A SCSI-device-specific driver linked with the system-supplied SCSI tape class driver. If a tape miniclass driver calls only routines in the tape class driver, the miniclass driver can be portable across Microsoft operating systems that support Win32 applications.
Translation buffer
See TLB.
Thread environment block
A user-mode thread object represents a path of execution within the current process. Every user-mode thread object is implemented through the use of an embedded kernel-mode thread object.
A kernel-mode thread object is an instance of a Kernel-defined dispatcher object type. The thread that it represents is the basic schedulable entity in NT.
A thread object:
· Is dispatched for execution by the Kernel
· Has the following properties at any given moment:
Dispatch state
Priority
Context
Execution mode (kernel or user)
Affinity
· Is “owned by” a process object but can attach itself to another process’s address space
Usually, most NT drivers execute in the context of the currently running thread, that is, in an arbitrary thread context. While a file system driver can create an independent process for its own device-dedicated threads, NT file systems usually avoid setting up a driver-created process and threads in order to conserve system memory and to avoid the overhead of context switches.
FSs (and other NT drivers) can set up device-dedicated (system-process) threads and/or FSs can use system worker threads if they need a driver-specific thread context in which to execute. NT drivers use kernel-mode Ps (Process Structure) routines to create processes and/or device-dedicated threads. FSs call routines supplied by the NT Executive Support component to use system worker threads.
Target identifier
One of up to eight target controllers on a SCSI-II bus through which peripheral devices are addressable, either as numbered TIDs or as logical units (LUs) subordinate to a particular TID.
A timer object is an instance of a Kernel-defined dispatcher object type. User-mode timer objects can be used to synchronize the execution of specific actions, optionally an APC, with time. Kernel-mode timer objects are used to synchronize the execution of specific actions, in particular a DPC, with time.
When set to a specified expiration time:
· The timer’s state is reset to Not-Signaled.
· The timer is placed in a queue that is ordered according to expiration time.
When its expiration time arrives a timer is set to the Signaled state. When a notification timer is Signaled, all waiting threads have their wait satisfied and the state of the timer remains Signaled until it is explicitly reset. When a synchronization timer expires, its state is set to Signaled until a single waiting thread is released and then the timer is reset to the Not-Signaled state.
A timer can expire just once, or can be set to expire repeatedly at a given interval (a periodic timer).
The I/O Manager also supplies timer functions for drivers to use.
Translation lookaside buffer
(Not directly accessible by system software for the i386; otherwise, an on-chip virtual-to-physical-page address translation cache for high-end x86 and MIPS microprocessors.)
slang: A SCSI peripheral device of an unknown class.
A security object type, representing an authenticated user process. Every process has an assigned token, which becomes the default token for each of that process’s threads. However, an individual thread can be assigned a token that overrides this default.
A body of code in the Kernel to which the processor transfers control when an interrupt or exception occurs. The trap handler determines the type of condition that caused the interrupt or exception and transfers control to an ISR or exception handler.