static noinline int
tree_mod_log_insert_root(struct btrfs_fs_info *fs_info,
struct extent_buffer *old_root,
- struct extent_buffer *new_root, gfp_t flags)
+ struct extent_buffer *new_root, gfp_t flags,
+ int log_removal)
{
struct tree_mod_elem *tm;
int ret;
if (tree_mod_dont_log(fs_info, NULL))
return 0;
- __tree_mod_log_free_eb(fs_info, old_root);
+ if (log_removal)
+ __tree_mod_log_free_eb(fs_info, old_root);
ret = tree_mod_alloc(fs_info, flags, &tm);
if (ret < 0)
static noinline void
tree_mod_log_eb_copy(struct btrfs_fs_info *fs_info, struct extent_buffer *dst,
struct extent_buffer *src, unsigned long dst_offset,
- unsigned long src_offset, int nr_items, int log_removal)
+ unsigned long src_offset, int nr_items)
{
int ret;
int i;
}
for (i = 0; i < nr_items; i++) {
- if (log_removal) {
- ret = tree_mod_log_insert_key_locked(fs_info, src,
- i + src_offset,
- MOD_LOG_KEY_REMOVE);
- BUG_ON(ret < 0);
- }
+ ret = tree_mod_log_insert_key_locked(fs_info, src,
+ i + src_offset,
+ MOD_LOG_KEY_REMOVE);
+ BUG_ON(ret < 0);
ret = tree_mod_log_insert_key_locked(fs_info, dst,
i + dst_offset,
MOD_LOG_KEY_ADD);
static noinline void
tree_mod_log_set_root_pointer(struct btrfs_root *root,
- struct extent_buffer *new_root_node)
+ struct extent_buffer *new_root_node,
+ int log_removal)
{
int ret;
ret = tree_mod_log_insert_root(root->fs_info, root->node,
- new_root_node, GFP_NOFS);
+ new_root_node, GFP_NOFS, log_removal);
BUG_ON(ret < 0);
}
parent_start = 0;
extent_buffer_get(cow);
- tree_mod_log_set_root_pointer(root, cow);
+ tree_mod_log_set_root_pointer(root, cow, 1);
rcu_assign_pointer(root->node, cow);
btrfs_free_tree_block(trans, root, buf, parent_start,
goto enospc;
}
- tree_mod_log_set_root_pointer(root, child);
+ tree_mod_log_set_root_pointer(root, child, 1);
rcu_assign_pointer(root->node, child);
add_root_to_dirty_list(root);
push_items = min(src_nritems - 8, push_items);
tree_mod_log_eb_copy(root->fs_info, dst, src, dst_nritems, 0,
- push_items, 1);
+ push_items);
copy_extent_buffer(dst, src,
btrfs_node_key_ptr_offset(dst_nritems),
btrfs_node_key_ptr_offset(0),
sizeof(struct btrfs_key_ptr));
tree_mod_log_eb_copy(root->fs_info, dst, src, 0,
- src_nritems - push_items, push_items, 1);
+ 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),
*/
static noinline int insert_new_root(struct btrfs_trans_handle *trans,
struct btrfs_root *root,
- struct btrfs_path *path, int level)
+ struct btrfs_path *path, int level, int log_removal)
{
u64 lower_gen;
struct extent_buffer *lower;
btrfs_mark_buffer_dirty(c);
old = root->node;
- tree_mod_log_set_root_pointer(root, c);
+ tree_mod_log_set_root_pointer(root, c, log_removal);
rcu_assign_pointer(root->node, c);
/* the super has an extra ref to root->node */
int mid;
int ret;
u32 c_nritems;
- int tree_mod_log_removal = 1;
c = path->nodes[level];
WARN_ON(btrfs_header_generation(c) != trans->transid);
if (c == root->node) {
- /* trying to split the root, lets make a new one */
- ret = insert_new_root(trans, root, path, level + 1);
/*
- * removal of root nodes has been logged by
- * tree_mod_log_set_root_pointer due to locking
+ * trying to split the root, lets make a new one
+ *
+ * tree mod log: We pass 0 as log_removal parameter to
+ * insert_new_root, because that root buffer will be kept as a
+ * normal node. We are going to log removal of half of the
+ * elements below with tree_mod_log_eb_copy. We're holding a
+ * tree lock on the buffer, which is why we cannot race with
+ * other tree_mod_log users.
*/
- tree_mod_log_removal = 0;
+ ret = insert_new_root(trans, root, path, level + 1, 0);
if (ret)
return ret;
} else {
(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,
- tree_mod_log_removal);
+ 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),
}
if (!path->nodes[1]) {
- ret = insert_new_root(trans, root, path, 1);
+ ret = insert_new_root(trans, root, path, 1, 1);
if (ret)
return ret;
}