<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN"> <HTML> <HEAD> <META HTTP-EQUIV="Content-Type" CONTENT="text/html; charset=us-ascii"> <META NAME="Generator" CONTENT="MS Exchange Server version 6.5.7652.24"> <TITLE>RE: [dm-devel] [patch] mpath_prio_pp</TITLE> </HEAD> <BODY>  Hi, We would like to have the below patch committed to the CVS. Purpose of the patch- -- To introduce the prio_callout attribute into the multipath section of the configuration file. -- To implement the preferred path feature in device mapper. Uses of the patch- -- Prio_callout attribute in the multipath section allows users to write callout routines,which can be specific to a LUN. -- When it is known the performance of one of the path is better than the other available paths for a particular LUN, the user can set it as preferred path. -- When there is prior knowledge about the unavailabililty of some paths for a LUN, the user can set some other path as the preferred path. Paths may become unavailable due to controller firmware up gradation, switch replacement, FC replacement etc. Thanks, Veena ________________________________ From: dm-devel-bounces@redhat.com [<A HREF="mailto:dm-devel-bounces@redhat.com">mailto:dm-devel-bounces@redhat.com</A>] On Behalf Of T S, Veena (STSD) Sent: Wednesday, December 05, 2007 8:56 AM To: dm-devel@redhat.com Subject: [dm-devel] [patch] mpath_prio_pp Hi, Below is the patch for the implementation of preferred path feature in the device mapper. Preferred path feature allows the selection of a particular path for a LUN, by making proper priority assignments. mpath_prio_pp is a callout routine for the same.Let me know your comments. Thanks, Veena diff -pNaur multipath-tools-0.4.8/libmultipath/config.h multipath-tools-0.4.8.new/libmultipath/config.h --- multipath-tools-0.4.8/libmultipath/config.h 2007-08-03 02:35:37.000000000 +0530 +++ multipath-tools-0.4.8.new/libmultipath/config.h 2007-11-30 12:40:33.000000000 +0530 @@ -37,6 +37,7 @@ struct mpentry { char * alias; char * getuid; char * selector; + char * getprio; int pgpolicy; int pgfailback; diff -pNaur multipath-tools-0.4.8/libmultipath/dict.c multipath-tools-0.4.8.new/libmultipath/dict.c --- multipath-tools-0.4.8/libmultipath/dict.c 2007-08-03 02:35:37.000000000 +0530 +++ multipath-tools-0.4.8.new/libmultipath/dict.c 2007-11-30 12:13:46.000000000 +0530 @@ -933,9 +933,31 @@ mp_pg_timeout_handler(vector strvec) return 0; } +static int +mp_prio_callout_handler(vector strvec) +{ + struct mpentry * mpe = VECTOR_LAST_SLOT(conf->mptable); + + if(!mpe) + return 1; + + mpe->getprio = set_value(strvec); + + if(!mpe->getprio) + return 1; + + if (strlen(mpe->getprio) == 4 && !strcmp(mpe->getprio, "none")) { + FREE(mpe->getprio); + mpe->getprio = NULL; + } + + return 0; +} + /* * config file keywords printing */ + static int snprint_mp_wwid (char * buff, int len, void * data) { @@ -1068,6 +1090,17 @@ snprint_mp_pg_timeout (char * buff, int } static int +snprint_mp_prio_callout(char * buff, int len, void * data) +{ + struct mpentry * mpe = (struct mpentry *)data; + + if (!mpe->getprio) + return 0; + + return snprintf(buff, len, "%s", mpe->getprio); +} + +static int snprint_hw_vendor (char * buff, int len, void * data) { struct hwentry * hwe = (struct hwentry *)data; @@ -1594,6 +1627,7 @@ init_keywords(void) install_keyword("alias", &alias_handler, &snprint_mp_alias); install_keyword("path_grouping_policy", &mp_pgpolicy_handler, &snprint_mp_path_grouping_policy); install_keyword("path_selector", &mp_selector_handler, &snprint_mp_selector); + install_keyword("prio_callout", &mp_prio_callout_handler, &snprint_mp_prio_callout); install_keyword("failback", &mp_failback_handler, &snprint_mp_failback); install_keyword("rr_weight", &mp_weight_handler, &snprint_mp_rr_weight); install_keyword("no_path_retry", &mp_no_path_retry_handler, &snprint_mp_no_path_retry); diff -pNaur multipath-tools-0.4.8/libmultipath/discovery.c multipath-tools-0.4.8.new/libmultipath/discovery.c --- multipath-tools-0.4.8/libmultipath/discovery.c 2007-08-03 02:35:37.000000000 +0530 +++ multipath-tools-0.4.8.new/libmultipath/discovery.c 2007-11-30 12:18:21.000000000 +0530 @@ -709,8 +709,11 @@ pathinfo (struct path *pp, vector hwtabl * been successfully obtained before. */ if (mask & DI_PRIO && - (pp->state != PATH_DOWN || pp->priority == PRIO_UNDEF)) + (pp->state != PATH_DOWN || pp->priority == PRIO_UNDEF)) { + if( !strlen(pp->wwid)) + get_uid(pp); get_prio(pp); + } if (mask & DI_WWID && !strlen(pp->wwid)) get_uid(pp); diff -pNaur multipath-tools-0.4.8/libmultipath/propsel.c multipath-tools-0.4.8.new/libmultipath/propsel.c --- multipath-tools-0.4.8/libmultipath/propsel.c 2007-08-03 02:35:37.000000000 +0530 +++ multipath-tools-0.4.8.new/libmultipath/propsel.c 2007-11-30 12:45:21.000000000 +0530 @@ -258,7 +258,16 @@ select_getuid (struct path * pp) extern int select_getprio (struct path * pp) -{ +{ + struct mpentry * mpe; + if (mpe = find_mpe(pp->wwid)) { + if (mpe->getprio) { + pp->getprio = mpe->getprio; + condlog(3, "%s: getprio = %s (LUN setting)", pp->dev, pp->getprio); + return 0; + } + } + if (pp->hwe && pp->hwe->getprio) { pp->getprio = pp->hwe->getprio; condlog(3, "%s: getprio = %s (controller setting)", diff -pNaur multipath-tools-0.4.8/path_priority/pp_pref_path/Makefile multipath-tools-0.4.8.new/path_priority/pp_pref_path/Makefile --- multipath-tools-0.4.8/path_priority/pp_pref_path/Makefile 1970-01-01 05:30:00.000000000 +0530 +++ multipath-tools-0.4.8.new/path_priority/pp_pref_path/Makefile 2007-11-30 11:47:21.000000000 +0530 @@ -0,0 +1,25 @@ +EXEC = mpath_prio_pp +BUILD = glibc +OBJS = mpath_prio_pp.o + +TOPDIR = ../.. +include $(TOPDIR)/Makefile.inc + +all: $(BUILD) + +glibc: $(OBJS) + $(CC) -o $(EXEC) $(OBJS) $(LDFLAGS) + +klibc: $(OBJS) + $(CC) -static -o $(EXEC) $(OBJS) + +install: $(EXEC) + install -m 755 $(EXEC) $(DESTDIR)$(bindir)/$(EXEC) + +uninstall: + rm $(DESTDIR)$(bindir)/$(EXEC) +clean: + rm -f *.o $(EXEC) + +%.o: %.c + $(CC) $(CFLAGS) -c -o $@ $< diff -pNaur multipath-tools-0.4.8/path_priority/pp_pref_path/mpath_prio_pp.c multipath-tools-0.4.8.new/path_priority/pp_pref_path/mpath_prio_pp.c --- multipath-tools-0.4.8/path_priority/pp_pref_path/mpath_prio_pp.c 1970-01-01 05:30:00.000000000 +0530 +++ multipath-tools-0.4.8.new/path_priority/pp_pref_path/mpath_prio_pp.c 2007-12-04 16:54:21.000000000 +0530 @@ -0,0 +1,67 @@ + /* + ***************************************************************************** + * * + * (C) Copyright 2007 Hewlett-Packard Development Company, L.P * + * * + * This program is free software; you can redistribute it and/or modify it * + * under the terms of the GNU General Public License as published by the Free* + * Software Foundation; either version 2 of the License, or (at your option)* + * any later version. * + * * + * 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 * + * for more details. * + * * + * You should have received a copy of the GNU General Public License along * + * with this program; if not, write to the Free Software Foundation, Inc., * + * 675 Mass Ave, Cambridge, MA 02139, USA. * + * * + * The copy of the GNU General Public License is available at * + * /opt/hp/HPDMmultipath-tool directoy * + * * + ***************************************************************************** + */ + +/* + * Prioritizer for device mapper,when a path instance is provided as the + * preferred path. + + * This prioritizer assigns a priority value based on the comparison made + * between the preferred path and the path instance for which this is called. + * A priority value of 1 is assigned to the preferred path and 0 to the other + * non-preferred paths. + + * Returns zero on successful assignment of priority and -1 on failure. + * Failure to assign priority can be caused due to invalid pathname or a missing * argument. + */ + +#include<stdio.h> +#include<string.h> +#define HIGH 1 +#define LOW 0 +#define FILE_NAME_SIZE 256 + +int main(int argc, char * argv[]) +{ + + char path[FILE_NAME_SIZE]; + + if(argv[1] && argv[2]) + { + if(!strncmp(argv[2],"/dev/",5)) + strcpy(path,argv[2]+5); + + if(!strcmp(path,argv[1]) || !strcmp(argv[1],argv[2])) + { + printf("%u\n", HIGH); + return 0; + } + else + { + printf("%u\n", LOW); + return 0; + } + } + return -1; +} </BODY> </HTML>