virtio_ring: Fix querying of maximum DMA mapping size for virtio device virtio_max_dma_size() returns the maximum DMA mapping size of the virtio device by querying dma_max_mapping_size() for the device when the DMA API is in use for the vring. Unfortunately, the device passed is initialised by register_virtio_device() and does not inherit the DMA configuration from its parent, resulting in SWIOTLB errors when bouncing is enabled and the default 256K mapping limit (IO_TLB_SEGSIZE) is not respected: | virtio-pci 0000:00:01.0: swiotlb buffer is full (sz: 294912 bytes), total 1024 (slots), used 725 (slots) Follow the pattern used elsewhere in the virtio_ring code when calling into the DMA layer and pass the parent device to dma_max_mapping_size() instead. Cc: Marc Zyngier <maz@kernel.org> Cc: Quentin Perret <qperret@google.com> Cc: "Michael S. Tsirkin" <mst@redhat.com> Cc: Jason Wang <jasowang@redhat.com> Signed-off-by: Will Deacon <will@kernel.org>
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c index 00f64f2..c294d04 100644 --- a/drivers/virtio/virtio_ring.c +++ b/drivers/virtio/virtio_ring.c
@@ -274,7 +274,7 @@ size_t virtio_max_dma_size(struct virtio_device *vdev) size_t max_segment_size = SIZE_MAX; if (vring_use_dma_api(vdev)) - max_segment_size = dma_max_mapping_size(&vdev->dev); + max_segment_size = dma_max_mapping_size(vdev->dev.parent); return max_segment_size; }