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rf_states.c revision 1.20.6.2
      1  1.20.6.1     skrll /*	$NetBSD: rf_states.c,v 1.20.6.2 2004/09/18 14:50:55 skrll 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  1.20.6.1     skrll __KERNEL_RCSID(0, "$NetBSD: rf_states.c,v 1.20.6.2 2004/09/18 14:50:55 skrll 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       1.1     oster 
     49      1.19     oster #ifndef RF_DEBUG_STATES
     50      1.19     oster #define RF_DEBUG_STATES 0
     51      1.19     oster #endif
     52      1.19     oster 
     53       1.1     oster /* prototypes for some of the available states.
     54       1.1     oster 
     55       1.1     oster    States must:
     56       1.1     oster 
     57       1.1     oster      - not block.
     58       1.1     oster 
     59       1.1     oster      - either schedule rf_ContinueRaidAccess as a callback and return
     60       1.1     oster        RF_TRUE, or complete all of their work and return RF_FALSE.
     61       1.1     oster 
     62       1.1     oster      - increment desc->state when they have finished their work.
     63       1.1     oster */
     64       1.1     oster 
     65      1.19     oster #if RF_DEBUG_STATES
     66       1.6     oster static char *
     67       1.6     oster StateName(RF_AccessState_t state)
     68       1.1     oster {
     69       1.6     oster 	switch (state) {
     70       1.6     oster 		case rf_QuiesceState:return "QuiesceState";
     71       1.6     oster 	case rf_MapState:
     72       1.6     oster 		return "MapState";
     73       1.6     oster 	case rf_LockState:
     74       1.6     oster 		return "LockState";
     75       1.6     oster 	case rf_CreateDAGState:
     76       1.6     oster 		return "CreateDAGState";
     77       1.6     oster 	case rf_ExecuteDAGState:
     78       1.6     oster 		return "ExecuteDAGState";
     79       1.6     oster 	case rf_ProcessDAGState:
     80       1.6     oster 		return "ProcessDAGState";
     81       1.6     oster 	case rf_CleanupState:
     82       1.6     oster 		return "CleanupState";
     83       1.6     oster 	case rf_LastState:
     84       1.6     oster 		return "LastState";
     85       1.6     oster 	case rf_IncrAccessesCountState:
     86       1.6     oster 		return "IncrAccessesCountState";
     87       1.6     oster 	case rf_DecrAccessesCountState:
     88       1.6     oster 		return "DecrAccessesCountState";
     89       1.6     oster 	default:
     90       1.6     oster 		return "!!! UnnamedState !!!";
     91       1.6     oster 	}
     92       1.6     oster }
     93      1.19     oster #endif
     94       1.6     oster 
     95       1.6     oster void
     96  1.20.6.1     skrll rf_ContinueRaidAccess(RF_RaidAccessDesc_t *desc)
     97       1.6     oster {
     98       1.6     oster 	int     suspended = RF_FALSE;
     99       1.6     oster 	int     current_state_index = desc->state;
    100       1.6     oster 	RF_AccessState_t current_state = desc->states[current_state_index];
    101      1.19     oster #if RF_DEBUG_STATES
    102      1.12     oster 	int     unit = desc->raidPtr->raidid;
    103      1.19     oster #endif
    104       1.6     oster 
    105       1.6     oster 	do {
    106       1.6     oster 
    107       1.6     oster 		current_state_index = desc->state;
    108       1.6     oster 		current_state = desc->states[current_state_index];
    109       1.6     oster 
    110       1.6     oster 		switch (current_state) {
    111       1.6     oster 
    112       1.6     oster 		case rf_QuiesceState:
    113       1.6     oster 			suspended = rf_State_Quiesce(desc);
    114       1.6     oster 			break;
    115       1.6     oster 		case rf_IncrAccessesCountState:
    116       1.6     oster 			suspended = rf_State_IncrAccessCount(desc);
    117       1.6     oster 			break;
    118       1.6     oster 		case rf_MapState:
    119       1.6     oster 			suspended = rf_State_Map(desc);
    120       1.6     oster 			break;
    121       1.6     oster 		case rf_LockState:
    122       1.6     oster 			suspended = rf_State_Lock(desc);
    123       1.6     oster 			break;
    124       1.6     oster 		case rf_CreateDAGState:
    125       1.6     oster 			suspended = rf_State_CreateDAG(desc);
    126       1.6     oster 			break;
    127       1.6     oster 		case rf_ExecuteDAGState:
    128       1.6     oster 			suspended = rf_State_ExecuteDAG(desc);
    129       1.6     oster 			break;
    130       1.6     oster 		case rf_ProcessDAGState:
    131       1.6     oster 			suspended = rf_State_ProcessDAG(desc);
    132       1.6     oster 			break;
    133       1.6     oster 		case rf_CleanupState:
    134       1.6     oster 			suspended = rf_State_Cleanup(desc);
    135       1.6     oster 			break;
    136       1.6     oster 		case rf_DecrAccessesCountState:
    137       1.6     oster 			suspended = rf_State_DecrAccessCount(desc);
    138       1.6     oster 			break;
    139       1.6     oster 		case rf_LastState:
    140       1.6     oster 			suspended = rf_State_LastState(desc);
    141       1.6     oster 			break;
    142       1.6     oster 		}
    143       1.6     oster 
    144  1.20.6.1     skrll 		/* after this point, we cannot dereference desc since
    145  1.20.6.1     skrll 		 * desc may have been freed. desc is only freed in
    146  1.20.6.1     skrll 		 * LastState, so if we renter this function or loop
    147  1.20.6.1     skrll 		 * back up, desc should be valid. */
    148       1.6     oster 
    149      1.19     oster #if RF_DEBUG_STATES
    150       1.6     oster 		if (rf_printStatesDebug) {
    151      1.12     oster 			printf("raid%d: State: %-24s StateIndex: %3i desc: 0x%ld %s\n",
    152      1.12     oster 			       unit, StateName(current_state),
    153      1.12     oster 			       current_state_index, (long) desc,
    154      1.12     oster 			       suspended ? "callback scheduled" : "looping");
    155       1.6     oster 		}
    156      1.19     oster #endif
    157       1.6     oster 	} while (!suspended && current_state != rf_LastState);
    158       1.6     oster 
    159       1.6     oster 	return;
    160       1.6     oster }
    161       1.6     oster 
    162       1.6     oster 
    163       1.6     oster void
    164  1.20.6.1     skrll rf_ContinueDagAccess(RF_DagList_t *dagList)
    165       1.6     oster {
    166  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    167       1.6     oster 	RF_AccTraceEntry_t *tracerec = &(dagList->desc->tracerec);
    168  1.20.6.1     skrll 	RF_Etimer_t timer;
    169  1.20.6.1     skrll #endif
    170       1.6     oster 	RF_RaidAccessDesc_t *desc;
    171       1.6     oster 	RF_DagHeader_t *dag_h;
    172       1.6     oster 	int     i;
    173       1.6     oster 
    174       1.6     oster 	desc = dagList->desc;
    175       1.6     oster 
    176  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    177       1.6     oster 	timer = tracerec->timer;
    178       1.6     oster 	RF_ETIMER_STOP(timer);
    179       1.6     oster 	RF_ETIMER_EVAL(timer);
    180       1.6     oster 	tracerec->specific.user.exec_us = RF_ETIMER_VAL_US(timer);
    181       1.6     oster 	RF_ETIMER_START(tracerec->timer);
    182  1.20.6.1     skrll #endif
    183       1.6     oster 
    184       1.6     oster 	/* skip to dag which just finished */
    185       1.6     oster 	dag_h = dagList->dags;
    186       1.6     oster 	for (i = 0; i < dagList->numDagsDone; i++) {
    187       1.6     oster 		dag_h = dag_h->next;
    188       1.6     oster 	}
    189       1.6     oster 
    190       1.6     oster 	/* check to see if retry is required */
    191       1.6     oster 	if (dag_h->status == rf_rollBackward) {
    192  1.20.6.1     skrll 		/* when a dag fails, mark desc status as bad and allow
    193  1.20.6.1     skrll 		 * all other dags in the desc to execute to
    194  1.20.6.1     skrll 		 * completion.  then, free all dags and start over */
    195       1.6     oster 		desc->status = 1;	/* bad status */
    196  1.20.6.1     skrll #if 0
    197  1.20.6.1     skrll 		printf("raid%d: DAG failure: %c addr 0x%lx "
    198  1.20.6.1     skrll 		       "(%ld) nblk 0x%x (%d) buf 0x%lx state %d\n",
    199  1.20.6.1     skrll 		       desc->raidPtr->raidid, desc->type,
    200  1.20.6.1     skrll 		       (long) desc->raidAddress,
    201  1.20.6.1     skrll 		       (long) desc->raidAddress, (int) desc->numBlocks,
    202  1.20.6.1     skrll 		       (int) desc->numBlocks,
    203  1.20.6.1     skrll 		       (unsigned long) (desc->bufPtr), desc->state);
    204  1.20.6.1     skrll #endif
    205       1.6     oster 	}
    206       1.6     oster 	dagList->numDagsDone++;
    207       1.6     oster 	rf_ContinueRaidAccess(desc);
    208       1.6     oster }
    209       1.6     oster 
    210       1.6     oster int
    211  1.20.6.1     skrll rf_State_LastState(RF_RaidAccessDesc_t *desc)
    212       1.1     oster {
    213       1.6     oster 	void    (*callbackFunc) (RF_CBParam_t) = desc->callbackFunc;
    214       1.6     oster 	RF_CBParam_t callbackArg;
    215       1.2  drochner 
    216       1.6     oster 	callbackArg.p = desc->callbackArg;
    217       1.8     oster 
    218       1.8     oster 	/*
    219       1.8     oster 	 * If this is not an async request, wake up the caller
    220       1.8     oster 	 */
    221       1.8     oster 	if (desc->async_flag == 0)
    222       1.8     oster 		wakeup(desc->bp);
    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       1.8     oster 	/*
    231       1.8     oster 	 * Wakeup any requests waiting to go.
    232       1.8     oster 	 */
    233       1.8     oster 
    234       1.8     oster 	RF_LOCK_MUTEX(((RF_Raid_t *) desc->raidPtr)->mutex);
    235       1.8     oster 	((RF_Raid_t *) desc->raidPtr)->openings++;
    236       1.8     oster 	RF_UNLOCK_MUTEX(((RF_Raid_t *) desc->raidPtr)->mutex);
    237      1.10     oster 
    238      1.10     oster 	/* wake up any pending IO */
    239      1.10     oster 	raidstart(((RF_Raid_t *) desc->raidPtr));
    240      1.10     oster 
    241       1.8     oster 	/* printf("Calling biodone on 0x%x\n",desc->bp); */
    242       1.8     oster 	biodone(desc->bp);	/* access came through ioctl */
    243       1.3  explorer 
    244       1.6     oster 	if (callbackFunc)
    245       1.6     oster 		callbackFunc(callbackArg);
    246       1.6     oster 	rf_FreeRaidAccDesc(desc);
    247       1.6     oster 
    248       1.6     oster 	return RF_FALSE;
    249       1.6     oster }
    250       1.6     oster 
    251       1.6     oster int
    252  1.20.6.1     skrll rf_State_IncrAccessCount(RF_RaidAccessDesc_t *desc)
    253       1.6     oster {
    254       1.6     oster 	RF_Raid_t *raidPtr;
    255       1.6     oster 
    256       1.6     oster 	raidPtr = desc->raidPtr;
    257       1.6     oster 	/* Bummer. We have to do this to be 100% safe w.r.t. the increment
    258       1.6     oster 	 * below */
    259       1.6     oster 	RF_LOCK_MUTEX(raidPtr->access_suspend_mutex);
    260       1.6     oster 	raidPtr->accs_in_flight++;	/* used to detect quiescence */
    261       1.6     oster 	RF_UNLOCK_MUTEX(raidPtr->access_suspend_mutex);
    262       1.6     oster 
    263       1.6     oster 	desc->state++;
    264       1.6     oster 	return RF_FALSE;
    265       1.6     oster }
    266       1.6     oster 
    267       1.6     oster int
    268  1.20.6.1     skrll rf_State_DecrAccessCount(RF_RaidAccessDesc_t *desc)
    269       1.6     oster {
    270       1.6     oster 	RF_Raid_t *raidPtr;
    271       1.6     oster 
    272       1.6     oster 	raidPtr = desc->raidPtr;
    273       1.6     oster 
    274       1.6     oster 	RF_LOCK_MUTEX(raidPtr->access_suspend_mutex);
    275       1.6     oster 	raidPtr->accs_in_flight--;
    276       1.6     oster 	if (raidPtr->accesses_suspended && raidPtr->accs_in_flight == 0) {
    277      1.20     oster 		rf_SignalQuiescenceLock(raidPtr);
    278       1.6     oster 	}
    279       1.6     oster 	RF_UNLOCK_MUTEX(raidPtr->access_suspend_mutex);
    280       1.6     oster 
    281       1.6     oster 	desc->state++;
    282       1.6     oster 	return RF_FALSE;
    283       1.6     oster }
    284       1.6     oster 
    285       1.6     oster int
    286  1.20.6.1     skrll rf_State_Quiesce(RF_RaidAccessDesc_t *desc)
    287       1.6     oster {
    288  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    289       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    290       1.6     oster 	RF_Etimer_t timer;
    291  1.20.6.1     skrll #endif
    292  1.20.6.1     skrll 	RF_CallbackDesc_t *cb;
    293       1.6     oster 	RF_Raid_t *raidPtr;
    294  1.20.6.1     skrll 	int     suspended = RF_FALSE;
    295  1.20.6.1     skrll 	int need_cb, used_cb;
    296       1.6     oster 
    297       1.6     oster 	raidPtr = desc->raidPtr;
    298       1.6     oster 
    299  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    300       1.6     oster 	RF_ETIMER_START(timer);
    301       1.6     oster 	RF_ETIMER_START(desc->timer);
    302  1.20.6.1     skrll #endif
    303  1.20.6.1     skrll 
    304  1.20.6.1     skrll 	need_cb = 0;
    305  1.20.6.1     skrll 	used_cb = 0;
    306  1.20.6.1     skrll 	cb = NULL;
    307       1.6     oster 
    308       1.6     oster 	RF_LOCK_MUTEX(raidPtr->access_suspend_mutex);
    309  1.20.6.1     skrll 	/* Do an initial check to see if we might need a callback structure */
    310       1.6     oster 	if (raidPtr->accesses_suspended) {
    311  1.20.6.1     skrll 		need_cb = 1;
    312  1.20.6.1     skrll 	}
    313  1.20.6.1     skrll 	RF_UNLOCK_MUTEX(raidPtr->access_suspend_mutex);
    314  1.20.6.1     skrll 
    315  1.20.6.1     skrll 	if (need_cb) {
    316  1.20.6.1     skrll 		/* create a callback if we might need it...
    317  1.20.6.1     skrll 		   and we likely do. */
    318       1.6     oster 		cb = rf_AllocCallbackDesc();
    319  1.20.6.1     skrll 	}
    320  1.20.6.1     skrll 
    321  1.20.6.1     skrll 	RF_LOCK_MUTEX(raidPtr->access_suspend_mutex);
    322  1.20.6.1     skrll 	if (raidPtr->accesses_suspended) {
    323       1.6     oster 		cb->callbackFunc = (void (*) (RF_CBParam_t)) rf_ContinueRaidAccess;
    324       1.6     oster 		cb->callbackArg.p = (void *) desc;
    325       1.6     oster 		cb->next = raidPtr->quiesce_wait_list;
    326       1.6     oster 		raidPtr->quiesce_wait_list = cb;
    327       1.6     oster 		suspended = RF_TRUE;
    328  1.20.6.1     skrll 		used_cb = 1;
    329       1.6     oster 	}
    330       1.6     oster 	RF_UNLOCK_MUTEX(raidPtr->access_suspend_mutex);
    331       1.6     oster 
    332  1.20.6.1     skrll 	if ((need_cb == 1) && (used_cb == 0)) {
    333  1.20.6.1     skrll 		rf_FreeCallbackDesc(cb);
    334  1.20.6.1     skrll 	}
    335  1.20.6.1     skrll 
    336  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    337       1.6     oster 	RF_ETIMER_STOP(timer);
    338       1.6     oster 	RF_ETIMER_EVAL(timer);
    339       1.6     oster 	tracerec->specific.user.suspend_ovhd_us += RF_ETIMER_VAL_US(timer);
    340  1.20.6.1     skrll #endif
    341       1.6     oster 
    342      1.18     oster #if RF_DEBUG_QUIESCE
    343       1.6     oster 	if (suspended && rf_quiesceDebug)
    344       1.6     oster 		printf("Stalling access due to quiescence lock\n");
    345      1.18     oster #endif
    346       1.6     oster 	desc->state++;
    347       1.6     oster 	return suspended;
    348       1.6     oster }
    349       1.6     oster 
    350       1.6     oster int
    351  1.20.6.1     skrll rf_State_Map(RF_RaidAccessDesc_t *desc)
    352       1.6     oster {
    353       1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    354  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    355       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    356       1.6     oster 	RF_Etimer_t timer;
    357       1.6     oster 
    358       1.6     oster 	RF_ETIMER_START(timer);
    359  1.20.6.1     skrll #endif
    360       1.6     oster 
    361       1.6     oster 	if (!(desc->asmap = rf_MapAccess(raidPtr, desc->raidAddress, desc->numBlocks,
    362       1.6     oster 		    desc->bufPtr, RF_DONT_REMAP)))
    363       1.6     oster 		RF_PANIC();
    364       1.6     oster 
    365  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    366       1.6     oster 	RF_ETIMER_STOP(timer);
    367       1.6     oster 	RF_ETIMER_EVAL(timer);
    368       1.6     oster 	tracerec->specific.user.map_us = RF_ETIMER_VAL_US(timer);
    369  1.20.6.1     skrll #endif
    370       1.6     oster 
    371       1.6     oster 	desc->state++;
    372       1.6     oster 	return RF_FALSE;
    373       1.6     oster }
    374       1.6     oster 
    375       1.6     oster int
    376  1.20.6.1     skrll rf_State_Lock(RF_RaidAccessDesc_t *desc)
    377       1.6     oster {
    378  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    379       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    380  1.20.6.1     skrll 	RF_Etimer_t timer;
    381  1.20.6.1     skrll #endif
    382       1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    383       1.6     oster 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    384       1.6     oster 	RF_AccessStripeMap_t *asm_p;
    385  1.20.6.1     skrll 	RF_StripeNum_t lastStripeID = -1;
    386       1.6     oster 	int     suspended = RF_FALSE;
    387       1.6     oster 
    388  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    389       1.6     oster 	RF_ETIMER_START(timer);
    390  1.20.6.1     skrll #endif
    391  1.20.6.1     skrll 
    392  1.20.6.1     skrll 	/* acquire each lock that we don't already hold */
    393  1.20.6.1     skrll 	for (asm_p = asmh->stripeMap; asm_p; asm_p = asm_p->next) {
    394  1.20.6.1     skrll 		RF_ASSERT(RF_IO_IS_R_OR_W(desc->type));
    395  1.20.6.1     skrll 		if (!rf_suppressLocksAndLargeWrites &&
    396  1.20.6.1     skrll 		    asm_p->parityInfo &&
    397  1.20.6.1     skrll 		    !(desc->flags & RF_DAG_SUPPRESS_LOCKS) &&
    398  1.20.6.1     skrll 		    !(asm_p->flags & RF_ASM_FLAGS_LOCK_TRIED)) {
    399  1.20.6.1     skrll 			asm_p->flags |= RF_ASM_FLAGS_LOCK_TRIED;
    400  1.20.6.1     skrll 				/* locks must be acquired hierarchically */
    401  1.20.6.1     skrll 			RF_ASSERT(asm_p->stripeID > lastStripeID);
    402  1.20.6.1     skrll 			lastStripeID = asm_p->stripeID;
    403  1.20.6.1     skrll 
    404  1.20.6.1     skrll 			RF_INIT_LOCK_REQ_DESC(asm_p->lockReqDesc, desc->type,
    405  1.20.6.1     skrll 					      (void (*) (struct buf *)) rf_ContinueRaidAccess, desc, asm_p,
    406  1.20.6.1     skrll 					      raidPtr->Layout.dataSectorsPerStripe);
    407  1.20.6.1     skrll 			if (rf_AcquireStripeLock(raidPtr->lockTable, asm_p->stripeID,
    408  1.20.6.1     skrll 						 &asm_p->lockReqDesc)) {
    409  1.20.6.1     skrll 				suspended = RF_TRUE;
    410  1.20.6.1     skrll 				break;
    411       1.6     oster 			}
    412  1.20.6.1     skrll 		}
    413  1.20.6.1     skrll 		if (desc->type == RF_IO_TYPE_WRITE &&
    414  1.20.6.1     skrll 		    raidPtr->status == rf_rs_reconstructing) {
    415  1.20.6.1     skrll 			if (!(asm_p->flags & RF_ASM_FLAGS_FORCE_TRIED)) {
    416  1.20.6.1     skrll 				int     val;
    417  1.20.6.1     skrll 
    418  1.20.6.1     skrll 				asm_p->flags |= RF_ASM_FLAGS_FORCE_TRIED;
    419  1.20.6.1     skrll 				val = rf_ForceOrBlockRecon(raidPtr, asm_p,
    420  1.20.6.1     skrll 							   (void (*) (RF_Raid_t *, void *)) rf_ContinueRaidAccess, desc);
    421  1.20.6.1     skrll 				if (val == 0) {
    422  1.20.6.1     skrll 					asm_p->flags |= RF_ASM_FLAGS_RECON_BLOCKED;
    423       1.6     oster 				} else {
    424  1.20.6.1     skrll 					suspended = RF_TRUE;
    425  1.20.6.1     skrll 					break;
    426       1.6     oster 				}
    427       1.6     oster 			} else {
    428  1.20.6.1     skrll #if RF_DEBUG_PSS > 0
    429       1.6     oster 				if (rf_pssDebug) {
    430  1.20.6.1     skrll 					printf("raid%d: skipping force/block because already done, psid %ld\n",
    431      1.13     oster 					       desc->raidPtr->raidid,
    432      1.13     oster 					       (long) asm_p->stripeID);
    433       1.6     oster 				}
    434  1.20.6.1     skrll #endif
    435  1.20.6.1     skrll 			}
    436  1.20.6.1     skrll 		} else {
    437  1.20.6.1     skrll #if RF_DEBUG_PSS > 0
    438  1.20.6.1     skrll 			if (rf_pssDebug) {
    439  1.20.6.1     skrll 				printf("raid%d: skipping force/block because not write or not under recon, psid %ld\n",
    440  1.20.6.1     skrll 				       desc->raidPtr->raidid,
    441  1.20.6.1     skrll 				       (long) asm_p->stripeID);
    442       1.6     oster 			}
    443  1.20.6.1     skrll #endif
    444       1.6     oster 		}
    445       1.6     oster 	}
    446  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    447  1.20.6.1     skrll 	RF_ETIMER_STOP(timer);
    448  1.20.6.1     skrll 	RF_ETIMER_EVAL(timer);
    449  1.20.6.1     skrll 	tracerec->specific.user.lock_us += RF_ETIMER_VAL_US(timer);
    450  1.20.6.1     skrll #endif
    451  1.20.6.1     skrll 	if (suspended)
    452  1.20.6.1     skrll 		return (RF_TRUE);
    453  1.20.6.1     skrll 
    454       1.6     oster 	desc->state++;
    455       1.6     oster 	return (RF_FALSE);
    456       1.1     oster }
    457       1.1     oster /*
    458       1.1     oster  * the following three states create, execute, and post-process dags
    459       1.1     oster  * the error recovery unit is a single dag.
    460       1.1     oster  * by default, SelectAlgorithm creates an array of dags, one per parity stripe
    461       1.1     oster  * in some tricky cases, multiple dags per stripe are created
    462       1.1     oster  *   - dags within a parity stripe are executed sequentially (arbitrary order)
    463       1.1     oster  *   - dags for distinct parity stripes are executed concurrently
    464       1.1     oster  *
    465       1.1     oster  * repeat until all dags complete successfully -or- dag selection fails
    466       1.1     oster  *
    467       1.1     oster  * while !done
    468       1.1     oster  *   create dag(s) (SelectAlgorithm)
    469       1.1     oster  *   if dag
    470       1.1     oster  *     execute dag (DispatchDAG)
    471       1.1     oster  *     if dag successful
    472       1.1     oster  *       done (SUCCESS)
    473       1.1     oster  *     else
    474       1.1     oster  *       !done (RETRY - start over with new dags)
    475       1.1     oster  *   else
    476       1.1     oster  *     done (FAIL)
    477       1.1     oster  */
    478       1.6     oster int
    479  1.20.6.1     skrll rf_State_CreateDAG(RF_RaidAccessDesc_t *desc)
    480       1.1     oster {
    481  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    482       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    483       1.6     oster 	RF_Etimer_t timer;
    484  1.20.6.1     skrll #endif
    485       1.6     oster 	RF_DagHeader_t *dag_h;
    486  1.20.6.1     skrll 	RF_DagList_t *dagList;
    487  1.20.6.1     skrll 	struct buf *bp;
    488       1.6     oster 	int     i, selectStatus;
    489       1.6     oster 
    490       1.6     oster 	/* generate a dag for the access, and fire it off.  When the dag
    491       1.6     oster 	 * completes, we'll get re-invoked in the next state. */
    492  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    493       1.6     oster 	RF_ETIMER_START(timer);
    494  1.20.6.1     skrll #endif
    495       1.6     oster 	/* SelectAlgorithm returns one or more dags */
    496       1.6     oster 	selectStatus = rf_SelectAlgorithm(desc, desc->flags | RF_DAG_SUPPRESS_LOCKS);
    497      1.17     oster #if RF_DEBUG_VALIDATE_DAG
    498  1.20.6.1     skrll 	if (rf_printDAGsDebug) {
    499  1.20.6.1     skrll 		dagList = desc->dagList;
    500  1.20.6.1     skrll 		for (i = 0; i < desc->numStripes; i++) {
    501  1.20.6.1     skrll 			rf_PrintDAGList(dagList.dags);
    502  1.20.6.1     skrll 			dagList = dagList->next;
    503  1.20.6.1     skrll 		}
    504  1.20.6.1     skrll 	}
    505      1.17     oster #endif /* RF_DEBUG_VALIDATE_DAG */
    506  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    507       1.6     oster 	RF_ETIMER_STOP(timer);
    508       1.6     oster 	RF_ETIMER_EVAL(timer);
    509       1.6     oster 	/* update time to create all dags */
    510       1.6     oster 	tracerec->specific.user.dag_create_us = RF_ETIMER_VAL_US(timer);
    511  1.20.6.1     skrll #endif
    512       1.6     oster 
    513       1.6     oster 	desc->status = 0;	/* good status */
    514       1.6     oster 
    515       1.6     oster 	if (selectStatus) {
    516       1.6     oster 		/* failed to create a dag */
    517       1.6     oster 		/* this happens when there are too many faults or incomplete
    518       1.6     oster 		 * dag libraries */
    519  1.20.6.1     skrll 		printf("raid%d: failed to create a dag. "
    520  1.20.6.1     skrll 		       "Too many component failures.\n",
    521  1.20.6.1     skrll 		       desc->raidPtr->raidid);
    522  1.20.6.1     skrll 
    523  1.20.6.1     skrll 		desc->status = 1; /* bad status */
    524  1.20.6.1     skrll 		/* skip straight to rf_State_Cleanup() */
    525  1.20.6.1     skrll 		desc->state = rf_CleanupState;
    526  1.20.6.1     skrll 		bp = (struct buf *)desc->bp;
    527  1.20.6.1     skrll 		bp->b_flags |= B_ERROR;
    528  1.20.6.1     skrll 		bp->b_error = EIO;
    529       1.6     oster 	} else {
    530       1.6     oster 		/* bind dags to desc */
    531  1.20.6.1     skrll 		dagList = desc->dagList;
    532       1.6     oster 		for (i = 0; i < desc->numStripes; i++) {
    533  1.20.6.1     skrll 			dag_h = dagList->dags;
    534       1.6     oster 			while (dag_h) {
    535       1.6     oster 				dag_h->bp = (struct buf *) desc->bp;
    536  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    537       1.6     oster 				dag_h->tracerec = tracerec;
    538  1.20.6.1     skrll #endif
    539       1.6     oster 				dag_h = dag_h->next;
    540       1.6     oster 			}
    541  1.20.6.1     skrll 			dagList = dagList->next;
    542       1.6     oster 		}
    543       1.6     oster 		desc->flags |= RF_DAG_DISPATCH_RETURNED;
    544       1.6     oster 		desc->state++;	/* next state should be rf_State_ExecuteDAG */
    545       1.6     oster 	}
    546       1.6     oster 	return RF_FALSE;
    547       1.1     oster }
    548       1.1     oster 
    549       1.1     oster 
    550       1.1     oster 
    551  1.20.6.1     skrll /* the access has an list of dagLists, one dagList per parity stripe.
    552       1.1     oster  * fire the first dag in each parity stripe (dagList).
    553       1.1     oster  * dags within a stripe (dagList) must be executed sequentially
    554       1.1     oster  *  - this preserves atomic parity update
    555       1.1     oster  * dags for independents parity groups (stripes) are fired concurrently */
    556       1.1     oster 
    557       1.6     oster int
    558  1.20.6.1     skrll rf_State_ExecuteDAG(RF_RaidAccessDesc_t *desc)
    559       1.1     oster {
    560       1.6     oster 	int     i;
    561       1.6     oster 	RF_DagHeader_t *dag_h;
    562  1.20.6.1     skrll 	RF_DagList_t *dagList;
    563       1.6     oster 
    564  1.20.6.1     skrll 	/* next state is always rf_State_ProcessDAG important to do
    565  1.20.6.1     skrll 	 * this before firing the first dag (it may finish before we
    566  1.20.6.1     skrll 	 * leave this routine) */
    567       1.6     oster 	desc->state++;
    568       1.6     oster 
    569  1.20.6.1     skrll 	/* sweep dag array, a stripe at a time, firing the first dag
    570  1.20.6.1     skrll 	 * in each stripe */
    571  1.20.6.1     skrll 	dagList = desc->dagList;
    572       1.6     oster 	for (i = 0; i < desc->numStripes; i++) {
    573  1.20.6.1     skrll 		RF_ASSERT(dagList->numDags > 0);
    574  1.20.6.1     skrll 		RF_ASSERT(dagList->numDagsDone == 0);
    575  1.20.6.1     skrll 		RF_ASSERT(dagList->numDagsFired == 0);
    576  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    577  1.20.6.1     skrll 		RF_ETIMER_START(dagList->tracerec.timer);
    578  1.20.6.1     skrll #endif
    579       1.6     oster 		/* fire first dag in this stripe */
    580  1.20.6.1     skrll 		dag_h = dagList->dags;
    581       1.6     oster 		RF_ASSERT(dag_h);
    582  1.20.6.1     skrll 		dagList->numDagsFired++;
    583  1.20.6.1     skrll 		rf_DispatchDAG(dag_h, (void (*) (void *)) rf_ContinueDagAccess, dagList);
    584  1.20.6.1     skrll 		dagList = dagList->next;
    585       1.6     oster 	}
    586       1.6     oster 
    587       1.6     oster 	/* the DAG will always call the callback, even if there was no
    588       1.6     oster 	 * blocking, so we are always suspended in this state */
    589       1.6     oster 	return RF_TRUE;
    590       1.1     oster }
    591       1.1     oster 
    592       1.1     oster 
    593       1.1     oster 
    594       1.1     oster /* rf_State_ProcessDAG is entered when a dag completes.
    595       1.1     oster  * first, check to all dags in the access have completed
    596       1.1     oster  * if not, fire as many dags as possible */
    597       1.1     oster 
    598       1.6     oster int
    599  1.20.6.1     skrll rf_State_ProcessDAG(RF_RaidAccessDesc_t *desc)
    600       1.1     oster {
    601       1.6     oster 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    602       1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    603       1.6     oster 	RF_DagHeader_t *dag_h;
    604       1.6     oster 	int     i, j, done = RF_TRUE;
    605  1.20.6.1     skrll 	RF_DagList_t *dagList, *temp;
    606       1.6     oster 
    607       1.6     oster 	/* check to see if this is the last dag */
    608  1.20.6.1     skrll 	dagList = desc->dagList;
    609  1.20.6.1     skrll 	for (i = 0; i < desc->numStripes; i++) {
    610  1.20.6.1     skrll 		if (dagList->numDags != dagList->numDagsDone)
    611       1.6     oster 			done = RF_FALSE;
    612  1.20.6.1     skrll 		dagList = dagList->next;
    613  1.20.6.1     skrll 	}
    614       1.6     oster 
    615       1.6     oster 	if (done) {
    616       1.6     oster 		if (desc->status) {
    617       1.6     oster 			/* a dag failed, retry */
    618       1.6     oster 			/* free all dags */
    619  1.20.6.1     skrll 			dagList = desc->dagList;
    620       1.6     oster 			for (i = 0; i < desc->numStripes; i++) {
    621  1.20.6.1     skrll 				rf_FreeDAG(dagList->dags);
    622  1.20.6.1     skrll 				temp = dagList;
    623  1.20.6.1     skrll 				dagList = dagList->next;
    624  1.20.6.1     skrll 				rf_FreeDAGList(temp);
    625       1.6     oster 			}
    626       1.6     oster 			rf_MarkFailuresInASMList(raidPtr, asmh);
    627       1.6     oster 			/* back up to rf_State_CreateDAG */
    628       1.6     oster 			desc->state = desc->state - 2;
    629       1.6     oster 			return RF_FALSE;
    630       1.6     oster 		} else {
    631       1.6     oster 			/* move on to rf_State_Cleanup */
    632       1.6     oster 			desc->state++;
    633       1.6     oster 		}
    634       1.6     oster 		return RF_FALSE;
    635       1.6     oster 	} else {
    636       1.6     oster 		/* more dags to execute */
    637       1.6     oster 		/* see if any are ready to be fired.  if so, fire them */
    638       1.6     oster 		/* don't fire the initial dag in a list, it's fired in
    639       1.6     oster 		 * rf_State_ExecuteDAG */
    640  1.20.6.1     skrll 		dagList = desc->dagList;
    641       1.6     oster 		for (i = 0; i < desc->numStripes; i++) {
    642  1.20.6.1     skrll 			if ((dagList->numDagsDone < dagList->numDags)
    643  1.20.6.1     skrll 			    && (dagList->numDagsDone == dagList->numDagsFired)
    644  1.20.6.1     skrll 			    && (dagList->numDagsFired > 0)) {
    645  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    646  1.20.6.1     skrll 				RF_ETIMER_START(dagList->tracerec.timer);
    647  1.20.6.1     skrll #endif
    648       1.6     oster 				/* fire next dag in this stripe */
    649       1.6     oster 				/* first, skip to next dag awaiting execution */
    650  1.20.6.1     skrll 				dag_h = dagList->dags;
    651  1.20.6.1     skrll 				for (j = 0; j < dagList->numDagsDone; j++)
    652       1.6     oster 					dag_h = dag_h->next;
    653  1.20.6.1     skrll 				dagList->numDagsFired++;
    654       1.6     oster 				rf_DispatchDAG(dag_h, (void (*) (void *)) rf_ContinueDagAccess,
    655  1.20.6.1     skrll 				    dagList);
    656       1.6     oster 			}
    657  1.20.6.1     skrll 			dagList = dagList->next;
    658       1.6     oster 		}
    659       1.6     oster 		return RF_TRUE;
    660       1.6     oster 	}
    661       1.1     oster }
    662       1.1     oster /* only make it this far if all dags complete successfully */
    663       1.6     oster int
    664  1.20.6.1     skrll rf_State_Cleanup(RF_RaidAccessDesc_t *desc)
    665       1.1     oster {
    666  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    667       1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    668  1.20.6.1     skrll 	RF_Etimer_t timer;
    669  1.20.6.1     skrll #endif
    670       1.6     oster 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    671       1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    672       1.6     oster 	RF_AccessStripeMap_t *asm_p;
    673  1.20.6.1     skrll 	RF_DagList_t *dagList;
    674      1.11     oster 	int i;
    675       1.6     oster 
    676       1.6     oster 	desc->state++;
    677       1.6     oster 
    678  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    679       1.6     oster 	timer = tracerec->timer;
    680       1.6     oster 	RF_ETIMER_STOP(timer);
    681       1.6     oster 	RF_ETIMER_EVAL(timer);
    682       1.6     oster 	tracerec->specific.user.dag_retry_us = RF_ETIMER_VAL_US(timer);
    683       1.6     oster 
    684       1.6     oster 	/* the RAID I/O is complete.  Clean up. */
    685       1.6     oster 	tracerec->specific.user.dag_retry_us = 0;
    686       1.6     oster 
    687       1.6     oster 	RF_ETIMER_START(timer);
    688  1.20.6.1     skrll #endif
    689  1.20.6.1     skrll 	/* free all dags */
    690  1.20.6.1     skrll 	dagList = desc->dagList;
    691  1.20.6.1     skrll 	for (i = 0; i < desc->numStripes; i++) {
    692  1.20.6.1     skrll 		rf_FreeDAG(dagList->dags);
    693  1.20.6.1     skrll 		dagList = dagList->next;
    694       1.6     oster 	}
    695  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    696       1.6     oster 	RF_ETIMER_STOP(timer);
    697       1.6     oster 	RF_ETIMER_EVAL(timer);
    698       1.6     oster 	tracerec->specific.user.cleanup_us = RF_ETIMER_VAL_US(timer);
    699       1.6     oster 
    700       1.6     oster 	RF_ETIMER_START(timer);
    701  1.20.6.1     skrll #endif
    702  1.20.6.1     skrll 	for (asm_p = asmh->stripeMap; asm_p; asm_p = asm_p->next) {
    703  1.20.6.1     skrll 		if (!rf_suppressLocksAndLargeWrites &&
    704  1.20.6.1     skrll 		    asm_p->parityInfo &&
    705  1.20.6.1     skrll 		    !(desc->flags & RF_DAG_SUPPRESS_LOCKS)) {
    706  1.20.6.1     skrll 			RF_ASSERT_VALID_LOCKREQ(&asm_p->lockReqDesc);
    707  1.20.6.1     skrll 			rf_ReleaseStripeLock(raidPtr->lockTable,
    708  1.20.6.1     skrll 					     asm_p->stripeID,
    709  1.20.6.1     skrll 					     &asm_p->lockReqDesc);
    710  1.20.6.1     skrll 		}
    711  1.20.6.1     skrll 		if (asm_p->flags & RF_ASM_FLAGS_RECON_BLOCKED) {
    712  1.20.6.1     skrll 			rf_UnblockRecon(raidPtr, asm_p);
    713       1.6     oster 		}
    714       1.6     oster 	}
    715  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    716       1.6     oster 	RF_ETIMER_STOP(timer);
    717       1.6     oster 	RF_ETIMER_EVAL(timer);
    718       1.6     oster 	tracerec->specific.user.lock_us += RF_ETIMER_VAL_US(timer);
    719       1.6     oster 
    720       1.6     oster 	RF_ETIMER_START(timer);
    721  1.20.6.1     skrll #endif
    722  1.20.6.1     skrll 	rf_FreeAccessStripeMap(asmh);
    723  1.20.6.1     skrll #if RF_ACC_TRACE > 0
    724       1.6     oster 	RF_ETIMER_STOP(timer);
    725       1.6     oster 	RF_ETIMER_EVAL(timer);
    726       1.6     oster 	tracerec->specific.user.cleanup_us += RF_ETIMER_VAL_US(timer);
    727       1.6     oster 
    728       1.6     oster 	RF_ETIMER_STOP(desc->timer);
    729       1.6     oster 	RF_ETIMER_EVAL(desc->timer);
    730       1.6     oster 
    731       1.6     oster 	timer = desc->tracerec.tot_timer;
    732       1.6     oster 	RF_ETIMER_STOP(timer);
    733       1.6     oster 	RF_ETIMER_EVAL(timer);
    734       1.6     oster 	desc->tracerec.total_us = RF_ETIMER_VAL_US(timer);
    735       1.1     oster 
    736       1.6     oster 	rf_LogTraceRec(raidPtr, tracerec);
    737  1.20.6.1     skrll #endif
    738       1.6     oster 	desc->flags |= RF_DAG_ACCESS_COMPLETE;
    739       1.1     oster 
    740       1.6     oster 	return RF_FALSE;
    741       1.1     oster }
    742