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Fixes.

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svn path=/trunk/; revision=2259
This commit is contained in:
David Welch 2001-09-25 19:41:38 +00:00
parent 6e4a29babf
commit c0589a9fec
1 changed files with 32 additions and 8 deletions
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40
reactos/ntoskrnl/mm/section.c
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@ -16,7 +16,7 @@
* along with this program; if not, write to the Free Software
* Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/* $Id: section.c,v 1.60 2001/08/26 17:29:09 ekohl Exp $
/* $Id: section.c,v 1.61 2001/09/25 19:41:38 dwelch Exp $
*
* PROJECT: ReactOS kernel
* FILE: ntoskrnl/mm/section.c
@ -157,8 +157,6 @@ MmUnlockSectionSegment(PMM_SECTION_SEGMENT Segment)
KeReleaseMutex(&Segment->Lock, FALSE);
}
VOID
MmSetPageEntrySectionSegment(PMM_SECTION_SEGMENT Segment,
ULONG Offset,
@ -253,6 +251,13 @@ NTSTATUS
MiReadPage(PMEMORY_AREA MemoryArea,
PLARGE_INTEGER Offset,
PVOID* Page)
/*
* FUNCTION: Read a page for a section backed memory area.
* PARAMETERS:
* MemoryArea - Memory area to read the page for.
* Offset - Offset of the page to read.
* Page - Variable that receives a page contains the read data.
*/
{
IO_STATUS_BLOCK IoStatus;
PFILE_OBJECT FileObject;
@ -263,6 +268,11 @@ MiReadPage(PMEMORY_AREA MemoryArea,
FileObject = MemoryArea->Data.SectionData.Section->FileObject;
Fcb = (PREACTOS_COMMON_FCB_HEADER)FileObject->FsContext;
/*
* If the file system is letting us go directly to the cache and the
* memory area was mapped at an offset in the file which is page aligned
* then get the related cache segment.
*/
if (FileObject->Flags & FO_DIRECT_CACHE_PAGING_READ &&
(Offset->QuadPart % PAGESIZE) == 0)
{
@ -272,18 +282,29 @@ MiReadPage(PMEMORY_AREA MemoryArea,
PCACHE_SEGMENT CacheSeg;
LARGE_INTEGER SegOffset;
PHYSICAL_ADDRESS Addr;
/*
* Get the related cache segment; we use a lower level interface than
* filesystems do because it is safe for us to use an offset with a
* alignment less than the file system block size.
*/
Status = CcRosGetCacheSegment(Fcb->Bcb,
(ULONG)Offset->QuadPart,
&BaseOffset,
&BaseAddress,
&UptoDate,
&CacheSeg);
(ULONG)Offset->QuadPart,
&BaseOffset,
&BaseAddress,
&UptoDate,
&CacheSeg);
if (!NT_SUCCESS(Status))
{
return(Status);
}
if (!UptoDate)
{
/*
* If the cache segment isn't up to date then call the file
* system to read in the data.
*/
Mdl = MmCreateMdl(NULL, BaseAddress, Fcb->Bcb->CacheSegmentSize);
MmBuildMdlForNonPagedPool(Mdl);
SegOffset.QuadPart = BaseOffset;
@ -298,6 +319,9 @@ MiReadPage(PMEMORY_AREA MemoryArea,
return(Status);
}
}
/*
* Retrieve the page from the cache segment that we actually want.
*/
Addr = MmGetPhysicalAddress(BaseAddress +
Offset->QuadPart - BaseOffset);
(*Page) = (PVOID)(ULONG)Addr.QuadPart;