1/* SPDX-License-Identifier: GPL-2.0 */
2/*
3 * PCI Peer 2 Peer DMA support.
4 *
5 * Copyright (c) 2016-2018, Logan Gunthorpe
6 * Copyright (c) 2016-2017, Microsemi Corporation
7 * Copyright (c) 2017, Christoph Hellwig
8 * Copyright (c) 2018, Eideticom Inc.
9 */
10
11#ifndef _LINUX_PCI_P2PDMA_H
12#define _LINUX_PCI_P2PDMA_H
13
14#include <linux/pci.h>
15
16struct block_device;
17struct scatterlist;
18
19#ifdef CONFIG_PCI_P2PDMA
20int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
21 u64 offset);
22int pci_p2pdma_distance_many(struct pci_dev *provider, struct device **clients,
23 int num_clients, bool verbose);
24bool pci_has_p2pmem(struct pci_dev *pdev);
25struct pci_dev *pci_p2pmem_find_many(struct device **clients, int num_clients);
26void *pci_alloc_p2pmem(struct pci_dev *pdev, size_t size);
27void pci_free_p2pmem(struct pci_dev *pdev, void *addr, size_t size);
28pci_bus_addr_t pci_p2pmem_virt_to_bus(struct pci_dev *pdev, void *addr);
29struct scatterlist *pci_p2pmem_alloc_sgl(struct pci_dev *pdev,
30 unsigned int *nents, u32 length);
31void pci_p2pmem_free_sgl(struct pci_dev *pdev, struct scatterlist *sgl);
32void pci_p2pmem_publish(struct pci_dev *pdev, bool publish);
33int pci_p2pdma_enable_store(const char *page, struct pci_dev **p2p_dev,
34 bool *use_p2pdma);
35ssize_t pci_p2pdma_enable_show(char *page, struct pci_dev *p2p_dev,
36 bool use_p2pdma);
37#else /* CONFIG_PCI_P2PDMA */
38static inline int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar,
39 size_t size, u64 offset)
40{
41 return -EOPNOTSUPP;
42}
43static inline int pci_p2pdma_distance_many(struct pci_dev *provider,
44 struct device **clients, int num_clients, bool verbose)
45{
46 return -1;
47}
48static inline bool pci_has_p2pmem(struct pci_dev *pdev)
49{
50 return false;
51}
52static inline struct pci_dev *pci_p2pmem_find_many(struct device **clients,
53 int num_clients)
54{
55 return NULL;
56}
57static inline void *pci_alloc_p2pmem(struct pci_dev *pdev, size_t size)
58{
59 return NULL;
60}
61static inline void pci_free_p2pmem(struct pci_dev *pdev, void *addr,
62 size_t size)
63{
64}
65static inline pci_bus_addr_t pci_p2pmem_virt_to_bus(struct pci_dev *pdev,
66 void *addr)
67{
68 return 0;
69}
70static inline struct scatterlist *pci_p2pmem_alloc_sgl(struct pci_dev *pdev,
71 unsigned int *nents, u32 length)
72{
73 return NULL;
74}
75static inline void pci_p2pmem_free_sgl(struct pci_dev *pdev,
76 struct scatterlist *sgl)
77{
78}
79static inline void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
80{
81}
82static inline int pci_p2pdma_enable_store(const char *page,
83 struct pci_dev **p2p_dev, bool *use_p2pdma)
84{
85 *use_p2pdma = false;
86 return 0;
87}
88static inline ssize_t pci_p2pdma_enable_show(char *page,
89 struct pci_dev *p2p_dev, bool use_p2pdma)
90{
91 return sprintf(page, "none\n");
92}
93#endif /* CONFIG_PCI_P2PDMA */
94
95
96static inline int pci_p2pdma_distance(struct pci_dev *provider,
97 struct device *client, bool verbose)
98{
99 return pci_p2pdma_distance_many(provider, clients: &client, num_clients: 1, verbose);
100}
101
102static inline struct pci_dev *pci_p2pmem_find(struct device *client)
103{
104 return pci_p2pmem_find_many(clients: &client, num_clients: 1);
105}
106
107#endif /* _LINUX_PCI_P2P_H */
108

source code of linux/include/linux/pci-p2pdma.h