dix: introduce gpu screens. (v5)

This patch introduces gpu screens into screenInfo. It adds interfaces
for adding and removing gpu screens, along with adding private fixup,
block handler support, and scratch pixmap init.

GPU screens have a myNum that is offset by GPU_SCREEN_OFFSET (256),
this is used for logging etc.

RemoveGPUScreen isn't used until "xfree86: add platform bus hotplug support".

v2: no glyph pictures for GPU screens for now.
v3: introduce MAXGPUSCREENS, fix return value check
v4: fixup myNum when renumbering screens (ajax)
v5: drop cursor privates for now.

Reviewed-by: Keith Packard <keithp@keithp.com>
Signed-off-by: Dave Airlie <airlied@redhat.com>

dix/dispatch.c

@@ -3724,7 +3724,7 @@ with its screen number, a pointer to its ScreenRec, argc, and argv.
 
 */
 
-static int init_screen(ScreenPtr pScreen, int i)
+static int init_screen(ScreenPtr pScreen, int i, Bool gpu)
 {
     int scanlinepad, format, depth, bitsPerPixel, j, k;
 
@@ -3734,6 +3734,10 @@ static int init_screen(ScreenPtr pScreen, int i)
         return -1;
     }
     pScreen->myNum = i;
+    if (gpu) {
+        pScreen->myNum += GPU_SCREEN_OFFSET;
+        pScreen->isGPU = TRUE;
+    }
     pScreen->totalPixmapSize = 0;       /* computed in CreateScratchPixmapForScreen */
     pScreen->ClipNotify = 0;    /* for R4 ddx compatibility */
     pScreen->CreateScreenResources = 0;
@@ -3790,7 +3794,7 @@ AddScreen(Bool (*pfnInit) (ScreenPtr /*pScreen */ ,
     if (!pScreen)
         return -1;
 
-    ret = init_screen(pScreen, i);
+    ret = init_screen(pScreen, i, FALSE);
     if (ret != 0) {
         free(pScreen);
         return ret;
@@ -3820,3 +3824,68 @@ AddScreen(Bool (*pfnInit) (ScreenPtr /*pScreen */ ,
 
     return i;
 }
+
+int
+AddGPUScreen(Bool (*pfnInit) (ScreenPtr /*pScreen */ ,
+                              int /*argc */ ,
+                              char **      /*argv */
+                              ),
+             int argc, char **argv)
+{
+    int i;
+    ScreenPtr pScreen;
+    Bool ret;
+
+    i = screenInfo.numGPUScreens;
+    if (i == MAXGPUSCREENS)
+        return -1;
+
+    pScreen = (ScreenPtr) calloc(1, sizeof(ScreenRec));
+    if (!pScreen)
+        return -1;
+
+    ret = init_screen(pScreen, i, TRUE);
+    if (ret != 0) {
+        free(pScreen);
+        return ret;
+    }
+
+    /* This is where screen specific stuff gets initialized.  Load the
+       screen structure, call the hardware, whatever.
+       This is also where the default colormap should be allocated and
+       also pixel values for blackPixel, whitePixel, and the cursor
+       Note that InitScreen is NOT allowed to modify argc, argv, or
+       any of the strings pointed to by argv.  They may be passed to
+       multiple screens.
+     */
+    screenInfo.gpuscreens[i] = pScreen;
+    screenInfo.numGPUScreens++;
+    if (!(*pfnInit) (pScreen, argc, argv)) {
+        dixFreePrivates(pScreen->devPrivates, PRIVATE_SCREEN);
+        free(pScreen);
+        screenInfo.numGPUScreens--;
+        return -1;
+    }
+
+    update_desktop_dimensions();
+
+    return i;
+}
+
+void
+RemoveGPUScreen(ScreenPtr pScreen)
+{
+    int idx, j;
+    if (!pScreen->isGPU)
+        return;
+
+    idx = pScreen->myNum - GPU_SCREEN_OFFSET;
+    for (j = idx; j < screenInfo.numGPUScreens - 1; j++) {
+        screenInfo.gpuscreens[j] = screenInfo.gpuscreens[j + 1];
+        screenInfo.gpuscreens[j]->myNum = j + GPU_SCREEN_OFFSET;
+    }
+    screenInfo.numGPUScreens--;
+
+    free(pScreen);
+
+}

dix/dixutils.c

@@ -386,6 +386,9 @@ BlockHandler(pointer pTimeout, pointer pReadmask)
     for (i = 0; i < screenInfo.numScreens; i++)
         (*screenInfo.screens[i]->BlockHandler) (screenInfo.screens[i],
                                                 pTimeout, pReadmask);
+    for (i = 0; i < screenInfo.numGPUScreens; i++)
+        (*screenInfo.gpuscreens[i]->BlockHandler) (screenInfo.gpuscreens[i],
+                                                   pTimeout, pReadmask);
     for (i = 0; i < numHandlers; i++)
         if (!handlers[i].deleted)
             (*handlers[i].BlockHandler) (handlers[i].blockData,
@@ -422,6 +425,9 @@ WakeupHandler(int result, pointer pReadmask)
     for (i = 0; i < screenInfo.numScreens; i++)
         (*screenInfo.screens[i]->WakeupHandler) (screenInfo.screens[i],
                                                  result, pReadmask);
+    for (i = 0; i < screenInfo.numGPUScreens; i++)
+        (*screenInfo.gpuscreens[i]->WakeupHandler) (screenInfo.gpuscreens[i],
+                                                    result, pReadmask);
     if (handlerDeleted) {
         for (i = 0; i < numHandlers;)
             if (handlers[i].deleted) {

dix/main.c

@@ -207,6 +207,12 @@ main(int argc, char *argv[], char *envp[])
             FatalError("no screens found");
         InitExtensions(argc, argv);
 
+        for (i = 0; i < screenInfo.numGPUScreens; i++) {
+            ScreenPtr pScreen = screenInfo.gpuscreens[i];
+            if (!CreateScratchPixmapsForScreen(pScreen))
+                FatalError("failed to create scratch pixmaps");
+        }
+
         for (i = 0; i < screenInfo.numScreens; i++) {
             ScreenPtr pScreen = screenInfo.screens[i];
 
@@ -336,6 +342,15 @@ main(int argc, char *argv[], char *envp[])
             screenInfo.numScreens = i;
         }
 
+        for (i = screenInfo.numGPUScreens - 1; i >= 0; i--) {
+            ScreenPtr pScreen = screenInfo.gpuscreens[i];
+            FreeScratchPixmapsForScreen(pScreen);
+            (*pScreen->CloseScreen) (pScreen);
+            dixFreePrivates(pScreen->devPrivates, PRIVATE_SCREEN);
+            free(pScreen);
+            screenInfo.numGPUScreens = i;
+        }
+
         ReleaseClientIds(serverClient);
         dixFreePrivates(serverClient->devPrivates, PRIVATE_CLIENT);
         serverClient->devPrivates = NULL;

dix/privates.c

@@ -222,6 +222,10 @@ fixupScreens(FixupFunc fixup, unsigned bytes)
     for (s = 0; s < screenInfo.numScreens; s++)
         if (!fixupOneScreen (screenInfo.screens[s], fixup, bytes))
             return FALSE;
+
+    for (s = 0; s < screenInfo.numGPUScreens; s++)
+        if (!fixupOneScreen (screenInfo.gpuscreens[s], fixup, bytes))
+            return FALSE;
     return TRUE;
 }