Btrfs: Mixed back reference (FORWARD ROLLING FORMAT CHANGE)
[linux-3.10.git] / fs / btrfs / delayed-ref.c
index d6c01c0..84e6781 100644 (file)
  * add extents in the middle of btrfs_search_slot, and it allows
  * us to buffer up frequently modified backrefs in an rb tree instead
  * of hammering updates on the extent allocation tree.
- *
- * Right now this code is only used for reference counted trees, but
- * the long term goal is to get rid of the similar code for delayed
- * extent tree modifications.
  */
 
 /*
- * entries in the rb tree are ordered by the byte number of the extent
- * and by the byte number of the parent block.
+ * compare two delayed tree backrefs with same bytenr and type
+ */
+static int comp_tree_refs(struct btrfs_delayed_tree_ref *ref2,
+                         struct btrfs_delayed_tree_ref *ref1)
+{
+       if (ref1->node.type == BTRFS_TREE_BLOCK_REF_KEY) {
+               if (ref1->root < ref2->root)
+                       return -1;
+               if (ref1->root > ref2->root)
+                       return 1;
+       } else {
+               if (ref1->parent < ref2->parent)
+                       return -1;
+               if (ref1->parent > ref2->parent)
+                       return 1;
+       }
+       return 0;
+}
+
+/*
+ * compare two delayed data backrefs with same bytenr and type
  */
-static int comp_entry(struct btrfs_delayed_ref_node *ref,
-                     u64 bytenr, u64 parent)
+static int comp_data_refs(struct btrfs_delayed_data_ref *ref2,
+                         struct btrfs_delayed_data_ref *ref1)
 {
-       if (bytenr < ref->bytenr)
+       if (ref1->node.type == BTRFS_EXTENT_DATA_REF_KEY) {
+               if (ref1->root < ref2->root)
+                       return -1;
+               if (ref1->root > ref2->root)
+                       return 1;
+               if (ref1->objectid < ref2->objectid)
+                       return -1;
+               if (ref1->objectid > ref2->objectid)
+                       return 1;
+               if (ref1->offset < ref2->offset)
+                       return -1;
+               if (ref1->offset > ref2->offset)
+                       return 1;
+       } else {
+               if (ref1->parent < ref2->parent)
+                       return -1;
+               if (ref1->parent > ref2->parent)
+                       return 1;
+       }
+       return 0;
+}
+
+/*
+ * entries in the rb tree are ordered by the byte number of the extent,
+ * type of the delayed backrefs and content of delayed backrefs.
+ */
+static int comp_entry(struct btrfs_delayed_ref_node *ref2,
+                     struct btrfs_delayed_ref_node *ref1)
+{
+       if (ref1->bytenr < ref2->bytenr)
                return -1;
-       if (bytenr > ref->bytenr)
+       if (ref1->bytenr > ref2->bytenr)
                return 1;
-       if (parent < ref->parent)
+       if (ref1->is_head && ref2->is_head)
+               return 0;
+       if (ref2->is_head)
                return -1;
-       if (parent > ref->parent)
+       if (ref1->is_head)
                return 1;
+       if (ref1->type < ref2->type)
+               return -1;
+       if (ref1->type > ref2->type)
+               return 1;
+       if (ref1->type == BTRFS_TREE_BLOCK_REF_KEY ||
+           ref1->type == BTRFS_SHARED_BLOCK_REF_KEY) {
+               return comp_tree_refs(btrfs_delayed_node_to_tree_ref(ref2),
+                                     btrfs_delayed_node_to_tree_ref(ref1));
+       } else if (ref1->type == BTRFS_EXTENT_DATA_REF_KEY ||
+                  ref1->type == BTRFS_SHARED_DATA_REF_KEY) {
+               return comp_data_refs(btrfs_delayed_node_to_data_ref(ref2),
+                                     btrfs_delayed_node_to_data_ref(ref1));
+       }
+       BUG();
        return 0;
 }
 
@@ -59,20 +119,21 @@ static int comp_entry(struct btrfs_delayed_ref_node *ref,
  * inserted.
  */
 static struct btrfs_delayed_ref_node *tree_insert(struct rb_root *root,
-                                                 u64 bytenr, u64 parent,
                                                  struct rb_node *node)
 {
        struct rb_node **p = &root->rb_node;
        struct rb_node *parent_node = NULL;
        struct btrfs_delayed_ref_node *entry;
+       struct btrfs_delayed_ref_node *ins;
        int cmp;
 
+       ins = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
        while (*p) {
                parent_node = *p;
                entry = rb_entry(parent_node, struct btrfs_delayed_ref_node,
                                 rb_node);
 
-               cmp = comp_entry(entry, bytenr, parent);
+               cmp = comp_entry(entry, ins);
                if (cmp < 0)
                        p = &(*p)->rb_left;
                else if (cmp > 0)
@@ -81,18 +142,17 @@ static struct btrfs_delayed_ref_node *tree_insert(struct rb_root *root,
                        return entry;
        }
 
-       entry = rb_entry(node, struct btrfs_delayed_ref_node, rb_node);
        rb_link_node(node, parent_node, p);
        rb_insert_color(node, root);
        return NULL;
 }
 
 /*
- * find an entry based on (bytenr,parent).  This returns the delayed
- * ref if it was able to find one, or NULL if nothing was in that spot
+ * find an head entry based on bytenr. This returns the delayed ref
+ * head if it was able to find one, or NULL if nothing was in that spot
  */
-static struct btrfs_delayed_ref_node *tree_search(struct rb_root *root,
-                                 u64 bytenr, u64 parent,
+static struct btrfs_delayed_ref_node *find_ref_head(struct rb_root *root,
+                                 u64 bytenr,
                                  struct btrfs_delayed_ref_node **last)
 {
        struct rb_node *n = root->rb_node;
@@ -105,7 +165,15 @@ static struct btrfs_delayed_ref_node *tree_search(struct rb_root *root,
                if (last)
                        *last = entry;
 
-               cmp = comp_entry(entry, bytenr, parent);
+               if (bytenr < entry->bytenr)
+                       cmp = -1;
+               else if (bytenr > entry->bytenr)
+                       cmp = 1;
+               else if (!btrfs_delayed_ref_is_head(entry))
+                       cmp = 1;
+               else
+                       cmp = 0;
+
                if (cmp < 0)
                        n = n->rb_left;
                else if (cmp > 0)
@@ -154,7 +222,7 @@ int btrfs_find_ref_cluster(struct btrfs_trans_handle *trans,
                node = rb_first(&delayed_refs->root);
        } else {
                ref = NULL;
-               tree_search(&delayed_refs->root, start, (u64)-1, &ref);
+               find_ref_head(&delayed_refs->root, start, &ref);
                if (ref) {
                        struct btrfs_delayed_ref_node *tmp;
 
@@ -234,7 +302,7 @@ int btrfs_delayed_ref_pending(struct btrfs_trans_handle *trans, u64 bytenr)
        delayed_refs = &trans->transaction->delayed_refs;
        spin_lock(&delayed_refs->lock);
 
-       ref = tree_search(&delayed_refs->root, bytenr, (u64)-1, NULL);
+       ref = find_ref_head(&delayed_refs->root, bytenr, NULL);
        if (ref) {
                prev_node = rb_prev(&ref->rb_node);
                if (!prev_node)
@@ -250,25 +318,28 @@ out:
 }
 
 /*
- * helper function to lookup reference count
+ * 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.  This way you
- * can check to see what the reference count would be if all of the
- * delayed refs are processed.
+ * 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_ref(struct btrfs_trans_handle *trans,
-                           struct btrfs_root *root, u64 bytenr,
-                           u64 num_bytes, u32 *refs)
+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 extent_buffer *leaf;
        struct btrfs_extent_item *ei;
+       struct extent_buffer *leaf;
        struct btrfs_key key;
-       u32 num_refs;
+       u32 item_size;
+       u64 num_refs;
+       u64 extent_flags;
        int ret;
 
        path = btrfs_alloc_path();
@@ -287,37 +358,60 @@ again:
 
        if (ret == 0) {
                leaf = path->nodes[0];
-               ei = btrfs_item_ptr(leaf, path->slots[0],
-                                   struct btrfs_extent_item);
-               num_refs = btrfs_extent_refs(leaf, ei);
+               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 = tree_search(&delayed_refs->root, bytenr, (u64)-1, NULL);
+       ref = find_ref_head(&delayed_refs->root, bytenr, NULL);
        if (ref) {
                head = btrfs_delayed_node_to_head(ref);
-               if (mutex_trylock(&head->mutex)) {
-                       num_refs += ref->ref_mod;
-                       mutex_unlock(&head->mutex);
-                       *refs = num_refs;
-                       goto out;
-               }
+               if (!mutex_trylock(&head->mutex)) {
+                       atomic_inc(&ref->refs);
+                       spin_unlock(&delayed_refs->lock);
 
-               atomic_inc(&ref->refs);
-               spin_unlock(&delayed_refs->lock);
+                       btrfs_release_path(root->fs_info->extent_root, path);
 
-               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);
 
-               mutex_lock(&head->mutex);
+               num_refs += ref->ref_mod;
                mutex_unlock(&head->mutex);
-               btrfs_put_delayed_ref(ref);
-               goto again;
-       } else {
-               *refs = num_refs;
        }
+       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);
@@ -338,16 +432,7 @@ update_existing_ref(struct btrfs_trans_handle *trans,
                    struct btrfs_delayed_ref_node *existing,
                    struct btrfs_delayed_ref_node *update)
 {
-       struct btrfs_delayed_ref *existing_ref;
-       struct btrfs_delayed_ref *ref;
-
-       existing_ref = btrfs_delayed_node_to_ref(existing);
-       ref = btrfs_delayed_node_to_ref(update);
-
-       if (ref->pin)
-               existing_ref->pin = 1;
-
-       if (ref->action != existing_ref->action) {
+       if (update->action != existing->action) {
                /*
                 * this is effectively undoing either an add or a
                 * drop.  We decrement the ref_mod, and if it goes
@@ -363,20 +448,13 @@ update_existing_ref(struct btrfs_trans_handle *trans,
                        delayed_refs->num_entries--;
                        if (trans->delayed_ref_updates)
                                trans->delayed_ref_updates--;
+               } else {
+                       WARN_ON(existing->type == BTRFS_TREE_BLOCK_REF_KEY ||
+                               existing->type == BTRFS_SHARED_BLOCK_REF_KEY);
                }
        } else {
-               if (existing_ref->action == BTRFS_ADD_DELAYED_REF) {
-                       /* if we're adding refs, make sure all the
-                        * details match up.  The extent could
-                        * have been totally freed and reallocated
-                        * by a different owner before the delayed
-                        * ref entries were removed.
-                        */
-                       existing_ref->owner_objectid = ref->owner_objectid;
-                       existing_ref->generation = ref->generation;
-                       existing_ref->root = ref->root;
-                       existing->num_bytes = update->num_bytes;
-               }
+               WARN_ON(existing->type == BTRFS_TREE_BLOCK_REF_KEY ||
+                       existing->type == BTRFS_SHARED_BLOCK_REF_KEY);
                /*
                 * the action on the existing ref matches
                 * the action on the ref we're trying to add.
@@ -401,6 +479,7 @@ update_existing_head_ref(struct btrfs_delayed_ref_node *existing,
 
        existing_ref = btrfs_delayed_node_to_head(existing);
        ref = btrfs_delayed_node_to_head(update);
+       BUG_ON(existing_ref->is_data != ref->is_data);
 
        if (ref->must_insert_reserved) {
                /* if the extent was freed and then
@@ -420,6 +499,24 @@ update_existing_head_ref(struct btrfs_delayed_ref_node *existing,
 
        }
 
+       if (ref->extent_op) {
+               if (!existing_ref->extent_op) {
+                       existing_ref->extent_op = ref->extent_op;
+               } else {
+                       if (ref->extent_op->update_key) {
+                               memcpy(&existing_ref->extent_op->key,
+                                      &ref->extent_op->key,
+                                      sizeof(ref->extent_op->key));
+                               existing_ref->extent_op->update_key = 1;
+                       }
+                       if (ref->extent_op->update_flags) {
+                               existing_ref->extent_op->flags_to_set |=
+                                       ref->extent_op->flags_to_set;
+                               existing_ref->extent_op->update_flags = 1;
+                       }
+                       kfree(ref->extent_op);
+               }
+       }
        /*
         * update the reference mod on the head to reflect this new operation
         */
@@ -427,19 +524,16 @@ update_existing_head_ref(struct btrfs_delayed_ref_node *existing,
 }
 
 /*
- * helper function to actually insert a delayed ref into the rbtree.
+ * helper function to actually insert a head node into the rbtree.
  * this does all the dirty work in terms of maintaining the correct
- * overall modification count in the head node and properly dealing
- * with updating existing nodes as new modifications are queued.
+ * overall modification count.
  */
-static noinline int __btrfs_add_delayed_ref(struct btrfs_trans_handle *trans,
-                         struct btrfs_delayed_ref_node *ref,
-                         u64 bytenr, u64 num_bytes, u64 parent, u64 ref_root,
-                         u64 ref_generation, u64 owner_objectid, int action,
-                         int pin)
+static noinline int add_delayed_ref_head(struct btrfs_trans_handle *trans,
+                                       struct btrfs_delayed_ref_node *ref,
+                                       u64 bytenr, u64 num_bytes,
+                                       int action, int is_data)
 {
        struct btrfs_delayed_ref_node *existing;
-       struct btrfs_delayed_ref *full_ref;
        struct btrfs_delayed_ref_head *head_ref = NULL;
        struct btrfs_delayed_ref_root *delayed_refs;
        int count_mod = 1;
@@ -449,12 +543,10 @@ static noinline int __btrfs_add_delayed_ref(struct btrfs_trans_handle *trans,
         * the head node stores the sum of all the mods, so dropping a ref
         * should drop the sum in the head node by one.
         */
-       if (parent == (u64)-1) {
-               if (action == BTRFS_DROP_DELAYED_REF)
-                       count_mod = -1;
-               else if (action == BTRFS_UPDATE_DELAYED_HEAD)
-                       count_mod = 0;
-       }
+       if (action == BTRFS_UPDATE_DELAYED_HEAD)
+               count_mod = 0;
+       else if (action == BTRFS_DROP_DELAYED_REF)
+               count_mod = -1;
 
        /*
         * BTRFS_ADD_DELAYED_EXTENT means that we need to update
@@ -467,57 +559,148 @@ static noinline int __btrfs_add_delayed_ref(struct btrfs_trans_handle *trans,
         * Once we record must_insert_reserved, switch the action to
         * BTRFS_ADD_DELAYED_REF because other special casing is not required.
         */
-       if (action == BTRFS_ADD_DELAYED_EXTENT) {
+       if (action == BTRFS_ADD_DELAYED_EXTENT)
                must_insert_reserved = 1;
-               action = BTRFS_ADD_DELAYED_REF;
-       } else {
+       else
                must_insert_reserved = 0;
-       }
-
 
        delayed_refs = &trans->transaction->delayed_refs;
 
        /* first set the basic ref node struct up */
        atomic_set(&ref->refs, 1);
        ref->bytenr = bytenr;
-       ref->parent = parent;
+       ref->num_bytes = num_bytes;
        ref->ref_mod = count_mod;
+       ref->type  = 0;
+       ref->action  = 0;
+       ref->is_head = 1;
        ref->in_tree = 1;
+
+       head_ref = btrfs_delayed_node_to_head(ref);
+       head_ref->must_insert_reserved = must_insert_reserved;
+       head_ref->is_data = is_data;
+
+       INIT_LIST_HEAD(&head_ref->cluster);
+       mutex_init(&head_ref->mutex);
+
+       existing = tree_insert(&delayed_refs->root, &ref->rb_node);
+
+       if (existing) {
+               update_existing_head_ref(existing, ref);
+               /*
+                * we've updated the existing ref, free the newly
+                * allocated ref
+                */
+               kfree(ref);
+       } else {
+               delayed_refs->num_heads++;
+               delayed_refs->num_heads_ready++;
+               delayed_refs->num_entries++;
+               trans->delayed_ref_updates++;
+       }
+       return 0;
+}
+
+/*
+ * helper to insert a delayed tree ref into the rbtree.
+ */
+static noinline int add_delayed_tree_ref(struct btrfs_trans_handle *trans,
+                                        struct btrfs_delayed_ref_node *ref,
+                                        u64 bytenr, u64 num_bytes, u64 parent,
+                                        u64 ref_root, int level, int action)
+{
+       struct btrfs_delayed_ref_node *existing;
+       struct btrfs_delayed_tree_ref *full_ref;
+       struct btrfs_delayed_ref_root *delayed_refs;
+
+       if (action == BTRFS_ADD_DELAYED_EXTENT)
+               action = BTRFS_ADD_DELAYED_REF;
+
+       delayed_refs = &trans->transaction->delayed_refs;
+
+       /* first set the basic ref node struct up */
+       atomic_set(&ref->refs, 1);
+       ref->bytenr = bytenr;
        ref->num_bytes = num_bytes;
+       ref->ref_mod = 1;
+       ref->action = action;
+       ref->is_head = 0;
+       ref->in_tree = 1;
 
-       if (btrfs_delayed_ref_is_head(ref)) {
-               head_ref = btrfs_delayed_node_to_head(ref);
-               head_ref->must_insert_reserved = must_insert_reserved;
-               INIT_LIST_HEAD(&head_ref->cluster);
-               mutex_init(&head_ref->mutex);
+       full_ref = btrfs_delayed_node_to_tree_ref(ref);
+       if (parent) {
+               full_ref->parent = parent;
+               ref->type = BTRFS_SHARED_BLOCK_REF_KEY;
        } else {
-               full_ref = btrfs_delayed_node_to_ref(ref);
                full_ref->root = ref_root;
-               full_ref->generation = ref_generation;
-               full_ref->owner_objectid = owner_objectid;
-               full_ref->pin = pin;
-               full_ref->action = action;
+               ref->type = BTRFS_TREE_BLOCK_REF_KEY;
        }
+       full_ref->level = level;
 
-       existing = tree_insert(&delayed_refs->root, bytenr,
-                              parent, &ref->rb_node);
+       existing = tree_insert(&delayed_refs->root, &ref->rb_node);
 
        if (existing) {
-               if (btrfs_delayed_ref_is_head(ref))
-                       update_existing_head_ref(existing, ref);
-               else
-                       update_existing_ref(trans, delayed_refs, existing, ref);
+               update_existing_ref(trans, delayed_refs, existing, ref);
+               /*
+                * we've updated the existing ref, free the newly
+                * allocated ref
+                */
+               kfree(ref);
+       } else {
+               delayed_refs->num_entries++;
+               trans->delayed_ref_updates++;
+       }
+       return 0;
+}
+
+/*
+ * helper to insert a delayed data ref into the rbtree.
+ */
+static noinline int add_delayed_data_ref(struct btrfs_trans_handle *trans,
+                                        struct btrfs_delayed_ref_node *ref,
+                                        u64 bytenr, u64 num_bytes, u64 parent,
+                                        u64 ref_root, u64 owner, u64 offset,
+                                        int action)
+{
+       struct btrfs_delayed_ref_node *existing;
+       struct btrfs_delayed_data_ref *full_ref;
+       struct btrfs_delayed_ref_root *delayed_refs;
+
+       if (action == BTRFS_ADD_DELAYED_EXTENT)
+               action = BTRFS_ADD_DELAYED_REF;
+
+       delayed_refs = &trans->transaction->delayed_refs;
+
+       /* first set the basic ref node struct up */
+       atomic_set(&ref->refs, 1);
+       ref->bytenr = bytenr;
+       ref->num_bytes = num_bytes;
+       ref->ref_mod = 1;
+       ref->action = action;
+       ref->is_head = 0;
+       ref->in_tree = 1;
+
+       full_ref = btrfs_delayed_node_to_data_ref(ref);
+       if (parent) {
+               full_ref->parent = parent;
+               ref->type = BTRFS_SHARED_DATA_REF_KEY;
+       } else {
+               full_ref->root = ref_root;
+               ref->type = BTRFS_EXTENT_DATA_REF_KEY;
+       }
+       full_ref->objectid = owner;
+       full_ref->offset = offset;
 
+       existing = tree_insert(&delayed_refs->root, &ref->rb_node);
+
+       if (existing) {
+               update_existing_ref(trans, delayed_refs, existing, ref);
                /*
                 * we've updated the existing ref, free the newly
                 * allocated ref
                 */
                kfree(ref);
        } else {
-               if (btrfs_delayed_ref_is_head(ref)) {
-                       delayed_refs->num_heads++;
-                       delayed_refs->num_heads_ready++;
-               }
                delayed_refs->num_entries++;
                trans->delayed_ref_updates++;
        }
@@ -525,37 +708,78 @@ static noinline int __btrfs_add_delayed_ref(struct btrfs_trans_handle *trans,
 }
 
 /*
- * add a delayed ref to the tree.  This does all of the accounting required
+ * add a delayed tree ref.  This does all of the accounting required
  * to make sure the delayed ref is eventually processed before this
  * transaction commits.
  */
-int btrfs_add_delayed_ref(struct btrfs_trans_handle *trans,
-                         u64 bytenr, u64 num_bytes, u64 parent, u64 ref_root,
-                         u64 ref_generation, u64 owner_objectid, int action,
-                         int pin)
+int btrfs_add_delayed_tree_ref(struct btrfs_trans_handle *trans,
+                              u64 bytenr, u64 num_bytes, u64 parent,
+                              u64 ref_root,  int level, int action,
+                              struct btrfs_delayed_extent_op *extent_op)
 {
-       struct btrfs_delayed_ref *ref;
+       struct btrfs_delayed_tree_ref *ref;
        struct btrfs_delayed_ref_head *head_ref;
        struct btrfs_delayed_ref_root *delayed_refs;
        int ret;
 
+       BUG_ON(extent_op && extent_op->is_data);
        ref = kmalloc(sizeof(*ref), GFP_NOFS);
        if (!ref)
                return -ENOMEM;
 
+       head_ref = kmalloc(sizeof(*head_ref), GFP_NOFS);
+       if (!head_ref) {
+               kfree(ref);
+               return -ENOMEM;
+       }
+
+       head_ref->extent_op = extent_op;
+
+       delayed_refs = &trans->transaction->delayed_refs;
+       spin_lock(&delayed_refs->lock);
+
        /*
-        * the parent = 0 case comes from cases where we don't actually
-        * know the parent yet.  It will get updated later via a add/drop
-        * pair.
+        * insert both the head node and the new ref without dropping
+        * the spin lock
         */
-       if (parent == 0)
-               parent = bytenr;
+       ret = add_delayed_ref_head(trans, &head_ref->node, bytenr, num_bytes,
+                                  action, 0);
+       BUG_ON(ret);
+
+       ret = add_delayed_tree_ref(trans, &ref->node, bytenr, num_bytes,
+                                  parent, ref_root, level, action);
+       BUG_ON(ret);
+       spin_unlock(&delayed_refs->lock);
+       return 0;
+}
+
+/*
+ * add a delayed data ref. it's similar to btrfs_add_delayed_tree_ref.
+ */
+int btrfs_add_delayed_data_ref(struct btrfs_trans_handle *trans,
+                              u64 bytenr, u64 num_bytes,
+                              u64 parent, u64 ref_root,
+                              u64 owner, u64 offset, int action,
+                              struct btrfs_delayed_extent_op *extent_op)
+{
+       struct btrfs_delayed_data_ref *ref;
+       struct btrfs_delayed_ref_head *head_ref;
+       struct btrfs_delayed_ref_root *delayed_refs;
+       int ret;
+
+       BUG_ON(extent_op && !extent_op->is_data);
+       ref = kmalloc(sizeof(*ref), GFP_NOFS);
+       if (!ref)
+               return -ENOMEM;
 
        head_ref = kmalloc(sizeof(*head_ref), GFP_NOFS);
        if (!head_ref) {
                kfree(ref);
                return -ENOMEM;
        }
+
+       head_ref->extent_op = extent_op;
+
        delayed_refs = &trans->transaction->delayed_refs;
        spin_lock(&delayed_refs->lock);
 
@@ -563,14 +787,39 @@ int btrfs_add_delayed_ref(struct btrfs_trans_handle *trans,
         * insert both the head node and the new ref without dropping
         * the spin lock
         */
-       ret = __btrfs_add_delayed_ref(trans, &head_ref->node, bytenr, num_bytes,
-                                     (u64)-1, 0, 0, 0, action, pin);
+       ret = add_delayed_ref_head(trans, &head_ref->node, bytenr, num_bytes,
+                                  action, 1);
        BUG_ON(ret);
 
-       ret = __btrfs_add_delayed_ref(trans, &ref->node, bytenr, num_bytes,
-                                     parent, ref_root, ref_generation,
-                                     owner_objectid, action, pin);
+       ret = add_delayed_data_ref(trans, &ref->node, bytenr, num_bytes,
+                                  parent, ref_root, owner, offset, action);
+       BUG_ON(ret);
+       spin_unlock(&delayed_refs->lock);
+       return 0;
+}
+
+int btrfs_add_delayed_extent_op(struct btrfs_trans_handle *trans,
+                               u64 bytenr, u64 num_bytes,
+                               struct btrfs_delayed_extent_op *extent_op)
+{
+       struct btrfs_delayed_ref_head *head_ref;
+       struct btrfs_delayed_ref_root *delayed_refs;
+       int ret;
+
+       head_ref = kmalloc(sizeof(*head_ref), GFP_NOFS);
+       if (!head_ref)
+               return -ENOMEM;
+
+       head_ref->extent_op = extent_op;
+
+       delayed_refs = &trans->transaction->delayed_refs;
+       spin_lock(&delayed_refs->lock);
+
+       ret = add_delayed_ref_head(trans, &head_ref->node, bytenr,
+                                  num_bytes, BTRFS_UPDATE_DELAYED_HEAD,
+                                  extent_op->is_data);
        BUG_ON(ret);
+
        spin_unlock(&delayed_refs->lock);
        return 0;
 }
@@ -587,7 +836,7 @@ btrfs_find_delayed_ref_head(struct btrfs_trans_handle *trans, u64 bytenr)
        struct btrfs_delayed_ref_root *delayed_refs;
 
        delayed_refs = &trans->transaction->delayed_refs;
-       ref = tree_search(&delayed_refs->root, bytenr, (u64)-1, NULL);
+       ref = find_ref_head(&delayed_refs->root, bytenr, NULL);
        if (ref)
                return btrfs_delayed_node_to_head(ref);
        return NULL;
@@ -603,6 +852,7 @@ btrfs_find_delayed_ref_head(struct btrfs_trans_handle *trans, u64 bytenr)
  *
  * It is the same as doing a ref add and delete in two separate calls.
  */
+#if 0
 int btrfs_update_delayed_ref(struct btrfs_trans_handle *trans,
                          u64 bytenr, u64 num_bytes, u64 orig_parent,
                          u64 parent, u64 orig_ref_root, u64 ref_root,
@@ -666,3 +916,4 @@ int btrfs_update_delayed_ref(struct btrfs_trans_handle *trans,
        spin_unlock(&delayed_refs->lock);
        return 0;
 }
+#endif