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
  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_map_sg_attrs(struct device *dev, struct scatterlist *sg,
  34                 int nents, enum dma_data_direction dir, unsigned long attrs);
  35 void pci_p2pdma_unmap_sg_attrs(struct device *dev, struct scatterlist *sg,
  36                 int nents, enum dma_data_direction dir, unsigned long attrs);
  37 int pci_p2pdma_enable_store(const char *page, struct pci_dev **p2p_dev,
  38                             bool *use_p2pdma);
  39 ssize_t pci_p2pdma_enable_show(char *page, struct pci_dev *p2p_dev,
  40                                bool use_p2pdma);
  41 #else /* CONFIG_PCI_P2PDMA */
  42 static inline int pci_p2pdma_add_resource(struct pci_dev *pdev, int bar,
  43                 size_t size, u64 offset)
  44 {
  45         return -EOPNOTSUPP;
  46 }
  47 static inline int pci_p2pdma_distance_many(struct pci_dev *provider,
  48         struct device **clients, int num_clients, bool verbose)
  49 {
  50         return -1;
  51 }
  52 static inline bool pci_has_p2pmem(struct pci_dev *pdev)
  53 {
  54         return false;
  55 }
  56 static inline struct pci_dev *pci_p2pmem_find_many(struct device **clients,
  57                                                    int num_clients)
  58 {
  59         return NULL;
  60 }
  61 static inline void *pci_alloc_p2pmem(struct pci_dev *pdev, size_t size)
  62 {
  63         return NULL;
  64 }
  65 static inline void pci_free_p2pmem(struct pci_dev *pdev, void *addr,
  66                 size_t size)
  67 {
  68 }
  69 static inline pci_bus_addr_t pci_p2pmem_virt_to_bus(struct pci_dev *pdev,
  70                                                     void *addr)
  71 {
  72         return 0;
  73 }
  74 static inline struct scatterlist *pci_p2pmem_alloc_sgl(struct pci_dev *pdev,
  75                 unsigned int *nents, u32 length)
  76 {
  77         return NULL;
  78 }
  79 static inline void pci_p2pmem_free_sgl(struct pci_dev *pdev,
  80                 struct scatterlist *sgl)
  81 {
  82 }
  83 static inline void pci_p2pmem_publish(struct pci_dev *pdev, bool publish)
  84 {
  85 }
  86 static 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 }
  92 static 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 }
  97 static 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 }
 103 static 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
 111 static 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
 117 static inline struct pci_dev *pci_p2pmem_find(struct device *client)
 118 {
 119         return pci_p2pmem_find_many(&client, 1);
 120 }
 121
 122 static 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
 128 static 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 */