[viostor]: Introduce action-on-reset feature from vioscsi

The action-on-reset determines what the driver should do when a bus reset request arrives. It can be configured to:
- complete pending requests,
- do nothing,
- bug check.

This feature is already present in vioscsi but not in viostor.

Signed-Off-By: Martin Drab <martin.drab@virtuozzo.com>

Author: Martin Drab

viostor/virtio_stor.c

@@ -486,6 +486,9 @@ VirtIoFindAdapter(IN PVOID DeviceExtension,
     adaptExt->slot_number = ConfigInfo->SlotNumber;
     adaptExt->dump_mode = IsCrashDumpMode;
 
+    adaptExt->action_on_reset = VirtioResetCompleteRequests;
+    VioStorReadRegistryParameter(DeviceExtension, REGISTRY_ACTION_ON_RESET, FIELD_OFFSET(ADAPTER_EXTENSION, action_on_reset));
+
     ConfigInfo->Master = TRUE;
     ConfigInfo->ScatterGather = TRUE;
     ConfigInfo->DmaWidth = Width32Bits;
@@ -1193,7 +1196,21 @@ VirtIoStartIo(IN PVOID DeviceExtension, IN PSCSI_REQUEST_BLOCK Srb)
         case SRB_FUNCTION_RESET_DEVICE:
         case SRB_FUNCTION_RESET_LOGICAL_UNIT:
             {
-                CompletePendingRequests(DeviceExtension);
+                switch (adaptExt->action_on_reset)
+                {
+                    case VirtioResetCompleteRequests:
+                        RhelDbgPrint(TRACE_LEVEL_INFORMATION, " Completing all pending SRBs\n");
+                        CompletePendingRequests(DeviceExtension);
+                        break;
+                    case VirtioResetDoNothing:
+                        RhelDbgPrint(TRACE_LEVEL_INFORMATION, " Doing nothing with all pending SRBs\n");
+                        break;
+                    case VirtioResetBugCheck:
+                        RhelDbgPrint(TRACE_LEVEL_INFORMATION, " Let's bugcheck due to this reset event\n");
+                        KeBugCheckEx(0xDEADDEAD, (ULONG_PTR)Srb, SRB_PATH_ID(Srb), SRB_TARGET_ID(Srb), SRB_LUN(Srb));
+                        break;
+                }
+            
                 CompleteRequestWithStatus(DeviceExtension, (PSRB_TYPE)Srb, SRB_STATUS_SUCCESS);
 #ifdef DBG
                 RhelDbgPrint(TRACE_LEVEL_INFORMATION,
@@ -1415,7 +1432,21 @@ VirtIoResetBus(IN PVOID DeviceExtension, IN ULONG PathId)
     PADAPTER_EXTENSION adaptExt;
     adaptExt = (PADAPTER_EXTENSION)DeviceExtension;
 
-    CompletePendingRequests(DeviceExtension);
+    switch (adaptExt->action_on_reset)
+    {
+        case VirtioResetCompleteRequests:
+            RhelDbgPrint(TRACE_LEVEL_INFORMATION, " Completing all pending SRBs\n");
+            CompletePendingRequests(DeviceExtension);
+            break;
+        case VirtioResetDoNothing:
+            RhelDbgPrint(TRACE_LEVEL_INFORMATION, " Doing nothing with all pending SRBs\n");
+            break;
+        case VirtioResetBugCheck:
+            RhelDbgPrint(TRACE_LEVEL_INFORMATION, " Let's bugcheck due to this reset event\n");
+            KeBugCheckEx(0xDEADDEAD, (ULONG_PTR)DeviceExtension, PathId, (ULONG_PTR)-1, (ULONG_PTR)-1);
+            break;
+    }
+
     return TRUE;
 }
 

viostor/virtio_stor.h

@@ -206,10 +206,18 @@ typedef struct _REQUEST_LIST
     ULONG srb_cnt;
 } REQUEST_LIST, *PREQUEST_LIST;
 
+#define REGISTRY_ACTION_ON_RESET        "VirtioActionOnReset"
+
+typedef enum ACTION_ON_RESET
+{
+    VirtioResetCompleteRequests,
+    VirtioResetDoNothing,
+    VirtioResetBugCheck = 0xDEADDEAD,
+} ACTION_ON_RESET;
+
 typedef struct _ADAPTER_EXTENSION
 {
     VirtIODevice vdev;
-
     PVOID pageAllocationVa;
     ULONG pageAllocationSize;
     ULONG pageOffset;
@@ -256,6 +264,7 @@ typedef struct _ADAPTER_EXTENSION
     REQUEST_LIST processing_srbs[MAX_CPU];
     BOOLEAN reset_in_progress;
     ULONGLONG fw_ver;
+    ACTION_ON_RESET       action_on_reset;
 #ifdef DBG
     LONG srb_cnt;
     LONG inqueue_cnt;