From: Su Yue <suy.f...@cn.fujitsu.com>
Introduce delete_extent_tree_item() and repair_extent_item() to do
delete only.
while checking a extent tree, just delete wrong item.
For extent item, free wrong backref. Otherwise, do delete.
So the rest items in extent tree should be correct.
Signed-off-by: Su Yue <suy.f...@cn.fujitsu.com>
---
cmds-check.c | 151 ++++++++++++++++++++++++++++++++++++++++++++++++++++++-----
1 file changed, 138 insertions(+), 13 deletions(-)
diff --git a/cmds-check.c b/cmds-check.c
index 7c9036c..0f26394 100644
--- a/cmds-check.c
+++ b/cmds-check.c
@@ -11084,24 +11084,77 @@ out:
}
/*
+ * Only delete backref if REFERENCER_MISSING now
+ *
+ * Returns <0 the extent was deleted
+ * Returns >0 the backref was deleted but extent is still existed,
+ * returned value means err after repair
+ * Returns 0 nothing happened
+ */
+static int repair_extent_item(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root, struct btrfs_path *path,
+ u64 bytenr, u64 num_bytes, u64 parent, u64 root_objectid,
+ u64 owner, u64 offset, int err)
+{
+ struct btrfs_key old_key;
+ int freed = 0;
+ int ret;
+
+ btrfs_item_key_to_cpu(path->nodes[0], &old_key, path->slots[0]);
+
+ if (err & (REFERENCER_MISSING | REFERENCER_MISMATCH)) {
+ /* delete the backref */
+ ret = btrfs_free_extent(trans, root->fs_info->fs_root, bytenr,
+ num_bytes, parent, root_objectid, owner, offset);
+ if (!ret) {
+ freed = 1;
+ err &= ~REFERENCER_MISSING;
+ printf("Delete backref in extent [%llu %llu]\n",
+ bytenr, num_bytes);
+ } else {
+ error("fail to delete backref in extent [%llu %llu]\n",
+ bytenr, num_bytes);
+ }
+ }
+
+ /* btrfs_free_extent may delete the extent */
+ btrfs_release_path(path);
+ ret = btrfs_search_slot(NULL, root, &old_key, path, 0, 0);
+
+ if (ret)
+ ret = -ENOENT;
+ else if (freed)
+ ret = err;
+ return ret;
+}
+
+/*
* This function will check a given extent item, including its backref and
* itself (like crossing stripe boundary and type)
*
* Since we don't use extent_record anymore, introduce new error bit
*/
-static int check_extent_item(struct btrfs_fs_info *fs_info,
- struct extent_buffer *eb, int slot)
+static int check_extent_item(struct btrfs_trans_handle *trans,
+ struct btrfs_fs_info *fs_info,
+ struct btrfs_path *path)
{
struct btrfs_extent_item *ei;
struct btrfs_extent_inline_ref *iref;
struct btrfs_extent_data_ref *dref;
+ struct extent_buffer *eb = path->nodes[0];
unsigned long end;
unsigned long ptr;
+ int slot = path->slots[0];
int type;
u32 nodesize = btrfs_super_nodesize(fs_info->super_copy);
u32 item_size = btrfs_item_size_nr(eb, slot);
u64 flags;
u64 offset;
+ u64 parent;
+ u64 num_bytes;
+ u64 root_objectid;
+ u64 owner;
+ u64 owner_offset;
int metadata = 0;
int level;
struct btrfs_key key;
@@ -11109,10 +11162,13 @@ static int check_extent_item(struct btrfs_fs_info
*fs_info,
int err = 0;
btrfs_item_key_to_cpu(eb, &key, slot);
- if (key.type == BTRFS_EXTENT_ITEM_KEY)
+ if (key.type == BTRFS_EXTENT_ITEM_KEY) {
bytes_used += key.offset;
- else
+ num_bytes = key.offset;
+ } else {
bytes_used += nodesize;
+ num_bytes = nodesize;
+ }
if (item_size < sizeof(*ei)) {
/*
@@ -11150,7 +11206,6 @@ static int check_extent_item(struct btrfs_fs_info
*fs_info,
level = key.offset;
}
end = (unsigned long)ei + item_size;
-
next:
/* Reached extent item end normally */
if (ptr == end)
@@ -11164,42 +11219,63 @@ next:
goto out;
}
+ parent = 0;
+ root_objectid = 0;
+ owner = 0;
+ owner_offset = 0;
/* Now check every backref in this extent item */
iref = (struct btrfs_extent_inline_ref *)ptr;
type = btrfs_extent_inline_ref_type(eb, iref);
offset = btrfs_extent_inline_ref_offset(eb, iref);
switch (type) {
case BTRFS_TREE_BLOCK_REF_KEY:
+ root_objectid = offset;
+ owner = level;
ret = check_tree_block_backref(fs_info, offset, key.objectid,
level);
err |= ret;
break;
case BTRFS_SHARED_BLOCK_REF_KEY:
+ parent = offset;
ret = check_shared_block_backref(fs_info, offset, key.objectid,
level);
err |= ret;
break;
case BTRFS_EXTENT_DATA_REF_KEY:
dref = (struct btrfs_extent_data_ref *)(&iref->offset);
- ret = check_extent_data_backref(fs_info,
- btrfs_extent_data_ref_root(eb, dref),
- btrfs_extent_data_ref_objectid(eb, dref),
- btrfs_extent_data_ref_offset(eb, dref),
- key.objectid, key.offset,
- btrfs_extent_data_ref_count(eb, dref));
+ root_objectid = btrfs_extent_data_ref_root(eb, dref);
+ owner = btrfs_extent_data_ref_objectid(eb, dref);
+ owner_offset = btrfs_extent_data_ref_offset(eb, dref);
+ ret = check_extent_data_backref(fs_info, root_objectid, owner,
+ owner_offset, key.objectid, key.offset,
+ btrfs_extent_data_ref_count(eb, dref));
err |= ret;
break;
case BTRFS_SHARED_DATA_REF_KEY:
+ parent = offset;
ret = check_shared_data_backref(fs_info, offset, key.objectid);
err |= ret;
break;
default:
error("extent[%llu %d %llu] has unknown ref type: %d",
key.objectid, key.type, key.offset, type);
- err |= UNKNOWN_TYPE;
+ ret = UNKNOWN_TYPE;
+ err |= ret;
goto out;
}
+ if (err && repair) {
+ ret = repair_extent_item(trans, fs_info->extent_root, path,
+ key.objectid, num_bytes, parent, root_objectid,
+ owner, owner_offset, ret);
+ if (ret < 0)
+ goto out;
+ if (ret) {
+ goto next;
+ err = ret;
+ }
+ }
+
ptr += btrfs_extent_inline_ref_size(type);
goto next;
@@ -11571,6 +11647,39 @@ out:
return err;
}
+static int delete_extent_tree_item(struct btrfs_trans_handle *trans,
+ struct btrfs_root *root,
+ struct btrfs_path *path)
+{
+ struct btrfs_key key;
+ int ret = 0;
+
+ btrfs_item_key_to_cpu(path->nodes[0], &key, path->slots[0]);
+ btrfs_release_path(path);
+ ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
+ if (ret) {
+ ret = -ENOENT;
+ goto out;
+ }
+
+ ret = btrfs_del_item(trans, root, path);
+ if (ret)
+ goto out;
+
+ if (path->slots[0] == 0)
+ btrfs_prev_leaf(root, path);
+ else
+ path->slots[0]--;
+out:
+ if (ret)
+ error("failed to delete root %llu item[%llu, %u, %llu]\n",
+ root->objectid, key.objectid, key.type, key.offset);
+ else
+ printf("deleted root %llu item[%llu, %u, %llu]\n",
+ root->objectid, key.objectid, key.type, key.offset);
+ return ret;
+}
+
/*
* Main entry function to check known items and update related accounting info
*/
@@ -11609,6 +11718,9 @@ again:
break;
case BTRFS_BLOCK_GROUP_ITEM_KEY:
ret = check_block_group_item(fs_info, eb, slot);
+ if (repair &&
+ ret & REFERENCER_MISSING)
+ ret = delete_extent_tree_item(trans, root, path);
err |= ret;
break;
case BTRFS_DEV_ITEM_KEY:
@@ -11625,7 +11737,7 @@ again:
break;
case BTRFS_EXTENT_ITEM_KEY:
case BTRFS_METADATA_ITEM_KEY:
- ret = check_extent_item(fs_info, eb, slot);
+ ret = check_extent_item(trans, fs_info, path);
err |= ret;
break;
case BTRFS_EXTENT_CSUM_KEY:
@@ -11635,6 +11747,9 @@ again:
case BTRFS_TREE_BLOCK_REF_KEY:
ret = check_tree_block_backref(fs_info, key.offset,
key.objectid, -1);
+ if (repair &&
+ ret & (REFERENCER_MISMATCH | REFERENCER_MISSING))
+ ret = delete_extent_tree_item(trans, root, path);
err |= ret;
break;
case BTRFS_EXTENT_DATA_REF_KEY:
@@ -11645,16 +11760,26 @@ again:
btrfs_extent_data_ref_offset(eb, dref),
key.objectid, 0,
btrfs_extent_data_ref_count(eb, dref));
+ if (repair &&
+ ret & (REFERENCER_MISMATCH | REFERENCER_MISSING))
+ ret = delete_extent_tree_item(trans, root, path);
err |= ret;
break;
case BTRFS_SHARED_BLOCK_REF_KEY:
ret = check_shared_block_backref(fs_info, key.offset,
key.objectid, -1);
+ if (repair &&
+ ret & (REFERENCER_MISMATCH | REFERENCER_MISSING))
+ ret = delete_extent_tree_item(trans, root, path);
err |= ret;
break;
case BTRFS_SHARED_DATA_REF_KEY:
ret = check_shared_data_backref(fs_info, key.offset,
key.objectid);
+ if (repair &&
+ ret & (REFERENCER_MISMATCH | REFERENCER_MISSING))
+ ret = delete_extent_tree_item(trans, root, path);
+
err |= ret;
break;
default:
--
2.7.4
--
To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in
the body of a message to majord...@vger.kernel.org
More majordomo info at http://vger.kernel.org/majordomo-info.html
