From b9f5240173b1210e3a97cc35570c3cdfeef4741e Mon Sep 17 00:00:00 2001
From: Pierre Schweitzer <pierre@reactos.org>
Date: Mon, 29 Dec 2014 23:14:42 +0000
Subject: [PATCH] [RAMDISK] Implement RamdiskQueryDeviceRelations() when the
 device is a drive
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According to Hervé, this allows booting ReactOS livecd using PXE (with one of his patch).

svn path=/trunk/; revision=65902
---
 .../drivers/storage/class/ramdisk/ramdisk.c   | 39 ++++++++++++++++++-
 1 file changed, 37 insertions(+), 2 deletions(-)

diff --git a/reactos/drivers/storage/class/ramdisk/ramdisk.c b/reactos/drivers/storage/class/ramdisk/ramdisk.c
index 143a6f6f600..2cbfdaa7d8b 100644
--- a/reactos/drivers/storage/class/ramdisk/ramdisk.c
+++ b/reactos/drivers/storage/class/ramdisk/ramdisk.c
@@ -1731,10 +1731,45 @@ RamdiskQueryDeviceRelations(IN DEVICE_RELATION_TYPE Type,
     DeviceExtension = DeviceObject->DeviceExtension;
     if (DeviceExtension->Type == RamdiskDrive)
     {
+        NTSTATUS Status;
+        PDEVICE_RELATIONS DeviceRelations;
+
+        //
+        // We're a child device, only handle target device relations
+        //
+        if (Type != TargetDeviceRelation)
+        {
+            Status = Irp->IoStatus.Status;
+            IoCompleteRequest(Irp, IO_NO_INCREMENT);
+            return Status;
+        }
+
         //
-        // FIXME: TODO
+        // Allocate a buffer big enough to contain only one DO
         //
-        UNIMPLEMENTED_DBGBREAK();
+        DeviceRelations = ExAllocatePoolWithTag(PagedPool, sizeof(DeviceRelations), 'dmaR');
+        if (DeviceRelations != NULL)
+        {
+            //
+            // Reference the DO and add it to the buffer
+            //
+            ObReferenceObject(DeviceObject);
+            DeviceRelations->Objects[0] = DeviceObject;
+            DeviceRelations->Count = 1;
+            Status = STATUS_SUCCESS;
+        }
+        else
+        {
+            Status = STATUS_INSUFFICIENT_RESOURCES;
+        }
+
+        //
+        // Return our processing & complete
+        //
+        Irp->IoStatus.Information = (ULONG_PTR)DeviceRelations;
+        Irp->IoStatus.Status = Status;
+        IoCompleteRequest(Irp, IO_NO_INCREMENT);
+        return Status;
     }
     
     //
-- 
2.17.1