Changeset 39414 in vbox

Timestamp:

Nov 24, 2011 9:52:15 PM (13 years ago)

Author:

vboxsync

svn:sync-xref-src-repo-rev:

75036

Message:

PDMBlkCache: Clear all entries on reset to prevent that unwritten data is in the cache which can lead to data corruption in case the cache isn't used after the reset

Location:

trunk

Files:

• include/VBox/vmm/pdmblkcache.h (modified) (1 diff)
• src/VBox/Devices/Storage/DrvVD.cpp (modified) (1 diff)
• src/VBox/VMM/VMMR3/PDMBlkCache.cpp (modified) (1 diff)

trunk/include/VBox/vmm/pdmblkcache.h

@@ -406 +406 @@
 VMMR3DECL(int) PDMR3BlkCacheResume(PPDMBLKCACHE pBlkCache);
 
+/**
+ * Clears the block cache and removes all entries. The cache waits until all
+ * I/O transfers completed.
+ *
+ * @returns VBox status code.
+ * @param   pBlkCache       The cache instance.
+ */
+VMMR3DECL(int) PDMR3BlkCacheClear(PPDMBLKCACHE pBlkCache);
+
 /** @} */
 

trunk/src/VBox/Devices/Storage/DrvVD.cpp

@@ -1999 +1999 @@
     LogFlowFunc(("\n"));
     PVBOXDISK pThis = PDMINS_2_DATA(pDrvIns, PVBOXDISK);
+
+    if (pThis->pBlkCache)
+    {
+        int rc = PDMR3BlkCacheClear(pThis->pBlkCache);
+        AssertRC(rc);
+    }
 
     if (pThis->fBootAccelEnabled)

trunk/src/VBox/VMM/VMMR3/PDMBlkCache.cpp

@@ -2740 +2740 @@
 }
 
+VMMR3DECL(int) PDMR3BlkCacheClear(PPDMBLKCACHE pBlkCache)
+{
+    int rc = VINF_SUCCESS;
+    PPDMBLKCACHEGLOBAL pCache = pBlkCache->pCache;
+
+    /*
+     * Commit all dirty entries now (they are waited on for completion during the
+     * destruction of the AVL tree below).
+     * The exception is if the VM was paused because of an I/O error before.
+     */
+    if (!ASMAtomicReadBool(&pCache->fIoErrorVmSuspended))
+        pdmBlkCacheCommit(pBlkCache);
+
+    /* Make sure nobody is accessing the cache while we delete the tree. */
+    pdmBlkCacheLockEnter(pCache);
+    RTSemRWRequestWrite(pBlkCache->SemRWEntries, RT_INDEFINITE_WAIT);
+    RTAvlrU64Destroy(pBlkCache->pTree, pdmBlkCacheEntryDestroy, pCache);
+    RTSemRWReleaseWrite(pBlkCache->SemRWEntries);
+
+    pdmBlkCacheLockLeave(pCache);
+    return rc;
+}
+