mad.c

linux-2.6.15.6

	struct ib_mad_list_head		*mad_list;
	struct ib_mad_qp_info		*qp_info;
	struct ib_mad_queue		*send_queue;
	struct ib_send_wr		*bad_send_wr;
	struct ib_mad_send_wc		mad_send_wc;
	unsigned long flags;
	int ret;

	mad_list = (struct ib_mad_list_head *)(unsigned long)wc->wr_id;
	mad_send_wr = container_of(mad_list, struct ib_mad_send_wr_private,
				   mad_list);
	send_queue = mad_list->mad_queue;
	qp_info = send_queue->qp_info;

retry:
	dma_unmap_single(mad_send_wr->send_buf.mad_agent->device->dma_device,
			 pci_unmap_addr(mad_send_wr, mapping),
			 mad_send_wr->sg_list[0].length, DMA_TO_DEVICE);
	queued_send_wr = NULL;
	spin_lock_irqsave(&send_queue->lock, flags);
	list_del(&mad_list->list);

	/* Move queued send to the send queue */
	if (send_queue->count-- > send_queue->max_active) {
		mad_list = container_of(qp_info->overflow_list.next,
					struct ib_mad_list_head, list);
		queued_send_wr = container_of(mad_list,
					struct ib_mad_send_wr_private,
					mad_list);
		list_del(&mad_list->list);
		list_add_tail(&mad_list->list, &send_queue->list);
	}
	spin_unlock_irqrestore(&send_queue->lock, flags);

	mad_send_wc.send_buf = &mad_send_wr->send_buf;
	mad_send_wc.status = wc->status;
	mad_send_wc.vendor_err = wc->vendor_err;
	if (atomic_read(&qp_info->snoop_count))
		snoop_send(qp_info, &mad_send_wr->send_buf, &mad_send_wc,
			   IB_MAD_SNOOP_SEND_COMPLETIONS);
	ib_mad_complete_send_wr(mad_send_wr, &mad_send_wc);

	if (queued_send_wr) {
		ret = ib_post_send(qp_info->qp, &queued_send_wr->send_wr,
				   &bad_send_wr);
		if (ret) {
			printk(KERN_ERR PFX "ib_post_send failed: %d\n", ret);
			mad_send_wr = queued_send_wr;
			wc->status = IB_WC_LOC_QP_OP_ERR;
			goto retry;
		}
	}
}

static void mark_sends_for_retry(struct ib_mad_qp_info *qp_info)
{
	struct ib_mad_send_wr_private *mad_send_wr;
	struct ib_mad_list_head *mad_list;
	unsigned long flags;

	spin_lock_irqsave(&qp_info->send_queue.lock, flags);
	list_for_each_entry(mad_list, &qp_info->send_queue.list, list) {
		mad_send_wr = container_of(mad_list,
					   struct ib_mad_send_wr_private,
					   mad_list);
		mad_send_wr->retry = 1;
	}
	spin_unlock_irqrestore(&qp_info->send_queue.lock, flags);
}

static void mad_error_handler(struct ib_mad_port_private *port_priv,
			      struct ib_wc *wc)
{
	struct ib_mad_list_head *mad_list;
	struct ib_mad_qp_info *qp_info;
	struct ib_mad_send_wr_private *mad_send_wr;
	int ret;

	/* Determine if failure was a send or receive */
	mad_list = (struct ib_mad_list_head *)(unsigned long)wc->wr_id;
	qp_info = mad_list->mad_queue->qp_info;
	if (mad_list->mad_queue == &qp_info->recv_queue)
		/*
		 * Receive errors indicate that the QP has entered the error
		 * state - error handling/shutdown code will cleanup
		 */
		return;

	/*
	 * Send errors will transition the QP to SQE - move
	 * QP to RTS and repost flushed work requests
	 */
	mad_send_wr = container_of(mad_list, struct ib_mad_send_wr_private,
				   mad_list);
	if (wc->status == IB_WC_WR_FLUSH_ERR) {
		if (mad_send_wr->retry) {
			/* Repost send */
			struct ib_send_wr *bad_send_wr;

			mad_send_wr->retry = 0;
			ret = ib_post_send(qp_info->qp, &mad_send_wr->send_wr,
					&bad_send_wr);
			if (ret)
				ib_mad_send_done_handler(port_priv, wc);
		} else
			ib_mad_send_done_handler(port_priv, wc);
	} else {
		struct ib_qp_attr *attr;

		/* Transition QP to RTS and fail offending send */
		attr = kmalloc(sizeof *attr, GFP_KERNEL);
		if (attr) {
			attr->qp_state = IB_QPS_RTS;
			attr->cur_qp_state = IB_QPS_SQE;
			ret = ib_modify_qp(qp_info->qp, attr,
					   IB_QP_STATE | IB_QP_CUR_STATE);
			kfree(attr);
			if (ret)
				printk(KERN_ERR PFX "mad_error_handler - "
				       "ib_modify_qp to RTS : %d\n", ret);
			else
				mark_sends_for_retry(qp_info);
		}
		ib_mad_send_done_handler(port_priv, wc);
	}
}

/*
 * IB MAD completion callback
 */
static void ib_mad_completion_handler(void *data)
{
	struct ib_mad_port_private *port_priv;
	struct ib_wc wc;

	port_priv = (struct ib_mad_port_private *)data;
	ib_req_notify_cq(port_priv->cq, IB_CQ_NEXT_COMP);

	while (ib_poll_cq(port_priv->cq, 1, &wc) == 1) {
		if (wc.status == IB_WC_SUCCESS) {
			switch (wc.opcode) {
			case IB_WC_SEND:
				ib_mad_send_done_handler(port_priv, &wc);
				break;
			case IB_WC_RECV:
				ib_mad_recv_done_handler(port_priv, &wc);
				break;
			default:
				BUG_ON(1);
				break;
			}
		} else
			mad_error_handler(port_priv, &wc);
	}
}

static void cancel_mads(struct ib_mad_agent_private *mad_agent_priv)
{
	unsigned long flags;
	struct ib_mad_send_wr_private *mad_send_wr, *temp_mad_send_wr;
	struct ib_mad_send_wc mad_send_wc;
	struct list_head cancel_list;

	INIT_LIST_HEAD(&cancel_list);

	spin_lock_irqsave(&mad_agent_priv->lock, flags);
	list_for_each_entry_safe(mad_send_wr, temp_mad_send_wr,
				 &mad_agent_priv->send_list, agent_list) {
		if (mad_send_wr->status == IB_WC_SUCCESS) {
 			mad_send_wr->status = IB_WC_WR_FLUSH_ERR;
			mad_send_wr->refcount -= (mad_send_wr->timeout > 0);
		}
	}

	/* Empty wait list to prevent receives from finding a request */
	list_splice_init(&mad_agent_priv->wait_list, &cancel_list);
	/* Empty local completion list as well */
	list_splice_init(&mad_agent_priv->local_list, &cancel_list);
	spin_unlock_irqrestore(&mad_agent_priv->lock, flags);

	/* Report all cancelled requests */
	mad_send_wc.status = IB_WC_WR_FLUSH_ERR;
	mad_send_wc.vendor_err = 0;

	list_for_each_entry_safe(mad_send_wr, temp_mad_send_wr,
				 &cancel_list, agent_list) {
		mad_send_wc.send_buf = &mad_send_wr->send_buf;
		list_del(&mad_send_wr->agent_list);
		mad_agent_priv->agent.send_handler(&mad_agent_priv->agent,
						   &mad_send_wc);
		atomic_dec(&mad_agent_priv->refcount);
	}
}

static struct ib_mad_send_wr_private*
find_send_wr(struct ib_mad_agent_private *mad_agent_priv,
	     struct ib_mad_send_buf *send_buf)
{
	struct ib_mad_send_wr_private *mad_send_wr;

	list_for_each_entry(mad_send_wr, &mad_agent_priv->wait_list,
			    agent_list) {
		if (&mad_send_wr->send_buf == send_buf)
			return mad_send_wr;
	}

	list_for_each_entry(mad_send_wr, &mad_agent_priv->send_list,
			    agent_list) {
		if (is_data_mad(mad_agent_priv, mad_send_wr->send_buf.mad) &&
		    &mad_send_wr->send_buf == send_buf)
			return mad_send_wr;
	}
	return NULL;
}

int ib_modify_mad(struct ib_mad_agent *mad_agent,
		  struct ib_mad_send_buf *send_buf, u32 timeout_ms)
{
	struct ib_mad_agent_private *mad_agent_priv;
	struct ib_mad_send_wr_private *mad_send_wr;
	unsigned long flags;
	int active;

	mad_agent_priv = container_of(mad_agent, struct ib_mad_agent_private,
				      agent);
	spin_lock_irqsave(&mad_agent_priv->lock, flags);
	mad_send_wr = find_send_wr(mad_agent_priv, send_buf);
	if (!mad_send_wr || mad_send_wr->status != IB_WC_SUCCESS) {
		spin_unlock_irqrestore(&mad_agent_priv->lock, flags);
		return -EINVAL;
	}

	active = (!mad_send_wr->timeout || mad_send_wr->refcount > 1);
	if (!timeout_ms) {
		mad_send_wr->status = IB_WC_WR_FLUSH_ERR;
		mad_send_wr->refcount -= (mad_send_wr->timeout > 0);
	}

	mad_send_wr->send_buf.timeout_ms = timeout_ms;
	if (active)
		mad_send_wr->timeout = msecs_to_jiffies(timeout_ms);
	else
		ib_reset_mad_timeout(mad_send_wr, timeout_ms);

	spin_unlock_irqrestore(&mad_agent_priv->lock, flags);
	return 0;
}
EXPORT_SYMBOL(ib_modify_mad);

void ib_cancel_mad(struct ib_mad_agent *mad_agent,
		   struct ib_mad_send_buf *send_buf)
{
	ib_modify_mad(mad_agent, send_buf, 0);
}
EXPORT_SYMBOL(ib_cancel_mad);

static void local_completions(void *data)
{
	struct ib_mad_agent_private *mad_agent_priv;
	struct ib_mad_local_private *local;
	struct ib_mad_agent_private *recv_mad_agent;
	unsigned long flags;
	int recv = 0;
	struct ib_wc wc;
	struct ib_mad_send_wc mad_send_wc;

	mad_agent_priv = (struct ib_mad_agent_private *)data;

	spin_lock_irqsave(&mad_agent_priv->lock, flags);
	while (!list_empty(&mad_agent_priv->local_list)) {
		local = list_entry(mad_agent_priv->local_list.next,
				   struct ib_mad_local_private,
				   completion_list);
		spin_unlock_irqrestore(&mad_agent_priv->lock, flags);
		if (local->mad_priv) {
			recv_mad_agent = local->recv_mad_agent;
			if (!recv_mad_agent) {
				printk(KERN_ERR PFX "No receive MAD agent for local completion\n");
				goto local_send_completion;
			}

			recv = 1;
			/*
			 * Defined behavior is to complete response
			 * before request
			 */
			build_smp_wc((unsigned long) local->mad_send_wr,
				     be16_to_cpu(IB_LID_PERMISSIVE),
				     0, recv_mad_agent->agent.port_num, &wc);

			local->mad_priv->header.recv_wc.wc = &wc;
			local->mad_priv->header.recv_wc.mad_len =
						sizeof(struct ib_mad);
			INIT_LIST_HEAD(&local->mad_priv->header.recv_wc.rmpp_list);
			list_add(&local->mad_priv->header.recv_wc.recv_buf.list,
				 &local->mad_priv->header.recv_wc.rmpp_list);
			local->mad_priv->header.recv_wc.recv_buf.grh = NULL;
			local->mad_priv->header.recv_wc.recv_buf.mad =
						&local->mad_priv->mad.mad;
			if (atomic_read(&recv_mad_agent->qp_info->snoop_count))
				snoop_recv(recv_mad_agent->qp_info,
					  &local->mad_priv->header.recv_wc,
					   IB_MAD_SNOOP_RECVS);
			recv_mad_agent->agent.recv_handler(
						&recv_mad_agent->agent,
						&local->mad_priv->header.recv_wc);
			spin_lock_irqsave(&recv_mad_agent->lock, flags);
			atomic_dec(&recv_mad_agent->refcount);
			spin_unlock_irqrestore(&recv_mad_agent->lock, flags);
		}

local_send_completion:
		/* Complete send */
		mad_send_wc.status = IB_WC_SUCCESS;
		mad_send_wc.vendor_err = 0;
		mad_send_wc.send_buf = &local->mad_send_wr->send_buf;
		if (atomic_read(&mad_agent_priv->qp_info->snoop_count))
			snoop_send(mad_agent_priv->qp_info,
				   &local->mad_send_wr->send_buf,
				   &mad_send_wc, IB_MAD_SNOOP_SEND_COMPLETIONS);
		mad_agent_priv->agent.send_handler(&mad_agent_priv->agent,
						   &mad_send_wc);

		spin_lock_irqsave(&mad_agent_priv->lock, flags);
		list_del(&local->completion_list);
		atomic_dec(&mad_agent_priv->refcount);
		if (!recv)
			kmem_cache_free(ib_mad_cache, local->mad_priv);
		kfree(local);
	}
	spin_unlock_irqrestore(&mad_agent_priv->lock, flags);
}

static int retry_send(struct ib_mad_send_wr_private *mad_send_wr)
{
	int ret;

	if (!mad_send_wr->retries--)
		return -ETIMEDOUT;

	mad_send_wr->timeout = msecs_to_jiffies(mad_send_wr->send_buf.timeout_ms);

	if (mad_send_wr->mad_agent_priv->agent.rmpp_version) {
		ret = ib_retry_rmpp(mad_send_wr);
		switch (ret) {
		case IB_RMPP_RESULT_UNHANDLED:
			ret = ib_send_mad(mad_send_wr);
			break;
		case IB_RMPP_RESULT_CONSUMED:
			ret = 0;
			break;
		default:
			ret = -ECOMM;
			break;
		}
	} else
		ret = ib_send_mad(mad_send_wr);

	if (!ret) {
		mad_send_wr->refcount++;
		list_add_tail(&mad_send_wr->agent_list,
			      &mad_send_wr->mad_agent_priv->send_list);
	}
	return ret;
}

static void timeout_sends(void *data)
{
	struct ib_mad_agent_private *mad_agent_priv;
	struct ib_mad_send_wr_private *mad_send_wr;
	struct ib_mad_send_wc mad_send_wc;
	unsigned long flags, delay;

	mad_agent_priv = (struct ib_mad_agent_private *)data;
	mad_send_wc.vendor_err = 0;

	spin_lock_irqsave(&mad_agent_priv->lock, flags);
	while (!list_empty(&mad_agent_priv->wait_list)) {
		mad_send_wr = list_entry(mad_agent_priv->wait_list.next,
					 struct ib_mad_send_wr_private,
					 agent_list);

		if (time_after(mad_send_wr->timeout, jiffies)) {
			delay = mad_send_wr->timeout - jiffies;
			if ((long)delay <= 0)
				delay = 1;
			queue_delayed_work(mad_agent_priv->qp_info->
					   port_priv->wq,
					   &mad_agent_priv->timed_work, delay);
			break;
		}

		list_del(&mad_send_wr->agent_list);
		if (mad_send_wr->status == IB_WC_SUCCESS &&
		    !retry_send(mad_send_wr))
			continue;

		spin_unlock_irqrestore(&mad_agent_priv->lock, flags);

		if (mad_send_wr->status == IB_WC_SUCCESS)
			mad_send_wc.status = IB_WC_RESP_TIMEOUT_ERR;
		else
			mad_send_wc.status = mad_send_wr->status;
		mad_send_wc.send_buf = &mad_send_wr->send_buf;
		mad_agent_priv->agent.send_handler(&mad_agent_priv->agent,
						   &mad_send_wc);

		atomic_dec(&mad_agent_priv->refcount);
		spin_lock_irqsave(&mad_agent_priv->lock, flags);
	}
	spin_unlock_irqrestore(&mad_agent_priv->lock, flags);
}

static void ib_mad_thread_completion_handler(struct ib_cq *cq, void *arg)
{
	struct ib_mad_port_private *port_priv = cq->cq_context;

	queue_work(port_priv->wq, &port_priv->work);
}

/*
 * Allocate receive MADs and post receive WRs for them
 */
static int ib_mad_post_receive_mads(struct ib_mad_qp_info *qp_info,
				    struct ib_mad_private *mad)
{
	unsigned long flags;
	int post, ret;
	struct ib_mad_private *mad_priv;
	struct ib_sge sg_list;
	struct ib_recv_wr recv_wr, *bad_recv_wr;
	struct ib_mad_queue *recv_queue = &qp_info->recv_queue;

	/* Initialize common scatter list fields */
	sg_list.length = sizeof *mad_priv - sizeof mad_priv->header;
	sg_list.lkey = (*qp_info->port_priv->mr).lkey;

	/* Initialize common receive WR fields */
	recv_wr.next = NULL;
	recv_wr.sg_list = &sg_list;
	recv_wr.num_sge = 1;

	do {
		/* Allocate and map receive buffer */
		if (mad) {
			mad_priv = mad;
			mad = NULL;
		} else {
			mad_priv = kmem_cache_alloc(ib_mad_cache, GFP_KERNEL);
			if (!mad_priv) {
				printk(KERN_ERR PFX "No memory for receive buffer\n");
				ret = -ENOMEM;
				break;
			}
		}
		sg