diff --git a/drivers/xen/gntdev.c b/drivers/xen/gntdev.c index 20c65771017df5..d5bb1a33d0a3fc 100644 --- a/drivers/xen/gntdev.c +++ b/drivers/xen/gntdev.c @@ -93,6 +93,7 @@ struct grant_map { struct gnttab_map_grant_ref *kmap_ops; struct gnttab_unmap_grant_ref *kunmap_ops; struct page **pages; + unsigned long pages_vm_start; }; static int unmap_grant_pages(struct grant_map *map, int offset, int pages); @@ -446,9 +447,18 @@ static void gntdev_vma_close(struct vm_area_struct *vma) gntdev_put_map(priv, map); } +static struct page *gntdev_vma_find_special_page(struct vm_area_struct *vma, + unsigned long addr) +{ + struct grant_map *map = vma->vm_private_data; + + return map->pages[(addr - map->pages_vm_start) >> PAGE_SHIFT]; +} + static struct vm_operations_struct gntdev_vmops = { .open = gntdev_vma_open, .close = gntdev_vma_close, + .find_special_page = gntdev_vma_find_special_page, }; /* ------------------------------------------------------------------ */ @@ -874,6 +884,7 @@ static int gntdev_mmap(struct file *flip, struct vm_area_struct *vma) set_grant_ptes_as_special, NULL); } #endif + map->pages_vm_start = vma->vm_start; } return 0;