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diff --git a/private/nw/rdr/synch.txt b/private/nw/rdr/synch.txt
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+This file describes use of resources and spin locks with the netware
+redirector.  There are 2 major sections - global locks, and per structure
+locks.  Each subsection names a lock or resources and list all of the
+global variable, and structure fields it protects.
+
+
+1.  Global Locks
+
+1.1  ScbSpinLock
+        - ScbQueue
+        - NpScb fields -> ScbLinks
+        - Nearest server table.
+
+1.2  Rcb->Resource
+        - ServerNameTable
+        - FileNameTable, Fcb->PrefixEntry
+        - Rcb fields -> OpenCount
+        - Synchronize access to newly created FCBs
+        - DefaultUserName, DefaultPassword, DefaultServerName.
+        - Fcb->IcbList, Icb->ListEntry
+        - DriveMapTable
+        - Vcb->ReferenceCount, Vcb->FcbList, Vcb->FcbCount, GlobalVcbListEntry
+        - Scb->ScbSpecificVcbQueue, Scb->VcbCount, OpenFileCount, AttachCount
+        - GlobalVcbList, CurrentVcbEntry
+
+1.3  NwScavengerSpinLock
+        - NwScavengerTickCount
+
+1.4  Front of the SCB queue
+        - Icb->State, HasRemoteHandle
+        - NpScb->State
+        - pScb->UserName, pScb->Password
+        - Fcb->FileSize (except during create)
+
+1.5  NwMessageSpinLock
+        - NwGetMessageList
+
+1.6  NwPendingLockSpinLock
+        - NwPendingLockList
+
+1.7  NwFcbTableResource
+        - FCB / ICB creation.
+
+2.  Per structure locks
+
+2.1   SCB->NpScbSpinLock
+          - NpScb fields -> Sending, Receiving, OkToReceive, TimeOut,
+                            MaxTimeOut, Requests, RetryCount, Reference
+
+2.2  FCB->Resource
+          - Fcb->  Attributes, LastModifiedDate, LastModifiedTime
+                   State, FileLockList, PendingLockList,
+
+2.3  Front of the SCB queue
+          - Icb->FileLockList
+
+2.4  LOGON->CredListResource
+     Protects the credentials on the cred list
+     and the list pointers.  Acquire shared for
+     read access to the list.  Acquire exclusive
+     for write access to the list.
+
+In order to eliminate dead locks, locks should be acquired in the following
+order (if multiple locks are needed).
+
+RCB->Resource
+FCB->Resource
+NwScavengerSpinLock
+LOGON->CredListResource
+ScbSpinLock
+SCB->NpScbSpinLock
+
+A thread cannot wait for the SCB queue while holding any other lock.
+