sys: initial ProcessBuffer implementation

This commit is contained in:
Bill Zissimopoulos
2017-02-23 16:06:55 -08:00
parent 441c45c77f
commit 4b43cc590f
10 changed files with 694 additions and 139 deletions

View File

@ -44,6 +44,7 @@ enum
{
/* ReadNonCached */
RequestIrp = 0,
RequestCookie = 1,
RequestSafeMdl = 1,
RequestAddress = 2,
RequestProcess = 3,
@ -346,41 +347,71 @@ NTSTATUS FspFsvolReadPrepare(
{
PAGED_CODE();
NTSTATUS Result;
FSP_SAFE_MDL *SafeMdl = 0;
PVOID Address;
PEPROCESS Process;
/* create a "safe" MDL if necessary */
if (!FspSafeMdlCheck(Irp->MdlAddress))
if (FspFsvolDeviceReadShouldUseProcessBuffer(
IoGetCurrentIrpStackLocation(Irp)->DeviceObject, Request->Req.Read.Length))
{
Result = FspSafeMdlCreate(Irp->MdlAddress, IoWriteAccess, &SafeMdl);
NTSTATUS Result;
PVOID Cookie;
PVOID Address;
PEPROCESS Process;
if (0 == MmGetSystemAddressForMdlSafe(Irp->MdlAddress, NormalPagePriority))
return STATUS_INSUFFICIENT_RESOURCES; /* something is seriously screwy! */
Result = FspProcessBufferAcquire(Request->Req.Read.Length, &Cookie, &Address);
if (!NT_SUCCESS(Result))
return Result;
}
/* map the MDL into user-mode */
Result = FspMapLockedPagesInUserMode(
0 != SafeMdl ? SafeMdl->Mdl : Irp->MdlAddress, &Address, 0);
if (!NT_SUCCESS(Result))
/* get a pointer to the current process so that we can release the buffer later */
Process = PsGetCurrentProcess();
ObReferenceObject(Process);
Request->Req.Read.Address = (UINT64)(UINT_PTR)Address;
FspIopRequestContext(Request, RequestCookie) = Cookie;
FspIopRequestContext(Request, RequestAddress) = Address;
FspIopRequestContext(Request, RequestProcess) = Process;
return STATUS_SUCCESS;
}
else
{
if (0 != SafeMdl)
FspSafeMdlDelete(SafeMdl);
NTSTATUS Result;
FSP_SAFE_MDL *SafeMdl = 0;
PVOID Address;
PEPROCESS Process;
return Result;
/* create a "safe" MDL if necessary */
if (!FspSafeMdlCheck(Irp->MdlAddress))
{
Result = FspSafeMdlCreate(Irp->MdlAddress, IoWriteAccess, &SafeMdl);
if (!NT_SUCCESS(Result))
return Result;
}
/* map the MDL into user-mode */
Result = FspMapLockedPagesInUserMode(
0 != SafeMdl ? SafeMdl->Mdl : Irp->MdlAddress, &Address, 0);
if (!NT_SUCCESS(Result))
{
if (0 != SafeMdl)
FspSafeMdlDelete(SafeMdl);
return Result;
}
/* get a pointer to the current process so that we can unmap the address later */
Process = PsGetCurrentProcess();
ObReferenceObject(Process);
Request->Req.Read.Address = (UINT64)(UINT_PTR)Address;
FspIopRequestContext(Request, RequestSafeMdl) = SafeMdl;
FspIopRequestContext(Request, RequestAddress) = Address;
FspIopRequestContext(Request, RequestProcess) = Process;
return STATUS_SUCCESS;
}
/* get a pointer to the current process so that we can unmap the address later */
Process = PsGetCurrentProcess();
ObReferenceObject(Process);
Request->Req.Read.Address = (UINT64)(UINT_PTR)Address;
FspIopRequestContext(Request, RequestSafeMdl) = SafeMdl;
FspIopRequestContext(Request, RequestAddress) = Address;
FspIopRequestContext(Request, RequestProcess) = Process;
return STATUS_SUCCESS;
}
NTSTATUS FspFsvolReadComplete(
@ -400,15 +431,37 @@ NTSTATUS FspFsvolReadComplete(
if (Response->IoStatus.Information > Request->Req.Read.Length)
FSP_RETURN(Result = STATUS_INTERNAL_ERROR);
FSP_SAFE_MDL *SafeMdl = FspIopRequestContext(Request, RequestSafeMdl);
if (FspFsvolDeviceReadShouldUseProcessBuffer(
IrpSp->DeviceObject, Request->Req.Read.Length))
{
PVOID Address = FspIopRequestContext(Request, RequestAddress);
PVOID SystemAddress = MmGetSystemAddressForMdlSafe(Irp->MdlAddress, NormalPagePriority);
ASSERT(0 != Address);
try
{
RtlCopyMemory(SystemAddress, Address, Response->IoStatus.Information);
}
except (EXCEPTION_EXECUTE_HANDLER)
{
Result = GetExceptionCode();
Result = FsRtlIsNtstatusExpected(Result) ? STATUS_INVALID_USER_BUFFER : Result;
FSP_RETURN();
}
}
else
{
FSP_SAFE_MDL *SafeMdl = FspIopRequestContext(Request, RequestSafeMdl);
if (0 != SafeMdl)
FspSafeMdlCopyBack(SafeMdl);
}
PFILE_OBJECT FileObject = IrpSp->FileObject;
LARGE_INTEGER ReadOffset = IrpSp->Parameters.Read.ByteOffset;
BOOLEAN PagingIo = BooleanFlagOn(Irp->Flags, IRP_PAGING_IO);
BOOLEAN SynchronousIo = BooleanFlagOn(FileObject->Flags, FO_SYNCHRONOUS_IO);
if (0 != SafeMdl)
FspSafeMdlCopyBack(SafeMdl);
/* if we are top-level */
if (0 == FspIrpTopFlags(Irp))
{
@ -442,29 +495,57 @@ static VOID FspFsvolReadNonCachedRequestFini(FSP_FSCTL_TRANSACT_REQ *Request, PV
PAGED_CODE();
PIRP Irp = Context[RequestIrp];
FSP_SAFE_MDL *SafeMdl = Context[RequestSafeMdl];
PVOID Address = Context[RequestAddress];
PEPROCESS Process = Context[RequestProcess];
if (0 != Address)
if (0 != Irp && FspFsvolDeviceReadShouldUseProcessBuffer(
IoGetCurrentIrpStackLocation(Irp)->DeviceObject, Request->Req.Read.Length))
{
KAPC_STATE ApcState;
BOOLEAN Attach;
PVOID Cookie = Context[RequestCookie];
PVOID Address = Context[RequestAddress];
PEPROCESS Process = Context[RequestProcess];
ASSERT(0 != Process);
Attach = Process != PsGetCurrentProcess();
if (0 != Address)
{
KAPC_STATE ApcState;
BOOLEAN Attach;
if (Attach)
KeStackAttachProcess(Process, &ApcState);
MmUnmapLockedPages(Address, 0 != SafeMdl ? SafeMdl->Mdl : Irp->MdlAddress);
if (Attach)
KeUnstackDetachProcess(&ApcState);
ASSERT(0 != Process);
Attach = Process != PsGetCurrentProcess();
ObDereferenceObject(Process);
if (Attach)
KeStackAttachProcess(Process, &ApcState);
FspProcessBufferRelease(Cookie, Address);
if (Attach)
KeUnstackDetachProcess(&ApcState);
ObDereferenceObject(Process);
}
}
else
{
FSP_SAFE_MDL *SafeMdl = Context[RequestSafeMdl];
PVOID Address = Context[RequestAddress];
PEPROCESS Process = Context[RequestProcess];
if (0 != SafeMdl)
FspSafeMdlDelete(SafeMdl);
if (0 != Address)
{
KAPC_STATE ApcState;
BOOLEAN Attach;
ASSERT(0 != Process);
Attach = Process != PsGetCurrentProcess();
if (Attach)
KeStackAttachProcess(Process, &ApcState);
MmUnmapLockedPages(Address, 0 != SafeMdl ? SafeMdl->Mdl : Irp->MdlAddress);
if (Attach)
KeUnstackDetachProcess(&ApcState);
ObDereferenceObject(Process);
}
if (0 != SafeMdl)
FspSafeMdlDelete(SafeMdl);
}
if (0 != Irp)
{