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KsMoveIrpsOnCancelableQueue function (ks.h)

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The KsMoveIrpsOnCancelableQueue function moves the specified IRPs from the SourceList parameter to the DestinationList parameter depending on the value returned from the minidriver-defined KStrIrpListCallback function.

Syntax

KSDDKAPI NTSTATUS KsMoveIrpsOnCancelableQueue(
  [in, out]      PLIST_ENTRY           SourceList,
  [in]           PKSPIN_LOCK           SourceLock,
  [in, out]      PLIST_ENTRY           DestinationList,
  [in, optional] PKSPIN_LOCK           DestinationLock,
  [in]           KSLIST_ENTRY_LOCATION ListLocation,
  [in]           PFNKSIRPLISTCALLBACK  ListCallback,
  [in]           PVOID                 Context
);

Parameters

[in, out] SourceList

Specifies the head of the queue from which to remove the IRPs.

[in] SourceLock

Pointer to the driver's spin lock for source queue access.

[in, out] DestinationList

Specifies the head of the queue on which to add the IRPs.

[in, optional] DestinationLock

Optionally contains a pointer to driver's spin lock for destination queue access. If this is not provided, the SourceLock parameter is assumed to control both queues. If provided, this lock is always acquired after the SourceLock parameter. If the destination list has a separate spin lock, the system-wide Cancel Spin Lock is first acquired in order to move IRPs and allow the KSQUEUE_SPINLOCK_IRP_STORAGE() spin lock to be updated.

[in] ListLocation

Indicates whether the IRPs should be enumerated from the head or the tail of the source queue. Any IRPs that are moved are placed on the destination queue's opposite end so that ordering is maintained.

[in] ListCallback

Specifies the minidriver-defined KStrIrpListCallback function to call to indicate whether a specific IRP should be moved from SourceList to DestinationList, or if enumeration should be terminated.

[in] Context

Context passed to ListCallback.

Return value

Returns STATUS_SUCCESS if the list was completely enumerated; otherwise, returns any warning or error returned by the minidriver-defined KStrIrpListCallback callback function that interrupted enumeration.

Remarks

An IRP is moved if the KStrIrpListCallback function indicates that it should be moved, whether it is currently acquired. If KStrIrpListCallback returns STATUS_SUCCESS, the IRP is moved. If it returns STATUS_NO_MATCH, the IRP is not moved. Any other return warning or error value will terminate enumeration and be returned by the function. The STATUS_NO_MATCH value should not be returned as an error by KStrIrpListCallback. KStrIrpListCallback is called at DISPATCH_LEVEL. KStrIrpListCallback is always called at least once at the end with a NULL IRP value to complete list enumeration.

KsMoveIrpsOnCancelableQueue continues through the list until the callback function indicates that the search should be terminated, or the end of the list is reached. KsMoveIrpsOnCancelableQueue minimizes the use of the system-wide Cancel Spin Lock by using the provided spin locks to synchronize access when possible. KsMoveIrpsOnCancelableQueue does not allow the cancel routine to be modified while moving IRPs.

The function can be called at DISPATCH_LEVEL or lower.

Requirements

Requirement Value
Target Platform Universal
Header ks.h (include Ks.h)
Library Ks.lib

See also

KStrIrpListCallback