After much delay and anticipation, welcome RAIDFrame into the FreeBSD

world.  This should be considered highly experimental.

Approved-by:	re

1 files changed, 217 insertions, 0 deletions

diff --git a/sys/dev/raidframe/rf_pqdeg.c b/sys/dev/raidframe/rf_pqdeg.c
new file mode 100644
index 0000000..e76ccdf
--- /dev/null
+++ b/sys/dev/raidframe/rf_pqdeg.c
@@ -0,0 +1,217 @@
+/*	$FreeBSD$ */
+/*	$NetBSD: rf_pqdeg.c,v 1.5 2000/01/07 03:41:04 oster Exp $	*/
+/*
+ * Copyright (c) 1995 Carnegie-Mellon University.
+ * All rights reserved.
+ *
+ * Author: Daniel Stodolsky
+ *
+ * Permission to use, copy, modify and distribute this software and
+ * its documentation is hereby granted, provided that both the copyright
+ * notice and this permission notice appear in all copies of the
+ * software, derivative works or modified versions, and any portions
+ * thereof, and that both notices appear in supporting documentation.
+ *
+ * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
+ * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
+ * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
+ *
+ * Carnegie Mellon requests users of this software to return to
+ *
+ *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
+ *  School of Computer Science
+ *  Carnegie Mellon University
+ *  Pittsburgh PA 15213-3890
+ *
+ * any improvements or extensions that they make and grant Carnegie the
+ * rights to redistribute these changes.
+ */
+
+#include <dev/raidframe/rf_archs.h>
+
+#if (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0)
+
+#include <dev/raidframe/rf_types.h>
+#include <dev/raidframe/rf_raid.h>
+#include <dev/raidframe/rf_dag.h>
+#include <dev/raidframe/rf_dagutils.h>
+#include <dev/raidframe/rf_dagfuncs.h>
+#include <dev/raidframe/rf_dagffrd.h>
+#include <dev/raidframe/rf_dagffwr.h>
+#include <dev/raidframe/rf_dagdegrd.h>
+#include <dev/raidframe/rf_dagdegwr.h>
+#include <dev/raidframe/rf_etimer.h>
+#include <dev/raidframe/rf_pqdeg.h>
+#include <dev/raidframe/rf_general.h>
+#include <dev/raidframe/rf_pqdegdags.h>
+#include <dev/raidframe/rf_pq.h>
+
+/*
+   Degraded mode dag functions for P+Q calculations.
+
+   The following nomenclature is used.
+
+   PQ_<D><P><Q>_Create{Large,Small}<Write|Read>DAG
+
+   where <D><P><Q> are single digits representing the number of failed
+   data units <D> (0,1,2), parity units <P> (0,1), and Q units <Q>, effecting
+   the I/O. The reads have only  PQ_<D><P><Q>_CreateReadDAG variants, while
+   the single fault writes have both large and small write versions. (Single fault
+   PQ is equivalent to normal mode raid 5 in many aspects.
+
+   Some versions degenerate into the same case, and are grouped together below.
+*/
+
+/* Reads, single failure
+
+   we have parity, so we can do a raid 5
+   reconstruct read.
+*/
+
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_100_CreateReadDAG)
+{
+	rf_CreateDegradedReadDAG(raidPtr, asmap, dag_h, bp, flags, allocList, &rf_pRecoveryFuncs);
+}
+/* Reads double failure  */
+
+/*
+   Q is lost, but not parity
+   so we can a raid 5 reconstruct read.
+*/
+
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_101_CreateReadDAG)
+{
+	rf_CreateDegradedReadDAG(raidPtr, asmap, dag_h, bp, flags, allocList, &rf_pRecoveryFuncs);
+}
+/*
+  parity is lost, so we need to
+  do a reconstruct read and recompute
+  the data with Q.
+*/
+
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_110_CreateReadDAG)
+{
+	RF_PhysDiskAddr_t *temp;
+	/* swap P and Q pointers to fake out the DegradedReadDAG code */
+	temp = asmap->parityInfo;
+	asmap->parityInfo = asmap->qInfo;
+	asmap->qInfo = temp;
+	rf_CreateDegradedReadDAG(raidPtr, asmap, dag_h, bp, flags, allocList, &rf_qRecoveryFuncs);
+}
+/*
+  Two data units are dead in this stripe, so we will need read
+  both P and Q to reconstruct the data. Note that only
+  one data unit we are reading may actually be missing.
+*/
+RF_CREATE_DAG_FUNC_DECL(rf_CreateDoubleDegradedReadDAG);
+RF_CREATE_DAG_FUNC_DECL(rf_CreateDoubleDegradedReadDAG)
+{
+	rf_PQ_DoubleDegRead(raidPtr, asmap, dag_h, bp, flags, allocList);
+}
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_200_CreateReadDAG);
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_200_CreateReadDAG)
+{
+	rf_CreateDoubleDegradedReadDAG(raidPtr, asmap, dag_h, bp, flags, allocList);
+}
+/* Writes, single failure */
+
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_100_CreateWriteDAG);
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_100_CreateWriteDAG)
+{
+	if (asmap->numStripeUnitsAccessed != 1 &&
+	    asmap->failedPDAs[0]->numSector != 
+	    raidPtr->Layout.sectorsPerStripeUnit)
+		RF_PANIC();
+	rf_CommonCreateSimpleDegradedWriteDAG(raidPtr, asmap, dag_h, bp, 
+		      flags, allocList, 2, 
+		      (int (*) (RF_DagNode_t *)) rf_Degraded_100_PQFunc, 
+		      RF_FALSE);
+}
+/* Dead  P - act like a RAID 5 small write with parity = Q */
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_010_CreateSmallWriteDAG)
+{
+	RF_PhysDiskAddr_t *temp;
+	/* swap P and Q pointers to fake out the DegradedReadDAG code */
+	temp = asmap->parityInfo;
+	asmap->parityInfo = asmap->qInfo;
+	asmap->qInfo = temp;
+	rf_CommonCreateSmallWriteDAG(raidPtr, asmap, dag_h, bp, flags, 
+				     allocList, &rf_qFuncs, NULL);
+}
+/* Dead Q - act like a RAID 5 small write */
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_001_CreateSmallWriteDAG)
+{
+	rf_CommonCreateSmallWriteDAG(raidPtr, asmap, dag_h, bp, flags, 
+				     allocList, &rf_pFuncs, NULL);
+}
+/* Dead P - act like a RAID 5 large write but for Q */
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_010_CreateLargeWriteDAG)
+{
+	RF_PhysDiskAddr_t *temp;
+	/* swap P and Q pointers to fake out the code */
+	temp = asmap->parityInfo;
+	asmap->parityInfo = asmap->qInfo;
+	asmap->qInfo = temp;
+	rf_CommonCreateLargeWriteDAG(raidPtr, asmap, dag_h, bp, flags, 
+				     allocList, 1, rf_RegularQFunc, RF_FALSE);
+}
+/* Dead Q - act like a RAID 5 large write */
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_001_CreateLargeWriteDAG)
+{
+	rf_CommonCreateLargeWriteDAG(raidPtr, asmap, dag_h, bp, flags, 
+				     allocList, 1, rf_RegularPFunc, RF_FALSE);
+}
+
+
+/*
+ * writes, double failure
+ */
+
+/*
+ * Lost P & Q - do a nonredundant write
+ */
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_011_CreateWriteDAG)
+{
+	rf_CreateNonRedundantWriteDAG(raidPtr, asmap, dag_h, bp, flags, allocList,
+	    RF_IO_TYPE_WRITE);
+}
+/*
+   In the two cases below,
+   A nasty case arises when the write a (strict) portion of a failed stripe unit
+   and parts of another su. For now, we do not support this.
+*/
+
+/*
+  Lost Data and  P - do a Q write.
+*/
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_110_CreateWriteDAG)
+{
+	RF_PhysDiskAddr_t *temp;
+
+	if (asmap->numStripeUnitsAccessed != 1 &&
+	    asmap->failedPDAs[0]->numSector != raidPtr->Layout.sectorsPerStripeUnit) {
+		RF_PANIC();
+	}
+	/* swap P and Q to fake out parity code */
+	temp = asmap->parityInfo;
+	asmap->parityInfo = asmap->qInfo;
+	asmap->qInfo = temp;
+	rf_CommonCreateSimpleDegradedWriteDAG(raidPtr, asmap, dag_h, bp, flags,
+		      allocList, 1, 
+		      (int (*) (RF_DagNode_t *)) rf_PQ_DegradedWriteQFunc,
+		      RF_FALSE);
+	/* is the regular Q func the right one to call? */
+}
+/*
+   Lost Data and Q - do degraded mode P write
+*/
+RF_CREATE_DAG_FUNC_DECL(rf_PQ_101_CreateWriteDAG)
+{
+	if (asmap->numStripeUnitsAccessed != 1 &&
+	    asmap->failedPDAs[0]->numSector != raidPtr->Layout.sectorsPerStripeUnit)
+		RF_PANIC();
+	rf_CommonCreateSimpleDegradedWriteDAG(raidPtr, asmap, dag_h, bp, flags,
+	    allocList, 1, rf_RecoveryXorFunc, RF_FALSE);
+}
+#endif				/* (RF_INCLUDE_DECL_PQ > 0) ||
+				 * (RF_INCLUDE_RAID6 > 0) */