1 /* $NetBSD: rf_map.c,v 1.4 1999/08/13 03:41:56 oster Exp $ */ 2 /* 3 * Copyright (c) 1995 Carnegie-Mellon University. 4 * All rights reserved. 5 * 6 * Author: Mark Holland 7 * 8 * Permission to use, copy, modify and distribute this software and 9 * its documentation is hereby granted, provided that both the copyright 10 * notice and this permission notice appear in all copies of the 11 * software, derivative works or modified versions, and any portions 12 * thereof, and that both notices appear in supporting documentation. 13 * 14 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 15 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 16 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 17 * 18 * Carnegie Mellon requests users of this software to return to 19 * 20 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 21 * School of Computer Science 22 * Carnegie Mellon University 23 * Pittsburgh PA 15213-3890 24 * 25 * any improvements or extensions that they make and grant Carnegie the 26 * rights to redistribute these changes. 27 */ 28 29 /************************************************************************** 30 * 31 * map.c -- main code for mapping RAID addresses to physical disk addresses 32 * 33 **************************************************************************/ 34 35 #include "rf_types.h" 36 #include "rf_threadstuff.h" 37 #include "rf_raid.h" 38 #include "rf_general.h" 39 #include "rf_map.h" 40 #include "rf_freelist.h" 41 #include "rf_shutdown.h" 42 43 static void rf_FreePDAList(RF_PhysDiskAddr_t * start, RF_PhysDiskAddr_t * end, int count); 44 static void 45 rf_FreeASMList(RF_AccessStripeMap_t * start, RF_AccessStripeMap_t * end, 46 int count); 47 48 /***************************************************************************************** 49 * 50 * MapAccess -- main 1st order mapping routine. 51 * 52 * Maps an access in the RAID address space to the corresponding set of physical disk 53 * addresses. The result is returned as a list of AccessStripeMap structures, one per 54 * stripe accessed. Each ASM structure contains a pointer to a list of PhysDiskAddr 55 * structures, which describe the physical locations touched by the user access. Note 56 * that this routine returns only static mapping information, i.e. the list of physical 57 * addresses returned does not necessarily identify the set of physical locations that 58 * will actually be read or written. 59 * 60 * The routine also maps the parity. The physical disk location returned always 61 * indicates the entire parity unit, even when only a subset of it is being accessed. 62 * This is because an access that is not stripe unit aligned but that spans a stripe 63 * unit boundary may require access two distinct portions of the parity unit, and we 64 * can't yet tell which portion(s) we'll actually need. We leave it up to the algorithm 65 * selection code to decide what subset of the parity unit to access. 66 * 67 * Note that addresses in the RAID address space must always be maintained as 68 * longs, instead of ints. 69 * 70 * This routine returns NULL if numBlocks is 0 71 * 72 ****************************************************************************************/ 73 74 RF_AccessStripeMapHeader_t * 75 rf_MapAccess(raidPtr, raidAddress, numBlocks, buffer, remap) 76 RF_Raid_t *raidPtr; 77 RF_RaidAddr_t raidAddress; /* starting address in RAID address 78 * space */ 79 RF_SectorCount_t numBlocks; /* number of blocks in RAID address 80 * space to access */ 81 caddr_t buffer; /* buffer to supply/receive data */ 82 int remap; /* 1 => remap addresses to spare space */ 83 { 84 RF_RaidLayout_t *layoutPtr = &(raidPtr->Layout); 85 RF_AccessStripeMapHeader_t *asm_hdr = NULL; 86 RF_AccessStripeMap_t *asm_list = NULL, *asm_p = NULL; 87 int faultsTolerated = layoutPtr->map->faultsTolerated; 88 RF_RaidAddr_t startAddress = raidAddress; /* we'll change 89 * raidAddress along the 90 * way */ 91 RF_RaidAddr_t endAddress = raidAddress + numBlocks; 92 RF_RaidDisk_t **disks = raidPtr->Disks; 93 94 RF_PhysDiskAddr_t *pda_p, *pda_q; 95 RF_StripeCount_t numStripes = 0; 96 RF_RaidAddr_t stripeRealEndAddress, stripeEndAddress, nextStripeUnitAddress; 97 RF_RaidAddr_t startAddrWithinStripe, lastRaidAddr; 98 RF_StripeCount_t totStripes; 99 RF_StripeNum_t stripeID, lastSID, SUID, lastSUID; 100 RF_AccessStripeMap_t *asmList, *t_asm; 101 RF_PhysDiskAddr_t *pdaList, *t_pda; 102 103 /* allocate all the ASMs and PDAs up front */ 104 lastRaidAddr = raidAddress + numBlocks - 1; 105 stripeID = rf_RaidAddressToStripeID(layoutPtr, raidAddress); 106 lastSID = rf_RaidAddressToStripeID(layoutPtr, lastRaidAddr); 107 totStripes = lastSID - stripeID + 1; 108 SUID = rf_RaidAddressToStripeUnitID(layoutPtr, raidAddress); 109 lastSUID = rf_RaidAddressToStripeUnitID(layoutPtr, lastRaidAddr); 110 111 asmList = rf_AllocASMList(totStripes); 112 pdaList = rf_AllocPDAList(lastSUID - SUID + 1 + faultsTolerated * totStripes); /* may also need pda(s) 113 * per stripe for parity */ 114 115 if (raidAddress + numBlocks > raidPtr->totalSectors) { 116 RF_ERRORMSG1("Unable to map access because offset (%d) was invalid\n", 117 (int) raidAddress); 118 return (NULL); 119 } 120 if (rf_mapDebug) 121 rf_PrintRaidAddressInfo(raidPtr, raidAddress, numBlocks); 122 for (; raidAddress < endAddress;) { 123 /* make the next stripe structure */ 124 RF_ASSERT(asmList); 125 t_asm = asmList; 126 asmList = asmList->next; 127 bzero((char *) t_asm, sizeof(RF_AccessStripeMap_t)); 128 if (!asm_p) 129 asm_list = asm_p = t_asm; 130 else { 131 asm_p->next = t_asm; 132 asm_p = asm_p->next; 133 } 134 numStripes++; 135 136 /* map SUs from current location to the end of the stripe */ 137 asm_p->stripeID = /* rf_RaidAddressToStripeID(layoutPtr, 138 raidAddress) */ stripeID++; 139 stripeRealEndAddress = rf_RaidAddressOfNextStripeBoundary(layoutPtr, raidAddress); 140 stripeEndAddress = RF_MIN(endAddress, stripeRealEndAddress); 141 asm_p->raidAddress = raidAddress; 142 asm_p->endRaidAddress = stripeEndAddress; 143 144 /* map each stripe unit in the stripe */ 145 pda_p = NULL; 146 startAddrWithinStripe = raidAddress; /* Raid addr of start of 147 * portion of access 148 * that is within this 149 * stripe */ 150 for (; raidAddress < stripeEndAddress;) { 151 RF_ASSERT(pdaList); 152 t_pda = pdaList; 153 pdaList = pdaList->next; 154 bzero((char *) t_pda, sizeof(RF_PhysDiskAddr_t)); 155 if (!pda_p) 156 asm_p->physInfo = pda_p = t_pda; 157 else { 158 pda_p->next = t_pda; 159 pda_p = pda_p->next; 160 } 161 162 pda_p->type = RF_PDA_TYPE_DATA; 163 (layoutPtr->map->MapSector) (raidPtr, raidAddress, &(pda_p->row), &(pda_p->col), &(pda_p->startSector), remap); 164 165 /* mark any failures we find. failedPDA is don't-care 166 * if there is more than one failure */ 167 pda_p->raidAddress = raidAddress; /* the RAID address 168 * corresponding to this 169 * physical disk address */ 170 nextStripeUnitAddress = rf_RaidAddressOfNextStripeUnitBoundary(layoutPtr, raidAddress); 171 pda_p->numSector = RF_MIN(endAddress, nextStripeUnitAddress) - raidAddress; 172 RF_ASSERT(pda_p->numSector != 0); 173 rf_ASMCheckStatus(raidPtr, pda_p, asm_p, disks, 0); 174 pda_p->bufPtr = buffer + rf_RaidAddressToByte(raidPtr, (raidAddress - startAddress)); 175 asm_p->totalSectorsAccessed += pda_p->numSector; 176 asm_p->numStripeUnitsAccessed++; 177 asm_p->origRow = pda_p->row; /* redundant but 178 * harmless to do this 179 * in every loop 180 * iteration */ 181 182 raidAddress = RF_MIN(endAddress, nextStripeUnitAddress); 183 } 184 185 /* Map the parity. At this stage, the startSector and 186 * numSector fields for the parity unit are always set to 187 * indicate the entire parity unit. We may modify this after 188 * mapping the data portion. */ 189 switch (faultsTolerated) { 190 case 0: 191 break; 192 case 1: /* single fault tolerant */ 193 RF_ASSERT(pdaList); 194 t_pda = pdaList; 195 pdaList = pdaList->next; 196 bzero((char *) t_pda, sizeof(RF_PhysDiskAddr_t)); 197 pda_p = asm_p->parityInfo = t_pda; 198 pda_p->type = RF_PDA_TYPE_PARITY; 199 (layoutPtr->map->MapParity) (raidPtr, rf_RaidAddressOfPrevStripeUnitBoundary(layoutPtr, startAddrWithinStripe), 200 &(pda_p->row), &(pda_p->col), &(pda_p->startSector), remap); 201 pda_p->numSector = layoutPtr->sectorsPerStripeUnit; 202 /* raidAddr may be needed to find unit to redirect to */ 203 pda_p->raidAddress = rf_RaidAddressOfPrevStripeUnitBoundary(layoutPtr, startAddrWithinStripe); 204 rf_ASMCheckStatus(raidPtr, pda_p, asm_p, disks, 1); 205 rf_ASMParityAdjust(asm_p->parityInfo, startAddrWithinStripe, endAddress, layoutPtr, asm_p); 206 207 break; 208 case 2: /* two fault tolerant */ 209 RF_ASSERT(pdaList && pdaList->next); 210 t_pda = pdaList; 211 pdaList = pdaList->next; 212 bzero((char *) t_pda, sizeof(RF_PhysDiskAddr_t)); 213 pda_p = asm_p->parityInfo = t_pda; 214 pda_p->type = RF_PDA_TYPE_PARITY; 215 t_pda = pdaList; 216 pdaList = pdaList->next; 217 bzero((char *) t_pda, sizeof(RF_PhysDiskAddr_t)); 218 pda_q = asm_p->qInfo = t_pda; 219 pda_q->type = RF_PDA_TYPE_Q; 220 (layoutPtr->map->MapParity) (raidPtr, rf_RaidAddressOfPrevStripeUnitBoundary(layoutPtr, startAddrWithinStripe), 221 &(pda_p->row), &(pda_p->col), &(pda_p->startSector), remap); 222 (layoutPtr->map->MapQ) (raidPtr, rf_RaidAddressOfPrevStripeUnitBoundary(layoutPtr, startAddrWithinStripe), 223 &(pda_q->row), &(pda_q->col), &(pda_q->startSector), remap); 224 pda_q->numSector = pda_p->numSector = layoutPtr->sectorsPerStripeUnit; 225 /* raidAddr may be needed to find unit to redirect to */ 226 pda_p->raidAddress = rf_RaidAddressOfPrevStripeUnitBoundary(layoutPtr, startAddrWithinStripe); 227 pda_q->raidAddress = rf_RaidAddressOfPrevStripeUnitBoundary(layoutPtr, startAddrWithinStripe); 228 /* failure mode stuff */ 229 rf_ASMCheckStatus(raidPtr, pda_p, asm_p, disks, 1); 230 rf_ASMCheckStatus(raidPtr, pda_q, asm_p, disks, 1); 231 rf_ASMParityAdjust(asm_p->parityInfo, startAddrWithinStripe, endAddress, layoutPtr, asm_p); 232 rf_ASMParityAdjust(asm_p->qInfo, startAddrWithinStripe, endAddress, layoutPtr, asm_p); 233 break; 234 } 235 } 236 RF_ASSERT(asmList == NULL && pdaList == NULL); 237 /* make the header structure */ 238 asm_hdr = rf_AllocAccessStripeMapHeader(); 239 RF_ASSERT(numStripes == totStripes); 240 asm_hdr->numStripes = numStripes; 241 asm_hdr->stripeMap = asm_list; 242 243 if (rf_mapDebug) 244 rf_PrintAccessStripeMap(asm_hdr); 245 return (asm_hdr); 246 } 247 /***************************************************************************************** 248 * This routine walks through an ASM list and marks the PDAs that have failed. 249 * It's called only when a disk failure causes an in-flight DAG to fail. 250 * The parity may consist of two components, but we want to use only one failedPDA 251 * pointer. Thus we set failedPDA to point to the first parity component, and rely 252 * on the rest of the code to do the right thing with this. 253 ****************************************************************************************/ 254 255 void 256 rf_MarkFailuresInASMList(raidPtr, asm_h) 257 RF_Raid_t *raidPtr; 258 RF_AccessStripeMapHeader_t *asm_h; 259 { 260 RF_RaidDisk_t **disks = raidPtr->Disks; 261 RF_AccessStripeMap_t *asmap; 262 RF_PhysDiskAddr_t *pda; 263 264 for (asmap = asm_h->stripeMap; asmap; asmap = asmap->next) { 265 asmap->numDataFailed = asmap->numParityFailed = asmap->numQFailed = 0; 266 asmap->numFailedPDAs = 0; 267 bzero((char *) asmap->failedPDAs, 268 RF_MAX_FAILED_PDA * sizeof(RF_PhysDiskAddr_t *)); 269 for (pda = asmap->physInfo; pda; pda = pda->next) { 270 if (RF_DEAD_DISK(disks[pda->row][pda->col].status)) { 271 printf("DEAD DISK BOGUSLY DETECTED!!\n"); 272 asmap->numDataFailed++; 273 asmap->failedPDAs[asmap->numFailedPDAs] = pda; 274 asmap->numFailedPDAs++; 275 } 276 } 277 pda = asmap->parityInfo; 278 if (pda && RF_DEAD_DISK(disks[pda->row][pda->col].status)) { 279 asmap->numParityFailed++; 280 asmap->failedPDAs[asmap->numFailedPDAs] = pda; 281 asmap->numFailedPDAs++; 282 } 283 pda = asmap->qInfo; 284 if (pda && RF_DEAD_DISK(disks[pda->row][pda->col].status)) { 285 asmap->numQFailed++; 286 asmap->failedPDAs[asmap->numFailedPDAs] = pda; 287 asmap->numFailedPDAs++; 288 } 289 } 290 } 291 /***************************************************************************************** 292 * 293 * DuplicateASM -- duplicates an ASM and returns the new one 294 * 295 ****************************************************************************************/ 296 RF_AccessStripeMap_t * 297 rf_DuplicateASM(asmap) 298 RF_AccessStripeMap_t *asmap; 299 { 300 RF_AccessStripeMap_t *new_asm; 301 RF_PhysDiskAddr_t *pda, *new_pda, *t_pda; 302 303 new_pda = NULL; 304 new_asm = rf_AllocAccessStripeMapComponent(); 305 bcopy((char *) asmap, (char *) new_asm, sizeof(RF_AccessStripeMap_t)); 306 new_asm->numFailedPDAs = 0; /* ??? */ 307 new_asm->failedPDAs[0] = NULL; 308 new_asm->physInfo = NULL; 309 new_asm->parityInfo = NULL; 310 new_asm->next = NULL; 311 312 for (pda = asmap->physInfo; pda; pda = pda->next) { /* copy the physInfo 313 * list */ 314 t_pda = rf_AllocPhysDiskAddr(); 315 bcopy((char *) pda, (char *) t_pda, sizeof(RF_PhysDiskAddr_t)); 316 t_pda->next = NULL; 317 if (!new_asm->physInfo) { 318 new_asm->physInfo = t_pda; 319 new_pda = t_pda; 320 } else { 321 new_pda->next = t_pda; 322 new_pda = new_pda->next; 323 } 324 if (pda == asmap->failedPDAs[0]) 325 new_asm->failedPDAs[0] = t_pda; 326 } 327 for (pda = asmap->parityInfo; pda; pda = pda->next) { /* copy the parityInfo 328 * list */ 329 t_pda = rf_AllocPhysDiskAddr(); 330 bcopy((char *) pda, (char *) t_pda, sizeof(RF_PhysDiskAddr_t)); 331 t_pda->next = NULL; 332 if (!new_asm->parityInfo) { 333 new_asm->parityInfo = t_pda; 334 new_pda = t_pda; 335 } else { 336 new_pda->next = t_pda; 337 new_pda = new_pda->next; 338 } 339 if (pda == asmap->failedPDAs[0]) 340 new_asm->failedPDAs[0] = t_pda; 341 } 342 return (new_asm); 343 } 344 /***************************************************************************************** 345 * 346 * DuplicatePDA -- duplicates a PDA and returns the new one 347 * 348 ****************************************************************************************/ 349 RF_PhysDiskAddr_t * 350 rf_DuplicatePDA(pda) 351 RF_PhysDiskAddr_t *pda; 352 { 353 RF_PhysDiskAddr_t *new; 354 355 new = rf_AllocPhysDiskAddr(); 356 bcopy((char *) pda, (char *) new, sizeof(RF_PhysDiskAddr_t)); 357 return (new); 358 } 359 /***************************************************************************************** 360 * 361 * routines to allocate and free list elements. All allocation routines zero the 362 * structure before returning it. 363 * 364 * FreePhysDiskAddr is static. It should never be called directly, because 365 * FreeAccessStripeMap takes care of freeing the PhysDiskAddr list. 366 * 367 ****************************************************************************************/ 368 369 static RF_FreeList_t *rf_asmhdr_freelist; 370 #define RF_MAX_FREE_ASMHDR 128 371 #define RF_ASMHDR_INC 16 372 #define RF_ASMHDR_INITIAL 32 373 374 static RF_FreeList_t *rf_asm_freelist; 375 #define RF_MAX_FREE_ASM 192 376 #define RF_ASM_INC 24 377 #define RF_ASM_INITIAL 64 378 379 static RF_FreeList_t *rf_pda_freelist; 380 #define RF_MAX_FREE_PDA 192 381 #define RF_PDA_INC 24 382 #define RF_PDA_INITIAL 64 383 384 /* called at shutdown time. So far, all that is necessary is to release all the free lists */ 385 static void rf_ShutdownMapModule(void *); 386 static void 387 rf_ShutdownMapModule(ignored) 388 void *ignored; 389 { 390 RF_FREELIST_DESTROY(rf_asmhdr_freelist, next, (RF_AccessStripeMapHeader_t *)); 391 RF_FREELIST_DESTROY(rf_pda_freelist, next, (RF_PhysDiskAddr_t *)); 392 RF_FREELIST_DESTROY(rf_asm_freelist, next, (RF_AccessStripeMap_t *)); 393 } 394 395 int 396 rf_ConfigureMapModule(listp) 397 RF_ShutdownList_t **listp; 398 { 399 int rc; 400 401 RF_FREELIST_CREATE(rf_asmhdr_freelist, RF_MAX_FREE_ASMHDR, 402 RF_ASMHDR_INC, sizeof(RF_AccessStripeMapHeader_t)); 403 if (rf_asmhdr_freelist == NULL) { 404 return (ENOMEM); 405 } 406 RF_FREELIST_CREATE(rf_asm_freelist, RF_MAX_FREE_ASM, 407 RF_ASM_INC, sizeof(RF_AccessStripeMap_t)); 408 if (rf_asm_freelist == NULL) { 409 RF_FREELIST_DESTROY(rf_asmhdr_freelist, next, (RF_AccessStripeMapHeader_t *)); 410 return (ENOMEM); 411 } 412 RF_FREELIST_CREATE(rf_pda_freelist, RF_MAX_FREE_PDA, 413 RF_PDA_INC, sizeof(RF_PhysDiskAddr_t)); 414 if (rf_pda_freelist == NULL) { 415 RF_FREELIST_DESTROY(rf_asmhdr_freelist, next, (RF_AccessStripeMapHeader_t *)); 416 RF_FREELIST_DESTROY(rf_pda_freelist, next, (RF_PhysDiskAddr_t *)); 417 return (ENOMEM); 418 } 419 rc = rf_ShutdownCreate(listp, rf_ShutdownMapModule, NULL); 420 if (rc) { 421 RF_ERRORMSG3("Unable to add to shutdown list file %s line %d rc=%d\n", __FILE__, 422 __LINE__, rc); 423 rf_ShutdownMapModule(NULL); 424 return (rc); 425 } 426 RF_FREELIST_PRIME(rf_asmhdr_freelist, RF_ASMHDR_INITIAL, next, 427 (RF_AccessStripeMapHeader_t *)); 428 RF_FREELIST_PRIME(rf_asm_freelist, RF_ASM_INITIAL, next, 429 (RF_AccessStripeMap_t *)); 430 RF_FREELIST_PRIME(rf_pda_freelist, RF_PDA_INITIAL, next, 431 (RF_PhysDiskAddr_t *)); 432 433 return (0); 434 } 435 436 RF_AccessStripeMapHeader_t * 437 rf_AllocAccessStripeMapHeader() 438 { 439 RF_AccessStripeMapHeader_t *p; 440 441 RF_FREELIST_GET(rf_asmhdr_freelist, p, next, (RF_AccessStripeMapHeader_t *)); 442 bzero((char *) p, sizeof(RF_AccessStripeMapHeader_t)); 443 444 return (p); 445 } 446 447 448 void 449 rf_FreeAccessStripeMapHeader(p) 450 RF_AccessStripeMapHeader_t *p; 451 { 452 RF_FREELIST_FREE(rf_asmhdr_freelist, p, next); 453 } 454 455 RF_PhysDiskAddr_t * 456 rf_AllocPhysDiskAddr() 457 { 458 RF_PhysDiskAddr_t *p; 459 460 RF_FREELIST_GET(rf_pda_freelist, p, next, (RF_PhysDiskAddr_t *)); 461 bzero((char *) p, sizeof(RF_PhysDiskAddr_t)); 462 463 return (p); 464 } 465 /* allocates a list of PDAs, locking the free list only once 466 * when we have to call calloc, we do it one component at a time to simplify 467 * the process of freeing the list at program shutdown. This should not be 468 * much of a performance hit, because it should be very infrequently executed. 469 */ 470 RF_PhysDiskAddr_t * 471 rf_AllocPDAList(count) 472 int count; 473 { 474 RF_PhysDiskAddr_t *p = NULL; 475 476 RF_FREELIST_GET_N(rf_pda_freelist, p, next, (RF_PhysDiskAddr_t *), count); 477 return (p); 478 } 479 480 void 481 rf_FreePhysDiskAddr(p) 482 RF_PhysDiskAddr_t *p; 483 { 484 RF_FREELIST_FREE(rf_pda_freelist, p, next); 485 } 486 487 static void 488 rf_FreePDAList(l_start, l_end, count) 489 RF_PhysDiskAddr_t *l_start, *l_end; /* pointers to start and end 490 * of list */ 491 int count; /* number of elements in list */ 492 { 493 RF_FREELIST_FREE_N(rf_pda_freelist, l_start, next, (RF_PhysDiskAddr_t *), count); 494 } 495 496 RF_AccessStripeMap_t * 497 rf_AllocAccessStripeMapComponent() 498 { 499 RF_AccessStripeMap_t *p; 500 501 RF_FREELIST_GET(rf_asm_freelist, p, next, (RF_AccessStripeMap_t *)); 502 bzero((char *) p, sizeof(RF_AccessStripeMap_t)); 503 504 return (p); 505 } 506 /* this is essentially identical to AllocPDAList. I should combine the two. 507 * when we have to call calloc, we do it one component at a time to simplify 508 * the process of freeing the list at program shutdown. This should not be 509 * much of a performance hit, because it should be very infrequently executed. 510 */ 511 RF_AccessStripeMap_t * 512 rf_AllocASMList(count) 513 int count; 514 { 515 RF_AccessStripeMap_t *p = NULL; 516 517 RF_FREELIST_GET_N(rf_asm_freelist, p, next, (RF_AccessStripeMap_t *), count); 518 return (p); 519 } 520 521 void 522 rf_FreeAccessStripeMapComponent(p) 523 RF_AccessStripeMap_t *p; 524 { 525 RF_FREELIST_FREE(rf_asm_freelist, p, next); 526 } 527 528 static void 529 rf_FreeASMList(l_start, l_end, count) 530 RF_AccessStripeMap_t *l_start, *l_end; 531 int count; 532 { 533 RF_FREELIST_FREE_N(rf_asm_freelist, l_start, next, (RF_AccessStripeMap_t *), count); 534 } 535 536 void 537 rf_FreeAccessStripeMap(hdr) 538 RF_AccessStripeMapHeader_t *hdr; 539 { 540 RF_AccessStripeMap_t *p, *pt = NULL; 541 RF_PhysDiskAddr_t *pdp, *trailer, *pdaList = NULL, *pdaEnd = NULL; 542 int count = 0, t, asm_count = 0; 543 544 for (p = hdr->stripeMap; p; p = p->next) { 545 546 /* link the 3 pda lists into the accumulating pda list */ 547 548 if (!pdaList) 549 pdaList = p->qInfo; 550 else 551 pdaEnd->next = p->qInfo; 552 for (trailer = NULL, pdp = p->qInfo; pdp;) { 553 trailer = pdp; 554 pdp = pdp->next; 555 count++; 556 } 557 if (trailer) 558 pdaEnd = trailer; 559 560 if (!pdaList) 561 pdaList = p->parityInfo; 562 else 563 pdaEnd->next = p->parityInfo; 564 for (trailer = NULL, pdp = p->parityInfo; pdp;) { 565 trailer = pdp; 566 pdp = pdp->next; 567 count++; 568 } 569 if (trailer) 570 pdaEnd = trailer; 571 572 if (!pdaList) 573 pdaList = p->physInfo; 574 else 575 pdaEnd->next = p->physInfo; 576 for (trailer = NULL, pdp = p->physInfo; pdp;) { 577 trailer = pdp; 578 pdp = pdp->next; 579 count++; 580 } 581 if (trailer) 582 pdaEnd = trailer; 583 584 pt = p; 585 asm_count++; 586 } 587 588 /* debug only */ 589 for (t = 0, pdp = pdaList; pdp; pdp = pdp->next) 590 t++; 591 RF_ASSERT(t == count); 592 593 if (pdaList) 594 rf_FreePDAList(pdaList, pdaEnd, count); 595 rf_FreeASMList(hdr->stripeMap, pt, asm_count); 596 rf_FreeAccessStripeMapHeader(hdr); 597 } 598 /* We can't use the large write optimization if there are any failures in the stripe. 599 * In the declustered layout, there is no way to immediately determine what disks 600 * constitute a stripe, so we actually have to hunt through the stripe looking for failures. 601 * The reason we map the parity instead of just using asm->parityInfo->col is because 602 * the latter may have been already redirected to a spare drive, which would 603 * mess up the computation of the stripe offset. 604 * 605 * ASSUMES AT MOST ONE FAILURE IN THE STRIPE. 606 */ 607 int 608 rf_CheckStripeForFailures(raidPtr, asmap) 609 RF_Raid_t *raidPtr; 610 RF_AccessStripeMap_t *asmap; 611 { 612 RF_RowCol_t trow, tcol, prow, pcol, *diskids, row, i; 613 RF_RaidLayout_t *layoutPtr = &raidPtr->Layout; 614 RF_StripeCount_t stripeOffset; 615 int numFailures; 616 RF_RaidAddr_t sosAddr; 617 RF_SectorNum_t diskOffset, poffset; 618 RF_RowCol_t testrow; 619 620 /* quick out in the fault-free case. */ 621 RF_LOCK_MUTEX(raidPtr->mutex); 622 numFailures = raidPtr->numFailures; 623 RF_UNLOCK_MUTEX(raidPtr->mutex); 624 if (numFailures == 0) 625 return (0); 626 627 sosAddr = rf_RaidAddressOfPrevStripeBoundary(layoutPtr, asmap->raidAddress); 628 row = asmap->physInfo->row; 629 (layoutPtr->map->IdentifyStripe) (raidPtr, asmap->raidAddress, &diskids, &testrow); 630 (layoutPtr->map->MapParity) (raidPtr, asmap->raidAddress, &prow, &pcol, &poffset, 0); /* get pcol */ 631 632 /* this need not be true if we've redirected the access to a spare in 633 * another row RF_ASSERT(row == testrow); */ 634 stripeOffset = 0; 635 for (i = 0; i < layoutPtr->numDataCol + layoutPtr->numParityCol; i++) { 636 if (diskids[i] != pcol) { 637 if (RF_DEAD_DISK(raidPtr->Disks[testrow][diskids[i]].status)) { 638 if (raidPtr->status[testrow] != rf_rs_reconstructing) 639 return (1); 640 RF_ASSERT(raidPtr->reconControl[testrow]->fcol == diskids[i]); 641 layoutPtr->map->MapSector(raidPtr, 642 sosAddr + stripeOffset * layoutPtr->sectorsPerStripeUnit, 643 &trow, &tcol, &diskOffset, 0); 644 RF_ASSERT((trow == testrow) && (tcol == diskids[i])); 645 if (!rf_CheckRUReconstructed(raidPtr->reconControl[testrow]->reconMap, diskOffset)) 646 return (1); 647 asmap->flags |= RF_ASM_REDIR_LARGE_WRITE; 648 return (0); 649 } 650 stripeOffset++; 651 } 652 } 653 return (0); 654 } 655 /* 656 return the number of failed data units in the stripe. 657 */ 658 659 int 660 rf_NumFailedDataUnitsInStripe(raidPtr, asmap) 661 RF_Raid_t *raidPtr; 662 RF_AccessStripeMap_t *asmap; 663 { 664 RF_RaidLayout_t *layoutPtr = &raidPtr->Layout; 665 RF_RowCol_t trow, tcol, row, i; 666 RF_SectorNum_t diskOffset; 667 RF_RaidAddr_t sosAddr; 668 int numFailures; 669 670 /* quick out in the fault-free case. */ 671 RF_LOCK_MUTEX(raidPtr->mutex); 672 numFailures = raidPtr->numFailures; 673 RF_UNLOCK_MUTEX(raidPtr->mutex); 674 if (numFailures == 0) 675 return (0); 676 numFailures = 0; 677 678 sosAddr = rf_RaidAddressOfPrevStripeBoundary(layoutPtr, asmap->raidAddress); 679 row = asmap->physInfo->row; 680 for (i = 0; i < layoutPtr->numDataCol; i++) { 681 (layoutPtr->map->MapSector) (raidPtr, sosAddr + i * layoutPtr->sectorsPerStripeUnit, 682 &trow, &tcol, &diskOffset, 0); 683 if (RF_DEAD_DISK(raidPtr->Disks[trow][tcol].status)) 684 numFailures++; 685 } 686 687 return numFailures; 688 } 689 690 691 /***************************************************************************************** 692 * 693 * debug routines 694 * 695 ****************************************************************************************/ 696 697 void 698 rf_PrintAccessStripeMap(asm_h) 699 RF_AccessStripeMapHeader_t *asm_h; 700 { 701 rf_PrintFullAccessStripeMap(asm_h, 0); 702 } 703 704 void 705 rf_PrintFullAccessStripeMap(asm_h, prbuf) 706 RF_AccessStripeMapHeader_t *asm_h; 707 int prbuf; /* flag to print buffer pointers */ 708 { 709 int i; 710 RF_AccessStripeMap_t *asmap = asm_h->stripeMap; 711 RF_PhysDiskAddr_t *p; 712 printf("%d stripes total\n", (int) asm_h->numStripes); 713 for (; asmap; asmap = asmap->next) { 714 /* printf("Num failures: %d\n",asmap->numDataFailed); */ 715 /* printf("Num sectors: 716 * %d\n",(int)asmap->totalSectorsAccessed); */ 717 printf("Stripe %d (%d sectors), failures: %d data, %d parity: ", 718 (int) asmap->stripeID, 719 (int) asmap->totalSectorsAccessed, 720 (int) asmap->numDataFailed, 721 (int) asmap->numParityFailed); 722 if (asmap->parityInfo) { 723 printf("Parity [r%d c%d s%d-%d", asmap->parityInfo->row, asmap->parityInfo->col, 724 (int) asmap->parityInfo->startSector, 725 (int) (asmap->parityInfo->startSector + 726 asmap->parityInfo->numSector - 1)); 727 if (prbuf) 728 printf(" b0x%lx", (unsigned long) asmap->parityInfo->bufPtr); 729 if (asmap->parityInfo->next) { 730 printf(", r%d c%d s%d-%d", asmap->parityInfo->next->row, 731 asmap->parityInfo->next->col, 732 (int) asmap->parityInfo->next->startSector, 733 (int) (asmap->parityInfo->next->startSector + 734 asmap->parityInfo->next->numSector - 1)); 735 if (prbuf) 736 printf(" b0x%lx", (unsigned long) asmap->parityInfo->next->bufPtr); 737 RF_ASSERT(asmap->parityInfo->next->next == NULL); 738 } 739 printf("]\n\t"); 740 } 741 for (i = 0, p = asmap->physInfo; p; p = p->next, i++) { 742 printf("SU r%d c%d s%d-%d ", p->row, p->col, (int) p->startSector, 743 (int) (p->startSector + p->numSector - 1)); 744 if (prbuf) 745 printf("b0x%lx ", (unsigned long) p->bufPtr); 746 if (i && !(i & 1)) 747 printf("\n\t"); 748 } 749 printf("\n"); 750 p = asm_h->stripeMap->failedPDAs[0]; 751 if (asm_h->stripeMap->numDataFailed + asm_h->stripeMap->numParityFailed > 1) 752 printf("[multiple failures]\n"); 753 else 754 if (asm_h->stripeMap->numDataFailed + asm_h->stripeMap->numParityFailed > 0) 755 printf("\t[Failed PDA: r%d c%d s%d-%d]\n", p->row, p->col, 756 (int) p->startSector, (int) (p->startSector + p->numSector - 1)); 757 } 758 } 759 760 void 761 rf_PrintRaidAddressInfo(raidPtr, raidAddr, numBlocks) 762 RF_Raid_t *raidPtr; 763 RF_RaidAddr_t raidAddr; 764 RF_SectorCount_t numBlocks; 765 { 766 RF_RaidLayout_t *layoutPtr = &raidPtr->Layout; 767 RF_RaidAddr_t ra, sosAddr = rf_RaidAddressOfPrevStripeBoundary(layoutPtr, raidAddr); 768 769 printf("Raid addrs of SU boundaries from start of stripe to end of access:\n\t"); 770 for (ra = sosAddr; ra <= raidAddr + numBlocks; ra += layoutPtr->sectorsPerStripeUnit) { 771 printf("%d (0x%x), ", (int) ra, (int) ra); 772 } 773 printf("\n"); 774 printf("Offset into stripe unit: %d (0x%x)\n", 775 (int) (raidAddr % layoutPtr->sectorsPerStripeUnit), 776 (int) (raidAddr % layoutPtr->sectorsPerStripeUnit)); 777 } 778 /* 779 given a parity descriptor and the starting address within a stripe, 780 range restrict the parity descriptor to touch only the correct stuff. 781 */ 782 void 783 rf_ASMParityAdjust( 784 RF_PhysDiskAddr_t * toAdjust, 785 RF_StripeNum_t startAddrWithinStripe, 786 RF_SectorNum_t endAddress, 787 RF_RaidLayout_t * layoutPtr, 788 RF_AccessStripeMap_t * asm_p) 789 { 790 RF_PhysDiskAddr_t *new_pda; 791 792 /* when we're accessing only a portion of one stripe unit, we want the 793 * parity descriptor to identify only the chunk of parity associated 794 * with the data. When the access spans exactly one stripe unit 795 * boundary and is less than a stripe unit in size, it uses two 796 * disjoint regions of the parity unit. When an access spans more 797 * than one stripe unit boundary, it uses all of the parity unit. 798 * 799 * To better handle the case where stripe units are small, we may 800 * eventually want to change the 2nd case so that if the SU size is 801 * below some threshold, we just read/write the whole thing instead of 802 * breaking it up into two accesses. */ 803 if (asm_p->numStripeUnitsAccessed == 1) { 804 int x = (startAddrWithinStripe % layoutPtr->sectorsPerStripeUnit); 805 toAdjust->startSector += x; 806 toAdjust->raidAddress += x; 807 toAdjust->numSector = asm_p->physInfo->numSector; 808 RF_ASSERT(toAdjust->numSector != 0); 809 } else 810 if (asm_p->numStripeUnitsAccessed == 2 && asm_p->totalSectorsAccessed < layoutPtr->sectorsPerStripeUnit) { 811 int x = (startAddrWithinStripe % layoutPtr->sectorsPerStripeUnit); 812 813 /* create a second pda and copy the parity map info 814 * into it */ 815 RF_ASSERT(toAdjust->next == NULL); 816 new_pda = toAdjust->next = rf_AllocPhysDiskAddr(); 817 *new_pda = *toAdjust; /* structure assignment */ 818 new_pda->next = NULL; 819 820 /* adjust the start sector & number of blocks for the 821 * first parity pda */ 822 toAdjust->startSector += x; 823 toAdjust->raidAddress += x; 824 toAdjust->numSector = rf_RaidAddressOfNextStripeUnitBoundary(layoutPtr, startAddrWithinStripe) - startAddrWithinStripe; 825 RF_ASSERT(toAdjust->numSector != 0); 826 827 /* adjust the second pda */ 828 new_pda->numSector = endAddress - rf_RaidAddressOfPrevStripeUnitBoundary(layoutPtr, endAddress); 829 /* new_pda->raidAddress = 830 * rf_RaidAddressOfNextStripeUnitBoundary(layoutPtr, 831 * toAdjust->raidAddress); */ 832 RF_ASSERT(new_pda->numSector != 0); 833 } 834 } 835 /* 836 Check if a disk has been spared or failed. If spared, 837 redirect the I/O. 838 If it has been failed, record it in the asm pointer. 839 Fourth arg is whether data or parity. 840 */ 841 void 842 rf_ASMCheckStatus( 843 RF_Raid_t * raidPtr, 844 RF_PhysDiskAddr_t * pda_p, 845 RF_AccessStripeMap_t * asm_p, 846 RF_RaidDisk_t ** disks, 847 int parity) 848 { 849 RF_DiskStatus_t dstatus; 850 RF_RowCol_t frow, fcol; 851 852 dstatus = disks[pda_p->row][pda_p->col].status; 853 854 if (dstatus == rf_ds_spared) { 855 /* if the disk has been spared, redirect access to the spare */ 856 frow = pda_p->row; 857 fcol = pda_p->col; 858 pda_p->row = disks[frow][fcol].spareRow; 859 pda_p->col = disks[frow][fcol].spareCol; 860 } else 861 if (dstatus == rf_ds_dist_spared) { 862 /* ditto if disk has been spared to dist spare space */ 863 RF_RowCol_t or = pda_p->row, oc = pda_p->col; 864 RF_SectorNum_t oo = pda_p->startSector; 865 866 if (pda_p->type == RF_PDA_TYPE_DATA) 867 raidPtr->Layout.map->MapSector(raidPtr, pda_p->raidAddress, &pda_p->row, &pda_p->col, &pda_p->startSector, RF_REMAP); 868 else 869 raidPtr->Layout.map->MapParity(raidPtr, pda_p->raidAddress, &pda_p->row, &pda_p->col, &pda_p->startSector, RF_REMAP); 870 871 if (rf_mapDebug) { 872 printf("Redirected r %d c %d o %d -> r%d c %d o %d\n", or, oc, (int) oo, 873 pda_p->row, pda_p->col, (int) pda_p->startSector); 874 } 875 } else 876 if (RF_DEAD_DISK(dstatus)) { 877 /* if the disk is inaccessible, mark the 878 * failure */ 879 if (parity) 880 asm_p->numParityFailed++; 881 else { 882 asm_p->numDataFailed++; 883 #if 0 884 /* XXX Do we really want this spewing 885 * out on the console? GO */ 886 printf("DATA_FAILED!\n"); 887 #endif 888 } 889 asm_p->failedPDAs[asm_p->numFailedPDAs] = pda_p; 890 asm_p->numFailedPDAs++; 891 #if 0 892 switch (asm_p->numParityFailed + asm_p->numDataFailed) { 893 case 1: 894 asm_p->failedPDAs[0] = pda_p; 895 break; 896 case 2: 897 asm_p->failedPDAs[1] = pda_p; 898 default: 899 break; 900 } 901 #endif 902 } 903 /* the redirected access should never span a stripe unit boundary */ 904 RF_ASSERT(rf_RaidAddressToStripeUnitID(&raidPtr->Layout, pda_p->raidAddress) == 905 rf_RaidAddressToStripeUnitID(&raidPtr->Layout, pda_p->raidAddress + pda_p->numSector - 1)); 906 RF_ASSERT(pda_p->col != -1); 907 } 908