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