[PATCH] IB: Add RMPP implementation

Add RMPP implementation.

Signed-off-by: Sean Hefty <sean.hefty@intel.com>
Signed-off-by: Hal Rosenstock <halr@voltaire.com>
Cc: Roland Dreier <rolandd@cisco.com>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>

1 files changed, 765 insertions, 0 deletions

diff --git a/drivers/infiniband/core/mad_rmpp.c b/drivers/infiniband/core/mad_rmpp.c
new file mode 100644
index 000000000000..8f1eb80e421f
--- /dev/null
+++ b/drivers/infiniband/core/mad_rmpp.c
@@ -0,0 +1,765 @@
+/*
+ * Copyright (c) 2005 Intel Inc. All rights reserved.
+ * Copyright (c) 2005 Voltaire, 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.
+ *
+ * $Id: mad_rmpp.c 1921 2005-03-02 22:58:44Z sean.hefty $
+ */
+
+#include <linux/dma-mapping.h>
+
+#include "mad_priv.h"
+#include "mad_rmpp.h"
+
+enum rmpp_state {
+	RMPP_STATE_ACTIVE,
+	RMPP_STATE_TIMEOUT,
+	RMPP_STATE_COMPLETE
+};
+
+struct mad_rmpp_recv {
+	struct ib_mad_agent_private *agent;
+	struct list_head list;
+	struct work_struct timeout_work;
+	struct work_struct cleanup_work;
+	wait_queue_head_t wait;
+	enum rmpp_state state;
+	spinlock_t lock;
+	atomic_t refcount;
+
+	struct ib_ah *ah;
+	struct ib_mad_recv_wc *rmpp_wc;
+	struct ib_mad_recv_buf *cur_seg_buf;
+	int last_ack;
+	int seg_num;
+	int newwin;
+
+	u64 tid;
+	u32 src_qp;
+	u16 slid;
+	u8 mgmt_class;
+	u8 class_version;
+	u8 method;
+};
+
+static void destroy_rmpp_recv(struct mad_rmpp_recv *rmpp_recv)
+{
+	atomic_dec(&rmpp_recv->refcount);
+	wait_event(rmpp_recv->wait, !atomic_read(&rmpp_recv->refcount));
+	ib_destroy_ah(rmpp_recv->ah);
+	kfree(rmpp_recv);
+}
+
+void ib_cancel_rmpp_recvs(struct ib_mad_agent_private *agent)
+{
+	struct mad_rmpp_recv *rmpp_recv, *temp_rmpp_recv;
+	unsigned long flags;
+
+	spin_lock_irqsave(&agent->lock, flags);
+	list_for_each_entry(rmpp_recv, &agent->rmpp_list, list) {
+		cancel_delayed_work(&rmpp_recv->timeout_work);
+		cancel_delayed_work(&rmpp_recv->cleanup_work);
+	}
+	spin_unlock_irqrestore(&agent->lock, flags);
+
+	flush_workqueue(agent->qp_info->port_priv->wq);
+
+	list_for_each_entry_safe(rmpp_recv, temp_rmpp_recv,
+				 &agent->rmpp_list, list) {
+		list_del(&rmpp_recv->list);
+		if (rmpp_recv->state != RMPP_STATE_COMPLETE)
+			ib_free_recv_mad(rmpp_recv->rmpp_wc);
+		destroy_rmpp_recv(rmpp_recv);
+	}
+}
+
+static void recv_timeout_handler(void *data)
+{
+	struct mad_rmpp_recv *rmpp_recv = data;
+	struct ib_mad_recv_wc *rmpp_wc;
+	unsigned long flags;
+
+	spin_lock_irqsave(&rmpp_recv->agent->lock, flags);
+	if (rmpp_recv->state != RMPP_STATE_ACTIVE) {
+		spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);
+		return;
+	}
+	rmpp_recv->state = RMPP_STATE_TIMEOUT;
+	list_del(&rmpp_recv->list);
+	spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);
+
+	/* TODO: send abort. */
+	rmpp_wc = rmpp_recv->rmpp_wc;
+	destroy_rmpp_recv(rmpp_recv);
+	ib_free_recv_mad(rmpp_wc);
+}
+
+static void recv_cleanup_handler(void *data)
+{
+	struct mad_rmpp_recv *rmpp_recv = data;
+	unsigned long flags;
+
+	spin_lock_irqsave(&rmpp_recv->agent->lock, flags);
+	list_del(&rmpp_recv->list);
+	spin_unlock_irqrestore(&rmpp_recv->agent->lock, flags);
+	destroy_rmpp_recv(rmpp_recv);
+}
+
+static struct mad_rmpp_recv *
+create_rmpp_recv(struct ib_mad_agent_private *agent,
+		 struct ib_mad_recv_wc *mad_recv_wc)
+{
+	struct mad_rmpp_recv *rmpp_recv;
+	struct ib_mad_hdr *mad_hdr;
+
+	rmpp_recv = kmalloc(sizeof *rmpp_recv, GFP_KERNEL);
+	if (!rmpp_recv)
+		return NULL;
+
+	rmpp_recv->ah = ib_create_ah_from_wc(agent->agent.qp->pd,
+					     mad_recv_wc->wc,
+					     mad_recv_wc->recv_buf.grh,
+					     agent->agent.port_num);
+	if (IS_ERR(rmpp_recv->ah))
+		goto error;
+
+	rmpp_recv->agent = agent;
+	init_waitqueue_head(&rmpp_recv->wait);
+	INIT_WORK(&rmpp_recv->timeout_work, recv_timeout_handler, rmpp_recv);
+	INIT_WORK(&rmpp_recv->cleanup_work, recv_cleanup_handler, rmpp_recv);
+	spin_lock_init(&rmpp_recv->lock);
+	rmpp_recv->state = RMPP_STATE_ACTIVE;
+	atomic_set(&rmpp_recv->refcount, 1);
+
+	rmpp_recv->rmpp_wc = mad_recv_wc;
+	rmpp_recv->cur_seg_buf = &mad_recv_wc->recv_buf;
+	rmpp_recv->newwin = 1;
+	rmpp_recv->seg_num = 1;
+	rmpp_recv->last_ack = 0;
+
+	mad_hdr = &mad_recv_wc->recv_buf.mad->mad_hdr;
+	rmpp_recv->tid = mad_hdr->tid;
+	rmpp_recv->src_qp = mad_recv_wc->wc->src_qp;
+	rmpp_recv->slid = mad_recv_wc->wc->slid;
+	rmpp_recv->mgmt_class = mad_hdr->mgmt_class;
+	rmpp_recv->class_version = mad_hdr->class_version;
+	rmpp_recv->method  = mad_hdr->method;
+	return rmpp_recv;
+
+error:	kfree(rmpp_recv);
+	return NULL;
+}
+
+static inline void deref_rmpp_recv(struct mad_rmpp_recv *rmpp_recv)
+{
+	if (atomic_dec_and_test(&rmpp_recv->refcount))
+		wake_up(&rmpp_recv->wait);
+}
+
+static struct mad_rmpp_recv *
+find_rmpp_recv(struct ib_mad_agent_private *agent,
+	       struct ib_mad_recv_wc *mad_recv_wc)
+{
+	struct mad_rmpp_recv *rmpp_recv;
+	struct ib_mad_hdr *mad_hdr = &mad_recv_wc->recv_buf.mad->mad_hdr;
+
+	list_for_each_entry(rmpp_recv, &agent->rmpp_list, list) {
+		if (rmpp_recv->tid == mad_hdr->tid &&
+		    rmpp_recv->src_qp == mad_recv_wc->wc->src_qp &&
+		    rmpp_recv->slid == mad_recv_wc->wc->slid &&
+		    rmpp_recv->mgmt_class == mad_hdr->mgmt_class &&
+		    rmpp_recv->class_version == mad_hdr->class_version &&
+		    rmpp_recv->method == mad_hdr->method)
+			return rmpp_recv;
+	}
+	return NULL;
+}
+
+static struct mad_rmpp_recv *
+acquire_rmpp_recv(struct ib_mad_agent_private *agent,
+		  struct ib_mad_recv_wc *mad_recv_wc)
+{
+	struct mad_rmpp_recv *rmpp_recv;
+	unsigned long flags;
+
+	spin_lock_irqsave(&agent->lock, flags);
+	rmpp_recv = find_rmpp_recv(agent, mad_recv_wc);
+	if (rmpp_recv)
+		atomic_inc(&rmpp_recv->refcount);
+	spin_unlock_irqrestore(&agent->lock, flags);
+	return rmpp_recv;
+}
+
+static struct mad_rmpp_recv *
+insert_rmpp_recv(struct ib_mad_agent_private *agent,
+		 struct mad_rmpp_recv *rmpp_recv)
+{
+	struct mad_rmpp_recv *cur_rmpp_recv;
+
+	cur_rmpp_recv = find_rmpp_recv(agent, rmpp_recv->rmpp_wc);
+	if (!cur_rmpp_recv)
+		list_add_tail(&rmpp_recv->list, &agent->rmpp_list);
+
+	return cur_rmpp_recv;
+}
+
+static int data_offset(u8 mgmt_class)
+{
+	if (mgmt_class == IB_MGMT_CLASS_SUBN_ADM)
+		return offsetof(struct ib_sa_mad, data);
+	else if ((mgmt_class >= IB_MGMT_CLASS_VENDOR_RANGE2_START) &&
+		 (mgmt_class <= IB_MGMT_CLASS_VENDOR_RANGE2_END))
+		return offsetof(struct ib_vendor_mad, data);
+	else
+		return offsetof(struct ib_rmpp_mad, data);
+}
+
+static void format_ack(struct ib_rmpp_mad *ack,
+		       struct ib_rmpp_mad *data,
+		       struct mad_rmpp_recv *rmpp_recv)
+{
+	unsigned long flags;
+
+	memcpy(&ack->mad_hdr, &data->mad_hdr,
+	       data_offset(data->mad_hdr.mgmt_class));
+
+	ack->mad_hdr.method ^= IB_MGMT_METHOD_RESP;
+	ack->rmpp_hdr.rmpp_type = IB_MGMT_RMPP_TYPE_ACK;
+	ib_set_rmpp_flags(&ack->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
+
+	spin_lock_irqsave(&rmpp_recv->lock, flags);
+	rmpp_recv->last_ack = rmpp_recv->seg_num;
+	ack->rmpp_hdr.seg_num = cpu_to_be32(rmpp_recv->seg_num);
+	ack->rmpp_hdr.paylen_newwin = cpu_to_be32(rmpp_recv->newwin);
+	spin_unlock_irqrestore(&rmpp_recv->lock, flags);
+}
+
+static void ack_recv(struct mad_rmpp_recv *rmpp_recv,
+		     struct ib_mad_recv_wc *recv_wc)
+{
+	struct ib_mad_send_buf *msg;
+	struct ib_send_wr *bad_send_wr;
+	int hdr_len, ret;
+
+	hdr_len = sizeof(struct ib_mad_hdr) + sizeof(struct ib_rmpp_hdr);
+	msg = ib_create_send_mad(&rmpp_recv->agent->agent, recv_wc->wc->src_qp,
+				 recv_wc->wc->pkey_index, rmpp_recv->ah, 1,
+				 hdr_len, sizeof(struct ib_rmpp_mad) - hdr_len,
+				 GFP_KERNEL);
+	if (!msg)
+		return;
+
+	format_ack((struct ib_rmpp_mad *) msg->mad,
+		   (struct ib_rmpp_mad *) recv_wc->recv_buf.mad, rmpp_recv);
+	ret = ib_post_send_mad(&rmpp_recv->agent->agent, &msg->send_wr,
+			       &bad_send_wr);
+	if (ret)
+		ib_free_send_mad(msg);
+}
+
+static inline int get_last_flag(struct ib_mad_recv_buf *seg)
+{
+	struct ib_rmpp_mad *rmpp_mad;
+
+	rmpp_mad = (struct ib_rmpp_mad *) seg->mad;
+	return ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) & IB_MGMT_RMPP_FLAG_LAST;
+}
+
+static inline int get_seg_num(struct ib_mad_recv_buf *seg)
+{
+	struct ib_rmpp_mad *rmpp_mad;
+
+	rmpp_mad = (struct ib_rmpp_mad *) seg->mad;
+	return be32_to_cpu(rmpp_mad->rmpp_hdr.seg_num);
+}
+
+static inline struct ib_mad_recv_buf * get_next_seg(struct list_head *rmpp_list,
+						    struct ib_mad_recv_buf *seg)
+{
+	if (seg->list.next == rmpp_list)
+		return NULL;
+
+	return container_of(seg->list.next, struct ib_mad_recv_buf, list);
+}
+
+static inline int window_size(struct ib_mad_agent_private *agent)
+{
+	return max(agent->qp_info->recv_queue.max_active >> 3, 1);
+}
+
+static struct ib_mad_recv_buf * find_seg_location(struct list_head *rmpp_list,
+						  int seg_num)
+{
+        struct ib_mad_recv_buf *seg_buf;
+	int cur_seg_num;
+
+	list_for_each_entry_reverse(seg_buf, rmpp_list, list) {
+		cur_seg_num = get_seg_num(seg_buf);
+		if (seg_num > cur_seg_num)
+			return seg_buf;
+		if (seg_num == cur_seg_num)
+			break;
+	}
+	return NULL;
+}
+
+static void update_seg_num(struct mad_rmpp_recv *rmpp_recv,
+			   struct ib_mad_recv_buf *new_buf)
+{
+	struct list_head *rmpp_list = &rmpp_recv->rmpp_wc->rmpp_list;
+
+	while (new_buf && (get_seg_num(new_buf) == rmpp_recv->seg_num + 1)) {
+		rmpp_recv->cur_seg_buf = new_buf;
+		rmpp_recv->seg_num++;
+		new_buf = get_next_seg(rmpp_list, new_buf);
+	}
+}
+
+static inline int get_mad_len(struct mad_rmpp_recv *rmpp_recv)
+{
+	struct ib_rmpp_mad *rmpp_mad;
+	int hdr_size, data_size, pad;
+
+	rmpp_mad = (struct ib_rmpp_mad *)rmpp_recv->cur_seg_buf->mad;
+
+	hdr_size = data_offset(rmpp_mad->mad_hdr.mgmt_class);
+	data_size = sizeof(struct ib_rmpp_mad) - hdr_size;
+	pad = data_size - be32_to_cpu(rmpp_mad->rmpp_hdr.paylen_newwin);
+	if (pad > data_size || pad < 0)
+		pad = 0;
+
+	return hdr_size + rmpp_recv->seg_num * data_size - pad;
+}
+
+static struct ib_mad_recv_wc * complete_rmpp(struct mad_rmpp_recv *rmpp_recv)
+{
+	struct ib_mad_recv_wc *rmpp_wc;
+
+	ack_recv(rmpp_recv, rmpp_recv->rmpp_wc);
+	if (rmpp_recv->seg_num > 1)
+		cancel_delayed_work(&rmpp_recv->timeout_work);
+
+	rmpp_wc = rmpp_recv->rmpp_wc;
+	rmpp_wc->mad_len = get_mad_len(rmpp_recv);
+	/* 10 seconds until we can find the packet lifetime */
+	queue_delayed_work(rmpp_recv->agent->qp_info->port_priv->wq,
+			   &rmpp_recv->cleanup_work, msecs_to_jiffies(10000));
+	return rmpp_wc;
+}
+
+void ib_coalesce_recv_mad(struct ib_mad_recv_wc *mad_recv_wc, void *buf)
+{
+	struct ib_mad_recv_buf *seg_buf;
+	struct ib_rmpp_mad *rmpp_mad;
+	void *data;
+	int size, len, offset;
+	u8 flags;
+
+	len = mad_recv_wc->mad_len;
+	if (len <= sizeof(struct ib_mad)) {
+		memcpy(buf, mad_recv_wc->recv_buf.mad, len);
+		return;
+	}
+
+	offset = data_offset(mad_recv_wc->recv_buf.mad->mad_hdr.mgmt_class);
+
+	list_for_each_entry(seg_buf, &mad_recv_wc->rmpp_list, list) {
+		rmpp_mad = (struct ib_rmpp_mad *)seg_buf->mad;
+		flags = ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr);
+
+		if (flags & IB_MGMT_RMPP_FLAG_FIRST) {
+			data = rmpp_mad;
+			size = sizeof(*rmpp_mad);
+		} else {
+			data = (void *) rmpp_mad + offset;
+			if (flags & IB_MGMT_RMPP_FLAG_LAST)
+				size = len;
+			else
+				size = sizeof(*rmpp_mad) - offset;
+		}
+
+		memcpy(buf, data, size);
+		len -= size;
+		buf += size;
+	}
+}
+EXPORT_SYMBOL(ib_coalesce_recv_mad);
+
+static struct ib_mad_recv_wc *
+continue_rmpp(struct ib_mad_agent_private *agent,
+	      struct ib_mad_recv_wc *mad_recv_wc)
+{
+	struct mad_rmpp_recv *rmpp_recv;
+	struct ib_mad_recv_buf *prev_buf;
+	struct ib_mad_recv_wc *done_wc;
+	int seg_num;
+	unsigned long flags;
+
+	rmpp_recv = acquire_rmpp_recv(agent, mad_recv_wc);
+	if (!rmpp_recv)
+		goto drop1;
+
+	seg_num = get_seg_num(&mad_recv_wc->recv_buf);
+
+	spin_lock_irqsave(&rmpp_recv->lock, flags);
+	if ((rmpp_recv->state == RMPP_STATE_TIMEOUT) ||
+	    (seg_num > rmpp_recv->newwin))
+		goto drop3;
+
+	if ((seg_num <= rmpp_recv->last_ack) ||
+	    (rmpp_recv->state == RMPP_STATE_COMPLETE)) {
+		spin_unlock_irqrestore(&rmpp_recv->lock, flags);
+		ack_recv(rmpp_recv, mad_recv_wc);
+		goto drop2;
+	}
+
+	prev_buf = find_seg_location(&rmpp_recv->rmpp_wc->rmpp_list, seg_num);
+	if (!prev_buf)
+		goto drop3;
+
+	done_wc = NULL;
+	list_add(&mad_recv_wc->recv_buf.list, &prev_buf->list);
+	if (rmpp_recv->cur_seg_buf == prev_buf) {
+		update_seg_num(rmpp_recv, &mad_recv_wc->recv_buf);
+		if (get_last_flag(rmpp_recv->cur_seg_buf)) {
+			rmpp_recv->state = RMPP_STATE_COMPLETE;
+			spin_unlock_irqrestore(&rmpp_recv->lock, flags);
+			done_wc = complete_rmpp(rmpp_recv);
+			goto out;
+		} else if (rmpp_recv->seg_num == rmpp_recv->newwin) {
+			rmpp_recv->newwin += window_size(agent);
+			spin_unlock_irqrestore(&rmpp_recv->lock, flags);
+			ack_recv(rmpp_recv, mad_recv_wc);
+			goto out;
+		}
+	}
+	spin_unlock_irqrestore(&rmpp_recv->lock, flags);
+out:
+	deref_rmpp_recv(rmpp_recv);
+	return done_wc;
+
+drop3:	spin_unlock_irqrestore(&rmpp_recv->lock, flags);
+drop2:	deref_rmpp_recv(rmpp_recv);
+drop1:	ib_free_recv_mad(mad_recv_wc);
+	return NULL;
+}
+
+static struct ib_mad_recv_wc *
+start_rmpp(struct ib_mad_agent_private *agent,
+	   struct ib_mad_recv_wc *mad_recv_wc)
+{
+	struct mad_rmpp_recv *rmpp_recv;
+	unsigned long flags;
+
+	rmpp_recv = create_rmpp_recv(agent, mad_recv_wc);
+	if (!rmpp_recv) {
+		ib_free_recv_mad(mad_recv_wc);
+		return NULL;
+	}
+
+	spin_lock_irqsave(&agent->lock, flags);
+	if (insert_rmpp_recv(agent, rmpp_recv)) {
+		spin_unlock_irqrestore(&agent->lock, flags);
+		/* duplicate first MAD */
+		destroy_rmpp_recv(rmpp_recv);
+		return continue_rmpp(agent, mad_recv_wc);
+	}
+	atomic_inc(&rmpp_recv->refcount);
+
+	if (get_last_flag(&mad_recv_wc->recv_buf)) {
+		rmpp_recv->state = RMPP_STATE_COMPLETE;
+		spin_unlock_irqrestore(&agent->lock, flags);
+		complete_rmpp(rmpp_recv);
+	} else {
+		spin_unlock_irqrestore(&agent->lock, flags);
+		/* 40 seconds until we can find the packet lifetimes */
+		queue_delayed_work(agent->qp_info->port_priv->wq,
+				   &rmpp_recv->timeout_work,
+				   msecs_to_jiffies(40000));
+		rmpp_recv->newwin += window_size(agent);
+		ack_recv(rmpp_recv, mad_recv_wc);
+		mad_recv_wc = NULL;
+	}
+	deref_rmpp_recv(rmpp_recv);
+	return mad_recv_wc;
+}
+
+static inline u64 get_seg_addr(struct ib_mad_send_wr_private *mad_send_wr)
+{
+	return mad_send_wr->sg_list[0].addr + mad_send_wr->data_offset +
+	       (sizeof(struct ib_rmpp_mad) - mad_send_wr->data_offset) *
+	       (mad_send_wr->seg_num - 1);
+}
+
+static int send_next_seg(struct ib_mad_send_wr_private *mad_send_wr)
+{
+	struct ib_rmpp_mad *rmpp_mad;
+	int timeout;
+
+	rmpp_mad = (struct ib_rmpp_mad *)mad_send_wr->send_wr.wr.ud.mad_hdr;
+	ib_set_rmpp_flags(&rmpp_mad->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
+	rmpp_mad->rmpp_hdr.seg_num = cpu_to_be32(mad_send_wr->seg_num);
+
+	if (mad_send_wr->seg_num == 1) {
+		rmpp_mad->rmpp_hdr.rmpp_rtime_flags |= IB_MGMT_RMPP_FLAG_FIRST;
+		rmpp_mad->rmpp_hdr.paylen_newwin =
+			cpu_to_be32(mad_send_wr->total_seg *
+				    (sizeof(struct ib_rmpp_mad) -
+				       offsetof(struct ib_rmpp_mad, data)));
+		mad_send_wr->sg_list[0].length = sizeof(struct ib_rmpp_mad);
+	} else {
+		mad_send_wr->send_wr.num_sge = 2;
+		mad_send_wr->sg_list[0].length = mad_send_wr->data_offset;
+		mad_send_wr->sg_list[1].addr = get_seg_addr(mad_send_wr);
+		mad_send_wr->sg_list[1].length = sizeof(struct ib_rmpp_mad) -
+						 mad_send_wr->data_offset;
+		mad_send_wr->sg_list[1].lkey = mad_send_wr->sg_list[0].lkey;
+	}
+
+	if (mad_send_wr->seg_num == mad_send_wr->total_seg) {
+		rmpp_mad->rmpp_hdr.rmpp_rtime_flags |= IB_MGMT_RMPP_FLAG_LAST;
+		rmpp_mad->rmpp_hdr.paylen_newwin =
+			cpu_to_be32(sizeof(struct ib_rmpp_mad) -
+				    offsetof(struct ib_rmpp_mad, data) -
+				    mad_send_wr->pad);
+	}
+
+	/* 2 seconds for an ACK until we can find the packet lifetime */
+	timeout = mad_send_wr->send_wr.wr.ud.timeout_ms;
+	if (!timeout || timeout > 2000)
+		mad_send_wr->timeout = msecs_to_jiffies(2000);
+	mad_send_wr->seg_num++;
+	return ib_send_mad(mad_send_wr);
+}
+
+static void process_rmpp_ack(struct ib_mad_agent_private *agent,
+			     struct ib_mad_recv_wc *mad_recv_wc)
+{
+	struct ib_mad_send_wr_private *mad_send_wr;
+	struct ib_rmpp_mad *rmpp_mad;
+	unsigned long flags;
+	int seg_num, newwin, ret;
+
+	rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;
+	if (rmpp_mad->rmpp_hdr.rmpp_status)
+		return;
+
+	seg_num = be32_to_cpu(rmpp_mad->rmpp_hdr.seg_num);
+	newwin = be32_to_cpu(rmpp_mad->rmpp_hdr.paylen_newwin);
+
+	spin_lock_irqsave(&agent->lock, flags);
+	mad_send_wr = ib_find_send_mad(agent, rmpp_mad->mad_hdr.tid);
+	if (!mad_send_wr)
+		goto out;	/* Unmatched ACK */
+
+	if ((mad_send_wr->last_ack == mad_send_wr->total_seg) ||
+	    (!mad_send_wr->timeout) || (mad_send_wr->status != IB_WC_SUCCESS))
+		goto out;	/* Send is already done */
+
+	if (seg_num > mad_send_wr->total_seg)
+		goto out;	/* Bad ACK */
+
+	if (newwin < mad_send_wr->newwin || seg_num < mad_send_wr->last_ack)
+		goto out;	/* Old ACK */
+
+	if (seg_num > mad_send_wr->last_ack) {
+		mad_send_wr->last_ack = seg_num;
+		mad_send_wr->retries = mad_send_wr->send_wr.wr.ud.retries;
+	}
+	mad_send_wr->newwin = newwin;
+	if (mad_send_wr->last_ack == mad_send_wr->total_seg) {
+		/* If no response is expected, the ACK completes the send */
+		if (!mad_send_wr->send_wr.wr.ud.timeout_ms) {
+			struct ib_mad_send_wc wc;
+
+			ib_mark_mad_done(mad_send_wr);
+			spin_unlock_irqrestore(&agent->lock, flags);
+
+			wc.status = IB_WC_SUCCESS;
+			wc.vendor_err = 0;
+			wc.wr_id = mad_send_wr->wr_id;
+			ib_mad_complete_send_wr(mad_send_wr, &wc);
+			return;
+		}
+		if (mad_send_wr->refcount == 1)
+			ib_reset_mad_timeout(mad_send_wr, mad_send_wr->
+					     send_wr.wr.ud.timeout_ms);
+	} else if (mad_send_wr->refcount == 1 &&
+		   mad_send_wr->seg_num < mad_send_wr->newwin &&
+		   mad_send_wr->seg_num <= mad_send_wr->total_seg) {
+		/* Send failure will just result in a timeout/retry */
+		ret = send_next_seg(mad_send_wr);
+		if (ret)
+			goto out;
+
+		mad_send_wr->refcount++;
+		list_del(&mad_send_wr->agent_list);
+		list_add_tail(&mad_send_wr->agent_list,
+			      &mad_send_wr->mad_agent_priv->send_list);
+	}
+out:
+	spin_unlock_irqrestore(&agent->lock, flags);
+}
+
+struct ib_mad_recv_wc *
+ib_process_rmpp_recv_wc(struct ib_mad_agent_private *agent,
+			struct ib_mad_recv_wc *mad_recv_wc)
+{
+	struct ib_rmpp_mad *rmpp_mad;
+
+	rmpp_mad = (struct ib_rmpp_mad *)mad_recv_wc->recv_buf.mad;
+	if (!(rmpp_mad->rmpp_hdr.rmpp_rtime_flags & IB_MGMT_RMPP_FLAG_ACTIVE))
+		return mad_recv_wc;
+
+	if (rmpp_mad->rmpp_hdr.rmpp_version != IB_MGMT_RMPP_VERSION)
+		goto out;
+
+	switch (rmpp_mad->rmpp_hdr.rmpp_type) {
+	case IB_MGMT_RMPP_TYPE_DATA:
+		if (rmpp_mad->rmpp_hdr.seg_num == __constant_htonl(1))
+			return start_rmpp(agent, mad_recv_wc);
+		else
+			return continue_rmpp(agent, mad_recv_wc);
+	case IB_MGMT_RMPP_TYPE_ACK:
+		process_rmpp_ack(agent, mad_recv_wc);
+		break;
+	case IB_MGMT_RMPP_TYPE_STOP:
+	case IB_MGMT_RMPP_TYPE_ABORT:
+		/* TODO: process_rmpp_nack(agent, mad_recv_wc); */
+		break;
+	default:
+		break;
+	}
+out:
+	ib_free_recv_mad(mad_recv_wc);
+	return NULL;
+}
+
+int ib_send_rmpp_mad(struct ib_mad_send_wr_private *mad_send_wr)
+{
+	struct ib_rmpp_mad *rmpp_mad;
+	int i, total_len, ret;
+
+	rmpp_mad = (struct ib_rmpp_mad *)mad_send_wr->send_wr.wr.ud.mad_hdr;
+	if (!(ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
+	      IB_MGMT_RMPP_FLAG_ACTIVE))
+		return IB_RMPP_RESULT_UNHANDLED;
+
+	if (rmpp_mad->rmpp_hdr.rmpp_type != IB_MGMT_RMPP_TYPE_DATA)
+		return IB_RMPP_RESULT_INTERNAL;
+
+	if (mad_send_wr->send_wr.num_sge > 1)
+		return -EINVAL;		/* TODO: support num_sge > 1 */
+
+	mad_send_wr->seg_num = 1;
+	mad_send_wr->newwin = 1;
+	mad_send_wr->data_offset = data_offset(rmpp_mad->mad_hdr.mgmt_class);
+
+	total_len = 0;
+	for (i = 0; i < mad_send_wr->send_wr.num_sge; i++)
+		total_len += mad_send_wr->send_wr.sg_list[i].length;
+
+        mad_send_wr->total_seg = (total_len - mad_send_wr->data_offset) /
+			(sizeof(struct ib_rmpp_mad) - mad_send_wr->data_offset);
+	mad_send_wr->pad = total_len - offsetof(struct ib_rmpp_mad, data) -
+			   be32_to_cpu(rmpp_mad->rmpp_hdr.paylen_newwin);
+
+	/* We need to wait for the final ACK even if there isn't a response */
+	mad_send_wr->refcount += (mad_send_wr->timeout == 0);
+	ret = send_next_seg(mad_send_wr);
+	if (!ret)
+		return IB_RMPP_RESULT_CONSUMED;
+	return ret;
+}
+
+int ib_process_rmpp_send_wc(struct ib_mad_send_wr_private *mad_send_wr,
+			    struct ib_mad_send_wc *mad_send_wc)
+{
+	struct ib_rmpp_mad *rmpp_mad;
+	struct ib_mad_send_buf *msg;
+	int ret;
+
+	rmpp_mad = (struct ib_rmpp_mad *)mad_send_wr->send_wr.wr.ud.mad_hdr;
+	if (!(ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
+	      IB_MGMT_RMPP_FLAG_ACTIVE))
+		return IB_RMPP_RESULT_UNHANDLED; /* RMPP not active */
+
+	if (rmpp_mad->rmpp_hdr.rmpp_type != IB_MGMT_RMPP_TYPE_DATA) {
+		msg = (struct ib_mad_send_buf *) (unsigned long)
+		      mad_send_wc->wr_id;
+		ib_free_send_mad(msg);
+		return IB_RMPP_RESULT_INTERNAL;	 /* ACK, STOP, or ABORT */
+	}
+
+	if (mad_send_wc->status != IB_WC_SUCCESS ||
+	    mad_send_wr->status != IB_WC_SUCCESS)
+		return IB_RMPP_RESULT_PROCESSED; /* Canceled or send error */
+
+	if (!mad_send_wr->timeout)
+		return IB_RMPP_RESULT_PROCESSED; /* Response received */
+
+	if (mad_send_wr->last_ack == mad_send_wr->total_seg) {
+		mad_send_wr->timeout =
+			msecs_to_jiffies(mad_send_wr->send_wr.wr.ud.timeout_ms);
+		return IB_RMPP_RESULT_PROCESSED; /* Send done */
+	}
+
+	if (mad_send_wr->seg_num > mad_send_wr->newwin ||
+	    mad_send_wr->seg_num > mad_send_wr->total_seg)
+		return IB_RMPP_RESULT_PROCESSED; /* Wait for ACK */
+
+	ret = send_next_seg(mad_send_wr);
+	if (ret) {
+		mad_send_wc->status = IB_WC_GENERAL_ERR;
+		return IB_RMPP_RESULT_PROCESSED;
+	}
+	return IB_RMPP_RESULT_CONSUMED;
+}
+
+int ib_retry_rmpp(struct ib_mad_send_wr_private *mad_send_wr)
+{
+	struct ib_rmpp_mad *rmpp_mad;
+	int ret;
+
+	rmpp_mad = (struct ib_rmpp_mad *)mad_send_wr->send_wr.wr.ud.mad_hdr;
+	if (!(ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
+	      IB_MGMT_RMPP_FLAG_ACTIVE))
+		return IB_RMPP_RESULT_UNHANDLED; /* RMPP not active */
+
+	if (mad_send_wr->last_ack == mad_send_wr->total_seg)
+		return IB_RMPP_RESULT_PROCESSED;
+
+	mad_send_wr->seg_num = mad_send_wr->last_ack + 1;
+	ret = send_next_seg(mad_send_wr);
+	if (ret)
+		return IB_RMPP_RESULT_PROCESSED;
+
+	return IB_RMPP_RESULT_CONSUMED;
+}