dm cache: the CLEAN_SHUTDOWN flag was not being set
If the CLEAN_SHUTDOWN flag is not set when a cache is loaded then all cache
blocks are marked as dirty and a full writeback occurs.
__commit_transaction() is responsible for setting/clearing
CLEAN_SHUTDOWN (based the flags_mutator that is passed in).
Fix this issue, of the cache's on-disk flags being wrong, by making sure
__commit_transaction() does not reset the flags after the mutator has
altered the flags in preparation for them being serialized to disk.
before:
sb_flags = mutator(le32_to_cpu(disk_super->flags));
disk_super->flags = cpu_to_le32(sb_flags);
disk_super->flags = cpu_to_le32(cmd->flags);
after:
disk_super->flags = cpu_to_le32(cmd->flags);
sb_flags = mutator(le32_to_cpu(disk_super->flags));
disk_super->flags = cpu_to_le32(sb_flags);
Reported-by: Bogdan Vasiliev <bogdan.vasiliev@gmail.com>
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>
Cc: stable@vger.kernel.org
diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c
index 20cc36b..0a17d1b 100644
--- a/drivers/md/dm-cache-metadata.c
+++ b/drivers/md/dm-cache-metadata.c
@@ -634,10 +634,10 @@
disk_super = dm_block_data(sblock);
+ disk_super->flags = cpu_to_le32(cmd->flags);
if (mutator)
update_flags(disk_super, mutator);
- disk_super->flags = cpu_to_le32(cmd->flags);
disk_super->mapping_root = cpu_to_le64(cmd->root);
disk_super->hint_root = cpu_to_le64(cmd->hint_root);
disk_super->discard_root = cpu_to_le64(cmd->discard_root);