[PATCH v3 3/5] staging: vchiq: Move vchiq char driver to its own file

[Ojaswin Mujoo]

Split the initialization code of vchiq char driver and device files from
that of vchiq platform. The char driver code now resides in vchiq_dev.c
and the platform code resides in the original vchiq_arm.c file.

This commit focuses on separating the code into different files while
maintaining the same functionality. It does not completely decouple them
as the cdev init code is still called from the platform's vchiq_probe()
function.

Signed-off-by: Ojaswin Mujoo <ojaswin98@xxxxxxxxx>
---
 drivers/staging/vc04_services/Makefile        |    1 +
 .../interface/vchiq_arm/vchiq_arm.c           | 1619 +----------------
 .../interface/vchiq_arm/vchiq_dev.c           | 1440 +++++++++++++++
 3 files changed, 1540 insertions(+), 1520 deletions(-)
 create mode 100644 drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c

diff --git a/drivers/staging/vc04_services/Makefile b/drivers/staging/vc04_services/Makefile
index e21e73ae3cc6..db28be341239 100644
--- a/drivers/staging/vc04_services/Makefile
+++ b/drivers/staging/vc04_services/Makefile
@@ -7,6 +7,7 @@ vchiq-objs := \
    interface/vchiq_arm/vchiq_2835_arm.o \
    interface/vchiq_arm/vchiq_debugfs.o \
    interface/vchiq_arm/vchiq_connected.o \
+   interface/vchiq_arm/vchiq_dev.o \
 
 obj-$(CONFIG_SND_BCM2835)		+= bcm2835-audio/
 obj-$(CONFIG_VIDEO_BCM2835)		+= bcm2835-camera/
diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
index 3152466086f3..0f2de571eba7 100644
--- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
@@ -48,9 +48,6 @@ int vchiq_susp_log_level = VCHIQ_LOG_ERROR;
 DEFINE_SPINLOCK(msg_queue_spinlock);
 struct vchiq_state g_state;
 
-static struct cdev    vchiq_cdev;
-static dev_t          vchiq_devid;
-static struct class  *vchiq_class;
 static struct platform_device *bcm2835_camera;
 static struct platform_device *bcm2835_audio;
 
@@ -62,29 +59,6 @@ static struct vchiq_drvdata bcm2836_drvdata = {
 	.cache_line_size = 64,
 };
 
-static const char *const ioctl_names[] = {
-	"CONNECT",
-	"SHUTDOWN",
-	"CREATE_SERVICE",
-	"REMOVE_SERVICE",
-	"QUEUE_MESSAGE",
-	"QUEUE_BULK_TRANSMIT",
-	"QUEUE_BULK_RECEIVE",
-	"AWAIT_COMPLETION",
-	"DEQUEUE_MESSAGE",
-	"GET_CLIENT_ID",
-	"GET_CONFIG",
-	"CLOSE_SERVICE",
-	"USE_SERVICE",
-	"RELEASE_SERVICE",
-	"SET_SERVICE_OPTION",
-	"DUMP_PHYS_MEM",
-	"LIB_VERSION",
-	"CLOSE_DELIVERED"
-};
-
-static_assert(ARRAY_SIZE(ioctl_names) == (VCHIQ_IOC_MAX + 1));
-
 static enum vchiq_status
 vchiq_blocking_bulk_transfer(unsigned int handle, void *data,
 	unsigned int size, enum vchiq_bulk_dir dir);
@@ -616,1543 +590,148 @@ service_callback(enum vchiq_reason reason, struct vchiq_header *header,
 		bulk_userdata);
 }
 
-static void
-user_service_free(void *userdata)
-{
-	kfree(userdata);
-}
-
-static void close_delivered(struct user_service *user_service)
-{
-	vchiq_log_info(vchiq_arm_log_level,
-		"%s(handle=%x)",
-		__func__, user_service->service->handle);
-
-	if (user_service->close_pending) {
-		/* Allow the underlying service to be culled */
-		vchiq_service_put(user_service->service);
-
-		/* Wake the user-thread blocked in close_ or remove_service */
-		complete(&user_service->close_event);
-
-		user_service->close_pending = 0;
-	}
-}
-
-struct vchiq_io_copy_callback_context {
-	struct vchiq_element *element;
-	size_t element_offset;
-	unsigned long elements_to_go;
-};
-
-static ssize_t vchiq_ioc_copy_element_data(void *context, void *dest,
-					   size_t offset, size_t maxsize)
+int vchiq_dump(void *dump_context, const char *str, int len)
 {
-	struct vchiq_io_copy_callback_context *cc = context;
-	size_t total_bytes_copied = 0;
-	size_t bytes_this_round;
-
-	while (total_bytes_copied < maxsize) {
-		if (!cc->elements_to_go)
-			return total_bytes_copied;
-
-		if (!cc->element->size) {
-			cc->elements_to_go--;
-			cc->element++;
-			cc->element_offset = 0;
-			continue;
-		}
-
-		bytes_this_round = min(cc->element->size - cc->element_offset,
-				       maxsize - total_bytes_copied);
+	struct dump_context *context = (struct dump_context *)dump_context;
+	int copy_bytes;
 
-		if (copy_from_user(dest + total_bytes_copied,
-				  cc->element->data + cc->element_offset,
-				  bytes_this_round))
-			return -EFAULT;
+	if (context->actual >= context->space)
+		return 0;
 
-		cc->element_offset += bytes_this_round;
-		total_bytes_copied += bytes_this_round;
+	if (context->offset > 0) {
+		int skip_bytes = min_t(int, len, context->offset);
 
-		if (cc->element_offset == cc->element->size) {
-			cc->elements_to_go--;
-			cc->element++;
-			cc->element_offset = 0;
-		}
+		str += skip_bytes;
+		len -= skip_bytes;
+		context->offset -= skip_bytes;
+		if (context->offset > 0)
+			return 0;
 	}
+	copy_bytes = min_t(int, len, context->space - context->actual);
+	if (copy_bytes == 0)
+		return 0;
+	if (copy_to_user(context->buf + context->actual, str,
+			 copy_bytes))
+		return -EFAULT;
+	context->actual += copy_bytes;
+	len -= copy_bytes;
 
-	return maxsize;
-}
-
-static int
-vchiq_ioc_queue_message(unsigned int handle, struct vchiq_element *elements,
-			unsigned long count)
-{
-	struct vchiq_io_copy_callback_context context;
-	enum vchiq_status status = VCHIQ_SUCCESS;
-	unsigned long i;
-	size_t total_size = 0;
-
-	context.element = elements;
-	context.element_offset = 0;
-	context.elements_to_go = count;
+	/*
+	 * If the terminating NUL is included in the length, then it
+	 * marks the end of a line and should be replaced with a
+	 * carriage return.
+	 */
+	if ((len == 0) && (str[copy_bytes - 1] == '\0')) {
+		char cr = '\n';
 
-	for (i = 0; i < count; i++) {
-		if (!elements[i].data && elements[i].size != 0)
+		if (copy_to_user(context->buf + context->actual - 1,
+				 &cr, 1))
 			return -EFAULT;
-
-		total_size += elements[i].size;
-	}
-
-	status = vchiq_queue_message(handle, vchiq_ioc_copy_element_data,
-				     &context, total_size);
-
-	if (status == VCHIQ_ERROR)
-		return -EIO;
-	else if (status == VCHIQ_RETRY)
-		return -EINTR;
-	return 0;
-}
-
-static int vchiq_ioc_create_service(struct vchiq_instance *instance,
-				    struct vchiq_create_service *args)
-{
-	struct user_service *user_service = NULL;
-	struct vchiq_service *service;
-	enum vchiq_status status = VCHIQ_SUCCESS;
-	struct vchiq_service_params_kernel params;
-	int srvstate;
-
-	user_service = kmalloc(sizeof(*user_service), GFP_KERNEL);
-	if (!user_service)
-		return -ENOMEM;
-
-	if (args->is_open) {
-		if (!instance->connected) {
-			kfree(user_service);
-			return -ENOTCONN;
-		}
-		srvstate = VCHIQ_SRVSTATE_OPENING;
-	} else {
-		srvstate = instance->connected ?
-			 VCHIQ_SRVSTATE_LISTENING : VCHIQ_SRVSTATE_HIDDEN;
-	}
-
-	params = (struct vchiq_service_params_kernel) {
-		.fourcc   = args->params.fourcc,
-		.callback = service_callback,
-		.userdata = user_service,
-		.version  = args->params.version,
-		.version_min = args->params.version_min,
-	};
-	service = vchiq_add_service_internal(instance->state, &params,
-					     srvstate, instance,
-					     user_service_free);
-	if (!service) {
-		kfree(user_service);
-		return -EEXIST;
-	}
-
-	user_service->service = service;
-	user_service->userdata = args->params.userdata;
-	user_service->instance = instance;
-	user_service->is_vchi = (args->is_vchi != 0);
-	user_service->dequeue_pending = 0;
-	user_service->close_pending = 0;
-	user_service->message_available_pos = instance->completion_remove - 1;
-	user_service->msg_insert = 0;
-	user_service->msg_remove = 0;
-	init_completion(&user_service->insert_event);
-	init_completion(&user_service->remove_event);
-	init_completion(&user_service->close_event);
-
-	if (args->is_open) {
-		status = vchiq_open_service_internal(service, instance->pid);
-		if (status != VCHIQ_SUCCESS) {
-			vchiq_remove_service(service->handle);
-			return (status == VCHIQ_RETRY) ?
-				-EINTR : -EIO;
-		}
 	}
-	args->handle = service->handle;
-
 	return 0;
 }
 
-static int vchiq_ioc_dequeue_message(struct vchiq_instance *instance,
-				     struct vchiq_dequeue_message *args)
+int vchiq_dump_platform_instances(void *dump_context)
 {
-	struct user_service *user_service;
-	struct vchiq_service *service;
-	struct vchiq_header *header;
-	int ret;
-
-	DEBUG_INITIALISE(g_state.local)
-	DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
-	service = find_service_for_instance(instance, args->handle);
-	if (!service)
-		return -EINVAL;
-
-	user_service = (struct user_service *)service->base.userdata;
-	if (user_service->is_vchi == 0) {
-		ret = -EINVAL;
-		goto out;
-	}
-
-	spin_lock(&msg_queue_spinlock);
-	if (user_service->msg_remove == user_service->msg_insert) {
-		if (!args->blocking) {
-			spin_unlock(&msg_queue_spinlock);
-			DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
-			ret = -EWOULDBLOCK;
-			goto out;
-		}
-		user_service->dequeue_pending = 1;
-		ret = 0;
-		do {
-			spin_unlock(&msg_queue_spinlock);
-			DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
-			if (wait_for_completion_interruptible(
-				&user_service->insert_event)) {
-				vchiq_log_info(vchiq_arm_log_level,
-					"DEQUEUE_MESSAGE interrupted");
-				ret = -EINTR;
-				break;
-			}
-			spin_lock(&msg_queue_spinlock);
-		} while (user_service->msg_remove == user_service->msg_insert);
+	struct vchiq_state *state = vchiq_get_state();
+	char buf[80];
+	int len;
+	int i;
 
-		if (ret)
-			goto out;
-	}
+	/*
+	 * There is no list of instances, so instead scan all services,
+	 * marking those that have been dumped.
+	 */
 
-	if (WARN_ON_ONCE((int)(user_service->msg_insert -
-			 user_service->msg_remove) < 0)) {
-		spin_unlock(&msg_queue_spinlock);
-		ret = -EINVAL;
-		goto out;
-	}
+	rcu_read_lock();
+	for (i = 0; i < state->unused_service; i++) {
+		struct vchiq_service *service;
+		struct vchiq_instance *instance;
 
-	header = user_service->msg_queue[user_service->msg_remove &
-		(MSG_QUEUE_SIZE - 1)];
-	user_service->msg_remove++;
-	spin_unlock(&msg_queue_spinlock);
+		service = rcu_dereference(state->services[i]);
+		if (!service || service->base.callback != service_callback)
+			continue;
 
-	complete(&user_service->remove_event);
-	if (!header) {
-		ret = -ENOTCONN;
-	} else if (header->size <= args->bufsize) {
-		/* Copy to user space if msgbuf is not NULL */
-		if (!args->buf || (copy_to_user(args->buf,
-					header->data, header->size) == 0)) {
-			ret = header->size;
-			vchiq_release_message(service->handle, header);
-		} else {
-			ret = -EFAULT;
-		}
-	} else {
-		vchiq_log_error(vchiq_arm_log_level,
-			"header %pK: bufsize %x < size %x",
-			header, args->bufsize, header->size);
-		WARN(1, "invalid size\n");
-		ret = -EMSGSIZE;
+		instance = service->instance;
+		if (instance)
+			instance->mark = 0;
 	}
-	DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
-out:
-	vchiq_service_put(service);
-	return ret;
-}
-
-static int vchiq_irq_queue_bulk_tx_rx(struct vchiq_instance *instance,
-				      struct vchiq_queue_bulk_transfer *args,
-				      enum vchiq_bulk_dir dir,
-				      enum vchiq_bulk_mode __user *mode)
-{
-	struct vchiq_service *service;
-	struct bulk_waiter_node *waiter = NULL;
-	bool found = false;
-	void *userdata;
-	int status = 0;
-	int ret;
-
-	service = find_service_for_instance(instance, args->handle);
-	if (!service)
-		return -EINVAL;
+	rcu_read_unlock();
 
-	if (args->mode == VCHIQ_BULK_MODE_BLOCKING) {
-		waiter = kzalloc(sizeof(*waiter), GFP_KERNEL);
-		if (!waiter) {
-			ret = -ENOMEM;
-			goto out;
-		}
+	for (i = 0; i < state->unused_service; i++) {
+		struct vchiq_service *service;
+		struct vchiq_instance *instance;
+		int err;
 
-		userdata = &waiter->bulk_waiter;
-	} else if (args->mode == VCHIQ_BULK_MODE_WAITING) {
-		mutex_lock(&instance->bulk_waiter_list_mutex);
-		list_for_each_entry(waiter, &instance->bulk_waiter_list,
-				    list) {
-			if (waiter->pid == current->pid) {
-				list_del(&waiter->list);
-				found = true;
-				break;
-			}
-		}
-		mutex_unlock(&instance->bulk_waiter_list_mutex);
-		if (!found) {
-			vchiq_log_error(vchiq_arm_log_level,
-				"no bulk_waiter found for pid %d",
-				current->pid);
-			ret = -ESRCH;
-			goto out;
+		rcu_read_lock();
+		service = rcu_dereference(state->services[i]);
+		if (!service || service->base.callback != service_callback) {
+			rcu_read_unlock();
+			continue;
 		}
-		vchiq_log_info(vchiq_arm_log_level,
-			"found bulk_waiter %pK for pid %d", waiter,
-			current->pid);
-		userdata = &waiter->bulk_waiter;
-	} else {
-		userdata = args->userdata;
-	}
 
-	status = vchiq_bulk_transfer(args->handle, NULL, args->data, args->size,
-				     userdata, args->mode, dir);
-
-	if (!waiter) {
-		ret = 0;
-		goto out;
-	}
-
-	if ((status != VCHIQ_RETRY) || fatal_signal_pending(current) ||
-		!waiter->bulk_waiter.bulk) {
-		if (waiter->bulk_waiter.bulk) {
-			/* Cancel the signal when the transfer completes. */
-			spin_lock(&bulk_waiter_spinlock);
-			waiter->bulk_waiter.bulk->userdata = NULL;
-			spin_unlock(&bulk_waiter_spinlock);
+		instance = service->instance;
+		if (!instance || instance->mark) {
+			rcu_read_unlock();
+			continue;
 		}
-		kfree(waiter);
-		ret = 0;
-	} else {
-		const enum vchiq_bulk_mode mode_waiting =
-			VCHIQ_BULK_MODE_WAITING;
-		waiter->pid = current->pid;
-		mutex_lock(&instance->bulk_waiter_list_mutex);
-		list_add(&waiter->list, &instance->bulk_waiter_list);
-		mutex_unlock(&instance->bulk_waiter_list_mutex);
-		vchiq_log_info(vchiq_arm_log_level,
-			"saved bulk_waiter %pK for pid %d",
-			waiter, current->pid);
+		rcu_read_unlock();
 
-		ret = put_user(mode_waiting, mode);
+		len = snprintf(buf, sizeof(buf),
+			       "Instance %pK: pid %d,%s completions %d/%d",
+			       instance, instance->pid,
+			       instance->connected ? " connected, " :
+			       "",
+			       instance->completion_insert -
+			       instance->completion_remove,
+			       MAX_COMPLETIONS);
+		err = vchiq_dump(dump_context, buf, len + 1);
+		if (err)
+			return err;
+		instance->mark = 1;
 	}
-out:
-	vchiq_service_put(service);
-	if (ret)
-		return ret;
-	else if (status == VCHIQ_ERROR)
-		return -EIO;
-	else if (status == VCHIQ_RETRY)
-		return -EINTR;
 	return 0;
 }
 
-/* read a user pointer value from an array pointers in user space */
-static inline int vchiq_get_user_ptr(void __user **buf, void __user *ubuf, int index)
+int vchiq_dump_platform_service_state(void *dump_context,
+				      struct vchiq_service *service)
 {
-	int ret;
-
-	if (in_compat_syscall()) {
-		compat_uptr_t ptr32;
-		compat_uptr_t __user *uptr = ubuf;
-
-		ret = get_user(ptr32, uptr + index);
-		if (ret)
-			return ret;
-
-		*buf = compat_ptr(ptr32);
-	} else {
-		uintptr_t ptr, __user *uptr = ubuf;
-
-		ret = get_user(ptr, uptr + index);
-
-		if (ret)
-			return ret;
-
-		*buf = (void __user *)ptr;
-	}
+	struct user_service *user_service =
+			(struct user_service *)service->base.userdata;
+	char buf[80];
+	int len;
 
-	return 0;
-}
+	len = scnprintf(buf, sizeof(buf), "  instance %pK", service->instance);
 
-struct vchiq_completion_data32 {
-	enum vchiq_reason reason;
-	compat_uptr_t header;
-	compat_uptr_t service_userdata;
-	compat_uptr_t bulk_userdata;
-};
+	if ((service->base.callback == service_callback) &&
+		user_service->is_vchi) {
+		len += scnprintf(buf + len, sizeof(buf) - len,
+			", %d/%d messages",
+			user_service->msg_insert - user_service->msg_remove,
+			MSG_QUEUE_SIZE);
 
-static int vchiq_put_completion(struct vchiq_completion_data __user *buf,
-				struct vchiq_completion_data *completion,
-				int index)
-{
-	struct vchiq_completion_data32 __user *buf32 = (void __user *)buf;
-
-	if (in_compat_syscall()) {
-		struct vchiq_completion_data32 tmp = {
-			.reason		  = completion->reason,
-			.header		  = ptr_to_compat(completion->header),
-			.service_userdata = ptr_to_compat(completion->service_userdata),
-			.bulk_userdata	  = ptr_to_compat(completion->bulk_userdata),
-		};
-		if (copy_to_user(&buf32[index], &tmp, sizeof(tmp)))
-			return -EFAULT;
-	} else {
-		if (copy_to_user(&buf[index], completion, sizeof(*completion)))
-			return -EFAULT;
+		if (user_service->dequeue_pending)
+			len += scnprintf(buf + len, sizeof(buf) - len,
+				" (dequeue pending)");
 	}
 
-	return 0;
+	return vchiq_dump(dump_context, buf, len + 1);
 }
 
-static int vchiq_ioc_await_completion(struct vchiq_instance *instance,
-				      struct vchiq_await_completion *args,
-				      int __user *msgbufcountp)
+struct vchiq_state *
+vchiq_get_state(void)
 {
-	int msgbufcount;
-	int remove;
-	int ret;
-
-	DEBUG_INITIALISE(g_state.local)
-
-	DEBUG_TRACE(AWAIT_COMPLETION_LINE);
-	if (!instance->connected) {
-		return -ENOTCONN;
-	}
-
-	mutex_lock(&instance->completion_mutex);
-
-	DEBUG_TRACE(AWAIT_COMPLETION_LINE);
-	while ((instance->completion_remove == instance->completion_insert)
-		&& !instance->closing) {
-		int rc;
-
-		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
-		mutex_unlock(&instance->completion_mutex);
-		rc = wait_for_completion_interruptible(
-					&instance->insert_event);
-		mutex_lock(&instance->completion_mutex);
-		if (rc) {
-			DEBUG_TRACE(AWAIT_COMPLETION_LINE);
-			vchiq_log_info(vchiq_arm_log_level,
-				"AWAIT_COMPLETION interrupted");
-			ret = -EINTR;
-			goto out;
-		}
-	}
-	DEBUG_TRACE(AWAIT_COMPLETION_LINE);
-
-	msgbufcount = args->msgbufcount;
-	remove = instance->completion_remove;
-
-	for (ret = 0; ret < args->count; ret++) {
-		struct vchiq_completion_data_kernel *completion;
-		struct vchiq_completion_data user_completion;
-		struct vchiq_service *service;
-		struct user_service *user_service;
-		struct vchiq_header *header;
-
-		if (remove == instance->completion_insert)
-			break;
 
-		completion = &instance->completions[
-			remove & (MAX_COMPLETIONS - 1)];
-
-		/*
-		 * A read memory barrier is needed to stop
-		 * prefetch of a stale completion record
-		 */
-		rmb();
-
-		service = completion->service_userdata;
-		user_service = service->base.userdata;
-
-		memset(&user_completion, 0, sizeof(user_completion));
-		user_completion = (struct vchiq_completion_data) {
-			.reason = completion->reason,
-			.service_userdata = user_service->userdata,
-		};
-
-		header = completion->header;
-		if (header) {
-			void __user *msgbuf;
-			int msglen;
-
-			msglen = header->size + sizeof(struct vchiq_header);
-			/* This must be a VCHIQ-style service */
-			if (args->msgbufsize < msglen) {
-				vchiq_log_error(vchiq_arm_log_level,
-					"header %pK: msgbufsize %x < msglen %x",
-					header, args->msgbufsize, msglen);
-				WARN(1, "invalid message size\n");
-				if (ret == 0)
-					ret = -EMSGSIZE;
-				break;
-			}
-			if (msgbufcount <= 0)
-				/* Stall here for lack of a buffer for the message. */
-				break;
-			/* Get the pointer from user space */
-			msgbufcount--;
-			if (vchiq_get_user_ptr(&msgbuf, args->msgbufs,
-						msgbufcount)) {
-				if (ret == 0)
-					ret = -EFAULT;
-				break;
-			}
-
-			/* Copy the message to user space */
-			if (copy_to_user(msgbuf, header, msglen)) {
-				if (ret == 0)
-					ret = -EFAULT;
-				break;
-			}
-
-			/* Now it has been copied, the message can be released. */
-			vchiq_release_message(service->handle, header);
-
-			/* The completion must point to the msgbuf. */
-			user_completion.header = msgbuf;
-		}
-
-		if ((completion->reason == VCHIQ_SERVICE_CLOSED) &&
-		    !instance->use_close_delivered)
-			vchiq_service_put(service);
-
-		/*
-		 * FIXME: address space mismatch, does bulk_userdata
-		 * actually point to user or kernel memory?
-		 */
-		user_completion.bulk_userdata = completion->bulk_userdata;
-
-		if (vchiq_put_completion(args->buf, &user_completion, ret)) {
-			if (ret == 0)
-				ret = -EFAULT;
-			break;
-		}
-
-		/*
-		 * Ensure that the above copy has completed
-		 * before advancing the remove pointer.
-		 */
-		mb();
-		remove++;
-		instance->completion_remove = remove;
-	}
-
-	if (msgbufcount != args->msgbufcount) {
-		if (put_user(msgbufcount, msgbufcountp))
-			ret = -EFAULT;
-	}
-out:
-	if (ret)
-		complete(&instance->remove_event);
-	mutex_unlock(&instance->completion_mutex);
-	DEBUG_TRACE(AWAIT_COMPLETION_LINE);
-
-	return ret;
-}
-
-static long
-vchiq_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
-{
-	struct vchiq_instance *instance = file->private_data;
-	enum vchiq_status status = VCHIQ_SUCCESS;
-	struct vchiq_service *service = NULL;
-	long ret = 0;
-	int i, rc;
-
-	vchiq_log_trace(vchiq_arm_log_level,
-		"%s - instance %pK, cmd %s, arg %lx",
-		__func__, instance,
-		((_IOC_TYPE(cmd) == VCHIQ_IOC_MAGIC) &&
-		(_IOC_NR(cmd) <= VCHIQ_IOC_MAX)) ?
-		ioctl_names[_IOC_NR(cmd)] : "<invalid>", arg);
-
-	switch (cmd) {
-	case VCHIQ_IOC_SHUTDOWN:
-		if (!instance->connected)
-			break;
-
-		/* Remove all services */
-		i = 0;
-		while ((service = next_service_by_instance(instance->state,
-			instance, &i))) {
-			status = vchiq_remove_service(service->handle);
-			vchiq_service_put(service);
-			if (status != VCHIQ_SUCCESS)
-				break;
-		}
-		service = NULL;
-
-		if (status == VCHIQ_SUCCESS) {
-			/* Wake the completion thread and ask it to exit */
-			instance->closing = 1;
-			complete(&instance->insert_event);
-		}
-
-		break;
-
-	case VCHIQ_IOC_CONNECT:
-		if (instance->connected) {
-			ret = -EINVAL;
-			break;
-		}
-		rc = mutex_lock_killable(&instance->state->mutex);
-		if (rc) {
-			vchiq_log_error(vchiq_arm_log_level,
-				"vchiq: connect: could not lock mutex for state %d: %d",
-				instance->state->id, rc);
-			ret = -EINTR;
-			break;
-		}
-		status = vchiq_connect_internal(instance->state, instance);
-		mutex_unlock(&instance->state->mutex);
-
-		if (status == VCHIQ_SUCCESS)
-			instance->connected = 1;
-		else
-			vchiq_log_error(vchiq_arm_log_level,
-				"vchiq: could not connect: %d", status);
-		break;
-
-	case VCHIQ_IOC_CREATE_SERVICE: {
-		struct vchiq_create_service __user *argp;
-		struct vchiq_create_service args;
-
-		argp = (void __user *)arg;
-		if (copy_from_user(&args, argp, sizeof(args))) {
-			ret = -EFAULT;
-			break;
-		}
-
-		ret = vchiq_ioc_create_service(instance, &args);
-		if (ret < 0)
-			break;
-
-		if (put_user(args.handle, &argp->handle)) {
-			vchiq_remove_service(args.handle);
-			ret = -EFAULT;
-		}
-	} break;
-
-	case VCHIQ_IOC_CLOSE_SERVICE:
-	case VCHIQ_IOC_REMOVE_SERVICE: {
-		unsigned int handle = (unsigned int)arg;
-		struct user_service *user_service;
-
-		service = find_service_for_instance(instance, handle);
-		if (!service) {
-			ret = -EINVAL;
-			break;
-		}
-
-		user_service = service->base.userdata;
-
-		/*
-		 * close_pending is false on first entry, and when the
-		 * wait in vchiq_close_service has been interrupted.
-		 */
-		if (!user_service->close_pending) {
-			status = (cmd == VCHIQ_IOC_CLOSE_SERVICE) ?
-				 vchiq_close_service(service->handle) :
-				 vchiq_remove_service(service->handle);
-			if (status != VCHIQ_SUCCESS)
-				break;
-		}
-
-		/*
-		 * close_pending is true once the underlying service
-		 * has been closed until the client library calls the
-		 * CLOSE_DELIVERED ioctl, signalling close_event.
-		 */
-		if (user_service->close_pending &&
-			wait_for_completion_interruptible(
-				&user_service->close_event))
-			status = VCHIQ_RETRY;
-		break;
-	}
-
-	case VCHIQ_IOC_USE_SERVICE:
-	case VCHIQ_IOC_RELEASE_SERVICE:	{
-		unsigned int handle = (unsigned int)arg;
-
-		service = find_service_for_instance(instance, handle);
-		if (service) {
-			ret = (cmd == VCHIQ_IOC_USE_SERVICE) ?
-				vchiq_use_service_internal(service) :
-				vchiq_release_service_internal(service);
-			if (ret) {
-				vchiq_log_error(vchiq_susp_log_level,
-					"%s: cmd %s returned error %ld for service %c%c%c%c:%03d",
-					__func__,
-					(cmd == VCHIQ_IOC_USE_SERVICE) ?
-						"VCHIQ_IOC_USE_SERVICE" :
-						"VCHIQ_IOC_RELEASE_SERVICE",
-					ret,
-					VCHIQ_FOURCC_AS_4CHARS(
-						service->base.fourcc),
-					service->client_id);
-			}
-		} else {
-			ret = -EINVAL;
-		}
-	} break;
-
-	case VCHIQ_IOC_QUEUE_MESSAGE: {
-		struct vchiq_queue_message args;
-
-		if (copy_from_user(&args, (const void __user *)arg,
-				   sizeof(args))) {
-			ret = -EFAULT;
-			break;
-		}
-
-		service = find_service_for_instance(instance, args.handle);
-
-		if (service && (args.count <= MAX_ELEMENTS)) {
-			/* Copy elements into kernel space */
-			struct vchiq_element elements[MAX_ELEMENTS];
-
-			if (copy_from_user(elements, args.elements,
-				args.count * sizeof(struct vchiq_element)) == 0)
-				ret = vchiq_ioc_queue_message(args.handle, elements,
-							      args.count);
-			else
-				ret = -EFAULT;
-		} else {
-			ret = -EINVAL;
-		}
-	} break;
-
-	case VCHIQ_IOC_QUEUE_BULK_TRANSMIT:
-	case VCHIQ_IOC_QUEUE_BULK_RECEIVE: {
-		struct vchiq_queue_bulk_transfer args;
-		struct vchiq_queue_bulk_transfer __user *argp;
-
-		enum vchiq_bulk_dir dir =
-			(cmd == VCHIQ_IOC_QUEUE_BULK_TRANSMIT) ?
-			VCHIQ_BULK_TRANSMIT : VCHIQ_BULK_RECEIVE;
-
-		argp = (void __user *)arg;
-		if (copy_from_user(&args, argp, sizeof(args))) {
-			ret = -EFAULT;
-			break;
-		}
-
-		ret = vchiq_irq_queue_bulk_tx_rx(instance, &args,
-						 dir, &argp->mode);
-	} break;
-
-	case VCHIQ_IOC_AWAIT_COMPLETION: {
-		struct vchiq_await_completion args;
-		struct vchiq_await_completion __user *argp;
-
-		argp = (void __user *)arg;
-		if (copy_from_user(&args, argp, sizeof(args))) {
-			ret = -EFAULT;
-			break;
-		}
-
-		ret = vchiq_ioc_await_completion(instance, &args,
-						 &argp->msgbufcount);
-	} break;
-
-	case VCHIQ_IOC_DEQUEUE_MESSAGE: {
-		struct vchiq_dequeue_message args;
-
-		if (copy_from_user(&args, (const void __user *)arg,
-				   sizeof(args))) {
-			ret = -EFAULT;
-			break;
-		}
-
-		ret = vchiq_ioc_dequeue_message(instance, &args);
-	} break;
-
-	case VCHIQ_IOC_GET_CLIENT_ID: {
-		unsigned int handle = (unsigned int)arg;
-
-		ret = vchiq_get_client_id(handle);
-	} break;
-
-	case VCHIQ_IOC_GET_CONFIG: {
-		struct vchiq_get_config args;
-		struct vchiq_config config;
-
-		if (copy_from_user(&args, (const void __user *)arg,
-				   sizeof(args))) {
-			ret = -EFAULT;
-			break;
-		}
-		if (args.config_size > sizeof(config)) {
-			ret = -EINVAL;
-			break;
-		}
-
-		vchiq_get_config(&config);
-		if (copy_to_user(args.pconfig, &config, args.config_size)) {
-			ret = -EFAULT;
-			break;
-		}
-	} break;
-
-	case VCHIQ_IOC_SET_SERVICE_OPTION: {
-		struct vchiq_set_service_option args;
-
-		if (copy_from_user(&args, (const void __user *)arg,
-				   sizeof(args))) {
-			ret = -EFAULT;
-			break;
-		}
-
-		service = find_service_for_instance(instance, args.handle);
-		if (!service) {
-			ret = -EINVAL;
-			break;
-		}
-
-		ret = vchiq_set_service_option(args.handle, args.option,
-					       args.value);
-	} break;
-
-	case VCHIQ_IOC_LIB_VERSION: {
-		unsigned int lib_version = (unsigned int)arg;
-
-		if (lib_version < VCHIQ_VERSION_MIN)
-			ret = -EINVAL;
-		else if (lib_version >= VCHIQ_VERSION_CLOSE_DELIVERED)
-			instance->use_close_delivered = 1;
-	} break;
-
-	case VCHIQ_IOC_CLOSE_DELIVERED: {
-		unsigned int handle = (unsigned int)arg;
-
-		service = find_closed_service_for_instance(instance, handle);
-		if (service) {
-			struct user_service *user_service =
-				(struct user_service *)service->base.userdata;
-			close_delivered(user_service);
-		} else {
-			ret = -EINVAL;
-		}
-	} break;
-
-	default:
-		ret = -ENOTTY;
-		break;
-	}
-
-	if (service)
-		vchiq_service_put(service);
-
-	if (ret == 0) {
-		if (status == VCHIQ_ERROR)
-			ret = -EIO;
-		else if (status == VCHIQ_RETRY)
-			ret = -EINTR;
-	}
-
-	if ((status == VCHIQ_SUCCESS) && (ret < 0) && (ret != -EINTR) &&
-		(ret != -EWOULDBLOCK))
-		vchiq_log_info(vchiq_arm_log_level,
-			"  ioctl instance %pK, cmd %s -> status %d, %ld",
-			instance,
-			(_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
-				ioctl_names[_IOC_NR(cmd)] :
-				"<invalid>",
-			status, ret);
-	else
-		vchiq_log_trace(vchiq_arm_log_level,
-			"  ioctl instance %pK, cmd %s -> status %d, %ld",
-			instance,
-			(_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
-				ioctl_names[_IOC_NR(cmd)] :
-				"<invalid>",
-			status, ret);
-
-	return ret;
-}
-
-#if defined(CONFIG_COMPAT)
-
-struct vchiq_service_params32 {
-	int fourcc;
-	compat_uptr_t callback;
-	compat_uptr_t userdata;
-	short version; /* Increment for non-trivial changes */
-	short version_min; /* Update for incompatible changes */
-};
-
-struct vchiq_create_service32 {
-	struct vchiq_service_params32 params;
-	int is_open;
-	int is_vchi;
-	unsigned int handle; /* OUT */
-};
-
-#define VCHIQ_IOC_CREATE_SERVICE32 \
-	_IOWR(VCHIQ_IOC_MAGIC, 2, struct vchiq_create_service32)
-
-static long
-vchiq_compat_ioctl_create_service(struct file *file, unsigned int cmd,
-				  struct vchiq_create_service32 __user *ptrargs32)
-{
-	struct vchiq_create_service args;
-	struct vchiq_create_service32 args32;
-	long ret;
-
-	if (copy_from_user(&args32, ptrargs32, sizeof(args32)))
-		return -EFAULT;
-
-	args = (struct vchiq_create_service) {
-		.params = {
-			.fourcc	     = args32.params.fourcc,
-			.callback    = compat_ptr(args32.params.callback),
-			.userdata    = compat_ptr(args32.params.userdata),
-			.version     = args32.params.version,
-			.version_min = args32.params.version_min,
-		},
-		.is_open = args32.is_open,
-		.is_vchi = args32.is_vchi,
-		.handle  = args32.handle,
-	};
-
-	ret = vchiq_ioc_create_service(file->private_data, &args);
-	if (ret < 0)
-		return ret;
-
-	if (put_user(args.handle, &ptrargs32->handle)) {
-		vchiq_remove_service(args.handle);
-		return -EFAULT;
-	}
-
-	return 0;
-}
-
-struct vchiq_element32 {
-	compat_uptr_t data;
-	unsigned int size;
-};
-
-struct vchiq_queue_message32 {
-	unsigned int handle;
-	unsigned int count;
-	compat_uptr_t elements;
-};
-
-#define VCHIQ_IOC_QUEUE_MESSAGE32 \
-	_IOW(VCHIQ_IOC_MAGIC,  4, struct vchiq_queue_message32)
-
-static long
-vchiq_compat_ioctl_queue_message(struct file *file,
-				 unsigned int cmd,
-				 struct vchiq_queue_message32 __user *arg)
-{
-	struct vchiq_queue_message args;
-	struct vchiq_queue_message32 args32;
-	struct vchiq_service *service;
-	int ret;
-
-	if (copy_from_user(&args32, arg, sizeof(args32)))
-		return -EFAULT;
-
-	args = (struct vchiq_queue_message) {
-		.handle   = args32.handle,
-		.count    = args32.count,
-		.elements = compat_ptr(args32.elements),
-	};
-
-	if (args32.count > MAX_ELEMENTS)
-		return -EINVAL;
-
-	service = find_service_for_instance(file->private_data, args.handle);
-	if (!service)
-		return -EINVAL;
-
-	if (args32.elements && args32.count) {
-		struct vchiq_element32 element32[MAX_ELEMENTS];
-		struct vchiq_element elements[MAX_ELEMENTS];
-		unsigned int count;
-
-		if (copy_from_user(&element32, args.elements,
-				   sizeof(element32))) {
-			vchiq_service_put(service);
-			return -EFAULT;
-		}
-
-		for (count = 0; count < args32.count; count++) {
-			elements[count].data =
-				compat_ptr(element32[count].data);
-			elements[count].size = element32[count].size;
-		}
-		ret = vchiq_ioc_queue_message(args.handle, elements,
-					      args.count);
-	} else {
-		ret = -EINVAL;
-	}
-	vchiq_service_put(service);
-
-	return ret;
-}
-
-struct vchiq_queue_bulk_transfer32 {
-	unsigned int handle;
-	compat_uptr_t data;
-	unsigned int size;
-	compat_uptr_t userdata;
-	enum vchiq_bulk_mode mode;
-};
-
-#define VCHIQ_IOC_QUEUE_BULK_TRANSMIT32 \
-	_IOWR(VCHIQ_IOC_MAGIC, 5, struct vchiq_queue_bulk_transfer32)
-#define VCHIQ_IOC_QUEUE_BULK_RECEIVE32 \
-	_IOWR(VCHIQ_IOC_MAGIC, 6, struct vchiq_queue_bulk_transfer32)
-
-static long
-vchiq_compat_ioctl_queue_bulk(struct file *file,
-			      unsigned int cmd,
-			      struct vchiq_queue_bulk_transfer32 __user *argp)
-{
-	struct vchiq_queue_bulk_transfer32 args32;
-	struct vchiq_queue_bulk_transfer args;
-	enum vchiq_bulk_dir dir = (cmd == VCHIQ_IOC_QUEUE_BULK_TRANSMIT32) ?
-				  VCHIQ_BULK_TRANSMIT : VCHIQ_BULK_RECEIVE;
-
-	if (copy_from_user(&args32, argp, sizeof(args32)))
-		return -EFAULT;
-
-	args = (struct vchiq_queue_bulk_transfer) {
-		.handle   = args32.handle,
-		.data	  = compat_ptr(args32.data),
-		.size	  = args32.size,
-		.userdata = compat_ptr(args32.userdata),
-		.mode	  = args32.mode,
-	};
-
-	return vchiq_irq_queue_bulk_tx_rx(file->private_data, &args,
-					  dir, &argp->mode);
-}
-
-struct vchiq_await_completion32 {
-	unsigned int count;
-	compat_uptr_t buf;
-	unsigned int msgbufsize;
-	unsigned int msgbufcount; /* IN/OUT */
-	compat_uptr_t msgbufs;
-};
-
-#define VCHIQ_IOC_AWAIT_COMPLETION32 \
-	_IOWR(VCHIQ_IOC_MAGIC, 7, struct vchiq_await_completion32)
-
-static long
-vchiq_compat_ioctl_await_completion(struct file *file,
-				    unsigned int cmd,
-				    struct vchiq_await_completion32 __user *argp)
-{
-	struct vchiq_await_completion args;
-	struct vchiq_await_completion32 args32;
-
-	if (copy_from_user(&args32, argp, sizeof(args32)))
-		return -EFAULT;
-
-	args = (struct vchiq_await_completion) {
-		.count		= args32.count,
-		.buf		= compat_ptr(args32.buf),
-		.msgbufsize	= args32.msgbufsize,
-		.msgbufcount	= args32.msgbufcount,
-		.msgbufs	= compat_ptr(args32.msgbufs),
-	};
-
-	return vchiq_ioc_await_completion(file->private_data, &args,
-					  &argp->msgbufcount);
-}
-
-struct vchiq_dequeue_message32 {
-	unsigned int handle;
-	int blocking;
-	unsigned int bufsize;
-	compat_uptr_t buf;
-};
-
-#define VCHIQ_IOC_DEQUEUE_MESSAGE32 \
-	_IOWR(VCHIQ_IOC_MAGIC, 8, struct vchiq_dequeue_message32)
-
-static long
-vchiq_compat_ioctl_dequeue_message(struct file *file,
-				   unsigned int cmd,
-				   struct vchiq_dequeue_message32 __user *arg)
-{
-	struct vchiq_dequeue_message32 args32;
-	struct vchiq_dequeue_message args;
-
-	if (copy_from_user(&args32, arg, sizeof(args32)))
-		return -EFAULT;
-
-	args = (struct vchiq_dequeue_message) {
-		.handle		= args32.handle,
-		.blocking	= args32.blocking,
-		.bufsize	= args32.bufsize,
-		.buf		= compat_ptr(args32.buf),
-	};
-
-	return vchiq_ioc_dequeue_message(file->private_data, &args);
-}
-
-struct vchiq_get_config32 {
-	unsigned int config_size;
-	compat_uptr_t pconfig;
-};
-
-#define VCHIQ_IOC_GET_CONFIG32 \
-	_IOWR(VCHIQ_IOC_MAGIC, 10, struct vchiq_get_config32)
-
-static long
-vchiq_compat_ioctl_get_config(struct file *file,
-			      unsigned int cmd,
-			      struct vchiq_get_config32 __user *arg)
-{
-	struct vchiq_get_config32 args32;
-	struct vchiq_config config;
-	void __user *ptr;
-
-	if (copy_from_user(&args32, arg, sizeof(args32)))
-		return -EFAULT;
-	if (args32.config_size > sizeof(config))
-		return -EINVAL;
-
-	vchiq_get_config(&config);
-	ptr = compat_ptr(args32.pconfig);
-	if (copy_to_user(ptr, &config, args32.config_size))
-		return -EFAULT;
-
-	return 0;
-}
-
-static long
-vchiq_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
-{
-	void __user *argp = compat_ptr(arg);
-
-	switch (cmd) {
-	case VCHIQ_IOC_CREATE_SERVICE32:
-		return vchiq_compat_ioctl_create_service(file, cmd, argp);
-	case VCHIQ_IOC_QUEUE_MESSAGE32:
-		return vchiq_compat_ioctl_queue_message(file, cmd, argp);
-	case VCHIQ_IOC_QUEUE_BULK_TRANSMIT32:
-	case VCHIQ_IOC_QUEUE_BULK_RECEIVE32:
-		return vchiq_compat_ioctl_queue_bulk(file, cmd, argp);
-	case VCHIQ_IOC_AWAIT_COMPLETION32:
-		return vchiq_compat_ioctl_await_completion(file, cmd, argp);
-	case VCHIQ_IOC_DEQUEUE_MESSAGE32:
-		return vchiq_compat_ioctl_dequeue_message(file, cmd, argp);
-	case VCHIQ_IOC_GET_CONFIG32:
-		return vchiq_compat_ioctl_get_config(file, cmd, argp);
-	default:
-		return vchiq_ioctl(file, cmd, (unsigned long)argp);
-	}
-}
-
-#endif
-
-static int vchiq_open(struct inode *inode, struct file *file)
-{
-	struct vchiq_state *state = vchiq_get_state();
-	struct vchiq_instance *instance;
-
-	vchiq_log_info(vchiq_arm_log_level, "vchiq_open");
-
-	if (!state) {
-		vchiq_log_error(vchiq_arm_log_level,
-				"vchiq has no connection to VideoCore");
-		return -ENOTCONN;
-	}
-
-	instance = kzalloc(sizeof(*instance), GFP_KERNEL);
-	if (!instance)
-		return -ENOMEM;
-
-	instance->state = state;
-	instance->pid = current->tgid;
-
-	vchiq_debugfs_add_instance(instance);
-
-	init_completion(&instance->insert_event);
-	init_completion(&instance->remove_event);
-	mutex_init(&instance->completion_mutex);
-	mutex_init(&instance->bulk_waiter_list_mutex);
-	INIT_LIST_HEAD(&instance->bulk_waiter_list);
-
-	file->private_data = instance;
-
-	return 0;
-}
-
-static int vchiq_release(struct inode *inode, struct file *file)
-{
-	struct vchiq_instance *instance = file->private_data;
-	struct vchiq_state *state = vchiq_get_state();
-	struct vchiq_service *service;
-	int ret = 0;
-	int i;
-
-	vchiq_log_info(vchiq_arm_log_level, "%s: instance=%lx", __func__,
-		       (unsigned long)instance);
-
-	if (!state) {
-		ret = -EPERM;
-		goto out;
-	}
-
-	/* Ensure videocore is awake to allow termination. */
-	vchiq_use_internal(instance->state, NULL, USE_TYPE_VCHIQ);
-
-	mutex_lock(&instance->completion_mutex);
-
-	/* Wake the completion thread and ask it to exit */
-	instance->closing = 1;
-	complete(&instance->insert_event);
-
-	mutex_unlock(&instance->completion_mutex);
-
-	/* Wake the slot handler if the completion queue is full. */
-	complete(&instance->remove_event);
-
-	/* Mark all services for termination... */
-	i = 0;
-	while ((service = next_service_by_instance(state, instance, &i))) {
-		struct user_service *user_service = service->base.userdata;
-
-		/* Wake the slot handler if the msg queue is full. */
-		complete(&user_service->remove_event);
-
-		vchiq_terminate_service_internal(service);
-		vchiq_service_put(service);
-	}
-
-	/* ...and wait for them to die */
-	i = 0;
-	while ((service = next_service_by_instance(state, instance, &i))) {
-		struct user_service *user_service = service->base.userdata;
-
-		wait_for_completion(&service->remove_event);
-
-		if (WARN_ON(service->srvstate != VCHIQ_SRVSTATE_FREE)) {
-			vchiq_service_put(service);
-			break;
-		}
-
-		spin_lock(&msg_queue_spinlock);
-
-		while (user_service->msg_remove != user_service->msg_insert) {
-			struct vchiq_header *header;
-			int m = user_service->msg_remove & (MSG_QUEUE_SIZE - 1);
-
-			header = user_service->msg_queue[m];
-			user_service->msg_remove++;
-			spin_unlock(&msg_queue_spinlock);
-
-			if (header)
-				vchiq_release_message(service->handle, header);
-			spin_lock(&msg_queue_spinlock);
-		}
-
-		spin_unlock(&msg_queue_spinlock);
-
-		vchiq_service_put(service);
-	}
-
-	/* Release any closed services */
-	while (instance->completion_remove != instance->completion_insert) {
-		struct vchiq_completion_data_kernel *completion;
-		struct vchiq_service *service;
-
-		completion = &instance->completions[
-			instance->completion_remove & (MAX_COMPLETIONS - 1)];
-		service = completion->service_userdata;
-		if (completion->reason == VCHIQ_SERVICE_CLOSED) {
-			struct user_service *user_service =
-							service->base.userdata;
-
-			/* Wake any blocked user-thread */
-			if (instance->use_close_delivered)
-				complete(&user_service->close_event);
-			vchiq_service_put(service);
-		}
-		instance->completion_remove++;
-	}
-
-	/* Release the PEER service count. */
-	vchiq_release_internal(instance->state, NULL);
-
-	free_bulk_waiter(instance);
-
-	vchiq_debugfs_remove_instance(instance);
-
-	kfree(instance);
-	file->private_data = NULL;
-
-out:
-	return ret;
-}
-
-int vchiq_dump(void *dump_context, const char *str, int len)
-{
-	struct dump_context *context = (struct dump_context *)dump_context;
-	int copy_bytes;
-
-	if (context->actual >= context->space)
-		return 0;
-
-	if (context->offset > 0) {
-		int skip_bytes = min_t(int, len, context->offset);
-
-		str += skip_bytes;
-		len -= skip_bytes;
-		context->offset -= skip_bytes;
-		if (context->offset > 0)
-			return 0;
-	}
-	copy_bytes = min_t(int, len, context->space - context->actual);
-	if (copy_bytes == 0)
-		return 0;
-	if (copy_to_user(context->buf + context->actual, str,
-			 copy_bytes))
-		return -EFAULT;
-	context->actual += copy_bytes;
-	len -= copy_bytes;
-
-	/*
-	 * If the terminating NUL is included in the length, then it
-	 * marks the end of a line and should be replaced with a
-	 * carriage return.
-	 */
-	if ((len == 0) && (str[copy_bytes - 1] == '\0')) {
-		char cr = '\n';
-
-		if (copy_to_user(context->buf + context->actual - 1,
-				 &cr, 1))
-			return -EFAULT;
-	}
-	return 0;
-}
-
-int vchiq_dump_platform_instances(void *dump_context)
-{
-	struct vchiq_state *state = vchiq_get_state();
-	char buf[80];
-	int len;
-	int i;
-
-	/*
-	 * There is no list of instances, so instead scan all services,
-	 * marking those that have been dumped.
-	 */
-
-	rcu_read_lock();
-	for (i = 0; i < state->unused_service; i++) {
-		struct vchiq_service *service;
-		struct vchiq_instance *instance;
-
-		service = rcu_dereference(state->services[i]);
-		if (!service || service->base.callback != service_callback)
-			continue;
-
-		instance = service->instance;
-		if (instance)
-			instance->mark = 0;
-	}
-	rcu_read_unlock();
-
-	for (i = 0; i < state->unused_service; i++) {
-		struct vchiq_service *service;
-		struct vchiq_instance *instance;
-		int err;
-
-		rcu_read_lock();
-		service = rcu_dereference(state->services[i]);
-		if (!service || service->base.callback != service_callback) {
-			rcu_read_unlock();
-			continue;
-		}
-
-		instance = service->instance;
-		if (!instance || instance->mark) {
-			rcu_read_unlock();
-			continue;
-		}
-		rcu_read_unlock();
-
-		len = snprintf(buf, sizeof(buf),
-			       "Instance %pK: pid %d,%s completions %d/%d",
-			       instance, instance->pid,
-			       instance->connected ? " connected, " :
-			       "",
-			       instance->completion_insert -
-			       instance->completion_remove,
-			       MAX_COMPLETIONS);
-		err = vchiq_dump(dump_context, buf, len + 1);
-		if (err)
-			return err;
-		instance->mark = 1;
-	}
-	return 0;
-}
-
-int vchiq_dump_platform_service_state(void *dump_context,
-				      struct vchiq_service *service)
-{
-	struct user_service *user_service =
-			(struct user_service *)service->base.userdata;
-	char buf[80];
-	int len;
-
-	len = scnprintf(buf, sizeof(buf), "  instance %pK", service->instance);
-
-	if ((service->base.callback == service_callback) &&
-		user_service->is_vchi) {
-		len += scnprintf(buf + len, sizeof(buf) - len,
-			", %d/%d messages",
-			user_service->msg_insert - user_service->msg_remove,
-			MSG_QUEUE_SIZE);
-
-		if (user_service->dequeue_pending)
-			len += scnprintf(buf + len, sizeof(buf) - len,
-				" (dequeue pending)");
-	}
-
-	return vchiq_dump(dump_context, buf, len + 1);
-}
-
-static ssize_t
-vchiq_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
-{
-	struct dump_context context;
-	int err;
-
-	context.buf = buf;
-	context.actual = 0;
-	context.space = count;
-	context.offset = *ppos;
-
-	err = vchiq_dump_state(&context, &g_state);
-	if (err)
-		return err;
-
-	*ppos += context.actual;
-
-	return context.actual;
-}
-
-struct vchiq_state *
-vchiq_get_state(void)
-{
-
-	if (!g_state.remote)
-		pr_err("%s: g_state.remote == NULL\n", __func__);
-	else if (g_state.remote->initialised != 1)
-		pr_notice("%s: g_state.remote->initialised != 1 (%d)\n",
-			  __func__, g_state.remote->initialised);
+	if (!g_state.remote)
+		pr_err("%s: g_state.remote == NULL\n", __func__);
+	else if (g_state.remote->initialised != 1)
+		pr_notice("%s: g_state.remote->initialised != 1 (%d)\n",
+			  __func__, g_state.remote->initialised);
 
 	return (g_state.remote &&
 		(g_state.remote->initialised == 1)) ? &g_state : NULL;
 }
 
-static const struct file_operations
-vchiq_fops = {
-	.owner = THIS_MODULE,
-	.unlocked_ioctl = vchiq_ioctl,
-#if defined(CONFIG_COMPAT)
-	.compat_ioctl = vchiq_compat_ioctl,
-#endif
-	.open = vchiq_open,
-	.release = vchiq_release,
-	.read = vchiq_read
-};
-
-/**
- *	vchiq_register_chrdev - Register the char driver for vchiq
- *				and create the necessary class and
- *				device files in userspace.
- *	@parent		The parent of the char device.
- *
- *	Returns 0 on success else returns the error code.
- */
-int vchiq_register_chrdev(struct device *parent)
-{
-	struct device *vchiq_dev;
-	int ret;
-
-	vchiq_class = class_create(THIS_MODULE, DEVICE_NAME);
-	if (IS_ERR(vchiq_class)) {
-		pr_err("Failed to create vchiq class\n");
-		ret = PTR_ERR(vchiq_class);
-		goto error_exit;
-	}
-
-	ret = alloc_chrdev_region(&vchiq_devid, 0, 1, DEVICE_NAME);
-	if (ret) {
-		pr_err("vchiq: Failed to allocate vchiq's chrdev region\n");
-		goto alloc_region_error;
-	}
-
-	cdev_init(&vchiq_cdev, &vchiq_fops);
-	vchiq_cdev.owner = THIS_MODULE;
-	ret = cdev_add(&vchiq_cdev, vchiq_devid, 1);
-	if (ret) {
-		vchiq_log_error(vchiq_arm_log_level,
-				"Unable to register vchiq char device");
-		goto cdev_add_error;
-	}
-
-	vchiq_dev = device_create(vchiq_class, parent, vchiq_devid, NULL,
-				  DEVICE_NAME);
-	if (IS_ERR(vchiq_dev)) {
-		vchiq_log_error(vchiq_arm_log_level,
-				"Failed to create vchiq char device node");
-		ret = PTR_ERR(vchiq_dev);
-		goto device_create_error;
-	}
-
-	vchiq_log_info(vchiq_arm_log_level,
-		       "vchiq char dev initialised successfully - device %d.%d",
-			MAJOR(vchiq_devid), MINOR(vchiq_devid));
-
-	return 0;
-
-device_create_error:
-	cdev_del(&vchiq_cdev);
-
-cdev_add_error:
-	unregister_chrdev_region(vchiq_devid, 1);
-
-alloc_region_error:
-	class_destroy(vchiq_class);
-
-error_exit:
-	return ret;
-}
-
-/**
- *	vchiq_deregister_chrdev	- Deregister and cleanup the vchiq char
- *				  driver and device files
- */
-void vchiq_deregister_chrdev(void)
-{
-	device_destroy(vchiq_class, vchiq_devid);
-	cdev_del(&vchiq_cdev);
-	unregister_chrdev_region(vchiq_devid, 1);
-	class_destroy(vchiq_class);
-}
-
 /*
  * Autosuspend related functionality
  */
diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c
new file mode 100644
index 000000000000..bf1a88c9d1ee
--- /dev/null
+++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c
@@ -0,0 +1,1440 @@
+// SPDX-License-Identifier: GPL-2.0 OR BSD-3-Clause
+/*
+ * Copyright (c) 2014 Raspberry Pi (Trading) Ltd. All rights reserved.
+ * Copyright (c) 2010-2012 Broadcom. All rights reserved.
+ */
+
+#include <linux/cdev.h>
+#include <linux/fs.h>
+#include <linux/device.h>
+#include <linux/slab.h>
+#include <linux/compat.h>
+
+#include "vchiq_core.h"
+#include "vchiq_ioctl.h"
+#include "vchiq_arm.h"
+#include "vchiq_debugfs.h"
+
+#define DEVICE_NAME "vchiq"
+
+static struct cdev    vchiq_cdev;
+static dev_t          vchiq_devid;
+static struct class  *vchiq_class;
+
+static const char *const ioctl_names[] = {
+	"CONNECT",
+	"SHUTDOWN",
+	"CREATE_SERVICE",
+	"REMOVE_SERVICE",
+	"QUEUE_MESSAGE",
+	"QUEUE_BULK_TRANSMIT",
+	"QUEUE_BULK_RECEIVE",
+	"AWAIT_COMPLETION",
+	"DEQUEUE_MESSAGE",
+	"GET_CLIENT_ID",
+	"GET_CONFIG",
+	"CLOSE_SERVICE",
+	"USE_SERVICE",
+	"RELEASE_SERVICE",
+	"SET_SERVICE_OPTION",
+	"DUMP_PHYS_MEM",
+	"LIB_VERSION",
+	"CLOSE_DELIVERED"
+};
+
+static_assert(ARRAY_SIZE(ioctl_names) == (VCHIQ_IOC_MAX + 1));
+
+static void
+user_service_free(void *userdata)
+{
+	kfree(userdata);
+}
+
+static void close_delivered(struct user_service *user_service)
+{
+	vchiq_log_info(vchiq_arm_log_level,
+		"%s(handle=%x)",
+		__func__, user_service->service->handle);
+
+	if (user_service->close_pending) {
+		/* Allow the underlying service to be culled */
+		vchiq_service_put(user_service->service);
+
+		/* Wake the user-thread blocked in close_ or remove_service */
+		complete(&user_service->close_event);
+
+		user_service->close_pending = 0;
+	}
+}
+
+struct vchiq_io_copy_callback_context {
+	struct vchiq_element *element;
+	size_t element_offset;
+	unsigned long elements_to_go;
+};
+
+static ssize_t vchiq_ioc_copy_element_data(void *context, void *dest,
+					   size_t offset, size_t maxsize)
+{
+	struct vchiq_io_copy_callback_context *cc = context;
+	size_t total_bytes_copied = 0;
+	size_t bytes_this_round;
+
+	while (total_bytes_copied < maxsize) {
+		if (!cc->elements_to_go)
+			return total_bytes_copied;
+
+		if (!cc->element->size) {
+			cc->elements_to_go--;
+			cc->element++;
+			cc->element_offset = 0;
+			continue;
+		}
+
+		bytes_this_round = min(cc->element->size - cc->element_offset,
+				       maxsize - total_bytes_copied);
+
+		if (copy_from_user(dest + total_bytes_copied,
+				  cc->element->data + cc->element_offset,
+				  bytes_this_round))
+			return -EFAULT;
+
+		cc->element_offset += bytes_this_round;
+		total_bytes_copied += bytes_this_round;
+
+		if (cc->element_offset == cc->element->size) {
+			cc->elements_to_go--;
+			cc->element++;
+			cc->element_offset = 0;
+		}
+	}
+
+	return maxsize;
+}
+
+static int
+vchiq_ioc_queue_message(unsigned int handle, struct vchiq_element *elements,
+			unsigned long count)
+{
+	struct vchiq_io_copy_callback_context context;
+	enum vchiq_status status = VCHIQ_SUCCESS;
+	unsigned long i;
+	size_t total_size = 0;
+
+	context.element = elements;
+	context.element_offset = 0;
+	context.elements_to_go = count;
+
+	for (i = 0; i < count; i++) {
+		if (!elements[i].data && elements[i].size != 0)
+			return -EFAULT;
+
+		total_size += elements[i].size;
+	}
+
+	status = vchiq_queue_message(handle, vchiq_ioc_copy_element_data,
+				     &context, total_size);
+
+	if (status == VCHIQ_ERROR)
+		return -EIO;
+	else if (status == VCHIQ_RETRY)
+		return -EINTR;
+	return 0;
+}
+
+static int vchiq_ioc_create_service(struct vchiq_instance *instance,
+				    struct vchiq_create_service *args)
+{
+	struct user_service *user_service = NULL;
+	struct vchiq_service *service;
+	enum vchiq_status status = VCHIQ_SUCCESS;
+	struct vchiq_service_params_kernel params;
+	int srvstate;
+
+	user_service = kmalloc(sizeof(*user_service), GFP_KERNEL);
+	if (!user_service)
+		return -ENOMEM;
+
+	if (args->is_open) {
+		if (!instance->connected) {
+			kfree(user_service);
+			return -ENOTCONN;
+		}
+		srvstate = VCHIQ_SRVSTATE_OPENING;
+	} else {
+		srvstate = instance->connected ?
+			 VCHIQ_SRVSTATE_LISTENING : VCHIQ_SRVSTATE_HIDDEN;
+	}
+
+	params = (struct vchiq_service_params_kernel) {
+		.fourcc   = args->params.fourcc,
+		.callback = service_callback,
+		.userdata = user_service,
+		.version  = args->params.version,
+		.version_min = args->params.version_min,
+	};
+	service = vchiq_add_service_internal(instance->state, &params,
+					     srvstate, instance,
+					     user_service_free);
+	if (!service) {
+		kfree(user_service);
+		return -EEXIST;
+	}
+
+	user_service->service = service;
+	user_service->userdata = args->params.userdata;
+	user_service->instance = instance;
+	user_service->is_vchi = (args->is_vchi != 0);
+	user_service->dequeue_pending = 0;
+	user_service->close_pending = 0;
+	user_service->message_available_pos = instance->completion_remove - 1;
+	user_service->msg_insert = 0;
+	user_service->msg_remove = 0;
+	init_completion(&user_service->insert_event);
+	init_completion(&user_service->remove_event);
+	init_completion(&user_service->close_event);
+
+	if (args->is_open) {
+		status = vchiq_open_service_internal(service, instance->pid);
+		if (status != VCHIQ_SUCCESS) {
+			vchiq_remove_service(service->handle);
+			return (status == VCHIQ_RETRY) ?
+				-EINTR : -EIO;
+		}
+	}
+	args->handle = service->handle;
+
+	return 0;
+}
+
+static int vchiq_ioc_dequeue_message(struct vchiq_instance *instance,
+				     struct vchiq_dequeue_message *args)
+{
+	struct user_service *user_service;
+	struct vchiq_service *service;
+	struct vchiq_header *header;
+	int ret;
+
+	DEBUG_INITIALISE(g_state.local)
+	DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
+	service = find_service_for_instance(instance, args->handle);
+	if (!service)
+		return -EINVAL;
+
+	user_service = (struct user_service *)service->base.userdata;
+	if (user_service->is_vchi == 0) {
+		ret = -EINVAL;
+		goto out;
+	}
+
+	spin_lock(&msg_queue_spinlock);
+	if (user_service->msg_remove == user_service->msg_insert) {
+		if (!args->blocking) {
+			spin_unlock(&msg_queue_spinlock);
+			DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
+			ret = -EWOULDBLOCK;
+			goto out;
+		}
+		user_service->dequeue_pending = 1;
+		ret = 0;
+		do {
+			spin_unlock(&msg_queue_spinlock);
+			DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
+			if (wait_for_completion_interruptible(
+				&user_service->insert_event)) {
+				vchiq_log_info(vchiq_arm_log_level,
+					"DEQUEUE_MESSAGE interrupted");
+				ret = -EINTR;
+				break;
+			}
+			spin_lock(&msg_queue_spinlock);
+		} while (user_service->msg_remove == user_service->msg_insert);
+
+		if (ret)
+			goto out;
+	}
+
+	if (WARN_ON_ONCE((int)(user_service->msg_insert -
+			 user_service->msg_remove) < 0)) {
+		spin_unlock(&msg_queue_spinlock);
+		ret = -EINVAL;
+		goto out;
+	}
+
+	header = user_service->msg_queue[user_service->msg_remove &
+		(MSG_QUEUE_SIZE - 1)];
+	user_service->msg_remove++;
+	spin_unlock(&msg_queue_spinlock);
+
+	complete(&user_service->remove_event);
+	if (!header) {
+		ret = -ENOTCONN;
+	} else if (header->size <= args->bufsize) {
+		/* Copy to user space if msgbuf is not NULL */
+		if (!args->buf || (copy_to_user(args->buf,
+					header->data, header->size) == 0)) {
+			ret = header->size;
+			vchiq_release_message(service->handle, header);
+		} else {
+			ret = -EFAULT;
+		}
+	} else {
+		vchiq_log_error(vchiq_arm_log_level,
+			"header %pK: bufsize %x < size %x",
+			header, args->bufsize, header->size);
+		WARN(1, "invalid size\n");
+		ret = -EMSGSIZE;
+	}
+	DEBUG_TRACE(DEQUEUE_MESSAGE_LINE);
+out:
+	vchiq_service_put(service);
+	return ret;
+}
+
+static int vchiq_irq_queue_bulk_tx_rx(struct vchiq_instance *instance,
+				      struct vchiq_queue_bulk_transfer *args,
+				      enum vchiq_bulk_dir dir,
+				      enum vchiq_bulk_mode __user *mode)
+{
+	struct vchiq_service *service;
+	struct bulk_waiter_node *waiter = NULL;
+	bool found = false;
+	void *userdata;
+	int status = 0;
+	int ret;
+
+	service = find_service_for_instance(instance, args->handle);
+	if (!service)
+		return -EINVAL;
+
+	if (args->mode == VCHIQ_BULK_MODE_BLOCKING) {
+		waiter = kzalloc(sizeof(*waiter), GFP_KERNEL);
+		if (!waiter) {
+			ret = -ENOMEM;
+			goto out;
+		}
+
+		userdata = &waiter->bulk_waiter;
+	} else if (args->mode == VCHIQ_BULK_MODE_WAITING) {
+		mutex_lock(&instance->bulk_waiter_list_mutex);
+		list_for_each_entry(waiter, &instance->bulk_waiter_list,
+				    list) {
+			if (waiter->pid == current->pid) {
+				list_del(&waiter->list);
+				found = true;
+				break;
+			}
+		}
+		mutex_unlock(&instance->bulk_waiter_list_mutex);
+		if (!found) {
+			vchiq_log_error(vchiq_arm_log_level,
+				"no bulk_waiter found for pid %d",
+				current->pid);
+			ret = -ESRCH;
+			goto out;
+		}
+		vchiq_log_info(vchiq_arm_log_level,
+			"found bulk_waiter %pK for pid %d", waiter,
+			current->pid);
+		userdata = &waiter->bulk_waiter;
+	} else {
+		userdata = args->userdata;
+	}
+
+	status = vchiq_bulk_transfer(args->handle, NULL, args->data, args->size,
+				     userdata, args->mode, dir);
+
+	if (!waiter) {
+		ret = 0;
+		goto out;
+	}
+
+	if ((status != VCHIQ_RETRY) || fatal_signal_pending(current) ||
+		!waiter->bulk_waiter.bulk) {
+		if (waiter->bulk_waiter.bulk) {
+			/* Cancel the signal when the transfer completes. */
+			spin_lock(&bulk_waiter_spinlock);
+			waiter->bulk_waiter.bulk->userdata = NULL;
+			spin_unlock(&bulk_waiter_spinlock);
+		}
+		kfree(waiter);
+		ret = 0;
+	} else {
+		const enum vchiq_bulk_mode mode_waiting =
+			VCHIQ_BULK_MODE_WAITING;
+		waiter->pid = current->pid;
+		mutex_lock(&instance->bulk_waiter_list_mutex);
+		list_add(&waiter->list, &instance->bulk_waiter_list);
+		mutex_unlock(&instance->bulk_waiter_list_mutex);
+		vchiq_log_info(vchiq_arm_log_level,
+			"saved bulk_waiter %pK for pid %d",
+			waiter, current->pid);
+
+		ret = put_user(mode_waiting, mode);
+	}
+out:
+	vchiq_service_put(service);
+	if (ret)
+		return ret;
+	else if (status == VCHIQ_ERROR)
+		return -EIO;
+	else if (status == VCHIQ_RETRY)
+		return -EINTR;
+	return 0;
+}
+
+/* read a user pointer value from an array pointers in user space */
+static inline int vchiq_get_user_ptr(void __user **buf, void __user *ubuf, int index)
+{
+	int ret;
+
+	if (in_compat_syscall()) {
+		compat_uptr_t ptr32;
+		compat_uptr_t __user *uptr = ubuf;
+
+		ret = get_user(ptr32, uptr + index);
+		if (ret)
+			return ret;
+
+		*buf = compat_ptr(ptr32);
+	} else {
+		uintptr_t ptr, __user *uptr = ubuf;
+
+		ret = get_user(ptr, uptr + index);
+
+		if (ret)
+			return ret;
+
+		*buf = (void __user *)ptr;
+	}
+
+	return 0;
+}
+
+struct vchiq_completion_data32 {
+	enum vchiq_reason reason;
+	compat_uptr_t header;
+	compat_uptr_t service_userdata;
+	compat_uptr_t bulk_userdata;
+};
+
+static int vchiq_put_completion(struct vchiq_completion_data __user *buf,
+				struct vchiq_completion_data *completion,
+				int index)
+{
+	struct vchiq_completion_data32 __user *buf32 = (void __user *)buf;
+
+	if (in_compat_syscall()) {
+		struct vchiq_completion_data32 tmp = {
+			.reason		  = completion->reason,
+			.header		  = ptr_to_compat(completion->header),
+			.service_userdata = ptr_to_compat(completion->service_userdata),
+			.bulk_userdata	  = ptr_to_compat(completion->bulk_userdata),
+		};
+		if (copy_to_user(&buf32[index], &tmp, sizeof(tmp)))
+			return -EFAULT;
+	} else {
+		if (copy_to_user(&buf[index], completion, sizeof(*completion)))
+			return -EFAULT;
+	}
+
+	return 0;
+}
+
+static int vchiq_ioc_await_completion(struct vchiq_instance *instance,
+				      struct vchiq_await_completion *args,
+				      int __user *msgbufcountp)
+{
+	int msgbufcount;
+	int remove;
+	int ret;
+
+	DEBUG_INITIALISE(g_state.local)
+
+	DEBUG_TRACE(AWAIT_COMPLETION_LINE);
+	if (!instance->connected) {
+		return -ENOTCONN;
+	}
+
+	mutex_lock(&instance->completion_mutex);
+
+	DEBUG_TRACE(AWAIT_COMPLETION_LINE);
+	while ((instance->completion_remove == instance->completion_insert)
+		&& !instance->closing) {
+		int rc;
+
+		DEBUG_TRACE(AWAIT_COMPLETION_LINE);
+		mutex_unlock(&instance->completion_mutex);
+		rc = wait_for_completion_interruptible(
+					&instance->insert_event);
+		mutex_lock(&instance->completion_mutex);
+		if (rc) {
+			DEBUG_TRACE(AWAIT_COMPLETION_LINE);
+			vchiq_log_info(vchiq_arm_log_level,
+				"AWAIT_COMPLETION interrupted");
+			ret = -EINTR;
+			goto out;
+		}
+	}
+	DEBUG_TRACE(AWAIT_COMPLETION_LINE);
+
+	msgbufcount = args->msgbufcount;
+	remove = instance->completion_remove;
+
+	for (ret = 0; ret < args->count; ret++) {
+		struct vchiq_completion_data_kernel *completion;
+		struct vchiq_completion_data user_completion;
+		struct vchiq_service *service;
+		struct user_service *user_service;
+		struct vchiq_header *header;
+
+		if (remove == instance->completion_insert)
+			break;
+
+		completion = &instance->completions[
+			remove & (MAX_COMPLETIONS - 1)];
+
+		/*
+		 * A read memory barrier is needed to stop
+		 * prefetch of a stale completion record
+		 */
+		rmb();
+
+		service = completion->service_userdata;
+		user_service = service->base.userdata;
+
+		memset(&user_completion, 0, sizeof(user_completion));
+		user_completion = (struct vchiq_completion_data) {
+			.reason = completion->reason,
+			.service_userdata = user_service->userdata,
+		};
+
+		header = completion->header;
+		if (header) {
+			void __user *msgbuf;
+			int msglen;
+
+			msglen = header->size + sizeof(struct vchiq_header);
+			/* This must be a VCHIQ-style service */
+			if (args->msgbufsize < msglen) {
+				vchiq_log_error(vchiq_arm_log_level,
+					"header %pK: msgbufsize %x < msglen %x",
+					header, args->msgbufsize, msglen);
+				WARN(1, "invalid message size\n");
+				if (ret == 0)
+					ret = -EMSGSIZE;
+				break;
+			}
+			if (msgbufcount <= 0)
+				/* Stall here for lack of a buffer for the message. */
+				break;
+			/* Get the pointer from user space */
+			msgbufcount--;
+			if (vchiq_get_user_ptr(&msgbuf, args->msgbufs,
+						msgbufcount)) {
+				if (ret == 0)
+					ret = -EFAULT;
+				break;
+			}
+
+			/* Copy the message to user space */
+			if (copy_to_user(msgbuf, header, msglen)) {
+				if (ret == 0)
+					ret = -EFAULT;
+				break;
+			}
+
+			/* Now it has been copied, the message can be released. */
+			vchiq_release_message(service->handle, header);
+
+			/* The completion must point to the msgbuf. */
+			user_completion.header = msgbuf;
+		}
+
+		if ((completion->reason == VCHIQ_SERVICE_CLOSED) &&
+		    !instance->use_close_delivered)
+			vchiq_service_put(service);
+
+		/*
+		 * FIXME: address space mismatch, does bulk_userdata
+		 * actually point to user or kernel memory?
+		 */
+		user_completion.bulk_userdata = completion->bulk_userdata;
+
+		if (vchiq_put_completion(args->buf, &user_completion, ret)) {
+			if (ret == 0)
+				ret = -EFAULT;
+			break;
+		}
+
+		/*
+		 * Ensure that the above copy has completed
+		 * before advancing the remove pointer.
+		 */
+		mb();
+		remove++;
+		instance->completion_remove = remove;
+	}
+
+	if (msgbufcount != args->msgbufcount) {
+		if (put_user(msgbufcount, msgbufcountp))
+			ret = -EFAULT;
+	}
+out:
+	if (ret)
+		complete(&instance->remove_event);
+	mutex_unlock(&instance->completion_mutex);
+	DEBUG_TRACE(AWAIT_COMPLETION_LINE);
+
+	return ret;
+}
+
+static long
+vchiq_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	struct vchiq_instance *instance = file->private_data;
+	enum vchiq_status status = VCHIQ_SUCCESS;
+	struct vchiq_service *service = NULL;
+	long ret = 0;
+	int i, rc;
+
+	vchiq_log_trace(vchiq_arm_log_level,
+		"%s - instance %pK, cmd %s, arg %lx",
+		__func__, instance,
+		((_IOC_TYPE(cmd) == VCHIQ_IOC_MAGIC) &&
+		(_IOC_NR(cmd) <= VCHIQ_IOC_MAX)) ?
+		ioctl_names[_IOC_NR(cmd)] : "<invalid>", arg);
+
+	switch (cmd) {
+	case VCHIQ_IOC_SHUTDOWN:
+		if (!instance->connected)
+			break;
+
+		/* Remove all services */
+		i = 0;
+		while ((service = next_service_by_instance(instance->state,
+			instance, &i))) {
+			status = vchiq_remove_service(service->handle);
+			vchiq_service_put(service);
+			if (status != VCHIQ_SUCCESS)
+				break;
+		}
+		service = NULL;
+
+		if (status == VCHIQ_SUCCESS) {
+			/* Wake the completion thread and ask it to exit */
+			instance->closing = 1;
+			complete(&instance->insert_event);
+		}
+
+		break;
+
+	case VCHIQ_IOC_CONNECT:
+		if (instance->connected) {
+			ret = -EINVAL;
+			break;
+		}
+		rc = mutex_lock_killable(&instance->state->mutex);
+		if (rc) {
+			vchiq_log_error(vchiq_arm_log_level,
+				"vchiq: connect: could not lock mutex for state %d: %d",
+				instance->state->id, rc);
+			ret = -EINTR;
+			break;
+		}
+		status = vchiq_connect_internal(instance->state, instance);
+		mutex_unlock(&instance->state->mutex);
+
+		if (status == VCHIQ_SUCCESS)
+			instance->connected = 1;
+		else
+			vchiq_log_error(vchiq_arm_log_level,
+				"vchiq: could not connect: %d", status);
+		break;
+
+	case VCHIQ_IOC_CREATE_SERVICE: {
+		struct vchiq_create_service __user *argp;
+		struct vchiq_create_service args;
+
+		argp = (void __user *)arg;
+		if (copy_from_user(&args, argp, sizeof(args))) {
+			ret = -EFAULT;
+			break;
+		}
+
+		ret = vchiq_ioc_create_service(instance, &args);
+		if (ret < 0)
+			break;
+
+		if (put_user(args.handle, &argp->handle)) {
+			vchiq_remove_service(args.handle);
+			ret = -EFAULT;
+		}
+	} break;
+
+	case VCHIQ_IOC_CLOSE_SERVICE:
+	case VCHIQ_IOC_REMOVE_SERVICE: {
+		unsigned int handle = (unsigned int)arg;
+		struct user_service *user_service;
+
+		service = find_service_for_instance(instance, handle);
+		if (!service) {
+			ret = -EINVAL;
+			break;
+		}
+
+		user_service = service->base.userdata;
+
+		/*
+		 * close_pending is false on first entry, and when the
+		 * wait in vchiq_close_service has been interrupted.
+		 */
+		if (!user_service->close_pending) {
+			status = (cmd == VCHIQ_IOC_CLOSE_SERVICE) ?
+				 vchiq_close_service(service->handle) :
+				 vchiq_remove_service(service->handle);
+			if (status != VCHIQ_SUCCESS)
+				break;
+		}
+
+		/*
+		 * close_pending is true once the underlying service
+		 * has been closed until the client library calls the
+		 * CLOSE_DELIVERED ioctl, signalling close_event.
+		 */
+		if (user_service->close_pending &&
+			wait_for_completion_interruptible(
+				&user_service->close_event))
+			status = VCHIQ_RETRY;
+		break;
+	}
+
+	case VCHIQ_IOC_USE_SERVICE:
+	case VCHIQ_IOC_RELEASE_SERVICE:	{
+		unsigned int handle = (unsigned int)arg;
+
+		service = find_service_for_instance(instance, handle);
+		if (service) {
+			ret = (cmd == VCHIQ_IOC_USE_SERVICE) ?
+				vchiq_use_service_internal(service) :
+				vchiq_release_service_internal(service);
+			if (ret) {
+				vchiq_log_error(vchiq_susp_log_level,
+					"%s: cmd %s returned error %ld for service %c%c%c%c:%03d",
+					__func__,
+					(cmd == VCHIQ_IOC_USE_SERVICE) ?
+						"VCHIQ_IOC_USE_SERVICE" :
+						"VCHIQ_IOC_RELEASE_SERVICE",
+					ret,
+					VCHIQ_FOURCC_AS_4CHARS(
+						service->base.fourcc),
+					service->client_id);
+			}
+		} else {
+			ret = -EINVAL;
+		}
+	} break;
+
+	case VCHIQ_IOC_QUEUE_MESSAGE: {
+		struct vchiq_queue_message args;
+
+		if (copy_from_user(&args, (const void __user *)arg,
+				   sizeof(args))) {
+			ret = -EFAULT;
+			break;
+		}
+
+		service = find_service_for_instance(instance, args.handle);
+
+		if (service && (args.count <= MAX_ELEMENTS)) {
+			/* Copy elements into kernel space */
+			struct vchiq_element elements[MAX_ELEMENTS];
+
+			if (copy_from_user(elements, args.elements,
+				args.count * sizeof(struct vchiq_element)) == 0)
+				ret = vchiq_ioc_queue_message(args.handle, elements,
+							      args.count);
+			else
+				ret = -EFAULT;
+		} else {
+			ret = -EINVAL;
+		}
+	} break;
+
+	case VCHIQ_IOC_QUEUE_BULK_TRANSMIT:
+	case VCHIQ_IOC_QUEUE_BULK_RECEIVE: {
+		struct vchiq_queue_bulk_transfer args;
+		struct vchiq_queue_bulk_transfer __user *argp;
+
+		enum vchiq_bulk_dir dir =
+			(cmd == VCHIQ_IOC_QUEUE_BULK_TRANSMIT) ?
+			VCHIQ_BULK_TRANSMIT : VCHIQ_BULK_RECEIVE;
+
+		argp = (void __user *)arg;
+		if (copy_from_user(&args, argp, sizeof(args))) {
+			ret = -EFAULT;
+			break;
+		}
+
+		ret = vchiq_irq_queue_bulk_tx_rx(instance, &args,
+						 dir, &argp->mode);
+	} break;
+
+	case VCHIQ_IOC_AWAIT_COMPLETION: {
+		struct vchiq_await_completion args;
+		struct vchiq_await_completion __user *argp;
+
+		argp = (void __user *)arg;
+		if (copy_from_user(&args, argp, sizeof(args))) {
+			ret = -EFAULT;
+			break;
+		}
+
+		ret = vchiq_ioc_await_completion(instance, &args,
+						 &argp->msgbufcount);
+	} break;
+
+	case VCHIQ_IOC_DEQUEUE_MESSAGE: {
+		struct vchiq_dequeue_message args;
+
+		if (copy_from_user(&args, (const void __user *)arg,
+				   sizeof(args))) {
+			ret = -EFAULT;
+			break;
+		}
+
+		ret = vchiq_ioc_dequeue_message(instance, &args);
+	} break;
+
+	case VCHIQ_IOC_GET_CLIENT_ID: {
+		unsigned int handle = (unsigned int)arg;
+
+		ret = vchiq_get_client_id(handle);
+	} break;
+
+	case VCHIQ_IOC_GET_CONFIG: {
+		struct vchiq_get_config args;
+		struct vchiq_config config;
+
+		if (copy_from_user(&args, (const void __user *)arg,
+				   sizeof(args))) {
+			ret = -EFAULT;
+			break;
+		}
+		if (args.config_size > sizeof(config)) {
+			ret = -EINVAL;
+			break;
+		}
+
+		vchiq_get_config(&config);
+		if (copy_to_user(args.pconfig, &config, args.config_size)) {
+			ret = -EFAULT;
+			break;
+		}
+	} break;
+
+	case VCHIQ_IOC_SET_SERVICE_OPTION: {
+		struct vchiq_set_service_option args;
+
+		if (copy_from_user(&args, (const void __user *)arg,
+				   sizeof(args))) {
+			ret = -EFAULT;
+			break;
+		}
+
+		service = find_service_for_instance(instance, args.handle);
+		if (!service) {
+			ret = -EINVAL;
+			break;
+		}
+
+		ret = vchiq_set_service_option(args.handle, args.option,
+					       args.value);
+	} break;
+
+	case VCHIQ_IOC_LIB_VERSION: {
+		unsigned int lib_version = (unsigned int)arg;
+
+		if (lib_version < VCHIQ_VERSION_MIN)
+			ret = -EINVAL;
+		else if (lib_version >= VCHIQ_VERSION_CLOSE_DELIVERED)
+			instance->use_close_delivered = 1;
+	} break;
+
+	case VCHIQ_IOC_CLOSE_DELIVERED: {
+		unsigned int handle = (unsigned int)arg;
+
+		service = find_closed_service_for_instance(instance, handle);
+		if (service) {
+			struct user_service *user_service =
+				(struct user_service *)service->base.userdata;
+			close_delivered(user_service);
+		} else {
+			ret = -EINVAL;
+		}
+	} break;
+
+	default:
+		ret = -ENOTTY;
+		break;
+	}
+
+	if (service)
+		vchiq_service_put(service);
+
+	if (ret == 0) {
+		if (status == VCHIQ_ERROR)
+			ret = -EIO;
+		else if (status == VCHIQ_RETRY)
+			ret = -EINTR;
+	}
+
+	if ((status == VCHIQ_SUCCESS) && (ret < 0) && (ret != -EINTR) &&
+		(ret != -EWOULDBLOCK))
+		vchiq_log_info(vchiq_arm_log_level,
+			"  ioctl instance %pK, cmd %s -> status %d, %ld",
+			instance,
+			(_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
+				ioctl_names[_IOC_NR(cmd)] :
+				"<invalid>",
+			status, ret);
+	else
+		vchiq_log_trace(vchiq_arm_log_level,
+			"  ioctl instance %pK, cmd %s -> status %d, %ld",
+			instance,
+			(_IOC_NR(cmd) <= VCHIQ_IOC_MAX) ?
+				ioctl_names[_IOC_NR(cmd)] :
+				"<invalid>",
+			status, ret);
+
+	return ret;
+}
+
+#if defined(CONFIG_COMPAT)
+
+struct vchiq_service_params32 {
+	int fourcc;
+	compat_uptr_t callback;
+	compat_uptr_t userdata;
+	short version; /* Increment for non-trivial changes */
+	short version_min; /* Update for incompatible changes */
+};
+
+struct vchiq_create_service32 {
+	struct vchiq_service_params32 params;
+	int is_open;
+	int is_vchi;
+	unsigned int handle; /* OUT */
+};
+
+#define VCHIQ_IOC_CREATE_SERVICE32 \
+	_IOWR(VCHIQ_IOC_MAGIC, 2, struct vchiq_create_service32)
+
+static long
+vchiq_compat_ioctl_create_service(struct file *file, unsigned int cmd,
+				  struct vchiq_create_service32 __user *ptrargs32)
+{
+	struct vchiq_create_service args;
+	struct vchiq_create_service32 args32;
+	long ret;
+
+	if (copy_from_user(&args32, ptrargs32, sizeof(args32)))
+		return -EFAULT;
+
+	args = (struct vchiq_create_service) {
+		.params = {
+			.fourcc	     = args32.params.fourcc,
+			.callback    = compat_ptr(args32.params.callback),
+			.userdata    = compat_ptr(args32.params.userdata),
+			.version     = args32.params.version,
+			.version_min = args32.params.version_min,
+		},
+		.is_open = args32.is_open,
+		.is_vchi = args32.is_vchi,
+		.handle  = args32.handle,
+	};
+
+	ret = vchiq_ioc_create_service(file->private_data, &args);
+	if (ret < 0)
+		return ret;
+
+	if (put_user(args.handle, &ptrargs32->handle)) {
+		vchiq_remove_service(args.handle);
+		return -EFAULT;
+	}
+
+	return 0;
+}
+
+struct vchiq_element32 {
+	compat_uptr_t data;
+	unsigned int size;
+};
+
+struct vchiq_queue_message32 {
+	unsigned int handle;
+	unsigned int count;
+	compat_uptr_t elements;
+};
+
+#define VCHIQ_IOC_QUEUE_MESSAGE32 \
+	_IOW(VCHIQ_IOC_MAGIC,  4, struct vchiq_queue_message32)
+
+static long
+vchiq_compat_ioctl_queue_message(struct file *file,
+				 unsigned int cmd,
+				 struct vchiq_queue_message32 __user *arg)
+{
+	struct vchiq_queue_message args;
+	struct vchiq_queue_message32 args32;
+	struct vchiq_service *service;
+	int ret;
+
+	if (copy_from_user(&args32, arg, sizeof(args32)))
+		return -EFAULT;
+
+	args = (struct vchiq_queue_message) {
+		.handle   = args32.handle,
+		.count    = args32.count,
+		.elements = compat_ptr(args32.elements),
+	};
+
+	if (args32.count > MAX_ELEMENTS)
+		return -EINVAL;
+
+	service = find_service_for_instance(file->private_data, args.handle);
+	if (!service)
+		return -EINVAL;
+
+	if (args32.elements && args32.count) {
+		struct vchiq_element32 element32[MAX_ELEMENTS];
+		struct vchiq_element elements[MAX_ELEMENTS];
+		unsigned int count;
+
+		if (copy_from_user(&element32, args.elements,
+				   sizeof(element32))) {
+			vchiq_service_put(service);
+			return -EFAULT;
+		}
+
+		for (count = 0; count < args32.count; count++) {
+			elements[count].data =
+				compat_ptr(element32[count].data);
+			elements[count].size = element32[count].size;
+		}
+		ret = vchiq_ioc_queue_message(args.handle, elements,
+					      args.count);
+	} else {
+		ret = -EINVAL;
+	}
+	vchiq_service_put(service);
+
+	return ret;
+}
+
+struct vchiq_queue_bulk_transfer32 {
+	unsigned int handle;
+	compat_uptr_t data;
+	unsigned int size;
+	compat_uptr_t userdata;
+	enum vchiq_bulk_mode mode;
+};
+
+#define VCHIQ_IOC_QUEUE_BULK_TRANSMIT32 \
+	_IOWR(VCHIQ_IOC_MAGIC, 5, struct vchiq_queue_bulk_transfer32)
+#define VCHIQ_IOC_QUEUE_BULK_RECEIVE32 \
+	_IOWR(VCHIQ_IOC_MAGIC, 6, struct vchiq_queue_bulk_transfer32)
+
+static long
+vchiq_compat_ioctl_queue_bulk(struct file *file,
+			      unsigned int cmd,
+			      struct vchiq_queue_bulk_transfer32 __user *argp)
+{
+	struct vchiq_queue_bulk_transfer32 args32;
+	struct vchiq_queue_bulk_transfer args;
+	enum vchiq_bulk_dir dir = (cmd == VCHIQ_IOC_QUEUE_BULK_TRANSMIT32) ?
+				  VCHIQ_BULK_TRANSMIT : VCHIQ_BULK_RECEIVE;
+
+	if (copy_from_user(&args32, argp, sizeof(args32)))
+		return -EFAULT;
+
+	args = (struct vchiq_queue_bulk_transfer) {
+		.handle   = args32.handle,
+		.data	  = compat_ptr(args32.data),
+		.size	  = args32.size,
+		.userdata = compat_ptr(args32.userdata),
+		.mode	  = args32.mode,
+	};
+
+	return vchiq_irq_queue_bulk_tx_rx(file->private_data, &args,
+					  dir, &argp->mode);
+}
+
+struct vchiq_await_completion32 {
+	unsigned int count;
+	compat_uptr_t buf;
+	unsigned int msgbufsize;
+	unsigned int msgbufcount; /* IN/OUT */
+	compat_uptr_t msgbufs;
+};
+
+#define VCHIQ_IOC_AWAIT_COMPLETION32 \
+	_IOWR(VCHIQ_IOC_MAGIC, 7, struct vchiq_await_completion32)
+
+static long
+vchiq_compat_ioctl_await_completion(struct file *file,
+				    unsigned int cmd,
+				    struct vchiq_await_completion32 __user *argp)
+{
+	struct vchiq_await_completion args;
+	struct vchiq_await_completion32 args32;
+
+	if (copy_from_user(&args32, argp, sizeof(args32)))
+		return -EFAULT;
+
+	args = (struct vchiq_await_completion) {
+		.count		= args32.count,
+		.buf		= compat_ptr(args32.buf),
+		.msgbufsize	= args32.msgbufsize,
+		.msgbufcount	= args32.msgbufcount,
+		.msgbufs	= compat_ptr(args32.msgbufs),
+	};
+
+	return vchiq_ioc_await_completion(file->private_data, &args,
+					  &argp->msgbufcount);
+}
+
+struct vchiq_dequeue_message32 {
+	unsigned int handle;
+	int blocking;
+	unsigned int bufsize;
+	compat_uptr_t buf;
+};
+
+#define VCHIQ_IOC_DEQUEUE_MESSAGE32 \
+	_IOWR(VCHIQ_IOC_MAGIC, 8, struct vchiq_dequeue_message32)
+
+static long
+vchiq_compat_ioctl_dequeue_message(struct file *file,
+				   unsigned int cmd,
+				   struct vchiq_dequeue_message32 __user *arg)
+{
+	struct vchiq_dequeue_message32 args32;
+	struct vchiq_dequeue_message args;
+
+	if (copy_from_user(&args32, arg, sizeof(args32)))
+		return -EFAULT;
+
+	args = (struct vchiq_dequeue_message) {
+		.handle		= args32.handle,
+		.blocking	= args32.blocking,
+		.bufsize	= args32.bufsize,
+		.buf		= compat_ptr(args32.buf),
+	};
+
+	return vchiq_ioc_dequeue_message(file->private_data, &args);
+}
+
+struct vchiq_get_config32 {
+	unsigned int config_size;
+	compat_uptr_t pconfig;
+};
+
+#define VCHIQ_IOC_GET_CONFIG32 \
+	_IOWR(VCHIQ_IOC_MAGIC, 10, struct vchiq_get_config32)
+
+static long
+vchiq_compat_ioctl_get_config(struct file *file,
+			      unsigned int cmd,
+			      struct vchiq_get_config32 __user *arg)
+{
+	struct vchiq_get_config32 args32;
+	struct vchiq_config config;
+	void __user *ptr;
+
+	if (copy_from_user(&args32, arg, sizeof(args32)))
+		return -EFAULT;
+	if (args32.config_size > sizeof(config))
+		return -EINVAL;
+
+	vchiq_get_config(&config);
+	ptr = compat_ptr(args32.pconfig);
+	if (copy_to_user(ptr, &config, args32.config_size))
+		return -EFAULT;
+
+	return 0;
+}
+
+static long
+vchiq_compat_ioctl(struct file *file, unsigned int cmd, unsigned long arg)
+{
+	void __user *argp = compat_ptr(arg);
+
+	switch (cmd) {
+	case VCHIQ_IOC_CREATE_SERVICE32:
+		return vchiq_compat_ioctl_create_service(file, cmd, argp);
+	case VCHIQ_IOC_QUEUE_MESSAGE32:
+		return vchiq_compat_ioctl_queue_message(file, cmd, argp);
+	case VCHIQ_IOC_QUEUE_BULK_TRANSMIT32:
+	case VCHIQ_IOC_QUEUE_BULK_RECEIVE32:
+		return vchiq_compat_ioctl_queue_bulk(file, cmd, argp);
+	case VCHIQ_IOC_AWAIT_COMPLETION32:
+		return vchiq_compat_ioctl_await_completion(file, cmd, argp);
+	case VCHIQ_IOC_DEQUEUE_MESSAGE32:
+		return vchiq_compat_ioctl_dequeue_message(file, cmd, argp);
+	case VCHIQ_IOC_GET_CONFIG32:
+		return vchiq_compat_ioctl_get_config(file, cmd, argp);
+	default:
+		return vchiq_ioctl(file, cmd, (unsigned long)argp);
+	}
+}
+
+#endif
+
+static int vchiq_open(struct inode *inode, struct file *file)
+{
+	struct vchiq_state *state = vchiq_get_state();
+	struct vchiq_instance *instance;
+
+	vchiq_log_info(vchiq_arm_log_level, "vchiq_open");
+
+	if (!state) {
+		vchiq_log_error(vchiq_arm_log_level,
+				"vchiq has no connection to VideoCore");
+		return -ENOTCONN;
+	}
+
+	instance = kzalloc(sizeof(*instance), GFP_KERNEL);
+	if (!instance)
+		return -ENOMEM;
+
+	instance->state = state;
+	instance->pid = current->tgid;
+
+	vchiq_debugfs_add_instance(instance);
+
+	init_completion(&instance->insert_event);
+	init_completion(&instance->remove_event);
+	mutex_init(&instance->completion_mutex);
+	mutex_init(&instance->bulk_waiter_list_mutex);
+	INIT_LIST_HEAD(&instance->bulk_waiter_list);
+
+	file->private_data = instance;
+
+	return 0;
+}
+
+static int vchiq_release(struct inode *inode, struct file *file)
+{
+	struct vchiq_instance *instance = file->private_data;
+	struct vchiq_state *state = vchiq_get_state();
+	struct vchiq_service *service;
+	int ret = 0;
+	int i;
+
+	vchiq_log_info(vchiq_arm_log_level, "%s: instance=%lx", __func__,
+		       (unsigned long)instance);
+
+	if (!state) {
+		ret = -EPERM;
+		goto out;
+	}
+
+	/* Ensure videocore is awake to allow termination. */
+	vchiq_use_internal(instance->state, NULL, USE_TYPE_VCHIQ);
+
+	mutex_lock(&instance->completion_mutex);
+
+	/* Wake the completion thread and ask it to exit */
+	instance->closing = 1;
+	complete(&instance->insert_event);
+
+	mutex_unlock(&instance->completion_mutex);
+
+	/* Wake the slot handler if the completion queue is full. */
+	complete(&instance->remove_event);
+
+	/* Mark all services for termination... */
+	i = 0;
+	while ((service = next_service_by_instance(state, instance, &i))) {
+		struct user_service *user_service = service->base.userdata;
+
+		/* Wake the slot handler if the msg queue is full. */
+		complete(&user_service->remove_event);
+
+		vchiq_terminate_service_internal(service);
+		vchiq_service_put(service);
+	}
+
+	/* ...and wait for them to die */
+	i = 0;
+	while ((service = next_service_by_instance(state, instance, &i))) {
+		struct user_service *user_service = service->base.userdata;
+
+		wait_for_completion(&service->remove_event);
+
+		if (WARN_ON(service->srvstate != VCHIQ_SRVSTATE_FREE)) {
+			vchiq_service_put(service);
+			break;
+		}
+
+		spin_lock(&msg_queue_spinlock);
+
+		while (user_service->msg_remove != user_service->msg_insert) {
+			struct vchiq_header *header;
+			int m = user_service->msg_remove & (MSG_QUEUE_SIZE - 1);
+
+			header = user_service->msg_queue[m];
+			user_service->msg_remove++;
+			spin_unlock(&msg_queue_spinlock);
+
+			if (header)
+				vchiq_release_message(service->handle, header);
+			spin_lock(&msg_queue_spinlock);
+		}
+
+		spin_unlock(&msg_queue_spinlock);
+
+		vchiq_service_put(service);
+	}
+
+	/* Release any closed services */
+	while (instance->completion_remove != instance->completion_insert) {
+		struct vchiq_completion_data_kernel *completion;
+		struct vchiq_service *service;
+
+		completion = &instance->completions[
+			instance->completion_remove & (MAX_COMPLETIONS - 1)];
+		service = completion->service_userdata;
+		if (completion->reason == VCHIQ_SERVICE_CLOSED) {
+			struct user_service *user_service =
+							service->base.userdata;
+
+			/* Wake any blocked user-thread */
+			if (instance->use_close_delivered)
+				complete(&user_service->close_event);
+			vchiq_service_put(service);
+		}
+		instance->completion_remove++;
+	}
+
+	/* Release the PEER service count. */
+	vchiq_release_internal(instance->state, NULL);
+
+	free_bulk_waiter(instance);
+
+	vchiq_debugfs_remove_instance(instance);
+
+	kfree(instance);
+	file->private_data = NULL;
+
+out:
+	return ret;
+}
+
+static ssize_t
+vchiq_read(struct file *file, char __user *buf, size_t count, loff_t *ppos)
+{
+	struct dump_context context;
+	int err;
+
+	context.buf = buf;
+	context.actual = 0;
+	context.space = count;
+	context.offset = *ppos;
+
+	err = vchiq_dump_state(&context, &g_state);
+	if (err)
+		return err;
+
+	*ppos += context.actual;
+
+	return context.actual;
+}
+
+static const struct file_operations
+vchiq_fops = {
+	.owner = THIS_MODULE,
+	.unlocked_ioctl = vchiq_ioctl,
+#if defined(CONFIG_COMPAT)
+	.compat_ioctl = vchiq_compat_ioctl,
+#endif
+	.open = vchiq_open,
+	.release = vchiq_release,
+	.read = vchiq_read
+};
+
+/**
+ *	vchiq_register_chrdev - Register the char driver for vchiq
+ *				and create the necessary class and
+ *				device files in userspace.
+ *	@parent		The parent of the char device.
+ *
+ *	Returns 0 on success else returns the error code.
+ */
+int vchiq_register_chrdev(struct device *parent)
+{
+	struct device *vchiq_dev;
+	int ret;
+
+	vchiq_class = class_create(THIS_MODULE, DEVICE_NAME);
+	if (IS_ERR(vchiq_class)) {
+		pr_err("Failed to create vchiq class\n");
+		ret = PTR_ERR(vchiq_class);
+		goto error_exit;
+	}
+
+	ret = alloc_chrdev_region(&vchiq_devid, 0, 1, DEVICE_NAME);
+	if (ret) {
+		pr_err("vchiq: Failed to allocate vchiq's chrdev region\n");
+		goto alloc_region_error;
+	}
+
+	cdev_init(&vchiq_cdev, &vchiq_fops);
+	vchiq_cdev.owner = THIS_MODULE;
+	ret = cdev_add(&vchiq_cdev, vchiq_devid, 1);
+	if (ret) {
+		vchiq_log_error(vchiq_arm_log_level,
+				"Unable to register vchiq char device");
+		goto cdev_add_error;
+	}
+
+	vchiq_dev = device_create(vchiq_class, parent, vchiq_devid, NULL,
+				  DEVICE_NAME);
+	if (IS_ERR(vchiq_dev)) {
+		vchiq_log_error(vchiq_arm_log_level,
+				"Failed to create vchiq char device node");
+		ret = PTR_ERR(vchiq_dev);
+		goto device_create_error;
+	}
+
+	vchiq_log_info(vchiq_arm_log_level,
+		       "vchiq char dev initialised successfully - device %d.%d",
+			MAJOR(vchiq_devid), MINOR(vchiq_devid));
+
+	return 0;
+
+device_create_error:
+	cdev_del(&vchiq_cdev);
+
+cdev_add_error:
+	unregister_chrdev_region(vchiq_devid, 1);
+
+alloc_region_error:
+	class_destroy(vchiq_class);
+
+error_exit:
+	return ret;
+}
+
+/**
+ *	vchiq_deregister_chrdev	- Deregister and cleanup the vchiq char
+ *				  driver and device files
+ */
+void vchiq_deregister_chrdev(void)
+{
+	device_destroy(vchiq_class, vchiq_devid);
+	cdev_del(&vchiq_cdev);
+	unregister_chrdev_region(vchiq_devid, 1);
+	class_destroy(vchiq_class);
+}
-- 
2.25.1