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