ipath_uc.c

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/*
 * 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 "ipath_verbs.h"
#include "ipath_kernel.h"

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

int ipath_make_uc_req(struct ipath_qp *qp)
{
    struct ipath_other_headers *ohdr;
    struct ipath_swqe *wqe;
    unsigned long flags;
    u32 hwords;
    u32 bth0;
    u32 len;
    u32 pmtu = ib_mtu_enum_to_int(qp->path_mtu);
    int ret = 0;

    spin_lock_irqsave(&qp->s_lock, flags);

    if (!(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_SEND_OK)) {
        if (!(ib_ipath_state_ops[qp->state] & IPATH_FLUSH_SEND))
            goto bail;
        /* We are in the error state, flush the work request. */
        if (qp->s_last == qp->s_head)
            goto bail;
        /* If DMAs are in progress, we can't flush immediately. */
        if (atomic_read(&qp->s_dma_busy)) {
            qp->s_flags |= IPATH_S_WAIT_DMA;
            goto bail;
        }
        wqe = get_swqe_ptr(qp, qp->s_last);
        ipath_send_complete(qp, wqe, IB_WC_WR_FLUSH_ERR);
        goto done;
    }

    ohdr = &qp->s_hdr.u.oth;
    if (qp->remote_ah_attr.ah_flags & IB_AH_GRH)
        ohdr = &qp->s_hdr.u.l.oth;

    /* header size in 32-bit words LRH+BTH = (8+12)/4. */
    hwords = 5;
    bth0 = 1 << 22; /* Set M bit */

    /* Get the next send request. */
    wqe = get_swqe_ptr(qp, qp->s_cur);
    qp->s_wqe = NULL;
    switch (qp->s_state) {
    default:
        if (!(ib_ipath_state_ops[qp->state] &
            IPATH_PROCESS_NEXT_SEND_OK))
            goto bail;
        /* Check if send work queue is empty. */
        if (qp->s_cur == qp->s_head)
            goto bail;
        /*
         * Start a new request.
         */
        qp->s_psn = wqe->psn = qp->s_next_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_len = len = wqe->length;
        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 |= 1 << 23;
            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->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) / 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 |= 1 << 23;
            }
            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;
            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;
        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;
            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;
        }
        qp->s_wqe = wqe;
        if (++qp->s_cur >= qp->s_size)
            qp->s_cur = 0;
        break;
    }
    qp->s_len -= len;
    qp->s_hdrwords = hwords;
    qp->s_cur_sge = &qp->s_sge;
    qp->s_cur_size = len;
    ipath_make_ruc_header(to_idev(qp->ibqp.device),
                  qp, ohdr, bth0 | (qp->s_state << 24),
                  qp->s_next_psn++ & IPATH_PSN_MASK);
done:
    ret = 1;
    goto unlock;

bail:
    qp->s_flags &= ~IPATH_S_BUSY;
unlock:
    spin_unlock_irqrestore(&qp->s_lock, flags);
    return ret;
}

void ipath_uc_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;
    int opcode;
    u32 hdrsize;
    u32 psn;
    u32 pad;
    struct ib_wc wc;
    u32 pmtu = ib_mtu_enum_to_int(qp->path_mtu);
    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]);
    }
    /*
     * The opcode is in the low byte when its in network order
     * (top byte when in host order).
     */
    opcode = be32_to_cpu(ohdr->bth[0]) >> 24;

    memset(&wc, 0, sizeof wc);

    /* Compare the PSN verses the expected PSN. */
    if (unlikely(ipath_cmp24(psn, qp->r_psn) != 0)) {
        /*
         * Handle a sequence error.
         * Silently drop any current message.
         */
        qp->r_psn = psn;
    inv:
        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:
            dev->n_pkt_drops++;
            goto done;
        }
    }

    /* 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;
    }

    /* OK, process the packet. */
    switch (opcode) {
    case OP(SEND_FIRST):
    case OP(SEND_ONLY):
    case OP(SEND_ONLY_WITH_IMMEDIATE):
    send_first:
        if (qp->r_flags & IPATH_R_REUSE_SGE) {
            qp->r_flags &= ~IPATH_R_REUSE_SGE;
            qp->r_sge = qp->s_rdma_read_sge;
        } else if (!ipath_get_rwqe(qp, 0)) {
            dev->n_pkt_drops++;
            goto done;
        }
        /* Save the WQE so we can reuse it in case of an error. */
        qp->s_rdma_read_sge = qp->r_sge;
        qp->r_rcv_len = 0;
        if (opcode == OP(SEND_ONLY))
            goto send_last;
        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. */
        if (unlikely(tlen != (hdrsize + pmtu + 4))) {
            qp->r_flags |= IPATH_R_REUSE_SGE;
            dev->n_pkt_drops++;
            goto done;
        }
        qp->r_rcv_len += pmtu;
        if (unlikely(qp->r_rcv_len > qp->r_len)) {
            qp->r_flags |= IPATH_R_REUSE_SGE;
            dev->n_pkt_drops++;
            goto done;
        }
        ipath_copy_sge(&qp->r_sge, data, pmtu);
        break;

    case OP(SEND_LAST_WITH_IMMEDIATE):
    send_last_imm:
        if (header_in_data) {
            wc.ex.imm_data = *(__be32 *) data;
            data += sizeof(__be32);
        } else {
            /* Immediate data comes after BTH */
            wc.ex.imm_data = ohdr->u.imm_data;
        }
        hdrsize += 4;
        wc.wc_flags = IB_WC_WITH_IMM;
        /* FALLTHROUGH */
    case OP(SEND_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))) {
            qp->r_flags |= IPATH_R_REUSE_SGE;
            dev->n_pkt_drops++;
            goto done;
        }
        /* 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)) {
            qp->r_flags |= IPATH_R_REUSE_SGE;
            dev->n_pkt_drops++;
            goto done;
        }
        wc.opcode = IB_WC_RECV;
    last_imm:
        ipath_copy_sge(&qp->r_sge, data, tlen);
        wc.wr_id = qp->r_wr_id;
        wc.status = IB_WC_SUCCESS;
        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] &
                cpu_to_be32(1 << 23)) != 0);
        break;

    case OP(RDMA_WRITE_FIRST):
    case OP(RDMA_WRITE_ONLY):
    case OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE): /* consume RWQE */
    rdma_first:
        /* 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 */
            ok = ipath_rkey_ok(qp, &qp->r_sge, qp->r_len,
                       vaddr, rkey,
                       IB_ACCESS_REMOTE_WRITE);
            if (unlikely(!ok)) {
                dev->n_pkt_drops++;
                goto done;
            }
        } 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 (unlikely(!(qp->qp_access_flags &
                   IB_ACCESS_REMOTE_WRITE))) {
            dev->n_pkt_drops++;
            goto done;
        }
        if (opcode == OP(RDMA_WRITE_ONLY))
            goto rdma_last;
        else if (opcode == OP(RDMA_WRITE_ONLY_WITH_IMMEDIATE))
            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))) {
            dev->n_pkt_drops++;
            goto done;
        }
        qp->r_rcv_len += pmtu;
        if (unlikely(qp->r_rcv_len > qp->r_len)) {
            dev->n_pkt_drops++;
            goto done;
        }
        ipath_copy_sge(&qp->r_sge, data, pmtu);
        break;

    case OP(RDMA_WRITE_LAST_WITH_IMMEDIATE):
    rdma_last_imm:
        if (header_in_data) {
            wc.ex.imm_data = *(__be32 *) data;
            data += sizeof(__be32);
        } else {
            /* Immediate data comes after BTH */
            wc.ex.imm_data = ohdr->u.imm_data;
        }
        hdrsize += 4;
        wc.wc_flags = IB_WC_WITH_IMM;

        /* 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))) {
            dev->n_pkt_drops++;
            goto done;
        }
        /* Don't count the CRC. */
        tlen -= (hdrsize + pad + 4);
        if (unlikely(tlen + qp->r_rcv_len != qp->r_len)) {
            dev->n_pkt_drops++;
            goto done;
        }
        if (qp->r_flags & IPATH_R_REUSE_SGE)
            qp->r_flags &= ~IPATH_R_REUSE_SGE;
        else if (!ipath_get_rwqe(qp, 1)) {
            dev->n_pkt_drops++;
            goto done;
        }
        wc.byte_len = qp->r_len;
        wc.opcode = IB_WC_RECV_RDMA_WITH_IMM;
        goto last_imm;

    case OP(RDMA_WRITE_LAST):
    rdma_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))) {
            dev->n_pkt_drops++;
            goto done;
        }
        /* Don't count the CRC. */
        tlen -= (hdrsize + pad + 4);
        if (unlikely(tlen + qp->r_rcv_len != qp->r_len)) {
            dev->n_pkt_drops++;
            goto done;
        }
        ipath_copy_sge(&qp->r_sge, data, tlen);
        break;

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