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rf_evenodd.c revision 1.4
      1  1.4  oster /*	$NetBSD: rf_evenodd.c,v 1.4 2000/01/07 03:40:59 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: Chang-Ming Wu
      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  1.1  oster 
     29  1.1  oster /*****************************************************************************************
     30  1.1  oster  *
     31  1.1  oster  * rf_evenodd.c -- implements EVENODD array architecture
     32  1.1  oster  *
     33  1.1  oster  ****************************************************************************************/
     34  1.1  oster 
     35  1.1  oster #include "rf_archs.h"
     36  1.1  oster 
     37  1.1  oster #if RF_INCLUDE_EVENODD > 0
     38  1.1  oster 
     39  1.1  oster #include "rf_types.h"
     40  1.1  oster #include "rf_raid.h"
     41  1.1  oster #include "rf_dag.h"
     42  1.1  oster #include "rf_dagffrd.h"
     43  1.1  oster #include "rf_dagffwr.h"
     44  1.1  oster #include "rf_dagdegrd.h"
     45  1.1  oster #include "rf_dagdegwr.h"
     46  1.1  oster #include "rf_dagutils.h"
     47  1.1  oster #include "rf_dagfuncs.h"
     48  1.1  oster #include "rf_etimer.h"
     49  1.1  oster #include "rf_general.h"
     50  1.1  oster #include "rf_evenodd.h"
     51  1.1  oster #include "rf_configure.h"
     52  1.1  oster #include "rf_parityscan.h"
     53  1.1  oster #include "rf_utils.h"
     54  1.1  oster #include "rf_map.h"
     55  1.1  oster #include "rf_pq.h"
     56  1.1  oster #include "rf_mcpair.h"
     57  1.1  oster #include "rf_evenodd.h"
     58  1.1  oster #include "rf_evenodd_dagfuncs.h"
     59  1.1  oster #include "rf_evenodd_dags.h"
     60  1.1  oster #include "rf_engine.h"
     61  1.1  oster 
     62  1.1  oster typedef struct RF_EvenOddConfigInfo_s {
     63  1.2  oster 	RF_RowCol_t **stripeIdentifier;	/* filled in at config time & used by
     64  1.2  oster 					 * IdentifyStripe */
     65  1.2  oster }       RF_EvenOddConfigInfo_t;
     66  1.2  oster 
     67  1.2  oster int
     68  1.2  oster rf_ConfigureEvenOdd(listp, raidPtr, cfgPtr)
     69  1.2  oster 	RF_ShutdownList_t **listp;
     70  1.2  oster 	RF_Raid_t *raidPtr;
     71  1.2  oster 	RF_Config_t *cfgPtr;
     72  1.2  oster {
     73  1.2  oster 	RF_RaidLayout_t *layoutPtr = &raidPtr->Layout;
     74  1.2  oster 	RF_EvenOddConfigInfo_t *info;
     75  1.2  oster 	RF_RowCol_t i, j, startdisk;
     76  1.2  oster 
     77  1.2  oster 	RF_MallocAndAdd(info, sizeof(RF_EvenOddConfigInfo_t), (RF_EvenOddConfigInfo_t *), raidPtr->cleanupList);
     78  1.2  oster 	layoutPtr->layoutSpecificInfo = (void *) info;
     79  1.2  oster 
     80  1.2  oster 	RF_ASSERT(raidPtr->numRow == 1);
     81  1.2  oster 
     82  1.2  oster 	info->stripeIdentifier = rf_make_2d_array(raidPtr->numCol, raidPtr->numCol, raidPtr->cleanupList);
     83  1.2  oster 	startdisk = 0;
     84  1.2  oster 	for (i = 0; i < raidPtr->numCol; i++) {
     85  1.2  oster 		for (j = 0; j < raidPtr->numCol; j++) {
     86  1.2  oster 			info->stripeIdentifier[i][j] = (startdisk + j) % raidPtr->numCol;
     87  1.2  oster 		}
     88  1.2  oster 		if ((startdisk -= 2) < 0)
     89  1.2  oster 			startdisk += raidPtr->numCol;
     90  1.2  oster 	}
     91  1.1  oster 
     92  1.2  oster 	/* fill in the remaining layout parameters */
     93  1.2  oster 	layoutPtr->numStripe = layoutPtr->stripeUnitsPerDisk;
     94  1.2  oster 	layoutPtr->bytesPerStripeUnit = layoutPtr->sectorsPerStripeUnit << raidPtr->logBytesPerSector;
     95  1.2  oster 	layoutPtr->numDataCol = raidPtr->numCol - 2;	/* ORIG:
     96  1.2  oster 							 * layoutPtr->numDataCol
     97  1.2  oster 							 * = raidPtr->numCol-1;  */
     98  1.1  oster #if RF_EO_MATRIX_DIM > 17
     99  1.2  oster 	if (raidPtr->numCol <= 17) {
    100  1.2  oster 		printf("Number of stripe units in a parity stripe is smaller than 17. Please\n");
    101  1.2  oster 		printf("define the macro RF_EO_MATRIX_DIM in file rf_evenodd_dagfuncs.h to \n");
    102  1.2  oster 		printf("be 17 to increase performance. \n");
    103  1.2  oster 		return (EINVAL);
    104  1.2  oster 	}
    105  1.1  oster #elif RF_EO_MATRIX_DIM == 17
    106  1.2  oster 	if (raidPtr->numCol > 17) {
    107  1.2  oster 		printf("Number of stripe units in a parity stripe is bigger than 17. Please\n");
    108  1.2  oster 		printf("define the macro RF_EO_MATRIX_DIM in file rf_evenodd_dagfuncs.h to \n");
    109  1.2  oster 		printf("be 257 for encoding and decoding functions to work. \n");
    110  1.2  oster 		return (EINVAL);
    111  1.2  oster 	}
    112  1.1  oster #endif
    113  1.2  oster 	layoutPtr->dataSectorsPerStripe = layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit;
    114  1.2  oster 	layoutPtr->numParityCol = 2;
    115  1.2  oster 	layoutPtr->dataStripeUnitsPerDisk = layoutPtr->stripeUnitsPerDisk;
    116  1.2  oster 	raidPtr->sectorsPerDisk = layoutPtr->stripeUnitsPerDisk * layoutPtr->sectorsPerStripeUnit;
    117  1.1  oster 
    118  1.2  oster 	raidPtr->totalSectors = layoutPtr->stripeUnitsPerDisk * layoutPtr->numDataCol * layoutPtr->sectorsPerStripeUnit;
    119  1.1  oster 
    120  1.2  oster 	return (0);
    121  1.1  oster }
    122  1.1  oster 
    123  1.2  oster int
    124  1.2  oster rf_GetDefaultNumFloatingReconBuffersEvenOdd(RF_Raid_t * raidPtr)
    125  1.1  oster {
    126  1.2  oster 	return (20);
    127  1.1  oster }
    128  1.1  oster 
    129  1.2  oster RF_HeadSepLimit_t
    130  1.2  oster rf_GetDefaultHeadSepLimitEvenOdd(RF_Raid_t * raidPtr)
    131  1.1  oster {
    132  1.2  oster 	return (10);
    133  1.1  oster }
    134  1.1  oster 
    135  1.2  oster void
    136  1.2  oster rf_IdentifyStripeEvenOdd(
    137  1.2  oster     RF_Raid_t * raidPtr,
    138  1.2  oster     RF_RaidAddr_t addr,
    139  1.2  oster     RF_RowCol_t ** diskids,
    140  1.2  oster     RF_RowCol_t * outRow)
    141  1.1  oster {
    142  1.2  oster 	RF_StripeNum_t stripeID = rf_RaidAddressToStripeID(&raidPtr->Layout, addr);
    143  1.2  oster 	RF_EvenOddConfigInfo_t *info = (RF_EvenOddConfigInfo_t *) raidPtr->Layout.layoutSpecificInfo;
    144  1.1  oster 
    145  1.2  oster 	*outRow = 0;
    146  1.2  oster 	*diskids = info->stripeIdentifier[stripeID % raidPtr->numCol];
    147  1.1  oster }
    148  1.2  oster /* The layout of stripe unit on the disks are:      c0 c1 c2 c3 c4
    149  1.1  oster 
    150  1.1  oster  						     0  1  2  E  P
    151  1.1  oster 						     5  E  P  3  4
    152  1.1  oster 						     P  6  7  8  E
    153  1.1  oster 	 					    10 11  E  P  9
    154  1.1  oster 						     E  P 12 13 14
    155  1.1  oster 						     ....
    156  1.1  oster 
    157  1.2  oster   We use the MapSectorRAID5 to map data information because the routine can be shown to map exactly
    158  1.1  oster   the layout of data stripe unit as shown above although we have 2 redundant information now.
    159  1.1  oster   But for E and P, we use rf_MapEEvenOdd and rf_MapParityEvenOdd which are different method from raid-5.
    160  1.1  oster */
    161  1.1  oster 
    162  1.1  oster 
    163  1.2  oster void
    164  1.2  oster rf_MapParityEvenOdd(
    165  1.2  oster     RF_Raid_t * raidPtr,
    166  1.2  oster     RF_RaidAddr_t raidSector,
    167  1.2  oster     RF_RowCol_t * row,
    168  1.2  oster     RF_RowCol_t * col,
    169  1.2  oster     RF_SectorNum_t * diskSector,
    170  1.2  oster     int remap)
    171  1.1  oster {
    172  1.2  oster 	RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;
    173  1.2  oster 	RF_StripeNum_t endSUIDofthisStrip = (SUID / raidPtr->Layout.numDataCol + 1) * raidPtr->Layout.numDataCol - 1;
    174  1.1  oster 
    175  1.2  oster 	*row = 0;
    176  1.2  oster 	*col = (endSUIDofthisStrip + 2) % raidPtr->numCol;
    177  1.2  oster 	*diskSector = (SUID / (raidPtr->Layout.numDataCol)) * raidPtr->Layout.sectorsPerStripeUnit +
    178  1.2  oster 	    (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
    179  1.1  oster }
    180  1.1  oster 
    181  1.2  oster void
    182  1.2  oster rf_MapEEvenOdd(
    183  1.2  oster     RF_Raid_t * raidPtr,
    184  1.2  oster     RF_RaidAddr_t raidSector,
    185  1.2  oster     RF_RowCol_t * row,
    186  1.2  oster     RF_RowCol_t * col,
    187  1.2  oster     RF_SectorNum_t * diskSector,
    188  1.2  oster     int remap)
    189  1.1  oster {
    190  1.2  oster 	RF_StripeNum_t SUID = raidSector / raidPtr->Layout.sectorsPerStripeUnit;
    191  1.2  oster 	RF_StripeNum_t endSUIDofthisStrip = (SUID / raidPtr->Layout.numDataCol + 1) * raidPtr->Layout.numDataCol - 1;
    192  1.1  oster 
    193  1.2  oster 	*row = 0;
    194  1.2  oster 	*col = (endSUIDofthisStrip + 1) % raidPtr->numCol;
    195  1.2  oster 	*diskSector = (SUID / (raidPtr->Layout.numDataCol)) * raidPtr->Layout.sectorsPerStripeUnit +
    196  1.2  oster 	    (raidSector % raidPtr->Layout.sectorsPerStripeUnit);
    197  1.1  oster }
    198  1.1  oster 
    199  1.2  oster void
    200  1.2  oster rf_EODagSelect(
    201  1.2  oster     RF_Raid_t * raidPtr,
    202  1.2  oster     RF_IoType_t type,
    203  1.2  oster     RF_AccessStripeMap_t * asmap,
    204  1.2  oster     RF_VoidFuncPtr * createFunc)
    205  1.1  oster {
    206  1.2  oster 	RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout);
    207  1.2  oster 	unsigned ndfail = asmap->numDataFailed;
    208  1.2  oster 	unsigned npfail = asmap->numParityFailed + asmap->numQFailed;
    209  1.2  oster 	unsigned ntfail = npfail + ndfail;
    210  1.2  oster 
    211  1.2  oster 	RF_ASSERT(RF_IO_IS_R_OR_W(type));
    212  1.2  oster 	if (ntfail > 2) {
    213  1.2  oster 		RF_ERRORMSG("more than two disks failed in a single group!  Aborting I/O operation.\n");
    214  1.2  oster 		 /* *infoFunc = */ *createFunc = NULL;
    215  1.2  oster 		return;
    216  1.2  oster 	}
    217  1.2  oster 	/* ok, we can do this I/O */
    218  1.2  oster 	if (type == RF_IO_TYPE_READ) {
    219  1.2  oster 		switch (ndfail) {
    220  1.2  oster 		case 0:
    221  1.2  oster 			/* fault free read */
    222  1.2  oster 			*createFunc = (RF_VoidFuncPtr) rf_CreateFaultFreeReadDAG;	/* same as raid 5 */
    223  1.2  oster 			break;
    224  1.2  oster 		case 1:
    225  1.2  oster 			/* lost a single data unit */
    226  1.2  oster 			/* two cases: (1) parity is not lost. do a normal raid
    227  1.2  oster 			 * 5 reconstruct read. (2) parity is lost. do a
    228  1.2  oster 			 * reconstruct read using "e". */
    229  1.2  oster 			if (ntfail == 2) {	/* also lost redundancy */
    230  1.2  oster 				if (asmap->failedPDAs[1]->type == RF_PDA_TYPE_PARITY)
    231  1.2  oster 					*createFunc = (RF_VoidFuncPtr) rf_EO_110_CreateReadDAG;
    232  1.2  oster 				else
    233  1.2  oster 					*createFunc = (RF_VoidFuncPtr) rf_EO_101_CreateReadDAG;
    234  1.2  oster 			} else {
    235  1.2  oster 				/* P and E are ok. But is there a failure in
    236  1.2  oster 				 * some unaccessed data unit? */
    237  1.2  oster 				if (rf_NumFailedDataUnitsInStripe(raidPtr, asmap) == 2)
    238  1.2  oster 					*createFunc = (RF_VoidFuncPtr) rf_EO_200_CreateReadDAG;
    239  1.2  oster 				else
    240  1.2  oster 					*createFunc = (RF_VoidFuncPtr) rf_EO_100_CreateReadDAG;
    241  1.2  oster 			}
    242  1.2  oster 			break;
    243  1.2  oster 		case 2:
    244  1.2  oster 			/* *createFunc = rf_EO_200_CreateReadDAG; */
    245  1.2  oster 			*createFunc = NULL;
    246  1.2  oster 			break;
    247  1.2  oster 		}
    248  1.2  oster 		return;
    249  1.2  oster 	}
    250  1.2  oster 	/* a write */
    251  1.2  oster 	switch (ntfail) {
    252  1.2  oster 	case 0:		/* fault free */
    253  1.2  oster 		if (rf_suppressLocksAndLargeWrites ||
    254  1.2  oster 		    (((asmap->numStripeUnitsAccessed <= (layoutPtr->numDataCol / 2)) && (layoutPtr->numDataCol != 1)) ||
    255  1.2  oster 			(asmap->parityInfo->next != NULL) || (asmap->qInfo->next != NULL) || rf_CheckStripeForFailures(raidPtr, asmap))) {
    256  1.2  oster 
    257  1.2  oster 			*createFunc = (RF_VoidFuncPtr) rf_EOCreateSmallWriteDAG;
    258  1.2  oster 		} else {
    259  1.2  oster 			*createFunc = (RF_VoidFuncPtr) rf_EOCreateLargeWriteDAG;
    260  1.2  oster 		}
    261  1.2  oster 		break;
    262  1.2  oster 
    263  1.2  oster 	case 1:		/* single disk fault */
    264  1.2  oster 		if (npfail == 1) {
    265  1.2  oster 			RF_ASSERT((asmap->failedPDAs[0]->type == RF_PDA_TYPE_PARITY) || (asmap->failedPDAs[0]->type == RF_PDA_TYPE_Q));
    266  1.2  oster 			if (asmap->failedPDAs[0]->type == RF_PDA_TYPE_Q) {	/* q died, treat like
    267  1.2  oster 										 * normal mode raid5
    268  1.2  oster 										 * write. */
    269  1.2  oster 				if (((asmap->numStripeUnitsAccessed <= (layoutPtr->numDataCol / 2)) || (asmap->numStripeUnitsAccessed == 1))
    270  1.2  oster 				    || (asmap->parityInfo->next != NULL) || rf_NumFailedDataUnitsInStripe(raidPtr, asmap))
    271  1.2  oster 					*createFunc = (RF_VoidFuncPtr) rf_EO_001_CreateSmallWriteDAG;
    272  1.2  oster 				else
    273  1.2  oster 					*createFunc = (RF_VoidFuncPtr) rf_EO_001_CreateLargeWriteDAG;
    274  1.2  oster 			} else {/* parity died, small write only updating Q */
    275  1.2  oster 				if (((asmap->numStripeUnitsAccessed <= (layoutPtr->numDataCol / 2)) || (asmap->numStripeUnitsAccessed == 1))
    276  1.2  oster 				    || (asmap->qInfo->next != NULL) || rf_NumFailedDataUnitsInStripe(raidPtr, asmap))
    277  1.2  oster 					*createFunc = (RF_VoidFuncPtr) rf_EO_010_CreateSmallWriteDAG;
    278  1.2  oster 				else
    279  1.2  oster 					*createFunc = (RF_VoidFuncPtr) rf_EO_010_CreateLargeWriteDAG;
    280  1.2  oster 			}
    281  1.2  oster 		} else {	/* data missing. Do a P reconstruct write if
    282  1.2  oster 				 * only a single data unit is lost in the
    283  1.2  oster 				 * stripe, otherwise a reconstruct write which
    284  1.2  oster 				 * employnig both P and E units. */
    285  1.2  oster 			if (rf_NumFailedDataUnitsInStripe(raidPtr, asmap) == 2) {
    286  1.2  oster 				if (asmap->numStripeUnitsAccessed == 1)
    287  1.2  oster 					*createFunc = (RF_VoidFuncPtr) rf_EO_200_CreateWriteDAG;
    288  1.2  oster 				else
    289  1.2  oster 					*createFunc = NULL;	/* No direct support for
    290  1.2  oster 								 * this case now, like
    291  1.2  oster 								 * that in Raid-5  */
    292  1.2  oster 			} else {
    293  1.2  oster 				if (asmap->numStripeUnitsAccessed != 1 && asmap->failedPDAs[0]->numSector != layoutPtr->sectorsPerStripeUnit)
    294  1.2  oster 					*createFunc = NULL;	/* No direct support for
    295  1.2  oster 								 * this case now, like
    296  1.2  oster 								 * that in Raid-5  */
    297  1.2  oster 				else
    298  1.2  oster 					*createFunc = (RF_VoidFuncPtr) rf_EO_100_CreateWriteDAG;
    299  1.2  oster 			}
    300  1.2  oster 		}
    301  1.2  oster 		break;
    302  1.2  oster 
    303  1.2  oster 	case 2:		/* two disk faults */
    304  1.2  oster 		switch (npfail) {
    305  1.2  oster 		case 2:	/* both p and q dead */
    306  1.2  oster 			*createFunc = (RF_VoidFuncPtr) rf_EO_011_CreateWriteDAG;
    307  1.2  oster 			break;
    308  1.2  oster 		case 1:	/* either p or q and dead data */
    309  1.2  oster 			RF_ASSERT(asmap->failedPDAs[0]->type == RF_PDA_TYPE_DATA);
    310  1.2  oster 			RF_ASSERT((asmap->failedPDAs[1]->type == RF_PDA_TYPE_PARITY) || (asmap->failedPDAs[1]->type == RF_PDA_TYPE_Q));
    311  1.2  oster 			if (asmap->failedPDAs[1]->type == RF_PDA_TYPE_Q) {
    312  1.2  oster 				if (asmap->numStripeUnitsAccessed != 1 && asmap->failedPDAs[0]->numSector != layoutPtr->sectorsPerStripeUnit)
    313  1.2  oster 					*createFunc = NULL;	/* In both PQ and
    314  1.2  oster 								 * EvenOdd, no direct
    315  1.2  oster 								 * support for this case
    316  1.2  oster 								 * now, like that in
    317  1.2  oster 								 * Raid-5  */
    318  1.2  oster 				else
    319  1.2  oster 					*createFunc = (RF_VoidFuncPtr) rf_EO_101_CreateWriteDAG;
    320  1.2  oster 			} else {
    321  1.2  oster 				if (asmap->numStripeUnitsAccessed != 1 && asmap->failedPDAs[0]->numSector != layoutPtr->sectorsPerStripeUnit)
    322  1.2  oster 					*createFunc = NULL;	/* No direct support for
    323  1.2  oster 								 * this case, like that
    324  1.2  oster 								 * in Raid-5  */
    325  1.2  oster 				else
    326  1.2  oster 					*createFunc = (RF_VoidFuncPtr) rf_EO_110_CreateWriteDAG;
    327  1.2  oster 			}
    328  1.2  oster 			break;
    329  1.2  oster 		case 0:	/* double data loss */
    330  1.2  oster 			/* if(asmap->failedPDAs[0]->numSector +
    331  1.2  oster 			 * asmap->failedPDAs[1]->numSector == 2 *
    332  1.2  oster 			 * layoutPtr->sectorsPerStripeUnit ) createFunc =
    333  1.2  oster 			 * rf_EOCreateLargeWriteDAG; else    							 */
    334  1.2  oster 			*createFunc = NULL;	/* currently, in Evenodd, No
    335  1.2  oster 						 * support for simultaneous
    336  1.2  oster 						 * access of both failed SUs */
    337  1.2  oster 			break;
    338  1.2  oster 		}
    339  1.2  oster 		break;
    340  1.2  oster 
    341  1.2  oster 	default:		/* more than 2 disk faults */
    342  1.2  oster 		*createFunc = NULL;
    343  1.2  oster 		RF_PANIC();
    344  1.2  oster 	}
    345  1.2  oster 	return;
    346  1.1  oster }
    347  1.1  oster 
    348  1.1  oster 
    349  1.2  oster int
    350  1.2  oster rf_VerifyParityEvenOdd(raidPtr, raidAddr, parityPDA, correct_it, flags)
    351  1.2  oster 	RF_Raid_t *raidPtr;
    352  1.2  oster 	RF_RaidAddr_t raidAddr;
    353  1.2  oster 	RF_PhysDiskAddr_t *parityPDA;
    354  1.2  oster 	int     correct_it;
    355  1.2  oster 	RF_RaidAccessFlags_t flags;
    356  1.1  oster {
    357  1.2  oster 	RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout);
    358  1.2  oster 	RF_RaidAddr_t startAddr = rf_RaidAddressOfPrevStripeBoundary(layoutPtr, raidAddr);
    359  1.2  oster 	RF_SectorCount_t numsector = parityPDA->numSector;
    360  1.2  oster 	int     numbytes = rf_RaidAddressToByte(raidPtr, numsector);
    361  1.2  oster 	int     bytesPerStripe = numbytes * layoutPtr->numDataCol;
    362  1.2  oster 	RF_DagHeader_t *rd_dag_h, *wr_dag_h;	/* read, write dag */
    363  1.2  oster 	RF_DagNode_t *blockNode, *unblockNode, *wrBlock, *wrUnblock;
    364  1.2  oster 	RF_AccessStripeMapHeader_t *asm_h;
    365  1.2  oster 	RF_AccessStripeMap_t *asmap;
    366  1.2  oster 	RF_AllocListElem_t *alloclist;
    367  1.2  oster 	RF_PhysDiskAddr_t *pda;
    368  1.2  oster 	char   *pbuf, *buf, *end_p, *p;
    369  1.2  oster 	char   *redundantbuf2;
    370  1.2  oster 	int     redundantTwoErr = 0, redundantOneErr = 0;
    371  1.2  oster 	int     parity_cant_correct = RF_FALSE, red2_cant_correct = RF_FALSE,
    372  1.2  oster 	        parity_corrected = RF_FALSE, red2_corrected = RF_FALSE;
    373  1.2  oster 	int     i, retcode;
    374  1.2  oster 	RF_ReconUnitNum_t which_ru;
    375  1.2  oster 	RF_StripeNum_t psID = rf_RaidAddressToParityStripeID(layoutPtr, raidAddr, &which_ru);
    376  1.2  oster 	int     stripeWidth = layoutPtr->numDataCol + layoutPtr->numParityCol;
    377  1.2  oster 	RF_AccTraceEntry_t tracerec;
    378  1.2  oster 	RF_MCPair_t *mcpair;
    379  1.2  oster 
    380  1.2  oster 	retcode = RF_PARITY_OKAY;
    381  1.2  oster 
    382  1.2  oster 	mcpair = rf_AllocMCPair();
    383  1.2  oster 	rf_MakeAllocList(alloclist);
    384  1.2  oster 	RF_MallocAndAdd(buf, numbytes * (layoutPtr->numDataCol + layoutPtr->numParityCol), (char *), alloclist);
    385  1.2  oster 	RF_CallocAndAdd(pbuf, 1, numbytes, (char *), alloclist);	/* use calloc to make
    386  1.2  oster 									 * sure buffer is zeroed */
    387  1.2  oster 	end_p = buf + bytesPerStripe;
    388  1.2  oster 	RF_CallocAndAdd(redundantbuf2, 1, numbytes, (char *), alloclist);	/* use calloc to make
    389  1.2  oster 										 * sure buffer is zeroed */
    390  1.2  oster 
    391  1.2  oster 	rd_dag_h = rf_MakeSimpleDAG(raidPtr, stripeWidth, numbytes, buf, rf_DiskReadFunc, rf_DiskReadUndoFunc,
    392  1.2  oster 	    "Rod", alloclist, flags, RF_IO_NORMAL_PRIORITY);
    393  1.2  oster 	blockNode = rd_dag_h->succedents[0];
    394  1.2  oster 	unblockNode = blockNode->succedents[0]->succedents[0];
    395  1.2  oster 
    396  1.2  oster 	/* map the stripe and fill in the PDAs in the dag */
    397  1.2  oster 	asm_h = rf_MapAccess(raidPtr, startAddr, layoutPtr->dataSectorsPerStripe, buf, RF_DONT_REMAP);
    398  1.2  oster 	asmap = asm_h->stripeMap;
    399  1.2  oster 
    400  1.2  oster 	for (pda = asmap->physInfo, i = 0; i < layoutPtr->numDataCol; i++, pda = pda->next) {
    401  1.2  oster 		RF_ASSERT(pda);
    402  1.2  oster 		rf_RangeRestrictPDA(raidPtr, parityPDA, pda, 0, 1);
    403  1.2  oster 		RF_ASSERT(pda->numSector != 0);
    404  1.2  oster 		if (rf_TryToRedirectPDA(raidPtr, pda, 0))
    405  1.2  oster 			goto out;	/* no way to verify parity if disk is
    406  1.2  oster 					 * dead.  return w/ good status */
    407  1.2  oster 		blockNode->succedents[i]->params[0].p = pda;
    408  1.2  oster 		blockNode->succedents[i]->params[2].v = psID;
    409  1.2  oster 		blockNode->succedents[i]->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, 0, 0, which_ru);
    410  1.2  oster 	}
    411  1.2  oster 
    412  1.2  oster 	RF_ASSERT(!asmap->parityInfo->next);
    413  1.2  oster 	rf_RangeRestrictPDA(raidPtr, parityPDA, asmap->parityInfo, 0, 1);
    414  1.2  oster 	RF_ASSERT(asmap->parityInfo->numSector != 0);
    415  1.2  oster 	if (rf_TryToRedirectPDA(raidPtr, asmap->parityInfo, 1))
    416  1.2  oster 		goto out;
    417  1.2  oster 	blockNode->succedents[layoutPtr->numDataCol]->params[0].p = asmap->parityInfo;
    418  1.2  oster 
    419  1.2  oster 	RF_ASSERT(!asmap->qInfo->next);
    420  1.2  oster 	rf_RangeRestrictPDA(raidPtr, parityPDA, asmap->qInfo, 0, 1);
    421  1.2  oster 	RF_ASSERT(asmap->qInfo->numSector != 0);
    422  1.2  oster 	if (rf_TryToRedirectPDA(raidPtr, asmap->qInfo, 1))
    423  1.2  oster 		goto out;
    424  1.2  oster 	/* if disk is dead, b/c no reconstruction is implemented right now,
    425  1.2  oster 	 * the function "rf_TryToRedirectPDA" always return one, which cause
    426  1.2  oster 	 * go to out and return w/ good status   */
    427  1.2  oster 	blockNode->succedents[layoutPtr->numDataCol + 1]->params[0].p = asmap->qInfo;
    428  1.2  oster 
    429  1.2  oster 	/* fire off the DAG */
    430  1.2  oster 	bzero((char *) &tracerec, sizeof(tracerec));
    431  1.2  oster 	rd_dag_h->tracerec = &tracerec;
    432  1.2  oster 
    433  1.2  oster 	if (rf_verifyParityDebug) {
    434  1.2  oster 		printf("Parity verify read dag:\n");
    435  1.2  oster 		rf_PrintDAGList(rd_dag_h);
    436  1.2  oster 	}
    437  1.2  oster 	RF_LOCK_MUTEX(mcpair->mutex);
    438  1.2  oster 	mcpair->flag = 0;
    439  1.2  oster 	rf_DispatchDAG(rd_dag_h, (void (*) (void *)) rf_MCPairWakeupFunc,
    440  1.2  oster 	    (void *) mcpair);
    441  1.2  oster 	while (!mcpair->flag)
    442  1.2  oster 		RF_WAIT_COND(mcpair->cond, mcpair->mutex);
    443  1.2  oster 	RF_UNLOCK_MUTEX(mcpair->mutex);
    444  1.2  oster 	if (rd_dag_h->status != rf_enable) {
    445  1.2  oster 		RF_ERRORMSG("Unable to verify parity:  can't read the stripe\n");
    446  1.2  oster 		retcode = RF_PARITY_COULD_NOT_VERIFY;
    447  1.2  oster 		goto out;
    448  1.2  oster 	}
    449  1.2  oster 	for (p = buf, i = 0; p < end_p; p += numbytes, i++) {
    450  1.2  oster 		rf_e_encToBuf(raidPtr, i, p, RF_EO_MATRIX_DIM - 2, redundantbuf2, numsector);
    451  1.2  oster 		/* the corresponding columes in EvenOdd encoding Matrix for
    452  1.2  oster 		 * these p pointers which point to the databuffer in a full
    453  1.2  oster 		 * stripe are sequentially from 0 to layoutPtr->numDataCol-1 */
    454  1.2  oster 		rf_bxor(p, pbuf, numbytes, NULL);
    455  1.2  oster 	}
    456  1.2  oster 	RF_ASSERT(i == layoutPtr->numDataCol);
    457  1.2  oster 
    458  1.2  oster 	for (i = 0; i < numbytes; i++) {
    459  1.2  oster 		if (pbuf[i] != buf[bytesPerStripe + i]) {
    460  1.2  oster 			if (!correct_it) {
    461  1.2  oster 				RF_ERRORMSG3("Parity verify error: byte %d of parity is 0x%x should be 0x%x\n",
    462  1.2  oster 				    i, (u_char) buf[bytesPerStripe + i], (u_char) pbuf[i]);
    463  1.2  oster 			}
    464  1.2  oster 		}
    465  1.2  oster 		redundantOneErr = 1;
    466  1.2  oster 		break;
    467  1.2  oster 	}
    468  1.2  oster 
    469  1.2  oster 	for (i = 0; i < numbytes; i++) {
    470  1.2  oster 		if (redundantbuf2[i] != buf[bytesPerStripe + numbytes + i]) {
    471  1.2  oster 			if (!correct_it) {
    472  1.2  oster 				RF_ERRORMSG3("Parity verify error: byte %d of second redundant information is 0x%x should be 0x%x\n",
    473  1.2  oster 				    i, (u_char) buf[bytesPerStripe + numbytes + i], (u_char) redundantbuf2[i]);
    474  1.2  oster 			}
    475  1.2  oster 			redundantTwoErr = 1;
    476  1.2  oster 			break;
    477  1.2  oster 		}
    478  1.2  oster 	}
    479  1.2  oster 	if (redundantOneErr || redundantTwoErr)
    480  1.2  oster 		retcode = RF_PARITY_BAD;
    481  1.2  oster 
    482  1.2  oster 	/* correct the first redundant disk, ie parity if it is error    */
    483  1.2  oster 	if (redundantOneErr && correct_it) {
    484  1.2  oster 		wr_dag_h = rf_MakeSimpleDAG(raidPtr, 1, numbytes, pbuf, rf_DiskWriteFunc, rf_DiskWriteUndoFunc,
    485  1.2  oster 		    "Wnp", alloclist, flags, RF_IO_NORMAL_PRIORITY);
    486  1.2  oster 		wrBlock = wr_dag_h->succedents[0];
    487  1.2  oster 		wrUnblock = wrBlock->succedents[0]->succedents[0];
    488  1.2  oster 		wrBlock->succedents[0]->params[0].p = asmap->parityInfo;
    489  1.2  oster 		wrBlock->succedents[0]->params[2].v = psID;
    490  1.2  oster 		wrBlock->succedents[0]->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, 0, 0, which_ru);
    491  1.2  oster 		bzero((char *) &tracerec, sizeof(tracerec));
    492  1.2  oster 		wr_dag_h->tracerec = &tracerec;
    493  1.2  oster 		if (rf_verifyParityDebug) {
    494  1.2  oster 			printf("Parity verify write dag:\n");
    495  1.2  oster 			rf_PrintDAGList(wr_dag_h);
    496  1.2  oster 		}
    497  1.2  oster 		RF_LOCK_MUTEX(mcpair->mutex);
    498  1.2  oster 		mcpair->flag = 0;
    499  1.2  oster 		rf_DispatchDAG(wr_dag_h, (void (*) (void *)) rf_MCPairWakeupFunc,
    500  1.2  oster 		    (void *) mcpair);
    501  1.2  oster 		while (!mcpair->flag)
    502  1.2  oster 			RF_WAIT_COND(mcpair->cond, mcpair->mutex);
    503  1.2  oster 		RF_UNLOCK_MUTEX(mcpair->mutex);
    504  1.2  oster 		if (wr_dag_h->status != rf_enable) {
    505  1.2  oster 			RF_ERRORMSG("Unable to correct parity in VerifyParity:  can't write the stripe\n");
    506  1.2  oster 			parity_cant_correct = RF_TRUE;
    507  1.2  oster 		} else {
    508  1.2  oster 			parity_corrected = RF_TRUE;
    509  1.2  oster 		}
    510  1.2  oster 		rf_FreeDAG(wr_dag_h);
    511  1.2  oster 	}
    512  1.2  oster 	if (redundantTwoErr && correct_it) {
    513  1.2  oster 		wr_dag_h = rf_MakeSimpleDAG(raidPtr, 1, numbytes, redundantbuf2, rf_DiskWriteFunc, rf_DiskWriteUndoFunc,
    514  1.2  oster 		    "Wnred2", alloclist, flags, RF_IO_NORMAL_PRIORITY);
    515  1.2  oster 		wrBlock = wr_dag_h->succedents[0];
    516  1.2  oster 		wrUnblock = wrBlock->succedents[0]->succedents[0];
    517  1.2  oster 		wrBlock->succedents[0]->params[0].p = asmap->qInfo;
    518  1.2  oster 		wrBlock->succedents[0]->params[2].v = psID;
    519  1.2  oster 		wrBlock->succedents[0]->params[3].v = RF_CREATE_PARAM3(RF_IO_NORMAL_PRIORITY, 0, 0, which_ru);
    520  1.2  oster 		bzero((char *) &tracerec, sizeof(tracerec));
    521  1.2  oster 		wr_dag_h->tracerec = &tracerec;
    522  1.2  oster 		if (rf_verifyParityDebug) {
    523  1.2  oster 			printf("Dag of write new second redundant information in parity verify :\n");
    524  1.2  oster 			rf_PrintDAGList(wr_dag_h);
    525  1.2  oster 		}
    526  1.2  oster 		RF_LOCK_MUTEX(mcpair->mutex);
    527  1.2  oster 		mcpair->flag = 0;
    528  1.2  oster 		rf_DispatchDAG(wr_dag_h, (void (*) (void *)) rf_MCPairWakeupFunc,
    529  1.2  oster 		    (void *) mcpair);
    530  1.2  oster 		while (!mcpair->flag)
    531  1.2  oster 			RF_WAIT_COND(mcpair->cond, mcpair->mutex);
    532  1.2  oster 		RF_UNLOCK_MUTEX(mcpair->mutex);
    533  1.2  oster 		if (wr_dag_h->status != rf_enable) {
    534  1.2  oster 			RF_ERRORMSG("Unable to correct second redundant information in VerifyParity:  can't write the stripe\n");
    535  1.2  oster 			red2_cant_correct = RF_TRUE;
    536  1.2  oster 		} else {
    537  1.2  oster 			red2_corrected = RF_TRUE;
    538  1.2  oster 		}
    539  1.2  oster 		rf_FreeDAG(wr_dag_h);
    540  1.2  oster 	}
    541  1.2  oster 	if ((redundantOneErr && parity_cant_correct) ||
    542  1.2  oster 	    (redundantTwoErr && red2_cant_correct))
    543  1.2  oster 		retcode = RF_PARITY_COULD_NOT_CORRECT;
    544  1.2  oster 	if ((retcode = RF_PARITY_BAD) && parity_corrected && red2_corrected)
    545  1.2  oster 		retcode = RF_PARITY_CORRECTED;
    546  1.1  oster 
    547  1.1  oster 
    548  1.1  oster out:
    549  1.2  oster 	rf_FreeAccessStripeMap(asm_h);
    550  1.2  oster 	rf_FreeAllocList(alloclist);
    551  1.2  oster 	rf_FreeDAG(rd_dag_h);
    552  1.2  oster 	rf_FreeMCPair(mcpair);
    553  1.2  oster 	return (retcode);
    554  1.1  oster }
    555  1.2  oster #endif				/* RF_INCLUDE_EVENODD > 0 */
    556