| Message ID | 50CF005A.7030206@oracle.com (mailing list archive) |
|---|---|
| State | New, archived |
| Headers | show |
On mon, 17 Dec 2012 19:22:02 +0800, Jeff Liu wrote: > Introduce a new ioctl BTRFS_IOC_GET_FSLABEL to fetch the label of a mounted file system. > > Signed-off-by: Jie Liu <jeff.liu@oracle.com> > Signed-off-by: Anand Jain <anand.jain@oracle.com> > Cc: Miao Xie <miaox@cn.fujitsu.com> Reviewed-by: Miao Xie <miaox@cn.fujitsu.com> > > --- > fs/btrfs/ioctl.c | 15 +++++++++++++++ > fs/btrfs/ioctl.h | 2 ++ > 2 files changed, 17 insertions(+) > > diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c > index 8fcf9a5..6a2488a 100644 > --- a/fs/btrfs/ioctl.c > +++ b/fs/btrfs/ioctl.c > @@ -3699,6 +3699,19 @@ out: > return ret; > } > > +static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg) > +{ > + struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; > + const char *label = root->fs_info->super_copy->label; > + int ret; > + > + mutex_lock(&root->fs_info->volume_mutex); > + ret = copy_to_user(arg, label, strlen(label)); > + mutex_unlock(&root->fs_info->volume_mutex); > + > + return ret ? -EFAULT : 0; > +} > + > long btrfs_ioctl(struct file *file, unsigned int > cmd, unsigned long arg) > { > @@ -3797,6 +3810,8 @@ 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_FSLABEL: > + return btrfs_ioctl_get_fslabel(file, argp); > } > > return -ENOTTY; > diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h > index 731e287..5b2cbef 100644 > --- a/fs/btrfs/ioctl.h > +++ b/fs/btrfs/ioctl.h > @@ -451,6 +451,8 @@ struct btrfs_ioctl_send_args { > struct btrfs_ioctl_qgroup_create_args) > #define BTRFS_IOC_QGROUP_LIMIT _IOR(BTRFS_IOCTL_MAGIC, 43, \ > struct btrfs_ioctl_qgroup_limit_args) > +#define BTRFS_IOC_GET_FSLABEL _IOR(BTRFS_IOCTL_MAGIC, 49, \ > + char[BTRFS_LABEL_SIZE]) > #define BTRFS_IOC_GET_DEV_STATS _IOWR(BTRFS_IOCTL_MAGIC, 52, \ > struct btrfs_ioctl_get_dev_stats) > #endif > -- To unsubscribe from this list: send the line "unsubscribe linux-btrfs" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index 8fcf9a5..6a2488a 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -3699,6 +3699,19 @@ out: return ret; } +static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg) +{ + struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; + const char *label = root->fs_info->super_copy->label; + int ret; + + mutex_lock(&root->fs_info->volume_mutex); + ret = copy_to_user(arg, label, strlen(label)); + mutex_unlock(&root->fs_info->volume_mutex); + + return ret ? -EFAULT : 0; +} + long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -3797,6 +3810,8 @@ 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_FSLABEL: + return btrfs_ioctl_get_fslabel(file, argp); } return -ENOTTY; diff --git a/fs/btrfs/ioctl.h b/fs/btrfs/ioctl.h index 731e287..5b2cbef 100644 --- a/fs/btrfs/ioctl.h +++ b/fs/btrfs/ioctl.h @@ -451,6 +451,8 @@ struct btrfs_ioctl_send_args { struct btrfs_ioctl_qgroup_create_args) #define BTRFS_IOC_QGROUP_LIMIT _IOR(BTRFS_IOCTL_MAGIC, 43, \ struct btrfs_ioctl_qgroup_limit_args) +#define BTRFS_IOC_GET_FSLABEL _IOR(BTRFS_IOCTL_MAGIC, 49, \ + char[BTRFS_LABEL_SIZE]) #define BTRFS_IOC_GET_DEV_STATS _IOWR(BTRFS_IOCTL_MAGIC, 52, \ struct btrfs_ioctl_get_dev_stats) #endif