diff mbox

[v3,08/13] SoftiWarp Queue Pair methods

Message ID 20180114223603.19961-9-bmt@zurich.ibm.com (mailing list archive)
State RFC
Headers show

Commit Message

Bernard Metzler Jan. 14, 2018, 10:35 p.m. UTC
Signed-off-by: Bernard Metzler <bmt@zurich.ibm.com>
---
 drivers/infiniband/sw/siw/siw_qp.c | 1445 ++++++++++++++++++++++++++++++++++++
 1 file changed, 1445 insertions(+)
 create mode 100644 drivers/infiniband/sw/siw/siw_qp.c
diff mbox

Patch

diff --git a/drivers/infiniband/sw/siw/siw_qp.c b/drivers/infiniband/sw/siw/siw_qp.c
new file mode 100644
index 000000000000..a80647b55f4b
--- /dev/null
+++ b/drivers/infiniband/sw/siw/siw_qp.c
@@ -0,0 +1,1445 @@ 
+/*
+ * Software iWARP device driver
+ *
+ * Authors: Bernard Metzler <bmt@zurich.ibm.com>
+ *          Fredy Neeser <nfd@zurich.ibm.com>
+ *
+ * Copyright (c) 2008-2017, IBM Corporation
+ *
+ * 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
+ * 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.
+ *
+ *   - Neither the name of IBM nor the names of its contributors may be
+ *     used to endorse or promote products derived from this software without
+ *     specific prior written permission.
+ *
+ * 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 <linux/errno.h>
+#include <linux/types.h>
+#include <linux/net.h>
+#include <linux/file.h>
+#include <linux/scatterlist.h>
+#include <linux/highmem.h>
+#include <linux/vmalloc.h>
+#include <asm/barrier.h>
+#include <net/sock.h>
+#include <net/tcp_states.h>
+#include <net/tcp.h>
+
+#include <rdma/iw_cm.h>
+#include <rdma/ib_verbs.h>
+#include <rdma/ib_smi.h>
+#include <rdma/ib_user_verbs.h>
+
+#include "siw.h"
+#include "siw_obj.h"
+#include "siw_cm.h"
+
+static char siw_qp_state_to_string[SIW_QP_STATE_COUNT][sizeof "TERMINATE"] = {
+	[SIW_QP_STATE_IDLE]		= "IDLE",
+	[SIW_QP_STATE_RTR]		= "RTR",
+	[SIW_QP_STATE_RTS]		= "RTS",
+	[SIW_QP_STATE_CLOSING]		= "CLOSING",
+	[SIW_QP_STATE_TERMINATE]	= "TERMINATE",
+	[SIW_QP_STATE_ERROR]		= "ERROR"
+};
+
+/*
+ * iWARP (RDMAP, DDP and MPA) parameters as well as Softiwarp settings on a
+ * per-RDMAP message basis. Please keep order of initializer. All MPA len
+ * is initialized to minimum packet size.
+ */
+struct iwarp_msg_info iwarp_pktinfo[RDMAP_TERMINATE + 1] = { {
+	/* RDMAP_RDMA_WRITE */
+	.hdr_len = sizeof(struct iwarp_rdma_write),
+	.ctrl.mpa_len = htons(sizeof(struct iwarp_rdma_write) - 2),
+	.ctrl.ddp_rdmap_ctrl = DDP_FLAG_TAGGED | DDP_FLAG_LAST
+		| cpu_to_be16(DDP_VERSION << 8)
+		| cpu_to_be16(RDMAP_VERSION << 6)
+		| cpu_to_be16(RDMAP_RDMA_WRITE),
+	.proc_data = siw_proc_write
+},
+{	/* RDMAP_RDMA_READ_REQ */
+	.hdr_len = sizeof(struct iwarp_rdma_rreq),
+	.ctrl.mpa_len = htons(sizeof(struct iwarp_rdma_rreq) - 2),
+	.ctrl.ddp_rdmap_ctrl = DDP_FLAG_LAST
+		| cpu_to_be16(DDP_VERSION << 8)
+		| cpu_to_be16(RDMAP_VERSION << 6)
+		| cpu_to_be16(RDMAP_RDMA_READ_REQ),
+	.proc_data = siw_proc_rreq
+},
+{	/* RDMAP_RDMA_READ_RESP */
+	.hdr_len = sizeof(struct iwarp_rdma_rresp),
+	.ctrl.mpa_len = htons(sizeof(struct iwarp_rdma_rresp) - 2),
+	.ctrl.ddp_rdmap_ctrl = DDP_FLAG_TAGGED | DDP_FLAG_LAST
+		| cpu_to_be16(DDP_VERSION << 8)
+		| cpu_to_be16(RDMAP_VERSION << 6)
+		| cpu_to_be16(RDMAP_RDMA_READ_RESP),
+	.proc_data = siw_proc_rresp
+},
+{	/* RDMAP_SEND */
+	.hdr_len = sizeof(struct iwarp_send),
+	.ctrl.mpa_len = htons(sizeof(struct iwarp_send) - 2),
+	.ctrl.ddp_rdmap_ctrl = DDP_FLAG_LAST
+		| cpu_to_be16(DDP_VERSION << 8)
+		| cpu_to_be16(RDMAP_VERSION << 6)
+		| cpu_to_be16(RDMAP_SEND),
+	.proc_data = siw_proc_send
+},
+{	/* RDMAP_SEND_INVAL */
+	.hdr_len = sizeof(struct iwarp_send_inv),
+	.ctrl.mpa_len = htons(sizeof(struct iwarp_send_inv) - 2),
+	.ctrl.ddp_rdmap_ctrl = DDP_FLAG_LAST
+		| cpu_to_be16(DDP_VERSION << 8)
+		| cpu_to_be16(RDMAP_VERSION << 6)
+		| cpu_to_be16(RDMAP_SEND_INVAL),
+	.proc_data = siw_proc_send
+},
+{	/* RDMAP_SEND_SE */
+	.hdr_len = sizeof(struct iwarp_send),
+	.ctrl.mpa_len = htons(sizeof(struct iwarp_send) - 2),
+	.ctrl.ddp_rdmap_ctrl = DDP_FLAG_LAST
+		| cpu_to_be16(DDP_VERSION << 8)
+		| cpu_to_be16(RDMAP_VERSION << 6)
+		| cpu_to_be16(RDMAP_SEND_SE),
+	.proc_data = siw_proc_send
+},
+{	/* RDMAP_SEND_SE_INVAL */
+	.hdr_len = sizeof(struct iwarp_send_inv),
+	.ctrl.mpa_len = htons(sizeof(struct iwarp_send_inv) - 2),
+	.ctrl.ddp_rdmap_ctrl = DDP_FLAG_LAST
+		| cpu_to_be16(DDP_VERSION << 8)
+		| cpu_to_be16(RDMAP_VERSION << 6)
+		| cpu_to_be16(RDMAP_SEND_SE_INVAL),
+	.proc_data = siw_proc_send
+},
+{	/* RDMAP_TERMINATE */
+	.hdr_len = sizeof(struct iwarp_terminate),
+	.ctrl.mpa_len = htons(sizeof(struct iwarp_terminate) - 2),
+	.ctrl.ddp_rdmap_ctrl = DDP_FLAG_LAST
+		| cpu_to_be16(DDP_VERSION << 8)
+		| cpu_to_be16(RDMAP_VERSION << 6)
+		| cpu_to_be16(RDMAP_TERMINATE),
+	.proc_data = siw_proc_terminate
+} };
+
+void siw_qp_llp_data_ready(struct sock *sk)
+{
+	struct siw_qp		*qp;
+
+	read_lock(&sk->sk_callback_lock);
+
+	if (unlikely(!sk->sk_user_data || !sk_to_qp(sk)))
+		goto done;
+
+	qp = sk_to_qp(sk);
+
+	if (likely(!qp->rx_ctx.rx_suspend &&
+		   down_read_trylock(&qp->state_lock))) {
+		read_descriptor_t rd_desc = {.arg.data = qp, .count = 1};
+
+		if (likely(qp->attrs.state == SIW_QP_STATE_RTS))
+			/*
+			 * Implements data receive operation during
+			 * socket callback. TCP gracefully catches
+			 * the case where there is nothing to receive
+			 * (not calling siw_tcp_rx_data() then).
+			 */
+			tcp_read_sock(sk, &rd_desc, siw_tcp_rx_data);
+
+		up_read(&qp->state_lock);
+	} else {
+		siw_dbg_qp(qp, "unable to rx, suspend: %d\n",
+			   qp->rx_ctx.rx_suspend);
+	}
+done:
+	read_unlock(&sk->sk_callback_lock);
+}
+
+void siw_qp_llp_close(struct siw_qp *qp)
+{
+	siw_dbg_qp(qp, "enter llp close, state = %s\n",
+		   siw_qp_state_to_string[qp->attrs.state]);
+
+	down_write(&qp->state_lock);
+
+	qp->rx_ctx.rx_suspend = 1;
+	qp->tx_ctx.tx_suspend = 1;
+	qp->attrs.llp_stream_handle = NULL;
+
+	switch (qp->attrs.state) {
+
+	case SIW_QP_STATE_RTS:
+	case SIW_QP_STATE_RTR:
+	case SIW_QP_STATE_IDLE:
+	case SIW_QP_STATE_TERMINATE:
+
+		qp->attrs.state = SIW_QP_STATE_ERROR;
+
+		break;
+	/*
+	 * SIW_QP_STATE_CLOSING:
+	 *
+	 * This is a forced close. shall the QP be moved to
+	 * ERROR or IDLE ?
+	 */
+	case SIW_QP_STATE_CLOSING:
+		if (tx_wqe(qp)->wr_status == SIW_WR_IDLE)
+			qp->attrs.state = SIW_QP_STATE_ERROR;
+		else
+			qp->attrs.state = SIW_QP_STATE_IDLE;
+
+		break;
+
+	default:
+		siw_dbg_qp(qp, "llp close: no state transition needed: %s\n",
+			   siw_qp_state_to_string[qp->attrs.state]);
+		break;
+	}
+	siw_sq_flush(qp);
+	siw_rq_flush(qp);
+
+	/*
+	 * Dereference closing CEP
+	 */
+	if (qp->cep) {
+		siw_cep_put(qp->cep);
+		qp->cep = NULL;
+	}
+
+	up_write(&qp->state_lock);
+
+	siw_dbg_qp(qp, "llp close exit: state %s\n",
+		   siw_qp_state_to_string[qp->attrs.state]);
+}
+
+/*
+ * socket callback routine informing about newly available send space.
+ * Function schedules SQ work for processing SQ items.
+ */
+void siw_qp_llp_write_space(struct sock *sk)
+{
+	struct siw_cep	*cep = sk_to_cep(sk);
+
+	cep->sk_write_space(sk);
+
+	if (!test_bit(SOCK_NOSPACE, &sk->sk_socket->flags))
+		(void) siw_sq_start(cep->qp);
+}
+
+static int siw_qp_readq_init(struct siw_qp *qp, int irq_size, int orq_size)
+{
+	if (!irq_size)
+		irq_size = 1;
+	if (!orq_size)
+		orq_size = 1;
+
+	qp->attrs.irq_size = irq_size;
+	qp->attrs.orq_size = orq_size;
+
+	qp->irq = vzalloc(irq_size * sizeof(struct siw_sqe));
+	if (!qp->irq) {
+		siw_dbg_qp(qp, "irq malloc for %d failed\n", irq_size);
+		qp->attrs.irq_size = 0;
+		return -ENOMEM;
+	}
+	qp->orq = vzalloc(orq_size * sizeof(struct siw_sqe));
+	if (!qp->orq) {
+		siw_dbg_qp(qp, "orq malloc for %d failed\n", orq_size);
+		qp->attrs.orq_size = 0;
+		qp->attrs.irq_size = 0;
+		vfree(qp->irq);
+		return -ENOMEM;
+	}
+	return 0;
+}
+
+static int siw_qp_enable_crc(struct siw_qp *qp)
+{
+	struct siw_iwarp_rx *c_rx = &qp->rx_ctx;
+	struct siw_iwarp_tx *c_tx = &qp->tx_ctx;
+	int rv = 0;
+
+	if (siw_crypto_shash == NULL) {
+		rv = -ENOENT;
+		goto error;
+	}
+	c_tx->mpa_crc_hd = kzalloc(sizeof(struct shash_desc) +
+				   crypto_shash_descsize(siw_crypto_shash),
+				   GFP_KERNEL);
+	c_rx->mpa_crc_hd = kzalloc(sizeof(struct shash_desc) +
+				   crypto_shash_descsize(siw_crypto_shash),
+				   GFP_KERNEL);
+	if (!c_tx->mpa_crc_hd || !c_rx->mpa_crc_hd) {
+		rv = -ENOMEM;
+		goto error;
+	}
+	c_tx->mpa_crc_hd->tfm = siw_crypto_shash;
+	c_rx->mpa_crc_hd->tfm = siw_crypto_shash;
+
+	return 0;
+error:
+	siw_dbg_qp(qp, "falied loading crc32c. error %d\n", rv);
+
+	kfree(c_tx->mpa_crc_hd);
+	kfree(c_rx->mpa_crc_hd);
+
+	c_tx->mpa_crc_hd = c_rx->mpa_crc_hd = NULL;
+
+	return rv;
+}
+
+/*
+ * Send a non signalled READ or WRITE to peer side as negotiated
+ * with MPAv2 P2P setup protocol. The work request is only created
+ * as a current active WR and does not consume Send Queue space.
+ *
+ * Caller must hold QP state lock.
+ */
+int siw_qp_mpa_rts(struct siw_qp *qp, enum mpa_v2_ctrl ctrl)
+{
+	struct siw_wqe	*wqe = tx_wqe(qp);
+	unsigned long flags;
+	int rv = 0;
+
+	spin_lock_irqsave(&qp->sq_lock, flags);
+
+	if (unlikely(wqe->wr_status != SIW_WR_IDLE)) {
+		spin_unlock_irqrestore(&qp->sq_lock, flags);
+		return -EIO;
+	}
+	memset(wqe->mem, 0, sizeof(*wqe->mem) * SIW_MAX_SGE);
+
+	wqe->wr_status = SIW_WR_QUEUED;
+	wqe->sqe.flags = 0;
+	wqe->sqe.num_sge = 1;
+	wqe->sqe.sge[0].length = 0;
+	wqe->sqe.sge[0].laddr = 0;
+	wqe->sqe.sge[0].lkey = 0;
+	/*
+	 * While it must not be checked for inbound zero length
+	 * READ/WRITE, some HW may treat STag 0 special.
+	 */
+	wqe->sqe.rkey = 1;
+	wqe->sqe.raddr = 0;
+	wqe->processed = 0;
+
+	if (ctrl & MPA_V2_RDMA_WRITE_RTR)
+		wqe->sqe.opcode = SIW_OP_WRITE;
+	else if (ctrl & MPA_V2_RDMA_READ_RTR) {
+		struct siw_sqe	*rreq;
+
+		wqe->sqe.opcode = SIW_OP_READ;
+
+		spin_lock(&qp->orq_lock);
+
+		rreq = orq_get_free(qp);
+		if (rreq) {
+			siw_read_to_orq(rreq, &wqe->sqe);
+			qp->orq_put++;
+		} else
+			rv = -EIO;
+
+		spin_unlock(&qp->orq_lock);
+	} else
+		rv = -EINVAL;
+
+	if (rv)
+		wqe->wr_status = SIW_WR_IDLE;
+
+	spin_unlock_irqrestore(&qp->sq_lock, flags);
+
+	if (!rv)
+		rv = siw_sq_start(qp);
+
+	return rv;
+}
+
+/*
+ * Map memory access error to DDP tagged error
+ */
+enum ddp_ecode siw_tagged_error(enum siw_access_state state)
+{
+	if (state == E_STAG_INVALID)
+		return DDP_ECODE_T_INVALID_STAG;
+	if (state == E_BASE_BOUNDS)
+		return DDP_ECODE_T_BASE_BOUNDS;
+	if (state == E_PD_MISMATCH)
+		return DDP_ECODE_T_STAG_NOT_ASSOC;
+	if (state == E_ACCESS_PERM)
+		/*
+		 * RFC 5041 (DDP) lacks an ecode for insufficient access
+		 * permissions. 'Invalid STag' seem to be the closest
+		 * match though.
+		 */
+		return DDP_ECODE_T_INVALID_STAG;
+
+	WARN_ON(1);
+
+	return DDP_ECODE_T_INVALID_STAG;
+}
+
+/*
+ * Map memory access error to RDMAP protection error
+ */
+enum rdmap_ecode siw_rdmap_error(enum siw_access_state state)
+{
+	if (state == E_STAG_INVALID)
+		return RDMAP_ECODE_INVALID_STAG;
+	if (state == E_BASE_BOUNDS)
+		return RDMAP_ECODE_BASE_BOUNDS;
+	if (state == E_PD_MISMATCH)
+		return RDMAP_ECODE_STAG_NOT_ASSOC;
+	if (state == E_ACCESS_PERM)
+		return RDMAP_ECODE_ACCESS_RIGHTS;
+
+	return RDMAP_ECODE_UNSPECIFIED;
+}
+
+void siw_init_terminate(struct siw_qp *qp, enum term_elayer layer,
+			u8 etype, u8 ecode, int in_tx)
+{
+	if (!qp->term_info.valid) {
+		memset(&qp->term_info, 0, sizeof(qp->term_info));
+		qp->term_info.layer = layer;
+		qp->term_info.etype = etype;
+		qp->term_info.ecode = ecode;
+		qp->term_info.in_tx = in_tx;
+		qp->term_info.valid = 1;
+	}
+}
+
+/*
+ * Send a TERMINATE message, as defined in RFC's 5040/5041/5044/6581.
+ * Sending TERMINATE messages is best effort - such messages
+ * can only be send if the QP is still connected and it does
+ * not have another outbound message in-progress, i.e. the
+ * TERMINATE message must not interfer with an incomplete current
+ * transmit operation.
+ */
+void siw_send_terminate(struct siw_qp *qp)
+{
+	struct kvec		iov[3];
+	struct msghdr		msg = {.msg_flags = MSG_DONTWAIT|MSG_EOR};
+	struct iwarp_terminate	*term = NULL;
+	union iwarp_hdr		*err_hdr = NULL;
+	struct socket		*s = qp->attrs.llp_stream_handle;
+	struct siw_iwarp_rx	*rx_ctx = &qp->rx_ctx;
+	union iwarp_hdr		*rx_hdr = &rx_ctx->hdr;
+	u32 crc = 0;
+	int num_frags, len_terminate, rv;
+
+	if (!qp->term_info.valid)
+		return;
+
+	qp->term_info.valid = 0;
+
+	if (tx_wqe(qp)->wr_status == SIW_WR_INPROGRESS) {
+		siw_dbg_qp(qp, "cannot send TERMINATE: op %d in progress\n",
+			   tx_type(tx_wqe(qp)));
+		return;
+	}
+	if (!s && qp->cep)
+		/* QP not yet in RTS. Take socket from connection end point */
+		s = qp->cep->llp.sock;
+
+	if (!s) {
+		siw_dbg_qp(qp, "cannot send TERMINATE: not connected\n");
+		return;
+	}
+
+	term = kzalloc(sizeof(*term), GFP_KERNEL);
+	if (!term)
+		return;
+
+	term->ddp_qn = cpu_to_be32(RDMAP_UNTAGGED_QN_TERMINATE);
+	term->ddp_mo = 0;
+	term->ddp_msn = cpu_to_be32(1);
+
+	iov[0].iov_base = term;
+	iov[0].iov_len = sizeof(*term);
+
+	if ((qp->term_info.layer == TERM_ERROR_LAYER_DDP) ||
+	    ((qp->term_info.layer == TERM_ERROR_LAYER_RDMAP) &&
+	     (qp->term_info.etype != RDMAP_ETYPE_CATASTROPHIC))) {
+		err_hdr = kzalloc(sizeof(*err_hdr), GFP_KERNEL);
+		if (!err_hdr) {
+			kfree(term);
+			return;
+		}
+	}
+	memcpy(&term->ctrl, &iwarp_pktinfo[RDMAP_TERMINATE].ctrl,
+	       sizeof(struct iwarp_ctrl));
+
+	__rdmap_term_set_layer(term, qp->term_info.layer);
+	__rdmap_term_set_etype(term, qp->term_info.etype);
+	__rdmap_term_set_ecode(term, qp->term_info.ecode);
+
+	switch (qp->term_info.layer) {
+
+	case TERM_ERROR_LAYER_RDMAP:
+		if (qp->term_info.etype == RDMAP_ETYPE_CATASTROPHIC)
+			/* No additional DDP/RDMAP header to be included */
+			break;
+
+		if (qp->term_info.etype == RDMAP_ETYPE_REMOTE_PROTECTION) {
+			/*
+			 * Complete RDMAP frame will get attached, and
+			 * DDP segment length is valid
+			 */
+			term->flag_m = 1;
+			term->flag_d = 1;
+			term->flag_r = 1;
+
+			if (qp->term_info.in_tx) {
+				struct iwarp_rdma_rreq *rreq;
+				struct siw_wqe *wqe = tx_wqe(qp);
+
+				/* Inbound RREQ error, detected during
+				 * RRESP creation. Take state from
+				 * current TX work queue element to
+				 * reconstruct peers RREQ.
+				 */
+				rreq = (struct iwarp_rdma_rreq *)err_hdr;
+
+				memcpy(&rreq->ctrl,
+				       &iwarp_pktinfo[RDMAP_RDMA_READ_REQ].ctrl,
+				       sizeof(struct iwarp_ctrl));
+
+				rreq->rsvd = 0;
+				rreq->ddp_qn =
+					htonl(RDMAP_UNTAGGED_QN_RDMA_READ);
+
+				/* Provide RREQ's MSN as kept aside */
+				rreq->ddp_msn = htonl(wqe->sqe.sge[0].length);
+
+				rreq->ddp_mo = htonl(wqe->processed);
+				rreq->sink_stag = htonl(wqe->sqe.rkey);
+				rreq->sink_to = cpu_to_be64(wqe->sqe.raddr);
+				rreq->read_size = htonl(wqe->sqe.sge[0].length);
+				rreq->source_stag = htonl(wqe->sqe.sge[0].lkey);
+				rreq->source_to =
+					cpu_to_be64(wqe->sqe.sge[0].laddr);
+
+				iov[1].iov_base = rreq;
+				iov[1].iov_len = sizeof(*rreq);
+
+				rx_hdr = (union iwarp_hdr *)rreq;
+			} else {
+				/* Take RDMAP/DDP information from
+				 * current (failed) inbound frame.
+				 */
+				iov[1].iov_base = rx_hdr;
+
+				if (__rdmap_opcode(&rx_hdr->ctrl) ==
+				    RDMAP_RDMA_READ_REQ)
+					iov[1].iov_len =
+						sizeof(struct iwarp_rdma_rreq);
+				else /* SEND type */
+					iov[1].iov_len =
+						sizeof(struct iwarp_send);
+			}
+		} else {
+			/* Do not report DDP hdr information if packet
+			 * layout is unknown
+			 */
+			if ((qp->term_info.ecode == RDMAP_ECODE_VERSION) ||
+			    (qp->term_info.ecode == RDMAP_ECODE_OPCODE))
+				break;
+
+			iov[1].iov_base = rx_hdr;
+
+			/* Only DDP frame will get attached */
+			if (rx_hdr->ctrl.ddp_rdmap_ctrl & DDP_FLAG_TAGGED)
+				iov[1].iov_len =
+					sizeof(struct iwarp_rdma_write);
+			else
+				iov[1].iov_len = sizeof(struct iwarp_send);
+
+			term->flag_m = 1;
+			term->flag_d = 1;
+		}
+		term->ctrl.mpa_len = cpu_to_be16(iov[1].iov_len);
+
+		break;
+
+	case TERM_ERROR_LAYER_DDP:
+		/* Report error encountered while DDP processing.
+		 * This can only happen as a result of inbound
+		 * DDP processing
+		 */
+
+		/* Do not report DDP hdr information if packet
+		 * layout is unknown
+		 */
+		if (((qp->term_info.etype == DDP_ETYPE_TAGGED_BUF) &&
+		     (qp->term_info.ecode == DDP_ECODE_T_VERSION)) ||
+		    ((qp->term_info.etype == DDP_ETYPE_UNTAGGED_BUF) &&
+		     (qp->term_info.ecode == DDP_ECODE_UT_VERSION)))
+			break;
+
+		iov[1].iov_base = rx_hdr;
+
+		if (rx_hdr->ctrl.ddp_rdmap_ctrl & DDP_FLAG_TAGGED)
+			iov[1].iov_len = sizeof(struct iwarp_ctrl_tagged);
+		else
+			iov[1].iov_len = sizeof(struct iwarp_ctrl_untagged);
+
+		term->flag_m = 1;
+		term->flag_d = 1;
+
+		break;
+
+	default:
+		break;
+
+	}
+	if (term->flag_m || term->flag_d || term->flag_r) {
+		iov[2].iov_base = &crc;
+		iov[2].iov_len = sizeof(crc);
+		len_terminate = sizeof(*term) + iov[1].iov_len + MPA_CRC_SIZE;
+		num_frags = 3;
+	} else {
+		iov[1].iov_base = &crc;
+		iov[1].iov_len = sizeof(crc);
+		len_terminate = sizeof(*term) + MPA_CRC_SIZE;
+		num_frags = 2;
+	}
+
+	/* Adjust DDP Segment Length parameter, if valid */
+	if (term->flag_m) {
+		u32 real_ddp_len = be16_to_cpu(rx_hdr->ctrl.mpa_len);
+		enum rdma_opcode op = __rdmap_opcode(&rx_hdr->ctrl);
+
+		real_ddp_len -= iwarp_pktinfo[op].hdr_len - MPA_HDR_SIZE;
+		rx_hdr->ctrl.mpa_len = cpu_to_be16(real_ddp_len);
+	}
+
+	term->ctrl.mpa_len = cpu_to_be16(len_terminate -
+					 (MPA_HDR_SIZE + MPA_CRC_SIZE));
+	if (qp->tx_ctx.mpa_crc_hd) {
+		crypto_shash_init(rx_ctx->mpa_crc_hd);
+		if (siw_crc_array(rx_ctx->mpa_crc_hd, (u8 *)iov[0].iov_base,
+				  iov[0].iov_len))
+			goto out;
+
+		if (num_frags == 3) {
+			if (siw_crc_array(rx_ctx->mpa_crc_hd,
+					  (u8 *)iov[1].iov_base,
+					  iov[1].iov_len))
+				goto out;
+		}
+		crypto_shash_final(rx_ctx->mpa_crc_hd, (u8 *)&crc);
+	}
+
+	rv = kernel_sendmsg(s, &msg, iov, num_frags, len_terminate);
+	siw_dbg_qp(qp,
+		   "sent TERM: %s, layer %d, type %d, code %d (%d bytes)\n",
+		   rv == len_terminate ? "success" : "failure",
+		   __rdmap_term_layer(term), __rdmap_term_etype(term),
+		   __rdmap_term_ecode(term), rv);
+out:
+	kfree(term);
+	kfree(err_hdr);
+}
+
+/*
+ * handle all attrs other than state
+ */
+static void siw_qp_modify_nonstate(struct siw_qp *qp,
+				   struct siw_qp_attrs *attrs,
+				   enum siw_qp_attr_mask mask)
+{
+	if (mask & SIW_QP_ATTR_ACCESS_FLAGS) {
+		if (attrs->flags & SIW_RDMA_BIND_ENABLED)
+			qp->attrs.flags |= SIW_RDMA_BIND_ENABLED;
+		else
+			qp->attrs.flags &= ~SIW_RDMA_BIND_ENABLED;
+
+		if (attrs->flags & SIW_RDMA_WRITE_ENABLED)
+			qp->attrs.flags |= SIW_RDMA_WRITE_ENABLED;
+		else
+			qp->attrs.flags &= ~SIW_RDMA_WRITE_ENABLED;
+
+		if (attrs->flags & SIW_RDMA_READ_ENABLED)
+			qp->attrs.flags |= SIW_RDMA_READ_ENABLED;
+		else
+			qp->attrs.flags &= ~SIW_RDMA_READ_ENABLED;
+	}
+}
+
+/*
+ * caller holds qp->state_lock
+ */
+int siw_qp_modify(struct siw_qp *qp, struct siw_qp_attrs *attrs,
+		  enum siw_qp_attr_mask mask)
+{
+	int	drop_conn = 0, rv = 0;
+
+	if (!mask)
+		return 0;
+
+	siw_dbg_qp(qp, "state: %s => %s\n",
+		   siw_qp_state_to_string[qp->attrs.state],
+		   siw_qp_state_to_string[attrs->state]);
+
+	if (mask != SIW_QP_ATTR_STATE)
+		siw_qp_modify_nonstate(qp, attrs, mask);
+
+	if (!(mask & SIW_QP_ATTR_STATE))
+		return 0;
+
+	switch (qp->attrs.state) {
+
+	case SIW_QP_STATE_IDLE:
+	case SIW_QP_STATE_RTR:
+
+		switch (attrs->state) {
+
+		case SIW_QP_STATE_RTS:
+
+			if (attrs->flags & SIW_MPA_CRC) {
+				rv = siw_qp_enable_crc(qp);
+				if (rv)
+					break;
+			}
+			if (!(mask & SIW_QP_ATTR_LLP_HANDLE)) {
+				siw_dbg_qp(qp, "no socket\n");
+				rv = -EINVAL;
+				break;
+			}
+			if (!(mask & SIW_QP_ATTR_MPA)) {
+				siw_dbg_qp(qp, "no MPA\n");
+				rv = -EINVAL;
+				break;
+			}
+			siw_dbg_qp(qp, "enter rts, peer 0x%08x, loc 0x%08x\n",
+				   qp->cep->llp.raddr.sin_addr.s_addr,
+				   qp->cep->llp.laddr.sin_addr.s_addr);
+			/*
+			 * Initialize iWARP TX state
+			 */
+			qp->tx_ctx.ddp_msn[RDMAP_UNTAGGED_QN_SEND] = 0;
+			qp->tx_ctx.ddp_msn[RDMAP_UNTAGGED_QN_RDMA_READ] = 0;
+			qp->tx_ctx.ddp_msn[RDMAP_UNTAGGED_QN_TERMINATE] = 0;
+
+			/*
+			 * Initialize iWARP RX state
+			 */
+			qp->rx_ctx.ddp_msn[RDMAP_UNTAGGED_QN_SEND] = 1;
+			qp->rx_ctx.ddp_msn[RDMAP_UNTAGGED_QN_RDMA_READ] = 1;
+			qp->rx_ctx.ddp_msn[RDMAP_UNTAGGED_QN_TERMINATE] = 1;
+
+			/*
+			 * init IRD free queue, caller has already checked
+			 * limits.
+			 */
+			rv = siw_qp_readq_init(qp, attrs->irq_size,
+					       attrs->orq_size);
+			if (rv)
+				break;
+
+			qp->attrs.llp_stream_handle = attrs->llp_stream_handle;
+			qp->attrs.state = SIW_QP_STATE_RTS;
+
+			break;
+
+		case SIW_QP_STATE_ERROR:
+			siw_rq_flush(qp);
+			qp->attrs.state = SIW_QP_STATE_ERROR;
+			if (qp->cep) {
+				siw_cep_put(qp->cep);
+				qp->cep = NULL;
+			}
+			break;
+
+		case SIW_QP_STATE_RTR:
+			/* ignore */
+			break;
+
+		default:
+			siw_dbg_qp(qp, "state transition undefined: %s => %s\n",
+				   siw_qp_state_to_string[qp->attrs.state],
+				   siw_qp_state_to_string[attrs->state]);
+			break;
+		}
+		break;
+
+	case SIW_QP_STATE_RTS:
+
+		switch (attrs->state) {
+
+		case SIW_QP_STATE_CLOSING:
+			/*
+			 * Verbs: move to IDLE if SQ and ORQ are empty.
+			 * Move to ERROR otherwise. But first of all we must
+			 * close the connection. So we keep CLOSING or ERROR
+			 * as a transient state, schedule connection drop work
+			 * and wait for the socket state change upcall to
+			 * come back closed.
+			 */
+			if (tx_wqe(qp)->wr_status == SIW_WR_IDLE) {
+				qp->attrs.state = SIW_QP_STATE_CLOSING;
+			} else {
+				qp->attrs.state = SIW_QP_STATE_ERROR;
+				siw_sq_flush(qp);
+			}
+			siw_rq_flush(qp);
+
+			drop_conn = 1;
+			break;
+
+		case SIW_QP_STATE_TERMINATE:
+			qp->attrs.state = SIW_QP_STATE_TERMINATE;
+
+			siw_init_terminate(qp, TERM_ERROR_LAYER_RDMAP,
+					   RDMAP_ETYPE_CATASTROPHIC,
+					   RDMAP_ECODE_UNSPECIFIED, 1);
+			drop_conn = 1;
+
+			break;
+
+		case SIW_QP_STATE_ERROR:
+			/*
+			 * This is an emergency close.
+			 *
+			 * Any in progress transmit operation will get
+			 * cancelled.
+			 * This will likely result in a protocol failure,
+			 * if a TX operation is in transit. The caller
+			 * could unconditional wait to give the current
+			 * operation a chance to complete.
+			 * Esp., how to handle the non-empty IRQ case?
+			 * The peer was asking for data transfer at a valid
+			 * point in time.
+			 */
+			siw_sq_flush(qp);
+			siw_rq_flush(qp);
+			qp->attrs.state = SIW_QP_STATE_ERROR;
+			drop_conn = 1;
+
+			break;
+
+		default:
+			siw_dbg_qp(qp, "state transition undefined: %s => %s\n",
+				   siw_qp_state_to_string[qp->attrs.state],
+				   siw_qp_state_to_string[attrs->state]);
+			break;
+		}
+		break;
+
+	case SIW_QP_STATE_TERMINATE:
+
+		switch (attrs->state) {
+
+		case SIW_QP_STATE_ERROR:
+			siw_rq_flush(qp);
+			qp->attrs.state = SIW_QP_STATE_ERROR;
+
+			if (tx_wqe(qp)->wr_status != SIW_WR_IDLE)
+				siw_sq_flush(qp);
+
+			break;
+
+		default:
+			siw_dbg_qp(qp, "state transition undefined: %s => %s\n",
+				   siw_qp_state_to_string[qp->attrs.state],
+				   siw_qp_state_to_string[attrs->state]);
+		}
+		break;
+
+	case SIW_QP_STATE_CLOSING:
+
+		switch (attrs->state) {
+
+		case SIW_QP_STATE_IDLE:
+			WARN_ON(tx_wqe(qp)->wr_status != SIW_WR_IDLE);
+			qp->attrs.state = SIW_QP_STATE_IDLE;
+
+			break;
+
+		case SIW_QP_STATE_CLOSING:
+			/*
+			 * The LLP may already moved the QP to closing
+			 * due to graceful peer close init
+			 */
+			break;
+
+		case SIW_QP_STATE_ERROR:
+			/*
+			 * QP was moved to CLOSING by LLP event
+			 * not yet seen by user.
+			 */
+			qp->attrs.state = SIW_QP_STATE_ERROR;
+
+			if (tx_wqe(qp)->wr_status != SIW_WR_IDLE)
+				siw_sq_flush(qp);
+
+			siw_rq_flush(qp);
+
+			break;
+
+		default:
+			siw_dbg_qp(qp, "state transition undefined: %s => %s\n",
+				   siw_qp_state_to_string[qp->attrs.state],
+				   siw_qp_state_to_string[attrs->state]);
+
+			return -ECONNABORTED;
+		}
+		break;
+
+	default:
+		siw_dbg_qp(qp, " noop: state %s\n",
+			   siw_qp_state_to_string[qp->attrs.state]);
+		break;
+	}
+	if (drop_conn)
+		siw_qp_cm_drop(qp, 0);
+
+	return rv;
+}
+
+struct ib_qp *siw_get_base_qp(struct ib_device *base_dev, int id)
+{
+	struct siw_qp *qp =  siw_qp_id2obj(siw_dev_base2siw(base_dev), id);
+
+	if (qp) {
+		/*
+		 * siw_qp_id2obj() increments object reference count
+		 */
+		siw_qp_put(qp);
+		siw_dbg_qp(qp, "got base QP");
+
+		return &qp->base_qp;
+	}
+	return (struct ib_qp *)NULL;
+}
+
+/*
+ * siw_check_mem()
+ *
+ * Check protection domain, STAG state, access permissions and
+ * address range for memory object.
+ *
+ * @pd:		Protection Domain memory should belong to
+ * @mem:	memory to be checked
+ * @addr:	starting addr of mem
+ * @perms:	requested access permissions
+ * @len:	len of memory interval to be checked
+ *
+ */
+int siw_check_mem(struct siw_pd *pd, struct siw_mem *mem, u64 addr,
+		  enum siw_access_flags perms, int len)
+{
+	if (siw_mem2mr(mem)->pd != pd) {
+		siw_dbg(pd->hdr.sdev, "[PD %d]: pd mismatch\n", OBJ_ID(pd));
+		return -E_PD_MISMATCH;
+	}
+	if (!mem->stag_valid) {
+		siw_dbg(pd->hdr.sdev, "[PD %d]: stag 0x%08x invalid\n",
+			OBJ_ID(pd), OBJ_ID(mem));
+		return -E_STAG_INVALID;
+	}
+	/*
+	 * check access permissions
+	 */
+	if ((mem->perms & perms) < perms) {
+		siw_dbg(pd->hdr.sdev, "[PD %d]: permissions 0x%08x < 0x%08x\n",
+			OBJ_ID(pd), mem->perms, perms);
+		return -E_ACCESS_PERM;
+	}
+	/*
+	 * Check address interval: we relax check to allow memory shrinked
+	 * from the start address _after_ placing or fetching len bytes.
+	 * TODO: this relaxation is probably overdone
+	 */
+	if (addr < mem->va || addr + len > mem->va + mem->len) {
+		siw_dbg(pd->hdr.sdev, "[PD %d]: MEM interval len %d\n",
+			OBJ_ID(pd), len);
+		siw_dbg(pd->hdr.sdev, "[0x%016llx, 0x%016llx) out of bounds\n",
+			(unsigned long long)addr,
+			(unsigned long long)(addr + len));
+		siw_dbg(pd->hdr.sdev, "[0x%016llx, 0x%016llx] LKey=0x%08x\n",
+			(unsigned long long)mem->va,
+			(unsigned long long)(mem->va + mem->len),
+			OBJ_ID(mem));
+
+		return -E_BASE_BOUNDS;
+	}
+	return E_ACCESS_OK;
+}
+
+/*
+ * siw_check_sge()
+ *
+ * Check SGE for access rights in given interval
+ *
+ * @pd:		Protection Domain memory should belong to
+ * @sge:	SGE to be checked
+ * @mem:	array of memory references
+ * @perms:	requested access permissions
+ * @off:	starting offset in SGE
+ * @len:	len of memory interval to be checked
+ *
+ * NOTE: Function references SGE's memory object (mem->obj)
+ * if not yet done. New reference is kept if check went ok and
+ * released if check failed. If mem->obj is already valid, no new
+ * lookup is being done and mem is not released it check fails.
+ */
+int
+siw_check_sge(struct siw_pd *pd, struct siw_sge *sge,
+	      struct siw_mem *mem[], enum siw_access_flags perms,
+	      u32 off, int len)
+{
+	struct siw_device *sdev = pd->hdr.sdev;
+	int new_ref = 0, rv = E_ACCESS_OK;
+
+	if (len + off > sge->length) {
+		rv = -E_BASE_BOUNDS;
+		goto fail;
+	}
+	if (*mem == NULL) {
+		*mem = siw_mem_id2obj(sdev, sge->lkey >> 8);
+		if (*mem == NULL) {
+			rv = -E_STAG_INVALID;
+			goto fail;
+		}
+		new_ref = 1;
+	}
+
+	rv = siw_check_mem(pd, *mem, sge->laddr + off, perms, len);
+	if (rv)
+		goto fail;
+
+	return 0;
+
+fail:
+	if (new_ref) {
+		siw_mem_put(*mem);
+		*mem = NULL;
+	}
+	return rv;
+}
+
+void siw_read_to_orq(struct siw_sqe *rreq, struct siw_sqe *sqe)
+{
+	rreq->id = sqe->id;
+	rreq->opcode = sqe->opcode;
+	rreq->sge[0].laddr = sqe->sge[0].laddr;
+	rreq->sge[0].length = sqe->sge[0].length;
+	rreq->sge[0].lkey = sqe->sge[0].lkey;
+	rreq->sge[1].lkey = sqe->sge[1].lkey;
+	rreq->flags = sqe->flags | SIW_WQE_VALID;
+	rreq->num_sge = 1;
+}
+
+/*
+ * Must be called with SQ locked.
+ * To avoid complete SQ starvation by constant inbound READ requests,
+ * the active IRQ will not be served after qp->irq_burst, if the
+ * SQ has pending work.
+ */
+int siw_activate_tx(struct siw_qp *qp)
+{
+	struct siw_sqe	*irqe, *sqe;
+	struct siw_wqe	*wqe = tx_wqe(qp);
+	int rv = 1;
+
+	irqe = &qp->irq[qp->irq_get % qp->attrs.irq_size];
+
+	if (irqe->flags & SIW_WQE_VALID) {
+		sqe = sq_get_next(qp);
+		if (sqe && ++qp->irq_burst >= SIW_IRQ_MAXBURST_SQ_ACTIVE) {
+			qp->irq_burst = 0;
+			goto skip_irq;
+		}
+		memset(wqe->mem, 0, sizeof(*wqe->mem) * SIW_MAX_SGE);
+		wqe->wr_status = SIW_WR_QUEUED;
+
+		/* start READ RESPONSE */
+		wqe->sqe.opcode = SIW_OP_READ_RESPONSE;
+		wqe->sqe.flags = 0;
+		if (irqe->num_sge) {
+			wqe->sqe.num_sge = 1;
+			wqe->sqe.sge[0].length = irqe->sge[0].length;
+			wqe->sqe.sge[0].laddr = irqe->sge[0].laddr;
+			wqe->sqe.sge[0].lkey = irqe->sge[0].lkey;
+		} else {
+			wqe->sqe.num_sge = 0;
+		}
+
+		/* Retain original RREQ's message sequence number for
+		 * potential error reporting cases.
+		 */
+		wqe->sqe.sge[1].length = irqe->sge[1].length;
+
+		wqe->sqe.rkey = irqe->rkey;
+		wqe->sqe.raddr = irqe->raddr;
+
+		wqe->processed = 0;
+		qp->irq_get++;
+
+		/* mark current IRQ entry free */
+		smp_store_mb(irqe->flags, 0);
+
+		goto out;
+	}
+
+	sqe = sq_get_next(qp);
+	if (sqe) {
+skip_irq:
+		memset(wqe->mem, 0, sizeof(*wqe->mem) * SIW_MAX_SGE);
+		wqe->wr_status = SIW_WR_QUEUED;
+
+		/* First copy SQE to kernel private memory */
+		memcpy(&wqe->sqe, sqe, sizeof(*sqe));
+
+		if (wqe->sqe.opcode >= SIW_NUM_OPCODES) {
+			rv = -EINVAL;
+			goto out;
+		}
+		if (wqe->sqe.flags & SIW_WQE_INLINE) {
+			if (wqe->sqe.opcode != SIW_OP_SEND &&
+			    wqe->sqe.opcode != SIW_OP_WRITE) {
+				rv = -EINVAL;
+				goto out;
+			}
+			if (wqe->sqe.sge[0].length > SIW_MAX_INLINE) {
+				rv = -EINVAL;
+				goto out;
+			}
+			wqe->sqe.sge[0].laddr = (u64)&wqe->sqe.sge[1];
+			wqe->sqe.sge[0].lkey = 0;
+			wqe->sqe.num_sge = 1;
+		}
+		if (wqe->sqe.flags & SIW_WQE_READ_FENCE) {
+			/* A READ cannot be fenced */
+			if (unlikely(wqe->sqe.opcode == SIW_OP_READ ||
+			    wqe->sqe.opcode == SIW_OP_READ_LOCAL_INV)) {
+				siw_dbg_qp(qp, "cannot fence read\n");
+				rv = -EINVAL;
+				goto out;
+			}
+			spin_lock(&qp->orq_lock);
+
+			if (!siw_orq_empty(qp)) {
+				qp->tx_ctx.orq_fence = 1;
+				rv = 0;
+			}
+			spin_unlock(&qp->orq_lock);
+
+		} else if (wqe->sqe.opcode == SIW_OP_READ ||
+			   wqe->sqe.opcode == SIW_OP_READ_LOCAL_INV) {
+			struct siw_sqe	*rreq;
+
+			wqe->sqe.num_sge = 1;
+
+			spin_lock(&qp->orq_lock);
+
+			rreq = orq_get_free(qp);
+			if (rreq) {
+				/*
+				 * Make an immediate copy in ORQ to be ready
+				 * to process loopback READ reply
+				 */
+				siw_read_to_orq(rreq, &wqe->sqe);
+				qp->orq_put++;
+			} else {
+				qp->tx_ctx.orq_fence = 1;
+				rv = 0;
+			}
+			spin_unlock(&qp->orq_lock);
+		}
+
+		/* Clear SQE, can be re-used by application */
+		smp_store_mb(sqe->flags, 0);
+		qp->sq_get++;
+	} else {
+		rv = 0;
+	}
+out:
+	if (unlikely(rv < 0)) {
+		siw_dbg_qp(qp, "error %d\n", rv);
+		wqe->wr_status = SIW_WR_IDLE;
+	}
+	return rv;
+}
+
+static void siw_cq_notify(struct siw_cq *cq, u32 flags)
+{
+	u32 cq_notify;
+
+	if (unlikely(!cq->base_cq.comp_handler))
+		return;
+
+	cq_notify = READ_ONCE(*cq->notify);
+
+	if ((cq_notify & SIW_NOTIFY_NEXT_COMPLETION) ||
+	    ((cq_notify & SIW_NOTIFY_SOLICITED) &&
+	     (flags & SIW_WQE_SOLICITED))) {
+		/* de-arm CQ */
+		smp_store_mb(*cq->notify, SIW_NOTIFY_NOT);
+		(*cq->base_cq.comp_handler)(&cq->base_cq,
+					    cq->base_cq.cq_context);
+	}
+}
+
+int siw_sqe_complete(struct siw_qp *qp, struct siw_sqe *sqe, u32 bytes,
+		     enum siw_wc_status status)
+{
+	struct siw_cq *cq = qp->scq;
+	int rv = 0;
+
+	if (cq) {
+		u32 sqe_flags = sqe->flags;
+		struct siw_cqe *cqe;
+		u32 idx;
+		unsigned long flags;
+
+		spin_lock_irqsave(&cq->lock, flags);
+
+		idx = cq->cq_put % cq->num_cqe;
+		cqe = &cq->queue[idx];
+
+		if (!cqe->flags) {
+			cqe->id = sqe->id;
+			cqe->opcode = sqe->opcode;
+			cqe->status = status;
+			cqe->imm_data = 0;
+			cqe->bytes = bytes;
+
+			if (cq->kernel_verbs) {
+				siw_qp_get(qp);
+				cqe->qp = qp;
+			} else {
+				cqe->qp_id = QP_ID(qp);
+			}
+			/* mark CQE valid for application */
+			smp_store_mb(cqe->flags, SIW_WQE_VALID);
+			/* recycle SQE */
+			smp_store_mb(sqe->flags, 0);
+
+			cq->cq_put++;
+			spin_unlock_irqrestore(&cq->lock, flags);
+			siw_cq_notify(cq, sqe_flags);
+		} else {
+			spin_unlock_irqrestore(&cq->lock, flags);
+			rv = -ENOMEM;
+			siw_cq_event(cq, IB_EVENT_CQ_ERR);
+		}
+	} else {
+		/* recycle SQE */
+		smp_store_mb(sqe->flags, 0);
+	}
+	return rv;
+}
+
+int siw_rqe_complete(struct siw_qp *qp, struct siw_rqe *rqe, u32 bytes,
+		     enum siw_wc_status status)
+{
+	struct siw_cq *cq = qp->rcq;
+	int rv = 0;
+
+	if (cq) {
+		struct siw_cqe *cqe;
+		u32 idx;
+		unsigned long flags;
+
+		spin_lock_irqsave(&cq->lock, flags);
+
+		idx = cq->cq_put % cq->num_cqe;
+		cqe = &cq->queue[idx];
+
+		if (!cqe->flags) {
+			cqe->id = rqe->id;
+			cqe->opcode = SIW_OP_RECEIVE;
+			cqe->status = status;
+			cqe->imm_data = 0;
+			cqe->bytes = bytes;
+
+			if (cq->kernel_verbs) {
+				siw_qp_get(qp);
+				cqe->qp = qp;
+			} else
+				cqe->qp_id = QP_ID(qp);
+
+			/* mark CQE valid for application */
+			smp_store_mb(cqe->flags, SIW_WQE_VALID);
+			/* recycle RQE */
+			smp_store_mb(rqe->flags, 0);
+
+			cq->cq_put++;
+			spin_unlock_irqrestore(&cq->lock, flags);
+			siw_cq_notify(cq, SIW_WQE_SIGNALLED);
+		} else {
+			spin_unlock_irqrestore(&cq->lock, flags);
+			rv = -ENOMEM;
+			siw_cq_event(cq, IB_EVENT_CQ_ERR);
+		}
+	} else {
+		/* recycle RQE */
+		smp_store_mb(rqe->flags, 0);
+	}
+	return rv;
+}
+
+/*
+ * siw_sq_flush()
+ *
+ * Flush SQ and ORRQ entries to CQ.
+ *
+ * TODO: Add termination code for in-progress WQE.
+ * TODO: an in-progress WQE may have been partially
+ *       processed. It should be enforced, that transmission
+ *       of a started DDP segment must be completed if possible
+ *       by any chance.
+ *
+ * Must be called with QP state write lock held.
+ * Therefore, SQ and ORQ lock must not be taken.
+ */
+void siw_sq_flush(struct siw_qp *qp)
+{
+	struct siw_sqe	*sqe;
+	struct siw_wqe	*wqe = tx_wqe(qp);
+	int		async_event = 0;
+
+	siw_dbg_qp(qp, "enter\n");
+
+	/*
+	 * Start with completing any work currently on the ORQ
+	 */
+	for (;;) {
+		if (qp->attrs.orq_size == 0)
+			break;
+
+		sqe = &qp->orq[qp->orq_get % qp->attrs.orq_size];
+		if (!sqe->flags)
+			break;
+
+		if (siw_sqe_complete(qp, sqe, 0,
+				     SIW_WC_WR_FLUSH_ERR) != 0)
+			break;
+
+		qp->orq_get++;
+	}
+	/*
+	 * Flush an in-progess WQE if present
+	 */
+	if (wqe->wr_status != SIW_WR_IDLE) {
+		/*
+		 * TODO: Add iWARP Termination code
+		 */
+		siw_dbg_qp(qp, "flush current sqe, type %d, status %d\n",
+			   tx_type(wqe), wqe->wr_status);
+
+		siw_wqe_put_mem(wqe, tx_type(wqe));
+
+		if (tx_type(wqe) != SIW_OP_READ_RESPONSE &&
+			((tx_type(wqe) != SIW_OP_READ &&
+			  tx_type(wqe) != SIW_OP_READ_LOCAL_INV) ||
+			wqe->wr_status == SIW_WR_QUEUED))
+			/*
+			 * An in-progress Read Request is already in
+			 * the ORQ
+			 */
+			siw_sqe_complete(qp, &wqe->sqe, wqe->bytes,
+					 SIW_WC_WR_FLUSH_ERR);
+
+		wqe->wr_status = SIW_WR_IDLE;
+	}
+	/*
+	 * Flush the Send Queue
+	 */
+	while (qp->attrs.sq_size) {
+		sqe = &qp->sendq[qp->sq_get % qp->attrs.sq_size];
+		if (!sqe->flags)
+			break;
+
+		async_event = 1;
+		if (siw_sqe_complete(qp, sqe, 0, SIW_WC_WR_FLUSH_ERR) != 0)
+			/*
+			 * Shall IB_EVENT_SQ_DRAINED be supressed if work
+			 * completion fails?
+			 */
+			break;
+
+		sqe->flags = 0;
+		qp->sq_get++;
+	}
+	if (async_event)
+		siw_qp_event(qp, IB_EVENT_SQ_DRAINED);
+}
+
+/*
+ * siw_rq_flush()
+ *
+ * Flush recv queue entries to CQ.
+ *
+ * Must be called with QP state write lock held.
+ * Therefore, RQ lock must not be taken.
+ */
+void siw_rq_flush(struct siw_qp *qp)
+{
+	struct siw_wqe		*wqe = rx_wqe(qp);
+
+	siw_dbg_qp(qp, "enter\n");
+
+	/*
+	 * Flush an in-progess WQE if present
+	 */
+	if (wqe->wr_status != SIW_WR_IDLE) {
+		siw_dbg_qp(qp, "flush current rqe, type %d, status %d\n",
+			   rx_type(wqe), wqe->wr_status);
+
+		siw_wqe_put_mem(wqe, rx_type(wqe));
+
+		if (rx_type(wqe) == SIW_OP_RECEIVE) {
+			siw_rqe_complete(qp, &wqe->rqe, wqe->bytes,
+					 SIW_WC_WR_FLUSH_ERR);
+		} else if (rx_type(wqe) != SIW_OP_READ &&
+			   rx_type(wqe) != SIW_OP_READ_RESPONSE &&
+			   rx_type(wqe) != SIW_OP_WRITE) {
+			siw_sqe_complete(qp, &wqe->sqe, 0, SIW_WC_WR_FLUSH_ERR);
+		}
+		wqe->wr_status = SIW_WR_IDLE;
+	}
+	/*
+	 * Flush the Receive Queue
+	 */
+	while (qp->attrs.rq_size) {
+		struct siw_rqe *rqe =
+			&qp->recvq[qp->rq_get % qp->attrs.rq_size];
+
+		if (!rqe->flags)
+			break;
+
+		if (siw_rqe_complete(qp, rqe, 0, SIW_WC_WR_FLUSH_ERR) != 0)
+			break;
+
+		rqe->flags = 0;
+		qp->rq_get++;
+	}
+}