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 #include <xen/grant_table.h>
  20
  21 struct gntdev_dmabuf_priv;
  22
  23 struct gntdev_priv {
  24         /* Maps with visible offsets in the file descriptor. */
  25         struct list_head maps;
  26         /* lock protects maps and freeable_maps. */
  27         struct mutex lock;
  28
  29 #ifdef CONFIG_XEN_GRANT_DMA_ALLOC
  30         /* Device for which DMA memory is allocated. */
  31         struct device *dma_dev;
  32 #endif
  33
  34 #ifdef CONFIG_XEN_GNTDEV_DMABUF
  35         struct gntdev_dmabuf_priv *dmabuf_priv;
  36 #endif
  37 };
  38
  39 struct gntdev_unmap_notify {
  40         int flags;
  41         /* Address relative to the start of the gntdev_grant_map. */
  42         int addr;
  43         evtchn_port_t event;
  44 };
  45
  46 struct gntdev_grant_map {
  47         atomic_t in_use;
  48         struct mmu_interval_notifier notifier;
  49         bool notifier_init;
  50         struct list_head next;
  51         int index;
  52         int count;
  53         int flags;
  54         refcount_t users;
  55         struct gntdev_unmap_notify notify;
  56         struct ioctl_gntdev_grant_ref *grants;
  57         struct gnttab_map_grant_ref   *map_ops;
  58         struct gnttab_unmap_grant_ref *unmap_ops;
  59         struct gnttab_map_grant_ref   *kmap_ops;
  60         struct gnttab_unmap_grant_ref *kunmap_ops;
  61         bool *being_removed;
  62         struct page **pages;
  63         unsigned long pages_vm_start;
  64
  65 #ifdef CONFIG_XEN_GRANT_DMA_ALLOC
  66         /*
  67          * If dmabuf_vaddr is not NULL then this mapping is backed by DMA
  68          * capable memory.
  69          */
  70
  71         struct device *dma_dev;
  72         /* Flags used to create this DMA buffer: GNTDEV_DMA_FLAG_XXX. */
  73         int dma_flags;
  74         void *dma_vaddr;
  75         dma_addr_t dma_bus_addr;
  76         /* Needed to avoid allocation in gnttab_dma_free_pages(). */
  77         xen_pfn_t *frames;
  78 #endif
  79
  80         /* Number of live grants */
  81         atomic_t live_grants;
  82         /* Needed to avoid allocation in __unmap_grant_pages */
  83         struct gntab_unmap_queue_data unmap_data;
  84 };
  85
  86 struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count,
  87                                           int dma_flags);
  88
  89 void gntdev_add_map(struct gntdev_priv *priv, struct gntdev_grant_map *add);
  90
  91 void gntdev_put_map(struct gntdev_priv *priv, struct gntdev_grant_map *map);
  92
  93 bool gntdev_test_page_count(unsigned int count);
  94
  95 int gntdev_map_grant_pages(struct gntdev_grant_map *map);
  96
  97 #endif