Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/sage/ceph...

[~andy/linux] / arch / x86 / xen / grant-table.c

diff --git a/arch/x86/xen/grant-table.c b/arch/x86/xen/grant-table.c
index 5a40d24ba3316b85b42e5ef5d00280b89a2033b9..3a5f55d51907aa16a8a58acfce22436f56366951 100644 (file)
--- a/arch/x86/xen/grant-table.c
+++ b/arch/x86/xen/grant-table.c
@@ -54,6 +54,20 @@ static int map_pte_fn(pte_t *pte, struct page *pmd_page,
        return 0;
 }
 
+/*
+ * 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;
+
+       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)
 {
@@ -64,10 +78,10 @@ static int unmap_pte_fn(pte_t *pte, struct page *pmd_page,
 
 int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
                           unsigned long max_nr_gframes,
-                          struct grant_entry **__shared)
+                          void **__shared)
 {
        int rc;
-       struct grant_entry *shared = *__shared;
+       void *shared = *__shared;
 
        if (shared == NULL) {
                struct vm_struct *area =
@@ -83,8 +97,30 @@ int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes,
        return rc;
 }
 
-void arch_gnttab_unmap_shared(struct grant_entry *shared,
-                             unsigned long nr_gframes)
+int arch_gnttab_map_status(uint64_t *frames, unsigned long nr_gframes,
+                          unsigned long max_nr_gframes,
+                          grant_status_t **__shared)
+{
+       int rc;
+       grant_status_t *shared = *__shared;
+
+       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;
+       }
+
+       rc = apply_to_page_range(&init_mm, (unsigned long)shared,
+                                PAGE_SIZE * nr_gframes,
+                                map_pte_fn_status, &frames);
+       return rc;
+}
+
+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);