blk-mq: avoid a mess of casts for blk_end_sync_rq

Instead of trying to cast a __bitwise 32-bit integer to a larger integer
and then a pointer, just allow a struct with the blk_status_t and the
completion on stack and set the end_io_data to that.  Use the
opportunity to move the code to where it belongs and drop rather
confusing comments.

Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Chaitanya Kulkarni <kch@nvidia.com>
Link: https://lore.kernel.org/r/20220524121530.943123-3-hch@lst.de
Signed-off-by: Jens Axboe <axboe@kernel.dk>
This commit is contained in:
Christoph Hellwig 2022-05-24 14:15:29 +02:00 committed by Jens Axboe
parent ae948fd6d0
commit 32ac5a9b8b

View File

@ -1151,24 +1151,6 @@ void blk_mq_start_request(struct request *rq)
}
EXPORT_SYMBOL(blk_mq_start_request);
/**
* blk_end_sync_rq - executes a completion event on a request
* @rq: request to complete
* @error: end I/O status of the request
*/
static void blk_end_sync_rq(struct request *rq, blk_status_t error)
{
struct completion *waiting = rq->end_io_data;
rq->end_io_data = (void *)(uintptr_t)error;
/*
* complete last, if this is a stack request the process (and thus
* the rq pointer) could be invalid right after this complete()
*/
complete(waiting);
}
/*
* Allow 2x BLK_MAX_REQUEST_COUNT requests on plug queue for multiple
* queues. This is important for md arrays to benefit from merging
@ -1231,6 +1213,19 @@ void blk_execute_rq_nowait(struct request *rq, bool at_head, rq_end_io_fn *done)
}
EXPORT_SYMBOL_GPL(blk_execute_rq_nowait);
struct blk_rq_wait {
struct completion done;
blk_status_t ret;
};
static void blk_end_sync_rq(struct request *rq, blk_status_t ret)
{
struct blk_rq_wait *wait = rq->end_io_data;
wait->ret = ret;
complete(&wait->done);
}
static bool blk_rq_is_poll(struct request *rq)
{
if (!rq->mq_hctx)
@ -1262,7 +1257,9 @@ static void blk_rq_poll_completion(struct request *rq, struct completion *wait)
*/
blk_status_t blk_execute_rq(struct request *rq, bool at_head)
{
DECLARE_COMPLETION_ONSTACK(wait);
struct blk_rq_wait wait = {
.done = COMPLETION_INITIALIZER_ONSTACK(wait.done),
};
WARN_ON(irqs_disabled());
WARN_ON(!blk_rq_is_passthrough(rq));
@ -1274,7 +1271,7 @@ blk_status_t blk_execute_rq(struct request *rq, bool at_head)
blk_mq_sched_insert_request(rq, at_head, true, false);
if (blk_rq_is_poll(rq)) {
blk_rq_poll_completion(rq, &wait);
blk_rq_poll_completion(rq, &wait.done);
} else {
/*
* Prevent hang_check timer from firing at us during very long
@ -1283,14 +1280,14 @@ blk_status_t blk_execute_rq(struct request *rq, bool at_head)
unsigned long hang_check = sysctl_hung_task_timeout_secs;
if (hang_check)
while (!wait_for_completion_io_timeout(&wait,
while (!wait_for_completion_io_timeout(&wait.done,
hang_check * (HZ/2)))
;
else
wait_for_completion_io(&wait);
wait_for_completion_io(&wait.done);
}
return (blk_status_t)(uintptr_t)rq->end_io_data;
return wait.ret;
}
EXPORT_SYMBOL(blk_execute_rq);