qib_ud.c

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/*
 * Copyright (c) 2006, 2007, 2008, 2009 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 <rdma/ib_smi.h>

#include "qib.h"
#include "qib_mad.h"

static void qib_ud_loopback(struct qib_qp *sqp, struct qib_swqe *swqe)
{
    struct qib_ibport *ibp = to_iport(sqp->ibqp.device, sqp->port_num);
    struct qib_pportdata *ppd;
    struct qib_qp *qp;
    struct ib_ah_attr *ah_attr;
    unsigned long flags;
    struct qib_sge_state ssge;
    struct qib_sge *sge;
    struct ib_wc wc;
    u32 length;

    qp = qib_lookup_qpn(ibp, swqe->wr.wr.ud.remote_qpn);
    if (!qp) {
        ibp->n_pkt_drops++;
        return;
    }
    if (qp->ibqp.qp_type != sqp->ibqp.qp_type ||
        !(ib_qib_state_ops[qp->state] & QIB_PROCESS_RECV_OK)) {
        ibp->n_pkt_drops++;
        goto drop;
    }

    ah_attr = &to_iah(swqe->wr.wr.ud.ah)->attr;
    ppd = ppd_from_ibp(ibp);

    if (qp->ibqp.qp_num > 1) {
        u16 pkey1;
        u16 pkey2;
        u16 lid;

        pkey1 = qib_get_pkey(ibp, sqp->s_pkey_index);
        pkey2 = qib_get_pkey(ibp, qp->s_pkey_index);
        if (unlikely(!qib_pkey_ok(pkey1, pkey2))) {
            lid = ppd->lid | (ah_attr->src_path_bits &
                      ((1 << ppd->lmc) - 1));
            qib_bad_pqkey(ibp, IB_NOTICE_TRAP_BAD_PKEY, pkey1,
                      ah_attr->sl,
                      sqp->ibqp.qp_num, qp->ibqp.qp_num,
                      cpu_to_be16(lid),
                      cpu_to_be16(ah_attr->dlid));
            goto drop;
        }
    }

    /*
     * Check that the qkey matches (except for QP0, see 9.6.1.4.1).
     * Qkeys with the high order bit set mean use the
     * qkey from the QP context instead of the WR (see 10.2.5).
     */
    if (qp->ibqp.qp_num) {
        u32 qkey;

        qkey = (int)swqe->wr.wr.ud.remote_qkey < 0 ?
            sqp->qkey : swqe->wr.wr.ud.remote_qkey;
        if (unlikely(qkey != qp->qkey)) {
            u16 lid;

            lid = ppd->lid | (ah_attr->src_path_bits &
                      ((1 << ppd->lmc) - 1));
            qib_bad_pqkey(ibp, IB_NOTICE_TRAP_BAD_QKEY, qkey,
                      ah_attr->sl,
                      sqp->ibqp.qp_num, qp->ibqp.qp_num,
                      cpu_to_be16(lid),
                      cpu_to_be16(ah_attr->dlid));
            goto drop;
        }
    }

    /*
     * A GRH is expected to precede the data even if not
     * present on the wire.
     */
    length = swqe->length;
    memset(&wc, 0, sizeof wc);
    wc.byte_len = length + sizeof(struct ib_grh);

    if (swqe->wr.opcode == IB_WR_SEND_WITH_IMM) {
        wc.wc_flags = IB_WC_WITH_IMM;
        wc.ex.imm_data = swqe->wr.ex.imm_data;
    }

    spin_lock_irqsave(&qp->r_lock, flags);

    /*
     * Get the next work request entry to find where to put the data.
     */
    if (qp->r_flags & QIB_R_REUSE_SGE)
        qp->r_flags &= ~QIB_R_REUSE_SGE;
    else {
        int ret;

        ret = qib_get_rwqe(qp, 0);
        if (ret < 0) {
            qib_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
            goto bail_unlock;
        }
        if (!ret) {
            if (qp->ibqp.qp_num == 0)
                ibp->n_vl15_dropped++;
            goto bail_unlock;
        }
    }
    /* Silently drop packets which are too big. */
    if (unlikely(wc.byte_len > qp->r_len)) {
        qp->r_flags |= QIB_R_REUSE_SGE;
        ibp->n_pkt_drops++;
        goto bail_unlock;
    }

    if (ah_attr->ah_flags & IB_AH_GRH) {
        qib_copy_sge(&qp->r_sge, &ah_attr->grh,
                 sizeof(struct ib_grh), 1);
        wc.wc_flags |= IB_WC_GRH;
    } else
        qib_skip_sge(&qp->r_sge, sizeof(struct ib_grh), 1);
    ssge.sg_list = swqe->sg_list + 1;
    ssge.sge = *swqe->sg_list;
    ssge.num_sge = swqe->wr.num_sge;
    sge = &ssge.sge;
    while (length) {
        u32 len = sge->length;

        if (len > length)
            len = length;
        if (len > sge->sge_length)
            len = sge->sge_length;
        BUG_ON(len == 0);
        qib_copy_sge(&qp->r_sge, sge->vaddr, len, 1);
        sge->vaddr += len;
        sge->length -= len;
        sge->sge_length -= len;
        if (sge->sge_length == 0) {
            if (--ssge.num_sge)
                *sge = *ssge.sg_list++;
        } else if (sge->length == 0 && sge->mr->lkey) {
            if (++sge->n >= QIB_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;
        }
        length -= len;
    }
    qib_put_ss(&qp->r_sge);
    if (!test_and_clear_bit(QIB_R_WRID_VALID, &qp->r_aflags))
        goto bail_unlock;
    wc.wr_id = qp->r_wr_id;
    wc.status = IB_WC_SUCCESS;
    wc.opcode = IB_WC_RECV;
    wc.qp = &qp->ibqp;
    wc.src_qp = sqp->ibqp.qp_num;
    wc.pkey_index = qp->ibqp.qp_type == IB_QPT_GSI ?
        swqe->wr.wr.ud.pkey_index : 0;
    wc.slid = ppd->lid | (ah_attr->src_path_bits & ((1 << ppd->lmc) - 1));
    wc.sl = ah_attr->sl;
    wc.dlid_path_bits = ah_attr->dlid & ((1 << ppd->lmc) - 1);
    wc.port_num = qp->port_num;
    /* Signal completion event if the solicited bit is set. */
    qib_cq_enter(to_icq(qp->ibqp.recv_cq), &wc,
             swqe->wr.send_flags & IB_SEND_SOLICITED);
    ibp->n_loop_pkts++;
bail_unlock:
    spin_unlock_irqrestore(&qp->r_lock, flags);
drop:
    if (atomic_dec_and_test(&qp->refcount))
        wake_up(&qp->wait);
}

int qib_make_ud_req(struct qib_qp *qp)
{
    struct qib_other_headers *ohdr;
    struct ib_ah_attr *ah_attr;
    struct qib_pportdata *ppd;
    struct qib_ibport *ibp;
    struct qib_swqe *wqe;
    unsigned long flags;
    u32 nwords;
    u32 extra_bytes;
    u32 bth0;
    u16 lrh0;
    u16 lid;
    int ret = 0;
    int next_cur;

    spin_lock_irqsave(&qp->s_lock, flags);

    if (!(ib_qib_state_ops[qp->state] & QIB_PROCESS_NEXT_SEND_OK)) {
        if (!(ib_qib_state_ops[qp->state] & QIB_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 |= QIB_S_WAIT_DMA;
            goto bail;
        }
        wqe = get_swqe_ptr(qp, qp->s_last);
        qib_send_complete(qp, wqe, IB_WC_WR_FLUSH_ERR);
        goto done;
    }

    if (qp->s_cur == qp->s_head)
        goto bail;

    wqe = get_swqe_ptr(qp, qp->s_cur);
    next_cur = qp->s_cur + 1;
    if (next_cur >= qp->s_size)
        next_cur = 0;

    /* Construct the header. */
    ibp = to_iport(qp->ibqp.device, qp->port_num);
    ppd = ppd_from_ibp(ibp);
    ah_attr = &to_iah(wqe->wr.wr.ud.ah)->attr;
    if (ah_attr->dlid >= QIB_MULTICAST_LID_BASE) {
        if (ah_attr->dlid != QIB_PERMISSIVE_LID)
            ibp->n_multicast_xmit++;
        else
            ibp->n_unicast_xmit++;
    } else {
        ibp->n_unicast_xmit++;
        lid = ah_attr->dlid & ~((1 << ppd->lmc) - 1);
        if (unlikely(lid == ppd->lid)) {
            /*
             * If DMAs are in progress, we can't generate
             * a completion for the loopback packet since
             * it would be out of order.
             * XXX Instead of waiting, we could queue a
             * zero length descriptor so we get a callback.
             */
            if (atomic_read(&qp->s_dma_busy)) {
                qp->s_flags |= QIB_S_WAIT_DMA;
                goto bail;
            }
            qp->s_cur = next_cur;
            spin_unlock_irqrestore(&qp->s_lock, flags);
            qib_ud_loopback(qp, wqe);
            spin_lock_irqsave(&qp->s_lock, flags);
            qib_send_complete(qp, wqe, IB_WC_SUCCESS);
            goto done;
        }
    }

    qp->s_cur = next_cur;
    extra_bytes = -wqe->length & 3;
    nwords = (wqe->length + extra_bytes) >> 2;

    /* header size in 32-bit words LRH+BTH+DETH = (8+12+8)/4. */
    qp->s_hdrwords = 7;
    qp->s_cur_size = wqe->length;
    qp->s_cur_sge = &qp->s_sge;
    qp->s_srate = ah_attr->static_rate;
    qp->s_wqe = wqe;
    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;

    if (ah_attr->ah_flags & IB_AH_GRH) {
        /* Header size in 32-bit words. */
        qp->s_hdrwords += qib_make_grh(ibp, &qp->s_hdr->u.l.grh,
                           &ah_attr->grh,
                           qp->s_hdrwords, nwords);
        lrh0 = QIB_LRH_GRH;
        ohdr = &qp->s_hdr->u.l.oth;
        /*
         * Don't worry about sending to locally attached multicast
         * QPs.  It is unspecified by the spec. what happens.
         */
    } else {
        /* Header size in 32-bit words. */
        lrh0 = QIB_LRH_BTH;
        ohdr = &qp->s_hdr->u.oth;
    }
    if (wqe->wr.opcode == IB_WR_SEND_WITH_IMM) {
        qp->s_hdrwords++;
        ohdr->u.ud.imm_data = wqe->wr.ex.imm_data;
        bth0 = IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE << 24;
    } else
        bth0 = IB_OPCODE_UD_SEND_ONLY << 24;
    lrh0 |= ah_attr->sl << 4;
    if (qp->ibqp.qp_type == IB_QPT_SMI)
        lrh0 |= 0xF000; /* Set VL (see ch. 13.5.3.1) */
    else
        lrh0 |= ibp->sl_to_vl[ah_attr->sl] << 12;
    qp->s_hdr->lrh[0] = cpu_to_be16(lrh0);
    qp->s_hdr->lrh[1] = cpu_to_be16(ah_attr->dlid);  /* DEST LID */
    qp->s_hdr->lrh[2] = cpu_to_be16(qp->s_hdrwords + nwords + SIZE_OF_CRC);
    lid = ppd->lid;
    if (lid) {
        lid |= ah_attr->src_path_bits & ((1 << ppd->lmc) - 1);
        qp->s_hdr->lrh[3] = cpu_to_be16(lid);
    } else
        qp->s_hdr->lrh[3] = IB_LID_PERMISSIVE;
    if (wqe->wr.send_flags & IB_SEND_SOLICITED)
        bth0 |= IB_BTH_SOLICITED;
    bth0 |= extra_bytes << 20;
    bth0 |= qp->ibqp.qp_type == IB_QPT_SMI ? QIB_DEFAULT_P_KEY :
        qib_get_pkey(ibp, qp->ibqp.qp_type == IB_QPT_GSI ?
                 wqe->wr.wr.ud.pkey_index : qp->s_pkey_index);
    ohdr->bth[0] = cpu_to_be32(bth0);
    /*
     * Use the multicast QP if the destination LID is a multicast LID.
     */
    ohdr->bth[1] = ah_attr->dlid >= QIB_MULTICAST_LID_BASE &&
        ah_attr->dlid != QIB_PERMISSIVE_LID ?
        cpu_to_be32(QIB_MULTICAST_QPN) :
        cpu_to_be32(wqe->wr.wr.ud.remote_qpn);
    ohdr->bth[2] = cpu_to_be32(qp->s_next_psn++ & QIB_PSN_MASK);
    /*
     * Qkeys with the high order bit set mean use the
     * qkey from the QP context instead of the WR (see 10.2.5).
     */
    ohdr->u.ud.deth[0] = cpu_to_be32((int)wqe->wr.wr.ud.remote_qkey < 0 ?
                     qp->qkey : wqe->wr.wr.ud.remote_qkey);
    ohdr->u.ud.deth[1] = cpu_to_be32(qp->ibqp.qp_num);

done:
    ret = 1;
    goto unlock;

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

static unsigned qib_lookup_pkey(struct qib_ibport *ibp, u16 pkey)
{
    struct qib_pportdata *ppd = ppd_from_ibp(ibp);
    struct qib_devdata *dd = ppd->dd;
    unsigned ctxt = ppd->hw_pidx;
    unsigned i;

    pkey &= 0x7fff; /* remove limited/full membership bit */

    for (i = 0; i < ARRAY_SIZE(dd->rcd[ctxt]->pkeys); ++i)
        if ((dd->rcd[ctxt]->pkeys[i] & 0x7fff) == pkey)
            return i;

    /*
     * Should not get here, this means hardware failed to validate pkeys.
     * Punt and return index 0.
     */
    return 0;
}

void qib_ud_rcv(struct qib_ibport *ibp, struct qib_ib_header *hdr,
        int has_grh, void *data, u32 tlen, struct qib_qp *qp)
{
    struct qib_other_headers *ohdr;
    int opcode;
    u32 hdrsize;
    u32 pad;
    struct ib_wc wc;
    u32 qkey;
    u32 src_qp;
    u16 dlid;

    /* Check for GRH */
    if (!has_grh) {
        ohdr = &hdr->u.oth;
        hdrsize = 8 + 12 + 8;   /* LRH + BTH + DETH */
    } else {
        ohdr = &hdr->u.l.oth;
        hdrsize = 8 + 40 + 12 + 8; /* LRH + GRH + BTH + DETH */
    }
    qkey = be32_to_cpu(ohdr->u.ud.deth[0]);
    src_qp = be32_to_cpu(ohdr->u.ud.deth[1]) & QIB_QPN_MASK;

    /*
     * Get the number of bytes the message was padded by
     * and drop incomplete packets.
     */
    pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3;
    if (unlikely(tlen < (hdrsize + pad + 4)))
        goto drop;

    tlen -= hdrsize + pad + 4;

    /*
     * Check that the permissive LID is only used on QP0
     * and the QKEY matches (see 9.6.1.4.1 and 9.6.1.5.1).
     */
    if (qp->ibqp.qp_num) {
        if (unlikely(hdr->lrh[1] == IB_LID_PERMISSIVE ||
                 hdr->lrh[3] == IB_LID_PERMISSIVE))
            goto drop;
        if (qp->ibqp.qp_num > 1) {
            u16 pkey1, pkey2;

            pkey1 = be32_to_cpu(ohdr->bth[0]);
            pkey2 = qib_get_pkey(ibp, qp->s_pkey_index);
            if (unlikely(!qib_pkey_ok(pkey1, pkey2))) {
                qib_bad_pqkey(ibp, IB_NOTICE_TRAP_BAD_PKEY,
                          pkey1,
                          (be16_to_cpu(hdr->lrh[0]) >> 4) &
                        0xF,
                          src_qp, qp->ibqp.qp_num,
                          hdr->lrh[3], hdr->lrh[1]);
                return;
            }
        }
        if (unlikely(qkey != qp->qkey)) {
            qib_bad_pqkey(ibp, IB_NOTICE_TRAP_BAD_QKEY, qkey,
                      (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF,
                      src_qp, qp->ibqp.qp_num,
                      hdr->lrh[3], hdr->lrh[1]);
            return;
        }
        /* Drop invalid MAD packets (see 13.5.3.1). */
        if (unlikely(qp->ibqp.qp_num == 1 &&
                 (tlen != 256 ||
                  (be16_to_cpu(hdr->lrh[0]) >> 12) == 15)))
            goto drop;
    } else {
        struct ib_smp *smp;

        /* Drop invalid MAD packets (see 13.5.3.1). */
        if (tlen != 256 || (be16_to_cpu(hdr->lrh[0]) >> 12) != 15)
            goto drop;
        smp = (struct ib_smp *) data;
        if ((hdr->lrh[1] == IB_LID_PERMISSIVE ||
             hdr->lrh[3] == IB_LID_PERMISSIVE) &&
            smp->mgmt_class != IB_MGMT_CLASS_SUBN_DIRECTED_ROUTE)
            goto drop;
    }

    /*
     * 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;
    if (qp->ibqp.qp_num > 1 &&
        opcode == IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE) {
        wc.ex.imm_data = ohdr->u.ud.imm_data;
        wc.wc_flags = IB_WC_WITH_IMM;
        tlen -= sizeof(u32);
    } else if (opcode == IB_OPCODE_UD_SEND_ONLY) {
        wc.ex.imm_data = 0;
        wc.wc_flags = 0;
    } else
        goto drop;

    /*
     * A GRH is expected to precede the data even if not
     * present on the wire.
     */
    wc.byte_len = tlen + sizeof(struct ib_grh);

    /*
     * Get the next work request entry to find where to put the data.
     */
    if (qp->r_flags & QIB_R_REUSE_SGE)
        qp->r_flags &= ~QIB_R_REUSE_SGE;
    else {
        int ret;

        ret = qib_get_rwqe(qp, 0);
        if (ret < 0) {
            qib_rc_error(qp, IB_WC_LOC_QP_OP_ERR);
            return;
        }
        if (!ret) {
            if (qp->ibqp.qp_num == 0)
                ibp->n_vl15_dropped++;
            return;
        }
    }
    /* Silently drop packets which are too big. */
    if (unlikely(wc.byte_len > qp->r_len)) {
        qp->r_flags |= QIB_R_REUSE_SGE;
        goto drop;
    }
    if (has_grh) {
        qib_copy_sge(&qp->r_sge, &hdr->u.l.grh,
                 sizeof(struct ib_grh), 1);
        wc.wc_flags |= IB_WC_GRH;
    } else
        qib_skip_sge(&qp->r_sge, sizeof(struct ib_grh), 1);
    qib_copy_sge(&qp->r_sge, data, wc.byte_len - sizeof(struct ib_grh), 1);
    qib_put_ss(&qp->r_sge);
    if (!test_and_clear_bit(QIB_R_WRID_VALID, &qp->r_aflags))
        return;
    wc.wr_id = qp->r_wr_id;
    wc.status = IB_WC_SUCCESS;
    wc.opcode = IB_WC_RECV;
    wc.vendor_err = 0;
    wc.qp = &qp->ibqp;
    wc.src_qp = src_qp;
    wc.pkey_index = qp->ibqp.qp_type == IB_QPT_GSI ?
        qib_lookup_pkey(ibp, be32_to_cpu(ohdr->bth[0])) : 0;
    wc.slid = be16_to_cpu(hdr->lrh[3]);
    wc.sl = (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF;
    dlid = be16_to_cpu(hdr->lrh[1]);
    /*
     * Save the LMC lower bits if the destination LID is a unicast LID.
     */
    wc.dlid_path_bits = dlid >= QIB_MULTICAST_LID_BASE ? 0 :
        dlid & ((1 << ppd_from_ibp(ibp)->lmc) - 1);
    wc.port_num = qp->port_num;
    /* Signal completion event if the solicited bit is set. */
    qib_cq_enter(to_icq(qp->ibqp.recv_cq), &wc,
             (ohdr->bth[0] &
            cpu_to_be32(IB_BTH_SOLICITED)) != 0);
    return;

drop:
    ibp->n_pkt_drops++;
}