1/* 2 * Copyright © 2021 NVIDIA Corporation 3 * 4 * Permission is hereby granted, free of charge, to any person obtaining a 5 * copy of this software and associated documentation files (the "Software"), 6 * to deal in the Software without restriction, including without limitation 7 * the rights to use, copy, modify, merge, publish, distribute, sublicense, 8 * and/or sell copies of the Software, and to permit persons to whom the 9 * Software is furnished to do so, subject to the following conditions: 10 * 11 * The above copyright notice and this permission notice (including the next 12 * paragraph) shall be included in all copies or substantial portions of the 13 * Software. 14 * 15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, 16 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 17 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND 18 * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT 19 * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, 20 * WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, 21 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER 22 * DEALINGS IN THE SOFTWARE. 23 */ 24 25#include "gbm_backend_abi.h" /* Current GBM backend ABI implementation */ 26 27#include <stddef.h> /* offsetof */ 28#include <stdio.h> /* printf */ 29 30/* 31 * The following are previous implementations of the structures defined in 32 * gbm_backend_abi.h, with their ABI version appended. 33 * 34 * DO NOT EVER CHANGE EXISTING DEFINITIONS HERE! 35 * 36 * Changing them implies breaking the GBM backend ABI. Instead, to extend the 37 * ABI, in gbm_backend_abi.h: 38 * 39 * -Add a new versioned struct 40 * -Append it to the associated top-level object's struct 41 * -Increment GBM_BACKEND_ABI_VERSION 42 * 43 * Then, here: 44 * 45 * -Add a new block of definitions below for the new ABI content 46 * -Add a new block of checks in main() 47 */ 48 49/* 50 * From: Simon Ser - "gbm: assume USE_SCANOUT in create_with_modifiers" 51 * 52 * Note: ABI 1 is identical to ABI 0, except gbm_device_v0.bo_create can 53 * provide both modifiers and usage. 54 */ 55#define GBM_BACKEND_ABI_VERSION_abi0 1 56struct gbm_device_v0_abi0 { 57 const struct gbm_backend_desc *backend_desc; 58 uint32_t backend_version; 59 int fd; 60 const char *name; 61 void (*destroy)(struct gbm_device *gbm); 62 int (*is_format_supported)(struct gbm_device *gbm, 63 uint32_t format, 64 uint32_t usage); 65 int (*get_format_modifier_plane_count)(struct gbm_device *device, 66 uint32_t format, 67 uint64_t modifier); 68 struct gbm_bo *(*bo_create)(struct gbm_device *gbm, 69 uint32_t width, uint32_t height, 70 uint32_t format, 71 uint32_t usage, 72 const uint64_t *modifiers, 73 const unsigned int count); 74 struct gbm_bo *(*bo_import)(struct gbm_device *gbm, uint32_t type, 75 void *buffer, uint32_t usage); 76 void *(*bo_map)(struct gbm_bo *bo, 77 uint32_t x, uint32_t y, 78 uint32_t width, uint32_t height, 79 uint32_t flags, uint32_t *stride, 80 void **map_data); 81 void (*bo_unmap)(struct gbm_bo *bo, void *map_data); 82 int (*bo_write)(struct gbm_bo *bo, const void *buf, size_t data); 83 int (*bo_get_fd)(struct gbm_bo *bo); 84 int (*bo_get_planes)(struct gbm_bo *bo); 85 union gbm_bo_handle (*bo_get_handle)(struct gbm_bo *bo, int plane); 86 int (*bo_get_plane_fd)(struct gbm_bo *bo, int plane); 87 uint32_t (*bo_get_stride)(struct gbm_bo *bo, int plane); 88 uint32_t (*bo_get_offset)(struct gbm_bo *bo, int plane); 89 uint64_t (*bo_get_modifier)(struct gbm_bo *bo); 90 void (*bo_destroy)(struct gbm_bo *bo); 91 struct gbm_surface *(*surface_create)(struct gbm_device *gbm, 92 uint32_t width, uint32_t height, 93 uint32_t format, uint32_t flags, 94 const uint64_t *modifiers, 95 const unsigned count); 96 struct gbm_bo *(*surface_lock_front_buffer)(struct gbm_surface *surface); 97 void (*surface_release_buffer)(struct gbm_surface *surface, 98 struct gbm_bo *bo); 99 int (*surface_has_free_buffers)(struct gbm_surface *surface); 100 void (*surface_destroy)(struct gbm_surface *surface); 101}; 102 103struct gbm_device_abi0 { 104 /* Hack to make a gbm_device detectable by its first element. */ 105 struct gbm_device *(*dummy)(int); 106 struct gbm_device_v0_abi0 v0; 107}; 108 109/** 110 * GBM buffer object interface corresponding to GBM_BACKEND_ABI_VERSION = 0 111 * 112 * DO NOT MODIFY THIS STRUCT. Instead, introduce a gbm_bo_v1, increment 113 * GBM_BACKEND_ABI_VERSION, and append gbm_bo_v1 to gbm_bo. 114 */ 115struct gbm_bo_v0_abi0 { 116 uint32_t width; 117 uint32_t height; 118 uint32_t stride; 119 uint32_t format; 120 union gbm_bo_handle handle; 121 void *user_data; 122 void (*destroy_user_data)(struct gbm_bo *, void *); 123}; 124 125/** 126 * The allocated buffer object. 127 * 128 * The members in this structure should not be accessed directly. 129 * 130 * To modify this structure, introduce a new gbm_bo_v<N> structure, add it to 131 * the end of this structure, and increment GBM_BACKEND_ABI_VERSION. 132 */ 133struct gbm_bo_abi0 { 134 struct gbm_device *gbm; 135 struct gbm_bo_v0_abi0 v0; 136}; 137 138/** 139 * GBM surface interface corresponding to GBM_BACKEND_ABI_VERSION = 0 140 * 141 * DO NOT MODIFY THIS STRUCT. Instead, introduce a gbm_surface_v1, increment 142 * GBM_BACKEND_ABI_VERSION, and append gbm_surface_v1 to gbm_surface. 143 */ 144struct gbm_surface_v0_abi0 { 145 uint32_t width; 146 uint32_t height; 147 uint32_t format; 148 uint32_t flags; 149 struct { 150 uint64_t *modifiers; 151 unsigned count; 152 }; 153}; 154 155/** 156 * An allocated GBM surface. 157 * 158 * To modify this structure, introduce a new gbm_surface_v<N> structure, add it 159 * to the end of this structure, and increment GBM_BACKEND_ABI_VERSION. 160 */ 161struct gbm_surface_abi0 { 162 struct gbm_device *gbm; 163 struct gbm_surface_v0_abi0 v0; 164}; 165 166/** 167 * GBM backend interfaces corresponding to GBM_BACKEND_ABI_VERSION = 0 168 * 169 * DO NOT MODIFY THIS STRUCT. Instead, introduce a gbm_backend_v1, increment 170 * GBM_BACKEND_ABI_VERSION, append gbm_backend_v1 to gbm_backend. 171 */ 172struct gbm_backend_v0_abi0 { 173 /** 174 * The version of the GBM backend interface supported by this backend. This 175 * is set by the backend itself, and may be greater or less than the version 176 * supported by the loader. It is the responsibility of the GBM loader to 177 * respect this version when accessing fields in this structure. 178 */ 179 uint32_t backend_version; 180 181 const char *backend_name; 182 struct gbm_device *(*create_device)(int fd, uint32_t gbm_backend_version); 183}; 184 185/** 186 * The interface exposed by an external GBM backend. 187 * 188 * To modify this structure, introduce a new gbm_backend_v<N> structure, add it 189 * to the end of this structure, and increment GBM_BACKEND_ABI_VERSION. 190 */ 191struct gbm_backend_abi0 { 192 struct gbm_backend_v0_abi0 v0; 193}; 194 195/** 196 * GBM interfaces exposed to GBM backends at GBM_BACKEND_ABI_VERSION >= 0 197 * 198 * DO NOT MODIFY THIS STRUCT. Instead, introduce a gbm_core_v1, increment 199 * GBM_BACKEND_ABI_VERSION, and append gbm_core_v1 to gbm_backend. 200 */ 201struct gbm_core_v0_abi0 { 202 /** 203 * The version of the GBM backend interface supported by the GBM loader. This 204 * is set by the loader, and may be greater or less than the version 205 * supported by a given backend. It is the responsibility of the backend to 206 * respect this version when accessing fields in this structure and other 207 * structures allocated or modified by the loader. 208 */ 209 uint32_t core_version; 210 211 uint32_t (*format_canonicalize)(uint32_t gbm_format); 212}; 213 214/** 215 * The interface exposed by the GBM core/loader code to GBM backends. 216 * 217 * To modify this structure, introduce a new gbm_core_v<N> structure, add it 218 * to the end of this structure, and increment GBM_BACKEND_ABI_VERSION. 219 */ 220struct gbm_core_abi0 { 221 struct gbm_core_v0_abi0 v0; 222}; 223 224typedef const struct gbm_backend *(*GBM_GET_BACKEND_PROC_PTR_abi0)(const struct gbm_core *gbm_core); 225 226/* 227 * Structure/member ABI-checking helper macros 228 */ 229#define MEMBER_SIZE(type, member) sizeof(((type *)0)->member) 230 231#define CHECK_RENAMED_MEMBER_BASE(type, a_ver, b_ver, a_member, b_member) \ 232 do { \ 233 if (offsetof(struct type ## a_ver, a_member) != \ 234 offsetof(struct type ## b_ver, b_member)) { \ 235 printf("Backards incompatible change detected!\n " \ 236 "offsetof(struct " #type #a_ver "::" #a_member ") != " \ 237 "offsetof(struct " #type #b_ver "::" #b_member ")\n"); \ 238 return 1; \ 239 } \ 240 \ 241 if (MEMBER_SIZE(struct type ## a_ver, a_member) != \ 242 MEMBER_SIZE(struct type ## b_ver, b_member)) { \ 243 printf("Backards incompatible change detected!\n " \ 244 "MEMBER_SIZE(struct " #type #a_ver "::" #a_member ") != " \ 245 "MEMBER_SIZE(struct " #type #b_ver "::" #b_member ")\n"); \ 246 return 1; \ 247 } \ 248 } while (0) 249 250#define CHECK_RENAMED_MEMBER_TYPE(type, a_ver, b_ver, a_member, b_member) \ 251 do { \ 252 /* Compile-time type compatibility check */ \ 253 struct type ## a_ver a; \ 254 struct type ## b_ver b = {0}; \ 255 a.a_member = b.b_member; \ 256 (void)a; \ 257 } while (0) 258 259#define CHECK_RENAMED_MEMBER(type, a_ver, b_ver, a_member, b_member) \ 260 do { \ 261 CHECK_RENAMED_MEMBER_BASE(type, a_ver, b_ver, a_member, b_member); \ 262 CHECK_RENAMED_MEMBER_TYPE(type, a_ver, b_ver, a_member, b_member); \ 263 } while (0) 264#define CHECK_RENAMED_MEMBER_NO_TYPE(type, a_ver, b_ver, a_member, b_member) \ 265 CHECK_RENAMED_MEMBER_BASE(type, a_ver, b_ver, a_member, b_member); 266 267#define CHECK_MEMBER(type, a_ver, b_ver, member) \ 268 CHECK_RENAMED_MEMBER(type, a_ver, b_ver, member, member) 269#define CHECK_MEMBER_NO_TYPE(type, a_ver, b_ver, member) \ 270 CHECK_RENAMED_MEMBER_NO_TYPE(type, a_ver, b_ver, member, member) 271#define CHECK_MEMBER_CURRENT(type, a_ver, member) \ 272 CHECK_MEMBER(type, a_ver,, member) 273#define CHECK_MEMBER_CURRENT_NO_TYPE(type, a_ver, member) \ 274 CHECK_MEMBER_NO_TYPE(type, a_ver,, member) 275 276#define CHECK_SIZE(type, a_ver, b_ver) \ 277 do { \ 278 if (sizeof(struct type ## a_ver) > \ 279 sizeof(struct type ## b_ver)) { \ 280 printf("Backards incompatible change detected!\n " \ 281 "sizeof(struct " #type #a_ver ") > " \ 282 "sizeof(struct " #type #b_ver ")\n"); \ 283 return 1; \ 284 } \ 285 } while (0) 286 287#define CHECK_SIZE_CURRENT(type, a_ver) \ 288 do { \ 289 if (sizeof(struct type ## a_ver) != \ 290 sizeof(struct type)) { \ 291 printf("Backards incompatible change detected!\n " \ 292 "sizeof(struct " #type #a_ver ") != " \ 293 "sizeof(struct " #type ")\n"); \ 294 return 1; \ 295 } \ 296 } while (0) 297 298#define CHECK_VERSION(a_ver, b_ver) \ 299 do { \ 300 if ((GBM_BACKEND_ABI_VERSION ## a_ver) >= \ 301 (GBM_BACKEND_ABI_VERSION ## b_ver)) { \ 302 printf("Backards incompatible change detected!\n " \ 303 "GBM_BACKEND_ABI_VERSION" #a_ver " >= " \ 304 "GBM_BACKEND_ABI_VERSION" #b_ver "\n"); \ 305 return 1; \ 306 } \ 307 } while (0) 308 309#define CHECK_VERSION_CURRENT(a_ver) \ 310 do { \ 311 if ((GBM_BACKEND_ABI_VERSION ## a_ver) != \ 312 (GBM_BACKEND_ABI_VERSION)) { \ 313 printf("Backards incompatible change detected!\n " \ 314 "GBM_BACKEND_ABI_VERSION" #a_ver " != " \ 315 "GBM_BACKEND_ABI_VERSION\n"); \ 316 return 1; \ 317 } \ 318 } while (0) 319 320#define CHECK_PROC(proc, a_ver, b_ver) \ 321 do { \ 322 proc ## a_ver a; \ 323 proc ## b_ver b = NULL; \ 324 a = b; \ 325 (void)a; \ 326 } while (0) 327 328#define CHECK_PROC_CURRENT(proc, a_ver) \ 329 CHECK_PROC(proc, a_ver,) 330 331int main(int argc, char **argv) 332{ 333 /********************************************/ 334 /*** Compare Current ABI to ABI version 0 ***/ 335 /********************************************/ 336 337 /* Check current gbm_device ABI against gbm_device_abi0*/ 338 CHECK_MEMBER_CURRENT(gbm_device, _abi0, dummy); 339 CHECK_MEMBER_CURRENT_NO_TYPE(gbm_device, _abi0, v0); 340 341 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, backend_desc); 342 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, backend_version); 343 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, fd); 344 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, name); 345 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, destroy); 346 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, is_format_supported); 347 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, get_format_modifier_plane_count); 348 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, bo_create); 349 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, bo_import); 350 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, bo_map); 351 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, bo_unmap); 352 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, bo_write); 353 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, bo_get_fd); 354 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, bo_get_planes); 355 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, bo_get_handle); 356 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, bo_get_plane_fd); 357 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, bo_get_stride); 358 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, bo_get_offset); 359 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, bo_get_modifier); 360 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, bo_destroy); 361 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, surface_create); 362 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, surface_lock_front_buffer); 363 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, surface_release_buffer); 364 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, surface_has_free_buffers); 365 CHECK_MEMBER_CURRENT(gbm_device_v0, _abi0, surface_destroy); 366 367 /* Size of ABI-versioned substructures verified by above member checks */ 368 CHECK_SIZE_CURRENT (gbm_device, _abi0); 369 370 371 /* Check current gbm_bo ABI against gbm_bo_abi0*/ 372 CHECK_MEMBER_CURRENT(gbm_bo, _abi0, gbm); 373 CHECK_MEMBER_CURRENT_NO_TYPE(gbm_bo, _abi0, v0); 374 375 CHECK_MEMBER_CURRENT(gbm_bo_v0, _abi0, width); 376 CHECK_MEMBER_CURRENT(gbm_bo_v0, _abi0, height); 377 CHECK_MEMBER_CURRENT(gbm_bo_v0, _abi0, stride); 378 CHECK_MEMBER_CURRENT(gbm_bo_v0, _abi0, format); 379 CHECK_MEMBER_CURRENT(gbm_bo_v0, _abi0, handle); 380 CHECK_MEMBER_CURRENT(gbm_bo_v0, _abi0, user_data); 381 CHECK_MEMBER_CURRENT(gbm_bo_v0, _abi0, destroy_user_data); 382 383 /* Size of ABI-versioned substructures verified by above member checks */ 384 CHECK_SIZE_CURRENT (gbm_bo, _abi0); 385 386 387 /* Check current gbm_surface ABI against gbm_surface_abi0 */ 388 CHECK_MEMBER_CURRENT(gbm_surface, _abi0, gbm); 389 CHECK_MEMBER_CURRENT_NO_TYPE(gbm_surface, _abi0, v0); 390 391 CHECK_MEMBER_CURRENT(gbm_surface_v0, _abi0, width); 392 CHECK_MEMBER_CURRENT(gbm_surface_v0, _abi0, height); 393 CHECK_MEMBER_CURRENT(gbm_surface_v0, _abi0, format); 394 CHECK_MEMBER_CURRENT(gbm_surface_v0, _abi0, flags); 395 CHECK_MEMBER_CURRENT(gbm_surface_v0, _abi0, modifiers); 396 CHECK_MEMBER_CURRENT(gbm_surface_v0, _abi0, count); 397 398 /* Size of ABI-versioned substructures verified by above member checks */ 399 CHECK_SIZE_CURRENT (gbm_surface, _abi0); 400 401 402 /* Check current gbm_backend ABI against gbm_backend_abi0 */ 403 CHECK_MEMBER_CURRENT_NO_TYPE(gbm_backend, _abi0, v0); 404 405 CHECK_MEMBER_CURRENT(gbm_backend_v0, _abi0, backend_version); 406 CHECK_MEMBER_CURRENT(gbm_backend_v0, _abi0, backend_name); 407 CHECK_MEMBER_CURRENT(gbm_backend_v0, _abi0, create_device); 408 409 /* Size of ABI-versioned substructures verified by above member checks */ 410 CHECK_SIZE_CURRENT (gbm_backend, _abi0); 411 412 413 /* Check current gbm_core ABI against gbm_core_abi0 */ 414 CHECK_MEMBER_CURRENT_NO_TYPE(gbm_core, _abi0, v0); 415 416 CHECK_MEMBER_CURRENT(gbm_core_v0, _abi0, core_version); 417 CHECK_MEMBER_CURRENT(gbm_core_v0, _abi0, format_canonicalize); 418 419 /* Size of ABI-versioned substructures verified by above member checks */ 420 CHECK_SIZE_CURRENT (gbm_core, _abi0); 421 422 423 CHECK_PROC_CURRENT (GBM_GET_BACKEND_PROC_PTR, _abi0); 424 425 return 0; 426} 427