/*
* 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) 1998,2001-200
4 Pavel Machek <pavel@suse.cz>
+ * Copyright (C) 1998,2001-200
5 Pavel Machek <pavel@suse.cz>
*
* This file is released under the GPLv2.
*
* I'd like to thank the following people for their work:
- *
+ *
* Pavel Machek <pavel@ucw.cz>:
* Modifications, defectiveness pointing, being with me at the very beginning,
* suspend to swap space, stop all tasks. Port to 2.4.18-ac and 2.5.17.
*
- * Steve Doddi <dirk@loth.demon.co.uk>:
+ * Steve Doddi <dirk@loth.demon.co.uk>:
* Support the possibility of hardware state restoring.
*
* Raph <grey.havens@earthling.net>:
* Alex Badea <vampire@go.ro>:
* Fixed runaway init
*
+ * Rafael J. Wysocki <rjw@sisk.pl>
+ * Reworked the freeing of memory and the handling of swap
+ *
* More state savers are welcome. Especially for the scsi layer...
*
* For TODOs,FIXMEs also look in Documentation/power/swsusp.txt
*/
-#include <linux/module.h>
#include <linux/mm.h>
#include <linux/suspend.h>
-#include <linux/smp_lock.h>
-#include <linux/file.h>
-#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/major.h>
#include <linux/swap.h>
#include <linux/pm.h>
-#include <linux/device.h>
-#include <linux/buffer_head.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 <asm/uaccess.h>
-#include <asm/mmu_context.h>
-#include <asm/pgtable.h>
-#include <asm/tlbflush.h>
-#include <asm/io.h>
#include "power.h"
-/* 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 */
-unsigned int nr_copy_pages __nosavedata = 0;
-
-/* Suspend pagedir is allocated before final copy, therefore it
- must be freed after resume
-
- Warning: this is evil. There are actually two pagedirs at time of
- resume. One is "pagedir_save", which is empty frame allocated at
- time of suspend, that must be freed. Second is "pagedir_nosave",
- allocated at time of resume, that travels through memory not to
- collide with anything.
-
- Warning: this is even more evil than it seems. Pagedirs this file
- talks about are completely different from page directories used by
- MMU hardware.
- */
-suspend_pagedir_t *pagedir_nosave __nosavedata = NULL;
-static suspend_pagedir_t *pagedir_save;
-
-#define SWSUSP_SIG "S1SUSPEND"
-
-static struct swsusp_header {
- char reserved[PAGE_SIZE - 20 - sizeof(swp_entry_t)];
- swp_entry_t swsusp_info;
- char orig_sig[10];
- char sig[10];
-} __attribute__((packed, aligned(PAGE_SIZE))) 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...
- */
-
-/* We memorize in swapfile_used what swap devices are used for suspension */
-#define SWAPFILE_UNUSED 0
-#define SWAPFILE_SUSPEND 1 /* This is the suspending device */
-#define SWAPFILE_IGNORED 2 /* Those are other swap devices ignored for suspension */
-
-static unsigned short swapfile_used[MAX_SWAPFILES];
-static unsigned short root_swap;
-
-static int mark_swapfiles(swp_entry_t prev)
-{
- int error;
-
- rw_swap_page_sync(READ,
- swp_entry(root_swap, 0),
- virt_to_page((unsigned long)&swsusp_header));
- if (!memcmp("SWAP-SPACE",swsusp_header.sig, 10) ||
- !memcmp("SWAPSPACE2",swsusp_header.sig, 10)) {
- memcpy(swsusp_header.orig_sig,swsusp_header.sig, 10);
- memcpy(swsusp_header.sig,SWSUSP_SIG, 10);
- swsusp_header.swsusp_info = prev;
- error = rw_swap_page_sync(WRITE,
- swp_entry(root_swap, 0),
- virt_to_page((unsigned long)
- &swsusp_header));
- } else {
- pr_debug("swsusp: Partition is not swap space.\n");
- error = -ENODEV;
- }
- return error;
-}
-
-/*
- * Check whether the swap device is the specified resume
- * device, irrespective of whether they are specified by
- * identical names.
- *
- * (Thus, device inode aliasing is allowed. You can say /dev/hda4
- * instead of /dev/ide/host0/bus0/target0/lun0/part4 [if using devfs]
- * and they'll be considered the same device. This is *necessary* for
- * devfs, since the resume code can only recognize the form /dev/hda4,
- * but the suspend code would see the long name.)
- */
-static int is_resume_device(const struct swap_info_struct *swap_info)
-{
- struct file *file = swap_info->swap_file;
- struct inode *inode = file->f_dentry->d_inode;
-
- return S_ISBLK(inode->i_mode) &&
- swsusp_resume_device == MKDEV(imajor(inode), iminor(inode));
-}
-
-static int swsusp_swap_check(void) /* This is called before saving image */
-{
- int i, len;
-
- len=strlen(resume_file);
- root_swap = 0xFFFF;
-
- swap_list_lock();
- for(i=0; i<MAX_SWAPFILES; i++) {
- if (swap_info[i].flags == 0) {
- swapfile_used[i]=SWAPFILE_UNUSED;
- } else {
- if(!len) {
- printk(KERN_WARNING "resume= option should be used to set suspend device" );
- if(root_swap == 0xFFFF) {
- swapfile_used[i] = SWAPFILE_SUSPEND;
- root_swap = i;
- } else
- swapfile_used[i] = SWAPFILE_IGNORED;
- } else {
- /* we ignore all swap devices that are not the resume_file */
- if (is_resume_device(&swap_info[i])) {
- swapfile_used[i] = SWAPFILE_SUSPEND;
- root_swap = i;
- } else {
- swapfile_used[i] = SWAPFILE_IGNORED;
- }
- }
- }
- }
- swap_list_unlock();
- return (root_swap != 0xffff) ? 0 : -ENODEV;
-}
-
-/**
- * This is called after saving image so modification
- * will be lost after resume... and that's what we want.
- * we make the device unusable. A new call to
- * lock_swapdevices can unlock the devices.
- */
-static void lock_swapdevices(void)
-{
- int i;
-
- swap_list_lock();
- for(i = 0; i< MAX_SWAPFILES; i++)
- if(swapfile_used[i] == SWAPFILE_IGNORED) {
- swap_info[i].flags ^= 0xFF;
- }
- swap_list_unlock();
-}
-
-/**
- * write_swap_page - Write one page to a fresh swap location.
- * @addr: Address we're writing.
- * @loc: Place to store the entry we used.
- *
- * Allocate a new swap entry and 'sync' it. Note we discard -EIO
- * errors. That is an artifact left over from swsusp. It did not
- * check the return of rw_swap_page_sync() at all, since most pages
- * written back to swap would return -EIO.
- * This is a partial improvement, since we will at least return other
- * errors, though we need to eventually fix the damn code.
- */
-static int write_page(unsigned long addr, swp_entry_t * loc)
-{
- swp_entry_t entry;
- int error = 0;
-
- entry = get_swap_page();
- if (swp_offset(entry) &&
- swapfile_used[swp_type(entry)] == SWAPFILE_SUSPEND) {
- error = rw_swap_page_sync(WRITE, entry,
- virt_to_page(addr));
- if (error == -EIO)
- error = 0;
- if (!error)
- *loc = entry;
- } else
- error = -ENOSPC;
- return error;
-}
-
-/**
- * data_free - Free the swap entries used by the saved image.
- *
- * Walk the list of used swap entries and free each one.
- * This is only used for cleanup when suspend fails.
- */
-static void data_free(void)
-{
- swp_entry_t entry;
- int i;
-
- for (i = 0; i < nr_copy_pages; i++) {
- entry = (pagedir_nosave + i)->swap_address;
- if (entry.val)
- swap_free(entry);
- else
- break;
- (pagedir_nosave + i)->swap_address = (swp_entry_t){0};
- }
-}
-
-/**
- * data_write - Write saved image to swap.
- *
- * Walk the list of pages in the image and sync each one to swap.
+ * Preferred image size in bytes (tunable via /sys/power/image_size).
+ * When it is set to N, swsusp will do its best to ensure the image
+ * size will not exceed N bytes, but if that is impossible, it will
+ * try to create the smallest image possible.
*/
-static int data_write(void)
-{
- int error = 0, i = 0;
- unsigned int mod = nr_copy_pages / 100;
- struct pbe *p;
-
- if (!mod)
- mod = 1;
-
- printk( "Writing data to swap (%d pages)... ", nr_copy_pages );
- for_each_pbe(p, pagedir_nosave) {
- if (!(i%mod))
- printk( "\b\b\b\b%3d%%", i / mod );
- if ((error = write_page(p->address, &(p->swap_address))))
- return error;
- i++;
- }
- printk("\b\b\b\bdone\n");
- return error;
-}
-
-static void dump_info(void)
-{
- pr_debug(" swsusp: Version: %u\n",swsusp_info.version_code);
- pr_debug(" swsusp: Num Pages: %ld\n",swsusp_info.num_physpages);
- pr_debug(" swsusp: UTS Sys: %s\n",swsusp_info.uts.sysname);
- pr_debug(" swsusp: UTS Node: %s\n",swsusp_info.uts.nodename);
- pr_debug(" swsusp: UTS Release: %s\n",swsusp_info.uts.release);
- pr_debug(" swsusp: UTS Version: %s\n",swsusp_info.uts.version);
- pr_debug(" swsusp: UTS Machine: %s\n",swsusp_info.uts.machine);
- pr_debug(" swsusp: UTS Domain: %s\n",swsusp_info.uts.domainname);
- pr_debug(" swsusp: CPUs: %d\n",swsusp_info.cpus);
- pr_debug(" swsusp: Image: %ld Pages\n",swsusp_info.image_pages);
- pr_debug(" swsusp: Pagedir: %ld Pages\n",swsusp_info.pagedir_pages);
-}
-
-static void init_header(void)
-{
- memset(&swsusp_info, 0, sizeof(swsusp_info));
- swsusp_info.version_code = LINUX_VERSION_CODE;
- swsusp_info.num_physpages = num_physpages;
- memcpy(&swsusp_info.uts, &system_utsname, sizeof(system_utsname));
-
- swsusp_info.suspend_pagedir = pagedir_nosave;
- swsusp_info.cpus = num_online_cpus();
- swsusp_info.image_pages = nr_copy_pages;
-}
-
-static int close_swap(void)
-{
- swp_entry_t entry;
- int error;
-
- dump_info();
- error = write_page((unsigned long)&swsusp_info, &entry);
- if (!error) {
- printk( "S" );
- error = mark_swapfiles(entry);
- printk( "|\n" );
- }
- return error;
-}
-
-/**
- * free_pagedir_entries - Free pages used by the page directory.
- *
- * This is used during suspend for error recovery.
- */
-
-static void free_pagedir_entries(void)
-{
- int i;
-
- for (i = 0; i < swsusp_info.pagedir_pages; i++)
- swap_free(swsusp_info.pagedir[i]);
-}
-
-
-/**
- * write_pagedir - Write the array of pages holding the page directory.
- * @last: Last swap entry we write (needed for header).
- */
-
-static int write_pagedir(void)
-{
- int error = 0;
- unsigned n = 0;
- struct pbe * pbe;
-
- printk( "Writing pagedir...");
- for_each_pb_page(pbe, pagedir_nosave) {
- if ((error = write_page((unsigned long)pbe, &swsusp_info.pagedir[n++])))
- return error;
- }
-
- swsusp_info.pagedir_pages = n;
- printk("done (%u pages)\n", n);
- return error;
-}
-
-/**
- * write_suspend_image - Write entire image and metadata.
- *
- */
-
-static int write_suspend_image(void)
-{
- int error;
-
- init_header();
- if ((error = data_write()))
- goto FreeData;
-
- if ((error = write_pagedir()))
- goto FreePagedir;
-
- if ((error = close_swap()))
- goto FreePagedir;
- Done:
- return error;
- FreePagedir:
- free_pagedir_entries();
- FreeData:
- data_free();
- goto Done;
-}
+unsigned long image_size = 500 * 1024 * 1024;
+int in_suspend __nosavedata = 0;
#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;
- }
+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
- 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
+ * The following functions are used for tracing the allocated
+ * swap pages, so that they can be freed in case of an error.
*
- * 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.
+ * The functions operate on a linked bitmap structure defined
+ * in power.h
*/
-static int saveable(struct zone * zone, unsigned long * zone_pfn)
+void free_bitmap(struct bitmap_page *bitmap)
{
- unsigned long pfn = *zone_pfn + zone->zone_start_pfn;
- struct page * page;
-
- if (!pfn_valid(pfn))
- return 0;
+ struct bitmap_page *bp;
- 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;
+ while (bitmap) {
+ bp = bitmap->next;
+ free_page((unsigned long)bitmap);
+ bitmap = bp;
}
- if (PageNosaveFree(page))
- return 0;
-
- return 1;
}
-static void count_data_pages(void)
+struct bitmap_page *alloc_bitmap(unsigned int nr_bits)
{
- 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);
- }
-}
+ struct bitmap_page *bitmap, *bp;
+ unsigned int n;
+ if (!nr_bits)
+ return NULL;
-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;
- }
+ bitmap = (struct bitmap_page *)get_zeroed_page(GFP_KERNEL);
+ bp = bitmap;
+ for (n = BITMAP_PAGE_BITS; n < nr_bits; n += BITMAP_PAGE_BITS) {
+ bp->next = (struct bitmap_page *)get_zeroed_page(GFP_KERNEL);
+ bp = bp->next;
+ if (!bp) {
+ free_bitmap(bitmap);
+ return NULL;
}
}
- BUG_ON(pbe);
-}
-
-
-/**
- * calc_nr - Determine the number of pages needed for a pbe list.
- */
-
-static int calc_nr(int nr_copy)
-{
- int extra = 0;
- int mod = !!(nr_copy % PBES_PER_PAGE);
- int diff = (nr_copy / PBES_PER_PAGE) + mod;
-
- do {
- extra += diff;
- nr_copy += diff;
- mod = !!(nr_copy % PBES_PER_PAGE);
- diff = (nr_copy / PBES_PER_PAGE) + mod - extra;
- } while (diff > 0);
-
- return nr_copy;
+ return bitmap;
}
-/**
- * free_pagedir - free pages allocated with alloc_pagedir()
- */
-
-static inline void free_pagedir(struct pbe *pblist)
+static int bitmap_set(struct bitmap_page *bitmap, unsigned long bit)
{
- struct pbe *pbe;
+ unsigned int n;
- while (pblist) {
- pbe = (pblist + PB_PAGE_SKIP)->next;
- free_page((unsigned long)pblist);
- pblist = pbe;
+ n = BITMAP_PAGE_BITS;
+ while (bitmap && n <= bit) {
+ n += BITMAP_PAGE_BITS;
+ bitmap = bitmap->next;
}
+ if (!bitmap)
+ return -EINVAL;
+ n -= BITMAP_PAGE_BITS;
+ bit -= n;
+ n = 0;
+ while (bit >= BITS_PER_CHUNK) {
+ bit -= BITS_PER_CHUNK;
+ n++;
+ }
+ bitmap->chunks[n] |= (1UL << bit);
+ return 0;
}
-/**
- * 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)
+unsigned long alloc_swap_page(int swap, struct bitmap_page *bitmap)
{
- struct pbe * p;
+ unsigned long offset;
- for_each_pbe(p, pagedir_save) {
- if (p->address) {
- ClearPageNosave(virt_to_page(p->address));
- free_page(p->address);
- p->address = 0;
+ offset = swp_offset(get_swap_page_of_type(swap));
+ if (offset) {
+ if (bitmap_set(bitmap, offset)) {
+ swap_free(swp_entry(swap, offset));
+ offset = 0;
}
}
+ return offset;
}
-/**
- * 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;
-}
-
-void swsusp_free(void)
+void free_all_swap_pages(int swap, struct bitmap_page *bitmap)
{
- 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.
- */
+ unsigned int bit, n;
+ unsigned long test;
-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;
+ bit = 0;
+ while (bitmap) {
+ for (n = 0; n < BITMAP_PAGE_CHUNKS; n++)
+ for (test = 1UL; test; test <<= 1) {
+ if (bitmap->chunks[n] & test)
+ swap_free(swp_entry(swap, bit));
+ bit++;
+ }
+ bitmap = bitmap->next;
}
- return 1;
}
-
/**
- * enough_swap - Make sure we have enough swap to save the image.
+ * swsusp_shrink_memory - Try to free as much memory as needed
*
- * Returns TRUE or FALSE after checking the total amount of swap
- * space avaiable.
+ * ... but do not OOM-kill anyone
*
- * FIXME: si_swapinfo(&i) returns all swap devices information.
- * We should only consider resume_device.
+ * Notice: all userland should be stopped before it is called, or
+ * livelock is possible.
*/
-static int enough_swap(void)
-{
- 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;
-
- pr_debug("suspend: (pages needed: %d + %d free: %d)\n",
- nr_copy_pages, PAGES_FOR_IO, nr_free_pages());
+#define SHRINK_BITE 10000
- pagedir_nosave = NULL;
- if (!enough_free_mem())
- return -ENOMEM;
-
- if (!enough_swap())
- return -ENOSPC;
-
- nr_copy_pages = calc_nr(nr_copy_pages);
-
- 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;
- }
-
- nr_copy_pages_check = nr_copy_pages;
- return 0;
-}
-
-static int suspend_prepare_image(void)
+int swsusp_shrink_memory(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();
+ long size, tmp;
+ struct zone *zone;
+ unsigned long pages = 0;
+ unsigned int i = 0;
+ char *p = "-\\|/";
- /*
- * 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("Shrinking memory... ");
+ do {
+ size = 2 * count_highmem_pages();
+ size += size / 50 + count_data_pages();
+ size += (size + PBES_PER_PAGE - 1) / PBES_PER_PAGE +
+ PAGES_FOR_IO;
+ tmp = size;
+ 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 if (size > image_size / PAGE_SIZE) {
+ tmp = shrink_all_memory(SHRINK_BITE);
+ pages += tmp;
+ }
+ printk("\b%c", p[i++%4]);
+ } while (tmp > 0);
+ printk("\bdone (%lu pages freed)\n", pages);
- printk("swsusp: critical section/: done (%d pages copied)\n", nr_copy_pages );
return 0;
}
-
-/* It is important _NOT_ to umount filesystems at this point. We want
- * them synced (in case something goes wrong) but we DO not want to mark
- * filesystem clean: it is not. (And it does not matter, if we resume
- * correctly, we'll mark system clean, anyway.)
- */
-int swsusp_write(void)
-{
- int error;
- device_resume();
- lock_swapdevices();
- error = write_suspend_image();
- /* This will unlock ignored swap devices since writing is finished */
- lock_swapdevices();
- return error;
-
-}
-
-
-extern asmlinkage int swsusp_arch_suspend(void);
-extern asmlinkage int swsusp_arch_resume(void);
-
-
-asmlinkage int swsusp_save(void)
-{
- int error = 0;
-
- if ((error = swsusp_swap_check())) {
- printk(KERN_ERR "swsusp: FATAL: cannot find swap device, try "
- "swapon -a!\n");
- return error;
- }
- return suspend_prepare_image();
-}
-
int swsusp_suspend(void)
{
int error;
+
if ((error = arch_prepare_suspend()))
return error;
local_irq_disable();
*/
if ((error = device_power_down(PMSG_FREEZE))) {
printk(KERN_ERR "Some devices failed to power down, aborting suspend\n");
- local_irq_enable();
- swsusp_free();
- return error;
+ goto Enable_irqs;
+ }
+
+ if ((error = save_highmem())) {
+ printk(KERN_ERR "swsusp: Not enough free pages for highmem\n");
+ goto Restore_highmem;
}
+
save_processor_state();
if ((error = swsusp_arch_suspend()))
- swsusp_free();
+ 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:
restore_highmem();
device_power_up();
+Enable_irqs:
local_irq_enable();
return error;
}
* 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();
device_power_up();
local_irq_enable();
return error;
}
-
-/* More restore stuff */
-
-/*
- * Returns true if given address/order collides with any orig_address
- */
-static int does_collide_order(unsigned long addr, int order)
-{
- int i;
-
- for (i=0; i < (1<<order); i++)
- if (!PageNosaveFree(virt_to_page(addr + i * PAGE_SIZE)))
- return 1;
- return 0;
-}
-
-/**
- * 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.
- *
- * 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 ...
- */
-static void **eaten_memory = NULL;
-
-static inline void eat_page(void *page)
-{
- void **c;
-
- c = eaten_memory;
- eaten_memory = page;
- *eaten_memory = c;
-}
-
-static unsigned long get_usable_page(unsigned gfp_mask)
-{
- unsigned long m;
-
- m = get_zeroed_page(gfp_mask);
- while (does_collide_order(m, 0)) {
- eat_page((void *)m);
- m = get_zeroed_page(gfp_mask);
- if (!m)
- break;
- }
- return m;
-}
-
-static 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
- * pages later
- */
-
-static int check_pagedir(struct pbe *pblist)
-{
- struct pbe *p;
-
- /* This is necessary, so that we can free allocated pages
- * in case of failure
- */
- for_each_pbe (p, pblist)
- p->address = 0UL;
-
- for_each_pbe (p, pblist) {
- p->address = get_usable_page(GFP_ATOMIC);
- if (!p->address)
- return -ENOMEM;
- }
- return 0;
-}
-
-/**
- * swsusp_pagedir_relocate - It is possible, that some memory pages
- * occupied by the list of PBEs collide with pages where we're going to
- * restore from the loaded pages later. We relocate them here.
- */
-
-static struct pbe * swsusp_pagedir_relocate(struct pbe *pblist)
-{
- struct zone *zone;
- unsigned long zone_pfn;
- struct pbe *pbpage, *tail, *p;
- void *m;
- int rel = 0, error = 0;
-
- if (!pblist) /* a sanity check */
- return NULL;
-
- pr_debug("swsusp: Relocating pagedir (%lu pages to check)\n",
- swsusp_info.pagedir_pages);
-
- /* Set page flags */
-
- for_each_zone(zone) {
- for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
- SetPageNosaveFree(pfn_to_page(zone_pfn +
- zone->zone_start_pfn));
- }
-
- /* Clear orig addresses */
-
- for_each_pbe (p, pblist)
- ClearPageNosaveFree(virt_to_page(p->orig_address));
-
- tail = pblist + PB_PAGE_SKIP;
-
- /* Relocate colliding pages */
-
- for_each_pb_page (pbpage, pblist) {
- if (does_collide_order((unsigned long)pbpage, 0)) {
- m = (void *)get_usable_page(GFP_ATOMIC | __GFP_COLD);
- if (!m) {
- error = -ENOMEM;
- break;
- }
- 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;
-
- rel++;
- }
- tail = pbpage + PB_PAGE_SKIP;
- }
-
- if (error) {
- printk("\nswsusp: Out of memory\n\n");
- free_pagedir(pblist);
- free_eaten_memory();
- pblist = NULL;
- }
- else
- printk("swsusp: Relocated %d pages\n", rel);
-
- return pblist;
-}
-
-/*
- * Using bio to read from swap.
- * This code requires a bit more work than just using buffer heads
- * but, it is the recommended way for 2.5/2.6.
- * The following are to signal the beginning and end of I/O. Bios
- * finish asynchronously, while we want them to happen synchronously.
- * A simple atomic_t, and a wait loop take care of this problem.
- */
-
-static atomic_t io_done = ATOMIC_INIT(0);
-
-static int end_io(struct bio * bio, unsigned int num, int err)
-{
- if (!test_bit(BIO_UPTODATE, &bio->bi_flags))
- panic("I/O error reading memory image");
- atomic_set(&io_done, 0);
- return 0;
-}
-
-static struct block_device * resume_bdev;
-
-/**
- * submit - submit BIO request.
- * @rw: READ or WRITE.
- * @off physical offset of page.
- * @page: page we're reading or writing.
- *
- * Straight from the textbook - allocate and initialize the bio.
- * If we're writing, make sure the page is marked as dirty.
- * Then submit it and wait.
- */
-
-static int submit(int rw, pgoff_t page_off, void * page)
-{
- int error = 0;
- struct bio * bio;
-
- bio = bio_alloc(GFP_ATOMIC, 1);
- if (!bio)
- return -ENOMEM;
- bio->bi_sector = page_off * (PAGE_SIZE >> 9);
- bio_get(bio);
- bio->bi_bdev = resume_bdev;
- bio->bi_end_io = end_io;
-
- if (bio_add_page(bio, virt_to_page(page), PAGE_SIZE, 0) < PAGE_SIZE) {
- printk("swsusp: ERROR: adding page to bio at %ld\n",page_off);
- error = -EFAULT;
- goto Done;
- }
-
- if (rw == WRITE)
- bio_set_pages_dirty(bio);
-
- atomic_set(&io_done, 1);
- submit_bio(rw | (1 << BIO_RW_SYNC), bio);
- while (atomic_read(&io_done))
- yield();
-
- Done:
- bio_put(bio);
- return error;
-}
-
-static int bio_read_page(pgoff_t page_off, void * page)
-{
- return submit(READ, page_off, page);
-}
-
-static int bio_write_page(pgoff_t page_off, void * page)
-{
- return submit(WRITE, page_off, page);
-}
-
-/*
- * Sanity check if this image makes sense with this kernel/swap context
- * I really don't think that it's foolproof but more than nothing..
- */
-
-static const char * sanity_check(void)
-{
- dump_info();
- if(swsusp_info.version_code != LINUX_VERSION_CODE)
- return "kernel version";
- if(swsusp_info.num_physpages != num_physpages)
- return "memory size";
- if (strcmp(swsusp_info.uts.sysname,system_utsname.sysname))
- return "system type";
- if (strcmp(swsusp_info.uts.release,system_utsname.release))
- return "kernel release";
- if (strcmp(swsusp_info.uts.version,system_utsname.version))
- return "version";
- if (strcmp(swsusp_info.uts.machine,system_utsname.machine))
- return "machine";
- if(swsusp_info.cpus != num_online_cpus())
- return "number of cpus";
- return NULL;
-}
-
-
-static int check_header(void)
-{
- const char * reason = NULL;
- int error;
-
- if ((error = bio_read_page(swp_offset(swsusp_header.swsusp_info), &swsusp_info)))
- return error;
-
- /* Is this same machine? */
- if ((reason = sanity_check())) {
- printk(KERN_ERR "swsusp: Resume mismatch: %s\n",reason);
- return -EPERM;
- }
- nr_copy_pages = swsusp_info.image_pages;
- return error;
-}
-
-static int check_sig(void)
-{
- int error;
-
- memset(&swsusp_header, 0, sizeof(swsusp_header));
- if ((error = bio_read_page(0, &swsusp_header)))
- return error;
- if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) {
- memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10);
-
- /*
- * Reset swap signature now.
- */
- error = bio_write_page(0, &swsusp_header);
- } else {
- printk(KERN_ERR "swsusp: Suspend partition has wrong signature?\n");
- return -EINVAL;
- }
- if (!error)
- pr_debug("swsusp: Signature found, resuming\n");
- return error;
-}
-
-/**
- * data_read - Read image pages from swap.
- *
- * You do not need to check for overlaps, check_pagedir()
- * already did that.
- */
-
-static int data_read(struct pbe *pblist)
-{
- struct pbe * p;
- int error = 0;
- int i = 0;
- int mod = swsusp_info.image_pages / 100;
-
- if (!mod)
- mod = 1;
-
- printk("swsusp: Reading image data (%lu pages): ",
- swsusp_info.image_pages);
-
- for_each_pbe (p, pblist) {
- if (!(i % mod))
- printk("\b\b\b\b%3d%%", i / mod);
-
- error = bio_read_page(swp_offset(p->swap_address),
- (void *)p->address);
- if (error)
- return error;
-
- i++;
- }
- printk("\b\b\b\bdone\n");
- return error;
-}
-
-extern dev_t name_to_dev_t(const char *line);
-
-/**
- * read_pagedir - Read page backup list pages from swap
- */
-
-static int read_pagedir(struct pbe *pblist)
-{
- struct pbe *pbpage, *p;
- unsigned i = 0;
- int error;
-
- if (!pblist)
- return -EFAULT;
-
- printk("swsusp: Reading pagedir (%lu pages)\n",
- swsusp_info.pagedir_pages);
-
- for_each_pb_page (pbpage, pblist) {
- unsigned long offset = swp_offset(swsusp_info.pagedir[i++]);
-
- error = -EFAULT;
- if (offset) {
- p = (pbpage + PB_PAGE_SKIP)->next;
- error = bio_read_page(offset, (void *)pbpage);
- (pbpage + PB_PAGE_SKIP)->next = p;
- }
- if (error)
- break;
- }
-
- if (error)
- free_page((unsigned long)pblist);
-
- BUG_ON(i != swsusp_info.pagedir_pages);
-
- return error;
-}
-
-
-static int check_suspend_image(void)
-{
- int error = 0;
-
- if ((error = check_sig()))
- return error;
-
- if ((error = check_header()))
- return error;
-
- return 0;
-}
-
-static int read_suspend_image(void)
-{
- int error = 0;
- struct pbe *p;
-
- if (!(p = alloc_pagedir(nr_copy_pages)))
- return -ENOMEM;
-
- if ((error = read_pagedir(p)))
- return error;
-
- create_pbe_list(p, nr_copy_pages);
-
- if (!(pagedir_nosave = swsusp_pagedir_relocate(p)))
- return -ENOMEM;
-
- /* Allocate memory for the image and read the data from swap */
-
- error = check_pagedir(pagedir_nosave);
- free_eaten_memory();
- if (!error)
- error = data_read(pagedir_nosave);
-
- if (error) { /* We fail cleanly */
- for_each_pbe (p, pagedir_nosave)
- if (p->address) {
- free_page(p->address);
- p->address = 0UL;
- }
- free_pagedir(pagedir_nosave);
- }
- return error;
-}
-
-/**
- * swsusp_check - Check for saved image in swap
- */
-
-int swsusp_check(void)
-{
- int error;
-
- if (!swsusp_resume_device) {
- if (!strlen(resume_file))
- return -ENOENT;
- swsusp_resume_device = name_to_dev_t(resume_file);
- pr_debug("swsusp: Resume From Partition %s\n", resume_file);
- } else {
- pr_debug("swsusp: Resume From Partition %d:%d\n",
- MAJOR(swsusp_resume_device), MINOR(swsusp_resume_device));
- }
-
- resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ);
- if (!IS_ERR(resume_bdev)) {
- set_blocksize(resume_bdev, PAGE_SIZE);
- error = check_suspend_image();
- if (error)
- blkdev_put(resume_bdev);
- } else
- error = PTR_ERR(resume_bdev);
-
- if (!error)
- pr_debug("swsusp: resume file found\n");
- else
- pr_debug("swsusp: Error %d check for resume file\n", error);
- return error;
-}
-
-/**
- * swsusp_read - Read saved image from swap.
- */
-
-int swsusp_read(void)
-{
- int error;
-
- if (IS_ERR(resume_bdev)) {
- pr_debug("swsusp: block device not initialised\n");
- return PTR_ERR(resume_bdev);
- }
-
- error = read_suspend_image();
- blkdev_put(resume_bdev);
-
- if (!error)
- pr_debug("swsusp: Reading resume file was successful\n");
- else
- pr_debug("swsusp: Error %d resuming\n", error);
- return error;
-}
-
-/**
- * swsusp_close - close swap device.
- */
-
-void swsusp_close(void)
-{
- if (IS_ERR(resume_bdev)) {
- pr_debug("swsusp: block device not initialised\n");
- return;
- }
-
- blkdev_put(resume_bdev);
-}
git://git.onelab.eu / linux-2.6.git / blobdiff