* PURPOSE: Large Mapped Control Block (MCB) support for File System Drivers
* PROGRAMMERS: Aleksey Bragin <aleksey@reactos.org>
* Jan Kratochvil <project-captive@jankratochvil.net>
+ * Trevor Thompson
*/
/* INCLUDES ******************************************************************/
PLARGE_MCB_MAPPING Mapping;
} BASE_MCB_INTERNAL, *PBASE_MCB_INTERNAL;
+/*
static LARGE_MCB_MAPPING_ENTRY StaticRunBelow0 = {
- {{-1}}, /* ignored */
+ {{-1}}, // ignored
{{0}},
- {{-1}}, /* ignored */
+ {{-1}}, // ignored
};
+*/
static PVOID NTAPI McbMappingAllocate(PRTL_GENERIC_TABLE Table, CLONG Bytes)
{
IN LONGLONG SectorCount)
{
BOOLEAN Result = TRUE;
+ BOOLEAN IntResult;
PBASE_MCB_INTERNAL Mcb = (PBASE_MCB_INTERNAL)OpaqueMcb;
LARGE_MCB_MAPPING_ENTRY Node, NeedleRun;
PLARGE_MCB_MAPPING_ENTRY LowerRun, HigherRun;
BOOLEAN NewElement;
+ LONGLONG IntLbn;
DPRINT("FsRtlAddBaseMcbEntry(%p, %I64d, %I64d, %I64d)\n", OpaqueMcb, Vbn, Lbn, SectorCount);
goto quit;
}
+ IntResult = FsRtlLookupBaseMcbEntry(OpaqueMcb, Vbn, &IntLbn, NULL, NULL, NULL, NULL);
+ if (IntResult)
+ {
+ if (IntLbn != -1 && IntLbn != Lbn)
+ {
+ Result = FALSE;
+ goto quit;
+ }
+ }
+
/* clean any possible previous entries in our range */
FsRtlRemoveBaseMcbEntry(OpaqueMcb, Vbn, SectorCount);
NeedleRun.StartingLbn.QuadPart = ~0ULL;
Mcb->Mapping->Table.CompareRoutine = McbMappingIntersectCompare;
if ((LowerRun = RtlLookupElementGenericTable(&Mcb->Mapping->Table, &NeedleRun)) &&
- (LowerRun->StartingLbn.QuadPart < Node.StartingLbn.QuadPart))
+ (LowerRun->StartingLbn.QuadPart + (LowerRun->RunEndVbn.QuadPart - LowerRun->RunStartVbn.QuadPart) == Node.StartingLbn.QuadPart))
{
ASSERT(LowerRun->RunEndVbn.QuadPart == Node.RunStartVbn.QuadPart);
Node.RunStartVbn.QuadPart = LowerRun->RunStartVbn.QuadPart;
Node.StartingLbn.QuadPart = LowerRun->StartingLbn.QuadPart;
Mcb->Mapping->Table.CompareRoutine = McbMappingCompare;
RtlDeleteElementGenericTable(&Mcb->Mapping->Table, LowerRun);
+ --Mcb->PairCount;
DPRINT("Intersecting lower run found (%I64d,%I64d) Lbn: %I64d\n", LowerRun->RunStartVbn.QuadPart, LowerRun->RunEndVbn.QuadPart, LowerRun->StartingLbn.QuadPart);
}
Node.RunEndVbn.QuadPart = HigherRun->RunEndVbn.QuadPart;
Mcb->Mapping->Table.CompareRoutine = McbMappingCompare;
RtlDeleteElementGenericTable(&Mcb->Mapping->Table, HigherRun);
+ --Mcb->PairCount;
DPRINT("Intersecting higher run found (%I64d,%I64d) Lbn: %I64d\n", HigherRun->RunStartVbn.QuadPart, HigherRun->RunEndVbn.QuadPart, HigherRun->StartingLbn.QuadPart);
}
Mcb->Mapping->Table.CompareRoutine = McbMappingCompare;
/* finally insert the resulting run */
RtlInsertElementGenericTable(&Mcb->Mapping->Table, &Node, sizeof(Node), &NewElement);
+ ++Mcb->PairCount;
ASSERT(NewElement);
// NB: Two consecutive runs can only be merged, if actual LBNs also match!
BOOLEAN
NTAPI
FsRtlGetNextBaseMcbEntry(IN PBASE_MCB OpaqueMcb,
- IN ULONG RunIndex,
- OUT PLONGLONG Vbn,
- OUT PLONGLONG Lbn,
- OUT PLONGLONG SectorCount)
+ IN ULONG RunIndex,
+ OUT PLONGLONG Vbn,
+ OUT PLONGLONG Lbn,
+ OUT PLONGLONG SectorCount)
{
BOOLEAN Result = FALSE;
PBASE_MCB_INTERNAL Mcb = (PBASE_MCB_INTERNAL)OpaqueMcb;
- ULONG RunIndexRemaining;
- PLARGE_MCB_MAPPING_ENTRY Run, RunFound = NULL, RunFoundLower = NULL, RunFoundHigher = NULL;
- BOOLEAN First = TRUE;
-
- DPRINT("FsRtlGetNextBaseMcbEntry(%p, %d, %p, %p, %p)\n", OpaqueMcb, RunIndex, Vbn, Lbn, SectorCount);
+ PLARGE_MCB_MAPPING_ENTRY Run = NULL;
+ ULONG CurrentIndex = 0;
+ ULONGLONG LastVbn = 0;
+ ULONGLONG LastSectorCount = 0;
- RunIndexRemaining = RunIndex;
-
- /* Traverse the tree */
+ // Traverse the tree
for (Run = (PLARGE_MCB_MAPPING_ENTRY)RtlEnumerateGenericTable(&Mcb->Mapping->Table, TRUE);
- Run;
+ Run;
Run = (PLARGE_MCB_MAPPING_ENTRY)RtlEnumerateGenericTable(&Mcb->Mapping->Table, FALSE))
{
- if (First)
+ // is the current index a hole?
+ if (Run->RunStartVbn.QuadPart > (LastVbn + LastSectorCount))
{
- /* Take care when we must emulate missing 'hole' run at start of our run list. */
- if (Run->RunStartVbn.QuadPart > 0)
+ // Is this the index we're looking for?
+ if (RunIndex == CurrentIndex)
{
- if (RunIndexRemaining == 0)
- {
- RunFoundLower = &StaticRunBelow0;
- RunFoundHigher = Run;
-
- /* stop the traversal */
- break;
- }
- /* If someone wants RunIndex #1 we are already on it. */
- RunIndexRemaining--;
+ *Vbn = LastVbn + LastSectorCount;
+ *Lbn = -1;
+ *SectorCount = Run->RunStartVbn.QuadPart - *Vbn;
+
+ Result = TRUE;
+ goto quit;
}
- First = FALSE;
- }
- if (RunIndexRemaining > 0)
- {
- /* FIXME: performance: non-linear direct seek to the requested RunIndex */
- RunIndexRemaining--;
- if (RunIndexRemaining == 0)
- RunFoundLower = Run;
- else
- RunIndexRemaining--;
-
- /* continue the traversal */
- continue;
+ CurrentIndex++;
}
- if (RunFoundLower)
- RunFoundHigher = Run;
- else
- RunFound = Run;
-
- /* stop the traversal */
- break;
- }
-
- if (RunFound) DPRINT("RunFound(%lu %lu %lu)\n", RunFound->RunStartVbn.LowPart, RunFound->RunEndVbn.LowPart, RunFound->StartingLbn.LowPart);
- if (RunFoundLower) DPRINT("RunFoundLower(%lu %lu %lu)\n", RunFoundLower->RunStartVbn.LowPart, RunFoundLower->RunEndVbn.LowPart, RunFoundLower->StartingLbn.LowPart);
- if (RunFoundHigher) DPRINT("RunFoundHigher(%lu %lu %lu)\n", RunFoundHigher->RunStartVbn.LowPart, RunFoundHigher->RunEndVbn.LowPart, RunFoundHigher->StartingLbn.LowPart);
-
- if (RunFound)
- {
- ASSERT(RunFoundLower == NULL);
- ASSERT(RunFoundHigher == NULL);
+ if (RunIndex == CurrentIndex)
+ {
+ *Vbn = Run->RunStartVbn.QuadPart;
+ *Lbn = Run->StartingLbn.QuadPart;
+ *SectorCount = Run->RunEndVbn.QuadPart - Run->RunStartVbn.QuadPart;
- if (Vbn)
- *Vbn = RunFound->RunStartVbn.QuadPart;
- if (Lbn)
- *Lbn = RunFound->StartingLbn.QuadPart;
- if (SectorCount)
- *SectorCount = RunFound->RunEndVbn.QuadPart - RunFound->RunStartVbn.QuadPart;
+ Result = TRUE;
+ goto quit;
+ }
- Result = TRUE;
- goto quit;
+ CurrentIndex++;
+ LastVbn = Run->RunStartVbn.QuadPart;
+ LastSectorCount = Run->RunEndVbn.QuadPart - Run->RunStartVbn.QuadPart;
}
- if (RunFoundLower && RunFoundHigher)
- {
- //ASSERT(RunFoundHigher != NULL);
-
- if (Vbn)
- *Vbn = RunFoundLower->RunEndVbn.QuadPart;
- if (Lbn)
- *Lbn = -1;
- if (SectorCount)
- *SectorCount = RunFoundHigher->RunStartVbn.QuadPart - RunFoundLower->RunEndVbn.QuadPart;
-
- Result = TRUE;
- goto quit;
- }
-
- ASSERT(RunFoundHigher == NULL);
+ // these values are meaningless when returning false (but setting them can be helpful for debugging purposes)
+ *Vbn = 0xdeadbeef;
+ *Lbn = 0xdeadbeef;
+ *SectorCount = 0xdeadbeef;
quit:
DPRINT("FsRtlGetNextBaseMcbEntry(%p, %d, %p, %p, %p) = %d (%I64d, %I64d, %I64d)\n", Mcb, RunIndex, Vbn, Lbn, SectorCount, Result, *Vbn, *Lbn, *SectorCount);
}
/*
- * @unimplemented
+ * @implemented
*/
BOOLEAN
NTAPI
FsRtlLookupBaseMcbEntry(IN PBASE_MCB OpaqueMcb,
- IN LONGLONG Vbn,
- OUT PLONGLONG Lbn OPTIONAL,
- OUT PLONGLONG SectorCountFromLbn OPTIONAL,
- OUT PLONGLONG StartingLbn OPTIONAL,
- OUT PLONGLONG SectorCountFromStartingLbn OPTIONAL,
- OUT PULONG Index OPTIONAL)
+ IN LONGLONG Vbn,
+ OUT PLONGLONG Lbn OPTIONAL,
+ OUT PLONGLONG SectorCountFromLbn OPTIONAL,
+ OUT PLONGLONG StartingLbn OPTIONAL,
+ OUT PLONGLONG SectorCountFromStartingLbn OPTIONAL,
+ OUT PULONG Index OPTIONAL)
{
BOOLEAN Result = FALSE;
- PBASE_MCB_INTERNAL Mcb = (PBASE_MCB_INTERNAL)OpaqueMcb;
-
- ULONG RunIndex = 0;
- PLARGE_MCB_MAPPING_ENTRY Run, RunFound = NULL, RunFoundLower = NULL, RunFoundHigher = NULL;
- BOOLEAN First = TRUE;
+ ULONG i;
+ LONGLONG LastVbn = 0, LastLbn = 0, Count = 0; // the last values we've found during traversal
DPRINT("FsRtlLookupBaseMcbEntry(%p, %I64d, %p, %p, %p, %p, %p)\n", OpaqueMcb, Vbn, Lbn, SectorCountFromLbn, StartingLbn, SectorCountFromStartingLbn, Index);
- /* Traverse the tree */
- for (Run = (PLARGE_MCB_MAPPING_ENTRY)RtlEnumerateGenericTable(&Mcb->Mapping->Table, TRUE);
- Run;
- Run = (PLARGE_MCB_MAPPING_ENTRY)RtlEnumerateGenericTable(&Mcb->Mapping->Table, FALSE))
+ for (i = 0; FsRtlGetNextBaseMcbEntry(OpaqueMcb, i, &LastVbn, &LastLbn, &Count); i++)
{
- if (First)
- {
- /* Take care when we must emulate missing 'hole' run at start of our run list. */
- if (Run->RunStartVbn.QuadPart > 0)
- {
- RunIndex++;
- RunFoundLower = &StaticRunBelow0;
- }
- First = FALSE;
- }
-
- if (Run->RunStartVbn.QuadPart <= Vbn && Vbn < Run->RunEndVbn.QuadPart)
- {
- RunFound = Run;
- RunFoundLower = NULL;
- /* stop the traversal; hit */
- break;
- }
-
- if (Run->RunEndVbn.QuadPart <= Vbn)
+ // have we reached the target mapping?
+ if (Vbn < LastVbn + Count)
{
- RunFoundLower = Run;
- if (Run->StartingLbn.QuadPart > 0)
+ if (Lbn)
{
- RunIndex += 2;
+ if (LastLbn == -1)
+ *Lbn = -1;
+ else
+ *Lbn = LastLbn + (Vbn - LastVbn);
}
- /* continue the traversal; not yet crossed by the run */
- continue;
- }
- if (Vbn < Run->RunStartVbn.QuadPart)
- {
- RunFoundHigher = Run;
- RunIndex++;
- /* stop the traversal; the run skipped us */
- break;
+ if (SectorCountFromLbn)
+ *SectorCountFromLbn = LastVbn + Count - Vbn;
+ if (StartingLbn)
+ *StartingLbn = LastLbn;
+ if (SectorCountFromStartingLbn)
+ *SectorCountFromStartingLbn = LastVbn + Count - LastVbn;
+ if (Index)
+ *Index = i;
+
+ Result = TRUE;
+ goto quit;
}
-
- ASSERT(FALSE);
- /* stop the traversal */
- break;
}
- if (RunFound)
- {
- ASSERT(RunFoundLower == NULL);
- ASSERT(RunFoundHigher == NULL);
-
- if (Lbn)
- *Lbn = RunFound->StartingLbn.QuadPart + (Vbn - RunFound->RunStartVbn.QuadPart);
-
- if (SectorCountFromLbn) /* FIXME: 'after' means including current 'Lbn' or without it? */
- *SectorCountFromLbn = RunFound->RunEndVbn.QuadPart - Vbn;
- if (StartingLbn)
- *StartingLbn = RunFound->StartingLbn.QuadPart;
- if (SectorCountFromStartingLbn)
- *SectorCountFromStartingLbn = RunFound->RunEndVbn.QuadPart - RunFound->RunStartVbn.QuadPart;
- if (Index)
- *Index = RunIndex;
-
- Result = TRUE;
- goto quit;
- }
-
- if (RunFoundHigher)
- {
- /* search for hole */
- ASSERT(RunFoundLower != NULL);
-
- if (Lbn)
- *Lbn = ~0ull;
- if (SectorCountFromLbn) /* FIXME: 'after' means including current 'Lbn' or without it? */
- *SectorCountFromLbn = RunFoundHigher->RunStartVbn.QuadPart - Vbn;
- if (StartingLbn)
- *StartingLbn = ~0ull;
- if (SectorCountFromStartingLbn)
- *SectorCountFromStartingLbn = RunFoundHigher->RunStartVbn.QuadPart - RunFoundLower->RunEndVbn.QuadPart;
- if (Index)
- *Index = RunIndex - 2;
-
- Result = TRUE;
- goto quit;
- }
-
- /* We may have some 'RunFoundLower'. */
+ if (Lbn)
+ *Lbn = -1;
+ if (StartingLbn)
+ *StartingLbn = -1;
quit:
DPRINT("FsRtlLookupBaseMcbEntry(%p, %I64d, %p, %p, %p, %p, %p) = %d (%I64d, %I64d, %I64d, %I64d, %d)\n",
NTAPI
FsRtlNumberOfRunsInBaseMcb(IN PBASE_MCB OpaqueMcb)
{
- PBASE_MCB_INTERNAL Mcb = (PBASE_MCB_INTERNAL)OpaqueMcb;
- LONGLONG LbnAtVbn0 = -1;
- ULONG Nodes = RtlNumberGenericTableElements(&Mcb->Mapping->Table);
ULONG NumberOfRuns = 0;
+ LONGLONG Vbn, Lbn, Count;
+ int i;
DPRINT("FsRtlNumberOfRunsInBaseMcb(%p)\n", OpaqueMcb);
- if (Nodes == 0) goto quit;
-
- FsRtlLookupBaseMcbEntry(OpaqueMcb,
- 0, /* Vbn */
- &LbnAtVbn0, /* Lbn */
- NULL, NULL, NULL, NULL); /* 4 output arguments - not interested in them */
-
-
- /* Return the count */
- //return Mcb->PairCount;
- /* Return the number of 'real' and 'hole' runs.
- * If we do not have sector 0 as 'real' emulate a 'hole' there.
- */
- NumberOfRuns = Nodes * 2 - (LbnAtVbn0 != -1 ? 1 : 0); /* include holes as runs */
+ // Count how many Mcb entries there are
+ for (i = 0; FsRtlGetNextBaseMcbEntry(OpaqueMcb, i, &Vbn, &Lbn, &Count); i++)
+ {
+ NumberOfRuns++;
+ }
-quit:
DPRINT("FsRtlNumberOfRunsInBaseMcb(%p) = %d\n", OpaqueMcb, NumberOfRuns);
return NumberOfRuns;
}
//ASSERT(NeedleRun.RunEndVbn.QuadPart <= HaystackRun->RunEndVbn.QuadPart);
Mcb->Mapping->Table.CompareRoutine = McbMappingCompare;
RtlDeleteElementGenericTable(&Mcb->Mapping->Table, HaystackRun);
+ --Mcb->PairCount;
Mcb->Mapping->Table.CompareRoutine = McbMappingIntersectCompare;
}
}
}
if (InsertLowerRun)
+ {
ExistingRun = RtlInsertElementGenericTable(&Mcb->Mapping->Table, InsertLowerRun, sizeof(*InsertLowerRun), &NewElement);
+ ++Mcb->PairCount;
+ }
ASSERT(ExistingRun == NULL);
projects / reactos.git / blobdiff