/* * Copyright (c) 2010, Oracle and/or its affiliates. All rights reserved. */ /* * This file contains code imported from the OFED rds source file ib_send.c * Oracle elects to have and use the contents of ib_send.c under and governed * by the OpenIB.org BSD license (see below for full license text). However, * the following notice accompanied the original version of this file: */ /* * Copyright (c) 2006 Oracle. All rights reserved. * * This software is available to you under a choice of one of two * licenses. You may choose to be licensed under the terms of the GNU * General Public License (GPL) Version 2, available from the file * COPYING in the main directory of this source tree, or the * OpenIB.org BSD license below: * * Redistribution and use in source and binary forms, with or * without modification, are permitted provided that the following * conditions are met: * * - Redistributions of source code must retain the above * copyright notice, this list of conditions and the following * disclaimer. * * - Redistributions in binary form must reproduce the above * copyright notice, this list of conditions and the following * disclaimer in the documentation and/or other materials * provided with the distribution. * * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE * SOFTWARE. * */ #include #include #include #include #include static void rdsv3_ib_send_rdma_complete(struct rdsv3_message *rm, int wc_status) { int notify_status; RDSV3_DPRINTF4("rdsv3_ib_send_rdma_complete", "rm: %p, wc_status: %d", rm, wc_status); switch (wc_status) { case IBT_WC_WR_FLUSHED_ERR: return; case IBT_WC_SUCCESS: notify_status = RDS_RDMA_SUCCESS; break; case IBT_WC_REMOTE_ACCESS_ERR: notify_status = RDS_RDMA_REMOTE_ERROR; break; default: notify_status = RDS_RDMA_OTHER_ERROR; break; } rdsv3_rdma_send_complete(rm, notify_status); RDSV3_DPRINTF4("rdsv3_ib_send_rdma_complete", "rm: %p, wc_status: %d", rm, wc_status); } static void rdsv3_ib_dma_unmap_sg_rdma(struct ib_device *dev, uint_t num, struct rdsv3_rdma_sg scat[]); void rdsv3_ib_send_unmap_rdma(struct rdsv3_ib_connection *ic, struct rdsv3_rdma_op *op) { RDSV3_DPRINTF4("rdsv3_ib_send_unmap_rdma", "ic: %p, op: %p", ic, op); if (op->r_mapped) { op->r_mapped = 0; if (ic->i_cm_id) { rdsv3_ib_dma_unmap_sg_rdma(ic->i_cm_id->device, op->r_nents, op->r_rdma_sg); } else { rdsv3_ib_dma_unmap_sg_rdma((struct ib_device *)NULL, op->r_nents, op->r_rdma_sg); } } } static void rdsv3_ib_send_unmap_rm(struct rdsv3_ib_connection *ic, struct rdsv3_ib_send_work *send, int wc_status) { struct rdsv3_message *rm = send->s_rm; RDSV3_DPRINTF4("rdsv3_ib_send_unmap_rm", "ic %p send %p rm %p\n", ic, send, rm); mutex_enter(&rm->m_rs_lock); if (rm->m_count) { rdsv3_ib_dma_unmap_sg(ic->i_cm_id->device, rm->m_sg, rm->m_count); rm->m_count = 0; } mutex_exit(&rm->m_rs_lock); if (rm->m_rdma_op != NULL) { rdsv3_ib_send_unmap_rdma(ic, rm->m_rdma_op); /* * If the user asked for a completion notification on this * message, we can implement three different semantics: * 1. Notify when we received the ACK on the RDS message * that was queued with the RDMA. This provides reliable * notification of RDMA status at the expense of a one-way * packet delay. * 2. Notify when the IB stack gives us the completion * event for the RDMA operation. * 3. Notify when the IB stack gives us the completion * event for the accompanying RDS messages. * Here, we implement approach #3. To implement approach #2, * call rdsv3_rdma_send_complete from the cq_handler. * To implement #1, * don't call rdsv3_rdma_send_complete at all, and fall back to * the notify * handling in the ACK processing code. * * Note: There's no need to explicitly sync any RDMA buffers * using * ib_dma_sync_sg_for_cpu - the completion for the RDMA * operation itself unmapped the RDMA buffers, which takes care * of synching. */ rdsv3_ib_send_rdma_complete(rm, wc_status); if (rm->m_rdma_op->r_write) rdsv3_stats_add(s_send_rdma_bytes, rm->m_rdma_op->r_bytes); else rdsv3_stats_add(s_recv_rdma_bytes, rm->m_rdma_op->r_bytes); } /* * If anyone waited for this message to get flushed out, wake * them up now */ rdsv3_message_unmapped(rm); rdsv3_message_put(rm); send->s_rm = NULL; } void rdsv3_ib_send_init_ring(struct rdsv3_ib_connection *ic) { struct rdsv3_ib_send_work *send; uint32_t i; RDSV3_DPRINTF4("rdsv3_ib_send_init_ring", "ic: %p", ic); for (i = 0, send = ic->i_sends; i < ic->i_send_ring.w_nr; i++, send++) { send->s_rm = NULL; send->s_op = NULL; } } void rdsv3_ib_send_clear_ring(struct rdsv3_ib_connection *ic) { struct rdsv3_ib_send_work *send; uint32_t i; RDSV3_DPRINTF4("rdsv3_ib_send_clear_ring", "ic: %p", ic); for (i = 0, send = ic->i_sends; i < ic->i_send_ring.w_nr; i++, send++) { if (send->s_opcode == 0xdd) continue; if (send->s_rm) rdsv3_ib_send_unmap_rm(ic, send, IBT_WC_WR_FLUSHED_ERR); if (send->s_op) rdsv3_ib_send_unmap_rdma(ic, send->s_op); } RDSV3_DPRINTF4("rdsv3_ib_send_clear_ring", "Return: ic: %p", ic); } /* * The _oldest/_free ring operations here race cleanly with the alloc/unalloc * operations performed in the send path. As the sender allocs and potentially * unallocs the next free entry in the ring it doesn't alter which is * the next to be freed, which is what this is concerned with. */ void rdsv3_ib_send_cqe_handler(struct rdsv3_ib_connection *ic, ibt_wc_t *wc) { struct rdsv3_connection *conn = ic->conn; struct rdsv3_ib_send_work *send; uint32_t completed, polled; uint32_t oldest; uint32_t i = 0; int ret; RDSV3_DPRINTF4("rdsv3_ib_send_cqe_handler", "wc wc_id 0x%llx status %u byte_len %u imm_data %u\n", (unsigned long long)wc->wc_id, wc->wc_status, wc->wc_bytes_xfer, ntohl(wc->wc_immed_data)); rdsv3_ib_stats_inc(s_ib_tx_cq_event); if (wc->wc_id == RDSV3_IB_ACK_WR_ID) { if (ic->i_ack_queued + HZ/2 < jiffies) rdsv3_ib_stats_inc(s_ib_tx_stalled); rdsv3_ib_ack_send_complete(ic); return; } oldest = rdsv3_ib_ring_oldest(&ic->i_send_ring); completed = rdsv3_ib_ring_completed(&ic->i_send_ring, (wc->wc_id & ~RDSV3_IB_SEND_OP), oldest); for (i = 0; i < completed; i++) { send = &ic->i_sends[oldest]; /* * In the error case, wc->opcode sometimes contains * garbage */ switch (send->s_opcode) { case IBT_WRC_SEND: if (send->s_rm) rdsv3_ib_send_unmap_rm(ic, send, wc->wc_status); break; case IBT_WRC_RDMAW: case IBT_WRC_RDMAR: /* * Nothing to be done - the SG list will * be unmapped * when the SEND completes. */ break; default: #ifndef __lock_lint RDSV3_DPRINTF2("rdsv3_ib_send_cq_comp_handler", "RDS/IB: %s: unexpected opcode " "0x%x in WR!", __func__, send->s_opcode); #endif break; } send->s_opcode = 0xdd; if (send->s_queued + HZ/2 < jiffies) rdsv3_ib_stats_inc(s_ib_tx_stalled); /* * If a RDMA operation produced an error, signal * this right * away. If we don't, the subsequent SEND that goes * with this * RDMA will be canceled with ERR_WFLUSH, and the * application * never learn that the RDMA failed. */ if (wc->wc_status == IBT_WC_REMOTE_ACCESS_ERR && send->s_op) { struct rdsv3_message *rm; rm = rdsv3_send_get_message(conn, send->s_op); if (rm) { if (rm->m_rdma_op != NULL) rdsv3_ib_send_unmap_rdma(ic, rm->m_rdma_op); rdsv3_ib_send_rdma_complete(rm, wc->wc_status); rdsv3_message_put(rm); } } oldest = (oldest + 1) % ic->i_send_ring.w_nr; } rdsv3_ib_ring_free(&ic->i_send_ring, completed); clear_bit(RDSV3_LL_SEND_FULL, &conn->c_flags); /* We expect errors as the qp is drained during shutdown */ if (wc->wc_status != IBT_WC_SUCCESS && rdsv3_conn_up(conn)) { RDSV3_DPRINTF2("rdsv3_ib_send_cqe_handler", "send completion on %u.%u.%u.%u " "had status %u, disconnecting and reconnecting\n", NIPQUAD(conn->c_faddr), wc->wc_status); rdsv3_conn_drop(conn); } RDSV3_DPRINTF4("rdsv3_ib_send_cqe_handler", "Return: conn: %p", ic); } /* * This is the main function for allocating credits when sending * messages. * * Conceptually, we have two counters: * - send credits: this tells us how many WRs we're allowed * to submit without overruning the reciever's queue. For * each SEND WR we post, we decrement this by one. * * - posted credits: this tells us how many WRs we recently * posted to the receive queue. This value is transferred * to the peer as a "credit update" in a RDS header field. * Every time we transmit credits to the peer, we subtract * the amount of transferred credits from this counter. * * It is essential that we avoid situations where both sides have * exhausted their send credits, and are unable to send new credits * to the peer. We achieve this by requiring that we send at least * one credit update to the peer before exhausting our credits. * When new credits arrive, we subtract one credit that is withheld * until we've posted new buffers and are ready to transmit these * credits (see rdsv3_ib_send_add_credits below). * * The RDS send code is essentially single-threaded; rdsv3_send_xmit * grabs c_send_lock to ensure exclusive access to the send ring. * However, the ACK sending code is independent and can race with * message SENDs. * * In the send path, we need to update the counters for send credits * and the counter of posted buffers atomically - when we use the * last available credit, we cannot allow another thread to race us * and grab the posted credits counter. Hence, we have to use a * spinlock to protect the credit counter, or use atomics. * * Spinlocks shared between the send and the receive path are bad, * because they create unnecessary delays. An early implementation * using a spinlock showed a 5% degradation in throughput at some * loads. * * This implementation avoids spinlocks completely, putting both * counters into a single atomic, and updating that atomic using * atomic_add (in the receive path, when receiving fresh credits), * and using atomic_cmpxchg when updating the two counters. */ int rdsv3_ib_send_grab_credits(struct rdsv3_ib_connection *ic, uint32_t wanted, uint32_t *adv_credits, int need_posted) { unsigned int avail, posted, got = 0, advertise; long oldval, newval; RDSV3_DPRINTF4("rdsv3_ib_send_grab_credits", "ic: %p, %d %d %d", ic, wanted, *adv_credits, need_posted); *adv_credits = 0; if (!ic->i_flowctl) return (wanted); try_again: advertise = 0; oldval = newval = atomic_get(&ic->i_credits); posted = IB_GET_POST_CREDITS(oldval); avail = IB_GET_SEND_CREDITS(oldval); RDSV3_DPRINTF5("rdsv3_ib_send_grab_credits", "wanted (%u): credits=%u posted=%u\n", wanted, avail, posted); /* The last credit must be used to send a credit update. */ if (avail && !posted) avail--; if (avail < wanted) { struct rdsv3_connection *conn = ic->i_cm_id->context; /* Oops, there aren't that many credits left! */ set_bit(RDSV3_LL_SEND_FULL, &conn->c_flags); got = avail; } else { /* Sometimes you get what you want, lalala. */ got = wanted; } newval -= IB_SET_SEND_CREDITS(got); /* * If need_posted is non-zero, then the caller wants * the posted regardless of whether any send credits are * available. */ if (posted && (got || need_posted)) { advertise = min(posted, RDSV3_MAX_ADV_CREDIT); newval -= IB_SET_POST_CREDITS(advertise); } /* Finally bill everything */ if (atomic_cmpxchg(&ic->i_credits, oldval, newval) != oldval) goto try_again; *adv_credits = advertise; RDSV3_DPRINTF4("rdsv3_ib_send_grab_credits", "ic: %p, %d %d %d", ic, got, *adv_credits, need_posted); return (got); } void rdsv3_ib_send_add_credits(struct rdsv3_connection *conn, unsigned int credits) { struct rdsv3_ib_connection *ic = conn->c_transport_data; if (credits == 0) return; RDSV3_DPRINTF5("rdsv3_ib_send_add_credits", "credits (%u): current=%u%s\n", credits, IB_GET_SEND_CREDITS(atomic_get(&ic->i_credits)), test_bit(RDSV3_LL_SEND_FULL, &conn->c_flags) ? ", ll_send_full" : ""); atomic_add_32(&ic->i_credits, IB_SET_SEND_CREDITS(credits)); if (test_and_clear_bit(RDSV3_LL_SEND_FULL, &conn->c_flags)) rdsv3_queue_delayed_work(rdsv3_wq, &conn->c_send_w, 0); ASSERT(!(IB_GET_SEND_CREDITS(credits) >= 16384)); rdsv3_ib_stats_inc(s_ib_rx_credit_updates); RDSV3_DPRINTF4("rdsv3_ib_send_add_credits", "Return: conn: %p, credits: %d", conn, credits); } void rdsv3_ib_advertise_credits(struct rdsv3_connection *conn, unsigned int posted) { struct rdsv3_ib_connection *ic = conn->c_transport_data; RDSV3_DPRINTF4("rdsv3_ib_advertise_credits", "conn: %p, posted: %d", conn, posted); if (posted == 0) return; atomic_add_32(&ic->i_credits, IB_SET_POST_CREDITS(posted)); /* * Decide whether to send an update to the peer now. * If we would send a credit update for every single buffer we * post, we would end up with an ACK storm (ACK arrives, * consumes buffer, we refill the ring, send ACK to remote * advertising the newly posted buffer... ad inf) * * Performance pretty much depends on how often we send * credit updates - too frequent updates mean lots of ACKs. * Too infrequent updates, and the peer will run out of * credits and has to throttle. * For the time being, 16 seems to be a good compromise. */ if (IB_GET_POST_CREDITS(atomic_get(&ic->i_credits)) >= 16) set_bit(IB_ACK_REQUESTED, &ic->i_ack_flags); } static inline void rdsv3_ib_xmit_populate_wr(struct rdsv3_ib_connection *ic, ibt_send_wr_t *wr, unsigned int pos, struct rdsv3_scatterlist *scat, unsigned int off, unsigned int length, int send_flags) { ibt_wr_ds_t *sge; RDSV3_DPRINTF4("rdsv3_ib_xmit_populate_wr", "ic: %p, wr: %p scat: %p %d %d %d %d", ic, wr, scat, pos, off, length, send_flags); wr->wr_id = pos | RDSV3_IB_SEND_OP; wr->wr_trans = IBT_RC_SRV; wr->wr_flags = send_flags; wr->wr_opcode = IBT_WRC_SEND; if (length != 0) { int ix, len, assigned; ibt_wr_ds_t *sgl; ASSERT(length <= scat->length - off); sgl = scat->sgl; if (off != 0) { /* find the right sgl to begin with */ while (sgl->ds_len <= off) { off -= sgl->ds_len; sgl++; } } ix = 1; /* first data sgl is at 1 */ assigned = 0; len = length; do { sge = &wr->wr_sgl[ix++]; sge->ds_va = sgl->ds_va + off; assigned = min(len, sgl->ds_len - off); sge->ds_len = assigned; sge->ds_key = sgl->ds_key; len -= assigned; if (len != 0) { sgl++; off = 0; } } while (len > 0); wr->wr_nds = ix; } else { /* * We're sending a packet with no payload. There is only * one SGE */ wr->wr_nds = 1; } sge = &wr->wr_sgl[0]; sge->ds_va = ic->i_send_hdrs_dma + (pos * sizeof (struct rdsv3_header)); sge->ds_len = sizeof (struct rdsv3_header); sge->ds_key = ic->i_mr->lkey; RDSV3_DPRINTF4("rdsv3_ib_xmit_populate_wr", "Return: ic: %p, wr: %p scat: %p", ic, wr, scat); } /* * This can be called multiple times for a given message. The first time * we see a message we map its scatterlist into the IB device so that * we can provide that mapped address to the IB scatter gather entries * in the IB work requests. We translate the scatterlist into a series * of work requests that fragment the message. These work requests complete * in order so we pass ownership of the message to the completion handler * once we send the final fragment. * * The RDS core uses the c_send_lock to only enter this function once * per connection. This makes sure that the tx ring alloc/unalloc pairs * don't get out of sync and confuse the ring. */ int rdsv3_ib_xmit(struct rdsv3_connection *conn, struct rdsv3_message *rm, unsigned int hdr_off, unsigned int sg, unsigned int off) { struct rdsv3_ib_connection *ic = conn->c_transport_data; struct ib_device *dev = ic->i_cm_id->device; struct rdsv3_ib_send_work *send = NULL; struct rdsv3_ib_send_work *first; struct rdsv3_ib_send_work *prev; ibt_send_wr_t *wr; struct rdsv3_scatterlist *scat; uint32_t pos; uint32_t i; uint32_t work_alloc; uint32_t credit_alloc; uint32_t posted; uint32_t adv_credits = 0; int send_flags = 0; int sent; int ret; int flow_controlled = 0; RDSV3_DPRINTF4("rdsv3_ib_xmit", "conn: %p, rm: %p", conn, rm); ASSERT(!(off % RDSV3_FRAG_SIZE)); ASSERT(!(hdr_off != 0 && hdr_off != sizeof (struct rdsv3_header))); /* Do not send cong updates to IB loopback */ if (conn->c_loopback && rm->m_inc.i_hdr.h_flags & RDSV3_FLAG_CONG_BITMAP) { rdsv3_cong_map_updated(conn->c_fcong, ~(uint64_t)0); return (sizeof (struct rdsv3_header) + RDSV3_CONG_MAP_BYTES); } #ifndef __lock_lint /* FIXME we may overallocate here */ if (ntohl(rm->m_inc.i_hdr.h_len) == 0) i = 1; else i = ceil(ntohl(rm->m_inc.i_hdr.h_len), RDSV3_FRAG_SIZE); #endif work_alloc = rdsv3_ib_ring_alloc(&ic->i_send_ring, i, &pos); if (work_alloc != i) { rdsv3_ib_ring_unalloc(&ic->i_send_ring, work_alloc); set_bit(RDSV3_LL_SEND_FULL, &conn->c_flags); rdsv3_ib_stats_inc(s_ib_tx_ring_full); ret = -ENOMEM; goto out; } credit_alloc = work_alloc; if (ic->i_flowctl) { credit_alloc = rdsv3_ib_send_grab_credits(ic, work_alloc, &posted, 0); adv_credits += posted; if (credit_alloc < work_alloc) { rdsv3_ib_ring_unalloc(&ic->i_send_ring, work_alloc - credit_alloc); work_alloc = credit_alloc; flow_controlled++; } if (work_alloc == 0) { rdsv3_ib_ring_unalloc(&ic->i_send_ring, work_alloc); rdsv3_ib_stats_inc(s_ib_tx_throttle); ret = -ENOMEM; goto out; } } /* map the message the first time we see it */ if (ic->i_rm == NULL) { /* * printk(KERN_NOTICE * "rdsv3_ib_xmit prep msg dport=%u flags=0x%x len=%d\n", * be16_to_cpu(rm->m_inc.i_hdr.h_dport), * rm->m_inc.i_hdr.h_flags, * be32_to_cpu(rm->m_inc.i_hdr.h_len)); */ if (rm->m_nents) { rm->m_count = rdsv3_ib_dma_map_sg(dev, rm->m_sg, rm->m_nents); RDSV3_DPRINTF5("rdsv3_ib_xmit", "ic %p mapping rm %p: %d\n", ic, rm, rm->m_count); if (rm->m_count == 0) { rdsv3_ib_stats_inc(s_ib_tx_sg_mapping_failure); rdsv3_ib_ring_unalloc(&ic->i_send_ring, work_alloc); ret = -ENOMEM; /* XXX ? */ RDSV3_DPRINTF2("rdsv3_ib_xmit", "fail: ic %p mapping rm %p: %d\n", ic, rm, rm->m_count); goto out; } } else { rm->m_count = 0; } ic->i_unsignaled_wrs = rdsv3_ib_sysctl_max_unsig_wrs; ic->i_unsignaled_bytes = rdsv3_ib_sysctl_max_unsig_bytes; rdsv3_message_addref(rm); ic->i_rm = rm; /* Finalize the header */ if (test_bit(RDSV3_MSG_ACK_REQUIRED, &rm->m_flags)) rm->m_inc.i_hdr.h_flags |= RDSV3_FLAG_ACK_REQUIRED; if (test_bit(RDSV3_MSG_RETRANSMITTED, &rm->m_flags)) rm->m_inc.i_hdr.h_flags |= RDSV3_FLAG_RETRANSMITTED; /* * If it has a RDMA op, tell the peer we did it. This is * used by the peer to release use-once RDMA MRs. */ if (rm->m_rdma_op) { struct rdsv3_ext_header_rdma ext_hdr; ext_hdr.h_rdma_rkey = htonl(rm->m_rdma_op->r_key); (void) rdsv3_message_add_extension(&rm->m_inc.i_hdr, RDSV3_EXTHDR_RDMA, &ext_hdr, sizeof (ext_hdr)); } if (rm->m_rdma_cookie) { (void) rdsv3_message_add_rdma_dest_extension( &rm->m_inc.i_hdr, rdsv3_rdma_cookie_key(rm->m_rdma_cookie), rdsv3_rdma_cookie_offset(rm->m_rdma_cookie)); } /* * Note - rdsv3_ib_piggyb_ack clears the ACK_REQUIRED bit, so * we should not do this unless we have a chance of at least * sticking the header into the send ring. Which is why we * should call rdsv3_ib_ring_alloc first. */ rm->m_inc.i_hdr.h_ack = htonll(rdsv3_ib_piggyb_ack(ic)); rdsv3_message_make_checksum(&rm->m_inc.i_hdr); /* * Update adv_credits since we reset the ACK_REQUIRED bit. */ (void) rdsv3_ib_send_grab_credits(ic, 0, &posted, 1); adv_credits += posted; ASSERT(adv_credits <= 255); } send = &ic->i_sends[pos]; first = send; prev = NULL; scat = &rm->m_sg[sg]; sent = 0; i = 0; /* * Sometimes you want to put a fence between an RDMA * READ and the following SEND. * We could either do this all the time * or when requested by the user. Right now, we let * the application choose. */ if (rm->m_rdma_op && rm->m_rdma_op->r_fence) send_flags = IBT_WR_SEND_FENCE; /* * We could be copying the header into the unused tail of the page. * That would need to be changed in the future when those pages might * be mapped userspace pages or page cache pages. So instead we always * use a second sge and our long-lived ring of mapped headers. We send * the header after the data so that the data payload can be aligned on * the receiver. */ /* handle a 0-len message */ if (ntohl(rm->m_inc.i_hdr.h_len) == 0) { wr = &ic->i_send_wrs[0]; rdsv3_ib_xmit_populate_wr(ic, wr, pos, NULL, 0, 0, send_flags); send->s_queued = jiffies; send->s_op = NULL; send->s_opcode = wr->wr_opcode; goto add_header; } /* if there's data reference it with a chain of work reqs */ for (; i < work_alloc && scat != &rm->m_sg[rm->m_count]; i++) { unsigned int len; send = &ic->i_sends[pos]; wr = &ic->i_send_wrs[i]; len = min(RDSV3_FRAG_SIZE, rdsv3_ib_sg_dma_len(dev, scat) - off); rdsv3_ib_xmit_populate_wr(ic, wr, pos, scat, off, len, send_flags); send->s_queued = jiffies; send->s_op = NULL; send->s_opcode = wr->wr_opcode; /* * We want to delay signaling completions just enough to get * the batching benefits but not so much that we create dead * time * on the wire. */ if (ic->i_unsignaled_wrs-- == 0) { ic->i_unsignaled_wrs = rdsv3_ib_sysctl_max_unsig_wrs; wr->wr_flags |= IBT_WR_SEND_SIGNAL | IBT_WR_SEND_SOLICIT; } ic->i_unsignaled_bytes -= len; if (ic->i_unsignaled_bytes <= 0) { ic->i_unsignaled_bytes = rdsv3_ib_sysctl_max_unsig_bytes; wr->wr_flags |= IBT_WR_SEND_SIGNAL | IBT_WR_SEND_SOLICIT; } /* * Always signal the last one if we're stopping due to flow * control. */ if (flow_controlled && i == (work_alloc-1)) { wr->wr_flags |= IBT_WR_SEND_SIGNAL | IBT_WR_SEND_SOLICIT; } RDSV3_DPRINTF5("rdsv3_ib_xmit", "send %p wr %p num_sge %u \n", send, wr, wr->wr_nds); sent += len; off += len; if (off == rdsv3_ib_sg_dma_len(dev, scat)) { scat++; off = 0; } add_header: /* * Tack on the header after the data. The header SGE * should already * have been set up to point to the right header buffer. */ (void) memcpy(&ic->i_send_hdrs[pos], &rm->m_inc.i_hdr, sizeof (struct rdsv3_header)); if (0) { struct rdsv3_header *hdr = &ic->i_send_hdrs[pos]; RDSV3_DPRINTF2("rdsv3_ib_xmit", "send WR dport=%u flags=0x%x len=%d", ntohs(hdr->h_dport), hdr->h_flags, ntohl(hdr->h_len)); } if (adv_credits) { struct rdsv3_header *hdr = &ic->i_send_hdrs[pos]; /* add credit and redo the header checksum */ hdr->h_credit = adv_credits; rdsv3_message_make_checksum(hdr); adv_credits = 0; rdsv3_ib_stats_inc(s_ib_tx_credit_updates); } prev = send; pos = (pos + 1) % ic->i_send_ring.w_nr; } /* * Account the RDS header in the number of bytes we sent, but just once. * The caller has no concept of fragmentation. */ if (hdr_off == 0) sent += sizeof (struct rdsv3_header); /* if we finished the message then send completion owns it */ if (scat == &rm->m_sg[rm->m_count]) { prev->s_rm = ic->i_rm; wr->wr_flags |= IBT_WR_SEND_SIGNAL | IBT_WR_SEND_SOLICIT; ic->i_rm = NULL; } if (i < work_alloc) { rdsv3_ib_ring_unalloc(&ic->i_send_ring, work_alloc - i); work_alloc = i; } if (ic->i_flowctl && i < credit_alloc) rdsv3_ib_send_add_credits(conn, credit_alloc - i); /* XXX need to worry about failed_wr and partial sends. */ ret = ibt_post_send(ib_get_ibt_channel_hdl(ic->i_cm_id), ic->i_send_wrs, i, &posted); if (posted != i) { RDSV3_DPRINTF2("rdsv3_ib_xmit", "ic %p first %p nwr: %d ret %d:%d", ic, first, i, ret, posted); } if (ret) { RDSV3_DPRINTF2("rdsv3_ib_xmit", "RDS/IB: ib_post_send to %u.%u.%u.%u " "returned %d\n", NIPQUAD(conn->c_faddr), ret); rdsv3_ib_ring_unalloc(&ic->i_send_ring, work_alloc); if (prev->s_rm) { ic->i_rm = prev->s_rm; prev->s_rm = NULL; } RDSV3_DPRINTF2("rdsv3_ib_xmit", "ibt_post_send failed\n"); rdsv3_conn_drop(ic->conn); ret = -EAGAIN; goto out; } ret = sent; RDSV3_DPRINTF4("rdsv3_ib_xmit", "Return: conn: %p, rm: %p", conn, rm); out: ASSERT(!adv_credits); return (ret); } static void rdsv3_ib_dma_unmap_sg_rdma(struct ib_device *dev, uint_t num, struct rdsv3_rdma_sg scat[]) { ibt_hca_hdl_t hca_hdl; int i; int num_sgl; RDSV3_DPRINTF4("rdsv3_ib_dma_unmap_sg", "rdma_sg: %p", scat); if (dev) { hca_hdl = ib_get_ibt_hca_hdl(dev); } else { hca_hdl = scat[0].hca_hdl; RDSV3_DPRINTF2("rdsv3_ib_dma_unmap_sg_rdma", "NULL dev use cached hca_hdl %p", hca_hdl); } if (hca_hdl == NULL) return; scat[0].hca_hdl = NULL; for (i = 0; i < num; i++) { if (scat[i].mihdl != NULL) { num_sgl = (scat[i].iovec.bytes / PAGESIZE) + 2; kmem_free(scat[i].swr.wr_sgl, (num_sgl * sizeof (ibt_wr_ds_t))); scat[i].swr.wr_sgl = NULL; (void) ibt_unmap_mem_iov(hca_hdl, scat[i].mihdl); scat[i].mihdl = NULL; } else break; } } /* ARGSUSED */ uint_t rdsv3_ib_dma_map_sg_rdma(struct ib_device *dev, struct rdsv3_rdma_sg scat[], uint_t num, struct rdsv3_scatterlist **scatl) { ibt_hca_hdl_t hca_hdl; ibt_iov_attr_t iov_attr; struct buf *bp; uint_t i, j, k; uint_t count; struct rdsv3_scatterlist *sg; int ret; RDSV3_DPRINTF4("rdsv3_ib_dma_map_sg_rdma", "scat: %p, num: %d", scat, num); hca_hdl = ib_get_ibt_hca_hdl(dev); scat[0].hca_hdl = hca_hdl; bzero(&iov_attr, sizeof (ibt_iov_attr_t)); iov_attr.iov_flags = IBT_IOV_BUF; iov_attr.iov_lso_hdr_sz = 0; for (i = 0, count = 0; i < num; i++) { /* transpose umem_cookie to buf structure */ bp = ddi_umem_iosetup(scat[i].umem_cookie, scat[i].iovec.addr & PAGEOFFSET, scat[i].iovec.bytes, B_WRITE, 0, 0, NULL, DDI_UMEM_SLEEP); if (bp == NULL) { /* free resources and return error */ goto out; } /* setup ibt_map_mem_iov() attributes */ iov_attr.iov_buf = bp; iov_attr.iov_wr_nds = (scat[i].iovec.bytes / PAGESIZE) + 2; scat[i].swr.wr_sgl = kmem_zalloc(iov_attr.iov_wr_nds * sizeof (ibt_wr_ds_t), KM_SLEEP); ret = ibt_map_mem_iov(hca_hdl, &iov_attr, (ibt_all_wr_t *)&scat[i].swr, &scat[i].mihdl); freerbuf(bp); if (ret != IBT_SUCCESS) { RDSV3_DPRINTF2("rdsv3_ib_dma_map_sg_rdma", "ibt_map_mem_iov returned: %d", ret); /* free resources and return error */ kmem_free(scat[i].swr.wr_sgl, iov_attr.iov_wr_nds * sizeof (ibt_wr_ds_t)); goto out; } count += scat[i].swr.wr_nds; #ifdef DEBUG for (j = 0; j < scat[i].swr.wr_nds; j++) { RDSV3_DPRINTF5("rdsv3_ib_dma_map_sg_rdma", "sgl[%d] va %llx len %x", j, scat[i].swr.wr_sgl[j].ds_va, scat[i].swr.wr_sgl[j].ds_len); } #endif RDSV3_DPRINTF4("rdsv3_ib_dma_map_sg_rdma", "iovec.bytes: 0x%x scat[%d]swr.wr_nds: %d", scat[i].iovec.bytes, i, scat[i].swr.wr_nds); } count = ((count - 1) / RDSV3_IB_MAX_SGE) + 1; RDSV3_DPRINTF4("rdsv3_ib_dma_map_sg_rdma", "Ret: num: %d", count); return (count); out: rdsv3_ib_dma_unmap_sg_rdma(dev, num, scat); return (0); } int rdsv3_ib_xmit_rdma(struct rdsv3_connection *conn, struct rdsv3_rdma_op *op) { struct rdsv3_ib_connection *ic = conn->c_transport_data; struct rdsv3_ib_send_work *send = NULL; struct rdsv3_rdma_sg *scat; uint64_t remote_addr; uint32_t pos; uint32_t work_alloc; uint32_t i, j, k, idx; uint32_t left, count; uint32_t posted; int sent; ibt_status_t status; ibt_send_wr_t *wr; ibt_wr_ds_t *sge; RDSV3_DPRINTF4("rdsv3_ib_xmit_rdma", "rdsv3_ib_conn: %p", ic); /* map the message the first time we see it */ if (!op->r_mapped) { op->r_count = rdsv3_ib_dma_map_sg_rdma(ic->i_cm_id->device, op->r_rdma_sg, op->r_nents, &op->r_sg); RDSV3_DPRINTF5("rdsv3_ib_xmit_rdma", "ic %p mapping op %p: %d", ic, op, op->r_count); if (op->r_count == 0) { rdsv3_ib_stats_inc(s_ib_tx_sg_mapping_failure); RDSV3_DPRINTF2("rdsv3_ib_xmit_rdma", "fail: ic %p mapping op %p: %d", ic, op, op->r_count); return (-ENOMEM); /* XXX ? */ } op->r_mapped = 1; } /* * Instead of knowing how to return a partial rdma read/write * we insist that there * be enough work requests to send the entire message. */ work_alloc = rdsv3_ib_ring_alloc(&ic->i_send_ring, op->r_count, &pos); if (work_alloc != op->r_count) { rdsv3_ib_ring_unalloc(&ic->i_send_ring, work_alloc); rdsv3_ib_stats_inc(s_ib_tx_ring_full); return (-ENOMEM); } RDSV3_DPRINTF4("rdsv3_ib_xmit_rdma", "pos %u cnt %u", pos, op->r_count); /* * take the scatter list and transpose into a list of * send wr's each with a scatter list of RDSV3_IB_MAX_SGE */ scat = &op->r_rdma_sg[0]; sent = 0; remote_addr = op->r_remote_addr; for (i = 0, k = 0; i < op->r_nents; i++) { left = scat[i].swr.wr_nds; for (idx = 0; left > 0; k++) { send = &ic->i_sends[pos]; send->s_queued = jiffies; send->s_opcode = op->r_write ? IBT_WRC_RDMAW : IBT_WRC_RDMAR; send->s_op = op; wr = &ic->i_send_wrs[k]; wr->wr_flags = 0; wr->wr_id = pos | RDSV3_IB_SEND_OP; wr->wr_trans = IBT_RC_SRV; wr->wr_opcode = op->r_write ? IBT_WRC_RDMAW : IBT_WRC_RDMAR; wr->wr.rc.rcwr.rdma.rdma_raddr = remote_addr; wr->wr.rc.rcwr.rdma.rdma_rkey = op->r_key; if (left > RDSV3_IB_MAX_SGE) { count = RDSV3_IB_MAX_SGE; left -= RDSV3_IB_MAX_SGE; } else { count = left; left = 0; } wr->wr_nds = count; for (j = 0; j < count; j++) { sge = &wr->wr_sgl[j]; *sge = scat[i].swr.wr_sgl[idx]; remote_addr += scat[i].swr.wr_sgl[idx].ds_len; sent += scat[i].swr.wr_sgl[idx].ds_len; idx++; RDSV3_DPRINTF5("xmit_rdma", "send_wrs[%d]sgl[%d] va %llx len %x", k, j, sge->ds_va, sge->ds_len); } RDSV3_DPRINTF5("rdsv3_ib_xmit_rdma", "wr[%d] %p key: %x code: %d tlen: %d", k, wr, wr->wr.rc.rcwr.rdma.rdma_rkey, wr->wr_opcode, sent); /* * We want to delay signaling completions just enough * to get the batching benefits but not so much that * we create dead time on the wire. */ if (ic->i_unsignaled_wrs-- == 0) { ic->i_unsignaled_wrs = rdsv3_ib_sysctl_max_unsig_wrs; wr->wr_flags = IBT_WR_SEND_SIGNAL; } pos = (pos + 1) % ic->i_send_ring.w_nr; } } status = ibt_post_send(ib_get_ibt_channel_hdl(ic->i_cm_id), ic->i_send_wrs, k, &posted); if (status != IBT_SUCCESS) { RDSV3_DPRINTF2("rdsv3_ib_xmit_rdma", "RDS/IB: rdma ib_post_send to %u.%u.%u.%u " "returned %d", NIPQUAD(conn->c_faddr), status); rdsv3_ib_ring_unalloc(&ic->i_send_ring, work_alloc); } RDSV3_DPRINTF4("rdsv3_ib_xmit_rdma", "Ret: %p", ic); return (status); } void rdsv3_ib_xmit_complete(struct rdsv3_connection *conn) { struct rdsv3_ib_connection *ic = conn->c_transport_data; RDSV3_DPRINTF4("rdsv3_ib_xmit_complete", "conn: %p", conn); /* * We may have a pending ACK or window update we were unable * to send previously (due to flow control). Try again. */ rdsv3_ib_attempt_ack(ic); }