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IOBDBlockStorageDriver

Inherits from:
Declared In:

Overview

Generic BD Driver.

Discussion

Storage drivers are split into two parts: the Generic Driver handles all generic device issues, independent of the lower-level transport mechanism (e.g. SCSI, ATA, USB, FireWire). All storage operations at the Generic Driver level are translated into a series of generic device operations. These operations are passed via the Device Nub to a Transport Driver, which implements the appropriate transport-dependent protocol to execute these operations.

To determine the write-protect state of a device (or media), for example, the generic driver would issue a call to the Transport Driver's reportWriteProtection method. If this were a SCSI device, its Transport Driver would issue a Mode Sense command to extract the write-protection status bit. The Transport Driver then reports true or false to the generic driver.

The generic driver therefore has no knowledge of, or involvement with, the actual commands and mechanisms used to communicate with the device. It is expected that the generic driver will rarely, if ever, need to be subclassed to handle device idiosyncrasies; rather, the Transport Driver should be changed via overrides.

A generic driver could be subclassed to create a different type of generic device. The generic driver IOBDBlockStorageDriver class is a subclass of IODVDBlockStorageDriver, adding BD functions. Similarly, the Transport Driver IOBDBlockStorageDevice is a subclass of IODVDBlockStorageDevice, adding BD functions.


Functions

splitTrack

splitTrack

public

virtual IOReturn splitTrack(
    UInt32 address);
Parameters
address

As documented by MMC.

Return Value

Returns the status of the operation.

Discussion

Issue an MMC RESERVE TRACK command with the ARSV bit.


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Last Updated: 2008-12-19