new file mode 100644
@@ -0,0 +1,944 @@
+/*
+ *
+ * This file is provided under a dual BSD/GPLv2 license. When using or
+ * redistributing this file, you may do so under either license.
+ *
+ * GPL LICENSE SUMMARY
+ *
+ * Copyright(c) 2015 Intel Corporation.
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of version 2 of the GNU General Public License as
+ * published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * BSD LICENSE
+ *
+ * Copyright(c) 2015 Intel Corporation.
+ *
+ * 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.
+ * - Neither the name of Intel Corporation nor the names of its
+ * contributors may be used to endorse or promote products derived
+ * from this software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+ * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+ * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+ * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+ * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+ * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+ * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+ * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+ * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+ *
+ */
+
+#include <linux/spinlock.h>
+
+#include "hfi.h"
+#include "mad.h"
+#include "qp.h"
+#include "sdma.h"
+
+/*
+ * Convert the AETH RNR timeout code into the number of microseconds.
+ */
+const u32 ib_hfi1_rnr_table[32] = {
+ 655360, /* 00: 655.36 */
+ 10, /* 01: .01 */
+ 20, /* 02 .02 */
+ 30, /* 03: .03 */
+ 40, /* 04: .04 */
+ 60, /* 05: .06 */
+ 80, /* 06: .08 */
+ 120, /* 07: .12 */
+ 160, /* 08: .16 */
+ 240, /* 09: .24 */
+ 320, /* 0A: .32 */
+ 480, /* 0B: .48 */
+ 640, /* 0C: .64 */
+ 960, /* 0D: .96 */
+ 1280, /* 0E: 1.28 */
+ 1920, /* 0F: 1.92 */
+ 2560, /* 10: 2.56 */
+ 3840, /* 11: 3.84 */
+ 5120, /* 12: 5.12 */
+ 7680, /* 13: 7.68 */
+ 10240, /* 14: 10.24 */
+ 15360, /* 15: 15.36 */
+ 20480, /* 16: 20.48 */
+ 30720, /* 17: 30.72 */
+ 40960, /* 18: 40.96 */
+ 61440, /* 19: 61.44 */
+ 81920, /* 1A: 81.92 */
+ 122880, /* 1B: 122.88 */
+ 163840, /* 1C: 163.84 */
+ 245760, /* 1D: 245.76 */
+ 327680, /* 1E: 327.68 */
+ 491520 /* 1F: 491.52 */
+};
+
+/*
+ * Validate a RWQE and fill in the SGE state.
+ * Return 1 if OK.
+ */
+static int init_sge(struct hfi1_qp *qp, struct hfi1_rwqe *wqe)
+{
+ int i, j, ret;
+ struct ib_wc wc;
+ struct hfi1_lkey_table *rkt;
+ struct hfi1_pd *pd;
+ struct hfi1_sge_state *ss;
+
+ rkt = &to_idev(qp->ibqp.device)->lk_table;
+ pd = to_ipd(qp->ibqp.srq ? qp->ibqp.srq->pd : qp->ibqp.pd);
+ ss = &qp->r_sge;
+ ss->sg_list = qp->r_sg_list;
+ qp->r_len = 0;
+ for (i = j = 0; i < wqe->num_sge; i++) {
+ if (wqe->sg_list[i].length == 0)
+ continue;
+ /* Check LKEY */
+ if (!hfi1_lkey_ok(rkt, pd, j ? &ss->sg_list[j - 1] : &ss->sge,
+ &wqe->sg_list[i], IB_ACCESS_LOCAL_WRITE))
+ goto bad_lkey;
+ qp->r_len += wqe->sg_list[i].length;
+ j++;
+ }
+ ss->num_sge = j;
+ ss->total_len = qp->r_len;
+ ret = 1;
+ goto bail;
+
+bad_lkey:
+ while (j) {
+ struct hfi1_sge *sge = --j ? &ss->sg_list[j - 1] : &ss->sge;
+
+ hfi1_put_mr(sge->mr);
+ }
+ ss->num_sge = 0;
+ memset(&wc, 0, sizeof(wc));
+ wc.wr_id = wqe->wr_id;
+ wc.status = IB_WC_LOC_PROT_ERR;
+ wc.opcode = IB_WC_RECV;
+ wc.qp = &qp->ibqp;
+ /* Signal solicited completion event. */
+ hfi1_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
+ ret = 0;
+bail:
+ return ret;
+}
+
+/**
+ * hfi1_get_rwqe - copy the next RWQE into the QP's RWQE
+ * @qp: the QP
+ * @wr_id_only: update qp->r_wr_id only, not qp->r_sge
+ *
+ * Return -1 if there is a local error, 0 if no RWQE is available,
+ * otherwise return 1.
+ *
+ * Can be called from interrupt level.
+ */
+int hfi1_get_rwqe(struct hfi1_qp *qp, int wr_id_only)
+{
+ unsigned long flags;
+ struct hfi1_rq *rq;
+ struct hfi1_rwq *wq;
+ struct hfi1_srq *srq;
+ struct hfi1_rwqe *wqe;
+ void (*handler)(struct ib_event *, void *);
+ u32 tail;
+ int ret;
+
+ if (qp->ibqp.srq) {
+ srq = to_isrq(qp->ibqp.srq);
+ handler = srq->ibsrq.event_handler;
+ rq = &srq->rq;
+ } else {
+ srq = NULL;
+ handler = NULL;
+ rq = &qp->r_rq;
+ }
+
+ spin_lock_irqsave(&rq->lock, flags);
+ if (!(ib_hfi1_state_ops[qp->state] & HFI1_PROCESS_RECV_OK)) {
+ ret = 0;
+ goto unlock;
+ }
+
+ wq = rq->wq;
+ tail = wq->tail;
+ /* Validate tail before using it since it is user writable. */
+ if (tail >= rq->size)
+ tail = 0;
+ if (unlikely(tail == wq->head)) {
+ ret = 0;
+ goto unlock;
+ }
+ /* Make sure entry is read after head index is read. */
+ smp_rmb();
+ wqe = get_rwqe_ptr(rq, tail);
+ /*
+ * Even though we update the tail index in memory, the verbs
+ * consumer is not supposed to post more entries until a
+ * completion is generated.
+ */
+ if (++tail >= rq->size)
+ tail = 0;
+ wq->tail = tail;
+ if (!wr_id_only && !init_sge(qp, wqe)) {
+ ret = -1;
+ goto unlock;
+ }
+ qp->r_wr_id = wqe->wr_id;
+
+ ret = 1;
+ set_bit(HFI1_R_WRID_VALID, &qp->r_aflags);
+ if (handler) {
+ u32 n;
+
+ /*
+ * Validate head pointer value and compute
+ * the number of remaining WQEs.
+ */
+ n = wq->head;
+ if (n >= rq->size)
+ n = 0;
+ if (n < tail)
+ n += rq->size - tail;
+ else
+ n -= tail;
+ if (n < srq->limit) {
+ struct ib_event ev;
+
+ srq->limit = 0;
+ spin_unlock_irqrestore(&rq->lock, flags);
+ ev.device = qp->ibqp.device;
+ ev.element.srq = qp->ibqp.srq;
+ ev.event = IB_EVENT_SRQ_LIMIT_REACHED;
+ handler(&ev, srq->ibsrq.srq_context);
+ goto bail;
+ }
+ }
+unlock:
+ spin_unlock_irqrestore(&rq->lock, flags);
+bail:
+ return ret;
+}
+
+/*
+ * Switch to alternate path.
+ * The QP s_lock should be held and interrupts disabled.
+ */
+void hfi1_migrate_qp(struct hfi1_qp *qp)
+{
+ struct ib_event ev;
+
+ qp->s_mig_state = IB_MIG_MIGRATED;
+ qp->remote_ah_attr = qp->alt_ah_attr;
+ qp->port_num = qp->alt_ah_attr.port_num;
+ qp->s_pkey_index = qp->s_alt_pkey_index;
+ qp->s_flags |= HFI1_S_AHG_CLEAR;
+
+ ev.device = qp->ibqp.device;
+ ev.element.qp = &qp->ibqp;
+ ev.event = IB_EVENT_PATH_MIG;
+ qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
+}
+
+static __be64 get_sguid(struct hfi1_ibport *ibp, unsigned index)
+{
+ if (!index) {
+ struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
+
+ return ppd->guid;
+ }
+ return ibp->guids[index - 1];
+}
+
+static int gid_ok(union ib_gid *gid, __be64 gid_prefix, __be64 id)
+{
+ return (gid->global.interface_id == id &&
+ (gid->global.subnet_prefix == gid_prefix ||
+ gid->global.subnet_prefix == IB_DEFAULT_GID_PREFIX));
+}
+
+/*
+ *
+ * This should be called with the QP r_lock held.
+ *
+ * The s_lock will be acquired around the hfi1_migrate_qp() call.
+ */
+int hfi1_ruc_check_hdr(struct hfi1_ibport *ibp, struct hfi1_ib_header *hdr,
+ int has_grh, struct hfi1_qp *qp, u32 bth0)
+{
+ __be64 guid;
+ unsigned long flags;
+ u8 sc5 = ibp->sl_to_sc[qp->remote_ah_attr.sl];
+
+ if (qp->s_mig_state == IB_MIG_ARMED && (bth0 & IB_BTH_MIG_REQ)) {
+ if (!has_grh) {
+ if (qp->alt_ah_attr.ah_flags & IB_AH_GRH)
+ goto err;
+ } else {
+ if (!(qp->alt_ah_attr.ah_flags & IB_AH_GRH))
+ goto err;
+ guid = get_sguid(ibp, qp->alt_ah_attr.grh.sgid_index);
+ if (!gid_ok(&hdr->u.l.grh.dgid, ibp->gid_prefix, guid))
+ goto err;
+ if (!gid_ok(&hdr->u.l.grh.sgid,
+ qp->alt_ah_attr.grh.dgid.global.subnet_prefix,
+ qp->alt_ah_attr.grh.dgid.global.interface_id))
+ goto err;
+ }
+ if (unlikely(ingress_pkey_check(ppd_from_ibp(ibp), (u16)bth0,
+ sc5, qp->s_alt_pkey_index,
+ be16_to_cpu(hdr->lrh[3])))) {
+ hfi1_bad_pqkey(ibp, IB_NOTICE_TRAP_BAD_PKEY,
+ (u16)bth0,
+ (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF,
+ 0, qp->ibqp.qp_num,
+ hdr->lrh[3], hdr->lrh[1]);
+ goto err;
+ }
+ /* Validate the SLID. See Ch. 9.6.1.5 and 17.2.8 */
+ if (be16_to_cpu(hdr->lrh[3]) != qp->alt_ah_attr.dlid ||
+ ppd_from_ibp(ibp)->port != qp->alt_ah_attr.port_num)
+ goto err;
+ spin_lock_irqsave(&qp->s_lock, flags);
+ hfi1_migrate_qp(qp);
+ spin_unlock_irqrestore(&qp->s_lock, flags);
+ } else {
+ if (!has_grh) {
+ if (qp->remote_ah_attr.ah_flags & IB_AH_GRH)
+ goto err;
+ } else {
+ if (!(qp->remote_ah_attr.ah_flags & IB_AH_GRH))
+ goto err;
+ guid = get_sguid(ibp,
+ qp->remote_ah_attr.grh.sgid_index);
+ if (!gid_ok(&hdr->u.l.grh.dgid, ibp->gid_prefix, guid))
+ goto err;
+ if (!gid_ok(&hdr->u.l.grh.sgid,
+ qp->remote_ah_attr.grh.dgid.global.subnet_prefix,
+ qp->remote_ah_attr.grh.dgid.global.interface_id))
+ goto err;
+ }
+ if (unlikely(ingress_pkey_check(ppd_from_ibp(ibp), (u16)bth0,
+ sc5, qp->s_pkey_index,
+ be16_to_cpu(hdr->lrh[3])))) {
+ hfi1_bad_pqkey(ibp, IB_NOTICE_TRAP_BAD_PKEY,
+ (u16)bth0,
+ (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF,
+ 0, qp->ibqp.qp_num,
+ hdr->lrh[3], hdr->lrh[1]);
+ goto err;
+ }
+ /* Validate the SLID. See Ch. 9.6.1.5 */
+ if (be16_to_cpu(hdr->lrh[3]) != qp->remote_ah_attr.dlid ||
+ ppd_from_ibp(ibp)->port != qp->port_num)
+ goto err;
+ if (qp->s_mig_state == IB_MIG_REARM &&
+ !(bth0 & IB_BTH_MIG_REQ))
+ qp->s_mig_state = IB_MIG_ARMED;
+ }
+
+ return 0;
+
+err:
+ return 1;
+}
+
+/**
+ * ruc_loopback - handle UC and RC loopback requests
+ * @sqp: the sending QP
+ *
+ * This is called from hfi1_do_send() to
+ * forward a WQE addressed to the same HCA.
+ * Note that although we are single threaded due to the tasklet, we still
+ * have to protect against post_send(). We don't have to worry about
+ * receive interrupts since this is a connected protocol and all packets
+ * will pass through here.
+ */
+static void ruc_loopback(struct hfi1_qp *sqp)
+{
+ struct hfi1_ibport *ibp = to_iport(sqp->ibqp.device, sqp->port_num);
+ struct hfi1_qp *qp;
+ struct hfi1_swqe *wqe;
+ struct hfi1_sge *sge;
+ unsigned long flags;
+ struct ib_wc wc;
+ u64 sdata;
+ atomic64_t *maddr;
+ enum ib_wc_status send_status;
+ int release;
+ int ret;
+
+ /*
+ * Note that we check the responder QP state after
+ * checking the requester's state.
+ */
+ qp = hfi1_lookup_qpn(ibp, sqp->remote_qpn);
+
+ spin_lock_irqsave(&sqp->s_lock, flags);
+
+ /* Return if we are already busy processing a work request. */
+ if ((sqp->s_flags & (HFI1_S_BUSY | HFI1_S_ANY_WAIT)) ||
+ !(ib_hfi1_state_ops[sqp->state] & HFI1_PROCESS_OR_FLUSH_SEND))
+ goto unlock;
+
+ sqp->s_flags |= HFI1_S_BUSY;
+
+again:
+ if (sqp->s_last == sqp->s_head)
+ goto clr_busy;
+ wqe = get_swqe_ptr(sqp, sqp->s_last);
+
+ /* Return if it is not OK to start a new work request. */
+ if (!(ib_hfi1_state_ops[sqp->state] & HFI1_PROCESS_NEXT_SEND_OK)) {
+ if (!(ib_hfi1_state_ops[sqp->state] & HFI1_FLUSH_SEND))
+ goto clr_busy;
+ /* We are in the error state, flush the work request. */
+ send_status = IB_WC_WR_FLUSH_ERR;
+ goto flush_send;
+ }
+
+ /*
+ * We can rely on the entry not changing without the s_lock
+ * being held until we update s_last.
+ * We increment s_cur to indicate s_last is in progress.
+ */
+ if (sqp->s_last == sqp->s_cur) {
+ if (++sqp->s_cur >= sqp->s_size)
+ sqp->s_cur = 0;
+ }
+ spin_unlock_irqrestore(&sqp->s_lock, flags);
+
+ if (!qp || !(ib_hfi1_state_ops[qp->state] & HFI1_PROCESS_RECV_OK) ||
+ qp->ibqp.qp_type != sqp->ibqp.qp_type) {
+ ibp->n_pkt_drops++;
+ /*
+ * For RC, the requester would timeout and retry so
+ * shortcut the timeouts and just signal too many retries.
+ */
+ if (sqp->ibqp.qp_type == IB_QPT_RC)
+ send_status = IB_WC_RETRY_EXC_ERR;
+ else
+ send_status = IB_WC_SUCCESS;
+ goto serr;
+ }
+
+ memset(&wc, 0, sizeof(wc));
+ send_status = IB_WC_SUCCESS;
+
+ release = 1;
+ sqp->s_sge.sge = wqe->sg_list[0];
+ sqp->s_sge.sg_list = wqe->sg_list + 1;
+ sqp->s_sge.num_sge = wqe->wr.num_sge;
+ sqp->s_len = wqe->length;
+ switch (wqe->wr.opcode) {
+ case IB_WR_SEND_WITH_IMM:
+ wc.wc_flags = IB_WC_WITH_IMM;
+ wc.ex.imm_data = wqe->wr.ex.imm_data;
+ /* FALLTHROUGH */
+ case IB_WR_SEND:
+ ret = hfi1_get_rwqe(qp, 0);
+ if (ret < 0)
+ goto op_err;
+ if (!ret)
+ goto rnr_nak;
+ break;
+
+ case IB_WR_RDMA_WRITE_WITH_IMM:
+ if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
+ goto inv_err;
+ wc.wc_flags = IB_WC_WITH_IMM;
+ wc.ex.imm_data = wqe->wr.ex.imm_data;
+ ret = hfi1_get_rwqe(qp, 1);
+ if (ret < 0)
+ goto op_err;
+ if (!ret)
+ goto rnr_nak;
+ /* FALLTHROUGH */
+ case IB_WR_RDMA_WRITE:
+ if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_WRITE)))
+ goto inv_err;
+ if (wqe->length == 0)
+ break;
+ if (unlikely(!hfi1_rkey_ok(qp, &qp->r_sge.sge, wqe->length,
+ wqe->wr.wr.rdma.remote_addr,
+ wqe->wr.wr.rdma.rkey,
+ IB_ACCESS_REMOTE_WRITE)))
+ goto acc_err;
+ qp->r_sge.sg_list = NULL;
+ qp->r_sge.num_sge = 1;
+ qp->r_sge.total_len = wqe->length;
+ break;
+
+ case IB_WR_RDMA_READ:
+ if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_READ)))
+ goto inv_err;
+ if (unlikely(!hfi1_rkey_ok(qp, &sqp->s_sge.sge, wqe->length,
+ wqe->wr.wr.rdma.remote_addr,
+ wqe->wr.wr.rdma.rkey,
+ IB_ACCESS_REMOTE_READ)))
+ goto acc_err;
+ release = 0;
+ sqp->s_sge.sg_list = NULL;
+ sqp->s_sge.num_sge = 1;
+ qp->r_sge.sge = wqe->sg_list[0];
+ qp->r_sge.sg_list = wqe->sg_list + 1;
+ qp->r_sge.num_sge = wqe->wr.num_sge;
+ qp->r_sge.total_len = wqe->length;
+ break;
+
+ case IB_WR_ATOMIC_CMP_AND_SWP:
+ case IB_WR_ATOMIC_FETCH_AND_ADD:
+ if (unlikely(!(qp->qp_access_flags & IB_ACCESS_REMOTE_ATOMIC)))
+ goto inv_err;
+ if (unlikely(!hfi1_rkey_ok(qp, &qp->r_sge.sge, sizeof(u64),
+ wqe->wr.wr.atomic.remote_addr,
+ wqe->wr.wr.atomic.rkey,
+ IB_ACCESS_REMOTE_ATOMIC)))
+ goto acc_err;
+ /* Perform atomic OP and save result. */
+ maddr = (atomic64_t *) qp->r_sge.sge.vaddr;
+ sdata = wqe->wr.wr.atomic.compare_add;
+ *(u64 *) sqp->s_sge.sge.vaddr =
+ (wqe->wr.opcode == IB_WR_ATOMIC_FETCH_AND_ADD) ?
+ (u64) atomic64_add_return(sdata, maddr) - sdata :
+ (u64) cmpxchg((u64 *) qp->r_sge.sge.vaddr,
+ sdata, wqe->wr.wr.atomic.swap);
+ hfi1_put_mr(qp->r_sge.sge.mr);
+ qp->r_sge.num_sge = 0;
+ goto send_comp;
+
+ default:
+ send_status = IB_WC_LOC_QP_OP_ERR;
+ goto serr;
+ }
+
+ sge = &sqp->s_sge.sge;
+ while (sqp->s_len) {
+ u32 len = sqp->s_len;
+
+ if (len > sge->length)
+ len = sge->length;
+ if (len > sge->sge_length)
+ len = sge->sge_length;
+ BUG_ON(len == 0);
+ hfi1_copy_sge(&qp->r_sge, sge->vaddr, len, release);
+ sge->vaddr += len;
+ sge->length -= len;
+ sge->sge_length -= len;
+ if (sge->sge_length == 0) {
+ if (!release)
+ hfi1_put_mr(sge->mr);
+ if (--sqp->s_sge.num_sge)
+ *sge = *sqp->s_sge.sg_list++;
+ } else if (sge->length == 0 && sge->mr->lkey) {
+ if (++sge->n >= HFI1_SEGSZ) {
+ if (++sge->m >= sge->mr->mapsz)
+ break;
+ sge->n = 0;
+ }
+ sge->vaddr =
+ sge->mr->map[sge->m]->segs[sge->n].vaddr;
+ sge->length =
+ sge->mr->map[sge->m]->segs[sge->n].length;
+ }
+ sqp->s_len -= len;
+ }
+ if (release)
+ hfi1_put_ss(&qp->r_sge);
+
+ if (!test_and_clear_bit(HFI1_R_WRID_VALID, &qp->r_aflags))
+ goto send_comp;
+
+ if (wqe->wr.opcode == IB_WR_RDMA_WRITE_WITH_IMM)
+ wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
+ else
+ wc.opcode = IB_WC_RECV;
+ wc.wr_id = qp->r_wr_id;
+ wc.status = IB_WC_SUCCESS;
+ 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;
+ wc.port_num = 1;
+ /* Signal completion event if the solicited bit is set. */
+ hfi1_cq_enter(to_icq(qp->ibqp.recv_cq), &wc,
+ wqe->wr.send_flags & IB_SEND_SOLICITED);
+
+send_comp:
+ spin_lock_irqsave(&sqp->s_lock, flags);
+ ibp->n_loop_pkts++;
+flush_send:
+ sqp->s_rnr_retry = sqp->s_rnr_retry_cnt;
+ hfi1_send_complete(sqp, wqe, send_status);
+ goto again;
+
+rnr_nak:
+ /* Handle RNR NAK */
+ if (qp->ibqp.qp_type == IB_QPT_UC)
+ goto send_comp;
+ ibp->n_rnr_naks++;
+ /*
+ * Note: we don't need the s_lock held since the BUSY flag
+ * makes this single threaded.
+ */
+ if (sqp->s_rnr_retry == 0) {
+ send_status = IB_WC_RNR_RETRY_EXC_ERR;
+ goto serr;
+ }
+ if (sqp->s_rnr_retry_cnt < 7)
+ sqp->s_rnr_retry--;
+ spin_lock_irqsave(&sqp->s_lock, flags);
+ if (!(ib_hfi1_state_ops[sqp->state] & HFI1_PROCESS_RECV_OK))
+ goto clr_busy;
+ sqp->s_flags |= HFI1_S_WAIT_RNR;
+ sqp->s_timer.function = hfi1_rc_rnr_retry;
+ sqp->s_timer.expires = jiffies +
+ usecs_to_jiffies(ib_hfi1_rnr_table[qp->r_min_rnr_timer]);
+ add_timer(&sqp->s_timer);
+ goto clr_busy;
+
+op_err:
+ send_status = IB_WC_REM_OP_ERR;
+ wc.status = IB_WC_LOC_QP_OP_ERR;
+ goto err;
+
+inv_err:
+ send_status = IB_WC_REM_INV_REQ_ERR;
+ wc.status = IB_WC_LOC_QP_OP_ERR;
+ goto err;
+
+acc_err:
+ send_status = IB_WC_REM_ACCESS_ERR;
+ wc.status = IB_WC_LOC_PROT_ERR;
+err:
+ /* responder goes to error state */
+ hfi1_rc_error(qp, wc.status);
+
+serr:
+ spin_lock_irqsave(&sqp->s_lock, flags);
+ hfi1_send_complete(sqp, wqe, send_status);
+ if (sqp->ibqp.qp_type == IB_QPT_RC) {
+ int lastwqe = hfi1_error_qp(sqp, IB_WC_WR_FLUSH_ERR);
+
+ sqp->s_flags &= ~HFI1_S_BUSY;
+ spin_unlock_irqrestore(&sqp->s_lock, flags);
+ if (lastwqe) {
+ struct ib_event ev;
+
+ ev.device = sqp->ibqp.device;
+ ev.element.qp = &sqp->ibqp;
+ ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
+ sqp->ibqp.event_handler(&ev, sqp->ibqp.qp_context);
+ }
+ goto done;
+ }
+clr_busy:
+ sqp->s_flags &= ~HFI1_S_BUSY;
+unlock:
+ spin_unlock_irqrestore(&sqp->s_lock, flags);
+done:
+ if (qp && atomic_dec_and_test(&qp->refcount))
+ wake_up(&qp->wait);
+}
+
+/**
+ * hfi1_make_grh - construct a GRH header
+ * @ibp: a pointer to the IB port
+ * @hdr: a pointer to the GRH header being constructed
+ * @grh: the global route address to send to
+ * @hwords: the number of 32 bit words of header being sent
+ * @nwords: the number of 32 bit words of data being sent
+ *
+ * Return the size of the header in 32 bit words.
+ */
+u32 hfi1_make_grh(struct hfi1_ibport *ibp, struct ib_grh *hdr,
+ struct ib_global_route *grh, u32 hwords, u32 nwords)
+{
+ hdr->version_tclass_flow =
+ cpu_to_be32((IB_GRH_VERSION << IB_GRH_VERSION_SHIFT) |
+ (grh->traffic_class << IB_GRH_TCLASS_SHIFT) |
+ (grh->flow_label << IB_GRH_FLOW_SHIFT));
+ hdr->paylen = cpu_to_be16((hwords - 2 + nwords + SIZE_OF_CRC) << 2);
+ /* next_hdr is defined by C8-7 in ch. 8.4.1 */
+ hdr->next_hdr = IB_GRH_NEXT_HDR;
+ hdr->hop_limit = grh->hop_limit;
+ /* The SGID is 32-bit aligned. */
+ hdr->sgid.global.subnet_prefix = ibp->gid_prefix;
+ hdr->sgid.global.interface_id =
+ grh->sgid_index && grh->sgid_index < ARRAY_SIZE(ibp->guids) ?
+ ibp->guids[grh->sgid_index - 1] : ppd_from_ibp(ibp)->guid;
+ hdr->dgid = grh->dgid;
+
+ /* GRH header size in 32-bit words. */
+ return sizeof(struct ib_grh) / sizeof(u32);
+}
+
+/*
+ * free_ahg - clear ahg from QP
+ */
+void clear_ahg(struct hfi1_qp *qp)
+{
+ qp->s_hdr->ahgcount = 0;
+ qp->s_flags &= ~(HFI1_S_AHG_VALID | HFI1_S_AHG_CLEAR);
+ if (qp->s_sde)
+ sdma_ahg_free(qp->s_sde, qp->s_ahgidx);
+ qp->s_ahgidx = -1;
+ qp->s_sde = NULL;
+}
+
+#define BTH2_OFFSET (offsetof(struct hfi1_pio_header, hdr.u.oth.bth[2]) / 4)
+
+/**
+ * build_ahg - create ahg in s_hdr
+ * @qp: a pointer to QP
+ * @npsn: the next PSN for the request/response
+ *
+ * This routine handles the AHG by allocating an ahg entry and causing the
+ * copy of the first middle.
+ *
+ * Subsequent middles use the copied entry, editing the
+ * PSN with 1 or 2 edits.
+ */
+static inline void build_ahg(struct hfi1_qp *qp, u32 npsn)
+{
+ if (unlikely(qp->s_flags & HFI1_S_AHG_CLEAR))
+ clear_ahg(qp);
+ if (!(qp->s_flags & HFI1_S_AHG_VALID)) {
+ /* first middle that needs copy */
+ if (qp->s_ahgidx < 0) {
+ if (!qp->s_sde)
+ qp->s_sde = qp_to_sdma_engine(qp, qp->s_sc);
+ qp->s_ahgidx = sdma_ahg_alloc(qp->s_sde);
+ }
+ if (qp->s_ahgidx >= 0) {
+ qp->s_ahgpsn = npsn;
+ qp->s_hdr->tx_flags |= SDMA_TXREQ_F_AHG_COPY;
+ /* save to protect a change in another thread */
+ qp->s_hdr->sde = qp->s_sde;
+ qp->s_hdr->ahgidx = qp->s_ahgidx;
+ qp->s_flags |= HFI1_S_AHG_VALID;
+ }
+ } else {
+ /* subsequent middle after valid */
+ if (qp->s_ahgidx >= 0) {
+ qp->s_hdr->tx_flags |= SDMA_TXREQ_F_USE_AHG;
+ qp->s_hdr->ahgidx = qp->s_ahgidx;
+ qp->s_hdr->ahgcount++;
+ qp->s_hdr->ahgdesc[0] =
+ sdma_build_ahg_descriptor(
+ (__force u16)cpu_to_be16((u16)npsn),
+ BTH2_OFFSET,
+ 16,
+ 16);
+ if ((npsn & 0xffff0000) !=
+ (qp->s_ahgpsn & 0xffff0000)) {
+ qp->s_hdr->ahgcount++;
+ qp->s_hdr->ahgdesc[1] =
+ sdma_build_ahg_descriptor(
+ (__force u16)cpu_to_be16(
+ (u16)(npsn >> 16)),
+ BTH2_OFFSET,
+ 0,
+ 16);
+ }
+ }
+ }
+}
+
+void hfi1_make_ruc_header(struct hfi1_qp *qp, struct hfi1_other_headers *ohdr,
+ u32 bth0, u32 bth2, int middle)
+{
+ struct hfi1_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
+ u16 lrh0;
+ u32 nwords;
+ u32 extra_bytes;
+ u8 sc5;
+
+ /* Construct the header. */
+ extra_bytes = -qp->s_cur_size & 3;
+ nwords = (qp->s_cur_size + extra_bytes) >> 2;
+ lrh0 = HFI1_LRH_BTH;
+ if (unlikely(qp->remote_ah_attr.ah_flags & IB_AH_GRH)) {
+ qp->s_hdrwords += hfi1_make_grh(ibp, &qp->s_hdr->ibh.u.l.grh,
+ &qp->remote_ah_attr.grh,
+ qp->s_hdrwords, nwords);
+ lrh0 = HFI1_LRH_GRH;
+ middle = 0;
+ }
+ sc5 = ibp->sl_to_sc[qp->remote_ah_attr.sl];
+ lrh0 |= (sc5 & 0xf) << 12 | (qp->remote_ah_attr.sl & 0xf) << 4;
+ qp->s_sc = sc5;
+ /*
+ * reset s_hdr/AHG fields
+ *
+ * This insures that the ahgentry/ahgcount
+ * are at a non-AHG default to protect
+ * build_verbs_tx_desc() from using
+ * an include ahgidx.
+ *
+ * build_ahg() will modify as appropriate
+ * to use the AHG feature.
+ */
+ qp->s_hdr->tx_flags = 0;
+ qp->s_hdr->ahgcount = 0;
+ qp->s_hdr->ahgidx = 0;
+ qp->s_hdr->sde = NULL;
+ if (qp->s_mig_state == IB_MIG_MIGRATED)
+ bth0 |= IB_BTH_MIG_REQ;
+ else
+ middle = 0;
+ if (middle)
+ build_ahg(qp, bth2);
+ else
+ qp->s_flags &= ~HFI1_S_AHG_VALID;
+ qp->s_hdr->ibh.lrh[0] = cpu_to_be16(lrh0);
+ qp->s_hdr->ibh.lrh[1] = cpu_to_be16(qp->remote_ah_attr.dlid);
+ qp->s_hdr->ibh.lrh[2] =
+ cpu_to_be16(qp->s_hdrwords + nwords + SIZE_OF_CRC);
+ qp->s_hdr->ibh.lrh[3] = cpu_to_be16(ppd_from_ibp(ibp)->lid |
+ qp->remote_ah_attr.src_path_bits);
+ bth0 |= hfi1_get_pkey(ibp, qp->s_pkey_index);
+ bth0 |= extra_bytes << 20;
+ ohdr->bth[0] = cpu_to_be32(bth0);
+ ohdr->bth[1] = cpu_to_be32(qp->remote_qpn);
+ if (test_and_clear_bit(HFI1_S_ECN, &qp->s_aflags))
+ /* we recently received a FECN, so return a BECN */
+ ohdr->bth[1] |= cpu_to_be32(HFI1_BECN_MASK << HFI1_BECN_SHIFT);
+ ohdr->bth[2] = cpu_to_be32(bth2);
+}
+
+/**
+ * hfi1_do_send - perform a send on a QP
+ * @work: contains a pointer to the QP
+ *
+ * Process entries in the send work queue until credit or queue is
+ * exhausted. Only allow one CPU to send a packet per QP (tasklet).
+ * Otherwise, two threads could send packets out of order.
+ */
+void hfi1_do_send(struct work_struct *work)
+{
+ struct iowait *wait = container_of(work, struct iowait, iowork);
+ struct hfi1_qp *qp = container_of(wait, struct hfi1_qp, s_iowait);
+ struct hfi1_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
+ struct hfi1_pportdata *ppd = ppd_from_ibp(ibp);
+ int (*make_req)(struct hfi1_qp *qp);
+ unsigned long flags;
+
+ if ((qp->ibqp.qp_type == IB_QPT_RC ||
+ qp->ibqp.qp_type == IB_QPT_UC) &&
+ !loopback &&
+ (qp->remote_ah_attr.dlid & ~((1 << ppd->lmc) - 1)) == ppd->lid) {
+ ruc_loopback(qp);
+ return;
+ }
+
+ if (qp->ibqp.qp_type == IB_QPT_RC)
+ make_req = hfi1_make_rc_req;
+ else if (qp->ibqp.qp_type == IB_QPT_UC)
+ make_req = hfi1_make_uc_req;
+ else
+ make_req = hfi1_make_ud_req;
+
+ spin_lock_irqsave(&qp->s_lock, flags);
+
+ /* Return if we are already busy processing a work request. */
+ if (!hfi1_send_ok(qp)) {
+ spin_unlock_irqrestore(&qp->s_lock, flags);
+ return;
+ }
+
+ qp->s_flags |= HFI1_S_BUSY;
+
+ spin_unlock_irqrestore(&qp->s_lock, flags);
+
+ do {
+ /* Check for a constructed packet to be sent. */
+ if (qp->s_hdrwords != 0) {
+ /*
+ * If the packet cannot be sent now, return and
+ * the send tasklet will be woken up later.
+ */
+ if (hfi1_verbs_send(qp, qp->s_hdr, qp->s_hdrwords,
+ qp->s_cur_sge, qp->s_cur_size))
+ break;
+ /* Record that s_hdr is empty. */
+ qp->s_hdrwords = 0;
+ }
+ } while (make_req(qp));
+}
+
+/*
+ * This should be called with s_lock held.
+ */
+void hfi1_send_complete(struct hfi1_qp *qp, struct hfi1_swqe *wqe,
+ enum ib_wc_status status)
+{
+ u32 old_last, last;
+ unsigned i;
+
+ if (!(ib_hfi1_state_ops[qp->state] & HFI1_PROCESS_OR_FLUSH_SEND))
+ return;
+
+ for (i = 0; i < wqe->wr.num_sge; i++) {
+ struct hfi1_sge *sge = &wqe->sg_list[i];
+
+ hfi1_put_mr(sge->mr);
+ }
+ if (qp->ibqp.qp_type == IB_QPT_UD ||
+ qp->ibqp.qp_type == IB_QPT_SMI ||
+ qp->ibqp.qp_type == IB_QPT_GSI)
+ atomic_dec(&to_iah(wqe->wr.wr.ud.ah)->refcount);
+
+ /* See ch. 11.2.4.1 and 10.7.3.1 */
+ if (!(qp->s_flags & HFI1_S_SIGNAL_REQ_WR) ||
+ (wqe->wr.send_flags & IB_SEND_SIGNALED) ||
+ status != IB_WC_SUCCESS) {
+ struct ib_wc wc;
+
+ memset(&wc, 0, sizeof(wc));
+ wc.wr_id = wqe->wr.wr_id;
+ wc.status = status;
+ wc.opcode = ib_hfi1_wc_opcode[wqe->wr.opcode];
+ wc.qp = &qp->ibqp;
+ if (status == IB_WC_SUCCESS)
+ wc.byte_len = wqe->length;
+ hfi1_cq_enter(to_icq(qp->ibqp.send_cq), &wc,
+ status != IB_WC_SUCCESS);
+ }
+
+ last = qp->s_last;
+ old_last = last;
+ if (++last >= qp->s_size)
+ last = 0;
+ qp->s_last = last;
+ if (qp->s_acked == old_last)
+ qp->s_acked = last;
+ if (qp->s_cur == old_last)
+ qp->s_cur = last;
+ if (qp->s_tail == old_last)
+ qp->s_tail = last;
+ if (qp->state == IB_QPS_SQD && last == qp->s_cur)
+ qp->s_draining = 0;
+}