diff options
Diffstat (limited to 'arch/x86/xen')
| -rw-r--r-- | arch/x86/xen/grant-table.c | 39 |
1 files changed, 38 insertions, 1 deletions
diff --git a/arch/x86/xen/grant-table.c b/arch/x86/xen/grant-table.c index c6ab2e7ca3a6..65160a8a0ba3 100644 --- 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) { @@ -83,7 +97,30 @@ int arch_gnttab_map_shared(unsigned long *frames, unsigned long nr_gframes, return rc; } -void arch_gnttab_unmap_shared(void *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); |