src/gbm/main/gbm.c

   1 /*
   2  * Copyright © 2011 Intel 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  * Authors:
  25  *    Benjamin Franzke <benjaminfranzke@googlemail.com>
  26  */
  27
  28 #define _BSD_SOURCE
  29 #define _DEFAULT_SOURCE
  30
  31 #include <stddef.h>
  32 #include <stdio.h>
  33 #include <stdlib.h>
  34 #include <string.h>
  35 #include <stdint.h>
  36
  37 #include <sys/types.h>
  38 #include <sys/stat.h>
  39 #include <unistd.h>
  40 #include <errno.h>
  41
  42 #include "gbm.h"
  43 #include "gbmint.h"
  44 #include "backend.h"
  45
  46 #define ARRAY_SIZE(a) (sizeof(a)/sizeof((a)[0]))
  47
  48 static struct gbm_device *devices[16];
  49
  50 static int device_num = 0;
  51
  52 /** Returns the file description for the gbm device
  53  *
  54  * \return The fd that the struct gbm_device was created with
  55  */
  56 GBM_EXPORT int
  57 gbm_device_get_fd(struct gbm_device *gbm)
  58 {
  59    return gbm->fd;
  60 }
  61
  62 /* FIXME: maybe superfluous, use udev subclass from the fd? */
  63 /** Get the backend name for the given gbm device
  64  *
  65  * \return The backend name string - this belongs to the device and must not
  66  * be freed
  67  */
  68 GBM_EXPORT const char *
  69 gbm_device_get_backend_name(struct gbm_device *gbm)
  70 {
  71    return gbm->name;
  72 }
  73
  74 /** Test if a format is supported for a given set of usage flags.
  75  *
  76  * \param gbm The created buffer manager
  77  * \param format The format to test
  78  * \param usage A bitmask of the usages to test the format against
  79  * \return 1 if the format is supported otherwise 0
  80  *
  81  * \sa enum gbm_bo_flags for the list of flags that the format can be
  82  * tested against
  83  *
  84  * \sa enum gbm_bo_format for the list of formats
  85  */
  86 GBM_EXPORT int
  87 gbm_device_is_format_supported(struct gbm_device *gbm,
  88                                uint32_t format, uint32_t usage)
  89 {
  90    return gbm->is_format_supported(gbm, format, usage);
  91 }
  92
  93 /** Destroy the gbm device and free all resources associated with it.
  94  *
  95  * \param gbm The device created using gbm_create_device()
  96  */
  97 GBM_EXPORT void
  98 gbm_device_destroy(struct gbm_device *gbm)
  99 {
 100    gbm->refcount--;
 101    if (gbm->refcount == 0)
 102       gbm->destroy(gbm);
 103 }
 104
 105 struct gbm_device *
 106 _gbm_mesa_get_device(int fd)
 107 {
 108    struct gbm_device *gbm = NULL;
 109    struct stat buf;
 110    dev_t dev;
 111    int i;
 112
 113    if (fd < 0 || fstat(fd, &buf) < 0 || !S_ISCHR(buf.st_mode)) {
 114       errno = EINVAL;
 115       return NULL;
 116    }
 117
 118    for (i = 0; i < device_num; ++i) {
 119       dev = devices[i]->stat.st_rdev;
 120       if (major(dev) == major(buf.st_rdev) &&
 121           minor(dev) == minor(buf.st_rdev)) {
 122          gbm = devices[i];
 123          gbm->refcount++;
 124          break;
 125       }
 126    }
 127
 128    return gbm;
 129 }
 130
 131 /** Create a gbm device for allocating buffers
 132  *
 133  * The file descriptor passed in is used by the backend to communicate with
 134  * platform for allocating the memory. For allocations using DRI this would be
 135  * the file descriptor returned when opening a device such as \c
 136  * /dev/dri/card0
 137  *
 138  * \param fd The file descriptor for an backend specific device
 139  * \return The newly created struct gbm_device. The resources associated with
 140  * the device should be freed with gbm_device_destroy() when it is no longer
 141  * needed. If the creation of the device failed NULL will be returned.
 142  */
 143 GBM_EXPORT struct gbm_device *
 144 gbm_create_device(int fd)
 145 {
 146    struct gbm_device *gbm = NULL;
 147    struct stat buf;
 148
 149    if (fd < 0 || fstat(fd, &buf) < 0 || !S_ISCHR(buf.st_mode)) {
 150       errno = EINVAL;
 151       return NULL;
 152    }
 153
 154    if (device_num == 0)
 155       memset(devices, 0, sizeof devices);
 156
 157    gbm = _gbm_create_device(fd);
 158    if (gbm == NULL)
 159       return NULL;
 160
 161    gbm->dummy = gbm_create_device;
 162    gbm->stat = buf;
 163    gbm->refcount = 1;
 164
 165    if (device_num < ARRAY_SIZE(devices)-1)
 166       devices[device_num++] = gbm;
 167
 168    return gbm;
 169 }
 170
 171 /** Get the width of the buffer object
 172  *
 173  * \param bo The buffer object
 174  * \return The width of the allocated buffer object
 175  *
 176  */
 177 GBM_EXPORT unsigned int
 178 gbm_bo_get_width(struct gbm_bo *bo)
 179 {
 180    return bo->width;
 181 }
 182
 183 /** Get the height of the buffer object
 184  *
 185  * \param bo The buffer object
 186  * \return The height of the allocated buffer object
 187  */
 188 GBM_EXPORT unsigned int
 189 gbm_bo_get_height(struct gbm_bo *bo)
 190 {
 191    return bo->height;
 192 }
 193
 194 /** Get the stride of the buffer object
 195  *
 196  * This is calculated by the backend when it does the allocation in
 197  * gbm_bo_create()
 198  *
 199  * \param bo The buffer object
 200  * \return The stride of the allocated buffer object in bytes
 201  */
 202 GBM_EXPORT uint32_t
 203 gbm_bo_get_stride(struct gbm_bo *bo)
 204 {
 205    return bo->stride;
 206 }
 207
 208 /** Get the format of the buffer object
 209  *
 210  * The format of the pixels in the buffer.
 211  *
 212  * \param bo The buffer object
 213  * \return The format of buffer object, on of the GBM_FORMAT_* codes
 214  */
 215 GBM_EXPORT uint32_t
 216 gbm_bo_get_format(struct gbm_bo *bo)
 217 {
 218    return bo->format;
 219 }
 220
 221 /** Get the handle of the buffer object
 222  *
 223  * This is stored in the platform generic union gbm_bo_handle type. However
 224  * the format of this handle is platform specific.
 225  *
 226  * \param bo The buffer object
 227  * \return Returns the handle of the allocated buffer object
 228  */
 229 GBM_EXPORT union gbm_bo_handle
 230 gbm_bo_get_handle(struct gbm_bo *bo)
 231 {
 232    return bo->handle;
 233 }
 234
 235 /** Get a DMA-BUF file descriptor for the buffer object
 236  *
 237  * This function creates a DMA-BUF (also known as PRIME) file descriptor
 238  * handle for the buffer object.  Eeach call to gbm_bo_get_fd() returns a new
 239  * file descriptor and the caller is responsible for closing the file
 240  * descriptor.
 241
 242  * \param bo The buffer object
 243  * \return Returns a file descriptor referring  to the underlying buffer
 244  */
 245 GBM_EXPORT int
 246 gbm_bo_get_fd(struct gbm_bo *bo)
 247 {
 248    return bo->gbm->bo_get_fd(bo);
 249 }
 250
 251
 252 /** Write data into the buffer object
 253  *
 254  * If the buffer object was created with the GBM_BO_USE_WRITE flag,
 255  * this function can used to write data into the buffer object.  The
 256  * data is copied directly into the object and it's the responsiblity
 257  * of the caller to make sure the data represents valid pixel data,
 258  * according to the width, height, stride and format of the buffer object.
 259  *
 260  * \param bo The buffer object
 261  * \param buf The data to write
 262  * \param count The number of bytes to write
 263  * \return Returns 0 on success, otherwise -1 is returned an errno set
 264  */
 265 GBM_EXPORT int
 266 gbm_bo_write(struct gbm_bo *bo, const void *buf, size_t count)
 267 {
 268    return bo->gbm->bo_write(bo, buf, count);
 269 }
 270
 271 /** Get the gbm device used to create the buffer object
 272  *
 273  * \param bo The buffer object
 274  * \return Returns the gbm device with which the buffer object was created
 275  */
 276 GBM_EXPORT struct gbm_device *
 277 gbm_bo_get_device(struct gbm_bo *bo)
 278 {
 279         return bo->gbm;
 280 }
 281
 282 /** Set the user data associated with a buffer object
 283  *
 284  * \param bo The buffer object
 285  * \param data The data to associate to the buffer object
 286  * \param destroy_user_data A callback (which may be %NULL) that will be
 287  * called prior to the buffer destruction
 288  */
 289 GBM_EXPORT void
 290 gbm_bo_set_user_data(struct gbm_bo *bo, void *data,
 291                      void (*destroy_user_data)(struct gbm_bo *, void *))
 292 {
 293    bo->user_data = data;
 294    bo->destroy_user_data = destroy_user_data;
 295 }
 296
 297 /** Get the user data associated with a buffer object
 298  *
 299  * \param bo The buffer object
 300  * \return Returns the user data associated with the buffer object or %NULL
 301  * if no data was associated with it
 302  *
 303  * \sa gbm_bo_set_user_data()
 304  */
 305 GBM_EXPORT void *
 306 gbm_bo_get_user_data(struct gbm_bo *bo)
 307 {
 308    return bo->user_data;
 309 }
 310
 311 /**
 312  * Destroys the given buffer object and frees all resources associated with
 313  * it.
 314  *
 315  * \param bo The buffer object
 316  */
 317 GBM_EXPORT void
 318 gbm_bo_destroy(struct gbm_bo *bo)
 319 {
 320    if (bo->destroy_user_data)
 321       bo->destroy_user_data(bo, bo->user_data);
 322
 323    bo->gbm->bo_destroy(bo);
 324 }
 325
 326 /**
 327  * Allocate a buffer object for the given dimensions
 328  *
 329  * \param gbm The gbm device returned from gbm_create_device()
 330  * \param width The width for the buffer
 331  * \param height The height for the buffer
 332  * \param format The format to use for the buffer
 333  * \param usage The union of the usage flags for this buffer
 334  *
 335  * \return A newly allocated buffer that should be freed with gbm_bo_destroy()
 336  * when no longer needed. If an error occurs during allocation %NULL will be
 337  * returned and errno set.
 338  *
 339  * \sa enum gbm_bo_format for the list of formats
 340  * \sa enum gbm_bo_flags for the list of usage flags
 341  */
 342 GBM_EXPORT struct gbm_bo *
 343 gbm_bo_create(struct gbm_device *gbm,
 344               uint32_t width, uint32_t height,
 345               uint32_t format, uint32_t usage)
 346 {
 347    if (width == 0 || height == 0) {
 348       errno = EINVAL;
 349       return NULL;
 350    }
 351
 352    return gbm->bo_create(gbm, width, height, format, usage);
 353 }
 354
 355 /**
 356  * Create a gbm buffer object from an foreign object
 357  *
 358  * This function imports a foreign object and creates a new gbm bo for it.
 359  * This enabled using the foreign object with a display API such as KMS.
 360  * Currently two types of foreign objects are supported, indicated by the type
 361  * argument:
 362  *
 363  *   GBM_BO_IMPORT_WL_BUFFER
 364  *   GBM_BO_IMPORT_EGL_IMAGE
 365  *   GBM_BO_IMPORT_FD
 366  *
 367  * The the gbm bo shares the underlying pixels but its life-time is
 368  * independent of the foreign object.
 369  *
 370  * \param gbm The gbm device returned from gbm_create_device()
 371  * \param gbm The type of object we're importing
 372  * \param gbm Pointer to the external object
 373  * \param usage The union of the usage flags for this buffer
 374  *
 375  * \return A newly allocated buffer object that should be freed with
 376  * gbm_bo_destroy() when no longer needed. On error, %NULL is returned
 377  * and errno is set.
 378  *
 379  * \sa enum gbm_bo_flags for the list of usage flags
 380  */
 381 GBM_EXPORT struct gbm_bo *
 382 gbm_bo_import(struct gbm_device *gbm,
 383               uint32_t type, void *buffer, uint32_t usage)
 384 {
 385    return gbm->bo_import(gbm, type, buffer, usage);
 386 }
 387
 388 /**
 389  * Map a region of a gbm buffer object for cpu access
 390  *
 391  * This function maps a region of a gbm bo for cpu read and/or write
 392  * access.
 393  *
 394  * \param bo The buffer object
 395  * \param x The X (top left origin) starting position of the mapped region for
 396  * the buffer
 397  * \param y The Y (top left origin) starting position of the mapped region for
 398  * the buffer
 399  * \param width The width of the mapped region for the buffer
 400  * \param height The height of the mapped region for the buffer
 401  * \param flags The union of the GBM_BO_TRANSFER_* flags for this buffer
 402  * \param stride Ptr for returned stride in bytes of the mapped region
 403  * \param map_data Returned opaque ptr for the mapped region
 404  *
 405  * \return Address of the mapped buffer that should be unmapped with
 406  * gbm_bo_unmap() when no longer needed. On error, %NULL is returned
 407  * and errno is set.
 408  *
 409  * \sa enum gbm_bo_transfer_flags for the list of flags
 410  */
 411 GBM_EXPORT void *
 412 gbm_bo_map(struct gbm_bo *bo,
 413               uint32_t x, uint32_t y,
 414               uint32_t width, uint32_t height,
 415               uint32_t flags, uint32_t *stride, void **map_data)
 416 {
 417    if (!bo || width == 0 || height == 0 || !stride || !map_data) {
 418       errno = EINVAL;
 419       return NULL;
 420    }
 421
 422    return bo->gbm->bo_map(bo, x, y, width, height,
 423                           flags, stride, map_data);
 424 }
 425
 426 /**
 427  * Unmap a previously mapped region of a gbm buffer object
 428  *
 429  * This function unmaps a region of a gbm bo for cpu read and/or write
 430  * access.
 431  *
 432  * \param bo The buffer object
 433  * \param map_data opaque ptr returned from prior gbm_bo_map
 434  */
 435 GBM_EXPORT void
 436 gbm_bo_unmap(struct gbm_bo *bo, void *map_data)
 437 {
 438    bo->gbm->bo_unmap(bo, map_data);
 439 }
 440
 441 /**
 442  * Allocate a surface object
 443  *
 444  * \param gbm The gbm device returned from gbm_create_device()
 445  * \param width The width for the surface
 446  * \param height The height for the surface
 447  * \param format The format to use for the surface
 448  *
 449  * \return A newly allocated surface that should be freed with
 450  * gbm_surface_destroy() when no longer needed. If an error occurs
 451  * during allocation %NULL will be returned.
 452  *
 453  * \sa enum gbm_bo_format for the list of formats
 454  */
 455 GBM_EXPORT struct gbm_surface *
 456 gbm_surface_create(struct gbm_device *gbm,
 457                    uint32_t width, uint32_t height,
 458                    uint32_t format, uint32_t flags)
 459 {
 460    return gbm->surface_create(gbm, width, height, format, flags);
 461 }
 462
 463 /**
 464  * Destroys the given surface and frees all resources associated with
 465  * it.
 466  *
 467  * All buffers locked with gbm_surface_lock_front_buffer() should be
 468  * released prior to calling this function.
 469  *
 470  * \param surf The surface
 471  */
 472 GBM_EXPORT void
 473 gbm_surface_destroy(struct gbm_surface *surf)
 474 {
 475    surf->gbm->surface_destroy(surf);
 476 }
 477
 478 /**
 479  * Lock the surface's current front buffer
 480  *
 481  * Lock rendering to the surface's current front buffer until it is
 482  * released with gbm_surface_release_buffer().
 483  *
 484  * This function must be called exactly once after calling
 485  * eglSwapBuffers.  Calling it before any eglSwapBuffer has happened
 486  * on the surface or two or more times after eglSwapBuffers is an
 487  * error.  A new bo representing the new front buffer is returned.  On
 488  * multiple invocations, all the returned bos must be released in
 489  * order to release the actual surface buffer.
 490  *
 491  * \param surf The surface
 492  *
 493  * \return A buffer object that should be released with
 494  * gbm_surface_release_buffer() when no longer needed.  The implementation
 495  * is free to reuse buffers released with gbm_surface_release_buffer() so
 496  * this bo should not be destroyed using gbm_bo_destroy().  If an error
 497  * occurs this function returns %NULL.
 498  */
 499 GBM_EXPORT struct gbm_bo *
 500 gbm_surface_lock_front_buffer(struct gbm_surface *surf)
 501 {
 502    return surf->gbm->surface_lock_front_buffer(surf);
 503 }
 504
 505 /**
 506  * Release a locked buffer obtained with gbm_surface_lock_front_buffer()
 507  *
 508  * Returns the underlying buffer to the gbm surface.  Releasing a bo
 509  * will typically make gbm_surface_has_free_buffer() return 1 and thus
 510  * allow rendering the next frame, but not always. The implementation
 511  * may choose to destroy the bo immediately or reuse it, in which case
 512  * the user data associated with it is unchanged.
 513  *
 514  * \param surf The surface
 515  * \param bo The buffer object
 516  */
 517 GBM_EXPORT void
 518 gbm_surface_release_buffer(struct gbm_surface *surf, struct gbm_bo *bo)
 519 {
 520    surf->gbm->surface_release_buffer(surf, bo);
 521 }
 522
 523 /**
 524  * Return whether or not a surface has free (non-locked) buffers
 525  *
 526  * Before starting a new frame, the surface must have a buffer
 527  * available for rendering.  Initially, a gbm surface will have a free
 528  * buffer, but after one of more buffers have been locked (\sa
 529  * gbm_surface_lock_front_buffer()), the application must check for a
 530  * free buffer before rendering.
 531  *
 532  * If a surface doesn't have a free buffer, the application must
 533  * return a buffer to the surface using gbm_surface_release_buffer()
 534  * and after that, the application can query for free buffers again.
 535  *
 536  * \param surf The surface
 537  * \return 1 if the surface has free buffers, 0 otherwise
 538  */
 539 GBM_EXPORT int
 540 gbm_surface_has_free_buffers(struct gbm_surface *surf)
 541 {
 542    return surf->gbm->surface_has_free_buffers(surf);
 543 }