1 /* 2 * drivers/staging/android/uapi/ion.h 3 * 4 * Copyright (C) 2011 Google, Inc. 5 * 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. 9 * 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. 14 * 15 */ 16 17 #ifndef _UAPI_LINUX_ION_H 18 #define _UAPI_LINUX_ION_H 19 20 #include <linux/ioctl.h> 21 #include <linux/types.h> 22 23 typedef int ion_user_handle_t; 24 25 /** 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 31 * contiguous 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 36 */ 37 enum ion_heap_type { 38 ION_HEAP_TYPE_SYSTEM, 39 ION_HEAP_TYPE_SYSTEM_CONTIG, 40 ION_HEAP_TYPE_CARVEOUT, 41 ION_HEAP_TYPE_CHUNK, 42 ION_HEAP_TYPE_DMA, 43 ION_HEAP_TYPE_CUSTOM, /* 44 * must be last so device specific heaps always 45 * are at the end of this enum 46 */ 47 ION_NUM_HEAPS = 16, 48 }; 49 50 #define ION_HEAP_SYSTEM_MASK (1 << ION_HEAP_TYPE_SYSTEM) 51 #define ION_HEAP_SYSTEM_CONTIG_MASK (1 << ION_HEAP_TYPE_SYSTEM_CONTIG) 52 #define ION_HEAP_CARVEOUT_MASK (1 << ION_HEAP_TYPE_CARVEOUT) 53 #define ION_HEAP_TYPE_DMA_MASK (1 << ION_HEAP_TYPE_DMA) 54 55 #define ION_NUM_HEAP_IDS (sizeof(unsigned int) * 8) 56 57 /** 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. 60 */ 61 #define ION_FLAG_CACHED 1 /* 62 * mappings of this buffer should be 63 * cached, ion will do cache 64 * maintenance when the buffer is 65 * mapped for dma 66 */ 67 #define ION_FLAG_CACHED_NEEDS_SYNC 2 /* 68 * mappings of this buffer will created 69 * at mmap time, if this is set 70 * caches must be managed 71 * manually 72 */ 73 74 /** 75 * DOC: Ion Userspace API 76 * 77 * create a client by opening /dev/ion 78 * most operations handled via following ioctls 79 * 80 */ 81 82 /** 83 * struct ion_allocation_data - metadata passed from userspace for allocations 84 * @len: size of the allocation 85 * @align: required alignment of the allocation 86 * @heap_id_mask: mask of heap ids to allocate from 87 * @flags: flags passed to heap 88 * @handle: pointer that will be populated with a cookie to use to 89 * refer to this allocation 90 * 91 * Provided by userspace as an argument to the ioctl 92 */ 93 struct ion_allocation_data { 94 size_t len; 95 size_t align; 96 unsigned int heap_id_mask; 97 unsigned int flags; 98 ion_user_handle_t handle; 99 }; 100 101 /** 102 * struct ion_fd_data - metadata passed to/from userspace for a handle/fd pair 103 * @handle: a handle 104 * @fd: a file descriptor representing that handle 105 * 106 * For ION_IOC_SHARE or ION_IOC_MAP userspace populates the handle field with 107 * the handle returned from ion alloc, and the kernel returns the file 108 * descriptor to share or map in the fd field. For ION_IOC_IMPORT, userspace 109 * provides the file descriptor and the kernel returns the handle. 110 */ 111 struct ion_fd_data { 112 ion_user_handle_t handle; 113 int fd; 114 }; 115 116 /** 117 * struct ion_handle_data - a handle passed to/from the kernel 118 * @handle: a handle 119 */ 120 struct ion_handle_data { 121 ion_user_handle_t handle; 122 }; 123 124 /** 125 * struct ion_custom_data - metadata passed to/from userspace for a custom ioctl 126 * @cmd: the custom ioctl function to call 127 * @arg: additional data to pass to the custom ioctl, typically a user 128 * pointer to a predefined structure 129 * 130 * This works just like the regular cmd and arg fields of an ioctl. 131 */ 132 struct ion_custom_data { 133 unsigned int cmd; 134 unsigned long arg; 135 }; 136 137 #define ION_IOC_MAGIC 'I' 138 139 /** 140 * DOC: ION_IOC_ALLOC - allocate memory 141 * 142 * Takes an ion_allocation_data struct and returns it with the handle field 143 * populated with the opaque handle for the allocation. 144 */ 145 #define ION_IOC_ALLOC _IOWR(ION_IOC_MAGIC, 0, \ 146 struct ion_allocation_data) 147 148 /** 149 * DOC: ION_IOC_FREE - free memory 150 * 151 * Takes an ion_handle_data struct and frees the handle. 152 */ 153 #define ION_IOC_FREE _IOWR(ION_IOC_MAGIC, 1, struct ion_handle_data) 154 155 /** 156 * DOC: ION_IOC_MAP - get a file descriptor to mmap 157 * 158 * Takes an ion_fd_data struct with the handle field populated with a valid 159 * opaque handle. Returns the struct with the fd field set to a file 160 * descriptor open in the current address space. This file descriptor 161 * can then be used as an argument to mmap. 162 */ 163 #define ION_IOC_MAP _IOWR(ION_IOC_MAGIC, 2, struct ion_fd_data) 164 165 /** 166 * DOC: ION_IOC_SHARE - creates a file descriptor to use to share an allocation 167 * 168 * Takes an ion_fd_data struct with the handle field populated with a valid 169 * opaque handle. Returns the struct with the fd field set to a file 170 * descriptor open in the current address space. This file descriptor 171 * can then be passed to another process. The corresponding opaque handle can 172 * be retrieved via ION_IOC_IMPORT. 173 */ 174 #define ION_IOC_SHARE _IOWR(ION_IOC_MAGIC, 4, struct ion_fd_data) 175 176 /** 177 * DOC: ION_IOC_IMPORT - imports a shared file descriptor 178 * 179 * Takes an ion_fd_data struct with the fd field populated with a valid file 180 * descriptor obtained from ION_IOC_SHARE and returns the struct with the handle 181 * filed set to the corresponding opaque handle. 182 */ 183 #define ION_IOC_IMPORT _IOWR(ION_IOC_MAGIC, 5, struct ion_fd_data) 184 185 /** 186 * DOC: ION_IOC_SYNC - syncs a shared file descriptors to memory 187 * 188 * Deprecated in favor of using the dma_buf api's correctly (syncing 189 * will happen automatically when the buffer is mapped to a device). 190 * If necessary should be used after touching a cached buffer from the cpu, 191 * this will make the buffer in memory coherent. 192 */ 193 #define ION_IOC_SYNC _IOWR(ION_IOC_MAGIC, 7, struct ion_fd_data) 194 195 /** 196 * DOC: ION_IOC_CUSTOM - call architecture specific ion ioctl 197 * 198 * Takes the argument of the architecture specific ioctl to call and 199 * passes appropriate userdata for that ioctl 200 */ 201 #define ION_IOC_CUSTOM _IOWR(ION_IOC_MAGIC, 6, struct ion_custom_data) 202 203 #endif /* _UAPI_LINUX_ION_H */ 204
