Btrfs: Full back reference support
This patch makes the back reference system to explicit record the
location of parent node for all types of extents. The location of
parent node is placed into the offset field of backref key. Every
time a tree block is balanced, the back references for the affected
lower level extents are updated.
Signed-off-by: Chris Mason <chris.mason@oracle.com>
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c
index f84b5f6..4c6e0c15 100644
--- a/fs/btrfs/ioctl.c
+++ b/fs/btrfs/ioctl.c
@@ -76,9 +76,8 @@
if (ret)
goto fail;
- leaf = btrfs_alloc_free_block(trans, root, root->leafsize,
- objectid, trans->transid, 0, 0,
- 0, 0);
+ leaf = btrfs_alloc_free_block(trans, root, root->leafsize, 0,
+ objectid, trans->transid, 0, 0, 0);
if (IS_ERR(leaf)) {
ret = PTR_ERR(leaf);
goto fail;
@@ -525,13 +524,10 @@
struct file *src_file;
struct inode *src;
struct btrfs_trans_handle *trans;
- struct btrfs_ordered_extent *ordered;
struct btrfs_path *path;
struct extent_buffer *leaf;
char *buf;
struct btrfs_key key;
- struct btrfs_key new_key;
- u32 size;
u32 nritems;
int slot;
int ret;
@@ -576,6 +572,7 @@
/* do any pending delalloc/csum calc on src, one way or
another, and lock file content */
while (1) {
+ struct btrfs_ordered_extent *ordered;
lock_extent(&BTRFS_I(src)->io_tree, 0, (u64)-1, GFP_NOFS);
ordered = btrfs_lookup_first_ordered_extent(inode, (u64)-1);
if (BTRFS_I(src)->delalloc_bytes == 0 && !ordered)
@@ -619,6 +616,32 @@
key.objectid != src->i_ino)
break;
+ if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY ||
+ btrfs_key_type(&key) == BTRFS_CSUM_ITEM_KEY) {
+ u32 size;
+ struct btrfs_key new_key;
+
+ size = btrfs_item_size_nr(leaf, slot);
+ read_extent_buffer(leaf, buf,
+ btrfs_item_ptr_offset(leaf, slot),
+ size);
+ btrfs_release_path(root, path);
+
+ memcpy(&new_key, &key, sizeof(new_key));
+ new_key.objectid = inode->i_ino;
+ ret = btrfs_insert_empty_item(trans, root, path,
+ &new_key, size);
+ if (ret)
+ goto out;
+
+ leaf = path->nodes[0];
+ slot = path->slots[0];
+ write_extent_buffer(leaf, buf,
+ btrfs_item_ptr_offset(leaf, slot),
+ size);
+ btrfs_mark_buffer_dirty(leaf);
+ }
+
if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY) {
struct btrfs_file_extent_item *extent;
int found_type;
@@ -634,31 +657,15 @@
/* ds == 0 means there's a hole */
if (ds != 0) {
ret = btrfs_inc_extent_ref(trans, root,
- ds, dl,
+ ds, dl, leaf->start,
root->root_key.objectid,
trans->transid,
inode->i_ino, key.offset);
- if (ret)
- goto out;
+ BUG_ON(ret);
}
}
}
-
- if (btrfs_key_type(&key) == BTRFS_EXTENT_DATA_KEY ||
- btrfs_key_type(&key) == BTRFS_CSUM_ITEM_KEY) {
- size = btrfs_item_size_nr(leaf, slot);
- read_extent_buffer(leaf, buf,
- btrfs_item_ptr_offset(leaf, slot),
- size);
- btrfs_release_path(root, path);
- memcpy(&new_key, &key, sizeof(new_key));
- new_key.objectid = inode->i_ino;
- ret = btrfs_insert_item(trans, root, &new_key,
- buf, size);
- BUG_ON(ret);
- } else {
- btrfs_release_path(root, path);
- }
+ btrfs_release_path(root, path);
key.offset++;
}
ret = 0;