marko10_000
/
btrfs-progs
forked from Mirrors/btrfs-progs
1
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

btrfs-progs: print-tree: Introduce breadth-first search 

Introduce a new function, bfs_print_children(), to do breadth-first
search to print a node.

Reviewed-by: Nikolay Borisov <nborisov@suse.com>
Signed-off-by: Qu Wenruo <wqu@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
master
Qu Wenruo 2018-09-05 14:15:50 +08:00 committed by David Sterba
parent cdd00958e4
commit 61c218756c
1 changed files with 72 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

72
print-tree.c
View File

@ -1381,6 +1381,78 @@ void btrfs_print_leaf(struct extent_buffer *eb)
}
}
/* Helper function to reach the leftmost tree block at @path->lowest_level */
static int search_leftmost_tree_block(struct btrfs_fs_info *fs_info,
struct btrfs_path *path, int root_level)
{
int i;
int ret = 0;
/* Release all nodes except path->nodes[root_level] */
for (i = 0; i < root_level; i++) {
path->slots[i] = 0;
if (!path->nodes[i])
continue;
free_extent_buffer(path->nodes[i]);
}
/* Reach the leftmost tree block by always reading out slot 0 */
for (i = root_level; i > path->lowest_level; i--) {
struct extent_buffer *eb;
path->slots[i] = 0;
eb = read_node_slot(fs_info, path->nodes[i], 0);
if (!extent_buffer_uptodate(eb)) {
ret = -EIO;
goto out;
}
path->nodes[i - 1] = eb;
}
out:
return ret;
}
static void bfs_print_children(struct extent_buffer *root_eb)
{
struct btrfs_fs_info *fs_info = root_eb->fs_info;
struct btrfs_path path;
int root_level = btrfs_header_level(root_eb);
int cur_level;
int ret;
if (root_level < 1)
return;
btrfs_init_path(&path);
/* For path */
extent_buffer_get(root_eb);
path.nodes[root_level] = root_eb;
for (cur_level = root_level - 1; cur_level >= 0; cur_level--) {
path.lowest_level = cur_level;
/* Use the leftmost tree block as a starting point */
ret = search_leftmost_tree_block(fs_info, &path, root_level);
if (ret < 0)
goto out;
/* Print all sibling tree blocks */
while (1) {
btrfs_print_tree(path.nodes[cur_level], 0);
ret = btrfs_next_sibling_tree_block(fs_info, &path);
if (ret < 0)
goto out;
if (ret > 0) {
ret = 0;
break;
}
}
}
out:
btrfs_release_path(&path);
return;
}
void btrfs_print_tree(struct extent_buffer *eb, int follow)
{
u32 i;