Implement support for FS_IOC_SETFSLABEL ioctl to write filesystem
label.
Signed-off-by: Ryusuke Konishi <konishi.ryusuke@xxxxxxxxx>
---
fs/nilfs2/ioctl.c | 65 +++++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 65 insertions(+)
diff --git a/fs/nilfs2/ioctl.c b/fs/nilfs2/ioctl.c
index b5c6a50d6d5d..297989e51ee6 100644
--- a/fs/nilfs2/ioctl.c
+++ b/fs/nilfs2/ioctl.c
@@ -1290,6 +1290,68 @@ static int nilfs_ioctl_get_fslabel(struct super_block *sb, void __user *argp)
return 0;
}
+/**
+ * nilfs_ioctl_set_fslabel - set the volume name of the file system
+ * @sb: super block instance
+ * @filp: file object
+ * @argp: pointer to userspace memory that contains the volume name
+ *
+ * Return: 0 on success, or the following negative error code on failure.
+ * * %-EFAULT - Error copying input data.
+ * * %-EINVAL - Label length exceeds record size in superblock.
+ * * %-EIO - I/O error.
+ * * %-EPERM - Operation not permitted (insufficient permissions).
+ * * %-EROFS - Read only file system.
+ */
+static int nilfs_ioctl_set_fslabel(struct super_block *sb, struct file *filp,
+ void __user *argp)
+{
+ char label[NILFS_MAX_VOLUME_NAME + 1];
+ struct the_nilfs *nilfs = sb->s_fs_info;
+ struct nilfs_super_block **sbp;
+ size_t len;
+ int ret;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+
+ ret = mnt_want_write_file(filp);
+ if (ret)
+ return ret;
+
+ if (copy_from_user(label, argp, NILFS_MAX_VOLUME_NAME + 1)) {
+ ret = -EFAULT;
+ goto out_drop_write;
+ }
+
+ len = strnlen(label, NILFS_MAX_VOLUME_NAME + 1);
+ if (len > NILFS_MAX_VOLUME_NAME) {
+ nilfs_err(sb, "unable to set label with more than %zu bytes",
+ NILFS_MAX_VOLUME_NAME);
+ ret = -EINVAL;
+ goto out_drop_write;
+ }
+
+ down_write(&nilfs->ns_sem);
+ sbp = nilfs_prepare_super(sb, false);
+ if (unlikely(!sbp)) {
+ ret = -EIO;
+ goto out_unlock;
+ }
+
+ strtomem_pad(sbp[0]->s_volume_name, label, 0);
+ if (sbp[1])
+ strtomem_pad(sbp[1]->s_volume_name, label, 0);
+
+ ret = nilfs_commit_super(sb, NILFS_SB_COMMIT_ALL);
+
+out_unlock:
+ up_write(&nilfs->ns_sem);
+out_drop_write:
+ mnt_drop_write_file(filp);
+ return ret;
+}
+
long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
{
struct inode *inode = file_inode(filp);
@@ -1334,6 +1396,8 @@ long nilfs_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
return nilfs_ioctl_trim_fs(inode, argp);
case FS_IOC_GETFSLABEL:
return nilfs_ioctl_get_fslabel(inode->i_sb, argp);
+ case FS_IOC_SETFSLABEL:
+ return nilfs_ioctl_set_fslabel(inode->i_sb, filp, argp);
default:
return -ENOTTY;
}
@@ -1361,6 +1425,7 @@ long nilfs_compat_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
case NILFS_IOCTL_SET_ALLOC_RANGE:
case FITRIM:
case FS_IOC_GETFSLABEL:
+ case FS_IOC_SETFSLABEL:
break;
default:
return -ENOIOCTLCMD;
--
2.34.1
