[RFC 3/8] dma-buf: Add support for IOV interconnect

[Vivek Kasireddy <vivek.kasireddy@intel.com>]

The IOV interconnect is a virtual interconnect between an SRIOV
physical function (PF) and its virtual functions (VFs). In order
for negotiation (or match) to succeed, the exporter is expected
to be a VF while the importer is expected to be the PF.

Cc: Jason Gunthorpe <jgg@nvidia.com>
Cc: Christian Koenig <christian.koenig@amd.com>
Cc: Sumit Semwal <sumit.semwal@linaro.org>
Cc: Thomas Hellström <thomas.hellstrom@linux.intel.com>
Cc: Simona Vetter <simona.vetter@ffwll.ch>
Signed-off-by: Vivek Kasireddy <vivek.kasireddy@intel.com>
---
 include/linux/dma-buf-interconnect.h | 16 ++++++++++++++++
 1 file changed, 16 insertions(+)

diff --git a/include/linux/dma-buf-interconnect.h b/include/linux/dma-buf-interconnect.h
index a72f65ed4806..b569dcab86ce 100644
--- a/include/linux/dma-buf-interconnect.h
+++ b/include/linux/dma-buf-interconnect.h
@@ -3,8 +3,17 @@
 #ifndef __DMA_BUF_INTERCONNECT_H__
 #define __DMA_BUF_INTERCONNECT_H__
 
+#include <linux/pci.h>
 #include <linux/xarray.h>
 
+#define CREATE_IOV_INTERCONNECT(pdev, bar) {		\
+	&(const struct dma_buf_iov_interconnect) {	\
+		.base.type = DMA_BUF_INTERCONNECT_IOV,	\
+		.pdev = (pdev),				\
+		.bar = (bar),				\
+	}.base						\
+}
+
 struct dma_buf_attachment;
 
 struct dma_buf_ranges {
@@ -14,6 +23,7 @@ struct dma_buf_ranges {
 
 enum dma_buf_interconnect_type {
 	DMA_BUF_INTERCONNECT_NONE = 0,
+	DMA_BUF_INTERCONNECT_IOV,
 };
 
 struct dma_buf_interconnect {
@@ -24,6 +34,12 @@ struct dma_buf_interconnect_match {
 	const struct dma_buf_interconnect *interconnect;
 };
 
+struct dma_buf_iov_interconnect {
+	struct dma_buf_interconnect base;
+	struct pci_dev *pdev;
+	unsigned int bar;
+};
+
 struct dma_buf_interconnect_ops {
 	int (*map_interconnect)(struct dma_buf_attachment *attach,
 				struct dma_buf_ranges *ranges);
-- 
2.50.1