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
