MdeModulePkg/DxeCore: Fixed Interface returned by CoreOpenProtocol

Change since v4: Revise the patch based on V4 sent by Amit Kumar
1) Only return the corresponding protocol interface in *Interface
if the return status is EFI_SUCCESS or EFI_ALREADY_STARTED.
2) Interface is returned unmodified for all error conditions except
EFI_UNSUPPORTED and EFI_ALREADY_STARTED, NULL will be returned in
*Interface when EFI_UNSUPPORTED and Attributes is not
EFI_OPEN_PROTOCOL_TEST_PROTOCOL, the protocol interface will be
returned in *Interface when EFI_ALREADY_STARTED.

Change since v3:
1) Fixed issue when Attributes = EFI_OPEN_PROTOCOL_TEST_PROTOCOL
and Inteface = NULL case. [Reported by:star.zeng at intel.com]

Change Since v2:
1) Modified to use EFI_ERROR to get status code

Change since v1:
1) Fixed typo protocal to protocol
2) Fixed coding style

Cc: Laszlo Ersek <lersek@redhat.com>
Cc: Amit Kumar <amit.ak@samsung.com>
Cc: Michael D Kinney <michael.d.kinney@intel.com>
Cc: Liming Gao <liming.gao@intel.com>
Cc: Gabriel Somlo <gsomlo@gmail.com>
Contributed-under: TianoCore Contribution Agreement 1.0
Signed-off-by: Amit Kumar <amit.ak@samsung.com>
Signed-off-by: Star Zeng <star.zeng@intel.com>
Reviewed-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Laszlo Ersek <lersek@redhat.com>
Tested-by: Gabriel Somlo <gsomlo@gmail.com>

diff --git a/MdeModulePkg/Core/Dxe/Hand/Handle.c b/MdeModulePkg/Core/Dxe/Hand/Handle.c
index 9b2809dbe5c3d054403a2c2bcc5bb26b71b55c13..3ed187b27949d3b5d79b28ad52050f73554e1e06 100644 (file)
--- a/MdeModulePkg/Core/Dxe/Hand/Handle.c
+++ b/MdeModulePkg/Core/Dxe/Hand/Handle.c
@@ -1004,12 +1004,8 @@ CoreOpenProtocol (
   //\r
   // Check for invalid Interface\r
   //\r
   //\r
   // Check for invalid Interface\r
   //\r

-  if (Attributes != EFI_OPEN_PROTOCOL_TEST_PROTOCOL) {\r
-    if (Interface == NULL) {\r
-      return EFI_INVALID_PARAMETER;\r
-    } else {\r
-      *Interface = NULL;\r
-    }\r
+  if ((Attributes != EFI_OPEN_PROTOCOL_TEST_PROTOCOL) && (Interface == NULL)) {\r
+    return EFI_INVALID_PARAMETER;\r

   }\r
 \r
   //\r
   }\r
 \r
   //\r


@@ -1076,12 +1072,6 @@ CoreOpenProtocol (
     goto Done;\r
   }\r
 \r
     goto Done;\r
   }\r
 \r

-  //\r
-  // This is the protocol interface entry for this protocol\r
-  //\r
-  if (Attributes != EFI_OPEN_PROTOCOL_TEST_PROTOCOL) {\r
-    *Interface = Prot->Interface;\r
-  }\r

   Status = EFI_SUCCESS;\r
 \r
   ByDriver        = FALSE;\r
   Status = EFI_SUCCESS;\r
 \r
   ByDriver        = FALSE;\r


@@ -1177,8 +1167,28 @@ CoreOpenProtocol (
   }\r
 \r
 Done:\r
   }\r
 \r
 Done:\r

+\r
+  if (Attributes != EFI_OPEN_PROTOCOL_TEST_PROTOCOL) {\r
+    //\r
+    // Keep Interface unmodified in case of any Error\r
+    // except EFI_ALREADY_STARTED and EFI_UNSUPPORTED.\r
+    //\r
+    if (!EFI_ERROR (Status) || Status == EFI_ALREADY_STARTED) {\r
+      //\r
+      // EFI_ALREADY_STARTED is not an error for bus driver.\r
+      // Return the corresponding protocol interface.\r
+      //\r
+      *Interface = Prot->Interface;\r
+    } else if (Status == EFI_UNSUPPORTED) {\r
+      //\r
+      // Return NULL Interface if Unsupported Protocol.\r
+      //\r
+      *Interface = NULL;\r
+    }\r
+  }\r
+\r

   //\r
   //\r

-  // Done. Release the database lock are return\r
+  // Done. Release the database lock and return\r

   //\r
   CoreReleaseProtocolLock ();\r
   return Status;\r
   //\r
   CoreReleaseProtocolLock ();\r
   return Status;\r