Merge tag 'for-6.15/io_uring-20250322' of git://git.kernel.dk/linux

Pull io_uring updates from Jens Axboe:
 "This is the first of the io_uring pull requests for the 6.15 merge
  window, there will be others once the net tree has gone in. This
  contains:

   - Cleanup and unification of cancelation handling across various
     request types.

   - Improvement for bundles, supporting them both for incrementally
     consumed buffers, and for non-multishot requests.

   - Enable toggling of using iowait while waiting on io_uring events or
     not. Unfortunately this is still tied with CPU frequency boosting
     on short waits, as the scheduler side has not been very receptive
     to splitting the (useless) iowait stat from the cpufreq implied
     boost.

   - Add support for kbuf nodes, enabling zero-copy support for the ublk
     block driver.

   - Various cleanups for resource node handling.

   - Series greatly cleaning up the legacy provided (non-ring based)
     buffers. For years, we've been pushing the ring provided buffers as
     the way to go, and that is what people have been using. Reduce the
     complexity and code associated with legacy provided buffers.

   - Series cleaning up the compat handling.

   - Series improving and cleaning up the recvmsg/sendmsg iovec and msg
     handling.

   - Series of cleanups for io-wq.

   - Start adding a bunch of selftests. The liburing repository
     generally carries feature and regression tests for everything, but
     at least for ublk initially, we'll try and go the route of having
     it in selftests as well. We'll see how this goes, might decide to
     migrate more tests this way in the future.

   - Various little cleanups and fixes"

* tag 'for-6.15/io_uring-20250322' of git://git.kernel.dk/linux: (108 commits)
  selftests: ublk: add stripe target
  selftests: ublk: simplify loop io completion
  selftests: ublk: enable zero copy for null target
  selftests: ublk: prepare for supporting stripe target
  selftests: ublk: move common code into common.c
  selftests: ublk: increase max buffer size to 1MB
  selftests: ublk: add single sqe allocator helper
  selftests: ublk: add generic_01 for verifying sequential IO order
  selftests: ublk: fix starting ublk device
  io_uring: enable toggle of iowait usage when waiting on CQEs
  selftests: ublk: fix write cache implementation
  selftests: ublk: add variable for user to not show test result
  selftests: ublk: don't show `modprobe` failure
  selftests: ublk: add one dependency header
  io_uring/kbuf: enable bundles for incrementally consumed buffers
  Revert "io_uring/rsrc: simplify the bvec iter count calculation"
  selftests: ublk: improve test usability
  selftests: ublk: add stress test for covering IO vs. killing ublk server
  selftests: ublk: add one stress test for covering IO vs. removing device
  selftests: ublk: load/unload ublk_drv when preparing & cleaning up tests
  ...

2 files changed, 29 insertions, 8 deletions

diff --git a/include/linux/io_uring/cmd.h b/include/linux/io_uring/cmd.h
index abd0c8bd950b..598cacda4aa3 100644
--- a/include/linux/io_uring/cmd.h
+++ b/include/linux/io_uring/cmd.h
@@ -4,6 +4,7 @@
 
 #include <uapi/linux/io_uring.h>
 #include <linux/io_uring_types.h>
+#include <linux/blk-mq.h>
 
 /* only top 8 bits of sqe->uring_cmd_flags for kernel internal use */
 #define IORING_URING_CMD_CANCELABLE	(1U << 30)
@@ -39,7 +40,9 @@ static inline void io_uring_cmd_private_sz_check(size_t cmd_sz)
 
 #if defined(CONFIG_IO_URING)
 int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
-			      struct iov_iter *iter, void *ioucmd);
+			      struct iov_iter *iter,
+			      struct io_uring_cmd *ioucmd,
+			      unsigned int issue_flags);
 
 /*
  * Completes the request, i.e. posts an io_uring CQE and deallocates @ioucmd
@@ -66,8 +69,10 @@ void io_uring_cmd_mark_cancelable(struct io_uring_cmd *cmd,
 void io_uring_cmd_issue_blocking(struct io_uring_cmd *ioucmd);
 
 #else
-static inline int io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
-			      struct iov_iter *iter, void *ioucmd)
+static inline int
+io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
+			  struct iov_iter *iter, struct io_uring_cmd *ioucmd,
+			  unsigned int issue_flags)
 {
 	return -EOPNOTSUPP;
 }
@@ -123,4 +128,10 @@ static inline struct io_uring_cmd_data *io_uring_cmd_get_async_data(struct io_ur
 	return cmd_to_io_kiocb(cmd)->async_data;
 }
 
+int io_buffer_register_bvec(struct io_uring_cmd *cmd, struct request *rq,
+			    void (*release)(void *), unsigned int index,
+			    unsigned int issue_flags);
+int io_buffer_unregister_bvec(struct io_uring_cmd *cmd, unsigned int index,
+			      unsigned int issue_flags);
+
 #endif /* _LINUX_IO_URING_CMD_H */
diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h
index 3def525a1da3..72aac84dca93 100644
--- a/include/linux/io_uring_types.h
+++ b/include/linux/io_uring_types.h
@@ -292,6 +292,8 @@ struct io_ring_ctx {
 
 		struct io_file_table	file_table;
 		struct io_rsrc_data	buf_table;
+		struct io_alloc_cache	node_cache;
+		struct io_alloc_cache	imu_cache;
 
 		struct io_submit_state	submit_state;
 
@@ -360,7 +362,6 @@ struct io_ring_ctx {
 
 	spinlock_t		completion_lock;
 
-	struct list_head	io_buffers_comp;
 	struct list_head	cq_overflow_list;
 
 	struct hlist_head	waitid_list;
@@ -379,8 +380,6 @@ struct io_ring_ctx {
 	unsigned int		file_alloc_start;
 	unsigned int		file_alloc_end;
 
-	struct list_head	io_buffers_cache;
-
 	/* Keep this last, we don't need it for the fast path */
 	struct wait_queue_head		poll_wq;
 	struct io_restriction		restrictions;
@@ -439,8 +438,15 @@ struct io_ring_ctx {
 	struct io_mapped_region		param_region;
 };
 
+/*
+ * Token indicating function is called in task work context:
+ * ctx->uring_lock is held and any completions generated will be flushed.
+ * ONLY core io_uring.c should instantiate this struct.
+ */
 struct io_tw_state {
 };
+/* Alias to use in code that doesn't instantiate struct io_tw_state */
+typedef struct io_tw_state io_tw_token_t;
 
 enum {
 	REQ_F_FIXED_FILE_BIT	= IOSQE_FIXED_FILE_BIT,
@@ -566,7 +572,7 @@ enum {
 	REQ_F_HAS_METADATA	= IO_REQ_FLAG(REQ_F_HAS_METADATA_BIT),
 };
 
-typedef void (*io_req_tw_func_t)(struct io_kiocb *req, struct io_tw_state *ts);
+typedef void (*io_req_tw_func_t)(struct io_kiocb *req, io_tw_token_t tw);
 
 struct io_task_work {
 	struct llist_node		node;
@@ -601,7 +607,11 @@ static inline void io_kiocb_cmd_sz_check(size_t cmd_sz)
 	io_kiocb_cmd_sz_check(sizeof(cmd_type)) , \
 	((cmd_type *)&(req)->cmd) \
 )
-#define cmd_to_io_kiocb(ptr)	((struct io_kiocb *) ptr)
+
+static inline struct io_kiocb *cmd_to_io_kiocb(void *ptr)
+{
+	return ptr;
+}
 
 struct io_kiocb {
 	union {