4.9-stable review patch. If anyone has any objections, please let me know.
------------------
From: Joe Thornber <e...@redhat.com>
commit 0377a07c7a035e0d033cd8b29f0cb15244c0916a upstream.
When decrementing the reference count for a block, the free count wasn't
being updated if the reference count went to zero.
Signed-off-by: Joe Thornber <e...@redhat.com>
Signed-off-by: Mike Snitzer <snit...@redhat.com>
Signed-off-by: Greg Kroah-Hartman <gre...@linuxfoundation.org>
---
drivers/md/persistent-data/dm-space-map-disk.c | 15 ++++++++++++++-
1 file changed, 14 insertions(+), 1 deletion(-)
--- a/drivers/md/persistent-data/dm-space-map-disk.c
+++ b/drivers/md/persistent-data/dm-space-map-disk.c
@@ -142,10 +142,23 @@ static int sm_disk_inc_block(struct dm_s
static int sm_disk_dec_block(struct dm_space_map *sm, dm_block_t b)
{
+ int r;
+ uint32_t old_count;
enum allocation_event ev;
struct sm_disk *smd = container_of(sm, struct sm_disk, sm);
- return sm_ll_dec(&smd->ll, b, &ev);
+ r = sm_ll_dec(&smd->ll, b, &ev);
+ if (!r && (ev == SM_FREE)) {
+ /*
+ * It's only free if it's also free in the last
+ * transaction.
+ */
+ r = sm_ll_lookup(&smd->old_ll, b, &old_count);
+ if (!r && !old_count)
+ smd->nr_allocated_this_transaction--;
+ }
+
+ return r;
}
static int sm_disk_new_block(struct dm_space_map *sm, dm_block_t *b)
