IB/ipath: misc infiniband code, part 1

Completion queues, local and remote memory keys, and memory region
support.

Signed-off-by: Bryan O'Sullivan <bos@pathscale.com>
Signed-off-by: Roland Dreier <rolandd@cisco.com>

1 files changed, 295 insertions, 0 deletions

diff --git a/drivers/infiniband/hw/ipath/ipath_cq.c b/drivers/infiniband/hw/ipath/ipath_cq.c
new file mode 100644
index 00000000000..7ece1135ddf
--- /dev/null
+++ b/drivers/infiniband/hw/ipath/ipath_cq.c
@@ -0,0 +1,295 @@
+/*
+ * 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 "ipath_verbs.h"
+
+/**
+ * ipath_cq_enter - add a new entry to the completion queue
+ * @cq: completion queue
+ * @entry: work completion entry to add
+ * @sig: true if @entry is a solicitated entry
+ *
+ * This may be called with one of the qp->s_lock or qp->r_rq.lock held.
+ */
+void ipath_cq_enter(struct ipath_cq *cq, struct ib_wc *entry, int solicited)
+{
+	unsigned long flags;
+	u32 next;
+
+	spin_lock_irqsave(&cq->lock, flags);
+
+	if (cq->head == cq->ibcq.cqe)
+		next = 0;
+	else
+		next = cq->head + 1;
+	if (unlikely(next == cq->tail)) {
+		spin_unlock_irqrestore(&cq->lock, flags);
+		if (cq->ibcq.event_handler) {
+			struct ib_event ev;
+
+			ev.device = cq->ibcq.device;
+			ev.element.cq = &cq->ibcq;
+			ev.event = IB_EVENT_CQ_ERR;
+			cq->ibcq.event_handler(&ev, cq->ibcq.cq_context);
+		}
+		return;
+	}
+	cq->queue[cq->head] = *entry;
+	cq->head = next;
+
+	if (cq->notify == IB_CQ_NEXT_COMP ||
+	    (cq->notify == IB_CQ_SOLICITED && solicited)) {
+		cq->notify = IB_CQ_NONE;
+		cq->triggered++;
+		/*
+		 * This will cause send_complete() to be called in
+		 * another thread.
+		 */
+		tasklet_hi_schedule(&cq->comptask);
+	}
+
+	spin_unlock_irqrestore(&cq->lock, flags);
+
+	if (entry->status != IB_WC_SUCCESS)
+		to_idev(cq->ibcq.device)->n_wqe_errs++;
+}
+
+/**
+ * ipath_poll_cq - poll for work completion entries
+ * @ibcq: the completion queue to poll
+ * @num_entries: the maximum number of entries to return
+ * @entry: pointer to array where work completions are placed
+ *
+ * Returns the number of completion entries polled.
+ *
+ * This may be called from interrupt context.  Also called by ib_poll_cq()
+ * in the generic verbs code.
+ */
+int ipath_poll_cq(struct ib_cq *ibcq, int num_entries, struct ib_wc *entry)
+{
+	struct ipath_cq *cq = to_icq(ibcq);
+	unsigned long flags;
+	int npolled;
+
+	spin_lock_irqsave(&cq->lock, flags);
+
+	for (npolled = 0; npolled < num_entries; ++npolled, ++entry) {
+		if (cq->tail == cq->head)
+			break;
+		*entry = cq->queue[cq->tail];
+		if (cq->tail == cq->ibcq.cqe)
+			cq->tail = 0;
+		else
+			cq->tail++;
+	}
+
+	spin_unlock_irqrestore(&cq->lock, flags);
+
+	return npolled;
+}
+
+static void send_complete(unsigned long data)
+{
+	struct ipath_cq *cq = (struct ipath_cq *)data;
+
+	/*
+	 * The completion handler will most likely rearm the notification
+	 * and poll for all pending entries.  If a new completion entry
+	 * is added while we are in this routine, tasklet_hi_schedule()
+	 * won't call us again until we return so we check triggered to
+	 * see if we need to call the handler again.
+	 */
+	for (;;) {
+		u8 triggered = cq->triggered;
+
+		cq->ibcq.comp_handler(&cq->ibcq, cq->ibcq.cq_context);
+
+		if (cq->triggered == triggered)
+			return;
+	}
+}
+
+/**
+ * ipath_create_cq - create a completion queue
+ * @ibdev: the device this completion queue is attached to
+ * @entries: the minimum size of the completion queue
+ * @context: unused by the InfiniPath driver
+ * @udata: unused by the InfiniPath driver
+ *
+ * Returns a pointer to the completion queue or negative errno values
+ * for failure.
+ *
+ * Called by ib_create_cq() in the generic verbs code.
+ */
+struct ib_cq *ipath_create_cq(struct ib_device *ibdev, int entries,
+			      struct ib_ucontext *context,
+			      struct ib_udata *udata)
+{
+	struct ipath_cq *cq;
+	struct ib_wc *wc;
+	struct ib_cq *ret;
+
+	/*
+	 * Need to use vmalloc() if we want to support large #s of
+	 * entries.
+	 */
+	cq = kmalloc(sizeof(*cq), GFP_KERNEL);
+	if (!cq) {
+		ret = ERR_PTR(-ENOMEM);
+		goto bail;
+	}
+
+	/*
+	 * Need to use vmalloc() if we want to support large #s of entries.
+	 */
+	wc = vmalloc(sizeof(*wc) * (entries + 1));
+	if (!wc) {
+		kfree(cq);
+		ret = ERR_PTR(-ENOMEM);
+		goto bail;
+	}
+	/*
+	 * ib_create_cq() will initialize cq->ibcq except for cq->ibcq.cqe.
+	 * The number of entries should be >= the number requested or return
+	 * an error.
+	 */
+	cq->ibcq.cqe = entries;
+	cq->notify = IB_CQ_NONE;
+	cq->triggered = 0;
+	spin_lock_init(&cq->lock);
+	tasklet_init(&cq->comptask, send_complete, (unsigned long)cq);
+	cq->head = 0;
+	cq->tail = 0;
+	cq->queue = wc;
+
+	ret = &cq->ibcq;
+
+bail:
+	return ret;
+}
+
+/**
+ * ipath_destroy_cq - destroy a completion queue
+ * @ibcq: the completion queue to destroy.
+ *
+ * Returns 0 for success.
+ *
+ * Called by ib_destroy_cq() in the generic verbs code.
+ */
+int ipath_destroy_cq(struct ib_cq *ibcq)
+{
+	struct ipath_cq *cq = to_icq(ibcq);
+
+	tasklet_kill(&cq->comptask);
+	vfree(cq->queue);
+	kfree(cq);
+
+	return 0;
+}
+
+/**
+ * ipath_req_notify_cq - change the notification type for a completion queue
+ * @ibcq: the completion queue
+ * @notify: the type of notification to request
+ *
+ * Returns 0 for success.
+ *
+ * This may be called from interrupt context.  Also called by
+ * ib_req_notify_cq() in the generic verbs code.
+ */
+int ipath_req_notify_cq(struct ib_cq *ibcq, enum ib_cq_notify notify)
+{
+	struct ipath_cq *cq = to_icq(ibcq);
+	unsigned long flags;
+
+	spin_lock_irqsave(&cq->lock, flags);
+	/*
+	 * Don't change IB_CQ_NEXT_COMP to IB_CQ_SOLICITED but allow
+	 * any other transitions.
+	 */
+	if (cq->notify != IB_CQ_NEXT_COMP)
+		cq->notify = notify;
+	spin_unlock_irqrestore(&cq->lock, flags);
+	return 0;
+}
+
+int ipath_resize_cq(struct ib_cq *ibcq, int cqe, struct ib_udata *udata)
+{
+	struct ipath_cq *cq = to_icq(ibcq);
+	struct ib_wc *wc, *old_wc;
+	u32 n;
+	int ret;
+
+	/*
+	 * Need to use vmalloc() if we want to support large #s of entries.
+	 */
+	wc = vmalloc(sizeof(*wc) * (cqe + 1));
+	if (!wc) {
+		ret = -ENOMEM;
+		goto bail;
+	}
+
+	spin_lock_irq(&cq->lock);
+	if (cq->head < cq->tail)
+		n = cq->ibcq.cqe + 1 + cq->head - cq->tail;
+	else
+		n = cq->head - cq->tail;
+	if (unlikely((u32)cqe < n)) {
+		spin_unlock_irq(&cq->lock);
+		vfree(wc);
+		ret = -EOVERFLOW;
+		goto bail;
+	}
+	for (n = 0; cq->tail != cq->head; n++) {
+		wc[n] = cq->queue[cq->tail];
+		if (cq->tail == cq->ibcq.cqe)
+			cq->tail = 0;
+		else
+			cq->tail++;
+	}
+	cq->ibcq.cqe = cqe;
+	cq->head = n;
+	cq->tail = 0;
+	old_wc = cq->queue;
+	cq->queue = wc;
+	spin_unlock_irq(&cq->lock);
+
+	vfree(old_wc);
+
+	ret = 0;
+
+bail:
+	return ret;
+}