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 #include <xen/interface/event_channel.h>
  19
  20 struct gntdev_dmabuf_priv;
  21
  22 struct gntdev_priv {
  23         /* Maps with visible offsets in the file descriptor. */
  24         struct list_head maps;
  25         /* lock protects maps and freeable_maps. */
  26         struct mutex lock;
  27
  28 #ifdef CONFIG_XEN_GRANT_DMA_ALLOC
  29         /* Device for which DMA memory is allocated. */
  30         struct device *dma_dev;
  31 #endif
  32
  33 #ifdef CONFIG_XEN_GNTDEV_DMABUF
  34         struct gntdev_dmabuf_priv *dmabuf_priv;
  35 #endif
  36 };
  37
  38 struct gntdev_unmap_notify {
  39         int flags;
  40         /* Address relative to the start of the gntdev_grant_map. */
  41         int addr;
  42         evtchn_port_t event;
  43 };
  44
  45 struct gntdev_grant_map {
  46         struct mmu_interval_notifier notifier;
  47         struct list_head next;
  48         struct vm_area_struct *vma;
  49         int index;
  50         int count;
  51         int flags;
  52         refcount_t users;
  53         struct gntdev_unmap_notify notify;
  54         struct ioctl_gntdev_grant_ref *grants;
  55         struct gnttab_map_grant_ref   *map_ops;
  56         struct gnttab_unmap_grant_ref *unmap_ops;
  57         struct gnttab_map_grant_ref   *kmap_ops;
  58         struct gnttab_unmap_grant_ref *kunmap_ops;
  59         struct page **pages;
  60         unsigned long pages_vm_start;
  61
  62 #ifdef CONFIG_XEN_GRANT_DMA_ALLOC
  63         /*
  64          * If dmabuf_vaddr is not NULL then this mapping is backed by DMA
  65          * capable memory.
  66          */
  67
  68         struct device *dma_dev;
  69         /* Flags used to create this DMA buffer: GNTDEV_DMA_FLAG_XXX. */
  70         int dma_flags;
  71         void *dma_vaddr;
  72         dma_addr_t dma_bus_addr;
  73         /* Needed to avoid allocation in gnttab_dma_free_pages(). */
  74         xen_pfn_t *frames;
  75 #endif
  76 };
  77
  78 struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count,
  79                                           int dma_flags);
  80
  81 void gntdev_add_map(struct gntdev_priv *priv, struct gntdev_grant_map *add);
  82
  83 void gntdev_put_map(struct gntdev_priv *priv, struct gntdev_grant_map *map);
  84
  85 bool gntdev_test_page_count(unsigned int count);
  86
  87 int gntdev_map_grant_pages(struct gntdev_grant_map *map);
  88
  89 #endif