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1/* SPDX-License-Identifier: GPL-2.0 */2/*3 * PCI Peer 2 Peer DMA support.4 *5 * Copyright (c) 2016-2018, Logan Gunthorpe6 * Copyright (c) 2016-2017, Microsemi Corporation7 * Copyright (c) 2017, Christoph Hellwig8 * Copyright (c) 2018, Eideticom Inc.9 */10 11#ifndef _LINUX_PCI_P2PDMA_H12#define _LINUX_PCI_P2PDMA_H13 14#include <linux/pci.h>15 16struct block_device;17struct scatterlist;18 19#ifdef CONFIG_PCI_P2PDMA20int 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