From 9bf9abead28abaf11d0776b6e0c5d34b6525e846 Mon Sep 17 00:00:00 2001 From: Ursula Braun Date: Mon, 9 Jan 2017 16:55:21 +0100 Subject: smc: link layer control (LLC) send and receive LLC messages CONFIRM_LINK (via IB message send and CQE) Signed-off-by: Ursula Braun Signed-off-by: David S. Miller --- net/smc/Makefile | 2 +- net/smc/af_smc.c | 94 ++++++++++++++++++++++++++++++- net/smc/smc_clc.h | 2 + net/smc/smc_core.c | 8 +++ net/smc/smc_core.h | 6 ++ net/smc/smc_llc.c | 158 +++++++++++++++++++++++++++++++++++++++++++++++++++++ net/smc/smc_llc.h | 63 +++++++++++++++++++++ 7 files changed, 330 insertions(+), 3 deletions(-) create mode 100644 net/smc/smc_llc.c create mode 100644 net/smc/smc_llc.h (limited to 'net/smc') diff --git a/net/smc/Makefile b/net/smc/Makefile index b19120ed7102..73320bf452b0 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_core.o smc_wr.o +smc-y := af_smc.o smc_pnet.o smc_ib.o smc_clc.o smc_core.o smc_wr.o smc_llc.o diff --git a/net/smc/af_smc.c b/net/smc/af_smc.c index 1026fad35998..1ae986d2762d 100644 --- a/net/smc/af_smc.c +++ b/net/smc/af_smc.c @@ -31,6 +31,7 @@ #include "smc.h" #include "smc_clc.h" +#include "smc_llc.h" #include "smc_core.h" #include "smc_ib.h" #include "smc_pnet.h" @@ -245,6 +246,41 @@ out: return rc; } +static int smc_clnt_conf_first_link(struct smc_sock *smc, union ib_gid *gid) +{ + 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; + } + + rc = smc_ib_modify_qp_rts(link); + if (rc) + return SMC_CLC_DECL_INTERR; + + smc_wr_remember_qp_attr(link); + /* send CONFIRM LINK response over RoCE fabric */ + rc = smc_llc_send_confirm_link(link, + link->smcibdev->mac[link->ibport - 1], + gid, SMC_LLC_RESP); + if (rc < 0) + return SMC_CLC_DECL_TCL; + + return rc; +} + static void smc_conn_save_peer_info(struct smc_sock *smc, struct smc_clc_msg_accept_confirm *clc) { @@ -358,7 +394,17 @@ static int smc_connect_rdma(struct smc_sock *smc) if (rc) goto out_err_unlock; - /* tbd in follow-on patch: llc_confirm */ + if (local_contact == SMC_FIRST_CONTACT) { + /* QP confirmation over RoCE fabric */ + reason_code = smc_clnt_conf_first_link( + smc, &smcibdev->gid[ibport - 1]); + 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); out_connected: @@ -543,6 +589,36 @@ static void smc_close_non_accepted(struct sock *sk) sock_put(sk); } +static int smc_serv_conf_first_link(struct smc_sock *smc) +{ + struct smc_link_group *lgr = smc->conn.lgr; + struct smc_link *link; + int rest; + int rc; + + link = &lgr->lnk[SMC_SINGLE_LINK]; + /* 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; +} + /* setup for RDMA connection of server */ static void smc_listen_work(struct work_struct *work) { @@ -655,13 +731,21 @@ static void smc_listen_work(struct work_struct *work) goto decline_rdma; } - /* tbd in follow-on patch: modify_qp, llc_confirm */ if (local_contact == SMC_FIRST_CONTACT) { rc = smc_ib_ready_link(link); if (rc) { reason_code = SMC_CLC_DECL_INTERR; goto decline_rdma; } + /* 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 */ + rc = reason_code; + goto out_err; + } + if (reason_code > 0) + goto decline_rdma; } out_connected: @@ -1111,6 +1195,12 @@ static int __init smc_init(void) 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 = proto_register(&smc_proto, 1); if (rc) { pr_err("%s: proto_register fails with %d\n", __func__, rc); diff --git a/net/smc/smc_clc.h b/net/smc/smc_clc.h index 5924d998b5ca..13db8ce177c9 100644 --- a/net/smc/smc_clc.h +++ b/net/smc/smc_clc.h @@ -33,6 +33,8 @@ static const char SMC_EYECATCHER[4] = {'\xe2', '\xd4', '\xc3', '\xd9'}; #define SMC_CLC_DECL_SYNCERR 0x04000000 /* synchronization error */ #define SMC_CLC_DECL_REPLY 0x06000000 /* reply to a received decline */ #define SMC_CLC_DECL_INTERR 0x99990000 /* internal error */ +#define SMC_CLC_DECL_TCL 0x02040000 /* timeout w4 QP confirm */ +#define SMC_CLC_DECL_SEND 0x07000000 /* sending problem */ struct smc_clc_msg_hdr { /* header1 of clc messages */ u8 eyecatcher[4]; /* eye catcher */ diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index 0e9adbd9cd68..906d88c266c0 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -21,9 +21,13 @@ #include "smc_core.h" #include "smc_ib.h" #include "smc_wr.h" +#include "smc_llc.h" +#define SMC_LGR_NUM_INCR 256 #define SMC_LGR_FREE_DELAY (600 * HZ) +static u32 smc_lgr_num; /* unique link group number */ + /* Register connection's alert token in our lookup structure. * To use rbtrees we have to implement our own insert core. * Requires @conns_lock @@ -152,6 +156,8 @@ static int smc_lgr_create(struct smc_sock *smc, __be32 peer_in_addr, INIT_LIST_HEAD(&lgr->sndbufs[i]); INIT_LIST_HEAD(&lgr->rmbs[i]); } + smc_lgr_num += SMC_LGR_NUM_INCR; + memcpy(&lgr->id, (u8 *)&smc_lgr_num, SMC_LGR_ID_SIZE); INIT_DELAYED_WORK(&lgr->free_work, smc_lgr_free_work); lgr->conns_all = RB_ROOT; @@ -177,6 +183,8 @@ static int smc_lgr_create(struct smc_sock *smc, __be32 peer_in_addr, rc = smc_wr_create_link(lnk); if (rc) goto destroy_qp; + init_completion(&lnk->llc_confirm); + init_completion(&lnk->llc_confirm_resp); smc->conn.lgr = lgr; rwlock_init(&lgr->conns_lock); diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h index f5ea52086d6d..27eb38056a27 100644 --- a/net/smc/smc_core.h +++ b/net/smc/smc_core.h @@ -73,6 +73,9 @@ struct smc_link { 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*/ + u8 link_id; /* unique # within link group */ + struct completion llc_confirm; /* wait for rx of conf link */ + struct completion llc_confirm_resp; /* wait 4 rx of cnf lnk rsp */ }; /* For now we just allow one parallel link per link group. The SMC protocol @@ -102,6 +105,8 @@ struct smc_rtoken { /* address/key of remote RMB */ u32 rkey; }; +#define SMC_LGR_ID_SIZE 4 + struct smc_link_group { struct list_head list; enum smc_lgr_role role; /* client or server */ @@ -125,6 +130,7 @@ struct smc_link_group { SMC_RMBS_PER_LGR_MAX)]; /* used rtoken elements */ + u8 id[SMC_LGR_ID_SIZE]; /* unique lgr id */ struct delayed_work free_work; /* delayed freeing of an lgr */ bool sync_err; /* lgr no longer fits to peer */ }; diff --git a/net/smc/smc_llc.c b/net/smc/smc_llc.c new file mode 100644 index 000000000000..c2f9165d13ef --- /dev/null +++ b/net/smc/smc_llc.c @@ -0,0 +1,158 @@ +/* + * Shared Memory Communications over RDMA (SMC-R) and RoCE + * + * Link Layer Control (LLC) + * + * For now, we only support the necessary "confirm link" functionality + * which happens for the first RoCE link after successful CLC handshake. + * + * Copyright IBM Corp. 2016 + * + * Author(s): Klaus Wacker + * Ursula Braun + */ + +#include +#include + +#include "smc.h" +#include "smc_core.h" +#include "smc_clc.h" +#include "smc_llc.h" + +/********************************** send *************************************/ + +struct smc_llc_tx_pend { +}; + +/* handler for send/transmission completion of an LLC msg */ +static void smc_llc_tx_handler(struct smc_wr_tx_pend_priv *pend, + struct smc_link *link, + enum ib_wc_status wc_status) +{ + /* future work: handle wc_status error for recovery and failover */ +} + +/** + * smc_llc_add_pending_send() - add LLC control message to pending WQE transmits + * @link: Pointer to SMC link used for sending LLC control message. + * @wr_buf: Out variable returning pointer to work request payload buffer. + * @pend: Out variable returning pointer to private pending WR tracking. + * It's the context the transmit complete handler will get. + * + * Reserves and pre-fills an entry for a pending work request send/tx. + * Used by mid-level smc_llc_send_msg() to prepare for later actual send/tx. + * Can sleep due to smc_get_ctrl_buf (if not in softirq context). + * + * Return: 0 on success, otherwise an error value. + */ +static int smc_llc_add_pending_send(struct smc_link *link, + struct smc_wr_buf **wr_buf, + struct smc_wr_tx_pend_priv **pend) +{ + int rc; + + rc = smc_wr_tx_get_free_slot(link, smc_llc_tx_handler, wr_buf, pend); + if (rc < 0) + return rc; + BUILD_BUG_ON_MSG( + sizeof(union smc_llc_msg) > SMC_WR_BUF_SIZE, + "must increase SMC_WR_BUF_SIZE to at least sizeof(struct smc_llc_msg)"); + BUILD_BUG_ON_MSG( + sizeof(union smc_llc_msg) != SMC_WR_TX_SIZE, + "must adapt SMC_WR_TX_SIZE to sizeof(struct smc_llc_msg); if not all smc_wr upper layer protocols use the same message size any more, must start to set link->wr_tx_sges[i].length on each individual smc_wr_tx_send()"); + BUILD_BUG_ON_MSG( + sizeof(struct smc_llc_tx_pend) > SMC_WR_TX_PEND_PRIV_SIZE, + "must increase SMC_WR_TX_PEND_PRIV_SIZE to at least sizeof(struct smc_llc_tx_pend)"); + return 0; +} + +/* high-level API to send LLC confirm link */ +int smc_llc_send_confirm_link(struct smc_link *link, u8 mac[], + union ib_gid *gid, + enum smc_llc_reqresp reqresp) +{ + struct smc_link_group *lgr = container_of(link, struct smc_link_group, + lnk[SMC_SINGLE_LINK]); + struct smc_llc_msg_confirm_link *confllc; + struct smc_wr_tx_pend_priv *pend; + struct smc_wr_buf *wr_buf; + int rc; + + rc = smc_llc_add_pending_send(link, &wr_buf, &pend); + if (rc) + return rc; + confllc = (struct smc_llc_msg_confirm_link *)wr_buf; + memset(confllc, 0, sizeof(*confllc)); + confllc->hd.common.type = SMC_LLC_CONFIRM_LINK; + confllc->hd.length = sizeof(struct smc_llc_msg_confirm_link); + if (reqresp == SMC_LLC_RESP) + confllc->hd.flags |= SMC_LLC_FLAG_RESP; + memcpy(confllc->sender_mac, mac, ETH_ALEN); + memcpy(confllc->sender_gid, gid, SMC_GID_SIZE); + hton24(confllc->sender_qp_num, link->roce_qp->qp_num); + /* confllc->link_num = SMC_SINGLE_LINK; already done by memset above */ + memcpy(confllc->link_uid, lgr->id, SMC_LGR_ID_SIZE); + confllc->max_links = SMC_LINKS_PER_LGR_MAX; + /* send llc message */ + rc = smc_wr_tx_send(link, pend); + return rc; +} + +/********************************* receive ***********************************/ + +static void smc_llc_rx_confirm_link(struct smc_link *link, + struct smc_llc_msg_confirm_link *llc) +{ + struct smc_link_group *lgr; + + lgr = container_of(link, struct smc_link_group, lnk[SMC_SINGLE_LINK]); + if (llc->hd.flags & SMC_LLC_FLAG_RESP) { + if (lgr->role == SMC_SERV) + complete(&link->llc_confirm_resp); + } else { + if (lgr->role == SMC_CLNT) { + link->link_id = llc->link_num; + complete(&link->llc_confirm); + } + } +} + +static void smc_llc_rx_handler(struct ib_wc *wc, void *buf) +{ + struct smc_link *link = (struct smc_link *)wc->qp->qp_context; + union smc_llc_msg *llc = buf; + + if (wc->byte_len < sizeof(*llc)) + return; /* short message */ + if (llc->raw.hdr.length != sizeof(*llc)) + return; /* invalid message */ + if (llc->raw.hdr.common.type == SMC_LLC_CONFIRM_LINK) + smc_llc_rx_confirm_link(link, &llc->confirm_link); +} + +/***************************** init, exit, misc ******************************/ + +static struct smc_wr_rx_handler smc_llc_rx_handlers[] = { + { + .handler = smc_llc_rx_handler, + .type = SMC_LLC_CONFIRM_LINK + }, + { + .handler = NULL, + } +}; + +int __init smc_llc_init(void) +{ + struct smc_wr_rx_handler *handler; + int rc = 0; + + for (handler = smc_llc_rx_handlers; handler->handler; handler++) { + INIT_HLIST_NODE(&handler->list); + rc = smc_wr_rx_register_handler(handler); + if (rc) + break; + } + return rc; +} diff --git a/net/smc/smc_llc.h b/net/smc/smc_llc.h new file mode 100644 index 000000000000..b472f853953a --- /dev/null +++ b/net/smc/smc_llc.h @@ -0,0 +1,63 @@ +/* + * Shared Memory Communications over RDMA (SMC-R) and RoCE + * + * Definitions for LLC (link layer control) message handling + * + * Copyright IBM Corp. 2016 + * + * Author(s): Klaus Wacker + * Ursula Braun + */ + +#ifndef SMC_LLC_H +#define SMC_LLC_H + +#include "smc_wr.h" + +#define SMC_LLC_FLAG_RESP 0x80 + +#define SMC_LLC_WAIT_FIRST_TIME (5 * HZ) + +enum smc_llc_reqresp { + SMC_LLC_REQ, + SMC_LLC_RESP +}; + +enum smc_llc_msg_type { + SMC_LLC_CONFIRM_LINK = 0x01, +}; + +#define SMC_LLC_DATA_LEN 40 + +struct smc_llc_hdr { + struct smc_wr_rx_hdr common; + u8 length; /* 44 */ + u8 reserved; + u8 flags; +}; + +struct smc_llc_msg_confirm_link { /* type 0x01 */ + struct smc_llc_hdr hd; + u8 sender_mac[ETH_ALEN]; + u8 sender_gid[SMC_GID_SIZE]; + u8 sender_qp_num[3]; + u8 link_num; + u8 link_uid[SMC_LGR_ID_SIZE]; + u8 max_links; + u8 reserved[9]; +}; + +union smc_llc_msg { + struct smc_llc_msg_confirm_link confirm_link; + struct { + struct smc_llc_hdr hdr; + u8 data[SMC_LLC_DATA_LEN]; + } raw; +}; + +/* transmit */ +int smc_llc_send_confirm_link(struct smc_link *lnk, u8 mac[], union ib_gid *gid, + enum smc_llc_reqresp reqresp); +int smc_llc_init(void) __init; + +#endif /* SMC_LLC_H */ -- cgit