drivers/xen/gntdev-common.h

   1 /* SPDX-License-Identifier: GPL-2.0 */
   2
   3 /*
   4  * Common functionality of grant device.
   5  *
   6  * Copyright (c) 2006-2007, D G Murray.
   7  *           (c) 2009 Gerd Hoffmann <kraxel@redhat.com>
   8  *           (c) 2018 Oleksandr Andrushchenko, EPAM Systems Inc.
   9  */
  10
  11 #ifndef _GNTDEV_COMMON_H
  12 #define _GNTDEV_COMMON_H
  13
  14 #include <linux/mm.h>
  15 #include <linux/mman.h>
  16 #include <linux/mmu_notifier.h>
  17 #include <linux/types.h>
  18
  19 struct gntdev_dmabuf_priv;
  20
  21 struct gntdev_priv {
  22         /* Maps with visible offsets in the file descriptor. */
  23         struct list_head maps;
  24         /*
  25          * Maps that are not visible; will be freed on munmap.
  26          * Only populated if populate_freeable_maps == 1
  27          */
  28         struct list_head freeable_maps;
  29         /* lock protects maps and freeable_maps. */
  30         struct mutex lock;
  31         struct mm_struct *mm;
  32         struct mmu_notifier mn;
  33
  34 #ifdef CONFIG_XEN_GRANT_DMA_ALLOC
  35         /* Device for which DMA memory is allocated. */
  36         struct device *dma_dev;
  37 #endif
  38
  39 #ifdef CONFIG_XEN_GNTDEV_DMABUF
  40         struct gntdev_dmabuf_priv *dmabuf_priv;
  41 #endif
  42 };
  43
  44 struct gntdev_unmap_notify {
  45         int flags;
  46         /* Address relative to the start of the gntdev_grant_map. */
  47         int addr;
  48         int event;
  49 };
  50
  51 struct gntdev_grant_map {
  52         struct list_head next;
  53         struct vm_area_struct *vma;
  54         int index;
  55         int count;
  56         int flags;
  57         refcount_t users;
  58         struct gntdev_unmap_notify notify;
  59         struct ioctl_gntdev_grant_ref *grants;
  60         struct gnttab_map_grant_ref   *map_ops;
  61         struct gnttab_unmap_grant_ref *unmap_ops;
  62         struct gnttab_map_grant_ref   *kmap_ops;
  63         struct gnttab_unmap_grant_ref *kunmap_ops;
  64         struct page **pages;
  65         unsigned long pages_vm_start;
  66
  67 #ifdef CONFIG_XEN_GRANT_DMA_ALLOC
  68         /*
  69          * If dmabuf_vaddr is not NULL then this mapping is backed by DMA
  70          * capable memory.
  71          */
  72
  73         struct device *dma_dev;
  74         /* Flags used to create this DMA buffer: GNTDEV_DMA_FLAG_XXX. */
  75         int dma_flags;
  76         void *dma_vaddr;
  77         dma_addr_t dma_bus_addr;
  78         /* Needed to avoid allocation in gnttab_dma_free_pages(). */
  79         xen_pfn_t *frames;
  80 #endif
  81 };
  82
  83 struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count,
  84                                           int dma_flags);
  85
  86 void gntdev_add_map(struct gntdev_priv *priv, struct gntdev_grant_map *add);
  87
  88 void gntdev_put_map(struct gntdev_priv *priv, struct gntdev_grant_map *map);
  89
  90 bool gntdev_account_mapped_pages(int count);
  91
  92 int gntdev_map_grant_pages(struct gntdev_grant_map *map);
  93
  94 #endif