linux-kernel - [PATCH 07/17] ublk: pass ublk_device to ublk_register_io

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [<thread-prev] [thread-next>] [day] [month] [year] [list]

Message-ID: <20250918014953.297897-8-csander@purestorage.com>
Date: Wed, 17 Sep 2025 19:49:43 -0600
From: Caleb Sander Mateos <csander@...estorage.com>
To: Ming Lei <ming.lei@...hat.com>,
	Jens Axboe <axboe@...nel.dk>
Cc: linux-block@...r.kernel.org,
	linux-kernel@...r.kernel.org,
	Caleb Sander Mateos <csander@...estorage.com>
Subject: [PATCH 07/17] ublk: pass ublk_device to ublk_register_io_buf()

Avoid repeating the 2 dereferences to get the ublk_device from the
io_uring_cmd by passing it from ublk_ch_uring_cmd_local() to
ublk_register_io_buf().

Signed-off-by: Caleb Sander Mateos <csander@...estorage.com>
---
 drivers/block/ublk_drv.c | 10 ++++++----
 1 file changed, 6 insertions(+), 4 deletions(-)

diff --git a/drivers/block/ublk_drv.c b/drivers/block/ublk_drv.c
index d6d8dcb72e4b..cb51f3f3cd33 100644
--- a/drivers/block/ublk_drv.c
+++ b/drivers/block/ublk_drv.c
@@ -2123,15 +2123,15 @@ static void ublk_io_release(void *priv)
 	else
 		ublk_put_req_ref(io, rq);
 }
 
 static int ublk_register_io_buf(struct io_uring_cmd *cmd,
+				struct ublk_device *ub,
 				const struct ublk_queue *ubq,
 				struct ublk_io *io,
 				unsigned int index, unsigned int issue_flags)
 {
-	struct ublk_device *ub = cmd->file->private_data;
 	struct request *req;
 	int ret;
 
 	if (!ublk_support_zero_copy(ubq))
 		return -EINVAL;
@@ -2150,10 +2150,11 @@ static int ublk_register_io_buf(struct io_uring_cmd *cmd,
 	return 0;
 }
 
 static int
 ublk_daemon_register_io_buf(struct io_uring_cmd *cmd,
+			    struct ublk_device *ub,
 			    const struct ublk_queue *ubq, struct ublk_io *io,
 			    unsigned index, unsigned issue_flags)
 {
 	unsigned new_registered_buffers;
 	struct request *req = io->req;
@@ -2163,11 +2164,12 @@ ublk_daemon_register_io_buf(struct io_uring_cmd *cmd,
 	 * Ensure there are still references for ublk_sub_req_ref() to release.
 	 * If not, fall back on the thread-safe buffer registration.
 	 */
 	new_registered_buffers = io->task_registered_buffers + 1;
 	if (unlikely(new_registered_buffers >= UBLK_REFCOUNT_INIT))
-		return ublk_register_io_buf(cmd, ubq, io, index, issue_flags);
+		return ublk_register_io_buf(cmd, ub, ubq, io, index,
+					    issue_flags);
 
 	if (!ublk_support_zero_copy(ubq) || !ublk_rq_has_data(req))
 		return -EINVAL;
 
 	ret = io_buffer_register_bvec(cmd, req, ublk_io_release, index,
@@ -2354,11 +2356,11 @@ static int ublk_ch_uring_cmd_local(struct io_uring_cmd *cmd,
 		/*
 		 * ublk_register_io_buf() accesses only the io's refcount,
 		 * so can be handled on any task
 		 */
 		if (_IOC_NR(cmd_op) == UBLK_IO_REGISTER_IO_BUF)
-			return ublk_register_io_buf(cmd, ubq, io, addr,
+			return ublk_register_io_buf(cmd, ub, ubq, io, addr,
 						    issue_flags);
 
 		goto out;
 	}
 
@@ -2376,11 +2378,11 @@ static int ublk_ch_uring_cmd_local(struct io_uring_cmd *cmd,
 			^ (_IOC_NR(cmd_op) == UBLK_IO_NEED_GET_DATA))
 		goto out;
 
 	switch (_IOC_NR(cmd_op)) {
 	case UBLK_IO_REGISTER_IO_BUF:
-		return ublk_daemon_register_io_buf(cmd, ubq, io, addr,
+		return ublk_daemon_register_io_buf(cmd, ub, ubq, io, addr,
 						   issue_flags);
 	case UBLK_IO_COMMIT_AND_FETCH_REQ:
 		ret = ublk_check_commit_and_fetch(ubq, io, addr);
 		if (ret)
 			goto out;
-- 
2.45.2