diff options
Diffstat (limited to 'fs/btrfs/delayed-ref.c')
-rw-r--r-- | fs/btrfs/delayed-ref.c | 113 |
1 files changed, 113 insertions, 0 deletions
diff --git a/fs/btrfs/delayed-ref.c b/fs/btrfs/delayed-ref.c index bd9b63b..2f41580 100644 --- a/fs/btrfs/delayed-ref.c +++ b/fs/btrfs/delayed-ref.c @@ -197,6 +197,119 @@ static inline void drop_delayed_ref(struct btrfs_trans_handle *trans, trans->delayed_ref_updates--; } +static bool merge_ref(struct btrfs_trans_handle *trans, + struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_head *head, + struct btrfs_delayed_ref_node *ref, + u64 seq) +{ + struct btrfs_delayed_ref_node *next; + bool done = false; + + next = list_first_entry(&head->ref_list, struct btrfs_delayed_ref_node, + list); + while (!done && &next->list != &head->ref_list) { + int mod; + struct btrfs_delayed_ref_node *next2; + + next2 = list_next_entry(next, list); + + if (next == ref) + goto next; + + if (seq && next->seq >= seq) + goto next; + + if (next->type != ref->type || next->no_quota != ref->no_quota) + goto next; + + if ((ref->type == BTRFS_TREE_BLOCK_REF_KEY || + ref->type == BTRFS_SHARED_BLOCK_REF_KEY) && + comp_tree_refs(btrfs_delayed_node_to_tree_ref(ref), + btrfs_delayed_node_to_tree_ref(next), + ref->type)) + goto next; + if ((ref->type == BTRFS_EXTENT_DATA_REF_KEY || + ref->type == BTRFS_SHARED_DATA_REF_KEY) && + comp_data_refs(btrfs_delayed_node_to_data_ref(ref), + btrfs_delayed_node_to_data_ref(next))) + goto next; + + if (ref->action == next->action) { + mod = next->ref_mod; + } else { + if (ref->ref_mod < next->ref_mod) { + swap(ref, next); + done = true; + } + mod = -next->ref_mod; + } + + drop_delayed_ref(trans, delayed_refs, head, next); + ref->ref_mod += mod; + if (ref->ref_mod == 0) { + drop_delayed_ref(trans, delayed_refs, head, ref); + done = true; + } else { + /* + * Can't have multiples of the same ref on a tree block. + */ + WARN_ON(ref->type == BTRFS_TREE_BLOCK_REF_KEY || + ref->type == BTRFS_SHARED_BLOCK_REF_KEY); + } +next: + next = next2; + } + + return done; +} + +void btrfs_merge_delayed_refs(struct btrfs_trans_handle *trans, + struct btrfs_fs_info *fs_info, + struct btrfs_delayed_ref_root *delayed_refs, + struct btrfs_delayed_ref_head *head) +{ + struct btrfs_delayed_ref_node *ref; + u64 seq = 0; + + assert_spin_locked(&head->lock); + + if (list_empty(&head->ref_list)) + return; + + /* We don't have too many refs to merge for data. */ + if (head->is_data) + return; + + spin_lock(&fs_info->tree_mod_seq_lock); + if (!list_empty(&fs_info->tree_mod_seq_list)) { + struct seq_list *elem; + + elem = list_first_entry(&fs_info->tree_mod_seq_list, + struct seq_list, list); + seq = elem->seq; + } + spin_unlock(&fs_info->tree_mod_seq_lock); + + ref = list_first_entry(&head->ref_list, struct btrfs_delayed_ref_node, + list); + while (&ref->list != &head->ref_list) { + if (seq && ref->seq >= seq) + goto next; + + if (merge_ref(trans, delayed_refs, head, ref, seq)) { + if (list_empty(&head->ref_list)) + break; + ref = list_first_entry(&head->ref_list, + struct btrfs_delayed_ref_node, + list); + continue; + } +next: + ref = list_next_entry(ref, list); + } +} + int btrfs_check_delayed_seq(struct btrfs_fs_info *fs_info, struct btrfs_delayed_ref_root *delayed_refs, u64 seq) |