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rf_states.c revision 1.37
      1  1.37     oster /*	$NetBSD: rf_states.c,v 1.37 2005/01/14 01:33:15 oster 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  1.37     oster __KERNEL_RCSID(0, "$NetBSD: rf_states.c,v 1.37 2005/01/14 01:33:15 oster 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  1.22     oster 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  1.23     oster 		/* after this point, we cannot dereference desc since
    145  1.23     oster 		 * desc may have been freed. desc is only freed in
    146  1.23     oster 		 * LastState, so if we renter this function or loop
    147  1.23     oster 		 * 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  1.22     oster rf_ContinueDagAccess(RF_DagList_t *dagList)
    165   1.6     oster {
    166  1.27     oster #if RF_ACC_TRACE > 0
    167   1.6     oster 	RF_AccTraceEntry_t *tracerec = &(dagList->desc->tracerec);
    168  1.28     oster 	RF_Etimer_t timer;
    169  1.27     oster #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  1.27     oster #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  1.27     oster #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  1.23     oster 		/* when a dag fails, mark desc status as bad and allow
    193  1.23     oster 		 * all other dags in the desc to execute to
    194  1.23     oster 		 * completion.  then, free all dags and start over */
    195   1.6     oster 		desc->status = 1;	/* bad status */
    196  1.25     oster #if 0
    197  1.25     oster 		printf("raid%d: DAG failure: %c addr 0x%lx "
    198  1.25     oster 		       "(%ld) nblk 0x%x (%d) buf 0x%lx state %d\n",
    199  1.23     oster 		       desc->raidPtr->raidid, desc->type,
    200  1.23     oster 		       (long) desc->raidAddress,
    201  1.23     oster 		       (long) desc->raidAddress, (int) desc->numBlocks,
    202  1.23     oster 		       (int) desc->numBlocks,
    203  1.25     oster 		       (unsigned long) (desc->bufPtr), desc->state);
    204  1.25     oster #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  1.22     oster 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  1.22     oster 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  1.22     oster 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  1.22     oster rf_State_Quiesce(RF_RaidAccessDesc_t *desc)
    287   1.6     oster {
    288  1.27     oster #if RF_ACC_TRACE > 0
    289   1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    290   1.6     oster 	RF_Etimer_t timer;
    291  1.27     oster #endif
    292  1.31     oster 	RF_CallbackDesc_t *cb;
    293  1.31     oster 	RF_Raid_t *raidPtr;
    294   1.6     oster 	int     suspended = RF_FALSE;
    295  1.31     oster 	int need_cb, used_cb;
    296   1.6     oster 
    297   1.6     oster 	raidPtr = desc->raidPtr;
    298   1.6     oster 
    299  1.27     oster #if RF_ACC_TRACE > 0
    300   1.6     oster 	RF_ETIMER_START(timer);
    301   1.6     oster 	RF_ETIMER_START(desc->timer);
    302  1.27     oster #endif
    303   1.6     oster 
    304  1.31     oster 	need_cb = 0;
    305  1.31     oster 	used_cb = 0;
    306  1.31     oster 	cb = NULL;
    307  1.31     oster 
    308   1.6     oster 	RF_LOCK_MUTEX(raidPtr->access_suspend_mutex);
    309  1.31     oster 	/* Do an initial check to see if we might need a callback structure */
    310   1.6     oster 	if (raidPtr->accesses_suspended) {
    311  1.31     oster 		need_cb = 1;
    312  1.31     oster 	}
    313  1.31     oster 	RF_UNLOCK_MUTEX(raidPtr->access_suspend_mutex);
    314  1.31     oster 
    315  1.31     oster 	if (need_cb) {
    316  1.31     oster 		/* create a callback if we might need it...
    317  1.31     oster 		   and we likely do. */
    318   1.6     oster 		cb = rf_AllocCallbackDesc();
    319  1.31     oster 	}
    320  1.23     oster 
    321  1.31     oster 	RF_LOCK_MUTEX(raidPtr->access_suspend_mutex);
    322  1.31     oster 	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  1.31     oster 		used_cb = 1;
    329   1.6     oster 	}
    330   1.6     oster 	RF_UNLOCK_MUTEX(raidPtr->access_suspend_mutex);
    331   1.6     oster 
    332  1.31     oster 	if ((need_cb == 1) && (used_cb == 0)) {
    333  1.31     oster 		rf_FreeCallbackDesc(cb);
    334  1.31     oster 	}
    335  1.31     oster 
    336  1.27     oster #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  1.27     oster #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  1.22     oster rf_State_Map(RF_RaidAccessDesc_t *desc)
    352   1.6     oster {
    353   1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    354  1.27     oster #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  1.27     oster #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  1.27     oster #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  1.27     oster #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  1.22     oster rf_State_Lock(RF_RaidAccessDesc_t *desc)
    377   1.6     oster {
    378  1.27     oster #if RF_ACC_TRACE > 0
    379   1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    380  1.28     oster 	RF_Etimer_t timer;
    381  1.27     oster #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  1.32     oster 	RF_StripeNum_t lastStripeID = -1;
    386   1.6     oster 	int     suspended = RF_FALSE;
    387   1.6     oster 
    388  1.27     oster #if RF_ACC_TRACE > 0
    389   1.6     oster 	RF_ETIMER_START(timer);
    390  1.27     oster #endif
    391  1.32     oster 
    392  1.32     oster 	/* acquire each lock that we don't already hold */
    393  1.32     oster 	for (asm_p = asmh->stripeMap; asm_p; asm_p = asm_p->next) {
    394  1.32     oster 		RF_ASSERT(RF_IO_IS_R_OR_W(desc->type));
    395  1.32     oster 		if (!rf_suppressLocksAndLargeWrites &&
    396  1.32     oster 		    asm_p->parityInfo &&
    397  1.32     oster 		    !(desc->flags & RF_DAG_SUPPRESS_LOCKS) &&
    398  1.32     oster 		    !(asm_p->flags & RF_ASM_FLAGS_LOCK_TRIED)) {
    399  1.32     oster 			asm_p->flags |= RF_ASM_FLAGS_LOCK_TRIED;
    400  1.23     oster 				/* locks must be acquired hierarchically */
    401  1.32     oster 			RF_ASSERT(asm_p->stripeID > lastStripeID);
    402  1.32     oster 			lastStripeID = asm_p->stripeID;
    403  1.32     oster 
    404  1.32     oster 			RF_INIT_LOCK_REQ_DESC(asm_p->lockReqDesc, desc->type,
    405  1.32     oster 					      (void (*) (struct buf *)) rf_ContinueRaidAccess, desc, asm_p,
    406  1.32     oster 					      raidPtr->Layout.dataSectorsPerStripe);
    407  1.32     oster 			if (rf_AcquireStripeLock(raidPtr->lockTable, asm_p->stripeID,
    408  1.32     oster 						 &asm_p->lockReqDesc)) {
    409  1.32     oster 				suspended = RF_TRUE;
    410  1.32     oster 				break;
    411  1.32     oster 			}
    412  1.32     oster 		}
    413  1.32     oster 		if (desc->type == RF_IO_TYPE_WRITE &&
    414  1.32     oster 		    raidPtr->status == rf_rs_reconstructing) {
    415  1.32     oster 			if (!(asm_p->flags & RF_ASM_FLAGS_FORCE_TRIED)) {
    416  1.32     oster 				int     val;
    417  1.32     oster 
    418  1.32     oster 				asm_p->flags |= RF_ASM_FLAGS_FORCE_TRIED;
    419  1.32     oster 				val = rf_ForceOrBlockRecon(raidPtr, asm_p,
    420  1.32     oster 							   (void (*) (RF_Raid_t *, void *)) rf_ContinueRaidAccess, desc);
    421  1.32     oster 				if (val == 0) {
    422  1.32     oster 					asm_p->flags |= RF_ASM_FLAGS_RECON_BLOCKED;
    423  1.32     oster 				} else {
    424   1.6     oster 					suspended = RF_TRUE;
    425   1.6     oster 					break;
    426   1.6     oster 				}
    427   1.6     oster 			} else {
    428  1.29     oster #if RF_DEBUG_PSS > 0
    429   1.6     oster 				if (rf_pssDebug) {
    430  1.32     oster 					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  1.29     oster #endif
    435   1.6     oster 			}
    436  1.32     oster 		} else {
    437  1.32     oster #if RF_DEBUG_PSS > 0
    438  1.32     oster 			if (rf_pssDebug) {
    439  1.32     oster 				printf("raid%d: skipping force/block because not write or not under recon, psid %ld\n",
    440  1.32     oster 				       desc->raidPtr->raidid,
    441  1.32     oster 				       (long) asm_p->stripeID);
    442  1.32     oster 			}
    443  1.32     oster #endif
    444   1.6     oster 		}
    445  1.32     oster 	}
    446  1.27     oster #if RF_ACC_TRACE > 0
    447  1.32     oster 	RF_ETIMER_STOP(timer);
    448  1.32     oster 	RF_ETIMER_EVAL(timer);
    449  1.32     oster 	tracerec->specific.user.lock_us += RF_ETIMER_VAL_US(timer);
    450  1.27     oster #endif
    451  1.32     oster 	if (suspended)
    452  1.32     oster 		return (RF_TRUE);
    453  1.32     oster 
    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  1.22     oster rf_State_CreateDAG(RF_RaidAccessDesc_t *desc)
    480   1.1     oster {
    481  1.27     oster #if RF_ACC_TRACE > 0
    482   1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    483   1.6     oster 	RF_Etimer_t timer;
    484  1.27     oster #endif
    485   1.6     oster 	RF_DagHeader_t *dag_h;
    486  1.26     oster 	RF_DagList_t *dagList;
    487  1.25     oster 	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  1.27     oster #if RF_ACC_TRACE > 0
    493   1.6     oster 	RF_ETIMER_START(timer);
    494  1.27     oster #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  1.26     oster 	if (rf_printDAGsDebug) {
    499  1.26     oster 		dagList = desc->dagList;
    500  1.26     oster 		for (i = 0; i < desc->numStripes; i++) {
    501  1.26     oster 			rf_PrintDAGList(dagList.dags);
    502  1.26     oster 			dagList = dagList->next;
    503  1.26     oster 		}
    504  1.26     oster 	}
    505  1.17     oster #endif /* RF_DEBUG_VALIDATE_DAG */
    506  1.27     oster #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  1.27     oster #endif
    512   1.6     oster 
    513   1.6     oster 	desc->status = 0;	/* good status */
    514   1.6     oster 
    515  1.36     oster 	if (selectStatus || (desc->numRetries > RF_RETRY_THRESHOLD)) {
    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  1.36     oster 		if (selectStatus) {
    520  1.36     oster 			printf("raid%d: failed to create a dag. "
    521  1.36     oster 			       "Too many component failures.\n",
    522  1.36     oster 			       desc->raidPtr->raidid);
    523  1.36     oster 		} else {
    524  1.36     oster 			printf("raid%d: IO failed after %d retries.\n",
    525  1.36     oster 			       desc->raidPtr->raidid, RF_RETRY_THRESHOLD);
    526  1.36     oster 		}
    527  1.25     oster 
    528  1.25     oster 		desc->status = 1; /* bad status */
    529  1.25     oster 		/* skip straight to rf_State_Cleanup() */
    530  1.25     oster 		desc->state = rf_CleanupState;
    531  1.25     oster 		bp = (struct buf *)desc->bp;
    532  1.25     oster 		bp->b_flags |= B_ERROR;
    533  1.25     oster 		bp->b_error = EIO;
    534   1.6     oster 	} else {
    535   1.6     oster 		/* bind dags to desc */
    536  1.26     oster 		dagList = desc->dagList;
    537   1.6     oster 		for (i = 0; i < desc->numStripes; i++) {
    538  1.26     oster 			dag_h = dagList->dags;
    539   1.6     oster 			while (dag_h) {
    540   1.6     oster 				dag_h->bp = (struct buf *) desc->bp;
    541  1.27     oster #if RF_ACC_TRACE > 0
    542   1.6     oster 				dag_h->tracerec = tracerec;
    543  1.27     oster #endif
    544   1.6     oster 				dag_h = dag_h->next;
    545   1.6     oster 			}
    546  1.26     oster 			dagList = dagList->next;
    547   1.6     oster 		}
    548   1.6     oster 		desc->flags |= RF_DAG_DISPATCH_RETURNED;
    549   1.6     oster 		desc->state++;	/* next state should be rf_State_ExecuteDAG */
    550   1.6     oster 	}
    551   1.6     oster 	return RF_FALSE;
    552   1.1     oster }
    553   1.1     oster 
    554   1.1     oster 
    555   1.1     oster 
    556  1.26     oster /* the access has an list of dagLists, one dagList per parity stripe.
    557   1.1     oster  * fire the first dag in each parity stripe (dagList).
    558   1.1     oster  * dags within a stripe (dagList) must be executed sequentially
    559   1.1     oster  *  - this preserves atomic parity update
    560   1.1     oster  * dags for independents parity groups (stripes) are fired concurrently */
    561   1.1     oster 
    562   1.6     oster int
    563  1.22     oster rf_State_ExecuteDAG(RF_RaidAccessDesc_t *desc)
    564   1.1     oster {
    565   1.6     oster 	int     i;
    566   1.6     oster 	RF_DagHeader_t *dag_h;
    567  1.26     oster 	RF_DagList_t *dagList;
    568   1.6     oster 
    569  1.23     oster 	/* next state is always rf_State_ProcessDAG important to do
    570  1.23     oster 	 * this before firing the first dag (it may finish before we
    571  1.23     oster 	 * leave this routine) */
    572   1.6     oster 	desc->state++;
    573   1.6     oster 
    574  1.23     oster 	/* sweep dag array, a stripe at a time, firing the first dag
    575  1.23     oster 	 * in each stripe */
    576  1.26     oster 	dagList = desc->dagList;
    577   1.6     oster 	for (i = 0; i < desc->numStripes; i++) {
    578  1.26     oster 		RF_ASSERT(dagList->numDags > 0);
    579  1.26     oster 		RF_ASSERT(dagList->numDagsDone == 0);
    580  1.26     oster 		RF_ASSERT(dagList->numDagsFired == 0);
    581  1.27     oster #if RF_ACC_TRACE > 0
    582  1.26     oster 		RF_ETIMER_START(dagList->tracerec.timer);
    583  1.27     oster #endif
    584   1.6     oster 		/* fire first dag in this stripe */
    585  1.26     oster 		dag_h = dagList->dags;
    586   1.6     oster 		RF_ASSERT(dag_h);
    587  1.26     oster 		dagList->numDagsFired++;
    588  1.26     oster 		rf_DispatchDAG(dag_h, (void (*) (void *)) rf_ContinueDagAccess, dagList);
    589  1.26     oster 		dagList = dagList->next;
    590   1.6     oster 	}
    591   1.6     oster 
    592   1.6     oster 	/* the DAG will always call the callback, even if there was no
    593   1.6     oster 	 * blocking, so we are always suspended in this state */
    594   1.6     oster 	return RF_TRUE;
    595   1.1     oster }
    596   1.1     oster 
    597   1.1     oster 
    598   1.1     oster 
    599   1.1     oster /* rf_State_ProcessDAG is entered when a dag completes.
    600   1.1     oster  * first, check to all dags in the access have completed
    601   1.1     oster  * if not, fire as many dags as possible */
    602   1.1     oster 
    603   1.6     oster int
    604  1.22     oster rf_State_ProcessDAG(RF_RaidAccessDesc_t *desc)
    605   1.1     oster {
    606   1.6     oster 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    607   1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    608   1.6     oster 	RF_DagHeader_t *dag_h;
    609   1.6     oster 	int     i, j, done = RF_TRUE;
    610  1.26     oster 	RF_DagList_t *dagList, *temp;
    611   1.6     oster 
    612   1.6     oster 	/* check to see if this is the last dag */
    613  1.26     oster 	dagList = desc->dagList;
    614  1.26     oster 	for (i = 0; i < desc->numStripes; i++) {
    615  1.26     oster 		if (dagList->numDags != dagList->numDagsDone)
    616   1.6     oster 			done = RF_FALSE;
    617  1.26     oster 		dagList = dagList->next;
    618  1.26     oster 	}
    619   1.6     oster 
    620   1.6     oster 	if (done) {
    621   1.6     oster 		if (desc->status) {
    622   1.6     oster 			/* a dag failed, retry */
    623   1.6     oster 			/* free all dags */
    624  1.26     oster 			dagList = desc->dagList;
    625   1.6     oster 			for (i = 0; i < desc->numStripes; i++) {
    626  1.26     oster 				rf_FreeDAG(dagList->dags);
    627  1.26     oster 				temp = dagList;
    628  1.35     oster 				dagList = dagList->next;
    629  1.34     oster 				rf_FreeDAGList(temp);
    630   1.6     oster 			}
    631  1.37     oster 			desc->dagList = NULL;
    632  1.37     oster 
    633   1.6     oster 			rf_MarkFailuresInASMList(raidPtr, asmh);
    634  1.36     oster 
    635  1.36     oster 			/* note the retry so that we'll bail in
    636  1.36     oster 			   rf_State_CreateDAG() once we've retired
    637  1.36     oster 			   the IO RF_RETRY_THRESHOLD times */
    638  1.36     oster 
    639  1.36     oster 			desc->numRetries++;
    640  1.36     oster 
    641   1.6     oster 			/* back up to rf_State_CreateDAG */
    642   1.6     oster 			desc->state = desc->state - 2;
    643   1.6     oster 			return RF_FALSE;
    644   1.6     oster 		} else {
    645   1.6     oster 			/* move on to rf_State_Cleanup */
    646   1.6     oster 			desc->state++;
    647   1.6     oster 		}
    648   1.6     oster 		return RF_FALSE;
    649   1.6     oster 	} else {
    650   1.6     oster 		/* more dags to execute */
    651   1.6     oster 		/* see if any are ready to be fired.  if so, fire them */
    652   1.6     oster 		/* don't fire the initial dag in a list, it's fired in
    653   1.6     oster 		 * rf_State_ExecuteDAG */
    654  1.26     oster 		dagList = desc->dagList;
    655   1.6     oster 		for (i = 0; i < desc->numStripes; i++) {
    656  1.26     oster 			if ((dagList->numDagsDone < dagList->numDags)
    657  1.26     oster 			    && (dagList->numDagsDone == dagList->numDagsFired)
    658  1.26     oster 			    && (dagList->numDagsFired > 0)) {
    659  1.27     oster #if RF_ACC_TRACE > 0
    660  1.26     oster 				RF_ETIMER_START(dagList->tracerec.timer);
    661  1.27     oster #endif
    662   1.6     oster 				/* fire next dag in this stripe */
    663   1.6     oster 				/* first, skip to next dag awaiting execution */
    664  1.26     oster 				dag_h = dagList->dags;
    665  1.26     oster 				for (j = 0; j < dagList->numDagsDone; j++)
    666   1.6     oster 					dag_h = dag_h->next;
    667  1.26     oster 				dagList->numDagsFired++;
    668   1.6     oster 				rf_DispatchDAG(dag_h, (void (*) (void *)) rf_ContinueDagAccess,
    669  1.26     oster 				    dagList);
    670   1.6     oster 			}
    671  1.26     oster 			dagList = dagList->next;
    672   1.6     oster 		}
    673   1.6     oster 		return RF_TRUE;
    674   1.6     oster 	}
    675   1.1     oster }
    676   1.1     oster /* only make it this far if all dags complete successfully */
    677   1.6     oster int
    678  1.22     oster rf_State_Cleanup(RF_RaidAccessDesc_t *desc)
    679   1.1     oster {
    680  1.27     oster #if RF_ACC_TRACE > 0
    681   1.6     oster 	RF_AccTraceEntry_t *tracerec = &desc->tracerec;
    682  1.28     oster 	RF_Etimer_t timer;
    683  1.27     oster #endif
    684   1.6     oster 	RF_AccessStripeMapHeader_t *asmh = desc->asmap;
    685   1.6     oster 	RF_Raid_t *raidPtr = desc->raidPtr;
    686   1.6     oster 	RF_AccessStripeMap_t *asm_p;
    687  1.26     oster 	RF_DagList_t *dagList;
    688  1.11     oster 	int i;
    689   1.6     oster 
    690   1.6     oster 	desc->state++;
    691   1.6     oster 
    692  1.27     oster #if RF_ACC_TRACE > 0
    693   1.6     oster 	timer = tracerec->timer;
    694   1.6     oster 	RF_ETIMER_STOP(timer);
    695   1.6     oster 	RF_ETIMER_EVAL(timer);
    696   1.6     oster 	tracerec->specific.user.dag_retry_us = RF_ETIMER_VAL_US(timer);
    697   1.6     oster 
    698   1.6     oster 	/* the RAID I/O is complete.  Clean up. */
    699   1.6     oster 	tracerec->specific.user.dag_retry_us = 0;
    700   1.6     oster 
    701   1.6     oster 	RF_ETIMER_START(timer);
    702  1.27     oster #endif
    703  1.24     oster 	/* free all dags */
    704  1.26     oster 	dagList = desc->dagList;
    705  1.24     oster 	for (i = 0; i < desc->numStripes; i++) {
    706  1.26     oster 		rf_FreeDAG(dagList->dags);
    707  1.26     oster 		dagList = dagList->next;
    708   1.6     oster 	}
    709  1.27     oster #if RF_ACC_TRACE > 0
    710   1.6     oster 	RF_ETIMER_STOP(timer);
    711   1.6     oster 	RF_ETIMER_EVAL(timer);
    712   1.6     oster 	tracerec->specific.user.cleanup_us = RF_ETIMER_VAL_US(timer);
    713   1.6     oster 
    714   1.6     oster 	RF_ETIMER_START(timer);
    715  1.27     oster #endif
    716  1.32     oster 	for (asm_p = asmh->stripeMap; asm_p; asm_p = asm_p->next) {
    717  1.32     oster 		if (!rf_suppressLocksAndLargeWrites &&
    718  1.32     oster 		    asm_p->parityInfo &&
    719  1.32     oster 		    !(desc->flags & RF_DAG_SUPPRESS_LOCKS)) {
    720  1.32     oster 			RF_ASSERT_VALID_LOCKREQ(&asm_p->lockReqDesc);
    721  1.32     oster 			rf_ReleaseStripeLock(raidPtr->lockTable,
    722  1.32     oster 					     asm_p->stripeID,
    723  1.32     oster 					     &asm_p->lockReqDesc);
    724  1.32     oster 		}
    725  1.32     oster 		if (asm_p->flags & RF_ASM_FLAGS_RECON_BLOCKED) {
    726  1.32     oster 			rf_UnblockRecon(raidPtr, asm_p);
    727   1.6     oster 		}
    728   1.6     oster 	}
    729  1.27     oster #if RF_ACC_TRACE > 0
    730   1.6     oster 	RF_ETIMER_STOP(timer);
    731   1.6     oster 	RF_ETIMER_EVAL(timer);
    732   1.6     oster 	tracerec->specific.user.lock_us += RF_ETIMER_VAL_US(timer);
    733   1.6     oster 
    734   1.6     oster 	RF_ETIMER_START(timer);
    735  1.27     oster #endif
    736  1.24     oster 	rf_FreeAccessStripeMap(asmh);
    737  1.27     oster #if RF_ACC_TRACE > 0
    738   1.6     oster 	RF_ETIMER_STOP(timer);
    739   1.6     oster 	RF_ETIMER_EVAL(timer);
    740   1.6     oster 	tracerec->specific.user.cleanup_us += RF_ETIMER_VAL_US(timer);
    741   1.6     oster 
    742   1.6     oster 	RF_ETIMER_STOP(desc->timer);
    743   1.6     oster 	RF_ETIMER_EVAL(desc->timer);
    744   1.6     oster 
    745   1.6     oster 	timer = desc->tracerec.tot_timer;
    746   1.6     oster 	RF_ETIMER_STOP(timer);
    747   1.6     oster 	RF_ETIMER_EVAL(timer);
    748   1.6     oster 	desc->tracerec.total_us = RF_ETIMER_VAL_US(timer);
    749   1.1     oster 
    750   1.6     oster 	rf_LogTraceRec(raidPtr, tracerec);
    751  1.27     oster #endif
    752   1.6     oster 	desc->flags |= RF_DAG_ACCESS_COMPLETE;
    753   1.1     oster 
    754   1.6     oster 	return RF_FALSE;
    755   1.1     oster }
    756