[PATCHv2 3/5] block: return errors from blk_execute_rq()

Keith Busch
2021-04-23T22:07:26Z

The synchronous blk_execute_rq() had not provided a way for its callers
to know if its request was successful or not. Return the errno from the
dispatch status.

Signed-off-by: Keith Busch <kbusch@kernel.org>
---
block/blk-exec.c | 6 ++++--
include/linux/blkdev.h | 2 +-
2 files changed, 5 insertions(+), 3 deletions(-)

diff --git a/block/blk-exec.c b/block/blk-exec.c
index b960ad187ba5..4e8e6fe20956 100644
--- a/block/blk-exec.c
+++ b/block/blk-exec.c
@@ -21,7 +21,7 @@ static void blk_end_sync_rq(struct request *rq, blk_status_t error)
{
struct completion *waiting = rq->end_io_data;

- rq->end_io_data = NULL;
+ rq->end_io_data = ERR_PTR(blk_status_to_errno(error));

/*
* complete last, if this is a stack request the process (and thus
@@ -77,8 +77,9 @@ static bool blk_rq_is_poll(struct request *rq)
* Description:
* Insert a fully prepared request at the back of the I/O scheduler queue
* for execution and wait for completion.
+ * Return: The errno value of the blk_status_t provided to blk_mq_end_request().
*/
-void blk_execute_rq(struct gendisk *bd_disk, struct request *rq, int at_head)
+int blk_execute_rq(struct gendisk *bd_disk, struct request *rq, int at_head)
{
DECLARE_COMPLETION_ONSTACK(wait);
unsigned long hang_check;
@@ -97,5 +98,6 @@ void blk_execute_rq(struct gendisk *bd_disk, struct request *rq, int at_head)
while (!wait_for_completion_io_timeout(&wait, hang_check * (HZ/2)));
else
wait_for_completion_io(&wait);
+ return PTR_ERR_OR_ZERO(rq->end_io_data);
}
EXPORT_SYMBOL(blk_execute_rq);
diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h
index b91ba6207365..15e4ffac33af 100644
--- a/include/linux/blkdev.h
+++ b/include/linux/blkdev.h
@@ -938,7 +938,7 @@ extern int blk_rq_map_kern(struct request_queue *, struct request *, void *, uns
extern int blk_rq_map_user_iov(struct request_queue *, struct request *,
struct rq_map_data *, const struct iov_iter *,
gfp_t);
-extern void blk_execute_rq(struct gendisk *, struct request *, int);
+extern int blk_execute_rq(struct gendisk *, struct request *, int);
extern void blk_execute_rq_nowait(struct gendisk *,
struct request *, int, rq_end_io_fn *);

--
2.25.4