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
gbm_device_get_fd(struct gbm_device * gbm)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 *
gbm_device_get_backend_name(struct gbm_device * gbm)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
gbm_device_is_format_supported(struct gbm_device * gbm,uint32_t format,uint32_t usage)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
gbm_device_destroy(struct gbm_device * gbm)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 *
_gbm_mesa_get_device(int fd)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 *
gbm_create_device(int fd)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
gbm_bo_get_width(struct gbm_bo * bo)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
gbm_bo_get_height(struct gbm_bo * bo)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
gbm_bo_get_stride(struct gbm_bo * bo)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
gbm_bo_get_format(struct gbm_bo * bo)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
gbm_bo_get_handle(struct gbm_bo * bo)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
gbm_bo_write(struct gbm_bo * bo,const void * buf,size_t count)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 *
gbm_bo_get_device(struct gbm_bo * bo)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
gbm_bo_set_user_data(struct gbm_bo * bo,void * data,void (* destroy_user_data)(struct gbm_bo *,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 *
gbm_bo_get_user_data(struct gbm_bo * bo)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
gbm_bo_destroy(struct gbm_bo * bo)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 *
gbm_bo_create(struct gbm_device * gbm,uint32_t width,uint32_t height,uint32_t format,uint32_t usage)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 *
gbm_bo_import(struct gbm_device * gbm,uint32_t type,void * buffer,uint32_t usage)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 *
gbm_surface_create(struct gbm_device * gbm,uint32_t width,uint32_t height,uint32_t format,uint32_t flags)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
gbm_surface_destroy(struct gbm_surface * surf)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 *
gbm_surface_lock_front_buffer(struct gbm_surface * surf)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
gbm_surface_release_buffer(struct gbm_surface * surf,struct gbm_bo * bo)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
gbm_surface_has_free_buffers(struct gbm_surface * surf)469 gbm_surface_has_free_buffers(struct gbm_surface *surf)
470 {
471    return surf->gbm->surface_has_free_buffers(surf);
472 }
473