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-rw-r--r--kernel/power/swsusp.c1020
1 files changed, 526 insertions, 494 deletions
diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c
index c05f46e7348f..55a18d26abed 100644
--- a/kernel/power/swsusp.c
+++ b/kernel/power/swsusp.c
@@ -30,8 +30,8 @@
* 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...
*
@@ -67,44 +67,33 @@
#include <asm/tlbflush.h>
#include <asm/io.h>
-#include <linux/random.h>
-#include <linux/crypto.h>
-#include <asm/scatterlist.h>
-
#include "power.h"
+/*
+ * Preferred image size in MB (tunable via /sys/power/image_size).
+ * When it is set to N, swsusp will do its best to ensure the image
+ * size will not exceed N MB, but if that is impossible, it will
+ * try to create the smallest image possible.
+ */
+unsigned int image_size = 500;
+
#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; }
#endif
-#define CIPHER "aes"
-#define MAXKEY 32
-#define MAXIV 32
-
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 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;
-
#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 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;
@@ -115,140 +104,9 @@ 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(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 unsigned short root_swap = 0xffff;
-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)
+static int mark_swapfiles(swp_entry_t start)
{
int error;
@@ -259,8 +117,7 @@ static int mark_swapfiles(swp_entry_t prev)
!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;
+ swsusp_header.image = start;
error = rw_swap_page_sync(WRITE,
swp_entry(root_swap, 0),
virt_to_page((unsigned long)
@@ -283,7 +140,7 @@ static int mark_swapfiles(swp_entry_t prev)
* 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)
+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;
@@ -294,54 +151,22 @@ static int is_resume_device(const struct swap_info_struct *swap_info)
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;
+ if (!swsusp_resume_device)
+ return -ENODEV;
spin_lock(&swap_lock);
- for (i = 0; i< MAX_SWAPFILES; i++)
- if (swapfile_used[i] == SWAPFILE_IGNORED) {
- swap_info[i].flags ^= SWP_WRITEOK;
+ for (i = 0; i < MAX_SWAPFILES; i++) {
+ if (!(swap_info[i].flags & SWP_WRITEOK))
+ continue;
+ if (is_resume_device(swap_info + i)) {
+ spin_unlock(&swap_lock);
+ root_swap = i;
+ return 0;
}
+ }
spin_unlock(&swap_lock);
+ return -ENODEV;
}
/**
@@ -359,72 +184,217 @@ static void lock_swapdevices(void)
static int write_page(unsigned long addr, swp_entry_t *loc)
{
swp_entry_t entry;
- int error = 0;
+ int error = -ENOSPC;
- 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)
+ 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;
- } else
- error = -ENOSPC;
+ }
return error;
}
/**
- * 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;
}
- printk("\b\b\b\bdone\n");
- crypto_exit(tfm);
+ *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;
+ }
+}
+
+/**
+ * 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;
}
@@ -440,70 +410,70 @@ static void dump_info(void)
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;
-}
-
-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;
+ swsusp_info.image_pages = nr_pages;
+ swsusp_info.pages = nr_pages +
+ ((nr_pages * sizeof(long) + PAGE_SIZE - 1) >> PAGE_SHIFT) + 1;
}
/**
- * 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)
{
- int error = 0;
+ unsigned long *buf;
unsigned int n = 0;
- struct pbe *pbe;
+ struct pbe *p;
+ int error = 0;
- 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);
+ free_page((unsigned long)buf);
+ if (!error)
+ printk("done (%u pages saved)\n", n);
return error;
}
@@ -511,75 +481,125 @@ static int write_pagedir(void)
* 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.
+ * space avaiable from the resume partition.
*/
static int enough_swap(unsigned int nr_pages)
{
- struct sysinfo i;
+ unsigned int free_swap = swap_info[root_swap].pages -
+ swap_info[root_swap].inuse_pages;
- si_swapinfo(&i);
- pr_debug("swsusp: available swap: %lu pages\n", i.freeswap);
- return i.freeswap > (nr_pages + PAGES_FOR_IO +
+ 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);
}
/**
- * write_suspend_image - Write entire image and metadata.
+ * 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.)
*/
-static int write_suspend_image(void)
+
+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 (!enough_swap(nr_copy_pages)) {
+ 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();
- if ((error = data_write()))
- goto FreeData;
+ 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;
- if ((error = write_pagedir()))
- goto FreePagedir;
+ swap_map = reverse_swap_map(swap_map);
+ error = save_swap_map(swap_map, &start);
+ if (error)
+ goto Free_map_entries;
- if ((error = close_swap()))
- goto FreePagedir;
- Done:
- memset(key_iv, 0, MAXKEY+MAXIV);
+ 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;
- FreePagedir:
- free_pagedir_entries();
- FreeData:
- data_free();
- goto Done;
+
+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.)
+/**
+ * swsusp_shrink_memory - Try to free as much memory as needed
+ *
+ * ... but do not OOM-kill anyone
+ *
+ * Notice: all userland should be stopped before it is called, or
+ * livelock is possible.
*/
-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;
-}
+#define SHRINK_BITE 10000
+int swsusp_shrink_memory(void)
+{
+ long size, tmp;
+ struct zone *zone;
+ unsigned long pages = 0;
+ unsigned int i = 0;
+ char *p = "-\\|/";
+
+ printk("Shrinking memory... ");
+ do {
+ size = 2 * count_highmem_pages();
+ size += size / 50 + count_data_pages();
+ size += (size + PBES_PER_PAGE - 1) / PBES_PER_PAGE +
+ PAGES_FOR_IO;
+ tmp = size;
+ for_each_zone (zone)
+ if (!is_highmem(zone))
+ tmp -= zone->free_pages;
+ if (tmp > 0) {
+ tmp = shrink_all_memory(SHRINK_BITE);
+ if (!tmp)
+ return -ENOMEM;
+ pages += tmp;
+ } else if (size > (image_size * 1024 * 1024) / PAGE_SIZE) {
+ tmp = shrink_all_memory(SHRINK_BITE);
+ pages += tmp;
+ }
+ printk("\b%c", p[i++%4]);
+ } while (tmp > 0);
+ printk("\bdone (%lu pages freed)\n", pages);
+ return 0;
+}
int swsusp_suspend(void)
{
@@ -677,7 +697,6 @@ 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->swap_address = src->swap_address;
dst = dst->next;
src = src->next;
}
@@ -757,198 +776,224 @@ static int bio_write_page(pgoff_t page_off, void *page)
return submit(WRITE, page_off, page);
}
-/*
- * 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..
+/**
+ * The following functions allow us to read data using a swap map
+ * in a file-alike way
*/
-static const char *sanity_check(void)
+static inline void release_swap_map_reader(struct swap_map_handle *handle)
{
- 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;
+ if (handle->cur)
+ free_page((unsigned long)handle->cur);
+ handle->cur = NULL;
}
-
-static int check_header(void)
+static inline int get_swap_map_reader(struct swap_map_handle *handle,
+ swp_entry_t start)
{
- const char *reason = NULL;
int error;
- if ((error = bio_read_page(swp_offset(swsusp_header.swsusp_info), &swsusp_info)))
+ 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;
-
- /* Is this same machine? */
- if ((reason = sanity_check())) {
- printk(KERN_ERR "swsusp: Resume mismatch: %s\n",reason);
- return -EPERM;
}
- nr_copy_pages = swsusp_info.image_pages;
- return error;
+ handle->k = 0;
+ return 0;
}
-static int check_sig(void)
+static inline int swap_map_read_page(struct swap_map_handle *handle, void *buf)
{
+ unsigned long offset;
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 {
+ 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);
}
- if (!error)
- pr_debug("swsusp: Signature found, resuming\n");
return error;
}
-/**
- * data_read - Read image pages from swap.
- *
- * You do not need to check for overlaps, check_pagedir()
- * already did that.
- */
-
-static int data_read(struct pbe *pblist)
+static int check_header(void)
{
- 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);
+ char *reason = NULL;
- if ((error = crypto_read(p, tfm))) {
- crypto_exit(tfm);
- return error;
- }
-
- i++;
+ 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;
}
- printk("\b\b\b\bdone\n");
- crypto_exit(tfm);
- return error;
+ return 0;
}
/**
- * read_pagedir - Read page backup list pages from swap
+ * 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 read_pagedir(struct pbe *pblist)
+static int load_image_data(struct pbe *pblist,
+ struct swap_map_handle *handle,
+ unsigned int nr_pages)
{
- struct pbe *pbpage, *p;
- unsigned int i = 0;
int error;
+ unsigned int m;
+ struct pbe *p;
if (!pblist)
- return -EFAULT;
-
- printk("swsusp: Reading pagedir (%lu pages)\n",
- swsusp_info.pagedir_pages);
-
- for_each_pb_page (pbpage, pblist) {
- unsigned long offset = swp_offset(swsusp_info.pagedir[i++]);
-
- error = -EFAULT;
- if (offset) {
- p = (pbpage + PB_PAGE_SKIP)->next;
- error = bio_read_page(offset, (void *)pbpage);
- (pbpage + PB_PAGE_SKIP)->next = p;
- }
+ 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)
- BUG_ON(i != swsusp_info.pagedir_pages);
-
+ 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 int check_suspend_image(void)
+static inline struct pbe *unpack_orig_addresses(unsigned long *buf,
+ struct pbe *pbe)
{
- int error = 0;
+ int j;
- if ((error = check_sig()))
- return error;
-
- if ((error = check_header()))
- return error;
-
- return 0;
+ for (j = 0; j < PAGE_SIZE / sizeof(long) && pbe; j++) {
+ pbe->orig_address = buf[j];
+ pbe = pbe->next;
+ }
+ return pbe;
}
-static int read_suspend_image(void)
+/**
+ * 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)
{
- int error = 0;
struct pbe *p;
+ unsigned long *buf;
+ unsigned int n = 0;
+ int error = 0;
- if (!(p = alloc_pagedir(nr_copy_pages, GFP_ATOMIC, 0)))
+ printk("Loading image metadata ... ");
+ buf = (unsigned long *)get_zeroed_page(GFP_ATOMIC);
+ if (!buf)
return -ENOMEM;
-
- if ((error = read_pagedir(p)))
- return error;
- create_pbe_list(p, nr_copy_pages);
- mark_unsafe_pages(p);
- pagedir_nosave = alloc_pagedir(nr_copy_pages, GFP_ATOMIC, 1);
- if (pagedir_nosave) {
- create_pbe_list(pagedir_nosave, nr_copy_pages);
- copy_page_backup_list(pagedir_nosave, p);
+ p = pblist;
+ while (p) {
+ error = swap_map_read_page(handle, buf);
+ if (error)
+ break;
+ p = unpack_orig_addresses(buf, p);
+ n++;
}
- free_pagedir(p);
- if (!pagedir_nosave)
- return -ENOMEM;
+ free_page((unsigned long)buf);
+ if (!error)
+ printk("done (%u pages loaded)\n", n);
+ return error;
+}
- /* Allocate memory for the image and read the data from swap */
+int swsusp_read(struct pbe **pblist_ptr)
+{
+ int error;
+ struct pbe *p, *pblist;
+ struct swap_map_handle handle;
+ unsigned int nr_pages;
- error = alloc_data_pages(pagedir_nosave, GFP_ATOMIC, 1);
+ 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 = data_read(pagedir_nosave);
+ 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 saved image in swap
+ * swsusp_check - Check for swsusp signature in the resume device
*/
int swsusp_check(void)
@@ -958,40 +1003,27 @@ int swsusp_check(void)
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();
+ 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
+ blkdev_put(resume_bdev);
+ else
+ pr_debug("swsusp: Signature found, resuming\n");
+ } 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: Error %d check for resume file\n", error);
- if (!error)
- pr_debug("swsusp: Reading resume file was successful\n");
- else
- pr_debug("swsusp: Error %d resuming\n", error);
return error;
}