Add the rt linux 4.1.3-rt3 as base

Import the rt linux 4.1.3-rt3 as OPNFV kvm base.

It's from git://git.kernel.org/pub/scm/linux/kernel/git/rt/linux-rt-devel.git linux-4.1.y-rt and
the base is:

commit 0917f823c59692d751951bf5ea699a2d1e2f26a2
Author: Sebastian Andrzej Siewior <bigeasy@linutronix.de>
Date:   Sat Jul 25 12:13:34 2015 +0200

    Prepare v4.1.3-rt3

    Signed-off-by: Sebastian Andrzej Siewior <bigeasy@linutronix.de>

We lose all the git history this way and it's not good. We
should apply another opnfv project repo in future.

Change-Id: I87543d81c9df70d99c5001fbdf646b202c19f423
Signed-off-by: Yunhong Jiang <yunhong.jiang@intel.com>

1 files changed, 1376 insertions, 0 deletions

diff --git a/kernel/drivers/infiniband/hw/qib/qib_qp.c b/kernel/drivers/infiniband/hw/qib/qib_qp.c
new file mode 100644
index 000000000..4fa88ba29
--- /dev/null
+++ b/kernel/drivers/infiniband/hw/qib/qib_qp.c
@@ -0,0 +1,1376 @@
+/*
+ * Copyright (c) 2012, 2013 Intel Corporation.  All rights reserved.
+ * Copyright (c) 2006 - 2012 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 <linux/err.h>
+#include <linux/vmalloc.h>
+#include <linux/jhash.h>
+#ifdef CONFIG_DEBUG_FS
+#include <linux/seq_file.h>
+#endif
+
+#include "qib.h"
+
+#define BITS_PER_PAGE           (PAGE_SIZE*BITS_PER_BYTE)
+#define BITS_PER_PAGE_MASK      (BITS_PER_PAGE-1)
+
+static inline unsigned mk_qpn(struct qib_qpn_table *qpt,
+			      struct qpn_map *map, unsigned off)
+{
+	return (map - qpt->map) * BITS_PER_PAGE + off;
+}
+
+static inline unsigned find_next_offset(struct qib_qpn_table *qpt,
+					struct qpn_map *map, unsigned off,
+					unsigned n)
+{
+	if (qpt->mask) {
+		off++;
+		if (((off & qpt->mask) >> 1) >= n)
+			off = (off | qpt->mask) + 2;
+	} else
+		off = find_next_zero_bit(map->page, BITS_PER_PAGE, off);
+	return off;
+}
+
+/*
+ * Convert the AETH credit code into the number of credits.
+ */
+static u32 credit_table[31] = {
+	0,                      /* 0 */
+	1,                      /* 1 */
+	2,                      /* 2 */
+	3,                      /* 3 */
+	4,                      /* 4 */
+	6,                      /* 5 */
+	8,                      /* 6 */
+	12,                     /* 7 */
+	16,                     /* 8 */
+	24,                     /* 9 */
+	32,                     /* A */
+	48,                     /* B */
+	64,                     /* C */
+	96,                     /* D */
+	128,                    /* E */
+	192,                    /* F */
+	256,                    /* 10 */
+	384,                    /* 11 */
+	512,                    /* 12 */
+	768,                    /* 13 */
+	1024,                   /* 14 */
+	1536,                   /* 15 */
+	2048,                   /* 16 */
+	3072,                   /* 17 */
+	4096,                   /* 18 */
+	6144,                   /* 19 */
+	8192,                   /* 1A */
+	12288,                  /* 1B */
+	16384,                  /* 1C */
+	24576,                  /* 1D */
+	32768                   /* 1E */
+};
+
+static void get_map_page(struct qib_qpn_table *qpt, struct qpn_map *map)
+{
+	unsigned long page = get_zeroed_page(GFP_KERNEL);
+
+	/*
+	 * Free the page if someone raced with us installing it.
+	 */
+
+	spin_lock(&qpt->lock);
+	if (map->page)
+		free_page(page);
+	else
+		map->page = (void *)page;
+	spin_unlock(&qpt->lock);
+}
+
+/*
+ * Allocate the next available QPN or
+ * zero/one for QP type IB_QPT_SMI/IB_QPT_GSI.
+ */
+static int alloc_qpn(struct qib_devdata *dd, struct qib_qpn_table *qpt,
+		     enum ib_qp_type type, u8 port)
+{
+	u32 i, offset, max_scan, qpn;
+	struct qpn_map *map;
+	u32 ret;
+
+	if (type == IB_QPT_SMI || type == IB_QPT_GSI) {
+		unsigned n;
+
+		ret = type == IB_QPT_GSI;
+		n = 1 << (ret + 2 * (port - 1));
+		spin_lock(&qpt->lock);
+		if (qpt->flags & n)
+			ret = -EINVAL;
+		else
+			qpt->flags |= n;
+		spin_unlock(&qpt->lock);
+		goto bail;
+	}
+
+	qpn = qpt->last + 2;
+	if (qpn >= QPN_MAX)
+		qpn = 2;
+	if (qpt->mask && ((qpn & qpt->mask) >> 1) >= dd->n_krcv_queues)
+		qpn = (qpn | qpt->mask) + 2;
+	offset = qpn & BITS_PER_PAGE_MASK;
+	map = &qpt->map[qpn / BITS_PER_PAGE];
+	max_scan = qpt->nmaps - !offset;
+	for (i = 0;;) {
+		if (unlikely(!map->page)) {
+			get_map_page(qpt, map);
+			if (unlikely(!map->page))
+				break;
+		}
+		do {
+			if (!test_and_set_bit(offset, map->page)) {
+				qpt->last = qpn;
+				ret = qpn;
+				goto bail;
+			}
+			offset = find_next_offset(qpt, map, offset,
+				dd->n_krcv_queues);
+			qpn = mk_qpn(qpt, map, offset);
+			/*
+			 * This test differs from alloc_pidmap().
+			 * If find_next_offset() does find a zero
+			 * bit, we don't need to check for QPN
+			 * wrapping around past our starting QPN.
+			 * We just need to be sure we don't loop
+			 * forever.
+			 */
+		} while (offset < BITS_PER_PAGE && qpn < QPN_MAX);
+		/*
+		 * In order to keep the number of pages allocated to a
+		 * minimum, we scan the all existing pages before increasing
+		 * the size of the bitmap table.
+		 */
+		if (++i > max_scan) {
+			if (qpt->nmaps == QPNMAP_ENTRIES)
+				break;
+			map = &qpt->map[qpt->nmaps++];
+			offset = 0;
+		} else if (map < &qpt->map[qpt->nmaps]) {
+			++map;
+			offset = 0;
+		} else {
+			map = &qpt->map[0];
+			offset = 2;
+		}
+		qpn = mk_qpn(qpt, map, offset);
+	}
+
+	ret = -ENOMEM;
+
+bail:
+	return ret;
+}
+
+static void free_qpn(struct qib_qpn_table *qpt, u32 qpn)
+{
+	struct qpn_map *map;
+
+	map = qpt->map + qpn / BITS_PER_PAGE;
+	if (map->page)
+		clear_bit(qpn & BITS_PER_PAGE_MASK, map->page);
+}
+
+static inline unsigned qpn_hash(struct qib_ibdev *dev, u32 qpn)
+{
+	return jhash_1word(qpn, dev->qp_rnd) &
+		(dev->qp_table_size - 1);
+}
+
+
+/*
+ * Put the QP into the hash table.
+ * The hash table holds a reference to the QP.
+ */
+static void insert_qp(struct qib_ibdev *dev, struct qib_qp *qp)
+{
+	struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
+	unsigned long flags;
+	unsigned n = qpn_hash(dev, qp->ibqp.qp_num);
+
+	atomic_inc(&qp->refcount);
+	spin_lock_irqsave(&dev->qpt_lock, flags);
+
+	if (qp->ibqp.qp_num == 0)
+		rcu_assign_pointer(ibp->qp0, qp);
+	else if (qp->ibqp.qp_num == 1)
+		rcu_assign_pointer(ibp->qp1, qp);
+	else {
+		qp->next = dev->qp_table[n];
+		rcu_assign_pointer(dev->qp_table[n], qp);
+	}
+
+	spin_unlock_irqrestore(&dev->qpt_lock, flags);
+}
+
+/*
+ * Remove the QP from the table so it can't be found asynchronously by
+ * the receive interrupt routine.
+ */
+static void remove_qp(struct qib_ibdev *dev, struct qib_qp *qp)
+{
+	struct qib_ibport *ibp = to_iport(qp->ibqp.device, qp->port_num);
+	unsigned n = qpn_hash(dev, qp->ibqp.qp_num);
+	unsigned long flags;
+	int removed = 1;
+
+	spin_lock_irqsave(&dev->qpt_lock, flags);
+
+	if (rcu_dereference_protected(ibp->qp0,
+			lockdep_is_held(&dev->qpt_lock)) == qp) {
+		RCU_INIT_POINTER(ibp->qp0, NULL);
+	} else if (rcu_dereference_protected(ibp->qp1,
+			lockdep_is_held(&dev->qpt_lock)) == qp) {
+		RCU_INIT_POINTER(ibp->qp1, NULL);
+	} else {
+		struct qib_qp *q;
+		struct qib_qp __rcu **qpp;
+
+		removed = 0;
+		qpp = &dev->qp_table[n];
+		for (; (q = rcu_dereference_protected(*qpp,
+				lockdep_is_held(&dev->qpt_lock))) != NULL;
+				qpp = &q->next)
+			if (q == qp) {
+				RCU_INIT_POINTER(*qpp,
+					rcu_dereference_protected(qp->next,
+					 lockdep_is_held(&dev->qpt_lock)));
+				removed = 1;
+				break;
+			}
+	}
+
+	spin_unlock_irqrestore(&dev->qpt_lock, flags);
+	if (removed) {
+		synchronize_rcu();
+		atomic_dec(&qp->refcount);
+	}
+}
+
+/**
+ * qib_free_all_qps - check for QPs still in use
+ * @qpt: the QP table to empty
+ *
+ * There should not be any QPs still in use.
+ * Free memory for table.
+ */
+unsigned qib_free_all_qps(struct qib_devdata *dd)
+{
+	struct qib_ibdev *dev = &dd->verbs_dev;
+	unsigned long flags;
+	struct qib_qp *qp;
+	unsigned n, qp_inuse = 0;
+
+	for (n = 0; n < dd->num_pports; n++) {
+		struct qib_ibport *ibp = &dd->pport[n].ibport_data;
+
+		if (!qib_mcast_tree_empty(ibp))
+			qp_inuse++;
+		rcu_read_lock();
+		if (rcu_dereference(ibp->qp0))
+			qp_inuse++;
+		if (rcu_dereference(ibp->qp1))
+			qp_inuse++;
+		rcu_read_unlock();
+	}
+
+	spin_lock_irqsave(&dev->qpt_lock, flags);
+	for (n = 0; n < dev->qp_table_size; n++) {
+		qp = rcu_dereference_protected(dev->qp_table[n],
+			lockdep_is_held(&dev->qpt_lock));
+		RCU_INIT_POINTER(dev->qp_table[n], NULL);
+
+		for (; qp; qp = rcu_dereference_protected(qp->next,
+					lockdep_is_held(&dev->qpt_lock)))
+			qp_inuse++;
+	}
+	spin_unlock_irqrestore(&dev->qpt_lock, flags);
+	synchronize_rcu();
+
+	return qp_inuse;
+}
+
+/**
+ * qib_lookup_qpn - return the QP with the given QPN
+ * @qpt: the QP table
+ * @qpn: the QP number to look up
+ *
+ * The caller is responsible for decrementing the QP reference count
+ * when done.
+ */
+struct qib_qp *qib_lookup_qpn(struct qib_ibport *ibp, u32 qpn)
+{
+	struct qib_qp *qp = NULL;
+
+	rcu_read_lock();
+	if (unlikely(qpn <= 1)) {
+		if (qpn == 0)
+			qp = rcu_dereference(ibp->qp0);
+		else
+			qp = rcu_dereference(ibp->qp1);
+		if (qp)
+			atomic_inc(&qp->refcount);
+	} else {
+		struct qib_ibdev *dev = &ppd_from_ibp(ibp)->dd->verbs_dev;
+		unsigned n = qpn_hash(dev, qpn);
+
+		for (qp = rcu_dereference(dev->qp_table[n]); qp;
+			qp = rcu_dereference(qp->next))
+			if (qp->ibqp.qp_num == qpn) {
+				atomic_inc(&qp->refcount);
+				break;
+			}
+	}
+	rcu_read_unlock();
+	return qp;
+}
+
+/**
+ * qib_reset_qp - initialize the QP state to the reset state
+ * @qp: the QP to reset
+ * @type: the QP type
+ */
+static void qib_reset_qp(struct qib_qp *qp, enum ib_qp_type type)
+{
+	qp->remote_qpn = 0;
+	qp->qkey = 0;
+	qp->qp_access_flags = 0;
+	atomic_set(&qp->s_dma_busy, 0);
+	qp->s_flags &= QIB_S_SIGNAL_REQ_WR;
+	qp->s_hdrwords = 0;
+	qp->s_wqe = NULL;
+	qp->s_draining = 0;
+	qp->s_next_psn = 0;
+	qp->s_last_psn = 0;
+	qp->s_sending_psn = 0;
+	qp->s_sending_hpsn = 0;
+	qp->s_psn = 0;
+	qp->r_psn = 0;
+	qp->r_msn = 0;
+	if (type == IB_QPT_RC) {
+		qp->s_state = IB_OPCODE_RC_SEND_LAST;
+		qp->r_state = IB_OPCODE_RC_SEND_LAST;
+	} else {
+		qp->s_state = IB_OPCODE_UC_SEND_LAST;
+		qp->r_state = IB_OPCODE_UC_SEND_LAST;
+	}
+	qp->s_ack_state = IB_OPCODE_RC_ACKNOWLEDGE;
+	qp->r_nak_state = 0;
+	qp->r_aflags = 0;
+	qp->r_flags = 0;
+	qp->s_head = 0;
+	qp->s_tail = 0;
+	qp->s_cur = 0;
+	qp->s_acked = 0;
+	qp->s_last = 0;
+	qp->s_ssn = 1;
+	qp->s_lsn = 0;
+	qp->s_mig_state = IB_MIG_MIGRATED;
+	memset(qp->s_ack_queue, 0, sizeof(qp->s_ack_queue));
+	qp->r_head_ack_queue = 0;
+	qp->s_tail_ack_queue = 0;
+	qp->s_num_rd_atomic = 0;
+	if (qp->r_rq.wq) {
+		qp->r_rq.wq->head = 0;
+		qp->r_rq.wq->tail = 0;
+	}
+	qp->r_sge.num_sge = 0;
+}
+
+static void clear_mr_refs(struct qib_qp *qp, int clr_sends)
+{
+	unsigned n;
+
+	if (test_and_clear_bit(QIB_R_REWIND_SGE, &qp->r_aflags))
+		qib_put_ss(&qp->s_rdma_read_sge);
+
+	qib_put_ss(&qp->r_sge);
+
+	if (clr_sends) {
+		while (qp->s_last != qp->s_head) {
+			struct qib_swqe *wqe = get_swqe_ptr(qp, qp->s_last);
+			unsigned i;
+
+			for (i = 0; i < wqe->wr.num_sge; i++) {
+				struct qib_sge *sge = &wqe->sg_list[i];
+
+				qib_put_mr(sge->mr);
+			}
+			if (qp->ibqp.qp_type == IB_QPT_UD ||
+			    qp->ibqp.qp_type == IB_QPT_SMI ||
+			    qp->ibqp.qp_type == IB_QPT_GSI)
+				atomic_dec(&to_iah(wqe->wr.wr.ud.ah)->refcount);
+			if (++qp->s_last >= qp->s_size)
+				qp->s_last = 0;
+		}
+		if (qp->s_rdma_mr) {
+			qib_put_mr(qp->s_rdma_mr);
+			qp->s_rdma_mr = NULL;
+		}
+	}
+
+	if (qp->ibqp.qp_type != IB_QPT_RC)
+		return;
+
+	for (n = 0; n < ARRAY_SIZE(qp->s_ack_queue); n++) {
+		struct qib_ack_entry *e = &qp->s_ack_queue[n];
+
+		if (e->opcode == IB_OPCODE_RC_RDMA_READ_REQUEST &&
+		    e->rdma_sge.mr) {
+			qib_put_mr(e->rdma_sge.mr);
+			e->rdma_sge.mr = NULL;
+		}
+	}
+}
+
+/**
+ * qib_error_qp - put a QP into the error state
+ * @qp: the QP to put into the error state
+ * @err: the receive completion error to signal if a RWQE is active
+ *
+ * Flushes both send and receive work queues.
+ * Returns true if last WQE event should be generated.
+ * The QP r_lock and s_lock should be held and interrupts disabled.
+ * If we are already in error state, just return.
+ */
+int qib_error_qp(struct qib_qp *qp, enum ib_wc_status err)
+{
+	struct qib_ibdev *dev = to_idev(qp->ibqp.device);
+	struct ib_wc wc;
+	int ret = 0;
+
+	if (qp->state == IB_QPS_ERR || qp->state == IB_QPS_RESET)
+		goto bail;
+
+	qp->state = IB_QPS_ERR;
+
+	if (qp->s_flags & (QIB_S_TIMER | QIB_S_WAIT_RNR)) {
+		qp->s_flags &= ~(QIB_S_TIMER | QIB_S_WAIT_RNR);
+		del_timer(&qp->s_timer);
+	}
+
+	if (qp->s_flags & QIB_S_ANY_WAIT_SEND)
+		qp->s_flags &= ~QIB_S_ANY_WAIT_SEND;
+
+	spin_lock(&dev->pending_lock);
+	if (!list_empty(&qp->iowait) && !(qp->s_flags & QIB_S_BUSY)) {
+		qp->s_flags &= ~QIB_S_ANY_WAIT_IO;
+		list_del_init(&qp->iowait);
+	}
+	spin_unlock(&dev->pending_lock);
+
+	if (!(qp->s_flags & QIB_S_BUSY)) {
+		qp->s_hdrwords = 0;
+		if (qp->s_rdma_mr) {
+			qib_put_mr(qp->s_rdma_mr);
+			qp->s_rdma_mr = NULL;
+		}
+		if (qp->s_tx) {
+			qib_put_txreq(qp->s_tx);
+			qp->s_tx = NULL;
+		}
+	}
+
+	/* Schedule the sending tasklet to drain the send work queue. */
+	if (qp->s_last != qp->s_head)
+		qib_schedule_send(qp);
+
+	clear_mr_refs(qp, 0);
+
+	memset(&wc, 0, sizeof(wc));
+	wc.qp = &qp->ibqp;
+	wc.opcode = IB_WC_RECV;
+
+	if (test_and_clear_bit(QIB_R_WRID_VALID, &qp->r_aflags)) {
+		wc.wr_id = qp->r_wr_id;
+		wc.status = err;
+		qib_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
+	}
+	wc.status = IB_WC_WR_FLUSH_ERR;
+
+	if (qp->r_rq.wq) {
+		struct qib_rwq *wq;
+		u32 head;
+		u32 tail;
+
+		spin_lock(&qp->r_rq.lock);
+
+		/* sanity check pointers before trusting them */
+		wq = qp->r_rq.wq;
+		head = wq->head;
+		if (head >= qp->r_rq.size)
+			head = 0;
+		tail = wq->tail;
+		if (tail >= qp->r_rq.size)
+			tail = 0;
+		while (tail != head) {
+			wc.wr_id = get_rwqe_ptr(&qp->r_rq, tail)->wr_id;
+			if (++tail >= qp->r_rq.size)
+				tail = 0;
+			qib_cq_enter(to_icq(qp->ibqp.recv_cq), &wc, 1);
+		}
+		wq->tail = tail;
+
+		spin_unlock(&qp->r_rq.lock);
+	} else if (qp->ibqp.event_handler)
+		ret = 1;
+
+bail:
+	return ret;
+}
+
+/**
+ * qib_modify_qp - modify the attributes of a queue pair
+ * @ibqp: the queue pair who's attributes we're modifying
+ * @attr: the new attributes
+ * @attr_mask: the mask of attributes to modify
+ * @udata: user data for libibverbs.so
+ *
+ * Returns 0 on success, otherwise returns an errno.
+ */
+int qib_modify_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
+		  int attr_mask, struct ib_udata *udata)
+{
+	struct qib_ibdev *dev = to_idev(ibqp->device);
+	struct qib_qp *qp = to_iqp(ibqp);
+	enum ib_qp_state cur_state, new_state;
+	struct ib_event ev;
+	int lastwqe = 0;
+	int mig = 0;
+	int ret;
+	u32 pmtu = 0; /* for gcc warning only */
+
+	spin_lock_irq(&qp->r_lock);
+	spin_lock(&qp->s_lock);
+
+	cur_state = attr_mask & IB_QP_CUR_STATE ?
+		attr->cur_qp_state : qp->state;
+	new_state = attr_mask & IB_QP_STATE ? attr->qp_state : cur_state;
+
+	if (!ib_modify_qp_is_ok(cur_state, new_state, ibqp->qp_type,
+				attr_mask, IB_LINK_LAYER_UNSPECIFIED))
+		goto inval;
+
+	if (attr_mask & IB_QP_AV) {
+		if (attr->ah_attr.dlid >= QIB_MULTICAST_LID_BASE)
+			goto inval;
+		if (qib_check_ah(qp->ibqp.device, &attr->ah_attr))
+			goto inval;
+	}
+
+	if (attr_mask & IB_QP_ALT_PATH) {
+		if (attr->alt_ah_attr.dlid >= QIB_MULTICAST_LID_BASE)
+			goto inval;
+		if (qib_check_ah(qp->ibqp.device, &attr->alt_ah_attr))
+			goto inval;
+		if (attr->alt_pkey_index >= qib_get_npkeys(dd_from_dev(dev)))
+			goto inval;
+	}
+
+	if (attr_mask & IB_QP_PKEY_INDEX)
+		if (attr->pkey_index >= qib_get_npkeys(dd_from_dev(dev)))
+			goto inval;
+
+	if (attr_mask & IB_QP_MIN_RNR_TIMER)
+		if (attr->min_rnr_timer > 31)
+			goto inval;
+
+	if (attr_mask & IB_QP_PORT)
+		if (qp->ibqp.qp_type == IB_QPT_SMI ||
+		    qp->ibqp.qp_type == IB_QPT_GSI ||
+		    attr->port_num == 0 ||
+		    attr->port_num > ibqp->device->phys_port_cnt)
+			goto inval;
+
+	if (attr_mask & IB_QP_DEST_QPN)
+		if (attr->dest_qp_num > QIB_QPN_MASK)
+			goto inval;
+
+	if (attr_mask & IB_QP_RETRY_CNT)
+		if (attr->retry_cnt > 7)
+			goto inval;
+
+	if (attr_mask & IB_QP_RNR_RETRY)
+		if (attr->rnr_retry > 7)
+			goto inval;
+
+	/*
+	 * Don't allow invalid path_mtu values.  OK to set greater
+	 * than the active mtu (or even the max_cap, if we have tuned
+	 * that to a small mtu.  We'll set qp->path_mtu
+	 * to the lesser of requested attribute mtu and active,
+	 * for packetizing messages.
+	 * Note that the QP port has to be set in INIT and MTU in RTR.
+	 */
+	if (attr_mask & IB_QP_PATH_MTU) {
+		struct qib_devdata *dd = dd_from_dev(dev);
+		int mtu, pidx = qp->port_num - 1;
+
+		mtu = ib_mtu_enum_to_int(attr->path_mtu);
+		if (mtu == -1)
+			goto inval;
+		if (mtu > dd->pport[pidx].ibmtu) {
+			switch (dd->pport[pidx].ibmtu) {
+			case 4096:
+				pmtu = IB_MTU_4096;
+				break;
+			case 2048:
+				pmtu = IB_MTU_2048;
+				break;
+			case 1024:
+				pmtu = IB_MTU_1024;
+				break;
+			case 512:
+				pmtu = IB_MTU_512;
+				break;
+			case 256:
+				pmtu = IB_MTU_256;
+				break;
+			default:
+				pmtu = IB_MTU_2048;
+			}
+		} else
+			pmtu = attr->path_mtu;
+	}
+
+	if (attr_mask & IB_QP_PATH_MIG_STATE) {
+		if (attr->path_mig_state == IB_MIG_REARM) {
+			if (qp->s_mig_state == IB_MIG_ARMED)
+				goto inval;
+			if (new_state != IB_QPS_RTS)
+				goto inval;
+		} else if (attr->path_mig_state == IB_MIG_MIGRATED) {
+			if (qp->s_mig_state == IB_MIG_REARM)
+				goto inval;
+			if (new_state != IB_QPS_RTS && new_state != IB_QPS_SQD)
+				goto inval;
+			if (qp->s_mig_state == IB_MIG_ARMED)
+				mig = 1;
+		} else
+			goto inval;
+	}
+
+	if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
+		if (attr->max_dest_rd_atomic > QIB_MAX_RDMA_ATOMIC)
+			goto inval;
+
+	switch (new_state) {
+	case IB_QPS_RESET:
+		if (qp->state != IB_QPS_RESET) {
+			qp->state = IB_QPS_RESET;
+			spin_lock(&dev->pending_lock);
+			if (!list_empty(&qp->iowait))
+				list_del_init(&qp->iowait);
+			spin_unlock(&dev->pending_lock);
+			qp->s_flags &= ~(QIB_S_TIMER | QIB_S_ANY_WAIT);
+			spin_unlock(&qp->s_lock);
+			spin_unlock_irq(&qp->r_lock);
+			/* Stop the sending work queue and retry timer */
+			cancel_work_sync(&qp->s_work);
+			del_timer_sync(&qp->s_timer);
+			wait_event(qp->wait_dma, !atomic_read(&qp->s_dma_busy));
+			if (qp->s_tx) {
+				qib_put_txreq(qp->s_tx);
+				qp->s_tx = NULL;
+			}
+			remove_qp(dev, qp);
+			wait_event(qp->wait, !atomic_read(&qp->refcount));
+			spin_lock_irq(&qp->r_lock);
+			spin_lock(&qp->s_lock);
+			clear_mr_refs(qp, 1);
+			qib_reset_qp(qp, ibqp->qp_type);
+		}
+		break;
+
+	case IB_QPS_RTR:
+		/* Allow event to retrigger if QP set to RTR more than once */
+		qp->r_flags &= ~QIB_R_COMM_EST;
+		qp->state = new_state;
+		break;
+
+	case IB_QPS_SQD:
+		qp->s_draining = qp->s_last != qp->s_cur;
+		qp->state = new_state;
+		break;
+
+	case IB_QPS_SQE:
+		if (qp->ibqp.qp_type == IB_QPT_RC)
+			goto inval;
+		qp->state = new_state;
+		break;
+
+	case IB_QPS_ERR:
+		lastwqe = qib_error_qp(qp, IB_WC_WR_FLUSH_ERR);
+		break;
+
+	default:
+		qp->state = new_state;
+		break;
+	}
+
+	if (attr_mask & IB_QP_PKEY_INDEX)
+		qp->s_pkey_index = attr->pkey_index;
+
+	if (attr_mask & IB_QP_PORT)
+		qp->port_num = attr->port_num;
+
+	if (attr_mask & IB_QP_DEST_QPN)
+		qp->remote_qpn = attr->dest_qp_num;
+
+	if (attr_mask & IB_QP_SQ_PSN) {
+		qp->s_next_psn = attr->sq_psn & QIB_PSN_MASK;
+		qp->s_psn = qp->s_next_psn;
+		qp->s_sending_psn = qp->s_next_psn;
+		qp->s_last_psn = qp->s_next_psn - 1;
+		qp->s_sending_hpsn = qp->s_last_psn;
+	}
+
+	if (attr_mask & IB_QP_RQ_PSN)
+		qp->r_psn = attr->rq_psn & QIB_PSN_MASK;
+
+	if (attr_mask & IB_QP_ACCESS_FLAGS)
+		qp->qp_access_flags = attr->qp_access_flags;
+
+	if (attr_mask & IB_QP_AV) {
+		qp->remote_ah_attr = attr->ah_attr;
+		qp->s_srate = attr->ah_attr.static_rate;
+	}
+
+	if (attr_mask & IB_QP_ALT_PATH) {
+		qp->alt_ah_attr = attr->alt_ah_attr;
+		qp->s_alt_pkey_index = attr->alt_pkey_index;
+	}
+
+	if (attr_mask & IB_QP_PATH_MIG_STATE) {
+		qp->s_mig_state = attr->path_mig_state;
+		if (mig) {
+			qp->remote_ah_attr = qp->alt_ah_attr;
+			qp->port_num = qp->alt_ah_attr.port_num;
+			qp->s_pkey_index = qp->s_alt_pkey_index;
+		}
+	}
+
+	if (attr_mask & IB_QP_PATH_MTU) {
+		qp->path_mtu = pmtu;
+		qp->pmtu = ib_mtu_enum_to_int(pmtu);
+	}
+
+	if (attr_mask & IB_QP_RETRY_CNT) {
+		qp->s_retry_cnt = attr->retry_cnt;
+		qp->s_retry = attr->retry_cnt;
+	}
+
+	if (attr_mask & IB_QP_RNR_RETRY) {
+		qp->s_rnr_retry_cnt = attr->rnr_retry;
+		qp->s_rnr_retry = attr->rnr_retry;
+	}
+
+	if (attr_mask & IB_QP_MIN_RNR_TIMER)
+		qp->r_min_rnr_timer = attr->min_rnr_timer;
+
+	if (attr_mask & IB_QP_TIMEOUT) {
+		qp->timeout = attr->timeout;
+		qp->timeout_jiffies =
+			usecs_to_jiffies((4096UL * (1UL << qp->timeout)) /
+				1000UL);
+	}
+
+	if (attr_mask & IB_QP_QKEY)
+		qp->qkey = attr->qkey;
+
+	if (attr_mask & IB_QP_MAX_DEST_RD_ATOMIC)
+		qp->r_max_rd_atomic = attr->max_dest_rd_atomic;
+
+	if (attr_mask & IB_QP_MAX_QP_RD_ATOMIC)
+		qp->s_max_rd_atomic = attr->max_rd_atomic;
+
+	spin_unlock(&qp->s_lock);
+	spin_unlock_irq(&qp->r_lock);
+
+	if (cur_state == IB_QPS_RESET && new_state == IB_QPS_INIT)
+		insert_qp(dev, qp);
+
+	if (lastwqe) {
+		ev.device = qp->ibqp.device;
+		ev.element.qp = &qp->ibqp;
+		ev.event = IB_EVENT_QP_LAST_WQE_REACHED;
+		qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
+	}
+	if (mig) {
+		ev.device = qp->ibqp.device;
+		ev.element.qp = &qp->ibqp;
+		ev.event = IB_EVENT_PATH_MIG;
+		qp->ibqp.event_handler(&ev, qp->ibqp.qp_context);
+	}
+	ret = 0;
+	goto bail;
+
+inval:
+	spin_unlock(&qp->s_lock);
+	spin_unlock_irq(&qp->r_lock);
+	ret = -EINVAL;
+
+bail:
+	return ret;
+}
+
+int qib_query_qp(struct ib_qp *ibqp, struct ib_qp_attr *attr,
+		 int attr_mask, struct ib_qp_init_attr *init_attr)
+{
+	struct qib_qp *qp = to_iqp(ibqp);
+
+	attr->qp_state = qp->state;
+	attr->cur_qp_state = attr->qp_state;
+	attr->path_mtu = qp->path_mtu;
+	attr->path_mig_state = qp->s_mig_state;
+	attr->qkey = qp->qkey;
+	attr->rq_psn = qp->r_psn & QIB_PSN_MASK;
+	attr->sq_psn = qp->s_next_psn & QIB_PSN_MASK;
+	attr->dest_qp_num = qp->remote_qpn;
+	attr->qp_access_flags = qp->qp_access_flags;
+	attr->cap.max_send_wr = qp->s_size - 1;
+	attr->cap.max_recv_wr = qp->ibqp.srq ? 0 : qp->r_rq.size - 1;
+	attr->cap.max_send_sge = qp->s_max_sge;
+	attr->cap.max_recv_sge = qp->r_rq.max_sge;
+	attr->cap.max_inline_data = 0;
+	attr->ah_attr = qp->remote_ah_attr;
+	attr->alt_ah_attr = qp->alt_ah_attr;
+	attr->pkey_index = qp->s_pkey_index;
+	attr->alt_pkey_index = qp->s_alt_pkey_index;
+	attr->en_sqd_async_notify = 0;
+	attr->sq_draining = qp->s_draining;
+	attr->max_rd_atomic = qp->s_max_rd_atomic;
+	attr->max_dest_rd_atomic = qp->r_max_rd_atomic;
+	attr->min_rnr_timer = qp->r_min_rnr_timer;
+	attr->port_num = qp->port_num;
+	attr->timeout = qp->timeout;
+	attr->retry_cnt = qp->s_retry_cnt;
+	attr->rnr_retry = qp->s_rnr_retry_cnt;
+	attr->alt_port_num = qp->alt_ah_attr.port_num;
+	attr->alt_timeout = qp->alt_timeout;
+
+	init_attr->event_handler = qp->ibqp.event_handler;
+	init_attr->qp_context = qp->ibqp.qp_context;
+	init_attr->send_cq = qp->ibqp.send_cq;
+	init_attr->recv_cq = qp->ibqp.recv_cq;
+	init_attr->srq = qp->ibqp.srq;
+	init_attr->cap = attr->cap;
+	if (qp->s_flags & QIB_S_SIGNAL_REQ_WR)
+		init_attr->sq_sig_type = IB_SIGNAL_REQ_WR;
+	else
+		init_attr->sq_sig_type = IB_SIGNAL_ALL_WR;
+	init_attr->qp_type = qp->ibqp.qp_type;
+	init_attr->port_num = qp->port_num;
+	return 0;
+}
+
+/**
+ * qib_compute_aeth - compute the AETH (syndrome + MSN)
+ * @qp: the queue pair to compute the AETH for
+ *
+ * Returns the AETH.
+ */
+__be32 qib_compute_aeth(struct qib_qp *qp)
+{
+	u32 aeth = qp->r_msn & QIB_MSN_MASK;
+
+	if (qp->ibqp.srq) {
+		/*
+		 * Shared receive queues don't generate credits.
+		 * Set the credit field to the invalid value.
+		 */
+		aeth |= QIB_AETH_CREDIT_INVAL << QIB_AETH_CREDIT_SHIFT;
+	} else {
+		u32 min, max, x;
+		u32 credits;
+		struct qib_rwq *wq = qp->r_rq.wq;
+		u32 head;
+		u32 tail;
+
+		/* sanity check pointers before trusting them */
+		head = wq->head;
+		if (head >= qp->r_rq.size)
+			head = 0;
+		tail = wq->tail;
+		if (tail >= qp->r_rq.size)
+			tail = 0;
+		/*
+		 * Compute the number of credits available (RWQEs).
+		 * XXX Not holding the r_rq.lock here so there is a small
+		 * chance that the pair of reads are not atomic.
+		 */
+		credits = head - tail;
+		if ((int)credits < 0)
+			credits += qp->r_rq.size;
+		/*
+		 * Binary search the credit table to find the code to
+		 * use.
+		 */
+		min = 0;
+		max = 31;
+		for (;;) {
+			x = (min + max) / 2;
+			if (credit_table[x] == credits)
+				break;
+			if (credit_table[x] > credits)
+				max = x;
+			else if (min == x)
+				break;
+			else
+				min = x;
+		}
+		aeth |= x << QIB_AETH_CREDIT_SHIFT;
+	}
+	return cpu_to_be32(aeth);
+}
+
+/**
+ * qib_create_qp - create a queue pair for a device
+ * @ibpd: the protection domain who's device we create the queue pair for
+ * @init_attr: the attributes of the queue pair
+ * @udata: user data for libibverbs.so
+ *
+ * Returns the queue pair on success, otherwise returns an errno.
+ *
+ * Called by the ib_create_qp() core verbs function.
+ */
+struct ib_qp *qib_create_qp(struct ib_pd *ibpd,
+			    struct ib_qp_init_attr *init_attr,
+			    struct ib_udata *udata)
+{
+	struct qib_qp *qp;
+	int err;
+	struct qib_swqe *swq = NULL;
+	struct qib_ibdev *dev;
+	struct qib_devdata *dd;
+	size_t sz;
+	size_t sg_list_sz;
+	struct ib_qp *ret;
+
+	if (init_attr->cap.max_send_sge > ib_qib_max_sges ||
+	    init_attr->cap.max_send_wr > ib_qib_max_qp_wrs ||
+	    init_attr->create_flags) {
+		ret = ERR_PTR(-EINVAL);
+		goto bail;
+	}
+
+	/* Check receive queue parameters if no SRQ is specified. */
+	if (!init_attr->srq) {
+		if (init_attr->cap.max_recv_sge > ib_qib_max_sges ||
+		    init_attr->cap.max_recv_wr > ib_qib_max_qp_wrs) {
+			ret = ERR_PTR(-EINVAL);
+			goto bail;
+		}
+		if (init_attr->cap.max_send_sge +
+		    init_attr->cap.max_send_wr +
+		    init_attr->cap.max_recv_sge +
+		    init_attr->cap.max_recv_wr == 0) {
+			ret = ERR_PTR(-EINVAL);
+			goto bail;
+		}
+	}
+
+	switch (init_attr->qp_type) {
+	case IB_QPT_SMI:
+	case IB_QPT_GSI:
+		if (init_attr->port_num == 0 ||
+		    init_attr->port_num > ibpd->device->phys_port_cnt) {
+			ret = ERR_PTR(-EINVAL);
+			goto bail;
+		}
+	case IB_QPT_UC:
+	case IB_QPT_RC:
+	case IB_QPT_UD:
+		sz = sizeof(struct qib_sge) *
+			init_attr->cap.max_send_sge +
+			sizeof(struct qib_swqe);
+		swq = vmalloc((init_attr->cap.max_send_wr + 1) * sz);
+		if (swq == NULL) {
+			ret = ERR_PTR(-ENOMEM);
+			goto bail;
+		}
+		sz = sizeof(*qp);
+		sg_list_sz = 0;
+		if (init_attr->srq) {
+			struct qib_srq *srq = to_isrq(init_attr->srq);
+
+			if (srq->rq.max_sge > 1)
+				sg_list_sz = sizeof(*qp->r_sg_list) *
+					(srq->rq.max_sge - 1);
+		} else if (init_attr->cap.max_recv_sge > 1)
+			sg_list_sz = sizeof(*qp->r_sg_list) *
+				(init_attr->cap.max_recv_sge - 1);
+		qp = kzalloc(sz + sg_list_sz, GFP_KERNEL);
+		if (!qp) {
+			ret = ERR_PTR(-ENOMEM);
+			goto bail_swq;
+		}
+		RCU_INIT_POINTER(qp->next, NULL);
+		qp->s_hdr = kzalloc(sizeof(*qp->s_hdr), GFP_KERNEL);
+		if (!qp->s_hdr) {
+			ret = ERR_PTR(-ENOMEM);
+			goto bail_qp;
+		}
+		qp->timeout_jiffies =
+			usecs_to_jiffies((4096UL * (1UL << qp->timeout)) /
+				1000UL);
+		if (init_attr->srq)
+			sz = 0;
+		else {
+			qp->r_rq.size = init_attr->cap.max_recv_wr + 1;
+			qp->r_rq.max_sge = init_attr->cap.max_recv_sge;
+			sz = (sizeof(struct ib_sge) * qp->r_rq.max_sge) +
+				sizeof(struct qib_rwqe);
+			qp->r_rq.wq = vmalloc_user(sizeof(struct qib_rwq) +
+						   qp->r_rq.size * sz);
+			if (!qp->r_rq.wq) {
+				ret = ERR_PTR(-ENOMEM);
+				goto bail_qp;
+			}
+		}
+
+		/*
+		 * ib_create_qp() will initialize qp->ibqp
+		 * except for qp->ibqp.qp_num.
+		 */
+		spin_lock_init(&qp->r_lock);
+		spin_lock_init(&qp->s_lock);
+		spin_lock_init(&qp->r_rq.lock);
+		atomic_set(&qp->refcount, 0);
+		init_waitqueue_head(&qp->wait);
+		init_waitqueue_head(&qp->wait_dma);
+		init_timer(&qp->s_timer);
+		qp->s_timer.data = (unsigned long)qp;
+		INIT_WORK(&qp->s_work, qib_do_send);
+		INIT_LIST_HEAD(&qp->iowait);
+		INIT_LIST_HEAD(&qp->rspwait);
+		qp->state = IB_QPS_RESET;
+		qp->s_wq = swq;
+		qp->s_size = init_attr->cap.max_send_wr + 1;
+		qp->s_max_sge = init_attr->cap.max_send_sge;
+		if (init_attr->sq_sig_type == IB_SIGNAL_REQ_WR)
+			qp->s_flags = QIB_S_SIGNAL_REQ_WR;
+		dev = to_idev(ibpd->device);
+		dd = dd_from_dev(dev);
+		err = alloc_qpn(dd, &dev->qpn_table, init_attr->qp_type,
+				init_attr->port_num);
+		if (err < 0) {
+			ret = ERR_PTR(err);
+			vfree(qp->r_rq.wq);
+			goto bail_qp;
+		}
+		qp->ibqp.qp_num = err;
+		qp->port_num = init_attr->port_num;
+		qib_reset_qp(qp, init_attr->qp_type);
+		break;
+
+	default:
+		/* Don't support raw QPs */
+		ret = ERR_PTR(-ENOSYS);
+		goto bail;
+	}
+
+	init_attr->cap.max_inline_data = 0;
+
+	/*
+	 * Return the address of the RWQ as the offset to mmap.
+	 * See qib_mmap() for details.
+	 */
+	if (udata && udata->outlen >= sizeof(__u64)) {
+		if (!qp->r_rq.wq) {
+			__u64 offset = 0;
+
+			err = ib_copy_to_udata(udata, &offset,
+					       sizeof(offset));
+			if (err) {
+				ret = ERR_PTR(err);
+				goto bail_ip;
+			}
+		} else {
+			u32 s = sizeof(struct qib_rwq) + qp->r_rq.size * sz;
+
+			qp->ip = qib_create_mmap_info(dev, s,
+						      ibpd->uobject->context,
+						      qp->r_rq.wq);
+			if (!qp->ip) {
+				ret = ERR_PTR(-ENOMEM);
+				goto bail_ip;
+			}
+
+			err = ib_copy_to_udata(udata, &(qp->ip->offset),
+					       sizeof(qp->ip->offset));
+			if (err) {
+				ret = ERR_PTR(err);
+				goto bail_ip;
+			}
+		}
+	}
+
+	spin_lock(&dev->n_qps_lock);
+	if (dev->n_qps_allocated == ib_qib_max_qps) {
+		spin_unlock(&dev->n_qps_lock);
+		ret = ERR_PTR(-ENOMEM);
+		goto bail_ip;
+	}
+
+	dev->n_qps_allocated++;
+	spin_unlock(&dev->n_qps_lock);
+
+	if (qp->ip) {
+		spin_lock_irq(&dev->pending_lock);
+		list_add(&qp->ip->pending_mmaps, &dev->pending_mmaps);
+		spin_unlock_irq(&dev->pending_lock);
+	}
+
+	ret = &qp->ibqp;
+	goto bail;
+
+bail_ip:
+	if (qp->ip)
+		kref_put(&qp->ip->ref, qib_release_mmap_info);
+	else
+		vfree(qp->r_rq.wq);
+	free_qpn(&dev->qpn_table, qp->ibqp.qp_num);
+bail_qp:
+	kfree(qp->s_hdr);
+	kfree(qp);
+bail_swq:
+	vfree(swq);
+bail:
+	return ret;
+}
+
+/**
+ * qib_destroy_qp - destroy a queue pair
+ * @ibqp: the queue pair to destroy
+ *
+ * Returns 0 on success.
+ *
+ * Note that this can be called while the QP is actively sending or
+ * receiving!
+ */
+int qib_destroy_qp(struct ib_qp *ibqp)
+{
+	struct qib_qp *qp = to_iqp(ibqp);
+	struct qib_ibdev *dev = to_idev(ibqp->device);
+
+	/* Make sure HW and driver activity is stopped. */
+	spin_lock_irq(&qp->s_lock);
+	if (qp->state != IB_QPS_RESET) {
+		qp->state = IB_QPS_RESET;
+		spin_lock(&dev->pending_lock);
+		if (!list_empty(&qp->iowait))
+			list_del_init(&qp->iowait);
+		spin_unlock(&dev->pending_lock);
+		qp->s_flags &= ~(QIB_S_TIMER | QIB_S_ANY_WAIT);
+		spin_unlock_irq(&qp->s_lock);
+		cancel_work_sync(&qp->s_work);
+		del_timer_sync(&qp->s_timer);
+		wait_event(qp->wait_dma, !atomic_read(&qp->s_dma_busy));
+		if (qp->s_tx) {
+			qib_put_txreq(qp->s_tx);
+			qp->s_tx = NULL;
+		}
+		remove_qp(dev, qp);
+		wait_event(qp->wait, !atomic_read(&qp->refcount));
+		clear_mr_refs(qp, 1);
+	} else
+		spin_unlock_irq(&qp->s_lock);
+
+	/* all user's cleaned up, mark it available */
+	free_qpn(&dev->qpn_table, qp->ibqp.qp_num);
+	spin_lock(&dev->n_qps_lock);
+	dev->n_qps_allocated--;
+	spin_unlock(&dev->n_qps_lock);
+
+	if (qp->ip)
+		kref_put(&qp->ip->ref, qib_release_mmap_info);
+	else
+		vfree(qp->r_rq.wq);
+	vfree(qp->s_wq);
+	kfree(qp->s_hdr);
+	kfree(qp);
+	return 0;
+}
+
+/**
+ * qib_init_qpn_table - initialize the QP number table for a device
+ * @qpt: the QPN table
+ */
+void qib_init_qpn_table(struct qib_devdata *dd, struct qib_qpn_table *qpt)
+{
+	spin_lock_init(&qpt->lock);
+	qpt->last = 1;          /* start with QPN 2 */
+	qpt->nmaps = 1;
+	qpt->mask = dd->qpn_mask;
+}
+
+/**
+ * qib_free_qpn_table - free the QP number table for a device
+ * @qpt: the QPN table
+ */
+void qib_free_qpn_table(struct qib_qpn_table *qpt)
+{
+	int i;
+
+	for (i = 0; i < ARRAY_SIZE(qpt->map); i++)
+		if (qpt->map[i].page)
+			free_page((unsigned long) qpt->map[i].page);
+}
+
+/**
+ * qib_get_credit - flush the send work queue of a QP
+ * @qp: the qp who's send work queue to flush
+ * @aeth: the Acknowledge Extended Transport Header
+ *
+ * The QP s_lock should be held.
+ */
+void qib_get_credit(struct qib_qp *qp, u32 aeth)
+{
+	u32 credit = (aeth >> QIB_AETH_CREDIT_SHIFT) & QIB_AETH_CREDIT_MASK;
+
+	/*
+	 * If the credit is invalid, we can send
+	 * as many packets as we like.  Otherwise, we have to
+	 * honor the credit field.
+	 */
+	if (credit == QIB_AETH_CREDIT_INVAL) {
+		if (!(qp->s_flags & QIB_S_UNLIMITED_CREDIT)) {
+			qp->s_flags |= QIB_S_UNLIMITED_CREDIT;
+			if (qp->s_flags & QIB_S_WAIT_SSN_CREDIT) {
+				qp->s_flags &= ~QIB_S_WAIT_SSN_CREDIT;
+				qib_schedule_send(qp);
+			}
+		}
+	} else if (!(qp->s_flags & QIB_S_UNLIMITED_CREDIT)) {
+		/* Compute new LSN (i.e., MSN + credit) */
+		credit = (aeth + credit_table[credit]) & QIB_MSN_MASK;
+		if (qib_cmp24(credit, qp->s_lsn) > 0) {
+			qp->s_lsn = credit;
+			if (qp->s_flags & QIB_S_WAIT_SSN_CREDIT) {
+				qp->s_flags &= ~QIB_S_WAIT_SSN_CREDIT;
+				qib_schedule_send(qp);
+			}
+		}
+	}
+}
+
+#ifdef CONFIG_DEBUG_FS
+
+struct qib_qp_iter {
+	struct qib_ibdev *dev;
+	struct qib_qp *qp;
+	int n;
+};
+
+struct qib_qp_iter *qib_qp_iter_init(struct qib_ibdev *dev)
+{
+	struct qib_qp_iter *iter;
+
+	iter = kzalloc(sizeof(*iter), GFP_KERNEL);
+	if (!iter)
+		return NULL;
+
+	iter->dev = dev;
+	if (qib_qp_iter_next(iter)) {
+		kfree(iter);
+		return NULL;
+	}
+
+	return iter;
+}
+
+int qib_qp_iter_next(struct qib_qp_iter *iter)
+{
+	struct qib_ibdev *dev = iter->dev;
+	int n = iter->n;
+	int ret = 1;
+	struct qib_qp *pqp = iter->qp;
+	struct qib_qp *qp;
+
+	for (; n < dev->qp_table_size; n++) {
+		if (pqp)
+			qp = rcu_dereference(pqp->next);
+		else
+			qp = rcu_dereference(dev->qp_table[n]);
+		pqp = qp;
+		if (qp) {
+			iter->qp = qp;
+			iter->n = n;
+			return 0;
+		}
+	}
+	return ret;
+}
+
+static const char * const qp_type_str[] = {
+	"SMI", "GSI", "RC", "UC", "UD",
+};
+
+void qib_qp_iter_print(struct seq_file *s, struct qib_qp_iter *iter)
+{
+	struct qib_swqe *wqe;
+	struct qib_qp *qp = iter->qp;
+
+	wqe = get_swqe_ptr(qp, qp->s_last);
+	seq_printf(s,
+		   "N %d QP%u %s %u %u %u f=%x %u %u %u %u %u PSN %x %x %x %x %x (%u %u %u %u %u %u) QP%u LID %x\n",
+		   iter->n,
+		   qp->ibqp.qp_num,
+		   qp_type_str[qp->ibqp.qp_type],
+		   qp->state,
+		   wqe->wr.opcode,
+		   qp->s_hdrwords,
+		   qp->s_flags,
+		   atomic_read(&qp->s_dma_busy),
+		   !list_empty(&qp->iowait),
+		   qp->timeout,
+		   wqe->ssn,
+		   qp->s_lsn,
+		   qp->s_last_psn,
+		   qp->s_psn, qp->s_next_psn,
+		   qp->s_sending_psn, qp->s_sending_hpsn,
+		   qp->s_last, qp->s_acked, qp->s_cur,
+		   qp->s_tail, qp->s_head, qp->s_size,
+		   qp->remote_qpn,
+		   qp->remote_ah_attr.dlid);
+}
+
+#endif