FLT_PARAMETERS for IRP_MJ_QUERY_QUOTA union
Union component used when the MajorFunction field of the FLT_IO_PARAMETER_BLOCK structure for the operation is IRP_MJ_QUERY_QUOTA.
Syntax
typedef union _FLT_PARAMETERS {
... ;
struct {
ULONG Length;
PSID StartSid;
PFILE_GET_QUOTA_INFORMATION SidList;
ULONG SidListLength;
PVOID QuotaBuffer;
PMLD MdlAddress;
} QueryQuota;
... ;
} FLT_PARAMETERS, *PFLT_PARAMETERS;
Members
QueryQuota: Structure containing the following members.
Length: Length, in bytes, of the buffer that QuotaBuffer points to.
StartSid: Optional pointer to the security identifier (SID) of the entry at which to begin scanning the quota list. This parameter is ignored if the SL_INDEX_SPECIFIED flag is not set in the FLT_IO_PARAMETER_BLOCK structure for the operation or if SidList points to a nonempty list.
SidList: Pointer to a caller-supplied FILE_GET_QUOTA_INFORMATION-structured input buffer specifying the SIDs whose quota information is to be queried.
SidListLength: Length, in bytes, of the buffer that SidList points to.
QuotaBuffer: Pointer to a caller-supplied FILE_QUOTA_INFORMATION-structured output buffer where the quota information is to be returned. This member is optional and can be NULL if a MDL is provided in MdlAddress. See Remarks.
MdlAddress: Address of a memory descriptor list (MDL) describing the buffer that QuotaBuffer points to. This member is optional and can be NULL if a buffer is provided in QuotaBuffer. See Remarks.
Remarks
The FLT_PARAMETERS structure for IRP_MJ_QUERY_QUOTA operations contains the parameters for an IRP-based query-quota-information operation represented by a callback data (FLT_CALLBACK_DATA) structure. It is contained in an FLT_IO_PARAMETER_BLOCK structure.
If both a QuotaBuffer and MdlAddress buffer are provided, it is recommended that minifilters use the MDL. The memory that QuotaBuffer points to is valid when it is a user mode address being accessed within the context of the calling process, or if it is a kernel mode address.
If a minifilter changes the value of MdlAddress, then after its post operation callback, Filter Manager will free the MDL currently stored in MdlAddress and restore the previous value of MdlAddress.
IRP_MJ_QUERY_QUOTA is an IRP-based operation.
Requirements
| Requirement type | Requirement |
|---|---|
| Header | Fltkernel.h (include Fltkernel.h) |