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rf_states.c revision 1.48
      1  1.48       mrg /*	$NetBSD: rf_states.c,v 1.48 2011/05/10 07:04:17 mrg 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  1.48       mrg __KERNEL_RCSID(0, "$NetBSD: rf_states.c,v 1.48 2011/05/10 07:04:17 mrg 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  1.48       mrg 	 * We don't support non-async IO.
    221   1.8     oster 	 */
    222  1.48       mrg 	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   1.8     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  1.46       mrg 	rf_lock_mutex2(desc->raidPtr->iodone_lock);
    239  1.46       mrg 	rf_signal_cond2(desc->raidPtr->iodone_cv);
    240  1.46       mrg 	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  1.47       mrg 	rf_lock_mutex2(raidPtr->access_suspend_mutex);
    270   1.6     oster 	raidPtr->accs_in_flight++;	/* used to detect quiescence */
    271  1.47       mrg 	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  1.47       mrg 	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  1.47       mrg 	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  1.47       mrg 	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  1.47       mrg 	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  1.47       mrg 	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  1.47       mrg 	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