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[NTOS]: Add support for user-mode VAD faults on page tables (just a couple lines of extra code).

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[NTOS]: Add support for user-mode VAD demand zero faults.
[NTOS]: Remove broken ASSERT.

svn path=/trunk/; revision=49035
This commit is contained in:
Sir Richard 2010-10-07 17:27:23 +00:00
parent 9dabd64349
commit 12e7ae649b
1 changed files with 45 additions and 17 deletions
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62
reactos/ntoskrnl/mm/ARM3/pagfault.c
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@ -32,8 +32,25 @@ MiCheckVirtualAddress(IN PVOID VirtualAddress,
/* No prototype/section support for now */ /* No prototype/section support for now */
*ProtoVad = NULL; *ProtoVad = NULL;
/* Only valid for user VADs for now */ /* Check if this is a page table address */
ASSERT(VirtualAddress <= MM_HIGHEST_USER_ADDRESS); if (MI_IS_PAGE_TABLE_ADDRESS(VirtualAddress))
{
/* This should never happen, as these addresses are handled by the double-maping */
if (((PMMPTE)VirtualAddress >= MiAddressToPte(MmPagedPoolStart)) &&
((PMMPTE)VirtualAddress <= MmPagedPoolInfo.LastPteForPagedPool))
{
/* Fail such access */
*ProtectCode = MM_NOACCESS;
return NULL;
}
/* Return full access rights */
*ProtectCode = MM_READWRITE;
return NULL;
}
/* Should not be a session address */
ASSERT(MI_IS_SESSION_ADDRESS(VirtualAddress) == FALSE);
/* Special case for shared data */ /* Special case for shared data */
if (PAGE_ALIGN(VirtualAddress) == (PVOID)USER_SHARED_DATA) if (PAGE_ALIGN(VirtualAddress) == (PVOID)USER_SHARED_DATA)
@ -642,7 +659,7 @@ MmArmAccessFault(IN BOOLEAN StoreInstruction,
// //
// Check for kernel fault // Check for kernel fault
// //
if (Address >= MmSystemRangeStart) while (Address >= MmSystemRangeStart)
{ {
// //
// What are you even DOING here? // What are you even DOING here?
@ -718,25 +735,16 @@ MmArmAccessFault(IN BOOLEAN StoreInstruction,
// //
if (MI_IS_PAGE_TABLE_OR_HYPER_ADDRESS(Address)) if (MI_IS_PAGE_TABLE_OR_HYPER_ADDRESS(Address))
{ {
//
// This might happen...not sure yet
//
DPRINT1("FAULT ON PAGE TABLES: %p %lx %lx!\n", Address, *PointerPte, *PointerPde);
#if (_MI_PAGING_LEVELS == 2) #if (_MI_PAGING_LEVELS == 2)
// /* Could be paged pool access from a new process -- synchronize the page directories */
// Map in the page table
//
if (MiCheckPdeForPagedPool(Address) == STATUS_WAIT_1) if (MiCheckPdeForPagedPool(Address) == STATUS_WAIT_1)
{ {
DPRINT1("PAGE TABLES FAULTED IN!\n"); DPRINT1("PAGE TABLES FAULTED IN!\n");
return STATUS_SUCCESS; return STATUS_SUCCESS;
} }
#endif #endif
// /* Otherwise this could be a commit of a virtual address */
// Otherwise the page table doesn't actually exist break;
//
DPRINT1("FAILING\n");
return STATUS_ACCESS_VIOLATION;
} }
/* In this path, we are using the system working set */ /* In this path, we are using the system working set */
@ -866,7 +874,8 @@ MmArmAccessFault(IN BOOLEAN StoreInstruction,
#endif #endif
/* First things first, is the PDE valid? */ /* First things first, is the PDE valid? */
ASSERT(PointerPde != MiAddressToPde(PTE_BASE)); // DPRINT1("The PDE we faulted on: %lx %lx\n", PointerPde, MiAddressToPde(PTE_BASE));
//ASSERT(PointerPde != MiAddressToPde(PTE_BASE));
ASSERT(PointerPde->u.Hard.LargePage == 0); ASSERT(PointerPde->u.Hard.LargePage == 0);
if (PointerPde->u.Hard.Valid == 0) if (PointerPde->u.Hard.Valid == 0)
{ {
@ -901,8 +910,27 @@ MmArmAccessFault(IN BOOLEAN StoreInstruction,
ASSERT(PointerPde->u.Hard.Valid == 1); ASSERT(PointerPde->u.Hard.Valid == 1);
} }
/* Now capture the PTE. We only handle cases where it's totally empty */ /* Now capture the PTE. Ignore virtual faults for now */
TempPte = *PointerPte; TempPte = *PointerPte;
ASSERT(TempPte.u.Hard.Valid == 0);
/* Quick check for demand-zero */
if (TempPte.u.Long == (MM_READWRITE << MM_PTE_SOFTWARE_PROTECTION_BITS))
{
/* Resolve the fault */
//DPRINT1("VAD demand-zero fault: %p\n", Address);
MiResolveDemandZeroFault(Address,
PointerPte,
CurrentProcess,
MM_NOIRQL);
/* Return the status */
MiUnlockProcessWorkingSet(CurrentProcess, CurrentThread);
return STATUS_PAGE_FAULT_DEMAND_ZERO;
}
/* Don't handle prototype PTEs yet -- only kernel demand zero PTEs */
ASSERT(TempPte.u.Soft.Prototype == 0);
ASSERT(TempPte.u.Long == 0); ASSERT(TempPte.u.Long == 0);
/* Check if this address range belongs to a valid allocation (VAD) */ /* Check if this address range belongs to a valid allocation (VAD) */