2 * drivers/staging/android/uapi/ion.h
4 * Copyright (C) 2011 Google, Inc.
6 * This software is licensed under the terms of the GNU General Public
7 * License version 2, as published by the Free Software Foundation, and
8 * may be copied, distributed, and modified under those terms.
10 * This program is distributed in the hope that it will be useful,
11 * but WITHOUT ANY WARRANTY; without even the implied warranty of
12 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
13 * GNU General Public License for more details.
17 #ifndef _UAPI_LINUX_ION_H
18 #define _UAPI_LINUX_ION_H
20 #include <linux/ioctl.h>
21 #include <linux/types.h>
23 typedef int ion_user_handle_t;
26 * enum ion_heap_types - list of all possible types of heaps
27 * @ION_HEAP_TYPE_SYSTEM: memory allocated via vmalloc
28 * @ION_HEAP_TYPE_SYSTEM_CONTIG: memory allocated via kmalloc
29 * @ION_HEAP_TYPE_CARVEOUT: memory allocated from a prereserved
30 * carveout heap, allocations are physically
32 * @ION_HEAP_TYPE_DMA: memory allocated via DMA API
33 * @ION_NUM_HEAPS: helper for iterating over heaps, a bit mask
34 * is used to identify the heaps, so only 32
35 * total heap types are supported
39 ION_HEAP_TYPE_SYSTEM_CONTIG,
40 ION_HEAP_TYPE_CARVEOUT,
44 ION_HEAP_TYPE_CUSTOM, /* must be last so device specific heaps always
45 are at the end of this enum */
49 #define ION_HEAP_SYSTEM_MASK (1 << ION_HEAP_TYPE_SYSTEM)
50 #define ION_HEAP_SYSTEM_CONTIG_MASK (1 << ION_HEAP_TYPE_SYSTEM_CONTIG)
51 #define ION_HEAP_CARVEOUT_MASK (1 << ION_HEAP_TYPE_CARVEOUT)
52 #define ION_HEAP_TYPE_DMA_MASK (1 << ION_HEAP_TYPE_DMA)
53 #define ION_HEAP_TYPE_DRM_MASK (1 << ION_HEAP_TYPE_DRM)
55 #define ION_NUM_HEAP_IDS sizeof(unsigned int) * 8
58 * allocation flags - the lower 16 bits are used by core ion, the upper 16
59 * bits are reserved for use by the heaps themselves.
61 #define ION_FLAG_CACHED 1 /* mappings of this buffer should be
62 cached, ion will do cache
63 maintenance when the buffer is
65 #define ION_FLAG_CACHED_NEEDS_SYNC 2 /* mappings of this buffer will created
66 at mmap time, if this is set
67 caches must be managed manually */
70 * DOC: Ion Userspace API
72 * create a client by opening /dev/ion
73 * most operations handled via following ioctls
78 * struct ion_allocation_data - metadata passed from userspace for allocations
79 * @len: size of the allocation
80 * @align: required alignment of the allocation
81 * @heap_id_mask: mask of heap ids to allocate from
82 * @flags: flags passed to heap
83 * @handle: pointer that will be populated with a cookie to use to
84 * refer to this allocation
86 * Provided by userspace as an argument to the ioctl
88 struct ion_allocation_data {
91 unsigned int heap_id_mask;
93 ion_user_handle_t handle;
97 * struct ion_fd_data - metadata passed to/from userspace for a handle/fd pair
99 * @fd: a file descriptor representing that handle
101 * For ION_IOC_SHARE or ION_IOC_MAP userspace populates the handle field with
102 * the handle returned from ion alloc, and the kernel returns the file
103 * descriptor to share or map in the fd field. For ION_IOC_IMPORT, userspace
104 * provides the file descriptor and the kernel returns the handle.
107 ion_user_handle_t handle;
112 * struct ion_handle_data - a handle passed to/from the kernel
115 struct ion_handle_data {
116 ion_user_handle_t handle;
120 * struct ion_custom_data - metadata passed to/from userspace for a custom ioctl
121 * @cmd: the custom ioctl function to call
122 * @arg: additional data to pass to the custom ioctl, typically a user
123 * pointer to a predefined structure
125 * This works just like the regular cmd and arg fields of an ioctl.
127 struct ion_custom_data {
132 #define ION_IOC_MAGIC 'I'
135 * DOC: ION_IOC_ALLOC - allocate memory
137 * Takes an ion_allocation_data struct and returns it with the handle field
138 * populated with the opaque handle for the allocation.
140 #define ION_IOC_ALLOC _IOWR(ION_IOC_MAGIC, 0, \
141 struct ion_allocation_data)
144 * DOC: ION_IOC_FREE - free memory
146 * Takes an ion_handle_data struct and frees the handle.
148 #define ION_IOC_FREE _IOWR(ION_IOC_MAGIC, 1, struct ion_handle_data)
151 * DOC: ION_IOC_MAP - get a file descriptor to mmap
153 * Takes an ion_fd_data struct with the handle field populated with a valid
154 * opaque handle. Returns the struct with the fd field set to a file
155 * descriptor open in the current address space. This file descriptor
156 * can then be used as an argument to mmap.
158 #define ION_IOC_MAP _IOWR(ION_IOC_MAGIC, 2, struct ion_fd_data)
161 * DOC: ION_IOC_SHARE - creates a file descriptor to use to share an allocation
163 * Takes an ion_fd_data struct with the handle field populated with a valid
164 * opaque handle. Returns the struct with the fd field set to a file
165 * descriptor open in the current address space. This file descriptor
166 * can then be passed to another process. The corresponding opaque handle can
167 * be retrieved via ION_IOC_IMPORT.
169 #define ION_IOC_SHARE _IOWR(ION_IOC_MAGIC, 4, struct ion_fd_data)
172 * DOC: ION_IOC_IMPORT - imports a shared file descriptor
174 * Takes an ion_fd_data struct with the fd field populated with a valid file
175 * descriptor obtained from ION_IOC_SHARE and returns the struct with the handle
176 * filed set to the corresponding opaque handle.
178 #define ION_IOC_IMPORT _IOWR(ION_IOC_MAGIC, 5, struct ion_fd_data)
181 * DOC: ION_IOC_SYNC - syncs a shared file descriptors to memory
183 * Deprecated in favor of using the dma_buf api's correctly (syncing
184 * will happend automatically when the buffer is mapped to a device).
185 * If necessary should be used after touching a cached buffer from the cpu,
186 * this will make the buffer in memory coherent.
188 #define ION_IOC_SYNC _IOWR(ION_IOC_MAGIC, 7, struct ion_fd_data)
191 * DOC: ION_IOC_CUSTOM - call architecture specific ion ioctl
193 * Takes the argument of the architecture specific ioctl to call and
194 * passes appropriate userdata for that ioctl
196 #define ION_IOC_CUSTOM _IOWR(ION_IOC_MAGIC, 6, struct ion_custom_data)
198 #endif /* _UAPI_LINUX_ION_H */