dm cache metadata: fix metadata2 format's blocks_are_clean_separate_dirty

The dm_bitset_cursor_begin() call was using the incorrect nr_entries.
Also, the last dm_bitset_cursor_next() must be avoided if we're at the
end of the cursor.

Fixes: 7f1b21591a6 ("dm cache metadata: use cursor api in blocks_are_clean_separate_dirty()")
Signed-off-by: Joe Thornber <ejt@redhat.com>
Signed-off-by: Mike Snitzer <snitzer@redhat.com>

1 files changed, 5 insertions, 3 deletions

diff --git a/drivers/md/dm-cache-metadata.c b/drivers/md/dm-cache-metadata.c
index e4c2c1a1e993..6735c8d6a445 100644
--- a/drivers/md/dm-cache-metadata.c
+++ b/drivers/md/dm-cache-metadata.c
@@ -932,7 +932,7 @@ static int blocks_are_clean_separate_dirty(struct dm_cache_metadata *cmd,
         *result = true;
 
         r = dm_bitset_cursor_begin(&cmd->dirty_info, cmd->dirty_root,
-                                   from_cblock(begin), &cmd->dirty_cursor);
+                                   from_cblock(cmd->cache_blocks), &cmd->dirty_cursor);
         if (r) {
                 DMERR("%s: dm_bitset_cursor_begin for dirty failed", __func__);
                 return r;
@@ -959,14 +959,16 @@ static int blocks_are_clean_separate_dirty(struct dm_cache_metadata *cmd,
                         return 0;
                 }
 
+                begin = to_cblock(from_cblock(begin) + 1);
+                if (begin == end)
+                        break;
+
                 r = dm_bitset_cursor_next(&cmd->dirty_cursor);
                 if (r) {
                         DMERR("%s: dm_bitset_cursor_next for dirty failed", __func__);
                         dm_bitset_cursor_end(&cmd->dirty_cursor);
                         return r;
                 }
-
-                begin = to_cblock(from_cblock(begin) + 1);
         }
 
         dm_bitset_cursor_end(&cmd->dirty_cursor);