user_mad.c

来自「linux 内核源代码」· C语言 代码 · 共 1,219 行 · 第 1/3 页

	if (hdr1->grh_present && hdr2->grh_present)
	   return !memcmp(hdr1->gid, hdr2->gid, 16);

	return 0;
}

static int is_duplicate(struct ib_umad_file *file,
			struct ib_umad_packet *packet)
{
	struct ib_umad_packet *sent_packet;
	struct ib_mad_hdr *sent_hdr, *hdr;

	hdr = (struct ib_mad_hdr *) packet->mad.data;
	list_for_each_entry(sent_packet, &file->send_list, list) {
		sent_hdr = (struct ib_mad_hdr *) sent_packet->mad.data;

		if ((hdr->tid != sent_hdr->tid) ||
		    (hdr->mgmt_class != sent_hdr->mgmt_class))
			continue;

		/*
		 * No need to be overly clever here.  If two new operations have
		 * the same TID, reject the second as a duplicate.  This is more
		 * restrictive than required by the spec.
		 */
		if (!ib_response_mad((struct ib_mad *) hdr)) {
			if (!ib_response_mad((struct ib_mad *) sent_hdr))
				return 1;
			continue;
		} else if (!ib_response_mad((struct ib_mad *) sent_hdr))
			continue;

		if (same_destination(&packet->mad.hdr, &sent_packet->mad.hdr))
			return 1;
	}

	return 0;
}

static ssize_t ib_umad_write(struct file *filp, const char __user *buf,
			     size_t count, loff_t *pos)
{
	struct ib_umad_file *file = filp->private_data;
	struct ib_umad_packet *packet;
	struct ib_mad_agent *agent;
	struct ib_ah_attr ah_attr;
	struct ib_ah *ah;
	struct ib_rmpp_mad *rmpp_mad;
	__be64 *tid;
	int ret, data_len, hdr_len, copy_offset, rmpp_active;

	if (count < hdr_size(file) + IB_MGMT_RMPP_HDR)
		return -EINVAL;

	packet = kzalloc(sizeof *packet + IB_MGMT_RMPP_HDR, GFP_KERNEL);
	if (!packet)
		return -ENOMEM;

	if (copy_from_user(&packet->mad, buf, hdr_size(file))) {
		ret = -EFAULT;
		goto err;
	}

	if (packet->mad.hdr.id < 0 ||
	    packet->mad.hdr.id >= IB_UMAD_MAX_AGENTS) {
		ret = -EINVAL;
		goto err;
	}

	buf += hdr_size(file);

	if (copy_from_user(packet->mad.data, buf, IB_MGMT_RMPP_HDR)) {
		ret = -EFAULT;
		goto err;
	}

	down_read(&file->port->mutex);

	agent = __get_agent(file, packet->mad.hdr.id);
	if (!agent) {
		ret = -EINVAL;
		goto err_up;
	}

	memset(&ah_attr, 0, sizeof ah_attr);
	ah_attr.dlid          = be16_to_cpu(packet->mad.hdr.lid);
	ah_attr.sl            = packet->mad.hdr.sl;
	ah_attr.src_path_bits = packet->mad.hdr.path_bits;
	ah_attr.port_num      = file->port->port_num;
	if (packet->mad.hdr.grh_present) {
		ah_attr.ah_flags = IB_AH_GRH;
		memcpy(ah_attr.grh.dgid.raw, packet->mad.hdr.gid, 16);
		ah_attr.grh.sgid_index	   = packet->mad.hdr.gid_index;
		ah_attr.grh.flow_label 	   = be32_to_cpu(packet->mad.hdr.flow_label);
		ah_attr.grh.hop_limit  	   = packet->mad.hdr.hop_limit;
		ah_attr.grh.traffic_class  = packet->mad.hdr.traffic_class;
	}

	ah = ib_create_ah(agent->qp->pd, &ah_attr);
	if (IS_ERR(ah)) {
		ret = PTR_ERR(ah);
		goto err_up;
	}

	rmpp_mad = (struct ib_rmpp_mad *) packet->mad.data;
	hdr_len = ib_get_mad_data_offset(rmpp_mad->mad_hdr.mgmt_class);
	if (!ib_is_mad_class_rmpp(rmpp_mad->mad_hdr.mgmt_class)) {
		copy_offset = IB_MGMT_MAD_HDR;
		rmpp_active = 0;
	} else {
		copy_offset = IB_MGMT_RMPP_HDR;
		rmpp_active = ib_get_rmpp_flags(&rmpp_mad->rmpp_hdr) &
			      IB_MGMT_RMPP_FLAG_ACTIVE;
	}

	data_len = count - hdr_size(file) - hdr_len;
	packet->msg = ib_create_send_mad(agent,
					 be32_to_cpu(packet->mad.hdr.qpn),
					 packet->mad.hdr.pkey_index, rmpp_active,
					 hdr_len, data_len, GFP_KERNEL);
	if (IS_ERR(packet->msg)) {
		ret = PTR_ERR(packet->msg);
		goto err_ah;
	}

	packet->msg->ah 	= ah;
	packet->msg->timeout_ms = packet->mad.hdr.timeout_ms;
	packet->msg->retries 	= packet->mad.hdr.retries;
	packet->msg->context[0] = packet;

	/* Copy MAD header.  Any RMPP header is already in place. */
	memcpy(packet->msg->mad, packet->mad.data, IB_MGMT_MAD_HDR);

	if (!rmpp_active) {
		if (copy_from_user(packet->msg->mad + copy_offset,
				   buf + copy_offset,
				   hdr_len + data_len - copy_offset)) {
			ret = -EFAULT;
			goto err_msg;
		}
	} else {
		ret = copy_rmpp_mad(packet->msg, buf);
		if (ret)
			goto err_msg;
	}

	/*
	 * Set the high-order part of the transaction ID to make MADs from
	 * different agents unique, and allow routing responses back to the
	 * original requestor.
	 */
	if (!ib_response_mad(packet->msg->mad)) {
		tid = &((struct ib_mad_hdr *) packet->msg->mad)->tid;
		*tid = cpu_to_be64(((u64) agent->hi_tid) << 32 |
				   (be64_to_cpup(tid) & 0xffffffff));
		rmpp_mad->mad_hdr.tid = *tid;
	}

	spin_lock_irq(&file->send_lock);
	ret = is_duplicate(file, packet);
	if (!ret)
		list_add_tail(&packet->list, &file->send_list);
	spin_unlock_irq(&file->send_lock);
	if (ret) {
		ret = -EINVAL;
		goto err_msg;
	}

	ret = ib_post_send_mad(packet->msg, NULL);
	if (ret)
		goto err_send;

	up_read(&file->port->mutex);
	return count;

err_send:
	dequeue_send(file, packet);
err_msg:
	ib_free_send_mad(packet->msg);
err_ah:
	ib_destroy_ah(ah);
err_up:
	up_read(&file->port->mutex);
err:
	kfree(packet);
	return ret;
}

static unsigned int ib_umad_poll(struct file *filp, struct poll_table_struct *wait)
{
	struct ib_umad_file *file = filp->private_data;

	/* we will always be able to post a MAD send */
	unsigned int mask = POLLOUT | POLLWRNORM;

	poll_wait(filp, &file->recv_wait, wait);

	if (!list_empty(&file->recv_list))
		mask |= POLLIN | POLLRDNORM;

	return mask;
}

static int ib_umad_reg_agent(struct ib_umad_file *file, void __user *arg,
			     int compat_method_mask)
{
	struct ib_user_mad_reg_req ureq;
	struct ib_mad_reg_req req;
	struct ib_mad_agent *agent;
	int agent_id;
	int ret;

	down_write(&file->port->mutex);

	if (!file->port->ib_dev) {
		ret = -EPIPE;
		goto out;
	}

	if (copy_from_user(&ureq, arg, sizeof ureq)) {
		ret = -EFAULT;
		goto out;
	}

	if (ureq.qpn != 0 && ureq.qpn != 1) {
		ret = -EINVAL;
		goto out;
	}

	for (agent_id = 0; agent_id < IB_UMAD_MAX_AGENTS; ++agent_id)
		if (!__get_agent(file, agent_id))
			goto found;

	ret = -ENOMEM;
	goto out;

found:
	if (ureq.mgmt_class) {
		req.mgmt_class         = ureq.mgmt_class;
		req.mgmt_class_version = ureq.mgmt_class_version;
		memcpy(req.oui, ureq.oui, sizeof req.oui);

		if (compat_method_mask) {
			u32 *umm = (u32 *) ureq.method_mask;
			int i;

			for (i = 0; i < BITS_TO_LONGS(IB_MGMT_MAX_METHODS); ++i)
				req.method_mask[i] =
					umm[i * 2] | ((u64) umm[i * 2 + 1] << 32);
		} else
			memcpy(req.method_mask, ureq.method_mask,
			       sizeof req.method_mask);
	}

	agent = ib_register_mad_agent(file->port->ib_dev, file->port->port_num,
				      ureq.qpn ? IB_QPT_GSI : IB_QPT_SMI,
				      ureq.mgmt_class ? &req : NULL,
				      ureq.rmpp_version,
				      send_handler, recv_handler, file);
	if (IS_ERR(agent)) {
		ret = PTR_ERR(agent);
		goto out;
	}

	if (put_user(agent_id,
		     (u32 __user *) (arg + offsetof(struct ib_user_mad_reg_req, id)))) {
		ret = -EFAULT;
		ib_unregister_mad_agent(agent);
		goto out;
	}

	if (!file->already_used) {
		file->already_used = 1;
		if (!file->use_pkey_index) {
			printk(KERN_WARNING "user_mad: process %s did not enable "
			       "P_Key index support.\n", current->comm);
			printk(KERN_WARNING "user_mad:   Documentation/infiniband/user_mad.txt "
			       "has info on the new ABI.\n");
		}
	}

	file->agent[agent_id] = agent;
	ret = 0;

out:
	up_write(&file->port->mutex);
	return ret;
}

static int ib_umad_unreg_agent(struct ib_umad_file *file, u32 __user *arg)
{
	struct ib_mad_agent *agent = NULL;
	u32 id;
	int ret = 0;

	if (get_user(id, arg))
		return -EFAULT;

	down_write(&file->port->mutex);

	if (id < 0 || id >= IB_UMAD_MAX_AGENTS || !__get_agent(file, id)) {
		ret = -EINVAL;
		goto out;
	}

	agent = file->agent[id];
	file->agent[id] = NULL;

out:
	up_write(&file->port->mutex);

	if (agent)
		ib_unregister_mad_agent(agent);

	return ret;
}

static long ib_umad_enable_pkey(struct ib_umad_file *file)
{
	int ret = 0;

	down_write(&file->port->mutex);
	if (file->already_used)
		ret = -EINVAL;
	else
		file->use_pkey_index = 1;
	up_write(&file->port->mutex);

	return ret;
}

static long ib_umad_ioctl(struct file *filp, unsigned int cmd,
			  unsigned long arg)
{
	switch (cmd) {
	case IB_USER_MAD_REGISTER_AGENT:
		return ib_umad_reg_agent(filp->private_data, (void __user *) arg, 0);
	case IB_USER_MAD_UNREGISTER_AGENT:
		return ib_umad_unreg_agent(filp->private_data, (__u32 __user *) arg);
	case IB_USER_MAD_ENABLE_PKEY:
		return ib_umad_enable_pkey(filp->private_data);
	default:
		return -ENOIOCTLCMD;
	}
}

#ifdef CONFIG_COMPAT
static long ib_umad_compat_ioctl(struct file *filp, unsigned int cmd,
				 unsigned long arg)
{
	switch (cmd) {
	case IB_USER_MAD_REGISTER_AGENT:
		return ib_umad_reg_agent(filp->private_data, compat_ptr(arg), 1);
	case IB_USER_MAD_UNREGISTER_AGENT:
		return ib_umad_unreg_agent(filp->private_data, compat_ptr(arg));
	case IB_USER_MAD_ENABLE_PKEY:
		return ib_umad_enable_pkey(filp->private_data);
	default:
		return -ENOIOCTLCMD;
	}
}
#endif

static int ib_umad_open(struct inode *inode, struct file *filp)
{
	struct ib_umad_port *port;
	struct ib_umad_file *file;
	int ret = 0;

	spin_lock(&port_lock);
	port = umad_port[iminor(inode) - IB_UMAD_MINOR_BASE];
	if (port)
		kref_get(&port->umad_dev->ref);
	spin_unlock(&port_lock);

	if (!port)
		return -ENXIO;

	down_write(&port->mutex);

	if (!port->ib_dev) {
		ret = -ENXIO;
		goto out;
	}

	file = kzalloc(sizeof *file, GFP_KERNEL);
	if (!file) {
		kref_put(&port->umad_dev->ref, ib_umad_release_dev);
		ret = -ENOMEM;
		goto out;
	}

	spin_lock_init(&file->recv_lock);
	spin_lock_init(&file->send_lock);
	INIT_LIST_HEAD(&file->recv_list);
	INIT_LIST_HEAD(&file->send_list);
	init_waitqueue_head(&file->recv_wait);

	file->port = port;
	filp->private_data = file;

	list_add_tail(&file->port_list, &port->file_list);

out:
	up_write(&port->mutex);
	return ret;
}