/* $OpenBSD: rf_dagdegrd.c,v 1.6 2006/07/09 22:10:05 mk Exp $ */
/* $NetBSD: rf_dagdegrd.c,v 1.5 2000/01/07 03:40:57 oster 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 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.
*/
/*
* rf_dagdegrd.c
*
* Code for creating degraded read DAGs.
*/
#include "rf_types.h"
#include "rf_raid.h"
#include "rf_dag.h"
#include "rf_dagutils.h"
#include "rf_dagfuncs.h"
#include "rf_debugMem.h"
#include "rf_memchunk.h"
#include "rf_general.h"
#include "rf_dagdegrd.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 *nodes, *rdNode, *blockNode, *commitNode, *termNode;
RF_StripeNum_t parityStripeID;
RF_ReconUnitNum_t which_ru;
RF_PhysDiskAddr_t *pda;
int useMirror, i;
useMirror = 0;
parityStripeID = rf_RaidAddressToParityStripeID(&(raidPtr->Layout),
asmap->raidAddress, &which_ru);
if (rf_dagDebug) {
printf("[Creating RAID level 1 degraded read DAG]\n");
}
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). */
RF_CallocAndAdd(nodes, 4, sizeof(RF_DagNode_t), (RF_DagNode_t *),
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) {
/* 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,
0, 0, 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,
0, 0, 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;
}
/*****************************************************************************
*
* Create 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,
RF_RedFuncs_t *recFunc)
{
RF_DagNode_t *nodes, *rudNodes, *rrdNodes, *xorNode, *blockNode;
RF_DagNode_t *commitNode, *rpNode, *termNode;
int nNodes, nRrdNodes, nRudNodes, nXorBufs, i;
int j, paramNum;
RF_SectorCount_t sectorsPerSU;
RF_ReconUnitNum_t which_ru;
char *overlappingPDAs; /* 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_dagDebug) {
printf("[Creating degraded read DAG]\n");
}
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. */
RF_Calloc(overlappingPDAs, asmap->numStripeUnitsAccessed,
sizeof(char), (char *));
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);
nNodes = 5 + nRudNodes + nRrdNodes; /*
* lock, unlock, xor, Rp,
* Rud, Rrd
*/
RF_CallocAndAdd(nodes, nNodes, sizeof(RF_DagNode_t), (RF_DagNode_t *),
allocList);
i = 0;
blockNode = &nodes[i];
i++;
commitNode = &nodes[i];
i++;
xorNode = &nodes[i];
i++;
rpNode = &nodes[i];
i++;
termNode = &nodes[i];
i++;
rudNodes = &nodes[i];
i += nRudNodes;
rrdNodes = &nodes[i];
i += nRrdNodes;
RF_ASSERT(i == nNodes);
/* 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. */
for (pda = asmap->physInfo, i = 0; i < nRudNodes;
i++, pda = pda->next) {
if (pda == failedPDA) {
i--;
continue;
}
rf_InitNode(&rudNodes[i], rf_wait, RF_FALSE, rf_DiskReadFunc,
rf_DiskReadUndoFunc, rf_GenericWakeupFunc, 1, 1, 4, 0,
dag_h, "Rud", allocList);
RF_ASSERT(pda);
rudNodes[i].params[0].p = pda;
rudNodes[i].params[1].p = pda->bufPtr;
rudNodes[i].params[2].v = parityStripeID;
rudNodes[i].params[3].v =
RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, 0, 0, which_ru);
}
/* Fill in the Rrd nodes. */
i = 0;
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(&rrdNodes[i], rf_wait, RF_FALSE,
rf_DiskReadFunc, rf_DiskReadUndoFunc,
rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h,
"Rrd", allocList);
RF_ASSERT(pda);
rrdNodes[i].params[0].p = pda;
rrdNodes[i].params[1].p = pda->bufPtr;
rrdNodes[i].params[2].v = parityStripeID;
rrdNodes[i].params[3].v =
RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, 0, 0,
which_ru);
}
}
if (new_asm_h[1]) {
for (j = 0, pda = new_asm_h[1]->stripeMap->physInfo;
j < new_asm_h[1]->stripeMap->numStripeUnitsAccessed;
j++, pda = pda->next) {
rf_InitNode(&rrdNodes[i + j], rf_wait, RF_FALSE,
rf_DiskReadFunc, rf_DiskReadUndoFunc,
rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h,
"Rrd", allocList);
RF_ASSERT(pda);
rrdNodes[i + j].params[0].p = pda;
rrdNodes[i + j].params[1].p = pda->bufPtr;
rrdNodes[i + j].params[2].v = parityStripeID;
rrdNodes[i + j].params[3].v =
RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, 0, 0,
which_ru);
}
}
/* Make a PDA for the parity unit. */
RF_MallocAndAdd(parityPDA, sizeof(RF_PhysDiskAddr_t),
(RF_PhysDiskAddr_t *), allocList);
parityPDA->row = asmap->parityInfo->row;
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, 0, 0,
which_ru);
/*
* The last and nastiest step is to assign all
* the parameters of the Xor node.
*/
paramNum = 0;
for (i = 0; i < nRrdNodes; i++) {
/* All the Rrd nodes need to be xored together. */
xorNode->params[paramNum++] = rrdNodes[i].params[0];
xorNode->params[paramNum++] = rrdNodes[i].params[1];
}
for (i = 0; i < nRudNodes; i++) {
/* Any Rud nodes that overlap the failed access need to be
* xored in. */
if (overlappingPDAs[i]) {
RF_MallocAndAdd(pda, sizeof(RF_PhysDiskAddr_t),
(RF_PhysDiskAddr_t *), allocList);
bcopy((char *) rudNodes[i].params[0].p, (char *) pda,
sizeof(RF_PhysDiskAddr_t));
rf_RangeRestrictPDA(raidPtr, failedPDA, pda,
RF_RESTRICT_DOBUFFER, 0);
xorNode->params[paramNum++].p = pda;
xorNode->params[paramNum++].p = pda->bufPtr;
}
}
RF_Free(overlappingPDAs, asmap->numStripeUnitsAccessed * sizeof(char));
/* 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;
RF_BZERO(bp, failedPDA->bufPtr, 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;
for (i = 0; i < nRrdNodes; i++) {
RF_ASSERT(rrdNodes[i].numSuccedents == 1);
blockNode->succedents[1 + i] = &rrdNodes[i];
rrdNodes[i].antecedents[0] = blockNode;
rrdNodes[i].antType[0] = rf_control;
}
for (i = 0; i < nRudNodes; i++) {
RF_ASSERT(rudNodes[i].numSuccedents == 1);
blockNode->succedents[1 + nRrdNodes + i] = &rudNodes[i];
rudNodes[i].antecedents[0] = blockNode;
rudNodes[i].antType[0] = rf_control;
}
/* 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;
for (i = 0; i < nRrdNodes; i++) {
RF_ASSERT(rrdNodes[i].numSuccedents == 1);
rrdNodes[i].succedents[0] = xorNode;
xorNode->antecedents[1 + i] = &rrdNodes[i];
xorNode->antType[1 + i] = rf_trueData;
}
for (i = 0; i < nRudNodes; i++) {
RF_ASSERT(rudNodes[i].numSuccedents == 1);
rudNodes[i].succedents[0] = xorNode;
xorNode->antecedents[1 + nRrdNodes + i] = &rudNodes[i];
xorNode->antType[1 + nRrdNodes + i] = rf_trueData;
}
/* 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;
}
/*****************************************************************************
* 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_dagDebug) {
printf("[Creating RAID C degraded read DAG]\n");
}
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) */
RF_CallocAndAdd(nodes, 4, sizeof(RF_DagNode_t), (RF_DagNode_t *),
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, 0, 0, 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, 0, 0, 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, 0, 0, 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;
}
/*
* 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];
RF_PhysDiskAddr_t *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 unaccessed
* 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 CONS_PDA(if,start,num) do { \
pda_p->row = asmap->if->row; \
pda_p->col = asmap->if->col; \
pda_p->startSector = ((asmap->if->startSector / secPerSU) * \
secPerSU) + start; \
pda_p->numSector = num; \
pda_p->next = NULL; \
RF_MallocAndAdd(pda_p->bufPtr, \
rf_RaidAddressToByte(raidPtr,num),(char *), allocList); \
} while (0)
if (asmap->numDataFailed == 1) {
PDAPerDisk = 1;
state = 1;
RF_MallocAndAdd(*pqpdap, 2 * sizeof(RF_PhysDiskAddr_t),
(RF_PhysDiskAddr_t *), 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;
RF_MallocAndAdd(*pqpdap, 2 * sizeof(RF_PhysDiskAddr_t),
(RF_PhysDiskAddr_t *), 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. */
RF_MallocAndAdd(*pqpdap, 4 * sizeof(RF_PhysDiskAddr_t),
(RF_PhysDiskAddr_t *), 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 begining. */
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. */
RF_CallocAndAdd(pda_p, napdas, sizeof(RF_PhysDiskAddr_t),
(RF_PhysDiskAddr_t *), allocList);
*pdap = pda_p;
/* Link them 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->row), &(pda_p->col), &(pda_p->startSector), 0);
/* Skip over dead disks. */
if (RF_DEAD_DISK(raidPtr->Disks[pda_p->row][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;
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr, pda_p->numSector),
(char *), allocList);
break;
case 2: /* Full stripe. */
pda_p->numSector = secPerSU;
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr, secPerSU),
(char *), allocList);
break;
case 3: /* Two slabs. */
pda_p->numSector = fone->numSector;
pda_p->raidAddress += fone_start;
pda_p->startSector += fone_start;
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr, pda_p->numSector),
(char *), allocList);
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->row), &(pda_p->col),
&(pda_p->startSector), 0);
pda_p->numSector = ftwo->numSector;
pda_p->raidAddress += ftwo_start;
pda_p->startSector += ftwo_start;
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr, pda_p->numSector),
(char *), allocList);
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 begining.
*/
pda_p->numSector = suoff - fone_start;
pda_p->raidAddress = sosAddr + (i * secPerSU)
+ fone_start;
(raidPtr->Layout.map->MapSector) (raidPtr,
pda_p->raidAddress, &(pda_p->row),
&(pda_p->col), &(pda_p->startSector), 0);
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr,
pda_p->numSector), (char *), allocList);
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->row),
&(pda_p->col), &(pda_p->startSector), 0);
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr,
pda_p->numSector), (char *), allocList);
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->row),
&(pda_p->col), &(pda_p->startSector), 0);
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr,
pda_p->numSector), (char *), allocList);
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->row), &(pda_p->col),
&(pda_p->startSector), 0);
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr,
pda_p->numSector), (char *),
allocList);
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
* begining.
*/
pda_p->numSector = suoff - fone_start;
pda_p->raidAddress = sosAddr +
(i * secPerSU) + fone_start;
(raidPtr->Layout.map->MapSector)
(raidPtr, pda_p->raidAddress,
&(pda_p->row), &(pda_p->col),
&(pda_p->startSector), 0);
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr,
pda_p->numSector), (char *),
allocList);
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->row), &(pda_p->col),
&(pda_p->startSector), 0);
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr,
pda_p->numSector), (char *),
allocList);
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
* begining.
*/
pda_p->numSector = suoff - ftwo_start;
pda_p->raidAddress = sosAddr +
(i * secPerSU) + ftwo_start;
(raidPtr->Layout.map->MapSector)
(raidPtr, pda_p->raidAddress,
&(pda_p->row), &(pda_p->col),
&(pda_p->startSector), 0);
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr,
pda_p->numSector), (char *),
allocList);
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->row), &(pda_p->col),
&(pda_p->startSector), 0);
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr,
pda_p->numSector), (char *),
allocList);
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->row), &(pda_p->col), &(pda_p->startSector), 0);
/* Skip over dead disks. */
if (RF_DEAD_DISK(raidPtr->Disks[pda_p->row][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;
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr, pda_p->numSector),
(char *), allocList);
break;
case 2: /* Full stripe. */
pda_p->numSector = secPerSU;
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr, secPerSU),
(char *), allocList);
break;
case 3: /* Two slabs. */
pda_p->numSector = fone->numSector;
pda_p->raidAddress += fone_start;
pda_p->startSector += fone_start;
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr, pda_p->numSector),
(char *), allocList);
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->row), &(pda_p->col),
&(pda_p->startSector), 0);
pda_p->numSector = ftwo->numSector;
pda_p->raidAddress += ftwo_start;
pda_p->startSector += ftwo_start;
RF_MallocAndAdd(pda_p->bufPtr,
rf_RaidAddressToByte(raidPtr, pda_p->numSector),
(char *), allocList);
break;
default:
RF_PANIC();
}
pda_p++;
}
RF_ASSERT(pda_p - *pdap == napdas);
return;
}
#define INIT_DISK_NODE(node,name) do { \
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; \
} while (0)
#define DISK_NODE_PARAMS(_node_,_p_) do { \
(_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, \
0, 0, which_ru); \
} while (0)
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,
char *redundantReadNodeName,
char *recoveryNodeName,
int (*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_dagDebug)
printf("[Creating Double Degraded Read DAG]\n");
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;
RF_CallocAndAdd(nodes, nNodes, sizeof(RF_DagNode_t), (RF_DagNode_t *),
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 ? */
}
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