1 files changed, 64 insertions, 0 deletions
diff --git a/arch/x86/xen/grant-table.c b/arch/x86/xen/grant-table.c
index 3a5f55d..c985835 100644
--- a/arch/x86/xen/grant-table.c
+++ b/arch/x86/xen/grant-table.c
@@ -125,3 +125,67 @@ void arch_gnttab_unmap(void *shared, unsigned long nr_gframes)
 	apply_to_page_range(&init_mm, (unsigned long)shared,
 			    PAGE_SIZE * nr_gframes, unmap_pte_fn, NULL);
 }
+#ifdef CONFIG_XEN_PVH
+#include <xen/balloon.h>
+#include <xen/events.h>
+#include <xen/xen.h>
+#include <linux/slab.h>
+static int __init xlated_setup_gnttab_pages(void)
+{
+	struct page **pages;
+	xen_pfn_t *pfns;
+	int rc;
+	unsigned int i;
+	unsigned long nr_grant_frames = gnttab_max_grant_frames();
+
+	BUG_ON(nr_grant_frames == 0);
+	pages = kcalloc(nr_grant_frames, sizeof(pages[0]), GFP_KERNEL);
+	if (!pages)
+		return -ENOMEM;
+
+	pfns = kcalloc(nr_grant_frames, sizeof(pfns[0]), GFP_KERNEL);
+	if (!pfns) {
+		kfree(pages);
+		return -ENOMEM;
+	}
+	rc = alloc_xenballooned_pages(nr_grant_frames, pages, 0 /* lowmem */);
+	if (rc) {
+		pr_warn("%s Couldn't balloon alloc %ld pfns rc:%d\n", __func__,
+			nr_grant_frames, rc);
+		kfree(pages);
+		kfree(pfns);
+		return rc;
+	}
+	for (i = 0; i < nr_grant_frames; i++)
+		pfns[i] = page_to_pfn(pages[i]);
+
+	rc = arch_gnttab_map_shared(pfns, nr_grant_frames, nr_grant_frames,
+				    &xen_auto_xlat_grant_frames.vaddr);
+
+	if (rc) {
+		pr_warn("%s Couldn't map %ld pfns rc:%d\n", __func__,
+			nr_grant_frames, rc);
+		free_xenballooned_pages(nr_grant_frames, pages);
+		kfree(pages);
+		kfree(pfns);
+		return rc;
+	}
+	kfree(pages);
+
+	xen_auto_xlat_grant_frames.pfn = pfns;
+	xen_auto_xlat_grant_frames.count = nr_grant_frames;
+
+	return 0;
+}
+
+static int __init xen_pvh_gnttab_setup(void)
+{
+	if (!xen_pvh_domain())
+		return -ENODEV;
+
+	return xlated_setup_gnttab_pages();
+}
+/* Call it _before_ __gnttab_init as we need to initialize the
+ * xen_auto_xlat_grant_frames first. */
+core_initcall(xen_pvh_gnttab_setup);
+#endif