Merge branch 'fixes' of git://git.kernel.org/pub/scm/linux/kernel/git/jejb/parisc-2.6
[pandora-kernel.git] / fs / btrfs / extent-tree.c
index 7b3089b..cd52f7f 100644 (file)
 #include "locking.h"
 #include "free-space-cache.h"
 
+/* control flags for do_chunk_alloc's force field
+ * CHUNK_ALLOC_NO_FORCE means to only allocate a chunk
+ * if we really need one.
+ *
+ * CHUNK_ALLOC_FORCE means it must try to allocate one
+ *
+ * CHUNK_ALLOC_LIMITED means to only try and allocate one
+ * if we have very few chunks already allocated.  This is
+ * used as part of the clustering code to help make sure
+ * we have a good pool of storage to cluster in, without
+ * filling the FS with empty chunks
+ *
+ */
+enum {
+       CHUNK_ALLOC_NO_FORCE = 0,
+       CHUNK_ALLOC_FORCE = 1,
+       CHUNK_ALLOC_LIMITED = 2,
+};
+
 static int update_block_group(struct btrfs_trans_handle *trans,
                              struct btrfs_root *root,
                              u64 bytenr, u64 num_bytes, int alloc);
-static int update_reserved_bytes(struct btrfs_block_group_cache *cache,
-                                u64 num_bytes, int reserve, int sinfo);
 static int __btrfs_free_extent(struct btrfs_trans_handle *trans,
                                struct btrfs_root *root,
                                u64 bytenr, u64 num_bytes, u64 parent,
@@ -442,7 +459,7 @@ static int cache_block_group(struct btrfs_block_group_cache *cache,
         * allocate blocks for the tree root we can't do the fast caching since
         * we likely hold important locks.
         */
-       if (!trans->transaction->in_commit &&
+       if (trans && (!trans->transaction->in_commit) &&
            (root && root != root->fs_info->tree_root)) {
                spin_lock(&cache->lock);
                if (cache->cached != BTRFS_CACHE_NO) {
@@ -471,7 +488,7 @@ static int cache_block_group(struct btrfs_block_group_cache *cache,
        if (load_cache_only)
                return 0;
 
-       caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_KERNEL);
+       caching_ctl = kzalloc(sizeof(*caching_ctl), GFP_NOFS);
        BUG_ON(!caching_ctl);
 
        INIT_LIST_HEAD(&caching_ctl->list);
@@ -1740,39 +1757,45 @@ static int remove_extent_backref(struct btrfs_trans_handle *trans,
        return ret;
 }
 
-static void btrfs_issue_discard(struct block_device *bdev,
+static int btrfs_issue_discard(struct block_device *bdev,
                                u64 start, u64 len)
 {
-       blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_KERNEL, 0);
+       return blkdev_issue_discard(bdev, start >> 9, len >> 9, GFP_NOFS, 0);
 }
 
 static int btrfs_discard_extent(struct btrfs_root *root, u64 bytenr,
-                               u64 num_bytes)
+                               u64 num_bytes, u64 *actual_bytes)
 {
        int ret;
-       u64 map_length = num_bytes;
+       u64 discarded_bytes = 0;
        struct btrfs_multi_bio *multi = NULL;
 
-       if (!btrfs_test_opt(root, DISCARD))
-               return 0;
 
        /* 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);
+       ret = btrfs_map_block(&root->fs_info->mapping_tree, REQ_DISCARD,
+                             bytenr, &num_bytes, &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);
+                       ret = btrfs_issue_discard(stripe->dev->bdev,
+                                                 stripe->physical,
+                                                 stripe->length);
+                       if (!ret)
+                               discarded_bytes += stripe->length;
+                       else if (ret != -EOPNOTSUPP)
+                               break;
                }
                kfree(multi);
        }
+       if (discarded_bytes && ret == -EOPNOTSUPP)
+               ret = 0;
+
+       if (actual_bytes)
+               *actual_bytes = discarded_bytes;
+
 
        return ret;
 }
@@ -3015,7 +3038,8 @@ static int update_space_info(struct btrfs_fs_info *info, u64 flags,
        found->bytes_readonly = 0;
        found->bytes_may_use = 0;
        found->full = 0;
-       found->force_alloc = 0;
+       found->force_alloc = CHUNK_ALLOC_NO_FORCE;
+       found->chunk_alloc = 0;
        *space_info = found;
        list_add_rcu(&found->list, &info->space_info);
        atomic_set(&found->caching_threads, 0);
@@ -3146,7 +3170,7 @@ again:
                if (!data_sinfo->full && alloc_chunk) {
                        u64 alloc_target;
 
-                       data_sinfo->force_alloc = 1;
+                       data_sinfo->force_alloc = CHUNK_ALLOC_FORCE;
                        spin_unlock(&data_sinfo->lock);
 alloc:
                        alloc_target = btrfs_get_alloc_profile(root, 1);
@@ -3156,7 +3180,8 @@ alloc:
 
                        ret = do_chunk_alloc(trans, root->fs_info->extent_root,
                                             bytes + 2 * 1024 * 1024,
-                                            alloc_target, 0);
+                                            alloc_target,
+                                            CHUNK_ALLOC_NO_FORCE);
                        btrfs_end_transaction(trans, root);
                        if (ret < 0) {
                                if (ret != -ENOSPC)
@@ -3235,31 +3260,56 @@ static void force_metadata_allocation(struct btrfs_fs_info *info)
        rcu_read_lock();
        list_for_each_entry_rcu(found, head, list) {
                if (found->flags & BTRFS_BLOCK_GROUP_METADATA)
-                       found->force_alloc = 1;
+                       found->force_alloc = CHUNK_ALLOC_FORCE;
        }
        rcu_read_unlock();
 }
 
 static int should_alloc_chunk(struct btrfs_root *root,
-                             struct btrfs_space_info *sinfo, u64 alloc_bytes)
+                             struct btrfs_space_info *sinfo, u64 alloc_bytes,
+                             int force)
 {
        u64 num_bytes = sinfo->total_bytes - sinfo->bytes_readonly;
+       u64 num_allocated = sinfo->bytes_used + sinfo->bytes_reserved;
        u64 thresh;
 
-       if (sinfo->bytes_used + sinfo->bytes_reserved +
-           alloc_bytes + 256 * 1024 * 1024 < num_bytes)
+       if (force == CHUNK_ALLOC_FORCE)
+               return 1;
+
+       /*
+        * in limited mode, we want to have some free space up to
+        * about 1% of the FS size.
+        */
+       if (force == CHUNK_ALLOC_LIMITED) {
+               thresh = btrfs_super_total_bytes(&root->fs_info->super_copy);
+               thresh = max_t(u64, 64 * 1024 * 1024,
+                              div_factor_fine(thresh, 1));
+
+               if (num_bytes - num_allocated < thresh)
+                       return 1;
+       }
+
+       /*
+        * we have two similar checks here, one based on percentage
+        * and once based on a hard number of 256MB.  The idea
+        * is that if we have a good amount of free
+        * room, don't allocate a chunk.  A good mount is
+        * less than 80% utilized of the chunks we have allocated,
+        * or more than 256MB free
+        */
+       if (num_allocated + alloc_bytes + 256 * 1024 * 1024 < num_bytes)
                return 0;
 
-       if (sinfo->bytes_used + sinfo->bytes_reserved +
-           alloc_bytes < div_factor(num_bytes, 8))
+       if (num_allocated + alloc_bytes < div_factor(num_bytes, 8))
                return 0;
 
        thresh = btrfs_super_total_bytes(&root->fs_info->super_copy);
+
+       /* 256MB or 5% of the FS */
        thresh = max_t(u64, 256 * 1024 * 1024, div_factor_fine(thresh, 5));
 
        if (num_bytes > thresh && sinfo->bytes_used < div_factor(num_bytes, 3))
                return 0;
-
        return 1;
 }
 
@@ -3269,10 +3319,9 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
 {
        struct btrfs_space_info *space_info;
        struct btrfs_fs_info *fs_info = extent_root->fs_info;
+       int wait_for_alloc = 0;
        int ret = 0;
 
-       mutex_lock(&fs_info->chunk_mutex);
-
        flags = btrfs_reduce_alloc_profile(extent_root, flags);
 
        space_info = __find_space_info(extent_root->fs_info, flags);
@@ -3283,21 +3332,40 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
        }
        BUG_ON(!space_info);
 
+again:
        spin_lock(&space_info->lock);
        if (space_info->force_alloc)
-               force = 1;
+               force = space_info->force_alloc;
        if (space_info->full) {
                spin_unlock(&space_info->lock);
-               goto out;
+               return 0;
        }
 
-       if (!force && !should_alloc_chunk(extent_root, space_info,
-                                         alloc_bytes)) {
+       if (!should_alloc_chunk(extent_root, space_info, alloc_bytes, force)) {
                spin_unlock(&space_info->lock);
-               goto out;
+               return 0;
+       } else if (space_info->chunk_alloc) {
+               wait_for_alloc = 1;
+       } else {
+               space_info->chunk_alloc = 1;
        }
+
        spin_unlock(&space_info->lock);
 
+       mutex_lock(&fs_info->chunk_mutex);
+
+       /*
+        * The chunk_mutex is held throughout the entirety of a chunk
+        * allocation, so once we've acquired the chunk_mutex we know that the
+        * other guy is done and we need to recheck and see if we should
+        * allocate.
+        */
+       if (wait_for_alloc) {
+               mutex_unlock(&fs_info->chunk_mutex);
+               wait_for_alloc = 0;
+               goto again;
+       }
+
        /*
         * If we have mixed data/metadata chunks we want to make sure we keep
         * allocating mixed chunks instead of individual chunks.
@@ -3323,9 +3391,10 @@ static int do_chunk_alloc(struct btrfs_trans_handle *trans,
                space_info->full = 1;
        else
                ret = 1;
-       space_info->force_alloc = 0;
+
+       space_info->force_alloc = CHUNK_ALLOC_NO_FORCE;
+       space_info->chunk_alloc = 0;
        spin_unlock(&space_info->lock);
-out:
        mutex_unlock(&extent_root->fs_info->chunk_mutex);
        return ret;
 }
@@ -3996,6 +4065,7 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
        struct btrfs_block_rsv *block_rsv = &root->fs_info->delalloc_block_rsv;
        u64 to_reserve;
        int nr_extents;
+       int reserved_extents;
        int ret;
 
        if (btrfs_transaction_in_commit(root->fs_info))
@@ -4003,25 +4073,24 @@ int btrfs_delalloc_reserve_metadata(struct inode *inode, u64 num_bytes)
 
        num_bytes = ALIGN(num_bytes, root->sectorsize);
 
-       spin_lock(&BTRFS_I(inode)->accounting_lock);
        nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents) + 1;
-       if (nr_extents > BTRFS_I(inode)->reserved_extents) {
-               nr_extents -= BTRFS_I(inode)->reserved_extents;
+       reserved_extents = atomic_read(&BTRFS_I(inode)->reserved_extents);
+
+       if (nr_extents > reserved_extents) {
+               nr_extents -= reserved_extents;
                to_reserve = calc_trans_metadata_size(root, nr_extents);
        } else {
                nr_extents = 0;
                to_reserve = 0;
        }
-       spin_unlock(&BTRFS_I(inode)->accounting_lock);
+
        to_reserve += calc_csum_metadata_size(inode, num_bytes);
        ret = reserve_metadata_bytes(NULL, root, block_rsv, to_reserve, 1);
        if (ret)
                return ret;
 
-       spin_lock(&BTRFS_I(inode)->accounting_lock);
-       BTRFS_I(inode)->reserved_extents += nr_extents;
+       atomic_add(nr_extents, &BTRFS_I(inode)->reserved_extents);
        atomic_inc(&BTRFS_I(inode)->outstanding_extents);
-       spin_unlock(&BTRFS_I(inode)->accounting_lock);
 
        block_rsv_add_bytes(block_rsv, to_reserve, 1);
 
@@ -4036,20 +4105,30 @@ void btrfs_delalloc_release_metadata(struct inode *inode, u64 num_bytes)
        struct btrfs_root *root = BTRFS_I(inode)->root;
        u64 to_free;
        int nr_extents;
+       int reserved_extents;
 
        num_bytes = ALIGN(num_bytes, root->sectorsize);
        atomic_dec(&BTRFS_I(inode)->outstanding_extents);
        WARN_ON(atomic_read(&BTRFS_I(inode)->outstanding_extents) < 0);
 
-       spin_lock(&BTRFS_I(inode)->accounting_lock);
-       nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents);
-       if (nr_extents < BTRFS_I(inode)->reserved_extents) {
-               nr_extents = BTRFS_I(inode)->reserved_extents - nr_extents;
-               BTRFS_I(inode)->reserved_extents -= nr_extents;
-       } else {
-               nr_extents = 0;
-       }
-       spin_unlock(&BTRFS_I(inode)->accounting_lock);
+       reserved_extents = atomic_read(&BTRFS_I(inode)->reserved_extents);
+       do {
+               int old, new;
+
+               nr_extents = atomic_read(&BTRFS_I(inode)->outstanding_extents);
+               if (nr_extents >= reserved_extents) {
+                       nr_extents = 0;
+                       break;
+               }
+               old = reserved_extents;
+               nr_extents = reserved_extents - nr_extents;
+               new = reserved_extents - nr_extents;
+               old = atomic_cmpxchg(&BTRFS_I(inode)->reserved_extents,
+                                    reserved_extents, new);
+               if (likely(old == reserved_extents))
+                       break;
+               reserved_extents = old;
+       } while (1);
 
        to_free = calc_csum_metadata_size(inode, num_bytes);
        if (nr_extents > 0)
@@ -4223,8 +4302,8 @@ int btrfs_pin_extent(struct btrfs_root *root,
  * update size of reserved extents. this function may return -EAGAIN
  * if 'reserve' is true or 'sinfo' is false.
  */
-static int update_reserved_bytes(struct btrfs_block_group_cache *cache,
-                                u64 num_bytes, int reserve, int sinfo)
+int btrfs_update_reserved_bytes(struct btrfs_block_group_cache *cache,
+                               u64 num_bytes, int reserve, int sinfo)
 {
        int ret = 0;
        if (sinfo) {
@@ -4363,7 +4442,9 @@ int btrfs_finish_extent_commit(struct btrfs_trans_handle *trans,
                if (ret)
                        break;
 
-               ret = btrfs_discard_extent(root, start, end + 1 - start);
+               if (btrfs_test_opt(root, DISCARD))
+                       ret = btrfs_discard_extent(root, start,
+                                                  end + 1 - start, NULL);
 
                clear_extent_dirty(unpin, start, end, GFP_NOFS);
                unpin_extent_range(root, start, end);
@@ -4704,10 +4785,10 @@ void btrfs_free_tree_block(struct btrfs_trans_handle *trans,
                WARN_ON(test_bit(EXTENT_BUFFER_DIRTY, &buf->bflags));
 
                btrfs_add_free_space(cache, buf->start, buf->len);
-               ret = update_reserved_bytes(cache, buf->len, 0, 0);
+               ret = btrfs_update_reserved_bytes(cache, buf->len, 0, 0);
                if (ret == -EAGAIN) {
                        /* block group became read-only */
-                       update_reserved_bytes(cache, buf->len, 0, 1);
+                       btrfs_update_reserved_bytes(cache, buf->len, 0, 1);
                        goto out;
                }
 
@@ -4744,6 +4825,11 @@ pin:
                }
        }
 out:
+       /*
+        * Deleting the buffer, clear the corrupt flag since it doesn't matter
+        * anymore.
+        */
+       clear_bit(EXTENT_BUFFER_CORRUPT, &buf->bflags);
        btrfs_put_block_group(cache);
 }
 
@@ -5191,7 +5277,7 @@ checks:
                                             search_start - offset);
                BUG_ON(offset > search_start);
 
-               ret = update_reserved_bytes(block_group, num_bytes, 1,
+               ret = btrfs_update_reserved_bytes(block_group, num_bytes, 1,
                                            (data & BTRFS_BLOCK_GROUP_DATA));
                if (ret == -EAGAIN) {
                        btrfs_add_free_space(block_group, offset, num_bytes);
@@ -5282,11 +5368,13 @@ loop:
 
                if (allowed_chunk_alloc) {
                        ret = do_chunk_alloc(trans, root, num_bytes +
-                                            2 * 1024 * 1024, data, 1);
+                                            2 * 1024 * 1024, data,
+                                            CHUNK_ALLOC_LIMITED);
                        allowed_chunk_alloc = 0;
                        done_chunk_alloc = 1;
-               } else if (!done_chunk_alloc) {
-                       space_info->force_alloc = 1;
+               } else if (!done_chunk_alloc &&
+                          space_info->force_alloc == CHUNK_ALLOC_NO_FORCE) {
+                       space_info->force_alloc = CHUNK_ALLOC_LIMITED;
                }
 
                if (loop < LOOP_NO_EMPTY_SIZE) {
@@ -5372,7 +5460,8 @@ again:
         */
        if (empty_size || root->ref_cows)
                ret = do_chunk_alloc(trans, root->fs_info->extent_root,
-                                    num_bytes + 2 * 1024 * 1024, data, 0);
+                                    num_bytes + 2 * 1024 * 1024, data,
+                                    CHUNK_ALLOC_NO_FORCE);
 
        WARN_ON(num_bytes < root->sectorsize);
        ret = find_free_extent(trans, root, num_bytes, empty_size,
@@ -5384,7 +5473,7 @@ again:
                num_bytes = num_bytes & ~(root->sectorsize - 1);
                num_bytes = max(num_bytes, min_alloc_size);
                do_chunk_alloc(trans, root->fs_info->extent_root,
-                              num_bytes, data, 1);
+                              num_bytes, data, CHUNK_ALLOC_FORCE);
                goto again;
        }
        if (ret == -ENOSPC && btrfs_test_opt(root, ENOSPC_DEBUG)) {
@@ -5397,6 +5486,8 @@ again:
                dump_space_info(sinfo, num_bytes, 1);
        }
 
+       trace_btrfs_reserved_extent_alloc(root, ins->objectid, ins->offset);
+
        return ret;
 }
 
@@ -5412,12 +5503,15 @@ int btrfs_free_reserved_extent(struct btrfs_root *root, u64 start, u64 len)
                return -ENOSPC;
        }
 
-       ret = btrfs_discard_extent(root, start, len);
+       if (btrfs_test_opt(root, DISCARD))
+               ret = btrfs_discard_extent(root, start, len, NULL);
 
        btrfs_add_free_space(cache, start, len);
-       update_reserved_bytes(cache, len, 0, 1);
+       btrfs_update_reserved_bytes(cache, len, 0, 1);
        btrfs_put_block_group(cache);
 
+       trace_btrfs_reserved_extent_free(root, start, len);
+
        return ret;
 }
 
@@ -5444,7 +5538,8 @@ static int alloc_reserved_file_extent(struct btrfs_trans_handle *trans,
        size = sizeof(*extent_item) + btrfs_extent_inline_ref_size(type);
 
        path = btrfs_alloc_path();
-       BUG_ON(!path);
+       if (!path)
+               return -ENOMEM;
 
        path->leave_spinning = 1;
        ret = btrfs_insert_empty_item(trans, fs_info->extent_root, path,
@@ -5614,7 +5709,7 @@ int btrfs_alloc_logged_file_extent(struct btrfs_trans_handle *trans,
                put_caching_control(caching_ctl);
        }
 
-       ret = update_reserved_bytes(block_group, ins->offset, 1, 1);
+       ret = btrfs_update_reserved_bytes(block_group, ins->offset, 1, 1);
        BUG_ON(ret);
        btrfs_put_block_group(block_group);
        ret = alloc_reserved_file_extent(trans, root, 0, root_objectid,
@@ -6047,6 +6142,8 @@ static noinline int do_walk_down(struct btrfs_trans_handle *trans,
                if (reada && level == 1)
                        reada_walk_down(trans, root, wc, path);
                next = read_tree_block(root, bytenr, blocksize, generation);
+               if (!next)
+                       return -EIO;
                btrfs_tree_lock(next);
                btrfs_set_lock_blocking(next);
        }
@@ -6438,10 +6535,14 @@ int btrfs_drop_subtree(struct btrfs_trans_handle *trans,
        BUG_ON(root->root_key.objectid != BTRFS_TREE_RELOC_OBJECTID);
 
        path = btrfs_alloc_path();
-       BUG_ON(!path);
+       if (!path)
+               return -ENOMEM;
 
        wc = kzalloc(sizeof(*wc), GFP_NOFS);
-       BUG_ON(!wc);
+       if (!wc) {
+               btrfs_free_path(path);
+               return -ENOMEM;
+       }
 
        btrfs_assert_tree_locked(parent);
        parent_level = btrfs_header_level(parent);
@@ -6899,7 +7000,11 @@ static noinline int get_new_locations(struct inode *reloc_inode,
        }
 
        path = btrfs_alloc_path();
-       BUG_ON(!path);
+       if (!path) {
+               if (exts != *extents)
+                       kfree(exts);
+               return -ENOMEM;
+       }
 
        cur_pos = extent_key->objectid - offset;
        last_byte = extent_key->objectid + extent_key->offset;
@@ -6941,6 +7046,10 @@ static noinline int get_new_locations(struct inode *reloc_inode,
                        struct disk_extent *old = exts;
                        max *= 2;
                        exts = kzalloc(sizeof(*exts) * max, GFP_NOFS);
+                       if (!exts) {
+                               ret = -ENOMEM;
+                               goto out;
+                       }
                        memcpy(exts, old, sizeof(*exts) * nr);
                        if (old != *extents)
                                kfree(old);
@@ -7423,7 +7532,8 @@ static noinline int replace_extents_in_leaf(struct btrfs_trans_handle *trans,
        int ret;
 
        new_extent = kmalloc(sizeof(*new_extent), GFP_NOFS);
-       BUG_ON(!new_extent);
+       if (!new_extent)
+               return -ENOMEM;
 
        ref = btrfs_lookup_leaf_ref(root, leaf->start);
        BUG_ON(!ref);
@@ -7609,7 +7719,8 @@ int btrfs_cleanup_reloc_trees(struct btrfs_root *root)
 
        reloc_root = btrfs_read_fs_root_no_name(root->fs_info, &location);
        BUG_ON(!reloc_root);
-       btrfs_orphan_cleanup(reloc_root);
+       ret = btrfs_orphan_cleanup(reloc_root);
+       BUG_ON(ret);
        return 0;
 }
 
@@ -7627,7 +7738,8 @@ static noinline int init_reloc_tree(struct btrfs_trans_handle *trans,
                return 0;
 
        root_item = kmalloc(sizeof(*root_item), GFP_NOFS);
-       BUG_ON(!root_item);
+       if (!root_item)
+               return -ENOMEM;
 
        ret = btrfs_copy_root(trans, root, root->commit_root,
                              &eb, BTRFS_TREE_RELOC_OBJECTID);
@@ -7653,7 +7765,7 @@ static noinline int init_reloc_tree(struct btrfs_trans_handle *trans,
 
        reloc_root = btrfs_read_fs_root_no_radix(root->fs_info->tree_root,
                                                 &root_key);
-       BUG_ON(!reloc_root);
+       BUG_ON(IS_ERR(reloc_root));
        reloc_root->last_trans = trans->transid;
        reloc_root->commit_root = NULL;
        reloc_root->ref_tree = &root->fs_info->reloc_ref_tree;
@@ -7906,6 +8018,10 @@ static noinline int relocate_one_extent(struct btrfs_root *extent_root,
 
                        eb = read_tree_block(found_root, block_start,
                                             block_size, 0);
+                       if (!eb) {
+                               ret = -EIO;
+                               goto out;
+                       }
                        btrfs_tree_lock(eb);
                        BUG_ON(level != btrfs_header_level(eb));
 
@@ -7943,6 +8059,10 @@ static noinline int relocate_one_extent(struct btrfs_root *extent_root,
                                u64 group_start = group->key.objectid;
                                new_extents = kmalloc(sizeof(*new_extents),
                                                      GFP_NOFS);
+                               if (!new_extents) {
+                                       ret = -ENOMEM;
+                                       goto out;
+                               }
                                nr_extents = 1;
                                ret = get_new_locations(reloc_inode,
                                                        extent_key,
@@ -8061,13 +8181,15 @@ int btrfs_set_block_group_ro(struct btrfs_root *root,
 
        alloc_flags = update_block_group_flags(root, cache->flags);
        if (alloc_flags != cache->flags)
-               do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
+               do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
+                              CHUNK_ALLOC_FORCE);
 
        ret = set_block_group_ro(cache);
        if (!ret)
                goto out;
        alloc_flags = get_alloc_profile(root, cache->space_info->flags);
-       ret = do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
+       ret = do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
+                            CHUNK_ALLOC_FORCE);
        if (ret < 0)
                goto out;
        ret = set_block_group_ro(cache);
@@ -8080,7 +8202,8 @@ int btrfs_force_chunk_alloc(struct btrfs_trans_handle *trans,
                            struct btrfs_root *root, u64 type)
 {
        u64 alloc_flags = get_alloc_profile(root, type);
-       return do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags, 1);
+       return do_chunk_alloc(trans, root, 2 * 1024 * 1024, alloc_flags,
+                             CHUNK_ALLOC_FORCE);
 }
 
 /*
@@ -8621,6 +8744,12 @@ int btrfs_remove_block_group(struct btrfs_trans_handle *trans,
        BUG_ON(!block_group);
        BUG_ON(!block_group->ro);
 
+       /*
+        * Free the reserved super bytes from this block group before
+        * remove it.
+        */
+       free_excluded_extents(root, block_group);
+
        memcpy(&key, &block_group->key, sizeof(key));
        if (block_group->flags & (BTRFS_BLOCK_GROUP_DUP |
                                  BTRFS_BLOCK_GROUP_RAID1 |
@@ -8724,13 +8853,84 @@ out:
        return ret;
 }
 
+int btrfs_init_space_info(struct btrfs_fs_info *fs_info)
+{
+       struct btrfs_space_info *space_info;
+       int ret;
+
+       ret = update_space_info(fs_info, BTRFS_BLOCK_GROUP_SYSTEM, 0, 0,
+                                                                &space_info);
+       if (ret)
+               return ret;
+
+       ret = update_space_info(fs_info, BTRFS_BLOCK_GROUP_METADATA, 0, 0,
+                                                                &space_info);
+       if (ret)
+               return ret;
+
+       ret = update_space_info(fs_info, BTRFS_BLOCK_GROUP_DATA, 0, 0,
+                                                                &space_info);
+       if (ret)
+               return ret;
+
+       return ret;
+}
+
 int btrfs_error_unpin_extent_range(struct btrfs_root *root, u64 start, u64 end)
 {
        return unpin_extent_range(root, start, end);
 }
 
 int btrfs_error_discard_extent(struct btrfs_root *root, u64 bytenr,
-                              u64 num_bytes)
+                              u64 num_bytes, u64 *actual_bytes)
+{
+       return btrfs_discard_extent(root, bytenr, num_bytes, actual_bytes);
+}
+
+int btrfs_trim_fs(struct btrfs_root *root, struct fstrim_range *range)
 {
-       return btrfs_discard_extent(root, bytenr, num_bytes);
+       struct btrfs_fs_info *fs_info = root->fs_info;
+       struct btrfs_block_group_cache *cache = NULL;
+       u64 group_trimmed;
+       u64 start;
+       u64 end;
+       u64 trimmed = 0;
+       int ret = 0;
+
+       cache = btrfs_lookup_block_group(fs_info, range->start);
+
+       while (cache) {
+               if (cache->key.objectid >= (range->start + range->len)) {
+                       btrfs_put_block_group(cache);
+                       break;
+               }
+
+               start = max(range->start, cache->key.objectid);
+               end = min(range->start + range->len,
+                               cache->key.objectid + cache->key.offset);
+
+               if (end - start >= range->minlen) {
+                       if (!block_group_cache_done(cache)) {
+                               ret = cache_block_group(cache, NULL, root, 0);
+                               if (!ret)
+                                       wait_block_group_cache_done(cache);
+                       }
+                       ret = btrfs_trim_block_group(cache,
+                                                    &group_trimmed,
+                                                    start,
+                                                    end,
+                                                    range->minlen);
+
+                       trimmed += group_trimmed;
+                       if (ret) {
+                               btrfs_put_block_group(cache);
+                               break;
+                       }
+               }
+
+               cache = next_block_group(fs_info->tree_root, cache);
+       }
+
+       range->len = trimmed;
+       return ret;
 }