xref: /openbmc/linux/drivers/xen/gntdev-common.h (revision 005f3e67)
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 	/* lock protects maps and freeable_maps. */
25 	struct mutex lock;
26 
27 #ifdef CONFIG_XEN_GRANT_DMA_ALLOC
28 	/* Device for which DMA memory is allocated. */
29 	struct device *dma_dev;
30 #endif
31 
32 #ifdef CONFIG_XEN_GNTDEV_DMABUF
33 	struct gntdev_dmabuf_priv *dmabuf_priv;
34 #endif
35 };
36 
37 struct gntdev_unmap_notify {
38 	int flags;
39 	/* Address relative to the start of the gntdev_grant_map. */
40 	int addr;
41 	int event;
42 };
43 
44 struct gntdev_grant_map {
45 	struct mmu_interval_notifier notifier;
46 	struct list_head next;
47 	struct vm_area_struct *vma;
48 	int index;
49 	int count;
50 	int flags;
51 	refcount_t users;
52 	struct gntdev_unmap_notify notify;
53 	struct ioctl_gntdev_grant_ref *grants;
54 	struct gnttab_map_grant_ref   *map_ops;
55 	struct gnttab_unmap_grant_ref *unmap_ops;
56 	struct gnttab_map_grant_ref   *kmap_ops;
57 	struct gnttab_unmap_grant_ref *kunmap_ops;
58 	struct page **pages;
59 	unsigned long pages_vm_start;
60 
61 #ifdef CONFIG_XEN_GRANT_DMA_ALLOC
62 	/*
63 	 * If dmabuf_vaddr is not NULL then this mapping is backed by DMA
64 	 * capable memory.
65 	 */
66 
67 	struct device *dma_dev;
68 	/* Flags used to create this DMA buffer: GNTDEV_DMA_FLAG_XXX. */
69 	int dma_flags;
70 	void *dma_vaddr;
71 	dma_addr_t dma_bus_addr;
72 	/* Needed to avoid allocation in gnttab_dma_free_pages(). */
73 	xen_pfn_t *frames;
74 #endif
75 };
76 
77 struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count,
78 					  int dma_flags);
79 
80 void gntdev_add_map(struct gntdev_priv *priv, struct gntdev_grant_map *add);
81 
82 void gntdev_put_map(struct gntdev_priv *priv, struct gntdev_grant_map *map);
83 
84 bool gntdev_test_page_count(unsigned int count);
85 
86 int gntdev_map_grant_pages(struct gntdev_grant_map *map);
87 
88 #endif
89