From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001

From: Benjamin Marzinski <bmarzins@redhat.com>

Date: Fri, 17 Oct 2014 11:20:34 -0500

Subject: [PATCH] RH: add wwids from kernel cmdline mpath.wwids with -A

This patch adds another option to multipath, "-A", which reads

/proc/cmdline for mpath.wwid=<WWID> options, and adds any wwids it finds

to /etc/multipath/wwids.  While this isn't usually important during

normal operation, since these wwids should already be added, it can be

helpful during installation, to make sure that multipath can claim

devices as its own, before LVM or something else makes use of them.  The

patch also execs "/sbin/multipath -A" before running multipathd in

multipathd.service

Signed-off-by: Benjamin Marzinski <bmarzins@redhat.com>

---

 libmultipath/wwids.c          | 44 +++++++++++++++++++++++++++++++++++++++++++

 libmultipath/wwids.h          |  1 +

 multipath/main.c              | 10 ++++++++--

 multipath/multipath.8         |  5 ++++-

 multipathd/multipathd.service |  1 +

 5 files changed, 58 insertions(+), 3 deletions(-)

diff --git a/libmultipath/wwids.c b/libmultipath/wwids.c

index 53e7951..39e08cd 100644

--- a/libmultipath/wwids.c

+++ b/libmultipath/wwids.c

@@ -443,3 +443,47 @@ int op ## _wwid(const char *wwid) \

 declare_failed_wwid_op(is_failed, false)

 declare_failed_wwid_op(mark_failed, true)

 declare_failed_wwid_op(unmark_failed, true)

+

+int remember_cmdline_wwid(void)

+{

+	FILE *f = NULL;

+	char buf[LINE_MAX], *next, *ptr;

+	int ret = 0;

+

+	f = fopen("/proc/cmdline", "re");

+	if (!f) {

+		condlog(0, "can't open /proc/cmdline : %s", strerror(errno));

+		return -1;

+	}

+

+	if (!fgets(buf, sizeof(buf), f)) {

+		if (ferror(f))

+			condlog(0, "read of /proc/cmdline failed : %s",

+				strerror(errno));

+		else

+			condlog(0, "couldn't read /proc/cmdline");

+		fclose(f);

+		return -1;

+	}

+	fclose(f);

+	next = buf;

+	while((ptr = strstr(next, "mpath.wwid="))) {

+		ptr += 11;

+		next = strpbrk(ptr, " \t\n");

+		if (next) {

+			*next = '\0';

+			next++;

+		}

+		if (strlen(ptr)) {

+			if (remember_wwid(ptr) != 0)

+				ret = -1;

+		}

+		else {

+			condlog(0, "empty mpath.wwid kernel command line option");

+			ret = -1;

+		}

+		if (!next)

+			break;

+	}

+	return ret;

+}

diff --git a/libmultipath/wwids.h b/libmultipath/wwids.h

index 0c6ee54..e32a0b0 100644

--- a/libmultipath/wwids.h

+++ b/libmultipath/wwids.h

@@ -17,6 +17,7 @@ int remember_wwid(char *wwid);

 int check_wwids_file(char *wwid, int write_wwid);

 int remove_wwid(char *wwid);

 int replace_wwids(vector mp);

+int remember_cmdline_wwid(void);

 enum {

 	WWID_IS_NOT_FAILED = 0,

diff --git a/multipath/main.c b/multipath/main.c

index ffa5b22..ccb6091 100644

--- a/multipath/main.c

+++ b/multipath/main.c

@@ -120,7 +120,7 @@ usage (char * progname)

 {

 	fprintf (stderr, VERSION_STRING);

 	fprintf (stderr, "Usage:\n");

-	fprintf (stderr, "  %s [-a|-c|-w|-W] [-d] [-r] [-i] [-v lvl] [-p pol] [-b fil] [-q] [dev]\n", progname);

+	fprintf (stderr, "  %s [-a|-A|-c|-w|-W] [-d] [-r] [-i] [-v lvl] [-p pol] [-b fil] [-q] [dev]\n", progname);

 	fprintf (stderr, "  %s -l|-ll|-f [-v lvl] [-b fil] [-R num] [dev]\n", progname);

 	fprintf (stderr, "  %s -F [-v lvl] [-R num]\n", progname);

 	fprintf (stderr, "  %s [-t|-T]\n", progname);

@@ -134,6 +134,8 @@ usage (char * progname)

 		"  -f      flush a multipath device map\n"

 		"  -F      flush all multipath device maps\n"

 		"  -a      add a device wwid to the wwids file\n"

+		"  -A      add devices from kernel command line mpath.wwids\n"

+		"          parameters to wwids file\n"

 		"  -c      check if a device should be a path in a multipath device\n"

 		"  -C      check if a multipath device has usable paths\n"

 		"  -q      allow queue_if_no_path when multipathd is not running\n"

@@ -868,7 +870,7 @@ main (int argc, char *argv[])

 		exit(1);

 	multipath_conf = conf;

 	conf->retrigger_tries = 0;

-	while ((arg = getopt(argc, argv, ":adcChl::FfM:v:p:b:BrR:itTquUwW")) != EOF ) {

+	while ((arg = getopt(argc, argv, ":aAdcChl::FfM:v:p:b:BrR:itTquUwW")) != EOF ) {

 		switch(arg) {

 		case 1: printf("optarg : %s\n",optarg);

 			break;

@@ -938,6 +940,10 @@ main (int argc, char *argv[])

 		case 'T':

 			cmd = CMD_DUMP_CONFIG;

 			break;

+		case 'A':

+			if (remember_cmdline_wwid() != 0)

+				exit(1);

+			exit(0);

 		case 'h':

 			usage(argv[0]);

 			exit(0);

diff --git a/multipath/multipath.8 b/multipath/multipath.8

index b5e5292..5bd5229 100644

--- a/multipath/multipath.8

+++ b/multipath/multipath.8

@@ -25,7 +25,7 @@ multipath \- Device mapper target autoconfig.

 .RB [\| \-b\ \c

 .IR bindings_file \|]

 .RB [\| \-d \|]

-.RB [\| \-h | \-l | \-ll | \-f | \-t | \-T | \-F | \-B | \-c | \-C | \-q | \-r | \-i | \-a | \-u | \-U | \-w | \-W \|]

+.RB [\| \-h | \-l | \-ll | \-f | \-t | \-T | \-F | \-B | \-c | \-C | \-q | \-r | \-i | \-a | \-A | \-u | \-U | \-w | \-W \|]

 .RB [\| \-p\ \c

 .IR failover | multibus | group_by_serial | group_by_prio | group_by_node_name \|]

 .RB [\| \-R\ \c

@@ -141,6 +141,9 @@ Add the WWID for the specified device to the WWIDs file.

 Check if the device specified in the program environment should be

 a path in a multipath device.

 .

+.B \-A

+add wwids from any kernel command line mpath.wwid parameters to the wwids file

+.

 .TP

 .B \-U

 Check if the device specified in the program environment is a multipath device

diff --git a/multipathd/multipathd.service b/multipathd/multipathd.service

index 17434ce..0fbcc46 100644

--- a/multipathd/multipathd.service

+++ b/multipathd/multipathd.service

@@ -15,6 +15,7 @@ Type=notify

 NotifyAccess=main

 LimitCORE=infinity

 ExecStartPre=-/sbin/modprobe -a scsi_dh_alua scsi_dh_emc scsi_dh_rdac dm-multipath

+ExecStartPre=-/sbin/multipath -A

 ExecStart=/sbin/multipathd -d -s

 ExecReload=/sbin/multipathd reconfigure

 TasksMax=infinity

-- 

2.7.4