* create smc_connection for SMC-sockets * determine suitable link group for a connection * create a new link group if necessary Signed-off-by: Ursula Braun <ubraun@xxxxxxxxxxxxxxxxxx> --- net/smc/Makefile | 2 +- net/smc/af_smc.c | 102 ++++++++++++++-- net/smc/smc.h | 36 ++++++ net/smc/smc_clc.c | 38 +++++- net/smc/smc_clc.h | 2 +- net/smc/smc_core.c | 336 +++++++++++++++++++++++++++++++++++++++++++++++++++++ net/smc/smc_core.h | 106 +++++++++++++++++ 7 files changed, 605 insertions(+), 17 deletions(-) create mode 100644 net/smc/smc_core.c create mode 100644 net/smc/smc_core.h diff --git a/net/smc/Makefile b/net/smc/Makefile index c0ad588..cb8bcd9 100644 --- a/net/smc/Makefile +++ b/net/smc/Makefile @@ -1,2 +1,2 @@ obj-$(CONFIG_SMC) += smc.o -smc-y := af_smc.o smc_pnet.o smc_ib.o smc_clc.o +smc-y := af_smc.o smc_pnet.o smc_ib.o smc_clc.o smc_core.o diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 05c705a..5fda37d 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -31,9 +31,19 @@ #include "smc.h" #include "smc_clc.h" +#include "smc_core.h" #include "smc_ib.h" #include "smc_pnet.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) @@ -235,11 +245,31 @@ int smc_netinfo_by_tcpsk(struct socket *clcsock, return rc; } +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; +} + +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 sockaddr_in *inaddr = (struct sockaddr_in *)smc->addr; 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; @@ -278,26 +308,43 @@ static int smc_connect_rdma(struct smc_sock *smc) if (reason_code > 0) goto decline_rdma; - /* tbd in follow-on patch: more steps to setup RDMA communcication, - * create connection, link group, link - */ + srv_first_contact = aclc.hdr.flag; + mutex_lock(&smc_create_lgr_pending); + local_contact = smc_conn_create(smc, inaddr->sin_addr.s_addr, 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 */ + goto decline_rdma_unlock; + } + link = &smc->conn.lgr->lnk[SMC_SINGLE_LINK]; + smc_conn_save_peer_info(smc, &aclc); + if (local_contact == SMC_FIRST_CONTACT) + smc_link_save_peer_info(link, &aclc); /* tbd in follow-on patch: more steps to setup RDMA communcication, * create rmbs, map rmbs, rtoken_handling, modify_qp */ rc = smc_clc_send_confirm(smc); if (rc) - goto out_err; + goto out_err_unlock; /* tbd in follow-on patch: llc_confirm */ + mutex_unlock(&smc_create_lgr_pending); out_connected: smc_copy_sock_settings_to_clc(smc); smc->sk.sk_state = SMC_ACTIVE; - return rc; + return rc ? rc : local_contact; +decline_rdma_unlock: + mutex_unlock(&smc_create_lgr_pending); + smc_conn_free(&smc->conn); decline_rdma: /* RDMA setup failed, switch back to TCP */ smc->use_fallback = true; @@ -308,6 +355,9 @@ static int smc_connect_rdma(struct smc_sock *smc) } goto out_connected; +out_err_unlock: + mutex_unlock(&smc_create_lgr_pending); + smc_conn_free(&smc->conn); out_err: return rc; } @@ -476,10 +526,12 @@ static void smc_listen_work(struct work_struct *work) 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; struct sockaddr_in peeraddr; + struct smc_link *link; int reason_code = 0; int rc = 0, len; __be32 subnet; @@ -527,15 +579,30 @@ static void smc_listen_work(struct work_struct *work) /* get address of the peer connected to the internal TCP socket */ kernel_getpeername(newclcsock, (struct sockaddr *)&peeraddr, &len); - /* tbd in follow-on patch: more steps to setup RDMA communcication, - * create connection, link_group, link - */ + /* allocate connection / link group */ + mutex_lock(&smc_create_lgr_pending); + local_contact = smc_conn_create(new_smc, peeraddr.sin_addr.s_addr, + smcibdev, ibport, &pclc.lcl, 0); + if (local_contact == SMC_REUSE_CONTACT) + /* lock no longer needed, free it due to following + * smc_clc_wait_msg() call + */ + mutex_unlock(&smc_create_lgr_pending); + 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 */ + goto decline_rdma; + } + link = &new_smc->conn.lgr->lnk[SMC_SINGLE_LINK]; /* tbd in follow-on patch: more steps to setup RDMA communcication, * create rmbs, map rmbs */ - rc = smc_clc_send_accept(new_smc); + rc = smc_clc_send_accept(new_smc, local_contact); if (rc) goto out_err; @@ -546,6 +613,9 @@ static void smc_listen_work(struct work_struct *work) goto out_err; if (reason_code > 0) goto decline_rdma; + smc_conn_save_peer_info(new_smc, &cclc); + if (local_contact == SMC_FIRST_CONTACT) + smc_link_save_peer_info(link, &cclc); /* tbd in follow-on patch: more steps to setup RDMA communcication, * rtoken_handling, modify_qp @@ -555,6 +625,8 @@ static void smc_listen_work(struct work_struct *work) sk_refcnt_debug_inc(newsmcsk); newsmcsk->sk_state = SMC_ACTIVE; enqueue: + if (local_contact == SMC_FIRST_CONTACT) + mutex_unlock(&smc_create_lgr_pending); lock_sock(&lsmc->sk); if (lsmc->sk.sk_state == SMC_LISTEN) { smc_accept_enqueue(&lsmc->sk, newsmcsk); @@ -570,6 +642,7 @@ static void smc_listen_work(struct work_struct *work) 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)) { rc = smc_clc_send_decline(new_smc, reason_code, 0); @@ -1024,6 +1097,17 @@ static int __init smc_init(void) 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); + smc_lgr_free(lgr); /* free link group */ + } smc_ib_unregister_client(); sock_unregister(PF_SMC); proto_unregister(&smc_proto); diff --git a/net/smc/smc.h b/net/smc/smc.h index 5946aae..11265bd 100644 --- a/net/smc/smc.h +++ b/net/smc/smc.h @@ -14,6 +14,8 @@ #include <linux/types.h> #include <net/sock.h> +#include "smc_ib.h" + #define SMCPROTO_SMC 0 /* SMC protocol */ #define SMC_MAX_PORTS 2 /* Max # of ports */ @@ -25,9 +27,19 @@ enum smc_state { /* possible states of an SMC socket */ SMC_LISTEN = 10, }; +struct smc_link_group; + +struct smc_connection { + struct rb_node alert_node; + struct smc_link_group *lgr; /* link group of connection */ + u32 alert_token_local; /* unique conn. id */ + u8 peer_conn_idx; /* from tcp handshake */ +}; + struct smc_sock { /* smc sock container */ struct sock sk; struct socket *clcsock; /* internal tcp socket */ + struct smc_connection conn; /* smc connection */ struct sockaddr *addr; /* inet connect address */ struct smc_sock *listen_smc; /* listen parent */ struct work_struct tcp_listen_work;/* handle tcp socket accepts */ @@ -46,6 +58,24 @@ static inline struct smc_sock *smc_sk(const struct sock *sk) extern u8 local_systemid[SMC_SYSTEMID_LEN]; /* unique system identifier */ +/* convert an u32 value into network byte order, store it into a 3 byte field */ +static inline void hton24(u8 *net, u32 host) +{ + __be32 t; + + t = cpu_to_be32(host); + memcpy(net, ((u8 *)&t) + 1, 3); +} + +/* convert a received 3 byte field into host byte order*/ +static inline u32 ntoh24(u8 *net) +{ + __be32 t = 0; + + memcpy(((u8 *)&t) + 1, net, 3); + return be32_to_cpu(t); +} + #ifdef CONFIG_XFRM static inline bool using_ipsec(struct smc_sock *smc) { @@ -59,7 +89,13 @@ static inline bool using_ipsec(struct smc_sock *smc) } #endif +struct smc_clc_msg_local; + int smc_netinfo_by_tcpsk(struct socket *clcsock, __be32 *subnet, u8 *prefix_len); +void smc_conn_free(struct smc_connection *conn); +int smc_conn_create(struct smc_sock *smc, __be32 peer_in_addr, + struct smc_ib_device *smcibdev, u8 ibport, + struct smc_clc_msg_local *lcl, int srv_first_contact); #endif /* __SMC_H */ diff --git a/net/smc/smc_clc.c b/net/smc/smc_clc.c index b613b86..f8e47c0 100644 --- a/net/smc/smc_clc.c +++ b/net/smc/smc_clc.c @@ -14,6 +14,7 @@ #include <net/tcp.h> #include "smc.h" +#include "smc_core.h" #include "smc_clc.h" #include "smc_ib.h" @@ -89,8 +90,13 @@ int smc_clc_wait_msg(struct smc_sock *smc, void *buf, int buflen, reason_code = -EPROTO; goto out; } - if (clcm->type == SMC_CLC_DECLINE) + if (clcm->type == SMC_CLC_DECLINE) { reason_code = SMC_CLC_DECL_REPLY; + if (ntohl(((struct smc_clc_msg_decline *)buf)->peer_diagnosis) + == SMC_CLC_DECL_SYNCERR) + smc->conn.lgr->sync_err = true; + } + out: return reason_code; } @@ -175,12 +181,15 @@ int smc_clc_send_proposal(struct smc_sock *smc, /* send CLC CONFIRM message across internal TCP socket */ int smc_clc_send_confirm(struct smc_sock *smc) { + struct smc_connection *conn = &smc->conn; struct smc_clc_msg_accept_confirm cclc; + struct smc_link *link; int reason_code = 0; struct msghdr msg; struct kvec vec; int len; + link = &conn->lgr->lnk[SMC_SINGLE_LINK]; /* send SMC Confirm CLC msg */ memset(&cclc, 0, sizeof(cclc)); memcpy(cclc.hdr.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)); @@ -188,12 +197,18 @@ int smc_clc_send_confirm(struct smc_sock *smc) cclc.hdr.length = htons(sizeof(cclc)); cclc.hdr.version = SMC_CLC_V1; /* SMC version */ memcpy(cclc.lcl.id_for_peer, local_systemid, sizeof(local_systemid)); - - /* tbd in follow-on patch: fill in link-related values */ + memcpy(&cclc.lcl.gid, &link->smcibdev->gid[link->ibport - 1], + SMC_GID_SIZE); + memcpy(&cclc.lcl.mac, &link->smcibdev->mac[link->ibport - 1], + sizeof(link->smcibdev->mac)); /* tbd in follow-on patch: fill in rmb-related values */ + hton24(cclc.qpn, link->roce_qp->qp_num); cclc.conn_idx = 1; /* for now: 1 RMB = 1 RMBE */ + cclc.rmbe_alert_token = htonl(conn->alert_token_local); + cclc.qp_mtu = min(link->path_mtu, link->peer_mtu); + hton24(cclc.psn, link->psn_initial); memcpy(cclc.trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)); @@ -214,26 +229,37 @@ int smc_clc_send_confirm(struct smc_sock *smc) } /* send CLC ACCEPT message across internal TCP socket */ -int smc_clc_send_accept(struct smc_sock *new_smc) +int smc_clc_send_accept(struct smc_sock *new_smc, int srv_first_contact) { + struct smc_connection *conn = &new_smc->conn; struct smc_clc_msg_accept_confirm aclc; + struct smc_link *link; struct msghdr msg; struct kvec vec; int rc = 0; int len; + link = &conn->lgr->lnk[SMC_SINGLE_LINK]; memset(&aclc, 0, sizeof(aclc)); memcpy(aclc.hdr.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)); aclc.hdr.type = SMC_CLC_ACCEPT; aclc.hdr.length = htons(sizeof(aclc)); aclc.hdr.version = SMC_CLC_V1; /* SMC version */ + if (srv_first_contact) + aclc.hdr.flag = 1; memcpy(aclc.lcl.id_for_peer, local_systemid, sizeof(local_systemid)); - - /* tbd in follow-on patch: fill in link-related values */ + memcpy(&aclc.lcl.gid, &link->smcibdev->gid[link->ibport - 1], + SMC_GID_SIZE); + memcpy(&aclc.lcl.mac, link->smcibdev->mac[link->ibport - 1], + sizeof(link->smcibdev->mac[link->ibport - 1])); /* tbd in follow-on patch: fill in rmb-related values */ + hton24(aclc.qpn, link->roce_qp->qp_num); aclc.conn_idx = 1; /* as long as 1 RMB = 1 RMBE */ + aclc.rmbe_alert_token = htonl(conn->alert_token_local); + aclc.qp_mtu = link->path_mtu; + hton24(aclc.psn, link->psn_initial); memcpy(aclc.trl.eyecatcher, SMC_EYECATCHER, sizeof(SMC_EYECATCHER)); memset(&msg, 0, sizeof(msg)); diff --git a/net/smc/smc_clc.h b/net/smc/smc_clc.h index 60bfc8b..5924d99 100644 --- a/net/smc/smc_clc.h +++ b/net/smc/smc_clc.h @@ -109,6 +109,6 @@ int smc_clc_send_decline(struct smc_sock *smc, u32 peer_diag_info, int smc_clc_send_proposal(struct smc_sock *smc, struct smc_ib_device *smcibdev, u8 ibport); int smc_clc_send_confirm(struct smc_sock *smc); -int smc_clc_send_accept(struct smc_sock *smc); +int smc_clc_send_accept(struct smc_sock *smc, int srv_first_contact); #endif diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c new file mode 100644 index 0000000..b88a829 --- /dev/null +++ b/net/smc/smc_core.c @@ -0,0 +1,336 @@ +/* + * Shared Memory Communications over RDMA (SMC-R) and RoCE + * + * Basic Transport Functions exploiting Infiniband API + * + * Copyright IBM Corp. 2016 + * + * Author(s): Ursula Braun <ubraun@xxxxxxxxxxxxxxxxxx> + */ + +#include <linux/socket.h> +#include <linux/if_vlan.h> +#include <linux/random.h> +#include <linux/workqueue.h> +#include <net/tcp.h> +#include <net/sock.h> +#include <rdma/ib_verbs.h> + +#include "smc.h" +#include "smc_clc.h" +#include "smc_core.h" +#include "smc_ib.h" + +#define SMC_LGR_FREE_DELAY (600 * HZ) + +/* Register connection's alert token in our lookup structure. + * To use rbtrees we have to implement our own insert core. + * Requires @conns_lock + * @smc connection to register + * Returns 0 on success, != otherwise. + */ +static void smc_lgr_add_alert_token(struct smc_connection *conn) +{ + struct rb_node **link, *parent = NULL; + u32 token = conn->alert_token_local; + + link = &conn->lgr->conns_all.rb_node; + while (*link) { + struct smc_connection *cur = rb_entry(*link, + struct smc_connection, alert_node); + + parent = *link; + if (cur->alert_token_local > token) + link = &parent->rb_left; + else + link = &parent->rb_right; + } + /* Put the new node there */ + rb_link_node(&conn->alert_node, parent, link); + rb_insert_color(&conn->alert_node, &conn->lgr->conns_all); +} + +/* Register connection in link group by assigning an alert token + * registered in a search tree. + * Requires @conns_lock + * Note that '0' is a reserved value and not assigned. + */ +static void smc_lgr_register_conn(struct smc_connection *conn) +{ + struct smc_sock *smc = container_of(conn, struct smc_sock, conn); + static atomic_t nexttoken = ATOMIC_INIT(0); + + /* find a new alert_token_local value not yet used by some connection + * in this link group + */ + sock_hold(&smc->sk); /* sock_put in smc_lgr_unregister_conn() */ + while (!conn->alert_token_local) { + conn->alert_token_local = atomic_inc_return(&nexttoken); + if (smc_lgr_find_conn(conn->alert_token_local, conn->lgr)) + conn->alert_token_local = 0; + } + smc_lgr_add_alert_token(conn); + conn->lgr->conns_num++; +} + +/* Unregister connection and reset the alert token of the given connection< + */ +static void __smc_lgr_unregister_conn(struct smc_connection *conn) +{ + struct smc_sock *smc = container_of(conn, struct smc_sock, conn); + struct smc_link_group *lgr = conn->lgr; + + rb_erase(&conn->alert_node, &lgr->conns_all); + lgr->conns_num--; + conn->alert_token_local = 0; + conn->lgr = NULL; + sock_put(&smc->sk); /* sock_hold in smc_lgr_register_conn() */ +} + +/* Unregister connection and trigger lgr freeing if applicable + */ +static void smc_lgr_unregister_conn(struct smc_connection *conn) +{ + struct smc_link_group *lgr = conn->lgr; + int reduced = 0; + + write_lock_bh(&lgr->conns_lock); + if (conn->alert_token_local) { + reduced = 1; + __smc_lgr_unregister_conn(conn); + } + write_unlock_bh(&lgr->conns_lock); + if (reduced && !lgr->conns_num) + schedule_delayed_work(&lgr->free_work, SMC_LGR_FREE_DELAY); +} + +static void smc_lgr_free_work(struct work_struct *work) +{ + struct smc_link_group *lgr = container_of(to_delayed_work(work), + struct smc_link_group, + free_work); + bool conns; + + spin_lock_bh(&smc_lgr_list.lock); + read_lock_bh(&lgr->conns_lock); + conns = RB_EMPTY_ROOT(&lgr->conns_all); + read_unlock_bh(&lgr->conns_lock); + if (!conns) { /* number of lgr connections is no longer zero */ + spin_unlock_bh(&smc_lgr_list.lock); + return; + } + list_del_init(&lgr->list); /* remove from smc_lgr_list */ + spin_unlock_bh(&smc_lgr_list.lock); + smc_lgr_free(lgr); +} + +/* create a new SMC link group */ +static int smc_lgr_create(struct smc_sock *smc, __be32 peer_in_addr, + struct smc_ib_device *smcibdev, u8 ibport, + char *peer_systemid, unsigned short vlan_id) +{ + struct smc_link_group *lgr; + struct smc_link *lnk; + u8 rndvec[3]; + int rc = 0; + + lgr = kzalloc(sizeof(*lgr), GFP_KERNEL); + if (!lgr) { + rc = -ENOMEM; + goto out; + } + lgr->role = smc->listen_smc ? SMC_SERV : SMC_CLNT; + lgr->sync_err = false; + lgr->daddr = peer_in_addr; + memcpy(lgr->peer_systemid, peer_systemid, SMC_SYSTEMID_LEN); + lgr->vlan_id = vlan_id; + INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work); + lgr->conns_all = RB_ROOT; + + lnk = &lgr->lnk[SMC_SINGLE_LINK]; + /* initialize link */ + lnk->smcibdev = smcibdev; + lnk->ibport = ibport; + lnk->path_mtu = smcibdev->pattr[ibport - 1].active_mtu; + get_random_bytes(rndvec, sizeof(rndvec)); + lnk->psn_initial = rndvec[0] + (rndvec[1] << 8) + (rndvec[2] << 16); + + smc->conn.lgr = lgr; + rwlock_init(&lgr->conns_lock); + spin_lock_bh(&smc_lgr_list.lock); + list_add(&lgr->list, &smc_lgr_list.list); + spin_unlock_bh(&smc_lgr_list.lock); +out: + return rc; +} + +/* remove a finished connection from its link group */ +void smc_conn_free(struct smc_connection *conn) +{ + struct smc_link_group *lgr = conn->lgr; + + if (!lgr) + return; + smc_lgr_unregister_conn(conn); +} + +static void smc_link_clear(struct smc_link *lnk) +{ + lnk->peer_qpn = 0; +} + +/* remove a link group */ +void smc_lgr_free(struct smc_link_group *lgr) +{ + smc_link_clear(&lgr->lnk[SMC_SINGLE_LINK]); + kfree(lgr); +} + +/* terminate linkgroup abnormally */ +void smc_lgr_terminate(struct smc_link_group *lgr) +{ + struct smc_connection *conn; + struct rb_node *node; + + spin_lock_bh(&smc_lgr_list.lock); + if (list_empty(&lgr->list)) { + /* termination already triggered */ + spin_unlock_bh(&smc_lgr_list.lock); + return; + } + /* do not use this link group for new connections */ + list_del_init(&lgr->list); + spin_unlock_bh(&smc_lgr_list.lock); + + write_lock_bh(&lgr->conns_lock); + node = rb_first(&lgr->conns_all); + while (node) { + conn = rb_entry(node, struct smc_connection, alert_node); + __smc_lgr_unregister_conn(conn); + node = rb_first(&lgr->conns_all); + } + write_unlock_bh(&lgr->conns_lock); + schedule_delayed_work(&lgr->free_work, SMC_LGR_FREE_DELAY); +} + +/* Determine vlan of internal TCP socket. + * @vlan_id: address to store the determined vlan id into + */ +static int smc_vlan_by_tcpsk(struct socket *clcsock, unsigned short *vlan_id) +{ + struct dst_entry *dst = sk_dst_get(clcsock->sk); + int rc = 0; + + *vlan_id = 0; + if (!dst) { + rc = -ENOTCONN; + goto out; + } + if (!dst->dev) { + rc = -ENODEV; + goto out_rel; + } + + if (is_vlan_dev(dst->dev)) + *vlan_id = vlan_dev_vlan_id(dst->dev); + +out_rel: + dst_release(dst); +out: + return rc; +} + +/* determine the link gid matching the vlan id of the link group */ +static int smc_link_determine_gid(struct smc_link_group *lgr) +{ + struct smc_link *lnk = &lgr->lnk[SMC_SINGLE_LINK]; + struct ib_gid_attr gattr; + union ib_gid gid; + int i; + + if (!lgr->vlan_id) { + lnk->gid = lnk->smcibdev->gid[lnk->ibport - 1]; + return 0; + } + + for (i = 0; i < lnk->smcibdev->pattr[lnk->ibport - 1].gid_tbl_len; + i++) { + if (ib_query_gid(lnk->smcibdev->ibdev, lnk->ibport, i, &gid, + &gattr)) + continue; + if (gattr.ndev && + (vlan_dev_vlan_id(gattr.ndev) == lgr->vlan_id)) { + lnk->gid = gid; + return 0; + } + } + return -ENODEV; +} + +/* create a new SMC connection (and a new link group if necessary) */ +int smc_conn_create(struct smc_sock *smc, __be32 peer_in_addr, + struct smc_ib_device *smcibdev, u8 ibport, + struct smc_clc_msg_local *lcl, int srv_first_contact) +{ + struct smc_connection *conn = &smc->conn; + struct smc_link_group *lgr; + unsigned short vlan_id; + enum smc_lgr_role role; + int local_contact = SMC_FIRST_CONTACT; + int rc = 0; + + role = smc->listen_smc ? SMC_SERV : SMC_CLNT; + rc = smc_vlan_by_tcpsk(smc->clcsock, &vlan_id); + if (rc) + return rc; + + if ((role == SMC_CLNT) && srv_first_contact) + /* create new link group as well */ + goto create; + + /* determine if an existing link group can be reused */ + spin_lock_bh(&smc_lgr_list.lock); + list_for_each_entry(lgr, &smc_lgr_list.list, list) { + write_lock_bh(&lgr->conns_lock); + if (!memcmp(lgr->peer_systemid, lcl->id_for_peer, + SMC_SYSTEMID_LEN) && + !memcmp(lgr->lnk[SMC_SINGLE_LINK].peer_gid, &lcl->gid, + SMC_GID_SIZE) && + !memcmp(lgr->lnk[SMC_SINGLE_LINK].peer_mac, lcl->mac, + sizeof(lcl->mac)) && + !lgr->sync_err && + (lgr->role == role) && + (lgr->vlan_id == vlan_id)) { + /* link group found */ + local_contact = SMC_REUSE_CONTACT; + conn->lgr = lgr; + smc_lgr_register_conn(conn); /* add smc conn to lgr */ + write_unlock_bh(&lgr->conns_lock); + break; + } + write_unlock_bh(&lgr->conns_lock); + } + spin_unlock_bh(&smc_lgr_list.lock); + + if (role == SMC_CLNT && !srv_first_contact && + (local_contact == SMC_FIRST_CONTACT)) { + /* Server reuses a link group, but Client wants to start + * a new one + * send out_of_sync decline, reason synchr. error + */ + return -ENOLINK; + } + +create: + if (local_contact == SMC_FIRST_CONTACT) { + rc = smc_lgr_create(smc, peer_in_addr, smcibdev, ibport, + lcl->id_for_peer, vlan_id); + if (rc) + goto out; + smc_lgr_register_conn(conn); /* add smc conn to lgr */ + rc = smc_link_determine_gid(conn->lgr); + } + +out: + return rc ? rc : local_contact; +} diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h new file mode 100644 index 0000000..14b787a --- /dev/null +++ b/net/smc/smc_core.h @@ -0,0 +1,106 @@ +/* + * Shared Memory Communications over RDMA (SMC-R) and RoCE + * + * Definitions for SMC Connections, Link Groups and Links + * + * Copyright IBM Corp. 2016 + * + * Author(s): Ursula Braun <ubraun@xxxxxxxxxxxxxxxxxx> + */ + +#ifndef _SMC_CORE_H +#define _SMC_CORE_H + +#include <rdma/ib_verbs.h> + +#include "smc.h" +#include "smc_ib.h" + +struct smc_lgr_list { /* list of link group definition */ + struct list_head list; + spinlock_t lock; /* protects list of link groups */ +}; + +extern struct smc_lgr_list smc_lgr_list; /* list of link groups */ + +enum smc_lgr_role { /* possible roles of a link group */ + SMC_CLNT, /* client */ + SMC_SERV /* server */ +}; + +struct smc_link { + struct smc_ib_device *smcibdev; /* ib-device */ + u8 ibport; /* port - values 1 | 2 */ + struct ib_qp *roce_qp; /* IB queue pair */ + struct ib_qp_attr qp_attr; /* IB queue pair attributes */ + union ib_gid gid; /* gid matching used vlan id */ + u32 peer_qpn; /* QP number of peer */ + enum ib_mtu path_mtu; /* used mtu */ + enum ib_mtu peer_mtu; /* mtu size of peer */ + u32 psn_initial; /* QP tx initial packet seqno */ + u32 peer_psn; /* QP rx initial packet seqno */ + u8 peer_mac[ETH_ALEN]; /* = gid[8:10||13:15] */ + u8 peer_gid[sizeof(union ib_gid)]; /* gid of peer*/ +}; + +/* For now we just allow one parallel link per link group. The SMC protocol + * allows more (up to 8). + */ +#define SMC_LINKS_PER_LGR_MAX 1 +#define SMC_SINGLE_LINK 0 + +#define SMC_FIRST_CONTACT 1 /* first contact to a peer */ +#define SMC_REUSE_CONTACT 0 /* follow-on contact to a peer*/ + +struct smc_link_group { + struct list_head list; + enum smc_lgr_role role; /* client or server */ + __be32 daddr; /* destination ip address */ + struct smc_link lnk[SMC_LINKS_PER_LGR_MAX]; /* smc link */ + char peer_systemid[SMC_SYSTEMID_LEN]; + /* unique system_id of peer */ + struct rb_root conns_all; /* connection tree */ + rwlock_t conns_lock; /* protects conns_all */ + unsigned int conns_num; /* current # of connections */ + unsigned short vlan_id; /* vlan id of link group */ + struct delayed_work free_work; /* delayed freeing of an lgr */ + bool sync_err; /* lgr no longer fits to peer */ +}; + +/* Find the connection associated with the given alert token in the link group. + * To use rbtrees we have to implement our own search core. + * Requires @conns_lock + * @token alert token to search for + * @lgr link group to search in + * Returns connection associated with token if found, NULL otherwise. + */ +static inline struct smc_connection *smc_lgr_find_conn( + u32 token, struct smc_link_group *lgr) +{ + struct smc_connection *res = NULL; + struct rb_node *node; + + node = lgr->conns_all.rb_node; + while (node) { + struct smc_connection *cur = rb_entry(node, + struct smc_connection, alert_node); + + if (cur->alert_token_local > token) { + node = node->rb_left; + } else { + if (cur->alert_token_local < token) { + node = node->rb_right; + } else { + res = cur; + break; + } + } + } + + return res; +} + +void smc_lgr_free(struct smc_link_group *lgr); +void smc_lgr_terminate(struct smc_link_group *lgr); + +#endif -- 2.8.4 -- To unsubscribe from this list: send the line "unsubscribe linux-s390" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html