diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c index 3a970604308f..d9476ff877b8 100644 --- a/kernel/power/snapshot.c +++ b/kernel/power/snapshot.c @@ -74,6 +74,22 @@ void __init hibernate_image_size_init(void) */ struct pbe *restore_pblist; +/* struct linked_page is used to build chains of pages */ + +#define LINKED_PAGE_DATA_SIZE (PAGE_SIZE - sizeof(void *)) + +struct linked_page { + struct linked_page *next; + char data[LINKED_PAGE_DATA_SIZE]; +} __packed; + +/* + * List of "safe" pages (ie. pages that were not used by the image kernel + * before hibernation) that may be used as temporary storage for image kernel + * memory contents. + */ +static struct linked_page *safe_pages_list; + /* Pointer to an auxiliary buffer (1 page) */ static void *buffer; @@ -113,9 +129,21 @@ static void *get_image_page(gfp_t gfp_mask, int safe_needed) return res; } +static void *__get_safe_page(gfp_t gfp_mask) +{ + if (safe_pages_list) { + void *ret = safe_pages_list; + + safe_pages_list = safe_pages_list->next; + memset(ret, 0, PAGE_SIZE); + return ret; + } + return get_image_page(gfp_mask, PG_SAFE); +} + unsigned long get_safe_page(gfp_t gfp_mask) { - return (unsigned long)get_image_page(gfp_mask, PG_SAFE); + return (unsigned long)__get_safe_page(gfp_mask); } static struct page *alloc_image_page(gfp_t gfp_mask) @@ -150,15 +178,6 @@ static inline void free_image_page(void *addr, int clear_nosave_free) __free_page(page); } -/* struct linked_page is used to build chains of pages */ - -#define LINKED_PAGE_DATA_SIZE (PAGE_SIZE - sizeof(void *)) - -struct linked_page { - struct linked_page *next; - char data[LINKED_PAGE_DATA_SIZE]; -} __packed; - static inline void free_list_of_pages(struct linked_page *list, int clear_page_nosave) { @@ -208,7 +227,8 @@ static void *chain_alloc(struct chain_allocator *ca, unsigned int size) if (LINKED_PAGE_DATA_SIZE - ca->used_space < size) { struct linked_page *lp; - lp = get_image_page(ca->gfp_mask, ca->safe_needed); + lp = ca->safe_needed ? __get_safe_page(ca->gfp_mask) : + get_image_page(ca->gfp_mask, PG_ANY); if (!lp) return NULL; @@ -2104,11 +2124,6 @@ static int unpack_orig_pfns(unsigned long *buf, struct memory_bitmap *bm) return 0; } -/* List of "safe" pages that may be used to store data loaded from the suspend - * image - */ -static struct linked_page *safe_pages_list; - #ifdef CONFIG_HIGHMEM /* struct highmem_pbe is used for creating the list of highmem pages that * should be restored atomically during the resume from disk, because the page @@ -2334,7 +2349,7 @@ static int prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) { unsigned int nr_pages, nr_highmem; - struct linked_page *sp_list, *lp; + struct linked_page *lp; int error; /* If there is no highmem, the buffer will not be necessary */ @@ -2362,9 +2377,9 @@ prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) * NOTE: This way we make sure there will be enough safe pages for the * chain_alloc() in get_buffer(). It is a bit wasteful, but * nr_copy_pages cannot be greater than 50% of the memory anyway. + * + * nr_copy_pages cannot be less than allocated_unsafe_pages too. */ - sp_list = NULL; - /* nr_copy_pages cannot be lesser than allocated_unsafe_pages */ nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; nr_pages = DIV_ROUND_UP(nr_pages, PBES_PER_LINKED_PAGE); while (nr_pages > 0) { @@ -2373,12 +2388,11 @@ prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) error = -ENOMEM; goto Free; } - lp->next = sp_list; - sp_list = lp; + lp->next = safe_pages_list; + safe_pages_list = lp; nr_pages--; } /* Preallocate memory for the image */ - safe_pages_list = NULL; nr_pages = nr_copy_pages - nr_highmem - allocated_unsafe_pages; while (nr_pages > 0) { lp = (struct linked_page *)get_zeroed_page(GFP_ATOMIC); @@ -2396,12 +2410,6 @@ prepare_image(struct memory_bitmap *new_bm, struct memory_bitmap *bm) swsusp_set_page_free(virt_to_page(lp)); nr_pages--; } - /* Free the reserved safe pages so that chain_alloc() can use them */ - while (sp_list) { - lp = sp_list->next; - free_image_page(sp_list, PG_UNSAFE_CLEAR); - sp_list = lp; - } return 0; Free: @@ -2491,6 +2499,8 @@ int snapshot_write_next(struct snapshot_handle *handle) if (error) return error; + safe_pages_list = NULL; + error = memory_bm_create(©_bm, GFP_ATOMIC, PG_ANY); if (error) return error;