cifs: refactor new_inode() calls and inode initialization
[safe/jmp/linux-2.6] / fs / btrfs / extent-tree.c
index 2451717..293da65 100644 (file)
@@ -19,6 +19,8 @@
 #include <linux/pagemap.h>
 #include <linux/writeback.h>
 #include <linux/blkdev.h>
+#include <linux/version.h>
+#include "compat.h"
 #include "hash.h"
 #include "crc32c.h"
 #include "ctree.h"
@@ -28,6 +30,7 @@
 #include "volumes.h"
 #include "locking.h"
 #include "ref-cache.h"
+#include "compat.h"
 
 #define PENDING_EXTENT_INSERT 0
 #define PENDING_EXTENT_DELETE 1
@@ -42,16 +45,21 @@ struct pending_extent_op {
        u64 generation;
        u64 orig_generation;
        int level;
+       struct list_head list;
+       int del;
 };
 
-static int finish_current_insert(struct btrfs_trans_handle *trans, struct
-                                btrfs_root *extent_root, int all);
-static int del_pending_extents(struct btrfs_trans_handle *trans, struct
-                              btrfs_root *extent_root, int all);
-static struct btrfs_block_group_cache *
-__btrfs_find_block_group(struct btrfs_root *root,
-                        struct btrfs_block_group_cache *hint,
-                        u64 search_start, int data, int owner);
+static int finish_current_insert(struct btrfs_trans_handle *trans,
+                                struct btrfs_root *extent_root, int all);
+static int del_pending_extents(struct btrfs_trans_handle *trans,
+                              struct btrfs_root *extent_root, int all);
+static int pin_down_bytes(struct btrfs_trans_handle *trans,
+                         struct btrfs_root *root,
+                         u64 bytenr, u64 num_bytes, int is_data);
+static int update_block_group(struct btrfs_trans_handle *trans,
+                             struct btrfs_root *root,
+                             u64 bytenr, u64 num_bytes, int alloc,
+                             int mark_free);
 
 static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
 {
@@ -62,7 +70,7 @@ static int block_group_bits(struct btrfs_block_group_cache *cache, u64 bits)
  * this adds the block group to the fs_info rb tree for the block group
  * cache
  */
-int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
+static int btrfs_add_block_group_cache(struct btrfs_fs_info *info,
                                struct btrfs_block_group_cache *block_group)
 {
        struct rb_node **p;
@@ -130,6 +138,8 @@ block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
                        break;
                }
        }
+       if (ret)
+               atomic_inc(&ret->count);
        spin_unlock(&info->block_group_cache_lock);
 
        return ret;
@@ -158,8 +168,8 @@ static int add_new_free_space(struct btrfs_block_group_cache *block_group,
                        start = extent_end + 1;
                } else if (extent_start > start && extent_start < end) {
                        size = extent_start - start;
-                       ret = btrfs_add_free_space_lock(block_group, start,
-                                                       size);
+                       ret = btrfs_add_free_space(block_group, start,
+                                                  size);
                        BUG_ON(ret);
                        start = extent_end + 1;
                } else {
@@ -169,7 +179,7 @@ static int add_new_free_space(struct btrfs_block_group_cache *block_group,
 
        if (start < end) {
                size = end - start;
-               ret = btrfs_add_free_space_lock(block_group, start, size);
+               ret = btrfs_add_free_space(block_group, start, size);
                BUG_ON(ret);
        }
        mutex_unlock(&info->pinned_mutex);
@@ -177,6 +187,29 @@ static int add_new_free_space(struct btrfs_block_group_cache *block_group,
        return 0;
 }
 
+static int remove_sb_from_cache(struct btrfs_root *root,
+                               struct btrfs_block_group_cache *cache)
+{
+       u64 bytenr;
+       u64 *logical;
+       int stripe_len;
+       int i, nr, ret;
+
+       for (i = 0; i < BTRFS_SUPER_MIRROR_MAX; i++) {
+               bytenr = btrfs_sb_offset(i);
+               ret = btrfs_rmap_block(&root->fs_info->mapping_tree,
+                                      cache->key.objectid, bytenr, 0,
+                                      &logical, &nr, &stripe_len);
+               BUG_ON(ret);
+               while (nr--) {
+                       btrfs_remove_free_space(cache, logical[nr],
+                                               stripe_len);
+               }
+               kfree(logical);
+       }
+       return 0;
+}
+
 static int cache_block_group(struct btrfs_root *root,
                             struct btrfs_block_group_cache *block_group)
 {
@@ -185,9 +218,7 @@ static int cache_block_group(struct btrfs_root *root,
        struct btrfs_key key;
        struct extent_buffer *leaf;
        int slot;
-       u64 last = 0;
-       u64 first_free;
-       int found = 0;
+       u64 last;
 
        if (!block_group)
                return 0;
@@ -208,24 +239,15 @@ static int cache_block_group(struct btrfs_root *root,
         * skip the locking here
         */
        path->skip_locking = 1;
-       first_free = max_t(u64, block_group->key.objectid,
-                          BTRFS_SUPER_INFO_OFFSET + BTRFS_SUPER_INFO_SIZE);
-       key.objectid = block_group->key.objectid;
+       last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
+       key.objectid = last;
        key.offset = 0;
        btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
        ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
        if (ret < 0)
                goto err;
-       ret = btrfs_previous_item(root, path, 0, BTRFS_EXTENT_ITEM_KEY);
-       if (ret < 0)
-               goto err;
-       if (ret == 0) {
-               leaf = path->nodes[0];
-               btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
-               if (key.objectid + key.offset > first_free)
-                       first_free = key.objectid + key.offset;
-       }
-       while(1) {
+
+       while (1) {
                leaf = path->nodes[0];
                slot = path->slots[0];
                if (slot >= btrfs_header_nritems(leaf)) {
@@ -246,11 +268,6 @@ static int cache_block_group(struct btrfs_root *root,
                        break;
 
                if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) {
-                       if (!found) {
-                               last = first_free;
-                               found = 1;
-                       }
-
                        add_new_free_space(block_group, root->fs_info, last,
                                           key.objectid);
 
@@ -260,13 +277,11 @@ next:
                path->slots[0]++;
        }
 
-       if (!found)
-               last = first_free;
-
        add_new_free_space(block_group, root->fs_info, last,
                           block_group->key.objectid +
                           block_group->key.offset);
 
+       remove_sb_from_cache(root, block_group);
        block_group->cached = 1;
        ret = 0;
 err:
@@ -277,9 +292,8 @@ err:
 /*
  * return the block group that starts at or after bytenr
  */
-struct btrfs_block_group_cache *btrfs_lookup_first_block_group(struct
-                                                      btrfs_fs_info *info,
-                                                        u64 bytenr)
+static struct btrfs_block_group_cache *
+btrfs_lookup_first_block_group(struct btrfs_fs_info *info, u64 bytenr)
 {
        struct btrfs_block_group_cache *cache;
 
@@ -291,9 +305,9 @@ struct btrfs_block_group_cache *btrfs_lookup_first_block_group(struct
 /*
  * return the block group that contains teh given bytenr
  */
-struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
-                                                        btrfs_fs_info *info,
-                                                        u64 bytenr)
+struct btrfs_block_group_cache *btrfs_lookup_block_group(
+                                                struct btrfs_fs_info *info,
+                                                u64 bytenr)
 {
        struct btrfs_block_group_cache *cache;
 
@@ -302,6 +316,12 @@ struct btrfs_block_group_cache *btrfs_lookup_block_group(struct
        return cache;
 }
 
+static inline void put_block_group(struct btrfs_block_group_cache *cache)
+{
+       if (atomic_dec_and_test(&cache->count))
+               kfree(cache);
+}
+
 static struct btrfs_space_info *__find_space_info(struct btrfs_fs_info *info,
                                                  u64 flags)
 {
@@ -325,54 +345,16 @@ static u64 div_factor(u64 num, int factor)
        return num;
 }
 
-static struct btrfs_block_group_cache *
-__btrfs_find_block_group(struct btrfs_root *root,
-                        struct btrfs_block_group_cache *hint,
-                        u64 search_start, int data, int owner)
+u64 btrfs_find_block_group(struct btrfs_root *root,
+                          u64 search_start, u64 search_hint, int owner)
 {
        struct btrfs_block_group_cache *cache;
-       struct btrfs_block_group_cache *found_group = NULL;
-       struct btrfs_fs_info *info = root->fs_info;
        u64 used;
-       u64 last = 0;
-       u64 free_check;
+       u64 last = max(search_hint, search_start);
+       u64 group_start = 0;
        int full_search = 0;
-       int factor = 10;
+       int factor = 9;
        int wrapped = 0;
-
-       if (data & BTRFS_BLOCK_GROUP_METADATA)
-               factor = 9;
-
-       if (search_start) {
-               struct btrfs_block_group_cache *shint;
-               shint = btrfs_lookup_first_block_group(info, search_start);
-               if (shint && block_group_bits(shint, data) && !shint->ro) {
-                       spin_lock(&shint->lock);
-                       used = btrfs_block_group_used(&shint->item);
-                       if (used + shint->pinned + shint->reserved <
-                           div_factor(shint->key.offset, factor)) {
-                               spin_unlock(&shint->lock);
-                               return shint;
-                       }
-                       spin_unlock(&shint->lock);
-               }
-       }
-       if (hint && !hint->ro && block_group_bits(hint, data)) {
-               spin_lock(&hint->lock);
-               used = btrfs_block_group_used(&hint->item);
-               if (used + hint->pinned + hint->reserved <
-                   div_factor(hint->key.offset, factor)) {
-                       spin_unlock(&hint->lock);
-                       return hint;
-               }
-               spin_unlock(&hint->lock);
-               last = hint->key.objectid + hint->key.offset;
-       } else {
-               if (hint)
-                       last = max(hint->key.objectid, search_start);
-               else
-                       last = search_start;
-       }
 again:
        while (1) {
                cache = btrfs_lookup_first_block_group(root->fs_info, last);
@@ -383,16 +365,18 @@ again:
                last = cache->key.objectid + cache->key.offset;
                used = btrfs_block_group_used(&cache->item);
 
-               if (!cache->ro && block_group_bits(cache, data)) {
-                       free_check = div_factor(cache->key.offset, factor);
+               if ((full_search || !cache->ro) &&
+                   block_group_bits(cache, BTRFS_BLOCK_GROUP_METADATA)) {
                        if (used + cache->pinned + cache->reserved <
-                           free_check) {
-                               found_group = cache;
+                           div_factor(cache->key.offset, factor)) {
+                               group_start = cache->key.objectid;
                                spin_unlock(&cache->lock);
+                               put_block_group(cache);
                                goto found;
                        }
                }
                spin_unlock(&cache->lock);
+               put_block_group(cache);
                cond_resched();
        }
        if (!wrapped) {
@@ -407,18 +391,7 @@ again:
                goto again;
        }
 found:
-       return found_group;
-}
-
-struct btrfs_block_group_cache *btrfs_find_block_group(struct btrfs_root *root,
-                                                struct btrfs_block_group_cache
-                                                *hint, u64 search_start,
-                                                int data, int owner)
-{
-
-       struct btrfs_block_group_cache *ret;
-       ret = __btrfs_find_block_group(root, hint, search_start, data, owner);
-       return ret;
+       return group_start;
 }
 
 /* simple helper to search for an existing extent at a given offset */
@@ -518,7 +491,7 @@ int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len)
  * to the key objectid.
  */
 
-static int noinline lookup_extent_backref(struct btrfs_trans_handle *trans,
+static noinline int lookup_extent_backref(struct btrfs_trans_handle *trans,
                                          struct btrfs_root *root,
                                          struct btrfs_path *path,
                                          u64 bytenr, u64 parent,
@@ -559,7 +532,257 @@ out:
        return ret;
 }
 
-static int noinline insert_extent_backref(struct btrfs_trans_handle *trans,
+/*
+ * updates all the backrefs that are pending on update_list for the
+ * extent_root
+ */
+static noinline int update_backrefs(struct btrfs_trans_handle *trans,
+                                   struct btrfs_root *extent_root,
+                                   struct btrfs_path *path,
+                                   struct list_head *update_list)
+{
+       struct btrfs_key key;
+       struct btrfs_extent_ref *ref;
+       struct btrfs_fs_info *info = extent_root->fs_info;
+       struct pending_extent_op *op;
+       struct extent_buffer *leaf;
+       int ret = 0;
+       struct list_head *cur = update_list->next;
+       u64 ref_objectid;
+       u64 ref_root = extent_root->root_key.objectid;
+
+       op = list_entry(cur, struct pending_extent_op, list);
+
+search:
+       key.objectid = op->bytenr;
+       key.type = BTRFS_EXTENT_REF_KEY;
+       key.offset = op->orig_parent;
+
+       ret = btrfs_search_slot(trans, extent_root, &key, path, 0, 1);
+       BUG_ON(ret);
+
+       leaf = path->nodes[0];
+
+loop:
+       ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref);
+
+       ref_objectid = btrfs_ref_objectid(leaf, ref);
+
+       if (btrfs_ref_root(leaf, ref) != ref_root ||
+           btrfs_ref_generation(leaf, ref) != op->orig_generation ||
+           (ref_objectid != op->level &&
+            ref_objectid != BTRFS_MULTIPLE_OBJECTIDS)) {
+               printk(KERN_ERR "btrfs couldn't find %llu, parent %llu, "
+                      "root %llu, owner %u\n",
+                      (unsigned long long)op->bytenr,
+                      (unsigned long long)op->orig_parent,
+                      (unsigned long long)ref_root, op->level);
+               btrfs_print_leaf(extent_root, leaf);
+               BUG();
+       }
+
+       key.objectid = op->bytenr;
+       key.offset = op->parent;
+       key.type = BTRFS_EXTENT_REF_KEY;
+       ret = btrfs_set_item_key_safe(trans, extent_root, path, &key);
+       BUG_ON(ret);
+       ref = btrfs_item_ptr(leaf, path->slots[0], struct btrfs_extent_ref);
+       btrfs_set_ref_generation(leaf, ref, op->generation);
+
+       cur = cur->next;
+
+       list_del_init(&op->list);
+       unlock_extent(&info->extent_ins, op->bytenr,
+                     op->bytenr + op->num_bytes - 1, GFP_NOFS);
+       kfree(op);
+
+       if (cur == update_list) {
+               btrfs_mark_buffer_dirty(path->nodes[0]);
+               btrfs_release_path(extent_root, path);
+               goto out;
+       }
+
+       op = list_entry(cur, struct pending_extent_op, list);
+
+       path->slots[0]++;
+       while (path->slots[0] < btrfs_header_nritems(leaf)) {
+               btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+               if (key.objectid == op->bytenr &&
+                   key.type == BTRFS_EXTENT_REF_KEY)
+                       goto loop;
+               path->slots[0]++;
+       }
+
+       btrfs_mark_buffer_dirty(path->nodes[0]);
+       btrfs_release_path(extent_root, path);
+       goto search;
+
+out:
+       return 0;
+}
+
+static noinline int insert_extents(struct btrfs_trans_handle *trans,
+                                  struct btrfs_root *extent_root,
+                                  struct btrfs_path *path,
+                                  struct list_head *insert_list, int nr)
+{
+       struct btrfs_key *keys;
+       u32 *data_size;
+       struct pending_extent_op *op;
+       struct extent_buffer *leaf;
+       struct list_head *cur = insert_list->next;
+       struct btrfs_fs_info *info = extent_root->fs_info;
+       u64 ref_root = extent_root->root_key.objectid;
+       int i = 0, last = 0, ret;
+       int total = nr * 2;
+
+       if (!nr)
+               return 0;
+
+       keys = kzalloc(total * sizeof(struct btrfs_key), GFP_NOFS);
+       if (!keys)
+               return -ENOMEM;
+
+       data_size = kzalloc(total * sizeof(u32), GFP_NOFS);
+       if (!data_size) {
+               kfree(keys);
+               return -ENOMEM;
+       }
+
+       list_for_each_entry(op, insert_list, list) {
+               keys[i].objectid = op->bytenr;
+               keys[i].offset = op->num_bytes;
+               keys[i].type = BTRFS_EXTENT_ITEM_KEY;
+               data_size[i] = sizeof(struct btrfs_extent_item);
+               i++;
+
+               keys[i].objectid = op->bytenr;
+               keys[i].offset = op->parent;
+               keys[i].type = BTRFS_EXTENT_REF_KEY;
+               data_size[i] = sizeof(struct btrfs_extent_ref);
+               i++;
+       }
+
+       op = list_entry(cur, struct pending_extent_op, list);
+       i = 0;
+       while (i < total) {
+               int c;
+               ret = btrfs_insert_some_items(trans, extent_root, path,
+                                             keys+i, data_size+i, total-i);
+               BUG_ON(ret < 0);
+
+               if (last && ret > 1)
+                       BUG();
+
+               leaf = path->nodes[0];
+               for (c = 0; c < ret; c++) {
+                       int ref_first = keys[i].type == BTRFS_EXTENT_REF_KEY;
+
+                       /*
+                        * if the first item we inserted was a backref, then
+                        * the EXTENT_ITEM will be the odd c's, else it will
+                        * be the even c's
+                        */
+                       if ((ref_first && (c % 2)) ||
+                           (!ref_first && !(c % 2))) {
+                               struct btrfs_extent_item *itm;
+
+                               itm = btrfs_item_ptr(leaf, path->slots[0] + c,
+                                                    struct btrfs_extent_item);
+                               btrfs_set_extent_refs(path->nodes[0], itm, 1);
+                               op->del++;
+                       } else {
+                               struct btrfs_extent_ref *ref;
+
+                               ref = btrfs_item_ptr(leaf, path->slots[0] + c,
+                                                    struct btrfs_extent_ref);
+                               btrfs_set_ref_root(leaf, ref, ref_root);
+                               btrfs_set_ref_generation(leaf, ref,
+                                                        op->generation);
+                               btrfs_set_ref_objectid(leaf, ref, op->level);
+                               btrfs_set_ref_num_refs(leaf, ref, 1);
+                               op->del++;
+                       }
+
+                       /*
+                        * using del to see when its ok to free up the
+                        * pending_extent_op.  In the case where we insert the
+                        * last item on the list in order to help do batching
+                        * we need to not free the extent op until we actually
+                        * insert the extent_item
+                        */
+                       if (op->del == 2) {
+                               unlock_extent(&info->extent_ins, op->bytenr,
+                                             op->bytenr + op->num_bytes - 1,
+                                             GFP_NOFS);
+                               cur = cur->next;
+                               list_del_init(&op->list);
+                               kfree(op);
+                               if (cur != insert_list)
+                                       op = list_entry(cur,
+                                               struct pending_extent_op,
+                                               list);
+                       }
+               }
+               btrfs_mark_buffer_dirty(leaf);
+               btrfs_release_path(extent_root, path);
+
+               /*
+                * Ok backref's and items usually go right next to eachother,
+                * but if we could only insert 1 item that means that we
+                * inserted on the end of a leaf, and we have no idea what may
+                * be on the next leaf so we just play it safe.  In order to
+                * try and help this case we insert the last thing on our
+                * insert list so hopefully it will end up being the last
+                * thing on the leaf and everything else will be before it,
+                * which will let us insert a whole bunch of items at the same
+                * time.
+                */
+               if (ret == 1 && !last && (i + ret < total)) {
+                       /*
+                        * last: where we will pick up the next time around
+                        * i: our current key to insert, will be total - 1
+                        * cur: the current op we are screwing with
+                        * op: duh
+                        */
+                       last = i + ret;
+                       i = total - 1;
+                       cur = insert_list->prev;
+                       op = list_entry(cur, struct pending_extent_op, list);
+               } else if (last) {
+                       /*
+                        * ok we successfully inserted the last item on the
+                        * list, lets reset everything
+                        *
+                        * i: our current key to insert, so where we left off
+                        *    last time
+                        * last: done with this
+                        * cur: the op we are messing with
+                        * op: duh
+                        * total: since we inserted the last key, we need to
+                        *        decrement total so we dont overflow
+                        */
+                       i = last;
+                       last = 0;
+                       total--;
+                       if (i < total) {
+                               cur = insert_list->next;
+                               op = list_entry(cur, struct pending_extent_op,
+                                               list);
+                       }
+               } else {
+                       i += ret;
+               }
+
+               cond_resched();
+       }
+       ret = 0;
+       kfree(keys);
+       kfree(data_size);
+       return ret;
+}
+
+static noinline int insert_extent_backref(struct btrfs_trans_handle *trans,
                                          struct btrfs_root *root,
                                          struct btrfs_path *path,
                                          u64 bytenr, u64 parent,
@@ -618,7 +841,7 @@ out:
        return ret;
 }
 
-static int noinline remove_extent_backref(struct btrfs_trans_handle *trans,
+static noinline int remove_extent_backref(struct btrfs_trans_handle *trans,
                                          struct btrfs_root *root,
                                          struct btrfs_path *path)
 {
@@ -642,6 +865,291 @@ static int noinline remove_extent_backref(struct btrfs_trans_handle *trans,
        return ret;
 }
 
+#ifdef BIO_RW_DISCARD
+static void btrfs_issue_discard(struct block_device *bdev,
+                               u64 start, u64 len)
+{
+       blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL);
+}
+#endif
+
+static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
+                               u64 num_bytes)
+{
+#ifdef BIO_RW_DISCARD
+       int ret;
+       u64 map_length = num_bytes;
+       struct btrfs_multi_bio *multi = NULL;
+
+       /* Tell the block device(s) that the sectors can be discarded */
+       ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
+                             bytenr, &map_length, &multi, 0);
+       if (!ret) {
+               struct btrfs_bio_stripe *stripe = multi->stripes;
+               int i;
+
+               if (map_length > num_bytes)
+                       map_length = num_bytes;
+
+               for (i = 0; i < multi->num_stripes; i++, stripe++) {
+                       btrfs_issue_discard(stripe->dev->bdev,
+                                           stripe->physical,
+                                           map_length);
+               }
+               kfree(multi);
+       }
+
+       return ret;
+#else
+       return 0;
+#endif
+}
+
+static noinline int free_extents(struct btrfs_trans_handle *trans,
+                                struct btrfs_root *extent_root,
+                                struct list_head *del_list)
+{
+       struct btrfs_fs_info *info = extent_root->fs_info;
+       struct btrfs_path *path;
+       struct btrfs_key key, found_key;
+       struct extent_buffer *leaf;
+       struct list_head *cur;
+       struct pending_extent_op *op;
+       struct btrfs_extent_item *ei;
+       int ret, num_to_del, extent_slot = 0, found_extent = 0;
+       u32 refs;
+       u64 bytes_freed = 0;
+
+       path = btrfs_alloc_path();
+       if (!path)
+               return -ENOMEM;
+       path->reada = 1;
+
+search:
+       /* search for the backref for the current ref we want to delete */
+       cur = del_list->next;
+       op = list_entry(cur, struct pending_extent_op, list);
+       ret = lookup_extent_backref(trans, extent_root, path, op->bytenr,
+                                   op->orig_parent,
+                                   extent_root->root_key.objectid,
+                                   op->orig_generation, op->level, 1);
+       if (ret) {
+               printk(KERN_ERR "btrfs unable to find backref byte nr %llu "
+                      "root %llu gen %llu owner %u\n",
+                      (unsigned long long)op->bytenr,
+                      (unsigned long long)extent_root->root_key.objectid,
+                      (unsigned long long)op->orig_generation, op->level);
+               btrfs_print_leaf(extent_root, path->nodes[0]);
+               WARN_ON(1);
+               goto out;
+       }
+
+       extent_slot = path->slots[0];
+       num_to_del = 1;
+       found_extent = 0;
+
+       /*
+        * if we aren't the first item on the leaf we can move back one and see
+        * if our ref is right next to our extent item
+        */
+       if (likely(extent_slot)) {
+               extent_slot--;
+               btrfs_item_key_to_cpu(path->nodes[0], &found_key,
+                                     extent_slot);
+               if (found_key.objectid == op->bytenr &&
+                   found_key.type == BTRFS_EXTENT_ITEM_KEY &&
+                   found_key.offset == op->num_bytes) {
+                       num_to_del++;
+                       found_extent = 1;
+               }
+       }
+
+       /*
+        * if we didn't find the extent we need to delete the backref and then
+        * search for the extent item key so we can update its ref count
+        */
+       if (!found_extent) {
+               key.objectid = op->bytenr;
+               key.type = BTRFS_EXTENT_ITEM_KEY;
+               key.offset = op->num_bytes;
+
+               ret = remove_extent_backref(trans, extent_root, path);
+               BUG_ON(ret);
+               btrfs_release_path(extent_root, path);
+               ret = btrfs_search_slot(trans, extent_root, &key, path, -1, 1);
+               BUG_ON(ret);
+               extent_slot = path->slots[0];
+       }
+
+       /* this is where we update the ref count for the extent */
+       leaf = path->nodes[0];
+       ei = btrfs_item_ptr(leaf, extent_slot, struct btrfs_extent_item);
+       refs = btrfs_extent_refs(leaf, ei);
+       BUG_ON(refs == 0);
+       refs--;
+       btrfs_set_extent_refs(leaf, ei, refs);
+
+       btrfs_mark_buffer_dirty(leaf);
+
+       /*
+        * This extent needs deleting.  The reason cur_slot is extent_slot +
+        * num_to_del is because extent_slot points to the slot where the extent
+        * is, and if the backref was not right next to the extent we will be
+        * deleting at least 1 item, and will want to start searching at the
+        * slot directly next to extent_slot.  However if we did find the
+        * backref next to the extent item them we will be deleting at least 2
+        * items and will want to start searching directly after the ref slot
+        */
+       if (!refs) {
+               struct list_head *pos, *n, *end;
+               int cur_slot = extent_slot+num_to_del;
+               u64 super_used;
+               u64 root_used;
+
+               path->slots[0] = extent_slot;
+               bytes_freed = op->num_bytes;
+
+               mutex_lock(&info->pinned_mutex);
+               ret = pin_down_bytes(trans, extent_root, op->bytenr,
+                                    op->num_bytes, op->level >=
+                                    BTRFS_FIRST_FREE_OBJECTID);
+               mutex_unlock(&info->pinned_mutex);
+               BUG_ON(ret < 0);
+               op->del = ret;
+
+               /*
+                * we need to see if we can delete multiple things at once, so
+                * start looping through the list of extents we are wanting to
+                * delete and see if their extent/backref's are right next to
+                * eachother and the extents only have 1 ref
+                */
+               for (pos = cur->next; pos != del_list; pos = pos->next) {
+                       struct pending_extent_op *tmp;
+
+                       tmp = list_entry(pos, struct pending_extent_op, list);
+
+                       /* we only want to delete extent+ref at this stage */
+                       if (cur_slot >= btrfs_header_nritems(leaf) - 1)
+                               break;
+
+                       btrfs_item_key_to_cpu(leaf, &found_key, cur_slot);
+                       if (found_key.objectid != tmp->bytenr ||
+                           found_key.type != BTRFS_EXTENT_ITEM_KEY ||
+                           found_key.offset != tmp->num_bytes)
+                               break;
+
+                       /* check to make sure this extent only has one ref */
+                       ei = btrfs_item_ptr(leaf, cur_slot,
+                                           struct btrfs_extent_item);
+                       if (btrfs_extent_refs(leaf, ei) != 1)
+                               break;
+
+                       btrfs_item_key_to_cpu(leaf, &found_key, cur_slot+1);
+                       if (found_key.objectid != tmp->bytenr ||
+                           found_key.type != BTRFS_EXTENT_REF_KEY ||
+                           found_key.offset != tmp->orig_parent)
+                               break;
+
+                       /*
+                        * the ref is right next to the extent, we can set the
+                        * ref count to 0 since we will delete them both now
+                        */
+                       btrfs_set_extent_refs(leaf, ei, 0);
+
+                       /* pin down the bytes for this extent */
+                       mutex_lock(&info->pinned_mutex);
+                       ret = pin_down_bytes(trans, extent_root, tmp->bytenr,
+                                            tmp->num_bytes, tmp->level >=
+                                            BTRFS_FIRST_FREE_OBJECTID);
+                       mutex_unlock(&info->pinned_mutex);
+                       BUG_ON(ret < 0);
+
+                       /*
+                        * use the del field to tell if we need to go ahead and
+                        * free up the extent when we delete the item or not.
+                        */
+                       tmp->del = ret;
+                       bytes_freed += tmp->num_bytes;
+
+                       num_to_del += 2;
+                       cur_slot += 2;
+               }
+               end = pos;
+
+               /* update the free space counters */
+               spin_lock(&info->delalloc_lock);
+               super_used = btrfs_super_bytes_used(&info->super_copy);
+               btrfs_set_super_bytes_used(&info->super_copy,
+                                          super_used - bytes_freed);
+
+               root_used = btrfs_root_used(&extent_root->root_item);
+               btrfs_set_root_used(&extent_root->root_item,
+                                   root_used - bytes_freed);
+               spin_unlock(&info->delalloc_lock);
+
+               /* delete the items */
+               ret = btrfs_del_items(trans, extent_root, path,
+                                     path->slots[0], num_to_del);
+               BUG_ON(ret);
+
+               /*
+                * loop through the extents we deleted and do the cleanup work
+                * on them
+                */
+               for (pos = cur, n = pos->next; pos != end;
+                    pos = n, n = pos->next) {
+                       struct pending_extent_op *tmp;
+                       tmp = list_entry(pos, struct pending_extent_op, list);
+
+                       /*
+                        * remember tmp->del tells us wether or not we pinned
+                        * down the extent
+                        */
+                       ret = update_block_group(trans, extent_root,
+                                                tmp->bytenr, tmp->num_bytes, 0,
+                                                tmp->del);
+                       BUG_ON(ret);
+
+                       list_del_init(&tmp->list);
+                       unlock_extent(&info->extent_ins, tmp->bytenr,
+                                     tmp->bytenr + tmp->num_bytes - 1,
+                                     GFP_NOFS);
+                       kfree(tmp);
+               }
+       } else if (refs && found_extent) {
+               /*
+                * the ref and extent were right next to eachother, but the
+                * extent still has a ref, so just free the backref and keep
+                * going
+                */
+               ret = remove_extent_backref(trans, extent_root, path);
+               BUG_ON(ret);
+
+               list_del_init(&op->list);
+               unlock_extent(&info->extent_ins, op->bytenr,
+                             op->bytenr + op->num_bytes - 1, GFP_NOFS);
+               kfree(op);
+       } else {
+               /*
+                * the extent has multiple refs and the backref we were looking
+                * for was not right next to it, so just unlock and go next,
+                * we're good to go
+                */
+               list_del_init(&op->list);
+               unlock_extent(&info->extent_ins, op->bytenr,
+                             op->bytenr + op->num_bytes - 1, GFP_NOFS);
+               kfree(op);
+       }
+
+       btrfs_release_path(extent_root, path);
+       if (!list_empty(del_list))
+               goto search;
+
+out:
+       btrfs_free_path(path);
+       return ret;
+}
+
 static int __btrfs_update_extent_ref(struct btrfs_trans_handle *trans,
                                     struct btrfs_root *root, u64 bytenr,
                                     u64 orig_parent, u64 parent,
@@ -685,6 +1193,8 @@ static int __btrfs_update_extent_ref(struct btrfs_trans_handle *trans,
                        extent_op->generation = ref_generation;
                        extent_op->orig_generation = orig_generation;
                        extent_op->level = (int)owner_objectid;
+                       INIT_LIST_HEAD(&extent_op->list);
+                       extent_op->del = 0;
 
                        set_extent_bits(&root->fs_info->extent_ins,
                                        bytenr, bytenr + num_bytes - 1,
@@ -770,7 +1280,9 @@ static int __btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
        btrfs_item_key_to_cpu(l, &key, path->slots[0]);
        if (key.objectid != bytenr) {
                btrfs_print_leaf(root->fs_info->extent_root, path->nodes[0]);
-               printk("wanted %Lu found %Lu\n", bytenr, key.objectid);
+               printk(KERN_ERR "btrfs wanted %llu found %llu\n",
+                      (unsigned long long)bytenr,
+                      (unsigned long long)key.objectid);
                BUG();
        }
        BUG_ON(key.type != BTRFS_EXTENT_ITEM_KEY);
@@ -841,7 +1353,8 @@ int btrfs_lookup_extent_ref(struct btrfs_trans_handle *trans,
                goto out;
        if (ret != 0) {
                btrfs_print_leaf(root, path->nodes[0]);
-               printk("failed to find block number %Lu\n", bytenr);
+               printk(KERN_INFO "btrfs failed to find block number %llu\n",
+                      (unsigned long long)bytenr);
                BUG();
        }
        l = path->nodes[0];
@@ -853,7 +1366,7 @@ out:
 }
 
 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
-                         struct btrfs_root *root, u64 bytenr)
+                         struct btrfs_root *root, u64 objectid, u64 bytenr)
 {
        struct btrfs_root *extent_root = root->fs_info->extent_root;
        struct btrfs_path *path;
@@ -912,8 +1425,9 @@ int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
                ref_item = btrfs_item_ptr(leaf, path->slots[0],
                                          struct btrfs_extent_ref);
                ref_root = btrfs_ref_root(leaf, ref_item);
-               if (ref_root != root->root_key.objectid &&
-                   ref_root != BTRFS_TREE_LOG_OBJECTID) {
+               if ((ref_root != root->root_key.objectid &&
+                    ref_root != BTRFS_TREE_LOG_OBJECTID) ||
+                    objectid != btrfs_ref_objectid(leaf, ref_item)) {
                        ret = 1;
                        goto out;
                }
@@ -1225,7 +1739,7 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
        if (!path)
                return -ENOMEM;
 
-       while(1) {
+       while (1) {
                cache = NULL;
                spin_lock(&root->fs_info->block_group_cache_lock);
                for (n = rb_first(&root->fs_info->block_group_cache_tree);
@@ -1261,6 +1775,19 @@ int btrfs_write_dirty_block_groups(struct btrfs_trans_handle *trans,
        return werr;
 }
 
+int btrfs_extent_readonly(struct btrfs_root *root, u64 bytenr)
+{
+       struct btrfs_block_group_cache *block_group;
+       int readonly = 0;
+
+       block_group = btrfs_lookup_block_group(root->fs_info, bytenr);
+       if (!block_group || block_group->ro)
+               readonly = 1;
+       if (block_group)
+               put_block_group(block_group);
+       return readonly;
+}
+
 static int update_space_info(struct btrfs_fs_info *info, u64 flags,
                             u64 total_bytes, u64 bytes_used,
                             struct btrfs_space_info **space_info)
@@ -1277,7 +1804,7 @@ static int update_space_info(struct btrfs_fs_info *info, u64 flags,
                *space_info = found;
                return 0;
        }
-       found = kmalloc(sizeof(*found), GFP_NOFS);
+       found = kzalloc(sizeof(*found), GFP_NOFS);
        if (!found)
                return -ENOMEM;
 
@@ -1290,6 +1817,7 @@ static int update_space_info(struct btrfs_fs_info *info, u64 flags,
        found->bytes_used = bytes_used;
        found->bytes_pinned = 0;
        found->bytes_reserved = 0;
+       found->bytes_readonly = 0;
        found->full = 0;
        found->force_alloc = 0;
        *space_info = found;
@@ -1312,9 +1840,22 @@ static void set_avail_alloc_bits(struct btrfs_fs_info *fs_info, u64 flags)
        }
 }
 
-static u64 reduce_alloc_profile(struct btrfs_root *root, u64 flags)
+static void set_block_group_readonly(struct btrfs_block_group_cache *cache)
+{
+       spin_lock(&cache->space_info->lock);
+       spin_lock(&cache->lock);
+       if (!cache->ro) {
+               cache->space_info->bytes_readonly += cache->key.offset -
+                                       btrfs_block_group_used(&cache->item);
+               cache->ro = 1;
+       }
+       spin_unlock(&cache->lock);
+       spin_unlock(&cache->space_info->lock);
+}
+
+u64 btrfs_reduce_alloc_profile(struct btrfs_root *root, u64 flags)
 {
-       u64 num_devices = root->fs_info->fs_devices->num_devices;
+       u64 num_devices = root->fs_info->fs_devices->rw_devices;
 
        if (num_devices == 1)
                flags &= ~(BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID0);
@@ -1346,11 +1887,11 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
 {
        struct btrfs_space_info *space_info;
        u64 thresh;
-       u64 start;
-       u64 num_bytes;
-       int ret = 0, waited = 0;
+       int ret = 0;
+
+       mutex_lock(&extent_root->fs_info->chunk_mutex);
 
-       flags = reduce_alloc_profile(extent_root, flags);
+       flags = btrfs_reduce_alloc_profile(extent_root, flags);
 
        space_info = __find_space_info(extent_root->fs_info, flags);
        if (!space_info) {
@@ -1370,46 +1911,21 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
                goto out;
        }
 
-       thresh = div_factor(space_info->total_bytes, 6);
+       thresh = space_info->total_bytes - space_info->bytes_readonly;
+       thresh = div_factor(thresh, 6);
        if (!force &&
           (space_info->bytes_used + space_info->bytes_pinned +
            space_info->bytes_reserved + alloc_bytes) < thresh) {
                spin_unlock(&space_info->lock);
                goto out;
        }
-
        spin_unlock(&space_info->lock);
 
-       ret = mutex_trylock(&extent_root->fs_info->chunk_mutex);
-       if (!ret && !force) {
-               goto out;
-       } else if (!ret) {
-               mutex_lock(&extent_root->fs_info->chunk_mutex);
-               waited = 1;
-       }
-
-       if (waited) {
-               spin_lock(&space_info->lock);
-               if (space_info->full) {
-                       spin_unlock(&space_info->lock);
-                       goto out_unlock;
-               }
-               spin_unlock(&space_info->lock);
-       }
-
-       ret = btrfs_alloc_chunk(trans, extent_root, &start, &num_bytes, flags);
-       if (ret) {
-printk("space info full %Lu\n", flags);
+       ret = btrfs_alloc_chunk(trans, extent_root, flags);
+       if (ret)
                space_info->full = 1;
-               goto out_unlock;
-       }
-
-       ret = btrfs_make_block_group(trans, extent_root, 0, flags,
-                    BTRFS_FIRST_CHUNK_TREE_OBJECTID, start, num_bytes);
-       BUG_ON(ret);
-out_unlock:
-       mutex_unlock(&extent_root->fs_info->chunk_mutex);
 out:
+       mutex_unlock(&extent_root->fs_info->chunk_mutex);
        return ret;
 }
 
@@ -1424,11 +1940,10 @@ static int update_block_group(struct btrfs_trans_handle *trans,
        u64 old_val;
        u64 byte_in_group;
 
-       while(total) {
+       while (total) {
                cache = btrfs_lookup_block_group(info, bytenr);
-               if (!cache) {
+               if (!cache)
                        return -1;
-               }
                byte_in_group = bytenr - cache->key.objectid;
                WARN_ON(byte_in_group > cache->key.offset);
 
@@ -1440,23 +1955,32 @@ static int update_block_group(struct btrfs_trans_handle *trans,
                if (alloc) {
                        old_val += num_bytes;
                        cache->space_info->bytes_used += num_bytes;
+                       if (cache->ro)
+                               cache->space_info->bytes_readonly -= num_bytes;
                        btrfs_set_block_group_used(&cache->item, old_val);
                        spin_unlock(&cache->lock);
                        spin_unlock(&cache->space_info->lock);
                } else {
                        old_val -= num_bytes;
                        cache->space_info->bytes_used -= num_bytes;
+                       if (cache->ro)
+                               cache->space_info->bytes_readonly += num_bytes;
                        btrfs_set_block_group_used(&cache->item, old_val);
                        spin_unlock(&cache->lock);
                        spin_unlock(&cache->space_info->lock);
                        if (mark_free) {
                                int ret;
+
+                               ret = btrfs_discard_extent(root, bytenr,
+                                                          num_bytes);
+                               WARN_ON(ret);
+
                                ret = btrfs_add_free_space(cache, bytenr,
                                                           num_bytes);
-                               if (ret)
-                                       return -1;
+                               WARN_ON(ret);
                        }
                }
+               put_block_group(cache);
                total -= num_bytes;
                bytenr += num_bytes;
        }
@@ -1466,12 +1990,16 @@ static int update_block_group(struct btrfs_trans_handle *trans,
 static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
 {
        struct btrfs_block_group_cache *cache;
+       u64 bytenr;
 
        cache = btrfs_lookup_first_block_group(root->fs_info, search_start);
        if (!cache)
                return 0;
 
-       return cache->key.objectid;
+       bytenr = cache->key.objectid;
+       put_block_group(cache);
+
+       return bytenr;
 }
 
 int btrfs_update_pinned_extents(struct btrfs_root *root,
@@ -1510,7 +2038,10 @@ int btrfs_update_pinned_extents(struct btrfs_root *root,
                        spin_unlock(&cache->lock);
                        spin_unlock(&cache->space_info->lock);
                        fs_info->total_pinned -= len;
+                       if (cache->cached)
+                               btrfs_add_free_space(cache, bytenr, len);
                }
+               put_block_group(cache);
                bytenr += len;
                num -= len;
        }
@@ -1541,6 +2072,7 @@ static int update_reserved_extents(struct btrfs_root *root,
                }
                spin_unlock(&cache->lock);
                spin_unlock(&cache->space_info->lock);
+               put_block_group(cache);
                bytenr += len;
                num -= len;
        }
@@ -1556,7 +2088,7 @@ int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy)
        int ret;
 
        mutex_lock(&root->fs_info->pinned_mutex);
-       while(1) {
+       while (1) {
                ret = find_first_extent_bit(pinned_extents, last,
                                            &start, &end, EXTENT_DIRTY);
                if (ret)
@@ -1575,19 +2107,19 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
        u64 start;
        u64 end;
        int ret;
-       struct btrfs_block_group_cache *cache;
 
        mutex_lock(&root->fs_info->pinned_mutex);
-       while(1) {
+       while (1) {
                ret = find_first_extent_bit(unpin, 0, &start, &end,
                                            EXTENT_DIRTY);
                if (ret)
                        break;
+
+               ret = btrfs_discard_extent(root, start, end + 1 - start);
+
                btrfs_update_pinned_extents(root, start, end + 1 - start, 0);
                clear_extent_dirty(unpin, start, end, GFP_NOFS);
-               cache = btrfs_lookup_block_group(root->fs_info, start);
-               if (cache->cached)
-                       btrfs_add_free_space(cache, start, end - start + 1);
+
                if (need_resched()) {
                        mutex_unlock(&root->fs_info->pinned_mutex);
                        cond_resched();
@@ -1595,7 +2127,7 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
                }
        }
        mutex_unlock(&root->fs_info->pinned_mutex);
-       return 0;
+       return ret;
 }
 
 static int finish_current_insert(struct btrfs_trans_handle *trans,
@@ -1605,102 +2137,187 @@ static int finish_current_insert(struct btrfs_trans_handle *trans,
        u64 end;
        u64 priv;
        u64 search = 0;
+       u64 skipped = 0;
        struct btrfs_fs_info *info = extent_root->fs_info;
        struct btrfs_path *path;
-       struct btrfs_extent_ref *ref;
-       struct pending_extent_op *extent_op;
-       struct btrfs_key key;
-       struct btrfs_extent_item extent_item;
+       struct pending_extent_op *extent_op, *tmp;
+       struct list_head insert_list, update_list;
        int ret;
-       int err = 0;
+       int num_inserts = 0, max_inserts;
 
-       btrfs_set_stack_extent_refs(&extent_item, 1);
        path = btrfs_alloc_path();
+       INIT_LIST_HEAD(&insert_list);
+       INIT_LIST_HEAD(&update_list);
 
-       while(1) {
-               mutex_lock(&info->extent_ins_mutex);
+       max_inserts = extent_root->leafsize /
+               (2 * sizeof(struct btrfs_key) + 2 * sizeof(struct btrfs_item) +
+                sizeof(struct btrfs_extent_ref) +
+                sizeof(struct btrfs_extent_item));
+again:
+       mutex_lock(&info->extent_ins_mutex);
+       while (1) {
                ret = find_first_extent_bit(&info->extent_ins, search, &start,
                                            &end, EXTENT_WRITEBACK);
                if (ret) {
-                       mutex_unlock(&info->extent_ins_mutex);
-                       if (search && all) {
+                       if (skipped && all && !num_inserts) {
+                               skipped = 0;
                                search = 0;
                                continue;
                        }
+                       mutex_unlock(&info->extent_ins_mutex);
                        break;
                }
 
                ret = try_lock_extent(&info->extent_ins, start, end, GFP_NOFS);
                if (!ret) {
+                       skipped = 1;
                        search = end + 1;
-                       mutex_unlock(&info->extent_ins_mutex);
-                       cond_resched();
+                       if (need_resched()) {
+                               mutex_unlock(&info->extent_ins_mutex);
+                               cond_resched();
+                               mutex_lock(&info->extent_ins_mutex);
+                       }
                        continue;
                }
-               BUG_ON(ret < 0);
 
                ret = get_state_private(&info->extent_ins, start, &priv);
                BUG_ON(ret);
-               extent_op = (struct pending_extent_op *)(unsigned long)priv;
-
-               mutex_unlock(&info->extent_ins_mutex);
+               extent_op = (struct pending_extent_op *)(unsigned long) priv;
 
                if (extent_op->type == PENDING_EXTENT_INSERT) {
-                       key.objectid = start;
-                       key.offset = end + 1 - start;
-                       key.type = BTRFS_EXTENT_ITEM_KEY;
-                       err = btrfs_insert_item(trans, extent_root, &key,
-                                       &extent_item, sizeof(extent_item));
-                       BUG_ON(err);
+                       num_inserts++;
+                       list_add_tail(&extent_op->list, &insert_list);
+                       search = end + 1;
+                       if (num_inserts == max_inserts) {
+                               mutex_unlock(&info->extent_ins_mutex);
+                               break;
+                       }
+               } else if (extent_op->type == PENDING_BACKREF_UPDATE) {
+                       list_add_tail(&extent_op->list, &update_list);
+                       search = end + 1;
+               } else {
+                       BUG();
+               }
+       }
 
-                       mutex_lock(&info->extent_ins_mutex);
-                       clear_extent_bits(&info->extent_ins, start, end,
-                                         EXTENT_WRITEBACK, GFP_NOFS);
-                       mutex_unlock(&info->extent_ins_mutex);
+       /*
+        * process the update list, clear the writeback bit for it, and if
+        * somebody marked this thing for deletion then just unlock it and be
+        * done, the free_extents will handle it
+        */
+       mutex_lock(&info->extent_ins_mutex);
+       list_for_each_entry_safe(extent_op, tmp, &update_list, list) {
+               clear_extent_bits(&info->extent_ins, extent_op->bytenr,
+                                 extent_op->bytenr + extent_op->num_bytes - 1,
+                                 EXTENT_WRITEBACK, GFP_NOFS);
+               if (extent_op->del) {
+                       list_del_init(&extent_op->list);
+                       unlock_extent(&info->extent_ins, extent_op->bytenr,
+                                     extent_op->bytenr + extent_op->num_bytes
+                                     - 1, GFP_NOFS);
+                       kfree(extent_op);
+               }
+       }
+       mutex_unlock(&info->extent_ins_mutex);
 
-                       err = insert_extent_backref(trans, extent_root, path,
-                                               start, extent_op->parent,
-                                               extent_root->root_key.objectid,
-                                               extent_op->generation,
-                                               extent_op->level);
-                       BUG_ON(err);
-               } else if (extent_op->type == PENDING_BACKREF_UPDATE) {
-                       err = lookup_extent_backref(trans, extent_root, path,
-                                               start, extent_op->orig_parent,
-                                               extent_root->root_key.objectid,
-                                               extent_op->orig_generation,
-                                               extent_op->level, 0);
-                       BUG_ON(err);
+       /*
+        * still have things left on the update list, go ahead an update
+        * everything
+        */
+       if (!list_empty(&update_list)) {
+               ret = update_backrefs(trans, extent_root, path, &update_list);
+               BUG_ON(ret);
+       }
 
-                       mutex_lock(&info->extent_ins_mutex);
-                       clear_extent_bits(&info->extent_ins, start, end,
-                                         EXTENT_WRITEBACK, GFP_NOFS);
-                       mutex_unlock(&info->extent_ins_mutex);
+       /*
+        * if no inserts need to be done, but we skipped some extents and we
+        * need to make sure everything is cleaned then reset everything and
+        * go back to the beginning
+        */
+       if (!num_inserts && all && skipped) {
+               search = 0;
+               skipped = 0;
+               INIT_LIST_HEAD(&update_list);
+               INIT_LIST_HEAD(&insert_list);
+               goto again;
+       } else if (!num_inserts) {
+               goto out;
+       }
 
-                       key.objectid = start;
-                       key.offset = extent_op->parent;
-                       key.type = BTRFS_EXTENT_REF_KEY;
-                       err = btrfs_set_item_key_safe(trans, extent_root, path,
-                                                     &key);
-                       BUG_ON(err);
-                       ref = btrfs_item_ptr(path->nodes[0], path->slots[0],
-                                            struct btrfs_extent_ref);
-                       btrfs_set_ref_generation(path->nodes[0], ref,
-                                                extent_op->generation);
-                       btrfs_mark_buffer_dirty(path->nodes[0]);
-                       btrfs_release_path(extent_root, path);
-               } else {
-                       BUG_ON(1);
+       /*
+        * process the insert extents list.  Again if we are deleting this
+        * extent, then just unlock it, pin down the bytes if need be, and be
+        * done with it.  Saves us from having to actually insert the extent
+        * into the tree and then subsequently come along and delete it
+        */
+       mutex_lock(&info->extent_ins_mutex);
+       list_for_each_entry_safe(extent_op, tmp, &insert_list, list) {
+               clear_extent_bits(&info->extent_ins, extent_op->bytenr,
+                                 extent_op->bytenr + extent_op->num_bytes - 1,
+                                 EXTENT_WRITEBACK, GFP_NOFS);
+               if (extent_op->del) {
+                       u64 used;
+                       list_del_init(&extent_op->list);
+                       unlock_extent(&info->extent_ins, extent_op->bytenr,
+                                     extent_op->bytenr + extent_op->num_bytes
+                                     - 1, GFP_NOFS);
+
+                       mutex_lock(&extent_root->fs_info->pinned_mutex);
+                       ret = pin_down_bytes(trans, extent_root,
+                                            extent_op->bytenr,
+                                            extent_op->num_bytes, 0);
+                       mutex_unlock(&extent_root->fs_info->pinned_mutex);
+
+                       spin_lock(&info->delalloc_lock);
+                       used = btrfs_super_bytes_used(&info->super_copy);
+                       btrfs_set_super_bytes_used(&info->super_copy,
+                                       used - extent_op->num_bytes);
+                       used = btrfs_root_used(&extent_root->root_item);
+                       btrfs_set_root_used(&extent_root->root_item,
+                                       used - extent_op->num_bytes);
+                       spin_unlock(&info->delalloc_lock);
+
+                       ret = update_block_group(trans, extent_root,
+                                                extent_op->bytenr,
+                                                extent_op->num_bytes,
+                                                0, ret > 0);
+                       BUG_ON(ret);
+                       kfree(extent_op);
+                       num_inserts--;
                }
-               kfree(extent_op);
-               unlock_extent(&info->extent_ins, start, end, GFP_NOFS);
-               if (all)
-                       search = 0;
-               else
-                       search = end + 1;
+       }
+       mutex_unlock(&info->extent_ins_mutex);
 
-               cond_resched();
+       ret = insert_extents(trans, extent_root, path, &insert_list,
+                            num_inserts);
+       BUG_ON(ret);
+
+       /*
+        * if we broke out of the loop in order to insert stuff because we hit
+        * the maximum number of inserts at a time we can handle, then loop
+        * back and pick up where we left off
+        */
+       if (num_inserts == max_inserts) {
+               INIT_LIST_HEAD(&insert_list);
+               INIT_LIST_HEAD(&update_list);
+               num_inserts = 0;
+               goto again;
+       }
+
+       /*
+        * again, if we need to make absolutely sure there are no more pending
+        * extent operations left and we know that we skipped some, go back to
+        * the beginning and do it all again
+        */
+       if (all && skipped) {
+               INIT_LIST_HEAD(&insert_list);
+               INIT_LIST_HEAD(&update_list);
+               search = 0;
+               skipped = 0;
+               num_inserts = 0;
+               goto again;
        }
+out:
        btrfs_free_path(path);
        return 0;
 }
@@ -1782,7 +2399,7 @@ static int __free_extent(struct btrfs_trans_handle *trans,
        if (ret == 0) {
                struct btrfs_key found_key;
                extent_slot = path->slots[0];
-               while(extent_slot > 0) {
+               while (extent_slot > 0) {
                        extent_slot--;
                        btrfs_item_key_to_cpu(path->nodes[0], &found_key,
                                              extent_slot);
@@ -1802,15 +2419,24 @@ static int __free_extent(struct btrfs_trans_handle *trans,
                        btrfs_release_path(extent_root, path);
                        ret = btrfs_search_slot(trans, extent_root,
                                                &key, path, -1, 1);
+                       if (ret) {
+                               printk(KERN_ERR "umm, got %d back from search"
+                                      ", was looking for %llu\n", ret,
+                                      (unsigned long long)bytenr);
+                               btrfs_print_leaf(extent_root, path->nodes[0]);
+                       }
                        BUG_ON(ret);
                        extent_slot = path->slots[0];
                }
        } else {
                btrfs_print_leaf(extent_root, path->nodes[0]);
                WARN_ON(1);
-               printk("Unable to find ref byte nr %Lu root %Lu "
-                      "gen %Lu owner %Lu\n", bytenr,
-                      root_objectid, ref_generation, owner_objectid);
+               printk(KERN_ERR "btrfs unable to find ref byte nr %llu "
+                      "root %llu gen %llu owner %llu\n",
+                      (unsigned long long)bytenr,
+                      (unsigned long long)root_objectid,
+                      (unsigned long long)ref_generation,
+                      (unsigned long long)owner_objectid);
        }
 
        leaf = path->nodes[0];
@@ -1849,10 +2475,6 @@ static int __free_extent(struct btrfs_trans_handle *trans,
        if (refs == 0) {
                u64 super_used;
                u64 root_used;
-#ifdef BIO_RW_DISCARD
-               u64 map_length = num_bytes;
-               struct btrfs_multi_bio *multi = NULL;
-#endif
 
                if (pin) {
                        mutex_lock(&root->fs_info->pinned_mutex);
@@ -1863,45 +2485,30 @@ static int __free_extent(struct btrfs_trans_handle *trans,
                                mark_free = 1;
                        BUG_ON(ret < 0);
                }
-
                /* block accounting for super block */
-               spin_lock_irq(&info->delalloc_lock);
+               spin_lock(&info->delalloc_lock);
                super_used = btrfs_super_bytes_used(&info->super_copy);
                btrfs_set_super_bytes_used(&info->super_copy,
                                           super_used - num_bytes);
-               spin_unlock_irq(&info->delalloc_lock);
 
                /* block accounting for root item */
                root_used = btrfs_root_used(&root->root_item);
                btrfs_set_root_used(&root->root_item,
                                           root_used - num_bytes);
+               spin_unlock(&info->delalloc_lock);
                ret = btrfs_del_items(trans, extent_root, path, path->slots[0],
                                      num_to_del);
                BUG_ON(ret);
                btrfs_release_path(extent_root, path);
+
+               if (owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
+                       ret = btrfs_del_csums(trans, root, bytenr, num_bytes);
+                       BUG_ON(ret);
+               }
+
                ret = update_block_group(trans, root, bytenr, num_bytes, 0,
                                         mark_free);
                BUG_ON(ret);
-
-#ifdef BIO_RW_DISCARD
-               /* Tell the block device(s) that the sectors can be discarded */
-               ret = btrfs_map_block(&root->fs_info->mapping_tree, READ,
-                                     bytenr, &map_length, &multi, 0);
-               if (!ret) {
-                       struct btrfs_bio_stripe *stripe = multi->stripes;
-                       int i;
-
-                       if (map_length > num_bytes)
-                               map_length = num_bytes;
-
-                       for (i = 0; i < multi->num_stripes; i++, stripe++) {
-                               blkdev_issue_discard(stripe->dev->bdev,
-                                                    stripe->physical >> 9,
-                                                    map_length >> 9);
-                       }
-                       kfree(multi);
-               }
-#endif
        }
        btrfs_free_path(path);
        finish_current_insert(trans, extent_root, 0);
@@ -1912,8 +2519,8 @@ static int __free_extent(struct btrfs_trans_handle *trans,
  * find all the blocks marked as pending in the radix tree and remove
  * them from the extent map
  */
-static int del_pending_extents(struct btrfs_trans_handle *trans, struct
-                              btrfs_root *extent_root, int all)
+static int del_pending_extents(struct btrfs_trans_handle *trans,
+                              struct btrfs_root *extent_root, int all)
 {
        int ret;
        int err = 0;
@@ -1921,32 +2528,42 @@ static int del_pending_extents(struct btrfs_trans_handle *trans, struct
        u64 end;
        u64 priv;
        u64 search = 0;
+       int nr = 0, skipped = 0;
        struct extent_io_tree *pending_del;
        struct extent_io_tree *extent_ins;
        struct pending_extent_op *extent_op;
        struct btrfs_fs_info *info = extent_root->fs_info;
+       struct list_head delete_list;
 
+       INIT_LIST_HEAD(&delete_list);
        extent_ins = &extent_root->fs_info->extent_ins;
        pending_del = &extent_root->fs_info->pending_del;
 
-       while(1) {
-               mutex_lock(&info->extent_ins_mutex);
+again:
+       mutex_lock(&info->extent_ins_mutex);
+       while (1) {
                ret = find_first_extent_bit(pending_del, search, &start, &end,
                                            EXTENT_WRITEBACK);
                if (ret) {
-                       mutex_unlock(&info->extent_ins_mutex);
-                       if (all && search) {
+                       if (all && skipped && !nr) {
                                search = 0;
                                continue;
                        }
+                       mutex_unlock(&info->extent_ins_mutex);
                        break;
                }
 
                ret = try_lock_extent(extent_ins, start, end, GFP_NOFS);
                if (!ret) {
                        search = end+1;
-                       mutex_unlock(&info->extent_ins_mutex);
-                       cond_resched();
+                       skipped = 1;
+
+                       if (need_resched()) {
+                               mutex_unlock(&info->extent_ins_mutex);
+                               cond_resched();
+                               mutex_lock(&info->extent_ins_mutex);
+                       }
+
                        continue;
                }
                BUG_ON(ret < 0);
@@ -1959,15 +2576,8 @@ static int del_pending_extents(struct btrfs_trans_handle *trans, struct
                                  GFP_NOFS);
                if (!test_range_bit(extent_ins, start, end,
                                    EXTENT_WRITEBACK, 0)) {
-                       mutex_unlock(&info->extent_ins_mutex);
-free_extent:
-                       ret = __free_extent(trans, extent_root,
-                                           start, end + 1 - start,
-                                           extent_op->orig_parent,
-                                           extent_root->root_key.objectid,
-                                           extent_op->orig_generation,
-                                           extent_op->level, 1, 0);
-                       kfree(extent_op);
+                       list_add_tail(&extent_op->list, &delete_list);
+                       nr++;
                } else {
                        kfree(extent_op);
 
@@ -1980,10 +2590,12 @@ free_extent:
                        clear_extent_bits(&info->extent_ins, start, end,
                                          EXTENT_WRITEBACK, GFP_NOFS);
 
-                       mutex_unlock(&info->extent_ins_mutex);
-
-                       if (extent_op->type == PENDING_BACKREF_UPDATE)
-                               goto free_extent;
+                       if (extent_op->type == PENDING_BACKREF_UPDATE) {
+                               list_add_tail(&extent_op->list, &delete_list);
+                               search = end + 1;
+                               nr++;
+                               continue;
+                       }
 
                        mutex_lock(&extent_root->fs_info->pinned_mutex);
                        ret = pin_down_bytes(trans, extent_root, start,
@@ -1993,19 +2605,34 @@ free_extent:
                        ret = update_block_group(trans, extent_root, start,
                                                end + 1 - start, 0, ret > 0);
 
+                       unlock_extent(extent_ins, start, end, GFP_NOFS);
                        BUG_ON(ret);
                        kfree(extent_op);
                }
                if (ret)
                        err = ret;
-               unlock_extent(extent_ins, start, end, GFP_NOFS);
 
-               if (all)
-                       search = 0;
-               else
-                       search = end + 1;
-               cond_resched();
+               search = end + 1;
+
+               if (need_resched()) {
+                       mutex_unlock(&info->extent_ins_mutex);
+                       cond_resched();
+                       mutex_lock(&info->extent_ins_mutex);
+               }
+       }
+
+       if (nr) {
+               ret = free_extents(trans, extent_root, &delete_list);
+               BUG_ON(ret);
+       }
+
+       if (all && skipped) {
+               INIT_LIST_HEAD(&delete_list);
+               search = 0;
+               nr = 0;
+               goto again;
        }
+
        return err;
 }
 
@@ -2024,7 +2651,29 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
 
        WARN_ON(num_bytes < root->sectorsize);
        if (root == extent_root) {
-               struct pending_extent_op *extent_op;
+               struct pending_extent_op *extent_op = NULL;
+
+               mutex_lock(&root->fs_info->extent_ins_mutex);
+               if (test_range_bit(&root->fs_info->extent_ins, bytenr,
+                               bytenr + num_bytes - 1, EXTENT_WRITEBACK, 0)) {
+                       u64 priv;
+                       ret = get_state_private(&root->fs_info->extent_ins,
+                                               bytenr, &priv);
+                       BUG_ON(ret);
+                       extent_op = (struct pending_extent_op *)
+                                               (unsigned long)priv;
+
+                       extent_op->del = 1;
+                       if (extent_op->type == PENDING_EXTENT_INSERT) {
+                               mutex_unlock(&root->fs_info->extent_ins_mutex);
+                               return 0;
+                       }
+               }
+
+               if (extent_op) {
+                       ref_generation = extent_op->orig_generation;
+                       parent = extent_op->orig_parent;
+               }
 
                extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
                BUG_ON(!extent_op);
@@ -2037,8 +2686,9 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
                extent_op->generation = ref_generation;
                extent_op->orig_generation = ref_generation;
                extent_op->level = (int)owner_objectid;
+               INIT_LIST_HEAD(&extent_op->list);
+               extent_op->del = 0;
 
-               mutex_lock(&root->fs_info->extent_ins_mutex);
                set_extent_bits(&root->fs_info->pending_del,
                                bytenr, bytenr + num_bytes - 1,
                                EXTENT_WRITEBACK, GFP_NOFS);
@@ -2056,6 +2706,7 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
                        cache = btrfs_lookup_block_group(root->fs_info, bytenr);
                        BUG_ON(!cache);
                        btrfs_add_free_space(cache, bytenr, num_bytes);
+                       put_block_group(cache);
                        update_reserved_extents(root, bytenr, num_bytes, 0);
                        return 0;
                }
@@ -2104,7 +2755,7 @@ static u64 stripe_align(struct btrfs_root *root, u64 val)
  * ins->offset == number of blocks
  * Any available blocks before search_start are skipped.
  */
-static int noinline find_free_extent(struct btrfs_trans_handle *trans,
+static noinline int find_free_extent(struct btrfs_trans_handle *trans,
                                     struct btrfs_root *orig_root,
                                     u64 num_bytes, u64 empty_size,
                                     u64 search_start, u64 search_end,
@@ -2113,7 +2764,7 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans,
                                     int data)
 {
        int ret = 0;
-       struct btrfs_root * root = orig_root->fs_info->extent_root;
+       struct btrfs_root *root = orig_root->fs_info->extent_root;
        u64 total_needed = num_bytes;
        u64 *last_ptr = NULL;
        u64 last_wanted = 0;
@@ -2123,6 +2774,7 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans,
        int allowed_chunk_alloc = 0;
        struct list_head *head = NULL, *cur = NULL;
        int loop = 0;
+       int extra_loop = 0;
        struct btrfs_space_info *space_info;
 
        WARN_ON(num_bytes < root->sectorsize);
@@ -2173,20 +2825,25 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans,
                 * group thats not of the proper type, while looping this
                 * should never happen
                 */
+               if (empty_size)
+                       extra_loop = 1;
+
                if (!block_group)
                        goto new_group_no_lock;
 
+               if (unlikely(!block_group->cached)) {
+                       mutex_lock(&block_group->cache_mutex);
+                       ret = cache_block_group(root, block_group);
+                       mutex_unlock(&block_group->cache_mutex);
+                       if (ret)
+                               break;
+               }
+
                mutex_lock(&block_group->alloc_mutex);
                if (unlikely(!block_group_bits(block_group, data)))
                        goto new_group;
 
-               ret = cache_block_group(root, block_group);
-               if (ret) {
-                       mutex_unlock(&block_group->alloc_mutex);
-                       break;
-               }
-
-               if (block_group->ro)
+               if (unlikely(block_group->ro))
                        goto new_group;
 
                free_space = btrfs_find_free_space(block_group, search_start,
@@ -2208,6 +2865,7 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans,
 
                        if (last_wanted && search_start != last_wanted) {
                                total_needed += empty_cluster;
+                               empty_size += empty_cluster;
                                last_wanted = 0;
                                /*
                                 * if search_start is still in this block group
@@ -2253,12 +2911,14 @@ static int noinline find_free_extent(struct btrfs_trans_handle *trans,
                }
 new_group:
                mutex_unlock(&block_group->alloc_mutex);
+               put_block_group(block_group);
+               block_group = NULL;
 new_group_no_lock:
+               /* don't try to compare new allocations against the
+                * last allocation any more
+                */
                last_wanted = 0;
-               if (!allowed_chunk_alloc) {
-                       total_needed -= empty_size;
-                       empty_size = 0;
-               }
+
                /*
                 * Here's how this works.
                 * loop == 0: we were searching a block group via a hint
@@ -2276,24 +2936,43 @@ new_group_no_lock:
                        cur = head->next;
                        loop++;
                } else if (loop == 1 && cur == head) {
-
+                       int keep_going;
+
+                       /* at this point we give up on the empty_size
+                        * allocations and just try to allocate the min
+                        * space.
+                        *
+                        * The extra_loop field was set if an empty_size
+                        * allocation was attempted above, and if this
+                        * is try we need to try the loop again without
+                        * the additional empty_size.
+                        */
                        total_needed -= empty_size;
                        empty_size = 0;
+                       keep_going = extra_loop;
+                       loop++;
 
                        if (allowed_chunk_alloc && !chunk_alloc_done) {
                                up_read(&space_info->groups_sem);
                                ret = do_chunk_alloc(trans, root, num_bytes +
                                                     2 * 1024 * 1024, data, 1);
-                               if (ret < 0)
-                                       break;
                                down_read(&space_info->groups_sem);
-                               loop++;
+                               if (ret < 0)
+                                       goto loop_check;
                                head = &space_info->block_groups;
-                               cur = head->next;
+                               /*
+                                * we've allocated a new chunk, keep
+                                * trying
+                                */
+                               keep_going = 1;
                                chunk_alloc_done = 1;
                        } else if (!allowed_chunk_alloc) {
                                space_info->force_alloc = 1;
-                               break;
+                       }
+loop_check:
+                       if (keep_going) {
+                               cur = head->next;
+                               extra_loop = 0;
                        } else {
                                break;
                        }
@@ -2303,6 +2982,8 @@ new_group_no_lock:
 
                block_group = list_entry(cur, struct btrfs_block_group_cache,
                                         list);
+               atomic_inc(&block_group->count);
+
                search_start = block_group->key.objectid;
                cur = cur->next;
        }
@@ -2310,14 +2991,21 @@ new_group_no_lock:
        /* we found what we needed */
        if (ins->objectid) {
                if (!(data & BTRFS_BLOCK_GROUP_DATA))
-                       trans->block_group = block_group;
+                       trans->block_group = block_group->key.objectid;
 
                if (last_ptr)
                        *last_ptr = ins->objectid + ins->offset;
                ret = 0;
        } else if (!ret) {
+               printk(KERN_ERR "btrfs searching for %llu bytes, "
+                      "num_bytes %llu, loop %d, allowed_alloc %d\n",
+                      (unsigned long long)total_needed,
+                      (unsigned long long)num_bytes,
+                      loop, allowed_chunk_alloc);
                ret = -ENOSPC;
        }
+       if (block_group)
+               put_block_group(block_group);
 
        up_read(&space_info->groups_sem);
        return ret;
@@ -2328,19 +3016,22 @@ static void dump_space_info(struct btrfs_space_info *info, u64 bytes)
        struct btrfs_block_group_cache *cache;
        struct list_head *l;
 
-       printk(KERN_INFO "space_info has %Lu free, is %sfull\n",
-              info->total_bytes - info->bytes_used - info->bytes_pinned -
-              info->bytes_reserved, (info->full) ? "" : "not ");
+       printk(KERN_INFO "space_info has %llu free, is %sfull\n",
+              (unsigned long long)(info->total_bytes - info->bytes_used -
+                                   info->bytes_pinned - info->bytes_reserved),
+              (info->full) ? "" : "not ");
 
        down_read(&info->groups_sem);
        list_for_each(l, &info->block_groups) {
                cache = list_entry(l, struct btrfs_block_group_cache, list);
                spin_lock(&cache->lock);
-               printk(KERN_INFO "block group %Lu has %Lu bytes, %Lu used "
-                      "%Lu pinned %Lu reserved\n",
-                      cache->key.objectid, cache->key.offset,
-                      btrfs_block_group_used(&cache->item),
-                      cache->pinned, cache->reserved);
+               printk(KERN_INFO "block group %llu has %llu bytes, %llu used "
+                      "%llu pinned %llu reserved\n",
+                      (unsigned long long)cache->key.objectid,
+                      (unsigned long long)cache->key.offset,
+                      (unsigned long long)btrfs_block_group_used(&cache->item),
+                      (unsigned long long)cache->pinned,
+                      (unsigned long long)cache->reserved);
                btrfs_dump_free_space(cache, bytes);
                spin_unlock(&cache->lock);
        }
@@ -2361,19 +3052,19 @@ static int __btrfs_reserve_extent(struct btrfs_trans_handle *trans,
 
        if (data) {
                alloc_profile = info->avail_data_alloc_bits &
-                               info->data_alloc_profile;
+                       info->data_alloc_profile;
                data = BTRFS_BLOCK_GROUP_DATA | alloc_profile;
        } else if (root == root->fs_info->chunk_root) {
                alloc_profile = info->avail_system_alloc_bits &
-                               info->system_alloc_profile;
+                       info->system_alloc_profile;
                data = BTRFS_BLOCK_GROUP_SYSTEM | alloc_profile;
        } else {
                alloc_profile = info->avail_metadata_alloc_bits &
-                               info->metadata_alloc_profile;
+                       info->metadata_alloc_profile;
                data = BTRFS_BLOCK_GROUP_METADATA | alloc_profile;
        }
 again:
-       data = reduce_alloc_profile(root, data);
+       data = btrfs_reduce_alloc_profile(root, data);
        /*
         * the only place that sets empty_size is btrfs_realloc_node, which
         * is not called recursively on allocations
@@ -2408,8 +3099,9 @@ again:
                struct btrfs_space_info *sinfo;
 
                sinfo = __find_space_info(root->fs_info, data);
-               printk("allocation failed flags %Lu, wanted %Lu\n",
-                      data, num_bytes);
+               printk(KERN_ERR "btrfs allocation failed flags %llu, "
+                      "wanted %llu\n", (unsigned long long)data,
+                      (unsigned long long)num_bytes);
                dump_space_info(sinfo, num_bytes);
                BUG();
        }
@@ -2420,15 +3112,22 @@ again:
 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
 {
        struct btrfs_block_group_cache *cache;
+       int ret = 0;
 
        cache = btrfs_lookup_block_group(root->fs_info, start);
        if (!cache) {
-               printk(KERN_ERR "Unable to find block group for %Lu\n", start);
+               printk(KERN_ERR "Unable to find block group for %llu\n",
+                      (unsigned long long)start);
                return -ENOSPC;
        }
+
+       ret = btrfs_discard_extent(root, start, len);
+
        btrfs_add_free_space(cache, start, len);
+       put_block_group(cache);
        update_reserved_extents(root, start, len, 0);
-       return 0;
+
+       return ret;
 }
 
 int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
@@ -2468,14 +3167,14 @@ static int __btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans,
                parent = ins->objectid;
 
        /* block accounting for super block */
-       spin_lock_irq(&info->delalloc_lock);
+       spin_lock(&info->delalloc_lock);
        super_used = btrfs_super_bytes_used(&info->super_copy);
        btrfs_set_super_bytes_used(&info->super_copy, super_used + num_bytes);
-       spin_unlock_irq(&info->delalloc_lock);
 
        /* block accounting for root item */
        root_used = btrfs_root_used(&root->root_item);
        btrfs_set_root_used(&root->root_item, root_used + num_bytes);
+       spin_unlock(&info->delalloc_lock);
 
        if (root == extent_root) {
                struct pending_extent_op *extent_op;
@@ -2491,6 +3190,8 @@ static int __btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans,
                extent_op->generation = ref_generation;
                extent_op->orig_generation = 0;
                extent_op->level = (int)owner;
+               INIT_LIST_HEAD(&extent_op->list);
+               extent_op->del = 0;
 
                mutex_lock(&root->fs_info->extent_ins_mutex);
                set_extent_bits(&root->fs_info->extent_ins, ins->objectid,
@@ -2543,10 +3244,12 @@ static int __btrfs_alloc_reserved_extent(struct btrfs_trans_handle *trans,
        }
 
 update_block:
-       ret = update_block_group(trans, root, ins->objectid, ins->offset, 1, 0);
+       ret = update_block_group(trans, root, ins->objectid,
+                                ins->offset, 1, 0);
        if (ret) {
-               printk("update block group failed for %Lu %Lu\n",
-                      ins->objectid, ins->offset);
+               printk(KERN_ERR "btrfs update block group failed for %llu "
+                      "%llu\n", (unsigned long long)ins->objectid,
+                      (unsigned long long)ins->offset);
                BUG();
        }
 out:
@@ -2582,13 +3285,14 @@ int btrfs_alloc_logged_extent(struct btrfs_trans_handle *trans,
        struct btrfs_block_group_cache *block_group;
 
        block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
-       mutex_lock(&block_group->alloc_mutex);
+       mutex_lock(&block_group->cache_mutex);
        cache_block_group(root, block_group);
+       mutex_unlock(&block_group->cache_mutex);
 
-       ret = btrfs_remove_free_space_lock(block_group, ins->objectid,
-                                          ins->offset);
-       mutex_unlock(&block_group->alloc_mutex);
+       ret = btrfs_remove_free_space(block_group, ins->objectid,
+                                     ins->offset);
        BUG_ON(ret);
+       put_block_group(block_group);
        ret = __btrfs_alloc_reserved_extent(trans, root, parent, root_objectid,
                                            ref_generation, owner, ins);
        return ret;
@@ -2727,7 +3431,7 @@ int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans,
        return 0;
 }
 
-static int noinline cache_drop_leaf_ref(struct btrfs_trans_handle *trans,
+static noinline int cache_drop_leaf_ref(struct btrfs_trans_handle *trans,
                                        struct btrfs_root *root,
                                        struct btrfs_leaf_ref *ref)
 {
@@ -2752,15 +3456,15 @@ static int noinline cache_drop_leaf_ref(struct btrfs_trans_handle *trans,
        return 0;
 }
 
-int drop_snap_lookup_refcount(struct btrfs_root *root, u64 start, u64 len,
-                             u32 *refs)
+static int drop_snap_lookup_refcount(struct btrfs_root *root, u64 start,
+                                    u64 len, u32 *refs)
 {
        int ret;
 
        ret = btrfs_lookup_extent_ref(NULL, root, start, len, refs);
        BUG_ON(ret);
 
-#if 0 // some debugging code in case we see problems here
+#if 0 /* some debugging code in case we see problems here */
        /* if the refs count is one, it won't get increased again.  But
         * if the ref count is > 1, someone may be decreasing it at
         * the same time we are.
@@ -2781,8 +3485,8 @@ int drop_snap_lookup_refcount(struct btrfs_root *root, u64 start, u64 len,
                        free_extent_buffer(eb);
                }
                if (*refs == 1) {
-                       printk("block %llu went down to one during drop_snap\n",
-                              (unsigned long long)start);
+                       printk(KERN_ERR "btrfs block %llu went down to one "
+                              "during drop_snap\n", (unsigned long long)start);
                }
 
        }
@@ -2796,7 +3500,7 @@ int drop_snap_lookup_refcount(struct btrfs_root *root, u64 start, u64 len,
  * helper function for drop_snapshot, this walks down the tree dropping ref
  * counts as it goes.
  */
-static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
+static noinline int walk_down_tree(struct btrfs_trans_handle *trans,
                                   struct btrfs_root *root,
                                   struct btrfs_path *path, int *level)
 {
@@ -2823,7 +3527,7 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
        /*
         * walk down to the last node level and free all the leaves
         */
-       while(*level >= 0) {
+       while (*level >= 0) {
                WARN_ON(*level < 0);
                WARN_ON(*level >= BTRFS_MAX_LEVEL);
                cur = path->nodes[*level];
@@ -2883,10 +3587,6 @@ static int noinline walk_down_tree(struct btrfs_trans_handle *trans,
                                *level = 0;
                                break;
                        }
-                       if (printk_ratelimit()) {
-                               printk("leaf ref miss for bytenr %llu\n",
-                                      (unsigned long long)bytenr);
-                       }
                }
                next = btrfs_find_tree_block(root, bytenr, blocksize);
                if (!next || !btrfs_buffer_uptodate(next, ptr_gen)) {
@@ -2948,7 +3648,7 @@ out:
  * walk_down_tree. The main difference is that it checks reference
  * counts while tree blocks are locked.
  */
-static int noinline walk_down_subtree(struct btrfs_trans_handle *trans,
+static noinline int walk_down_subtree(struct btrfs_trans_handle *trans,
                                      struct btrfs_root *root,
                                      struct btrfs_path *path, int *level)
 {
@@ -3037,7 +3737,7 @@ out:
  * to find the first node higher up where we haven't yet gone through
  * all the slots
  */
-static int noinline walk_up_tree(struct btrfs_trans_handle *trans,
+static noinline int walk_up_tree(struct btrfs_trans_handle *trans,
                                 struct btrfs_root *root,
                                 struct btrfs_path *path,
                                 int *level, int max_level)
@@ -3146,7 +3846,7 @@ int btrfs_drop_snapshot(struct btrfs_trans_handle *trans, struct btrfs_root
                        }
                }
        }
-       while(1) {
+       while (1) {
                wret = walk_down_tree(trans, root, path, &level);
                if (wret > 0)
                        break;
@@ -3227,7 +3927,7 @@ static unsigned long calc_ra(unsigned long start, unsigned long last,
        return min(last, start + nr - 1);
 }
 
-static int noinline relocate_inode_pages(struct inode *inode, u64 start,
+static noinline int relocate_inode_pages(struct inode *inode, u64 start,
                                         u64 len)
 {
        u64 page_start;
@@ -3298,10 +3998,10 @@ again:
                }
                set_page_extent_mapped(page);
 
-               btrfs_set_extent_delalloc(inode, page_start, page_end);
                if (i == first_index)
                        set_extent_bits(io_tree, page_start, page_end,
                                        EXTENT_BOUNDARY, GFP_NOFS);
+               btrfs_set_extent_delalloc(inode, page_start, page_end);
 
                set_page_dirty(page);
                total_dirty++;
@@ -3318,7 +4018,7 @@ out_unlock:
        return ret;
 }
 
-static int noinline relocate_data_extent(struct inode *reloc_inode,
+static noinline int relocate_data_extent(struct inode *reloc_inode,
                                         struct btrfs_key *extent_key,
                                         u64 offset)
 {
@@ -3388,12 +4088,13 @@ static int is_cowonly_root(u64 root_objectid)
            root_objectid == BTRFS_EXTENT_TREE_OBJECTID ||
            root_objectid == BTRFS_CHUNK_TREE_OBJECTID ||
            root_objectid == BTRFS_DEV_TREE_OBJECTID ||
-           root_objectid == BTRFS_TREE_LOG_OBJECTID)
+           root_objectid == BTRFS_TREE_LOG_OBJECTID ||
+           root_objectid == BTRFS_CSUM_TREE_OBJECTID)
                return 1;
        return 0;
 }
 
-static int noinline __next_ref_path(struct btrfs_trans_handle *trans,
+static noinline int __next_ref_path(struct btrfs_trans_handle *trans,
                                    struct btrfs_root *extent_root,
                                    struct btrfs_ref_path *ref_path,
                                    int first_time)
@@ -3425,11 +4126,10 @@ walk_down:
                if (level < ref_path->lowest_level)
                        break;
 
-               if (level >= 0) {
+               if (level >= 0)
                        bytenr = ref_path->nodes[level];
-               } else {
+               else
                        bytenr = ref_path->extent_start;
-               }
                BUG_ON(bytenr == 0);
 
                parent = ref_path->nodes[level + 1];
@@ -3476,11 +4176,12 @@ walk_up:
        level = ref_path->current_level;
        while (level < BTRFS_MAX_LEVEL - 1) {
                u64 ref_objectid;
-               if (level >= 0) {
+
+               if (level >= 0)
                        bytenr = ref_path->nodes[level];
-               } else {
+               else
                        bytenr = ref_path->extent_start;
-               }
+
                BUG_ON(bytenr == 0);
 
                key.objectid = bytenr;
@@ -3605,7 +4306,7 @@ static int btrfs_next_ref_path(struct btrfs_trans_handle *trans,
        return __next_ref_path(trans, extent_root, ref_path, 0);
 }
 
-static int noinline get_new_locations(struct inode *reloc_inode,
+static noinline int get_new_locations(struct inode *reloc_inode,
                                      struct btrfs_key *extent_key,
                                      u64 offset, int no_fragment,
                                      struct disk_extent **extents,
@@ -3708,7 +4409,7 @@ static int noinline get_new_locations(struct inode *reloc_inode,
                path->slots[0]++;
        }
 
-       WARN_ON(cur_pos + offset > last_byte);
+       BUG_ON(cur_pos + offset > last_byte);
        if (cur_pos + offset < last_byte) {
                ret = -ENOENT;
                goto out;
@@ -3726,7 +4427,7 @@ out:
        return ret;
 }
 
-static int noinline replace_one_extent(struct btrfs_trans_handle *trans,
+static noinline int replace_one_extent(struct btrfs_trans_handle *trans,
                                        struct btrfs_root *root,
                                        struct btrfs_path *path,
                                        struct btrfs_key *extent_key,
@@ -4084,7 +4785,7 @@ int btrfs_reloc_tree_cache_ref(struct btrfs_trans_handle *trans,
        return 0;
 }
 
-static int noinline invalidate_extent_cache(struct btrfs_root *root,
+static noinline int invalidate_extent_cache(struct btrfs_root *root,
                                        struct extent_buffer *leaf,
                                        struct btrfs_block_group_cache *group,
                                        struct btrfs_root *target_root)
@@ -4132,7 +4833,7 @@ static int noinline invalidate_extent_cache(struct btrfs_root *root,
        return 0;
 }
 
-static int noinline replace_extents_in_leaf(struct btrfs_trans_handle *trans,
+static noinline int replace_extents_in_leaf(struct btrfs_trans_handle *trans,
                                        struct btrfs_root *root,
                                        struct extent_buffer *leaf,
                                        struct btrfs_block_group_cache *group,
@@ -4341,7 +5042,7 @@ int btrfs_cleanup_reloc_trees(struct btrfs_root *root)
        return 0;
 }
 
-static int noinline init_reloc_tree(struct btrfs_trans_handle *trans,
+static noinline int init_reloc_tree(struct btrfs_trans_handle *trans,
                                    struct btrfs_root *root)
 {
        struct btrfs_root *reloc_root;
@@ -4408,7 +5109,7 @@ static int noinline init_reloc_tree(struct btrfs_trans_handle *trans,
  * tree blocks are shared between reloc trees, so they are also shared
  * between subvols.
  */
-static int noinline relocate_one_path(struct btrfs_trans_handle *trans,
+static noinline int relocate_one_path(struct btrfs_trans_handle *trans,
                                      struct btrfs_root *root,
                                      struct btrfs_path *path,
                                      struct btrfs_key *first_key,
@@ -4467,7 +5168,8 @@ static int noinline relocate_one_path(struct btrfs_trans_handle *trans,
                        else
                                btrfs_node_key_to_cpu(eb, &keys[level], 0);
                }
-               if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
+               if (nodes[0] &&
+                   ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
                        eb = path->nodes[0];
                        ret = replace_extents_in_leaf(trans, reloc_root, eb,
                                                      group, reloc_inode);
@@ -4504,7 +5206,7 @@ static int noinline relocate_one_path(struct btrfs_trans_handle *trans,
        return 0;
 }
 
-static int noinline relocate_tree_block(struct btrfs_trans_handle *trans,
+static noinline int relocate_tree_block(struct btrfs_trans_handle *trans,
                                        struct btrfs_root *root,
                                        struct btrfs_path *path,
                                        struct btrfs_key *first_key,
@@ -4522,7 +5224,7 @@ static int noinline relocate_tree_block(struct btrfs_trans_handle *trans,
        return 0;
 }
 
-static int noinline del_extent_zero(struct btrfs_trans_handle *trans,
+static noinline int del_extent_zero(struct btrfs_trans_handle *trans,
                                    struct btrfs_root *extent_root,
                                    struct btrfs_path *path,
                                    struct btrfs_key *extent_key)
@@ -4538,7 +5240,7 @@ out:
        return ret;
 }
 
-static struct btrfs_root noinline *read_ref_root(struct btrfs_fs_info *fs_info,
+static noinline struct btrfs_root *read_ref_root(struct btrfs_fs_info *fs_info,
                                                struct btrfs_ref_path *ref_path)
 {
        struct btrfs_key root_key;
@@ -4553,7 +5255,7 @@ static struct btrfs_root noinline *read_ref_root(struct btrfs_fs_info *fs_info,
        return btrfs_read_fs_root_no_name(fs_info, &root_key);
 }
 
-static int noinline relocate_one_extent(struct btrfs_root *extent_root,
+static noinline int relocate_one_extent(struct btrfs_root *extent_root,
                                        struct btrfs_path *path,
                                        struct btrfs_key *extent_key,
                                        struct btrfs_block_group_cache *group,
@@ -4581,8 +5283,8 @@ static int noinline relocate_one_extent(struct btrfs_root *extent_root,
 
        ref_path = kmalloc(sizeof(*ref_path), GFP_NOFS);
        if (!ref_path) {
-              ret = -ENOMEM;
-              goto out;
+               ret = -ENOMEM;
+               goto out;
        }
 
        for (loops = 0; ; loops++) {
@@ -4649,8 +5351,20 @@ static int noinline relocate_one_extent(struct btrfs_root *extent_root,
                        prev_block = block_start;
                }
 
-               if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID &&
-                   pass >= 2) {
+               btrfs_record_root_in_trans(found_root);
+               if (ref_path->owner_objectid >= BTRFS_FIRST_FREE_OBJECTID) {
+                       /*
+                        * try to update data extent references while
+                        * keeping metadata shared between snapshots.
+                        */
+                       if (pass == 1) {
+                               ret = relocate_one_path(trans, found_root,
+                                               path, &first_key, ref_path,
+                                               group, reloc_inode);
+                               if (ret < 0)
+                                       goto out;
+                               continue;
+                       }
                        /*
                         * use fallback method to process the remaining
                         * references.
@@ -4668,28 +5382,13 @@ static int noinline relocate_one_extent(struct btrfs_root *extent_root,
                                if (ret)
                                        goto out;
                        }
-                       btrfs_record_root_in_trans(found_root);
                        ret = replace_one_extent(trans, found_root,
                                                path, extent_key,
                                                &first_key, ref_path,
                                                new_extents, nr_extents);
-                       if (ret < 0)
-                               goto out;
-                       continue;
-               }
-
-               btrfs_record_root_in_trans(found_root);
-               if (ref_path->owner_objectid < BTRFS_FIRST_FREE_OBJECTID) {
+               } else {
                        ret = relocate_tree_block(trans, found_root, path,
                                                  &first_key, ref_path);
-               } else {
-                       /*
-                        * try to update data extent references while
-                        * keeping metadata shared between snapshots.
-                        */
-                       ret = relocate_one_path(trans, found_root, path,
-                                               &first_key, ref_path,
-                                               group, reloc_inode);
                }
                if (ret < 0)
                        goto out;
@@ -4708,7 +5407,7 @@ static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
        u64 stripped = BTRFS_BLOCK_GROUP_RAID0 |
                BTRFS_BLOCK_GROUP_RAID1 | BTRFS_BLOCK_GROUP_RAID10;
 
-       num_devices = root->fs_info->fs_devices->num_devices;
+       num_devices = root->fs_info->fs_devices->rw_devices;
        if (num_devices == 1) {
                stripped |= BTRFS_BLOCK_GROUP_DUP;
                stripped = flags & ~stripped;
@@ -4740,7 +5439,7 @@ static u64 update_block_group_flags(struct btrfs_root *root, u64 flags)
        return flags;
 }
 
-int __alloc_chunk_for_shrink(struct btrfs_root *root,
+static int __alloc_chunk_for_shrink(struct btrfs_root *root,
                     struct btrfs_block_group_cache *shrink_block_group,
                     int force)
 {
@@ -4797,8 +5496,7 @@ static int __insert_orphan_inode(struct btrfs_trans_handle *trans,
        btrfs_set_inode_generation(leaf, item, 1);
        btrfs_set_inode_size(leaf, item, size);
        btrfs_set_inode_mode(leaf, item, S_IFREG | 0600);
-       btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NODATASUM |
-                                         BTRFS_INODE_NOCOMPRESS);
+       btrfs_set_inode_flags(leaf, item, BTRFS_INODE_NOCOMPRESS);
        btrfs_mark_buffer_dirty(leaf);
        btrfs_release_path(root, path);
 out:
@@ -4806,7 +5504,7 @@ out:
        return ret;
 }
 
-static struct inode noinline *create_reloc_inode(struct btrfs_fs_info *fs_info,
+static noinline struct inode *create_reloc_inode(struct btrfs_fs_info *fs_info,
                                        struct btrfs_block_group_cache *group)
 {
        struct inode *inode = NULL;
@@ -4850,6 +5548,7 @@ static struct inode noinline *create_reloc_inode(struct btrfs_fs_info *fs_info,
        } else {
                BUG_ON(1);
        }
+       BTRFS_I(inode)->index_cnt = group->key.objectid;
 
        err = btrfs_orphan_add(trans, inode);
 out:
@@ -4862,6 +5561,47 @@ out:
        return inode;
 }
 
+int btrfs_reloc_clone_csums(struct inode *inode, u64 file_pos, u64 len)
+{
+
+       struct btrfs_ordered_sum *sums;
+       struct btrfs_sector_sum *sector_sum;
+       struct btrfs_ordered_extent *ordered;
+       struct btrfs_root *root = BTRFS_I(inode)->root;
+       struct list_head list;
+       size_t offset;
+       int ret;
+       u64 disk_bytenr;
+
+       INIT_LIST_HEAD(&list);
+
+       ordered = btrfs_lookup_ordered_extent(inode, file_pos);
+       BUG_ON(ordered->file_offset != file_pos || ordered->len != len);
+
+       disk_bytenr = file_pos + BTRFS_I(inode)->index_cnt;
+       ret = btrfs_lookup_csums_range(root->fs_info->csum_root, disk_bytenr,
+                                      disk_bytenr + len - 1, &list);
+
+       while (!list_empty(&list)) {
+               sums = list_entry(list.next, struct btrfs_ordered_sum, list);
+               list_del_init(&sums->list);
+
+               sector_sum = sums->sums;
+               sums->bytenr = ordered->start;
+
+               offset = 0;
+               while (offset < sums->len) {
+                       sector_sum->bytenr += ordered->start - disk_bytenr;
+                       sector_sum++;
+                       offset += root->sectorsize;
+               }
+
+               btrfs_add_ordered_sum(inode, ordered, sums);
+       }
+       btrfs_put_ordered_extent(ordered);
+       return 0;
+}
+
 int btrfs_relocate_block_group(struct btrfs_root *root, u64 group_start)
 {
        struct btrfs_trans_handle *trans;
@@ -4884,7 +5624,7 @@ int btrfs_relocate_block_group(struct btrfs_root *root, u64 group_start)
        block_group = btrfs_lookup_block_group(info, group_start);
        BUG_ON(!block_group);
 
-       printk("btrfs relocating block group %llu flags %llu\n",
+       printk(KERN_INFO "btrfs relocating block group %llu flags %llu\n",
               (unsigned long long)block_group->key.objectid,
               (unsigned long long)block_group->flags);
 
@@ -4895,8 +5635,7 @@ int btrfs_relocate_block_group(struct btrfs_root *root, u64 group_start)
        BUG_ON(IS_ERR(reloc_inode));
 
        __alloc_chunk_for_shrink(root, block_group, 1);
-       block_group->ro = 1;
-       block_group->space_info->total_bytes -= block_group->key.offset;
+       set_block_group_readonly(block_group);
 
        btrfs_start_delalloc_inodes(info->tree_root);
        btrfs_wait_ordered_extents(info->tree_root, 0);
@@ -4917,7 +5656,7 @@ again:
        btrfs_remove_leaf_refs(info->tree_root, (u64)-1, 1);
        mutex_unlock(&root->fs_info->cleaner_mutex);
 
-       while(1) {
+       while (1) {
                ret = btrfs_search_slot(NULL, root, &key, path, 0, 0);
                if (ret < 0)
                        goto out;
@@ -4977,11 +5716,10 @@ next:
        if (pass == 0) {
                btrfs_wait_ordered_range(reloc_inode, 0, (u64)-1);
                invalidate_mapping_pages(reloc_inode->i_mapping, 0, -1);
-               WARN_ON(reloc_inode->i_mapping->nrpages);
        }
 
        if (total_found > 0) {
-               printk("btrfs found %llu extents in pass %d\n",
+               printk(KERN_INFO "btrfs found %llu extents in pass %d\n",
                       (unsigned long long)total_found, pass);
                pass++;
                if (total_found == skipped && pass > 2) {
@@ -5004,14 +5742,15 @@ next:
        WARN_ON(block_group->reserved > 0);
        WARN_ON(btrfs_block_group_used(&block_group->item) > 0);
        spin_unlock(&block_group->lock);
+       put_block_group(block_group);
        ret = 0;
 out:
        btrfs_free_path(path);
        return ret;
 }
 
-int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path,
-                          struct btrfs_key *key)
+static int find_first_block_group(struct btrfs_root *root,
+               struct btrfs_path *path, struct btrfs_key *key)
 {
        int ret = 0;
        struct btrfs_key found_key;
@@ -5022,7 +5761,7 @@ int find_first_block_group(struct btrfs_root *root, struct btrfs_path *path,
        if (ret < 0)
                goto out;
 
-       while(1) {
+       while (1) {
                slot = path->slots[0];
                leaf = path->nodes[0];
                if (slot >= btrfs_header_nritems(leaf)) {
@@ -5064,6 +5803,8 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
                down_write(&block_group->space_info->groups_sem);
                list_del(&block_group->list);
                up_write(&block_group->space_info->groups_sem);
+
+               WARN_ON(atomic_read(&block_group->count) != 1);
                kfree(block_group);
 
                spin_lock(&info->block_group_cache_lock);
@@ -5091,7 +5832,7 @@ int btrfs_read_block_groups(struct btrfs_root *root)
        if (!path)
                return -ENOMEM;
 
-       while(1) {
+       while (1) {
                ret = find_first_block_group(root, path, &key);
                if (ret > 0) {
                        ret = 0;
@@ -5108,8 +5849,10 @@ int btrfs_read_block_groups(struct btrfs_root *root)
                        break;
                }
 
+               atomic_set(&cache->count, 1);
                spin_lock_init(&cache->lock);
                mutex_init(&cache->alloc_mutex);
+               mutex_init(&cache->cache_mutex);
                INIT_LIST_HEAD(&cache->list);
                read_extent_buffer(leaf, &cache->item,
                                   btrfs_item_ptr_offset(leaf, path->slots[0]),
@@ -5133,6 +5876,8 @@ int btrfs_read_block_groups(struct btrfs_root *root)
                BUG_ON(ret);
 
                set_avail_alloc_bits(root->fs_info, cache->flags);
+               if (btrfs_chunk_readonly(root, cache->key.objectid))
+                       set_block_group_readonly(cache);
        }
        ret = 0;
 error:
@@ -5159,10 +5904,12 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
 
        cache->key.objectid = chunk_offset;
        cache->key.offset = size;
+       cache->key.type = BTRFS_BLOCK_GROUP_ITEM_KEY;
+       atomic_set(&cache->count, 1);
        spin_lock_init(&cache->lock);
        mutex_init(&cache->alloc_mutex);
+       mutex_init(&cache->cache_mutex);
        INIT_LIST_HEAD(&cache->list);
-       btrfs_set_key_type(&cache->key, BTRFS_BLOCK_GROUP_ITEM_KEY);
 
        btrfs_set_block_group_used(&cache->item, bytes_used);
        btrfs_set_block_group_chunk_objectid(&cache->item, chunk_objectid);
@@ -5203,6 +5950,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
 
        block_group = btrfs_lookup_block_group(root->fs_info, group_start);
        BUG_ON(!block_group);
+       BUG_ON(!block_group->ro);
 
        memcpy(&key, &block_group->key, sizeof(key));
 
@@ -5216,10 +5964,14 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
        list_del(&block_group->list);
        up_write(&block_group->space_info->groups_sem);
 
-       /*
-       memset(shrink_block_group, 0, sizeof(*shrink_block_group));
-       kfree(shrink_block_group);
-       */
+       spin_lock(&block_group->space_info->lock);
+       block_group->space_info->total_bytes -= block_group->key.offset;
+       block_group->space_info->bytes_readonly -= block_group->key.offset;
+       spin_unlock(&block_group->space_info->lock);
+       block_group->space_info->full = 0;
+
+       put_block_group(block_group);
+       put_block_group(block_group);
 
        ret = btrfs_search_slot(trans, root, &key, path, -1, 1);
        if (ret > 0)