From ac7138746e14137a451f8539614cdd349153e0c0 Mon Sep 17 00:00:00 2001 From: Ursula Braun Date: Mon, 9 Jan 2017 16:55:13 +0100 Subject: smc: establish new socket family * enable smc module loading and unloading * register new socket family * basic smc socket creation and deletion * use backing TCP socket to run CLC (Connection Layer Control) handshake of SMC protocol * Setup for infiniband traffic is implemented in follow-on patches. For now fallback to TCP socket is always used. Signed-off-by: Ursula Braun Reviewed-by: Utz Bacher Signed-off-by: David S. Miller --- net/smc/Kconfig | 11 + net/smc/Makefile | 2 + net/smc/af_smc.c | 620 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ net/smc/smc.h | 37 ++++ 4 files changed, 670 insertions(+) create mode 100644 net/smc/Kconfig create mode 100644 net/smc/Makefile create mode 100644 net/smc/af_smc.c create mode 100644 net/smc/smc.h (limited to 'net/smc') diff --git a/net/smc/Kconfig b/net/smc/Kconfig new file mode 100644 index 000000000000..bc029803e728 --- /dev/null +++ b/net/smc/Kconfig @@ -0,0 +1,11 @@ +config SMC + tristate "SMC socket protocol family" + depends on INET && INFINIBAND + ---help--- + SMC-R provides a "sockets over RDMA" solution making use of + RDMA over Converged Ethernet (RoCE) technology to upgrade + AF_INET TCP connections transparently. + The Linux implementation of the SMC-R solution is designed as + a separate socket family SMC. + + Select this option if you want to run SMC socket applications diff --git a/net/smc/Makefile b/net/smc/Makefile new file mode 100644 index 000000000000..c285c868dd82 --- /dev/null +++ b/net/smc/Makefile @@ -0,0 +1,2 @@ +obj-$(CONFIG_SMC) += smc.o +smc-y := af_smc.o diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c new file mode 100644 index 000000000000..7fd773fc6238 --- /dev/null +++ b/net/smc/af_smc.c @@ -0,0 +1,620 @@ +/* + * Shared Memory Communications over RDMA (SMC-R) and RoCE + * + * AF_SMC protocol family socket handler keeping the AF_INET sock address type + * applies to SOCK_STREAM sockets only + * offers an alternative communication option for TCP-protocol sockets + * applicable with RoCE-cards only + * + * Copyright IBM Corp. 2016 + * + * Author(s): Ursula Braun + * based on prototype from Frank Blaschka + */ + +#define KMSG_COMPONENT "smc" +#define pr_fmt(fmt) KMSG_COMPONENT ": " fmt + +#include +#include +#include + +#include "smc.h" + +static void smc_set_keepalive(struct sock *sk, int val) +{ + struct smc_sock *smc = smc_sk(sk); + + smc->clcsock->sk->sk_prot->keepalive(smc->clcsock->sk, val); +} + +static struct proto smc_proto = { + .name = "SMC", + .owner = THIS_MODULE, + .keepalive = smc_set_keepalive, + .obj_size = sizeof(struct smc_sock), + .slab_flags = SLAB_DESTROY_BY_RCU, +}; + +static int smc_release(struct socket *sock) +{ + struct sock *sk = sock->sk; + struct smc_sock *smc; + + if (!sk) + goto out; + + smc = smc_sk(sk); + lock_sock(sk); + + sk->sk_state = SMC_CLOSED; + if (smc->clcsock) { + sock_release(smc->clcsock); + smc->clcsock = NULL; + } + + /* detach socket */ + sock_orphan(sk); + sock->sk = NULL; + release_sock(sk); + + sock_put(sk); +out: + return 0; +} + +static void smc_destruct(struct sock *sk) +{ + if (sk->sk_state != SMC_CLOSED) + return; + if (!sock_flag(sk, SOCK_DEAD)) + return; + + sk_refcnt_debug_dec(sk); +} + +static struct sock *smc_sock_alloc(struct net *net, struct socket *sock) +{ + struct smc_sock *smc; + struct sock *sk; + + sk = sk_alloc(net, PF_SMC, GFP_KERNEL, &smc_proto, 0); + if (!sk) + return NULL; + + sock_init_data(sock, sk); /* sets sk_refcnt to 1 */ + sk->sk_state = SMC_INIT; + sk->sk_destruct = smc_destruct; + sk->sk_protocol = SMCPROTO_SMC; + sk_refcnt_debug_inc(sk); + + smc = smc_sk(sk); + + return sk; +} + +static int smc_bind(struct socket *sock, struct sockaddr *uaddr, + int addr_len) +{ + struct sockaddr_in *addr = (struct sockaddr_in *)uaddr; + struct sock *sk = sock->sk; + struct smc_sock *smc; + int rc; + + smc = smc_sk(sk); + + /* replicate tests from inet_bind(), to be safe wrt. future changes */ + rc = -EINVAL; + if (addr_len < sizeof(struct sockaddr_in)) + goto out; + + rc = -EAFNOSUPPORT; + /* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */ + if ((addr->sin_family != AF_INET) && + ((addr->sin_family != AF_UNSPEC) || + (addr->sin_addr.s_addr != htonl(INADDR_ANY)))) + goto out; + + lock_sock(sk); + + /* Check if socket is already active */ + rc = -EINVAL; + if (sk->sk_state != SMC_INIT) + goto out_rel; + + smc->clcsock->sk->sk_reuse = sk->sk_reuse; + rc = kernel_bind(smc->clcsock, uaddr, addr_len); + +out_rel: + release_sock(sk); +out: + return rc; +} + +static void smc_copy_sock_settings(struct sock *nsk, struct sock *osk, + unsigned long mask) +{ + /* options we don't get control via setsockopt for */ + nsk->sk_type = osk->sk_type; + nsk->sk_sndbuf = osk->sk_sndbuf; + nsk->sk_rcvbuf = osk->sk_rcvbuf; + nsk->sk_sndtimeo = osk->sk_sndtimeo; + nsk->sk_rcvtimeo = osk->sk_rcvtimeo; + nsk->sk_mark = osk->sk_mark; + nsk->sk_priority = osk->sk_priority; + nsk->sk_rcvlowat = osk->sk_rcvlowat; + nsk->sk_bound_dev_if = osk->sk_bound_dev_if; + nsk->sk_err = osk->sk_err; + + nsk->sk_flags &= ~mask; + nsk->sk_flags |= osk->sk_flags & mask; +} + +#define SK_FLAGS_SMC_TO_CLC ((1UL << SOCK_URGINLINE) | \ + (1UL << SOCK_KEEPOPEN) | \ + (1UL << SOCK_LINGER) | \ + (1UL << SOCK_BROADCAST) | \ + (1UL << SOCK_TIMESTAMP) | \ + (1UL << SOCK_DBG) | \ + (1UL << SOCK_RCVTSTAMP) | \ + (1UL << SOCK_RCVTSTAMPNS) | \ + (1UL << SOCK_LOCALROUTE) | \ + (1UL << SOCK_TIMESTAMPING_RX_SOFTWARE) | \ + (1UL << SOCK_RXQ_OVFL) | \ + (1UL << SOCK_WIFI_STATUS) | \ + (1UL << SOCK_NOFCS) | \ + (1UL << SOCK_FILTER_LOCKED)) +/* copy only relevant settings and flags of SOL_SOCKET level from smc to + * clc socket (since smc is not called for these options from net/core) + */ +static void smc_copy_sock_settings_to_clc(struct smc_sock *smc) +{ + smc_copy_sock_settings(smc->clcsock->sk, &smc->sk, SK_FLAGS_SMC_TO_CLC); +} + +#define SK_FLAGS_CLC_TO_SMC ((1UL << SOCK_URGINLINE) | \ + (1UL << SOCK_KEEPOPEN) | \ + (1UL << SOCK_LINGER) | \ + (1UL << SOCK_DBG)) +/* copy only settings and flags relevant for smc from clc to smc socket */ +static void smc_copy_sock_settings_to_smc(struct smc_sock *smc) +{ + smc_copy_sock_settings(&smc->sk, smc->clcsock->sk, SK_FLAGS_CLC_TO_SMC); +} + +static int smc_connect(struct socket *sock, struct sockaddr *addr, + int alen, int flags) +{ + struct sock *sk = sock->sk; + struct smc_sock *smc; + int rc = -EINVAL; + + smc = smc_sk(sk); + + /* separate smc parameter checking to be safe */ + if (alen < sizeof(addr->sa_family)) + goto out_err; + if (addr->sa_family != AF_INET) + goto out_err; + + lock_sock(sk); + switch (sk->sk_state) { + default: + goto out; + case SMC_ACTIVE: + rc = -EISCONN; + goto out; + case SMC_INIT: + rc = 0; + break; + } + + smc_copy_sock_settings_to_clc(smc); + rc = kernel_connect(smc->clcsock, addr, alen, flags); + if (rc) + goto out; + + sk->sk_state = SMC_ACTIVE; + + /* always use TCP fallback as transport mechanism for now; + * This will change once RDMA transport is implemented + */ + smc->use_fallback = true; + +out: + release_sock(sk); +out_err: + return rc; +} + +static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc) +{ + struct sock *sk = &lsmc->sk; + struct socket *new_clcsock; + struct sock *new_sk; + int rc; + + new_sk = smc_sock_alloc(sock_net(sk), NULL); + if (!new_sk) { + rc = -ENOMEM; + lsmc->sk.sk_err = ENOMEM; + *new_smc = NULL; + goto out; + } + *new_smc = smc_sk(new_sk); + + rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0); + if (rc) { + sock_put(new_sk); + *new_smc = NULL; + goto out; + } + + (*new_smc)->clcsock = new_clcsock; +out: + return rc; +} + +static int smc_listen(struct socket *sock, int backlog) +{ + struct sock *sk = sock->sk; + struct smc_sock *smc; + int rc; + + smc = smc_sk(sk); + lock_sock(sk); + + rc = -EINVAL; + if ((sk->sk_state != SMC_INIT) && (sk->sk_state != SMC_LISTEN)) + goto out; + + rc = 0; + if (sk->sk_state == SMC_LISTEN) { + sk->sk_max_ack_backlog = backlog; + goto out; + } + /* some socket options are handled in core, so we could not apply + * them to the clc socket -- copy smc socket options to clc socket + */ + smc_copy_sock_settings_to_clc(smc); + + rc = kernel_listen(smc->clcsock, backlog); + if (rc) + goto out; + sk->sk_max_ack_backlog = backlog; + sk->sk_ack_backlog = 0; + sk->sk_state = SMC_LISTEN; + +out: + release_sock(sk); + return rc; +} + +static int smc_accept(struct socket *sock, struct socket *new_sock, + int flags) +{ + struct smc_sock *new_smc; + struct sock *sk = sock->sk; + struct smc_sock *lsmc; + int rc; + + lsmc = smc_sk(sk); + lock_sock(sk); + + if (lsmc->sk.sk_state != SMC_LISTEN) { + rc = -EINVAL; + goto out; + } + + rc = smc_clcsock_accept(lsmc, &new_smc); + if (rc) + goto out; + sock_graft(&new_smc->sk, new_sock); + new_smc->sk.sk_state = SMC_ACTIVE; + + smc_copy_sock_settings_to_smc(new_smc); + + /* always use TCP fallback as transport mechanism for now; + * This will change once RDMA transport is implemented + */ + new_smc->use_fallback = true; + +out: + release_sock(sk); + return rc; +} + +static int smc_getname(struct socket *sock, struct sockaddr *addr, + int *len, int peer) +{ + struct smc_sock *smc; + + if (peer && (sock->sk->sk_state != SMC_ACTIVE)) + return -ENOTCONN; + + smc = smc_sk(sock->sk); + + return smc->clcsock->ops->getname(smc->clcsock, addr, len, peer); +} + +static int smc_sendmsg(struct socket *sock, struct msghdr *msg, size_t len) +{ + struct sock *sk = sock->sk; + struct smc_sock *smc; + int rc = -EPIPE; + + smc = smc_sk(sk); + lock_sock(sk); + if (sk->sk_state != SMC_ACTIVE) + goto out; + if (smc->use_fallback) + rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len); + else + rc = sock_no_sendmsg(sock, msg, len); +out: + release_sock(sk); + return rc; +} + +static int smc_recvmsg(struct socket *sock, struct msghdr *msg, size_t len, + int flags) +{ + struct sock *sk = sock->sk; + struct smc_sock *smc; + int rc = -ENOTCONN; + + smc = smc_sk(sk); + lock_sock(sk); + if ((sk->sk_state != SMC_ACTIVE) && (sk->sk_state != SMC_CLOSED)) + goto out; + + if (smc->use_fallback) + rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags); + else + rc = sock_no_recvmsg(sock, msg, len, flags); +out: + release_sock(sk); + return rc; +} + +static unsigned int smc_poll(struct file *file, struct socket *sock, + poll_table *wait) +{ + struct sock *sk = sock->sk; + unsigned int mask = 0; + struct smc_sock *smc; + + smc = smc_sk(sock->sk); + if ((sk->sk_state == SMC_INIT) || (sk->sk_state == SMC_LISTEN) || + smc->use_fallback) { + mask = smc->clcsock->ops->poll(file, smc->clcsock, wait); + /* if non-blocking connect finished ... */ + lock_sock(sk); + if ((sk->sk_state == SMC_INIT) && (mask & POLLOUT)) { + sk->sk_state = SMC_ACTIVE; + /* always use TCP fallback as transport mechanism; + * This will change once RDMA transport is implemented + */ + smc->use_fallback = true; + } + release_sock(sk); + } else { + mask = sock_no_poll(file, sock, wait); + } + + return mask; +} + +static int smc_shutdown(struct socket *sock, int how) +{ + struct sock *sk = sock->sk; + struct smc_sock *smc; + int rc = -EINVAL; + + smc = smc_sk(sk); + + if ((how < SHUT_RD) || (how > SHUT_RDWR)) + goto out_err; + + lock_sock(sk); + + rc = -ENOTCONN; + if (sk->sk_state == SMC_CLOSED) + goto out; + if (smc->use_fallback) { + rc = kernel_sock_shutdown(smc->clcsock, how); + sk->sk_shutdown = smc->clcsock->sk->sk_shutdown; + if (sk->sk_shutdown == SHUTDOWN_MASK) + sk->sk_state = SMC_CLOSED; + } else { + rc = sock_no_shutdown(sock, how); + } + +out: + release_sock(sk); + +out_err: + return rc; +} + +static int smc_setsockopt(struct socket *sock, int level, int optname, + char __user *optval, unsigned int optlen) +{ + struct sock *sk = sock->sk; + struct smc_sock *smc; + + smc = smc_sk(sk); + + /* generic setsockopts reaching us here always apply to the + * CLC socket + */ + return smc->clcsock->ops->setsockopt(smc->clcsock, level, optname, + optval, optlen); +} + +static int smc_getsockopt(struct socket *sock, int level, int optname, + char __user *optval, int __user *optlen) +{ + struct smc_sock *smc; + + smc = smc_sk(sock->sk); + /* socket options apply to the CLC socket */ + return smc->clcsock->ops->getsockopt(smc->clcsock, level, optname, + optval, optlen); +} + +static int smc_ioctl(struct socket *sock, unsigned int cmd, + unsigned long arg) +{ + struct smc_sock *smc; + + smc = smc_sk(sock->sk); + if (smc->use_fallback) + return smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg); + else + return sock_no_ioctl(sock, cmd, arg); +} + +static ssize_t smc_sendpage(struct socket *sock, struct page *page, + int offset, size_t size, int flags) +{ + struct sock *sk = sock->sk; + struct smc_sock *smc; + int rc = -EPIPE; + + smc = smc_sk(sk); + lock_sock(sk); + if (sk->sk_state != SMC_ACTIVE) + goto out; + if (smc->use_fallback) + rc = kernel_sendpage(smc->clcsock, page, offset, + size, flags); + else + rc = sock_no_sendpage(sock, page, offset, size, flags); + +out: + release_sock(sk); + return rc; +} + +static ssize_t smc_splice_read(struct socket *sock, loff_t *ppos, + struct pipe_inode_info *pipe, size_t len, + unsigned int flags) +{ + struct sock *sk = sock->sk; + struct smc_sock *smc; + int rc = -ENOTCONN; + + smc = smc_sk(sk); + lock_sock(sk); + if ((sk->sk_state != SMC_ACTIVE) && (sk->sk_state != SMC_CLOSED)) + goto out; + if (smc->use_fallback) { + rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos, + pipe, len, flags); + } else { + rc = -EOPNOTSUPP; + } +out: + release_sock(sk); + return rc; +} + +/* must look like tcp */ +static const struct proto_ops smc_sock_ops = { + .family = PF_SMC, + .owner = THIS_MODULE, + .release = smc_release, + .bind = smc_bind, + .connect = smc_connect, + .socketpair = sock_no_socketpair, + .accept = smc_accept, + .getname = smc_getname, + .poll = smc_poll, + .ioctl = smc_ioctl, + .listen = smc_listen, + .shutdown = smc_shutdown, + .setsockopt = smc_setsockopt, + .getsockopt = smc_getsockopt, + .sendmsg = smc_sendmsg, + .recvmsg = smc_recvmsg, + .mmap = sock_no_mmap, + .sendpage = smc_sendpage, + .splice_read = smc_splice_read, +}; + +static int smc_create(struct net *net, struct socket *sock, int protocol, + int kern) +{ + struct smc_sock *smc; + struct sock *sk; + int rc; + + rc = -ESOCKTNOSUPPORT; + if (sock->type != SOCK_STREAM) + goto out; + + rc = -EPROTONOSUPPORT; + if ((protocol != IPPROTO_IP) && (protocol != IPPROTO_TCP)) + goto out; + + rc = -ENOBUFS; + sock->ops = &smc_sock_ops; + sk = smc_sock_alloc(net, sock); + if (!sk) + goto out; + + /* create internal TCP socket for CLC handshake and fallback */ + smc = smc_sk(sk); + rc = sock_create_kern(net, PF_INET, SOCK_STREAM, + IPPROTO_TCP, &smc->clcsock); + if (rc) + sk_common_release(sk); + +out: + return rc; +} + +static const struct net_proto_family smc_sock_family_ops = { + .family = PF_SMC, + .owner = THIS_MODULE, + .create = smc_create, +}; + +static int __init smc_init(void) +{ + int rc; + + rc = proto_register(&smc_proto, 1); + if (rc) { + pr_err("%s: proto_register fails with %d\n", __func__, rc); + goto out; + } + + rc = sock_register(&smc_sock_family_ops); + if (rc) { + pr_err("%s: sock_register fails with %d\n", __func__, rc); + goto out_proto; + } + + return 0; + +out_proto: + proto_unregister(&smc_proto); +out: + return rc; +} + +static void __exit smc_exit(void) +{ + sock_unregister(PF_SMC); + proto_unregister(&smc_proto); +} + +module_init(smc_init); +module_exit(smc_exit); + +MODULE_AUTHOR("Ursula Braun "); +MODULE_DESCRIPTION("smc socket address family"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_NETPROTO(PF_SMC); diff --git a/net/smc/smc.h b/net/smc/smc.h new file mode 100644 index 000000000000..fcea7399e2eb --- /dev/null +++ b/net/smc/smc.h @@ -0,0 +1,37 @@ +/* + * Shared Memory Communications over RDMA (SMC-R) and RoCE + * + * Definitions for the SMC module (socket related) + * + * Copyright IBM Corp. 2016 + * + * Author(s): Ursula Braun + */ +#ifndef __SMC_H +#define __SMC_H + +#include +#include +#include + +#define SMCPROTO_SMC 0 /* SMC protocol */ + +enum smc_state { /* possible states of an SMC socket */ + SMC_ACTIVE = 1, + SMC_INIT = 2, + SMC_CLOSED = 7, + SMC_LISTEN = 10, +}; + +struct smc_sock { /* smc sock container */ + struct sock sk; + struct socket *clcsock; /* internal tcp socket */ + bool use_fallback; /* fallback to tcp */ +}; + +static inline struct smc_sock *smc_sk(const struct sock *sk) +{ + return (struct smc_sock *)sk; +} + +#endif /* __SMC_H */ -- cgit v1.2.3