From 825d8bbd2f32cb229c3b6653bd454832c3c20acb Mon Sep 17 00:00:00 2001 From: Mike Snitzer Date: Mon, 20 May 2024 13:34:06 -0400 Subject: dm: always manage discard support in terms of max_hw_discard_sectors Commit 4f563a64732d ("block: add a max_user_discard_sectors queue limit") changed block core to set max_discard_sectors to: min(lim->max_hw_discard_sectors, lim->max_user_discard_sectors) Since commit 1c0e720228ad ("dm: use queue_limits_set") it was reported dm-thinp was failing in a few fstests (generic/347 and generic/405) with the first WARN_ON_ONCE in dm_cell_key_has_valid_range() being reported, e.g.: WARNING: CPU: 1 PID: 30 at drivers/md/dm-bio-prison-v1.c:128 dm_cell_key_has_valid_range+0x3d/0x50 blk_set_stacking_limits() sets max_user_discard_sectors to UINT_MAX, so given how block core now sets max_discard_sectors (detailed above) it follows that blk_stack_limits() stacks up the underlying device's max_hw_discard_sectors and max_discard_sectors is set to match it. If max_hw_discard_sectors exceeds dm's BIO_PRISON_MAX_RANGE, then dm_cell_key_has_valid_range() will trigger the warning with: WARN_ON_ONCE(key->block_end - key->block_begin > BIO_PRISON_MAX_RANGE) Aside from this warning, the discard will fail. Fix this and other DM issues by governing discard support in terms of max_hw_discard_sectors instead of max_discard_sectors. Reported-by: Theodore Ts'o Fixes: 1c0e720228ad ("dm: use queue_limits_set") Signed-off-by: Mike Snitzer --- drivers/md/dm-snap.c | 2 +- 1 file changed, 1 insertion(+), 1 deletion(-) (limited to 'drivers/md/dm-snap.c') diff --git a/drivers/md/dm-snap.c b/drivers/md/dm-snap.c index 0ace06d1bee3..f40c18da4000 100644 --- a/drivers/md/dm-snap.c +++ b/drivers/md/dm-snap.c @@ -2410,7 +2410,7 @@ static void snapshot_io_hints(struct dm_target *ti, struct queue_limits *limits) /* All discards are split on chunk_size boundary */ limits->discard_granularity = snap->store->chunk_size; - limits->max_discard_sectors = snap->store->chunk_size; + limits->max_hw_discard_sectors = snap->store->chunk_size; up_read(&_origins_lock); } -- cgit