diff options
Diffstat (limited to 'fs/btrfs/ioctl.c')
| -rw-r--r-- | fs/btrfs/ioctl.c | 16 |
1 files changed, 10 insertions, 6 deletions
diff --git a/fs/btrfs/ioctl.c b/fs/btrfs/ioctl.c index f856c97952d..556b3d5b18d 100644 --- a/fs/btrfs/ioctl.c +++ b/fs/btrfs/ioctl.c @@ -4042,18 +4042,22 @@ out: static int btrfs_ioctl_get_fslabel(struct file *file, void __user *arg) { struct btrfs_root *root = BTRFS_I(file_inode(file))->root; - const char *label = root->fs_info->super_copy->label; - size_t len = strnlen(label, BTRFS_LABEL_SIZE); + size_t len; int ret; + char label[BTRFS_LABEL_SIZE]; + + spin_lock(&root->fs_info->super_lock); + memcpy(label, root->fs_info->super_copy->label, BTRFS_LABEL_SIZE); + spin_unlock(&root->fs_info->super_lock); + + len = strnlen(label, BTRFS_LABEL_SIZE); if (len == BTRFS_LABEL_SIZE) { pr_warn("btrfs: label is too long, return the first %zu bytes\n", --len); } - mutex_lock(&root->fs_info->volume_mutex); ret = copy_to_user(arg, label, len); - mutex_unlock(&root->fs_info->volume_mutex); return ret ? -EFAULT : 0; } @@ -4082,18 +4086,18 @@ static int btrfs_ioctl_set_fslabel(struct file *file, void __user *arg) 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; } + spin_lock(&root->fs_info->super_lock); strcpy(super_block->label, label); + spin_unlock(&root->fs_info->super_lock); ret = btrfs_end_transaction(trans, root); out_unlock: - mutex_unlock(&root->fs_info->volume_mutex); mnt_drop_write_file(file); return ret; } |