[thirdparty/linux.git] / lib / lzo / lzo1x_compress.c

// SPDX-License-Identifier: GPL-2.0-only
/*
 *  LZO1X Compressor from LZO
 *
 *  Copyright (C) 1996-2012 Markus F.X.J. Oberhumer <markus@oberhumer.com>
 *
 *  The full LZO package can be found at:
 *  http://www.oberhumer.com/opensource/lzo/
 *
 *  Changed for Linux kernel use by:
 *  Nitin Gupta <nitingupta910@gmail.com>
 *  Richard Purdie <rpurdie@openedhand.com>
 */

#include <linux/module.h>
#include <linux/kernel.h>
#include <asm/unaligned.h>
#include <linux/lzo.h>
#include "lzodefs.h"

static noinline size_t
lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
		    unsigned char *out, size_t *out_len,
		    size_t ti, void *wrkmem, signed char *state_offset,
		    const unsigned char bitstream_version)
{
	const unsigned char *ip;
	unsigned char *op;
	const unsigned char * const in_end = in + in_len;
	const unsigned char * const ip_end = in + in_len - 20;
	const unsigned char *ii;
	lzo_dict_t * const dict = (lzo_dict_t *) wrkmem;

	op = out;
	ip = in;
	ii = ip;
	ip += ti < 4 ? 4 - ti : 0;

	for (;;) {
		const unsigned char *m_pos = NULL;
		size_t t, m_len, m_off;
		u32 dv;
		u32 run_length = 0;
literal:
		ip += 1 + ((ip - ii) >> 5);
next:
		if (unlikely(ip >= ip_end))
			break;
		dv = get_unaligned_le32(ip);

		if (dv == 0 && bitstream_version) {
			const unsigned char *ir = ip + 4;
			const unsigned char *limit = ip_end
				< (ip + MAX_ZERO_RUN_LENGTH + 1)
				? ip_end : ip + MAX_ZERO_RUN_LENGTH + 1;
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && \
	defined(LZO_FAST_64BIT_MEMORY_ACCESS)
			u64 dv64;

			for (; (ir + 32) <= limit; ir += 32) {
				dv64 = get_unaligned((u64 *)ir);
				dv64 |= get_unaligned((u64 *)ir + 1);
				dv64 |= get_unaligned((u64 *)ir + 2);
				dv64 |= get_unaligned((u64 *)ir + 3);
				if (dv64)
					break;
			}
			for (; (ir + 8) <= limit; ir += 8) {
				dv64 = get_unaligned((u64 *)ir);
				if (dv64) {
#  if defined(__LITTLE_ENDIAN)
					ir += __builtin_ctzll(dv64) >> 3;
#  elif defined(__BIG_ENDIAN)
					ir += __builtin_clzll(dv64) >> 3;
#  else
#    error "missing endian definition"
#  endif
					break;
				}
			}
#else
			while ((ir < (const unsigned char *)
					ALIGN((uintptr_t)ir, 4)) &&
					(ir < limit) && (*ir == 0))
				ir++;
			if (IS_ALIGNED((uintptr_t)ir, 4)) {
				for (; (ir + 4) <= limit; ir += 4) {
					dv = *((u32 *)ir);
					if (dv) {
#  if defined(__LITTLE_ENDIAN)
						ir += __builtin_ctz(dv) >> 3;
#  elif defined(__BIG_ENDIAN)
						ir += __builtin_clz(dv) >> 3;
#  else
#    error "missing endian definition"
#  endif
						break;
					}
				}
			}
#endif
			while (likely(ir < limit) && unlikely(*ir == 0))
				ir++;
			run_length = ir - ip;
			if (run_length > MAX_ZERO_RUN_LENGTH)
				run_length = MAX_ZERO_RUN_LENGTH;
		} else {
			t = ((dv * 0x1824429d) >> (32 - D_BITS)) & D_MASK;
			m_pos = in + dict[t];
			dict[t] = (lzo_dict_t) (ip - in);
			if (unlikely(dv != get_unaligned_le32(m_pos)))
				goto literal;
		}

		ii -= ti;
		ti = 0;
		t = ip - ii;
		if (t != 0) {
			if (t <= 3) {
				op[*state_offset] |= t;
				COPY4(op, ii);
				op += t;
			} else if (t <= 16) {
				*op++ = (t - 3);
				COPY8(op, ii);
				COPY8(op + 8, ii + 8);
				op += t;
			} else {
				if (t <= 18) {
					*op++ = (t - 3);
				} else {
					size_t tt = t - 18;
					*op++ = 0;
					while (unlikely(tt > 255)) {
						tt -= 255;
						*op++ = 0;
					}
					*op++ = tt;
				}
				do {
					COPY8(op, ii);
					COPY8(op + 8, ii + 8);
					op += 16;
					ii += 16;
					t -= 16;
				} while (t >= 16);
				if (t > 0) do {
					*op++ = *ii++;
				} while (--t > 0);
			}
		}

		if (unlikely(run_length)) {
			ip += run_length;
			run_length -= MIN_ZERO_RUN_LENGTH;
			put_unaligned_le32((run_length << 21) | 0xfffc18
					   | (run_length & 0x7), op);
			op += 4;
			run_length = 0;
			*state_offset = -3;
			goto finished_writing_instruction;
		}

		m_len = 4;
		{
#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && defined(LZO_USE_CTZ64)
		u64 v;
		v = get_unaligned((const u64 *) (ip + m_len)) ^
		    get_unaligned((const u64 *) (m_pos + m_len));
		if (unlikely(v == 0)) {
			do {
				m_len += 8;
				v = get_unaligned((const u64 *) (ip + m_len)) ^
				    get_unaligned((const u64 *) (m_pos + m_len));
				if (unlikely(ip + m_len >= ip_end))
					goto m_len_done;
			} while (v == 0);
		}
#  if defined(__LITTLE_ENDIAN)
		m_len += (unsigned) __builtin_ctzll(v) / 8;
#  elif defined(__BIG_ENDIAN)
		m_len += (unsigned) __builtin_clzll(v) / 8;
#  else
#    error "missing endian definition"
#  endif
#elif defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && defined(LZO_USE_CTZ32)
		u32 v;
		v = get_unaligned((const u32 *) (ip + m_len)) ^
		    get_unaligned((const u32 *) (m_pos + m_len));
		if (unlikely(v == 0)) {
			do {
				m_len += 4;
				v = get_unaligned((const u32 *) (ip + m_len)) ^
				    get_unaligned((const u32 *) (m_pos + m_len));
				if (v != 0)
					break;
				m_len += 4;
				v = get_unaligned((const u32 *) (ip + m_len)) ^
				    get_unaligned((const u32 *) (m_pos + m_len));
				if (unlikely(ip + m_len >= ip_end))
					goto m_len_done;
			} while (v == 0);
		}
#  if defined(__LITTLE_ENDIAN)
		m_len += (unsigned) __builtin_ctz(v) / 8;
#  elif defined(__BIG_ENDIAN)
		m_len += (unsigned) __builtin_clz(v) / 8;
#  else
#    error "missing endian definition"
#  endif
#else
		if (unlikely(ip[m_len] == m_pos[m_len])) {
			do {
				m_len += 1;
				if (ip[m_len] != m_pos[m_len])
					break;
				m_len += 1;
				if (ip[m_len] != m_pos[m_len])
					break;
				m_len += 1;
				if (ip[m_len] != m_pos[m_len])
					break;
				m_len += 1;
				if (ip[m_len] != m_pos[m_len])
					break;
				m_len += 1;
				if (ip[m_len] != m_pos[m_len])
					break;
				m_len += 1;
				if (ip[m_len] != m_pos[m_len])
					break;
				m_len += 1;
				if (ip[m_len] != m_pos[m_len])
					break;
				m_len += 1;
				if (unlikely(ip + m_len >= ip_end))
					goto m_len_done;
			} while (ip[m_len] == m_pos[m_len]);
		}
#endif
		}
m_len_done:

		m_off = ip - m_pos;
		ip += m_len;
		if (m_len <= M2_MAX_LEN && m_off <= M2_MAX_OFFSET) {
			m_off -= 1;
			*op++ = (((m_len - 1) << 5) | ((m_off & 7) << 2));
			*op++ = (m_off >> 3);
		} else if (m_off <= M3_MAX_OFFSET) {
			m_off -= 1;
			if (m_len <= M3_MAX_LEN)
				*op++ = (M3_MARKER | (m_len - 2));
			else {
				m_len -= M3_MAX_LEN;
				*op++ = M3_MARKER | 0;
				while (unlikely(m_len > 255)) {
					m_len -= 255;
					*op++ = 0;
				}
				*op++ = (m_len);
			}
			*op++ = (m_off << 2);
			*op++ = (m_off >> 6);
		} else {
			m_off -= 0x4000;
			if (m_len <= M4_MAX_LEN)
				*op++ = (M4_MARKER | ((m_off >> 11) & 8)
						| (m_len - 2));
			else {
				m_len -= M4_MAX_LEN;
				*op++ = (M4_MARKER | ((m_off >> 11) & 8));
				while (unlikely(m_len > 255)) {
					m_len -= 255;
					*op++ = 0;
				}
				*op++ = (m_len);
			}
			*op++ = (m_off << 2);
			*op++ = (m_off >> 6);
		}
		*state_offset = -2;
finished_writing_instruction:
		ii = ip;
		goto next;
	}
	*out_len = op - out;
	return in_end - (ii - ti);
}

int lzogeneric1x_1_compress(const unsigned char *in, size_t in_len,
		     unsigned char *out, size_t *out_len,
		     void *wrkmem, const unsigned char bitstream_version)
{
	const unsigned char *ip = in;
	unsigned char *op = out;
	unsigned char *data_start;
	size_t l = in_len;
	size_t t = 0;
	signed char state_offset = -2;
	unsigned int m4_max_offset;

	// LZO v0 will never write 17 as first byte (except for zero-length
	// input), so this is used to version the bitstream
	if (bitstream_version > 0) {
		*op++ = 17;
		*op++ = bitstream_version;
		m4_max_offset = M4_MAX_OFFSET_V1;
	} else {
		m4_max_offset = M4_MAX_OFFSET_V0;
	}

	data_start = op;

	while (l > 20) {
		size_t ll = l <= (m4_max_offset + 1) ? l : (m4_max_offset + 1);
		uintptr_t ll_end = (uintptr_t) ip + ll;
		if ((ll_end + ((t + ll) >> 5)) <= ll_end)
			break;
		BUILD_BUG_ON(D_SIZE * sizeof(lzo_dict_t) > LZO1X_1_MEM_COMPRESS);
		memset(wrkmem, 0, D_SIZE * sizeof(lzo_dict_t));
		t = lzo1x_1_do_compress(ip, ll, op, out_len, t, wrkmem,
					&state_offset, bitstream_version);
		ip += ll;
		op += *out_len;
		l  -= ll;
	}
	t += l;

	if (t > 0) {
		const unsigned char *ii = in + in_len - t;

		if (op == data_start && t <= 238) {
			*op++ = (17 + t);
		} else if (t <= 3) {
			op[state_offset] |= t;
		} else if (t <= 18) {
			*op++ = (t - 3);
		} else {
			size_t tt = t - 18;
			*op++ = 0;
			while (tt > 255) {
				tt -= 255;
				*op++ = 0;
			}
			*op++ = tt;
		}
		if (t >= 16) do {
			COPY8(op, ii);
			COPY8(op + 8, ii + 8);
			op += 16;
			ii += 16;
			t -= 16;
		} while (t >= 16);
		if (t > 0) do {
			*op++ = *ii++;
		} while (--t > 0);
	}

	*op++ = M4_MARKER | 1;
	*op++ = 0;
	*op++ = 0;

	*out_len = op - out;
	return LZO_E_OK;
}

int lzo1x_1_compress(const unsigned char *in, size_t in_len,
		     unsigned char *out, size_t *out_len,
		     void *wrkmem)
{
	return lzogeneric1x_1_compress(in, in_len, out, out_len, wrkmem, 0);
}

int lzorle1x_1_compress(const unsigned char *in, size_t in_len,
		     unsigned char *out, size_t *out_len,
		     void *wrkmem)
{
	return lzogeneric1x_1_compress(in, in_len, out, out_len,
				       wrkmem, LZO_VERSION);
}

EXPORT_SYMBOL_GPL(lzo1x_1_compress);
EXPORT_SYMBOL_GPL(lzorle1x_1_compress);

MODULE_LICENSE("GPL");
MODULE_DESCRIPTION("LZO1X-1 Compressor");
Commit	Line	Data
09c434b8	1	// SPDX-License-Identifier: GPL-2.0-only
64c70b1c	2	/*
8b975bd3	3	* LZO1X Compressor from LZO
64c70b1c	4	*
8b975bd3	5	* Copyright (C) 1996-2012 Markus F.X.J. Oberhumer <markus@oberhumer.com>
64c70b1c RP	6	*
	7	* The full LZO package can be found at:
	8	* http://www.oberhumer.com/opensource/lzo/
	9	*
8b975bd3	10	* Changed for Linux kernel use by:
64c70b1c RP	11	* Nitin Gupta <nitingupta910@gmail.com>
	12	* Richard Purdie <rpurdie@openedhand.com>
	13	*/
	14
	15	#include <linux/module.h>
	16	#include <linux/kernel.h>
64c70b1c	17	#include <asm/unaligned.h>
8b975bd3	18	#include <linux/lzo.h>
64c70b1c RP	19	#include "lzodefs.h"
	20
	21	static noinline size_t
8b975bd3 MO	22	lzo1x_1_do_compress(const unsigned char *in, size_t in_len,
8b975bd3 MO	23	unsigned char out, size_t out_len,
45ec975e DR	24	size_t ti, void wrkmem, signed char state_offset,
45ec975e DR	25	const unsigned char bitstream_version)
64c70b1c	26	{
8b975bd3 MO	27	const unsigned char *ip;
8b975bd3 MO	28	unsigned char *op;
64c70b1c	29	const unsigned char * const in_end = in + in_len;
8b975bd3 MO	30	const unsigned char * const ip_end = in + in_len - 20;
	31	const unsigned char *ii;
	32	lzo_dict_t * const dict = (lzo_dict_t *) wrkmem;
64c70b1c	33
8b975bd3 MO	34	op = out;
	35	ip = in;
	36	ii = ip;
	37	ip += ti < 4 ? 4 - ti : 0;
64c70b1c RP	38
64c70b1c RP	39	for (;;) {
5ee4014a	40	const unsigned char *m_pos = NULL;
8b975bd3 MO	41	size_t t, m_len, m_off;
8b975bd3 MO	42	u32 dv;
5ee4014a	43	u32 run_length = 0;
64c70b1c	44	literal:
8b975bd3 MO	45	ip += 1 + ((ip - ii) >> 5);
8b975bd3 MO	46	next:
64c70b1c RP	47	if (unlikely(ip >= ip_end))
64c70b1c RP	48	break;
8b975bd3	49	dv = get_unaligned_le32(ip);
5ee4014a	50
45ec975e	51	if (dv == 0 && bitstream_version) {
5ee4014a DR	52	const unsigned char *ir = ip + 4;
	53	const unsigned char *limit = ip_end
	54	< (ip + MAX_ZERO_RUN_LENGTH + 1)
	55	? ip_end : ip + MAX_ZERO_RUN_LENGTH + 1;
	56	#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && \
	57	defined(LZO_FAST_64BIT_MEMORY_ACCESS)
	58	u64 dv64;
	59
	60	for (; (ir + 32) <= limit; ir += 32) {
	61	dv64 = get_unaligned((u64 *)ir);
	62	dv64 \|= get_unaligned((u64 *)ir + 1);
	63	dv64 \|= get_unaligned((u64 *)ir + 2);
	64	dv64 \|= get_unaligned((u64 *)ir + 3);
	65	if (dv64)
	66	break;
	67	}
	68	for (; (ir + 8) <= limit; ir += 8) {
	69	dv64 = get_unaligned((u64 *)ir);
	70	if (dv64) {
	71	# if defined(__LITTLE_ENDIAN)
	72	ir += __builtin_ctzll(dv64) >> 3;
	73	# elif defined(__BIG_ENDIAN)
	74	ir += __builtin_clzll(dv64) >> 3;
	75	# else
	76	# error "missing endian definition"
	77	# endif
	78	break;
	79	}
	80	}
	81	#else
	82	while ((ir < (const unsigned char *)
	83	ALIGN((uintptr_t)ir, 4)) &&
	84	(ir < limit) && (*ir == 0))
	85	ir++;
09b35b41 DR	86	if (IS_ALIGNED((uintptr_t)ir, 4)) {
	87	for (; (ir + 4) <= limit; ir += 4) {
	88	dv = ((u32 )ir);
	89	if (dv) {
5ee4014a	90	# if defined(__LITTLE_ENDIAN)
09b35b41	91	ir += __builtin_ctz(dv) >> 3;
5ee4014a	92	# elif defined(__BIG_ENDIAN)
09b35b41	93	ir += __builtin_clz(dv) >> 3;
5ee4014a DR	94	# else
	95	# error "missing endian definition"
	96	# endif
09b35b41 DR	97	break;
09b35b41 DR	98	}
5ee4014a DR	99	}
	100	}
	101	#endif
	102	while (likely(ir < limit) && unlikely(*ir == 0))
	103	ir++;
	104	run_length = ir - ip;
	105	if (run_length > MAX_ZERO_RUN_LENGTH)
	106	run_length = MAX_ZERO_RUN_LENGTH;
	107	} else {
	108	t = ((dv * 0x1824429d) >> (32 - D_BITS)) & D_MASK;
	109	m_pos = in + dict[t];
	110	dict[t] = (lzo_dict_t) (ip - in);
	111	if (unlikely(dv != get_unaligned_le32(m_pos)))
	112	goto literal;
	113	}
64c70b1c	114
8b975bd3 MO	115	ii -= ti;
	116	ti = 0;
	117	t = ip - ii;
	118	if (t != 0) {
64c70b1c	119	if (t <= 3) {
5ee4014a	120	op[*state_offset] \|= t;
8b975bd3 MO	121	COPY4(op, ii);
	122	op += t;
	123	} else if (t <= 16) {
64c70b1c	124	*op++ = (t - 3);
8b975bd3 MO	125	COPY8(op, ii);
	126	COPY8(op + 8, ii + 8);
	127	op += t;
64c70b1c	128	} else {
8b975bd3 MO	129	if (t <= 18) {
	130	*op++ = (t - 3);
	131	} else {
	132	size_t tt = t - 18;
64c70b1c	133	*op++ = 0;
8b975bd3 MO	134	while (unlikely(tt > 255)) {
	135	tt -= 255;
	136	*op++ = 0;
	137	}
	138	*op++ = tt;
64c70b1c	139	}
8b975bd3 MO	140	do {
	141	COPY8(op, ii);
	142	COPY8(op + 8, ii + 8);
	143	op += 16;
	144	ii += 16;
	145	t -= 16;
	146	} while (t >= 16);
	147	if (t > 0) do {
	148	op++ = ii++;
	149	} while (--t > 0);
64c70b1c	150	}
64c70b1c RP	151	}
64c70b1c RP	152
5ee4014a DR	153	if (unlikely(run_length)) {
	154	ip += run_length;
	155	run_length -= MIN_ZERO_RUN_LENGTH;
	156	put_unaligned_le32((run_length << 21) \| 0xfffc18
	157	\| (run_length & 0x7), op);
	158	op += 4;
	159	run_length = 0;
	160	*state_offset = -3;
	161	goto finished_writing_instruction;
	162	}
	163
8b975bd3 MO	164	m_len = 4;
	165	{
	166	#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && defined(LZO_USE_CTZ64)
	167	u64 v;
	168	v = get_unaligned((const u64 *) (ip + m_len)) ^
	169	get_unaligned((const u64 *) (m_pos + m_len));
	170	if (unlikely(v == 0)) {
	171	do {
	172	m_len += 8;
	173	v = get_unaligned((const u64 *) (ip + m_len)) ^
	174	get_unaligned((const u64 *) (m_pos + m_len));
	175	if (unlikely(ip + m_len >= ip_end))
	176	goto m_len_done;
	177	} while (v == 0);
	178	}
	179	# if defined(__LITTLE_ENDIAN)
	180	m_len += (unsigned) __builtin_ctzll(v) / 8;
	181	# elif defined(__BIG_ENDIAN)
	182	m_len += (unsigned) __builtin_clzll(v) / 8;
	183	# else
	184	# error "missing endian definition"
	185	# endif
	186	#elif defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) && defined(LZO_USE_CTZ32)
	187	u32 v;
	188	v = get_unaligned((const u32 *) (ip + m_len)) ^
	189	get_unaligned((const u32 *) (m_pos + m_len));
	190	if (unlikely(v == 0)) {
	191	do {
	192	m_len += 4;
	193	v = get_unaligned((const u32 *) (ip + m_len)) ^
	194	get_unaligned((const u32 *) (m_pos + m_len));
	195	if (v != 0)
	196	break;
	197	m_len += 4;
	198	v = get_unaligned((const u32 *) (ip + m_len)) ^
	199	get_unaligned((const u32 *) (m_pos + m_len));
	200	if (unlikely(ip + m_len >= ip_end))
	201	goto m_len_done;
	202	} while (v == 0);
	203	}
	204	# if defined(__LITTLE_ENDIAN)
	205	m_len += (unsigned) __builtin_ctz(v) / 8;
	206	# elif defined(__BIG_ENDIAN)
	207	m_len += (unsigned) __builtin_clz(v) / 8;
	208	# else
	209	# error "missing endian definition"
	210	# endif
	211	#else
	212	if (unlikely(ip[m_len] == m_pos[m_len])) {
	213	do {
	214	m_len += 1;
	215	if (ip[m_len] != m_pos[m_len])
	216	break;
	217	m_len += 1;
	218	if (ip[m_len] != m_pos[m_len])
	219	break;
	220	m_len += 1;
	221	if (ip[m_len] != m_pos[m_len])
	222	break;
	223	m_len += 1;
	224	if (ip[m_len] != m_pos[m_len])
	225	break;
	226	m_len += 1;
	227	if (ip[m_len] != m_pos[m_len])
228	break;
229	m_len += 1;
230	if (ip[m_len] != m_pos[m_len])
231	break;
232	m_len += 1;
233	if (ip[m_len] != m_pos[m_len])
234	break;
235	m_len += 1;
236	if (unlikely(ip + m_len >= ip_end))
237	goto m_len_done;
238	} while (ip[m_len] == m_pos[m_len]);
239	}
240	#endif
241	}
242	m_len_done:
64c70b1c	243
8b975bd3 MO	244	m_off = ip - m_pos;
8b975bd3 MO	245	ip += m_len;
8b975bd3 MO	246	if (m_len <= M2_MAX_LEN && m_off <= M2_MAX_OFFSET) {
	247	m_off -= 1;
	248	*op++ = (((m_len - 1) << 5) \| ((m_off & 7) << 2));
	249	*op++ = (m_off >> 3);
	250	} else if (m_off <= M3_MAX_OFFSET) {
	251	m_off -= 1;
	252	if (m_len <= M3_MAX_LEN)
64c70b1c	253	*op++ = (M3_MARKER \| (m_len - 2));
8b975bd3 MO	254	else {
	255	m_len -= M3_MAX_LEN;
	256	*op++ = M3_MARKER \| 0;
	257	while (unlikely(m_len > 255)) {
	258	m_len -= 255;
	259	*op++ = 0;
	260	}
	261	*op++ = (m_len);
64c70b1c	262	}
8b975bd3 MO	263	*op++ = (m_off << 2);
8b975bd3 MO	264	*op++ = (m_off >> 6);
64c70b1c	265	} else {
8b975bd3 MO	266	m_off -= 0x4000;
	267	if (m_len <= M4_MAX_LEN)
	268	*op++ = (M4_MARKER \| ((m_off >> 11) & 8)
64c70b1c	269	\| (m_len - 2));
8b975bd3 MO	270	else {
	271	m_len -= M4_MAX_LEN;
	272	*op++ = (M4_MARKER \| ((m_off >> 11) & 8));
	273	while (unlikely(m_len > 255)) {
	274	m_len -= 255;
	275	*op++ = 0;
64c70b1c	276	}
8b975bd3	277	*op++ = (m_len);
64c70b1c	278	}
8b975bd3	279	*op++ = (m_off << 2);
64c70b1c RP	280	*op++ = (m_off >> 6);
64c70b1c RP	281	}
5ee4014a DR	282	*state_offset = -2;
	283	finished_writing_instruction:
	284	ii = ip;
8b975bd3	285	goto next;
64c70b1c	286	}
64c70b1c	287	*out_len = op - out;
8b975bd3	288	return in_end - (ii - ti);
64c70b1c RP	289	}
64c70b1c RP	290
45ec975e	291	int lzogeneric1x_1_compress(const unsigned char *in, size_t in_len,
8b975bd3	292	unsigned char out, size_t out_len,
45ec975e	293	void *wrkmem, const unsigned char bitstream_version)
64c70b1c	294	{
8b975bd3	295	const unsigned char *ip = in;
64c70b1c	296	unsigned char *op = out;
b11ed18e	297	unsigned char *data_start;
8b975bd3 MO	298	size_t l = in_len;
8b975bd3 MO	299	size_t t = 0;
5ee4014a	300	signed char state_offset = -2;
45ec975e	301	unsigned int m4_max_offset;
5ee4014a	302
b11ed18e DR	303	// LZO v0 will never write 17 as first byte (except for zero-length
b11ed18e DR	304	// input), so this is used to version the bitstream
45ec975e DR	305	if (bitstream_version > 0) {
	306	*op++ = 17;
	307	*op++ = bitstream_version;
	308	m4_max_offset = M4_MAX_OFFSET_V1;
	309	} else {
	310	m4_max_offset = M4_MAX_OFFSET_V0;
	311	}
64c70b1c	312
b11ed18e DR	313	data_start = op;
b11ed18e DR	314
8b975bd3	315	while (l > 20) {
45ec975e	316	size_t ll = l <= (m4_max_offset + 1) ? l : (m4_max_offset + 1);
8b975bd3 MO	317	uintptr_t ll_end = (uintptr_t) ip + ll;
	318	if ((ll_end + ((t + ll) >> 5)) <= ll_end)
	319	break;
	320	BUILD_BUG_ON(D_SIZE * sizeof(lzo_dict_t) > LZO1X_1_MEM_COMPRESS);
	321	memset(wrkmem, 0, D_SIZE * sizeof(lzo_dict_t));
45ec975e DR	322	t = lzo1x_1_do_compress(ip, ll, op, out_len, t, wrkmem,
45ec975e DR	323	&state_offset, bitstream_version);
8b975bd3	324	ip += ll;
64c70b1c	325	op += *out_len;
8b975bd3	326	l -= ll;
64c70b1c	327	}
8b975bd3	328	t += l;
64c70b1c RP	329
64c70b1c RP	330	if (t > 0) {
8b975bd3	331	const unsigned char *ii = in + in_len - t;
64c70b1c	332
b11ed18e	333	if (op == data_start && t <= 238) {
64c70b1c RP	334	*op++ = (17 + t);
64c70b1c RP	335	} else if (t <= 3) {
5ee4014a	336	op[state_offset] \|= t;
64c70b1c RP	337	} else if (t <= 18) {
	338	*op++ = (t - 3);
	339	} else {
	340	size_t tt = t - 18;
64c70b1c RP	341	*op++ = 0;
	342	while (tt > 255) {
	343	tt -= 255;
	344	*op++ = 0;
	345	}
64c70b1c RP	346	*op++ = tt;
64c70b1c RP	347	}
8b975bd3 MO	348	if (t >= 16) do {
	349	COPY8(op, ii);
	350	COPY8(op + 8, ii + 8);
	351	op += 16;
	352	ii += 16;
	353	t -= 16;
	354	} while (t >= 16);
	355	if (t > 0) do {
64c70b1c RP	356	op++ = ii++;
	357	} while (--t > 0);
	358	}
	359
	360	*op++ = M4_MARKER \| 1;
	361	*op++ = 0;
	362	*op++ = 0;
	363
	364	*out_len = op - out;
	365	return LZO_E_OK;
	366	}
45ec975e DR	367
	368	int lzo1x_1_compress(const unsigned char *in, size_t in_len,
	369	unsigned char out, size_t out_len,
	370	void *wrkmem)
	371	{
	372	return lzogeneric1x_1_compress(in, in_len, out, out_len, wrkmem, 0);
	373	}
	374
	375	int lzorle1x_1_compress(const unsigned char *in, size_t in_len,
	376	unsigned char out, size_t out_len,
	377	void *wrkmem)
	378	{
	379	return lzogeneric1x_1_compress(in, in_len, out, out_len,
	380	wrkmem, LZO_VERSION);
	381	}
	382
64c70b1c	383	EXPORT_SYMBOL_GPL(lzo1x_1_compress);
45ec975e	384	EXPORT_SYMBOL_GPL(lzorle1x_1_compress);
64c70b1c RP	385
	386	MODULE_LICENSE("GPL");
	387	MODULE_DESCRIPTION("LZO1X-1 Compressor");