diff options
Diffstat (limited to 'fs/ksmbd/vfs_cache.c')
| -rw-r--r-- | fs/ksmbd/vfs_cache.c | 709 |
1 files changed, 709 insertions, 0 deletions
diff --git a/fs/ksmbd/vfs_cache.c b/fs/ksmbd/vfs_cache.c new file mode 100644 index 000000000000..da9163b00350 --- /dev/null +++ b/fs/ksmbd/vfs_cache.c @@ -0,0 +1,709 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2016 Namjae Jeon <linkinjeon@kernel.org> + * Copyright (C) 2019 Samsung Electronics Co., Ltd. + */ + +#include <linux/fs.h> +#include <linux/slab.h> +#include <linux/vmalloc.h> + +#include "glob.h" +#include "vfs_cache.h" +#include "oplock.h" +#include "vfs.h" +#include "connection.h" +#include "mgmt/tree_connect.h" +#include "mgmt/user_session.h" +#include "smb_common.h" + +#define S_DEL_PENDING 1 +#define S_DEL_ON_CLS 2 +#define S_DEL_ON_CLS_STREAM 8 + +static unsigned int inode_hash_mask __read_mostly; +static unsigned int inode_hash_shift __read_mostly; +static struct hlist_head *inode_hashtable __read_mostly; +static DEFINE_RWLOCK(inode_hash_lock); + +static struct ksmbd_file_table global_ft; +static atomic_long_t fd_limit; +static struct kmem_cache *filp_cache; + +void ksmbd_set_fd_limit(unsigned long limit) +{ + limit = min(limit, get_max_files()); + atomic_long_set(&fd_limit, limit); +} + +static bool fd_limit_depleted(void) +{ + long v = atomic_long_dec_return(&fd_limit); + + if (v >= 0) + return false; + atomic_long_inc(&fd_limit); + return true; +} + +static void fd_limit_close(void) +{ + atomic_long_inc(&fd_limit); +} + +/* + * INODE hash + */ + +static unsigned long inode_hash(struct super_block *sb, unsigned long hashval) +{ + unsigned long tmp; + + tmp = (hashval * (unsigned long)sb) ^ (GOLDEN_RATIO_PRIME + hashval) / + L1_CACHE_BYTES; + tmp = tmp ^ ((tmp ^ GOLDEN_RATIO_PRIME) >> inode_hash_shift); + return tmp & inode_hash_mask; +} + +static struct ksmbd_inode *__ksmbd_inode_lookup(struct inode *inode) +{ + struct hlist_head *head = inode_hashtable + + inode_hash(inode->i_sb, inode->i_ino); + struct ksmbd_inode *ci = NULL, *ret_ci = NULL; + + hlist_for_each_entry(ci, head, m_hash) { + if (ci->m_inode == inode) { + if (atomic_inc_not_zero(&ci->m_count)) + ret_ci = ci; + break; + } + } + return ret_ci; +} + +static struct ksmbd_inode *ksmbd_inode_lookup(struct ksmbd_file *fp) +{ + return __ksmbd_inode_lookup(file_inode(fp->filp)); +} + +static struct ksmbd_inode *ksmbd_inode_lookup_by_vfsinode(struct inode *inode) +{ + struct ksmbd_inode *ci; + + read_lock(&inode_hash_lock); + ci = __ksmbd_inode_lookup(inode); + read_unlock(&inode_hash_lock); + return ci; +} + +int ksmbd_query_inode_status(struct inode *inode) +{ + struct ksmbd_inode *ci; + int ret = KSMBD_INODE_STATUS_UNKNOWN; + + read_lock(&inode_hash_lock); + ci = __ksmbd_inode_lookup(inode); + if (ci) { + ret = KSMBD_INODE_STATUS_OK; + if (ci->m_flags & S_DEL_PENDING) + ret = KSMBD_INODE_STATUS_PENDING_DELETE; + atomic_dec(&ci->m_count); + } + read_unlock(&inode_hash_lock); + return ret; +} + +bool ksmbd_inode_pending_delete(struct ksmbd_file *fp) +{ + return (fp->f_ci->m_flags & S_DEL_PENDING); +} + +void ksmbd_set_inode_pending_delete(struct ksmbd_file *fp) +{ + fp->f_ci->m_flags |= S_DEL_PENDING; +} + +void ksmbd_clear_inode_pending_delete(struct ksmbd_file *fp) +{ + fp->f_ci->m_flags &= ~S_DEL_PENDING; +} + +void ksmbd_fd_set_delete_on_close(struct ksmbd_file *fp, + int file_info) +{ + if (ksmbd_stream_fd(fp)) { + fp->f_ci->m_flags |= S_DEL_ON_CLS_STREAM; + return; + } + + fp->f_ci->m_flags |= S_DEL_ON_CLS; +} + +static void ksmbd_inode_hash(struct ksmbd_inode *ci) +{ + struct hlist_head *b = inode_hashtable + + inode_hash(ci->m_inode->i_sb, ci->m_inode->i_ino); + + hlist_add_head(&ci->m_hash, b); +} + +static void ksmbd_inode_unhash(struct ksmbd_inode *ci) +{ + write_lock(&inode_hash_lock); + hlist_del_init(&ci->m_hash); + write_unlock(&inode_hash_lock); +} + +static int ksmbd_inode_init(struct ksmbd_inode *ci, struct ksmbd_file *fp) +{ + ci->m_inode = file_inode(fp->filp); + atomic_set(&ci->m_count, 1); + atomic_set(&ci->op_count, 0); + atomic_set(&ci->sop_count, 0); + ci->m_flags = 0; + ci->m_fattr = 0; + INIT_LIST_HEAD(&ci->m_fp_list); + INIT_LIST_HEAD(&ci->m_op_list); + rwlock_init(&ci->m_lock); + return 0; +} + +static struct ksmbd_inode *ksmbd_inode_get(struct ksmbd_file *fp) +{ + struct ksmbd_inode *ci, *tmpci; + int rc; + + read_lock(&inode_hash_lock); + ci = ksmbd_inode_lookup(fp); + read_unlock(&inode_hash_lock); + if (ci) + return ci; + + ci = kmalloc(sizeof(struct ksmbd_inode), GFP_KERNEL); + if (!ci) + return NULL; + + rc = ksmbd_inode_init(ci, fp); + if (rc) { + pr_err("inode initialized failed\n"); + kfree(ci); + return NULL; + } + + write_lock(&inode_hash_lock); + tmpci = ksmbd_inode_lookup(fp); + if (!tmpci) { + ksmbd_inode_hash(ci); + } else { + kfree(ci); + ci = tmpci; + } + write_unlock(&inode_hash_lock); + return ci; +} + +static void ksmbd_inode_free(struct ksmbd_inode *ci) +{ + ksmbd_inode_unhash(ci); + kfree(ci); +} + +static void ksmbd_inode_put(struct ksmbd_inode *ci) +{ + if (atomic_dec_and_test(&ci->m_count)) + ksmbd_inode_free(ci); +} + +int __init ksmbd_inode_hash_init(void) +{ + unsigned int loop; + unsigned long numentries = 16384; + unsigned long bucketsize = sizeof(struct hlist_head); + unsigned long size; + + inode_hash_shift = ilog2(numentries); + inode_hash_mask = (1 << inode_hash_shift) - 1; + + size = bucketsize << inode_hash_shift; + + /* init master fp hash table */ + inode_hashtable = vmalloc(size); + if (!inode_hashtable) + return -ENOMEM; + + for (loop = 0; loop < (1U << inode_hash_shift); loop++) + INIT_HLIST_HEAD(&inode_hashtable[loop]); + return 0; +} + +void ksmbd_release_inode_hash(void) +{ + vfree(inode_hashtable); +} + +static void __ksmbd_inode_close(struct ksmbd_file *fp) +{ + struct dentry *dir, *dentry; + struct ksmbd_inode *ci = fp->f_ci; + int err; + struct file *filp; + + filp = fp->filp; + if (ksmbd_stream_fd(fp) && (ci->m_flags & S_DEL_ON_CLS_STREAM)) { + ci->m_flags &= ~S_DEL_ON_CLS_STREAM; + err = ksmbd_vfs_remove_xattr(file_mnt_user_ns(filp), + filp->f_path.dentry, + fp->stream.name); + if (err) + pr_err("remove xattr failed : %s\n", + fp->stream.name); + } + + if (atomic_dec_and_test(&ci->m_count)) { + write_lock(&ci->m_lock); + if (ci->m_flags & (S_DEL_ON_CLS | S_DEL_PENDING)) { + dentry = filp->f_path.dentry; + dir = dentry->d_parent; + ci->m_flags &= ~(S_DEL_ON_CLS | S_DEL_PENDING); + write_unlock(&ci->m_lock); + ksmbd_vfs_unlink(file_mnt_user_ns(filp), dir, dentry); + write_lock(&ci->m_lock); + } + write_unlock(&ci->m_lock); + + ksmbd_inode_free(ci); + } +} + +static void __ksmbd_remove_durable_fd(struct ksmbd_file *fp) +{ + if (!has_file_id(fp->persistent_id)) + return; + + write_lock(&global_ft.lock); + idr_remove(global_ft.idr, fp->persistent_id); + write_unlock(&global_ft.lock); +} + +static void __ksmbd_remove_fd(struct ksmbd_file_table *ft, struct ksmbd_file *fp) +{ + if (!has_file_id(fp->volatile_id)) + return; + + write_lock(&fp->f_ci->m_lock); + list_del_init(&fp->node); + write_unlock(&fp->f_ci->m_lock); + + write_lock(&ft->lock); + idr_remove(ft->idr, fp->volatile_id); + write_unlock(&ft->lock); +} + +static void __ksmbd_close_fd(struct ksmbd_file_table *ft, struct ksmbd_file *fp) +{ + struct file *filp; + struct ksmbd_lock *smb_lock, *tmp_lock; + + fd_limit_close(); + __ksmbd_remove_durable_fd(fp); + __ksmbd_remove_fd(ft, fp); + + close_id_del_oplock(fp); + filp = fp->filp; + + __ksmbd_inode_close(fp); + if (!IS_ERR_OR_NULL(filp)) + fput(filp); + + /* because the reference count of fp is 0, it is guaranteed that + * there are not accesses to fp->lock_list. + */ + list_for_each_entry_safe(smb_lock, tmp_lock, &fp->lock_list, flist) { + spin_lock(&fp->conn->llist_lock); + list_del(&smb_lock->clist); + spin_unlock(&fp->conn->llist_lock); + + list_del(&smb_lock->flist); + locks_free_lock(smb_lock->fl); + kfree(smb_lock); + } + + if (ksmbd_stream_fd(fp)) + kfree(fp->stream.name); + kmem_cache_free(filp_cache, fp); +} + +static struct ksmbd_file *ksmbd_fp_get(struct ksmbd_file *fp) +{ + if (!atomic_inc_not_zero(&fp->refcount)) + return NULL; + return fp; +} + +static struct ksmbd_file *__ksmbd_lookup_fd(struct ksmbd_file_table *ft, + u64 id) +{ + struct ksmbd_file *fp; + + if (!has_file_id(id)) + return NULL; + + read_lock(&ft->lock); + fp = idr_find(ft->idr, id); + if (fp) + fp = ksmbd_fp_get(fp); + read_unlock(&ft->lock); + return fp; +} + +static void __put_fd_final(struct ksmbd_work *work, struct ksmbd_file *fp) +{ + __ksmbd_close_fd(&work->sess->file_table, fp); + atomic_dec(&work->conn->stats.open_files_count); +} + +static void set_close_state_blocked_works(struct ksmbd_file *fp) +{ + struct ksmbd_work *cancel_work, *ctmp; + + spin_lock(&fp->f_lock); + list_for_each_entry_safe(cancel_work, ctmp, &fp->blocked_works, + fp_entry) { + list_del(&cancel_work->fp_entry); + cancel_work->state = KSMBD_WORK_CLOSED; + cancel_work->cancel_fn(cancel_work->cancel_argv); + } + spin_unlock(&fp->f_lock); +} + +int ksmbd_close_fd(struct ksmbd_work *work, u64 id) +{ + struct ksmbd_file *fp; + struct ksmbd_file_table *ft; + + if (!has_file_id(id)) + return 0; + + ft = &work->sess->file_table; + read_lock(&ft->lock); + fp = idr_find(ft->idr, id); + if (fp) { + set_close_state_blocked_works(fp); + + if (!atomic_dec_and_test(&fp->refcount)) + fp = NULL; + } + read_unlock(&ft->lock); + + if (!fp) + return -EINVAL; + + __put_fd_final(work, fp); + return 0; +} + +void ksmbd_fd_put(struct ksmbd_work *work, struct ksmbd_file *fp) +{ + if (!fp) + return; + + if (!atomic_dec_and_test(&fp->refcount)) + return; + __put_fd_final(work, fp); +} + +static bool __sanity_check(struct ksmbd_tree_connect *tcon, struct ksmbd_file *fp) +{ + if (!fp) + return false; + if (fp->tcon != tcon) + return false; + return true; +} + +struct ksmbd_file *ksmbd_lookup_foreign_fd(struct ksmbd_work *work, u64 id) +{ + return __ksmbd_lookup_fd(&work->sess->file_table, id); +} + +struct ksmbd_file *ksmbd_lookup_fd_fast(struct ksmbd_work *work, u64 id) +{ + struct ksmbd_file *fp = __ksmbd_lookup_fd(&work->sess->file_table, id); + + if (__sanity_check(work->tcon, fp)) + return fp; + + ksmbd_fd_put(work, fp); + return NULL; +} + +struct ksmbd_file *ksmbd_lookup_fd_slow(struct ksmbd_work *work, u64 id, + u64 pid) +{ + struct ksmbd_file *fp; + + if (!has_file_id(id)) { + id = work->compound_fid; + pid = work->compound_pfid; + } + + fp = __ksmbd_lookup_fd(&work->sess->file_table, id); + if (!__sanity_check(work->tcon, fp)) { + ksmbd_fd_put(work, fp); + return NULL; + } + if (fp->persistent_id != pid) { + ksmbd_fd_put(work, fp); + return NULL; + } + return fp; +} + +struct ksmbd_file *ksmbd_lookup_durable_fd(unsigned long long id) +{ + return __ksmbd_lookup_fd(&global_ft, id); +} + +struct ksmbd_file *ksmbd_lookup_fd_cguid(char *cguid) +{ + struct ksmbd_file *fp = NULL; + unsigned int id; + + read_lock(&global_ft.lock); + idr_for_each_entry(global_ft.idr, fp, id) { + if (!memcmp(fp->create_guid, + cguid, + SMB2_CREATE_GUID_SIZE)) { + fp = ksmbd_fp_get(fp); + break; + } + } + read_unlock(&global_ft.lock); + + return fp; +} + +struct ksmbd_file *ksmbd_lookup_fd_inode(struct inode *inode) +{ + struct ksmbd_file *lfp; + struct ksmbd_inode *ci; + + ci = ksmbd_inode_lookup_by_vfsinode(inode); + if (!ci) + return NULL; + + read_lock(&ci->m_lock); + list_for_each_entry(lfp, &ci->m_fp_list, node) { + if (inode == file_inode(lfp->filp)) { + atomic_dec(&ci->m_count); + lfp = ksmbd_fp_get(lfp); + read_unlock(&ci->m_lock); + return lfp; + } + } + atomic_dec(&ci->m_count); + read_unlock(&ci->m_lock); + return NULL; +} + +#define OPEN_ID_TYPE_VOLATILE_ID (0) +#define OPEN_ID_TYPE_PERSISTENT_ID (1) + +static void __open_id_set(struct ksmbd_file *fp, u64 id, int type) +{ + if (type == OPEN_ID_TYPE_VOLATILE_ID) + fp->volatile_id = id; + if (type == OPEN_ID_TYPE_PERSISTENT_ID) + fp->persistent_id = id; +} + +static int __open_id(struct ksmbd_file_table *ft, struct ksmbd_file *fp, + int type) +{ + u64 id = 0; + int ret; + + if (type == OPEN_ID_TYPE_VOLATILE_ID && fd_limit_depleted()) { + __open_id_set(fp, KSMBD_NO_FID, type); + return -EMFILE; + } + + idr_preload(GFP_KERNEL); + write_lock(&ft->lock); + ret = idr_alloc_cyclic(ft->idr, fp, 0, INT_MAX - 1, GFP_NOWAIT); + if (ret >= 0) { + id = ret; + ret = 0; + } else { + id = KSMBD_NO_FID; + fd_limit_close(); + } + + __open_id_set(fp, id, type); + write_unlock(&ft->lock); + idr_preload_end(); + return ret; +} + +unsigned int ksmbd_open_durable_fd(struct ksmbd_file *fp) +{ + __open_id(&global_ft, fp, OPEN_ID_TYPE_PERSISTENT_ID); + return fp->persistent_id; +} + +struct ksmbd_file *ksmbd_open_fd(struct ksmbd_work *work, struct file *filp) +{ + struct ksmbd_file *fp; + int ret; + + fp = kmem_cache_zalloc(filp_cache, GFP_KERNEL); + if (!fp) { + pr_err("Failed to allocate memory\n"); + return ERR_PTR(-ENOMEM); + } + + INIT_LIST_HEAD(&fp->blocked_works); + INIT_LIST_HEAD(&fp->node); + INIT_LIST_HEAD(&fp->lock_list); + spin_lock_init(&fp->f_lock); + atomic_set(&fp->refcount, 1); + + fp->filp = filp; + fp->conn = work->conn; + fp->tcon = work->tcon; + fp->volatile_id = KSMBD_NO_FID; + fp->persistent_id = KSMBD_NO_FID; + fp->f_ci = ksmbd_inode_get(fp); + + if (!fp->f_ci) { + ret = -ENOMEM; + goto err_out; + } + + ret = __open_id(&work->sess->file_table, fp, OPEN_ID_TYPE_VOLATILE_ID); + if (ret) { + ksmbd_inode_put(fp->f_ci); + goto err_out; + } + + atomic_inc(&work->conn->stats.open_files_count); + return fp; + +err_out: + kmem_cache_free(filp_cache, fp); + return ERR_PTR(ret); +} + +static int +__close_file_table_ids(struct ksmbd_file_table *ft, + struct ksmbd_tree_connect *tcon, + bool (*skip)(struct ksmbd_tree_connect *tcon, + struct ksmbd_file *fp)) +{ + unsigned int id; + struct ksmbd_file *fp; + int num = 0; + + idr_for_each_entry(ft->idr, fp, id) { + if (skip(tcon, fp)) + continue; + + set_close_state_blocked_works(fp); + + if (!atomic_dec_and_test(&fp->refcount)) + continue; + __ksmbd_close_fd(ft, fp); + num++; + } + return num; +} + +static bool tree_conn_fd_check(struct ksmbd_tree_connect *tcon, + struct ksmbd_file *fp) +{ + return fp->tcon != tcon; +} + +static bool session_fd_check(struct ksmbd_tree_connect *tcon, + struct ksmbd_file *fp) +{ + return false; +} + +void ksmbd_close_tree_conn_fds(struct ksmbd_work *work) +{ + int num = __close_file_table_ids(&work->sess->file_table, + work->tcon, + tree_conn_fd_check); + + atomic_sub(num, &work->conn->stats.open_files_count); +} + +void ksmbd_close_session_fds(struct ksmbd_work *work) +{ + int num = __close_file_table_ids(&work->sess->file_table, + work->tcon, + session_fd_check); + + atomic_sub(num, &work->conn->stats.open_files_count); +} + +int ksmbd_init_global_file_table(void) +{ + return ksmbd_init_file_table(&global_ft); +} + +void ksmbd_free_global_file_table(void) +{ + struct ksmbd_file *fp = NULL; + unsigned int id; + + idr_for_each_entry(global_ft.idr, fp, id) { + __ksmbd_remove_durable_fd(fp); + kmem_cache_free(filp_cache, fp); + } + + ksmbd_destroy_file_table(&global_ft); +} + +int ksmbd_init_file_table(struct ksmbd_file_table *ft) +{ + ft->idr = kzalloc(sizeof(struct idr), GFP_KERNEL); + if (!ft->idr) + return -ENOMEM; + + idr_init(ft->idr); + rwlock_init(&ft->lock); + return 0; +} + +void ksmbd_destroy_file_table(struct ksmbd_file_table *ft) +{ + if (!ft->idr) + return; + + __close_file_table_ids(ft, NULL, session_fd_check); + idr_destroy(ft->idr); + kfree(ft->idr); + ft->idr = NULL; +} + +int ksmbd_init_file_cache(void) +{ + filp_cache = kmem_cache_create("ksmbd_file_cache", + sizeof(struct ksmbd_file), 0, + SLAB_HWCACHE_ALIGN, NULL); + if (!filp_cache) + goto out; + + return 0; + +out: + pr_err("failed to allocate file cache\n"); + return -ENOMEM; +} + +void ksmbd_exit_file_cache(void) +{ + kmem_cache_destroy(filp_cache); +} |