}
}
- if (i < head)
+ if (i <= head)
vq->packed.avail_wrap_counter ^= 1;
/* We're using some buffers from the free list. */
}
EXPORT_SYMBOL_GPL(virtqueue_set_dma_premapped);
+/**
+ * virtqueue_reset - detach and recycle all unused buffers
+ * @_vq: the struct virtqueue we're talking about.
+ * @recycle: callback to recycle unused buffers
+ *
+ * Caller must ensure we don't call this with other virtqueue operations
+ * at the same time (except where noted).
+ *
+ * Returns zero or a negative error.
+ * 0: success.
+ * -EBUSY: Failed to sync with device, vq may not work properly
+ * -ENOENT: Transport or device not supported
+ * -EPERM: Operation not permitted
+ */
+int virtqueue_reset(struct virtqueue *_vq,
+ void (*recycle)(struct virtqueue *vq, void *buf))
+{
+ struct vring_virtqueue *vq = to_vvq(_vq);
+ int err;
+
+ err = virtqueue_disable_and_recycle(_vq, recycle);
+ if (err)
+ return err;
+
+ if (vq->packed_ring)
+ virtqueue_reinit_packed(vq);
+ else
+ virtqueue_reinit_split(vq);
+
+ return virtqueue_enable_after_reset(_vq);
+}
+EXPORT_SYMBOL_GPL(virtqueue_reset);
+
/* Only available for split ring */
struct virtqueue *vring_new_virtqueue(unsigned int index,
unsigned int num,
}
EXPORT_SYMBOL_GPL(virtqueue_get_vring);
+/**
+ * virtqueue_dma_map_single_attrs - map DMA for _vq
+ * @_vq: the struct virtqueue we're talking about.
+ * @ptr: the pointer of the buffer to do dma
+ * @size: the size of the buffer to do dma
+ * @dir: DMA direction
+ * @attrs: DMA Attrs
+ *
+ * The caller calls this to do dma mapping in advance. The DMA address can be
+ * passed to this _vq when it is in pre-mapped mode.
+ *
+ * return DMA address. Caller should check that by virtqueue_dma_mapping_error().
+ */
+dma_addr_t virtqueue_dma_map_single_attrs(struct virtqueue *_vq, void *ptr,
+ size_t size,
+ enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ struct vring_virtqueue *vq = to_vvq(_vq);
+
+ if (!vq->use_dma_api)
+ return (dma_addr_t)virt_to_phys(ptr);
+
+ return dma_map_single_attrs(vring_dma_dev(vq), ptr, size, dir, attrs);
+}
+EXPORT_SYMBOL_GPL(virtqueue_dma_map_single_attrs);
+
+/**
+ * virtqueue_dma_unmap_single_attrs - unmap DMA for _vq
+ * @_vq: the struct virtqueue we're talking about.
+ * @addr: the dma address to unmap
+ * @size: the size of the buffer
+ * @dir: DMA direction
+ * @attrs: DMA Attrs
+ *
+ * Unmap the address that is mapped by the virtqueue_dma_map_* APIs.
+ *
+ */
+void virtqueue_dma_unmap_single_attrs(struct virtqueue *_vq, dma_addr_t addr,
+ size_t size, enum dma_data_direction dir,
+ unsigned long attrs)
+{
+ struct vring_virtqueue *vq = to_vvq(_vq);
+
+ if (!vq->use_dma_api)
+ return;
+
+ dma_unmap_single_attrs(vring_dma_dev(vq), addr, size, dir, attrs);
+}
+EXPORT_SYMBOL_GPL(virtqueue_dma_unmap_single_attrs);
+
+/**
+ * virtqueue_dma_mapping_error - check dma address
+ * @_vq: the struct virtqueue we're talking about.
+ * @addr: DMA address
+ *
+ * Returns 0 means dma valid. Other means invalid dma address.
+ */
+int virtqueue_dma_mapping_error(struct virtqueue *_vq, dma_addr_t addr)
+{
+ struct vring_virtqueue *vq = to_vvq(_vq);
+
+ if (!vq->use_dma_api)
+ return 0;
+
+ return dma_mapping_error(vring_dma_dev(vq), 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");
projects / platform / kernel / linux-rpi.git / blobdiff