468 lines
15 KiB
C
468 lines
15 KiB
C
/* $NetBSD: rf_dagffrd.c,v 1.14 2005/02/27 00:27:44 perry 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_dagffrd.c
|
|
*
|
|
* code for creating fault-free read DAGs
|
|
*
|
|
*/
|
|
|
|
#include <sys/cdefs.h>
|
|
__KERNEL_RCSID(0, "$NetBSD: rf_dagffrd.c,v 1.14 2005/02/27 00:27:44 perry Exp $");
|
|
|
|
#include <dev/raidframe/raidframevar.h>
|
|
|
|
#include "rf_raid.h"
|
|
#include "rf_dag.h"
|
|
#include "rf_dagutils.h"
|
|
#include "rf_dagfuncs.h"
|
|
#include "rf_debugMem.h"
|
|
#include "rf_general.h"
|
|
#include "rf_dagffrd.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_CreateFaultFreeReadDAG(RF_Raid_t *raidPtr, RF_AccessStripeMap_t *asmap,
|
|
RF_DagHeader_t *dag_h, void *bp,
|
|
RF_RaidAccessFlags_t flags,
|
|
RF_AllocListElem_t *allocList)
|
|
{
|
|
rf_CreateNonredundantDAG(raidPtr, asmap, dag_h, bp, flags, allocList,
|
|
RF_IO_TYPE_READ);
|
|
}
|
|
|
|
|
|
/******************************************************************************
|
|
*
|
|
* DAG creation code begins here
|
|
*/
|
|
|
|
/******************************************************************************
|
|
*
|
|
* creates a DAG to perform a nonredundant read or write of data within one
|
|
* stripe.
|
|
* For reads, this DAG is as follows:
|
|
*
|
|
* /---- read ----\
|
|
* Header -- Block ---- read ---- Commit -- Terminate
|
|
* \---- read ----/
|
|
*
|
|
* For writes, this DAG is as follows:
|
|
*
|
|
* /---- write ----\
|
|
* Header -- Commit ---- write ---- Block -- Terminate
|
|
* \---- write ----/
|
|
*
|
|
* There is one disk node per stripe unit accessed, and all disk nodes are in
|
|
* parallel.
|
|
*
|
|
* Tricky point here: The first disk node (read or write) is created
|
|
* normally. Subsequent disk nodes are created by copying the first one,
|
|
* and modifying a few params. The "succedents" and "antecedents" fields are
|
|
* _not_ re-created in each node, but rather left pointing to the same array
|
|
* that was malloc'd when the first node was created. Thus, it's essential
|
|
* that when this DAG is freed, the succedents and antecedents fields be freed
|
|
* in ONLY ONE of the read nodes. This does not apply to the "params" field
|
|
* because it is recreated for each READ node.
|
|
*
|
|
* Note that normal-priority accesses do not need to be tagged with their
|
|
* parity stripe ID, because they will never be promoted. Hence, I've
|
|
* commented-out the code to do this, and marked it with UNNEEDED.
|
|
*
|
|
*****************************************************************************/
|
|
|
|
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 *diskNodes, *blockNode, *commitNode, *termNode;
|
|
RF_DagNode_t *tmpNode, *tmpdiskNode;
|
|
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_DEBUG_DAG
|
|
if (rf_dagDebug)
|
|
printf("[Creating non-redundant read DAG]\n");
|
|
#endif
|
|
break;
|
|
case RF_IO_TYPE_WRITE:
|
|
doFunc = rf_DiskWriteFunc;
|
|
undoFunc = rf_DiskWriteUndoFunc;
|
|
name = "W ";
|
|
#if RF_DEBUG_DAG
|
|
if (rf_dagDebug)
|
|
printf("[Creating non-redundant write DAG]\n");
|
|
#endif
|
|
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;
|
|
|
|
for (i = 0; i < n; i++) {
|
|
tmpNode = rf_AllocDAGNode();
|
|
tmpNode->list_next = dag_h->nodes;
|
|
dag_h->nodes = tmpNode;
|
|
}
|
|
diskNodes = dag_h->nodes;
|
|
|
|
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;
|
|
|
|
/* 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();
|
|
}
|
|
|
|
tmpdiskNode = diskNodes;
|
|
for (i = 0; i < n; i++) {
|
|
RF_ASSERT(pda != NULL);
|
|
rf_InitNode(tmpdiskNode, rf_wait, RF_FALSE, doFunc, undoFunc, rf_GenericWakeupFunc,
|
|
1, 1, 4, 0, dag_h, name, allocList);
|
|
tmpdiskNode->params[0].p = pda;
|
|
tmpdiskNode->params[1].p = pda->bufPtr;
|
|
/* parity stripe id is not necessary */
|
|
tmpdiskNode->params[2].v = 0;
|
|
tmpdiskNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, 0);
|
|
pda = pda->next;
|
|
tmpdiskNode = tmpdiskNode->list_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);
|
|
tmpdiskNode = diskNodes;
|
|
for (i = 0; i < n; i++) {
|
|
/* connect block node to each read node */
|
|
RF_ASSERT(tmpdiskNode->numAntecedents == 1);
|
|
blockNode->succedents[i] = tmpdiskNode;
|
|
tmpdiskNode->antecedents[0] = blockNode;
|
|
tmpdiskNode->antType[0] = rf_control;
|
|
|
|
/* connect each read node to the commit node */
|
|
RF_ASSERT(tmpdiskNode->numSuccedents == 1);
|
|
tmpdiskNode->succedents[0] = commitNode;
|
|
commitNode->antecedents[i] = tmpdiskNode;
|
|
commitNode->antType[i] = rf_control;
|
|
tmpdiskNode = tmpdiskNode->list_next;
|
|
}
|
|
/* 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);
|
|
tmpdiskNode = diskNodes;
|
|
for (i = 0; i < n; i++) {
|
|
/* connect the commit node to each write node */
|
|
RF_ASSERT(tmpdiskNode->numAntecedents == 1);
|
|
commitNode->succedents[i] = tmpdiskNode;
|
|
tmpdiskNode->antecedents[0] = commitNode;
|
|
tmpdiskNode->antType[0] = rf_control;
|
|
|
|
/* connect each write node to the term node */
|
|
RF_ASSERT(tmpdiskNode->numSuccedents == 1);
|
|
tmpdiskNode->succedents[0] = termNode;
|
|
termNode->antecedents[i] = tmpdiskNode;
|
|
termNode->antType[i] = rf_control;
|
|
tmpdiskNode = tmpdiskNode->list_next;
|
|
}
|
|
}
|
|
}
|
|
/******************************************************************************
|
|
* Create a fault-free read DAG for RAID level 1
|
|
*
|
|
* Hdr -> Nil -> Rmir -> Cmt -> Trm
|
|
*
|
|
* The "Rmir" node schedules a read from the disk in the mirror pair with the
|
|
* shortest disk queue. the proper queue is selected at Rmir execution. this
|
|
* deferred mapping is unlike other archs in RAIDframe which generally fix
|
|
* mapping at DAG creation time.
|
|
*
|
|
* Parameters: raidPtr - description of the physical array
|
|
* asmap - logical & physical addresses for this access
|
|
* bp - buffer ptr (for holding read data)
|
|
* flags - general flags (e.g. disk locking)
|
|
* allocList - list of memory allocated in DAG creation
|
|
*****************************************************************************/
|
|
|
|
static void
|
|
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 * node))
|
|
{
|
|
RF_DagNode_t *readNodes, *blockNode, *commitNode, *termNode;
|
|
RF_DagNode_t *tmpNode, *tmpreadNode;
|
|
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_DEBUG_DAG
|
|
if (rf_dagDebug) {
|
|
printf("[Creating RAID level 1 read DAG]\n");
|
|
}
|
|
#endif
|
|
/*
|
|
* 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;
|
|
|
|
for (i = 0; i < n; i++) {
|
|
tmpNode = rf_AllocDAGNode();
|
|
tmpNode->list_next = dag_h->nodes;
|
|
dag_h->nodes = tmpNode;
|
|
}
|
|
readNodes = dag_h->nodes;
|
|
|
|
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;
|
|
|
|
/* 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);
|
|
|
|
tmpreadNode = readNodes;
|
|
for (i = 0; i < n; i++) {
|
|
RF_ASSERT(data_pda != NULL);
|
|
RF_ASSERT(parity_pda != NULL);
|
|
rf_InitNode(tmpreadNode, rf_wait, RF_FALSE, readfunc,
|
|
rf_DiskReadMirrorUndoFunc, rf_GenericWakeupFunc, 1, 1, 5, 0, dag_h,
|
|
"Rmir", allocList);
|
|
tmpreadNode->params[0].p = data_pda;
|
|
tmpreadNode->params[1].p = data_pda->bufPtr;
|
|
/* parity stripe id is not necessary */
|
|
tmpreadNode->params[2].p = 0;
|
|
tmpreadNode->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, 0);
|
|
tmpreadNode->params[4].p = parity_pda;
|
|
data_pda = data_pda->next;
|
|
parity_pda = parity_pda->next;
|
|
tmpreadNode = tmpreadNode->list_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);
|
|
tmpreadNode = readNodes;
|
|
for (i = 0; i < n; i++) {
|
|
RF_ASSERT(tmpreadNode->numAntecedents == 1);
|
|
blockNode->succedents[i] = tmpreadNode;
|
|
tmpreadNode->antecedents[0] = blockNode;
|
|
tmpreadNode->antType[0] = rf_control;
|
|
tmpreadNode = tmpreadNode->list_next;
|
|
}
|
|
|
|
/* connect read nodes to commit node */
|
|
RF_ASSERT(commitNode->numAntecedents == n);
|
|
tmpreadNode = readNodes;
|
|
for (i = 0; i < n; i++) {
|
|
RF_ASSERT(tmpreadNode->numSuccedents == 1);
|
|
tmpreadNode->succedents[0] = commitNode;
|
|
commitNode->antecedents[i] = tmpreadNode;
|
|
commitNode->antType[i] = rf_control;
|
|
tmpreadNode = tmpreadNode->list_next;
|
|
}
|
|
|
|
/* 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_CreateMirrorIdleReadDAG(
|
|
RF_Raid_t * raidPtr,
|
|
RF_AccessStripeMap_t * asmap,
|
|
RF_DagHeader_t * dag_h,
|
|
void *bp,
|
|
RF_RaidAccessFlags_t flags,
|
|
RF_AllocListElem_t * allocList)
|
|
{
|
|
CreateMirrorReadDAG(raidPtr, asmap, dag_h, bp, flags, allocList,
|
|
rf_DiskReadMirrorIdleFunc);
|
|
}
|
|
|
|
#if (RF_INCLUDE_CHAINDECLUSTER > 0) || (RF_INCLUDE_INTERDECLUSTER > 0)
|
|
|
|
void
|
|
rf_CreateMirrorPartitionReadDAG(RF_Raid_t *raidPtr,
|
|
RF_AccessStripeMap_t *asmap,
|
|
RF_DagHeader_t *dag_h, void *bp,
|
|
RF_RaidAccessFlags_t flags,
|
|
RF_AllocListElem_t *allocList)
|
|
{
|
|
CreateMirrorReadDAG(raidPtr, asmap, dag_h, bp, flags, allocList,
|
|
rf_DiskReadMirrorPartitionFunc);
|
|
}
|
|
#endif
|