X-Git-Url: https://git.whamcloud.com/?a=blobdiff_plain;f=lustre%2Fobdclass%2Fmea.c;h=eaa3533d1f637c42ded4d0dd542cc084a11c4482;hb=9f463e30893138845eb571cc32426e8d1e04a9fa;hp=eae602776663f7912328fba450a9eeb1ce64b860;hpb=0ae1c575448dbb0700bc45a88f964645c37a774c;p=fs%2Flustre-release.git diff --git a/lustre/obdclass/mea.c b/lustre/obdclass/mea.c index eae6027..eaa3533 100644 --- a/lustre/obdclass/mea.c +++ b/lustre/obdclass/mea.c @@ -1,43 +1,65 @@ /* -*- mode: c; c-basic-offset: 8; indent-tabs-mode: nil; -*- * vim:expandtab:shiftwidth=8:tabstop=8: * - * Copyright (C) 2002, 2003 Cluster File Systems, Inc. + * GPL HEADER START * - * This file is part of Lustre, http://www.lustre.org. + * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * - * Lustre is free software; you can redistribute it and/or - * modify it under the terms of version 2 of the GNU General Public - * License as published by the Free Software Foundation. + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 only, + * as published by the Free Software Foundation. * - * Lustre is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. + * This program is distributed in the hope that it will be useful, but + * WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU + * General Public License version 2 for more details (a copy is included + * in the LICENSE file that accompanied this code). * - * You should have received a copy of the GNU General Public License - * along with Lustre; if not, write to the Free Software - * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. + * You should have received a copy of the GNU General Public License + * version 2 along with this program; If not, see + * http://www.sun.com/software/products/lustre/docs/GPLv2.pdf + * + * Please contact Sun Microsystems, Inc., 4150 Network Circle, Santa Clara, + * CA 95054 USA or visit www.sun.com if you need additional information or + * have any questions. + * + * GPL HEADER END + */ +/* + * Copyright 2008 Sun Microsystems, Inc. All rights reserved + * Use is subject to license terms. + */ +/* + * This file is part of Lustre, http://www.lustre.org/ + * Lustre is a trademark of Sun Microsystems, Inc. */ #define DEBUG_SUBSYSTEM S_CLASS +#include #ifdef __KERNEL__ #include /* for request_module() */ #include -#include #include #include #include -#else +#else #include -#include -#include +#include #endif -#include +#include +#include +#ifdef __KERNEL__ +#include +#ifdef HAVE_SERVER_SUPPORT +/* LDISKFS_SB() */ +#include +#endif +#endif static int mea_last_char_hash(int count, char *name, int namelen) { unsigned int c; - + c = name[namelen - 1]; if (c == 0) CWARN("looks like wrong len is passed\n"); @@ -55,6 +77,84 @@ static int mea_all_chars_hash(int count, char *name, int namelen) return c; } +#ifdef __KERNEL__ +/* This hash calculate method must be same as the lvar hash method */ + +#define LVAR_HASH_SANDWICH (0) +#define LVAR_HASH_TEA (1) +#define LVAR_HASH_R5 (0) +#define LVAR_HASH_PREFIX (0) + +static __u32 hash_build0(const char *name, int namelen) +{ + __u32 result; + + if (namelen == 0) + return 0; + if (strncmp(name, ".", 1) == 0 && namelen == 1) + return 1; + if (strncmp(name, "..", 2) == 0 && namelen == 2) + return 2; + + if (LVAR_HASH_PREFIX) { + result = 0; + strncpy((void *)&result, + name, min(namelen, (int)sizeof result)); + } else { + struct ldiskfs_dx_hash_info hinfo; + + if (LVAR_HASH_TEA) + hinfo.hash_version = LDISKFS_DX_HASH_TEA; + else + hinfo.hash_version = LDISKFS_DX_HASH_R5; + hinfo.seed = 0; + ldiskfsfs_dirhash(name, namelen, &hinfo); + result = hinfo.hash; + if (LVAR_HASH_SANDWICH) { + __u32 result2; + + hinfo.hash_version = LDISKFS_DX_HASH_TEA; + hinfo.seed = 0; + ldiskfsfs_dirhash(name, namelen, &hinfo); + result2 = hinfo.hash; + result = (0xfc000000 & result2) | (0x03ffffff & result); + } + } + + return result; +} + +enum { + HASH_GRAY_AREA = 1024 +}; + +static __u32 hash_build(const char *name, int namelen) +{ + __u32 hash; + + hash = (hash_build0(name, namelen) << 1) & MAX_HASH_SIZE_32; + if (hash > MAX_HASH_SIZE_32 - HASH_GRAY_AREA) + hash &= HASH_GRAY_AREA - 1; + return hash; +} + +static int mea_hash_segment(int count, const char *name, int namelen) +{ + __u32 hash; + + LASSERT(IS_PO2(MAX_HASH_SIZE_32 + 1)); + + hash = hash_build(name, namelen) / (MAX_HASH_SIZE_32 / count); + LASSERTF(hash < count, "hash %x count %d \n", hash, count); + + return hash; +} +#else +static int mea_hash_segment(int count, char *name, int namelen) +{ + return 0; +} +#endif int raw_name2idx(int hashtype, int count, const char *name, int namelen) { unsigned int c = 0; @@ -65,22 +165,26 @@ int raw_name2idx(int hashtype, int count, const char *name, int namelen) switch (hashtype) { case MEA_MAGIC_LAST_CHAR: - c = mea_last_char_hash(count, (char *) name, namelen); + c = mea_last_char_hash(count, (char *)name, namelen); break; case MEA_MAGIC_ALL_CHARS: - c = mea_all_chars_hash(count, (char *) name, namelen); + c = mea_all_chars_hash(count, (char *)name, namelen); + break; + case MEA_MAGIC_HASH_SEGMENT: + c = mea_hash_segment(count, (char *)name, namelen); break; default: - CERROR("unknown hash type 0x%x\n", hashtype); + CERROR("Unknown hash type 0x%x\n", hashtype); } + LASSERT(c < count); return c; } -int mea_name2idx(struct mea *mea, char *name, int namelen) +int mea_name2idx(struct lmv_stripe_md *mea, const char *name, int namelen) { unsigned int c; - + LASSERT(mea && mea->mea_count); c = raw_name2idx(mea->mea_magic, mea->mea_count, name, namelen); @@ -88,4 +192,3 @@ int mea_name2idx(struct mea *mea, char *name, int namelen) LASSERT(c < mea->mea_count); return c; } -