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-rw-r--r--fs/io_uring.c11164
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diff --git a/fs/io_uring.c b/fs/io_uring.c
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index fb2a0cb4aaf8..000000000000
--- a/fs/io_uring.c
+++ /dev/null
@@ -1,11164 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0
-/*
- * Shared application/kernel submission and completion ring pairs, for
- * supporting fast/efficient IO.
- *
- * A note on the read/write ordering memory barriers that are matched between
- * the application and kernel side.
- *
- * After the application reads the CQ ring tail, it must use an
- * appropriate smp_rmb() to pair with the smp_wmb() the kernel uses
- * before writing the tail (using smp_load_acquire to read the tail will
- * do). It also needs a smp_mb() before updating CQ head (ordering the
- * entry load(s) with the head store), pairing with an implicit barrier
- * through a control-dependency in io_get_cqe (smp_store_release to
- * store head will do). Failure to do so could lead to reading invalid
- * CQ entries.
- *
- * Likewise, the application must use an appropriate smp_wmb() before
- * writing the SQ tail (ordering SQ entry stores with the tail store),
- * which pairs with smp_load_acquire in io_get_sqring (smp_store_release
- * to store the tail will do). And it needs a barrier ordering the SQ
- * head load before writing new SQ entries (smp_load_acquire to read
- * head will do).
- *
- * When using the SQ poll thread (IORING_SETUP_SQPOLL), the application
- * needs to check the SQ flags for IORING_SQ_NEED_WAKEUP *after*
- * updating the SQ tail; a full memory barrier smp_mb() is needed
- * between.
- *
- * Also see the examples in the liburing library:
- *
- * git://git.kernel.dk/liburing
- *
- * io_uring also uses READ/WRITE_ONCE() for _any_ store or load that happens
- * from data shared between the kernel and application. This is done both
- * for ordering purposes, but also to ensure that once a value is loaded from
- * data that the application could potentially modify, it remains stable.
- *
- * Copyright (C) 2018-2019 Jens Axboe
- * Copyright (c) 2018-2019 Christoph Hellwig
- */
-#include <linux/kernel.h>
-#include <linux/init.h>
-#include <linux/errno.h>
-#include <linux/syscalls.h>
-#include <linux/compat.h>
-#include <net/compat.h>
-#include <linux/refcount.h>
-#include <linux/uio.h>
-#include <linux/bits.h>
-
-#include <linux/sched/signal.h>
-#include <linux/fs.h>
-#include <linux/file.h>
-#include <linux/fdtable.h>
-#include <linux/mm.h>
-#include <linux/mman.h>
-#include <linux/percpu.h>
-#include <linux/slab.h>
-#include <linux/blkdev.h>
-#include <linux/bvec.h>
-#include <linux/net.h>
-#include <net/sock.h>
-#include <net/af_unix.h>
-#include <net/scm.h>
-#include <linux/anon_inodes.h>
-#include <linux/sched/mm.h>
-#include <linux/uaccess.h>
-#include <linux/nospec.h>
-#include <linux/sizes.h>
-#include <linux/hugetlb.h>
-#include <linux/highmem.h>
-#include <linux/namei.h>
-#include <linux/fsnotify.h>
-#include <linux/fadvise.h>
-#include <linux/eventpoll.h>
-#include <linux/splice.h>
-#include <linux/task_work.h>
-#include <linux/pagemap.h>
-#include <linux/io_uring.h>
-#include <linux/tracehook.h>
-#include <linux/audit.h>
-#include <linux/security.h>
-
-#define CREATE_TRACE_POINTS
-#include <trace/events/io_uring.h>
-
-#include <uapi/linux/io_uring.h>
-
-#include "internal.h"
-#include "io-wq.h"
-
-#define IORING_MAX_ENTRIES 32768
-#define IORING_MAX_CQ_ENTRIES (2 * IORING_MAX_ENTRIES)
-#define IORING_SQPOLL_CAP_ENTRIES_VALUE 8
-
-/* only define max */
-#define IORING_MAX_FIXED_FILES (1U << 15)
-#define IORING_MAX_RESTRICTIONS (IORING_RESTRICTION_LAST + \
- IORING_REGISTER_LAST + IORING_OP_LAST)
-
-#define IO_RSRC_TAG_TABLE_SHIFT (PAGE_SHIFT - 3)
-#define IO_RSRC_TAG_TABLE_MAX (1U << IO_RSRC_TAG_TABLE_SHIFT)
-#define IO_RSRC_TAG_TABLE_MASK (IO_RSRC_TAG_TABLE_MAX - 1)
-
-#define IORING_MAX_REG_BUFFERS (1U << 14)
-
-#define SQE_COMMON_FLAGS (IOSQE_FIXED_FILE | IOSQE_IO_LINK | \
- IOSQE_IO_HARDLINK | IOSQE_ASYNC)
-
-#define SQE_VALID_FLAGS (SQE_COMMON_FLAGS|IOSQE_BUFFER_SELECT|IOSQE_IO_DRAIN)
-
-#define IO_REQ_CLEAN_FLAGS (REQ_F_BUFFER_SELECTED | REQ_F_NEED_CLEANUP | \
- REQ_F_POLLED | REQ_F_INFLIGHT | REQ_F_CREDS | \
- REQ_F_ASYNC_DATA)
-
-#define IO_TCTX_REFS_CACHE_NR (1U << 10)
-
-struct io_uring {
- u32 head ____cacheline_aligned_in_smp;
- u32 tail ____cacheline_aligned_in_smp;
-};
-
-/*
- * This data is shared with the application through the mmap at offsets
- * IORING_OFF_SQ_RING and IORING_OFF_CQ_RING.
- *
- * The offsets to the member fields are published through struct
- * io_sqring_offsets when calling io_uring_setup.
- */
-struct io_rings {
- /*
- * Head and tail offsets into the ring; the offsets need to be
- * masked to get valid indices.
- *
- * The kernel controls head of the sq ring and the tail of the cq ring,
- * and the application controls tail of the sq ring and the head of the
- * cq ring.
- */
- struct io_uring sq, cq;
- /*
- * Bitmasks to apply to head and tail offsets (constant, equals
- * ring_entries - 1)
- */
- u32 sq_ring_mask, cq_ring_mask;
- /* Ring sizes (constant, power of 2) */
- u32 sq_ring_entries, cq_ring_entries;
- /*
- * Number of invalid entries dropped by the kernel due to
- * invalid index stored in array
- *
- * Written by the kernel, shouldn't be modified by the
- * application (i.e. get number of "new events" by comparing to
- * cached value).
- *
- * After a new SQ head value was read by the application this
- * counter includes all submissions that were dropped reaching
- * the new SQ head (and possibly more).
- */
- u32 sq_dropped;
- /*
- * Runtime SQ flags
- *
- * Written by the kernel, shouldn't be modified by the
- * application.
- *
- * The application needs a full memory barrier before checking
- * for IORING_SQ_NEED_WAKEUP after updating the sq tail.
- */
- u32 sq_flags;
- /*
- * Runtime CQ flags
- *
- * Written by the application, shouldn't be modified by the
- * kernel.
- */
- u32 cq_flags;
- /*
- * Number of completion events lost because the queue was full;
- * this should be avoided by the application by making sure
- * there are not more requests pending than there is space in
- * the completion queue.
- *
- * Written by the kernel, shouldn't be modified by the
- * application (i.e. get number of "new events" by comparing to
- * cached value).
- *
- * As completion events come in out of order this counter is not
- * ordered with any other data.
- */
- u32 cq_overflow;
- /*
- * Ring buffer of completion events.
- *
- * The kernel writes completion events fresh every time they are
- * produced, so the application is allowed to modify pending
- * entries.
- */
- struct io_uring_cqe cqes[] ____cacheline_aligned_in_smp;
-};
-
-enum io_uring_cmd_flags {
- IO_URING_F_COMPLETE_DEFER = 1,
- IO_URING_F_UNLOCKED = 2,
- /* int's last bit, sign checks are usually faster than a bit test */
- IO_URING_F_NONBLOCK = INT_MIN,
-};
-
-struct io_mapped_ubuf {
- u64 ubuf;
- u64 ubuf_end;
- unsigned int nr_bvecs;
- unsigned long acct_pages;
- struct bio_vec bvec[];
-};
-
-struct io_ring_ctx;
-
-struct io_overflow_cqe {
- struct io_uring_cqe cqe;
- struct list_head list;
-};
-
-struct io_fixed_file {
- /* file * with additional FFS_* flags */
- unsigned long file_ptr;
-};
-
-struct io_rsrc_put {
- struct list_head list;
- u64 tag;
- union {
- void *rsrc;
- struct file *file;
- struct io_mapped_ubuf *buf;
- };
-};
-
-struct io_file_table {
- struct io_fixed_file *files;
-};
-
-struct io_rsrc_node {
- struct percpu_ref refs;
- struct list_head node;
- struct list_head rsrc_list;
- struct io_rsrc_data *rsrc_data;
- struct llist_node llist;
- bool done;
-};
-
-typedef void (rsrc_put_fn)(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc);
-
-struct io_rsrc_data {
- struct io_ring_ctx *ctx;
-
- u64 **tags;
- unsigned int nr;
- rsrc_put_fn *do_put;
- atomic_t refs;
- struct completion done;
- bool quiesce;
-};
-
-struct io_buffer {
- struct list_head list;
- __u64 addr;
- __u32 len;
- __u16 bid;
-};
-
-struct io_restriction {
- DECLARE_BITMAP(register_op, IORING_REGISTER_LAST);
- DECLARE_BITMAP(sqe_op, IORING_OP_LAST);
- u8 sqe_flags_allowed;
- u8 sqe_flags_required;
- bool registered;
-};
-
-enum {
- IO_SQ_THREAD_SHOULD_STOP = 0,
- IO_SQ_THREAD_SHOULD_PARK,
-};
-
-struct io_sq_data {
- refcount_t refs;
- atomic_t park_pending;
- struct mutex lock;
-
- /* ctx's that are using this sqd */
- struct list_head ctx_list;
-
- struct task_struct *thread;
- struct wait_queue_head wait;
-
- unsigned sq_thread_idle;
- int sq_cpu;
- pid_t task_pid;
- pid_t task_tgid;
-
- unsigned long state;
- struct completion exited;
-};
-
-#define IO_COMPL_BATCH 32
-#define IO_REQ_CACHE_SIZE 32
-#define IO_REQ_ALLOC_BATCH 8
-
-struct io_submit_link {
- struct io_kiocb *head;
- struct io_kiocb *last;
-};
-
-struct io_submit_state {
- /* inline/task_work completion list, under ->uring_lock */
- struct io_wq_work_node free_list;
- /* batch completion logic */
- struct io_wq_work_list compl_reqs;
- struct io_submit_link link;
-
- bool plug_started;
- bool need_plug;
- unsigned short submit_nr;
- struct blk_plug plug;
-};
-
-struct io_ring_ctx {
- /* const or read-mostly hot data */
- struct {
- struct percpu_ref refs;
-
- struct io_rings *rings;
- unsigned int flags;
- unsigned int compat: 1;
- unsigned int drain_next: 1;
- unsigned int eventfd_async: 1;
- unsigned int restricted: 1;
- unsigned int off_timeout_used: 1;
- unsigned int drain_active: 1;
- } ____cacheline_aligned_in_smp;
-
- /* submission data */
- struct {
- struct mutex uring_lock;
-
- /*
- * Ring buffer of indices into array of io_uring_sqe, which is
- * mmapped by the application using the IORING_OFF_SQES offset.
- *
- * This indirection could e.g. be used to assign fixed
- * io_uring_sqe entries to operations and only submit them to
- * the queue when needed.
- *
- * The kernel modifies neither the indices array nor the entries
- * array.
- */
- u32 *sq_array;
- struct io_uring_sqe *sq_sqes;
- unsigned cached_sq_head;
- unsigned sq_entries;
- struct list_head defer_list;
-
- /*
- * Fixed resources fast path, should be accessed only under
- * uring_lock, and updated through io_uring_register(2)
- */
- struct io_rsrc_node *rsrc_node;
- int rsrc_cached_refs;
- struct io_file_table file_table;
- unsigned nr_user_files;
- unsigned nr_user_bufs;
- struct io_mapped_ubuf **user_bufs;
-
- struct io_submit_state submit_state;
- struct list_head timeout_list;
- struct list_head ltimeout_list;
- struct list_head cq_overflow_list;
- struct xarray io_buffers;
- struct xarray personalities;
- u32 pers_next;
- unsigned sq_thread_idle;
- } ____cacheline_aligned_in_smp;
-
- /* IRQ completion list, under ->completion_lock */
- struct io_wq_work_list locked_free_list;
- unsigned int locked_free_nr;
-
- const struct cred *sq_creds; /* cred used for __io_sq_thread() */
- struct io_sq_data *sq_data; /* if using sq thread polling */
-
- struct wait_queue_head sqo_sq_wait;
- struct list_head sqd_list;
-
- unsigned long check_cq_overflow;
-
- struct {
- unsigned cached_cq_tail;
- unsigned cq_entries;
- struct eventfd_ctx *cq_ev_fd;
- struct wait_queue_head cq_wait;
- unsigned cq_extra;
- atomic_t cq_timeouts;
- unsigned cq_last_tm_flush;
- } ____cacheline_aligned_in_smp;
-
- struct {
- spinlock_t completion_lock;
-
- spinlock_t timeout_lock;
-
- /*
- * ->iopoll_list is protected by the ctx->uring_lock for
- * io_uring instances that don't use IORING_SETUP_SQPOLL.
- * For SQPOLL, only the single threaded io_sq_thread() will
- * manipulate the list, hence no extra locking is needed there.
- */
- struct io_wq_work_list iopoll_list;
- struct hlist_head *cancel_hash;
- unsigned cancel_hash_bits;
- bool poll_multi_queue;
- } ____cacheline_aligned_in_smp;
-
- struct io_restriction restrictions;
-
- /* slow path rsrc auxilary data, used by update/register */
- struct {
- struct io_rsrc_node *rsrc_backup_node;
- struct io_mapped_ubuf *dummy_ubuf;
- struct io_rsrc_data *file_data;
- struct io_rsrc_data *buf_data;
-
- struct delayed_work rsrc_put_work;
- struct llist_head rsrc_put_llist;
- struct list_head rsrc_ref_list;
- spinlock_t rsrc_ref_lock;
- };
-
- /* Keep this last, we don't need it for the fast path */
- struct {
- #if defined(CONFIG_UNIX)
- struct socket *ring_sock;
- #endif
- /* hashed buffered write serialization */
- struct io_wq_hash *hash_map;
-
- /* Only used for accounting purposes */
- struct user_struct *user;
- struct mm_struct *mm_account;
-
- /* ctx exit and cancelation */
- struct llist_head fallback_llist;
- struct delayed_work fallback_work;
- struct work_struct exit_work;
- struct list_head tctx_list;
- struct completion ref_comp;
- u32 iowq_limits[2];
- bool iowq_limits_set;
- };
-};
-
-struct io_uring_task {
- /* submission side */
- int cached_refs;
- struct xarray xa;
- struct wait_queue_head wait;
- const struct io_ring_ctx *last;
- struct io_wq *io_wq;
- struct percpu_counter inflight;
- atomic_t inflight_tracked;
- atomic_t in_idle;
-
- spinlock_t task_lock;
- struct io_wq_work_list task_list;
- struct callback_head task_work;
- bool task_running;
-};
-
-/*
- * First field must be the file pointer in all the
- * iocb unions! See also 'struct kiocb' in <linux/fs.h>
- */
-struct io_poll_iocb {
- struct file *file;
- struct wait_queue_head *head;
- __poll_t events;
- bool done;
- bool canceled;
- struct wait_queue_entry wait;
-};
-
-struct io_poll_update {
- struct file *file;
- u64 old_user_data;
- u64 new_user_data;
- __poll_t events;
- bool update_events;
- bool update_user_data;
-};
-
-struct io_close {
- struct file *file;
- int fd;
- u32 file_slot;
-};
-
-struct io_timeout_data {
- struct io_kiocb *req;
- struct hrtimer timer;
- struct timespec64 ts;
- enum hrtimer_mode mode;
- u32 flags;
-};
-
-struct io_accept {
- struct file *file;
- struct sockaddr __user *addr;
- int __user *addr_len;
- int flags;
- u32 file_slot;
- unsigned long nofile;
-};
-
-struct io_sync {
- struct file *file;
- loff_t len;
- loff_t off;
- int flags;
- int mode;
-};
-
-struct io_cancel {
- struct file *file;
- u64 addr;
-};
-
-struct io_timeout {
- struct file *file;
- u32 off;
- u32 target_seq;
- struct list_head list;
- /* head of the link, used by linked timeouts only */
- struct io_kiocb *head;
- /* for linked completions */
- struct io_kiocb *prev;
-};
-
-struct io_timeout_rem {
- struct file *file;
- u64 addr;
-
- /* timeout update */
- struct timespec64 ts;
- u32 flags;
- bool ltimeout;
-};
-
-struct io_rw {
- /* NOTE: kiocb has the file as the first member, so don't do it here */
- struct kiocb kiocb;
- u64 addr;
- u64 len;
-};
-
-struct io_connect {
- struct file *file;
- struct sockaddr __user *addr;
- int addr_len;
-};
-
-struct io_sr_msg {
- struct file *file;
- union {
- struct compat_msghdr __user *umsg_compat;
- struct user_msghdr __user *umsg;
- void __user *buf;
- };
- int msg_flags;
- int bgid;
- size_t len;
-};
-
-struct io_open {
- struct file *file;
- int dfd;
- u32 file_slot;
- struct filename *filename;
- struct open_how how;
- unsigned long nofile;
-};
-
-struct io_rsrc_update {
- struct file *file;
- u64 arg;
- u32 nr_args;
- u32 offset;
-};
-
-struct io_fadvise {
- struct file *file;
- u64 offset;
- u32 len;
- u32 advice;
-};
-
-struct io_madvise {
- struct file *file;
- u64 addr;
- u32 len;
- u32 advice;
-};
-
-struct io_epoll {
- struct file *file;
- int epfd;
- int op;
- int fd;
- struct epoll_event event;
-};
-
-struct io_splice {
- struct file *file_out;
- struct file *file_in;
- loff_t off_out;
- loff_t off_in;
- u64 len;
- unsigned int flags;
-};
-
-struct io_provide_buf {
- struct file *file;
- __u64 addr;
- __u32 len;
- __u32 bgid;
- __u16 nbufs;
- __u16 bid;
-};
-
-struct io_statx {
- struct file *file;
- int dfd;
- unsigned int mask;
- unsigned int flags;
- const char __user *filename;
- struct statx __user *buffer;
-};
-
-struct io_shutdown {
- struct file *file;
- int how;
-};
-
-struct io_rename {
- struct file *file;
- int old_dfd;
- int new_dfd;
- struct filename *oldpath;
- struct filename *newpath;
- int flags;
-};
-
-struct io_unlink {
- struct file *file;
- int dfd;
- int flags;
- struct filename *filename;
-};
-
-struct io_mkdir {
- struct file *file;
- int dfd;
- umode_t mode;
- struct filename *filename;
-};
-
-struct io_symlink {
- struct file *file;
- int new_dfd;
- struct filename *oldpath;
- struct filename *newpath;
-};
-
-struct io_hardlink {
- struct file *file;
- int old_dfd;
- int new_dfd;
- struct filename *oldpath;
- struct filename *newpath;
- int flags;
-};
-
-struct io_async_connect {
- struct sockaddr_storage address;
-};
-
-struct io_async_msghdr {
- struct iovec fast_iov[UIO_FASTIOV];
- /* points to an allocated iov, if NULL we use fast_iov instead */
- struct iovec *free_iov;
- struct sockaddr __user *uaddr;
- struct msghdr msg;
- struct sockaddr_storage addr;
-};
-
-struct io_rw_state {
- struct iov_iter iter;
- struct iov_iter_state iter_state;
- struct iovec fast_iov[UIO_FASTIOV];
-};
-
-struct io_async_rw {
- struct io_rw_state s;
- const struct iovec *free_iovec;
- size_t bytes_done;
- struct wait_page_queue wpq;
-};
-
-enum {
- REQ_F_FIXED_FILE_BIT = IOSQE_FIXED_FILE_BIT,
- REQ_F_IO_DRAIN_BIT = IOSQE_IO_DRAIN_BIT,
- REQ_F_LINK_BIT = IOSQE_IO_LINK_BIT,
- REQ_F_HARDLINK_BIT = IOSQE_IO_HARDLINK_BIT,
- REQ_F_FORCE_ASYNC_BIT = IOSQE_ASYNC_BIT,
- REQ_F_BUFFER_SELECT_BIT = IOSQE_BUFFER_SELECT_BIT,
-
- /* first byte is taken by user flags, shift it to not overlap */
- REQ_F_FAIL_BIT = 8,
- REQ_F_INFLIGHT_BIT,
- REQ_F_CUR_POS_BIT,
- REQ_F_NOWAIT_BIT,
- REQ_F_LINK_TIMEOUT_BIT,
- REQ_F_NEED_CLEANUP_BIT,
- REQ_F_POLLED_BIT,
- REQ_F_BUFFER_SELECTED_BIT,
- REQ_F_COMPLETE_INLINE_BIT,
- REQ_F_REISSUE_BIT,
- REQ_F_CREDS_BIT,
- REQ_F_REFCOUNT_BIT,
- REQ_F_ARM_LTIMEOUT_BIT,
- REQ_F_ASYNC_DATA_BIT,
- /* keep async read/write and isreg together and in order */
- REQ_F_SUPPORT_NOWAIT_BIT,
- REQ_F_ISREG_BIT,
-
- /* not a real bit, just to check we're not overflowing the space */
- __REQ_F_LAST_BIT,
-};
-
-enum {
- /* ctx owns file */
- REQ_F_FIXED_FILE = BIT(REQ_F_FIXED_FILE_BIT),
- /* drain existing IO first */
- REQ_F_IO_DRAIN = BIT(REQ_F_IO_DRAIN_BIT),
- /* linked sqes */
- REQ_F_LINK = BIT(REQ_F_LINK_BIT),
- /* doesn't sever on completion < 0 */
- REQ_F_HARDLINK = BIT(REQ_F_HARDLINK_BIT),
- /* IOSQE_ASYNC */
- REQ_F_FORCE_ASYNC = BIT(REQ_F_FORCE_ASYNC_BIT),
- /* IOSQE_BUFFER_SELECT */
- REQ_F_BUFFER_SELECT = BIT(REQ_F_BUFFER_SELECT_BIT),
-
- /* fail rest of links */
- REQ_F_FAIL = BIT(REQ_F_FAIL_BIT),
- /* on inflight list, should be cancelled and waited on exit reliably */
- REQ_F_INFLIGHT = BIT(REQ_F_INFLIGHT_BIT),
- /* read/write uses file position */
- REQ_F_CUR_POS = BIT(REQ_F_CUR_POS_BIT),
- /* must not punt to workers */
- REQ_F_NOWAIT = BIT(REQ_F_NOWAIT_BIT),
- /* has or had linked timeout */
- REQ_F_LINK_TIMEOUT = BIT(REQ_F_LINK_TIMEOUT_BIT),
- /* needs cleanup */
- REQ_F_NEED_CLEANUP = BIT(REQ_F_NEED_CLEANUP_BIT),
- /* already went through poll handler */
- REQ_F_POLLED = BIT(REQ_F_POLLED_BIT),
- /* buffer already selected */
- REQ_F_BUFFER_SELECTED = BIT(REQ_F_BUFFER_SELECTED_BIT),
- /* completion is deferred through io_comp_state */
- REQ_F_COMPLETE_INLINE = BIT(REQ_F_COMPLETE_INLINE_BIT),
- /* caller should reissue async */
- REQ_F_REISSUE = BIT(REQ_F_REISSUE_BIT),
- /* supports async reads/writes */
- REQ_F_SUPPORT_NOWAIT = BIT(REQ_F_SUPPORT_NOWAIT_BIT),
- /* regular file */
- REQ_F_ISREG = BIT(REQ_F_ISREG_BIT),
- /* has creds assigned */
- REQ_F_CREDS = BIT(REQ_F_CREDS_BIT),
- /* skip refcounting if not set */
- REQ_F_REFCOUNT = BIT(REQ_F_REFCOUNT_BIT),
- /* there is a linked timeout that has to be armed */
- REQ_F_ARM_LTIMEOUT = BIT(REQ_F_ARM_LTIMEOUT_BIT),
- /* ->async_data allocated */
- REQ_F_ASYNC_DATA = BIT(REQ_F_ASYNC_DATA_BIT),
-};
-
-struct async_poll {
- struct io_poll_iocb poll;
- struct io_poll_iocb *double_poll;
-};
-
-typedef void (*io_req_tw_func_t)(struct io_kiocb *req, bool *locked);
-
-struct io_task_work {
- union {
- struct io_wq_work_node node;
- struct llist_node fallback_node;
- };
- io_req_tw_func_t func;
-};
-
-enum {
- IORING_RSRC_FILE = 0,
- IORING_RSRC_BUFFER = 1,
-};
-
-/*
- * NOTE! Each of the iocb union members has the file pointer
- * as the first entry in their struct definition. So you can
- * access the file pointer through any of the sub-structs,
- * or directly as just 'ki_filp' in this struct.
- */
-struct io_kiocb {
- union {
- struct file *file;
- struct io_rw rw;
- struct io_poll_iocb poll;
- struct io_poll_update poll_update;
- struct io_accept accept;
- struct io_sync sync;
- struct io_cancel cancel;
- struct io_timeout timeout;
- struct io_timeout_rem timeout_rem;
- struct io_connect connect;
- struct io_sr_msg sr_msg;
- struct io_open open;
- struct io_close close;
- struct io_rsrc_update rsrc_update;
- struct io_fadvise fadvise;
- struct io_madvise madvise;
- struct io_epoll epoll;
- struct io_splice splice;
- struct io_provide_buf pbuf;
- struct io_statx statx;
- struct io_shutdown shutdown;
- struct io_rename rename;
- struct io_unlink unlink;
- struct io_mkdir mkdir;
- struct io_symlink symlink;
- struct io_hardlink hardlink;
- };
-
- u8 opcode;
- /* polled IO has completed */
- u8 iopoll_completed;
- u16 buf_index;
- unsigned int flags;
-
- u64 user_data;
- u32 result;
- u32 cflags;
-
- struct io_ring_ctx *ctx;
- struct task_struct *task;
-
- struct percpu_ref *fixed_rsrc_refs;
- /* store used ubuf, so we can prevent reloading */
- struct io_mapped_ubuf *imu;
-
- /* used by request caches, completion batching and iopoll */
- struct io_wq_work_node comp_list;
- atomic_t refs;
- struct io_kiocb *link;
- struct io_task_work io_task_work;
- /* for polled requests, i.e. IORING_OP_POLL_ADD and async armed poll */
- struct hlist_node hash_node;
- /* internal polling, see IORING_FEAT_FAST_POLL */
- struct async_poll *apoll;
- /* opcode allocated if it needs to store data for async defer */
- void *async_data;
- struct io_wq_work work;
- /* custom credentials, valid IFF REQ_F_CREDS is set */
- const struct cred *creds;
- /* stores selected buf, valid IFF REQ_F_BUFFER_SELECTED is set */
- struct io_buffer *kbuf;
-};
-
-struct io_tctx_node {
- struct list_head ctx_node;
- struct task_struct *task;
- struct io_ring_ctx *ctx;
-};
-
-struct io_defer_entry {
- struct list_head list;
- struct io_kiocb *req;
- u32 seq;
-};
-
-struct io_op_def {
- /* needs req->file assigned */
- unsigned needs_file : 1;
- /* should block plug */
- unsigned plug : 1;
- /* hash wq insertion if file is a regular file */
- unsigned hash_reg_file : 1;
- /* unbound wq insertion if file is a non-regular file */
- unsigned unbound_nonreg_file : 1;
- /* set if opcode supports polled "wait" */
- unsigned pollin : 1;
- unsigned pollout : 1;
- /* op supports buffer selection */
- unsigned buffer_select : 1;
- /* do prep async if is going to be punted */
- unsigned needs_async_setup : 1;
- /* opcode is not supported by this kernel */
- unsigned not_supported : 1;
- /* skip auditing */
- unsigned audit_skip : 1;
- /* size of async data needed, if any */
- unsigned short async_size;
-};
-
-static const struct io_op_def io_op_defs[] = {
- [IORING_OP_NOP] = {},
- [IORING_OP_READV] = {
- .needs_file = 1,
- .unbound_nonreg_file = 1,
- .pollin = 1,
- .buffer_select = 1,
- .needs_async_setup = 1,
- .plug = 1,
- .audit_skip = 1,
- .async_size = sizeof(struct io_async_rw),
- },
- [IORING_OP_WRITEV] = {
- .needs_file = 1,
- .hash_reg_file = 1,
- .unbound_nonreg_file = 1,
- .pollout = 1,
- .needs_async_setup = 1,
- .plug = 1,
- .audit_skip = 1,
- .async_size = sizeof(struct io_async_rw),
- },
- [IORING_OP_FSYNC] = {
- .needs_file = 1,
- .audit_skip = 1,
- },
- [IORING_OP_READ_FIXED] = {
- .needs_file = 1,
- .unbound_nonreg_file = 1,
- .pollin = 1,
- .plug = 1,
- .audit_skip = 1,
- .async_size = sizeof(struct io_async_rw),
- },
- [IORING_OP_WRITE_FIXED] = {
- .needs_file = 1,
- .hash_reg_file = 1,
- .unbound_nonreg_file = 1,
- .pollout = 1,
- .plug = 1,
- .audit_skip = 1,
- .async_size = sizeof(struct io_async_rw),
- },
- [IORING_OP_POLL_ADD] = {
- .needs_file = 1,
- .unbound_nonreg_file = 1,
- .audit_skip = 1,
- },
- [IORING_OP_POLL_REMOVE] = {
- .audit_skip = 1,
- },
- [IORING_OP_SYNC_FILE_RANGE] = {
- .needs_file = 1,
- .audit_skip = 1,
- },
- [IORING_OP_SENDMSG] = {
- .needs_file = 1,
- .unbound_nonreg_file = 1,
- .pollout = 1,
- .needs_async_setup = 1,
- .async_size = sizeof(struct io_async_msghdr),
- },
- [IORING_OP_RECVMSG] = {
- .needs_file = 1,
- .unbound_nonreg_file = 1,
- .pollin = 1,
- .buffer_select = 1,
- .needs_async_setup = 1,
- .async_size = sizeof(struct io_async_msghdr),
- },
- [IORING_OP_TIMEOUT] = {
- .audit_skip = 1,
- .async_size = sizeof(struct io_timeout_data),
- },
- [IORING_OP_TIMEOUT_REMOVE] = {
- /* used by timeout updates' prep() */
- .audit_skip = 1,
- },
- [IORING_OP_ACCEPT] = {
- .needs_file = 1,
- .unbound_nonreg_file = 1,
- .pollin = 1,
- },
- [IORING_OP_ASYNC_CANCEL] = {
- .audit_skip = 1,
- },
- [IORING_OP_LINK_TIMEOUT] = {
- .audit_skip = 1,
- .async_size = sizeof(struct io_timeout_data),
- },
- [IORING_OP_CONNECT] = {
- .needs_file = 1,
- .unbound_nonreg_file = 1,
- .pollout = 1,
- .needs_async_setup = 1,
- .async_size = sizeof(struct io_async_connect),
- },
- [IORING_OP_FALLOCATE] = {
- .needs_file = 1,
- },
- [IORING_OP_OPENAT] = {},
- [IORING_OP_CLOSE] = {},
- [IORING_OP_FILES_UPDATE] = {
- .audit_skip = 1,
- },
- [IORING_OP_STATX] = {
- .audit_skip = 1,
- },
- [IORING_OP_READ] = {
- .needs_file = 1,
- .unbound_nonreg_file = 1,
- .pollin = 1,
- .buffer_select = 1,
- .plug = 1,
- .audit_skip = 1,
- .async_size = sizeof(struct io_async_rw),
- },
- [IORING_OP_WRITE] = {
- .needs_file = 1,
- .hash_reg_file = 1,
- .unbound_nonreg_file = 1,
- .pollout = 1,
- .plug = 1,
- .audit_skip = 1,
- .async_size = sizeof(struct io_async_rw),
- },
- [IORING_OP_FADVISE] = {
- .needs_file = 1,
- .audit_skip = 1,
- },
- [IORING_OP_MADVISE] = {},
- [IORING_OP_SEND] = {
- .needs_file = 1,
- .unbound_nonreg_file = 1,
- .pollout = 1,
- .audit_skip = 1,
- },
- [IORING_OP_RECV] = {
- .needs_file = 1,
- .unbound_nonreg_file = 1,
- .pollin = 1,
- .buffer_select = 1,
- .audit_skip = 1,
- },
- [IORING_OP_OPENAT2] = {
- },
- [IORING_OP_EPOLL_CTL] = {
- .unbound_nonreg_file = 1,
- .audit_skip = 1,
- },
- [IORING_OP_SPLICE] = {
- .needs_file = 1,
- .hash_reg_file = 1,
- .unbound_nonreg_file = 1,
- .audit_skip = 1,
- },
- [IORING_OP_PROVIDE_BUFFERS] = {
- .audit_skip = 1,
- },
- [IORING_OP_REMOVE_BUFFERS] = {
- .audit_skip = 1,
- },
- [IORING_OP_TEE] = {
- .needs_file = 1,
- .hash_reg_file = 1,
- .unbound_nonreg_file = 1,
- .audit_skip = 1,
- },
- [IORING_OP_SHUTDOWN] = {
- .needs_file = 1,
- },
- [IORING_OP_RENAMEAT] = {},
- [IORING_OP_UNLINKAT] = {},
- [IORING_OP_MKDIRAT] = {},
- [IORING_OP_SYMLINKAT] = {},
- [IORING_OP_LINKAT] = {},
-};
-
-/* requests with any of those set should undergo io_disarm_next() */
-#define IO_DISARM_MASK (REQ_F_ARM_LTIMEOUT | REQ_F_LINK_TIMEOUT | REQ_F_FAIL)
-
-static bool io_disarm_next(struct io_kiocb *req);
-static void io_uring_del_tctx_node(unsigned long index);
-static void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
- struct task_struct *task,
- bool cancel_all);
-static void io_uring_cancel_generic(bool cancel_all, struct io_sq_data *sqd);
-
-static bool io_cqring_fill_event(struct io_ring_ctx *ctx, u64 user_data,
- s32 res, u32 cflags);
-static void io_put_req(struct io_kiocb *req);
-static void io_put_req_deferred(struct io_kiocb *req);
-static void io_dismantle_req(struct io_kiocb *req);
-static void io_queue_linked_timeout(struct io_kiocb *req);
-static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
- struct io_uring_rsrc_update2 *up,
- unsigned nr_args);
-static void io_clean_op(struct io_kiocb *req);
-static struct file *io_file_get(struct io_ring_ctx *ctx,
- struct io_kiocb *req, int fd, bool fixed);
-static void __io_queue_sqe(struct io_kiocb *req);
-static void io_rsrc_put_work(struct work_struct *work);
-
-static void io_req_task_queue(struct io_kiocb *req);
-static void __io_submit_flush_completions(struct io_ring_ctx *ctx);
-static int io_req_prep_async(struct io_kiocb *req);
-
-static int io_install_fixed_file(struct io_kiocb *req, struct file *file,
- unsigned int issue_flags, u32 slot_index);
-static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags);
-
-static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer);
-
-static struct kmem_cache *req_cachep;
-
-static const struct file_operations io_uring_fops;
-
-struct sock *io_uring_get_socket(struct file *file)
-{
-#if defined(CONFIG_UNIX)
- if (file->f_op == &io_uring_fops) {
- struct io_ring_ctx *ctx = file->private_data;
-
- return ctx->ring_sock->sk;
- }
-#endif
- return NULL;
-}
-EXPORT_SYMBOL(io_uring_get_socket);
-
-static inline void io_tw_lock(struct io_ring_ctx *ctx, bool *locked)
-{
- if (!*locked) {
- mutex_lock(&ctx->uring_lock);
- *locked = true;
- }
-}
-
-#define io_for_each_link(pos, head) \
- for (pos = (head); pos; pos = pos->link)
-
-/*
- * Shamelessly stolen from the mm implementation of page reference checking,
- * see commit f958d7b528b1 for details.
- */
-#define req_ref_zero_or_close_to_overflow(req) \
- ((unsigned int) atomic_read(&(req->refs)) + 127u <= 127u)
-
-static inline bool req_ref_inc_not_zero(struct io_kiocb *req)
-{
- WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
- return atomic_inc_not_zero(&req->refs);
-}
-
-static inline bool req_ref_put_and_test(struct io_kiocb *req)
-{
- if (likely(!(req->flags & REQ_F_REFCOUNT)))
- return true;
-
- WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
- return atomic_dec_and_test(&req->refs);
-}
-
-static inline void req_ref_put(struct io_kiocb *req)
-{
- WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
- WARN_ON_ONCE(req_ref_put_and_test(req));
-}
-
-static inline void req_ref_get(struct io_kiocb *req)
-{
- WARN_ON_ONCE(!(req->flags & REQ_F_REFCOUNT));
- WARN_ON_ONCE(req_ref_zero_or_close_to_overflow(req));
- atomic_inc(&req->refs);
-}
-
-static inline void io_submit_flush_completions(struct io_ring_ctx *ctx)
-{
- if (!wq_list_empty(&ctx->submit_state.compl_reqs))
- __io_submit_flush_completions(ctx);
-}
-
-static inline void __io_req_set_refcount(struct io_kiocb *req, int nr)
-{
- if (!(req->flags & REQ_F_REFCOUNT)) {
- req->flags |= REQ_F_REFCOUNT;
- atomic_set(&req->refs, nr);
- }
-}
-
-static inline void io_req_set_refcount(struct io_kiocb *req)
-{
- __io_req_set_refcount(req, 1);
-}
-
-#define IO_RSRC_REF_BATCH 100
-
-static inline void io_req_put_rsrc_locked(struct io_kiocb *req,
- struct io_ring_ctx *ctx)
- __must_hold(&ctx->uring_lock)
-{
- struct percpu_ref *ref = req->fixed_rsrc_refs;
-
- if (ref) {
- if (ref == &ctx->rsrc_node->refs)
- ctx->rsrc_cached_refs++;
- else
- percpu_ref_put(ref);
- }
-}
-
-static inline void io_req_put_rsrc(struct io_kiocb *req, struct io_ring_ctx *ctx)
-{
- if (req->fixed_rsrc_refs)
- percpu_ref_put(req->fixed_rsrc_refs);
-}
-
-static __cold void io_rsrc_refs_drop(struct io_ring_ctx *ctx)
- __must_hold(&ctx->uring_lock)
-{
- if (ctx->rsrc_cached_refs) {
- percpu_ref_put_many(&ctx->rsrc_node->refs, ctx->rsrc_cached_refs);
- ctx->rsrc_cached_refs = 0;
- }
-}
-
-static void io_rsrc_refs_refill(struct io_ring_ctx *ctx)
- __must_hold(&ctx->uring_lock)
-{
- ctx->rsrc_cached_refs += IO_RSRC_REF_BATCH;
- percpu_ref_get_many(&ctx->rsrc_node->refs, IO_RSRC_REF_BATCH);
-}
-
-static inline void io_req_set_rsrc_node(struct io_kiocb *req,
- struct io_ring_ctx *ctx)
-{
- if (!req->fixed_rsrc_refs) {
- req->fixed_rsrc_refs = &ctx->rsrc_node->refs;
- ctx->rsrc_cached_refs--;
- if (unlikely(ctx->rsrc_cached_refs < 0))
- io_rsrc_refs_refill(ctx);
- }
-}
-
-static void io_refs_resurrect(struct percpu_ref *ref, struct completion *compl)
-{
- bool got = percpu_ref_tryget(ref);
-
- /* already at zero, wait for ->release() */
- if (!got)
- wait_for_completion(compl);
- percpu_ref_resurrect(ref);
- if (got)
- percpu_ref_put(ref);
-}
-
-static bool io_match_task(struct io_kiocb *head, struct task_struct *task,
- bool cancel_all)
- __must_hold(&req->ctx->timeout_lock)
-{
- struct io_kiocb *req;
-
- if (task && head->task != task)
- return false;
- if (cancel_all)
- return true;
-
- io_for_each_link(req, head) {
- if (req->flags & REQ_F_INFLIGHT)
- return true;
- }
- return false;
-}
-
-static bool io_match_linked(struct io_kiocb *head)
-{
- struct io_kiocb *req;
-
- io_for_each_link(req, head) {
- if (req->flags & REQ_F_INFLIGHT)
- return true;
- }
- return false;
-}
-
-/*
- * As io_match_task() but protected against racing with linked timeouts.
- * User must not hold timeout_lock.
- */
-static bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task,
- bool cancel_all)
-{
- bool matched;
-
- if (task && head->task != task)
- return false;
- if (cancel_all)
- return true;
-
- if (head->flags & REQ_F_LINK_TIMEOUT) {
- struct io_ring_ctx *ctx = head->ctx;
-
- /* protect against races with linked timeouts */
- spin_lock_irq(&ctx->timeout_lock);
- matched = io_match_linked(head);
- spin_unlock_irq(&ctx->timeout_lock);
- } else {
- matched = io_match_linked(head);
- }
- return matched;
-}
-
-static inline bool req_has_async_data(struct io_kiocb *req)
-{
- return req->flags & REQ_F_ASYNC_DATA;
-}
-
-static inline void req_set_fail(struct io_kiocb *req)
-{
- req->flags |= REQ_F_FAIL;
-}
-
-static inline void req_fail_link_node(struct io_kiocb *req, int res)
-{
- req_set_fail(req);
- req->result = res;
-}
-
-static __cold void io_ring_ctx_ref_free(struct percpu_ref *ref)
-{
- struct io_ring_ctx *ctx = container_of(ref, struct io_ring_ctx, refs);
-
- complete(&ctx->ref_comp);
-}
-
-static inline bool io_is_timeout_noseq(struct io_kiocb *req)
-{
- return !req->timeout.off;
-}
-
-static __cold void io_fallback_req_func(struct work_struct *work)
-{
- struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx,
- fallback_work.work);
- struct llist_node *node = llist_del_all(&ctx->fallback_llist);
- struct io_kiocb *req, *tmp;
- bool locked = false;
-
- percpu_ref_get(&ctx->refs);
- llist_for_each_entry_safe(req, tmp, node, io_task_work.fallback_node)
- req->io_task_work.func(req, &locked);
-
- if (locked) {
- io_submit_flush_completions(ctx);
- mutex_unlock(&ctx->uring_lock);
- }
- percpu_ref_put(&ctx->refs);
-}
-
-static __cold struct io_ring_ctx *io_ring_ctx_alloc(struct io_uring_params *p)
-{
- struct io_ring_ctx *ctx;
- int hash_bits;
-
- ctx = kzalloc(sizeof(*ctx), GFP_KERNEL);
- if (!ctx)
- return NULL;
-
- /*
- * Use 5 bits less than the max cq entries, that should give us around
- * 32 entries per hash list if totally full and uniformly spread.
- */
- hash_bits = ilog2(p->cq_entries);
- hash_bits -= 5;
- if (hash_bits <= 0)
- hash_bits = 1;
- ctx->cancel_hash_bits = hash_bits;
- ctx->cancel_hash = kmalloc((1U << hash_bits) * sizeof(struct hlist_head),
- GFP_KERNEL);
- if (!ctx->cancel_hash)
- goto err;
- __hash_init(ctx->cancel_hash, 1U << hash_bits);
-
- ctx->dummy_ubuf = kzalloc(sizeof(*ctx->dummy_ubuf), GFP_KERNEL);
- if (!ctx->dummy_ubuf)
- goto err;
- /* set invalid range, so io_import_fixed() fails meeting it */
- ctx->dummy_ubuf->ubuf = -1UL;
-
- if (percpu_ref_init(&ctx->refs, io_ring_ctx_ref_free,
- PERCPU_REF_ALLOW_REINIT, GFP_KERNEL))
- goto err;
-
- ctx->flags = p->flags;
- init_waitqueue_head(&ctx->sqo_sq_wait);
- INIT_LIST_HEAD(&ctx->sqd_list);
- INIT_LIST_HEAD(&ctx->cq_overflow_list);
- init_completion(&ctx->ref_comp);
- xa_init_flags(&ctx->io_buffers, XA_FLAGS_ALLOC1);
- xa_init_flags(&ctx->personalities, XA_FLAGS_ALLOC1);
- mutex_init(&ctx->uring_lock);
- init_waitqueue_head(&ctx->cq_wait);
- spin_lock_init(&ctx->completion_lock);
- spin_lock_init(&ctx->timeout_lock);
- INIT_WQ_LIST(&ctx->iopoll_list);
- INIT_LIST_HEAD(&ctx->defer_list);
- INIT_LIST_HEAD(&ctx->timeout_list);
- INIT_LIST_HEAD(&ctx->ltimeout_list);
- spin_lock_init(&ctx->rsrc_ref_lock);
- INIT_LIST_HEAD(&ctx->rsrc_ref_list);
- INIT_DELAYED_WORK(&ctx->rsrc_put_work, io_rsrc_put_work);
- init_llist_head(&ctx->rsrc_put_llist);
- INIT_LIST_HEAD(&ctx->tctx_list);
- ctx->submit_state.free_list.next = NULL;
- INIT_WQ_LIST(&ctx->locked_free_list);
- INIT_DELAYED_WORK(&ctx->fallback_work, io_fallback_req_func);
- INIT_WQ_LIST(&ctx->submit_state.compl_reqs);
- return ctx;
-err:
- kfree(ctx->dummy_ubuf);
- kfree(ctx->cancel_hash);
- kfree(ctx);
- return NULL;
-}
-
-static void io_account_cq_overflow(struct io_ring_ctx *ctx)
-{
- struct io_rings *r = ctx->rings;
-
- WRITE_ONCE(r->cq_overflow, READ_ONCE(r->cq_overflow) + 1);
- ctx->cq_extra--;
-}
-
-static bool req_need_defer(struct io_kiocb *req, u32 seq)
-{
- if (unlikely(req->flags & REQ_F_IO_DRAIN)) {
- struct io_ring_ctx *ctx = req->ctx;
-
- return seq + READ_ONCE(ctx->cq_extra) != ctx->cached_cq_tail;
- }
-
- return false;
-}
-
-#define FFS_NOWAIT 0x1UL
-#define FFS_ISREG 0x2UL
-#define FFS_MASK ~(FFS_NOWAIT|FFS_ISREG)
-
-static inline bool io_req_ffs_set(struct io_kiocb *req)
-{
- return req->flags & REQ_F_FIXED_FILE;
-}
-
-static inline void io_req_track_inflight(struct io_kiocb *req)
-{
- if (!(req->flags & REQ_F_INFLIGHT)) {
- req->flags |= REQ_F_INFLIGHT;
- atomic_inc(&current->io_uring->inflight_tracked);
- }
-}
-
-static struct io_kiocb *__io_prep_linked_timeout(struct io_kiocb *req)
-{
- if (WARN_ON_ONCE(!req->link))
- return NULL;
-
- req->flags &= ~REQ_F_ARM_LTIMEOUT;
- req->flags |= REQ_F_LINK_TIMEOUT;
-
- /* linked timeouts should have two refs once prep'ed */
- io_req_set_refcount(req);
- __io_req_set_refcount(req->link, 2);
- return req->link;
-}
-
-static inline struct io_kiocb *io_prep_linked_timeout(struct io_kiocb *req)
-{
- if (likely(!(req->flags & REQ_F_ARM_LTIMEOUT)))
- return NULL;
- return __io_prep_linked_timeout(req);
-}
-
-static void io_prep_async_work(struct io_kiocb *req)
-{
- const struct io_op_def *def = &io_op_defs[req->opcode];
- struct io_ring_ctx *ctx = req->ctx;
-
- if (!(req->flags & REQ_F_CREDS)) {
- req->flags |= REQ_F_CREDS;
- req->creds = get_current_cred();
- }
-
- req->work.list.next = NULL;
- req->work.flags = 0;
- if (req->flags & REQ_F_FORCE_ASYNC)
- req->work.flags |= IO_WQ_WORK_CONCURRENT;
-
- if (req->flags & REQ_F_ISREG) {
- if (def->hash_reg_file || (ctx->flags & IORING_SETUP_IOPOLL))
- io_wq_hash_work(&req->work, file_inode(req->file));
- } else if (!req->file || !S_ISBLK(file_inode(req->file)->i_mode)) {
- if (def->unbound_nonreg_file)
- req->work.flags |= IO_WQ_WORK_UNBOUND;
- }
-
- switch (req->opcode) {
- case IORING_OP_SPLICE:
- case IORING_OP_TEE:
- if (!S_ISREG(file_inode(req->splice.file_in)->i_mode))
- req->work.flags |= IO_WQ_WORK_UNBOUND;
- break;
- }
-}
-
-static void io_prep_async_link(struct io_kiocb *req)
-{
- struct io_kiocb *cur;
-
- if (req->flags & REQ_F_LINK_TIMEOUT) {
- struct io_ring_ctx *ctx = req->ctx;
-
- spin_lock_irq(&ctx->timeout_lock);
- io_for_each_link(cur, req)
- io_prep_async_work(cur);
- spin_unlock_irq(&ctx->timeout_lock);
- } else {
- io_for_each_link(cur, req)
- io_prep_async_work(cur);
- }
-}
-
-static inline void io_req_add_compl_list(struct io_kiocb *req)
-{
- struct io_submit_state *state = &req->ctx->submit_state;
-
- wq_list_add_tail(&req->comp_list, &state->compl_reqs);
-}
-
-static void io_queue_async_work(struct io_kiocb *req, bool *dont_use)
-{
- struct io_ring_ctx *ctx = req->ctx;
- struct io_kiocb *link = io_prep_linked_timeout(req);
- struct io_uring_task *tctx = req->task->io_uring;
-
- BUG_ON(!tctx);
- BUG_ON(!tctx->io_wq);
-
- /* init ->work of the whole link before punting */
- io_prep_async_link(req);
-
- /*
- * Not expected to happen, but if we do have a bug where this _can_
- * happen, catch it here and ensure the request is marked as
- * canceled. That will make io-wq go through the usual work cancel
- * procedure rather than attempt to run this request (or create a new
- * worker for it).
- */
- if (WARN_ON_ONCE(!same_thread_group(req->task, current)))
- req->work.flags |= IO_WQ_WORK_CANCEL;
-
- trace_io_uring_queue_async_work(ctx, io_wq_is_hashed(&req->work), req,
- &req->work, req->flags);
- io_wq_enqueue(tctx->io_wq, &req->work);
- if (link)
- io_queue_linked_timeout(link);
-}
-
-static void io_kill_timeout(struct io_kiocb *req, int status)
- __must_hold(&req->ctx->completion_lock)
- __must_hold(&req->ctx->timeout_lock)
-{
- struct io_timeout_data *io = req->async_data;
-
- if (hrtimer_try_to_cancel(&io->timer) != -1) {
- if (status)
- req_set_fail(req);
- atomic_set(&req->ctx->cq_timeouts,
- atomic_read(&req->ctx->cq_timeouts) + 1);
- list_del_init(&req->timeout.list);
- io_cqring_fill_event(req->ctx, req->user_data, status, 0);
- io_put_req_deferred(req);
- }
-}
-
-static __cold void io_queue_deferred(struct io_ring_ctx *ctx)
-{
- while (!list_empty(&ctx->defer_list)) {
- struct io_defer_entry *de = list_first_entry(&ctx->defer_list,
- struct io_defer_entry, list);
-
- if (req_need_defer(de->req, de->seq))
- break;
- list_del_init(&de->list);
- io_req_task_queue(de->req);
- kfree(de);
- }
-}
-
-static __cold void io_flush_timeouts(struct io_ring_ctx *ctx)
- __must_hold(&ctx->completion_lock)
-{
- u32 seq = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
-
- spin_lock_irq(&ctx->timeout_lock);
- while (!list_empty(&ctx->timeout_list)) {
- u32 events_needed, events_got;
- struct io_kiocb *req = list_first_entry(&ctx->timeout_list,
- struct io_kiocb, timeout.list);
-
- if (io_is_timeout_noseq(req))
- break;
-
- /*
- * Since seq can easily wrap around over time, subtract
- * the last seq at which timeouts were flushed before comparing.
- * Assuming not more than 2^31-1 events have happened since,
- * these subtractions won't have wrapped, so we can check if
- * target is in [last_seq, current_seq] by comparing the two.
- */
- events_needed = req->timeout.target_seq - ctx->cq_last_tm_flush;
- events_got = seq - ctx->cq_last_tm_flush;
- if (events_got < events_needed)
- break;
-
- list_del_init(&req->timeout.list);
- io_kill_timeout(req, 0);
- }
- ctx->cq_last_tm_flush = seq;
- spin_unlock_irq(&ctx->timeout_lock);
-}
-
-static __cold void __io_commit_cqring_flush(struct io_ring_ctx *ctx)
-{
- if (ctx->off_timeout_used)
- io_flush_timeouts(ctx);
- if (ctx->drain_active)
- io_queue_deferred(ctx);
-}
-
-static inline void io_commit_cqring(struct io_ring_ctx *ctx)
-{
- if (unlikely(ctx->off_timeout_used || ctx->drain_active))
- __io_commit_cqring_flush(ctx);
- /* order cqe stores with ring update */
- smp_store_release(&ctx->rings->cq.tail, ctx->cached_cq_tail);
-}
-
-static inline bool io_sqring_full(struct io_ring_ctx *ctx)
-{
- struct io_rings *r = ctx->rings;
-
- return READ_ONCE(r->sq.tail) - ctx->cached_sq_head == ctx->sq_entries;
-}
-
-static inline unsigned int __io_cqring_events(struct io_ring_ctx *ctx)
-{
- return ctx->cached_cq_tail - READ_ONCE(ctx->rings->cq.head);
-}
-
-static inline struct io_uring_cqe *io_get_cqe(struct io_ring_ctx *ctx)
-{
- struct io_rings *rings = ctx->rings;
- unsigned tail, mask = ctx->cq_entries - 1;
-
- /*
- * writes to the cq entry need to come after reading head; the
- * control dependency is enough as we're using WRITE_ONCE to
- * fill the cq entry
- */
- if (__io_cqring_events(ctx) == ctx->cq_entries)
- return NULL;
-
- tail = ctx->cached_cq_tail++;
- return &rings->cqes[tail & mask];
-}
-
-static inline bool io_should_trigger_evfd(struct io_ring_ctx *ctx)
-{
- if (likely(!ctx->cq_ev_fd))
- return false;
- if (READ_ONCE(ctx->rings->cq_flags) & IORING_CQ_EVENTFD_DISABLED)
- return false;
- return !ctx->eventfd_async || io_wq_current_is_worker();
-}
-
-/*
- * This should only get called when at least one event has been posted.
- * Some applications rely on the eventfd notification count only changing
- * IFF a new CQE has been added to the CQ ring. There's no depedency on
- * 1:1 relationship between how many times this function is called (and
- * hence the eventfd count) and number of CQEs posted to the CQ ring.
- */
-static void io_cqring_ev_posted(struct io_ring_ctx *ctx)
-{
- /*
- * wake_up_all() may seem excessive, but io_wake_function() and
- * io_should_wake() handle the termination of the loop and only
- * wake as many waiters as we need to.
- */
- if (wq_has_sleeper(&ctx->cq_wait))
- wake_up_all(&ctx->cq_wait);
- if (io_should_trigger_evfd(ctx))
- eventfd_signal(ctx->cq_ev_fd, 1);
-}
-
-static void io_cqring_ev_posted_iopoll(struct io_ring_ctx *ctx)
-{
- /* see waitqueue_active() comment */
- smp_mb();
-
- if (ctx->flags & IORING_SETUP_SQPOLL) {
- if (waitqueue_active(&ctx->cq_wait))
- wake_up_all(&ctx->cq_wait);
- }
- if (io_should_trigger_evfd(ctx))
- eventfd_signal(ctx->cq_ev_fd, 1);
-}
-
-/* Returns true if there are no backlogged entries after the flush */
-static bool __io_cqring_overflow_flush(struct io_ring_ctx *ctx, bool force)
-{
- bool all_flushed, posted;
-
- if (!force && __io_cqring_events(ctx) == ctx->cq_entries)
- return false;
-
- posted = false;
- spin_lock(&ctx->completion_lock);
- while (!list_empty(&ctx->cq_overflow_list)) {
- struct io_uring_cqe *cqe = io_get_cqe(ctx);
- struct io_overflow_cqe *ocqe;
-
- if (!cqe && !force)
- break;
- ocqe = list_first_entry(&ctx->cq_overflow_list,
- struct io_overflow_cqe, list);
- if (cqe)
- memcpy(cqe, &ocqe->cqe, sizeof(*cqe));
- else
- io_account_cq_overflow(ctx);
-
- posted = true;
- list_del(&ocqe->list);
- kfree(ocqe);
- }
-
- all_flushed = list_empty(&ctx->cq_overflow_list);
- if (all_flushed) {
- clear_bit(0, &ctx->check_cq_overflow);
- WRITE_ONCE(ctx->rings->sq_flags,
- ctx->rings->sq_flags & ~IORING_SQ_CQ_OVERFLOW);
- }
-
- if (posted)
- io_commit_cqring(ctx);
- spin_unlock(&ctx->completion_lock);
- if (posted)
- io_cqring_ev_posted(ctx);
- return all_flushed;
-}
-
-static bool io_cqring_overflow_flush(struct io_ring_ctx *ctx)
-{
- bool ret = true;
-
- if (test_bit(0, &ctx->check_cq_overflow)) {
- /* iopoll syncs against uring_lock, not completion_lock */
- if (ctx->flags & IORING_SETUP_IOPOLL)
- mutex_lock(&ctx->uring_lock);
- ret = __io_cqring_overflow_flush(ctx, false);
- if (ctx->flags & IORING_SETUP_IOPOLL)
- mutex_unlock(&ctx->uring_lock);
- }
-
- return ret;
-}
-
-/* must to be called somewhat shortly after putting a request */
-static inline void io_put_task(struct task_struct *task, int nr)
-{
- struct io_uring_task *tctx = task->io_uring;
-
- if (likely(task == current)) {
- tctx->cached_refs += nr;
- } else {
- percpu_counter_sub(&tctx->inflight, nr);
- if (unlikely(atomic_read(&tctx->in_idle)))
- wake_up(&tctx->wait);
- put_task_struct_many(task, nr);
- }
-}
-
-static void io_task_refs_refill(struct io_uring_task *tctx)
-{
- unsigned int refill = -tctx->cached_refs + IO_TCTX_REFS_CACHE_NR;
-
- percpu_counter_add(&tctx->inflight, refill);
- refcount_add(refill, &current->usage);
- tctx->cached_refs += refill;
-}
-
-static inline void io_get_task_refs(int nr)
-{
- struct io_uring_task *tctx = current->io_uring;
-
- tctx->cached_refs -= nr;
- if (unlikely(tctx->cached_refs < 0))
- io_task_refs_refill(tctx);
-}
-
-static bool io_cqring_event_overflow(struct io_ring_ctx *ctx, u64 user_data,
- s32 res, u32 cflags)
-{
- struct io_overflow_cqe *ocqe;
-
- ocqe = kmalloc(sizeof(*ocqe), GFP_ATOMIC | __GFP_ACCOUNT);
- if (!ocqe) {
- /*
- * If we're in ring overflow flush mode, or in task cancel mode,
- * or cannot allocate an overflow entry, then we need to drop it
- * on the floor.
- */
- io_account_cq_overflow(ctx);
- return false;
- }
- if (list_empty(&ctx->cq_overflow_list)) {
- set_bit(0, &ctx->check_cq_overflow);
- WRITE_ONCE(ctx->rings->sq_flags,
- ctx->rings->sq_flags | IORING_SQ_CQ_OVERFLOW);
-
- }
- ocqe->cqe.user_data = user_data;
- ocqe->cqe.res = res;
- ocqe->cqe.flags = cflags;
- list_add_tail(&ocqe->list, &ctx->cq_overflow_list);
- return true;
-}
-
-static inline bool __io_cqring_fill_event(struct io_ring_ctx *ctx, u64 user_data,
- s32 res, u32 cflags)
-{
- struct io_uring_cqe *cqe;
-
- trace_io_uring_complete(ctx, user_data, res, cflags);
-
- /*
- * If we can't get a cq entry, userspace overflowed the
- * submission (by quite a lot). Increment the overflow count in
- * the ring.
- */
- cqe = io_get_cqe(ctx);
- if (likely(cqe)) {
- WRITE_ONCE(cqe->user_data, user_data);
- WRITE_ONCE(cqe->res, res);
- WRITE_ONCE(cqe->flags, cflags);
- return true;
- }
- return io_cqring_event_overflow(ctx, user_data, res, cflags);
-}
-
-/* not as hot to bloat with inlining */
-static noinline bool io_cqring_fill_event(struct io_ring_ctx *ctx, u64 user_data,
- s32 res, u32 cflags)
-{
- return __io_cqring_fill_event(ctx, user_data, res, cflags);
-}
-
-static void io_req_complete_post(struct io_kiocb *req, s32 res,
- u32 cflags)
-{
- struct io_ring_ctx *ctx = req->ctx;
-
- spin_lock(&ctx->completion_lock);
- __io_cqring_fill_event(ctx, req->user_data, res, cflags);
- /*
- * If we're the last reference to this request, add to our locked
- * free_list cache.
- */
- if (req_ref_put_and_test(req)) {
- if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
- if (req->flags & IO_DISARM_MASK)
- io_disarm_next(req);
- if (req->link) {
- io_req_task_queue(req->link);
- req->link = NULL;
- }
- }
- io_req_put_rsrc(req, ctx);
- io_dismantle_req(req);
- io_put_task(req->task, 1);
- wq_list_add_head(&req->comp_list, &ctx->locked_free_list);
- ctx->locked_free_nr++;
- }
- io_commit_cqring(ctx);
- spin_unlock(&ctx->completion_lock);
- io_cqring_ev_posted(ctx);
-}
-
-static inline void io_req_complete_state(struct io_kiocb *req, s32 res,
- u32 cflags)
-{
- req->result = res;
- req->cflags = cflags;
- req->flags |= REQ_F_COMPLETE_INLINE;
-}
-
-static inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags,
- s32 res, u32 cflags)
-{
- if (issue_flags & IO_URING_F_COMPLETE_DEFER)
- io_req_complete_state(req, res, cflags);
- else
- io_req_complete_post(req, res, cflags);
-}
-
-static inline void io_req_complete(struct io_kiocb *req, s32 res)
-{
- __io_req_complete(req, 0, res, 0);
-}
-
-static void io_req_complete_failed(struct io_kiocb *req, s32 res)
-{
- req_set_fail(req);
- io_req_complete_post(req, res, 0);
-}
-
-static void io_req_complete_fail_submit(struct io_kiocb *req)
-{
- /*
- * We don't submit, fail them all, for that replace hardlinks with
- * normal links. Extra REQ_F_LINK is tolerated.
- */
- req->flags &= ~REQ_F_HARDLINK;
- req->flags |= REQ_F_LINK;
- io_req_complete_failed(req, req->result);
-}
-
-/*
- * Don't initialise the fields below on every allocation, but do that in
- * advance and keep them valid across allocations.
- */
-static void io_preinit_req(struct io_kiocb *req, struct io_ring_ctx *ctx)
-{
- req->ctx = ctx;
- req->link = NULL;
- req->async_data = NULL;
- /* not necessary, but safer to zero */
- req->result = 0;
-}
-
-static void io_flush_cached_locked_reqs(struct io_ring_ctx *ctx,
- struct io_submit_state *state)
-{
- spin_lock(&ctx->completion_lock);
- wq_list_splice(&ctx->locked_free_list, &state->free_list);
- ctx->locked_free_nr = 0;
- spin_unlock(&ctx->completion_lock);
-}
-
-/* Returns true IFF there are requests in the cache */
-static bool io_flush_cached_reqs(struct io_ring_ctx *ctx)
-{
- struct io_submit_state *state = &ctx->submit_state;
-
- /*
- * If we have more than a batch's worth of requests in our IRQ side
- * locked cache, grab the lock and move them over to our submission
- * side cache.
- */
- if (READ_ONCE(ctx->locked_free_nr) > IO_COMPL_BATCH)
- io_flush_cached_locked_reqs(ctx, state);
- return !!state->free_list.next;
-}
-
-/*
- * A request might get retired back into the request caches even before opcode
- * handlers and io_issue_sqe() are done with it, e.g. inline completion path.
- * Because of that, io_alloc_req() should be called only under ->uring_lock
- * and with extra caution to not get a request that is still worked on.
- */
-static __cold bool __io_alloc_req_refill(struct io_ring_ctx *ctx)
- __must_hold(&ctx->uring_lock)
-{
- struct io_submit_state *state = &ctx->submit_state;
- gfp_t gfp = GFP_KERNEL | __GFP_NOWARN;
- void *reqs[IO_REQ_ALLOC_BATCH];
- struct io_kiocb *req;
- int ret, i;
-
- if (likely(state->free_list.next || io_flush_cached_reqs(ctx)))
- return true;
-
- ret = kmem_cache_alloc_bulk(req_cachep, gfp, ARRAY_SIZE(reqs), reqs);
-
- /*
- * Bulk alloc is all-or-nothing. If we fail to get a batch,
- * retry single alloc to be on the safe side.
- */
- if (unlikely(ret <= 0)) {
- reqs[0] = kmem_cache_alloc(req_cachep, gfp);
- if (!reqs[0])
- return false;
- ret = 1;
- }
-
- percpu_ref_get_many(&ctx->refs, ret);
- for (i = 0; i < ret; i++) {
- req = reqs[i];
-
- io_preinit_req(req, ctx);
- wq_stack_add_head(&req->comp_list, &state->free_list);
- }
- return true;
-}
-
-static inline bool io_alloc_req_refill(struct io_ring_ctx *ctx)
-{
- if (unlikely(!ctx->submit_state.free_list.next))
- return __io_alloc_req_refill(ctx);
- return true;
-}
-
-static inline struct io_kiocb *io_alloc_req(struct io_ring_ctx *ctx)
-{
- struct io_wq_work_node *node;
-
- node = wq_stack_extract(&ctx->submit_state.free_list);
- return container_of(node, struct io_kiocb, comp_list);
-}
-
-static inline void io_put_file(struct file *file)
-{
- if (file)
- fput(file);
-}
-
-static inline void io_dismantle_req(struct io_kiocb *req)
-{
- unsigned int flags = req->flags;
-
- if (unlikely(flags & IO_REQ_CLEAN_FLAGS))
- io_clean_op(req);
- if (!(flags & REQ_F_FIXED_FILE))
- io_put_file(req->file);
-}
-
-static __cold void __io_free_req(struct io_kiocb *req)
-{
- struct io_ring_ctx *ctx = req->ctx;
-
- io_req_put_rsrc(req, ctx);
- io_dismantle_req(req);
- io_put_task(req->task, 1);
-
- spin_lock(&ctx->completion_lock);
- wq_list_add_head(&req->comp_list, &ctx->locked_free_list);
- ctx->locked_free_nr++;
- spin_unlock(&ctx->completion_lock);
-}
-
-static inline void io_remove_next_linked(struct io_kiocb *req)
-{
- struct io_kiocb *nxt = req->link;
-
- req->link = nxt->link;
- nxt->link = NULL;
-}
-
-static bool io_kill_linked_timeout(struct io_kiocb *req)
- __must_hold(&req->ctx->completion_lock)
- __must_hold(&req->ctx->timeout_lock)
-{
- struct io_kiocb *link = req->link;
-
- if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
- struct io_timeout_data *io = link->async_data;
-
- io_remove_next_linked(req);
- link->timeout.head = NULL;
- if (hrtimer_try_to_cancel(&io->timer) != -1) {
- list_del(&link->timeout.list);
- io_cqring_fill_event(link->ctx, link->user_data,
- -ECANCELED, 0);
- io_put_req_deferred(link);
- return true;
- }
- }
- return false;
-}
-
-static void io_fail_links(struct io_kiocb *req)
- __must_hold(&req->ctx->completion_lock)
-{
- struct io_kiocb *nxt, *link = req->link;
-
- req->link = NULL;
- while (link) {
- long res = -ECANCELED;
-
- if (link->flags & REQ_F_FAIL)
- res = link->result;
-
- nxt = link->link;
- link->link = NULL;
-
- trace_io_uring_fail_link(req, link);
- io_cqring_fill_event(link->ctx, link->user_data, res, 0);
- io_put_req_deferred(link);
- link = nxt;
- }
-}
-
-static bool io_disarm_next(struct io_kiocb *req)
- __must_hold(&req->ctx->completion_lock)
-{
- bool posted = false;
-
- if (req->flags & REQ_F_ARM_LTIMEOUT) {
- struct io_kiocb *link = req->link;
-
- req->flags &= ~REQ_F_ARM_LTIMEOUT;
- if (link && link->opcode == IORING_OP_LINK_TIMEOUT) {
- io_remove_next_linked(req);
- io_cqring_fill_event(link->ctx, link->user_data,
- -ECANCELED, 0);
- io_put_req_deferred(link);
- posted = true;
- }
- } else if (req->flags & REQ_F_LINK_TIMEOUT) {
- struct io_ring_ctx *ctx = req->ctx;
-
- spin_lock_irq(&ctx->timeout_lock);
- posted = io_kill_linked_timeout(req);
- spin_unlock_irq(&ctx->timeout_lock);
- }
- if (unlikely((req->flags & REQ_F_FAIL) &&
- !(req->flags & REQ_F_HARDLINK))) {
- posted |= (req->link != NULL);
- io_fail_links(req);
- }
- return posted;
-}
-
-static void __io_req_find_next_prep(struct io_kiocb *req)
-{
- struct io_ring_ctx *ctx = req->ctx;
- bool posted;
-
- spin_lock(&ctx->completion_lock);
- posted = io_disarm_next(req);
- if (posted)
- io_commit_cqring(req->ctx);
- spin_unlock(&ctx->completion_lock);
- if (posted)
- io_cqring_ev_posted(ctx);
-}
-
-static inline struct io_kiocb *io_req_find_next(struct io_kiocb *req)
-{
- struct io_kiocb *nxt;
-
- if (likely(!(req->flags & (REQ_F_LINK|REQ_F_HARDLINK))))
- return NULL;
- /*
- * If LINK is set, we have dependent requests in this chain. If we
- * didn't fail this request, queue the first one up, moving any other
- * dependencies to the next request. In case of failure, fail the rest
- * of the chain.
- */
- if (unlikely(req->flags & IO_DISARM_MASK))
- __io_req_find_next_prep(req);
- nxt = req->link;
- req->link = NULL;
- return nxt;
-}
-
-static void ctx_flush_and_put(struct io_ring_ctx *ctx, bool *locked)
-{
- if (!ctx)
- return;
- if (*locked) {
- io_submit_flush_completions(ctx);
- mutex_unlock(&ctx->uring_lock);
- *locked = false;
- }
- percpu_ref_put(&ctx->refs);
-}
-
-static void tctx_task_work(struct callback_head *cb)
-{
- bool locked = false;
- struct io_ring_ctx *ctx = NULL;
- struct io_uring_task *tctx = container_of(cb, struct io_uring_task,
- task_work);
-
- while (1) {
- struct io_wq_work_node *node;
-
- if (!tctx->task_list.first && locked)
- io_submit_flush_completions(ctx);
-
- spin_lock_irq(&tctx->task_lock);
- node = tctx->task_list.first;
- INIT_WQ_LIST(&tctx->task_list);
- if (!node)
- tctx->task_running = false;
- spin_unlock_irq(&tctx->task_lock);
- if (!node)
- break;
-
- do {
- struct io_wq_work_node *next = node->next;
- struct io_kiocb *req = container_of(node, struct io_kiocb,
- io_task_work.node);
-
- if (req->ctx != ctx) {
- ctx_flush_and_put(ctx, &locked);
- ctx = req->ctx;
- /* if not contended, grab and improve batching */
- locked = mutex_trylock(&ctx->uring_lock);
- percpu_ref_get(&ctx->refs);
- }
- req->io_task_work.func(req, &locked);
- node = next;
- } while (node);
-
- cond_resched();
- }
-
- ctx_flush_and_put(ctx, &locked);
-}
-
-static void io_req_task_work_add(struct io_kiocb *req)
-{
- struct task_struct *tsk = req->task;
- struct io_uring_task *tctx = tsk->io_uring;
- enum task_work_notify_mode notify;
- struct io_wq_work_node *node;
- unsigned long flags;
- bool running;
-
- WARN_ON_ONCE(!tctx);
-
- spin_lock_irqsave(&tctx->task_lock, flags);
- wq_list_add_tail(&req->io_task_work.node, &tctx->task_list);
- running = tctx->task_running;
- if (!running)
- tctx->task_running = true;
- spin_unlock_irqrestore(&tctx->task_lock, flags);
-
- /* task_work already pending, we're done */
- if (running)
- return;
-
- /*
- * SQPOLL kernel thread doesn't need notification, just a wakeup. For
- * all other cases, use TWA_SIGNAL unconditionally to ensure we're
- * processing task_work. There's no reliable way to tell if TWA_RESUME
- * will do the job.
- */
- notify = (req->ctx->flags & IORING_SETUP_SQPOLL) ? TWA_NONE : TWA_SIGNAL;
- if (likely(!task_work_add(tsk, &tctx->task_work, notify))) {
- if (notify == TWA_NONE)
- wake_up_process(tsk);
- return;
- }
-
- spin_lock_irqsave(&tctx->task_lock, flags);
- tctx->task_running = false;
- node = tctx->task_list.first;
- INIT_WQ_LIST(&tctx->task_list);
- spin_unlock_irqrestore(&tctx->task_lock, flags);
-
- while (node) {
- req = container_of(node, struct io_kiocb, io_task_work.node);
- node = node->next;
- if (llist_add(&req->io_task_work.fallback_node,
- &req->ctx->fallback_llist))
- schedule_delayed_work(&req->ctx->fallback_work, 1);
- }
-}
-
-static void io_req_task_cancel(struct io_kiocb *req, bool *locked)
-{
- struct io_ring_ctx *ctx = req->ctx;
-
- /* not needed for normal modes, but SQPOLL depends on it */
- io_tw_lock(ctx, locked);
- io_req_complete_failed(req, req->result);
-}
-
-static void io_req_task_submit(struct io_kiocb *req, bool *locked)
-{
- struct io_ring_ctx *ctx = req->ctx;
-
- io_tw_lock(ctx, locked);
- /* req->task == current here, checking PF_EXITING is safe */
- if (likely(!(req->task->flags & PF_EXITING)))
- __io_queue_sqe(req);
- else
- io_req_complete_failed(req, -EFAULT);
-}
-
-static void io_req_task_queue_fail(struct io_kiocb *req, int ret)
-{
- req->result = ret;
- req->io_task_work.func = io_req_task_cancel;
- io_req_task_work_add(req);
-}
-
-static void io_req_task_queue(struct io_kiocb *req)
-{
- req->io_task_work.func = io_req_task_submit;
- io_req_task_work_add(req);
-}
-
-static void io_req_task_queue_reissue(struct io_kiocb *req)
-{
- req->io_task_work.func = io_queue_async_work;
- io_req_task_work_add(req);
-}
-
-static inline void io_queue_next(struct io_kiocb *req)
-{
- struct io_kiocb *nxt = io_req_find_next(req);
-
- if (nxt)
- io_req_task_queue(nxt);
-}
-
-static void io_free_req(struct io_kiocb *req)
-{
- io_queue_next(req);
- __io_free_req(req);
-}
-
-static void io_free_req_work(struct io_kiocb *req, bool *locked)
-{
- io_free_req(req);
-}
-
-static void io_free_batch_list(struct io_ring_ctx *ctx,
- struct io_wq_work_node *node)
- __must_hold(&ctx->uring_lock)
-{
- struct task_struct *task = NULL;
- int task_refs = 0;
-
- do {
- struct io_kiocb *req = container_of(node, struct io_kiocb,
- comp_list);
-
- if (unlikely(req->flags & REQ_F_REFCOUNT)) {
- node = req->comp_list.next;
- if (!req_ref_put_and_test(req))
- continue;
- }
-
- io_req_put_rsrc_locked(req, ctx);
- io_queue_next(req);
- io_dismantle_req(req);
-
- if (req->task != task) {
- if (task)
- io_put_task(task, task_refs);
- task = req->task;
- task_refs = 0;
- }
- task_refs++;
- node = req->comp_list.next;
- wq_stack_add_head(&req->comp_list, &ctx->submit_state.free_list);
- } while (node);
-
- if (task)
- io_put_task(task, task_refs);
-}
-
-static void __io_submit_flush_completions(struct io_ring_ctx *ctx)
- __must_hold(&ctx->uring_lock)
-{
- struct io_wq_work_node *node, *prev;
- struct io_submit_state *state = &ctx->submit_state;
-
- spin_lock(&ctx->completion_lock);
- wq_list_for_each(node, prev, &state->compl_reqs) {
- struct io_kiocb *req = container_of(node, struct io_kiocb,
- comp_list);
-
- __io_cqring_fill_event(ctx, req->user_data, req->result,
- req->cflags);
- }
- io_commit_cqring(ctx);
- spin_unlock(&ctx->completion_lock);
- io_cqring_ev_posted(ctx);
-
- io_free_batch_list(ctx, state->compl_reqs.first);
- INIT_WQ_LIST(&state->compl_reqs);
-}
-
-/*
- * Drop reference to request, return next in chain (if there is one) if this
- * was the last reference to this request.
- */
-static inline struct io_kiocb *io_put_req_find_next(struct io_kiocb *req)
-{
- struct io_kiocb *nxt = NULL;
-
- if (req_ref_put_and_test(req)) {
- nxt = io_req_find_next(req);
- __io_free_req(req);
- }
- return nxt;
-}
-
-static inline void io_put_req(struct io_kiocb *req)
-{
- if (req_ref_put_and_test(req))
- io_free_req(req);
-}
-
-static inline void io_put_req_deferred(struct io_kiocb *req)
-{
- if (req_ref_put_and_test(req)) {
- req->io_task_work.func = io_free_req_work;
- io_req_task_work_add(req);
- }
-}
-
-static unsigned io_cqring_events(struct io_ring_ctx *ctx)
-{
- /* See comment at the top of this file */
- smp_rmb();
- return __io_cqring_events(ctx);
-}
-
-static inline unsigned int io_sqring_entries(struct io_ring_ctx *ctx)
-{
- struct io_rings *rings = ctx->rings;
-
- /* make sure SQ entry isn't read before tail */
- return smp_load_acquire(&rings->sq.tail) - ctx->cached_sq_head;
-}
-
-static unsigned int io_put_kbuf(struct io_kiocb *req, struct io_buffer *kbuf)
-{
- unsigned int cflags;
-
- cflags = kbuf->bid << IORING_CQE_BUFFER_SHIFT;
- cflags |= IORING_CQE_F_BUFFER;
- req->flags &= ~REQ_F_BUFFER_SELECTED;
- kfree(kbuf);
- return cflags;
-}
-
-static inline unsigned int io_put_rw_kbuf(struct io_kiocb *req)
-{
- if (likely(!(req->flags & REQ_F_BUFFER_SELECTED)))
- return 0;
- return io_put_kbuf(req, req->kbuf);
-}
-
-static inline bool io_run_task_work(void)
-{
- if (test_thread_flag(TIF_NOTIFY_SIGNAL) || current->task_works) {
- __set_current_state(TASK_RUNNING);
- tracehook_notify_signal();
- return true;
- }
-
- return false;
-}
-
-static int io_do_iopoll(struct io_ring_ctx *ctx, bool force_nonspin)
-{
- struct io_wq_work_node *pos, *start, *prev;
- unsigned int poll_flags = BLK_POLL_NOSLEEP;
- DEFINE_IO_COMP_BATCH(iob);
- int nr_events = 0;
-
- /*
- * Only spin for completions if we don't have multiple devices hanging
- * off our complete list.
- */
- if (ctx->poll_multi_queue || force_nonspin)
- poll_flags |= BLK_POLL_ONESHOT;
-
- wq_list_for_each(pos, start, &ctx->iopoll_list) {
- struct io_kiocb *req = container_of(pos, struct io_kiocb, comp_list);
- struct kiocb *kiocb = &req->rw.kiocb;
- int ret;
-
- /*
- * Move completed and retryable entries to our local lists.
- * If we find a request that requires polling, break out
- * and complete those lists first, if we have entries there.
- */
- if (READ_ONCE(req->iopoll_completed))
- break;
-
- ret = kiocb->ki_filp->f_op->iopoll(kiocb, &iob, poll_flags);
- if (unlikely(ret < 0))
- return ret;
- else if (ret)
- poll_flags |= BLK_POLL_ONESHOT;
-
- /* iopoll may have completed current req */
- if (!rq_list_empty(iob.req_list) ||
- READ_ONCE(req->iopoll_completed))
- break;
- }
-
- if (!rq_list_empty(iob.req_list))
- iob.complete(&iob);
- else if (!pos)
- return 0;
-
- prev = start;
- wq_list_for_each_resume(pos, prev) {
- struct io_kiocb *req = container_of(pos, struct io_kiocb, comp_list);
-
- /* order with io_complete_rw_iopoll(), e.g. ->result updates */
- if (!smp_load_acquire(&req->iopoll_completed))
- break;
- __io_cqring_fill_event(ctx, req->user_data, req->result,
- io_put_rw_kbuf(req));
- nr_events++;
- }
-
- if (unlikely(!nr_events))
- return 0;
-
- io_commit_cqring(ctx);
- io_cqring_ev_posted_iopoll(ctx);
- pos = start ? start->next : ctx->iopoll_list.first;
- wq_list_cut(&ctx->iopoll_list, prev, start);
- io_free_batch_list(ctx, pos);
- return nr_events;
-}
-
-/*
- * We can't just wait for polled events to come to us, we have to actively
- * find and complete them.
- */
-static __cold void io_iopoll_try_reap_events(struct io_ring_ctx *ctx)
-{
- if (!(ctx->flags & IORING_SETUP_IOPOLL))
- return;
-
- mutex_lock(&ctx->uring_lock);
- while (!wq_list_empty(&ctx->iopoll_list)) {
- /* let it sleep and repeat later if can't complete a request */
- if (io_do_iopoll(ctx, true) == 0)
- break;
- /*
- * Ensure we allow local-to-the-cpu processing to take place,
- * in this case we need to ensure that we reap all events.
- * Also let task_work, etc. to progress by releasing the mutex
- */
- if (need_resched()) {
- mutex_unlock(&ctx->uring_lock);
- cond_resched();
- mutex_lock(&ctx->uring_lock);
- }
- }
- mutex_unlock(&ctx->uring_lock);
-}
-
-static int io_iopoll_check(struct io_ring_ctx *ctx, long min)
-{
- unsigned int nr_events = 0;
- int ret = 0;
-
- /*
- * We disallow the app entering submit/complete with polling, but we
- * still need to lock the ring to prevent racing with polled issue
- * that got punted to a workqueue.
- */
- mutex_lock(&ctx->uring_lock);
- /*
- * Don't enter poll loop if we already have events pending.
- * If we do, we can potentially be spinning for commands that
- * already triggered a CQE (eg in error).
- */
- if (test_bit(0, &ctx->check_cq_overflow))
- __io_cqring_overflow_flush(ctx, false);
- if (io_cqring_events(ctx))
- goto out;
- do {
- /*
- * If a submit got punted to a workqueue, we can have the
- * application entering polling for a command before it gets
- * issued. That app will hold the uring_lock for the duration
- * of the poll right here, so we need to take a breather every
- * now and then to ensure that the issue has a chance to add
- * the poll to the issued list. Otherwise we can spin here
- * forever, while the workqueue is stuck trying to acquire the
- * very same mutex.
- */
- if (wq_list_empty(&ctx->iopoll_list)) {
- u32 tail = ctx->cached_cq_tail;
-
- mutex_unlock(&ctx->uring_lock);
- io_run_task_work();
- mutex_lock(&ctx->uring_lock);
-
- /* some requests don't go through iopoll_list */
- if (tail != ctx->cached_cq_tail ||
- wq_list_empty(&ctx->iopoll_list))
- break;
- }
- ret = io_do_iopoll(ctx, !min);
- if (ret < 0)
- break;
- nr_events += ret;
- ret = 0;
- } while (nr_events < min && !need_resched());
-out:
- mutex_unlock(&ctx->uring_lock);
- return ret;
-}
-
-static void kiocb_end_write(struct io_kiocb *req)
-{
- /*
- * Tell lockdep we inherited freeze protection from submission
- * thread.
- */
- if (req->flags & REQ_F_ISREG) {
- struct super_block *sb = file_inode(req->file)->i_sb;
-
- __sb_writers_acquired(sb, SB_FREEZE_WRITE);
- sb_end_write(sb);
- }
-}
-
-#ifdef CONFIG_BLOCK
-static bool io_resubmit_prep(struct io_kiocb *req)
-{
- struct io_async_rw *rw = req->async_data;
-
- if (!req_has_async_data(req))
- return !io_req_prep_async(req);
- iov_iter_restore(&rw->s.iter, &rw->s.iter_state);
- return true;
-}
-
-static bool io_rw_should_reissue(struct io_kiocb *req)
-{
- umode_t mode = file_inode(req->file)->i_mode;
- struct io_ring_ctx *ctx = req->ctx;
-
- if (!S_ISBLK(mode) && !S_ISREG(mode))
- return false;
- if ((req->flags & REQ_F_NOWAIT) || (io_wq_current_is_worker() &&
- !(ctx->flags & IORING_SETUP_IOPOLL)))
- return false;
- /*
- * If ref is dying, we might be running poll reap from the exit work.
- * Don't attempt to reissue from that path, just let it fail with
- * -EAGAIN.
- */
- if (percpu_ref_is_dying(&ctx->refs))
- return false;
- /*
- * Play it safe and assume not safe to re-import and reissue if we're
- * not in the original thread group (or in task context).
- */
- if (!same_thread_group(req->task, current) || !in_task())
- return false;
- return true;
-}
-#else
-static bool io_resubmit_prep(struct io_kiocb *req)
-{
- return false;
-}
-static bool io_rw_should_reissue(struct io_kiocb *req)
-{
- return false;
-}
-#endif
-
-static bool __io_complete_rw_common(struct io_kiocb *req, long res)
-{
- if (req->rw.kiocb.ki_flags & IOCB_WRITE)
- kiocb_end_write(req);
- if (unlikely(res != req->result)) {
- if ((res == -EAGAIN || res == -EOPNOTSUPP) &&
- io_rw_should_reissue(req)) {
- req->flags |= REQ_F_REISSUE;
- return true;
- }
- req_set_fail(req);
- req->result = res;
- }
- return false;
-}
-
-static void io_req_task_complete(struct io_kiocb *req, bool *locked)
-{
- unsigned int cflags = io_put_rw_kbuf(req);
- int res = req->result;
-
- if (*locked) {
- io_req_complete_state(req, res, cflags);
- io_req_add_compl_list(req);
- } else {
- io_req_complete_post(req, res, cflags);
- }
-}
-
-static void __io_complete_rw(struct io_kiocb *req, long res, long res2,
- unsigned int issue_flags)
-{
- if (__io_complete_rw_common(req, res))
- return;
- __io_req_complete(req, issue_flags, req->result, io_put_rw_kbuf(req));
-}
-
-static void io_complete_rw(struct kiocb *kiocb, long res)
-{
- struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
-
- if (__io_complete_rw_common(req, res))
- return;
- req->result = res;
- req->io_task_work.func = io_req_task_complete;
- io_req_task_work_add(req);
-}
-
-static void io_complete_rw_iopoll(struct kiocb *kiocb, long res)
-{
- struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
-
- if (kiocb->ki_flags & IOCB_WRITE)
- kiocb_end_write(req);
- if (unlikely(res != req->result)) {
- if (res == -EAGAIN && io_rw_should_reissue(req)) {
- req->flags |= REQ_F_REISSUE;
- return;
- }
- req->result = res;
- }
-
- /* order with io_iopoll_complete() checking ->iopoll_completed */
- smp_store_release(&req->iopoll_completed, 1);
-}
-
-/*
- * After the iocb has been issued, it's safe to be found on the poll list.
- * Adding the kiocb to the list AFTER submission ensures that we don't
- * find it from a io_do_iopoll() thread before the issuer is done
- * accessing the kiocb cookie.
- */
-static void io_iopoll_req_issued(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_ring_ctx *ctx = req->ctx;
- const bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
-
- /* workqueue context doesn't hold uring_lock, grab it now */
- if (unlikely(needs_lock))
- mutex_lock(&ctx->uring_lock);
-
- /*
- * Track whether we have multiple files in our lists. This will impact
- * how we do polling eventually, not spinning if we're on potentially
- * different devices.
- */
- if (wq_list_empty(&ctx->iopoll_list)) {
- ctx->poll_multi_queue = false;
- } else if (!ctx->poll_multi_queue) {
- struct io_kiocb *list_req;
-
- list_req = container_of(ctx->iopoll_list.first, struct io_kiocb,
- comp_list);
- if (list_req->file != req->file)
- ctx->poll_multi_queue = true;
- }
-
- /*
- * For fast devices, IO may have already completed. If it has, add
- * it to the front so we find it first.
- */
- if (READ_ONCE(req->iopoll_completed))
- wq_list_add_head(&req->comp_list, &ctx->iopoll_list);
- else
- wq_list_add_tail(&req->comp_list, &ctx->iopoll_list);
-
- if (unlikely(needs_lock)) {
- /*
- * If IORING_SETUP_SQPOLL is enabled, sqes are either handle
- * in sq thread task context or in io worker task context. If
- * current task context is sq thread, we don't need to check
- * whether should wake up sq thread.
- */
- if ((ctx->flags & IORING_SETUP_SQPOLL) &&
- wq_has_sleeper(&ctx->sq_data->wait))
- wake_up(&ctx->sq_data->wait);
-
- mutex_unlock(&ctx->uring_lock);
- }
-}
-
-static bool io_bdev_nowait(struct block_device *bdev)
-{
- return !bdev || blk_queue_nowait(bdev_get_queue(bdev));
-}
-
-/*
- * If we tracked the file through the SCM inflight mechanism, we could support
- * any file. For now, just ensure that anything potentially problematic is done
- * inline.
- */
-static bool __io_file_supports_nowait(struct file *file, umode_t mode)
-{
- if (S_ISBLK(mode)) {
- if (IS_ENABLED(CONFIG_BLOCK) &&
- io_bdev_nowait(I_BDEV(file->f_mapping->host)))
- return true;
- return false;
- }
- if (S_ISSOCK(mode))
- return true;
- if (S_ISREG(mode)) {
- if (IS_ENABLED(CONFIG_BLOCK) &&
- io_bdev_nowait(file->f_inode->i_sb->s_bdev) &&
- file->f_op != &io_uring_fops)
- return true;
- return false;
- }
-
- /* any ->read/write should understand O_NONBLOCK */
- if (file->f_flags & O_NONBLOCK)
- return true;
- return file->f_mode & FMODE_NOWAIT;
-}
-
-/*
- * If we tracked the file through the SCM inflight mechanism, we could support
- * any file. For now, just ensure that anything potentially problematic is done
- * inline.
- */
-static unsigned int io_file_get_flags(struct file *file)
-{
- umode_t mode = file_inode(file)->i_mode;
- unsigned int res = 0;
-
- if (S_ISREG(mode))
- res |= FFS_ISREG;
- if (__io_file_supports_nowait(file, mode))
- res |= FFS_NOWAIT;
- return res;
-}
-
-static inline bool io_file_supports_nowait(struct io_kiocb *req)
-{
- return req->flags & REQ_F_SUPPORT_NOWAIT;
-}
-
-static int io_prep_rw(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- struct io_ring_ctx *ctx = req->ctx;
- struct kiocb *kiocb = &req->rw.kiocb;
- struct file *file = req->file;
- unsigned ioprio;
- int ret;
-
- if (!io_req_ffs_set(req))
- req->flags |= io_file_get_flags(file) << REQ_F_SUPPORT_NOWAIT_BIT;
-
- kiocb->ki_pos = READ_ONCE(sqe->off);
- if (kiocb->ki_pos == -1) {
- if (!(file->f_mode & FMODE_STREAM)) {
- req->flags |= REQ_F_CUR_POS;
- kiocb->ki_pos = file->f_pos;
- } else {
- kiocb->ki_pos = 0;
- }
- }
- kiocb->ki_flags = iocb_flags(file);
- ret = kiocb_set_rw_flags(kiocb, READ_ONCE(sqe->rw_flags));
- if (unlikely(ret))
- return ret;
-
- /*
- * If the file is marked O_NONBLOCK, still allow retry for it if it
- * supports async. Otherwise it's impossible to use O_NONBLOCK files
- * reliably. If not, or it IOCB_NOWAIT is set, don't retry.
- */
- if ((kiocb->ki_flags & IOCB_NOWAIT) ||
- ((file->f_flags & O_NONBLOCK) && !io_file_supports_nowait(req)))
- req->flags |= REQ_F_NOWAIT;
-
- if (ctx->flags & IORING_SETUP_IOPOLL) {
- if (!(kiocb->ki_flags & IOCB_DIRECT) || !file->f_op->iopoll)
- return -EOPNOTSUPP;
-
- kiocb->ki_flags |= IOCB_HIPRI | IOCB_ALLOC_CACHE;
- kiocb->ki_complete = io_complete_rw_iopoll;
- req->iopoll_completed = 0;
- } else {
- if (kiocb->ki_flags & IOCB_HIPRI)
- return -EINVAL;
- kiocb->ki_complete = io_complete_rw;
- }
-
- ioprio = READ_ONCE(sqe->ioprio);
- if (ioprio) {
- ret = ioprio_check_cap(ioprio);
- if (ret)
- return ret;
-
- kiocb->ki_ioprio = ioprio;
- } else {
- kiocb->ki_ioprio = get_current_ioprio();
- }
-
- req->imu = NULL;
- req->rw.addr = READ_ONCE(sqe->addr);
- req->rw.len = READ_ONCE(sqe->len);
- req->buf_index = READ_ONCE(sqe->buf_index);
- return 0;
-}
-
-static inline void io_rw_done(struct kiocb *kiocb, ssize_t ret)
-{
- switch (ret) {
- case -EIOCBQUEUED:
- break;
- case -ERESTARTSYS:
- case -ERESTARTNOINTR:
- case -ERESTARTNOHAND:
- case -ERESTART_RESTARTBLOCK:
- /*
- * We can't just restart the syscall, since previously
- * submitted sqes may already be in progress. Just fail this
- * IO with EINTR.
- */
- ret = -EINTR;
- fallthrough;
- default:
- kiocb->ki_complete(kiocb, ret);
- }
-}
-
-static void kiocb_done(struct kiocb *kiocb, ssize_t ret,
- unsigned int issue_flags)
-{
- struct io_kiocb *req = container_of(kiocb, struct io_kiocb, rw.kiocb);
- struct io_async_rw *io = req->async_data;
-
- /* add previously done IO, if any */
- if (req_has_async_data(req) && io->bytes_done > 0) {
- if (ret < 0)
- ret = io->bytes_done;
- else
- ret += io->bytes_done;
- }
-
- if (req->flags & REQ_F_CUR_POS)
- req->file->f_pos = kiocb->ki_pos;
- if (ret >= 0 && (kiocb->ki_complete == io_complete_rw))
- __io_complete_rw(req, ret, 0, issue_flags);
- else
- io_rw_done(kiocb, ret);
-
- if (req->flags & REQ_F_REISSUE) {
- req->flags &= ~REQ_F_REISSUE;
- if (io_resubmit_prep(req)) {
- io_req_task_queue_reissue(req);
- } else {
- unsigned int cflags = io_put_rw_kbuf(req);
- struct io_ring_ctx *ctx = req->ctx;
-
- req_set_fail(req);
- if (issue_flags & IO_URING_F_UNLOCKED) {
- mutex_lock(&ctx->uring_lock);
- __io_req_complete(req, issue_flags, ret, cflags);
- mutex_unlock(&ctx->uring_lock);
- } else {
- __io_req_complete(req, issue_flags, ret, cflags);
- }
- }
- }
-}
-
-static int __io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter,
- struct io_mapped_ubuf *imu)
-{
- size_t len = req->rw.len;
- u64 buf_end, buf_addr = req->rw.addr;
- size_t offset;
-
- if (unlikely(check_add_overflow(buf_addr, (u64)len, &buf_end)))
- return -EFAULT;
- /* not inside the mapped region */
- if (unlikely(buf_addr < imu->ubuf || buf_end > imu->ubuf_end))
- return -EFAULT;
-
- /*
- * May not be a start of buffer, set size appropriately
- * and advance us to the beginning.
- */
- offset = buf_addr - imu->ubuf;
- iov_iter_bvec(iter, rw, imu->bvec, imu->nr_bvecs, offset + len);
-
- if (offset) {
- /*
- * Don't use iov_iter_advance() here, as it's really slow for
- * using the latter parts of a big fixed buffer - it iterates
- * over each segment manually. We can cheat a bit here, because
- * we know that:
- *
- * 1) it's a BVEC iter, we set it up
- * 2) all bvecs are PAGE_SIZE in size, except potentially the
- * first and last bvec
- *
- * So just find our index, and adjust the iterator afterwards.
- * If the offset is within the first bvec (or the whole first
- * bvec, just use iov_iter_advance(). This makes it easier
- * since we can just skip the first segment, which may not
- * be PAGE_SIZE aligned.
- */
- const struct bio_vec *bvec = imu->bvec;
-
- if (offset <= bvec->bv_len) {
- iov_iter_advance(iter, offset);
- } else {
- unsigned long seg_skip;
-
- /* skip first vec */
- offset -= bvec->bv_len;
- seg_skip = 1 + (offset >> PAGE_SHIFT);
-
- iter->bvec = bvec + seg_skip;
- iter->nr_segs -= seg_skip;
- iter->count -= bvec->bv_len + offset;
- iter->iov_offset = offset & ~PAGE_MASK;
- }
- }
-
- return 0;
-}
-
-static int io_import_fixed(struct io_kiocb *req, int rw, struct iov_iter *iter)
-{
- struct io_mapped_ubuf *imu = req->imu;
- u16 index, buf_index = req->buf_index;
-
- if (likely(!imu)) {
- struct io_ring_ctx *ctx = req->ctx;
-
- if (unlikely(buf_index >= ctx->nr_user_bufs))
- return -EFAULT;
- io_req_set_rsrc_node(req, ctx);
- index = array_index_nospec(buf_index, ctx->nr_user_bufs);
- imu = READ_ONCE(ctx->user_bufs[index]);
- req->imu = imu;
- }
- return __io_import_fixed(req, rw, iter, imu);
-}
-
-static void io_ring_submit_unlock(struct io_ring_ctx *ctx, bool needs_lock)
-{
- if (needs_lock)
- mutex_unlock(&ctx->uring_lock);
-}
-
-static void io_ring_submit_lock(struct io_ring_ctx *ctx, bool needs_lock)
-{
- /*
- * "Normal" inline submissions always hold the uring_lock, since we
- * grab it from the system call. Same is true for the SQPOLL offload.
- * The only exception is when we've detached the request and issue it
- * from an async worker thread, grab the lock for that case.
- */
- if (needs_lock)
- mutex_lock(&ctx->uring_lock);
-}
-
-static struct io_buffer *io_buffer_select(struct io_kiocb *req, size_t *len,
- int bgid, unsigned int issue_flags)
-{
- struct io_buffer *kbuf = req->kbuf;
- struct io_buffer *head;
- bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
-
- if (req->flags & REQ_F_BUFFER_SELECTED)
- return kbuf;
-
- io_ring_submit_lock(req->ctx, needs_lock);
-
- lockdep_assert_held(&req->ctx->uring_lock);
-
- head = xa_load(&req->ctx->io_buffers, bgid);
- if (head) {
- if (!list_empty(&head->list)) {
- kbuf = list_last_entry(&head->list, struct io_buffer,
- list);
- list_del(&kbuf->list);
- } else {
- kbuf = head;
- xa_erase(&req->ctx->io_buffers, bgid);
- }
- if (*len > kbuf->len)
- *len = kbuf->len;
- req->flags |= REQ_F_BUFFER_SELECTED;
- req->kbuf = kbuf;
- } else {
- kbuf = ERR_PTR(-ENOBUFS);
- }
-
- io_ring_submit_unlock(req->ctx, needs_lock);
- return kbuf;
-}
-
-static void __user *io_rw_buffer_select(struct io_kiocb *req, size_t *len,
- unsigned int issue_flags)
-{
- struct io_buffer *kbuf;
- u16 bgid;
-
- bgid = req->buf_index;
- kbuf = io_buffer_select(req, len, bgid, issue_flags);
- if (IS_ERR(kbuf))
- return kbuf;
- return u64_to_user_ptr(kbuf->addr);
-}
-
-#ifdef CONFIG_COMPAT
-static ssize_t io_compat_import(struct io_kiocb *req, struct iovec *iov,
- unsigned int issue_flags)
-{
- struct compat_iovec __user *uiov;
- compat_ssize_t clen;
- void __user *buf;
- ssize_t len;
-
- uiov = u64_to_user_ptr(req->rw.addr);
- if (!access_ok(uiov, sizeof(*uiov)))
- return -EFAULT;
- if (__get_user(clen, &uiov->iov_len))
- return -EFAULT;
- if (clen < 0)
- return -EINVAL;
-
- len = clen;
- buf = io_rw_buffer_select(req, &len, issue_flags);
- if (IS_ERR(buf))
- return PTR_ERR(buf);
- iov[0].iov_base = buf;
- iov[0].iov_len = (compat_size_t) len;
- return 0;
-}
-#endif
-
-static ssize_t __io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
- unsigned int issue_flags)
-{
- struct iovec __user *uiov = u64_to_user_ptr(req->rw.addr);
- void __user *buf;
- ssize_t len;
-
- if (copy_from_user(iov, uiov, sizeof(*uiov)))
- return -EFAULT;
-
- len = iov[0].iov_len;
- if (len < 0)
- return -EINVAL;
- buf = io_rw_buffer_select(req, &len, issue_flags);
- if (IS_ERR(buf))
- return PTR_ERR(buf);
- iov[0].iov_base = buf;
- iov[0].iov_len = len;
- return 0;
-}
-
-static ssize_t io_iov_buffer_select(struct io_kiocb *req, struct iovec *iov,
- unsigned int issue_flags)
-{
- if (req->flags & REQ_F_BUFFER_SELECTED) {
- struct io_buffer *kbuf = req->kbuf;
-
- iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
- iov[0].iov_len = kbuf->len;
- return 0;
- }
- if (req->rw.len != 1)
- return -EINVAL;
-
-#ifdef CONFIG_COMPAT
- if (req->ctx->compat)
- return io_compat_import(req, iov, issue_flags);
-#endif
-
- return __io_iov_buffer_select(req, iov, issue_flags);
-}
-
-static struct iovec *__io_import_iovec(int rw, struct io_kiocb *req,
- struct io_rw_state *s,
- unsigned int issue_flags)
-{
- struct iov_iter *iter = &s->iter;
- u8 opcode = req->opcode;
- struct iovec *iovec;
- void __user *buf;
- size_t sqe_len;
- ssize_t ret;
-
- BUILD_BUG_ON(ERR_PTR(0) != NULL);
-
- if (opcode == IORING_OP_READ_FIXED || opcode == IORING_OP_WRITE_FIXED)
- return ERR_PTR(io_import_fixed(req, rw, iter));
-
- /* buffer index only valid with fixed read/write, or buffer select */
- if (unlikely(req->buf_index && !(req->flags & REQ_F_BUFFER_SELECT)))
- return ERR_PTR(-EINVAL);
-
- buf = u64_to_user_ptr(req->rw.addr);
- sqe_len = req->rw.len;
-
- if (opcode == IORING_OP_READ || opcode == IORING_OP_WRITE) {
- if (req->flags & REQ_F_BUFFER_SELECT) {
- buf = io_rw_buffer_select(req, &sqe_len, issue_flags);
- if (IS_ERR(buf))
- return ERR_CAST(buf);
- req->rw.len = sqe_len;
- }
-
- ret = import_single_range(rw, buf, sqe_len, s->fast_iov, iter);
- return ERR_PTR(ret);
- }
-
- iovec = s->fast_iov;
- if (req->flags & REQ_F_BUFFER_SELECT) {
- ret = io_iov_buffer_select(req, iovec, issue_flags);
- if (!ret)
- iov_iter_init(iter, rw, iovec, 1, iovec->iov_len);
- return ERR_PTR(ret);
- }
-
- ret = __import_iovec(rw, buf, sqe_len, UIO_FASTIOV, &iovec, iter,
- req->ctx->compat);
- if (unlikely(ret < 0))
- return ERR_PTR(ret);
- return iovec;
-}
-
-static inline int io_import_iovec(int rw, struct io_kiocb *req,
- struct iovec **iovec, struct io_rw_state *s,
- unsigned int issue_flags)
-{
- *iovec = __io_import_iovec(rw, req, s, issue_flags);
- if (unlikely(IS_ERR(*iovec)))
- return PTR_ERR(*iovec);
-
- iov_iter_save_state(&s->iter, &s->iter_state);
- return 0;
-}
-
-static inline loff_t *io_kiocb_ppos(struct kiocb *kiocb)
-{
- return (kiocb->ki_filp->f_mode & FMODE_STREAM) ? NULL : &kiocb->ki_pos;
-}
-
-/*
- * For files that don't have ->read_iter() and ->write_iter(), handle them
- * by looping over ->read() or ->write() manually.
- */
-static ssize_t loop_rw_iter(int rw, struct io_kiocb *req, struct iov_iter *iter)
-{
- struct kiocb *kiocb = &req->rw.kiocb;
- struct file *file = req->file;
- ssize_t ret = 0;
-
- /*
- * Don't support polled IO through this interface, and we can't
- * support non-blocking either. For the latter, this just causes
- * the kiocb to be handled from an async context.
- */
- if (kiocb->ki_flags & IOCB_HIPRI)
- return -EOPNOTSUPP;
- if ((kiocb->ki_flags & IOCB_NOWAIT) &&
- !(kiocb->ki_filp->f_flags & O_NONBLOCK))
- return -EAGAIN;
-
- while (iov_iter_count(iter)) {
- struct iovec iovec;
- ssize_t nr;
-
- if (!iov_iter_is_bvec(iter)) {
- iovec = iov_iter_iovec(iter);
- } else {
- iovec.iov_base = u64_to_user_ptr(req->rw.addr);
- iovec.iov_len = req->rw.len;
- }
-
- if (rw == READ) {
- nr = file->f_op->read(file, iovec.iov_base,
- iovec.iov_len, io_kiocb_ppos(kiocb));
- } else {
- nr = file->f_op->write(file, iovec.iov_base,
- iovec.iov_len, io_kiocb_ppos(kiocb));
- }
-
- if (nr < 0) {
- if (!ret)
- ret = nr;
- break;
- }
- if (!iov_iter_is_bvec(iter)) {
- iov_iter_advance(iter, nr);
- } else {
- req->rw.len -= nr;
- req->rw.addr += nr;
- }
- ret += nr;
- if (nr != iovec.iov_len)
- break;
- }
-
- return ret;
-}
-
-static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
- const struct iovec *fast_iov, struct iov_iter *iter)
-{
- struct io_async_rw *rw = req->async_data;
-
- memcpy(&rw->s.iter, iter, sizeof(*iter));
- rw->free_iovec = iovec;
- rw->bytes_done = 0;
- /* can only be fixed buffers, no need to do anything */
- if (iov_iter_is_bvec(iter))
- return;
- if (!iovec) {
- unsigned iov_off = 0;
-
- rw->s.iter.iov = rw->s.fast_iov;
- if (iter->iov != fast_iov) {
- iov_off = iter->iov - fast_iov;
- rw->s.iter.iov += iov_off;
- }
- if (rw->s.fast_iov != fast_iov)
- memcpy(rw->s.fast_iov + iov_off, fast_iov + iov_off,
- sizeof(struct iovec) * iter->nr_segs);
- } else {
- req->flags |= REQ_F_NEED_CLEANUP;
- }
-}
-
-static inline bool io_alloc_async_data(struct io_kiocb *req)
-{
- WARN_ON_ONCE(!io_op_defs[req->opcode].async_size);
- req->async_data = kmalloc(io_op_defs[req->opcode].async_size, GFP_KERNEL);
- if (req->async_data) {
- req->flags |= REQ_F_ASYNC_DATA;
- return false;
- }
- return true;
-}
-
-static int io_setup_async_rw(struct io_kiocb *req, const struct iovec *iovec,
- struct io_rw_state *s, bool force)
-{
- if (!force && !io_op_defs[req->opcode].needs_async_setup)
- return 0;
- if (!req_has_async_data(req)) {
- struct io_async_rw *iorw;
-
- if (io_alloc_async_data(req)) {
- kfree(iovec);
- return -ENOMEM;
- }
-
- io_req_map_rw(req, iovec, s->fast_iov, &s->iter);
- iorw = req->async_data;
- /* we've copied and mapped the iter, ensure state is saved */
- iov_iter_save_state(&iorw->s.iter, &iorw->s.iter_state);
- }
- return 0;
-}
-
-static inline int io_rw_prep_async(struct io_kiocb *req, int rw)
-{
- struct io_async_rw *iorw = req->async_data;
- struct iovec *iov;
- int ret;
-
- /* submission path, ->uring_lock should already be taken */
- ret = io_import_iovec(rw, req, &iov, &iorw->s, 0);
- if (unlikely(ret < 0))
- return ret;
-
- iorw->bytes_done = 0;
- iorw->free_iovec = iov;
- if (iov)
- req->flags |= REQ_F_NEED_CLEANUP;
- return 0;
-}
-
-static int io_read_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- if (unlikely(!(req->file->f_mode & FMODE_READ)))
- return -EBADF;
- return io_prep_rw(req, sqe);
-}
-
-/*
- * This is our waitqueue callback handler, registered through __folio_lock_async()
- * when we initially tried to do the IO with the iocb armed our waitqueue.
- * This gets called when the page is unlocked, and we generally expect that to
- * happen when the page IO is completed and the page is now uptodate. This will
- * queue a task_work based retry of the operation, attempting to copy the data
- * again. If the latter fails because the page was NOT uptodate, then we will
- * do a thread based blocking retry of the operation. That's the unexpected
- * slow path.
- */
-static int io_async_buf_func(struct wait_queue_entry *wait, unsigned mode,
- int sync, void *arg)
-{
- struct wait_page_queue *wpq;
- struct io_kiocb *req = wait->private;
- struct wait_page_key *key = arg;
-
- wpq = container_of(wait, struct wait_page_queue, wait);
-
- if (!wake_page_match(wpq, key))
- return 0;
-
- req->rw.kiocb.ki_flags &= ~IOCB_WAITQ;
- list_del_init(&wait->entry);
- io_req_task_queue(req);
- return 1;
-}
-
-/*
- * This controls whether a given IO request should be armed for async page
- * based retry. If we return false here, the request is handed to the async
- * worker threads for retry. If we're doing buffered reads on a regular file,
- * we prepare a private wait_page_queue entry and retry the operation. This
- * will either succeed because the page is now uptodate and unlocked, or it
- * will register a callback when the page is unlocked at IO completion. Through
- * that callback, io_uring uses task_work to setup a retry of the operation.
- * That retry will attempt the buffered read again. The retry will generally
- * succeed, or in rare cases where it fails, we then fall back to using the
- * async worker threads for a blocking retry.
- */
-static bool io_rw_should_retry(struct io_kiocb *req)
-{
- struct io_async_rw *rw = req->async_data;
- struct wait_page_queue *wait = &rw->wpq;
- struct kiocb *kiocb = &req->rw.kiocb;
-
- /* never retry for NOWAIT, we just complete with -EAGAIN */
- if (req->flags & REQ_F_NOWAIT)
- return false;
-
- /* Only for buffered IO */
- if (kiocb->ki_flags & (IOCB_DIRECT | IOCB_HIPRI))
- return false;
-
- /*
- * just use poll if we can, and don't attempt if the fs doesn't
- * support callback based unlocks
- */
- if (file_can_poll(req->file) || !(req->file->f_mode & FMODE_BUF_RASYNC))
- return false;
-
- wait->wait.func = io_async_buf_func;
- wait->wait.private = req;
- wait->wait.flags = 0;
- INIT_LIST_HEAD(&wait->wait.entry);
- kiocb->ki_flags |= IOCB_WAITQ;
- kiocb->ki_flags &= ~IOCB_NOWAIT;
- kiocb->ki_waitq = wait;
- return true;
-}
-
-static inline int io_iter_do_read(struct io_kiocb *req, struct iov_iter *iter)
-{
- if (likely(req->file->f_op->read_iter))
- return call_read_iter(req->file, &req->rw.kiocb, iter);
- else if (req->file->f_op->read)
- return loop_rw_iter(READ, req, iter);
- else
- return -EINVAL;
-}
-
-static bool need_read_all(struct io_kiocb *req)
-{
- return req->flags & REQ_F_ISREG ||
- S_ISBLK(file_inode(req->file)->i_mode);
-}
-
-static int io_read(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_rw_state __s, *s = &__s;
- struct iovec *iovec;
- struct kiocb *kiocb = &req->rw.kiocb;
- bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
- struct io_async_rw *rw;
- ssize_t ret, ret2;
-
- if (!req_has_async_data(req)) {
- ret = io_import_iovec(READ, req, &iovec, s, issue_flags);
- if (unlikely(ret < 0))
- return ret;
- } else {
- rw = req->async_data;
- s = &rw->s;
- /*
- * We come here from an earlier attempt, restore our state to
- * match in case it doesn't. It's cheap enough that we don't
- * need to make this conditional.
- */
- iov_iter_restore(&s->iter, &s->iter_state);
- iovec = NULL;
- }
- req->result = iov_iter_count(&s->iter);
-
- if (force_nonblock) {
- /* If the file doesn't support async, just async punt */
- if (unlikely(!io_file_supports_nowait(req))) {
- ret = io_setup_async_rw(req, iovec, s, true);
- return ret ?: -EAGAIN;
- }
- kiocb->ki_flags |= IOCB_NOWAIT;
- } else {
- /* Ensure we clear previously set non-block flag */
- kiocb->ki_flags &= ~IOCB_NOWAIT;
- }
-
- ret = rw_verify_area(READ, req->file, io_kiocb_ppos(kiocb), req->result);
- if (unlikely(ret)) {
- kfree(iovec);
- return ret;
- }
-
- ret = io_iter_do_read(req, &s->iter);
-
- if (ret == -EAGAIN || (req->flags & REQ_F_REISSUE)) {
- req->flags &= ~REQ_F_REISSUE;
- /* IOPOLL retry should happen for io-wq threads */
- if (!force_nonblock && !(req->ctx->flags & IORING_SETUP_IOPOLL))
- goto done;
- /* no retry on NONBLOCK nor RWF_NOWAIT */
- if (req->flags & REQ_F_NOWAIT)
- goto done;
- ret = 0;
- } else if (ret == -EIOCBQUEUED) {
- goto out_free;
- } else if (ret == req->result || ret <= 0 || !force_nonblock ||
- (req->flags & REQ_F_NOWAIT) || !need_read_all(req)) {
- /* read all, failed, already did sync or don't want to retry */
- goto done;
- }
-
- /*
- * Don't depend on the iter state matching what was consumed, or being
- * untouched in case of error. Restore it and we'll advance it
- * manually if we need to.
- */
- iov_iter_restore(&s->iter, &s->iter_state);
-
- ret2 = io_setup_async_rw(req, iovec, s, true);
- if (ret2)
- return ret2;
-
- iovec = NULL;
- rw = req->async_data;
- s = &rw->s;
- /*
- * Now use our persistent iterator and state, if we aren't already.
- * We've restored and mapped the iter to match.
- */
-
- do {
- /*
- * We end up here because of a partial read, either from
- * above or inside this loop. Advance the iter by the bytes
- * that were consumed.
- */
- iov_iter_advance(&s->iter, ret);
- if (!iov_iter_count(&s->iter))
- break;
- rw->bytes_done += ret;
- iov_iter_save_state(&s->iter, &s->iter_state);
-
- /* if we can retry, do so with the callbacks armed */
- if (!io_rw_should_retry(req)) {
- kiocb->ki_flags &= ~IOCB_WAITQ;
- return -EAGAIN;
- }
-
- /*
- * Now retry read with the IOCB_WAITQ parts set in the iocb. If
- * we get -EIOCBQUEUED, then we'll get a notification when the
- * desired page gets unlocked. We can also get a partial read
- * here, and if we do, then just retry at the new offset.
- */
- ret = io_iter_do_read(req, &s->iter);
- if (ret == -EIOCBQUEUED)
- return 0;
- /* we got some bytes, but not all. retry. */
- kiocb->ki_flags &= ~IOCB_WAITQ;
- iov_iter_restore(&s->iter, &s->iter_state);
- } while (ret > 0);
-done:
- kiocb_done(kiocb, ret, issue_flags);
-out_free:
- /* it's faster to check here then delegate to kfree */
- if (iovec)
- kfree(iovec);
- return 0;
-}
-
-static int io_write_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- if (unlikely(!(req->file->f_mode & FMODE_WRITE)))
- return -EBADF;
- req->rw.kiocb.ki_hint = ki_hint_validate(file_write_hint(req->file));
- return io_prep_rw(req, sqe);
-}
-
-static int io_write(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_rw_state __s, *s = &__s;
- struct iovec *iovec;
- struct kiocb *kiocb = &req->rw.kiocb;
- bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
- ssize_t ret, ret2;
-
- if (!req_has_async_data(req)) {
- ret = io_import_iovec(WRITE, req, &iovec, s, issue_flags);
- if (unlikely(ret < 0))
- return ret;
- } else {
- struct io_async_rw *rw = req->async_data;
-
- s = &rw->s;
- iov_iter_restore(&s->iter, &s->iter_state);
- iovec = NULL;
- }
- req->result = iov_iter_count(&s->iter);
-
- if (force_nonblock) {
- /* If the file doesn't support async, just async punt */
- if (unlikely(!io_file_supports_nowait(req)))
- goto copy_iov;
-
- /* file path doesn't support NOWAIT for non-direct_IO */
- if (force_nonblock && !(kiocb->ki_flags & IOCB_DIRECT) &&
- (req->flags & REQ_F_ISREG))
- goto copy_iov;
-
- kiocb->ki_flags |= IOCB_NOWAIT;
- } else {
- /* Ensure we clear previously set non-block flag */
- kiocb->ki_flags &= ~IOCB_NOWAIT;
- }
-
- ret = rw_verify_area(WRITE, req->file, io_kiocb_ppos(kiocb), req->result);
- if (unlikely(ret))
- goto out_free;
-
- /*
- * Open-code file_start_write here to grab freeze protection,
- * which will be released by another thread in
- * io_complete_rw(). Fool lockdep by telling it the lock got
- * released so that it doesn't complain about the held lock when
- * we return to userspace.
- */
- if (req->flags & REQ_F_ISREG) {
- sb_start_write(file_inode(req->file)->i_sb);
- __sb_writers_release(file_inode(req->file)->i_sb,
- SB_FREEZE_WRITE);
- }
- kiocb->ki_flags |= IOCB_WRITE;
-
- if (likely(req->file->f_op->write_iter))
- ret2 = call_write_iter(req->file, kiocb, &s->iter);
- else if (req->file->f_op->write)
- ret2 = loop_rw_iter(WRITE, req, &s->iter);
- else
- ret2 = -EINVAL;
-
- if (req->flags & REQ_F_REISSUE) {
- req->flags &= ~REQ_F_REISSUE;
- ret2 = -EAGAIN;
- }
-
- /*
- * Raw bdev writes will return -EOPNOTSUPP for IOCB_NOWAIT. Just
- * retry them without IOCB_NOWAIT.
- */
- if (ret2 == -EOPNOTSUPP && (kiocb->ki_flags & IOCB_NOWAIT))
- ret2 = -EAGAIN;
- /* no retry on NONBLOCK nor RWF_NOWAIT */
- if (ret2 == -EAGAIN && (req->flags & REQ_F_NOWAIT))
- goto done;
- if (!force_nonblock || ret2 != -EAGAIN) {
- /* IOPOLL retry should happen for io-wq threads */
- if (ret2 == -EAGAIN && (req->ctx->flags & IORING_SETUP_IOPOLL))
- goto copy_iov;
-done:
- kiocb_done(kiocb, ret2, issue_flags);
- } else {
-copy_iov:
- iov_iter_restore(&s->iter, &s->iter_state);
- ret = io_setup_async_rw(req, iovec, s, false);
- return ret ?: -EAGAIN;
- }
-out_free:
- /* it's reportedly faster than delegating the null check to kfree() */
- if (iovec)
- kfree(iovec);
- return ret;
-}
-
-static int io_renameat_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- struct io_rename *ren = &req->rename;
- const char __user *oldf, *newf;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
- return -EINVAL;
- if (unlikely(req->flags & REQ_F_FIXED_FILE))
- return -EBADF;
-
- ren->old_dfd = READ_ONCE(sqe->fd);
- oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
- newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
- ren->new_dfd = READ_ONCE(sqe->len);
- ren->flags = READ_ONCE(sqe->rename_flags);
-
- ren->oldpath = getname(oldf);
- if (IS_ERR(ren->oldpath))
- return PTR_ERR(ren->oldpath);
-
- ren->newpath = getname(newf);
- if (IS_ERR(ren->newpath)) {
- putname(ren->oldpath);
- return PTR_ERR(ren->newpath);
- }
-
- req->flags |= REQ_F_NEED_CLEANUP;
- return 0;
-}
-
-static int io_renameat(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_rename *ren = &req->rename;
- int ret;
-
- if (issue_flags & IO_URING_F_NONBLOCK)
- return -EAGAIN;
-
- ret = do_renameat2(ren->old_dfd, ren->oldpath, ren->new_dfd,
- ren->newpath, ren->flags);
-
- req->flags &= ~REQ_F_NEED_CLEANUP;
- if (ret < 0)
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
-}
-
-static int io_unlinkat_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- struct io_unlink *un = &req->unlink;
- const char __user *fname;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (sqe->ioprio || sqe->off || sqe->len || sqe->buf_index ||
- sqe->splice_fd_in)
- return -EINVAL;
- if (unlikely(req->flags & REQ_F_FIXED_FILE))
- return -EBADF;
-
- un->dfd = READ_ONCE(sqe->fd);
-
- un->flags = READ_ONCE(sqe->unlink_flags);
- if (un->flags & ~AT_REMOVEDIR)
- return -EINVAL;
-
- fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
- un->filename = getname(fname);
- if (IS_ERR(un->filename))
- return PTR_ERR(un->filename);
-
- req->flags |= REQ_F_NEED_CLEANUP;
- return 0;
-}
-
-static int io_unlinkat(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_unlink *un = &req->unlink;
- int ret;
-
- if (issue_flags & IO_URING_F_NONBLOCK)
- return -EAGAIN;
-
- if (un->flags & AT_REMOVEDIR)
- ret = do_rmdir(un->dfd, un->filename);
- else
- ret = do_unlinkat(un->dfd, un->filename);
-
- req->flags &= ~REQ_F_NEED_CLEANUP;
- if (ret < 0)
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
-}
-
-static int io_mkdirat_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- struct io_mkdir *mkd = &req->mkdir;
- const char __user *fname;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (sqe->ioprio || sqe->off || sqe->rw_flags || sqe->buf_index ||
- sqe->splice_fd_in)
- return -EINVAL;
- if (unlikely(req->flags & REQ_F_FIXED_FILE))
- return -EBADF;
-
- mkd->dfd = READ_ONCE(sqe->fd);
- mkd->mode = READ_ONCE(sqe->len);
-
- fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
- mkd->filename = getname(fname);
- if (IS_ERR(mkd->filename))
- return PTR_ERR(mkd->filename);
-
- req->flags |= REQ_F_NEED_CLEANUP;
- return 0;
-}
-
-static int io_mkdirat(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_mkdir *mkd = &req->mkdir;
- int ret;
-
- if (issue_flags & IO_URING_F_NONBLOCK)
- return -EAGAIN;
-
- ret = do_mkdirat(mkd->dfd, mkd->filename, mkd->mode);
-
- req->flags &= ~REQ_F_NEED_CLEANUP;
- if (ret < 0)
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
-}
-
-static int io_symlinkat_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- struct io_symlink *sl = &req->symlink;
- const char __user *oldpath, *newpath;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (sqe->ioprio || sqe->len || sqe->rw_flags || sqe->buf_index ||
- sqe->splice_fd_in)
- return -EINVAL;
- if (unlikely(req->flags & REQ_F_FIXED_FILE))
- return -EBADF;
-
- sl->new_dfd = READ_ONCE(sqe->fd);
- oldpath = u64_to_user_ptr(READ_ONCE(sqe->addr));
- newpath = u64_to_user_ptr(READ_ONCE(sqe->addr2));
-
- sl->oldpath = getname(oldpath);
- if (IS_ERR(sl->oldpath))
- return PTR_ERR(sl->oldpath);
-
- sl->newpath = getname(newpath);
- if (IS_ERR(sl->newpath)) {
- putname(sl->oldpath);
- return PTR_ERR(sl->newpath);
- }
-
- req->flags |= REQ_F_NEED_CLEANUP;
- return 0;
-}
-
-static int io_symlinkat(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_symlink *sl = &req->symlink;
- int ret;
-
- if (issue_flags & IO_URING_F_NONBLOCK)
- return -EAGAIN;
-
- ret = do_symlinkat(sl->oldpath, sl->new_dfd, sl->newpath);
-
- req->flags &= ~REQ_F_NEED_CLEANUP;
- if (ret < 0)
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
-}
-
-static int io_linkat_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- struct io_hardlink *lnk = &req->hardlink;
- const char __user *oldf, *newf;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (sqe->ioprio || sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
- return -EINVAL;
- if (unlikely(req->flags & REQ_F_FIXED_FILE))
- return -EBADF;
-
- lnk->old_dfd = READ_ONCE(sqe->fd);
- lnk->new_dfd = READ_ONCE(sqe->len);
- oldf = u64_to_user_ptr(READ_ONCE(sqe->addr));
- newf = u64_to_user_ptr(READ_ONCE(sqe->addr2));
- lnk->flags = READ_ONCE(sqe->hardlink_flags);
-
- lnk->oldpath = getname(oldf);
- if (IS_ERR(lnk->oldpath))
- return PTR_ERR(lnk->oldpath);
-
- lnk->newpath = getname(newf);
- if (IS_ERR(lnk->newpath)) {
- putname(lnk->oldpath);
- return PTR_ERR(lnk->newpath);
- }
-
- req->flags |= REQ_F_NEED_CLEANUP;
- return 0;
-}
-
-static int io_linkat(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_hardlink *lnk = &req->hardlink;
- int ret;
-
- if (issue_flags & IO_URING_F_NONBLOCK)
- return -EAGAIN;
-
- ret = do_linkat(lnk->old_dfd, lnk->oldpath, lnk->new_dfd,
- lnk->newpath, lnk->flags);
-
- req->flags &= ~REQ_F_NEED_CLEANUP;
- if (ret < 0)
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
-}
-
-static int io_shutdown_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
-#if defined(CONFIG_NET)
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (unlikely(sqe->ioprio || sqe->off || sqe->addr || sqe->rw_flags ||
- sqe->buf_index || sqe->splice_fd_in))
- return -EINVAL;
-
- req->shutdown.how = READ_ONCE(sqe->len);
- return 0;
-#else
- return -EOPNOTSUPP;
-#endif
-}
-
-static int io_shutdown(struct io_kiocb *req, unsigned int issue_flags)
-{
-#if defined(CONFIG_NET)
- struct socket *sock;
- int ret;
-
- if (issue_flags & IO_URING_F_NONBLOCK)
- return -EAGAIN;
-
- sock = sock_from_file(req->file);
- if (unlikely(!sock))
- return -ENOTSOCK;
-
- ret = __sys_shutdown_sock(sock, req->shutdown.how);
- if (ret < 0)
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
-#else
- return -EOPNOTSUPP;
-#endif
-}
-
-static int __io_splice_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- struct io_splice *sp = &req->splice;
- unsigned int valid_flags = SPLICE_F_FD_IN_FIXED | SPLICE_F_ALL;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
-
- sp->file_in = NULL;
- sp->len = READ_ONCE(sqe->len);
- sp->flags = READ_ONCE(sqe->splice_flags);
-
- if (unlikely(sp->flags & ~valid_flags))
- return -EINVAL;
-
- sp->file_in = io_file_get(req->ctx, req, READ_ONCE(sqe->splice_fd_in),
- (sp->flags & SPLICE_F_FD_IN_FIXED));
- if (!sp->file_in)
- return -EBADF;
- req->flags |= REQ_F_NEED_CLEANUP;
- return 0;
-}
-
-static int io_tee_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- if (READ_ONCE(sqe->splice_off_in) || READ_ONCE(sqe->off))
- return -EINVAL;
- return __io_splice_prep(req, sqe);
-}
-
-static int io_tee(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_splice *sp = &req->splice;
- struct file *in = sp->file_in;
- struct file *out = sp->file_out;
- unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
- long ret = 0;
-
- if (issue_flags & IO_URING_F_NONBLOCK)
- return -EAGAIN;
- if (sp->len)
- ret = do_tee(in, out, sp->len, flags);
-
- if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
- io_put_file(in);
- req->flags &= ~REQ_F_NEED_CLEANUP;
-
- if (ret != sp->len)
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
-}
-
-static int io_splice_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- struct io_splice *sp = &req->splice;
-
- sp->off_in = READ_ONCE(sqe->splice_off_in);
- sp->off_out = READ_ONCE(sqe->off);
- return __io_splice_prep(req, sqe);
-}
-
-static int io_splice(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_splice *sp = &req->splice;
- struct file *in = sp->file_in;
- struct file *out = sp->file_out;
- unsigned int flags = sp->flags & ~SPLICE_F_FD_IN_FIXED;
- loff_t *poff_in, *poff_out;
- long ret = 0;
-
- if (issue_flags & IO_URING_F_NONBLOCK)
- return -EAGAIN;
-
- poff_in = (sp->off_in == -1) ? NULL : &sp->off_in;
- poff_out = (sp->off_out == -1) ? NULL : &sp->off_out;
-
- if (sp->len)
- ret = do_splice(in, poff_in, out, poff_out, sp->len, flags);
-
- if (!(sp->flags & SPLICE_F_FD_IN_FIXED))
- io_put_file(in);
- req->flags &= ~REQ_F_NEED_CLEANUP;
-
- if (ret != sp->len)
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
-}
-
-/*
- * IORING_OP_NOP just posts a completion event, nothing else.
- */
-static int io_nop(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_ring_ctx *ctx = req->ctx;
-
- if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
-
- __io_req_complete(req, issue_flags, 0, 0);
- return 0;
-}
-
-static int io_fsync_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- struct io_ring_ctx *ctx = req->ctx;
-
- if (!req->file)
- return -EBADF;
-
- if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index ||
- sqe->splice_fd_in))
- return -EINVAL;
-
- req->sync.flags = READ_ONCE(sqe->fsync_flags);
- if (unlikely(req->sync.flags & ~IORING_FSYNC_DATASYNC))
- return -EINVAL;
-
- req->sync.off = READ_ONCE(sqe->off);
- req->sync.len = READ_ONCE(sqe->len);
- return 0;
-}
-
-static int io_fsync(struct io_kiocb *req, unsigned int issue_flags)
-{
- loff_t end = req->sync.off + req->sync.len;
- int ret;
-
- /* fsync always requires a blocking context */
- if (issue_flags & IO_URING_F_NONBLOCK)
- return -EAGAIN;
-
- ret = vfs_fsync_range(req->file, req->sync.off,
- end > 0 ? end : LLONG_MAX,
- req->sync.flags & IORING_FSYNC_DATASYNC);
- if (ret < 0)
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
-}
-
-static int io_fallocate_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- if (sqe->ioprio || sqe->buf_index || sqe->rw_flags ||
- sqe->splice_fd_in)
- return -EINVAL;
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
-
- req->sync.off = READ_ONCE(sqe->off);
- req->sync.len = READ_ONCE(sqe->addr);
- req->sync.mode = READ_ONCE(sqe->len);
- return 0;
-}
-
-static int io_fallocate(struct io_kiocb *req, unsigned int issue_flags)
-{
- int ret;
-
- /* fallocate always requiring blocking context */
- if (issue_flags & IO_URING_F_NONBLOCK)
- return -EAGAIN;
- ret = vfs_fallocate(req->file, req->sync.mode, req->sync.off,
- req->sync.len);
- if (ret < 0)
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
-}
-
-static int __io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- const char __user *fname;
- int ret;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (unlikely(sqe->ioprio || sqe->buf_index))
- return -EINVAL;
- if (unlikely(req->flags & REQ_F_FIXED_FILE))
- return -EBADF;
-
- /* open.how should be already initialised */
- if (!(req->open.how.flags & O_PATH) && force_o_largefile())
- req->open.how.flags |= O_LARGEFILE;
-
- req->open.dfd = READ_ONCE(sqe->fd);
- fname = u64_to_user_ptr(READ_ONCE(sqe->addr));
- req->open.filename = getname(fname);
- if (IS_ERR(req->open.filename)) {
- ret = PTR_ERR(req->open.filename);
- req->open.filename = NULL;
- return ret;
- }
-
- req->open.file_slot = READ_ONCE(sqe->file_index);
- if (req->open.file_slot && (req->open.how.flags & O_CLOEXEC))
- return -EINVAL;
-
- req->open.nofile = rlimit(RLIMIT_NOFILE);
- req->flags |= REQ_F_NEED_CLEANUP;
- return 0;
-}
-
-static int io_openat_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- u64 mode = READ_ONCE(sqe->len);
- u64 flags = READ_ONCE(sqe->open_flags);
-
- req->open.how = build_open_how(flags, mode);
- return __io_openat_prep(req, sqe);
-}
-
-static int io_openat2_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- struct open_how __user *how;
- size_t len;
- int ret;
-
- how = u64_to_user_ptr(READ_ONCE(sqe->addr2));
- len = READ_ONCE(sqe->len);
- if (len < OPEN_HOW_SIZE_VER0)
- return -EINVAL;
-
- ret = copy_struct_from_user(&req->open.how, sizeof(req->open.how), how,
- len);
- if (ret)
- return ret;
-
- return __io_openat_prep(req, sqe);
-}
-
-static int io_openat2(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct open_flags op;
- struct file *file;
- bool resolve_nonblock, nonblock_set;
- bool fixed = !!req->open.file_slot;
- int ret;
-
- ret = build_open_flags(&req->open.how, &op);
- if (ret)
- goto err;
- nonblock_set = op.open_flag & O_NONBLOCK;
- resolve_nonblock = req->open.how.resolve & RESOLVE_CACHED;
- if (issue_flags & IO_URING_F_NONBLOCK) {
- /*
- * Don't bother trying for O_TRUNC, O_CREAT, or O_TMPFILE open,
- * it'll always -EAGAIN
- */
- if (req->open.how.flags & (O_TRUNC | O_CREAT | O_TMPFILE))
- return -EAGAIN;
- op.lookup_flags |= LOOKUP_CACHED;
- op.open_flag |= O_NONBLOCK;
- }
-
- if (!fixed) {
- ret = __get_unused_fd_flags(req->open.how.flags, req->open.nofile);
- if (ret < 0)
- goto err;
- }
-
- file = do_filp_open(req->open.dfd, req->open.filename, &op);
- if (IS_ERR(file)) {
- /*
- * We could hang on to this 'fd' on retrying, but seems like
- * marginal gain for something that is now known to be a slower
- * path. So just put it, and we'll get a new one when we retry.
- */
- if (!fixed)
- put_unused_fd(ret);
-
- ret = PTR_ERR(file);
- /* only retry if RESOLVE_CACHED wasn't already set by application */
- if (ret == -EAGAIN &&
- (!resolve_nonblock && (issue_flags & IO_URING_F_NONBLOCK)))
- return -EAGAIN;
- goto err;
- }
-
- if ((issue_flags & IO_URING_F_NONBLOCK) && !nonblock_set)
- file->f_flags &= ~O_NONBLOCK;
- fsnotify_open(file);
-
- if (!fixed)
- fd_install(ret, file);
- else
- ret = io_install_fixed_file(req, file, issue_flags,
- req->open.file_slot - 1);
-err:
- putname(req->open.filename);
- req->flags &= ~REQ_F_NEED_CLEANUP;
- if (ret < 0)
- req_set_fail(req);
- __io_req_complete(req, issue_flags, ret, 0);
- return 0;
-}
-
-static int io_openat(struct io_kiocb *req, unsigned int issue_flags)
-{
- return io_openat2(req, issue_flags);
-}
-
-static int io_remove_buffers_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- struct io_provide_buf *p = &req->pbuf;
- u64 tmp;
-
- if (sqe->ioprio || sqe->rw_flags || sqe->addr || sqe->len || sqe->off ||
- sqe->splice_fd_in)
- return -EINVAL;
-
- tmp = READ_ONCE(sqe->fd);
- if (!tmp || tmp > USHRT_MAX)
- return -EINVAL;
-
- memset(p, 0, sizeof(*p));
- p->nbufs = tmp;
- p->bgid = READ_ONCE(sqe->buf_group);
- return 0;
-}
-
-static int __io_remove_buffers(struct io_ring_ctx *ctx, struct io_buffer *buf,
- int bgid, unsigned nbufs)
-{
- unsigned i = 0;
-
- /* shouldn't happen */
- if (!nbufs)
- return 0;
-
- /* the head kbuf is the list itself */
- while (!list_empty(&buf->list)) {
- struct io_buffer *nxt;
-
- nxt = list_first_entry(&buf->list, struct io_buffer, list);
- list_del(&nxt->list);
- kfree(nxt);
- if (++i == nbufs)
- return i;
- cond_resched();
- }
- i++;
- kfree(buf);
- xa_erase(&ctx->io_buffers, bgid);
-
- return i;
-}
-
-static int io_remove_buffers(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_provide_buf *p = &req->pbuf;
- struct io_ring_ctx *ctx = req->ctx;
- struct io_buffer *head;
- int ret = 0;
- bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
-
- io_ring_submit_lock(ctx, needs_lock);
-
- lockdep_assert_held(&ctx->uring_lock);
-
- ret = -ENOENT;
- head = xa_load(&ctx->io_buffers, p->bgid);
- if (head)
- ret = __io_remove_buffers(ctx, head, p->bgid, p->nbufs);
- if (ret < 0)
- req_set_fail(req);
-
- /* complete before unlock, IOPOLL may need the lock */
- __io_req_complete(req, issue_flags, ret, 0);
- io_ring_submit_unlock(ctx, needs_lock);
- return 0;
-}
-
-static int io_provide_buffers_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- unsigned long size, tmp_check;
- struct io_provide_buf *p = &req->pbuf;
- u64 tmp;
-
- if (sqe->ioprio || sqe->rw_flags || sqe->splice_fd_in)
- return -EINVAL;
-
- tmp = READ_ONCE(sqe->fd);
- if (!tmp || tmp > USHRT_MAX)
- return -E2BIG;
- p->nbufs = tmp;
- p->addr = READ_ONCE(sqe->addr);
- p->len = READ_ONCE(sqe->len);
-
- if (check_mul_overflow((unsigned long)p->len, (unsigned long)p->nbufs,
- &size))
- return -EOVERFLOW;
- if (check_add_overflow((unsigned long)p->addr, size, &tmp_check))
- return -EOVERFLOW;
-
- size = (unsigned long)p->len * p->nbufs;
- if (!access_ok(u64_to_user_ptr(p->addr), size))
- return -EFAULT;
-
- p->bgid = READ_ONCE(sqe->buf_group);
- tmp = READ_ONCE(sqe->off);
- if (tmp > USHRT_MAX)
- return -E2BIG;
- p->bid = tmp;
- return 0;
-}
-
-static int io_add_buffers(struct io_provide_buf *pbuf, struct io_buffer **head)
-{
- struct io_buffer *buf;
- u64 addr = pbuf->addr;
- int i, bid = pbuf->bid;
-
- for (i = 0; i < pbuf->nbufs; i++) {
- buf = kmalloc(sizeof(*buf), GFP_KERNEL_ACCOUNT);
- if (!buf)
- break;
-
- buf->addr = addr;
- buf->len = min_t(__u32, pbuf->len, MAX_RW_COUNT);
- buf->bid = bid;
- addr += pbuf->len;
- bid++;
- if (!*head) {
- INIT_LIST_HEAD(&buf->list);
- *head = buf;
- } else {
- list_add_tail(&buf->list, &(*head)->list);
- }
- }
-
- return i ? i : -ENOMEM;
-}
-
-static int io_provide_buffers(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_provide_buf *p = &req->pbuf;
- struct io_ring_ctx *ctx = req->ctx;
- struct io_buffer *head, *list;
- int ret = 0;
- bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
-
- io_ring_submit_lock(ctx, needs_lock);
-
- lockdep_assert_held(&ctx->uring_lock);
-
- list = head = xa_load(&ctx->io_buffers, p->bgid);
-
- ret = io_add_buffers(p, &head);
- if (ret >= 0 && !list) {
- ret = xa_insert(&ctx->io_buffers, p->bgid, head, GFP_KERNEL);
- if (ret < 0)
- __io_remove_buffers(ctx, head, p->bgid, -1U);
- }
- if (ret < 0)
- req_set_fail(req);
- /* complete before unlock, IOPOLL may need the lock */
- __io_req_complete(req, issue_flags, ret, 0);
- io_ring_submit_unlock(ctx, needs_lock);
- return 0;
-}
-
-static int io_epoll_ctl_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
-#if defined(CONFIG_EPOLL)
- if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
- return -EINVAL;
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
-
- req->epoll.epfd = READ_ONCE(sqe->fd);
- req->epoll.op = READ_ONCE(sqe->len);
- req->epoll.fd = READ_ONCE(sqe->off);
-
- if (ep_op_has_event(req->epoll.op)) {
- struct epoll_event __user *ev;
-
- ev = u64_to_user_ptr(READ_ONCE(sqe->addr));
- if (copy_from_user(&req->epoll.event, ev, sizeof(*ev)))
- return -EFAULT;
- }
-
- return 0;
-#else
- return -EOPNOTSUPP;
-#endif
-}
-
-static int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
-{
-#if defined(CONFIG_EPOLL)
- struct io_epoll *ie = &req->epoll;
- int ret;
- bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
-
- ret = do_epoll_ctl(ie->epfd, ie->op, ie->fd, &ie->event, force_nonblock);
- if (force_nonblock && ret == -EAGAIN)
- return -EAGAIN;
-
- if (ret < 0)
- req_set_fail(req);
- __io_req_complete(req, issue_flags, ret, 0);
- return 0;
-#else
- return -EOPNOTSUPP;
-#endif
-}
-
-static int io_madvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
-#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
- if (sqe->ioprio || sqe->buf_index || sqe->off || sqe->splice_fd_in)
- return -EINVAL;
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
-
- req->madvise.addr = READ_ONCE(sqe->addr);
- req->madvise.len = READ_ONCE(sqe->len);
- req->madvise.advice = READ_ONCE(sqe->fadvise_advice);
- return 0;
-#else
- return -EOPNOTSUPP;
-#endif
-}
-
-static int io_madvise(struct io_kiocb *req, unsigned int issue_flags)
-{
-#if defined(CONFIG_ADVISE_SYSCALLS) && defined(CONFIG_MMU)
- struct io_madvise *ma = &req->madvise;
- int ret;
-
- if (issue_flags & IO_URING_F_NONBLOCK)
- return -EAGAIN;
-
- ret = do_madvise(current->mm, ma->addr, ma->len, ma->advice);
- if (ret < 0)
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
-#else
- return -EOPNOTSUPP;
-#endif
-}
-
-static int io_fadvise_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- if (sqe->ioprio || sqe->buf_index || sqe->addr || sqe->splice_fd_in)
- return -EINVAL;
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
-
- req->fadvise.offset = READ_ONCE(sqe->off);
- req->fadvise.len = READ_ONCE(sqe->len);
- req->fadvise.advice = READ_ONCE(sqe->fadvise_advice);
- return 0;
-}
-
-static int io_fadvise(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_fadvise *fa = &req->fadvise;
- int ret;
-
- if (issue_flags & IO_URING_F_NONBLOCK) {
- switch (fa->advice) {
- case POSIX_FADV_NORMAL:
- case POSIX_FADV_RANDOM:
- case POSIX_FADV_SEQUENTIAL:
- break;
- default:
- return -EAGAIN;
- }
- }
-
- ret = vfs_fadvise(req->file, fa->offset, fa->len, fa->advice);
- if (ret < 0)
- req_set_fail(req);
- __io_req_complete(req, issue_flags, ret, 0);
- return 0;
-}
-
-static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
- return -EINVAL;
- if (req->flags & REQ_F_FIXED_FILE)
- return -EBADF;
-
- req->statx.dfd = READ_ONCE(sqe->fd);
- req->statx.mask = READ_ONCE(sqe->len);
- req->statx.filename = u64_to_user_ptr(READ_ONCE(sqe->addr));
- req->statx.buffer = u64_to_user_ptr(READ_ONCE(sqe->addr2));
- req->statx.flags = READ_ONCE(sqe->statx_flags);
-
- return 0;
-}
-
-static int io_statx(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_statx *ctx = &req->statx;
- int ret;
-
- if (issue_flags & IO_URING_F_NONBLOCK)
- return -EAGAIN;
-
- ret = do_statx(ctx->dfd, ctx->filename, ctx->flags, ctx->mask,
- ctx->buffer);
-
- if (ret < 0)
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
-}
-
-static int io_close_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (sqe->ioprio || sqe->off || sqe->addr || sqe->len ||
- sqe->rw_flags || sqe->buf_index)
- return -EINVAL;
- if (req->flags & REQ_F_FIXED_FILE)
- return -EBADF;
-
- req->close.fd = READ_ONCE(sqe->fd);
- req->close.file_slot = READ_ONCE(sqe->file_index);
- if (req->close.file_slot && req->close.fd)
- return -EINVAL;
-
- return 0;
-}
-
-static int io_close(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct files_struct *files = current->files;
- struct io_close *close = &req->close;
- struct fdtable *fdt;
- struct file *file = NULL;
- int ret = -EBADF;
-
- if (req->close.file_slot) {
- ret = io_close_fixed(req, issue_flags);
- goto err;
- }
-
- spin_lock(&files->file_lock);
- fdt = files_fdtable(files);
- if (close->fd >= fdt->max_fds) {
- spin_unlock(&files->file_lock);
- goto err;
- }
- file = fdt->fd[close->fd];
- if (!file || file->f_op == &io_uring_fops) {
- spin_unlock(&files->file_lock);
- file = NULL;
- goto err;
- }
-
- /* if the file has a flush method, be safe and punt to async */
- if (file->f_op->flush && (issue_flags & IO_URING_F_NONBLOCK)) {
- spin_unlock(&files->file_lock);
- return -EAGAIN;
- }
-
- ret = __close_fd_get_file(close->fd, &file);
- spin_unlock(&files->file_lock);
- if (ret < 0) {
- if (ret == -ENOENT)
- ret = -EBADF;
- goto err;
- }
-
- /* No ->flush() or already async, safely close from here */
- ret = filp_close(file, current->files);
-err:
- if (ret < 0)
- req_set_fail(req);
- if (file)
- fput(file);
- __io_req_complete(req, issue_flags, ret, 0);
- return 0;
-}
-
-static int io_sfr_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- struct io_ring_ctx *ctx = req->ctx;
-
- if (unlikely(ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (unlikely(sqe->addr || sqe->ioprio || sqe->buf_index ||
- sqe->splice_fd_in))
- return -EINVAL;
-
- req->sync.off = READ_ONCE(sqe->off);
- req->sync.len = READ_ONCE(sqe->len);
- req->sync.flags = READ_ONCE(sqe->sync_range_flags);
- return 0;
-}
-
-static int io_sync_file_range(struct io_kiocb *req, unsigned int issue_flags)
-{
- int ret;
-
- /* sync_file_range always requires a blocking context */
- if (issue_flags & IO_URING_F_NONBLOCK)
- return -EAGAIN;
-
- ret = sync_file_range(req->file, req->sync.off, req->sync.len,
- req->sync.flags);
- if (ret < 0)
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
-}
-
-#if defined(CONFIG_NET)
-static int io_setup_async_msg(struct io_kiocb *req,
- struct io_async_msghdr *kmsg)
-{
- struct io_async_msghdr *async_msg = req->async_data;
-
- if (async_msg)
- return -EAGAIN;
- if (io_alloc_async_data(req)) {
- kfree(kmsg->free_iov);
- return -ENOMEM;
- }
- async_msg = req->async_data;
- req->flags |= REQ_F_NEED_CLEANUP;
- memcpy(async_msg, kmsg, sizeof(*kmsg));
- async_msg->msg.msg_name = &async_msg->addr;
- /* if were using fast_iov, set it to the new one */
- if (!async_msg->free_iov)
- async_msg->msg.msg_iter.iov = async_msg->fast_iov;
-
- return -EAGAIN;
-}
-
-static int io_sendmsg_copy_hdr(struct io_kiocb *req,
- struct io_async_msghdr *iomsg)
-{
- iomsg->msg.msg_name = &iomsg->addr;
- iomsg->free_iov = iomsg->fast_iov;
- return sendmsg_copy_msghdr(&iomsg->msg, req->sr_msg.umsg,
- req->sr_msg.msg_flags, &iomsg->free_iov);
-}
-
-static int io_sendmsg_prep_async(struct io_kiocb *req)
-{
- int ret;
-
- ret = io_sendmsg_copy_hdr(req, req->async_data);
- if (!ret)
- req->flags |= REQ_F_NEED_CLEANUP;
- return ret;
-}
-
-static int io_sendmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- struct io_sr_msg *sr = &req->sr_msg;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
-
- sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
- sr->len = READ_ONCE(sqe->len);
- sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
- if (sr->msg_flags & MSG_DONTWAIT)
- req->flags |= REQ_F_NOWAIT;
-
-#ifdef CONFIG_COMPAT
- if (req->ctx->compat)
- sr->msg_flags |= MSG_CMSG_COMPAT;
-#endif
- return 0;
-}
-
-static int io_sendmsg(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_async_msghdr iomsg, *kmsg;
- struct socket *sock;
- unsigned flags;
- int min_ret = 0;
- int ret;
-
- sock = sock_from_file(req->file);
- if (unlikely(!sock))
- return -ENOTSOCK;
-
- if (req_has_async_data(req)) {
- kmsg = req->async_data;
- } else {
- ret = io_sendmsg_copy_hdr(req, &iomsg);
- if (ret)
- return ret;
- kmsg = &iomsg;
- }
-
- flags = req->sr_msg.msg_flags;
- if (issue_flags & IO_URING_F_NONBLOCK)
- flags |= MSG_DONTWAIT;
- if (flags & MSG_WAITALL)
- min_ret = iov_iter_count(&kmsg->msg.msg_iter);
-
- ret = __sys_sendmsg_sock(sock, &kmsg->msg, flags);
- if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
- return io_setup_async_msg(req, kmsg);
- if (ret == -ERESTARTSYS)
- ret = -EINTR;
-
- /* fast path, check for non-NULL to avoid function call */
- if (kmsg->free_iov)
- kfree(kmsg->free_iov);
- req->flags &= ~REQ_F_NEED_CLEANUP;
- if (ret < min_ret)
- req_set_fail(req);
- __io_req_complete(req, issue_flags, ret, 0);
- return 0;
-}
-
-static int io_send(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_sr_msg *sr = &req->sr_msg;
- struct msghdr msg;
- struct iovec iov;
- struct socket *sock;
- unsigned flags;
- int min_ret = 0;
- int ret;
-
- sock = sock_from_file(req->file);
- if (unlikely(!sock))
- return -ENOTSOCK;
-
- ret = import_single_range(WRITE, sr->buf, sr->len, &iov, &msg.msg_iter);
- if (unlikely(ret))
- return ret;
-
- msg.msg_name = NULL;
- msg.msg_control = NULL;
- msg.msg_controllen = 0;
- msg.msg_namelen = 0;
-
- flags = req->sr_msg.msg_flags;
- if (issue_flags & IO_URING_F_NONBLOCK)
- flags |= MSG_DONTWAIT;
- if (flags & MSG_WAITALL)
- min_ret = iov_iter_count(&msg.msg_iter);
-
- msg.msg_flags = flags;
- ret = sock_sendmsg(sock, &msg);
- if ((issue_flags & IO_URING_F_NONBLOCK) && ret == -EAGAIN)
- return -EAGAIN;
- if (ret == -ERESTARTSYS)
- ret = -EINTR;
-
- if (ret < min_ret)
- req_set_fail(req);
- __io_req_complete(req, issue_flags, ret, 0);
- return 0;
-}
-
-static int __io_recvmsg_copy_hdr(struct io_kiocb *req,
- struct io_async_msghdr *iomsg)
-{
- struct io_sr_msg *sr = &req->sr_msg;
- struct iovec __user *uiov;
- size_t iov_len;
- int ret;
-
- ret = __copy_msghdr_from_user(&iomsg->msg, sr->umsg,
- &iomsg->uaddr, &uiov, &iov_len);
- if (ret)
- return ret;
-
- if (req->flags & REQ_F_BUFFER_SELECT) {
- if (iov_len > 1)
- return -EINVAL;
- if (copy_from_user(iomsg->fast_iov, uiov, sizeof(*uiov)))
- return -EFAULT;
- sr->len = iomsg->fast_iov[0].iov_len;
- iomsg->free_iov = NULL;
- } else {
- iomsg->free_iov = iomsg->fast_iov;
- ret = __import_iovec(READ, uiov, iov_len, UIO_FASTIOV,
- &iomsg->free_iov, &iomsg->msg.msg_iter,
- false);
- if (ret > 0)
- ret = 0;
- }
-
- return ret;
-}
-
-#ifdef CONFIG_COMPAT
-static int __io_compat_recvmsg_copy_hdr(struct io_kiocb *req,
- struct io_async_msghdr *iomsg)
-{
- struct io_sr_msg *sr = &req->sr_msg;
- struct compat_iovec __user *uiov;
- compat_uptr_t ptr;
- compat_size_t len;
- int ret;
-
- ret = __get_compat_msghdr(&iomsg->msg, sr->umsg_compat, &iomsg->uaddr,
- &ptr, &len);
- if (ret)
- return ret;
-
- uiov = compat_ptr(ptr);
- if (req->flags & REQ_F_BUFFER_SELECT) {
- compat_ssize_t clen;
-
- if (len > 1)
- return -EINVAL;
- if (!access_ok(uiov, sizeof(*uiov)))
- return -EFAULT;
- if (__get_user(clen, &uiov->iov_len))
- return -EFAULT;
- if (clen < 0)
- return -EINVAL;
- sr->len = clen;
- iomsg->free_iov = NULL;
- } else {
- iomsg->free_iov = iomsg->fast_iov;
- ret = __import_iovec(READ, (struct iovec __user *)uiov, len,
- UIO_FASTIOV, &iomsg->free_iov,
- &iomsg->msg.msg_iter, true);
- if (ret < 0)
- return ret;
- }
-
- return 0;
-}
-#endif
-
-static int io_recvmsg_copy_hdr(struct io_kiocb *req,
- struct io_async_msghdr *iomsg)
-{
- iomsg->msg.msg_name = &iomsg->addr;
-
-#ifdef CONFIG_COMPAT
- if (req->ctx->compat)
- return __io_compat_recvmsg_copy_hdr(req, iomsg);
-#endif
-
- return __io_recvmsg_copy_hdr(req, iomsg);
-}
-
-static struct io_buffer *io_recv_buffer_select(struct io_kiocb *req,
- unsigned int issue_flags)
-{
- struct io_sr_msg *sr = &req->sr_msg;
-
- return io_buffer_select(req, &sr->len, sr->bgid, issue_flags);
-}
-
-static inline unsigned int io_put_recv_kbuf(struct io_kiocb *req)
-{
- return io_put_kbuf(req, req->kbuf);
-}
-
-static int io_recvmsg_prep_async(struct io_kiocb *req)
-{
- int ret;
-
- ret = io_recvmsg_copy_hdr(req, req->async_data);
- if (!ret)
- req->flags |= REQ_F_NEED_CLEANUP;
- return ret;
-}
-
-static int io_recvmsg_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- struct io_sr_msg *sr = &req->sr_msg;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
-
- sr->umsg = u64_to_user_ptr(READ_ONCE(sqe->addr));
- sr->len = READ_ONCE(sqe->len);
- sr->bgid = READ_ONCE(sqe->buf_group);
- sr->msg_flags = READ_ONCE(sqe->msg_flags) | MSG_NOSIGNAL;
- if (sr->msg_flags & MSG_DONTWAIT)
- req->flags |= REQ_F_NOWAIT;
-
-#ifdef CONFIG_COMPAT
- if (req->ctx->compat)
- sr->msg_flags |= MSG_CMSG_COMPAT;
-#endif
- return 0;
-}
-
-static int io_recvmsg(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_async_msghdr iomsg, *kmsg;
- struct socket *sock;
- struct io_buffer *kbuf;
- unsigned flags;
- int min_ret = 0;
- int ret, cflags = 0;
- bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
-
- sock = sock_from_file(req->file);
- if (unlikely(!sock))
- return -ENOTSOCK;
-
- if (req_has_async_data(req)) {
- kmsg = req->async_data;
- } else {
- ret = io_recvmsg_copy_hdr(req, &iomsg);
- if (ret)
- return ret;
- kmsg = &iomsg;
- }
-
- if (req->flags & REQ_F_BUFFER_SELECT) {
- kbuf = io_recv_buffer_select(req, issue_flags);
- if (IS_ERR(kbuf))
- return PTR_ERR(kbuf);
- kmsg->fast_iov[0].iov_base = u64_to_user_ptr(kbuf->addr);
- kmsg->fast_iov[0].iov_len = req->sr_msg.len;
- iov_iter_init(&kmsg->msg.msg_iter, READ, kmsg->fast_iov,
- 1, req->sr_msg.len);
- }
-
- flags = req->sr_msg.msg_flags;
- if (force_nonblock)
- flags |= MSG_DONTWAIT;
- if (flags & MSG_WAITALL)
- min_ret = iov_iter_count(&kmsg->msg.msg_iter);
-
- ret = __sys_recvmsg_sock(sock, &kmsg->msg, req->sr_msg.umsg,
- kmsg->uaddr, flags);
- if (force_nonblock && ret == -EAGAIN)
- return io_setup_async_msg(req, kmsg);
- if (ret == -ERESTARTSYS)
- ret = -EINTR;
-
- if (req->flags & REQ_F_BUFFER_SELECTED)
- cflags = io_put_recv_kbuf(req);
- /* fast path, check for non-NULL to avoid function call */
- if (kmsg->free_iov)
- kfree(kmsg->free_iov);
- req->flags &= ~REQ_F_NEED_CLEANUP;
- if (ret < min_ret || ((flags & MSG_WAITALL) && (kmsg->msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
- req_set_fail(req);
- __io_req_complete(req, issue_flags, ret, cflags);
- return 0;
-}
-
-static int io_recv(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_buffer *kbuf;
- struct io_sr_msg *sr = &req->sr_msg;
- struct msghdr msg;
- void __user *buf = sr->buf;
- struct socket *sock;
- struct iovec iov;
- unsigned flags;
- int min_ret = 0;
- int ret, cflags = 0;
- bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
-
- sock = sock_from_file(req->file);
- if (unlikely(!sock))
- return -ENOTSOCK;
-
- if (req->flags & REQ_F_BUFFER_SELECT) {
- kbuf = io_recv_buffer_select(req, issue_flags);
- if (IS_ERR(kbuf))
- return PTR_ERR(kbuf);
- buf = u64_to_user_ptr(kbuf->addr);
- }
-
- ret = import_single_range(READ, buf, sr->len, &iov, &msg.msg_iter);
- if (unlikely(ret))
- goto out_free;
-
- msg.msg_name = NULL;
- msg.msg_control = NULL;
- msg.msg_controllen = 0;
- msg.msg_namelen = 0;
- msg.msg_iocb = NULL;
- msg.msg_flags = 0;
-
- flags = req->sr_msg.msg_flags;
- if (force_nonblock)
- flags |= MSG_DONTWAIT;
- if (flags & MSG_WAITALL)
- min_ret = iov_iter_count(&msg.msg_iter);
-
- ret = sock_recvmsg(sock, &msg, flags);
- if (force_nonblock && ret == -EAGAIN)
- return -EAGAIN;
- if (ret == -ERESTARTSYS)
- ret = -EINTR;
-out_free:
- if (req->flags & REQ_F_BUFFER_SELECTED)
- cflags = io_put_recv_kbuf(req);
- if (ret < min_ret || ((flags & MSG_WAITALL) && (msg.msg_flags & (MSG_TRUNC | MSG_CTRUNC))))
- req_set_fail(req);
- __io_req_complete(req, issue_flags, ret, cflags);
- return 0;
-}
-
-static int io_accept_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- struct io_accept *accept = &req->accept;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (sqe->ioprio || sqe->len || sqe->buf_index)
- return -EINVAL;
-
- accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
- accept->addr_len = u64_to_user_ptr(READ_ONCE(sqe->addr2));
- accept->flags = READ_ONCE(sqe->accept_flags);
- accept->nofile = rlimit(RLIMIT_NOFILE);
-
- accept->file_slot = READ_ONCE(sqe->file_index);
- if (accept->file_slot && ((req->open.how.flags & O_CLOEXEC) ||
- (accept->flags & SOCK_CLOEXEC)))
- return -EINVAL;
- if (accept->flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
- return -EINVAL;
- if (SOCK_NONBLOCK != O_NONBLOCK && (accept->flags & SOCK_NONBLOCK))
- accept->flags = (accept->flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
- return 0;
-}
-
-static int io_accept(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_accept *accept = &req->accept;
- bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
- unsigned int file_flags = force_nonblock ? O_NONBLOCK : 0;
- bool fixed = !!accept->file_slot;
- struct file *file;
- int ret, fd;
-
- if (req->file->f_flags & O_NONBLOCK)
- req->flags |= REQ_F_NOWAIT;
-
- if (!fixed) {
- fd = __get_unused_fd_flags(accept->flags, accept->nofile);
- if (unlikely(fd < 0))
- return fd;
- }
- file = do_accept(req->file, file_flags, accept->addr, accept->addr_len,
- accept->flags);
- if (IS_ERR(file)) {
- if (!fixed)
- put_unused_fd(fd);
- ret = PTR_ERR(file);
- if (ret == -EAGAIN && force_nonblock)
- return -EAGAIN;
- if (ret == -ERESTARTSYS)
- ret = -EINTR;
- req_set_fail(req);
- } else if (!fixed) {
- fd_install(fd, file);
- ret = fd;
- } else {
- ret = io_install_fixed_file(req, file, issue_flags,
- accept->file_slot - 1);
- }
- __io_req_complete(req, issue_flags, ret, 0);
- return 0;
-}
-
-static int io_connect_prep_async(struct io_kiocb *req)
-{
- struct io_async_connect *io = req->async_data;
- struct io_connect *conn = &req->connect;
-
- return move_addr_to_kernel(conn->addr, conn->addr_len, &io->address);
-}
-
-static int io_connect_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- struct io_connect *conn = &req->connect;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (sqe->ioprio || sqe->len || sqe->buf_index || sqe->rw_flags ||
- sqe->splice_fd_in)
- return -EINVAL;
-
- conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
- conn->addr_len = READ_ONCE(sqe->addr2);
- return 0;
-}
-
-static int io_connect(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_async_connect __io, *io;
- unsigned file_flags;
- int ret;
- bool force_nonblock = issue_flags & IO_URING_F_NONBLOCK;
-
- if (req_has_async_data(req)) {
- io = req->async_data;
- } else {
- ret = move_addr_to_kernel(req->connect.addr,
- req->connect.addr_len,
- &__io.address);
- if (ret)
- goto out;
- io = &__io;
- }
-
- file_flags = force_nonblock ? O_NONBLOCK : 0;
-
- ret = __sys_connect_file(req->file, &io->address,
- req->connect.addr_len, file_flags);
- if ((ret == -EAGAIN || ret == -EINPROGRESS) && force_nonblock) {
- if (req_has_async_data(req))
- return -EAGAIN;
- if (io_alloc_async_data(req)) {
- ret = -ENOMEM;
- goto out;
- }
- memcpy(req->async_data, &__io, sizeof(__io));
- return -EAGAIN;
- }
- if (ret == -ERESTARTSYS)
- ret = -EINTR;
-out:
- if (ret < 0)
- req_set_fail(req);
- __io_req_complete(req, issue_flags, ret, 0);
- return 0;
-}
-#else /* !CONFIG_NET */
-#define IO_NETOP_FN(op) \
-static int io_##op(struct io_kiocb *req, unsigned int issue_flags) \
-{ \
- return -EOPNOTSUPP; \
-}
-
-#define IO_NETOP_PREP(op) \
-IO_NETOP_FN(op) \
-static int io_##op##_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe) \
-{ \
- return -EOPNOTSUPP; \
-} \
-
-#define IO_NETOP_PREP_ASYNC(op) \
-IO_NETOP_PREP(op) \
-static int io_##op##_prep_async(struct io_kiocb *req) \
-{ \
- return -EOPNOTSUPP; \
-}
-
-IO_NETOP_PREP_ASYNC(sendmsg);
-IO_NETOP_PREP_ASYNC(recvmsg);
-IO_NETOP_PREP_ASYNC(connect);
-IO_NETOP_PREP(accept);
-IO_NETOP_FN(send);
-IO_NETOP_FN(recv);
-#endif /* CONFIG_NET */
-
-struct io_poll_table {
- struct poll_table_struct pt;
- struct io_kiocb *req;
- int nr_entries;
- int error;
-};
-
-static int __io_async_wake(struct io_kiocb *req, struct io_poll_iocb *poll,
- __poll_t mask, io_req_tw_func_t func)
-{
- /* for instances that support it check for an event match first: */
- if (mask && !(mask & poll->events))
- return 0;
-
- trace_io_uring_task_add(req->ctx, req->opcode, req->user_data, mask);
-
- list_del_init(&poll->wait.entry);
-
- req->result = mask;
- req->io_task_work.func = func;
-
- /*
- * If this fails, then the task is exiting. When a task exits, the
- * work gets canceled, so just cancel this request as well instead
- * of executing it. We can't safely execute it anyway, as we may not
- * have the needed state needed for it anyway.
- */
- io_req_task_work_add(req);
- return 1;
-}
-
-static bool io_poll_rewait(struct io_kiocb *req, struct io_poll_iocb *poll)
- __acquires(&req->ctx->completion_lock)
-{
- struct io_ring_ctx *ctx = req->ctx;
-
- /* req->task == current here, checking PF_EXITING is safe */
- if (unlikely(req->task->flags & PF_EXITING))
- WRITE_ONCE(poll->canceled, true);
-
- if (!req->result && !READ_ONCE(poll->canceled)) {
- struct poll_table_struct pt = { ._key = poll->events };
-
- req->result = vfs_poll(req->file, &pt) & poll->events;
- }
-
- spin_lock(&ctx->completion_lock);
- if (!req->result && !READ_ONCE(poll->canceled)) {
- add_wait_queue(poll->head, &poll->wait);
- return true;
- }
-
- return false;
-}
-
-static struct io_poll_iocb *io_poll_get_double(struct io_kiocb *req)
-{
- /* pure poll stashes this in ->async_data, poll driven retry elsewhere */
- if (req->opcode == IORING_OP_POLL_ADD)
- return req->async_data;
- return req->apoll->double_poll;
-}
-
-static struct io_poll_iocb *io_poll_get_single(struct io_kiocb *req)
-{
- if (req->opcode == IORING_OP_POLL_ADD)
- return &req->poll;
- return &req->apoll->poll;
-}
-
-static void io_poll_remove_double(struct io_kiocb *req)
- __must_hold(&req->ctx->completion_lock)
-{
- struct io_poll_iocb *poll = io_poll_get_double(req);
-
- lockdep_assert_held(&req->ctx->completion_lock);
-
- if (poll && poll->head) {
- struct wait_queue_head *head = poll->head;
-
- spin_lock_irq(&head->lock);
- list_del_init(&poll->wait.entry);
- if (poll->wait.private)
- req_ref_put(req);
- poll->head = NULL;
- spin_unlock_irq(&head->lock);
- }
-}
-
-static bool __io_poll_complete(struct io_kiocb *req, __poll_t mask)
- __must_hold(&req->ctx->completion_lock)
-{
- struct io_ring_ctx *ctx = req->ctx;
- unsigned flags = IORING_CQE_F_MORE;
- int error;
-
- if (READ_ONCE(req->poll.canceled)) {
- error = -ECANCELED;
- req->poll.events |= EPOLLONESHOT;
- } else {
- error = mangle_poll(mask);
- }
- if (req->poll.events & EPOLLONESHOT)
- flags = 0;
- if (!io_cqring_fill_event(ctx, req->user_data, error, flags)) {
- req->poll.events |= EPOLLONESHOT;
- flags = 0;
- }
- if (flags & IORING_CQE_F_MORE)
- ctx->cq_extra++;
-
- return !(flags & IORING_CQE_F_MORE);
-}
-
-static void io_poll_task_func(struct io_kiocb *req, bool *locked)
-{
- struct io_ring_ctx *ctx = req->ctx;
- struct io_kiocb *nxt;
-
- if (io_poll_rewait(req, &req->poll)) {
- spin_unlock(&ctx->completion_lock);
- } else {
- bool done;
-
- if (req->poll.done) {
- spin_unlock(&ctx->completion_lock);
- return;
- }
- done = __io_poll_complete(req, req->result);
- if (done) {
- io_poll_remove_double(req);
- hash_del(&req->hash_node);
- req->poll.done = true;
- } else {
- req->result = 0;
- add_wait_queue(req->poll.head, &req->poll.wait);
- }
- io_commit_cqring(ctx);
- spin_unlock(&ctx->completion_lock);
- io_cqring_ev_posted(ctx);
-
- if (done) {
- nxt = io_put_req_find_next(req);
- if (nxt)
- io_req_task_submit(nxt, locked);
- }
- }
-}
-
-static int io_poll_double_wake(struct wait_queue_entry *wait, unsigned mode,
- int sync, void *key)
-{
- struct io_kiocb *req = wait->private;
- struct io_poll_iocb *poll = io_poll_get_single(req);
- __poll_t mask = key_to_poll(key);
- unsigned long flags;
-
- /* for instances that support it check for an event match first: */
- if (mask && !(mask & poll->events))
- return 0;
- if (!(poll->events & EPOLLONESHOT))
- return poll->wait.func(&poll->wait, mode, sync, key);
-
- list_del_init(&wait->entry);
-
- if (poll->head) {
- bool done;
-
- spin_lock_irqsave(&poll->head->lock, flags);
- done = list_empty(&poll->wait.entry);
- if (!done)
- list_del_init(&poll->wait.entry);
- /* make sure double remove sees this as being gone */
- wait->private = NULL;
- spin_unlock_irqrestore(&poll->head->lock, flags);
- if (!done) {
- /* use wait func handler, so it matches the rq type */
- poll->wait.func(&poll->wait, mode, sync, key);
- }
- }
- req_ref_put(req);
- return 1;
-}
-
-static void io_init_poll_iocb(struct io_poll_iocb *poll, __poll_t events,
- wait_queue_func_t wake_func)
-{
- poll->head = NULL;
- poll->done = false;
- poll->canceled = false;
-#define IO_POLL_UNMASK (EPOLLERR|EPOLLHUP|EPOLLNVAL|EPOLLRDHUP)
- /* mask in events that we always want/need */
- poll->events = events | IO_POLL_UNMASK;
- INIT_LIST_HEAD(&poll->wait.entry);
- init_waitqueue_func_entry(&poll->wait, wake_func);
-}
-
-static void __io_queue_proc(struct io_poll_iocb *poll, struct io_poll_table *pt,
- struct wait_queue_head *head,
- struct io_poll_iocb **poll_ptr)
-{
- struct io_kiocb *req = pt->req;
-
- /*
- * The file being polled uses multiple waitqueues for poll handling
- * (e.g. one for read, one for write). Setup a separate io_poll_iocb
- * if this happens.
- */
- if (unlikely(pt->nr_entries)) {
- struct io_poll_iocb *poll_one = poll;
-
- /* double add on the same waitqueue head, ignore */
- if (poll_one->head == head)
- return;
- /* already have a 2nd entry, fail a third attempt */
- if (*poll_ptr) {
- if ((*poll_ptr)->head == head)
- return;
- pt->error = -EINVAL;
- return;
- }
- /*
- * Can't handle multishot for double wait for now, turn it
- * into one-shot mode.
- */
- if (!(poll_one->events & EPOLLONESHOT))
- poll_one->events |= EPOLLONESHOT;
- poll = kmalloc(sizeof(*poll), GFP_ATOMIC);
- if (!poll) {
- pt->error = -ENOMEM;
- return;
- }
- io_init_poll_iocb(poll, poll_one->events, io_poll_double_wake);
- req_ref_get(req);
- poll->wait.private = req;
-
- *poll_ptr = poll;
- if (req->opcode == IORING_OP_POLL_ADD)
- req->flags |= REQ_F_ASYNC_DATA;
- }
-
- pt->nr_entries++;
- poll->head = head;
-
- if (poll->events & EPOLLEXCLUSIVE)
- add_wait_queue_exclusive(head, &poll->wait);
- else
- add_wait_queue(head, &poll->wait);
-}
-
-static void io_async_queue_proc(struct file *file, struct wait_queue_head *head,
- struct poll_table_struct *p)
-{
- struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
- struct async_poll *apoll = pt->req->apoll;
-
- __io_queue_proc(&apoll->poll, pt, head, &apoll->double_poll);
-}
-
-static void io_async_task_func(struct io_kiocb *req, bool *locked)
-{
- struct async_poll *apoll = req->apoll;
- struct io_ring_ctx *ctx = req->ctx;
-
- trace_io_uring_task_run(req->ctx, req, req->opcode, req->user_data);
-
- if (io_poll_rewait(req, &apoll->poll)) {
- spin_unlock(&ctx->completion_lock);
- return;
- }
-
- hash_del(&req->hash_node);
- io_poll_remove_double(req);
- apoll->poll.done = true;
- spin_unlock(&ctx->completion_lock);
-
- if (!READ_ONCE(apoll->poll.canceled))
- io_req_task_submit(req, locked);
- else
- io_req_complete_failed(req, -ECANCELED);
-}
-
-static int io_async_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
- void *key)
-{
- struct io_kiocb *req = wait->private;
- struct io_poll_iocb *poll = &req->apoll->poll;
-
- trace_io_uring_poll_wake(req->ctx, req->opcode, req->user_data,
- key_to_poll(key));
-
- return __io_async_wake(req, poll, key_to_poll(key), io_async_task_func);
-}
-
-static void io_poll_req_insert(struct io_kiocb *req)
-{
- struct io_ring_ctx *ctx = req->ctx;
- struct hlist_head *list;
-
- list = &ctx->cancel_hash[hash_long(req->user_data, ctx->cancel_hash_bits)];
- hlist_add_head(&req->hash_node, list);
-}
-
-static __poll_t __io_arm_poll_handler(struct io_kiocb *req,
- struct io_poll_iocb *poll,
- struct io_poll_table *ipt, __poll_t mask,
- wait_queue_func_t wake_func)
- __acquires(&ctx->completion_lock)
-{
- struct io_ring_ctx *ctx = req->ctx;
- bool cancel = false;
-
- INIT_HLIST_NODE(&req->hash_node);
- io_init_poll_iocb(poll, mask, wake_func);
- poll->file = req->file;
- poll->wait.private = req;
-
- ipt->pt._key = mask;
- ipt->req = req;
- ipt->error = 0;
- ipt->nr_entries = 0;
-
- mask = vfs_poll(req->file, &ipt->pt) & poll->events;
- if (unlikely(!ipt->nr_entries) && !ipt->error)
- ipt->error = -EINVAL;
-
- spin_lock(&ctx->completion_lock);
- if (ipt->error || (mask && (poll->events & EPOLLONESHOT)))
- io_poll_remove_double(req);
- if (likely(poll->head)) {
- spin_lock_irq(&poll->head->lock);
- if (unlikely(list_empty(&poll->wait.entry))) {
- if (ipt->error)
- cancel = true;
- ipt->error = 0;
- mask = 0;
- }
- if ((mask && (poll->events & EPOLLONESHOT)) || ipt->error)
- list_del_init(&poll->wait.entry);
- else if (cancel)
- WRITE_ONCE(poll->canceled, true);
- else if (!poll->done) /* actually waiting for an event */
- io_poll_req_insert(req);
- spin_unlock_irq(&poll->head->lock);
- }
-
- return mask;
-}
-
-enum {
- IO_APOLL_OK,
- IO_APOLL_ABORTED,
- IO_APOLL_READY
-};
-
-static int io_arm_poll_handler(struct io_kiocb *req)
-{
- const struct io_op_def *def = &io_op_defs[req->opcode];
- struct io_ring_ctx *ctx = req->ctx;
- struct async_poll *apoll;
- struct io_poll_table ipt;
- __poll_t ret, mask = EPOLLONESHOT | POLLERR | POLLPRI;
-
- if (!def->pollin && !def->pollout)
- return IO_APOLL_ABORTED;
- if (!file_can_poll(req->file) || (req->flags & REQ_F_POLLED))
- return IO_APOLL_ABORTED;
-
- if (def->pollin) {
- mask |= POLLIN | POLLRDNORM;
-
- /* If reading from MSG_ERRQUEUE using recvmsg, ignore POLLIN */
- if ((req->opcode == IORING_OP_RECVMSG) &&
- (req->sr_msg.msg_flags & MSG_ERRQUEUE))
- mask &= ~POLLIN;
- } else {
- mask |= POLLOUT | POLLWRNORM;
- }
-
- apoll = kmalloc(sizeof(*apoll), GFP_ATOMIC);
- if (unlikely(!apoll))
- return IO_APOLL_ABORTED;
- apoll->double_poll = NULL;
- req->apoll = apoll;
- req->flags |= REQ_F_POLLED;
- ipt.pt._qproc = io_async_queue_proc;
- io_req_set_refcount(req);
-
- ret = __io_arm_poll_handler(req, &apoll->poll, &ipt, mask,
- io_async_wake);
- spin_unlock(&ctx->completion_lock);
- if (ret || ipt.error)
- return ret ? IO_APOLL_READY : IO_APOLL_ABORTED;
-
- trace_io_uring_poll_arm(ctx, req, req->opcode, req->user_data,
- mask, apoll->poll.events);
- return IO_APOLL_OK;
-}
-
-static bool __io_poll_remove_one(struct io_kiocb *req,
- struct io_poll_iocb *poll, bool do_cancel)
- __must_hold(&req->ctx->completion_lock)
-{
- bool do_complete = false;
-
- if (!poll->head)
- return false;
- spin_lock_irq(&poll->head->lock);
- if (do_cancel)
- WRITE_ONCE(poll->canceled, true);
- if (!list_empty(&poll->wait.entry)) {
- list_del_init(&poll->wait.entry);
- do_complete = true;
- }
- spin_unlock_irq(&poll->head->lock);
- hash_del(&req->hash_node);
- return do_complete;
-}
-
-static bool io_poll_remove_one(struct io_kiocb *req)
- __must_hold(&req->ctx->completion_lock)
-{
- bool do_complete;
-
- io_poll_remove_double(req);
- do_complete = __io_poll_remove_one(req, io_poll_get_single(req), true);
-
- if (do_complete) {
- io_cqring_fill_event(req->ctx, req->user_data, -ECANCELED, 0);
- io_commit_cqring(req->ctx);
- req_set_fail(req);
- io_put_req_deferred(req);
- }
- return do_complete;
-}
-
-/*
- * Returns true if we found and killed one or more poll requests
- */
-static __cold bool io_poll_remove_all(struct io_ring_ctx *ctx,
- struct task_struct *tsk, bool cancel_all)
-{
- struct hlist_node *tmp;
- struct io_kiocb *req;
- int posted = 0, i;
-
- spin_lock(&ctx->completion_lock);
- for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
- struct hlist_head *list;
-
- list = &ctx->cancel_hash[i];
- hlist_for_each_entry_safe(req, tmp, list, hash_node) {
- if (io_match_task_safe(req, tsk, cancel_all))
- posted += io_poll_remove_one(req);
- }
- }
- spin_unlock(&ctx->completion_lock);
-
- if (posted)
- io_cqring_ev_posted(ctx);
-
- return posted != 0;
-}
-
-static struct io_kiocb *io_poll_find(struct io_ring_ctx *ctx, __u64 sqe_addr,
- bool poll_only)
- __must_hold(&ctx->completion_lock)
-{
- struct hlist_head *list;
- struct io_kiocb *req;
-
- list = &ctx->cancel_hash[hash_long(sqe_addr, ctx->cancel_hash_bits)];
- hlist_for_each_entry(req, list, hash_node) {
- if (sqe_addr != req->user_data)
- continue;
- if (poll_only && req->opcode != IORING_OP_POLL_ADD)
- continue;
- return req;
- }
- return NULL;
-}
-
-static int io_poll_cancel(struct io_ring_ctx *ctx, __u64 sqe_addr,
- bool poll_only)
- __must_hold(&ctx->completion_lock)
-{
- struct io_kiocb *req;
-
- req = io_poll_find(ctx, sqe_addr, poll_only);
- if (!req)
- return -ENOENT;
- if (io_poll_remove_one(req))
- return 0;
-
- return -EALREADY;
-}
-
-static __poll_t io_poll_parse_events(const struct io_uring_sqe *sqe,
- unsigned int flags)
-{
- u32 events;
-
- events = READ_ONCE(sqe->poll32_events);
-#ifdef __BIG_ENDIAN
- events = swahw32(events);
-#endif
- if (!(flags & IORING_POLL_ADD_MULTI))
- events |= EPOLLONESHOT;
- return demangle_poll(events) | (events & (EPOLLEXCLUSIVE|EPOLLONESHOT));
-}
-
-static int io_poll_update_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- struct io_poll_update *upd = &req->poll_update;
- u32 flags;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
- return -EINVAL;
- flags = READ_ONCE(sqe->len);
- if (flags & ~(IORING_POLL_UPDATE_EVENTS | IORING_POLL_UPDATE_USER_DATA |
- IORING_POLL_ADD_MULTI))
- return -EINVAL;
- /* meaningless without update */
- if (flags == IORING_POLL_ADD_MULTI)
- return -EINVAL;
-
- upd->old_user_data = READ_ONCE(sqe->addr);
- upd->update_events = flags & IORING_POLL_UPDATE_EVENTS;
- upd->update_user_data = flags & IORING_POLL_UPDATE_USER_DATA;
-
- upd->new_user_data = READ_ONCE(sqe->off);
- if (!upd->update_user_data && upd->new_user_data)
- return -EINVAL;
- if (upd->update_events)
- upd->events = io_poll_parse_events(sqe, flags);
- else if (sqe->poll32_events)
- return -EINVAL;
-
- return 0;
-}
-
-static int io_poll_wake(struct wait_queue_entry *wait, unsigned mode, int sync,
- void *key)
-{
- struct io_kiocb *req = wait->private;
- struct io_poll_iocb *poll = &req->poll;
-
- return __io_async_wake(req, poll, key_to_poll(key), io_poll_task_func);
-}
-
-static void io_poll_queue_proc(struct file *file, struct wait_queue_head *head,
- struct poll_table_struct *p)
-{
- struct io_poll_table *pt = container_of(p, struct io_poll_table, pt);
-
- __io_queue_proc(&pt->req->poll, pt, head, (struct io_poll_iocb **) &pt->req->async_data);
-}
-
-static int io_poll_add_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- struct io_poll_iocb *poll = &req->poll;
- u32 flags;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (sqe->ioprio || sqe->buf_index || sqe->off || sqe->addr)
- return -EINVAL;
- flags = READ_ONCE(sqe->len);
- if (flags & ~IORING_POLL_ADD_MULTI)
- return -EINVAL;
-
- io_req_set_refcount(req);
- poll->events = io_poll_parse_events(sqe, flags);
- return 0;
-}
-
-static int io_poll_add(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_poll_iocb *poll = &req->poll;
- struct io_ring_ctx *ctx = req->ctx;
- struct io_poll_table ipt;
- __poll_t mask;
- bool done;
-
- ipt.pt._qproc = io_poll_queue_proc;
-
- mask = __io_arm_poll_handler(req, &req->poll, &ipt, poll->events,
- io_poll_wake);
-
- if (mask) { /* no async, we'd stolen it */
- ipt.error = 0;
- done = __io_poll_complete(req, mask);
- io_commit_cqring(req->ctx);
- }
- spin_unlock(&ctx->completion_lock);
-
- if (mask) {
- io_cqring_ev_posted(ctx);
- if (done)
- io_put_req(req);
- }
- return ipt.error;
-}
-
-static int io_poll_update(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_ring_ctx *ctx = req->ctx;
- struct io_kiocb *preq;
- bool completing;
- int ret;
-
- spin_lock(&ctx->completion_lock);
- preq = io_poll_find(ctx, req->poll_update.old_user_data, true);
- if (!preq) {
- ret = -ENOENT;
- goto err;
- }
-
- if (!req->poll_update.update_events && !req->poll_update.update_user_data) {
- completing = true;
- ret = io_poll_remove_one(preq) ? 0 : -EALREADY;
- goto err;
- }
-
- /*
- * Don't allow racy completion with singleshot, as we cannot safely
- * update those. For multishot, if we're racing with completion, just
- * let completion re-add it.
- */
- completing = !__io_poll_remove_one(preq, &preq->poll, false);
- if (completing && (preq->poll.events & EPOLLONESHOT)) {
- ret = -EALREADY;
- goto err;
- }
- /* we now have a detached poll request. reissue. */
- ret = 0;
-err:
- if (ret < 0) {
- spin_unlock(&ctx->completion_lock);
- req_set_fail(req);
- io_req_complete(req, ret);
- return 0;
- }
- /* only mask one event flags, keep behavior flags */
- if (req->poll_update.update_events) {
- preq->poll.events &= ~0xffff;
- preq->poll.events |= req->poll_update.events & 0xffff;
- preq->poll.events |= IO_POLL_UNMASK;
- }
- if (req->poll_update.update_user_data)
- preq->user_data = req->poll_update.new_user_data;
- spin_unlock(&ctx->completion_lock);
-
- /* complete update request, we're done with it */
- io_req_complete(req, ret);
-
- if (!completing) {
- ret = io_poll_add(preq, issue_flags);
- if (ret < 0) {
- req_set_fail(preq);
- io_req_complete(preq, ret);
- }
- }
- return 0;
-}
-
-static void io_req_task_timeout(struct io_kiocb *req, bool *locked)
-{
- struct io_timeout_data *data = req->async_data;
-
- if (!(data->flags & IORING_TIMEOUT_ETIME_SUCCESS))
- req_set_fail(req);
- io_req_complete_post(req, -ETIME, 0);
-}
-
-static enum hrtimer_restart io_timeout_fn(struct hrtimer *timer)
-{
- struct io_timeout_data *data = container_of(timer,
- struct io_timeout_data, timer);
- struct io_kiocb *req = data->req;
- struct io_ring_ctx *ctx = req->ctx;
- unsigned long flags;
-
- spin_lock_irqsave(&ctx->timeout_lock, flags);
- list_del_init(&req->timeout.list);
- atomic_set(&req->ctx->cq_timeouts,
- atomic_read(&req->ctx->cq_timeouts) + 1);
- spin_unlock_irqrestore(&ctx->timeout_lock, flags);
-
- req->io_task_work.func = io_req_task_timeout;
- io_req_task_work_add(req);
- return HRTIMER_NORESTART;
-}
-
-static struct io_kiocb *io_timeout_extract(struct io_ring_ctx *ctx,
- __u64 user_data)
- __must_hold(&ctx->timeout_lock)
-{
- struct io_timeout_data *io;
- struct io_kiocb *req;
- bool found = false;
-
- list_for_each_entry(req, &ctx->timeout_list, timeout.list) {
- found = user_data == req->user_data;
- if (found)
- break;
- }
- if (!found)
- return ERR_PTR(-ENOENT);
-
- io = req->async_data;
- if (hrtimer_try_to_cancel(&io->timer) == -1)
- return ERR_PTR(-EALREADY);
- list_del_init(&req->timeout.list);
- return req;
-}
-
-static int io_timeout_cancel(struct io_ring_ctx *ctx, __u64 user_data)
- __must_hold(&ctx->completion_lock)
- __must_hold(&ctx->timeout_lock)
-{
- struct io_kiocb *req = io_timeout_extract(ctx, user_data);
-
- if (IS_ERR(req))
- return PTR_ERR(req);
-
- req_set_fail(req);
- io_cqring_fill_event(ctx, req->user_data, -ECANCELED, 0);
- io_put_req_deferred(req);
- return 0;
-}
-
-static clockid_t io_timeout_get_clock(struct io_timeout_data *data)
-{
- switch (data->flags & IORING_TIMEOUT_CLOCK_MASK) {
- case IORING_TIMEOUT_BOOTTIME:
- return CLOCK_BOOTTIME;
- case IORING_TIMEOUT_REALTIME:
- return CLOCK_REALTIME;
- default:
- /* can't happen, vetted at prep time */
- WARN_ON_ONCE(1);
- fallthrough;
- case 0:
- return CLOCK_MONOTONIC;
- }
-}
-
-static int io_linked_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
- struct timespec64 *ts, enum hrtimer_mode mode)
- __must_hold(&ctx->timeout_lock)
-{
- struct io_timeout_data *io;
- struct io_kiocb *req;
- bool found = false;
-
- list_for_each_entry(req, &ctx->ltimeout_list, timeout.list) {
- found = user_data == req->user_data;
- if (found)
- break;
- }
- if (!found)
- return -ENOENT;
-
- io = req->async_data;
- if (hrtimer_try_to_cancel(&io->timer) == -1)
- return -EALREADY;
- hrtimer_init(&io->timer, io_timeout_get_clock(io), mode);
- io->timer.function = io_link_timeout_fn;
- hrtimer_start(&io->timer, timespec64_to_ktime(*ts), mode);
- return 0;
-}
-
-static int io_timeout_update(struct io_ring_ctx *ctx, __u64 user_data,
- struct timespec64 *ts, enum hrtimer_mode mode)
- __must_hold(&ctx->timeout_lock)
-{
- struct io_kiocb *req = io_timeout_extract(ctx, user_data);
- struct io_timeout_data *data;
-
- if (IS_ERR(req))
- return PTR_ERR(req);
-
- req->timeout.off = 0; /* noseq */
- data = req->async_data;
- list_add_tail(&req->timeout.list, &ctx->timeout_list);
- hrtimer_init(&data->timer, io_timeout_get_clock(data), mode);
- data->timer.function = io_timeout_fn;
- hrtimer_start(&data->timer, timespec64_to_ktime(*ts), mode);
- return 0;
-}
-
-static int io_timeout_remove_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- struct io_timeout_rem *tr = &req->timeout_rem;
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
- return -EINVAL;
- if (sqe->ioprio || sqe->buf_index || sqe->len || sqe->splice_fd_in)
- return -EINVAL;
-
- tr->ltimeout = false;
- tr->addr = READ_ONCE(sqe->addr);
- tr->flags = READ_ONCE(sqe->timeout_flags);
- if (tr->flags & IORING_TIMEOUT_UPDATE_MASK) {
- if (hweight32(tr->flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
- return -EINVAL;
- if (tr->flags & IORING_LINK_TIMEOUT_UPDATE)
- tr->ltimeout = true;
- if (tr->flags & ~(IORING_TIMEOUT_UPDATE_MASK|IORING_TIMEOUT_ABS))
- return -EINVAL;
- if (get_timespec64(&tr->ts, u64_to_user_ptr(sqe->addr2)))
- return -EFAULT;
- } else if (tr->flags) {
- /* timeout removal doesn't support flags */
- return -EINVAL;
- }
-
- return 0;
-}
-
-static inline enum hrtimer_mode io_translate_timeout_mode(unsigned int flags)
-{
- return (flags & IORING_TIMEOUT_ABS) ? HRTIMER_MODE_ABS
- : HRTIMER_MODE_REL;
-}
-
-/*
- * Remove or update an existing timeout command
- */
-static int io_timeout_remove(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_timeout_rem *tr = &req->timeout_rem;
- struct io_ring_ctx *ctx = req->ctx;
- int ret;
-
- if (!(req->timeout_rem.flags & IORING_TIMEOUT_UPDATE)) {
- spin_lock(&ctx->completion_lock);
- spin_lock_irq(&ctx->timeout_lock);
- ret = io_timeout_cancel(ctx, tr->addr);
- spin_unlock_irq(&ctx->timeout_lock);
- spin_unlock(&ctx->completion_lock);
- } else {
- enum hrtimer_mode mode = io_translate_timeout_mode(tr->flags);
-
- spin_lock_irq(&ctx->timeout_lock);
- if (tr->ltimeout)
- ret = io_linked_timeout_update(ctx, tr->addr, &tr->ts, mode);
- else
- ret = io_timeout_update(ctx, tr->addr, &tr->ts, mode);
- spin_unlock_irq(&ctx->timeout_lock);
- }
-
- if (ret < 0)
- req_set_fail(req);
- io_req_complete_post(req, ret, 0);
- return 0;
-}
-
-static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
- bool is_timeout_link)
-{
- struct io_timeout_data *data;
- unsigned flags;
- u32 off = READ_ONCE(sqe->off);
-
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (sqe->ioprio || sqe->buf_index || sqe->len != 1 ||
- sqe->splice_fd_in)
- return -EINVAL;
- if (off && is_timeout_link)
- return -EINVAL;
- flags = READ_ONCE(sqe->timeout_flags);
- if (flags & ~(IORING_TIMEOUT_ABS | IORING_TIMEOUT_CLOCK_MASK |
- IORING_TIMEOUT_ETIME_SUCCESS))
- return -EINVAL;
- /* more than one clock specified is invalid, obviously */
- if (hweight32(flags & IORING_TIMEOUT_CLOCK_MASK) > 1)
- return -EINVAL;
-
- INIT_LIST_HEAD(&req->timeout.list);
- req->timeout.off = off;
- if (unlikely(off && !req->ctx->off_timeout_used))
- req->ctx->off_timeout_used = true;
-
- if (WARN_ON_ONCE(req_has_async_data(req)))
- return -EFAULT;
- if (io_alloc_async_data(req))
- return -ENOMEM;
-
- data = req->async_data;
- data->req = req;
- data->flags = flags;
-
- if (get_timespec64(&data->ts, u64_to_user_ptr(sqe->addr)))
- return -EFAULT;
-
- if (data->ts.tv_sec < 0 || data->ts.tv_nsec < 0)
- return -EINVAL;
-
- data->mode = io_translate_timeout_mode(flags);
- hrtimer_init(&data->timer, io_timeout_get_clock(data), data->mode);
-
- if (is_timeout_link) {
- struct io_submit_link *link = &req->ctx->submit_state.link;
-
- if (!link->head)
- return -EINVAL;
- if (link->last->opcode == IORING_OP_LINK_TIMEOUT)
- return -EINVAL;
- req->timeout.head = link->last;
- link->last->flags |= REQ_F_ARM_LTIMEOUT;
- }
- return 0;
-}
-
-static int io_timeout(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_ring_ctx *ctx = req->ctx;
- struct io_timeout_data *data = req->async_data;
- struct list_head *entry;
- u32 tail, off = req->timeout.off;
-
- spin_lock_irq(&ctx->timeout_lock);
-
- /*
- * sqe->off holds how many events that need to occur for this
- * timeout event to be satisfied. If it isn't set, then this is
- * a pure timeout request, sequence isn't used.
- */
- if (io_is_timeout_noseq(req)) {
- entry = ctx->timeout_list.prev;
- goto add;
- }
-
- tail = ctx->cached_cq_tail - atomic_read(&ctx->cq_timeouts);
- req->timeout.target_seq = tail + off;
-
- /* Update the last seq here in case io_flush_timeouts() hasn't.
- * This is safe because ->completion_lock is held, and submissions
- * and completions are never mixed in the same ->completion_lock section.
- */
- ctx->cq_last_tm_flush = tail;
-
- /*
- * Insertion sort, ensuring the first entry in the list is always
- * the one we need first.
- */
- list_for_each_prev(entry, &ctx->timeout_list) {
- struct io_kiocb *nxt = list_entry(entry, struct io_kiocb,
- timeout.list);
-
- if (io_is_timeout_noseq(nxt))
- continue;
- /* nxt.seq is behind @tail, otherwise would've been completed */
- if (off >= nxt->timeout.target_seq - tail)
- break;
- }
-add:
- list_add(&req->timeout.list, entry);
- data->timer.function = io_timeout_fn;
- hrtimer_start(&data->timer, timespec64_to_ktime(data->ts), data->mode);
- spin_unlock_irq(&ctx->timeout_lock);
- return 0;
-}
-
-struct io_cancel_data {
- struct io_ring_ctx *ctx;
- u64 user_data;
-};
-
-static bool io_cancel_cb(struct io_wq_work *work, void *data)
-{
- struct io_kiocb *req = container_of(work, struct io_kiocb, work);
- struct io_cancel_data *cd = data;
-
- return req->ctx == cd->ctx && req->user_data == cd->user_data;
-}
-
-static int io_async_cancel_one(struct io_uring_task *tctx, u64 user_data,
- struct io_ring_ctx *ctx)
-{
- struct io_cancel_data data = { .ctx = ctx, .user_data = user_data, };
- enum io_wq_cancel cancel_ret;
- int ret = 0;
-
- if (!tctx || !tctx->io_wq)
- return -ENOENT;
-
- cancel_ret = io_wq_cancel_cb(tctx->io_wq, io_cancel_cb, &data, false);
- switch (cancel_ret) {
- case IO_WQ_CANCEL_OK:
- ret = 0;
- break;
- case IO_WQ_CANCEL_RUNNING:
- ret = -EALREADY;
- break;
- case IO_WQ_CANCEL_NOTFOUND:
- ret = -ENOENT;
- break;
- }
-
- return ret;
-}
-
-static int io_try_cancel_userdata(struct io_kiocb *req, u64 sqe_addr)
-{
- struct io_ring_ctx *ctx = req->ctx;
- int ret;
-
- WARN_ON_ONCE(!io_wq_current_is_worker() && req->task != current);
-
- ret = io_async_cancel_one(req->task->io_uring, sqe_addr, ctx);
- if (ret != -ENOENT)
- return ret;
-
- spin_lock(&ctx->completion_lock);
- spin_lock_irq(&ctx->timeout_lock);
- ret = io_timeout_cancel(ctx, sqe_addr);
- spin_unlock_irq(&ctx->timeout_lock);
- if (ret != -ENOENT)
- goto out;
- ret = io_poll_cancel(ctx, sqe_addr, false);
-out:
- spin_unlock(&ctx->completion_lock);
- return ret;
-}
-
-static int io_async_cancel_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
- return -EINVAL;
- if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
- return -EINVAL;
- if (sqe->ioprio || sqe->off || sqe->len || sqe->cancel_flags ||
- sqe->splice_fd_in)
- return -EINVAL;
-
- req->cancel.addr = READ_ONCE(sqe->addr);
- return 0;
-}
-
-static int io_async_cancel(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_ring_ctx *ctx = req->ctx;
- u64 sqe_addr = req->cancel.addr;
- bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
- struct io_tctx_node *node;
- int ret;
-
- ret = io_try_cancel_userdata(req, sqe_addr);
- if (ret != -ENOENT)
- goto done;
-
- /* slow path, try all io-wq's */
- io_ring_submit_lock(ctx, needs_lock);
- ret = -ENOENT;
- list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
- struct io_uring_task *tctx = node->task->io_uring;
-
- ret = io_async_cancel_one(tctx, req->cancel.addr, ctx);
- if (ret != -ENOENT)
- break;
- }
- io_ring_submit_unlock(ctx, needs_lock);
-done:
- if (ret < 0)
- req_set_fail(req);
- io_req_complete_post(req, ret, 0);
- return 0;
-}
-
-static int io_rsrc_update_prep(struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
-{
- if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
- return -EINVAL;
- if (sqe->ioprio || sqe->rw_flags || sqe->splice_fd_in)
- return -EINVAL;
-
- req->rsrc_update.offset = READ_ONCE(sqe->off);
- req->rsrc_update.nr_args = READ_ONCE(sqe->len);
- if (!req->rsrc_update.nr_args)
- return -EINVAL;
- req->rsrc_update.arg = READ_ONCE(sqe->addr);
- return 0;
-}
-
-static int io_files_update(struct io_kiocb *req, unsigned int issue_flags)
-{
- struct io_ring_ctx *ctx = req->ctx;
- bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
- struct io_uring_rsrc_update2 up;
- int ret;
-
- up.offset = req->rsrc_update.offset;
- up.data = req->rsrc_update.arg;
- up.nr = 0;
- up.tags = 0;
- up.resv = 0;
-
- io_ring_submit_lock(ctx, needs_lock);
- ret = __io_register_rsrc_update(ctx, IORING_RSRC_FILE,
- &up, req->rsrc_update.nr_args);
- io_ring_submit_unlock(ctx, needs_lock);
-
- if (ret < 0)
- req_set_fail(req);
- __io_req_complete(req, issue_flags, ret, 0);
- return 0;
-}
-
-static int io_req_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
-{
- switch (req->opcode) {
- case IORING_OP_NOP:
- return 0;
- case IORING_OP_READV:
- case IORING_OP_READ_FIXED:
- case IORING_OP_READ:
- return io_read_prep(req, sqe);
- case IORING_OP_WRITEV:
- case IORING_OP_WRITE_FIXED:
- case IORING_OP_WRITE:
- return io_write_prep(req, sqe);
- case IORING_OP_POLL_ADD:
- return io_poll_add_prep(req, sqe);
- case IORING_OP_POLL_REMOVE:
- return io_poll_update_prep(req, sqe);
- case IORING_OP_FSYNC:
- return io_fsync_prep(req, sqe);
- case IORING_OP_SYNC_FILE_RANGE:
- return io_sfr_prep(req, sqe);
- case IORING_OP_SENDMSG:
- case IORING_OP_SEND:
- return io_sendmsg_prep(req, sqe);
- case IORING_OP_RECVMSG:
- case IORING_OP_RECV:
- return io_recvmsg_prep(req, sqe);
- case IORING_OP_CONNECT:
- return io_connect_prep(req, sqe);
- case IORING_OP_TIMEOUT:
- return io_timeout_prep(req, sqe, false);
- case IORING_OP_TIMEOUT_REMOVE:
- return io_timeout_remove_prep(req, sqe);
- case IORING_OP_ASYNC_CANCEL:
- return io_async_cancel_prep(req, sqe);
- case IORING_OP_LINK_TIMEOUT:
- return io_timeout_prep(req, sqe, true);
- case IORING_OP_ACCEPT:
- return io_accept_prep(req, sqe);
- case IORING_OP_FALLOCATE:
- return io_fallocate_prep(req, sqe);
- case IORING_OP_OPENAT:
- return io_openat_prep(req, sqe);
- case IORING_OP_CLOSE:
- return io_close_prep(req, sqe);
- case IORING_OP_FILES_UPDATE:
- return io_rsrc_update_prep(req, sqe);
- case IORING_OP_STATX:
- return io_statx_prep(req, sqe);
- case IORING_OP_FADVISE:
- return io_fadvise_prep(req, sqe);
- case IORING_OP_MADVISE:
- return io_madvise_prep(req, sqe);
- case IORING_OP_OPENAT2:
- return io_openat2_prep(req, sqe);
- case IORING_OP_EPOLL_CTL:
- return io_epoll_ctl_prep(req, sqe);
- case IORING_OP_SPLICE:
- return io_splice_prep(req, sqe);
- case IORING_OP_PROVIDE_BUFFERS:
- return io_provide_buffers_prep(req, sqe);
- case IORING_OP_REMOVE_BUFFERS:
- return io_remove_buffers_prep(req, sqe);
- case IORING_OP_TEE:
- return io_tee_prep(req, sqe);
- case IORING_OP_SHUTDOWN:
- return io_shutdown_prep(req, sqe);
- case IORING_OP_RENAMEAT:
- return io_renameat_prep(req, sqe);
- case IORING_OP_UNLINKAT:
- return io_unlinkat_prep(req, sqe);
- case IORING_OP_MKDIRAT:
- return io_mkdirat_prep(req, sqe);
- case IORING_OP_SYMLINKAT:
- return io_symlinkat_prep(req, sqe);
- case IORING_OP_LINKAT:
- return io_linkat_prep(req, sqe);
- }
-
- printk_once(KERN_WARNING "io_uring: unhandled opcode %d\n",
- req->opcode);
- return -EINVAL;
-}
-
-static int io_req_prep_async(struct io_kiocb *req)
-{
- if (!io_op_defs[req->opcode].needs_async_setup)
- return 0;
- if (WARN_ON_ONCE(req_has_async_data(req)))
- return -EFAULT;
- if (io_alloc_async_data(req))
- return -EAGAIN;
-
- switch (req->opcode) {
- case IORING_OP_READV:
- return io_rw_prep_async(req, READ);
- case IORING_OP_WRITEV:
- return io_rw_prep_async(req, WRITE);
- case IORING_OP_SENDMSG:
- return io_sendmsg_prep_async(req);
- case IORING_OP_RECVMSG:
- return io_recvmsg_prep_async(req);
- case IORING_OP_CONNECT:
- return io_connect_prep_async(req);
- }
- printk_once(KERN_WARNING "io_uring: prep_async() bad opcode %d\n",
- req->opcode);
- return -EFAULT;
-}
-
-static u32 io_get_sequence(struct io_kiocb *req)
-{
- u32 seq = req->ctx->cached_sq_head;
-
- /* need original cached_sq_head, but it was increased for each req */
- io_for_each_link(req, req)
- seq--;
- return seq;
-}
-
-static __cold void io_drain_req(struct io_kiocb *req)
-{
- struct io_ring_ctx *ctx = req->ctx;
- struct io_defer_entry *de;
- int ret;
- u32 seq = io_get_sequence(req);
-
- /* Still need defer if there is pending req in defer list. */
- if (!req_need_defer(req, seq) && list_empty_careful(&ctx->defer_list)) {
-queue:
- ctx->drain_active = false;
- io_req_task_queue(req);
- return;
- }
-
- ret = io_req_prep_async(req);
- if (ret) {
-fail:
- io_req_complete_failed(req, ret);
- return;
- }
- io_prep_async_link(req);
- de = kmalloc(sizeof(*de), GFP_KERNEL);
- if (!de) {
- ret = -ENOMEM;
- goto fail;
- }
-
- spin_lock(&ctx->completion_lock);
- if (!req_need_defer(req, seq) && list_empty(&ctx->defer_list)) {
- spin_unlock(&ctx->completion_lock);
- kfree(de);
- goto queue;
- }
-
- trace_io_uring_defer(ctx, req, req->user_data);
- de->req = req;
- de->seq = seq;
- list_add_tail(&de->list, &ctx->defer_list);
- spin_unlock(&ctx->completion_lock);
-}
-
-static void io_clean_op(struct io_kiocb *req)
-{
- if (req->flags & REQ_F_BUFFER_SELECTED) {
- kfree(req->kbuf);
- req->kbuf = NULL;
- }
-
- if (req->flags & REQ_F_NEED_CLEANUP) {
- switch (req->opcode) {
- case IORING_OP_READV:
- case IORING_OP_READ_FIXED:
- case IORING_OP_READ:
- case IORING_OP_WRITEV:
- case IORING_OP_WRITE_FIXED:
- case IORING_OP_WRITE: {
- struct io_async_rw *io = req->async_data;
-
- kfree(io->free_iovec);
- break;
- }
- case IORING_OP_RECVMSG:
- case IORING_OP_SENDMSG: {
- struct io_async_msghdr *io = req->async_data;
-
- kfree(io->free_iov);
- break;
- }
- case IORING_OP_SPLICE:
- case IORING_OP_TEE:
- if (!(req->splice.flags & SPLICE_F_FD_IN_FIXED))
- io_put_file(req->splice.file_in);
- break;
- case IORING_OP_OPENAT:
- case IORING_OP_OPENAT2:
- if (req->open.filename)
- putname(req->open.filename);
- break;
- case IORING_OP_RENAMEAT:
- putname(req->rename.oldpath);
- putname(req->rename.newpath);
- break;
- case IORING_OP_UNLINKAT:
- putname(req->unlink.filename);
- break;
- case IORING_OP_MKDIRAT:
- putname(req->mkdir.filename);
- break;
- case IORING_OP_SYMLINKAT:
- putname(req->symlink.oldpath);
- putname(req->symlink.newpath);
- break;
- case IORING_OP_LINKAT:
- putname(req->hardlink.oldpath);
- putname(req->hardlink.newpath);
- break;
- }
- }
- if ((req->flags & REQ_F_POLLED) && req->apoll) {
- kfree(req->apoll->double_poll);
- kfree(req->apoll);
- req->apoll = NULL;
- }
- if (req->flags & REQ_F_INFLIGHT) {
- struct io_uring_task *tctx = req->task->io_uring;
-
- atomic_dec(&tctx->inflight_tracked);
- }
- if (req->flags & REQ_F_CREDS)
- put_cred(req->creds);
- if (req->flags & REQ_F_ASYNC_DATA) {
- kfree(req->async_data);
- req->async_data = NULL;
- }
- req->flags &= ~IO_REQ_CLEAN_FLAGS;
-}
-
-static int io_issue_sqe(struct io_kiocb *req, unsigned int issue_flags)
-{
- const struct cred *creds = NULL;
- int ret;
-
- if (unlikely((req->flags & REQ_F_CREDS) && req->creds != current_cred()))
- creds = override_creds(req->creds);
-
- if (!io_op_defs[req->opcode].audit_skip)
- audit_uring_entry(req->opcode);
-
- switch (req->opcode) {
- case IORING_OP_NOP:
- ret = io_nop(req, issue_flags);
- break;
- case IORING_OP_READV:
- case IORING_OP_READ_FIXED:
- case IORING_OP_READ:
- ret = io_read(req, issue_flags);
- break;
- case IORING_OP_WRITEV:
- case IORING_OP_WRITE_FIXED:
- case IORING_OP_WRITE:
- ret = io_write(req, issue_flags);
- break;
- case IORING_OP_FSYNC:
- ret = io_fsync(req, issue_flags);
- break;
- case IORING_OP_POLL_ADD:
- ret = io_poll_add(req, issue_flags);
- break;
- case IORING_OP_POLL_REMOVE:
- ret = io_poll_update(req, issue_flags);
- break;
- case IORING_OP_SYNC_FILE_RANGE:
- ret = io_sync_file_range(req, issue_flags);
- break;
- case IORING_OP_SENDMSG:
- ret = io_sendmsg(req, issue_flags);
- break;
- case IORING_OP_SEND:
- ret = io_send(req, issue_flags);
- break;
- case IORING_OP_RECVMSG:
- ret = io_recvmsg(req, issue_flags);
- break;
- case IORING_OP_RECV:
- ret = io_recv(req, issue_flags);
- break;
- case IORING_OP_TIMEOUT:
- ret = io_timeout(req, issue_flags);
- break;
- case IORING_OP_TIMEOUT_REMOVE:
- ret = io_timeout_remove(req, issue_flags);
- break;
- case IORING_OP_ACCEPT:
- ret = io_accept(req, issue_flags);
- break;
- case IORING_OP_CONNECT:
- ret = io_connect(req, issue_flags);
- break;
- case IORING_OP_ASYNC_CANCEL:
- ret = io_async_cancel(req, issue_flags);
- break;
- case IORING_OP_FALLOCATE:
- ret = io_fallocate(req, issue_flags);
- break;
- case IORING_OP_OPENAT:
- ret = io_openat(req, issue_flags);
- break;
- case IORING_OP_CLOSE:
- ret = io_close(req, issue_flags);
- break;
- case IORING_OP_FILES_UPDATE:
- ret = io_files_update(req, issue_flags);
- break;
- case IORING_OP_STATX:
- ret = io_statx(req, issue_flags);
- break;
- case IORING_OP_FADVISE:
- ret = io_fadvise(req, issue_flags);
- break;
- case IORING_OP_MADVISE:
- ret = io_madvise(req, issue_flags);
- break;
- case IORING_OP_OPENAT2:
- ret = io_openat2(req, issue_flags);
- break;
- case IORING_OP_EPOLL_CTL:
- ret = io_epoll_ctl(req, issue_flags);
- break;
- case IORING_OP_SPLICE:
- ret = io_splice(req, issue_flags);
- break;
- case IORING_OP_PROVIDE_BUFFERS:
- ret = io_provide_buffers(req, issue_flags);
- break;
- case IORING_OP_REMOVE_BUFFERS:
- ret = io_remove_buffers(req, issue_flags);
- break;
- case IORING_OP_TEE:
- ret = io_tee(req, issue_flags);
- break;
- case IORING_OP_SHUTDOWN:
- ret = io_shutdown(req, issue_flags);
- break;
- case IORING_OP_RENAMEAT:
- ret = io_renameat(req, issue_flags);
- break;
- case IORING_OP_UNLINKAT:
- ret = io_unlinkat(req, issue_flags);
- break;
- case IORING_OP_MKDIRAT:
- ret = io_mkdirat(req, issue_flags);
- break;
- case IORING_OP_SYMLINKAT:
- ret = io_symlinkat(req, issue_flags);
- break;
- case IORING_OP_LINKAT:
- ret = io_linkat(req, issue_flags);
- break;
- default:
- ret = -EINVAL;
- break;
- }
-
- if (!io_op_defs[req->opcode].audit_skip)
- audit_uring_exit(!ret, ret);
-
- if (creds)
- revert_creds(creds);
- if (ret)
- return ret;
- /* If the op doesn't have a file, we're not polling for it */
- if ((req->ctx->flags & IORING_SETUP_IOPOLL) && req->file)
- io_iopoll_req_issued(req, issue_flags);
-
- return 0;
-}
-
-static struct io_wq_work *io_wq_free_work(struct io_wq_work *work)
-{
- struct io_kiocb *req = container_of(work, struct io_kiocb, work);
-
- req = io_put_req_find_next(req);
- return req ? &req->work : NULL;
-}
-
-static void io_wq_submit_work(struct io_wq_work *work)
-{
- struct io_kiocb *req = container_of(work, struct io_kiocb, work);
- unsigned int issue_flags = IO_URING_F_UNLOCKED;
- bool needs_poll = false;
- struct io_kiocb *timeout;
- int ret = 0;
-
- /* one will be dropped by ->io_free_work() after returning to io-wq */
- if (!(req->flags & REQ_F_REFCOUNT))
- __io_req_set_refcount(req, 2);
- else
- req_ref_get(req);
-
- timeout = io_prep_linked_timeout(req);
- if (timeout)
- io_queue_linked_timeout(timeout);
-
- /* either cancelled or io-wq is dying, so don't touch tctx->iowq */
- if (work->flags & IO_WQ_WORK_CANCEL) {
- io_req_task_queue_fail(req, -ECANCELED);
- return;
- }
-
- if (req->flags & REQ_F_FORCE_ASYNC) {
- const struct io_op_def *def = &io_op_defs[req->opcode];
- bool opcode_poll = def->pollin || def->pollout;
-
- if (opcode_poll && file_can_poll(req->file)) {
- needs_poll = true;
- issue_flags |= IO_URING_F_NONBLOCK;
- }
- }
-
- do {
- ret = io_issue_sqe(req, issue_flags);
- if (ret != -EAGAIN)
- break;
- /*
- * We can get EAGAIN for iopolled IO even though we're
- * forcing a sync submission from here, since we can't
- * wait for request slots on the block side.
- */
- if (!needs_poll) {
- cond_resched();
- continue;
- }
-
- if (io_arm_poll_handler(req) == IO_APOLL_OK)
- return;
- /* aborted or ready, in either case retry blocking */
- needs_poll = false;
- issue_flags &= ~IO_URING_F_NONBLOCK;
- } while (1);
-
- /* avoid locking problems by failing it from a clean context */
- if (ret)
- io_req_task_queue_fail(req, ret);
-}
-
-static inline struct io_fixed_file *io_fixed_file_slot(struct io_file_table *table,
- unsigned i)
-{
- return &table->files[i];
-}
-
-static inline struct file *io_file_from_index(struct io_ring_ctx *ctx,
- int index)
-{
- struct io_fixed_file *slot = io_fixed_file_slot(&ctx->file_table, index);
-
- return (struct file *) (slot->file_ptr & FFS_MASK);
-}
-
-static void io_fixed_file_set(struct io_fixed_file *file_slot, struct file *file)
-{
- unsigned long file_ptr = (unsigned long) file;
-
- file_ptr |= io_file_get_flags(file);
- file_slot->file_ptr = file_ptr;
-}
-
-static inline struct file *io_file_get_fixed(struct io_ring_ctx *ctx,
- struct io_kiocb *req, int fd)
-{
- struct file *file;
- unsigned long file_ptr;
-
- if (unlikely((unsigned int)fd >= ctx->nr_user_files))
- return NULL;
- fd = array_index_nospec(fd, ctx->nr_user_files);
- file_ptr = io_fixed_file_slot(&ctx->file_table, fd)->file_ptr;
- file = (struct file *) (file_ptr & FFS_MASK);
- file_ptr &= ~FFS_MASK;
- /* mask in overlapping REQ_F and FFS bits */
- req->flags |= (file_ptr << REQ_F_SUPPORT_NOWAIT_BIT);
- io_req_set_rsrc_node(req, ctx);
- return file;
-}
-
-static struct file *io_file_get_normal(struct io_ring_ctx *ctx,
- struct io_kiocb *req, int fd)
-{
- struct file *file = fget(fd);
-
- trace_io_uring_file_get(ctx, fd);
-
- /* we don't allow fixed io_uring files */
- if (file && unlikely(file->f_op == &io_uring_fops))
- io_req_track_inflight(req);
- return file;
-}
-
-static inline struct file *io_file_get(struct io_ring_ctx *ctx,
- struct io_kiocb *req, int fd, bool fixed)
-{
- if (fixed)
- return io_file_get_fixed(ctx, req, fd);
- else
- return io_file_get_normal(ctx, req, fd);
-}
-
-static void io_req_task_link_timeout(struct io_kiocb *req, bool *locked)
-{
- struct io_kiocb *prev = req->timeout.prev;
- int ret = -ENOENT;
-
- if (prev) {
- if (!(req->task->flags & PF_EXITING))
- ret = io_try_cancel_userdata(req, prev->user_data);
- io_req_complete_post(req, ret ?: -ETIME, 0);
- io_put_req(prev);
- } else {
- io_req_complete_post(req, -ETIME, 0);
- }
-}
-
-static enum hrtimer_restart io_link_timeout_fn(struct hrtimer *timer)
-{
- struct io_timeout_data *data = container_of(timer,
- struct io_timeout_data, timer);
- struct io_kiocb *prev, *req = data->req;
- struct io_ring_ctx *ctx = req->ctx;
- unsigned long flags;
-
- spin_lock_irqsave(&ctx->timeout_lock, flags);
- prev = req->timeout.head;
- req->timeout.head = NULL;
-
- /*
- * We don't expect the list to be empty, that will only happen if we
- * race with the completion of the linked work.
- */
- if (prev) {
- io_remove_next_linked(prev);
- if (!req_ref_inc_not_zero(prev))
- prev = NULL;
- }
- list_del(&req->timeout.list);
- req->timeout.prev = prev;
- spin_unlock_irqrestore(&ctx->timeout_lock, flags);
-
- req->io_task_work.func = io_req_task_link_timeout;
- io_req_task_work_add(req);
- return HRTIMER_NORESTART;
-}
-
-static void io_queue_linked_timeout(struct io_kiocb *req)
-{
- struct io_ring_ctx *ctx = req->ctx;
-
- spin_lock_irq(&ctx->timeout_lock);
- /*
- * If the back reference is NULL, then our linked request finished
- * before we got a chance to setup the timer
- */
- if (req->timeout.head) {
- struct io_timeout_data *data = req->async_data;
-
- data->timer.function = io_link_timeout_fn;
- hrtimer_start(&data->timer, timespec64_to_ktime(data->ts),
- data->mode);
- list_add_tail(&req->timeout.list, &ctx->ltimeout_list);
- }
- spin_unlock_irq(&ctx->timeout_lock);
- /* drop submission reference */
- io_put_req(req);
-}
-
-static void io_queue_sqe_arm_apoll(struct io_kiocb *req)
- __must_hold(&req->ctx->uring_lock)
-{
- struct io_kiocb *linked_timeout = io_prep_linked_timeout(req);
-
- switch (io_arm_poll_handler(req)) {
- case IO_APOLL_READY:
- io_req_task_queue(req);
- break;
- case IO_APOLL_ABORTED:
- /*
- * Queued up for async execution, worker will release
- * submit reference when the iocb is actually submitted.
- */
- io_queue_async_work(req, NULL);
- break;
- }
-
- if (linked_timeout)
- io_queue_linked_timeout(linked_timeout);
-}
-
-static inline void __io_queue_sqe(struct io_kiocb *req)
- __must_hold(&req->ctx->uring_lock)
-{
- struct io_kiocb *linked_timeout;
- int ret;
-
- ret = io_issue_sqe(req, IO_URING_F_NONBLOCK|IO_URING_F_COMPLETE_DEFER);
-
- if (req->flags & REQ_F_COMPLETE_INLINE) {
- io_req_add_compl_list(req);
- return;
- }
- /*
- * We async punt it if the file wasn't marked NOWAIT, or if the file
- * doesn't support non-blocking read/write attempts
- */
- if (likely(!ret)) {
- linked_timeout = io_prep_linked_timeout(req);
- if (linked_timeout)
- io_queue_linked_timeout(linked_timeout);
- } else if (ret == -EAGAIN && !(req->flags & REQ_F_NOWAIT)) {
- io_queue_sqe_arm_apoll(req);
- } else {
- io_req_complete_failed(req, ret);
- }
-}
-
-static void io_queue_sqe_fallback(struct io_kiocb *req)
- __must_hold(&req->ctx->uring_lock)
-{
- if (req->flags & REQ_F_FAIL) {
- io_req_complete_fail_submit(req);
- } else if (unlikely(req->ctx->drain_active)) {
- io_drain_req(req);
- } else {
- int ret = io_req_prep_async(req);
-
- if (unlikely(ret))
- io_req_complete_failed(req, ret);
- else
- io_queue_async_work(req, NULL);
- }
-}
-
-static inline void io_queue_sqe(struct io_kiocb *req)
- __must_hold(&req->ctx->uring_lock)
-{
- if (likely(!(req->flags & (REQ_F_FORCE_ASYNC | REQ_F_FAIL))))
- __io_queue_sqe(req);
- else
- io_queue_sqe_fallback(req);
-}
-
-/*
- * Check SQE restrictions (opcode and flags).
- *
- * Returns 'true' if SQE is allowed, 'false' otherwise.
- */
-static inline bool io_check_restriction(struct io_ring_ctx *ctx,
- struct io_kiocb *req,
- unsigned int sqe_flags)
-{
- if (!test_bit(req->opcode, ctx->restrictions.sqe_op))
- return false;
-
- if ((sqe_flags & ctx->restrictions.sqe_flags_required) !=
- ctx->restrictions.sqe_flags_required)
- return false;
-
- if (sqe_flags & ~(ctx->restrictions.sqe_flags_allowed |
- ctx->restrictions.sqe_flags_required))
- return false;
-
- return true;
-}
-
-static void io_init_req_drain(struct io_kiocb *req)
-{
- struct io_ring_ctx *ctx = req->ctx;
- struct io_kiocb *head = ctx->submit_state.link.head;
-
- ctx->drain_active = true;
- if (head) {
- /*
- * If we need to drain a request in the middle of a link, drain
- * the head request and the next request/link after the current
- * link. Considering sequential execution of links,
- * IOSQE_IO_DRAIN will be maintained for every request of our
- * link.
- */
- head->flags |= IOSQE_IO_DRAIN | REQ_F_FORCE_ASYNC;
- ctx->drain_next = true;
- }
-}
-
-static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
- __must_hold(&ctx->uring_lock)
-{
- unsigned int sqe_flags;
- int personality;
- u8 opcode;
-
- /* req is partially pre-initialised, see io_preinit_req() */
- req->opcode = opcode = READ_ONCE(sqe->opcode);
- /* same numerical values with corresponding REQ_F_*, safe to copy */
- req->flags = sqe_flags = READ_ONCE(sqe->flags);
- req->user_data = READ_ONCE(sqe->user_data);
- req->file = NULL;
- req->fixed_rsrc_refs = NULL;
- req->task = current;
-
- if (unlikely(opcode >= IORING_OP_LAST)) {
- req->opcode = 0;
- return -EINVAL;
- }
- if (unlikely(sqe_flags & ~SQE_COMMON_FLAGS)) {
- /* enforce forwards compatibility on users */
- if (sqe_flags & ~SQE_VALID_FLAGS)
- return -EINVAL;
- if ((sqe_flags & IOSQE_BUFFER_SELECT) &&
- !io_op_defs[opcode].buffer_select)
- return -EOPNOTSUPP;
- if (sqe_flags & IOSQE_IO_DRAIN)
- io_init_req_drain(req);
- }
- if (unlikely(ctx->restricted || ctx->drain_active || ctx->drain_next)) {
- if (ctx->restricted && !io_check_restriction(ctx, req, sqe_flags))
- return -EACCES;
- /* knock it to the slow queue path, will be drained there */
- if (ctx->drain_active)
- req->flags |= REQ_F_FORCE_ASYNC;
- /* if there is no link, we're at "next" request and need to drain */
- if (unlikely(ctx->drain_next) && !ctx->submit_state.link.head) {
- ctx->drain_next = false;
- ctx->drain_active = true;
- req->flags |= IOSQE_IO_DRAIN | REQ_F_FORCE_ASYNC;
- }
- }
-
- if (io_op_defs[opcode].needs_file) {
- struct io_submit_state *state = &ctx->submit_state;
-
- /*
- * Plug now if we have more than 2 IO left after this, and the
- * target is potentially a read/write to block based storage.
- */
- if (state->need_plug && io_op_defs[opcode].plug) {
- state->plug_started = true;
- state->need_plug = false;
- blk_start_plug_nr_ios(&state->plug, state->submit_nr);
- }
-
- req->file = io_file_get(ctx, req, READ_ONCE(sqe->fd),
- (sqe_flags & IOSQE_FIXED_FILE));
- if (unlikely(!req->file))
- return -EBADF;
- }
-
- personality = READ_ONCE(sqe->personality);
- if (personality) {
- int ret;
-
- req->creds = xa_load(&ctx->personalities, personality);
- if (!req->creds)
- return -EINVAL;
- get_cred(req->creds);
- ret = security_uring_override_creds(req->creds);
- if (ret) {
- put_cred(req->creds);
- return ret;
- }
- req->flags |= REQ_F_CREDS;
- }
-
- return io_req_prep(req, sqe);
-}
-
-static int io_submit_sqe(struct io_ring_ctx *ctx, struct io_kiocb *req,
- const struct io_uring_sqe *sqe)
- __must_hold(&ctx->uring_lock)
-{
- struct io_submit_link *link = &ctx->submit_state.link;
- int ret;
-
- ret = io_init_req(ctx, req, sqe);
- if (unlikely(ret)) {
- trace_io_uring_req_failed(sqe, ret);
-
- /* fail even hard links since we don't submit */
- if (link->head) {
- /*
- * we can judge a link req is failed or cancelled by if
- * REQ_F_FAIL is set, but the head is an exception since
- * it may be set REQ_F_FAIL because of other req's failure
- * so let's leverage req->result to distinguish if a head
- * is set REQ_F_FAIL because of its failure or other req's
- * failure so that we can set the correct ret code for it.
- * init result here to avoid affecting the normal path.
- */
- if (!(link->head->flags & REQ_F_FAIL))
- req_fail_link_node(link->head, -ECANCELED);
- } else if (!(req->flags & (REQ_F_LINK | REQ_F_HARDLINK))) {
- /*
- * the current req is a normal req, we should return
- * error and thus break the submittion loop.
- */
- io_req_complete_failed(req, ret);
- return ret;
- }
- req_fail_link_node(req, ret);
- }
-
- /* don't need @sqe from now on */
- trace_io_uring_submit_sqe(ctx, req, req->opcode, req->user_data,
- req->flags, true,
- ctx->flags & IORING_SETUP_SQPOLL);
-
- /*
- * If we already have a head request, queue this one for async
- * submittal once the head completes. If we don't have a head but
- * IOSQE_IO_LINK is set in the sqe, start a new head. This one will be
- * submitted sync once the chain is complete. If none of those
- * conditions are true (normal request), then just queue it.
- */
- if (link->head) {
- struct io_kiocb *head = link->head;
-
- if (!(req->flags & REQ_F_FAIL)) {
- ret = io_req_prep_async(req);
- if (unlikely(ret)) {
- req_fail_link_node(req, ret);
- if (!(head->flags & REQ_F_FAIL))
- req_fail_link_node(head, -ECANCELED);
- }
- }
- trace_io_uring_link(ctx, req, head);
- link->last->link = req;
- link->last = req;
-
- if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK))
- return 0;
- /* last request of a link, enqueue the link */
- link->head = NULL;
- req = head;
- } else if (req->flags & (REQ_F_LINK | REQ_F_HARDLINK)) {
- link->head = req;
- link->last = req;
- return 0;
- }
-
- io_queue_sqe(req);
- return 0;
-}
-
-/*
- * Batched submission is done, ensure local IO is flushed out.
- */
-static void io_submit_state_end(struct io_ring_ctx *ctx)
-{
- struct io_submit_state *state = &ctx->submit_state;
-
- if (state->link.head)
- io_queue_sqe(state->link.head);
- /* flush only after queuing links as they can generate completions */
- io_submit_flush_completions(ctx);
- if (state->plug_started)
- blk_finish_plug(&state->plug);
-}
-
-/*
- * Start submission side cache.
- */
-static void io_submit_state_start(struct io_submit_state *state,
- unsigned int max_ios)
-{
- state->plug_started = false;
- state->need_plug = max_ios > 2;
- state->submit_nr = max_ios;
- /* set only head, no need to init link_last in advance */
- state->link.head = NULL;
-}
-
-static void io_commit_sqring(struct io_ring_ctx *ctx)
-{
- struct io_rings *rings = ctx->rings;
-
- /*
- * Ensure any loads from the SQEs are done at this point,
- * since once we write the new head, the application could
- * write new data to them.
- */
- smp_store_release(&rings->sq.head, ctx->cached_sq_head);
-}
-
-/*
- * Fetch an sqe, if one is available. Note this returns a pointer to memory
- * that is mapped by userspace. This means that care needs to be taken to
- * ensure that reads are stable, as we cannot rely on userspace always
- * being a good citizen. If members of the sqe are validated and then later
- * used, it's important that those reads are done through READ_ONCE() to
- * prevent a re-load down the line.
- */
-static const struct io_uring_sqe *io_get_sqe(struct io_ring_ctx *ctx)
-{
- unsigned head, mask = ctx->sq_entries - 1;
- unsigned sq_idx = ctx->cached_sq_head++ & mask;
-
- /*
- * The cached sq head (or cq tail) serves two purposes:
- *
- * 1) allows us to batch the cost of updating the user visible
- * head updates.
- * 2) allows the kernel side to track the head on its own, even
- * though the application is the one updating it.
- */
- head = READ_ONCE(ctx->sq_array[sq_idx]);
- if (likely(head < ctx->sq_entries))
- return &ctx->sq_sqes[head];
-
- /* drop invalid entries */
- ctx->cq_extra--;
- WRITE_ONCE(ctx->rings->sq_dropped,
- READ_ONCE(ctx->rings->sq_dropped) + 1);
- return NULL;
-}
-
-static int io_submit_sqes(struct io_ring_ctx *ctx, unsigned int nr)
- __must_hold(&ctx->uring_lock)
-{
- unsigned int entries = io_sqring_entries(ctx);
- int submitted = 0;
-
- if (unlikely(!entries))
- return 0;
- /* make sure SQ entry isn't read before tail */
- nr = min3(nr, ctx->sq_entries, entries);
- io_get_task_refs(nr);
-
- io_submit_state_start(&ctx->submit_state, nr);
- do {
- const struct io_uring_sqe *sqe;
- struct io_kiocb *req;
-
- if (unlikely(!io_alloc_req_refill(ctx))) {
- if (!submitted)
- submitted = -EAGAIN;
- break;
- }
- req = io_alloc_req(ctx);
- sqe = io_get_sqe(ctx);
- if (unlikely(!sqe)) {
- wq_stack_add_head(&req->comp_list, &ctx->submit_state.free_list);
- break;
- }
- /* will complete beyond this point, count as submitted */
- submitted++;
- if (io_submit_sqe(ctx, req, sqe))
- break;
- } while (submitted < nr);
-
- if (unlikely(submitted != nr)) {
- int ref_used = (submitted == -EAGAIN) ? 0 : submitted;
- int unused = nr - ref_used;
-
- current->io_uring->cached_refs += unused;
- }
-
- io_submit_state_end(ctx);
- /* Commit SQ ring head once we've consumed and submitted all SQEs */
- io_commit_sqring(ctx);
-
- return submitted;
-}
-
-static inline bool io_sqd_events_pending(struct io_sq_data *sqd)
-{
- return READ_ONCE(sqd->state);
-}
-
-static inline void io_ring_set_wakeup_flag(struct io_ring_ctx *ctx)
-{
- /* Tell userspace we may need a wakeup call */
- spin_lock(&ctx->completion_lock);
- WRITE_ONCE(ctx->rings->sq_flags,
- ctx->rings->sq_flags | IORING_SQ_NEED_WAKEUP);
- spin_unlock(&ctx->completion_lock);
-}
-
-static inline void io_ring_clear_wakeup_flag(struct io_ring_ctx *ctx)
-{
- spin_lock(&ctx->completion_lock);
- WRITE_ONCE(ctx->rings->sq_flags,
- ctx->rings->sq_flags & ~IORING_SQ_NEED_WAKEUP);
- spin_unlock(&ctx->completion_lock);
-}
-
-static int __io_sq_thread(struct io_ring_ctx *ctx, bool cap_entries)
-{
- unsigned int to_submit;
- int ret = 0;
-
- to_submit = io_sqring_entries(ctx);
- /* if we're handling multiple rings, cap submit size for fairness */
- if (cap_entries && to_submit > IORING_SQPOLL_CAP_ENTRIES_VALUE)
- to_submit = IORING_SQPOLL_CAP_ENTRIES_VALUE;
-
- if (!wq_list_empty(&ctx->iopoll_list) || to_submit) {
- const struct cred *creds = NULL;
-
- if (ctx->sq_creds != current_cred())
- creds = override_creds(ctx->sq_creds);
-
- mutex_lock(&ctx->uring_lock);
- if (!wq_list_empty(&ctx->iopoll_list))
- io_do_iopoll(ctx, true);
-
- /*
- * Don't submit if refs are dying, good for io_uring_register(),
- * but also it is relied upon by io_ring_exit_work()
- */
- if (to_submit && likely(!percpu_ref_is_dying(&ctx->refs)) &&
- !(ctx->flags & IORING_SETUP_R_DISABLED))
- ret = io_submit_sqes(ctx, to_submit);
- mutex_unlock(&ctx->uring_lock);
-
- if (to_submit && wq_has_sleeper(&ctx->sqo_sq_wait))
- wake_up(&ctx->sqo_sq_wait);
- if (creds)
- revert_creds(creds);
- }
-
- return ret;
-}
-
-static __cold void io_sqd_update_thread_idle(struct io_sq_data *sqd)
-{
- struct io_ring_ctx *ctx;
- unsigned sq_thread_idle = 0;
-
- list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
- sq_thread_idle = max(sq_thread_idle, ctx->sq_thread_idle);
- sqd->sq_thread_idle = sq_thread_idle;
-}
-
-static bool io_sqd_handle_event(struct io_sq_data *sqd)
-{
- bool did_sig = false;
- struct ksignal ksig;
-
- if (test_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state) ||
- signal_pending(current)) {
- mutex_unlock(&sqd->lock);
- if (signal_pending(current))
- did_sig = get_signal(&ksig);
- cond_resched();
- mutex_lock(&sqd->lock);
- }
- return did_sig || test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
-}
-
-static int io_sq_thread(void *data)
-{
- struct io_sq_data *sqd = data;
- struct io_ring_ctx *ctx;
- unsigned long timeout = 0;
- char buf[TASK_COMM_LEN];
- DEFINE_WAIT(wait);
-
- snprintf(buf, sizeof(buf), "iou-sqp-%d", sqd->task_pid);
- set_task_comm(current, buf);
-
- if (sqd->sq_cpu != -1)
- set_cpus_allowed_ptr(current, cpumask_of(sqd->sq_cpu));
- else
- set_cpus_allowed_ptr(current, cpu_online_mask);
- current->flags |= PF_NO_SETAFFINITY;
-
- audit_alloc_kernel(current);
-
- mutex_lock(&sqd->lock);
- while (1) {
- bool cap_entries, sqt_spin = false;
-
- if (io_sqd_events_pending(sqd) || signal_pending(current)) {
- if (io_sqd_handle_event(sqd))
- break;
- timeout = jiffies + sqd->sq_thread_idle;
- }
-
- cap_entries = !list_is_singular(&sqd->ctx_list);
- list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
- int ret = __io_sq_thread(ctx, cap_entries);
-
- if (!sqt_spin && (ret > 0 || !wq_list_empty(&ctx->iopoll_list)))
- sqt_spin = true;
- }
- if (io_run_task_work())
- sqt_spin = true;
-
- if (sqt_spin || !time_after(jiffies, timeout)) {
- cond_resched();
- if (sqt_spin)
- timeout = jiffies + sqd->sq_thread_idle;
- continue;
- }
-
- prepare_to_wait(&sqd->wait, &wait, TASK_INTERRUPTIBLE);
- if (!io_sqd_events_pending(sqd) && !current->task_works) {
- bool needs_sched = true;
-
- list_for_each_entry(ctx, &sqd->ctx_list, sqd_list) {
- io_ring_set_wakeup_flag(ctx);
-
- if ((ctx->flags & IORING_SETUP_IOPOLL) &&
- !wq_list_empty(&ctx->iopoll_list)) {
- needs_sched = false;
- break;
- }
- if (io_sqring_entries(ctx)) {
- needs_sched = false;
- break;
- }
- }
-
- if (needs_sched) {
- mutex_unlock(&sqd->lock);
- schedule();
- mutex_lock(&sqd->lock);
- }
- list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
- io_ring_clear_wakeup_flag(ctx);
- }
-
- finish_wait(&sqd->wait, &wait);
- timeout = jiffies + sqd->sq_thread_idle;
- }
-
- io_uring_cancel_generic(true, sqd);
- sqd->thread = NULL;
- list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
- io_ring_set_wakeup_flag(ctx);
- io_run_task_work();
- mutex_unlock(&sqd->lock);
-
- audit_free(current);
-
- complete(&sqd->exited);
- do_exit(0);
-}
-
-struct io_wait_queue {
- struct wait_queue_entry wq;
- struct io_ring_ctx *ctx;
- unsigned cq_tail;
- unsigned nr_timeouts;
-};
-
-static inline bool io_should_wake(struct io_wait_queue *iowq)
-{
- struct io_ring_ctx *ctx = iowq->ctx;
- int dist = ctx->cached_cq_tail - (int) iowq->cq_tail;
-
- /*
- * Wake up if we have enough events, or if a timeout occurred since we
- * started waiting. For timeouts, we always want to return to userspace,
- * regardless of event count.
- */
- return dist >= 0 || atomic_read(&ctx->cq_timeouts) != iowq->nr_timeouts;
-}
-
-static int io_wake_function(struct wait_queue_entry *curr, unsigned int mode,
- int wake_flags, void *key)
-{
- struct io_wait_queue *iowq = container_of(curr, struct io_wait_queue,
- wq);
-
- /*
- * Cannot safely flush overflowed CQEs from here, ensure we wake up
- * the task, and the next invocation will do it.
- */
- if (io_should_wake(iowq) || test_bit(0, &iowq->ctx->check_cq_overflow))
- return autoremove_wake_function(curr, mode, wake_flags, key);
- return -1;
-}
-
-static int io_run_task_work_sig(void)
-{
- if (io_run_task_work())
- return 1;
- if (!signal_pending(current))
- return 0;
- if (test_thread_flag(TIF_NOTIFY_SIGNAL))
- return -ERESTARTSYS;
- return -EINTR;
-}
-
-/* when returns >0, the caller should retry */
-static inline int io_cqring_wait_schedule(struct io_ring_ctx *ctx,
- struct io_wait_queue *iowq,
- signed long *timeout)
-{
- int ret;
-
- /* make sure we run task_work before checking for signals */
- ret = io_run_task_work_sig();
- if (ret || io_should_wake(iowq))
- return ret;
- /* let the caller flush overflows, retry */
- if (test_bit(0, &ctx->check_cq_overflow))
- return 1;
-
- *timeout = schedule_timeout(*timeout);
- return !*timeout ? -ETIME : 1;
-}
-
-/*
- * Wait until events become available, if we don't already have some. The
- * application must reap them itself, as they reside on the shared cq ring.
- */
-static int io_cqring_wait(struct io_ring_ctx *ctx, int min_events,
- const sigset_t __user *sig, size_t sigsz,
- struct __kernel_timespec __user *uts)
-{
- struct io_wait_queue iowq;
- struct io_rings *rings = ctx->rings;
- signed long timeout = MAX_SCHEDULE_TIMEOUT;
- int ret;
-
- do {
- io_cqring_overflow_flush(ctx);
- if (io_cqring_events(ctx) >= min_events)
- return 0;
- if (!io_run_task_work())
- break;
- } while (1);
-
- if (uts) {
- struct timespec64 ts;
-
- if (get_timespec64(&ts, uts))
- return -EFAULT;
- timeout = timespec64_to_jiffies(&ts);
- }
-
- if (sig) {
-#ifdef CONFIG_COMPAT
- if (in_compat_syscall())
- ret = set_compat_user_sigmask((const compat_sigset_t __user *)sig,
- sigsz);
- else
-#endif
- ret = set_user_sigmask(sig, sigsz);
-
- if (ret)
- return ret;
- }
-
- init_waitqueue_func_entry(&iowq.wq, io_wake_function);
- iowq.wq.private = current;
- INIT_LIST_HEAD(&iowq.wq.entry);
- iowq.ctx = ctx;
- iowq.nr_timeouts = atomic_read(&ctx->cq_timeouts);
- iowq.cq_tail = READ_ONCE(ctx->rings->cq.head) + min_events;
-
- trace_io_uring_cqring_wait(ctx, min_events);
- do {
- /* if we can't even flush overflow, don't wait for more */
- if (!io_cqring_overflow_flush(ctx)) {
- ret = -EBUSY;
- break;
- }
- prepare_to_wait_exclusive(&ctx->cq_wait, &iowq.wq,
- TASK_INTERRUPTIBLE);
- ret = io_cqring_wait_schedule(ctx, &iowq, &timeout);
- finish_wait(&ctx->cq_wait, &iowq.wq);
- cond_resched();
- } while (ret > 0);
-
- restore_saved_sigmask_unless(ret == -EINTR);
-
- return READ_ONCE(rings->cq.head) == READ_ONCE(rings->cq.tail) ? ret : 0;
-}
-
-static void io_free_page_table(void **table, size_t size)
-{
- unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
-
- for (i = 0; i < nr_tables; i++)
- kfree(table[i]);
- kfree(table);
-}
-
-static __cold void **io_alloc_page_table(size_t size)
-{
- unsigned i, nr_tables = DIV_ROUND_UP(size, PAGE_SIZE);
- size_t init_size = size;
- void **table;
-
- table = kcalloc(nr_tables, sizeof(*table), GFP_KERNEL_ACCOUNT);
- if (!table)
- return NULL;
-
- for (i = 0; i < nr_tables; i++) {
- unsigned int this_size = min_t(size_t, size, PAGE_SIZE);
-
- table[i] = kzalloc(this_size, GFP_KERNEL_ACCOUNT);
- if (!table[i]) {
- io_free_page_table(table, init_size);
- return NULL;
- }
- size -= this_size;
- }
- return table;
-}
-
-static void io_rsrc_node_destroy(struct io_rsrc_node *ref_node)
-{
- percpu_ref_exit(&ref_node->refs);
- kfree(ref_node);
-}
-
-static __cold void io_rsrc_node_ref_zero(struct percpu_ref *ref)
-{
- struct io_rsrc_node *node = container_of(ref, struct io_rsrc_node, refs);
- struct io_ring_ctx *ctx = node->rsrc_data->ctx;
- unsigned long flags;
- bool first_add = false;
-
- spin_lock_irqsave(&ctx->rsrc_ref_lock, flags);
- node->done = true;
-
- while (!list_empty(&ctx->rsrc_ref_list)) {
- node = list_first_entry(&ctx->rsrc_ref_list,
- struct io_rsrc_node, node);
- /* recycle ref nodes in order */
- if (!node->done)
- break;
- list_del(&node->node);
- first_add |= llist_add(&node->llist, &ctx->rsrc_put_llist);
- }
- spin_unlock_irqrestore(&ctx->rsrc_ref_lock, flags);
-
- if (first_add)
- mod_delayed_work(system_wq, &ctx->rsrc_put_work, HZ);
-}
-
-static struct io_rsrc_node *io_rsrc_node_alloc(struct io_ring_ctx *ctx)
-{
- struct io_rsrc_node *ref_node;
-
- ref_node = kzalloc(sizeof(*ref_node), GFP_KERNEL);
- if (!ref_node)
- return NULL;
-
- if (percpu_ref_init(&ref_node->refs, io_rsrc_node_ref_zero,
- 0, GFP_KERNEL)) {
- kfree(ref_node);
- return NULL;
- }
- INIT_LIST_HEAD(&ref_node->node);
- INIT_LIST_HEAD(&ref_node->rsrc_list);
- ref_node->done = false;
- return ref_node;
-}
-
-static void io_rsrc_node_switch(struct io_ring_ctx *ctx,
- struct io_rsrc_data *data_to_kill)
- __must_hold(&ctx->uring_lock)
-{
- WARN_ON_ONCE(!ctx->rsrc_backup_node);
- WARN_ON_ONCE(data_to_kill && !ctx->rsrc_node);
-
- io_rsrc_refs_drop(ctx);
-
- if (data_to_kill) {
- struct io_rsrc_node *rsrc_node = ctx->rsrc_node;
-
- rsrc_node->rsrc_data = data_to_kill;
- spin_lock_irq(&ctx->rsrc_ref_lock);
- list_add_tail(&rsrc_node->node, &ctx->rsrc_ref_list);
- spin_unlock_irq(&ctx->rsrc_ref_lock);
-
- atomic_inc(&data_to_kill->refs);
- percpu_ref_kill(&rsrc_node->refs);
- ctx->rsrc_node = NULL;
- }
-
- if (!ctx->rsrc_node) {
- ctx->rsrc_node = ctx->rsrc_backup_node;
- ctx->rsrc_backup_node = NULL;
- }
-}
-
-static int io_rsrc_node_switch_start(struct io_ring_ctx *ctx)
-{
- if (ctx->rsrc_backup_node)
- return 0;
- ctx->rsrc_backup_node = io_rsrc_node_alloc(ctx);
- return ctx->rsrc_backup_node ? 0 : -ENOMEM;
-}
-
-static __cold int io_rsrc_ref_quiesce(struct io_rsrc_data *data,
- struct io_ring_ctx *ctx)
-{
- int ret;
-
- /* As we may drop ->uring_lock, other task may have started quiesce */
- if (data->quiesce)
- return -ENXIO;
-
- data->quiesce = true;
- do {
- ret = io_rsrc_node_switch_start(ctx);
- if (ret)
- break;
- io_rsrc_node_switch(ctx, data);
-
- /* kill initial ref, already quiesced if zero */
- if (atomic_dec_and_test(&data->refs))
- break;
- mutex_unlock(&ctx->uring_lock);
- flush_delayed_work(&ctx->rsrc_put_work);
- ret = wait_for_completion_interruptible(&data->done);
- if (!ret) {
- mutex_lock(&ctx->uring_lock);
- break;
- }
-
- atomic_inc(&data->refs);
- /* wait for all works potentially completing data->done */
- flush_delayed_work(&ctx->rsrc_put_work);
- reinit_completion(&data->done);
-
- ret = io_run_task_work_sig();
- mutex_lock(&ctx->uring_lock);
- } while (ret >= 0);
- data->quiesce = false;
-
- return ret;
-}
-
-static u64 *io_get_tag_slot(struct io_rsrc_data *data, unsigned int idx)
-{
- unsigned int off = idx & IO_RSRC_TAG_TABLE_MASK;
- unsigned int table_idx = idx >> IO_RSRC_TAG_TABLE_SHIFT;
-
- return &data->tags[table_idx][off];
-}
-
-static void io_rsrc_data_free(struct io_rsrc_data *data)
-{
- size_t size = data->nr * sizeof(data->tags[0][0]);
-
- if (data->tags)
- io_free_page_table((void **)data->tags, size);
- kfree(data);
-}
-
-static __cold int io_rsrc_data_alloc(struct io_ring_ctx *ctx, rsrc_put_fn *do_put,
- u64 __user *utags, unsigned nr,
- struct io_rsrc_data **pdata)
-{
- struct io_rsrc_data *data;
- int ret = -ENOMEM;
- unsigned i;
-
- data = kzalloc(sizeof(*data), GFP_KERNEL);
- if (!data)
- return -ENOMEM;
- data->tags = (u64 **)io_alloc_page_table(nr * sizeof(data->tags[0][0]));
- if (!data->tags) {
- kfree(data);
- return -ENOMEM;
- }
-
- data->nr = nr;
- data->ctx = ctx;
- data->do_put = do_put;
- if (utags) {
- ret = -EFAULT;
- for (i = 0; i < nr; i++) {
- u64 *tag_slot = io_get_tag_slot(data, i);
-
- if (copy_from_user(tag_slot, &utags[i],
- sizeof(*tag_slot)))
- goto fail;
- }
- }
-
- atomic_set(&data->refs, 1);
- init_completion(&data->done);
- *pdata = data;
- return 0;
-fail:
- io_rsrc_data_free(data);
- return ret;
-}
-
-static bool io_alloc_file_tables(struct io_file_table *table, unsigned nr_files)
-{
- table->files = kvcalloc(nr_files, sizeof(table->files[0]),
- GFP_KERNEL_ACCOUNT);
- return !!table->files;
-}
-
-static void io_free_file_tables(struct io_file_table *table)
-{
- kvfree(table->files);
- table->files = NULL;
-}
-
-static void __io_sqe_files_unregister(struct io_ring_ctx *ctx)
-{
-#if defined(CONFIG_UNIX)
- if (ctx->ring_sock) {
- struct sock *sock = ctx->ring_sock->sk;
- struct sk_buff *skb;
-
- while ((skb = skb_dequeue(&sock->sk_receive_queue)) != NULL)
- kfree_skb(skb);
- }
-#else
- int i;
-
- for (i = 0; i < ctx->nr_user_files; i++) {
- struct file *file;
-
- file = io_file_from_index(ctx, i);
- if (file)
- fput(file);
- }
-#endif
- io_free_file_tables(&ctx->file_table);
- io_rsrc_data_free(ctx->file_data);
- ctx->file_data = NULL;
- ctx->nr_user_files = 0;
-}
-
-static int io_sqe_files_unregister(struct io_ring_ctx *ctx)
-{
- int ret;
-
- if (!ctx->file_data)
- return -ENXIO;
- ret = io_rsrc_ref_quiesce(ctx->file_data, ctx);
- if (!ret)
- __io_sqe_files_unregister(ctx);
- return ret;
-}
-
-static void io_sq_thread_unpark(struct io_sq_data *sqd)
- __releases(&sqd->lock)
-{
- WARN_ON_ONCE(sqd->thread == current);
-
- /*
- * Do the dance but not conditional clear_bit() because it'd race with
- * other threads incrementing park_pending and setting the bit.
- */
- clear_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
- if (atomic_dec_return(&sqd->park_pending))
- set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
- mutex_unlock(&sqd->lock);
-}
-
-static void io_sq_thread_park(struct io_sq_data *sqd)
- __acquires(&sqd->lock)
-{
- WARN_ON_ONCE(sqd->thread == current);
-
- atomic_inc(&sqd->park_pending);
- set_bit(IO_SQ_THREAD_SHOULD_PARK, &sqd->state);
- mutex_lock(&sqd->lock);
- if (sqd->thread)
- wake_up_process(sqd->thread);
-}
-
-static void io_sq_thread_stop(struct io_sq_data *sqd)
-{
- WARN_ON_ONCE(sqd->thread == current);
- WARN_ON_ONCE(test_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state));
-
- set_bit(IO_SQ_THREAD_SHOULD_STOP, &sqd->state);
- mutex_lock(&sqd->lock);
- if (sqd->thread)
- wake_up_process(sqd->thread);
- mutex_unlock(&sqd->lock);
- wait_for_completion(&sqd->exited);
-}
-
-static void io_put_sq_data(struct io_sq_data *sqd)
-{
- if (refcount_dec_and_test(&sqd->refs)) {
- WARN_ON_ONCE(atomic_read(&sqd->park_pending));
-
- io_sq_thread_stop(sqd);
- kfree(sqd);
- }
-}
-
-static void io_sq_thread_finish(struct io_ring_ctx *ctx)
-{
- struct io_sq_data *sqd = ctx->sq_data;
-
- if (sqd) {
- io_sq_thread_park(sqd);
- list_del_init(&ctx->sqd_list);
- io_sqd_update_thread_idle(sqd);
- io_sq_thread_unpark(sqd);
-
- io_put_sq_data(sqd);
- ctx->sq_data = NULL;
- }
-}
-
-static struct io_sq_data *io_attach_sq_data(struct io_uring_params *p)
-{
- struct io_ring_ctx *ctx_attach;
- struct io_sq_data *sqd;
- struct fd f;
-
- f = fdget(p->wq_fd);
- if (!f.file)
- return ERR_PTR(-ENXIO);
- if (f.file->f_op != &io_uring_fops) {
- fdput(f);
- return ERR_PTR(-EINVAL);
- }
-
- ctx_attach = f.file->private_data;
- sqd = ctx_attach->sq_data;
- if (!sqd) {
- fdput(f);
- return ERR_PTR(-EINVAL);
- }
- if (sqd->task_tgid != current->tgid) {
- fdput(f);
- return ERR_PTR(-EPERM);
- }
-
- refcount_inc(&sqd->refs);
- fdput(f);
- return sqd;
-}
-
-static struct io_sq_data *io_get_sq_data(struct io_uring_params *p,
- bool *attached)
-{
- struct io_sq_data *sqd;
-
- *attached = false;
- if (p->flags & IORING_SETUP_ATTACH_WQ) {
- sqd = io_attach_sq_data(p);
- if (!IS_ERR(sqd)) {
- *attached = true;
- return sqd;
- }
- /* fall through for EPERM case, setup new sqd/task */
- if (PTR_ERR(sqd) != -EPERM)
- return sqd;
- }
-
- sqd = kzalloc(sizeof(*sqd), GFP_KERNEL);
- if (!sqd)
- return ERR_PTR(-ENOMEM);
-
- atomic_set(&sqd->park_pending, 0);
- refcount_set(&sqd->refs, 1);
- INIT_LIST_HEAD(&sqd->ctx_list);
- mutex_init(&sqd->lock);
- init_waitqueue_head(&sqd->wait);
- init_completion(&sqd->exited);
- return sqd;
-}
-
-#if defined(CONFIG_UNIX)
-/*
- * Ensure the UNIX gc is aware of our file set, so we are certain that
- * the io_uring can be safely unregistered on process exit, even if we have
- * loops in the file referencing.
- */
-static int __io_sqe_files_scm(struct io_ring_ctx *ctx, int nr, int offset)
-{
- struct sock *sk = ctx->ring_sock->sk;
- struct scm_fp_list *fpl;
- struct sk_buff *skb;
- int i, nr_files;
-
- fpl = kzalloc(sizeof(*fpl), GFP_KERNEL);
- if (!fpl)
- return -ENOMEM;
-
- skb = alloc_skb(0, GFP_KERNEL);
- if (!skb) {
- kfree(fpl);
- return -ENOMEM;
- }
-
- skb->sk = sk;
-
- nr_files = 0;
- fpl->user = get_uid(current_user());
- for (i = 0; i < nr; i++) {
- struct file *file = io_file_from_index(ctx, i + offset);
-
- if (!file)
- continue;
- fpl->fp[nr_files] = get_file(file);
- unix_inflight(fpl->user, fpl->fp[nr_files]);
- nr_files++;
- }
-
- if (nr_files) {
- fpl->max = SCM_MAX_FD;
- fpl->count = nr_files;
- UNIXCB(skb).fp = fpl;
- skb->destructor = unix_destruct_scm;
- refcount_add(skb->truesize, &sk->sk_wmem_alloc);
- skb_queue_head(&sk->sk_receive_queue, skb);
-
- for (i = 0; i < nr_files; i++)
- fput(fpl->fp[i]);
- } else {
- kfree_skb(skb);
- kfree(fpl);
- }
-
- return 0;
-}
-
-/*
- * If UNIX sockets are enabled, fd passing can cause a reference cycle which
- * causes regular reference counting to break down. We rely on the UNIX
- * garbage collection to take care of this problem for us.
- */
-static int io_sqe_files_scm(struct io_ring_ctx *ctx)
-{
- unsigned left, total;
- int ret = 0;
-
- total = 0;
- left = ctx->nr_user_files;
- while (left) {
- unsigned this_files = min_t(unsigned, left, SCM_MAX_FD);
-
- ret = __io_sqe_files_scm(ctx, this_files, total);
- if (ret)
- break;
- left -= this_files;
- total += this_files;
- }
-
- if (!ret)
- return 0;
-
- while (total < ctx->nr_user_files) {
- struct file *file = io_file_from_index(ctx, total);
-
- if (file)
- fput(file);
- total++;
- }
-
- return ret;
-}
-#else
-static int io_sqe_files_scm(struct io_ring_ctx *ctx)
-{
- return 0;
-}
-#endif
-
-static void io_rsrc_file_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
-{
- struct file *file = prsrc->file;
-#if defined(CONFIG_UNIX)
- struct sock *sock = ctx->ring_sock->sk;
- struct sk_buff_head list, *head = &sock->sk_receive_queue;
- struct sk_buff *skb;
- int i;
-
- __skb_queue_head_init(&list);
-
- /*
- * Find the skb that holds this file in its SCM_RIGHTS. When found,
- * remove this entry and rearrange the file array.
- */
- skb = skb_dequeue(head);
- while (skb) {
- struct scm_fp_list *fp;
-
- fp = UNIXCB(skb).fp;
- for (i = 0; i < fp->count; i++) {
- int left;
-
- if (fp->fp[i] != file)
- continue;
-
- unix_notinflight(fp->user, fp->fp[i]);
- left = fp->count - 1 - i;
- if (left) {
- memmove(&fp->fp[i], &fp->fp[i + 1],
- left * sizeof(struct file *));
- }
- fp->count--;
- if (!fp->count) {
- kfree_skb(skb);
- skb = NULL;
- } else {
- __skb_queue_tail(&list, skb);
- }
- fput(file);
- file = NULL;
- break;
- }
-
- if (!file)
- break;
-
- __skb_queue_tail(&list, skb);
-
- skb = skb_dequeue(head);
- }
-
- if (skb_peek(&list)) {
- spin_lock_irq(&head->lock);
- while ((skb = __skb_dequeue(&list)) != NULL)
- __skb_queue_tail(head, skb);
- spin_unlock_irq(&head->lock);
- }
-#else
- fput(file);
-#endif
-}
-
-static void __io_rsrc_put_work(struct io_rsrc_node *ref_node)
-{
- struct io_rsrc_data *rsrc_data = ref_node->rsrc_data;
- struct io_ring_ctx *ctx = rsrc_data->ctx;
- struct io_rsrc_put *prsrc, *tmp;
-
- list_for_each_entry_safe(prsrc, tmp, &ref_node->rsrc_list, list) {
- list_del(&prsrc->list);
-
- if (prsrc->tag) {
- bool lock_ring = ctx->flags & IORING_SETUP_IOPOLL;
-
- io_ring_submit_lock(ctx, lock_ring);
- spin_lock(&ctx->completion_lock);
- io_cqring_fill_event(ctx, prsrc->tag, 0, 0);
- ctx->cq_extra++;
- io_commit_cqring(ctx);
- spin_unlock(&ctx->completion_lock);
- io_cqring_ev_posted(ctx);
- io_ring_submit_unlock(ctx, lock_ring);
- }
-
- rsrc_data->do_put(ctx, prsrc);
- kfree(prsrc);
- }
-
- io_rsrc_node_destroy(ref_node);
- if (atomic_dec_and_test(&rsrc_data->refs))
- complete(&rsrc_data->done);
-}
-
-static void io_rsrc_put_work(struct work_struct *work)
-{
- struct io_ring_ctx *ctx;
- struct llist_node *node;
-
- ctx = container_of(work, struct io_ring_ctx, rsrc_put_work.work);
- node = llist_del_all(&ctx->rsrc_put_llist);
-
- while (node) {
- struct io_rsrc_node *ref_node;
- struct llist_node *next = node->next;
-
- ref_node = llist_entry(node, struct io_rsrc_node, llist);
- __io_rsrc_put_work(ref_node);
- node = next;
- }
-}
-
-static int io_sqe_files_register(struct io_ring_ctx *ctx, void __user *arg,
- unsigned nr_args, u64 __user *tags)
-{
- __s32 __user *fds = (__s32 __user *) arg;
- struct file *file;
- int fd, ret;
- unsigned i;
-
- if (ctx->file_data)
- return -EBUSY;
- if (!nr_args)
- return -EINVAL;
- if (nr_args > IORING_MAX_FIXED_FILES)
- return -EMFILE;
- if (nr_args > rlimit(RLIMIT_NOFILE))
- return -EMFILE;
- ret = io_rsrc_node_switch_start(ctx);
- if (ret)
- return ret;
- ret = io_rsrc_data_alloc(ctx, io_rsrc_file_put, tags, nr_args,
- &ctx->file_data);
- if (ret)
- return ret;
-
- ret = -ENOMEM;
- if (!io_alloc_file_tables(&ctx->file_table, nr_args))
- goto out_free;
-
- for (i = 0; i < nr_args; i++, ctx->nr_user_files++) {
- if (copy_from_user(&fd, &fds[i], sizeof(fd))) {
- ret = -EFAULT;
- goto out_fput;
- }
- /* allow sparse sets */
- if (fd == -1) {
- ret = -EINVAL;
- if (unlikely(*io_get_tag_slot(ctx->file_data, i)))
- goto out_fput;
- continue;
- }
-
- file = fget(fd);
- ret = -EBADF;
- if (unlikely(!file))
- goto out_fput;
-
- /*
- * Don't allow io_uring instances to be registered. If UNIX
- * isn't enabled, then this causes a reference cycle and this
- * instance can never get freed. If UNIX is enabled we'll
- * handle it just fine, but there's still no point in allowing
- * a ring fd as it doesn't support regular read/write anyway.
- */
- if (file->f_op == &io_uring_fops) {
- fput(file);
- goto out_fput;
- }
- io_fixed_file_set(io_fixed_file_slot(&ctx->file_table, i), file);
- }
-
- ret = io_sqe_files_scm(ctx);
- if (ret) {
- __io_sqe_files_unregister(ctx);
- return ret;
- }
-
- io_rsrc_node_switch(ctx, NULL);
- return ret;
-out_fput:
- for (i = 0; i < ctx->nr_user_files; i++) {
- file = io_file_from_index(ctx, i);
- if (file)
- fput(file);
- }
- io_free_file_tables(&ctx->file_table);
- ctx->nr_user_files = 0;
-out_free:
- io_rsrc_data_free(ctx->file_data);
- ctx->file_data = NULL;
- return ret;
-}
-
-static int io_sqe_file_register(struct io_ring_ctx *ctx, struct file *file,
- int index)
-{
-#if defined(CONFIG_UNIX)
- struct sock *sock = ctx->ring_sock->sk;
- struct sk_buff_head *head = &sock->sk_receive_queue;
- struct sk_buff *skb;
-
- /*
- * See if we can merge this file into an existing skb SCM_RIGHTS
- * file set. If there's no room, fall back to allocating a new skb
- * and filling it in.
- */
- spin_lock_irq(&head->lock);
- skb = skb_peek(head);
- if (skb) {
- struct scm_fp_list *fpl = UNIXCB(skb).fp;
-
- if (fpl->count < SCM_MAX_FD) {
- __skb_unlink(skb, head);
- spin_unlock_irq(&head->lock);
- fpl->fp[fpl->count] = get_file(file);
- unix_inflight(fpl->user, fpl->fp[fpl->count]);
- fpl->count++;
- spin_lock_irq(&head->lock);
- __skb_queue_head(head, skb);
- } else {
- skb = NULL;
- }
- }
- spin_unlock_irq(&head->lock);
-
- if (skb) {
- fput(file);
- return 0;
- }
-
- return __io_sqe_files_scm(ctx, 1, index);
-#else
- return 0;
-#endif
-}
-
-static int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx,
- struct io_rsrc_node *node, void *rsrc)
-{
- struct io_rsrc_put *prsrc;
-
- prsrc = kzalloc(sizeof(*prsrc), GFP_KERNEL);
- if (!prsrc)
- return -ENOMEM;
-
- prsrc->tag = *io_get_tag_slot(data, idx);
- prsrc->rsrc = rsrc;
- list_add(&prsrc->list, &node->rsrc_list);
- return 0;
-}
-
-static int io_install_fixed_file(struct io_kiocb *req, struct file *file,
- unsigned int issue_flags, u32 slot_index)
-{
- struct io_ring_ctx *ctx = req->ctx;
- bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
- bool needs_switch = false;
- struct io_fixed_file *file_slot;
- int ret = -EBADF;
-
- io_ring_submit_lock(ctx, needs_lock);
- if (file->f_op == &io_uring_fops)
- goto err;
- ret = -ENXIO;
- if (!ctx->file_data)
- goto err;
- ret = -EINVAL;
- if (slot_index >= ctx->nr_user_files)
- goto err;
-
- slot_index = array_index_nospec(slot_index, ctx->nr_user_files);
- file_slot = io_fixed_file_slot(&ctx->file_table, slot_index);
-
- if (file_slot->file_ptr) {
- struct file *old_file;
-
- ret = io_rsrc_node_switch_start(ctx);
- if (ret)
- goto err;
-
- old_file = (struct file *)(file_slot->file_ptr & FFS_MASK);
- ret = io_queue_rsrc_removal(ctx->file_data, slot_index,
- ctx->rsrc_node, old_file);
- if (ret)
- goto err;
- file_slot->file_ptr = 0;
- needs_switch = true;
- }
-
- *io_get_tag_slot(ctx->file_data, slot_index) = 0;
- io_fixed_file_set(file_slot, file);
- ret = io_sqe_file_register(ctx, file, slot_index);
- if (ret) {
- file_slot->file_ptr = 0;
- goto err;
- }
-
- ret = 0;
-err:
- if (needs_switch)
- io_rsrc_node_switch(ctx, ctx->file_data);
- io_ring_submit_unlock(ctx, needs_lock);
- if (ret)
- fput(file);
- return ret;
-}
-
-static int io_close_fixed(struct io_kiocb *req, unsigned int issue_flags)
-{
- unsigned int offset = req->close.file_slot - 1;
- struct io_ring_ctx *ctx = req->ctx;
- bool needs_lock = issue_flags & IO_URING_F_UNLOCKED;
- struct io_fixed_file *file_slot;
- struct file *file;
- int ret, i;
-
- io_ring_submit_lock(ctx, needs_lock);
- ret = -ENXIO;
- if (unlikely(!ctx->file_data))
- goto out;
- ret = -EINVAL;
- if (offset >= ctx->nr_user_files)
- goto out;
- ret = io_rsrc_node_switch_start(ctx);
- if (ret)
- goto out;
-
- i = array_index_nospec(offset, ctx->nr_user_files);
- file_slot = io_fixed_file_slot(&ctx->file_table, i);
- ret = -EBADF;
- if (!file_slot->file_ptr)
- goto out;
-
- file = (struct file *)(file_slot->file_ptr & FFS_MASK);
- ret = io_queue_rsrc_removal(ctx->file_data, offset, ctx->rsrc_node, file);
- if (ret)
- goto out;
-
- file_slot->file_ptr = 0;
- io_rsrc_node_switch(ctx, ctx->file_data);
- ret = 0;
-out:
- io_ring_submit_unlock(ctx, needs_lock);
- return ret;
-}
-
-static int __io_sqe_files_update(struct io_ring_ctx *ctx,
- struct io_uring_rsrc_update2 *up,
- unsigned nr_args)
-{
- u64 __user *tags = u64_to_user_ptr(up->tags);
- __s32 __user *fds = u64_to_user_ptr(up->data);
- struct io_rsrc_data *data = ctx->file_data;
- struct io_fixed_file *file_slot;
- struct file *file;
- int fd, i, err = 0;
- unsigned int done;
- bool needs_switch = false;
-
- if (!ctx->file_data)
- return -ENXIO;
- if (up->offset + nr_args > ctx->nr_user_files)
- return -EINVAL;
-
- for (done = 0; done < nr_args; done++) {
- u64 tag = 0;
-
- if ((tags && copy_from_user(&tag, &tags[done], sizeof(tag))) ||
- copy_from_user(&fd, &fds[done], sizeof(fd))) {
- err = -EFAULT;
- break;
- }
- if ((fd == IORING_REGISTER_FILES_SKIP || fd == -1) && tag) {
- err = -EINVAL;
- break;
- }
- if (fd == IORING_REGISTER_FILES_SKIP)
- continue;
-
- i = array_index_nospec(up->offset + done, ctx->nr_user_files);
- file_slot = io_fixed_file_slot(&ctx->file_table, i);
-
- if (file_slot->file_ptr) {
- file = (struct file *)(file_slot->file_ptr & FFS_MASK);
- err = io_queue_rsrc_removal(data, up->offset + done,
- ctx->rsrc_node, file);
- if (err)
- break;
- file_slot->file_ptr = 0;
- needs_switch = true;
- }
- if (fd != -1) {
- file = fget(fd);
- if (!file) {
- err = -EBADF;
- break;
- }
- /*
- * Don't allow io_uring instances to be registered. If
- * UNIX isn't enabled, then this causes a reference
- * cycle and this instance can never get freed. If UNIX
- * is enabled we'll handle it just fine, but there's
- * still no point in allowing a ring fd as it doesn't
- * support regular read/write anyway.
- */
- if (file->f_op == &io_uring_fops) {
- fput(file);
- err = -EBADF;
- break;
- }
- *io_get_tag_slot(data, up->offset + done) = tag;
- io_fixed_file_set(file_slot, file);
- err = io_sqe_file_register(ctx, file, i);
- if (err) {
- file_slot->file_ptr = 0;
- fput(file);
- break;
- }
- }
- }
-
- if (needs_switch)
- io_rsrc_node_switch(ctx, data);
- return done ? done : err;
-}
-
-static struct io_wq *io_init_wq_offload(struct io_ring_ctx *ctx,
- struct task_struct *task)
-{
- struct io_wq_hash *hash;
- struct io_wq_data data;
- unsigned int concurrency;
-
- mutex_lock(&ctx->uring_lock);
- hash = ctx->hash_map;
- if (!hash) {
- hash = kzalloc(sizeof(*hash), GFP_KERNEL);
- if (!hash) {
- mutex_unlock(&ctx->uring_lock);
- return ERR_PTR(-ENOMEM);
- }
- refcount_set(&hash->refs, 1);
- init_waitqueue_head(&hash->wait);
- ctx->hash_map = hash;
- }
- mutex_unlock(&ctx->uring_lock);
-
- data.hash = hash;
- data.task = task;
- data.free_work = io_wq_free_work;
- data.do_work = io_wq_submit_work;
-
- /* Do QD, or 4 * CPUS, whatever is smallest */
- concurrency = min(ctx->sq_entries, 4 * num_online_cpus());
-
- return io_wq_create(concurrency, &data);
-}
-
-static __cold int io_uring_alloc_task_context(struct task_struct *task,
- struct io_ring_ctx *ctx)
-{
- struct io_uring_task *tctx;
- int ret;
-
- tctx = kzalloc(sizeof(*tctx), GFP_KERNEL);
- if (unlikely(!tctx))
- return -ENOMEM;
-
- ret = percpu_counter_init(&tctx->inflight, 0, GFP_KERNEL);
- if (unlikely(ret)) {
- kfree(tctx);
- return ret;
- }
-
- tctx->io_wq = io_init_wq_offload(ctx, task);
- if (IS_ERR(tctx->io_wq)) {
- ret = PTR_ERR(tctx->io_wq);
- percpu_counter_destroy(&tctx->inflight);
- kfree(tctx);
- return ret;
- }
-
- xa_init(&tctx->xa);
- init_waitqueue_head(&tctx->wait);
- atomic_set(&tctx->in_idle, 0);
- atomic_set(&tctx->inflight_tracked, 0);
- task->io_uring = tctx;
- spin_lock_init(&tctx->task_lock);
- INIT_WQ_LIST(&tctx->task_list);
- init_task_work(&tctx->task_work, tctx_task_work);
- return 0;
-}
-
-void __io_uring_free(struct task_struct *tsk)
-{
- struct io_uring_task *tctx = tsk->io_uring;
-
- WARN_ON_ONCE(!xa_empty(&tctx->xa));
- WARN_ON_ONCE(tctx->io_wq);
- WARN_ON_ONCE(tctx->cached_refs);
-
- percpu_counter_destroy(&tctx->inflight);
- kfree(tctx);
- tsk->io_uring = NULL;
-}
-
-static __cold int io_sq_offload_create(struct io_ring_ctx *ctx,
- struct io_uring_params *p)
-{
- int ret;
-
- /* Retain compatibility with failing for an invalid attach attempt */
- if ((ctx->flags & (IORING_SETUP_ATTACH_WQ | IORING_SETUP_SQPOLL)) ==
- IORING_SETUP_ATTACH_WQ) {
- struct fd f;
-
- f = fdget(p->wq_fd);
- if (!f.file)
- return -ENXIO;
- if (f.file->f_op != &io_uring_fops) {
- fdput(f);
- return -EINVAL;
- }
- fdput(f);
- }
- if (ctx->flags & IORING_SETUP_SQPOLL) {
- struct task_struct *tsk;
- struct io_sq_data *sqd;
- bool attached;
-
- ret = security_uring_sqpoll();
- if (ret)
- return ret;
-
- sqd = io_get_sq_data(p, &attached);
- if (IS_ERR(sqd)) {
- ret = PTR_ERR(sqd);
- goto err;
- }
-
- ctx->sq_creds = get_current_cred();
- ctx->sq_data = sqd;
- ctx->sq_thread_idle = msecs_to_jiffies(p->sq_thread_idle);
- if (!ctx->sq_thread_idle)
- ctx->sq_thread_idle = HZ;
-
- io_sq_thread_park(sqd);
- list_add(&ctx->sqd_list, &sqd->ctx_list);
- io_sqd_update_thread_idle(sqd);
- /* don't attach to a dying SQPOLL thread, would be racy */
- ret = (attached && !sqd->thread) ? -ENXIO : 0;
- io_sq_thread_unpark(sqd);
-
- if (ret < 0)
- goto err;
- if (attached)
- return 0;
-
- if (p->flags & IORING_SETUP_SQ_AFF) {
- int cpu = p->sq_thread_cpu;
-
- ret = -EINVAL;
- if (cpu >= nr_cpu_ids || !cpu_online(cpu))
- goto err_sqpoll;
- sqd->sq_cpu = cpu;
- } else {
- sqd->sq_cpu = -1;
- }
-
- sqd->task_pid = current->pid;
- sqd->task_tgid = current->tgid;
- tsk = create_io_thread(io_sq_thread, sqd, NUMA_NO_NODE);
- if (IS_ERR(tsk)) {
- ret = PTR_ERR(tsk);
- goto err_sqpoll;
- }
-
- sqd->thread = tsk;
- ret = io_uring_alloc_task_context(tsk, ctx);
- wake_up_new_task(tsk);
- if (ret)
- goto err;
- } else if (p->flags & IORING_SETUP_SQ_AFF) {
- /* Can't have SQ_AFF without SQPOLL */
- ret = -EINVAL;
- goto err;
- }
-
- return 0;
-err_sqpoll:
- complete(&ctx->sq_data->exited);
-err:
- io_sq_thread_finish(ctx);
- return ret;
-}
-
-static inline void __io_unaccount_mem(struct user_struct *user,
- unsigned long nr_pages)
-{
- atomic_long_sub(nr_pages, &user->locked_vm);
-}
-
-static inline int __io_account_mem(struct user_struct *user,
- unsigned long nr_pages)
-{
- unsigned long page_limit, cur_pages, new_pages;
-
- /* Don't allow more pages than we can safely lock */
- page_limit = rlimit(RLIMIT_MEMLOCK) >> PAGE_SHIFT;
-
- do {
- cur_pages = atomic_long_read(&user->locked_vm);
- new_pages = cur_pages + nr_pages;
- if (new_pages > page_limit)
- return -ENOMEM;
- } while (atomic_long_cmpxchg(&user->locked_vm, cur_pages,
- new_pages) != cur_pages);
-
- return 0;
-}
-
-static void io_unaccount_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
-{
- if (ctx->user)
- __io_unaccount_mem(ctx->user, nr_pages);
-
- if (ctx->mm_account)
- atomic64_sub(nr_pages, &ctx->mm_account->pinned_vm);
-}
-
-static int io_account_mem(struct io_ring_ctx *ctx, unsigned long nr_pages)
-{
- int ret;
-
- if (ctx->user) {
- ret = __io_account_mem(ctx->user, nr_pages);
- if (ret)
- return ret;
- }
-
- if (ctx->mm_account)
- atomic64_add(nr_pages, &ctx->mm_account->pinned_vm);
-
- return 0;
-}
-
-static void io_mem_free(void *ptr)
-{
- struct page *page;
-
- if (!ptr)
- return;
-
- page = virt_to_head_page(ptr);
- if (put_page_testzero(page))
- free_compound_page(page);
-}
-
-static void *io_mem_alloc(size_t size)
-{
- gfp_t gfp_flags = GFP_KERNEL | __GFP_ZERO | __GFP_NOWARN | __GFP_COMP |
- __GFP_NORETRY | __GFP_ACCOUNT;
-
- return (void *) __get_free_pages(gfp_flags, get_order(size));
-}
-
-static unsigned long rings_size(unsigned sq_entries, unsigned cq_entries,
- size_t *sq_offset)
-{
- struct io_rings *rings;
- size_t off, sq_array_size;
-
- off = struct_size(rings, cqes, cq_entries);
- if (off == SIZE_MAX)
- return SIZE_MAX;
-
-#ifdef CONFIG_SMP
- off = ALIGN(off, SMP_CACHE_BYTES);
- if (off == 0)
- return SIZE_MAX;
-#endif
-
- if (sq_offset)
- *sq_offset = off;
-
- sq_array_size = array_size(sizeof(u32), sq_entries);
- if (sq_array_size == SIZE_MAX)
- return SIZE_MAX;
-
- if (check_add_overflow(off, sq_array_size, &off))
- return SIZE_MAX;
-
- return off;
-}
-
-static void io_buffer_unmap(struct io_ring_ctx *ctx, struct io_mapped_ubuf **slot)
-{
- struct io_mapped_ubuf *imu = *slot;
- unsigned int i;
-
- if (imu != ctx->dummy_ubuf) {
- for (i = 0; i < imu->nr_bvecs; i++)
- unpin_user_page(imu->bvec[i].bv_page);
- if (imu->acct_pages)
- io_unaccount_mem(ctx, imu->acct_pages);
- kvfree(imu);
- }
- *slot = NULL;
-}
-
-static void io_rsrc_buf_put(struct io_ring_ctx *ctx, struct io_rsrc_put *prsrc)
-{
- io_buffer_unmap(ctx, &prsrc->buf);
- prsrc->buf = NULL;
-}
-
-static void __io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
-{
- unsigned int i;
-
- for (i = 0; i < ctx->nr_user_bufs; i++)
- io_buffer_unmap(ctx, &ctx->user_bufs[i]);
- kfree(ctx->user_bufs);
- io_rsrc_data_free(ctx->buf_data);
- ctx->user_bufs = NULL;
- ctx->buf_data = NULL;
- ctx->nr_user_bufs = 0;
-}
-
-static int io_sqe_buffers_unregister(struct io_ring_ctx *ctx)
-{
- int ret;
-
- if (!ctx->buf_data)
- return -ENXIO;
-
- ret = io_rsrc_ref_quiesce(ctx->buf_data, ctx);
- if (!ret)
- __io_sqe_buffers_unregister(ctx);
- return ret;
-}
-
-static int io_copy_iov(struct io_ring_ctx *ctx, struct iovec *dst,
- void __user *arg, unsigned index)
-{
- struct iovec __user *src;
-
-#ifdef CONFIG_COMPAT
- if (ctx->compat) {
- struct compat_iovec __user *ciovs;
- struct compat_iovec ciov;
-
- ciovs = (struct compat_iovec __user *) arg;
- if (copy_from_user(&ciov, &ciovs[index], sizeof(ciov)))
- return -EFAULT;
-
- dst->iov_base = u64_to_user_ptr((u64)ciov.iov_base);
- dst->iov_len = ciov.iov_len;
- return 0;
- }
-#endif
- src = (struct iovec __user *) arg;
- if (copy_from_user(dst, &src[index], sizeof(*dst)))
- return -EFAULT;
- return 0;
-}
-
-/*
- * Not super efficient, but this is just a registration time. And we do cache
- * the last compound head, so generally we'll only do a full search if we don't
- * match that one.
- *
- * We check if the given compound head page has already been accounted, to
- * avoid double accounting it. This allows us to account the full size of the
- * page, not just the constituent pages of a huge page.
- */
-static bool headpage_already_acct(struct io_ring_ctx *ctx, struct page **pages,
- int nr_pages, struct page *hpage)
-{
- int i, j;
-
- /* check current page array */
- for (i = 0; i < nr_pages; i++) {
- if (!PageCompound(pages[i]))
- continue;
- if (compound_head(pages[i]) == hpage)
- return true;
- }
-
- /* check previously registered pages */
- for (i = 0; i < ctx->nr_user_bufs; i++) {
- struct io_mapped_ubuf *imu = ctx->user_bufs[i];
-
- for (j = 0; j < imu->nr_bvecs; j++) {
- if (!PageCompound(imu->bvec[j].bv_page))
- continue;
- if (compound_head(imu->bvec[j].bv_page) == hpage)
- return true;
- }
- }
-
- return false;
-}
-
-static int io_buffer_account_pin(struct io_ring_ctx *ctx, struct page **pages,
- int nr_pages, struct io_mapped_ubuf *imu,
- struct page **last_hpage)
-{
- int i, ret;
-
- imu->acct_pages = 0;
- for (i = 0; i < nr_pages; i++) {
- if (!PageCompound(pages[i])) {
- imu->acct_pages++;
- } else {
- struct page *hpage;
-
- hpage = compound_head(pages[i]);
- if (hpage == *last_hpage)
- continue;
- *last_hpage = hpage;
- if (headpage_already_acct(ctx, pages, i, hpage))
- continue;
- imu->acct_pages += page_size(hpage) >> PAGE_SHIFT;
- }
- }
-
- if (!imu->acct_pages)
- return 0;
-
- ret = io_account_mem(ctx, imu->acct_pages);
- if (ret)
- imu->acct_pages = 0;
- return ret;
-}
-
-static int io_sqe_buffer_register(struct io_ring_ctx *ctx, struct iovec *iov,
- struct io_mapped_ubuf **pimu,
- struct page **last_hpage)
-{
- struct io_mapped_ubuf *imu = NULL;
- struct vm_area_struct **vmas = NULL;
- struct page **pages = NULL;
- unsigned long off, start, end, ubuf;
- size_t size;
- int ret, pret, nr_pages, i;
-
- if (!iov->iov_base) {
- *pimu = ctx->dummy_ubuf;
- return 0;
- }
-
- ubuf = (unsigned long) iov->iov_base;
- end = (ubuf + iov->iov_len + PAGE_SIZE - 1) >> PAGE_SHIFT;
- start = ubuf >> PAGE_SHIFT;
- nr_pages = end - start;
-
- *pimu = NULL;
- ret = -ENOMEM;
-
- pages = kvmalloc_array(nr_pages, sizeof(struct page *), GFP_KERNEL);
- if (!pages)
- goto done;
-
- vmas = kvmalloc_array(nr_pages, sizeof(struct vm_area_struct *),
- GFP_KERNEL);
- if (!vmas)
- goto done;
-
- imu = kvmalloc(struct_size(imu, bvec, nr_pages), GFP_KERNEL);
- if (!imu)
- goto done;
-
- ret = 0;
- mmap_read_lock(current->mm);
- pret = pin_user_pages(ubuf, nr_pages, FOLL_WRITE | FOLL_LONGTERM,
- pages, vmas);
- if (pret == nr_pages) {
- /* don't support file backed memory */
- for (i = 0; i < nr_pages; i++) {
- struct vm_area_struct *vma = vmas[i];
-
- if (vma_is_shmem(vma))
- continue;
- if (vma->vm_file &&
- !is_file_hugepages(vma->vm_file)) {
- ret = -EOPNOTSUPP;
- break;
- }
- }
- } else {
- ret = pret < 0 ? pret : -EFAULT;
- }
- mmap_read_unlock(current->mm);
- if (ret) {
- /*
- * if we did partial map, or found file backed vmas,
- * release any pages we did get
- */
- if (pret > 0)
- unpin_user_pages(pages, pret);
- goto done;
- }
-
- ret = io_buffer_account_pin(ctx, pages, pret, imu, last_hpage);
- if (ret) {
- unpin_user_pages(pages, pret);
- goto done;
- }
-
- off = ubuf & ~PAGE_MASK;
- size = iov->iov_len;
- for (i = 0; i < nr_pages; i++) {
- size_t vec_len;
-
- vec_len = min_t(size_t, size, PAGE_SIZE - off);
- imu->bvec[i].bv_page = pages[i];
- imu->bvec[i].bv_len = vec_len;
- imu->bvec[i].bv_offset = off;
- off = 0;
- size -= vec_len;
- }
- /* store original address for later verification */
- imu->ubuf = ubuf;
- imu->ubuf_end = ubuf + iov->iov_len;
- imu->nr_bvecs = nr_pages;
- *pimu = imu;
- ret = 0;
-done:
- if (ret)
- kvfree(imu);
- kvfree(pages);
- kvfree(vmas);
- return ret;
-}
-
-static int io_buffers_map_alloc(struct io_ring_ctx *ctx, unsigned int nr_args)
-{
- ctx->user_bufs = kcalloc(nr_args, sizeof(*ctx->user_bufs), GFP_KERNEL);
- return ctx->user_bufs ? 0 : -ENOMEM;
-}
-
-static int io_buffer_validate(struct iovec *iov)
-{
- unsigned long tmp, acct_len = iov->iov_len + (PAGE_SIZE - 1);
-
- /*
- * Don't impose further limits on the size and buffer
- * constraints here, we'll -EINVAL later when IO is
- * submitted if they are wrong.
- */
- if (!iov->iov_base)
- return iov->iov_len ? -EFAULT : 0;
- if (!iov->iov_len)
- return -EFAULT;
-
- /* arbitrary limit, but we need something */
- if (iov->iov_len > SZ_1G)
- return -EFAULT;
-
- if (check_add_overflow((unsigned long)iov->iov_base, acct_len, &tmp))
- return -EOVERFLOW;
-
- return 0;
-}
-
-static int io_sqe_buffers_register(struct io_ring_ctx *ctx, void __user *arg,
- unsigned int nr_args, u64 __user *tags)
-{
- struct page *last_hpage = NULL;
- struct io_rsrc_data *data;
- int i, ret;
- struct iovec iov;
-
- if (ctx->user_bufs)
- return -EBUSY;
- if (!nr_args || nr_args > IORING_MAX_REG_BUFFERS)
- return -EINVAL;
- ret = io_rsrc_node_switch_start(ctx);
- if (ret)
- return ret;
- ret = io_rsrc_data_alloc(ctx, io_rsrc_buf_put, tags, nr_args, &data);
- if (ret)
- return ret;
- ret = io_buffers_map_alloc(ctx, nr_args);
- if (ret) {
- io_rsrc_data_free(data);
- return ret;
- }
-
- for (i = 0; i < nr_args; i++, ctx->nr_user_bufs++) {
- ret = io_copy_iov(ctx, &iov, arg, i);
- if (ret)
- break;
- ret = io_buffer_validate(&iov);
- if (ret)
- break;
- if (!iov.iov_base && *io_get_tag_slot(data, i)) {
- ret = -EINVAL;
- break;
- }
-
- ret = io_sqe_buffer_register(ctx, &iov, &ctx->user_bufs[i],
- &last_hpage);
- if (ret)
- break;
- }
-
- WARN_ON_ONCE(ctx->buf_data);
-
- ctx->buf_data = data;
- if (ret)
- __io_sqe_buffers_unregister(ctx);
- else
- io_rsrc_node_switch(ctx, NULL);
- return ret;
-}
-
-static int __io_sqe_buffers_update(struct io_ring_ctx *ctx,
- struct io_uring_rsrc_update2 *up,
- unsigned int nr_args)
-{
- u64 __user *tags = u64_to_user_ptr(up->tags);
- struct iovec iov, __user *iovs = u64_to_user_ptr(up->data);
- struct page *last_hpage = NULL;
- bool needs_switch = false;
- __u32 done;
- int i, err;
-
- if (!ctx->buf_data)
- return -ENXIO;
- if (up->offset + nr_args > ctx->nr_user_bufs)
- return -EINVAL;
-
- for (done = 0; done < nr_args; done++) {
- struct io_mapped_ubuf *imu;
- int offset = up->offset + done;
- u64 tag = 0;
-
- err = io_copy_iov(ctx, &iov, iovs, done);
- if (err)
- break;
- if (tags && copy_from_user(&tag, &tags[done], sizeof(tag))) {
- err = -EFAULT;
- break;
- }
- err = io_buffer_validate(&iov);
- if (err)
- break;
- if (!iov.iov_base && tag) {
- err = -EINVAL;
- break;
- }
- err = io_sqe_buffer_register(ctx, &iov, &imu, &last_hpage);
- if (err)
- break;
-
- i = array_index_nospec(offset, ctx->nr_user_bufs);
- if (ctx->user_bufs[i] != ctx->dummy_ubuf) {
- err = io_queue_rsrc_removal(ctx->buf_data, offset,
- ctx->rsrc_node, ctx->user_bufs[i]);
- if (unlikely(err)) {
- io_buffer_unmap(ctx, &imu);
- break;
- }
- ctx->user_bufs[i] = NULL;
- needs_switch = true;
- }
-
- ctx->user_bufs[i] = imu;
- *io_get_tag_slot(ctx->buf_data, offset) = tag;
- }
-
- if (needs_switch)
- io_rsrc_node_switch(ctx, ctx->buf_data);
- return done ? done : err;
-}
-
-static int io_eventfd_register(struct io_ring_ctx *ctx, void __user *arg)
-{
- __s32 __user *fds = arg;
- int fd;
-
- if (ctx->cq_ev_fd)
- return -EBUSY;
-
- if (copy_from_user(&fd, fds, sizeof(*fds)))
- return -EFAULT;
-
- ctx->cq_ev_fd = eventfd_ctx_fdget(fd);
- if (IS_ERR(ctx->cq_ev_fd)) {
- int ret = PTR_ERR(ctx->cq_ev_fd);
-
- ctx->cq_ev_fd = NULL;
- return ret;
- }
-
- return 0;
-}
-
-static int io_eventfd_unregister(struct io_ring_ctx *ctx)
-{
- if (ctx->cq_ev_fd) {
- eventfd_ctx_put(ctx->cq_ev_fd);
- ctx->cq_ev_fd = NULL;
- return 0;
- }
-
- return -ENXIO;
-}
-
-static void io_destroy_buffers(struct io_ring_ctx *ctx)
-{
- struct io_buffer *buf;
- unsigned long index;
-
- xa_for_each(&ctx->io_buffers, index, buf)
- __io_remove_buffers(ctx, buf, index, -1U);
-}
-
-static void io_req_caches_free(struct io_ring_ctx *ctx)
-{
- struct io_submit_state *state = &ctx->submit_state;
- int nr = 0;
-
- mutex_lock(&ctx->uring_lock);
- io_flush_cached_locked_reqs(ctx, state);
-
- while (state->free_list.next) {
- struct io_wq_work_node *node;
- struct io_kiocb *req;
-
- node = wq_stack_extract(&state->free_list);
- req = container_of(node, struct io_kiocb, comp_list);
- kmem_cache_free(req_cachep, req);
- nr++;
- }
- if (nr)
- percpu_ref_put_many(&ctx->refs, nr);
- mutex_unlock(&ctx->uring_lock);
-}
-
-static void io_wait_rsrc_data(struct io_rsrc_data *data)
-{
- if (data && !atomic_dec_and_test(&data->refs))
- wait_for_completion(&data->done);
-}
-
-static __cold void io_ring_ctx_free(struct io_ring_ctx *ctx)
-{
- io_sq_thread_finish(ctx);
-
- if (ctx->mm_account) {
- mmdrop(ctx->mm_account);
- ctx->mm_account = NULL;
- }
-
- io_rsrc_refs_drop(ctx);
- /* __io_rsrc_put_work() may need uring_lock to progress, wait w/o it */
- io_wait_rsrc_data(ctx->buf_data);
- io_wait_rsrc_data(ctx->file_data);
-
- mutex_lock(&ctx->uring_lock);
- if (ctx->buf_data)
- __io_sqe_buffers_unregister(ctx);
- if (ctx->file_data)
- __io_sqe_files_unregister(ctx);
- if (ctx->rings)
- __io_cqring_overflow_flush(ctx, true);
- mutex_unlock(&ctx->uring_lock);
- io_eventfd_unregister(ctx);
- io_destroy_buffers(ctx);
- if (ctx->sq_creds)
- put_cred(ctx->sq_creds);
-
- /* there are no registered resources left, nobody uses it */
- if (ctx->rsrc_node)
- io_rsrc_node_destroy(ctx->rsrc_node);
- if (ctx->rsrc_backup_node)
- io_rsrc_node_destroy(ctx->rsrc_backup_node);
- flush_delayed_work(&ctx->rsrc_put_work);
- flush_delayed_work(&ctx->fallback_work);
-
- WARN_ON_ONCE(!list_empty(&ctx->rsrc_ref_list));
- WARN_ON_ONCE(!llist_empty(&ctx->rsrc_put_llist));
-
-#if defined(CONFIG_UNIX)
- if (ctx->ring_sock) {
- ctx->ring_sock->file = NULL; /* so that iput() is called */
- sock_release(ctx->ring_sock);
- }
-#endif
- WARN_ON_ONCE(!list_empty(&ctx->ltimeout_list));
-
- io_mem_free(ctx->rings);
- io_mem_free(ctx->sq_sqes);
-
- percpu_ref_exit(&ctx->refs);
- free_uid(ctx->user);
- io_req_caches_free(ctx);
- if (ctx->hash_map)
- io_wq_put_hash(ctx->hash_map);
- kfree(ctx->cancel_hash);
- kfree(ctx->dummy_ubuf);
- kfree(ctx);
-}
-
-static __poll_t io_uring_poll(struct file *file, poll_table *wait)
-{
- struct io_ring_ctx *ctx = file->private_data;
- __poll_t mask = 0;
-
- poll_wait(file, &ctx->cq_wait, wait);
- /*
- * synchronizes with barrier from wq_has_sleeper call in
- * io_commit_cqring
- */
- smp_rmb();
- if (!io_sqring_full(ctx))
- mask |= EPOLLOUT | EPOLLWRNORM;
-
- /*
- * Don't flush cqring overflow list here, just do a simple check.
- * Otherwise there could possible be ABBA deadlock:
- * CPU0 CPU1
- * ---- ----
- * lock(&ctx->uring_lock);
- * lock(&ep->mtx);
- * lock(&ctx->uring_lock);
- * lock(&ep->mtx);
- *
- * Users may get EPOLLIN meanwhile seeing nothing in cqring, this
- * pushs them to do the flush.
- */
- if (io_cqring_events(ctx) || test_bit(0, &ctx->check_cq_overflow))
- mask |= EPOLLIN | EPOLLRDNORM;
-
- return mask;
-}
-
-static int io_unregister_personality(struct io_ring_ctx *ctx, unsigned id)
-{
- const struct cred *creds;
-
- creds = xa_erase(&ctx->personalities, id);
- if (creds) {
- put_cred(creds);
- return 0;
- }
-
- return -EINVAL;
-}
-
-struct io_tctx_exit {
- struct callback_head task_work;
- struct completion completion;
- struct io_ring_ctx *ctx;
-};
-
-static __cold void io_tctx_exit_cb(struct callback_head *cb)
-{
- struct io_uring_task *tctx = current->io_uring;
- struct io_tctx_exit *work;
-
- work = container_of(cb, struct io_tctx_exit, task_work);
- /*
- * When @in_idle, we're in cancellation and it's racy to remove the
- * node. It'll be removed by the end of cancellation, just ignore it.
- */
- if (!atomic_read(&tctx->in_idle))
- io_uring_del_tctx_node((unsigned long)work->ctx);
- complete(&work->completion);
-}
-
-static __cold bool io_cancel_ctx_cb(struct io_wq_work *work, void *data)
-{
- struct io_kiocb *req = container_of(work, struct io_kiocb, work);
-
- return req->ctx == data;
-}
-
-static __cold void io_ring_exit_work(struct work_struct *work)
-{
- struct io_ring_ctx *ctx = container_of(work, struct io_ring_ctx, exit_work);
- unsigned long timeout = jiffies + HZ * 60 * 5;
- unsigned long interval = HZ / 20;
- struct io_tctx_exit exit;
- struct io_tctx_node *node;
- int ret;
-
- /*
- * If we're doing polled IO and end up having requests being
- * submitted async (out-of-line), then completions can come in while
- * we're waiting for refs to drop. We need to reap these manually,
- * as nobody else will be looking for them.
- */
- do {
- io_uring_try_cancel_requests(ctx, NULL, true);
- if (ctx->sq_data) {
- struct io_sq_data *sqd = ctx->sq_data;
- struct task_struct *tsk;
-
- io_sq_thread_park(sqd);
- tsk = sqd->thread;
- if (tsk && tsk->io_uring && tsk->io_uring->io_wq)
- io_wq_cancel_cb(tsk->io_uring->io_wq,
- io_cancel_ctx_cb, ctx, true);
- io_sq_thread_unpark(sqd);
- }
-
- io_req_caches_free(ctx);
-
- if (WARN_ON_ONCE(time_after(jiffies, timeout))) {
- /* there is little hope left, don't run it too often */
- interval = HZ * 60;
- }
- } while (!wait_for_completion_timeout(&ctx->ref_comp, interval));
-
- init_completion(&exit.completion);
- init_task_work(&exit.task_work, io_tctx_exit_cb);
- exit.ctx = ctx;
- /*
- * Some may use context even when all refs and requests have been put,
- * and they are free to do so while still holding uring_lock or
- * completion_lock, see io_req_task_submit(). Apart from other work,
- * this lock/unlock section also waits them to finish.
- */
- mutex_lock(&ctx->uring_lock);
- while (!list_empty(&ctx->tctx_list)) {
- WARN_ON_ONCE(time_after(jiffies, timeout));
-
- node = list_first_entry(&ctx->tctx_list, struct io_tctx_node,
- ctx_node);
- /* don't spin on a single task if cancellation failed */
- list_rotate_left(&ctx->tctx_list);
- ret = task_work_add(node->task, &exit.task_work, TWA_SIGNAL);
- if (WARN_ON_ONCE(ret))
- continue;
-
- mutex_unlock(&ctx->uring_lock);
- wait_for_completion(&exit.completion);
- mutex_lock(&ctx->uring_lock);
- }
- mutex_unlock(&ctx->uring_lock);
- spin_lock(&ctx->completion_lock);
- spin_unlock(&ctx->completion_lock);
-
- io_ring_ctx_free(ctx);
-}
-
-/* Returns true if we found and killed one or more timeouts */
-static __cold bool io_kill_timeouts(struct io_ring_ctx *ctx,
- struct task_struct *tsk, bool cancel_all)
-{
- struct io_kiocb *req, *tmp;
- int canceled = 0;
-
- spin_lock(&ctx->completion_lock);
- spin_lock_irq(&ctx->timeout_lock);
- list_for_each_entry_safe(req, tmp, &ctx->timeout_list, timeout.list) {
- if (io_match_task(req, tsk, cancel_all)) {
- io_kill_timeout(req, -ECANCELED);
- canceled++;
- }
- }
- spin_unlock_irq(&ctx->timeout_lock);
- if (canceled != 0)
- io_commit_cqring(ctx);
- spin_unlock(&ctx->completion_lock);
- if (canceled != 0)
- io_cqring_ev_posted(ctx);
- return canceled != 0;
-}
-
-static __cold void io_ring_ctx_wait_and_kill(struct io_ring_ctx *ctx)
-{
- unsigned long index;
- struct creds *creds;
-
- mutex_lock(&ctx->uring_lock);
- percpu_ref_kill(&ctx->refs);
- if (ctx->rings)
- __io_cqring_overflow_flush(ctx, true);
- xa_for_each(&ctx->personalities, index, creds)
- io_unregister_personality(ctx, index);
- mutex_unlock(&ctx->uring_lock);
-
- io_kill_timeouts(ctx, NULL, true);
- io_poll_remove_all(ctx, NULL, true);
-
- /* if we failed setting up the ctx, we might not have any rings */
- io_iopoll_try_reap_events(ctx);
-
- INIT_WORK(&ctx->exit_work, io_ring_exit_work);
- /*
- * Use system_unbound_wq to avoid spawning tons of event kworkers
- * if we're exiting a ton of rings at the same time. It just adds
- * noise and overhead, there's no discernable change in runtime
- * over using system_wq.
- */
- queue_work(system_unbound_wq, &ctx->exit_work);
-}
-
-static int io_uring_release(struct inode *inode, struct file *file)
-{
- struct io_ring_ctx *ctx = file->private_data;
-
- file->private_data = NULL;
- io_ring_ctx_wait_and_kill(ctx);
- return 0;
-}
-
-struct io_task_cancel {
- struct task_struct *task;
- bool all;
-};
-
-static bool io_cancel_task_cb(struct io_wq_work *work, void *data)
-{
- struct io_kiocb *req = container_of(work, struct io_kiocb, work);
- struct io_task_cancel *cancel = data;
-
- return io_match_task_safe(req, cancel->task, cancel->all);
-}
-
-static __cold bool io_cancel_defer_files(struct io_ring_ctx *ctx,
- struct task_struct *task,
- bool cancel_all)
-{
- struct io_defer_entry *de;
- LIST_HEAD(list);
-
- spin_lock(&ctx->completion_lock);
- list_for_each_entry_reverse(de, &ctx->defer_list, list) {
- if (io_match_task_safe(de->req, task, cancel_all)) {
- list_cut_position(&list, &ctx->defer_list, &de->list);
- break;
- }
- }
- spin_unlock(&ctx->completion_lock);
- if (list_empty(&list))
- return false;
-
- while (!list_empty(&list)) {
- de = list_first_entry(&list, struct io_defer_entry, list);
- list_del_init(&de->list);
- io_req_complete_failed(de->req, -ECANCELED);
- kfree(de);
- }
- return true;
-}
-
-static __cold bool io_uring_try_cancel_iowq(struct io_ring_ctx *ctx)
-{
- struct io_tctx_node *node;
- enum io_wq_cancel cret;
- bool ret = false;
-
- mutex_lock(&ctx->uring_lock);
- list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
- struct io_uring_task *tctx = node->task->io_uring;
-
- /*
- * io_wq will stay alive while we hold uring_lock, because it's
- * killed after ctx nodes, which requires to take the lock.
- */
- if (!tctx || !tctx->io_wq)
- continue;
- cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_ctx_cb, ctx, true);
- ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
- }
- mutex_unlock(&ctx->uring_lock);
-
- return ret;
-}
-
-static __cold void io_uring_try_cancel_requests(struct io_ring_ctx *ctx,
- struct task_struct *task,
- bool cancel_all)
-{
- struct io_task_cancel cancel = { .task = task, .all = cancel_all, };
- struct io_uring_task *tctx = task ? task->io_uring : NULL;
-
- while (1) {
- enum io_wq_cancel cret;
- bool ret = false;
-
- if (!task) {
- ret |= io_uring_try_cancel_iowq(ctx);
- } else if (tctx && tctx->io_wq) {
- /*
- * Cancels requests of all rings, not only @ctx, but
- * it's fine as the task is in exit/exec.
- */
- cret = io_wq_cancel_cb(tctx->io_wq, io_cancel_task_cb,
- &cancel, true);
- ret |= (cret != IO_WQ_CANCEL_NOTFOUND);
- }
-
- /* SQPOLL thread does its own polling */
- if ((!(ctx->flags & IORING_SETUP_SQPOLL) && cancel_all) ||
- (ctx->sq_data && ctx->sq_data->thread == current)) {
- while (!wq_list_empty(&ctx->iopoll_list)) {
- io_iopoll_try_reap_events(ctx);
- ret = true;
- }
- }
-
- ret |= io_cancel_defer_files(ctx, task, cancel_all);
- ret |= io_poll_remove_all(ctx, task, cancel_all);
- ret |= io_kill_timeouts(ctx, task, cancel_all);
- if (task)
- ret |= io_run_task_work();
- if (!ret)
- break;
- cond_resched();
- }
-}
-
-static int __io_uring_add_tctx_node(struct io_ring_ctx *ctx)
-{
- struct io_uring_task *tctx = current->io_uring;
- struct io_tctx_node *node;
- int ret;
-
- if (unlikely(!tctx)) {
- ret = io_uring_alloc_task_context(current, ctx);
- if (unlikely(ret))
- return ret;
-
- tctx = current->io_uring;
- if (ctx->iowq_limits_set) {
- unsigned int limits[2] = { ctx->iowq_limits[0],
- ctx->iowq_limits[1], };
-
- ret = io_wq_max_workers(tctx->io_wq, limits);
- if (ret)
- return ret;
- }
- }
- if (!xa_load(&tctx->xa, (unsigned long)ctx)) {
- node = kmalloc(sizeof(*node), GFP_KERNEL);
- if (!node)
- return -ENOMEM;
- node->ctx = ctx;
- node->task = current;
-
- ret = xa_err(xa_store(&tctx->xa, (unsigned long)ctx,
- node, GFP_KERNEL));
- if (ret) {
- kfree(node);
- return ret;
- }
-
- mutex_lock(&ctx->uring_lock);
- list_add(&node->ctx_node, &ctx->tctx_list);
- mutex_unlock(&ctx->uring_lock);
- }
- tctx->last = ctx;
- return 0;
-}
-
-/*
- * Note that this task has used io_uring. We use it for cancelation purposes.
- */
-static inline int io_uring_add_tctx_node(struct io_ring_ctx *ctx)
-{
- struct io_uring_task *tctx = current->io_uring;
-
- if (likely(tctx && tctx->last == ctx))
- return 0;
- return __io_uring_add_tctx_node(ctx);
-}
-
-/*
- * Remove this io_uring_file -> task mapping.
- */
-static __cold void io_uring_del_tctx_node(unsigned long index)
-{
- struct io_uring_task *tctx = current->io_uring;
- struct io_tctx_node *node;
-
- if (!tctx)
- return;
- node = xa_erase(&tctx->xa, index);
- if (!node)
- return;
-
- WARN_ON_ONCE(current != node->task);
- WARN_ON_ONCE(list_empty(&node->ctx_node));
-
- mutex_lock(&node->ctx->uring_lock);
- list_del(&node->ctx_node);
- mutex_unlock(&node->ctx->uring_lock);
-
- if (tctx->last == node->ctx)
- tctx->last = NULL;
- kfree(node);
-}
-
-static __cold void io_uring_clean_tctx(struct io_uring_task *tctx)
-{
- struct io_wq *wq = tctx->io_wq;
- struct io_tctx_node *node;
- unsigned long index;
-
- xa_for_each(&tctx->xa, index, node) {
- io_uring_del_tctx_node(index);
- cond_resched();
- }
- if (wq) {
- /*
- * Must be after io_uring_del_tctx_node() (removes nodes under
- * uring_lock) to avoid race with io_uring_try_cancel_iowq().
- */
- io_wq_put_and_exit(wq);
- tctx->io_wq = NULL;
- }
-}
-
-static s64 tctx_inflight(struct io_uring_task *tctx, bool tracked)
-{
- if (tracked)
- return atomic_read(&tctx->inflight_tracked);
- return percpu_counter_sum(&tctx->inflight);
-}
-
-static __cold void io_uring_drop_tctx_refs(struct task_struct *task)
-{
- struct io_uring_task *tctx = task->io_uring;
- unsigned int refs = tctx->cached_refs;
-
- if (refs) {
- tctx->cached_refs = 0;
- percpu_counter_sub(&tctx->inflight, refs);
- put_task_struct_many(task, refs);
- }
-}
-
-/*
- * Find any io_uring ctx that this task has registered or done IO on, and cancel
- * requests. @sqd should be not-null IFF it's an SQPOLL thread cancellation.
- */
-static __cold void io_uring_cancel_generic(bool cancel_all,
- struct io_sq_data *sqd)
-{
- struct io_uring_task *tctx = current->io_uring;
- struct io_ring_ctx *ctx;
- s64 inflight;
- DEFINE_WAIT(wait);
-
- WARN_ON_ONCE(sqd && sqd->thread != current);
-
- if (!current->io_uring)
- return;
- if (tctx->io_wq)
- io_wq_exit_start(tctx->io_wq);
-
- atomic_inc(&tctx->in_idle);
- do {
- io_uring_drop_tctx_refs(current);
- /* read completions before cancelations */
- inflight = tctx_inflight(tctx, !cancel_all);
- if (!inflight)
- break;
-
- if (!sqd) {
- struct io_tctx_node *node;
- unsigned long index;
-
- xa_for_each(&tctx->xa, index, node) {
- /* sqpoll task will cancel all its requests */
- if (node->ctx->sq_data)
- continue;
- io_uring_try_cancel_requests(node->ctx, current,
- cancel_all);
- }
- } else {
- list_for_each_entry(ctx, &sqd->ctx_list, sqd_list)
- io_uring_try_cancel_requests(ctx, current,
- cancel_all);
- }
-
- prepare_to_wait(&tctx->wait, &wait, TASK_INTERRUPTIBLE);
- io_run_task_work();
- io_uring_drop_tctx_refs(current);
-
- /*
- * If we've seen completions, retry without waiting. This
- * avoids a race where a completion comes in before we did
- * prepare_to_wait().
- */
- if (inflight == tctx_inflight(tctx, !cancel_all))
- schedule();
- finish_wait(&tctx->wait, &wait);
- } while (1);
- atomic_dec(&tctx->in_idle);
-
- io_uring_clean_tctx(tctx);
- if (cancel_all) {
- /* for exec all current's requests should be gone, kill tctx */
- __io_uring_free(current);
- }
-}
-
-void __io_uring_cancel(bool cancel_all)
-{
- io_uring_cancel_generic(cancel_all, NULL);
-}
-
-static void *io_uring_validate_mmap_request(struct file *file,
- loff_t pgoff, size_t sz)
-{
- struct io_ring_ctx *ctx = file->private_data;
- loff_t offset = pgoff << PAGE_SHIFT;
- struct page *page;
- void *ptr;
-
- switch (offset) {
- case IORING_OFF_SQ_RING:
- case IORING_OFF_CQ_RING:
- ptr = ctx->rings;
- break;
- case IORING_OFF_SQES:
- ptr = ctx->sq_sqes;
- break;
- default:
- return ERR_PTR(-EINVAL);
- }
-
- page = virt_to_head_page(ptr);
- if (sz > page_size(page))
- return ERR_PTR(-EINVAL);
-
- return ptr;
-}
-
-#ifdef CONFIG_MMU
-
-static __cold int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
-{
- size_t sz = vma->vm_end - vma->vm_start;
- unsigned long pfn;
- void *ptr;
-
- ptr = io_uring_validate_mmap_request(file, vma->vm_pgoff, sz);
- if (IS_ERR(ptr))
- return PTR_ERR(ptr);
-
- pfn = virt_to_phys(ptr) >> PAGE_SHIFT;
- return remap_pfn_range(vma, vma->vm_start, pfn, sz, vma->vm_page_prot);
-}
-
-#else /* !CONFIG_MMU */
-
-static int io_uring_mmap(struct file *file, struct vm_area_struct *vma)
-{
- return vma->vm_flags & (VM_SHARED | VM_MAYSHARE) ? 0 : -EINVAL;
-}
-
-static unsigned int io_uring_nommu_mmap_capabilities(struct file *file)
-{
- return NOMMU_MAP_DIRECT | NOMMU_MAP_READ | NOMMU_MAP_WRITE;
-}
-
-static unsigned long io_uring_nommu_get_unmapped_area(struct file *file,
- unsigned long addr, unsigned long len,
- unsigned long pgoff, unsigned long flags)
-{
- void *ptr;
-
- ptr = io_uring_validate_mmap_request(file, pgoff, len);
- if (IS_ERR(ptr))
- return PTR_ERR(ptr);
-
- return (unsigned long) ptr;
-}
-
-#endif /* !CONFIG_MMU */
-
-static int io_sqpoll_wait_sq(struct io_ring_ctx *ctx)
-{
- DEFINE_WAIT(wait);
-
- do {
- if (!io_sqring_full(ctx))
- break;
- prepare_to_wait(&ctx->sqo_sq_wait, &wait, TASK_INTERRUPTIBLE);
-
- if (!io_sqring_full(ctx))
- break;
- schedule();
- } while (!signal_pending(current));
-
- finish_wait(&ctx->sqo_sq_wait, &wait);
- return 0;
-}
-
-static int io_get_ext_arg(unsigned flags, const void __user *argp, size_t *argsz,
- struct __kernel_timespec __user **ts,
- const sigset_t __user **sig)
-{
- struct io_uring_getevents_arg arg;
-
- /*
- * If EXT_ARG isn't set, then we have no timespec and the argp pointer
- * is just a pointer to the sigset_t.
- */
- if (!(flags & IORING_ENTER_EXT_ARG)) {
- *sig = (const sigset_t __user *) argp;
- *ts = NULL;
- return 0;
- }
-
- /*
- * EXT_ARG is set - ensure we agree on the size of it and copy in our
- * timespec and sigset_t pointers if good.
- */
- if (*argsz != sizeof(arg))
- return -EINVAL;
- if (copy_from_user(&arg, argp, sizeof(arg)))
- return -EFAULT;
- *sig = u64_to_user_ptr(arg.sigmask);
- *argsz = arg.sigmask_sz;
- *ts = u64_to_user_ptr(arg.ts);
- return 0;
-}
-
-SYSCALL_DEFINE6(io_uring_enter, unsigned int, fd, u32, to_submit,
- u32, min_complete, u32, flags, const void __user *, argp,
- size_t, argsz)
-{
- struct io_ring_ctx *ctx;
- int submitted = 0;
- struct fd f;
- long ret;
-
- io_run_task_work();
-
- if (unlikely(flags & ~(IORING_ENTER_GETEVENTS | IORING_ENTER_SQ_WAKEUP |
- IORING_ENTER_SQ_WAIT | IORING_ENTER_EXT_ARG)))
- return -EINVAL;
-
- f = fdget(fd);
- if (unlikely(!f.file))
- return -EBADF;
-
- ret = -EOPNOTSUPP;
- if (unlikely(f.file->f_op != &io_uring_fops))
- goto out_fput;
-
- ret = -ENXIO;
- ctx = f.file->private_data;
- if (unlikely(!percpu_ref_tryget(&ctx->refs)))
- goto out_fput;
-
- ret = -EBADFD;
- if (unlikely(ctx->flags & IORING_SETUP_R_DISABLED))
- goto out;
-
- /*
- * For SQ polling, the thread will do all submissions and completions.
- * Just return the requested submit count, and wake the thread if
- * we were asked to.
- */
- ret = 0;
- if (ctx->flags & IORING_SETUP_SQPOLL) {
- io_cqring_overflow_flush(ctx);
-
- if (unlikely(ctx->sq_data->thread == NULL)) {
- ret = -EOWNERDEAD;
- goto out;
- }
- if (flags & IORING_ENTER_SQ_WAKEUP)
- wake_up(&ctx->sq_data->wait);
- if (flags & IORING_ENTER_SQ_WAIT) {
- ret = io_sqpoll_wait_sq(ctx);
- if (ret)
- goto out;
- }
- submitted = to_submit;
- } else if (to_submit) {
- ret = io_uring_add_tctx_node(ctx);
- if (unlikely(ret))
- goto out;
- mutex_lock(&ctx->uring_lock);
- submitted = io_submit_sqes(ctx, to_submit);
- mutex_unlock(&ctx->uring_lock);
-
- if (submitted != to_submit)
- goto out;
- }
- if (flags & IORING_ENTER_GETEVENTS) {
- const sigset_t __user *sig;
- struct __kernel_timespec __user *ts;
-
- ret = io_get_ext_arg(flags, argp, &argsz, &ts, &sig);
- if (unlikely(ret))
- goto out;
-
- min_complete = min(min_complete, ctx->cq_entries);
-
- /*
- * When SETUP_IOPOLL and SETUP_SQPOLL are both enabled, user
- * space applications don't need to do io completion events
- * polling again, they can rely on io_sq_thread to do polling
- * work, which can reduce cpu usage and uring_lock contention.
- */
- if (ctx->flags & IORING_SETUP_IOPOLL &&
- !(ctx->flags & IORING_SETUP_SQPOLL)) {
- ret = io_iopoll_check(ctx, min_complete);
- } else {
- ret = io_cqring_wait(ctx, min_complete, sig, argsz, ts);
- }
- }
-
-out:
- percpu_ref_put(&ctx->refs);
-out_fput:
- fdput(f);
- return submitted ? submitted : ret;
-}
-
-#ifdef CONFIG_PROC_FS
-static __cold int io_uring_show_cred(struct seq_file *m, unsigned int id,
- const struct cred *cred)
-{
- struct user_namespace *uns = seq_user_ns(m);
- struct group_info *gi;
- kernel_cap_t cap;
- unsigned __capi;
- int g;
-
- seq_printf(m, "%5d\n", id);
- seq_put_decimal_ull(m, "\tUid:\t", from_kuid_munged(uns, cred->uid));
- seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->euid));
- seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->suid));
- seq_put_decimal_ull(m, "\t\t", from_kuid_munged(uns, cred->fsuid));
- seq_put_decimal_ull(m, "\n\tGid:\t", from_kgid_munged(uns, cred->gid));
- seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->egid));
- seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->sgid));
- seq_put_decimal_ull(m, "\t\t", from_kgid_munged(uns, cred->fsgid));
- seq_puts(m, "\n\tGroups:\t");
- gi = cred->group_info;
- for (g = 0; g < gi->ngroups; g++) {
- seq_put_decimal_ull(m, g ? " " : "",
- from_kgid_munged(uns, gi->gid[g]));
- }
- seq_puts(m, "\n\tCapEff:\t");
- cap = cred->cap_effective;
- CAP_FOR_EACH_U32(__capi)
- seq_put_hex_ll(m, NULL, cap.cap[CAP_LAST_U32 - __capi], 8);
- seq_putc(m, '\n');
- return 0;
-}
-
-static __cold void __io_uring_show_fdinfo(struct io_ring_ctx *ctx,
- struct seq_file *m)
-{
- struct io_sq_data *sq = NULL;
- struct io_overflow_cqe *ocqe;
- struct io_rings *r = ctx->rings;
- unsigned int sq_mask = ctx->sq_entries - 1, cq_mask = ctx->cq_entries - 1;
- unsigned int sq_head = READ_ONCE(r->sq.head);
- unsigned int sq_tail = READ_ONCE(r->sq.tail);
- unsigned int cq_head = READ_ONCE(r->cq.head);
- unsigned int cq_tail = READ_ONCE(r->cq.tail);
- unsigned int sq_entries, cq_entries;
- bool has_lock;
- unsigned int i;
-
- /*
- * we may get imprecise sqe and cqe info if uring is actively running
- * since we get cached_sq_head and cached_cq_tail without uring_lock
- * and sq_tail and cq_head are changed by userspace. But it's ok since
- * we usually use these info when it is stuck.
- */
- seq_printf(m, "SqMask:\t\t0x%x\n", sq_mask);
- seq_printf(m, "SqHead:\t%u\n", sq_head);
- seq_printf(m, "SqTail:\t%u\n", sq_tail);
- seq_printf(m, "CachedSqHead:\t%u\n", ctx->cached_sq_head);
- seq_printf(m, "CqMask:\t0x%x\n", cq_mask);
- seq_printf(m, "CqHead:\t%u\n", cq_head);
- seq_printf(m, "CqTail:\t%u\n", cq_tail);
- seq_printf(m, "CachedCqTail:\t%u\n", ctx->cached_cq_tail);
- seq_printf(m, "SQEs:\t%u\n", sq_tail - ctx->cached_sq_head);
- sq_entries = min(sq_tail - sq_head, ctx->sq_entries);
- for (i = 0; i < sq_entries; i++) {
- unsigned int entry = i + sq_head;
- unsigned int sq_idx = READ_ONCE(ctx->sq_array[entry & sq_mask]);
- struct io_uring_sqe *sqe;
-
- if (sq_idx > sq_mask)
- continue;
- sqe = &ctx->sq_sqes[sq_idx];
- seq_printf(m, "%5u: opcode:%d, fd:%d, flags:%x, user_data:%llu\n",
- sq_idx, sqe->opcode, sqe->fd, sqe->flags,
- sqe->user_data);
- }
- seq_printf(m, "CQEs:\t%u\n", cq_tail - cq_head);
- cq_entries = min(cq_tail - cq_head, ctx->cq_entries);
- for (i = 0; i < cq_entries; i++) {
- unsigned int entry = i + cq_head;
- struct io_uring_cqe *cqe = &r->cqes[entry & cq_mask];
-
- seq_printf(m, "%5u: user_data:%llu, res:%d, flag:%x\n",
- entry & cq_mask, cqe->user_data, cqe->res,
- cqe->flags);
- }
-
- /*
- * Avoid ABBA deadlock between the seq lock and the io_uring mutex,
- * since fdinfo case grabs it in the opposite direction of normal use
- * cases. If we fail to get the lock, we just don't iterate any
- * structures that could be going away outside the io_uring mutex.
- */
- has_lock = mutex_trylock(&ctx->uring_lock);
-
- if (has_lock && (ctx->flags & IORING_SETUP_SQPOLL)) {
- sq = ctx->sq_data;
- if (!sq->thread)
- sq = NULL;
- }
-
- seq_printf(m, "SqThread:\t%d\n", sq ? task_pid_nr(sq->thread) : -1);
- seq_printf(m, "SqThreadCpu:\t%d\n", sq ? task_cpu(sq->thread) : -1);
- seq_printf(m, "UserFiles:\t%u\n", ctx->nr_user_files);
- for (i = 0; has_lock && i < ctx->nr_user_files; i++) {
- struct file *f = io_file_from_index(ctx, i);
-
- if (f)
- seq_printf(m, "%5u: %s\n", i, file_dentry(f)->d_iname);
- else
- seq_printf(m, "%5u: <none>\n", i);
- }
- seq_printf(m, "UserBufs:\t%u\n", ctx->nr_user_bufs);
- for (i = 0; has_lock && i < ctx->nr_user_bufs; i++) {
- struct io_mapped_ubuf *buf = ctx->user_bufs[i];
- unsigned int len = buf->ubuf_end - buf->ubuf;
-
- seq_printf(m, "%5u: 0x%llx/%u\n", i, buf->ubuf, len);
- }
- if (has_lock && !xa_empty(&ctx->personalities)) {
- unsigned long index;
- const struct cred *cred;
-
- seq_printf(m, "Personalities:\n");
- xa_for_each(&ctx->personalities, index, cred)
- io_uring_show_cred(m, index, cred);
- }
- if (has_lock)
- mutex_unlock(&ctx->uring_lock);
-
- seq_puts(m, "PollList:\n");
- spin_lock(&ctx->completion_lock);
- for (i = 0; i < (1U << ctx->cancel_hash_bits); i++) {
- struct hlist_head *list = &ctx->cancel_hash[i];
- struct io_kiocb *req;
-
- hlist_for_each_entry(req, list, hash_node)
- seq_printf(m, " op=%d, task_works=%d\n", req->opcode,
- req->task->task_works != NULL);
- }
-
- seq_puts(m, "CqOverflowList:\n");
- list_for_each_entry(ocqe, &ctx->cq_overflow_list, list) {
- struct io_uring_cqe *cqe = &ocqe->cqe;
-
- seq_printf(m, " user_data=%llu, res=%d, flags=%x\n",
- cqe->user_data, cqe->res, cqe->flags);
-
- }
-
- spin_unlock(&ctx->completion_lock);
-}
-
-static __cold void io_uring_show_fdinfo(struct seq_file *m, struct file *f)
-{
- struct io_ring_ctx *ctx = f->private_data;
-
- if (percpu_ref_tryget(&ctx->refs)) {
- __io_uring_show_fdinfo(ctx, m);
- percpu_ref_put(&ctx->refs);
- }
-}
-#endif
-
-static const struct file_operations io_uring_fops = {
- .release = io_uring_release,
- .mmap = io_uring_mmap,
-#ifndef CONFIG_MMU
- .get_unmapped_area = io_uring_nommu_get_unmapped_area,
- .mmap_capabilities = io_uring_nommu_mmap_capabilities,
-#endif
- .poll = io_uring_poll,
-#ifdef CONFIG_PROC_FS
- .show_fdinfo = io_uring_show_fdinfo,
-#endif
-};
-
-static __cold int io_allocate_scq_urings(struct io_ring_ctx *ctx,
- struct io_uring_params *p)
-{
- struct io_rings *rings;
- size_t size, sq_array_offset;
-
- /* make sure these are sane, as we already accounted them */
- ctx->sq_entries = p->sq_entries;
- ctx->cq_entries = p->cq_entries;
-
- size = rings_size(p->sq_entries, p->cq_entries, &sq_array_offset);
- if (size == SIZE_MAX)
- return -EOVERFLOW;
-
- rings = io_mem_alloc(size);
- if (!rings)
- return -ENOMEM;
-
- ctx->rings = rings;
- ctx->sq_array = (u32 *)((char *)rings + sq_array_offset);
- rings->sq_ring_mask = p->sq_entries - 1;
- rings->cq_ring_mask = p->cq_entries - 1;
- rings->sq_ring_entries = p->sq_entries;
- rings->cq_ring_entries = p->cq_entries;
-
- size = array_size(sizeof(struct io_uring_sqe), p->sq_entries);
- if (size == SIZE_MAX) {
- io_mem_free(ctx->rings);
- ctx->rings = NULL;
- return -EOVERFLOW;
- }
-
- ctx->sq_sqes = io_mem_alloc(size);
- if (!ctx->sq_sqes) {
- io_mem_free(ctx->rings);
- ctx->rings = NULL;
- return -ENOMEM;
- }
-
- return 0;
-}
-
-static int io_uring_install_fd(struct io_ring_ctx *ctx, struct file *file)
-{
- int ret, fd;
-
- fd = get_unused_fd_flags(O_RDWR | O_CLOEXEC);
- if (fd < 0)
- return fd;
-
- ret = io_uring_add_tctx_node(ctx);
- if (ret) {
- put_unused_fd(fd);
- return ret;
- }
- fd_install(fd, file);
- return fd;
-}
-
-/*
- * Allocate an anonymous fd, this is what constitutes the application
- * visible backing of an io_uring instance. The application mmaps this
- * fd to gain access to the SQ/CQ ring details. If UNIX sockets are enabled,
- * we have to tie this fd to a socket for file garbage collection purposes.
- */
-static struct file *io_uring_get_file(struct io_ring_ctx *ctx)
-{
- struct file *file;
-#if defined(CONFIG_UNIX)
- int ret;
-
- ret = sock_create_kern(&init_net, PF_UNIX, SOCK_RAW, IPPROTO_IP,
- &ctx->ring_sock);
- if (ret)
- return ERR_PTR(ret);
-#endif
-
- file = anon_inode_getfile_secure("[io_uring]", &io_uring_fops, ctx,
- O_RDWR | O_CLOEXEC, NULL);
-#if defined(CONFIG_UNIX)
- if (IS_ERR(file)) {
- sock_release(ctx->ring_sock);
- ctx->ring_sock = NULL;
- } else {
- ctx->ring_sock->file = file;
- }
-#endif
- return file;
-}
-
-static __cold int io_uring_create(unsigned entries, struct io_uring_params *p,
- struct io_uring_params __user *params)
-{
- struct io_ring_ctx *ctx;
- struct file *file;
- int ret;
-
- if (!entries)
- return -EINVAL;
- if (entries > IORING_MAX_ENTRIES) {
- if (!(p->flags & IORING_SETUP_CLAMP))
- return -EINVAL;
- entries = IORING_MAX_ENTRIES;
- }
-
- /*
- * Use twice as many entries for the CQ ring. It's possible for the
- * application to drive a higher depth than the size of the SQ ring,
- * since the sqes are only used at submission time. This allows for
- * some flexibility in overcommitting a bit. If the application has
- * set IORING_SETUP_CQSIZE, it will have passed in the desired number
- * of CQ ring entries manually.
- */
- p->sq_entries = roundup_pow_of_two(entries);
- if (p->flags & IORING_SETUP_CQSIZE) {
- /*
- * If IORING_SETUP_CQSIZE is set, we do the same roundup
- * to a power-of-two, if it isn't already. We do NOT impose
- * any cq vs sq ring sizing.
- */
- if (!p->cq_entries)
- return -EINVAL;
- if (p->cq_entries > IORING_MAX_CQ_ENTRIES) {
- if (!(p->flags & IORING_SETUP_CLAMP))
- return -EINVAL;
- p->cq_entries = IORING_MAX_CQ_ENTRIES;
- }
- p->cq_entries = roundup_pow_of_two(p->cq_entries);
- if (p->cq_entries < p->sq_entries)
- return -EINVAL;
- } else {
- p->cq_entries = 2 * p->sq_entries;
- }
-
- ctx = io_ring_ctx_alloc(p);
- if (!ctx)
- return -ENOMEM;
- ctx->compat = in_compat_syscall();
- if (!capable(CAP_IPC_LOCK))
- ctx->user = get_uid(current_user());
-
- /*
- * This is just grabbed for accounting purposes. When a process exits,
- * the mm is exited and dropped before the files, hence we need to hang
- * on to this mm purely for the purposes of being able to unaccount
- * memory (locked/pinned vm). It's not used for anything else.
- */
- mmgrab(current->mm);
- ctx->mm_account = current->mm;
-
- ret = io_allocate_scq_urings(ctx, p);
- if (ret)
- goto err;
-
- ret = io_sq_offload_create(ctx, p);
- if (ret)
- goto err;
- /* always set a rsrc node */
- ret = io_rsrc_node_switch_start(ctx);
- if (ret)
- goto err;
- io_rsrc_node_switch(ctx, NULL);
-
- memset(&p->sq_off, 0, sizeof(p->sq_off));
- p->sq_off.head = offsetof(struct io_rings, sq.head);
- p->sq_off.tail = offsetof(struct io_rings, sq.tail);
- p->sq_off.ring_mask = offsetof(struct io_rings, sq_ring_mask);
- p->sq_off.ring_entries = offsetof(struct io_rings, sq_ring_entries);
- p->sq_off.flags = offsetof(struct io_rings, sq_flags);
- p->sq_off.dropped = offsetof(struct io_rings, sq_dropped);
- p->sq_off.array = (char *)ctx->sq_array - (char *)ctx->rings;
-
- memset(&p->cq_off, 0, sizeof(p->cq_off));
- p->cq_off.head = offsetof(struct io_rings, cq.head);
- p->cq_off.tail = offsetof(struct io_rings, cq.tail);
- p->cq_off.ring_mask = offsetof(struct io_rings, cq_ring_mask);
- p->cq_off.ring_entries = offsetof(struct io_rings, cq_ring_entries);
- p->cq_off.overflow = offsetof(struct io_rings, cq_overflow);
- p->cq_off.cqes = offsetof(struct io_rings, cqes);
- p->cq_off.flags = offsetof(struct io_rings, cq_flags);
-
- p->features = IORING_FEAT_SINGLE_MMAP | IORING_FEAT_NODROP |
- IORING_FEAT_SUBMIT_STABLE | IORING_FEAT_RW_CUR_POS |
- IORING_FEAT_CUR_PERSONALITY | IORING_FEAT_FAST_POLL |
- IORING_FEAT_POLL_32BITS | IORING_FEAT_SQPOLL_NONFIXED |
- IORING_FEAT_EXT_ARG | IORING_FEAT_NATIVE_WORKERS |
- IORING_FEAT_RSRC_TAGS;
-
- if (copy_to_user(params, p, sizeof(*p))) {
- ret = -EFAULT;
- goto err;
- }
-
- file = io_uring_get_file(ctx);
- if (IS_ERR(file)) {
- ret = PTR_ERR(file);
- goto err;
- }
-
- /*
- * Install ring fd as the very last thing, so we don't risk someone
- * having closed it before we finish setup
- */
- ret = io_uring_install_fd(ctx, file);
- if (ret < 0) {
- /* fput will clean it up */
- fput(file);
- return ret;
- }
-
- trace_io_uring_create(ret, ctx, p->sq_entries, p->cq_entries, p->flags);
- return ret;
-err:
- io_ring_ctx_wait_and_kill(ctx);
- return ret;
-}
-
-/*
- * Sets up an aio uring context, and returns the fd. Applications asks for a
- * ring size, we return the actual sq/cq ring sizes (among other things) in the
- * params structure passed in.
- */
-static long io_uring_setup(u32 entries, struct io_uring_params __user *params)
-{
- struct io_uring_params p;
- int i;
-
- if (copy_from_user(&p, params, sizeof(p)))
- return -EFAULT;
- for (i = 0; i < ARRAY_SIZE(p.resv); i++) {
- if (p.resv[i])
- return -EINVAL;
- }
-
- if (p.flags & ~(IORING_SETUP_IOPOLL | IORING_SETUP_SQPOLL |
- IORING_SETUP_SQ_AFF | IORING_SETUP_CQSIZE |
- IORING_SETUP_CLAMP | IORING_SETUP_ATTACH_WQ |
- IORING_SETUP_R_DISABLED))
- return -EINVAL;
-
- return io_uring_create(entries, &p, params);
-}
-
-SYSCALL_DEFINE2(io_uring_setup, u32, entries,
- struct io_uring_params __user *, params)
-{
- return io_uring_setup(entries, params);
-}
-
-static __cold int io_probe(struct io_ring_ctx *ctx, void __user *arg,
- unsigned nr_args)
-{
- struct io_uring_probe *p;
- size_t size;
- int i, ret;
-
- size = struct_size(p, ops, nr_args);
- if (size == SIZE_MAX)
- return -EOVERFLOW;
- p = kzalloc(size, GFP_KERNEL);
- if (!p)
- return -ENOMEM;
-
- ret = -EFAULT;
- if (copy_from_user(p, arg, size))
- goto out;
- ret = -EINVAL;
- if (memchr_inv(p, 0, size))
- goto out;
-
- p->last_op = IORING_OP_LAST - 1;
- if (nr_args > IORING_OP_LAST)
- nr_args = IORING_OP_LAST;
-
- for (i = 0; i < nr_args; i++) {
- p->ops[i].op = i;
- if (!io_op_defs[i].not_supported)
- p->ops[i].flags = IO_URING_OP_SUPPORTED;
- }
- p->ops_len = i;
-
- ret = 0;
- if (copy_to_user(arg, p, size))
- ret = -EFAULT;
-out:
- kfree(p);
- return ret;
-}
-
-static int io_register_personality(struct io_ring_ctx *ctx)
-{
- const struct cred *creds;
- u32 id;
- int ret;
-
- creds = get_current_cred();
-
- ret = xa_alloc_cyclic(&ctx->personalities, &id, (void *)creds,
- XA_LIMIT(0, USHRT_MAX), &ctx->pers_next, GFP_KERNEL);
- if (ret < 0) {
- put_cred(creds);
- return ret;
- }
- return id;
-}
-
-static __cold int io_register_restrictions(struct io_ring_ctx *ctx,
- void __user *arg, unsigned int nr_args)
-{
- struct io_uring_restriction *res;
- size_t size;
- int i, ret;
-
- /* Restrictions allowed only if rings started disabled */
- if (!(ctx->flags & IORING_SETUP_R_DISABLED))
- return -EBADFD;
-
- /* We allow only a single restrictions registration */
- if (ctx->restrictions.registered)
- return -EBUSY;
-
- if (!arg || nr_args > IORING_MAX_RESTRICTIONS)
- return -EINVAL;
-
- size = array_size(nr_args, sizeof(*res));
- if (size == SIZE_MAX)
- return -EOVERFLOW;
-
- res = memdup_user(arg, size);
- if (IS_ERR(res))
- return PTR_ERR(res);
-
- ret = 0;
-
- for (i = 0; i < nr_args; i++) {
- switch (res[i].opcode) {
- case IORING_RESTRICTION_REGISTER_OP:
- if (res[i].register_op >= IORING_REGISTER_LAST) {
- ret = -EINVAL;
- goto out;
- }
-
- __set_bit(res[i].register_op,
- ctx->restrictions.register_op);
- break;
- case IORING_RESTRICTION_SQE_OP:
- if (res[i].sqe_op >= IORING_OP_LAST) {
- ret = -EINVAL;
- goto out;
- }
-
- __set_bit(res[i].sqe_op, ctx->restrictions.sqe_op);
- break;
- case IORING_RESTRICTION_SQE_FLAGS_ALLOWED:
- ctx->restrictions.sqe_flags_allowed = res[i].sqe_flags;
- break;
- case IORING_RESTRICTION_SQE_FLAGS_REQUIRED:
- ctx->restrictions.sqe_flags_required = res[i].sqe_flags;
- break;
- default:
- ret = -EINVAL;
- goto out;
- }
- }
-
-out:
- /* Reset all restrictions if an error happened */
- if (ret != 0)
- memset(&ctx->restrictions, 0, sizeof(ctx->restrictions));
- else
- ctx->restrictions.registered = true;
-
- kfree(res);
- return ret;
-}
-
-static int io_register_enable_rings(struct io_ring_ctx *ctx)
-{
- if (!(ctx->flags & IORING_SETUP_R_DISABLED))
- return -EBADFD;
-
- if (ctx->restrictions.registered)
- ctx->restricted = 1;
-
- ctx->flags &= ~IORING_SETUP_R_DISABLED;
- if (ctx->sq_data && wq_has_sleeper(&ctx->sq_data->wait))
- wake_up(&ctx->sq_data->wait);
- return 0;
-}
-
-static int __io_register_rsrc_update(struct io_ring_ctx *ctx, unsigned type,
- struct io_uring_rsrc_update2 *up,
- unsigned nr_args)
-{
- __u32 tmp;
- int err;
-
- if (up->resv)
- return -EINVAL;
- if (check_add_overflow(up->offset, nr_args, &tmp))
- return -EOVERFLOW;
- err = io_rsrc_node_switch_start(ctx);
- if (err)
- return err;
-
- switch (type) {
- case IORING_RSRC_FILE:
- return __io_sqe_files_update(ctx, up, nr_args);
- case IORING_RSRC_BUFFER:
- return __io_sqe_buffers_update(ctx, up, nr_args);
- }
- return -EINVAL;
-}
-
-static int io_register_files_update(struct io_ring_ctx *ctx, void __user *arg,
- unsigned nr_args)
-{
- struct io_uring_rsrc_update2 up;
-
- if (!nr_args)
- return -EINVAL;
- memset(&up, 0, sizeof(up));
- if (copy_from_user(&up, arg, sizeof(struct io_uring_rsrc_update)))
- return -EFAULT;
- return __io_register_rsrc_update(ctx, IORING_RSRC_FILE, &up, nr_args);
-}
-
-static int io_register_rsrc_update(struct io_ring_ctx *ctx, void __user *arg,
- unsigned size, unsigned type)
-{
- struct io_uring_rsrc_update2 up;
-
- if (size != sizeof(up))
- return -EINVAL;
- if (copy_from_user(&up, arg, sizeof(up)))
- return -EFAULT;
- if (!up.nr || up.resv)
- return -EINVAL;
- return __io_register_rsrc_update(ctx, type, &up, up.nr);
-}
-
-static __cold int io_register_rsrc(struct io_ring_ctx *ctx, void __user *arg,
- unsigned int size, unsigned int type)
-{
- struct io_uring_rsrc_register rr;
-
- /* keep it extendible */
- if (size != sizeof(rr))
- return -EINVAL;
-
- memset(&rr, 0, sizeof(rr));
- if (copy_from_user(&rr, arg, size))
- return -EFAULT;
- if (!rr.nr || rr.resv || rr.resv2)
- return -EINVAL;
-
- switch (type) {
- case IORING_RSRC_FILE:
- return io_sqe_files_register(ctx, u64_to_user_ptr(rr.data),
- rr.nr, u64_to_user_ptr(rr.tags));
- case IORING_RSRC_BUFFER:
- return io_sqe_buffers_register(ctx, u64_to_user_ptr(rr.data),
- rr.nr, u64_to_user_ptr(rr.tags));
- }
- return -EINVAL;
-}
-
-static __cold int io_register_iowq_aff(struct io_ring_ctx *ctx,
- void __user *arg, unsigned len)
-{
- struct io_uring_task *tctx = current->io_uring;
- cpumask_var_t new_mask;
- int ret;
-
- if (!tctx || !tctx->io_wq)
- return -EINVAL;
-
- if (!alloc_cpumask_var(&new_mask, GFP_KERNEL))
- return -ENOMEM;
-
- cpumask_clear(new_mask);
- if (len > cpumask_size())
- len = cpumask_size();
-
- if (copy_from_user(new_mask, arg, len)) {
- free_cpumask_var(new_mask);
- return -EFAULT;
- }
-
- ret = io_wq_cpu_affinity(tctx->io_wq, new_mask);
- free_cpumask_var(new_mask);
- return ret;
-}
-
-static __cold int io_unregister_iowq_aff(struct io_ring_ctx *ctx)
-{
- struct io_uring_task *tctx = current->io_uring;
-
- if (!tctx || !tctx->io_wq)
- return -EINVAL;
-
- return io_wq_cpu_affinity(tctx->io_wq, NULL);
-}
-
-static __cold int io_register_iowq_max_workers(struct io_ring_ctx *ctx,
- void __user *arg)
- __must_hold(&ctx->uring_lock)
-{
- struct io_tctx_node *node;
- struct io_uring_task *tctx = NULL;
- struct io_sq_data *sqd = NULL;
- __u32 new_count[2];
- int i, ret;
-
- if (copy_from_user(new_count, arg, sizeof(new_count)))
- return -EFAULT;
- for (i = 0; i < ARRAY_SIZE(new_count); i++)
- if (new_count[i] > INT_MAX)
- return -EINVAL;
-
- if (ctx->flags & IORING_SETUP_SQPOLL) {
- sqd = ctx->sq_data;
- if (sqd) {
- /*
- * Observe the correct sqd->lock -> ctx->uring_lock
- * ordering. Fine to drop uring_lock here, we hold
- * a ref to the ctx.
- */
- refcount_inc(&sqd->refs);
- mutex_unlock(&ctx->uring_lock);
- mutex_lock(&sqd->lock);
- mutex_lock(&ctx->uring_lock);
- if (sqd->thread)
- tctx = sqd->thread->io_uring;
- }
- } else {
- tctx = current->io_uring;
- }
-
- BUILD_BUG_ON(sizeof(new_count) != sizeof(ctx->iowq_limits));
-
- for (i = 0; i < ARRAY_SIZE(new_count); i++)
- if (new_count[i])
- ctx->iowq_limits[i] = new_count[i];
- ctx->iowq_limits_set = true;
-
- if (tctx && tctx->io_wq) {
- ret = io_wq_max_workers(tctx->io_wq, new_count);
- if (ret)
- goto err;
- } else {
- memset(new_count, 0, sizeof(new_count));
- }
-
- if (sqd) {
- mutex_unlock(&sqd->lock);
- io_put_sq_data(sqd);
- }
-
- if (copy_to_user(arg, new_count, sizeof(new_count)))
- return -EFAULT;
-
- /* that's it for SQPOLL, only the SQPOLL task creates requests */
- if (sqd)
- return 0;
-
- /* now propagate the restriction to all registered users */
- list_for_each_entry(node, &ctx->tctx_list, ctx_node) {
- struct io_uring_task *tctx = node->task->io_uring;
-
- if (WARN_ON_ONCE(!tctx->io_wq))
- continue;
-
- for (i = 0; i < ARRAY_SIZE(new_count); i++)
- new_count[i] = ctx->iowq_limits[i];
- /* ignore errors, it always returns zero anyway */
- (void)io_wq_max_workers(tctx->io_wq, new_count);
- }
- return 0;
-err:
- if (sqd) {
- mutex_unlock(&sqd->lock);
- io_put_sq_data(sqd);
- }
- return ret;
-}
-
-static bool io_register_op_must_quiesce(int op)
-{
- switch (op) {
- case IORING_REGISTER_BUFFERS:
- case IORING_UNREGISTER_BUFFERS:
- case IORING_REGISTER_FILES:
- case IORING_UNREGISTER_FILES:
- case IORING_REGISTER_FILES_UPDATE:
- case IORING_REGISTER_PROBE:
- case IORING_REGISTER_PERSONALITY:
- case IORING_UNREGISTER_PERSONALITY:
- case IORING_REGISTER_FILES2:
- case IORING_REGISTER_FILES_UPDATE2:
- case IORING_REGISTER_BUFFERS2:
- case IORING_REGISTER_BUFFERS_UPDATE:
- case IORING_REGISTER_IOWQ_AFF:
- case IORING_UNREGISTER_IOWQ_AFF:
- case IORING_REGISTER_IOWQ_MAX_WORKERS:
- return false;
- default:
- return true;
- }
-}
-
-static __cold int io_ctx_quiesce(struct io_ring_ctx *ctx)
-{
- long ret;
-
- percpu_ref_kill(&ctx->refs);
-
- /*
- * Drop uring mutex before waiting for references to exit. If another
- * thread is currently inside io_uring_enter() it might need to grab the
- * uring_lock to make progress. If we hold it here across the drain
- * wait, then we can deadlock. It's safe to drop the mutex here, since
- * no new references will come in after we've killed the percpu ref.
- */
- mutex_unlock(&ctx->uring_lock);
- do {
- ret = wait_for_completion_interruptible_timeout(&ctx->ref_comp, HZ);
- if (ret) {
- ret = min(0L, ret);
- break;
- }
-
- ret = io_run_task_work_sig();
- io_req_caches_free(ctx);
- } while (ret >= 0);
- mutex_lock(&ctx->uring_lock);
-
- if (ret)
- io_refs_resurrect(&ctx->refs, &ctx->ref_comp);
- return ret;
-}
-
-static int __io_uring_register(struct io_ring_ctx *ctx, unsigned opcode,
- void __user *arg, unsigned nr_args)
- __releases(ctx->uring_lock)
- __acquires(ctx->uring_lock)
-{
- int ret;
-
- /*
- * We're inside the ring mutex, if the ref is already dying, then
- * someone else killed the ctx or is already going through
- * io_uring_register().
- */
- if (percpu_ref_is_dying(&ctx->refs))
- return -ENXIO;
-
- if (ctx->restricted) {
- if (opcode >= IORING_REGISTER_LAST)
- return -EINVAL;
- opcode = array_index_nospec(opcode, IORING_REGISTER_LAST);
- if (!test_bit(opcode, ctx->restrictions.register_op))
- return -EACCES;
- }
-
- if (io_register_op_must_quiesce(opcode)) {
- ret = io_ctx_quiesce(ctx);
- if (ret)
- return ret;
- }
-
- switch (opcode) {
- case IORING_REGISTER_BUFFERS:
- ret = io_sqe_buffers_register(ctx, arg, nr_args, NULL);
- break;
- case IORING_UNREGISTER_BUFFERS:
- ret = -EINVAL;
- if (arg || nr_args)
- break;
- ret = io_sqe_buffers_unregister(ctx);
- break;
- case IORING_REGISTER_FILES:
- ret = io_sqe_files_register(ctx, arg, nr_args, NULL);
- break;
- case IORING_UNREGISTER_FILES:
- ret = -EINVAL;
- if (arg || nr_args)
- break;
- ret = io_sqe_files_unregister(ctx);
- break;
- case IORING_REGISTER_FILES_UPDATE:
- ret = io_register_files_update(ctx, arg, nr_args);
- break;
- case IORING_REGISTER_EVENTFD:
- case IORING_REGISTER_EVENTFD_ASYNC:
- ret = -EINVAL;
- if (nr_args != 1)
- break;
- ret = io_eventfd_register(ctx, arg);
- if (ret)
- break;
- if (opcode == IORING_REGISTER_EVENTFD_ASYNC)
- ctx->eventfd_async = 1;
- else
- ctx->eventfd_async = 0;
- break;
- case IORING_UNREGISTER_EVENTFD:
- ret = -EINVAL;
- if (arg || nr_args)
- break;
- ret = io_eventfd_unregister(ctx);
- break;
- case IORING_REGISTER_PROBE:
- ret = -EINVAL;
- if (!arg || nr_args > 256)
- break;
- ret = io_probe(ctx, arg, nr_args);
- break;
- case IORING_REGISTER_PERSONALITY:
- ret = -EINVAL;
- if (arg || nr_args)
- break;
- ret = io_register_personality(ctx);
- break;
- case IORING_UNREGISTER_PERSONALITY:
- ret = -EINVAL;
- if (arg)
- break;
- ret = io_unregister_personality(ctx, nr_args);
- break;
- case IORING_REGISTER_ENABLE_RINGS:
- ret = -EINVAL;
- if (arg || nr_args)
- break;
- ret = io_register_enable_rings(ctx);
- break;
- case IORING_REGISTER_RESTRICTIONS:
- ret = io_register_restrictions(ctx, arg, nr_args);
- break;
- case IORING_REGISTER_FILES2:
- ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_FILE);
- break;
- case IORING_REGISTER_FILES_UPDATE2:
- ret = io_register_rsrc_update(ctx, arg, nr_args,
- IORING_RSRC_FILE);
- break;
- case IORING_REGISTER_BUFFERS2:
- ret = io_register_rsrc(ctx, arg, nr_args, IORING_RSRC_BUFFER);
- break;
- case IORING_REGISTER_BUFFERS_UPDATE:
- ret = io_register_rsrc_update(ctx, arg, nr_args,
- IORING_RSRC_BUFFER);
- break;
- case IORING_REGISTER_IOWQ_AFF:
- ret = -EINVAL;
- if (!arg || !nr_args)
- break;
- ret = io_register_iowq_aff(ctx, arg, nr_args);
- break;
- case IORING_UNREGISTER_IOWQ_AFF:
- ret = -EINVAL;
- if (arg || nr_args)
- break;
- ret = io_unregister_iowq_aff(ctx);
- break;
- case IORING_REGISTER_IOWQ_MAX_WORKERS:
- ret = -EINVAL;
- if (!arg || nr_args != 2)
- break;
- ret = io_register_iowq_max_workers(ctx, arg);
- break;
- default:
- ret = -EINVAL;
- break;
- }
-
- if (io_register_op_must_quiesce(opcode)) {
- /* bring the ctx back to life */
- percpu_ref_reinit(&ctx->refs);
- reinit_completion(&ctx->ref_comp);
- }
- return ret;
-}
-
-SYSCALL_DEFINE4(io_uring_register, unsigned int, fd, unsigned int, opcode,
- void __user *, arg, unsigned int, nr_args)
-{
- struct io_ring_ctx *ctx;
- long ret = -EBADF;
- struct fd f;
-
- f = fdget(fd);
- if (!f.file)
- return -EBADF;
-
- ret = -EOPNOTSUPP;
- if (f.file->f_op != &io_uring_fops)
- goto out_fput;
-
- ctx = f.file->private_data;
-
- io_run_task_work();
-
- mutex_lock(&ctx->uring_lock);
- ret = __io_uring_register(ctx, opcode, arg, nr_args);
- mutex_unlock(&ctx->uring_lock);
- trace_io_uring_register(ctx, opcode, ctx->nr_user_files, ctx->nr_user_bufs,
- ctx->cq_ev_fd != NULL, ret);
-out_fput:
- fdput(f);
- return ret;
-}
-
-static int __init io_uring_init(void)
-{
-#define __BUILD_BUG_VERIFY_ELEMENT(stype, eoffset, etype, ename) do { \
- BUILD_BUG_ON(offsetof(stype, ename) != eoffset); \
- BUILD_BUG_ON(sizeof(etype) != sizeof_field(stype, ename)); \
-} while (0)
-
-#define BUILD_BUG_SQE_ELEM(eoffset, etype, ename) \
- __BUILD_BUG_VERIFY_ELEMENT(struct io_uring_sqe, eoffset, etype, ename)
- BUILD_BUG_ON(sizeof(struct io_uring_sqe) != 64);
- BUILD_BUG_SQE_ELEM(0, __u8, opcode);
- BUILD_BUG_SQE_ELEM(1, __u8, flags);
- BUILD_BUG_SQE_ELEM(2, __u16, ioprio);
- BUILD_BUG_SQE_ELEM(4, __s32, fd);
- BUILD_BUG_SQE_ELEM(8, __u64, off);
- BUILD_BUG_SQE_ELEM(8, __u64, addr2);
- BUILD_BUG_SQE_ELEM(16, __u64, addr);
- BUILD_BUG_SQE_ELEM(16, __u64, splice_off_in);
- BUILD_BUG_SQE_ELEM(24, __u32, len);
- BUILD_BUG_SQE_ELEM(28, __kernel_rwf_t, rw_flags);
- BUILD_BUG_SQE_ELEM(28, /* compat */ int, rw_flags);
- BUILD_BUG_SQE_ELEM(28, /* compat */ __u32, rw_flags);
- BUILD_BUG_SQE_ELEM(28, __u32, fsync_flags);
- BUILD_BUG_SQE_ELEM(28, /* compat */ __u16, poll_events);
- BUILD_BUG_SQE_ELEM(28, __u32, poll32_events);
- BUILD_BUG_SQE_ELEM(28, __u32, sync_range_flags);
- BUILD_BUG_SQE_ELEM(28, __u32, msg_flags);
- BUILD_BUG_SQE_ELEM(28, __u32, timeout_flags);
- BUILD_BUG_SQE_ELEM(28, __u32, accept_flags);
- BUILD_BUG_SQE_ELEM(28, __u32, cancel_flags);
- BUILD_BUG_SQE_ELEM(28, __u32, open_flags);
- BUILD_BUG_SQE_ELEM(28, __u32, statx_flags);
- BUILD_BUG_SQE_ELEM(28, __u32, fadvise_advice);
- BUILD_BUG_SQE_ELEM(28, __u32, splice_flags);
- BUILD_BUG_SQE_ELEM(32, __u64, user_data);
- BUILD_BUG_SQE_ELEM(40, __u16, buf_index);
- BUILD_BUG_SQE_ELEM(40, __u16, buf_group);
- BUILD_BUG_SQE_ELEM(42, __u16, personality);
- BUILD_BUG_SQE_ELEM(44, __s32, splice_fd_in);
- BUILD_BUG_SQE_ELEM(44, __u32, file_index);
-
- BUILD_BUG_ON(sizeof(struct io_uring_files_update) !=
- sizeof(struct io_uring_rsrc_update));
- BUILD_BUG_ON(sizeof(struct io_uring_rsrc_update) >
- sizeof(struct io_uring_rsrc_update2));
-
- /* ->buf_index is u16 */
- BUILD_BUG_ON(IORING_MAX_REG_BUFFERS >= (1u << 16));
-
- /* should fit into one byte */
- BUILD_BUG_ON(SQE_VALID_FLAGS >= (1 << 8));
- BUILD_BUG_ON(SQE_COMMON_FLAGS >= (1 << 8));
- BUILD_BUG_ON((SQE_VALID_FLAGS | SQE_COMMON_FLAGS) != SQE_VALID_FLAGS);
-
- BUILD_BUG_ON(ARRAY_SIZE(io_op_defs) != IORING_OP_LAST);
- BUILD_BUG_ON(__REQ_F_LAST_BIT > 8 * sizeof(int));
-
- req_cachep = KMEM_CACHE(io_kiocb, SLAB_HWCACHE_ALIGN | SLAB_PANIC |
- SLAB_ACCOUNT);
- return 0;
-};
-__initcall(io_uring_init);
Copyright © 1996 – 2023 Jason A. Donenfeld. All Rights Reverse Engineered.