IoReleaseVpbSpinLock function (ntifs.h)

  • Article

The IoReleaseVpbSpinLock routine releases the Volume Parameter Block (VPB) spin lock.

Syntax

void IoReleaseVpbSpinLock(
  [in] KIRQL Irql
);

Parameters

[in] Irql

Saved IRQL value returned by IoAcquireVpbSpinLock when the VPB spin lock was acquired.

Return value

None

Remarks

This routine is the reciprocal to IoAcquireVpbSpinLock. Every successful call to IoAcquireVpbSpinLock must be matched by a subsequent call to IoReleaseVpbSpinLock.

Before using IoAcquireVpbSpinLock and IoReleaseVpbSpinLock, driver writers are strongly encouraged to study the way these routines are used in the FASTFAT sample.

The holder of the VPB spin lock executes at IRQL DISPATCH_LEVEL after calling IoAcquireVpbSpinLock. IoReleaseVpbSpinLock restores the caller's original IRQL.

Requirements

Requirement Value
Target Platform Universal
Header ntifs.h (include Ntifs.h)
Library NtosKrnl.lib
DLL NtosKrnl.exe
IRQL DISPATCH_LEVEL
DDI compliance rules HwStorPortProhibitedDDIs(storport)

See also

IoAcquireVpbSpinLock