]> err.no Git - linux-2.6/blobdiff - kernel/power/swsusp.c
Merge master.kernel.org:/pub/scm/linux/kernel/git/airlied/drm-2.6
[linux-2.6] / kernel / power / swsusp.c
index f6abfdb0a02a940faac62cbcb641902b76aa0458..12db1d2ad61f89e5667f21f339b2bd9c3fd3969f 100644 (file)
@@ -1,8 +1,7 @@
 /*
  * linux/kernel/power/swsusp.c
  *
- * This file is to realize architecture-independent
- * machine suspend feature using pretty near only high-level routines
+ * This file provides code to write suspend image to swap and read it back.
  *
  * Copyright (C) 1998-2001 Gabor Kuti <seasons@fornax.hu>
  * Copyright (C) 1998,2001-2005 Pavel Machek <pavel@suse.cz>
 #include <linux/utsname.h>
 #include <linux/version.h>
 #include <linux/delay.h>
-#include <linux/reboot.h>
 #include <linux/bitops.h>
-#include <linux/vt_kern.h>
-#include <linux/kbd_kern.h>
-#include <linux/keyboard.h>
 #include <linux/spinlock.h>
 #include <linux/genhd.h>
 #include <linux/kernel.h>
 #include <linux/swapops.h>
 #include <linux/bootmem.h>
 #include <linux/syscalls.h>
-#include <linux/console.h>
 #include <linux/highmem.h>
 #include <linux/bio.h>
-#include <linux/mount.h>
 
 #include <asm/uaccess.h>
 #include <asm/mmu_context.h>
@@ -569,7 +562,7 @@ int enough_swap(unsigned nr_pages)
 int swsusp_write(void)
 {
        int error;
-       device_resume();
+
        lock_swapdevices();
        error = write_suspend_image();
        /* This will unlock ignored swap devices since writing is finished */
@@ -629,6 +622,11 @@ int swsusp_resume(void)
         * execution continues at place where swsusp_arch_suspend was called
          */
        BUG_ON(!error);
+       /* The only reason why swsusp_arch_resume() can fail is memory being
+        * very tight, so we have to free it as soon as we can to avoid
+        * subsequent failures
+        */
+       swsusp_free();
        restore_processor_state();
        restore_highmem();
        touch_softlockup_watchdog();
@@ -644,54 +642,28 @@ int swsusp_resume(void)
  *
  *     We don't know which pages are usable until we allocate them.
  *
- *     Allocated but unusable (ie eaten) memory pages are linked together
- *     to create a list, so that we can free them easily
- *
- *     We could have used a type other than (void *)
- *     for this purpose, but ...
+ *     Allocated but unusable (ie eaten) memory pages are marked so that
+ *     swsusp_free() can release them
  */
-static void **eaten_memory = NULL;
-
-static inline void eat_page(void *page)
-{
-       void **c;
-
-       c = eaten_memory;
-       eaten_memory = page;
-       *eaten_memory = c;
-}
 
-unsigned long get_usable_page(gfp_t gfp_mask)
+unsigned long get_safe_page(gfp_t gfp_mask)
 {
        unsigned long m;
 
-       m = get_zeroed_page(gfp_mask);
-       while (!PageNosaveFree(virt_to_page(m))) {
-               eat_page((void *)m);
+       do {
                m = get_zeroed_page(gfp_mask);
-               if (!m)
-                       break;
+               if (m && PageNosaveFree(virt_to_page(m)))
+                       /* This is for swsusp_free() */
+                       SetPageNosave(virt_to_page(m));
+       } while (m && PageNosaveFree(virt_to_page(m)));
+       if (m) {
+               /* This is for swsusp_free() */
+               SetPageNosave(virt_to_page(m));
+               SetPageNosaveFree(virt_to_page(m));
        }
        return m;
 }
 
-void free_eaten_memory(void)
-{
-       unsigned long m;
-       void **c;
-       int i = 0;
-
-       c = eaten_memory;
-       while (c) {
-               m = (unsigned long)c;
-               c = *c;
-               free_page(m);
-               i++;
-       }
-       eaten_memory = NULL;
-       pr_debug("swsusp: %d unused pages freed\n", i);
-}
-
 /**
  *     check_pagedir - We ensure here that pages that the PBEs point to
  *     won't collide with pages where we're going to restore from the loaded
@@ -709,7 +681,7 @@ static int check_pagedir(struct pbe *pblist)
                p->address = 0UL;
 
        for_each_pbe (p, pblist) {
-               p->address = get_usable_page(GFP_ATOMIC);
+               p->address = get_safe_page(GFP_ATOMIC);
                if (!p->address)
                        return -ENOMEM;
        }
@@ -728,7 +700,7 @@ static struct pbe * swsusp_pagedir_relocate(struct pbe *pblist)
        unsigned long zone_pfn;
        struct pbe *pbpage, *tail, *p;
        void *m;
-       int rel = 0, error = 0;
+       int rel = 0;
 
        if (!pblist) /* a sanity check */
                return NULL;
@@ -736,41 +708,37 @@ static struct pbe * swsusp_pagedir_relocate(struct pbe *pblist)
        pr_debug("swsusp: Relocating pagedir (%lu pages to check)\n",
                        swsusp_info.pagedir_pages);
 
-       /* Set page flags */
+       /* Clear page flags */
 
        for_each_zone (zone) {
                for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
-                       SetPageNosaveFree(pfn_to_page(zone_pfn +
+                       if (pfn_valid(zone_pfn + zone->zone_start_pfn))
+                               ClearPageNosaveFree(pfn_to_page(zone_pfn +
                                        zone->zone_start_pfn));
        }
 
-       /* Clear orig addresses */
+       /* Mark orig addresses */
 
        for_each_pbe (p, pblist)
-               ClearPageNosaveFree(virt_to_page(p->orig_address));
+               SetPageNosaveFree(virt_to_page(p->orig_address));
 
        tail = pblist + PB_PAGE_SKIP;
 
        /* Relocate colliding pages */
 
        for_each_pb_page (pbpage, pblist) {
-               if (!PageNosaveFree(virt_to_page((unsigned long)pbpage))) {
-                       m = (void *)get_usable_page(GFP_ATOMIC | __GFP_COLD);
-                       if (!m) {
-                               error = -ENOMEM;
-                               break;
-                       }
+               if (PageNosaveFree(virt_to_page((unsigned long)pbpage))) {
+                       m = (void *)get_safe_page(GFP_ATOMIC | __GFP_COLD);
+                       if (!m)
+                               return NULL;
                        memcpy(m, (void *)pbpage, PAGE_SIZE);
                        if (pbpage == pblist)
                                pblist = (struct pbe *)m;
                        else
                                tail->next = (struct pbe *)m;
-
-                       eat_page((void *)pbpage);
                        pbpage = (struct pbe *)m;
 
                        /* We have to link the PBEs again */
-
                        for (p = pbpage; p < pbpage + PB_PAGE_SKIP; p++)
                                if (p->next) /* needed to save the end */
                                        p->next = p + 1;
@@ -780,15 +748,13 @@ static struct pbe * swsusp_pagedir_relocate(struct pbe *pblist)
                tail = pbpage + PB_PAGE_SKIP;
        }
 
-       if (error) {
-               printk("\nswsusp: Out of memory\n\n");
-               free_pagedir(pblist);
-               free_eaten_memory();
-               pblist = NULL;
-               /* Is this even worth handling? It should never ever happen, and we
-                  have just lost user's state, anyway... */
-       } else
-               printk("swsusp: Relocated %d pages\n", rel);
+       /* This is for swsusp_free() */
+       for_each_pb_page (pbpage, pblist) {
+               SetPageNosave(virt_to_page(pbpage));
+               SetPageNosaveFree(virt_to_page(pbpage));
+       }
+
+       printk("swsusp: Relocated %d pages\n", rel);
 
        return pblist;
 }
@@ -1006,9 +972,7 @@ static int read_pagedir(struct pbe *pblist)
                        break;
        }
 
-       if (error)
-               free_pagedir(pblist);
-       else
+       if (!error)
                BUG_ON(i != swsusp_info.pagedir_pages);
 
        return error;
@@ -1051,15 +1015,6 @@ static int read_suspend_image(void)
        if (!error)
                error = data_read(pagedir_nosave);
 
-       if (error) { /* We fail cleanly */
-               free_eaten_memory();
-               for_each_pbe (p, pagedir_nosave)
-                       if (p->address) {
-                               free_page(p->address);
-                               p->address = 0UL;
-                       }
-               free_pagedir(pagedir_nosave);
-       }
        return error;
 }