aboutsummaryrefslogtreecommitdiff
path: root/block/blk-settings.c
diff options
context:
space:
mode:
authorShaohua Li <shli@kernel.org>2012-12-14 11:15:36 +0800
committerJens Axboe <axboe@kernel.dk>2012-12-14 20:46:04 +0100
commit8dd2cb7e880d2f77fba53b523c99133ad5054cfd (patch)
treeea51e89f8c8bf9ca8e888d68ecf6732a52e8e99d /block/blk-settings.c
parent75274551c81796b636c5acb0c2597dec7ec2e6c4 (diff)
downloadlinux-linaro-stable-8dd2cb7e880d2f77fba53b523c99133ad5054cfd.tar.gz
block: discard granularity might not be power of 2
In MD raid case, discard granularity might not be power of 2, for example, a 4-disk raid5 has 3*chunk_size discard granularity. Correct the calculation for such cases. Reported-by: Neil Brown <neilb@suse.de> Signed-off-by: Shaohua Li <shli@fusionio.com> Signed-off-by: Jens Axboe <axboe@kernel.dk>
Diffstat (limited to 'block/blk-settings.c')
-rw-r--r--block/blk-settings.c6
1 files changed, 3 insertions, 3 deletions
diff --git a/block/blk-settings.c b/block/blk-settings.c
index 779bb7646bcd..c50ecf0ea3b1 100644
--- a/block/blk-settings.c
+++ b/block/blk-settings.c
@@ -611,7 +611,7 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
bottom = b->discard_granularity + alignment;
/* Verify that top and bottom intervals line up */
- if (max(top, bottom) & (min(top, bottom) - 1))
+ if ((max(top, bottom) % min(top, bottom)) != 0)
t->discard_misaligned = 1;
}
@@ -619,8 +619,8 @@ int blk_stack_limits(struct queue_limits *t, struct queue_limits *b,
b->max_discard_sectors);
t->discard_granularity = max(t->discard_granularity,
b->discard_granularity);
- t->discard_alignment = lcm(t->discard_alignment, alignment) &
- (t->discard_granularity - 1);
+ t->discard_alignment = lcm(t->discard_alignment, alignment) %
+ t->discard_granularity;
}
return ret;