net/smc: Add support for obtaining system information

Add new netlink command to obtain system information
of the smc module.

Signed-off-by: Guvenc Gulce <guvenc@linux.ibm.com>
Signed-off-by: Karsten Graul <kgraul@linux.ibm.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

1 files changed, 60 insertions, 0 deletions

diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c
index 0088511e30bf..c7b1c62c2f2e 100644
--- a/net/smc/smc_core.c
+++ b/net/smc/smc_core.c
@@ -16,6 +16,8 @@
 #include <linux/wait.h>
 #include <linux/reboot.h>
 #include <linux/mutex.h>
+#include <linux/list.h>
+#include <linux/smc.h>
 #include <net/tcp.h>
 #include <net/sock.h>
 #include <rdma/ib_verbs.h>
@@ -30,6 +32,7 @@
 #include "smc_cdc.h"
 #include "smc_close.h"
 #include "smc_ism.h"
+#include "smc_netlink.h"
 
 #define SMC_LGR_NUM_INCR		256
 #define SMC_LGR_FREE_DELAY_SERV		(600 * HZ)
@@ -214,6 +217,63 @@ static void smc_lgr_unregister_conn(struct smc_connection *conn)
 	conn->lgr = NULL;
 }
 
+int smc_nl_get_sys_info(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	struct smc_nl_dmp_ctx *cb_ctx = smc_nl_dmp_ctx(cb);
+	char hostname[SMC_MAX_HOSTNAME_LEN + 1];
+	char smc_seid[SMC_MAX_EID_LEN + 1];
+	struct smcd_dev *smcd_dev;
+	struct nlattr *attrs;
+	u8 *seid = NULL;
+	u8 *host = NULL;
+	void *nlh;
+
+	nlh = genlmsg_put(skb, NETLINK_CB(cb->skb).portid, cb->nlh->nlmsg_seq,
+			  &smc_gen_nl_family, NLM_F_MULTI,
+			  SMC_NETLINK_GET_SYS_INFO);
+	if (!nlh)
+		goto errmsg;
+	if (cb_ctx->pos[0])
+		goto errout;
+	attrs = nla_nest_start(skb, SMC_GEN_SYS_INFO);
+	if (!attrs)
+		goto errout;
+	if (nla_put_u8(skb, SMC_NLA_SYS_VER, SMC_V2))
+		goto errattr;
+	if (nla_put_u8(skb, SMC_NLA_SYS_REL, SMC_RELEASE))
+		goto errattr;
+	if (nla_put_u8(skb, SMC_NLA_SYS_IS_ISM_V2, smc_ism_is_v2_capable()))
+		goto errattr;
+	smc_clc_get_hostname(&host);
+	if (host) {
+		snprintf(hostname, sizeof(hostname), "%s", host);
+		if (nla_put_string(skb, SMC_NLA_SYS_LOCAL_HOST, hostname))
+			goto errattr;
+	}
+	mutex_lock(&smcd_dev_list.mutex);
+	smcd_dev = list_first_entry_or_null(&smcd_dev_list.list,
+					    struct smcd_dev, list);
+	if (smcd_dev)
+		smc_ism_get_system_eid(smcd_dev, &seid);
+	mutex_unlock(&smcd_dev_list.mutex);
+	if (seid && smc_ism_is_v2_capable()) {
+		snprintf(smc_seid, sizeof(smc_seid), "%s", seid);
+		if (nla_put_string(skb, SMC_NLA_SYS_SEID, smc_seid))
+			goto errattr;
+	}
+	nla_nest_end(skb, attrs);
+	genlmsg_end(skb, nlh);
+	cb_ctx->pos[0] = 1;
+	return skb->len;
+
+errattr:
+	nla_nest_cancel(skb, attrs);
+errout:
+	genlmsg_cancel(skb, nlh);
+errmsg:
+	return skb->len;
+}
+
 void smc_lgr_cleanup_early(struct smc_connection *conn)
 {
 	struct smc_link_group *lgr = conn->lgr;