fs/jffs2/compr_rubin.c - kernel/msm-4.9 - Gitiles

 /*
  * JFFS2 -- Journalling Flash File System, Version 2.
  *
  * Copyright © 2001-2007 Red Hat, Inc.
  * Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
  *
  * Created by Arjan van de Ven <arjanv@redhat.com>
  *
  * For licensing information, see the file 'LICENCE' in this directory.
  *
  */

 #define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

 #include <linux/string.h>
 #include <linux/types.h>
 #include <linux/jffs2.h>
 #include <linux/errno.h>
 #include "compr.h"


 #define RUBIN_REG_SIZE   16
 #define UPPER_BIT_RUBIN    (((long) 1)<<(RUBIN_REG_SIZE-1))
 #define LOWER_BITS_RUBIN   ((((long) 1)<<(RUBIN_REG_SIZE-1))-1)


 #define BIT_DIVIDER_MIPS 1043
 static int bits_mips[8] = { 277, 249, 290, 267, 229, 341, 212, 241};

 struct pushpull {
 	unsigned char *buf;
 	unsigned int buflen;
 	unsigned int ofs;
 	unsigned int reserve;
 };

 struct rubin_state {
 	unsigned long p;
 	unsigned long q;
 	unsigned long rec_q;
 	long bit_number;
 	struct pushpull pp;
 	int bit_divider;
 	int bits[8];
 };

 static inline void init_pushpull(struct pushpull *pp, char *buf,
 				 unsigned buflen, unsigned ofs,
 				 unsigned reserve)
 {
 	pp->buf = buf;
 	pp->buflen = buflen;
 	pp->ofs = ofs;
 	pp->reserve = reserve;
 }

 static inline int pushbit(struct pushpull *pp, int bit, int use_reserved)
 {
 	if (pp->ofs >= pp->buflen - (use_reserved?0:pp->reserve))
 		return -ENOSPC;

 	if (bit)
 		pp->buf[pp->ofs >> 3] |= (1<<(7-(pp->ofs & 7)));
 	else
 		pp->buf[pp->ofs >> 3] &= ~(1<<(7-(pp->ofs & 7)));

 	pp->ofs++;

 	return 0;
 }

 static inline int pushedbits(struct pushpull *pp)
 {
 	return pp->ofs;
 }

 static inline int pullbit(struct pushpull *pp)
 {
 	int bit;

 	bit = (pp->buf[pp->ofs >> 3] >> (7-(pp->ofs & 7))) & 1;

 	pp->ofs++;
 	return bit;
 }

 static inline int pulledbits(struct pushpull *pp)
 {
 	return pp->ofs;
 }


 static void init_rubin(struct rubin_state *rs, int div, int *bits)
 {
 	int c;

 	rs->q = 0;
 	rs->p = (long) (2 * UPPER_BIT_RUBIN);
 	rs->bit_number = (long) 0;
 	rs->bit_divider = div;

 	for (c=0; c<8; c++)
 		rs->bits[c] = bits[c];
 }


 static int encode(struct rubin_state *rs, long A, long B, int symbol)
 {

 	long i0, i1;
 	int ret;

 	while ((rs->q >= UPPER_BIT_RUBIN) ||
 	       ((rs->p + rs->q) <= UPPER_BIT_RUBIN)) {
 		rs->bit_number++;

 		ret = pushbit(&rs->pp, (rs->q & UPPER_BIT_RUBIN) ? 1 : 0, 0);
 		if (ret)
 			return ret;
 		rs->q &= LOWER_BITS_RUBIN;
 		rs->q <<= 1;
 		rs->p <<= 1;
 	}
 	i0 = A * rs->p / (A + B);
 	if (i0 <= 0)
 		i0 = 1;

 	if (i0 >= rs->p)
 		i0 = rs->p - 1;

 	i1 = rs->p - i0;

 	if (symbol == 0)
 		rs->p = i0;
 	else {
 		rs->p = i1;
 		rs->q += i0;
 	}
 	return 0;
 }


 static void end_rubin(struct rubin_state *rs)
 {

 	int i;

 	for (i = 0; i < RUBIN_REG_SIZE; i++) {
 		pushbit(&rs->pp, (UPPER_BIT_RUBIN & rs->q) ? 1 : 0, 1);
 		rs->q &= LOWER_BITS_RUBIN;
 		rs->q <<= 1;
 	}
 }


 static void init_decode(struct rubin_state *rs, int div, int *bits)
 {
 	init_rubin(rs, div, bits);

 	/* behalve lower */
 	rs->rec_q = 0;

 	for (rs->bit_number = 0; rs->bit_number++ < RUBIN_REG_SIZE;
 	     rs->rec_q = rs->rec_q * 2 + (long) (pullbit(&rs->pp)))
 		;
 }

 static void __do_decode(struct rubin_state *rs, unsigned long p,
 			unsigned long q)
 {
 	register unsigned long lower_bits_rubin = LOWER_BITS_RUBIN;
 	unsigned long rec_q;
 	int c, bits = 0;

 	/*
 	 * First, work out how many bits we need from the input stream.
 	 * Note that we have already done the initial check on this
 	 * loop prior to calling this function.
 	 */
 	do {
 		bits++;
 		q &= lower_bits_rubin;
 		q <<= 1;
 		p <<= 1;
 	} while ((q >= UPPER_BIT_RUBIN) || ((p + q) <= UPPER_BIT_RUBIN));

 	rs->p = p;
 	rs->q = q;

 	rs->bit_number += bits;

 	/*
 	 * Now get the bits.  We really want this to be "get n bits".
 	 */
 	rec_q = rs->rec_q;
 	do {
 		c = pullbit(&rs->pp);
 		rec_q &= lower_bits_rubin;
 		rec_q <<= 1;
 		rec_q += c;
 	} while (--bits);
 	rs->rec_q = rec_q;
 }

 static int decode(struct rubin_state *rs, long A, long B)
 {
 	unsigned long p = rs->p, q = rs->q;
 	long i0, threshold;
 	int symbol;

 	if (q >= UPPER_BIT_RUBIN || ((p + q) <= UPPER_BIT_RUBIN))
 		__do_decode(rs, p, q);

 	i0 = A * rs->p / (A + B);
 	if (i0 <= 0)
 		i0 = 1;

 	if (i0 >= rs->p)
 		i0 = rs->p - 1;

 	threshold = rs->q + i0;
 	symbol = rs->rec_q >= threshold;
 	if (rs->rec_q >= threshold) {
 		rs->q += i0;
 		i0 = rs->p - i0;
 	}

 	rs->p = i0;

 	return symbol;
 }


 static int out_byte(struct rubin_state *rs, unsigned char byte)
 {
 	int i, ret;
 	struct rubin_state rs_copy;
 	rs_copy = *rs;

 	for (i=0; i<8; i++) {
 		ret = encode(rs, rs->bit_divider-rs->bits[i],
 			     rs->bits[i], byte & 1);
 		if (ret) {
 			/* Failed. Restore old state */
 			*rs = rs_copy;
 			return ret;
 		}
 		byte >>= 1 ;
 	}
 	return 0;
 }

 static int in_byte(struct rubin_state *rs)
 {
 	int i, result = 0, bit_divider = rs->bit_divider;

 	for (i = 0; i < 8; i++)
 		result |= decode(rs, bit_divider - rs->bits[i],
 				 rs->bits[i]) << i;

 	return result;
 }


 static int rubin_do_compress(int bit_divider, int *bits, unsigned char *data_in,
 			     unsigned char *cpage_out, uint32_t *sourcelen,
 			     uint32_t *dstlen)
 	{
 	int outpos = 0;
 	int pos=0;
 	struct rubin_state rs;

 	init_pushpull(&rs.pp, cpage_out, *dstlen * 8, 0, 32);

 	init_rubin(&rs, bit_divider, bits);

 	while (pos < (*sourcelen) && !out_byte(&rs, data_in[pos]))
 		pos++;

 	end_rubin(&rs);

 	if (outpos > pos) {
 		/* We failed */
 		return -1;
 	}

 	/* Tell the caller how much we managed to compress,
 	 * and how much space it took */

 	outpos = (pushedbits(&rs.pp)+7)/8;

 	if (outpos >= pos)
 		return -1; /* We didn't actually compress */
 	*sourcelen = pos;
 	*dstlen = outpos;
 	return 0;
 }
 #if 0
 /* _compress returns the compressed size, -1 if bigger */
 int jffs2_rubinmips_compress(unsigned char *data_in, unsigned char *cpage_out,
 		   uint32_t *sourcelen, uint32_t *dstlen)
 {
 	return rubin_do_compress(BIT_DIVIDER_MIPS, bits_mips, data_in,
 				 cpage_out, sourcelen, dstlen);
 }
 #endif
 static int jffs2_dynrubin_compress(unsigned char *data_in,
 				   unsigned char *cpage_out,
 				   uint32_t *sourcelen, uint32_t *dstlen)
 {
 	int bits[8];
 	unsigned char histo[256];
 	int i;
 	int ret;
 	uint32_t mysrclen, mydstlen;

 	mysrclen = *sourcelen;
 	mydstlen = *dstlen - 8;

 	if (*dstlen <= 12)
 		return -1;

 	memset(histo, 0, 256);
 	for (i=0; i<mysrclen; i++)
 		histo[data_in[i]]++;
 	memset(bits, 0, sizeof(int)*8);
 	for (i=0; i<256; i++) {
 		if (i&128)
 			bits[7] += histo[i];
 		if (i&64)
 			bits[6] += histo[i];
 		if (i&32)
 			bits[5] += histo[i];
 		if (i&16)
 			bits[4] += histo[i];
 		if (i&8)
 			bits[3] += histo[i];
 		if (i&4)
 			bits[2] += histo[i];
 		if (i&2)
 			bits[1] += histo[i];
 		if (i&1)
 			bits[0] += histo[i];
 	}

 	for (i=0; i<8; i++) {
 		bits[i] = (bits[i] * 256) / mysrclen;
 		if (!bits[i]) bits[i] = 1;
 		if (bits[i] > 255) bits[i] = 255;
 		cpage_out[i] = bits[i];
 	}

 	ret = rubin_do_compress(256, bits, data_in, cpage_out+8, &mysrclen,
 				&mydstlen);
 	if (ret)
 		return ret;

 	/* Add back the 8 bytes we took for the probabilities */
 	mydstlen += 8;

 	if (mysrclen <= mydstlen) {
 		/* We compressed */
 		return -1;
 	}

 	*sourcelen = mysrclen;
 	*dstlen = mydstlen;
 	return 0;
 }

 static void rubin_do_decompress(int bit_divider, int *bits,
 				unsigned char *cdata_in,
 				unsigned char *page_out, uint32_t srclen,
 				uint32_t destlen)
 {
 	int outpos = 0;
 	struct rubin_state rs;

 	init_pushpull(&rs.pp, cdata_in, srclen, 0, 0);
 	init_decode(&rs, bit_divider, bits);

 	while (outpos < destlen)
 		page_out[outpos++] = in_byte(&rs);
 }


 static int jffs2_rubinmips_decompress(unsigned char *data_in,
 				      unsigned char *cpage_out,
 				      uint32_t sourcelen, uint32_t dstlen)
 {
 	rubin_do_decompress(BIT_DIVIDER_MIPS, bits_mips, data_in,
 			    cpage_out, sourcelen, dstlen);
 	return 0;
 }

 static int jffs2_dynrubin_decompress(unsigned char *data_in,
 				     unsigned char *cpage_out,
 				     uint32_t sourcelen, uint32_t dstlen)
 {
 	int bits[8];
 	int c;

 	for (c=0; c<8; c++)
 		bits[c] = data_in[c];

 	rubin_do_decompress(256, bits, data_in+8, cpage_out, sourcelen-8,
 			    dstlen);
 	return 0;
 }

 static struct jffs2_compressor jffs2_rubinmips_comp = {
 	.priority = JFFS2_RUBINMIPS_PRIORITY,
 	.name = "rubinmips",
 	.compr = JFFS2_COMPR_DYNRUBIN,
 	.compress = NULL, /*&jffs2_rubinmips_compress,*/
 	.decompress = &jffs2_rubinmips_decompress,
 #ifdef JFFS2_RUBINMIPS_DISABLED
 	.disabled = 1,
 #else
 	.disabled = 0,
 #endif
 };

 int jffs2_rubinmips_init(void)
 {
 	return jffs2_register_compressor(&jffs2_rubinmips_comp);
 }

 void jffs2_rubinmips_exit(void)
 {
 	jffs2_unregister_compressor(&jffs2_rubinmips_comp);
 }

 static struct jffs2_compressor jffs2_dynrubin_comp = {
 	.priority = JFFS2_DYNRUBIN_PRIORITY,
 	.name = "dynrubin",
 	.compr = JFFS2_COMPR_RUBINMIPS,
 	.compress = jffs2_dynrubin_compress,
 	.decompress = &jffs2_dynrubin_decompress,
 #ifdef JFFS2_DYNRUBIN_DISABLED
 	.disabled = 1,
 #else
 	.disabled = 0,
 #endif
 };

 int jffs2_dynrubin_init(void)
 {
 	return jffs2_register_compressor(&jffs2_dynrubin_comp);
 }

 void jffs2_dynrubin_exit(void)
 {
 	jffs2_unregister_compressor(&jffs2_dynrubin_comp);
 }
	/*
	* JFFS2 -- Journalling Flash File System, Version 2.
	*
	* Copyright © 2001-2007 Red Hat, Inc.
	* Copyright © 2004-2010 David Woodhouse <dwmw2@infradead.org>
	*
	* Created by Arjan van de Ven <arjanv@redhat.com>
	*
	* For licensing information, see the file 'LICENCE' in this directory.
	*
	*/

	#define pr_fmt(fmt) KBUILD_MODNAME ": " fmt

	#include <linux/string.h>
	#include <linux/types.h>
	#include <linux/jffs2.h>
	#include <linux/errno.h>
	#include "compr.h"


	#define RUBIN_REG_SIZE 16
	#define UPPER_BIT_RUBIN (((long) 1)<<(RUBIN_REG_SIZE-1))
	#define LOWER_BITS_RUBIN ((((long) 1)<<(RUBIN_REG_SIZE-1))-1)


	#define BIT_DIVIDER_MIPS 1043
	static int bits_mips[8] = { 277, 249, 290, 267, 229, 341, 212, 241};

	struct pushpull {
	unsigned char *buf;
	unsigned int buflen;
	unsigned int ofs;
	unsigned int reserve;
	};

	struct rubin_state {
	unsigned long p;
	unsigned long q;
	unsigned long rec_q;
	long bit_number;
	struct pushpull pp;
	int bit_divider;
	int bits[8];
	};

	static inline void init_pushpull(struct pushpull pp, char buf,
	unsigned buflen, unsigned ofs,
	unsigned reserve)
	{
	pp->buf = buf;
	pp->buflen = buflen;
	pp->ofs = ofs;
	pp->reserve = reserve;
	}

	static inline int pushbit(struct pushpull *pp, int bit, int use_reserved)
	{
	if (pp->ofs >= pp->buflen - (use_reserved?0:pp->reserve))
	return -ENOSPC;

	if (bit)
	pp->buf[pp->ofs >> 3] \|= (1<<(7-(pp->ofs & 7)));
	else
	pp->buf[pp->ofs >> 3] &= ~(1<<(7-(pp->ofs & 7)));

	pp->ofs++;

	return 0;
	}

	static inline int pushedbits(struct pushpull *pp)
	{
	return pp->ofs;
	}

	static inline int pullbit(struct pushpull *pp)
	{
	int bit;

	bit = (pp->buf[pp->ofs >> 3] >> (7-(pp->ofs & 7))) & 1;

	pp->ofs++;
	return bit;
	}

	static inline int pulledbits(struct pushpull *pp)
	{
	return pp->ofs;
	}


	static void init_rubin(struct rubin_state rs, int div, int bits)
	{
	int c;

	rs->q = 0;
	rs->p = (long) (2 * UPPER_BIT_RUBIN);
	rs->bit_number = (long) 0;
	rs->bit_divider = div;

	for (c=0; c<8; c++)
	rs->bits[c] = bits[c];
	}


	static int encode(struct rubin_state *rs, long A, long B, int symbol)
	{

	long i0, i1;
	int ret;

	while ((rs->q >= UPPER_BIT_RUBIN) \|\|
	((rs->p + rs->q) <= UPPER_BIT_RUBIN)) {
	rs->bit_number++;

	ret = pushbit(&rs->pp, (rs->q & UPPER_BIT_RUBIN) ? 1 : 0, 0);
	if (ret)
	return ret;
	rs->q &= LOWER_BITS_RUBIN;
	rs->q <<= 1;
	rs->p <<= 1;
	}
	i0 = A * rs->p / (A + B);
	if (i0 <= 0)
	i0 = 1;

	if (i0 >= rs->p)
	i0 = rs->p - 1;

	i1 = rs->p - i0;

	if (symbol == 0)
	rs->p = i0;
	else {
	rs->p = i1;
	rs->q += i0;
	}
	return 0;
	}


	static void end_rubin(struct rubin_state *rs)
	{

	int i;

	for (i = 0; i < RUBIN_REG_SIZE; i++) {
	pushbit(&rs->pp, (UPPER_BIT_RUBIN & rs->q) ? 1 : 0, 1);
	rs->q &= LOWER_BITS_RUBIN;
	rs->q <<= 1;
	}
	}


	static void init_decode(struct rubin_state rs, int div, int bits)
	{
	init_rubin(rs, div, bits);

	/* behalve lower */
	rs->rec_q = 0;

	for (rs->bit_number = 0; rs->bit_number++ < RUBIN_REG_SIZE;
	rs->rec_q = rs->rec_q * 2 + (long) (pullbit(&rs->pp)))
	;
	}

	static void __do_decode(struct rubin_state *rs, unsigned long p,
	unsigned long q)
	{
	register unsigned long lower_bits_rubin = LOWER_BITS_RUBIN;
	unsigned long rec_q;
	int c, bits = 0;

	/*
	* First, work out how many bits we need from the input stream.
	* Note that we have already done the initial check on this
	* loop prior to calling this function.
	*/
	do {
	bits++;
	q &= lower_bits_rubin;
	q <<= 1;
	p <<= 1;
	} while ((q >= UPPER_BIT_RUBIN) \|\| ((p + q) <= UPPER_BIT_RUBIN));

	rs->p = p;
	rs->q = q;

	rs->bit_number += bits;

	/*
	* Now get the bits. We really want this to be "get n bits".
	*/
	rec_q = rs->rec_q;
	do {
	c = pullbit(&rs->pp);
	rec_q &= lower_bits_rubin;
	rec_q <<= 1;
	rec_q += c;
	} while (--bits);
	rs->rec_q = rec_q;
	}

	static int decode(struct rubin_state *rs, long A, long B)
	{
	unsigned long p = rs->p, q = rs->q;
	long i0, threshold;
	int symbol;

	if (q >= UPPER_BIT_RUBIN \|\| ((p + q) <= UPPER_BIT_RUBIN))
	__do_decode(rs, p, q);

	i0 = A * rs->p / (A + B);
	if (i0 <= 0)
	i0 = 1;

	if (i0 >= rs->p)
	i0 = rs->p - 1;

	threshold = rs->q + i0;
	symbol = rs->rec_q >= threshold;
	if (rs->rec_q >= threshold) {
	rs->q += i0;
	i0 = rs->p - i0;
	}

	rs->p = i0;

	return symbol;
	}



	static int out_byte(struct rubin_state *rs, unsigned char byte)
	{
	int i, ret;
	struct rubin_state rs_copy;
	rs_copy = *rs;

	for (i=0; i<8; i++) {
	ret = encode(rs, rs->bit_divider-rs->bits[i],
	rs->bits[i], byte & 1);
	if (ret) {
	/* Failed. Restore old state */
	*rs = rs_copy;
	return ret;
	}
	byte >>= 1 ;
	}
	return 0;
	}

	static int in_byte(struct rubin_state *rs)
	{
	int i, result = 0, bit_divider = rs->bit_divider;

	for (i = 0; i < 8; i++)
	result \|= decode(rs, bit_divider - rs->bits[i],
	rs->bits[i]) << i;

	return result;
	}



	static int rubin_do_compress(int bit_divider, int bits, unsigned char data_in,
	unsigned char cpage_out, uint32_t sourcelen,
	uint32_t *dstlen)
	{
	int outpos = 0;
	int pos=0;
	struct rubin_state rs;

	init_pushpull(&rs.pp, cpage_out, dstlen 8, 0, 32);

	init_rubin(&rs, bit_divider, bits);

	while (pos < (*sourcelen) && !out_byte(&rs, data_in[pos]))
	pos++;

	end_rubin(&rs);

	if (outpos > pos) {
	/* We failed */
	return -1;
	}

	/* Tell the caller how much we managed to compress,
	* and how much space it took */

	outpos = (pushedbits(&rs.pp)+7)/8;

	if (outpos >= pos)
	return -1; /* We didn't actually compress */
	*sourcelen = pos;
	*dstlen = outpos;
	return 0;
	}
	#if 0
	/* _compress returns the compressed size, -1 if bigger */
	int jffs2_rubinmips_compress(unsigned char data_in, unsigned char cpage_out,
	uint32_t sourcelen, uint32_t dstlen)
	{
	return rubin_do_compress(BIT_DIVIDER_MIPS, bits_mips, data_in,
	cpage_out, sourcelen, dstlen);
	}
	#endif
	static int jffs2_dynrubin_compress(unsigned char *data_in,
	unsigned char *cpage_out,
	uint32_t sourcelen, uint32_t dstlen)
	{
	int bits[8];
	unsigned char histo[256];
	int i;
	int ret;
	uint32_t mysrclen, mydstlen;

	mysrclen = *sourcelen;
	mydstlen = *dstlen - 8;

	if (*dstlen <= 12)
	return -1;

	memset(histo, 0, 256);
	for (i=0; i<mysrclen; i++)
	histo[data_in[i]]++;
	memset(bits, 0, sizeof(int)*8);
	for (i=0; i<256; i++) {
	if (i&128)
	bits[7] += histo[i];
	if (i&64)
	bits[6] += histo[i];
	if (i&32)
	bits[5] += histo[i];
	if (i&16)
	bits[4] += histo[i];
	if (i&8)
	bits[3] += histo[i];
	if (i&4)
	bits[2] += histo[i];
	if (i&2)
	bits[1] += histo[i];
	if (i&1)
	bits[0] += histo[i];
	}

	for (i=0; i<8; i++) {
	bits[i] = (bits[i] * 256) / mysrclen;
	if (!bits[i]) bits[i] = 1;
	if (bits[i] > 255) bits[i] = 255;
	cpage_out[i] = bits[i];
	}

	ret = rubin_do_compress(256, bits, data_in, cpage_out+8, &mysrclen,
	&mydstlen);
	if (ret)
	return ret;

	/* Add back the 8 bytes we took for the probabilities */
	mydstlen += 8;

	if (mysrclen <= mydstlen) {
	/* We compressed */
	return -1;
	}

	*sourcelen = mysrclen;
	*dstlen = mydstlen;
	return 0;
	}

	static void rubin_do_decompress(int bit_divider, int *bits,
	unsigned char *cdata_in,
	unsigned char *page_out, uint32_t srclen,
	uint32_t destlen)
	{
	int outpos = 0;
	struct rubin_state rs;

	init_pushpull(&rs.pp, cdata_in, srclen, 0, 0);
	init_decode(&rs, bit_divider, bits);

	while (outpos < destlen)
	page_out[outpos++] = in_byte(&rs);
	}


	static int jffs2_rubinmips_decompress(unsigned char *data_in,
	unsigned char *cpage_out,
	uint32_t sourcelen, uint32_t dstlen)
	{
	rubin_do_decompress(BIT_DIVIDER_MIPS, bits_mips, data_in,
	cpage_out, sourcelen, dstlen);
	return 0;
	}

	static int jffs2_dynrubin_decompress(unsigned char *data_in,
	unsigned char *cpage_out,
	uint32_t sourcelen, uint32_t dstlen)
	{
	int bits[8];
	int c;

	for (c=0; c<8; c++)
	bits[c] = data_in[c];

	rubin_do_decompress(256, bits, data_in+8, cpage_out, sourcelen-8,
	dstlen);
	return 0;
	}

	static struct jffs2_compressor jffs2_rubinmips_comp = {
	.priority = JFFS2_RUBINMIPS_PRIORITY,
	.name = "rubinmips",
	.compr = JFFS2_COMPR_DYNRUBIN,
	.compress = NULL, /&jffs2_rubinmips_compress,/
	.decompress = &jffs2_rubinmips_decompress,
	#ifdef JFFS2_RUBINMIPS_DISABLED
	.disabled = 1,
	#else
	.disabled = 0,
	#endif
	};

	int jffs2_rubinmips_init(void)
	{
	return jffs2_register_compressor(&jffs2_rubinmips_comp);
	}

	void jffs2_rubinmips_exit(void)
	{
	jffs2_unregister_compressor(&jffs2_rubinmips_comp);
	}

	static struct jffs2_compressor jffs2_dynrubin_comp = {
	.priority = JFFS2_DYNRUBIN_PRIORITY,
	.name = "dynrubin",
	.compr = JFFS2_COMPR_RUBINMIPS,
	.compress = jffs2_dynrubin_compress,
	.decompress = &jffs2_dynrubin_decompress,
	#ifdef JFFS2_DYNRUBIN_DISABLED
	.disabled = 1,
	#else
	.disabled = 0,
	#endif
	};

	int jffs2_dynrubin_init(void)
	{
	return jffs2_register_compressor(&jffs2_dynrubin_comp);
	}

	void jffs2_dynrubin_exit(void)
	{
	jffs2_unregister_compressor(&jffs2_dynrubin_comp);
	}