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/**************************************************************************

 *

 * Copyright 2003 Tungsten Graphics, Inc., Cedar Park, Texas.

 * All Rights Reserved.

 *

 * Permission is hereby granted, free of charge, to any person obtaining a

 * copy of this software and associated documentation files (the

 * "Software"), to deal in the Software without restriction, including

 * without limitation the rights to use, copy, modify, merge, publish,

 * distribute, sub license, and/or sell copies of the Software, and to

 * permit persons to whom the Software is furnished to do so, subject to

 * the following conditions:

 *

 * The above copyright notice and this permission notice (including the

 * next paragraph) shall be included in all copies or substantial portions

 * of the Software.

 *

 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS

 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF

 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.

 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR

 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,

 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE

 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

 *

 **************************************************************************/

#include "main/glheader.h"

#include "main/context.h"

#include "main/extensions.h"

#include "main/fbobject.h"

#include "main/framebuffer.h"

#include "main/imports.h"

#include "main/points.h"

#include "main/renderbuffer.h"

#include "swrast/swrast.h"

#include "swrast_setup/swrast_setup.h"

#include "tnl/tnl.h"

#include "drivers/common/driverfuncs.h"

#include "drivers/common/meta.h"

#include "intel_chipset.h"

#include "intel_buffers.h"

#include "intel_tex.h"

#include "intel_batchbuffer.h"

#include "intel_clear.h"

#include "intel_extensions.h"

#include "intel_pixel.h"

#include "intel_regions.h"

#include "intel_buffer_objects.h"

#include "intel_fbo.h"

#include "intel_bufmgr.h"

#include "intel_screen.h"

#include "intel_mipmap_tree.h"

#include "utils.h"

#include "../glsl/ralloc.h"

#ifndef INTEL_DEBUG

int INTEL_DEBUG = (0);

#endif

static const GLubyte *

intelGetString(struct gl_context * ctx, GLenum name)

{

   const struct intel_context *const intel = intel_context(ctx);

   const char *chipset;

   static char buffer[128];

   static char driver_name[] = "i915_dri.drv";

   switch (name) {

   case GL_VENDOR:

      return (GLubyte *) "Intel Open Source Technology Center";

      break;

   case GL_RENDERER:

      switch (intel->intelScreen->deviceID) {

#undef CHIPSET

#define CHIPSET(id, symbol, str) case id: chipset = str; break;

#include "pci_ids/i915_pci_ids.h"

      default:

         chipset = "Unknown Intel Chipset";

         break;

      }

      (void) driGetRendererString(buffer, chipset, 0);

      return (GLubyte *) buffer;

   case 0x1F04:  /* GL_DRIVER_NAME */

      return (GLubyte*)driver_name;

   default:

      return NULL;

   }

}

static void

intel_flush_front(struct gl_context *ctx)

{

   struct intel_context *intel = intel_context(ctx);

    __DRIcontext *driContext = intel->driContext;

    __DRIdrawable *driDrawable = driContext->driDrawablePriv;

    __DRIscreen *const screen = intel->intelScreen->driScrnPriv;

    if (intel->front_buffer_dirty && _mesa_is_winsys_fbo(ctx->DrawBuffer)) {

      if (screen->dri2.loader->flushFrontBuffer != NULL &&

          driDrawable &&

          driDrawable->loaderPrivate) {

         screen->dri2.loader->flushFrontBuffer(driDrawable,

                                               driDrawable->loaderPrivate);

	 /* We set the dirty bit in intel_prepare_render() if we're

	  * front buffer rendering once we get there.

	  */

	 intel->front_buffer_dirty = false;

      }

   }

}

static unsigned

intel_bits_per_pixel(const struct intel_renderbuffer *rb)

{

   return _mesa_get_format_bytes(intel_rb_format(rb)) * 8;

}

static void

intel_query_dri2_buffers(struct intel_context *intel,

			 __DRIdrawable *drawable,

			 __DRIbuffer **buffers,

			 int *count);

static void

intel_process_dri2_buffer(struct intel_context *intel,

			  __DRIdrawable *drawable,

			  __DRIbuffer *buffer,

			  struct intel_renderbuffer *rb,

			  const char *buffer_name);

void

intel_update_renderbuffers(__DRIcontext *context, __DRIdrawable *drawable)

{

   struct gl_framebuffer *fb = drawable->driverPrivate;

   struct intel_renderbuffer *rb;

   struct intel_context *intel = context->driverPrivate;

   __DRIbuffer *buffers = NULL;

   int i, count;

   const char *region_name;

   /* Set this up front, so that in case our buffers get invalidated

    * while we're getting new buffers, we don't clobber the stamp and

    * thus ignore the invalidate. */

   drawable->lastStamp = drawable->dri2.stamp;

   if (unlikely(INTEL_DEBUG & DEBUG_DRI))

      fprintf(stderr, "enter %s, drawable %p\n", __func__, drawable);

   intel_query_dri2_buffers(intel, drawable, &buffers, &count);

   if (buffers == NULL)

      return;

   for (i = 0; i < count; i++) {

       switch (buffers[i].attachment) {

       case __DRI_BUFFER_FRONT_LEFT:

	   rb = intel_get_renderbuffer(fb, BUFFER_FRONT_LEFT);

	   region_name = "dri2 front buffer";

	   break;

       case __DRI_BUFFER_FAKE_FRONT_LEFT:

	   rb = intel_get_renderbuffer(fb, BUFFER_FRONT_LEFT);

	   region_name = "dri2 fake front buffer";

	   break;

       case __DRI_BUFFER_BACK_LEFT:

	   rb = intel_get_renderbuffer(fb, BUFFER_BACK_LEFT);

	   region_name = "dri2 back buffer";

	   break;

       case __DRI_BUFFER_DEPTH:

       case __DRI_BUFFER_HIZ:

       case __DRI_BUFFER_DEPTH_STENCIL:

       case __DRI_BUFFER_STENCIL:

       case __DRI_BUFFER_ACCUM:

       default:

	   fprintf(stderr,

		   "unhandled buffer attach event, attachment type %d\n",

		   buffers[i].attachment);

	   return;

       }

       intel_process_dri2_buffer(intel, drawable, &buffers[i], rb, region_name);

   }

   driUpdateFramebufferSize(&intel->ctx, drawable);

}

/**

 * intel_prepare_render should be called anywhere that curent read/drawbuffer

 * state is required.

 */

void

intel_prepare_render(struct intel_context *intel)

{

   __DRIcontext *driContext = intel->driContext;

   __DRIdrawable *drawable;

   drawable = driContext->driDrawablePriv;

   if (drawable && drawable->dri2.stamp != driContext->dri2.draw_stamp) {

      if (drawable->lastStamp != drawable->dri2.stamp)

	 intel_update_renderbuffers(driContext, drawable);

      intel_draw_buffer(&intel->ctx);

      driContext->dri2.draw_stamp = drawable->dri2.stamp;

   }

   drawable = driContext->driReadablePriv;

   if (drawable && drawable->dri2.stamp != driContext->dri2.read_stamp) {

      if (drawable->lastStamp != drawable->dri2.stamp)

	 intel_update_renderbuffers(driContext, drawable);

      driContext->dri2.read_stamp = drawable->dri2.stamp;

   }

   /* If we're currently rendering to the front buffer, the rendering

    * that will happen next will probably dirty the front buffer.  So

    * mark it as dirty here.

    */

   if (intel->is_front_buffer_rendering)

      intel->front_buffer_dirty = true;

   /* Wait for the swapbuffers before the one we just emitted, so we

    * don't get too many swaps outstanding for apps that are GPU-heavy

    * but not CPU-heavy.

    *

    * We're using intelDRI2Flush (called from the loader before

    * swapbuffer) and glFlush (for front buffer rendering) as the

    * indicator that a frame is done and then throttle when we get

    * here as we prepare to render the next frame.  At this point for

    * round trips for swap/copy and getting new buffers are done and

    * we'll spend less time waiting on the GPU.

    *

    * Unfortunately, we don't have a handle to the batch containing

    * the swap, and getting our hands on that doesn't seem worth it,

    * so we just us the first batch we emitted after the last swap.

    */

   if (intel->need_throttle && intel->first_post_swapbuffers_batch) {

      if (!intel->disable_throttling)

         drm_intel_bo_wait_rendering(intel->first_post_swapbuffers_batch);

      drm_intel_bo_unreference(intel->first_post_swapbuffers_batch);

      intel->first_post_swapbuffers_batch = NULL;

      intel->need_throttle = false;

   }

}

static void

intel_viewport(struct gl_context *ctx, GLint x, GLint y, GLsizei w, GLsizei h)

{

    struct intel_context *intel = intel_context(ctx);

    __DRIcontext *driContext = intel->driContext;

    if (intel->saved_viewport)

	intel->saved_viewport(ctx, x, y, w, h);

    if (_mesa_is_winsys_fbo(ctx->DrawBuffer)) {

       dri2InvalidateDrawable(driContext->driDrawablePriv);

       dri2InvalidateDrawable(driContext->driReadablePriv);

    }

}

static const struct dri_debug_control debug_control[] = {

   { "tex",   DEBUG_TEXTURE},

   { "state", DEBUG_STATE},

   { "blit",  DEBUG_BLIT},

   { "mip",   DEBUG_MIPTREE},

   { "fall",  DEBUG_PERF},

   { "perf",  DEBUG_PERF},

   { "bat",   DEBUG_BATCH},

   { "pix",   DEBUG_PIXEL},

   { "buf",   DEBUG_BUFMGR},

   { "reg",   DEBUG_REGION},

   { "fbo",   DEBUG_FBO},

   { "fs",    DEBUG_WM },

   { "sync",  DEBUG_SYNC},

   { "dri",   DEBUG_DRI },

   { "stats", DEBUG_STATS },

   { "wm",    DEBUG_WM },

   { "aub",   DEBUG_AUB },

   { NULL,    0 }

};

static void

intelInvalidateState(struct gl_context * ctx, GLuint new_state)

{

    struct intel_context *intel = intel_context(ctx);

    if (ctx->swrast_context)

       _swrast_InvalidateState(ctx, new_state);

   _vbo_InvalidateState(ctx, new_state);

   intel->NewGLState |= new_state;

   if (intel->vtbl.invalidate_state)

      intel->vtbl.invalidate_state( intel, new_state );

}

void

intel_flush_rendering_to_batch(struct gl_context *ctx)

{

   struct intel_context *intel = intel_context(ctx);

   if (intel->Fallback)

      _swrast_flush(ctx);

   INTEL_FIREVERTICES(intel);

}

void

_intel_flush(struct gl_context *ctx, const char *file, int line)

{

   struct intel_context *intel = intel_context(ctx);

   intel_flush_rendering_to_batch(ctx);

   if (intel->batch.used)

      _intel_batchbuffer_flush(intel, file, line);

}

static void

intel_glFlush(struct gl_context *ctx)

{

   struct intel_context *intel = intel_context(ctx);

   intel_flush(ctx);

   intel_flush_front(ctx);

   if (intel->is_front_buffer_rendering)

      intel->need_throttle = true;

}

void

intelFinish(struct gl_context * ctx)

{

   struct intel_context *intel = intel_context(ctx);

   intel_flush(ctx);

   intel_flush_front(ctx);

   if (intel->batch.last_bo)

      drm_intel_bo_wait_rendering(intel->batch.last_bo);

}

void

intelInitDriverFunctions(struct dd_function_table *functions)

{

   _mesa_init_driver_functions(functions);

   functions->Flush = intel_glFlush;

   functions->Finish = intelFinish;

   functions->GetString = intelGetString;

   functions->UpdateState = intelInvalidateState;

   intelInitTextureFuncs(functions);

   intelInitTextureImageFuncs(functions);

   intelInitTextureSubImageFuncs(functions);

   intelInitTextureCopyImageFuncs(functions);

   intelInitClearFuncs(functions);

   intelInitBufferFuncs(functions);

   intelInitPixelFuncs(functions);

   intelInitBufferObjectFuncs(functions);

   intel_init_syncobj_functions(functions);

}

static bool

validate_context_version(struct intel_screen *screen,

                         int mesa_api,

                         unsigned major_version,

                         unsigned minor_version,

                         unsigned *dri_ctx_error)

{

   unsigned req_version = 10 * major_version + minor_version;

   unsigned max_version = 0;

   switch (mesa_api) {

   case API_OPENGL_COMPAT:

      max_version = screen->max_gl_compat_version;

      break;

   case API_OPENGL_CORE:

      max_version = screen->max_gl_core_version;

      break;

   case API_OPENGLES:

      max_version = screen->max_gl_es1_version;

      break;

   case API_OPENGLES2:

      max_version = screen->max_gl_es2_version;

      break;

   default:

      max_version = 0;

      break;

   }

   if (max_version == 0) {

      *dri_ctx_error = __DRI_CTX_ERROR_BAD_API;

      return false;

   } else if (req_version > max_version) {

      *dri_ctx_error = __DRI_CTX_ERROR_BAD_VERSION;

      return false;

   }

   return true;

}

bool

intelInitContext(struct intel_context *intel,

                 int api,

                 unsigned major_version,

                 unsigned minor_version,

                 const struct gl_config * mesaVis,

                 __DRIcontext * driContextPriv,

                 void *sharedContextPrivate,

                 struct dd_function_table *functions,

                 unsigned *dri_ctx_error)

{

   struct gl_context *ctx = &intel->ctx;

   struct gl_context *shareCtx = (struct gl_context *) sharedContextPrivate;

   __DRIscreen *sPriv = driContextPriv->driScreenPriv;

   struct intel_screen *intelScreen = sPriv->driverPrivate;

   int bo_reuse_mode;

   struct gl_config visual;

   /* we can't do anything without a connection to the device */

   if (intelScreen->bufmgr == NULL) {

      *dri_ctx_error = __DRI_CTX_ERROR_NO_MEMORY;

      return false;

   }

   if (!validate_context_version(intelScreen,

                                 api, major_version, minor_version,

                                 dri_ctx_error))

      return false;

   /* Can't rely on invalidate events, fall back to glViewport hack */

   if (!driContextPriv->driScreenPriv->dri2.useInvalidate) {

      intel->saved_viewport = functions->Viewport;

      functions->Viewport = intel_viewport;

   }

   if (mesaVis == NULL) {

      memset(&visual, 0, sizeof visual);

      mesaVis = &visual;

   }

   intel->intelScreen = intelScreen;

   if (!_mesa_initialize_context(&intel->ctx, api, mesaVis, shareCtx,

                                 functions)) {

      *dri_ctx_error = __DRI_CTX_ERROR_NO_MEMORY;

      printf("%s: failed to init mesa context\n", __FUNCTION__);

      return false;

   }

   driContextPriv->driverPrivate = intel;

   intel->driContext = driContextPriv;

   intel->driFd = sPriv->fd;

   intel->gen = intelScreen->gen;

   const int devID = intelScreen->deviceID;

   intel->is_945 = IS_945(devID);

   intel->has_swizzling = intel->intelScreen->hw_has_swizzling;

   memset(&ctx->TextureFormatSupported,

	  0, sizeof(ctx->TextureFormatSupported));

   driParseConfigFiles(&intel->optionCache, &intelScreen->optionCache,

                       sPriv->myNum, "i915");

   intel->maxBatchSize = 4096;

   /* Estimate the size of the mappable aperture into the GTT.  There's an

    * ioctl to get the whole GTT size, but not one to get the mappable subset.

    * It turns out it's basically always 256MB, though some ancient hardware

    * was smaller.

    */

   uint32_t gtt_size = 256 * 1024 * 1024;

   if (intel->gen == 2)

      gtt_size = 128 * 1024 * 1024;

   /* We don't want to map two objects such that a memcpy between them would

    * just fault one mapping in and then the other over and over forever.  So

    * we would need to divide the GTT size by 2.  Additionally, some GTT is

    * taken up by things like the framebuffer and the ringbuffer and such, so

    * be more conservative.

    */

   intel->max_gtt_map_object_size = gtt_size / 4;

   intel->bufmgr = intelScreen->bufmgr;

   bo_reuse_mode = driQueryOptioni(&intel->optionCache, "bo_reuse");

   switch (bo_reuse_mode) {

   case DRI_CONF_BO_REUSE_DISABLED:

      break;

   case DRI_CONF_BO_REUSE_ALL:

      intel_bufmgr_gem_enable_reuse(intel->bufmgr);

      break;

   }

   ctx->Const.MinLineWidth = 1.0;

   ctx->Const.MinLineWidthAA = 1.0;

   ctx->Const.MaxLineWidth = 5.0;

   ctx->Const.MaxLineWidthAA = 5.0;

   ctx->Const.LineWidthGranularity = 0.5;

   ctx->Const.MinPointSize = 1.0;

   ctx->Const.MinPointSizeAA = 1.0;

   ctx->Const.MaxPointSize = 255.0;

   ctx->Const.MaxPointSizeAA = 3.0;

   ctx->Const.PointSizeGranularity = 1.0;

   ctx->Const.StripTextureBorder = GL_TRUE;

   /* reinitialize the context point state.

    * It depend on constants in __struct gl_contextRec::Const

    */

   _mesa_init_point(ctx);

   ctx->Const.MaxRenderbufferSize = 2048;

   _swrast_CreateContext(ctx);

   _vbo_CreateContext(ctx);

   if (ctx->swrast_context) {

      _tnl_CreateContext(ctx);

      _swsetup_CreateContext(ctx);

      /* Configure swrast to match hardware characteristics: */

      _swrast_allow_pixel_fog(ctx, false);

      _swrast_allow_vertex_fog(ctx, true);

   }

   _mesa_meta_init(ctx);

   intel->hw_stencil = mesaVis->stencilBits && mesaVis->depthBits == 24;

   intel->hw_stipple = 1;

   intel->RenderIndex = ~0;

   intelInitExtensions(ctx);

   INTEL_DEBUG = driParseDebugString(getenv("INTEL_DEBUG"), debug_control);

   if (INTEL_DEBUG & DEBUG_BUFMGR)

      dri_bufmgr_set_debug(intel->bufmgr, true);

   if (INTEL_DEBUG & DEBUG_PERF)

      intel->perf_debug = true;

   if (INTEL_DEBUG & DEBUG_AUB)

      drm_intel_bufmgr_gem_set_aub_dump(intel->bufmgr, true);

   intel_batchbuffer_init(intel);

   intel_fbo_init(intel);

   intel->use_early_z = driQueryOptionb(&intel->optionCache, "early_z");

   intel->prim.primitive = ~0;

   /* Force all software fallbacks */

   if (driQueryOptionb(&intel->optionCache, "no_rast")) {

      fprintf(stderr, "disabling 3D rasterization\n");

      intel->no_rast = 1;

   }

   if (driQueryOptionb(&intel->optionCache, "always_flush_batch")) {

      fprintf(stderr, "flushing batchbuffer before/after each draw call\n");

      intel->always_flush_batch = 1;

   }

   if (driQueryOptionb(&intel->optionCache, "always_flush_cache")) {

      fprintf(stderr, "flushing GPU caches before/after each draw call\n");

      intel->always_flush_cache = 1;

   }

   if (driQueryOptionb(&intel->optionCache, "disable_throttling")) {

      fprintf(stderr, "disabling flush throttling\n");

      intel->disable_throttling = 1;

   }

   return true;

}

void

intelDestroyContext(__DRIcontext * driContextPriv)

{

   struct intel_context *intel =

      (struct intel_context *) driContextPriv->driverPrivate;

   struct gl_context *ctx = &intel->ctx;

   assert(intel);               /* should never be null */

   if (intel) {

      INTEL_FIREVERTICES(intel);

      /* Dump a final BMP in case the application doesn't call SwapBuffers */

      if (INTEL_DEBUG & DEBUG_AUB) {

         intel_batchbuffer_flush(intel);

	 aub_dump_bmp(&intel->ctx);

      }

      _mesa_meta_free(&intel->ctx);

      intel->vtbl.destroy(intel);

      if (ctx->swrast_context) {

         _swsetup_DestroyContext(&intel->ctx);

         _tnl_DestroyContext(&intel->ctx);

      }

      _vbo_DestroyContext(&intel->ctx);

      if (ctx->swrast_context)

         _swrast_DestroyContext(&intel->ctx);

      intel->Fallback = 0x0;      /* don't call _swrast_Flush later */

      intel_batchbuffer_free(intel);

      free(intel->prim.vb);

      intel->prim.vb = NULL;

      drm_intel_bo_unreference(intel->prim.vb_bo);

      intel->prim.vb_bo = NULL;

      drm_intel_bo_unreference(intel->first_post_swapbuffers_batch);

      intel->first_post_swapbuffers_batch = NULL;

      driDestroyOptionCache(&intel->optionCache);

      /* free the Mesa context */

      _mesa_free_context_data(&intel->ctx);

      _math_matrix_dtr(&intel->ViewportMatrix);

      ralloc_free(intel);

      driContextPriv->driverPrivate = NULL;

   }

}

GLboolean

intelUnbindContext(__DRIcontext * driContextPriv)

{

   /* Unset current context and dispath table */

   _mesa_make_current(NULL, NULL, NULL);

   return true;

}

GLboolean

intelMakeCurrent(__DRIcontext * driContextPriv,

                 __DRIdrawable * driDrawPriv,

                 __DRIdrawable * driReadPriv)

{

   struct intel_context *intel;

   GET_CURRENT_CONTEXT(curCtx);

   if (driContextPriv)

      intel = (struct intel_context *) driContextPriv->driverPrivate;

   else

      intel = NULL;

   /* According to the glXMakeCurrent() man page: "Pending commands to

    * the previous context, if any, are flushed before it is released."

    * But only flush if we're actually changing contexts.

    */

   if (intel_context(curCtx) && intel_context(curCtx) != intel) {

      _mesa_flush(curCtx);

   }

   if (driContextPriv) {

      struct gl_context *ctx = &intel->ctx;

      struct gl_framebuffer *fb, *readFb;

      if (driDrawPriv == NULL && driReadPriv == NULL) {

	 fb = _mesa_get_incomplete_framebuffer();

	 readFb = _mesa_get_incomplete_framebuffer();

      } else {

	 fb = driDrawPriv->driverPrivate;

	 readFb = driReadPriv->driverPrivate;

	 driContextPriv->dri2.draw_stamp = driDrawPriv->dri2.stamp - 1;

	 driContextPriv->dri2.read_stamp = driReadPriv->dri2.stamp - 1;

      }

      intel_prepare_render(intel);

      _mesa_make_current(ctx, fb, readFb);

      /* We do this in intel_prepare_render() too, but intel->ctx.DrawBuffer

       * is NULL at that point.  We can't call _mesa_makecurrent()

       * first, since we need the buffer size for the initial

       * viewport.  So just call intel_draw_buffer() again here. */

      intel_draw_buffer(ctx);

   }

   else {

      _mesa_make_current(NULL, NULL, NULL);

   }

   return true;

}

/**

 * \brief Query DRI2 to obtain a DRIdrawable's buffers.

 *

 * To determine which DRI buffers to request, examine the renderbuffers

 * attached to the drawable's framebuffer. Then request the buffers with

 * DRI2GetBuffers() or DRI2GetBuffersWithFormat().

 *

 * This is called from intel_update_renderbuffers().

 *

 * \param drawable      Drawable whose buffers are queried.

 * \param buffers       [out] List of buffers returned by DRI2 query.

 * \param buffer_count  [out] Number of buffers returned.

 *

 * \see intel_update_renderbuffers()

 * \see DRI2GetBuffers()

 * \see DRI2GetBuffersWithFormat()

 */

static void

intel_query_dri2_buffers(struct intel_context *intel,

			 __DRIdrawable *drawable,

			 __DRIbuffer **buffers,

			 int *buffer_count)

{

   __DRIscreen *screen = intel->intelScreen->driScrnPriv;

   struct gl_framebuffer *fb = drawable->driverPrivate;

   int i = 0;

   unsigned attachments[8];

   struct intel_renderbuffer *front_rb;

   struct intel_renderbuffer *back_rb;

   front_rb = intel_get_renderbuffer(fb, BUFFER_FRONT_LEFT);

   back_rb = intel_get_renderbuffer(fb, BUFFER_BACK_LEFT);

   memset(attachments, 0, sizeof(attachments));

   if ((intel->is_front_buffer_rendering ||

	intel->is_front_buffer_reading ||

	!back_rb) && front_rb) {

      /* If a fake front buffer is in use, then querying for

       * __DRI_BUFFER_FRONT_LEFT will cause the server to copy the image from

       * the real front buffer to the fake front buffer.  So before doing the

       * query, we need to make sure all the pending drawing has landed in the

       * real front buffer.

       */

      intel_flush(&intel->ctx);

      intel_flush_front(&intel->ctx);

      attachments[i++] = __DRI_BUFFER_FRONT_LEFT;

      attachments[i++] = intel_bits_per_pixel(front_rb);

   } else if (front_rb && intel->front_buffer_dirty) {

      /* We have pending front buffer rendering, but we aren't querying for a

       * front buffer.  If the front buffer we have is a fake front buffer,

       * the X server is going to throw it away when it processes the query.

       * So before doing the query, make sure all the pending drawing has

       * landed in the real front buffer.

       */

      intel_flush(&intel->ctx);

      intel_flush_front(&intel->ctx);

   }

   if (back_rb) {

      attachments[i++] = __DRI_BUFFER_BACK_LEFT;

      attachments[i++] = intel_bits_per_pixel(back_rb);

   }

   assert(i <= ARRAY_SIZE(attachments));

   *buffers = screen->dri2.loader->getBuffersWithFormat(drawable,

							&drawable->w,

							&drawable->h,

							attachments, i / 2,

							buffer_count,

							drawable->loaderPrivate);

}

/**

 * \brief Assign a DRI buffer's DRM region to a renderbuffer.

 *

 * This is called from intel_update_renderbuffers().

 *

 * \par Note:

 *    DRI buffers whose attachment point is DRI2BufferStencil or

 *    DRI2BufferDepthStencil are handled as special cases.

 *

 * \param buffer_name is a human readable name, such as "dri2 front buffer",

 *        that is passed to intel_region_alloc_for_handle().

 *

 * \see intel_update_renderbuffers()

 * \see intel_region_alloc_for_handle()

 */

static void

intel_process_dri2_buffer(struct intel_context *intel,

			  __DRIdrawable *drawable,

			  __DRIbuffer *buffer,

			  struct intel_renderbuffer *rb,

			  const char *buffer_name)

{

   struct intel_region *region = NULL;

   if (!rb)

      return;

   /* We try to avoid closing and reopening the same BO name, because the first

    * use of a mapping of the buffer involves a bunch of page faulting which is

    * moderately expensive.

    */

   if (rb->mt &&

       rb->mt->region &&

       rb->mt->region->name == buffer->name)

      return;

   if (unlikely(INTEL_DEBUG & DEBUG_DRI)) {

      fprintf(stderr,

	      "attaching buffer %d, at %d, cpp %d, pitch %d\n",

	      buffer->name, buffer->attachment,

	      buffer->cpp, buffer->pitch);

   }

   intel_miptree_release(&rb->mt);

   region = intel_region_alloc_for_handle(intel->intelScreen,

                                          buffer->cpp,

                                          drawable->w,

                                          drawable->h,

                                          buffer->pitch,

                                          buffer->name,

                                          buffer_name);

   if (!region)

      return;

   rb->mt = intel_miptree_create_for_dri2_buffer(intel,

                                                 buffer->attachment,

                                                 intel_rb_format(rb),

                                                 region);

   intel_region_release(®ion);

}