net/smc: Introduce IPPROTO_SMC

This patch allows to create smc socket via AF_INET, similar to the following code, /* create v4 smc sock */ v4 = socket(AF_INET, SOCK_STREAM, IPPROTO_SMC); /* create v6 smc sock */ v6 = socket(AF_INET6, SOCK_STREAM, IPPROTO_SMC); There are several reasons why we believe it is appropriate here: 1. For smc sockets, it actually use IPv4 (AF-INET) or IPv6 (AF-INET6) address. There is no AF_SMC address at all. 2. Create smc socket in the AF_INET(6) path, which allows us to reuse the infrastructure of AF_INET(6) path, such as common ebpf hooks. Otherwise, smc have to implement it again in AF_SMC path.

D. Wythe committed 2 years ago

Commit d25a92c1 parent 13543d05 files · +198 −3Browse files

Unified · Split

5 files

include/uapi/linux/in.h +2 −0
net/smc/Makefile +1 −1
net/smc/af_smc.c +14 −2
net/smc/smc_inet.c +159 −0
net/smc/smc_inet.h +22 −0

include/uapi/linux/in.h+2−0

 #define IPPROTO_ETHERNET	IPPROTO_ETHERNET
   IPPROTO_RAW = 255,		/* Raw IP packets			*/
 #define IPPROTO_RAW		IPPROTO_RAW
+  IPPROTO_SMC = 256,		/* Shared Memory Communications		*/
+#define IPPROTO_SMC		IPPROTO_SMC
   IPPROTO_MPTCP = 262,		/* Multipath TCP connection		*/
 #define IPPROTO_MPTCP		IPPROTO_MPTCP
   IPPROTO_MAX

net/smc/Makefile+1−1

@@ -4,6 +4,6 @@ obj-$(CONFIG_SMC) += smc.o · 3 unmodified lines
4	obj-$(CONFIG_SMC_DIAG) += smc_diag.o	4	obj-$(CONFIG_SMC_DIAG) += smc_diag.o
5	smc-y := af_smc.o smc_pnet.o smc_ib.o smc_clc.o smc_core.o smc_wr.o smc_llc.o	5	smc-y := af_smc.o smc_pnet.o smc_ib.o smc_clc.o smc_core.o smc_wr.o smc_llc.o
6	smc-y += smc_cdc.o smc_tx.o smc_rx.o smc_close.o smc_ism.o smc_netlink.o smc_stats.o	6	smc-y += smc_cdc.o smc_tx.o smc_rx.o smc_close.o smc_ism.o smc_netlink.o smc_stats.o
7	smc-y += smc_tracepoint.o	7	smc-y += smc_tracepoint.o smc_inet.o
8	smc-$(CONFIG_SYSCTL) += smc_sysctl.o	8	smc-$(CONFIG_SYSCTL) += smc_sysctl.o
9	smc-$(CONFIG_SMC_LO) += smc_loopback.o	9	smc-$(CONFIG_SMC_LO) += smc_loopback.o

net/smc/af_smc.c+14−2

@@ -54,6 +54,7 @@ · 53 unmodified lines
54	#include "smc_tracepoint.h"	54	#include "smc_tracepoint.h"
55	#include "smc_sysctl.h"	55	#include "smc_sysctl.h"
56	#include "smc_loopback.h"	56	#include "smc_loopback.h"
		57	#include "smc_inet.h"
57		58
58	static DEFINE_MUTEX(smc_server_lgr_pending); /* serialize link group	59	static DEFINE_MUTEX(smc_server_lgr_pending); /* serialize link group
59	* creation on server	60	* creation on server
@@ -3575,10 +3576,15 @@ static int __init smc_init(void) · 3515 unmodified lines
3575	pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);	3576	pr_err("%s: tcp_ulp_register fails with %d\n", __func__, rc);
3576	goto out_lo;	3577	goto out_lo;
3577	}	3578	}
3578		3579	rc = smc_inet_init();
		3580	if (rc) {
		3581	pr_err("%s: smc_inet_init fails with %d\n", __func__, rc);
		3582	goto out_ulp;
		3583	}
3579	static_branch_enable(&tcp_have_smc);	3584	static_branch_enable(&tcp_have_smc);
3580	return 0;	3585	return 0;
3581		3586	out_ulp:
		3587	tcp_unregister_ulp(&smc_ulp_ops);
3582	out_lo:	3588	out_lo:
3583	smc_loopback_exit();	3589	smc_loopback_exit();
3584	out_ib:	3590	out_ib:
@@ -3615,6 +3621,7 @@ out_pernet_subsys: · 30 unmodified lines
3615	static void __exit smc_exit(void)	3621	static void __exit smc_exit(void)
3616	{	3622	{
3617	static_branch_disable(&tcp_have_smc);	3623	static_branch_disable(&tcp_have_smc);
		3624	smc_inet_exit();
3618	tcp_unregister_ulp(&smc_ulp_ops);	3625	tcp_unregister_ulp(&smc_ulp_ops);
3619	sock_unregister(PF_SMC);	3626	sock_unregister(PF_SMC);
3620	smc_core_exit();	3627	smc_core_exit();
@@ -3642,4 +3649,9 @@ MODULE_DESCRIPTION("smc socket address family"); · 21 unmodified lines
3642	MODULE_LICENSE("GPL");	3649	MODULE_LICENSE("GPL");
3643	MODULE_ALIAS_NETPROTO(PF_SMC);	3650	MODULE_ALIAS_NETPROTO(PF_SMC);
3644	MODULE_ALIAS_TCP_ULP("smc");	3651	MODULE_ALIAS_TCP_ULP("smc");
		3652	/* 256 for IPPROTO_SMC and 1 for SOCK_STREAM */
		3653	MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET, 256, 1);
		3654	#if IS_ENABLED(CONFIG_IPV6)
		3655	MODULE_ALIAS_NET_PF_PROTO_TYPE(PF_INET6, 256, 1);
		3656	#endif /* CONFIG_IPV6 */
3645	MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);	3657	MODULE_ALIAS_GENL_FAMILY(SMC_GENL_FAMILY_NAME);

net/smc/smc_inet.c+159−0

@@ -0,0 +1,159 @@
	1	// SPDX-License-Identifier: GPL-2.0-only
	2	/*
	3	* Shared Memory Communications over RDMA (SMC-R) and RoCE
	4	*
	5	* Definitions for the IPPROTO_SMC (socket related)
	6	*
	7	* Copyright IBM Corp. 2016, 2018
	8	* Copyright (c) 2024, Alibaba Inc.
	9	*
	10	* Author: D. Wythe <alibuda@linux.alibaba.com>
	11	*/
	12
	13	#include <net/protocol.h>
	14	#include <net/sock.h>
	15
	16	#include "smc_inet.h"
	17	#include "smc.h"
	18
	19	static int smc_inet_init_sock(struct sock *sk);
	20
	21	static struct proto smc_inet_prot = {
	22	.name = "INET_SMC",
	23	.owner = THIS_MODULE,
	24	.init = smc_inet_init_sock,
	25	.hash = smc_hash_sk,
	26	.unhash = smc_unhash_sk,
	27	.release_cb = smc_release_cb,
	28	.obj_size = sizeof(struct smc_sock),
	29	.h.smc_hash = &smc_v4_hashinfo,
	30	.slab_flags = SLAB_TYPESAFE_BY_RCU,
	31	};
	32
	33	static const struct proto_ops smc_inet_stream_ops = {
	34	.family = PF_INET,
	35	.owner = THIS_MODULE,
	36	.release = smc_release,
	37	.bind = smc_bind,
	38	.connect = smc_connect,
	39	.socketpair = sock_no_socketpair,
	40	.accept = smc_accept,
	41	.getname = smc_getname,
	42	.poll = smc_poll,
	43	.ioctl = smc_ioctl,
	44	.listen = smc_listen,
	45	.shutdown = smc_shutdown,
	46	.setsockopt = smc_setsockopt,
	47	.getsockopt = smc_getsockopt,
	48	.sendmsg = smc_sendmsg,
	49	.recvmsg = smc_recvmsg,
	50	.mmap = sock_no_mmap,
	51	.splice_read = smc_splice_read,
	52	};
	53
	54	static struct inet_protosw smc_inet_protosw = {
	55	.type = SOCK_STREAM,
	56	.protocol = IPPROTO_SMC,
	57	.prot = &smc_inet_prot,
	58	.ops = &smc_inet_stream_ops,
	59	.flags = INET_PROTOSW_ICSK,
	60	};
	61
	62	#if IS_ENABLED(CONFIG_IPV6)
	63	static struct proto smc_inet6_prot = {
	64	.name = "INET6_SMC",
	65	.owner = THIS_MODULE,
	66	.init = smc_inet_init_sock,
	67	.hash = smc_hash_sk,
	68	.unhash = smc_unhash_sk,
	69	.release_cb = smc_release_cb,
	70	.obj_size = sizeof(struct smc_sock),
	71	.h.smc_hash = &smc_v6_hashinfo,
	72	.slab_flags = SLAB_TYPESAFE_BY_RCU,
	73	};
	74
	75	static const struct proto_ops smc_inet6_stream_ops = {
	76	.family = PF_INET6,
	77	.owner = THIS_MODULE,
	78	.release = smc_release,
	79	.bind = smc_bind,
	80	.connect = smc_connect,
	81	.socketpair = sock_no_socketpair,
	82	.accept = smc_accept,
	83	.getname = smc_getname,
	84	.poll = smc_poll,
	85	.ioctl = smc_ioctl,
	86	.listen = smc_listen,
	87	.shutdown = smc_shutdown,
	88	.setsockopt = smc_setsockopt,
	89	.getsockopt = smc_getsockopt,
	90	.sendmsg = smc_sendmsg,
	91	.recvmsg = smc_recvmsg,
	92	.mmap = sock_no_mmap,
	93	.splice_read = smc_splice_read,
	94	};
	95
	96	static struct inet_protosw smc_inet6_protosw = {
	97	.type = SOCK_STREAM,
	98	.protocol = IPPROTO_SMC,
	99	.prot = &smc_inet6_prot,
	100	.ops = &smc_inet6_stream_ops,
	101	.flags = INET_PROTOSW_ICSK,
	102	};
	103	#endif /* CONFIG_IPV6 */
	104
	105	static int smc_inet_init_sock(struct sock *sk)
	106	{
	107	struct net *net = sock_net(sk);
	108
	109	/* init common smc sock */
	110	smc_sk_init(net, sk, IPPROTO_SMC);
	111	/* create clcsock */
	112	return smc_create_clcsk(net, sk, sk->sk_family);
	113	}
	114
	115	int __init smc_inet_init(void)
	116	{
	117	int rc;
	118
	119	rc = proto_register(&smc_inet_prot, 1);
	120	if (rc) {
	121	pr_err("%s: proto_register smc_inet_prot fails with %d\n",
	122	__func__, rc);
	123	return rc;
	124	}
	125	/* no return value */
	126	inet_register_protosw(&smc_inet_protosw);
	127
	128	#if IS_ENABLED(CONFIG_IPV6)
	129	rc = proto_register(&smc_inet6_prot, 1);
	130	if (rc) {
	131	pr_err("%s: proto_register smc_inet6_prot fails with %d\n",
	132	__func__, rc);
	133	goto out_inet6_prot;
	134	}
	135	rc = inet6_register_protosw(&smc_inet6_protosw);
	136	if (rc) {
	137	pr_err("%s: inet6_register_protosw smc_inet6_protosw fails with %d\n",
	138	__func__, rc);
	139	goto out_inet6_protosw;
	140	}
	141	return rc;
	142	out_inet6_protosw:
	143	proto_unregister(&smc_inet6_prot);
	144	out_inet6_prot:
	145	inet_unregister_protosw(&smc_inet_protosw);
	146	proto_unregister(&smc_inet_prot);
	147	#endif /* CONFIG_IPV6 */
	148	return rc;
	149	}
	150
	151	void smc_inet_exit(void)
	152	{
	153	#if IS_ENABLED(CONFIG_IPV6)
	154	inet6_unregister_protosw(&smc_inet6_protosw);
	155	proto_unregister(&smc_inet6_prot);
	156	#endif /* CONFIG_IPV6 */
	157	inet_unregister_protosw(&smc_inet_protosw);
	158	proto_unregister(&smc_inet_prot);
	159	}

net/smc/smc_inet.h+22−0

@@ -0,0 +1,22 @@
	1	/* SPDX-License-Identifier: GPL-2.0 */
	2	/*
	3	* Shared Memory Communications over RDMA (SMC-R) and RoCE
	4	*
	5	* Definitions for the IPPROTO_SMC (socket related)
	6
	7	* Copyright IBM Corp. 2016
	8	* Copyright (c) 2024, Alibaba Inc.
	9	*
	10	* Author: D. Wythe <alibuda@linux.alibaba.com>
	11	*/
	12	#ifndef __INET_SMC
	13	#define __INET_SMC
	14
	15	/* Initialize protocol registration on IPPROTO_SMC,
	16	* @return 0 on success
	17	*/
	18	int smc_inet_init(void);
	19
	20	void smc_inet_exit(void);
	21
	22	#endif /* __INET_SMC */