diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c index 7af618dcf2c09f0e7a217e850ad1c84fdd4a7b22..ff6bbfd75cf7b4f0788fd5380b35461ea54615f3 100644 --- a/fs/btrfs/extent-tree.c +++ b/fs/btrfs/extent-tree.c @@ -5646,6 +5646,7 @@ use_block_rsv(struct btrfs_trans_handle *trans, struct btrfs_root *root, u32 blocksize) { struct btrfs_block_rsv *block_rsv; + struct btrfs_block_rsv *global_rsv = &root->fs_info->global_block_rsv; int ret; block_rsv = get_block_rsv(trans, root); @@ -5653,14 +5654,39 @@ use_block_rsv(struct btrfs_trans_handle *trans, if (block_rsv->size == 0) { ret = reserve_metadata_bytes(trans, root, block_rsv, blocksize, 0); - if (ret) + /* + * If we couldn't reserve metadata bytes try and use some from + * the global reserve. + */ + if (ret && block_rsv != global_rsv) { + ret = block_rsv_use_bytes(global_rsv, blocksize); + if (!ret) + return global_rsv; + return ERR_PTR(ret); + } else if (ret) { return ERR_PTR(ret); + } return block_rsv; } ret = block_rsv_use_bytes(block_rsv, blocksize); if (!ret) return block_rsv; + if (ret) { + WARN_ON(1); + ret = reserve_metadata_bytes(trans, root, block_rsv, blocksize, + 0); + if (!ret) { + spin_lock(&block_rsv->lock); + block_rsv->size += blocksize; + spin_unlock(&block_rsv->lock); + return block_rsv; + } else if (ret && block_rsv != global_rsv) { + ret = block_rsv_use_bytes(global_rsv, blocksize); + if (!ret) + return global_rsv; + } + } return ERR_PTR(-ENOSPC); }