Windows2000/private/ntos/io/complete.c

517 lines
22 KiB
C

/*++
Copyright (c) 1994 Microsoft Corporation
Module Name:
complete.c
Abstract:
This module implements the executive I/O completion object. Functions are
provided to create, open, query, and wait for I/O completion objects.
Author:
David N. Cutler (davec) 25-Feb-1994
Environment:
Kernel mode only.
--*/
#include "iop.h"
// Define forward referenced function prototypes.
VOID IopFreeMiniPacket (PIOP_MINI_COMPLETION_PACKET MiniPacket);
// Define section types for appropriate functions.
#ifdef ALLOC_PRAGMA
#pragma alloc_text(PAGE, NtCreateIoCompletion)
#pragma alloc_text(PAGE, NtOpenIoCompletion)
#pragma alloc_text(PAGE, NtQueryIoCompletion)
#pragma alloc_text(PAGE, NtRemoveIoCompletion)
#pragma alloc_text(PAGE, NtSetIoCompletion)
#pragma alloc_text(PAGE, IoSetIoCompletion)
#endif
NTSTATUS NtCreateIoCompletion (
IN PHANDLE IoCompletionHandle,
IN ACCESS_MASK DesiredAccess,
IN POBJECT_ATTRIBUTES ObjectAttributes OPTIONAL,
IN ULONG Count OPTIONAL
)
/*++
Routine Description:
This function creates an I/O completion object, sets the maximum target concurrent thread count to the specified value,
and opens a handle to the object with the specified desired access.
Arguments:
IoCompletionHandle - Supplies a pointer to a variable that receives the I/O completion object handle.
DesiredAccess - Supplies the desired types of access for the I/O completion object.
ObjectAttributes - Supplies a pointer to an object attributes structure.
Count - Supplies the target maximum number of threads that should be concurrently active.
If this parameter is not specified, then the number of processors is used.
Return Value:
STATUS_SUCCESS is returned if the function is success. Otherwise, an error status is returned.
--*/
{
HANDLE Handle;
KPROCESSOR_MODE PreviousMode;
PVOID IoCompletion;
NTSTATUS Status;
// Establish an exception handler, probe the output handle address, and attempt to create an I/O completion object.
// If the probe fails, then return the exception code as the service status.
// Otherwise, return the status value returned by the object insertion routine.
try {
// Get previous processor mode and probe output handle address if necessary.
PreviousMode = KeGetPreviousMode();
if (PreviousMode != KernelMode) {
ProbeForWriteHandle(IoCompletionHandle);
}
// Allocate I/O completion object.
Status = ObCreateObject(PreviousMode,
IoCompletionObjectType,
ObjectAttributes,
PreviousMode,
NULL,
sizeof(KQUEUE),
0,
0,
(PVOID *)&IoCompletion);
// If the I/O completion object was successfully allocated, then
// initialize the object and attempt to insert it in the handle table of the current process.
if (NT_SUCCESS(Status)) {
KeInitializeQueue((PKQUEUE)IoCompletion, Count);
Status = ObInsertObject(IoCompletion, NULL, DesiredAccess, 0, (PVOID *)NULL, &Handle);
// If the I/O completion object was successfully inserted in the handle table of the current process, then attempt to write the handle value.
// If the write attempt fails, then do not report an error.
// When the caller attempts to access the handle value, an access violation will occur.
if (NT_SUCCESS(Status)) {
try {
*IoCompletionHandle = Handle;
} except(ExSystemExceptionFilter()) {
NOTHING;
}
}
}
} except(ExSystemExceptionFilter()) {// If an exception occurs during the probe of the output handle address,
Status = GetExceptionCode();// then always handle the exception and return the exception code as the status value.
}
return Status;// Return service status.
}
NTSTATUS NtOpenIoCompletion (OUT PHANDLE IoCompletionHandle, IN ACCESS_MASK DesiredAccess, IN POBJECT_ATTRIBUTES ObjectAttributes)
/*++
Routine Description:
This function opens a handle to an I/O completion object with the specified desired access.
Arguments:
IoCompletionHandle - Supplies a pointer to a variable that receives the completion object handle.
DesiredAccess - Supplies the desired types of access for the I/O completion object.
ObjectAttributes - Supplies a pointer to an object attributes structure.
Return Value:
STATUS_SUCCESS is returned if the function is success. Otherwise, an error status is returned.
--*/
{
HANDLE Handle;
KPROCESSOR_MODE PreviousMode;
NTSTATUS Status;
// Establish an exception handler, probe the output handle address, and attempt to open an I/O completion object.
// If the probe fails, then return the exception code as the service status.
// Otherwise, return the status value returned by the object open routine.
try {
// Get previous processor mode and probe output handle address if necessary.
PreviousMode = KeGetPreviousMode();
if (PreviousMode != KernelMode) {
ProbeForWriteHandle(IoCompletionHandle);
}
// Open handle to the completion object with the specified desired access.
Status = ObOpenObjectByName(ObjectAttributes, IoCompletionObjectType, PreviousMode, NULL, DesiredAccess, NULL, &Handle);
// If the open was successful, then attempt to write the I/O completion object handle value.
// If the write attempt fails, then do not report an error.
// When the caller attempts to access the handle value, an access violation will occur.
if (NT_SUCCESS(Status)) {
try {
*IoCompletionHandle = Handle;
} except(ExSystemExceptionFilter()) {
NOTHING;
}
}
} except(ExSystemExceptionFilter()) {// If an exception occurs during the probe of the output handle address,
Status = GetExceptionCode();// then always handle the exception and return the exception code as the status value.
}
return Status;// Return service status.
}
NTSTATUS NtQueryIoCompletion (
IN HANDLE IoCompletionHandle,
IN IO_COMPLETION_INFORMATION_CLASS IoCompletionInformationClass,
OUT PVOID IoCompletionInformation,
IN ULONG IoCompletionInformationLength,
OUT PULONG ReturnLength OPTIONAL
)
/*++
Routine Description:
This function queries the state of an I/O completion object and returns the requested information in the specified record structure.
Arguments:
IoCompletionHandle - Supplies a handle to an I/O completion object.
IoCompletionInformationClass - Supplies the class of information being requested.
IoCompletionInformation - Supplies a pointer to a record that receives the requested information.
IoCompletionInformationLength - Supplies the length of the record that receives the requested information.
ReturnLength - Supplies an optional pointer to a variable that receives the actual length of the information that is returned.
Return Value:
STATUS_SUCCESS is returned if the function is success. Otherwise, an error status is returned.
--*/
{
PVOID IoCompletion;
LONG Depth;
KPROCESSOR_MODE PreviousMode;
NTSTATUS Status;
// Establish an exception handler, probe the output arguments, reference the I/O completion object, and return the specified information.
// If the probe fails, then return the exception code as the service status.
// Otherwise return the status value returned by the reference object by handle routine.
try {
// Get previous processor mode and probe output arguments if necessary.
PreviousMode = KeGetPreviousMode();
if (PreviousMode != KernelMode) {
ProbeForWrite(IoCompletionInformation, sizeof(IO_COMPLETION_BASIC_INFORMATION), sizeof(ULONG));
if (ARGUMENT_PRESENT(ReturnLength)) {
ProbeForWriteUlong(ReturnLength);
}
}
// Check argument validity.
if (IoCompletionInformationClass != IoCompletionBasicInformation) {
return STATUS_INVALID_INFO_CLASS;
}
if (IoCompletionInformationLength != sizeof(IO_COMPLETION_BASIC_INFORMATION)) {
return STATUS_INFO_LENGTH_MISMATCH;
}
// Reference the I/O completion object by handle.
Status = ObReferenceObjectByHandle(IoCompletionHandle, IO_COMPLETION_QUERY_STATE, IoCompletionObjectType, PreviousMode, &IoCompletion, NULL);
// If the reference was successful, then read the current state of the I/O completion object, dereference the I/O completion object,
// fill in the information structure, and return the structure length if specified.
// If the write of the I/O completion information or the return length fails, then do not report an error.
// When the caller accesses the information structure or length an access violation will occur.
if (NT_SUCCESS(Status)) {
Depth = KeReadStateQueue((PKQUEUE)IoCompletion);
ObDereferenceObject(IoCompletion);
try {
((PIO_COMPLETION_BASIC_INFORMATION)IoCompletionInformation)->Depth = Depth;
if (ARGUMENT_PRESENT(ReturnLength)) {
*ReturnLength = sizeof(IO_COMPLETION_BASIC_INFORMATION);
}
} except(ExSystemExceptionFilter()) {
NOTHING;
}
}
} except(ExSystemExceptionFilter()) {// If an exception occurs during the probe of the output arguments,
Status = GetExceptionCode();// then always handle the exception and return the exception code as the status value.
}
return Status;// Return service status.
}
NTSTATUS NtSetIoCompletion (
IN HANDLE IoCompletionHandle,
IN PVOID KeyContext,
IN PVOID ApcContext,
IN NTSTATUS IoStatus,
IN ULONG_PTR IoStatusInformation
)
/*++
Routine Description:
This function allows the caller to queue an Irp to an I/O completion
port and specify all of the information that is returned out the other end using NtRemoveIoCompletion.
Arguments:
IoCompletionHandle - Supplies a handle to the io completion port that the caller intends to queue a completion packet to
KeyContext - Supplies the key context that is returned during a call to NtRemoveIoCompletion
ApcContext - Supplies the apc context that is returned during a call to NtRemoveIoCompletion
IoStatus - Supplies the IoStatus->Status data that is returned during a call to NtRemoveIoCompletion
IoStatusInformation - Supplies the IoStatus->Information data that is returned during a call to NtRemoveIoCompletion
Return Value:
STATUS_SUCCESS is returned if the function is success. Otherwise, an error status is returned.
--*/
{
PVOID IoCompletion;
PIOP_MINI_COMPLETION_PACKET MiniPacket;
NTSTATUS Status;
PAGED_CODE();
Status = ObReferenceObjectByHandle(IoCompletionHandle, IO_COMPLETION_MODIFY_STATE, IoCompletionObjectType, KeGetPreviousMode(), &IoCompletion, NULL);
if (NT_SUCCESS(Status)) {
Status = IoSetIoCompletion(IoCompletion, KeyContext, ApcContext, IoStatus, IoStatusInformation, TRUE);
ObDereferenceObject(IoCompletion);
}
return Status;
}
NTSTATUS NtRemoveIoCompletion (
IN HANDLE IoCompletionHandle,
OUT PVOID *KeyContext,
OUT PVOID *ApcContext,
OUT PIO_STATUS_BLOCK IoStatusBlock,
IN PLARGE_INTEGER Timeout OPTIONAL)
/*++
Routine Description:
This function removes an entry from an I/O completion object.
If there are currently no entries available, then the calling thread waits for an entry.
Arguments:
Completion - Supplies a handle to an I/O completion object.
KeyContext - Supplies a pointer to a variable that receives the key context that was specified when the I/O completion object was assoicated with a file object.
ApcContext - Supplies a pointer to a variable that receives the context that was specified when the I/O operation was issued.
IoStatus - Supplies a pointer to a variable that receives the I/O completion status.
Timeout - Supplies a pointer to an optional time out value.
Return Value:
STATUS_SUCCESS is returned if the function is success. Otherwise, an error status is returned.
--*/
{
PLARGE_INTEGER CapturedTimeout;
PLIST_ENTRY Entry;
PVOID IoCompletion;
PIRP Irp;
KPROCESSOR_MODE PreviousMode;
NTSTATUS Status;
LARGE_INTEGER TimeoutValue;
PVOID LocalApcContext;
PVOID LocalKeyContext;
IO_STATUS_BLOCK LocalIoStatusBlock;
PIOP_MINI_COMPLETION_PACKET MiniPacket;
// Establish an exception handler, probe the I/O context, the I/O status, and the optional timeout value if specified, reference
// the I/O completion object, and attempt to remove an entry from the I/O completion object.
// If the probe fails, then return the exception code as the service status.
// Otherwise, return a value dependent on the outcome of the queue removal.
try {
// Get previous processor mode and probe the I/O context, status, and timeout if necessary.
CapturedTimeout = NULL;
PreviousMode = KeGetPreviousMode();
if (PreviousMode != KernelMode) {
ProbeForWriteUlong_ptr((PULONG_PTR)ApcContext);
ProbeForWriteUlong_ptr((PULONG_PTR)KeyContext);
ProbeForWriteIoStatus(IoStatusBlock);
if (ARGUMENT_PRESENT(Timeout)) {
CapturedTimeout = &TimeoutValue;
TimeoutValue = ProbeAndReadLargeInteger(Timeout);
}
} else{
if (ARGUMENT_PRESENT(Timeout)) {
CapturedTimeout = Timeout;
}
}
// Reference the I/O completion object by handle.
Status = ObReferenceObjectByHandle(IoCompletionHandle, IO_COMPLETION_MODIFY_STATE, IoCompletionObjectType, PreviousMode, &IoCompletion, NULL);
// If the reference was successful, then attempt to remove an entry from the I/O completion object.
// If an entry is removed from the I/O completion object, then capture the completion information,
// release the associated IRP, and attempt to write the completion inforamtion.
// If the write of the completion infomation fails, then do not report an error.
// When the caller attempts to access the completion information, an access violation will occur.
if (NT_SUCCESS(Status)) {
Entry = KeRemoveQueue((PKQUEUE)IoCompletion, PreviousMode, CapturedTimeout);
// N.B. The entry value returned can be the address of a list entry, STATUS_USER_APC, or STATUS_TIMEOUT.
if (((LONG_PTR)Entry == STATUS_TIMEOUT) || ((LONG_PTR)Entry == STATUS_USER_APC)) {
Status = (NTSTATUS)((LONG_PTR)Entry);
} else {
// Set the completion status, capture the completion information, deallocate the associated IRP,
// and attempt to write the completion information.
Status = STATUS_SUCCESS;
try {
MiniPacket = CONTAINING_RECORD(Entry, IOP_MINI_COMPLETION_PACKET, ListEntry);
if ( MiniPacket->PacketType == IopCompletionPacketIrp ) {
Irp = CONTAINING_RECORD(Entry, IRP, Tail.Overlay.ListEntry);
LocalApcContext = Irp->Overlay.AsynchronousParameters.UserApcContext;
LocalKeyContext = (PVOID)Irp->Tail.CompletionKey;
LocalIoStatusBlock = Irp->IoStatus;
IoFreeIrp(Irp);
} else {
LocalApcContext = MiniPacket->ApcContext;
LocalKeyContext = (PVOID)MiniPacket->KeyContext;
LocalIoStatusBlock.Status = MiniPacket->IoStatus;
LocalIoStatusBlock.Information = MiniPacket->IoStatusInformation;
IopFreeMiniPacket(MiniPacket);
}
*ApcContext = LocalApcContext;
*KeyContext = LocalKeyContext;
*IoStatusBlock = LocalIoStatusBlock;
} except(ExSystemExceptionFilter()) {
NOTHING;
}
}
ObDereferenceObject(IoCompletion);// Deference I/O completion object.
}
} except(ExSystemExceptionFilter()) {// If an exception occurs during the probe of the previous count,
Status = GetExceptionCode();// then always handle the exception and return the exception code as the status value.
}
return Status;// Return service status.
}
NTKERNELAPI NTSTATUS IoSetIoCompletion (
IN PVOID IoCompletion,
IN PVOID KeyContext,
IN PVOID ApcContext,
IN NTSTATUS IoStatus,
IN ULONG_PTR IoStatusInformation,
IN BOOLEAN Quota
)
/*++
Routine Description:
This function allows the caller to queue an Irp to an I/O completion port and specify all of the information that is returned out the other
end using NtRemoveIoCompletion.
Arguments:
IoCompletion - Supplies a a pointer to the completion port that the caller intends to queue a completion packet to.
KeyContext - Supplies the key context that is returned during a call to NtRemoveIoCompletion.
ApcContext - Supplies the apc context that is returned during a call to NtRemoveIoCompletion.
IoStatus - Supplies the IoStatus->Status data that is returned during a call to NtRemoveIoCompletion.
IoStatusInformation - Supplies the IoStatus->Information data that is returned during a call to NtRemoveIoCompletion.
Return Value:
STATUS_SUCCESS is returned if the function is success. Otherwise, an error status is returned.
--*/
{
PNPAGED_LOOKASIDE_LIST Lookaside;
PIOP_MINI_COMPLETION_PACKET MiniPacket;
ULONG PacketType;
PKPRCB Prcb;
NTSTATUS Status = STATUS_SUCCESS;
PAGED_CODE();
// Attempt to allocate the minpacket from the per processor lookaside list.
PacketType = IopCompletionPacketMini;
Prcb = KeGetCurrentPrcb();
Lookaside = Prcb->PPLookasideList[LookasideCompletionList].P;
Lookaside->L.TotalAllocates += 1;
MiniPacket = (PVOID)ExInterlockedPopEntrySList(&Lookaside->L.ListHead, &Lookaside->Lock);
// If the per processor lookaside list allocation failed, then attempt to allocate from the system lookaside list.
if (MiniPacket == NULL) {
Lookaside->L.AllocateMisses += 1;
Lookaside = Prcb->PPLookasideList[LookasideCompletionList].L;
Lookaside->L.TotalAllocates += 1;
MiniPacket = (PVOID)ExInterlockedPopEntrySList(&Lookaside->L.ListHead, &Lookaside->Lock);
}
// If both lookaside allocation attempts failed, then attempt to allocate from pool.
if (MiniPacket == NULL) {
Lookaside->L.AllocateMisses += 1;
// If quota is specified, then allocate pool with quota charged.
// Otherwise, allocate pool without quota.
if (Quota != FALSE) {
PacketType = IopCompletionPacketQuota;
try {
MiniPacket = ExAllocatePoolWithQuotaTag(NonPagedPool, sizeof(*MiniPacket), ' pcI');
} except(EXCEPTION_EXECUTE_HANDLER) {
NOTHING;
}
} else {
MiniPacket = ExAllocatePoolWithTag(NonPagedPool, sizeof(*MiniPacket), ' pcI');
}
}
// If a minipacket was successfully allocated, then initialize and queue the packet to the specified I/O completion queue.
if (MiniPacket != NULL) {
MiniPacket->PacketType = PacketType;
MiniPacket->KeyContext = KeyContext;
MiniPacket->ApcContext = ApcContext;
MiniPacket->IoStatus = IoStatus;
MiniPacket->IoStatusInformation = IoStatusInformation;
KeInsertQueue((PKQUEUE)IoCompletion, &MiniPacket->ListEntry);
} else {
Status = STATUS_INSUFFICIENT_RESOURCES;
}
return Status;
}
VOID IopFreeMiniPacket (PIOP_MINI_COMPLETION_PACKET MiniPacket)
/*++
Routine Description:
This function free the specefied I/O completion packet.
Arguments:
MiniPacket - Supplies a pointer to an I/O completion minipacket.
--*/
{
PNPAGED_LOOKASIDE_LIST Lookaside;
PKPRCB Prcb;
// If the minipacket cannot be returned to either the per processor or system lookaside list, then free the minipacket to pool.
// Otherwise, release the quota if quota was allocated and push the entry onto one of the lookaside lists.
Prcb = KeGetCurrentPrcb();
Lookaside = Prcb->PPLookasideList[LookasideCompletionList].P;
Lookaside->L.TotalFrees += 1;
if (ExQueryDepthSList(&Lookaside->L.ListHead) >= Lookaside->L.Depth) {
Lookaside->L.FreeMisses += 1;
Lookaside = Prcb->PPLookasideList[LookasideCompletionList].L;
Lookaside->L.TotalFrees += 1;
if (ExQueryDepthSList(&Lookaside->L.ListHead) >= Lookaside->L.Depth) {
Lookaside->L.FreeMisses += 1;
ExFreePool(MiniPacket);
} else {
if (MiniPacket->PacketType == IopCompletionPacketQuota) {
ExReturnPoolQuota(MiniPacket);
}
ExInterlockedPushEntrySList(&Lookaside->L.ListHead, (PSINGLE_LIST_ENTRY)MiniPacket, &Lookaside->Lock);
}
} else {
if (MiniPacket->PacketType == IopCompletionPacketQuota) {
ExReturnPoolQuota(MiniPacket);
}
ExInterlockedPushEntrySList(&Lookaside->L.ListHead, (PSINGLE_LIST_ENTRY)MiniPacket, &Lookaside->Lock);
}
}
VOID IopDeleteIoCompletion (IN PVOID Object)
/*++
Routine Description:
This function is the delete routine for I/O completion objects.
Its function is to release all the entries in the repsective completion queue and to rundown all threads that are current associated.
Arguments:
Object - Supplies a pointer to an executive I/O completion object.
--*/
{
PLIST_ENTRY FirstEntry;
PIRP Irp;
PLIST_ENTRY NextEntry;
PIOP_MINI_COMPLETION_PACKET MiniPacket;
// Rundown threads associated with the I/O completion object and get the list of unprocessed I/O completion IRPs.
FirstEntry = KeRundownQueue((PKQUEUE)Object);
if (FirstEntry != NULL) {
NextEntry = FirstEntry;
do {
MiniPacket = CONTAINING_RECORD(NextEntry, IOP_MINI_COMPLETION_PACKET, ListEntry);
NextEntry = NextEntry->Flink;
if (MiniPacket->PacketType == IopCompletionPacketIrp) {
Irp = CONTAINING_RECORD(MiniPacket, IRP, Tail.Overlay.ListEntry);
IoFreeIrp(Irp);
} else {
IopFreeMiniPacket(MiniPacket);
}
} while (FirstEntry != NextEntry);
}
}