[iproute2,V3,1/4] rdma: Add basic infrastructure for RDMA tool

diff --git a/Makefile b/Makefile
index 18de7dcb..c255063b 100644
--- a/Makefile
+++ b/Makefile
@@ -52,7 +52,7 @@  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 += $(LIBNETLINK)
diff --git a/rdma/.gitignore b/rdma/.gitignore
new file mode 100644
index 00000000..51fb172b
--- /dev/null
+++ b/rdma/.gitignore
@@ -0,0 +1 @@ 
+rdma
diff --git a/rdma/Makefile b/rdma/Makefile
new file mode 100644
index 00000000..64da2142
--- /dev/null
+++ b/rdma/Makefile
@@ -0,0 +1,22 @@ 
+include ../Config
+
+ifeq ($(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)
diff --git a/rdma/rdma.c b/rdma/rdma.c
new file mode 100644
index 00000000..29273839
--- /dev/null
+++ b/rdma/rdma.c
@@ -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 <limits.h>
+#include <rdma/rdma_netlink.h>
+
+#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 rdma *rd)
+{
+	help(rd->filename);
+	return 0;
+}
+
+static int rd_cmd(struct rdma *rd)
+{
+	const struct rdma_cmd cmds[] = {
+		{ NULL,		cmd_help },
+		{ "help",	cmd_help },
+		{ 0 }
+	};
+
+	return rdma_exec_cmd(rd, cmds, "object");
+}
+
+static int rd_init(struct rdma *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;
+
+	rdma_prepare_msg(rd, RDMA_NLDEV_CMD_GET, &seq, (NLM_F_REQUEST | NLM_F_ACK | NLM_F_DUMP));
+	if ((ret = rdma_send_msg(rd)))
+		return ret;
+
+	return rdma_recv_msg(rd, rd_dev_init_cb, rd, seq);
+}
+
+static void rd_free(struct rdma *rd)
+{
+	free(rd->buff);
+	rdma_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 rdma 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;
+}
diff --git a/rdma/rdma.h b/rdma/rdma.h
new file mode 100644
index 00000000..0c01b091
--- /dev/null
+++ b/rdma/rdma.h
@@ -0,0 +1,70 @@ 
+/*
+ * 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 "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 rdma {
+	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 rdma_cmd {
+	const char *cmd;
+	int (*func)(struct rdma *rd);
+};
+
+/*
+ * Parser interface
+ */
+bool rd_no_arg(struct rdma *rd);
+void rd_arg_inc(struct rdma *rd);
+
+int rdma_exec_cmd(struct rdma *rd, const struct rdma_cmd *c, const char *str);
+
+/*
+ * Device manipulation
+ */
+void rdma_free_devmap(struct rdma *rd);
+
+/*
+ * Netlink
+ */
+int rdma_send_msg(struct rdma *rd);
+int rdma_recv_msg(struct rdma *rd, mnl_cb_t callback, void *data, uint32_t seq);
+void rdma_prepare_msg(struct rdma *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_ */
diff --git a/rdma/utils.c b/rdma/utils.c
new file mode 100644
index 00000000..b554eff7
--- /dev/null
+++ b/rdma/utils.c
@@ -0,0 +1,223 @@ 
+/*
+ * 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 <sys/types.h>
+#include <dirent.h>
+#include <time.h>
+
+#include "rdma.h"
+#include <rdma/rdma_netlink.h>
+
+static int rd_argc(struct rdma *rd)
+{
+	return rd->argc;
+}
+
+static char *rd_argv(struct rdma *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 rdma *rd, const char *pattern)
+{
+	if (!rd_argc(rd))
+		return false;
+	return strcmpx(rd_argv(rd), pattern) == 0;
+}
+
+void rd_arg_inc(struct rdma *rd)
+{
+	if (!rd_argc(rd))
+		return;
+	rd->argc--;
+	rd->argv++;
+}
+
+bool rd_no_arg(struct rdma *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 rdma *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 rdma *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 rdma_free_devmap(struct rdma *rd)
+{
+	if(!rd)
+		return;
+	dev_map_cleanup(rd);
+}
+
+int rdma_exec_cmd(struct rdma *rd, const struct rdma_cmd *cmds, const char *str)
+{
+	const struct rdma_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 rdma_prepare_msg(struct rdma *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 rdma_send_msg(struct rdma *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 rdma_recv_msg(struct rdma *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;
+}