diff options
Diffstat (limited to 'kernel/power/tuxonice_checksum.c')
| -rw-r--r-- | kernel/power/tuxonice_checksum.c | 392 |
1 files changed, 0 insertions, 392 deletions
diff --git a/kernel/power/tuxonice_checksum.c b/kernel/power/tuxonice_checksum.c deleted file mode 100644 index 1c4e10c72..000000000 --- a/kernel/power/tuxonice_checksum.c +++ /dev/null @@ -1,392 +0,0 @@ -/* - * kernel/power/tuxonice_checksum.c - * - * Copyright (C) 2006-2015 Nigel Cunningham (nigel at nigelcunningham com au) - * - * This file is released under the GPLv2. - * - * This file contains data checksum routines for TuxOnIce, - * using cryptoapi. They are used to locate any modifications - * made to pageset 2 while we're saving it. - */ - -#include <linux/suspend.h> -#include <linux/highmem.h> -#include <linux/vmalloc.h> -#include <linux/crypto.h> -#include <linux/scatterlist.h> - -#include "tuxonice.h" -#include "tuxonice_modules.h" -#include "tuxonice_sysfs.h" -#include "tuxonice_io.h" -#include "tuxonice_pageflags.h" -#include "tuxonice_checksum.h" -#include "tuxonice_pagedir.h" -#include "tuxonice_alloc.h" -#include "tuxonice_ui.h" - -static struct toi_module_ops toi_checksum_ops; - -/* Constant at the mo, but I might allow tuning later */ -static char toi_checksum_name[32] = "md4"; -/* Bytes per checksum */ -#define CHECKSUM_SIZE (16) - -#define CHECKSUMS_PER_PAGE ((PAGE_SIZE - sizeof(void *)) / CHECKSUM_SIZE) - -struct cpu_context { - struct crypto_hash *transform; - struct hash_desc desc; - struct scatterlist sg[2]; - char *buf; -}; - -static DEFINE_PER_CPU(struct cpu_context, contexts); -static int pages_allocated; -static unsigned long page_list; - -static int toi_num_resaved; - -static unsigned long this_checksum, next_page; -static int checksum_count; - -static inline int checksum_pages_needed(void) -{ - return DIV_ROUND_UP(pagedir2.size, CHECKSUMS_PER_PAGE); -} - -/* ---- Local buffer management ---- */ - -/* - * toi_checksum_cleanup - * - * Frees memory allocated for our labours. - */ -static void toi_checksum_cleanup(int ending_cycle) -{ - int cpu; - - if (ending_cycle) { - for_each_online_cpu(cpu) { - struct cpu_context *this = &per_cpu(contexts, cpu); - if (this->transform) { - crypto_free_hash(this->transform); - this->transform = NULL; - this->desc.tfm = NULL; - } - - if (this->buf) { - toi_free_page(27, (unsigned long) this->buf); - this->buf = NULL; - } - } - } -} - -/* - * toi_crypto_initialise - * - * Prepare to do some work by allocating buffers and transforms. - * Returns: Int: Zero. Even if we can't set up checksum, we still - * seek to hibernate. - */ -static int toi_checksum_initialise(int starting_cycle) -{ - int cpu; - - if (!(starting_cycle & SYSFS_HIBERNATE) || !toi_checksum_ops.enabled) - return 0; - - if (!*toi_checksum_name) { - printk(KERN_INFO "TuxOnIce: No checksum algorithm name set.\n"); - return 1; - } - - for_each_online_cpu(cpu) { - struct cpu_context *this = &per_cpu(contexts, cpu); - struct page *page; - - this->transform = crypto_alloc_hash(toi_checksum_name, 0, 0); - if (IS_ERR(this->transform)) { - printk(KERN_INFO "TuxOnIce: Failed to initialise the " - "%s checksum algorithm: %ld.\n", - toi_checksum_name, (long) this->transform); - this->transform = NULL; - return 1; - } - - this->desc.tfm = this->transform; - this->desc.flags = 0; - - page = toi_alloc_page(27, GFP_KERNEL); - if (!page) - return 1; - this->buf = page_address(page); - sg_init_one(&this->sg[0], this->buf, PAGE_SIZE); - } - return 0; -} - -/* - * toi_checksum_print_debug_stats - * @buffer: Pointer to a buffer into which the debug info will be printed. - * @size: Size of the buffer. - * - * Print information to be recorded for debugging purposes into a buffer. - * Returns: Number of characters written to the buffer. - */ - -static int toi_checksum_print_debug_stats(char *buffer, int size) -{ - int len; - - if (!toi_checksum_ops.enabled) - return scnprintf(buffer, size, - "- Checksumming disabled.\n"); - - len = scnprintf(buffer, size, "- Checksum method is '%s'.\n", - toi_checksum_name); - len += scnprintf(buffer + len, size - len, - " %d pages resaved in atomic copy.\n", toi_num_resaved); - return len; -} - -static int toi_checksum_memory_needed(void) -{ - return toi_checksum_ops.enabled ? - checksum_pages_needed() << PAGE_SHIFT : 0; -} - -static int toi_checksum_storage_needed(void) -{ - if (toi_checksum_ops.enabled) - return strlen(toi_checksum_name) + sizeof(int) + 1; - else - return 0; -} - -/* - * toi_checksum_save_config_info - * @buffer: Pointer to a buffer of size PAGE_SIZE. - * - * Save informaton needed when reloading the image at resume time. - * Returns: Number of bytes used for saving our data. - */ -static int toi_checksum_save_config_info(char *buffer) -{ - int namelen = strlen(toi_checksum_name) + 1; - int total_len; - - *((unsigned int *) buffer) = namelen; - strncpy(buffer + sizeof(unsigned int), toi_checksum_name, namelen); - total_len = sizeof(unsigned int) + namelen; - return total_len; -} - -/* toi_checksum_load_config_info - * @buffer: Pointer to the start of the data. - * @size: Number of bytes that were saved. - * - * Description: Reload information needed for dechecksuming the image at - * resume time. - */ -static void toi_checksum_load_config_info(char *buffer, int size) -{ - int namelen; - - namelen = *((unsigned int *) (buffer)); - strncpy(toi_checksum_name, buffer + sizeof(unsigned int), - namelen); - return; -} - -/* - * Free Checksum Memory - */ - -void free_checksum_pages(void) -{ - while (pages_allocated) { - unsigned long next = *((unsigned long *) page_list); - ClearPageNosave(virt_to_page(page_list)); - toi_free_page(15, (unsigned long) page_list); - page_list = next; - pages_allocated--; - } -} - -/* - * Allocate Checksum Memory - */ - -int allocate_checksum_pages(void) -{ - int pages_needed = checksum_pages_needed(); - - if (!toi_checksum_ops.enabled) - return 0; - - while (pages_allocated < pages_needed) { - unsigned long *new_page = - (unsigned long *) toi_get_zeroed_page(15, TOI_ATOMIC_GFP); - if (!new_page) { - printk(KERN_ERR "Unable to allocate checksum pages.\n"); - return -ENOMEM; - } - SetPageNosave(virt_to_page(new_page)); - (*new_page) = page_list; - page_list = (unsigned long) new_page; - pages_allocated++; - } - - next_page = (unsigned long) page_list; - checksum_count = 0; - - return 0; -} - -char *tuxonice_get_next_checksum(void) -{ - if (!toi_checksum_ops.enabled) - return NULL; - - if (checksum_count % CHECKSUMS_PER_PAGE) - this_checksum += CHECKSUM_SIZE; - else { - this_checksum = next_page + sizeof(void *); - next_page = *((unsigned long *) next_page); - } - - checksum_count++; - return (char *) this_checksum; -} - -int tuxonice_calc_checksum(struct page *page, char *checksum_locn) -{ - char *pa; - int result, cpu = smp_processor_id(); - struct cpu_context *ctx = &per_cpu(contexts, cpu); - - if (!toi_checksum_ops.enabled) - return 0; - - pa = kmap(page); - memcpy(ctx->buf, pa, PAGE_SIZE); - kunmap(page); - result = crypto_hash_digest(&ctx->desc, ctx->sg, PAGE_SIZE, - checksum_locn); - if (result) - printk(KERN_ERR "TuxOnIce checksumming: crypto_hash_digest " - "returned %d.\n", result); - return result; -} -/* - * Calculate checksums - */ - -void check_checksums(void) -{ - int index = 0, cpu = smp_processor_id(); - char current_checksum[CHECKSUM_SIZE]; - struct cpu_context *ctx = &per_cpu(contexts, cpu); - unsigned long pfn; - - if (!toi_checksum_ops.enabled) { - toi_message(TOI_IO, TOI_VERBOSE, 0, "Checksumming disabled."); - return; - } - - next_page = (unsigned long) page_list; - - toi_num_resaved = 0; - this_checksum = 0; - - toi_trace_index++; - - toi_message(TOI_IO, TOI_VERBOSE, 0, "Verifying checksums."); - memory_bm_position_reset(pageset2_map); - for (pfn = memory_bm_next_pfn(pageset2_map, 0); pfn != BM_END_OF_MAP; - pfn = memory_bm_next_pfn(pageset2_map, 0)) { - int ret, resave_needed = false; - char *pa; - struct page *page = pfn_to_page(pfn); - - if (index < checksum_count) { - if (index % CHECKSUMS_PER_PAGE) { - this_checksum += CHECKSUM_SIZE; - } else { - this_checksum = next_page + sizeof(void *); - next_page = *((unsigned long *) next_page); - } - - /* Done when IRQs disabled so must be atomic */ - pa = kmap_atomic(page); - memcpy(ctx->buf, pa, PAGE_SIZE); - kunmap_atomic(pa); - ret = crypto_hash_digest(&ctx->desc, ctx->sg, PAGE_SIZE, - current_checksum); - - if (ret) { - printk(KERN_INFO "Digest failed. Returned %d.\n", ret); - return; - } - - resave_needed = memcmp(current_checksum, (char *) this_checksum, - CHECKSUM_SIZE); - } else { - resave_needed = true; - } - - if (resave_needed) { - TOI_TRACE_DEBUG(pfn, "_Resaving %d", resave_needed); - SetPageResave(pfn_to_page(pfn)); - toi_num_resaved++; - if (test_action_state(TOI_ABORT_ON_RESAVE_NEEDED)) - set_abort_result(TOI_RESAVE_NEEDED); - } - - index++; - } - toi_message(TOI_IO, TOI_VERBOSE, 0, "Checksum verification complete."); -} - -static struct toi_sysfs_data sysfs_params[] = { - SYSFS_INT("enabled", SYSFS_RW, &toi_checksum_ops.enabled, 0, 1, 0, - NULL), - SYSFS_BIT("abort_if_resave_needed", SYSFS_RW, &toi_bkd.toi_action, - TOI_ABORT_ON_RESAVE_NEEDED, 0) -}; - -/* - * Ops structure. - */ -static struct toi_module_ops toi_checksum_ops = { - .type = MISC_MODULE, - .name = "checksumming", - .directory = "checksum", - .module = THIS_MODULE, - .initialise = toi_checksum_initialise, - .cleanup = toi_checksum_cleanup, - .print_debug_info = toi_checksum_print_debug_stats, - .save_config_info = toi_checksum_save_config_info, - .load_config_info = toi_checksum_load_config_info, - .memory_needed = toi_checksum_memory_needed, - .storage_needed = toi_checksum_storage_needed, - - .sysfs_data = sysfs_params, - .num_sysfs_entries = sizeof(sysfs_params) / - sizeof(struct toi_sysfs_data), -}; - -/* ---- Registration ---- */ -int toi_checksum_init(void) -{ - int result = toi_register_module(&toi_checksum_ops); - return result; -} - -void toi_checksum_exit(void) -{ - toi_unregister_module(&toi_checksum_ops); -} |