[reactos] 44/100: [NTOS:CC] Acquire file for flush when flushing if necessary

[Jérôme Gardou]

https://git.reactos.org/?p=reactos.git;a=commitdiff;h=f8aa14ce4e651ca57f119…

commit f8aa14ce4e651ca57f11904b482972fb0f749295
Author:     Jérôme Gardou <jerome.gardou(a)reactos.org>
AuthorDate: Fri Dec 4 10:18:32 2020 +0100
Commit:     Jérôme Gardou <jerome.gardou(a)reactos.org>
CommitDate: Wed Feb 3 09:41:22 2021 +0100

    [NTOS:CC] Acquire file for flush when flushing if necessary
---
 ntoskrnl/cc/view.c                | 16 ++++++++++++++++
 ntoskrnl/include/internal/fsrtl.h |  8 ++++++++
 2 files changed, 24 insertions(+)

diff --git a/ntoskrnl/cc/view.c b/ntoskrnl/cc/view.c
index de4a75ea8f7..ee0ec497d40 100644
--- a/ntoskrnl/cc/view.c
+++ b/ntoskrnl/cc/view.c
@@ -172,11 +172,27 @@ CcRosFlushVacb (
     SIZE_T FlushSize = min(VACB_MAPPING_GRANULARITY,
         Vacb->SharedCacheMap->SectionSize.QuadPart -
Vacb->FileOffset.QuadPart);
     NTSTATUS Status;
+    BOOLEAN HaveLock = FALSE;
 
     CcRosUnmarkDirtyVacb(Vacb, TRUE);
 
+    /* Lock for flush, if we are not already the top-level */
+    if (IoGetTopLevelIrp() != (PIRP)FSRTL_CACHE_TOP_LEVEL_IRP)
+    {
+        Status = FsRtlAcquireFileForCcFlushEx(Vacb->SharedCacheMap->FileObject);
+        if (!NT_SUCCESS(Status))
+            goto quit;
+        HaveLock = TRUE;
+    }
+
     Status = MmFlushVirtualMemory(NULL, &Vacb->BaseAddress, &FlushSize,
&Iosb);
 
+    if (HaveLock)
+    {
+        FsRtlReleaseFileForCcFlush(Vacb->SharedCacheMap->FileObject);
+    }
+
+quit:
     if (!NT_SUCCESS(Status))
         CcRosMarkDirtyVacb(Vacb);
 
diff --git a/ntoskrnl/include/internal/fsrtl.h b/ntoskrnl/include/internal/fsrtl.h
index 79cc3b6cfbc..228bb7a1cf8 100644
--- a/ntoskrnl/include/internal/fsrtl.h
+++ b/ntoskrnl/include/internal/fsrtl.h
@@ -148,3 +148,11 @@ NTSTATUS
 NTAPI
 FsRtlAcquireToCreateMappedSection(_In_ PFILE_OBJECT FileObject,
                                   _In_ ULONG SectionPageProtection);
+
+VOID
+NTAPI
+FsRtlReleaseFileForCcFlush(IN PFILE_OBJECT FileObject);
+
+NTSTATUS
+NTAPI
+FsRtlAcquireFileForCcFlushEx(IN PFILE_OBJECT FileObject);