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-rw-r--r--kernel/power/pmdisk.c969
1 files changed, 969 insertions, 0 deletions
diff --git a/kernel/power/pmdisk.c b/kernel/power/pmdisk.c
new file mode 100644
index 000000000000..bb795b6dc537
--- /dev/null
+++ b/kernel/power/pmdisk.c
@@ -0,0 +1,969 @@
+/*
+ * linux/kernel/suspend.c
+ *
+ * This file is to realize architecture-independent
+ * machine suspend feature using pretty near only high-level routines
+ *
+ * Copyright (C) 1998-2001 Gabor Kuti <seasons@fornax.hu>
+ * Copyright (C) 1998,2001,2002 Pavel Machek <pavel@suse.cz>
+ *
+ * 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>:
+ * Support the possibility of hardware state restoring.
+ *
+ * Raph <grey.havens@earthling.net>:
+ * Support for preserving states of network devices and virtual console
+ * (including X and svgatextmode)
+ *
+ * Kurt Garloff <garloff@suse.de>:
+ * Straightened the critical function in order to prevent compilers from
+ * playing tricks with local variables.
+ *
+ * Andreas Mohr <a.mohr@mailto.de>
+ *
+ * Alex Badea <vampire@go.ro>:
+ * Fixed runaway init
+ *
+ * More state savers are welcome. Especially for the scsi layer...
+ *
+ * For TODOs,FIXMEs also look in Documentation/swsusp.txt
+ */
+
+#include <linux/mm.h>
+#include <linux/bio.h>
+#include <linux/suspend.h>
+#include <linux/version.h>
+#include <linux/reboot.h>
+#include <linux/device.h>
+#include <linux/swapops.h>
+#include <linux/bootmem.h>
+
+#include <asm/mmu_context.h>
+
+#include "power.h"
+
+
+extern int swsusp_arch_suspend(int resume);
+
+#define __ADDRESS(x) ((unsigned long) phys_to_virt(x))
+#define ADDRESS(x) __ADDRESS((x) << PAGE_SHIFT)
+#define ADDRESS2(x) __ADDRESS(__pa(x)) /* Needed for x86-64 where some pages are in memory twice */
+
+/* References to section boundaries */
+extern char __nosave_begin, __nosave_end;
+
+extern int is_head_of_free_region(struct page *);
+
+/* Variables to be preserved over suspend */
+static int pagedir_order_check;
+static int nr_copy_pages_check;
+
+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.
+ */
+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?
+ */
+#define PAGES_FOR_IO 512
+
+static const char name_suspend[] = "Suspend Machine: ";
+static const char name_resume[] = "Resume Machine: ";
+
+/*
+ * 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...)
+#endif
+
+#ifdef DEBUG_SLOW
+#define MDELAY(a) mdelay(a)
+#else
+#define MDELAY(a)
+#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);
+}
+
+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 (1) {
+// FIXME if(resume_device == swap_info[i].swap_device) {
+ swapfile_used[i] = SWAPFILE_SUSPEND;
+ root_swap = i;
+ } else {
+#if 0
+ printk( "Resume: device %s (%x != %x) ignored\n", swap_info[i].swap_file->d_name.name, swap_info[i].swap_device, resume_device );
+#endif
+ 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();
+}
+
+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;
+
+ 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);
+ 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))
+ panic("\nOut of memory while writing header");
+
+ 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);
+ free_page((unsigned long) buffer);
+ return 0;
+}
+
+/* if pagedir_p != NULL it also copies the counted pages */
+static int count_and_copy_data_pages(struct pbe *pagedir_p)
+{
+ int chunk_size;
+ int nr_copy_pages = 0;
+ int pfn;
+ struct page *page;
+
+ BUG_ON (max_pfn != num_physpages);
+
+ for (pfn = 0; pfn < max_pfn; pfn++) {
+ page = pfn_to_page(pfn);
+
+ if (!PageReserved(page)) {
+ if (PageNosave(page))
+ continue;
+
+ if ((chunk_size=is_head_of_free_region(page))!=0) {
+ pfn += chunk_size - 1;
+ continue;
+ }
+ } else if (PageReserved(page)) {
+ BUG_ON (PageNosave(page));
+
+ /*
+ * Just copy whole code segment. Hopefully it is not that big.
+ */
+ if ((ADDRESS(pfn) >= (unsigned long) ADDRESS2(&__nosave_begin)) &&
+ (ADDRESS(pfn) < (unsigned long) ADDRESS2(&__nosave_end))) {
+ PRINTK("[nosave %lx]", ADDRESS(pfn));
+ continue;
+ }
+ /* Hmm, perhaps copying all reserved pages is not too healthy as they may contain
+ critical bios data? */
+ } else BUG();
+
+ nr_copy_pages++;
+ if (pagedir_p) {
+ pagedir_p->orig_address = ADDRESS(pfn);
+ copy_page((void *) pagedir_p->address, (void *) pagedir_p->orig_address);
+ pagedir_p++;
+ }
+ }
+ return nr_copy_pages;
+}
+
+static void free_suspend_pagedir(unsigned long this_pagedir)
+{
+ struct page *page;
+ int pfn;
+ unsigned long this_pagedir_end = this_pagedir +
+ (PAGE_SIZE << pagedir_order);
+
+ for(pfn = 0; pfn < num_physpages; pfn++) {
+ page = pfn_to_page(pfn);
+ if (!TestClearPageNosave(page))
+ continue;
+
+ if (ADDRESS(pfn) >= this_pagedir && ADDRESS(pfn) < this_pagedir_end)
+ continue; /* old pagedir gets freed in one */
+
+ free_page(ADDRESS(pfn));
+ }
+ free_pages(this_pagedir, pagedir_order);
+}
+
+static suspend_pagedir_t *create_suspend_pagedir(int nr_copy_pages)
+{
+ int i;
+ suspend_pagedir_t *pagedir;
+ struct pbe *p;
+ struct page *page;
+
+ 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)
+ 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);
+ return NULL;
+ }
+ SetPageNosave(virt_to_page(p->address));
+ p->orig_address = 0;
+ p++;
+ }
+ return pagedir;
+}
+
+
+int swsusp_suspend(void)
+{
+ struct sysinfo i;
+ unsigned int nr_needed_pages = 0;
+
+ read_swapfiles();
+ drain_local_pages();
+
+ pagedir_nosave = NULL;
+ printk( "/critical section: Counting pages to copy" );
+ 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 1;
+ }
+ 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 1;
+ }
+
+ PRINTK( "Alloc pagedir\n" );
+ pagedir_save = pagedir_nosave = create_suspend_pagedir(nr_copy_pages);
+ if(!pagedir_nosave) {
+ /* Shouldn't happen */
+ printk(KERN_CRIT "%sCouldn't allocate enough pages\n",name_suspend);
+ panic("Really should not happen");
+ return 1;
+ }
+ 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 );
+ return 0;
+}
+
+
+/**
+ * suspend_save_image - Prepare and write saved image to swap.
+ *
+ * IRQs are re-enabled here so we can resume devices and safely write
+ * to the swap devices. We disable them again before we leave.
+ *
+ * The second lock_swapdevices() will unlock ignored swap devices since
+ * writing is finished.
+ * 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 int suspend_save_image(void)
+{
+ int error;
+ device_resume();
+ lock_swapdevices();
+ error = write_suspend_image();
+ lock_swapdevices();
+ return error;
+}
+
+/*
+ * Magic happens here
+ */
+
+int swsusp_resume(void)
+{
+ BUG_ON (nr_copy_pages_check != nr_copy_pages);
+ BUG_ON (pagedir_order_check != pagedir_order);
+
+ /* Even mappings of "global" things (vmalloc) need to be fixed */
+ __flush_tlb_global();
+ return 0;
+}
+
+/* swsusp_arch_suspend() is implemented in arch/?/power/swsusp.S,
+ and basically does:
+
+ if (!resume) {
+ save_processor_state();
+ SAVE_REGISTERS
+ return swsusp_suspend();
+ }
+ GO_TO_SWAPPER_PAGE_TABLES
+ COPY_PAGES_BACK
+ RESTORE_REGISTERS
+ restore_processor_state();
+ return swsusp_resume();
+
+ */
+
+
+/* More restore stuff */
+
+/* FIXME: Why not memcpy(to, from, 1<<pagedir_order*PAGE_SIZE)? */
+static void __init copy_pagedir(suspend_pagedir_t *to, suspend_pagedir_t *from)
+{
+ int i;
+ char *topointer=(char *)to, *frompointer=(char *)from;
+
+ for(i=0; i < 1 << pagedir_order; i++) {
+ copy_page(topointer, frompointer);
+ topointer += PAGE_SIZE;
+ frompointer += PAGE_SIZE;
+ }
+}
+
+#define does_collide(addr) does_collide_order(pagedir_nosave, addr, 0)
+
+/*
+ * Returns true if given address/order collides with any orig_address
+ */
+static int __init 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;
+}
+
+/*
+ * 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 __init check_pagedir(void)
+{
+ int i;
+
+ for(i=0; i < nr_copy_pages; i++) {
+ unsigned long addr;
+
+ do {
+ addr = get_zeroed_page(GFP_ATOMIC);
+ if(!addr)
+ return -ENOMEM;
+ } while (does_collide(addr));
+
+ (pagedir_nosave+i)->address = addr;
+ }
+ return 0;
+}
+
+static int __init 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 __init sanity_check_failed(char *reason)
+{
+ printk(KERN_ERR "%s%s\n",name_resume,reason);
+ return -EPERM;
+}
+
+static int __init 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 struct block_device * resume_bdev;
+
+
+/**
+ * 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 void start_io(void)
+{
+ atomic_set(&io_done,1);
+}
+
+static int end_io(struct bio * bio, unsigned int num, int err)
+{
+ atomic_set(&io_done,0);
+ return 0;
+}
+
+static void wait_io(void)
+{
+ blk_run_queues();
+ while(atomic_read(&io_done))
+ io_schedule();
+}
+
+
+/**
+ * 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("ERROR: adding page to bio at %ld\n",page_off);
+ error = -EFAULT;
+ goto Done;
+ }
+
+ if (rw == WRITE)
+ bio_set_pages_dirty(bio);
+ start_io();
+ submit_bio(rw,bio);
+ wait_io();
+ Done:
+ bio_put(bio);
+ return error;
+}
+
+static int
+read_page(pgoff_t page_off, void * page)
+{
+ return submit(READ,page_off,page);
+}
+
+static int
+write_page(pgoff_t page_off, void * page)
+{
+ return submit(WRITE,page_off,page);
+}
+
+
+extern dev_t __init name_to_dev_t(const char *line);
+
+
+#define next_entry(diskpage) diskpage->link.next
+
+static int __init read_suspend_image(void)
+{
+ swp_entry_t next;
+ int i, nr_pgdir_pages;
+ union diskpage *cur;
+ int error = 0;
+
+ cur = (union diskpage *)get_zeroed_page(GFP_ATOMIC);
+ if (!cur)
+ return -ENOMEM;
+
+ if ((error = read_page(0, cur)))
+ goto Done;
+
+ /*
+ * We have to read next position before we overwrite it
+ */
+ next = next_entry(cur);
+
+ 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 ((!memcmp("SWAP-SPACE",cur->swh.magic.magic,10)) ||
+ (!memcmp("SWAPSPACE2",cur->swh.magic.magic,10))) {
+ printk(KERN_ERR "swsusp: Partition is normal swap space\n");
+ error = -EINVAL;
+ goto Done;
+ } else {
+ printk(KERN_ERR "swsusp: Invalid partition type.\n");
+ error = -EINVAL;
+ goto Done;
+ }
+
+ /*
+ * Reset swap signature now.
+ */
+ if ((error = write_page(0,cur)))
+ goto Done;
+
+ printk( "%sSignature found, resuming\n", name_resume );
+ MDELAY(1000);
+
+ if ((error = read_page(swp_offset(next), cur)))
+ goto Done;
+ /* Is this same machine? */
+ if ((error = sanity_check(&cur->sh)))
+ goto Done;
+ next = next_entry(cur);
+
+ 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) {
+ error = -ENOMEM;
+ goto Done;
+ }
+
+ 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;
+ error = read_page(swp_offset(next), cur);
+ if (error)
+ goto FreePagedir;
+ next = next_entry(cur);
+ }
+ BUG_ON (next.val);
+
+ if ((error = relocate_pagedir()))
+ goto FreePagedir;
+ if ((error = check_pagedir()))
+ goto FreePagedir;
+
+ 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 */
+ error = read_page(swp_offset(swap_address),
+ (char *)((pagedir_nosave+i)->address));
+ if (error)
+ goto FreePagedir;
+ }
+ printk( "|\n" );
+ Done:
+ free_page((unsigned long)cur);
+ return error;
+ FreePagedir:
+ free_pages((unsigned long)pagedir_nosave,pagedir_order);
+ goto Done;
+}
+
+/**
+ * swsusp_save - Snapshot memory
+ */
+
+int swsusp_save(void)
+{
+ int error;
+
+#if defined (CONFIG_HIGHMEM) || defined (COFNIG_DISCONTIGMEM)
+ printk("swsusp is not supported with high- or discontig-mem.\n");
+ return -EPERM;
+#endif
+ if ((error = arch_prepare_suspend()))
+ return error;
+ local_irq_disable();
+ error = swsusp_arch_suspend(0);
+ local_irq_enable();
+ return error;
+}
+
+
+/**
+ * swsusp_write - Write saved memory image to swap.
+ *
+ * swsusp_arch_suspend(0) returns after system is resumed.
+ *
+ * swsusp_arch_suspend() copies all "used" memory to "free" memory,
+ * then unsuspends all device drivers, and writes memory to disk
+ * using normal kernel mechanism.
+ */
+
+int swsusp_write(void)
+{
+ return suspend_save_image();
+}
+
+
+/**
+ * swsusp_read - Read saved image from swap.
+ */
+
+int __init swsusp_read(void)
+{
+ int error;
+ char b[BDEVNAME_SIZE];
+
+ if (!strlen(resume_file))
+ return -ENOENT;
+
+ resume_device = name_to_dev_t(resume_file);
+ printk("swsusp: Resume From Partition: %s, Device: %s\n",
+ resume_file, __bdevname(resume_device, b));
+
+ resume_bdev = open_by_devnum(resume_device, FMODE_READ, BDEV_RAW);
+ if (!IS_ERR(resume_bdev)) {
+ set_blocksize(resume_bdev, PAGE_SIZE);
+ error = read_suspend_image();
+ blkdev_put(resume_bdev, BDEV_RAW);
+ } else
+ error = PTR_ERR(resume_bdev);
+
+ if (!error)
+ PRINTK("Reading resume file was successful\n");
+ else
+ printk( "%sError %d resuming\n", name_resume, error );
+ MDELAY(1000);
+ return error;
+}
+
+
+/**
+ * swsusp_restore - Replace running kernel with saved image.
+ */
+
+int __init swsusp_restore(void)
+{
+ int error;
+ local_irq_disable();
+ error = swsusp_arch_suspend(1);
+ local_irq_enable();
+ return error;
+}
+
+
+/**
+ * swsusp_free - Free memory allocated to hold snapshot.
+ */
+
+int swsusp_free(void)
+{
+ PRINTK( "Freeing prev allocated pagedir\n" );
+ free_suspend_pagedir((unsigned long) pagedir_save);
+ return 0;
+}
+
+
+int software_suspend(void)
+{
+ struct pm_ops swsusp_ops = {
+ .pm_disk_mode = PM_DISK_SHUTDOWN,
+ };
+
+ pm_set_ops(&swsusp_ops);
+ return pm_suspend(PM_SUSPEND_DISK);
+}
+
+static int __init resume_setup(char *str)
+{
+ if (strlen(str))
+ strncpy(resume_file, str, 255);
+ return 1;
+}
+
+static int __init noresume_setup(char *str)
+{
+ resume_file[0] = '\0';
+ return 1;
+}
+
+__setup("noresume", noresume_setup);
+__setup("resume=", resume_setup);
+
generated by cgit v1.2.3 (git 2.46.0) at 2026-02-02 20:15:19 +0000