NetBSD/sys/dev/raidframe/rf_dagdegwr.c

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/* $NetBSD: rf_dagdegwr.c,v 1.1 1998/11/13 04:20:27 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_dagdegwr.c
*
* code for creating degraded write DAGs
*
* :
* Log: rf_dagdegwr.c,v
* Revision 1.23 1996/11/05 21:10:40 jimz
* failed pda generalization
*
* Revision 1.22 1996/08/23 14:49:48 jimz
* remove bogus assert from small write double deg DAG generator
*
* Revision 1.21 1996/08/21 05:09:44 jimz
* get rid of bogus fakery in DoubleDegSmallWrite
*
* Revision 1.20 1996/08/21 04:14:35 jimz
* cleanup doubledegsmallwrite
* NOTE: we need doubledeglargewrite
*
* Revision 1.19 1996/08/19 21:39:38 jimz
* CommonCreateSimpleDegradedWriteDAG() was unable to correctly create DAGs for
* complete stripe overwrite accesses- it assumed the necessity to read old
* data. Rather than do the "right" thing, and risk breaking a critical DAG so
* close to release, I made a no-op read node to stick in and link up in this
* case. Seems to work.
*
* Revision 1.18 1996/07/31 15:35:34 jimz
* evenodd changes; bugfixes for double-degraded archs, generalize
* some formerly PQ-only functions
*
* Revision 1.17 1996/07/28 20:31:39 jimz
* i386netbsd port
* true/false fixup
*
* Revision 1.16 1996/07/27 23:36:08 jimz
* Solaris port of simulator
*
* Revision 1.15 1996/07/27 16:30:19 jimz
* cleanup sweep
*
* Revision 1.14 1996/07/22 19:52:16 jimz
* switched node params to RF_DagParam_t, a union of
* a 64-bit int and a void *, for better portability
* attempted hpux port, but failed partway through for
* lack of a single C compiler capable of compiling all
* source files
*
* Revision 1.13 1996/06/09 02:36:46 jimz
* lots of little crufty cleanup- fixup whitespace
* issues, comment #ifdefs, improve typing in some
* places (esp size-related)
*
* Revision 1.12 1996/06/07 22:26:27 jimz
* type-ify which_ru (RF_ReconUnitNum_t)
*
* Revision 1.11 1996/06/07 21:33:04 jimz
* begin using consistent types for sector numbers,
* stripe numbers, row+col numbers, recon unit numbers
*
* Revision 1.10 1996/05/31 22:26:54 jimz
* fix a lot of mapping problems, memory allocation problems
* found some weird lock issues, fixed 'em
* more code cleanup
*
* Revision 1.9 1996/05/30 11:29:41 jimz
* Numerous bug fixes. Stripe lock release code disagreed with the taking code
* about when stripes should be locked (I made it consistent: no parity, no lock)
* There was a lot of extra serialization of I/Os which I've removed- a lot of
* it was to calculate values for the cache code, which is no longer with us.
* More types, function, macro cleanup. Added code to properly quiesce the array
* on shutdown. Made a lot of stuff array-specific which was (bogusly) general
* before. Fixed memory allocation, freeing bugs.
*
* Revision 1.8 1996/05/27 18:56:37 jimz
* more code cleanup
* better typing
* compiles in all 3 environments
*
* Revision 1.7 1996/05/24 22:17:04 jimz
* continue code + namespace cleanup
* typed a bunch of flags
*
* Revision 1.6 1996/05/24 04:28:55 jimz
* release cleanup ckpt
*
* Revision 1.5 1996/05/23 21:46:35 jimz
* checkpoint in code cleanup (release prep)
* lots of types, function names have been fixed
*
* Revision 1.4 1996/05/23 00:33:23 jimz
* code cleanup: move all debug decls to rf_options.c, all extern
* debug decls to rf_options.h, all debug vars preceded by rf_
*
* Revision 1.3 1996/05/18 19:51:34 jimz
* major code cleanup- fix syntax, make some types consistent,
* add prototypes, clean out dead code, et cetera
*
* Revision 1.2 1996/05/08 21:01:24 jimz
* fixed up enum type names that were conflicting with other
* enums and function names (ie, "panic")
* future naming trends will be towards RF_ and rf_ for
* everything raidframe-related
*
* Revision 1.1 1996/05/03 19:21:50 wvcii
* Initial revision
*
*/
#include "rf_types.h"
#include "rf_raid.h"
#include "rf_dag.h"
#include "rf_dagutils.h"
#include "rf_dagfuncs.h"
#include "rf_threadid.h"
#include "rf_debugMem.h"
#include "rf_memchunk.h"
#include "rf_general.h"
#include "rf_dagdegwr.h"
#include "rf_sys.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.
*/
static RF_CREATE_DAG_FUNC_DECL(rf_CreateSimpleDegradedWriteDAG)
{
rf_CommonCreateSimpleDegradedWriteDAG(raidPtr, asmap, dag_h, bp,
flags, allocList,1, rf_RecoveryXorFunc, RF_TRUE);
}
void rf_CreateDegradedWriteDAG(raidPtr, asmap, dag_h, bp, flags, allocList)
RF_Raid_t *raidPtr;
RF_AccessStripeMap_t *asmap;
RF_DagHeader_t *dag_h;
void *bp;
RF_RaidAccessFlags_t flags;
RF_AllocListElem_t *allocList;
{
RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout);
RF_PhysDiskAddr_t *failedPDA = asmap->failedPDAs[0];
RF_ASSERT( asmap->numDataFailed == 1 );
dag_h->creator = "DegradedWriteDAG";
/* if the access writes only a portion of the failed unit, and also writes
* some portion of at least one surviving unit, we create two DAGs, one for
* the failed component and one for the non-failed component, and do them
* sequentially. Note that the fact that we're accessing only a portion of
* the failed unit indicates that the access either starts or ends in the
* failed unit, and hence we need create only two dags. This is inefficient
* in that the same data or parity can get read and written twice using this
* structure. I need to fix this to do the access all at once.
*/
RF_ASSERT(!(asmap->numStripeUnitsAccessed != 1 && failedPDA->numSector != layoutPtr->sectorsPerStripeUnit));
rf_CreateSimpleDegradedWriteDAG(raidPtr, asmap, dag_h, bp, flags, allocList);
}
/******************************************************************************
*
* DAG creation code begins here
*/
/******************************************************************************
*
* CommonCreateSimpleDegradedWriteDAG -- creates a DAG to do a degraded-mode
* write, which is as follows
*
* / {Wnq} --\
* hdr -> blockNode -> Rod -> Xor -> Cmt -> Wnp ----> unblock -> term
* \ {Rod} / \ Wnd ---/
* \ {Wnd} -/
*
* commit nodes: Xor, Wnd
*
* IMPORTANT:
* This DAG generator does not work for double-degraded archs since it does not
* generate Q
*
* This dag is essentially identical to the large-write dag, except that the
* write to the failed data unit is suppressed.
*
* IMPORTANT: this dag does not work in the case where the access writes only
* a portion of the failed unit, and also writes some portion of at least one
* surviving SU. this case is handled in CreateDegradedWriteDAG above.
*
* The block & unblock nodes are leftovers from a previous version. They
* do nothing, but I haven't deleted them because it would be a tremendous
* effort to put them back in.
*
* This dag is used whenever a one of the data units in a write has failed.
* If it is the parity unit that failed, the nonredundant write dag (below)
* is used.
*****************************************************************************/
void rf_CommonCreateSimpleDegradedWriteDAG(raidPtr, asmap, dag_h, bp, flags,
allocList, nfaults, redFunc, allowBufferRecycle)
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 *nodes, *wndNodes, *rrdNodes, *xorNode, *commitNode;
RF_SectorCount_t sectorsPerSU;
RF_ReconUnitNum_t which_ru;
char *xorTargetBuf = NULL; /* the target buffer for the XOR operation */
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;
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_dagDebug)
printf("[Creating degraded-write DAG]\n");
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 */
RF_Calloc(overlappingPDAs, asmap->numStripeUnitsAccessed, sizeof(char), (char *));
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;
RF_CallocAndAdd(nodes, nNodes, sizeof(RF_DagNode_t),
(RF_DagNode_t *), allocList);
i = 0;
blockNode = &nodes[i]; i += 1;
commitNode = &nodes[i]; i += 1;
unblockNode = &nodes[i]; i += 1;
termNode = &nodes[i]; i += 1;
xorNode = &nodes[i]; i += 1;
wnpNode = &nodes[i]; i += 1;
wndNodes = &nodes[i]; i += nWndNodes;
rrdNodes = &nodes[i]; i += nRrdNodes;
if (nfaults == 2) {
wnqNode = &nodes[i]; i += 1;
}
else {
wnqNode = NULL;
}
RF_ASSERT(i == nNodes);
/* 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;
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(&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);
}
}
/* i now equals the number of stripe units accessed in new_asm_h[0] */
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);
if (allowBufferRecycle && (pda->numSector == failedPDA->numSector))
xorTargetBuf = pda->bufPtr;
}
}
if (rdnodesFaked) {
/*
* This is where we'll init that fake noop read node
* (XXX should the wakeup func be different?)
*/
rf_InitNode(&rrdNodes[0], 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.
*/
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;
if (!xorTargetBuf) {
RF_CallocAndAdd(xorTargetBuf, 1,
rf_RaidAddressToByte(raidPtr, failedPDA->numSector), (char *), allocList);
}
/* 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, 0, 0, which_ru);
/* fill in the Wnq Node */
if (nfaults == 2) {
{
RF_MallocAndAdd(parityPDA, sizeof(RF_PhysDiskAddr_t),
(RF_PhysDiskAddr_t *), allocList);
parityPDA->row = asmap->qInfo->row;
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_CallocAndAdd(xorNode->results[1], 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, 0, 0, which_ru);
}
}
/* fill in the Wnd nodes */
for (pda=asmap->physInfo, i=0; i<nWndNodes; i++, pda=pda->next) {
if (pda == failedPDA) {
i--;
continue;
}
rf_InitNode(&wndNodes[i], rf_wait, RF_FALSE, rf_DiskWriteFunc, rf_DiskWriteUndoFunc,
rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, "Wnd", allocList);
RF_ASSERT(pda);
wndNodes[i].params[0].p = pda;
wndNodes[i].params[1].p = pda->bufPtr;
wndNodes[i].params[2].v = parityStripeID;
wndNodes[i].params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, 0, 0, which_ru);
}
/* fill in the results of the xor node */
xorNode->results[0] = xorTargetBuf;
/* fill in the params of the xor node */
paramNum=0;
if (rdnodesFaked == 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 < nWndNodes; i++) {
/* any Wnd 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 *)wndNodes[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 the failed PDA into the xor param list so that the
* new data gets xor'd in.
*/
xorNode->params[paramNum++].p = failedPDA;
xorNode->params[paramNum++].p = failedPDA->bufPtr;
/*
* The last 2 params to the recovery xor node are always the failed
* PDA and the raidPtr. install the failedPDA even though we have just
* done so above. This allows us to use the same XOR function for both
* degraded reads and degraded writes.
*/
xorNode->params[paramNum++].p = failedPDA;
xorNode->params[paramNum++].p = raidPtr;
RF_ASSERT( paramNum == 2*nXorBufs+2 );
/*
* Code to link nodes begins here
*/
/* link header to block node */
RF_ASSERT(blockNode->numAntecedents == 0);
dag_h->succedents[0] = blockNode;
/* link block node to rd nodes */
RF_ASSERT(blockNode->numSuccedents == nRrdNodes);
for (i = 0; i < nRrdNodes; i++) {
RF_ASSERT(rrdNodes[i].numAntecedents == 1);
blockNode->succedents[i] = &rrdNodes[i];
rrdNodes[i].antecedents[0] = blockNode;
rrdNodes[i].antType[0] = rf_control;
}
/* link read nodes to xor node*/
RF_ASSERT(xorNode->numAntecedents == nRrdNodes);
for (i = 0; i < nRrdNodes; i++) {
RF_ASSERT(rrdNodes[i].numSuccedents == 1);
rrdNodes[i].succedents[0] = xorNode;
xorNode->antecedents[i] = &rrdNodes[i];
xorNode->antType[i] = rf_trueData;
}
/* link xor node to 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;
/* link commit node to wnd nodes */
RF_ASSERT(commitNode->numSuccedents == nfaults + nWndNodes);
for (i = 0; i < nWndNodes; i++) {
RF_ASSERT(wndNodes[i].numAntecedents == 1);
commitNode->succedents[i] = &wndNodes[i];
wndNodes[i].antecedents[0] = commitNode;
wndNodes[i].antType[0] = rf_control;
}
/* link the commit node to wnp, wnq nodes */
RF_ASSERT(wnpNode->numAntecedents == 1);
commitNode->succedents[nWndNodes] = wnpNode;
wnpNode->antecedents[0] = commitNode;
wnpNode->antType[0] = rf_control;
if (nfaults == 2) {
RF_ASSERT(wnqNode->numAntecedents == 1);
commitNode->succedents[nWndNodes + 1] = wnqNode;
wnqNode->antecedents[0] = commitNode;
wnqNode->antType[0] = rf_control;
}
/* link write new data nodes to unblock node */
RF_ASSERT(unblockNode->numAntecedents == (nWndNodes + nfaults));
for(i = 0; i < nWndNodes; i++) {
RF_ASSERT(wndNodes[i].numSuccedents == 1);
wndNodes[i].succedents[0] = unblockNode;
unblockNode->antecedents[i] = &wndNodes[i];
unblockNode->antType[i] = rf_control;
}
/* link write new parity node to unblock node */
RF_ASSERT(wnpNode->numSuccedents == 1);
wnpNode->succedents[0] = unblockNode;
unblockNode->antecedents[nWndNodes] = wnpNode;
unblockNode->antType[nWndNodes] = rf_control;
/* link write new q node to unblock node */
if (nfaults == 2) {
RF_ASSERT(wnqNode->numSuccedents == 1);
wnqNode->succedents[0] = unblockNode;
unblockNode->antecedents[nWndNodes+1] = wnqNode;
unblockNode->antType[nWndNodes+1] = rf_control;
}
/* link unblock node to term node */
RF_ASSERT(unblockNode->numSuccedents == 1);
RF_ASSERT(termNode->numAntecedents == 1);
RF_ASSERT(termNode->numSuccedents == 0);
unblockNode->succedents[0] = termNode;
termNode->antecedents[0] = unblockNode;
termNode->antType[0] = rf_control;
}
#define CONS_PDA(if,start,num) \
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)
void rf_WriteGenerateFailedAccessASMs(
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;
unsigned napdas;
RF_SectorNum_t fone_start, fone_end, ftwo_start = 0, ftwo_end;
RF_PhysDiskAddr_t *fone = asmap->failedPDAs[0], *ftwo = asmap->failedPDAs[1];
RF_PhysDiskAddr_t *pda_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 wether they overlap. */
fone_start = rf_StripeUnitOffset(layoutPtr,fone->startSector);
fone_end = fone_start + fone->numSector;
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 - 2);
*nPQNodep = PDAPerDisk;
*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;
/* linkem together */
for (i=0; i < (napdas-1); i++)
pda_p[i].next = pda_p+(i+1);
sosAddr = rf_RaidAddressOfPrevStripeBoundary(layoutPtr, asmap->raidAddress);
for (i=0; 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 DISK_NODE_PDA(node) ((node)->params[0].p)
#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, 0, 0, which_ru)
void rf_DoubleDegSmallWrite(
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 *redundantWriteNodeName,
char *recoveryNodeName,
int (*recovFunc)(RF_DagNode_t *))
{
RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout);
RF_DagNode_t *nodes, *wudNodes, *rrdNodes, *recoveryNode, *blockNode, *unblockNode, *rpNodes,*rqNodes, *wpNodes, *wqNodes, *termNode;
RF_PhysDiskAddr_t *pda, *pqPDAs;
RF_PhysDiskAddr_t *npdas;
int nWriteNodes, nNodes, nReadNodes, nRrdNodes, nWudNodes, i;
RF_ReconUnitNum_t which_ru;
int nPQNodes;
RF_StripeNum_t parityStripeID = rf_RaidAddressToParityStripeID(layoutPtr, asmap->raidAddress, &which_ru);
/* simple small write case -
First part looks like a reconstruct-read of the failed data units.
Then a write of all data units not failed. */
/*
Hdr
|
------Block-
/ / \
Rrd Rrd ... Rrd Rp Rq
\ \ /
-------PQ-----
/ \ \
Wud Wp WQ
\ | /
--Unblock-
|
T
Rrd = read recovery data (potentially none)
Wud = write user data (not incl. failed disks)
Wp = Write P (could be two)
Wq = Write Q (could be two)
*/
rf_WriteGenerateFailedAccessASMs(raidPtr, asmap, &npdas, &nRrdNodes, &pqPDAs, &nPQNodes,allocList);
RF_ASSERT(asmap->numDataFailed == 1);
nWudNodes = asmap->numStripeUnitsAccessed - (asmap->numDataFailed);
nReadNodes = nRrdNodes + 2*nPQNodes;
nWriteNodes = nWudNodes+ 2*nPQNodes;
nNodes = 4 + nReadNodes + nWriteNodes;
RF_CallocAndAdd(nodes, nNodes, sizeof(RF_DagNode_t), (RF_DagNode_t *), allocList);
blockNode = nodes;
unblockNode = blockNode+1;
termNode = unblockNode+1;
recoveryNode = termNode+1;
rrdNodes = recoveryNode+1;
rpNodes = rrdNodes + nRrdNodes;
rqNodes = rpNodes + nPQNodes;
wudNodes = rqNodes + nPQNodes;
wpNodes = wudNodes + nWudNodes;
wqNodes = wpNodes + nPQNodes;
dag_h->creator = "PQ_DDSimpleSmallWrite";
dag_h->numSuccedents = 1;
dag_h->succedents[0] = blockNode;
rf_InitNode(termNode, rf_wait, RF_FALSE, rf_TerminateFunc, rf_TerminateUndoFunc, NULL, 0, 1, 0, 0, dag_h, "Trm", allocList);
termNode->antecedents[0] = unblockNode;
termNode->antType[0] = rf_control;
/* init the block and unblock nodes */
/* The block node has all the read nodes as successors */
rf_InitNode(blockNode, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc, NULL, nReadNodes, 0, 0, 0, dag_h, "Nil", allocList);
for (i=0; i < nReadNodes; i++)
blockNode->succedents[i] = rrdNodes+i;
/* The unblock node has all the writes as successors */
rf_InitNode(unblockNode, rf_wait, RF_FALSE, rf_NullNodeFunc, rf_NullNodeUndoFunc, NULL, 1, nWriteNodes, 0, 0, dag_h, "Nil", allocList);
for (i=0; i < nWriteNodes; i++) {
unblockNode->antecedents[i] = wudNodes+i;
unblockNode->antType[i] = rf_control;
}
unblockNode->succedents[0] = termNode;
#define INIT_READ_NODE(node,name) \
rf_InitNode(node, rf_wait, RF_FALSE, rf_DiskReadFunc, rf_DiskReadUndoFunc, rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, name, allocList); \
(node)->succedents[0] = recoveryNode; \
(node)->antecedents[0] = blockNode; \
(node)->antType[0] = rf_control;
/* build the read nodes */
pda = npdas;
for (i=0; i < nRrdNodes; i++, pda = pda->next) {
INIT_READ_NODE(rrdNodes+i,"rrd");
DISK_NODE_PARAMS(rrdNodes[i],pda);
}
/* read redundancy pdas */
pda = pqPDAs;
INIT_READ_NODE(rpNodes,"Rp");
RF_ASSERT(pda);
DISK_NODE_PARAMS(rpNodes[0],pda);
pda++;
INIT_READ_NODE(rqNodes, redundantReadNodeName );
RF_ASSERT(pda);
DISK_NODE_PARAMS(rqNodes[0],pda);
if (nPQNodes==2)
{
pda++;
INIT_READ_NODE(rpNodes+1,"Rp");
RF_ASSERT(pda);
DISK_NODE_PARAMS(rpNodes[1],pda);
pda++;
INIT_READ_NODE(rqNodes+1,redundantReadNodeName );
RF_ASSERT(pda);
DISK_NODE_PARAMS(rqNodes[1],pda);
}
/* the recovery node has all reads as precedessors and all writes as successors.
It generates a result for every write P or write Q node.
As parameters, it takes a pda per read and a pda per stripe of user data written.
It also takes as the last params the raidPtr and asm.
For results, it takes PDA for P & Q. */
rf_InitNode(recoveryNode, rf_wait, RF_FALSE, recovFunc, rf_NullNodeUndoFunc, NULL,
nWriteNodes, /* succesors */
nReadNodes, /* preds */
nReadNodes + nWudNodes + 3, /* params */
2 * nPQNodes, /* results */
dag_h, recoveryNodeName, allocList);
for (i=0; i < nReadNodes; i++ )
{
recoveryNode->antecedents[i] = rrdNodes+i;
recoveryNode->antType[i] = rf_control;
recoveryNode->params[i].p = DISK_NODE_PDA(rrdNodes+i);
}
for (i=0; i < nWudNodes; i++)
{
recoveryNode->succedents[i] = wudNodes+i;
}
recoveryNode->params[nReadNodes+nWudNodes].p = asmap->failedPDAs[0];
recoveryNode->params[nReadNodes+nWudNodes+1].p = raidPtr;
recoveryNode->params[nReadNodes+nWudNodes+2].p = asmap;
for ( ; i < nWriteNodes; i++)
recoveryNode->succedents[i] = wudNodes+i;
pda = pqPDAs;
recoveryNode->results[0] = pda;
pda++;
recoveryNode->results[1] = pda;
if ( nPQNodes == 2)
{
pda++;
recoveryNode->results[2] = pda;
pda++;
recoveryNode->results[3] = pda;
}
/* fill writes */
#define INIT_WRITE_NODE(node,name) \
rf_InitNode(node, rf_wait, RF_FALSE, rf_DiskWriteFunc, rf_DiskWriteUndoFunc, rf_GenericWakeupFunc, 1, 1, 4, 0, dag_h, name, allocList); \
(node)->succedents[0] = unblockNode; \
(node)->antecedents[0] = recoveryNode; \
(node)->antType[0] = rf_control;
pda = asmap->physInfo;
for (i=0; i < nWudNodes; i++)
{
INIT_WRITE_NODE(wudNodes+i,"Wd");
DISK_NODE_PARAMS(wudNodes[i],pda);
recoveryNode->params[nReadNodes+i].p = DISK_NODE_PDA(wudNodes+i);
pda = pda->next;
}
/* write redundancy pdas */
pda = pqPDAs;
INIT_WRITE_NODE(wpNodes,"Wp");
RF_ASSERT(pda);
DISK_NODE_PARAMS(wpNodes[0],pda);
pda++;
INIT_WRITE_NODE(wqNodes,"Wq");
RF_ASSERT(pda);
DISK_NODE_PARAMS(wqNodes[0],pda);
if (nPQNodes==2)
{
pda++;
INIT_WRITE_NODE(wpNodes+1,"Wp");
RF_ASSERT(pda);
DISK_NODE_PARAMS(wpNodes[1],pda);
pda++;
INIT_WRITE_NODE(wqNodes+1,"Wq");
RF_ASSERT(pda);
DISK_NODE_PARAMS(wqNodes[1],pda);
}
}