/* * Copyright (c) 2006, 2007, 2008 QLogic Corporation. All rights reserved. * Copyright (c) 2005, 2006 PathScale, Inc. 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 "ipath_verbs.h" #include "ipath_kernel.h" /* cut down ridiculously long IB macro names */ #define OP(x) IB_OPCODE_RC_##x static u32 restart_sge(struct ipath_sge_state *ss, struct ipath_swqe *wqe, u32 psn, u32 pmtu) { u32 len; len = ((psn - wqe->psn) & IPATH_PSN_MASK) * pmtu; ss->sge = wqe->sg_list[0]; ss->sg_list = wqe->sg_list + 1; ss->num_sge = wqe->wr.num_sge; ipath_skip_sge(ss, len); return wqe->length - len; } /** * ipath_init_restart- initialize the qp->s_sge after a restart * @qp: the QP who's SGE we're restarting * @wqe: the work queue to initialize the QP's SGE from * * The QP s_lock should be held and interrupts disabled. */ static void ipath_init_restart(struct ipath_qp *qp, struct ipath_swqe *wqe) { struct ipath_ibdev *dev; qp->s_len = restart_sge(&qp->s_sge, wqe, qp->s_psn, ib_mtu_enum_to_int(qp->path_mtu)); dev = to_idev(qp->ibqp.device); spin_lock(&dev->pending_lock); if (list_empty(&qp->timerwait)) list_add_tail(&qp->timerwait, &dev->pending[dev->pending_index]); spin_unlock(&dev->pending_lock); } /** * ipath_make_rc_ack - construct a response packet (ACK, NAK, or RDMA read) * @qp: a pointer to the QP * @ohdr: a pointer to the IB header being constructed * @pmtu: the path MTU * * Return 1 if constructed; otherwise, return 0. * Note that we are in the responder's side of the QP context. * Note the QP s_lock must be held. */ static int ipath_make_rc_ack(struct ipath_ibdev *dev, struct ipath_qp *qp, struct ipath_other_headers *ohdr, u32 pmtu) { struct ipath_ack_entry *e; u32 hwords; u32 len; u32 bth0; u32 bth2; /* header size in 32-bit words LRH+BTH = (8+12)/4. */ hwords = 5; switch (qp->s_ack_state) { case OP(RDMA_READ_RESPONSE_LAST): case OP(RDMA_READ_RESPONSE_ONLY): case OP(ATOMIC_ACKNOWLEDGE): /* * We can increment the tail pointer now that the last * response has been sent instead of only being * constructed. */ if (++qp->s_tail_ack_queue > IPATH_MAX_RDMA_ATOMIC) qp->s_tail_ack_queue = 0; /* FALLTHROUGH */ case OP(SEND_ONLY): case OP(ACKNOWLEDGE): /* Check for no next entry in the queue. */ if (qp->r_head_ack_queue == qp->s_tail_ack_queue) { if (qp->s_flags & IPATH_S_ACK_PENDING) goto normal; qp->s_ack_state = OP(ACKNOWLEDGE); goto bail; } e = &qp->s_ack_queue[qp->s_tail_ack_queue]; if (e->opcode == OP(RDMA_READ_REQUEST)) { /* Copy SGE state in case we need to resend */ qp->s_ack_rdma_sge = e->rdma_sge; qp->s_cur_sge = &qp->s_ack_rdma_sge; len = e->rdma_sge.sge.sge_length; if (len > pmtu) { len = pmtu; qp->s_ack_state = OP(RDMA_READ_RESPONSE_FIRST); } else { qp->s_ack_state = OP(RDMA_READ_RESPONSE_ONLY); e->sent = 1; } ohdr->u.aeth = ipath_compute_aeth(qp); hwords++; qp->s_ack_rdma_psn = e->psn; bth2 = qp->s_ack_rdma_psn++ & IPATH_PSN_MASK; } else { /* COMPARE_SWAP or FETCH_ADD */ qp->s_cur_sge = NULL; len = 0; qp->s_ack_state = OP(ATOMIC_ACKNOWLEDGE); ohdr->u.at.aeth = ipath_compute_aeth(qp); ohdr->u.at.atomic_ack_eth[0] = cpu_to_be32(e->atomic_data >> 32); ohdr->u.at.atomic_ack_eth[1] = cpu_to_be32(e->atomic_data); hwords += sizeof(ohdr->u.at) / sizeof(u32); bth2 = e->psn; e->sent = 1; } bth0 = qp->s_ack_state << 24; break; case OP(RDMA_READ_RESPONSE_FIRST): qp->s_ack_state = OP(RDMA_READ_RESPONSE_MIDDLE); /* FALLTHROUGH */ case OP(RDMA_READ_RESPONSE_MIDDLE): len = qp->s_ack_rdma_sge.sge.sge_length; if (len > pmtu) len = pmtu; else { ohdr->u.aeth = ipath_compute_aeth(qp); hwords++; qp->s_ack_state = OP(RDMA_READ_RESPONSE_LAST); qp->s_ack_queue[qp->s_tail_ack_queue].sent = 1; } bth0 = qp->s_ack_state << 24; bth2 = qp->s_ack_rdma_psn++ & IPATH_PSN_MASK; break; default: normal: /* * Send a regular ACK. * Set the s_ack_state so we wait until after sending * the ACK before setting s_ack_state to ACKNOWLEDGE * (see above). */ qp->s_ack_state = OP(SEND_ONLY); qp->s_flags &= ~IPATH_S_ACK_PENDING; qp->s_cur_sge = NULL; if (qp->s_nak_state) ohdr->u.aeth = cpu_to_be32((qp->r_msn & IPATH_MSN_MASK) | (qp->s_nak_state << IPATH_AETH_CREDIT_SHIFT)); else ohdr->u.aeth = ipath_compute_aeth(qp); hwords++; len = 0; bth0 = OP(ACKNOWLEDGE) << 24; bth2 = qp->s_ack_psn & IPATH_PSN_MASK; } qp->s_hdrwords = hwords; qp->s_cur_size = len; ipath_make_ruc_header(dev, qp, ohdr, bth0, bth2); return 1; bail: return 0; } /** * ipath_make_rc_req - construct a request packet (SEND, RDMA r/w, ATOMIC) * @qp: a pointer to the QP * * Return 1 if constructed; otherwise, return 0. */ int ipath_make_rc_req(struct ipath_qp *qp) { struct ipath_ibdev *dev = to_idev(qp->ibqp.device); struct ipath_other_headers *ohdr; struct ipath_sge_state *ss; struct ipath_swqe *wqe; u32 hwords; u32 len; u32 bth0; u32 bth2; u32 pmtu = ib_mtu_enum_to_int(qp->path_mtu); char newreq; unsigned long flags; int ret = 0; ohdr = &qp->s_hdr.u.oth; if (qp->remote_ah_attr.ah_flags & IB_AH_GRH) ohdr = &qp->s_hdr.u.l.oth; /* * The lock is needed to synchronize between the sending tasklet, * the receive interrupt handler, and timeout resends. */ spin_lock_irqsave(&qp->s_lock, flags); /* Sending responses has higher priority over sending requests. */ if ((qp->r_head_ack_queue != qp->s_tail_ack_queue || (qp->s_flags & IPATH_S_ACK_PENDING) || qp->s_ack_state != OP(ACKNOWLEDGE)) && ipath_make_rc_ack(dev, qp, ohdr, pmtu)) goto done; if (!(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_SEND_OK) || qp->s_rnr_timeout || qp->s_wait_credit) goto bail; /* Limit the number of packets sent without an ACK. */ if (ipath_cmp24(qp->s_psn, qp->s_last_psn + IPATH_PSN_CREDIT) > 0) { qp->s_wait_credit = 1; dev->n_rc_stalls++; goto bail; } /* header size in 32-bit words LRH+BTH = (8+12)/4. */ hwords = 5; bth0 = 1 << 22; /* Set M bit */ /* Send a request. */ wqe = get_swqe_ptr(qp, qp->s_cur); switch (qp->s_state) { default: /* * Resend an old request or start a new one. * * We keep track of the current SWQE so that * we don't reset the "furthest progress" state * if we need to back up. */ newreq = 0; if (qp->s_cur == qp->s_tail) { /* Check if send work queue is empty. */ if (qp->s_tail == qp->s_head) goto bail; /* * If a fence is requested, wait for previous * RDMA read and atomic operations to finish. */ if ((wqe->wr.send_flags & IB_SEND_FENCE) && qp->s_num_rd_atomic) { qp->s_flags |= IPATH_S_FENCE_PENDING; goto bail; } wqe->psn = qp->s_next_psn; newreq = 1; } /* * Note that we have to be careful not to modify the * original work request since we may need to resend * it. */ len = wqe->length; ss = &qp->s_sge; bth2 = 0; switch (wqe->wr.opcode) { case IB_WR_SEND: case IB_WR_SEND_WITH_IMM: /* If no credit, return. */ if (qp->s_lsn != (u32) -1 && ipath_cmp24(wqe->ssn, qp->s_lsn + 1) > 0) goto bail; wqe->lpsn = wqe->psn; if (len > pmtu) { wqe->lpsn += (len - 1) / pmtu; qp->s_state = OP(SEND_FIRST); len = pmtu; break; } if (wqe->wr.opcode == IB_WR_SEND) qp->s_state = OP(SEND_ONLY); else { qp->s_state = OP(SEND_ONLY_WITH_IMMEDIATE); /* Immediate data comes after the BTH */ ohdr->u.imm_data = wqe->wr.ex.imm_data; hwords += 1; } if (wqe->wr.send_flags & IB_SEND_SOLICITED) bth0 |= 1 << 23; bth2 = 1 << 31; /* Request ACK. */ if (++qp->s_cur == qp->s_size) qp->s_cur = 0; break; case IB_WR_RDMA_WRITE: if (newreq && qp->s_lsn != (u32) -1) qp->s_lsn++; /* FALLTHROUGH */ case IB_WR_RDMA_WRITE_WITH_IMM: /* If no credit, return. */ if (qp->s_lsn != (u32) -1 && ipath_cmp24(wqe->ssn, qp->s_lsn + 1) > 0) goto bail; ohdr->u.rc.reth.vaddr = cpu_to_be64(wqe->wr.wr.rdma.remote_addr); ohdr->u.rc.reth.rkey = cpu_to_be32(wqe->wr.wr.rdma.rkey); ohdr->u.rc.reth.length = cpu_to_be32(len); hwords += sizeof(struct ib_reth) / sizeof(u32); wqe->lpsn = wqe->psn; if (len > pmtu) { wqe->lpsn += (len - 1) / pmtu; qp->s_state = OP(RDMA_WRITE_FIRST); len = pmtu; break; } if (wqe->wr.opcode == IB_WR_RDMA_WRITE) qp->s_state = OP(RDMA_WRITE_ONLY); else { qp->s_state = OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE); /* Immediate data comes after RETH */ ohdr->u.rc.imm_data = wqe->wr.ex.imm_data; hwords += 1; if (wqe->wr.send_flags & IB_SEND_SOLICITED) bth0 |= 1 << 23; } bth2 = 1 << 31; /* Request ACK. */ if (++qp->s_cur == qp->s_size) qp->s_cur = 0; break; case IB_WR_RDMA_READ: /* * Don't allow more operations to be started * than the QP limits allow. */ if (newreq) { if (qp->s_num_rd_atomic >= qp->s_max_rd_atomic) { qp->s_flags |= IPATH_S_RDMAR_PENDING; goto bail; } qp->s_num_rd_atomic++; if (qp->s_lsn != (u32) -1) qp->s_lsn++; /* * Adjust s_next_psn to count the * expected number of responses. */ if (len > pmtu) qp->s_next_psn += (len - 1) / pmtu; wqe->lpsn = qp->s_next_psn++; } ohdr->u.rc.reth.vaddr = cpu_to_be64(wqe->wr.wr.rdma.remote_addr); ohdr->u.rc.reth.rkey = cpu_to_be32(wqe->wr.wr.rdma.rkey); ohdr->u.rc.reth.length = cpu_to_be32(len); qp->s_state = OP(RDMA_READ_REQUEST); hwords += sizeof(ohdr->u.rc.reth) / sizeof(u32); ss = NULL; len = 0; if (++qp->s_cur == qp->s_size) qp->s_cur = 0; break; case IB_WR_ATOMIC_CMP_AND_SWP: case IB_WR_ATOMIC_FETCH_AND_ADD: /* * Don't allow more operations to be started * than the QP limits allow. */ if (newreq) { if (qp->s_num_rd_atomic >= qp->s_max_rd_atomic) { qp->s_flags |= IPATH_S_RDMAR_PENDING; goto bail; } qp->s_num_rd_atomic++; if (qp->s_lsn != (u32) -1) qp->s_lsn++; wqe->lpsn = wqe->psn; } if (wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP) { qp->s_state = OP(COMPARE_SWAP); ohdr->u.atomic_eth.swap_data = cpu_to_be64( wqe->wr.wr.atomic.swap); ohdr->u.atomic_eth.compare_data = cpu_to_be64( wqe->wr.wr.atomic.compare_add); } else { qp->s_state = OP(FETCH_ADD); ohdr->u.atomic_eth.swap_data = cpu_to_be64( wqe->wr.wr.atomic.compare_add); ohdr->u.atomic_eth.compare_data = 0; } ohdr->u.atomic_eth.vaddr[0] = cpu_to_be32( wqe->wr.wr.atomic.remote_addr >> 32); ohdr->u.atomic_eth.vaddr[1] = cpu_to_be32( wqe->wr.wr.atomic.remote_addr); ohdr->u.atomic_eth.rkey = cpu_to_be32( wqe->wr.wr.atomic.rkey); hwords += sizeof(struct ib_atomic_eth) / sizeof(u32); ss = NULL; len = 0; if (++qp->s_cur == qp->s_size) qp->s_cur = 0; break; default: goto bail; } qp->s_sge.sge = wqe->sg_list[0]; qp->s_sge.sg_list = wqe->sg_list + 1; qp->s_sge.num_sge = wqe->wr.num_sge; qp->s_len = wqe->length; if (newreq) { qp->s_tail++; if (qp->s_tail >= qp->s_size) qp->s_tail = 0; } bth2 |= qp->s_psn & IPATH_PSN_MASK; if (wqe->wr.opcode == IB_WR_RDMA_READ) qp->s_psn = wqe->lpsn + 1; else { qp->s_psn++; if (ipath_cmp24(qp->s_psn, qp->s_next_psn) > 0) qp->s_next_psn = qp->s_psn; } /* * Put the QP on the pending list so lost ACKs will cause * a retry. More than one request can be pending so the * QP may already be on the dev->pending list. */ spin_lock(&dev->pending_lock); if (list_empty(&qp->timerwait)) list_add_tail(&qp->timerwait, &dev->pending[dev->pending_index]); spin_unlock(&dev->pending_lock); break; case OP(RDMA_READ_RESPONSE_FIRST): /* * This case can only happen if a send is restarted. * See ipath_restart_rc(). */ ipath_init_restart(qp, wqe); /* FALLTHROUGH */ case OP(SEND_FIRST): qp->s_state = OP(SEND_MIDDLE); /* FALLTHROUGH */ case OP(SEND_MIDDLE): bth2 = qp->s_psn++ & IPATH_PSN_MASK; if (ipath_cmp24(qp->s_psn, qp->s_next_psn) > 0) qp->s_next_psn = qp->s_psn; ss = &qp->s_sge; len = qp->s_len; if (len > pmtu) { len = pmtu; break; } if (wqe->wr.opcode == IB_WR_SEND) qp->s_state = OP(SEND_LAST); else { qp->s_state = OP(SEND_LAST_WITH_IMMEDIATE); /* Immediate data comes after the BTH */ ohdr->u.imm_data = wqe->wr.ex.imm_data; hwords += 1; } if (wqe->wr.send_flags & IB_SEND_SOLICITED) bth0 |= 1 << 23; bth2 |= 1 << 31; /* Request ACK. */ qp->s_cur++; if (qp->s_cur >= qp->s_size) qp->s_cur = 0; break; case OP(RDMA_READ_RESPONSE_LAST): /* * This case can only happen if a RDMA write is restarted. * See ipath_restart_rc(). */ ipath_init_restart(qp, wqe); /* FALLTHROUGH */ case OP(RDMA_WRITE_FIRST): qp->s_state = OP(RDMA_WRITE_MIDDLE); /* FALLTHROUGH */ case OP(RDMA_WRITE_MIDDLE): bth2 = qp->s_psn++ & IPATH_PSN_MASK; if (ipath_cmp24(qp->s_psn, qp->s_next_psn) > 0) qp->s_next_psn = qp->s_psn; ss = &qp->s_sge; len = qp->s_len; if (len > pmtu) { len = pmtu; break; } if (wqe->wr.opcode == IB_WR_RDMA_WRITE) qp->s_state = OP(RDMA_WRITE_LAST); else { qp->s_state = OP(RDMA_WRITE_LAST_WITH_IMMEDIATE); /* Immediate data comes after the BTH */ ohdr->u.imm_data = wqe->wr.ex.imm_data; hwords += 1; if (wqe->wr.send_flags & IB_SEND_SOLICITED) bth0 |= 1 << 23; } bth2 |= 1 << 31; /* Request ACK. */ qp->s_cur++; if (qp->s_cur >= qp->s_size) qp->s_cur = 0; break; case OP(RDMA_READ_RESPONSE_MIDDLE): /* * This case can only happen if a RDMA read is restarted. * See ipath_restart_rc(). */ ipath_init_restart(qp, wqe); len = ((qp->s_psn - wqe->psn) & IPATH_PSN_MASK) * pmtu; ohdr->u.rc.reth.vaddr = cpu_to_be64(wqe->wr.wr.rdma.remote_addr + len); ohdr->u.rc.reth.rkey = cpu_to_be32(wqe->wr.wr.rdma.rkey); ohdr->u.rc.reth.length = cpu_to_be32(qp->s_len); qp->s_state = OP(RDMA_READ_REQUEST); hwords += sizeof(ohdr->u.rc.reth) / sizeof(u32); bth2 = qp->s_psn++ & IPATH_PSN_MASK; if (ipath_cmp24(qp->s_psn, qp->s_next_psn) > 0) qp->s_next_psn = qp->s_psn; ss = NULL; len = 0; qp->s_cur++; if (qp->s_cur == qp->s_size) qp->s_cur = 0; break; } if (ipath_cmp24(qp->s_psn, qp->s_last_psn + IPATH_PSN_CREDIT - 1) >= 0) bth2 |= 1 << 31; /* Request ACK. */ qp->s_len -= len; qp->s_hdrwords = hwords; qp->s_cur_sge = ss; qp->s_cur_size = len; ipath_make_ruc_header(dev, qp, ohdr, bth0 | (qp->s_state << 24), bth2); done: ret = 1; bail: spin_unlock_irqrestore(&qp->s_lock, flags); return ret; } /** * send_rc_ack - Construct an ACK packet and send it * @qp: a pointer to the QP * * This is called from ipath_rc_rcv() and only uses the receive * side QP state. * Note that RDMA reads and atomics are handled in the * send side QP state and tasklet. */ static void send_rc_ack(struct ipath_qp *qp) { struct ipath_ibdev *dev = to_idev(qp->ibqp.device); struct ipath_devdata *dd; u16 lrh0; u32 bth0; u32 hwords; u32 __iomem *piobuf; struct ipath_ib_header hdr; struct ipath_other_headers *ohdr; unsigned long flags; spin_lock_irqsave(&qp->s_lock, flags); /* Don't send ACK or NAK if a RDMA read or atomic is pending. */ if (qp->r_head_ack_queue != qp->s_tail_ack_queue || (qp->s_flags & IPATH_S_ACK_PENDING) || qp->s_ack_state != OP(ACKNOWLEDGE)) goto queue_ack; spin_unlock_irqrestore(&qp->s_lock, flags); dd = dev->dd; piobuf = ipath_getpiobuf(dd, 0, NULL); if (!piobuf) { /* * We are out of PIO buffers at the moment. * Pass responsibility for sending the ACK to the * send tasklet so that when a PIO buffer becomes * available, the ACK is sent ahead of other outgoing * packets. */ spin_lock_irqsave(&qp->s_lock, flags); goto queue_ack; } /* Construct the header. */ ohdr = &hdr.u.oth; lrh0 = IPATH_LRH_BTH; /* header size in 32-bit words LRH+BTH+AETH = (8+12+4)/4. */ hwords = 6; if (unlikely(qp->remote_ah_attr.ah_flags & IB_AH_GRH)) { hwords += ipath_make_grh(dev, &hdr.u.l.grh, &qp->remote_ah_attr.grh, hwords, 0); ohdr = &hdr.u.l.oth; lrh0 = IPATH_LRH_GRH; } /* read pkey_index w/o lock (its atomic) */ bth0 = ipath_get_pkey(dd, qp->s_pkey_index) | (OP(ACKNOWLEDGE) << 24) | (1 << 22); if (qp->r_nak_state) ohdr->u.aeth = cpu_to_be32((qp->r_msn & IPATH_MSN_MASK) | (qp->r_nak_state << IPATH_AETH_CREDIT_SHIFT)); else ohdr->u.aeth = ipath_compute_aeth(qp); lrh0 |= qp->remote_ah_attr.sl << 4; hdr.lrh[0] = cpu_to_be16(lrh0); hdr.lrh[1] = cpu_to_be16(qp->remote_ah_attr.dlid); hdr.lrh[2] = cpu_to_be16(hwords + SIZE_OF_CRC); hdr.lrh[3] = cpu_to_be16(dd->ipath_lid); ohdr->bth[0] = cpu_to_be32(bth0); ohdr->bth[1] = cpu_to_be32(qp->remote_qpn); ohdr->bth[2] = cpu_to_be32(qp->r_ack_psn & IPATH_PSN_MASK); writeq(hwords + 1, piobuf); if (dd->ipath_flags & IPATH_PIO_FLUSH_WC) { u32 *hdrp = (u32 *) &hdr; ipath_flush_wc(); __iowrite32_copy(piobuf + 2, hdrp, hwords - 1); ipath_flush_wc(); __raw_writel(hdrp[hwords - 1], piobuf + hwords + 1); } else __iowrite32_copy(piobuf + 2, (u32 *) &hdr, hwords); ipath_flush_wc(); dev->n_unicast_xmit++; goto done; queue_ack: dev->n_rc_qacks++; qp->s_flags |= IPATH_S_ACK_PENDING; qp->s_nak_state = qp->r_nak_state; qp->s_ack_psn = qp->r_ack_psn; spin_unlock_irqrestore(&qp->s_lock, flags); /* Call ipath_do_rc_send() in another thread. */ tasklet_hi_schedule(&qp->s_task); done: return; } /** * reset_psn - reset the QP state to send starting from PSN * @qp: the QP * @psn: the packet sequence number to restart at * * This is called from ipath_rc_rcv() to process an incoming RC ACK * for the given QP. * Called at interrupt level with the QP s_lock held. */ static void reset_psn(struct ipath_qp *qp, u32 psn) { u32 n = qp->s_last; struct ipath_swqe *wqe = get_swqe_ptr(qp, n); u32 opcode; qp->s_cur = n; /* * If we are starting the request from the beginning, * let the normal send code handle initialization. */ if (ipath_cmp24(psn, wqe->psn) <= 0) { qp->s_state = OP(SEND_LAST); goto done; } /* Find the work request opcode corresponding to the given PSN. */ opcode = wqe->wr.opcode; for (;;) { int diff; if (++n == qp->s_size) n = 0; if (n == qp->s_tail) break; wqe = get_swqe_ptr(qp, n); diff = ipath_cmp24(psn, wqe->psn); if (diff < 0) break; qp->s_cur = n; /* * If we are starting the request from the beginning, * let the normal send code handle initialization. */ if (diff == 0) { qp->s_state = OP(SEND_LAST); goto done; } opcode = wqe->wr.opcode; } /* * Set the state to restart in the middle of a request. * Don't change the s_sge, s_cur_sge, or s_cur_size. * See ipath_do_rc_send(). */ switch (opcode) { case IB_WR_SEND: case IB_WR_SEND_WITH_IMM: qp->s_state = OP(RDMA_READ_RESPONSE_FIRST); break; case IB_WR_RDMA_WRITE: case IB_WR_RDMA_WRITE_WITH_IMM: qp->s_state = OP(RDMA_READ_RESPONSE_LAST); break; case IB_WR_RDMA_READ: qp->s_state = OP(RDMA_READ_RESPONSE_MIDDLE); break; default: /* * This case shouldn't happen since its only * one PSN per req. */ qp->s_state = OP(SEND_LAST); } done: qp->s_psn = psn; } /** * ipath_restart_rc - back up requester to resend the last un-ACKed request * @qp: the QP to restart * @psn: packet sequence number for the request * @wc: the work completion request * * The QP s_lock should be held and interrupts disabled. */ void ipath_restart_rc(struct ipath_qp *qp, u32 psn) { struct ipath_swqe *wqe = get_swqe_ptr(qp, qp->s_last); struct ipath_ibdev *dev; if (qp->s_retry == 0) { ipath_send_complete(qp, wqe, IB_WC_RETRY_EXC_ERR); ipath_error_qp(qp, IB_WC_WR_FLUSH_ERR); goto bail; } qp->s_retry--; /* * Remove the QP from the timeout queue. * Note: it may already have been removed by ipath_ib_timer(). */ dev = to_idev(qp->ibqp.device); spin_lock(&dev->pending_lock); if (!list_empty(&qp->timerwait)) list_del_init(&qp->timerwait); if (!list_empty(&qp->piowait)) list_del_init(&qp->piowait); spin_unlock(&dev->pending_lock); if (wqe->wr.opcode == IB_WR_RDMA_READ) dev->n_rc_resends++; else dev->n_rc_resends += (qp->s_psn - psn) & IPATH_PSN_MASK; reset_psn(qp, psn); tasklet_hi_schedule(&qp->s_task); bail: return; } static inline void update_last_psn(struct ipath_qp *qp, u32 psn) { if (qp->s_last_psn != psn) { qp->s_last_psn = psn; if (qp->s_wait_credit) { qp->s_wait_credit = 0; tasklet_hi_schedule(&qp->s_task); } } } /** * do_rc_ack - process an incoming RC ACK * @qp: the QP the ACK came in on * @psn: the packet sequence number of the ACK * @opcode: the opcode of the request that resulted in the ACK * * This is called from ipath_rc_rcv_resp() to process an incoming RC ACK * for the given QP. * Called at interrupt level with the QP s_lock held and interrupts disabled. * Returns 1 if OK, 0 if current operation should be aborted (NAK). */ static int do_rc_ack(struct ipath_qp *qp, u32 aeth, u32 psn, int opcode, u64 val) { struct ipath_ibdev *dev = to_idev(qp->ibqp.device); struct ib_wc wc; enum ib_wc_status status; struct ipath_swqe *wqe; int ret = 0; u32 ack_psn; int diff; /* * Remove the QP from the timeout queue (or RNR timeout queue). * If ipath_ib_timer() has already removed it, * it's OK since we hold the QP s_lock and ipath_restart_rc() * just won't find anything to restart if we ACK everything. */ spin_lock(&dev->pending_lock); if (!list_empty(&qp->timerwait)) list_del_init(&qp->timerwait); spin_unlock(&dev->pending_lock); /* * Note that NAKs implicitly ACK outstanding SEND and RDMA write * requests and implicitly NAK RDMA read and atomic requests issued * before the NAK'ed request. The MSN won't include the NAK'ed * request but will include an ACK'ed request(s). */ ack_psn = psn; if (aeth >> 29) ack_psn--; wqe = get_swqe_ptr(qp, qp->s_last); /* * The MSN might be for a later WQE than the PSN indicates so * only complete WQEs that the PSN finishes. */ while ((diff = ipath_cmp24(ack_psn, wqe->lpsn)) >= 0) { /* * RDMA_READ_RESPONSE_ONLY is a special case since * we want to generate completion events for everything * before the RDMA read, copy the data, then generate * the completion for the read. */ if (wqe->wr.opcode == IB_WR_RDMA_READ && opcode == OP(RDMA_READ_RESPONSE_ONLY) && diff == 0) { ret = 1; goto bail; } /* * If this request is a RDMA read or atomic, and the ACK is * for a later operation, this ACK NAKs the RDMA read or * atomic. In other words, only a RDMA_READ_LAST or ONLY * can ACK a RDMA read and likewise for atomic ops. Note * that the NAK case can only happen if relaxed ordering is * used and requests are sent after an RDMA read or atomic * is sent but before the response is received. */ if ((wqe->wr.opcode == IB_WR_RDMA_READ && (opcode != OP(RDMA_READ_RESPONSE_LAST) || diff != 0)) || ((wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP || wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) && (opcode != OP(ATOMIC_ACKNOWLEDGE) || diff != 0))) { /* * The last valid PSN seen is the previous * request's. */ update_last_psn(qp, wqe->psn - 1); /* Retry this request. */ ipath_restart_rc(qp, wqe->psn); /* * No need to process the ACK/NAK since we are * restarting an earlier request. */ goto bail; } if (wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP || wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) *(u64 *) wqe->sg_list[0].vaddr = val; if (qp->s_num_rd_atomic && (wqe->wr.opcode == IB_WR_RDMA_READ || wqe->wr.opcode == IB_WR_ATOMIC_CMP_AND_SWP || wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD)) { qp->s_num_rd_atomic--; /* Restart sending task if fence is complete */ if ((qp->s_flags & IPATH_S_FENCE_PENDING) && !qp->s_num_rd_atomic) { qp->s_flags &= ~IPATH_S_FENCE_PENDING; tasklet_hi_schedule(&qp->s_task); } else if (qp->s_flags & IPATH_S_RDMAR_PENDING) { qp->s_flags &= ~IPATH_S_RDMAR_PENDING; tasklet_hi_schedule(&qp->s_task); } } /* Post a send completion queue entry if requested. */ if (!(qp->s_flags & IPATH_S_SIGNAL_REQ_WR) || (wqe->wr.send_flags & IB_SEND_SIGNALED)) { memset(&wc, 0, sizeof wc); wc.wr_id = wqe->wr.wr_id; wc.status = IB_WC_SUCCESS; wc.opcode = ib_ipath_wc_opcode[wqe->wr.opcode]; wc.byte_len = wqe->length; wc.qp = &qp->ibqp; wc.src_qp = qp->remote_qpn; wc.slid = qp->remote_ah_attr.dlid; wc.sl = qp->remote_ah_attr.sl; ipath_cq_enter(to_icq(qp->ibqp.send_cq), &wc, 0); } qp->s_retry = qp->s_retry_cnt; /* * If we are completing a request which is in the process of * being resent, we can stop resending it since we know the * responder has already seen it. */ if (qp->s_last == qp->s_cur) { if (++qp->s_cur >= qp->s_size) qp->s_cur = 0; qp->s_last = qp->s_cur; if (qp->s_last == qp->s_tail) break; wqe = get_swqe_ptr(qp, qp->s_cur); qp->s_state = OP(SEND_LAST); qp->s_psn = wqe->psn; } else { if (++qp->s_last >= qp->s_size) qp->s_last = 0; if (qp->s_last == qp->s_tail) break; wqe = get_swqe_ptr(qp, qp->s_last); } } switch (aeth >> 29) { case 0: /* ACK */ dev->n_rc_acks++; /* If this is a partial ACK, reset the retransmit timer. */ if (qp->s_last != qp->s_tail) { spin_lock(&dev->pending_lock); if (list_empty(&qp->timerwait)) list_add_tail(&qp->timerwait, &dev->pending[dev->pending_index]); spin_unlock(&dev->pending_lock); /* * If we get a partial ACK for a resent operation, * we can stop resending the earlier packets and * continue with the next packet the receiver wants. */ if (ipath_cmp24(qp->s_psn, psn) <= 0) { reset_psn(qp, psn + 1); tasklet_hi_schedule(&qp->s_task); } } else if (ipath_cmp24(qp->s_psn, psn) <= 0) { qp->s_state = OP(SEND_LAST); qp->s_psn = psn + 1; } ipath_get_credit(qp, aeth); qp->s_rnr_retry = qp->s_rnr_retry_cnt; qp->s_retry = qp->s_retry_cnt; update_last_psn(qp, psn); ret = 1; goto bail; case 1: /* RNR NAK */ dev->n_rnr_naks++; if (qp->s_last == qp->s_tail) goto bail; if (qp->s_rnr_retry == 0) { status = IB_WC_RNR_RETRY_EXC_ERR; goto class_b; } if (qp->s_rnr_retry_cnt < 7) qp->s_rnr_retry--; /* The last valid PSN is the previous PSN. */ update_last_psn(qp, psn - 1); if (wqe->wr.opcode == IB_WR_RDMA_READ) dev->n_rc_resends++; else dev->n_rc_resends += (qp->s_psn - psn) & IPATH_PSN_MASK; reset_psn(qp, psn); qp->s_rnr_timeout = ib_ipath_rnr_table[(aeth >> IPATH_AETH_CREDIT_SHIFT) & IPATH_AETH_CREDIT_MASK]; ipath_insert_rnr_queue(qp); goto bail; case 3: /* NAK */ if (qp->s_last == qp->s_tail) goto bail; /* The last valid PSN is the previous PSN. */ update_last_psn(qp, psn - 1); switch ((aeth >> IPATH_AETH_CREDIT_SHIFT) & IPATH_AETH_CREDIT_MASK) { case 0: /* PSN sequence error */ dev->n_seq_naks++; /* * Back up to the responder's expected PSN. * Note that we might get a NAK in the middle of an * RDMA READ response which terminates the RDMA * READ. */ ipath_restart_rc(qp, psn); break; case 1: /* Invalid Request */ status = IB_WC_REM_INV_REQ_ERR; dev->n_other_naks++; goto class_b; case 2: /* Remote Access Error */ status = IB_WC_REM_ACCESS_ERR; dev->n_other_naks++; goto class_b; case 3: /* Remote Operation Error */ status = IB_WC_REM_OP_ERR; dev->n_other_naks++; class_b: ipath_send_complete(qp, wqe, status); ipath_error_qp(qp, IB_WC_WR_FLUSH_ERR); break; default: /* Ignore other reserved NAK error codes */ goto reserved; } qp->s_rnr_retry = qp->s_rnr_retry_cnt; goto bail; default: /* 2: reserved */ reserved: /* Ignore reserved NAK codes. */ goto bail; } bail: return ret; } /** * ipath_rc_rcv_resp - process an incoming RC response packet * @dev: the device this packet came in on * @ohdr: the other headers for this packet * @data: the packet data * @tlen: the packet length * @qp: the QP for this packet * @opcode: the opcode for this packet * @psn: the packet sequence number for this packet * @hdrsize: the header length * @pmtu: the path MTU * @header_in_data: true if part of the header data is in the data buffer * * This is called from ipath_rc_rcv() to process an incoming RC response * packet for the given QP. * Called at interrupt level. */ static inline void ipath_rc_rcv_resp(struct ipath_ibdev *dev, struct ipath_other_headers *ohdr, void *data, u32 tlen, struct ipath_qp *qp, u32 opcode, u32 psn, u32 hdrsize, u32 pmtu, int header_in_data) { struct ipath_swqe *wqe; enum ib_wc_status status; unsigned long flags; int diff; u32 pad; u32 aeth; u64 val; spin_lock_irqsave(&qp->s_lock, flags); /* Ignore invalid responses. */ if (ipath_cmp24(psn, qp->s_next_psn) >= 0) goto ack_done; /* Ignore duplicate responses. */ diff = ipath_cmp24(psn, qp->s_last_psn); if (unlikely(diff <= 0)) { /* Update credits for "ghost" ACKs */ if (diff == 0 && opcode == OP(ACKNOWLEDGE)) { if (!header_in_data) aeth = be32_to_cpu(ohdr->u.aeth); else { aeth = be32_to_cpu(((__be32 *) data)[0]); data += sizeof(__be32); } if ((aeth >> 29) == 0) ipath_get_credit(qp, aeth); } goto ack_done; } if (unlikely(qp->s_last == qp->s_tail)) goto ack_done; wqe = get_swqe_ptr(qp, qp->s_last); status = IB_WC_SUCCESS; switch (opcode) { case OP(ACKNOWLEDGE): case OP(ATOMIC_ACKNOWLEDGE): case OP(RDMA_READ_RESPONSE_FIRST): if (!header_in_data) aeth = be32_to_cpu(ohdr->u.aeth); else { aeth = be32_to_cpu(((__be32 *) data)[0]); data += sizeof(__be32); } if (opcode == OP(ATOMIC_ACKNOWLEDGE)) { if (!header_in_data) { __be32 *p = ohdr->u.at.atomic_ack_eth; val = ((u64) be32_to_cpu(p[0]) << 32) | be32_to_cpu(p[1]); } else val = be64_to_cpu(((__be64 *) data)[0]); } else val = 0; if (!do_rc_ack(qp, aeth, psn, opcode, val) || opcode != OP(RDMA_READ_RESPONSE_FIRST)) goto ack_done; hdrsize += 4; wqe = get_swqe_ptr(qp, qp->s_last); if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ)) goto ack_op_err; /* * If this is a response to a resent RDMA read, we * have to be careful to copy the data to the right * location. */ qp->s_rdma_read_len = restart_sge(&qp->s_rdma_read_sge, wqe, psn, pmtu); goto read_middle; case OP(RDMA_READ_RESPONSE_MIDDLE): /* no AETH, no ACK */ if (unlikely(ipath_cmp24(psn, qp->s_last_psn + 1))) { dev->n_rdma_seq++; ipath_restart_rc(qp, qp->s_last_psn + 1); goto ack_done; } if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ)) goto ack_op_err; read_middle: if (unlikely(tlen != (hdrsize + pmtu + 4))) goto ack_len_err; if (unlikely(pmtu >= qp->s_rdma_read_len)) goto ack_len_err; /* We got a response so update the timeout. */ spin_lock(&dev->pending_lock); if (qp->s_rnr_timeout == 0 && !list_empty(&qp->timerwait)) list_move_tail(&qp->timerwait, &dev->pending[dev->pending_index]); spin_unlock(&dev->pending_lock); if (opcode == OP(RDMA_READ_RESPONSE_MIDDLE)) qp->s_retry = qp->s_retry_cnt; /* * Update the RDMA receive state but do the copy w/o * holding the locks and blocking interrupts. */ qp->s_rdma_read_len -= pmtu; update_last_psn(qp, psn); spin_unlock_irqrestore(&qp->s_lock, flags); ipath_copy_sge(&qp->s_rdma_read_sge, data, pmtu); goto bail; case OP(RDMA_READ_RESPONSE_ONLY): if (!header_in_data) aeth = be32_to_cpu(ohdr->u.aeth); else aeth = be32_to_cpu(((__be32 *) data)[0]); if (!do_rc_ack(qp, aeth, psn, opcode, 0)) goto ack_done; /* Get the number of bytes the message was padded by. */ pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3; /* * Check that the data size is >= 0 && <= pmtu. * Remember to account for the AETH header (4) and * ICRC (4). */ if (unlikely(tlen < (hdrsize + pad + 8))) goto ack_len_err; /* * If this is a response to a resent RDMA read, we * have to be careful to copy the data to the right * location. */ wqe = get_swqe_ptr(qp, qp->s_last); qp->s_rdma_read_len = restart_sge(&qp->s_rdma_read_sge, wqe, psn, pmtu); goto read_last; case OP(RDMA_READ_RESPONSE_LAST): /* ACKs READ req. */ if (unlikely(ipath_cmp24(psn, qp->s_last_psn + 1))) { dev->n_rdma_seq++; ipath_restart_rc(qp, qp->s_last_psn + 1); goto ack_done; } if (unlikely(wqe->wr.opcode != IB_WR_RDMA_READ)) goto ack_op_err; /* Get the number of bytes the message was padded by. */ pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3; /* * Check that the data size is >= 1 && <= pmtu. * Remember to account for the AETH header (4) and * ICRC (4). */ if (unlikely(tlen <= (hdrsize + pad + 8))) goto ack_len_err; read_last: tlen -= hdrsize + pad + 8; if (unlikely(tlen != qp->s_rdma_read_len)) goto ack_len_err; if (!header_in_data) aeth = be32_to_cpu(ohdr->u.aeth); else { aeth = be32_to_cpu(((__be32 *) data)[0]); data += sizeof(__be32); } ipath_copy_sge(&qp->s_rdma_read_sge, data, tlen); (void) do_rc_ack(qp, aeth, psn, OP(RDMA_READ_RESPONSE_LAST), 0); goto ack_done; } ack_op_err: status = IB_WC_LOC_QP_OP_ERR; goto ack_err; ack_len_err: status = IB_WC_LOC_LEN_ERR; ack_err: ipath_send_complete(qp, wqe, status); ipath_error_qp(qp, IB_WC_WR_FLUSH_ERR); ack_done: spin_unlock_irqrestore(&qp->s_lock, flags); bail: return; } /** * ipath_rc_rcv_error - process an incoming duplicate or error RC packet * @dev: the device this packet came in on * @ohdr: the other headers for this packet * @data: the packet data * @qp: the QP for this packet * @opcode: the opcode for this packet * @psn: the packet sequence number for this packet * @diff: the difference between the PSN and the expected PSN * @header_in_data: true if part of the header data is in the data buffer * * This is called from ipath_rc_rcv() to process an unexpected * incoming RC packet for the given QP. * Called at interrupt level. * Return 1 if no more processing is needed; otherwise return 0 to * schedule a response to be sent. */ static inline int ipath_rc_rcv_error(struct ipath_ibdev *dev, struct ipath_other_headers *ohdr, void *data, struct ipath_qp *qp, u32 opcode, u32 psn, int diff, int header_in_data) { struct ipath_ack_entry *e; u8 i, prev; int old_req; unsigned long flags; if (diff > 0) { /* * Packet sequence error. * A NAK will ACK earlier sends and RDMA writes. * Don't queue the NAK if we already sent one. */ if (!qp->r_nak_state) { qp->r_nak_state = IB_NAK_PSN_ERROR; /* Use the expected PSN. */ qp->r_ack_psn = qp->r_psn; goto send_ack; } goto done; } /* * Handle a duplicate request. Don't re-execute SEND, RDMA * write or atomic op. Don't NAK errors, just silently drop * the duplicate request. Note that r_sge, r_len, and * r_rcv_len may be in use so don't modify them. * * We are supposed to ACK the earliest duplicate PSN but we * can coalesce an outstanding duplicate ACK. We have to * send the earliest so that RDMA reads can be restarted at * the requester's expected PSN. * * First, find where this duplicate PSN falls within the * ACKs previously sent. */ psn &= IPATH_PSN_MASK; e = NULL; old_req = 1; spin_lock_irqsave(&qp->s_lock, flags); for (i = qp->r_head_ack_queue; ; i = prev) { if (i == qp->s_tail_ack_queue) old_req = 0; if (i) prev = i - 1; else prev = IPATH_MAX_RDMA_ATOMIC; if (prev == qp->r_head_ack_queue) { e = NULL; break; } e = &qp->s_ack_queue[prev]; if (!e->opcode) { e = NULL; break; } if (ipath_cmp24(psn, e->psn) >= 0) { if (prev == qp->s_tail_ack_queue) old_req = 0; break; } } switch (opcode) { case OP(RDMA_READ_REQUEST): { struct ib_reth *reth; u32 offset; u32 len; /* * If we didn't find the RDMA read request in the ack queue, * or the send tasklet is already backed up to send an * earlier entry, we can ignore this request. */ if (!e || e->opcode != OP(RDMA_READ_REQUEST) || old_req) goto unlock_done; /* RETH comes after BTH */ if (!header_in_data) reth = &ohdr->u.rc.reth; else { reth = (struct ib_reth *)data; data += sizeof(*reth); } /* * Address range must be a subset of the original * request and start on pmtu boundaries. * We reuse the old ack_queue slot since the requester * should not back up and request an earlier PSN for the * same request. */ offset = ((psn - e->psn) & IPATH_PSN_MASK) * ib_mtu_enum_to_int(qp->path_mtu); len = be32_to_cpu(reth->length); if (unlikely(offset + len > e->rdma_sge.sge.sge_length)) goto unlock_done; if (len != 0) { u32 rkey = be32_to_cpu(reth->rkey); u64 vaddr = be64_to_cpu(reth->vaddr); int ok; ok = ipath_rkey_ok(qp, &e->rdma_sge, len, vaddr, rkey, IB_ACCESS_REMOTE_READ); if (unlikely(!ok)) goto unlock_done; } else { e->rdma_sge.sg_list = NULL; e->rdma_sge.num_sge = 0; e->rdma_sge.sge.mr = NULL; e->rdma_sge.sge.vaddr = NULL; e->rdma_sge.sge.length = 0; e->rdma_sge.sge.sge_length = 0; } e->psn = psn; qp->s_ack_state = OP(ACKNOWLEDGE); qp->s_tail_ack_queue = prev; break; } case OP(COMPARE_SWAP): case OP(FETCH_ADD): { /* * If we didn't find the atomic request in the ack queue * or the send tasklet is already backed up to send an * earlier entry, we can ignore this request. */ if (!e || e->opcode != (u8) opcode || old_req) goto unlock_done; qp->s_ack_state = OP(ACKNOWLEDGE); qp->s_tail_ack_queue = prev; break; } default: if (old_req) goto unlock_done; /* * Resend the most recent ACK if this request is * after all the previous RDMA reads and atomics. */ if (i == qp->r_head_ack_queue) { spin_unlock_irqrestore(&qp->s_lock, flags); qp->r_nak_state = 0; qp->r_ack_psn = qp->r_psn - 1; goto send_ack; } /* * Try to send a simple ACK to work around a Mellanox bug * which doesn't accept a RDMA read response or atomic * response as an ACK for earlier SENDs or RDMA writes. */ if (qp->r_head_ack_queue == qp->s_tail_ack_queue && !(qp->s_flags & IPATH_S_ACK_PENDING) && qp->s_ack_state == OP(ACKNOWLEDGE)) { spin_unlock_irqrestore(&qp->s_lock, flags); qp->r_nak_state = 0; qp->r_ack_psn = qp->s_ack_queue[i].psn - 1; goto send_ack; } /* * Resend the RDMA read or atomic op which * ACKs this duplicate request. */ qp->s_ack_state = OP(ACKNOWLEDGE); qp->s_tail_ack_queue = i; break; } qp->r_nak_state = 0; tasklet_hi_schedule(&qp->s_task); unlock_done: spin_unlock_irqrestore(&qp->s_lock, flags); done: return 1; send_ack: return 0; } void ipath_rc_error(struct ipath_qp *qp, enum ib_wc_status err) { unsigned long flags; int lastwqe; spin_lock_irqsave(&qp->s_lock, flags); lastwqe = ipath_error_qp(qp, err); spin_unlock_irqrestore(&qp->s_lock, flags); if (lastwqe) { struct ib_event ev; ev.device = qp->ibqp.device; ev.element.qp = &qp->ibqp; ev.event = IB_EVENT_QP_LAST_WQE_REACHED; qp->ibqp.event_handler(&ev, qp->ibqp.qp_context); } } static inline void ipath_update_ack_queue(struct ipath_qp *qp, unsigned n) { unsigned long flags; unsigned next; next = n + 1; if (next > IPATH_MAX_RDMA_ATOMIC) next = 0; spin_lock_irqsave(&qp->s_lock, flags); if (n == qp->s_tail_ack_queue) { qp->s_tail_ack_queue = next; qp->s_ack_state = OP(ACKNOWLEDGE); } spin_unlock_irqrestore(&qp->s_lock, flags); } /** * ipath_rc_rcv - process an incoming RC packet * @dev: the device this packet came in on * @hdr: the header of this packet * @has_grh: true if the header has a GRH * @data: the packet data * @tlen: the packet length * @qp: the QP for this packet * * This is called from ipath_qp_rcv() to process an incoming RC packet * for the given QP. * Called at interrupt level. */ void ipath_rc_rcv(struct ipath_ibdev *dev, struct ipath_ib_header *hdr, int has_grh, void *data, u32 tlen, struct ipath_qp *qp) { struct ipath_other_headers *ohdr; u32 opcode; u32 hdrsize; u32 psn; u32 pad; struct ib_wc wc; u32 pmtu = ib_mtu_enum_to_int(qp->path_mtu); int diff; struct ib_reth *reth; int header_in_data; /* Validate the SLID. See Ch. 9.6.1.5 */ if (unlikely(be16_to_cpu(hdr->lrh[3]) != qp->remote_ah_attr.dlid)) goto done; /* Check for GRH */ if (!has_grh) { ohdr = &hdr->u.oth; hdrsize = 8 + 12; /* LRH + BTH */ psn = be32_to_cpu(ohdr->bth[2]); header_in_data = 0; } else { ohdr = &hdr->u.l.oth; hdrsize = 8 + 40 + 12; /* LRH + GRH + BTH */ /* * The header with GRH is 60 bytes and the core driver sets * the eager header buffer size to 56 bytes so the last 4 * bytes of the BTH header (PSN) is in the data buffer. */ header_in_data = dev->dd->ipath_rcvhdrentsize == 16; if (header_in_data) { psn = be32_to_cpu(((__be32 *) data)[0]); data += sizeof(__be32); } else psn = be32_to_cpu(ohdr->bth[2]); } /* * Process responses (ACKs) before anything else. Note that the * packet sequence number will be for something in the send work * queue rather than the expected receive packet sequence number. * In other words, this QP is the requester. */ opcode = be32_to_cpu(ohdr->bth[0]) >> 24; if (opcode >= OP(RDMA_READ_RESPONSE_FIRST) && opcode <= OP(ATOMIC_ACKNOWLEDGE)) { ipath_rc_rcv_resp(dev, ohdr, data, tlen, qp, opcode, psn, hdrsize, pmtu, header_in_data); goto done; } /* Compute 24 bits worth of difference. */ diff = ipath_cmp24(psn, qp->r_psn); if (unlikely(diff)) { if (ipath_rc_rcv_error(dev, ohdr, data, qp, opcode, psn, diff, header_in_data)) goto done; goto send_ack; } /* Check for opcode sequence errors. */ switch (qp->r_state) { case OP(SEND_FIRST): case OP(SEND_MIDDLE): if (opcode == OP(SEND_MIDDLE) || opcode == OP(SEND_LAST) || opcode == OP(SEND_LAST_WITH_IMMEDIATE)) break; goto nack_inv; case OP(RDMA_WRITE_FIRST): case OP(RDMA_WRITE_MIDDLE): if (opcode == OP(RDMA_WRITE_MIDDLE) || opcode == OP(RDMA_WRITE_LAST) || opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE)) break; goto nack_inv; default: if (opcode == OP(SEND_MIDDLE) || opcode == OP(SEND_LAST) || opcode == OP(SEND_LAST_WITH_IMMEDIATE) || opcode == OP(RDMA_WRITE_MIDDLE) || opcode == OP(RDMA_WRITE_LAST) || opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE)) goto nack_inv; /* * Note that it is up to the requester to not send a new * RDMA read or atomic operation before receiving an ACK * for the previous operation. */ break; } memset(&wc, 0, sizeof wc); /* OK, process the packet. */ switch (opcode) { case OP(SEND_FIRST): if (!ipath_get_rwqe(qp, 0)) goto rnr_nak; qp->r_rcv_len = 0; /* FALLTHROUGH */ case OP(SEND_MIDDLE): case OP(RDMA_WRITE_MIDDLE): send_middle: /* Check for invalid length PMTU or posted rwqe len. */ if (unlikely(tlen != (hdrsize + pmtu + 4))) goto nack_inv; qp->r_rcv_len += pmtu; if (unlikely(qp->r_rcv_len > qp->r_len)) goto nack_inv; ipath_copy_sge(&qp->r_sge, data, pmtu); break; case OP(RDMA_WRITE_LAST_WITH_IMMEDIATE): /* consume RWQE */ if (!ipath_get_rwqe(qp, 1)) goto rnr_nak; goto send_last_imm; case OP(SEND_ONLY): case OP(SEND_ONLY_WITH_IMMEDIATE): if (!ipath_get_rwqe(qp, 0)) goto rnr_nak; qp->r_rcv_len = 0; if (opcode == OP(SEND_ONLY)) goto send_last; /* FALLTHROUGH */ case OP(SEND_LAST_WITH_IMMEDIATE): send_last_imm: if (header_in_data) { wc.imm_data = *(__be32 *) data; data += sizeof(__be32); } else { /* Immediate data comes after BTH */ wc.imm_data = ohdr->u.imm_data; } hdrsize += 4; wc.wc_flags = IB_WC_WITH_IMM; /* FALLTHROUGH */ case OP(SEND_LAST): case OP(RDMA_WRITE_LAST): send_last: /* Get the number of bytes the message was padded by. */ pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3; /* Check for invalid length. */ /* XXX LAST len should be >= 1 */ if (unlikely(tlen < (hdrsize + pad + 4))) goto nack_inv; /* Don't count the CRC. */ tlen -= (hdrsize + pad + 4); wc.byte_len = tlen + qp->r_rcv_len; if (unlikely(wc.byte_len > qp->r_len)) goto nack_inv; ipath_copy_sge(&qp->r_sge, data, tlen); qp->r_msn++; if (!qp->r_wrid_valid) break; qp->r_wrid_valid = 0; wc.wr_id = qp->r_wr_id; wc.status = IB_WC_SUCCESS; if (opcode == OP(RDMA_WRITE_LAST_WITH_IMMEDIATE) || opcode == OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE)) wc.opcode = IB_WC_RECV_RDMA_WITH_IMM; else wc.opcode = IB_WC_RECV; wc.qp = &qp->ibqp; wc.src_qp = qp->remote_qpn; wc.slid = qp->remote_ah_attr.dlid; wc.sl = qp->remote_ah_attr.sl; /* Signal completion event if the solicited bit is set. */ ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, (ohdr->bth[0] & __constant_cpu_to_be32(1 << 23)) != 0); break; case OP(RDMA_WRITE_FIRST): case OP(RDMA_WRITE_ONLY): case OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE): if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE))) goto nack_inv; /* consume RWQE */ /* RETH comes after BTH */ if (!header_in_data) reth = &ohdr->u.rc.reth; else { reth = (struct ib_reth *)data; data += sizeof(*reth); } hdrsize += sizeof(*reth); qp->r_len = be32_to_cpu(reth->length); qp->r_rcv_len = 0; if (qp->r_len != 0) { u32 rkey = be32_to_cpu(reth->rkey); u64 vaddr = be64_to_cpu(reth->vaddr); int ok; /* Check rkey & NAK */ ok = ipath_rkey_ok(qp, &qp->r_sge, qp->r_len, vaddr, rkey, IB_ACCESS_REMOTE_WRITE); if (unlikely(!ok)) goto nack_acc; } else { qp->r_sge.sg_list = NULL; qp->r_sge.sge.mr = NULL; qp->r_sge.sge.vaddr = NULL; qp->r_sge.sge.length = 0; qp->r_sge.sge.sge_length = 0; } if (opcode == OP(RDMA_WRITE_FIRST)) goto send_middle; else if (opcode == OP(RDMA_WRITE_ONLY)) goto send_last; if (!ipath_get_rwqe(qp, 1)) goto rnr_nak; goto send_last_imm; case OP(RDMA_READ_REQUEST): { struct ipath_ack_entry *e; u32 len; u8 next; if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ))) goto nack_inv; next = qp->r_head_ack_queue + 1; if (next > IPATH_MAX_RDMA_ATOMIC) next = 0; if (unlikely(next == qp->s_tail_ack_queue)) { if (!qp->s_ack_queue[next].sent) goto nack_inv; ipath_update_ack_queue(qp, next); } e = &qp->s_ack_queue[qp->r_head_ack_queue]; /* RETH comes after BTH */ if (!header_in_data) reth = &ohdr->u.rc.reth; else { reth = (struct ib_reth *)data; data += sizeof(*reth); } len = be32_to_cpu(reth->length); if (len) { u32 rkey = be32_to_cpu(reth->rkey); u64 vaddr = be64_to_cpu(reth->vaddr); int ok; /* Check rkey & NAK */ ok = ipath_rkey_ok(qp, &e->rdma_sge, len, vaddr, rkey, IB_ACCESS_REMOTE_READ); if (unlikely(!ok)) goto nack_acc; /* * Update the next expected PSN. We add 1 later * below, so only add the remainder here. */ if (len > pmtu) qp->r_psn += (len - 1) / pmtu; } else { e->rdma_sge.sg_list = NULL; e->rdma_sge.num_sge = 0; e->rdma_sge.sge.mr = NULL; e->rdma_sge.sge.vaddr = NULL; e->rdma_sge.sge.length = 0; e->rdma_sge.sge.sge_length = 0; } e->opcode = opcode; e->sent = 0; e->psn = psn; /* * We need to increment the MSN here instead of when we * finish sending the result since a duplicate request would * increment it more than once. */ qp->r_msn++; qp->r_psn++; qp->r_state = opcode; qp->r_nak_state = 0; barrier(); qp->r_head_ack_queue = next; /* Call ipath_do_rc_send() in another thread. */ tasklet_hi_schedule(&qp->s_task); goto done; } case OP(COMPARE_SWAP): case OP(FETCH_ADD): { struct ib_atomic_eth *ateth; struct ipath_ack_entry *e; u64 vaddr; atomic64_t *maddr; u64 sdata; u32 rkey; u8 next; if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC))) goto nack_inv; next = qp->r_head_ack_queue + 1; if (next > IPATH_MAX_RDMA_ATOMIC) next = 0; if (unlikely(next == qp->s_tail_ack_queue)) { if (!qp->s_ack_queue[next].sent) goto nack_inv; ipath_update_ack_queue(qp, next); } if (!header_in_data) ateth = &ohdr->u.atomic_eth; else ateth = (struct ib_atomic_eth *)data; vaddr = ((u64) be32_to_cpu(ateth->vaddr[0]) << 32) | be32_to_cpu(ateth->vaddr[1]); if (unlikely(vaddr & (sizeof(u64) - 1))) goto nack_inv; rkey = be32_to_cpu(ateth->rkey); /* Check rkey & NAK */ if (unlikely(!ipath_rkey_ok(qp, &qp->r_sge, sizeof(u64), vaddr, rkey, IB_ACCESS_REMOTE_ATOMIC))) goto nack_acc; /* Perform atomic OP and save result. */ maddr = (atomic64_t *) qp->r_sge.sge.vaddr; sdata = be64_to_cpu(ateth->swap_data); e = &qp->s_ack_queue[qp->r_head_ack_queue]; e->atomic_data = (opcode == OP(FETCH_ADD)) ? (u64) atomic64_add_return(sdata, maddr) - sdata : (u64) cmpxchg((u64 *) qp->r_sge.sge.vaddr, be64_to_cpu(ateth->compare_data), sdata); e->opcode = opcode; e->sent = 0; e->psn = psn & IPATH_PSN_MASK; qp->r_msn++; qp->r_psn++; qp->r_state = opcode; qp->r_nak_state = 0; barrier(); qp->r_head_ack_queue = next; /* Call ipath_do_rc_send() in another thread. */ tasklet_hi_schedule(&qp->s_task); goto done; } default: /* NAK unknown opcodes. */ goto nack_inv; } qp->r_psn++; qp->r_state = opcode; qp->r_ack_psn = psn; qp->r_nak_state = 0; /* Send an ACK if requested or required. */ if (psn & (1 << 31)) goto send_ack; goto done; rnr_nak: qp->r_nak_state = IB_RNR_NAK | qp->r_min_rnr_timer; qp->r_ack_psn = qp->r_psn; goto send_ack; nack_inv: ipath_rc_error(qp, IB_WC_LOC_QP_OP_ERR); qp->r_nak_state = IB_NAK_INVALID_REQUEST; qp->r_ack_psn = qp->r_psn; goto send_ack; nack_acc: ipath_rc_error(qp, IB_WC_LOC_PROT_ERR); qp->r_nak_state = IB_NAK_REMOTE_ACCESS_ERROR; qp->r_ack_psn = qp->r_psn; send_ack: send_rc_ack(qp); done: return; }