x86/xen: use vmap() to map grant table pages in PVH guests

[cascardo/linux.git] / arch / x86 / xen / grant-table.c

diff --git a/arch/x86/xen/grant-table.c b/arch/x86/xen/grant-table.c
index ebfa9b2..1580e7a 100644 (file)
--- a/arch/x86/xen/grant-table.c
+++ b/arch/x86/xen/grant-table.c
@@ -49,7 +49,7 @@
 static struct gnttab_vm_area {
        struct vm_struct *area;
        pte_t **ptes;
-} gnttab_shared_vm_area, gnttab_status_vm_area;
+} gnttab_shared_vm_area;
 
 int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
                           unsigned long max_nr_gframes,
@@ -73,43 +73,16 @@ int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
        return 0;
 }
 
-int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
-                          unsigned long max_nr_gframes,
-                          grant_status_t **__shared)
-{
-       grant_status_t *shared = *__shared;
-       unsigned long addr;
-       unsigned long i;
-
-       if (shared == NULL)
-               *__shared = shared = gnttab_status_vm_area.area->addr;
-
-       addr = (unsigned long)shared;
-
-       for (i = 0; i < nr_gframes; i++) {
-               set_pte_at(&init_mm, addr, gnttab_status_vm_area.ptes[i],
-                          mfn_pte(frames[i], PAGE_KERNEL));
-               addr += PAGE_SIZE;
-       }
-
-       return 0;
-}
-
 void arch_gnttab_unmap(void *shared, unsigned long nr_gframes)
 {
-       pte_t **ptes;
        unsigned long addr;
        unsigned long i;
 
-       if (shared == gnttab_status_vm_area.area->addr)
-               ptes = gnttab_status_vm_area.ptes;
-       else
-               ptes = gnttab_shared_vm_area.ptes;
-
        addr = (unsigned long)shared;
 
        for (i = 0; i < nr_gframes; i++) {
-               set_pte_at(&init_mm, addr, ptes[i], __pte(0));
+               set_pte_at(&init_mm, addr, gnttab_shared_vm_area.ptes[i],
+                          __pte(0));
                addr += PAGE_SIZE;
        }
 }
@@ -129,35 +102,12 @@ static int arch_gnttab_valloc(struct gnttab_vm_area *area, unsigned nr_frames)
        return 0;
 }
 
-static void arch_gnttab_vfree(struct gnttab_vm_area *area)
+int arch_gnttab_init(unsigned long nr_shared)
 {
-       free_vm_area(area->area);
-       kfree(area->ptes);
-}
-
-int arch_gnttab_init(unsigned long nr_shared, unsigned long nr_status)
-{
-       int ret;
-
        if (!xen_pv_domain())
                return 0;
 
-       ret = arch_gnttab_valloc(&gnttab_shared_vm_area, nr_shared);
-       if (ret < 0)
-               return ret;
-
-       /*
-        * Always allocate the space for the status frames in case
-        * we're migrated to a host with V2 support.
-        */
-       ret = arch_gnttab_valloc(&gnttab_status_vm_area, nr_status);
-       if (ret < 0)
-               goto err;
-
-       return 0;
-  err:
-       arch_gnttab_vfree(&gnttab_shared_vm_area);
-       return -ENOMEM;
+       return arch_gnttab_valloc(&gnttab_shared_vm_area, nr_shared);
 }
 
 #ifdef CONFIG_XEN_PVH
@@ -168,6 +118,7 @@ static int __init xlated_setup_gnttab_pages(void)
 {
        struct page **pages;
        xen_pfn_t *pfns;
+       void *vaddr;
        int rc;
        unsigned int i;
        unsigned long nr_grant_frames = gnttab_max_grant_frames();
@@ -193,21 +144,20 @@ static int __init xlated_setup_gnttab_pages(void)
        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) {
+       vaddr = vmap(pages, nr_grant_frames, 0, PAGE_KERNEL);
+       if (!vaddr) {
                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;
+               return -ENOMEM;
        }
        kfree(pages);
 
        xen_auto_xlat_grant_frames.pfn = pfns;
        xen_auto_xlat_grant_frames.count = nr_grant_frames;
+       xen_auto_xlat_grant_frames.vaddr = vaddr;
 
        return 0;
 }