Message ID | 20240202073104.2418230-2-dlemoal@kernel.org |
---|---|
State | Superseded |
Headers | show |
Series | Zone write plugging | expand |
On 2/2/24 15:30, Damien Le Moal wrote: > On completion of a flush sequence, blk_flush_restore_request() restores > the bio of a request to the original submitted BIO. However, the last > use of the request in the flush sequence may have been for a POSTFLUSH > which does not have a sector. So make sure to restore the request sector > using the iter sector of the original BIO. This BIO has not changed yet > since the completions of the flush sequence intermediate steps use > requeueing of the request until all steps are completed. > > Restoring the request sector ensures that blk_mq_end_request() will see > a valid sector as originally set when the flush BIO was submitted. > > Signed-off-by: Damien Le Moal <dlemoal@kernel.org> > --- > block/blk-flush.c | 1 + > 1 file changed, 1 insertion(+) > Reviewed-by: Hannes Reinecke <hare@suse.de> Cheers, Hannes
On 2/1/24 23:30, Damien Le Moal wrote: > diff --git a/block/blk-flush.c b/block/blk-flush.c > index b0f314f4bc14..2f58ae018464 100644 > --- a/block/blk-flush.c > +++ b/block/blk-flush.c > @@ -130,6 +130,7 @@ static void blk_flush_restore_request(struct request *rq) > * original @rq->bio. Restore it. > */ > rq->bio = rq->biotail; > + rq->__sector = rq->bio->bi_iter.bi_sector; Hmm ... is it guaranteed that rq->bio != NULL in this context? Thanks, Bart.
On 2/6/24 02:22, Bart Van Assche wrote: > On 2/1/24 23:30, Damien Le Moal wrote: >> diff --git a/block/blk-flush.c b/block/blk-flush.c >> index b0f314f4bc14..2f58ae018464 100644 >> --- a/block/blk-flush.c >> +++ b/block/blk-flush.c >> @@ -130,6 +130,7 @@ static void blk_flush_restore_request(struct request *rq) >> * original @rq->bio. Restore it. >> */ >> rq->bio = rq->biotail; >> + rq->__sector = rq->bio->bi_iter.bi_sector; > > Hmm ... is it guaranteed that rq->bio != NULL in this context? Yes. > > Thanks, > > Bart. >
diff --git a/block/blk-flush.c b/block/blk-flush.c index b0f314f4bc14..2f58ae018464 100644 --- a/block/blk-flush.c +++ b/block/blk-flush.c @@ -130,6 +130,7 @@ static void blk_flush_restore_request(struct request *rq) * original @rq->bio. Restore it. */ rq->bio = rq->biotail; + rq->__sector = rq->bio->bi_iter.bi_sector; /* make @rq a normal request */ rq->rq_flags &= ~RQF_FLUSH_SEQ;
On completion of a flush sequence, blk_flush_restore_request() restores the bio of a request to the original submitted BIO. However, the last use of the request in the flush sequence may have been for a POSTFLUSH which does not have a sector. So make sure to restore the request sector using the iter sector of the original BIO. This BIO has not changed yet since the completions of the flush sequence intermediate steps use requeueing of the request until all steps are completed. Restoring the request sector ensures that blk_mq_end_request() will see a valid sector as originally set when the flush BIO was submitted. Signed-off-by: Damien Le Moal <dlemoal@kernel.org> --- block/blk-flush.c | 1 + 1 file changed, 1 insertion(+)