LXR linux/include/linux/pci-p2pdma.h

   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_map_sg_attrs(struct device *dev, struct scatterlist *sg,
  34                int nents, enum dma_data_direction dir, unsigned long attrs);
  35void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
  36                int nents, enum dma_data_direction dir, unsigned long attrs);
  37int pci_p2pdma_enable_store(const char *page, struct pci_dev **p2p_dev,
  38                            bool *use_p2pdma);
  39ssize_t pci_p2pdma_enable_show(char *page, struct pci_dev *p2p_dev,
  40                               bool use_p2pdma);
  41#else /* CONFIG_PCI_P2PDMA */
  42static inline int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar,
  43                size_t size, u64 offset)
  44{
  45        return -EOPNOTSUPP;
  46}
  47static inline int pci_p2pdma_distance_many(struct pci_dev *provider,
  48        struct device **clients, int num_clients, bool verbose)
  49{
  50        return -1;
  51}
  52static inline bool pci_has_p2pmem(struct pci_dev *pdev)
  53{
  54        return false;
  55}
  56static inline struct pci_dev *pci_p2pmem_find_many(struct device **clients,
  57                                                   int num_clients)
  58{
  59        return NULL;
  60}
  61static inline void *pci_alloc_p2pmem(struct pci_dev *pdev, size_t size)
  62{
  63        return NULL;
  64}
  65static inline void pci_free_p2pmem(struct pci_dev *pdev, void *addr,
  66                size_t size)
  67{
  68}
  69static inline pci_bus_addr_t pci_p2pmem_virt_to_bus(struct pci_dev *pdev,
  70                                                    void *addr)
  71{
  72        return 0;
  73}
  74static inline struct scatterlist *pci_p2pmem_alloc_sgl(struct pci_dev *pdev,
  75                unsigned int *nents, u32 length)
  76{
  77        return NULL;
  78}
  79static inline void pci_p2pmem_free_sgl(struct pci_dev *pdev,
  80                struct scatterlist *sgl)
  81{
  82}
  83static inline void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
  84{
  85}
  86static inline int pci_p2pdma_map_sg_attrs(struct device *dev,
  87                struct scatterlist *sg, int nents, enum dma_data_direction dir,
  88                unsigned long attrs)
  89{
  90        return 0;
  91}
  92static inline void pci_p2pdma_unmap_sg_attrs(struct device *dev,
  93                struct scatterlist *sg, int nents, enum dma_data_direction dir,
  94                unsigned long attrs)
  95{
  96}
  97static inline int pci_p2pdma_enable_store(const char *page,
  98                struct pci_dev **p2p_dev, bool *use_p2pdma)
  99{
 100        *use_p2pdma = false;
 101        return 0;
 102}
 103static inline ssize_t pci_p2pdma_enable_show(char *page,
 104                struct pci_dev *p2p_dev, bool use_p2pdma)
 105{
 106        return sprintf(page, "none\n");
 107}
 108#endif /* CONFIG_PCI_P2PDMA */
 109
 110
 111static inline int pci_p2pdma_distance(struct pci_dev *provider,
 112        struct device *client, bool verbose)
 113{
 114        return pci_p2pdma_distance_many(provider, &client, 1, verbose);
 115}
 116
 117static inline struct pci_dev *pci_p2pmem_find(struct device *client)
 118{
 119        return pci_p2pmem_find_many(&client, 1);
 120}
 121
 122static inline int pci_p2pdma_map_sg(struct device *dev, struct scatterlist *sg,
 123                                    int nents, enum dma_data_direction dir)
 124{
 125        return pci_p2pdma_map_sg_attrs(dev, sg, nents, dir, 0);
 126}
 127
 128static inline void pci_p2pdma_unmap_sg(struct device *dev,
 129                struct scatterlist *sg, int nents, enum dma_data_direction dir)
 130{
 131        pci_p2pdma_unmap_sg_attrs(dev, sg, nents, dir, 0);
 132}
 133
 134#endif /* _LINUX_PCI_P2P_H */
 135