nilfs2: add support for FS_IOC_GETUUID

Patch series "nilfs2: add support for some common ioctls".

This series adds support for common ioctls to nilfs2 for getting the
volume UUID and the relative path of an FS instance within the sysfs
namespace, and also implements ioctls for nilfs2 to get and set the volume
label.

This patch (of 2):

Expose the UUID of a file system instance using the super_set_uuid helper
and support the FS_IOC_GETUUID ioctl.

Link: https://lkml.kernel.org/r/20240815074408.5550-1-konishi.ryusuke@gmail.com
Link: https://lkml.kernel.org/r/20240815074408.5550-2-konishi.ryusuke@gmail.com
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@gmail.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>

diff --git a/fs/nilfs2/super.c b/fs/nilfs2/super.c
index e835e1f5a71201ab823c7cb5372ccf490c98641b..167050b3ce7e0865e23dbb475a8732927966cbea 100644 (file)
--- a/fs/nilfs2/super.c
+++ b/fs/nilfs2/super.c
@@ -1063,6 +1063,9 @@ nilfs_fill_super(struct super_block *sb, struct fs_context *fc)
        if (err)
                goto failed_nilfs;
 
+       super_set_uuid(sb, nilfs->ns_sbp[0]->s_uuid,
+                      sizeof(nilfs->ns_sbp[0]->s_uuid));
+
        cno = nilfs_last_cno(nilfs);
        err = nilfs_attach_checkpoint(sb, cno, true, &fsroot);
        if (err) {