ipath_ud.c

来自「LINUX 2.6.17.4的源码」· C语言 代码 · 共 624 行 · 第 1/2 页

		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 =
			ipath_layer_get_guid(dev->dd);
		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 = IPS_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 = ipath_layer_get_lid(dev->dd);
	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 ? IPS_DEFAULT_P_KEY :
		ipath_layer_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 >= IPS_MULTICAST_LID_BASE &&
		ah_attr->dlid != IPS_PERMISSIVE_LID ?
		__constant_cpu_to_be32(IPS_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++ & IPS_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 (!test_bit(IPATH_S_SIGNAL_REQ_WR, &qp->s_flags) ||
	    (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_num = qp->ibqp.qp_num;
		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;
	unsigned long flags;
	struct ib_wc wc;
	u32 qkey;
	u32 src_qp;
	struct ipath_rq *rq;
	struct ipath_srq *srq;
	struct ipath_rwqe *wqe;
	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 =
			ipath_layer_get_rcvhdrentsize(dev->dd) == 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 &= IPS_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.
	 * 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);
		rq = &srq->rq;
	} else {
		srq = NULL;
		rq = &qp->r_rq;
	}
	spin_lock_irqsave(&rq->lock, flags);
	if (rq->tail == rq->head) {
		spin_unlock_irqrestore(&rq->lock, flags);
		dev->n_pkt_drops++;
		goto bail;
	}
	/* Silently drop packets which are too big. */
	wqe = get_rwqe_ptr(rq, rq->tail);
	if (wc.byte_len > wqe->length) {
		spin_unlock_irqrestore(&rq->lock, flags);
		dev->n_pkt_drops++;
		goto bail;
	}
	wc.wr_id = wqe->wr_id;
	qp->r_sge.sge = wqe->sg_list[0];
	qp->r_sge.sg_list = wqe->sg_list + 1;
	qp->r_sge.num_sge = wqe->num_sge;
	if (++rq->tail >= rq->size)
		rq->tail = 0;
	if (srq && srq->ibsrq.event_handler) {
		u32 n;

		if (rq->head < rq->tail)
			n = rq->size + rq->head - rq->tail;
		else
			n = rq->head - rq->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;
			srq->ibsrq.event_handler(&ev,
						 srq->ibsrq.srq_context);
		} else
			spin_unlock_irqrestore(&rq->lock, flags);
	} else
		spin_unlock_irqrestore(&rq->lock, flags);
	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));
	wc.status = IB_WC_SUCCESS;
	wc.opcode = IB_WC_RECV;
	wc.vendor_err = 0;
	wc.qp_num = qp->ibqp.qp_num;
	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 >= IPS_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:;
}