[RFC][PATCH 5/6] swsusp: move swap-handling functions to separate file
From: Rafael J. Wysocki
Date: Sat Oct 29 2005 - 15:55:34 EST
This patch is to show that the swap-handling part of swsusp is really independent
and it can be moved entirely to a separate file. It introduces the file swap.c
containing all of the swap-handling code.
After the change swsusp.c contains the functions that in my opinion do not
belong to either the snapshot-handling part or the swap-handling part
(swsusp_suspend(), swsusp_resume() and the functions related to highmem).
Signed-off-by: Rafael J. Wysocki <rjw@xxxxxxx>
kernel/power/Makefile | 2
kernel/power/power.h | 2
kernel/power/snapshot.c | 93 ----
kernel/power/swap.c | 915 +++++++++++++++++++++++++++++++++++++++++++++++
kernel/power/swsusp.c | 923 +++---------------------------------------------
5 files changed, 988 insertions(+), 947 deletions(-)
Index: linux-2.6.14-rc5-mm1/kernel/power/Makefile
===================================================================
--- linux-2.6.14-rc5-mm1.orig/kernel/power/Makefile 2005-10-29 13:23:31.000000000 +0200
+++ linux-2.6.14-rc5-mm1/kernel/power/Makefile 2005-10-29 13:26:26.000000000 +0200
@@ -4,7 +4,7 @@
endif
obj-y := main.o process.o console.o pm.o
-obj-$(CONFIG_SOFTWARE_SUSPEND) += swsusp.o disk.o snapshot.o
+obj-$(CONFIG_SOFTWARE_SUSPEND) += swsusp.o disk.o snapshot.o swap.o
obj-$(CONFIG_SUSPEND_SMP) += smp.o
Index: linux-2.6.14-rc5-mm1/kernel/power/power.h
===================================================================
--- linux-2.6.14-rc5-mm1.orig/kernel/power/power.h 2005-10-29 13:24:58.000000000 +0200
+++ linux-2.6.14-rc5-mm1/kernel/power/power.h 2005-10-29 13:26:26.000000000 +0200
@@ -58,8 +58,6 @@
extern asmlinkage int swsusp_arch_suspend(void);
extern asmlinkage int swsusp_arch_resume(void);
-extern int save_highmem(void);
-extern int restore_highmem(void);
extern void swsusp_free(void);
extern unsigned snapshot_pages_to_save(void);
Index: linux-2.6.14-rc5-mm1/kernel/power/swap.c
===================================================================
--- /dev/null 1970-01-01 00:00:00.000000000 +0000
+++ linux-2.6.14-rc5-mm1/kernel/power/swap.c 2005-10-29 13:26:26.000000000 +0200
@@ -0,0 +1,915 @@
+/*
+ * linux/kernel/power/snapshot.c
+ *
+ * This file provides the swap writing/reading functionality.
+ *
+ * Copyright (C) 1998-2005 Pavel Machek <pavel@xxxxxxx>
+ * Copyright (C) 2005 Rafael J. Wysocki <rjw@xxxxxxx>
+ *
+ * This file is released under the GPLv2, and is based on swsusp.c.
+ *
+ */
+
+#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/bitops.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/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 <linux/random.h>
+#include <linux/crypto.h>
+#include <asm/scatterlist.h>
+
+#include "power.h"
+
+#define CIPHER "aes"
+#define MAXKEY 32
+#define MAXIV 32
+
+extern char resume_file[];
+
+
+#define SWSUSP_SIG "S1SUSPEND"
+
+static struct swsusp_header {
+ char reserved[PAGE_SIZE - 20 - MAXKEY - MAXIV - sizeof(swp_entry_t)];
+ u8 key_iv[MAXKEY+MAXIV];
+ 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;
+
+/*
+ * 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 write_page(unsigned long addr, swp_entry_t * loc);
+static int bio_read_page(pgoff_t page_off, void * page);
+
+static u8 key_iv[MAXKEY+MAXIV];
+
+#ifdef CONFIG_SWSUSP_ENCRYPT
+
+static int crypto_init(int mode, void **mem)
+{
+ int error = 0;
+ int len;
+ char *modemsg;
+ struct crypto_tfm *tfm;
+
+ modemsg = mode ? "suspend not possible" : "resume not possible";
+
+ tfm = crypto_alloc_tfm(CIPHER, CRYPTO_TFM_MODE_CBC);
+ if(!tfm) {
+ printk(KERN_ERR "swsusp: no tfm, %s\n", modemsg);
+ error = -EINVAL;
+ goto out;
+ }
+
+ if(MAXKEY < crypto_tfm_alg_min_keysize(tfm)) {
+ printk(KERN_ERR "swsusp: key buffer too small, %s\n", modemsg);
+ error = -ENOKEY;
+ goto fail;
+ }
+
+ if (mode)
+ get_random_bytes(key_iv, MAXKEY+MAXIV);
+
+ len = crypto_tfm_alg_max_keysize(tfm);
+ if (len > MAXKEY)
+ len = MAXKEY;
+
+ if (crypto_cipher_setkey(tfm, key_iv, len)) {
+ printk(KERN_ERR "swsusp: key setup failure, %s\n", modemsg);
+ error = -EKEYREJECTED;
+ goto fail;
+ }
+
+ len = crypto_tfm_alg_ivsize(tfm);
+
+ if (MAXIV < len) {
+ printk(KERN_ERR "swsusp: iv buffer too small, %s\n", modemsg);
+ error = -EOVERFLOW;
+ goto fail;
+ }
+
+ crypto_cipher_set_iv(tfm, key_iv+MAXKEY, len);
+
+ *mem=(void *)tfm;
+
+ goto out;
+
+fail: crypto_free_tfm(tfm);
+out: return error;
+}
+
+static __inline__ void crypto_exit(void *mem)
+{
+ crypto_free_tfm((struct crypto_tfm *)mem);
+}
+
+static __inline__ int crypto_write(unsigned long addr, swp_entry_t *entry, void *mem)
+{
+ int error = 0;
+ struct scatterlist src, dst;
+
+ src.page = virt_to_page((void *)addr);
+ src.offset = 0;
+ src.length = PAGE_SIZE;
+ dst.page = virt_to_page((void *)&swsusp_header);
+ dst.offset = 0;
+ dst.length = PAGE_SIZE;
+
+ error = crypto_cipher_encrypt((struct crypto_tfm *)mem, &dst, &src,
+ PAGE_SIZE);
+
+ if (!error)
+ error = write_page((unsigned long)&swsusp_header, entry);
+ return error;
+}
+
+static __inline__ int crypto_read(unsigned long offset, void *buf, void *mem)
+{
+ int error = 0;
+ struct scatterlist src, dst;
+
+ error = bio_read_page(offset, buf);
+ if (!error) {
+ src.offset = 0;
+ src.length = PAGE_SIZE;
+ dst.offset = 0;
+ dst.length = PAGE_SIZE;
+ src.page = dst.page = virt_to_page(buf);
+
+ error = crypto_cipher_decrypt((struct crypto_tfm *)mem, &dst,
+ &src, PAGE_SIZE);
+ }
+ return error;
+}
+#else
+static __inline__ int crypto_init(int mode, void *mem)
+{
+ return 0;
+}
+
+static __inline__ void crypto_exit(void *mem)
+{
+}
+
+static __inline__ int crypto_write(unsigned long addr, swp_entry_t *entry, void *mem)
+{
+ return write_page(addr, entry);
+}
+
+static __inline__ int crypto_read(unsigned long offset, void *buf, void *mem)
+{
+ return bio_read_page(offset, buf);
+}
+#endif
+
+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);
+ memcpy(swsusp_header.key_iv, key_iv, MAXKEY+MAXIV);
+ 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;
+
+ spin_lock(&swap_lock);
+ for (i=0; i<MAX_SWAPFILES; i++) {
+ if (!(swap_info[i].flags & SWP_WRITEOK)) {
+ 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;
+ }
+ }
+ }
+ }
+ spin_unlock(&swap_lock);
+ 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;
+
+ spin_lock(&swap_lock);
+ for (i = 0; i< MAX_SWAPFILES; i++)
+ if (swapfile_used[i] == SWAPFILE_IGNORED) {
+ swap_info[i].flags ^= SWP_WRITEOK;
+ }
+ spin_unlock(&swap_lock);
+}
+
+/**
+ * write_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;
+}
+
+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: Total: %ld Pages\n", swsusp_info.pages);
+}
+
+static void init_header(unsigned nr_pages, unsigned img_pages)
+{
+ 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.cpus = num_online_cpus();
+ swsusp_info.image_pages = img_pages;
+ swsusp_info.pages = nr_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;
+}
+
+/**
+ * Swap map handling functions
+ *
+ * The swap map is a data structure used for keeping track of each page
+ * written to the swap. It consists of many swp_map_page structures
+ * that contain each an array of MAP_PAGE_SIZE swap entries.
+ * These structures are linked together with the help of either the
+ * .next (in memory) or the .next_swp (in swap) member.
+ *
+ * The swap map is created during suspend. At that time we need to keep
+ * it in memory, because we have to free all of the allocated swap
+ * entries if an error occurs. The memory needed is preallocated
+ * so that we know in advance if there's enough of it.
+ *
+ * The first swp_map_page structure is filled with the swap entries that
+ * correspond to the first MAP_PAGE_SIZE data pages written to swap and
+ * so on. After the all of the data pages have been written, the order
+ * of the swp_map_page structures in the map is reversed so that they
+ * can be read from swap in the original order. This causes the data
+ * pages to be loaded in exactly the same order in which they have been
+ * saved.
+ *
+ * During resume we only need to use one swp_map_page structure
+ * at a time, which means that we only need to use two memory pages for
+ * reading the image - one for reading the swp_map_page structures
+ * and the second for reading the data pages from swap.
+ */
+
+#define MAP_PAGE_SIZE ((PAGE_SIZE - sizeof(swp_entry_t) - sizeof(void *)) \
+ / sizeof(swp_entry_t))
+
+struct swp_map_page {
+ swp_entry_t entries[MAP_PAGE_SIZE];
+ swp_entry_t next_swp;
+ struct swp_map_page *next;
+};
+
+typedef struct swp_map_page swp_map_t;
+
+static inline void free_swp_map(swp_map_t *swp_map)
+{
+ swp_map_t *swp;
+
+ while (swp_map) {
+ swp = swp_map->next;
+ free_page((unsigned long)swp_map);
+ swp_map = swp;
+ }
+}
+
+static swp_map_t *alloc_swp_map(unsigned nr_pages)
+{
+ swp_map_t *swp_map, *swp;
+ unsigned n = 0;
+
+ if (!nr_pages)
+ return NULL;
+
+ pr_debug("alloc_swp_map(): nr_pages = %d\n", nr_pages);
+ swp_map = (swp_map_t *)get_zeroed_page(GFP_ATOMIC);
+ swp = swp_map;
+ for (n = MAP_PAGE_SIZE; n < nr_pages; n += MAP_PAGE_SIZE) {
+ swp->next = (swp_map_t *)get_zeroed_page(GFP_ATOMIC);
+ swp = swp->next;
+ if (!swp) {
+ free_swp_map(swp_map);
+ return NULL;
+ }
+ }
+ return swp_map;
+}
+
+static inline swp_map_t *reverse_swp_map(swp_map_t *swp_map)
+{
+ swp_map_t *prev, *next;
+
+ prev = NULL;
+ while (swp_map) {
+ next = swp_map->next;
+ swp_map->next = prev;
+ prev = swp_map;
+ swp_map = next;
+ }
+ return prev;
+}
+
+/**
+ * save_swp_map - save the swap map used for tracing the data pages
+ * stored in swap
+ */
+
+static int save_swp_map(swp_map_t *swp_map, swp_entry_t *start)
+{
+ swp_entry_t entry = (swp_entry_t){0};
+ int error;
+
+ while (swp_map) {
+ swp_map->next_swp = entry;
+ if ((error = write_page((unsigned long)swp_map, &entry)))
+ return error;
+ swp_map = swp_map->next;
+ }
+ *start = entry;
+ return 0;
+}
+
+static inline void free_swp_map_entries(swp_map_t *swp_map)
+{
+ while (swp_map) {
+ if (swp_map->next_swp.val)
+ swap_free(swp_map->next_swp);
+ swp_map = swp_map->next;
+ }
+}
+
+/**
+ * save_image - save the image data provided by the snapshot-handling
+ * part to swap. The swap map is used for keeping track of the
+ * saved pages
+ */
+
+static int save_image(swp_map_t *swp, unsigned nr_pages, void *buf)
+{
+ unsigned n, k;
+ int error;
+ unsigned mod = nr_pages / 100;
+ void *tfm;
+
+ if ((error = crypto_init(1, &tfm)))
+ return error;
+ printk("Writing data to swap (%d pages) ... ", nr_pages);
+ n = 0;
+ while (swp) {
+ for (k = 0; k < MAP_PAGE_SIZE && n < nr_pages; k++, n++) {
+ error = snapshot_send_page(buf);
+ if (!error)
+ error = crypto_write((unsigned long)buf,
+ swp->entries + k, tfm);
+ if (error) {
+ crypto_exit(tfm);
+ return error;
+ }
+ if (!(n % mod))
+ printk("\b\b\b\b%3d%%", n / mod);
+ }
+ swp = swp->next;
+ }
+ printk("\b\b\b\bdone\n");
+ crypto_exit(tfm);
+ return 0;
+}
+
+static inline void free_pages_entries(swp_map_t *swp)
+{
+ unsigned k;
+
+ while (swp) {
+ for (k = 0; k < MAP_PAGE_SIZE; k++)
+ if (swp->entries[k].val)
+ swap_free(swp->entries[k]);
+ swp = swp->next;
+ }
+}
+
+/**
+ * enough_swap - Make sure we have enough swap to save the image.
+ *
+ * Returns TRUE or FALSE after checking the total amount of swap
+ * space avaiable.
+ *
+ * FIXME: si_swapinfo(&i) returns all swap devices information.
+ * We should only consider resume_device.
+ */
+
+static int enough_swap(unsigned long nr_pages)
+{
+ struct sysinfo i;
+
+ si_swapinfo(&i);
+ pr_debug("swsusp: available swap: %lu pages\n", i.freeswap);
+ return i.freeswap > (nr_pages + PAGES_FOR_IO +
+ (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE);
+}
+
+/**
+ * write_suspend_image - Write entire image and metadata.
+ *
+ */
+static int write_suspend_image(void)
+{
+ unsigned nr_pages;
+ int error;
+ swp_map_t *swp_map;
+ void *buffer;
+
+ nr_pages = snapshot_pages_to_save();
+ if (!enough_swap(nr_pages)) {
+ printk(KERN_ERR "swsusp: Not enough free swap\n");
+ return -ENOSPC;
+ }
+
+ init_header(nr_pages, snapshot_image_pages());
+ buffer = (void *)get_zeroed_page(GFP_ATOMIC);
+ if (!buffer)
+ return -ENOMEM;
+
+ swp_map = alloc_swp_map(nr_pages);
+ if (!swp_map) {
+ free_page((unsigned long)buffer);
+ return -ENOMEM;
+ }
+ snapshot_send_init();
+ if ((error = save_image(swp_map, nr_pages, buffer)))
+ goto Free_pages_entries;
+ if ((error = snapshot_finish()))
+ goto Free_pages_entries;
+ swp_map = reverse_swp_map(swp_map);
+ if ((error = save_swp_map(swp_map, &swsusp_info.start)))
+ goto Free_map_entries;
+ if ((error = close_swap()))
+ goto Free_map_entries;
+
+Free_mem:
+ free_swp_map(swp_map);
+ free_page((unsigned long)buffer);
+ memset(key_iv, 0, MAXKEY+MAXIV);
+ return error;
+
+Free_map_entries:
+ free_swp_map_entries(swp_map);
+Free_pages_entries:
+ free_pages_entries(swp_map);
+ goto Free_mem;
+}
+
+/* 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;
+
+ if ((error = swsusp_swap_check())) {
+ printk(KERN_ERR "swsusp: cannot find swap device, try swapon -a.\n");
+ return error;
+ }
+ lock_swapdevices();
+ error = write_suspend_image();
+ /* This will unlock ignored swap devices since writing is finished */
+ lock_swapdevices();
+ return error;
+}
+
+/**
+ * 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);
+}
+
+/**
+ * load_image - Load the image and metadata from swap, using the
+ * snapshot_recv_page() function provided by the snapshot-handling code
+ *
+ * We assume that the data has been saved using the swap map handling
+ * functions above
+ */
+static int load_image(unsigned nr_pages, swp_entry_t start)
+{
+ swp_map_t *swp;
+ void *buf;
+ unsigned n, k;
+ unsigned long offset = swp_offset(start);
+ int error;
+ unsigned mod = nr_pages / 100;
+ void *tfm;
+
+ if (!nr_pages || !offset)
+ return -EINVAL;
+
+ if ((error = crypto_init(0, &tfm)))
+ return error;
+
+ buf = (void *)get_zeroed_page(GFP_ATOMIC);
+ if (!buf) {
+ error = -ENOMEM;
+ goto Crypto_exit;
+ }
+ swp = (swp_map_t *)get_zeroed_page(GFP_ATOMIC);
+ if (!swp) {
+ error = -ENOMEM;
+ goto Free_buf;
+ }
+ printk("Loading data from swap (%d pages) ... ", nr_pages);
+ n = 0;
+ while (n < nr_pages) {
+ if ((error = crypto_read(offset, (void *)swp, tfm)))
+ goto Free;
+ for (k = 0; k < MAP_PAGE_SIZE && n < nr_pages; k++, n++) {
+ error = bio_read_page(swp_offset(swp->entries[k]), buf);
+ if (!error)
+ error = snapshot_recv_page(buf);
+ if (error)
+ goto Free;
+ if (!(n % mod))
+ printk("\b\b\b\b%3d%%", n / mod);
+ }
+ offset = swp_offset(swp->next_swp);
+ }
+ printk("\b\b\b\bdone\n");
+Free:
+ free_page((unsigned long)swp);
+Free_buf:
+ free_page((unsigned long)buf);
+Crypto_exit:
+ crypto_exit(tfm);
+ return error;
+}
+
+/*
+ * 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 0
+ /* We can't use number of online CPUs when we use hotplug to remove them ;-))) */
+ if (swsusp_info.cpus != num_possible_cpus())
+ return "number of cpus";
+#endif
+ 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;
+ }
+ 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);
+ memcpy(key_iv, swsusp_header.key_iv, MAXKEY+MAXIV);
+ memset(swsusp_header.key_iv, 0, MAXKEY+MAXIV);
+
+ /*
+ * Reset swap signature now.
+ */
+ error = bio_write_page(0, &swsusp_header);
+ } else {
+ return -EINVAL;
+ }
+ if (!error)
+ pr_debug("swsusp: Signature found, resuming\n");
+ 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;
+
+ error = snapshot_recv_init(swsusp_info.pages, swsusp_info.image_pages);
+ if (!error)
+ error = load_image(swsusp_info.pages, swsusp_info.start);
+ if (!error)
+ error = snapshot_finish();
+ return error;
+}
+
+/**
+ * swsusp_check - Check for saved image in swap
+ */
+
+int swsusp_check(void)
+{
+ int error;
+
+ 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);
+ memset(key_iv, 0, MAXKEY+MAXIV);
+
+ 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);
+}
+
Index: linux-2.6.14-rc5-mm1/kernel/power/snapshot.c
===================================================================
--- linux-2.6.14-rc5-mm1.orig/kernel/power/snapshot.c 2005-10-29 13:24:58.000000000 +0200
+++ linux-2.6.14-rc5-mm1/kernel/power/snapshot.c 2005-10-29 13:26:26.000000000 +0200
@@ -39,99 +39,6 @@
static unsigned nr_copy_pages;
static unsigned nr_pb_pages;
-#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;
-}
-
-
-int save_highmem(void)
-{
- 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;
- }
- return 0;
-}
-
-int restore_highmem(void)
-{
- 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);
- }
- return 0;
-}
-#else
-int save_highmem(void) { return 0; }
-int restore_highmem(void) { return 0; }
-#endif /* CONFIG_HIGHMEM */
-
-
static int pfn_is_nosave(unsigned long pfn)
{
unsigned long nosave_begin_pfn = __pa(&__nosave_begin) >> PAGE_SHIFT;
Index: linux-2.6.14-rc5-mm1/kernel/power/swsusp.c
===================================================================
--- linux-2.6.14-rc5-mm1.orig/kernel/power/swsusp.c 2005-10-29 13:25:41.000000000 +0200
+++ linux-2.6.14-rc5-mm1/kernel/power/swsusp.c 2005-10-29 13:26:26.000000000 +0200
@@ -76,586 +76,96 @@
#include "power.h"
-#define CIPHER "aes"
-#define MAXKEY 32
-#define MAXIV 32
-
-extern char resume_file[];
-
-
-#define SWSUSP_SIG "S1SUSPEND"
-
-static struct swsusp_header {
- char reserved[PAGE_SIZE - 20 - MAXKEY - MAXIV - sizeof(swp_entry_t)];
- u8 key_iv[MAXKEY+MAXIV];
- 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;
-
-/*
- * 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 write_page(unsigned long addr, swp_entry_t * loc);
-static int bio_read_page(pgoff_t page_off, void * page);
-
-static u8 key_iv[MAXKEY+MAXIV];
-
-#ifdef CONFIG_SWSUSP_ENCRYPT
-
-static int crypto_init(int mode, void **mem)
-{
- int error = 0;
- int len;
- char *modemsg;
- struct crypto_tfm *tfm;
-
- modemsg = mode ? "suspend not possible" : "resume not possible";
-
- tfm = crypto_alloc_tfm(CIPHER, CRYPTO_TFM_MODE_CBC);
- if(!tfm) {
- printk(KERN_ERR "swsusp: no tfm, %s\n", modemsg);
- error = -EINVAL;
- goto out;
- }
-
- if(MAXKEY < crypto_tfm_alg_min_keysize(tfm)) {
- printk(KERN_ERR "swsusp: key buffer too small, %s\n", modemsg);
- error = -ENOKEY;
- goto fail;
- }
-
- if (mode)
- get_random_bytes(key_iv, MAXKEY+MAXIV);
-
- len = crypto_tfm_alg_max_keysize(tfm);
- if (len > MAXKEY)
- len = MAXKEY;
-
- if (crypto_cipher_setkey(tfm, key_iv, len)) {
- printk(KERN_ERR "swsusp: key setup failure, %s\n", modemsg);
- error = -EKEYREJECTED;
- goto fail;
- }
-
- len = crypto_tfm_alg_ivsize(tfm);
-
- if (MAXIV < len) {
- printk(KERN_ERR "swsusp: iv buffer too small, %s\n", modemsg);
- error = -EOVERFLOW;
- goto fail;
- }
-
- crypto_cipher_set_iv(tfm, key_iv+MAXKEY, len);
-
- *mem=(void *)tfm;
-
- goto out;
-
-fail: crypto_free_tfm(tfm);
-out: return error;
-}
-
-static __inline__ void crypto_exit(void *mem)
-{
- crypto_free_tfm((struct crypto_tfm *)mem);
-}
-
-static __inline__ int crypto_write(unsigned long addr, swp_entry_t *entry, void *mem)
-{
- int error = 0;
- struct scatterlist src, dst;
-
- src.page = virt_to_page((void *)addr);
- src.offset = 0;
- src.length = PAGE_SIZE;
- dst.page = virt_to_page((void *)&swsusp_header);
- dst.offset = 0;
- dst.length = PAGE_SIZE;
-
- error = crypto_cipher_encrypt((struct crypto_tfm *)mem, &dst, &src,
- PAGE_SIZE);
-
- if (!error)
- error = write_page((unsigned long)&swsusp_header, entry);
- return error;
-}
-
-static __inline__ int crypto_read(unsigned long offset, void *buf, void *mem)
-{
- int error = 0;
- struct scatterlist src, dst;
-
- error = bio_read_page(offset, buf);
- if (!error) {
- src.offset = 0;
- src.length = PAGE_SIZE;
- dst.offset = 0;
- dst.length = PAGE_SIZE;
- src.page = dst.page = virt_to_page(buf);
-
- error = crypto_cipher_decrypt((struct crypto_tfm *)mem, &dst,
- &src, PAGE_SIZE);
- }
- return error;
-}
-#else
-static __inline__ int crypto_init(int mode, void *mem)
-{
- return 0;
-}
-
-static __inline__ void crypto_exit(void *mem)
-{
-}
-
-static __inline__ int crypto_write(unsigned long addr, swp_entry_t *entry, void *mem)
-{
- return write_page(addr, entry);
-}
-
-static __inline__ int crypto_read(unsigned long offset, void *buf, void *mem)
-{
- return bio_read_page(offset, buf);
-}
-#endif
-
-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);
- memcpy(swsusp_header.key_iv, key_iv, MAXKEY+MAXIV);
- 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;
-
- spin_lock(&swap_lock);
- for (i=0; i<MAX_SWAPFILES; i++) {
- if (!(swap_info[i].flags & SWP_WRITEOK)) {
- 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;
- }
- }
- }
- }
- spin_unlock(&swap_lock);
- 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;
-
- spin_lock(&swap_lock);
- for (i = 0; i< MAX_SWAPFILES; i++)
- if (swapfile_used[i] == SWAPFILE_IGNORED) {
- swap_info[i].flags ^= SWP_WRITEOK;
- }
- spin_unlock(&swap_lock);
-}
-
-/**
- * write_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;
-}
-
-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: Total: %ld Pages\n", swsusp_info.pages);
-}
-
-static void init_header(unsigned nr_pages, unsigned img_pages)
-{
- 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.cpus = num_online_cpus();
- swsusp_info.image_pages = img_pages;
- swsusp_info.pages = nr_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;
-}
-
-/**
- * Swap map handling functions
- *
- * The swap map is a data structure used for keeping track of each page
- * written to the swap. It consists of many swp_map_page structures
- * that contain each an array of MAP_PAGE_SIZE swap entries.
- * These structures are linked together with the help of either the
- * .next (in memory) or the .next_swp (in swap) member.
- *
- * The swap map is created during suspend. At that time we need to keep
- * it in memory, because we have to free all of the allocated swap
- * entries if an error occurs. The memory needed is preallocated
- * so that we know in advance if there's enough of it.
- *
- * The first swp_map_page structure is filled with the swap entries that
- * correspond to the first MAP_PAGE_SIZE data pages written to swap and
- * so on. After the all of the data pages have been written, the order
- * of the swp_map_page structures in the map is reversed so that they
- * can be read from swap in the original order. This causes the data
- * pages to be loaded in exactly the same order in which they have been
- * saved.
- *
- * During resume we only need to use one swp_map_page structure
- * at a time, which means that we only need to use two memory pages for
- * reading the image - one for reading the swp_map_page structures
- * and the second for reading the data pages from swap.
- */
-
-#define MAP_PAGE_SIZE ((PAGE_SIZE - sizeof(swp_entry_t) - sizeof(void *)) \
- / sizeof(swp_entry_t))
-
-struct swp_map_page {
- swp_entry_t entries[MAP_PAGE_SIZE];
- swp_entry_t next_swp;
- struct swp_map_page *next;
+#ifdef CONFIG_HIGHMEM
+struct highmem_page {
+ char *data;
+ struct page *page;
+ struct highmem_page *next;
};
-typedef struct swp_map_page swp_map_t;
-
-static inline void free_swp_map(swp_map_t *swp_map)
-{
- swp_map_t *swp;
-
- while (swp_map) {
- swp = swp_map->next;
- free_page((unsigned long)swp_map);
- swp_map = swp;
- }
-}
+static struct highmem_page *highmem_copy;
-static swp_map_t *alloc_swp_map(unsigned nr_pages)
+static int save_highmem_zone(struct zone *zone)
{
- swp_map_t *swp_map, *swp;
- unsigned n = 0;
-
- if (!nr_pages)
- return NULL;
-
- pr_debug("alloc_swp_map(): nr_pages = %d\n", nr_pages);
- swp_map = (swp_map_t *)get_zeroed_page(GFP_ATOMIC);
- swp = swp_map;
- for (n = MAP_PAGE_SIZE; n < nr_pages; n += MAP_PAGE_SIZE) {
- swp->next = (swp_map_t *)get_zeroed_page(GFP_ATOMIC);
- swp = swp->next;
- if (!swp) {
- free_swp_map(swp_map);
- return NULL;
+ 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;
}
- }
- return swp_map;
-}
-
-static inline swp_map_t *reverse_swp_map(swp_map_t *swp_map)
-{
- swp_map_t *prev, *next;
-
- prev = NULL;
- while (swp_map) {
- next = swp_map->next;
- swp_map->next = prev;
- prev = swp_map;
- swp_map = next;
- }
- return prev;
-}
-
-/**
- * save_swp_map - save the swap map used for tracing the data pages
- * stored in swap
- */
-
-static int save_swp_map(swp_map_t *swp_map, swp_entry_t *start)
-{
- swp_entry_t entry = (swp_entry_t){0};
- int error;
-
- while (swp_map) {
- swp_map->next_swp = entry;
- if ((error = write_page((unsigned long)swp_map, &entry)))
- return error;
- swp_map = swp_map->next;
- }
- *start = entry;
- return 0;
-}
-
-static inline void free_swp_map_entries(swp_map_t *swp_map)
-{
- while (swp_map) {
- if (swp_map->next_swp.val)
- swap_free(swp_map->next_swp);
- swp_map = swp_map->next;
- }
-}
-
-/**
- * save_image - save the image data provided by the snapshot-handling
- * part to swap. The swap map is used for keeping track of the
- * saved pages
- */
-
-static int save_image(swp_map_t *swp, unsigned nr_pages, void *buf)
-{
- unsigned n, k;
- int error;
- unsigned mod = nr_pages / 100;
- void *tfm;
-
- if ((error = crypto_init(1, &tfm)))
- return error;
- printk("Writing data to swap (%d pages) ... ", nr_pages);
- n = 0;
- while (swp) {
- for (k = 0; k < MAP_PAGE_SIZE && n < nr_pages; k++, n++) {
- error = snapshot_send_page(buf);
- if (!error)
- error = crypto_write((unsigned long)buf,
- swp->entries + k, tfm);
- if (error) {
- crypto_exit(tfm);
- return error;
- }
- if (!(n % mod))
- printk("\b\b\b\b%3d%%", n / mod);
+ 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;
}
- swp = swp->next;
+ kaddr = kmap_atomic(page, KM_USER0);
+ memcpy(save->data, kaddr, PAGE_SIZE);
+ kunmap_atomic(kaddr, KM_USER0);
+ highmem_copy = save;
}
- printk("\b\b\b\bdone\n");
- crypto_exit(tfm);
return 0;
}
-static inline void free_pages_entries(swp_map_t *swp)
-{
- unsigned k;
-
- while (swp) {
- for (k = 0; k < MAP_PAGE_SIZE; k++)
- if (swp->entries[k].val)
- swap_free(swp->entries[k]);
- swp = swp->next;
- }
-}
-
-/**
- * enough_swap - Make sure we have enough swap to save the image.
- *
- * Returns TRUE or FALSE after checking the total amount of swap
- * space avaiable.
- *
- * FIXME: si_swapinfo(&i) returns all swap devices information.
- * We should only consider resume_device.
- */
-
-static int enough_swap(unsigned long nr_pages)
-{
- struct sysinfo i;
-
- si_swapinfo(&i);
- pr_debug("swsusp: available swap: %lu pages\n", i.freeswap);
- return i.freeswap > (nr_pages + PAGES_FOR_IO +
- (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE);
-}
-
-/**
- * write_suspend_image - Write entire image and metadata.
- *
- */
-static int write_suspend_image(void)
+static int save_highmem(void)
{
- unsigned nr_pages;
- int error;
- swp_map_t *swp_map;
- void *buffer;
+ struct zone *zone;
+ int res = 0;
- nr_pages = snapshot_pages_to_save();
- if (!enough_swap(nr_pages)) {
- printk(KERN_ERR "swsusp: Not enough free swap\n");
- return -ENOSPC;
+ pr_debug("swsusp: Saving Highmem\n");
+ for_each_zone (zone) {
+ if (is_highmem(zone))
+ res = save_highmem_zone(zone);
+ if (res)
+ return res;
}
-
- init_header(nr_pages, snapshot_image_pages());
- buffer = (void *)get_zeroed_page(GFP_ATOMIC);
- if (!buffer)
- return -ENOMEM;
-
- swp_map = alloc_swp_map(nr_pages);
- if (!swp_map) {
- free_page((unsigned long)buffer);
- return -ENOMEM;
- }
- snapshot_send_init();
- if ((error = save_image(swp_map, nr_pages, buffer)))
- goto Free_pages_entries;
- if ((error = snapshot_finish()))
- goto Free_pages_entries;
- swp_map = reverse_swp_map(swp_map);
- if ((error = save_swp_map(swp_map, &swsusp_info.start)))
- goto Free_map_entries;
- if ((error = close_swap()))
- goto Free_map_entries;
-
-Free_mem:
- free_swp_map(swp_map);
- free_page((unsigned long)buffer);
- memset(key_iv, 0, MAXKEY+MAXIV);
- return error;
-
-Free_map_entries:
- free_swp_map_entries(swp_map);
-Free_pages_entries:
- free_pages_entries(swp_map);
- goto Free_mem;
+ 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)
+static int restore_highmem(void)
{
- int error;
-
- if ((error = swsusp_swap_check())) {
- printk(KERN_ERR "swsusp: cannot find swap device, try swapon -a.\n");
- return error;
+ 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);
}
- lock_swapdevices();
- error = write_suspend_image();
- /* This will unlock ignored swap devices since writing is finished */
- lock_swapdevices();
- return error;
+ return 0;
}
-
-
+#else
+static int save_highmem(void) { return 0; }
+static int restore_highmem(void) { return 0; }
+#endif /* CONFIG_HIGHMEM */
int swsusp_suspend(void)
{
@@ -718,292 +228,3 @@
local_irq_enable();
return error;
}
-
-/*
- * 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);
-}
-
-/**
- * load_image - Load the image and metadata from swap, using the
- * snapshot_recv_page() function provided by the snapshot-handling code
- *
- * We assume that the data has been saved using the swap map handling
- * functions above
- */
-static int load_image(unsigned nr_pages, swp_entry_t start)
-{
- swp_map_t *swp;
- void *buf;
- unsigned n, k;
- unsigned long offset = swp_offset(start);
- int error;
- unsigned mod = nr_pages / 100;
- void *tfm;
-
- if (!nr_pages || !offset)
- return -EINVAL;
-
- if ((error = crypto_init(0, &tfm)))
- return error;
-
- buf = (void *)get_zeroed_page(GFP_ATOMIC);
- if (!buf) {
- error = -ENOMEM;
- goto Crypto_exit;
- }
- swp = (swp_map_t *)get_zeroed_page(GFP_ATOMIC);
- if (!swp) {
- error = -ENOMEM;
- goto Free_buf;
- }
- printk("Loading data from swap (%d pages) ... ", nr_pages);
- n = 0;
- while (n < nr_pages) {
- if ((error = crypto_read(offset, (void *)swp, tfm)))
- goto Free;
- for (k = 0; k < MAP_PAGE_SIZE && n < nr_pages; k++, n++) {
- error = bio_read_page(swp_offset(swp->entries[k]), buf);
- if (!error)
- error = snapshot_recv_page(buf);
- if (error)
- goto Free;
- if (!(n % mod))
- printk("\b\b\b\b%3d%%", n / mod);
- }
- offset = swp_offset(swp->next_swp);
- }
- printk("\b\b\b\bdone\n");
-Free:
- free_page((unsigned long)swp);
-Free_buf:
- free_page((unsigned long)buf);
-Crypto_exit:
- crypto_exit(tfm);
- return error;
-}
-
-/*
- * 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 0
- /* We can't use number of online CPUs when we use hotplug to remove them ;-))) */
- if (swsusp_info.cpus != num_possible_cpus())
- return "number of cpus";
-#endif
- 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;
- }
- 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);
- memcpy(key_iv, swsusp_header.key_iv, MAXKEY+MAXIV);
- memset(swsusp_header.key_iv, 0, MAXKEY+MAXIV);
-
- /*
- * Reset swap signature now.
- */
- error = bio_write_page(0, &swsusp_header);
- } else {
- return -EINVAL;
- }
- if (!error)
- pr_debug("swsusp: Signature found, resuming\n");
- 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;
-
- error = snapshot_recv_init(swsusp_info.pages, swsusp_info.image_pages);
- if (!error)
- error = load_image(swsusp_info.pages, swsusp_info.start);
- if (!error)
- error = snapshot_finish();
- return error;
-}
-
-/**
- * swsusp_check - Check for saved image in swap
- */
-
-int swsusp_check(void)
-{
- int error;
-
- 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);
- memset(key_iv, 0, MAXKEY+MAXIV);
-
- 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);
-}
-
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