src/gallium/auxiliary/vl/vl_winsys_dri3.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2016 Advanced Micro Devices, Inc.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sub license, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28 #include <fcntl.h>
  29
  30 #include <X11/Xlib-xcb.h>
  31 #include <X11/xshmfence.h>
  32 #include <xcb/dri3.h>
  33 #include <xcb/present.h>
  34 #include <xcb/xfixes.h>
  35
  36 #include "loader.h"
  37
  38 #include "pipe/p_screen.h"
  39 #include "pipe/p_state.h"
  40 #include "pipe-loader/pipe_loader.h"
  41
  42 #include "util/u_memory.h"
  43 #include "util/u_inlines.h"
  44
  45 #include "vl/vl_compositor.h"
  46 #include "vl/vl_winsys.h"
  47
  48 #define BACK_BUFFER_NUM 3
  49
  50 struct vl_dri3_buffer
  51 {
  52    struct pipe_resource *texture;
  53    struct pipe_resource *linear_texture;
  54
  55    uint32_t pixmap;
  56    uint32_t sync_fence;
  57    struct xshmfence *shm_fence;
  58
  59    bool busy;
  60    uint32_t width, height, pitch;
  61 };
  62
  63 struct vl_dri3_screen
  64 {
  65    struct vl_screen base;
  66    xcb_connection_t *conn;
  67    xcb_drawable_t drawable;
  68
  69    uint32_t width, height, depth;
  70
  71    xcb_present_event_t eid;
  72    xcb_special_event_t *special_event;
  73
  74    struct pipe_context *pipe;
  75    struct pipe_resource *output_texture;
  76    uint32_t clip_width, clip_height;
  77
  78    struct vl_dri3_buffer *back_buffers[BACK_BUFFER_NUM];
  79    int cur_back;
  80    int next_back;
  81
  82    struct u_rect dirty_areas[BACK_BUFFER_NUM];
  83
  84    struct vl_dri3_buffer *front_buffer;
  85    bool is_pixmap;
  86
  87    uint32_t send_msc_serial, recv_msc_serial;
  88    uint64_t send_sbc, recv_sbc;
  89    int64_t last_ust, ns_frame, last_msc, next_msc;
  90
  91    bool is_different_gpu;
  92 };
  93
  94 static void
  95 dri3_free_front_buffer(struct vl_dri3_screen *scrn,
  96                         struct vl_dri3_buffer *buffer)
  97 {
  98    xcb_sync_destroy_fence(scrn->conn, buffer->sync_fence);
  99    xshmfence_unmap_shm(buffer->shm_fence);
 100    pipe_resource_reference(&buffer->texture, NULL);
 101    FREE(buffer);
 102 }
 103
 104 static void
 105 dri3_free_back_buffer(struct vl_dri3_screen *scrn,
 106                         struct vl_dri3_buffer *buffer)
 107 {
 108    xcb_free_pixmap(scrn->conn, buffer->pixmap);
 109    xcb_sync_destroy_fence(scrn->conn, buffer->sync_fence);
 110    xshmfence_unmap_shm(buffer->shm_fence);
 111    if (!scrn->output_texture)
 112       pipe_resource_reference(&buffer->texture, NULL);
 113    if (buffer->linear_texture)
 114        pipe_resource_reference(&buffer->linear_texture, NULL);
 115    FREE(buffer);
 116 }
 117
 118 static void
 119 dri3_handle_stamps(struct vl_dri3_screen *scrn, uint64_t ust, uint64_t msc)
 120 {
 121    int64_t ust_ns =  ust * 1000;
 122
 123    if (scrn->last_ust && (ust_ns > scrn->last_ust) &&
 124        scrn->last_msc && (msc > scrn->last_msc))
 125       scrn->ns_frame = (ust_ns - scrn->last_ust) / (msc - scrn->last_msc);
 126
 127    scrn->last_ust = ust_ns;
 128    scrn->last_msc = msc;
 129 }
 130
 131 static void
 132 dri3_handle_present_event(struct vl_dri3_screen *scrn,
 133                           xcb_present_generic_event_t *ge)
 134 {
 135    switch (ge->evtype) {
 136    case XCB_PRESENT_CONFIGURE_NOTIFY: {
 137       xcb_present_configure_notify_event_t *ce = (void *) ge;
 138       scrn->width = ce->width;
 139       scrn->height = ce->height;
 140       break;
 141    }
 142    case XCB_PRESENT_COMPLETE_NOTIFY: {
 143       xcb_present_complete_notify_event_t *ce = (void *) ge;
 144       if (ce->kind == XCB_PRESENT_COMPLETE_KIND_PIXMAP) {
 145          scrn->recv_sbc = (scrn->send_sbc & 0xffffffff00000000LL) | ce->serial;
 146          if (scrn->recv_sbc > scrn->send_sbc)
 147             scrn->recv_sbc -= 0x100000000;
 148          dri3_handle_stamps(scrn, ce->ust, ce->msc);
 149       } else if (ce->kind == XCB_PRESENT_COMPLETE_KIND_NOTIFY_MSC) {
 150          scrn->recv_msc_serial = ce->serial;
 151          dri3_handle_stamps(scrn, ce->ust, ce->msc);
 152       }
 153       break;
 154    }
 155    case XCB_PRESENT_EVENT_IDLE_NOTIFY: {
 156       xcb_present_idle_notify_event_t *ie = (void *) ge;
 157       int b;
 158       for (b = 0; b < BACK_BUFFER_NUM; b++) {
 159          struct vl_dri3_buffer *buf = scrn->back_buffers[b];
 160          if (buf && buf->pixmap == ie->pixmap) {
 161             buf->busy = false;
 162             break;
 163          }
 164       }
 165       break;
 166    }
 167    }
 168    free(ge);
 169 }
 170
 171 static void
 172 dri3_flush_present_events(struct vl_dri3_screen *scrn)
 173 {
 174    if (scrn->special_event) {
 175       xcb_generic_event_t *ev;
 176       while ((ev = xcb_poll_for_special_event(
 177                    scrn->conn, scrn->special_event)) != NULL)
 178          dri3_handle_present_event(scrn, (xcb_present_generic_event_t *)ev);
 179    }
 180 }
 181
 182 static bool
 183 dri3_wait_present_events(struct vl_dri3_screen *scrn)
 184 {
 185    if (scrn->special_event) {
 186       xcb_generic_event_t *ev;
 187       ev = xcb_wait_for_special_event(scrn->conn, scrn->special_event);
 188       if (!ev)
 189          return false;
 190       dri3_handle_present_event(scrn, (xcb_present_generic_event_t *)ev);
 191       return true;
 192    }
 193    return false;
 194 }
 195
 196 static int
 197 dri3_find_back(struct vl_dri3_screen *scrn)
 198 {
 199    int b;
 200
 201    for (;;) {
 202       for (b = 0; b < BACK_BUFFER_NUM; b++) {
 203          int id = (b + scrn->cur_back) % BACK_BUFFER_NUM;
 204          struct vl_dri3_buffer *buffer = scrn->back_buffers[id];
 205          if (!buffer || !buffer->busy)
 206             return id;
 207       }
 208       xcb_flush(scrn->conn);
 209       if (!dri3_wait_present_events(scrn))
 210          return -1;
 211    }
 212 }
 213
 214 static struct vl_dri3_buffer *
 215 dri3_alloc_back_buffer(struct vl_dri3_screen *scrn)
 216 {
 217    struct vl_dri3_buffer *buffer;
 218    xcb_pixmap_t pixmap;
 219    xcb_sync_fence_t sync_fence;
 220    struct xshmfence *shm_fence;
 221    int buffer_fd, fence_fd;
 222    struct pipe_resource templ, *pixmap_buffer_texture;
 223    struct winsys_handle whandle;
 224
 225    buffer = CALLOC_STRUCT(vl_dri3_buffer);
 226    if (!buffer)
 227       return NULL;
 228
 229    fence_fd = xshmfence_alloc_shm();
 230    if (fence_fd < 0)
 231       goto free_buffer;
 232
 233    shm_fence = xshmfence_map_shm(fence_fd);
 234    if (!shm_fence)
 235       goto close_fd;
 236
 237    memset(&templ, 0, sizeof(templ));
 238    templ.bind = PIPE_BIND_RENDER_TARGET | PIPE_BIND_SAMPLER_VIEW;
 239    templ.format = vl_dri2_format_for_depth(&scrn->base, scrn->depth);
 240    templ.target = PIPE_TEXTURE_2D;
 241    templ.last_level = 0;
 242    templ.width0 = (scrn->output_texture) ?
 243                   scrn->output_texture->width0 : scrn->width;
 244    templ.height0 = (scrn->output_texture) ?
 245                    scrn->output_texture->height0 : scrn->height;
 246    templ.depth0 = 1;
 247    templ.array_size = 1;
 248
 249    if (scrn->is_different_gpu) {
 250       buffer->texture = (scrn->output_texture) ? scrn->output_texture :
 251                         scrn->base.pscreen->resource_create(scrn->base.pscreen, &templ);
 252       if (!buffer->texture)
 253          goto unmap_shm;
 254
 255       templ.bind |= PIPE_BIND_SCANOUT | PIPE_BIND_SHARED |
 256                     PIPE_BIND_LINEAR;
 257       buffer->linear_texture =
 258           scrn->base.pscreen->resource_create(scrn->base.pscreen, &templ);
 259       pixmap_buffer_texture = buffer->linear_texture;
 260
 261       if (!buffer->linear_texture)
 262          goto no_linear_texture;
 263    } else {
 264       templ.bind |= PIPE_BIND_SCANOUT | PIPE_BIND_SHARED;
 265       buffer->texture = (scrn->output_texture) ? scrn->output_texture :
 266                         scrn->base.pscreen->resource_create(scrn->base.pscreen, &templ);
 267       if (!buffer->texture)
 268          goto unmap_shm;
 269       pixmap_buffer_texture = buffer->texture;
 270    }
 271    memset(&whandle, 0, sizeof(whandle));
 272    whandle.type= WINSYS_HANDLE_TYPE_FD;
 273    scrn->base.pscreen->resource_get_handle(scrn->base.pscreen, NULL,
 274                                            pixmap_buffer_texture, &whandle, 0);
 275    buffer_fd = whandle.handle;
 276    buffer->pitch = whandle.stride;
 277    buffer->width = templ.width0;
 278    buffer->height = templ.height0;
 279
 280    xcb_dri3_pixmap_from_buffer(scrn->conn,
 281                                (pixmap = xcb_generate_id(scrn->conn)),
 282                                scrn->drawable,
 283                                0,
 284                                buffer->width, buffer->height, buffer->pitch,
 285                                scrn->depth, 32,
 286                                buffer_fd);
 287    xcb_dri3_fence_from_fd(scrn->conn,
 288                           pixmap,
 289                           (sync_fence = xcb_generate_id(scrn->conn)),
 290                           false,
 291                           fence_fd);
 292
 293    buffer->pixmap = pixmap;
 294    buffer->sync_fence = sync_fence;
 295    buffer->shm_fence = shm_fence;
 296
 297    xshmfence_trigger(buffer->shm_fence);
 298
 299    return buffer;
 300
 301 no_linear_texture:
 302    pipe_resource_reference(&buffer->texture, NULL);
 303 unmap_shm:
 304    xshmfence_unmap_shm(shm_fence);
 305 close_fd:
 306    close(fence_fd);
 307 free_buffer:
 308    FREE(buffer);
 309    return NULL;
 310 }
 311
 312 static struct vl_dri3_buffer *
 313 dri3_get_back_buffer(struct vl_dri3_screen *scrn)
 314 {
 315    struct vl_dri3_buffer *buffer;
 316    struct pipe_resource *texture = NULL;
 317    bool allocate_new_buffer = false;
 318    int b, id;
 319
 320    assert(scrn);
 321
 322    scrn->cur_back = dri3_find_back(scrn);
 323    if (scrn->cur_back < 0)
 324       return NULL;
 325    buffer = scrn->back_buffers[scrn->cur_back];
 326
 327    if (scrn->output_texture) {
 328       if (!buffer || buffer->width < scrn->width ||
 329           buffer->height < scrn->height)
 330          allocate_new_buffer = true;
 331       else if (scrn->is_different_gpu)
 332          /* In case of different gpu we can reuse the linear
 333           * texture so we only need to set the external
 334           * texture for copying
 335           */
 336          buffer->texture = scrn->output_texture;
 337       else {
 338          /* In case of a single gpu we search if the texture is
 339           * already present as buffer if not we get the
 340           * handle and pixmap for the texture that is set
 341           */
 342          for (b = 0; b < BACK_BUFFER_NUM; b++) {
 343             id = (b + scrn->cur_back) % BACK_BUFFER_NUM;
 344             buffer = scrn->back_buffers[id];
 345             if (buffer && !buffer->busy &&
 346                 buffer->texture == scrn->output_texture) {
 347                scrn->cur_back = id;
 348                break;
 349             }
 350          }
 351
 352          if (b == BACK_BUFFER_NUM) {
 353             allocate_new_buffer = true;
 354             scrn->cur_back = scrn->next_back;
 355             scrn->next_back = (scrn->next_back + 1) % BACK_BUFFER_NUM;
 356             buffer = scrn->back_buffers[scrn->cur_back];
 357          }
 358       }
 359
 360    } else {
 361       if (!buffer || buffer->width != scrn->width ||
 362           buffer->height != scrn->height)
 363          allocate_new_buffer = true;
 364    }
 365
 366    if (allocate_new_buffer) {
 367       struct vl_dri3_buffer *new_buffer;
 368
 369       new_buffer = dri3_alloc_back_buffer(scrn);
 370       if (!new_buffer)
 371          return NULL;
 372
 373       if (buffer)
 374          dri3_free_back_buffer(scrn, buffer);
 375
 376       if (!scrn->output_texture)
 377          vl_compositor_reset_dirty_area(&scrn->dirty_areas[scrn->cur_back]);
 378       buffer = new_buffer;
 379       scrn->back_buffers[scrn->cur_back] = buffer;
 380    }
 381
 382    pipe_resource_reference(&texture, buffer->texture);
 383    xcb_flush(scrn->conn);
 384    xshmfence_await(buffer->shm_fence);
 385
 386    return buffer;
 387 }
 388
 389 static bool
 390 dri3_set_drawable(struct vl_dri3_screen *scrn, Drawable drawable)
 391 {
 392    xcb_get_geometry_cookie_t geom_cookie;
 393    xcb_get_geometry_reply_t *geom_reply;
 394    xcb_void_cookie_t cookie;
 395    xcb_generic_error_t *error;
 396    bool ret = true;
 397
 398    assert(drawable);
 399
 400    if (scrn->drawable == drawable)
 401       return true;
 402
 403    scrn->drawable = drawable;
 404
 405    geom_cookie = xcb_get_geometry(scrn->conn, scrn->drawable);
 406    geom_reply = xcb_get_geometry_reply(scrn->conn, geom_cookie, NULL);
 407    if (!geom_reply)
 408       return false;
 409
 410    scrn->width = geom_reply->width;
 411    scrn->height = geom_reply->height;
 412    scrn->depth = geom_reply->depth;
 413    free(geom_reply);
 414
 415    if (scrn->special_event) {
 416       xcb_unregister_for_special_event(scrn->conn, scrn->special_event);
 417       scrn->special_event = NULL;
 418       cookie = xcb_present_select_input_checked(scrn->conn, scrn->eid,
 419                                                 scrn->drawable,
 420                                                 XCB_PRESENT_EVENT_MASK_NO_EVENT);
 421       xcb_discard_reply(scrn->conn, cookie.sequence);
 422    }
 423
 424    scrn->is_pixmap = false;
 425    scrn->eid = xcb_generate_id(scrn->conn);
 426    cookie =
 427       xcb_present_select_input_checked(scrn->conn, scrn->eid, scrn->drawable,
 428                       XCB_PRESENT_EVENT_MASK_CONFIGURE_NOTIFY |
 429                       XCB_PRESENT_EVENT_MASK_COMPLETE_NOTIFY |
 430                       XCB_PRESENT_EVENT_MASK_IDLE_NOTIFY);
 431
 432    error = xcb_request_check(scrn->conn, cookie);
 433    if (error) {
 434       if (error->error_code != BadWindow)
 435          ret = false;
 436       else {
 437          scrn->is_pixmap = true;
 438          scrn->base.set_back_texture_from_output = NULL;
 439          if (scrn->front_buffer) {
 440             dri3_free_front_buffer(scrn, scrn->front_buffer);
 441             scrn->front_buffer = NULL;
 442          }
 443       }
 444       free(error);
 445    } else
 446       scrn->special_event =
 447          xcb_register_for_special_xge(scrn->conn, &xcb_present_id, scrn->eid, 0);
 448
 449    dri3_flush_present_events(scrn);
 450
 451    return ret;
 452 }
 453
 454 static struct vl_dri3_buffer *
 455 dri3_get_front_buffer(struct vl_dri3_screen *scrn)
 456 {
 457    xcb_dri3_buffer_from_pixmap_cookie_t bp_cookie;
 458    xcb_dri3_buffer_from_pixmap_reply_t *bp_reply;
 459    xcb_sync_fence_t sync_fence;
 460    struct xshmfence *shm_fence;
 461    int fence_fd, *fds;
 462    struct winsys_handle whandle;
 463    struct pipe_resource templ, *texture = NULL;
 464
 465    if (scrn->front_buffer) {
 466       pipe_resource_reference(&texture, scrn->front_buffer->texture);
 467       return scrn->front_buffer;
 468    }
 469
 470    scrn->front_buffer = CALLOC_STRUCT(vl_dri3_buffer);
 471    if (!scrn->front_buffer)
 472       return NULL;
 473
 474    fence_fd = xshmfence_alloc_shm();
 475    if (fence_fd < 0)
 476       goto free_buffer;
 477
 478    shm_fence = xshmfence_map_shm(fence_fd);
 479    if (!shm_fence)
 480       goto close_fd;
 481
 482    bp_cookie = xcb_dri3_buffer_from_pixmap(scrn->conn, scrn->drawable);
 483    bp_reply = xcb_dri3_buffer_from_pixmap_reply(scrn->conn, bp_cookie, NULL);
 484    if (!bp_reply)
 485       goto unmap_shm;
 486
 487    fds = xcb_dri3_buffer_from_pixmap_reply_fds(scrn->conn, bp_reply);
 488    if (fds[0] < 0)
 489       goto free_reply;
 490
 491    memset(&whandle, 0, sizeof(whandle));
 492    whandle.type = WINSYS_HANDLE_TYPE_FD;
 493    whandle.handle = (unsigned)fds[0];
 494    whandle.stride = bp_reply->stride;
 495    memset(&templ, 0, sizeof(templ));
 496    templ.bind = PIPE_BIND_RENDER_TARGET | PIPE_BIND_SAMPLER_VIEW;
 497    templ.format = vl_dri2_format_for_depth(&scrn->base, bp_reply->depth);
 498    templ.target = PIPE_TEXTURE_2D;
 499    templ.last_level = 0;
 500    templ.width0 = bp_reply->width;
 501    templ.height0 = bp_reply->height;
 502    templ.depth0 = 1;
 503    templ.array_size = 1;
 504    scrn->front_buffer->texture =
 505       scrn->base.pscreen->resource_from_handle(scrn->base.pscreen,
 506                                                &templ, &whandle,
 507                                                PIPE_HANDLE_USAGE_FRAMEBUFFER_WRITE);
 508    close(fds[0]);
 509    if (!scrn->front_buffer->texture)
 510       goto free_reply;
 511
 512    xcb_dri3_fence_from_fd(scrn->conn,
 513                           scrn->drawable,
 514                           (sync_fence = xcb_generate_id(scrn->conn)),
 515                           false,
 516                           fence_fd);
 517
 518    pipe_resource_reference(&texture, scrn->front_buffer->texture);
 519    scrn->front_buffer->pixmap = scrn->drawable;
 520    scrn->front_buffer->width = bp_reply->width;
 521    scrn->front_buffer->height = bp_reply->height;
 522    scrn->front_buffer->shm_fence = shm_fence;
 523    scrn->front_buffer->sync_fence = sync_fence;
 524    free(bp_reply);
 525
 526    return scrn->front_buffer;
 527
 528 free_reply:
 529    free(bp_reply);
 530 unmap_shm:
 531    xshmfence_unmap_shm(shm_fence);
 532 close_fd:
 533    close(fence_fd);
 534 free_buffer:
 535    FREE(scrn->front_buffer);
 536    return NULL;
 537 }
 538
 539 static xcb_screen_t *
 540 dri3_get_screen_for_root(xcb_connection_t *conn, xcb_window_t root)
 541 {
 542    xcb_screen_iterator_t screen_iter =
 543    xcb_setup_roots_iterator(xcb_get_setup(conn));
 544
 545    for (; screen_iter.rem; xcb_screen_next (&screen_iter)) {
 546       if (screen_iter.data->root == root)
 547          return screen_iter.data;
 548    }
 549
 550    return NULL;
 551 }
 552
 553 static void
 554 vl_dri3_flush_frontbuffer(struct pipe_screen *screen,
 555                           struct pipe_resource *resource,
 556                           unsigned level, unsigned layer,
 557                           void *context_private, struct pipe_box *sub_box)
 558 {
 559    struct vl_dri3_screen *scrn = (struct vl_dri3_screen *)context_private;
 560    uint32_t options = XCB_PRESENT_OPTION_NONE;
 561    struct vl_dri3_buffer *back;
 562    struct pipe_box src_box;
 563    xcb_xfixes_region_t region;
 564    xcb_rectangle_t rectangle;
 565
 566    back = scrn->back_buffers[scrn->cur_back];
 567    if (!back)
 568        return;
 569
 570    while (scrn->special_event && scrn->recv_sbc < scrn->send_sbc)
 571       if (!dri3_wait_present_events(scrn))
 572          return;
 573
 574    rectangle.x = 0;
 575    rectangle.y = 0;
 576    rectangle.width = (scrn->output_texture) ? scrn->clip_width : scrn->width;
 577    rectangle.height = (scrn->output_texture) ? scrn->clip_height : scrn->height;
 578
 579    region = xcb_generate_id(scrn->conn);
 580    xcb_xfixes_create_region(scrn->conn, region, 2, &rectangle);
 581
 582    if (scrn->is_different_gpu) {
 583       u_box_origin_2d(back->width, back->height, &src_box);
 584       scrn->pipe->resource_copy_region(scrn->pipe,
 585                                        back->linear_texture,
 586                                        0, 0, 0, 0,
 587                                        back->texture,
 588                                        0, &src_box);
 589
 590       scrn->pipe->flush(scrn->pipe, NULL, 0);
 591    }
 592    xshmfence_reset(back->shm_fence);
 593    back->busy = true;
 594
 595    xcb_present_pixmap(scrn->conn,
 596                       scrn->drawable,
 597                       back->pixmap,
 598                       (uint32_t)(++scrn->send_sbc),
 599                       0, region, 0, 0,
 600                       None, None,
 601                       back->sync_fence,
 602                       options,
 603                       scrn->next_msc,
 604                       0, 0, 0, NULL);
 605
 606    xcb_flush(scrn->conn);
 607
 608    return;
 609 }
 610
 611 static struct pipe_resource *
 612 vl_dri3_screen_texture_from_drawable(struct vl_screen *vscreen, void *drawable)
 613 {
 614    struct vl_dri3_screen *scrn = (struct vl_dri3_screen *)vscreen;
 615    struct vl_dri3_buffer *buffer;
 616
 617    assert(scrn);
 618
 619    if (!dri3_set_drawable(scrn, (Drawable)drawable))
 620       return NULL;
 621
 622    buffer = (scrn->is_pixmap) ?
 623             dri3_get_front_buffer(scrn) :
 624             dri3_get_back_buffer(scrn);
 625    if (!buffer)
 626       return NULL;
 627
 628    return buffer->texture;
 629 }
 630
 631 static struct u_rect *
 632 vl_dri3_screen_get_dirty_area(struct vl_screen *vscreen)
 633 {
 634    struct vl_dri3_screen *scrn = (struct vl_dri3_screen *)vscreen;
 635
 636    assert(scrn);
 637
 638    return &scrn->dirty_areas[scrn->cur_back];
 639 }
 640
 641 static uint64_t
 642 vl_dri3_screen_get_timestamp(struct vl_screen *vscreen, void *drawable)
 643 {
 644    struct vl_dri3_screen *scrn = (struct vl_dri3_screen *)vscreen;
 645
 646    assert(scrn);
 647
 648    if (!dri3_set_drawable(scrn, (Drawable)drawable))
 649       return 0;
 650
 651    if (!scrn->last_ust) {
 652       xcb_present_notify_msc(scrn->conn,
 653                              scrn->drawable,
 654                              ++scrn->send_msc_serial,
 655                              0, 0, 0);
 656       xcb_flush(scrn->conn);
 657
 658       while (scrn->special_event &&
 659              scrn->send_msc_serial > scrn->recv_msc_serial) {
 660          if (!dri3_wait_present_events(scrn))
 661             return 0;
 662       }
 663    }
 664
 665    return scrn->last_ust;
 666 }
 667
 668 static void
 669 vl_dri3_screen_set_next_timestamp(struct vl_screen *vscreen, uint64_t stamp)
 670 {
 671    struct vl_dri3_screen *scrn = (struct vl_dri3_screen *)vscreen;
 672
 673    assert(scrn);
 674
 675    if (stamp && scrn->last_ust && scrn->ns_frame && scrn->last_msc)
 676       scrn->next_msc = ((int64_t)stamp - scrn->last_ust + scrn->ns_frame/2) /
 677                        scrn->ns_frame + scrn->last_msc;
 678    else
 679       scrn->next_msc = 0;
 680 }
 681
 682 static void *
 683 vl_dri3_screen_get_private(struct vl_screen *vscreen)
 684 {
 685    return vscreen;
 686 }
 687
 688 static void
 689 vl_dri3_screen_set_back_texture_from_output(struct vl_screen *vscreen,
 690                                             struct pipe_resource *buffer,
 691                                             uint32_t width, uint32_t height)
 692 {
 693    struct vl_dri3_screen *scrn = (struct vl_dri3_screen *)vscreen;
 694
 695    assert(scrn);
 696
 697    scrn->output_texture = buffer;
 698    scrn->clip_width = (width) ? width : scrn->width;
 699    scrn->clip_height = (height) ? height : scrn->height;
 700 }
 701
 702 static void
 703 vl_dri3_screen_destroy(struct vl_screen *vscreen)
 704 {
 705    struct vl_dri3_screen *scrn = (struct vl_dri3_screen *)vscreen;
 706    int i;
 707
 708    assert(vscreen);
 709
 710    dri3_flush_present_events(scrn);
 711
 712    if (scrn->front_buffer) {
 713       dri3_free_front_buffer(scrn, scrn->front_buffer);
 714       scrn->front_buffer = NULL;
 715    }
 716
 717    for (i = 0; i < BACK_BUFFER_NUM; ++i) {
 718       if (scrn->back_buffers[i]) {
 719          dri3_free_back_buffer(scrn, scrn->back_buffers[i]);
 720          scrn->back_buffers[i] = NULL;
 721       }
 722    }
 723
 724    if (scrn->special_event) {
 725       xcb_void_cookie_t cookie =
 726          xcb_present_select_input_checked(scrn->conn, scrn->eid,
 727                                           scrn->drawable,
 728                                           XCB_PRESENT_EVENT_MASK_NO_EVENT);
 729
 730       xcb_discard_reply(scrn->conn, cookie.sequence);
 731       xcb_unregister_for_special_event(scrn->conn, scrn->special_event);
 732    }
 733    scrn->pipe->destroy(scrn->pipe);
 734    scrn->base.pscreen->destroy(scrn->base.pscreen);
 735    pipe_loader_release(&scrn->base.dev, 1);
 736    FREE(scrn);
 737
 738    return;
 739 }
 740
 741 struct vl_screen *
 742 vl_dri3_screen_create(Display *display, int screen)
 743 {
 744    struct vl_dri3_screen *scrn;
 745    const xcb_query_extension_reply_t *extension;
 746    xcb_dri3_open_cookie_t open_cookie;
 747    xcb_dri3_open_reply_t *open_reply;
 748    xcb_get_geometry_cookie_t geom_cookie;
 749    xcb_get_geometry_reply_t *geom_reply;
 750    xcb_xfixes_query_version_cookie_t xfixes_cookie;
 751    xcb_xfixes_query_version_reply_t *xfixes_reply;
 752    xcb_generic_error_t *error;
 753    int fd;
 754
 755    assert(display);
 756
 757    scrn = CALLOC_STRUCT(vl_dri3_screen);
 758    if (!scrn)
 759       return NULL;
 760
 761    scrn->conn = XGetXCBConnection(display);
 762    if (!scrn->conn)
 763       goto free_screen;
 764
 765    xcb_prefetch_extension_data(scrn->conn , &xcb_dri3_id);
 766    xcb_prefetch_extension_data(scrn->conn, &xcb_present_id);
 767    xcb_prefetch_extension_data (scrn->conn, &xcb_xfixes_id);
 768    extension = xcb_get_extension_data(scrn->conn, &xcb_dri3_id);
 769    if (!(extension && extension->present))
 770       goto free_screen;
 771    extension = xcb_get_extension_data(scrn->conn, &xcb_present_id);
 772    if (!(extension && extension->present))
 773       goto free_screen;
 774    extension = xcb_get_extension_data(scrn->conn, &xcb_xfixes_id);
 775    if (!(extension && extension->present))
 776       goto free_screen;
 777
 778    xfixes_cookie = xcb_xfixes_query_version(scrn->conn, XCB_XFIXES_MAJOR_VERSION,
 779                                             XCB_XFIXES_MINOR_VERSION);
 780    xfixes_reply = xcb_xfixes_query_version_reply(scrn->conn, xfixes_cookie, &error);
 781    if (!xfixes_reply || error || xfixes_reply->major_version < 2) {
 782       free(error);
 783       free(xfixes_reply);
 784       goto free_screen;
 785    }
 786    free(xfixes_reply);
 787
 788    open_cookie = xcb_dri3_open(scrn->conn, RootWindow(display, screen), None);
 789    open_reply = xcb_dri3_open_reply(scrn->conn, open_cookie, NULL);
 790    if (!open_reply)
 791       goto free_screen;
 792    if (open_reply->nfd != 1) {
 793       free(open_reply);
 794       goto free_screen;
 795    }
 796
 797    fd = xcb_dri3_open_reply_fds(scrn->conn, open_reply)[0];
 798    if (fd < 0) {
 799       free(open_reply);
 800       goto free_screen;
 801    }
 802    fcntl(fd, F_SETFD, FD_CLOEXEC);
 803    free(open_reply);
 804
 805    fd = loader_get_user_preferred_fd(fd, &scrn->is_different_gpu);
 806
 807    geom_cookie = xcb_get_geometry(scrn->conn, RootWindow(display, screen));
 808    geom_reply = xcb_get_geometry_reply(scrn->conn, geom_cookie, NULL);
 809    if (!geom_reply)
 810       goto close_fd;
 811
 812    scrn->base.xcb_screen = dri3_get_screen_for_root(scrn->conn, geom_reply->root);
 813    if (!scrn->base.xcb_screen) {
 814       free(geom_reply);
 815       goto close_fd;
 816    }
 817
 818    /* TODO support depth other than 24 or 30 */
 819    if (geom_reply->depth != 24 && geom_reply->depth != 30) {
 820       free(geom_reply);
 821       goto close_fd;
 822    }
 823    scrn->base.color_depth = geom_reply->depth;
 824    free(geom_reply);
 825
 826    if (pipe_loader_drm_probe_fd(&scrn->base.dev, fd))
 827       scrn->base.pscreen = pipe_loader_create_screen(scrn->base.dev);
 828
 829    if (!scrn->base.pscreen)
 830       goto release_pipe;
 831
 832    scrn->pipe = pipe_create_multimedia_context(scrn->base.pscreen);
 833    if (!scrn->pipe)
 834        goto no_context;
 835
 836    scrn->base.destroy = vl_dri3_screen_destroy;
 837    scrn->base.texture_from_drawable = vl_dri3_screen_texture_from_drawable;
 838    scrn->base.get_dirty_area = vl_dri3_screen_get_dirty_area;
 839    scrn->base.get_timestamp = vl_dri3_screen_get_timestamp;
 840    scrn->base.set_next_timestamp = vl_dri3_screen_set_next_timestamp;
 841    scrn->base.get_private = vl_dri3_screen_get_private;
 842    scrn->base.pscreen->flush_frontbuffer = vl_dri3_flush_frontbuffer;
 843    scrn->base.set_back_texture_from_output = vl_dri3_screen_set_back_texture_from_output;
 844
 845    scrn->next_back = 1;
 846    return &scrn->base;
 847
 848 no_context:
 849    scrn->base.pscreen->destroy(scrn->base.pscreen);
 850 release_pipe:
 851    if (scrn->base.dev) {
 852       pipe_loader_release(&scrn->base.dev, 1);
 853       fd = -1;
 854    }
 855 close_fd:
 856    if (fd != -1)
 857       close(fd);
 858 free_screen:
 859    FREE(scrn);
 860    return NULL;
 861 }