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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-11 08:27:49 +0000 |
commit | ace9429bb58fd418f0c81d4c2835699bddf6bde6 (patch) | |
tree | b2d64bc10158fdd5497876388cd68142ca374ed3 /lib/lzo/lzo1x_compress.c | |
parent | Initial commit. (diff) | |
download | linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.tar.xz linux-ace9429bb58fd418f0c81d4c2835699bddf6bde6.zip |
Adding upstream version 6.6.15.upstream/6.6.15
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to '')
-rw-r--r-- | lib/lzo/lzo1x_compress.c | 398 |
1 files changed, 398 insertions, 0 deletions
diff --git a/lib/lzo/lzo1x_compress.c b/lib/lzo/lzo1x_compress.c new file mode 100644 index 0000000000..9d31e71266 --- /dev/null +++ b/lib/lzo/lzo1x_compress.c @@ -0,0 +1,398 @@ +// 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 = min(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 { + if (unlikely(((m_off & 0x403f) == 0x403f) + && (m_len >= 261) + && (m_len <= 264)) + && likely(bitstream_version)) { + // Under lzo-rle, block copies + // for 261 <= length <= 264 and + // (distance & 0x80f3) == 0x80f3 + // can result in ambiguous + // output. Adjust length + // to 260 to prevent ambiguity. + ip -= m_len - 260; + m_len = 260; + } + 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); +} + +static 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 = min_t(size_t, 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"); |