| /* |
| * JFFS2 LZO Compression Interface. |
| * |
| * Copyright (C) 2007 Nokia Corporation. All rights reserved. |
| * |
| * Author: Richard Purdie <rpurdie@openedhand.com> |
| * |
| * This program is free software; you can redistribute it and/or |
| * modify it under the terms of the GNU General Public License |
| * version 2 as published by the Free Software Foundation. |
| * |
| * 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 |
| * |
| */ |
| |
| #include <stdint.h> |
| #include <stdio.h> |
| #include <string.h> |
| |
| #ifndef WITHOUT_LZO |
| #include <asm/types.h> |
| #include <linux/jffs2.h> |
| #include <lzo/lzo1x.h> |
| #include "compr.h" |
| |
| extern int page_size; |
| |
| static void *lzo_mem; |
| static void *lzo_compress_buf; |
| |
| /* |
| * Note about LZO compression. |
| * |
| * We want to use the _999_ compression routine which gives better compression |
| * rates at the expense of time. Decompression time is unaffected. We might as |
| * well use the standard lzo library routines for this but they will overflow |
| * the destination buffer since they don't check the destination size. |
| * |
| * We therefore compress to a temporary buffer and copy if it will fit. |
| * |
| */ |
| static int jffs2_lzo_cmpr(unsigned char *data_in, unsigned char *cpage_out, |
| uint32_t *sourcelen, uint32_t *dstlen) |
| { |
| lzo_uint compress_size; |
| int ret; |
| |
| ret = lzo1x_999_compress(data_in, *sourcelen, lzo_compress_buf, &compress_size, lzo_mem); |
| |
| if (ret != LZO_E_OK) |
| return -1; |
| |
| if (compress_size > *dstlen) |
| return -1; |
| |
| memcpy(cpage_out, lzo_compress_buf, compress_size); |
| *dstlen = compress_size; |
| |
| return 0; |
| } |
| |
| static int jffs2_lzo_decompress(unsigned char *data_in, unsigned char *cpage_out, |
| uint32_t srclen, uint32_t destlen) |
| { |
| int ret; |
| lzo_uint dl; |
| |
| ret = lzo1x_decompress_safe(data_in,srclen,cpage_out,&dl,NULL); |
| |
| if (ret != LZO_E_OK || dl != destlen) |
| return -1; |
| |
| return 0; |
| } |
| |
| static struct jffs2_compressor jffs2_lzo_comp = { |
| .priority = JFFS2_LZO_PRIORITY, |
| .name = "lzo", |
| .compr = JFFS2_COMPR_LZO, |
| .compress = &jffs2_lzo_cmpr, |
| .decompress = &jffs2_lzo_decompress, |
| .disabled = 1, |
| }; |
| |
| int jffs2_lzo_init(void) |
| { |
| int ret; |
| |
| lzo_mem = malloc(LZO1X_999_MEM_COMPRESS); |
| if (!lzo_mem) |
| return -1; |
| |
| /* Worse case LZO compression size from their FAQ */ |
| lzo_compress_buf = malloc(page_size + (page_size / 16) + 64 + 3); |
| if (!lzo_compress_buf) { |
| free(lzo_mem); |
| return -1; |
| } |
| |
| ret = jffs2_register_compressor(&jffs2_lzo_comp); |
| if (ret < 0) { |
| free(lzo_compress_buf); |
| free(lzo_mem); |
| } |
| |
| return ret; |
| } |
| |
| void jffs2_lzo_exit(void) |
| { |
| jffs2_unregister_compressor(&jffs2_lzo_comp); |
| free(lzo_compress_buf); |
| free(lzo_mem); |
| } |
| |
| #else |
| |
| int jffs2_lzo_init(void) |
| { |
| return 0; |
| } |
| |
| void jffs2_lzo_exit(void) |
| { |
| } |
| |
| #endif |