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Dynamic rdma link creation

PATCH Superseded Steve Wise 3 participants 12 messages Mar 26, 2019 – Apr 3, 2019

Subsystems (3)
Networking Network drivers InfiniBand

v2 of 3 Superseded Latest is v3 →

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Steve Wise

author
#0 lore raw

v2 cover Dynamic rdma link creation

This series adds rdmatool support for creating/deleting rdma links. This will be used, mainly, by soft rdma drivers to allow adding/deleting rdma links over netdev interfaces. It provides the user side for the following kernel changes merged in linux-5.1.

Changes since v1:

- move error receive checking from rd_sendrecv_msg() to rd_recv_msg().
- Add rd->suppress_errors to allow control over whether errors when reading a response should be ignored. Namely: resource queries can get errors like "none found" when querying for resources, and this error should not be displayed. So on a rd object basis, error suppression can be controlled.
- Rebased on rdma/for-next UABI (no need to sync rdma_netlink.h now)
- use chains of struct rd_cmd and rd_exec_cmd vs open coding the parsing for the 'link add' command.
- minor nit resolution
- added .mailmap file. If this is not desired for iproute2, then please drop the patch.

Changes since RFC:

- add rd_sendrecv_msg() and make use of it in dev_set as well as the new link commands.
- fixed problems with the man pages
- changed the command line to use "netdev" as the keyword for the network device, do avoid confused with the ib_device name.
- got rid of the "type" parameter for link delete. Also pass down the device index instead of the name, using the common rd services for validating the device name and fetching the index.

Thanks,

Steve.

----

Steve Wise (4):
Add .mailmap file
rdma: add helper rd_sendrecv_msg()
rdma: add 'link add/delete' commands
rdma: man page update for link add/delete

 .mailmap             |  8 +++++
 man/man8/rdma-link.8 | 47 +++++++++++++++++++++++++
 rdma/dev.c           |  2 +-
 rdma/link.c          | 83 ++++++++++++++++++++++++++++++++++++++++++++
 rdma/rdma.h          |  4 +++
 rdma/res.h           |  1 +
 rdma/utils.c         | 18 ++++++++++
 7 files changed, 162 insertions(+), 1 deletion(-)
 create mode 100644 .mailmap
Signature · 1 line
2.20.1
author
#1 lore raw

PATCH v2 1/4 Add .mailmap file

.mailmap allows tracking multiple email addresses to the proper user name.

Signed-off-by Steve Wise <[email protected]>
---
 .mailmap | 8 ++++++++
 1 file changed, 8 insertions(+)
 create mode 100644 .mailmap
.mailmap new file +8 -0
new file mode 100644
index 00000000..c012d3d0
@@ -0,0 +1,8 @@
+#
+# This list is used by git-shortlog to fix a few botched name translations
+# in the git archive, either because the author's full name was messed up
+# and/or not always written the same way, making contributions from the
+# same person appearing not to be so or badly displayed.
+#
+Steve Wise <[email protected]> <[email protected]>
+Steve Wise <[email protected]> <[email protected]>
Signature · 1 line
2.20.1
author
#3 lore raw

PATCH v2 2/4 rdma: add helper rd_sendrecv_msg()

In reply to Steve Wise

This function sends the constructed netlink message and then receives the response.

Change rd_recv_msg() to display any error messages.

Change 'rdma dev set' to use rd_sendrecv_msg().

Signed-off-by Steve Wise <[email protected]>
---
 rdma/dev.c   |  2 +-
 rdma/rdma.h  |  2 ++
 rdma/res.h   |  1 +
 rdma/utils.c | 18 ++++++++++++++++++
 4 files changed, 22 insertions(+), 1 deletion(-)
rdma/dev.c +1 -1
index 954e0015..33962520 100644
@@ -268,7 +268,7 @@ static int dev_set_name(struct rd *rd)
 	mnl_attr_put_u32(rd->nlh, RDMA_NLDEV_ATTR_DEV_INDEX, rd->dev_idx);
 	mnl_attr_put_strz(rd->nlh, RDMA_NLDEV_ATTR_DEV_NAME, rd_argv(rd));
 
-	return rd_send_msg(rd);
+	return rd_sendrecv_msg(rd, seq);
 }
 
 static int dev_one_set(struct rd *rd)
rdma/rdma.h +2 -0
index 1022e9a2..6c7f7d15 100644
@@ -68,6 +68,7 @@ struct rd {
 	json_writer_t *jw;
 	bool json_output;
 	bool pretty_output;
+	bool suppress_errors;
 	struct list_head filter_list;
 };
 

@@ -119,6 +120,7 @@ bool rd_is_string_filtered_attr(struct rd *rd, const char *key, const char *val,
  */
 int rd_send_msg(struct rd *rd);
 int rd_recv_msg(struct rd *rd, mnl_cb_t callback, void *data, uint32_t seq);
+int rd_sendrecv_msg(struct rd *rd, unsigned int 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);
rdma/res.h +1 -0
index b4a7e552..525171fc 100644
@@ -31,6 +31,7 @@ int res_qp_idx_parse_cb(const struct nlmsghdr *nlh, void *data);
 		if (id) {                                                              \
 			ret = rd_doit_index(rd, &idx);                                 \
 			if (ret) {                                                     \
+				rd->suppress_errors = true;                            \
 				ret = _res_send_idx_msg(rd, command,                   \
 							name##_idx_parse_cb,           \
 							idx, id);                      \
rdma/utils.c +18 -0
index 1f6bf330..11ed8a73 100644
@@ -693,10 +693,28 @@ int rd_recv_msg(struct rd *rd, mnl_cb_t callback, void *data, unsigned int seq)
 		ret = mnl_cb_run(buf, ret, seq, portid, callback, data);
 	} while (ret > 0);
 
+	if (ret < 0 && !rd->suppress_errors)
+		perror("error");
+
 	mnl_socket_close(rd->nl);
 	return ret;
 }
 
+static int null_cb(const struct nlmsghdr *nlh, void *data)
+{
+	return MNL_CB_OK;
+}
+
+int rd_sendrecv_msg(struct rd *rd, unsigned int seq)
+{
+	int ret;
+
+	ret = rd_send_msg(rd);
+	if (!ret)
+		ret = rd_recv_msg(rd, null_cb, rd, seq);
+	return ret;
+}
+
 static struct dev_map *_dev_map_lookup(struct rd *rd, const char *dev_name)
 {
 	struct dev_map *dev_map;
Signature · 1 line
2.20.1
#4 lore raw

Re: [PATCH v2 iproute2-next 2/4] rdma: add helper rd_sendrecv_msg()

Quoted 33 lines · Steve Wise

This function sends the constructed netlink message and then receives the response.

Change rd_recv_msg() to display any error messages.

Change 'rdma dev set' to use rd_sendrecv_msg().

Signed-off-by Steve Wise <[email protected]>
---
 rdma/dev.c   |  2 +-
 rdma/rdma.h  |  2 ++
 rdma/res.h   |  1 +
 rdma/utils.c | 18 ++++++++++++++++++
 4 files changed, 22 insertions(+), 1 deletion(-)
rdma/dev.c +1 -1
index 954e0015..33962520 100644
@@ -268,7 +268,7 @@ static int dev_set_name(struct rd *rd)
 	mnl_attr_put_u32(rd->nlh, RDMA_NLDEV_ATTR_DEV_INDEX, rd->dev_idx);
 	mnl_attr_put_strz(rd->nlh, RDMA_NLDEV_ATTR_DEV_NAME, rd_argv(rd));
 
-	return rd_send_msg(rd);
+	return rd_sendrecv_msg(rd, seq);
 }
 
 static int dev_one_set(struct rd *rd)
rdma/rdma.h +0 -0
index 1022e9a2..6c7f7d15 100644

rdma/rdma.h struct rd { · line 74

Quoted 7 lines
rdma/rdma.h +1 -0
@@ -68,6 +68,7 @@ struct rd {
 	json_writer_t *jw;
 	bool json_output;
 	bool pretty_output;
+	bool suppress_errors;
 	struct list_head filter_list;
 };

All of the suppress_errors seems like an unrelated change.

author
#5 lore raw

Re: [PATCH v2 iproute2-next 2/4] rdma: add helper rd_sendrecv_msg()

Quoted 29 lines · David Ahern
Quoted 27 lines · Steve Wise

This function sends the constructed netlink message and then receives the response.

Change rd_recv_msg() to display any error messages.

Change 'rdma dev set' to use rd_sendrecv_msg().

Signed-off-by Steve Wise <[email protected]>
---
 rdma/dev.c   |  2 +-
 rdma/rdma.h  |  2 ++
 rdma/res.h   |  1 +
 rdma/utils.c | 18 ++++++++++++++++++
 4 files changed, 22 insertions(+), 1 deletion(-)
rdma/dev.c +1 -1
index 954e0015..33962520 100644
@@ -268,7 +268,7 @@ static int dev_set_name(struct rd *rd)
      mnl_attr_put_u32(rd->nlh, RDMA_NLDEV_ATTR_DEV_INDEX, rd->dev_idx);
      mnl_attr_put_strz(rd->nlh, RDMA_NLDEV_ATTR_DEV_NAME, rd_argv(rd));
 
-     return rd_send_msg(rd);
+     return rd_sendrecv_msg(rd, seq);
 }
Quoted 16 lines

rdma/rdma.h struct rd { · line 74

Quoted 13 lines
rdma/dev.c +0 -0
 static int dev_one_set(struct rd *rd)
rdma/rdma.h +1 -0
index 1022e9a2..6c7f7d15 100644
@@ -68,6 +68,7 @@ struct rd {
      json_writer_t *jw;
      bool json_output;
      bool pretty_output;
+     bool suppress_errors;
      struct list_head filter_list;
 };

All of the suppress_errors seems like an unrelated change.

Hey David,

I just realized I replied only to you directly, so I'll reply again to everyone.

It is a bug fix that showed itself when I moved the error check to rd_recv_msg(), which Leon recommended in the last review cycle. The bug doesn't manifest unless this series is applied, so the suppress errors fix is really only needed as part of this series.

Thanks,

Steve.

Reviewed-by on v2 2/4
#6 lore raw

Re: [PATCH v2 iproute2-next 2/4] rdma: add helper rd_sendrecv_msg()

In reply to Steve Wise
Quoted 7 lines · Steve Wise

This function sends the constructed netlink message and then receives the response.

Change rd_recv_msg() to display any error messages.

Change 'rdma dev set' to use rd_sendrecv_msg().

Quoted 8 lines
Signed-off-by Steve Wise <[email protected]>
---
 rdma/dev.c   |  2 +-
 rdma/rdma.h  |  2 ++
 rdma/res.h   |  1 +
 rdma/utils.c | 18 ++++++++++++++++++
 4 files changed, 22 insertions(+), 1 deletion(-)

Thanks,

Reviewed-by Leon Romanovsky <[email protected]>
author
#7 lore raw

PATCH v2 3/4 rdma: add 'link add/delete' commands

In reply to Steve Wise

Add new 'link' subcommand 'add' and 'delete' to allow binding a soft-rdma device to a netdev interface.

EG:

rdma link add rxe_eth0 type rxe netdev eth0
rdma link delete rxe_eth0

Signed-off-by Steve Wise <[email protected]>
---
 rdma/link.c | 83 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 rdma/rdma.h |  2 ++
 2 files changed, 85 insertions(+)
rdma/link.c +83 -0
index 89e81b84..982c2b16 100644
@@ -9,6 +9,9 @@
 static int link_help(struct rd *rd)
 {
 	pr_out("Usage: %s link show [DEV/PORT_INDEX]\n", rd->filename);
+	pr_out("Usage: %s link add NAME type TYPE netdev NETDEV\n",
+	       rd->filename);
+	pr_out("Usage: %s link delete NAME\n", rd->filename);
 	return 0;
 }
 

@@ -336,10 +339,90 @@ static int link_show(struct rd *rd)
 	return rd_exec_link(rd, link_one_show, true);
 }
 
+static int link_add_netdev(struct rd *rd)
+{
+	rd->link_netdev = rd_argv(rd);
+	rd_arg_inc(rd);
+	return 0;
+}
+
+static int link_add_type(struct rd *rd)
+{
+	const struct rd_cmd cmds[] = {
+		{ NULL,		link_help},
+		{ "netdev",	link_add_netdev},
+		{ 0 }
+	};
+	rd->link_type = rd_argv(rd);
+	rd_arg_inc(rd);
+	return rd_exec_cmd(rd, cmds, "parameter");
+}
+
+static int link_add(struct rd *rd)
+{
+	const struct rd_cmd cmds[] = {
+		{ NULL,		link_help},
+		{ "type",	link_add_type},
+		{ 0 }
+	};
+
+	uint32_t seq;
+	char *name;
+	int ret;
+
+	if (rd_no_arg(rd)) {
+		pr_err("Please provide a link name to add.\n");
+		return -EINVAL;
+	}
+	name = rd_argv(rd);
+	rd_arg_inc(rd);
+
+	ret = rd_exec_cmd(rd, cmds, "parameter");
+	if (ret)
+		return ret;
+
+	if (!rd->link_type) {
+		pr_err("Please provide a link type name.\n");
+		return -EINVAL;
+	}
+	if (!rd->link_netdev) {
+		pr_err("Please provide a net device name.\n");
+		return -EINVAL;
+	}
+
+	rd_prepare_msg(rd, RDMA_NLDEV_CMD_NEWLINK, &seq,
+		       (NLM_F_REQUEST | NLM_F_ACK));
+	mnl_attr_put_strz(rd->nlh, RDMA_NLDEV_ATTR_DEV_NAME, name);
+	mnl_attr_put_strz(rd->nlh, RDMA_NLDEV_ATTR_LINK_TYPE, rd->link_type);
+	mnl_attr_put_strz(rd->nlh, RDMA_NLDEV_ATTR_NDEV_NAME, rd->link_netdev);
+	return rd_sendrecv_msg(rd, seq);
+}
+
+static int _link_del(struct rd *rd)
+{
+	uint32_t seq;
+
+	if (!rd_no_arg(rd)) {
+		pr_err("Unknown parameter %s\n", rd_argv(rd));
+		return -EINVAL;
+	}
+	rd_prepare_msg(rd, RDMA_NLDEV_CMD_DELLINK, &seq,
+		       (NLM_F_REQUEST | NLM_F_ACK));
+	mnl_attr_put_u32(rd->nlh, RDMA_NLDEV_ATTR_DEV_INDEX, rd->dev_idx);
+	return rd_sendrecv_msg(rd, seq);
+}
+
+static int link_del(struct rd *rd)
+{
+	return rd_exec_require_dev(rd, _link_del);
+}
+
 int cmd_link(struct rd *rd)
 {
 	const struct rd_cmd cmds[] = {
 		{ NULL,		link_show },
+		{ "add",	link_add },
+		{ "delete",	link_del },
 		{ "show",	link_show },
 		{ "list",	link_show },
 		{ "help",	link_help },
rdma/rdma.h +2 -0
index 6c7f7d15..070c8ddf 100644
@@ -70,6 +70,8 @@ struct rd {
 	bool pretty_output;
 	bool suppress_errors;
 	struct list_head filter_list;
+	char *link_type;
+	char *link_netdev;
 };
 
 struct rd_cmd {
Signature · 1 line
2.20.1
Reviewed-by on v2 3/4
#8 lore raw

Re: [PATCH v2 iproute2-next 3/4] rdma: add 'link add/delete' commands

Quoted 5 lines · Steve Wise

Add new 'link' subcommand 'add' and 'delete' to allow binding a soft-rdma device to a netdev interface.

EG:

Quoted 9 lines

rdma link add rxe_eth0 type rxe netdev eth0
rdma link delete rxe_eth0

Signed-off-by Steve Wise <[email protected]>
---
 rdma/link.c | 83 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 rdma/rdma.h |  2 ++
 2 files changed, 85 insertions(+)

Thanks,

Reviewed-by Leon Romanovsky <[email protected]>
#9 lore raw

Re: [PATCH v2 iproute2-next 3/4] rdma: add 'link add/delete' commands

In reply to Steve Wise
Quoted 72 lines · Steve Wise

Add new 'link' subcommand 'add' and 'delete' to allow binding a soft-rdma device to a netdev interface.

EG:

rdma link add rxe_eth0 type rxe netdev eth0
rdma link delete rxe_eth0

Signed-off-by Steve Wise <[email protected]>
---
 rdma/link.c | 83 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 rdma/rdma.h |  2 ++
 2 files changed, 85 insertions(+)
rdma/link.c +43 -0
index 89e81b84..982c2b16 100644
@@ -9,6 +9,9 @@
 static int link_help(struct rd *rd)
 {
 	pr_out("Usage: %s link show [DEV/PORT_INDEX]\n", rd->filename);
+	pr_out("Usage: %s link add NAME type TYPE netdev NETDEV\n",
+	       rd->filename);
+	pr_out("Usage: %s link delete NAME\n", rd->filename);
 	return 0;
 }
 

@@ -336,10 +339,90 @@ static int link_show(struct rd *rd)
 	return rd_exec_link(rd, link_one_show, true);
 }
 
+static int link_add_netdev(struct rd *rd)
+{
+	rd->link_netdev = rd_argv(rd);
+	rd_arg_inc(rd);
+	return 0;
+}
+
+static int link_add_type(struct rd *rd)
+{
+	const struct rd_cmd cmds[] = {
+		{ NULL,		link_help},
+		{ "netdev",	link_add_netdev},
+		{ 0 }
+	};
+	rd->link_type = rd_argv(rd);
+	rd_arg_inc(rd);
+	return rd_exec_cmd(rd, cmds, "parameter");
+}
+
+static int link_add(struct rd *rd)
+{
+	const struct rd_cmd cmds[] = {
+		{ NULL,		link_help},
+		{ "type",	link_add_type},
+		{ 0 }
+	};
+
+	uint32_t seq;
+	char *name;
+	int ret;
+
+	if (rd_no_arg(rd)) {
+		pr_err("Please provide a link name to add.\n");
+		return -EINVAL;
+	}
+	name = rd_argv(rd);
+	rd_arg_inc(rd);
+
+	ret = rd_exec_cmd(rd, cmds, "parameter");
+	if (ret)

rdma/link.c static int link_show(struct rd *rd) · line 391

Quoted 10 lines
rdma/link.c +10 -0
+		return ret;
+
+	if (!rd->link_type) {
+		pr_err("Please provide a link type name.\n");
+		return -EINVAL;
+	}
+	if (!rd->link_netdev) {
+		pr_err("Please provide a net device name.\n");
+		return -EINVAL;
+	}

After a little bit more thinking, the checks above are supposed to be part of rd_exec_cmd() execution of chains. E.g if (!rd->link_type) needs to be inside link_add_type().

Quoted 53 lines
rdma/link.c +30 -0
+
+	rd_prepare_msg(rd, RDMA_NLDEV_CMD_NEWLINK, &seq,
+		       (NLM_F_REQUEST | NLM_F_ACK));
+	mnl_attr_put_strz(rd->nlh, RDMA_NLDEV_ATTR_DEV_NAME, name);
+	mnl_attr_put_strz(rd->nlh, RDMA_NLDEV_ATTR_LINK_TYPE, rd->link_type);
+	mnl_attr_put_strz(rd->nlh, RDMA_NLDEV_ATTR_NDEV_NAME, rd->link_netdev);
+	return rd_sendrecv_msg(rd, seq);
+}
+
+static int _link_del(struct rd *rd)
+{
+	uint32_t seq;
+
+	if (!rd_no_arg(rd)) {
+		pr_err("Unknown parameter %s\n", rd_argv(rd));
+		return -EINVAL;
+	}
+	rd_prepare_msg(rd, RDMA_NLDEV_CMD_DELLINK, &seq,
+		       (NLM_F_REQUEST | NLM_F_ACK));
+	mnl_attr_put_u32(rd->nlh, RDMA_NLDEV_ATTR_DEV_INDEX, rd->dev_idx);
+	return rd_sendrecv_msg(rd, seq);
+}
+
+static int link_del(struct rd *rd)
+{
+	return rd_exec_require_dev(rd, _link_del);
+}
+
 int cmd_link(struct rd *rd)
 {
 	const struct rd_cmd cmds[] = {
 		{ NULL,		link_show },
+		{ "add",	link_add },
+		{ "delete",	link_del },
 		{ "show",	link_show },
 		{ "list",	link_show },
 		{ "help",	link_help },
rdma/rdma.h +2 -1
index 6c7f7d15..070c8ddf 100644
@@ -70,6 +70,8 @@ struct rd {
 	bool pretty_output;
 	bool suppress_errors;
 	struct list_head filter_list;
+	char *link_type;
+	char *link_netdev;
 };
 
 struct rd_cmd {
--

2.20.1

author
#10 lore raw

Re: [PATCH v2 iproute2-next 3/4] rdma: add 'link add/delete' commands

Quoted 80 lines · Leon Romanovsky
Quoted 78 lines · Steve Wise

Add new 'link' subcommand 'add' and 'delete' to allow binding a soft-rdma device to a netdev interface.

EG:

rdma link add rxe_eth0 type rxe netdev eth0
rdma link delete rxe_eth0

Signed-off-by Steve Wise <[email protected]>
---
 rdma/link.c | 83 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 rdma/rdma.h |  2 ++
 2 files changed, 85 insertions(+)
rdma/link.c +49 -0
index 89e81b84..982c2b16 100644
@@ -9,6 +9,9 @@
 static int link_help(struct rd *rd)
 {
      pr_out("Usage: %s link show [DEV/PORT_INDEX]\n", rd->filename);
+     pr_out("Usage: %s link add NAME type TYPE netdev NETDEV\n",
+            rd->filename);
+     pr_out("Usage: %s link delete NAME\n", rd->filename);
      return 0;
 }
 

@@ -336,10 +339,90 @@ static int link_show(struct rd *rd)
      return rd_exec_link(rd, link_one_show, true);
 }
 
+static int link_add_netdev(struct rd *rd)
+{
+     rd->link_netdev = rd_argv(rd);
+     rd_arg_inc(rd);
+     return 0;
+}
+
+static int link_add_type(struct rd *rd)
+{
+     const struct rd_cmd cmds[] = {
+             { NULL,         link_help},
+             { "netdev",     link_add_netdev},
+             { 0 }
+     };
+     rd->link_type = rd_argv(rd);
+     rd_arg_inc(rd);
+     return rd_exec_cmd(rd, cmds, "parameter");
+}
+
+static int link_add(struct rd *rd)
+{
+     const struct rd_cmd cmds[] = {
+             { NULL,         link_help},
+             { "type",       link_add_type},
+             { 0 }
+     };
+
+     uint32_t seq;
+     char *name;
+     int ret;
+
+     if (rd_no_arg(rd)) {
+             pr_err("Please provide a link name to add.\n");
+             return -EINVAL;
+     }
+     name = rd_argv(rd);
+     rd_arg_inc(rd);
+
+     ret = rd_exec_cmd(rd, cmds, "parameter");
+     if (ret)
+             return ret;
+
+     if (!rd->link_type) {
+             pr_err("Please provide a link type name.\n");
+             return -EINVAL;
+     }
Quoted 9 lines

rdma/link.c static int link_show(struct rd *rd) · line 391

Quoted 4 lines
rdma/link.c +4 -0
+     if (!rd->link_netdev) {
+             pr_err("Please provide a net device name.\n");
+             return -EINVAL;
+     }

After a little bit more thinking, the checks above are supposed to be part of rd_exec_cmd() execution of chains. E.g if (!rd->link_type) needs to be inside link_add_type().

Ok. I'll respin and add your reviewed-by tags.

Thanks,
Steve

author
#11 lore raw

PATCH v2 4/4 rdma: man page update for link add/delete

In reply to Steve Wise

Update the 'rdma link' man page with 'link add/delete' info.

Signed-off-by Steve Wise <[email protected]>
---
 man/man8/rdma-link.8 | 47 ++++++++++++++++++++++++++++++++++++++++++++
 1 file changed, 47 insertions(+)
man/man8/rdma-link.8 +47 -0
index bddf3474..b3b40de7 100644
@@ -22,6 +22,18 @@ rdma-link \- rdma link configuration
 .B rdma link show
 .RI "[ " DEV/PORT_INDEX " ]"
 
+.ti -8
+.B rdma link add
+.BR NAME
+.BR type
+.BR TYPE
+.BR netdev
+.BR NETDEV
+
+.ti -8
+.B rdma link delete
+.RI NAME
+
 .ti -8
 .B rdma link help
 

@@ -33,6 +45,31 @@ rdma-link \- rdma link configuration
 - specifies the RDMA link to show.
 If this argument is omitted all links are listed.
 
+.SS rdma link add NAME type TYPE netdev NETDEV - add an rdma link for the specified type to the network device
+.sp
+.BR NAME
+- specifies the new name of the rdma link to add
+
+.BR TYPE
+- specifies which rdma type to use.  Link types:
+.sp
+.in +8
+.B rxe
+- Soft RoCE driver
+.sp
+.B siw
+- Soft iWARP driver
+.in -8
+
+.BR NETDEV
+- specifies the network device to which the link is bound
+
+.SS rdma link delete NAME - delete an rdma link
+.PP
+.BR NAME
+- specifies the name of the rdma link to delete
+.PP
+
 .SH "EXAMPLES"
 .PP
 rdma link show

@@ -45,6 +82,16 @@ rdma link show mlx5_2/1
 Shows the state of specified rdma link.
 .RE
 .PP
+rdma link add rxe_eth0 type rxe netdev eth0
+.RS 4
+Adds a RXE link named rxe_eth0 to network device eth0
+.RE
+.PP
+rdma link del rxe_eth0
+.RS 4
+Removes RXE link rxe_eth0
+.RE
+.PP
 
 .SH SEE ALSO
 .BR rdma (8),
Signature · 1 line
2.20.1