[PATCH RFC 5/8] dcache: add action D_WALK_SKIP_SIBLINGS to d_walk()

Konstantin Khlebnikov
2020-05-08T12:23:31Z

This lets skip remaining siblings at seeing d_is_tail_negative().

Signed-off-by: Konstantin Khlebnikov <khlebnikov@yandex-team.ru>
---
fs/dcache.c | 7 +++++++
1 file changed, 7 insertions(+)

diff --git a/fs/dcache.c b/fs/dcache.c
index 743255773cc7..44c6832d21d6 100644
--- a/fs/dcache.c
+++ b/fs/dcache.c
@@ -1303,12 +1303,14 @@ EXPORT_SYMBOL(shrink_dcache_sb);
* @D_WALK_QUIT: quit walk
* @D_WALK_NORETRY: quit when retry is needed
* @D_WALK_SKIP: skip this dentry and its children
+ * @D_WALK_SKIP_SIBLINGS: skip siblings and their children
*/
enum d_walk_ret {
D_WALK_CONTINUE,
D_WALK_QUIT,
D_WALK_NORETRY,
D_WALK_SKIP,
+ D_WALK_SKIP_SIBLINGS,
};

/**
@@ -1339,6 +1341,7 @@ static void d_walk(struct dentry *parent, void *data,
break;
case D_WALK_QUIT:
case D_WALK_SKIP:
+ case D_WALK_SKIP_SIBLINGS:
goto out_unlock;
case D_WALK_NORETRY:
retry = false;
@@ -1370,6 +1373,9 @@ static void d_walk(struct dentry *parent, void *data,
case D_WALK_SKIP:
spin_unlock(&dentry->d_lock);
continue;
+ case D_WALK_SKIP_SIBLINGS:
+ spin_unlock(&dentry->d_lock);
+ goto skip_siblings;
}

if (!list_empty(&dentry->d_subdirs)) {
@@ -1381,6 +1387,7 @@ static void d_walk(struct dentry *parent, void *data,
}
spin_unlock(&dentry->d_lock);
}
+skip_siblings:
/*
* All done at this level ... ascend and resume the search.
*/