458 lines
17 KiB
C
458 lines
17 KiB
C
/*
|
|
* 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 1.46 2005/11/07 11:14:38 gleixner 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
|
|
/* 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_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;
|
|
}
|