ion.h revision ce1f147a2ed5ed468ad3a2f8418dddfd205d1fd9
1/* 2 * drivers/staging/android/ion/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 _LINUX_ION_H 18#define _LINUX_ION_H 19 20#include <linux/types.h> 21 22struct ion_handle; 23/** 24 * enum ion_heap_types - list of all possible types of heaps 25 * @ION_HEAP_TYPE_SYSTEM: memory allocated via vmalloc 26 * @ION_HEAP_TYPE_SYSTEM_CONTIG: memory allocated via kmalloc 27 * @ION_HEAP_TYPE_CARVEOUT: memory allocated from a prereserved 28 * carveout heap, allocations are physically 29 * contiguous 30 * @ION_HEAP_END: helper for iterating over heaps 31 */ 32enum ion_heap_type { 33 ION_HEAP_TYPE_SYSTEM, 34 ION_HEAP_TYPE_SYSTEM_CONTIG, 35 ION_HEAP_TYPE_CARVEOUT, 36 ION_HEAP_TYPE_CUSTOM, /* must be last so device specific heaps always 37 are at the end of this enum */ 38 ION_NUM_HEAPS, 39}; 40 41#define ION_HEAP_SYSTEM_MASK (1 << ION_HEAP_TYPE_SYSTEM) 42#define ION_HEAP_SYSTEM_CONTIG_MASK (1 << ION_HEAP_TYPE_SYSTEM_CONTIG) 43#define ION_HEAP_CARVEOUT_MASK (1 << ION_HEAP_TYPE_CARVEOUT) 44 45#ifdef __KERNEL__ 46struct ion_device; 47struct ion_heap; 48struct ion_mapper; 49struct ion_client; 50struct ion_buffer; 51 52/* This should be removed some day when phys_addr_t's are fully 53 plumbed in the kernel, and all instances of ion_phys_addr_t should 54 be converted to phys_addr_t. For the time being many kernel interfaces 55 do not accept phys_addr_t's that would have to */ 56#define ion_phys_addr_t unsigned long 57 58/** 59 * struct ion_platform_heap - defines a heap in the given platform 60 * @type: type of the heap from ion_heap_type enum 61 * @id: unique identifier for heap. When allocating (lower numbers 62 * will be allocated from first) 63 * @name: used for debug purposes 64 * @base: base address of heap in physical memory if applicable 65 * @size: size of the heap in bytes if applicable 66 * 67 * Provided by the board file. 68 */ 69struct ion_platform_heap { 70 enum ion_heap_type type; 71 unsigned int id; 72 const char *name; 73 ion_phys_addr_t base; 74 size_t size; 75}; 76 77/** 78 * struct ion_platform_data - array of platform heaps passed from board file 79 * @nr: number of structures in the array 80 * @heaps: array of platform_heap structions 81 * 82 * Provided by the board file in the form of platform data to a platform device. 83 */ 84struct ion_platform_data { 85 int nr; 86 struct ion_platform_heap heaps[]; 87}; 88 89/** 90 * ion_reserve() - reserve memory for ion heaps if applicable 91 * @data: platform data specifying starting physical address and 92 * size 93 * 94 * Calls memblock reserve to set aside memory for heaps that are 95 * located at specific memory addresses or of specfic sizes not 96 * managed by the kernel 97 */ 98void ion_reserve(struct ion_platform_data *data); 99 100/** 101 * ion_client_create() - allocate a client and returns it 102 * @dev: the global ion device 103 * @heap_mask: mask of heaps this client can allocate from 104 * @name: used for debugging 105 */ 106struct ion_client *ion_client_create(struct ion_device *dev, 107 unsigned int heap_mask, const char *name); 108 109/** 110 * ion_client_destroy() - free's a client and all it's handles 111 * @client: the client 112 * 113 * Free the provided client and all it's resources including 114 * any handles it is holding. 115 */ 116void ion_client_destroy(struct ion_client *client); 117 118/** 119 * ion_alloc - allocate ion memory 120 * @client: the client 121 * @len: size of the allocation 122 * @align: requested allocation alignment, lots of hardware blocks have 123 * alignment requirements of some kind 124 * @flags: mask of heaps to allocate from, if multiple bits are set 125 * heaps will be tried in order from lowest to highest order bit 126 * 127 * Allocate memory in one of the heaps provided in heap mask and return 128 * an opaque handle to it. 129 */ 130struct ion_handle *ion_alloc(struct ion_client *client, size_t len, 131 size_t align, unsigned int flags); 132 133/** 134 * ion_free - free a handle 135 * @client: the client 136 * @handle: the handle to free 137 * 138 * Free the provided handle. 139 */ 140void ion_free(struct ion_client *client, struct ion_handle *handle); 141 142/** 143 * ion_phys - returns the physical address and len of a handle 144 * @client: the client 145 * @handle: the handle 146 * @addr: a pointer to put the address in 147 * @len: a pointer to put the length in 148 * 149 * This function queries the heap for a particular handle to get the 150 * handle's physical address. It't output is only correct if 151 * a heap returns physically contiguous memory -- in other cases 152 * this api should not be implemented -- ion_sg_table should be used 153 * instead. Returns -EINVAL if the handle is invalid. This has 154 * no implications on the reference counting of the handle -- 155 * the returned value may not be valid if the caller is not 156 * holding a reference. 157 */ 158int ion_phys(struct ion_client *client, struct ion_handle *handle, 159 ion_phys_addr_t *addr, size_t *len); 160 161/** 162 * ion_map_dma - return an sg_table describing a handle 163 * @client: the client 164 * @handle: the handle 165 * 166 * This function returns the sg_table describing 167 * a particular ion handle. 168 */ 169struct sg_table *ion_sg_table(struct ion_client *client, 170 struct ion_handle *handle); 171 172/** 173 * ion_map_kernel - create mapping for the given handle 174 * @client: the client 175 * @handle: handle to map 176 * 177 * Map the given handle into the kernel and return a kernel address that 178 * can be used to access this address. 179 */ 180void *ion_map_kernel(struct ion_client *client, struct ion_handle *handle); 181 182/** 183 * ion_unmap_kernel() - destroy a kernel mapping for a handle 184 * @client: the client 185 * @handle: handle to unmap 186 */ 187void ion_unmap_kernel(struct ion_client *client, struct ion_handle *handle); 188 189/** 190 * ion_share_dma_buf() - given an ion client, create a dma-buf fd 191 * @client: the client 192 * @handle: the handle 193 */ 194int ion_share_dma_buf(struct ion_client *client, struct ion_handle *handle); 195 196/** 197 * ion_import_dma_buf() - given an dma-buf fd from the ion exporter get handle 198 * @client: the client 199 * @fd: the dma-buf fd 200 * 201 * Given an dma-buf fd that was allocated through ion via ion_share_dma_buf, 202 * import that fd and return a handle representing it. If a dma-buf from 203 * another exporter is passed in this function will return ERR_PTR(-EINVAL) 204 */ 205struct ion_handle *ion_import_dma_buf(struct ion_client *client, int fd); 206 207#endif /* __KERNEL__ */ 208 209/** 210 * DOC: Ion Userspace API 211 * 212 * create a client by opening /dev/ion 213 * most operations handled via following ioctls 214 * 215 */ 216 217/** 218 * struct ion_allocation_data - metadata passed from userspace for allocations 219 * @len: size of the allocation 220 * @align: required alignment of the allocation 221 * @flags: flags passed to heap 222 * @handle: pointer that will be populated with a cookie to use to refer 223 * to this allocation 224 * 225 * Provided by userspace as an argument to the ioctl 226 */ 227struct ion_allocation_data { 228 size_t len; 229 size_t align; 230 unsigned int flags; 231 struct ion_handle *handle; 232}; 233 234/** 235 * struct ion_fd_data - metadata passed to/from userspace for a handle/fd pair 236 * @handle: a handle 237 * @fd: a file descriptor representing that handle 238 * 239 * For ION_IOC_SHARE or ION_IOC_MAP userspace populates the handle field with 240 * the handle returned from ion alloc, and the kernel returns the file 241 * descriptor to share or map in the fd field. For ION_IOC_IMPORT, userspace 242 * provides the file descriptor and the kernel returns the handle. 243 */ 244struct ion_fd_data { 245 struct ion_handle *handle; 246 int fd; 247}; 248 249/** 250 * struct ion_handle_data - a handle passed to/from the kernel 251 * @handle: a handle 252 */ 253struct ion_handle_data { 254 struct ion_handle *handle; 255}; 256 257/** 258 * struct ion_custom_data - metadata passed to/from userspace for a custom ioctl 259 * @cmd: the custom ioctl function to call 260 * @arg: additional data to pass to the custom ioctl, typically a user 261 * pointer to a predefined structure 262 * 263 * This works just like the regular cmd and arg fields of an ioctl. 264 */ 265struct ion_custom_data { 266 unsigned int cmd; 267 unsigned long arg; 268}; 269 270#define ION_IOC_MAGIC 'I' 271 272/** 273 * DOC: ION_IOC_ALLOC - allocate memory 274 * 275 * Takes an ion_allocation_data struct and returns it with the handle field 276 * populated with the opaque handle for the allocation. 277 */ 278#define ION_IOC_ALLOC _IOWR(ION_IOC_MAGIC, 0, \ 279 struct ion_allocation_data) 280 281/** 282 * DOC: ION_IOC_FREE - free memory 283 * 284 * Takes an ion_handle_data struct and frees the handle. 285 */ 286#define ION_IOC_FREE _IOWR(ION_IOC_MAGIC, 1, struct ion_handle_data) 287 288/** 289 * DOC: ION_IOC_MAP - get a file descriptor to mmap 290 * 291 * Takes an ion_fd_data struct with the handle field populated with a valid 292 * opaque handle. Returns the struct with the fd field set to a file 293 * descriptor open in the current address space. This file descriptor 294 * can then be used as an argument to mmap. 295 */ 296#define ION_IOC_MAP _IOWR(ION_IOC_MAGIC, 2, struct ion_fd_data) 297 298/** 299 * DOC: ION_IOC_SHARE - creates a file descriptor to use to share an allocation 300 * 301 * Takes an ion_fd_data struct with the handle field populated with a valid 302 * opaque handle. Returns the struct with the fd field set to a file 303 * descriptor open in the current address space. This file descriptor 304 * can then be passed to another process. The corresponding opaque handle can 305 * be retrieved via ION_IOC_IMPORT. 306 */ 307#define ION_IOC_SHARE _IOWR(ION_IOC_MAGIC, 4, struct ion_fd_data) 308 309/** 310 * DOC: ION_IOC_IMPORT - imports a shared file descriptor 311 * 312 * Takes an ion_fd_data struct with the fd field populated with a valid file 313 * descriptor obtained from ION_IOC_SHARE and returns the struct with the handle 314 * filed set to the corresponding opaque handle. 315 */ 316#define ION_IOC_IMPORT _IOWR(ION_IOC_MAGIC, 5, int) 317 318/** 319 * DOC: ION_IOC_CUSTOM - call architecture specific ion ioctl 320 * 321 * Takes the argument of the architecture specific ioctl to call and 322 * passes appropriate userdata for that ioctl 323 */ 324#define ION_IOC_CUSTOM _IOWR(ION_IOC_MAGIC, 6, struct ion_custom_data) 325 326#endif /* _LINUX_ION_H */ 327