@@ -136,7 +136,7 @@ static int brb_push(struct bop_ring_buffer *brb,
return 0;
}
-static int brb_pop(struct bop_ring_buffer *brb, struct block_op *result)
+static int brb_peek(struct bop_ring_buffer *brb, struct block_op *result)
{
struct block_op *bop;
@@ -147,6 +147,17 @@ static int brb_pop(struct bop_ring_buffer *brb, struct block_op *result)
result->type = bop->type;
result->block = bop->block;
+ return 0;
+}
+
+static int brb_pop(struct bop_ring_buffer *brb)
+{
+ struct block_op *bop;
+
+ if (brb_empty(brb))
+ return -ENODATA;
+
+ bop = brb->bops + brb->begin;
brb->begin = brb_next(brb, brb->begin);
return 0;
@@ -211,7 +222,7 @@ static int apply_bops(struct sm_metadata *smm)
while (!brb_empty(&smm->uncommitted)) {
struct block_op bop;
- r = brb_pop(&smm->uncommitted, &bop);
+ r = brb_peek(&smm->uncommitted, &bop);
if (r) {
DMERR("bug in bop ring buffer");
break;
@@ -220,6 +231,8 @@ static int apply_bops(struct sm_metadata *smm)
r = commit_bop(smm, &bop);
if (r)
break;
+
+ brb_pop(&smm->uncommitted);
}
return r;
@@ -683,7 +696,6 @@ static struct dm_space_map bootstrap_ops = {
static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
{
int r, i;
- enum allocation_event ev;
struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm);
dm_block_t old_len = smm->ll.nr_blocks;
@@ -705,11 +717,12 @@ static int sm_metadata_extend(struct dm_space_map *sm, dm_block_t extra_blocks)
* allocate any new blocks.
*/
do {
- for (i = old_len; !r && i < smm->begin; i++) {
- r = sm_ll_inc(&smm->ll, i, &ev);
- if (r)
- goto out;
- }
+ for (i = old_len; !r && i < smm->begin; i++)
+ r = add_bop(smm, BOP_INC, i);
+
+ if (r)
+ goto out;
+
old_len = smm->begin;
r = apply_bops(smm);
@@ -754,7 +767,6 @@ int dm_sm_metadata_create(struct dm_space_map *sm,
{
int r;
dm_block_t i;
- enum allocation_event ev;
struct sm_metadata *smm = container_of(sm, struct sm_metadata, sm);
smm->begin = superblock + 1;
@@ -782,7 +794,7 @@ int dm_sm_metadata_create(struct dm_space_map *sm,
* allocated blocks that they were built from.
*/
for (i = superblock; !r && i < smm->begin; i++)
- r = sm_ll_inc(&smm->ll, i, &ev);
+ r = add_bop(smm, BOP_INC, i);
if (r)
return r;
This is a note to let you know that I have just added a patch titled dm space map metadata: fix ref counting bug when bootstrapping a new space map to the linux-3.19.y-queue branch of the 3.19.y-ckt extended stable tree which can be found at: http://kernel.ubuntu.com/git/ubuntu/linux.git/log/?h=linux-3.19.y-queue This patch is scheduled to be released in version 3.19.8-ckt13. If you, or anyone else, feels it should not be added to this tree, please reply to this email. For more information about the 3.19.y-ckt tree, see https://wiki.ubuntu.com/Kernel/Dev/ExtendedStable Thanks. -Kamal ---8<------------------------------------------------------------ From 0b5f23b5ef8bb23a992462181ae371082f3f963b Mon Sep 17 00:00:00 2001 From: Joe Thornber <ejt@redhat.com> Date: Wed, 9 Dec 2015 16:38:12 +0000 Subject: dm space map metadata: fix ref counting bug when bootstrapping a new space map commit 50dd842ad83b43bed71790efb31cfb2f6c05c9c1 upstream. When applying block operations (BOPs) do not remove them from the uncommitted BOP ring-buffer until after they've been applied -- in case we recurse. Also, perform BOP_INC operation, in dm_sm_metadata_create() and sm_metadata_extend(), in terms of the uncommitted BOP ring-buffer rather than using direct calls to sm_ll_inc(). Signed-off-by: Joe Thornber <ejt@redhat.com> Signed-off-by: Mike Snitzer <snitzer@redhat.com> Signed-off-by: Kamal Mostafa <kamal@canonical.com> --- drivers/md/persistent-data/dm-space-map-metadata.c | 32 +++++++++++++++------- 1 file changed, 22 insertions(+), 10 deletions(-) -- 1.9.1