* Fixed runaway init
*
* Rafael J. Wysocki <rjw@sisk.pl>
- * Added the swap map data structure and reworked the handling of swap
+ * Reworked the freeing of memory and the handling of swap
*
* More state savers are welcome. Especially for the scsi layer...
*
* For TODOs,FIXMEs also look in Documentation/power/swsusp.txt
*/
-#include <linux/module.h>
#include <linux/mm.h>
#include <linux/suspend.h>
-#include <linux/smp_lock.h>
-#include <linux/file.h>
-#include <linux/utsname.h>
-#include <linux/version.h>
-#include <linux/delay.h>
-#include <linux/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/time.h>
#include "power.h"
*/
unsigned long image_size = 500 * 1024 * 1024;
+int in_suspend __nosavedata = 0;
+
#ifdef CONFIG_HIGHMEM
unsigned int count_highmem_pages(void);
-int save_highmem(void);
int restore_highmem(void);
#else
-static int save_highmem(void) { return 0; }
-static int restore_highmem(void) { return 0; }
-static unsigned int count_highmem_pages(void) { return 0; }
+static inline int restore_highmem(void) { return 0; }
+static inline unsigned int count_highmem_pages(void) { return 0; }
#endif
-extern char resume_file[];
-
-#define SWSUSP_SIG "S1SUSPEND"
-
-static struct swsusp_header {
- char reserved[PAGE_SIZE - 20 - sizeof(swp_entry_t)];
- swp_entry_t image;
- char orig_sig[10];
- char sig[10];
-} __attribute__((packed, aligned(PAGE_SIZE))) swsusp_header;
-
-static struct swsusp_info swsusp_info;
-
-/*
- * Saving part...
- */
-
-static unsigned short root_swap = 0xffff;
-
-static int mark_swapfiles(swp_entry_t start)
-{
- int error;
-
- rw_swap_page_sync(READ,
- swp_entry(root_swap, 0),
- virt_to_page((unsigned long)&swsusp_header));
- if (!memcmp("SWAP-SPACE",swsusp_header.sig, 10) ||
- !memcmp("SWAPSPACE2",swsusp_header.sig, 10)) {
- memcpy(swsusp_header.orig_sig,swsusp_header.sig, 10);
- memcpy(swsusp_header.sig,SWSUSP_SIG, 10);
- swsusp_header.image = start;
- 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 inline 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;
-
- spin_lock(&swap_lock);
- for (i = 0; i < MAX_SWAPFILES; i++) {
- if (!(swap_info[i].flags & SWP_WRITEOK))
- continue;
- if (!swsusp_resume_device || is_resume_device(swap_info + i)) {
- spin_unlock(&swap_lock);
- root_swap = i;
- return 0;
- }
- }
- spin_unlock(&swap_lock);
- return -ENODEV;
-}
-
/**
- * write_page - Write one page to a fresh swap location.
- * @addr: Address we're writing.
- * @loc: Place to store the entry we used.
+ * The following functions are used for tracing the allocated
+ * swap pages, so that they can be freed in case of an error.
*
- * 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.
+ * The functions operate on a linked bitmap structure defined
+ * in power.h
*/
-static int write_page(unsigned long addr, swp_entry_t *loc)
-{
- swp_entry_t entry;
- int error = -ENOSPC;
- entry = get_swap_page_of_type(root_swap);
- if (swp_offset(entry)) {
- error = rw_swap_page_sync(WRITE, entry, virt_to_page(addr));
- if (!error || error == -EIO)
- *loc = entry;
- }
- 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 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.
- *
- * 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.
- */
-
-#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)
+void free_bitmap(struct bitmap_page *bitmap)
{
- struct swap_map_page *swp;
+ struct bitmap_page *bp;
- while (swap_map) {
- swp = swap_map->next;
- free_page((unsigned long)swap_map);
- swap_map = swp;
+ while (bitmap) {
+ bp = bitmap->next;
+ free_page((unsigned long)bitmap);
+ bitmap = bp;
}
}
-static struct swap_map_page *alloc_swap_map(unsigned int nr_pages)
+struct bitmap_page *alloc_bitmap(unsigned int nr_bits)
{
- struct swap_map_page *swap_map, *swp;
- unsigned n = 0;
+ struct bitmap_page *bitmap, *bp;
+ unsigned int n;
- if (!nr_pages)
+ if (!nr_bits)
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);
+ bitmap = (struct bitmap_page *)get_zeroed_page(GFP_KERNEL);
+ bp = bitmap;
+ for (n = BITMAP_PAGE_BITS; n < nr_bits; n += BITMAP_PAGE_BITS) {
+ bp->next = (struct bitmap_page *)get_zeroed_page(GFP_KERNEL);
+ bp = bp->next;
+ if (!bp) {
+ free_bitmap(bitmap);
return NULL;
}
}
- return swap_map;
+ return bitmap;
}
-/**
- * reverse_swap_map - reverse the order of pages in the swap map
- * @swap_map
- */
-
-static inline struct swap_map_page *reverse_swap_map(struct swap_map_page *swap_map)
+static int bitmap_set(struct bitmap_page *bitmap, unsigned long bit)
{
- struct swap_map_page *prev, *next;
+ unsigned int n;
- prev = NULL;
- while (swap_map) {
- next = swap_map->next;
- swap_map->next = prev;
- prev = swap_map;
- swap_map = next;
+ n = BITMAP_PAGE_BITS;
+ while (bitmap && n <= bit) {
+ n += BITMAP_PAGE_BITS;
+ bitmap = bitmap->next;
}
- return prev;
-}
-
-/**
- * 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;
- }
-}
-
-/**
- * save_swap_map - save the swap map used for tracing the data pages
- * stored in the swap
- */
-
-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;
- swap_map = swap_map->next;
+ if (!bitmap)
+ return -EINVAL;
+ n -= BITMAP_PAGE_BITS;
+ bit -= n;
+ n = 0;
+ while (bit >= BITS_PER_CHUNK) {
+ bit -= BITS_PER_CHUNK;
+ n++;
}
- *start = entry;
+ bitmap->chunks[n] |= (1UL << bit);
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;
- }
-}
-
-/**
- * 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)
+sector_t alloc_swapdev_block(int swap, struct bitmap_page *bitmap)
{
- handle->cur = map;
- handle->k = 0;
-}
-
-static inline int swap_map_write_page(struct swap_map_handle *handle,
- unsigned long addr)
-{
- int error;
+ unsigned long offset;
- 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;
+ offset = swp_offset(get_swap_page_of_type(swap));
+ if (offset) {
+ if (bitmap_set(bitmap, offset))
+ swap_free(swp_entry(swap, offset));
+ else
+ return swapdev_block(swap, offset);
}
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;
-}
-
-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 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.cpus = num_online_cpus();
- swsusp_info.image_pages = nr_pages;
- swsusp_info.pages = nr_pages +
- ((nr_pages * sizeof(long) + PAGE_SIZE - 1) >> PAGE_SHIFT) + 1;
-}
-
-/**
- * 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 inline struct pbe *pack_orig_addresses(unsigned long *buf,
- struct pbe *pbe)
+void free_all_swap_pages(int swap, struct bitmap_page *bitmap)
{
- int j;
+ unsigned int bit, n;
+ unsigned long test;
- for (j = 0; j < PAGE_SIZE / sizeof(long) && pbe; j++) {
- buf[j] = pbe->orig_address;
- pbe = pbe->next;
+ bit = 0;
+ while (bitmap) {
+ for (n = 0; n < BITMAP_PAGE_CHUNKS; n++)
+ for (test = 1UL; test; test <<= 1) {
+ if (bitmap->chunks[n] & test)
+ swap_free(swp_entry(swap, bit));
+ bit++;
+ }
+ bitmap = bitmap->next;
}
- if (!pbe)
- for (; j < PAGE_SIZE / sizeof(long); j++)
- buf[j] = 0;
- return pbe;
}
/**
- * save_image_metadata - save the .orig_address fields of the PBEs
- * from the list @pblist using the swap map handle @handle
- */
-
-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;
-
- 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++;
- }
- free_page((unsigned long)buf);
- if (!error)
- printk("done (%u pages saved)\n", n);
- return error;
-}
-
-/**
- * enough_swap - Make sure we have enough swap to save the image.
+ * swsusp_show_speed - print the time elapsed between two events represented by
+ * @start and @stop
*
- * Returns TRUE or FALSE after checking the total amount of swap
- * space avaiable from the resume partition.
+ * @nr_pages - number of pages processed between @start and @stop
+ * @msg - introductory message to print
*/
-static int enough_swap(unsigned int nr_pages)
+void swsusp_show_speed(struct timeval *start, struct timeval *stop,
+ unsigned nr_pages, char *msg)
{
- unsigned int free_swap = swap_info[root_swap].pages -
- swap_info[root_swap].inuse_pages;
+ s64 elapsed_centisecs64;
+ int centisecs;
+ int k;
+ int kps;
- pr_debug("swsusp: free swap pages: %u\n", free_swap);
- return free_swap > (nr_pages + PAGES_FOR_IO +
- (nr_pages + PBES_PER_PAGE - 1) / PBES_PER_PAGE);
-}
-
-/**
- * swsusp_write - Write entire image and metadata.
- *
- * 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(struct pbe *pblist, unsigned int nr_pages)
-{
- struct swap_map_page *swap_map;
- struct swap_map_handle handle;
- swp_entry_t start;
- int error;
-
- if ((error = swsusp_swap_check())) {
- printk(KERN_ERR "swsusp: Cannot find swap device, try swapon -a.\n");
- return 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 = swap_map_write_page(&handle, (unsigned long)&swsusp_info);
- if (!error)
- 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, &start);
- if (error)
- goto Free_map_entries;
-
- dump_info();
- printk( "S" );
- error = mark_swapfiles(start);
- printk( "|\n" );
- 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;
+ elapsed_centisecs64 = timeval_to_ns(stop) - timeval_to_ns(start);
+ do_div(elapsed_centisecs64, NSEC_PER_SEC / 100);
+ centisecs = elapsed_centisecs64;
+ if (centisecs == 0)
+ centisecs = 1; /* avoid div-by-zero */
+ k = nr_pages * (PAGE_SIZE / 1024);
+ kps = (k * 100) / centisecs;
+ printk("%s %d kbytes in %d.%02d seconds (%d.%02d MB/s)\n", msg, k,
+ centisecs / 100, centisecs % 100,
+ kps / 1000, (kps % 1000) / 10);
}
/**
*/
#define SHRINK_BITE 10000
+static inline unsigned long __shrink_memory(long tmp)
+{
+ if (tmp > SHRINK_BITE)
+ tmp = SHRINK_BITE;
+ return shrink_all_memory(tmp);
+}
int swsusp_shrink_memory(void)
{
- long size, tmp;
+ long tmp;
struct zone *zone;
unsigned long pages = 0;
unsigned int i = 0;
char *p = "-\\|/";
+ struct timeval start, stop;
printk("Shrinking memory... ");
+ do_gettimeofday(&start);
do {
- size = 2 * count_highmem_pages();
- size += size / 50 + count_data_pages();
- size += (size + PBES_PER_PAGE - 1) / PBES_PER_PAGE +
- PAGES_FOR_IO;
+ long size, highmem_size;
+
+ highmem_size = count_highmem_pages();
+ size = count_data_pages() + PAGES_FOR_IO;
tmp = size;
+ size += highmem_size;
for_each_zone (zone)
- if (!is_highmem(zone))
- tmp -= zone->free_pages;
+ if (populated_zone(zone)) {
+ if (is_highmem(zone)) {
+ highmem_size -= zone->free_pages;
+ } else {
+ tmp -= zone->free_pages;
+ tmp += zone->lowmem_reserve[ZONE_NORMAL];
+ tmp += snapshot_additional_pages(zone);
+ }
+ }
+
+ if (highmem_size < 0)
+ highmem_size = 0;
+
+ tmp += highmem_size;
if (tmp > 0) {
- tmp = shrink_all_memory(SHRINK_BITE);
+ tmp = __shrink_memory(tmp);
if (!tmp)
return -ENOMEM;
pages += tmp;
} else if (size > image_size / PAGE_SIZE) {
- tmp = shrink_all_memory(SHRINK_BITE);
+ tmp = __shrink_memory(size - (image_size / PAGE_SIZE));
pages += tmp;
}
printk("\b%c", p[i++%4]);
} while (tmp > 0);
+ do_gettimeofday(&stop);
printk("\bdone (%lu pages freed)\n", pages);
+ swsusp_show_speed(&start, &stop, pages, "Freed");
return 0;
}
if ((error = arch_prepare_suspend()))
return error;
+
local_irq_disable();
/* At this point, device_suspend() has been called, but *not*
* device_power_down(). We *must* device_power_down() now.
goto Enable_irqs;
}
- if ((error = save_highmem())) {
- printk(KERN_ERR "swsusp: Not enough free pages for highmem\n");
- goto Restore_highmem;
- }
-
save_processor_state();
if ((error = swsusp_arch_suspend()))
printk(KERN_ERR "Error %d suspending\n", error);
/* Restore control flow magically appears here */
restore_processor_state();
-Restore_highmem:
- restore_highmem();
+ /* NOTE: device_power_up() is just a resume() for devices
+ * that suspended with irqs off ... no overall powerup.
+ */
device_power_up();
-Enable_irqs:
+ Enable_irqs:
local_irq_enable();
return error;
}
int swsusp_resume(void)
{
int error;
+
local_irq_disable();
- if (device_power_down(PMSG_FREEZE))
+ /* NOTE: device_power_down() is just a suspend() with irqs off;
+ * it has no special "power things down" semantics
+ */
+ if (device_power_down(PMSG_PRETHAW))
printk(KERN_ERR "Some devices failed to power down, very bad\n");
/* We'll ignore saved state, but this gets preempt count (etc) right */
save_processor_state();
- error = swsusp_arch_resume();
- /* Code below is only ever reached in case of failure. Otherwise
- * execution continues at place where swsusp_arch_suspend was called
- */
- BUG_ON(!error);
+ error = restore_highmem();
+ if (!error) {
+ error = swsusp_arch_resume();
+ /* The code below is only ever reached in case of a failure.
+ * Otherwise execution continues at place where
+ * swsusp_arch_suspend() was called
+ */
+ BUG_ON(!error);
+ /* This call to restore_highmem() undos the previous one */
+ restore_highmem();
+ }
/* The only reason why swsusp_arch_resume() can fail is memory being
* very tight, so we have to free it as soon as we can to avoid
* subsequent failures
*/
swsusp_free();
restore_processor_state();
- restore_highmem();
touch_softlockup_watchdog();
device_power_up();
local_irq_enable();
return error;
}
-
-/**
- * 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 mark_unsafe_pages(struct pbe *pblist)
-{
- struct zone *zone;
- unsigned long zone_pfn;
- struct pbe *p;
-
- if (!pblist) /* a sanity check */
- return;
-
- /* Clear page flags */
- for_each_zone (zone) {
- 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));
- }
-
- /* Mark orig addresses */
- for_each_pbe (p, pblist)
- SetPageNosaveFree(virt_to_page(p->orig_address));
-
-}
-
-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;
- }
-}
-
-/*
- * 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->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;
- }
-
-
- atomic_set(&io_done, 1);
- submit_bio(rw | (1 << BIO_RW_SYNC), bio);
- while (atomic_read(&io_done))
- yield();
- if (rw == READ)
- bio_set_pages_dirty(bio);
- 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);
-}
-
-/**
- * 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;
-}
-
-static int check_header(void)
-{
- char *reason = NULL;
-
- dump_info();
- if (swsusp_info.version_code != LINUX_VERSION_CODE)
- reason = "kernel version";
- if (swsusp_info.num_physpages != num_physpages)
- reason = "memory size";
- if (strcmp(swsusp_info.uts.sysname,system_utsname.sysname))
- reason = "system type";
- if (strcmp(swsusp_info.uts.release,system_utsname.release))
- reason = "kernel release";
- if (strcmp(swsusp_info.uts.version,system_utsname.version))
- reason = "version";
- if (strcmp(swsusp_info.uts.machine,system_utsname.machine))
- reason = "machine";
- if (reason) {
- printk(KERN_ERR "swsusp: Resume mismatch: %s\n", reason);
- return -EPERM;
- }
- return 0;
-}
-
-/**
- * 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 load_image_data(struct pbe *pblist,
- struct swap_map_handle *handle,
- unsigned int nr_pages)
-{
- int error;
- unsigned int m;
- struct pbe *p;
-
- 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++;
- }
- if (!error)
- printk("\b\b\b\bdone\n");
- return error;
-}
-
-/**
- * unpack_orig_addresses - copy the elements of @buf[] (1 page) to
- * the PBEs in the list starting at @pbe
- */
-
-static inline struct pbe *unpack_orig_addresses(unsigned long *buf,
- struct pbe *pbe)
-{
- int j;
-
- for (j = 0; j < PAGE_SIZE / sizeof(long) && pbe; j++) {
- pbe->orig_address = buf[j];
- pbe = pbe->next;
- }
- return pbe;
-}
-
-/**
- * load_image_metadata - load the image metadata using the swap map
- * handle @handle and put them into the PBEs in the list @pblist
- */
-
-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;
-
- 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++;
- }
- free_page((unsigned long)buf);
- if (!error)
- printk("done (%u pages loaded)\n", n);
- return error;
-}
-
-int swsusp_read(struct pbe **pblist_ptr)
-{
- int error;
- struct pbe *p, *pblist;
- struct swap_map_handle handle;
- unsigned int nr_pages;
-
- if (IS_ERR(resume_bdev)) {
- pr_debug("swsusp: block device not initialised\n");
- return PTR_ERR(resume_bdev);
- }
-
- error = get_swap_map_reader(&handle, swsusp_header.image);
- if (!error)
- error = swap_map_read_page(&handle, &swsusp_info);
- if (!error)
- error = check_header();
- if (error)
- return error;
- nr_pages = swsusp_info.image_pages;
- p = alloc_pagedir(nr_pages, GFP_ATOMIC, 0);
- if (!p)
- return -ENOMEM;
- 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) {
- release_eaten_pages();
- error = load_image_data(pblist, &handle, nr_pages);
- }
- if (!error)
- *pblist_ptr = pblist;
- }
- release_swap_map_reader(&handle);
-
- blkdev_put(resume_bdev);
-
- if (!error)
- pr_debug("swsusp: Reading resume file was successful\n");
- else
- pr_debug("swsusp: Error %d resuming\n", error);
- return error;
-}
-
-/**
- * swsusp_check - Check for swsusp signature in the resume device
- */
-
-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);
- memset(&swsusp_header, 0, sizeof(swsusp_header));
- if ((error = bio_read_page(0, &swsusp_header)))
- return error;
- if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) {
- memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10);
- /* Reset swap signature now */
- error = bio_write_page(0, &swsusp_header);
- } else {
- return -EINVAL;
- }
- if (error)
- blkdev_put(resume_bdev);
- else
- pr_debug("swsusp: Signature found, resuming\n");
- } else {
- error = PTR_ERR(resume_bdev);
- }
-
- if (error)
- pr_debug("swsusp: Error %d check for resume file\n", error);
-
- return error;
-}
-
-/**
- * swsusp_close - close swap device.
- */
-
-void swsusp_close(void)
-{
- if (IS_ERR(resume_bdev)) {
- pr_debug("swsusp: block device not initialised\n");
- return;
- }
-
- blkdev_put(resume_bdev);
-}
git://git.onelab.eu / linux-2.6.git / blobdiff