From db50dbf5692325cfef8fb77e56e1e44af83a022e Mon Sep 17 00:00:00 2001
From: Maurizio Lombardi <mlombard@redhat.com>
Date: Wed, 29 Jun 2022 16:47:30 +0200
Subject: [PATCH 1/7] nvme-cli: nvme gen-hostnqn use partition UUID on IBM
 POWER

Signed-off-by: Maurizio Lombardi <mlombard@redhat.com>
---
 nvme.c | 27 +++++++++++++++++++++++++--
 1 file changed, 25 insertions(+), 2 deletions(-)

diff --git a/nvme.c b/nvme.c
index 5beeac78..0535ed2b 100644
--- a/nvme.c
+++ b/nvme.c
@@ -6516,6 +6516,26 @@ static int admin_passthru(int argc, char **argv, struct command *cmd, struct plu
 	return passthru(argc, argv, NVME_IOCTL_ADMIN_CMD, 1, desc, cmd);
 }
 
+#define PATH_UUID_IBM	"/proc/device-tree/ibm,partition-uuid"
+
+static int uuid_from_device_tree(char *system_uuid)
+{
+	ssize_t len;
+	int f;
+
+	f = open(PATH_UUID_IBM, O_RDONLY);
+	if (f < 0)
+		return -ENXIO;
+
+	memset(system_uuid, 0, 37);
+	len = read(f, system_uuid, 37 - 1);
+	close(f);
+	if (len < 0)
+		return -ENXIO;
+
+	return strlen(system_uuid) ? 0 : -ENXIO;
+}
+
 static int gen_hostnqn_cmd(int argc, char **argv, struct command *command, struct plugin *plugin)
 {
 	int ret;
@@ -6525,8 +6545,11 @@ static int gen_hostnqn_cmd(int argc, char **argv, struct command *command, struc
 #endif
 
 	ret = uuid_from_dmi(uuid_str);
-	if (ret < 0)
-		ret = uuid_from_systemd(uuid_str);
+	if (ret < 0) {
+		ret = uuid_from_device_tree(uuid_str);
+		if (ret < 0)
+			ret = uuid_from_systemd(uuid_str);
+	}
 #ifdef LIBUUID
 	if (ret < 0) {
 		uuid_generate_random(uuid);
-- 
2.31.1