diff options
author | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-28 20:45:52 -0800 |
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committer | Linus Torvalds <torvalds@linux-foundation.org> | 2013-02-28 20:45:52 -0800 |
commit | b0af9cd9aab60ceb17d3ebabb9fdf4ff0a99cf50 (patch) | |
tree | 15c56f48f249c839d4049fdbd71f1bcce14bdd65 /lib/lzo/lzo1x_decompress_safe.c | |
parent | 1e5005979e45337dab9e2c2e4a75ebd71168c004 (diff) | |
parent | 0ec7382036922be063b515b2a3f1d6f7a607392c (diff) |
Merge tag 'lzo-update-signature-20130226' of git://github.com/markus-oberhumer/linux
Pull LZO compression update from Markus Oberhumer:
"Summary:
========
Update the Linux kernel LZO compression and decompression code to the
current upstream version which features significant performance
improvements on modern machines.
Some *synthetic* benchmarks:
============================
x86_64 (Sandy Bridge), gcc-4.6 -O3, Silesia test corpus, 256 kB block-size:
compression speed decompression speed
LZO-2005 : 150 MB/sec 468 MB/sec
LZO-2012 : 434 MB/sec 1210 MB/sec
i386 (Sandy Bridge), gcc-4.6 -O3, Silesia test corpus, 256 kB block-size:
compression speed decompression speed
LZO-2005 : 143 MB/sec 409 MB/sec
LZO-2012 : 372 MB/sec 1121 MB/sec
armv7 (Cortex-A9), Linaro gcc-4.6 -O3, Silesia test corpus, 256 kB block-size:
compression speed decompression speed
LZO-2005 : 27 MB/sec 84 MB/sec
LZO-2012 : 44 MB/sec 117 MB/sec
**LZO-2013-UA : 47 MB/sec 167 MB/sec
Legend:
LZO-2005 : LZO version in current 3.8 kernel (which is based on
the LZO 2.02 release from 2005)
LZO-2012 : updated LZO version available in linux-next
**LZO-2013-UA : updated LZO version available in linux-next plus experimental
ARM Unaligned Access patch. This needs approval
from some ARM maintainer ist NOT YET INCLUDED."
Andrew Morton <akpm@linux-foundation.org> acks it and says:
"There's a new LZ4 on the block which is even faster than the sped-up
LZO, but various filesystems and things use LZO"
* tag 'lzo-update-signature-20130226' of git://github.com/markus-oberhumer/linux:
crypto: testmgr - update LZO compression test vectors
lib/lzo: Update LZO compression to current upstream version
lib/lzo: Rename lzo1x_decompress.c to lzo1x_decompress_safe.c
Diffstat (limited to 'lib/lzo/lzo1x_decompress_safe.c')
-rw-r--r-- | lib/lzo/lzo1x_decompress_safe.c | 237 |
1 files changed, 237 insertions, 0 deletions
diff --git a/lib/lzo/lzo1x_decompress_safe.c b/lib/lzo/lzo1x_decompress_safe.c new file mode 100644 index 00000000000..569985d522d --- /dev/null +++ b/lib/lzo/lzo1x_decompress_safe.c @@ -0,0 +1,237 @@ +/* + * LZO1X Decompressor 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> + */ + +#ifndef STATIC +#include <linux/module.h> +#include <linux/kernel.h> +#endif +#include <asm/unaligned.h> +#include <linux/lzo.h> +#include "lzodefs.h" + +#define HAVE_IP(x) ((size_t)(ip_end - ip) >= (size_t)(x)) +#define HAVE_OP(x) ((size_t)(op_end - op) >= (size_t)(x)) +#define NEED_IP(x) if (!HAVE_IP(x)) goto input_overrun +#define NEED_OP(x) if (!HAVE_OP(x)) goto output_overrun +#define TEST_LB(m_pos) if ((m_pos) < out) goto lookbehind_overrun + +int lzo1x_decompress_safe(const unsigned char *in, size_t in_len, + unsigned char *out, size_t *out_len) +{ + unsigned char *op; + const unsigned char *ip; + size_t t, next; + size_t state = 0; + const unsigned char *m_pos; + const unsigned char * const ip_end = in + in_len; + unsigned char * const op_end = out + *out_len; + + op = out; + ip = in; + + if (unlikely(in_len < 3)) + goto input_overrun; + if (*ip > 17) { + t = *ip++ - 17; + if (t < 4) { + next = t; + goto match_next; + } + goto copy_literal_run; + } + + for (;;) { + t = *ip++; + if (t < 16) { + if (likely(state == 0)) { + if (unlikely(t == 0)) { + while (unlikely(*ip == 0)) { + t += 255; + ip++; + NEED_IP(1); + } + t += 15 + *ip++; + } + t += 3; +copy_literal_run: +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) + if (likely(HAVE_IP(t + 15) && HAVE_OP(t + 15))) { + const unsigned char *ie = ip + t; + unsigned char *oe = op + t; + do { + COPY8(op, ip); + op += 8; + ip += 8; + COPY8(op, ip); + op += 8; + ip += 8; + } while (ip < ie); + ip = ie; + op = oe; + } else +#endif + { + NEED_OP(t); + NEED_IP(t + 3); + do { + *op++ = *ip++; + } while (--t > 0); + } + state = 4; + continue; + } else if (state != 4) { + next = t & 3; + m_pos = op - 1; + m_pos -= t >> 2; + m_pos -= *ip++ << 2; + TEST_LB(m_pos); + NEED_OP(2); + op[0] = m_pos[0]; + op[1] = m_pos[1]; + op += 2; + goto match_next; + } else { + next = t & 3; + m_pos = op - (1 + M2_MAX_OFFSET); + m_pos -= t >> 2; + m_pos -= *ip++ << 2; + t = 3; + } + } else if (t >= 64) { + next = t & 3; + m_pos = op - 1; + m_pos -= (t >> 2) & 7; + m_pos -= *ip++ << 3; + t = (t >> 5) - 1 + (3 - 1); + } else if (t >= 32) { + t = (t & 31) + (3 - 1); + if (unlikely(t == 2)) { + while (unlikely(*ip == 0)) { + t += 255; + ip++; + NEED_IP(1); + } + t += 31 + *ip++; + NEED_IP(2); + } + m_pos = op - 1; + next = get_unaligned_le16(ip); + ip += 2; + m_pos -= next >> 2; + next &= 3; + } else { + m_pos = op; + m_pos -= (t & 8) << 11; + t = (t & 7) + (3 - 1); + if (unlikely(t == 2)) { + while (unlikely(*ip == 0)) { + t += 255; + ip++; + NEED_IP(1); + } + t += 7 + *ip++; + NEED_IP(2); + } + next = get_unaligned_le16(ip); + ip += 2; + m_pos -= next >> 2; + next &= 3; + if (m_pos == op) + goto eof_found; + m_pos -= 0x4000; + } + TEST_LB(m_pos); +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) + if (op - m_pos >= 8) { + unsigned char *oe = op + t; + if (likely(HAVE_OP(t + 15))) { + do { + COPY8(op, m_pos); + op += 8; + m_pos += 8; + COPY8(op, m_pos); + op += 8; + m_pos += 8; + } while (op < oe); + op = oe; + if (HAVE_IP(6)) { + state = next; + COPY4(op, ip); + op += next; + ip += next; + continue; + } + } else { + NEED_OP(t); + do { + *op++ = *m_pos++; + } while (op < oe); + } + } else +#endif + { + unsigned char *oe = op + t; + NEED_OP(t); + op[0] = m_pos[0]; + op[1] = m_pos[1]; + op += 2; + m_pos += 2; + do { + *op++ = *m_pos++; + } while (op < oe); + } +match_next: + state = next; + t = next; +#if defined(CONFIG_HAVE_EFFICIENT_UNALIGNED_ACCESS) + if (likely(HAVE_IP(6) && HAVE_OP(4))) { + COPY4(op, ip); + op += t; + ip += t; + } else +#endif + { + NEED_IP(t + 3); + NEED_OP(t); + while (t > 0) { + *op++ = *ip++; + t--; + } + } + } + +eof_found: + *out_len = op - out; + return (t != 3 ? LZO_E_ERROR : + ip == ip_end ? LZO_E_OK : + ip < ip_end ? LZO_E_INPUT_NOT_CONSUMED : LZO_E_INPUT_OVERRUN); + +input_overrun: + *out_len = op - out; + return LZO_E_INPUT_OVERRUN; + +output_overrun: + *out_len = op - out; + return LZO_E_OUTPUT_OVERRUN; + +lookbehind_overrun: + *out_len = op - out; + return LZO_E_LOOKBEHIND_OVERRUN; +} +#ifndef STATIC +EXPORT_SYMBOL_GPL(lzo1x_decompress_safe); + +MODULE_LICENSE("GPL"); +MODULE_DESCRIPTION("LZO1X Decompressor"); + +#endif |