From 95f4611621ed7cc5144c68c51adc58409210ad1d Mon Sep 17 00:00:00 2001
From: Changqing Li <changqing.li@windriver.com>
Date: Thu, 26 Sep 2019 16:29:48 +0800
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>

Upstream-Status: Pending

[OP: Rebase to 0.9.3]
Signed-off-by: Ovidiu Panait <ovidiu.panait@windriver.com>

Rebase to 0.9.8
Signed-off-by: Changqing Li <changqing.li@windriver.com>
---
 libmultipath/wwids.c | 44 ++++++++++++++++++++++++++++++++++++++++++++
 libmultipath/wwids.h |  1 +
 2 files changed, 45 insertions(+)

diff --git a/libmultipath/wwids.c b/libmultipath/wwids.c
index aac18c04..68f8e373 100644
--- a/libmultipath/wwids.c
+++ b/libmultipath/wwids.c
@@ -439,3 +439,47 @@ int unmark_failed_wwid(const char *wwid)
 	print_failed_wwid_result("unmark_failed", wwid, r);
 	return r;
 }
+
+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 ee47ad9f..1ed0d85e 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,
