436 lines
11 KiB
C
436 lines
11 KiB
C
/*++
|
|
|
|
Copyright (c) 1998-2001 Microsoft Corporation
|
|
|
|
Module Name:
|
|
|
|
PpHotSwap.c
|
|
|
|
Abstract:
|
|
|
|
This file implements support for hotswap devices.
|
|
|
|
Author:
|
|
|
|
Adrian J. Oney (AdriaO) Feb 2001
|
|
|
|
Revision History:
|
|
|
|
|
|
--*/
|
|
|
|
#include "pnpmgrp.h"
|
|
#include "pihotswap.h"
|
|
|
|
#ifdef ALLOC_PRAGMA
|
|
#pragma alloc_text(PAGE, PpHotSwapInitRemovalPolicy)
|
|
#pragma alloc_text(PAGE, PpHotSwapUpdateRemovalPolicy)
|
|
#pragma alloc_text(PAGE, PpHotSwapGetDevnodeRemovalPolicy)
|
|
#pragma alloc_text(PAGE, PiHotSwapGetDefaultBusRemovalPolicy)
|
|
#pragma alloc_text(PAGE, PiHotSwapGetDetachableNode)
|
|
#endif
|
|
|
|
|
|
VOID
|
|
PpHotSwapInitRemovalPolicy(
|
|
OUT PDEVICE_NODE DeviceNode
|
|
)
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This function initializes the removal policy information for a device node.
|
|
|
|
Arguments:
|
|
|
|
DeviceNode - DevNode to update policy.
|
|
|
|
Return Value:
|
|
|
|
Nothing.
|
|
|
|
--*/
|
|
{
|
|
PAGED_CODE();
|
|
|
|
DeviceNode->RemovalPolicy = (UCHAR) RemovalPolicyNotDetermined;
|
|
DeviceNode->HardwareRemovalPolicy = (UCHAR) RemovalPolicyNotDetermined;
|
|
}
|
|
|
|
|
|
VOID
|
|
PpHotSwapUpdateRemovalPolicy(
|
|
IN PDEVICE_NODE DeviceNode
|
|
)
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This function updates the removal policy by retrieving the appropriate
|
|
data from the registry or drivers.
|
|
|
|
Arguments:
|
|
|
|
DeviceNode - DevNode to update policy on.
|
|
|
|
Return Value:
|
|
|
|
Nothing.
|
|
|
|
--*/
|
|
{
|
|
NTSTATUS status;
|
|
DEVICE_REMOVAL_POLICY deviceRemovalPolicy, parentPolicy;
|
|
PDEVICE_NODE detachableNode;
|
|
ULONG policyLength, policyCharacteristics;
|
|
|
|
PAGED_CODE();
|
|
|
|
PPDEVNODE_ASSERT_LOCK_HELD(PPL_TREEOP_ALLOW_READS);
|
|
|
|
//
|
|
// First find the detachable node - it holds our policy data, and is
|
|
// special as it may make suggestions.
|
|
//
|
|
PiHotSwapGetDetachableNode(DeviceNode, &detachableNode);
|
|
|
|
//
|
|
// We aren't in fact removable. Finish now.
|
|
//
|
|
if (detachableNode == NULL) {
|
|
|
|
DeviceNode->RemovalPolicy = (UCHAR) RemovalPolicyExpectNoRemoval;
|
|
DeviceNode->HardwareRemovalPolicy = (UCHAR) RemovalPolicyExpectNoRemoval;
|
|
return;
|
|
}
|
|
|
|
//
|
|
// Check the stack for an explicit policy...
|
|
//
|
|
policyCharacteristics =
|
|
((DeviceNode->PhysicalDeviceObject->Characteristics) &
|
|
FILE_CHARACTERISTICS_REMOVAL_POLICY_MASK);
|
|
|
|
if (policyCharacteristics == FILE_CHARACTERISTICS_EXPECT_ORDERLY_REMOVAL) {
|
|
|
|
deviceRemovalPolicy = RemovalPolicyExpectOrderlyRemoval;
|
|
|
|
} else if (policyCharacteristics == FILE_CHARACTERISTICS_EXPECT_SURPRISE_REMOVAL) {
|
|
|
|
deviceRemovalPolicy = RemovalPolicyExpectSurpriseRemoval;
|
|
|
|
} else if (DeviceNode != detachableNode) {
|
|
|
|
//
|
|
// We didn't get any good guesses. Therefore use the weakest policy.
|
|
//
|
|
deviceRemovalPolicy = RemovalPolicyUnspecified;
|
|
|
|
} else {
|
|
|
|
//
|
|
// If we're the detach point, then we win.
|
|
//
|
|
PiHotSwapGetDefaultBusRemovalPolicy(DeviceNode, &deviceRemovalPolicy);
|
|
}
|
|
|
|
if (DeviceNode != detachableNode) {
|
|
|
|
//
|
|
// Do we have a winning policy? There are two possible algorithms for
|
|
// coming to such a decision.
|
|
// 1) Best policy is stored back at the detach point. If a child has a
|
|
// better policy, the detach point is updated.
|
|
// 2) Policy is inherited downwards from the parent.
|
|
//
|
|
// We choose the second algorithm because devnode start orders may
|
|
// change scenario to scenario, and we favor determinism (same results
|
|
// each time) over opportunism (nonmarked child gets write caching
|
|
// enabled only on Tuesdays.)
|
|
//
|
|
parentPolicy = DeviceNode->Parent->RemovalPolicy;
|
|
if (deviceRemovalPolicy > parentPolicy) {
|
|
|
|
//
|
|
// Seems dad was right afterall...
|
|
//
|
|
deviceRemovalPolicy = parentPolicy;
|
|
}
|
|
}
|
|
|
|
//
|
|
// Update the policy hardware policy and the overall policy in case there's
|
|
// no registry override.
|
|
//
|
|
DeviceNode->RemovalPolicy = (UCHAR) deviceRemovalPolicy;
|
|
DeviceNode->HardwareRemovalPolicy = (UCHAR) deviceRemovalPolicy;
|
|
|
|
//
|
|
// We might not have to ask the stack anything. Check for a registry
|
|
// override.
|
|
//
|
|
policyLength = sizeof(DEVICE_REMOVAL_POLICY);
|
|
|
|
status = PiGetDeviceRegistryProperty(
|
|
DeviceNode->PhysicalDeviceObject,
|
|
REG_DWORD,
|
|
REGSTR_VALUE_REMOVAL_POLICY,
|
|
NULL,
|
|
&deviceRemovalPolicy,
|
|
&policyLength
|
|
);
|
|
|
|
//
|
|
// If we have an override, set that as the policy.
|
|
//
|
|
if (NT_SUCCESS(status) &&
|
|
((deviceRemovalPolicy == RemovalPolicyExpectOrderlyRemoval) ||
|
|
(deviceRemovalPolicy == RemovalPolicyExpectSurpriseRemoval))) {
|
|
|
|
DeviceNode->RemovalPolicy = (UCHAR) deviceRemovalPolicy;
|
|
}
|
|
}
|
|
|
|
|
|
VOID
|
|
PpHotSwapGetDevnodeRemovalPolicy(
|
|
IN PDEVICE_NODE DeviceNode,
|
|
IN BOOLEAN IncludeRegistryOverride,
|
|
OUT PDEVICE_REMOVAL_POLICY RemovalPolicy
|
|
)
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This function retrieves the removal policy for a device node.
|
|
|
|
Arguments:
|
|
|
|
DeviceNode - DevNode to retrieve policy from.
|
|
|
|
IncludeRegistryOverride - TRUE if a registry override should be taken into
|
|
account if present. FALSE if the check should be
|
|
restricted to the hardware.
|
|
|
|
RemovalPolicy - Receives removal policy.
|
|
|
|
Return Value:
|
|
|
|
Nothing.
|
|
|
|
--*/
|
|
{
|
|
PDEVICE_NODE detachableNode;
|
|
DEVICE_REMOVAL_POLICY reportedPolicy;
|
|
|
|
PAGED_CODE();
|
|
|
|
//
|
|
// Ensure the tree won't be edited while we examine it.
|
|
//
|
|
PpDevNodeLockTree(PPL_SIMPLE_READ);
|
|
|
|
if (IncludeRegistryOverride) {
|
|
|
|
reportedPolicy = DeviceNode->RemovalPolicy;
|
|
|
|
} else {
|
|
|
|
reportedPolicy = DeviceNode->HardwareRemovalPolicy;
|
|
}
|
|
|
|
if (reportedPolicy == RemovalPolicyNotDetermined) {
|
|
|
|
//
|
|
// We haven't started yet or asked the bus. Our policy is based on
|
|
// whether the device is removable or ejectable.
|
|
//
|
|
PiHotSwapGetDetachableNode(DeviceNode, &detachableNode);
|
|
|
|
if (detachableNode == NULL) {
|
|
|
|
reportedPolicy = RemovalPolicyExpectNoRemoval;
|
|
|
|
} else if (IopDeviceNodeFlagsToCapabilities(detachableNode)->EjectSupported) {
|
|
|
|
//
|
|
// Ejectable devices require orderly removal. We will assume the
|
|
// user knows this.
|
|
//
|
|
reportedPolicy = RemovalPolicyExpectOrderlyRemoval;
|
|
|
|
} else {
|
|
|
|
ASSERT(IopDeviceNodeFlagsToCapabilities(detachableNode)->Removable);
|
|
|
|
//
|
|
// Removal nonstarted devices can be pulled at any instant.
|
|
//
|
|
reportedPolicy = RemovalPolicyExpectSurpriseRemoval;
|
|
}
|
|
|
|
} else {
|
|
|
|
//
|
|
// The devnode has a cached policy. Cut down on the options.
|
|
//
|
|
switch(reportedPolicy) {
|
|
|
|
case RemovalPolicyExpectNoRemoval:
|
|
case RemovalPolicyExpectOrderlyRemoval:
|
|
case RemovalPolicyExpectSurpriseRemoval:
|
|
//
|
|
// Leave unchanged.
|
|
//
|
|
break;
|
|
|
|
case RemovalPolicySuggestSurpriseRemoval:
|
|
reportedPolicy = RemovalPolicyExpectSurpriseRemoval;
|
|
break;
|
|
|
|
default:
|
|
ASSERT(0);
|
|
|
|
//
|
|
// Fall through.
|
|
//
|
|
|
|
case RemovalPolicyUnspecified:
|
|
|
|
//
|
|
// Unspecified is treated as orderly since the diversity of
|
|
// busses favor high-speed orderly connections over consumer
|
|
// connections.
|
|
//
|
|
// Fall through
|
|
//
|
|
|
|
case RemovalPolicySuggestOrderlyRemoval:
|
|
reportedPolicy = RemovalPolicyExpectOrderlyRemoval;
|
|
break;
|
|
}
|
|
}
|
|
|
|
PpDevNodeUnlockTree(PPL_SIMPLE_READ);
|
|
*RemovalPolicy = reportedPolicy;
|
|
}
|
|
|
|
|
|
VOID
|
|
PiHotSwapGetDefaultBusRemovalPolicy(
|
|
IN PDEVICE_NODE DeviceNode,
|
|
OUT PDEVICE_REMOVAL_POLICY RemovalPolicy
|
|
)
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This function gets the default removal policy for a bus. This should be
|
|
turned into a query in future designs.
|
|
|
|
Arguments:
|
|
|
|
DeviceNode - DevNode to examine. This devnode should be the detach point.
|
|
|
|
RemovalPolicy - Receives removal policy for the node.
|
|
|
|
Return Value:
|
|
|
|
None.
|
|
|
|
--*/
|
|
{
|
|
DEVICE_REMOVAL_POLICY deviceRemovalPolicy;
|
|
|
|
PAGED_CODE();
|
|
|
|
PPDEVNODE_ASSERT_LOCK_HELD(PPL_TREEOP_ALLOW_READS);
|
|
|
|
if ((DeviceNode->InstancePath.Length > 8) &&
|
|
(!_wcsnicmp(DeviceNode->InstancePath.Buffer, L"USB\\", 4))) {
|
|
|
|
deviceRemovalPolicy = RemovalPolicySuggestSurpriseRemoval;
|
|
|
|
} else if ((DeviceNode->InstancePath.Length > 10) &&
|
|
(!_wcsnicmp(DeviceNode->InstancePath.Buffer, L"1394\\", 5))) {
|
|
|
|
deviceRemovalPolicy = RemovalPolicySuggestSurpriseRemoval;
|
|
|
|
} else if ((DeviceNode->InstancePath.Length > 10) &&
|
|
(!_wcsnicmp(DeviceNode->InstancePath.Buffer, L"SBP2\\", 5))) {
|
|
|
|
deviceRemovalPolicy = RemovalPolicySuggestSurpriseRemoval;
|
|
|
|
} else if ((DeviceNode->InstancePath.Length > 14) &&
|
|
(!_wcsnicmp(DeviceNode->InstancePath.Buffer, L"PCMCIA\\", 7))) {
|
|
|
|
deviceRemovalPolicy = RemovalPolicySuggestSurpriseRemoval;
|
|
|
|
} else if ((DeviceNode->InstancePath.Length > 8) &&
|
|
(!_wcsnicmp(DeviceNode->InstancePath.Buffer, L"PCI\\", 4)) &&
|
|
(DeviceNode->Parent->ServiceName.Length == 12) &&
|
|
(!_wcsicmp(DeviceNode->Parent->ServiceName.Buffer, L"PCMCIA"))) {
|
|
|
|
deviceRemovalPolicy = RemovalPolicySuggestSurpriseRemoval;
|
|
|
|
} else {
|
|
|
|
deviceRemovalPolicy = RemovalPolicySuggestOrderlyRemoval;
|
|
}
|
|
|
|
*RemovalPolicy = deviceRemovalPolicy;
|
|
}
|
|
|
|
|
|
VOID
|
|
PiHotSwapGetDetachableNode(
|
|
IN PDEVICE_NODE DeviceNode,
|
|
OUT PDEVICE_NODE *DetachableNode
|
|
)
|
|
/*++
|
|
|
|
Routine Description:
|
|
|
|
This function starts at the DeviceNode and walks up the tree to find the
|
|
first node that is removable.
|
|
|
|
Arguments:
|
|
|
|
DeviceNode - DevNode to start walk from.
|
|
|
|
DetachableNode - Receives detachable node, NULL if none.
|
|
|
|
Return Value:
|
|
|
|
Nothing.
|
|
|
|
--*/
|
|
{
|
|
PDEVICE_NODE currentNode;
|
|
|
|
PAGED_CODE();
|
|
|
|
PPDEVNODE_ASSERT_LOCK_HELD(PPL_SIMPLE_READ);
|
|
|
|
//
|
|
// We haven't started yet or asked the bus. Our policy is based on
|
|
// whether the device is removable or ejectable.
|
|
//
|
|
for(currentNode = DeviceNode;
|
|
currentNode != NULL;
|
|
currentNode = currentNode->Parent) {
|
|
|
|
if ((IopDeviceNodeFlagsToCapabilities(currentNode)->Removable) ||
|
|
(IopDeviceNodeFlagsToCapabilities(currentNode)->EjectSupported)) {
|
|
|
|
break;
|
|
}
|
|
}
|
|
|
|
*DetachableNode = currentNode;
|
|
}
|
|
|
|
|
|
|
|
|