Re: [PATCH 4/7] staging: vchiq_core: Factor out bulk transfer for (no/)callback mode

[Laurent Pinchart <laurent.pinchart@ideasonboard.com>]

Hi Umang,

Thank you for the patch.

On Fri, Aug 23, 2024 at 08:44:24PM +0530, Umang Jain wrote:
> Factor out bulk transfer for VCHIQ_BULK_MODE_NOCALLBACK and
> VCHIQ_BULK_MODE_CALLBACK mode into a separate dedicated function
> bulk_xfer_callback_interruptible(). It is suffixed by "_interruptible"
> to denote that it can be interrupted and -EAGAIN can be returned. It
> would be up to the users of the function to retry the call in those cases.
> 
> bulk_xfer_callback_interruptible() also takes in 'mode' parameter to
> differentiate between VCHIQ_BULK_MODE_NOCALLBACK and
> VCHIQ_BULK_MODE_CALLBACK, which then is directly passed to
> vchiq_bulk_xfer_queue_msg_interruptible() inside the function.
> 
> Adjust the calls to vchiq-dev.c ioctl interface and vchiq_arm.c
> for the respective bulk transfers.
> 
> Signed-off-by: Umang Jain <umang.jain@ideasonboard.com>
> ---
>  .../vc04_services/interface/vchiq_arm/vchiq_arm.c  | 15 ++++----
>  .../vc04_services/interface/vchiq_arm/vchiq_core.c | 40 ++++++++++++++++++++++
>  .../vc04_services/interface/vchiq_arm/vchiq_core.h |  6 ++++
>  .../vc04_services/interface/vchiq_arm/vchiq_dev.c  |  6 ++++
>  4 files changed, 60 insertions(+), 7 deletions(-)
> 
> 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 e9b9c76381dc..5210ce8d269e 100644
> --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
> +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_arm.c
> @@ -857,10 +857,10 @@ vchiq_bulk_transmit(struct vchiq_instance *instance, unsigned int handle, const
>  		switch (mode) {
>  		case VCHIQ_BULK_MODE_NOCALLBACK:
>  		case VCHIQ_BULK_MODE_CALLBACK:
> -			ret = vchiq_bulk_transfer(instance, handle,
> -						  (void *)data, NULL,
> -						  size, userdata, mode,
> -						  VCHIQ_BULK_TRANSMIT);
> +			ret = bulk_xfer_callback_interruptible(instance, handle,
> +							       (void *)data, NULL,
> +							       size, mode, userdata,
> +							       VCHIQ_BULK_TRANSMIT);
>  			break;
>  		case VCHIQ_BULK_MODE_BLOCKING:
>  			ret = vchiq_blocking_bulk_transfer(instance, handle, (void *)data, size,
> @@ -895,9 +895,10 @@ int vchiq_bulk_receive(struct vchiq_instance *instance, unsigned int handle,
>  		switch (mode) {
>  		case VCHIQ_BULK_MODE_NOCALLBACK:
>  		case VCHIQ_BULK_MODE_CALLBACK:
> -			ret = vchiq_bulk_transfer(instance, handle, data, NULL,
> -						  size, userdata,
> -						  mode, VCHIQ_BULK_RECEIVE);
> +			ret = bulk_xfer_callback_interruptible(instance, handle,
> +							       (void *)data, NULL,
> +							       size, mode, userdata,
> +							       VCHIQ_BULK_RECEIVE);
>  			break;
>  		case VCHIQ_BULK_MODE_BLOCKING:
>  			ret = vchiq_blocking_bulk_transfer(instance, handle, (void *)data, size,
> diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.c
> index 341a06997848..0606561fd3d0 100644
> --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.c
> +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.c
> @@ -3027,6 +3027,46 @@ bulk_xfer_blocking_interruptible(struct vchiq_instance *instance, unsigned int h
>  	return status;
>  }
>  
> +int
> +bulk_xfer_callback_interruptible(struct vchiq_instance *instance, unsigned int handle,

Please prefix the name of all functions with an appropriate driver
prefix, especially for functions that are not static.

> +				 void *offset, void __user *uoffset, int size,
> +				 enum vchiq_bulk_mode mode, void *userdata,
> +				 enum vchiq_bulk_dir dir)
> +{
> +	struct vchiq_service *service = find_service_by_handle(instance, handle);
> +	int status = -EINVAL;
> +
> +	if (!service)
> +		goto error_exit;
> +
> +	if (mode != VCHIQ_BULK_MODE_CALLBACK &&
> +	    mode != VCHIQ_BULK_MODE_NOCALLBACK)
> +		goto error_exit;
> +
> +	if (service->srvstate != VCHIQ_SRVSTATE_OPEN)
> +		goto error_exit;
> +
> +	if (!offset && !uoffset)
> +		goto error_exit;
> +
> +	if (vchiq_check_service(service))
> +		goto error_exit;
> +
> +	status = vchiq_bulk_xfer_queue_msg_interruptible(service, offset, uoffset,
> +							 size, userdata, mode, dir);
> +	if (status)
> +		goto error_exit;
> +
> +	vchiq_service_put(service);
> +
> +	return 0;
> +
> +error_exit:
> +	if (service)
> +		vchiq_service_put(service);
> +	return status;
> +}
> +
>  /*
>   * This function may be called by kernel threads or user threads.
>   * User threads may receive -EAGAIN to indicate that a signal has been
> diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.h b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.h
> index ff3559c3d1ba..8aaf3c9d3dbe 100644
> --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.h
> +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_core.h
> @@ -479,6 +479,12 @@ bulk_xfer_blocking_interruptible(struct vchiq_instance *instance, unsigned int h
>  				 void *offset, void __user *uoffset, int size,
>  				 void __user *userdata, enum vchiq_bulk_dir dir);
>  
> +extern int
> +bulk_xfer_callback_interruptible(struct vchiq_instance *instance, unsigned int handle,
> +				 void *offset, void __user *uoffset, int size,
> +				 enum vchiq_bulk_mode mode, void *userdata,
> +				 enum vchiq_bulk_dir dir);
> +
>  extern int
>  vchiq_bulk_transfer(struct vchiq_instance *instance, unsigned int handle, void *offset,
>  		    void __user *uoffset, int size, void *userdata, enum vchiq_bulk_mode mode,
> diff --git a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c
> index 1bff97ad28fa..7ecfcaa85569 100644
> --- a/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c
> +++ b/drivers/staging/vc04_services/interface/vchiq_arm/vchiq_dev.c
> @@ -336,6 +336,12 @@ static int vchiq_irq_queue_bulk_tx_rx(struct vchiq_instance *instance,
>  		goto bulk_transfer_handled;
>  	} else {
>  		userdata = args->userdata;
> +
> +		status = bulk_xfer_callback_interruptible(instance, args->handle,
> +							  NULL, args->data, args->size,
> +							  args->mode, userdata, dir);
> +
> +		goto bulk_transfer_handled;
>  	}
>  
>  	status = vchiq_bulk_transfer(instance, args->handle, NULL, args->data, args->size,
> 

-- 
Regards,

Laurent Pinchart