vhost_vdpa: disable doorbell mapping for !MMU

There could be ways to support doorbell mapping with !MMU, but things
like pgprot_noncached are not universally supported.
Fixable, but just disable this for now.

Signed-off-by: Michael S. Tsirkin <mst@redhat.com>

diff --git a/drivers/vhost/vdpa.c b/drivers/vhost/vdpa.c
index 3d163ec..6ca7660 100644 (file)
--- a/drivers/vhost/vdpa.c
+++ b/drivers/vhost/vdpa.c
@@ -740,6 +740,7 @@ static int vhost_vdpa_release(struct inode *inode, struct file *filep)
        return 0;
 }
 
+#ifdef CONFIG_MMU
 static vm_fault_t vhost_vdpa_fault(struct vm_fault *vmf)
 {
        struct vhost_vdpa *v = vmf->vma->vm_file->private_data;
@@ -796,6 +797,7 @@ static int vhost_vdpa_mmap(struct file *file, struct vm_area_struct *vma)
        vma->vm_ops = &vhost_vdpa_vm_ops;
        return 0;
 }
+#endif /* CONFIG_MMU */
 
 static const struct file_operations vhost_vdpa_fops = {
        .owner          = THIS_MODULE,
@@ -803,7 +805,9 @@ static const struct file_operations vhost_vdpa_fops = {
        .release        = vhost_vdpa_release,
        .write_iter     = vhost_vdpa_chr_write_iter,
        .unlocked_ioctl = vhost_vdpa_unlocked_ioctl,
+#ifdef CONFIG_MMU
        .mmap           = vhost_vdpa_mmap,
+#endif /* CONFIG_MMU */
        .compat_ioctl   = compat_ptr_ioctl,
 };