Patches for 6.1-stable

PATCH Jens Axboe 2 participants 3 messages Aug 23, 2023 – Aug 28, 2023

Subsystems (2)

Stable branch io_uring

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Jens Axboe

author maintainer

2023-08-23 00:07 UTC #0 lore raw

Hi,

Looks like we missed a few backports related to MSG_RING, most likely because they required a bit of hand massaging. Can you queue these up? Thanks!

Signature · 1 line

Jens Axboe

From c47db9ca937e232606060077bb09cff49e75dbb7 Mon Sep 17 00:00:00 2001
From: Jens Axboe <[email protected]>
Date: Tue, 22 Aug 2023 18:00:02 -0600
Subject: [PATCH 4/4] io_uring/msg_ring: fix missing lock on overflow for
IOPOLL

Commit e12d7a46f65ae4b7d58a5e0c1cbfa825cf8d830d upstream.

If the target ring is configured with IOPOLL, then we always need to hold the target ring uring_lock before posting CQEs. We could just grab it unconditionally, but since we don't expect many target rings to be of this type, make grabbing the uring_lock conditional on the ring type.

Link https://lore.kernel.org/io-uring/Y8krlYa52%[email protected]/ open here

Reported-by Xingyuan Mo <[email protected]>

Signed-off-by Jens Axboe <[email protected]>

---
 io_uring/msg_ring.c | 20 +++++++++++++++-----
 1 file changed, 15 insertions(+), 5 deletions(-)

io_uring/msg_ring.c +15 -5

index 825d8c579fd3..cd922d2bef5f 100644
@@ -57,20 +57,30 @@ void io_msg_ring_cleanup(struct io_kiocb *req)
 	msg->src_file = NULL;
 }
 
-static int io_msg_ring_data(struct io_kiocb *req)
+static int io_msg_ring_data(struct io_kiocb *req, unsigned int issue_flags)
 {
 	struct io_ring_ctx *target_ctx = req->file->private_data;
 	struct io_msg *msg = io_kiocb_to_cmd(req, struct io_msg);
+	int ret;
 
 	if (msg->src_fd || msg->dst_fd || msg->flags)
 		return -EINVAL;
 	if (target_ctx->flags & IORING_SETUP_R_DISABLED)
 		return -EBADFD;
 
-	if (io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0, true))
-		return 0;
+	ret = -EOVERFLOW;
+	if (target_ctx->flags & IORING_SETUP_IOPOLL) {
+		if (unlikely(io_double_lock_ctx(target_ctx, issue_flags)))
+			return -EAGAIN;
+		if (io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0, true))
+			ret = 0;
+		io_double_unlock_ctx(target_ctx);
+	} else {
+		if (io_post_aux_cqe(target_ctx, msg->user_data, msg->len, 0, true))
+			ret = 0;
+	}
 
-	return -EOVERFLOW;
+	return ret;
 }
 
 static struct file *io_msg_grab_file(struct io_kiocb *req, unsigned int issue_flags)

@@ -175,7 +185,7 @@ int io_msg_ring(struct io_kiocb *req, unsigned int issue_flags)
 
 	switch (msg->cmd) {
 	case IORING_MSG_DATA:
-		ret = io_msg_ring_data(req);
+		ret = io_msg_ring_data(req, issue_flags);
 		break;
 	case IORING_MSG_SEND_FD:
 		ret = io_msg_send_fd(req, issue_flags);

Signature · 1 line

2.40.1

From 5c3ffa8ec64e0726dcbfe37b5d126701301011ed Mon Sep 17 00:00:00 2001
From: Jens Axboe <[email protected]>
Date: Thu, 19 Jan 2023 09:01:27 -0700
Subject: [PATCH 3/4] io_uring/msg_ring: move double lock/unlock helpers higher
up

Commit 423d5081d0451faa59a707e57373801da5b40141 upstream.

In preparation for needing them somewhere else, move them and get rid of the unused 'issue_flags' for the unlock side.

No functional changes in this patch.

Signed-off-by Jens Axboe <[email protected]>

---
 io_uring/msg_ring.c | 47 ++++++++++++++++++++++-----------------------
 1 file changed, 23 insertions(+), 24 deletions(-)

io_uring/msg_ring.c +23 ~~-24~~

65 lines not on this page · raw message

Signature · 1 line

2.40.1

From ef7b782465bd6943fbcacb4af4fbe790137a5820 Mon Sep 17 00:00:00 2001
From: Pavel Begunkov <[email protected]>
Date: Wed, 7 Dec 2022 03:53:35 +0000
Subject: [PATCH 2/4] io_uring: extract a io_msg_install_complete helper

Commit 172113101641cf1f9628c528ec790cb809f2b704 upstream.

Extract a helper called io_msg_install_complete() from io_msg_send_fd(), will be used later.

Signed-off-by Pavel Begunkov <[email protected]>

Link https://lore.kernel.org/r/1500ca1054cc4286a3ee1c60aacead57fcdfa02a.1670384893.git.asml.silence@gmail.com open here

Signed-off-by Jens Axboe <[email protected]>

---
 io_uring/msg_ring.c | 38 +++++++++++++++++++++-----------------
 1 file changed, 21 insertions(+), 17 deletions(-)

io_uring/msg_ring.c +21 ~~-17~~

index ee8e7ac8c582..fd96a0cd85f0 100644
@@ -94,40 +94,25 @@ static struct file *io_msg_grab_file(struct io_kiocb *req, unsigned int issue_fl
 	return file;
 }
 
-static int io_msg_send_fd(struct io_kiocb *req, unsigned int issue_flags)
+static int io_msg_install_complete(struct io_kiocb *req, unsigned int issue_flags)
 {
 	struct io_ring_ctx *target_ctx = req->file->private_data;
 	struct io_msg *msg = io_kiocb_to_cmd(req, struct io_msg);
-	struct io_ring_ctx *ctx = req->ctx;
 	struct file *src_file = msg->src_file;
 	int ret;
 
-	if (msg->len)
-		return -EINVAL;
-	if (target_ctx == ctx)
-		return -EINVAL;
-	if (target_ctx->flags & IORING_SETUP_R_DISABLED)
-		return -EBADFD;
-	if (!src_file) {
-		src_file = io_msg_grab_file(req, issue_flags);
-		if (!src_file)
-			return -EBADF;
-		msg->src_file = src_file;
-		req->flags |= REQ_F_NEED_CLEANUP;
-	}
-
 	if (unlikely(io_double_lock_ctx(target_ctx, issue_flags)))
 		return -EAGAIN;
 
 	ret = __io_fixed_fd_install(target_ctx, src_file, msg->dst_fd);
 	if (ret < 0)
 		goto out_unlock;
+
 	msg->src_file = NULL;
 	req->flags &= ~REQ_F_NEED_CLEANUP;
 
 	if (msg->flags & IORING_MSG_RING_CQE_SKIP)
 		goto out_unlock;
-
 	/*
 	 * If this fails, the target still received the file descriptor but
 	 * wasn't notified of the fact. This means that if this request

@@ -141,6 +126,25 @@ static int io_msg_send_fd(struct io_kiocb *req, unsigned int issue_flags)
 	return ret;
 }
 
+static int io_msg_send_fd(struct io_kiocb *req, unsigned int issue_flags)
+{
+	struct io_ring_ctx *target_ctx = req->file->private_data;
+	struct io_msg *msg = io_kiocb_to_cmd(req, struct io_msg);
+	struct io_ring_ctx *ctx = req->ctx;
+	struct file *src_file = msg->src_file;
+
+	if (target_ctx == ctx)
+		return -EINVAL;
+	if (!src_file) {
+		src_file = io_msg_grab_file(req, issue_flags);
+		if (!src_file)
+			return -EBADF;
+		msg->src_file = src_file;
+		req->flags |= REQ_F_NEED_CLEANUP;
+	}
+	return io_msg_install_complete(req, issue_flags);
+}
+
 int io_msg_ring_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe)
 {
 	struct io_msg *msg = io_kiocb_to_cmd(req, struct io_msg);

Signature · 1 line

2.40.1

From f10ba483becae0b8c7de0e9fe3e0f6d07a405b7a Mon Sep 17 00:00:00 2001
From: Pavel Begunkov <[email protected]>
Date: Wed, 7 Dec 2022 03:53:34 +0000
Subject: [PATCH 1/4] io_uring: get rid of double locking

Commit 11373026f2960390d5e330df4e92735c4265c440 upstream.

We don't need to take both uring_locks at once, msg_ring can be split in two parts, first getting a file from the filetable of the first ring and then installing it into the second one.

Signed-off-by Pavel Begunkov <[email protected]>

Link https://lore.kernel.org/r/a80ecc2bc99c3b3f2cf20015d618b7c51419a797.1670384893.git.asml.silence@gmail.com open here

Signed-off-by Jens Axboe <[email protected]>

---
 io_uring/msg_ring.c | 85 ++++++++++++++++++++++++++-------------------
 io_uring/msg_ring.h |  1 +
 io_uring/opdef.c    |  1 +
 3 files changed, 51 insertions(+), 36 deletions(-)

io_uring/msg_ring.c +49 ~~-36~~

144 lines not on this page · raw message

io_uring/msg_ring.h +1 -0

index fb9601f202d0..3987ee6c0e5f 100644
@@ -2,3 +2,4 @@
 
 int io_msg_ring_prep(struct io_kiocb *req, const struct io_uring_sqe *sqe);
 int io_msg_ring(struct io_kiocb *req, unsigned int issue_flags);
+void io_msg_ring_cleanup(struct io_kiocb *req);

io_uring/opdef.c +1 -0

index 04dd2c983fce..3aa0d65c50e3 100644
@@ -445,6 +445,7 @@ const struct io_op_def io_op_defs[] = {
 		.name			= "MSG_RING",
 		.prep			= io_msg_ring_prep,
 		.issue			= io_msg_ring,
+		.cleanup		= io_msg_ring_cleanup,
 	},
 	[IORING_OP_FSETXATTR] = {
 		.needs_file = 1,

Signature · 1 line

2.40.1

Greg Kroah-Hartman

maintainer

2023-08-27 07:15 UTC #1 lore raw

Quoted 5 lines · Jens Axboe

Hi,
Looks like we missed a few backports related to MSG_RING, most likely because they required a bit of hand massaging. Can you queue these up? Thanks!

All now queued up, thanks.

greg k-h

Jens Axboe

author maintainer

2023-08-28 14:30 UTC #2 lore raw

Quoted 8 lines · Greg Kroah-Hartman

Quoted 5 lines · Jens Axboe
Hi,
Looks like we missed a few backports related to MSG_RING, most likely because they required a bit of hand massaging. Can you queue these up? Thanks!
All now queued up, thanks.

Thanks Greg!

Signature · 1 line

Jens Axboe