From 9759c60f1a1503e48dc5c45a209c3edd5758319f Mon Sep 17 00:00:00 2001 From: Eric Dillmann Date: Wed, 23 Jan 2013 10:54:30 +0100 Subject: [PATCH] Illumos #3035 LZ4 compression support in ZFS and GRUB 3035 LZ4 compression support in ZFS and GRUB Reviewed by: Matthew Ahrens Reviewed by: Christopher Siden Reviewed by: George Wilson Approved by: Christopher Siden References: illumos/illumos-gate@a6f561b4aee75d0d028e7b36b151c8ed8a86bc76 https://www.illumos.org/issues/3035 http://wiki.illumos.org/display/illumos/LZ4+Compression+In+ZFS This patch has been slightly modified from the upstream Illumos version to be compatible with Linux. Due to the very limited stack space in the kernel a lz4 workspace kmem cache is used. Since we are using gcc we are also able to take advantage of the gcc optimized __builtin_ctz functions. Support for GRUB has been dropped from this patch. That code is available but those changes will need to made to the upstream GRUB package. Lastly, several hunks of dead code were dropped for clarity. They include the functions real_LZ4_uncompress(), LZ4_compressBound() and the Visual Studio specific hunks wrapped in _MSC_VER. Ported-by: Eric Dillmann Signed-off-by: Brian Behlendorf Closes #1217 --- include/sys/zio.h | 3 + include/sys/zio_compress.h | 10 + include/zfeature_common.h | 2 + lib/libzpool/Makefile.am | 1 + man/man5/zpool-features.5 | 34 ++ man/man8/zfs.8 | 11 +- module/zcommon/zfs_prop.c | 3 +- module/zfs/Makefile.in | 1 + module/zfs/lz4.c | 1004 ++++++++++++++++++++++++++++++++++ module/zfs/zfeature_common.c | 4 + module/zfs/zfs_ioctl.c | 109 ++++ module/zfs/zio.c | 4 + module/zfs/zio_compress.c | 4 + 13 files changed, 1188 insertions(+), 2 deletions(-) create mode 100644 module/zfs/lz4.c diff --git a/include/sys/zio.h b/include/sys/zio.h index 052797928d..64efde0169 100644 --- a/include/sys/zio.h +++ b/include/sys/zio.h @@ -25,6 +25,7 @@ /* * Copyright 2011 Nexenta Systems, Inc. All rights reserved. * Copyright (c) 2012 by Delphix. All rights reserved. + * Copyright (c) 2013 by Saso Kiselkov. All rights reserved. */ #ifndef _ZIO_H @@ -108,6 +109,7 @@ enum zio_compress { ZIO_COMPRESS_GZIP_8, ZIO_COMPRESS_GZIP_9, ZIO_COMPRESS_ZLE, + ZIO_COMPRESS_LZ4, ZIO_COMPRESS_FUNCTIONS }; @@ -116,6 +118,7 @@ enum zio_compress { #define BOOTFS_COMPRESS_VALID(compress) \ ((compress) == ZIO_COMPRESS_LZJB || \ + (compress) == ZIO_COMPRESS_LZ4 || \ ((compress) == ZIO_COMPRESS_ON && \ ZIO_COMPRESS_ON_VALUE == ZIO_COMPRESS_LZJB) || \ (compress) == ZIO_COMPRESS_OFF) diff --git a/include/sys/zio_compress.h b/include/sys/zio_compress.h index 30bed1a676..49946af4b9 100644 --- a/include/sys/zio_compress.h +++ b/include/sys/zio_compress.h @@ -53,6 +53,12 @@ typedef struct zio_compress_info { extern zio_compress_info_t zio_compress_table[ZIO_COMPRESS_FUNCTIONS]; +/* + * lz4 compression init & free + */ +extern void lz4_init(void); +extern void lz4_fini(void); + /* * Compression routines. */ @@ -68,6 +74,10 @@ extern size_t zle_compress(void *src, void *dst, size_t s_len, size_t d_len, int level); extern int zle_decompress(void *src, void *dst, size_t s_len, size_t d_len, int level); +extern size_t lz4_compress(void *src, void *dst, size_t s_len, size_t d_len, + int level); +extern int lz4_decompress(void *src, void *dst, size_t s_len, size_t d_len, + int level); /* * Compress and decompress data if necessary. diff --git a/include/zfeature_common.h b/include/zfeature_common.h index cb1d02fd7c..8c104e47fa 100644 --- a/include/zfeature_common.h +++ b/include/zfeature_common.h @@ -21,6 +21,7 @@ /* * Copyright (c) 2012 by Delphix. All rights reserved. + * Copyright (c) 2013 by Saso Kiselkov. All rights reserved. */ #ifndef _ZFEATURE_COMMON_H @@ -52,6 +53,7 @@ typedef int (zfeature_func_t)(zfeature_info_t *fi, void *arg); typedef enum spa_feature { SPA_FEATURE_ASYNC_DESTROY, SPA_FEATURE_EMPTY_BPOBJ, + SPA_FEATURE_LZ4_COMPRESS, SPA_FEATURES } spa_feature_t; diff --git a/lib/libzpool/Makefile.am b/lib/libzpool/Makefile.am index 1285af3250..3e62de6371 100644 --- a/lib/libzpool/Makefile.am +++ b/lib/libzpool/Makefile.am @@ -48,6 +48,7 @@ libzpool_la_SOURCES = \ $(top_srcdir)/module/zfs/fm.c \ $(top_srcdir)/module/zfs/gzip.c \ $(top_srcdir)/module/zfs/lzjb.c \ + $(top_srcdir)/module/zfs/lz4.c \ $(top_srcdir)/module/zfs/metaslab.c \ $(top_srcdir)/module/zfs/refcount.c \ $(top_srcdir)/module/zfs/rrwlock.c \ diff --git a/man/man5/zpool-features.5 b/man/man5/zpool-features.5 index 0ab179ef7c..a306e4388f 100644 --- a/man/man5/zpool-features.5 +++ b/man/man5/zpool-features.5 @@ -1,5 +1,6 @@ '\" te .\" Copyright (c) 2012 by Delphix. All rights reserved. +.\" Copyright (c) 2013 by Saso Kiselkov. All rights reserved. .\" The contents of this file are subject to the terms of the Common Development .\" and Distribution License (the "License"). You may not use this file except .\" in compliance with the License. You can obtain a copy of the license at @@ -197,5 +198,38 @@ This feature is \fBactive\fR while there are any filesystems, volumes, or snapshots which were created after enabling this feature. .RE +.sp +.ne 2 +.na +\fB\fBlz4_compress\fR\fR +.ad +.RS 4n +.TS +l l . +GUID org.illumos:lz4_compress +READ\-ONLY COMPATIBLE no +DEPENDENCIES none +.TE + +\fBlz4\fR is a high-performance real-time compression algorithm that +features significantly faster compression and decompression as well as a +higher compression ratio than the older \fBlzjb\fR compression. +Typically, \fBlz4\fR compression is approximately 50% faster on +compressible data and 200% faster on incompressible data than +\fBlzjb\fR. It is also approximately 80% faster on decompression, while +giving approximately 10% better compression ratio. + +When the \fBlz4_compress\fR feature is set to \fBenabled\fR, the +administrator can turn on \fBlz4\fR compression on any dataset on the +pool using the \fBzfs\fR(1M) command. Please note that doing so will +immediately activate the \fBlz4_compress\fR feature on the underlying +pool (even before any data is written). Since this feature is not +read-only compatible, this operation will render the pool unimportable +on systems without support for the \fBlz4_compress\fR feature. At the +moment, this operation cannot be reversed. Booting off of +\fBlz4\fR-compressed root pools is supported. + +.RE + .SH "SEE ALSO" \fBzpool\fR(1M) diff --git a/man/man8/zfs.8 b/man/man8/zfs.8 index 38d54c9cb9..474fde97ac 100644 --- a/man/man8/zfs.8 +++ b/man/man8/zfs.8 @@ -25,6 +25,7 @@ .\" Copyright (c) 2012 by Delphix. All rights reserved. .\" Copyright (c) 2012, Joyent, Inc. All rights reserved. .\" Copyright 2012 Nexenta Systems, Inc. All Rights Reserved. +.\" Copyright (c) 2013 by Saso Kiselkov. All rights reserved. .\" .TH zfs 8 "Jan 10, 2013" "ZFS pool 28, filesystem 5" "System Administration Commands" .SH NAME @@ -731,7 +732,7 @@ Changing this property affects only newly-written data. .ne 2 .mk .na -\fBcompression\fR=\fBon\fR | \fBoff\fR | \fBlzjb\fR | \fBgzip\fR | \fBgzip-\fR\fIN\fR | \fBzle\fR +\fBcompression\fR=\fBon\fR | \fBoff\fR | \fBlzjb\fR | \fBgzip\fR | \fBgzip-\fR\fIN\fR | \fBzle\fR | \fBlz4\fR .ad .sp .6 .RS 4n @@ -741,6 +742,14 @@ The \fBgzip\fR compression algorithm uses the same compression as the \fBgzip\fR .sp The \fBzle\fR (zero-length encoding) compression algorithm is a fast and simple algorithm to eliminate runs of zeroes. .sp +The \fBlz4\fR compression algorithm is a high-performance replacement +for the \fBlzjb\fR algorithm. It features significantly faster +compression and decompression, as well as a moderately higher +compression ratio than \fBlzjb\fR, but can only be used on pools with +the \fBlz4_compress\fR feature set to \fIenabled\fR. See +\fBzpool-features\fR(5) for details on ZFS feature flags and the +\fBlz4_compress\fR feature. +.sp This property can also be referred to by its shortened column name \fBcompress\fR. Changing this property affects only newly-written data. .RE diff --git a/module/zcommon/zfs_prop.c b/module/zcommon/zfs_prop.c index 0a0c25bd41..6aa38382b2 100644 --- a/module/zcommon/zfs_prop.c +++ b/module/zcommon/zfs_prop.c @@ -96,6 +96,7 @@ zfs_prop_init(void) { "gzip-8", ZIO_COMPRESS_GZIP_8 }, { "gzip-9", ZIO_COMPRESS_GZIP_9 }, { "zle", ZIO_COMPRESS_ZLE }, + { "lz4", ZIO_COMPRESS_LZ4 }, { NULL } }; @@ -211,7 +212,7 @@ zfs_prop_init(void) zprop_register_index(ZFS_PROP_COMPRESSION, "compression", ZIO_COMPRESS_DEFAULT, PROP_INHERIT, ZFS_TYPE_FILESYSTEM | ZFS_TYPE_VOLUME, - "on | off | lzjb | gzip | gzip-[1-9] | zle", "COMPRESS", + "on | off | lzjb | gzip | gzip-[1-9] | zle | lz4", "COMPRESS", compress_table); zprop_register_index(ZFS_PROP_SNAPDIR, "snapdir", ZFS_SNAPDIR_HIDDEN, PROP_INHERIT, ZFS_TYPE_FILESYSTEM, diff --git a/module/zfs/Makefile.in b/module/zfs/Makefile.in index f1e32a19dc..81b1680e41 100644 --- a/module/zfs/Makefile.in +++ b/module/zfs/Makefile.in @@ -32,6 +32,7 @@ $(MODULE)-objs += @top_srcdir@/module/zfs/dsl_synctask.o $(MODULE)-objs += @top_srcdir@/module/zfs/fm.o $(MODULE)-objs += @top_srcdir@/module/zfs/gzip.o $(MODULE)-objs += @top_srcdir@/module/zfs/lzjb.o +$(MODULE)-objs += @top_srcdir@/module/zfs/lz4.o $(MODULE)-objs += @top_srcdir@/module/zfs/metaslab.o $(MODULE)-objs += @top_srcdir@/module/zfs/refcount.o $(MODULE)-objs += @top_srcdir@/module/zfs/rrwlock.o diff --git a/module/zfs/lz4.c b/module/zfs/lz4.c new file mode 100644 index 0000000000..b9850c094c --- /dev/null +++ b/module/zfs/lz4.c @@ -0,0 +1,1004 @@ +/* + * LZ4 - Fast LZ compression algorithm + * Header File + * Copyright (C) 2011-2013, Yann Collet. + * BSD 2-Clause License (http://www.opensource.org/licenses/bsd-license.php) + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions are + * met: + * + * * Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * * Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following disclaimer + * in the documentation and/or other materials provided with the + * distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS + * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT + * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR + * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT + * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, + * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT + * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE + * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * You can contact the author at : + * - LZ4 homepage : http://fastcompression.blogspot.com/p/lz4.html + * - LZ4 source repository : http://code.google.com/p/lz4/ + */ + +#include + +static int real_LZ4_compress(const char *source, char *dest, int isize, + int osize); +static int LZ4_uncompress_unknownOutputSize(const char *source, char *dest, + int isize, int maxOutputSize); +static int LZ4_compressCtx(void *ctx, const char *source, char *dest, + int isize, int osize); +static int LZ4_compress64kCtx(void *ctx, const char *source, char *dest, + int isize, int osize); + +static kmem_cache_t *lz4_cache; + +/*ARGSUSED*/ +size_t +lz4_compress(void *s_start, void *d_start, size_t s_len, size_t d_len, int n) +{ + uint32_t bufsiz; + char *dest = d_start; + + ASSERT(d_len >= sizeof (bufsiz)); + + bufsiz = real_LZ4_compress(s_start, &dest[sizeof (bufsiz)], s_len, + d_len - sizeof (bufsiz)); + + /* Signal an error if the compression routine returned zero. */ + if (bufsiz == 0) + return (s_len); + + /* + * Encode the compresed buffer size at the start. We'll need this in + * decompression to counter the effects of padding which might be + * added to the compressed buffer and which, if unhandled, would + * confuse the hell out of our decompression function. + */ + *(uint32_t *)dest = BE_32(bufsiz); + + return (bufsiz + sizeof (bufsiz)); +} + +/*ARGSUSED*/ +int +lz4_decompress(void *s_start, void *d_start, size_t s_len, size_t d_len, int n) +{ + const char *src = s_start; + uint32_t bufsiz = BE_IN32(src); + + /* invalid compressed buffer size encoded at start */ + if (bufsiz + sizeof (bufsiz) > s_len) + return (1); + + /* + * Returns 0 on success (decompression function returned non-negative) + * and non-zero on failure (decompression function returned negative. + */ + return (LZ4_uncompress_unknownOutputSize(&src[sizeof (bufsiz)], + d_start, bufsiz, d_len) < 0); +} + +/* + * LZ4 API Description: + * + * Simple Functions: + * real_LZ4_compress() : + * isize : is the input size. Max supported value is ~1.9GB + * return : the number of bytes written in buffer dest + * or 0 if the compression fails (if LZ4_COMPRESSMIN is set). + * note : destination buffer must be already allocated. + * destination buffer must be sized to handle worst cases + * situations (input data not compressible) worst case size + * evaluation is provided by function LZ4_compressBound(). + * + * real_LZ4_uncompress() : + * osize : is the output size, therefore the original size + * return : the number of bytes read in the source buffer. + * If the source stream is malformed, the function will stop + * decoding and return a negative result, indicating the byte + * position of the faulty instruction. This function never + * writes beyond dest + osize, and is therefore protected + * against malicious data packets. + * note : destination buffer must be already allocated + * + * Advanced Functions + * + * LZ4_compressBound() : + * Provides the maximum size that LZ4 may output in a "worst case" + * scenario (input data not compressible) primarily useful for memory + * allocation of output buffer. + * + * isize : is the input size. Max supported value is ~1.9GB + * return : maximum output size in a "worst case" scenario + * note : this function is limited by "int" range (2^31-1) + * + * LZ4_uncompress_unknownOutputSize() : + * isize : is the input size, therefore the compressed size + * maxOutputSize : is the size of the destination buffer (which must be + * already allocated) + * return : the number of bytes decoded in the destination buffer + * (necessarily <= maxOutputSize). If the source stream is + * malformed, the function will stop decoding and return a + * negative result, indicating the byte position of the faulty + * instruction. This function never writes beyond dest + + * maxOutputSize, and is therefore protected against malicious + * data packets. + * note : Destination buffer must be already allocated. + * This version is slightly slower than real_LZ4_uncompress() + * + * LZ4_compressCtx() : + * This function explicitly handles the CTX memory structure. + * + * ILLUMOS CHANGES: the CTX memory structure must be explicitly allocated + * by the caller (either on the stack or using kmem_cache_alloc). Passing NULL + * isn't valid. + * + * LZ4_compress64kCtx() : + * Same as LZ4_compressCtx(), but specific to small inputs (<64KB). + * isize *Must* be <64KB, otherwise the output will be corrupted. + * + * ILLUMOS CHANGES: the CTX memory structure must be explicitly allocated + * by the caller (either on the stack or using kmem_cache_alloc). Passing NULL + * isn't valid. + */ + +/* + * Tuning parameters + */ + +/* + * COMPRESSIONLEVEL: Increasing this value improves compression ratio + * Lowering this value reduces memory usage. Reduced memory usage + * typically improves speed, due to cache effect (ex: L1 32KB for Intel, + * L1 64KB for AMD). Memory usage formula : N->2^(N+2) Bytes + * (examples : 12 -> 16KB ; 17 -> 512KB) + */ +#define COMPRESSIONLEVEL 12 + +/* + * NOTCOMPRESSIBLE_CONFIRMATION: Decreasing this value will make the + * algorithm skip faster data segments considered "incompressible". + * This may decrease compression ratio dramatically, but will be + * faster on incompressible data. Increasing this value will make + * the algorithm search more before declaring a segment "incompressible". + * This could improve compression a bit, but will be slower on + * incompressible data. The default value (6) is recommended. + */ +#define NOTCOMPRESSIBLE_CONFIRMATION 6 + +/* + * BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE: This will provide a boost to + * performance for big endian cpu, but the resulting compressed stream + * will be incompatible with little-endian CPU. You can set this option + * to 1 in situations where data will stay within closed environment. + * This option is useless on Little_Endian CPU (such as x86). + */ +/* #define BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE 1 */ + +/* + * CPU Feature Detection + */ + +/* 32 or 64 bits ? */ +#if (defined(__x86_64__) || defined(__x86_64) || defined(__amd64__) || \ + defined(__amd64) || defined(__ppc64__) || defined(_WIN64) || \ + defined(__LP64__) || defined(_LP64)) +#define LZ4_ARCH64 1 +#else +#define LZ4_ARCH64 0 +#endif + +/* + * Little Endian or Big Endian? + * Note: overwrite the below #define if you know your architecture endianess. + */ +#if (defined(__BIG_ENDIAN__) || defined(__BIG_ENDIAN) || \ + defined(_BIG_ENDIAN) || defined(_ARCH_PPC) || defined(__PPC__) || \ + defined(__PPC) || defined(PPC) || defined(__powerpc__) || \ + defined(__powerpc) || defined(powerpc) || \ + ((defined(__BYTE_ORDER__)&&(__BYTE_ORDER__ == __ORDER_BIG_ENDIAN__)))) +#define LZ4_BIG_ENDIAN 1 +#else +/* + * Little Endian assumed. PDP Endian and other very rare endian format + * are unsupported. + */ +#endif + +/* + * Unaligned memory access is automatically enabled for "common" CPU, + * such as x86. For others CPU, the compiler will be more cautious, and + * insert extra code to ensure aligned access is respected. If you know + * your target CPU supports unaligned memory access, you may want to + * force this option manually to improve performance + */ +#if defined(__ARM_FEATURE_UNALIGNED) +#define LZ4_FORCE_UNALIGNED_ACCESS 1 +#endif + +/* + * Illumos : we can't use GCC's __builtin_ctz family of builtins in the + * kernel + * Linux : we can use GCC's __builtin_ctz family of builtins in the + * kernel + */ +#undef LZ4_FORCE_SW_BITCOUNT + +/* + * Compiler Options + */ +/* Disable restrict */ +#define restrict + +#define GCC_VERSION (__GNUC__ * 100 + __GNUC_MINOR__) + +#if (GCC_VERSION >= 302) || (__INTEL_COMPILER >= 800) || defined(__clang__) +#define expect(expr, value) (__builtin_expect((expr), (value))) +#else +#define expect(expr, value) (expr) +#endif + +#ifndef likely +#define likely(expr) expect((expr) != 0, 1) +#endif + +#ifndef unlikely +#define unlikely(expr) expect((expr) != 0, 0) +#endif + +#define lz4_bswap16(x) ((unsigned short int) ((((x) >> 8) & 0xffu) | \ + (((x) & 0xffu) << 8))) + +/* Basic types */ +#define BYTE uint8_t +#define U16 uint16_t +#define U32 uint32_t +#define S32 int32_t +#define U64 uint64_t + +#ifndef LZ4_FORCE_UNALIGNED_ACCESS +#pragma pack(1) +#endif + +typedef struct _U16_S { + U16 v; +} U16_S; +typedef struct _U32_S { + U32 v; +} U32_S; +typedef struct _U64_S { + U64 v; +} U64_S; + +#ifndef LZ4_FORCE_UNALIGNED_ACCESS +#pragma pack() +#endif + +#define A64(x) (((U64_S *)(x))->v) +#define A32(x) (((U32_S *)(x))->v) +#define A16(x) (((U16_S *)(x))->v) + +/* + * Constants + */ +#define MINMATCH 4 + +#define HASH_LOG COMPRESSIONLEVEL +#define HASHTABLESIZE (1 << HASH_LOG) +#define HASH_MASK (HASHTABLESIZE - 1) + +#define SKIPSTRENGTH (NOTCOMPRESSIBLE_CONFIRMATION > 2 ? \ + NOTCOMPRESSIBLE_CONFIRMATION : 2) + +#define COPYLENGTH 8 +#define LASTLITERALS 5 +#define MFLIMIT (COPYLENGTH + MINMATCH) +#define MINLENGTH (MFLIMIT + 1) + +#define MAXD_LOG 16 +#define MAX_DISTANCE ((1 << MAXD_LOG) - 1) + +#define ML_BITS 4 +#define ML_MASK ((1U<> ((MINMATCH * 8) - \ + HASH_LOG)) +#define LZ4_HASH_VALUE(p) LZ4_HASH_FUNCTION(A32(p)) +#define LZ4_WILDCOPY(s, d, e) do { LZ4_COPYPACKET(s, d) } while (d < e); +#define LZ4_BLINDCOPY(s, d, l) { BYTE* e = (d) + l; LZ4_WILDCOPY(s, d, e); \ + d = e; } + + +/* Private functions */ +#if LZ4_ARCH64 + +static inline int +LZ4_NbCommonBytes(register U64 val) +{ +#if defined(LZ4_BIG_ENDIAN) +#if defined(__GNUC__) && (GCC_VERSION >= 304) && \ + !defined(LZ4_FORCE_SW_BITCOUNT) + return (__builtin_clzll(val) >> 3); +#else + int r; + if (!(val >> 32)) { + r = 4; + } else { + r = 0; + val >>= 32; + } + if (!(val >> 16)) { + r += 2; + val >>= 8; + } else { + val >>= 24; + } + r += (!val); + return (r); +#endif +#else +#if defined(__GNUC__) && (GCC_VERSION >= 304) && \ + !defined(LZ4_FORCE_SW_BITCOUNT) + return (__builtin_ctzll(val) >> 3); +#else + static const int DeBruijnBytePos[64] = + { 0, 0, 0, 0, 0, 1, 1, 2, 0, 3, 1, 3, 1, 4, 2, 7, 0, 2, 3, 6, 1, 5, + 3, 5, 1, 3, 4, 4, 2, 5, 6, 7, 7, 0, 1, 2, 3, 3, 4, 6, 2, 6, 5, + 5, 3, 4, 5, 6, 7, 1, 2, 4, 6, 4, + 4, 5, 7, 2, 6, 5, 7, 6, 7, 7 + }; + return DeBruijnBytePos[((U64) ((val & -val) * 0x0218A392CDABBD3F)) >> + 58]; +#endif +#endif +} + +#else + +static inline int +LZ4_NbCommonBytes(register U32 val) +{ +#if defined(LZ4_BIG_ENDIAN) +#if defined(__GNUC__) && (GCC_VERSION >= 304) && \ + !defined(LZ4_FORCE_SW_BITCOUNT) + return (__builtin_clz(val) >> 3); +#else + int r; + if (!(val >> 16)) { + r = 2; + val >>= 8; + } else { + r = 0; + val >>= 24; + } + r += (!val); + return (r); +#endif +#else +#if defined(__GNUC__) && (GCC_VERSION >= 304) && \ + !defined(LZ4_FORCE_SW_BITCOUNT) + return (__builtin_ctz(val) >> 3); +#else + static const int DeBruijnBytePos[32] = { + 0, 0, 3, 0, 3, 1, 3, 0, + 3, 2, 2, 1, 3, 2, 0, 1, + 3, 3, 1, 2, 2, 2, 2, 0, + 3, 1, 2, 0, 1, 0, 1, 1 + }; + return DeBruijnBytePos[((U32) ((val & -(S32) val) * 0x077CB531U)) >> + 27]; +#endif +#endif +} + +#endif + +/* Compression functions */ + +/*ARGSUSED*/ +static int +LZ4_compressCtx(void *ctx, const char *source, char *dest, int isize, + int osize) +{ + struct refTables *srt = (struct refTables *)ctx; + HTYPE *HashTable = (HTYPE *) (srt->hashTable); + + const BYTE *ip = (BYTE *) source; + INITBASE(base); + const BYTE *anchor = ip; + const BYTE *const iend = ip + isize; + const BYTE *const oend = (BYTE *) dest + osize; + const BYTE *const mflimit = iend - MFLIMIT; +#define matchlimit (iend - LASTLITERALS) + + BYTE *op = (BYTE *) dest; + + int len, length; + const int skipStrength = SKIPSTRENGTH; + U32 forwardH; + + + /* Init */ + if (isize < MINLENGTH) + goto _last_literals; + + /* First Byte */ + HashTable[LZ4_HASH_VALUE(ip)] = ip - base; + ip++; + forwardH = LZ4_HASH_VALUE(ip); + + /* Main Loop */ + for (;;) { + int findMatchAttempts = (1U << skipStrength) + 3; + const BYTE *forwardIp = ip; + const BYTE *ref; + BYTE *token; + + /* Find a match */ + do { + U32 h = forwardH; + int step = findMatchAttempts++ >> skipStrength; + ip = forwardIp; + forwardIp = ip + step; + + if (unlikely(forwardIp > mflimit)) { + goto _last_literals; + } + + forwardH = LZ4_HASH_VALUE(forwardIp); + ref = base + HashTable[h]; + HashTable[h] = ip - base; + + } while ((ref < ip - MAX_DISTANCE) || (A32(ref) != A32(ip))); + + /* Catch up */ + while ((ip > anchor) && (ref > (BYTE *) source) && + unlikely(ip[-1] == ref[-1])) { + ip--; + ref--; + } + + /* Encode Literal length */ + length = ip - anchor; + token = op++; + + /* Check output limit */ + if (unlikely(op + length + (2 + 1 + LASTLITERALS) + + (length >> 8) > oend)) + return (0); + + if (length >= (int)RUN_MASK) { + *token = (RUN_MASK << ML_BITS); + len = length - RUN_MASK; + for (; len > 254; len -= 255) + *op++ = 255; + *op++ = (BYTE)len; + } else + *token = (length << ML_BITS); + + /* Copy Literals */ + LZ4_BLINDCOPY(anchor, op, length); + + _next_match: + /* Encode Offset */ + LZ4_WRITE_LITTLEENDIAN_16(op, ip - ref); + + /* Start Counting */ + ip += MINMATCH; + ref += MINMATCH; /* MinMatch verified */ + anchor = ip; + while (likely(ip < matchlimit - (STEPSIZE - 1))) { + UARCH diff = AARCH(ref) ^ AARCH(ip); + if (!diff) { + ip += STEPSIZE; + ref += STEPSIZE; + continue; + } + ip += LZ4_NbCommonBytes(diff); + goto _endCount; + } +#if LZ4_ARCH64 + if ((ip < (matchlimit - 3)) && (A32(ref) == A32(ip))) { + ip += 4; + ref += 4; + } +#endif + if ((ip < (matchlimit - 1)) && (A16(ref) == A16(ip))) { + ip += 2; + ref += 2; + } + if ((ip < matchlimit) && (*ref == *ip)) + ip++; + _endCount: + + /* Encode MatchLength */ + len = (ip - anchor); + /* Check output limit */ + if (unlikely(op + (1 + LASTLITERALS) + (len >> 8) > oend)) + return (0); + if (len >= (int)ML_MASK) { + *token += ML_MASK; + len -= ML_MASK; + for (; len > 509; len -= 510) { + *op++ = 255; + *op++ = 255; + } + if (len > 254) { + len -= 255; + *op++ = 255; + } + *op++ = (BYTE)len; + } else + *token += len; + + /* Test end of chunk */ + if (ip > mflimit) { + anchor = ip; + break; + } + /* Fill table */ + HashTable[LZ4_HASH_VALUE(ip - 2)] = ip - 2 - base; + + /* Test next position */ + ref = base + HashTable[LZ4_HASH_VALUE(ip)]; + HashTable[LZ4_HASH_VALUE(ip)] = ip - base; + if ((ref > ip - (MAX_DISTANCE + 1)) && (A32(ref) == A32(ip))) { + token = op++; + *token = 0; + goto _next_match; + } + /* Prepare next loop */ + anchor = ip++; + forwardH = LZ4_HASH_VALUE(ip); + } + + _last_literals: + /* Encode Last Literals */ + { + int lastRun = iend - anchor; + if (op + lastRun + 1 + ((lastRun + 255 - RUN_MASK) / 255) > + oend) + return (0); + if (lastRun >= (int)RUN_MASK) { + *op++ = (RUN_MASK << ML_BITS); + lastRun -= RUN_MASK; + for (; lastRun > 254; lastRun -= 255) { + *op++ = 255; + } + *op++ = (BYTE)lastRun; + } else + *op++ = (lastRun << ML_BITS); + (void) memcpy(op, anchor, iend - anchor); + op += iend - anchor; + } + + /* End */ + return (int)(((char *)op) - dest); +} + + + +/* Note : this function is valid only if isize < LZ4_64KLIMIT */ +#define LZ4_64KLIMIT ((1 << 16) + (MFLIMIT - 1)) +#define HASHLOG64K (HASH_LOG + 1) +#define HASH64KTABLESIZE (1U << HASHLOG64K) +#define LZ4_HASH64K_FUNCTION(i) (((i) * 2654435761U) >> ((MINMATCH*8) - \ + HASHLOG64K)) +#define LZ4_HASH64K_VALUE(p) LZ4_HASH64K_FUNCTION(A32(p)) + +/*ARGSUSED*/ +static int +LZ4_compress64kCtx(void *ctx, const char *source, char *dest, int isize, + int osize) +{ + struct refTables *srt = (struct refTables *)ctx; + U16 *HashTable = (U16 *) (srt->hashTable); + + const BYTE *ip = (BYTE *) source; + const BYTE *anchor = ip; + const BYTE *const base = ip; + const BYTE *const iend = ip + isize; + const BYTE *const oend = (BYTE *) dest + osize; + const BYTE *const mflimit = iend - MFLIMIT; +#define matchlimit (iend - LASTLITERALS) + + BYTE *op = (BYTE *) dest; + + int len, length; + const int skipStrength = SKIPSTRENGTH; + U32 forwardH; + + /* Init */ + if (isize < MINLENGTH) + goto _last_literals; + + /* First Byte */ + ip++; + forwardH = LZ4_HASH64K_VALUE(ip); + + /* Main Loop */ + for (;;) { + int findMatchAttempts = (1U << skipStrength) + 3; + const BYTE *forwardIp = ip; + const BYTE *ref; + BYTE *token; + + /* Find a match */ + do { + U32 h = forwardH; + int step = findMatchAttempts++ >> skipStrength; + ip = forwardIp; + forwardIp = ip + step; + + if (forwardIp > mflimit) { + goto _last_literals; + } + + forwardH = LZ4_HASH64K_VALUE(forwardIp); + ref = base + HashTable[h]; + HashTable[h] = ip - base; + + } while (A32(ref) != A32(ip)); + + /* Catch up */ + while ((ip > anchor) && (ref > (BYTE *) source) && + (ip[-1] == ref[-1])) { + ip--; + ref--; + } + + /* Encode Literal length */ + length = ip - anchor; + token = op++; + + /* Check output limit */ + if (unlikely(op + length + (2 + 1 + LASTLITERALS) + + (length >> 8) > oend)) + return (0); + + if (length >= (int)RUN_MASK) { + *token = (RUN_MASK << ML_BITS); + len = length - RUN_MASK; + for (; len > 254; len -= 255) + *op++ = 255; + *op++ = (BYTE)len; + } else + *token = (length << ML_BITS); + + /* Copy Literals */ + LZ4_BLINDCOPY(anchor, op, length); + + _next_match: + /* Encode Offset */ + LZ4_WRITE_LITTLEENDIAN_16(op, ip - ref); + + /* Start Counting */ + ip += MINMATCH; + ref += MINMATCH; /* MinMatch verified */ + anchor = ip; + while (ip < matchlimit - (STEPSIZE - 1)) { + UARCH diff = AARCH(ref) ^ AARCH(ip); + if (!diff) { + ip += STEPSIZE; + ref += STEPSIZE; + continue; + } + ip += LZ4_NbCommonBytes(diff); + goto _endCount; + } +#if LZ4_ARCH64 + if ((ip < (matchlimit - 3)) && (A32(ref) == A32(ip))) { + ip += 4; + ref += 4; + } +#endif + if ((ip < (matchlimit - 1)) && (A16(ref) == A16(ip))) { + ip += 2; + ref += 2; + } + if ((ip < matchlimit) && (*ref == *ip)) + ip++; + _endCount: + + /* Encode MatchLength */ + len = (ip - anchor); + /* Check output limit */ + if (unlikely(op + (1 + LASTLITERALS) + (len >> 8) > oend)) + return (0); + if (len >= (int)ML_MASK) { + *token += ML_MASK; + len -= ML_MASK; + for (; len > 509; len -= 510) { + *op++ = 255; + *op++ = 255; + } + if (len > 254) { + len -= 255; + *op++ = 255; + } + *op++ = (BYTE)len; + } else + *token += len; + + /* Test end of chunk */ + if (ip > mflimit) { + anchor = ip; + break; + } + /* Fill table */ + HashTable[LZ4_HASH64K_VALUE(ip - 2)] = ip - 2 - base; + + /* Test next position */ + ref = base + HashTable[LZ4_HASH64K_VALUE(ip)]; + HashTable[LZ4_HASH64K_VALUE(ip)] = ip - base; + if (A32(ref) == A32(ip)) { + token = op++; + *token = 0; + goto _next_match; + } + /* Prepare next loop */ + anchor = ip++; + forwardH = LZ4_HASH64K_VALUE(ip); + } + + _last_literals: + /* Encode Last Literals */ + { + int lastRun = iend - anchor; + if (op + lastRun + 1 + ((lastRun + 255 - RUN_MASK) / 255) > + oend) + return (0); + if (lastRun >= (int)RUN_MASK) { + *op++ = (RUN_MASK << ML_BITS); + lastRun -= RUN_MASK; + for (; lastRun > 254; lastRun -= 255) + *op++ = 255; + *op++ = (BYTE)lastRun; + } else + *op++ = (lastRun << ML_BITS); + (void) memcpy(op, anchor, iend - anchor); + op += iend - anchor; + } + + /* End */ + return (int)(((char *)op) - dest); +} + +static int +real_LZ4_compress(const char *source, char *dest, int isize, int osize) +{ + void *ctx; + int result; + + ASSERT(lz4_cache != NULL); + ctx = kmem_cache_alloc(lz4_cache, KM_PUSHPAGE); + + /* + * out of kernel memory, gently fall through - this will disable + * compression in zio_compress_data + */ + if (ctx == NULL) + return (0); + + memset(ctx, 0, sizeof (struct refTables)); + + if (isize < LZ4_64KLIMIT) + result = LZ4_compress64kCtx(ctx, source, dest, isize, osize); + else + result = LZ4_compressCtx(ctx, source, dest, isize, osize); + + kmem_cache_free(lz4_cache, ctx); + return (result); +} + +/* Decompression functions */ + +/* + * Note: The decoding functions real_LZ4_uncompress() and + * LZ4_uncompress_unknownOutputSize() are safe against "buffer overflow" + * attack type. They will never write nor read outside of the provided + * output buffers. LZ4_uncompress_unknownOutputSize() also insures that + * it will never read outside of the input buffer. A corrupted input + * will produce an error result, a negative int, indicating the position + * of the error within input stream. + */ + +static int +LZ4_uncompress_unknownOutputSize(const char *source, char *dest, int isize, + int maxOutputSize) +{ + /* Local Variables */ + const BYTE *restrict ip = (const BYTE *) source; + const BYTE *const iend = ip + isize; + const BYTE *ref; + + BYTE *op = (BYTE *) dest; + BYTE *const oend = op + maxOutputSize; + BYTE *cpy; + + size_t dec32table[] = {0, 3, 2, 3, 0, 0, 0, 0}; +#if LZ4_ARCH64 + size_t dec64table[] = {0, 0, 0, (size_t)-1, 0, 1, 2, 3}; +#endif + + /* Main Loop */ + while (ip < iend) { + unsigned token; + size_t length; + + /* get runlength */ + token = *ip++; + if ((length = (token >> ML_BITS)) == RUN_MASK) { + int s = 255; + while ((ip < iend) && (s == 255)) { + s = *ip++; + length += s; + } + } + /* copy literals */ + cpy = op + length; + if ((cpy > oend - COPYLENGTH) || + (ip + length > iend - COPYLENGTH)) { + if (cpy > oend) + /* Error: writes beyond output buffer */ + goto _output_error; + if (ip + length != iend) + /* + * Error: LZ4 format requires to consume all + * input at this stage + */ + goto _output_error; + (void) memcpy(op, ip, length); + op += length; + /* Necessarily EOF, due to parsing restrictions */ + break; + } + LZ4_WILDCOPY(ip, op, cpy); + ip -= (op - cpy); + op = cpy; + + /* get offset */ + LZ4_READ_LITTLEENDIAN_16(ref, cpy, ip); + ip += 2; + if (ref < (BYTE * const) dest) + /* + * Error: offset creates reference outside of + * destination buffer + */ + goto _output_error; + + /* get matchlength */ + if ((length = (token & ML_MASK)) == ML_MASK) { + while (ip < iend) { + int s = *ip++; + length += s; + if (s == 255) + continue; + break; + } + } + /* copy repeated sequence */ + if (unlikely(op - ref < STEPSIZE)) { +#if LZ4_ARCH64 + size_t dec64 = dec64table[op-ref]; +#else + const int dec64 = 0; +#endif + op[0] = ref[0]; + op[1] = ref[1]; + op[2] = ref[2]; + op[3] = ref[3]; + op += 4; + ref += 4; + ref -= dec32table[op-ref]; + A32(op) = A32(ref); + op += STEPSIZE - 4; + ref -= dec64; + } else { + LZ4_COPYSTEP(ref, op); + } + cpy = op + length - (STEPSIZE - 4); + if (cpy > oend - COPYLENGTH) { + if (cpy > oend) + /* + * Error: request to write outside of + * destination buffer + */ + goto _output_error; + LZ4_SECURECOPY(ref, op, (oend - COPYLENGTH)); + while (op < cpy) + *op++ = *ref++; + op = cpy; + if (op == oend) + /* + * Check EOF (should never happen, since + * last 5 bytes are supposed to be literals) + */ + goto _output_error; + continue; + } + LZ4_SECURECOPY(ref, op, cpy); + op = cpy; /* correction */ + } + + /* end of decoding */ + return (int)(((char *)op) - dest); + + /* write overflow error detected */ + _output_error: + return (int)(-(((char *)ip) - source)); +} + +void +lz4_init(void) +{ + lz4_cache = kmem_cache_create("lz4_cache", + sizeof (struct refTables), 0, NULL, NULL, NULL, NULL, NULL, 0); +} + +void +lz4_fini(void) +{ + if (lz4_cache) { + kmem_cache_destroy(lz4_cache); + lz4_cache = NULL; + } +} + diff --git a/module/zfs/zfeature_common.c b/module/zfs/zfeature_common.c index 40066991b9..2e1dc4e5cd 100644 --- a/module/zfs/zfeature_common.c +++ b/module/zfs/zfeature_common.c @@ -21,6 +21,7 @@ /* * Copyright (c) 2012 by Delphix. All rights reserved. + * Copyright (c) 2013 by Saso Kiselkov. All rights reserved. */ #ifdef _KERNEL @@ -160,4 +161,7 @@ zpool_feature_init(void) zfeature_register(SPA_FEATURE_EMPTY_BPOBJ, "com.delphix:empty_bpobj", "empty_bpobj", "Snapshots use less space.", B_TRUE, B_FALSE, NULL); + zfeature_register(SPA_FEATURE_LZ4_COMPRESS, + "org.illumos:lz4_compress", "lz4_compress", + "LZ4 compression algorithm support.", B_FALSE, B_FALSE, NULL); } diff --git a/module/zfs/zfs_ioctl.c b/module/zfs/zfs_ioctl.c index 98b1dd7941..e804cce085 100644 --- a/module/zfs/zfs_ioctl.c +++ b/module/zfs/zfs_ioctl.c @@ -27,6 +27,7 @@ * Copyright 2011 Nexenta Systems, Inc. All rights reserved. * Copyright (c) 2012 by Delphix. All rights reserved. * Copyright (c) 2012, Joyent, Inc. All rights reserved. + * Copyright (c) 2013 by Saso Kiselkov. All rights reserved. */ #include @@ -75,6 +76,8 @@ #include #include +#include + #include #include "zfs_namecheck.h" @@ -128,6 +131,12 @@ static int zfs_fill_zplprops_root(uint64_t, nvlist_t *, nvlist_t *, boolean_t *); int zfs_set_prop_nvlist(const char *, zprop_source_t, nvlist_t *, nvlist_t **); +static int zfs_prop_activate_feature(dsl_pool_t *dp, zfeature_info_t *feature); +static int zfs_prop_activate_feature_check(void *arg1, void *arg2, + dmu_tx_t *tx); +static void zfs_prop_activate_feature_sync(void *arg1, void *arg2, + dmu_tx_t *tx); + static void history_str_free(char *buf) { @@ -2196,6 +2205,40 @@ zfs_prop_set_special(const char *dsname, zprop_source_t source, } break; } + case ZFS_PROP_COMPRESSION: + { + if (intval == ZIO_COMPRESS_LZ4) { + zfeature_info_t *feature = + &spa_feature_table[SPA_FEATURE_LZ4_COMPRESS]; + spa_t *spa; + dsl_pool_t *dp; + + if ((err = spa_open(dsname, &spa, FTAG)) != 0) + return (err); + + dp = spa->spa_dsl_pool; + + /* + * Setting the LZ4 compression algorithm activates + * the feature. + */ + if (!spa_feature_is_active(spa, feature)) { + if ((err = zfs_prop_activate_feature(dp, + feature)) != 0) { + spa_close(spa, FTAG); + return (err); + } + } + + spa_close(spa, FTAG); + } + /* + * We still want the default set action to be performed in the + * caller, we only performed zfeature settings here. + */ + err = -1; + break; + } default: err = -1; @@ -3416,6 +3459,22 @@ zfs_check_settable(const char *dsname, nvpair_t *pair, cred_t *cr) SPA_VERSION_ZLE_COMPRESSION)) return (ENOTSUP); + if (intval == ZIO_COMPRESS_LZ4) { + zfeature_info_t *feature = + &spa_feature_table[ + SPA_FEATURE_LZ4_COMPRESS]; + spa_t *spa; + + if ((err = spa_open(dsname, &spa, FTAG)) != 0) + return (err); + + if (!spa_feature_is_enabled(spa, feature)) { + spa_close(spa, FTAG); + return (ENOTSUP); + } + spa_close(spa, FTAG); + } + /* * If this is a bootable dataset then * verify that the compression algorithm @@ -3461,6 +3520,56 @@ zfs_check_settable(const char *dsname, nvpair_t *pair, cred_t *cr) return (zfs_secpolicy_setprop(dsname, prop, pair, CRED())); } +/* + * Activates a feature on a pool in response to a property setting. This + * creates a new sync task which modifies the pool to reflect the feature + * as being active. + */ +static int +zfs_prop_activate_feature(dsl_pool_t *dp, zfeature_info_t *feature) +{ + int err; + + /* EBUSY here indicates that the feature is already active */ + err = dsl_sync_task_do(dp, zfs_prop_activate_feature_check, + zfs_prop_activate_feature_sync, dp->dp_spa, feature, 2); + + if (err != 0 && err != EBUSY) + return (err); + else + return (0); +} + +/* + * Checks for a race condition to make sure we don't increment a feature flag + * multiple times. + */ +/*ARGSUSED*/ +static int +zfs_prop_activate_feature_check(void *arg1, void *arg2, dmu_tx_t *tx) +{ + spa_t *spa = arg1; + zfeature_info_t *feature = arg2; + + if (!spa_feature_is_active(spa, feature)) + return (0); + else + return (EBUSY); +} + +/* + * The callback invoked on feature activation in the sync task caused by + * zfs_prop_activate_feature. + */ +static void +zfs_prop_activate_feature_sync(void *arg1, void *arg2, dmu_tx_t *tx) +{ + spa_t *spa = arg1; + zfeature_info_t *feature = arg2; + + spa_feature_incr(spa, feature, tx); +} + /* * Removes properties from the given props list that fail permission checks * needed to clear them and to restore them in case of a receive error. For each diff --git a/module/zfs/zio.c b/module/zfs/zio.c index dab417c206..77b1764d74 100644 --- a/module/zfs/zio.c +++ b/module/zfs/zio.c @@ -210,6 +210,8 @@ zio_init(void) zfs_mg_alloc_failures = MAX((3 * max_ncpus / 2), 8); zio_inject_init(); + + lz4_init(); } void @@ -238,6 +240,8 @@ zio_fini(void) kmem_cache_destroy(zio_cache); zio_inject_fini(); + + lz4_fini(); } /* diff --git a/module/zfs/zio_compress.c b/module/zfs/zio_compress.c index f148977c44..1dc780d4bf 100644 --- a/module/zfs/zio_compress.c +++ b/module/zfs/zio_compress.c @@ -23,6 +23,9 @@ * Copyright 2009 Sun Microsystems, Inc. All rights reserved. * Use is subject to license terms. */ +/* + * Copyright (c) 2013 by Saso Kiselkov. All rights reserved. + */ #include #include @@ -50,6 +53,7 @@ zio_compress_info_t zio_compress_table[ZIO_COMPRESS_FUNCTIONS] = { {gzip_compress, gzip_decompress, 8, "gzip-8"}, {gzip_compress, gzip_decompress, 9, "gzip-9"}, {zle_compress, zle_decompress, 64, "zle"}, + {lz4_compress, lz4_decompress, 0, "lz4"}, }; enum zio_compress