/* * 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 * * Initial restrictions: * - support for alternate links postponed * - partial support for non-blocking sockets only * - support for urgent data postponed * * Copyright IBM Corp. 2016, 2018 * * 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 #include #include #include #include #include #include "smc.h" #include "smc_clc.h" #include "smc_llc.h" #include "smc_cdc.h" #include "smc_core.h" #include "smc_ib.h" #include "smc_pnet.h" #include "smc_tx.h" #include "smc_rx.h" #include "smc_close.h" static DEFINE_MUTEX(smc_create_lgr_pending); /* serialize link group * creation */ struct smc_lgr_list smc_lgr_list = { /* established link groups */ .lock = __SPIN_LOCK_UNLOCKED(smc_lgr_list.lock), .list = LIST_HEAD_INIT(smc_lgr_list.list), }; static void smc_tcp_listen_work(struct work_struct *); 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 smc_hashinfo smc_v4_hashinfo = { .lock = __RW_LOCK_UNLOCKED(smc_v4_hashinfo.lock), }; static struct smc_hashinfo smc_v6_hashinfo = { .lock = __RW_LOCK_UNLOCKED(smc_v6_hashinfo.lock), }; int smc_hash_sk(struct sock *sk) { struct smc_hashinfo *h = sk->sk_prot->h.smc_hash; struct hlist_head *head; head = &h->ht; write_lock_bh(&h->lock); sk_add_node(sk, head); sock_prot_inuse_add(sock_net(sk), sk->sk_prot, 1); write_unlock_bh(&h->lock); return 0; } EXPORT_SYMBOL_GPL(smc_hash_sk); void smc_unhash_sk(struct sock *sk) { struct smc_hashinfo *h = sk->sk_prot->h.smc_hash; write_lock_bh(&h->lock); if (sk_del_node_init(sk)) sock_prot_inuse_add(sock_net(sk), sk->sk_prot, -1); write_unlock_bh(&h->lock); } EXPORT_SYMBOL_GPL(smc_unhash_sk); struct proto smc_proto = { .name = "SMC", .owner = THIS_MODULE, .keepalive = smc_set_keepalive, .hash = smc_hash_sk, .unhash = smc_unhash_sk, .obj_size = sizeof(struct smc_sock), .h.smc_hash = &smc_v4_hashinfo, .slab_flags = SLAB_TYPESAFE_BY_RCU, }; EXPORT_SYMBOL_GPL(smc_proto); struct proto smc_proto6 = { .name = "SMC6", .owner = THIS_MODULE, .keepalive = smc_set_keepalive, .hash = smc_hash_sk, .unhash = smc_unhash_sk, .obj_size = sizeof(struct smc_sock), .h.smc_hash = &smc_v6_hashinfo, .slab_flags = SLAB_TYPESAFE_BY_RCU, }; EXPORT_SYMBOL_GPL(smc_proto6); static int smc_release(struct socket *sock) { struct sock *sk = sock->sk; struct smc_sock *smc; int rc = 0; if (!sk) goto out; smc = smc_sk(sk); if (sk->sk_state == SMC_LISTEN) /* smc_close_non_accepted() is called and acquires * sock lock for child sockets again */ lock_sock_nested(sk, SINGLE_DEPTH_NESTING); else lock_sock(sk); if (!smc->use_fallback) { rc = smc_close_active(smc); sock_set_flag(sk, SOCK_DEAD); sk->sk_shutdown |= SHUTDOWN_MASK; } if (smc->clcsock) { sock_release(smc->clcsock); smc->clcsock = NULL; } if (smc->use_fallback) { sock_put(sk); /* passive closing */ sk->sk_state = SMC_CLOSED; sk->sk_state_change(sk); } /* detach socket */ sock_orphan(sk); sock->sk = NULL; if (!smc->use_fallback && sk->sk_state == SMC_CLOSED) smc_conn_free(&smc->conn); release_sock(sk); sk->sk_prot->unhash(sk); sock_put(sk); /* final sock_put */ out: return rc; } 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, int protocol) { struct smc_sock *smc; struct proto *prot; struct sock *sk; prot = (protocol == SMCPROTO_SMC6) ? &smc_proto6 : &smc_proto; sk = sk_alloc(net, PF_SMC, GFP_KERNEL, prot, 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 = protocol; smc = smc_sk(sk); INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work); INIT_LIST_HEAD(&smc->accept_q); spin_lock_init(&smc->accept_q_lock); sk->sk_prot->hash(sk); sk_refcnt_debug_inc(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; if (addr->sin_family != AF_INET && addr->sin_family != AF_INET6 && addr->sin_family != AF_UNSPEC) goto out; /* accept AF_UNSPEC (mapped to AF_INET) only if s_addr is INADDR_ANY */ if (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); } /* register a new rmb, optionally send confirm_rkey msg to register with peer */ static int smc_reg_rmb(struct smc_link *link, struct smc_buf_desc *rmb_desc, bool conf_rkey) { /* register memory region for new rmb */ if (smc_wr_reg_send(link, rmb_desc->mr_rx[SMC_SINGLE_LINK])) { rmb_desc->regerr = 1; return -EFAULT; } if (!conf_rkey) return 0; /* exchange confirm_rkey msg with peer */ if (smc_llc_do_confirm_rkey(link, rmb_desc)) { rmb_desc->regerr = 1; return -EFAULT; } return 0; } static int smc_clnt_conf_first_link(struct smc_sock *smc) { struct net *net = sock_net(smc->clcsock->sk); struct smc_link_group *lgr = smc->conn.lgr; struct smc_link *link; int rest; int rc; link = &lgr->lnk[SMC_SINGLE_LINK]; /* receive CONFIRM LINK request from server over RoCE fabric */ rest = wait_for_completion_interruptible_timeout( &link->llc_confirm, SMC_LLC_WAIT_FIRST_TIME); if (rest <= 0) { struct smc_clc_msg_decline dclc; rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc), SMC_CLC_DECLINE); return rc; } if (link->llc_confirm_rc) return SMC_CLC_DECL_RMBE_EC; rc = smc_ib_modify_qp_rts(link); if (rc) return SMC_CLC_DECL_INTERR; smc_wr_remember_qp_attr(link); if (smc_reg_rmb(link, smc->conn.rmb_desc, false)) return SMC_CLC_DECL_INTERR; /* send CONFIRM LINK response over RoCE fabric */ rc = smc_llc_send_confirm_link(link, link->smcibdev->mac[link->ibport - 1], &link->smcibdev->gid[link->ibport - 1], SMC_LLC_RESP); if (rc < 0) return SMC_CLC_DECL_TCL; /* receive ADD LINK request from server over RoCE fabric */ rest = wait_for_completion_interruptible_timeout(&link->llc_add, SMC_LLC_WAIT_TIME); if (rest <= 0) { struct smc_clc_msg_decline dclc; rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc), SMC_CLC_DECLINE); return rc; } /* send add link reject message, only one link supported for now */ rc = smc_llc_send_add_link(link, link->smcibdev->mac[link->ibport - 1], &link->smcibdev->gid[link->ibport - 1], SMC_LLC_RESP); if (rc < 0) return SMC_CLC_DECL_TCL; smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time); return 0; } static void smc_conn_save_peer_info(struct smc_sock *smc, struct smc_clc_msg_accept_confirm *clc) { smc->conn.peer_conn_idx = clc->conn_idx; smc->conn.local_tx_ctrl.token = ntohl(clc->rmbe_alert_token); smc->conn.peer_rmbe_size = smc_uncompress_bufsize(clc->rmbe_size); atomic_set(&smc->conn.peer_rmbe_space, smc->conn.peer_rmbe_size); } static void smc_link_save_peer_info(struct smc_link *link, struct smc_clc_msg_accept_confirm *clc) { link->peer_qpn = ntoh24(clc->qpn); memcpy(link->peer_gid, clc->lcl.gid, SMC_GID_SIZE); memcpy(link->peer_mac, clc->lcl.mac, sizeof(link->peer_mac)); link->peer_psn = ntoh24(clc->psn); link->peer_mtu = clc->qp_mtu; } /* setup for RDMA connection of client */ static int smc_connect_rdma(struct smc_sock *smc) { struct smc_clc_msg_accept_confirm aclc; int local_contact = SMC_FIRST_CONTACT; struct smc_ib_device *smcibdev; struct smc_link *link; u8 srv_first_contact; int reason_code = 0; int rc = 0; u8 ibport; sock_hold(&smc->sk); /* sock put in passive closing */ if (smc->use_fallback) goto out_connected; if (!tcp_sk(smc->clcsock->sk)->syn_smc) { /* peer has not signalled SMC-capability */ smc->use_fallback = true; goto out_connected; } /* IPSec connections opt out of SMC-R optimizations */ if (using_ipsec(smc)) { reason_code = SMC_CLC_DECL_IPSEC; goto decline_rdma; } /* PNET table look up: search active ib_device and port * within same PNETID that also contains the ethernet device * used for the internal TCP socket */ smc_pnet_find_roce_resource(smc->clcsock->sk, &smcibdev, &ibport); if (!smcibdev) { reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */ goto decline_rdma; } /* do inband token exchange */ reason_code = smc_clc_send_proposal(smc, smcibdev, ibport); if (reason_code < 0) { rc = reason_code; goto out_err; } if (reason_code > 0) /* configuration error */ goto decline_rdma; /* receive SMC Accept CLC message */ reason_code = smc_clc_wait_msg(smc, &aclc, sizeof(aclc), SMC_CLC_ACCEPT); if (reason_code < 0) { rc = reason_code; goto out_err; } if (reason_code > 0) goto decline_rdma; srv_first_contact = aclc.hdr.flag; mutex_lock(&smc_create_lgr_pending); local_contact = smc_conn_create(smc, smcibdev, ibport, &aclc.lcl, srv_first_contact); if (local_contact < 0) { rc = local_contact; if (rc == -ENOMEM) reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/ else if (rc == -ENOLINK) reason_code = SMC_CLC_DECL_SYNCERR; /* synchr. error */ else reason_code = SMC_CLC_DECL_INTERR; /* other error */ goto decline_rdma_unlock; } link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK]; smc_conn_save_peer_info(smc, &aclc); /* create send buffer and rmb */ rc = smc_buf_create(smc); if (rc) { reason_code = SMC_CLC_DECL_MEM; goto decline_rdma_unlock; } if (local_contact == SMC_FIRST_CONTACT) smc_link_save_peer_info(link, &aclc); rc = smc_rmb_rtoken_handling(&smc->conn, &aclc); if (rc) { reason_code = SMC_CLC_DECL_INTERR; goto decline_rdma_unlock; } smc_close_init(smc); smc_rx_init(smc); if (local_contact == SMC_FIRST_CONTACT) { rc = smc_ib_ready_link(link); if (rc) { reason_code = SMC_CLC_DECL_INTERR; goto decline_rdma_unlock; } } else { if (!smc->conn.rmb_desc->reused) { if (smc_reg_rmb(link, smc->conn.rmb_desc, true)) { reason_code = SMC_CLC_DECL_INTERR; goto decline_rdma_unlock; } } } smc_rmb_sync_sg_for_device(&smc->conn); rc = smc_clc_send_confirm(smc); if (rc) goto out_err_unlock; if (local_contact == SMC_FIRST_CONTACT) { /* QP confirmation over RoCE fabric */ reason_code = smc_clnt_conf_first_link(smc); if (reason_code < 0) { rc = reason_code; goto out_err_unlock; } if (reason_code > 0) goto decline_rdma_unlock; } mutex_unlock(&smc_create_lgr_pending); smc_tx_init(smc); out_connected: smc_copy_sock_settings_to_clc(smc); if (smc->sk.sk_state == SMC_INIT) smc->sk.sk_state = SMC_ACTIVE; return rc ? rc : local_contact; decline_rdma_unlock: if (local_contact == SMC_FIRST_CONTACT) smc_lgr_forget(smc->conn.lgr); mutex_unlock(&smc_create_lgr_pending); smc_conn_free(&smc->conn); decline_rdma: /* RDMA setup failed, switch back to TCP */ smc->use_fallback = true; if (reason_code && (reason_code != SMC_CLC_DECL_REPLY)) { rc = smc_clc_send_decline(smc, reason_code); if (rc < 0) goto out_err; } goto out_connected; out_err_unlock: if (local_contact == SMC_FIRST_CONTACT) smc_lgr_forget(smc->conn.lgr); mutex_unlock(&smc_create_lgr_pending); smc_conn_free(&smc->conn); out_err: if (smc->sk.sk_state == SMC_INIT) sock_put(&smc->sk); /* passive closing */ return rc; } 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 && addr->sa_family != AF_INET6) 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); tcp_sk(smc->clcsock->sk)->syn_smc = 1; rc = kernel_connect(smc->clcsock, addr, alen, flags); if (rc) goto out; /* setup RDMA connection */ rc = smc_connect_rdma(smc); if (rc < 0) goto out; else rc = 0; /* success cases including fallback */ out: release_sock(sk); out_err: return rc; } static int smc_clcsock_accept(struct smc_sock *lsmc, struct smc_sock **new_smc) { struct socket *new_clcsock = NULL; struct sock *lsk = &lsmc->sk; struct sock *new_sk; int rc; release_sock(lsk); new_sk = smc_sock_alloc(sock_net(lsk), NULL, lsk->sk_protocol); if (!new_sk) { rc = -ENOMEM; lsk->sk_err = ENOMEM; *new_smc = NULL; lock_sock(lsk); goto out; } *new_smc = smc_sk(new_sk); rc = kernel_accept(lsmc->clcsock, &new_clcsock, 0); lock_sock(lsk); if (rc < 0) lsk->sk_err = -rc; if (rc < 0 || lsk->sk_state == SMC_CLOSED) { if (new_clcsock) sock_release(new_clcsock); new_sk->sk_state = SMC_CLOSED; sock_set_flag(new_sk, SOCK_DEAD); new_sk->sk_prot->unhash(new_sk); sock_put(new_sk); /* final */ *new_smc = NULL; goto out; } (*new_smc)->clcsock = new_clcsock; out: return rc; } /* add a just created sock to the accept queue of the listen sock as * candidate for a following socket accept call from user space */ static void smc_accept_enqueue(struct sock *parent, struct sock *sk) { struct smc_sock *par = smc_sk(parent); sock_hold(sk); /* sock_put in smc_accept_unlink () */ spin_lock(&par->accept_q_lock); list_add_tail(&smc_sk(sk)->accept_q, &par->accept_q); spin_unlock(&par->accept_q_lock); sk_acceptq_added(parent); } /* remove a socket from the accept queue of its parental listening socket */ static void smc_accept_unlink(struct sock *sk) { struct smc_sock *par = smc_sk(sk)->listen_smc; spin_lock(&par->accept_q_lock); list_del_init(&smc_sk(sk)->accept_q); spin_unlock(&par->accept_q_lock); sk_acceptq_removed(&smc_sk(sk)->listen_smc->sk); sock_put(sk); /* sock_hold in smc_accept_enqueue */ } /* remove a sock from the accept queue to bind it to a new socket created * for a socket accept call from user space */ struct sock *smc_accept_dequeue(struct sock *parent, struct socket *new_sock) { struct smc_sock *isk, *n; struct sock *new_sk; list_for_each_entry_safe(isk, n, &smc_sk(parent)->accept_q, accept_q) { new_sk = (struct sock *)isk; smc_accept_unlink(new_sk); if (new_sk->sk_state == SMC_CLOSED) { if (isk->clcsock) { sock_release(isk->clcsock); isk->clcsock = NULL; } new_sk->sk_prot->unhash(new_sk); sock_put(new_sk); /* final */ continue; } if (new_sock) sock_graft(new_sk, new_sock); return new_sk; } return NULL; } /* clean up for a created but never accepted sock */ void smc_close_non_accepted(struct sock *sk) { struct smc_sock *smc = smc_sk(sk); lock_sock(sk); if (!sk->sk_lingertime) /* wait for peer closing */ sk->sk_lingertime = SMC_MAX_STREAM_WAIT_TIMEOUT; if (!smc->use_fallback) { smc_close_active(smc); sock_set_flag(sk, SOCK_DEAD); sk->sk_shutdown |= SHUTDOWN_MASK; } if (smc->clcsock) { struct socket *tcp; tcp = smc->clcsock; smc->clcsock = NULL; sock_release(tcp); } if (smc->use_fallback) { sock_put(sk); /* passive closing */ sk->sk_state = SMC_CLOSED; } else { if (sk->sk_state == SMC_CLOSED) smc_conn_free(&smc->conn); } release_sock(sk); sk->sk_prot->unhash(sk); sock_put(sk); /* final sock_put */ } static int smc_serv_conf_first_link(struct smc_sock *smc) { struct net *net = sock_net(smc->clcsock->sk); struct smc_link_group *lgr = smc->conn.lgr; struct smc_link *link; int rest; int rc; link = &lgr->lnk[SMC_SINGLE_LINK]; if (smc_reg_rmb(link, smc->conn.rmb_desc, false)) return SMC_CLC_DECL_INTERR; /* send CONFIRM LINK request to client over the RoCE fabric */ rc = smc_llc_send_confirm_link(link, link->smcibdev->mac[link->ibport - 1], &link->smcibdev->gid[link->ibport - 1], SMC_LLC_REQ); if (rc < 0) return SMC_CLC_DECL_TCL; /* receive CONFIRM LINK response from client over the RoCE fabric */ rest = wait_for_completion_interruptible_timeout( &link->llc_confirm_resp, SMC_LLC_WAIT_FIRST_TIME); if (rest <= 0) { struct smc_clc_msg_decline dclc; rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc), SMC_CLC_DECLINE); return rc; } if (link->llc_confirm_resp_rc) return SMC_CLC_DECL_RMBE_EC; /* send ADD LINK request to client over the RoCE fabric */ rc = smc_llc_send_add_link(link, link->smcibdev->mac[link->ibport - 1], &link->smcibdev->gid[link->ibport - 1], SMC_LLC_REQ); if (rc < 0) return SMC_CLC_DECL_TCL; /* receive ADD LINK response from client over the RoCE fabric */ rest = wait_for_completion_interruptible_timeout(&link->llc_add_resp, SMC_LLC_WAIT_TIME); if (rest <= 0) { struct smc_clc_msg_decline dclc; rc = smc_clc_wait_msg(smc, &dclc, sizeof(dclc), SMC_CLC_DECLINE); return rc; } smc_llc_link_active(link, net->ipv4.sysctl_tcp_keepalive_time); return 0; } /* setup for RDMA connection of server */ static void smc_listen_work(struct work_struct *work) { struct smc_sock *new_smc = container_of(work, struct smc_sock, smc_listen_work); struct smc_clc_msg_proposal_prefix *pclc_prfx; struct socket *newclcsock = new_smc->clcsock; struct smc_sock *lsmc = new_smc->listen_smc; struct smc_clc_msg_accept_confirm cclc; int local_contact = SMC_REUSE_CONTACT; struct sock *newsmcsk = &new_smc->sk; struct smc_clc_msg_proposal *pclc; struct smc_ib_device *smcibdev; u8 buf[SMC_CLC_MAX_LEN]; struct smc_link *link; int reason_code = 0; int rc = 0; u8 ibport; if (new_smc->use_fallback) goto out_connected; /* check if peer is smc capable */ if (!tcp_sk(newclcsock->sk)->syn_smc) { new_smc->use_fallback = true; goto out_connected; } /* do inband token exchange - *wait for and receive SMC Proposal CLC message */ reason_code = smc_clc_wait_msg(new_smc, &buf, sizeof(buf), SMC_CLC_PROPOSAL); if (reason_code < 0) goto out_err; if (reason_code > 0) goto decline_rdma; /* IPSec connections opt out of SMC-R optimizations */ if (using_ipsec(new_smc)) { reason_code = SMC_CLC_DECL_IPSEC; goto decline_rdma; } /* PNET table look up: search active ib_device and port * within same PNETID that also contains the ethernet device * used for the internal TCP socket */ smc_pnet_find_roce_resource(newclcsock->sk, &smcibdev, &ibport); if (!smcibdev) { reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */ goto decline_rdma; } pclc = (struct smc_clc_msg_proposal *)&buf; pclc_prfx = smc_clc_proposal_get_prefix(pclc); rc = smc_clc_prfx_match(newclcsock, pclc_prfx); if (rc) { reason_code = SMC_CLC_DECL_CNFERR; /* configuration error */ goto decline_rdma; } /* allocate connection / link group */ mutex_lock(&smc_create_lgr_pending); local_contact = smc_conn_create(new_smc, smcibdev, ibport, &pclc->lcl, 0); if (local_contact < 0) { rc = local_contact; if (rc == -ENOMEM) reason_code = SMC_CLC_DECL_MEM;/* insufficient memory*/ goto decline_rdma_unlock; } link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK]; /* create send buffer and rmb */ rc = smc_buf_create(new_smc); if (rc) { reason_code = SMC_CLC_DECL_MEM; goto decline_rdma_unlock; } smc_close_init(new_smc); smc_rx_init(new_smc); if (local_contact != SMC_FIRST_CONTACT) { if (!new_smc->conn.rmb_desc->reused) { if (smc_reg_rmb(link, new_smc->conn.rmb_desc, true)) { reason_code = SMC_CLC_DECL_INTERR; goto decline_rdma_unlock; } } } smc_rmb_sync_sg_for_device(&new_smc->conn); rc = smc_clc_send_accept(new_smc, local_contact); if (rc) goto out_err_unlock; /* receive SMC Confirm CLC message */ reason_code = smc_clc_wait_msg(new_smc, &cclc, sizeof(cclc), SMC_CLC_CONFIRM); if (reason_code < 0) goto out_err_unlock; if (reason_code > 0) goto decline_rdma_unlock; smc_conn_save_peer_info(new_smc, &cclc); if (local_contact == SMC_FIRST_CONTACT) smc_link_save_peer_info(link, &cclc); rc = smc_rmb_rtoken_handling(&new_smc->conn, &cclc); if (rc) { reason_code = SMC_CLC_DECL_INTERR; goto decline_rdma_unlock; } if (local_contact == SMC_FIRST_CONTACT) { rc = smc_ib_ready_link(link); if (rc) { reason_code = SMC_CLC_DECL_INTERR; goto decline_rdma_unlock; } /* QP confirmation over RoCE fabric */ reason_code = smc_serv_conf_first_link(new_smc); if (reason_code < 0) /* peer is not aware of a problem */ goto out_err_unlock; if (reason_code > 0) goto decline_rdma_unlock; } smc_tx_init(new_smc); mutex_unlock(&smc_create_lgr_pending); out_connected: sk_refcnt_debug_inc(newsmcsk); if (newsmcsk->sk_state == SMC_INIT) newsmcsk->sk_state = SMC_ACTIVE; enqueue: lock_sock_nested(&lsmc->sk, SINGLE_DEPTH_NESTING); if (lsmc->sk.sk_state == SMC_LISTEN) { smc_accept_enqueue(&lsmc->sk, newsmcsk); } else { /* no longer listening */ smc_close_non_accepted(newsmcsk); } release_sock(&lsmc->sk); /* Wake up accept */ lsmc->sk.sk_data_ready(&lsmc->sk); sock_put(&lsmc->sk); /* sock_hold in smc_tcp_listen_work */ return; decline_rdma_unlock: if (local_contact == SMC_FIRST_CONTACT) smc_lgr_forget(new_smc->conn.lgr); mutex_unlock(&smc_create_lgr_pending); decline_rdma: /* RDMA setup failed, switch back to TCP */ smc_conn_free(&new_smc->conn); new_smc->use_fallback = true; if (reason_code && (reason_code != SMC_CLC_DECL_REPLY)) { if (smc_clc_send_decline(new_smc, reason_code) < 0) goto out_err; } goto out_connected; out_err_unlock: if (local_contact == SMC_FIRST_CONTACT) smc_lgr_forget(new_smc->conn.lgr); mutex_unlock(&smc_create_lgr_pending); out_err: if (newsmcsk->sk_state == SMC_INIT) sock_put(&new_smc->sk); /* passive closing */ newsmcsk->sk_state = SMC_CLOSED; smc_conn_free(&new_smc->conn); goto enqueue; /* queue new sock with sk_err set */ } static void smc_tcp_listen_work(struct work_struct *work) { struct smc_sock *lsmc = container_of(work, struct smc_sock, tcp_listen_work); struct sock *lsk = &lsmc->sk; struct smc_sock *new_smc; int rc = 0; lock_sock(lsk); while (lsk->sk_state == SMC_LISTEN) { rc = smc_clcsock_accept(lsmc, &new_smc); if (rc) goto out; if (!new_smc) continue; new_smc->listen_smc = lsmc; new_smc->use_fallback = lsmc->use_fallback; sock_hold(lsk); /* sock_put in smc_listen_work */ INIT_WORK(&new_smc->smc_listen_work, smc_listen_work); smc_copy_sock_settings_to_smc(new_smc); sock_hold(&new_smc->sk); /* sock_put in passive closing */ if (!schedule_work(&new_smc->smc_listen_work)) sock_put(&new_smc->sk); } out: release_sock(lsk); sock_put(&lsmc->sk); /* sock_hold in smc_listen */ } 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); if (!smc->use_fallback) tcp_sk(smc->clcsock->sk)->syn_smc = 1; 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; INIT_WORK(&smc->tcp_listen_work, smc_tcp_listen_work); sock_hold(sk); /* sock_hold in tcp_listen_worker */ if (!schedule_work(&smc->tcp_listen_work)) sock_put(sk); out: release_sock(sk); return rc; } static int smc_accept(struct socket *sock, struct socket *new_sock, int flags, bool kern) { struct sock *sk = sock->sk, *nsk; DECLARE_WAITQUEUE(wait, current); struct smc_sock *lsmc; long timeo; int rc = 0; lsmc = smc_sk(sk); sock_hold(sk); /* sock_put below */ lock_sock(sk); if (lsmc->sk.sk_state != SMC_LISTEN) { rc = -EINVAL; release_sock(sk); goto out; } /* Wait for an incoming connection */ timeo = sock_rcvtimeo(sk, flags & O_NONBLOCK); add_wait_queue_exclusive(sk_sleep(sk), &wait); while (!(nsk = smc_accept_dequeue(sk, new_sock))) { set_current_state(TASK_INTERRUPTIBLE); if (!timeo) { rc = -EAGAIN; break; } release_sock(sk); timeo = schedule_timeout(timeo); /* wakeup by sk_data_ready in smc_listen_work() */ sched_annotate_sleep(); lock_sock(sk); if (signal_pending(current)) { rc = sock_intr_errno(timeo); break; } } set_current_state(TASK_RUNNING); remove_wait_queue(sk_sleep(sk), &wait); if (!rc) rc = sock_error(nsk); release_sock(sk); if (rc) goto out; if (lsmc->sockopt_defer_accept && !(flags & O_NONBLOCK)) { /* wait till data arrives on the socket */ timeo = msecs_to_jiffies(lsmc->sockopt_defer_accept * MSEC_PER_SEC); if (smc_sk(nsk)->use_fallback) { struct sock *clcsk = smc_sk(nsk)->clcsock->sk; lock_sock(clcsk); if (skb_queue_empty(&clcsk->sk_receive_queue)) sk_wait_data(clcsk, &timeo, NULL); release_sock(clcsk); } else if (!atomic_read(&smc_sk(nsk)->conn.bytes_to_rcv)) { lock_sock(nsk); smc_rx_wait(smc_sk(nsk), &timeo, smc_rx_data_available); release_sock(nsk); } } out: sock_put(sk); /* sock_hold above */ return rc; } static int smc_getname(struct socket *sock, struct sockaddr *addr, int peer) { struct smc_sock *smc; if (peer && (sock->sk->sk_state != SMC_ACTIVE) && (sock->sk->sk_state != SMC_APPCLOSEWAIT1)) return -ENOTCONN; smc = smc_sk(sock->sk); return smc->clcsock->ops->getname(smc->clcsock, addr, 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) && (sk->sk_state != SMC_APPCLOSEWAIT1) && (sk->sk_state != SMC_INIT)) goto out; if (msg->msg_flags & MSG_FASTOPEN) { if (sk->sk_state == SMC_INIT) { smc->use_fallback = true; } else { rc = -EINVAL; goto out; } } if (smc->use_fallback) rc = smc->clcsock->ops->sendmsg(smc->clcsock, msg, len); else rc = smc_tx_sendmsg(smc, 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_INIT) || (sk->sk_state == SMC_LISTEN) || (sk->sk_state == SMC_CLOSED)) goto out; if (sk->sk_state == SMC_PEERFINCLOSEWAIT) { rc = 0; goto out; } if (smc->use_fallback) { rc = smc->clcsock->ops->recvmsg(smc->clcsock, msg, len, flags); } else { msg->msg_namelen = 0; rc = smc_rx_recvmsg(smc, msg, NULL, len, flags); } out: release_sock(sk); return rc; } static __poll_t smc_accept_poll(struct sock *parent) { struct smc_sock *isk = smc_sk(parent); __poll_t mask = 0; spin_lock(&isk->accept_q_lock); if (!list_empty(&isk->accept_q)) mask = EPOLLIN | EPOLLRDNORM; spin_unlock(&isk->accept_q_lock); return mask; } static __poll_t smc_poll(struct file *file, struct socket *sock, poll_table *wait) { struct sock *sk = sock->sk; __poll_t mask = 0; struct smc_sock *smc; int rc; if (!sk) return EPOLLNVAL; smc = smc_sk(sock->sk); sock_hold(sk); lock_sock(sk); if ((sk->sk_state == SMC_INIT) || smc->use_fallback) { /* delegate to CLC child sock */ release_sock(sk); mask = smc->clcsock->ops->poll(file, smc->clcsock, wait); lock_sock(sk); sk->sk_err = smc->clcsock->sk->sk_err; if (sk->sk_err) { mask |= EPOLLERR; } else { /* if non-blocking connect finished ... */ if (sk->sk_state == SMC_INIT && mask & EPOLLOUT && smc->clcsock->sk->sk_state != TCP_CLOSE) { rc = smc_connect_rdma(smc); if (rc < 0) mask |= EPOLLERR; /* success cases including fallback */ mask |= EPOLLOUT | EPOLLWRNORM; } } } else { if (sk->sk_state != SMC_CLOSED) { release_sock(sk); sock_poll_wait(file, sk_sleep(sk), wait); lock_sock(sk); } if (sk->sk_err) mask |= EPOLLERR; if ((sk->sk_shutdown == SHUTDOWN_MASK) || (sk->sk_state == SMC_CLOSED)) mask |= EPOLLHUP; if (sk->sk_state == SMC_LISTEN) { /* woken up by sk_data_ready in smc_listen_work() */ mask = smc_accept_poll(sk); } else { if (atomic_read(&smc->conn.sndbuf_space) || sk->sk_shutdown & SEND_SHUTDOWN) { mask |= EPOLLOUT | EPOLLWRNORM; } else { sk_set_bit(SOCKWQ_ASYNC_NOSPACE, sk); set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); } if (atomic_read(&smc->conn.bytes_to_rcv)) mask |= EPOLLIN | EPOLLRDNORM; if (sk->sk_shutdown & RCV_SHUTDOWN) mask |= EPOLLIN | EPOLLRDNORM | EPOLLRDHUP; if (sk->sk_state == SMC_APPCLOSEWAIT1) mask |= EPOLLIN; } } release_sock(sk); sock_put(sk); return mask; } static int smc_shutdown(struct socket *sock, int how) { struct sock *sk = sock->sk; struct smc_sock *smc; int rc = -EINVAL; int rc1 = 0; smc = smc_sk(sk); if ((how < SHUT_RD) || (how > SHUT_RDWR)) return rc; lock_sock(sk); rc = -ENOTCONN; if ((sk->sk_state != SMC_LISTEN) && (sk->sk_state != SMC_ACTIVE) && (sk->sk_state != SMC_PEERCLOSEWAIT1) && (sk->sk_state != SMC_PEERCLOSEWAIT2) && (sk->sk_state != SMC_APPCLOSEWAIT1) && (sk->sk_state != SMC_APPCLOSEWAIT2) && (sk->sk_state != SMC_APPFINCLOSEWAIT)) 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; goto out; } switch (how) { case SHUT_RDWR: /* shutdown in both directions */ rc = smc_close_active(smc); break; case SHUT_WR: rc = smc_close_shutdown_write(smc); break; case SHUT_RD: rc = 0; /* nothing more to do because peer is not involved */ break; } if (smc->clcsock) rc1 = kernel_sock_shutdown(smc->clcsock, how); /* map sock_shutdown_cmd constants to sk_shutdown value range */ sk->sk_shutdown |= how + 1; out: release_sock(sk); return rc ? rc : rc1; } 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; int val, rc; smc = smc_sk(sk); /* generic setsockopts reaching us here always apply to the * CLC socket */ rc = smc->clcsock->ops->setsockopt(smc->clcsock, level, optname, optval, optlen); if (smc->clcsock->sk->sk_err) { sk->sk_err = smc->clcsock->sk->sk_err; sk->sk_error_report(sk); } if (rc) return rc; if (optlen < sizeof(int)) return rc; get_user(val, (int __user *)optval); lock_sock(sk); switch (optname) { case TCP_ULP: case TCP_FASTOPEN: case TCP_FASTOPEN_CONNECT: case TCP_FASTOPEN_KEY: case TCP_FASTOPEN_NO_COOKIE: /* option not supported by SMC */ if (sk->sk_state == SMC_INIT) { smc->use_fallback = true; } else { if (!smc->use_fallback) rc = -EINVAL; } break; case TCP_NODELAY: if (sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) { if (val && !smc->use_fallback) mod_delayed_work(system_wq, &smc->conn.tx_work, 0); } break; case TCP_CORK: if (sk->sk_state != SMC_INIT && sk->sk_state != SMC_LISTEN) { if (!val && !smc->use_fallback) mod_delayed_work(system_wq, &smc->conn.tx_work, 0); } break; case TCP_DEFER_ACCEPT: smc->sockopt_defer_accept = val; break; default: break; } release_sock(sk); return rc; } 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; int answ; smc = smc_sk(sock->sk); if (smc->use_fallback) { if (!smc->clcsock) return -EBADF; return smc->clcsock->ops->ioctl(smc->clcsock, cmd, arg); } switch (cmd) { case SIOCINQ: /* same as FIONREAD */ if (smc->sk.sk_state == SMC_LISTEN) return -EINVAL; answ = atomic_read(&smc->conn.bytes_to_rcv); break; case SIOCOUTQ: /* output queue size (not send + not acked) */ if (smc->sk.sk_state == SMC_LISTEN) return -EINVAL; answ = smc->conn.sndbuf_size - atomic_read(&smc->conn.sndbuf_space); break; case SIOCOUTQNSD: /* output queue size (not send only) */ if (smc->sk.sk_state == SMC_LISTEN) return -EINVAL; answ = smc_tx_prepared_sends(&smc->conn); break; default: return -ENOIOCTLCMD; } return put_user(answ, (int __user *)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) { release_sock(sk); goto out; } release_sock(sk); if (smc->use_fallback) rc = kernel_sendpage(smc->clcsock, page, offset, size, flags); else rc = sock_no_sendpage(sock, page, offset, size, flags); out: return rc; } /* Map the affected portions of the rmbe into an spd, note the number of bytes * to splice in conn->splice_pending, and press 'go'. Delays consumer cursor * updates till whenever a respective page has been fully processed. * Note that subsequent recv() calls have to wait till all splice() processing * completed. */ 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_INIT || sk->sk_state == SMC_LISTEN || sk->sk_state == SMC_CLOSED) goto out; if (sk->sk_state == SMC_PEERFINCLOSEWAIT) { rc = 0; goto out; } if (smc->use_fallback) { rc = smc->clcsock->ops->splice_read(smc->clcsock, ppos, pipe, len, flags); } else { if (*ppos) { rc = -ESPIPE; goto out; } if (flags & SPLICE_F_NONBLOCK) flags = MSG_DONTWAIT; else flags = 0; rc = smc_rx_recvmsg(smc, NULL, pipe, len, flags); } 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) { int family = (protocol == SMCPROTO_SMC6) ? PF_INET6 : PF_INET; struct smc_sock *smc; struct sock *sk; int rc; rc = -ESOCKTNOSUPPORT; if (sock->type != SOCK_STREAM) goto out; rc = -EPROTONOSUPPORT; if (protocol != SMCPROTO_SMC && protocol != SMCPROTO_SMC6) goto out; rc = -ENOBUFS; sock->ops = &smc_sock_ops; sk = smc_sock_alloc(net, sock, protocol); if (!sk) goto out; /* create internal TCP socket for CLC handshake and fallback */ smc = smc_sk(sk); smc->use_fallback = false; /* assume rdma capability first */ rc = sock_create_kern(net, family, SOCK_STREAM, IPPROTO_TCP, &smc->clcsock); if (rc) { sk_common_release(sk); goto out; } smc->sk.sk_sndbuf = max(smc->clcsock->sk->sk_sndbuf, SMC_BUF_MIN_SIZE); smc->sk.sk_rcvbuf = max(smc->clcsock->sk->sk_rcvbuf, SMC_BUF_MIN_SIZE); 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 = smc_pnet_init(); if (rc) return rc; rc = smc_llc_init(); if (rc) { pr_err("%s: smc_llc_init fails with %d\n", __func__, rc); goto out_pnet; } rc = smc_cdc_init(); if (rc) { pr_err("%s: smc_cdc_init fails with %d\n", __func__, rc); goto out_pnet; } rc = proto_register(&smc_proto, 1); if (rc) { pr_err("%s: proto_register(v4) fails with %d\n", __func__, rc); goto out_pnet; } rc = proto_register(&smc_proto6, 1); if (rc) { pr_err("%s: proto_register(v6) fails with %d\n", __func__, rc); goto out_proto; } rc = sock_register(&smc_sock_family_ops); if (rc) { pr_err("%s: sock_register fails with %d\n", __func__, rc); goto out_proto6; } INIT_HLIST_HEAD(&smc_v4_hashinfo.ht); INIT_HLIST_HEAD(&smc_v6_hashinfo.ht); rc = smc_ib_register_client(); if (rc) { pr_err("%s: ib_register fails with %d\n", __func__, rc); goto out_sock; } static_branch_enable(&tcp_have_smc); return 0; out_sock: sock_unregister(PF_SMC); out_proto6: proto_unregister(&smc_proto6); out_proto: proto_unregister(&smc_proto); out_pnet: smc_pnet_exit(); return rc; } static void __exit smc_exit(void) { struct smc_link_group *lgr, *lg; LIST_HEAD(lgr_freeing_list); spin_lock_bh(&smc_lgr_list.lock); if (!list_empty(&smc_lgr_list.list)) list_splice_init(&smc_lgr_list.list, &lgr_freeing_list); spin_unlock_bh(&smc_lgr_list.lock); list_for_each_entry_safe(lgr, lg, &lgr_freeing_list, list) { list_del_init(&lgr->list); cancel_delayed_work_sync(&lgr->free_work); smc_lgr_free(lgr); /* free link group */ } static_branch_disable(&tcp_have_smc); smc_ib_unregister_client(); sock_unregister(PF_SMC); proto_unregister(&smc_proto6); proto_unregister(&smc_proto); smc_pnet_exit(); } 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);