[ros-diffs] [arty] 34899: Fix (among other things) failure to boot when a CD is not inserted, caused by the new (correct) ASSERT in mutex acquisition in MmProbeAndLockPages, which was erroneously being called from IoBuildAsynchronousFsdRequest at DISPATCH_LEVEL. The only correct course of action when calling IoBuildAsynchronousFsdRequest at DISPATCH_LEVEL is to MmBuildMdlForNonPagedPool since the buffer must be nonpaged (if the IRP completes synchronously, we'll still be at DISPATCH_LEVEL) This is the case

Author: arty
Date: Mon Jul 28 07:38:47 2008
New Revision: 34899

URL: http://svn.reactos.org/svn/reactos?rev=34899&view=rev
Log:
Fix (among other things) failure to boot when a CD is not inserted, caused by
the new (correct) ASSERT in mutex acquisition in MmProbeAndLockPages, which
was erroneously being called from IoBuildAsynchronousFsdRequest at
DISPATCH_LEVEL.

The only correct course of action when calling IoBuildAsynchronousFsdRequest
at DISPATCH_LEVEL is to MmBuildMdlForNonPagedPool since the buffer must be 
nonpaged (if the IRP completes synchronously, we'll still be at DISPATCH_LEVEL)
This is the case when direct io is done at DISPATCH_LEVEL using
IoBuildAsynchronousFsdRequest.

Modified:
    trunk/reactos/drivers/storage/scsiport/scsiport.c
    trunk/reactos/ntoskrnl/io/iomgr/irp.c

Modified: trunk/reactos/drivers/storage/scsiport/scsiport.c
URL: http://svn.reactos.org/svn/reactos/trunk/reactos/drivers/storage/scsiport/sc...
==============================================================================
--- trunk/reactos/drivers/storage/scsiport/scsiport.c [iso-8859-1] (original)
+++ trunk/reactos/drivers/storage/scsiport/scsiport.c [iso-8859-1] Mon Jul 28 07:38:47 2008
@@ -4405,7 +4405,8 @@

if (Irp->MdlAddress != NULL)
     {
-        MmUnlockPages(Irp->MdlAddress);
+		/* We don't need to unlock this MDL because the request could 
+		 * only have come from dispatch level */
         IoFreeMdl(Irp->MdlAddress);
         Irp->MdlAddress = NULL;
     }

Modified: trunk/reactos/ntoskrnl/io/iomgr/irp.c
URL: http://svn.reactos.org/svn/reactos/trunk/reactos/ntoskrnl/io/iomgr/irp.c?rev...
==============================================================================
--- trunk/reactos/ntoskrnl/io/iomgr/irp.c [iso-8859-1] (original)
+++ trunk/reactos/ntoskrnl/io/iomgr/irp.c [iso-8859-1] Mon Jul 28 07:38:47 2008
@@ -682,23 +682,30 @@
                 return NULL;
             }

-            /* Probe and Lock */
-            _SEH_TRY
-            {
-                /* Do the probe */
-                MmProbeAndLockPages(Irp->MdlAddress,
-                                    KernelMode,
-                                    MajorFunction == IRP_MJ_READ ?
-                                    IoWriteAccess : IoReadAccess);
-            }
-            _SEH_HANDLE
-            {
-                /* Free the IRP and its MDL */
-                IoFreeMdl(Irp->MdlAddress);
-                IoFreeIrp(Irp);
-                Irp = NULL;
-            }
-            _SEH_END;
+			if (KeGetCurrentIrql() >= DISPATCH_LEVEL)
+			{
+				MmBuildMdlForNonPagedPool(Irp->MdlAddress);
+			}
+			else
+			{
+				/* Probe and Lock */
+				_SEH_TRY
+				{
+					/* Do the probe */
+					MmProbeAndLockPages(Irp->MdlAddress,
+										KernelMode,
+										MajorFunction == IRP_MJ_READ ?
+										IoWriteAccess : IoReadAccess);
+				}
+				_SEH_HANDLE
+				{
+					/* Free the IRP and its MDL */
+					IoFreeMdl(Irp->MdlAddress);
+					IoFreeIrp(Irp);
+					Irp = NULL;
+				}
+				_SEH_END;
+			}

/* This is how we know if we failed during the probe */
             if (!Irp) return NULL;
@@ -1344,7 +1351,7 @@
     Mdl = Irp->MdlAddress;
     while (Mdl)
     {
-        MmUnlockPages(Mdl);
+		MmUnlockPages(Mdl);
         Mdl = Mdl->Next;
     }