* [PATCH] block: Update blk_update_request() documentation
@ 2021-05-19 17:52 Bart Van Assche
2021-06-03 20:03 ` Bart Van Assche
2021-06-03 20:37 ` Jens Axboe
0 siblings, 2 replies; 3+ messages in thread
From: Bart Van Assche @ 2021-05-19 17:52 UTC (permalink / raw)
To: Jens Axboe
Cc: linux-block, Christoph Hellwig, Bart Van Assche, Ming Lei,
Hannes Reinecke
Although the original intent was to use blk_update_request() in stacking
block drivers only, it is used much more widely today. Reflect this in the
documentation block above this function. See also:
* commit 32fab448e5e8 ("block: add request update interface").
* commit 2e60e02297cf ("block: clean up request completion API").
* commit ed6565e73424 ("block: handle partial completions for special
payload requests").
Cc: Christoph Hellwig <hch@lst.de>
Cc: Ming Lei <ming.lei@redhat.com>
Cc: Hannes Reinecke <hare@suse.de>
Signed-off-by: Bart Van Assche <bvanassche@acm.org>
---
block/blk-core.c | 12 ++++--------
1 file changed, 4 insertions(+), 8 deletions(-)
diff --git a/block/blk-core.c b/block/blk-core.c
index 689aac2625d2..b65da5a33e20 100644
--- a/block/blk-core.c
+++ b/block/blk-core.c
@@ -1385,26 +1385,22 @@ void blk_steal_bios(struct bio_list *list, struct request *rq)
EXPORT_SYMBOL_GPL(blk_steal_bios);
/**
- * blk_update_request - Special helper function for request stacking drivers
+ * blk_update_request - Complete multiple bytes without completing the request
* @req: the request being processed
* @error: block status code
- * @nr_bytes: number of bytes to complete @req
+ * @nr_bytes: number of bytes to complete for @req
*
* Description:
* Ends I/O on a number of bytes attached to @req, but doesn't complete
* the request structure even if @req doesn't have leftover.
* If @req has leftover, sets it up for the next range of segments.
*
- * This special helper function is only for request stacking drivers
- * (e.g. request-based dm) so that they can handle partial completion.
- * Actual device drivers should use blk_mq_end_request instead.
- *
* Passing the result of blk_rq_bytes() as @nr_bytes guarantees
* %false return from this function.
*
* Note:
- * The RQF_SPECIAL_PAYLOAD flag is ignored on purpose in both
- * blk_rq_bytes() and in blk_update_request().
+ * The RQF_SPECIAL_PAYLOAD flag is ignored on purpose in this function
+ * except in the consistency check at the end of this function.
*
* Return:
* %false - this request doesn't have any more data
^ permalink raw reply related [flat|nested] 3+ messages in thread
* Re: [PATCH] block: Update blk_update_request() documentation
2021-05-19 17:52 [PATCH] block: Update blk_update_request() documentation Bart Van Assche
@ 2021-06-03 20:03 ` Bart Van Assche
2021-06-03 20:37 ` Jens Axboe
1 sibling, 0 replies; 3+ messages in thread
From: Bart Van Assche @ 2021-06-03 20:03 UTC (permalink / raw)
To: Jens Axboe; +Cc: linux-block, Christoph Hellwig, Ming Lei, Hannes Reinecke
On 5/19/21 10:52 AM, Bart Van Assche wrote:
> Although the original intent was to use blk_update_request() in stacking
> block drivers only, it is used much more widely today. Reflect this in the
> documentation block above this function. See also:
> * commit 32fab448e5e8 ("block: add request update interface").
> * commit 2e60e02297cf ("block: clean up request completion API").
> * commit ed6565e73424 ("block: handle partial completions for special
> payload requests").
Can anyone help with reviewing this patch?
Thanks,
Bart.
^ permalink raw reply [flat|nested] 3+ messages in thread
* Re: [PATCH] block: Update blk_update_request() documentation
2021-05-19 17:52 [PATCH] block: Update blk_update_request() documentation Bart Van Assche
2021-06-03 20:03 ` Bart Van Assche
@ 2021-06-03 20:37 ` Jens Axboe
1 sibling, 0 replies; 3+ messages in thread
From: Jens Axboe @ 2021-06-03 20:37 UTC (permalink / raw)
To: Bart Van Assche; +Cc: linux-block, Christoph Hellwig, Ming Lei, Hannes Reinecke
On 5/19/21 11:52 AM, Bart Van Assche wrote:
> Although the original intent was to use blk_update_request() in stacking
> block drivers only, it is used much more widely today. Reflect this in the
> documentation block above this function. See also:
> * commit 32fab448e5e8 ("block: add request update interface").
> * commit 2e60e02297cf ("block: clean up request completion API").
> * commit ed6565e73424 ("block: handle partial completions for special
> payload requests").
Applied, thanks Bart.
--
Jens Axboe
^ permalink raw reply [flat|nested] 3+ messages in thread
end of thread, other threads:[~2021-06-03 20:37 UTC | newest]
Thread overview: 3+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2021-05-19 17:52 [PATCH] block: Update blk_update_request() documentation Bart Van Assche
2021-06-03 20:03 ` Bart Van Assche
2021-06-03 20:37 ` Jens Axboe
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).