diff --git a/drivers/s390/cio/device_ops.c b/drivers/s390/cio/device_ops.c index ccecf6b9504e8..5a411595347b5 100644 --- a/drivers/s390/cio/device_ops.c +++ b/drivers/s390/cio/device_ops.c @@ -717,13 +717,23 @@ EXPORT_SYMBOL_GPL(ccw_device_get_schid); */ void *ccw_device_dma_zalloc(struct ccw_device *cdev, size_t size) { - return cio_gp_dma_zalloc(cdev->private->dma_pool, &cdev->dev, size); + void *addr; + + if (!get_device(&cdev->dev)) + return NULL; + addr = cio_gp_dma_zalloc(cdev->private->dma_pool, &cdev->dev, size); + if (IS_ERR_OR_NULL(addr)) + put_device(&cdev->dev); + return addr; } EXPORT_SYMBOL(ccw_device_dma_zalloc); void ccw_device_dma_free(struct ccw_device *cdev, void *cpu_addr, size_t size) { + if (!cpu_addr) + return; cio_gp_dma_free(cdev->private->dma_pool, cpu_addr, size); + put_device(&cdev->dev); } EXPORT_SYMBOL(ccw_device_dma_free);