io_uring: move uring_cmd handling to its own file

Signed-off-by: Jens Axboe <axboe@kernel.dk>

io_uring/Makefile

@@ -4,5 +4,5 @@
 
 obj-$(CONFIG_IO_URING)		+= io_uring.o xattr.o nop.o fs.o splice.o \
 					sync.o advise.o filetable.o \
-					openclose.o
+					openclose.o uring_cmd.o
 obj-$(CONFIG_IO_WQ)		+= io-wq.o

io_uring/io_uring.c

@@ -99,6 +99,7 @@
 #include "sync.h"
 #include "advise.h"
 #include "openclose.h"
+#include "uring_cmd.h"
 
 #define IORING_MAX_ENTRIES	32768
 #define IORING_MAX_CQ_ENTRIES	(2 * IORING_MAX_ENTRIES)
@@ -473,14 +474,6 @@ struct io_cancel_data {
 	int seq;
 };
 
-/*
- * The URING_CMD payload starts at 'cmd' in the first sqe, and continues into
- * the following sqe if SQE128 is used.
- */
-#define uring_cmd_pdu_size(is_sqe128)				\
-	((1 + !!(is_sqe128)) * sizeof(struct io_uring_sqe) -	\
-		offsetof(struct io_uring_sqe, cmd))
-
 struct io_op_def {
 	/* needs req->file assigned */
 	unsigned		needs_file : 1;
@@ -988,11 +981,6 @@ static bool io_match_task_safe(struct io_kiocb *head, struct task_struct *task,
 	return matched;
 }
 
-static inline bool req_has_async_data(struct io_kiocb *req)
-{
-	return req->flags & REQ_F_ASYNC_DATA;
-}
-
 static inline void req_fail_link_node(struct io_kiocb *req, int res)
 {
 	req_set_fail(req);
@@ -1743,7 +1731,7 @@ static void io_req_complete_post(struct io_kiocb *req)
 	io_cqring_ev_posted(ctx);
 }
 
-static inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags)
+inline void __io_req_complete(struct io_kiocb *req, unsigned issue_flags)
 {
 	if (issue_flags & IO_URING_F_COMPLETE_DEFER)
 		req->flags |= REQ_F_COMPLETE_INLINE;
@@ -2151,7 +2139,7 @@ static void __io_req_task_work_add(struct io_kiocb *req,
 	}
 }
 
-static void io_req_task_work_add(struct io_kiocb *req)
+void io_req_task_work_add(struct io_kiocb *req)
 {
 	struct io_uring_task *tctx = req->task->io_uring;
 
@@ -3268,7 +3256,7 @@ static void io_req_map_rw(struct io_kiocb *req, const struct iovec *iovec,
 	}
 }
 
-static inline bool io_alloc_async_data(struct io_kiocb *req)
+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);
@@ -3714,111 +3702,6 @@ out_free:
 	return ret;
 }
 
-static void io_uring_cmd_work(struct io_kiocb *req, bool *locked)
-{
-	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req);
-
-	ioucmd->task_work_cb(ioucmd);
-}
-
-void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
-			void (*task_work_cb)(struct io_uring_cmd *))
-{
-	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
-
-	ioucmd->task_work_cb = task_work_cb;
-	req->io_task_work.func = io_uring_cmd_work;
-	io_req_task_work_add(req);
-}
-EXPORT_SYMBOL_GPL(io_uring_cmd_complete_in_task);
-
-static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
-					  u64 extra1, u64 extra2)
-{
-	req->extra1 = extra1;
-	req->extra2 = extra2;
-	req->flags |= REQ_F_CQE32_INIT;
-}
-
-/*
- * Called by consumers of io_uring_cmd, if they originally returned
- * -EIOCBQUEUED upon receiving the command.
- */
-void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2)
-{
-	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
-
-	if (ret < 0)
-		req_set_fail(req);
-
-	io_req_set_res(req, 0, ret);
-	if (req->ctx->flags & IORING_SETUP_CQE32)
-		io_req_set_cqe32_extra(req, res2, 0);
-	__io_req_complete(req, 0);
-}
-EXPORT_SYMBOL_GPL(io_uring_cmd_done);
-
-static int io_uring_cmd_prep_async(struct io_kiocb *req)
-{
-	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req);
-	size_t cmd_size;
-
-	cmd_size = uring_cmd_pdu_size(req->ctx->flags & IORING_SETUP_SQE128);
-
-	memcpy(req->async_data, ioucmd->cmd, cmd_size);
-	return 0;
-}
-
-static int io_uring_cmd_prep(struct io_kiocb *req,
-			     const struct io_uring_sqe *sqe)
-{
-	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req);
-
-	if (sqe->rw_flags || sqe->__pad1)
-		return -EINVAL;
-	ioucmd->cmd = sqe->cmd;
-	ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
-	return 0;
-}
-
-static int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
-{
-	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req);
-	struct io_ring_ctx *ctx = req->ctx;
-	struct file *file = req->file;
-	int ret;
-
-	if (!req->file->f_op->uring_cmd)
-		return -EOPNOTSUPP;
-
-	if (ctx->flags & IORING_SETUP_SQE128)
-		issue_flags |= IO_URING_F_SQE128;
-	if (ctx->flags & IORING_SETUP_CQE32)
-		issue_flags |= IO_URING_F_CQE32;
-	if (ctx->flags & IORING_SETUP_IOPOLL)
-		issue_flags |= IO_URING_F_IOPOLL;
-
-	if (req_has_async_data(req))
-		ioucmd->cmd = req->async_data;
-
-	ret = file->f_op->uring_cmd(ioucmd, issue_flags);
-	if (ret == -EAGAIN) {
-		if (!req_has_async_data(req)) {
-			if (io_alloc_async_data(req))
-				return -ENOMEM;
-			io_uring_cmd_prep_async(req);
-		}
-		return -EAGAIN;
-	}
-
-	if (ret != -EIOCBQUEUED) {
-		io_uring_cmd_done(ioucmd, ret, 0);
-		return IOU_OK;
-	}
-
-	return IOU_ISSUE_SKIP_COMPLETE;
-}
-
 static int io_msg_ring_prep(struct io_kiocb *req,
 			    const struct io_uring_sqe *sqe)
 {
@@ -11533,8 +11416,6 @@ static int __init io_uring_init(void)
 
 	BUILD_BUG_ON(sizeof(atomic_t) != sizeof(u32));
 
-	BUILD_BUG_ON(sizeof(struct io_uring_cmd) > 64);
-
 	for (i = 0; i < ARRAY_SIZE(io_op_defs); i++) {
 		BUG_ON(!io_op_defs[i].prep);
 		BUG_ON(!io_op_defs[i].issue);

io_uring/io_uring.h

@@ -25,6 +25,11 @@ static inline void io_req_set_res(struct io_kiocb *req, s32 res, u32 cflags)
 	req->cqe.flags = cflags;
 }
 
+static inline bool req_has_async_data(struct io_kiocb *req)
+{
+	return req->flags & REQ_F_ASYNC_DATA;
+}
+
 static inline void io_put_file(struct file *file)
 {
 	if (file)
@@ -53,6 +58,8 @@ static inline void io_ring_submit_lock(struct io_ring_ctx *ctx,
 	lockdep_assert_held(&ctx->uring_lock);
 }
 
+void __io_req_complete(struct io_kiocb *req, unsigned issue_flags);
+
 struct file *io_file_get_normal(struct io_kiocb *req, int fd);
 struct file *io_file_get_fixed(struct io_kiocb *req, int fd,
 			       unsigned issue_flags);
@@ -65,5 +72,7 @@ int io_queue_rsrc_removal(struct io_rsrc_data *data, unsigned idx,
 void io_rsrc_node_switch(struct io_ring_ctx *ctx,
 			 struct io_rsrc_data *data_to_kill);
 bool io_is_uring_fops(struct file *file);
+bool io_alloc_async_data(struct io_kiocb *req);
+void io_req_task_work_add(struct io_kiocb *req);
 
 #endif

io_uring/uring_cmd.c

@@ -0,0 +1,115 @@
+// SPDX-License-Identifier: GPL-2.0
+#include <linux/kernel.h>
+#include <linux/errno.h>
+#include <linux/file.h>
+#include <linux/io_uring.h>
+
+#include <uapi/linux/io_uring.h>
+
+#include "io_uring_types.h"
+#include "io_uring.h"
+#include "uring_cmd.h"
+
+static void io_uring_cmd_work(struct io_kiocb *req, bool *locked)
+{
+	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req);
+
+	ioucmd->task_work_cb(ioucmd);
+}
+
+void io_uring_cmd_complete_in_task(struct io_uring_cmd *ioucmd,
+			void (*task_work_cb)(struct io_uring_cmd *))
+{
+	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
+
+	ioucmd->task_work_cb = task_work_cb;
+	req->io_task_work.func = io_uring_cmd_work;
+	io_req_task_work_add(req);
+}
+EXPORT_SYMBOL_GPL(io_uring_cmd_complete_in_task);
+
+static inline void io_req_set_cqe32_extra(struct io_kiocb *req,
+					  u64 extra1, u64 extra2)
+{
+	req->extra1 = extra1;
+	req->extra2 = extra2;
+	req->flags |= REQ_F_CQE32_INIT;
+}
+
+/*
+ * Called by consumers of io_uring_cmd, if they originally returned
+ * -EIOCBQUEUED upon receiving the command.
+ */
+void io_uring_cmd_done(struct io_uring_cmd *ioucmd, ssize_t ret, ssize_t res2)
+{
+	struct io_kiocb *req = cmd_to_io_kiocb(ioucmd);
+
+	if (ret < 0)
+		req_set_fail(req);
+
+	io_req_set_res(req, 0, ret);
+	if (req->ctx->flags & IORING_SETUP_CQE32)
+		io_req_set_cqe32_extra(req, res2, 0);
+	__io_req_complete(req, 0);
+}
+EXPORT_SYMBOL_GPL(io_uring_cmd_done);
+
+int io_uring_cmd_prep_async(struct io_kiocb *req)
+{
+	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req);
+	size_t cmd_size;
+
+	cmd_size = uring_cmd_pdu_size(req->ctx->flags & IORING_SETUP_SQE128);
+
+	memcpy(req->async_data, ioucmd->cmd, cmd_size);
+	return 0;
+}
+
+int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
+{
+	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req);
+
+	if (sqe->rw_flags || sqe->__pad1)
+		return -EINVAL;
+	ioucmd->cmd = sqe->cmd;
+	ioucmd->cmd_op = READ_ONCE(sqe->cmd_op);
+	return 0;
+}
+
+int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags)
+{
+	struct io_uring_cmd *ioucmd = io_kiocb_to_cmd(req);
+	struct io_ring_ctx *ctx = req->ctx;
+	struct file *file = req->file;
+	int ret;
+
+	if (!req->file->f_op->uring_cmd)
+		return -EOPNOTSUPP;
+
+	if (ctx->flags & IORING_SETUP_SQE128)
+		issue_flags |= IO_URING_F_SQE128;
+	if (ctx->flags & IORING_SETUP_CQE32)
+		issue_flags |= IO_URING_F_CQE32;
+	if (ctx->flags & IORING_SETUP_IOPOLL)
+		issue_flags |= IO_URING_F_IOPOLL;
+
+	if (req_has_async_data(req))
+		ioucmd->cmd = req->async_data;
+
+	ret = file->f_op->uring_cmd(ioucmd, issue_flags);
+	if (ret == -EAGAIN) {
+		if (!req_has_async_data(req)) {
+			if (io_alloc_async_data(req))
+				return -ENOMEM;
+			io_uring_cmd_prep_async(req);
+		}
+		return -EAGAIN;
+	}
+
+	if (ret != -EIOCBQUEUED) {
+		io_uring_cmd_done(ioucmd, ret, 0);
+		return IOU_OK;
+	}
+
+	return IOU_ISSUE_SKIP_COMPLETE;
+}

io_uring/uring_cmd.h

@@ -0,0 +1,13 @@
+// SPDX-License-Identifier: GPL-2.0
+
+int io_uring_cmd(struct io_kiocb *req, unsigned int issue_flags);
+int io_uring_cmd_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
+int io_uring_cmd_prep_async(struct io_kiocb *req);
+
+/*
+ * The URING_CMD payload starts at 'cmd' in the first sqe, and continues into
+ * the following sqe if SQE128 is used.
+ */
+#define uring_cmd_pdu_size(is_sqe128)				\
+	((1 + !!(is_sqe128)) * sizeof(struct io_uring_sqe) -	\
+		offsetof(struct io_uring_sqe, cmd))