diff options
Diffstat (limited to 'fs/btrfs/delayed-ref.c')
-rw-r--r-- | fs/btrfs/delayed-ref.c | 46 |
1 files changed, 35 insertions, 11 deletions
diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c index 6a13cf00218b..9fe4ccca50a0 100644 --- a/fs/btrfs/delayed-ref.c +++ b/fs/btrfs/delayed-ref.c @@ -103,24 +103,17 @@ void btrfs_update_delayed_refs_rsv(struct btrfs_trans_handle *trans) * Transfer bytes to our delayed refs rsv. * * @fs_info: the filesystem - * @src: source block rsv to transfer from * @num_bytes: number of bytes to transfer * - * This transfers up to the num_bytes amount from the src rsv to the + * This transfers up to the num_bytes amount, previously reserved, to the * delayed_refs_rsv. Any extra bytes are returned to the space info. */ void btrfs_migrate_to_delayed_refs_rsv(struct btrfs_fs_info *fs_info, - struct btrfs_block_rsv *src, u64 num_bytes) { struct btrfs_block_rsv *delayed_refs_rsv = &fs_info->delayed_refs_rsv; u64 to_free = 0; - spin_lock(&src->lock); - src->reserved -= num_bytes; - src->size -= num_bytes; - spin_unlock(&src->lock); - spin_lock(&delayed_refs_rsv->lock); if (delayed_refs_rsv->size > delayed_refs_rsv->reserved) { u64 delta = delayed_refs_rsv->size - @@ -163,6 +156,8 @@ int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info, struct btrfs_block_rsv *block_rsv = &fs_info->delayed_refs_rsv; u64 limit = btrfs_calc_delayed_ref_bytes(fs_info, 1); u64 num_bytes = 0; + u64 refilled_bytes; + u64 to_free; int ret = -ENOSPC; spin_lock(&block_rsv->lock); @@ -178,9 +173,38 @@ int btrfs_delayed_refs_rsv_refill(struct btrfs_fs_info *fs_info, ret = btrfs_reserve_metadata_bytes(fs_info, block_rsv, num_bytes, flush); if (ret) return ret; - btrfs_block_rsv_add_bytes(block_rsv, num_bytes, false); - trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv", - 0, num_bytes, 1); + + /* + * We may have raced with someone else, so check again if we the block + * reserve is still not full and release any excess space. + */ + spin_lock(&block_rsv->lock); + if (block_rsv->reserved < block_rsv->size) { + u64 needed = block_rsv->size - block_rsv->reserved; + + if (num_bytes >= needed) { + block_rsv->reserved += needed; + block_rsv->full = true; + to_free = num_bytes - needed; + refilled_bytes = needed; + } else { + block_rsv->reserved += num_bytes; + to_free = 0; + refilled_bytes = num_bytes; + } + } else { + to_free = num_bytes; + refilled_bytes = 0; + } + spin_unlock(&block_rsv->lock); + + if (to_free > 0) + btrfs_space_info_free_bytes_may_use(fs_info, block_rsv->space_info, + to_free); + + if (refilled_bytes > 0) + trace_btrfs_space_reservation(fs_info, "delayed_refs_rsv", 0, + refilled_bytes, 1); return 0; } |