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