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From: Jens Axboe <[email protected]>
To: [email protected]
Cc: Jens Axboe <[email protected]>
Subject: [PATCH 1/4] io_uring: check IOPOLL/ioprio support upfront
Date: Tue, 26 Apr 2022 12:33:40 -0600	[thread overview]
Message-ID: <[email protected]> (raw)
In-Reply-To: <[email protected]>

Don't punt this check to the op prep handlers, add the support to
io_op_defs and we can check them while setting up the request.

This reduces the text size by 500 bytes on aarch64, and makes this less
fragile by having the check in one spot and needing opcodes to opt in
to IOPOLL or ioprio support.

Signed-off-by: Jens Axboe <[email protected]>
---
 fs/io_uring.c | 150 +++++++++++++++++---------------------------------
 1 file changed, 52 insertions(+), 98 deletions(-)

diff --git a/fs/io_uring.c b/fs/io_uring.c
index 1e7466079af7..29153958ea78 100644
--- a/fs/io_uring.c
+++ b/fs/io_uring.c
@@ -1028,6 +1028,10 @@ struct io_op_def {
 	unsigned		not_supported : 1;
 	/* skip auditing */
 	unsigned		audit_skip : 1;
+	/* supports ioprio */
+	unsigned		ioprio : 1;
+	/* supports iopoll */
+	unsigned		iopoll : 1;
 	/* size of async data needed, if any */
 	unsigned short		async_size;
 };
@@ -1042,6 +1046,8 @@ static const struct io_op_def io_op_defs[] = {
 		.needs_async_setup	= 1,
 		.plug			= 1,
 		.audit_skip		= 1,
+		.ioprio			= 1,
+		.iopoll			= 1,
 		.async_size		= sizeof(struct io_async_rw),
 	},
 	[IORING_OP_WRITEV] = {
@@ -1052,6 +1058,8 @@ static const struct io_op_def io_op_defs[] = {
 		.needs_async_setup	= 1,
 		.plug			= 1,
 		.audit_skip		= 1,
+		.ioprio			= 1,
+		.iopoll			= 1,
 		.async_size		= sizeof(struct io_async_rw),
 	},
 	[IORING_OP_FSYNC] = {
@@ -1064,6 +1072,8 @@ static const struct io_op_def io_op_defs[] = {
 		.pollin			= 1,
 		.plug			= 1,
 		.audit_skip		= 1,
+		.ioprio			= 1,
+		.iopoll			= 1,
 		.async_size		= sizeof(struct io_async_rw),
 	},
 	[IORING_OP_WRITE_FIXED] = {
@@ -1073,6 +1083,8 @@ static const struct io_op_def io_op_defs[] = {
 		.pollout		= 1,
 		.plug			= 1,
 		.audit_skip		= 1,
+		.ioprio			= 1,
+		.iopoll			= 1,
 		.async_size		= sizeof(struct io_async_rw),
 	},
 	[IORING_OP_POLL_ADD] = {
@@ -1137,6 +1149,7 @@ static const struct io_op_def io_op_defs[] = {
 	[IORING_OP_CLOSE] = {},
 	[IORING_OP_FILES_UPDATE] = {
 		.audit_skip		= 1,
+		.iopoll			= 1,
 	},
 	[IORING_OP_STATX] = {
 		.audit_skip		= 1,
@@ -1148,6 +1161,8 @@ static const struct io_op_def io_op_defs[] = {
 		.buffer_select		= 1,
 		.plug			= 1,
 		.audit_skip		= 1,
+		.ioprio			= 1,
+		.iopoll			= 1,
 		.async_size		= sizeof(struct io_async_rw),
 	},
 	[IORING_OP_WRITE] = {
@@ -1157,6 +1172,8 @@ static const struct io_op_def io_op_defs[] = {
 		.pollout		= 1,
 		.plug			= 1,
 		.audit_skip		= 1,
+		.ioprio			= 1,
+		.iopoll			= 1,
 		.async_size		= sizeof(struct io_async_rw),
 	},
 	[IORING_OP_FADVISE] = {
@@ -1191,9 +1208,11 @@ static const struct io_op_def io_op_defs[] = {
 	},
 	[IORING_OP_PROVIDE_BUFFERS] = {
 		.audit_skip		= 1,
+		.iopoll			= 1,
 	},
 	[IORING_OP_REMOVE_BUFFERS] = {
 		.audit_skip		= 1,
+		.iopoll			= 1,
 	},
 	[IORING_OP_TEE] = {
 		.needs_file		= 1,
@@ -1211,6 +1230,7 @@ static const struct io_op_def io_op_defs[] = {
 	[IORING_OP_LINKAT] = {},
 	[IORING_OP_MSG_RING] = {
 		.needs_file		= 1,
+		.iopoll			= 1,
 	},
 };
 
@@ -4139,9 +4159,7 @@ static int io_renameat_prep(struct io_kiocb *req,
 	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)
+	if (sqe->buf_index || sqe->splice_fd_in)
 		return -EINVAL;
 	if (unlikely(req->flags & REQ_F_FIXED_FILE))
 		return -EBADF;
@@ -4190,10 +4208,7 @@ static int io_unlinkat_prep(struct io_kiocb *req,
 	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)
+	if (sqe->off || sqe->len || sqe->buf_index || sqe->splice_fd_in)
 		return -EINVAL;
 	if (unlikely(req->flags & REQ_F_FIXED_FILE))
 		return -EBADF;
@@ -4239,10 +4254,7 @@ static int io_mkdirat_prep(struct io_kiocb *req,
 	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)
+	if (sqe->off || sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
 		return -EINVAL;
 	if (unlikely(req->flags & REQ_F_FIXED_FILE))
 		return -EBADF;
@@ -4282,10 +4294,7 @@ static int io_symlinkat_prep(struct io_kiocb *req,
 	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)
+	if (sqe->len || sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
 		return -EINVAL;
 	if (unlikely(req->flags & REQ_F_FIXED_FILE))
 		return -EBADF;
@@ -4331,9 +4340,7 @@ static int io_linkat_prep(struct io_kiocb *req,
 	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)
+	if (sqe->rw_flags || sqe->buf_index || sqe->splice_fd_in)
 		return -EINVAL;
 	if (unlikely(req->flags & REQ_F_FIXED_FILE))
 		return -EBADF;
@@ -4380,9 +4387,7 @@ 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 ||
+	if (unlikely(sqe->off || sqe->addr || sqe->rw_flags ||
 		     sqe->buf_index || sqe->splice_fd_in))
 		return -EINVAL;
 
@@ -4422,9 +4427,6 @@ static int __io_splice_prep(struct io_kiocb *req,
 	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->len = READ_ONCE(sqe->len);
 	sp->flags = READ_ONCE(sqe->splice_flags);
 	if (unlikely(sp->flags & ~valid_flags))
@@ -4523,11 +4525,6 @@ static int io_splice(struct io_kiocb *req, unsigned int issue_flags)
  */
 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;
 }
@@ -4535,8 +4532,8 @@ static int io_nop(struct io_kiocb *req, unsigned int issue_flags)
 static int io_msg_ring_prep(struct io_kiocb *req,
 			    const struct io_uring_sqe *sqe)
 {
-	if (unlikely(sqe->addr || sqe->ioprio || sqe->rw_flags ||
-		     sqe->splice_fd_in || sqe->buf_index || sqe->personality))
+	if (unlikely(sqe->addr || sqe->rw_flags || sqe->splice_fd_in ||
+		     sqe->buf_index || sqe->personality))
 		return -EINVAL;
 
 	req->msg.user_data = READ_ONCE(sqe->off);
@@ -4577,12 +4574,7 @@ static int io_msg_ring(struct io_kiocb *req, unsigned int issue_flags)
 
 static int io_fsync_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))
+	if (unlikely(sqe->addr || sqe->buf_index || sqe->splice_fd_in))
 		return -EINVAL;
 
 	req->sync.flags = READ_ONCE(sqe->fsync_flags);
@@ -4615,10 +4607,7 @@ static int io_fsync(struct io_kiocb *req, unsigned int issue_flags)
 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))
+	if (sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
 		return -EINVAL;
 
 	req->sync.off = READ_ONCE(sqe->off);
@@ -4649,9 +4638,7 @@ 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))
+	if (unlikely(sqe->buf_index))
 		return -EINVAL;
 	if (unlikely(req->flags & REQ_F_FIXED_FILE))
 		return -EBADF;
@@ -4783,7 +4770,7 @@ static int io_remove_buffers_prep(struct io_kiocb *req,
 	struct io_provide_buf *p = &req->pbuf;
 	u64 tmp;
 
-	if (sqe->ioprio || sqe->rw_flags || sqe->addr || sqe->len || sqe->off ||
+	if (sqe->rw_flags || sqe->addr || sqe->len || sqe->off ||
 	    sqe->splice_fd_in)
 		return -EINVAL;
 
@@ -4850,7 +4837,7 @@ static int io_provide_buffers_prep(struct io_kiocb *req,
 	struct io_provide_buf *p = &req->pbuf;
 	u64 tmp;
 
-	if (sqe->ioprio || sqe->rw_flags || sqe->splice_fd_in)
+	if (sqe->rw_flags || sqe->splice_fd_in)
 		return -EINVAL;
 
 	tmp = READ_ONCE(sqe->fd);
@@ -4980,9 +4967,7 @@ 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))
+	if (sqe->buf_index || sqe->splice_fd_in)
 		return -EINVAL;
 
 	req->epoll.epfd = READ_ONCE(sqe->fd);
@@ -5026,9 +5011,7 @@ static int io_epoll_ctl(struct io_kiocb *req, unsigned int issue_flags)
 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))
+	if (sqe->buf_index || sqe->off || sqe->splice_fd_in)
 		return -EINVAL;
 
 	req->madvise.addr = READ_ONCE(sqe->addr);
@@ -5061,9 +5044,7 @@ static int io_madvise(struct io_kiocb *req, unsigned int issue_flags)
 
 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))
+	if (sqe->buf_index || sqe->addr || sqe->splice_fd_in)
 		return -EINVAL;
 
 	req->fadvise.offset = READ_ONCE(sqe->off);
@@ -5099,9 +5080,7 @@ static int io_statx_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 	const char __user *path;
 
-	if (unlikely(req->ctx->flags & IORING_SETUP_IOPOLL))
-		return -EINVAL;
-	if (sqe->ioprio || sqe->buf_index || sqe->splice_fd_in)
+	if (sqe->buf_index || sqe->splice_fd_in)
 		return -EINVAL;
 	if (req->flags & REQ_F_FIXED_FILE)
 		return -EBADF;
@@ -5146,10 +5125,7 @@ static int io_statx(struct io_kiocb *req, unsigned int issue_flags)
 
 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)
+	if (sqe->off || sqe->addr || sqe->len || sqe->rw_flags || sqe->buf_index)
 		return -EINVAL;
 	if (req->flags & REQ_F_FIXED_FILE)
 		return -EBADF;
@@ -5215,12 +5191,7 @@ static int io_close(struct io_kiocb *req, unsigned int issue_flags)
 
 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))
+	if (unlikely(sqe->addr || sqe->buf_index || sqe->splice_fd_in))
 		return -EINVAL;
 
 	req->sync.off = READ_ONCE(sqe->off);
@@ -5298,9 +5269,6 @@ 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;
@@ -5531,9 +5499,6 @@ 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);
@@ -5688,9 +5653,7 @@ 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)
+	if (sqe->len || sqe->buf_index)
 		return -EINVAL;
 
 	accept->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
@@ -5756,10 +5719,7 @@ 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)
+	if (sqe->len || sqe->buf_index || sqe->rw_flags || sqe->splice_fd_in)
 		return -EINVAL;
 
 	conn->addr = u64_to_user_ptr(READ_ONCE(sqe->addr));
@@ -6442,9 +6402,7 @@ static int io_poll_update_prep(struct io_kiocb *req,
 	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)
+	if (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 |
@@ -6474,9 +6432,7 @@ 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)
+	if (sqe->buf_index || sqe->off || sqe->addr)
 		return -EINVAL;
 	flags = READ_ONCE(sqe->len);
 	if (flags & ~IORING_POLL_ADD_MULTI)
@@ -6683,11 +6639,9 @@ static int io_timeout_remove_prep(struct io_kiocb *req,
 {
 	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)
+	if (sqe->buf_index || sqe->len || sqe->splice_fd_in)
 		return -EINVAL;
 
 	tr->ltimeout = false;
@@ -6757,10 +6711,7 @@ static int io_timeout_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe,
 	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)
+	if (sqe->buf_index || sqe->len != 1 || sqe->splice_fd_in)
 		return -EINVAL;
 	if (off && is_timeout_link)
 		return -EINVAL;
@@ -6942,11 +6893,9 @@ static int io_try_cancel(struct io_kiocb *req, struct io_cancel_data *cd)
 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_BUFFER_SELECT))
 		return -EINVAL;
-	if (sqe->ioprio || sqe->off || sqe->len || sqe->splice_fd_in)
+	if (sqe->off || sqe->len || sqe->splice_fd_in)
 		return -EINVAL;
 
 	req->cancel.addr = READ_ONCE(sqe->addr);
@@ -7032,7 +6981,7 @@ static int io_rsrc_update_prep(struct io_kiocb *req,
 {
 	if (unlikely(req->flags & (REQ_F_FIXED_FILE | REQ_F_BUFFER_SELECT)))
 		return -EINVAL;
-	if (sqe->ioprio || sqe->rw_flags || sqe->splice_fd_in)
+	if (sqe->rw_flags || sqe->splice_fd_in)
 		return -EINVAL;
 
 	req->rsrc_update.offset = READ_ONCE(sqe->off);
@@ -7845,6 +7794,11 @@ static int io_init_req(struct io_ring_ctx *ctx, struct io_kiocb *req,
 		}
 	}
 
+	if (!io_op_defs[opcode].ioprio && sqe->ioprio)
+		return -EINVAL;
+	if (!io_op_defs[opcode].iopoll && (ctx->flags & IORING_SETUP_IOPOLL))
+		return -EINVAL;
+
 	if (io_op_defs[opcode].needs_file) {
 		struct io_submit_state *state = &ctx->submit_state;
 
-- 
2.35.1



  reply	other threads:[~2022-04-26 18:33 UTC|newest]

Thread overview: 5+ messages / expand[flat|nested]  mbox.gz  Atom feed  top
2022-04-26 18:33 [PATCHSET RFC 0/4] Add support for IOSQE2_POLL_FIRST Jens Axboe
2022-04-26 18:33 ` Jens Axboe [this message]
2022-04-26 18:33 ` [PATCH 2/4] io_uring: add flags2 variable Jens Axboe
2022-04-26 18:33 ` [PATCH 3/4] io_uring: add IOSQE2_POLL_FIRST flag Jens Axboe
2022-04-26 18:33 ` [PATCH 4/4] io_uring: wire up IOSQE2_POLL_FIRST for send/sendmsg and recv/recvmsg Jens Axboe

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