From patchwork Fri Oct 28 02:31:38 2016 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Qu Wenruo X-Patchwork-Id: 9400907 Return-Path: Received: from mail.wl.linuxfoundation.org (pdx-wl-mail.web.codeaurora.org [172.30.200.125]) by pdx-korg-patchwork.web.codeaurora.org (Postfix) with ESMTP id C369E60588 for ; Fri, 28 Oct 2016 02:32:59 +0000 (UTC) Received: from mail.wl.linuxfoundation.org (localhost [127.0.0.1]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id B3B662A0E3 for ; Fri, 28 Oct 2016 02:32:59 +0000 (UTC) Received: by mail.wl.linuxfoundation.org (Postfix, from userid 486) id A7BC42A113; Fri, 28 Oct 2016 02:32:59 +0000 (UTC) X-Spam-Checker-Version: SpamAssassin 3.3.1 (2010-03-16) on pdx-wl-mail.web.codeaurora.org X-Spam-Level: X-Spam-Status: No, score=-6.9 required=2.0 tests=BAYES_00,RCVD_IN_DNSWL_HI autolearn=ham version=3.3.1 Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by mail.wl.linuxfoundation.org (Postfix) with ESMTP id 4499A2A0FF for ; Fri, 28 Oct 2016 02:32:57 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1034323AbcJ1Ccx (ORCPT ); Thu, 27 Oct 2016 22:32:53 -0400 Received: from cn.fujitsu.com ([222.73.24.84]:48358 "EHLO song.cn.fujitsu.com" rhost-flags-OK-FAIL-OK-OK) by vger.kernel.org with ESMTP id S1034305AbcJ1Ccw (ORCPT ); Thu, 27 Oct 2016 22:32:52 -0400 X-IronPort-AV: E=Sophos;i="5.20,367,1444665600"; d="scan'208";a="932115" Received: from unknown (HELO cn.fujitsu.com) ([10.167.250.3]) by song.cn.fujitsu.com with ESMTP; 28 Oct 2016 10:32:04 +0800 Received: from adam-work.localdomain (unknown [10.167.226.34]) by cn.fujitsu.com (Postfix) with ESMTP id 2AC5141B388A; Fri, 28 Oct 2016 10:32:03 +0800 (CST) From: Qu Wenruo To: linux-btrfs@vger.kernel.org, dsterba@suse.cz Subject: [PATCH 02/19] btrfs-progs: raid56: Introduce tables for RAID6 recovery Date: Fri, 28 Oct 2016 10:31:38 +0800 Message-Id: <20161028023155.27336-3-quwenruo@cn.fujitsu.com> X-Mailer: git-send-email 2.10.1 In-Reply-To: <20161028023155.27336-1-quwenruo@cn.fujitsu.com> References: <20161028023155.27336-1-quwenruo@cn.fujitsu.com> MIME-Version: 1.0 X-yoursite-MailScanner-ID: 2AC5141B388A.ABD4E X-yoursite-MailScanner: Found to be clean X-yoursite-MailScanner-From: quwenruo@cn.fujitsu.com Sender: linux-btrfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-btrfs@vger.kernel.org X-Virus-Scanned: ClamAV using ClamSMTP Copied from kernel code with minor modification. Signed-off-by: Qu Wenruo --- .gitignore | 2 + Makefile.in | 12 ++++- mktables.c | 142 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ raid56.h | 7 +++ 4 files changed, 161 insertions(+), 2 deletions(-) create mode 100644 mktables.c diff --git a/.gitignore b/.gitignore index 214103d..2587661 100644 --- a/.gitignore +++ b/.gitignore @@ -2,6 +2,8 @@ *.static.o *.o.d tags +mktables +tables.c .cc-defines.h version.h version diff --git a/Makefile.in b/Makefile.in index 73b2919..a25cda9 100644 --- a/Makefile.in +++ b/Makefile.in @@ -93,7 +93,7 @@ objects = ctree.o disk-io.o kernel-lib/radix-tree.o extent-tree.o print-tree.o \ extent-cache.o extent_io.o volumes.o utils.o repair.o \ qgroup.o raid56.o free-space-cache.o kernel-lib/list_sort.o props.o \ ulist.o qgroup-verify.o backref.o string-table.o task-utils.o \ - inode.o file.o find-root.o free-space-tree.o help.o + inode.o file.o find-root.o free-space-tree.o help.o tables.o cmds_objects = cmds-subvolume.o cmds-filesystem.o cmds-device.o cmds-scrub.o \ cmds-inspect.o cmds-balance.o cmds-send.o cmds-receive.o \ cmds-quota.o cmds-qgroup.o cmds-replace.o cmds-check.o \ @@ -310,6 +310,14 @@ version.h: version.sh version.h.in configure.ac @echo " [SH] $@" $(Q)bash ./config.status --silent $@ +mktables: mktables.c + @echo " [CC] $@" + $(Q)$(CC) $(CFLAGS) $< -o $@ + +tables.c: mktables + @echo " [TABLE] $@" + $(Q)./mktables > $@ || ($(RM) -f $@ && exit 1) + $(libs_shared): $(libbtrfs_objects) $(lib_links) send.h @echo " [LD] $@" $(Q)$(CC) $(CFLAGS) $(libbtrfs_objects) $(LDFLAGS) $(LIBBTRFS_LIBS) \ @@ -430,7 +438,7 @@ clean-all: clean clean-doc clean-gen clean: $(CLEANDIRS) @echo "Cleaning" - $(Q)$(RM) -f -- $(progs) cscope.out *.o *.o.d \ + $(Q)$(RM) -f -- $(progs) cscope.out *.o *.o.d mktables tables.c \ kernel-lib/*.o kernel-lib/*.o.d \ dir-test ioctl-test quick-test send-test library-test library-test-static \ btrfs.static mkfs.btrfs.static \ diff --git a/mktables.c b/mktables.c new file mode 100644 index 0000000..10103f0 --- /dev/null +++ b/mktables.c @@ -0,0 +1,142 @@ +/* -*- linux-c -*- ------------------------------------------------------- * + * + * Copyright 2002-2007 H. Peter Anvin - All Rights Reserved + * + * This file is part of the Linux kernel, and is made available under + * the terms of the GNU General Public License version 2 or (at your + * option) any later version; incorporated herein by reference. + * + * ----------------------------------------------------------------------- */ + +/* + * mktables.c + * + * Make RAID-6 tables. This is a host user space program to be run at + * compile time. + */ + +#include +#include +#include +#include +#include + +static uint8_t gfmul(uint8_t a, uint8_t b) +{ + uint8_t v = 0; + + while (b) { + if (b & 1) + v ^= a; + a = (a << 1) ^ (a & 0x80 ? 0x1d : 0); + b >>= 1; + } + + return v; +} + +static uint8_t gfpow(uint8_t a, int b) +{ + uint8_t v = 1; + + b %= 255; + if (b < 0) + b += 255; + + while (b) { + if (b & 1) + v = gfmul(v, a); + a = gfmul(a, a); + b >>= 1; + } + + return v; +} + +int main(int argc, char *argv[]) +{ + int i, j, k; + uint8_t v; + uint8_t exptbl[256], invtbl[256]; + + printf("#include \"kerncompat.h\"\n"); + + /* Compute multiplication table */ + printf("\nconst u8 __attribute__((aligned(256)))\n" + "raid6_gfmul[256][256] =\n" + "{\n"); + for (i = 0; i < 256; i++) { + printf("\t{\n"); + for (j = 0; j < 256; j += 8) { + printf("\t\t"); + for (k = 0; k < 8; k++) + printf("0x%02x,%c", gfmul(i, j + k), + (k == 7) ? '\n' : ' '); + } + printf("\t},\n"); + } + printf("};\n"); + + /* Compute vector multiplication table */ + printf("\nconst u8 __attribute__((aligned(256)))\n" + "raid6_vgfmul[256][32] =\n" + "{\n"); + for (i = 0; i < 256; i++) { + printf("\t{\n"); + for (j = 0; j < 16; j += 8) { + printf("\t\t"); + for (k = 0; k < 8; k++) + printf("0x%02x,%c", gfmul(i, j + k), + (k == 7) ? '\n' : ' '); + } + for (j = 0; j < 16; j += 8) { + printf("\t\t"); + for (k = 0; k < 8; k++) + printf("0x%02x,%c", gfmul(i, (j + k) << 4), + (k == 7) ? '\n' : ' '); + } + printf("\t},\n"); + } + printf("};\n"); + + /* Compute power-of-2 table (exponent) */ + v = 1; + printf("\nconst u8 __attribute__((aligned(256)))\n" + "raid6_gfexp[256] =\n" "{\n"); + for (i = 0; i < 256; i += 8) { + printf("\t"); + for (j = 0; j < 8; j++) { + exptbl[i + j] = v; + printf("0x%02x,%c", v, (j == 7) ? '\n' : ' '); + v = gfmul(v, 2); + if (v == 1) + v = 0; /* For entry 255, not a real entry */ + } + } + printf("};\n"); + + /* Compute inverse table x^-1 == x^254 */ + printf("\nconst u8 __attribute__((aligned(256)))\n" + "raid6_gfinv[256] =\n" "{\n"); + for (i = 0; i < 256; i += 8) { + printf("\t"); + for (j = 0; j < 8; j++) { + invtbl[i + j] = v = gfpow(i + j, 254); + printf("0x%02x,%c", v, (j == 7) ? '\n' : ' '); + } + } + printf("};\n"); + + /* Compute inv(2^x + 1) (exponent-xor-inverse) table */ + printf("\nconst u8 __attribute__((aligned(256)))\n" + "raid6_gfexi[256] =\n" "{\n"); + for (i = 0; i < 256; i += 8) { + printf("\t"); + for (j = 0; j < 8; j++) + printf("0x%02x,%c", invtbl[exptbl[i + j] ^ 1], + (j == 7) ? '\n' : ' '); + } + printf("};\n"); + + return 0; +} diff --git a/raid56.h b/raid56.h index 54f0cde..a05c14b 100644 --- a/raid56.h +++ b/raid56.h @@ -18,3 +18,10 @@ void raid6_gen_syndrome(int disks, size_t bytes, void **ptrs); int raid5_gen_result(int nr_devs, size_t stripe_len, int dest, void **data); + +/* Galois field tables */ +extern const u8 raid6_gfmul[256][256] __attribute__((aligned(256))); +extern const u8 raid6_vgfmul[256][32] __attribute__((aligned(256))); +extern const u8 raid6_gfexp[256] __attribute__((aligned(256))); +extern const u8 raid6_gfinv[256] __attribute__((aligned(256))); +extern const u8 raid6_gfexi[256] __attribute__((aligned(256)));