1 /* SPDX-License-Identifier: GPL-2.0 WITH Linux-syscall-note */
2 /*
3  * drivers/staging/android/uapi/ion.h
4  *
5  * Copyright (C) 2011 Google, Inc.
6  */
7 
8 #ifndef _LINUX_ION_H
9 #define _LINUX_ION_H
10 
11 #include <linux/ioctl.h>
12 #include <linux/types.h>
13 
14 /**
15  * ion_heap_types - list of all possible types of heaps that Android can use
16  *
17  * @ION_HEAP_TYPE_SYSTEM:        Reserved heap id for ion heap that allocates
18  *				 memory using alloc_page(). Also, supports
19  *				 deferred free and allocation pools.
20 * @ION_HEAP_TYPE_DMA:		 Reserved heap id for ion heap that manages
21  * 				 single CMA (contiguous memory allocator)
22  * 				 region. Uses standard DMA APIs for
23  *				 managing memory within the CMA region.
24  */
25 enum ion_heap_type {
26 	ION_HEAP_TYPE_SYSTEM = 0,
27 	ION_HEAP_TYPE_DMA = 2,
28 	/* reserved range for future standard heap types */
29 	ION_HEAP_TYPE_CUSTOM = 16,
30 	ION_HEAP_TYPE_MAX = 31,
31 };
32 
33 /**
34  * ion_heap_id - list of standard heap ids that Android can use
35  *
36  * @ION_HEAP_SYSTEM		Id for the ION_HEAP_TYPE_SYSTEM
37  * @ION_HEAP_DMA_START 		Start of reserved id range for heaps of type
38  *				ION_HEAP_TYPE_DMA
39  * @ION_HEAP_DMA_END		End of reserved id range for heaps of type
40  *				ION_HEAP_TYPE_DMA
41  * @ION_HEAP_CUSTOM_START	Start of reserved id range for heaps of custom
42  *				type
43  * @ION_HEAP_CUSTOM_END		End of reserved id range for heaps of custom
44  *				type
45  */
46 enum ion_heap_id {
47 	ION_HEAP_SYSTEM = (1 << ION_HEAP_TYPE_SYSTEM),
48 	ION_HEAP_DMA_START = (ION_HEAP_SYSTEM << 1),
49 	ION_HEAP_DMA_END = (ION_HEAP_DMA_START << 7),
50 	ION_HEAP_CUSTOM_START = (ION_HEAP_DMA_END << 1),
51 	ION_HEAP_CUSTOM_END = (ION_HEAP_CUSTOM_START << 22),
52 };
53 
54 #define ION_NUM_MAX_HEAPS	(32)
55 
56 /**
57  * allocation flags - the lower 16 bits are used by core ion, the upper 16
58  * bits are reserved for use by the heaps themselves.
59  */
60 
61 /*
62  * mappings of this buffer should be cached, ion will do cache maintenance
63  * when the buffer is mapped for dma
64  */
65 #define ION_FLAG_CACHED		1
66 
67 /**
68  * DOC: Ion Userspace API
69  *
70  * create a client by opening /dev/ion
71  * most operations handled via following ioctls
72  *
73  */
74 
75 /**
76  * struct ion_allocation_data - metadata passed from userspace for allocations
77  * @len:		size of the allocation
78  * @heap_id_mask:	mask of heap ids to allocate from
79  * @flags:		flags passed to heap
80  * @handle:		pointer that will be populated with a cookie to use to
81  *			refer to this allocation
82  *
83  * Provided by userspace as an argument to the ioctl
84  */
85 struct ion_allocation_data {
86 	__u64 len;
87 	__u32 heap_id_mask;
88 	__u32 flags;
89 	__u32 fd;
90 	__u32 unused;
91 };
92 
93 #define MAX_HEAP_NAME			32
94 
95 /**
96  * struct ion_heap_data - data about a heap
97  * @name - first 32 characters of the heap name
98  * @type - heap type
99  * @heap_id - heap id for the heap
100  */
101 struct ion_heap_data {
102 	char name[MAX_HEAP_NAME];
103 	__u32 type;
104 	__u32 heap_id;
105 	__u32 reserved0;
106 	__u32 reserved1;
107 	__u32 reserved2;
108 };
109 
110 /**
111  * struct ion_heap_query - collection of data about all heaps
112  * @cnt - total number of heaps to be copied
113  * @heaps - buffer to copy heap data
114  */
115 struct ion_heap_query {
116 	__u32 cnt; /* Total number of heaps to be copied */
117 	__u32 reserved0; /* align to 64bits */
118 	__u64 heaps; /* buffer to be populated */
119 	__u32 reserved1;
120 	__u32 reserved2;
121 };
122 
123 #define ION_IOC_MAGIC		'I'
124 
125 /**
126  * DOC: ION_IOC_ALLOC - allocate memory
127  *
128  * Takes an ion_allocation_data struct and returns it with the handle field
129  * populated with the opaque handle for the allocation.
130  */
131 #define ION_IOC_ALLOC		_IOWR(ION_IOC_MAGIC, 0, \
132 				      struct ion_allocation_data)
133 
134 /**
135  * DOC: ION_IOC_HEAP_QUERY - information about available heaps
136  *
137  * Takes an ion_heap_query structure and populates information about
138  * available Ion heaps.
139  */
140 #define ION_IOC_HEAP_QUERY     _IOWR(ION_IOC_MAGIC, 8, \
141 					struct ion_heap_query)
142 
143 /**
144  * DOC: ION_IOC_HEAP_ABI_VERSION - return ABI version
145  *
146  * Returns ABI version for this driver
147  */
148 #define ION_IOC_ABI_VERSION    _IOR(ION_IOC_MAGIC, 9, \
149 					__u32)
150 #endif /* _LINUX_ION_H */
151