Merge tag 'spi-fix-v6.6-merge-window' of git://git.kernel.org/pub/scm/linux/kernel...

[platform/kernel/linux-rpi.git] / drivers / virtio / virtio_ring.c

diff --git a/drivers/virtio/virtio_ring.c b/drivers/virtio/virtio_ring.c
index 916479c..51d8f32 100644 (file)
--- a/drivers/virtio/virtio_ring.c
+++ b/drivers/virtio/virtio_ring.c
@@ -1499,7 +1499,7 @@ static inline int virtqueue_add_packed(struct virtqueue *_vq,
                }
        }
 
-       if (i < head)
+       if (i <= head)
                vq->packed.avail_wrap_counter ^= 1;
 
        /* We're using some buffers from the free list. */
@@ -3175,4 +3175,80 @@ int virtqueue_dma_mapping_error(struct virtqueue *_vq, dma_addr_t addr)
 }
 EXPORT_SYMBOL_GPL(virtqueue_dma_mapping_error);
 
+/**
+ * virtqueue_dma_need_sync - check a dma address needs sync
+ * @_vq: the struct virtqueue we're talking about.
+ * @addr: DMA address
+ *
+ * Check if the dma address mapped by the virtqueue_dma_map_* APIs needs to be
+ * synchronized
+ *
+ * return bool
+ */
+bool virtqueue_dma_need_sync(struct virtqueue *_vq, dma_addr_t addr)
+{
+       struct vring_virtqueue *vq = to_vvq(_vq);
+
+       if (!vq->use_dma_api)
+               return false;
+
+       return dma_need_sync(vring_dma_dev(vq), addr);
+}
+EXPORT_SYMBOL_GPL(virtqueue_dma_need_sync);
+
+/**
+ * virtqueue_dma_sync_single_range_for_cpu - dma sync for cpu
+ * @_vq: the struct virtqueue we're talking about.
+ * @addr: DMA address
+ * @offset: DMA address offset
+ * @size: buf size for sync
+ * @dir: DMA direction
+ *
+ * Before calling this function, use virtqueue_dma_need_sync() to confirm that
+ * the DMA address really needs to be synchronized
+ *
+ */
+void virtqueue_dma_sync_single_range_for_cpu(struct virtqueue *_vq,
+                                            dma_addr_t addr,
+                                            unsigned long offset, size_t size,
+                                            enum dma_data_direction dir)
+{
+       struct vring_virtqueue *vq = to_vvq(_vq);
+       struct device *dev = vring_dma_dev(vq);
+
+       if (!vq->use_dma_api)
+               return;
+
+       dma_sync_single_range_for_cpu(dev, addr, offset, size,
+                                     DMA_BIDIRECTIONAL);
+}
+EXPORT_SYMBOL_GPL(virtqueue_dma_sync_single_range_for_cpu);
+
+/**
+ * virtqueue_dma_sync_single_range_for_device - dma sync for device
+ * @_vq: the struct virtqueue we're talking about.
+ * @addr: DMA address
+ * @offset: DMA address offset
+ * @size: buf size for sync
+ * @dir: DMA direction
+ *
+ * Before calling this function, use virtqueue_dma_need_sync() to confirm that
+ * the DMA address really needs to be synchronized
+ */
+void virtqueue_dma_sync_single_range_for_device(struct virtqueue *_vq,
+                                               dma_addr_t addr,
+                                               unsigned long offset, size_t size,
+                                               enum dma_data_direction dir)
+{
+       struct vring_virtqueue *vq = to_vvq(_vq);
+       struct device *dev = vring_dma_dev(vq);
+
+       if (!vq->use_dma_api)
+               return;
+
+       dma_sync_single_range_for_device(dev, addr, offset, size,
+                                        DMA_BIDIRECTIONAL);
+}
+EXPORT_SYMBOL_GPL(virtqueue_dma_sync_single_range_for_device);
+
 MODULE_LICENSE("GPL");