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-rw-r--r--fs/btrfs/delayed-ref.c101
1 files changed, 0 insertions, 101 deletions
diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c
index 902ce50..e807b14 100644
--- a/fs/btrfs/delayed-ref.c
+++ b/fs/btrfs/delayed-ref.c
@@ -319,107 +319,6 @@ out:
}
/*
- * helper function to lookup reference count and flags of extent.
- *
- * the head node for delayed ref is used to store the sum of all the
- * reference count modifications queued up in the rbtree. the head
- * node may also store the extent flags to set. This way you can check
- * to see what the reference count and extent flags would be if all of
- * the delayed refs are not processed.
- */
-int btrfs_lookup_extent_info(struct btrfs_trans_handle *trans,
- struct btrfs_root *root, u64 bytenr,
- u64 num_bytes, u64 *refs, u64 *flags)
-{
- struct btrfs_delayed_ref_node *ref;
- struct btrfs_delayed_ref_head *head;
- struct btrfs_delayed_ref_root *delayed_refs;
- struct btrfs_path *path;
- struct btrfs_extent_item *ei;
- struct extent_buffer *leaf;
- struct btrfs_key key;
- u32 item_size;
- u64 num_refs;
- u64 extent_flags;
- int ret;
-
- path = btrfs_alloc_path();
- if (!path)
- return -ENOMEM;
-
- key.objectid = bytenr;
- key.type = BTRFS_EXTENT_ITEM_KEY;
- key.offset = num_bytes;
- delayed_refs = &trans->transaction->delayed_refs;
-again:
- ret = btrfs_search_slot(trans, root->fs_info->extent_root,
- &key, path, 0, 0);
- if (ret < 0)
- goto out;
-
- if (ret == 0) {
- leaf = path->nodes[0];
- item_size = btrfs_item_size_nr(leaf, path->slots[0]);
- if (item_size >= sizeof(*ei)) {
- ei = btrfs_item_ptr(leaf, path->slots[0],
- struct btrfs_extent_item);
- num_refs = btrfs_extent_refs(leaf, ei);
- extent_flags = btrfs_extent_flags(leaf, ei);
- } else {
-#ifdef BTRFS_COMPAT_EXTENT_TREE_V0
- struct btrfs_extent_item_v0 *ei0;
- BUG_ON(item_size != sizeof(*ei0));
- ei0 = btrfs_item_ptr(leaf, path->slots[0],
- struct btrfs_extent_item_v0);
- num_refs = btrfs_extent_refs_v0(leaf, ei0);
- /* FIXME: this isn't correct for data */
- extent_flags = BTRFS_BLOCK_FLAG_FULL_BACKREF;
-#else
- BUG();
-#endif
- }
- BUG_ON(num_refs == 0);
- } else {
- num_refs = 0;
- extent_flags = 0;
- ret = 0;
- }
-
- spin_lock(&delayed_refs->lock);
- ref = find_ref_head(&delayed_refs->root, bytenr, NULL);
- if (ref) {
- head = btrfs_delayed_node_to_head(ref);
- if (!mutex_trylock(&head->mutex)) {
- atomic_inc(&ref->refs);
- spin_unlock(&delayed_refs->lock);
-
- btrfs_release_path(root->fs_info->extent_root, path);
-
- mutex_lock(&head->mutex);
- mutex_unlock(&head->mutex);
- btrfs_put_delayed_ref(ref);
- goto again;
- }
- if (head->extent_op && head->extent_op->update_flags)
- extent_flags |= head->extent_op->flags_to_set;
- else
- BUG_ON(num_refs == 0);
-
- num_refs += ref->ref_mod;
- mutex_unlock(&head->mutex);
- }
- WARN_ON(num_refs == 0);
- if (refs)
- *refs = num_refs;
- if (flags)
- *flags = extent_flags;
-out:
- spin_unlock(&delayed_refs->lock);
- btrfs_free_path(path);
- return ret;
-}
-
-/*
* helper function to update an extent delayed ref in the
* rbtree. existing and update must both have the same
* bytenr and parent
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