vfio: Rename user_iova of vfio_dma_rw()

Following the updated vfio_pin/unpin_pages(), use the simpler "iova".
Reviewed-by: NChristoph Hellwig <hch@lst.de>
Reviewed-by: NJason Gunthorpe <jgg@nvidia.com>
Reviewed-by: NKevin Tian <kevin.tian@intel.com>
Tested-by: NTerrence Xu <terrence.xu@intel.com>
Tested-by: NEric Farman <farman@linux.ibm.com>
Signed-off-by: NNicolin Chen <nicolinc@nvidia.com>
Link: https://lore.kernel.org/r/20220723020256.30081-9-nicolinc@nvidia.comSigned-off-by: NAlex Williamson <alex.williamson@redhat.com>

drivers/vfio/vfio.c

@@ -2012,13 +2012,13 @@ EXPORT_SYMBOL(vfio_unpin_pages);
  * not a real device DMA, it is not necessary to pin the user space memory.
  *
  * @device [in]		: VFIO device
- * @user_iova [in]	: base IOVA of a user space buffer
+ * @iova [in]		: base IOVA of a user space buffer
  * @data [in]		: pointer to kernel buffer
  * @len [in]		: kernel buffer length
  * @write		: indicate read or write
  * Return error code on failure or 0 on success.
  */
-int vfio_dma_rw(struct vfio_device *device, dma_addr_t user_iova, void *data,
+int vfio_dma_rw(struct vfio_device *device, dma_addr_t iova, void *data,
 		size_t len, bool write)
 {
 	struct vfio_container *container;
@@ -2034,7 +2034,7 @@ int vfio_dma_rw(struct vfio_device *device, dma_addr_t user_iova, void *data,
 
 	if (likely(driver && driver->ops->dma_rw))
 		ret = driver->ops->dma_rw(container->iommu_data,
-					  user_iova, data, len, write);
+					  iova, data, len, write);
 	else
 		ret = -ENOTTY;
 	return ret;

include/linux/vfio.h

@@ -164,7 +164,7 @@ bool vfio_file_has_dev(struct file *file, struct vfio_device *device);
 int vfio_pin_pages(struct vfio_device *device, dma_addr_t iova,
 		   int npage, int prot, unsigned long *phys_pfn);
 void vfio_unpin_pages(struct vfio_device *device, dma_addr_t iova, int npage);
-int vfio_dma_rw(struct vfio_device *device, dma_addr_t user_iova,
+int vfio_dma_rw(struct vfio_device *device, dma_addr_t iova,
 		void *data, size_t len, bool write);
 
 /*