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diff --git a/sys/dev/raidframe/rf_dagfuncs.c b/sys/dev/raidframe/rf_dagfuncs.c
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+/* $FreeBSD$ */
+/* $NetBSD: rf_dagfuncs.c,v 1.7 2001/02/03 12:51:10 mrg Exp $ */
+/*
+ * Copyright (c) 1995 Carnegie-Mellon University.
+ * All rights reserved.
+ *
+ * Author: Mark Holland, William V. Courtright II
+ *
+ * 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.
+ */
+
+/*
+ * dagfuncs.c -- DAG node execution routines
+ *
+ * Rules:
+ * 1. Every DAG execution function must eventually cause node->status to
+ * get set to "good" or "bad", and "FinishNode" to be called. In the
+ * case of nodes that complete immediately (xor, NullNodeFunc, etc),
+ * the node execution function can do these two things directly. In
+ * the case of nodes that have to wait for some event (a disk read to
+ * complete, a lock to be released, etc) to occur before they can
+ * complete, this is typically achieved by having whatever module
+ * is doing the operation call GenericWakeupFunc upon completion.
+ * 2. DAG execution functions should check the status in the DAG header
+ * and NOP out their operations if the status is not "enable". However,
+ * execution functions that release resources must be sure to release
+ * them even when they NOP out the function that would use them.
+ * Functions that acquire resources should go ahead and acquire them
+ * even when they NOP, so that a downstream release node will not have
+ * to check to find out whether or not the acquire was suppressed.
+ */
+
+#include <sys/param.h>
+#if defined(__NetBSD__)
+#include <sys/ioctl.h>
+#elif defined(__FreeBSD__)
+#include <sys/ioccom.h>
+#include <sys/filio.h>
+#endif
+
+#include <dev/raidframe/rf_archs.h>
+#include <dev/raidframe/rf_raid.h>
+#include <dev/raidframe/rf_dag.h>
+#include <dev/raidframe/rf_layout.h>
+#include <dev/raidframe/rf_etimer.h>
+#include <dev/raidframe/rf_acctrace.h>
+#include <dev/raidframe/rf_diskqueue.h>
+#include <dev/raidframe/rf_dagfuncs.h>
+#include <dev/raidframe/rf_general.h>
+#include <dev/raidframe/rf_engine.h>
+#include <dev/raidframe/rf_dagutils.h>
+
+#include <dev/raidframe/rf_kintf.h>
+
+#if RF_INCLUDE_PARITYLOGGING > 0
+#include <dev/raidframe/rf_paritylog.h>
+#endif /* RF_INCLUDE_PARITYLOGGING > 0 */
+
+int (*rf_DiskReadFunc) (RF_DagNode_t *);
+int (*rf_DiskWriteFunc) (RF_DagNode_t *);
+int (*rf_DiskReadUndoFunc) (RF_DagNode_t *);
+int (*rf_DiskWriteUndoFunc) (RF_DagNode_t *);
+int (*rf_DiskUnlockFunc) (RF_DagNode_t *);
+int (*rf_DiskUnlockUndoFunc) (RF_DagNode_t *);
+int (*rf_RegularXorUndoFunc) (RF_DagNode_t *);
+int (*rf_SimpleXorUndoFunc) (RF_DagNode_t *);
+int (*rf_RecoveryXorUndoFunc) (RF_DagNode_t *);
+
+/*****************************************************************************************
+ * main (only) configuration routine for this module
+ ****************************************************************************************/
+int
+rf_ConfigureDAGFuncs(listp)
+ RF_ShutdownList_t **listp;
+{
+ RF_ASSERT(((sizeof(long) == 8) && RF_LONGSHIFT == 3) || ((sizeof(long) == 4) && RF_LONGSHIFT == 2));
+ rf_DiskReadFunc = rf_DiskReadFuncForThreads;
+ rf_DiskReadUndoFunc = rf_DiskUndoFunc;
+ rf_DiskWriteFunc = rf_DiskWriteFuncForThreads;
+ rf_DiskWriteUndoFunc = rf_DiskUndoFunc;
+ rf_DiskUnlockFunc = rf_DiskUnlockFuncForThreads;
+ rf_DiskUnlockUndoFunc = rf_NullNodeUndoFunc;
+ rf_RegularXorUndoFunc = rf_NullNodeUndoFunc;
+ rf_SimpleXorUndoFunc = rf_NullNodeUndoFunc;
+ rf_RecoveryXorUndoFunc = rf_NullNodeUndoFunc;
+ return (0);
+}
+
+
+
+/*****************************************************************************************
+ * the execution function associated with a terminate node
+ ****************************************************************************************/
+int
+rf_TerminateFunc(node)
+ RF_DagNode_t *node;
+{
+ RF_ASSERT(node->dagHdr->numCommits == node->dagHdr->numCommitNodes);
+ node->status = rf_good;
+ return (rf_FinishNode(node, RF_THREAD_CONTEXT));
+}
+
+int
+rf_TerminateUndoFunc(node)
+ RF_DagNode_t *node;
+{
+ return (0);
+}
+
+
+/*****************************************************************************************
+ * execution functions associated with a mirror node
+ *
+ * parameters:
+ *
+ * 0 - physical disk addres of data
+ * 1 - buffer for holding read data
+ * 2 - parity stripe ID
+ * 3 - flags
+ * 4 - physical disk address of mirror (parity)
+ *
+ ****************************************************************************************/
+
+int
+rf_DiskReadMirrorIdleFunc(node)
+ RF_DagNode_t *node;
+{
+ /* select the mirror copy with the shortest queue and fill in node
+ * parameters with physical disk address */
+
+ rf_SelectMirrorDiskIdle(node);
+ return (rf_DiskReadFunc(node));
+}
+
+int
+rf_DiskReadMirrorPartitionFunc(node)
+ RF_DagNode_t *node;
+{
+ /* select the mirror copy with the shortest queue and fill in node
+ * parameters with physical disk address */
+
+ rf_SelectMirrorDiskPartition(node);
+ return (rf_DiskReadFunc(node));
+}
+
+int
+rf_DiskReadMirrorUndoFunc(node)
+ RF_DagNode_t *node;
+{
+ return (0);
+}
+
+
+
+#if RF_INCLUDE_PARITYLOGGING > 0
+/*****************************************************************************************
+ * the execution function associated with a parity log update node
+ ****************************************************************************************/
+int
+rf_ParityLogUpdateFunc(node)
+ RF_DagNode_t *node;
+{
+ RF_PhysDiskAddr_t *pda = (RF_PhysDiskAddr_t *) node->params[0].p;
+ caddr_t buf = (caddr_t) node->params[1].p;
+ RF_ParityLogData_t *logData;
+ RF_AccTraceEntry_t *tracerec = node->dagHdr->tracerec;
+ RF_Etimer_t timer;
+
+ if (node->dagHdr->status == rf_enable) {
+ RF_ETIMER_START(timer);
+ logData = rf_CreateParityLogData(RF_UPDATE, pda, buf,
+ (RF_Raid_t *) (node->dagHdr->raidPtr),
+ node->wakeFunc, (void *) node,
+ node->dagHdr->tracerec, timer);
+ if (logData)
+ rf_ParityLogAppend(logData, RF_FALSE, NULL, RF_FALSE);
+ else {
+ RF_ETIMER_STOP(timer);
+ RF_ETIMER_EVAL(timer);
+ tracerec->plog_us += RF_ETIMER_VAL_US(timer);
+ (node->wakeFunc) (node, ENOMEM);
+ }
+ }
+ return (0);
+}
+
+
+/*****************************************************************************************
+ * the execution function associated with a parity log overwrite node
+ ****************************************************************************************/
+int
+rf_ParityLogOverwriteFunc(node)
+ RF_DagNode_t *node;
+{
+ RF_PhysDiskAddr_t *pda = (RF_PhysDiskAddr_t *) node->params[0].p;
+ caddr_t buf = (caddr_t) node->params[1].p;
+ RF_ParityLogData_t *logData;
+ RF_AccTraceEntry_t *tracerec = node->dagHdr->tracerec;
+ RF_Etimer_t timer;
+
+ if (node->dagHdr->status == rf_enable) {
+ RF_ETIMER_START(timer);
+ logData = rf_CreateParityLogData(RF_OVERWRITE, pda, buf, (RF_Raid_t *) (node->dagHdr->raidPtr),
+ node->wakeFunc, (void *) node, node->dagHdr->tracerec, timer);
+ if (logData)
+ rf_ParityLogAppend(logData, RF_FALSE, NULL, RF_FALSE);
+ else {
+ RF_ETIMER_STOP(timer);
+ RF_ETIMER_EVAL(timer);
+ tracerec->plog_us += RF_ETIMER_VAL_US(timer);
+ (node->wakeFunc) (node, ENOMEM);
+ }
+ }
+ return (0);
+}
+#else /* RF_INCLUDE_PARITYLOGGING > 0 */
+
+int
+rf_ParityLogUpdateFunc(node)
+ RF_DagNode_t *node;
+{
+ return (0);
+}
+int
+rf_ParityLogOverwriteFunc(node)
+ RF_DagNode_t *node;
+{
+ return (0);
+}
+#endif /* RF_INCLUDE_PARITYLOGGING > 0 */
+
+int
+rf_ParityLogUpdateUndoFunc(node)
+ RF_DagNode_t *node;
+{
+ return (0);
+}
+
+int
+rf_ParityLogOverwriteUndoFunc(node)
+ RF_DagNode_t *node;
+{
+ return (0);
+}
+/*****************************************************************************************
+ * the execution function associated with a NOP node
+ ****************************************************************************************/
+int
+rf_NullNodeFunc(node)
+ RF_DagNode_t *node;
+{
+ node->status = rf_good;
+ return (rf_FinishNode(node, RF_THREAD_CONTEXT));
+}
+
+int
+rf_NullNodeUndoFunc(node)
+ RF_DagNode_t *node;
+{
+ node->status = rf_undone;
+ return (rf_FinishNode(node, RF_THREAD_CONTEXT));
+}
+
+
+/*****************************************************************************************
+ * the execution function associated with a disk-read node
+ ****************************************************************************************/
+int
+rf_DiskReadFuncForThreads(node)
+ RF_DagNode_t *node;
+{
+ RF_DiskQueueData_t *req;
+ RF_PhysDiskAddr_t *pda = (RF_PhysDiskAddr_t *) node->params[0].p;
+ caddr_t buf = (caddr_t) node->params[1].p;
+ RF_StripeNum_t parityStripeID = (RF_StripeNum_t) node->params[2].v;
+ unsigned priority = RF_EXTRACT_PRIORITY(node->params[3].v);
+ unsigned lock = RF_EXTRACT_LOCK_FLAG(node->params[3].v);
+ unsigned unlock = RF_EXTRACT_UNLOCK_FLAG(node->params[3].v);
+ unsigned which_ru = RF_EXTRACT_RU(node->params[3].v);
+ RF_DiskQueueDataFlags_t flags = 0;
+ RF_IoType_t iotype = (node->dagHdr->status == rf_enable) ? RF_IO_TYPE_READ : RF_IO_TYPE_NOP;
+ RF_DiskQueue_t **dqs = ((RF_Raid_t *) (node->dagHdr->raidPtr))->Queues;
+ void *b_proc = NULL;
+
+#if defined(__NetBSD__)
+ if (node->dagHdr->bp)
+ b_proc = (void *) ((RF_Buf_t) node->dagHdr->bp)->b_proc;
+#endif
+
+ RF_ASSERT(!(lock && unlock));
+ flags |= (lock) ? RF_LOCK_DISK_QUEUE : 0;
+ flags |= (unlock) ? RF_UNLOCK_DISK_QUEUE : 0;
+
+ req = rf_CreateDiskQueueData(iotype, pda->startSector, pda->numSector,
+ buf, parityStripeID, which_ru,
+ (int (*) (void *, int)) node->wakeFunc,
+ node, NULL, node->dagHdr->tracerec,
+ (void *) (node->dagHdr->raidPtr), flags, b_proc);
+ if (!req) {
+ (node->wakeFunc) (node, ENOMEM);
+ } else {
+ node->dagFuncData = (void *) req;
+ rf_DiskIOEnqueue(&(dqs[pda->row][pda->col]), req, priority);
+ }
+ return (0);
+}
+
+
+/*****************************************************************************************
+ * the execution function associated with a disk-write node
+ ****************************************************************************************/
+int
+rf_DiskWriteFuncForThreads(node)
+ RF_DagNode_t *node;
+{
+ RF_DiskQueueData_t *req;
+ RF_PhysDiskAddr_t *pda = (RF_PhysDiskAddr_t *) node->params[0].p;
+ caddr_t buf = (caddr_t) node->params[1].p;
+ RF_StripeNum_t parityStripeID = (RF_StripeNum_t) node->params[2].v;
+ unsigned priority = RF_EXTRACT_PRIORITY(node->params[3].v);
+ unsigned lock = RF_EXTRACT_LOCK_FLAG(node->params[3].v);
+ unsigned unlock = RF_EXTRACT_UNLOCK_FLAG(node->params[3].v);
+ unsigned which_ru = RF_EXTRACT_RU(node->params[3].v);
+ RF_DiskQueueDataFlags_t flags = 0;
+ RF_IoType_t iotype = (node->dagHdr->status == rf_enable) ? RF_IO_TYPE_WRITE : RF_IO_TYPE_NOP;
+ RF_DiskQueue_t **dqs = ((RF_Raid_t *) (node->dagHdr->raidPtr))->Queues;
+ void *b_proc = NULL;
+
+#if defined(__NetBSD__)
+ if (node->dagHdr->bp)
+ b_proc = (void *) ((RF_Buf_t) node->dagHdr->bp)->b_proc;
+#endif
+
+ /* normal processing (rollaway or forward recovery) begins here */
+ RF_ASSERT(!(lock && unlock));
+ flags |= (lock) ? RF_LOCK_DISK_QUEUE : 0;
+ flags |= (unlock) ? RF_UNLOCK_DISK_QUEUE : 0;
+ req = rf_CreateDiskQueueData(iotype, pda->startSector, pda->numSector,
+ buf, parityStripeID, which_ru,
+ (int (*) (void *, int)) node->wakeFunc,
+ (void *) node, NULL,
+ node->dagHdr->tracerec,
+ (void *) (node->dagHdr->raidPtr),
+ flags, b_proc);
+
+ if (!req) {
+ (node->wakeFunc) (node, ENOMEM);
+ } else {
+ node->dagFuncData = (void *) req;
+ rf_DiskIOEnqueue(&(dqs[pda->row][pda->col]), req, priority);
+ }
+
+ return (0);
+}
+/*****************************************************************************************
+ * the undo function for disk nodes
+ * Note: this is not a proper undo of a write node, only locks are released.
+ * old data is not restored to disk!
+ ****************************************************************************************/
+int
+rf_DiskUndoFunc(node)
+ RF_DagNode_t *node;
+{
+ RF_DiskQueueData_t *req;
+ RF_PhysDiskAddr_t *pda = (RF_PhysDiskAddr_t *) node->params[0].p;
+ RF_DiskQueue_t **dqs = ((RF_Raid_t *) (node->dagHdr->raidPtr))->Queues;
+
+ req = rf_CreateDiskQueueData(RF_IO_TYPE_NOP,
+ 0L, 0, NULL, 0L, 0,
+ (int (*) (void *, int)) node->wakeFunc,
+ (void *) node,
+ NULL, node->dagHdr->tracerec,
+ (void *) (node->dagHdr->raidPtr),
+ RF_UNLOCK_DISK_QUEUE, NULL);
+ if (!req)
+ (node->wakeFunc) (node, ENOMEM);
+ else {
+ node->dagFuncData = (void *) req;
+ rf_DiskIOEnqueue(&(dqs[pda->row][pda->col]), req, RF_IO_NORMAL_PRIORITY);
+ }
+
+ return (0);
+}
+/*****************************************************************************************
+ * the execution function associated with an "unlock disk queue" node
+ ****************************************************************************************/
+int
+rf_DiskUnlockFuncForThreads(node)
+ RF_DagNode_t *node;
+{
+ RF_DiskQueueData_t *req;
+ RF_PhysDiskAddr_t *pda = (RF_PhysDiskAddr_t *) node->params[0].p;
+ RF_DiskQueue_t **dqs = ((RF_Raid_t *) (node->dagHdr->raidPtr))->Queues;
+
+ req = rf_CreateDiskQueueData(RF_IO_TYPE_NOP,
+ 0L, 0, NULL, 0L, 0,
+ (int (*) (void *, int)) node->wakeFunc,
+ (void *) node,
+ NULL, node->dagHdr->tracerec,
+ (void *) (node->dagHdr->raidPtr),
+ RF_UNLOCK_DISK_QUEUE, NULL);
+ if (!req)
+ (node->wakeFunc) (node, ENOMEM);
+ else {
+ node->dagFuncData = (void *) req;
+ rf_DiskIOEnqueue(&(dqs[pda->row][pda->col]), req, RF_IO_NORMAL_PRIORITY);
+ }
+
+ return (0);
+}
+/*****************************************************************************************
+ * Callback routine for DiskRead and DiskWrite nodes. When the disk op completes,
+ * the routine is called to set the node status and inform the execution engine that
+ * the node has fired.
+ ****************************************************************************************/
+int
+rf_GenericWakeupFunc(node, status)
+ RF_DagNode_t *node;
+ int status;
+{
+ switch (node->status) {
+ case rf_bwd1:
+ node->status = rf_bwd2;
+ if (node->dagFuncData)
+ rf_FreeDiskQueueData((RF_DiskQueueData_t *) node->dagFuncData);
+ return (rf_DiskWriteFuncForThreads(node));
+ break;
+ case rf_fired:
+ if (status)
+ node->status = rf_bad;
+ else
+ node->status = rf_good;
+ break;
+ case rf_recover:
+ /* probably should never reach this case */
+ if (status)
+ node->status = rf_panic;
+ else
+ node->status = rf_undone;
+ break;
+ default:
+ printf("rf_GenericWakeupFunc:");
+ printf("node->status is %d,", node->status);
+ printf("status is %d \n", status);
+ RF_PANIC();
+ break;
+ }
+ if (node->dagFuncData)
+ rf_FreeDiskQueueData((RF_DiskQueueData_t *) node->dagFuncData);
+ return (rf_FinishNode(node, RF_INTR_CONTEXT));
+}
+
+
+/*****************************************************************************************
+ * there are three distinct types of xor nodes
+ * A "regular xor" is used in the fault-free case where the access spans a complete
+ * stripe unit. It assumes that the result buffer is one full stripe unit in size,
+ * and uses the stripe-unit-offset values that it computes from the PDAs to determine
+ * where within the stripe unit to XOR each argument buffer.
+ *
+ * A "simple xor" is used in the fault-free case where the access touches only a portion
+ * of one (or two, in some cases) stripe unit(s). It assumes that all the argument
+ * buffers are of the same size and have the same stripe unit offset.
+ *
+ * A "recovery xor" is used in the degraded-mode case. It's similar to the regular
+ * xor function except that it takes the failed PDA as an additional parameter, and
+ * uses it to determine what portions of the argument buffers need to be xor'd into
+ * the result buffer, and where in the result buffer they should go.
+ ****************************************************************************************/
+
+/* xor the params together and store the result in the result field.
+ * assume the result field points to a buffer that is the size of one SU,
+ * and use the pda params to determine where within the buffer to XOR
+ * the input buffers.
+ */
+int
+rf_RegularXorFunc(node)
+ RF_DagNode_t *node;
+{
+ RF_Raid_t *raidPtr = (RF_Raid_t *) node->params[node->numParams - 1].p;
+ RF_AccTraceEntry_t *tracerec = node->dagHdr->tracerec;
+ RF_Etimer_t timer;
+ int i, retcode;
+
+ retcode = 0;
+ if (node->dagHdr->status == rf_enable) {
+ /* don't do the XOR if the input is the same as the output */
+ RF_ETIMER_START(timer);
+ for (i = 0; i < node->numParams - 1; i += 2)
+ if (node->params[i + 1].p != node->results[0]) {
+ retcode = rf_XorIntoBuffer(raidPtr, (RF_PhysDiskAddr_t *) node->params[i].p,
+ (char *) node->params[i + 1].p, (char *) node->results[0], node->dagHdr->bp);
+ }
+ RF_ETIMER_STOP(timer);
+ RF_ETIMER_EVAL(timer);
+ tracerec->xor_us += RF_ETIMER_VAL_US(timer);
+ }
+ return (rf_GenericWakeupFunc(node, retcode)); /* call wake func
+ * explicitly since no
+ * I/O in this node */
+}
+/* xor the inputs into the result buffer, ignoring placement issues */
+int
+rf_SimpleXorFunc(node)
+ RF_DagNode_t *node;
+{
+ RF_Raid_t *raidPtr = (RF_Raid_t *) node->params[node->numParams - 1].p;
+ int i, retcode = 0;
+ RF_AccTraceEntry_t *tracerec = node->dagHdr->tracerec;
+ RF_Etimer_t timer;
+
+ if (node->dagHdr->status == rf_enable) {
+ RF_ETIMER_START(timer);
+ /* don't do the XOR if the input is the same as the output */
+ for (i = 0; i < node->numParams - 1; i += 2)
+ if (node->params[i + 1].p != node->results[0]) {
+ retcode = rf_bxor((char *)node->params[i + 1].p,
+ (char *)node->results[0],
+ rf_RaidAddressToByte(raidPtr,
+ ((RF_PhysDiskAddr_t *)node->params[i].p)->
+ numSector), (RF_Buf_t)node->dagHdr->bp);
+ }
+ RF_ETIMER_STOP(timer);
+ RF_ETIMER_EVAL(timer);
+ tracerec->xor_us += RF_ETIMER_VAL_US(timer);
+ }
+ return (rf_GenericWakeupFunc(node, retcode)); /* call wake func
+ * explicitly since no
+ * I/O in this node */
+}
+/* this xor is used by the degraded-mode dag functions to recover lost data.
+ * the second-to-last parameter is the PDA for the failed portion of the access.
+ * the code here looks at this PDA and assumes that the xor target buffer is
+ * equal in size to the number of sectors in the failed PDA. It then uses
+ * the other PDAs in the parameter list to determine where within the target
+ * buffer the corresponding data should be xored.
+ */
+int
+rf_RecoveryXorFunc(node)
+ RF_DagNode_t *node;
+{
+ RF_Raid_t *raidPtr = (RF_Raid_t *) node->params[node->numParams - 1].p;
+ RF_RaidLayout_t *layoutPtr = (RF_RaidLayout_t *) & raidPtr->Layout;
+ RF_PhysDiskAddr_t *failedPDA = (RF_PhysDiskAddr_t *) node->params[node->numParams - 2].p;
+ int i, retcode = 0;
+ RF_PhysDiskAddr_t *pda;
+ int suoffset, failedSUOffset = rf_StripeUnitOffset(layoutPtr, failedPDA->startSector);
+ char *srcbuf, *destbuf;
+ RF_AccTraceEntry_t *tracerec = node->dagHdr->tracerec;
+ RF_Etimer_t timer;
+
+ if (node->dagHdr->status == rf_enable) {
+ RF_ETIMER_START(timer);
+ for (i = 0; i < node->numParams - 2; i += 2)
+ if (node->params[i + 1].p != node->results[0]) {
+ pda = (RF_PhysDiskAddr_t *) node->params[i].p;
+ srcbuf = (char *) node->params[i + 1].p;
+ suoffset = rf_StripeUnitOffset(layoutPtr, pda->startSector);
+ destbuf = ((char *) node->results[0]) + rf_RaidAddressToByte(raidPtr, suoffset - failedSUOffset);
+ retcode = rf_bxor(srcbuf, destbuf, rf_RaidAddressToByte(raidPtr, pda->numSector), node->dagHdr->bp);
+ }
+ RF_ETIMER_STOP(timer);
+ RF_ETIMER_EVAL(timer);
+ tracerec->xor_us += RF_ETIMER_VAL_US(timer);
+ }
+ return (rf_GenericWakeupFunc(node, retcode));
+}
+/*****************************************************************************************
+ * The next three functions are utilities used by the above xor-execution functions.
+ ****************************************************************************************/
+
+
+/*
+ * this is just a glorified buffer xor. targbuf points to a buffer that is one full stripe unit
+ * in size. srcbuf points to a buffer that may be less than 1 SU, but never more. When the
+ * access described by pda is one SU in size (which by implication means it's SU-aligned),
+ * all that happens is (targbuf) <- (srcbuf ^ targbuf). When the access is less than one
+ * SU in size the XOR occurs on only the portion of targbuf identified in the pda.
+ */
+
+int
+rf_XorIntoBuffer(raidPtr, pda, srcbuf, targbuf, bp)
+ RF_Raid_t *raidPtr;
+ RF_PhysDiskAddr_t *pda;
+ char *srcbuf;
+ char *targbuf;
+ void *bp;
+{
+ char *targptr;
+ int sectPerSU = raidPtr->Layout.sectorsPerStripeUnit;
+ int SUOffset = pda->startSector % sectPerSU;
+ int length, retcode = 0;
+
+ RF_ASSERT(pda->numSector <= sectPerSU);
+
+ targptr = targbuf + rf_RaidAddressToByte(raidPtr, SUOffset);
+ length = rf_RaidAddressToByte(raidPtr, pda->numSector);
+ retcode = rf_bxor(srcbuf, targptr, length, bp);
+ return (retcode);
+}
+/* it really should be the case that the buffer pointers (returned by malloc)
+ * are aligned to the natural word size of the machine, so this is the only
+ * case we optimize for. The length should always be a multiple of the sector
+ * size, so there should be no problem with leftover bytes at the end.
+ */
+int
+rf_bxor(src, dest, len, bp)
+ char *src;
+ char *dest;
+ int len;
+ void *bp;
+{
+ unsigned mask = sizeof(long) - 1, retcode = 0;
+
+ if (!(((unsigned long) src) & mask) && !(((unsigned long) dest) & mask) && !(len & mask)) {
+ retcode = rf_longword_bxor((unsigned long *) src, (unsigned long *) dest, len >> RF_LONGSHIFT, bp);
+ } else {
+ RF_ASSERT(0);
+ }
+ return (retcode);
+}
+/* map a user buffer into kernel space, if necessary */
+#define REMAP_VA(_bp,x,y) (y) = (x)
+
+/* When XORing in kernel mode, we need to map each user page to kernel space before we can access it.
+ * We don't want to assume anything about which input buffers are in kernel/user
+ * space, nor about their alignment, so in each loop we compute the maximum number
+ * of bytes that we can xor without crossing any page boundaries, and do only this many
+ * bytes before the next remap.
+ */
+int
+rf_longword_bxor(src, dest, len, bp)
+ unsigned long *src;
+ unsigned long *dest;
+ int len; /* longwords */
+ void *bp;
+{
+ unsigned long *end = src + len;
+ unsigned long d0, d1, d2, d3, s0, s1, s2, s3; /* temps */
+ unsigned long *pg_src, *pg_dest; /* per-page source/dest
+ * pointers */
+ int longs_this_time;/* # longwords to xor in the current iteration */
+
+ REMAP_VA(bp, src, pg_src);
+ REMAP_VA(bp, dest, pg_dest);
+ if (!pg_src || !pg_dest)
+ return (EFAULT);
+
+ while (len >= 4) {
+ longs_this_time = RF_MIN(len, RF_MIN(RF_BLIP(pg_src), RF_BLIP(pg_dest)) >> RF_LONGSHIFT); /* note len in longwords */
+ src += longs_this_time;
+ dest += longs_this_time;
+ len -= longs_this_time;
+ while (longs_this_time >= 4) {
+ d0 = pg_dest[0];
+ d1 = pg_dest[1];
+ d2 = pg_dest[2];
+ d3 = pg_dest[3];
+ s0 = pg_src[0];
+ s1 = pg_src[1];
+ s2 = pg_src[2];
+ s3 = pg_src[3];
+ pg_dest[0] = d0 ^ s0;
+ pg_dest[1] = d1 ^ s1;
+ pg_dest[2] = d2 ^ s2;
+ pg_dest[3] = d3 ^ s3;
+ pg_src += 4;
+ pg_dest += 4;
+ longs_this_time -= 4;
+ }
+ while (longs_this_time > 0) { /* cannot cross any page
+ * boundaries here */
+ *pg_dest++ ^= *pg_src++;
+ longs_this_time--;
+ }
+
+ /* either we're done, or we've reached a page boundary on one
+ * (or possibly both) of the pointers */
+ if (len) {
+ if (RF_PAGE_ALIGNED(src))
+ REMAP_VA(bp, src, pg_src);
+ if (RF_PAGE_ALIGNED(dest))
+ REMAP_VA(bp, dest, pg_dest);
+ if (!pg_src || !pg_dest)
+ return (EFAULT);
+ }
+ }
+ while (src < end) {
+ *pg_dest++ ^= *pg_src++;
+ src++;
+ dest++;
+ len--;
+ if (RF_PAGE_ALIGNED(src))
+ REMAP_VA(bp, src, pg_src);
+ if (RF_PAGE_ALIGNED(dest))
+ REMAP_VA(bp, dest, pg_dest);
+ }
+ RF_ASSERT(len == 0);
+ return (0);
+}
+
+
+/*
+ dst = a ^ b ^ c;
+ a may equal dst
+ see comment above longword_bxor
+*/
+int
+rf_longword_bxor3(dst, a, b, c, len, bp)
+ unsigned long *dst;
+ unsigned long *a;
+ unsigned long *b;
+ unsigned long *c;
+ int len; /* length in longwords */
+ void *bp;
+{
+ unsigned long a0, a1, a2, a3, b0, b1, b2, b3;
+ unsigned long *pg_a, *pg_b, *pg_c, *pg_dst; /* per-page source/dest
+ * pointers */
+ int longs_this_time;/* # longs to xor in the current iteration */
+ char dst_is_a = 0;
+
+ REMAP_VA(bp, a, pg_a);
+ REMAP_VA(bp, b, pg_b);
+ REMAP_VA(bp, c, pg_c);
+ if (a == dst) {
+ pg_dst = pg_a;
+ dst_is_a = 1;
+ } else {
+ REMAP_VA(bp, dst, pg_dst);
+ }
+
+ /* align dest to cache line. Can't cross a pg boundary on dst here. */
+ while ((((unsigned long) pg_dst) & 0x1f)) {
+ *pg_dst++ = *pg_a++ ^ *pg_b++ ^ *pg_c++;
+ dst++;
+ a++;
+ b++;
+ c++;
+ if (RF_PAGE_ALIGNED(a)) {
+ REMAP_VA(bp, a, pg_a);
+ if (!pg_a)
+ return (EFAULT);
+ }
+ if (RF_PAGE_ALIGNED(b)) {
+ REMAP_VA(bp, a, pg_b);
+ if (!pg_b)
+ return (EFAULT);
+ }
+ if (RF_PAGE_ALIGNED(c)) {
+ REMAP_VA(bp, a, pg_c);
+ if (!pg_c)
+ return (EFAULT);
+ }
+ len--;
+ }
+
+ while (len > 4) {
+ longs_this_time = RF_MIN(len, RF_MIN(RF_BLIP(a), RF_MIN(RF_BLIP(b), RF_MIN(RF_BLIP(c), RF_BLIP(dst)))) >> RF_LONGSHIFT);
+ a += longs_this_time;
+ b += longs_this_time;
+ c += longs_this_time;
+ dst += longs_this_time;
+ len -= longs_this_time;
+ while (longs_this_time >= 4) {
+ a0 = pg_a[0];
+ longs_this_time -= 4;
+
+ a1 = pg_a[1];
+ a2 = pg_a[2];
+
+ a3 = pg_a[3];
+ pg_a += 4;
+
+ b0 = pg_b[0];
+ b1 = pg_b[1];
+
+ b2 = pg_b[2];
+ b3 = pg_b[3];
+ /* start dual issue */
+ a0 ^= b0;
+ b0 = pg_c[0];
+
+ pg_b += 4;
+ a1 ^= b1;
+
+ a2 ^= b2;
+ a3 ^= b3;
+
+ b1 = pg_c[1];
+ a0 ^= b0;
+
+ b2 = pg_c[2];
+ a1 ^= b1;
+
+ b3 = pg_c[3];
+ a2 ^= b2;
+
+ pg_dst[0] = a0;
+ a3 ^= b3;
+ pg_dst[1] = a1;
+ pg_c += 4;
+ pg_dst[2] = a2;
+ pg_dst[3] = a3;
+ pg_dst += 4;
+ }
+ while (longs_this_time > 0) { /* cannot cross any page
+ * boundaries here */
+ *pg_dst++ = *pg_a++ ^ *pg_b++ ^ *pg_c++;
+ longs_this_time--;
+ }
+
+ if (len) {
+ if (RF_PAGE_ALIGNED(a)) {
+ REMAP_VA(bp, a, pg_a);
+ if (!pg_a)
+ return (EFAULT);
+ if (dst_is_a)
+ pg_dst = pg_a;
+ }
+ if (RF_PAGE_ALIGNED(b)) {
+ REMAP_VA(bp, b, pg_b);
+ if (!pg_b)
+ return (EFAULT);
+ }
+ if (RF_PAGE_ALIGNED(c)) {
+ REMAP_VA(bp, c, pg_c);
+ if (!pg_c)
+ return (EFAULT);
+ }
+ if (!dst_is_a)
+ if (RF_PAGE_ALIGNED(dst)) {
+ REMAP_VA(bp, dst, pg_dst);
+ if (!pg_dst)
+ return (EFAULT);
+ }
+ }
+ }
+ while (len) {
+ *pg_dst++ = *pg_a++ ^ *pg_b++ ^ *pg_c++;
+ dst++;
+ a++;
+ b++;
+ c++;
+ if (RF_PAGE_ALIGNED(a)) {
+ REMAP_VA(bp, a, pg_a);
+ if (!pg_a)
+ return (EFAULT);
+ if (dst_is_a)
+ pg_dst = pg_a;
+ }
+ if (RF_PAGE_ALIGNED(b)) {
+ REMAP_VA(bp, b, pg_b);
+ if (!pg_b)
+ return (EFAULT);
+ }
+ if (RF_PAGE_ALIGNED(c)) {
+ REMAP_VA(bp, c, pg_c);
+ if (!pg_c)
+ return (EFAULT);
+ }
+ if (!dst_is_a)
+ if (RF_PAGE_ALIGNED(dst)) {
+ REMAP_VA(bp, dst, pg_dst);
+ if (!pg_dst)
+ return (EFAULT);
+ }
+ len--;
+ }
+ return (0);
+}
+
+int
+rf_bxor3(dst, a, b, c, len, bp)
+ unsigned char *dst;
+ unsigned char *a;
+ unsigned char *b;
+ unsigned char *c;
+ unsigned long len;
+ void *bp;
+{
+ RF_ASSERT(((RF_UL(dst) | RF_UL(a) | RF_UL(b) | RF_UL(c) | len) & 0x7) == 0);
+
+ return (rf_longword_bxor3((unsigned long *) dst, (unsigned long *) a,
+ (unsigned long *) b, (unsigned long *) c, len >> RF_LONGSHIFT, bp));
+}
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