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
21struct gntdev_dmabuf_priv;
22
23struct 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
39struct 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
46struct 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
86struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count,
87					  int dma_flags);
88
89void gntdev_add_map(struct gntdev_priv *priv, struct gntdev_grant_map *add);
90
91void gntdev_put_map(struct gntdev_priv *priv, struct gntdev_grant_map *map);
92
93bool gntdev_test_page_count(unsigned int count);
94
95int gntdev_map_grant_pages(struct gntdev_grant_map *map);
96
97#endif
98