Fixed bug in partition driver:

When Block I/O detects the media changed, block driver will reinstall block I/O protocol. If it happened during start() of partition driver, the reinstall protocol would results in the reentrant of the start(). In the patch, we check status of child detection to see whether need clean up the opened block I/O protocol in Start().

Besides, some checking of return status added in usbbus driver to improve robusticiy of the driver.

git-svn-id: https://edk2.svn.sourceforge.net/svnroot/edk2/trunk/edk2@2288 6f19259b-4bc3-4df7-8a09-765794883524

EdkModulePkg/Universal/Disk/Partition/Dxe/Gpt.c

@@ -75,7 +75,7 @@ PartitionSetCrc (
   IN OUT EFI_TABLE_HEADER *Hdr
   );
 
-BOOLEAN
+EFI_STATUS
 PartitionInstallGptChildHandles (
   IN  EFI_DRIVER_BINDING_PROTOCOL  *This,
   IN  EFI_HANDLE                   Handle,
@@ -96,8 +96,9 @@ Arguments:
   DevicePath - Parent Device Path
 
 Returns:
-  TRUE       - Valid GPT disk
-  FALSE      - Not a valid GPT disk
+  EFI_SUCCESS  - Valid GPT disk
+  EFI_MEDIA_CHANGED - Media changed Detected
+  !EFI_SUCCESS - Not a valid GPT disk
 
 --*/
 {
@@ -110,7 +111,7 @@ Returns:
   EFI_PARTITION_ENTRY         *PartEntry;
   EFI_PARTITION_ENTRY_STATUS  *PEntryStatus;
   UINTN                       Index;
-  BOOLEAN                     GptValid;
+  EFI_STATUS                  GptValid;
   HARDDRIVE_DEVICE_PATH       HdDev;
 
   ProtectiveMbr = NULL;
@@ -125,14 +126,14 @@ Returns:
   DEBUG ((EFI_D_INFO, " BlockSize : %d \n", BlockSize));
   DEBUG ((EFI_D_INFO, " LastBlock : %x \n", LastBlock));
 
-  GptValid = FALSE;
+  GptValid = EFI_NOT_FOUND;
 
   //
   // Allocate a buffer for the Protective MBR
   //
   ProtectiveMbr = AllocatePool (BlockSize);
   if (ProtectiveMbr == NULL) {
-    return FALSE;
+    return EFI_NOT_FOUND;
   }
 
   //
@@ -146,6 +147,7 @@ Returns:
                       ProtectiveMbr
                       );
   if (EFI_ERROR (Status)) {
+    GptValid = Status;
     goto Done;
   }
   //
@@ -224,6 +226,7 @@ Returns:
                     PartEntry
                     );
   if (EFI_ERROR (Status)) {
+    GptValid = Status;
     DEBUG ((EFI_D_INFO, " Partition Entry ReadBlocks error\n"));
     goto Done;
   }
@@ -246,7 +249,7 @@ Returns:
   //
   // If we got this far the GPT layout of the disk is valid and we should return true
   //
-  GptValid = TRUE;
+  GptValid = EFI_SUCCESS;
 
   //
   // Create child device handles