xref: /linux/drivers/xen/gntdev-common.h (revision 7d767a9528f6d203bca5e83faf1b8f2f6af3fc07)
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 	/* Free instances of struct gntdev_copy_batch. */
30 	struct gntdev_copy_batch *batch;
31 	struct mutex batch_lock;
32 
33 #ifdef CONFIG_XEN_GRANT_DMA_ALLOC
34 	/* Device for which DMA memory is allocated. */
35 	struct device *dma_dev;
36 #endif
37 
38 #ifdef CONFIG_XEN_GNTDEV_DMABUF
39 	struct gntdev_dmabuf_priv *dmabuf_priv;
40 #endif
41 };
42 
43 struct gntdev_unmap_notify {
44 	int flags;
45 	/* Address relative to the start of the gntdev_grant_map. */
46 	int addr;
47 	evtchn_port_t event;
48 };
49 
50 struct gntdev_grant_map {
51 	atomic_t in_use;
52 	struct mmu_interval_notifier notifier;
53 	bool notifier_init;
54 	struct list_head next;
55 	int index;
56 	int count;
57 	int flags;
58 	refcount_t users;
59 	struct gntdev_unmap_notify notify;
60 	struct ioctl_gntdev_grant_ref *grants;
61 	struct gnttab_map_grant_ref   *map_ops;
62 	struct gnttab_unmap_grant_ref *unmap_ops;
63 	struct gnttab_map_grant_ref   *kmap_ops;
64 	struct gnttab_unmap_grant_ref *kunmap_ops;
65 	bool *being_removed;
66 	struct page **pages;
67 	unsigned long pages_vm_start;
68 
69 #ifdef CONFIG_XEN_GRANT_DMA_ALLOC
70 	/*
71 	 * If dmabuf_vaddr is not NULL then this mapping is backed by DMA
72 	 * capable memory.
73 	 */
74 
75 	struct device *dma_dev;
76 	/* Flags used to create this DMA buffer: GNTDEV_DMA_FLAG_XXX. */
77 	int dma_flags;
78 	void *dma_vaddr;
79 	dma_addr_t dma_bus_addr;
80 	/* Needed to avoid allocation in gnttab_dma_free_pages(). */
81 	xen_pfn_t *frames;
82 #endif
83 
84 	/* Number of live grants */
85 	atomic_t live_grants;
86 	/* Needed to avoid allocation in __unmap_grant_pages */
87 	struct gntab_unmap_queue_data unmap_data;
88 };
89 
90 struct gntdev_grant_map *gntdev_alloc_map(struct gntdev_priv *priv, int count,
91 					  int dma_flags);
92 
93 void gntdev_add_map(struct gntdev_priv *priv, struct gntdev_grant_map *add);
94 
95 void gntdev_put_map(struct gntdev_priv *priv, struct gntdev_grant_map *map);
96 
97 bool gntdev_test_page_count(unsigned int count);
98 
99 int gntdev_map_grant_pages(struct gntdev_grant_map *map);
100 
101 #endif
102