From: Al Viro <viro@zeniv.linux.org.uk>
Date: Thu, 9 May 2024 05:07:01 +0000 (-0400)
Subject: convert fuse_ctl
X-Git-Tag: v6.19-rc1~111^2~37
X-Git-Url: http://git.ipfire.org/cgi-bin/gitweb.cgi?a=commitdiff_plain;h=5a8993a15a79f03cd1a43ddc071d0e49a1247cd5;p=thirdparty%2Fkernel%2Flinux.git

convert fuse_ctl

objects are created in fuse_ctl_add_dentry() by d_alloc_name()+d_add(),
removed by simple_remove_by_name().

What we return is a borrowed reference - it is valid until the call of
fuse_ctl_remove_conn() and we depend upon the exclusion (on fuse_mutex)
for safety.  Return value is used only within the caller
(fuse_ctl_add_conn()).

Replace d_add() with d_make_persistent() + dput().  dput() is paired
with d_alloc_name() and return value is the result of d_make_persistent().

Acked-by: Miklos Szeredi <mszeredi@redhat.com>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
---

diff --git a/fs/fuse/control.c b/fs/fuse/control.c
index 3dca752127ff8..140bd5730d998 100644
--- a/fs/fuse/control.c
+++ b/fs/fuse/control.c
@@ -236,8 +236,14 @@ static struct dentry *fuse_ctl_add_dentry(struct dentry *parent,
 		inc_nlink(inode);
 	}
 	inode->i_private = fc;
-	d_add(dentry, inode);
-
+	d_make_persistent(dentry, inode);
+	dput(dentry);
+
+	/*
+	 * We are returning a borrowed reference here - it's only good while
+	 * fuse_mutex is held.  Actually it's d_make_persistent() return
+	 * value...
+	 */
 	return dentry;
 }
 
@@ -346,7 +352,7 @@ static void fuse_ctl_kill_sb(struct super_block *sb)
 	fuse_control_sb = NULL;
 	mutex_unlock(&fuse_mutex);
 
-	kill_litter_super(sb);
+	kill_anon_super(sb);
 }
 
 static struct file_system_type fuse_ctl_fs_type = {