diff options
Diffstat (limited to 'packages/mtd/mtd-utils/favour_lzo.patch')
| -rw-r--r-- | packages/mtd/mtd-utils/favour_lzo.patch | 136 |
1 files changed, 136 insertions, 0 deletions
diff --git a/packages/mtd/mtd-utils/favour_lzo.patch b/packages/mtd/mtd-utils/favour_lzo.patch new file mode 100644 index 0000000000..9e55d5f4b3 --- /dev/null +++ b/packages/mtd/mtd-utils/favour_lzo.patch @@ -0,0 +1,136 @@ +Add a favourlzo compression mode to mtd-utils + +This allows lzo compression to be used in the cases where the +compression ratio isn't quite as good zlib. This can make sense in +certain use cases because LZO decompression is much faster than zlib. + +Signed-off-by: Richard Purdie <rpurdie@openedhand.com> + +--- + compr.c | 52 +++++++++++++++++++++++++++++++++++++++++++++++++--- + compr.h | 1 + + 2 files changed, 50 insertions(+), 3 deletions(-) + +Index: git/compr.c +=================================================================== +--- git.orig/compr.c 2007-03-01 11:58:01.000000000 +0000 ++++ git/compr.c 2007-03-01 11:58:09.000000000 +0000 +@@ -16,6 +16,8 @@ + #include <stdlib.h> + #include <linux/jffs2.h> + ++#define FAVOUR_LZO_PERCENT 80 ++ + extern int page_size; + + /* LIST IMPLEMENTATION (from linux/list.h) */ +@@ -166,6 +168,33 @@ static void jffs2_decompression_test(str + } + } + ++/* ++ * Return 1 to use this compression ++ */ ++static int jffs2_is_best_compression(struct jffs2_compressor *this, ++ struct jffs2_compressor *best, uint32_t size, uint32_t bestsize) ++{ ++ switch (jffs2_compression_mode) { ++ case JFFS2_COMPR_MODE_SIZE: ++ if (bestsize > size) ++ return 1; ++ return 0; ++ case JFFS2_COMPR_MODE_FAVOURLZO: ++ if ((this->compr == JFFS2_COMPR_LZO) && (bestsize > size)) ++ return 1; ++ if ((best->compr != JFFS2_COMPR_LZO) && (bestsize > size)) ++ return 1; ++ if ((this->compr == JFFS2_COMPR_LZO) && (bestsize > (size * FAVOUR_LZO_PERCENT / 100))) ++ return 1; ++ if ((bestsize * FAVOUR_LZO_PERCENT / 100) > size) ++ return 1; ++ ++ return 0; ++ } ++ /* Shouldn't happen */ ++ return 0; ++} ++ + /* jffs2_compress: + * @data: Pointer to uncompressed data + * @cdata: Pointer to returned pointer to buffer for compressed data +@@ -231,21 +260,29 @@ uint16_t jffs2_compress( unsigned char * + } + if (ret == JFFS2_COMPR_NONE) free(output_buf); + break; ++ case JFFS2_COMPR_MODE_FAVOURLZO: + case JFFS2_COMPR_MODE_SIZE: + orig_slen = *datalen; + orig_dlen = *cdatalen; + list_for_each_entry(this, &jffs2_compressor_list, list) { ++ uint32_t needed_buf_size; ++ ++ if (jffs2_compression_mode == JFFS2_COMPR_MODE_FAVOURLZO) ++ needed_buf_size = orig_slen+jffs2_compression_check; ++ else ++ needed_buf_size = orig_dlen+jffs2_compression_check; ++ + /* Skip decompress-only backwards-compatibility and disabled modules */ + if ((!this->compress)||(this->disabled)) + continue; + /* Allocating memory for output buffer if necessary */ +- if ((this->compr_buf_size<orig_dlen+jffs2_compression_check)&&(this->compr_buf)) { ++ if ((this->compr_buf_size < needed_buf_size) && (this->compr_buf)) { + free(this->compr_buf); + this->compr_buf_size=0; + this->compr_buf=NULL; + } + if (!this->compr_buf) { +- tmp_buf = malloc(orig_dlen+jffs2_compression_check); ++ tmp_buf = malloc(needed_buf_size); + if (!tmp_buf) { + fprintf(stderr,"mkfs.jffs2: No memory for compressor allocation. (%d bytes)\n",orig_dlen); + continue; +@@ -265,7 +302,8 @@ uint16_t jffs2_compress( unsigned char * + if (!compr_ret) { + if (jffs2_compression_check) + jffs2_decompression_test(this, data_in, this->compr_buf, *cdatalen, *datalen, this->compr_buf_size); +- if ((!best_dlen)||(best_dlen>*cdatalen)) { ++ if (((!best_dlen) || jffs2_is_best_compression(this, best, *cdatalen, best_dlen)) ++ && (*cdatalen < *datalen)) { + best_dlen = *cdatalen; + best_slen = *datalen; + best = this; +@@ -377,6 +415,9 @@ char *jffs2_stats(void) + case JFFS2_COMPR_MODE_SIZE: + act_buf += sprintf(act_buf,"size"); + break; ++ case JFFS2_COMPR_MODE_FAVOURLZO: ++ act_buf += sprintf(act_buf,"favourlzo"); ++ break; + default: + act_buf += sprintf(act_buf,"unkown"); + break; +@@ -413,6 +454,11 @@ int jffs2_set_compression_mode_name(cons + jffs2_compression_mode = JFFS2_COMPR_MODE_SIZE; + return 0; + } ++ if (!strcmp("favourlzo", name)) { ++ jffs2_compression_mode = JFFS2_COMPR_MODE_FAVOURLZO; ++ return 0; ++ } ++ + return 1; + } + +Index: git/compr.h +=================================================================== +--- git.orig/compr.h 2007-03-01 11:58:01.000000000 +0000 ++++ git/compr.h 2007-03-01 11:58:09.000000000 +0000 +@@ -32,6 +32,7 @@ + #define JFFS2_COMPR_MODE_NONE 0 + #define JFFS2_COMPR_MODE_PRIORITY 1 + #define JFFS2_COMPR_MODE_SIZE 2 ++#define JFFS2_COMPR_MODE_FAVOURLZO 3 + + #define kmalloc(a,b) malloc(a) + #define kfree(a) free(a) |