[dm-devel] [PATCH v2 3/6] multipath: print warning if multipathd is not running.

[Benjamin Marzinski]

If multipath notices that multipath devices exist or were created, and
multipathd is not running, it now prints a warning message, so users are
notified of the issue.

Signed-off-by: Benjamin Marzinski <bmarzins at redhat.com>
---
 libmultipath/configure.c          |  3 ++-
 libmultipath/configure.h          |  1 +
 libmultipath/libmultipath.version |  5 +++++
 multipath/main.c                  | 14 ++++++++++++--
 4 files changed, 20 insertions(+), 3 deletions(-)

diff --git a/libmultipath/configure.c b/libmultipath/configure.c
index 12278640..2f417914 100644
--- a/libmultipath/configure.c
+++ b/libmultipath/configure.c
@@ -1082,7 +1082,8 @@ deadmap (struct multipath * mpp)
 	return 1; /* dead */
 }
 
-int check_daemon(void)
+extern int
+check_daemon(void)
 {
 	int fd;
 	char *reply;
diff --git a/libmultipath/configure.h b/libmultipath/configure.h
index 92a5aba6..efe18b7d 100644
--- a/libmultipath/configure.h
+++ b/libmultipath/configure.h
@@ -59,3 +59,4 @@ struct udev_device *get_udev_device(const char *dev, enum devtypes dev_type);
 void trigger_paths_udev_change(struct multipath *mpp, bool is_mpath);
 void trigger_partitions_udev_change(struct udev_device *dev, const char *action,
 				    int len);
+int check_daemon(void);
diff --git a/libmultipath/libmultipath.version b/libmultipath/libmultipath.version
index 1d84d97c..7b48265f 100644
--- a/libmultipath/libmultipath.version
+++ b/libmultipath/libmultipath.version
@@ -285,3 +285,8 @@ global:
 	print_strbuf;
 	truncate_strbuf;
 } LIBMULTIPATH_8.0.0;
+
+LIBMULTIPATH_8.2.0 {
+global:
+	check_daemon;
+} LIBMULTIPATH_8.1.0;
diff --git a/multipath/main.c b/multipath/main.c
index 8fc0e15f..6c70760f 100644
--- a/multipath/main.c
+++ b/multipath/main.c
@@ -456,6 +456,7 @@ configure (struct config *conf, enum mpath_cmds cmd,
 {
 	vector curmp = NULL;
 	vector pathvec = NULL;
+	vector newmp = NULL;
 	int r = RTVL_FAIL, rc;
 	int di_flag = 0;
 	char * refwwid = NULL;
@@ -466,8 +467,9 @@ configure (struct config *conf, enum mpath_cmds cmd,
 	 */
 	curmp = vector_alloc();
 	pathvec = vector_alloc();
+	newmp = vector_alloc();
 
-	if (!curmp || !pathvec) {
+	if (!curmp || !pathvec || !newmp) {
 		condlog(0, "can not allocate memory");
 		goto out;
 	}
@@ -569,16 +571,24 @@ configure (struct config *conf, enum mpath_cmds cmd,
 	/*
 	 * core logic entry point
 	 */
-	rc = coalesce_paths(&vecs, NULL, refwwid,
+	rc = coalesce_paths(&vecs, newmp, refwwid,
 			   conf->force_reload, cmd);
 	r = rc == CP_RETRY ? RTVL_RETRY : rc == CP_OK ? RTVL_OK : RTVL_FAIL;
 
 out:
+	if (r == RTVL_OK &&
+	    (cmd == CMD_LIST_SHORT || cmd == CMD_LIST_LONG ||
+	     cmd == CMD_CREATE) &&
+	    (VECTOR_SIZE(curmp) > 0 || VECTOR_SIZE(newmp) > 0) &&
+	    !check_daemon())
+		condlog(2, "Warning: multipath devices exist, but multipathd service is not running");
+
 	if (refwwid)
 		FREE(refwwid);
 
 	free_multipathvec(curmp, KEEP_PATHS);
 	vecs.mpvec = NULL;
+	free_multipathvec(newmp, KEEP_PATHS);
 	free_pathvec(pathvec, FREE_PATHS);
 	vecs.pathvec = NULL;
 
-- 
2.17.2