mad_rmpp.c

linux-2.6.15.6

/*
 * 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;

	__be64 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 int data_offset(u8 mgmt_class)
{
	if (mgmt_class == IB_MGMT_CLASS_SUBN_ADM)
		return IB_MGMT_SA_HDR;
	else if ((mgmt_class >= IB_MGMT_CLASS_VENDOR_RANGE2_START) &&
		 (mgmt_class <= IB_MGMT_CLASS_VENDOR_RANGE2_END))
		return IB_MGMT_VENDOR_HDR;
	else
		return IB_MGMT_RMPP_HDR;
}

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;
	int ret;

	msg = ib_create_send_mad(&rmpp_recv->agent->agent, recv_wc->wc->src_qp,
				 recv_wc->wc->pkey_index, 1, IB_MGMT_RMPP_HDR,
				 IB_MGMT_RMPP_DATA, GFP_KERNEL);
	if (!msg)
		return;

	format_ack(msg->mad, (struct ib_rmpp_mad *) recv_wc->recv_buf.mad,
		   rmpp_recv);
	msg->ah = rmpp_recv->ah;
	ret = ib_post_send_mad(msg, NULL);
	if (ret)
		ib_free_send_mad(msg);
}

static struct ib_mad_send_buf *alloc_response_msg(struct ib_mad_agent *agent,
						  struct ib_mad_recv_wc *recv_wc)
{
	struct ib_mad_send_buf *msg;
	struct ib_ah *ah;

	ah = ib_create_ah_from_wc(agent->qp->pd, recv_wc->wc,
				  recv_wc->recv_buf.grh, agent->port_num);
	if (IS_ERR(ah))
		return (void *) ah;

	msg = ib_create_send_mad(agent, recv_wc->wc->src_qp,
				 recv_wc->wc->pkey_index, 1,
				 IB_MGMT_RMPP_HDR, IB_MGMT_RMPP_DATA,
				 GFP_KERNEL);
	if (IS_ERR(msg))
		ib_destroy_ah(ah);
	else
		msg->ah = ah;

	return msg;
}

void ib_rmpp_send_handler(struct ib_mad_send_wc *mad_send_wc)
{
	struct ib_rmpp_mad *rmpp_mad = mad_send_wc->send_buf->mad;

	if (rmpp_mad->rmpp_hdr.rmpp_type != IB_MGMT_RMPP_TYPE_ACK)
		ib_destroy_ah(mad_send_wc->send_buf->ah);
	ib_free_send_mad(mad_send_wc->send_buf);
}

static void nack_recv(struct ib_mad_agent_private *agent,
		      struct ib_mad_recv_wc *recv_wc, u8 rmpp_status)
{
	struct ib_mad_send_buf *msg;
	struct ib_rmpp_mad *rmpp_mad;
	int ret;

	msg = alloc_response_msg(&agent->agent, recv_wc);
	if (IS_ERR(msg))
		return;

	rmpp_mad = msg->mad;
	memcpy(rmpp_mad, recv_wc->recv_buf.mad,
	       data_offset(recv_wc->recv_buf.mad->mad_hdr.mgmt_class));

	rmpp_mad->mad_hdr.method ^= IB_MGMT_METHOD_RESP;
	rmpp_mad->rmpp_hdr.rmpp_version = IB_MGMT_RMPP_VERSION;
	rmpp_mad->rmpp_hdr.rmpp_type = IB_MGMT_RMPP_TYPE_ABORT;
	ib_set_rmpp_flags(&rmpp_mad->rmpp_hdr, IB_MGMT_RMPP_FLAG_ACTIVE);
	rmpp_mad->rmpp_hdr.rmpp_status = rmpp_status;
	rmpp_mad->rmpp_hdr.seg_num = 0;
	rmpp_mad->rmpp_hdr.paylen_newwin = 0;

	ret = ib_post_send_mad(msg, NULL);
	if (ret) {
		ib_destroy_ah(msg->ah);
		ib_free_send_mad(msg);
	}
}

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);

	rmpp_wc = rmpp_recv->rmpp_wc;
	nack_recv(rmpp_recv->agent, rmpp_wc, IB_MGMT_RMPP_STATUS_T2L);
	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 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 = IB_MGMT_RMPP_DATA - be32_to_cpu(rmpp_mad->rmpp_hdr.paylen_newwin);
	if (pad > IB_MGMT_RMPP_DATA || 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);