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-rw-r--r--kernel/power/tuxonice_prune.c406
1 files changed, 0 insertions, 406 deletions
diff --git a/kernel/power/tuxonice_prune.c b/kernel/power/tuxonice_prune.c
deleted file mode 100644
index 710e48dee..000000000
--- a/kernel/power/tuxonice_prune.c
+++ /dev/null
@@ -1,406 +0,0 @@
-/*
- * kernel/power/tuxonice_prune.c
- *
- * Copyright (C) 2012 Nigel Cunningham (nigel at nigelcunningham com au)
- *
- * This file is released under the GPLv2.
- *
- * This file implements a TuxOnIce module that seeks to prune the
- * amount of data written to disk. It builds a table of hashes
- * of the uncompressed data, and writes the pfn of the previous page
- * with the same contents instead of repeating the data when a match
- * is found.
- */
-
-#include <linux/suspend.h>
-#include <linux/highmem.h>
-#include <linux/vmalloc.h>
-#include <linux/crypto.h>
-#include <linux/scatterlist.h>
-#include <crypto/hash.h>
-
-#include "tuxonice_builtin.h"
-#include "tuxonice.h"
-#include "tuxonice_modules.h"
-#include "tuxonice_sysfs.h"
-#include "tuxonice_io.h"
-#include "tuxonice_ui.h"
-#include "tuxonice_alloc.h"
-
-/*
- * We never write a page bigger than PAGE_SIZE, so use a large number
- * to indicate that data is a PFN.
- */
-#define PRUNE_DATA_IS_PFN (PAGE_SIZE + 100)
-
-static unsigned long toi_pruned_pages;
-
-static struct toi_module_ops toi_prune_ops;
-static struct toi_module_ops *next_driver;
-
-static char toi_prune_hash_algo_name[32] = "sha1";
-
-static DEFINE_MUTEX(stats_lock);
-
-struct cpu_context {
- struct shash_desc desc;
- char *digest;
-};
-
-#define OUT_BUF_SIZE (2 * PAGE_SIZE)
-
-static DEFINE_PER_CPU(struct cpu_context, contexts);
-
-/*
- * toi_crypto_prepare
- *
- * Prepare to do some work by allocating buffers and transforms.
- */
-static int toi_prune_crypto_prepare(void)
-{
- int cpu, ret, digestsize;
-
- if (!*toi_prune_hash_algo_name) {
- printk(KERN_INFO "TuxOnIce: Pruning enabled but no "
- "hash algorithm set.\n");
- return 1;
- }
-
- for_each_online_cpu(cpu) {
- struct cpu_context *this = &per_cpu(contexts, cpu);
- this->desc.tfm = crypto_alloc_shash(toi_prune_hash_algo_name, 0, 0);
- if (IS_ERR(this->desc.tfm)) {
- printk(KERN_INFO "TuxOnIce: Failed to allocate the "
- "%s prune hash algorithm.\n",
- toi_prune_hash_algo_name);
- this->desc.tfm = NULL;
- return 1;
- }
-
- if (!digestsize)
- digestsize = crypto_shash_digestsize(this->desc.tfm);
-
- this->digest = kmalloc(digestsize, GFP_KERNEL);
- if (!this->digest) {
- printk(KERN_INFO "TuxOnIce: Failed to allocate space "
- "for digest output.\n");
- crypto_free_shash(this->desc.tfm);
- this->desc.tfm = NULL;
- }
-
- this->desc.flags = 0;
-
- ret = crypto_shash_init(&this->desc);
- if (ret < 0) {
- printk(KERN_INFO "TuxOnIce: Failed to initialise the "
- "%s prune hash algorithm.\n",
- toi_prune_hash_algo_name);
- kfree(this->digest);
- this->digest = NULL;
- crypto_free_shash(this->desc.tfm);
- this->desc.tfm = NULL;
- return 1;
- }
- }
-
- return 0;
-}
-
-static int toi_prune_rw_cleanup(int writing)
-{
- int cpu;
-
- for_each_online_cpu(cpu) {
- struct cpu_context *this = &per_cpu(contexts, cpu);
- if (this->desc.tfm) {
- crypto_free_shash(this->desc.tfm);
- this->desc.tfm = NULL;
- }
-
- if (this->digest) {
- kfree(this->digest);
- this->digest = NULL;
- }
- }
-
- return 0;
-}
-
-/*
- * toi_prune_init
- */
-
-static int toi_prune_init(int toi_or_resume)
-{
- if (!toi_or_resume)
- return 0;
-
- toi_pruned_pages = 0;
-
- next_driver = toi_get_next_filter(&toi_prune_ops);
-
- return next_driver ? 0 : -ECHILD;
-}
-
-/*
- * toi_prune_rw_init()
- */
-
-static int toi_prune_rw_init(int rw, int stream_number)
-{
- if (toi_prune_crypto_prepare()) {
- printk(KERN_ERR "Failed to initialise prune "
- "algorithm.\n");
- if (rw == READ) {
- printk(KERN_INFO "Unable to read the image.\n");
- return -ENODEV;
- } else {
- printk(KERN_INFO "Continuing without "
- "pruning the image.\n");
- toi_prune_ops.enabled = 0;
- }
- }
-
- return 0;
-}
-
-/*
- * toi_prune_write_page()
- *
- * Compress a page of data, buffering output and passing on filled
- * pages to the next module in the pipeline.
- *
- * Buffer_page: Pointer to a buffer of size PAGE_SIZE, containing
- * data to be checked.
- *
- * Returns: 0 on success. Otherwise the error is that returned by later
- * modules, -ECHILD if we have a broken pipeline or -EIO if
- * zlib errs.
- */
-static int toi_prune_write_page(unsigned long index, int buf_type,
- void *buffer_page, unsigned int buf_size)
-{
- int ret = 0, cpu = smp_processor_id(), write_data = 1;
- struct cpu_context *ctx = &per_cpu(contexts, cpu);
- u8* output_buffer = buffer_page;
- int output_len = buf_size;
- int out_buf_type = buf_type;
- void *buffer_start;
- u32 buf[4];
-
- if (ctx->desc.tfm) {
-
- buffer_start = TOI_MAP(buf_type, buffer_page);
- ctx->len = OUT_BUF_SIZE;
-
- ret = crypto_shash_digest(&ctx->desc, buffer_start, buf_size, &ctx->digest);
- if (ret) {
- printk(KERN_INFO "TuxOnIce: Failed to calculate digest (%d).\n", ret);
- } else {
- mutex_lock(&stats_lock);
-
- toi_pruned_pages++;
-
- mutex_unlock(&stats_lock);
-
- }
-
- TOI_UNMAP(buf_type, buffer_page);
- }
-
- if (write_data)
- ret = next_driver->write_page(index, out_buf_type,
- output_buffer, output_len);
- else
- ret = next_driver->write_page(index, out_buf_type,
- output_buffer, output_len);
-
- return ret;
-}
-
-/*
- * toi_prune_read_page()
- * @buffer_page: struct page *. Pointer to a buffer of size PAGE_SIZE.
- *
- * Retrieve data from later modules or from a previously loaded page and
- * fill the input buffer.
- * Zero if successful. Error condition from me or from downstream on failure.
- */
-static int toi_prune_read_page(unsigned long *index, int buf_type,
- void *buffer_page, unsigned int *buf_size)
-{
- int ret, cpu = smp_processor_id();
- unsigned int len;
- char *buffer_start;
- struct cpu_context *ctx = &per_cpu(contexts, cpu);
-
- if (!ctx->desc.tfm)
- return next_driver->read_page(index, TOI_PAGE, buffer_page,
- buf_size);
-
- /*
- * All our reads must be synchronous - we can't handle
- * data that hasn't been read yet.
- */
-
- ret = next_driver->read_page(index, buf_type, buffer_page, &len);
-
- if (len == PRUNE_DATA_IS_PFN) {
- buffer_start = kmap(buffer_page);
- }
-
- return ret;
-}
-
-/*
- * toi_prune_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_prune_print_debug_stats(char *buffer, int size)
-{
- int len;
-
- /* Output the number of pages pruned. */
- if (*toi_prune_hash_algo_name)
- len = scnprintf(buffer, size, "- Compressor is '%s'.\n",
- toi_prune_hash_algo_name);
- else
- len = scnprintf(buffer, size, "- Compressor is not set.\n");
-
- if (toi_pruned_pages)
- len += scnprintf(buffer+len, size - len, " Pruned "
- "%lu pages).\n",
- toi_pruned_pages);
- return len;
-}
-
-/*
- * toi_prune_memory_needed
- *
- * Tell the caller how much memory we need to operate during hibernate/resume.
- * Returns: Unsigned long. Maximum number of bytes of memory required for
- * operation.
- */
-static int toi_prune_memory_needed(void)
-{
- return 2 * PAGE_SIZE;
-}
-
-static int toi_prune_storage_needed(void)
-{
- return 2 * sizeof(unsigned long) + 2 * sizeof(int) +
- strlen(toi_prune_hash_algo_name) + 1;
-}
-
-/*
- * toi_prune_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_prune_save_config_info(char *buffer)
-{
- int len = strlen(toi_prune_hash_algo_name) + 1, offset = 0;
-
- *((unsigned long *) buffer) = toi_pruned_pages;
- offset += sizeof(unsigned long);
- *((int *) (buffer + offset)) = len;
- offset += sizeof(int);
- strncpy(buffer + offset, toi_prune_hash_algo_name, len);
- return offset + len;
-}
-
-/* toi_prune_load_config_info
- * @buffer: Pointer to the start of the data.
- * @size: Number of bytes that were saved.
- *
- * Description: Reload information needed for passing back to the
- * resumed kernel.
- */
-static void toi_prune_load_config_info(char *buffer, int size)
-{
- int len, offset = 0;
-
- toi_pruned_pages = *((unsigned long *) buffer);
- offset += sizeof(unsigned long);
- len = *((int *) (buffer + offset));
- offset += sizeof(int);
- strncpy(toi_prune_hash_algo_name, buffer + offset, len);
-}
-
-static void toi_prune_pre_atomic_restore(struct toi_boot_kernel_data *bkd)
-{
- bkd->pruned_pages = toi_pruned_pages;
-}
-
-static void toi_prune_post_atomic_restore(struct toi_boot_kernel_data *bkd)
-{
- toi_pruned_pages = bkd->pruned_pages;
-}
-
-/*
- * toi_expected_ratio
- *
- * Description: Returns the expected ratio between data passed into this module
- * and the amount of data output when writing.
- * Returns: 100 - we have no idea how many pages will be pruned.
- */
-
-static int toi_prune_expected_ratio(void)
-{
- return 100;
-}
-
-/*
- * data for our sysfs entries.
- */
-static struct toi_sysfs_data sysfs_params[] = {
- SYSFS_INT("enabled", SYSFS_RW, &toi_prune_ops.enabled, 0, 1, 0,
- NULL),
- SYSFS_STRING("algorithm", SYSFS_RW, toi_prune_hash_algo_name, 31, 0, NULL),
-};
-
-/*
- * Ops structure.
- */
-static struct toi_module_ops toi_prune_ops = {
- .type = FILTER_MODULE,
- .name = "prune",
- .directory = "prune",
- .module = THIS_MODULE,
- .initialise = toi_prune_init,
- .memory_needed = toi_prune_memory_needed,
- .print_debug_info = toi_prune_print_debug_stats,
- .save_config_info = toi_prune_save_config_info,
- .load_config_info = toi_prune_load_config_info,
- .storage_needed = toi_prune_storage_needed,
- .expected_compression = toi_prune_expected_ratio,
-
- .pre_atomic_restore = toi_prune_pre_atomic_restore,
- .post_atomic_restore = toi_prune_post_atomic_restore,
-
- .rw_init = toi_prune_rw_init,
- .rw_cleanup = toi_prune_rw_cleanup,
-
- .write_page = toi_prune_write_page,
- .read_page = toi_prune_read_page,
-
- .sysfs_data = sysfs_params,
- .num_sysfs_entries = sizeof(sysfs_params) /
- sizeof(struct toi_sysfs_data),
-};
-
-/* ---- Registration ---- */
-
-static __init int toi_prune_load(void)
-{
- return toi_register_module(&toi_prune_ops);
-}
-
-late_initcall(toi_prune_load);