[PATCH v4 iproute2 0/7] RDMAtool

@@ -2,7 +2,7 @@ include ../Config
 
 ifeq ($(HAVE_MNL),y)
 
-RDMA_OBJ = rdma.o utils.o dev.o
+RDMA_OBJ = rdma.o utils.o dev.o link.o
 
 TARGETS=rdma
 CFLAGS += $(shell $(PKG_CONFIG) libmnl --cflags)

@@ -0,0 +1,274 @@
+/*
+ * link.c	RDMA tool
+ *
+ *              This program is free software; you can redistribute it and/or
+ *              modify it under the terms of the GNU General Public License
+ *              as published by the Free Software Foundation; either version
+ *              2 of the License, or (at your option) any later version.
+ *
+ * Authors:     Leon Romanovsky <leonro@mellanox.com>
+ */
+
+#include "rdma.h"
+
+static int link_help(struct rd *rd)
+{
+	pr_out("Usage: %s link show [DEV/PORT_INDEX]\n", rd->filename);
+	return 0;
+}
+
+static const char *caps_to_str(uint32_t idx)
+{
+	uint64_t cap = 1 << idx;
+
+	switch (cap) {
+	case RDMA_PORT_SM: return "SM";
+	case RDMA_PORT_NOTICE: return "NOTICE";
+	case RDMA_PORT_TRAP: return "TRAP";
+	case RDMA_PORT_OPT_IPD: return "OPT_IPD";
+	case RDMA_PORT_AUTO_MIGR: return "AUTO_MIG";
+	case RDMA_PORT_SL_MAP: return "SL_MAP";
+	case RDMA_PORT_MKEY_NVRAM: return "MKEY_NVRAM";
+	case RDMA_PORT_PKEY_NVRAM: return "PKEY_NVRAM";
+	case RDMA_PORT_LED_INFO: return "LED_INFO";
+	case RDMA_PORT_SM_DISABLED: return "SM_DISABLED";
+	case RDMA_PORT_SYS_IMAGE_GUID: return "SYS_IMAGE_GUID";
+	case RDMA_PORT_PKEY_SW_EXT_PORT_TRAP: return "PKEY_SW_EXT_PORT_TRAP";
+	case RDMA_PORT_EXTENDED_SPEEDS: return "EXTENDED_SPEEDS";
+	case RDMA_PORT_CM: return "CM";
+	case RDMA_PORT_SNMP_TUNNEL: return "SNMP_TUNNEL";
+	case RDMA_PORT_REINIT: return "REINIT";
+	case RDMA_PORT_DEVICE_MGMT: return "DEVICE_MGMT";
+	case RDMA_PORT_VENDOR_CLASS: return "VENDOR_CLASS";
+	case RDMA_PORT_DR_NOTICE: return "PORT_DR_NOTICE";
+	case RDMA_PORT_CAP_MASK_NOTICE: return "CAP_MASK_NOTICE";
+	case RDMA_PORT_BOOT_MGMT: return "BOOT_MGMT";
+	case RDMA_PORT_LINK_LATENCY: return "LINK_LATENCY";
+	case RDMA_PORT_CLIENT_REG: return "CLIENT_REG";
+	case RDMA_PORT_IP_BASED_GIDS: return "IP_BASED_GIDS";
+	default: return "UKNOWN";
+	}
+};
+
+static void link_print_caps(struct nlattr **tb)
+{
+	uint64_t caps;
+	uint32_t idx;
+
+	if (!tb[RDMA_NLDEV_ATTR_CAP_FLAGS])
+		return;
+
+	caps = mnl_attr_get_u64(tb[RDMA_NLDEV_ATTR_CAP_FLAGS]);
+
+	pr_out("\n    caps: <");
+	for (idx = 0; caps; idx++) {
+		if (caps & 0x1) {
+			pr_out("%s", caps_to_str(idx));
+			if (caps >> 0x1)
+				pr_out(", ");
+		}
+		caps >>= 0x1;
+	}
+
+	pr_out(">");
+}
+
+static void link_print_subnet_prefix(struct nlattr **tb)
+{
+	uint64_t subnet_prefix;
+
+	if (!tb[RDMA_NLDEV_ATTR_SUBNET_PREFIX])
+		return;
+
+	subnet_prefix = mnl_attr_get_u64(tb[RDMA_NLDEV_ATTR_SUBNET_PREFIX]);
+	rd_print_u64("subnet_prefix", subnet_prefix);
+}
+
+static void link_print_lid(struct nlattr **tb)
+{
+	if (!tb[RDMA_NLDEV_ATTR_LID])
+		return;
+
+	pr_out("lid %u ",
+	       mnl_attr_get_u32(tb[RDMA_NLDEV_ATTR_LID]));
+}
+
+static void link_print_sm_lid(struct nlattr **tb)
+{
+	if (!tb[RDMA_NLDEV_ATTR_SM_LID])
+		return;
+
+	pr_out("sm_lid %u ",
+	       mnl_attr_get_u32(tb[RDMA_NLDEV_ATTR_SM_LID]));
+}
+
+static void link_print_lmc(struct nlattr **tb)
+{
+	if (!tb[RDMA_NLDEV_ATTR_LMC])
+		return;
+
+	pr_out("lmc %u ", mnl_attr_get_u8(tb[RDMA_NLDEV_ATTR_LMC]));
+}
+
+static const char *link_state_to_str(uint8_t link_state)
+{
+	switch (link_state) {
+	case RDMA_LINK_STATE_NOP: return "NOP";
+	case RDMA_LINK_STATE_DOWN: return "DOWN";
+	case RDMA_LINK_STATE_INIT: return "INIT";
+	case RDMA_LINK_STATE_ARMED: return "ARMED";
+	case RDMA_LINK_STATE_ACTIVE: return "ACTIVE";
+	case RDMA_LINK_STATE_ACTIVE_DEFER: return "ACTIVE_DEFER";
+	default: return "UKNOWN";
+	}
+};
+
+static void link_print_state(struct nlattr **tb)
+{
+	uint8_t state;
+
+	if (!tb[RDMA_NLDEV_ATTR_PORT_STATE])
+		return;
+
+	state = mnl_attr_get_u8(tb[RDMA_NLDEV_ATTR_PORT_STATE]);
+	pr_out("state %s ", link_state_to_str(state));
+}
+
+static const char *phys_state_to_str(uint8_t phys_state)
+{
+	switch (phys_state) {
+	case RDMA_LINK_PHYS_STATE_SLEEP: return "SLEEP";
+	case RDMA_LINK_PHYS_STATE_POLLING: return "POLLING";
+	case RDMA_LINK_PHYS_STATE_DISABLED: return "DISABLED";
+	case RDMA_LINK_PHYS_STATE_PORT_CONFIGURATION_TRAINING: return "ARMED";
+	case RDMA_LINK_PHYS_STATE_LINK_UP: return "LINK_UP";
+	case RDMA_LINK_PHYS_STATE_LINK_ERROR_RECOVER:
+						return "LINK_ERROR_RECOVER";
+	case RDMA_LINK_PHYS_STATE_LINK_PHY_TEST: return "PHY_TEST";
+	default: return "UKNOWN";
+	}
+};
+
+static void link_print_phys_state(struct nlattr **tb)
+{
+	uint8_t phys_state;
+
+	if (!tb[RDMA_NLDEV_ATTR_PORT_PHYS_STATE])
+		return;
+
+	phys_state = mnl_attr_get_u8(tb[RDMA_NLDEV_ATTR_PORT_PHYS_STATE]);
+	pr_out("physical_state %s ", phys_state_to_str(phys_state));
+}
+
+static int link_parse_cb(const struct nlmsghdr *nlh, void *data)
+{
+	struct nlattr *tb[RDMA_NLDEV_ATTR_MAX] = {};
+	struct rd *rd = data;
+
+	mnl_attr_parse(nlh, 0, rd_attr_cb, tb);
+	if (!tb[RDMA_NLDEV_ATTR_DEV_INDEX] || !tb[RDMA_NLDEV_ATTR_DEV_NAME])
+		return MNL_CB_ERROR;
+
+	if (!tb[RDMA_NLDEV_ATTR_PORT_INDEX]) {
+		pr_err("This tool doesn't support switches yet\n");
+		return MNL_CB_ERROR;
+	}
+
+	pr_out("%u/%u: %s/%u: ",
+	       mnl_attr_get_u32(tb[RDMA_NLDEV_ATTR_DEV_INDEX]),
+	       mnl_attr_get_u32(tb[RDMA_NLDEV_ATTR_PORT_INDEX]),
+	       mnl_attr_get_str(tb[RDMA_NLDEV_ATTR_DEV_NAME]),
+	       mnl_attr_get_u32(tb[RDMA_NLDEV_ATTR_PORT_INDEX]));
+	link_print_subnet_prefix(tb);
+	link_print_lid(tb);
+	link_print_sm_lid(tb);
+	link_print_lmc(tb);
+	link_print_state(tb);
+	link_print_phys_state(tb);
+	if (rd->show_details)
+		link_print_caps(tb);
+
+	pr_out("\n");
+	return MNL_CB_OK;
+}
+
+static int link_no_args(struct rd *rd)
+{
+	uint32_t seq;
+	int ret;
+
+	rd_prepare_msg(rd, RDMA_NLDEV_CMD_PORT_GET, &seq,
+		       (NLM_F_REQUEST | NLM_F_ACK));
+	mnl_attr_put_u32(rd->nlh, RDMA_NLDEV_ATTR_DEV_INDEX, rd->dev_idx);
+	mnl_attr_put_u32(rd->nlh, RDMA_NLDEV_ATTR_PORT_INDEX, rd->port_idx);
+	ret = rd_send_msg(rd);
+	if (ret)
+		return ret;
+
+	return rd_recv_msg(rd, link_parse_cb, rd, seq);
+}
+
+static int link_one_show(struct rd *rd)
+{
+	const struct rd_cmd cmds[] = {
+		{ NULL,		link_no_args},
+		{ 0 }
+	};
+
+	return rd_exec_cmd(rd, cmds, "parameter");
+}
+
+static int link_show(struct rd *rd)
+{
+	struct dev_map *dev_map;
+	uint32_t port;
+	int ret;
+
+	if (rd_no_arg(rd)) {
+		list_for_each_entry(dev_map, &rd->dev_map_list, list) {
+			rd->dev_idx = dev_map->idx;
+			for (port = 1; port < dev_map->num_ports + 1; port++) {
+				rd->port_idx = port;
+				ret = link_one_show(rd);
+				if (ret)
+					return ret;
+			}
+		}
+
+	} else {
+		dev_map = dev_map_lookup(rd, true);
+		port = get_port_from_argv(rd);
+		if (!dev_map || port > dev_map->num_ports) {
+			pr_err("Wrong device name\n");
+			return -ENOENT;
+		}
+		rd_arg_inc(rd);
+		rd->dev_idx = dev_map->idx;
+		rd->port_idx = port ? : 1;
+		for (; rd->port_idx < dev_map->num_ports + 1; rd->port_idx++) {
+			ret = link_one_show(rd);
+			if (ret)
+				return ret;
+			if (port)
+				/*
+				 * We got request to show link for devname
+				 * with port index.
+				 */
+				break;
+		}
+	}
+	return 0;
+}
+
+int cmd_link(struct rd *rd)
+{
+	const struct rd_cmd cmds[] = {
+		{ NULL,		link_show },
+		{ "show",	link_show },
+		{ "list",	link_show },
+		{ "help",	link_help },
+		{ 0 }
+	};
+
+	return rd_exec_cmd(rd, cmds, "link command");
+}

@@ -15,7 +15,7 @@
 static void help(char *name)
 {
 	pr_out("Usage: %s [ OPTIONS ] OBJECT { COMMAND | help }\n"
-	       "where  OBJECT := { dev | help }\n"
+	       "where  OBJECT := { dev | link | help }\n"
 	       "       OPTIONS := { -V[ersion] | -d[etails]}\n", name);
 }
 

@@ -31,6 +31,7 @@ static int rd_cmd(struct rd *rd)
 		{ NULL,		cmd_help },
 		{ "help",	cmd_help },
 		{ "dev",	cmd_dev },
+		{ "link",	cmd_link },
 		{ 0 }
 	};
 

@@ -107,6 +107,11 @@ static const enum mnl_attr_data_type nldev_policy[RDMA_NLDEV_ATTR_MAX] = {
 	[RDMA_NLDEV_ATTR_FW_VERSION] = MNL_TYPE_NUL_STRING,
 	[RDMA_NLDEV_ATTR_NODE_GUID] = MNL_TYPE_U64,
 	[RDMA_NLDEV_ATTR_SYS_IMAGE_GUID] = MNL_TYPE_U64,
+	[RDMA_NLDEV_ATTR_LID] = MNL_TYPE_U32,
+	[RDMA_NLDEV_ATTR_SM_LID] = MNL_TYPE_U32,
+	[RDMA_NLDEV_ATTR_LMC] = MNL_TYPE_U8,
+	[RDMA_NLDEV_ATTR_PORT_STATE] = MNL_TYPE_U8,
+	[RDMA_NLDEV_ATTR_PORT_PHYS_STATE] = MNL_TYPE_U8,
 	[RDMA_NLDEV_ATTR_DEV_NODE_TYPE] = MNL_TYPE_U8,
 };
 

@@ -49,7 +49,7 @@ WFLAGS += -Wmissing-declarations -Wold-style-definition -Wformat=2
 CFLAGS := $(WFLAGS) $(CCOPTS) -I../include $(DEFINES) $(CFLAGS)
 YACCFLAGS = -d -t -v
 
-SUBDIRS=lib ip tc bridge misc netem genl tipc devlink man
+SUBDIRS=lib ip tc bridge misc netem genl tipc devlink rdma man
 
 LIBNETLINK=../lib/libnetlink.a ../lib/libutil.a
 LDLIBS += $(LIBNETLINK)

@@ -0,0 +1 @@
+rdma

@@ -0,0 +1,22 @@
+include ../Config
+
+ifeq ($(HAVE_MNL),y)
+
+RDMA_OBJ = rdma.o utils.o
+
+TARGETS=rdma
+CFLAGS += $(shell $(PKG_CONFIG) libmnl --cflags)
+LDLIBS += $(shell $(PKG_CONFIG) libmnl --libs)
+
+endif
+
+all:	$(TARGETS) $(LIBS)
+
+rdma:	$(RDMA_OBJ) $(LIBS)
+	$(QUIET_LINK)$(CC) $^ $(LDFLAGS) $(LDLIBS) -o $@
+
+install: all
+	install -m 0755 $(TARGETS) $(DESTDIR)$(SBINDIR)
+
+clean:
+	rm -f $(RDMA_OBJ) $(TARGETS)

@@ -0,0 +1,116 @@
+/*
+ * rdma.c	RDMA tool
+ *
+ *              This program is free software; you can redistribute it and/or
+ *              modify it under the terms of the GNU General Public License
+ *              as published by the Free Software Foundation; either version
+ *              2 of the License, or (at your option) any later version.
+ *
+ * Authors:     Leon Romanovsky <leonro@mellanox.com>
+ */
+
+#include "rdma.h"
+#include "SNAPSHOT.h"
+
+static void help(char *name)
+{
+	pr_out("Usage: %s [ OPTIONS ] OBJECT { COMMAND | help }\n"
+	       "where  OBJECT := { help }\n"
+	       "       OPTIONS := { -V[ersion] | -d[etails]}\n", name);
+}
+
+static int cmd_help(struct rd *rd)
+{
+	help(rd->filename);
+	return 0;
+}
+
+static int rd_cmd(struct rd *rd)
+{
+	const struct rd_cmd cmds[] = {
+		{ NULL,		cmd_help },
+		{ "help",	cmd_help },
+		{ 0 }
+	};
+
+	return rd_exec_cmd(rd, cmds, "object");
+}
+
+static int rd_init(struct rd *rd, int argc, char **argv, char *filename)
+{
+	uint32_t seq;
+	int ret;
+
+	rd->filename = filename;
+	rd->argc = argc;
+	rd->argv = argv;
+	INIT_LIST_HEAD(&rd->dev_map_list);
+	rd->buff = malloc(MNL_SOCKET_BUFFER_SIZE);
+	if (!rd->buff)
+		return -ENOMEM;
+
+	rd_prepare_msg(rd, RDMA_NLDEV_CMD_GET,
+		       &seq, (NLM_F_REQUEST | NLM_F_ACK | NLM_F_DUMP));
+	ret = rd_send_msg(rd);
+	if (ret)
+		return ret;
+
+	return rd_recv_msg(rd, rd_dev_init_cb, rd, seq);
+}
+
+static void rd_free(struct rd *rd)
+{
+	free(rd->buff);
+	rd_free_devmap(rd);
+}
+
+int main(int argc, char **argv)
+{
+	static const struct option long_options[] = {
+		{ "version",		no_argument,		NULL, 'V' },
+		{ "help",		no_argument,		NULL, 'h' },
+		{ "details",		no_argument,		NULL, 'd' },
+		{ NULL, 0, NULL, 0 }
+	};
+	bool show_details = false;
+	char *filename;
+	struct rd rd;
+	int opt;
+	int err;
+
+	filename = basename(argv[0]);
+
+	while ((opt = getopt_long(argc, argv, "Vhd",
+				  long_options, NULL)) >= 0) {
+		switch (opt) {
+		case 'V':
+			printf("%s utility, iproute2-ss%s\n",
+			       filename, SNAPSHOT);
+			return EXIT_SUCCESS;
+		case 'd':
+			show_details = true;
+			break;
+		case 'h':
+			help(filename);
+			return EXIT_SUCCESS;
+		default:
+			pr_err("Unknown option.\n");
+			help(filename);
+			return EXIT_FAILURE;
+		}
+	}
+
+	argc -= optind;
+	argv += optind;
+
+	err = rd_init(&rd, argc, argv, filename);
+	if (err)
+		goto out;
+
+	rd.show_details = show_details;
+	err = rd_cmd(&rd);
+out:
+	/* Always cleanup */
+	rd_free(&rd);
+	return err ? EXIT_FAILURE : EXIT_SUCCESS;
+}

@@ -0,0 +1,74 @@
+/*
+ * rdma.c	RDMA tool
+ *
+ *              This program is free software; you can redistribute it and/or
+ *              modify it under the terms of the GNU General Public License
+ *              as published by the Free Software Foundation; either version
+ *              2 of the License, or (at your option) any later version.
+ *
+ * Authors:     Leon Romanovsky <leonro@mellanox.com>
+ */
+#ifndef _RDMA_TOOL_H_
+#define _RDMA_TOOL_H_
+
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <getopt.h>
+#include <libmnl/libmnl.h>
+#include <rdma/rdma_netlink.h>
+#include <time.h>
+#include <rdma/ib_user_verbs.h>
+#include <rdma/rdma_netlink.h>
+#include <rdma/rdma.h>
+
+#include "list.h"
+
+#define pr_err(args...) fprintf(stderr, ##args)
+#define pr_out(args...) fprintf(stdout, ##args)
+
+struct dev_map {
+	struct list_head list;
+	char *dev_name;
+	uint32_t num_ports;
+	uint32_t idx;
+};
+
+struct rd {
+	int argc;
+	char **argv;
+	char *filename;
+	bool show_details;
+	struct list_head dev_map_list;
+	struct mnl_socket *nl;
+	struct nlmsghdr *nlh;
+	char *buff;
+};
+
+struct rd_cmd {
+	const char *cmd;
+	int (*func)(struct rd *rd);
+};
+
+/*
+ * Parser interface
+ */
+bool rd_no_arg(struct rd *rd);
+void rd_arg_inc(struct rd *rd);
+
+int rd_exec_cmd(struct rd *rd, const struct rd_cmd *c, const char *str);
+
+/*
+ * Device manipulation
+ */
+void rd_free_devmap(struct rd *rd);
+
+/*
+ * Netlink
+ */
+int rd_send_msg(struct rd *rd);
+int rd_recv_msg(struct rd *rd, mnl_cb_t callback, void *data, uint32_t seq);
+void rd_prepare_msg(struct rd *rd, uint32_t cmd, uint32_t *seq, uint16_t flags);
+int rd_dev_init_cb(const struct nlmsghdr *nlh, void *data);
+int rd_attr_cb(const struct nlattr *attr, void *data);
+#endif /* _RDMA_TOOL_H_ */

@@ -0,0 +1,217 @@
+/*
+ * utils.c	RDMA tool
+ *
+ *              This program is free software; you can redistribute it and/or
+ *              modify it under the terms of the GNU General Public License
+ *              as published by the Free Software Foundation; either version
+ *              2 of the License, or (at your option) any later version.
+ *
+ * Authors:     Leon Romanovsky <leonro@mellanox.com>
+ */
+
+#include "rdma.h"
+
+static int rd_argc(struct rd *rd)
+{
+	return rd->argc;
+}
+
+static char *rd_argv(struct rd *rd)
+{
+	if (!rd_argc(rd))
+		return NULL;
+	return *rd->argv;
+}
+
+static int strcmpx(const char *str1, const char *str2)
+{
+	if (strlen(str1) > strlen(str2))
+		return -1;
+	return strncmp(str1, str2, strlen(str1));
+}
+
+static bool rd_argv_match(struct rd *rd, const char *pattern)
+{
+	if (!rd_argc(rd))
+		return false;
+	return strcmpx(rd_argv(rd), pattern) == 0;
+}
+
+void rd_arg_inc(struct rd *rd)
+{
+	if (!rd_argc(rd))
+		return;
+	rd->argc--;
+	rd->argv++;
+}
+
+bool rd_no_arg(struct rd *rd)
+{
+	return rd_argc(rd) == 0;
+}
+
+static struct dev_map *dev_map_alloc(const char *dev_name)
+{
+	struct dev_map *dev_map;
+
+	dev_map = calloc(1, sizeof(*dev_map));
+	if (!dev_map)
+		return NULL;
+	dev_map->dev_name = strdup(dev_name);
+
+	return dev_map;
+}
+
+static void dev_map_free(struct dev_map *dev_map)
+{
+	if (!dev_map)
+		return;
+
+	free(dev_map->dev_name);
+	free(dev_map);
+}
+
+static void dev_map_cleanup(struct rd *rd)
+{
+	struct dev_map *dev_map, *tmp;
+
+	list_for_each_entry_safe(dev_map, tmp,
+				 &rd->dev_map_list, list) {
+		list_del(&dev_map->list);
+		dev_map_free(dev_map);
+	}
+}
+
+static const enum mnl_attr_data_type nldev_policy[RDMA_NLDEV_ATTR_MAX] = {
+	[RDMA_NLDEV_ATTR_DEV_NAME] = MNL_TYPE_NUL_STRING,
+	[RDMA_NLDEV_ATTR_PORT_INDEX] = MNL_TYPE_U32,
+};
+
+int rd_attr_cb(const struct nlattr *attr, void *data)
+{
+	const struct nlattr **tb = data;
+	int type;
+
+	if (mnl_attr_type_valid(attr, RDMA_NLDEV_ATTR_MAX) < 0)
+		return MNL_CB_ERROR;
+
+	type = mnl_attr_get_type(attr);
+
+	if (mnl_attr_validate(attr, nldev_policy[type]) < 0)
+		return MNL_CB_ERROR;
+
+	tb[type] = attr;
+	return MNL_CB_OK;
+}
+
+int rd_dev_init_cb(const struct nlmsghdr *nlh, void *data)
+{
+	struct nlattr *tb[RDMA_NLDEV_ATTR_MAX] = {};
+	struct dev_map *dev_map;
+	struct rd *rd = data;
+	const char *dev_name;
+
+	mnl_attr_parse(nlh, 0, rd_attr_cb, tb);
+	if (!tb[RDMA_NLDEV_ATTR_DEV_NAME] || !tb[RDMA_NLDEV_ATTR_DEV_INDEX])
+		return MNL_CB_ERROR;
+	if (!tb[RDMA_NLDEV_ATTR_PORT_INDEX]) {
+		pr_err("This tool doesn't support switches yet\n");
+		return MNL_CB_ERROR;
+	}
+
+	dev_name = mnl_attr_get_str(tb[RDMA_NLDEV_ATTR_DEV_NAME]);
+
+	dev_map = dev_map_alloc(dev_name);
+	if (!dev_map)
+		/* The main function will cleanup the allocations */
+		return MNL_CB_ERROR;
+	list_add_tail(&dev_map->list, &rd->dev_map_list);
+
+	dev_map->num_ports = mnl_attr_get_u32(tb[RDMA_NLDEV_ATTR_PORT_INDEX]);
+	dev_map->idx = mnl_attr_get_u32(tb[RDMA_NLDEV_ATTR_DEV_INDEX]);
+	return MNL_CB_OK;
+}
+
+void rd_free_devmap(struct rd *rd)
+{
+	if (!rd)
+		return;
+	dev_map_cleanup(rd);
+}
+
+int rd_exec_cmd(struct rd *rd, const struct rd_cmd *cmds, const char *str)
+{
+	const struct rd_cmd *c;
+
+	/* First argument in objs table is default variant */
+	if (rd_no_arg(rd))
+		return cmds->func(rd);
+
+	for (c = cmds + 1; c->cmd; ++c) {
+		if (rd_argv_match(rd, c->cmd)) {
+			/* Move to next argument */
+			rd_arg_inc(rd);
+			return c->func(rd);
+		}
+	}
+
+	pr_err("Unknown %s '%s'.\n", str, rd_argv(rd));
+	return 0;
+}
+
+void rd_prepare_msg(struct rd *rd, uint32_t cmd, uint32_t *seq, uint16_t flags)
+{
+	*seq = time(NULL);
+
+	rd->nlh = mnl_nlmsg_put_header(rd->buff);
+	rd->nlh->nlmsg_type = RDMA_NL_GET_TYPE(RDMA_NL_NLDEV, cmd);
+	rd->nlh->nlmsg_seq = *seq;
+	rd->nlh->nlmsg_flags = flags;
+}
+
+int rd_send_msg(struct rd *rd)
+{
+	int ret;
+
+	rd->nl = mnl_socket_open(NETLINK_RDMA);
+	if (!rd->nl) {
+		pr_err("Failed to open NETLINK_RDMA socket\n");
+		return -ENODEV;
+	}
+
+	ret = mnl_socket_bind(rd->nl, 0, MNL_SOCKET_AUTOPID);
+	if (ret < 0) {
+		pr_err("Failed to bind socket with err %d\n", ret);
+		goto err;
+	}
+
+	ret = mnl_socket_sendto(rd->nl, rd->nlh, rd->nlh->nlmsg_len);
+	if (ret < 0) {
+		pr_err("Failed to send to socket with err %d\n", ret);
+		goto err;
+	}
+	return 0;
+
+err:
+	mnl_socket_close(rd->nl);
+	return ret;
+}
+
+int rd_recv_msg(struct rd *rd, mnl_cb_t callback, void *data, unsigned int seq)
+{
+	int ret;
+	unsigned int portid;
+	char buf[MNL_SOCKET_BUFFER_SIZE];
+
+	portid = mnl_socket_get_portid(rd->nl);
+	do {
+		ret = mnl_socket_recvfrom(rd->nl, buf, sizeof(buf));
+		if (ret <= 0)
+			break;
+
+		ret = mnl_cb_run(buf, ret, seq, portid, callback, data);
+	} while (ret > 0);
+
+	mnl_socket_close(rd->nl);
+	return ret;
+}

@@ -16,7 +16,7 @@ static void help(char *name)
 {
 	pr_out("Usage: %s [ OPTIONS ] OBJECT { COMMAND | help }\n"
 	       "where  OBJECT := { dev | link | help }\n"
-	       "       OPTIONS := { -V[ersion] | -d[etails]}\n", name);
+	       "       OPTIONS := { -V[ersion] | -d[etails] | -j[son] | -p[retty]}\n", name);
 }
 
 static int cmd_help(struct rd *rd)

@@ -47,6 +47,16 @@ static int rd_init(struct rd *rd, int argc, char **argv, char *filename)
 	rd->argc = argc;
 	rd->argv = argv;
 	INIT_LIST_HEAD(&rd->dev_map_list);
+
+	if (rd->json_output) {
+		rd->jw = jsonw_new(stdout);
+		if (!rd->jw) {
+			pr_err("Failed to create JSON writer\n");
+			return -ENOMEM;
+		}
+		jsonw_pretty(rd->jw, rd->pretty_output);
+	}
+
 	rd->buff = malloc(MNL_SOCKET_BUFFER_SIZE);
 	if (!rd->buff)
 		return -ENOMEM;

@@ -62,6 +72,8 @@ static int rd_init(struct rd *rd, int argc, char **argv, char *filename)
 
 static void rd_free(struct rd *rd)
 {
+	if (rd->json_output)
+		jsonw_destroy(&rd->jw);
 	free(rd->buff);
 	rd_free_devmap(rd);
 }

@@ -71,10 +83,14 @@ int main(int argc, char **argv)
 	static const struct option long_options[] = {
 		{ "version",		no_argument,		NULL, 'V' },
 		{ "help",		no_argument,		NULL, 'h' },
+		{ "json",		no_argument,		NULL, 'j' },
+		{ "pretty",		no_argument,		NULL, 'p' },
 		{ "details",		no_argument,		NULL, 'd' },
 		{ NULL, 0, NULL, 0 }
 	};
+	bool pretty_output = false;
 	bool show_details = false;
+	bool json_output = false;
 	char *filename;
 	struct rd rd;
 	int opt;

@@ -82,16 +98,22 @@ int main(int argc, char **argv)
 
 	filename = basename(argv[0]);
 
-	while ((opt = getopt_long(argc, argv, "Vhd",
+	while ((opt = getopt_long(argc, argv, "Vhdpj",
 				  long_options, NULL)) >= 0) {
 		switch (opt) {
 		case 'V':
 			printf("%s utility, iproute2-ss%s\n",
 			       filename, SNAPSHOT);
 			return EXIT_SUCCESS;
+		case 'p':
+			pretty_output = true;
+			break;
 		case 'd':
 			show_details = true;
 			break;
+		case 'j':
+			json_output = true;
+			break;
 		case 'h':
 			help(filename);
 			return EXIT_SUCCESS;

@@ -105,11 +127,14 @@ int main(int argc, char **argv)
 	argc -= optind;
 	argv += optind;
 
+	rd.show_details = show_details;
+	rd.json_output = json_output;
+	rd.pretty_output = pretty_output;
+
 	err = rd_init(&rd, argc, argv, filename);
 	if (err)
 		goto out;
 
-	rd.show_details = show_details;
 	err = rd_cmd(&rd);
 out:
 	/* Always cleanup */

@@ -23,6 +23,7 @@
 #include <rdma/rdma.h>
 
 #include "list.h"
+#include "json_writer.h"
 
 #define pr_err(args...) fprintf(stderr, ##args)
 #define pr_out(args...) fprintf(stdout, ##args)

@@ -45,6 +46,9 @@ struct rd {
 	struct mnl_socket *nl;
 	struct nlmsghdr *nlh;
 	char *buff;
+	json_writer_t *jw;
+	bool json_output;
+	bool pretty_output;
 };
 
 struct rd_cmd {

@@ -61,7 +61,7 @@ static const char *dev_caps_to_str(uint32_t idx)
 	}
 }
 
-static void dev_print_caps(struct nlattr **tb)
+static void dev_print_caps(struct rd *rd, struct nlattr **tb)
 {
 	uint64_t caps;
 	uint32_t idx;

@@ -71,48 +71,78 @@ static void dev_print_caps(struct nlattr **tb)
 
 	caps = mnl_attr_get_u64(tb[RDMA_NLDEV_ATTR_CAP_FLAGS]);
 
-	pr_out("\n    caps: <");
+	if (rd->json_output) {
+		jsonw_name(rd->jw, "caps");
+		jsonw_start_array(rd->jw);
+	} else {
+		pr_out("\n    caps: <");
+	}
 	for (idx = 0; caps; idx++) {
 		if (caps & 0x1) {
-			pr_out("%s", dev_caps_to_str(idx));
-			if (caps >> 0x1)
-				pr_out(", ");
+			if (rd->json_output) {
+				jsonw_string(rd->jw, dev_caps_to_str(idx));
+			} else {
+				pr_out("%s", dev_caps_to_str(idx));
+				if (caps >> 0x1)
+					pr_out(", ");
+			}
 		}
 		caps >>= 0x1;
 	}
 
-	pr_out(">");
+	if (rd->json_output)
+		jsonw_end_array(rd->jw);
+	else
+		pr_out(">");
 }
 
-static void dev_print_fw(struct nlattr **tb)
+static void dev_print_fw(struct rd *rd, struct nlattr **tb)
 {
+	const char *str;
 	if (!tb[RDMA_NLDEV_ATTR_FW_VERSION])
 		return;
 
-	pr_out("fw %s ",
-	       mnl_attr_get_str(tb[RDMA_NLDEV_ATTR_FW_VERSION]));
+	str = mnl_attr_get_str(tb[RDMA_NLDEV_ATTR_FW_VERSION]);
+	if (rd->json_output)
+		jsonw_string_field(rd->jw, "fw", str);
+	else
+		pr_out("fw %s ", str);
 }
 
-static void dev_print_node_guid(struct nlattr **tb)
+static void dev_print_node_guid(struct rd *rd, struct nlattr **tb)
 {
 	uint64_t node_guid;
+	uint16_t vp[4];
+	char str[32];
 
 	if (!tb[RDMA_NLDEV_ATTR_NODE_GUID])
 		return;
 
 	node_guid = mnl_attr_get_u64(tb[RDMA_NLDEV_ATTR_NODE_GUID]);
-	rd_print_u64("node_guid", node_guid);
+	memcpy(vp, &node_guid, sizeof(uint64_t));
+	snprintf(str, 32, "%04x:%04x:%04x:%04x", vp[3], vp[2], vp[1], vp[0]);
+	if (rd->json_output)
+		jsonw_string_field(rd->jw, "node_guid", str);
+	else
+		pr_out("node_guid %s ", str);
 }
 
-static void dev_print_sys_image_guid(struct nlattr **tb)
+static void dev_print_sys_image_guid(struct rd *rd, struct nlattr **tb)
 {
 	uint64_t sys_image_guid;
+	uint16_t vp[4];
+	char str[32];
 
 	if (!tb[RDMA_NLDEV_ATTR_SYS_IMAGE_GUID])
 		return;
 
 	sys_image_guid = mnl_attr_get_u64(tb[RDMA_NLDEV_ATTR_SYS_IMAGE_GUID]);
-	rd_print_u64("sys_image_guid", sys_image_guid);
+	memcpy(vp, &sys_image_guid, sizeof(uint64_t));
+	snprintf(str, 32, "%04x:%04x:%04x:%04x", vp[3], vp[2], vp[1], vp[0]);
+	if (rd->json_output)
+		jsonw_string_field(rd->jw, "sys_image_guid", str);
+	else
+		pr_out("sys_image_guid %s ", str);
 }
 
 static const char *node_type_to_str(uint8_t node_type)