From fc8f7343feeb9928ae9ca4dca44e63afdb6499a9 Mon Sep 17 00:00:00 2001
From: Casey Tucker <dctucker@github.com>
Date: Wed, 2 Sep 2020 20:01:10 +0000
Subject: [PATCH] id-ctrl vs for Amazon Elastic Block Store

This allows the user to extract useful information from the
vendor-specific field when querying Elastic Block Storage
devices attached by Amazon Web Services. In particular, this
field is populated with the block device that was requested
by the user in the API call, which is of the form `/dev/sdc`
or `/dev/xvdc` rather than `/dev/nvme2`. This plugin reduces
the need for operating system maintainers to include vendor-
specific packages in their distribution.

https://docs.aws.amazon.com/AWSEC2/latest/UserGuide/nvme-ebs-volumes.html
https://github.com/aws/amazon-ec2-utils/blob/master/ebsnvme-id
---
 Makefile                 |  1 +
 plugins/amzn/amzn-nvme.c | 60 ++++++++++++++++++++++++++++++++++++++++
 plugins/amzn/amzn-nvme.h | 17 ++++++++++++
 3 files changed, 78 insertions(+)
 create mode 100644 plugins/amzn/amzn-nvme.c
 create mode 100644 plugins/amzn/amzn-nvme.h

diff --git a/Makefile b/Makefile
index f5e9853e..65afdbe0 100644
--- a/Makefile
+++ b/Makefile
@@ -66,6 +66,7 @@ UTIL_OBJS := util/argconfig.o util/suffix.o util/json.o util/parser.o
 
 PLUGIN_OBJS :=					\
 	plugins/intel/intel-nvme.o		\
+	plugins/amzn/amzn-nvme.o		\
 	plugins/lnvm/lnvm-nvme.o		\
 	plugins/memblaze/memblaze-nvme.o	\
 	plugins/wdc/wdc-nvme.o			\
diff --git a/plugins/amzn/amzn-nvme.c b/plugins/amzn/amzn-nvme.c
new file mode 100644
index 00000000..2a113c9d
--- /dev/null
+++ b/plugins/amzn/amzn-nvme.c
@@ -0,0 +1,60 @@
+#include <fcntl.h>
+#include <errno.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <unistd.h>
+#include <inttypes.h>
+
+#include "linux/nvme_ioctl.h"
+
+#include "common.h"
+#include "nvme.h"
+#include "nvme-print.h"
+#include "nvme-ioctl.h"
+#include "json.h"
+#include "plugin.h"
+
+#include "argconfig.h"
+#include "suffix.h"
+
+#define CREATE_CMD
+#include "amzn-nvme.h"
+
+struct nvme_vu_id_ctrl_field {
+	__u8			bdev[32];
+	__u8			reserved0[992];
+};
+
+static void json_amzn_id_ctrl(struct nvme_vu_id_ctrl_field *id,
+	char *bdev,
+	struct json_object *root)
+{
+	json_object_add_value_string(root, "bdev", bdev);
+}
+
+static void amzn_id_ctrl(__u8 *vs, struct json_object *root)
+{
+	struct nvme_vu_id_ctrl_field* id = (struct nvme_vu_id_ctrl_field *)vs;
+
+	char bdev[32] = { 0 };
+
+	int len = 0;
+	while (len < 31) {
+		if (id->bdev[++len] == ' ') {
+			break;
+		}
+	}
+	snprintf(bdev, len+1, "%s", id->bdev);
+
+	if (root) {
+		json_amzn_id_ctrl(id, bdev, root);
+		return;
+	}
+
+	printf("bdev      : %s\n", bdev);
+}
+
+static int id_ctrl(int argc, char **argv, struct command *cmd, struct plugin *plugin)
+{
+	return __id_ctrl(argc, argv, cmd, plugin, amzn_id_ctrl);
+}
diff --git a/plugins/amzn/amzn-nvme.h b/plugins/amzn/amzn-nvme.h
new file mode 100644
index 00000000..9b8d797c
--- /dev/null
+++ b/plugins/amzn/amzn-nvme.h
@@ -0,0 +1,17 @@
+#undef CMD_INC_FILE
+#define CMD_INC_FILE plugins/amzn/amzn-nvme
+
+#if !defined(AMZN_NVME) || defined(CMD_HEADER_MULTI_READ)
+#define AMZN_NVME
+
+#include "cmd.h"
+
+PLUGIN(NAME("amzn", "Amazon vendor specific extensions"),
+	COMMAND_LIST(
+		ENTRY("id-ctrl", "Send NVMe Identify Controller", id_ctrl)
+	)
+);
+
+#endif
+
+#include "define_cmd.h"
-- 
2.50.1