[dm-devel] [PATCH 7/7] multipath: add option to skip multipathd delegation

[Benjamin Marzinski]

Add the -D option to allow users to skip delegating commands to
multipathd.

Signed-off-by: Benjamin Marzinski <bmarzins at redhat.com>
---
 libmultipath/config.h |  1 +
 multipath/main.c      | 15 +++++++++++----
 multipath/multipath.8 | 16 +++++++++++-----
 3 files changed, 23 insertions(+), 9 deletions(-)

diff --git a/libmultipath/config.h b/libmultipath/config.h
index 55569360..92c61a0d 100644
--- a/libmultipath/config.h
+++ b/libmultipath/config.h
@@ -190,6 +190,7 @@ struct config {
 	int ghost_delay;
 	int find_multipaths_timeout;
 	int marginal_pathgroups;
+	int skip_delegate;
 	unsigned int version[3];
 	unsigned int sequence_nr;
 
diff --git a/multipath/main.c b/multipath/main.c
index 6a24e483..0cf7608f 100644
--- a/multipath/main.c
+++ b/multipath/main.c
@@ -130,9 +130,9 @@ usage (char * progname)
 {
 	fprintf (stderr, VERSION_STRING);
 	fprintf (stderr, "Usage:\n");
-	fprintf (stderr, "  %s [-v level] [-B|-d|-i|-q|-r] [-b file] [-p policy] [device]\n", progname);
-	fprintf (stderr, "  %s [-v level] [-R retries] -f device\n", progname);
-	fprintf (stderr, "  %s [-v level] [-R retries] -F\n", progname);
+	fprintf (stderr, "  %s [-v level] [-B|-d|-D|-i|-q|-r] [-b file] [-p policy] [device]\n", progname);
+	fprintf (stderr, "  %s [-v level] [-D|-R retries] -f device\n", progname);
+	fprintf (stderr, "  %s [-v level] [-D|-R retries] -F\n", progname);
 	fprintf (stderr, "  %s [-v level] [-l|-ll] [device]\n", progname);
 	fprintf (stderr, "  %s [-v level] [-a|-w] device\n", progname);
 	fprintf (stderr, "  %s [-v level] -W\n", progname);
@@ -153,6 +153,7 @@ usage (char * progname)
 		"  -C      check if a multipath device has usable paths\n"
 		"  -q      allow queue_if_no_path when multipathd is not running\n"
 		"  -d      dry run, do not create or update devmaps\n"
+		"  -D      Do not delegate command to multipathd\n"
 		"  -t      display the currently used multipathd configuration\n"
 		"  -T      display the multipathd configuration without builtin defaults\n"
 		"  -r      force devmap reload\n"
@@ -817,6 +818,9 @@ int delegate_to_multipathd(enum mpath_cmds cmd,
 	*p = '\0';
 	n = sizeof(command);
 
+	if (conf->skip_delegate)
+		return NOT_DELEGATED;
+
 	if (cmd == CMD_CREATE && conf->force_reload == FORCE_RELOAD_YES) {
 		p += snprintf(p, n, "reconfigure");
 	}
@@ -890,7 +894,7 @@ main (int argc, char *argv[])
 	multipath_conf = conf;
 	conf->retrigger_tries = 0;
 	conf->force_sync = 1;
-	while ((arg = getopt(argc, argv, ":adcChl::eFfM:v:p:b:BrR:itTquUwW")) != EOF ) {
+	while ((arg = getopt(argc, argv, ":adDcChl::eFfM:v:p:b:BrR:itTquUwW")) != EOF ) {
 		switch(arg) {
 		case 1: printf("optarg : %s\n",optarg);
 			break;
@@ -922,6 +926,9 @@ main (int argc, char *argv[])
 			if (cmd == CMD_CREATE)
 				cmd = CMD_DRY_RUN;
 			break;
+		case 'D':
+			conf->skip_delegate = 1;
+			break;
 		case 'f':
 			cmd = CMD_FLUSH_ONE;
 			break;
diff --git a/multipath/multipath.8 b/multipath/multipath.8
index 6fb8645a..16a27363 100644
--- a/multipath/multipath.8
+++ b/multipath/multipath.8
@@ -22,7 +22,7 @@ multipath \- Device mapper target autoconfig.
 .B multipath
 .RB [\| \-v\ \c
 .IR level \|]
-.RB [\| \-B | \-d | \-i | \-q | \-r \|]
+.RB [\| \-B | \-d | \-D | \-i | \-q | \-r \|]
 .RB [\| \-b\ \c
 .IR file \|]
 .RB [\| \-p\ \c
@@ -33,7 +33,7 @@ multipath \- Device mapper target autoconfig.
 .B multipath
 .RB [\| \-v\ \c
 .IR level \|]
-.RB [\| \-R\ \c
+.RB [\| \-D | \-R\ \c
 .IR retries \|]
 .B \-f device
 .
@@ -41,7 +41,7 @@ multipath \- Device mapper target autoconfig.
 .B multipath
 .RB [\| \-v\ \c
 .IR level \|]
-.RB [\| \-R\ \c
+.RB [\| \-D | \-R\ \c
 .IR retries \|]
 .B \-F
 .
@@ -125,11 +125,11 @@ the system.
 Other operation modes are chosen by using one of the following command line switches:
 .TP
 .B \-f
-Flush (remove) a multipath device map specified as parameter, if unused.
+Flush (remove) a multipath device map specified as parameter, if unused. This operation is delegated to the multipathd daemon if it's running.
 .
 .TP
 .B \-F
-Flush (remove) all unused multipath device maps.
+Flush (remove) all unused multipath device maps. This operation is delegated to the multipathd daemon if it's running.
 .
 .TP
 .B \-l
@@ -223,6 +223,12 @@ The verbosity level also controls the level of log and debug messages printed to
 Dry run, do not create or update devmaps.
 .
 .TP
+.B \-D
+Do not delegate operation to multipathd. By default, multipath delegates
+forced reloads and flushes (removes) to multipathd. Setting this option will
+cause the multipath command to execute these operations itself.
+.
+.TP
 .B \-e
 Enable all foreign libraries. This overrides the
 .I enable_foreign 
-- 
2.17.2