1 files changed, 114 insertions, 0 deletions

diff --git a/include/linux/pci-p2pdma.h b/include/linux/pci-p2pdma.h
new file mode 100644
index 000000000000..bca9bc3e5be7
--- /dev/null
+++ b/include/linux/pci-p2pdma.h
@@ -0,0 +1,114 @@
+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * PCI Peer 2 Peer DMA support.
+ *
+ * Copyright (c) 2016-2018, Logan Gunthorpe
+ * Copyright (c) 2016-2017, Microsemi Corporation
+ * Copyright (c) 2017, Christoph Hellwig
+ * Copyright (c) 2018, Eideticom Inc.
+ */
+
+#ifndef _LINUX_PCI_P2PDMA_H
+#define _LINUX_PCI_P2PDMA_H
+
+#include <linux/pci.h>
+
+struct block_device;
+struct scatterlist;
+
+#ifdef CONFIG_PCI_P2PDMA
+int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
+                u64 offset);
+int pci_p2pdma_distance_many(struct pci_dev *provider, struct device **clients,
+                             int num_clients, bool verbose);
+bool pci_has_p2pmem(struct pci_dev *pdev);
+struct pci_dev *pci_p2pmem_find_many(struct device **clients, int num_clients);
+void *pci_alloc_p2pmem(struct pci_dev *pdev, size_t size);
+void pci_free_p2pmem(struct pci_dev *pdev, void *addr, size_t size);
+pci_bus_addr_t pci_p2pmem_virt_to_bus(struct pci_dev *pdev, void *addr);
+struct scatterlist *pci_p2pmem_alloc_sgl(struct pci_dev *pdev,
+                                         unsigned int *nents, u32 length);
+void pci_p2pmem_free_sgl(struct pci_dev *pdev, struct scatterlist *sgl);
+void pci_p2pmem_publish(struct pci_dev *pdev, bool publish);
+int pci_p2pdma_map_sg(struct device *dev, struct scatterlist *sg, int nents,
+                      enum dma_data_direction dir);
+int pci_p2pdma_enable_store(const char *page, struct pci_dev **p2p_dev,
+                            bool *use_p2pdma);
+ssize_t pci_p2pdma_enable_show(char *page, struct pci_dev *p2p_dev,
+                               bool use_p2pdma);
+#else /* CONFIG_PCI_P2PDMA */
+static inline int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar,
+                size_t size, u64 offset)
+{
+        return -EOPNOTSUPP;
+}
+static inline int pci_p2pdma_distance_many(struct pci_dev *provider,
+        struct device **clients, int num_clients, bool verbose)
+{
+        return -1;
+}
+static inline bool pci_has_p2pmem(struct pci_dev *pdev)
+{
+        return false;
+}
+static inline struct pci_dev *pci_p2pmem_find_many(struct device **clients,
+                                                   int num_clients)
+{
+        return NULL;
+}
+static inline void *pci_alloc_p2pmem(struct pci_dev *pdev, size_t size)
+{
+        return NULL;
+}
+static inline void pci_free_p2pmem(struct pci_dev *pdev, void *addr,
+                size_t size)
+{
+}
+static inline pci_bus_addr_t pci_p2pmem_virt_to_bus(struct pci_dev *pdev,
+                                                    void *addr)
+{
+        return 0;
+}
+static inline struct scatterlist *pci_p2pmem_alloc_sgl(struct pci_dev *pdev,
+                unsigned int *nents, u32 length)
+{
+        return NULL;
+}
+static inline void pci_p2pmem_free_sgl(struct pci_dev *pdev,
+                struct scatterlist *sgl)
+{
+}
+static inline void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
+{
+}
+static inline int pci_p2pdma_map_sg(struct device *dev,
+                struct scatterlist *sg, int nents, enum dma_data_direction dir)
+{
+        return 0;
+}
+static inline int pci_p2pdma_enable_store(const char *page,
+                struct pci_dev **p2p_dev, bool *use_p2pdma)
+{
+        *use_p2pdma = false;
+        return 0;
+}
+static inline ssize_t pci_p2pdma_enable_show(char *page,
+                struct pci_dev *p2p_dev, bool use_p2pdma)
+{
+        return sprintf(page, "none\n");
+}
+#endif /* CONFIG_PCI_P2PDMA */
+
+
+static inline int pci_p2pdma_distance(struct pci_dev *provider,
+        struct device *client, bool verbose)
+{
+        return pci_p2pdma_distance_many(provider, &client, 1, verbose);
+}
+
+static inline struct pci_dev *pci_p2pmem_find(struct device *client)
+{
+        return pci_p2pmem_find_many(&client, 1);
+}
+
+#endif /* _LINUX_PCI_P2P_H */