core-cdev.c

		payload += u.packet.payload_length;
		count++;
	}

	a->size    -= uptr_to_u64(p) - a->packets;
	a->packets  = uptr_to_u64(p);
	a->data     = client->vm_start + payload;

	return count;
}

static int ioctl_start_iso(struct client *client, union ioctl_arg *arg)
{
	struct fw_cdev_start_iso *a = &arg->start_iso;

	if (client->iso_context == NULL || a->handle != 0)
		return -EINVAL;

	if (client->iso_context->type == FW_ISO_CONTEXT_RECEIVE &&
	    (a->tags == 0 || a->tags > 15 || a->sync > 15))
		return -EINVAL;

	return fw_iso_context_start(client->iso_context,
				    a->cycle, a->sync, a->tags);
}

static int ioctl_stop_iso(struct client *client, union ioctl_arg *arg)
{
	struct fw_cdev_stop_iso *a = &arg->stop_iso;

	if (client->iso_context == NULL || a->handle != 0)
		return -EINVAL;

	return fw_iso_context_stop(client->iso_context);
}

static int ioctl_get_cycle_timer2(struct client *client, union ioctl_arg *arg)
{
	struct fw_cdev_get_cycle_timer2 *a = &arg->get_cycle_timer2;
	struct fw_card *card = client->device->card;
	struct timespec ts = {0, 0};
	u32 cycle_time;
	int ret = 0;

	local_irq_disable();

	cycle_time = card->driver->read_csr_reg(card, CSR_CYCLE_TIME);

	switch (a->clk_id) {
	case CLOCK_REALTIME:      getnstimeofday(&ts);                   break;
	case CLOCK_MONOTONIC:     do_posix_clock_monotonic_gettime(&ts); break;
	case CLOCK_MONOTONIC_RAW: getrawmonotonic(&ts);                  break;
	default:
		ret = -EINVAL;
	}

	local_irq_enable();

	a->tv_sec      = ts.tv_sec;
	a->tv_nsec     = ts.tv_nsec;
	a->cycle_timer = cycle_time;

	return ret;
}

static int ioctl_get_cycle_timer(struct client *client, union ioctl_arg *arg)
{
	struct fw_cdev_get_cycle_timer *a = &arg->get_cycle_timer;
	struct fw_cdev_get_cycle_timer2 ct2;

	ct2.clk_id = CLOCK_REALTIME;
	ioctl_get_cycle_timer2(client, (union ioctl_arg *)&ct2);

	a->local_time = ct2.tv_sec * USEC_PER_SEC + ct2.tv_nsec / NSEC_PER_USEC;
	a->cycle_timer = ct2.cycle_timer;

	return 0;
}

static void iso_resource_work(struct work_struct *work)
{
	struct iso_resource_event *e;
	struct iso_resource *r =
			container_of(work, struct iso_resource, work.work);
	struct client *client = r->client;
	int generation, channel, bandwidth, todo;
	bool skip, free, success;

	spin_lock_irq(&client->lock);
	generation = client->device->generation;
	todo = r->todo;
	/* Allow 1000ms grace period for other reallocations. */
	if (todo == ISO_RES_ALLOC &&
	    time_is_after_jiffies(client->device->card->reset_jiffies + HZ)) {
		schedule_iso_resource(r, DIV_ROUND_UP(HZ, 3));
		skip = true;
	} else {
		/* We could be called twice within the same generation. */
		skip = todo == ISO_RES_REALLOC &&
		       r->generation == generation;
	}
	free = todo == ISO_RES_DEALLOC ||
	       todo == ISO_RES_ALLOC_ONCE ||
	       todo == ISO_RES_DEALLOC_ONCE;
	r->generation = generation;
	spin_unlock_irq(&client->lock);

	if (skip)
		goto out;

	bandwidth = r->bandwidth;

	fw_iso_resource_manage(client->device->card, generation,
			r->channels, &channel, &bandwidth,
			todo == ISO_RES_ALLOC ||
			todo == ISO_RES_REALLOC ||
			todo == ISO_RES_ALLOC_ONCE,
			r->transaction_data);
	/*
	 * Is this generation outdated already?  As long as this resource sticks
	 * in the idr, it will be scheduled again for a newer generation or at
	 * shutdown.
	 */
	if (channel == -EAGAIN &&
	    (todo == ISO_RES_ALLOC || todo == ISO_RES_REALLOC))
		goto out;

	success = channel >= 0 || bandwidth > 0;

	spin_lock_irq(&client->lock);
	/*
	 * Transit from allocation to reallocation, except if the client
	 * requested deallocation in the meantime.
	 */
	if (r->todo == ISO_RES_ALLOC)
		r->todo = ISO_RES_REALLOC;
	/*
	 * Allocation or reallocation failure?  Pull this resource out of the
	 * idr and prepare for deletion, unless the client is shutting down.
	 */
	if (r->todo == ISO_RES_REALLOC && !success &&
	    !client->in_shutdown &&
	    idr_find(&client->resource_idr, r->resource.handle)) {
		idr_remove(&client->resource_idr, r->resource.handle);
		client_put(client);
		free = true;
	}
	spin_unlock_irq(&client->lock);

	if (todo == ISO_RES_ALLOC && channel >= 0)
		r->channels = 1ULL << channel;

	if (todo == ISO_RES_REALLOC && success)
		goto out;

	if (todo == ISO_RES_ALLOC || todo == ISO_RES_ALLOC_ONCE) {
		e = r->e_alloc;
		r->e_alloc = NULL;
	} else {
		e = r->e_dealloc;
		r->e_dealloc = NULL;
	}
	e->iso_resource.handle    = r->resource.handle;
	e->iso_resource.channel   = channel;
	e->iso_resource.bandwidth = bandwidth;

	queue_event(client, &e->event,
		    &e->iso_resource, sizeof(e->iso_resource), NULL, 0);

	if (free) {
		cancel_delayed_work(&r->work);
		kfree(r->e_alloc);
		kfree(r->e_dealloc);
		kfree(r);
	}
 out:
	client_put(client);
}

static void release_iso_resource(struct client *client,
				 struct client_resource *resource)
{
	struct iso_resource *r =
		container_of(resource, struct iso_resource, resource);

	spin_lock_irq(&client->lock);
	r->todo = ISO_RES_DEALLOC;
	schedule_iso_resource(r, 0);
	spin_unlock_irq(&client->lock);
}

static int init_iso_resource(struct client *client,
		struct fw_cdev_allocate_iso_resource *request, int todo)
{
	struct iso_resource_event *e1, *e2;
	struct iso_resource *r;
	int ret;

	if ((request->channels == 0 && request->bandwidth == 0) ||
	    request->bandwidth > BANDWIDTH_AVAILABLE_INITIAL ||
	    request->bandwidth < 0)
		return -EINVAL;

	r  = kmalloc(sizeof(*r), GFP_KERNEL);
	e1 = kmalloc(sizeof(*e1), GFP_KERNEL);
	e2 = kmalloc(sizeof(*e2), GFP_KERNEL);
	if (r == NULL || e1 == NULL || e2 == NULL) {
		ret = -ENOMEM;
		goto fail;
	}

	INIT_DELAYED_WORK(&r->work, iso_resource_work);
	r->client	= client;
	r->todo		= todo;
	r->generation	= -1;
	r->channels	= request->channels;
	r->bandwidth	= request->bandwidth;
	r->e_alloc	= e1;
	r->e_dealloc	= e2;

	e1->iso_resource.closure = request->closure;
	e1->iso_resource.type    = FW_CDEV_EVENT_ISO_RESOURCE_ALLOCATED;
	e2->iso_resource.closure = request->closure;
	e2->iso_resource.type    = FW_CDEV_EVENT_ISO_RESOURCE_DEALLOCATED;

	if (todo == ISO_RES_ALLOC) {
		r->resource.release = release_iso_resource;
		ret = add_client_resource(client, &r->resource, GFP_KERNEL);
		if (ret < 0)
			goto fail;
	} else {
		r->resource.release = NULL;
		r->resource.handle = -1;
		schedule_iso_resource(r, 0);
	}
	request->handle = r->resource.handle;

	return 0;
 fail:
	kfree(r);
	kfree(e1);
	kfree(e2);

	return ret;
}

static int ioctl_allocate_iso_resource(struct client *client,
				       union ioctl_arg *arg)
{
	return init_iso_resource(client,
			&arg->allocate_iso_resource, ISO_RES_ALLOC);
}

static int ioctl_deallocate_iso_resource(struct client *client,
					 union ioctl_arg *arg)
{
	return release_client_resource(client,
			arg->deallocate.handle, release_iso_resource, NULL);
}

static int ioctl_allocate_iso_resource_once(struct client *client,
					    union ioctl_arg *arg)
{
	return init_iso_resource(client,
			&arg->allocate_iso_resource, ISO_RES_ALLOC_ONCE);
}

static int ioctl_deallocate_iso_resource_once(struct client *client,
					      union ioctl_arg *arg)
{
	return init_iso_resource(client,
			&arg->allocate_iso_resource, ISO_RES_DEALLOC_ONCE);
}

/*
 * Returns a speed code:  Maximum speed to or from this device,
 * limited by the device's link speed, the local node's link speed,
 * and all PHY port speeds between the two links.
 */
static int ioctl_get_speed(struct client *client, union ioctl_arg *arg)
{
	return client->device->max_speed;
}

static int ioctl_send_broadcast_request(struct client *client,
					union ioctl_arg *arg)
{
	struct fw_cdev_send_request *a = &arg->send_request;

	switch (a->tcode) {
	case TCODE_WRITE_QUADLET_REQUEST:
	case TCODE_WRITE_BLOCK_REQUEST:
		break;
	default:
		return -EINVAL;
	}

	/* Security policy: Only allow accesses to Units Space. */
	if (a->offset < CSR_REGISTER_BASE + CSR_CONFIG_ROM_END)
		return -EACCES;

	return init_request(client, a, LOCAL_BUS | 0x3f, SCODE_100);
}

static int ioctl_send_stream_packet(struct client *client, union ioctl_arg *arg)
{
	struct fw_cdev_send_stream_packet *a = &arg->send_stream_packet;
	struct fw_cdev_send_request request;
	int dest;

	if (a->speed > client->device->card->link_speed ||
	    a->length > 1024 << a->speed)
		return -EIO;

	if (a->tag > 3 || a->channel > 63 || a->sy > 15)
		return -EINVAL;

	dest = fw_stream_packet_destination_id(a->tag, a->channel, a->sy);
	request.tcode		= TCODE_STREAM_DATA;
	request.length		= a->length;
	request.closure		= a->closure;
	request.data		= a->data;
	request.generation	= a->generation;

	return init_request(client, &request, dest, a->speed);
}

static int (* const ioctl_handlers[])(struct client *, union ioctl_arg *) = {
	ioctl_get_info,
	ioctl_send_request,
	ioctl_allocate,
	ioctl_deallocate,
	ioctl_send_response,
	ioctl_initiate_bus_reset,
	ioctl_add_descriptor,
	ioctl_remove_descriptor,
	ioctl_create_iso_context,
	ioctl_queue_iso,
	ioctl_start_iso,
	ioctl_stop_iso,
	ioctl_get_cycle_timer,
	ioctl_allocate_iso_resource,
	ioctl_deallocate_iso_resource,
	ioctl_allocate_iso_resource_once,
	ioctl_deallocate_iso_resource_once,
	ioctl_get_speed,
	ioctl_send_broadcast_request,
	ioctl_send_stream_packet,
	ioctl_get_cycle_timer2,
};

static int dispatch_ioctl(struct client *client,
			  unsigned int cmd, void __user *arg)
{
	union ioctl_arg buffer;
	int ret;

	if (fw_device_is_shutdown(client->device))
		return -ENODEV;

	if (_IOC_TYPE(cmd) != '#' ||
	    _IOC_NR(cmd) >= ARRAY_SIZE(ioctl_handlers) ||
	    _IOC_SIZE(cmd) > sizeof(buffer))
		return -EINVAL;

	if (_IOC_DIR(cmd) == _IOC_READ)
		memset(&buffer, 0, _IOC_SIZE(cmd));

	if (_IOC_DIR(cmd) & _IOC_WRITE)
		if (copy_from_user(&buffer, arg, _IOC_SIZE(cmd)))
			return -EFAULT;

	ret = ioctl_handlers[_IOC_NR(cmd)](client, &buffer);
	if (ret < 0)
		return ret;

	if (_IOC_DIR(cmd) & _IOC_READ)
		if (copy_to_user(arg, &buffer, _IOC_SIZE(cmd)))
			return -EFAULT;

	return ret;
}

static long fw_device_op_ioctl(struct file *file,
			       unsigned int cmd, unsigned long arg)
{
	return dispatch_ioctl(file->private_data, cmd, (void __user *)arg);
}

#ifdef CONFIG_COMPAT
static long fw_device_op_compat_ioctl(struct file *file,
				      unsigned int cmd, unsigned long arg)
{
	return dispatch_ioctl(file->private_data, cmd, compat_ptr(arg));
}
#endif

static int fw_device_op_mmap(struct file *file, struct vm_area_struct *vma)
{
	struct client *client = file->private_data;
	enum dma_data_direction direction;
	unsigned long size;
	int page_count, ret;

	if (fw_device_is_shutdown(client->device))
		return -ENODEV;

	/* FIXME: We could support multiple buffers, but we don't. */
	if (client->buffer.pages != NULL)
		return -EBUSY;

	if (!(vma->vm_flags & VM_SHARED))
		return -EINVAL;

	if (vma->vm_start & ~PAGE_MASK)
		return -EINVAL;

	client->vm_start = vma->vm_start;
	size = vma->vm_end - vma->vm_start;
	page_count = size >> PAGE_SHIFT;
	if (size & ~PAGE_MASK)
		return -EINVAL;

	if (vma->vm_flags & VM_WRITE)
		direction = DMA_TO_DEVICE;
	else
		direction = DMA_FROM_DEVICE;

	ret = fw_iso_buffer_init(&client->buffer, client->device->card,
				 page_count, direction);
	if (ret < 0)
		return ret;

	ret = fw_iso_buffer_map(&client->buffer, vma);
	if (ret < 0)
		fw_iso_buffer_destroy(&client->buffer, client->device->card);

	return ret;
}

static int shutdown_resource(int id, void *p, void *data)
{
	struct client_resource *resource = p;
	struct client *client = data;

	resource->release(client, resource);
	client_put(client);

	return 0;
}

static int fw_device_op_release(struct inode *inode, struct file *file)
{
	struct client *client = file->private_data;
	struct event *event, *next_event;

	mutex_lock(&client->device->client_list_mutex);
	list_del(&client->link);
	mutex_unlock(&client->device->client_list_mutex);

	if (client->iso_context)
		fw_iso_context_destroy(client->iso_context);

	if (client->buffer.pages)
		fw_iso_buffer_destroy(&client->buffer, client->device->card);

	/* Freeze client->resource_idr and client->event_list */
	spin_lock_irq(&client->lock);
	client->in_shutdown = true;
	spin_unlock_irq(&client->lock);

	idr_for_each(&client->resource_idr, shutdown_resource, client);
	idr_remove_all(&client->resource_idr);
	idr_destroy(&client->resource_idr);

	list_for_each_entry_safe(event, next_event, &client->event_list, link)
		kfree(event);

	client_put(client);

	return 0;
}

static unsigned int fw_device_op_poll(struct file *file, poll_table * pt)
{
	struct client *client = file->private_data;
	unsigned int mask = 0;

	poll_wait(file, &client->wait, pt);

	if (fw_device_is_shutdown(client->device))
		mask |= POLLHUP | POLLERR;
	if (!list_empty(&client->event_list))
		mask |= POLLIN | POLLRDNORM;

	return mask;
}

const struct file_operations fw_device_ops = {
	.owner		= THIS_MODULE,
	.llseek		= no_llseek,
	.open		= fw_device_op_open,
	.read		= fw_device_op_read,
	.unlocked_ioctl	= fw_device_op_ioctl,
	.mmap		= fw_device_op_mmap,
	.release	= fw_device_op_release,
	.poll		= fw_device_op_poll,
#ifdef CONFIG_COMPAT
	.compat_ioctl	= fw_device_op_compat_ioctl,
#endif
};