fs: change d_delete semantics
Change d_delete from a dentry deletion notification to a dentry caching
advise, more like ->drop_inode. Require it to be constant and idempotent,
and not take d_lock. This is how all existing filesystems use the callback
anyway.
This makes fine grained dentry locking of dput and dentry lru scanning
much simpler.
Signed-off-by: Nick Piggin <npiggin@kernel.dk>
diff --git a/fs/libfs.c b/fs/libfs.c
index a3accdf..b9d25d8 100644
--- a/fs/libfs.c
+++ b/fs/libfs.c
@@ -37,7 +37,7 @@
* Retaining negative dentries for an in-memory filesystem just wastes
* memory and lookup time: arrange for them to be deleted immediately.
*/
-static int simple_delete_dentry(struct dentry *dentry)
+static int simple_delete_dentry(const struct dentry *dentry)
{
return 1;
}