PM / hibernate: Simplify mark_unsafe_pages()
Rework mark_unsafe_pages() to use a simpler method of clearing
all bits in free_pages_map and to set the bits for the "unsafe"
pages (ie. pages that were used by the image kernel before
hibernation) with the help of duplicate_memory_bitmap().
For this purpose, move the pfn_valid() check from mark_unsafe_pages()
to unpack_orig_pfns() where the "unsafe" pages are discovered.
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index d9476ff..39bbad5 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -2019,44 +2019,8 @@
return PAGE_SIZE;
}
-/**
- * mark_unsafe_pages - mark the pages that cannot be used for storing
- * the image during resume, because they conflict with the pages that
- * had been used before suspend
- */
-
-static int mark_unsafe_pages(struct memory_bitmap *bm)
-{
- struct zone *zone;
- unsigned long pfn, max_zone_pfn;
-
- /* Clear page flags */
- for_each_populated_zone(zone) {
- max_zone_pfn = zone_end_pfn(zone);
- for (pfn = zone->zone_start_pfn; pfn < max_zone_pfn; pfn++)
- if (pfn_valid(pfn))
- swsusp_unset_page_free(pfn_to_page(pfn));
- }
-
- /* Mark pages that correspond to the "original" pfns as "unsafe" */
- memory_bm_position_reset(bm);
- do {
- pfn = memory_bm_next_pfn(bm);
- if (likely(pfn != BM_END_OF_MAP)) {
- if (likely(pfn_valid(pfn)))
- swsusp_set_page_free(pfn_to_page(pfn));
- else
- return -EFAULT;
- }
- } while (pfn != BM_END_OF_MAP);
-
- allocated_unsafe_pages = 0;
-
- return 0;
-}
-
-static void
-duplicate_memory_bitmap(struct memory_bitmap *dst, struct memory_bitmap *src)
+static void duplicate_memory_bitmap(struct memory_bitmap *dst,
+ struct memory_bitmap *src)
{
unsigned long pfn;
@@ -2068,6 +2032,30 @@
}
}
+/**
+ * mark_unsafe_pages - mark the pages that cannot be used for storing
+ * the image during resume, because they conflict with the pages that
+ * had been used before suspend
+ */
+
+static void mark_unsafe_pages(struct memory_bitmap *bm)
+{
+ unsigned long pfn;
+
+ /* Clear the "free"/"unsafe" bit for all PFNs */
+ memory_bm_position_reset(free_pages_map);
+ pfn = memory_bm_next_pfn(free_pages_map);
+ while (pfn != BM_END_OF_MAP) {
+ memory_bm_clear_current(free_pages_map);
+ pfn = memory_bm_next_pfn(free_pages_map);
+ }
+
+ /* Mark pages that correspond to the "original" PFNs as "unsafe" */
+ duplicate_memory_bitmap(free_pages_map, bm);
+
+ allocated_unsafe_pages = 0;
+}
+
static int check_header(struct swsusp_info *info)
{
char *reason;
@@ -2115,7 +2103,7 @@
/* Extract and buffer page key for data page (s390 only). */
page_key_memorize(buf + j);
- if (memory_bm_pfn_present(bm, buf[j]))
+ if (pfn_valid(buf[j]) && memory_bm_pfn_present(bm, buf[j]))
memory_bm_set_bit(bm, buf[j]);
else
return -EFAULT;
@@ -2357,9 +2345,7 @@
buffer = NULL;
nr_highmem = count_highmem_image_pages(bm);
- error = mark_unsafe_pages(bm);
- if (error)
- goto Free;
+ mark_unsafe_pages(bm);
error = memory_bm_create(new_bm, GFP_ATOMIC, PG_SAFE);
if (error)