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 each target's block size.
Without this patch mkfs.xfs does not recognize these target 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@xxxxxxxxxx>
---
drivers/md/dm-cache-target.c | 12 ++++++++++--
drivers/md/dm-thin.c | 12 ++++++++++--
2 files changed, 20 insertions(+), 4 deletions(-)
Index: linux/drivers/md/dm-cache-target.c
===================================================================
--- linux.orig/drivers/md/dm-cache-target.c
+++ linux/drivers/md/dm-cache-target.c
@@ -2609,9 +2609,17 @@ static void set_discard_limits(struct ca
static void cache_io_hints(struct dm_target *ti, struct queue_limits *limits)
{
struct cache *cache = ti->private;
+ unsigned 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);
}
Index: linux/drivers/md/dm-thin.c
===================================================================
--- linux.orig/drivers/md/dm-thin.c
+++ linux/drivers/md/dm-thin.c
@@ -2648,9 +2648,17 @@ static void pool_io_hints(struct dm_targ
{
struct pool_c *pt = ti->private;
struct pool *pool = pt->pool;
+ unsigned 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.
--
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