5 files changed, 382 insertions, 259 deletions

diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h
index 732d5b884aa7..3b6df7140575 100644
--- a/fs/btrfs/ctree.h
+++ b/fs/btrfs/ctree.h
@@ -726,6 +726,15 @@ enum btrfs_caching_type {
         BTRFS_CACHE_FINISHED    = 2,
 };
 
+struct btrfs_caching_control {
+        struct list_head list;
+        struct mutex mutex;
+        wait_queue_head_t wait;
+        struct btrfs_block_group_cache *block_group;
+        u64 progress;
+        atomic_t count;
+};
+
 struct btrfs_block_group_cache {
         struct btrfs_key key;
         struct btrfs_block_group_item item;
@@ -742,8 +751,9 @@ struct btrfs_block_group_cache {
         int dirty;
 
         /* cache tracking stuff */
-        wait_queue_head_t caching_q;
         int cached;
+        struct btrfs_caching_control *caching_ctl;
+        u64 last_byte_to_unpin;
 
         struct btrfs_space_info *space_info;
 
@@ -788,7 +798,8 @@ struct btrfs_fs_info {
         spinlock_t block_group_cache_lock;
         struct rb_root block_group_cache_tree;
 
-        struct extent_io_tree pinned_extents;
+        struct extent_io_tree freed_extents[2];
+        struct extent_io_tree *pinned_extents;
 
         /* logical->physical extent mapping */
         struct btrfs_mapping_tree mapping_tree;
@@ -825,8 +836,6 @@ struct btrfs_fs_info {
         struct mutex drop_mutex;
         struct mutex volume_mutex;
         struct mutex tree_reloc_mutex;
-        struct rw_semaphore extent_commit_sem;
-
         /*
          * this protects the ordered operations list only while we are
          * processing all of the entries on it.  This way we make
@@ -835,10 +844,12 @@ struct btrfs_fs_info {
          * before jumping into the main commit.
          */
         struct mutex ordered_operations_mutex;
+        struct rw_semaphore extent_commit_sem;
 
         struct list_head trans_list;
         struct list_head hashers;
         struct list_head dead_roots;
+        struct list_head caching_block_groups;
 
         atomic_t nr_async_submits;
         atomic_t async_submit_draining;
@@ -1920,8 +1931,8 @@ void btrfs_put_block_group(struct btrfs_block_group_cache *cache);
 int btrfs_run_delayed_refs(struct btrfs_trans_handle *trans,
                            struct btrfs_root *root, unsigned long count);
 int btrfs_lookup_extent(struct btrfs_root *root, u64 start, u64 len);
-int btrfs_update_pinned_extents(struct btrfs_root *root,
-                                u64 bytenr, u64 num, int pin);
+int btrfs_pin_extent(struct btrfs_root *root,
+                     u64 bytenr, u64 num, int reserved);
 int btrfs_drop_leaf_ref(struct btrfs_trans_handle *trans,
                         struct btrfs_root *root, struct extent_buffer *leaf);
 int btrfs_cross_ref_exist(struct btrfs_trans_handle *trans,
@@ -1971,9 +1982,10 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans,
                       u64 root_objectid, u64 owner, u64 offset);
 
 int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len);
+int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
+                                struct btrfs_root *root);
 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
-                               struct btrfs_root *root,
-                               struct extent_io_tree *unpin);
+                               struct btrfs_root *root);
 int btrfs_inc_extent_ref(struct btrfs_trans_handle *trans,
                          struct btrfs_root *root,
                          u64 bytenr, u64 num_bytes, u64 parent,
@@ -2006,7 +2018,6 @@ void btrfs_delalloc_reserve_space(struct btrfs_root *root, struct inode *inode,
                                  u64 bytes);
 void btrfs_delalloc_free_space(struct btrfs_root *root, struct inode *inode,
                               u64 bytes);
-void btrfs_free_pinned_extents(struct btrfs_fs_info *info);
 /* ctree.c */
 int btrfs_bin_search(struct extent_buffer *eb, struct btrfs_key *key,
                      int level, int *slot);
diff --git a/fs/btrfs/disk-io.c b/fs/btrfs/disk-io.c
index 253da7e01ab3..16dae122dda4 100644
--- a/fs/btrfs/disk-io.c
+++ b/fs/btrfs/disk-io.c
@@ -1563,6 +1563,7 @@ struct btrfs_root *open_ctree(struct super_block *sb,
         INIT_LIST_HEAD(&fs_info->hashers);
         INIT_LIST_HEAD(&fs_info->delalloc_inodes);
         INIT_LIST_HEAD(&fs_info->ordered_operations);
+        INIT_LIST_HEAD(&fs_info->caching_block_groups);
         spin_lock_init(&fs_info->delalloc_lock);
         spin_lock_init(&fs_info->new_trans_lock);
         spin_lock_init(&fs_info->ref_cache_lock);
@@ -1621,8 +1622,11 @@ struct btrfs_root *open_ctree(struct super_block *sb,
         spin_lock_init(&fs_info->block_group_cache_lock);
         fs_info->block_group_cache_tree.rb_node = NULL;
 
-        extent_io_tree_init(&fs_info->pinned_extents,
+        extent_io_tree_init(&fs_info->freed_extents[0],
                              fs_info->btree_inode->i_mapping, GFP_NOFS);
+        extent_io_tree_init(&fs_info->freed_extents[1],
+                             fs_info->btree_inode->i_mapping, GFP_NOFS);
+        fs_info->pinned_extents = &fs_info->freed_extents[0];
         fs_info->do_barriers = 1;
 
         BTRFS_I(fs_info->btree_inode)->root = tree_root;
@@ -2359,7 +2363,6 @@ int close_ctree(struct btrfs_root *root)
         free_extent_buffer(root->fs_info->csum_root->commit_root);
 
         btrfs_free_block_groups(root->fs_info);
-        btrfs_free_pinned_extents(root->fs_info);
 
         del_fs_roots(fs_info);
 
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index edd86ae9e149..9bcb9c09c3b8 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -32,12 +32,12 @@
 #include "locking.h"
 #include "free-space-cache.h"
 
-static int update_reserved_extents(struct btrfs_root *root,
-                                   u64 bytenr, u64 num, int reserve);
 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 update_reserved_extents(struct btrfs_block_group_cache *cache,
+                                   u64 num_bytes, int reserve);
 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
                                 struct btrfs_root *root,
                                 u64 bytenr, u64 num_bytes, u64 parent,
@@ -57,10 +57,17 @@ static int alloc_reserved_tree_block(struct btrfs_trans_handle *trans,
                                      u64 parent, u64 root_objectid,
                                      u64 flags, struct btrfs_disk_key *key,
                                      int level, struct btrfs_key *ins);
-
 static int do_chunk_alloc(struct btrfs_trans_handle *trans,
                           struct btrfs_root *extent_root, u64 alloc_bytes,
                           u64 flags, int force);
+static int pin_down_bytes(struct btrfs_trans_handle *trans,
+                          struct btrfs_root *root,
+                          struct btrfs_path *path,
+                          u64 bytenr, u64 num_bytes,
+                          int is_data, int reserved,
+                          struct extent_buffer **must_clean);
+static int find_next_key(struct btrfs_path *path, int level,
+                         struct btrfs_key *key);
 
 static noinline int
 block_group_cache_done(struct btrfs_block_group_cache *cache)
@@ -153,34 +160,34 @@ block_group_cache_tree_search(struct btrfs_fs_info *info, u64 bytenr,
         return ret;
 }
 
-/*
- * We always set EXTENT_LOCKED for the super mirror extents so we don't
- * overwrite them, so those bits need to be unset.  Also, if we are unmounting
- * with pinned extents still sitting there because we had a block group caching,
- * we need to clear those now, since we are done.
- */
-void btrfs_free_pinned_extents(struct btrfs_fs_info *info)
+static int add_excluded_extent(struct btrfs_root *root,
+                               u64 start, u64 num_bytes)
 {
-        u64 start, end, last = 0;
-        int ret;
+        u64 end = start + num_bytes - 1;
+        set_extent_bits(&root->fs_info->freed_extents[0],
+                        start, end, EXTENT_UPTODATE, GFP_NOFS);
+        set_extent_bits(&root->fs_info->freed_extents[1],
+                        start, end, EXTENT_UPTODATE, GFP_NOFS);
+        return 0;
+}
 
-        while (1) {
-                ret = find_first_extent_bit(&info->pinned_extents, last,
-                                            &start, &end,
-                                            EXTENT_LOCKED|EXTENT_DIRTY);
-                if (ret)
-                        break;
+static void free_excluded_extents(struct btrfs_root *root,
+                                  struct btrfs_block_group_cache *cache)
+{
+        u64 start, end;
 
-                clear_extent_bits(&info->pinned_extents, start, end,
-                                  EXTENT_LOCKED|EXTENT_DIRTY, GFP_NOFS);
-                last = end+1;
-        }
+        start = cache->key.objectid;
+        end = start + cache->key.offset - 1;
+
+        clear_extent_bits(&root->fs_info->freed_extents[0],
+                          start, end, EXTENT_UPTODATE, GFP_NOFS);
+        clear_extent_bits(&root->fs_info->freed_extents[1],
+                          start, end, EXTENT_UPTODATE, GFP_NOFS);
 }
 
-static int remove_sb_from_cache(struct btrfs_root *root,
-                                struct btrfs_block_group_cache *cache)
+static int exclude_super_stripes(struct btrfs_root *root,
+                                 struct btrfs_block_group_cache *cache)
 {
-        struct btrfs_fs_info *fs_info = root->fs_info;
         u64 bytenr;
         u64 *logical;
         int stripe_len;
@@ -192,17 +199,41 @@ static int remove_sb_from_cache(struct btrfs_root *root,
                                        cache->key.objectid, bytenr,
                                        0, &logical, &nr, &stripe_len);
                 BUG_ON(ret);
+
                 while (nr--) {
-                        try_lock_extent(&fs_info->pinned_extents,
-                                        logical[nr],
-                                        logical[nr] + stripe_len - 1, GFP_NOFS);
+                        ret = add_excluded_extent(root, logical[nr],
+                                                  stripe_len);
+                        BUG_ON(ret);
                 }
+
                 kfree(logical);
         }
-
         return 0;
 }
 
+static struct btrfs_caching_control *
+get_caching_control(struct btrfs_block_group_cache *cache)
+{
+        struct btrfs_caching_control *ctl;
+
+        spin_lock(&cache->lock);
+        if (cache->cached != BTRFS_CACHE_STARTED) {
+                spin_unlock(&cache->lock);
+                return NULL;
+        }
+
+        ctl = cache->caching_ctl;
+        atomic_inc(&ctl->count);
+        spin_unlock(&cache->lock);
+        return ctl;
+}
+
+static void put_caching_control(struct btrfs_caching_control *ctl)
+{
+        if (atomic_dec_and_test(&ctl->count))
+                kfree(ctl);
+}
+
 /*
  * this is only called by cache_block_group, since we could have freed extents
  * we need to check the pinned_extents for any extents that can't be used yet
@@ -215,9 +246,9 @@ static u64 add_new_free_space(struct btrfs_block_group_cache *block_group,
         int ret;
 
         while (start < end) {
-                ret = find_first_extent_bit(&info->pinned_extents, start,
+                ret = find_first_extent_bit(info->pinned_extents, start,
                                             &extent_start, &extent_end,
-                                            EXTENT_DIRTY|EXTENT_LOCKED);
+                                            EXTENT_DIRTY | EXTENT_UPTODATE);
                 if (ret)
                         break;
 
@@ -249,22 +280,24 @@ static int caching_kthread(void *data)
 {
         struct btrfs_block_group_cache *block_group = data;
         struct btrfs_fs_info *fs_info = block_group->fs_info;
-        u64 last = 0;
+        struct btrfs_caching_control *caching_ctl = block_group->caching_ctl;
+        struct btrfs_root *extent_root = fs_info->extent_root;
         struct btrfs_path *path;
-        int ret = 0;
-        struct btrfs_key key;
         struct extent_buffer *leaf;
-        int slot;
+        struct btrfs_key key;
         u64 total_found = 0;
-
-        BUG_ON(!fs_info);
+        u64 last = 0;
+        u32 nritems;
+        int ret = 0;
 
         path = btrfs_alloc_path();
         if (!path)
                 return -ENOMEM;
 
-        atomic_inc(&block_group->space_info->caching_threads);
+        exclude_super_stripes(extent_root, block_group);
+
         last = max_t(u64, block_group->key.objectid, BTRFS_SUPER_INFO_OFFSET);
+
         /*
          * We don't want to deadlock with somebody trying to allocate a new
          * extent for the extent root while also trying to search the extent
@@ -277,74 +310,64 @@ static int caching_kthread(void *data)
 
         key.objectid = last;
         key.offset = 0;
-        btrfs_set_key_type(&key, BTRFS_EXTENT_ITEM_KEY);
+        key.type = BTRFS_EXTENT_ITEM_KEY;
 again:
+        mutex_lock(&caching_ctl->mutex);
         /* need to make sure the commit_root doesn't disappear */
         down_read(&fs_info->extent_commit_sem);
 
-        ret = btrfs_search_slot(NULL, fs_info->extent_root, &key, path, 0, 0);
+        ret = btrfs_search_slot(NULL, extent_root, &key, path, 0, 0);
         if (ret < 0)
                 goto err;
 
+        leaf = path->nodes[0];
+        nritems = btrfs_header_nritems(leaf);
+
         while (1) {
                 smp_mb();
-                if (block_group->fs_info->closing > 1) {
+                if (fs_info->closing > 1) {
                         last = (u64)-1;
                         break;
                 }
 
-                leaf = path->nodes[0];
-                slot = path->slots[0];
-                if (slot >= btrfs_header_nritems(leaf)) {
-                        ret = btrfs_next_leaf(fs_info->extent_root, path);
-                        if (ret < 0)
-                                goto err;
-                        else if (ret)
+                if (path->slots[0] < nritems) {
+                        btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
+                } else {
+                        ret = find_next_key(path, 0, &key);
+                        if (ret)
                                 break;
 
-                        if (need_resched() ||
-                            btrfs_transaction_in_commit(fs_info)) {
-                                leaf = path->nodes[0];
-
-                                /* this shouldn't happen, but if the
-                                 * leaf is empty just move on.
-                                 */
-                                if (btrfs_header_nritems(leaf) == 0)
-                                        break;
-                                /*
-                                 * we need to copy the key out so that
-                                 * we are sure the next search advances
-                                 * us forward in the btree.
-                                 */
-                                btrfs_item_key_to_cpu(leaf, &key, 0);
-                                btrfs_release_path(fs_info->extent_root, path);
-                                up_read(&fs_info->extent_commit_sem);
+                        caching_ctl->progress = last;
+                        btrfs_release_path(extent_root, path);
+                        up_read(&fs_info->extent_commit_sem);
+                        mutex_unlock(&caching_ctl->mutex);
+                        if (btrfs_transaction_in_commit(fs_info))
                                 schedule_timeout(1);
-                                goto again;
-                        }
+                        else
+                                cond_resched();
+                        goto again;
+                }
 
+                if (key.objectid < block_group->key.objectid) {
+                        path->slots[0]++;
                         continue;
                 }
-                btrfs_item_key_to_cpu(leaf, &key, slot);
-                if (key.objectid < block_group->key.objectid)
-                        goto next;
 
                 if (key.objectid >= block_group->key.objectid +
                     block_group->key.offset)
                         break;
 
-                if (btrfs_key_type(&key) == BTRFS_EXTENT_ITEM_KEY) {
+                if (key.type == BTRFS_EXTENT_ITEM_KEY) {
                         total_found += add_new_free_space(block_group,
                                                           fs_info, last,
                                                           key.objectid);
                         last = key.objectid + key.offset;
-                }
 
-                if (total_found > (1024 * 1024 * 2)) {
-                        total_found = 0;
-                        wake_up(&block_group->caching_q);
+                        if (total_found > (1024 * 1024 * 2)) {
+                                total_found = 0;
+                                wake_up(&caching_ctl->wait);
+                        }
                 }
-next:
                 path->slots[0]++;
         }
         ret = 0;
@@ -352,33 +375,65 @@ next:
         total_found += add_new_free_space(block_group, fs_info, last,
                                           block_group->key.objectid +
                                           block_group->key.offset);
+        caching_ctl->progress = (u64)-1;
 
         spin_lock(&block_group->lock);
+        block_group->caching_ctl = NULL;
         block_group->cached = BTRFS_CACHE_FINISHED;
         spin_unlock(&block_group->lock);
 
 err:
         btrfs_free_path(path);
         up_read(&fs_info->extent_commit_sem);
-        atomic_dec(&block_group->space_info->caching_threads);
-        wake_up(&block_group->caching_q);
 
+        free_excluded_extents(extent_root, block_group);
+
+        mutex_unlock(&caching_ctl->mutex);
+        wake_up(&caching_ctl->wait);
+
+        put_caching_control(caching_ctl);
+        atomic_dec(&block_group->space_info->caching_threads);
         return 0;
 }
 
 static int cache_block_group(struct btrfs_block_group_cache *cache)
 {
+        struct btrfs_fs_info *fs_info = cache->fs_info;
+        struct btrfs_caching_control *caching_ctl;
         struct task_struct *tsk;
         int ret = 0;
 
+        smp_mb();
+        if (cache->cached != BTRFS_CACHE_NO)
+                return 0;
+
+        caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_KERNEL);
+        BUG_ON(!caching_ctl);
+
+        INIT_LIST_HEAD(&caching_ctl->list);
+        mutex_init(&caching_ctl->mutex);
+        init_waitqueue_head(&caching_ctl->wait);
+        caching_ctl->block_group = cache;
+        caching_ctl->progress = cache->key.objectid;
+        /* one for caching kthread, one for caching block group list */
+        atomic_set(&caching_ctl->count, 2);
+
         spin_lock(&cache->lock);
         if (cache->cached != BTRFS_CACHE_NO) {
                 spin_unlock(&cache->lock);
-                return ret;
+                kfree(caching_ctl);
+                return 0;
         }
+        cache->caching_ctl = caching_ctl;
         cache->cached = BTRFS_CACHE_STARTED;
         spin_unlock(&cache->lock);
 
+        down_write(&fs_info->extent_commit_sem);
+        list_add_tail(&caching_ctl->list, &fs_info->caching_block_groups);
+        up_write(&fs_info->extent_commit_sem);
+
+        atomic_inc(&cache->space_info->caching_threads);
+
         tsk = kthread_run(caching_kthread, cache, "btrfs-cache-%llu\n",
                           cache->key.objectid);
         if (IS_ERR(tsk)) {
@@ -1656,7 +1711,6 @@ static int run_delayed_data_ref(struct btrfs_trans_handle *trans,
                                                  parent, ref_root, flags,
                                                  ref->objectid, ref->offset,
                                                  &ins, node->ref_mod);
-                update_reserved_extents(root, ins.objectid, ins.offset, 0);
         } else if (node->action == BTRFS_ADD_DELAYED_REF) {
                 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
                                              node->num_bytes, parent,
@@ -1782,7 +1836,6 @@ static int run_delayed_tree_ref(struct btrfs_trans_handle *trans,
                                                 extent_op->flags_to_set,
                                                 &extent_op->key,
                                                 ref->level, &ins);
-                update_reserved_extents(root, ins.objectid, ins.offset, 0);
         } else if (node->action == BTRFS_ADD_DELAYED_REF) {
                 ret = __btrfs_inc_extent_ref(trans, root, node->bytenr,
                                              node->num_bytes, parent, ref_root,
@@ -1817,16 +1870,32 @@ static int run_one_delayed_ref(struct btrfs_trans_handle *trans,
                 BUG_ON(extent_op);
                 head = btrfs_delayed_node_to_head(node);
                 if (insert_reserved) {
+                        int mark_free = 0;
+                        struct extent_buffer *must_clean = NULL;
+
+                        ret = pin_down_bytes(trans, root, NULL,
+                                             node->bytenr, node->num_bytes,
+                                             head->is_data, 1, &must_clean);
+                        if (ret > 0)
+                                mark_free = 1;
+
+                        if (must_clean) {
+                                clean_tree_block(NULL, root, must_clean);
+                                btrfs_tree_unlock(must_clean);
+                                free_extent_buffer(must_clean);
+                        }
                         if (head->is_data) {
                                 ret = btrfs_del_csums(trans, root,
                                                       node->bytenr,
                                                       node->num_bytes);
                                 BUG_ON(ret);
                         }
-                        btrfs_update_pinned_extents(root, node->bytenr,
-                                                    node->num_bytes, 1);
-                        update_reserved_extents(root, node->bytenr,
-                                                node->num_bytes, 0);
+                        if (mark_free) {
+                                ret = btrfs_free_reserved_extent(root,
+                                                        node->bytenr,
+                                                        node->num_bytes);
+                                BUG_ON(ret);
+                        }
                 }
                 mutex_unlock(&head->mutex);
                 return 0;
@@ -3008,10 +3077,12 @@ static int update_block_group(struct btrfs_trans_handle *trans,
                 num_bytes = min(total, cache->key.offset - byte_in_group);
                 if (alloc) {
                         old_val += num_bytes;
+                        btrfs_set_block_group_used(&cache->item, old_val);
+                        cache->reserved -= num_bytes;
                         cache->space_info->bytes_used += num_bytes;
+                        cache->space_info->bytes_reserved -= 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 {
@@ -3056,127 +3127,136 @@ static u64 first_logical_byte(struct btrfs_root *root, u64 search_start)
         return bytenr;
 }
 
-int btrfs_update_pinned_extents(struct btrfs_root *root,
-                                u64 bytenr, u64 num, int pin)
+/*
+ * this function must be called within transaction
+ */
+int btrfs_pin_extent(struct btrfs_root *root,
+                     u64 bytenr, u64 num_bytes, int reserved)
 {
-        u64 len;
-        struct btrfs_block_group_cache *cache;
         struct btrfs_fs_info *fs_info = root->fs_info;
+        struct btrfs_block_group_cache *cache;
 
-        if (pin)
-                set_extent_dirty(&fs_info->pinned_extents,
-                                bytenr, bytenr + num - 1, GFP_NOFS);
-
-        while (num > 0) {
-                cache = btrfs_lookup_block_group(fs_info, bytenr);
-                BUG_ON(!cache);
-                len = min(num, cache->key.offset -
-                          (bytenr - cache->key.objectid));
-                if (pin) {
-                        spin_lock(&cache->space_info->lock);
-                        spin_lock(&cache->lock);
-                        cache->pinned += len;
-                        cache->space_info->bytes_pinned += len;
-                        spin_unlock(&cache->lock);
-                        spin_unlock(&cache->space_info->lock);
-                        fs_info->total_pinned += len;
-                } else {
-                        int unpin = 0;
+        cache = btrfs_lookup_block_group(fs_info, bytenr);
+        BUG_ON(!cache);
 
-                        /*
-                         * in order to not race with the block group caching, we
-                         * only want to unpin the extent if we are cached.  If
-                         * we aren't cached, we want to start async caching this
-                         * block group so we can free the extent the next time
-                         * around.
-                         */
-                        spin_lock(&cache->space_info->lock);
-                        spin_lock(&cache->lock);
-                        unpin = (cache->cached == BTRFS_CACHE_FINISHED);
-                        if (likely(unpin)) {
-                                cache->pinned -= len;
-                                cache->space_info->bytes_pinned -= len;
-                                fs_info->total_pinned -= len;
-                        }
-                        spin_unlock(&cache->lock);
-                        spin_unlock(&cache->space_info->lock);
+        spin_lock(&cache->space_info->lock);
+        spin_lock(&cache->lock);
+        cache->pinned += num_bytes;
+        cache->space_info->bytes_pinned += num_bytes;
+        if (reserved) {
+                cache->reserved -= num_bytes;
+                cache->space_info->bytes_reserved -= num_bytes;
+        }
+        spin_unlock(&cache->lock);
+        spin_unlock(&cache->space_info->lock);
 
-                        if (likely(unpin))
-                                clear_extent_dirty(&fs_info->pinned_extents,
-                                                   bytenr, bytenr + len -1,
-                                                   GFP_NOFS);
-                        else
-                                cache_block_group(cache);
+        btrfs_put_block_group(cache);
 
-                        if (unpin)
-                                btrfs_add_free_space(cache, bytenr, len);
-                }
-                btrfs_put_block_group(cache);
-                bytenr += len;
-                num -= len;
+        set_extent_dirty(fs_info->pinned_extents,
+                         bytenr, bytenr + num_bytes - 1, GFP_NOFS);
+        return 0;
+}
+
+static int update_reserved_extents(struct btrfs_block_group_cache *cache,
+                                   u64 num_bytes, int reserve)
+{
+        spin_lock(&cache->space_info->lock);
+        spin_lock(&cache->lock);
+        if (reserve) {
+                cache->reserved += num_bytes;
+                cache->space_info->bytes_reserved += num_bytes;
+        } else {
+                cache->reserved -= num_bytes;
+                cache->space_info->bytes_reserved -= num_bytes;
         }
+        spin_unlock(&cache->lock);
+        spin_unlock(&cache->space_info->lock);
         return 0;
 }
 
-static int update_reserved_extents(struct btrfs_root *root,
-                                   u64 bytenr, u64 num, int reserve)
+int btrfs_prepare_extent_commit(struct btrfs_trans_handle *trans,
+                                struct btrfs_root *root)
 {
-        u64 len;
-        struct btrfs_block_group_cache *cache;
         struct btrfs_fs_info *fs_info = root->fs_info;
+        struct btrfs_caching_control *next;
+        struct btrfs_caching_control *caching_ctl;
+        struct btrfs_block_group_cache *cache;
 
-        while (num > 0) {
-                cache = btrfs_lookup_block_group(fs_info, bytenr);
-                BUG_ON(!cache);
-                len = min(num, cache->key.offset -
-                          (bytenr - cache->key.objectid));
+        down_write(&fs_info->extent_commit_sem);
 
-                spin_lock(&cache->space_info->lock);
-                spin_lock(&cache->lock);
-                if (reserve) {
-                        cache->reserved += len;
-                        cache->space_info->bytes_reserved += len;
+        list_for_each_entry_safe(caching_ctl, next,
+                                 &fs_info->caching_block_groups, list) {
+                cache = caching_ctl->block_group;
+                if (block_group_cache_done(cache)) {
+                        cache->last_byte_to_unpin = (u64)-1;
+                        list_del_init(&caching_ctl->list);
+                        put_caching_control(caching_ctl);
                 } else {
-                        cache->reserved -= len;
-                        cache->space_info->bytes_reserved -= len;
+                        cache->last_byte_to_unpin = caching_ctl->progress;
                 }
-                spin_unlock(&cache->lock);
-                spin_unlock(&cache->space_info->lock);
-                btrfs_put_block_group(cache);
-                bytenr += len;
-                num -= len;
         }
+
+        if (fs_info->pinned_extents == &fs_info->freed_extents[0])
+                fs_info->pinned_extents = &fs_info->freed_extents[1];
+        else
+                fs_info->pinned_extents = &fs_info->freed_extents[0];
+
+        up_write(&fs_info->extent_commit_sem);
         return 0;
 }
 
-int btrfs_copy_pinned(struct btrfs_root *root, struct extent_io_tree *copy)
+static int unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
 {
-        u64 last = 0;
-        u64 start;
-        u64 end;
-        struct extent_io_tree *pinned_extents = &root->fs_info->pinned_extents;
-        int ret;
+        struct btrfs_fs_info *fs_info = root->fs_info;
+        struct btrfs_block_group_cache *cache = NULL;
+        u64 len;
 
-        while (1) {
-                ret = find_first_extent_bit(pinned_extents, last,
-                                            &start, &end, EXTENT_DIRTY);
-                if (ret)
-                        break;
+        while (start <= end) {
+                if (!cache ||
+                    start >= cache->key.objectid + cache->key.offset) {
+                        if (cache)
+                                btrfs_put_block_group(cache);
+                        cache = btrfs_lookup_block_group(fs_info, start);
+                        BUG_ON(!cache);
+                }
+
+                len = cache->key.objectid + cache->key.offset - start;
+                len = min(len, end + 1 - start);
+
+                if (start < cache->last_byte_to_unpin) {
+                        len = min(len, cache->last_byte_to_unpin - start);
+                        btrfs_add_free_space(cache, start, len);
+                }
+
+                spin_lock(&cache->space_info->lock);
+                spin_lock(&cache->lock);
+                cache->pinned -= len;
+                cache->space_info->bytes_pinned -= len;
+                spin_unlock(&cache->lock);
+                spin_unlock(&cache->space_info->lock);
 
-                set_extent_dirty(copy, start, end, GFP_NOFS);
-                last = end + 1;
+                start += len;
         }
+
+        if (cache)
+                btrfs_put_block_group(cache);
         return 0;
 }
 
 int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
-                               struct btrfs_root *root,
-                               struct extent_io_tree *unpin)
+                               struct btrfs_root *root)
 {
+        struct btrfs_fs_info *fs_info = root->fs_info;
+        struct extent_io_tree *unpin;
         u64 start;
         u64 end;
         int ret;
 
+        if (fs_info->pinned_extents == &fs_info->freed_extents[0])
+                unpin = &fs_info->freed_extents[1];
+        else
+                unpin = &fs_info->freed_extents[0];
+
         while (1) {
                 ret = find_first_extent_bit(unpin, 0, &start, &end,
                                             EXTENT_DIRTY);
@@ -3185,10 +3265,8 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
 
                 ret = btrfs_discard_extent(root, start, end + 1 - start);
 
-                /* unlocks the pinned mutex */
-                btrfs_update_pinned_extents(root, start, end + 1 - start, 0);
                 clear_extent_dirty(unpin, start, end, GFP_NOFS);
-
+                unpin_extent_range(root, start, end);
                 cond_resched();
         }
 
@@ -3198,7 +3276,8 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
 static int pin_down_bytes(struct btrfs_trans_handle *trans,
                           struct btrfs_root *root,
                           struct btrfs_path *path,
-                          u64 bytenr, u64 num_bytes, int is_data,
+                          u64 bytenr, u64 num_bytes,
+                          int is_data, int reserved,
                           struct extent_buffer **must_clean)
 {
         int err = 0;
@@ -3230,15 +3309,15 @@ static int pin_down_bytes(struct btrfs_trans_handle *trans,
         }
         free_extent_buffer(buf);
 pinit:
-        btrfs_set_path_blocking(path);
+        if (path)
+                btrfs_set_path_blocking(path);
         /* unlocks the pinned mutex */
-        btrfs_update_pinned_extents(root, bytenr, num_bytes, 1);
+        btrfs_pin_extent(root, bytenr, num_bytes, reserved);
 
         BUG_ON(err < 0);
         return 0;
 }
 
-
 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
                                 struct btrfs_root *root,
                                 u64 bytenr, u64 num_bytes, u64 parent,
@@ -3412,7 +3491,7 @@ static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
                 }
 
                 ret = pin_down_bytes(trans, root, path, bytenr,
-                                     num_bytes, is_data, &must_clean);
+                                     num_bytes, is_data, 0, &must_clean);
                 if (ret > 0)
                         mark_free = 1;
                 BUG_ON(ret < 0);
@@ -3543,8 +3622,7 @@ int btrfs_free_extent(struct btrfs_trans_handle *trans,
         if (root_objectid == BTRFS_TREE_LOG_OBJECTID) {
                 WARN_ON(owner >= BTRFS_FIRST_FREE_OBJECTID);
                 /* unlocks the pinned mutex */
-                btrfs_update_pinned_extents(root, bytenr, num_bytes, 1);
-                update_reserved_extents(root, bytenr, num_bytes, 0);
+                btrfs_pin_extent(root, bytenr, num_bytes, 1);
                 ret = 0;
         } else if (owner < BTRFS_FIRST_FREE_OBJECTID) {
                 ret = btrfs_add_delayed_tree_ref(trans, bytenr, num_bytes,
@@ -3584,19 +3662,33 @@ static noinline int
 wait_block_group_cache_progress(struct btrfs_block_group_cache *cache,
                                 u64 num_bytes)
 {
+        struct btrfs_caching_control *caching_ctl;
         DEFINE_WAIT(wait);
 
-        prepare_to_wait(&cache->caching_q, &wait, TASK_UNINTERRUPTIBLE);
-
-        if (block_group_cache_done(cache)) {
-                finish_wait(&cache->caching_q, &wait);
+        caching_ctl = get_caching_control(cache);
+        if (!caching_ctl)
                 return 0;
-        }
-        schedule();
-        finish_wait(&cache->caching_q, &wait);
 
-        wait_event(cache->caching_q, block_group_cache_done(cache) ||
+        wait_event(caching_ctl->wait, block_group_cache_done(cache) ||
                    (cache->free_space >= num_bytes));
+
+        put_caching_control(caching_ctl);
+        return 0;
+}
+
+static noinline int
+wait_block_group_cache_done(struct btrfs_block_group_cache *cache)
+{
+        struct btrfs_caching_control *caching_ctl;
+        DEFINE_WAIT(wait);
+
+        caching_ctl = get_caching_control(cache);
+        if (!caching_ctl)
+                return 0;
+
+        wait_event(caching_ctl->wait, block_group_cache_done(cache));
+
+        put_caching_control(caching_ctl);
         return 0;
 }
 
@@ -3880,6 +3972,8 @@ checks:
                                              search_start - offset);
                 BUG_ON(offset > search_start);
 
+                update_reserved_extents(block_group, num_bytes, 1);
+
                 /* we are all good, lets return */
                 break;
 loop:
@@ -3972,12 +4066,12 @@ static void dump_space_info(struct btrfs_space_info *info, u64 bytes)
         up_read(&info->groups_sem);
 }
 
-static int __btrfs_reserve_extent(struct btrfs_trans_handle *trans,
-                                  struct btrfs_root *root,
-                                  u64 num_bytes, u64 min_alloc_size,
-                                  u64 empty_size, u64 hint_byte,
-                                  u64 search_end, struct btrfs_key *ins,
-                                  u64 data)
+int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
+                         struct btrfs_root *root,
+                         u64 num_bytes, u64 min_alloc_size,
+                         u64 empty_size, u64 hint_byte,
+                         u64 search_end, struct btrfs_key *ins,
+                         u64 data)
 {
         int ret;
         u64 search_start = 0;
@@ -4043,25 +4137,8 @@ int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
         ret = btrfs_discard_extent(root, start, len);
 
         btrfs_add_free_space(cache, start, len);
+        update_reserved_extents(cache, len, 0);
         btrfs_put_block_group(cache);
-        update_reserved_extents(root, start, len, 0);
-
-        return ret;
-}
-
-int btrfs_reserve_extent(struct btrfs_trans_handle *trans,
-                                  struct btrfs_root *root,
-                                  u64 num_bytes, u64 min_alloc_size,
-                                  u64 empty_size, u64 hint_byte,
-                                  u64 search_end, struct btrfs_key *ins,
-                                  u64 data)
-{
-        int ret;
-        ret = __btrfs_reserve_extent(trans, root, num_bytes, min_alloc_size,
-                                     empty_size, hint_byte, search_end, ins,
-                                     data);
-        if (!ret)
-                update_reserved_extents(root, ins->objectid, ins->offset, 1);
 
         return ret;
 }
@@ -4222,15 +4299,46 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
 {
         int ret;
         struct btrfs_block_group_cache *block_group;
+        struct btrfs_caching_control *caching_ctl;
+        u64 start = ins->objectid;
+        u64 num_bytes = ins->offset;
 
         block_group = btrfs_lookup_block_group(root->fs_info, ins->objectid);
         cache_block_group(block_group);
-        wait_event(block_group->caching_q,
-                   block_group_cache_done(block_group));
+        caching_ctl = get_caching_control(block_group);
 
-        ret = btrfs_remove_free_space(block_group, ins->objectid,
-                                      ins->offset);
-        BUG_ON(ret);
+        if (!caching_ctl) {
+                BUG_ON(!block_group_cache_done(block_group));
+                ret = btrfs_remove_free_space(block_group, start, num_bytes);
+                BUG_ON(ret);
+        } else {
+                mutex_lock(&caching_ctl->mutex);
+
+                if (start >= caching_ctl->progress) {
+                        ret = add_excluded_extent(root, start, num_bytes);
+                        BUG_ON(ret);
+                } else if (start + num_bytes <= caching_ctl->progress) {
+                        ret = btrfs_remove_free_space(block_group,
+                                                      start, num_bytes);
+                        BUG_ON(ret);
+                } else {
+                        num_bytes = caching_ctl->progress - start;
+                        ret = btrfs_remove_free_space(block_group,
+                                                      start, num_bytes);
+                        BUG_ON(ret);
+
+                        start = caching_ctl->progress;
+                        num_bytes = ins->objectid + ins->offset -
+                                    caching_ctl->progress;
+                        ret = add_excluded_extent(root, start, num_bytes);
+                        BUG_ON(ret);
+                }
+
+                mutex_unlock(&caching_ctl->mutex);
+                put_caching_control(caching_ctl);
+        }
+
+        update_reserved_extents(block_group, ins->offset, 1);
         btrfs_put_block_group(block_group);
         ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
                                          0, owner, offset, ins, 1);
@@ -4254,9 +4362,9 @@ static int alloc_tree_block(struct btrfs_trans_handle *trans,
         int ret;
         u64 flags = 0;
 
-        ret = __btrfs_reserve_extent(trans, root, num_bytes, num_bytes,
-                                     empty_size, hint_byte, search_end,
-                                     ins, 0);
+        ret = btrfs_reserve_extent(trans, root, num_bytes, num_bytes,
+                                   empty_size, hint_byte, search_end,
+                                   ins, 0);
         if (ret)
                 return ret;
 
@@ -4267,7 +4375,6 @@ static int alloc_tree_block(struct btrfs_trans_handle *trans,
         } else
                 BUG_ON(parent > 0);
 
-        update_reserved_extents(root, ins->objectid, ins->offset, 1);
         if (root_objectid != BTRFS_TREE_LOG_OBJECTID) {
                 struct btrfs_delayed_extent_op *extent_op;
                 extent_op = kmalloc(sizeof(*extent_op), GFP_NOFS);
@@ -7164,8 +7271,18 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
 {
         struct btrfs_block_group_cache *block_group;
         struct btrfs_space_info *space_info;
+        struct btrfs_caching_control *caching_ctl;
         struct rb_node *n;
 
+        down_write(&info->extent_commit_sem);
+        while (!list_empty(&info->caching_block_groups)) {
+                caching_ctl = list_entry(info->caching_block_groups.next,
+                                         struct btrfs_caching_control, list);
+                list_del(&caching_ctl->list);
+                put_caching_control(caching_ctl);
+        }
+        up_write(&info->extent_commit_sem);
+
         spin_lock(&info->block_group_cache_lock);
         while ((n = rb_last(&info->block_group_cache_tree)) != NULL) {
                 block_group = rb_entry(n, struct btrfs_block_group_cache,
@@ -7179,8 +7296,7 @@ int btrfs_free_block_groups(struct btrfs_fs_info *info)
                 up_write(&block_group->space_info->groups_sem);
 
                 if (block_group->cached == BTRFS_CACHE_STARTED)
-                        wait_event(block_group->caching_q,
-                                   block_group_cache_done(block_group));
+                        wait_block_group_cache_done(block_group);
 
                 btrfs_remove_free_space_cache(block_group);
 
@@ -7250,7 +7366,6 @@ int btrfs_read_block_groups(struct btrfs_root *root)
                 spin_lock_init(&cache->lock);
                 spin_lock_init(&cache->tree_lock);
                 cache->fs_info = info;
-                init_waitqueue_head(&cache->caching_q);
                 INIT_LIST_HEAD(&cache->list);
                 INIT_LIST_HEAD(&cache->cluster_list);
 
@@ -7272,8 +7387,6 @@ int btrfs_read_block_groups(struct btrfs_root *root)
                 cache->flags = btrfs_block_group_flags(&cache->item);
                 cache->sectorsize = root->sectorsize;
 
-                remove_sb_from_cache(root, cache);
-
                 /*
                  * check for two cases, either we are full, and therefore
                  * don't need to bother with the caching work since we won't
@@ -7282,13 +7395,17 @@ int btrfs_read_block_groups(struct btrfs_root *root)
                  * time, particularly in the full case.
                  */
                 if (found_key.offset == btrfs_block_group_used(&cache->item)) {
+                        cache->last_byte_to_unpin = (u64)-1;
                         cache->cached = BTRFS_CACHE_FINISHED;
                 } else if (btrfs_block_group_used(&cache->item) == 0) {
+                        exclude_super_stripes(root, cache);
+                        cache->last_byte_to_unpin = (u64)-1;
                         cache->cached = BTRFS_CACHE_FINISHED;
                         add_new_free_space(cache, root->fs_info,
                                            found_key.objectid,
                                            found_key.objectid +
                                            found_key.offset);
+                        free_excluded_extents(root, cache);
                 }
 
                 ret = update_space_info(info, cache->flags, found_key.offset,
@@ -7345,7 +7462,6 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
         atomic_set(&cache->count, 1);
         spin_lock_init(&cache->lock);
         spin_lock_init(&cache->tree_lock);
-        init_waitqueue_head(&cache->caching_q);
         INIT_LIST_HEAD(&cache->list);
         INIT_LIST_HEAD(&cache->cluster_list);
 
@@ -7354,12 +7470,15 @@ int btrfs_make_block_group(struct btrfs_trans_handle *trans,
         cache->flags = type;
         btrfs_set_block_group_flags(&cache->item, type);
 
+        cache->last_byte_to_unpin = (u64)-1;
         cache->cached = BTRFS_CACHE_FINISHED;
-        remove_sb_from_cache(root, cache);
+        exclude_super_stripes(root, cache);
 
         add_new_free_space(cache, root->fs_info, chunk_offset,
                            chunk_offset + size);
 
+        free_excluded_extents(root, cache);
+
         ret = update_space_info(root->fs_info, cache->flags, size, bytes_used,
                                 &cache->space_info);
         BUG_ON(ret);
@@ -7428,8 +7547,7 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
         up_write(&block_group->space_info->groups_sem);
 
         if (block_group->cached == BTRFS_CACHE_STARTED)
-                wait_event(block_group->caching_q,
-                           block_group_cache_done(block_group));
+                wait_block_group_cache_done(block_group);
 
         btrfs_remove_free_space_cache(block_group);
 
diff --git a/fs/btrfs/transaction.c b/fs/btrfs/transaction.c
index cdbb5022da52..6ed6186f51cd 100644
--- a/fs/btrfs/transaction.c
+++ b/fs/btrfs/transaction.c
@@ -874,7 +874,6 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
         unsigned long timeout = 1;
         struct btrfs_transaction *cur_trans;
         struct btrfs_transaction *prev_trans = NULL;
-        struct extent_io_tree *pinned_copy;
         DEFINE_WAIT(wait);
         int ret;
         int should_grow = 0;
@@ -915,13 +914,6 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
                 return 0;
         }
 
-        pinned_copy = kmalloc(sizeof(*pinned_copy), GFP_NOFS);
-        if (!pinned_copy)
-                return -ENOMEM;
-
-        extent_io_tree_init(pinned_copy,
-                             root->fs_info->btree_inode->i_mapping, GFP_NOFS);
-
         trans->transaction->in_commit = 1;
         trans->transaction->blocked = 1;
         if (cur_trans->list.prev != &root->fs_info->trans_list) {
@@ -1019,6 +1011,8 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
         ret = commit_cowonly_roots(trans, root);
         BUG_ON(ret);
 
+        btrfs_prepare_extent_commit(trans, root);
+
         cur_trans = root->fs_info->running_transaction;
         spin_lock(&root->fs_info->new_trans_lock);
         root->fs_info->running_transaction = NULL;
@@ -1042,8 +1036,6 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
         memcpy(&root->fs_info->super_for_commit, &root->fs_info->super_copy,
                sizeof(root->fs_info->super_copy));
 
-        btrfs_copy_pinned(root, pinned_copy);
-
         trans->transaction->blocked = 0;
 
         wake_up(&root->fs_info->transaction_wait);
@@ -1059,8 +1051,7 @@ int btrfs_commit_transaction(struct btrfs_trans_handle *trans,
          */
         mutex_unlock(&root->fs_info->tree_log_mutex);
 
-        btrfs_finish_extent_commit(trans, root, pinned_copy);
-        kfree(pinned_copy);
+        btrfs_finish_extent_commit(trans, root);
 
         /* do the directory inserts of any pending snapshot creations */
         finish_pending_snapshots(trans, root->fs_info);
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index 8661a7381b39..f4a7b62f9bea 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -263,8 +263,8 @@ static int process_one_buffer(struct btrfs_root *log,
                               struct walk_control *wc, u64 gen)
 {
         if (wc->pin)
-                btrfs_update_pinned_extents(log->fs_info->extent_root,
-                                            eb->start, eb->len, 1);
+                btrfs_pin_extent(log->fs_info->extent_root,
+                                 eb->start, eb->len, 0);
 
         if (btrfs_buffer_uptodate(eb, gen)) {
                 if (wc->write)