diff options
Diffstat (limited to 'fs')
| -rw-r--r-- | fs/btrfs/ioctl.c | 42 |
1 files changed, 42 insertions, 0 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index fcc15a6804a9..0f68729f261e 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -3936,6 +3936,46 @@ static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg) return ret ? -EFAULT : 0; } +static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg) +{ + struct btrfs_root *root = BTRFS_I(fdentry(file)->d_inode)->root; + struct btrfs_super_block *super_block = root->fs_info->super_copy; + struct btrfs_trans_handle *trans; + char label[BTRFS_LABEL_SIZE]; + int ret; + + if (!capable(CAP_SYS_ADMIN)) + return -EPERM; + + if (copy_from_user(label, arg, sizeof(label))) + return -EFAULT; + + if (strnlen(label, BTRFS_LABEL_SIZE) == BTRFS_LABEL_SIZE) { + pr_err("btrfs: unable to set label with more than %d bytes\n", + BTRFS_LABEL_SIZE - 1); + return -EINVAL; + } + + ret = mnt_want_write_file(file); + if (ret) + return ret; + + mutex_lock(&root->fs_info->volume_mutex); + trans = btrfs_start_transaction(root, 0); + if (IS_ERR(trans)) { + ret = PTR_ERR(trans); + goto out_unlock; + } + + strcpy(super_block->label, label); + ret = btrfs_end_transaction(trans, root); + +out_unlock: + mutex_unlock(&root->fs_info->volume_mutex); + mnt_drop_write_file(file); + return ret; +} + long btrfs_ioctl(struct file *file, unsigned int cmd, unsigned long arg) { @@ -4038,6 +4078,8 @@ long btrfs_ioctl(struct file *file, unsigned int return btrfs_ioctl_dev_replace(root, argp); case BTRFS_IOC_GET_FSLABEL: return btrfs_ioctl_get_fslabel(file, argp); + case BTRFS_IOC_SET_FSLABEL: + return btrfs_ioctl_set_fslabel(file, argp); } return -ENOTTY; |