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-rw-r--r--kernel/power/swsusp.c569
1 files changed, 45 insertions, 524 deletions
diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c
index 2d5c456..12db1d2 100644
--- a/kernel/power/swsusp.c
+++ b/kernel/power/swsusp.c
@@ -1,11 +1,10 @@
/*
* 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) 1998,2001-2004 Pavel Machek <pavel@suse.cz>
+ * Copyright (C) 1998,2001-2005 Pavel Machek <pavel@suse.cz>
*
* This file is released under the GPLv2.
*
@@ -47,11 +46,7 @@
#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>
@@ -63,10 +58,8 @@
#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>
@@ -84,16 +77,10 @@
#define MAXKEY 32
#define MAXIV 32
-/* References to section boundaries */
-extern const void __nosave_begin, __nosave_end;
-
-/* Variables to be preserved over suspend */
-static int nr_copy_pages_check;
-
extern char resume_file[];
/* Local variables that should not be affected by save */
-static unsigned int nr_copy_pages __nosavedata = 0;
+unsigned int nr_copy_pages __nosavedata = 0;
/* Suspend pagedir is allocated before final copy, therefore it
must be freed after resume
@@ -109,7 +96,7 @@ static unsigned int nr_copy_pages __nosavedata = 0;
MMU hardware.
*/
suspend_pagedir_t *pagedir_nosave __nosavedata = NULL;
-static suspend_pagedir_t *pagedir_save;
+suspend_pagedir_t *pagedir_save;
#define SWSUSP_SIG "S1SUSPEND"
@@ -124,12 +111,6 @@ static struct swsusp_header {
static struct swsusp_info swsusp_info;
/*
- * 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
-
-/*
* Saving part...
*/
@@ -552,346 +533,6 @@ static int write_suspend_image(void)
goto Done;
}
-
-#ifdef CONFIG_HIGHMEM
-struct highmem_page {
- char *data;
- struct page *page;
- struct highmem_page *next;
-};
-
-static struct highmem_page *highmem_copy;
-
-static int save_highmem_zone(struct zone *zone)
-{
- unsigned long zone_pfn;
- mark_free_pages(zone);
- for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) {
- struct page *page;
- struct highmem_page *save;
- void *kaddr;
- unsigned long pfn = zone_pfn + zone->zone_start_pfn;
-
- if (!(pfn%1000))
- printk(".");
- if (!pfn_valid(pfn))
- continue;
- page = pfn_to_page(pfn);
- /*
- * This condition results from rvmalloc() sans vmalloc_32()
- * and architectural memory reservations. This should be
- * corrected eventually when the cases giving rise to this
- * are better understood.
- */
- if (PageReserved(page)) {
- printk("highmem reserved page?!\n");
- continue;
- }
- BUG_ON(PageNosave(page));
- if (PageNosaveFree(page))
- continue;
- save = kmalloc(sizeof(struct highmem_page), GFP_ATOMIC);
- if (!save)
- return -ENOMEM;
- save->next = highmem_copy;
- save->page = page;
- save->data = (void *) get_zeroed_page(GFP_ATOMIC);
- if (!save->data) {
- kfree(save);
- return -ENOMEM;
- }
- kaddr = kmap_atomic(page, KM_USER0);
- memcpy(save->data, kaddr, PAGE_SIZE);
- kunmap_atomic(kaddr, KM_USER0);
- highmem_copy = save;
- }
- return 0;
-}
-#endif /* CONFIG_HIGHMEM */
-
-
-static int save_highmem(void)
-{
-#ifdef CONFIG_HIGHMEM
- struct zone *zone;
- int res = 0;
-
- pr_debug("swsusp: Saving Highmem\n");
- for_each_zone (zone) {
- if (is_highmem(zone))
- res = save_highmem_zone(zone);
- if (res)
- return res;
- }
-#endif
- return 0;
-}
-
-static int restore_highmem(void)
-{
-#ifdef CONFIG_HIGHMEM
- printk("swsusp: Restoring Highmem\n");
- while (highmem_copy) {
- struct highmem_page *save = highmem_copy;
- void *kaddr;
- highmem_copy = save->next;
-
- kaddr = kmap_atomic(save->page, KM_USER0);
- memcpy(kaddr, save->data, PAGE_SIZE);
- kunmap_atomic(kaddr, KM_USER0);
- free_page((long) save->data);
- kfree(save);
- }
-#endif
- return 0;
-}
-
-
-static int pfn_is_nosave(unsigned long pfn)
-{
- unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT;
- unsigned long nosave_end_pfn = PAGE_ALIGN(__pa(&__nosave_end)) >> PAGE_SHIFT;
- return (pfn >= nosave_begin_pfn) && (pfn < nosave_end_pfn);
-}
-
-/**
- * saveable - Determine whether a page should be cloned or not.
- * @pfn: The page
- *
- * We save a page if it's Reserved, and not in the range of pages
- * statically defined as 'unsaveable', or if it isn't reserved, and
- * isn't part of a free chunk of pages.
- */
-
-static int saveable(struct zone * zone, unsigned long * zone_pfn)
-{
- unsigned long pfn = *zone_pfn + zone->zone_start_pfn;
- struct page * page;
-
- if (!pfn_valid(pfn))
- return 0;
-
- page = pfn_to_page(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);
- return 0;
- }
- if (PageNosaveFree(page))
- return 0;
-
- return 1;
-}
-
-static void count_data_pages(void)
-{
- struct zone *zone;
- unsigned long zone_pfn;
-
- nr_copy_pages = 0;
-
- for_each_zone (zone) {
- if (is_highmem(zone))
- continue;
- mark_free_pages(zone);
- for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
- nr_copy_pages += saveable(zone, &zone_pfn);
- }
-}
-
-
-static void copy_data_pages(void)
-{
- struct zone *zone;
- unsigned long zone_pfn;
- struct pbe * pbe = pagedir_nosave;
-
- pr_debug("copy_data_pages(): pages to copy: %d\n", nr_copy_pages);
- for_each_zone (zone) {
- if (is_highmem(zone))
- continue;
- mark_free_pages(zone);
- for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) {
- if (saveable(zone, &zone_pfn)) {
- struct page * page;
- page = pfn_to_page(zone_pfn + zone->zone_start_pfn);
- BUG_ON(!pbe);
- pbe->orig_address = (long) page_address(page);
- /* copy_page is not usable for copying task structs. */
- memcpy((void *)pbe->address, (void *)pbe->orig_address, PAGE_SIZE);
- pbe = pbe->next;
- }
- }
- }
- BUG_ON(pbe);
-}
-
-
-/**
- * calc_nr - Determine the number of pages needed for a pbe list.
- */
-
-static int calc_nr(int nr_copy)
-{
- return nr_copy + (nr_copy+PBES_PER_PAGE-2)/(PBES_PER_PAGE-1);
-}
-
-/**
- * free_pagedir - free pages allocated with alloc_pagedir()
- */
-
-static inline void free_pagedir(struct pbe *pblist)
-{
- struct pbe *pbe;
-
- while (pblist) {
- pbe = (pblist + PB_PAGE_SKIP)->next;
- free_page((unsigned long)pblist);
- pblist = pbe;
- }
-}
-
-/**
- * fill_pb_page - Create a list of PBEs on a given memory page
- */
-
-static inline void fill_pb_page(struct pbe *pbpage)
-{
- struct pbe *p;
-
- p = pbpage;
- pbpage += PB_PAGE_SKIP;
- do
- p->next = p + 1;
- while (++p < pbpage);
-}
-
-/**
- * create_pbe_list - Create a list of PBEs on top of a given chain
- * of memory pages allocated with alloc_pagedir()
- */
-
-static void create_pbe_list(struct pbe *pblist, unsigned nr_pages)
-{
- struct pbe *pbpage, *p;
- unsigned num = PBES_PER_PAGE;
-
- for_each_pb_page (pbpage, pblist) {
- if (num >= nr_pages)
- break;
-
- fill_pb_page(pbpage);
- num += PBES_PER_PAGE;
- }
- if (pbpage) {
- for (num -= PBES_PER_PAGE - 1, p = pbpage; num < nr_pages; p++, num++)
- p->next = p + 1;
- p->next = NULL;
- }
- pr_debug("create_pbe_list(): initialized %d PBEs\n", num);
-}
-
-/**
- * alloc_pagedir - Allocate the page directory.
- *
- * First, determine exactly how many pages we need and
- * allocate them.
- *
- * We arrange the pages in a chain: each page is an array of PBES_PER_PAGE
- * struct pbe elements (pbes) and the last element in the page points
- * to the next page.
- *
- * On each page we set up a list of struct_pbe elements.
- */
-
-static struct pbe * alloc_pagedir(unsigned nr_pages)
-{
- unsigned num;
- struct pbe *pblist, *pbe;
-
- if (!nr_pages)
- return NULL;
-
- pr_debug("alloc_pagedir(): nr_pages = %d\n", nr_pages);
- pblist = (struct pbe *)get_zeroed_page(GFP_ATOMIC | __GFP_COLD);
- for (pbe = pblist, num = PBES_PER_PAGE; pbe && num < nr_pages;
- pbe = pbe->next, num += PBES_PER_PAGE) {
- pbe += PB_PAGE_SKIP;
- pbe->next = (struct pbe *)get_zeroed_page(GFP_ATOMIC | __GFP_COLD);
- }
- if (!pbe) { /* get_zeroed_page() failed */
- free_pagedir(pblist);
- pblist = NULL;
- }
- return pblist;
-}
-
-/**
- * free_image_pages - Free pages allocated for snapshot
- */
-
-static void free_image_pages(void)
-{
- struct pbe * p;
-
- for_each_pbe (p, pagedir_save) {
- if (p->address) {
- ClearPageNosave(virt_to_page(p->address));
- free_page(p->address);
- p->address = 0;
- }
- }
-}
-
-/**
- * alloc_image_pages - Allocate pages for the snapshot.
- */
-
-static int alloc_image_pages(void)
-{
- struct pbe * p;
-
- for_each_pbe (p, pagedir_save) {
- p->address = get_zeroed_page(GFP_ATOMIC | __GFP_COLD);
- if (!p->address)
- return -ENOMEM;
- SetPageNosave(virt_to_page(p->address));
- }
- return 0;
-}
-
-/* Free pages we allocated for suspend. Suspend pages are alocated
- * before atomic copy, so we need to free them after resume.
- */
-void swsusp_free(void)
-{
- BUG_ON(PageNosave(virt_to_page(pagedir_save)));
- BUG_ON(PageNosaveFree(virt_to_page(pagedir_save)));
- free_image_pages();
- free_pagedir(pagedir_save);
-}
-
-
-/**
- * enough_free_mem - Make sure we enough free memory to snapshot.
- *
- * Returns TRUE or FALSE after checking the number of available
- * free pages.
- */
-
-static int enough_free_mem(void)
-{
- if (nr_free_pages() < (nr_copy_pages + PAGES_FOR_IO)) {
- pr_debug("swsusp: Not enough free pages: Have %d\n",
- nr_free_pages());
- return 0;
- }
- return 1;
-}
-
-
/**
* enough_swap - Make sure we have enough swap to save the image.
*
@@ -902,87 +543,14 @@ static int enough_free_mem(void)
* We should only consider resume_device.
*/
-static int enough_swap(void)
+int enough_swap(unsigned nr_pages)
{
struct sysinfo i;
si_swapinfo(&i);
- if (i.freeswap < (nr_copy_pages + PAGES_FOR_IO)) {
- pr_debug("swsusp: Not enough swap. Need %ld\n",i.freeswap);
- return 0;
- }
- return 1;
-}
-
-static int swsusp_alloc(void)
-{
- int error;
-
- pagedir_nosave = NULL;
- nr_copy_pages = calc_nr(nr_copy_pages);
- nr_copy_pages_check = nr_copy_pages;
-
- pr_debug("suspend: (pages needed: %d + %d free: %d)\n",
- nr_copy_pages, PAGES_FOR_IO, nr_free_pages());
-
- if (!enough_free_mem())
- return -ENOMEM;
-
- if (!enough_swap())
- return -ENOSPC;
-
- if (MAX_PBES < nr_copy_pages / PBES_PER_PAGE +
- !!(nr_copy_pages % PBES_PER_PAGE))
- return -ENOSPC;
-
- if (!(pagedir_save = alloc_pagedir(nr_copy_pages))) {
- printk(KERN_ERR "suspend: Allocating pagedir failed.\n");
- return -ENOMEM;
- }
- create_pbe_list(pagedir_save, nr_copy_pages);
- pagedir_nosave = pagedir_save;
- if ((error = alloc_image_pages())) {
- printk(KERN_ERR "suspend: Allocating image pages failed.\n");
- swsusp_free();
- return error;
- }
-
- return 0;
-}
-
-static int suspend_prepare_image(void)
-{
- int error;
-
- pr_debug("swsusp: critical section: \n");
- if (save_highmem()) {
- printk(KERN_CRIT "Suspend machine: Not enough free pages for highmem\n");
- restore_highmem();
- return -ENOMEM;
- }
-
- drain_local_pages();
- count_data_pages();
- printk("swsusp: Need to copy %u pages\n", nr_copy_pages);
-
- error = swsusp_alloc();
- if (error)
- return error;
-
- /* During allocating of suspend pagedir, new cold pages may appear.
- * Kill them.
- */
- drain_local_pages();
- copy_data_pages();
-
- /*
- * End of critical section. From now on, we can write to memory,
- * but we should not touch disk. This specially means we must _not_
- * touch swap space! Except we must write out our image of course.
- */
-
- printk("swsusp: critical section/: done (%d pages copied)\n", nr_copy_pages );
- return 0;
+ pr_debug("swsusp: available swap: %lu pages\n", i.freeswap);
+ return i.freeswap > (nr_pages + PAGES_FOR_IO +
+ (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE);
}
@@ -994,7 +562,7 @@ static int suspend_prepare_image(void)
int swsusp_write(void)
{
int error;
- device_resume();
+
lock_swapdevices();
error = write_suspend_image();
/* This will unlock ignored swap devices since writing is finished */
@@ -1004,14 +572,6 @@ int swsusp_write(void)
}
-extern asmlinkage int swsusp_arch_suspend(void);
-extern asmlinkage int swsusp_arch_resume(void);
-
-
-asmlinkage int swsusp_save(void)
-{
- return suspend_prepare_image();
-}
int swsusp_suspend(void)
{
@@ -1043,7 +603,6 @@ int swsusp_suspend(void)
printk(KERN_ERR "Error %d suspending\n", error);
/* Restore control flow magically appears here */
restore_processor_state();
- BUG_ON (nr_copy_pages_check != nr_copy_pages);
restore_highmem();
device_power_up();
local_irq_enable();
@@ -1063,6 +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();
@@ -1078,54 +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(unsigned 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
@@ -1143,7 +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;
}
@@ -1162,7 +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;
@@ -1170,41 +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;
@@ -1214,15 +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;
}
@@ -1440,9 +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;
@@ -1485,15 +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;
}
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