From 7bb1eb45e43c4730cbc5a48b9e9295049fccdacb Mon Sep 17 00:00:00 2001 From: NeilBrown Date: Thu, 13 Nov 2025 11:18:31 +1100 Subject: VFS: introduce start_removing_dentry() start_removing_dentry() is similar to start_removing() but instead of providing a name for lookup, the target dentry is given. start_removing_dentry() checks that the dentry is still hashed and in the parent, and if so it locks and increases the refcount so that end_removing() can be used to finish the operation. This is used in cachefiles, overlayfs, smb/server, and apparmor. There will be other users including ecryptfs. As start_removing_dentry() takes an extra reference to the dentry (to be put by end_removing()), there is no need to explicitly take an extra reference to stop d_delete() from using dentry_unlink_inode() to negate the dentry - as in cachefiles_delete_object(), and ksmbd_vfs_unlink(). cachefiles_bury_object() now gets an extra ref to the victim, which is drops. As it includes the needed end_removing() calls, the caller doesn't need them. Reviewed-by: Amir Goldstein Reviewed-by: Namjae Jeon Reviewed-by: Jeff Layton Signed-off-by: NeilBrown Link: https://patch.msgid.link/20251113002050.676694-9-neilb@ownmail.net Signed-off-by: Christian Brauner --- fs/cachefiles/interface.c | 11 +++++++---- 1 file changed, 7 insertions(+), 4 deletions(-) (limited to 'fs/cachefiles/interface.c') diff --git a/fs/cachefiles/interface.c b/fs/cachefiles/interface.c index 3e63cfe15874..a08250d244ea 100644 --- a/fs/cachefiles/interface.c +++ b/fs/cachefiles/interface.c @@ -9,6 +9,7 @@ #include #include #include +#include #include #include #include "internal.h" @@ -428,11 +429,13 @@ static bool cachefiles_invalidate_cookie(struct fscache_cookie *cookie) if (!old_tmpfile) { struct cachefiles_volume *volume = object->volume; struct dentry *fan = volume->fanout[(u8)cookie->key_hash]; + struct dentry *obj; - inode_lock_nested(d_inode(fan), I_MUTEX_PARENT); - cachefiles_bury_object(volume->cache, object, fan, - old_file->f_path.dentry, - FSCACHE_OBJECT_INVALIDATED); + obj = start_removing_dentry(fan, old_file->f_path.dentry); + if (!IS_ERR(obj)) + cachefiles_bury_object(volume->cache, object, + fan, obj, + FSCACHE_OBJECT_INVALIDATED); } fput(old_file); } -- cgit v1.2.3