1 files changed, 62 insertions, 0 deletions

diff --git a/arch/x86/xen/grant-table.c b/arch/x86/xen/grant-table.c
index 3a5f55d51907..2d719799fd6a 100644
--- a/arch/x86/xen/grant-table.c
+++ b/arch/x86/xen/grant-table.c
@@ -125,3 +125,65 @@ 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 <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);
+
+        kfree(pages);
+        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(pfns);
+                return rc;
+        }
+
+        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