From: Joe Thornber <ejt@xxxxxxxxxx>
This patch has been added to the 3.12 stable tree. If you have any
objections, please let us know.
===============
commit 6096d91af0b65a3967139b32d5adbb3647858a26 upstream.
The metadata space map has a simplified 'bootstrap' mode that is
operational when extending the space maps. Whilst in this mode it's
possible for some refcount decrement operations to become queued (eg, as
a result of shadowing one of the bitmap indexes). These decrements were
not being applied when switching out of bootstrap mode.
The effect of this bug was the leaking of a 4k metadata block. This is
detected by the latest version of thin_check as a non fatal error.
Signed-off-by: Joe Thornber <ejt@xxxxxxxxxx>
Signed-off-by: Mike Snitzer <snitzer@xxxxxxxxxx>
Signed-off-by: Jiri Slaby <jslaby@xxxxxxx>
---
drivers/md/persistent-data/dm-space-map-metadata.c | 50 +++++++++++++++-------
1 file changed, 35 insertions(+), 15 deletions(-)
diff --git a/drivers/md/persistent-data/dm-space-map-metadata.c b/drivers/md/persistent-data/dm-space-map-metadata.c
index d9a5aa532017..f6dea401232c 100644
--- a/drivers/md/persistent-data/dm-space-map-metadata.c
+++ b/drivers/md/persistent-data/dm-space-map-metadata.c
@@ -204,6 +204,27 @@ static void in(struct sm_metadata *smm)
smm->recursion_count++;
}
+static int apply_bops(struct sm_metadata *smm)
+{
+ int r = 0;
+
+ while (!brb_empty(&smm->uncommitted)) {
+ struct block_op bop;
+
+ r = brb_pop(&smm->uncommitted, &bop);
+ if (r) {
+ DMERR("bug in bop ring buffer");
+ break;
+ }
+
+ r = commit_bop(smm, &bop);
+ if (r)
+ break;
+ }
+
+ return r;
+}
+
static int out(struct sm_metadata *smm)
{
int r = 0;
@@ -216,21 +237,8 @@ static int out(struct sm_metadata *smm)
return -ENOMEM;
}
- if (smm->recursion_count == 1) {
- while (!brb_empty(&smm->uncommitted)) {
- struct block_op bop;
-
- r = brb_pop(&smm->uncommitted, &bop);
- if (r) {
- DMERR("bug in bop ring buffer");
- break;
- }
-
- r = commit_bop(smm, &bop);
- if (r)
- break;
- }
- }
+ if (smm->recursion_count == 1)
+ apply_bops(smm);
smm->recursion_count--;
@@ -702,6 +710,12 @@ static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
}
old_len = smm->begin;
+ r = apply_bops(smm);
+ if (r) {
+ DMERR("%s: apply_bops failed", __func__);
+ goto out;
+ }
+
r = sm_ll_commit(&smm->ll);
if (r)
goto out;
@@ -769,6 +783,12 @@ int dm_sm_metadata_create(struct dm_space_map *sm,
if (r)
return r;
+ r = apply_bops(smm);
+ if (r) {
+ DMERR("%s: apply_bops failed", __func__);
+ return r;
+ }
+
return sm_metadata_commit(sm);
}
--
2.5.0
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