[PATCH] [30/48] Suspend2 2.1.9.8 for 2.6.12: 607-atomic-copy.patch

Nigel Cunningham
2005-07-06T03:11:22Z

diff -ruNp 608-compression.patch-old/kernel/power/suspend2_core/compression.c 608-compression.patch-new/kernel/power/suspend2_core/compression.c
--- 608-compression.patch-old/kernel/power/suspend2_core/compression.c 1970-01-01 10:00:00.000000000 +1000
+++ 608-compression.patch-new/kernel/power/suspend2_core/compression.c 2005-07-05 23:52:59.000000000 +1000
@@ -0,0 +1,636 @@
+/*
+ * kernel/power/suspend2_core/compression.c
+ *
+ * Copyright (C) 2003-2005 Nigel Cunningham <nigel@suspend2.net>
+ *
+ * This file is released under the GPLv2.
+ *
+ * This file contains data compression routines for suspend,
+ * using LZH compression.
+ *
+ */
+
+#include <linux/suspend.h>
+#include <linux/module.h>
+#include <linux/highmem.h>
+#include <linux/vmalloc.h>
+#include <linux/crypto.h>
+
+#include "suspend.h"
+#include "plugins.h"
+#include "proc.h"
+#include "suspend2_common.h"
+#include "utility.h"
+#include "io.h"
+
+#define S2C_WRITE 0
+#define S2C_READ 1
+
+static int s2_expected_compression = 0;
+
+static struct suspend_plugin_ops s2_compression_ops;
+static struct suspend_plugin_ops * next_driver;
+
+static char s2_compressor_name[32];
+static struct crypto_tfm * s2_compressor_transform;
+
+static u8 *local_buffer = NULL;
+static u8 *page_buffer = NULL;
+static unsigned int bufofs;
+
+static int position = 0;
+
+/* ---- Local buffer management ---- */
+
+/* allocate_local_buffer
+ *
+ * Description: Allocates a page of memory for buffering output.
+ * Returns: Int: Zero if successful, -ENONEM otherwise.
+ */
+
+static int allocate_local_buffer(void)
+{
+ if (!local_buffer) {
+ local_buffer = (char *) get_zeroed_page(GFP_ATOMIC);
+
+ if (!local_buffer) {
+ printk(KERN_ERR
+ "Failed to allocate the local buffer for "
+ "suspend2 compression driver.\n");
+ return -ENOMEM;
+ }
+ }
+
+ if (!page_buffer) {
+ page_buffer = (char *) get_zeroed_page(GFP_ATOMIC);
+
+ if (!page_buffer) {
+ printk(KERN_ERR
+ "Failed to allocate the page buffer for "
+ "suspend2 compression driver.\n");
+ return -ENOMEM;
+ }
+ }
+
+ return 0;
+}
+
+/* free_local_buffer
+ *
+ * Description: Frees memory allocated for buffering output.
+ */
+
+static inline void free_local_buffer(void)
+{
+ if (local_buffer)
+ free_pages((unsigned long) local_buffer, 0);
+
+ local_buffer = NULL;
+
+ if (page_buffer)
+ free_pages((unsigned long) page_buffer, 0);
+
+ page_buffer = NULL;
+}
+
+/* suspend2_crypto_cleanup
+ *
+ * Description: Frees memory allocated for our labours.
+ */
+
+static void suspend2_crypto_cleanup(void)
+{
+ if (s2_compressor_transform) {
+ crypto_free_tfm(s2_compressor_transform);
+ s2_compressor_transform = NULL;
+ }
+}
+
+/* suspend2_crypto_prepare
+ *
+ * Description: Prepare to do some work by allocating buffers and transforms.
+ * Returns: Int: Zero if successful, -ENONEM otherwise.
+ */
+
+static int s2_compress_crypto_prepare(int mode)
+{
+ if (!*s2_compressor_name) {
+ printk("Suspend2: Compression enabled but no compressor name set.\n");
+ return 1;
+ }
+
+ if (!(s2_compressor_transform = crypto_alloc_tfm(s2_compressor_name, 0))) {
+ printk("Suspend2: Failed to initialise the compression transform.\n");
+ return 1;
+ }
+
+ return 0;
+}
+
+/* ---- Exported functions ---- */
+
+/* write_init()
+ *
+ * Description: Allocate buffers and prepare to compress data.
+ * Arguments: Stream_number: Ignored.
+ * Returns: Zero on success, -ENOMEM if unable to vmalloc.
+ */
+
+static int s2_compress_write_init(int stream_number)
+{
+ int result;
+
+ next_driver = get_next_filter(&s2_compression_ops);
+
+ if (!next_driver) {
+ printk("Compression Driver: Argh! No one wants my output!");
+ return -ECHILD;
+ }
+
+ if ((result = s2_compress_crypto_prepare(S2C_WRITE))) {
+ return result;
+ }
+
+ if ((result = allocate_local_buffer()))
+ return result;
+
+ /* Only reset the stats if starting to write an image */
+ if (stream_number == 2)
+ bytes_in = bytes_out = 0;
+
+ bufofs = 0;
+
+ position = 0;
+
+ return 0;
+}
+
+/* s2_compress_write()
+ *
+ * Description: Helper function for write_chunk. Write the compressed data.
+ * Arguments: u8*: Output buffer to be written.
+ * unsigned int: Length of buffer.
+ * Return: int: Result to be passed back to caller.
+ */
+
+static int s2_compress_write (u8 *buffer, unsigned int len)
+{
+ int ret;
+
+ bytes_out += len;
+
+ while (len + bufofs > PAGE_SIZE) {
+ unsigned int chunk = PAGE_SIZE - bufofs;
+ memcpy (local_buffer + bufofs, buffer, chunk);
+ buffer += chunk;
+ len -= chunk;
+ bufofs = 0;
+ if ((ret = next_driver->ops.filter.write_chunk(virt_to_page(local_buffer))) < 0)
+ return ret;
+ }
+ memcpy (local_buffer + bufofs, buffer, len);
+ bufofs += len;
+ return 0;
+}
+
+/* s2_compress_write_chunk()
+ *
+ * Description: Compress a page of data, buffering output and passing on
+ * filled pages to the next plugin in the pipeline.
+ * Arguments: Buffer_page: Pointer to a buffer of size PAGE_SIZE,
+ * containing data to be compressed.
+ * Returns: 0 on success. Otherwise the error is that returned by later
+ * plugins, -ECHILD if we have a broken pipeline or -EIO if
+ * zlib errs.
+ */
+
+static int s2_compress_write_chunk(struct page * buffer_page)
+{
+ int ret;
+ unsigned int len;
+ u16 len_written;
+ char * buffer_start;
+
+ if (!s2_compressor_transform)
+ return next_driver->ops.filter.write_chunk(buffer_page);
+
+ buffer_start = kmap(buffer_page);
+
+ bytes_in += PAGE_SIZE;
+
+ len = PAGE_SIZE;
+
+ ret = crypto_comp_compress(s2_compressor_transform,
+ buffer_start, PAGE_SIZE,
+ page_buffer, &len);
+
+ if (ret) {
+ printk("Compression failed.\n");
+ goto failure;
+ }
+
+ len_written = (u16) len;
+
+ if ((ret = s2_compress_write((u8 *)&len_written, 2)) >= 0) {
+ if ((ret = s2_compress_write((u8 *) &position, sizeof(position))))
+ return -EIO;
+ if (len < PAGE_SIZE) { // some compression
+ position += len;
+ ret = s2_compress_write(page_buffer, len);
+ } else {
+ ret = s2_compress_write(buffer_start, PAGE_SIZE);
+ position += PAGE_SIZE;
+ }
+ }
+ position += 2 + sizeof(int);
+
+
+failure:
+ kunmap(buffer_page);
+ return ret;
+}
+
+/* write_cleanup()
+ *
+ * Description: Write unflushed data and free workspace.
+ * Returns: Result of writing last page.
+ */
+
+static int s2_compress_write_cleanup(void)
+{
+ int ret = 0;
+
+ if (s2_compressor_transform)
+ ret = next_driver->ops.filter.write_chunk(virt_to_page(local_buffer));
+
+ suspend2_crypto_cleanup();
+ free_local_buffer();
+
+ return ret;
+}
+
+/* read_init()
+ *
+ * Description: Prepare to read a new stream of data.
+ * Arguments: int: Section of image about to be read.
+ * Returns: int: Zero on success, error number otherwise.
+ */
+
+static int s2_compress_read_init(int stream_number)
+{
+ int result;
+
+ next_driver = get_next_filter(&s2_compression_ops);
+
+ if (!next_driver) {
+ printk("Compression Driver: Argh! No one wants "
+ "to feed me data!");
+ return -ECHILD;
+ }
+
+ if ((result = s2_compress_crypto_prepare(S2C_READ)))
+ return result;
+
+ if ((result = allocate_local_buffer()))
+ return result;
+
+ bufofs = PAGE_SIZE;
+
+ position = 0;
+
+ return 0;
+}
+
+/* s2_compress_read()
+ *
+ * Description: Read data into compression buffer.
+ * Arguments: u8 *: Address of the buffer.
+ * unsigned int: Length
+ * Returns: int: Result of reading the image chunk.
+ */
+
+static int s2_compress_read (u8 * buffer, unsigned int len)
+{
+ int ret;
+
+ while (len + bufofs > PAGE_SIZE) {
+ unsigned int chunk = PAGE_SIZE - bufofs;
+ memcpy(buffer, local_buffer + bufofs, chunk);
+ buffer += chunk;
+ len -= chunk;
+ bufofs = 0;
+ if ((ret = next_driver->ops.filter.read_chunk(
+ virt_to_page(local_buffer), SUSPEND_SYNC)) < 0) {
+ return ret;
+ }
+ }
+ memcpy (buffer, local_buffer + bufofs, len);
+ bufofs += len;
+ return 0;
+}
+
+/* s2_compress_read_chunk()
+ *
+ * Description: Retrieve data from later plugins and decompress it until the
+ * input buffer is filled.
+ * Arguments: Buffer_start: Pointer to a buffer of size PAGE_SIZE.
+ * Sync: Whether the previous plugin (or core) wants its
+ * data synchronously.
+ * Returns: Zero if successful. Error condition from me or from downstream
+ * on failure.
+ */
+
+static int s2_compress_read_chunk(struct page * buffer_page, int sync)
+{
+ int ret, position_saved;
+ unsigned int len;
+ u16 len_written;
+ char * buffer_start;
+
+ if (!s2_compressor_transform)
+ return next_driver->ops.filter.read_chunk(buffer_page, SUSPEND_ASYNC);
+
+ /*
+ * All our reads must be synchronous - we can't decompress
+ * data that hasn't been read yet.
+ */
+
+ buffer_start = kmap(buffer_page);
+
+ if ((ret = s2_compress_read ((u8 *)&len_written, 2)) >= 0) {
+ len = (unsigned int) len_written;
+ ret = s2_compress_read((u8 *) &position_saved, sizeof(position_saved));
+ if (ret)
+ return ret;
+
+ if (position != position_saved) {
+ printk("Position saved (%d) != position I'm at now (%d).\n",
+ position_saved, position);
+ BUG_ON(1);
+ }
+ if (len >= PAGE_SIZE) { // uncompressed
+ ret = s2_compress_read(buffer_start, PAGE_SIZE);
+ if (ret)
+ return ret;
+
+ position += PAGE_SIZE;
+ } else { // compressed
+ if ((ret = s2_compress_read(page_buffer, len)) >= 0) {
+ int outlen = PAGE_SIZE;
+ /* Important note.
+ *
+ * For Deflate, decompression return values may represent
+ * errors. Deflate complains when everything is alright, so
+ * we ignore the errors unless the number of output bytes is
+ * not PAGE_SIZE.
+ */
+ crypto_comp_decompress(s2_compressor_transform,
+ page_buffer, len,
+ buffer_start, &outlen);
+ if (outlen != PAGE_SIZE) {
+ printk("Decompression yielded %ld bytes instead of %d.\n", PAGE_SIZE, outlen);
+ ret = -EIO;
+ } else
+ ret = 0;
+ }
+ position += len;
+ }
+ position += 2 + sizeof(int);
+ } else
+ printk("Compress_read returned %d.", ret);
+ kunmap(buffer_page);
+ return ret;
+}
+
+/* read_cleanup()
+ *
+ * Description: Clean up after reading part or all of a stream of data.
+ * Returns: int: Always zero. Never fails.
+ */
+
+static int s2_compress_read_cleanup(void)
+{
+ suspend2_crypto_cleanup();
+ free_local_buffer();
+ return 0;
+}
+
+/* s2_compress_print_debug_stats
+ *
+ * Description: Print information to be recorded for debugging purposes into a
+ * buffer.
+ * Arguments: buffer: Pointer to a buffer into which the debug info will be
+ * printed.
+ * size: Size of the buffer.
+ * Returns: Number of characters written to the buffer.
+ */
+
+static int s2_compress_print_debug_stats(char * buffer, int size)
+{
+ int pages_in = bytes_in >> PAGE_SHIFT,
+ pages_out = bytes_out >> PAGE_SHIFT;
+ int len;
+
+ /* Output the compression ratio achieved. */
+ len = suspend_snprintf(buffer, size, "- Compressor %s enabled.\n",
+ s2_compressor_name);
+ if (pages_in)
+ len+= suspend_snprintf(buffer+len, size - len,
+ " Compressed %ld bytes into %ld (%d percent compression).\n",
+ bytes_in, bytes_out, (pages_in - pages_out) * 100 / pages_in);
+ return len;
+}
+
+/* compression_memory_needed
+ *
+ * Description: Tell the caller how much memory we need to operate during
+ * suspend/resume.
+ * Returns: Unsigned long. Maximum number of bytes of memory required for
+ * operation.
+ */
+
+static unsigned long s2_compress_memory_needed(void)
+{
+ return PAGE_SIZE;
+}
+
+static unsigned long s2_compress_storage_needed(void)
+{
+ return 2 * sizeof(unsigned long) + sizeof(int);
+}
+
+/* s2_compress_save_config_info
+ *
+ * Description: Save informaton needed when reloading the image at resume time.
+ * Arguments: Buffer: Pointer to a buffer of size PAGE_SIZE.
+ * Returns: Number of bytes used for saving our data.
+ */
+
+static int s2_compress_save_config_info(char * buffer)
+{
+ int namelen = strlen(s2_compressor_name) + 1;
+ int total_len;
+
+ *((unsigned long *) buffer) = bytes_in;
+ *((unsigned long *) (buffer + sizeof(unsigned long))) = bytes_out;
+ *((int *) (buffer + 2 * sizeof(unsigned long))) = s2_expected_compression;
+ *((int *) (buffer + 3 * sizeof(unsigned long))) = namelen;
+ strncpy(buffer + 4 * sizeof(unsigned long), s2_compressor_name, namelen);
+ total_len = 2 * sizeof(unsigned long) + 2 * sizeof(int) + namelen;
+ return total_len;
+}
+
+/* s2_compress_load_config_info
+ *
+ * Description: Reload information needed for decompressing the image at
+ * resume time.
+ * Arguments: Buffer: Pointer to the start of the data.
+ * Size: Number of bytes that were saved.
+ */
+
+static void s2_compress_load_config_info(char * buffer, int size)
+{
+ int namelen;
+
+ bytes_in = *((unsigned long *) buffer);
+ bytes_out = *((unsigned long *) (buffer + sizeof(unsigned long)));
+ s2_expected_compression = *((int *) (buffer + 2 * sizeof(unsigned long)));
+ namelen = *((int *) (buffer + 3 * sizeof(unsigned long)));
+ strncpy(s2_compressor_name, buffer + 4 * sizeof(unsigned long), namelen);
+ return;
+}
+
+/* s2_compress_get_expected_compression
+ *
+ * Description: Returns the expected ratio between data passed into this plugin
+ * and the amount of data output when writing.
+ * Returns: 100 if the plugin is disabled. Otherwise the value set by the
+ * user via our proc entry.
+ */
+
+static int s2_compress_get_expected_compression(void)
+{
+ return 100 - s2_expected_compression;
+}
+
+static void s2_compressor_disable_if_empty(void)
+{
+ s2_compression_ops.disabled = !(*s2_compressor_name);
+}
+
+static int s2_compress_initialise(int starting_cycle)
+{
+ if (starting_cycle)
+ s2_compressor_disable_if_empty();
+
+ return 0;
+}
+/*
+ * data for our proc entries.
+ */
+
+static struct suspend_proc_data proc_params[] = {
+ {
+ .filename = "expected_compression",
+ .permissions = PROC_RW,
+ .type = SUSPEND_PROC_DATA_INTEGER,
+ .data = {
+ .integer = {
+ .variable = &s2_expected_compression,
+ .minimum = 0,
+ .maximum = 99,
+ }
+ }
+ },
+
+ {
+ .filename = "disable_compression",
+ .permissions = PROC_RW,
+ .type = SUSPEND_PROC_DATA_INTEGER,
+ .data = {
+ .integer = {
+ .variable = &s2_compression_ops.disabled,
+ .minimum = 0,
+ .maximum = 1,
+ }
+ }
+ },
+
+ {
+ .filename = "compressor",
+ .permissions = PROC_RW,
+ .type = SUSPEND_PROC_DATA_STRING,
+ .data = {
+ .string = {
+ .variable = s2_compressor_name,
+ .max_length = 31,
+ }
+ },
+ .write_proc = &s2_compressor_disable_if_empty,
+ }
+};
+
+/*
+ * Ops structure.
+ */
+
+static struct suspend_plugin_ops s2_compression_ops = {
+ .type = FILTER_PLUGIN,
+ .name = "Suspend2 Compressor",
+ .module = THIS_MODULE,
+ .memory_needed = s2_compress_memory_needed,
+ .print_debug_info = s2_compress_print_debug_stats,
+ .save_config_info = s2_compress_save_config_info,
+ .load_config_info = s2_compress_load_config_info,
+ .storage_needed = s2_compress_storage_needed,
+
+ .initialise = s2_compress_initialise,
+
+ .write_init = s2_compress_write_init,
+ .write_cleanup = s2_compress_write_cleanup,
+ .read_init = s2_compress_read_init,
+ .read_cleanup = s2_compress_read_cleanup,
+
+ .ops = {
+ .filter = {
+ .write_chunk = s2_compress_write_chunk,
+ .read_chunk = s2_compress_read_chunk,
+ .expected_compression = s2_compress_get_expected_compression,
+ }
+ }
+};
+
+/* ---- Registration ---- */
+
+static __init int s2_compress_load(void)
+{
+ int result;
+ int i, numfiles = sizeof(proc_params) / sizeof(struct suspend_proc_data);
+
+ printk("Software Suspend Compression Driver loading.\n");
+ if (!(result = suspend_register_plugin(&s2_compression_ops))) {
+ for (i=0; i< numfiles; i++)
+ suspend_register_procfile(&proc_params[i]);
+ } else
+ printk("Software Suspend Compression Driver unable to register!\n");
+ return result;
+}
+
+#ifdef MODULE
+static __exit void s2_compress_unload(void)
+{
+ printk("Software Suspend Compression Driver unloading.\n");
+ for (i=0; i< numfiles; i++)
+ suspend_unregister_procfile(&proc_params[i]);
+ suspend_unregister_plugin(&s2_compression_ops);
+}
+
+
+module_init(s2_compress_load);
+module_exit(s2_compress_unload);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Nigel Cunningham");
+MODULE_DESCRIPTION("Compression Support for Suspend2");
+#else
+late_initcall(s2_compress_load);
+#endif