Subject: [PATCH iproute2-next] rdma: Add support for the netlink extack

From: Leon Romanovsky <[email-masked]>
Date: Thu, 31 Dec 2020 07:42:17 +0200

From: Patrisious Haddad <[email-masked]>

Add support in rdma for extack errors to be received
in userspace when sent from kernel, so now netlink extack
error messages sent from kernel would be printed for the
user.

Signed-off-by: Patrisious Haddad <[email-masked]>
Signed-off-by: Leon Romanovsky <[email-masked]>
---
Kernel part:
https://lore.kernel.org/linux-rdma/[email-masked]
---
 rdma/rdma.h  |  1 +
 rdma/utils.c | 24 ++++++++++--------------
 2 files changed, 11 insertions(+), 14 deletions(-)

diff --git a/rdma/rdma.h b/rdma/rdma.h
index fc8bcf09..470e11c8 100644
--- a/rdma/rdma.h
+++ b/rdma/rdma.h
@@ -19,6 +19,7 @@

 #include "list.h"
 #include "utils.h"
+#include "mnl_utils.h"
 #include "json_print.h"

 #define pr_err(args...) fprintf(stderr, ##args)
diff --git a/rdma/utils.c b/rdma/utils.c
index 2a201aa4..927e2107 100644
--- a/rdma/utils.c
+++ b/rdma/utils.c
@@ -664,7 +664,7 @@ void rd_prepare_msg(struct rd *rd, uint32_t cmd, uint32_t *seq, uint16_t flags)

 int rd_send_msg(struct rd *rd)
 {
-	int ret;
+	int ret, one;

 	rd->nl = mnl_socket_open(NETLINK_RDMA);
 	if (!rd->nl) {
@@ -672,6 +672,12 @@ int rd_send_msg(struct rd *rd)
 		return -ENODEV;
 	}

+	ret = mnl_socket_setsockopt(rd->nl, NETLINK_EXT_ACK, &one, sizeof(one));
+	if (ret < 0) {
+		pr_err("Failed to set socket option with err %d\n", ret);
+		goto err;
+	}
+
 	ret = mnl_socket_bind(rd->nl, 0, MNL_SOCKET_AUTOPID);
 	if (ret < 0) {
 		pr_err("Failed to bind socket with err %d\n", ret);
@@ -692,23 +698,13 @@ err:

 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];
+	int ret;

-	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);
-
+	ret = mnlu_socket_recv_run(rd->nl, seq, buf, MNL_SOCKET_BUFFER_SIZE,
+				   callback, data);
 	if (ret < 0 && !rd->suppress_errors)
 		perror("error");
-
-	mnl_socket_close(rd->nl);
 	return ret;
 }

--
2.29.2