Hi Anand, I have posted a patch for set label back to last year, which can be found at: https://patchwork.kernel.org/patch/1124642/
Besides that, we have discussed to use 50 as the ioctl(2) number at that time. task assignment in our wiki page: https://btrfs.wiki.kernel.org/index.php/Project_ideas#Set.2Fchange_file_system_label Thanks, -Jeff On 08/29/12 16:46, Anand jain wrote: > From: Anand Jain <anand.j...@oracle.com> > > Signed-off-by: Anand Jain <anand.j...@oracle.com> > --- > fs/btrfs/ctree.h | 10 ++++++++++ > fs/btrfs/ioctl.c | 30 ++++++++++++++++++++++++++++++ > fs/btrfs/ioctl.h | 2 ++ > 3 files changed, 42 insertions(+), 0 deletions(-) > > diff --git a/fs/btrfs/ctree.h b/fs/btrfs/ctree.h > index 4bab807..eff506f 100644 > --- a/fs/btrfs/ctree.h > +++ b/fs/btrfs/ctree.h > @@ -2583,6 +2583,16 @@ BTRFS_SETGET_STACK_FUNCS(super_csum_type, struct > btrfs_super_block, > BTRFS_SETGET_STACK_FUNCS(super_cache_generation, struct btrfs_super_block, > cache_generation, 64); > > +static inline char * btrfs_super_label(struct btrfs_super_block *s) > +{ > + return s->label; > +} > +static inline void btrfs_set_super_label(struct btrfs_super_block *s, > + char *val) > +{ > + memcpy(s->label,val,BTRFS_LABEL_SIZE); > +} > + > static inline int btrfs_super_csum_size(struct btrfs_super_block *s) > { > int t = btrfs_super_csum_type(s); > diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c > index 7bb7556..b472942 100644 > --- a/fs/btrfs/ioctl.c > +++ b/fs/btrfs/ioctl.c > @@ -3687,6 +3687,32 @@ out: > return ret; > } > > +static int btrfs_ioctl_get_label(struct btrfs_root *root, void __user *arg) > +{ > + char *label; > + label = btrfs_super_label(root->fs_info->super_copy); > + if (copy_to_user(arg, label, BTRFS_LABEL_SIZE)) > + return -EFAULT; > + return 0; > +} > + > +static int btrfs_ioctl_set_label(struct btrfs_root *root, void __user *arg) > +{ > + struct btrfs_trans_handle *trans; > + char label[BTRFS_LABEL_SIZE+1]; > + > + if (!capable(CAP_SYS_ADMIN)) > + return -EPERM; > + if (copy_from_user(label, arg, BTRFS_LABEL_SIZE)) > + return -EFAULT; > + label[BTRFS_LABEL_SIZE] = '\0'; > + trans = btrfs_start_transaction(root, 1); > + btrfs_set_super_label(root->fs_info->super_copy, label); > + btrfs_commit_transaction(trans, root); > + > + return 0; > +} > + > long btrfs_ioctl(struct file *file, unsigned int > cmd, unsigned long arg) > { > @@ -3785,6 +3811,10 @@ long btrfs_ioctl(struct file *file, unsigned int > return btrfs_ioctl_qgroup_create(root, argp); > case BTRFS_IOC_QGROUP_LIMIT: > return btrfs_ioctl_qgroup_limit(root, argp); > + case BTRFS_IOC_GET_LABEL: > + return btrfs_ioctl_get_label(root, argp); > + case BTRFS_IOC_SET_LABEL: > + return btrfs_ioctl_set_label(root, argp); > } > > return -ENOTTY; > diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h > index 731e287..0c60fcb 100644 > --- a/fs/btrfs/ioctl.h > +++ b/fs/btrfs/ioctl.h > @@ -453,4 +453,6 @@ struct btrfs_ioctl_send_args { > struct btrfs_ioctl_qgroup_limit_args) > #define BTRFS_IOC_GET_DEV_STATS _IOWR(BTRFS_IOCTL_MAGIC, 52, \ > struct btrfs_ioctl_get_dev_stats) > +#define BTRFS_IOC_GET_LABEL _IOR(BTRFS_IOCTL_MAGIC, 53, __u64) > +#define BTRFS_IOC_SET_LABEL _IOW(BTRFS_IOCTL_MAGIC, 54, __u64) > #endif -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majord...@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
