zero copy - NOT FOR REVIEW

content/browser/gpu/browser_gpu_channel_host_factory.cc

Index: content/browser/gpu/browser_gpu_channel_host_factory.cc
diff --git a/content/browser/gpu/browser_gpu_channel_host_factory.cc b/content/browser/gpu/browser_gpu_channel_host_factory.cc
index 075c8f993f5da2332a185895ee210b8e68d8155c..7d62ac074be7ddfca2ba322c4000f41433c8118f 100644
--- a/content/browser/gpu/browser_gpu_channel_host_factory.cc
+++ b/content/browser/gpu/browser_gpu_channel_host_factory.cc
@@ -11,12 +11,154 @@
 #include "content/browser/gpu/gpu_process_host.h"
 #include "content/browser/gpu/gpu_surface_tracker.h"
 #include "content/common/child_process_host_impl.h"
+#include "content/common/gpu/client/gpu_memory_buffer_impl_foobar.h"
 #include "content/common/gpu/client/gpu_memory_buffer_impl_shm.h"
 #include "content/common/gpu/gpu_messages.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/gpu_data_manager.h"
 #include "content/public/common/content_client.h"
 #include "ipc/ipc_forwarding_message_filter.h"
+#include "ui/gfx/x/x11_types.h"
+
+extern char GetZCopy();
+
+namespace foobar {
+
+extern "C" {
+#include <fcntl.h>
+#include <libdrm/i915_drm.h>
+#include <libdrm/intel_bufmgr.h>
+#include <xf86drm.h>
+#include <X11/Xlib.h>
+#include <X11/Xlibint.h>
+#include <X11/extensions/Xext.h>
+#include <X11/extensions/extutil.h>
+#include <X11/extensions/dri2proto.h>
+}
+
+static char dri2ExtensionName[] = DRI2_NAME;
+static XExtensionInfo *dri2Info;
+
+static /* const */ XExtensionHooks dri2ExtensionHooks = {
+  NULL, /* create_gc */
+  NULL, /* copy_gc */
+  NULL, /* flush_gc */
+  NULL, /* free_gc */
+  NULL, /* create_font */
+  NULL, /* free_font */
+  NULL, /* close_display */
+  NULL, /* wire_to_event */
+  NULL, /* event_to_wire */
+  NULL, /* error */
+  NULL, /* error_string */
+};
+
+static XEXT_GENERATE_FIND_DISPLAY (DRI2FindDisplay,
+                                   dri2Info,
+                                   dri2ExtensionName,
+                                   &dri2ExtensionHooks,
+                                   0, NULL)
+
+static int dri_fd = -1;
+static drm_intel_bufmgr *bufmgr = NULL;
+
+static Bool OpenDri() {
+  if (bufmgr) return True;
+
+  dri_fd = open("/dev/dri/card0", O_RDWR);
+  if (dri_fd < 0) {
+    TRACE_EVENT_INSTANT0("zcopy", "open dri device failed",
+                         TRACE_EVENT_SCOPE_THREAD);
+    return False;
+  }
+
+  drm_magic_t magic;
+  if (drmGetMagic(dri_fd, &magic)) {
+    close(dri_fd);
+    TRACE_EVENT_INSTANT0("zcopy", "drmGetMagic failed",
+                         TRACE_EVENT_SCOPE_THREAD);
+    return False;
+  }
+
+  Display *dpy = (Display *) gfx::GetXDisplay();
+  XExtDisplayInfo *info = DRI2FindDisplay(dpy);
+  xDRI2AuthenticateReq *req;
+  xDRI2AuthenticateReply rep;
+
+  XextCheckExtension(dpy, info, dri2ExtensionName, False);
+
+  LockDisplay(dpy);
+  GetReq(DRI2Authenticate, req);
+  req->reqType = info->codes->major_opcode;
+  req->dri2ReqType = X_DRI2Authenticate;
+  req->window = DefaultRootWindow(dpy);
+  req->magic = magic;
+
+  if (!_XReply(dpy, (xReply *) &rep, 0, xFalse)) {
+    dri_fd = -1;
+  }
+  UnlockDisplay(dpy);
+  SyncHandle();
+
+  if (dri_fd < 0 || !rep.authenticated) {
+    close(dri_fd);
+    TRACE_EVENT_INSTANT0("zcopy", "authentication failed",
+                         TRACE_EVENT_SCOPE_THREAD);
+  } else {
+    bufmgr = drm_intel_bufmgr_gem_init(dri_fd, 2048); //XXX what is this number?
+    if (!bufmgr) {
+      TRACE_EVENT_INSTANT0("zcopy", "gem_init failed",
+                           TRACE_EVENT_SCOPE_THREAD);
+    }
+  }
+
+  return bufmgr != NULL;
+}
+
+static void *AllocTexture(unsigned width, unsigned height, unsigned bpp) {
+  // Figuring out how much memory to allocate for a texture is pretty
+  // complicated due to padding and alignment concerns, and mipmaps, to
+  // name a few reasons.
+  // There's a lot of logic in the mesa i965 driver to handle it, which
+  // is one of the drawbacks to allocating the texture memory here.
+  // The checks here will catch some problems, but maybe not all.
+  uint32_t tiling, want;
+  unsigned long pitch;
+
+  if ((width % 4) || (height % 2)) {
+    TRACE_EVENT_INSTANT2("zcopy", "can't handle texure size",
+                         TRACE_EVENT_SCOPE_THREAD,
+                         "width", width,
+                         "height", height);
+    return NULL;
+  }
+
+  tiling = want = GetZCopy() == 'u' ? I915_TILING_NONE : I915_TILING_Y;
+  drm_intel_bo *bo = drm_intel_bo_alloc_tiled(bufmgr, "region", width, height,
+                                              bpp, &tiling, &pitch, 0);
+
+  if (tiling != want) {
+    TRACE_EVENT_INSTANT2("zcopy", "did not get requested tiling",
+                         TRACE_EVENT_SCOPE_THREAD,
+                         "width", width,
+                         "height", height);
+    drm_intel_bo_unreference(bo);
+    return NULL;
+  }
+
+  if (pitch != width * 4) {
+    TRACE_EVENT_INSTANT2("zcopy", "did not get expected pitch",
+                         TRACE_EVENT_SCOPE_THREAD,
+                         "width", width,
+                         "height", height);
+    drm_intel_bo_unreference(bo);
+    return NULL;
+  }
+
+  return bo;
+}
+
+} // namespace foobar
 
 namespace content {
 
@@ -379,6 +521,27 @@ scoped_ptr<gfx::GpuMemoryBuffer>
   if (!GpuMemoryBufferImpl::IsFormatValid(internalformat))
     return scoped_ptr<gfx::GpuMemoryBuffer>();
 
+#if defined(OS_LINUX) || defined(OS_CHROMEOS)
+  if (GetZCopy()) {
+    if (!GpuMemoryBufferImplFoobar::IsFormatSupported(internalformat)) {
+      TRACE_EVENT_INSTANT0("zcopy", "can't handle texure format",
+                           TRACE_EVENT_SCOPE_THREAD);
+    } else if (foobar::OpenDri()) {
+      // This object needs to be created somehow. Can be something
+      // platform/driver specific.
+      void *foobar_object = foobar::AllocTexture(width, height,
+          GpuMemoryBufferImpl::BytesPerPixel(internalformat));
+      if (foobar_object) {
+        scoped_ptr<GpuMemoryBufferImplFoobar> foobar_buffer(
+            new GpuMemoryBufferImplFoobar(gfx::Size(width, height),
+                                          internalformat));
+        if (foobar_buffer->InitializeFromFoobarObject(foobar_object))
+          return foobar_buffer.PassAs<gfx::GpuMemoryBuffer>();
+      }
+    }
+  }
+#endif
+
   size_t size = width * height *
       GpuMemoryBufferImpl::BytesPerPixel(internalformat);
   scoped_ptr<base::SharedMemory> shm(new base::SharedMemory());