GitHub-Mirror/linux-bl808
2
0
Fork 0
mirror of https://github.com/Fishwaldo/linux-bl808.git synced 2025-06-17 20:25:19 +00:00
Code Issues Projects Releases Packages Wiki Activity Actions

btrfs: backref: rename and move remove_backref_node()

Browse source 
Also add comment explaining the cleanup progress, to differ it from
btrfs_backref_drop_node().

Signed-off-by: Qu Wenruo <wqu@suse.com>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
This commit is contained in:
Qu Wenruo 2020-03-23 15:42:25 +08:00 • committed by David Sterba
parent b0fe7078d6
commit 023acb07bc
3 changed files with 53 additions and 48 deletions
Download patch file Download diff file Expand all files Collapse all files

45
fs/btrfs/backref.c
View file

@ -2514,3 +2514,48 @@ struct btrfs_backref_edge *btrfs_backref_alloc_edge(
cache->nr_edges++;
return edge;
}
/*
* Drop the backref node from cache, also cleaning up all its
* upper edges and any uncached nodes in the path.
*
* This cleanup happens bottom up, thus the node should either
* be the lowest node in the cache or a detached node.
*/
void btrfs_backref_cleanup_node(struct btrfs_backref_cache *cache,
struct btrfs_backref_node *node)
{
struct btrfs_backref_node *upper;
struct btrfs_backref_edge *edge;
if (!node)
return;
BUG_ON(!node->lowest && !node->detached);
while (!list_empty(&node->upper)) {
edge = list_entry(node->upper.next, struct btrfs_backref_edge,
list[LOWER]);
upper = edge->node[UPPER];
list_del(&edge->list[LOWER]);
list_del(&edge->list[UPPER]);
btrfs_backref_free_edge(cache, edge);
if (RB_EMPTY_NODE(&upper->rb_node)) {
BUG_ON(!list_empty(&node->upper));
btrfs_backref_drop_node(cache, node);
node = upper;
node->lowest = 1;
continue;
}
/*
* Add the node to leaf node list if no other child block
* cached.
*/
if (list_empty(&upper->lower)) {
list_add_tail(&upper->lower, &cache->leaves);
upper->lowest = 1;
}
}
btrfs_backref_drop_node(cache, node);
}