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