@@ -1,1668 +1,1717 @@
-// SPDX-License-Identifier: GPL-2.0-only
-/*
- * 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>
- */
-
-#define pr_fmt(fmt) "PM: " fmt
-
-#include <linux/module.h>
-#include <linux/file.h>
-#include <linux/delay.h>
-#include <linux/bitops.h>
-#include <linux/device.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/vmalloc.h>
-#include <linux/cpumask.h>
-#include <linux/atomic.h>
-#include <linux/kthread.h>
-#include <linux/crc32.h>
-#include <linux/ktime.h>
-
-#include "power.h"
-
-#define HIBERNATE_SIG "S1SUSPEND"
-
-u32 swsusp_hardware_signature;
-
-/*
- * When reading an {un,}compressed image, we may restore pages in place,
- * in which case some architectures need these pages cleaning before they
- * can be executed. We don't know which pages these may be, so clean the lot.
- */
-static bool clean_pages_on_read;
-static bool clean_pages_on_decompress;
-
-/*
- * 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) - sizeof(u32)];
- u32 hw_sig;
- u32 crc32;
- sector_t image;
- unsigned int flags; /* Flags to pass to the "boot" kernel */
- char orig_sig[10];
- char sig[10];
-} __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 = rb_entry(*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 = rb_entry(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;
-static struct file *hib_resume_bdev_file;
-
-struct hib_bio_batch {
- atomic_t count;
- wait_queue_head_t wait;
- blk_status_t error;
- struct blk_plug plug;
-};
-
-static void hib_init_batch(struct hib_bio_batch *hb)
-{
- atomic_set(&hb->count, 0);
- init_waitqueue_head(&hb->wait);
- hb->error = BLK_STS_OK;
- blk_start_plug(&hb->plug);
-}
-
-static void hib_finish_batch(struct hib_bio_batch *hb)
-{
- blk_finish_plug(&hb->plug);
-}
-
-static void hib_end_io(struct bio *bio)
-{
- struct hib_bio_batch *hb = bio->bi_private;
- struct page *page = bio_first_page_all(bio);
-
- if (bio->bi_status) {
- pr_alert("Read-error on swap-device (%u:%u:%Lu)\n",
- MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)),
- (unsigned long long)bio->bi_iter.bi_sector);
- }
-
- if (bio_data_dir(bio) == WRITE)
- put_page(page);
- else if (clean_pages_on_read)
- flush_icache_range((unsigned long)page_address(page),
- (unsigned long)page_address(page) + PAGE_SIZE);
-
- if (bio->bi_status && !hb->error)
- hb->error = bio->bi_status;
- if (atomic_dec_and_test(&hb->count))
- wake_up(&hb->wait);
-
- bio_put(bio);
-}
-
-static int hib_submit_io(blk_opf_t opf, pgoff_t page_off, void *addr,
- struct hib_bio_batch *hb)
-{
- struct page *page = virt_to_page(addr);
- struct bio *bio;
- int error = 0;
-
- bio = bio_alloc(file_bdev(hib_resume_bdev_file), 1, opf,
- GFP_NOIO | __GFP_HIGH);
- bio->bi_iter.bi_sector = page_off * (PAGE_SIZE >> 9);
-
- if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
- pr_err("Adding page to bio failed at %llu\n",
- (unsigned long long)bio->bi_iter.bi_sector);
- bio_put(bio);
- return -EFAULT;
- }
-
- if (hb) {
- bio->bi_end_io = hib_end_io;
- bio->bi_private = hb;
- atomic_inc(&hb->count);
- submit_bio(bio);
- } else {
- error = submit_bio_wait(bio);
- bio_put(bio);
- }
-
- return error;
-}
-
-static int hib_wait_io(struct hib_bio_batch *hb)
-{
- /*
- * We are relying on the behavior of blk_plug that a thread with
- * a plug will flush the plug list before sleeping.
- */
- wait_event(hb->wait, atomic_read(&hb->count) == 0);
- return blk_status_to_errno(hb->error);
-}
-
-/*
- * Saving part
- */
-static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
-{
- int error;
-
- hib_submit_io(REQ_OP_READ, 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;
- if (swsusp_hardware_signature) {
- swsusp_header->hw_sig = swsusp_hardware_signature;
- flags |= SF_HW_SIG;
- }
- swsusp_header->flags = flags;
- if (flags & SF_CRC32_MODE)
- swsusp_header->crc32 = handle->crc32;
- error = hib_submit_io(REQ_OP_WRITE | REQ_SYNC,
- swsusp_resume_block, swsusp_header, NULL);
- } else {
- pr_err("Swap header not found!\n");
- error = -ENODEV;
- }
- return error;
-}
-
-/*
- * Hold the swsusp_header flag. This is used in software_resume() in
- * 'kernel/power/hibernate' to check if the image is compressed and query
- * for the compression algorithm support(if so).
- */
-unsigned int swsusp_header_flags;
-
-/**
- * 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;
-
- if (swsusp_resume_device)
- res = swap_type_of(swsusp_resume_device, swsusp_resume_block);
- else
- res = find_first_swap(&swsusp_resume_device);
- if (res < 0)
- return res;
- root_swap = res;
-
- hib_resume_bdev_file = bdev_file_open_by_dev(swsusp_resume_device,
- BLK_OPEN_WRITE, NULL, NULL);
- if (IS_ERR(hib_resume_bdev_file))
- return PTR_ERR(hib_resume_bdev_file);
-
- res = set_blocksize(file_bdev(hib_resume_bdev_file), PAGE_SIZE);
- if (res < 0)
- fput(hib_resume_bdev_file);
-
- 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.
- * @hb: bio completion batch
- */
-
-static int write_page(void *buf, sector_t offset, struct hib_bio_batch *hb)
-{
- void *src;
- int ret;
-
- if (!offset)
- return -ENOSPC;
-
- if (hb) {
- src = (void *)__get_free_page(GFP_NOIO | __GFP_NOWARN |
- __GFP_NORETRY);
- if (src) {
- copy_page(src, buf);
- } else {
- ret = hib_wait_io(hb); /* Free pages */
- if (ret)
- return ret;
- src = (void *)__get_free_page(GFP_NOIO |
- __GFP_NOWARN |
- __GFP_NORETRY);
- if (src) {
- copy_page(src, buf);
- } else {
- WARN_ON_ONCE(1);
- hb = NULL; /* Go synchronous */
- src = buf;
- }
- }
- } else {
- src = buf;
- }
- return hib_submit_io(REQ_OP_WRITE | REQ_SYNC, offset, src, hb);
-}
-
-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)
- pr_err("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();
- return ret;
-}
-
-static int swap_write_page(struct swap_map_handle *handle, void *buf,
- struct hib_bio_batch *hb)
-{
- int error;
- sector_t offset;
-
- if (!handle->cur)
- return -EINVAL;
- offset = alloc_swapdev_block(root_swap);
- error = write_page(buf, offset, hb);
- 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, hb);
- if (error)
- goto out;
- clear_page(handle->cur);
- handle->cur_swap = offset;
- handle->k = 0;
-
- if (hb && low_free_pages() <= handle->reqd_free_pages) {
- error = hib_wait_io(hb);
- 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) {
- pr_info("S");
- error = mark_swapfiles(handle, flags);
- pr_cont("|\n");
- flush_swap_writer(handle);
- }
-
- if (error)
- free_all_swap_pages(root_swap);
- release_swap_writer(handle);
- swsusp_close();
-
- return error;
-}
-
-/*
- * Bytes we need for compressed data in worst case. We assume(limitation)
- * this is the worst of all the compression algorithms.
- */
-#define bytes_worst_compress(x) ((x) + ((x) / 16) + 64 + 3 + 2)
-
-/* We need to remember how much compressed data we need to read. */
-#define CMP_HEADER sizeof(size_t)
-
-/* Number of pages/bytes we'll compress at one time. */
-#define UNC_PAGES 32
-#define UNC_SIZE (UNC_PAGES * PAGE_SIZE)
-
-/* Number of pages we need for compressed data (worst case). */
-#define CMP_PAGES DIV_ROUND_UP(bytes_worst_compress(UNC_SIZE) + \
- CMP_HEADER, PAGE_SIZE)
-#define CMP_SIZE (CMP_PAGES * PAGE_SIZE)
-
-/* Maximum number of threads for compression/decompression. */
-#define CMP_THREADS 3
-
-/* Minimum/maximum number of pages for read buffering. */
-#define CMP_MIN_RD_PAGES 1024
-#define CMP_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 hib_bio_batch hb;
- ktime_t start;
- ktime_t stop;
-
- hib_init_batch(&hb);
-
- pr_info("Saving image data pages (%u pages)...\n",
- nr_to_write);
- m = nr_to_write / 10;
- if (!m)
- m = 1;
- nr_pages = 0;
- start = ktime_get();
- while (1) {
- ret = snapshot_read_next(snapshot);
- if (ret <= 0)
- break;
- ret = swap_write_page(handle, data_of(*snapshot), &hb);
- if (ret)
- break;
- if (!(nr_pages % m))
- pr_info("Image saving progress: %3d%%\n",
- nr_pages / m * 10);
- nr_pages++;
- }
- err2 = hib_wait_io(&hb);
- hib_finish_batch(&hb);
- stop = ktime_get();
- if (!ret)
- ret = err2;
- if (!ret)
- pr_info("Image saving done\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[CMP_THREADS]; /* uncompressed lengths */
- unsigned char *unc[CMP_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_acquire(&d->ready) ||
- kthread_should_stop());
- if (kthread_should_stop()) {
- d->thr = NULL;
- atomic_set_release(&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_release(&d->stop, 1);
- wake_up(&d->done);
- }
- return 0;
-}
-/*
- * Structure used for data compression.
- */
-struct cmp_data {
- struct task_struct *thr; /* thread */
- struct crypto_comp *cc; /* crypto compressor stream */
- 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[UNC_SIZE]; /* uncompressed buffer */
- unsigned char cmp[CMP_SIZE]; /* compressed buffer */
-};
-
-/* Indicates the image size after compression */
-static atomic_t compressed_size = ATOMIC_INIT(0);
-
-/*
- * Compression function that runs in its own thread.
- */
-static int compress_threadfn(void *data)
-{
- struct cmp_data *d = data;
- unsigned int cmp_len = 0;
-
- while (1) {
- wait_event(d->go, atomic_read_acquire(&d->ready) ||
- kthread_should_stop());
- if (kthread_should_stop()) {
- d->thr = NULL;
- d->ret = -1;
- atomic_set_release(&d->stop, 1);
- wake_up(&d->done);
- break;
- }
- atomic_set(&d->ready, 0);
-
- cmp_len = CMP_SIZE - CMP_HEADER;
- d->ret = crypto_comp_compress(d->cc, d->unc, d->unc_len,
- d->cmp + CMP_HEADER,
- &cmp_len);
- d->cmp_len = cmp_len;
-
- atomic_set(&compressed_size, atomic_read(&compressed_size) + d->cmp_len);
- atomic_set_release(&d->stop, 1);
- wake_up(&d->done);
- }
- return 0;
-}
-
-/**
- * save_compressed_image - Save the suspend image data after compression.
- * @handle: Swap map handle to use for saving the image.
- * @snapshot: Image to read data from.
- * @nr_to_write: Number of pages to save.
- */
-static int save_compressed_image(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 hib_bio_batch hb;
- ktime_t start;
- ktime_t stop;
- size_t off;
- unsigned thr, run_threads, nr_threads;
- unsigned char *page = NULL;
- struct cmp_data *data = NULL;
- struct crc_data *crc = NULL;
-
- hib_init_batch(&hb);
-
- atomic_set(&compressed_size, 0);
-
- /*
- * 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, CMP_THREADS);
-
- page = (void *)__get_free_page(GFP_NOIO | __GFP_HIGH);
- if (!page) {
- pr_err("Failed to allocate %s page\n", hib_comp_algo);
- ret = -ENOMEM;
- goto out_clean;
- }
-
- data = vzalloc(array_size(nr_threads, sizeof(*data)));
- if (!data) {
- pr_err("Failed to allocate %s data\n", hib_comp_algo);
- ret = -ENOMEM;
- goto out_clean;
- }
-
- crc = kzalloc(sizeof(*crc), GFP_KERNEL);
- if (!crc) {
- pr_err("Failed to allocate crc\n");
- ret = -ENOMEM;
- goto out_clean;
- }
-
- /*
- * 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].cc = crypto_alloc_comp(hib_comp_algo, 0, 0);
- if (IS_ERR_OR_NULL(data[thr].cc)) {
- pr_err("Could not allocate comp stream %ld\n", PTR_ERR(data[thr].cc));
- ret = -EFAULT;
- goto out_clean;
- }
-
- data[thr].thr = kthread_run(compress_threadfn,
- &data[thr],
- "image_compress/%u", thr);
- if (IS_ERR(data[thr].thr)) {
- data[thr].thr = NULL;
- pr_err("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;
- pr_err("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();
-
- pr_info("Using %u thread(s) for %s compression\n", nr_threads, hib_comp_algo);
- pr_info("Compressing and saving image data (%u pages)...\n",
- nr_to_write);
- m = nr_to_write / 10;
- if (!m)
- m = 1;
- nr_pages = 0;
- start = ktime_get();
- for (;;) {
- for (thr = 0; thr < nr_threads; thr++) {
- for (off = 0; off < 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))
- pr_info("Image saving progress: %3d%%\n",
- nr_pages / m * 10);
- nr_pages++;
- }
- if (!off)
- break;
-
- data[thr].unc_len = off;
-
- atomic_set_release(&data[thr].ready, 1);
- wake_up(&data[thr].go);
- }
-
- if (!thr)
- break;
-
- crc->run_threads = thr;
- atomic_set_release(&crc->ready, 1);
- wake_up(&crc->go);
-
- for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
- wait_event(data[thr].done,
- atomic_read_acquire(&data[thr].stop));
- atomic_set(&data[thr].stop, 0);
-
- ret = data[thr].ret;
-
- if (ret < 0) {
- pr_err("%s compression failed\n", hib_comp_algo);
- goto out_finish;
- }
-
- if (unlikely(!data[thr].cmp_len ||
- data[thr].cmp_len >
- bytes_worst_compress(data[thr].unc_len))) {
- pr_err("Invalid %s compressed length\n", hib_comp_algo);
- 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 < CMP_HEADER + data[thr].cmp_len;
- off += PAGE_SIZE) {
- memcpy(page, data[thr].cmp + off, PAGE_SIZE);
-
- ret = swap_write_page(handle, page, &hb);
- if (ret)
- goto out_finish;
- }
- }
-
- wait_event(crc->done, atomic_read_acquire(&crc->stop));
- atomic_set(&crc->stop, 0);
- }
-
-out_finish:
- err2 = hib_wait_io(&hb);
- stop = ktime_get();
- if (!ret)
- ret = err2;
- if (!ret)
- pr_info("Image saving done\n");
- swsusp_show_speed(start, stop, nr_to_write, "Wrote");
- pr_info("Image size after compression: %d kbytes\n",
- (atomic_read(&compressed_size) / 1024));
-
-out_clean:
- hib_finish_batch(&hb);
- 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);
- if (data[thr].cc)
- crypto_free_comp(data[thr].cc);
- }
- 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 available from the resume partition.
- */
-
-static int enough_swap(unsigned int nr_pages)
-{
- unsigned int free_swap = count_swap_pages(root_swap, 1);
- unsigned int required;
-
- pr_debug("Free swap pages: %u\n", free_swap);
-
- required = PAGES_FOR_IO + nr_pages;
- 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) {
- pr_err("Cannot get swap writer\n");
- return error;
- }
- if (flags & SF_NOCOMPRESS_MODE) {
- if (!enough_swap(pages)) {
- pr_err("Not enough free swap\n");
- error = -ENOSPC;
- goto out_finish;
- }
- }
- memset(&snapshot, 0, sizeof(struct snapshot_handle));
- error = snapshot_read_next(&snapshot);
- if (error < (int)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_compressed_image(&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-like 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 = kzalloc(sizeof(*handle->maps), GFP_KERNEL);
- if (!tmp) {
- release_swap_reader(handle);
- return -ENOMEM;
- }
- if (!handle->maps)
- handle->maps = tmp;
- if (last)
- last->next = tmp;
- last = tmp;
-
- tmp->map = (struct swap_map_page *)
- __get_free_page(GFP_NOIO | __GFP_HIGH);
- if (!tmp->map) {
- release_swap_reader(handle);
- return -ENOMEM;
- }
-
- error = hib_submit_io(REQ_OP_READ, 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 hib_bio_batch *hb)
-{
- 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_submit_io(REQ_OP_READ, offset, buf, hb);
- 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;
- ktime_t start;
- ktime_t stop;
- struct hib_bio_batch hb;
- int err2;
- unsigned nr_pages;
-
- hib_init_batch(&hb);
-
- clean_pages_on_read = true;
- pr_info("Loading image data pages (%u pages)...\n", nr_to_read);
- m = nr_to_read / 10;
- if (!m)
- m = 1;
- nr_pages = 0;
- start = ktime_get();
- for ( ; ; ) {
- ret = snapshot_write_next(snapshot);
- if (ret <= 0)
- break;
- ret = swap_read_page(handle, data_of(*snapshot), &hb);
- if (ret)
- break;
- if (snapshot->sync_read)
- ret = hib_wait_io(&hb);
- if (ret)
- break;
- if (!(nr_pages % m))
- pr_info("Image loading progress: %3d%%\n",
- nr_pages / m * 10);
- nr_pages++;
- }
- err2 = hib_wait_io(&hb);
- hib_finish_batch(&hb);
- stop = ktime_get();
- if (!ret)
- ret = err2;
- if (!ret) {
- pr_info("Image loading done\n");
- ret = snapshot_write_finalize(snapshot);
- if (!ret && !snapshot_image_loaded(snapshot))
- ret = -ENODATA;
- }
- swsusp_show_speed(start, stop, nr_to_read, "Read");
- return ret;
-}
-
-/*
- * Structure used for data decompression.
- */
-struct dec_data {
- struct task_struct *thr; /* thread */
- struct crypto_comp *cc; /* crypto compressor stream */
- 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[UNC_SIZE]; /* uncompressed buffer */
- unsigned char cmp[CMP_SIZE]; /* compressed buffer */
-};
-
-/*
- * Decompression function that runs in its own thread.
- */
-static int decompress_threadfn(void *data)
-{
- struct dec_data *d = data;
- unsigned int unc_len = 0;
-
- while (1) {
- wait_event(d->go, atomic_read_acquire(&d->ready) ||
- kthread_should_stop());
- if (kthread_should_stop()) {
- d->thr = NULL;
- d->ret = -1;
- atomic_set_release(&d->stop, 1);
- wake_up(&d->done);
- break;
- }
- atomic_set(&d->ready, 0);
-
- unc_len = UNC_SIZE;
- d->ret = crypto_comp_decompress(d->cc, d->cmp + CMP_HEADER, d->cmp_len,
- d->unc, &unc_len);
- d->unc_len = unc_len;
-
- if (clean_pages_on_decompress)
- flush_icache_range((unsigned long)d->unc,
- (unsigned long)d->unc + d->unc_len);
-
- atomic_set_release(&d->stop, 1);
- wake_up(&d->done);
- }
- return 0;
-}
-
-/**
- * load_compressed_image - Load compressed image data and decompress it.
- * @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_compressed_image(struct swap_map_handle *handle,
- struct snapshot_handle *snapshot,
- unsigned int nr_to_read)
-{
- unsigned int m;
- int ret = 0;
- int eof = 0;
- struct hib_bio_batch hb;
- ktime_t start;
- ktime_t 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;
-
- hib_init_batch(&hb);
-
- /*
- * 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, CMP_THREADS);
-
- page = vmalloc(array_size(CMP_MAX_RD_PAGES, sizeof(*page)));
- if (!page) {
- pr_err("Failed to allocate %s page\n", hib_comp_algo);
- ret = -ENOMEM;
- goto out_clean;
- }
-
- data = vzalloc(array_size(nr_threads, sizeof(*data)));
- if (!data) {
- pr_err("Failed to allocate %s data\n", hib_comp_algo);
- ret = -ENOMEM;
- goto out_clean;
- }
-
- crc = kzalloc(sizeof(*crc), GFP_KERNEL);
- if (!crc) {
- pr_err("Failed to allocate crc\n");
- ret = -ENOMEM;
- goto out_clean;
- }
-
- clean_pages_on_decompress = true;
-
- /*
- * 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].cc = crypto_alloc_comp(hib_comp_algo, 0, 0);
- if (IS_ERR_OR_NULL(data[thr].cc)) {
- pr_err("Could not allocate comp stream %ld\n", PTR_ERR(data[thr].cc));
- ret = -EFAULT;
- goto out_clean;
- }
-
- data[thr].thr = kthread_run(decompress_threadfn,
- &data[thr],
- "image_decompress/%u", thr);
- if (IS_ERR(data[thr].thr)) {
- data[thr].thr = NULL;
- pr_err("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;
- pr_err("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, CMP_MIN_RD_PAGES, CMP_MAX_RD_PAGES);
-
- for (i = 0; i < read_pages; i++) {
- page[i] = (void *)__get_free_page(i < CMP_PAGES ?
- GFP_NOIO | __GFP_HIGH :
- GFP_NOIO | __GFP_NOWARN |
- __GFP_NORETRY);
-
- if (!page[i]) {
- if (i < CMP_PAGES) {
- ring_size = i;
- pr_err("Failed to allocate %s pages\n", hib_comp_algo);
- ret = -ENOMEM;
- goto out_clean;
- } else {
- break;
- }
- }
- }
- want = ring_size = i;
-
- pr_info("Using %u thread(s) for %s decompression\n", nr_threads, hib_comp_algo);
- pr_info("Loading and decompressing image data (%u pages)...\n",
- nr_to_read);
- m = nr_to_read / 10;
- if (!m)
- m = 1;
- nr_pages = 0;
- start = ktime_get();
-
- 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], &hb);
- 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_io(&hb);
- if (ret)
- goto out_finish;
- have += asked;
- asked = 0;
- if (eof)
- eof = 2;
- }
-
- if (crc->run_threads) {
- wait_event(crc->done, atomic_read_acquire(&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 >
- bytes_worst_compress(UNC_SIZE))) {
- pr_err("Invalid %s compressed length\n", hib_comp_algo);
- ret = -1;
- goto out_finish;
- }
-
- need = DIV_ROUND_UP(data[thr].cmp_len + CMP_HEADER,
- PAGE_SIZE);
- if (need > have) {
- if (eof > 1) {
- ret = -1;
- goto out_finish;
- }
- break;
- }
-
- for (off = 0;
- off < CMP_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_release(&data[thr].ready, 1);
- wake_up(&data[thr].go);
- }
-
- /*
- * Wait for more data while we are decompressing.
- */
- if (have < CMP_PAGES && asked) {
- ret = hib_wait_io(&hb);
- 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_acquire(&data[thr].stop));
- atomic_set(&data[thr].stop, 0);
-
- ret = data[thr].ret;
-
- if (ret < 0) {
- pr_err("%s decompression failed\n", hib_comp_algo);
- goto out_finish;
- }
-
- if (unlikely(!data[thr].unc_len ||
- data[thr].unc_len > UNC_SIZE ||
- data[thr].unc_len & (PAGE_SIZE - 1))) {
- pr_err("Invalid %s uncompressed length\n", hib_comp_algo);
- 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))
- pr_info("Image loading progress: %3d%%\n",
- nr_pages / m * 10);
- nr_pages++;
-
- ret = snapshot_write_next(snapshot);
- if (ret <= 0) {
- crc->run_threads = thr + 1;
- atomic_set_release(&crc->ready, 1);
- wake_up(&crc->go);
- goto out_finish;
- }
- }
- }
-
- crc->run_threads = thr;
- atomic_set_release(&crc->ready, 1);
- wake_up(&crc->go);
- }
-
-out_finish:
- if (crc->run_threads) {
- wait_event(crc->done, atomic_read_acquire(&crc->stop));
- atomic_set(&crc->stop, 0);
- }
- stop = ktime_get();
- if (!ret) {
- pr_info("Image loading done\n");
- ret = snapshot_write_finalize(snapshot);
- if (!ret && !snapshot_image_loaded(snapshot))
- ret = -ENODATA;
- if (!ret) {
- if (swsusp_header->flags & SF_CRC32_MODE) {
- if(handle->crc32 != swsusp_header->crc32) {
- pr_err("Invalid image CRC32!\n");
- ret = -ENODATA;
- }
- }
- }
- }
- swsusp_show_speed(start, stop, nr_to_read, "Read");
-out_clean:
- hib_finish_batch(&hb);
- 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);
- if (data[thr].cc)
- crypto_free_comp(data[thr].cc);
- }
- vfree(data);
- }
- 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 < (int)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_compressed_image(&handle, &snapshot, header->pages - 1);
- }
- swap_reader_finish(&handle);
-end:
- if (!error)
- pr_debug("Image successfully loaded\n");
- else
- pr_debug("Error %d resuming\n", error);
- return error;
-}
-
-static void *swsusp_holder;
-
-/**
- * swsusp_check - Open the resume device and check for the swsusp signature.
- * @exclusive: Open the resume device exclusively.
- */
-
-int swsusp_check(bool exclusive)
-{
- void *holder = exclusive ? &swsusp_holder : NULL;
- int error;
-
- hib_resume_bdev_file = bdev_file_open_by_dev(swsusp_resume_device,
- BLK_OPEN_READ, holder, NULL);
- if (!IS_ERR(hib_resume_bdev_file)) {
- set_blocksize(file_bdev(hib_resume_bdev_file), PAGE_SIZE);
- clear_page(swsusp_header);
- error = hib_submit_io(REQ_OP_READ, 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);
- swsusp_header_flags = swsusp_header->flags;
- /* Reset swap signature now */
- error = hib_submit_io(REQ_OP_WRITE | REQ_SYNC,
- swsusp_resume_block,
- swsusp_header, NULL);
- } else {
- error = -EINVAL;
- }
- if (!error && swsusp_header->flags & SF_HW_SIG &&
- swsusp_header->hw_sig != swsusp_hardware_signature) {
- pr_info("Suspend image hardware signature mismatch (%08x now %08x); aborting resume.\n",
- swsusp_header->hw_sig, swsusp_hardware_signature);
- error = -EINVAL;
- }
-
-put:
- if (error)
- fput(hib_resume_bdev_file);
- else
- pr_debug("Image signature found, resuming\n");
- } else {
- error = PTR_ERR(hib_resume_bdev_file);
- }
-
- if (error)
- pr_debug("Image not found (code %d)\n", error);
-
- return error;
-}
-
-/**
- * swsusp_close - close resume device.
- */
-
-void swsusp_close(void)
-{
- if (IS_ERR(hib_resume_bdev_file)) {
- pr_debug("Image device not initialised\n");
- return;
- }
-
- fput(hib_resume_bdev_file);
-}
-
-/**
- * swsusp_unmark - Unmark swsusp signature in the resume device
- */
-
-#ifdef CONFIG_SUSPEND
-int swsusp_unmark(void)
-{
- int error;
-
- hib_submit_io(REQ_OP_READ, swsusp_resume_block,
- swsusp_header, NULL);
- if (!memcmp(HIBERNATE_SIG,swsusp_header->sig, 10)) {
- memcpy(swsusp_header->sig,swsusp_header->orig_sig, 10);
- error = hib_submit_io(REQ_OP_WRITE | REQ_SYNC,
- swsusp_resume_block,
- swsusp_header, NULL);
- } else {
- pr_err("Cannot find swsusp signature!\n");
- error = -ENODEV;
- }
-
- /*
- * We just returned from suspend, we don't need the image any more.
- */
- free_all_swap_pages(root_swap);
-
- return error;
-}
-#endif
-
-static int __init 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);
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * 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>
+ */
+
+#define pr_fmt(fmt) "PM: " fmt
+
+#include <linux/module.h>
+#include <linux/file.h>
+#include <linux/delay.h>
+#include <linux/bitops.h>
+#include <linux/device.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/vmalloc.h>
+#include <linux/cpumask.h>
+#include <linux/atomic.h>
+#include <linux/kthread.h>
+#include <linux/crc32.h>
+#include <linux/ktime.h>
+
+#include "power.h"
+
+#define HIBERNATE_SIG "S1SUSPEND"
+
+u32 swsusp_hardware_signature;
+
+/*
+ * When reading an {un,}compressed image, we may restore pages in place,
+ * in which case some architectures need these pages cleaning before they
+ * can be executed. We don't know which pages these may be, so clean the lot.
+ */
+static bool clean_pages_on_decompress;
+
+/*
+ * 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) - sizeof(u32)];
+ u32 hw_sig;
+ u32 crc32;
+ sector_t image;
+ unsigned int flags; /* Flags to pass to the "boot" kernel */
+ char orig_sig[10];
+ char sig[10];
+} __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 = rb_entry(*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 = rb_entry(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;
+static struct file *hib_resume_bdev_file;
+
+struct hib_bio_batch {
+ atomic_t count;
+ wait_queue_head_t wait;
+ blk_status_t error;
+ struct blk_plug plug;
+};
+
+static void hib_init_batch(struct hib_bio_batch *hb)
+{
+ atomic_set(&hb->count, 0);
+ init_waitqueue_head(&hb->wait);
+ hb->error = BLK_STS_OK;
+ blk_start_plug(&hb->plug);
+}
+
+static void hib_finish_batch(struct hib_bio_batch *hb)
+{
+ blk_finish_plug(&hb->plug);
+}
+
+static void hib_end_io(struct bio *bio)
+{
+ struct hib_bio_batch *hb = bio->bi_private;
+ struct page *page = bio_first_page_all(bio);
+
+ if (bio->bi_status) {
+ pr_alert("Read-error on swap-device (%u:%u:%Lu)\n",
+ MAJOR(bio_dev(bio)), MINOR(bio_dev(bio)),
+ (unsigned long long)bio->bi_iter.bi_sector);
+ }
+
+ if (bio_data_dir(bio) == WRITE)
+ put_page(page);
+
+ if (bio->bi_status && !hb->error)
+ hb->error = bio->bi_status;
+ if (atomic_dec_and_test(&hb->count))
+ wake_up(&hb->wait);
+
+ bio_put(bio);
+}
+
+static int hib_submit_io(blk_opf_t opf, pgoff_t page_off, void *addr,
+ struct hib_bio_batch *hb)
+{
+ struct page *page = virt_to_page(addr);
+ struct bio *bio;
+ int error = 0;
+
+ bio = bio_alloc(file_bdev(hib_resume_bdev_file), 1, opf,
+ GFP_NOIO | __GFP_HIGH);
+ bio->bi_iter.bi_sector = page_off * (PAGE_SIZE >> 9);
+
+ if (bio_add_page(bio, page, PAGE_SIZE, 0) < PAGE_SIZE) {
+ pr_err("Adding page to bio failed at %llu\n",
+ (unsigned long long)bio->bi_iter.bi_sector);
+ bio_put(bio);
+ return -EFAULT;
+ }
+
+ if (hb) {
+ bio->bi_end_io = hib_end_io;
+ bio->bi_private = hb;
+ atomic_inc(&hb->count);
+ submit_bio(bio);
+ } else {
+ error = submit_bio_wait(bio);
+ bio_put(bio);
+ }
+
+ return error;
+}
+
+static int hib_wait_io(struct hib_bio_batch *hb)
+{
+ /*
+ * We are relying on the behavior of blk_plug that a thread with
+ * a plug will flush the plug list before sleeping.
+ */
+ wait_event(hb->wait, atomic_read(&hb->count) == 0);
+ return blk_status_to_errno(hb->error);
+}
+
+/*
+ * Saving part
+ */
+static int mark_swapfiles(struct swap_map_handle *handle, unsigned int flags)
+{
+ int error;
+
+ hib_submit_io(REQ_OP_READ, 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;
+ if (swsusp_hardware_signature) {
+ swsusp_header->hw_sig = swsusp_hardware_signature;
+ flags |= SF_HW_SIG;
+ }
+ swsusp_header->flags = flags;
+ if (flags & SF_CRC32_MODE)
+ swsusp_header->crc32 = handle->crc32;
+ error = hib_submit_io(REQ_OP_WRITE | REQ_SYNC,
+ swsusp_resume_block, swsusp_header, NULL);
+ } else {
+ pr_err("Swap header not found!\n");
+ error = -ENODEV;
+ }
+ return error;
+}
+
+/*
+ * Hold the swsusp_header flag. This is used in software_resume() in
+ * 'kernel/power/hibernate' to check if the image is compressed and query
+ * for the compression algorithm support(if so).
+ */
+unsigned int swsusp_header_flags;
+
+/**
+ * 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;
+
+ if (swsusp_resume_device)
+ res = swap_type_of(swsusp_resume_device, swsusp_resume_block);
+ else
+ res = find_first_swap(&swsusp_resume_device);
+ if (res < 0)
+ return res;
+ root_swap = res;
+
+ hib_resume_bdev_file = bdev_file_open_by_dev(swsusp_resume_device,
+ BLK_OPEN_WRITE, NULL, NULL);
+ if (IS_ERR(hib_resume_bdev_file))
+ return PTR_ERR(hib_resume_bdev_file);
+
+ res = set_blocksize(file_bdev(hib_resume_bdev_file), PAGE_SIZE);
+ if (res < 0)
+ fput(hib_resume_bdev_file);
+
+ 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.
+ * @hb: bio completion batch
+ */
+
+static int write_page(void *buf, sector_t offset, struct hib_bio_batch *hb)
+{
+ void *src;
+ int ret;
+
+ if (!offset)
+ return -ENOSPC;
+
+ if (hb) {
+ src = (void *)__get_free_page(GFP_NOIO | __GFP_NOWARN |
+ __GFP_NORETRY);
+ if (src) {
+ copy_page(src, buf);
+ } else {
+ ret = hib_wait_io(hb); /* Free pages */
+ if (ret)
+ return ret;
+ src = (void *)__get_free_page(GFP_NOIO |
+ __GFP_NOWARN |
+ __GFP_NORETRY);
+ if (src) {
+ copy_page(src, buf);
+ } else {
+ WARN_ON_ONCE(1);
+ hb = NULL; /* Go synchronous */
+ src = buf;
+ }
+ }
+ } else {
+ src = buf;
+ }
+ return hib_submit_io(REQ_OP_WRITE | REQ_SYNC, offset, src, hb);
+}
+
+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)
+ pr_err("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();
+ return ret;
+}
+
+static int swap_write_page(struct swap_map_handle *handle, void *buf,
+ struct hib_bio_batch *hb)
+{
+ int error;
+ sector_t offset;
+
+ if (!handle->cur)
+ return -EINVAL;
+ offset = alloc_swapdev_block(root_swap);
+ error = write_page(buf, offset, hb);
+ 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, hb);
+ if (error)
+ goto out;
+ clear_page(handle->cur);
+ handle->cur_swap = offset;
+ handle->k = 0;
+
+ if (hb && low_free_pages() <= handle->reqd_free_pages) {
+ error = hib_wait_io(hb);
+ 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) {
+ pr_info("S");
+ error = mark_swapfiles(handle, flags);
+ pr_cont("|\n");
+ flush_swap_writer(handle);
+ }
+
+ if (error)
+ free_all_swap_pages(root_swap);
+ release_swap_writer(handle);
+ swsusp_close();
+
+ return error;
+}
+
+/*
+ * Bytes we need for compressed data in worst case. We assume(limitation)
+ * this is the worst of all the compression algorithms.
+ */
+#define bytes_worst_compress(x) ((x) + ((x) / 16) + 64 + 3 + 2)
+
+/* We need to remember how much compressed data we need to read. */
+#define CMP_HEADER sizeof(size_t)
+
+/* Number of pages/bytes we'll compress at one time. */
+#define UNC_PAGES 32
+#define UNC_SIZE (UNC_PAGES * PAGE_SIZE)
+
+/* Number of pages we need for compressed data (worst case). */
+#define CMP_PAGES DIV_ROUND_UP(bytes_worst_compress(UNC_SIZE) + \
+ CMP_HEADER, PAGE_SIZE)
+#define CMP_SIZE (CMP_PAGES * PAGE_SIZE)
+
+/* Maximum number of threads for compression/decompression. */
+#define CMP_THREADS 3
+
+/* Minimum/maximum number of pages for read buffering. */
+#define CMP_MIN_RD_PAGES 1024
+#define CMP_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 hib_bio_batch hb;
+ ktime_t start;
+ ktime_t stop;
+
+ hib_init_batch(&hb);
+
+ pr_info("Saving image data pages (%u pages)...\n",
+ nr_to_write);
+ m = nr_to_write / 10;
+ if (!m)
+ m = 1;
+ nr_pages = 0;
+ start = ktime_get();
+ while (1) {
+ ret = snapshot_read_next(snapshot);
+ if (ret <= 0)
+ break;
+ ret = swap_write_page(handle, data_of(*snapshot), &hb);
+ if (ret)
+ break;
+ if (!(nr_pages % m))
+ pr_info("Image saving progress: %3d%%\n",
+ nr_pages / m * 10);
+ nr_pages++;
+ }
+ err2 = hib_wait_io(&hb);
+ hib_finish_batch(&hb);
+ stop = ktime_get();
+ if (!ret)
+ ret = err2;
+ if (!ret)
+ pr_info("Image saving done\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[CMP_THREADS]; /* uncompressed lengths */
+ unsigned char *unc[CMP_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_acquire(&d->ready) ||
+ kthread_should_stop());
+ if (kthread_should_stop()) {
+ d->thr = NULL;
+ atomic_set_release(&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_release(&d->stop, 1);
+ wake_up(&d->done);
+ }
+ return 0;
+}
+/*
+ * Structure used for data compression.
+ */
+struct cmp_data {
+ struct task_struct *thr; /* thread */
+ struct crypto_comp *cc; /* crypto compressor stream */
+ 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[UNC_SIZE]; /* uncompressed buffer */
+ unsigned char cmp[CMP_SIZE]; /* compressed buffer */
+};
+
+/* Indicates the image size after compression */
+static atomic_t compressed_size = ATOMIC_INIT(0);
+
+/*
+ * Compression function that runs in its own thread.
+ */
+static int compress_threadfn(void *data)
+{
+ struct cmp_data *d = data;
+ unsigned int cmp_len = 0;
+
+ while (1) {
+ wait_event(d->go, atomic_read_acquire(&d->ready) ||
+ kthread_should_stop());
+ if (kthread_should_stop()) {
+ d->thr = NULL;
+ d->ret = -1;
+ atomic_set_release(&d->stop, 1);
+ wake_up(&d->done);
+ break;
+ }
+ atomic_set(&d->ready, 0);
+
+ cmp_len = CMP_SIZE - CMP_HEADER;
+ d->ret = crypto_comp_compress(d->cc, d->unc, d->unc_len,
+ d->cmp + CMP_HEADER,
+ &cmp_len);
+ d->cmp_len = cmp_len;
+
+ atomic_set(&compressed_size, atomic_read(&compressed_size) + d->cmp_len);
+ atomic_set_release(&d->stop, 1);
+ wake_up(&d->done);
+ }
+ return 0;
+}
+
+/**
+ * save_compressed_image - Save the suspend image data after compression.
+ * @handle: Swap map handle to use for saving the image.
+ * @snapshot: Image to read data from.
+ * @nr_to_write: Number of pages to save.
+ */
+static int save_compressed_image(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 hib_bio_batch hb;
+ ktime_t start;
+ ktime_t stop;
+ size_t off;
+ unsigned thr, run_threads, nr_threads;
+ unsigned char *page = NULL;
+ struct cmp_data *data = NULL;
+ struct crc_data *crc = NULL;
+
+ hib_init_batch(&hb);
+
+ atomic_set(&compressed_size, 0);
+
+ /*
+ * 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, CMP_THREADS);
+
+ page = (void *)__get_free_page(GFP_NOIO | __GFP_HIGH);
+ if (!page) {
+ pr_err("Failed to allocate %s page\n", hib_comp_algo);
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+
+ data = vzalloc(array_size(nr_threads, sizeof(*data)));
+ if (!data) {
+ pr_err("Failed to allocate %s data\n", hib_comp_algo);
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+
+ crc = kzalloc(sizeof(*crc), GFP_KERNEL);
+ if (!crc) {
+ pr_err("Failed to allocate crc\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+
+ /*
+ * 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].cc = crypto_alloc_comp(hib_comp_algo, 0, 0);
+ if (IS_ERR_OR_NULL(data[thr].cc)) {
+ pr_err("Could not allocate comp stream %ld\n", PTR_ERR(data[thr].cc));
+ ret = -EFAULT;
+ goto out_clean;
+ }
+
+ data[thr].thr = kthread_run(compress_threadfn,
+ &data[thr],
+ "image_compress/%u", thr);
+ if (IS_ERR(data[thr].thr)) {
+ data[thr].thr = NULL;
+ pr_err("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;
+ pr_err("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();
+
+ pr_info("Using %u thread(s) for %s compression\n", nr_threads, hib_comp_algo);
+ pr_info("Compressing and saving image data (%u pages)...\n",
+ nr_to_write);
+ m = nr_to_write / 10;
+ if (!m)
+ m = 1;
+ nr_pages = 0;
+ start = ktime_get();
+ for (;;) {
+ for (thr = 0; thr < nr_threads; thr++) {
+ for (off = 0; off < 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))
+ pr_info("Image saving progress: %3d%%\n",
+ nr_pages / m * 10);
+ nr_pages++;
+ }
+ if (!off)
+ break;
+
+ data[thr].unc_len = off;
+
+ atomic_set_release(&data[thr].ready, 1);
+ wake_up(&data[thr].go);
+ }
+
+ if (!thr)
+ break;
+
+ crc->run_threads = thr;
+ atomic_set_release(&crc->ready, 1);
+ wake_up(&crc->go);
+
+ for (run_threads = thr, thr = 0; thr < run_threads; thr++) {
+ wait_event(data[thr].done,
+ atomic_read_acquire(&data[thr].stop));
+ atomic_set(&data[thr].stop, 0);
+
+ ret = data[thr].ret;
+
+ if (ret < 0) {
+ pr_err("%s compression failed\n", hib_comp_algo);
+ goto out_finish;
+ }
+
+ if (unlikely(!data[thr].cmp_len ||
+ data[thr].cmp_len >
+ bytes_worst_compress(data[thr].unc_len))) {
+ pr_err("Invalid %s compressed length\n", hib_comp_algo);
+ 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 < CMP_HEADER + data[thr].cmp_len;
+ off += PAGE_SIZE) {
+ memcpy(page, data[thr].cmp + off, PAGE_SIZE);
+
+ ret = swap_write_page(handle, page, &hb);
+ if (ret)
+ goto out_finish;
+ }
+ }
+
+ wait_event(crc->done, atomic_read_acquire(&crc->stop));
+ atomic_set(&crc->stop, 0);
+ }
+
+out_finish:
+ err2 = hib_wait_io(&hb);
+ stop = ktime_get();
+ if (!ret)
+ ret = err2;
+ if (!ret)
+ pr_info("Image saving done\n");
+ swsusp_show_speed(start, stop, nr_to_write, "Wrote");
+ pr_info("Image size after compression: %d kbytes\n",
+ (atomic_read(&compressed_size) / 1024));
+
+out_clean:
+ hib_finish_batch(&hb);
+ 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);
+ if (data[thr].cc)
+ crypto_free_comp(data[thr].cc);
+ }
+ 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 available from the resume partition.
+ */
+
+static int enough_swap(unsigned int nr_pages)
+{
+ unsigned int free_swap = count_swap_pages(root_swap, 1);
+ unsigned int required;
+
+ pr_debug("Free swap pages: %u\n", free_swap);
+
+ required = PAGES_FOR_IO + nr_pages;
+ 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) {
+ pr_err("Cannot get swap writer\n");
+ return error;
+ }
+ if (flags & SF_NOCOMPRESS_MODE) {
+ if (!enough_swap(pages)) {
+ pr_err("Not enough free swap\n");
+ error = -ENOSPC;
+ goto out_finish;
+ }
+ }
+ memset(&snapshot, 0, sizeof(struct snapshot_handle));
+ error = snapshot_read_next(&snapshot);
+ if (error < (int)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_compressed_image(&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-like 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 = kzalloc(sizeof(*handle->maps), GFP_KERNEL);
+ if (!tmp) {
+ release_swap_reader(handle);
+ return -ENOMEM;
+ }
+ if (!handle->maps)
+ handle->maps = tmp;
+ if (last)
+ last->next = tmp;
+ last = tmp;
+
+ tmp->map = (struct swap_map_page *)
+ __get_free_page(GFP_NOIO | __GFP_HIGH);
+ if (!tmp->map) {
+ release_swap_reader(handle);
+ return -ENOMEM;
+ }
+
+ error = hib_submit_io(REQ_OP_READ, 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 hib_bio_batch *hb)
+{
+ 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_submit_io(REQ_OP_READ, offset, buf, hb);
+ 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;
+}
+
+struct swsusp_readpages {
+ unsigned long size;
+ unsigned long cursor;
+ struct page **pages;
+};
+
+static int swsusp_init_readpages(struct swsusp_readpages *read_pages, unsigned int nr_to_read)
+{
+ read_pages->pages = (struct page **)vzalloc(sizeof(struct page *) * nr_to_read);
+ if (!read_pages->pages) {
+ return -ENOMEM;
+ }
+
+ read_pages->size = nr_to_read;
+ read_pages->cursor = 0;
+
+ return 0;
+}
+
+
+static int swsusp_add_readpage(struct swsusp_readpages *read_pages, void *page_addr)
+{
+ if (read_pages->cursor >= read_pages->size) {
+ return -ENOMEM;
+ }
+
+ read_pages->pages[read_pages->cursor++] = virt_to_page(page_addr);
+ return 0;
+}
+
+static void swsusp_clean_readedpages(struct swsusp_readpages *read_pages, bool flush)
+{
+ unsigned long idx;
+
+ for (idx = 0; idx < read_pages->cursor; idx++) {
+ if (flush && read_pages->pages[idx])
+ flush_icache_range((unsigned long)page_address(read_pages->pages[idx]),
+ (unsigned long)page_address(read_pages->pages[idx] + PAGE_SIZE));
+ }
+
+ vfree(read_pages->pages);
+ return;
+}
+
+/**
+ * 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;
+ ktime_t start;
+ ktime_t stop;
+ struct hib_bio_batch hb;
+ int err2;
+ unsigned nr_pages;
+ struct swsusp_readpages pages_to_clean;
+
+ hib_init_batch(&hb);
+ ret = swsusp_init_readpages(&pages_to_clean, nr_to_read);
+ if (!ret) {
+ return ret;
+ }
+
+ pr_info("Loading image data pages (%u pages)...\n", nr_to_read);
+ m = nr_to_read / 10;
+ if (!m)
+ m = 1;
+ nr_pages = 0;
+ start = ktime_get();
+ for ( ; ; ) {
+ ret = snapshot_write_next(snapshot);
+ if (ret <= 0)
+ break;
+ ret = swap_read_page(handle, data_of(*snapshot), &hb);
+ if (ret)
+ break;
+ if (snapshot->sync_read)
+ ret = hib_wait_io(&hb);
+ if (ret)
+ break;
+ ret = swsusp_add_readpage(&pages_to_clean, data_of(*snapshot));
+ if (ret)
+ break;
+
+ if (!(nr_pages % m))
+ pr_info("Image loading progress: %3d%%\n",
+ nr_pages / m * 10);
+ nr_pages++;
+ }
+ err2 = hib_wait_io(&hb);
+ hib_finish_batch(&hb);
+ stop = ktime_get();
+ if (!ret)
+ ret = err2;
+ swsusp_clean_readedpages(&pages_to_clean, !ret);
+ if (!ret) {
+ pr_info("Image loading done\n");
+ ret = snapshot_write_finalize(snapshot);
+ if (!ret && !snapshot_image_loaded(snapshot))
+ ret = -ENODATA;
+ }
+ swsusp_show_speed(start, stop, nr_to_read, "Read");
+ return ret;
+}
+
+/*
+ * Structure used for data decompression.
+ */
+struct dec_data {
+ struct task_struct *thr; /* thread */
+ struct crypto_comp *cc; /* crypto compressor stream */
+ 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[UNC_SIZE]; /* uncompressed buffer */
+ unsigned char cmp[CMP_SIZE]; /* compressed buffer */
+};
+
+/*
+ * Decompression function that runs in its own thread.
+ */
+static int decompress_threadfn(void *data)
+{
+ struct dec_data *d = data;
+ unsigned int unc_len = 0;
+
+ while (1) {
+ wait_event(d->go, atomic_read_acquire(&d->ready) ||
+ kthread_should_stop());
+ if (kthread_should_stop()) {
+ d->thr = NULL;
+ d->ret = -1;
+ atomic_set_release(&d->stop, 1);
+ wake_up(&d->done);
+ break;
+ }
+ atomic_set(&d->ready, 0);
+
+ unc_len = UNC_SIZE;
+ d->ret = crypto_comp_decompress(d->cc, d->cmp + CMP_HEADER, d->cmp_len,
+ d->unc, &unc_len);
+ d->unc_len = unc_len;
+
+ if (clean_pages_on_decompress)
+ flush_icache_range((unsigned long)d->unc,
+ (unsigned long)d->unc + d->unc_len);
+
+ atomic_set_release(&d->stop, 1);
+ wake_up(&d->done);
+ }
+ return 0;
+}
+
+/**
+ * load_compressed_image - Load compressed image data and decompress it.
+ * @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_compressed_image(struct swap_map_handle *handle,
+ struct snapshot_handle *snapshot,
+ unsigned int nr_to_read)
+{
+ unsigned int m;
+ int ret = 0;
+ int eof = 0;
+ struct hib_bio_batch hb;
+ ktime_t start;
+ ktime_t 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;
+
+ hib_init_batch(&hb);
+
+ /*
+ * 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, CMP_THREADS);
+
+ page = vmalloc(array_size(CMP_MAX_RD_PAGES, sizeof(*page)));
+ if (!page) {
+ pr_err("Failed to allocate %s page\n", hib_comp_algo);
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+
+ data = vzalloc(array_size(nr_threads, sizeof(*data)));
+ if (!data) {
+ pr_err("Failed to allocate %s data\n", hib_comp_algo);
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+
+ crc = kzalloc(sizeof(*crc), GFP_KERNEL);
+ if (!crc) {
+ pr_err("Failed to allocate crc\n");
+ ret = -ENOMEM;
+ goto out_clean;
+ }
+
+ clean_pages_on_decompress = true;
+
+ /*
+ * 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].cc = crypto_alloc_comp(hib_comp_algo, 0, 0);
+ if (IS_ERR_OR_NULL(data[thr].cc)) {
+ pr_err("Could not allocate comp stream %ld\n", PTR_ERR(data[thr].cc));
+ ret = -EFAULT;
+ goto out_clean;
+ }
+
+ data[thr].thr = kthread_run(decompress_threadfn,
+ &data[thr],
+ "image_decompress/%u", thr);
+ if (IS_ERR(data[thr].thr)) {
+ data[thr].thr = NULL;
+ pr_err("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;
+ pr_err("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, CMP_MIN_RD_PAGES, CMP_MAX_RD_PAGES);
+
+ for (i = 0; i < read_pages; i++) {
+ page[i] = (void *)__get_free_page(i < CMP_PAGES ?
+ GFP_NOIO | __GFP_HIGH :
+ GFP_NOIO | __GFP_NOWARN |
+ __GFP_NORETRY);
+
+ if (!page[i]) {
+ if (i < CMP_PAGES) {
+ ring_size = i;
+ pr_err("Failed to allocate %s pages\n", hib_comp_algo);
+ ret = -ENOMEM;
+ goto out_clean;
+ } else {
+ break;
+ }
+ }
+ }
+ want = ring_size = i;
+
+ pr_info("Using %u thread(s) for %s decompression\n", nr_threads, hib_comp_algo);
+ pr_info("Loading and decompressing image data (%u pages)...\n",
+ nr_to_read);
+ m = nr_to_read / 10;
+ if (!m)
+ m = 1;
+ nr_pages = 0;
+ start = ktime_get();
+
+ 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], &hb);
+ 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_io(&hb);
+ if (ret)
+ goto out_finish;
+ have += asked;
+ asked = 0;
+ if (eof)
+ eof = 2;
+ }
+
+ if (crc->run_threads) {
+ wait_event(crc->done, atomic_read_acquire(&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 >
+ bytes_worst_compress(UNC_SIZE))) {
+ pr_err("Invalid %s compressed length\n", hib_comp_algo);
+ ret = -1;
+ goto out_finish;
+ }
+
+ need = DIV_ROUND_UP(data[thr].cmp_len + CMP_HEADER,
+ PAGE_SIZE);
+ if (need > have) {
+ if (eof > 1) {
+ ret = -1;
+ goto out_finish;
+ }
+ break;
+ }
+
+ for (off = 0;
+ off < CMP_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_release(&data[thr].ready, 1);
+ wake_up(&data[thr].go);
+ }
+
+ /*
+ * Wait for more data while we are decompressing.
+ */
+ if (have < CMP_PAGES && asked) {
+ ret = hib_wait_io(&hb);
+ 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_acquire(&data[thr].stop));
+ atomic_set(&data[thr].stop, 0);
+
+ ret = data[thr].ret;
+
+ if (ret < 0) {
+ pr_err("%s decompression failed\n", hib_comp_algo);
+ goto out_finish;
+ }
+
+ if (unlikely(!data[thr].unc_len ||
+ data[thr].unc_len > UNC_SIZE ||
+ data[thr].unc_len & (PAGE_SIZE - 1))) {
+ pr_err("Invalid %s uncompressed length\n", hib_comp_algo);
+ 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))
+ pr_info("Image loading progress: %3d%%\n",
+ nr_pages / m * 10);
+ nr_pages++;
+
+ ret = snapshot_write_next(snapshot);
+ if (ret <= 0) {
+ crc->run_threads = thr + 1;
+ atomic_set_release(&crc->ready, 1);
+ wake_up(&crc->go);
+ goto out_finish;
+ }
+ }
+ }
+
+ crc->run_threads = thr;
+ atomic_set_release(&crc->ready, 1);
+ wake_up(&crc->go);
+ }
+
+out_finish:
+ if (crc->run_threads) {
+ wait_event(crc->done, atomic_read_acquire(&crc->stop));
+ atomic_set(&crc->stop, 0);
+ }
+ stop = ktime_get();
+ if (!ret) {
+ pr_info("Image loading done\n");
+ ret = snapshot_write_finalize(snapshot);
+ if (!ret && !snapshot_image_loaded(snapshot))
+ ret = -ENODATA;
+ if (!ret) {
+ if (swsusp_header->flags & SF_CRC32_MODE) {
+ if(handle->crc32 != swsusp_header->crc32) {
+ pr_err("Invalid image CRC32!\n");
+ ret = -ENODATA;
+ }
+ }
+ }
+ }
+ swsusp_show_speed(start, stop, nr_to_read, "Read");
+out_clean:
+ hib_finish_batch(&hb);
+ 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);
+ if (data[thr].cc)
+ crypto_free_comp(data[thr].cc);
+ }
+ vfree(data);
+ }
+ 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 < (int)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_compressed_image(&handle, &snapshot, header->pages - 1);
+ }
+ swap_reader_finish(&handle);
+end:
+ if (!error)
+ pr_debug("Image successfully loaded\n");
+ else
+ pr_debug("Error %d resuming\n", error);
+ return error;
+}
+
+static void *swsusp_holder;
+
+/**
+ * swsusp_check - Open the resume device and check for the swsusp signature.
+ * @exclusive: Open the resume device exclusively.
+ */
+
+int swsusp_check(bool exclusive)
+{
+ void *holder = exclusive ? &swsusp_holder : NULL;
+ int error;
+
+ hib_resume_bdev_file = bdev_file_open_by_dev(swsusp_resume_device,
+ BLK_OPEN_READ, holder, NULL);
+ if (!IS_ERR(hib_resume_bdev_file)) {
+ set_blocksize(file_bdev(hib_resume_bdev_file), PAGE_SIZE);
+ clear_page(swsusp_header);
+ error = hib_submit_io(REQ_OP_READ, 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);
+ swsusp_header_flags = swsusp_header->flags;
+ /* Reset swap signature now */
+ error = hib_submit_io(REQ_OP_WRITE | REQ_SYNC,
+ swsusp_resume_block,
+ swsusp_header, NULL);
+ } else {
+ error = -EINVAL;
+ }
+ if (!error && swsusp_header->flags & SF_HW_SIG &&
+ swsusp_header->hw_sig != swsusp_hardware_signature) {
+ pr_info("Suspend image hardware signature mismatch (%08x now %08x); aborting resume.\n",
+ swsusp_header->hw_sig, swsusp_hardware_signature);
+ error = -EINVAL;
+ }
+
+put:
+ if (error)
+ fput(hib_resume_bdev_file);
+ else
+ pr_debug("Image signature found, resuming\n");
+ } else {
+ error = PTR_ERR(hib_resume_bdev_file);
+ }
+
+ if (error)
+ pr_debug("Image not found (code %d)\n", error);
+
+ return error;
+}
+
+/**
+ * swsusp_close - close resume device.
+ */
+
+void swsusp_close(void)
+{
+ if (IS_ERR(hib_resume_bdev_file)) {
+ pr_debug("Image device not initialised\n");
+ return;
+ }
+
+ fput(hib_resume_bdev_file);
+}
+
+/**
+ * swsusp_unmark - Unmark swsusp signature in the resume device
+ */
+
+#ifdef CONFIG_SUSPEND
+int swsusp_unmark(void)
+{
+ int error;
+
+ hib_submit_io(REQ_OP_READ, swsusp_resume_block,
+ swsusp_header, NULL);
+ if (!memcmp(HIBERNATE_SIG,swsusp_header->sig, 10)) {
+ memcpy(swsusp_header->sig,swsusp_header->orig_sig, 10);
+ error = hib_submit_io(REQ_OP_WRITE | REQ_SYNC,
+ swsusp_resume_block,
+ swsusp_header, NULL);
+ } else {
+ pr_err("Cannot find swsusp signature!\n");
+ error = -ENODEV;
+ }
+
+ /*
+ * We just returned from suspend, we don't need the image any more.
+ */
+ free_all_swap_pages(root_swap);
+
+ return error;
+}
+#endif
+
+static int __init 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);