net/smc: Introduce generic netlink interface for diagnostic purposes

Introduce generic netlink interface infrastructure to expose
the diagnostic information regarding smc linkgroups, links and devices.

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>

diff --git a/include/uapi/linux/smc.h b/include/uapi/linux/smc.h
index 0e11ca4..b604d64 100644 (file)
--- a/include/uapi/linux/smc.h
+++ b/include/uapi/linux/smc.h
@@ -33,4 +33,15 @@ enum {                               /* SMC PNET Table commands */
 #define SMCR_GENL_FAMILY_NAME          "SMC_PNETID"
 #define SMCR_GENL_FAMILY_VERSION       1
 
+/* gennetlink interface to access non-socket information from SMC module */
+#define SMC_GENL_FAMILY_NAME           "SMC_GEN_NETLINK"
+#define SMC_GENL_FAMILY_VERSION                1
+
+/* SMC_GENL_FAMILY top level attributes */
+enum {
+       SMC_GEN_UNSPEC,
+       __SMC_GEN_MAX,
+       SMC_GEN_MAX = __SMC_GEN_MAX - 1
+};
+
 #endif /* _UAPI_LINUX_SMC_H */

diff --git a/net/smc/Makefile b/net/smc/Makefile
index cb12545..77e54fe 100644 (file)
--- a/net/smc/Makefile
+++ b/net/smc/Makefile
@@ -2,4 +2,4 @@
 obj-$(CONFIG_SMC)      += smc.o
 obj-$(CONFIG_SMC_DIAG) += smc_diag.o
 smc-y := af_smc.o smc_pnet.o smc_ib.o smc_clc.o smc_core.o smc_wr.o smc_llc.o
-smc-y += smc_cdc.o smc_tx.o smc_rx.o smc_close.o smc_ism.o
+smc-y += smc_cdc.o smc_tx.o smc_rx.o smc_close.o smc_ism.o smc_netlink.o

diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c
index f79b59a..47340b3 100644 (file)
--- a/net/smc/af_smc.c
+++ b/net/smc/af_smc.c
@@ -45,6 +45,7 @@
 #include "smc_ib.h"
 #include "smc_ism.h"
 #include "smc_pnet.h"
+#include "smc_netlink.h"
 #include "smc_tx.h"
 #include "smc_rx.h"
 #include "smc_close.h"
@@ -2495,10 +2496,14 @@ static int __init smc_init(void)
        smc_ism_init();
        smc_clc_init();
 
-       rc = smc_pnet_init();
+       rc = smc_nl_init();
        if (rc)
                goto out_pernet_subsys;
 
+       rc = smc_pnet_init();
+       if (rc)
+               goto out_nl;
+
        rc = -ENOMEM;
        smc_hs_wq = alloc_workqueue("smc_hs_wq", 0, 0);
        if (!smc_hs_wq)
@@ -2569,6 +2574,8 @@ out_alloc_hs_wq:
        destroy_workqueue(smc_hs_wq);
 out_pnet:
        smc_pnet_exit();
+out_nl:
+       smc_nl_exit();
 out_pernet_subsys:
        unregister_pernet_subsys(&smc_net_ops);
 
@@ -2586,6 +2593,7 @@ static void __exit smc_exit(void)
        proto_unregister(&smc_proto6);
        proto_unregister(&smc_proto);
        smc_pnet_exit();
+       smc_nl_exit();
        unregister_pernet_subsys(&smc_net_ops);
        rcu_barrier();
 }

diff --git a/net/smc/smc_netlink.c b/net/smc/smc_netlink.c
new file mode 100644 (file)
index 0000000..4f964d0
--- /dev/null
+++ b/net/smc/smc_netlink.c
@@ -0,0 +1,53 @@
+// SPDX-License-Identifier: GPL-2.0
+/*
+ *  Shared Memory Communications over RDMA (SMC-R) and RoCE
+ *
+ *  Generic netlink support functions to interact with SMC module
+ *
+ *  Copyright IBM Corp. 2020
+ *
+ *  Author(s): Guvenc Gulce <guvenc@linux.ibm.com>
+ */
+
+#include <linux/module.h>
+#include <linux/list.h>
+#include <linux/ctype.h>
+#include <linux/mutex.h>
+#include <linux/if.h>
+#include <linux/smc.h>
+
+#include "smc_core.h"
+#include "smc_netlink.h"
+
+#define SMC_CMD_MAX_ATTR 1
+
+/* SMC_GENL generic netlink operation definition */
+static const struct genl_ops smc_gen_nl_ops[] = {
+};
+
+static const struct nla_policy smc_gen_nl_policy[2] = {
+       [SMC_CMD_MAX_ATTR]      = { .type = NLA_REJECT, },
+};
+
+/* SMC_GENL family definition */
+struct genl_family smc_gen_nl_family __ro_after_init = {
+       .hdrsize =      0,
+       .name =         SMC_GENL_FAMILY_NAME,
+       .version =      SMC_GENL_FAMILY_VERSION,
+       .maxattr =      SMC_CMD_MAX_ATTR,
+       .policy =       smc_gen_nl_policy,
+       .netnsok =      true,
+       .module =       THIS_MODULE,
+       .ops =          smc_gen_nl_ops,
+       .n_ops =        ARRAY_SIZE(smc_gen_nl_ops)
+};
+
+int __init smc_nl_init(void)
+{
+       return genl_register_family(&smc_gen_nl_family);
+}
+
+void smc_nl_exit(void)
+{
+       genl_unregister_family(&smc_gen_nl_family);
+}

diff --git a/net/smc/smc_netlink.h b/net/smc/smc_netlink.h
new file mode 100644 (file)
index 0000000..0c75723
--- /dev/null
+++ b/net/smc/smc_netlink.h
@@ -0,0 +1,23 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Shared Memory Communications over RDMA (SMC-R) and RoCE
+ *
+ *  SMC Generic netlink operations
+ *
+ *  Copyright IBM Corp. 2020
+ *
+ *  Author(s): Guvenc Gulce <guvenc@linux.ibm.com>
+ */
+
+#ifndef _SMC_NETLINK_H
+#define _SMC_NETLINK_H
+
+#include <net/netlink.h>
+#include <net/genetlink.h>
+
+extern struct genl_family smc_gen_nl_family;
+
+int smc_nl_init(void) __init;
+void smc_nl_exit(void);
+
+#endif