diff options
Diffstat (limited to 'fs/jffs2/compr.c')
-rw-r--r-- | fs/jffs2/compr.c | 422 |
1 files changed, 232 insertions, 190 deletions
diff --git a/fs/jffs2/compr.c b/fs/jffs2/compr.c index 485d065de41..86739ee53b3 100644 --- a/fs/jffs2/compr.c +++ b/fs/jffs2/compr.c @@ -5,7 +5,7 @@ * Created by Arjan van de Ven <arjanv@redhat.com> * * Copyright © 2004 Ferenc Havasi <havasi@inf.u-szeged.hu>, - * University of Szeged, Hungary + * University of Szeged, Hungary * * For licensing information, see the file 'LICENCE' in this directory. * @@ -24,6 +24,34 @@ static int jffs2_compression_mode = JFFS2_COMPR_MODE_PRIORITY; /* Statistics for blocks stored without compression */ static uint32_t none_stat_compr_blocks=0,none_stat_decompr_blocks=0,none_stat_compr_size=0; + +/* + * 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 @@ -43,121 +71,124 @@ static uint32_t none_stat_compr_blocks=0,none_stat_decompr_blocks=0,none_stat_co * *datalen accordingly to show the amount of data which were compressed. */ uint16_t jffs2_compress(struct jffs2_sb_info *c, struct jffs2_inode_info *f, - unsigned char *data_in, unsigned char **cpage_out, - uint32_t *datalen, uint32_t *cdatalen) + unsigned char *data_in, unsigned char **cpage_out, + uint32_t *datalen, uint32_t *cdatalen) { int ret = JFFS2_COMPR_NONE; - int compr_ret; - struct jffs2_compressor *this, *best=NULL; - unsigned char *output_buf = NULL, *tmp_buf; - uint32_t orig_slen, orig_dlen; - uint32_t best_slen=0, best_dlen=0; + int compr_ret; + struct jffs2_compressor *this, *best=NULL; + unsigned char *output_buf = NULL, *tmp_buf; + uint32_t orig_slen, orig_dlen; + uint32_t best_slen=0, best_dlen=0; - switch (jffs2_compression_mode) { - case JFFS2_COMPR_MODE_NONE: - break; - case JFFS2_COMPR_MODE_PRIORITY: - output_buf = kmalloc(*cdatalen,GFP_KERNEL); - if (!output_buf) { - printk(KERN_WARNING "JFFS2: No memory for compressor allocation. Compression failed.\n"); - goto out; - } - orig_slen = *datalen; - orig_dlen = *cdatalen; - spin_lock(&jffs2_compressor_list_lock); - list_for_each_entry(this, &jffs2_compressor_list, list) { - /* Skip decompress-only backwards-compatibility and disabled modules */ - if ((!this->compress)||(this->disabled)) - continue; + switch (jffs2_compression_mode) { + case JFFS2_COMPR_MODE_NONE: + break; + case JFFS2_COMPR_MODE_PRIORITY: + output_buf = kmalloc(*cdatalen,GFP_KERNEL); + if (!output_buf) { + printk(KERN_WARNING "JFFS2: No memory for compressor allocation. Compression failed.\n"); + goto out; + } + orig_slen = *datalen; + orig_dlen = *cdatalen; + spin_lock(&jffs2_compressor_list_lock); + list_for_each_entry(this, &jffs2_compressor_list, list) { + /* Skip decompress-only backwards-compatibility and disabled modules */ + if ((!this->compress)||(this->disabled)) + continue; - this->usecount++; - spin_unlock(&jffs2_compressor_list_lock); - *datalen = orig_slen; - *cdatalen = orig_dlen; - compr_ret = this->compress(data_in, output_buf, datalen, cdatalen, NULL); - spin_lock(&jffs2_compressor_list_lock); - this->usecount--; - if (!compr_ret) { - ret = this->compr; - this->stat_compr_blocks++; - this->stat_compr_orig_size += *datalen; - this->stat_compr_new_size += *cdatalen; - break; - } - } - spin_unlock(&jffs2_compressor_list_lock); - if (ret == JFFS2_COMPR_NONE) kfree(output_buf); - break; - case JFFS2_COMPR_MODE_SIZE: - orig_slen = *datalen; - orig_dlen = *cdatalen; - spin_lock(&jffs2_compressor_list_lock); - list_for_each_entry(this, &jffs2_compressor_list, list) { - /* 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)&&(this->compr_buf)) { - spin_unlock(&jffs2_compressor_list_lock); - kfree(this->compr_buf); - spin_lock(&jffs2_compressor_list_lock); - this->compr_buf_size=0; - this->compr_buf=NULL; - } - if (!this->compr_buf) { - spin_unlock(&jffs2_compressor_list_lock); - tmp_buf = kmalloc(orig_dlen,GFP_KERNEL); - spin_lock(&jffs2_compressor_list_lock); - if (!tmp_buf) { - printk(KERN_WARNING "JFFS2: No memory for compressor allocation. (%d bytes)\n",orig_dlen); - continue; - } - else { - this->compr_buf = tmp_buf; - this->compr_buf_size = orig_dlen; - } - } - this->usecount++; - spin_unlock(&jffs2_compressor_list_lock); - *datalen = orig_slen; - *cdatalen = orig_dlen; - compr_ret = this->compress(data_in, this->compr_buf, datalen, cdatalen, NULL); - spin_lock(&jffs2_compressor_list_lock); - this->usecount--; - if (!compr_ret) { - if ((!best_dlen)||(best_dlen>*cdatalen)) { - best_dlen = *cdatalen; - best_slen = *datalen; - best = this; - } - } - } - if (best_dlen) { - *cdatalen = best_dlen; - *datalen = best_slen; - output_buf = best->compr_buf; - best->compr_buf = NULL; - best->compr_buf_size = 0; - best->stat_compr_blocks++; - best->stat_compr_orig_size += best_slen; - best->stat_compr_new_size += best_dlen; - ret = best->compr; - } - spin_unlock(&jffs2_compressor_list_lock); - break; - default: - printk(KERN_ERR "JFFS2: unknow compression mode.\n"); - } + this->usecount++; + spin_unlock(&jffs2_compressor_list_lock); + *datalen = orig_slen; + *cdatalen = orig_dlen; + compr_ret = this->compress(data_in, output_buf, datalen, cdatalen, NULL); + spin_lock(&jffs2_compressor_list_lock); + this->usecount--; + if (!compr_ret) { + ret = this->compr; + this->stat_compr_blocks++; + this->stat_compr_orig_size += *datalen; + this->stat_compr_new_size += *cdatalen; + break; + } + } + spin_unlock(&jffs2_compressor_list_lock); + if (ret == JFFS2_COMPR_NONE) + kfree(output_buf); + break; + case JFFS2_COMPR_MODE_SIZE: + case JFFS2_COMPR_MODE_FAVOURLZO: + orig_slen = *datalen; + orig_dlen = *cdatalen; + spin_lock(&jffs2_compressor_list_lock); + list_for_each_entry(this, &jffs2_compressor_list, list) { + /* 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_slen) && (this->compr_buf)) { + spin_unlock(&jffs2_compressor_list_lock); + kfree(this->compr_buf); + spin_lock(&jffs2_compressor_list_lock); + this->compr_buf_size=0; + this->compr_buf=NULL; + } + if (!this->compr_buf) { + spin_unlock(&jffs2_compressor_list_lock); + tmp_buf = kmalloc(orig_slen, GFP_KERNEL); + spin_lock(&jffs2_compressor_list_lock); + if (!tmp_buf) { + printk(KERN_WARNING "JFFS2: No memory for compressor allocation. (%d bytes)\n", orig_slen); + continue; + } + else { + this->compr_buf = tmp_buf; + this->compr_buf_size = orig_slen; + } + } + this->usecount++; + spin_unlock(&jffs2_compressor_list_lock); + *datalen = orig_slen; + *cdatalen = orig_dlen; + compr_ret = this->compress(data_in, this->compr_buf, datalen, cdatalen, NULL); + spin_lock(&jffs2_compressor_list_lock); + this->usecount--; + if (!compr_ret) { + if (((!best_dlen) || jffs2_is_best_compression(this, best, *cdatalen, best_dlen)) + && (*cdatalen < *datalen)) { + best_dlen = *cdatalen; + best_slen = *datalen; + best = this; + } + } + } + if (best_dlen) { + *cdatalen = best_dlen; + *datalen = best_slen; + output_buf = best->compr_buf; + best->compr_buf = NULL; + best->compr_buf_size = 0; + best->stat_compr_blocks++; + best->stat_compr_orig_size += best_slen; + best->stat_compr_new_size += best_dlen; + ret = best->compr; + } + spin_unlock(&jffs2_compressor_list_lock); + break; + default: + printk(KERN_ERR "JFFS2: unknow compression mode.\n"); + } out: - if (ret == JFFS2_COMPR_NONE) { - *cpage_out = data_in; - *datalen = *cdatalen; - none_stat_compr_blocks++; - none_stat_compr_size += *datalen; - } - else { - *cpage_out = output_buf; - } + if (ret == JFFS2_COMPR_NONE) { + *cpage_out = data_in; + *datalen = *cdatalen; + none_stat_compr_blocks++; + none_stat_compr_size += *datalen; + } + else { + *cpage_out = output_buf; + } return ret; } @@ -165,8 +196,8 @@ int jffs2_decompress(struct jffs2_sb_info *c, struct jffs2_inode_info *f, uint16_t comprtype, unsigned char *cdata_in, unsigned char *data_out, uint32_t cdatalen, uint32_t datalen) { - struct jffs2_compressor *this; - int ret; + struct jffs2_compressor *this; + int ret; /* Older code had a bug where it would write non-zero 'usercompr' fields. Deal with it. */ @@ -177,32 +208,32 @@ int jffs2_decompress(struct jffs2_sb_info *c, struct jffs2_inode_info *f, case JFFS2_COMPR_NONE: /* This should be special-cased elsewhere, but we might as well deal with it */ memcpy(data_out, cdata_in, datalen); - none_stat_decompr_blocks++; + none_stat_decompr_blocks++; break; case JFFS2_COMPR_ZERO: memset(data_out, 0, datalen); break; default: - spin_lock(&jffs2_compressor_list_lock); - list_for_each_entry(this, &jffs2_compressor_list, list) { - if (comprtype == this->compr) { - this->usecount++; - spin_unlock(&jffs2_compressor_list_lock); - ret = this->decompress(cdata_in, data_out, cdatalen, datalen, NULL); - spin_lock(&jffs2_compressor_list_lock); - if (ret) { - printk(KERN_WARNING "Decompressor \"%s\" returned %d\n", this->name, ret); - } - else { - this->stat_decompr_blocks++; - } - this->usecount--; - spin_unlock(&jffs2_compressor_list_lock); - return ret; - } - } + spin_lock(&jffs2_compressor_list_lock); + list_for_each_entry(this, &jffs2_compressor_list, list) { + if (comprtype == this->compr) { + this->usecount++; + spin_unlock(&jffs2_compressor_list_lock); + ret = this->decompress(cdata_in, data_out, cdatalen, datalen, NULL); + spin_lock(&jffs2_compressor_list_lock); + if (ret) { + printk(KERN_WARNING "Decompressor \"%s\" returned %d\n", this->name, ret); + } + else { + this->stat_decompr_blocks++; + } + this->usecount--; + spin_unlock(&jffs2_compressor_list_lock); + return ret; + } + } printk(KERN_WARNING "JFFS2 compression type 0x%02x not available.\n", comprtype); - spin_unlock(&jffs2_compressor_list_lock); + spin_unlock(&jffs2_compressor_list_lock); return -EIO; } return 0; @@ -210,108 +241,119 @@ int jffs2_decompress(struct jffs2_sb_info *c, struct jffs2_inode_info *f, int jffs2_register_compressor(struct jffs2_compressor *comp) { - struct jffs2_compressor *this; + struct jffs2_compressor *this; - if (!comp->name) { - printk(KERN_WARNING "NULL compressor name at registering JFFS2 compressor. Failed.\n"); - return -1; - } - comp->compr_buf_size=0; - comp->compr_buf=NULL; - comp->usecount=0; - comp->stat_compr_orig_size=0; - comp->stat_compr_new_size=0; - comp->stat_compr_blocks=0; - comp->stat_decompr_blocks=0; - D1(printk(KERN_DEBUG "Registering JFFS2 compressor \"%s\"\n", comp->name)); + if (!comp->name) { + printk(KERN_WARNING "NULL compressor name at registering JFFS2 compressor. Failed.\n"); + return -1; + } + comp->compr_buf_size=0; + comp->compr_buf=NULL; + comp->usecount=0; + comp->stat_compr_orig_size=0; + comp->stat_compr_new_size=0; + comp->stat_compr_blocks=0; + comp->stat_decompr_blocks=0; + D1(printk(KERN_DEBUG "Registering JFFS2 compressor \"%s\"\n", comp->name)); - spin_lock(&jffs2_compressor_list_lock); + spin_lock(&jffs2_compressor_list_lock); - list_for_each_entry(this, &jffs2_compressor_list, list) { - if (this->priority < comp->priority) { - list_add(&comp->list, this->list.prev); - goto out; - } - } - list_add_tail(&comp->list, &jffs2_compressor_list); + list_for_each_entry(this, &jffs2_compressor_list, list) { + if (this->priority < comp->priority) { + list_add(&comp->list, this->list.prev); + goto out; + } + } + list_add_tail(&comp->list, &jffs2_compressor_list); out: - D2(list_for_each_entry(this, &jffs2_compressor_list, list) { - printk(KERN_DEBUG "Compressor \"%s\", prio %d\n", this->name, this->priority); - }) + D2(list_for_each_entry(this, &jffs2_compressor_list, list) { + printk(KERN_DEBUG "Compressor \"%s\", prio %d\n", this->name, this->priority); + }) - spin_unlock(&jffs2_compressor_list_lock); + spin_unlock(&jffs2_compressor_list_lock); - return 0; + return 0; } int jffs2_unregister_compressor(struct jffs2_compressor *comp) { - D2(struct jffs2_compressor *this;) + D2(struct jffs2_compressor *this;) - D1(printk(KERN_DEBUG "Unregistering JFFS2 compressor \"%s\"\n", comp->name)); + D1(printk(KERN_DEBUG "Unregistering JFFS2 compressor \"%s\"\n", comp->name)); - spin_lock(&jffs2_compressor_list_lock); + spin_lock(&jffs2_compressor_list_lock); - if (comp->usecount) { - spin_unlock(&jffs2_compressor_list_lock); - printk(KERN_WARNING "JFFS2: Compressor modul is in use. Unregister failed.\n"); - return -1; - } - list_del(&comp->list); + if (comp->usecount) { + spin_unlock(&jffs2_compressor_list_lock); + printk(KERN_WARNING "JFFS2: Compressor modul is in use. Unregister failed.\n"); + return -1; + } + list_del(&comp->list); - D2(list_for_each_entry(this, &jffs2_compressor_list, list) { - printk(KERN_DEBUG "Compressor \"%s\", prio %d\n", this->name, this->priority); - }) - spin_unlock(&jffs2_compressor_list_lock); - return 0; + D2(list_for_each_entry(this, &jffs2_compressor_list, list) { + printk(KERN_DEBUG "Compressor \"%s\", prio %d\n", this->name, this->priority); + }) + spin_unlock(&jffs2_compressor_list_lock); + return 0; } void jffs2_free_comprbuf(unsigned char *comprbuf, unsigned char *orig) { - if (orig != comprbuf) - kfree(comprbuf); + if (orig != comprbuf) + kfree(comprbuf); } int __init jffs2_compressors_init(void) { /* Registering compressors */ #ifdef CONFIG_JFFS2_ZLIB - jffs2_zlib_init(); + jffs2_zlib_init(); #endif #ifdef CONFIG_JFFS2_RTIME - jffs2_rtime_init(); + jffs2_rtime_init(); #endif #ifdef CONFIG_JFFS2_RUBIN - jffs2_rubinmips_init(); - jffs2_dynrubin_init(); + jffs2_rubinmips_init(); + jffs2_dynrubin_init(); +#endif +#ifdef CONFIG_JFFS2_LZO + jffs2_lzo_init(); #endif /* Setting default compression mode */ #ifdef CONFIG_JFFS2_CMODE_NONE - jffs2_compression_mode = JFFS2_COMPR_MODE_NONE; - D1(printk(KERN_INFO "JFFS2: default compression mode: none\n");) + jffs2_compression_mode = JFFS2_COMPR_MODE_NONE; + D1(printk(KERN_INFO "JFFS2: default compression mode: none\n");) #else #ifdef CONFIG_JFFS2_CMODE_SIZE - jffs2_compression_mode = JFFS2_COMPR_MODE_SIZE; - D1(printk(KERN_INFO "JFFS2: default compression mode: size\n");) + jffs2_compression_mode = JFFS2_COMPR_MODE_SIZE; + D1(printk(KERN_INFO "JFFS2: default compression mode: size\n");) +#else +#ifdef CONFIG_JFFS2_CMODE_FAVOURLZO + jffs2_compression_mode = JFFS2_COMPR_MODE_FAVOURLZO; + D1(printk(KERN_INFO "JFFS2: default compression mode: favourlzo\n");) #else - D1(printk(KERN_INFO "JFFS2: default compression mode: priority\n");) + D1(printk(KERN_INFO "JFFS2: default compression mode: priority\n");) +#endif #endif #endif - return 0; + return 0; } int jffs2_compressors_exit(void) { /* Unregistering compressors */ +#ifdef CONFIG_JFFS2_LZO + jffs2_lzo_exit(); +#endif #ifdef CONFIG_JFFS2_RUBIN - jffs2_dynrubin_exit(); - jffs2_rubinmips_exit(); + jffs2_dynrubin_exit(); + jffs2_rubinmips_exit(); #endif #ifdef CONFIG_JFFS2_RTIME - jffs2_rtime_exit(); + jffs2_rtime_exit(); #endif #ifdef CONFIG_JFFS2_ZLIB - jffs2_zlib_exit(); + jffs2_zlib_exit(); #endif - return 0; + return 0; } |