From f577eb30afdc68233f25d4d82b04102129262365 Mon Sep 17 00:00:00 2001 From: "Rafael J. Wysocki" Date: Thu, 23 Mar 2006 02:59:59 -0800 Subject: [PATCH] swsusp: low level interface Introduce the low level interface that can be used for handling the snapshot of the system memory by the in-kernel swap-writing/reading code of swsusp and the userland interface code (to be introduced shortly). Also change the way in which swsusp records the allocated swap pages and, consequently, simplifies the in-kernel swap-writing/reading code (this is necessary for the userland interface too). To this end, it introduces two helper functions in mm/swapfile.c, so that the swsusp code does not refer directly to the swap internals. Signed-off-by: Rafael J. Wysocki Acked-by: Pavel Machek Signed-off-by: Adrian Bunk Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- kernel/power/swsusp.c | 723 ++++++++++++++++++-------------------------------- 1 file changed, 256 insertions(+), 467 deletions(-) (limited to 'kernel/power/swsusp.c') diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c index 4e90905f0e8..457084f5001 100644 --- a/kernel/power/swsusp.c +++ b/kernel/power/swsusp.c @@ -77,6 +77,8 @@ */ 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); @@ -98,8 +100,6 @@ static struct swsusp_header { char sig[10]; } __attribute__((packed, aligned(PAGE_SIZE))) swsusp_header; -static struct swsusp_info swsusp_info; - /* * Saving part... */ @@ -129,255 +129,261 @@ static int mark_swapfiles(swp_entry_t start) 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.) +/** + * swsusp_swap_check - check if the resume device is a swap device + * and get its index (if so) */ -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; - - if (!swsusp_resume_device) - return -ENODEV; - spin_lock(&swap_lock); - 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; - } + int res = swap_type_of(swsusp_resume_device); + + if (res >= 0) { + root_swap = res; + return 0; } - spin_unlock(&swap_lock); - return -ENODEV; + return res; } /** - * write_page - Write one page to a fresh swap location. - * @addr: Address we're writing. - * @loc: Place to store the entry we used. + * The bitmap is used for tracing allocated swap pages * - * 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 entire bitmap consists of a number of bitmap_page + * structures linked with the help of the .next member. + * Thus each page can be allocated individually, so we only + * need to make 0-order memory allocations to create + * the bitmap. */ -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; -} +#define BITMAP_PAGE_SIZE (PAGE_SIZE - sizeof(void *)) +#define BITMAP_PAGE_CHUNKS (BITMAP_PAGE_SIZE / sizeof(long)) +#define BITS_PER_CHUNK (sizeof(long) * 8) +#define BITMAP_PAGE_BITS (BITMAP_PAGE_CHUNKS * BITS_PER_CHUNK) + +struct bitmap_page { + unsigned long chunks[BITMAP_PAGE_CHUNKS]; + struct bitmap_page *next; +}; /** - * Swap map-handling functions + * The following functions are used for tracing the allocated + * swap pages, so that they can be freed in case of an error. * - * 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. + * The functions operate on a linked bitmap structure defined + * above */ -#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) +static 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) +static 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; - - prev = NULL; - while (swap_map) { - next = swap_map->next; - swap_map->next = prev; - prev = swap_map; - swap_map = next; + unsigned int n; + + n = BITMAP_PAGE_BITS; + while (bitmap && n <= bit) { + n += BITMAP_PAGE_BITS; + bitmap = bitmap->next; } - return prev; + if (!bitmap) + return -EINVAL; + n -= BITMAP_PAGE_BITS; + bit -= n; + n = 0; + while (bit >= BITS_PER_CHUNK) { + bit -= BITS_PER_CHUNK; + n++; + } + bitmap->chunks[n] |= (1UL << bit); + return 0; } -/** - * 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) +static unsigned long alloc_swap_page(int swap, struct bitmap_page *bitmap) { - while (swap_map) { - if (swap_map->next_swap.val) - swap_free(swap_map->next_swap); - swap_map = swap_map->next; + unsigned long offset; + + offset = swp_offset(get_swap_page_of_type(swap)); + if (offset) { + if (bitmap_set(bitmap, offset)) { + swap_free(swp_entry(swap, offset)); + offset = 0; + } } + return offset; } -/** - * 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) +static void free_all_swap_pages(int swap, struct bitmap_page *bitmap) { - swp_entry_t entry = (swp_entry_t){0}; - int error; + unsigned int bit, n; + unsigned long test; - while (swap_map) { - swap_map->next_swap = entry; - if ((error = write_page((unsigned long)swap_map, &entry))) - return error; - swap_map = swap_map->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; } - *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) + * write_page - Write one page to given swap location. + * @buf: Address we're writing. + * @offset: Offset of the swap page we're writing to. */ -static inline void free_image_entries(struct swap_map_page *swp) +static int write_page(void *buf, unsigned long offset) { - unsigned k; + swp_entry_t entry; + int error = -ENOSPC; - while (swp) { - for (k = 0; k < MAP_PAGE_SIZE; k++) - if (swp->entries[k].val) - swap_free(swp->entries[k]); - swp = swp->next; + if (offset) { + entry = swp_entry(root_swap, offset); + error = rw_swap_page_sync(WRITE, entry, virt_to_page(buf)); } + return error; } +/* + * The swap map is a data structure used for keeping track of each page + * written to a swap partition. It consists of many swap_map_page + * structures that contain each an array of MAP_PAGE_SIZE swap entries. + * These structures are stored on the swap and linked together with the + * help of the .next_swap member. + * + * The swap map is created during suspend. The swap map pages are + * allocated and populated one at a time, so we only need one memory + * page to set up the entire structure. + * + * During resume we also only need to use one swap_map_page structure + * at a time. + */ + +#define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(long) - 1) + +struct swap_map_page { + unsigned long entries[MAP_PAGE_ENTRIES]; + unsigned long next_swap; +}; + /** - * The swap_map_handle structure is used for handling the swap map in + * The swap_map_handle structure is used for handling swap in * a file-alike way */ struct swap_map_handle { struct swap_map_page *cur; + unsigned long cur_swap; + struct bitmap_page *bitmap; unsigned int k; }; -static inline void init_swap_map_handle(struct swap_map_handle *handle, - struct swap_map_page *map) +static void release_swap_writer(struct swap_map_handle *handle) { - handle->cur = map; + if (handle->cur) + free_page((unsigned long)handle->cur); + handle->cur = NULL; + if (handle->bitmap) + free_bitmap(handle->bitmap); + handle->bitmap = NULL; +} + +static int get_swap_writer(struct swap_map_handle *handle) +{ + handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL); + if (!handle->cur) + return -ENOMEM; + handle->bitmap = alloc_bitmap(count_swap_pages(root_swap, 0)); + if (!handle->bitmap) { + release_swap_writer(handle); + return -ENOMEM; + } + handle->cur_swap = alloc_swap_page(root_swap, handle->bitmap); + if (!handle->cur_swap) { + release_swap_writer(handle); + return -ENOSPC; + } handle->k = 0; + return 0; } -static inline int swap_map_write_page(struct swap_map_handle *handle, - unsigned long addr) +static int swap_write_page(struct swap_map_handle *handle, void *buf) { int error; + unsigned long offset; - error = write_page(addr, handle->cur->entries + handle->k); + if (!handle->cur) + return -EINVAL; + offset = alloc_swap_page(root_swap, handle->bitmap); + error = write_page(buf, offset); if (error) return error; - if (++handle->k >= MAP_PAGE_SIZE) { - handle->cur = handle->cur->next; + handle->cur->entries[handle->k++] = offset; + if (handle->k >= MAP_PAGE_ENTRIES) { + offset = alloc_swap_page(root_swap, handle->bitmap); + if (!offset) + return -ENOSPC; + handle->cur->next_swap = offset; + error = write_page(handle->cur, handle->cur_swap); + if (error) + return error; + memset(handle->cur, 0, PAGE_SIZE); + handle->cur_swap = offset; handle->k = 0; } return 0; } +static int flush_swap_writer(struct swap_map_handle *handle) +{ + if (handle->cur && handle->cur_swap) + return write_page(handle->cur, handle->cur_swap); + else + return -EINVAL; +} + /** - * 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) + * save_image - save the suspend image data */ -static int save_image_data(struct pbe *pblist, - struct swap_map_handle *handle, - unsigned int nr_pages) +static int save_image(struct swap_map_handle *handle, + struct snapshot_handle *snapshot, + unsigned int nr_pages) { unsigned int m; - struct pbe *p; + int ret; int error = 0; printk("Saving image data pages (%u pages) ... ", nr_pages); @@ -385,98 +391,22 @@ static int save_image_data(struct pbe *pblist, 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++; - } + do { + ret = snapshot_read_next(snapshot, PAGE_SIZE); + if (ret > 0) { + error = swap_write_page(handle, data_of(*snapshot)); + if (error) + break; + if (!(nr_pages % m)) + printk("\b\b\b\b%3d%%", nr_pages / m); + nr_pages++; + } + } while (ret > 0); 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) -{ - int j; - - 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; -} - -/** - * 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. * @@ -486,8 +416,7 @@ static int save_image_metadata(struct pbe *pblist, static int enough_swap(unsigned int nr_pages) { - unsigned int free_swap = swap_info[root_swap].pages - - swap_info[root_swap].inuse_pages; + unsigned int free_swap = count_swap_pages(root_swap, 1); pr_debug("swsusp: free swap pages: %u\n", free_swap); return free_swap > (nr_pages + PAGES_FOR_IO + @@ -503,57 +432,44 @@ static int enough_swap(unsigned int nr_pages) * correctly, we'll mark system clean, anyway.) */ -int swsusp_write(struct pbe *pblist, unsigned int nr_pages) +int swsusp_write(void) { - struct swap_map_page *swap_map; struct swap_map_handle handle; - swp_entry_t start; + struct snapshot_handle snapshot; + struct swsusp_info *header; + unsigned long 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)) { + memset(&snapshot, 0, sizeof(struct snapshot_handle)); + error = snapshot_read_next(&snapshot, PAGE_SIZE); + if (error < PAGE_SIZE) + return error < 0 ? error : -EFAULT; + header = (struct swsusp_info *)data_of(snapshot); + if (!enough_swap(header->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); + error = get_swap_writer(&handle); + if (!error) { + start = handle.cur_swap; + error = swap_write_page(&handle, header); + } 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" ); + error = save_image(&handle, &snapshot, header->pages - 1); + if (!error) { + flush_swap_writer(&handle); + printk("S"); + error = mark_swapfiles(swp_entry(root_swap, start)); + printk("|\n"); + } if (error) - goto Free_map_entries; - -Free_swap_map: - free_swap_map(swap_map); + free_all_swap_pages(root_swap, handle.bitmap); + release_swap_writer(&handle); return error; - -Free_map_entries: - free_swap_map_entries(swap_map); -Free_image_entries: - free_image_entries(swap_map); - goto Free_swap_map; } /** @@ -663,45 +579,6 @@ int swsusp_resume(void) 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 @@ -779,14 +656,14 @@ static int bio_write_page(pgoff_t page_off, void *page) * in a file-alike way */ -static inline void release_swap_map_reader(struct swap_map_handle *handle) +static void release_swap_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, +static int get_swap_reader(struct swap_map_handle *handle, swp_entry_t start) { int error; @@ -798,149 +675,80 @@ static inline int get_swap_map_reader(struct swap_map_handle *handle, return -ENOMEM; error = bio_read_page(swp_offset(start), handle->cur); if (error) { - release_swap_map_reader(handle); + release_swap_reader(handle); return error; } handle->k = 0; return 0; } -static inline int swap_map_read_page(struct swap_map_handle *handle, void *buf) +static int swap_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]); + offset = handle->cur->entries[handle->k]; if (!offset) - return -EINVAL; + return -EFAULT; error = bio_read_page(offset, buf); if (error) return error; - if (++handle->k >= MAP_PAGE_SIZE) { + if (++handle->k >= MAP_PAGE_ENTRIES) { handle->k = 0; - offset = swp_offset(handle->cur->next_swap); + offset = handle->cur->next_swap; if (!offset) - release_swap_map_reader(handle); + release_swap_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 + * load_image - load the image using the swap map handle + * @handle and the snapshot handle @snapshot * (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) +static int load_image(struct swap_map_handle *handle, + struct snapshot_handle *snapshot, + unsigned int nr_pages) { - int error; unsigned int m; - struct pbe *p; + int ret; + int error = 0; - 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++; - } + do { + ret = snapshot_write_next(snapshot, PAGE_SIZE); + if (ret > 0) { + error = swap_read_page(handle, data_of(*snapshot)); + if (error) + break; + if (!(nr_pages % m)) + printk("\b\b\b\b%3d%%", nr_pages / m); + nr_pages++; + } + } while (ret > 0); if (!error) printk("\b\b\b\bdone\n"); + if (!snapshot_image_loaded(snapshot)) + error = -ENODATA; 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 swsusp_read(void) { int error; - struct pbe *p, *pblist; struct swap_map_handle handle; + struct snapshot_handle snapshot; + struct swsusp_info *header; unsigned int nr_pages; if (IS_ERR(resume_bdev)) { @@ -948,38 +756,19 @@ int swsusp_read(struct pbe **pblist_ptr) return PTR_ERR(resume_bdev); } - error = get_swap_map_reader(&handle, swsusp_header.image); + memset(&snapshot, 0, sizeof(struct snapshot_handle)); + error = snapshot_write_next(&snapshot, PAGE_SIZE); + if (error < PAGE_SIZE) + return error < 0 ? error : -EFAULT; + header = (struct swsusp_info *)data_of(snapshot); + error = get_swap_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); + error = swap_read_page(&handle, header); 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; + nr_pages = header->image_pages; + error = load_image(&handle, &snapshot, nr_pages); } - release_swap_map_reader(&handle); + release_swap_reader(&handle); blkdev_put(resume_bdev); -- cgit v1.2.3-70-g09d2