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 "common.h"
  43 #include "backend.h"
  44
  45 #define ARRAY_SIZE(a) (sizeof(a)/sizeof((a)[0]))
  46
  47 struct gbm_device *devices[16];
  48
  49 static int device_num = 0;
  50
  51 /** Returns the file description for the gbm device
  52  *
  53  * \return The fd that the struct gbm_device was created with
  54  */
  55 GBM_EXPORT int
  56 gbm_device_get_fd(struct gbm_device *gbm)
  57 {
  58    return gbm->fd;
  59 }
  60
  61 /* FIXME: maybe superfluous, use udev subclass from the fd? */
  62 /** Get the backend name for the given gbm device
  63  *
  64  * \return The backend name string - this belongs to the device and must not
  65  * be freed
  66  */
  67 GBM_EXPORT const char *
  68 gbm_device_get_backend_name(struct gbm_device *gbm)
  69 {
  70    return gbm->name;
  71 }
  72
  73 /** Test if a format is supported for a given set of usage flags.
  74  *
  75  * \param gbm The created buffer manager
  76  * \param format The format to test
  77  * \param usage A bitmask of the usages to test the format against
  78  * \return 1 if the format is supported otherwise 0
  79  *
  80  * \sa enum gbm_bo_flags for the list of flags that the format can be
  81  * tested against
  82  *
  83  * \sa enum gbm_bo_format for the list of formats
  84  */
  85 int
  86 gbm_device_is_format_supported(struct gbm_device *gbm,
  87                                uint32_t format, uint32_t usage)
  88 {
  89    return gbm->is_format_supported(gbm, format, usage);
  90 }
  91
  92 /** Destroy the gbm device and free all resources associated with it.
  93  *
  94  * \param gbm The device created using gbm_create_device()
  95  */
  96 GBM_EXPORT void
  97 gbm_device_destroy(struct gbm_device *gbm)
  98 {
  99    gbm->refcount--;
 100    if (gbm->refcount == 0)
 101       gbm->destroy(gbm);
 102 }
 103
 104 GBM_EXPORT struct gbm_device *
 105 _gbm_mesa_get_device(int fd)
 106 {
 107    struct gbm_device *gbm = NULL;
 108    struct stat buf;
 109    dev_t dev;
 110    int i;
 111
 112    if (fd < 0 || fstat(fd, &buf) < 0 || !S_ISCHR(buf.st_mode)) {
 113       fprintf(stderr, "_gbm_mesa_get_device: invalid fd: %d\n", fd);
 114       return NULL;
 115    }
 116
 117    for (i = 0; i < device_num; ++i) {
 118       dev = devices[i]->stat.st_rdev;
 119       if (major(dev) == major(buf.st_rdev) &&
 120           minor(dev) == minor(buf.st_rdev)) {
 121          gbm = devices[i];
 122          gbm->refcount++;
 123          break;
 124       }
 125    }
 126
 127    return gbm;
 128 }
 129
 130 /** Create a gbm device for allocating buffers
 131  *
 132  * The file descriptor passed in is used by the backend to communicate with
 133  * platform for allocating the memory. For allocations using DRI this would be
 134  * the file descriptor returned when opening a device such as \c
 135  * /dev/dri/card0
 136  *
 137  * \param fd The file descriptor for an backend specific device
 138  * \return The newly created struct gbm_device. The resources associated with
 139  * the device should be freed with gbm_device_destroy() when it is no longer
 140  * needed. If the creation of the device failed NULL will be returned.
 141  */
 142 GBM_EXPORT struct gbm_device *
 143 gbm_create_device(int fd)
 144 {
 145    struct gbm_device *gbm = NULL;
 146    struct stat buf;
 147
 148    if (fd < 0 || fstat(fd, &buf) < 0 || !S_ISCHR(buf.st_mode)) {
 149       fprintf(stderr, "gbm_create_device: invalid fd: %d\n", fd);
 150       return NULL;
 151    }
 152
 153    if (device_num == 0)
 154       memset(devices, 0, sizeof devices);
 155
 156    gbm = _gbm_create_device(fd);
 157    if (gbm == NULL)
 158       return NULL;
 159
 160    gbm->dummy = gbm_create_device;
 161    gbm->stat = buf;
 162    gbm->refcount = 1;
 163
 164    if (device_num < ARRAY_SIZE(devices)-1)
 165       devices[device_num++] = gbm;
 166
 167    return gbm;
 168 }
 169
 170 /** Get the width of the buffer object
 171  *
 172  * \param bo The buffer object
 173  * \return The width of the allocated buffer object
 174  *
 175  */
 176 GBM_EXPORT unsigned int
 177 gbm_bo_get_width(struct gbm_bo *bo)
 178 {
 179    return bo->width;
 180 }
 181
 182 /** Get the height of the buffer object
 183  *
 184  * \param bo The buffer object
 185  * \return The height of the allocated buffer object
 186  */
 187 GBM_EXPORT unsigned int
 188 gbm_bo_get_height(struct gbm_bo *bo)
 189 {
 190    return bo->height;
 191 }
 192
 193 /** Get the stride of the buffer object
 194  *
 195  * This is calculated by the backend when it does the allocation in
 196  * gbm_bo_create()
 197  *
 198  * \param bo The buffer object
 199  * \return The stride of the allocated buffer object in bytes
 200  */
 201 GBM_EXPORT uint32_t
 202 gbm_bo_get_stride(struct gbm_bo *bo)
 203 {
 204    return bo->stride;
 205 }
 206
 207 /** Get the format of the buffer object
 208  *
 209  * The format of the pixels in the buffer.
 210  *
 211  * \param bo The buffer object
 212  * \return The format of buffer object, on of the GBM_FORMAT_* codes
 213  */
 214 GBM_EXPORT uint32_t
 215 gbm_bo_get_format(struct gbm_bo *bo)
 216 {
 217    return bo->format;
 218 }
 219
 220 /** Get the handle of the buffer object
 221  *
 222  * This is stored in the platform generic union gbm_bo_handle type. However
 223  * the format of this handle is platform specific.
 224  *
 225  * \param bo The buffer object
 226  * \return Returns the handle of the allocated buffer object
 227  */
 228 GBM_EXPORT union gbm_bo_handle
 229 gbm_bo_get_handle(struct gbm_bo *bo)
 230 {
 231    return bo->handle;
 232 }
 233
 234 /** Write data into the buffer object
 235  *
 236  * If the buffer object was created with the GBM_BO_USE_WRITE flag,
 237  * this function can used to write data into the buffer object.  The
 238  * data is copied directly into the object and it's the responsiblity
 239  * of the caller to make sure the data represents valid pixel data,
 240  * according to the width, height, stride and format of the buffer object.
 241  *
 242  * \param bo The buffer object
 243  * \param buf The data to write
 244  * \param count The number of bytes to write
 245  * \return Returns -1 on error, 0 otherwise
 246  */
 247 GBM_EXPORT int
 248 gbm_bo_write(struct gbm_bo *bo, const void *buf, size_t count)
 249 {
 250    return bo->gbm->bo_write(bo, buf, count);
 251 }
 252
 253 /** Get the gbm device used to create the buffer object
 254  *
 255  * \param bo The buffer object
 256  * \return Returns the gbm device with which the buffer object was created
 257  */
 258 GBM_EXPORT struct gbm_device *
 259 gbm_bo_get_device(struct gbm_bo *bo)
 260 {
 261         return bo->gbm;
 262 }
 263
 264 /** Set the user data associated with a buffer object
 265  *
 266  * \param bo The buffer object
 267  * \param data The data to associate to the buffer object
 268  * \param destroy_user_data A callback (which may be %NULL) that will be
 269  * called prior to the buffer destruction
 270  */
 271 GBM_EXPORT void
 272 gbm_bo_set_user_data(struct gbm_bo *bo, void *data,
 273                      void (*destroy_user_data)(struct gbm_bo *, void *))
 274 {
 275    bo->user_data = data;
 276    bo->destroy_user_data = destroy_user_data;
 277 }
 278
 279 /** Get the user data associated with a buffer object
 280  *
 281  * \param bo The buffer object
 282  * \return Returns the user data associated with the buffer object or %NULL
 283  * if no data was associated with it
 284  *
 285  * \sa gbm_bo_set_user_data()
 286  */
 287 GBM_EXPORT void *
 288 gbm_bo_get_user_data(struct gbm_bo *bo)
 289 {
 290    return bo->user_data;
 291 }
 292
 293 /**
 294  * Destroys the given buffer object and frees all resources associated with
 295  * it.
 296  *
 297  * \param bo The buffer object
 298  */
 299 GBM_EXPORT void
 300 gbm_bo_destroy(struct gbm_bo *bo)
 301 {
 302    if (bo->destroy_user_data)
 303       bo->destroy_user_data(bo, bo->user_data);
 304
 305    bo->gbm->bo_destroy(bo);
 306 }
 307
 308 /**
 309  * Allocate a buffer object for the given dimensions
 310  *
 311  * \param gbm The gbm device returned from gbm_create_device()
 312  * \param width The width for the buffer
 313  * \param height The height for the buffer
 314  * \param format The format to use for the buffer
 315  * \param usage The union of the usage flags for this buffer
 316  *
 317  * \return A newly allocated buffer that should be freed with gbm_bo_destroy()
 318  * when no longer needed. If an error occurs during allocation %NULL will be
 319  * returned.
 320  *
 321  * \sa enum gbm_bo_format for the list of formats
 322  * \sa enum gbm_bo_flags for the list of usage flags
 323  */
 324 GBM_EXPORT struct gbm_bo *
 325 gbm_bo_create(struct gbm_device *gbm,
 326               uint32_t width, uint32_t height,
 327               uint32_t format, uint32_t usage)
 328 {
 329    if (width == 0 || height == 0)
 330       return NULL;
 331
 332    if (usage & GBM_BO_USE_CURSOR_64X64 &&
 333        (width != 64 || height != 64))
 334       return NULL;
 335
 336    return gbm->bo_create(gbm, width, height, format, usage);
 337 }
 338
 339 /**
 340  * Create a gbm buffer object from an foreign object
 341  *
 342  * This function imports a foreign object and creates a new gbm bo for it.
 343  * This enabled using the foreign object with a display API such as KMS.
 344  * Currently two types of foreign objects are supported, indicated by the type
 345  * argument:
 346  *
 347  *   GBM_BO_IMPORT_WL_BUFFER
 348  *   GBM_BO_IMPORT_EGL_IMAGE
 349  *
 350  * The the gbm bo shares the underlying pixels but its life-time is
 351  * independent of the foreign object.
 352  *
 353  * \param gbm The gbm device returned from gbm_create_device()
 354  * \param gbm The type of object we're importing
 355  * \param gbm Pointer to the external object
 356  * \param usage The union of the usage flags for this buffer
 357  *
 358  * \return A newly allocated buffer object that should be freed with
 359  * gbm_bo_destroy() when no longer needed.
 360  *
 361  * \sa enum gbm_bo_flags for the list of usage flags
 362  */
 363 GBM_EXPORT struct gbm_bo *
 364 gbm_bo_import(struct gbm_device *gbm,
 365               uint32_t type, void *buffer, uint32_t usage)
 366 {
 367    return gbm->bo_import(gbm, type, buffer, usage);
 368 }
 369
 370 /**
 371  * Allocate a surface object
 372  *
 373  * \param gbm The gbm device returned from gbm_create_device()
 374  * \param width The width for the surface
 375  * \param height The height for the surface
 376  * \param format The format to use for the surface
 377  *
 378  * \return A newly allocated surface that should be freed with
 379  * gbm_surface_destroy() when no longer needed. If an error occurs
 380  * during allocation %NULL will be returned.
 381  *
 382  * \sa enum gbm_bo_format for the list of formats
 383  */
 384 GBM_EXPORT struct gbm_surface *
 385 gbm_surface_create(struct gbm_device *gbm,
 386                    uint32_t width, uint32_t height,
 387                    uint32_t format, uint32_t flags)
 388 {
 389    return gbm->surface_create(gbm, width, height, format, flags);
 390 }
 391
 392 /**
 393  * Destroys the given surface and frees all resources associated with
 394  * it.
 395  *
 396  * All buffers locked with gbm_surface_lock_front_buffer() should be
 397  * released prior to calling this function.
 398  *
 399  * \param surf The surface
 400  */
 401 GBM_EXPORT void
 402 gbm_surface_destroy(struct gbm_surface *surf)
 403 {
 404    surf->gbm->surface_destroy(surf);
 405 }
 406
 407 /**
 408  * Lock the surface's current front buffer
 409  *
 410  * Lock rendering to the surface's current front buffer until it is
 411  * released with gbm_surface_release_buffer().
 412  *
 413  * This function must be called exactly once after calling
 414  * eglSwapBuffers.  Calling it before any eglSwapBuffer has happened
 415  * on the surface or two or more times after eglSwapBuffers is an
 416  * error.  A new bo representing the new front buffer is returned.  On
 417  * multiple invocations, all the returned bos must be released in
 418  * order to release the actual surface buffer.
 419  *
 420  * \param surf The surface
 421  *
 422  * \return A buffer object that should be released with
 423  * gbm_surface_release_buffer() when no longer needed.  The implementation
 424  * is free to reuse buffers released with gbm_surface_release_buffer() so
 425  * this bo should not be destroyed using gbm_bo_destroy().  If an error
 426  * occurs this function returns %NULL.
 427  */
 428 GBM_EXPORT struct gbm_bo *
 429 gbm_surface_lock_front_buffer(struct gbm_surface *surf)
 430 {
 431    return surf->gbm->surface_lock_front_buffer(surf);
 432 }
 433
 434 /**
 435  * Release a locked buffer obtained with gbm_surface_lock_front_buffer()
 436  *
 437  * Returns the underlying buffer to the gbm surface.  Releasing a bo
 438  * will typically make gbm_surface_has_free_buffer() return 1 and thus
 439  * allow rendering the next frame, but not always. The implementation
 440  * may choose to destroy the bo immediately or reuse it, in which case
 441  * the user data associated with it is unchanged.
 442  *
 443  * \param surf The surface
 444  * \param bo The buffer object
 445  */
 446 GBM_EXPORT void
 447 gbm_surface_release_buffer(struct gbm_surface *surf, struct gbm_bo *bo)
 448 {
 449    surf->gbm->surface_release_buffer(surf, bo);
 450 }
 451
 452 /**
 453  * Return whether or not a surface has free (non-locked) buffers
 454  *
 455  * Before starting a new frame, the surface must have a buffer
 456  * available for rendering.  Initially, a gbm surface will have a free
 457  * buffer, but after one of more buffers have been locked (\sa
 458  * gbm_surface_lock_front_buffer()), the application must check for a
 459  * free buffer before rendering.
 460  *
 461  * If a surface doesn't have a free buffer, the application must
 462  * return a buffer to the surface using gbm_surface_release_buffer()
 463  * and after that, the application can query for free buffers again.
 464  *
 465  * \param surf The surface
 466  * \return 1 if the surface has free buffers, 0 otherwise
 467  */
 468 GBM_EXPORT int
 469 gbm_surface_has_free_buffers(struct gbm_surface *surf)
 470 {
 471    return surf->gbm->surface_has_free_buffers(surf);
 472 }