On Tue, Jul 03, 2012 at 04:21:34PM +0200, Paolo Bonzini wrote: [..] > > That raises an interesting question for patch3. If the discard is happening to > > a partition, shouldn't you be looking at partition discard_alignment > > instead of always looking at queue discard_alignment? > > Good point! Like this? This looks better. > > diff --git a/include/linux/blkdev.h b/include/linux/blkdev.h > index ba43f40..3530764 100644 > --- a/include/linux/blkdev.h > +++ b/include/linux/blkdev.h > @@ -1125,6 +1125,16 @@ static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector > & (lim->discard_granularity - 1); > } > > +static inline int bdev_discard_alignment(struct block_device *bdev) > +{ > + struct request_queue *q = bdev_get_queue(bdev); > + > + if (bdev != bdev->bd_contains) > + return bdev->bd_part->discard_alignment; > + > + return q->limits.discard_alignment; > +} > + > static inline unsigned int queue_discard_zeroes_data(struct request_queue *q) > { > if (q->limits.max_discard_sectors && q->limits.discard_zeroes_data == 1) > diff --git a/block/blk-lib.c b/block/blk-lib.c > index b2bde5c..77d8869 100644 > --- a/block/blk-lib.c > +++ b/block/blk-lib.c > @@ -58,7 +58,7 @@ int blkdev_issue_discard(struct block_device *bdev, sector_t sector, > /* Zero-sector (unknown) and one-sector granularities are the same. */ > granularity = max(q->limits.discard_granularity >> 9, 1U); > mask = granularity - 1; > - alignment = (q->limits.discard_alignment >> 9) & mask; > + alignment = bdev_discard_alignment(bdev) >> 9; Why are you removing AND with mask operation? I don't see any AND operation being done in bdev_discard_alignment(). Thanks Vivek -- dm-devel mailing list dm-devel@xxxxxxxxxx https://www.redhat.com/mailman/listinfo/dm-devel