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, &client, 1, verbose); 100} 101 102static 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