diff options
Diffstat (limited to 'fs/btrfs/super.c')
| -rw-r--r-- | fs/btrfs/super.c | 28 |
1 files changed, 7 insertions, 21 deletions
diff --git a/fs/btrfs/super.c b/fs/btrfs/super.c index 926d7a9ed99d..881d62d81b9f 100644 --- a/fs/btrfs/super.c +++ b/fs/btrfs/super.c @@ -1979,25 +1979,10 @@ error: * fsconfig(FSCONFIG_SET_FLAG, "ro"). This option is seen by the filesystem * in fc->sb_flags. * - * This disambiguation has rather positive consequences. Mounting a subvolume - * ro will not also turn the superblock ro. Only the mount for the subvolume - * will become ro. - * - * So, if the superblock creation request comes from the new mount API the - * caller must have explicitly done: - * - * fsconfig(FSCONFIG_SET_FLAG, "ro") - * fsmount/mount_setattr(MOUNT_ATTR_RDONLY) - * - * IOW, at some point the caller must have explicitly turned the whole - * superblock ro and we shouldn't just undo it like we did for the old mount - * API. In any case, it lets us avoid the hack in the new mount API. - * - * Consequently, the remounting hack must only be used for requests originating - * from the old mount API and should be marked for full deprecation so it can be - * turned off in a couple of years. - * - * The new mount API has no reason to support this hack. + * But, currently the util-linux mount command already utilizes the new mount + * API and is still setting fsconfig(FSCONFIG_SET_FLAG, "ro") no matter if it's + * btrfs or not, setting the whole super block RO. To make per-subvolume mounting + * work with different options work we need to keep backward compatibility. */ static struct vfsmount *btrfs_reconfigure_for_mount(struct fs_context *fc) { @@ -2019,7 +2004,7 @@ static struct vfsmount *btrfs_reconfigure_for_mount(struct fs_context *fc) if (IS_ERR(mnt)) return mnt; - if (!fc->oldapi || !ro2rw) + if (!ro2rw) return mnt; /* We need to convert to rw, call reconfigure. */ @@ -2206,7 +2191,8 @@ static struct file_system_type btrfs_fs_type = { .init_fs_context = btrfs_init_fs_context, .parameters = btrfs_fs_parameters, .kill_sb = btrfs_kill_super, - .fs_flags = FS_REQUIRES_DEV | FS_BINARY_MOUNTDATA | FS_ALLOW_IDMAP, + .fs_flags = FS_REQUIRES_DEV | FS_BINARY_MOUNTDATA | + FS_ALLOW_IDMAP | FS_MGTIME, }; MODULE_ALIAS_FS("btrfs"); |