/*
 * Copyright(c) 2015 - 2018 Intel Corporation.
 *
 * 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
 *
 * 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
 *
 * 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 "hfi.h"
#include "verbs_txreq.h"
#include "qp.h"

/* cut down ridiculously long IB macro names */
#define OP(x) UC_OP(x)

/**
 * hfi1_make_uc_req - construct a request packet (SEND, RDMA write)
 * @qp: a pointer to the QP
 * @ps: the current packet state
 *
 * Assume s_lock is held.
 *
 * Return 1 if constructed; otherwise, return 0.
 */
int hfi1_make_uc_req(struct rvt_qp *qp, struct hfi1_pkt_state *ps)
{
        struct hfi1_qp_priv *priv = qp->priv;
        struct ib_other_headers *ohdr;
        struct rvt_swqe *wqe;
        u32 hwords;
        u32 bth0 = 0;
        u32 len;
        u32 pmtu = qp->pmtu;
        int middle = 0;

        ps->s_txreq = get_txreq(ps->dev, qp);
        if (!ps->s_txreq)
                goto bail_no_tx;

        if (!(ib_rvt_state_ops[qp->state] & RVT_PROCESS_SEND_OK)) {
                if (!(ib_rvt_state_ops[qp->state] & RVT_FLUSH_SEND))
                        goto bail;
                /* We are in the error state, flush the work request. */
                if (qp->s_last == READ_ONCE(qp->s_head))
                        goto bail;
                /* If DMAs are in progress, we can't flush immediately. */
                if (iowait_sdma_pending(&priv->s_iowait)) {
                        qp->s_flags |= RVT_S_WAIT_DMA;
                        goto bail;
                }
                clear_ahg(qp);
                wqe = rvt_get_swqe_ptr(qp, qp->s_last);
                rvt_send_complete(qp, wqe, IB_WC_WR_FLUSH_ERR);
                goto done_free_tx;
        }

        if (priv->hdr_type == HFI1_PKT_TYPE_9B) {
                /* header size in 32-bit words LRH+BTH = (8+12)/4. */
                hwords = 5;
                if (rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH)
                        ohdr = &ps->s_txreq->phdr.hdr.ibh.u.l.oth;
                else
                        ohdr = &ps->s_txreq->phdr.hdr.ibh.u.oth;
        } else {
                /* header size in 32-bit words 16B LRH+BTH = (16+12)/4. */
                hwords = 7;
                if ((rdma_ah_get_ah_flags(&qp->remote_ah_attr) & IB_AH_GRH) &&
                    (hfi1_check_mcast(rdma_ah_get_dlid(&qp->remote_ah_attr))))
                        ohdr = &ps->s_txreq->phdr.hdr.opah.u.l.oth;
                else
                        ohdr = &ps->s_txreq->phdr.hdr.opah.u.oth;
        }

        /* Get the next send request. */
        wqe = rvt_get_swqe_ptr(qp, qp->s_cur);
        qp->s_wqe = NULL;
        switch (qp->s_state) {
        default:
                if (!(ib_rvt_state_ops[qp->state] &
                    RVT_PROCESS_NEXT_SEND_OK))
                        goto bail;
                /* Check if send work queue is empty. */
                if (qp->s_cur == READ_ONCE(qp->s_head)) {
                        clear_ahg(qp);
                        goto bail;
                }
                /*
                 * Local operations are processed immediately
                 * after all prior requests have completed.
                 */
                if (wqe->wr.opcode == IB_WR_REG_MR ||
                    wqe->wr.opcode == IB_WR_LOCAL_INV) {
                        int local_ops = 0;
                        int err = 0;

                        if (qp->s_last != qp->s_cur)
                                goto bail;
                        if (++qp->s_cur == qp->s_size)
                                qp->s_cur = 0;
                        if (!(wqe->wr.send_flags & RVT_SEND_COMPLETION_ONLY)) {
                                err = rvt_invalidate_rkey(
                                        qp, wqe->wr.ex.invalidate_rkey);
                                local_ops = 1;
                        }
                        rvt_send_complete(qp, wqe, err ? IB_WC_LOC_PROT_ERR
                                                        : IB_WC_SUCCESS);
                        if (local_ops)
                                atomic_dec(&qp->local_ops_pending);
                        goto done_free_tx;
                }
                /*
                 * Start a new request.
                 */
                qp->s_psn = wqe->psn;
                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_sge.total_len = wqe->length;
                len = wqe->length;
                qp->s_len = len;
                switch (wqe->wr.opcode) {
                case IB_WR_SEND:
                case IB_WR_SEND_WITH_IMM:
                        if (len > 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 |= IB_BTH_SOLICITED;
                        qp->s_wqe = wqe;
                        if (++qp->s_cur >= qp->s_size)
                                qp->s_cur = 0;
                        break;

                case IB_WR_RDMA_WRITE:
                case IB_WR_RDMA_WRITE_WITH_IMM:
                        ohdr->u.rc.reth.vaddr =
                                cpu_to_be64(wqe->rdma_wr.remote_addr);
                        ohdr->u.rc.reth.rkey =
                                cpu_to_be32(wqe->rdma_wr.rkey);
                        ohdr->u.rc.reth.length = cpu_to_be32(len);
                        hwords += sizeof(struct ib_reth) / 4;
                        if (len > 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 the RETH */
                                ohdr->u.rc.imm_data = wqe->wr.ex.imm_data;
                                hwords += 1;
                                if (wqe->wr.send_flags & IB_SEND_SOLICITED)
                                        bth0 |= IB_BTH_SOLICITED;
                        }
                        qp->s_wqe = wqe;
                        if (++qp->s_cur >= qp->s_size)
                                qp->s_cur = 0;
                        break;

                default:
                        goto bail;
                }
                break;

        case OP(SEND_FIRST):
                qp->s_state = OP(SEND_MIDDLE);
                fallthrough;
        case OP(SEND_MIDDLE):
                len = qp->s_len;
                if (len > pmtu) {
                        len = pmtu;
                        middle = HFI1_CAP_IS_KSET(SDMA_AHG);
                        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 |= IB_BTH_SOLICITED;
                qp->s_wqe = wqe;
                if (++qp->s_cur >= qp->s_size)
                        qp->s_cur = 0;
                break;

        case OP(RDMA_WRITE_FIRST):
                qp->s_state = OP(RDMA_WRITE_MIDDLE);
                fallthrough;
        case OP(RDMA_WRITE_MIDDLE):
                len = qp->s_len;
                if (len > pmtu) {
                        len = pmtu;
                        middle = HFI1_CAP_IS_KSET(SDMA_AHG);
                        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 |= IB_BTH_SOLICITED;
                }
                qp->s_wqe = wqe;
                if (++qp->s_cur >= qp->s_size)
                        qp->s_cur = 0;
                break;
        }
        qp->s_len -= len;
        ps->s_txreq->hdr_dwords = hwords;
        ps->s_txreq->sde = priv->s_sde;
        ps->s_txreq->ss = &qp->s_sge;
        ps->s_txreq->s_cur_size = len;
        hfi1_make_ruc_header(qp, ohdr, bth0 | (qp->s_state << 24),
                             qp->remote_qpn, mask_psn(qp->s_psn++),
                             middle, ps);
        return 1;

done_free_tx:
        hfi1_put_txreq(ps->s_txreq);
        ps->s_txreq = NULL;
        return 1;

bail:
        hfi1_put_txreq(ps->s_txreq);

bail_no_tx:
        ps->s_txreq = NULL;
        qp->s_flags &= ~RVT_S_BUSY;
        return 0;
}

/**
 * hfi1_uc_rcv - handle an incoming UC packet
 * @packet: the packet structure
 *
 * This is called from qp_rcv() to process an incoming UC packet
 * for the given QP.
 * Called at interrupt level.
 */
void hfi1_uc_rcv(struct hfi1_packet *packet)
{
        struct hfi1_ibport *ibp = rcd_to_iport(packet->rcd);
        void *data = packet->payload;
        u32 tlen = packet->tlen;
        struct rvt_qp *qp = packet->qp;
        struct ib_other_headers *ohdr = packet->ohdr;
        u32 opcode = packet->opcode;
        u32 hdrsize = packet->hlen;
        u32 psn;
        u32 pad = packet->pad;
        struct ib_wc wc;
        u32 pmtu = qp->pmtu;
        struct ib_reth *reth;
        int ret;
        u8 extra_bytes = pad + packet->extra_byte + (SIZE_OF_CRC << 2);

        if (hfi1_ruc_check_hdr(ibp, packet))
                return;

        process_ecn(qp, packet);

        psn = ib_bth_get_psn(ohdr);
        /* Compare the PSN verses the expected PSN. */
        if (unlikely(cmp_psn(psn, qp->r_psn) != 0)) {
                /*
                 * Handle a sequence error.
                 * Silently drop any current message.
                 */
                qp->r_psn = psn;
inv:
                if (qp->r_state == OP(SEND_FIRST) ||
                    qp->r_state == OP(SEND_MIDDLE)) {
                        set_bit(RVT_R_REWIND_SGE, &qp->r_aflags);
                        qp->r_sge.num_sge = 0;
                } else {
                        rvt_put_ss(&qp->r_sge);
                }
                qp->r_state = OP(SEND_LAST);
                switch (opcode) {
                case OP(SEND_FIRST):
                case OP(SEND_ONLY):
                case OP(SEND_ONLY_WITH_IMMEDIATE):
                        goto send_first;

                case OP(RDMA_WRITE_FIRST):
                case OP(RDMA_WRITE_ONLY):
                case OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE):
                        goto rdma_first;

                default:
                        goto drop;
                }
        }

        /* 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 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 inv;

        default:
                if (opcode == OP(SEND_FIRST) ||
                    opcode == OP(SEND_ONLY) ||
                    opcode == OP(SEND_ONLY_WITH_IMMEDIATE) ||
                    opcode == OP(RDMA_WRITE_FIRST) ||
                    opcode == OP(RDMA_WRITE_ONLY) ||
                    opcode == OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE))
                        break;
                goto inv;
        }

        if (qp->state == IB_QPS_RTR && !(qp->r_flags & RVT_R_COMM_EST))
                rvt_comm_est(qp);

        /* OK, process the packet. */
        switch (opcode) {
        case OP(SEND_FIRST):
        case OP(SEND_ONLY):
        case OP(SEND_ONLY_WITH_IMMEDIATE):
send_first:
                if (test_and_clear_bit(RVT_R_REWIND_SGE, &qp->r_aflags)) {
                        qp->r_sge = qp->s_rdma_read_sge;
                } else {
                        ret = rvt_get_rwqe(qp, false);
                        if (ret < 0)
                                goto op_err;
                        if (!ret)
                                goto drop;
                        /*
                         * qp->s_rdma_read_sge will be the owner
                         * of the mr references.
                         */
                        qp->s_rdma_read_sge = qp->r_sge;
                }
                qp->r_rcv_len = 0;
                if (opcode == OP(SEND_ONLY))
                        goto no_immediate_data;
                else if (opcode == OP(SEND_ONLY_WITH_IMMEDIATE))
                        goto send_last_imm;
                fallthrough;
        case OP(SEND_MIDDLE):
                /* Check for invalid length PMTU or posted rwqe len. */
                /*
                 * There will be no padding for 9B packet but 16B packets
                 * will come in with some padding since we always add
                 * CRC and LT bytes which will need to be flit aligned
                 */
                if (unlikely(tlen != (hdrsize + pmtu + extra_bytes)))
                        goto rewind;
                qp->r_rcv_len += pmtu;
                if (unlikely(qp->r_rcv_len > qp->r_len))
                        goto rewind;
                rvt_copy_sge(qp, &qp->r_sge, data, pmtu, false, false);
                break;

        case OP(SEND_LAST_WITH_IMMEDIATE):
send_last_imm:
                wc.ex.imm_data = ohdr->u.imm_data;
                wc.wc_flags = IB_WC_WITH_IMM;
                goto send_last;
        case OP(SEND_LAST):
no_immediate_data:
                wc.ex.imm_data = 0;
                wc.wc_flags = 0;
send_last:
                /* Check for invalid length. */
                /* LAST len should be >= 1 */
                if (unlikely(tlen < (hdrsize + extra_bytes)))
                        goto rewind;
                /* Don't count the CRC. */
                tlen -= (hdrsize + extra_bytes);
                wc.byte_len = tlen + qp->r_rcv_len;
                if (unlikely(wc.byte_len > qp->r_len))
                        goto rewind;
                wc.opcode = IB_WC_RECV;
                rvt_copy_sge(qp, &qp->r_sge, data, tlen, false, false);
                rvt_put_ss(&qp->s_rdma_read_sge);
last_imm:
                wc.wr_id = qp->r_wr_id;
                wc.status = IB_WC_SUCCESS;
                wc.qp = &qp->ibqp;
                wc.src_qp = qp->remote_qpn;
                wc.slid = rdma_ah_get_dlid(&qp->remote_ah_attr) & U16_MAX;
                /*
                 * It seems that IB mandates the presence of an SL in a
                 * work completion only for the UD transport (see section
                 * 11.4.2 of IBTA Vol. 1).
                 *
                 * However, the way the SL is chosen below is consistent
                 * with the way that IB/qib works and is trying avoid
                 * introducing incompatibilities.
                 *
                 * See also OPA Vol. 1, section 9.7.6, and table 9-17.
                 */
                wc.sl = rdma_ah_get_sl(&qp->remote_ah_attr);
                /* zero fields that are N/A */
                wc.vendor_err = 0;
                wc.pkey_index = 0;
                wc.dlid_path_bits = 0;
                wc.port_num = 0;
                /* Signal completion event if the solicited bit is set. */
                rvt_recv_cq(qp, &wc, ib_bth_is_solicited(ohdr));
                break;

        case OP(RDMA_WRITE_FIRST):
        case OP(RDMA_WRITE_ONLY):
        case OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE): /* consume RWQE */
rdma_first:
                if (unlikely(!(qp->qp_access_flags &
                               IB_ACCESS_REMOTE_WRITE))) {
                        goto drop;
                }
                reth = &ohdr->u.rc.reth;
                qp->r_len = be32_to_cpu(reth->length);
                qp->r_rcv_len = 0;
                qp->r_sge.sg_list = NULL;
                if (qp->r_len != 0) {
                        u32 rkey = be32_to_cpu(reth->rkey);
                        u64 vaddr = be64_to_cpu(reth->vaddr);
                        int ok;

                        /* Check rkey */
                        ok = rvt_rkey_ok(qp, &qp->r_sge.sge, qp->r_len,
                                         vaddr, rkey, IB_ACCESS_REMOTE_WRITE);
                        if (unlikely(!ok))
                                goto drop;
                        qp->r_sge.num_sge = 1;
                } else {
                        qp->r_sge.num_sge = 0;
                        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_ONLY)) {
                        goto rdma_last;
                } else if (opcode == OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE)) {
                        wc.ex.imm_data = ohdr->u.rc.imm_data;
                        goto rdma_last_imm;
                }
                fallthrough;
        case OP(RDMA_WRITE_MIDDLE):
                /* Check for invalid length PMTU or posted rwqe len. */
                if (unlikely(tlen != (hdrsize + pmtu + 4)))
                        goto drop;
                qp->r_rcv_len += pmtu;
                if (unlikely(qp->r_rcv_len > qp->r_len))
                        goto drop;
                rvt_copy_sge(qp, &qp->r_sge, data, pmtu, true, false);
                break;

        case OP(RDMA_WRITE_LAST_WITH_IMMEDIATE):
                wc.ex.imm_data = ohdr->u.imm_data;
rdma_last_imm:
                wc.wc_flags = IB_WC_WITH_IMM;

                /* Check for invalid length. */
                /* LAST len should be >= 1 */
                if (unlikely(tlen < (hdrsize + pad + 4)))
                        goto drop;
                /* Don't count the CRC. */
                tlen -= (hdrsize + extra_bytes);
                if (unlikely(tlen + qp->r_rcv_len != qp->r_len))
                        goto drop;
                if (test_and_clear_bit(RVT_R_REWIND_SGE, &qp->r_aflags)) {
                        rvt_put_ss(&qp->s_rdma_read_sge);
                } else {
                        ret = rvt_get_rwqe(qp, true);
                        if (ret < 0)
                                goto op_err;
                        if (!ret)
                                goto drop;
                }
                wc.byte_len = qp->r_len;
                wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
                rvt_copy_sge(qp, &qp->r_sge, data, tlen, true, false);
                rvt_put_ss(&qp->r_sge);
                goto last_imm;

        case OP(RDMA_WRITE_LAST):
rdma_last:
                /* Check for invalid length. */
                /* LAST len should be >= 1 */
                if (unlikely(tlen < (hdrsize + pad + 4)))
                        goto drop;
                /* Don't count the CRC. */
                tlen -= (hdrsize + extra_bytes);
                if (unlikely(tlen + qp->r_rcv_len != qp->r_len))
                        goto drop;
                rvt_copy_sge(qp, &qp->r_sge, data, tlen, true, false);
                rvt_put_ss(&qp->r_sge);
                break;

        default:
                /* Drop packet for unknown opcodes. */
                goto drop;
        }
        qp->r_psn++;
        qp->r_state = opcode;
        return;

rewind:
        set_bit(RVT_R_REWIND_SGE, &qp->r_aflags);
        qp->r_sge.num_sge = 0;
drop:
        ibp->rvp.n_pkt_drops++;
        return;

op_err:
        rvt_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
}