Changeset 38521 in vbox

Timestamp:

Aug 25, 2011 8:23:13 AM (13 years ago)

Author:

vboxsync

Message:

VHD: Fix the async I/O version too

File:

• trunk/src/VBox/Storage/VHD.cpp (modified) (1 diff)

trunk/src/VBox/Storage/VHD.cpp

@@ -2284 +2284 @@
 
         /*
+         * Clip read range to remain in this data block.
+         */
+        cbRead = RT_MIN(cbRead, (pImage->cbDataBlock - (cBATEntryIndex * VHD_SECTOR_SIZE)));
+
+        /*
          * If the block is not allocated the content of the entry is ~0
          */
         if (pImage->pBlockAllocationTable[cBlockAllocationTableEntry] == ~0U)
-        {
-            /* Return block size as read. */
-            *pcbActuallyRead = RT_MIN(cbRead, pImage->cSectorsPerDataBlock * VHD_SECTOR_SIZE);
-            return VERR_VD_BLOCK_FREE;
-        }
-
-        uVhdOffset = ((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry] + pImage->cDataBlockBitmapSectors + cBATEntryIndex) * VHD_SECTOR_SIZE;
-        LogFlowFunc(("uVhdOffset=%llu cbRead=%u\n", uVhdOffset, cbRead));
-
-        /*
-         * Clip read range to remain in this data block.
-         */
-        cbRead = RT_MIN(cbRead, (pImage->cbDataBlock - (cBATEntryIndex * VHD_SECTOR_SIZE)));
-
-        /* Read in the block's bitmap. */
-        PVDMETAXFER pMetaXfer;
-        rc = vdIfIoIntFileReadMetaAsync(pImage->pIfIo, pImage->pStorage,
-                                        ((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry]) * VHD_SECTOR_SIZE,
-                                        pImage->pu8Bitmap, pImage->cbDataBlockBitmap,
-                                        pIoCtx, &pMetaXfer, NULL, NULL);
-
-        if (RT_SUCCESS(rc))
-        {
-            uint32_t cSectors = 0;
-
-            vdIfIoIntMetaXferRelease(pImage->pIfIo, pMetaXfer);
-            if (vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
+            rc = VERR_VD_BLOCK_FREE;
+        else
+        {
+            uVhdOffset = ((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry] + pImage->cDataBlockBitmapSectors + cBATEntryIndex) * VHD_SECTOR_SIZE;
+            LogFlowFunc(("uVhdOffset=%llu cbRead=%u\n", uVhdOffset, cbRead));
+
+            /* Read in the block's bitmap. */
+            PVDMETAXFER pMetaXfer;
+            rc = vdIfIoIntFileReadMetaAsync(pImage->pIfIo, pImage->pStorage,
+                                            ((uint64_t)pImage->pBlockAllocationTable[cBlockAllocationTableEntry]) * VHD_SECTOR_SIZE,
+                                            pImage->pu8Bitmap, pImage->cbDataBlockBitmap,
+                                            pIoCtx, &pMetaXfer, NULL, NULL);
+
+            if (RT_SUCCESS(rc))
             {
-                cBATEntryIndex++;
-                cSectors = 1;
-
-                /*
-                 * The first sector being read is marked dirty, read as much as we
-                 * can from child. Note that only sectors that are marked dirty
-                 * must be read from child.
-                 */
-                while (   (cSectors < (cbRead / VHD_SECTOR_SIZE))
-                       && vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
+                uint32_t cSectors = 0;
+
+                vdIfIoIntMetaXferRelease(pImage->pIfIo, pMetaXfer);
+                if (vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
                 {
                     cBATEntryIndex++;
-                    cSectors++;
+                    cSectors = 1;
+
+                    /*
+                     * The first sector being read is marked dirty, read as much as we
+                     * can from child. Note that only sectors that are marked dirty
+                     * must be read from child.
+                     */
+                    while (   (cSectors < (cbRead / VHD_SECTOR_SIZE))
+                           && vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
+                    {
+                        cBATEntryIndex++;
+                        cSectors++;
+                    }
+
+                    cbRead = cSectors * VHD_SECTOR_SIZE;
+
+                    LogFlowFunc(("uVhdOffset=%llu cbRead=%u\n", uVhdOffset, cbRead));
+                    rc = vdIfIoIntFileReadUserAsync(pImage->pIfIo, pImage->pStorage,
+                                                    uVhdOffset, pIoCtx, cbRead);
                 }
-
-                cbRead = cSectors * VHD_SECTOR_SIZE;
-
-                LogFlowFunc(("uVhdOffset=%llu cbRead=%u\n", uVhdOffset, cbRead));
-                rc = vdIfIoIntFileReadUserAsync(pImage->pIfIo, pImage->pStorage,
-                                                uVhdOffset, pIoCtx, cbRead);
+                else
+                {
+                    /*
+                     * The first sector being read is marked clean, so we should read from
+                     * our parent instead, but only as much as there are the following
+                     * clean sectors, because the block may still contain dirty sectors
+                     * further on. We just need to compute the number of clean sectors
+                     * and pass it to our caller along with the notification that they
+                     * should be read from the parent.
+                     */
+                    cBATEntryIndex++;
+                    cSectors = 1;
+
+                    while (   (cSectors < (cbRead / VHD_SECTOR_SIZE))
+                           && !vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
+                    {
+                        cBATEntryIndex++;
+                        cSectors++;
+                    }
+
+                    cbRead = cSectors * VHD_SECTOR_SIZE;
+                    LogFunc(("Sectors free: uVhdOffset=%llu cbRead=%u\n", uVhdOffset, cbRead));
+                    rc = VERR_VD_BLOCK_FREE;
+                }
             }
             else
-            {
-                /*
-                 * The first sector being read is marked clean, so we should read from
-                 * our parent instead, but only as much as there are the following
-                 * clean sectors, because the block may still contain dirty sectors
-                 * further on. We just need to compute the number of clean sectors
-                 * and pass it to our caller along with the notification that they
-                 * should be read from the parent.
-                 */
-                cBATEntryIndex++;
-                cSectors = 1;
-
-                while (   (cSectors < (cbRead / VHD_SECTOR_SIZE))
-                       && !vhdBlockBitmapSectorContainsData(pImage, cBATEntryIndex))
-                {
-                    cBATEntryIndex++;
-                    cSectors++;
-                }
-
-                cbRead = cSectors * VHD_SECTOR_SIZE;
-                LogFunc(("Sectors free: uVhdOffset=%llu cbRead=%u\n", uVhdOffset, cbRead));
-                rc = VERR_VD_BLOCK_FREE;
-            }
-        }
-        else
-            AssertMsg(rc == VERR_VD_NOT_ENOUGH_METADATA, ("Reading block bitmap failed rc=%Rrc\n", rc));
+                AssertMsg(rc == VERR_VD_NOT_ENOUGH_METADATA, ("Reading block bitmap failed rc=%Rrc\n", rc));
+        }
     }
     else