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path: root/fs/xfs/xfs_ioctl.c
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Diffstat (limited to 'fs/xfs/xfs_ioctl.c')
-rw-r--r--fs/xfs/xfs_ioctl.c89
1 files changed, 88 insertions, 1 deletions
diff --git a/fs/xfs/xfs_ioctl.c b/fs/xfs/xfs_ioctl.c
index 89fb1eb80aae..5dd9e22b4a4c 100644
--- a/fs/xfs/xfs_ioctl.c
+++ b/fs/xfs/xfs_ioctl.c
@@ -1103,7 +1103,8 @@ xfs_ioctl_setattr_dax_invalidate(
if (fa->fsx_xflags & FS_XFLAG_DAX) {
if (!(S_ISREG(inode->i_mode) || S_ISDIR(inode->i_mode)))
return -EINVAL;
- if (bdev_dax_supported(sb, sb->s_blocksize) < 0)
+ if (!bdev_dax_supported(xfs_find_bdev_for_inode(VFS_I(ip)),
+ sb->s_blocksize))
return -EINVAL;
}
@@ -1811,6 +1812,88 @@ xfs_ioc_swapext(
return error;
}
+static int
+xfs_ioc_getlabel(
+ struct xfs_mount *mp,
+ char __user *user_label)
+{
+ struct xfs_sb *sbp = &mp->m_sb;
+ char label[XFSLABEL_MAX + 1];
+
+ /* Paranoia */
+ BUILD_BUG_ON(sizeof(sbp->sb_fname) > FSLABEL_MAX);
+
+ spin_lock(&mp->m_sb_lock);
+ strncpy(label, sbp->sb_fname, sizeof(sbp->sb_fname));
+ spin_unlock(&mp->m_sb_lock);
+
+ /* xfs on-disk label is 12 chars, be sure we send a null to user */
+ label[XFSLABEL_MAX] = '\0';
+ if (copy_to_user(user_label, label, sizeof(sbp->sb_fname)))
+ return -EFAULT;
+ return 0;
+}
+
+static int
+xfs_ioc_setlabel(
+ struct file *filp,
+ struct xfs_mount *mp,
+ char __user *newlabel)
+{
+ struct xfs_sb *sbp = &mp->m_sb;
+ char label[XFSLABEL_MAX + 1];
+ size_t len;
+ int error;
+
+ if (!capable(CAP_SYS_ADMIN))
+ return -EPERM;
+ /*
+ * The generic ioctl allows up to FSLABEL_MAX chars, but XFS is much
+ * smaller, at 12 bytes. We copy one more to be sure we find the
+ * (required) NULL character to test the incoming label length.
+ * NB: The on disk label doesn't need to be null terminated.
+ */
+ if (copy_from_user(label, newlabel, XFSLABEL_MAX + 1))
+ return -EFAULT;
+ len = strnlen(label, XFSLABEL_MAX + 1);
+ if (len > sizeof(sbp->sb_fname))
+ return -EINVAL;
+
+ error = mnt_want_write_file(filp);
+ if (error)
+ return error;
+
+ spin_lock(&mp->m_sb_lock);
+ memset(sbp->sb_fname, 0, sizeof(sbp->sb_fname));
+ strncpy(sbp->sb_fname, label, sizeof(sbp->sb_fname));
+ spin_unlock(&mp->m_sb_lock);
+
+ /*
+ * Now we do several things to satisfy userspace.
+ * In addition to normal logging of the primary superblock, we also
+ * immediately write these changes to sector zero for the primary, then
+ * update all backup supers (as xfs_db does for a label change), then
+ * invalidate the block device page cache. This is so that any prior
+ * buffered reads from userspace (i.e. from blkid) are invalidated,
+ * and userspace will see the newly-written label.
+ */
+ error = xfs_sync_sb_buf(mp);
+ if (error)
+ goto out;
+ /*
+ * growfs also updates backup supers so lock against that.
+ */
+ mutex_lock(&mp->m_growlock);
+ error = xfs_update_secondary_sbs(mp);
+ mutex_unlock(&mp->m_growlock);
+
+ invalidate_bdev(mp->m_ddev_targp->bt_bdev);
+
+out:
+ mnt_drop_write_file(filp);
+ return error;
+}
+
/*
* Note: some of the ioctl's return positive numbers as a
* byte count indicating success, such as readlink_by_handle.
@@ -1834,6 +1917,10 @@ xfs_file_ioctl(
switch (cmd) {
case FITRIM:
return xfs_ioc_trim(mp, arg);
+ case FS_IOC_GETFSLABEL:
+ return xfs_ioc_getlabel(mp, arg);
+ case FS_IOC_SETFSLABEL:
+ return xfs_ioc_setlabel(filp, mp, arg);
case XFS_IOC_ALLOCSP:
case XFS_IOC_FREESP:
case XFS_IOC_RESVSP: