diff options
Diffstat (limited to 'kernel/power/swsusp.c')
| -rw-r--r-- | kernel/power/swsusp.c | 1020 |
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; } |