diff options
| -rw-r--r-- | btrfslabel.c | 82 | ||||
| -rw-r--r-- | ioctl.h | 4 |
2 files changed, 55 insertions, 31 deletions
diff --git a/btrfslabel.c b/btrfslabel.c index a421a8b3..7aea996e 100644 --- a/btrfslabel.c +++ b/btrfslabel.c @@ -46,26 +46,58 @@ #define GET_LABEL 3 #define SET_LABEL 4 -static int change_label_unmounted(char *dev, char *nLabel) +static int set_label_unmounted(const char *dev, const char *label) { - struct btrfs_root *root; - struct btrfs_trans_handle *trans; + struct btrfs_trans_handle *trans; + struct btrfs_root *root; + int ret; - /* Open the super_block at the default location - * and as read-write. - */ - root = open_ctree(dev, 0, 1); - if (!root) /* errors are printed by open_ctree() */ + ret = check_mounted(dev); + if (ret < 0) { + fprintf(stderr, "FATAL: error checking %s mount status\n", dev); return -1; + } + if (ret > 0) { + fprintf(stderr, "ERROR: dev %s is mounted, use mount point\n", + dev); + return -1; + } - trans = btrfs_start_transaction(root, 1); - strncpy(root->fs_info->super_copy.label, nLabel, BTRFS_LABEL_SIZE); - root->fs_info->super_copy.label[BTRFS_LABEL_SIZE-1] = 0; - btrfs_commit_transaction(trans, root); + /* Open the super_block at the default location + * and as read-write. + */ + root = open_ctree(dev, 0, 1); + if (!root) /* errors are printed by open_ctree() */ + return -1; + + trans = btrfs_start_transaction(root, 1); + strncpy(root->fs_info->super_copy.label, label, BTRFS_LABEL_SIZE); + root->fs_info->super_copy.label[BTRFS_LABEL_SIZE-1] = 0; + btrfs_commit_transaction(trans, root); + + /* Now we close it since we are done. */ + close_ctree(root); + return 0; +} - /* Now we close it since we are done. */ - close_ctree(root); - return 0; +static int set_label_mounted(const char *mount_path, const char *label) +{ + int fd; + + fd = open(mount_path, O_RDONLY | O_NOATIME); + if (fd < 0) { + fprintf(stderr, "ERROR: unable access to '%s'\n", mount_path); + return -1; + } + + if (ioctl(fd, BTRFS_IOC_SET_FSLABEL, label) < 0) { + fprintf(stderr, "ERROR: unable to set label %s\n", + strerror(errno)); + close(fd); + return -1; + } + + return 0; } int get_label_unmounted(char *dev) @@ -108,21 +140,9 @@ int get_label(char *btrfs_dev) } -int set_label(char *btrfs_dev, char *nLabel) +int set_label(char *btrfs_dev, char *label) { - - int ret; - ret = check_mounted(btrfs_dev); - if (ret < 0) - { - fprintf(stderr, "FATAL: error checking %s mount status\n", btrfs_dev); - return -1; - } - - if(ret != 0) - { - fprintf(stderr, "FATAL: the filesystem has to be unmounted\n"); - return -2; - } - return change_label_unmounted(btrfs_dev, nLabel); + return is_existing_blk_or_reg_file(btrfs_dev) ? + set_label_unmounted(btrfs_dev, label) : + set_label_mounted(btrfs_dev, label); } @@ -520,6 +520,10 @@ struct btrfs_ioctl_clone_range_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_SET_FSLABEL _IOW(BTRFS_IOCTL_MAGIC, 50, \ + char[BTRFS_LABEL_SIZE]) #define BTRFS_IOC_GET_DEV_STATS _IOWR(BTRFS_IOCTL_MAGIC, 52, \ struct btrfs_ioctl_get_dev_stats) #define BTRFS_IOC_DEV_REPLACE _IOWR(BTRFS_IOCTL_MAGIC, 53, \ |