diff options
| author | Mike Snitzer <snitzer@redhat.com> | 2013-08-20 15:02:41 -0400 |
|---|---|---|
| committer | Mike Snitzer <snitzer@redhat.com> | 2013-08-23 09:02:14 -0400 |
| commit | f610937214e2ac8c4225df9a124ea0de1f030626 (patch) | |
| tree | 879998ed1f96546a6dd555debcd74ad09b88be29 | |
| parent | 0cc67cd9c55c4b1f076abca06c922751088e6d86 (diff) | |
| download | linux-f610937214e2ac8c4225df9a124ea0de1f030626.tar.bz2 | |
dm cache: 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 cache's data block size.
Without this patch mkfs.xfs does not recognize the cache 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>
| -rw-r--r-- | drivers/md/dm-cache-target.c | 12 |
1 files changed, 10 insertions, 2 deletions
diff --git a/drivers/md/dm-cache-target.c b/drivers/md/dm-cache-target.c index 31985ea81408..22ff650ac24e 100644 --- a/drivers/md/dm-cache-target.c +++ b/drivers/md/dm-cache-target.c @@ -2612,9 +2612,17 @@ static void set_discard_limits(struct cache *cache, struct queue_limits *limits) static void cache_io_hints(struct dm_target *ti, struct queue_limits *limits) { struct cache *cache = ti->private; + uint64_t io_opt_sectors = limits->io_opt >> SECTOR_SHIFT; - blk_limits_io_min(limits, 0); - blk_limits_io_opt(limits, cache->sectors_per_block << SECTOR_SHIFT); + /* + * If the system-determined stacked limits are compatible with the + * cache's blocksize (io_opt is a factor) do not override them. + */ + if (io_opt_sectors < cache->sectors_per_block || + do_div(io_opt_sectors, cache->sectors_per_block)) { + blk_limits_io_min(limits, 0); + blk_limits_io_opt(limits, cache->sectors_per_block << SECTOR_SHIFT); + } set_discard_limits(cache, limits); } |