When running functions that can make changes to the internal trees (e.g. btrfs_search_slot), we check if somebody may be interested in the block we're currently modifying. If so, we record our modification to be able to rewind it later on.
Signed-off-by: Jan Schmidt <[email protected]> --- fs/btrfs/ctree.c | 39 +++++++++++++++++++++++++++++++++++++++ 1 files changed, 39 insertions(+), 0 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 6a7418d..7c2d79c 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -39,6 +39,14 @@ static int balance_node_right(struct btrfs_trans_handle *trans, struct extent_buffer *src_buf); static void del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, int level, int slot); +static void tree_mod_log_free_eb(struct btrfs_fs_info *fs_info, + struct extent_buffer *eb); +struct extent_buffer *read_old_tree_block(struct btrfs_root *root, u64 bytenr, + u32 blocksize, u64 parent_transid, + u64 time_seq); +struct extent_buffer *btrfs_find_old_tree_block(struct btrfs_root *root, + u64 bytenr, u32 blocksize, + u64 time_seq); struct btrfs_path *btrfs_alloc_path(void) { @@ -677,6 +685,9 @@ static void tree_mod_log_free_eb(struct btrfs_fs_info *fs_info, int ret; u32 nritems; + if (btrfs_header_level(eb) == 0) + return; + nritems = btrfs_header_nritems(eb); for (i = nritems - 1; i >= 0; i--) { ret = tree_mod_log_insert_key(fs_info, eb, i, @@ -817,6 +828,12 @@ static noinline int update_ref_for_cow(struct btrfs_trans_handle *trans, ret = btrfs_dec_ref(trans, root, buf, 1, 1); BUG_ON(ret); /* -ENOMEM */ } + /* + * don't log freeing in case we're freeing the root node, this + * is done by tree_mod_log_set_root_pointer later + */ + if (buf != root->node && btrfs_header_level(buf) != 0) + tree_mod_log_free_eb(root->fs_info, buf); clean_tree_block(trans, root, buf); *last_ref = 1; } @@ -914,6 +931,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, parent_start = 0; extent_buffer_get(cow); + tree_mod_log_set_root_pointer(root, cow); rcu_assign_pointer(root->node, cow); btrfs_free_tree_block(trans, root, buf, parent_start, @@ -927,6 +945,8 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, parent_start = 0; WARN_ON(trans->transid != btrfs_header_generation(parent)); + tree_mod_log_insert_key(root->fs_info, parent, parent_slot, + MOD_LOG_KEY_REPLACE); btrfs_set_node_blockptr(parent, parent_slot, cow->start); btrfs_set_node_ptr_generation(parent, parent_slot, @@ -1382,6 +1402,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans, goto enospc; } + tree_mod_log_set_root_pointer(root, child); rcu_assign_pointer(root->node, child); add_root_to_dirty_list(root); @@ -1456,6 +1477,8 @@ static noinline int balance_level(struct btrfs_trans_handle *trans, } else { struct btrfs_disk_key right_key; btrfs_node_key(right, &right_key, 0); + tree_mod_log_set_node_key(root->fs_info, parent, + &right_key, pslot + 1, 0); btrfs_set_node_key(parent, &right_key, pslot + 1); btrfs_mark_buffer_dirty(parent); } @@ -1499,6 +1522,8 @@ static noinline int balance_level(struct btrfs_trans_handle *trans, /* update the parent key to reflect our changes */ struct btrfs_disk_key mid_key; btrfs_node_key(mid, &mid_key, 0); + tree_mod_log_set_node_key(root->fs_info, parent, &mid_key, + pslot, 0); btrfs_set_node_key(parent, &mid_key, pslot); btrfs_mark_buffer_dirty(parent); } @@ -1596,6 +1621,8 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans, struct btrfs_disk_key disk_key; orig_slot += left_nr; btrfs_node_key(mid, &disk_key, 0); + tree_mod_log_set_node_key(root->fs_info, parent, + &disk_key, pslot, 0); btrfs_set_node_key(parent, &disk_key, pslot); btrfs_mark_buffer_dirty(parent); if (btrfs_header_nritems(left) > orig_slot) { @@ -1647,6 +1674,8 @@ static noinline int push_nodes_for_insert(struct btrfs_trans_handle *trans, struct btrfs_disk_key disk_key; btrfs_node_key(right, &disk_key, 0); + tree_mod_log_set_node_key(root->fs_info, parent, + &disk_key, pslot + 1, 0); btrfs_set_node_key(parent, &disk_key, pslot + 1); btrfs_mark_buffer_dirty(parent); @@ -2349,6 +2378,7 @@ static void fixup_low_keys(struct btrfs_trans_handle *trans, if (!path->nodes[i]) break; t = path->nodes[i]; + tree_mod_log_set_node_key(root->fs_info, t, key, tslot, 1); btrfs_set_node_key(t, key, tslot); btrfs_mark_buffer_dirty(path->nodes[i]); if (tslot != 0) @@ -2431,12 +2461,16 @@ static int push_node_left(struct btrfs_trans_handle *trans, } else push_items = min(src_nritems - 8, push_items); + tree_mod_log_eb_copy(root->fs_info, dst, src, dst_nritems, 0, + push_items); copy_extent_buffer(dst, src, btrfs_node_key_ptr_offset(dst_nritems), btrfs_node_key_ptr_offset(0), push_items * sizeof(struct btrfs_key_ptr)); if (push_items < src_nritems) { + tree_mod_log_eb_move(root->fs_info, src, 0, push_items, + src_nritems - push_items); memmove_extent_buffer(src, btrfs_node_key_ptr_offset(0), btrfs_node_key_ptr_offset(push_items), (src_nritems - push_items) * @@ -2490,11 +2524,14 @@ static int balance_node_right(struct btrfs_trans_handle *trans, if (max_push < push_items) push_items = max_push; + tree_mod_log_eb_move(root->fs_info, dst, push_items, 0, dst_nritems); memmove_extent_buffer(dst, btrfs_node_key_ptr_offset(push_items), btrfs_node_key_ptr_offset(0), (dst_nritems) * sizeof(struct btrfs_key_ptr)); + tree_mod_log_eb_copy(root->fs_info, dst, src, 0, + src_nritems - push_items, push_items); copy_extent_buffer(dst, src, btrfs_node_key_ptr_offset(0), btrfs_node_key_ptr_offset(src_nritems - push_items), @@ -2569,6 +2606,7 @@ static noinline int insert_new_root(struct btrfs_trans_handle *trans, btrfs_mark_buffer_dirty(c); old = root->node; + tree_mod_log_set_root_pointer(root, c); rcu_assign_pointer(root->node, c); /* the super has an extra ref to root->node */ @@ -2679,6 +2717,7 @@ static noinline int split_node(struct btrfs_trans_handle *trans, (unsigned long)btrfs_header_chunk_tree_uuid(split), BTRFS_UUID_SIZE); + tree_mod_log_eb_copy(root->fs_info, split, c, 0, mid, c_nritems - mid); copy_extent_buffer(split, c, btrfs_node_key_ptr_offset(0), btrfs_node_key_ptr_offset(mid), -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
