Merge remote-tracking branches 'asoc/topic/intel', 'asoc/topic/kirkwood', 'asoc/topic...

[linux-2.6-block.git] / arch / x86 / xen / grant-table.c

diff --git a/arch/x86/xen/grant-table.c b/arch/x86/xen/grant-table.c
index c985835885802a69ef0b255e36c81484026ab227..ebfa9b2c871db56a2a6a631e5502acdf96e2032e 100644 (file)
--- a/arch/x86/xen/grant-table.c
+++ b/arch/x86/xen/grant-table.c
@@ -36,99 +36,133 @@
 
 #include <linux/sched.h>
 #include <linux/mm.h>
+#include <linux/slab.h>
 #include <linux/vmalloc.h>
 
 #include <xen/interface/xen.h>
 #include <xen/page.h>
 #include <xen/grant_table.h>
+#include <xen/xen.h>
 
 #include <asm/pgtable.h>
 
-static int map_pte_fn(pte_t *pte, struct page *pmd_page,
-                     unsigned long addr, void *data)
+static struct gnttab_vm_area {
+       struct vm_struct *area;
+       pte_t **ptes;
+} gnttab_shared_vm_area, gnttab_status_vm_area;
+
+int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
+                          unsigned long max_nr_gframes,
+                          void **__shared)
 {
-       unsigned long **frames = (unsigned long **)data;
+       void *shared = *__shared;
+       unsigned long addr;
+       unsigned long i;
 
-       set_pte_at(&init_mm, addr, pte, mfn_pte((*frames)[0], PAGE_KERNEL));
-       (*frames)++;
-       return 0;
-}
+       if (shared == NULL)
+               *__shared = shared = gnttab_shared_vm_area.area->addr;
 
-/*
- * This function is used to map shared frames to store grant status. It is
- * different from map_pte_fn above, the frames type here is uint64_t.
- */
-static int map_pte_fn_status(pte_t *pte, struct page *pmd_page,
-                            unsigned long addr, void *data)
-{
-       uint64_t **frames = (uint64_t **)data;
+       addr = (unsigned long)shared;
+
+       for (i = 0; i < nr_gframes; i++) {
+               set_pte_at(&init_mm, addr, gnttab_shared_vm_area.ptes[i],
+                          mfn_pte(frames[i], PAGE_KERNEL));
+               addr += PAGE_SIZE;
+       }
 
-       set_pte_at(&init_mm, addr, pte, mfn_pte((*frames)[0], PAGE_KERNEL));
-       (*frames)++;
        return 0;
 }
 
-static int unmap_pte_fn(pte_t *pte, struct page *pmd_page,
-                       unsigned long addr, void *data)
+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;
+       }
 
-       set_pte_at(&init_mm, addr, pte, __pte(0));
        return 0;
 }
 
-int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
-                          unsigned long max_nr_gframes,
-                          void **__shared)
+void arch_gnttab_unmap(void *shared, unsigned long nr_gframes)
 {
-       int rc;
-       void *shared = *__shared;
+       pte_t **ptes;
+       unsigned long addr;
+       unsigned long i;
 
-       if (shared == NULL) {
-               struct vm_struct *area =
-                       alloc_vm_area(PAGE_SIZE * max_nr_gframes, NULL);
-               BUG_ON(area == NULL);
-               shared = area->addr;
-               *__shared = shared;
-       }
+       if (shared == gnttab_status_vm_area.area->addr)
+               ptes = gnttab_status_vm_area.ptes;
+       else
+               ptes = gnttab_shared_vm_area.ptes;
 
-       rc = apply_to_page_range(&init_mm, (unsigned long)shared,
-                                PAGE_SIZE * nr_gframes,
-                                map_pte_fn, &frames);
-       return rc;
+       addr = (unsigned long)shared;
+
+       for (i = 0; i < nr_gframes; i++) {
+               set_pte_at(&init_mm, addr, ptes[i], __pte(0));
+               addr += PAGE_SIZE;
+       }
 }
 
-int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
-                          unsigned long max_nr_gframes,
-                          grant_status_t **__shared)
+static int arch_gnttab_valloc(struct gnttab_vm_area *area, unsigned nr_frames)
 {
-       int rc;
-       grant_status_t *shared = *__shared;
+       area->ptes = kmalloc(sizeof(pte_t *) * nr_frames, GFP_KERNEL);
+       if (area->ptes == NULL)
+               return -ENOMEM;
 
-       if (shared == NULL) {
-               /* No need to pass in PTE as we are going to do it
-                * in apply_to_page_range anyhow. */
-               struct vm_struct *area =
-                       alloc_vm_area(PAGE_SIZE * max_nr_gframes, NULL);
-               BUG_ON(area == NULL);
-               shared = area->addr;
-               *__shared = shared;
+       area->area = alloc_vm_area(PAGE_SIZE * nr_frames, area->ptes);
+       if (area->area == NULL) {
+               kfree(area->ptes);
+               return -ENOMEM;
        }
 
-       rc = apply_to_page_range(&init_mm, (unsigned long)shared,
-                                PAGE_SIZE * nr_gframes,
-                                map_pte_fn_status, &frames);
-       return rc;
+       return 0;
 }
 
-void arch_gnttab_unmap(void *shared, unsigned long nr_gframes)
+static void arch_gnttab_vfree(struct gnttab_vm_area *area)
+{
+       free_vm_area(area->area);
+       kfree(area->ptes);
+}
+
+int arch_gnttab_init(unsigned long nr_shared, unsigned long nr_status)
 {
-       apply_to_page_range(&init_mm, (unsigned long)shared,
-                           PAGE_SIZE * nr_gframes, unmap_pte_fn, NULL);
+       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;
 }
+
 #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)
 {