5 files changed, 126 insertions, 37 deletions

diff --git a/include/linux/suspend.h b/include/linux/suspend.h
index 33bbaea23aaf..5dc94e777fab 100644
--- a/include/linux/suspend.h
+++ b/include/linux/suspend.h
@@ -73,6 +73,6 @@ unsigned long get_safe_page(gfp_t gfp_mask);
  * XXX: We try to keep some more pages free so that I/O operations succeed
  * without paging. Might this be more?
  */
-#define PAGES_FOR_IO    512
+#define PAGES_FOR_IO    1024
 
 #endif /* _LINUX_SWSUSP_H */
diff --git a/kernel/power/disk.c b/kernel/power/disk.c
index 76a5131b0e80..9e51cdf7b78d 100644
--- a/kernel/power/disk.c
+++ b/kernel/power/disk.c
@@ -24,6 +24,7 @@
 
 extern suspend_disk_method_t pm_disk_mode;
 
+extern int swsusp_shrink_memory(void);
 extern int swsusp_suspend(void);
 extern int swsusp_write(struct pbe *pblist, unsigned int nr_pages);
 extern int swsusp_check(void);
@@ -73,31 +74,6 @@ static void power_down(suspend_disk_method_t mode)
 static int in_suspend __nosavedata = 0;
 
 
-/**
- *      free_some_memory -  Try to free as much memory as possible
- *
- *      ... but do not OOM-kill anyone
- *
- *      Notice: all userland should be stopped at this point, or
- *      livelock is possible.
- */
-
-static void free_some_memory(void)
-{
-        unsigned int i = 0;
-        unsigned int tmp;
-        unsigned long pages = 0;
-        char *p = "-\\|/";
-
-        printk("Freeing memory...  ");
-        while ((tmp = shrink_all_memory(10000))) {
-                pages += tmp;
-                printk("\b%c", p[i++ % 4]);
-        }
-        printk("\bdone (%li pages freed)\n", pages);
-}
-
-
 static inline void platform_finish(void)
 {
         if (pm_disk_mode == PM_DISK_PLATFORM) {
@@ -127,8 +103,8 @@ static int prepare_processes(void)
         }
 
         /* Free memory before shutting down devices. */
-        free_some_memory();
-        return 0;
+        if (!(error = swsusp_shrink_memory()))
+                return 0;
 thaw:
         thaw_processes();
         enable_nonboot_cpus();
diff --git a/kernel/power/power.h b/kernel/power/power.h
index 977877c6dcfc..acdc83b3d890 100644
--- a/kernel/power/power.h
+++ b/kernel/power/power.h
@@ -49,18 +49,26 @@ extern void thaw_processes(void);
 extern int pm_prepare_console(void);
 extern void pm_restore_console(void);
 
-
 /* References to section boundaries */
 extern const void __nosave_begin, __nosave_end;
 
 extern unsigned int nr_copy_pages;
-extern suspend_pagedir_t *pagedir_nosave;
-extern suspend_pagedir_t *pagedir_save;
+extern struct pbe *pagedir_nosave;
+
+/*
+ * This compilation switch determines the way in which memory will be freed
+ * during suspend.  If defined, only as much memory will be freed as needed
+ * to complete the suspend, which will make it go faster.  Otherwise, the
+ * largest possible amount of memory will be freed.
+ */
+#define FAST_FREE       1
 
 extern asmlinkage int swsusp_arch_suspend(void);
 extern asmlinkage int swsusp_arch_resume(void);
 
+extern unsigned int count_data_pages(void);
 extern void free_pagedir(struct pbe *pblist);
+extern void release_eaten_pages(void);
 extern struct pbe *alloc_pagedir(unsigned nr_pages, gfp_t gfp_mask, int safe_needed);
 extern void swsusp_free(void);
 extern int alloc_data_pages(struct pbe *pblist, gfp_t gfp_mask, int safe_needed);
diff --git a/kernel/power/snapshot.c b/kernel/power/snapshot.c
index 152d56cdf017..e80d282dbf58 100644
--- a/kernel/power/snapshot.c
+++ b/kernel/power/snapshot.c
@@ -37,6 +37,31 @@ struct pbe *pagedir_nosave;
 unsigned int nr_copy_pages;
 
 #ifdef CONFIG_HIGHMEM
+unsigned int count_highmem_pages(void)
+{
+        struct zone *zone;
+        unsigned long zone_pfn;
+        unsigned int n = 0;
+
+        for_each_zone (zone)
+                if (is_highmem(zone)) {
+                        mark_free_pages(zone);
+                        for (zone_pfn = 0; zone_pfn < zone->spanned_pages; zone_pfn++) {
+                                struct page *page;
+                                unsigned long pfn = zone_pfn + zone->zone_start_pfn;
+                                if (!pfn_valid(pfn))
+                                        continue;
+                                page = pfn_to_page(pfn);
+                                if (PageReserved(page))
+                                        continue;
+                                if (PageNosaveFree(page))
+                                        continue;
+                                n++;
+                        }
+                }
+        return n;
+}
+
 struct highmem_page {
         char *data;
         struct page *page;
@@ -152,17 +177,15 @@ static int saveable(struct zone *zone, unsigned long *zone_pfn)
         BUG_ON(PageReserved(page) && PageNosave(page));
         if (PageNosave(page))
                 return 0;
-        if (PageReserved(page) && pfn_is_nosave(pfn)) {
-                pr_debug("[nosave pfn 0x%lx]", pfn);
+        if (PageReserved(page) && pfn_is_nosave(pfn))
                 return 0;
-        }
         if (PageNosaveFree(page))
                 return 0;
 
         return 1;
 }
 
-static unsigned count_data_pages(void)
+unsigned int count_data_pages(void)
 {
         struct zone *zone;
         unsigned long zone_pfn;
@@ -267,6 +290,35 @@ static inline void create_pbe_list(struct pbe *pblist, unsigned int nr_pages)
 }
 
 /**
+ *      On resume it is necessary to trace and eventually free the unsafe
+ *      pages that have been allocated, because they are needed for I/O
+ *      (on x86-64 we likely will "eat" these pages once again while
+ *      creating the temporary page translation tables)
+ */
+
+struct eaten_page {
+        struct eaten_page *next;
+        char padding[PAGE_SIZE - sizeof(void *)];
+};
+
+static struct eaten_page *eaten_pages = NULL;
+
+void release_eaten_pages(void)
+{
+        struct eaten_page *p, *q;
+
+        p = eaten_pages;
+        while (p) {
+                q = p->next;
+                /* We don't want swsusp_free() to free this page again */
+                ClearPageNosave(virt_to_page(p));
+                free_page((unsigned long)p);
+                p = q;
+        }
+        eaten_pages = NULL;
+}
+
+/**
  *      @safe_needed - on resume, for storing the PBE list and the image,
  *      we can only use memory pages that do not conflict with the pages
  *      which had been used before suspend.
@@ -284,9 +336,12 @@ static inline void *alloc_image_page(gfp_t gfp_mask, int safe_needed)
         if (safe_needed)
                 do {
                         res = (void *)get_zeroed_page(gfp_mask);
-                        if (res && PageNosaveFree(virt_to_page(res)))
+                        if (res && PageNosaveFree(virt_to_page(res))) {
                                 /* This is for swsusp_free() */
                                 SetPageNosave(virt_to_page(res));
+                                ((struct eaten_page *)res)->next = eaten_pages;
+                                eaten_pages = res;
+                        }
                 } while (res && PageNosaveFree(virt_to_page(res)));
         else
                 res = (void *)get_zeroed_page(gfp_mask);
diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c
index b09bd7c0998d..f77f9397a364 100644
--- a/kernel/power/swsusp.c
+++ b/kernel/power/swsusp.c
@@ -70,11 +70,13 @@
 #include "power.h"
 
 #ifdef CONFIG_HIGHMEM
+unsigned int count_highmem_pages(void);
 int save_highmem(void);
 int restore_highmem(void);
 #else
 static int save_highmem(void) { return 0; }
 static int restore_highmem(void) { return 0; }
+static unsigned int count_highmem_pages(void) { return 0; }
 #endif
 
 extern char resume_file[];
@@ -611,6 +613,52 @@ int swsusp_write(struct pbe *pblist, unsigned int nr_pages)
         return error;
 }
 
+/**
+ *      swsusp_shrink_memory -  Try to free as much memory as needed
+ *
+ *      ... but do not OOM-kill anyone
+ *
+ *      Notice: all userland should be stopped before it is called, or
+ *      livelock is possible.
+ */
+
+#define SHRINK_BITE     10000
+
+int swsusp_shrink_memory(void)
+{
+        long tmp;
+        struct zone *zone;
+        unsigned long pages = 0;
+        unsigned int i = 0;
+        char *p = "-\\|/";
+
+        printk("Shrinking memory...  ");
+        do {
+#ifdef FAST_FREE
+                tmp = 2 * count_highmem_pages();
+                tmp += tmp / 50 + count_data_pages();
+                tmp += (tmp + PBES_PER_PAGE - 1) / PBES_PER_PAGE +
+                        PAGES_FOR_IO;
+                for_each_zone (zone)
+                        if (!is_highmem(zone))
+                                tmp -= zone->free_pages;
+                if (tmp > 0) {
+                        tmp = shrink_all_memory(SHRINK_BITE);
+                        if (!tmp)
+                                return -ENOMEM;
+                        pages += tmp;
+                }
+#else
+                tmp = shrink_all_memory(SHRINK_BITE);
+                pages += tmp;
+#endif
+                printk("\b%c", p[i++%4]);
+        } while (tmp > 0);
+        printk("\bdone (%lu pages freed)\n", pages);
+
+        return 0;
+}
+
 int swsusp_suspend(void)
 {
         int error;
@@ -1030,8 +1078,10 @@ static int read_suspend_image(struct pbe **pblist_ptr)
                 /* Allocate memory for the image and read the data from swap */
                 if (!error)
                         error = alloc_data_pages(pblist, GFP_ATOMIC, 1);
-                if (!error)
+                if (!error) {
+                        release_eaten_pages();
                         error = load_image_data(pblist, &handle, nr_pages);
+                }
                 if (!error)
                         *pblist_ptr = pblist;
         }