diff options
Diffstat (limited to 'kernel/power/swsusp.c')
| -rw-r--r-- | kernel/power/swsusp.c | 887 |
1 files changed, 61 insertions, 826 deletions
diff --git a/kernel/power/swsusp.c b/kernel/power/swsusp.c index 2d9d08f72f76..c4016cbbd3e0 100644 --- a/kernel/power/swsusp.c +++ b/kernel/power/swsusp.c @@ -31,41 +31,24 @@ * Fixed runaway init * * Rafael J. Wysocki <rjw@sisk.pl> - * Added the swap map data structure and reworked the handling of swap + * Reworked the freeing of memory and the handling of swap * * More state savers are welcome. Especially for the scsi layer... * * For TODOs,FIXMEs also look in Documentation/power/swsusp.txt */ -#include <linux/module.h> #include <linux/mm.h> #include <linux/suspend.h> -#include <linux/smp_lock.h> -#include <linux/file.h> -#include <linux/utsname.h> -#include <linux/version.h> -#include <linux/delay.h> -#include <linux/bitops.h> #include <linux/spinlock.h> -#include <linux/genhd.h> #include <linux/kernel.h> #include <linux/major.h> #include <linux/swap.h> #include <linux/pm.h> -#include <linux/device.h> -#include <linux/buffer_head.h> #include <linux/swapops.h> #include <linux/bootmem.h> #include <linux/syscalls.h> #include <linux/highmem.h> -#include <linux/bio.h> - -#include <asm/uaccess.h> -#include <asm/mmu_context.h> -#include <asm/pgtable.h> -#include <asm/tlbflush.h> -#include <asm/io.h> #include "power.h" @@ -77,6 +60,8 @@ */ 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); @@ -87,471 +72,97 @@ static int restore_highmem(void) { return 0; } static unsigned int count_highmem_pages(void) { return 0; } #endif -extern char resume_file[]; - -#define SWSUSP_SIG "S1SUSPEND" - -static struct swsusp_header { - char reserved[PAGE_SIZE - 20 - sizeof(swp_entry_t)]; - swp_entry_t image; - char orig_sig[10]; - char sig[10]; -} __attribute__((packed, aligned(PAGE_SIZE))) swsusp_header; - -static struct swsusp_info swsusp_info; - -/* - * Saving part... - */ - -static unsigned short root_swap = 0xffff; - -static int mark_swapfiles(swp_entry_t start) -{ - int error; - - rw_swap_page_sync(READ, - swp_entry(root_swap, 0), - virt_to_page((unsigned long)&swsusp_header)); - if (!memcmp("SWAP-SPACE",swsusp_header.sig, 10) || - !memcmp("SWAPSPACE2",swsusp_header.sig, 10)) { - memcpy(swsusp_header.orig_sig,swsusp_header.sig, 10); - memcpy(swsusp_header.sig,SWSUSP_SIG, 10); - swsusp_header.image = start; - error = rw_swap_page_sync(WRITE, - swp_entry(root_swap, 0), - virt_to_page((unsigned long) - &swsusp_header)); - } else { - pr_debug("swsusp: Partition is not swap space.\n"); - error = -ENODEV; - } - return error; -} - -/* - * Check whether the swap device is the specified resume - * device, irrespective of whether they are specified by - * identical names. - * - * (Thus, device inode aliasing is allowed. You can say /dev/hda4 - * instead of /dev/ide/host0/bus0/target0/lun0/part4 [if using devfs] - * and they'll be considered the same device. This is *necessary* for - * devfs, since the resume code can only recognize the form /dev/hda4, - * but the suspend code would see the long name.) - */ -static inline int is_resume_device(const struct swap_info_struct *swap_info) -{ - struct file *file = swap_info->swap_file; - struct inode *inode = file->f_dentry->d_inode; - - return S_ISBLK(inode->i_mode) && - swsusp_resume_device == MKDEV(imajor(inode), iminor(inode)); -} - -static int swsusp_swap_check(void) /* This is called before saving image */ -{ - int i; - - spin_lock(&swap_lock); - for (i = 0; i < MAX_SWAPFILES; i++) { - if (!(swap_info[i].flags & SWP_WRITEOK)) - continue; - if (!swsusp_resume_device || is_resume_device(swap_info + i)) { - spin_unlock(&swap_lock); - root_swap = i; - return 0; - } - } - spin_unlock(&swap_lock); - return -ENODEV; -} - -/** - * write_page - Write one page to a fresh swap location. - * @addr: Address we're writing. - * @loc: Place to store the entry we used. - * - * 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. - */ -static int write_page(unsigned long addr, swp_entry_t *loc) -{ - swp_entry_t entry; - int error = -ENOSPC; - - entry = get_swap_page_of_type(root_swap); - if (swp_offset(entry)) { - error = rw_swap_page_sync(WRITE, entry, virt_to_page(addr)); - if (!error || error == -EIO) - *loc = entry; - } - return error; -} - /** - * Swap map-handling functions - * - * The swap map is a data structure used for keeping track of each page - * written to the swap. It consists of many swap_map_page structures - * that contain each an array of MAP_PAGE_SIZE swap entries. - * These structures are linked together with the help of either the - * .next (in memory) or the .next_swap (in swap) member. + * The 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 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 + * in power.h */ -#define MAP_PAGE_SIZE ((PAGE_SIZE - sizeof(swp_entry_t) - sizeof(void *)) \ - / sizeof(swp_entry_t)) - -struct swap_map_page { - swp_entry_t entries[MAP_PAGE_SIZE]; - swp_entry_t next_swap; - struct swap_map_page *next; -}; - -static inline void free_swap_map(struct swap_map_page *swap_map) +void free_bitmap(struct bitmap_page *bitmap) { - struct swap_map_page *swp; + struct bitmap_page *bp; - while (swap_map) { - swp = swap_map->next; - free_page((unsigned long)swap_map); - swap_map = swp; + while (bitmap) { + bp = bitmap->next; + free_page((unsigned long)bitmap); + bitmap = bp; } } -static struct swap_map_page *alloc_swap_map(unsigned int nr_pages) +struct bitmap_page *alloc_bitmap(unsigned int nr_bits) { - struct swap_map_page *swap_map, *swp; - unsigned n = 0; + struct bitmap_page *bitmap, *bp; + unsigned int n; - if (!nr_pages) + if (!nr_bits) return NULL; - pr_debug("alloc_swap_map(): nr_pages = %d\n", nr_pages); - swap_map = (struct swap_map_page *)get_zeroed_page(GFP_ATOMIC); - swp = swap_map; - for (n = MAP_PAGE_SIZE; n < nr_pages; n += MAP_PAGE_SIZE) { - swp->next = (struct swap_map_page *)get_zeroed_page(GFP_ATOMIC); - swp = swp->next; - if (!swp) { - free_swap_map(swap_map); + bitmap = (struct bitmap_page *)get_zeroed_page(GFP_KERNEL); + bp = bitmap; + for (n = BITMAP_PAGE_BITS; n < nr_bits; n += BITMAP_PAGE_BITS) { + bp->next = (struct bitmap_page *)get_zeroed_page(GFP_KERNEL); + bp = bp->next; + if (!bp) { + free_bitmap(bitmap); return NULL; } } - return swap_map; + return bitmap; } -/** - * reverse_swap_map - reverse the order of pages in the swap map - * @swap_map - */ - -static inline struct swap_map_page *reverse_swap_map(struct swap_map_page *swap_map) -{ - 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; -} - -/** - * free_swap_map_entries - free the swap entries allocated to store - * the swap map @swap_map (this is only called in case of an error) - */ -static inline void free_swap_map_entries(struct swap_map_page *swap_map) -{ - while (swap_map) { - if (swap_map->next_swap.val) - swap_free(swap_map->next_swap); - swap_map = swap_map->next; - } -} - -/** - * save_swap_map - save the swap map used for tracing the data pages - * stored in the swap - */ - -static int save_swap_map(struct swap_map_page *swap_map, swp_entry_t *start) -{ - swp_entry_t entry = (swp_entry_t){0}; - int error; - - while (swap_map) { - swap_map->next_swap = entry; - if ((error = write_page((unsigned long)swap_map, &entry))) - return error; - swap_map = swap_map->next; - } - *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) +static int bitmap_set(struct bitmap_page *bitmap, unsigned long bit) { - unsigned k; + unsigned int n; - while (swp) { - for (k = 0; k < MAP_PAGE_SIZE; k++) - if (swp->entries[k].val) - swap_free(swp->entries[k]); - swp = swp->next; + n = BITMAP_PAGE_BITS; + while (bitmap && n <= bit) { + n += BITMAP_PAGE_BITS; + bitmap = bitmap->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; + 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; } -/** - * save_image_data - save the data pages pointed to by the PBEs - * from the list @pblist using the swap map handle @handle - * (assume there are @nr_pages data pages to save) - */ - -static int save_image_data(struct pbe *pblist, - struct swap_map_handle *handle, - unsigned int nr_pages) -{ - unsigned int m; - struct pbe *p; - int error = 0; - - printk("Saving image data pages (%u pages) ... ", nr_pages); - m = nr_pages / 100; - if (!m) - m = 1; - nr_pages = 0; - for_each_pbe (p, pblist) { - error = swap_map_write_page(handle, p->address); - if (error) - break; - if (!(nr_pages % m)) - printk("\b\b\b\b%3d%%", nr_pages / m); - nr_pages++; - } - if (!error) - printk("\b\b\b\bdone\n"); - return error; -} - -static void dump_info(void) -{ - pr_debug(" swsusp: Version: %u\n",swsusp_info.version_code); - pr_debug(" swsusp: Num Pages: %ld\n",swsusp_info.num_physpages); - pr_debug(" swsusp: UTS Sys: %s\n",swsusp_info.uts.sysname); - pr_debug(" swsusp: UTS Node: %s\n",swsusp_info.uts.nodename); - pr_debug(" swsusp: UTS Release: %s\n",swsusp_info.uts.release); - pr_debug(" swsusp: UTS Version: %s\n",swsusp_info.uts.version); - pr_debug(" swsusp: UTS Machine: %s\n",swsusp_info.uts.machine); - pr_debug(" swsusp: UTS Domain: %s\n",swsusp_info.uts.domainname); - pr_debug(" swsusp: CPUs: %d\n",swsusp_info.cpus); - pr_debug(" swsusp: Image: %ld Pages\n",swsusp_info.image_pages); - pr_debug(" swsusp: Total: %ld Pages\n", swsusp_info.pages); -} - -static void init_header(unsigned int nr_pages) -{ - memset(&swsusp_info, 0, sizeof(swsusp_info)); - swsusp_info.version_code = LINUX_VERSION_CODE; - swsusp_info.num_physpages = num_physpages; - memcpy(&swsusp_info.uts, &system_utsname, sizeof(system_utsname)); - - swsusp_info.cpus = num_online_cpus(); - swsusp_info.image_pages = nr_pages; - swsusp_info.pages = nr_pages + - ((nr_pages * sizeof(long) + PAGE_SIZE - 1) >> PAGE_SHIFT) + 1; -} - -/** - * pack_orig_addresses - the .orig_address fields of the PBEs from the - * list starting at @pbe are stored in the array @buf[] (1 page) - */ - -static inline struct pbe *pack_orig_addresses(unsigned long *buf, - struct pbe *pbe) -{ - 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 alloc_swap_page(int swap, struct bitmap_page *bitmap) { - unsigned long *buf; - unsigned int n = 0; - struct pbe *p; - int error = 0; + unsigned long offset; - 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++; + offset = swp_offset(get_swap_page_of_type(swap)); + if (offset) { + if (bitmap_set(bitmap, offset)) { + swap_free(swp_entry(swap, offset)); + offset = 0; + } } - free_page((unsigned long)buf); - if (!error) - printk("done (%u pages saved)\n", n); - return error; + return offset; } -/** - * 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 from the resume partition. - */ - -static int enough_swap(unsigned int nr_pages) +void free_all_swap_pages(int swap, struct bitmap_page *bitmap) { - unsigned int free_swap = swap_info[root_swap].pages - - swap_info[root_swap].inuse_pages; - - 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); -} + unsigned int bit, n; + unsigned long test; -/** - * swsusp_write - Write entire image and metadata. - * - * It is important _NOT_ to umount filesystems at this point. We want - * them synced (in case something goes wrong) but we DO not want to mark - * filesystem clean: it is not. (And it does not matter, if we resume - * correctly, we'll mark system clean, anyway.) - */ - -int swsusp_write(struct pbe *pblist, unsigned int nr_pages) -{ - struct swap_map_page *swap_map; - struct swap_map_handle handle; - swp_entry_t start; - int error; - - if ((error = swsusp_swap_check())) { - printk(KERN_ERR "swsusp: Cannot find swap device, try swapon -a.\n"); - return error; - } - if (!enough_swap(nr_pages)) { - printk(KERN_ERR "swsusp: Not enough free swap\n"); - return -ENOSPC; + 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; } - - init_header(nr_pages); - swap_map = alloc_swap_map(swsusp_info.pages); - if (!swap_map) - return -ENOMEM; - init_swap_map_handle(&handle, swap_map); - - error = swap_map_write_page(&handle, (unsigned long)&swsusp_info); - if (!error) - error = save_image_metadata(pblist, &handle); - if (!error) - error = save_image_data(pblist, &handle, nr_pages); - if (error) - goto Free_image_entries; - - swap_map = reverse_swap_map(swap_map); - error = save_swap_map(swap_map, &start); - if (error) - goto Free_map_entries; - - dump_info(); - printk( "S" ); - error = mark_swapfiles(start); - printk( "|\n" ); - if (error) - goto Free_map_entries; - -Free_swap_map: - free_swap_map(swap_map); - return error; - -Free_map_entries: - free_swap_map_entries(swap_map); -Free_image_entries: - free_image_entries(swap_map); - goto Free_swap_map; } /** @@ -660,379 +271,3 @@ int swsusp_resume(void) local_irq_enable(); return error; } - -/** - * mark_unsafe_pages - mark the pages that cannot be used for storing - * the image during resume, because they conflict with the pages that - * had been used before suspend - */ - -static void mark_unsafe_pages(struct pbe *pblist) -{ - struct zone *zone; - unsigned long zone_pfn; - struct pbe *p; - - if (!pblist) /* a sanity check */ - return; - - /* Clear page flags */ - for_each_zone (zone) { - for (zone_pfn = 0; zone_pfn < zone->spanned_pages; ++zone_pfn) - if (pfn_valid(zone_pfn + zone->zone_start_pfn)) - ClearPageNosaveFree(pfn_to_page(zone_pfn + - zone->zone_start_pfn)); - } - - /* Mark orig addresses */ - for_each_pbe (p, pblist) - SetPageNosaveFree(virt_to_page(p->orig_address)); - -} - -static void copy_page_backup_list(struct pbe *dst, struct pbe *src) -{ - /* We assume both lists contain the same number of elements */ - while (src) { - dst->orig_address = src->orig_address; - dst = dst->next; - src = src->next; - } -} - -/* - * Using bio to read from swap. - * This code requires a bit more work than just using buffer heads - * but, it is the recommended way for 2.5/2.6. - * The following are to signal the beginning and end of I/O. Bios - * finish asynchronously, while we want them to happen synchronously. - * A simple atomic_t, and a wait loop take care of this problem. - */ - -static atomic_t io_done = ATOMIC_INIT(0); - -static int end_io(struct bio *bio, unsigned int num, int err) -{ - if (!test_bit(BIO_UPTODATE, &bio->bi_flags)) - panic("I/O error reading memory image"); - atomic_set(&io_done, 0); - return 0; -} - -static struct block_device *resume_bdev; - -/** - * submit - submit BIO request. - * @rw: READ or WRITE. - * @off physical offset of page. - * @page: page we're reading or writing. - * - * Straight from the textbook - allocate and initialize the bio. - * If we're writing, make sure the page is marked as dirty. - * Then submit it and wait. - */ - -static int submit(int rw, pgoff_t page_off, void *page) -{ - int error = 0; - struct bio *bio; - - bio = bio_alloc(GFP_ATOMIC, 1); - if (!bio) - return -ENOMEM; - bio->bi_sector = page_off * (PAGE_SIZE >> 9); - bio->bi_bdev = resume_bdev; - bio->bi_end_io = end_io; - - if (bio_add_page(bio, virt_to_page(page), PAGE_SIZE, 0) < PAGE_SIZE) { - printk("swsusp: ERROR: adding page to bio at %ld\n",page_off); - error = -EFAULT; - goto Done; - } - - - atomic_set(&io_done, 1); - submit_bio(rw | (1 << BIO_RW_SYNC), bio); - while (atomic_read(&io_done)) - yield(); - if (rw == READ) - bio_set_pages_dirty(bio); - Done: - bio_put(bio); - return error; -} - -static int bio_read_page(pgoff_t page_off, void *page) -{ - return submit(READ, page_off, page); -} - -static int bio_write_page(pgoff_t page_off, void *page) -{ - return submit(WRITE, page_off, page); -} - -/** - * The following functions allow us to read data using a swap map - * in a file-alike way - */ - -static inline void release_swap_map_reader(struct swap_map_handle *handle) -{ - if (handle->cur) - free_page((unsigned long)handle->cur); - handle->cur = NULL; -} - -static inline int get_swap_map_reader(struct swap_map_handle *handle, - swp_entry_t start) -{ - int error; - - if (!swp_offset(start)) - return -EINVAL; - handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_ATOMIC); - if (!handle->cur) - return -ENOMEM; - error = bio_read_page(swp_offset(start), handle->cur); - if (error) { - release_swap_map_reader(handle); - return error; - } - handle->k = 0; - return 0; -} - -static inline int swap_map_read_page(struct swap_map_handle *handle, void *buf) -{ - unsigned long offset; - int error; - - if (!handle->cur) - return -EINVAL; - offset = swp_offset(handle->cur->entries[handle->k]); - if (!offset) - return -EINVAL; - error = bio_read_page(offset, buf); - if (error) - return error; - if (++handle->k >= MAP_PAGE_SIZE) { - handle->k = 0; - offset = swp_offset(handle->cur->next_swap); - if (!offset) - release_swap_map_reader(handle); - else - error = bio_read_page(offset, handle->cur); - } - return error; -} - -static int check_header(void) -{ - char *reason = NULL; - - dump_info(); - if (swsusp_info.version_code != LINUX_VERSION_CODE) - reason = "kernel version"; - if (swsusp_info.num_physpages != num_physpages) - reason = "memory size"; - if (strcmp(swsusp_info.uts.sysname,system_utsname.sysname)) - reason = "system type"; - if (strcmp(swsusp_info.uts.release,system_utsname.release)) - reason = "kernel release"; - if (strcmp(swsusp_info.uts.version,system_utsname.version)) - reason = "version"; - if (strcmp(swsusp_info.uts.machine,system_utsname.machine)) - reason = "machine"; - if (reason) { - printk(KERN_ERR "swsusp: Resume mismatch: %s\n", reason); - return -EPERM; - } - return 0; -} - -/** - * load_image_data - load the image data using the swap map handle - * @handle and store them using the page backup list @pblist - * (assume there are @nr_pages pages to load) - */ - -static int load_image_data(struct pbe *pblist, - struct swap_map_handle *handle, - unsigned int nr_pages) -{ - int error; - unsigned int m; - struct pbe *p; - - if (!pblist) - return -EINVAL; - printk("Loading image data pages (%u pages) ... ", nr_pages); - m = nr_pages / 100; - if (!m) - m = 1; - nr_pages = 0; - p = pblist; - while (p) { - error = swap_map_read_page(handle, (void *)p->address); - if (error) - break; - p = p->next; - if (!(nr_pages % m)) - printk("\b\b\b\b%3d%%", nr_pages / m); - nr_pages++; - } - if (!error) - printk("\b\b\b\bdone\n"); - return error; -} - -/** - * unpack_orig_addresses - copy the elements of @buf[] (1 page) to - * the PBEs in the list starting at @pbe - */ - -static inline struct pbe *unpack_orig_addresses(unsigned long *buf, - struct pbe *pbe) -{ - int j; - - for (j = 0; j < PAGE_SIZE / sizeof(long) && pbe; j++) { - pbe->orig_address = buf[j]; - pbe = pbe->next; - } - return pbe; -} - -/** - * load_image_metadata - load the image metadata using the swap map - * handle @handle and put them into the PBEs in the list @pblist - */ - -static int load_image_metadata(struct pbe *pblist, struct swap_map_handle *handle) -{ - struct pbe *p; - unsigned long *buf; - unsigned int n = 0; - int error = 0; - - printk("Loading image metadata ... "); - buf = (unsigned long *)get_zeroed_page(GFP_ATOMIC); - if (!buf) - return -ENOMEM; - p = pblist; - while (p) { - error = swap_map_read_page(handle, buf); - if (error) - break; - p = unpack_orig_addresses(buf, p); - n++; - } - free_page((unsigned long)buf); - if (!error) - printk("done (%u pages loaded)\n", n); - return error; -} - -int swsusp_read(struct pbe **pblist_ptr) -{ - int error; - struct pbe *p, *pblist; - struct swap_map_handle handle; - unsigned int nr_pages; - - if (IS_ERR(resume_bdev)) { - pr_debug("swsusp: block device not initialised\n"); - return PTR_ERR(resume_bdev); - } - - error = get_swap_map_reader(&handle, swsusp_header.image); - if (!error) - error = swap_map_read_page(&handle, &swsusp_info); - if (!error) - error = check_header(); - if (error) - return error; - nr_pages = swsusp_info.image_pages; - p = alloc_pagedir(nr_pages, GFP_ATOMIC, 0); - if (!p) - return -ENOMEM; - error = load_image_metadata(p, &handle); - if (!error) { - mark_unsafe_pages(p); - pblist = alloc_pagedir(nr_pages, GFP_ATOMIC, 1); - if (pblist) - copy_page_backup_list(pblist, p); - free_pagedir(p); - if (!pblist) - error = -ENOMEM; - - /* Allocate memory for the image and read the data from swap */ - if (!error) - error = alloc_data_pages(pblist, GFP_ATOMIC, 1); - if (!error) { - release_eaten_pages(); - error = load_image_data(pblist, &handle, nr_pages); - } - if (!error) - *pblist_ptr = pblist; - } - release_swap_map_reader(&handle); - - blkdev_put(resume_bdev); - - if (!error) - pr_debug("swsusp: Reading resume file was successful\n"); - else - pr_debug("swsusp: Error %d resuming\n", error); - return error; -} - -/** - * swsusp_check - Check for swsusp signature in the resume device - */ - -int swsusp_check(void) -{ - int error; - - resume_bdev = open_by_devnum(swsusp_resume_device, FMODE_READ); - if (!IS_ERR(resume_bdev)) { - set_blocksize(resume_bdev, PAGE_SIZE); - memset(&swsusp_header, 0, sizeof(swsusp_header)); - if ((error = bio_read_page(0, &swsusp_header))) - return error; - if (!memcmp(SWSUSP_SIG, swsusp_header.sig, 10)) { - memcpy(swsusp_header.sig, swsusp_header.orig_sig, 10); - /* Reset swap signature now */ - error = bio_write_page(0, &swsusp_header); - } else { - return -EINVAL; - } - if (error) - blkdev_put(resume_bdev); - else - pr_debug("swsusp: Signature found, resuming\n"); - } else { - error = PTR_ERR(resume_bdev); - } - - if (error) - pr_debug("swsusp: Error %d check for resume file\n", error); - - return error; -} - -/** - * swsusp_close - close swap device. - */ - -void swsusp_close(void) -{ - if (IS_ERR(resume_bdev)) { - pr_debug("swsusp: block device not initialised\n"); - return; - } - - blkdev_put(resume_bdev); -} |