In the process of dma sync, we involved whether virtio uses dma api. On
the other hand, it is also necessary to read vdev->dev.parent. So these
API has been introduced.
Signed-off-by: Xuan Zhuo <xuanzhuo@xxxxxxxxxxxxxxxxx>
---
drivers/virtio/virtio_ring.c | 61 ++++++++++++++++++++++++++++++++++++
include/linux/virtio.h | 8 +++++
2 files changed, 69 insertions(+)
diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 67eda7bc23ea..7b393133fd27 100644
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -3102,4 +3102,65 @@ void virtio_dma_unmap(struct device *dev, dma_addr_t dma, unsigned int length,
}
EXPORT_SYMBOL_GPL(virtio_dma_unmap);
+/**
+ * virtio_dma_need_sync - check dma address need sync
+ * @dev: virtio device
+ * @addr: DMA address
+ */
+bool virtio_dma_need_sync(struct device *dev, dma_addr_t addr)
+{
+ struct virtio_device *vdev = dev_to_virtio(dev);
+
+ if (!vring_use_dma_api(vdev))
+ return 0;
+
+ return dma_need_sync(vdev->dev.parent, addr);
+}
+EXPORT_SYMBOL_GPL(virtio_dma_need_sync);
+
+/**
+ * virtio_dma_sync_signle_range_for_cpu - dma sync for cpu
+ * @dev: virtio device
+ * @addr: DMA address
+ * @offset: DMA address offset
+ * @size: mem size for sync
+ * @dir: DMA direction
+ *
+ * Before calling this function, use virtio_dma_need_sync() to confirm that the
+ * DMA address really needs to be synchronized
+ */
+void virtio_dma_sync_signle_range_for_cpu(struct device *dev, dma_addr_t addr,
+ unsigned long offset, size_t size,
+ enum dma_data_direction dir)
+{
+ struct virtio_device *vdev = dev_to_virtio(dev);
+
+ dma_sync_single_range_for_cpu(vdev->dev.parent, addr, offset,
+ size, DMA_BIDIRECTIONAL);
+}
+EXPORT_SYMBOL_GPL(virtio_dma_sync_signle_range_for_cpu);
+
+/**
+ * virtio_dma_sync_signle_range_for_device - dma sync for device
+ * @dev: virtio device
+ * @addr: DMA address
+ * @offset: DMA address offset
+ * @size: mem size for sync
+ * @dir: DMA direction
+ *
+ * Before calling this function, use virtio_dma_need_sync() to confirm that the
+ * DMA address really needs to be synchronized
+ */
+void virtio_dma_sync_signle_range_for_device(struct device *dev,
+ dma_addr_t addr,
+ unsigned long offset, size_t size,
+ enum dma_data_direction dir)
+{
+ struct virtio_device *vdev = dev_to_virtio(dev);
+
+ dma_sync_single_range_for_device(vdev->dev.parent, addr, offset,
+ size, DMA_BIDIRECTIONAL);
+}
+EXPORT_SYMBOL_GPL(virtio_dma_sync_signle_range_for_device);
+
MODULE_LICENSE("GPL");
diff --git a/include/linux/virtio.h b/include/linux/virtio.h
index ce89126becc5..8c2fae318b0c 100644
--- a/include/linux/virtio.h
+++ b/include/linux/virtio.h
@@ -227,4 +227,12 @@ dma_addr_t virtio_dma_map(struct device *dev, void *addr, unsigned int length,
int virtio_dma_mapping_error(struct device *dev, dma_addr_t addr);
void virtio_dma_unmap(struct device *dev, dma_addr_t dma, unsigned int length,
enum dma_data_direction dir);
+bool virtio_dma_need_sync(struct device *dev, dma_addr_t addr);
+void virtio_dma_sync_signle_range_for_cpu(struct device *dev, dma_addr_t addr,
+ unsigned long offset, size_t size,
+ enum dma_data_direction dir);
+void virtio_dma_sync_signle_range_for_device(struct device *dev,
+ dma_addr_t addr,
+ unsigned long offset, size_t size,
+ enum dma_data_direction dir);
#endif /* _LINUX_VIRTIO_H */
--
2.32.0.3.g01195cf9f
