reactos/ntoskrnl/mm/ARM3/vadnode.c
2019-04-22 17:41:17 +02:00

880 lines
28 KiB
C

/*
* PROJECT: ReactOS Kernel
* LICENSE: BSD - See COPYING.ARM in the top level directory
* FILE: ntoskrnl/mm/ARM3/vadnode.c
* PURPOSE: ARM Memory Manager VAD Node Algorithms
* PROGRAMMERS: ReactOS Portable Systems Group
* Timo Kreuzer (timo.kreuzer@reactos.org)
*/
/* INCLUDES *******************************************************************/
#include <ntoskrnl.h>
#define NDEBUG
#include <debug.h>
#define MODULE_INVOLVED_IN_ARM3
#include <mm/ARM3/miarm.h>
/* Include Mm version of AVL support */
#include "miavl.h"
#include <sdk/lib/rtl/avlsupp.c>
/* GLOBALS ********************************************************************/
CHAR MmReadWrite[32] =
{
MM_NO_ACCESS_ALLOWED, MM_READ_ONLY_ALLOWED, MM_READ_ONLY_ALLOWED,
MM_READ_ONLY_ALLOWED, MM_READ_WRITE_ALLOWED, MM_READ_WRITE_ALLOWED,
MM_READ_WRITE_ALLOWED, MM_READ_WRITE_ALLOWED,
MM_NO_ACCESS_ALLOWED, MM_READ_ONLY_ALLOWED, MM_READ_ONLY_ALLOWED,
MM_READ_ONLY_ALLOWED, MM_READ_WRITE_ALLOWED, MM_READ_WRITE_ALLOWED,
MM_READ_WRITE_ALLOWED, MM_READ_WRITE_ALLOWED,
MM_NO_ACCESS_ALLOWED, MM_READ_ONLY_ALLOWED, MM_READ_ONLY_ALLOWED,
MM_READ_ONLY_ALLOWED, MM_READ_WRITE_ALLOWED, MM_READ_WRITE_ALLOWED,
MM_READ_WRITE_ALLOWED, MM_READ_WRITE_ALLOWED,
MM_NO_ACCESS_ALLOWED, MM_READ_ONLY_ALLOWED, MM_READ_ONLY_ALLOWED,
MM_READ_ONLY_ALLOWED, MM_READ_WRITE_ALLOWED, MM_READ_WRITE_ALLOWED,
MM_READ_WRITE_ALLOWED, MM_READ_WRITE_ALLOWED,
};
/* FUNCTIONS ******************************************************************/
PMMVAD
NTAPI
MiLocateAddress(IN PVOID VirtualAddress)
{
PMMVAD FoundVad;
ULONG_PTR Vpn;
PMM_AVL_TABLE Table = &PsGetCurrentProcess()->VadRoot;
TABLE_SEARCH_RESULT SearchResult;
/* Start with the the hint */
FoundVad = (PMMVAD)Table->NodeHint;
if (!FoundVad) return NULL;
/* Check if this VPN is in the hint, if so, use it */
Vpn = (ULONG_PTR)VirtualAddress >> PAGE_SHIFT;
if ((Vpn >= FoundVad->StartingVpn) && (Vpn <= FoundVad->EndingVpn)) return FoundVad;
/* VAD hint didn't work, go look for it */
SearchResult = RtlpFindAvlTableNodeOrParent(Table,
(PVOID)Vpn,
(PMMADDRESS_NODE*)&FoundVad);
if (SearchResult != TableFoundNode) return NULL;
/* We found it, update the hint */
ASSERT(FoundVad != NULL);
ASSERT((Vpn >= FoundVad->StartingVpn) && (Vpn <= FoundVad->EndingVpn));
Table->NodeHint = FoundVad;
return FoundVad;
}
TABLE_SEARCH_RESULT
NTAPI
MiCheckForConflictingNode(IN ULONG_PTR StartVpn,
IN ULONG_PTR EndVpn,
IN PMM_AVL_TABLE Table,
OUT PMMADDRESS_NODE *NodeOrParent)
{
PMMADDRESS_NODE ParentNode, CurrentNode;
/* If the tree is empty, there is no conflict */
if (Table->NumberGenericTableElements == 0) return TableEmptyTree;
/* Start looping from the root node */
CurrentNode = RtlRightChildAvl(&Table->BalancedRoot);
ASSERT(CurrentNode != NULL);
while (CurrentNode)
{
ParentNode = CurrentNode;
/* This address comes after */
if (StartVpn > CurrentNode->EndingVpn)
{
/* Keep searching on the right */
CurrentNode = RtlRightChildAvl(CurrentNode);
}
else if (EndVpn < CurrentNode->StartingVpn)
{
/* This address ends before the node starts, search on the left */
CurrentNode = RtlLeftChildAvl(CurrentNode);
}
else
{
/* This address is part of this node, return it */
*NodeOrParent = ParentNode;
return TableFoundNode;
}
}
/* There is no more child, save the current node as parent */
*NodeOrParent = ParentNode;
if (StartVpn > ParentNode->EndingVpn)
{
return TableInsertAsRight;
}
else
{
return TableInsertAsLeft;
}
}
VOID
NTAPI
MiInsertNode(IN PMM_AVL_TABLE Table,
IN PMMADDRESS_NODE NewNode,
IN PMMADDRESS_NODE Parent,
IN TABLE_SEARCH_RESULT Result)
{
PMMVAD_LONG Vad;
/* Insert it into the tree */
RtlpInsertAvlTreeNode(Table, NewNode, Parent, Result);
/* Now insert an ARM3 MEMORY_AREA for this node, unless the insert was already from the MEMORY_AREA code */
Vad = (PMMVAD_LONG)NewNode;
if (Vad->u.VadFlags.Spare == 0)
{
NTSTATUS Status;
PMEMORY_AREA MemoryArea;
SIZE_T Size;
PEPROCESS Process = CONTAINING_RECORD(Table, EPROCESS, VadRoot);
PVOID AllocatedBase = (PVOID)(Vad->StartingVpn << PAGE_SHIFT);
Size = ((Vad->EndingVpn + 1) - Vad->StartingVpn) << PAGE_SHIFT;
if (AllocatedBase == NULL)
{
AllocatedBase = (PVOID)(ULONG_PTR)1;
Size -= 1;
}
Status = MmCreateMemoryArea(&Process->Vm,
MEMORY_AREA_OWNED_BY_ARM3,
&AllocatedBase,
Size,
PAGE_READWRITE,
&MemoryArea,
0,
PAGE_SIZE);
ASSERT(NT_SUCCESS(Status));
/* Check if this is VM VAD */
if (Vad->ControlArea == NULL)
{
/* We store the reactos MEMORY_AREA here */
Vad->FirstPrototypePte = (PMMPTE)MemoryArea;
}
else
{
/* This is a section VAD. Store the MAREA here for now */
ASSERT(Vad->u4.Banked == (PVOID)(ULONG_PTR)0xDEADBABEDEADBABEULL);
Vad->u4.Banked = (PVOID)MemoryArea;
}
}
}
VOID
NTAPI
MiInsertVad(IN PMMVAD Vad,
IN PMM_AVL_TABLE VadRoot)
{
TABLE_SEARCH_RESULT Result;
PMMADDRESS_NODE Parent = NULL;
/* Validate the VAD and set it as the current hint */
ASSERT(Vad->EndingVpn >= Vad->StartingVpn);
VadRoot->NodeHint = Vad;
/* Find the parent VAD and where this child should be inserted */
Result = RtlpFindAvlTableNodeOrParent(VadRoot, (PVOID)Vad->StartingVpn, &Parent);
ASSERT(Result != TableFoundNode);
ASSERT((Parent != NULL) || (Result == TableEmptyTree));
/* Do the actual insert operation */
MiInsertNode(VadRoot, (PVOID)Vad, Parent, Result);
}
NTSTATUS
NTAPI
MiInsertVadEx(
_Inout_ PMMVAD Vad,
_In_ ULONG_PTR *BaseAddress,
_In_ SIZE_T ViewSize,
_In_ ULONG_PTR HighestAddress,
_In_ ULONG_PTR Alignment,
_In_ ULONG AllocationType)
{
ULONG_PTR StartingAddress, EndingAddress;
PEPROCESS CurrentProcess;
PETHREAD CurrentThread;
TABLE_SEARCH_RESULT Result;
PMMADDRESS_NODE Parent;
/* Align the view size to pages */
ViewSize = ALIGN_UP_BY(ViewSize, PAGE_SIZE);
/* Get the current process */
CurrentProcess = PsGetCurrentProcess();
/* Acquire the address creation lock and make sure the process is alive */
KeAcquireGuardedMutex(&CurrentProcess->AddressCreationLock);
if (CurrentProcess->VmDeleted)
{
KeReleaseGuardedMutex(&CurrentProcess->AddressCreationLock);
DPRINT1("The process is dying\n");
return STATUS_PROCESS_IS_TERMINATING;
}
/* Did the caller specify an address? */
if (*BaseAddress == 0)
{
/* Make sure HighestAddress is not too large */
HighestAddress = min(HighestAddress, (ULONG_PTR)MM_HIGHEST_VAD_ADDRESS);
/* Which way should we search? */
if ((AllocationType & MEM_TOP_DOWN) || CurrentProcess->VmTopDown)
{
/* Find an address top-down */
Result = MiFindEmptyAddressRangeDownTree(ViewSize,
HighestAddress,
Alignment,
&CurrentProcess->VadRoot,
&StartingAddress,
&Parent);
}
else
{
/* Find an address bottom-up */
Result = MiFindEmptyAddressRangeInTree(ViewSize,
Alignment,
&CurrentProcess->VadRoot,
&Parent,
&StartingAddress);
}
/* Get the ending address, which is the last piece we need for the VAD */
EndingAddress = StartingAddress + ViewSize - 1;
/* Check if we found a suitable location */
if ((Result == TableFoundNode) || (EndingAddress > HighestAddress))
{
DPRINT1("Not enough free space to insert this VAD node!\n");
KeReleaseGuardedMutex(&CurrentProcess->AddressCreationLock);
return STATUS_NO_MEMORY;
}
ASSERT(StartingAddress != 0);
ASSERT(StartingAddress < (ULONG_PTR)HighestAddress);
ASSERT(EndingAddress > StartingAddress);
}
else
{
/* Calculate the starting and ending address */
StartingAddress = ALIGN_DOWN_BY(*BaseAddress, Alignment);
EndingAddress = StartingAddress + ViewSize - 1;
/* Make sure it doesn't conflict with an existing allocation */
Result = MiCheckForConflictingNode(StartingAddress >> PAGE_SHIFT,
EndingAddress >> PAGE_SHIFT,
&CurrentProcess->VadRoot,
&Parent);
if (Result == TableFoundNode)
{
DPRINT("Given address conflicts with existing node\n");
KeReleaseGuardedMutex(&CurrentProcess->AddressCreationLock);
return STATUS_CONFLICTING_ADDRESSES;
}
}
/* Now set the VAD address */
Vad->StartingVpn = StartingAddress >> PAGE_SHIFT;
Vad->EndingVpn = EndingAddress >> PAGE_SHIFT;
/* Check if we already need to charge for the pages */
if ((Vad->u.VadFlags.PrivateMemory && Vad->u.VadFlags.MemCommit) ||
(!Vad->u.VadFlags.PrivateMemory &&
(Vad->u.VadFlags.Protection & PAGE_WRITECOPY)))
{
/* Set the commit charge */
Vad->u.VadFlags.CommitCharge = ViewSize / PAGE_SIZE;
}
/* Check if the VAD is to be secured */
if (Vad->u2.VadFlags2.OneSecured)
{
/* This *must* be a long VAD! */
ASSERT(Vad->u2.VadFlags2.LongVad);
/* Yeah this is retarded, I didn't invent it! */
((PMMVAD_LONG)Vad)->u3.Secured.StartVpn = StartingAddress;
((PMMVAD_LONG)Vad)->u3.Secured.EndVpn = EndingAddress;
}
/* Lock the working set */
CurrentThread = PsGetCurrentThread();
MiLockProcessWorkingSetUnsafe(CurrentProcess, CurrentThread);
/* Insert the VAD */
CurrentProcess->VadRoot.NodeHint = Vad;
MiInsertNode(&CurrentProcess->VadRoot, (PVOID)Vad, Parent, Result);
/* Release the working set */
MiUnlockProcessWorkingSetUnsafe(CurrentProcess, CurrentThread);
/* Update the process' virtual size, and peak virtual size */
CurrentProcess->VirtualSize += ViewSize;
if (CurrentProcess->VirtualSize > CurrentProcess->PeakVirtualSize)
{
CurrentProcess->PeakVirtualSize = CurrentProcess->VirtualSize;
}
/* Unlock the address space */
KeReleaseGuardedMutex(&CurrentProcess->AddressCreationLock);
*BaseAddress = StartingAddress;
return STATUS_SUCCESS;
}
VOID
NTAPI
MiInsertBasedSection(IN PSECTION Section)
{
TABLE_SEARCH_RESULT Result;
PMMADDRESS_NODE Parent = NULL;
ASSERT(Section->Address.EndingVpn >= Section->Address.StartingVpn);
/* Find the parent VAD and where this child should be inserted */
Result = RtlpFindAvlTableNodeOrParent(&MmSectionBasedRoot, (PVOID)Section->Address.StartingVpn, &Parent);
ASSERT(Result != TableFoundNode);
ASSERT((Parent != NULL) || (Result == TableEmptyTree));
MiInsertNode(&MmSectionBasedRoot, &Section->Address, Parent, Result);
}
VOID
NTAPI
MiRemoveNode(IN PMMADDRESS_NODE Node,
IN PMM_AVL_TABLE Table)
{
PMMVAD_LONG Vad;
/* Call the AVL code */
RtlpDeleteAvlTreeNode(Table, Node);
/* Decrease element count */
Table->NumberGenericTableElements--;
/* Check if this node was the hint */
if (Table->NodeHint == Node)
{
/* Get a new hint, unless we're empty now, in which case nothing */
if (!Table->NumberGenericTableElements) Table->NodeHint = NULL;
else Table->NodeHint = Table->BalancedRoot.RightChild;
}
/* Free the node from ReactOS view as well */
Vad = (PMMVAD_LONG)Node;
if ((Table != &MmSectionBasedRoot) && (Vad->u.VadFlags.Spare == 0))
{
PMEMORY_AREA MemoryArea;
PEPROCESS Process;
/* Check if this is VM VAD */
if (Vad->ControlArea == NULL)
{
/* We store the ReactOS MEMORY_AREA here */
MemoryArea = (PMEMORY_AREA)Vad->FirstPrototypePte;
}
else
{
/* This is a section VAD. We store the ReactOS MEMORY_AREA here */
MemoryArea = (PMEMORY_AREA)Vad->u4.Banked;
}
/* Make sure one actually still exists */
if (MemoryArea)
{
/* Make sure we have not already freed it */
ASSERT(MemoryArea != (PVOID)(ULONG_PTR)0xDEADBAB1DEADBAB1ULL);
/* Get the process */
Process = CONTAINING_RECORD(Table, EPROCESS, VadRoot);
/* We only create fake memory-areas for ARM3 VADs */
ASSERT(MemoryArea->Type == MEMORY_AREA_OWNED_BY_ARM3);
ASSERT(MemoryArea->Vad == NULL);
/* Free it */
MmFreeMemoryArea(&Process->Vm, MemoryArea, NULL, NULL);
/* Check if this is VM VAD */
if (Vad->ControlArea == NULL)
{
/* Delete the pointer to it */
Vad->FirstPrototypePte = (PVOID)(ULONG_PTR)0xDEADBAB1DEADBAB1ULL;
}
else
{
/* Delete the pointer to it */
Vad->u4.Banked = (PVOID)(ULONG_PTR)0xDEADBAB1DEADBAB1ULL;
}
}
}
}
PMMADDRESS_NODE
NTAPI
MiGetPreviousNode(IN PMMADDRESS_NODE Node)
{
PMMADDRESS_NODE Parent;
/* Get the left child */
if (RtlLeftChildAvl(Node))
{
/* Get right-most child */
Node = RtlLeftChildAvl(Node);
while (RtlRightChildAvl(Node)) Node = RtlRightChildAvl(Node);
return Node;
}
Parent = RtlParentAvl(Node);
ASSERT(Parent != NULL);
while (Parent != Node)
{
/* The parent should be a right child, return the real predecessor */
if (RtlIsRightChildAvl(Node))
{
/* Return it unless it's the root */
if (Parent == RtlParentAvl(Parent)) Parent = NULL;
return Parent;
}
/* Keep lopping until we find our parent */
Node = Parent;
Parent = RtlParentAvl(Node);
}
/* Nothing found */
return NULL;
}
PMMADDRESS_NODE
NTAPI
MiGetNextNode(IN PMMADDRESS_NODE Node)
{
PMMADDRESS_NODE Parent;
/* Get the right child */
if (RtlRightChildAvl(Node))
{
/* Get left-most child */
Node = RtlRightChildAvl(Node);
while (RtlLeftChildAvl(Node)) Node = RtlLeftChildAvl(Node);
return Node;
}
Parent = RtlParentAvl(Node);
ASSERT(Parent != NULL);
while (Parent != Node)
{
/* The parent should be a left child, return the real predecessor */
if (RtlIsLeftChildAvl(Node))
{
/* Return it */
return Parent;
}
/* Keep lopping until we find our parent */
Node = Parent;
Parent = RtlParentAvl(Node);
}
/* Nothing found */
return NULL;
}
TABLE_SEARCH_RESULT
NTAPI
MiFindEmptyAddressRangeInTree(IN SIZE_T Length,
IN ULONG_PTR Alignment,
IN PMM_AVL_TABLE Table,
OUT PMMADDRESS_NODE *PreviousVad,
OUT PULONG_PTR Base)
{
PMMADDRESS_NODE Node, PreviousNode;
ULONG_PTR PageCount, AlignmentVpn, LowVpn, HighestVpn;
ASSERT(Length != 0);
/* Calculate page numbers for the length, alignment, and starting address */
PageCount = BYTES_TO_PAGES(Length);
AlignmentVpn = Alignment >> PAGE_SHIFT;
LowVpn = ALIGN_UP_BY((ULONG_PTR)MM_LOWEST_USER_ADDRESS >> PAGE_SHIFT, AlignmentVpn);
/* Check for kernel mode table (memory areas) */
if (Table->Unused == 1)
{
LowVpn = ALIGN_UP_BY((ULONG_PTR)MmSystemRangeStart >> PAGE_SHIFT, AlignmentVpn);
}
/* Check if the table is empty */
if (Table->NumberGenericTableElements == 0)
{
/* Tree is empty, the candidate address is already the best one */
*Base = LowVpn << PAGE_SHIFT;
return TableEmptyTree;
}
/* Otherwise, follow the leftmost child of the right root node's child */
Node = RtlRightChildAvl(&Table->BalancedRoot);
while (RtlLeftChildAvl(Node)) Node = RtlLeftChildAvl(Node);
/* Start a search to find a gap */
PreviousNode = NULL;
while (Node != NULL)
{
/* Check if the gap below the current node is suitable */
if (Node->StartingVpn >= LowVpn + PageCount)
{
/* There is enough space to add our node */
*Base = LowVpn << PAGE_SHIFT;
/* Can we use the current node as parent? */
if (RtlLeftChildAvl(Node) == NULL)
{
/* Node has no left child, so use it as parent */
*PreviousVad = Node;
return TableInsertAsLeft;
}
else
{
/* Node has a left child, this means that the previous node is
the right-most child of it's left child and can be used as
the parent. In case we use the space before the left-most
node, it's left child must be NULL. */
ASSERT(PreviousNode != NULL);
ASSERT(RtlRightChildAvl(PreviousNode) == NULL);
*PreviousVad = PreviousNode;
return TableInsertAsRight;
}
}
/* The next candidate is above the current node */
if (Node->EndingVpn >= LowVpn)
LowVpn = ALIGN_UP_BY(Node->EndingVpn + 1, AlignmentVpn);
/* Remember the current node and go to the next node */
PreviousNode = Node;
Node = MiGetNextNode(Node);
}
/* We're up to the highest VAD, will this allocation fit above it? */
HighestVpn = ((ULONG_PTR)MM_HIGHEST_VAD_ADDRESS + 1) / PAGE_SIZE;
/* Check for kernel mode table (memory areas) */
if (Table->Unused == 1)
{
HighestVpn = ALIGN_UP_BY((ULONG_PTR)(LONG_PTR)-1 >> PAGE_SHIFT, AlignmentVpn);
}
if (HighestVpn >= LowVpn + PageCount)
{
/* Yes! Use this VAD to store the allocation */
*PreviousVad = PreviousNode;
*Base = LowVpn << PAGE_SHIFT;
return TableInsertAsRight;
}
/* Nyet, there's no free address space for this allocation, so we'll fail */
return TableFoundNode;
}
TABLE_SEARCH_RESULT
NTAPI
MiFindEmptyAddressRangeDownTree(IN SIZE_T Length,
IN ULONG_PTR BoundaryAddress,
IN ULONG_PTR Alignment,
IN PMM_AVL_TABLE Table,
OUT PULONG_PTR Base,
OUT PMMADDRESS_NODE *Parent)
{
PMMADDRESS_NODE Node, OldNode = NULL, Child;
ULONG_PTR LowVpn, HighVpn, AlignmentVpn;
PFN_NUMBER PageCount;
/* Sanity checks */
ASSERT(BoundaryAddress);
ASSERT(BoundaryAddress <= ((ULONG_PTR)MM_HIGHEST_VAD_ADDRESS));
ASSERT((Alignment & (PAGE_SIZE - 1)) == 0);
/* Calculate page numbers for the length and alignment */
Length = ROUND_TO_PAGES(Length);
PageCount = Length >> PAGE_SHIFT;
AlignmentVpn = Alignment / PAGE_SIZE;
/* Check for kernel mode table (memory areas) */
if (Table->Unused == 1)
{
LowVpn = ALIGN_UP_BY((ULONG_PTR)MmSystemRangeStart >> PAGE_SHIFT, AlignmentVpn);
}
else
{
LowVpn = ALIGN_UP_BY((ULONG_PTR)MM_LOWEST_USER_ADDRESS, Alignment);
}
/* Check if there is enough space below the boundary */
if ((LowVpn + Length) > (BoundaryAddress + 1))
{
return TableFoundNode;
}
/* Check if the table is empty */
if (Table->NumberGenericTableElements == 0)
{
/* Tree is empty, the candidate address is already the best one */
*Base = ALIGN_DOWN_BY(BoundaryAddress + 1 - Length, Alignment);
return TableEmptyTree;
}
/* Calculate the initial upper margin */
HighVpn = (BoundaryAddress + 1) >> PAGE_SHIFT;
/* Starting from the root, follow the right children until we found a node
that ends above the boundary */
Node = RtlRightChildAvl(&Table->BalancedRoot);
while ((Node->EndingVpn < HighVpn) &&
((Child = RtlRightChildAvl(Node)) != NULL)) Node = Child;
/* Now loop the Vad nodes */
while (Node)
{
/* Calculate the lower margin */
LowVpn = ALIGN_UP_BY(Node->EndingVpn + 1, AlignmentVpn);
/* Check if the current bounds are suitable */
if ((HighVpn > LowVpn) && ((HighVpn - LowVpn) >= PageCount))
{
/* There is enough space to add our node */
LowVpn = ALIGN_DOWN_BY(HighVpn - PageCount, AlignmentVpn);
*Base = LowVpn << PAGE_SHIFT;
/* Can we use the current node as parent? */
if (!RtlRightChildAvl(Node))
{
/* Node has no right child, so use it as parent */
*Parent = Node;
return TableInsertAsRight;
}
else
{
/* Node has a right child. This means we must have already
moved one node left from the right-most node we started
with, thus we already have an OldNode! */
ASSERT(OldNode != NULL);
/* The node we had before is the most left grandchild of
that right child, use it as parent. */
ASSERT(RtlLeftChildAvl(OldNode) == NULL);
*Parent = OldNode;
return TableInsertAsLeft;
}
}
/* Update the upper margin if necessary */
if (Node->StartingVpn < HighVpn) HighVpn = Node->StartingVpn;
/* Remember the current node and go to the previous node */
OldNode = Node;
Node = MiGetPreviousNode(Node);
}
/* Check if there's enough space before the lowest Vad */
LowVpn = ALIGN_UP_BY((ULONG_PTR)MI_LOWEST_VAD_ADDRESS, Alignment) / PAGE_SIZE;
if ((HighVpn > LowVpn) && ((HighVpn - LowVpn) >= PageCount))
{
/* There is enough space to add our address */
LowVpn = ALIGN_DOWN_BY(HighVpn - PageCount, Alignment >> PAGE_SHIFT);
*Base = LowVpn << PAGE_SHIFT;
*Parent = OldNode;
return TableInsertAsLeft;
}
/* No address space left at all */
*Base = 0;
*Parent = NULL;
return TableFoundNode;
}
NTSTATUS
NTAPI
MiFindEmptyAddressRangeDownBasedTree(IN SIZE_T Length,
IN ULONG_PTR BoundaryAddress,
IN ULONG_PTR Alignment,
IN PMM_AVL_TABLE Table,
OUT PULONG_PTR Base)
{
PMMADDRESS_NODE Node, LowestNode;
ULONG_PTR LowVpn, BestVpn;
/* Sanity checks */
ASSERT(Table == &MmSectionBasedRoot);
ASSERT(BoundaryAddress);
ASSERT(BoundaryAddress <= ((ULONG_PTR)MM_HIGHEST_VAD_ADDRESS + 1));
/* Compute page length, make sure the boundary address is valid */
Length = ROUND_TO_PAGES(Length);
if ((BoundaryAddress + 1) < Length) return STATUS_NO_MEMORY;
/* Check if the table is empty */
BestVpn = ROUND_DOWN(BoundaryAddress + 1 - Length, Alignment);
if (Table->NumberGenericTableElements == 0)
{
/* Tree is empty, the candidate address is already the best one */
*Base = BestVpn;
return STATUS_SUCCESS;
}
/* Go to the right-most node which should be the biggest address */
Node = Table->BalancedRoot.RightChild;
while (RtlRightChildAvl(Node)) Node = RtlRightChildAvl(Node);
/* Check if we can fit in here */
LowVpn = ROUND_UP(Node->EndingVpn + 1, Alignment);
if ((LowVpn < BoundaryAddress) && (Length <= (BoundaryAddress - LowVpn)))
{
#if (NTDDI_VERSION >= NTDDI_VISTA)
/* Return the address. */
*Base = BestVpn;
#else
/* Note: this is a compatibility hack that mimics a bug in the 2k3
kernel. It will can waste up to Alignment bytes of memory above
the allocation. This bug was fixed in Windows Vista */
*Base = ROUND_DOWN(BoundaryAddress - Length, Alignment);
#endif
return STATUS_SUCCESS;
}
/* Now loop the Vad nodes */
do
{
/* Break out if we've reached the last node */
LowestNode = MiGetPreviousNode(Node);
if (!LowestNode) break;
/* Check if this node could contain the requested address */
LowVpn = ROUND_UP(LowestNode->EndingVpn + 1, Alignment);
if ((LowestNode->EndingVpn < BestVpn) &&
(LowVpn < Node->StartingVpn) &&
(Length <= (Node->StartingVpn - LowVpn)))
{
/* Check if we need to take BoundaryAddress into account */
if (BoundaryAddress < Node->StartingVpn)
{
/* Return the optimal VPN address */
*Base = BestVpn;
return STATUS_SUCCESS;
}
else
{
/* The upper margin is given by the Node's starting address */
*Base = ROUND_DOWN(Node->StartingVpn - Length, Alignment);
return STATUS_SUCCESS;
}
}
/* Move to the next node */
Node = LowestNode;
} while (TRUE);
/* Check if there's enough space before the lowest Vad */
if ((Node->StartingVpn > (ULONG_PTR)MI_LOWEST_VAD_ADDRESS) &&
((Node->StartingVpn - (ULONG_PTR)MI_LOWEST_VAD_ADDRESS) >= Length))
{
/* Check if it fits in perfectly */
if (BoundaryAddress < Node->StartingVpn)
{
/* Return the optimal VPN address */
*Base = BestVpn;
return STATUS_SUCCESS;
}
/* Return an aligned base address within this node */
*Base = ROUND_DOWN(Node->StartingVpn - Length, Alignment);
return STATUS_SUCCESS;
}
/* No address space left at all */
return STATUS_NO_MEMORY;
}
NTSTATUS
NTAPI
MiCheckSecuredVad(IN PMMVAD Vad,
IN PVOID Base,
IN SIZE_T Size,
IN ULONG ProtectionMask)
{
ULONG_PTR StartAddress, EndAddress;
/* Compute start and end address */
StartAddress = (ULONG_PTR)Base;
EndAddress = StartAddress + Size - 1;
/* Are we deleting/unmapping, or changing? */
if (ProtectionMask < MM_DELETE_CHECK)
{
/* Changing... are we allowed to do so? */
if ((Vad->u.VadFlags.NoChange == 1) &&
(Vad->u2.VadFlags2.SecNoChange == 1) &&
(Vad->u.VadFlags.Protection != ProtectionMask))
{
/* Nope, bail out */
DPRINT1("Trying to mess with a no-change VAD!\n");
return STATUS_INVALID_PAGE_PROTECTION;
}
}
else
{
/* This is allowed */
ProtectionMask = 0;
}
/* ARM3 doesn't support this yet */
ASSERT(Vad->u2.VadFlags2.MultipleSecured == 0);
/* Is this a one-secured VAD, like a TEB or PEB? */
if (Vad->u2.VadFlags2.OneSecured)
{
/* Is this allocation being described by the VAD? */
if ((StartAddress <= ((PMMVAD_LONG)Vad)->u3.Secured.EndVpn) &&
(EndAddress >= ((PMMVAD_LONG)Vad)->u3.Secured.StartVpn))
{
/* Guard page? */
if (ProtectionMask & MM_DECOMMIT)
{
DPRINT1("Not allowed to change protection on guard page!\n");
return STATUS_INVALID_PAGE_PROTECTION;
}
/* ARM3 doesn't have read-only VADs yet */
ASSERT(Vad->u2.VadFlags2.ReadOnly == 0);
/* Check if read-write protections are allowed */
if (MmReadWrite[ProtectionMask] < MM_READ_WRITE_ALLOWED)
{
DPRINT1("Invalid protection mask for RW access!\n");
return STATUS_INVALID_PAGE_PROTECTION;
}
}
}
/* All good, allow the change */
return STATUS_SUCCESS;
}
/* EOF */