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
  30 #include <stddef.h>
  31 #include <stdio.h>
  32 #include <stdlib.h>
  33 #include <string.h>
  34 #include <stdint.h>
  35
  36 #include <sys/types.h>
  37 #include <sys/stat.h>
  38 #include <unistd.h>
  39
  40 #include "gbm.h"
  41 #include "gbmint.h"
  42 #include "backend.h"
  43
  44 #define ARRAY_SIZE(a) (sizeof(a)/sizeof((a)[0]))
  45
  46 struct gbm_device *devices[16];
  47
  48 static int device_num = 0;
  49
  50 /** Returns the file description for the gbm device
  51  *
  52  * \return The fd that the struct gbm_device was created with
  53  */
  54 GBM_EXPORT int
  55 gbm_device_get_fd(struct gbm_device *gbm)
  56 {
  57    return gbm->fd;
  58 }
  59
  60 /* FIXME: maybe superfluous, use udev subclass from the fd? */
  61 /** Get the backend name for the given gbm device
  62  *
  63  * \return The backend name string - this belongs to the device and must not
  64  * be freed
  65  */
  66 GBM_EXPORT const char *
  67 gbm_device_get_backend_name(struct gbm_device *gbm)
  68 {
  69    return gbm->name;
  70 }
  71
  72 /** Test if a format is supported for a given set of usage flags.
  73  *
  74  * \param gbm The created buffer manager
  75  * \param format The format to test
  76  * \param usage A bitmask of the usages to test the format against
  77  * \return 1 if the format is supported otherwise 0
  78  *
  79  * \sa enum gbm_bo_flags for the list of flags that the format can be
  80  * tested against
  81  *
  82  * \sa enum gbm_bo_format for the list of formats
  83  */
  84 int
  85 gbm_device_is_format_supported(struct gbm_device *gbm,
  86                                uint32_t format, uint32_t usage)
  87 {
  88    return gbm->is_format_supported(gbm, format, usage);
  89 }
  90
  91 /** Destroy the gbm device and free all resources associated with it.
  92  *
  93  * \param gbm The device created using gbm_create_device()
  94  */
  95 GBM_EXPORT void
  96 gbm_device_destroy(struct gbm_device *gbm)
  97 {
  98    gbm->refcount--;
  99    if (gbm->refcount == 0)
 100       gbm->destroy(gbm);
 101 }
 102
 103 GBM_EXPORT struct gbm_device *
 104 _gbm_mesa_get_device(int fd)
 105 {
 106    struct gbm_device *gbm = NULL;
 107    struct stat buf;
 108    dev_t dev;
 109    int i;
 110
 111    if (fd < 0 || fstat(fd, &buf) < 0 || !S_ISCHR(buf.st_mode)) {
 112       fprintf(stderr, "_gbm_mesa_get_device: invalid fd: %d\n", fd);
 113       return NULL;
 114    }
 115
 116    for (i = 0; i < device_num; ++i) {
 117       dev = devices[i]->stat.st_rdev;
 118       if (major(dev) == major(buf.st_rdev) &&
 119           minor(dev) == minor(buf.st_rdev)) {
 120          gbm = devices[i];
 121          gbm->refcount++;
 122          break;
 123       }
 124    }
 125
 126    return gbm;
 127 }
 128
 129 /** Create a gbm device for allocating buffers
 130  *
 131  * The file descriptor passed in is used by the backend to communicate with
 132  * platform for allocating the memory. For allocations using DRI this would be
 133  * the file descriptor returned when opening a device such as \c
 134  * /dev/dri/card0
 135  *
 136  * \param fd The file descriptor for an backend specific device
 137  * \return The newly created struct gbm_device. The resources associated with
 138  * the device should be freed with gbm_device_destroy() when it is no longer
 139  * needed. If the creation of the device failed NULL will be returned.
 140  */
 141 GBM_EXPORT struct gbm_device *
 142 gbm_create_device(int fd)
 143 {
 144    struct gbm_device *gbm = NULL;
 145    struct stat buf;
 146
 147    if (fd < 0 || fstat(fd, &buf) < 0 || !S_ISCHR(buf.st_mode)) {
 148       fprintf(stderr, "gbm_create_device: invalid fd: %d\n", fd);
 149       return NULL;
 150    }
 151
 152    if (device_num == 0)
 153       memset(devices, 0, sizeof devices);
 154
 155    gbm = _gbm_create_device(fd);
 156    if (gbm == NULL)
 157       return NULL;
 158
 159    gbm->dummy = gbm_create_device;
 160    gbm->stat = buf;
 161    gbm->refcount = 1;
 162
 163    if (device_num < ARRAY_SIZE(devices)-1)
 164       devices[device_num++] = gbm;
 165
 166    return gbm;
 167 }
 168
 169 /** Get the width of the buffer object
 170  *
 171  * \param bo The buffer object
 172  * \return The width of the allocated buffer object
 173  *
 174  */
 175 GBM_EXPORT unsigned int
 176 gbm_bo_get_width(struct gbm_bo *bo)
 177 {
 178    return bo->width;
 179 }
 180
 181 /** Get the height of the buffer object
 182  *
 183  * \param bo The buffer object
 184  * \return The height of the allocated buffer object
 185  */
 186 GBM_EXPORT unsigned int
 187 gbm_bo_get_height(struct gbm_bo *bo)
 188 {
 189    return bo->height;
 190 }
 191
 192 /** Get the stride of the buffer object
 193  *
 194  * This is calculated by the backend when it does the allocation in
 195  * gbm_bo_create()
 196  *
 197  * \param bo The buffer object
 198  * \return The stride of the allocated buffer object in bytes
 199  */
 200 GBM_EXPORT uint32_t
 201 gbm_bo_get_stride(struct gbm_bo *bo)
 202 {
 203    return bo->stride;
 204 }
 205
 206 /** Get the format of the buffer object
 207  *
 208  * The format of the pixels in the buffer.
 209  *
 210  * \param bo The buffer object
 211  * \return The format of buffer object, on of the GBM_FORMAT_* codes
 212  */
 213 GBM_EXPORT uint32_t
 214 gbm_bo_get_format(struct gbm_bo *bo)
 215 {
 216    return bo->format;
 217 }
 218
 219 /** Get the handle of the buffer object
 220  *
 221  * This is stored in the platform generic union gbm_bo_handle type. However
 222  * the format of this handle is platform specific.
 223  *
 224  * \param bo The buffer object
 225  * \return Returns the handle of the allocated buffer object
 226  */
 227 GBM_EXPORT union gbm_bo_handle
 228 gbm_bo_get_handle(struct gbm_bo *bo)
 229 {
 230    return bo->handle;
 231 }
 232
 233 /** Write data into the buffer object
 234  *
 235  * If the buffer object was created with the GBM_BO_USE_WRITE flag,
 236  * this function can used to write data into the buffer object.  The
 237  * data is copied directly into the object and it's the responsiblity
 238  * of the caller to make sure the data represents valid pixel data,
 239  * according to the width, height, stride and format of the buffer object.
 240  *
 241  * \param bo The buffer object
 242  * \param buf The data to write
 243  * \param count The number of bytes to write
 244  * \return Returns -1 on error, 0 otherwise
 245  */
 246 GBM_EXPORT int
 247 gbm_bo_write(struct gbm_bo *bo, const void *buf, size_t count)
 248 {
 249    return bo->gbm->bo_write(bo, buf, count);
 250 }
 251
 252 /** Get the gbm device used to create the buffer object
 253  *
 254  * \param bo The buffer object
 255  * \return Returns the gbm device with which the buffer object was created
 256  */
 257 GBM_EXPORT struct gbm_device *
 258 gbm_bo_get_device(struct gbm_bo *bo)
 259 {
 260         return bo->gbm;
 261 }
 262
 263 /** Set the user data associated with a buffer object
 264  *
 265  * \param bo The buffer object
 266  * \param data The data to associate to the buffer object
 267  * \param destroy_user_data A callback (which may be %NULL) that will be
 268  * called prior to the buffer destruction
 269  */
 270 GBM_EXPORT void
 271 gbm_bo_set_user_data(struct gbm_bo *bo, void *data,
 272                      void (*destroy_user_data)(struct gbm_bo *, void *))
 273 {
 274    bo->user_data = data;
 275    bo->destroy_user_data = destroy_user_data;
 276 }
 277
 278 /** Get the user data associated with a buffer object
 279  *
 280  * \param bo The buffer object
 281  * \return Returns the user data associated with the buffer object or %NULL
 282  * if no data was associated with it
 283  *
 284  * \sa gbm_bo_set_user_data()
 285  */
 286 GBM_EXPORT void *
 287 gbm_bo_get_user_data(struct gbm_bo *bo)
 288 {
 289    return bo->user_data;
 290 }
 291
 292 /**
 293  * Destroys the given buffer object and frees all resources associated with
 294  * it.
 295  *
 296  * \param bo The buffer object
 297  */
 298 GBM_EXPORT void
 299 gbm_bo_destroy(struct gbm_bo *bo)
 300 {
 301    if (bo->destroy_user_data)
 302       bo->destroy_user_data(bo, bo->user_data);
 303
 304    bo->gbm->bo_destroy(bo);
 305 }
 306
 307 /**
 308  * Allocate a buffer object for the given dimensions
 309  *
 310  * \param gbm The gbm device returned from gbm_create_device()
 311  * \param width The width for the buffer
 312  * \param height The height for the buffer
 313  * \param format The format to use for the buffer
 314  * \param usage The union of the usage flags for this buffer
 315  *
 316  * \return A newly allocated buffer that should be freed with gbm_bo_destroy()
 317  * when no longer needed. If an error occurs during allocation %NULL will be
 318  * returned.
 319  *
 320  * \sa enum gbm_bo_format for the list of formats
 321  * \sa enum gbm_bo_flags for the list of usage flags
 322  */
 323 GBM_EXPORT struct gbm_bo *
 324 gbm_bo_create(struct gbm_device *gbm,
 325               uint32_t width, uint32_t height,
 326               uint32_t format, uint32_t usage)
 327 {
 328    if (width == 0 || height == 0)
 329       return NULL;
 330
 331    if (usage & GBM_BO_USE_CURSOR_64X64 &&
 332        (width != 64 || height != 64))
 333       return NULL;
 334
 335    return gbm->bo_create(gbm, width, height, format, usage);
 336 }
 337
 338 /**
 339  * Create a gbm buffer object from an foreign object
 340  *
 341  * This function imports a foreign object and creates a new gbm bo for it.
 342  * This enabled using the foreign object with a display API such as KMS.
 343  * Currently two types of foreign objects are supported, indicated by the type
 344  * argument:
 345  *
 346  *   GBM_BO_IMPORT_WL_BUFFER
 347  *   GBM_BO_IMPORT_EGL_IMAGE
 348  *
 349  * The the gbm bo shares the underlying pixels but its life-time is
 350  * independent of the foreign object.
 351  *
 352  * \param gbm The gbm device returned from gbm_create_device()
 353  * \param gbm The type of object we're importing
 354  * \param gbm Pointer to the external object
 355  * \param usage The union of the usage flags for this buffer
 356  *
 357  * \return A newly allocated buffer object that should be freed with
 358  * gbm_bo_destroy() when no longer needed.
 359  *
 360  * \sa enum gbm_bo_flags for the list of usage flags
 361  */
 362 GBM_EXPORT struct gbm_bo *
 363 gbm_bo_import(struct gbm_device *gbm,
 364               uint32_t type, void *buffer, uint32_t usage)
 365 {
 366    return gbm->bo_import(gbm, type, buffer, usage);
 367 }
 368
 369 /**
 370  * Allocate a surface object
 371  *
 372  * \param gbm The gbm device returned from gbm_create_device()
 373  * \param width The width for the surface
 374  * \param height The height for the surface
 375  * \param format The format to use for the surface
 376  *
 377  * \return A newly allocated surface that should be freed with
 378  * gbm_surface_destroy() when no longer needed. If an error occurs
 379  * during allocation %NULL will be returned.
 380  *
 381  * \sa enum gbm_bo_format for the list of formats
 382  */
 383 GBM_EXPORT struct gbm_surface *
 384 gbm_surface_create(struct gbm_device *gbm,
 385                    uint32_t width, uint32_t height,
 386                    uint32_t format, uint32_t flags)
 387 {
 388    return gbm->surface_create(gbm, width, height, format, flags);
 389 }
 390
 391 /**
 392  * Destroys the given surface and frees all resources associated with
 393  * it.
 394  *
 395  * All buffers locked with gbm_surface_lock_front_buffer() should be
 396  * released prior to calling this function.
 397  *
 398  * \param surf The surface
 399  */
 400 GBM_EXPORT void
 401 gbm_surface_destroy(struct gbm_surface *surf)
 402 {
 403    surf->gbm->surface_destroy(surf);
 404 }
 405
 406 /**
 407  * Lock the surface's current front buffer
 408  *
 409  * Lock rendering to the surface's current front buffer until it is
 410  * released with gbm_surface_release_buffer().
 411  *
 412  * This function must be called exactly once after calling
 413  * eglSwapBuffers.  Calling it before any eglSwapBuffer has happened
 414  * on the surface or two or more times after eglSwapBuffers is an
 415  * error.  A new bo representing the new front buffer is returned.  On
 416  * multiple invocations, all the returned bos must be released in
 417  * order to release the actual surface buffer.
 418  *
 419  * \param surf The surface
 420  *
 421  * \return A buffer object that should be released with
 422  * gbm_surface_release_buffer() when no longer needed.  The implementation
 423  * is free to reuse buffers released with gbm_surface_release_buffer() so
 424  * this bo should not be destroyed using gbm_bo_destroy().  If an error
 425  * occurs this function returns %NULL.
 426  */
 427 GBM_EXPORT struct gbm_bo *
 428 gbm_surface_lock_front_buffer(struct gbm_surface *surf)
 429 {
 430    return surf->gbm->surface_lock_front_buffer(surf);
 431 }
 432
 433 /**
 434  * Release a locked buffer obtained with gbm_surface_lock_front_buffer()
 435  *
 436  * Returns the underlying buffer to the gbm surface.  Releasing a bo
 437  * will typically make gbm_surface_has_free_buffer() return 1 and thus
 438  * allow rendering the next frame, but not always. The implementation
 439  * may choose to destroy the bo immediately or reuse it, in which case
 440  * the user data associated with it is unchanged.
 441  *
 442  * \param surf The surface
 443  * \param bo The buffer object
 444  */
 445 GBM_EXPORT void
 446 gbm_surface_release_buffer(struct gbm_surface *surf, struct gbm_bo *bo)
 447 {
 448    surf->gbm->surface_release_buffer(surf, bo);
 449 }
 450
 451 /**
 452  * Return whether or not a surface has free (non-locked) buffers
 453  *
 454  * Before starting a new frame, the surface must have a buffer
 455  * available for rendering.  Initially, a gbm surface will have a free
 456  * buffer, but after one of more buffers have been locked (\sa
 457  * gbm_surface_lock_front_buffer()), the application must check for a
 458  * free buffer before rendering.
 459  *
 460  * If a surface doesn't have a free buffer, the application must
 461  * return a buffer to the surface using gbm_surface_release_buffer()
 462  * and after that, the application can query for free buffers again.
 463  *
 464  * \param surf The surface
 465  * \return 1 if the surface has free buffers, 0 otherwise
 466  */
 467 GBM_EXPORT int
 468 gbm_surface_has_free_buffers(struct gbm_surface *surf)
 469 {
 470    return surf->gbm->surface_has_free_buffers(surf);
 471 }