1 files changed, 29 insertions, 5 deletions

diff --git a/drivers/md/dm-thin-metadata.c b/drivers/md/dm-thin-metadata.c
index 1fa45695b68a..c219a053c7f6 100644
--- a/drivers/md/dm-thin-metadata.c
+++ b/drivers/md/dm-thin-metadata.c
@@ -1207,6 +1207,12 @@ static int __reserve_metadata_snap(struct dm_pool_metadata *pmd)
         dm_block_t held_root;
 
         /*
+         * We commit to ensure the btree roots which we increment in a
+         * moment are up to date.
+         */
+        __commit_transaction(pmd);
+
+        /*
          * Copy the superblock.
          */
         dm_sm_inc_block(pmd->metadata_sm, THIN_SUPERBLOCK_LOCATION);
@@ -1538,7 +1544,7 @@ static int __remove(struct dm_thin_device *td, dm_block_t block)
 static int __remove_range(struct dm_thin_device *td, dm_block_t begin, dm_block_t end)
 {
         int r;
-        unsigned count;
+        unsigned count, total_count = 0;
         struct dm_pool_metadata *pmd = td->pmd;
         dm_block_t keys[1] = { td->id };
         __le64 value;
@@ -1561,11 +1567,29 @@ static int __remove_range(struct dm_thin_device *td, dm_block_t begin, dm_block_
         if (r)
                 return r;
 
-        r = dm_btree_remove_leaves(&pmd->bl_info, mapping_root, &begin, end, &mapping_root, &count);
-        if (r)
-                return r;
+        /*
+         * Remove leaves stops at the first unmapped entry, so we have to
+         * loop round finding mapped ranges.
+         */
+        while (begin < end) {
+                r = dm_btree_lookup_next(&pmd->bl_info, mapping_root, &begin, &begin, &value);
+                if (r == -ENODATA)
+                        break;
+
+                if (r)
+                        return r;
+
+                if (begin >= end)
+                        break;
+
+                r = dm_btree_remove_leaves(&pmd->bl_info, mapping_root, &begin, end, &mapping_root, &count);
+                if (r)
+                        return r;
+
+                total_count += count;
+        }
 
-        td->mapped_blocks -= count;
+        td->mapped_blocks -= total_count;
         td->changed = 1;
 
         /*