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authorMike Snitzer <snitzer@redhat.com>2013-08-20 23:02:41 +0400
committerMike Snitzer <snitzer@redhat.com>2013-08-23 17:02:14 +0400
commit0cc67cd9c55c4b1f076abca06c922751088e6d86 (patch)
treececddf3bbb42ae79bc6262293446d7ad73ba1601 /drivers/md/dm-thin.c
parenta561ddbec156c73ecf2852d77574ddef52970dcf (diff)
downloadlinux-0cc67cd9c55c4b1f076abca06c922751088e6d86.tar.xz
dm thin: fix stacking of geometry limits
Do not blindly override the queue limits (specifically io_min and io_opt). Allow traditional stacking of these limits if io_opt is a factor of the thin-pool's data block size. Without this patch mkfs.xfs does not recognize the thin device's provided limits as a useful geometry (e.g. raid) so these hints are ignored. This was due to setting io_min to a useless value. Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Alasdair G Kergon <agk@redhat.com> Acked-by: Joe Thornber <ejt@redhat.com>
Diffstat (limited to 'drivers/md/dm-thin.c')
-rw-r--r--drivers/md/dm-thin.c12
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/md/dm-thin.c b/drivers/md/dm-thin.c
index 88f2f802d528..21328a371e58 100644
--- a/drivers/md/dm-thin.c
+++ b/drivers/md/dm-thin.c
@@ -2648,9 +2648,17 @@ static void pool_io_hints(struct dm_target *ti, struct queue_limits *limits)
{
struct pool_c *pt = ti->private;
struct pool *pool = pt->pool;
+ uint64_t io_opt_sectors = limits->io_opt >> SECTOR_SHIFT;
- blk_limits_io_min(limits, 0);
- blk_limits_io_opt(limits, pool->sectors_per_block << SECTOR_SHIFT);
+ /*
+ * If the system-determined stacked limits are compatible with the
+ * pool's blocksize (io_opt is a factor) do not override them.
+ */
+ if (io_opt_sectors < pool->sectors_per_block ||
+ do_div(io_opt_sectors, pool->sectors_per_block)) {
+ blk_limits_io_min(limits, 0);
+ blk_limits_io_opt(limits, pool->sectors_per_block << SECTOR_SHIFT);
+ }
/*
* pt->adjusted_pf is a staging area for the actual features to use.