void
rf_CommonCreateSimpleDegradedWriteDAG(RF_Raid_t *raidPtr,
RF_AccessStripeMap_t *asmap,
RF_DagHeader_t *dag_h, void *bp,
RF_RaidAccessFlags_t flags,
RF_AllocListElem_t *allocList,
int nfaults,
int (*redFunc) (RF_DagNode_t *),
int allowBufferRecycle)
{
int nNodes, nRrdNodes, nWndNodes, nXorBufs, i, j, paramNum,
rdnodesFaked;
RF_DagNode_t *blockNode, *unblockNode, *wnpNode, *wnqNode, *termNode;
RF_DagNode_t *wndNodes, *rrdNodes, *xorNode, *commitNode;
RF_DagNode_t *tmpNode, *tmpwndNode, *tmprrdNode;
RF_SectorCount_t sectorsPerSU;
RF_ReconUnitNum_t which_ru;
char *xorTargetBuf = NULL; /* the target buffer for the XOR
* operation */
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;
layoutPtr = &(raidPtr->Layout);
parityStripeID = rf_RaidAddressToParityStripeID(layoutPtr, asmap->raidAddress,
&which_ru);
sectorsPerSU = layoutPtr->sectorsPerStripeUnit;
/* failedPDA points to the pda within the asm that targets the failed
* disk */
failedPDA = asmap->failedPDAs[0];
#if RF_DEBUG_DAG
if (rf_dagDebug)
printf("[Creating degraded-write DAG]\n");
#endif
RF_ASSERT(asmap->numDataFailed == 1);
dag_h->creator = "SimpleDegradedWriteDAG";
/*
* 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, NULL, overlappingPDAs, allocList);
/* create all the nodes at once */
nWndNodes = asmap->numStripeUnitsAccessed - 1; /* no access is
* generated for the
* failed pda */
nRrdNodes = ((new_asm_h[0]) ? new_asm_h[0]->stripeMap->numStripeUnitsAccessed : 0) +
((new_asm_h[1]) ? new_asm_h[1]->stripeMap->numStripeUnitsAccessed : 0);
/*
* XXX
*
* There's a bug with a complete stripe overwrite- that means 0 reads
* of old data, and the rest of the DAG generation code doesn't like
* that. A release is coming, and I don't wanna risk breaking a critical
* DAG generator, so here's what I'm gonna do- if there's no read nodes,
* I'm gonna fake there being a read node, and I'm gonna swap in a
* no-op node in its place (to make all the link-up code happy).
* This should be fixed at some point. --jimz
*/
if (nRrdNodes == 0) {
nRrdNodes = 1;
rdnodesFaked = 1;
} else {
rdnodesFaked = 0;
}
/* lock, unlock, xor, Wnd, Rrd, W(nfaults) */
nNodes = 5 + nfaults + nWndNodes + nRrdNodes;
blockNode = rf_AllocDAGNode();
blockNode->list_next = dag_h->nodes;
dag_h->nodes = blockNode;
commitNode = rf_AllocDAGNode();
commitNode->list_next = dag_h->nodes;
dag_h->nodes = commitNode;
unblockNode = rf_AllocDAGNode();
unblockNode->list_next = dag_h->nodes;
dag_h->nodes = unblockNode;
termNode = rf_AllocDAGNode();
termNode->list_next = dag_h->nodes;
dag_h->nodes = termNode;
xorNode = rf_AllocDAGNode();
xorNode->list_next = dag_h->nodes;
dag_h->nodes = xorNode;
wnpNode = rf_AllocDAGNode();
wnpNode->list_next = dag_h->nodes;
dag_h->nodes = wnpNode;
for (i = 0; i < nWndNodes; i++) {
tmpNode = rf_AllocDAGNode();
tmpNode->list_next = dag_h->nodes;
dag_h->nodes = tmpNode;
}
wndNodes = dag_h->nodes;
for (i = 0; i < nRrdNodes; i++) {
tmpNode = rf_AllocDAGNode();
tmpNode->list_next = dag_h->nodes;
dag_h->nodes = tmpNode;
}
rrdNodes = dag_h->nodes;
#if (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0)
if (nfaults == 2) {
wnqNode = rf_AllocDAGNode();
wnqNode->list_next = dag_h->nodes;
dag_h->nodes = wnqNode;
} else {
#endif
wnqNode = NULL;
#if (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0)
}
#endif
/* this dag can not commit until all rrd and xor Nodes have completed */
dag_h->numCommitNodes = 1;
dag_h->numCommits = 0;
dag_h->numSuccedents = 1;
RF_ASSERT(nRrdNodes > 0);
rf_InitNode(blockNode, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
NULL, nRrdNodes, 0, 0, 0, dag_h, "Nil", allocList);
rf_InitNode(commitNode, rf_wait, RF_TRUE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
NULL, nWndNodes + nfaults, 1, 0, 0, dag_h, "Cmt", allocList);
rf_InitNode(unblockNode, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
NULL, 1, nWndNodes + nfaults, 0, 0, dag_h, "Nil", 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, redFunc, rf_NullNodeUndoFunc, NULL, 1,
nRrdNodes, 2 * nXorBufs + 2, nfaults, dag_h, "Xrc", allocList);
/*
* Fill in the Rrd nodes. If any of the rrd buffers are the same size as
* the failed buffer, save a pointer to it so we can use it as the target
* of the XOR. The pdas in the rrd nodes have been range-restricted, so if
* a buffer is the same size as the failed buffer, it must also be at the
* same alignment within the SU.
*/
i = 0;
tmprrdNode = rrdNodes;
if (new_asm_h[0]) {
for (i = 0, 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;
}
}
/* i now equals the number of stripe units accessed in new_asm_h[0] */
/* Note that for tmprrdNode, this means a continuation from above, so no need to
assign it anything.. */
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(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);
if (allowBufferRecycle && (pda->numSector == failedPDA->numSector))
xorTargetBuf = pda->bufPtr;
tmprrdNode = tmprrdNode->list_next;
}
}
if (rdnodesFaked) {
/*
* This is where we'll init that fake noop read node
* (XXX should the wakeup func be different?)
*/
/* node that rrdNodes will just be a single node... */
rf_InitNode(rrdNodes, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc,
NULL, 1, 1, 0, 0, dag_h, "RrN", allocList);
}
/*
* Make a PDA for the parity unit. The parity PDA should start at
* the same offset into the SU as the failed PDA.
*/
/* Danner comment: I don't think this copy is really necessary. We are
* in one of two cases here. (1) The entire failed unit is written.
* Then asmap->parityInfo will describe the entire parity. (2) We are
* only writing a subset of the failed unit and nothing else. Then the
* asmap->parityInfo describes the failed unit and the copy can also
* be avoided. */
parityPDA = rf_AllocPhysDiskAddr();
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;
if (!xorTargetBuf) {
xorTargetBuf = rf_AllocBuffer(raidPtr, dag_h, rf_RaidAddressToByte(raidPtr, failedPDA->numSector));
}
/* init the Wnp node */
rf_InitNode(wnpNode, rf_wait, RF_FALSE, rf_DiskWriteFunc, rf_DiskWriteUndoFunc,
rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, "Wnp", allocList);
wnpNode->params[0].p = parityPDA;
wnpNode->params[1].p = xorTargetBuf;
wnpNode->params[2].v = parityStripeID;
wnpNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
#if (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0)
/* fill in the Wnq Node */
if (nfaults == 2) {
{
RF_MallocAndAdd(parityPDA, sizeof(RF_PhysDiskAddr_t),
(RF_PhysDiskAddr_t *), allocList);
parityPDA->col = asmap->qInfo->col;
parityPDA->startSector = ((asmap->qInfo->startSector / sectorsPerSU)
* sectorsPerSU) + (failedPDA->startSector % sectorsPerSU);
parityPDA->numSector = failedPDA->numSector;
rf_InitNode(wnqNode, rf_wait, RF_FALSE, rf_DiskWriteFunc, rf_DiskWriteUndoFunc,
rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, "Wnq", allocList);
wnqNode->params[0].p = parityPDA;
RF_MallocAndAdd(xorNode->results[1],
rf_RaidAddressToByte(raidPtr, failedPDA->numSector), (char *), allocList);
wnqNode->params[1].p = xorNode->results[1];
wnqNode->params[2].v = parityStripeID;
wnqNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
}
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) */
RF_MallocAndAdd(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, 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;
}
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();
blockNode->list_next = dag_h->nodes;
dag_h->nodes = blockNode;
commitNode = rf_AllocDAGNode();
commitNode->list_next = dag_h->nodes;
dag_h->nodes = commitNode;
xorNode = rf_AllocDAGNode();
xorNode->list_next = dag_h->nodes;
dag_h->nodes = xorNode;
rpNode = rf_AllocDAGNode();
rpNode->list_next = dag_h->nodes;
dag_h->nodes = rpNode;
termNode = rf_AllocDAGNode();
termNode->list_next = dag_h->nodes;
dag_h->nodes = termNode;
for (i = 0; i < nRudNodes; i++) {
tmpNode = rf_AllocDAGNode();
tmpNode->list_next = dag_h->nodes;
dag_h->nodes = tmpNode;
}
rudNodes = dag_h->nodes;
for (i = 0; i < nRrdNodes; i++) {
tmpNode = rf_AllocDAGNode();
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();
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();
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;
}
void
rf_CommonCreateLargeWriteDAG(RF_Raid_t *raidPtr, RF_AccessStripeMap_t *asmap,
RF_DagHeader_t *dag_h, void *bp,
RF_RaidAccessFlags_t flags,
RF_AllocListElem_t *allocList,
int nfaults, int (*redFunc) (RF_DagNode_t *),
int allowBufferRecycle)
{
RF_DagNode_t *wndNodes, *rodNodes, *xorNode, *wnpNode, *tmpNode;
RF_DagNode_t *blockNode, *commitNode, *termNode;
#if (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0)
RF_DagNode_t *wnqNode;
#endif
int nWndNodes, nRodNodes, i, nodeNum, asmNum;
RF_AccessStripeMapHeader_t *new_asm_h[2];
RF_StripeNum_t parityStripeID;
char *sosBuffer, *eosBuffer;
RF_ReconUnitNum_t which_ru;
RF_RaidLayout_t *layoutPtr;
RF_PhysDiskAddr_t *pda;
layoutPtr = &(raidPtr->Layout);
parityStripeID = rf_RaidAddressToParityStripeID(layoutPtr,
asmap->raidAddress,
&which_ru);
#if RF_DEBUG_DAG
if (rf_dagDebug) {
printf("[Creating large-write DAG]\n");
}
#endif
dag_h->creator = "LargeWriteDAG";
dag_h->numCommitNodes = 1;
dag_h->numCommits = 0;
dag_h->numSuccedents = 1;
/* alloc the nodes: Wnd, xor, commit, block, term, and Wnp */
nWndNodes = asmap->numStripeUnitsAccessed;
for (i = 0; i < nWndNodes; i++) {
tmpNode = rf_AllocDAGNode();
tmpNode->list_next = dag_h->nodes;
dag_h->nodes = tmpNode;
}
wndNodes = dag_h->nodes;
xorNode = rf_AllocDAGNode();
xorNode->list_next = dag_h->nodes;
dag_h->nodes = xorNode;
wnpNode = rf_AllocDAGNode();
wnpNode->list_next = dag_h->nodes;
dag_h->nodes = wnpNode;
blockNode = rf_AllocDAGNode();
blockNode->list_next = dag_h->nodes;
dag_h->nodes = blockNode;
commitNode = rf_AllocDAGNode();
commitNode->list_next = dag_h->nodes;
dag_h->nodes = commitNode;
termNode = rf_AllocDAGNode();
termNode->list_next = dag_h->nodes;
dag_h->nodes = termNode;
#if (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0)
if (nfaults == 2) {
wnqNode = rf_AllocDAGNode();
} else {
wnqNode = NULL;
}
#endif
rf_MapUnaccessedPortionOfStripe(raidPtr, layoutPtr, asmap, dag_h,
new_asm_h, &nRodNodes, &sosBuffer,
&eosBuffer, allocList);
if (nRodNodes > 0) {
for (i = 0; i < nRodNodes; i++) {
tmpNode = rf_AllocDAGNode();
tmpNode->list_next = dag_h->nodes;
dag_h->nodes = tmpNode;
}
rodNodes = dag_h->nodes;
} else {
rodNodes = NULL;
}
/* begin node initialization */
if (nRodNodes > 0) {
rf_InitNode(blockNode, rf_wait, RF_FALSE, rf_NullNodeFunc,
rf_NullNodeUndoFunc, NULL, nRodNodes, 0, 0, 0,
dag_h, "Nil", allocList);
} else {
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, nWndNodes + nfaults, 1, 0, 0,
dag_h, "Cmt", allocList);
rf_InitNode(termNode, rf_wait, RF_FALSE, rf_TerminateFunc,
rf_TerminateUndoFunc, NULL, 0, nWndNodes + nfaults, 0, 0,
dag_h, "Trm", allocList);
/* initialize the Rod nodes */
tmpNode = rodNodes;
for (nodeNum = asmNum = 0; asmNum < 2; asmNum++) {
if (new_asm_h[asmNum]) {
pda = new_asm_h[asmNum]->stripeMap->physInfo;
while (pda) {
rf_InitNode(tmpNode, rf_wait,
RF_FALSE, rf_DiskReadFunc,
rf_DiskReadUndoFunc,
rf_GenericWakeupFunc,
1, 1, 4, 0, dag_h,
"Rod", allocList);
tmpNode->params[0].p = pda;
tmpNode->params[1].p = pda->bufPtr;
tmpNode->params[2].v = parityStripeID;
tmpNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY,
which_ru);
nodeNum++;
pda = pda->next;
tmpNode = tmpNode->list_next;
}
}
}
RF_ASSERT(nodeNum == nRodNodes);
/* initialize the wnd nodes */
pda = asmap->physInfo;
tmpNode = wndNodes;
for (i = 0; i < nWndNodes; i++) {
rf_InitNode(tmpNode, rf_wait, RF_FALSE,
rf_DiskWriteFunc, rf_DiskWriteUndoFunc,
rf_GenericWakeupFunc, 1, 1, 4, 0,
dag_h, "Wnd", allocList);
RF_ASSERT(pda != NULL);
tmpNode->params[0].p = pda;
tmpNode->params[1].p = pda->bufPtr;
tmpNode->params[2].v = parityStripeID;
tmpNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
pda = pda->next;
tmpNode = tmpNode->list_next;
}
/* initialize the redundancy node */
if (nRodNodes > 0) {
rf_InitNode(xorNode, rf_wait, RF_FALSE, redFunc,
rf_NullNodeUndoFunc, NULL, 1,
nRodNodes, 2 * (nWndNodes + nRodNodes) + 1,
nfaults, dag_h, "Xr ", allocList);
} else {
rf_InitNode(xorNode, rf_wait, RF_FALSE, redFunc,
rf_NullNodeUndoFunc, NULL, 1,
1, 2 * (nWndNodes + nRodNodes) + 1,
nfaults, dag_h, "Xr ", allocList);
}
xorNode->flags |= RF_DAGNODE_FLAG_YIELD;
tmpNode = wndNodes;
for (i = 0; i < nWndNodes; i++) {
/* pda */
xorNode->params[2 * i + 0] = tmpNode->params[0];
/* buf ptr */
xorNode->params[2 * i + 1] = tmpNode->params[1];
tmpNode = tmpNode->list_next;
}
tmpNode = rodNodes;
for (i = 0; i < nRodNodes; i++) {
/* pda */
xorNode->params[2 * (nWndNodes + i) + 0] = tmpNode->params[0];
/* buf ptr */
xorNode->params[2 * (nWndNodes + i) + 1] = tmpNode->params[1];
tmpNode = tmpNode->list_next;
}
/* xor node needs to get at RAID information */
xorNode->params[2 * (nWndNodes + nRodNodes)].p = raidPtr;
/*
* Look for an Rod node that reads a complete SU. If none,
* alloc a buffer to receive the parity info. Note that we
* can't use a new data buffer because it will not have gotten
* written when the xor occurs. */
if (allowBufferRecycle) {
tmpNode = rodNodes;
for (i = 0; i < nRodNodes; i++) {
if (((RF_PhysDiskAddr_t *) tmpNode->params[0].p)->numSector == raidPtr->Layout.sectorsPerStripeUnit)
break;
tmpNode = tmpNode->list_next;
}
}
if ((!allowBufferRecycle) || (i == nRodNodes)) {
xorNode->results[0] = rf_AllocBuffer(raidPtr, dag_h, rf_RaidAddressToByte(raidPtr, raidPtr->Layout.sectorsPerStripeUnit));
} else {
/* this works because the only way we get here is if
allowBufferRecycle is true and we went through the
above for loop, and exited via the break before
i==nRodNodes was true. That means tmpNode will
still point to a valid node -- the one we want for
here! */
xorNode->results[0] = tmpNode->params[1].p;
}
/* initialize the Wnp node */
rf_InitNode(wnpNode, rf_wait, RF_FALSE, rf_DiskWriteFunc,
rf_DiskWriteUndoFunc, rf_GenericWakeupFunc, 1, 1, 4, 0,
dag_h, "Wnp", allocList);
wnpNode->params[0].p = asmap->parityInfo;
wnpNode->params[1].p = xorNode->results[0];
wnpNode->params[2].v = parityStripeID;
wnpNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
/* parityInfo must describe entire parity unit */
RF_ASSERT(asmap->parityInfo->next == NULL);
#if (RF_INCLUDE_DECL_PQ > 0) || (RF_INCLUDE_RAID6 > 0)
if (nfaults == 2) {
/*
* We never try to recycle a buffer for the Q calcuation
* in addition to the parity. This would cause two buffers
* to get smashed during the P and Q calculation, guaranteeing
* one would be wrong.
*/
RF_MallocAndAdd(xorNode->results[1],
rf_RaidAddressToByte(raidPtr, raidPtr->Layout.sectorsPerStripeUnit),
(void *), allocList);
rf_InitNode(wnqNode, rf_wait, RF_FALSE, rf_DiskWriteFunc,
rf_DiskWriteUndoFunc, rf_GenericWakeupFunc,
1, 1, 4, 0, dag_h, "Wnq", allocList);
wnqNode->params[0].p = asmap->qInfo;
wnqNode->params[1].p = xorNode->results[1];
wnqNode->params[2].v = parityStripeID;
wnqNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, which_ru);
/* parityInfo must describe entire parity unit */
RF_ASSERT(asmap->parityInfo->next == NULL);
}
void
rf_CreateMirrorReadDAG(
RF_Raid_t *raidPtr,
RF_AccessStripeMap_t *asmap,
RF_DagHeader_t *dag_h,
void *bp,
RF_RaidAccessFlags_t flags,
RF_AllocListElem_t *allocList,
int (*readfunc) (RF_DagNode_t *)
)
{
RF_DagNode_t *readNodes, *nodes, *blockNode, *commitNode, *termNode;
RF_PhysDiskAddr_t *data_pda = asmap->physInfo;
RF_PhysDiskAddr_t *parity_pda = asmap->parityInfo;
int i, n, totalNumNodes;
n = asmap->numStripeUnitsAccessed;
dag_h->creator = "RaidOneReadDAG";
if (rf_dagDebug) {
printf("[Creating RAID level 1 read DAG]\n");
}
/*
* This dag can not commit until the commit node is reached.
* Errors prior to the commit point imply the dag has failed.
*/
dag_h->numCommitNodes = 1;
dag_h->numCommits = 0;
dag_h->numSuccedents = 1;
/*
* Node count:
* n data reads
* 1 block node
* 1 commit node
* 1 terminator node
*/
RF_ASSERT(n > 0);
totalNumNodes = n + 3;
RF_CallocAndAdd(nodes, totalNumNodes, sizeof(RF_DagNode_t),
(RF_DagNode_t *), allocList);
i = 0;
readNodes = &nodes[i];
i += n;
blockNode = &nodes[i];
i += 1;
commitNode = &nodes[i];
i += 1;
termNode = &nodes[i];
i += 1;
RF_ASSERT(i == totalNumNodes);
/* Initialize nodes. */
rf_InitNode(blockNode, rf_wait, RF_FALSE, rf_NullNodeFunc,
rf_NullNodeUndoFunc, NULL, n, 0, 0, 0, dag_h, "Nil", allocList);
rf_InitNode(commitNode, rf_wait, RF_TRUE, rf_NullNodeFunc,
rf_NullNodeUndoFunc, NULL, 1, n, 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);
for (i = 0; i < n; i++) {
RF_ASSERT(data_pda != NULL);
RF_ASSERT(parity_pda != NULL);
rf_InitNode(&readNodes[i], rf_wait, RF_FALSE, readfunc,
rf_DiskReadMirrorUndoFunc, rf_GenericWakeupFunc, 1, 1, 5,
0, dag_h, "Rmir", allocList);
readNodes[i].params[0].p = data_pda;
readNodes[i].params[1].p = data_pda->bufPtr;
/* Parity stripe id is not necessary. */
readNodes[i].params[2].p = 0;
readNodes[i].params[3].v =
RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, 0, 0, 0);
readNodes[i].params[4].p = parity_pda;
data_pda = data_pda->next;
parity_pda = parity_pda->next;
}
/*
* Connect nodes.
*/
/* Connect hdr to block node. */
RF_ASSERT(blockNode->numAntecedents == 0);
dag_h->succedents[0] = blockNode;
/* Connect block node to read nodes. */
RF_ASSERT(blockNode->numSuccedents == n);
for (i = 0; i < n; i++) {
RF_ASSERT(readNodes[i].numAntecedents == 1);
blockNode->succedents[i] = &readNodes[i];
readNodes[i].antecedents[0] = blockNode;
readNodes[i].antType[0] = rf_control;
}
/* Connect read nodes to commit node. */
RF_ASSERT(commitNode->numAntecedents == n);
for (i = 0; i < n; i++) {
RF_ASSERT(readNodes[i].numSuccedents == 1);
readNodes[i].succedents[0] = commitNode;
commitNode->antecedents[i] = &readNodes[i];
commitNode->antType[i] = rf_control;
}
/* Connect commit node to term node. */
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;
}
void
rf_CreateNonredundantDAG(
RF_Raid_t *raidPtr,
RF_AccessStripeMap_t *asmap,
RF_DagHeader_t *dag_h,
void *bp,
RF_RaidAccessFlags_t flags,
RF_AllocListElem_t *allocList,
RF_IoType_t type
)
{
RF_DagNode_t *nodes, *diskNodes, *blockNode, *commitNode, *termNode;
RF_PhysDiskAddr_t *pda = asmap->physInfo;
int (*doFunc) (RF_DagNode_t *), (*undoFunc) (RF_DagNode_t *);
int i, n, totalNumNodes;
char *name;
n = asmap->numStripeUnitsAccessed;
dag_h->creator = "NonredundantDAG";
RF_ASSERT(RF_IO_IS_R_OR_W(type));
switch (type) {
case RF_IO_TYPE_READ:
doFunc = rf_DiskReadFunc;
undoFunc = rf_DiskReadUndoFunc;
name = "R ";
if (rf_dagDebug)
printf("[Creating non-redundant read DAG]\n");
break;
case RF_IO_TYPE_WRITE:
doFunc = rf_DiskWriteFunc;
undoFunc = rf_DiskWriteUndoFunc;
name = "W ";
if (rf_dagDebug)
printf("[Creating non-redundant write DAG]\n");
break;
default:
RF_PANIC();
}
/*
* For reads, the dag can not commit until the block node is reached.
* For writes, the dag commits immediately.
*/
dag_h->numCommitNodes = 1;
dag_h->numCommits = 0;
dag_h->numSuccedents = 1;
/*
* Node count:
* 1 block node
* n data reads (or writes)
* 1 commit node
* 1 terminator node
*/
RF_ASSERT(n > 0);
totalNumNodes = n + 3;
RF_CallocAndAdd(nodes, totalNumNodes, sizeof(RF_DagNode_t),
(RF_DagNode_t *), allocList);
i = 0;
diskNodes = &nodes[i];
i += n;
blockNode = &nodes[i];
i += 1;
commitNode = &nodes[i];
i += 1;
termNode = &nodes[i];
i += 1;
RF_ASSERT(i == totalNumNodes);
/* Initialize nodes. */
switch (type) {
case RF_IO_TYPE_READ:
rf_InitNode(blockNode, rf_wait, RF_FALSE, rf_NullNodeFunc,
rf_NullNodeUndoFunc, NULL, n, 0, 0, 0, dag_h, "Nil",
allocList);
rf_InitNode(commitNode, rf_wait, RF_TRUE, rf_NullNodeFunc,
rf_NullNodeUndoFunc, NULL, 1, n, 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);
break;
case RF_IO_TYPE_WRITE:
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, n, 1, 0, 0, dag_h, "Cmt",
allocList);
rf_InitNode(termNode, rf_wait, RF_FALSE, rf_TerminateFunc,
rf_TerminateUndoFunc, NULL, 0, n, 0, 0, dag_h, "Trm",
allocList);
break;
default:
RF_PANIC();
}
for (i = 0; i < n; i++) {
RF_ASSERT(pda != NULL);
rf_InitNode(&diskNodes[i], rf_wait, RF_FALSE, doFunc, undoFunc,
rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, name, allocList);
diskNodes[i].params[0].p = pda;
diskNodes[i].params[1].p = pda->bufPtr;
/* Parity stripe id is not necessary. */
diskNodes[i].params[2].v = 0;
diskNodes[i].params[3].v =
RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, 0, 0, 0);
pda = pda->next;
}
/*
* Connect nodes.
*/
/* Connect hdr to block node. */
RF_ASSERT(blockNode->numAntecedents == 0);
dag_h->succedents[0] = blockNode;
if (type == RF_IO_TYPE_READ) {
/* Connecting a nonredundant read DAG. */
RF_ASSERT(blockNode->numSuccedents == n);
RF_ASSERT(commitNode->numAntecedents == n);
for (i = 0; i < n; i++) {
/* Connect block node to each read node. */
RF_ASSERT(diskNodes[i].numAntecedents == 1);
blockNode->succedents[i] = &diskNodes[i];
diskNodes[i].antecedents[0] = blockNode;
diskNodes[i].antType[0] = rf_control;
/* Connect each read node to the commit node. */
RF_ASSERT(diskNodes[i].numSuccedents == 1);
diskNodes[i].succedents[0] = commitNode;
commitNode->antecedents[i] = &diskNodes[i];
commitNode->antType[i] = rf_control;
}
/* Connect the commit node to the term node. */
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;
} else {
/* Connecting a nonredundant write DAG. */
/* Connect the block node to the commit node. */
RF_ASSERT(blockNode->numSuccedents == 1);
RF_ASSERT(commitNode->numAntecedents == 1);
blockNode->succedents[0] = commitNode;
commitNode->antecedents[0] = blockNode;
commitNode->antType[0] = rf_control;
RF_ASSERT(commitNode->numSuccedents == n);
RF_ASSERT(termNode->numAntecedents == n);
RF_ASSERT(termNode->numSuccedents == 0);
for (i = 0; i < n; i++) {
/* Connect the commit node to each write node. */
RF_ASSERT(diskNodes[i].numAntecedents == 1);
commitNode->succedents[i] = &diskNodes[i];
diskNodes[i].antecedents[0] = commitNode;
diskNodes[i].antType[0] = rf_control;
/* Connect each write node to the term node. */
RF_ASSERT(diskNodes[i].numSuccedents == 1);
diskNodes[i].succedents[0] = termNode;
termNode->antecedents[i] = &diskNodes[i];
termNode->antType[i] = rf_control;
}
}
}