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rf_states.c revision 1.44.6.1
      1  1.44.6.1    jruoho /*	$NetBSD: rf_states.c,v 1.44.6.1 2011/06/06 09:08:34 jruoho Exp $	*/
      2       1.1     oster /*
      3       1.1     oster  * Copyright (c) 1995 Carnegie-Mellon University.
      4       1.1     oster  * All rights reserved.
      5       1.1     oster  *
      6       1.1     oster  * Author: Mark Holland, William V. Courtright II, Robby Findler
      7       1.1     oster  *
      8       1.1     oster  * Permission to use, copy, modify and distribute this software and
      9       1.1     oster  * its documentation is hereby granted, provided that both the copyright
     10       1.1     oster  * notice and this permission notice appear in all copies of the
     11       1.1     oster  * software, derivative works or modified versions, and any portions
     12       1.1     oster  * thereof, and that both notices appear in supporting documentation.
     13       1.1     oster  *
     14       1.1     oster  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
     15       1.1     oster  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
     16       1.1     oster  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
     17       1.1     oster  *
     18       1.1     oster  * Carnegie Mellon requests users of this software to return to
     19       1.1     oster  *
     20       1.1     oster  *  Software Distribution Coordinator  or  Software.Distribution (at) CS.CMU.EDU
     21       1.1     oster  *  School of Computer Science
     22       1.1     oster  *  Carnegie Mellon University
     23       1.1     oster  *  Pittsburgh PA 15213-3890
     24       1.1     oster  *
     25       1.1     oster  * any improvements or extensions that they make and grant Carnegie the
     26       1.1     oster  * rights to redistribute these changes.
     27       1.1     oster  */
     28      1.16     lukem 
     29      1.16     lukem #include <sys/cdefs.h>
     30  1.44.6.1    jruoho __KERNEL_RCSID(0, "$NetBSD: rf_states.c,v 1.44.6.1 2011/06/06 09:08:34 jruoho Exp $");
     31       1.1     oster 
     32       1.1     oster #include <sys/errno.h>
     33       1.1     oster 
     34       1.1     oster #include "rf_archs.h"
     35       1.1     oster #include "rf_threadstuff.h"
     36       1.1     oster #include "rf_raid.h"
     37       1.1     oster #include "rf_dag.h"
     38       1.1     oster #include "rf_desc.h"
     39       1.1     oster #include "rf_aselect.h"
     40       1.1     oster #include "rf_general.h"
     41       1.1     oster #include "rf_states.h"
     42       1.1     oster #include "rf_dagutils.h"
     43       1.1     oster #include "rf_driver.h"
     44       1.1     oster #include "rf_engine.h"
     45       1.1     oster #include "rf_map.h"
     46       1.1     oster #include "rf_etimer.h"
     47      1.10     oster #include "rf_kintf.h"
     48      1.44       jld #include "rf_paritymap.h"
     49       1.1     oster 
     50      1.19     oster #ifndef RF_DEBUG_STATES
     51      1.19     oster #define RF_DEBUG_STATES 0
     52      1.19     oster #endif
     53      1.19     oster 
     54       1.1     oster /* prototypes for some of the available states.
     55       1.1     oster 
     56       1.1     oster    States must:
     57       1.1     oster 
     58       1.1     oster      - not block.
     59       1.1     oster 
     60       1.1     oster      - either schedule rf_ContinueRaidAccess as a callback and return
     61       1.1     oster        RF_TRUE, or complete all of their work and return RF_FALSE.
     62       1.1     oster 
     63       1.1     oster      - increment desc->state when they have finished their work.
     64       1.1     oster */
     65       1.1     oster 
     66      1.19     oster #if RF_DEBUG_STATES
     67       1.6     oster static char *
     68       1.6     oster StateName(RF_AccessState_t state)
     69       1.1     oster {
     70       1.6     oster 	switch (state) {
     71       1.6     oster 		case rf_QuiesceState:return "QuiesceState";
     72       1.6     oster 	case rf_MapState:
     73       1.6     oster 		return "MapState";
     74       1.6     oster 	case rf_LockState:
     75       1.6     oster 		return "LockState";
     76       1.6     oster 	case rf_CreateDAGState:
     77       1.6     oster 		return "CreateDAGState";
     78       1.6     oster 	case rf_ExecuteDAGState:
     79       1.6     oster 		return "ExecuteDAGState";
     80       1.6     oster 	case rf_ProcessDAGState:
     81       1.6     oster 		return "ProcessDAGState";
     82       1.6     oster 	case rf_CleanupState:
     83       1.6     oster 		return "CleanupState";
     84       1.6     oster 	case rf_LastState:
     85       1.6     oster 		return "LastState";
     86       1.6     oster 	case rf_IncrAccessesCountState:
     87       1.6     oster 		return "IncrAccessesCountState";
     88       1.6     oster 	case rf_DecrAccessesCountState:
     89       1.6     oster 		return "DecrAccessesCountState";
     90       1.6     oster 	default:
     91       1.6     oster 		return "!!! UnnamedState !!!";
     92       1.6     oster 	}
     93       1.6     oster }
     94      1.19     oster #endif
     95       1.6     oster 
     96      1.38     perry void
     97      1.22     oster rf_ContinueRaidAccess(RF_RaidAccessDesc_t *desc)
     98       1.6     oster {
     99       1.6     oster 	int     suspended = RF_FALSE;
    100       1.6     oster 	int     current_state_index = desc->state;
    101       1.6     oster 	RF_AccessState_t current_state = desc->states[current_state_index];
    102      1.19     oster #if RF_DEBUG_STATES
    103      1.12     oster 	int     unit = desc->raidPtr->raidid;
    104      1.19     oster #endif
    105       1.6     oster 
    106       1.6     oster 	do {
    107       1.6     oster 
    108       1.6     oster 		current_state_index = desc->state;
    109       1.6     oster 		current_state = desc->states[current_state_index];
    110       1.6     oster 
    111       1.6     oster 		switch (current_state) {
    112       1.6     oster 
    113       1.6     oster 		case rf_QuiesceState:
    114       1.6     oster 			suspended = rf_State_Quiesce(desc);
    115       1.6     oster 			break;
    116       1.6     oster 		case rf_IncrAccessesCountState:
    117       1.6     oster 			suspended = rf_State_IncrAccessCount(desc);
    118       1.6     oster 			break;
    119       1.6     oster 		case rf_MapState:
    120       1.6     oster 			suspended = rf_State_Map(desc);
    121       1.6     oster 			break;
    122       1.6     oster 		case rf_LockState:
    123       1.6     oster 			suspended = rf_State_Lock(desc);
    124       1.6     oster 			break;
    125       1.6     oster 		case rf_CreateDAGState:
    126       1.6     oster 			suspended = rf_State_CreateDAG(desc);
    127       1.6     oster 			break;
    128       1.6     oster 		case rf_ExecuteDAGState:
    129       1.6     oster 			suspended = rf_State_ExecuteDAG(desc);
    130       1.6     oster 			break;
    131       1.6     oster 		case rf_ProcessDAGState:
    132       1.6     oster 			suspended = rf_State_ProcessDAG(desc);
    133       1.6     oster 			break;
    134       1.6     oster 		case rf_CleanupState:
    135       1.6     oster 			suspended = rf_State_Cleanup(desc);
    136       1.6     oster 			break;
    137       1.6     oster 		case rf_DecrAccessesCountState:
    138       1.6     oster 			suspended = rf_State_DecrAccessCount(desc);
    139       1.6     oster 			break;
    140       1.6     oster 		case rf_LastState:
    141       1.6     oster 			suspended = rf_State_LastState(desc);
    142       1.6     oster 			break;
    143       1.6     oster 		}
    144       1.6     oster 
    145      1.23     oster 		/* after this point, we cannot dereference desc since
    146      1.23     oster 		 * desc may have been freed. desc is only freed in
    147      1.23     oster 		 * LastState, so if we renter this function or loop
    148      1.23     oster 		 * back up, desc should be valid. */
    149       1.6     oster 
    150      1.19     oster #if RF_DEBUG_STATES
    151       1.6     oster 		if (rf_printStatesDebug) {
    152      1.12     oster 			printf("raid%d: State: %-24s StateIndex: %3i desc: 0x%ld %s\n",
    153      1.38     perry 			       unit, StateName(current_state),
    154      1.12     oster 			       current_state_index, (long) desc,
    155      1.12     oster 			       suspended ? "callback scheduled" : "looping");
    156       1.6     oster 		}
    157      1.19     oster #endif
    158       1.6     oster 	} while (!suspended && current_state != rf_LastState);
    159       1.6     oster 
    160       1.6     oster 	return;
    161       1.6     oster }
    162       1.6     oster 
    163       1.6     oster 
    164      1.38     perry void
    165      1.22     oster rf_ContinueDagAccess(RF_DagList_t *dagList)
    166       1.6     oster {
    167      1.27     oster #if RF_ACC_TRACE > 0
    168       1.6     oster 	RF_AccTraceEntry_t *tracerec = &(dagList->desc->tracerec);
    169      1.28     oster 	RF_Etimer_t timer;
    170      1.27     oster #endif
    171       1.6     oster 	RF_RaidAccessDesc_t *desc;
    172       1.6     oster 	RF_DagHeader_t *dag_h;
    173       1.6     oster 	int     i;
    174       1.6     oster 
    175       1.6     oster 	desc = dagList->desc;
    176       1.6     oster 
    177      1.27     oster #if RF_ACC_TRACE > 0
    178       1.6     oster 	timer = tracerec->timer;
    179       1.6     oster 	RF_ETIMER_STOP(timer);
    180       1.6     oster 	RF_ETIMER_EVAL(timer);
    181       1.6     oster 	tracerec->specific.user.exec_us = RF_ETIMER_VAL_US(timer);
    182       1.6     oster 	RF_ETIMER_START(tracerec->timer);
    183      1.27     oster #endif
    184       1.6     oster 
    185       1.6     oster 	/* skip to dag which just finished */
    186       1.6     oster 	dag_h = dagList->dags;
    187       1.6     oster 	for (i = 0; i < dagList->numDagsDone; i++) {
    188       1.6     oster 		dag_h = dag_h->next;
    189       1.6     oster 	}
    190       1.6     oster 
    191       1.6     oster 	/* check to see if retry is required */
    192       1.6     oster 	if (dag_h->status == rf_rollBackward) {
    193      1.23     oster 		/* when a dag fails, mark desc status as bad and allow
    194      1.23     oster 		 * all other dags in the desc to execute to
    195      1.23     oster 		 * completion.  then, free all dags and start over */
    196       1.6     oster 		desc->status = 1;	/* bad status */
    197      1.25     oster #if 0
    198      1.25     oster 		printf("raid%d: DAG failure: %c addr 0x%lx "
    199      1.25     oster 		       "(%ld) nblk 0x%x (%d) buf 0x%lx state %d\n",
    200      1.38     perry 		       desc->raidPtr->raidid, desc->type,
    201      1.23     oster 		       (long) desc->raidAddress,
    202      1.23     oster 		       (long) desc->raidAddress, (int) desc->numBlocks,
    203      1.38     perry 		       (int) desc->numBlocks,
    204      1.25     oster 		       (unsigned long) (desc->bufPtr), desc->state);
    205      1.25     oster #endif
    206       1.6     oster 	}
    207       1.6     oster 	dagList->numDagsDone++;
    208       1.6     oster 	rf_ContinueRaidAccess(desc);
    209       1.6     oster }
    210       1.6     oster 
    211      1.38     perry int
    212      1.22     oster rf_State_LastState(RF_RaidAccessDesc_t *desc)
    213       1.1     oster {
    214       1.6     oster 	void    (*callbackFunc) (RF_CBParam_t) = desc->callbackFunc;
    215       1.6     oster 	RF_CBParam_t callbackArg;
    216       1.2  drochner 
    217       1.6     oster 	callbackArg.p = desc->callbackArg;
    218      1.38     perry 
    219       1.8     oster 	/*
    220  1.44.6.1    jruoho 	 * We don't support non-async IO.
    221       1.8     oster 	 */
    222  1.44.6.1    jruoho 	KASSERT(desc->async_flag);
    223      1.15     oster 
    224      1.15     oster 	/*
    225      1.15     oster 	 * That's all the IO for this one... unbusy the 'disk'.
    226      1.15     oster 	 */
    227      1.15     oster 
    228      1.15     oster 	rf_disk_unbusy(desc);
    229      1.15     oster 
    230      1.38     perry 	/*
    231       1.8     oster 	 * Wakeup any requests waiting to go.
    232       1.8     oster 	 */
    233      1.38     perry 
    234  1.44.6.1    jruoho 	rf_lock_mutex2(desc->raidPtr->mutex);
    235  1.44.6.1    jruoho 	desc->raidPtr->openings++;
    236  1.44.6.1    jruoho 	rf_unlock_mutex2(desc->raidPtr->mutex);
    237  1.44.6.1    jruoho 
    238  1.44.6.1    jruoho 	rf_lock_mutex2(desc->raidPtr->iodone_lock);
    239  1.44.6.1    jruoho 	rf_signal_cond2(desc->raidPtr->iodone_cv);
    240  1.44.6.1    jruoho 	rf_unlock_mutex2(desc->raidPtr->iodone_lock);
    241      1.38     perry 
    242      1.44       jld 	/*
    243      1.44       jld 	 * The parity_map hook has to go here, because the iodone
    244      1.44       jld 	 * callback goes straight into the kintf layer.
    245      1.44       jld 	 */
    246      1.44       jld 	if (desc->raidPtr->parity_map != NULL &&
    247      1.44       jld 	    desc->type == RF_IO_TYPE_WRITE)
    248      1.44       jld 		rf_paritymap_end(desc->raidPtr->parity_map,
    249      1.44       jld 		    desc->raidAddress, desc->numBlocks);
    250      1.44       jld 
    251       1.8     oster 	/* printf("Calling biodone on 0x%x\n",desc->bp); */
    252       1.8     oster 	biodone(desc->bp);	/* access came through ioctl */
    253       1.3  explorer 
    254       1.6     oster 	if (callbackFunc)
    255       1.6     oster 		callbackFunc(callbackArg);
    256       1.6     oster 	rf_FreeRaidAccDesc(desc);
    257       1.6     oster 
    258       1.6     oster 	return RF_FALSE;
    259       1.6     oster }
    260       1.6     oster 
    261      1.38     perry int
    262      1.22     oster rf_State_IncrAccessCount(RF_RaidAccessDesc_t *desc)
    263       1.6     oster {
    264       1.6     oster 	RF_Raid_t *raidPtr;
    265       1.6     oster 
    266       1.6     oster 	raidPtr = desc->raidPtr;
    267       1.6     oster 	/* Bummer. We have to do this to be 100% safe w.r.t. the increment
    268       1.6     oster 	 * below */
    269  1.44.6.1    jruoho 	rf_lock_mutex2(raidPtr->access_suspend_mutex);
    270       1.6     oster 	raidPtr->accs_in_flight++;	/* used to detect quiescence */
    271  1.44.6.1    jruoho 	rf_unlock_mutex2(raidPtr->access_suspend_mutex);
    272       1.6     oster 
    273       1.6     oster 	desc->state++;
    274       1.6     oster 	return RF_FALSE;
    275       1.6     oster }
    276       1.6     oster 
    277      1.38     perry int
    278      1.22     oster rf_State_DecrAccessCount(RF_RaidAccessDesc_t *desc)
    279       1.6     oster {
    280       1.6     oster 	RF_Raid_t *raidPtr;
    281       1.6     oster 
    282       1.6     oster 	raidPtr = desc->raidPtr;
    283       1.6     oster 
    284  1.44.6.1    jruoho 	rf_lock_mutex2(raidPtr->access_suspend_mutex);
    285       1.6     oster 	raidPtr->accs_in_flight--;
    286       1.6     oster 	if (raidPtr->accesses_suspended && raidPtr->accs_in_flight == 0) {
    287      1.20     oster 		rf_SignalQuiescenceLock(raidPtr);
    288       1.6     oster 	}
    289  1.44.6.1    jruoho 	rf_unlock_mutex2(raidPtr->access_suspend_mutex);
    290       1.6     oster 
    291       1.6     oster 	desc->state++;
    292       1.6     oster 	return RF_FALSE;
    293       1.6     oster }
    294       1.6     oster 
    295      1.38     perry int
    296      1.22     oster rf_State_Quiesce(RF_RaidAccessDesc_t *desc)
    297       1.6     oster {
    298      1.27     oster #if RF_ACC_TRACE > 0
    299       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    300       1.6     oster 	RF_Etimer_t timer;
    301      1.27     oster #endif
    302      1.31     oster 	RF_CallbackDesc_t *cb;
    303      1.31     oster 	RF_Raid_t *raidPtr;
    304       1.6     oster 	int     suspended = RF_FALSE;
    305      1.31     oster 	int need_cb, used_cb;
    306       1.6     oster 
    307       1.6     oster 	raidPtr = desc->raidPtr;
    308       1.6     oster 
    309      1.27     oster #if RF_ACC_TRACE > 0
    310       1.6     oster 	RF_ETIMER_START(timer);
    311       1.6     oster 	RF_ETIMER_START(desc->timer);
    312      1.27     oster #endif
    313       1.6     oster 
    314      1.31     oster 	need_cb = 0;
    315      1.31     oster 	used_cb = 0;
    316      1.31     oster 	cb = NULL;
    317      1.31     oster 
    318  1.44.6.1    jruoho 	rf_lock_mutex2(raidPtr->access_suspend_mutex);
    319      1.31     oster 	/* Do an initial check to see if we might need a callback structure */
    320       1.6     oster 	if (raidPtr->accesses_suspended) {
    321      1.31     oster 		need_cb = 1;
    322      1.31     oster 	}
    323  1.44.6.1    jruoho 	rf_unlock_mutex2(raidPtr->access_suspend_mutex);
    324      1.31     oster 
    325      1.31     oster 	if (need_cb) {
    326      1.31     oster 		/* create a callback if we might need it...
    327      1.31     oster 		   and we likely do. */
    328       1.6     oster 		cb = rf_AllocCallbackDesc();
    329      1.31     oster 	}
    330      1.23     oster 
    331  1.44.6.1    jruoho 	rf_lock_mutex2(raidPtr->access_suspend_mutex);
    332      1.31     oster 	if (raidPtr->accesses_suspended) {
    333       1.6     oster 		cb->callbackFunc = (void (*) (RF_CBParam_t)) rf_ContinueRaidAccess;
    334       1.6     oster 		cb->callbackArg.p = (void *) desc;
    335       1.6     oster 		cb->next = raidPtr->quiesce_wait_list;
    336       1.6     oster 		raidPtr->quiesce_wait_list = cb;
    337       1.6     oster 		suspended = RF_TRUE;
    338      1.31     oster 		used_cb = 1;
    339       1.6     oster 	}
    340  1.44.6.1    jruoho 	rf_unlock_mutex2(raidPtr->access_suspend_mutex);
    341       1.6     oster 
    342      1.31     oster 	if ((need_cb == 1) && (used_cb == 0)) {
    343      1.31     oster 		rf_FreeCallbackDesc(cb);
    344      1.31     oster 	}
    345      1.31     oster 
    346      1.27     oster #if RF_ACC_TRACE > 0
    347       1.6     oster 	RF_ETIMER_STOP(timer);
    348       1.6     oster 	RF_ETIMER_EVAL(timer);
    349       1.6     oster 	tracerec->specific.user.suspend_ovhd_us += RF_ETIMER_VAL_US(timer);
    350      1.27     oster #endif
    351       1.6     oster 
    352      1.18     oster #if RF_DEBUG_QUIESCE
    353       1.6     oster 	if (suspended && rf_quiesceDebug)
    354       1.6     oster 		printf("Stalling access due to quiescence lock\n");
    355      1.18     oster #endif
    356       1.6     oster 	desc->state++;
    357       1.6     oster 	return suspended;
    358       1.6     oster }
    359       1.6     oster 
    360      1.38     perry int
    361      1.22     oster rf_State_Map(RF_RaidAccessDesc_t *desc)
    362       1.6     oster {
    363       1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    364      1.27     oster #if RF_ACC_TRACE > 0
    365       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    366       1.6     oster 	RF_Etimer_t timer;
    367       1.6     oster 
    368       1.6     oster 	RF_ETIMER_START(timer);
    369      1.27     oster #endif
    370       1.6     oster 
    371       1.6     oster 	if (!(desc->asmap = rf_MapAccess(raidPtr, desc->raidAddress, desc->numBlocks,
    372       1.6     oster 		    desc->bufPtr, RF_DONT_REMAP)))
    373       1.6     oster 		RF_PANIC();
    374       1.6     oster 
    375      1.27     oster #if RF_ACC_TRACE > 0
    376       1.6     oster 	RF_ETIMER_STOP(timer);
    377       1.6     oster 	RF_ETIMER_EVAL(timer);
    378       1.6     oster 	tracerec->specific.user.map_us = RF_ETIMER_VAL_US(timer);
    379      1.27     oster #endif
    380       1.6     oster 
    381       1.6     oster 	desc->state++;
    382       1.6     oster 	return RF_FALSE;
    383       1.6     oster }
    384       1.6     oster 
    385      1.38     perry int
    386      1.22     oster rf_State_Lock(RF_RaidAccessDesc_t *desc)
    387       1.6     oster {
    388      1.27     oster #if RF_ACC_TRACE > 0
    389       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    390      1.28     oster 	RF_Etimer_t timer;
    391      1.27     oster #endif
    392       1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    393       1.6     oster 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    394       1.6     oster 	RF_AccessStripeMap_t *asm_p;
    395      1.32     oster 	RF_StripeNum_t lastStripeID = -1;
    396       1.6     oster 	int     suspended = RF_FALSE;
    397       1.6     oster 
    398      1.27     oster #if RF_ACC_TRACE > 0
    399       1.6     oster 	RF_ETIMER_START(timer);
    400      1.27     oster #endif
    401      1.38     perry 
    402      1.32     oster 	/* acquire each lock that we don't already hold */
    403      1.32     oster 	for (asm_p = asmh->stripeMap; asm_p; asm_p = asm_p->next) {
    404      1.32     oster 		RF_ASSERT(RF_IO_IS_R_OR_W(desc->type));
    405      1.32     oster 		if (!rf_suppressLocksAndLargeWrites &&
    406      1.32     oster 		    asm_p->parityInfo &&
    407      1.32     oster 		    !(desc->flags & RF_DAG_SUPPRESS_LOCKS) &&
    408      1.32     oster 		    !(asm_p->flags & RF_ASM_FLAGS_LOCK_TRIED)) {
    409      1.32     oster 			asm_p->flags |= RF_ASM_FLAGS_LOCK_TRIED;
    410      1.23     oster 				/* locks must be acquired hierarchically */
    411      1.32     oster 			RF_ASSERT(asm_p->stripeID > lastStripeID);
    412      1.32     oster 			lastStripeID = asm_p->stripeID;
    413      1.38     perry 
    414      1.32     oster 			RF_INIT_LOCK_REQ_DESC(asm_p->lockReqDesc, desc->type,
    415      1.32     oster 					      (void (*) (struct buf *)) rf_ContinueRaidAccess, desc, asm_p,
    416      1.32     oster 					      raidPtr->Layout.dataSectorsPerStripe);
    417      1.32     oster 			if (rf_AcquireStripeLock(raidPtr->lockTable, asm_p->stripeID,
    418      1.32     oster 						 &asm_p->lockReqDesc)) {
    419      1.32     oster 				suspended = RF_TRUE;
    420      1.32     oster 				break;
    421      1.32     oster 			}
    422      1.32     oster 		}
    423      1.32     oster 		if (desc->type == RF_IO_TYPE_WRITE &&
    424      1.32     oster 		    raidPtr->status == rf_rs_reconstructing) {
    425      1.32     oster 			if (!(asm_p->flags & RF_ASM_FLAGS_FORCE_TRIED)) {
    426      1.32     oster 				int     val;
    427      1.38     perry 
    428      1.32     oster 				asm_p->flags |= RF_ASM_FLAGS_FORCE_TRIED;
    429      1.32     oster 				val = rf_ForceOrBlockRecon(raidPtr, asm_p,
    430      1.32     oster 							   (void (*) (RF_Raid_t *, void *)) rf_ContinueRaidAccess, desc);
    431      1.32     oster 				if (val == 0) {
    432      1.32     oster 					asm_p->flags |= RF_ASM_FLAGS_RECON_BLOCKED;
    433      1.32     oster 				} else {
    434       1.6     oster 					suspended = RF_TRUE;
    435       1.6     oster 					break;
    436       1.6     oster 				}
    437       1.6     oster 			} else {
    438      1.29     oster #if RF_DEBUG_PSS > 0
    439       1.6     oster 				if (rf_pssDebug) {
    440      1.32     oster 					printf("raid%d: skipping force/block because already done, psid %ld\n",
    441      1.38     perry 					       desc->raidPtr->raidid,
    442      1.13     oster 					       (long) asm_p->stripeID);
    443       1.6     oster 				}
    444      1.29     oster #endif
    445       1.6     oster 			}
    446      1.32     oster 		} else {
    447      1.32     oster #if RF_DEBUG_PSS > 0
    448      1.32     oster 			if (rf_pssDebug) {
    449      1.32     oster 				printf("raid%d: skipping force/block because not write or not under recon, psid %ld\n",
    450      1.38     perry 				       desc->raidPtr->raidid,
    451      1.32     oster 				       (long) asm_p->stripeID);
    452      1.32     oster 			}
    453      1.32     oster #endif
    454       1.6     oster 		}
    455      1.32     oster 	}
    456      1.27     oster #if RF_ACC_TRACE > 0
    457      1.32     oster 	RF_ETIMER_STOP(timer);
    458      1.32     oster 	RF_ETIMER_EVAL(timer);
    459      1.32     oster 	tracerec->specific.user.lock_us += RF_ETIMER_VAL_US(timer);
    460      1.27     oster #endif
    461      1.32     oster 	if (suspended)
    462      1.32     oster 		return (RF_TRUE);
    463      1.32     oster 
    464       1.6     oster 	desc->state++;
    465       1.6     oster 	return (RF_FALSE);
    466       1.1     oster }
    467       1.1     oster /*
    468       1.1     oster  * the following three states create, execute, and post-process dags
    469       1.1     oster  * the error recovery unit is a single dag.
    470       1.1     oster  * by default, SelectAlgorithm creates an array of dags, one per parity stripe
    471       1.1     oster  * in some tricky cases, multiple dags per stripe are created
    472       1.1     oster  *   - dags within a parity stripe are executed sequentially (arbitrary order)
    473       1.1     oster  *   - dags for distinct parity stripes are executed concurrently
    474       1.1     oster  *
    475       1.1     oster  * repeat until all dags complete successfully -or- dag selection fails
    476       1.1     oster  *
    477       1.1     oster  * while !done
    478       1.1     oster  *   create dag(s) (SelectAlgorithm)
    479       1.1     oster  *   if dag
    480       1.1     oster  *     execute dag (DispatchDAG)
    481       1.1     oster  *     if dag successful
    482       1.1     oster  *       done (SUCCESS)
    483       1.1     oster  *     else
    484       1.1     oster  *       !done (RETRY - start over with new dags)
    485       1.1     oster  *   else
    486       1.1     oster  *     done (FAIL)
    487       1.1     oster  */
    488      1.38     perry int
    489      1.22     oster rf_State_CreateDAG(RF_RaidAccessDesc_t *desc)
    490       1.1     oster {
    491      1.27     oster #if RF_ACC_TRACE > 0
    492       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    493       1.6     oster 	RF_Etimer_t timer;
    494      1.27     oster #endif
    495       1.6     oster 	RF_DagHeader_t *dag_h;
    496      1.26     oster 	RF_DagList_t *dagList;
    497      1.25     oster 	struct buf *bp;
    498       1.6     oster 	int     i, selectStatus;
    499       1.6     oster 
    500       1.6     oster 	/* generate a dag for the access, and fire it off.  When the dag
    501       1.6     oster 	 * completes, we'll get re-invoked in the next state. */
    502      1.27     oster #if RF_ACC_TRACE > 0
    503       1.6     oster 	RF_ETIMER_START(timer);
    504      1.27     oster #endif
    505       1.6     oster 	/* SelectAlgorithm returns one or more dags */
    506       1.6     oster 	selectStatus = rf_SelectAlgorithm(desc, desc->flags | RF_DAG_SUPPRESS_LOCKS);
    507      1.17     oster #if RF_DEBUG_VALIDATE_DAG
    508      1.26     oster 	if (rf_printDAGsDebug) {
    509      1.26     oster 		dagList = desc->dagList;
    510      1.26     oster 		for (i = 0; i < desc->numStripes; i++) {
    511      1.42     oster 			rf_PrintDAGList(dagList->dags);
    512      1.26     oster 			dagList = dagList->next;
    513      1.26     oster 		}
    514      1.26     oster 	}
    515      1.17     oster #endif /* RF_DEBUG_VALIDATE_DAG */
    516      1.27     oster #if RF_ACC_TRACE > 0
    517       1.6     oster 	RF_ETIMER_STOP(timer);
    518       1.6     oster 	RF_ETIMER_EVAL(timer);
    519       1.6     oster 	/* update time to create all dags */
    520       1.6     oster 	tracerec->specific.user.dag_create_us = RF_ETIMER_VAL_US(timer);
    521      1.27     oster #endif
    522       1.6     oster 
    523       1.6     oster 	desc->status = 0;	/* good status */
    524       1.6     oster 
    525      1.36     oster 	if (selectStatus || (desc->numRetries > RF_RETRY_THRESHOLD)) {
    526       1.6     oster 		/* failed to create a dag */
    527       1.6     oster 		/* this happens when there are too many faults or incomplete
    528       1.6     oster 		 * dag libraries */
    529      1.36     oster 		if (selectStatus) {
    530      1.36     oster 			printf("raid%d: failed to create a dag. "
    531      1.38     perry 			       "Too many component failures.\n",
    532      1.36     oster 			       desc->raidPtr->raidid);
    533      1.36     oster 		} else {
    534      1.36     oster 			printf("raid%d: IO failed after %d retries.\n",
    535      1.36     oster 			       desc->raidPtr->raidid, RF_RETRY_THRESHOLD);
    536      1.36     oster 		}
    537      1.25     oster 
    538      1.38     perry 		desc->status = 1; /* bad status */
    539      1.25     oster 		/* skip straight to rf_State_Cleanup() */
    540      1.25     oster 		desc->state = rf_CleanupState;
    541      1.25     oster 		bp = (struct buf *)desc->bp;
    542      1.25     oster 		bp->b_error = EIO;
    543      1.43     oster 		bp->b_resid = bp->b_bcount;
    544       1.6     oster 	} else {
    545       1.6     oster 		/* bind dags to desc */
    546      1.26     oster 		dagList = desc->dagList;
    547       1.6     oster 		for (i = 0; i < desc->numStripes; i++) {
    548      1.26     oster 			dag_h = dagList->dags;
    549       1.6     oster 			while (dag_h) {
    550       1.6     oster 				dag_h->bp = (struct buf *) desc->bp;
    551      1.27     oster #if RF_ACC_TRACE > 0
    552       1.6     oster 				dag_h->tracerec = tracerec;
    553      1.27     oster #endif
    554       1.6     oster 				dag_h = dag_h->next;
    555       1.6     oster 			}
    556      1.26     oster 			dagList = dagList->next;
    557       1.6     oster 		}
    558       1.6     oster 		desc->flags |= RF_DAG_DISPATCH_RETURNED;
    559       1.6     oster 		desc->state++;	/* next state should be rf_State_ExecuteDAG */
    560       1.6     oster 	}
    561       1.6     oster 	return RF_FALSE;
    562       1.1     oster }
    563       1.1     oster 
    564       1.1     oster 
    565       1.1     oster 
    566      1.26     oster /* the access has an list of dagLists, one dagList per parity stripe.
    567       1.1     oster  * fire the first dag in each parity stripe (dagList).
    568       1.1     oster  * dags within a stripe (dagList) must be executed sequentially
    569       1.1     oster  *  - this preserves atomic parity update
    570       1.1     oster  * dags for independents parity groups (stripes) are fired concurrently */
    571       1.1     oster 
    572      1.38     perry int
    573      1.22     oster rf_State_ExecuteDAG(RF_RaidAccessDesc_t *desc)
    574       1.1     oster {
    575       1.6     oster 	int     i;
    576       1.6     oster 	RF_DagHeader_t *dag_h;
    577      1.26     oster 	RF_DagList_t *dagList;
    578       1.6     oster 
    579      1.23     oster 	/* next state is always rf_State_ProcessDAG important to do
    580      1.23     oster 	 * this before firing the first dag (it may finish before we
    581      1.23     oster 	 * leave this routine) */
    582       1.6     oster 	desc->state++;
    583       1.6     oster 
    584      1.23     oster 	/* sweep dag array, a stripe at a time, firing the first dag
    585      1.23     oster 	 * in each stripe */
    586      1.26     oster 	dagList = desc->dagList;
    587       1.6     oster 	for (i = 0; i < desc->numStripes; i++) {
    588      1.26     oster 		RF_ASSERT(dagList->numDags > 0);
    589      1.26     oster 		RF_ASSERT(dagList->numDagsDone == 0);
    590      1.26     oster 		RF_ASSERT(dagList->numDagsFired == 0);
    591      1.27     oster #if RF_ACC_TRACE > 0
    592      1.26     oster 		RF_ETIMER_START(dagList->tracerec.timer);
    593      1.27     oster #endif
    594       1.6     oster 		/* fire first dag in this stripe */
    595      1.26     oster 		dag_h = dagList->dags;
    596       1.6     oster 		RF_ASSERT(dag_h);
    597      1.26     oster 		dagList->numDagsFired++;
    598      1.26     oster 		rf_DispatchDAG(dag_h, (void (*) (void *)) rf_ContinueDagAccess, dagList);
    599      1.26     oster 		dagList = dagList->next;
    600       1.6     oster 	}
    601       1.6     oster 
    602       1.6     oster 	/* the DAG will always call the callback, even if there was no
    603       1.6     oster 	 * blocking, so we are always suspended in this state */
    604       1.6     oster 	return RF_TRUE;
    605       1.1     oster }
    606       1.1     oster 
    607       1.1     oster 
    608       1.1     oster 
    609       1.1     oster /* rf_State_ProcessDAG is entered when a dag completes.
    610       1.1     oster  * first, check to all dags in the access have completed
    611       1.1     oster  * if not, fire as many dags as possible */
    612       1.1     oster 
    613      1.38     perry int
    614      1.22     oster rf_State_ProcessDAG(RF_RaidAccessDesc_t *desc)
    615       1.1     oster {
    616       1.6     oster 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    617       1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    618       1.6     oster 	RF_DagHeader_t *dag_h;
    619       1.6     oster 	int     i, j, done = RF_TRUE;
    620      1.26     oster 	RF_DagList_t *dagList, *temp;
    621       1.6     oster 
    622       1.6     oster 	/* check to see if this is the last dag */
    623      1.26     oster 	dagList = desc->dagList;
    624      1.26     oster 	for (i = 0; i < desc->numStripes; i++) {
    625      1.26     oster 		if (dagList->numDags != dagList->numDagsDone)
    626       1.6     oster 			done = RF_FALSE;
    627      1.26     oster 		dagList = dagList->next;
    628      1.26     oster 	}
    629       1.6     oster 
    630       1.6     oster 	if (done) {
    631       1.6     oster 		if (desc->status) {
    632       1.6     oster 			/* a dag failed, retry */
    633       1.6     oster 			/* free all dags */
    634      1.26     oster 			dagList = desc->dagList;
    635       1.6     oster 			for (i = 0; i < desc->numStripes; i++) {
    636      1.26     oster 				rf_FreeDAG(dagList->dags);
    637      1.26     oster 				temp = dagList;
    638      1.35     oster 				dagList = dagList->next;
    639      1.34     oster 				rf_FreeDAGList(temp);
    640       1.6     oster 			}
    641      1.37     oster 			desc->dagList = NULL;
    642      1.37     oster 
    643       1.6     oster 			rf_MarkFailuresInASMList(raidPtr, asmh);
    644      1.36     oster 
    645      1.36     oster 			/* note the retry so that we'll bail in
    646      1.36     oster 			   rf_State_CreateDAG() once we've retired
    647      1.36     oster 			   the IO RF_RETRY_THRESHOLD times */
    648      1.36     oster 
    649      1.36     oster 			desc->numRetries++;
    650      1.36     oster 
    651       1.6     oster 			/* back up to rf_State_CreateDAG */
    652       1.6     oster 			desc->state = desc->state - 2;
    653       1.6     oster 			return RF_FALSE;
    654       1.6     oster 		} else {
    655       1.6     oster 			/* move on to rf_State_Cleanup */
    656       1.6     oster 			desc->state++;
    657       1.6     oster 		}
    658       1.6     oster 		return RF_FALSE;
    659       1.6     oster 	} else {
    660       1.6     oster 		/* more dags to execute */
    661       1.6     oster 		/* see if any are ready to be fired.  if so, fire them */
    662       1.6     oster 		/* don't fire the initial dag in a list, it's fired in
    663       1.6     oster 		 * rf_State_ExecuteDAG */
    664      1.26     oster 		dagList = desc->dagList;
    665       1.6     oster 		for (i = 0; i < desc->numStripes; i++) {
    666      1.26     oster 			if ((dagList->numDagsDone < dagList->numDags)
    667      1.26     oster 			    && (dagList->numDagsDone == dagList->numDagsFired)
    668      1.26     oster 			    && (dagList->numDagsFired > 0)) {
    669      1.27     oster #if RF_ACC_TRACE > 0
    670      1.26     oster 				RF_ETIMER_START(dagList->tracerec.timer);
    671      1.27     oster #endif
    672       1.6     oster 				/* fire next dag in this stripe */
    673       1.6     oster 				/* first, skip to next dag awaiting execution */
    674      1.26     oster 				dag_h = dagList->dags;
    675      1.26     oster 				for (j = 0; j < dagList->numDagsDone; j++)
    676       1.6     oster 					dag_h = dag_h->next;
    677      1.26     oster 				dagList->numDagsFired++;
    678       1.6     oster 				rf_DispatchDAG(dag_h, (void (*) (void *)) rf_ContinueDagAccess,
    679      1.26     oster 				    dagList);
    680       1.6     oster 			}
    681      1.26     oster 			dagList = dagList->next;
    682       1.6     oster 		}
    683       1.6     oster 		return RF_TRUE;
    684       1.6     oster 	}
    685       1.1     oster }
    686       1.1     oster /* only make it this far if all dags complete successfully */
    687      1.38     perry int
    688      1.22     oster rf_State_Cleanup(RF_RaidAccessDesc_t *desc)
    689       1.1     oster {
    690      1.27     oster #if RF_ACC_TRACE > 0
    691       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    692      1.28     oster 	RF_Etimer_t timer;
    693      1.27     oster #endif
    694       1.6     oster 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    695       1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    696       1.6     oster 	RF_AccessStripeMap_t *asm_p;
    697      1.26     oster 	RF_DagList_t *dagList;
    698      1.11     oster 	int i;
    699       1.6     oster 
    700       1.6     oster 	desc->state++;
    701       1.6     oster 
    702      1.27     oster #if RF_ACC_TRACE > 0
    703       1.6     oster 	timer = tracerec->timer;
    704       1.6     oster 	RF_ETIMER_STOP(timer);
    705       1.6     oster 	RF_ETIMER_EVAL(timer);
    706       1.6     oster 	tracerec->specific.user.dag_retry_us = RF_ETIMER_VAL_US(timer);
    707       1.6     oster 
    708       1.6     oster 	/* the RAID I/O is complete.  Clean up. */
    709       1.6     oster 	tracerec->specific.user.dag_retry_us = 0;
    710       1.6     oster 
    711       1.6     oster 	RF_ETIMER_START(timer);
    712      1.27     oster #endif
    713      1.24     oster 	/* free all dags */
    714      1.26     oster 	dagList = desc->dagList;
    715      1.24     oster 	for (i = 0; i < desc->numStripes; i++) {
    716      1.26     oster 		rf_FreeDAG(dagList->dags);
    717      1.26     oster 		dagList = dagList->next;
    718       1.6     oster 	}
    719      1.27     oster #if RF_ACC_TRACE > 0
    720       1.6     oster 	RF_ETIMER_STOP(timer);
    721       1.6     oster 	RF_ETIMER_EVAL(timer);
    722       1.6     oster 	tracerec->specific.user.cleanup_us = RF_ETIMER_VAL_US(timer);
    723       1.6     oster 
    724       1.6     oster 	RF_ETIMER_START(timer);
    725      1.27     oster #endif
    726      1.32     oster 	for (asm_p = asmh->stripeMap; asm_p; asm_p = asm_p->next) {
    727      1.32     oster 		if (!rf_suppressLocksAndLargeWrites &&
    728      1.32     oster 		    asm_p->parityInfo &&
    729      1.32     oster 		    !(desc->flags & RF_DAG_SUPPRESS_LOCKS)) {
    730      1.32     oster 			RF_ASSERT_VALID_LOCKREQ(&asm_p->lockReqDesc);
    731      1.38     perry 			rf_ReleaseStripeLock(raidPtr->lockTable,
    732      1.32     oster 					     asm_p->stripeID,
    733      1.32     oster 					     &asm_p->lockReqDesc);
    734      1.32     oster 		}
    735      1.32     oster 		if (asm_p->flags & RF_ASM_FLAGS_RECON_BLOCKED) {
    736      1.32     oster 			rf_UnblockRecon(raidPtr, asm_p);
    737       1.6     oster 		}
    738       1.6     oster 	}
    739      1.27     oster #if RF_ACC_TRACE > 0
    740       1.6     oster 	RF_ETIMER_STOP(timer);
    741       1.6     oster 	RF_ETIMER_EVAL(timer);
    742       1.6     oster 	tracerec->specific.user.lock_us += RF_ETIMER_VAL_US(timer);
    743       1.6     oster 
    744       1.6     oster 	RF_ETIMER_START(timer);
    745      1.27     oster #endif
    746      1.24     oster 	rf_FreeAccessStripeMap(asmh);
    747      1.27     oster #if RF_ACC_TRACE > 0
    748       1.6     oster 	RF_ETIMER_STOP(timer);
    749       1.6     oster 	RF_ETIMER_EVAL(timer);
    750       1.6     oster 	tracerec->specific.user.cleanup_us += RF_ETIMER_VAL_US(timer);
    751       1.6     oster 
    752       1.6     oster 	RF_ETIMER_STOP(desc->timer);
    753       1.6     oster 	RF_ETIMER_EVAL(desc->timer);
    754       1.6     oster 
    755       1.6     oster 	timer = desc->tracerec.tot_timer;
    756       1.6     oster 	RF_ETIMER_STOP(timer);
    757       1.6     oster 	RF_ETIMER_EVAL(timer);
    758       1.6     oster 	desc->tracerec.total_us = RF_ETIMER_VAL_US(timer);
    759       1.1     oster 
    760       1.6     oster 	rf_LogTraceRec(raidPtr, tracerec);
    761      1.27     oster #endif
    762       1.6     oster 	desc->flags |= RF_DAG_ACCESS_COMPLETE;
    763       1.1     oster 
    764       1.6     oster 	return RF_FALSE;
    765       1.1     oster }
    766