src/lib/cbfs.c - mirrors/cros/chromiumos/third_party/coreboot - Git at Google

 /*
  * This file is part of the coreboot project.
  *
  * Copyright (C) 2008, Jordan Crouse <jordan@cosmicpenguin.net>
  * Copyright (C) 2013 The Chromium OS Authors. All rights reserved.
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
  * the Free Software Foundation; version 2 of the License.
  *
  * This program is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  * GNU General Public License for more details.
  *
  * You should have received a copy of the GNU General Public License
  * along with this program; if not, write to the Free Software
  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
  */

 #ifdef LIBPAYLOAD
 # include <libpayload-config.h>
 # ifdef CONFIG_LZMA
 #  include <lzma.h>
 #  define CBFS_CORE_WITH_LZMA
 # endif
 # define CBFS_MINI_BUILD
 #elif defined(__SMM__)
 # define CBFS_MINI_BUILD
 #elif defined(__BOOT_BLOCK__)
   /* No LZMA in boot block. */
 #else
 # define CBFS_CORE_WITH_LZMA
 # include <lib.h>
 #endif

 #include <cbfs.h>
 #include <string.h>
 #include <cbmem.h>

 #ifdef LIBPAYLOAD
 # include <stdio.h>
 # define DEBUG(x...)
 # define LOG(x...) printf(x)
 # define ERROR(x...) printf(x)
 #else
 # include <console/console.h>
 # define ERROR(x...) printk(BIOS_ERR, "CBFS: " x)
 # define LOG(x...) printk(BIOS_INFO, "CBFS: " x)
 # if CONFIG_DEBUG_CBFS
 #  define DEBUG(x...) printk(BIOS_SPEW, "CBFS: " x)
 # else
 #  define DEBUG(x...)
 # endif
 #endif

 #if defined(CONFIG_CBFS_HEADER_ROM_OFFSET) && (CONFIG_CBFS_HEADER_ROM_OFFSET)
 # define CBFS_HEADER_ROM_ADDRESS (CONFIG_CBFS_HEADER_ROM_OFFSET)
 #else
 // Indirect address: only works on 32bit top-aligned systems.
 # define CBFS_HEADER_ROM_ADDRESS (*(uint32_t *)0xfffffffc)
 #endif

 #include "cbfs_core.c"

 #if CONFIG_VBOOT_VERIFY_FIRMWARE
 #include <vendorcode/google/chromeos/chromeos.h>
 #else
 static inline void *vboot_get_payload(int *len) { return NULL; }
 #endif

 #ifndef __SMM__
 static inline int tohex4(unsigned int c)
 {
 	return (c <= 9) ? (c + '0') : (c - 10 + 'a');
 }

 static void tohex16(unsigned int val, char* dest)
 {
 	dest[0] = tohex4(val>>12);
 	dest[1] = tohex4((val>>8) & 0xf);
 	dest[2] = tohex4((val>>4) & 0xf);
 	dest[3] = tohex4(val & 0xf);
 }

 void *cbfs_load_optionrom(struct cbfs_media *media, uint16_t vendor,
 			  uint16_t device, void *dest)
 {
 	char name[17] = "pciXXXX,XXXX.rom";
 	struct cbfs_optionrom *orom;
 	uint8_t *src;

 	tohex16(vendor, name+3);
 	tohex16(device, name+8);

 	orom = (struct cbfs_optionrom *)
 		cbfs_get_file_content(media, name, CBFS_TYPE_OPTIONROM);

 	if (orom == NULL)
 		return NULL;

 	/* They might have specified a dest address. If so, we can decompress.
 	 * If not, there's not much hope of decompressing or relocating the rom.
 	 * in the common case, the expansion rom is uncompressed, we
 	 * pass 0 in for the dest, and all we have to do is find the rom and
 	 * return a pointer to it.
 	 */

 	/* BUG: the cbfstool is (not yet) including a cbfs_optionrom header */
 	src = (uint8_t *)orom; // + sizeof(struct cbfs_optionrom);

 	if (! dest)
 		return src;

 	if (cbfs_decompress(ntohl(orom->compression),
 			     src,
 			     dest,
 			     ntohl(orom->len)))
 		return NULL;

 	return dest;
 }

 #if CONFIG_RELOCATABLE_RAMSTAGE && defined(__PRE_RAM__) && !defined(__BOOT_BLOCK__)

 #include <rmodule.h>
 #include <romstage_handoff.h>
 /* When CONFIG_RELOCATABLE_RAMSTAGE is enabled and this file is being compiled
  * for the romstage, the rmodule loader is used.  */
 void __attribute__((weak))
 cache_loaded_ramstage(struct romstage_handoff *handoff,
                       const struct cbmem_entry *ramstage, void *entry_point)
 {
 	uint32_t ramstage_size;
 	const struct cbmem_entry *entry;

 	if (handoff == NULL)
 		return;

 	ramstage_size = cbmem_entry_size(ramstage);
 	/* cbmem_entry_add() does a find() before add(). */
 	entry = cbmem_entry_add(CBMEM_ID_RAMSTAGE_CACHE, ramstage_size);

 	if (entry == NULL)
 		return;

 	/* Keep track of the entry point in the handoff structure. */
 	handoff->ramstage_entry_point = (uint32_t)entry_point;

 	memcpy(cbmem_entry_start(entry), cbmem_entry_start(ramstage),
 	       ramstage_size);
 }

 void * __attribute__((weak))
 load_cached_ramstage(struct romstage_handoff *handoff,
                      const struct cbmem_entry *ramstage)
 {
 	const struct cbmem_entry *entry_cache;

 	if (handoff == NULL)
 		return NULL;

 	entry_cache = cbmem_entry_find(CBMEM_ID_RAMSTAGE_CACHE);

 	if (entry_cache == NULL)
 		return NULL;

 	/* Load the cached ramstage copy into the to-be-run region. */
 	memcpy(cbmem_entry_start(ramstage), cbmem_entry_start(entry_cache),
 	       cbmem_entry_size(ramstage));

 	return (void *)handoff->ramstage_entry_point;
 }

 static void *load_stage_from_cbfs(struct cbfs_media *media, const char *name,
                                   struct romstage_handoff *handoff)
 {
 	struct cbfs_stage *stage;
 	struct rmodule ramstage;
 	void *entry_point;
 	size_t region_size;
 	char *ramstage_region;
 	int rmodule_offset;
 	int load_offset;
 	const struct cbmem_entry *ramstage_entry;

 	stage = (struct cbfs_stage *)
 		cbfs_get_file_content(media, name, CBFS_TYPE_STAGE);

 	if (stage == NULL)
 		return (void *) -1;

 	rmodule_offset =
 		rmodule_calc_region(DYN_CBMEM_ALIGN_SIZE,
 	                            stage->memlen, &region_size, &load_offset);

 	ramstage_entry = cbmem_entry_add(CBMEM_ID_RAMSTAGE, region_size);

 	if (ramstage_entry == NULL)
 		return (void *) -1;

 	ramstage_region = cbmem_entry_start(ramstage_entry);

 	LOG("Decompressing stage %s @ 0x%p (%d bytes)\n",
 	    name, &ramstage_region[rmodule_offset], stage->memlen);

 	if (cbfs_decompress(stage->compression, &stage[1],
 	                    &ramstage_region[rmodule_offset], stage->len))
 		return (void *) -1;

 	if (rmodule_parse(&ramstage_region[rmodule_offset], &ramstage))
 		return (void *) -1;

 	/* The ramstage is responsible for clearing its own bss. */
 	if (rmodule_load(&ramstage_region[load_offset], &ramstage))
 		return (void *) -1;

 	entry_point = rmodule_entry(&ramstage);

 	cache_loaded_ramstage(handoff, ramstage_entry, entry_point);

 	return entry_point;
 }

 void * cbfs_load_stage(struct cbfs_media *media, const char *name)
 {
 	struct romstage_handoff *handoff;
 	const struct cbmem_entry *ramstage;
 	void *entry;

 	handoff = romstage_handoff_find_or_add();

 	if (handoff == NULL) {
 		LOG("Couldn't find or allocate romstage handoff.\n");
 		return load_stage_from_cbfs(media, name, handoff);
 	} else if (!handoff->s3_resume)
 		return load_stage_from_cbfs(media, name, handoff);

 	ramstage = cbmem_entry_find(CBMEM_ID_RAMSTAGE);

 	if (ramstage == NULL)
 		return load_stage_from_cbfs(media, name, handoff);

 	/* S3 resume path. Load a cached copy of the loaded ramstage. If
 	 * return value is NULL load from cbfs. */
 	entry = load_cached_ramstage(handoff, ramstage);
 	if (entry == NULL)
 		return load_stage_from_cbfs(media, name, handoff);

 	return entry;
 }

 #else

 void * cbfs_load_stage(struct cbfs_media *media, const char *name)
 {
 	struct cbfs_stage *stage = (struct cbfs_stage *)
 		cbfs_get_file_content(media, name, CBFS_TYPE_STAGE);
 	/* this is a mess. There is no ntohll. */
 	/* for now, assume compatible byte order until we solve this. */
 	uint32_t entry;

 	if (stage == NULL)
 		return (void *) -1;

 	LOG("loading stage %s @ 0x%x (%d bytes), entry @ 0x%llx\n",
 			name,
 			(uint32_t) stage->load, stage->memlen,
 			stage->entry);
 	/* Stages rely the below clearing so that the bss is initialized. */
 	memset((void *) (uint32_t) stage->load, 0, stage->memlen);

 	if (cbfs_decompress(stage->compression,
 			     ((unsigned char *) stage) +
 			     sizeof(struct cbfs_stage),
 			     (void *) (uint32_t) stage->load,
 			     stage->len))
 		return (void *) -1;

 	DEBUG("stage loaded.\n");

 	entry = stage->entry;
 	// entry = ntohll(stage->entry);

 	return (void *) entry;
 }
 #endif /* CONFIG_RELOCATABLE_RAMSTAGE */

 int cbfs_execute_stage(struct cbfs_media *media, const char *name)
 {
 	struct cbfs_stage *stage = (struct cbfs_stage *)
 		cbfs_get_file_content(media, name, CBFS_TYPE_STAGE);

 	if (stage == NULL)
 		return 1;

 	if (ntohl(stage->compression) != CBFS_COMPRESS_NONE) {
 		LOG("Unable to run %s:  Compressed file"
 		       "Not supported for in-place execution\n", name);
 		return 1;
 	}

 	/* FIXME: This isn't right */
 	LOG("run @ %p\n", (void *) ntohl((uint32_t) stage->entry));
 	return run_address((void *)(uintptr_t)ntohll(stage->entry));
 }

 #if !CONFIG_ALT_CBFS_LOAD_PAYLOAD && !defined(__BOOT_BLOCK__)
 void *cbfs_load_payload(struct cbfs_media *media, const char *name)
 {
 	struct cbfs_payload *payload;

 	payload = vboot_get_payload(NULL);
 	if (payload != NULL)
 		return payload;

 	payload = (struct cbfs_payload *)cbfs_get_file_content(
 			media, name, CBFS_TYPE_PAYLOAD);
 	return payload;
 }
 #endif

 /* Simple buffer */

 void *cbfs_simple_buffer_map(struct cbfs_simple_buffer *buffer,
 			     struct cbfs_media *media,
 			     size_t offset, size_t count) {
 	void *address = buffer->buffer + buffer->allocated;;
 	DEBUG("simple_buffer_map(offset=%zd, count=%zd): "
 	      "allocated=%zd, size=%zd, last_allocate=%zd\n",
 	    offset, count, buffer->allocated, buffer->size,
 	    buffer->last_allocate);
 	if (buffer->allocated + count >= buffer->size)
 		return CBFS_MEDIA_INVALID_MAP_ADDRESS;
 	if (media->read(media, address, offset, count) != count) {
 		ERROR("simple_buffer: fail to read %zd bytes from 0x%zx\n",
 		      count, offset);
 		return CBFS_MEDIA_INVALID_MAP_ADDRESS;
 	}
 	buffer->allocated += count;
 	buffer->last_allocate = count;
 	return address;
 }

 void *cbfs_simple_buffer_unmap(struct cbfs_simple_buffer *buffer,
 			       const void *address) {
 	// TODO Add simple buffer management so we can free more than last
 	// allocated one.
 	DEBUG("simple_buffer_unmap(address=0x%p): "
 	      "allocated=%zd, size=%zd, last_allocate=%zd\n",
 	    address, buffer->allocated, buffer->size,
 	    buffer->last_allocate);
 	if ((buffer->buffer + buffer->allocated - buffer->last_allocate) ==
 	    address) {
 		buffer->allocated -= buffer->last_allocate;
 		buffer->last_allocate = 0;
 	}
 	return NULL;
 }

 /**
  * run_address is passed the address of a function taking no parameters and
  * jumps to it, returning the result.
  * @param f the address to call as a function.
  * @return value returned by the function.
  */

 int run_address(void *f)
 {
 	int (*v) (void);
 	v = f;
 	return v();
 }

 #endif
	/*
	* This file is part of the coreboot project.
	*
	* Copyright (C) 2008, Jordan Crouse <jordan@cosmicpenguin.net>
	* Copyright (C) 2013 The Chromium OS Authors. All rights reserved.
	*
	* This program is free software; you can redistribute it and/or modify
	* it under the terms of the GNU General Public License as published by
	* the Free Software Foundation; version 2 of the License.
	*
	* This program is distributed in the hope that it will be useful,
	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	* GNU General Public License for more details.
	*
	* You should have received a copy of the GNU General Public License
	* along with this program; if not, write to the Free Software
	* Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA, 02110-1301 USA
	*/

	#ifdef LIBPAYLOAD
	# include <libpayload-config.h>
	# ifdef CONFIG_LZMA
	# include <lzma.h>
	# define CBFS_CORE_WITH_LZMA
	# endif
	# define CBFS_MINI_BUILD
	#elif defined(__SMM__)
	# define CBFS_MINI_BUILD
	#elif defined(__BOOT_BLOCK__)
	/* No LZMA in boot block. */
	#else
	# define CBFS_CORE_WITH_LZMA
	# include <lib.h>
	#endif

	#include <cbfs.h>
	#include <string.h>
	#include <cbmem.h>

	#ifdef LIBPAYLOAD
	# include <stdio.h>
	# define DEBUG(x...)
	# define LOG(x...) printf(x)
	# define ERROR(x...) printf(x)
	#else
	# include <console/console.h>
	# define ERROR(x...) printk(BIOS_ERR, "CBFS: " x)
	# define LOG(x...) printk(BIOS_INFO, "CBFS: " x)
	# if CONFIG_DEBUG_CBFS
	# define DEBUG(x...) printk(BIOS_SPEW, "CBFS: " x)
	# else
	# define DEBUG(x...)
	# endif
	#endif

	#if defined(CONFIG_CBFS_HEADER_ROM_OFFSET) && (CONFIG_CBFS_HEADER_ROM_OFFSET)
	# define CBFS_HEADER_ROM_ADDRESS (CONFIG_CBFS_HEADER_ROM_OFFSET)
	#else
	// Indirect address: only works on 32bit top-aligned systems.
	# define CBFS_HEADER_ROM_ADDRESS ((uint32_t )0xfffffffc)
	#endif

	#include "cbfs_core.c"

	#if CONFIG_VBOOT_VERIFY_FIRMWARE
	#include <vendorcode/google/chromeos/chromeos.h>
	#else
	static inline void vboot_get_payload(int len) { return NULL; }
	#endif

	#ifndef __SMM__
	static inline int tohex4(unsigned int c)
	{
	return (c <= 9) ? (c + '0') : (c - 10 + 'a');
	}

	static void tohex16(unsigned int val, char* dest)
	{
	dest[0] = tohex4(val>>12);
	dest[1] = tohex4((val>>8) & 0xf);
	dest[2] = tohex4((val>>4) & 0xf);
	dest[3] = tohex4(val & 0xf);
	}

	void cbfs_load_optionrom(struct cbfs_media media, uint16_t vendor,
	uint16_t device, void *dest)
	{
	char name[17] = "pciXXXX,XXXX.rom";
	struct cbfs_optionrom *orom;
	uint8_t *src;

	tohex16(vendor, name+3);
	tohex16(device, name+8);

	orom = (struct cbfs_optionrom *)
	cbfs_get_file_content(media, name, CBFS_TYPE_OPTIONROM);

	if (orom == NULL)
	return NULL;

	/* They might have specified a dest address. If so, we can decompress.
	* If not, there's not much hope of decompressing or relocating the rom.
	* in the common case, the expansion rom is uncompressed, we
	* pass 0 in for the dest, and all we have to do is find the rom and
	* return a pointer to it.
	*/

	/* BUG: the cbfstool is (not yet) including a cbfs_optionrom header */
	src = (uint8_t *)orom; // + sizeof(struct cbfs_optionrom);

	if (! dest)
	return src;

	if (cbfs_decompress(ntohl(orom->compression),
	src,
	dest,
	ntohl(orom->len)))
	return NULL;

	return dest;
	}

	#if CONFIG_RELOCATABLE_RAMSTAGE && defined(__PRE_RAM__) && !defined(__BOOT_BLOCK__)

	#include <rmodule.h>
	#include <romstage_handoff.h>
	/* When CONFIG_RELOCATABLE_RAMSTAGE is enabled and this file is being compiled
	* for the romstage, the rmodule loader is used. */
	void __attribute__((weak))
	cache_loaded_ramstage(struct romstage_handoff *handoff,
	const struct cbmem_entry ramstage, void entry_point)
	{
	uint32_t ramstage_size;
	const struct cbmem_entry *entry;

	if (handoff == NULL)
	return;

	ramstage_size = cbmem_entry_size(ramstage);
	/* cbmem_entry_add() does a find() before add(). */
	entry = cbmem_entry_add(CBMEM_ID_RAMSTAGE_CACHE, ramstage_size);

	if (entry == NULL)
	return;

	/* Keep track of the entry point in the handoff structure. */
	handoff->ramstage_entry_point = (uint32_t)entry_point;

	memcpy(cbmem_entry_start(entry), cbmem_entry_start(ramstage),
	ramstage_size);
	}

	void * __attribute__((weak))
	load_cached_ramstage(struct romstage_handoff *handoff,
	const struct cbmem_entry *ramstage)
	{
	const struct cbmem_entry *entry_cache;

	if (handoff == NULL)
	return NULL;

	entry_cache = cbmem_entry_find(CBMEM_ID_RAMSTAGE_CACHE);

	if (entry_cache == NULL)
	return NULL;

	/* Load the cached ramstage copy into the to-be-run region. */
	memcpy(cbmem_entry_start(ramstage), cbmem_entry_start(entry_cache),
	cbmem_entry_size(ramstage));

	return (void *)handoff->ramstage_entry_point;
	}

	static void load_stage_from_cbfs(struct cbfs_media media, const char *name,
	struct romstage_handoff *handoff)
	{
	struct cbfs_stage *stage;
	struct rmodule ramstage;
	void *entry_point;
	size_t region_size;
	char *ramstage_region;
	int rmodule_offset;
	int load_offset;
	const struct cbmem_entry *ramstage_entry;

	stage = (struct cbfs_stage *)
	cbfs_get_file_content(media, name, CBFS_TYPE_STAGE);

	if (stage == NULL)
	return (void *) -1;

	rmodule_offset =
	rmodule_calc_region(DYN_CBMEM_ALIGN_SIZE,
	stage->memlen, &region_size, &load_offset);

	ramstage_entry = cbmem_entry_add(CBMEM_ID_RAMSTAGE, region_size);

	if (ramstage_entry == NULL)
	return (void *) -1;

	ramstage_region = cbmem_entry_start(ramstage_entry);

	LOG("Decompressing stage %s @ 0x%p (%d bytes)\n",
	name, &ramstage_region[rmodule_offset], stage->memlen);

	if (cbfs_decompress(stage->compression, &stage[1],
	&ramstage_region[rmodule_offset], stage->len))
	return (void *) -1;

	if (rmodule_parse(&ramstage_region[rmodule_offset], &ramstage))
	return (void *) -1;

	/* The ramstage is responsible for clearing its own bss. */
	if (rmodule_load(&ramstage_region[load_offset], &ramstage))
	return (void *) -1;

	entry_point = rmodule_entry(&ramstage);

	cache_loaded_ramstage(handoff, ramstage_entry, entry_point);

	return entry_point;
	}

	void * cbfs_load_stage(struct cbfs_media media, const char name)
	{
	struct romstage_handoff *handoff;
	const struct cbmem_entry *ramstage;
	void *entry;

	handoff = romstage_handoff_find_or_add();

	if (handoff == NULL) {
	LOG("Couldn't find or allocate romstage handoff.\n");
	return load_stage_from_cbfs(media, name, handoff);
	} else if (!handoff->s3_resume)
	return load_stage_from_cbfs(media, name, handoff);

	ramstage = cbmem_entry_find(CBMEM_ID_RAMSTAGE);

	if (ramstage == NULL)
	return load_stage_from_cbfs(media, name, handoff);

	/* S3 resume path. Load a cached copy of the loaded ramstage. If
	* return value is NULL load from cbfs. */
	entry = load_cached_ramstage(handoff, ramstage);
	if (entry == NULL)
	return load_stage_from_cbfs(media, name, handoff);

	return entry;
	}

	#else

	void * cbfs_load_stage(struct cbfs_media media, const char name)
	{
	struct cbfs_stage stage = (struct cbfs_stage )
	cbfs_get_file_content(media, name, CBFS_TYPE_STAGE);
	/* this is a mess. There is no ntohll. */
	/* for now, assume compatible byte order until we solve this. */
	uint32_t entry;

	if (stage == NULL)
	return (void *) -1;

	LOG("loading stage %s @ 0x%x (%d bytes), entry @ 0x%llx\n",
	name,
	(uint32_t) stage->load, stage->memlen,
	stage->entry);
	/* Stages rely the below clearing so that the bss is initialized. */
	memset((void *) (uint32_t) stage->load, 0, stage->memlen);

	if (cbfs_decompress(stage->compression,
	((unsigned char *) stage) +
	sizeof(struct cbfs_stage),
	(void *) (uint32_t) stage->load,
	stage->len))
	return (void *) -1;

	DEBUG("stage loaded.\n");

	entry = stage->entry;
	// entry = ntohll(stage->entry);

	return (void *) entry;
	}
	#endif /* CONFIG_RELOCATABLE_RAMSTAGE */

	int cbfs_execute_stage(struct cbfs_media media, const char name)
	{
	struct cbfs_stage stage = (struct cbfs_stage )
	cbfs_get_file_content(media, name, CBFS_TYPE_STAGE);

	if (stage == NULL)
	return 1;

	if (ntohl(stage->compression) != CBFS_COMPRESS_NONE) {
	LOG("Unable to run %s: Compressed file"
	"Not supported for in-place execution\n", name);
	return 1;
	}

	/* FIXME: This isn't right */
	LOG("run @ %p\n", (void *) ntohl((uint32_t) stage->entry));
	return run_address((void *)(uintptr_t)ntohll(stage->entry));
	}

	#if !CONFIG_ALT_CBFS_LOAD_PAYLOAD && !defined(__BOOT_BLOCK__)
	void cbfs_load_payload(struct cbfs_media media, const char *name)
	{
	struct cbfs_payload *payload;

	payload = vboot_get_payload(NULL);
	if (payload != NULL)
	return payload;

	payload = (struct cbfs_payload *)cbfs_get_file_content(
	media, name, CBFS_TYPE_PAYLOAD);
	return payload;
	}
	#endif

	/* Simple buffer */

	void cbfs_simple_buffer_map(struct cbfs_simple_buffer buffer,
	struct cbfs_media *media,
	size_t offset, size_t count) {
	void *address = buffer->buffer + buffer->allocated;;
	DEBUG("simple_buffer_map(offset=%zd, count=%zd): "
	"allocated=%zd, size=%zd, last_allocate=%zd\n",
	offset, count, buffer->allocated, buffer->size,
	buffer->last_allocate);
	if (buffer->allocated + count >= buffer->size)
	return CBFS_MEDIA_INVALID_MAP_ADDRESS;
	if (media->read(media, address, offset, count) != count) {
	ERROR("simple_buffer: fail to read %zd bytes from 0x%zx\n",
	count, offset);
	return CBFS_MEDIA_INVALID_MAP_ADDRESS;
	}
	buffer->allocated += count;
	buffer->last_allocate = count;
	return address;
	}

	void cbfs_simple_buffer_unmap(struct cbfs_simple_buffer buffer,
	const void *address) {
	// TODO Add simple buffer management so we can free more than last
	// allocated one.
	DEBUG("simple_buffer_unmap(address=0x%p): "
	"allocated=%zd, size=%zd, last_allocate=%zd\n",
	address, buffer->allocated, buffer->size,
	buffer->last_allocate);
	if ((buffer->buffer + buffer->allocated - buffer->last_allocate) ==
	address) {
	buffer->allocated -= buffer->last_allocate;
	buffer->last_allocate = 0;
	}
	return NULL;
	}

	/**
	* run_address is passed the address of a function taking no parameters and
	* jumps to it, returning the result.
	* @param f the address to call as a function.
	* @return value returned by the function.
	*/

	int run_address(void *f)
	{
	int (*v) (void);
	v = f;
	return v();
	}

	#endif