Merge tag 'for-6.15/io_uring-reg-vec-20250327' of git://git.kernel.dk/linux

Pull more io_uring updates from Jens Axboe:
 "Final separate updates for io_uring.

  This started out as a series of cleanups improvements and improvements
  for registered buffers, but as the last series of the io_uring changes
  for 6.15, it also collected a few fixes for the other branches on top:

   - Add support for vectored fixed/registered buffers.

     Previously only single segments have been supported for commands,
     now vectored variants are supported as well. This series includes
     networking and file read/write support.

   - Small series unifying return codes across multi and single shot.

   - Small series cleaning up registerd buffer importing.

   - Adding support for vectored registered buffers for uring_cmd.

   - Fix for io-wq handling of command reissue.

   - Various little fixes and tweaks"

* tag 'for-6.15/io_uring-reg-vec-20250327' of git://git.kernel.dk/linux: (25 commits)
  io_uring/net: fix io_req_post_cqe abuse by send bundle
  io_uring/net: use REQ_F_IMPORT_BUFFER for send_zc
  io_uring: move min_events sanitisation
  io_uring: rename "min" arg in io_iopoll_check()
  io_uring: open code __io_post_aux_cqe()
  io_uring: defer iowq cqe overflow via task_work
  io_uring: fix retry handling off iowq
  io_uring/net: only import send_zc buffer once
  io_uring/cmd: introduce io_uring_cmd_import_fixed_vec
  io_uring/cmd: add iovec cache for commands
  io_uring/cmd: don't expose entire cmd async data
  io_uring: rename the data cmd cache
  io_uring: rely on io_prep_reg_vec for iovec placement
  io_uring: introduce io_prep_reg_iovec()
  io_uring: unify STOP_MULTISHOT with IOU_OK
  io_uring: return -EAGAIN to continue multishot
  io_uring: cap cached iovec/bvec size
  io_uring/net: implement vectored reg bufs for zctx
  io_uring/net: convert to struct iou_vec
  io_uring/net: pull vec alloc out of msghdr import
  ...

2 files changed, 31 insertions, 1 deletions

diff --git a/include/linux/io_uring/cmd.h b/include/linux/io_uring/cmd.h
index 598cacda4aa3..e6723fa95160 100644
--- a/include/linux/io_uring/cmd.h
+++ b/include/linux/io_uring/cmd.h
@@ -43,6 +43,11 @@ 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);
+int io_uring_cmd_import_fixed_vec(struct io_uring_cmd *ioucmd,
+				  const struct iovec __user *uvec,
+				  size_t uvec_segs,
+				  int ddir, struct iov_iter *iter,
+				  unsigned issue_flags);
 
 /*
  * Completes the request, i.e. posts an io_uring CQE and deallocates @ioucmd
@@ -76,6 +81,14 @@ io_uring_cmd_import_fixed(u64 ubuf, unsigned long len, int rw,
 {
 	return -EOPNOTSUPP;
 }
+static inline int io_uring_cmd_import_fixed_vec(struct io_uring_cmd *ioucmd,
+						const struct iovec __user *uvec,
+						size_t uvec_segs,
+						int ddir, struct iov_iter *iter,
+						unsigned issue_flags)
+{
+	return -EOPNOTSUPP;
+}
 static inline void io_uring_cmd_done(struct io_uring_cmd *cmd, ssize_t ret,
 		u64 ret2, unsigned issue_flags)
 {
diff --git a/include/linux/io_uring_types.h b/include/linux/io_uring_types.h
index 35fc241c4672..b44d201520d8 100644
--- a/include/linux/io_uring_types.h
+++ b/include/linux/io_uring_types.h
@@ -110,6 +110,14 @@ struct io_uring_task {
 	} ____cacheline_aligned_in_smp;
 };
 
+struct iou_vec {
+	union {
+		struct iovec	*iovec;
+		struct bio_vec	*bvec;
+	};
+	unsigned		nr; /* number of struct iovec it can hold */
+};
+
 struct io_uring {
 	u32 head;
 	u32 tail;
@@ -310,7 +318,7 @@ struct io_ring_ctx {
 		struct io_alloc_cache	apoll_cache;
 		struct io_alloc_cache	netmsg_cache;
 		struct io_alloc_cache	rw_cache;
-		struct io_alloc_cache	uring_cache;
+		struct io_alloc_cache	cmd_cache;
 
 		/*
 		 * Any cancelable uring_cmd is added to this list in
@@ -482,6 +490,7 @@ enum {
 	REQ_F_SKIP_LINK_CQES_BIT,
 	REQ_F_SINGLE_POLL_BIT,
 	REQ_F_DOUBLE_POLL_BIT,
+	REQ_F_MULTISHOT_BIT,
 	REQ_F_APOLL_MULTISHOT_BIT,
 	REQ_F_CLEAR_POLLIN_BIT,
 	/* keep async read/write and isreg together and in order */
@@ -494,6 +503,7 @@ enum {
 	REQ_F_BUFFERS_COMMIT_BIT,
 	REQ_F_BUF_NODE_BIT,
 	REQ_F_HAS_METADATA_BIT,
+	REQ_F_IMPORT_BUFFER_BIT,
 
 	/* not a real bit, just to check we're not overflowing the space */
 	__REQ_F_LAST_BIT,
@@ -558,6 +568,8 @@ enum {
 	REQ_F_SINGLE_POLL	= IO_REQ_FLAG(REQ_F_SINGLE_POLL_BIT),
 	/* double poll may active */
 	REQ_F_DOUBLE_POLL	= IO_REQ_FLAG(REQ_F_DOUBLE_POLL_BIT),
+	/* request posts multiple completions, should be set at prep time */
+	REQ_F_MULTISHOT		= IO_REQ_FLAG(REQ_F_MULTISHOT_BIT),
 	/* fast poll multishot mode */
 	REQ_F_APOLL_MULTISHOT	= IO_REQ_FLAG(REQ_F_APOLL_MULTISHOT_BIT),
 	/* recvmsg special flag, clear EPOLLIN */
@@ -576,6 +588,11 @@ enum {
 	REQ_F_BUF_NODE		= IO_REQ_FLAG(REQ_F_BUF_NODE_BIT),
 	/* request has read/write metadata assigned */
 	REQ_F_HAS_METADATA	= IO_REQ_FLAG(REQ_F_HAS_METADATA_BIT),
+	/*
+	 * For vectored fixed buffers, resolve iovec to registered buffers.
+	 * For SEND_ZC, whether to import buffers (i.e. the first issue).
+	 */
+	REQ_F_IMPORT_BUFFER	= IO_REQ_FLAG(REQ_F_IMPORT_BUFFER_BIT),
 };
 
 typedef void (*io_req_tw_func_t)(struct io_kiocb *req, io_tw_token_t tw);