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 <list.bt...@jan-o-sch.net> --- fs/btrfs/ctree.c | 126 ++++++++++++++++++++++++++++++++++-------------------- 1 files changed, 79 insertions(+), 47 deletions(-) diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c index 6420638..724eade 100644 --- a/fs/btrfs/ctree.c +++ b/fs/btrfs/ctree.c @@ -38,7 +38,18 @@ static int balance_node_right(struct btrfs_trans_handle *trans, struct extent_buffer *dst_buf, 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); + struct btrfs_path *path, int level, int slot, + int tree_mod_log); +static inline void set_root_pointer(struct btrfs_root *root, + struct extent_buffer *new_root_node); +static void __log_cleaning(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) { @@ -678,6 +689,9 @@ static void __log_cleaning(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, @@ -818,6 +832,9 @@ 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 */ } + /* the root node will be logged in set_root_pointer later */ + if (buf != root->node && btrfs_header_level(buf) != 0) + __log_cleaning(root->fs_info, buf); clean_tree_block(trans, root, buf); *last_ref = 1; } @@ -915,7 +932,7 @@ static noinline int __btrfs_cow_block(struct btrfs_trans_handle *trans, parent_start = 0; extent_buffer_get(cow); - rcu_assign_pointer(root->node, cow); + set_root_pointer(root, cow); btrfs_free_tree_block(trans, root, buf, parent_start, last_ref); @@ -928,6 +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, @@ -1383,7 +1402,9 @@ static noinline int balance_level(struct btrfs_trans_handle *trans, goto enospc; } - rcu_assign_pointer(root->node, child); + ret = tree_mod_log_insert_key(root->fs_info, mid, 0, + MOD_LOG_KEY_REMOVE); + set_root_pointer(root, child); add_root_to_dirty_list(root); btrfs_tree_unlock(child); @@ -1449,7 +1470,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans, if (btrfs_header_nritems(right) == 0) { clean_tree_block(trans, root, right); btrfs_tree_unlock(right); - del_ptr(trans, root, path, level + 1, pslot + 1); + del_ptr(trans, root, path, level + 1, pslot + 1, 1); root_sub_used(root, right->len); btrfs_free_tree_block(trans, root, right, 0, 1); free_extent_buffer_stale(right); @@ -1457,7 +1478,8 @@ static noinline int balance_level(struct btrfs_trans_handle *trans, } else { struct btrfs_disk_key right_key; btrfs_node_key(right, &right_key, 0); - btrfs_set_node_key(parent, &right_key, pslot + 1); + __set_node_key_log(root->fs_info, parent, + &right_key, pslot + 1, 0); btrfs_mark_buffer_dirty(parent); } } @@ -1491,7 +1513,7 @@ static noinline int balance_level(struct btrfs_trans_handle *trans, if (btrfs_header_nritems(mid) == 0) { clean_tree_block(trans, root, mid); btrfs_tree_unlock(mid); - del_ptr(trans, root, path, level + 1, pslot); + del_ptr(trans, root, path, level + 1, pslot, 1); root_sub_used(root, mid->len); btrfs_free_tree_block(trans, root, mid, 0, 1); free_extent_buffer_stale(mid); @@ -1500,7 +1522,7 @@ 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); - btrfs_set_node_key(parent, &mid_key, pslot); + __set_node_key_log(root->fs_info, parent, &mid_key, pslot, 0); btrfs_mark_buffer_dirty(parent); } @@ -1597,7 +1619,8 @@ 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); - btrfs_set_node_key(parent, &disk_key, pslot); + __set_node_key_log(root->fs_info, parent, &disk_key, + pslot, 0); btrfs_mark_buffer_dirty(parent); if (btrfs_header_nritems(left) > orig_slot) { path->nodes[level] = left; @@ -1648,7 +1671,8 @@ 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); - btrfs_set_node_key(parent, &disk_key, pslot + 1); + __set_node_key_log(root->fs_info, parent, &disk_key, + pslot + 1, 0); btrfs_mark_buffer_dirty(parent); if (btrfs_header_nritems(mid) <= orig_slot) { @@ -2350,7 +2374,7 @@ static void fixup_low_keys(struct btrfs_trans_handle *trans, if (!path->nodes[i]) break; t = path->nodes[i]; - btrfs_set_node_key(t, key, tslot); + __set_node_key_log(root->fs_info, t, key, tslot, 1); btrfs_mark_buffer_dirty(path->nodes[i]); if (tslot != 0) break; @@ -2432,16 +2456,14 @@ static int push_node_left(struct btrfs_trans_handle *trans, } else push_items = min(src_nritems - 8, 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)); + + __copy_extent_buffer_log(root->fs_info, dst, src, dst_nritems, 0, + push_items, sizeof(struct btrfs_key_ptr)); if (push_items < src_nritems) { - memmove_extent_buffer(src, btrfs_node_key_ptr_offset(0), - btrfs_node_key_ptr_offset(push_items), - (src_nritems - push_items) * - sizeof(struct btrfs_key_ptr)); + __memmove_extent_buffer_log(root->fs_info, src, 0, push_items, + src_nritems - push_items, + sizeof(struct btrfs_key_ptr), 1); } btrfs_set_header_nritems(src, src_nritems - push_items); btrfs_set_header_nritems(dst, dst_nritems + push_items); @@ -2491,15 +2513,13 @@ static int balance_node_right(struct btrfs_trans_handle *trans, if (max_push < push_items) push_items = max_push; - memmove_extent_buffer(dst, btrfs_node_key_ptr_offset(push_items), - btrfs_node_key_ptr_offset(0), - (dst_nritems) * - sizeof(struct btrfs_key_ptr)); + __memmove_extent_buffer_log(root->fs_info, dst, push_items, 0, + dst_nritems, + sizeof(struct btrfs_key_ptr), 1); - copy_extent_buffer(dst, src, - btrfs_node_key_ptr_offset(0), - btrfs_node_key_ptr_offset(src_nritems - push_items), - push_items * sizeof(struct btrfs_key_ptr)); + __copy_extent_buffer_log(root->fs_info, dst, src, 0, + src_nritems - push_items, + push_items, sizeof(struct btrfs_key_ptr)); btrfs_set_header_nritems(src, src_nritems - push_items); btrfs_set_header_nritems(dst, dst_nritems + push_items); @@ -2570,7 +2590,7 @@ static noinline int insert_new_root(struct btrfs_trans_handle *trans, btrfs_mark_buffer_dirty(c); old = root->node; - rcu_assign_pointer(root->node, c); + set_root_pointer(root, c); /* the super has an extra ref to root->node */ free_extent_buffer(old); @@ -2593,10 +2613,11 @@ static noinline int insert_new_root(struct btrfs_trans_handle *trans, static void insert_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, struct btrfs_path *path, struct btrfs_disk_key *key, u64 bytenr, - int slot, int level) + int slot, int level, int tree_mod_log) { struct extent_buffer *lower; int nritems; + int ret; BUG_ON(!path->nodes[level]); btrfs_assert_tree_locked(path->nodes[level]); @@ -2605,10 +2626,15 @@ static void insert_ptr(struct btrfs_trans_handle *trans, BUG_ON(slot > nritems); BUG_ON(nritems == BTRFS_NODEPTRS_PER_BLOCK(root)); if (slot != nritems) { - memmove_extent_buffer(lower, - btrfs_node_key_ptr_offset(slot + 1), - btrfs_node_key_ptr_offset(slot), - (nritems - slot) * sizeof(struct btrfs_key_ptr)); + __memmove_extent_buffer_log(root->fs_info, lower, slot + 1, + slot, nritems - slot, + sizeof(struct btrfs_key_ptr), + tree_mod_log && level); + } + if (tree_mod_log && level) { + ret = tree_mod_log_insert_key(root->fs_info, lower, slot, + MOD_LOG_KEY_ADD); + BUG_ON(ret < 0); } btrfs_set_node_key(lower, key, slot); btrfs_set_node_blockptr(lower, slot, bytenr); @@ -2681,10 +2707,8 @@ static noinline int split_node(struct btrfs_trans_handle *trans, BTRFS_UUID_SIZE); - copy_extent_buffer(split, c, - btrfs_node_key_ptr_offset(0), - btrfs_node_key_ptr_offset(mid), - (c_nritems - mid) * sizeof(struct btrfs_key_ptr)); + __copy_extent_buffer_log(root->fs_info, split, c, 0, mid, + c_nritems - mid, sizeof(struct btrfs_key_ptr)); btrfs_set_header_nritems(split, c_nritems - mid); btrfs_set_header_nritems(c, mid); ret = 0; @@ -2693,7 +2717,7 @@ static noinline int split_node(struct btrfs_trans_handle *trans, btrfs_mark_buffer_dirty(split); insert_ptr(trans, root, path, &disk_key, split->start, - path->slots[level + 1] + 1, level + 1); + path->slots[level + 1] + 1, level + 1, 1); if (path->slots[level] >= mid) { path->slots[level] -= mid; @@ -3230,7 +3254,7 @@ static noinline void copy_for_split(struct btrfs_trans_handle *trans, btrfs_set_header_nritems(l, mid); btrfs_item_key(right, &disk_key, 0); insert_ptr(trans, root, path, &disk_key, right->start, - path->slots[1] + 1, 1); + path->slots[1] + 1, 1, 0); btrfs_mark_buffer_dirty(right); btrfs_mark_buffer_dirty(l); @@ -3437,7 +3461,7 @@ again: if (mid <= slot) { btrfs_set_header_nritems(right, 0); insert_ptr(trans, root, path, &disk_key, right->start, - path->slots[1] + 1, 1); + path->slots[1] + 1, 1, 0); btrfs_tree_unlock(path->nodes[0]); free_extent_buffer(path->nodes[0]); path->nodes[0] = right; @@ -3446,7 +3470,7 @@ again: } else { btrfs_set_header_nritems(right, 0); insert_ptr(trans, root, path, &disk_key, right->start, - path->slots[1], 1); + path->slots[1], 1, 0); btrfs_tree_unlock(path->nodes[0]); free_extent_buffer(path->nodes[0]); path->nodes[0] = right; @@ -4158,19 +4182,27 @@ int btrfs_insert_item(struct btrfs_trans_handle *trans, struct btrfs_root * empty a node. */ static void del_ptr(struct btrfs_trans_handle *trans, struct btrfs_root *root, - struct btrfs_path *path, int level, int slot) + struct btrfs_path *path, int level, int slot, + int tree_mod_log) { struct extent_buffer *parent = path->nodes[level]; u32 nritems; + int ret; nritems = btrfs_header_nritems(parent); if (slot != nritems - 1) { - memmove_extent_buffer(parent, - btrfs_node_key_ptr_offset(slot), - btrfs_node_key_ptr_offset(slot + 1), - sizeof(struct btrfs_key_ptr) * - (nritems - slot - 1)); + __memmove_extent_buffer_log(root->fs_info, parent, slot, + slot + 1, nritems - slot - 1, + sizeof(struct btrfs_key_ptr), + tree_mod_log && level); } + + if (tree_mod_log && level) { + ret = tree_mod_log_insert_key(root->fs_info, parent, slot, + MOD_LOG_KEY_REMOVE); + BUG_ON(ret < 0); + } + nritems--; btrfs_set_header_nritems(parent, nritems); if (nritems == 0 && parent == root->node) { @@ -4202,7 +4234,7 @@ static noinline void btrfs_del_leaf(struct btrfs_trans_handle *trans, struct extent_buffer *leaf) { WARN_ON(btrfs_header_generation(leaf) != trans->transid); - del_ptr(trans, root, path, 1, path->slots[1]); + del_ptr(trans, root, path, 1, path->slots[1], 1); /* * btrfs_free_extent is expensive, we want to make sure we -- 1.7.3.4 -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html