1 files changed, 29 insertions, 19 deletions

diff --git a/fs/btrfs/backref.c b/fs/btrfs/backref.c
index eaf133384a8f..8bc5e8ccb091 100644
--- a/fs/btrfs/backref.c
+++ b/fs/btrfs/backref.c
@@ -36,16 +36,23 @@ static int check_extent_in_eb(struct btrfs_key *key, struct extent_buffer *eb,
                                 u64 extent_item_pos,
                                 struct extent_inode_elem **eie)
 {
-        u64 data_offset;
-        u64 data_len;
+        u64 offset = 0;
         struct extent_inode_elem *e;
 
-        data_offset = btrfs_file_extent_offset(eb, fi);
-        data_len = btrfs_file_extent_num_bytes(eb, fi);
+        if (!btrfs_file_extent_compression(eb, fi) &&
+            !btrfs_file_extent_encryption(eb, fi) &&
+            !btrfs_file_extent_other_encoding(eb, fi)) {
+                u64 data_offset;
+                u64 data_len;
 
-        if (extent_item_pos < data_offset ||
-            extent_item_pos >= data_offset + data_len)
-                return 1;
+                data_offset = btrfs_file_extent_offset(eb, fi);
+                data_len = btrfs_file_extent_num_bytes(eb, fi);
+
+                if (extent_item_pos < data_offset ||
+                    extent_item_pos >= data_offset + data_len)
+                        return 1;
+                offset = extent_item_pos - data_offset;
+        }
 
         e = kmalloc(sizeof(*e), GFP_NOFS);
         if (!e)
@@ -53,7 +60,7 @@ static int check_extent_in_eb(struct btrfs_key *key, struct extent_buffer *eb,
 
         e->next = *eie;
         e->inum = key->objectid;
-        e->offset = key->offset + (extent_item_pos - data_offset);
+        e->offset = key->offset + offset;
         *eie = e;
 
         return 0;
@@ -189,7 +196,7 @@ static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
         struct extent_buffer *eb;
         struct btrfs_key key;
         struct btrfs_file_extent_item *fi;
-        struct extent_inode_elem *eie = NULL;
+        struct extent_inode_elem *eie = NULL, *old = NULL;
         u64 disk_byte;
 
         if (level != 0) {
@@ -223,6 +230,7 @@ static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
 
                 if (disk_byte == wanted_disk_byte) {
                         eie = NULL;
+                        old = NULL;
                         if (extent_item_pos) {
                                 ret = check_extent_in_eb(&key, eb, fi,
                                                 *extent_item_pos,
@@ -230,18 +238,20 @@ static int add_all_parents(struct btrfs_root *root, struct btrfs_path *path,
                                 if (ret < 0)
                                         break;
                         }
-                        if (!ret) {
-                                ret = ulist_add(parents, eb->start,
-                                                (uintptr_t)eie, GFP_NOFS);
-                                if (ret < 0)
-                                        break;
-                                if (!extent_item_pos) {
-                                        ret = btrfs_next_old_leaf(root, path,
-                                                        time_seq);
-                                        continue;
-                                }
+                        if (ret > 0)
+                                goto next;
+                        ret = ulist_add_merge(parents, eb->start,
+                                              (uintptr_t)eie,
+                                              (u64 *)&old, GFP_NOFS);
+                        if (ret < 0)
+                                break;
+                        if (!ret && extent_item_pos) {
+                                while (old->next)
+                                        old = old->next;
+                                old->next = eie;
                         }
                 }
+next:
                 ret = btrfs_next_old_item(root, path, time_seq);
         }