/*
* 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.
*
* 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 <asm/uaccess.h>
-#include <asm/mmu_context.h>
-#include <asm/pgtable.h>
-#include <asm/io.h>
-
#include "power.h"
-unsigned char software_suspend_enabled = 0;
-
-#define NORESUME 1
-#define RESUME_SPECIFIED 2
-
-/* References to section boundaries */
-extern char __nosave_begin, __nosave_end;
-
-extern int is_head_of_free_region(struct page *);
-
-/* Locks */
-spinlock_t suspend_pagedir_lock __nosavedata = SPIN_LOCK_UNLOCKED;
-
-/* Variables to be preserved over suspend */
-static int pagedir_order_check;
-static int nr_copy_pages_check;
-
-static int resume_status;
-static char resume_file[256] = ""; /* For resume= kernel option */
-static dev_t resume_device;
-/* 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;
-static int pagedir_order __nosavedata = 0;
-
-struct link {
- char dummy[PAGE_SIZE - sizeof(swp_entry_t)];
- swp_entry_t next;
-};
-
-union diskpage {
- union swap_header swh;
- struct link link;
- struct suspend_header sh;
-};
-
/*
- * XXX: We try to keep some more pages free so that I/O operations succeed
- * without paging. Might this be more?
+ * 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.
*/
-#define PAGES_FOR_IO 512
+unsigned long image_size = 500 * 1024 * 1024;
-static const char name_suspend[] = "Suspend Machine: ";
-static const char name_resume[] = "Resume Machine: ";
+int in_suspend __nosavedata = 0;
-/*
- * Debug
- */
-#define DEBUG_DEFAULT
-#undef DEBUG_PROCESS
-#undef DEBUG_SLOW
-#define TEST_SWSUSP 0 /* Set to 1 to reboot instead of halt machine after suspension */
-
-#ifdef DEBUG_DEFAULT
-# define PRINTK(f, a...) printk(f, ## a)
-#else
-# define PRINTK(f, a...) do { } while(0)
-#endif
-
-#ifdef DEBUG_SLOW
-#define MDELAY(a) mdelay(a)
+#ifdef CONFIG_HIGHMEM
+unsigned int count_highmem_pages(void);
+int save_highmem(void);
+int restore_highmem(void);
#else
-#define MDELAY(a) do { } while(0)
+static int save_highmem(void) { return 0; }
+static int restore_highmem(void) { return 0; }
+static unsigned int count_highmem_pages(void) { return 0; }
#endif
-/*
- * Saving part...
- */
-
-static __inline__ int fill_suspend_header(struct suspend_header *sh)
-{
- memset((char *)sh, 0, sizeof(*sh));
-
- sh->version_code = LINUX_VERSION_CODE;
- sh->num_physpages = num_physpages;
- strncpy(sh->machine, system_utsname.machine, 8);
- strncpy(sh->version, system_utsname.version, 20);
- /* FIXME: Is this bogus? --RR */
- sh->num_cpus = num_online_cpus();
- sh->page_size = PAGE_SIZE;
- sh->suspend_pagedir = pagedir_nosave;
- BUG_ON (pagedir_save != pagedir_nosave);
- sh->num_pbes = nr_copy_pages;
- /* TODO: needed? mounted fs' last mounted date comparison
- * [so they haven't been mounted since last suspend.
- * Maybe it isn't.] [we'd need to do this for _all_ fs-es]
- */
- return 0;
-}
-
-/* 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;
-#define MARK_SWAP_SUSPEND 0
-#define MARK_SWAP_RESUME 2
-
-static void mark_swapfiles(swp_entry_t prev, int mode)
-{
- swp_entry_t entry;
- union diskpage *cur;
- struct page *page;
-
- if (root_swap == 0xFFFF) /* ignored */
- return;
-
- page = alloc_page(GFP_ATOMIC);
- if (!page)
- panic("Out of memory in mark_swapfiles");
- cur = page_address(page);
- /* XXX: this is dirty hack to get first page of swap file */
- entry = swp_entry(root_swap, 0);
- rw_swap_page_sync(READ, entry, page);
-
- if (mode == MARK_SWAP_RESUME) {
- if (!memcmp("S1",cur->swh.magic.magic,2))
- memcpy(cur->swh.magic.magic,"SWAP-SPACE",10);
- else if (!memcmp("S2",cur->swh.magic.magic,2))
- memcpy(cur->swh.magic.magic,"SWAPSPACE2",10);
- else printk("%sUnable to find suspended-data signature (%.10s - misspelled?\n",
- name_resume, cur->swh.magic.magic);
- } else {
- if ((!memcmp("SWAP-SPACE",cur->swh.magic.magic,10)))
- memcpy(cur->swh.magic.magic,"S1SUSP....",10);
- else if ((!memcmp("SWAPSPACE2",cur->swh.magic.magic,10)))
- memcpy(cur->swh.magic.magic,"S2SUSP....",10);
- else panic("\nSwapspace is not swapspace (%.10s)\n", cur->swh.magic.magic);
- cur->link.next = prev; /* prev is the first/last swap page of the resume area */
- /* link.next lies *no more* in last 4/8 bytes of magic */
- }
- rw_swap_page_sync(WRITE, entry, page);
- __free_page(page);
-}
-
-
-/*
- * 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) &&
- resume_device == MKDEV(imajor(inode), iminor(inode));
-}
-
-static void read_swapfiles(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();
-}
-
-static void lock_swapdevices(void) /* This is called after saving image so modification
- will be lost after resume... and that's what we want. */
-{
- int i;
-
- swap_list_lock();
- for(i = 0; i< MAX_SWAPFILES; i++)
- if(swapfile_used[i] == SWAPFILE_IGNORED) {
- swap_info[i].flags ^= 0xFF; /* we make the device unusable. A new call to
- lock_swapdevices can unlock the devices. */
- }
- swap_list_unlock();
-}
-
/**
- * write_suspend_image - Write entire image to disk.
- *
- * After writing suspend signature to the disk, suspend may no
- * longer fail: we have ready-to-run image in swap, and rollback
- * would happen on next reboot -- corrupting data.
+ * The following functions are used for tracing the allocated
+ * swap pages, so that they can be freed in case of an error.
*
- * Note: The buffer we allocate to use to write the suspend header is
- * not freed; its not needed since the system is going down anyway
- * (plus it causes an oops and I'm lazy^H^H^H^Htoo busy).
+ * The functions operate on a linked bitmap structure defined
+ * in power.h
*/
-static int write_suspend_image(void)
-{
- int i;
- swp_entry_t entry, prev = { 0 };
- int nr_pgdir_pages = SUSPEND_PD_PAGES(nr_copy_pages);
- union diskpage *cur, *buffer = (union diskpage *)get_zeroed_page(GFP_ATOMIC);
- unsigned long address;
- struct page *page;
-
- if (!buffer)
- return -ENOMEM;
-
- printk( "Writing data to swap (%d pages): ", nr_copy_pages );
- for (i=0; i<nr_copy_pages; i++) {
- if (!(i%100))
- printk( "." );
- if (!(entry = get_swap_page()).val)
- panic("\nNot enough swapspace when writing data" );
-
- if (swapfile_used[swp_type(entry)] != SWAPFILE_SUSPEND)
- panic("\nPage %d: not enough swapspace on suspend device", i );
-
- address = (pagedir_nosave+i)->address;
- page = virt_to_page(address);
- rw_swap_page_sync(WRITE, entry, page);
- (pagedir_nosave+i)->swap_address = entry;
- }
- printk( "|\n" );
- printk( "Writing pagedir (%d pages): ", nr_pgdir_pages);
- for (i=0; i<nr_pgdir_pages; i++) {
- cur = (union diskpage *)((char *) pagedir_nosave)+i;
- BUG_ON ((char *) cur != (((char *) pagedir_nosave) + i*PAGE_SIZE));
- printk( "." );
- if (!(entry = get_swap_page()).val) {
- printk(KERN_CRIT "Not enough swapspace when writing pgdir\n" );
- panic("Don't know how to recover");
- free_page((unsigned long) buffer);
- return -ENOSPC;
- }
-
- if(swapfile_used[swp_type(entry)] != SWAPFILE_SUSPEND)
- panic("\nNot enough swapspace for pagedir on suspend device" );
-
- BUG_ON (sizeof(swp_entry_t) != sizeof(long));
- BUG_ON (PAGE_SIZE % sizeof(struct pbe));
-
- cur->link.next = prev;
- page = virt_to_page((unsigned long)cur);
- rw_swap_page_sync(WRITE, entry, page);
- prev = entry;
- }
- printk("H");
- BUG_ON (sizeof(struct suspend_header) > PAGE_SIZE-sizeof(swp_entry_t));
- BUG_ON (sizeof(union diskpage) != PAGE_SIZE);
- BUG_ON (sizeof(struct link) != PAGE_SIZE);
- if (!(entry = get_swap_page()).val)
- panic( "\nNot enough swapspace when writing header" );
- if (swapfile_used[swp_type(entry)] != SWAPFILE_SUSPEND)
- panic("\nNot enough swapspace for header on suspend device" );
-
- cur = (void *) buffer;
- if (fill_suspend_header(&cur->sh))
- BUG(); /* Not a BUG_ON(): we want fill_suspend_header to be called, always */
-
- cur->link.next = prev;
-
- page = virt_to_page((unsigned long)cur);
- rw_swap_page_sync(WRITE, entry, page);
- prev = entry;
-
- printk( "S" );
- mark_swapfiles(prev, MARK_SWAP_SUSPEND);
- printk( "|\n" );
-
- MDELAY(1000);
- return 0;
-}
-
-#ifdef CONFIG_HIGHMEM
-struct highmem_page {
- char *data;
- struct page *page;
- struct highmem_page *next;
-};
-struct highmem_page *highmem_copy = NULL;
-
-static int save_highmem_zone(struct zone *zone)
-{
- unsigned long zone_pfn;
- 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;
- int chunk_size;
-
- 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;
- }
- if ((chunk_size = is_head_of_free_region(page))) {
- pfn += chunk_size - 1;
- zone_pfn += chunk_size - 1;
- 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;
-}
-
-static int save_highmem(void)
+void free_bitmap(struct bitmap_page *bitmap)
{
- struct zone *zone;
- int res = 0;
- for_each_zone(zone) {
- if (is_highmem(zone))
- res = save_highmem_zone(zone);
- if (res)
- return res;
- }
- return 0;
-}
-
-static int restore_highmem(void)
-{
- 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);
- }
- return 0;
-}
-#endif
-
-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);
-}
-
-/* if *pagedir_p != NULL it also copies the counted pages */
-static int count_and_copy_zone(struct zone *zone, struct pbe **pagedir_p)
-{
- unsigned long zone_pfn, chunk_size, nr_copy_pages = 0;
- struct pbe *pbe = *pagedir_p;
- 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%1000))
- printk(".");
- if (!pfn_valid(pfn))
- continue;
- page = pfn_to_page(pfn);
- BUG_ON(PageReserved(page) && PageNosave(page));
- if (PageNosave(page))
- continue;
- if (PageReserved(page) && pfn_is_nosave(pfn)) {
- PRINTK("[nosave pfn 0x%lx]", pfn);
- continue;
- }
- if ((chunk_size = is_head_of_free_region(page))) {
- pfn += chunk_size - 1;
- zone_pfn += chunk_size - 1;
- continue;
- }
- nr_copy_pages++;
- if (!pbe)
- continue;
- pbe->orig_address = (long) page_address(page);
- copy_page((void *)pbe->address, (void *)pbe->orig_address);
- pbe++;
- }
- *pagedir_p = pbe;
- return nr_copy_pages;
-}
-
-static int count_and_copy_data_pages(struct pbe *pagedir_p)
-{
- int nr_copy_pages = 0;
- struct zone *zone;
- for_each_zone(zone) {
- if (!is_highmem(zone))
- nr_copy_pages += count_and_copy_zone(zone, &pagedir_p);
- }
- return nr_copy_pages;
-}
-
-static void free_suspend_pagedir_zone(struct zone *zone, unsigned long pagedir)
-{
- unsigned long zone_pfn, pagedir_end, pagedir_pfn, pagedir_end_pfn;
- pagedir_end = pagedir + (PAGE_SIZE << pagedir_order);
- pagedir_pfn = __pa(pagedir) >> PAGE_SHIFT;
- pagedir_end_pfn = __pa(pagedir_end) >> PAGE_SHIFT;
- 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 (!TestClearPageNosave(page))
- continue;
- else if (pfn >= pagedir_pfn && pfn < pagedir_end_pfn)
- continue;
- __free_page(page);
- }
-}
+ struct bitmap_page *bp;
-static void free_suspend_pagedir(unsigned long this_pagedir)
-{
- struct zone *zone;
- for_each_zone(zone) {
- if (!is_highmem(zone))
- free_suspend_pagedir_zone(zone, this_pagedir);
+ while (bitmap) {
+ bp = bitmap->next;
+ free_page((unsigned long)bitmap);
+ bitmap = bp;
}
- free_pages(this_pagedir, pagedir_order);
}
-static suspend_pagedir_t *create_suspend_pagedir(int nr_copy_pages)
+struct bitmap_page *alloc_bitmap(unsigned int nr_bits)
{
- int i;
- suspend_pagedir_t *pagedir;
- struct pbe *p;
- struct page *page;
+ struct bitmap_page *bitmap, *bp;
+ unsigned int n;
- pagedir_order = get_bitmask_order(SUSPEND_PD_PAGES(nr_copy_pages));
-
- p = pagedir = (suspend_pagedir_t *)__get_free_pages(GFP_ATOMIC | __GFP_COLD, pagedir_order);
- if (!pagedir)
+ if (!nr_bits)
return NULL;
- page = virt_to_page(pagedir);
- for(i=0; i < 1<<pagedir_order; i++)
- SetPageNosave(page++);
-
- while(nr_copy_pages--) {
- p->address = get_zeroed_page(GFP_ATOMIC | __GFP_COLD);
- if (!p->address) {
- free_suspend_pagedir((unsigned long) pagedir);
+ 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;
}
- SetPageNosave(virt_to_page(p->address));
- p->orig_address = 0;
- p++;
- }
- return pagedir;
-}
-
-static int prepare_suspend_processes(void)
-{
- sys_sync(); /* Syncing needs pdflushd, so do it before stopping processes */
- if (freeze_processes()) {
- printk( KERN_ERR "Suspend failed: Not all processes stopped!\n" );
- thaw_processes();
- return 1;
}
- return 0;
-}
-
-/*
- * 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)
-{
- printk("Freeing memory: ");
- while (shrink_all_memory(10000))
- printk(".");
- printk("|\n");
+ return bitmap;
}
-static int suspend_prepare_image(void)
+static int bitmap_set(struct bitmap_page *bitmap, unsigned long bit)
{
- struct sysinfo i;
- unsigned int nr_needed_pages = 0;
+ unsigned int n;
- pagedir_nosave = NULL;
- printk( "/critical section: ");
-#ifdef CONFIG_HIGHMEM
- printk( "handling highmem" );
- if (save_highmem()) {
- printk(KERN_CRIT "%sNot enough free pages for highmem\n", name_suspend);
- return -ENOMEM;
- }
- printk(", ");
-#endif
-
- printk("counting pages to copy" );
- drain_local_pages();
- nr_copy_pages = count_and_copy_data_pages(NULL);
- nr_needed_pages = nr_copy_pages + PAGES_FOR_IO;
-
- printk(" (pages needed: %d+%d=%d free: %d)\n",nr_copy_pages,PAGES_FOR_IO,nr_needed_pages,nr_free_pages());
- if(nr_free_pages() < nr_needed_pages) {
- printk(KERN_CRIT "%sCouldn't get enough free pages, on %d pages short\n",
- name_suspend, nr_needed_pages-nr_free_pages());
- root_swap = 0xFFFF;
- return -ENOMEM;
- }
- si_swapinfo(&i); /* FIXME: si_swapinfo(&i) returns all swap devices information.
- We should only consider resume_device. */
- if (i.freeswap < nr_needed_pages) {
- printk(KERN_CRIT "%sThere's not enough swap space available, on %ld pages short\n",
- name_suspend, nr_needed_pages-i.freeswap);
- return -ENOSPC;
+ n = BITMAP_PAGE_BITS;
+ while (bitmap && n <= bit) {
+ n += BITMAP_PAGE_BITS;
+ bitmap = bitmap->next;
}
-
- PRINTK( "Alloc pagedir\n" );
- pagedir_save = pagedir_nosave = create_suspend_pagedir(nr_copy_pages);
- if (!pagedir_nosave) {
- /* Pagedir is big, one-chunk allocation. It is easily possible for this allocation to fail */
- printk(KERN_CRIT "%sCouldn't allocate continuous pagedir\n", name_suspend);
- return -ENOMEM;
- }
- nr_copy_pages_check = nr_copy_pages;
- pagedir_order_check = pagedir_order;
-
- drain_local_pages(); /* During allocating of suspend pagedir, new cold pages may appear. Kill them */
- if (nr_copy_pages != count_and_copy_data_pages(pagedir_nosave)) /* copy */
- BUG();
-
- /*
- * 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( "critical section/: done (%d pages copied)\n", nr_copy_pages );
+ 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;
}
-static void suspend_save_image(void)
+unsigned long alloc_swap_page(int swap, struct bitmap_page *bitmap)
{
- device_resume();
-
- lock_swapdevices();
- write_suspend_image();
- lock_swapdevices(); /* This will unlock ignored swap devices since writing is finished */
+ unsigned long offset;
- /* 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.)
- */
-}
-
-static void suspend_power_down(void)
-{
- extern int C_A_D;
- C_A_D = 0;
- printk(KERN_EMERG "%s%s Trying to power down.\n", name_suspend, TEST_SWSUSP ? "Disable TEST_SWSUSP. NOT ": "");
-#ifdef CONFIG_VT
- PRINTK(KERN_EMERG "shift_state: %04x\n", shift_state);
- mdelay(1000);
- if (TEST_SWSUSP ^ (!!(shift_state & (1 << KG_CTRL))))
- machine_restart(NULL);
- else
-#endif
- {
- device_shutdown();
- machine_power_off();
- }
-
- printk(KERN_EMERG "%sProbably not capable for powerdown. System halted.\n", name_suspend);
- machine_halt();
- while (1);
- /* NOTREACHED */
-}
-
-/*
- * Magic happens here
- */
-
-asmlinkage void do_magic_resume_1(void)
-{
- barrier();
- mb();
- spin_lock_irq(&suspend_pagedir_lock); /* Done to disable interrupts */
-
- device_power_down(4);
- PRINTK( "Waiting for DMAs to settle down...\n");
- mdelay(1000); /* We do not want some readahead with DMA to corrupt our memory, right?
- Do it with disabled interrupts for best effect. That way, if some
- driver scheduled DMA, we have good chance for DMA to finish ;-). */
-}
-
-asmlinkage void do_magic_resume_2(void)
-{
- BUG_ON (nr_copy_pages_check != nr_copy_pages);
- BUG_ON (pagedir_order_check != pagedir_order);
-
- __flush_tlb_global(); /* Even mappings of "global" things (vmalloc) need to be fixed */
-
- PRINTK( "Freeing prev allocated pagedir\n" );
- free_suspend_pagedir((unsigned long) pagedir_save);
-
-#ifdef CONFIG_HIGHMEM
- printk( "Restoring highmem\n" );
- restore_highmem();
-#endif
- printk("done, devices\n");
-
- device_power_up();
- spin_unlock_irq(&suspend_pagedir_lock);
- device_resume();
-
- /* Fixme: this is too late; we should do this ASAP to avoid "infinite reboots" problem */
- PRINTK( "Fixing swap signatures... " );
- mark_swapfiles(((swp_entry_t) {0}), MARK_SWAP_RESUME);
- PRINTK( "ok\n" );
-
-#ifdef SUSPEND_CONSOLE
- acquire_console_sem();
- update_screen(fg_console);
- release_console_sem();
-#endif
-}
-
-/* do_magic() is implemented in arch/?/kernel/suspend_asm.S, and basically does:
-
- if (!resume) {
- do_magic_suspend_1();
- save_processor_state();
- SAVE_REGISTERS
- do_magic_suspend_2();
- return;
- }
- GO_TO_SWAPPER_PAGE_TABLES
- do_magic_resume_1();
- COPY_PAGES_BACK
- RESTORE_REGISTERS
- restore_processor_state();
- do_magic_resume_2();
-
- */
-
-asmlinkage void do_magic_suspend_1(void)
-{
- mb();
- barrier();
- BUG_ON(in_atomic());
- spin_lock_irq(&suspend_pagedir_lock);
-}
-
-asmlinkage void do_magic_suspend_2(void)
-{
- int is_problem;
- read_swapfiles();
- device_power_down(4);
- is_problem = suspend_prepare_image();
- device_power_up();
- spin_unlock_irq(&suspend_pagedir_lock);
- if (!is_problem) {
- kernel_fpu_end(); /* save_processor_state() does kernel_fpu_begin, and we need to revert it in order to pass in_atomic() checks */
- BUG_ON(in_atomic());
- suspend_save_image();
- suspend_power_down(); /* FIXME: if suspend_power_down is commented out, console is lost after few suspends ?! */
+ offset = swp_offset(get_swap_page_of_type(swap));
+ if (offset) {
+ if (bitmap_set(bitmap, offset)) {
+ swap_free(swp_entry(swap, offset));
+ offset = 0;
+ }
}
-
- printk(KERN_EMERG "%sSuspend failed, trying to recover...\n", name_suspend);
- MDELAY(1000); /* So user can wait and report us messages if armageddon comes :-) */
-
- barrier();
- mb();
- spin_lock_irq(&suspend_pagedir_lock); /* Done to disable interrupts */
- mdelay(1000);
-
- free_pages((unsigned long) pagedir_nosave, pagedir_order);
- spin_unlock_irq(&suspend_pagedir_lock);
-
- device_resume();
- PRINTK( "Fixing swap signatures... " );
- mark_swapfiles(((swp_entry_t) {0}), MARK_SWAP_RESUME);
- PRINTK( "ok\n" );
-}
-
-/*
- * This is main interface to the outside world. It needs to be
- * called from process context.
- */
-int software_suspend(void)
-{
- int res;
- if (!software_suspend_enabled)
- return -EAGAIN;
-
- software_suspend_enabled = 0;
- might_sleep();
-
- if (arch_prepare_suspend()) {
- printk("%sArchitecture failed to prepare\n", name_suspend);
- return -EPERM;
- }
- if (pm_prepare_console())
- printk( "%sCan't allocate a console... proceeding\n", name_suspend);
- if (!prepare_suspend_processes()) {
-
- /* At this point, all user processes and "dangerous"
- kernel threads are stopped. Free some memory, as we
- need half of memory free. */
-
- free_some_memory();
-
- /* Save state of all device drivers, and stop them. */
- if ((res = device_suspend(4))==0)
- /* If stopping device drivers worked, we proceed basically into
- * suspend_save_image.
- *
- * do_magic(0) returns after system is resumed.
- *
- * do_magic() copies all "used" memory to "free" memory, then
- * unsuspends all device drivers, and writes memory to disk
- * using normal kernel mechanism.
- */
- do_magic(0);
- thaw_processes();
- } else
- res = -EBUSY;
- software_suspend_enabled = 1;
- MDELAY(1000);
- pm_restore_console();
- return res;
+ return offset;
}
-/* More restore stuff */
-
-/* FIXME: Why not memcpy(to, from, 1<<pagedir_order*PAGE_SIZE)? */
-static void copy_pagedir(suspend_pagedir_t *to, suspend_pagedir_t *from)
+void free_all_swap_pages(int swap, struct bitmap_page *bitmap)
{
- int i;
- char *topointer=(char *)to, *frompointer=(char *)from;
+ unsigned int bit, n;
+ unsigned long test;
- for(i=0; i < 1 << pagedir_order; i++) {
- copy_page(topointer, frompointer);
- topointer += PAGE_SIZE;
- frompointer += PAGE_SIZE;
+ 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;
}
}
-#define does_collide(addr) does_collide_order(pagedir_nosave, addr, 0)
-
-/*
- * Returns true if given address/order collides with any orig_address
+/**
+ * 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.
*/
-static int does_collide_order(suspend_pagedir_t *pagedir, unsigned long addr,
- int order)
-{
- int i;
- unsigned long addre = addr + (PAGE_SIZE<<order);
-
- for(i=0; i < nr_copy_pages; i++)
- if((pagedir+i)->orig_address >= addr &&
- (pagedir+i)->orig_address < addre)
- return 1;
- return 0;
-}
+#define SHRINK_BITE 10000
-/*
- * We check here that pagedir & pages it points to won't collide with pages
- * where we're going to restore from the loaded pages later
- */
-static int check_pagedir(void)
+int swsusp_shrink_memory(void)
{
- int i;
-
- for(i=0; i < nr_copy_pages; i++) {
- unsigned long addr;
-
- do {
- addr = get_zeroed_page(GFP_ATOMIC);
- if(!addr)
+ long size, tmp;
+ struct zone *zone;
+ unsigned long pages = 0;
+ unsigned int i = 0;
+ char *p = "-\\|/";
+
+ 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;
- } while (does_collide(addr));
-
- (pagedir_nosave+i)->address = addr;
- }
- return 0;
-}
-
-static int relocate_pagedir(void)
-{
- /*
- * We have to avoid recursion (not to overflow kernel stack),
- * and that's why code looks pretty cryptic
- */
- suspend_pagedir_t *new_pagedir, *old_pagedir = pagedir_nosave;
- void **eaten_memory = NULL;
- void **c = eaten_memory, *m, *f;
-
- printk("Relocating pagedir");
-
- if(!does_collide_order(old_pagedir, (unsigned long)old_pagedir, pagedir_order)) {
- printk("not necessary\n");
- return 0;
- }
-
- while ((m = (void *) __get_free_pages(GFP_ATOMIC, pagedir_order))) {
- memset(m, 0, PAGE_SIZE);
- if (!does_collide_order(old_pagedir, (unsigned long)m, pagedir_order))
- break;
- eaten_memory = m;
- printk( "." );
- *eaten_memory = c;
- c = eaten_memory;
- }
-
- if (!m)
- return -ENOMEM;
-
- pagedir_nosave = new_pagedir = m;
- copy_pagedir(new_pagedir, old_pagedir);
-
- c = eaten_memory;
- while(c) {
- printk(":");
- f = *c;
- c = *c;
- if (f)
- free_pages((unsigned long)f, pagedir_order);
- }
- printk("|\n");
- return 0;
-}
-
-/*
- * 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 int sanity_check_failed(char *reason)
-{
- printk(KERN_ERR "%s%s\n", name_resume, reason);
- return -EPERM;
-}
-
-static int sanity_check(struct suspend_header *sh)
-{
- if (sh->version_code != LINUX_VERSION_CODE)
- return sanity_check_failed("Incorrect kernel version");
- if (sh->num_physpages != num_physpages)
- return sanity_check_failed("Incorrect memory size");
- if (strncmp(sh->machine, system_utsname.machine, 8))
- return sanity_check_failed("Incorrect machine type");
- if (strncmp(sh->version, system_utsname.version, 20))
- return sanity_check_failed("Incorrect version");
- if (sh->num_cpus != num_online_cpus())
- return sanity_check_failed("Incorrect number of cpus");
- if (sh->page_size != PAGE_SIZE)
- return sanity_check_failed("Incorrect PAGE_SIZE");
- return 0;
-}
-
-static int bdev_read_page(struct block_device *bdev, long pos, void *buf)
-{
- struct buffer_head *bh;
- BUG_ON (pos%PAGE_SIZE);
- bh = __bread(bdev, pos/PAGE_SIZE, PAGE_SIZE);
- if (!bh || (!bh->b_data)) {
- return -1;
- }
- memcpy(buf, bh->b_data, PAGE_SIZE); /* FIXME: may need kmap() */
- BUG_ON(!buffer_uptodate(bh));
- brelse(bh);
- return 0;
-}
+ 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);
-static int bdev_write_page(struct block_device *bdev, long pos, void *buf)
-{
-#if 0
- struct buffer_head *bh;
- BUG_ON (pos%PAGE_SIZE);
- bh = __bread(bdev, pos/PAGE_SIZE, PAGE_SIZE);
- if (!bh || (!bh->b_data)) {
- return -1;
- }
- memcpy(bh->b_data, buf, PAGE_SIZE); /* FIXME: may need kmap() */
- BUG_ON(!buffer_uptodate(bh));
- generic_make_request(WRITE, bh);
- if (!buffer_uptodate(bh))
- printk(KERN_CRIT "%sWarning %s: Fixing swap signatures unsuccessful...\n", name_resume, resume_file);
- wait_on_buffer(bh);
- brelse(bh);
- return 0;
-#endif
- printk(KERN_CRIT "%sWarning %s: Fixing swap signatures unimplemented...\n", name_resume, resume_file);
return 0;
}
-extern dev_t __init name_to_dev_t(const char *line);
-
-static int __init __read_suspend_image(struct block_device *bdev, union diskpage *cur, int noresume)
+int swsusp_suspend(void)
{
- swp_entry_t next;
- int i, nr_pgdir_pages;
-
-#define PREPARENEXT \
- { next = cur->link.next; \
- next.val = swp_offset(next) * PAGE_SIZE; \
- }
-
- if (bdev_read_page(bdev, 0, cur)) return -EIO;
+ int error;
- if ((!memcmp("SWAP-SPACE",cur->swh.magic.magic,10)) ||
- (!memcmp("SWAPSPACE2",cur->swh.magic.magic,10))) {
- printk(KERN_ERR "%sThis is normal swap space\n", name_resume );
- return -EINVAL;
+ if ((error = arch_prepare_suspend()))
+ return error;
+ local_irq_disable();
+ /* At this point, device_suspend() has been called, but *not*
+ * device_power_down(). We *must* device_power_down() now.
+ * Otherwise, drivers for some devices (e.g. interrupt controllers)
+ * become desynchronized with the actual state of the hardware
+ * at resume time, and evil weirdness ensues.
+ */
+ if ((error = device_power_down(PMSG_FREEZE))) {
+ printk(KERN_ERR "Some devices failed to power down, aborting suspend\n");
+ goto Enable_irqs;
}
- PREPARENEXT; /* We have to read next position before we overwrite it */
-
- if (!memcmp("S1",cur->swh.magic.magic,2))
- memcpy(cur->swh.magic.magic,"SWAP-SPACE",10);
- else if (!memcmp("S2",cur->swh.magic.magic,2))
- memcpy(cur->swh.magic.magic,"SWAPSPACE2",10);
- else {
- if (noresume)
- return -EINVAL;
- panic("%sUnable to find suspended-data signature (%.10s - misspelled?\n",
- name_resume, cur->swh.magic.magic);
+ if ((error = save_highmem())) {
+ printk(KERN_ERR "swsusp: Not enough free pages for highmem\n");
+ goto Restore_highmem;
}
- if (noresume) {
- /* We don't do a sanity check here: we want to restore the swap
- whatever version of kernel made the suspend image;
- We need to write swap, but swap is *not* enabled so
- we must write the device directly */
- printk("%s: Fixing swap signatures %s...\n", name_resume, resume_file);
- bdev_write_page(bdev, 0, cur);
- }
-
- printk( "%sSignature found, resuming\n", name_resume );
- MDELAY(1000);
-
- if (bdev_read_page(bdev, next.val, cur)) return -EIO;
- if (sanity_check(&cur->sh)) /* Is this same machine? */
- return -EPERM;
- PREPARENEXT;
-
- pagedir_save = cur->sh.suspend_pagedir;
- nr_copy_pages = cur->sh.num_pbes;
- nr_pgdir_pages = SUSPEND_PD_PAGES(nr_copy_pages);
- pagedir_order = get_bitmask_order(nr_pgdir_pages);
-
- pagedir_nosave = (suspend_pagedir_t *)__get_free_pages(GFP_ATOMIC, pagedir_order);
- if (!pagedir_nosave)
- return -ENOMEM;
- PRINTK( "%sReading pagedir, ", name_resume );
-
- /* We get pages in reverse order of saving! */
- for (i=nr_pgdir_pages-1; i>=0; i--) {
- BUG_ON (!next.val);
- cur = (union diskpage *)((char *) pagedir_nosave)+i;
- if (bdev_read_page(bdev, next.val, cur)) return -EIO;
- PREPARENEXT;
- }
- BUG_ON (next.val);
-
- if (relocate_pagedir())
- return -ENOMEM;
- if (check_pagedir())
- return -ENOMEM;
-
- printk( "Reading image data (%d pages): ", nr_copy_pages );
- for(i=0; i < nr_copy_pages; i++) {
- swp_entry_t swap_address = (pagedir_nosave+i)->swap_address;
- if (!(i%100))
- printk( "." );
- /* You do not need to check for overlaps...
- ... check_pagedir already did this work */
- if (bdev_read_page(bdev, swp_offset(swap_address) * PAGE_SIZE, (char *)((pagedir_nosave+i)->address)))
- return -EIO;
- }
- printk( "|\n" );
- return 0;
+ save_processor_state();
+ if ((error = swsusp_arch_suspend()))
+ printk(KERN_ERR "Error %d suspending\n", error);
+ /* Restore control flow magically appears here */
+ restore_processor_state();
+Restore_highmem:
+ restore_highmem();
+ device_power_up();
+Enable_irqs:
+ local_irq_enable();
+ return error;
}
-static int __init read_suspend_image(const char * specialfile, int noresume)
+int swsusp_resume(void)
{
- union diskpage *cur;
- unsigned long scratch_page = 0;
int error;
- char b[BDEVNAME_SIZE];
-
- resume_device = name_to_dev_t(specialfile);
- scratch_page = get_zeroed_page(GFP_ATOMIC);
- cur = (void *) scratch_page;
- if (cur) {
- struct block_device *bdev;
- printk("Resuming from device %s\n",
- __bdevname(resume_device, b));
- bdev = open_by_devnum(resume_device, FMODE_READ);
- if (IS_ERR(bdev)) {
- error = PTR_ERR(bdev);
- } else {
- set_blocksize(bdev, PAGE_SIZE);
- error = __read_suspend_image(bdev, cur, noresume);
- blkdev_put(bdev);
- }
- } else error = -ENOMEM;
-
- if (scratch_page)
- free_page(scratch_page);
- switch (error) {
- case 0:
- PRINTK("Reading resume file was successful\n");
- break;
- case -EINVAL:
- break;
- case -EIO:
- printk( "%sI/O error\n", name_resume);
- break;
- case -ENOENT:
- printk( "%s%s: No such file or directory\n", name_resume, specialfile);
- break;
- case -ENOMEM:
- printk( "%sNot enough memory\n", name_resume);
- break;
- default:
- printk( "%sError %d resuming\n", name_resume, error );
- }
- MDELAY(1000);
+ local_irq_disable();
+ if (device_power_down(PMSG_FREEZE))
+ printk(KERN_ERR "Some devices failed to power down, very bad\n");
+ /* We'll ignore saved state, but this gets preempt count (etc) right */
+ save_processor_state();
+ error = swsusp_arch_resume();
+ /* Code below is only ever reached in case of failure. Otherwise
+ * 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;
}
-
-/**
- * software_resume - Resume from a saved image.
- *
- * Called as a late_initcall (so all devices are discovered and
- * initialized), we call swsusp to see if we have a saved image or not.
- * If so, we quiesce devices, then restore the saved image. We will
- * return above (in pm_suspend_disk() ) if everything goes well.
- * Otherwise, we fail gracefully and return to the normally
- * scheduled program.
- *
- */
-static int __init software_resume(void)
-{
- if (num_online_cpus() > 1) {
- printk(KERN_WARNING "Software Suspend has malfunctioning SMP support. Disabled :(\n");
- return -EINVAL;
- }
- /* We enable the possibility of machine suspend */
- software_suspend_enabled = 1;
- if (!resume_status)
- return 0;
-
- printk( "%s", name_resume );
- if (resume_status == NORESUME) {
- if(resume_file[0])
- read_suspend_image(resume_file, 1);
- printk( "disabled\n" );
- return 0;
- }
- MDELAY(1000);
-
- if (pm_prepare_console())
- printk("swsusp: Can't allocate a console... proceeding\n");
-
- if (!resume_file[0] && resume_status == RESUME_SPECIFIED) {
- printk( "suspension device unspecified\n" );
- return -EINVAL;
- }
-
- printk( "resuming from %s\n", resume_file);
- if (read_suspend_image(resume_file, 0))
- goto read_failure;
- device_suspend(4);
- do_magic(1);
- panic("This never returns");
-
-read_failure:
- pm_restore_console();
- return 0;
-}
-
-late_initcall(software_resume);
-
-static int __init resume_setup(char *str)
-{
- if (resume_status == NORESUME)
- return 1;
-
- strncpy( resume_file, str, 255 );
- resume_status = RESUME_SPECIFIED;
-
- return 1;
-}
-
-static int __init noresume_setup(char *str)
-{
- resume_status = NORESUME;
- return 1;
-}
-
-__setup("noresume", noresume_setup);
-__setup("resume=", resume_setup);
-
-EXPORT_SYMBOL(software_suspend);
-EXPORT_SYMBOL(software_suspend_enabled);