1 /* 2 * include/linux/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 22 struct 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 */ 32 enum 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__ 46 struct ion_device; 47 struct ion_heap; 48 struct ion_mapper; 49 struct ion_client; 50 struct 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 */ 69 struct 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 */ 84 struct ion_platform_data { 85 int nr; 86 struct ion_platform_heap heaps[]; 87 }; 88 89 /** 90 * ion_client_create() - allocate a client and returns it 91 * @dev: the global ion device 92 * @heap_mask: mask of heaps this client can allocate from 93 * @name: used for debugging 94 */ 95 struct ion_client *ion_client_create(struct ion_device *dev, 96 unsigned int heap_mask, const char *name); 97 98 /** 99 * ion_client_destroy() - free's a client and all it's handles 100 * @client: the client 101 * 102 * Free the provided client and all it's resources including 103 * any handles it is holding. 104 */ 105 void ion_client_destroy(struct ion_client *client); 106 107 /** 108 * ion_alloc - allocate ion memory 109 * @client: the client 110 * @len: size of the allocation 111 * @align: requested allocation alignment, lots of hardware blocks have 112 * alignment requirements of some kind 113 * @flags: mask of heaps to allocate from, if multiple bits are set 114 * heaps will be tried in order from lowest to highest order bit 115 * 116 * Allocate memory in one of the heaps provided in heap mask and return 117 * an opaque handle to it. 118 */ 119 struct ion_handle *ion_alloc(struct ion_client *client, size_t len, 120 size_t align, unsigned int flags); 121 122 /** 123 * ion_free - free a handle 124 * @client: the client 125 * @handle: the handle to free 126 * 127 * Free the provided handle. 128 */ 129 void ion_free(struct ion_client *client, struct ion_handle *handle); 130 131 /** 132 * ion_phys - returns the physical address and len of a handle 133 * @client: the client 134 * @handle: the handle 135 * @addr: a pointer to put the address in 136 * @len: a pointer to put the length in 137 * 138 * This function queries the heap for a particular handle to get the 139 * handle's physical address. It't output is only correct if 140 * a heap returns physically contiguous memory -- in other cases 141 * this api should not be implemented -- ion_map_dma should be used 142 * instead. Returns -EINVAL if the handle is invalid. This has 143 * no implications on the reference counting of the handle -- 144 * the returned value may not be valid if the caller is not 145 * holding a reference. 146 */ 147 int ion_phys(struct ion_client *client, struct ion_handle *handle, 148 ion_phys_addr_t *addr, size_t *len); 149 150 /** 151 * ion_map_kernel - create mapping for the given handle 152 * @client: the client 153 * @handle: handle to map 154 * 155 * Map the given handle into the kernel and return a kernel address that 156 * can be used to access this address. 157 */ 158 void *ion_map_kernel(struct ion_client *client, struct ion_handle *handle); 159 160 /** 161 * ion_unmap_kernel() - destroy a kernel mapping for a handle 162 * @client: the client 163 * @handle: handle to unmap 164 */ 165 void ion_unmap_kernel(struct ion_client *client, struct ion_handle *handle); 166 167 /** 168 * ion_map_dma - create a dma mapping for a given handle 169 * @client: the client 170 * @handle: handle to map 171 * 172 * Return an sglist describing the given handle 173 */ 174 struct scatterlist *ion_map_dma(struct ion_client *client, 175 struct ion_handle *handle); 176 177 /** 178 * ion_unmap_dma() - destroy a dma mapping for a handle 179 * @client: the client 180 * @handle: handle to unmap 181 */ 182 void ion_unmap_dma(struct ion_client *client, struct ion_handle *handle); 183 184 /** 185 * ion_share() - given a handle, obtain a buffer to pass to other clients 186 * @client: the client 187 * @handle: the handle to share 188 * 189 * Given a handle, return a buffer which exists in a global name 190 * space and can be passed to other clients. Should be passed into ion_import 191 * to obtain a new handle for this buffer. 192 */ 193 struct ion_buffer *ion_share(struct ion_client *client, 194 struct ion_handle *handle); 195 196 /** 197 * ion_import() - given an buffer in another client, import it 198 * @client: this blocks client 199 * @buffer: the buffer to import (as obtained from ion_share) 200 * 201 * Given a buffer, add it to the client and return the handle to use to refer 202 * to it further. This is called to share a handle from one kernel client to 203 * another. 204 */ 205 struct ion_handle *ion_import(struct ion_client *client, 206 struct ion_buffer *buffer); 207 208 /** 209 * ion_import_fd() - given an fd obtained via ION_IOC_SHARE ioctl, import it 210 * @client: this blocks client 211 * @fd: the fd 212 * 213 * A helper function for drivers that will be recieving ion buffers shared 214 * with them from userspace. These buffers are represented by a file 215 * descriptor obtained as the return from the ION_IOC_SHARE ioctl. 216 * This function coverts that fd into the underlying buffer, and returns 217 * the handle to use to refer to it further. 218 */ 219 struct ion_handle *ion_import_fd(struct ion_client *client, int fd); 220 #endif /* __KERNEL__ */ 221 222 /** 223 * DOC: Ion Userspace API 224 * 225 * create a client by opening /dev/ion 226 * most operations handled via following ioctls 227 * 228 */ 229 230 /** 231 * struct ion_allocation_data - metadata passed from userspace for allocations 232 * @len: size of the allocation 233 * @align: required alignment of the allocation 234 * @flags: flags passed to heap 235 * @handle: pointer that will be populated with a cookie to use to refer 236 * to this allocation 237 * 238 * Provided by userspace as an argument to the ioctl 239 */ 240 struct ion_allocation_data { 241 size_t len; 242 size_t align; 243 unsigned int flags; 244 struct ion_handle *handle; 245 }; 246 247 /** 248 * struct ion_fd_data - metadata passed to/from userspace for a handle/fd pair 249 * @handle: a handle 250 * @fd: a file descriptor representing that handle 251 * 252 * For ION_IOC_SHARE or ION_IOC_MAP userspace populates the handle field with 253 * the handle returned from ion alloc, and the kernel returns the file 254 * descriptor to share or map in the fd field. For ION_IOC_IMPORT, userspace 255 * provides the file descriptor and the kernel returns the handle. 256 */ 257 struct ion_fd_data { 258 struct ion_handle *handle; 259 int fd; 260 }; 261 262 /** 263 * struct ion_handle_data - a handle passed to/from the kernel 264 * @handle: a handle 265 */ 266 struct ion_handle_data { 267 struct ion_handle *handle; 268 }; 269 270 /** 271 * struct ion_custom_data - metadata passed to/from userspace for a custom ioctl 272 * @cmd: the custom ioctl function to call 273 * @arg: additional data to pass to the custom ioctl, typically a user 274 * pointer to a predefined structure 275 * 276 * This works just like the regular cmd and arg fields of an ioctl. 277 */ 278 struct ion_custom_data { 279 unsigned int cmd; 280 unsigned long arg; 281 }; 282 283 #define ION_IOC_MAGIC 'I' 284 285 /** 286 * DOC: ION_IOC_ALLOC - allocate memory 287 * 288 * Takes an ion_allocation_data struct and returns it with the handle field 289 * populated with the opaque handle for the allocation. 290 */ 291 #define ION_IOC_ALLOC _IOWR(ION_IOC_MAGIC, 0, \ 292 struct ion_allocation_data) 293 294 /** 295 * DOC: ION_IOC_FREE - free memory 296 * 297 * Takes an ion_handle_data struct and frees the handle. 298 */ 299 #define ION_IOC_FREE _IOWR(ION_IOC_MAGIC, 1, struct ion_handle_data) 300 301 /** 302 * DOC: ION_IOC_MAP - get a file descriptor to mmap 303 * 304 * Takes an ion_fd_data struct with the handle field populated with a valid 305 * opaque handle. Returns the struct with the fd field set to a file 306 * descriptor open in the current address space. This file descriptor 307 * can then be used as an argument to mmap. 308 */ 309 #define ION_IOC_MAP _IOWR(ION_IOC_MAGIC, 2, struct ion_fd_data) 310 311 /** 312 * DOC: ION_IOC_SHARE - creates a file descriptor to use to share an allocation 313 * 314 * Takes an ion_fd_data struct with the handle field populated with a valid 315 * opaque handle. Returns the struct with the fd field set to a file 316 * descriptor open in the current address space. This file descriptor 317 * can then be passed to another process. The corresponding opaque handle can 318 * be retrieved via ION_IOC_IMPORT. 319 */ 320 #define ION_IOC_SHARE _IOWR(ION_IOC_MAGIC, 4, struct ion_fd_data) 321 322 /** 323 * DOC: ION_IOC_IMPORT - imports a shared file descriptor 324 * 325 * Takes an ion_fd_data struct with the fd field populated with a valid file 326 * descriptor obtained from ION_IOC_SHARE and returns the struct with the handle 327 * filed set to the corresponding opaque handle. 328 */ 329 #define ION_IOC_IMPORT _IOWR(ION_IOC_MAGIC, 5, int) 330 331 /** 332 * DOC: ION_IOC_CUSTOM - call architecture specific ion ioctl 333 * 334 * Takes the argument of the architecture specific ioctl to call and 335 * passes appropriate userdata for that ioctl 336 */ 337 #define ION_IOC_CUSTOM _IOWR(ION_IOC_MAGIC, 6, struct ion_custom_data) 338 339 #endif /* _LINUX_ION_H */ 340
