From: Anand Jain <anand.j...@oracle.com> Signed-off-by: Anand Jain <anand.j...@oracle.com> --- btrfslabel.c | 45 +++++++++++++++++++++++++++++++++++++++++++++ btrfslabel.h | 4 +++- ctree.h | 4 +++- ioctl.h | 2 ++ print-tree.c | 2 ++ 5 files changed, 55 insertions(+), 2 deletions(-)
diff --git a/btrfslabel.c b/btrfslabel.c index cb142b0..e161af1 100644 --- a/btrfslabel.c +++ b/btrfslabel.c @@ -126,3 +126,48 @@ int set_label(char *btrfs_dev, char *nLabel) change_label_unmounted(btrfs_dev, nLabel); return 0; } + +int get_subvol_label(char *subvol, char *labelp) +{ + int fd, e=0; + + fd = open_file_or_dir(subvol); + + if(ioctl(fd, BTRFS_IOC_SUBVOL_GETLABEL, labelp) < 0) { + e = errno; + fprintf(stderr, "ERROR: get subvol label failed, %s\n", + strerror(e)); + close(fd); + return -e; + } + labelp[BTRFS_LABEL_SIZE] = '\0'; + if (!strlen(labelp)) + return -1; + close(fd); + return 0; +} + +int set_subvol_label(char *subvol, char *labelp) +{ + int fd, e=0; + char label[BTRFS_SUBVOL_LABEL_SIZE+1]; + + if (strlen(labelp) > BTRFS_SUBVOL_LABEL_SIZE) { + fprintf(stderr, "ERROR: Subvol label is more than max length %d\n", + BTRFS_SUBVOL_LABEL_SIZE); + return -1; + } + memset(label, 0, BTRFS_SUBVOL_LABEL_SIZE+1); + strcpy(label, labelp); + fd = open_file_or_dir(subvol); + + if(ioctl(fd, BTRFS_IOC_SUBVOL_SETLABEL, label) < 0) { + e = errno; + fprintf(stderr, "ERROR: set subvol label failed, %s\n", + strerror(e)); + close(fd); + return -e; + } + close(fd); + return 0; +} diff --git a/btrfslabel.h b/btrfslabel.h index abf43ad..1abc483 100644 --- a/btrfslabel.h +++ b/btrfslabel.h @@ -2,4 +2,6 @@ int get_label(char *btrfs_dev); -int set_label(char *btrfs_dev, char *nLabel); \ No newline at end of file +int set_label(char *btrfs_dev, char *nLabel); +int get_subvol_label(char *subvol, char *labelp); +int set_subvol_label(char *subvol, char *labelp); diff --git a/ctree.h b/ctree.h index 293b24f..68bae28 100644 --- a/ctree.h +++ b/ctree.h @@ -325,6 +325,7 @@ struct btrfs_header { */ #define BTRFS_SYSTEM_CHUNK_ARRAY_SIZE 2048 #define BTRFS_LABEL_SIZE 256 +#define BTRFS_SUBVOL_LABEL_SIZE 32 /* * just in case we somehow lose the roots and are not able to mount, @@ -702,7 +703,8 @@ struct btrfs_root_item { struct btrfs_timespec otime; struct btrfs_timespec stime; struct btrfs_timespec rtime; - __le64 reserved[8]; /* for future */ + char label[BTRFS_SUBVOL_LABEL_SIZE]; + __le64 reserved[4]; /* for future */ } __attribute__ ((__packed__)); /* diff --git a/ioctl.h b/ioctl.h index 6fda3a1..009fa6e 100644 --- a/ioctl.h +++ b/ioctl.h @@ -432,4 +432,6 @@ 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_SUBVOL_GETLABEL _IOWR(BTRFS_IOCTL_MAGIC, 55, __u64) +#define BTRFS_IOC_SUBVOL_SETLABEL _IOW(BTRFS_IOCTL_MAGIC, 56, __u64) #endif diff --git a/print-tree.c b/print-tree.c index 7c615dd..5979109 100644 --- a/print-tree.c +++ b/print-tree.c @@ -330,6 +330,8 @@ static void print_root(struct extent_buffer *leaf, int slot) btrfs_root_stransid(&root_item), btrfs_root_rtransid(&root_item)); } + if (strlen(root_item.label)) + printf("\t\tlabel %s\n", root_item.label); } if (btrfs_root_refs(&root_item) == 0) { struct btrfs_key drop_key; -- 1.7.1 -- 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