From f38ba179c6ca94ebeb0ac6a0956c4ea533151ad8 Mon Sep 17 00:00:00 2001 From: Ursula Braun Date: Mon, 9 Jan 2017 16:55:19 +0100 Subject: smc: work request (WR) base for use by LLC and CDC The base containers for RDMA transport are work requests and completion queue entries processed through Infiniband verbs: * allocate and initialize these areas * map these areas to DMA * implement the basic communication consisting of work request posting and receival of completion queue events Signed-off-by: Ursula Braun Signed-off-by: David S. Miller --- net/smc/Makefile | 2 +- net/smc/smc.h | 5 + net/smc/smc_core.c | 11 ++ net/smc/smc_core.h | 30 +++ net/smc/smc_ib.c | 73 +++++++ net/smc/smc_ib.h | 11 ++ net/smc/smc_wr.c | 564 +++++++++++++++++++++++++++++++++++++++++++++++++++++ net/smc/smc_wr.h | 95 +++++++++ 8 files changed, 790 insertions(+), 1 deletion(-) create mode 100644 net/smc/smc_wr.c create mode 100644 net/smc/smc_wr.h (limited to 'net/smc') diff --git a/net/smc/Makefile b/net/smc/Makefile index cb8bcd9df53e..b19120ed7102 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-y := af_smc.o smc_pnet.o smc_ib.o smc_clc.o smc_core.o smc_wr.o diff --git a/net/smc/smc.h b/net/smc/smc.h index 2bf504492133..209a0b5f59cb 100644 --- a/net/smc/smc.h +++ b/net/smc/smc.h @@ -12,6 +12,7 @@ #include #include +#include /* __aligned */ #include #include "smc_ib.h" @@ -29,6 +30,10 @@ enum smc_state { /* possible states of an SMC socket */ struct smc_link_group; +struct smc_wr_rx_hdr { /* common prefix part of LLC and CDC to demultiplex */ + u8 type; +} __aligned(1); + struct smc_connection { struct rb_node alert_node; struct smc_link_group *lgr; /* link group of connection */ diff --git a/net/smc/smc_core.c b/net/smc/smc_core.c index e1b95728ca81..0eed4c154081 100644 --- a/net/smc/smc_core.c +++ b/net/smc/smc_core.c @@ -20,6 +20,7 @@ #include "smc_clc.h" #include "smc_core.h" #include "smc_ib.h" +#include "smc_wr.h" #define SMC_LGR_FREE_DELAY (600 * HZ) @@ -161,12 +162,20 @@ static int smc_lgr_create(struct smc_sock *smc, __be32 peer_in_addr, 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); + rc = smc_wr_alloc_link_mem(lnk); + if (rc) + goto free_lgr; + init_waitqueue_head(&lnk->wr_tx_wait); 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); + return 0; + +free_lgr: + kfree(lgr); out: return rc; } @@ -202,6 +211,8 @@ void smc_conn_free(struct smc_connection *conn) static void smc_link_clear(struct smc_link *lnk) { lnk->peer_qpn = 0; + smc_wr_free_link(lnk); + smc_wr_free_link_mem(lnk); } static void smc_lgr_free_sndbufs(struct smc_link_group *lgr) diff --git a/net/smc/smc_core.h b/net/smc/smc_core.h index bf0026db44e9..ca4587a95450 100644 --- a/net/smc/smc_core.h +++ b/net/smc/smc_core.h @@ -11,6 +11,7 @@ #ifndef _SMC_CORE_H #define _SMC_CORE_H +#include #include #include "smc.h" @@ -30,11 +31,40 @@ enum smc_lgr_role { /* possible roles of a link group */ SMC_SERV /* server */ }; +#define SMC_WR_BUF_SIZE 48 /* size of work request buffer */ + +struct smc_wr_buf { + u8 raw[SMC_WR_BUF_SIZE]; +}; + struct smc_link { struct smc_ib_device *smcibdev; /* ib-device */ u8 ibport; /* port - values 1 | 2 */ + struct ib_pd *roce_pd; /* IB protection domain, + * unique for every RoCE QP + */ struct ib_qp *roce_qp; /* IB queue pair */ struct ib_qp_attr qp_attr; /* IB queue pair attributes */ + + struct smc_wr_buf *wr_tx_bufs; /* WR send payload buffers */ + struct ib_send_wr *wr_tx_ibs; /* WR send meta data */ + struct ib_sge *wr_tx_sges; /* WR send gather meta data */ + struct smc_wr_tx_pend *wr_tx_pends; /* WR send waiting for CQE */ + /* above four vectors have wr_tx_cnt elements and use the same index */ + dma_addr_t wr_tx_dma_addr; /* DMA address of wr_tx_bufs */ + atomic_long_t wr_tx_id; /* seq # of last sent WR */ + unsigned long *wr_tx_mask; /* bit mask of used indexes */ + u32 wr_tx_cnt; /* number of WR send buffers */ + wait_queue_head_t wr_tx_wait; /* wait for free WR send buf */ + + struct smc_wr_buf *wr_rx_bufs; /* WR recv payload buffers */ + struct ib_recv_wr *wr_rx_ibs; /* WR recv meta data */ + struct ib_sge *wr_rx_sges; /* WR recv scatter meta data */ + /* above three vectors have wr_rx_cnt elements and use the same index */ + dma_addr_t wr_rx_dma_addr; /* DMA address of wr_rx_bufs */ + u64 wr_rx_id; /* seq # of last recv WR */ + u32 wr_rx_cnt; /* number of WR recv buffers */ + union ib_gid gid; /* gid matching used vlan id */ u32 peer_qpn; /* QP number of peer */ enum ib_mtu path_mtu; /* used mtu */ diff --git a/net/smc/smc_ib.c b/net/smc/smc_ib.c index 762b7e13c93d..9fb46a63a17e 100644 --- a/net/smc/smc_ib.c +++ b/net/smc/smc_ib.c @@ -17,6 +17,7 @@ #include "smc_pnet.h" #include "smc_ib.h" #include "smc_core.h" +#include "smc_wr.h" #include "smc.h" struct smc_ib_devices smc_ib_devices = { /* smc-registered ib devices */ @@ -30,6 +31,78 @@ u8 local_systemid[SMC_SYSTEMID_LEN] = SMC_LOCAL_SYSTEMID_RESET; /* unique system * identifier */ +void smc_ib_dealloc_protection_domain(struct smc_link *lnk) +{ + ib_dealloc_pd(lnk->roce_pd); + lnk->roce_pd = NULL; +} + +int smc_ib_create_protection_domain(struct smc_link *lnk) +{ + int rc; + + lnk->roce_pd = ib_alloc_pd(lnk->smcibdev->ibdev, 0); + rc = PTR_ERR_OR_ZERO(lnk->roce_pd); + if (IS_ERR(lnk->roce_pd)) + lnk->roce_pd = NULL; + return rc; +} + +static void smc_ib_qp_event_handler(struct ib_event *ibevent, void *priv) +{ + switch (ibevent->event) { + case IB_EVENT_DEVICE_FATAL: + case IB_EVENT_GID_CHANGE: + case IB_EVENT_PORT_ERR: + case IB_EVENT_QP_ACCESS_ERR: + /* tbd in follow-on patch: + * abnormal close of corresponding connections + */ + break; + default: + break; + } +} + +void smc_ib_destroy_queue_pair(struct smc_link *lnk) +{ + ib_destroy_qp(lnk->roce_qp); + lnk->roce_qp = NULL; +} + +/* create a queue pair within the protection domain for a link */ +int smc_ib_create_queue_pair(struct smc_link *lnk) +{ + struct ib_qp_init_attr qp_attr = { + .event_handler = smc_ib_qp_event_handler, + .qp_context = lnk, + .send_cq = lnk->smcibdev->roce_cq_send, + .recv_cq = lnk->smcibdev->roce_cq_recv, + .srq = NULL, + .cap = { + .max_send_wr = SMC_WR_BUF_CNT, + /* include unsolicited rdma_writes as well, + * there are max. 2 RDMA_WRITE per 1 WR_SEND + */ + .max_recv_wr = SMC_WR_BUF_CNT * 3, + .max_send_sge = SMC_IB_MAX_SEND_SGE, + .max_recv_sge = 1, + .max_inline_data = SMC_WR_TX_SIZE, + }, + .sq_sig_type = IB_SIGNAL_REQ_WR, + .qp_type = IB_QPT_RC, + }; + int rc; + + lnk->roce_qp = ib_create_qp(lnk->roce_pd, &qp_attr); + rc = PTR_ERR_OR_ZERO(lnk->roce_qp); + if (IS_ERR(lnk->roce_qp)) + lnk->roce_qp = NULL; + else + smc_wr_remember_qp_attr(lnk); + return rc; +} + /* map a new TX or RX buffer to DMA */ int smc_ib_buf_map(struct smc_ib_device *smcibdev, int buf_size, struct smc_buf_desc *buf_slot, diff --git a/net/smc/smc_ib.h b/net/smc/smc_ib.h index c3b61726861a..441fd168911d 100644 --- a/net/smc/smc_ib.h +++ b/net/smc/smc_ib.h @@ -16,6 +16,8 @@ #define SMC_MAX_PORTS 2 /* Max # of ports */ #define SMC_GID_SIZE sizeof(union ib_gid) +#define SMC_IB_MAX_SEND_SGE 2 + struct smc_ib_devices { /* list of smc ib devices definition */ struct list_head list; spinlock_t lock; /* protects list of smc ib devices */ @@ -27,12 +29,17 @@ struct smc_ib_device { /* ib-device infos for smc */ struct list_head list; struct ib_device *ibdev; struct ib_port_attr pattr[SMC_MAX_PORTS]; /* ib dev. port attrs */ + struct ib_cq *roce_cq_send; /* send completion queue */ + struct ib_cq *roce_cq_recv; /* recv completion queue */ + struct tasklet_struct send_tasklet; /* called by send cq handler */ + struct tasklet_struct recv_tasklet; /* called by recv cq handler */ char mac[SMC_MAX_PORTS][6]; /* mac address per port*/ union ib_gid gid[SMC_MAX_PORTS]; /* gid per port */ u8 initialized : 1; /* ib dev CQ, evthdl done */ }; struct smc_buf_desc; +struct smc_link; int smc_ib_register_client(void) __init; void smc_ib_unregister_client(void); @@ -41,5 +48,9 @@ int smc_ib_remember_port_attr(struct smc_ib_device *smcibdev, u8 ibport); int smc_ib_buf_map(struct smc_ib_device *smcibdev, int buf_size, struct smc_buf_desc *buf_slot, enum dma_data_direction data_direction); +void smc_ib_dealloc_protection_domain(struct smc_link *lnk); +int smc_ib_create_protection_domain(struct smc_link *lnk); +void smc_ib_destroy_queue_pair(struct smc_link *lnk); +int smc_ib_create_queue_pair(struct smc_link *lnk); #endif diff --git a/net/smc/smc_wr.c b/net/smc/smc_wr.c new file mode 100644 index 000000000000..a2bc6b612d03 --- /dev/null +++ b/net/smc/smc_wr.c @@ -0,0 +1,564 @@ +/* + * Shared Memory Communications over RDMA (SMC-R) and RoCE + * + * Work Requests exploiting Infiniband API + * + * Work requests (WR) of type ib_post_send or ib_post_recv respectively + * are submitted to either RC SQ or RC RQ respectively + * (reliably connected send/receive queue) + * and become work queue entries (WQEs). + * While an SQ WR/WQE is pending, we track it until transmission completion. + * Through a send or receive completion queue (CQ) respectively, + * we get completion queue entries (CQEs) [aka work completions (WCs)]. + * Since the CQ callback is called from IRQ context, we split work by using + * bottom halves implemented by tasklets. + * + * SMC uses this to exchange LLC (link layer control) + * and CDC (connection data control) messages. + * + * Copyright IBM Corp. 2016 + * + * Author(s): Steffen Maier + */ + +#include +#include +#include +#include +#include + +#include "smc.h" +#include "smc_wr.h" + +#define SMC_WR_MAX_POLL_CQE 10 /* max. # of compl. queue elements in 1 poll */ + +#define SMC_WR_RX_HASH_BITS 4 +static DEFINE_HASHTABLE(smc_wr_rx_hash, SMC_WR_RX_HASH_BITS); +static DEFINE_SPINLOCK(smc_wr_rx_hash_lock); + +struct smc_wr_tx_pend { /* control data for a pending send request */ + u64 wr_id; /* work request id sent */ + smc_wr_tx_handler handler; + enum ib_wc_status wc_status; /* CQE status */ + struct smc_link *link; + u32 idx; + struct smc_wr_tx_pend_priv priv; +}; + +/******************************** send queue *********************************/ + +/*------------------------------- completion --------------------------------*/ + +static inline int smc_wr_tx_find_pending_index(struct smc_link *link, u64 wr_id) +{ + u32 i; + + for (i = 0; i < link->wr_tx_cnt; i++) { + if (link->wr_tx_pends[i].wr_id == wr_id) + return i; + } + return link->wr_tx_cnt; +} + +static inline void smc_wr_tx_process_cqe(struct ib_wc *wc) +{ + struct smc_wr_tx_pend pnd_snd; + struct smc_link *link; + u32 pnd_snd_idx; + int i; + + link = wc->qp->qp_context; + pnd_snd_idx = smc_wr_tx_find_pending_index(link, wc->wr_id); + if (pnd_snd_idx == link->wr_tx_cnt) + return; + link->wr_tx_pends[pnd_snd_idx].wc_status = wc->status; + memcpy(&pnd_snd, &link->wr_tx_pends[pnd_snd_idx], sizeof(pnd_snd)); + /* clear the full struct smc_wr_tx_pend including .priv */ + memset(&link->wr_tx_pends[pnd_snd_idx], 0, + sizeof(link->wr_tx_pends[pnd_snd_idx])); + memset(&link->wr_tx_bufs[pnd_snd_idx], 0, + sizeof(link->wr_tx_bufs[pnd_snd_idx])); + if (!test_and_clear_bit(pnd_snd_idx, link->wr_tx_mask)) + return; + if (wc->status) { + for_each_set_bit(i, link->wr_tx_mask, link->wr_tx_cnt) { + /* clear full struct smc_wr_tx_pend including .priv */ + memset(&link->wr_tx_pends[i], 0, + sizeof(link->wr_tx_pends[i])); + memset(&link->wr_tx_bufs[i], 0, + sizeof(link->wr_tx_bufs[i])); + clear_bit(i, link->wr_tx_mask); + } + /* tbd in future patch: terminate connections of this link + * group abnormally + */ + } + if (pnd_snd.handler) + pnd_snd.handler(&pnd_snd.priv, link, wc->status); + wake_up(&link->wr_tx_wait); +} + +static void smc_wr_tx_tasklet_fn(unsigned long data) +{ + struct smc_ib_device *dev = (struct smc_ib_device *)data; + struct ib_wc wc[SMC_WR_MAX_POLL_CQE]; + int i = 0, rc; + int polled = 0; + +again: + polled++; + do { + rc = ib_poll_cq(dev->roce_cq_send, SMC_WR_MAX_POLL_CQE, wc); + if (polled == 1) { + ib_req_notify_cq(dev->roce_cq_send, + IB_CQ_NEXT_COMP | + IB_CQ_REPORT_MISSED_EVENTS); + } + if (!rc) + break; + for (i = 0; i < rc; i++) + smc_wr_tx_process_cqe(&wc[i]); + } while (rc > 0); + if (polled == 1) + goto again; +} + +void smc_wr_tx_cq_handler(struct ib_cq *ib_cq, void *cq_context) +{ + struct smc_ib_device *dev = (struct smc_ib_device *)cq_context; + + tasklet_schedule(&dev->send_tasklet); +} + +/*---------------------------- request submission ---------------------------*/ + +static inline int smc_wr_tx_get_free_slot_index(struct smc_link *link, u32 *idx) +{ + *idx = link->wr_tx_cnt; + for_each_clear_bit(*idx, link->wr_tx_mask, link->wr_tx_cnt) { + if (!test_and_set_bit(*idx, link->wr_tx_mask)) + return 0; + } + *idx = link->wr_tx_cnt; + return -EBUSY; +} + +/** + * smc_wr_tx_get_free_slot() - returns buffer for message assembly, + * and sets info for pending transmit tracking + * @link: Pointer to smc_link used to later send the message. + * @handler: Send completion handler function pointer. + * @wr_buf: Out value returns pointer to message buffer. + * @wr_pend_priv: Out value returns pointer serving as handler context. + * + * Return: 0 on success, or -errno on error. + */ +int smc_wr_tx_get_free_slot(struct smc_link *link, + smc_wr_tx_handler handler, + struct smc_wr_buf **wr_buf, + struct smc_wr_tx_pend_priv **wr_pend_priv) +{ + struct smc_wr_tx_pend *wr_pend; + struct ib_send_wr *wr_ib; + u64 wr_id; + u32 idx; + int rc; + + *wr_buf = NULL; + *wr_pend_priv = NULL; + if (in_softirq()) { + rc = smc_wr_tx_get_free_slot_index(link, &idx); + if (rc) + return rc; + } else { + rc = wait_event_interruptible_timeout( + link->wr_tx_wait, + (smc_wr_tx_get_free_slot_index(link, &idx) != -EBUSY), + SMC_WR_TX_WAIT_FREE_SLOT_TIME); + if (!rc) { + /* tbd in future patch: timeout - terminate connections + * of this link group abnormally + */ + return -EPIPE; + } + if (rc == -ERESTARTSYS) + return -EINTR; + if (idx == link->wr_tx_cnt) + return -EPIPE; + } + wr_id = smc_wr_tx_get_next_wr_id(link); + wr_pend = &link->wr_tx_pends[idx]; + wr_pend->wr_id = wr_id; + wr_pend->handler = handler; + wr_pend->link = link; + wr_pend->idx = idx; + wr_ib = &link->wr_tx_ibs[idx]; + wr_ib->wr_id = wr_id; + *wr_buf = &link->wr_tx_bufs[idx]; + *wr_pend_priv = &wr_pend->priv; + return 0; +} + +int smc_wr_tx_put_slot(struct smc_link *link, + struct smc_wr_tx_pend_priv *wr_pend_priv) +{ + struct smc_wr_tx_pend *pend; + + pend = container_of(wr_pend_priv, struct smc_wr_tx_pend, priv); + if (pend->idx < link->wr_tx_cnt) { + /* clear the full struct smc_wr_tx_pend including .priv */ + memset(&link->wr_tx_pends[pend->idx], 0, + sizeof(link->wr_tx_pends[pend->idx])); + memset(&link->wr_tx_bufs[pend->idx], 0, + sizeof(link->wr_tx_bufs[pend->idx])); + test_and_clear_bit(pend->idx, link->wr_tx_mask); + return 1; + } + + return 0; +} + +/* Send prepared WR slot via ib_post_send. + * @priv: pointer to smc_wr_tx_pend_priv identifying prepared message buffer + */ +int smc_wr_tx_send(struct smc_link *link, struct smc_wr_tx_pend_priv *priv) +{ + struct ib_send_wr *failed_wr = NULL; + struct smc_wr_tx_pend *pend; + int rc; + + ib_req_notify_cq(link->smcibdev->roce_cq_send, + IB_CQ_SOLICITED_MASK | IB_CQ_REPORT_MISSED_EVENTS); + pend = container_of(priv, struct smc_wr_tx_pend, priv); + rc = ib_post_send(link->roce_qp, &link->wr_tx_ibs[pend->idx], + &failed_wr); + if (rc) + smc_wr_tx_put_slot(link, priv); + return rc; +} + +/****************************** receive queue ********************************/ + +int smc_wr_rx_register_handler(struct smc_wr_rx_handler *handler) +{ + struct smc_wr_rx_handler *h_iter; + int rc = 0; + + spin_lock(&smc_wr_rx_hash_lock); + hash_for_each_possible(smc_wr_rx_hash, h_iter, list, handler->type) { + if (h_iter->type == handler->type) { + rc = -EEXIST; + goto out_unlock; + } + } + hash_add(smc_wr_rx_hash, &handler->list, handler->type); +out_unlock: + spin_unlock(&smc_wr_rx_hash_lock); + return rc; +} + +/* Demultiplex a received work request based on the message type to its handler. + * Relies on smc_wr_rx_hash having been completely filled before any IB WRs, + * and not being modified any more afterwards so we don't need to lock it. + */ +static inline void smc_wr_rx_demultiplex(struct ib_wc *wc) +{ + struct smc_link *link = (struct smc_link *)wc->qp->qp_context; + struct smc_wr_rx_handler *handler; + struct smc_wr_rx_hdr *wr_rx; + u64 temp_wr_id; + u32 index; + + if (wc->byte_len < sizeof(*wr_rx)) + return; /* short message */ + temp_wr_id = wc->wr_id; + index = do_div(temp_wr_id, link->wr_rx_cnt); + wr_rx = (struct smc_wr_rx_hdr *)&link->wr_rx_bufs[index]; + hash_for_each_possible(smc_wr_rx_hash, handler, list, wr_rx->type) { + if (handler->type == wr_rx->type) + handler->handler(wc, wr_rx); + } +} + +static inline void smc_wr_rx_process_cqes(struct ib_wc wc[], int num) +{ + struct smc_link *link; + int i; + + for (i = 0; i < num; i++) { + link = wc[i].qp->qp_context; + if (wc[i].status == IB_WC_SUCCESS) { + smc_wr_rx_demultiplex(&wc[i]); + smc_wr_rx_post(link); /* refill WR RX */ + } else { + /* handle status errors */ + switch (wc[i].status) { + case IB_WC_RETRY_EXC_ERR: + case IB_WC_RNR_RETRY_EXC_ERR: + case IB_WC_WR_FLUSH_ERR: + /* tbd in future patch: terminate connections of this + * link group abnormally + */ + break; + default: + smc_wr_rx_post(link); /* refill WR RX */ + break; + } + } + } +} + +static void smc_wr_rx_tasklet_fn(unsigned long data) +{ + struct smc_ib_device *dev = (struct smc_ib_device *)data; + struct ib_wc wc[SMC_WR_MAX_POLL_CQE]; + int polled = 0; + int rc; + +again: + polled++; + do { + memset(&wc, 0, sizeof(wc)); + rc = ib_poll_cq(dev->roce_cq_recv, SMC_WR_MAX_POLL_CQE, wc); + if (polled == 1) { + ib_req_notify_cq(dev->roce_cq_recv, + IB_CQ_SOLICITED_MASK + | IB_CQ_REPORT_MISSED_EVENTS); + } + if (!rc) + break; + smc_wr_rx_process_cqes(&wc[0], rc); + } while (rc > 0); + if (polled == 1) + goto again; +} + +void smc_wr_rx_cq_handler(struct ib_cq *ib_cq, void *cq_context) +{ + struct smc_ib_device *dev = (struct smc_ib_device *)cq_context; + + tasklet_schedule(&dev->recv_tasklet); +} + +int smc_wr_rx_post_init(struct smc_link *link) +{ + u32 i; + int rc = 0; + + for (i = 0; i < link->wr_rx_cnt; i++) + rc = smc_wr_rx_post(link); + return rc; +} + +/***************************** init, exit, misc ******************************/ + +void smc_wr_remember_qp_attr(struct smc_link *lnk) +{ + struct ib_qp_attr *attr = &lnk->qp_attr; + struct ib_qp_init_attr init_attr; + + memset(attr, 0, sizeof(*attr)); + memset(&init_attr, 0, sizeof(init_attr)); + ib_query_qp(lnk->roce_qp, attr, + IB_QP_STATE | + IB_QP_CUR_STATE | + IB_QP_PKEY_INDEX | + IB_QP_PORT | + IB_QP_QKEY | + IB_QP_AV | + IB_QP_PATH_MTU | + IB_QP_TIMEOUT | + IB_QP_RETRY_CNT | + IB_QP_RNR_RETRY | + IB_QP_RQ_PSN | + IB_QP_ALT_PATH | + IB_QP_MIN_RNR_TIMER | + IB_QP_SQ_PSN | + IB_QP_PATH_MIG_STATE | + IB_QP_CAP | + IB_QP_DEST_QPN, + &init_attr); + + lnk->wr_tx_cnt = min_t(size_t, SMC_WR_BUF_CNT, + lnk->qp_attr.cap.max_send_wr); + lnk->wr_rx_cnt = min_t(size_t, SMC_WR_BUF_CNT * 3, + lnk->qp_attr.cap.max_recv_wr); +} + +static void smc_wr_init_sge(struct smc_link *lnk) +{ + u32 i; + + for (i = 0; i < lnk->wr_tx_cnt; i++) { + lnk->wr_tx_sges[i].addr = + lnk->wr_tx_dma_addr + i * SMC_WR_BUF_SIZE; + lnk->wr_tx_sges[i].length = SMC_WR_TX_SIZE; + lnk->wr_tx_ibs[i].next = NULL; + lnk->wr_tx_ibs[i].sg_list = &lnk->wr_tx_sges[i]; + lnk->wr_tx_ibs[i].num_sge = 1; + lnk->wr_tx_ibs[i].opcode = IB_WR_SEND; + lnk->wr_tx_ibs[i].send_flags = + IB_SEND_SIGNALED | IB_SEND_SOLICITED | IB_SEND_INLINE; + } + for (i = 0; i < lnk->wr_rx_cnt; i++) { + lnk->wr_rx_sges[i].addr = + lnk->wr_rx_dma_addr + i * SMC_WR_BUF_SIZE; + lnk->wr_rx_sges[i].length = SMC_WR_BUF_SIZE; + lnk->wr_rx_ibs[i].next = NULL; + lnk->wr_rx_ibs[i].sg_list = &lnk->wr_rx_sges[i]; + lnk->wr_rx_ibs[i].num_sge = 1; + } +} + +void smc_wr_free_link(struct smc_link *lnk) +{ + struct ib_device *ibdev; + + memset(lnk->wr_tx_mask, 0, + BITS_TO_LONGS(SMC_WR_BUF_CNT) * sizeof(*lnk->wr_tx_mask)); + + if (!lnk->smcibdev) + return; + ibdev = lnk->smcibdev->ibdev; + + if (lnk->wr_rx_dma_addr) { + ib_dma_unmap_single(ibdev, lnk->wr_rx_dma_addr, + SMC_WR_BUF_SIZE * lnk->wr_rx_cnt, + DMA_FROM_DEVICE); + lnk->wr_rx_dma_addr = 0; + } + if (lnk->wr_tx_dma_addr) { + ib_dma_unmap_single(ibdev, lnk->wr_tx_dma_addr, + SMC_WR_BUF_SIZE * lnk->wr_tx_cnt, + DMA_TO_DEVICE); + lnk->wr_tx_dma_addr = 0; + } +} + +void smc_wr_free_link_mem(struct smc_link *lnk) +{ + kfree(lnk->wr_tx_pends); + lnk->wr_tx_pends = NULL; + kfree(lnk->wr_tx_mask); + lnk->wr_tx_mask = NULL; + kfree(lnk->wr_tx_sges); + lnk->wr_tx_sges = NULL; + kfree(lnk->wr_rx_sges); + lnk->wr_rx_sges = NULL; + kfree(lnk->wr_rx_ibs); + lnk->wr_rx_ibs = NULL; + kfree(lnk->wr_tx_ibs); + lnk->wr_tx_ibs = NULL; + kfree(lnk->wr_tx_bufs); + lnk->wr_tx_bufs = NULL; + kfree(lnk->wr_rx_bufs); + lnk->wr_rx_bufs = NULL; +} + +int smc_wr_alloc_link_mem(struct smc_link *link) +{ + /* allocate link related memory */ + link->wr_tx_bufs = kcalloc(SMC_WR_BUF_CNT, SMC_WR_BUF_SIZE, GFP_KERNEL); + if (!link->wr_tx_bufs) + goto no_mem; + link->wr_rx_bufs = kcalloc(SMC_WR_BUF_CNT * 3, SMC_WR_BUF_SIZE, + GFP_KERNEL); + if (!link->wr_rx_bufs) + goto no_mem_wr_tx_bufs; + link->wr_tx_ibs = kcalloc(SMC_WR_BUF_CNT, sizeof(link->wr_tx_ibs[0]), + GFP_KERNEL); + if (!link->wr_tx_ibs) + goto no_mem_wr_rx_bufs; + link->wr_rx_ibs = kcalloc(SMC_WR_BUF_CNT * 3, + sizeof(link->wr_rx_ibs[0]), + GFP_KERNEL); + if (!link->wr_rx_ibs) + goto no_mem_wr_tx_ibs; + link->wr_tx_sges = kcalloc(SMC_WR_BUF_CNT, sizeof(link->wr_tx_sges[0]), + GFP_KERNEL); + if (!link->wr_tx_sges) + goto no_mem_wr_rx_ibs; + link->wr_rx_sges = kcalloc(SMC_WR_BUF_CNT * 3, + sizeof(link->wr_rx_sges[0]), + GFP_KERNEL); + if (!link->wr_rx_sges) + goto no_mem_wr_tx_sges; + link->wr_tx_mask = kzalloc( + BITS_TO_LONGS(SMC_WR_BUF_CNT) * sizeof(*link->wr_tx_mask), + GFP_KERNEL); + if (!link->wr_tx_mask) + goto no_mem_wr_rx_sges; + link->wr_tx_pends = kcalloc(SMC_WR_BUF_CNT, + sizeof(link->wr_tx_pends[0]), + GFP_KERNEL); + if (!link->wr_tx_pends) + goto no_mem_wr_tx_mask; + return 0; + +no_mem_wr_tx_mask: + kfree(link->wr_tx_mask); +no_mem_wr_rx_sges: + kfree(link->wr_rx_sges); +no_mem_wr_tx_sges: + kfree(link->wr_tx_sges); +no_mem_wr_rx_ibs: + kfree(link->wr_rx_ibs); +no_mem_wr_tx_ibs: + kfree(link->wr_tx_ibs); +no_mem_wr_rx_bufs: + kfree(link->wr_rx_bufs); +no_mem_wr_tx_bufs: + kfree(link->wr_tx_bufs); +no_mem: + return -ENOMEM; +} + +void smc_wr_remove_dev(struct smc_ib_device *smcibdev) +{ + tasklet_kill(&smcibdev->recv_tasklet); + tasklet_kill(&smcibdev->send_tasklet); +} + +void smc_wr_add_dev(struct smc_ib_device *smcibdev) +{ + tasklet_init(&smcibdev->recv_tasklet, smc_wr_rx_tasklet_fn, + (unsigned long)smcibdev); + tasklet_init(&smcibdev->send_tasklet, smc_wr_tx_tasklet_fn, + (unsigned long)smcibdev); +} + +int smc_wr_create_link(struct smc_link *lnk) +{ + struct ib_device *ibdev = lnk->smcibdev->ibdev; + int rc = 0; + + smc_wr_tx_set_wr_id(&lnk->wr_tx_id, 0); + lnk->wr_rx_id = 0; + lnk->wr_rx_dma_addr = ib_dma_map_single( + ibdev, lnk->wr_rx_bufs, SMC_WR_BUF_SIZE * lnk->wr_rx_cnt, + DMA_FROM_DEVICE); + if (ib_dma_mapping_error(ibdev, lnk->wr_rx_dma_addr)) { + lnk->wr_rx_dma_addr = 0; + rc = -EIO; + goto out; + } + lnk->wr_tx_dma_addr = ib_dma_map_single( + ibdev, lnk->wr_tx_bufs, SMC_WR_BUF_SIZE * lnk->wr_tx_cnt, + DMA_TO_DEVICE); + if (ib_dma_mapping_error(ibdev, lnk->wr_tx_dma_addr)) { + rc = -EIO; + goto dma_unmap; + } + smc_wr_init_sge(lnk); + memset(lnk->wr_tx_mask, 0, + BITS_TO_LONGS(SMC_WR_BUF_CNT) * sizeof(*lnk->wr_tx_mask)); + return rc; + +dma_unmap: + ib_dma_unmap_single(ibdev, lnk->wr_rx_dma_addr, + SMC_WR_BUF_SIZE * lnk->wr_rx_cnt, + DMA_FROM_DEVICE); + lnk->wr_rx_dma_addr = 0; +out: + return rc; +} diff --git a/net/smc/smc_wr.h b/net/smc/smc_wr.h new file mode 100644 index 000000000000..0b626728ce44 --- /dev/null +++ b/net/smc/smc_wr.h @@ -0,0 +1,95 @@ +/* + * Shared Memory Communications over RDMA (SMC-R) and RoCE + * + * Work Requests exploiting Infiniband API + * + * Copyright IBM Corp. 2016 + * + * Author(s): Steffen Maier + */ + +#ifndef SMC_WR_H +#define SMC_WR_H + +#include +#include +#include + +#include "smc.h" +#include "smc_core.h" + +#define SMC_WR_MAX_CQE 32768 /* max. # of completion queue elements */ +#define SMC_WR_BUF_CNT 16 /* # of ctrl buffers per link */ + +#define SMC_WR_TX_WAIT_FREE_SLOT_TIME (10 * HZ) +#define SMC_WR_TX_WAIT_PENDING_TIME (5 * HZ) + +#define SMC_WR_TX_SIZE 44 /* actual size of wr_send data (<=SMC_WR_BUF_SIZE) */ + +#define SMC_WR_TX_PEND_PRIV_SIZE 32 + +struct smc_wr_tx_pend_priv { + u8 priv[SMC_WR_TX_PEND_PRIV_SIZE]; +}; + +typedef void (*smc_wr_tx_handler)(struct smc_wr_tx_pend_priv *, + struct smc_link *, + enum ib_wc_status); + +struct smc_wr_rx_handler { + struct hlist_node list; /* hash table collision resolution */ + void (*handler)(struct ib_wc *, void *); + u8 type; +}; + +/* Only used by RDMA write WRs. + * All other WRs (CDC/LLC) use smc_wr_tx_send handling WR_ID implicitly + */ +static inline long smc_wr_tx_get_next_wr_id(struct smc_link *link) +{ + return atomic_long_inc_return(&link->wr_tx_id); +} + +static inline void smc_wr_tx_set_wr_id(atomic_long_t *wr_tx_id, long val) +{ + atomic_long_set(wr_tx_id, val); +} + +/* post a new receive work request to fill a completed old work request entry */ +static inline int smc_wr_rx_post(struct smc_link *link) +{ + struct ib_recv_wr *bad_recv_wr = NULL; + int rc; + u64 wr_id, temp_wr_id; + u32 index; + + wr_id = ++link->wr_rx_id; /* tasklet context, thus not atomic */ + temp_wr_id = wr_id; + index = do_div(temp_wr_id, link->wr_rx_cnt); + link->wr_rx_ibs[index].wr_id = wr_id; + rc = ib_post_recv(link->roce_qp, &link->wr_rx_ibs[index], &bad_recv_wr); + return rc; +} + +int smc_wr_create_link(struct smc_link *lnk); +int smc_wr_alloc_link_mem(struct smc_link *lnk); +void smc_wr_free_link(struct smc_link *lnk); +void smc_wr_free_link_mem(struct smc_link *lnk); +void smc_wr_remember_qp_attr(struct smc_link *lnk); +void smc_wr_remove_dev(struct smc_ib_device *smcibdev); +void smc_wr_add_dev(struct smc_ib_device *smcibdev); + +int smc_wr_tx_get_free_slot(struct smc_link *link, smc_wr_tx_handler handler, + struct smc_wr_buf **wr_buf, + struct smc_wr_tx_pend_priv **wr_pend_priv); +int smc_wr_tx_put_slot(struct smc_link *link, + struct smc_wr_tx_pend_priv *wr_pend_priv); +int smc_wr_tx_send(struct smc_link *link, + struct smc_wr_tx_pend_priv *wr_pend_priv); +void smc_wr_tx_cq_handler(struct ib_cq *ib_cq, void *cq_context); + +int smc_wr_rx_register_handler(struct smc_wr_rx_handler *handler); +int smc_wr_rx_post_init(struct smc_link *link); +void smc_wr_rx_cq_handler(struct ib_cq *ib_cq, void *cq_context); + +#endif /* SMC_WR_H */ -- cgit