/* $NetBSD: rf_dagdegrd.c,v 1.33 2022/01/24 09:14:37 andvar Exp $ */
/*
* Copyright (c) 1995 Carnegie-Mellon University.
* All rights reserved.
*
* Author: Mark Holland, Daniel Stodolsky, 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
[email protected]
* 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.
*/
/*
* rf_dagdegrd.c
*
* code for creating degraded read DAGs
*/
#include <sys/cdefs.h>
__KERNEL_RCSID(0, "$NetBSD: rf_dagdegrd.c,v 1.33 2022/01/24 09:14:37 andvar Exp $");
#include <dev/raidframe/raidframevar.h>
#include "rf_archs.h"
#include "rf_raid.h"
#include "rf_dag.h"
#include "rf_dagutils.h"
#include "rf_dagfuncs.h"
#include "rf_debugMem.h"
#include "rf_general.h"
#include "rf_dagdegrd.h"
#include "rf_map.h"
/******************************************************************************
*
* General comments on DAG creation:
*
* All DAGs in this file use roll-away error recovery. Each DAG has a single
* commit node, usually called "Cmt." If an error occurs before the Cmt node
* is reached, the execution engine will halt forward execution and work
* backward through the graph, executing the undo functions. Assuming that
* each node in the graph prior to the Cmt node are undoable and atomic - or -
* does not make changes to permanent state, the graph will fail atomically.
* If an error occurs after the Cmt node executes, the engine will roll-forward
* through the graph, blindly executing nodes until it reaches the end.
* If a graph reaches the end, it is assumed to have completed successfully.
*
* A graph has only 1 Cmt node.
*
*/
/******************************************************************************
*
* The following wrappers map the standard DAG creation interface to the
* DAG creation routines. Additionally, these wrappers enable experimentation
* with new DAG structures by providing an extra level of indirection, allowing
* the DAG creation routines to be replaced at this single point.
*/
void
rf_CreateRaidFiveDegradedReadDAG(RF_Raid_t *raidPtr,
RF_AccessStripeMap_t *asmap,
RF_DagHeader_t *dag_h,
void *bp,
RF_RaidAccessFlags_t flags,
RF_AllocListElem_t *allocList)
{
rf_CreateDegradedReadDAG(raidPtr, asmap, dag_h, bp, flags, allocList,
&rf_xorRecoveryFuncs);
}
/******************************************************************************
*
* DAG creation code begins here
*/
/******************************************************************************
* Create a degraded read DAG for RAID level 1
*
* Hdr -> Nil -> R(p/s)d -> Commit -> Trm
*
* The "Rd" node reads data from the surviving disk in the mirror pair
* Rpd - read of primary copy
* Rsd - read of secondary copy
*
* Parameters: raidPtr - description of the physical array
* asmap - logical & physical addresses for this access
* bp - buffer ptr (for holding write data)
* flags - general flags (e.g. disk locking)
* allocList - list of memory allocated in DAG creation
*****************************************************************************/
void
rf_CreateRaidOneDegradedReadDAG(RF_Raid_t *raidPtr,
RF_AccessStripeMap_t *asmap,
RF_DagHeader_t *dag_h,
void *bp,
RF_RaidAccessFlags_t flags,
RF_AllocListElem_t *allocList)
{
RF_DagNode_t *rdNode, *blockNode, *commitNode, *termNode;
RF_StripeNum_t parityStripeID;
RF_ReconUnitNum_t which_ru;
RF_PhysDiskAddr_t *pda;
int useMirror;
useMirror = 0;
parityStripeID = rf_RaidAddressToParityStripeID(&(raidPtr->Layout),
asmap->raidAddress, &which_ru);
#if RF_DEBUG_DAG
if (rf_dagDebug) {
printf("[Creating RAID level 1 degraded read DAG]\n");
}
#endif
dag_h->creator = "RaidOneDegradedReadDAG";
/* alloc the Wnd nodes and the Wmir node */
if (asmap->numDataFailed == 0)
useMirror = RF_FALSE;
else
useMirror = RF_TRUE;
/* total number of nodes = 1 + (block + commit + terminator) */
rdNode = rf_AllocDAGNode(raidPtr);
rdNode->list_next = dag_h->nodes;
dag_h->nodes = rdNode;
blockNode = rf_AllocDAGNode(raidPtr);
blockNode->list_next = dag_h->nodes;
dag_h->nodes = blockNode;
commitNode = rf_AllocDAGNode(raidPtr);
commitNode->list_next = dag_h->nodes;
dag_h->nodes = commitNode;
termNode = rf_AllocDAGNode(raidPtr);
termNode->list_next = dag_h->nodes;
dag_h->nodes = termNode;
/* this dag can not commit until the commit node is reached. errors
* prior to the commit point imply the dag has failed and must be
* retried */
dag_h->numCommitNodes = 1;
dag_h->numCommits = 0;
dag_h->numSuccedents = 1;
/* initialize the block, commit, and terminator nodes */
rf_InitNode(blockNode, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
NULL, 1, 0, 0, 0, dag_h, "Nil", allocList);
rf_InitNode(commitNode, rf_wait, RF_TRUE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
NULL, 1, 1, 0, 0, dag_h, "Cmt", allocList);
rf_InitNode(termNode, rf_wait, RF_FALSE, rf_TerminateFunc, rf_TerminateUndoFunc,
NULL, 0, 1, 0, 0, dag_h, "Trm", allocList);
pda = asmap->physInfo;
RF_ASSERT(pda != NULL);
/* parityInfo must describe entire parity unit */
RF_ASSERT(asmap->parityInfo->next == NULL);
/* initialize the data node */
if (!useMirror) {
/* read primary copy of data */
rf_InitNode(rdNode, rf_wait, RF_FALSE, rf_DiskReadFunc, rf_DiskReadUndoFunc,
rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, "Rpd", allocList);
rdNode->params[0].p = pda;
rdNode->params[1].p = pda->bufPtr;
rdNode->params[2].v = parityStripeID;
rdNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY,
which_ru);
} else {
/* read secondary copy of data */
rf_InitNode(rdNode, rf_wait, RF_FALSE, rf_DiskReadFunc, rf_DiskReadUndoFunc,
rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, "Rsd", allocList);
rdNode->params[0].p = asmap->parityInfo;
rdNode->params[1].p = pda->bufPtr;
rdNode->params[2].v = parityStripeID;
rdNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY,
which_ru);
}
/* connect header to block node */
RF_ASSERT(dag_h->numSuccedents == 1);
RF_ASSERT(blockNode->numAntecedents == 0);
dag_h->succedents[0] = blockNode;
/* connect block node to rdnode */
RF_ASSERT(blockNode->numSuccedents == 1);
RF_ASSERT(rdNode->numAntecedents == 1);
blockNode->succedents[0] = rdNode;
rdNode->antecedents[0] = blockNode;
rdNode->antType[0] = rf_control;
/* connect rdnode to commit node */
RF_ASSERT(rdNode->numSuccedents == 1);
RF_ASSERT(commitNode->numAntecedents == 1);
rdNode->succedents[0] = commitNode;
commitNode->antecedents[0] = rdNode;
commitNode->antType[0] = rf_control;
/* connect commit node to terminator */
RF_ASSERT(commitNode->numSuccedents == 1);
RF_ASSERT(termNode->numAntecedents == 1);
RF_ASSERT(termNode->numSuccedents == 0);
commitNode->succedents[0] = termNode;
termNode->antecedents[0] = commitNode;
termNode->antType[0] = rf_control;
}
/******************************************************************************
*
* creates a DAG to perform a degraded-mode read of data within one stripe.
* This DAG is as follows:
*
* Hdr -> Block -> Rud -> Xor -> Cmt -> T
* -> Rrd ->
* -> Rp -->
*
* Each R node is a successor of the L node
* One successor arc from each R node goes to C, and the other to X
* There is one Rud for each chunk of surviving user data requested by the
* user, and one Rrd for each chunk of surviving user data _not_ being read by
* the user
* R = read, ud = user data, rd = recovery (surviving) data, p = parity
* X = XOR, C = Commit, T = terminate
*
* The block node guarantees a single source node.
*
* Note: The target buffer for the XOR node is set to the actual user buffer
* where the failed data is supposed to end up. This buffer is zero'd by the
* code here. Thus, if you create a degraded read dag, use it, and then
* re-use, you have to be sure to zero the target buffer prior to the re-use.
*
* The recfunc argument at the end specifies the name and function used for
* the redundancy
* recovery function.
*
*****************************************************************************/
void
rf_CreateDegradedReadDAG(RF_Raid_t *raidPtr, RF_AccessStripeMap_t *asmap,
RF_DagHeader_t *dag_h, void *bp,
RF_RaidAccessFlags_t flags,
RF_AllocListElem_t *allocList,
const RF_RedFuncs_t *recFunc)
{
RF_DagNode_t *rudNodes, *rrdNodes, *xorNode, *blockNode;
RF_DagNode_t *commitNode, *rpNode, *termNode;
RF_DagNode_t *tmpNode, *tmprudNode, *tmprrdNode;
int nRrdNodes, nRudNodes, nXorBufs, i;
int j, paramNum;
RF_SectorCount_t sectorsPerSU;
RF_ReconUnitNum_t which_ru;
char overlappingPDAs[RF_MAXCOL];/* a temporary array of flags */
RF_AccessStripeMapHeader_t *new_asm_h[2];
RF_PhysDiskAddr_t *pda, *parityPDA;
RF_StripeNum_t parityStripeID;
RF_PhysDiskAddr_t *failedPDA;
RF_RaidLayout_t *layoutPtr;
char *rpBuf;
layoutPtr = &(raidPtr->Layout);
/* failedPDA points to the pda within the asm that targets the failed
* disk */
failedPDA = asmap->failedPDAs[0];
parityStripeID = rf_RaidAddressToParityStripeID(layoutPtr,
asmap->raidAddress, &which_ru);
sectorsPerSU = layoutPtr->sectorsPerStripeUnit;
#if RF_DEBUG_DAG
if (rf_dagDebug) {
printf("[Creating degraded read DAG]\n");
}
#endif
RF_ASSERT(asmap->numDataFailed == 1);
dag_h->creator = "DegradedReadDAG";
/*
* generate two ASMs identifying the surviving data we need
* in order to recover the lost data
*/
/* overlappingPDAs array must be zero'd */
memset(overlappingPDAs, 0, RF_MAXCOL);
rf_GenerateFailedAccessASMs(raidPtr, asmap, failedPDA, dag_h, new_asm_h, &nXorBufs,
&rpBuf, overlappingPDAs, allocList);
/*
* create all the nodes at once
*
* -1 because no access is generated for the failed pda
*/
nRudNodes = asmap->numStripeUnitsAccessed - 1;
nRrdNodes = ((new_asm_h[0]) ? new_asm_h[0]->stripeMap->numStripeUnitsAccessed : 0) +
((new_asm_h[1]) ? new_asm_h[1]->stripeMap->numStripeUnitsAccessed : 0);
blockNode = rf_AllocDAGNode(raidPtr);
blockNode->list_next = dag_h->nodes;
dag_h->nodes = blockNode;
commitNode = rf_AllocDAGNode(raidPtr);
commitNode->list_next = dag_h->nodes;
dag_h->nodes = commitNode;
xorNode = rf_AllocDAGNode(raidPtr);
xorNode->list_next = dag_h->nodes;
dag_h->nodes = xorNode;
rpNode = rf_AllocDAGNode(raidPtr);
rpNode->list_next = dag_h->nodes;
dag_h->nodes = rpNode;
termNode = rf_AllocDAGNode(raidPtr);
termNode->list_next = dag_h->nodes;
dag_h->nodes = termNode;
for (i = 0; i < nRudNodes; i++) {
tmpNode = rf_AllocDAGNode(raidPtr);
tmpNode->list_next = dag_h->nodes;
dag_h->nodes = tmpNode;
}
rudNodes = dag_h->nodes;
for (i = 0; i < nRrdNodes; i++) {
tmpNode = rf_AllocDAGNode(raidPtr);
tmpNode->list_next = dag_h->nodes;
dag_h->nodes = tmpNode;
}
rrdNodes = dag_h->nodes;
/* initialize nodes */
dag_h->numCommitNodes = 1;
dag_h->numCommits = 0;
/* this dag can not commit until the commit node is reached errors
* prior to the commit point imply the dag has failed */
dag_h->numSuccedents = 1;
rf_InitNode(blockNode, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
NULL, nRudNodes + nRrdNodes + 1, 0, 0, 0, dag_h, "Nil", allocList);
rf_InitNode(commitNode, rf_wait, RF_TRUE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
NULL, 1, 1, 0, 0, dag_h, "Cmt", allocList);
rf_InitNode(termNode, rf_wait, RF_FALSE, rf_TerminateFunc, rf_TerminateUndoFunc,
NULL, 0, 1, 0, 0, dag_h, "Trm", allocList);
rf_InitNode(xorNode, rf_wait, RF_FALSE, recFunc->simple, rf_NullNodeUndoFunc,
NULL, 1, nRudNodes + nRrdNodes + 1, 2 * nXorBufs + 2, 1, dag_h,
recFunc->SimpleName, allocList);
/* fill in the Rud nodes */
tmprudNode = rudNodes;
for (pda = asmap->physInfo, i = 0; i < nRudNodes; i++, pda = pda->next) {
if (pda == failedPDA) {
i--;
continue;
}
rf_InitNode(tmprudNode, rf_wait, RF_FALSE, rf_DiskReadFunc,
rf_DiskReadUndoFunc, rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h,
"Rud", allocList);
RF_ASSERT(pda);
tmprudNode->params[0].p = pda;
tmprudNode->params[1].p = pda->bufPtr;
tmprudNode->params[2].v = parityStripeID;
tmprudNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
tmprudNode = tmprudNode->list_next;
}
/* fill in the Rrd nodes */
i = 0;
tmprrdNode = rrdNodes;
if (new_asm_h[0]) {
for (pda = new_asm_h[0]->stripeMap->physInfo;
i < new_asm_h[0]->stripeMap->numStripeUnitsAccessed;
i++, pda = pda->next) {
rf_InitNode(tmprrdNode, rf_wait, RF_FALSE, rf_DiskReadFunc,
rf_DiskReadUndoFunc, rf_GenericWakeupFunc, 1, 1, 4, 0,
dag_h, "Rrd", allocList);
RF_ASSERT(pda);
tmprrdNode->params[0].p = pda;
tmprrdNode->params[1].p = pda->bufPtr;
tmprrdNode->params[2].v = parityStripeID;
tmprrdNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
tmprrdNode = tmprrdNode->list_next;
}
}
if (new_asm_h[1]) {
/* tmprrdNode = rrdNodes; */ /* don't set this here -- old code was using i+j, which means
we need to just continue using tmprrdNode for the next 'j' elements. */
for (j = 0, pda = new_asm_h[1]->stripeMap->physInfo;
j < new_asm_h[1]->stripeMap->numStripeUnitsAccessed;
j++, pda = pda->next) {
rf_InitNode(tmprrdNode, rf_wait, RF_FALSE, rf_DiskReadFunc,
rf_DiskReadUndoFunc, rf_GenericWakeupFunc, 1, 1, 4, 0,
dag_h, "Rrd", allocList);
RF_ASSERT(pda);
tmprrdNode->params[0].p = pda;
tmprrdNode->params[1].p = pda->bufPtr;
tmprrdNode->params[2].v = parityStripeID;
tmprrdNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
tmprrdNode = tmprrdNode->list_next;
}
}
/* make a PDA for the parity unit */
parityPDA = rf_AllocPhysDiskAddr(raidPtr);
parityPDA->next = dag_h->pda_cleanup_list;
dag_h->pda_cleanup_list = parityPDA;
parityPDA->col = asmap->parityInfo->col;
parityPDA->startSector = ((asmap->parityInfo->startSector / sectorsPerSU)
* sectorsPerSU) + (failedPDA->startSector % sectorsPerSU);
parityPDA->numSector = failedPDA->numSector;
/* initialize the Rp node */
rf_InitNode(rpNode, rf_wait, RF_FALSE, rf_DiskReadFunc, rf_DiskReadUndoFunc,
rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, "Rp ", allocList);
rpNode->params[0].p = parityPDA;
rpNode->params[1].p = rpBuf;
rpNode->params[2].v = parityStripeID;
rpNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
/*
* the last and nastiest step is to assign all
* the parameters of the Xor node
*/
paramNum = 0;
tmprrdNode = rrdNodes;
for (i = 0; i < nRrdNodes; i++) {
/* all the Rrd nodes need to be xored together */
xorNode->params[paramNum++] = tmprrdNode->params[0];
xorNode->params[paramNum++] = tmprrdNode->params[1];
tmprrdNode = tmprrdNode->list_next;
}
tmprudNode = rudNodes;
for (i = 0; i < nRudNodes; i++) {
/* any Rud nodes that overlap the failed access need to be
* xored in */
if (overlappingPDAs[i]) {
pda = rf_AllocPhysDiskAddr(raidPtr);
memcpy((char *) pda, (char *) tmprudNode->params[0].p, sizeof(RF_PhysDiskAddr_t));
/* add it into the pda_cleanup_list *after* the copy, TYVM */
pda->next = dag_h->pda_cleanup_list;
dag_h->pda_cleanup_list = pda;
rf_RangeRestrictPDA(raidPtr, failedPDA, pda, RF_RESTRICT_DOBUFFER, 0);
xorNode->params[paramNum++].p = pda;
xorNode->params[paramNum++].p = pda->bufPtr;
}
tmprudNode = tmprudNode->list_next;
}
/* install parity pda as last set of params to be xor'd */
xorNode->params[paramNum++].p = parityPDA;
xorNode->params[paramNum++].p = rpBuf;
/*
* the last 2 params to the recovery xor node are
* the failed PDA and the raidPtr
*/
xorNode->params[paramNum++].p = failedPDA;
xorNode->params[paramNum++].p = raidPtr;
RF_ASSERT(paramNum == 2 * nXorBufs + 2);
/*
* The xor node uses results[0] as the target buffer.
* Set pointer and zero the buffer. In the kernel, this
* may be a user buffer in which case we have to remap it.
*/
xorNode->results[0] = failedPDA->bufPtr;
memset(failedPDA->bufPtr, 0, rf_RaidAddressToByte(raidPtr,
failedPDA->numSector));
/* connect nodes to form graph */
/* connect the header to the block node */
RF_ASSERT(dag_h->numSuccedents == 1);
RF_ASSERT(blockNode->numAntecedents == 0);
dag_h->succedents[0] = blockNode;
/* connect the block node to the read nodes */
RF_ASSERT(blockNode->numSuccedents == (1 + nRrdNodes + nRudNodes));
RF_ASSERT(rpNode->numAntecedents == 1);
blockNode->succedents[0] = rpNode;
rpNode->antecedents[0] = blockNode;
rpNode->antType[0] = rf_control;
tmprrdNode = rrdNodes;
for (i = 0; i < nRrdNodes; i++) {
RF_ASSERT(tmprrdNode->numSuccedents == 1);
blockNode->succedents[1 + i] = tmprrdNode;
tmprrdNode->antecedents[0] = blockNode;
tmprrdNode->antType[0] = rf_control;
tmprrdNode = tmprrdNode->list_next;
}
tmprudNode = rudNodes;
for (i = 0; i < nRudNodes; i++) {
RF_ASSERT(tmprudNode->numSuccedents == 1);
blockNode->succedents[1 + nRrdNodes + i] = tmprudNode;
tmprudNode->antecedents[0] = blockNode;
tmprudNode->antType[0] = rf_control;
tmprudNode = tmprudNode->list_next;
}
/* connect the read nodes to the xor node */
RF_ASSERT(xorNode->numAntecedents == (1 + nRrdNodes + nRudNodes));
RF_ASSERT(rpNode->numSuccedents == 1);
rpNode->succedents[0] = xorNode;
xorNode->antecedents[0] = rpNode;
xorNode->antType[0] = rf_trueData;
tmprrdNode = rrdNodes;
for (i = 0; i < nRrdNodes; i++) {
RF_ASSERT(tmprrdNode->numSuccedents == 1);
tmprrdNode->succedents[0] = xorNode;
xorNode->antecedents[1 + i] = tmprrdNode;
xorNode->antType[1 + i] = rf_trueData;
tmprrdNode = tmprrdNode->list_next;
}
tmprudNode = rudNodes;
for (i = 0; i < nRudNodes; i++) {
RF_ASSERT(tmprudNode->numSuccedents == 1);
tmprudNode->succedents[0] = xorNode;
xorNode->antecedents[1 + nRrdNodes + i] = tmprudNode;
xorNode->antType[1 + nRrdNodes + i] = rf_trueData;
tmprudNode = tmprudNode->list_next;
}
/* connect the xor node to the commit node */
RF_ASSERT(xorNode->numSuccedents == 1);
RF_ASSERT(commitNode->numAntecedents == 1);
xorNode->succedents[0] = commitNode;
commitNode->antecedents[0] = xorNode;
commitNode->antType[0] = rf_control;
/* connect the termNode to the commit node */
RF_ASSERT(commitNode->numSuccedents == 1);
RF_ASSERT(termNode->numAntecedents == 1);
RF_ASSERT(termNode->numSuccedents == 0);
commitNode->succedents[0] = termNode;
termNode->antType[0] = rf_control;
termNode->antecedents[0] = commitNode;
}
#if (RF_INCLUDE_CHAINDECLUSTER > 0)
/******************************************************************************
* Create a degraded read DAG for Chained Declustering
*
* Hdr -> Nil -> R(p/s)d -> Cmt -> Trm
*
* The "Rd" node reads data from the surviving disk in the mirror pair
* Rpd - read of primary copy
* Rsd - read of secondary copy
*
* Parameters: raidPtr - description of the physical array
* asmap - logical & physical addresses for this access
* bp - buffer ptr (for holding write data)
* flags - general flags (e.g. disk locking)
* allocList - list of memory allocated in DAG creation
*****************************************************************************/
void
rf_CreateRaidCDegradedReadDAG(RF_Raid_t *raidPtr, RF_AccessStripeMap_t *asmap,
RF_DagHeader_t *dag_h, void *bp,
RF_RaidAccessFlags_t flags,
RF_AllocListElem_t *allocList)
{
RF_DagNode_t *nodes, *rdNode, *blockNode, *commitNode, *termNode;
RF_StripeNum_t parityStripeID;
int useMirror, i, shiftable;
RF_ReconUnitNum_t which_ru;
RF_PhysDiskAddr_t *pda;
if ((asmap->numDataFailed + asmap->numParityFailed) == 0) {
shiftable = RF_TRUE;
} else {
shiftable = RF_FALSE;
}
useMirror = 0;
parityStripeID = rf_RaidAddressToParityStripeID(&(raidPtr->Layout),
asmap->raidAddress, &which_ru);
#if RF_DEBUG_DAG
if (rf_dagDebug) {
printf("[Creating RAID C degraded read DAG]\n");
}
#endif
dag_h->creator = "RaidCDegradedReadDAG";
/* alloc the Wnd nodes and the Wmir node */
if (asmap->numDataFailed == 0)
useMirror = RF_FALSE;
else
useMirror = RF_TRUE;
/* total number of nodes = 1 + (block + commit + terminator) */
nodes = RF_MallocAndAdd(4 * sizeof(*nodes), allocList);
i = 0;
rdNode = &nodes[i];
i++;
blockNode = &nodes[i];
i++;
commitNode = &nodes[i];
i++;
termNode = &nodes[i];
i++;
/*
* This dag can not commit until the commit node is reached.
* Errors prior to the commit point imply the dag has failed
* and must be retried.
*/
dag_h->numCommitNodes = 1;
dag_h->numCommits = 0;
dag_h->numSuccedents = 1;
/* initialize the block, commit, and terminator nodes */
rf_InitNode(blockNode, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
NULL, 1, 0, 0, 0, dag_h, "Nil", allocList);
rf_InitNode(commitNode, rf_wait, RF_TRUE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
NULL, 1, 1, 0, 0, dag_h, "Cmt", allocList);
rf_InitNode(termNode, rf_wait, RF_FALSE, rf_TerminateFunc, rf_TerminateUndoFunc,
NULL, 0, 1, 0, 0, dag_h, "Trm", allocList);
pda = asmap->physInfo;
RF_ASSERT(pda != NULL);
/* parityInfo must describe entire parity unit */
RF_ASSERT(asmap->parityInfo->next == NULL);
/* initialize the data node */
if (!useMirror) {
rf_InitNode(rdNode, rf_wait, RF_FALSE, rf_DiskReadFunc, rf_DiskReadUndoFunc,
rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, "Rpd", allocList);
if (shiftable && rf_compute_workload_shift(raidPtr, pda)) {
/* shift this read to the next disk in line */
rdNode->params[0].p = asmap->parityInfo;
rdNode->params[1].p = pda->bufPtr;
rdNode->params[2].v = parityStripeID;
rdNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
} else {
/* read primary copy */
rdNode->params[0].p = pda;
rdNode->params[1].p = pda->bufPtr;
rdNode->params[2].v = parityStripeID;
rdNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
}
} else {
/* read secondary copy of data */
rf_InitNode(rdNode, rf_wait, RF_FALSE, rf_DiskReadFunc, rf_DiskReadUndoFunc,
rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, "Rsd", allocList);
rdNode->params[0].p = asmap->parityInfo;
rdNode->params[1].p = pda->bufPtr;
rdNode->params[2].v = parityStripeID;
rdNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
}
/* connect header to block node */
RF_ASSERT(dag_h->numSuccedents == 1);
RF_ASSERT(blockNode->numAntecedents == 0);
dag_h->succedents[0] = blockNode;
/* connect block node to rdnode */
RF_ASSERT(blockNode->numSuccedents == 1);
RF_ASSERT(rdNode->numAntecedents == 1);
blockNode->succedents[0] = rdNode;
rdNode->antecedents[0] = blockNode;
rdNode->antType[0] = rf_control;
/* connect rdnode to commit node */
RF_ASSERT(rdNode->numSuccedents == 1);
RF_ASSERT(commitNode->numAntecedents == 1);
rdNode->succedents[0] = commitNode;
commitNode->antecedents[0] = rdNode;
commitNode->antType[0] = rf_control;
/* connect commit node to terminator */
RF_ASSERT(commitNode->numSuccedents == 1);
RF_ASSERT(termNode->numAntecedents == 1);
RF_ASSERT(termNode->numSuccedents == 0);
commitNode->succedents[0] = termNode;
termNode->antecedents[0] = commitNode;
termNode->antType[0] = rf_control;
}
#endif /* (RF_INCLUDE_CHAINDECLUSTER > 0) */
#if (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0) || (RF_INCLUDE_EVENODD > 0)
/*
* XXX move this elsewhere?
*/
void
rf_DD_GenerateFailedAccessASMs(RF_Raid_t *raidPtr, RF_AccessStripeMap_t *asmap,
RF_PhysDiskAddr_t **pdap, int *nNodep,
RF_PhysDiskAddr_t **pqpdap, int *nPQNodep,
RF_AllocListElem_t *allocList)
{
RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout);
int PDAPerDisk, i;
RF_SectorCount_t secPerSU = layoutPtr->sectorsPerStripeUnit;
int numDataCol = layoutPtr->numDataCol;
int state;
RF_SectorNum_t suoff, suend;
unsigned firstDataCol, napdas, count;
RF_SectorNum_t fone_start, fone_end, ftwo_start = 0, ftwo_end = 0;
RF_PhysDiskAddr_t *fone = asmap->failedPDAs[0], *ftwo = asmap->failedPDAs[1];
RF_PhysDiskAddr_t *pda_p;
RF_PhysDiskAddr_t *phys_p;
RF_RaidAddr_t sosAddr;
/* determine how many pda's we will have to generate per unaccess
* stripe. If there is only one failed data unit, it is one; if two,
* possibly two, depending whether they overlap. */
fone_start = rf_StripeUnitOffset(layoutPtr, fone->startSector);
fone_end = fone_start + fone->numSector;
#define BUF_ALLOC(num) \
RF_MallocAndAdd(rf_RaidAddressToByte(raidPtr, num), allocList)
#define CONS_PDA(if,start,num) \
pda_p->col = asmap->if->col; \
pda_p->startSector = ((asmap->if->startSector / secPerSU) * secPerSU) + start; \
pda_p->numSector = num; \
pda_p->next = NULL; \
pda_p->bufPtr = BUF_ALLOC(num)
if (asmap->numDataFailed == 1) {
PDAPerDisk = 1;
state = 1;
*pqpdap = RF_MallocAndAdd(2 * sizeof(**pqpdap), allocList);
pda_p = *pqpdap;
/* build p */
CONS_PDA(parityInfo, fone_start, fone->numSector);
pda_p->type = RF_PDA_TYPE_PARITY;
pda_p++;
/* build q */
CONS_PDA(qInfo, fone_start, fone->numSector);
pda_p->type = RF_PDA_TYPE_Q;
} else {
ftwo_start = rf_StripeUnitOffset(layoutPtr, ftwo->startSector);
ftwo_end = ftwo_start + ftwo->numSector;
if (fone->numSector + ftwo->numSector > secPerSU) {
PDAPerDisk = 1;
state = 2;
*pqpdap = RF_MallocAndAdd(2 * sizeof(**pqpdap), allocList);
pda_p = *pqpdap;
CONS_PDA(parityInfo, 0, secPerSU);
pda_p->type = RF_PDA_TYPE_PARITY;
pda_p++;
CONS_PDA(qInfo, 0, secPerSU);
pda_p->type = RF_PDA_TYPE_Q;
} else {
PDAPerDisk = 2;
state = 3;
/* four of them, fone, then ftwo */
*pqpdap = RF_MallocAndAdd(4 * sizeof(**pqpdap), allocList);
pda_p = *pqpdap;
CONS_PDA(parityInfo, fone_start, fone->numSector);
pda_p->type = RF_PDA_TYPE_PARITY;
pda_p++;
CONS_PDA(qInfo, fone_start, fone->numSector);
pda_p->type = RF_PDA_TYPE_Q;
pda_p++;
CONS_PDA(parityInfo, ftwo_start, ftwo->numSector);
pda_p->type = RF_PDA_TYPE_PARITY;
pda_p++;
CONS_PDA(qInfo, ftwo_start, ftwo->numSector);
pda_p->type = RF_PDA_TYPE_Q;
}
}
/* figure out number of nonaccessed pda */
napdas = PDAPerDisk * (numDataCol - asmap->numStripeUnitsAccessed - (ftwo == NULL ? 1 : 0));
*nPQNodep = PDAPerDisk;
/* sweep over the over accessed pda's, figuring out the number of
* additional pda's to generate. Of course, skip the failed ones */
count = 0;
for (pda_p = asmap->physInfo; pda_p; pda_p = pda_p->next) {
if ((pda_p == fone) || (pda_p == ftwo))
continue;
suoff = rf_StripeUnitOffset(layoutPtr, pda_p->startSector);
suend = suoff + pda_p->numSector;
switch (state) {
case 1: /* one failed PDA to overlap */
/* if a PDA doesn't contain the failed unit, it can
* only miss the start or end, not both */
if ((suoff > fone_start) || (suend < fone_end))
count++;
break;
case 2: /* whole stripe */
if (suoff) /* leak at beginning */
count++;
if (suend < numDataCol) /* leak at end */
count++;
break;
case 3: /* two disjoint units */
if ((suoff > fone_start) || (suend < fone_end))
count++;
if ((suoff > ftwo_start) || (suend < ftwo_end))
count++;
break;
default:
RF_PANIC();
}
}
napdas += count;
*nNodep = napdas;
if (napdas == 0)
return; /* short circuit */
/* allocate up our list of pda's */
pda_p = RF_MallocAndAdd(napdas * sizeof(*pdap), allocList);
*pdap = pda_p;
/* linkem together */
for (i = 0; i < (napdas - 1); i++)
pda_p[i].next = pda_p + (i + 1);
/* march through the one's up to the first accessed disk */
firstDataCol = rf_RaidAddressToStripeUnitID(&(raidPtr->Layout), asmap->physInfo->raidAddress) % numDataCol;
sosAddr = rf_RaidAddressOfPrevStripeBoundary(layoutPtr, asmap->raidAddress);
for (i = 0; i < firstDataCol; i++) {
if ((pda_p - (*pdap)) == napdas)
continue;
pda_p->type = RF_PDA_TYPE_DATA;
pda_p->raidAddress = sosAddr + (i * secPerSU);
(raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
/* skip over dead disks */
if (RF_DEAD_DISK(raidPtr->Disks[pda_p->col].status))
continue;
switch (state) {
case 1: /* fone */
pda_p->numSector = fone->numSector;
pda_p->raidAddress += fone_start;
pda_p->startSector += fone_start;
pda_p->bufPtr = BUF_ALLOC(pda_p->numSector);
break;
case 2: /* full stripe */
pda_p->numSector = secPerSU;
pda_p->bufPtr = BUF_ALLOC(secPerSU);
break;
case 3: /* two slabs */
pda_p->numSector = fone->numSector;
pda_p->raidAddress += fone_start;
pda_p->startSector += fone_start;
pda_p->bufPtr = BUF_ALLOC(pda_p->numSector);
pda_p++;
pda_p->type = RF_PDA_TYPE_DATA;
pda_p->raidAddress = sosAddr + (i * secPerSU);
(raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
pda_p->numSector = ftwo->numSector;
pda_p->raidAddress += ftwo_start;
pda_p->startSector += ftwo_start;
pda_p->bufPtr = BUF_ALLOC(pda_p->numSector);
break;
default:
RF_PANIC();
}
pda_p++;
}
/* march through the touched stripe units */
for (phys_p = asmap->physInfo; phys_p; phys_p = phys_p->next, i++) {
if ((phys_p == asmap->failedPDAs[0]) || (phys_p == asmap->failedPDAs[1]))
continue;
suoff = rf_StripeUnitOffset(layoutPtr, phys_p->startSector);
suend = suoff + phys_p->numSector;
switch (state) {
case 1: /* single buffer */
if (suoff > fone_start) {
RF_ASSERT(suend >= fone_end);
/* The data read starts after the mapped
* access, snip off the beginning */
pda_p->numSector = suoff - fone_start;
pda_p->raidAddress = sosAddr + (i * secPerSU) + fone_start;
(raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
pda_p->bufPtr = BUF_ALLOC(pda_p->numSector);
pda_p++;
}
if (suend < fone_end) {
RF_ASSERT(suoff <= fone_start);
/* The data read stops before the end of the
* failed access, extend */
pda_p->numSector = fone_end - suend;
pda_p->raidAddress = sosAddr + (i * secPerSU) + suend; /* off by one? */
(raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
pda_p->bufPtr = BUF_ALLOC(pda_p->numSector);
pda_p++;
}
break;
case 2: /* whole stripe unit */
RF_ASSERT((suoff == 0) || (suend == secPerSU));
if (suend < secPerSU) { /* short read, snip from end
* on */
pda_p->numSector = secPerSU - suend;
pda_p->raidAddress = sosAddr + (i * secPerSU) + suend; /* off by one? */
(raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
pda_p->bufPtr = BUF_ALLOC(pda_p->numSector);
pda_p++;
} else
if (suoff > 0) { /* short at front */
pda_p->numSector = suoff;
pda_p->raidAddress = sosAddr + (i * secPerSU);
(raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
pda_p->bufPtr =
BUF_ALLOC(pda_p->numSector);
pda_p++;
}
break;
case 3: /* two nonoverlapping failures */
if ((suoff > fone_start) || (suend < fone_end)) {
if (suoff > fone_start) {
RF_ASSERT(suend >= fone_end);
/* The data read starts after the
* mapped access, snip off the
* beginning */
pda_p->numSector = suoff - fone_start;
pda_p->raidAddress = sosAddr + (i * secPerSU) + fone_start;
(raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
pda_p->bufPtr =
BUF_ALLOC(pda_p->numSector);
pda_p++;
}
if (suend < fone_end) {
RF_ASSERT(suoff <= fone_start);
/* The data read stops before the end
* of the failed access, extend */
pda_p->numSector = fone_end - suend;
pda_p->raidAddress = sosAddr + (i * secPerSU) + suend; /* off by one? */
(raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
pda_p->bufPtr =
BUF_ALLOC(pda_p->numSector);
pda_p++;
}
}
if ((suoff > ftwo_start) || (suend < ftwo_end)) {
if (suoff > ftwo_start) {
RF_ASSERT(suend >= ftwo_end);
/* The data read starts after the
* mapped access, snip off the
* beginning */
pda_p->numSector = suoff - ftwo_start;
pda_p->raidAddress = sosAddr + (i * secPerSU) + ftwo_start;
(raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
pda_p->bufPtr =
BUF_ALLOC(pda_p->numSector);
pda_p++;
}
if (suend < ftwo_end) {
RF_ASSERT(suoff <= ftwo_start);
/* The data read stops before the end
* of the failed access, extend */
pda_p->numSector = ftwo_end - suend;
pda_p->raidAddress = sosAddr + (i * secPerSU) + suend; /* off by one? */
(raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
pda_p->bufPtr =
BUF_ALLOC(pda_p->numSector);
pda_p++;
}
}
break;
default:
RF_PANIC();
}
}
/* after the last accessed disk */
for (; i < numDataCol; i++) {
if ((pda_p - (*pdap)) == napdas)
continue;
pda_p->type = RF_PDA_TYPE_DATA;
pda_p->raidAddress = sosAddr + (i * secPerSU);
(raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
/* skip over dead disks */
if (RF_DEAD_DISK(raidPtr->Disks[pda_p->col].status))
continue;
switch (state) {
case 1: /* fone */
pda_p->numSector = fone->numSector;
pda_p->raidAddress += fone_start;
pda_p->startSector += fone_start;
pda_p->bufPtr = BUF_ALLOC(pda_p->numSector);
break;
case 2: /* full stripe */
pda_p->numSector = secPerSU;
pda_p->bufPtr = BUF_ALLOC(secPerSU);
break;
case 3: /* two slabs */
pda_p->numSector = fone->numSector;
pda_p->raidAddress += fone_start;
pda_p->startSector += fone_start;
pda_p->bufPtr = BUF_ALLOC(pda_p->numSector);
pda_p++;
pda_p->type = RF_PDA_TYPE_DATA;
pda_p->raidAddress = sosAddr + (i * secPerSU);
(raidPtr->Layout.map->MapSector) (raidPtr, pda_p->raidAddress, &(pda_p->col), &(pda_p->startSector), 0);
pda_p->numSector = ftwo->numSector;
pda_p->raidAddress += ftwo_start;
pda_p->startSector += ftwo_start;
pda_p->bufPtr = BUF_ALLOC(pda_p->numSector);
break;
default:
RF_PANIC();
}
pda_p++;
}
RF_ASSERT(pda_p - *pdap == napdas);
return;
}
#define INIT_DISK_NODE(node,name) \
rf_InitNode(node, rf_wait, RF_FALSE, rf_DiskReadFunc, rf_DiskReadUndoFunc, rf_GenericWakeupFunc, 2,1,4,0, dag_h, name, allocList); \
(node)->succedents[0] = unblockNode; \
(node)->succedents[1] = recoveryNode; \
(node)->antecedents[0] = blockNode; \
(node)->antType[0] = rf_control
#define DISK_NODE_PARAMS(_node_,_p_) \
(_node_).params[0].p = _p_ ; \
(_node_).params[1].p = (_p_)->bufPtr; \
(_node_).params[2].v = parityStripeID; \
(_node_).params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru)
void
rf_DoubleDegRead(RF_Raid_t *raidPtr, RF_AccessStripeMap_t *asmap,
RF_DagHeader_t *dag_h, void *bp,
RF_RaidAccessFlags_t flags,
RF_AllocListElem_t *allocList,
const char *redundantReadNodeName,
const char *recoveryNodeName,
void (*recovFunc) (RF_DagNode_t *))
{
RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout);
RF_DagNode_t *nodes, *rudNodes, *rrdNodes, *recoveryNode, *blockNode,
*unblockNode, *rpNodes, *rqNodes, *termNode;
RF_PhysDiskAddr_t *pda, *pqPDAs;
RF_PhysDiskAddr_t *npdas;
int nNodes, nRrdNodes, nRudNodes, i;
RF_ReconUnitNum_t which_ru;
int nReadNodes, nPQNodes;
RF_PhysDiskAddr_t *failedPDA = asmap->failedPDAs[0];
RF_PhysDiskAddr_t *failedPDAtwo = asmap->failedPDAs[1];
RF_StripeNum_t parityStripeID = rf_RaidAddressToParityStripeID(layoutPtr, asmap->raidAddress, &which_ru);
#if RF_DEBUG_DAG
if (rf_dagDebug)
printf("[Creating Double Degraded Read DAG]\n");
#endif
rf_DD_GenerateFailedAccessASMs(raidPtr, asmap, &npdas, &nRrdNodes, &pqPDAs, &nPQNodes, allocList);
nRudNodes = asmap->numStripeUnitsAccessed - (asmap->numDataFailed);
nReadNodes = nRrdNodes + nRudNodes + 2 * nPQNodes;
nNodes = 4 /* block, unblock, recovery, term */ + nReadNodes;
nodes = RF_MallocAndAdd(nNodes * sizeof(*nodes), allocList);
i = 0;
blockNode = &nodes[i];
i += 1;
unblockNode = &nodes[i];
i += 1;
recoveryNode = &nodes[i];
i += 1;
termNode = &nodes[i];
i += 1;
rudNodes = &nodes[i];
i += nRudNodes;
rrdNodes = &nodes[i];
i += nRrdNodes;
rpNodes = &nodes[i];
i += nPQNodes;
rqNodes = &nodes[i];
i += nPQNodes;
RF_ASSERT(i == nNodes);
dag_h->numSuccedents = 1;
dag_h->succedents[0] = blockNode;
dag_h->creator = "DoubleDegRead";
dag_h->numCommits = 0;
dag_h->numCommitNodes = 1; /* unblock */
rf_InitNode(termNode, rf_wait, RF_FALSE, rf_TerminateFunc, rf_TerminateUndoFunc, NULL, 0, 2, 0, 0, dag_h, "Trm", allocList);
termNode->antecedents[0] = unblockNode;
termNode->antType[0] = rf_control;
termNode->antecedents[1] = recoveryNode;
termNode->antType[1] = rf_control;
/* init the block and unblock nodes */
/* The block node has all nodes except itself, unblock and recovery as
* successors. Similarly for predecessors of the unblock. */
rf_InitNode(blockNode, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc, NULL, nReadNodes, 0, 0, 0, dag_h, "Nil", allocList);
rf_InitNode(unblockNode, rf_wait, RF_TRUE, rf_NullNodeFunc, rf_NullNodeUndoFunc, NULL, 1, nReadNodes, 0, 0, dag_h, "Nil", allocList);
for (i = 0; i < nReadNodes; i++) {
blockNode->succedents[i] = rudNodes + i;
unblockNode->antecedents[i] = rudNodes + i;
unblockNode->antType[i] = rf_control;
}
unblockNode->succedents[0] = termNode;
/* The recovery node has all the reads as predecessors, and the term
* node as successors. It gets a pda as a param from each of the read
* nodes plus the raidPtr. For each failed unit is has a result pda. */
rf_InitNode(recoveryNode, rf_wait, RF_FALSE, recovFunc, rf_NullNodeUndoFunc, NULL,
1, /* succesors */
nReadNodes, /* preds */
nReadNodes + 2, /* params */
asmap->numDataFailed, /* results */
dag_h, recoveryNodeName, allocList);
recoveryNode->succedents[0] = termNode;
for (i = 0; i < nReadNodes; i++) {
recoveryNode->antecedents[i] = rudNodes + i;
recoveryNode->antType[i] = rf_trueData;
}
/* build the read nodes, then come back and fill in recovery params
* and results */
pda = asmap->physInfo;
for (i = 0; i < nRudNodes; pda = pda->next) {
if ((pda == failedPDA) || (pda == failedPDAtwo))
continue;
INIT_DISK_NODE(rudNodes + i, "Rud");
RF_ASSERT(pda);
DISK_NODE_PARAMS(rudNodes[i], pda);
i++;
}
pda = npdas;
for (i = 0; i < nRrdNodes; i++, pda = pda->next) {
INIT_DISK_NODE(rrdNodes + i, "Rrd");
RF_ASSERT(pda);
DISK_NODE_PARAMS(rrdNodes[i], pda);
}
/* redundancy pdas */
pda = pqPDAs;
INIT_DISK_NODE(rpNodes, "Rp");
RF_ASSERT(pda);
DISK_NODE_PARAMS(rpNodes[0], pda);
pda++;
INIT_DISK_NODE(rqNodes, redundantReadNodeName);
RF_ASSERT(pda);
DISK_NODE_PARAMS(rqNodes[0], pda);
if (nPQNodes == 2) {
pda++;
INIT_DISK_NODE(rpNodes + 1, "Rp");
RF_ASSERT(pda);
DISK_NODE_PARAMS(rpNodes[1], pda);
pda++;
INIT_DISK_NODE(rqNodes + 1, redundantReadNodeName);
RF_ASSERT(pda);
DISK_NODE_PARAMS(rqNodes[1], pda);
}
/* fill in recovery node params */
for (i = 0; i < nReadNodes; i++)
recoveryNode->params[i] = rudNodes[i].params[0]; /* pda */
recoveryNode->params[i++].p = (void *) raidPtr;
recoveryNode->params[i++].p = (void *) asmap;
recoveryNode->results[0] = failedPDA;
if (asmap->numDataFailed == 2)
recoveryNode->results[1] = failedPDAtwo;
/* zero fill the target data buffers? */
}
#endif /* (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0) || (RF_INCLUDE_EVENODD > 0) */
