Re: [PATCH 2/2] bcachefs: Add support for FS_IOC_GETFSSYSFSPATH

[Youling Tang]

On 09/07/2024 10:04, Hongbo Li wrote:
> On 2024/7/9 9:11, Youling Tang wrote:
> > From: Kent Overstreet <kent.overstreet@xxxxxxxxx>
> >
> > [TEST]:
> > ```
> > $ cat ioctl_getsysfspath.c
> >   #include <stdio.h>
> >   #include <stdlib.h>
> >   #include <fcntl.h>
> >   #include <sys/ioctl.h>
> >   #include <linux/fs.h>
> >   #include <unistd.h>
> >
> >   int main(int argc, char *argv[]) {
> >       int fd;
> >       struct fs_sysfs_path sysfs_path = {};
> >
> >       if (argc != 2) {
> >           fprintf(stderr, "Usage: %s <path_to_file_or_directory>\n", 
> > argv[0]);
> >           exit(EXIT_FAILURE);
> >       }
> >
> >       fd = open(argv[1], O_RDONLY);
> >       if (fd == -1) {
> >           perror("open");
> >           exit(EXIT_FAILURE);
> >       }
> >
> >       if (ioctl(fd, FS_IOC_GETFSSYSFSPATH, &sysfs_path) == -1) {
> >           perror("ioctl FS_IOC_GETFSSYSFSPATH");
> >           close(fd);
> >           exit(EXIT_FAILURE);
> >       }
> >
> >       printf("FS_IOC_GETFSSYSFSPATH: %s\n", sysfs_path.name);
> >       close(fd);
> >       return 0;
> >   }
> >
> > $ gcc ioctl_getsysfspath.c
> > $ sudo bcachefs format /dev/sda
> > $ sudo mount.bcachefs /dev/sda /mnt
> > $ sudo ./a.out /mnt
> >    FS_IOC_GETFSSYSFSPATH: bcachefs/c380b4ab-fbb6-41d2-b805-7a89cae9cadb
> > ```
> >
> > Original patch link:
> > [1]: 
> > https://lore.kernel.org/all/20240207025624.1019754-8-kent.overstreet@xxxxxxxxx/
> >
> > Signed-off-by: Kent Overstreet <kent.overstreet@xxxxxxxxx>
> > Signed-off-by: Youling Tang <youling.tang@xxxxxxxxx>
> > ---
> >   fs/bcachefs/fs.c | 1 +
> >   1 file changed, 1 insertion(+)
> >
> > diff --git a/fs/bcachefs/fs.c b/fs/bcachefs/fs.c
> > index 011ee5075a52..8699770398d1 100644
> > --- a/fs/bcachefs/fs.c
> > +++ b/fs/bcachefs/fs.c
> > @@ -1978,6 +1978,7 @@ static int bch2_fs_get_tree(struct fs_context *fc)
> >       sb->s_time_min        = div_s64(S64_MIN, 
> > c->sb.time_units_per_sec) + 1;
> >       sb->s_time_max        = div_s64(S64_MAX, 
> > c->sb.time_units_per_sec);
> >       super_set_uuid(sb, c->sb.user_uuid.b, sizeof(c->sb.user_uuid));
> > +    super_set_sysfs_name_uuid(sb);
>
> Reviewed-by: Hongbo Li <lihongbo22@xxxxxxxxxx>
>
> It's quite strange that other commits have been merged, but the ones 
> for bcachefs have not been merged.
Because bcachefs was not upstream at the time, [1] described the following:
  Note, I dropped the bcachefs changes because they're not upstream yet.
  But once this is a stable branch you can just pull in vfs.uuid and rely
  on that.

[1]: 
https://lore.kernel.org/all/20240208-wecken-nutzen-3df1102a39b2@brauner/

Thanks,
Youling.