xref: /linux/include/linux/pci-p2pdma.h (revision 0d06132f)
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 
16 struct block_device;
17 struct scatterlist;
18 
19 #ifdef CONFIG_PCI_P2PDMA
20 int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar, size_t size,
21 		u64 offset);
22 int pci_p2pdma_distance_many(struct pci_dev *provider, struct device **clients,
23 			     int num_clients, bool verbose);
24 bool pci_has_p2pmem(struct pci_dev *pdev);
25 struct pci_dev *pci_p2pmem_find_many(struct device **clients, int num_clients);
26 void *pci_alloc_p2pmem(struct pci_dev *pdev, size_t size);
27 void pci_free_p2pmem(struct pci_dev *pdev, void *addr, size_t size);
28 pci_bus_addr_t pci_p2pmem_virt_to_bus(struct pci_dev *pdev, void *addr);
29 struct scatterlist *pci_p2pmem_alloc_sgl(struct pci_dev *pdev,
30 					 unsigned int *nents, u32 length);
31 void pci_p2pmem_free_sgl(struct pci_dev *pdev, struct scatterlist *sgl);
32 void pci_p2pmem_publish(struct pci_dev *pdev, bool publish);
33 int pci_p2pdma_enable_store(const char *page, struct pci_dev **p2p_dev,
34 			    bool *use_p2pdma);
35 ssize_t pci_p2pdma_enable_show(char *page, struct pci_dev *p2p_dev,
36 			       bool use_p2pdma);
37 #else /* CONFIG_PCI_P2PDMA */
pci_p2pdma_add_resource(struct pci_dev * pdev,int bar,size_t size,u64 offset)38 static inline int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar,
39 		size_t size, u64 offset)
40 {
41 	return -EOPNOTSUPP;
42 }
pci_p2pdma_distance_many(struct pci_dev * provider,struct device ** clients,int num_clients,bool verbose)43 static inline int pci_p2pdma_distance_many(struct pci_dev *provider,
44 	struct device **clients, int num_clients, bool verbose)
45 {
46 	return -1;
47 }
pci_has_p2pmem(struct pci_dev * pdev)48 static inline bool pci_has_p2pmem(struct pci_dev *pdev)
49 {
50 	return false;
51 }
pci_p2pmem_find_many(struct device ** clients,int num_clients)52 static inline struct pci_dev *pci_p2pmem_find_many(struct device **clients,
53 						   int num_clients)
54 {
55 	return NULL;
56 }
pci_alloc_p2pmem(struct pci_dev * pdev,size_t size)57 static inline void *pci_alloc_p2pmem(struct pci_dev *pdev, size_t size)
58 {
59 	return NULL;
60 }
pci_free_p2pmem(struct pci_dev * pdev,void * addr,size_t size)61 static inline void pci_free_p2pmem(struct pci_dev *pdev, void *addr,
62 		size_t size)
63 {
64 }
pci_p2pmem_virt_to_bus(struct pci_dev * pdev,void * addr)65 static inline pci_bus_addr_t pci_p2pmem_virt_to_bus(struct pci_dev *pdev,
66 						    void *addr)
67 {
68 	return 0;
69 }
pci_p2pmem_alloc_sgl(struct pci_dev * pdev,unsigned int * nents,u32 length)70 static inline struct scatterlist *pci_p2pmem_alloc_sgl(struct pci_dev *pdev,
71 		unsigned int *nents, u32 length)
72 {
73 	return NULL;
74 }
pci_p2pmem_free_sgl(struct pci_dev * pdev,struct scatterlist * sgl)75 static inline void pci_p2pmem_free_sgl(struct pci_dev *pdev,
76 		struct scatterlist *sgl)
77 {
78 }
pci_p2pmem_publish(struct pci_dev * pdev,bool publish)79 static inline void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
80 {
81 }
pci_p2pdma_enable_store(const char * page,struct pci_dev ** p2p_dev,bool * use_p2pdma)82 static 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 }
pci_p2pdma_enable_show(char * page,struct pci_dev * p2p_dev,bool use_p2pdma)88 static 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 
pci_p2pdma_distance(struct pci_dev * provider,struct device * client,bool verbose)96 static inline int pci_p2pdma_distance(struct pci_dev *provider,
97 	struct device *client, bool verbose)
98 {
99 	return pci_p2pdma_distance_many(provider, &client, 1, verbose);
100 }
101 
pci_p2pmem_find(struct device * client)102 static inline struct pci_dev *pci_p2pmem_find(struct device *client)
103 {
104 	return pci_p2pmem_find_many(&client, 1);
105 }
106 
107 #endif /* _LINUX_PCI_P2P_H */
108