[net-next-2.6.git] / drivers / infiniband / hw / ipath / ipath_ud.c

/*
 * Copyright (c) 2006 QLogic, Inc. 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 "ipath_verbs.h"
#include "ipath_kernel.h"

static int init_sge(struct ipath_qp *qp, struct ipath_rwqe *wqe,
		    u32 *lengthp, struct ipath_sge_state *ss)
{
	int user = to_ipd(qp->ibqp.pd)->user;
	int i, j, ret;
	struct ib_wc wc;

	*lengthp = 0;
	for (i = j = 0; i < wqe->num_sge; i++) {
		if (wqe->sg_list[i].length == 0)
			continue;
		/* Check LKEY */
		if ((user && wqe->sg_list[i].lkey == 0) ||
		    !ipath_lkey_ok(qp, j ? &ss->sg_list[j - 1] : &ss->sge,
				   &wqe->sg_list[i], IB_ACCESS_LOCAL_WRITE))
			goto bad_lkey;
		*lengthp += wqe->sg_list[i].length;
		j++;
	}
	ss->num_sge = j;
	ret = 1;
	goto bail;

bad_lkey:
	wc.wr_id = wqe->wr_id;
	wc.status = IB_WC_LOC_PROT_ERR;
	wc.opcode = IB_WC_RECV;
	wc.vendor_err = 0;
	wc.byte_len = 0;
	wc.imm_data = 0;
	wc.qp = &qp->ibqp;
	wc.src_qp = 0;
	wc.wc_flags = 0;
	wc.pkey_index = 0;
	wc.slid = 0;
	wc.sl = 0;
	wc.dlid_path_bits = 0;
	wc.port_num = 0;
	/* Signal solicited completion event. */
	ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
	ret = 0;
bail:
	return ret;
}

/**
 * ipath_ud_loopback - handle send on loopback QPs
 * @sqp: the QP
 * @ss: the SGE state
 * @length: the length of the data to send
 * @wr: the work request
 * @wc: the work completion entry
 *
 * This is called from ipath_post_ud_send() to forward a WQE addressed
 * to the same HCA.
 * Note that the receive interrupt handler may be calling ipath_ud_rcv()
 * while this is being called.
 */
static void ipath_ud_loopback(struct ipath_qp *sqp,
			      struct ipath_sge_state *ss,
			      u32 length, struct ib_send_wr *wr,
			      struct ib_wc *wc)
{
	struct ipath_ibdev *dev = to_idev(sqp->ibqp.device);
	struct ipath_qp *qp;
	struct ib_ah_attr *ah_attr;
	unsigned long flags;
	struct ipath_rq *rq;
	struct ipath_srq *srq;
	struct ipath_sge_state rsge;
	struct ipath_sge *sge;
	struct ipath_rwq *wq;
	struct ipath_rwqe *wqe;
	void (*handler)(struct ib_event *, void *);
	u32 tail;
	u32 rlen;

	qp = ipath_lookup_qpn(&dev->qp_table, wr->wr.ud.remote_qpn);
	if (!qp)
		return;

	/*
	 * 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 (unlikely(qp->ibqp.qp_num &&
		     ((int) wr->wr.ud.remote_qkey < 0
		      ? qp->qkey : wr->wr.ud.remote_qkey) != qp->qkey)) {
		/* XXX OK to lose a count once in a while. */
		dev->qkey_violations++;
		dev->n_pkt_drops++;
		goto done;
	}

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

	if (wr->opcode == IB_WR_SEND_WITH_IMM) {
		wc->wc_flags = IB_WC_WITH_IMM;
		wc->imm_data = wr->imm_data;
	} else {
		wc->wc_flags = 0;
		wc->imm_data = 0;
	}

	if (wr->num_sge > 1) {
		rsge.sg_list = kmalloc((wr->num_sge - 1) *
					sizeof(struct ipath_sge),
				       GFP_ATOMIC);
	} else
		rsge.sg_list = NULL;

	/*
	 * Get the next work request entry to find where to put the data.
	 * Note that it is safe to drop the lock after changing rq->tail
	 * since ipath_post_receive() won't fill the empty slot.
	 */
	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);
	wq = rq->wq;
	tail = wq->tail;
	while (1) {
		if (unlikely(tail == wq->head)) {
			spin_unlock_irqrestore(&rq->lock, flags);
			dev->n_pkt_drops++;
			goto bail_sge;
		}
		wqe = get_rwqe_ptr(rq, tail);
		if (++tail >= rq->size)
			tail = 0;
		if (init_sge(qp, wqe, &rlen, &rsge))
			break;
		wq->tail = tail;
	}
	/* Silently drop packets which are too big. */
	if (wc->byte_len > rlen) {
		spin_unlock_irqrestore(&rq->lock, flags);
		dev->n_pkt_drops++;
		goto bail_sge;
	}
	wq->tail = tail;
	wc->wr_id = wqe->wr_id;
	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);
		} else
			spin_unlock_irqrestore(&rq->lock, flags);
	} else
		spin_unlock_irqrestore(&rq->lock, flags);

	ah_attr = &to_iah(wr->wr.ud.ah)->attr;
	if (ah_attr->ah_flags & IB_AH_GRH) {
		ipath_copy_sge(&rsge, &ah_attr->grh, sizeof(struct ib_grh));
		wc->wc_flags |= IB_WC_GRH;
	} else
		ipath_skip_sge(&rsge, sizeof(struct ib_grh));
	sge = &ss->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);
		ipath_copy_sge(&rsge, sge->vaddr, len);
		sge->vaddr += len;
		sge->length -= len;
		sge->sge_length -= len;
		if (sge->sge_length == 0) {
			if (--ss->num_sge)
				*sge = *ss->sg_list++;
		} else if (sge->length == 0 && sge->mr != NULL) {
			if (++sge->n >= IPATH_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;
	}
	wc->status = IB_WC_SUCCESS;
	wc->opcode = IB_WC_RECV;
	wc->vendor_err = 0;
	wc->qp = &qp->ibqp;
	wc->src_qp = sqp->ibqp.qp_num;
	/* XXX do we know which pkey matched? Only needed for GSI. */
	wc->pkey_index = 0;
	wc->slid = dev->dd->ipath_lid |
		(ah_attr->src_path_bits &
		 ((1 << (dev->mkeyprot_resv_lmc & 7)) - 1));
	wc->sl = ah_attr->sl;
	wc->dlid_path_bits =
		ah_attr->dlid & ((1 << (dev->mkeyprot_resv_lmc & 7)) - 1);
	/* Signal completion event if the solicited bit is set. */
	ipath_cq_enter(to_icq(qp->ibqp.recv_cq), wc,
		       wr->send_flags & IB_SEND_SOLICITED);

bail_sge:
	kfree(rsge.sg_list);
done:
	if (atomic_dec_and_test(&qp->refcount))
		wake_up(&qp->wait);
}

/**
 * ipath_post_ud_send - post a UD send on QP
 * @qp: the QP
 * @wr: the work request
 *
 * Note that we actually send the data as it is posted instead of putting
 * the request into a ring buffer.  If we wanted to use a ring buffer,
 * we would need to save a reference to the destination address in the SWQE.
 */
int ipath_post_ud_send(struct ipath_qp *qp, struct ib_send_wr *wr)
{
	struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
	struct ipath_other_headers *ohdr;
	struct ib_ah_attr *ah_attr;
	struct ipath_sge_state ss;
	struct ipath_sge *sg_list;
	struct ib_wc wc;
	u32 hwords;
	u32 nwords;
	u32 len;
	u32 extra_bytes;
	u32 bth0;
	u16 lrh0;
	u16 lid;
	int i;
	int ret;

	if (!(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_SEND_OK)) {
		ret = 0;
		goto bail;
	}

	if (wr->wr.ud.ah->pd != qp->ibqp.pd) {
		ret = -EPERM;
		goto bail;
	}

	/* IB spec says that num_sge == 0 is OK. */
	if (wr->num_sge > qp->s_max_sge) {
		ret = -EINVAL;
		goto bail;
	}

	if (wr->num_sge > 1) {
		sg_list = kmalloc((qp->s_max_sge - 1) * sizeof(*sg_list),
				  GFP_ATOMIC);
		if (!sg_list) {
			ret = -ENOMEM;
			goto bail;
		}
	} else
		sg_list = NULL;

	/* Check the buffer to send. */
	ss.sg_list = sg_list;
	ss.sge.mr = NULL;
	ss.sge.vaddr = NULL;
	ss.sge.length = 0;
	ss.sge.sge_length = 0;
	ss.num_sge = 0;
	len = 0;
	for (i = 0; i < wr->num_sge; i++) {
		/* Check LKEY */
		if (to_ipd(qp->ibqp.pd)->user && wr->sg_list[i].lkey == 0) {
			ret = -EINVAL;
			goto bail;
		}

		if (wr->sg_list[i].length == 0)
			continue;
		if (!ipath_lkey_ok(qp, ss.num_sge ?
				   sg_list + ss.num_sge - 1 : &ss.sge,
				   &wr->sg_list[i], 0)) {
			ret = -EINVAL;
			goto bail;
		}
		len += wr->sg_list[i].length;
		ss.num_sge++;
	}
	/* Check for invalid packet size. */
	if (len > dev->dd->ipath_ibmtu) {
		ret = -EINVAL;
		goto bail;
	}
	extra_bytes = (4 - len) & 3;
	nwords = (len + extra_bytes) >> 2;

	/* Construct the header. */
	ah_attr = &to_iah(wr->wr.ud.ah)->attr;
	if (ah_attr->dlid == 0) {
		ret = -EINVAL;
		goto bail;
	}
	if (ah_attr->dlid >= IPATH_MULTICAST_LID_BASE) {
		if (ah_attr->dlid != IPATH_PERMISSIVE_LID)
			dev->n_multicast_xmit++;
		else
			dev->n_unicast_xmit++;
	} else {
		dev->n_unicast_xmit++;
		lid = ah_attr->dlid &
			~((1 << (dev->mkeyprot_resv_lmc & 7)) - 1);
		if (unlikely(lid == dev->dd->ipath_lid)) {
			/*
			 * Pass in an uninitialized ib_wc to save stack
			 * space.
			 */
			ipath_ud_loopback(qp, &ss, len, wr, &wc);
			goto done;
		}
	}
	if (ah_attr->ah_flags & IB_AH_GRH) {
		/* Header size in 32-bit words. */
		hwords = 17;
		lrh0 = IPATH_LRH_GRH;
		ohdr = &qp->s_hdr.u.l.oth;
		qp->s_hdr.u.l.grh.version_tclass_flow =
			cpu_to_be32((6 << 28) |
				    (ah_attr->grh.traffic_class << 20) |
				    ah_attr->grh.flow_label);
		qp->s_hdr.u.l.grh.paylen =
			cpu_to_be16(((wr->opcode ==
				      IB_WR_SEND_WITH_IMM ? 6 : 5) +
				     nwords + SIZE_OF_CRC) << 2);
		/* next_hdr is defined by C8-7 in ch. 8.4.1 */
		qp->s_hdr.u.l.grh.next_hdr = 0x1B;
		qp->s_hdr.u.l.grh.hop_limit = ah_attr->grh.hop_limit;
		/* The SGID is 32-bit aligned. */
		qp->s_hdr.u.l.grh.sgid.global.subnet_prefix =
			dev->gid_prefix;
		qp->s_hdr.u.l.grh.sgid.global.interface_id =
			dev->dd->ipath_guid;
		qp->s_hdr.u.l.grh.dgid = ah_attr->grh.dgid;
		/*
		 * 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. */
		hwords = 7;
		lrh0 = IPATH_LRH_BTH;
		ohdr = &qp->s_hdr.u.oth;
	}
	if (wr->opcode == IB_WR_SEND_WITH_IMM) {
		ohdr->u.ud.imm_data = wr->imm_data;
		wc.imm_data = wr->imm_data;
		hwords += 1;
		bth0 = IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE << 24;
	} else if (wr->opcode == IB_WR_SEND) {
		wc.imm_data = 0;
		bth0 = IB_OPCODE_UD_SEND_ONLY << 24;
	} else {
		ret = -EINVAL;
		goto bail;
	}
	lrh0 |= ah_attr->sl << 4;
	if (qp->ibqp.qp_type == IB_QPT_SMI)
		lrh0 |= 0xF000;	/* Set VL (see ch. 13.5.3.1) */
	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(hwords + nwords + SIZE_OF_CRC);
	lid = dev->dd->ipath_lid;
	if (lid) {
		lid |= ah_attr->src_path_bits &
			((1 << (dev->mkeyprot_resv_lmc & 7)) - 1);
		qp->s_hdr.lrh[3] = cpu_to_be16(lid);
	} else
		qp->s_hdr.lrh[3] = IB_LID_PERMISSIVE;
	if (wr->send_flags & IB_SEND_SOLICITED)
		bth0 |= 1 << 23;
	bth0 |= extra_bytes << 20;
	bth0 |= qp->ibqp.qp_type == IB_QPT_SMI ? IPATH_DEFAULT_P_KEY :
		ipath_get_pkey(dev->dd, 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 >= IPATH_MULTICAST_LID_BASE &&
		ah_attr->dlid != IPATH_PERMISSIVE_LID ?
		__constant_cpu_to_be32(IPATH_MULTICAST_QPN) :
		cpu_to_be32(wr->wr.ud.remote_qpn);
	/* XXX Could lose a PSN count but not worth locking */
	ohdr->bth[2] = cpu_to_be32(qp->s_next_psn++ & IPATH_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)wr->wr.ud.remote_qkey < 0 ?
					 qp->qkey : wr->wr.ud.remote_qkey);
	ohdr->u.ud.deth[1] = cpu_to_be32(qp->ibqp.qp_num);
	if (ipath_verbs_send(dev->dd, hwords, (u32 *) &qp->s_hdr,
			     len, &ss))
		dev->n_no_piobuf++;

done:
	/* Queue the completion status entry. */
	if (!(qp->s_flags & IPATH_S_SIGNAL_REQ_WR) ||
	    (wr->send_flags & IB_SEND_SIGNALED)) {
		wc.wr_id = wr->wr_id;
		wc.status = IB_WC_SUCCESS;
		wc.vendor_err = 0;
		wc.opcode = IB_WC_SEND;
		wc.byte_len = len;
		wc.qp = &qp->ibqp;
		wc.src_qp = 0;
		wc.wc_flags = 0;
		/* XXX initialize other fields? */
		ipath_cq_enter(to_icq(qp->ibqp.send_cq), &wc, 0);
	}
	kfree(sg_list);

	ret = 0;

bail:
	return ret;
}

/**
 * ipath_ud_rcv - receive an incoming UD packet
 * @dev: the device the packet came in on
 * @hdr: the packet header
 * @has_grh: true if the packet has a GRH
 * @data: the packet data
 * @tlen: the packet length
 * @qp: the QP the packet came on
 *
 * This is called from ipath_qp_rcv() to process an incoming UD packet
 * for the given QP.
 * Called at interrupt level.
 */
void ipath_ud_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 pad;
	struct ib_wc wc;
	u32 qkey;
	u32 src_qp;
	u16 dlid;
	int header_in_data;

	/* Check for GRH */
	if (!has_grh) {
		ohdr = &hdr->u.oth;
		hdrsize = 8 + 12 + 8;	/* LRH + BTH + DETH */
		qkey = be32_to_cpu(ohdr->u.ud.deth[0]);
		src_qp = be32_to_cpu(ohdr->u.ud.deth[1]);
		header_in_data = 0;
	} else {
		ohdr = &hdr->u.l.oth;
		hdrsize = 8 + 40 + 12 + 8; /* LRH + GRH + BTH + DETH */
		/*
		 * The header with GRH is 68 bytes and the core driver sets
		 * the eager header buffer size to 56 bytes so the last 12
		 * bytes of the IB header is in the data buffer.
		 */
		header_in_data = dev->dd->ipath_rcvhdrentsize == 16;
		if (header_in_data) {
			qkey = be32_to_cpu(((__be32 *) data)[1]);
			src_qp = be32_to_cpu(((__be32 *) data)[2]);
			data += 12;
		} else {
			qkey = be32_to_cpu(ohdr->u.ud.deth[0]);
			src_qp = be32_to_cpu(ohdr->u.ud.deth[1]);
		}
	}
	src_qp &= IPATH_QPN_MASK;

	/*
	 * 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)) {
			dev->n_pkt_drops++;
			goto bail;
		}
		if (unlikely(qkey != qp->qkey)) {
			/* XXX OK to lose a count once in a while. */
			dev->qkey_violations++;
			dev->n_pkt_drops++;
			goto bail;
		}
	} else if (hdr->lrh[1] == IB_LID_PERMISSIVE ||
		   hdr->lrh[3] == IB_LID_PERMISSIVE) {
		struct ib_smp *smp = (struct ib_smp *) data;

		if (smp->mgmt_class != IB_MGMT_CLASS_SUBN_DIRECTED_ROUTE) {
			dev->n_pkt_drops++;
			goto bail;
		}
	}

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

	/* Drop invalid MAD packets (see 13.5.3.1). */
	if (unlikely((qp->ibqp.qp_num == 0 &&
		      (tlen != 256 ||
		       (be16_to_cpu(hdr->lrh[0]) >> 12) != 15)) ||
		     (qp->ibqp.qp_num == 1 &&
		      (tlen != 256 ||
		       (be16_to_cpu(hdr->lrh[0]) >> 12) == 15)))) {
		dev->n_pkt_drops++;
		goto bail;
	}

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

	/*
	 * 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) {
		if (header_in_data) {
			wc.imm_data = *(__be32 *) data;
			data += sizeof(__be32);
		} else
			wc.imm_data = ohdr->u.ud.imm_data;
		wc.wc_flags = IB_WC_WITH_IMM;
		hdrsize += sizeof(u32);
	} else if (opcode == IB_OPCODE_UD_SEND_ONLY) {
		wc.imm_data = 0;
		wc.wc_flags = 0;
	} else {
		dev->n_pkt_drops++;
		goto bail;
	}

	/*
	 * Get the next work request entry to find where to put the data.
	 */
	if (qp->r_reuse_sge)
		qp->r_reuse_sge = 0;
	else if (!ipath_get_rwqe(qp, 0)) {
		/*
		 * Count VL15 packets dropped due to no receive buffer.
		 * Otherwise, count them as buffer overruns since usually,
		 * the HW will be able to receive packets even if there are
		 * no QPs with posted receive buffers.
		 */
		if (qp->ibqp.qp_num == 0)
			dev->n_vl15_dropped++;
		else
			dev->rcv_errors++;
		goto bail;
	}
	/* Silently drop packets which are too big. */
	if (wc.byte_len > qp->r_len) {
		qp->r_reuse_sge = 1;
		dev->n_pkt_drops++;
		goto bail;
	}
	if (has_grh) {
		ipath_copy_sge(&qp->r_sge, &hdr->u.l.grh,
			       sizeof(struct ib_grh));
		wc.wc_flags |= IB_WC_GRH;
	} else
		ipath_skip_sge(&qp->r_sge, sizeof(struct ib_grh));
	ipath_copy_sge(&qp->r_sge, data,
		       wc.byte_len - sizeof(struct ib_grh));
	qp->r_wrid_valid = 0;
	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;
	/* XXX do we know which pkey matched? Only needed for GSI. */
	wc.pkey_index = 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 >= IPATH_MULTICAST_LID_BASE ? 0 :
		dlid & ((1 << (dev->mkeyprot_resv_lmc & 7)) - 1);
	/* 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);

bail:;
}
Commit	Line	Data
74ed6b5e	1	/*
759d5768	2	* Copyright (c) 2006 QLogic, Inc. All rights reserved.
74ed6b5e BS	3	* Copyright (c) 2005, 2006 PathScale, Inc. All rights reserved.
	4	*
	5	* This software is available to you under a choice of one of two
	6	* licenses. You may choose to be licensed under the terms of the GNU
	7	* General Public License (GPL) Version 2, available from the file
	8	* COPYING in the main directory of this source tree, or the
	9	* OpenIB.org BSD license below:
	10	*
	11	* Redistribution and use in source and binary forms, with or
	12	* without modification, are permitted provided that the following
	13	* conditions are met:
	14	*
	15	* - Redistributions of source code must retain the above
	16	* copyright notice, this list of conditions and the following
	17	* disclaimer.
	18	*
	19	* - Redistributions in binary form must reproduce the above
	20	* copyright notice, this list of conditions and the following
	21	* disclaimer in the documentation and/or other materials
	22	* provided with the distribution.
	23	*
	24	* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
	25	* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
	26	* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
	27	* NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
	28	* BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
	29	* ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
	30	* CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
	31	* SOFTWARE.
	32	*/
	33
	34	#include <rdma/ib_smi.h>
	35
	36	#include "ipath_verbs.h"
373d9915 RC	37	#include "ipath_kernel.h"
	38
	39	static int init_sge(struct ipath_qp qp, struct ipath_rwqe wqe,
	40	u32 lengthp, struct ipath_sge_state ss)
	41	{
373d9915 RC	42	int user = to_ipd(qp->ibqp.pd)->user;
	43	int i, j, ret;
	44	struct ib_wc wc;
	45
	46	*lengthp = 0;
	47	for (i = j = 0; i < wqe->num_sge; i++) {
	48	if (wqe->sg_list[i].length == 0)
	49	continue;
	50	/* Check LKEY */
	51	if ((user && wqe->sg_list[i].lkey == 0) \|\|
6a553af2	52	!ipath_lkey_ok(qp, j ? &ss->sg_list[j - 1] : &ss->sge,
373d9915 RC	53	&wqe->sg_list[i], IB_ACCESS_LOCAL_WRITE))
	54	goto bad_lkey;
	55	*lengthp += wqe->sg_list[i].length;
	56	j++;
	57	}
	58	ss->num_sge = j;
	59	ret = 1;
	60	goto bail;
	61
	62	bad_lkey:
	63	wc.wr_id = wqe->wr_id;
	64	wc.status = IB_WC_LOC_PROT_ERR;
	65	wc.opcode = IB_WC_RECV;
	66	wc.vendor_err = 0;
	67	wc.byte_len = 0;
	68	wc.imm_data = 0;
062dbb69	69	wc.qp = &qp->ibqp;
373d9915 RC	70	wc.src_qp = 0;
	71	wc.wc_flags = 0;
	72	wc.pkey_index = 0;
	73	wc.slid = 0;
	74	wc.sl = 0;
	75	wc.dlid_path_bits = 0;
	76	wc.port_num = 0;
	77	/* Signal solicited completion event. */
	78	ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
	79	ret = 0;
	80	bail:
	81	return ret;
	82	}
74ed6b5e BS	83
	84	/**
	85	* ipath_ud_loopback - handle send on loopback QPs
	86	* @sqp: the QP
	87	* @ss: the SGE state
	88	* @length: the length of the data to send
	89	* @wr: the work request
	90	* @wc: the work completion entry
	91	*
	92	* This is called from ipath_post_ud_send() to forward a WQE addressed
	93	* to the same HCA.
373d9915 RC	94	* Note that the receive interrupt handler may be calling ipath_ud_rcv()
373d9915 RC	95	* while this is being called.
74ed6b5e	96	*/
f6f0413e BS	97	static void ipath_ud_loopback(struct ipath_qp *sqp,
	98	struct ipath_sge_state *ss,
	99	u32 length, struct ib_send_wr *wr,
	100	struct ib_wc *wc)
74ed6b5e BS	101	{
	102	struct ipath_ibdev *dev = to_idev(sqp->ibqp.device);
	103	struct ipath_qp *qp;
	104	struct ib_ah_attr *ah_attr;
	105	unsigned long flags;
	106	struct ipath_rq *rq;
	107	struct ipath_srq *srq;
	108	struct ipath_sge_state rsge;
	109	struct ipath_sge *sge;
373d9915	110	struct ipath_rwq *wq;
74ed6b5e	111	struct ipath_rwqe *wqe;
373d9915 RC	112	void (handler)(struct ib_event , void *);
	113	u32 tail;
	114	u32 rlen;
74ed6b5e BS	115
	116	qp = ipath_lookup_qpn(&dev->qp_table, wr->wr.ud.remote_qpn);
	117	if (!qp)
	118	return;
	119
	120	/*
	121	* Check that the qkey matches (except for QP0, see 9.6.1.4.1).
	122	* Qkeys with the high order bit set mean use the
	123	* qkey from the QP context instead of the WR (see 10.2.5).
	124	*/
	125	if (unlikely(qp->ibqp.qp_num &&
	126	((int) wr->wr.ud.remote_qkey < 0
	127	? qp->qkey : wr->wr.ud.remote_qkey) != qp->qkey)) {
	128	/* XXX OK to lose a count once in a while. */
	129	dev->qkey_violations++;
	130	dev->n_pkt_drops++;
	131	goto done;
	132	}
	133
	134	/*
	135	* A GRH is expected to preceed the data even if not
	136	* present on the wire.
	137	*/
	138	wc->byte_len = length + sizeof(struct ib_grh);
	139
	140	if (wr->opcode == IB_WR_SEND_WITH_IMM) {
	141	wc->wc_flags = IB_WC_WITH_IMM;
	142	wc->imm_data = wr->imm_data;
	143	} else {
	144	wc->wc_flags = 0;
	145	wc->imm_data = 0;
	146	}
	147
373d9915 RC	148	if (wr->num_sge > 1) {
	149	rsge.sg_list = kmalloc((wr->num_sge - 1) *
	150	sizeof(struct ipath_sge),
	151	GFP_ATOMIC);
	152	} else
	153	rsge.sg_list = NULL;
	154
74ed6b5e BS	155	/*
	156	* Get the next work request entry to find where to put the data.
	157	* Note that it is safe to drop the lock after changing rq->tail
	158	* since ipath_post_receive() won't fill the empty slot.
	159	*/
	160	if (qp->ibqp.srq) {
	161	srq = to_isrq(qp->ibqp.srq);
373d9915	162	handler = srq->ibsrq.event_handler;
74ed6b5e BS	163	rq = &srq->rq;
	164	} else {
	165	srq = NULL;
373d9915	166	handler = NULL;
74ed6b5e BS	167	rq = &qp->r_rq;
74ed6b5e BS	168	}
373d9915	169
74ed6b5e	170	spin_lock_irqsave(&rq->lock, flags);
373d9915 RC	171	wq = rq->wq;
	172	tail = wq->tail;
	173	while (1) {
	174	if (unlikely(tail == wq->head)) {
	175	spin_unlock_irqrestore(&rq->lock, flags);
	176	dev->n_pkt_drops++;
	177	goto bail_sge;
	178	}
	179	wqe = get_rwqe_ptr(rq, tail);
	180	if (++tail >= rq->size)
	181	tail = 0;
	182	if (init_sge(qp, wqe, &rlen, &rsge))
	183	break;
	184	wq->tail = tail;
74ed6b5e BS	185	}
74ed6b5e BS	186	/* Silently drop packets which are too big. */
373d9915	187	if (wc->byte_len > rlen) {
74ed6b5e BS	188	spin_unlock_irqrestore(&rq->lock, flags);
74ed6b5e BS	189	dev->n_pkt_drops++;
373d9915	190	goto bail_sge;
74ed6b5e	191	}
373d9915	192	wq->tail = tail;
74ed6b5e	193	wc->wr_id = wqe->wr_id;
373d9915	194	if (handler) {
74ed6b5e BS	195	u32 n;
74ed6b5e BS	196
373d9915 RC	197	/*
	198	* validate head pointer value and compute
	199	* the number of remaining WQEs.
	200	*/
	201	n = wq->head;
	202	if (n >= rq->size)
	203	n = 0;
	204	if (n < tail)
	205	n += rq->size - tail;
74ed6b5e	206	else
373d9915	207	n -= tail;
74ed6b5e BS	208	if (n < srq->limit) {
	209	struct ib_event ev;
	210
	211	srq->limit = 0;
	212	spin_unlock_irqrestore(&rq->lock, flags);
	213	ev.device = qp->ibqp.device;
	214	ev.element.srq = qp->ibqp.srq;
	215	ev.event = IB_EVENT_SRQ_LIMIT_REACHED;
373d9915	216	handler(&ev, srq->ibsrq.srq_context);
74ed6b5e BS	217	} else
	218	spin_unlock_irqrestore(&rq->lock, flags);
	219	} else
	220	spin_unlock_irqrestore(&rq->lock, flags);
373d9915	221
74ed6b5e BS	222	ah_attr = &to_iah(wr->wr.ud.ah)->attr;
	223	if (ah_attr->ah_flags & IB_AH_GRH) {
	224	ipath_copy_sge(&rsge, &ah_attr->grh, sizeof(struct ib_grh));
	225	wc->wc_flags \|= IB_WC_GRH;
	226	} else
	227	ipath_skip_sge(&rsge, sizeof(struct ib_grh));
	228	sge = &ss->sge;
	229	while (length) {
	230	u32 len = sge->length;
	231
	232	if (len > length)
	233	len = length;
30d149ab RC	234	if (len > sge->sge_length)
30d149ab RC	235	len = sge->sge_length;
74ed6b5e BS	236	BUG_ON(len == 0);
	237	ipath_copy_sge(&rsge, sge->vaddr, len);
	238	sge->vaddr += len;
	239	sge->length -= len;
	240	sge->sge_length -= len;
	241	if (sge->sge_length == 0) {
	242	if (--ss->num_sge)
	243	sge = ss->sg_list++;
	244	} else if (sge->length == 0 && sge->mr != NULL) {
	245	if (++sge->n >= IPATH_SEGSZ) {
	246	if (++sge->m >= sge->mr->mapsz)
	247	break;
	248	sge->n = 0;
	249	}
	250	sge->vaddr =
	251	sge->mr->map[sge->m]->segs[sge->n].vaddr;
	252	sge->length =
	253	sge->mr->map[sge->m]->segs[sge->n].length;
	254	}
	255	length -= len;
	256	}
	257	wc->status = IB_WC_SUCCESS;
	258	wc->opcode = IB_WC_RECV;
	259	wc->vendor_err = 0;
062dbb69	260	wc->qp = &qp->ibqp;
74ed6b5e BS	261	wc->src_qp = sqp->ibqp.qp_num;
	262	/* XXX do we know which pkey matched? Only needed for GSI. */
	263	wc->pkey_index = 0;
373d9915	264	wc->slid = dev->dd->ipath_lid \|
74ed6b5e BS	265	(ah_attr->src_path_bits &
	266	((1 << (dev->mkeyprot_resv_lmc & 7)) - 1));
	267	wc->sl = ah_attr->sl;
	268	wc->dlid_path_bits =
	269	ah_attr->dlid & ((1 << (dev->mkeyprot_resv_lmc & 7)) - 1);
	270	/* Signal completion event if the solicited bit is set. */
	271	ipath_cq_enter(to_icq(qp->ibqp.recv_cq), wc,
	272	wr->send_flags & IB_SEND_SOLICITED);
	273
373d9915 RC	274	bail_sge:
373d9915 RC	275	kfree(rsge.sg_list);
74ed6b5e BS	276	done:
	277	if (atomic_dec_and_test(&qp->refcount))
	278	wake_up(&qp->wait);
	279	}
	280
	281	/**
	282	* ipath_post_ud_send - post a UD send on QP
	283	* @qp: the QP
	284	* @wr: the work request
	285	*
	286	* Note that we actually send the data as it is posted instead of putting
	287	* the request into a ring buffer. If we wanted to use a ring buffer,
	288	* we would need to save a reference to the destination address in the SWQE.
	289	*/
	290	int ipath_post_ud_send(struct ipath_qp qp, struct ib_send_wr wr)
	291	{
	292	struct ipath_ibdev *dev = to_idev(qp->ibqp.device);
	293	struct ipath_other_headers *ohdr;
	294	struct ib_ah_attr *ah_attr;
	295	struct ipath_sge_state ss;
	296	struct ipath_sge *sg_list;
	297	struct ib_wc wc;
	298	u32 hwords;
	299	u32 nwords;
	300	u32 len;
	301	u32 extra_bytes;
	302	u32 bth0;
	303	u16 lrh0;
	304	u16 lid;
	305	int i;
	306	int ret;
	307
	308	if (!(ib_ipath_state_ops[qp->state] & IPATH_PROCESS_SEND_OK)) {
	309	ret = 0;
	310	goto bail;
	311	}
	312
6ce73b07 RW	313	if (wr->wr.ud.ah->pd != qp->ibqp.pd) {
	314	ret = -EPERM;
	315	goto bail;
	316	}
	317
74ed6b5e BS	318	/* IB spec says that num_sge == 0 is OK. */
	319	if (wr->num_sge > qp->s_max_sge) {
	320	ret = -EINVAL;
	321	goto bail;
	322	}
	323
	324	if (wr->num_sge > 1) {
	325	sg_list = kmalloc((qp->s_max_sge - 1) * sizeof(*sg_list),
	326	GFP_ATOMIC);
	327	if (!sg_list) {
	328	ret = -ENOMEM;
	329	goto bail;
	330	}
	331	} else
	332	sg_list = NULL;
	333
	334	/* Check the buffer to send. */
	335	ss.sg_list = sg_list;
	336	ss.sge.mr = NULL;
	337	ss.sge.vaddr = NULL;
	338	ss.sge.length = 0;
	339	ss.sge.sge_length = 0;
	340	ss.num_sge = 0;
	341	len = 0;
	342	for (i = 0; i < wr->num_sge; i++) {
	343	/* Check LKEY */
	344	if (to_ipd(qp->ibqp.pd)->user && wr->sg_list[i].lkey == 0) {
	345	ret = -EINVAL;
	346	goto bail;
	347	}
	348
	349	if (wr->sg_list[i].length == 0)
	350	continue;
6a553af2	351	if (!ipath_lkey_ok(qp, ss.num_sge ?
74ed6b5e BS	352	sg_list + ss.num_sge - 1 : &ss.sge,
	353	&wr->sg_list[i], 0)) {
	354	ret = -EINVAL;
	355	goto bail;
	356	}
	357	len += wr->sg_list[i].length;
	358	ss.num_sge++;
	359	}
4faba98a	360	/* Check for invalid packet size. */
34b2aafe	361	if (len > dev->dd->ipath_ibmtu) {
4faba98a BS	362	ret = -EINVAL;
	363	goto bail;
	364	}
74ed6b5e BS	365	extra_bytes = (4 - len) & 3;
	366	nwords = (len + extra_bytes) >> 2;
	367
	368	/* Construct the header. */
	369	ah_attr = &to_iah(wr->wr.ud.ah)->attr;
	370	if (ah_attr->dlid == 0) {
	371	ret = -EINVAL;
	372	goto bail;
	373	}
27b678dd BS	374	if (ah_attr->dlid >= IPATH_MULTICAST_LID_BASE) {
27b678dd BS	375	if (ah_attr->dlid != IPATH_PERMISSIVE_LID)
74ed6b5e BS	376	dev->n_multicast_xmit++;
	377	else
	378	dev->n_unicast_xmit++;
	379	} else {
	380	dev->n_unicast_xmit++;
	381	lid = ah_attr->dlid &
	382	~((1 << (dev->mkeyprot_resv_lmc & 7)) - 1);
34b2aafe	383	if (unlikely(lid == dev->dd->ipath_lid)) {
74ed6b5e BS	384	/*
	385	* Pass in an uninitialized ib_wc to save stack
	386	* space.
	387	*/
	388	ipath_ud_loopback(qp, &ss, len, wr, &wc);
	389	goto done;
	390	}
	391	}
	392	if (ah_attr->ah_flags & IB_AH_GRH) {
	393	/* Header size in 32-bit words. */
	394	hwords = 17;
27b678dd	395	lrh0 = IPATH_LRH_GRH;
74ed6b5e BS	396	ohdr = &qp->s_hdr.u.l.oth;
	397	qp->s_hdr.u.l.grh.version_tclass_flow =
	398	cpu_to_be32((6 << 28) \|
	399	(ah_attr->grh.traffic_class << 20) \|
	400	ah_attr->grh.flow_label);
	401	qp->s_hdr.u.l.grh.paylen =
	402	cpu_to_be16(((wr->opcode ==
	403	IB_WR_SEND_WITH_IMM ? 6 : 5) +
	404	nwords + SIZE_OF_CRC) << 2);
	405	/* next_hdr is defined by C8-7 in ch. 8.4.1 */
	406	qp->s_hdr.u.l.grh.next_hdr = 0x1B;
	407	qp->s_hdr.u.l.grh.hop_limit = ah_attr->grh.hop_limit;
	408	/* The SGID is 32-bit aligned. */
	409	qp->s_hdr.u.l.grh.sgid.global.subnet_prefix =
	410	dev->gid_prefix;
	411	qp->s_hdr.u.l.grh.sgid.global.interface_id =
34b2aafe	412	dev->dd->ipath_guid;
74ed6b5e BS	413	qp->s_hdr.u.l.grh.dgid = ah_attr->grh.dgid;
	414	/*
	415	* Don't worry about sending to locally attached multicast
	416	* QPs. It is unspecified by the spec. what happens.
	417	*/
	418	} else {
	419	/* Header size in 32-bit words. */
	420	hwords = 7;
27b678dd	421	lrh0 = IPATH_LRH_BTH;
74ed6b5e BS	422	ohdr = &qp->s_hdr.u.oth;
	423	}
	424	if (wr->opcode == IB_WR_SEND_WITH_IMM) {
	425	ohdr->u.ud.imm_data = wr->imm_data;
	426	wc.imm_data = wr->imm_data;
	427	hwords += 1;
	428	bth0 = IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE << 24;
	429	} else if (wr->opcode == IB_WR_SEND) {
	430	wc.imm_data = 0;
	431	bth0 = IB_OPCODE_UD_SEND_ONLY << 24;
	432	} else {
	433	ret = -EINVAL;
	434	goto bail;
	435	}
	436	lrh0 \|= ah_attr->sl << 4;
	437	if (qp->ibqp.qp_type == IB_QPT_SMI)
	438	lrh0 \|= 0xF000; /* Set VL (see ch. 13.5.3.1) */
	439	qp->s_hdr.lrh[0] = cpu_to_be16(lrh0);
	440	qp->s_hdr.lrh[1] = cpu_to_be16(ah_attr->dlid); /* DEST LID */
	441	qp->s_hdr.lrh[2] = cpu_to_be16(hwords + nwords + SIZE_OF_CRC);
34b2aafe	442	lid = dev->dd->ipath_lid;
74ed6b5e BS	443	if (lid) {
	444	lid \|= ah_attr->src_path_bits &
	445	((1 << (dev->mkeyprot_resv_lmc & 7)) - 1);
	446	qp->s_hdr.lrh[3] = cpu_to_be16(lid);
	447	} else
	448	qp->s_hdr.lrh[3] = IB_LID_PERMISSIVE;
	449	if (wr->send_flags & IB_SEND_SOLICITED)
	450	bth0 \|= 1 << 23;
	451	bth0 \|= extra_bytes << 20;
27b678dd	452	bth0 \|= qp->ibqp.qp_type == IB_QPT_SMI ? IPATH_DEFAULT_P_KEY :
34b2aafe	453	ipath_get_pkey(dev->dd, qp->s_pkey_index);
74ed6b5e BS	454	ohdr->bth[0] = cpu_to_be32(bth0);
	455	/*
	456	* Use the multicast QP if the destination LID is a multicast LID.
	457	*/
27b678dd BS	458	ohdr->bth[1] = ah_attr->dlid >= IPATH_MULTICAST_LID_BASE &&
	459	ah_attr->dlid != IPATH_PERMISSIVE_LID ?
	460	__constant_cpu_to_be32(IPATH_MULTICAST_QPN) :
74ed6b5e BS	461	cpu_to_be32(wr->wr.ud.remote_qpn);
74ed6b5e BS	462	/* XXX Could lose a PSN count but not worth locking */
27b678dd	463	ohdr->bth[2] = cpu_to_be32(qp->s_next_psn++ & IPATH_PSN_MASK);
74ed6b5e BS	464	/*
	465	* Qkeys with the high order bit set mean use the
	466	* qkey from the QP context instead of the WR (see 10.2.5).
	467	*/
	468	ohdr->u.ud.deth[0] = cpu_to_be32((int)wr->wr.ud.remote_qkey < 0 ?
	469	qp->qkey : wr->wr.ud.remote_qkey);
	470	ohdr->u.ud.deth[1] = cpu_to_be32(qp->ibqp.qp_num);
	471	if (ipath_verbs_send(dev->dd, hwords, (u32 *) &qp->s_hdr,
	472	len, &ss))
	473	dev->n_no_piobuf++;
	474
	475	done:
	476	/* Queue the completion status entry. */
3859e39d	477	if (!(qp->s_flags & IPATH_S_SIGNAL_REQ_WR) \|\|
74ed6b5e BS	478	(wr->send_flags & IB_SEND_SIGNALED)) {
	479	wc.wr_id = wr->wr_id;
	480	wc.status = IB_WC_SUCCESS;
	481	wc.vendor_err = 0;
	482	wc.opcode = IB_WC_SEND;
	483	wc.byte_len = len;
062dbb69	484	wc.qp = &qp->ibqp;
74ed6b5e BS	485	wc.src_qp = 0;
	486	wc.wc_flags = 0;
	487	/* XXX initialize other fields? */
	488	ipath_cq_enter(to_icq(qp->ibqp.send_cq), &wc, 0);
	489	}
	490	kfree(sg_list);
	491
	492	ret = 0;
	493
	494	bail:
	495	return ret;
	496	}
	497
	498	/**
	499	* ipath_ud_rcv - receive an incoming UD packet
	500	* @dev: the device the packet came in on
	501	* @hdr: the packet header
	502	* @has_grh: true if the packet has a GRH
	503	* @data: the packet data
	504	* @tlen: the packet length
	505	* @qp: the QP the packet came on
	506	*
	507	* This is called from ipath_qp_rcv() to process an incoming UD packet
	508	* for the given QP.
	509	* Called at interrupt level.
	510	*/
	511	void ipath_ud_rcv(struct ipath_ibdev dev, struct ipath_ib_header hdr,
	512	int has_grh, void data, u32 tlen, struct ipath_qp qp)
	513	{
	514	struct ipath_other_headers *ohdr;
	515	int opcode;
	516	u32 hdrsize;
	517	u32 pad;
74ed6b5e BS	518	struct ib_wc wc;
	519	u32 qkey;
	520	u32 src_qp;
74ed6b5e BS	521	u16 dlid;
	522	int header_in_data;
	523
	524	/* Check for GRH */
	525	if (!has_grh) {
	526	ohdr = &hdr->u.oth;
	527	hdrsize = 8 + 12 + 8; /* LRH + BTH + DETH */
	528	qkey = be32_to_cpu(ohdr->u.ud.deth[0]);
	529	src_qp = be32_to_cpu(ohdr->u.ud.deth[1]);
	530	header_in_data = 0;
	531	} else {
	532	ohdr = &hdr->u.l.oth;
	533	hdrsize = 8 + 40 + 12 + 8; /* LRH + GRH + BTH + DETH */
	534	/*
	535	* The header with GRH is 68 bytes and the core driver sets
	536	* the eager header buffer size to 56 bytes so the last 12
	537	* bytes of the IB header is in the data buffer.
	538	*/
34b2aafe	539	header_in_data = dev->dd->ipath_rcvhdrentsize == 16;
74ed6b5e BS	540	if (header_in_data) {
	541	qkey = be32_to_cpu(((__be32 *) data)[1]);
	542	src_qp = be32_to_cpu(((__be32 *) data)[2]);
	543	data += 12;
	544	} else {
	545	qkey = be32_to_cpu(ohdr->u.ud.deth[0]);
	546	src_qp = be32_to_cpu(ohdr->u.ud.deth[1]);
	547	}
	548	}
27b678dd	549	src_qp &= IPATH_QPN_MASK;
74ed6b5e BS	550
	551	/*
	552	* Check that the permissive LID is only used on QP0
	553	* and the QKEY matches (see 9.6.1.4.1 and 9.6.1.5.1).
	554	*/
	555	if (qp->ibqp.qp_num) {
	556	if (unlikely(hdr->lrh[1] == IB_LID_PERMISSIVE \|\|
	557	hdr->lrh[3] == IB_LID_PERMISSIVE)) {
	558	dev->n_pkt_drops++;
	559	goto bail;
	560	}
	561	if (unlikely(qkey != qp->qkey)) {
	562	/* XXX OK to lose a count once in a while. */
	563	dev->qkey_violations++;
	564	dev->n_pkt_drops++;
	565	goto bail;
	566	}
	567	} else if (hdr->lrh[1] == IB_LID_PERMISSIVE \|\|
	568	hdr->lrh[3] == IB_LID_PERMISSIVE) {
	569	struct ib_smp smp = (struct ib_smp ) data;
	570
	571	if (smp->mgmt_class != IB_MGMT_CLASS_SUBN_DIRECTED_ROUTE) {
	572	dev->n_pkt_drops++;
	573	goto bail;
	574	}
	575	}
	576
	577	/* Get the number of bytes the message was padded by. */
	578	pad = (be32_to_cpu(ohdr->bth[0]) >> 20) & 3;
	579	if (unlikely(tlen < (hdrsize + pad + 4))) {
	580	/* Drop incomplete packets. */
	581	dev->n_pkt_drops++;
	582	goto bail;
	583	}
	584	tlen -= hdrsize + pad + 4;
	585
	586	/* Drop invalid MAD packets (see 13.5.3.1). */
	587	if (unlikely((qp->ibqp.qp_num == 0 &&
	588	(tlen != 256 \|\|
	589	(be16_to_cpu(hdr->lrh[0]) >> 12) != 15)) \|\|
	590	(qp->ibqp.qp_num == 1 &&
	591	(tlen != 256 \|\|
	592	(be16_to_cpu(hdr->lrh[0]) >> 12) == 15)))) {
	593	dev->n_pkt_drops++;
	594	goto bail;
	595	}
	596
	597	/*
	598	* A GRH is expected to preceed the data even if not
	599	* present on the wire.
	600	*/
	601	wc.byte_len = tlen + sizeof(struct ib_grh);
	602
	603	/*
	604	* The opcode is in the low byte when its in network order
	605	* (top byte when in host order).
	606	*/
	607	opcode = be32_to_cpu(ohdr->bth[0]) >> 24;
	608	if (qp->ibqp.qp_num > 1 &&
	609	opcode == IB_OPCODE_UD_SEND_ONLY_WITH_IMMEDIATE) {
	610	if (header_in_data) {
	611	wc.imm_data = (__be32 ) data;
	612	data += sizeof(__be32);
	613	} else
614	wc.imm_data = ohdr->u.ud.imm_data;
615	wc.wc_flags = IB_WC_WITH_IMM;
616	hdrsize += sizeof(u32);
617	} else if (opcode == IB_OPCODE_UD_SEND_ONLY) {
618	wc.imm_data = 0;
619	wc.wc_flags = 0;
620	} else {
621	dev->n_pkt_drops++;
622	goto bail;
623	}
624
625	/*
626	* Get the next work request entry to find where to put the data.
74ed6b5e	627	*/
373d9915 RC	628	if (qp->r_reuse_sge)
	629	qp->r_reuse_sge = 0;
	630	else if (!ipath_get_rwqe(qp, 0)) {
fba75200 BS	631	/*
	632	* Count VL15 packets dropped due to no receive buffer.
	633	* Otherwise, count them as buffer overruns since usually,
	634	* the HW will be able to receive packets even if there are
	635	* no QPs with posted receive buffers.
	636	*/
	637	if (qp->ibqp.qp_num == 0)
	638	dev->n_vl15_dropped++;
	639	else
	640	dev->rcv_errors++;
74ed6b5e BS	641	goto bail;
	642	}
	643	/* Silently drop packets which are too big. */
373d9915 RC	644	if (wc.byte_len > qp->r_len) {
373d9915 RC	645	qp->r_reuse_sge = 1;
74ed6b5e BS	646	dev->n_pkt_drops++;
	647	goto bail;
	648	}
74ed6b5e BS	649	if (has_grh) {
	650	ipath_copy_sge(&qp->r_sge, &hdr->u.l.grh,
	651	sizeof(struct ib_grh));
	652	wc.wc_flags \|= IB_WC_GRH;
	653	} else
	654	ipath_skip_sge(&qp->r_sge, sizeof(struct ib_grh));
	655	ipath_copy_sge(&qp->r_sge, data,
	656	wc.byte_len - sizeof(struct ib_grh));
041eab91	657	qp->r_wrid_valid = 0;
373d9915	658	wc.wr_id = qp->r_wr_id;
74ed6b5e BS	659	wc.status = IB_WC_SUCCESS;
	660	wc.opcode = IB_WC_RECV;
	661	wc.vendor_err = 0;
062dbb69	662	wc.qp = &qp->ibqp;
74ed6b5e BS	663	wc.src_qp = src_qp;
	664	/* XXX do we know which pkey matched? Only needed for GSI. */
	665	wc.pkey_index = 0;
	666	wc.slid = be16_to_cpu(hdr->lrh[3]);
	667	wc.sl = (be16_to_cpu(hdr->lrh[0]) >> 4) & 0xF;
	668	dlid = be16_to_cpu(hdr->lrh[1]);
	669	/*
	670	* Save the LMC lower bits if the destination LID is a unicast LID.
	671	*/
27b678dd	672	wc.dlid_path_bits = dlid >= IPATH_MULTICAST_LID_BASE ? 0 :
74ed6b5e BS	673	dlid & ((1 << (dev->mkeyprot_resv_lmc & 7)) - 1);
	674	/* Signal completion event if the solicited bit is set. */
	675	ipath_cq_enter(to_icq(qp->ibqp.recv_cq), &wc,
	676	(ohdr->bth[0] &
	677	__constant_cpu_to_be32(1 << 23)) != 0);
	678
	679	bail:;
	680	}