Btrfs: make sure the backref walker catches all refs to our extent

Because we don't mess with the offset into the extent for compressed we will properly find both extents for this case [extent a][extent b][rest of extent a] but because we already added a ref for the front half we won't add the inode information for the second half. This causes us to leak that memory and not print out the other offset when we do logical-resolve. So fix this by calling ulist_add_merge and then add our eie to the existing entry if there is one. With this patch we get both offsets out of logical-resolve. With this and the other 2 patches I've sent we now pass btrfs/276 on my vm with compress-force=lzo set. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>

Btrfs: make sure the backref walker catches all refs to our extent
Because we don't mess with the offset into the extent for compressed we will properly find both extents for this case [extent a][extent b][rest of extent a] but because we already added a ref for the front half we won't add the inode information for the second half. This causes us to leak that memory and not print out the other offset when we do logical-resolve. So fix this by calling ulist_add_merge and then add our eie to the existing entry if there is one. With this patch we get both offsets out of logical-resolve. With this and the other 2 patches I've sent we now pass btrfs/276 on my vm with compress-force=lzo set. Thanks, Signed-off-by: Josef Bacik <jbacik@fusionio.com> Signed-off-by: Chris Mason <chris.mason@fusionio.com>
Josef Bacik · Chris Mason
1 parent 8ca15e05e6
Showing 1 changed file with 14 additions and 11 deletions Side-by-side Diff
fs/btrfs/backref.c
@@ -196,7 +196,7 @@
 	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) {
@@ -230,6 +230,7 @@
  
 		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,
  
@@ -237,18 +238,20 @@
 				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);
 	}
...	...	@@ -196,7 +196,7 @@
196	196	struct extent_buffer *eb;
197	197	struct btrfs_key key;
198	198	struct btrfs_file_extent_item *fi;
199		- struct extent_inode_elem *eie = NULL;
	199	+ struct extent_inode_elem eie = NULL, old = NULL;
200	200	u64 disk_byte;
201	201
202	202	if (level != 0) {
...	...	@@ -230,6 +230,7 @@
230	230
231	231	if (disk_byte == wanted_disk_byte) {
232	232	eie = NULL;
	233	+ old = NULL;
233	234	if (extent_item_pos) {
234	235	ret = check_extent_in_eb(&key, eb, fi,
235	236	*extent_item_pos,
236	237
...	...	@@ -237,18 +238,20 @@
237	238	if (ret < 0)
238	239	break;
239	240	}
240		- if (!ret) {
241		- ret = ulist_add(parents, eb->start,
242		- (uintptr_t)eie, GFP_NOFS);
243		- if (ret < 0)
244		- break;
245		- if (!extent_item_pos) {
246		- ret = btrfs_next_old_leaf(root, path,
247		- time_seq);
248		- continue;
249		- }
	241	+ if (ret > 0)
	242	+ goto next;
	243	+ ret = ulist_add_merge(parents, eb->start,
	244	+ (uintptr_t)eie,
	245	+ (u64 *)&old, GFP_NOFS);
	246	+ if (ret < 0)
	247	+ break;
	248	+ if (!ret && extent_item_pos) {
	249	+ while (old->next)
	250	+ old = old->next;
	251	+ old->next = eie;
250	252	}
251	253	}
	254	+next:
252	255	ret = btrfs_next_old_item(root, path, time_seq);
253	256	}
254	257