ion.h revision 2991b7a044c82252e7b6456321515ebdbdf3acac
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_map_dma 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_kernel - create mapping for the given handle 163 * @client: the client 164 * @handle: handle to map 165 * 166 * Map the given handle into the kernel and return a kernel address that 167 * can be used to access this address. 168 */ 169void *ion_map_kernel(struct ion_client *client, struct ion_handle *handle); 170 171/** 172 * ion_unmap_kernel() - destroy a kernel mapping for a handle 173 * @client: the client 174 * @handle: handle to unmap 175 */ 176void ion_unmap_kernel(struct ion_client *client, struct ion_handle *handle); 177 178/** 179 * ion_map_dma - create a dma mapping for a given handle 180 * @client: the client 181 * @handle: handle to map 182 * 183 * Return an sg_table describing the given handle 184 */ 185struct sg_table *ion_map_dma(struct ion_client *client, 186 struct ion_handle *handle); 187 188/** 189 * ion_unmap_dma() - destroy a dma mapping for a handle 190 * @client: the client 191 * @handle: handle to unmap 192 */ 193void ion_unmap_dma(struct ion_client *client, struct ion_handle *handle); 194 195/** 196 * ion_share() - given a handle, obtain a buffer to pass to other clients 197 * @client: the client 198 * @handle: the handle to share 199 * 200 * Given a handle, return a buffer, which exists in a global name 201 * space, and can be passed to other clients. Should be passed into ion_import 202 * to obtain a new handle for this buffer. 203 * 204 * NOTE: This function does do not an extra reference. The burden is on the 205 * caller to make sure the buffer doesn't go away while it's being passed to 206 * another client. That is, ion_free should not be called on this handle until 207 * the buffer has been imported into the other client. 208 */ 209struct ion_buffer *ion_share(struct ion_client *client, 210 struct ion_handle *handle); 211 212/** 213 * ion_import() - given an buffer in another client, import it 214 * @client: this blocks client 215 * @buffer: the buffer to import (as obtained from ion_share) 216 * 217 * Given a buffer, add it to the client and return the handle to use to refer 218 * to it further. This is called to share a handle from one kernel client to 219 * another. 220 */ 221struct ion_handle *ion_import(struct ion_client *client, 222 struct ion_buffer *buffer); 223 224/** 225 * ion_import_fd() - given an fd obtained via ION_IOC_SHARE ioctl, import it 226 * @client: this blocks client 227 * @fd: the fd 228 * 229 * A helper function for drivers that will be recieving ion buffers shared 230 * with them from userspace. These buffers are represented by a file 231 * descriptor obtained as the return from the ION_IOC_SHARE ioctl. 232 * This function coverts that fd into the underlying buffer, and returns 233 * the handle to use to refer to it further. 234 */ 235struct ion_handle *ion_import_fd(struct ion_client *client, int fd); 236#endif /* __KERNEL__ */ 237 238/** 239 * DOC: Ion Userspace API 240 * 241 * create a client by opening /dev/ion 242 * most operations handled via following ioctls 243 * 244 */ 245 246/** 247 * struct ion_allocation_data - metadata passed from userspace for allocations 248 * @len: size of the allocation 249 * @align: required alignment of the allocation 250 * @flags: flags passed to heap 251 * @handle: pointer that will be populated with a cookie to use to refer 252 * to this allocation 253 * 254 * Provided by userspace as an argument to the ioctl 255 */ 256struct ion_allocation_data { 257 size_t len; 258 size_t align; 259 unsigned int flags; 260 struct ion_handle *handle; 261}; 262 263/** 264 * struct ion_fd_data - metadata passed to/from userspace for a handle/fd pair 265 * @handle: a handle 266 * @fd: a file descriptor representing that handle 267 * 268 * For ION_IOC_SHARE or ION_IOC_MAP userspace populates the handle field with 269 * the handle returned from ion alloc, and the kernel returns the file 270 * descriptor to share or map in the fd field. For ION_IOC_IMPORT, userspace 271 * provides the file descriptor and the kernel returns the handle. 272 */ 273struct ion_fd_data { 274 struct ion_handle *handle; 275 int fd; 276}; 277 278/** 279 * struct ion_handle_data - a handle passed to/from the kernel 280 * @handle: a handle 281 */ 282struct ion_handle_data { 283 struct ion_handle *handle; 284}; 285 286/** 287 * struct ion_custom_data - metadata passed to/from userspace for a custom ioctl 288 * @cmd: the custom ioctl function to call 289 * @arg: additional data to pass to the custom ioctl, typically a user 290 * pointer to a predefined structure 291 * 292 * This works just like the regular cmd and arg fields of an ioctl. 293 */ 294struct ion_custom_data { 295 unsigned int cmd; 296 unsigned long arg; 297}; 298 299#define ION_IOC_MAGIC 'I' 300 301/** 302 * DOC: ION_IOC_ALLOC - allocate memory 303 * 304 * Takes an ion_allocation_data struct and returns it with the handle field 305 * populated with the opaque handle for the allocation. 306 */ 307#define ION_IOC_ALLOC _IOWR(ION_IOC_MAGIC, 0, \ 308 struct ion_allocation_data) 309 310/** 311 * DOC: ION_IOC_FREE - free memory 312 * 313 * Takes an ion_handle_data struct and frees the handle. 314 */ 315#define ION_IOC_FREE _IOWR(ION_IOC_MAGIC, 1, struct ion_handle_data) 316 317/** 318 * DOC: ION_IOC_MAP - get a file descriptor to mmap 319 * 320 * Takes an ion_fd_data struct with the handle field populated with a valid 321 * opaque handle. Returns the struct with the fd field set to a file 322 * descriptor open in the current address space. This file descriptor 323 * can then be used as an argument to mmap. 324 */ 325#define ION_IOC_MAP _IOWR(ION_IOC_MAGIC, 2, struct ion_fd_data) 326 327/** 328 * DOC: ION_IOC_SHARE - creates a file descriptor to use to share an allocation 329 * 330 * Takes an ion_fd_data struct with the handle field populated with a valid 331 * opaque handle. Returns the struct with the fd field set to a file 332 * descriptor open in the current address space. This file descriptor 333 * can then be passed to another process. The corresponding opaque handle can 334 * be retrieved via ION_IOC_IMPORT. 335 */ 336#define ION_IOC_SHARE _IOWR(ION_IOC_MAGIC, 4, struct ion_fd_data) 337 338/** 339 * DOC: ION_IOC_IMPORT - imports a shared file descriptor 340 * 341 * Takes an ion_fd_data struct with the fd field populated with a valid file 342 * descriptor obtained from ION_IOC_SHARE and returns the struct with the handle 343 * filed set to the corresponding opaque handle. 344 */ 345#define ION_IOC_IMPORT _IOWR(ION_IOC_MAGIC, 5, int) 346 347/** 348 * DOC: ION_IOC_CUSTOM - call architecture specific ion ioctl 349 * 350 * Takes the argument of the architecture specific ioctl to call and 351 * passes appropriate userdata for that ioctl 352 */ 353#define ION_IOC_CUSTOM _IOWR(ION_IOC_MAGIC, 6, struct ion_custom_data) 354 355#endif /* _LINUX_ION_H */ 356