/*
* 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) 1998,2001-2005 Pavel Machek <pavel@suse.cz>
* Alex Badea <vampire@go.ro>:
* Fixed runaway init
*
- * Andreas Steinmetz <ast@domdv.de>:
- * Added encrypted suspend option
+ * Rafael J. Wysocki <rjw@sisk.pl>
+ * Added the swap map data structure and reworked the handling of swap
*
* More state savers are welcome. Especially for the scsi layer...
*
#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/swapops.h>
#include <linux/bootmem.h>
#include <linux/syscalls.h>
-#include <linux/console.h>
#include <linux/highmem.h>
#include <linux/bio.h>
-#include <linux/mount.h>
#include <asm/uaccess.h>
#include <asm/mmu_context.h>
#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
+#ifdef CONFIG_HIGHMEM
+int save_highmem(void);
+int restore_highmem(void);
+#else
+static int save_highmem(void) { return 0; }
+static int restore_highmem(void) { return 0; }
+#endif
extern char resume_file[];
-/* Local variables that should not be affected by save */
-unsigned int nr_copy_pages __nosavedata = 0;
-
-/* Suspend pagedir is allocated before final copy, therefore it
- must be freed after resume
-
- Warning: this is evil. There are actually two pagedirs at time of
- resume. One is "pagedir_save", which is empty frame allocated at
- time of suspend, that must be freed. Second is "pagedir_nosave",
- allocated at time of resume, that travels through memory not to
- collide with anything.
-
- Warning: this is even more evil than it seems. Pagedirs this file
- talks about are completely different from page directories used by
- MMU hardware.
- */
-suspend_pagedir_t *pagedir_nosave __nosavedata = NULL;
-suspend_pagedir_t *pagedir_save;
-
#define SWSUSP_SIG "S1SUSPEND"
static struct swsusp_header {
- char reserved[PAGE_SIZE - 20 - MAXKEY - MAXIV - sizeof(swp_entry_t)];
- u8 key_iv[MAXKEY+MAXIV];
+ char reserved[PAGE_SIZE - 20 - sizeof(swp_entry_t)];
swp_entry_t swsusp_info;
char orig_sig[10];
char sig[10];
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(struct pbe *p, void *mem)
-{
- int error = 0;
- struct scatterlist src, dst;
-
- src.page = virt_to_page(p->address);
- 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,
- &(p->swap_address));
- return error;
-}
-
-static __inline__ int crypto_read(struct pbe *p, void *mem)
-{
- int error = 0;
- struct scatterlist src, dst;
-
- error = bio_read_page(swp_offset(p->swap_address), (void *)p->address);
- if (!error) {
- src.offset = 0;
- src.length = PAGE_SIZE;
- dst.offset = 0;
- dst.length = PAGE_SIZE;
- src.page = dst.page = virt_to_page((void *)p->address);
-
- 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(struct pbe *p, void *mem)
-{
- return write_page(p->address, &(p->swap_address));
-}
-
-static __inline__ int crypto_read(struct pbe *p, void *mem)
-{
- return bio_read_page(swp_offset(p->swap_address), (void *)p->address);
-}
-#endif
-
static int mark_swapfiles(swp_entry_t prev)
{
int error;
!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),
* 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)
+static int write_page(unsigned long addr, swp_entry_t *loc)
{
swp_entry_t entry;
int error = 0;
}
/**
- * data_free - Free the swap entries used by the saved image.
+ * 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 swap_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_swap (in swap) member.
*
- * Walk the list of used swap entries and free each one.
- * This is only used for cleanup when suspend fails.
+ * 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 swap_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 swap_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 swap_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 swap_map_page structures
+ * and the second for reading the data pages from swap.
*/
-static void data_free(void)
+
+#define MAP_PAGE_SIZE ((PAGE_SIZE - sizeof(swp_entry_t) - sizeof(void *)) \
+ / sizeof(swp_entry_t))
+
+struct swap_map_page {
+ swp_entry_t entries[MAP_PAGE_SIZE];
+ swp_entry_t next_swap;
+ struct swap_map_page *next;
+};
+
+static inline void free_swap_map(struct swap_map_page *swap_map)
{
- swp_entry_t entry;
- struct pbe * p;
+ struct swap_map_page *swp;
- for_each_pbe(p, pagedir_nosave) {
- entry = p->swap_address;
- if (entry.val)
- swap_free(entry);
- else
- break;
+ while (swap_map) {
+ swp = swap_map->next;
+ free_page((unsigned long)swap_map);
+ swap_map = swp;
}
}
+static struct swap_map_page *alloc_swap_map(unsigned int nr_pages)
+{
+ struct swap_map_page *swap_map, *swp;
+ unsigned n = 0;
+
+ if (!nr_pages)
+ return NULL;
+
+ pr_debug("alloc_swap_map(): nr_pages = %d\n", nr_pages);
+ swap_map = (struct swap_map_page *)get_zeroed_page(GFP_ATOMIC);
+ swp = swap_map;
+ for (n = MAP_PAGE_SIZE; n < nr_pages; n += MAP_PAGE_SIZE) {
+ swp->next = (struct swap_map_page *)get_zeroed_page(GFP_ATOMIC);
+ swp = swp->next;
+ if (!swp) {
+ free_swap_map(swap_map);
+ return NULL;
+ }
+ }
+ return swap_map;
+}
+
/**
- * data_write - Write saved image to swap.
- *
- * Walk the list of pages in the image and sync each one to swap.
+ * reverse_swap_map - reverse the order of pages in the swap map
+ * @swap_map
*/
-static int data_write(void)
+
+static inline struct swap_map_page *reverse_swap_map(struct swap_map_page *swap_map)
{
- int error = 0, i = 0;
- unsigned int mod = nr_copy_pages / 100;
- struct pbe *p;
- void *tfm;
+ struct swap_map_page *prev, *next;
+
+ prev = NULL;
+ while (swap_map) {
+ next = swap_map->next;
+ swap_map->next = prev;
+ prev = swap_map;
+ swap_map = next;
+ }
+ return prev;
+}
- if ((error = crypto_init(1, &tfm)))
- return error;
+/**
+ * free_swap_map_entries - free the swap entries allocated to store
+ * the swap map @swap_map (this is only called in case of an error)
+ */
+static inline void free_swap_map_entries(struct swap_map_page *swap_map)
+{
+ while (swap_map) {
+ if (swap_map->next_swap.val)
+ swap_free(swap_map->next_swap);
+ swap_map = swap_map->next;
+ }
+}
- if (!mod)
- mod = 1;
+/**
+ * save_swap_map - save the swap map used for tracing the data pages
+ * stored in the swap
+ */
- printk( "Writing data to swap (%d pages)... ", nr_copy_pages );
- for_each_pbe (p, pagedir_nosave) {
- if (!(i%mod))
- printk( "\b\b\b\b%3d%%", i / mod );
- if ((error = crypto_write(p, tfm))) {
- crypto_exit(tfm);
+static int save_swap_map(struct swap_map_page *swap_map, swp_entry_t *start)
+{
+ swp_entry_t entry = (swp_entry_t){0};
+ int error;
+
+ while (swap_map) {
+ swap_map->next_swap = entry;
+ if ((error = write_page((unsigned long)swap_map, &entry)))
return error;
- }
- i++;
+ swap_map = swap_map->next;
+ }
+ *start = entry;
+ return 0;
+}
+
+/**
+ * free_image_entries - free the swap entries allocated to store
+ * the image data pages (this is only called in case of an error)
+ */
+
+static inline void free_image_entries(struct swap_map_page *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;
}
- printk("\b\b\b\bdone\n");
- crypto_exit(tfm);
+}
+
+/**
+ * The swap_map_handle structure is used for handling the swap map in
+ * a file-alike way
+ */
+
+struct swap_map_handle {
+ struct swap_map_page *cur;
+ unsigned int k;
+};
+
+static inline void init_swap_map_handle(struct swap_map_handle *handle,
+ struct swap_map_page *map)
+{
+ handle->cur = map;
+ handle->k = 0;
+}
+
+static inline int swap_map_write_page(struct swap_map_handle *handle,
+ unsigned long addr)
+{
+ int error;
+
+ error = write_page(addr, handle->cur->entries + handle->k);
+ if (error)
+ return error;
+ if (++handle->k >= MAP_PAGE_SIZE) {
+ handle->cur = handle->cur->next;
+ handle->k = 0;
+ }
+ return 0;
+}
+
+/**
+ * save_image_data - save the data pages pointed to by the PBEs
+ * from the list @pblist using the swap map handle @handle
+ * (assume there are @nr_pages data pages to save)
+ */
+
+static int save_image_data(struct pbe *pblist,
+ struct swap_map_handle *handle,
+ unsigned int nr_pages)
+{
+ unsigned int m;
+ struct pbe *p;
+ int error = 0;
+
+ printk("Saving image data pages (%u pages) ... ", nr_pages);
+ m = nr_pages / 100;
+ if (!m)
+ m = 1;
+ nr_pages = 0;
+ for_each_pbe (p, pblist) {
+ error = swap_map_write_page(handle, p->address);
+ if (error)
+ break;
+ if (!(nr_pages % m))
+ printk("\b\b\b\b%3d%%", nr_pages / m);
+ nr_pages++;
+ }
+ if (!error)
+ printk("\b\b\b\bdone\n");
return error;
}
pr_debug(" swsusp: UTS Domain: %s\n",swsusp_info.uts.domainname);
pr_debug(" swsusp: CPUs: %d\n",swsusp_info.cpus);
pr_debug(" swsusp: Image: %ld Pages\n",swsusp_info.image_pages);
- pr_debug(" swsusp: Pagedir: %ld Pages\n",swsusp_info.pagedir_pages);
+ pr_debug(" swsusp: Total: %ld Pages\n", swsusp_info.pages);
}
-static void init_header(void)
+static void init_header(unsigned int nr_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.suspend_pagedir = pagedir_nosave;
swsusp_info.cpus = num_online_cpus();
- swsusp_info.image_pages = nr_copy_pages;
+ swsusp_info.image_pages = nr_pages;
+ swsusp_info.pages = nr_pages +
+ ((nr_pages * sizeof(long) + PAGE_SIZE - 1) >> PAGE_SHIFT);
}
static int close_swap(void)
}
/**
- * free_pagedir_entries - Free pages used by the page directory.
- *
- * This is used during suspend for error recovery.
+ * pack_orig_addresses - the .orig_address fields of the PBEs from the
+ * list starting at @pbe are stored in the array @buf[] (1 page)
*/
-static void free_pagedir_entries(void)
+static inline struct pbe *pack_orig_addresses(unsigned long *buf,
+ struct pbe *pbe)
{
- int i;
+ int j;
- for (i = 0; i < swsusp_info.pagedir_pages; i++)
- swap_free(swsusp_info.pagedir[i]);
+ for (j = 0; j < PAGE_SIZE / sizeof(long) && pbe; j++) {
+ buf[j] = pbe->orig_address;
+ pbe = pbe->next;
+ }
+ if (!pbe)
+ for (; j < PAGE_SIZE / sizeof(long); j++)
+ buf[j] = 0;
+ return pbe;
}
-
/**
- * write_pagedir - Write the array of pages holding the page directory.
- * @last: Last swap entry we write (needed for header).
+ * save_image_metadata - save the .orig_address fields of the PBEs
+ * from the list @pblist using the swap map handle @handle
*/
-static int write_pagedir(void)
+static int save_image_metadata(struct pbe *pblist,
+ struct swap_map_handle *handle)
{
+ unsigned long *buf;
+ unsigned int n = 0;
+ struct pbe *p;
int error = 0;
- unsigned n = 0;
- struct pbe * pbe;
- printk( "Writing pagedir...");
- for_each_pb_page (pbe, pagedir_nosave) {
- if ((error = write_page((unsigned long)pbe, &swsusp_info.pagedir[n++])))
- return error;
+ printk("Saving image metadata ... ");
+ buf = (unsigned long *)get_zeroed_page(GFP_ATOMIC);
+ if (!buf)
+ return -ENOMEM;
+ p = pblist;
+ while (p) {
+ p = pack_orig_addresses(buf, p);
+ error = swap_map_write_page(handle, (unsigned long)buf);
+ if (error)
+ break;
+ n++;
}
-
- swsusp_info.pagedir_pages = n;
- printk("done (%u pages)\n", n);
- return error;
-}
-
-/**
- * write_suspend_image - Write entire image and metadata.
- *
- */
-static int write_suspend_image(void)
-{
- int error;
-
- init_header();
- if ((error = data_write()))
- goto FreeData;
-
- if ((error = write_pagedir()))
- goto FreePagedir;
-
- if ((error = close_swap()))
- goto FreePagedir;
- Done:
- memset(key_iv, 0, MAXKEY+MAXIV);
+ free_page((unsigned long)buf);
+ if (!error)
+ printk("done (%u pages saved)\n", n);
return error;
- FreePagedir:
- free_pagedir_entries();
- FreeData:
- data_free();
- goto Done;
}
/**
* We should only consider resume_device.
*/
-int enough_swap(void)
+static int enough_swap(unsigned int nr_pages)
{
struct sysinfo i;
si_swapinfo(&i);
pr_debug("swsusp: available swap: %lu pages\n", i.freeswap);
- return i.freeswap > (nr_copy_pages + PAGES_FOR_IO +
- nr_copy_pages/PBES_PER_PAGE + !!(nr_copy_pages%PBES_PER_PAGE));
+ 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(struct pbe *pblist, unsigned int nr_pages)
+{
+ struct swap_map_page *swap_map;
+ struct swap_map_handle handle;
+ int error;
+
+ if (!enough_swap(nr_pages)) {
+ printk(KERN_ERR "swsusp: Not enough free swap\n");
+ return -ENOSPC;
+ }
+
+ init_header(nr_pages);
+ swap_map = alloc_swap_map(swsusp_info.pages);
+ if (!swap_map)
+ return -ENOMEM;
+ init_swap_map_handle(&handle, swap_map);
+
+ error = save_image_metadata(pblist, &handle);
+ if (!error)
+ error = save_image_data(pblist, &handle, nr_pages);
+ if (error)
+ goto Free_image_entries;
+
+ swap_map = reverse_swap_map(swap_map);
+ error = save_swap_map(swap_map, &swsusp_info.start);
+ if (error)
+ goto Free_map_entries;
+
+ error = close_swap();
+ if (error)
+ goto Free_map_entries;
+
+Free_swap_map:
+ free_swap_map(swap_map);
+ return error;
+
+Free_map_entries:
+ free_swap_map_entries(swap_map);
+Free_image_entries:
+ free_image_entries(swap_map);
+ goto Free_swap_map;
+}
/* 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 swsusp_write(struct pbe *pblist, unsigned int nr_pages)
{
int error;
- device_resume();
+
+ 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();
+ error = write_suspend_image(pblist, nr_pages);
/* This will unlock ignored swap devices since writing is finished */
lock_swapdevices();
return error;
-
}
-
-
int swsusp_suspend(void)
{
int error;
+
if ((error = arch_prepare_suspend()))
return error;
local_irq_disable();
*/
if ((error = device_power_down(PMSG_FREEZE))) {
printk(KERN_ERR "Some devices failed to power down, aborting suspend\n");
- local_irq_enable();
- return error;
+ goto Enable_irqs;
}
- if ((error = swsusp_swap_check())) {
- printk(KERN_ERR "swsusp: cannot find swap device, try swapon -a.\n");
- device_power_up();
- local_irq_enable();
- return error;
+ if ((error = save_highmem())) {
+ printk(KERN_ERR "swsusp: Not enough free pages for highmem\n");
+ goto Restore_highmem;
}
save_processor_state();
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;
}
* 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();
}
/**
- * On resume, for storing the PBE list and the image,
- * we can only use memory pages that do not conflict with the pages
- * which had been used before suspend.
- *
- * We don't know which pages are usable until we allocate them.
- *
- * Allocated but unusable (ie eaten) memory pages are linked together
- * to create a list, so that we can free them easily
- *
- * We could have used a type other than (void *)
- * for this purpose, but ...
+ * mark_unsafe_pages - mark the pages that cannot be used for storing
+ * the image during resume, because they conflict with the pages that
+ * had been used before suspend
*/
-static void **eaten_memory = NULL;
-
-static inline void eat_page(void *page)
-{
- void **c;
-
- c = eaten_memory;
- eaten_memory = page;
- *eaten_memory = c;
-}
-unsigned long get_usable_page(gfp_t gfp_mask)
-{
- unsigned long m;
-
- m = get_zeroed_page(gfp_mask);
- while (!PageNosaveFree(virt_to_page(m))) {
- eat_page((void *)m);
- m = get_zeroed_page(gfp_mask);
- if (!m)
- break;
- }
- return m;
-}
-
-void free_eaten_memory(void)
-{
- unsigned long m;
- void **c;
- int i = 0;
-
- c = eaten_memory;
- while (c) {
- m = (unsigned long)c;
- c = *c;
- free_page(m);
- i++;
- }
- eaten_memory = NULL;
- pr_debug("swsusp: %d unused pages freed\n", i);
-}
-
-/**
- * check_pagedir - We ensure here that pages that the PBEs point to
- * won't collide with pages where we're going to restore from the loaded
- * pages later
- */
-
-static int check_pagedir(struct pbe *pblist)
-{
- struct pbe *p;
-
- /* This is necessary, so that we can free allocated pages
- * in case of failure
- */
- for_each_pbe (p, pblist)
- p->address = 0UL;
-
- for_each_pbe (p, pblist) {
- p->address = get_usable_page(GFP_ATOMIC);
- if (!p->address)
- return -ENOMEM;
- }
- return 0;
-}
-
-/**
- * swsusp_pagedir_relocate - It is possible, that some memory pages
- * occupied by the list of PBEs collide with pages where we're going to
- * restore from the loaded pages later. We relocate them here.
- */
-
-static struct pbe * swsusp_pagedir_relocate(struct pbe *pblist)
+static void mark_unsafe_pages(struct pbe *pblist)
{
struct zone *zone;
unsigned long zone_pfn;
- struct pbe *pbpage, *tail, *p;
- void *m;
- int rel = 0, error = 0;
+ struct pbe *p;
if (!pblist) /* a sanity check */
- return NULL;
-
- pr_debug("swsusp: Relocating pagedir (%lu pages to check)\n",
- swsusp_info.pagedir_pages);
-
- /* Set page flags */
+ return;
+ /* Clear page flags */
for_each_zone (zone) {
- for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
- SetPageNosaveFree(pfn_to_page(zone_pfn +
+ for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn)
+ if (pfn_valid(zone_pfn + zone->zone_start_pfn))
+ ClearPageNosaveFree(pfn_to_page(zone_pfn +
zone->zone_start_pfn));
}
- /* Clear orig addresses */
-
+ /* Mark orig addresses */
for_each_pbe (p, pblist)
- ClearPageNosaveFree(virt_to_page(p->orig_address));
-
- tail = pblist + PB_PAGE_SKIP;
-
- /* Relocate colliding pages */
+ SetPageNosaveFree(virt_to_page(p->orig_address));
- for_each_pb_page (pbpage, pblist) {
- if (!PageNosaveFree(virt_to_page((unsigned long)pbpage))) {
- m = (void *)get_usable_page(GFP_ATOMIC | __GFP_COLD);
- if (!m) {
- error = -ENOMEM;
- break;
- }
- memcpy(m, (void *)pbpage, PAGE_SIZE);
- if (pbpage == pblist)
- pblist = (struct pbe *)m;
- else
- tail->next = (struct pbe *)m;
-
- eat_page((void *)pbpage);
- pbpage = (struct pbe *)m;
-
- /* We have to link the PBEs again */
-
- for (p = pbpage; p < pbpage + PB_PAGE_SKIP; p++)
- if (p->next) /* needed to save the end */
- p->next = p + 1;
+}
- rel++;
- }
- tail = pbpage + PB_PAGE_SKIP;
+static void copy_page_backup_list(struct pbe *dst, struct pbe *src)
+{
+ /* We assume both lists contain the same number of elements */
+ while (src) {
+ dst->orig_address = src->orig_address;
+ dst = dst->next;
+ src = src->next;
}
-
- if (error) {
- printk("\nswsusp: Out of memory\n\n");
- free_pagedir(pblist);
- free_eaten_memory();
- pblist = NULL;
- /* Is this even worth handling? It should never ever happen, and we
- have just lost user's state, anyway... */
- } else
- printk("swsusp: Relocated %d pages\n", rel);
-
- return pblist;
}
/*
static atomic_t io_done = ATOMIC_INIT(0);
-static int end_io(struct bio * bio, unsigned int num, int err)
+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");
return 0;
}
-static struct block_device * resume_bdev;
+static struct block_device *resume_bdev;
/**
* submit - submit BIO request.
* Then submit it and wait.
*/
-static int submit(int rw, pgoff_t page_off, void * page)
+static int submit(int rw, pgoff_t page_off, void *page)
{
int error = 0;
- struct bio * bio;
+ struct bio *bio;
bio = bio_alloc(GFP_ATOMIC, 1);
if (!bio)
return error;
}
-static int bio_read_page(pgoff_t page_off, void * page)
+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)
+static int bio_write_page(pgoff_t page_off, void *page)
{
return submit(WRITE, page_off, page);
}
+/**
+ * The following functions allow us to read data using a swap map
+ * in a file-alike way
+ */
+
+static inline void release_swap_map_reader(struct swap_map_handle *handle)
+{
+ if (handle->cur)
+ free_page((unsigned long)handle->cur);
+ handle->cur = NULL;
+}
+
+static inline int get_swap_map_reader(struct swap_map_handle *handle,
+ swp_entry_t start)
+{
+ int error;
+
+ if (!swp_offset(start))
+ return -EINVAL;
+ handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_ATOMIC);
+ if (!handle->cur)
+ return -ENOMEM;
+ error = bio_read_page(swp_offset(start), handle->cur);
+ if (error) {
+ release_swap_map_reader(handle);
+ return error;
+ }
+ handle->k = 0;
+ return 0;
+}
+
+static inline int swap_map_read_page(struct swap_map_handle *handle, void *buf)
+{
+ unsigned long offset;
+ int error;
+
+ if (!handle->cur)
+ return -EINVAL;
+ offset = swp_offset(handle->cur->entries[handle->k]);
+ if (!offset)
+ return -EINVAL;
+ error = bio_read_page(offset, buf);
+ if (error)
+ return error;
+ if (++handle->k >= MAP_PAGE_SIZE) {
+ handle->k = 0;
+ offset = swp_offset(handle->cur->next_swap);
+ if (!offset)
+ release_swap_map_reader(handle);
+ else
+ error = bio_read_page(offset, handle->cur);
+ }
+ 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)
+static const char *sanity_check(void)
{
dump_info();
if (swsusp_info.version_code != LINUX_VERSION_CODE)
return NULL;
}
-
static int check_header(void)
{
- const char * reason = NULL;
+ const char *reason = NULL;
int error;
if ((error = bio_read_page(swp_offset(swsusp_header.swsusp_info), &swsusp_info)))
printk(KERN_ERR "swsusp: Resume mismatch: %s\n",reason);
return -EPERM;
}
- nr_copy_pages = swsusp_info.image_pages;
return error;
}
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 {
+ } else {
return -EINVAL;
}
if (!error)
}
/**
- * data_read - Read image pages from swap.
- *
- * You do not need to check for overlaps, check_pagedir()
- * already did that.
+ * load_image_data - load the image data using the swap map handle
+ * @handle and store them using the page backup list @pblist
+ * (assume there are @nr_pages pages to load)
*/
-static int data_read(struct pbe *pblist)
+static int load_image_data(struct pbe *pblist,
+ struct swap_map_handle *handle,
+ unsigned int nr_pages)
{
- struct pbe * p;
- int error = 0;
- int i = 0;
- int mod = swsusp_info.image_pages / 100;
- void *tfm;
-
- if ((error = crypto_init(0, &tfm)))
- return error;
-
- if (!mod)
- mod = 1;
-
- printk("swsusp: Reading image data (%lu pages): ",
- swsusp_info.image_pages);
-
- for_each_pbe (p, pblist) {
- if (!(i % mod))
- printk("\b\b\b\b%3d%%", i / mod);
-
- if ((error = crypto_read(p, tfm))) {
- crypto_exit(tfm);
- return error;
- }
+ int error;
+ unsigned int m;
+ struct pbe *p;
- i++;
+ if (!pblist)
+ return -EINVAL;
+ printk("Loading image data pages (%u pages) ... ", nr_pages);
+ m = nr_pages / 100;
+ if (!m)
+ m = 1;
+ nr_pages = 0;
+ p = pblist;
+ while (p) {
+ error = swap_map_read_page(handle, (void *)p->address);
+ if (error)
+ break;
+ p = p->next;
+ if (!(nr_pages % m))
+ printk("\b\b\b\b%3d%%", nr_pages / m);
+ nr_pages++;
}
- printk("\b\b\b\bdone\n");
- crypto_exit(tfm);
+ if (!error)
+ printk("\b\b\b\bdone\n");
return error;
}
/**
- * read_pagedir - Read page backup list pages from swap
+ * unpack_orig_addresses - copy the elements of @buf[] (1 page) to
+ * the PBEs in the list starting at @pbe
*/
-static int read_pagedir(struct pbe *pblist)
+static inline struct pbe *unpack_orig_addresses(unsigned long *buf,
+ struct pbe *pbe)
{
- struct pbe *pbpage, *p;
- unsigned i = 0;
- int error;
+ int j;
- if (!pblist)
- return -EFAULT;
+ for (j = 0; j < PAGE_SIZE / sizeof(long) && pbe; j++) {
+ pbe->orig_address = buf[j];
+ pbe = pbe->next;
+ }
+ return pbe;
+}
- printk("swsusp: Reading pagedir (%lu pages)\n",
- swsusp_info.pagedir_pages);
+/**
+ * load_image_metadata - load the image metadata using the swap map
+ * handle @handle and put them into the PBEs in the list @pblist
+ */
- for_each_pb_page (pbpage, pblist) {
- unsigned long offset = swp_offset(swsusp_info.pagedir[i++]);
+static int load_image_metadata(struct pbe *pblist, struct swap_map_handle *handle)
+{
+ struct pbe *p;
+ unsigned long *buf;
+ unsigned int n = 0;
+ int error = 0;
- error = -EFAULT;
- if (offset) {
- p = (pbpage + PB_PAGE_SKIP)->next;
- error = bio_read_page(offset, (void *)pbpage);
- (pbpage + PB_PAGE_SKIP)->next = p;
- }
+ printk("Loading image metadata ... ");
+ buf = (unsigned long *)get_zeroed_page(GFP_ATOMIC);
+ if (!buf)
+ return -ENOMEM;
+ p = pblist;
+ while (p) {
+ error = swap_map_read_page(handle, buf);
if (error)
break;
+ p = unpack_orig_addresses(buf, p);
+ n++;
}
-
- if (error)
- free_pagedir(pblist);
- else
- BUG_ON(i != swsusp_info.pagedir_pages);
-
+ free_page((unsigned long)buf);
+ if (!error)
+ printk("done (%u pages loaded)\n", n);
return error;
}
-
static int check_suspend_image(void)
{
int error = 0;
return 0;
}
-static int read_suspend_image(void)
+static int read_suspend_image(struct pbe **pblist_ptr)
{
int error = 0;
- struct pbe *p;
+ struct pbe *p, *pblist;
+ struct swap_map_handle handle;
+ unsigned int nr_pages = swsusp_info.image_pages;
- if (!(p = alloc_pagedir(nr_copy_pages)))
+ p = alloc_pagedir(nr_pages, GFP_ATOMIC, 0);
+ if (!p)
return -ENOMEM;
-
- if ((error = read_pagedir(p)))
+ error = get_swap_map_reader(&handle, swsusp_info.start);
+ if (error)
+ /* The PBE list at p will be released by swsusp_free() */
return error;
-
- create_pbe_list(p, nr_copy_pages);
-
- if (!(pagedir_nosave = swsusp_pagedir_relocate(p)))
- return -ENOMEM;
-
- /* Allocate memory for the image and read the data from swap */
-
- error = check_pagedir(pagedir_nosave);
-
- if (!error)
- error = data_read(pagedir_nosave);
-
- if (error) { /* We fail cleanly */
- free_eaten_memory();
- for_each_pbe (p, pagedir_nosave)
- if (p->address) {
- free_page(p->address);
- p->address = 0UL;
- }
- free_pagedir(pagedir_nosave);
+ error = load_image_metadata(p, &handle);
+ if (!error) {
+ mark_unsafe_pages(p);
+ pblist = alloc_pagedir(nr_pages, GFP_ATOMIC, 1);
+ if (pblist)
+ copy_page_backup_list(pblist, p);
+ free_pagedir(p);
+ if (!pblist)
+ error = -ENOMEM;
+
+ /* Allocate memory for the image and read the data from swap */
+ if (!error)
+ error = alloc_data_pages(pblist, GFP_ATOMIC, 1);
+ if (!error)
+ error = load_image_data(pblist, &handle, nr_pages);
+ if (!error)
+ *pblist_ptr = pblist;
}
+ release_swap_map_reader(&handle);
return error;
}
* swsusp_read - Read saved image from swap.
*/
-int swsusp_read(void)
+int swsusp_read(struct pbe **pblist_ptr)
{
int error;
return PTR_ERR(resume_bdev);
}
- error = read_suspend_image();
+ error = read_suspend_image(pblist_ptr);
blkdev_put(resume_bdev);
- memset(key_iv, 0, MAXKEY+MAXIV);
if (!error)
pr_debug("swsusp: Reading resume file was successful\n");
git://ftp.safe.ca / safe / jmp / linux-2.6 / blobdiff