| /* |
| * JFFS2 -- Journalling Flash File System, Version 2. |
| * |
| * Copyright (C) 2001-2003 Red Hat, Inc. |
| * Created by Arjan van de Ven <arjanv@redhat.com> |
| * |
| * Copyright (C) 2004 Ferenc Havasi <havasi@inf.u-szeged.hu>, |
| * University of Szeged, Hungary |
| * |
| * For licensing information, see the file 'LICENCE' in this directory. |
| * |
| * $Id: compr.c,v 1.42 2004/08/07 21:56:08 dwmw2 Exp $ |
| * |
| */ |
| |
| #include "compr.h" |
| |
| static DEFINE_SPINLOCK(jffs2_compressor_list_lock); |
| |
| /* Available compressors are on this list */ |
| static LIST_HEAD(jffs2_compressor_list); |
| |
| /* Actual compression mode */ |
| 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; |
| |
| /* jffs2_compress: |
| * @data: Pointer to uncompressed data |
| * @cdata: Pointer to returned pointer to buffer for compressed data |
| * @datalen: On entry, holds the amount of data available for compression. |
| * On exit, expected to hold the amount of data actually compressed. |
| * @cdatalen: On entry, holds the amount of space available for compressed |
| * data. On exit, expected to hold the actual size of the compressed |
| * data. |
| * |
| * Returns: Lower byte to be stored with data indicating compression type used. |
| * Zero is used to show that the data could not be compressed - the |
| * compressed version was actually larger than the original. |
| * Upper byte will be used later. (soon) |
| * |
| * If the cdata buffer isn't large enough to hold all the uncompressed data, |
| * jffs2_compress should compress as much as will fit, and should set |
| * *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) |
| { |
| 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; |
| |
| 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"); |
| } |
| 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; |
| } |
| return ret; |
| } |
| |
| 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; |
| |
| /* Older code had a bug where it would write non-zero 'usercompr' |
| fields. Deal with it. */ |
| if ((comprtype & 0xff) <= JFFS2_COMPR_ZLIB) |
| comprtype &= 0xff; |
| |
| switch (comprtype & 0xff) { |
| 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++; |
| 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; |
| } |
| } |
| printk(KERN_WARNING "JFFS2 compression type 0x%02x not available.\n", comprtype); |
| spin_unlock(&jffs2_compressor_list_lock); |
| return -EIO; |
| } |
| return 0; |
| } |
| |
| int jffs2_register_compressor(struct jffs2_compressor *comp) |
| { |
| 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)); |
| |
| 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); |
| out: |
| 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; |
| } |
| |
| int jffs2_unregister_compressor(struct jffs2_compressor *comp) |
| { |
| D2(struct jffs2_compressor *this;) |
| |
| D1(printk(KERN_DEBUG "Unregistering JFFS2 compressor \"%s\"\n", comp->name)); |
| |
| 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); |
| |
| 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; |
| } |
| |
| #ifdef CONFIG_JFFS2_PROC |
| |
| #define JFFS2_STAT_BUF_SIZE 16000 |
| |
| char *jffs2_list_compressors(void) |
| { |
| struct jffs2_compressor *this; |
| char *buf, *act_buf; |
| |
| act_buf = buf = kmalloc(JFFS2_STAT_BUF_SIZE,GFP_KERNEL); |
| list_for_each_entry(this, &jffs2_compressor_list, list) { |
| act_buf += sprintf(act_buf, "%10s priority:%d ", this->name, this->priority); |
| if ((this->disabled)||(!this->compress)) |
| act_buf += sprintf(act_buf,"disabled"); |
| else |
| act_buf += sprintf(act_buf,"enabled"); |
| act_buf += sprintf(act_buf,"\n"); |
| } |
| return buf; |
| } |
| |
| char *jffs2_stats(void) |
| { |
| struct jffs2_compressor *this; |
| char *buf, *act_buf; |
| |
| act_buf = buf = kmalloc(JFFS2_STAT_BUF_SIZE,GFP_KERNEL); |
| |
| act_buf += sprintf(act_buf,"JFFS2 compressor statistics:\n"); |
| act_buf += sprintf(act_buf,"%10s ","none"); |
| act_buf += sprintf(act_buf,"compr: %d blocks (%d) decompr: %d blocks\n", none_stat_compr_blocks, |
| none_stat_compr_size, none_stat_decompr_blocks); |
| spin_lock(&jffs2_compressor_list_lock); |
| list_for_each_entry(this, &jffs2_compressor_list, list) { |
| act_buf += sprintf(act_buf,"%10s ",this->name); |
| if ((this->disabled)||(!this->compress)) |
| act_buf += sprintf(act_buf,"- "); |
| else |
| act_buf += sprintf(act_buf,"+ "); |
| act_buf += sprintf(act_buf,"compr: %d blocks (%d/%d) decompr: %d blocks ", this->stat_compr_blocks, |
| this->stat_compr_new_size, this->stat_compr_orig_size, |
| this->stat_decompr_blocks); |
| act_buf += sprintf(act_buf,"\n"); |
| } |
| spin_unlock(&jffs2_compressor_list_lock); |
| |
| return buf; |
| } |
| |
| char *jffs2_get_compression_mode_name(void) |
| { |
| switch (jffs2_compression_mode) { |
| case JFFS2_COMPR_MODE_NONE: |
| return "none"; |
| case JFFS2_COMPR_MODE_PRIORITY: |
| return "priority"; |
| case JFFS2_COMPR_MODE_SIZE: |
| return "size"; |
| } |
| return "unkown"; |
| } |
| |
| int jffs2_set_compression_mode_name(const char *name) |
| { |
| if (!strcmp("none",name)) { |
| jffs2_compression_mode = JFFS2_COMPR_MODE_NONE; |
| return 0; |
| } |
| if (!strcmp("priority",name)) { |
| jffs2_compression_mode = JFFS2_COMPR_MODE_PRIORITY; |
| return 0; |
| } |
| if (!strcmp("size",name)) { |
| jffs2_compression_mode = JFFS2_COMPR_MODE_SIZE; |
| return 0; |
| } |
| return 1; |
| } |
| |
| static int jffs2_compressor_Xable(const char *name, int disabled) |
| { |
| struct jffs2_compressor *this; |
| spin_lock(&jffs2_compressor_list_lock); |
| list_for_each_entry(this, &jffs2_compressor_list, list) { |
| if (!strcmp(this->name, name)) { |
| this->disabled = disabled; |
| spin_unlock(&jffs2_compressor_list_lock); |
| return 0; |
| } |
| } |
| spin_unlock(&jffs2_compressor_list_lock); |
| printk(KERN_WARNING "JFFS2: compressor %s not found.\n",name); |
| return 1; |
| } |
| |
| int jffs2_enable_compressor_name(const char *name) |
| { |
| return jffs2_compressor_Xable(name, 0); |
| } |
| |
| int jffs2_disable_compressor_name(const char *name) |
| { |
| return jffs2_compressor_Xable(name, 1); |
| } |
| |
| int jffs2_set_compressor_priority(const char *name, int priority) |
| { |
| struct jffs2_compressor *this,*comp; |
| spin_lock(&jffs2_compressor_list_lock); |
| list_for_each_entry(this, &jffs2_compressor_list, list) { |
| if (!strcmp(this->name, name)) { |
| this->priority = priority; |
| comp = this; |
| goto reinsert; |
| } |
| } |
| spin_unlock(&jffs2_compressor_list_lock); |
| printk(KERN_WARNING "JFFS2: compressor %s not found.\n",name); |
| return 1; |
| reinsert: |
| /* list is sorted in the order of priority, so if |
| we change it we have to reinsert it into the |
| good place */ |
| list_del(&comp->list); |
| list_for_each_entry(this, &jffs2_compressor_list, list) { |
| if (this->priority < comp->priority) { |
| list_add(&comp->list, this->list.prev); |
| spin_unlock(&jffs2_compressor_list_lock); |
| return 0; |
| } |
| } |
| list_add_tail(&comp->list, &jffs2_compressor_list); |
| spin_unlock(&jffs2_compressor_list_lock); |
| return 0; |
| } |
| |
| #endif |
| |
| void jffs2_free_comprbuf(unsigned char *comprbuf, unsigned char *orig) |
| { |
| if (orig != comprbuf) |
| kfree(comprbuf); |
| } |
| |
| int jffs2_compressors_init(void) |
| { |
| /* Registering compressors */ |
| #ifdef CONFIG_JFFS2_ZLIB |
| jffs2_zlib_init(); |
| #endif |
| #ifdef CONFIG_JFFS2_RTIME |
| jffs2_rtime_init(); |
| #endif |
| #ifdef CONFIG_JFFS2_RUBIN |
| jffs2_rubinmips_init(); |
| jffs2_dynrubin_init(); |
| #endif |
| #ifdef CONFIG_JFFS2_LZARI |
| jffs2_lzari_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");) |
| #else |
| #ifdef CONFIG_JFFS2_CMODE_SIZE |
| jffs2_compression_mode = JFFS2_COMPR_MODE_SIZE; |
| D1(printk(KERN_INFO "JFFS2: default compression mode: size\n");) |
| #else |
| D1(printk(KERN_INFO "JFFS2: default compression mode: priority\n");) |
| #endif |
| #endif |
| return 0; |
| } |
| |
| int jffs2_compressors_exit(void) |
| { |
| /* Unregistering compressors */ |
| #ifdef CONFIG_JFFS2_LZO |
| jffs2_lzo_exit(); |
| #endif |
| #ifdef CONFIG_JFFS2_LZARI |
| jffs2_lzari_exit(); |
| #endif |
| #ifdef CONFIG_JFFS2_RUBIN |
| jffs2_dynrubin_exit(); |
| jffs2_rubinmips_exit(); |
| #endif |
| #ifdef CONFIG_JFFS2_RTIME |
| jffs2_rtime_exit(); |
| #endif |
| #ifdef CONFIG_JFFS2_ZLIB |
| jffs2_zlib_exit(); |
| #endif |
| return 0; |
| } |
