rf_reconstruct.c revision 1.26.2.1 1 /* $NetBSD: rf_reconstruct.c,v 1.26.2.1 2001/02/03 19:12:40 he 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 (at) 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 * rf_reconstruct.c -- code to perform on-line reconstruction
32 *
33 ************************************************************/
34
35 #include "rf_types.h"
36 #include <sys/time.h>
37 #include <sys/buf.h>
38 #include <sys/errno.h>
39
40 #include <sys/types.h>
41 #include <sys/param.h>
42 #include <sys/systm.h>
43 #include <sys/proc.h>
44 #include <sys/ioctl.h>
45 #include <sys/fcntl.h>
46 #include <sys/vnode.h>
47
48
49 #include "rf_raid.h"
50 #include "rf_reconutil.h"
51 #include "rf_revent.h"
52 #include "rf_reconbuffer.h"
53 #include "rf_acctrace.h"
54 #include "rf_etimer.h"
55 #include "rf_dag.h"
56 #include "rf_desc.h"
57 #include "rf_general.h"
58 #include "rf_freelist.h"
59 #include "rf_debugprint.h"
60 #include "rf_driver.h"
61 #include "rf_utils.h"
62 #include "rf_shutdown.h"
63
64 #include "rf_kintf.h"
65
66 /* setting these to -1 causes them to be set to their default values if not set by debug options */
67
68 #define Dprintf(s) if (rf_reconDebug) rf_debug_printf(s,NULL,NULL,NULL,NULL,NULL,NULL,NULL,NULL)
69 #define Dprintf1(s,a) if (rf_reconDebug) rf_debug_printf(s,(void *)((unsigned long)a),NULL,NULL,NULL,NULL,NULL,NULL,NULL)
70 #define Dprintf2(s,a,b) if (rf_reconDebug) rf_debug_printf(s,(void *)((unsigned long)a),(void *)((unsigned long)b),NULL,NULL,NULL,NULL,NULL,NULL)
71 #define Dprintf3(s,a,b,c) if (rf_reconDebug) rf_debug_printf(s,(void *)((unsigned long)a),(void *)((unsigned long)b),(void *)((unsigned long)c),NULL,NULL,NULL,NULL,NULL)
72 #define Dprintf4(s,a,b,c,d) if (rf_reconDebug) rf_debug_printf(s,(void *)((unsigned long)a),(void *)((unsigned long)b),(void *)((unsigned long)c),(void *)((unsigned long)d),NULL,NULL,NULL,NULL)
73 #define Dprintf5(s,a,b,c,d,e) if (rf_reconDebug) rf_debug_printf(s,(void *)((unsigned long)a),(void *)((unsigned long)b),(void *)((unsigned long)c),(void *)((unsigned long)d),(void *)((unsigned long)e),NULL,NULL,NULL)
74 #define Dprintf6(s,a,b,c,d,e,f) if (rf_reconDebug) rf_debug_printf(s,(void *)((unsigned long)a),(void *)((unsigned long)b),(void *)((unsigned long)c),(void *)((unsigned long)d),(void *)((unsigned long)e),(void *)((unsigned long)f),NULL,NULL)
75 #define Dprintf7(s,a,b,c,d,e,f,g) if (rf_reconDebug) rf_debug_printf(s,(void *)((unsigned long)a),(void *)((unsigned long)b),(void *)((unsigned long)c),(void *)((unsigned long)d),(void *)((unsigned long)e),(void *)((unsigned long)f),(void *)((unsigned long)g),NULL)
76
77 #define DDprintf1(s,a) if (rf_reconDebug) rf_debug_printf(s,(void *)((unsigned long)a),NULL,NULL,NULL,NULL,NULL,NULL,NULL)
78 #define DDprintf2(s,a,b) if (rf_reconDebug) rf_debug_printf(s,(void *)((unsigned long)a),(void *)((unsigned long)b),NULL,NULL,NULL,NULL,NULL,NULL)
79
80 static RF_FreeList_t *rf_recond_freelist;
81 #define RF_MAX_FREE_RECOND 4
82 #define RF_RECOND_INC 1
83
84 static RF_RaidReconDesc_t *
85 AllocRaidReconDesc(RF_Raid_t * raidPtr,
86 RF_RowCol_t row, RF_RowCol_t col, RF_RaidDisk_t * spareDiskPtr,
87 int numDisksDone, RF_RowCol_t srow, RF_RowCol_t scol);
88 static void FreeReconDesc(RF_RaidReconDesc_t * reconDesc);
89 static int
90 ProcessReconEvent(RF_Raid_t * raidPtr, RF_RowCol_t frow,
91 RF_ReconEvent_t * event);
92 static int
93 IssueNextReadRequest(RF_Raid_t * raidPtr, RF_RowCol_t row,
94 RF_RowCol_t col);
95 static int TryToRead(RF_Raid_t * raidPtr, RF_RowCol_t row, RF_RowCol_t col);
96 static int
97 ComputePSDiskOffsets(RF_Raid_t * raidPtr, RF_StripeNum_t psid,
98 RF_RowCol_t row, RF_RowCol_t col, RF_SectorNum_t * outDiskOffset,
99 RF_SectorNum_t * outFailedDiskSectorOffset, RF_RowCol_t * spRow,
100 RF_RowCol_t * spCol, RF_SectorNum_t * spOffset);
101 static int IssueNextWriteRequest(RF_Raid_t * raidPtr, RF_RowCol_t row);
102 static int ReconReadDoneProc(void *arg, int status);
103 static int ReconWriteDoneProc(void *arg, int status);
104 static void
105 CheckForNewMinHeadSep(RF_Raid_t * raidPtr, RF_RowCol_t row,
106 RF_HeadSepLimit_t hsCtr);
107 static int
108 CheckHeadSeparation(RF_Raid_t * raidPtr, RF_PerDiskReconCtrl_t * ctrl,
109 RF_RowCol_t row, RF_RowCol_t col, RF_HeadSepLimit_t hsCtr,
110 RF_ReconUnitNum_t which_ru);
111 static int
112 CheckForcedOrBlockedReconstruction(RF_Raid_t * raidPtr,
113 RF_ReconParityStripeStatus_t * pssPtr, RF_PerDiskReconCtrl_t * ctrl,
114 RF_RowCol_t row, RF_RowCol_t col, RF_StripeNum_t psid,
115 RF_ReconUnitNum_t which_ru);
116 static void ForceReconReadDoneProc(void *arg, int status);
117
118 static void rf_ShutdownReconstruction(void *);
119
120 struct RF_ReconDoneProc_s {
121 void (*proc) (RF_Raid_t *, void *);
122 void *arg;
123 RF_ReconDoneProc_t *next;
124 };
125
126 static RF_FreeList_t *rf_rdp_freelist;
127 #define RF_MAX_FREE_RDP 4
128 #define RF_RDP_INC 1
129
130 static void
131 SignalReconDone(RF_Raid_t * raidPtr)
132 {
133 RF_ReconDoneProc_t *p;
134
135 RF_LOCK_MUTEX(raidPtr->recon_done_proc_mutex);
136 for (p = raidPtr->recon_done_procs; p; p = p->next) {
137 p->proc(raidPtr, p->arg);
138 }
139 RF_UNLOCK_MUTEX(raidPtr->recon_done_proc_mutex);
140 }
141
142 int
143 rf_RegisterReconDoneProc(
144 RF_Raid_t * raidPtr,
145 void (*proc) (RF_Raid_t *, void *),
146 void *arg,
147 RF_ReconDoneProc_t ** handlep)
148 {
149 RF_ReconDoneProc_t *p;
150
151 RF_FREELIST_GET(rf_rdp_freelist, p, next, (RF_ReconDoneProc_t *));
152 if (p == NULL)
153 return (ENOMEM);
154 p->proc = proc;
155 p->arg = arg;
156 RF_LOCK_MUTEX(raidPtr->recon_done_proc_mutex);
157 p->next = raidPtr->recon_done_procs;
158 raidPtr->recon_done_procs = p;
159 RF_UNLOCK_MUTEX(raidPtr->recon_done_proc_mutex);
160 if (handlep)
161 *handlep = p;
162 return (0);
163 }
164 /**************************************************************************
165 *
166 * sets up the parameters that will be used by the reconstruction process
167 * currently there are none, except for those that the layout-specific
168 * configuration (e.g. rf_ConfigureDeclustered) routine sets up.
169 *
170 * in the kernel, we fire off the recon thread.
171 *
172 **************************************************************************/
173 static void
174 rf_ShutdownReconstruction(ignored)
175 void *ignored;
176 {
177 RF_FREELIST_DESTROY(rf_recond_freelist, next, (RF_RaidReconDesc_t *));
178 RF_FREELIST_DESTROY(rf_rdp_freelist, next, (RF_ReconDoneProc_t *));
179 }
180
181 int
182 rf_ConfigureReconstruction(listp)
183 RF_ShutdownList_t **listp;
184 {
185 int rc;
186
187 RF_FREELIST_CREATE(rf_recond_freelist, RF_MAX_FREE_RECOND,
188 RF_RECOND_INC, sizeof(RF_RaidReconDesc_t));
189 if (rf_recond_freelist == NULL)
190 return (ENOMEM);
191 RF_FREELIST_CREATE(rf_rdp_freelist, RF_MAX_FREE_RDP,
192 RF_RDP_INC, sizeof(RF_ReconDoneProc_t));
193 if (rf_rdp_freelist == NULL) {
194 RF_FREELIST_DESTROY(rf_recond_freelist, next, (RF_RaidReconDesc_t *));
195 return (ENOMEM);
196 }
197 rc = rf_ShutdownCreate(listp, rf_ShutdownReconstruction, NULL);
198 if (rc) {
199 RF_ERRORMSG3("Unable to add to shutdown list file %s line %d rc=%d\n",
200 __FILE__, __LINE__, rc);
201 rf_ShutdownReconstruction(NULL);
202 return (rc);
203 }
204 return (0);
205 }
206
207 static RF_RaidReconDesc_t *
208 AllocRaidReconDesc(raidPtr, row, col, spareDiskPtr, numDisksDone, srow, scol)
209 RF_Raid_t *raidPtr;
210 RF_RowCol_t row;
211 RF_RowCol_t col;
212 RF_RaidDisk_t *spareDiskPtr;
213 int numDisksDone;
214 RF_RowCol_t srow;
215 RF_RowCol_t scol;
216 {
217
218 RF_RaidReconDesc_t *reconDesc;
219
220 RF_FREELIST_GET(rf_recond_freelist, reconDesc, next, (RF_RaidReconDesc_t *));
221
222 reconDesc->raidPtr = raidPtr;
223 reconDesc->row = row;
224 reconDesc->col = col;
225 reconDesc->spareDiskPtr = spareDiskPtr;
226 reconDesc->numDisksDone = numDisksDone;
227 reconDesc->srow = srow;
228 reconDesc->scol = scol;
229 reconDesc->state = 0;
230 reconDesc->next = NULL;
231
232 return (reconDesc);
233 }
234
235 static void
236 FreeReconDesc(reconDesc)
237 RF_RaidReconDesc_t *reconDesc;
238 {
239 #if RF_RECON_STATS > 0
240 printf("RAIDframe: %lu recon event waits, %lu recon delays\n",
241 (long) reconDesc->numReconEventWaits, (long) reconDesc->numReconExecDelays);
242 #endif /* RF_RECON_STATS > 0 */
243 printf("RAIDframe: %lu max exec ticks\n",
244 (long) reconDesc->maxReconExecTicks);
245 #if (RF_RECON_STATS > 0) || defined(KERNEL)
246 printf("\n");
247 #endif /* (RF_RECON_STATS > 0) || KERNEL */
248 RF_FREELIST_FREE(rf_recond_freelist, reconDesc, next);
249 }
250
251
252 /*****************************************************************************
253 *
254 * primary routine to reconstruct a failed disk. This should be called from
255 * within its own thread. It won't return until reconstruction completes,
256 * fails, or is aborted.
257 *****************************************************************************/
258 int
259 rf_ReconstructFailedDisk(raidPtr, row, col)
260 RF_Raid_t *raidPtr;
261 RF_RowCol_t row;
262 RF_RowCol_t col;
263 {
264 RF_LayoutSW_t *lp;
265 int rc;
266
267 lp = raidPtr->Layout.map;
268 if (lp->SubmitReconBuffer) {
269 /*
270 * The current infrastructure only supports reconstructing one
271 * disk at a time for each array.
272 */
273 RF_LOCK_MUTEX(raidPtr->mutex);
274 while (raidPtr->reconInProgress) {
275 RF_WAIT_COND(raidPtr->waitForReconCond, raidPtr->mutex);
276 }
277 raidPtr->reconInProgress++;
278 RF_UNLOCK_MUTEX(raidPtr->mutex);
279 rc = rf_ReconstructFailedDiskBasic(raidPtr, row, col);
280 RF_LOCK_MUTEX(raidPtr->mutex);
281 raidPtr->reconInProgress--;
282 RF_UNLOCK_MUTEX(raidPtr->mutex);
283 } else {
284 RF_ERRORMSG1("RECON: no way to reconstruct failed disk for arch %c\n",
285 lp->parityConfig);
286 rc = EIO;
287 }
288 RF_SIGNAL_COND(raidPtr->waitForReconCond);
289 wakeup(&raidPtr->waitForReconCond); /* XXX Methinks this will be
290 * needed at some point... GO */
291 return (rc);
292 }
293
294 int
295 rf_ReconstructFailedDiskBasic(raidPtr, row, col)
296 RF_Raid_t *raidPtr;
297 RF_RowCol_t row;
298 RF_RowCol_t col;
299 {
300 RF_ComponentLabel_t c_label;
301 RF_RaidDisk_t *spareDiskPtr = NULL;
302 RF_RaidReconDesc_t *reconDesc;
303 RF_RowCol_t srow, scol;
304 int numDisksDone = 0, rc;
305
306 /* first look for a spare drive onto which to reconstruct the data */
307 /* spare disk descriptors are stored in row 0. This may have to
308 * change eventually */
309
310 RF_LOCK_MUTEX(raidPtr->mutex);
311 RF_ASSERT(raidPtr->Disks[row][col].status == rf_ds_failed);
312
313 if (raidPtr->Layout.map->flags & RF_DISTRIBUTE_SPARE) {
314 if (raidPtr->status[row] != rf_rs_degraded) {
315 RF_ERRORMSG2("Unable to reconstruct disk at row %d col %d because status not degraded\n", row, col);
316 RF_UNLOCK_MUTEX(raidPtr->mutex);
317 return (EINVAL);
318 }
319 srow = row;
320 scol = (-1);
321 } else {
322 srow = 0;
323 for (scol = raidPtr->numCol; scol < raidPtr->numCol + raidPtr->numSpare; scol++) {
324 if (raidPtr->Disks[srow][scol].status == rf_ds_spare) {
325 spareDiskPtr = &raidPtr->Disks[srow][scol];
326 spareDiskPtr->status = rf_ds_used_spare;
327 break;
328 }
329 }
330 if (!spareDiskPtr) {
331 RF_ERRORMSG2("Unable to reconstruct disk at row %d col %d because no spares are available\n", row, col);
332 RF_UNLOCK_MUTEX(raidPtr->mutex);
333 return (ENOSPC);
334 }
335 printf("RECON: initiating reconstruction on row %d col %d -> spare at row %d col %d\n", row, col, srow, scol);
336 }
337 RF_UNLOCK_MUTEX(raidPtr->mutex);
338
339 reconDesc = AllocRaidReconDesc((void *) raidPtr, row, col, spareDiskPtr, numDisksDone, srow, scol);
340 raidPtr->reconDesc = (void *) reconDesc;
341 #if RF_RECON_STATS > 0
342 reconDesc->hsStallCount = 0;
343 reconDesc->numReconExecDelays = 0;
344 reconDesc->numReconEventWaits = 0;
345 #endif /* RF_RECON_STATS > 0 */
346 reconDesc->reconExecTimerRunning = 0;
347 reconDesc->reconExecTicks = 0;
348 reconDesc->maxReconExecTicks = 0;
349 rc = rf_ContinueReconstructFailedDisk(reconDesc);
350
351 if (!rc) {
352 /* fix up the component label */
353 /* Don't actually need the read here.. */
354 raidread_component_label(
355 raidPtr->raid_cinfo[srow][scol].ci_dev,
356 raidPtr->raid_cinfo[srow][scol].ci_vp,
357 &c_label);
358
359 raid_init_component_label( raidPtr, &c_label);
360 c_label.row = row;
361 c_label.column = col;
362 c_label.clean = RF_RAID_DIRTY;
363 c_label.status = rf_ds_optimal;
364 c_label.partitionSize = raidPtr->Disks[srow][scol].partitionSize;
365
366 /* XXXX MORE NEEDED HERE */
367
368 raidwrite_component_label(
369 raidPtr->raid_cinfo[srow][scol].ci_dev,
370 raidPtr->raid_cinfo[srow][scol].ci_vp,
371 &c_label);
372
373 }
374 return (rc);
375 }
376
377 /*
378
379 Allow reconstructing a disk in-place -- i.e. component /dev/sd2e goes AWOL,
380 and you don't get a spare until the next Monday. With this function
381 (and hot-swappable drives) you can now put your new disk containing
382 /dev/sd2e on the bus, scsictl it alive, and then use raidctl(8) to
383 rebuild the data "on the spot".
384
385 */
386
387 int
388 rf_ReconstructInPlace(raidPtr, row, col)
389 RF_Raid_t *raidPtr;
390 RF_RowCol_t row;
391 RF_RowCol_t col;
392 {
393 RF_RaidDisk_t *spareDiskPtr = NULL;
394 RF_RaidReconDesc_t *reconDesc;
395 RF_LayoutSW_t *lp;
396 RF_RaidDisk_t *badDisk;
397 RF_ComponentLabel_t c_label;
398 int numDisksDone = 0, rc;
399 struct partinfo dpart;
400 struct vnode *vp;
401 struct vattr va;
402 struct proc *proc;
403 int retcode;
404 int ac;
405
406 lp = raidPtr->Layout.map;
407 if (lp->SubmitReconBuffer) {
408 /*
409 * The current infrastructure only supports reconstructing one
410 * disk at a time for each array.
411 */
412 RF_LOCK_MUTEX(raidPtr->mutex);
413 if ((raidPtr->Disks[row][col].status == rf_ds_optimal) &&
414 (raidPtr->numFailures > 0)) {
415 /* XXX 0 above shouldn't be constant!!! */
416 /* some component other than this has failed.
417 Let's not make things worse than they already
418 are... */
419 printf("RAIDFRAME: Unable to reconstruct to disk at:\n");
420 printf(" Row: %d Col: %d Too many failures.\n",
421 row, col);
422 RF_UNLOCK_MUTEX(raidPtr->mutex);
423 return (EINVAL);
424 }
425 if (raidPtr->Disks[row][col].status == rf_ds_reconstructing) {
426 printf("RAIDFRAME: Unable to reconstruct to disk at:\n");
427 printf(" Row: %d Col: %d Reconstruction already occuring!\n", row, col);
428
429 RF_UNLOCK_MUTEX(raidPtr->mutex);
430 return (EINVAL);
431 }
432
433
434 if (raidPtr->Disks[row][col].status != rf_ds_failed) {
435 /* "It's gone..." */
436 raidPtr->numFailures++;
437 raidPtr->Disks[row][col].status = rf_ds_failed;
438 raidPtr->status[row] = rf_rs_degraded;
439 rf_update_component_labels(raidPtr,
440 RF_NORMAL_COMPONENT_UPDATE);
441 }
442
443 while (raidPtr->reconInProgress) {
444 RF_WAIT_COND(raidPtr->waitForReconCond, raidPtr->mutex);
445 }
446
447 raidPtr->reconInProgress++;
448
449
450 /* first look for a spare drive onto which to reconstruct
451 the data. spare disk descriptors are stored in row 0.
452 This may have to change eventually */
453
454 /* Actually, we don't care if it's failed or not...
455 On a RAID set with correct parity, this function
456 should be callable on any component without ill affects. */
457 /* RF_ASSERT(raidPtr->Disks[row][col].status == rf_ds_failed);
458 */
459
460 if (raidPtr->Layout.map->flags & RF_DISTRIBUTE_SPARE) {
461 RF_ERRORMSG2("Unable to reconstruct to disk at row %d col %d: operation not supported for RF_DISTRIBUTE_SPARE\n", row, col);
462
463 raidPtr->reconInProgress--;
464 RF_UNLOCK_MUTEX(raidPtr->mutex);
465 return (EINVAL);
466 }
467
468 /* XXX need goop here to see if the disk is alive,
469 and, if not, make it so... */
470
471
472
473 badDisk = &raidPtr->Disks[row][col];
474
475 proc = raidPtr->engine_thread;
476
477 /* This device may have been opened successfully the
478 first time. Close it before trying to open it again.. */
479
480 if (raidPtr->raid_cinfo[row][col].ci_vp != NULL) {
481 printf("Closed the open device: %s\n",
482 raidPtr->Disks[row][col].devname);
483 vp = raidPtr->raid_cinfo[row][col].ci_vp;
484 ac = raidPtr->Disks[row][col].auto_configured;
485 rf_close_component(raidPtr, vp, ac);
486 raidPtr->raid_cinfo[row][col].ci_vp = NULL;
487 }
488 /* note that this disk was *not* auto_configured (any longer)*/
489 raidPtr->Disks[row][col].auto_configured = 0;
490
491 printf("About to (re-)open the device for rebuilding: %s\n",
492 raidPtr->Disks[row][col].devname);
493
494 retcode = raidlookup(raidPtr->Disks[row][col].devname,
495 proc, &vp);
496
497 if (retcode) {
498 printf("raid%d: rebuilding: raidlookup on device: %s failed: %d!\n",raidPtr->raidid,
499 raidPtr->Disks[row][col].devname, retcode);
500
501 /* XXX the component isn't responding properly...
502 must be still dead :-( */
503 raidPtr->reconInProgress--;
504 RF_UNLOCK_MUTEX(raidPtr->mutex);
505 return(retcode);
506
507 } else {
508
509 /* Ok, so we can at least do a lookup...
510 How about actually getting a vp for it? */
511
512 if ((retcode = VOP_GETATTR(vp, &va, proc->p_ucred,
513 proc)) != 0) {
514 raidPtr->reconInProgress--;
515 RF_UNLOCK_MUTEX(raidPtr->mutex);
516 return(retcode);
517 }
518 retcode = VOP_IOCTL(vp, DIOCGPART, (caddr_t) & dpart,
519 FREAD, proc->p_ucred, proc);
520 if (retcode) {
521 raidPtr->reconInProgress--;
522 RF_UNLOCK_MUTEX(raidPtr->mutex);
523 return(retcode);
524 }
525 raidPtr->Disks[row][col].blockSize =
526 dpart.disklab->d_secsize;
527
528 raidPtr->Disks[row][col].numBlocks =
529 dpart.part->p_size - rf_protectedSectors;
530
531 raidPtr->raid_cinfo[row][col].ci_vp = vp;
532 raidPtr->raid_cinfo[row][col].ci_dev = va.va_rdev;
533
534 raidPtr->Disks[row][col].dev = va.va_rdev;
535
536 /* we allow the user to specify that only a
537 fraction of the disks should be used this is
538 just for debug: it speeds up
539 * the parity scan */
540 raidPtr->Disks[row][col].numBlocks =
541 raidPtr->Disks[row][col].numBlocks *
542 rf_sizePercentage / 100;
543 }
544
545
546
547 spareDiskPtr = &raidPtr->Disks[row][col];
548 spareDiskPtr->status = rf_ds_used_spare;
549
550 printf("RECON: initiating in-place reconstruction on\n");
551 printf(" row %d col %d -> spare at row %d col %d\n",
552 row, col, row, col);
553
554 RF_UNLOCK_MUTEX(raidPtr->mutex);
555
556 reconDesc = AllocRaidReconDesc((void *) raidPtr, row, col,
557 spareDiskPtr, numDisksDone,
558 row, col);
559 raidPtr->reconDesc = (void *) reconDesc;
560 #if RF_RECON_STATS > 0
561 reconDesc->hsStallCount = 0;
562 reconDesc->numReconExecDelays = 0;
563 reconDesc->numReconEventWaits = 0;
564 #endif /* RF_RECON_STATS > 0 */
565 reconDesc->reconExecTimerRunning = 0;
566 reconDesc->reconExecTicks = 0;
567 reconDesc->maxReconExecTicks = 0;
568 rc = rf_ContinueReconstructFailedDisk(reconDesc);
569
570 RF_LOCK_MUTEX(raidPtr->mutex);
571 raidPtr->reconInProgress--;
572 RF_UNLOCK_MUTEX(raidPtr->mutex);
573
574 } else {
575 RF_ERRORMSG1("RECON: no way to reconstruct failed disk for arch %c\n",
576 lp->parityConfig);
577 rc = EIO;
578 }
579 RF_LOCK_MUTEX(raidPtr->mutex);
580
581 if (!rc) {
582 /* Need to set these here, as at this point it'll be claiming
583 that the disk is in rf_ds_spared! But we know better :-) */
584
585 raidPtr->Disks[row][col].status = rf_ds_optimal;
586 raidPtr->status[row] = rf_rs_optimal;
587
588 /* fix up the component label */
589 /* Don't actually need the read here.. */
590 raidread_component_label(raidPtr->raid_cinfo[row][col].ci_dev,
591 raidPtr->raid_cinfo[row][col].ci_vp,
592 &c_label);
593
594 raid_init_component_label(raidPtr, &c_label);
595
596 c_label.row = row;
597 c_label.column = col;
598
599 raidwrite_component_label(raidPtr->raid_cinfo[row][col].ci_dev,
600 raidPtr->raid_cinfo[row][col].ci_vp,
601 &c_label);
602
603 }
604 RF_UNLOCK_MUTEX(raidPtr->mutex);
605 RF_SIGNAL_COND(raidPtr->waitForReconCond);
606 wakeup(&raidPtr->waitForReconCond);
607 return (rc);
608 }
609
610
611 int
612 rf_ContinueReconstructFailedDisk(reconDesc)
613 RF_RaidReconDesc_t *reconDesc;
614 {
615 RF_Raid_t *raidPtr = reconDesc->raidPtr;
616 RF_RowCol_t row = reconDesc->row;
617 RF_RowCol_t col = reconDesc->col;
618 RF_RowCol_t srow = reconDesc->srow;
619 RF_RowCol_t scol = reconDesc->scol;
620 RF_ReconMap_t *mapPtr;
621
622 RF_ReconEvent_t *event;
623 struct timeval etime, elpsd;
624 unsigned long xor_s, xor_resid_us;
625 int retcode, i, ds;
626
627 switch (reconDesc->state) {
628
629
630 case 0:
631
632 raidPtr->accumXorTimeUs = 0;
633
634 /* create one trace record per physical disk */
635 RF_Malloc(raidPtr->recon_tracerecs, raidPtr->numCol * sizeof(RF_AccTraceEntry_t), (RF_AccTraceEntry_t *));
636
637 /* quiesce the array prior to starting recon. this is needed
638 * to assure no nasty interactions with pending user writes.
639 * We need to do this before we change the disk or row status. */
640 reconDesc->state = 1;
641
642 Dprintf("RECON: begin request suspend\n");
643 retcode = rf_SuspendNewRequestsAndWait(raidPtr);
644 Dprintf("RECON: end request suspend\n");
645 rf_StartUserStats(raidPtr); /* zero out the stats kept on
646 * user accs */
647
648 /* fall through to state 1 */
649
650 case 1:
651
652 RF_LOCK_MUTEX(raidPtr->mutex);
653
654 /* create the reconstruction control pointer and install it in
655 * the right slot */
656 raidPtr->reconControl[row] = rf_MakeReconControl(reconDesc, row, col, srow, scol);
657 mapPtr = raidPtr->reconControl[row]->reconMap;
658 raidPtr->status[row] = rf_rs_reconstructing;
659 raidPtr->Disks[row][col].status = rf_ds_reconstructing;
660 raidPtr->Disks[row][col].spareRow = srow;
661 raidPtr->Disks[row][col].spareCol = scol;
662
663 RF_UNLOCK_MUTEX(raidPtr->mutex);
664
665 RF_GETTIME(raidPtr->reconControl[row]->starttime);
666
667 /* now start up the actual reconstruction: issue a read for
668 * each surviving disk */
669
670 reconDesc->numDisksDone = 0;
671 for (i = 0; i < raidPtr->numCol; i++) {
672 if (i != col) {
673 /* find and issue the next I/O on the
674 * indicated disk */
675 if (IssueNextReadRequest(raidPtr, row, i)) {
676 Dprintf2("RECON: done issuing for r%d c%d\n", row, i);
677 reconDesc->numDisksDone++;
678 }
679 }
680 }
681
682 case 2:
683 Dprintf("RECON: resume requests\n");
684 rf_ResumeNewRequests(raidPtr);
685
686
687 reconDesc->state = 3;
688
689 case 3:
690
691 /* process reconstruction events until all disks report that
692 * they've completed all work */
693 mapPtr = raidPtr->reconControl[row]->reconMap;
694
695
696
697 while (reconDesc->numDisksDone < raidPtr->numCol - 1) {
698
699 event = rf_GetNextReconEvent(reconDesc, row, (void (*) (void *)) rf_ContinueReconstructFailedDisk, reconDesc);
700 RF_ASSERT(event);
701
702 if (ProcessReconEvent(raidPtr, row, event))
703 reconDesc->numDisksDone++;
704 raidPtr->reconControl[row]->numRUsTotal =
705 mapPtr->totalRUs;
706 raidPtr->reconControl[row]->numRUsComplete =
707 mapPtr->totalRUs -
708 rf_UnitsLeftToReconstruct(mapPtr);
709
710 raidPtr->reconControl[row]->percentComplete =
711 (raidPtr->reconControl[row]->numRUsComplete * 100 / raidPtr->reconControl[row]->numRUsTotal);
712 if (rf_prReconSched) {
713 rf_PrintReconSchedule(raidPtr->reconControl[row]->reconMap, &(raidPtr->reconControl[row]->starttime));
714 }
715 }
716
717
718
719 reconDesc->state = 4;
720
721
722 case 4:
723 mapPtr = raidPtr->reconControl[row]->reconMap;
724 if (rf_reconDebug) {
725 printf("RECON: all reads completed\n");
726 }
727 /* at this point all the reads have completed. We now wait
728 * for any pending writes to complete, and then we're done */
729
730 while (rf_UnitsLeftToReconstruct(raidPtr->reconControl[row]->reconMap) > 0) {
731
732 event = rf_GetNextReconEvent(reconDesc, row, (void (*) (void *)) rf_ContinueReconstructFailedDisk, reconDesc);
733 RF_ASSERT(event);
734
735 (void) ProcessReconEvent(raidPtr, row, event); /* ignore return code */
736 raidPtr->reconControl[row]->percentComplete = 100 - (rf_UnitsLeftToReconstruct(mapPtr) * 100 / mapPtr->totalRUs);
737 if (rf_prReconSched) {
738 rf_PrintReconSchedule(raidPtr->reconControl[row]->reconMap, &(raidPtr->reconControl[row]->starttime));
739 }
740 }
741 reconDesc->state = 5;
742
743 case 5:
744 /* Success: mark the dead disk as reconstructed. We quiesce
745 * the array here to assure no nasty interactions with pending
746 * user accesses when we free up the psstatus structure as
747 * part of FreeReconControl() */
748
749 reconDesc->state = 6;
750
751 retcode = rf_SuspendNewRequestsAndWait(raidPtr);
752 rf_StopUserStats(raidPtr);
753 rf_PrintUserStats(raidPtr); /* print out the stats on user
754 * accs accumulated during
755 * recon */
756
757 /* fall through to state 6 */
758 case 6:
759
760
761
762 RF_LOCK_MUTEX(raidPtr->mutex);
763 raidPtr->numFailures--;
764 ds = (raidPtr->Layout.map->flags & RF_DISTRIBUTE_SPARE);
765 raidPtr->Disks[row][col].status = (ds) ? rf_ds_dist_spared : rf_ds_spared;
766 raidPtr->status[row] = (ds) ? rf_rs_reconfigured : rf_rs_optimal;
767 RF_UNLOCK_MUTEX(raidPtr->mutex);
768 RF_GETTIME(etime);
769 RF_TIMEVAL_DIFF(&(raidPtr->reconControl[row]->starttime), &etime, &elpsd);
770
771 /* XXX -- why is state 7 different from state 6 if there is no
772 * return() here? -- XXX Note that I set elpsd above & use it
773 * below, so if you put a return here you'll have to fix this.
774 * (also, FreeReconControl is called below) */
775
776 case 7:
777
778 rf_ResumeNewRequests(raidPtr);
779
780 printf("Reconstruction of disk at row %d col %d completed\n",
781 row, col);
782 xor_s = raidPtr->accumXorTimeUs / 1000000;
783 xor_resid_us = raidPtr->accumXorTimeUs % 1000000;
784 printf("Recon time was %d.%06d seconds, accumulated XOR time was %ld us (%ld.%06ld)\n",
785 (int) elpsd.tv_sec, (int) elpsd.tv_usec, raidPtr->accumXorTimeUs, xor_s, xor_resid_us);
786 printf(" (start time %d sec %d usec, end time %d sec %d usec)\n",
787 (int) raidPtr->reconControl[row]->starttime.tv_sec,
788 (int) raidPtr->reconControl[row]->starttime.tv_usec,
789 (int) etime.tv_sec, (int) etime.tv_usec);
790
791 #if RF_RECON_STATS > 0
792 printf("Total head-sep stall count was %d\n",
793 (int) reconDesc->hsStallCount);
794 #endif /* RF_RECON_STATS > 0 */
795 rf_FreeReconControl(raidPtr, row);
796 RF_Free(raidPtr->recon_tracerecs, raidPtr->numCol * sizeof(RF_AccTraceEntry_t));
797 FreeReconDesc(reconDesc);
798
799 }
800
801 SignalReconDone(raidPtr);
802 return (0);
803 }
804 /*****************************************************************************
805 * do the right thing upon each reconstruction event.
806 * returns nonzero if and only if there is nothing left unread on the
807 * indicated disk
808 *****************************************************************************/
809 static int
810 ProcessReconEvent(raidPtr, frow, event)
811 RF_Raid_t *raidPtr;
812 RF_RowCol_t frow;
813 RF_ReconEvent_t *event;
814 {
815 int retcode = 0, submitblocked;
816 RF_ReconBuffer_t *rbuf;
817 RF_SectorCount_t sectorsPerRU;
818
819 Dprintf1("RECON: ProcessReconEvent type %d\n", event->type);
820 switch (event->type) {
821
822 /* a read I/O has completed */
823 case RF_REVENT_READDONE:
824 rbuf = raidPtr->reconControl[frow]->perDiskInfo[event->col].rbuf;
825 Dprintf3("RECON: READDONE EVENT: row %d col %d psid %ld\n",
826 frow, event->col, rbuf->parityStripeID);
827 Dprintf7("RECON: done read psid %ld buf %lx %02x %02x %02x %02x %02x\n",
828 rbuf->parityStripeID, rbuf->buffer, rbuf->buffer[0] & 0xff, rbuf->buffer[1] & 0xff,
829 rbuf->buffer[2] & 0xff, rbuf->buffer[3] & 0xff, rbuf->buffer[4] & 0xff);
830 rf_FreeDiskQueueData((RF_DiskQueueData_t *) rbuf->arg);
831 submitblocked = rf_SubmitReconBuffer(rbuf, 0, 0);
832 Dprintf1("RECON: submitblocked=%d\n", submitblocked);
833 if (!submitblocked)
834 retcode = IssueNextReadRequest(raidPtr, frow, event->col);
835 break;
836
837 /* a write I/O has completed */
838 case RF_REVENT_WRITEDONE:
839 if (rf_floatingRbufDebug) {
840 rf_CheckFloatingRbufCount(raidPtr, 1);
841 }
842 sectorsPerRU = raidPtr->Layout.sectorsPerStripeUnit * raidPtr->Layout.SUsPerRU;
843 rbuf = (RF_ReconBuffer_t *) event->arg;
844 rf_FreeDiskQueueData((RF_DiskQueueData_t *) rbuf->arg);
845 Dprintf3("RECON: WRITEDONE EVENT: psid %d ru %d (%d %% complete)\n",
846 rbuf->parityStripeID, rbuf->which_ru, raidPtr->reconControl[frow]->percentComplete);
847 rf_ReconMapUpdate(raidPtr, raidPtr->reconControl[frow]->reconMap,
848 rbuf->failedDiskSectorOffset, rbuf->failedDiskSectorOffset + sectorsPerRU - 1);
849 rf_RemoveFromActiveReconTable(raidPtr, frow, rbuf->parityStripeID, rbuf->which_ru);
850
851 if (rbuf->type == RF_RBUF_TYPE_FLOATING) {
852 RF_LOCK_MUTEX(raidPtr->reconControl[frow]->rb_mutex);
853 raidPtr->numFullReconBuffers--;
854 rf_ReleaseFloatingReconBuffer(raidPtr, frow, rbuf);
855 RF_UNLOCK_MUTEX(raidPtr->reconControl[frow]->rb_mutex);
856 } else
857 if (rbuf->type == RF_RBUF_TYPE_FORCED)
858 rf_FreeReconBuffer(rbuf);
859 else
860 RF_ASSERT(0);
861 break;
862
863 case RF_REVENT_BUFCLEAR: /* A buffer-stall condition has been
864 * cleared */
865 Dprintf2("RECON: BUFCLEAR EVENT: row %d col %d\n", frow, event->col);
866 submitblocked = rf_SubmitReconBuffer(raidPtr->reconControl[frow]->perDiskInfo[event->col].rbuf, 0, (int) (long) event->arg);
867 RF_ASSERT(!submitblocked); /* we wouldn't have gotten the
868 * BUFCLEAR event if we
869 * couldn't submit */
870 retcode = IssueNextReadRequest(raidPtr, frow, event->col);
871 break;
872
873 case RF_REVENT_BLOCKCLEAR: /* A user-write reconstruction
874 * blockage has been cleared */
875 DDprintf2("RECON: BLOCKCLEAR EVENT: row %d col %d\n", frow, event->col);
876 retcode = TryToRead(raidPtr, frow, event->col);
877 break;
878
879 case RF_REVENT_HEADSEPCLEAR: /* A max-head-separation
880 * reconstruction blockage has been
881 * cleared */
882 Dprintf2("RECON: HEADSEPCLEAR EVENT: row %d col %d\n", frow, event->col);
883 retcode = TryToRead(raidPtr, frow, event->col);
884 break;
885
886 /* a buffer has become ready to write */
887 case RF_REVENT_BUFREADY:
888 Dprintf2("RECON: BUFREADY EVENT: row %d col %d\n", frow, event->col);
889 retcode = IssueNextWriteRequest(raidPtr, frow);
890 if (rf_floatingRbufDebug) {
891 rf_CheckFloatingRbufCount(raidPtr, 1);
892 }
893 break;
894
895 /* we need to skip the current RU entirely because it got
896 * recon'd while we were waiting for something else to happen */
897 case RF_REVENT_SKIP:
898 DDprintf2("RECON: SKIP EVENT: row %d col %d\n", frow, event->col);
899 retcode = IssueNextReadRequest(raidPtr, frow, event->col);
900 break;
901
902 /* a forced-reconstruction read access has completed. Just
903 * submit the buffer */
904 case RF_REVENT_FORCEDREADDONE:
905 rbuf = (RF_ReconBuffer_t *) event->arg;
906 rf_FreeDiskQueueData((RF_DiskQueueData_t *) rbuf->arg);
907 DDprintf2("RECON: FORCEDREADDONE EVENT: row %d col %d\n", frow, event->col);
908 submitblocked = rf_SubmitReconBuffer(rbuf, 1, 0);
909 RF_ASSERT(!submitblocked);
910 break;
911
912 default:
913 RF_PANIC();
914 }
915 rf_FreeReconEventDesc(event);
916 return (retcode);
917 }
918 /*****************************************************************************
919 *
920 * find the next thing that's needed on the indicated disk, and issue
921 * a read request for it. We assume that the reconstruction buffer
922 * associated with this process is free to receive the data. If
923 * reconstruction is blocked on the indicated RU, we issue a
924 * blockage-release request instead of a physical disk read request.
925 * If the current disk gets too far ahead of the others, we issue a
926 * head-separation wait request and return.
927 *
928 * ctrl->{ru_count, curPSID, diskOffset} and
929 * rbuf->failedDiskSectorOffset are maintained to point to the unit
930 * we're currently accessing. Note that this deviates from the
931 * standard C idiom of having counters point to the next thing to be
932 * accessed. This allows us to easily retry when we're blocked by
933 * head separation or reconstruction-blockage events.
934 *
935 * returns nonzero if and only if there is nothing left unread on the
936 * indicated disk
937 *
938 *****************************************************************************/
939 static int
940 IssueNextReadRequest(raidPtr, row, col)
941 RF_Raid_t *raidPtr;
942 RF_RowCol_t row;
943 RF_RowCol_t col;
944 {
945 RF_PerDiskReconCtrl_t *ctrl = &raidPtr->reconControl[row]->perDiskInfo[col];
946 RF_RaidLayout_t *layoutPtr = &raidPtr->Layout;
947 RF_ReconBuffer_t *rbuf = ctrl->rbuf;
948 RF_ReconUnitCount_t RUsPerPU = layoutPtr->SUsPerPU / layoutPtr->SUsPerRU;
949 RF_SectorCount_t sectorsPerRU = layoutPtr->sectorsPerStripeUnit * layoutPtr->SUsPerRU;
950 int do_new_check = 0, retcode = 0, status;
951
952 /* if we are currently the slowest disk, mark that we have to do a new
953 * check */
954 if (ctrl->headSepCounter <= raidPtr->reconControl[row]->minHeadSepCounter)
955 do_new_check = 1;
956
957 while (1) {
958
959 ctrl->ru_count++;
960 if (ctrl->ru_count < RUsPerPU) {
961 ctrl->diskOffset += sectorsPerRU;
962 rbuf->failedDiskSectorOffset += sectorsPerRU;
963 } else {
964 ctrl->curPSID++;
965 ctrl->ru_count = 0;
966 /* code left over from when head-sep was based on
967 * parity stripe id */
968 if (ctrl->curPSID >= raidPtr->reconControl[row]->lastPSID) {
969 CheckForNewMinHeadSep(raidPtr, row, ++(ctrl->headSepCounter));
970 return (1); /* finito! */
971 }
972 /* find the disk offsets of the start of the parity
973 * stripe on both the current disk and the failed
974 * disk. skip this entire parity stripe if either disk
975 * does not appear in the indicated PS */
976 status = ComputePSDiskOffsets(raidPtr, ctrl->curPSID, row, col, &ctrl->diskOffset, &rbuf->failedDiskSectorOffset,
977 &rbuf->spRow, &rbuf->spCol, &rbuf->spOffset);
978 if (status) {
979 ctrl->ru_count = RUsPerPU - 1;
980 continue;
981 }
982 }
983 rbuf->which_ru = ctrl->ru_count;
984
985 /* skip this RU if it's already been reconstructed */
986 if (rf_CheckRUReconstructed(raidPtr->reconControl[row]->reconMap, rbuf->failedDiskSectorOffset)) {
987 Dprintf2("Skipping psid %ld ru %d: already reconstructed\n", ctrl->curPSID, ctrl->ru_count);
988 continue;
989 }
990 break;
991 }
992 ctrl->headSepCounter++;
993 if (do_new_check)
994 CheckForNewMinHeadSep(raidPtr, row, ctrl->headSepCounter); /* update min if needed */
995
996
997 /* at this point, we have definitely decided what to do, and we have
998 * only to see if we can actually do it now */
999 rbuf->parityStripeID = ctrl->curPSID;
1000 rbuf->which_ru = ctrl->ru_count;
1001 bzero((char *) &raidPtr->recon_tracerecs[col], sizeof(raidPtr->recon_tracerecs[col]));
1002 raidPtr->recon_tracerecs[col].reconacc = 1;
1003 RF_ETIMER_START(raidPtr->recon_tracerecs[col].recon_timer);
1004 retcode = TryToRead(raidPtr, row, col);
1005 return (retcode);
1006 }
1007
1008 /*
1009 * tries to issue the next read on the indicated disk. We may be
1010 * blocked by (a) the heads being too far apart, or (b) recon on the
1011 * indicated RU being blocked due to a write by a user thread. In
1012 * this case, we issue a head-sep or blockage wait request, which will
1013 * cause this same routine to be invoked again later when the blockage
1014 * has cleared.
1015 */
1016
1017 static int
1018 TryToRead(raidPtr, row, col)
1019 RF_Raid_t *raidPtr;
1020 RF_RowCol_t row;
1021 RF_RowCol_t col;
1022 {
1023 RF_PerDiskReconCtrl_t *ctrl = &raidPtr->reconControl[row]->perDiskInfo[col];
1024 RF_SectorCount_t sectorsPerRU = raidPtr->Layout.sectorsPerStripeUnit * raidPtr->Layout.SUsPerRU;
1025 RF_StripeNum_t psid = ctrl->curPSID;
1026 RF_ReconUnitNum_t which_ru = ctrl->ru_count;
1027 RF_DiskQueueData_t *req;
1028 int status, created = 0;
1029 RF_ReconParityStripeStatus_t *pssPtr;
1030
1031 /* if the current disk is too far ahead of the others, issue a
1032 * head-separation wait and return */
1033 if (CheckHeadSeparation(raidPtr, ctrl, row, col, ctrl->headSepCounter, which_ru))
1034 return (0);
1035 RF_LOCK_PSS_MUTEX(raidPtr, row, psid);
1036 pssPtr = rf_LookupRUStatus(raidPtr, raidPtr->reconControl[row]->pssTable, psid, which_ru, RF_PSS_CREATE, &created);
1037
1038 /* if recon is blocked on the indicated parity stripe, issue a
1039 * block-wait request and return. this also must mark the indicated RU
1040 * in the stripe as under reconstruction if not blocked. */
1041 status = CheckForcedOrBlockedReconstruction(raidPtr, pssPtr, ctrl, row, col, psid, which_ru);
1042 if (status == RF_PSS_RECON_BLOCKED) {
1043 Dprintf2("RECON: Stalling psid %ld ru %d: recon blocked\n", psid, which_ru);
1044 goto out;
1045 } else
1046 if (status == RF_PSS_FORCED_ON_WRITE) {
1047 rf_CauseReconEvent(raidPtr, row, col, NULL, RF_REVENT_SKIP);
1048 goto out;
1049 }
1050 /* make one last check to be sure that the indicated RU didn't get
1051 * reconstructed while we were waiting for something else to happen.
1052 * This is unfortunate in that it causes us to make this check twice
1053 * in the normal case. Might want to make some attempt to re-work
1054 * this so that we only do this check if we've definitely blocked on
1055 * one of the above checks. When this condition is detected, we may
1056 * have just created a bogus status entry, which we need to delete. */
1057 if (rf_CheckRUReconstructed(raidPtr->reconControl[row]->reconMap, ctrl->rbuf->failedDiskSectorOffset)) {
1058 Dprintf2("RECON: Skipping psid %ld ru %d: prior recon after stall\n", psid, which_ru);
1059 if (created)
1060 rf_PSStatusDelete(raidPtr, raidPtr->reconControl[row]->pssTable, pssPtr);
1061 rf_CauseReconEvent(raidPtr, row, col, NULL, RF_REVENT_SKIP);
1062 goto out;
1063 }
1064 /* found something to read. issue the I/O */
1065 Dprintf5("RECON: Read for psid %ld on row %d col %d offset %ld buf %lx\n",
1066 psid, row, col, ctrl->diskOffset, ctrl->rbuf->buffer);
1067 RF_ETIMER_STOP(raidPtr->recon_tracerecs[col].recon_timer);
1068 RF_ETIMER_EVAL(raidPtr->recon_tracerecs[col].recon_timer);
1069 raidPtr->recon_tracerecs[col].specific.recon.recon_start_to_fetch_us =
1070 RF_ETIMER_VAL_US(raidPtr->recon_tracerecs[col].recon_timer);
1071 RF_ETIMER_START(raidPtr->recon_tracerecs[col].recon_timer);
1072
1073 /* should be ok to use a NULL proc pointer here, all the bufs we use
1074 * should be in kernel space */
1075 req = rf_CreateDiskQueueData(RF_IO_TYPE_READ, ctrl->diskOffset, sectorsPerRU, ctrl->rbuf->buffer, psid, which_ru,
1076 ReconReadDoneProc, (void *) ctrl, NULL, &raidPtr->recon_tracerecs[col], (void *) raidPtr, 0, NULL);
1077
1078 RF_ASSERT(req); /* XXX -- fix this -- XXX */
1079
1080 ctrl->rbuf->arg = (void *) req;
1081 rf_DiskIOEnqueue(&raidPtr->Queues[row][col], req, RF_IO_RECON_PRIORITY);
1082 pssPtr->issued[col] = 1;
1083
1084 out:
1085 RF_UNLOCK_PSS_MUTEX(raidPtr, row, psid);
1086 return (0);
1087 }
1088
1089
1090 /*
1091 * given a parity stripe ID, we want to find out whether both the
1092 * current disk and the failed disk exist in that parity stripe. If
1093 * not, we want to skip this whole PS. If so, we want to find the
1094 * disk offset of the start of the PS on both the current disk and the
1095 * failed disk.
1096 *
1097 * this works by getting a list of disks comprising the indicated
1098 * parity stripe, and searching the list for the current and failed
1099 * disks. Once we've decided they both exist in the parity stripe, we
1100 * need to decide whether each is data or parity, so that we'll know
1101 * which mapping function to call to get the corresponding disk
1102 * offsets.
1103 *
1104 * this is kind of unpleasant, but doing it this way allows the
1105 * reconstruction code to use parity stripe IDs rather than physical
1106 * disks address to march through the failed disk, which greatly
1107 * simplifies a lot of code, as well as eliminating the need for a
1108 * reverse-mapping function. I also think it will execute faster,
1109 * since the calls to the mapping module are kept to a minimum.
1110 *
1111 * ASSUMES THAT THE STRIPE IDENTIFIER IDENTIFIES THE DISKS COMPRISING
1112 * THE STRIPE IN THE CORRECT ORDER */
1113
1114
1115 static int
1116 ComputePSDiskOffsets(
1117 RF_Raid_t * raidPtr, /* raid descriptor */
1118 RF_StripeNum_t psid, /* parity stripe identifier */
1119 RF_RowCol_t row, /* row and column of disk to find the offsets
1120 * for */
1121 RF_RowCol_t col,
1122 RF_SectorNum_t * outDiskOffset,
1123 RF_SectorNum_t * outFailedDiskSectorOffset,
1124 RF_RowCol_t * spRow, /* OUT: row,col of spare unit for failed unit */
1125 RF_RowCol_t * spCol,
1126 RF_SectorNum_t * spOffset)
1127 { /* OUT: offset into disk containing spare unit */
1128 RF_RaidLayout_t *layoutPtr = &raidPtr->Layout;
1129 RF_RowCol_t fcol = raidPtr->reconControl[row]->fcol;
1130 RF_RaidAddr_t sosRaidAddress; /* start-of-stripe */
1131 RF_RowCol_t *diskids;
1132 u_int i, j, k, i_offset, j_offset;
1133 RF_RowCol_t prow, pcol;
1134 int testcol, testrow;
1135 RF_RowCol_t stripe;
1136 RF_SectorNum_t poffset;
1137 char i_is_parity = 0, j_is_parity = 0;
1138 RF_RowCol_t stripeWidth = layoutPtr->numDataCol + layoutPtr->numParityCol;
1139
1140 /* get a listing of the disks comprising that stripe */
1141 sosRaidAddress = rf_ParityStripeIDToRaidAddress(layoutPtr, psid);
1142 (layoutPtr->map->IdentifyStripe) (raidPtr, sosRaidAddress, &diskids, &stripe);
1143 RF_ASSERT(diskids);
1144
1145 /* reject this entire parity stripe if it does not contain the
1146 * indicated disk or it does not contain the failed disk */
1147 if (row != stripe)
1148 goto skipit;
1149 for (i = 0; i < stripeWidth; i++) {
1150 if (col == diskids[i])
1151 break;
1152 }
1153 if (i == stripeWidth)
1154 goto skipit;
1155 for (j = 0; j < stripeWidth; j++) {
1156 if (fcol == diskids[j])
1157 break;
1158 }
1159 if (j == stripeWidth) {
1160 goto skipit;
1161 }
1162 /* find out which disk the parity is on */
1163 (layoutPtr->map->MapParity) (raidPtr, sosRaidAddress, &prow, &pcol, &poffset, RF_DONT_REMAP);
1164
1165 /* find out if either the current RU or the failed RU is parity */
1166 /* also, if the parity occurs in this stripe prior to the data and/or
1167 * failed col, we need to decrement i and/or j */
1168 for (k = 0; k < stripeWidth; k++)
1169 if (diskids[k] == pcol)
1170 break;
1171 RF_ASSERT(k < stripeWidth);
1172 i_offset = i;
1173 j_offset = j;
1174 if (k < i)
1175 i_offset--;
1176 else
1177 if (k == i) {
1178 i_is_parity = 1;
1179 i_offset = 0;
1180 } /* set offsets to zero to disable multiply
1181 * below */
1182 if (k < j)
1183 j_offset--;
1184 else
1185 if (k == j) {
1186 j_is_parity = 1;
1187 j_offset = 0;
1188 }
1189 /* at this point, [ij]_is_parity tells us whether the [current,failed]
1190 * disk is parity at the start of this RU, and, if data, "[ij]_offset"
1191 * tells us how far into the stripe the [current,failed] disk is. */
1192
1193 /* call the mapping routine to get the offset into the current disk,
1194 * repeat for failed disk. */
1195 if (i_is_parity)
1196 layoutPtr->map->MapParity(raidPtr, sosRaidAddress + i_offset * layoutPtr->sectorsPerStripeUnit, &testrow, &testcol, outDiskOffset, RF_DONT_REMAP);
1197 else
1198 layoutPtr->map->MapSector(raidPtr, sosRaidAddress + i_offset * layoutPtr->sectorsPerStripeUnit, &testrow, &testcol, outDiskOffset, RF_DONT_REMAP);
1199
1200 RF_ASSERT(row == testrow && col == testcol);
1201
1202 if (j_is_parity)
1203 layoutPtr->map->MapParity(raidPtr, sosRaidAddress + j_offset * layoutPtr->sectorsPerStripeUnit, &testrow, &testcol, outFailedDiskSectorOffset, RF_DONT_REMAP);
1204 else
1205 layoutPtr->map->MapSector(raidPtr, sosRaidAddress + j_offset * layoutPtr->sectorsPerStripeUnit, &testrow, &testcol, outFailedDiskSectorOffset, RF_DONT_REMAP);
1206 RF_ASSERT(row == testrow && fcol == testcol);
1207
1208 /* now locate the spare unit for the failed unit */
1209 if (layoutPtr->map->flags & RF_DISTRIBUTE_SPARE) {
1210 if (j_is_parity)
1211 layoutPtr->map->MapParity(raidPtr, sosRaidAddress + j_offset * layoutPtr->sectorsPerStripeUnit, spRow, spCol, spOffset, RF_REMAP);
1212 else
1213 layoutPtr->map->MapSector(raidPtr, sosRaidAddress + j_offset * layoutPtr->sectorsPerStripeUnit, spRow, spCol, spOffset, RF_REMAP);
1214 } else {
1215 *spRow = raidPtr->reconControl[row]->spareRow;
1216 *spCol = raidPtr->reconControl[row]->spareCol;
1217 *spOffset = *outFailedDiskSectorOffset;
1218 }
1219
1220 return (0);
1221
1222 skipit:
1223 Dprintf3("RECON: Skipping psid %ld: nothing needed from r%d c%d\n",
1224 psid, row, col);
1225 return (1);
1226 }
1227 /* this is called when a buffer has become ready to write to the replacement disk */
1228 static int
1229 IssueNextWriteRequest(raidPtr, row)
1230 RF_Raid_t *raidPtr;
1231 RF_RowCol_t row;
1232 {
1233 RF_RaidLayout_t *layoutPtr = &raidPtr->Layout;
1234 RF_SectorCount_t sectorsPerRU = layoutPtr->sectorsPerStripeUnit * layoutPtr->SUsPerRU;
1235 RF_RowCol_t fcol = raidPtr->reconControl[row]->fcol;
1236 RF_ReconBuffer_t *rbuf;
1237 RF_DiskQueueData_t *req;
1238
1239 rbuf = rf_GetFullReconBuffer(raidPtr->reconControl[row]);
1240 RF_ASSERT(rbuf); /* there must be one available, or we wouldn't
1241 * have gotten the event that sent us here */
1242 RF_ASSERT(rbuf->pssPtr);
1243
1244 rbuf->pssPtr->writeRbuf = rbuf;
1245 rbuf->pssPtr = NULL;
1246
1247 Dprintf7("RECON: New write (r %d c %d offs %d) for psid %ld ru %d (failed disk offset %ld) buf %lx\n",
1248 rbuf->spRow, rbuf->spCol, rbuf->spOffset, rbuf->parityStripeID,
1249 rbuf->which_ru, rbuf->failedDiskSectorOffset, rbuf->buffer);
1250 Dprintf6("RECON: new write psid %ld %02x %02x %02x %02x %02x\n",
1251 rbuf->parityStripeID, rbuf->buffer[0] & 0xff, rbuf->buffer[1] & 0xff,
1252 rbuf->buffer[2] & 0xff, rbuf->buffer[3] & 0xff, rbuf->buffer[4] & 0xff);
1253
1254 /* should be ok to use a NULL b_proc here b/c all addrs should be in
1255 * kernel space */
1256 req = rf_CreateDiskQueueData(RF_IO_TYPE_WRITE, rbuf->spOffset,
1257 sectorsPerRU, rbuf->buffer,
1258 rbuf->parityStripeID, rbuf->which_ru,
1259 ReconWriteDoneProc, (void *) rbuf, NULL,
1260 &raidPtr->recon_tracerecs[fcol],
1261 (void *) raidPtr, 0, NULL);
1262
1263 RF_ASSERT(req); /* XXX -- fix this -- XXX */
1264
1265 rbuf->arg = (void *) req;
1266 rf_DiskIOEnqueue(&raidPtr->Queues[rbuf->spRow][rbuf->spCol], req, RF_IO_RECON_PRIORITY);
1267
1268 return (0);
1269 }
1270
1271 /*
1272 * this gets called upon the completion of a reconstruction read
1273 * operation the arg is a pointer to the per-disk reconstruction
1274 * control structure for the process that just finished a read.
1275 *
1276 * called at interrupt context in the kernel, so don't do anything
1277 * illegal here.
1278 */
1279 static int
1280 ReconReadDoneProc(arg, status)
1281 void *arg;
1282 int status;
1283 {
1284 RF_PerDiskReconCtrl_t *ctrl = (RF_PerDiskReconCtrl_t *) arg;
1285 RF_Raid_t *raidPtr = ctrl->reconCtrl->reconDesc->raidPtr;
1286
1287 if (status) {
1288 /*
1289 * XXX
1290 */
1291 printf("Recon read failed!\n");
1292 RF_PANIC();
1293 }
1294 RF_ETIMER_STOP(raidPtr->recon_tracerecs[ctrl->col].recon_timer);
1295 RF_ETIMER_EVAL(raidPtr->recon_tracerecs[ctrl->col].recon_timer);
1296 raidPtr->recon_tracerecs[ctrl->col].specific.recon.recon_fetch_to_return_us =
1297 RF_ETIMER_VAL_US(raidPtr->recon_tracerecs[ctrl->col].recon_timer);
1298 RF_ETIMER_START(raidPtr->recon_tracerecs[ctrl->col].recon_timer);
1299
1300 rf_CauseReconEvent(raidPtr, ctrl->row, ctrl->col, NULL, RF_REVENT_READDONE);
1301 return (0);
1302 }
1303 /* this gets called upon the completion of a reconstruction write operation.
1304 * the arg is a pointer to the rbuf that was just written
1305 *
1306 * called at interrupt context in the kernel, so don't do anything illegal here.
1307 */
1308 static int
1309 ReconWriteDoneProc(arg, status)
1310 void *arg;
1311 int status;
1312 {
1313 RF_ReconBuffer_t *rbuf = (RF_ReconBuffer_t *) arg;
1314
1315 Dprintf2("Reconstruction completed on psid %ld ru %d\n", rbuf->parityStripeID, rbuf->which_ru);
1316 if (status) {
1317 printf("Recon write failed!\n"); /* fprintf(stderr,"Recon
1318 * write failed!\n"); */
1319 RF_PANIC();
1320 }
1321 rf_CauseReconEvent((RF_Raid_t *) rbuf->raidPtr, rbuf->row, rbuf->col, arg, RF_REVENT_WRITEDONE);
1322 return (0);
1323 }
1324
1325
1326 /*
1327 * computes a new minimum head sep, and wakes up anyone who needs to
1328 * be woken as a result
1329 */
1330 static void
1331 CheckForNewMinHeadSep(raidPtr, row, hsCtr)
1332 RF_Raid_t *raidPtr;
1333 RF_RowCol_t row;
1334 RF_HeadSepLimit_t hsCtr;
1335 {
1336 RF_ReconCtrl_t *reconCtrlPtr = raidPtr->reconControl[row];
1337 RF_HeadSepLimit_t new_min;
1338 RF_RowCol_t i;
1339 RF_CallbackDesc_t *p;
1340 RF_ASSERT(hsCtr >= reconCtrlPtr->minHeadSepCounter); /* from the definition
1341 * of a minimum */
1342
1343
1344 RF_LOCK_MUTEX(reconCtrlPtr->rb_mutex);
1345
1346 new_min = ~(1L << (8 * sizeof(long) - 1)); /* 0x7FFF....FFF */
1347 for (i = 0; i < raidPtr->numCol; i++)
1348 if (i != reconCtrlPtr->fcol) {
1349 if (reconCtrlPtr->perDiskInfo[i].headSepCounter < new_min)
1350 new_min = reconCtrlPtr->perDiskInfo[i].headSepCounter;
1351 }
1352 /* set the new minimum and wake up anyone who can now run again */
1353 if (new_min != reconCtrlPtr->minHeadSepCounter) {
1354 reconCtrlPtr->minHeadSepCounter = new_min;
1355 Dprintf1("RECON: new min head pos counter val is %ld\n", new_min);
1356 while (reconCtrlPtr->headSepCBList) {
1357 if (reconCtrlPtr->headSepCBList->callbackArg.v > new_min)
1358 break;
1359 p = reconCtrlPtr->headSepCBList;
1360 reconCtrlPtr->headSepCBList = p->next;
1361 p->next = NULL;
1362 rf_CauseReconEvent(raidPtr, p->row, p->col, NULL, RF_REVENT_HEADSEPCLEAR);
1363 rf_FreeCallbackDesc(p);
1364 }
1365
1366 }
1367 RF_UNLOCK_MUTEX(reconCtrlPtr->rb_mutex);
1368 }
1369
1370 /*
1371 * checks to see that the maximum head separation will not be violated
1372 * if we initiate a reconstruction I/O on the indicated disk.
1373 * Limiting the maximum head separation between two disks eliminates
1374 * the nasty buffer-stall conditions that occur when one disk races
1375 * ahead of the others and consumes all of the floating recon buffers.
1376 * This code is complex and unpleasant but it's necessary to avoid
1377 * some very nasty, albeit fairly rare, reconstruction behavior.
1378 *
1379 * returns non-zero if and only if we have to stop working on the
1380 * indicated disk due to a head-separation delay.
1381 */
1382 static int
1383 CheckHeadSeparation(
1384 RF_Raid_t * raidPtr,
1385 RF_PerDiskReconCtrl_t * ctrl,
1386 RF_RowCol_t row,
1387 RF_RowCol_t col,
1388 RF_HeadSepLimit_t hsCtr,
1389 RF_ReconUnitNum_t which_ru)
1390 {
1391 RF_ReconCtrl_t *reconCtrlPtr = raidPtr->reconControl[row];
1392 RF_CallbackDesc_t *cb, *p, *pt;
1393 int retval = 0;
1394
1395 /* if we're too far ahead of the slowest disk, stop working on this
1396 * disk until the slower ones catch up. We do this by scheduling a
1397 * wakeup callback for the time when the slowest disk has caught up.
1398 * We define "caught up" with 20% hysteresis, i.e. the head separation
1399 * must have fallen to at most 80% of the max allowable head
1400 * separation before we'll wake up.
1401 *
1402 */
1403 RF_LOCK_MUTEX(reconCtrlPtr->rb_mutex);
1404 if ((raidPtr->headSepLimit >= 0) &&
1405 ((ctrl->headSepCounter - reconCtrlPtr->minHeadSepCounter) > raidPtr->headSepLimit)) {
1406 Dprintf6("raid%d: RECON: head sep stall: row %d col %d hsCtr %ld minHSCtr %ld limit %ld\n",
1407 raidPtr->raidid, row, col, ctrl->headSepCounter,
1408 reconCtrlPtr->minHeadSepCounter,
1409 raidPtr->headSepLimit);
1410 cb = rf_AllocCallbackDesc();
1411 /* the minHeadSepCounter value we have to get to before we'll
1412 * wake up. build in 20% hysteresis. */
1413 cb->callbackArg.v = (ctrl->headSepCounter - raidPtr->headSepLimit + raidPtr->headSepLimit / 5);
1414 cb->row = row;
1415 cb->col = col;
1416 cb->next = NULL;
1417
1418 /* insert this callback descriptor into the sorted list of
1419 * pending head-sep callbacks */
1420 p = reconCtrlPtr->headSepCBList;
1421 if (!p)
1422 reconCtrlPtr->headSepCBList = cb;
1423 else
1424 if (cb->callbackArg.v < p->callbackArg.v) {
1425 cb->next = reconCtrlPtr->headSepCBList;
1426 reconCtrlPtr->headSepCBList = cb;
1427 } else {
1428 for (pt = p, p = p->next; p && (p->callbackArg.v < cb->callbackArg.v); pt = p, p = p->next);
1429 cb->next = p;
1430 pt->next = cb;
1431 }
1432 retval = 1;
1433 #if RF_RECON_STATS > 0
1434 ctrl->reconCtrl->reconDesc->hsStallCount++;
1435 #endif /* RF_RECON_STATS > 0 */
1436 }
1437 RF_UNLOCK_MUTEX(reconCtrlPtr->rb_mutex);
1438
1439 return (retval);
1440 }
1441 /*
1442 * checks to see if reconstruction has been either forced or blocked
1443 * by a user operation. if forced, we skip this RU entirely. else if
1444 * blocked, put ourselves on the wait list. else return 0.
1445 *
1446 * ASSUMES THE PSS MUTEX IS LOCKED UPON ENTRY
1447 */
1448 static int
1449 CheckForcedOrBlockedReconstruction(
1450 RF_Raid_t * raidPtr,
1451 RF_ReconParityStripeStatus_t * pssPtr,
1452 RF_PerDiskReconCtrl_t * ctrl,
1453 RF_RowCol_t row,
1454 RF_RowCol_t col,
1455 RF_StripeNum_t psid,
1456 RF_ReconUnitNum_t which_ru)
1457 {
1458 RF_CallbackDesc_t *cb;
1459 int retcode = 0;
1460
1461 if ((pssPtr->flags & RF_PSS_FORCED_ON_READ) || (pssPtr->flags & RF_PSS_FORCED_ON_WRITE))
1462 retcode = RF_PSS_FORCED_ON_WRITE;
1463 else
1464 if (pssPtr->flags & RF_PSS_RECON_BLOCKED) {
1465 Dprintf4("RECON: row %d col %d blocked at psid %ld ru %d\n", row, col, psid, which_ru);
1466 cb = rf_AllocCallbackDesc(); /* append ourselves to
1467 * the blockage-wait
1468 * list */
1469 cb->row = row;
1470 cb->col = col;
1471 cb->next = pssPtr->blockWaitList;
1472 pssPtr->blockWaitList = cb;
1473 retcode = RF_PSS_RECON_BLOCKED;
1474 }
1475 if (!retcode)
1476 pssPtr->flags |= RF_PSS_UNDER_RECON; /* mark this RU as under
1477 * reconstruction */
1478
1479 return (retcode);
1480 }
1481 /*
1482 * if reconstruction is currently ongoing for the indicated stripeID,
1483 * reconstruction is forced to completion and we return non-zero to
1484 * indicate that the caller must wait. If not, then reconstruction is
1485 * blocked on the indicated stripe and the routine returns zero. If
1486 * and only if we return non-zero, we'll cause the cbFunc to get
1487 * invoked with the cbArg when the reconstruction has completed.
1488 */
1489 int
1490 rf_ForceOrBlockRecon(raidPtr, asmap, cbFunc, cbArg)
1491 RF_Raid_t *raidPtr;
1492 RF_AccessStripeMap_t *asmap;
1493 void (*cbFunc) (RF_Raid_t *, void *);
1494 void *cbArg;
1495 {
1496 RF_RowCol_t row = asmap->physInfo->row; /* which row of the array
1497 * we're working on */
1498 RF_StripeNum_t stripeID = asmap->stripeID; /* the stripe ID we're
1499 * forcing recon on */
1500 RF_SectorCount_t sectorsPerRU = raidPtr->Layout.sectorsPerStripeUnit * raidPtr->Layout.SUsPerRU; /* num sects in one RU */
1501 RF_ReconParityStripeStatus_t *pssPtr; /* a pointer to the parity
1502 * stripe status structure */
1503 RF_StripeNum_t psid; /* parity stripe id */
1504 RF_SectorNum_t offset, fd_offset; /* disk offset, failed-disk
1505 * offset */
1506 RF_RowCol_t *diskids;
1507 RF_RowCol_t stripe;
1508 RF_ReconUnitNum_t which_ru; /* RU within parity stripe */
1509 RF_RowCol_t fcol, diskno, i;
1510 RF_ReconBuffer_t *new_rbuf; /* ptr to newly allocated rbufs */
1511 RF_DiskQueueData_t *req;/* disk I/O req to be enqueued */
1512 RF_CallbackDesc_t *cb;
1513 int created = 0, nPromoted;
1514
1515 psid = rf_MapStripeIDToParityStripeID(&raidPtr->Layout, stripeID, &which_ru);
1516
1517 RF_LOCK_PSS_MUTEX(raidPtr, row, psid);
1518
1519 pssPtr = rf_LookupRUStatus(raidPtr, raidPtr->reconControl[row]->pssTable, psid, which_ru, RF_PSS_CREATE | RF_PSS_RECON_BLOCKED, &created);
1520
1521 /* if recon is not ongoing on this PS, just return */
1522 if (!(pssPtr->flags & RF_PSS_UNDER_RECON)) {
1523 RF_UNLOCK_PSS_MUTEX(raidPtr, row, psid);
1524 return (0);
1525 }
1526 /* otherwise, we have to wait for reconstruction to complete on this
1527 * RU. */
1528 /* In order to avoid waiting for a potentially large number of
1529 * low-priority accesses to complete, we force a normal-priority (i.e.
1530 * not low-priority) reconstruction on this RU. */
1531 if (!(pssPtr->flags & RF_PSS_FORCED_ON_WRITE) && !(pssPtr->flags & RF_PSS_FORCED_ON_READ)) {
1532 DDprintf1("Forcing recon on psid %ld\n", psid);
1533 pssPtr->flags |= RF_PSS_FORCED_ON_WRITE; /* mark this RU as under
1534 * forced recon */
1535 pssPtr->flags &= ~RF_PSS_RECON_BLOCKED; /* clear the blockage
1536 * that we just set */
1537 fcol = raidPtr->reconControl[row]->fcol;
1538
1539 /* get a listing of the disks comprising the indicated stripe */
1540 (raidPtr->Layout.map->IdentifyStripe) (raidPtr, asmap->raidAddress, &diskids, &stripe);
1541 RF_ASSERT(row == stripe);
1542
1543 /* For previously issued reads, elevate them to normal
1544 * priority. If the I/O has already completed, it won't be
1545 * found in the queue, and hence this will be a no-op. For
1546 * unissued reads, allocate buffers and issue new reads. The
1547 * fact that we've set the FORCED bit means that the regular
1548 * recon procs will not re-issue these reqs */
1549 for (i = 0; i < raidPtr->Layout.numDataCol + raidPtr->Layout.numParityCol; i++)
1550 if ((diskno = diskids[i]) != fcol) {
1551 if (pssPtr->issued[diskno]) {
1552 nPromoted = rf_DiskIOPromote(&raidPtr->Queues[row][diskno], psid, which_ru);
1553 if (rf_reconDebug && nPromoted)
1554 printf("raid%d: promoted read from row %d col %d\n", raidPtr->raidid, row, diskno);
1555 } else {
1556 new_rbuf = rf_MakeReconBuffer(raidPtr, row, diskno, RF_RBUF_TYPE_FORCED); /* create new buf */
1557 ComputePSDiskOffsets(raidPtr, psid, row, diskno, &offset, &fd_offset,
1558 &new_rbuf->spRow, &new_rbuf->spCol, &new_rbuf->spOffset); /* find offsets & spare
1559 * location */
1560 new_rbuf->parityStripeID = psid; /* fill in the buffer */
1561 new_rbuf->which_ru = which_ru;
1562 new_rbuf->failedDiskSectorOffset = fd_offset;
1563 new_rbuf->priority = RF_IO_NORMAL_PRIORITY;
1564
1565 /* use NULL b_proc b/c all addrs
1566 * should be in kernel space */
1567 req = rf_CreateDiskQueueData(RF_IO_TYPE_READ, offset + which_ru * sectorsPerRU, sectorsPerRU, new_rbuf->buffer,
1568 psid, which_ru, (int (*) (void *, int)) ForceReconReadDoneProc, (void *) new_rbuf, NULL,
1569 NULL, (void *) raidPtr, 0, NULL);
1570
1571 RF_ASSERT(req); /* XXX -- fix this --
1572 * XXX */
1573
1574 new_rbuf->arg = req;
1575 rf_DiskIOEnqueue(&raidPtr->Queues[row][diskno], req, RF_IO_NORMAL_PRIORITY); /* enqueue the I/O */
1576 Dprintf3("raid%d: Issued new read req on row %d col %d\n", raidPtr->raidid, row, diskno);
1577 }
1578 }
1579 /* if the write is sitting in the disk queue, elevate its
1580 * priority */
1581 if (rf_DiskIOPromote(&raidPtr->Queues[row][fcol], psid, which_ru))
1582 printf("raid%d: promoted write to row %d col %d\n",
1583 raidPtr->raidid, row, fcol);
1584 }
1585 /* install a callback descriptor to be invoked when recon completes on
1586 * this parity stripe. */
1587 cb = rf_AllocCallbackDesc();
1588 /* XXX the following is bogus.. These functions don't really match!!
1589 * GO */
1590 cb->callbackFunc = (void (*) (RF_CBParam_t)) cbFunc;
1591 cb->callbackArg.p = (void *) cbArg;
1592 cb->next = pssPtr->procWaitList;
1593 pssPtr->procWaitList = cb;
1594 DDprintf2("raid%d: Waiting for forced recon on psid %ld\n",
1595 raidPtr->raidid, psid);
1596
1597 RF_UNLOCK_PSS_MUTEX(raidPtr, row, psid);
1598 return (1);
1599 }
1600 /* called upon the completion of a forced reconstruction read.
1601 * all we do is schedule the FORCEDREADONE event.
1602 * called at interrupt context in the kernel, so don't do anything illegal here.
1603 */
1604 static void
1605 ForceReconReadDoneProc(arg, status)
1606 void *arg;
1607 int status;
1608 {
1609 RF_ReconBuffer_t *rbuf = arg;
1610
1611 if (status) {
1612 printf("Forced recon read failed!\n"); /* fprintf(stderr,"Forced
1613 * recon read
1614 * failed!\n"); */
1615 RF_PANIC();
1616 }
1617 rf_CauseReconEvent((RF_Raid_t *) rbuf->raidPtr, rbuf->row, rbuf->col, (void *) rbuf, RF_REVENT_FORCEDREADDONE);
1618 }
1619 /* releases a block on the reconstruction of the indicated stripe */
1620 int
1621 rf_UnblockRecon(raidPtr, asmap)
1622 RF_Raid_t *raidPtr;
1623 RF_AccessStripeMap_t *asmap;
1624 {
1625 RF_RowCol_t row = asmap->origRow;
1626 RF_StripeNum_t stripeID = asmap->stripeID;
1627 RF_ReconParityStripeStatus_t *pssPtr;
1628 RF_ReconUnitNum_t which_ru;
1629 RF_StripeNum_t psid;
1630 int created = 0;
1631 RF_CallbackDesc_t *cb;
1632
1633 psid = rf_MapStripeIDToParityStripeID(&raidPtr->Layout, stripeID, &which_ru);
1634 RF_LOCK_PSS_MUTEX(raidPtr, row, psid);
1635 pssPtr = rf_LookupRUStatus(raidPtr, raidPtr->reconControl[row]->pssTable, psid, which_ru, RF_PSS_NONE, &created);
1636
1637 /* When recon is forced, the pss desc can get deleted before we get
1638 * back to unblock recon. But, this can _only_ happen when recon is
1639 * forced. It would be good to put some kind of sanity check here, but
1640 * how to decide if recon was just forced or not? */
1641 if (!pssPtr) {
1642 /* printf("Warning: no pss descriptor upon unblock on psid %ld
1643 * RU %d\n",psid,which_ru); */
1644 if (rf_reconDebug || rf_pssDebug)
1645 printf("Warning: no pss descriptor upon unblock on psid %ld RU %d\n", (long) psid, which_ru);
1646 goto out;
1647 }
1648 pssPtr->blockCount--;
1649 Dprintf3("raid%d: unblocking recon on psid %ld: blockcount is %d\n",
1650 raidPtr->raidid, psid, pssPtr->blockCount);
1651 if (pssPtr->blockCount == 0) { /* if recon blockage has been released */
1652
1653 /* unblock recon before calling CauseReconEvent in case
1654 * CauseReconEvent causes us to try to issue a new read before
1655 * returning here. */
1656 pssPtr->flags &= ~RF_PSS_RECON_BLOCKED;
1657
1658
1659 while (pssPtr->blockWaitList) {
1660 /* spin through the block-wait list and
1661 release all the waiters */
1662 cb = pssPtr->blockWaitList;
1663 pssPtr->blockWaitList = cb->next;
1664 cb->next = NULL;
1665 rf_CauseReconEvent(raidPtr, cb->row, cb->col, NULL, RF_REVENT_BLOCKCLEAR);
1666 rf_FreeCallbackDesc(cb);
1667 }
1668 if (!(pssPtr->flags & RF_PSS_UNDER_RECON)) {
1669 /* if no recon was requested while recon was blocked */
1670 rf_PSStatusDelete(raidPtr, raidPtr->reconControl[row]->pssTable, pssPtr);
1671 }
1672 }
1673 out:
1674 RF_UNLOCK_PSS_MUTEX(raidPtr, row, psid);
1675 return (0);
1676 }
1677