Changeset 95461 in vbox for trunk/src/VBox/Devices/Graphics

Timestamp:

Jun 30, 2022 12:56:31 PM (3 years ago)

Author:

vboxsync

Message:

DevVGA: Fixed problem with VBE banking destroying MMIO2 remapping optimization (see bugref:10251).

Location:

trunk/src/VBox/Devices/Graphics

Files:

• DevVGA.cpp (modified) (13 diffs)
• DevVGA.h (modified) (2 diffs)

trunk/src/VBox/Devices/Graphics/DevVGA.cpp

@@ -301 +301 @@
 
 /**
+ * Mark a page in VGA A0000-AFFFF range as remapped.
+ *
+ * @param   pThis       VGA instance data.
+ * @param   offVGAMem   The offset within VGA memory.
+ */
+DECLINLINE(void) vgaMarkRemapped(PVGASTATE pThis, RTGCPHYS offVGAMem)
+{
+    AssertMsg(offVGAMem < _64K, ("offVGAMem = %p > 64K\n", offVGAMem));
+    ASMBitSet(&pThis->bmPageMapBitmap, offVGAMem >> GUEST_PAGE_SHIFT);
+    pThis->fRemappedVGA = true;
+}
+
+/**
+ * Checks if a page in VGA A0000-AFFFF range is remapped.
+ *
+ * @returns true if remapped.
+ * @returns false if not remapped (accesses will trap).
+ * @param   pThis       VGA instance data.
+ * @param   offVGAMem   The offset within VGA memory.
+ */
+DECLINLINE(bool) vgaIsRemapped(PVGASTATE pThis, RTGCPHYS offVGAMem)
+{
+    AssertMsg(offVGAMem < _64K, ("offVGAMem = %p > 64K\n", offVGAMem));
+    return ASMBitTest(&pThis->bmPageMapBitmap, offVGAMem >> GUEST_PAGE_SHIFT);
+}
+
+/**
+ * Reset page remap tracking bits.
+ *
+ * @param   pThis           VGA instance data.
+ */
+DECLINLINE(void) vgaResetRemapped(PVGASTATE pThis)
+{
+    pThis->fRemappedVGA = false;
+    ASMBitClearRange(&pThis->bmPageMapBitmap, 0, _64K >> GUEST_PAGE_SHIFT);
+}
+
+/**
  * Set a VRAM page dirty.
  *
@@ -699 +737 @@
             {
                 PDMDevHlpMmioResetRegion(pDevIns, pThis->hMmioLegacy);
-                pThis->fRemappedVGA = false;
+                vgaResetRemapped(pThis);
             }
         }
@@ -738 +776 @@
             {
                 PDMDevHlpMmioResetRegion(pDevIns, pThis->hMmioLegacy);
-                pThis->fRemappedVGA = false;
+                vgaResetRemapped(pThis);
             }
         }
@@ -996 +1034 @@
             {
                 PDMDevHlpMmioResetRegion(pDevIns, pThis->hMmioLegacy);
-                pThis->fRemappedVGA = false;
+                vgaResetRemapped(pThis);
             }
 # endif
@@ -1105 +1143 @@
             {
                 PDMDevHlpMmioResetRegion(pDevIns, pThis->hMmioLegacy);
-                pThis->fRemappedVGA = false;
+                vgaResetRemapped(pThis);
             }
             break;
@@ -1200 +1238 @@
         /* If all planes are accessible, then map the page to the frame buffer and make it writable. */
         if (   (pThis->sr[2] & 3) == 3
-            && !vgaIsDirty(pThis, addr)
+            && !vgaIsRemapped(pThis, GCPhys - 0xa0000)
             && pThis->GCPhysVRAM)
         {
@@ -1209 +1247 @@
             /* Set as dirty as write accesses won't be noticed now. */
             vgaR3MarkDirty(pThis, addr);
-            pThis->fRemappedVGA = true;
+            vgaMarkRemapped(pThis, GCPhys - 0xa0000);
         }
 #endif /* !IN_RC */
@@ -1309 +1347 @@
             /* If all planes are accessible, then map the page to the frame buffer and make it writable. */
             if (   (pThis->sr[2] & 3) == 3
-                && !vgaIsDirty(pThis, addr)
+                && !vgaIsRemapped(pThis, GCPhys - 0xa0000)
                 && pThis->GCPhysVRAM)
             {
@@ -1315 +1353 @@
                 PDMDevHlpMmioMapMmio2Page(pDevIns, pThis->hMmioLegacy, GCPhys - 0xa0000,
                                           pThis->hMmio2VRam, addr, X86_PTE_RW | X86_PTE_P);
-                pThis->fRemappedVGA = true;
+                vgaMarkRemapped(pThis, GCPhys - 0xa0000);
             }
 #endif /* !IN_RC */
@@ -4655 +4693 @@
         pHlp->pfnPrintf(pHlp, " Linear display start : 0x%04x\n", pThis->vbe_start_addr);
         pHlp->pfnPrintf(pHlp, " Selected bank: 0x%04x\n", pThis->vbe_regs[VBE_DISPI_INDEX_BANK]);
+        pHlp->pfnPrintf(pHlp, " DAC: %d-bit\n", pThis->vbe_regs[VBE_DISPI_INDEX_ENABLE] & VBE_DISPI_8BIT_DAC ? 8 : 6);
     }
 }
@@ -4808 +4847 @@
     {
         PDMDevHlpMmioResetRegion(pDevIns, pThis->hMmioLegacy);
-        pThis->fRemappedVGA = false;
+        vgaResetRemapped(pThis);
     }
 
@@ -4836 +4875 @@
     {
         PDMDevHlpMmioResetRegion(pDevIns, pThis->hMmioLegacy);
-        pThis->fRemappedVGA = false;
+        vgaResetRemapped(pThis);
     }
 
@@ -6057 +6096 @@
     {
         PDMDevHlpMmioResetRegion(pDevIns, pThis->hMmioLegacy);
-        pThis->fRemappedVGA = false;
+        vgaResetRemapped(pThis);
     }
 

trunk/src/VBox/Devices/Graphics/DevVGA.h

@@ -352 +352 @@
     /** Bitmap tracking dirty pages. */
     uint64_t                    bmDirtyBitmap[VGA_VRAM_MAX / GUEST_PAGE_SIZE / 64];
+    /** Bitmap tracking remapped pages (only needs 16 bits). */
+    uint64_t                    bmPageMapBitmap;
 
     /** Flag indicating that there are dirty bits. This is used to optimize the handler resetting. */
@@ -526 +528 @@
 AssertCompileMemberAlignment(VGASTATE, last_ch_attr, 8);
 AssertCompileMemberAlignment(VGASTATE, u32Marker, 8);
+AssertCompile(sizeof(uint64_t)/*bmPageMapBitmap*/ >= (_64K / GUEST_PAGE_SIZE / 8));
 #endif