From a4af51ce229b1e1eab003966dbfebf9d80093a77 Mon Sep 17 00:00:00 2001
From: Kent Overstreet <kent.overstreet@linux.dev>
Date: Tue, 6 Feb 2024 21:56:15 -0500
Subject: fs: super_set_uuid()
Some weird old filesytems have UUID-like things that we wish to expose
as UUIDs, but are smaller; add a length field so that the new
FS_IOC_(GET|SET)UUID ioctls can handle them in generic code.
And add a helper super_set_uuid(), for setting nonstandard length uuids.
Helper is now required for the new FS_IOC_GETUUID ioctl; if
super_set_uuid() hasn't been called, the ioctl won't be supported.
Reviewed-by: Dave Chinner <dchinner@redhat.com>
Signed-off-by: Kent Overstreet <kent.overstreet@linux.dev>
Link: https://lore.kernel.org/r/20240207025624.1019754-2-kent.overstreet@linux.dev
Signed-off-by: Christian Brauner <brauner@kernel.org>
---
mm/shmem.c | 4 +++-
1 file changed, 3 insertions(+), 1 deletion(-)
(limited to 'mm')
diff --git a/mm/shmem.c b/mm/shmem.c
index d7c84ff62186..be41955e52da 100644
--- a/mm/shmem.c
+++ b/mm/shmem.c
@@ -4355,7 +4355,9 @@ static int shmem_fill_super(struct super_block *sb, struct fs_context *fc)
#ifdef CONFIG_TMPFS_POSIX_ACL
sb->s_flags |= SB_POSIXACL;
#endif
- uuid_gen(&sb->s_uuid);
+ uuid_t uuid;
+ uuid_gen(&uuid);
+ super_set_uuid(sb, uuid.b, sizeof(uuid));
#ifdef CONFIG_TMPFS_QUOTA
if (ctx->seen & SHMEM_SEEN_QUOTA) {
--
cgit