| /* |
| * linux/kernel/power/swap.c |
| * |
| * This file provides functions for reading the suspend image from |
| * and writing it to a swap partition. |
| * |
| * Copyright (C) 1998,2001-2005 Pavel Machek <pavel@ucw.cz> |
| * Copyright (C) 2006 Rafael J. Wysocki <rjw@sisk.pl> |
| * Copyright (C) 2010-2012 Bojan Smojver <bojan@rexursive.com> |
| * |
| * This file is released under the GPLv2. |
| * |
| */ |
| |
| #include <linux/module.h> |
| #include <linux/file.h> |
| #include <linux/delay.h> |
| #include <linux/bitops.h> |
| #include <linux/genhd.h> |
| #include <linux/device.h> |
| #include <linux/buffer_head.h> |
| #include <linux/bio.h> |
| #include <linux/blkdev.h> |
| #include <linux/swap.h> |
| #include <linux/swapops.h> |
| #include <linux/pm.h> |
| #include <linux/slab.h> |
| #include <linux/lzo.h> |
| #include <linux/vmalloc.h> |
| #include <linux/cpumask.h> |
| #include <linux/atomic.h> |
| #include <linux/kthread.h> |
| #include <linux/crc32.h> |
| |
| #include "power.h" |
| |
| #define HIBERNATE_SIG "S1SUSPEND" |
| |
| /* |
| * 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_ENTRIES 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 pick up all swap_map_page structures into a list. |
| */ |
| |
| #define MAP_PAGE_ENTRIES (PAGE_SIZE / sizeof(sector_t) - 1) |
| |
| /* |
| * Number of free pages that are not high. |
| */ |
| static inline unsigned long low_free_pages(void) |
| { |
| return nr_free_pages() - nr_free_highpages(); |
| } |
| |
| /* |
| * Number of pages required to be kept free while writing the image. Always |
| * half of all available low pages before the writing starts. |
| */ |
| static inline unsigned long reqd_free_pages(void) |
| { |
| return low_free_pages() / 2; |
| } |
| |
| struct swap_map_page { |
| sector_t entries[MAP_PAGE_ENTRIES]; |
| sector_t next_swap; |
| }; |
| |
| struct swap_map_page_list { |
| struct swap_map_page *map; |
| struct swap_map_page_list *next; |
| }; |
| |
| /** |
| * The swap_map_handle structure is used for handling swap in |
| * a file-alike way |
| */ |
| |
| struct swap_map_handle { |
| struct swap_map_page *cur; |
| struct swap_map_page_list *maps; |
| sector_t cur_swap; |
| sector_t first_sector; |
| unsigned int k; |
| unsigned long reqd_free_pages; |
| u32 crc32; |
| }; |
| |
| struct swsusp_header { |
| char reserved[PAGE_SIZE - 20 - sizeof(sector_t) - sizeof(int) - |
| sizeof(u32)]; |
| u32 crc32; |
| sector_t image; |
| unsigned int flags; /* Flags to pass to the "boot" kernel */ |
| char orig_sig[10]; |
| char sig[10]; |
| } __attribute__((packed)); |
| |
| static struct swsusp_header *swsusp_header; |
| |
| /** |
| * The following functions are used for tracing the allocated |
| * swap pages, so that they can be freed in case of an error. |
| */ |
| |
| struct swsusp_extent { |
| struct rb_node node; |
| unsigned long start; |
| unsigned long end; |
| }; |
| |
| static struct rb_root swsusp_extents = RB_ROOT; |
| |
| static int swsusp_extents_insert(unsigned long swap_offset) |
| { |
| struct rb_node **new = &(swsusp_extents.rb_node); |
| struct rb_node *parent = NULL; |
| struct swsusp_extent *ext; |
| |
| /* Figure out where to put the new node */ |
| while (*new) { |
| ext = container_of(*new, struct swsusp_extent, node); |
| parent = *new; |
| if (swap_offset < ext->start) { |
| /* Try to merge */ |
| if (swap_offset == ext->start - 1) { |
| ext->start--; |
| return 0; |
| } |
| new = &((*new)->rb_left); |
| } else if (swap_offset > ext->end) { |
| /* Try to merge */ |
| if (swap_offset == ext->end + 1) { |
| ext->end++; |
| return 0; |
| } |
| new = &((*new)->rb_right); |
| } else { |
| /* It already is in the tree */ |
| return -EINVAL; |
| } |
| } |
| /* Add the new node and rebalance the tree. */ |
| ext = kzalloc(sizeof(struct swsusp_extent), GFP_KERNEL); |
| if (!ext) |
| return -ENOMEM; |
| |
| ext->start = swap_offset; |
| ext->end = swap_offset; |
| rb_link_node(&ext->node, parent, new); |
| rb_insert_color(&ext->node, &swsusp_extents); |
| return 0; |
| } |
| |
| /** |
| * alloc_swapdev_block - allocate a swap page and register that it has |
| * been allocated, so that it can be freed in case of an error. |
| */ |
| |
| sector_t alloc_swapdev_block(int swap) |
| { |
| unsigned long offset; |
| |
| offset = swp_offset(get_swap_page_of_type(swap)); |
| if (offset) { |
| if (swsusp_extents_insert(offset)) |
| swap_free(swp_entry(swap, offset)); |
| else |
| return swapdev_block(swap, offset); |
| } |
| return 0; |
| } |
| |
| /** |
| * free_all_swap_pages - free swap pages allocated for saving image data. |
| * It also frees the extents used to register which swap entries had been |
| * allocated. |
| */ |
| |
| void free_all_swap_pages(int swap) |
| { |
| struct rb_node *node; |
| |
| while ((node = swsusp_extents.rb_node)) { |
| struct swsusp_extent *ext; |
| unsigned long offset; |
| |
| ext = container_of(node, struct swsusp_extent, node); |
| rb_erase(node, &swsusp_extents); |
| for (offset = ext->start; offset <= ext->end; offset++) |
| swap_free(swp_entry(swap, offset)); |
| |
| kfree(ext); |
| } |
| } |
| |
| int swsusp_swap_in_use(void) |
| { |
| return (swsusp_extents.rb_node != NULL); |
| } |
| |
| /* |
| * General things |
| */ |
| |
| static unsigned short root_swap = 0xffff; |
| struct block_device *hib_resume_bdev; |
| |
| /* |
| * Saving part |
| */ |
| |
| static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags) |
| { |
| int error; |
| |
| hib_bio_read_page(swsusp_resume_block, swsusp_header, NULL); |
| 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, HIBERNATE_SIG, 10); |
| swsusp_header->image = handle->first_sector; |
| swsusp_header->flags = flags; |
| if (flags & SF_CRC32_MODE) |
| swsusp_header->crc32 = handle->crc32; |
| error = hib_bio_write_page(swsusp_resume_block, |
| swsusp_header, NULL); |
| } else { |
| printk(KERN_ERR "PM: Swap header not found!\n"); |
| error = -ENODEV; |
| } |
| return error; |
| } |
| |
| /** |
| * swsusp_swap_check - check if the resume device is a swap device |
| * and get its index (if so) |
| * |
| * This is called before saving image |
| */ |
| static int swsusp_swap_check(void) |
| { |
| int res; |
| |
| res = swap_type_of(swsusp_resume_device, swsusp_resume_block, |
| &hib_resume_bdev); |
| if (res < 0) |
| return res; |
| |
| root_swap = res; |
| res = blkdev_get(hib_resume_bdev, FMODE_WRITE, NULL); |
| if (res) |
| return res; |
| |
| res = set_blocksize(hib_resume_bdev, PAGE_SIZE); |
| if (res < 0) |
| blkdev_put(hib_resume_bdev, FMODE_WRITE); |
| |
| return res; |
| } |
| |
| /** |
| * write_page - Write one page to given swap location. |
| * @buf: Address we're writing. |
| * @offset: Offset of the swap page we're writing to. |
| * @bio_chain: Link the next write BIO here |
| */ |
| |
| static int write_page(void *buf, sector_t offset, struct bio **bio_chain) |
| { |
| void *src; |
| int ret; |
| |
| if (!offset) |
| return -ENOSPC; |
| |
| if (bio_chain) { |
| src = (void *)__get_free_page(__GFP_WAIT | __GFP_NOWARN | |
| __GFP_NORETRY); |
| if (src) { |
| copy_page(src, buf); |
| } else { |
| ret = hib_wait_on_bio_chain(bio_chain); /* Free pages */ |
| if (ret) |
| return ret; |
| src = (void *)__get_free_page(__GFP_WAIT | |
| __GFP_NOWARN | |
| __GFP_NORETRY); |
| if (src) { |
| copy_page(src, buf); |
| } else { |
| WARN_ON_ONCE(1); |
| bio_chain = NULL; /* Go synchronous */ |
| src = buf; |
| } |
| } |
| } else { |
| src = buf; |
| } |
| return hib_bio_write_page(offset, src, bio_chain); |
| } |
| |
| static void release_swap_writer(struct swap_map_handle *handle) |
| { |
| if (handle->cur) |
| free_page((unsigned long)handle->cur); |
| handle->cur = NULL; |
| } |
| |
| static int get_swap_writer(struct swap_map_handle *handle) |
| { |
| int ret; |
| |
| ret = swsusp_swap_check(); |
| if (ret) { |
| if (ret != -ENOSPC) |
| printk(KERN_ERR "PM: Cannot find swap device, try " |
| "swapon -a.\n"); |
| return ret; |
| } |
| handle->cur = (struct swap_map_page *)get_zeroed_page(GFP_KERNEL); |
| if (!handle->cur) { |
| ret = -ENOMEM; |
| goto err_close; |
| } |
| handle->cur_swap = alloc_swapdev_block(root_swap); |
| if (!handle->cur_swap) { |
| ret = -ENOSPC; |
| goto err_rel; |
| } |
| handle->k = 0; |
| handle->reqd_free_pages = reqd_free_pages(); |
| handle->first_sector = handle->cur_swap; |
| return 0; |
| err_rel: |
| release_swap_writer(handle); |
| err_close: |
| swsusp_close(FMODE_WRITE); |
| return ret; |
| } |
| |
| static int swap_write_page(struct swap_map_handle *handle, void *buf, |
| struct bio **bio_chain) |
| { |
| int error = 0; |
| sector_t offset; |
| |
| if (!handle->cur) |
| return -EINVAL; |
| offset = alloc_swapdev_block(root_swap); |
| error = write_page(buf, offset, bio_chain); |
| if (error) |
| return error; |
| handle->cur->entries[handle->k++] = offset; |
| if (handle->k >= MAP_PAGE_ENTRIES) { |
| offset = alloc_swapdev_block(root_swap); |
| if (!offset) |
| return -ENOSPC; |
| handle->cur->next_swap = offset; |
| error = write_page(handle->cur, handle->cur_swap, bio_chain); |
| if (error) |
| goto out; |
| clear_page(handle->cur); |
| handle->cur_swap = offset; |
| handle->k = 0; |
| |
| if (bio_chain && low_free_pages() <= handle->reqd_free_pages) { |
| error = hib_wait_on_bio_chain(bio_chain); |
| if (error) |
| goto out; |
| /* |
| * Recalculate the number of required free pages, to |
| * make sure we never take more than half. |
| */ |
| handle->reqd_free_pages = reqd_free_pages(); |
| } |
| } |
| out: |
| return error; |
| } |
| |
| static int flush_swap_writer(struct swap_map_handle *handle) |
| { |
| if (handle->cur && handle->cur_swap) |
| return write_page(handle->cur, handle->cur_swap, NULL); |
| else |
| return -EINVAL; |
| } |
| |
| static int swap_writer_finish(struct swap_map_handle *handle, |
| unsigned int flags, int error) |
| { |
| if (!error) { |
| flush_swap_writer(handle); |
| printk(KERN_INFO "PM: S"); |
| error = mark_swapfiles(handle, flags); |
| printk("|\n"); |
| } |
| |
| if (error) |
| free_all_swap_pages(root_swap); |
| release_swap_writer(handle); |
| swsusp_close(FMODE_WRITE); |
| |
| return error; |
| } |
| |
| /* We need to remember how much compressed data we need to read. */ |
| #define LZO_HEADER sizeof(size_t) |
| |
| /* Number of pages/bytes we'll compress at one time. */ |
| #define LZO_UNC_PAGES 32 |
| #define LZO_UNC_SIZE (LZO_UNC_PAGES * PAGE_SIZE) |
| |
| /* Number of pages/bytes we need for compressed data (worst case). */ |
| #define LZO_CMP_PAGES DIV_ROUND_UP(lzo1x_worst_compress(LZO_UNC_SIZE) + \ |
| LZO_HEADER, PAGE_SIZE) |
| #define LZO_CMP_SIZE (LZO_CMP_PAGES * PAGE_SIZE) |
| |
| /* Maximum number of threads for compression/decompression. */ |
| #define LZO_THREADS 3 |
| |
| /* Minimum/maximum number of pages for read buffering. */ |
| #define LZO_MIN_RD_PAGES 1024 |
| #define LZO_MAX_RD_PAGES 8192 |
| |
| |
| /** |
| * save_image - save the suspend image data |
| */ |
| |
| static int save_image(struct swap_map_handle *handle, |
| struct snapshot_handle *snapshot, |
| unsigned int nr_to_write) |
| { |
| unsigned int m; |
| int ret; |
| int nr_pages; |
| int err2; |
| struct bio *bio; |
| struct timeval start; |
| struct timeval stop; |
| |
| printk(KERN_INFO "PM: Saving image data pages (%u pages) ... ", |
| nr_to_write); |
| m = nr_to_write / 100; |
| if (!m) |
| m = 1; |
| nr_pages = 0; |
| bio = NULL; |
| do_gettimeofday(&start); |
| while (1) { |
| ret = snapshot_read_next(snapshot); |
| if (ret <= 0) |
| break; |
| ret = swap_write_page(handle, data_of(*snapshot), &bio); |
| if (ret) |
| break; |
| if (!(nr_pages % m)) |
| printk(KERN_CONT "\b\b\b\b%3d%%", nr_pages / m); |
| nr_pages++; |
| } |
| err2 = hib_wait_on_bio_chain(&bio); |
| do_gettimeofday(&stop); |
| if (!ret) |
| ret = err2; |
| if (!ret) |
| printk(KERN_CONT "\b\b\b\bdone\n"); |
| else |
| printk(KERN_CONT "\n"); |
| swsusp_show_speed(&start, &stop, nr_to_write, "Wrote"); |
| return ret; |
| } |
| |
| /** |
| * Structure used for CRC32. |
| */ |
| struct crc_data { |
| struct task_struct *thr; /* thread */ |
| atomic_t ready; /* ready to start flag */ |
| atomic_t stop; /* ready to stop flag */ |
| unsigned run_threads; /* nr current threads */ |
| wait_queue_head_t go; /* start crc update */ |
| wait_queue_head_t done; /* crc update done */ |
| u32 *crc32; /* points to handle's crc32 */ |
| size_t *unc_len[LZO_THREADS]; /* uncompressed lengths */ |
| unsigned char *unc[LZO_THREADS]; /* uncompressed data */ |
| }; |
| |
| /** |
| * CRC32 update function that runs in its own thread. |
| */ |
| static int crc32_threadfn(void *data) |
| { |
| struct crc_data *d = data; |
| unsigned i; |
| |
| while (1) { |
| wait_event(d->go, atomic_read(&d->ready) || |
| kthread_should_stop()); |
| if (kthread_should_stop()) { |
| d->thr = NULL; |
| atomic_set(&d->stop, 1); |
| wake_up(&d->done); |
| break; |
| } |
| atomic_set(&d->ready, 0); |
| |
| for (i = 0; i < d->run_threads; i++) |
| *d->crc32 = crc32_le(*d->crc32, |
| d->unc[i], *d->unc_len[i]); |
| atomic_set(&d->stop, 1); |
| wake_up(&d->done); |
| } |
| return 0; |
| } |
| /** |
| * Structure used for LZO data compression. |
| */ |
| struct cmp_data { |
| struct task_struct *thr; /* thread */ |
| atomic_t ready; /* ready to start flag */ |
| atomic_t stop; /* ready to stop flag */ |
| int ret; /* return code */ |
| wait_queue_head_t go; /* start compression */ |
| wait_queue_head_t done; /* compression done */ |
| size_t unc_len; /* uncompressed length */ |
| size_t cmp_len; /* compressed length */ |
| unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */ |
| unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */ |
| unsigned char wrk[LZO1X_1_MEM_COMPRESS]; /* compression workspace */ |
| }; |
| |
| /** |
| * Compression function that runs in its own thread. |
| */ |
| static int lzo_compress_threadfn(void *data) |
| { |
| struct cmp_data *d = data; |
| |
| while (1) { |
| wait_event(d->go, atomic_read(&d->ready) || |
| kthread_should_stop()); |
| if (kthread_should_stop()) { |
| d->thr = NULL; |
| d->ret = -1; |
| atomic_set(&d->stop, 1); |
| wake_up(&d->done); |
| break; |
| } |
| atomic_set(&d->ready, 0); |
| |
| d->ret = lzo1x_1_compress(d->unc, d->unc_len, |
| d->cmp + LZO_HEADER, &d->cmp_len, |
| d->wrk); |
| atomic_set(&d->stop, 1); |
| wake_up(&d->done); |
| } |
| return 0; |
| } |
| |
| /** |
| * save_image_lzo - Save the suspend image data compressed with LZO. |
| * @handle: Swap mam handle to use for saving the image. |
| * @snapshot: Image to read data from. |
| * @nr_to_write: Number of pages to save. |
| */ |
| static int save_image_lzo(struct swap_map_handle *handle, |
| struct snapshot_handle *snapshot, |
| unsigned int nr_to_write) |
| { |
| unsigned int m; |
| int ret = 0; |
| int nr_pages; |
| int err2; |
| struct bio *bio; |
| struct timeval start; |
| struct timeval stop; |
| size_t off; |
| unsigned thr, run_threads, nr_threads; |
| unsigned char *page = NULL; |
| struct cmp_data *data = NULL; |
| struct crc_data *crc = NULL; |
| |
| /* |
| * We'll limit the number of threads for compression to limit memory |
| * footprint. |
| */ |
| nr_threads = num_online_cpus() - 1; |
| nr_threads = clamp_val(nr_threads, 1, LZO_THREADS); |
| |
| page = (void *)__get_free_page(__GFP_WAIT | __GFP_HIGH); |
| if (!page) { |
| printk(KERN_ERR "PM: Failed to allocate LZO page\n"); |
| ret = -ENOMEM; |
| goto out_clean; |
| } |
| |
| data = vmalloc(sizeof(*data) * nr_threads); |
| if (!data) { |
| printk(KERN_ERR "PM: Failed to allocate LZO data\n"); |
| ret = -ENOMEM; |
| goto out_clean; |
| } |
| for (thr = 0; thr < nr_threads; thr++) |
| memset(&data[thr], 0, offsetof(struct cmp_data, go)); |
| |
| crc = kmalloc(sizeof(*crc), GFP_KERNEL); |
| if (!crc) { |
| printk(KERN_ERR "PM: Failed to allocate crc\n"); |
| ret = -ENOMEM; |
| goto out_clean; |
| } |
| memset(crc, 0, offsetof(struct crc_data, go)); |
| |
| /* |
| * Start the compression threads. |
| */ |
| for (thr = 0; thr < nr_threads; thr++) { |
| init_waitqueue_head(&data[thr].go); |
| init_waitqueue_head(&data[thr].done); |
| |
| data[thr].thr = kthread_run(lzo_compress_threadfn, |
| &data[thr], |
| "image_compress/%u", thr); |
| if (IS_ERR(data[thr].thr)) { |
| data[thr].thr = NULL; |
| printk(KERN_ERR |
| "PM: Cannot start compression threads\n"); |
| ret = -ENOMEM; |
| goto out_clean; |
| } |
| } |
| |
| /* |
| * Start the CRC32 thread. |
| */ |
| init_waitqueue_head(&crc->go); |
| init_waitqueue_head(&crc->done); |
| |
| handle->crc32 = 0; |
| crc->crc32 = &handle->crc32; |
| for (thr = 0; thr < nr_threads; thr++) { |
| crc->unc[thr] = data[thr].unc; |
| crc->unc_len[thr] = &data[thr].unc_len; |
| } |
| |
| crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32"); |
| if (IS_ERR(crc->thr)) { |
| crc->thr = NULL; |
| printk(KERN_ERR "PM: Cannot start CRC32 thread\n"); |
| ret = -ENOMEM; |
| goto out_clean; |
| } |
| |
| /* |
| * Adjust the number of required free pages after all allocations have |
| * been done. We don't want to run out of pages when writing. |
| */ |
| handle->reqd_free_pages = reqd_free_pages(); |
| |
| printk(KERN_INFO |
| "PM: Using %u thread(s) for compression.\n" |
| "PM: Compressing and saving image data (%u pages) ... ", |
| nr_threads, nr_to_write); |
| m = nr_to_write / 100; |
| if (!m) |
| m = 1; |
| nr_pages = 0; |
| bio = NULL; |
| do_gettimeofday(&start); |
| for (;;) { |
| for (thr = 0; thr < nr_threads; thr++) { |
| for (off = 0; off < LZO_UNC_SIZE; off += PAGE_SIZE) { |
| ret = snapshot_read_next(snapshot); |
| if (ret < 0) |
| goto out_finish; |
| |
| if (!ret) |
| break; |
| |
| memcpy(data[thr].unc + off, |
| data_of(*snapshot), PAGE_SIZE); |
| |
| if (!(nr_pages % m)) |
| printk(KERN_CONT "\b\b\b\b%3d%%", |
| nr_pages / m); |
| nr_pages++; |
| } |
| if (!off) |
| break; |
| |
| data[thr].unc_len = off; |
| |
| atomic_set(&data[thr].ready, 1); |
| wake_up(&data[thr].go); |
| } |
| |
| if (!thr) |
| break; |
| |
| crc->run_threads = thr; |
| atomic_set(&crc->ready, 1); |
| wake_up(&crc->go); |
| |
| for (run_threads = thr, thr = 0; thr < run_threads; thr++) { |
| wait_event(data[thr].done, |
| atomic_read(&data[thr].stop)); |
| atomic_set(&data[thr].stop, 0); |
| |
| ret = data[thr].ret; |
| |
| if (ret < 0) { |
| printk(KERN_ERR "PM: LZO compression failed\n"); |
| goto out_finish; |
| } |
| |
| if (unlikely(!data[thr].cmp_len || |
| data[thr].cmp_len > |
| lzo1x_worst_compress(data[thr].unc_len))) { |
| printk(KERN_ERR |
| "PM: Invalid LZO compressed length\n"); |
| ret = -1; |
| goto out_finish; |
| } |
| |
| *(size_t *)data[thr].cmp = data[thr].cmp_len; |
| |
| /* |
| * Given we are writing one page at a time to disk, we |
| * copy that much from the buffer, although the last |
| * bit will likely be smaller than full page. This is |
| * OK - we saved the length of the compressed data, so |
| * any garbage at the end will be discarded when we |
| * read it. |
| */ |
| for (off = 0; |
| off < LZO_HEADER + data[thr].cmp_len; |
| off += PAGE_SIZE) { |
| memcpy(page, data[thr].cmp + off, PAGE_SIZE); |
| |
| ret = swap_write_page(handle, page, &bio); |
| if (ret) |
| goto out_finish; |
| } |
| } |
| |
| wait_event(crc->done, atomic_read(&crc->stop)); |
| atomic_set(&crc->stop, 0); |
| } |
| |
| out_finish: |
| err2 = hib_wait_on_bio_chain(&bio); |
| do_gettimeofday(&stop); |
| if (!ret) |
| ret = err2; |
| if (!ret) { |
| printk(KERN_CONT "\b\b\b\bdone\n"); |
| } else { |
| printk(KERN_CONT "\n"); |
| } |
| swsusp_show_speed(&start, &stop, nr_to_write, "Wrote"); |
| out_clean: |
| if (crc) { |
| if (crc->thr) |
| kthread_stop(crc->thr); |
| kfree(crc); |
| } |
| if (data) { |
| for (thr = 0; thr < nr_threads; thr++) |
| if (data[thr].thr) |
| kthread_stop(data[thr].thr); |
| vfree(data); |
| } |
| if (page) free_page((unsigned long)page); |
| |
| return ret; |
| } |
| |
| /** |
| * 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, unsigned int flags) |
| { |
| unsigned int free_swap = count_swap_pages(root_swap, 1); |
| unsigned int required; |
| |
| pr_debug("PM: Free swap pages: %u\n", free_swap); |
| |
| required = PAGES_FOR_IO + ((flags & SF_NOCOMPRESS_MODE) ? |
| nr_pages : (nr_pages * LZO_CMP_PAGES) / LZO_UNC_PAGES + 1); |
| return free_swap > required; |
| } |
| |
| /** |
| * swsusp_write - Write entire image and metadata. |
| * @flags: flags to pass to the "boot" kernel in the image header |
| * |
| * 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(unsigned int flags) |
| { |
| struct swap_map_handle handle; |
| struct snapshot_handle snapshot; |
| struct swsusp_info *header; |
| unsigned long pages; |
| int error; |
| |
| pages = snapshot_get_image_size(); |
| error = get_swap_writer(&handle); |
| if (error) { |
| printk(KERN_ERR "PM: Cannot get swap writer\n"); |
| return error; |
| } |
| if (!enough_swap(pages, flags)) { |
| printk(KERN_ERR "PM: Not enough free swap\n"); |
| error = -ENOSPC; |
| goto out_finish; |
| } |
| memset(&snapshot, 0, sizeof(struct snapshot_handle)); |
| error = snapshot_read_next(&snapshot); |
| if (error < PAGE_SIZE) { |
| if (error >= 0) |
| error = -EFAULT; |
| |
| goto out_finish; |
| } |
| header = (struct swsusp_info *)data_of(snapshot); |
| error = swap_write_page(&handle, header, NULL); |
| if (!error) { |
| error = (flags & SF_NOCOMPRESS_MODE) ? |
| save_image(&handle, &snapshot, pages - 1) : |
| save_image_lzo(&handle, &snapshot, pages - 1); |
| } |
| out_finish: |
| error = swap_writer_finish(&handle, flags, error); |
| return error; |
| } |
| |
| /** |
| * The following functions allow us to read data using a swap map |
| * in a file-alike way |
| */ |
| |
| static void release_swap_reader(struct swap_map_handle *handle) |
| { |
| struct swap_map_page_list *tmp; |
| |
| while (handle->maps) { |
| if (handle->maps->map) |
| free_page((unsigned long)handle->maps->map); |
| tmp = handle->maps; |
| handle->maps = handle->maps->next; |
| kfree(tmp); |
| } |
| handle->cur = NULL; |
| } |
| |
| static int get_swap_reader(struct swap_map_handle *handle, |
| unsigned int *flags_p) |
| { |
| int error; |
| struct swap_map_page_list *tmp, *last; |
| sector_t offset; |
| |
| *flags_p = swsusp_header->flags; |
| |
| if (!swsusp_header->image) /* how can this happen? */ |
| return -EINVAL; |
| |
| handle->cur = NULL; |
| last = handle->maps = NULL; |
| offset = swsusp_header->image; |
| while (offset) { |
| tmp = kmalloc(sizeof(*handle->maps), GFP_KERNEL); |
| if (!tmp) { |
| release_swap_reader(handle); |
| return -ENOMEM; |
| } |
| memset(tmp, 0, sizeof(*tmp)); |
| if (!handle->maps) |
| handle->maps = tmp; |
| if (last) |
| last->next = tmp; |
| last = tmp; |
| |
| tmp->map = (struct swap_map_page *) |
| __get_free_page(__GFP_WAIT | __GFP_HIGH); |
| if (!tmp->map) { |
| release_swap_reader(handle); |
| return -ENOMEM; |
| } |
| |
| error = hib_bio_read_page(offset, tmp->map, NULL); |
| if (error) { |
| release_swap_reader(handle); |
| return error; |
| } |
| offset = tmp->map->next_swap; |
| } |
| handle->k = 0; |
| handle->cur = handle->maps->map; |
| return 0; |
| } |
| |
| static int swap_read_page(struct swap_map_handle *handle, void *buf, |
| struct bio **bio_chain) |
| { |
| sector_t offset; |
| int error; |
| struct swap_map_page_list *tmp; |
| |
| if (!handle->cur) |
| return -EINVAL; |
| offset = handle->cur->entries[handle->k]; |
| if (!offset) |
| return -EFAULT; |
| error = hib_bio_read_page(offset, buf, bio_chain); |
| if (error) |
| return error; |
| if (++handle->k >= MAP_PAGE_ENTRIES) { |
| handle->k = 0; |
| free_page((unsigned long)handle->maps->map); |
| tmp = handle->maps; |
| handle->maps = handle->maps->next; |
| kfree(tmp); |
| if (!handle->maps) |
| release_swap_reader(handle); |
| else |
| handle->cur = handle->maps->map; |
| } |
| return error; |
| } |
| |
| static int swap_reader_finish(struct swap_map_handle *handle) |
| { |
| release_swap_reader(handle); |
| |
| return 0; |
| } |
| |
| /** |
| * 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(struct swap_map_handle *handle, |
| struct snapshot_handle *snapshot, |
| unsigned int nr_to_read) |
| { |
| unsigned int m; |
| int ret = 0; |
| struct timeval start; |
| struct timeval stop; |
| struct bio *bio; |
| int err2; |
| unsigned nr_pages; |
| |
| printk(KERN_INFO "PM: Loading image data pages (%u pages) ... ", |
| nr_to_read); |
| m = nr_to_read / 100; |
| if (!m) |
| m = 1; |
| nr_pages = 0; |
| bio = NULL; |
| do_gettimeofday(&start); |
| for ( ; ; ) { |
| ret = snapshot_write_next(snapshot); |
| if (ret <= 0) |
| break; |
| ret = swap_read_page(handle, data_of(*snapshot), &bio); |
| if (ret) |
| break; |
| if (snapshot->sync_read) |
| ret = hib_wait_on_bio_chain(&bio); |
| if (ret) |
| break; |
| if (!(nr_pages % m)) |
| printk("\b\b\b\b%3d%%", nr_pages / m); |
| nr_pages++; |
| } |
| err2 = hib_wait_on_bio_chain(&bio); |
| do_gettimeofday(&stop); |
| if (!ret) |
| ret = err2; |
| if (!ret) { |
| printk("\b\b\b\bdone\n"); |
| snapshot_write_finalize(snapshot); |
| if (!snapshot_image_loaded(snapshot)) |
| ret = -ENODATA; |
| } else |
| printk("\n"); |
| swsusp_show_speed(&start, &stop, nr_to_read, "Read"); |
| return ret; |
| } |
| |
| /** |
| * Structure used for LZO data decompression. |
| */ |
| struct dec_data { |
| struct task_struct *thr; /* thread */ |
| atomic_t ready; /* ready to start flag */ |
| atomic_t stop; /* ready to stop flag */ |
| int ret; /* return code */ |
| wait_queue_head_t go; /* start decompression */ |
| wait_queue_head_t done; /* decompression done */ |
| size_t unc_len; /* uncompressed length */ |
| size_t cmp_len; /* compressed length */ |
| unsigned char unc[LZO_UNC_SIZE]; /* uncompressed buffer */ |
| unsigned char cmp[LZO_CMP_SIZE]; /* compressed buffer */ |
| }; |
| |
| /** |
| * Deompression function that runs in its own thread. |
| */ |
| static int lzo_decompress_threadfn(void *data) |
| { |
| struct dec_data *d = data; |
| |
| while (1) { |
| wait_event(d->go, atomic_read(&d->ready) || |
| kthread_should_stop()); |
| if (kthread_should_stop()) { |
| d->thr = NULL; |
| d->ret = -1; |
| atomic_set(&d->stop, 1); |
| wake_up(&d->done); |
| break; |
| } |
| atomic_set(&d->ready, 0); |
| |
| d->unc_len = LZO_UNC_SIZE; |
| d->ret = lzo1x_decompress_safe(d->cmp + LZO_HEADER, d->cmp_len, |
| d->unc, &d->unc_len); |
| atomic_set(&d->stop, 1); |
| wake_up(&d->done); |
| } |
| return 0; |
| } |
| |
| /** |
| * load_image_lzo - Load compressed image data and decompress them with LZO. |
| * @handle: Swap map handle to use for loading data. |
| * @snapshot: Image to copy uncompressed data into. |
| * @nr_to_read: Number of pages to load. |
| */ |
| static int load_image_lzo(struct swap_map_handle *handle, |
| struct snapshot_handle *snapshot, |
| unsigned int nr_to_read) |
| { |
| unsigned int m; |
| int ret = 0; |
| int eof = 0; |
| struct bio *bio; |
| struct timeval start; |
| struct timeval stop; |
| unsigned nr_pages; |
| size_t off; |
| unsigned i, thr, run_threads, nr_threads; |
| unsigned ring = 0, pg = 0, ring_size = 0, |
| have = 0, want, need, asked = 0; |
| unsigned long read_pages = 0; |
| unsigned char **page = NULL; |
| struct dec_data *data = NULL; |
| struct crc_data *crc = NULL; |
| |
| /* |
| * We'll limit the number of threads for decompression to limit memory |
| * footprint. |
| */ |
| nr_threads = num_online_cpus() - 1; |
| nr_threads = clamp_val(nr_threads, 1, LZO_THREADS); |
| |
| page = vmalloc(sizeof(*page) * LZO_MAX_RD_PAGES); |
| if (!page) { |
| printk(KERN_ERR "PM: Failed to allocate LZO page\n"); |
| ret = -ENOMEM; |
| goto out_clean; |
| } |
| |
| data = vmalloc(sizeof(*data) * nr_threads); |
| if (!data) { |
| printk(KERN_ERR "PM: Failed to allocate LZO data\n"); |
| ret = -ENOMEM; |
| goto out_clean; |
| } |
| for (thr = 0; thr < nr_threads; thr++) |
| memset(&data[thr], 0, offsetof(struct dec_data, go)); |
| |
| crc = kmalloc(sizeof(*crc), GFP_KERNEL); |
| if (!crc) { |
| printk(KERN_ERR "PM: Failed to allocate crc\n"); |
| ret = -ENOMEM; |
| goto out_clean; |
| } |
| memset(crc, 0, offsetof(struct crc_data, go)); |
| |
| /* |
| * Start the decompression threads. |
| */ |
| for (thr = 0; thr < nr_threads; thr++) { |
| init_waitqueue_head(&data[thr].go); |
| init_waitqueue_head(&data[thr].done); |
| |
| data[thr].thr = kthread_run(lzo_decompress_threadfn, |
| &data[thr], |
| "image_decompress/%u", thr); |
| if (IS_ERR(data[thr].thr)) { |
| data[thr].thr = NULL; |
| printk(KERN_ERR |
| "PM: Cannot start decompression threads\n"); |
| ret = -ENOMEM; |
| goto out_clean; |
| } |
| } |
| |
| /* |
| * Start the CRC32 thread. |
| */ |
| init_waitqueue_head(&crc->go); |
| init_waitqueue_head(&crc->done); |
| |
| handle->crc32 = 0; |
| crc->crc32 = &handle->crc32; |
| for (thr = 0; thr < nr_threads; thr++) { |
| crc->unc[thr] = data[thr].unc; |
| crc->unc_len[thr] = &data[thr].unc_len; |
| } |
| |
| crc->thr = kthread_run(crc32_threadfn, crc, "image_crc32"); |
| if (IS_ERR(crc->thr)) { |
| crc->thr = NULL; |
| printk(KERN_ERR "PM: Cannot start CRC32 thread\n"); |
| ret = -ENOMEM; |
| goto out_clean; |
| } |
| |
| /* |
| * Set the number of pages for read buffering. |
| * This is complete guesswork, because we'll only know the real |
| * picture once prepare_image() is called, which is much later on |
| * during the image load phase. We'll assume the worst case and |
| * say that none of the image pages are from high memory. |
| */ |
| if (low_free_pages() > snapshot_get_image_size()) |
| read_pages = (low_free_pages() - snapshot_get_image_size()) / 2; |
| read_pages = clamp_val(read_pages, LZO_MIN_RD_PAGES, LZO_MAX_RD_PAGES); |
| |
| for (i = 0; i < read_pages; i++) { |
| page[i] = (void *)__get_free_page(i < LZO_CMP_PAGES ? |
| __GFP_WAIT | __GFP_HIGH : |
| __GFP_WAIT | __GFP_NOWARN | |
| __GFP_NORETRY); |
| |
| if (!page[i]) { |
| if (i < LZO_CMP_PAGES) { |
| ring_size = i; |
| printk(KERN_ERR |
| "PM: Failed to allocate LZO pages\n"); |
| ret = -ENOMEM; |
| goto out_clean; |
| } else { |
| break; |
| } |
| } |
| } |
| want = ring_size = i; |
| |
| printk(KERN_INFO |
| "PM: Using %u thread(s) for decompression.\n" |
| "PM: Loading and decompressing image data (%u pages) ... ", |
| nr_threads, nr_to_read); |
| m = nr_to_read / 100; |
| if (!m) |
| m = 1; |
| nr_pages = 0; |
| bio = NULL; |
| do_gettimeofday(&start); |
| |
| ret = snapshot_write_next(snapshot); |
| if (ret <= 0) |
| goto out_finish; |
| |
| for(;;) { |
| for (i = 0; !eof && i < want; i++) { |
| ret = swap_read_page(handle, page[ring], &bio); |
| if (ret) { |
| /* |
| * On real read error, finish. On end of data, |
| * set EOF flag and just exit the read loop. |
| */ |
| if (handle->cur && |
| handle->cur->entries[handle->k]) { |
| goto out_finish; |
| } else { |
| eof = 1; |
| break; |
| } |
| } |
| if (++ring >= ring_size) |
| ring = 0; |
| } |
| asked += i; |
| want -= i; |
| |
| /* |
| * We are out of data, wait for some more. |
| */ |
| if (!have) { |
| if (!asked) |
| break; |
| |
| ret = hib_wait_on_bio_chain(&bio); |
| if (ret) |
| goto out_finish; |
| have += asked; |
| asked = 0; |
| if (eof) |
| eof = 2; |
| } |
| |
| if (crc->run_threads) { |
| wait_event(crc->done, atomic_read(&crc->stop)); |
| atomic_set(&crc->stop, 0); |
| crc->run_threads = 0; |
| } |
| |
| for (thr = 0; have && thr < nr_threads; thr++) { |
| data[thr].cmp_len = *(size_t *)page[pg]; |
| if (unlikely(!data[thr].cmp_len || |
| data[thr].cmp_len > |
| lzo1x_worst_compress(LZO_UNC_SIZE))) { |
| printk(KERN_ERR |
| "PM: Invalid LZO compressed length\n"); |
| ret = -1; |
| goto out_finish; |
| } |
| |
| need = DIV_ROUND_UP(data[thr].cmp_len + LZO_HEADER, |
| PAGE_SIZE); |
| if (need > have) { |
| if (eof > 1) { |
| ret = -1; |
| goto out_finish; |
| } |
| break; |
| } |
| |
| for (off = 0; |
| off < LZO_HEADER + data[thr].cmp_len; |
| off += PAGE_SIZE) { |
| memcpy(data[thr].cmp + off, |
| page[pg], PAGE_SIZE); |
| have--; |
| want++; |
| if (++pg >= ring_size) |
| pg = 0; |
| } |
| |
| atomic_set(&data[thr].ready, 1); |
| wake_up(&data[thr].go); |
| } |
| |
| /* |
| * Wait for more data while we are decompressing. |
| */ |
| if (have < LZO_CMP_PAGES && asked) { |
| ret = hib_wait_on_bio_chain(&bio); |
| if (ret) |
| goto out_finish; |
| have += asked; |
| asked = 0; |
| if (eof) |
| eof = 2; |
| } |
| |
| for (run_threads = thr, thr = 0; thr < run_threads; thr++) { |
| wait_event(data[thr].done, |
| atomic_read(&data[thr].stop)); |
| atomic_set(&data[thr].stop, 0); |
| |
| ret = data[thr].ret; |
| |
| if (ret < 0) { |
| printk(KERN_ERR |
| "PM: LZO decompression failed\n"); |
| goto out_finish; |
| } |
| |
| if (unlikely(!data[thr].unc_len || |
| data[thr].unc_len > LZO_UNC_SIZE || |
| data[thr].unc_len & (PAGE_SIZE - 1))) { |
| printk(KERN_ERR |
| "PM: Invalid LZO uncompressed length\n"); |
| ret = -1; |
| goto out_finish; |
| } |
| |
| for (off = 0; |
| off < data[thr].unc_len; off += PAGE_SIZE) { |
| memcpy(data_of(*snapshot), |
| data[thr].unc + off, PAGE_SIZE); |
| |
| if (!(nr_pages % m)) |
| printk("\b\b\b\b%3d%%", nr_pages / m); |
| nr_pages++; |
| |
| ret = snapshot_write_next(snapshot); |
| if (ret <= 0) { |
| crc->run_threads = thr + 1; |
| atomic_set(&crc->ready, 1); |
| wake_up(&crc->go); |
| goto out_finish; |
| } |
| } |
| } |
| |
| crc->run_threads = thr; |
| atomic_set(&crc->ready, 1); |
| wake_up(&crc->go); |
| } |
| |
| out_finish: |
| if (crc->run_threads) { |
| wait_event(crc->done, atomic_read(&crc->stop)); |
| atomic_set(&crc->stop, 0); |
| } |
| do_gettimeofday(&stop); |
| if (!ret) { |
| printk("\b\b\b\bdone\n"); |
| snapshot_write_finalize(snapshot); |
| if (!snapshot_image_loaded(snapshot)) |
| ret = -ENODATA; |
| if (!ret) { |
| if (swsusp_header->flags & SF_CRC32_MODE) { |
| if(handle->crc32 != swsusp_header->crc32) { |
| printk(KERN_ERR |
| "PM: Invalid image CRC32!\n"); |
| ret = -ENODATA; |
| } |
| } |
| } |
| } else |
| printk("\n"); |
| swsusp_show_speed(&start, &stop, nr_to_read, "Read"); |
| out_clean: |
| for (i = 0; i < ring_size; i++) |
| free_page((unsigned long)page[i]); |
| if (crc) { |
| if (crc->thr) |
| kthread_stop(crc->thr); |
| kfree(crc); |
| } |
| if (data) { |
| for (thr = 0; thr < nr_threads; thr++) |
| if (data[thr].thr) |
| kthread_stop(data[thr].thr); |
| vfree(data); |
| } |
| if (page) vfree(page); |
| |
| return ret; |
| } |
| |
| /** |
| * swsusp_read - read the hibernation image. |
| * @flags_p: flags passed by the "frozen" kernel in the image header should |
| * be written into this memory location |
| */ |
| |
| int swsusp_read(unsigned int *flags_p) |
| { |
| int error; |
| struct swap_map_handle handle; |
| struct snapshot_handle snapshot; |
| struct swsusp_info *header; |
| |
| memset(&snapshot, 0, sizeof(struct snapshot_handle)); |
| error = snapshot_write_next(&snapshot); |
| if (error < PAGE_SIZE) |
| return error < 0 ? error : -EFAULT; |
| header = (struct swsusp_info *)data_of(snapshot); |
| error = get_swap_reader(&handle, flags_p); |
| if (error) |
| goto end; |
| if (!error) |
| error = swap_read_page(&handle, header, NULL); |
| if (!error) { |
| error = (*flags_p & SF_NOCOMPRESS_MODE) ? |
| load_image(&handle, &snapshot, header->pages - 1) : |
| load_image_lzo(&handle, &snapshot, header->pages - 1); |
| } |
| swap_reader_finish(&handle); |
| end: |
| if (!error) |
| pr_debug("PM: Image successfully loaded\n"); |
| else |
| pr_debug("PM: Error %d resuming\n", error); |
| return error; |
| } |
| |
| /** |
| * swsusp_check - Check for swsusp signature in the resume device |
| */ |
| |
| int swsusp_check(void) |
| { |
| int error; |
| |
| hib_resume_bdev = blkdev_get_by_dev(swsusp_resume_device, |
| FMODE_READ, NULL); |
| if (!IS_ERR(hib_resume_bdev)) { |
| set_blocksize(hib_resume_bdev, PAGE_SIZE); |
| clear_page(swsusp_header); |
| error = hib_bio_read_page(swsusp_resume_block, |
| swsusp_header, NULL); |
| if (error) |
| goto put; |
| |
| if (!memcmp(HIBERNATE_SIG, swsusp_header->sig, 10)) { |
| memcpy(swsusp_header->sig, swsusp_header->orig_sig, 10); |
| /* Reset swap signature now */ |
| error = hib_bio_write_page(swsusp_resume_block, |
| swsusp_header, NULL); |
| } else { |
| error = -EINVAL; |
| } |
| |
| put: |
| if (error) |
| blkdev_put(hib_resume_bdev, FMODE_READ); |
| else |
| pr_debug("PM: Image signature found, resuming\n"); |
| } else { |
| error = PTR_ERR(hib_resume_bdev); |
| } |
| |
| if (error) |
| pr_debug("PM: Image not found (code %d)\n", error); |
| |
| return error; |
| } |
| |
| /** |
| * swsusp_close - close swap device. |
| */ |
| |
| void swsusp_close(fmode_t mode) |
| { |
| if (IS_ERR(hib_resume_bdev)) { |
| pr_debug("PM: Image device not initialised\n"); |
| return; |
| } |
| |
| blkdev_put(hib_resume_bdev, mode); |
| } |
| |
| static int swsusp_header_init(void) |
| { |
| swsusp_header = (struct swsusp_header*) __get_free_page(GFP_KERNEL); |
| if (!swsusp_header) |
| panic("Could not allocate memory for swsusp_header\n"); |
| return 0; |
| } |
| |
| core_initcall(swsusp_header_init); |