The virtio-pmem request object stores wait queues, flags, and list pointers next to buffers mapped for virtqueue DMA. The response buffer is mapped DMA_FROM_DEVICE, so non-coherent DMA invalidation must not share a cache line with CPU-owned fields.
Keep the request buffer outside the DMA-from-device group and wrap only the response buffer with __dma_from_device_group_begin/end. Signed-off-by: Li Chen <[email protected]> --- Changes in v6: - New patch. drivers/nvdimm/virtio_pmem.h | 8 ++++++-- 1 file changed, 6 insertions(+), 2 deletions(-) diff --git a/drivers/nvdimm/virtio_pmem.h b/drivers/nvdimm/virtio_pmem.h index 1017e498c9b4c..23bff40249c1b 100644 --- a/drivers/nvdimm/virtio_pmem.h +++ b/drivers/nvdimm/virtio_pmem.h @@ -10,6 +10,7 @@ #ifndef _LINUX_VIRTIO_PMEM_H #define _LINUX_VIRTIO_PMEM_H +#include <linux/dma-mapping.h> #include <linux/module.h> #include <uapi/linux/virtio_pmem.h> #include <linux/kref.h> @@ -19,8 +20,6 @@ struct virtio_pmem_request { struct kref kref; - struct virtio_pmem_req req; - struct virtio_pmem_resp resp; /* Wait queue to process deferred work after ack from host */ wait_queue_head_t host_acked; @@ -30,6 +29,11 @@ struct virtio_pmem_request { wait_queue_head_t wq_buf; bool wq_buf_avail; struct list_head list; + + struct virtio_pmem_req req; + __dma_from_device_group_begin(resp); + struct virtio_pmem_resp resp; + __dma_from_device_group_end(resp); }; struct virtio_pmem { -- 2.52.0
