tfixarenas.c - plan9port - [fork] Plan 9 from user space
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tfixarenas.c (40556B)
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1 /*
2 * Check and fix an arena partition.
3 *
4 * This is a lot grittier than the rest of Venti because
5 * it can't just give up if a byte here or there is wrong.
6 *
7 * The rule here (hopefully followed!) is that block corruption
8 * only ever has a local effect -- there are no blocks that you
9 * can wipe out that will cause large portions of
10 * uncorrupted data blocks to be useless.
11 */
12
13 #include "stdinc.h"
14 #include "dat.h"
15 #include "fns.h"
16 #include "whack.h"
17
18 #define ROUNDUP(x,n) (((x)+(n)-1)&~((n)-1))
19
20 #pragma varargck type "z" uvlong
21 #pragma varargck type "z" vlong
22 #pragma varargck type "t" uint
23
24 enum
25 {
26 K = 1024,
27 M = 1024*1024,
28 G = 1024*1024*1024,
29
30 Block = 4096,
31 };
32
33 int debugsha1;
34
35 int verbose;
36 Part *part;
37 char *file;
38 char *basename;
39 char *dumpbase;
40 int fix;
41 int badreads;
42 int unseal;
43 uchar zero[MaxDiskBlock];
44
45 Arena lastarena;
46 ArenaPart ap;
47 uvlong arenasize;
48 int nbadread;
49 int nbad;
50 uvlong partend;
51 void checkarena(vlong, int);
52
53 void
54 usage(void)
55 {
56 fprint(2, "usage: fixarenas [-fv] [-a arenasize] [-b blocksize] file [ranges]\n");
57 threadexitsall(0);
58 }
59
60 /*
61 * Format number in simplest way that is okay with unittoull.
62 */
63 static int
64 zfmt(Fmt *fmt)
65 {
66 vlong x;
67
68 x = va_arg(fmt->args, vlong);
69 if(x == 0)
70 return fmtstrcpy(fmt, "0");
71 if(x%G == 0)
72 return fmtprint(fmt, "%lldG", x/G);
73 if(x%M == 0)
74 return fmtprint(fmt, "%lldM", x/M);
75 if(x%K == 0)
76 return fmtprint(fmt, "%lldK", x/K);
77 return fmtprint(fmt, "%lld", x);
78 }
79
80 /*
81 * Format time like ctime without newline.
82 */
83 static int
84 tfmt(Fmt *fmt)
85 {
86 uint t;
87 char buf[30];
88
89 t = va_arg(fmt->args, uint);
90 strcpy(buf, ctime(t));
91 buf[28] = 0;
92 return fmtstrcpy(fmt, buf);
93 }
94
95 /*
96 * Coalesce messages about unreadable sectors into larger ranges.
97 * bad(0, 0) flushes the buffer.
98 */
99 static void
100 bad(char *msg, vlong o, int len)
101 {
102 static vlong lb0, lb1;
103 static char *lmsg;
104
105 if(msg == nil)
106 msg = lmsg;
107 if(o == -1){
108 lmsg = nil;
109 lb0 = 0;
110 lb1 = 0;
111 return;
112 }
113 if(lb1 != o || (msg && lmsg && strcmp(msg, lmsg) != 0)){
114 if(lb0 != lb1)
115 print("%s %#llux+%#llux (%,lld+%,lld)\n",
116 lmsg, lb0, lb1-lb0, lb0, lb1-lb0);
117 lb0 = o;
118 }
119 lmsg = msg;
120 lb1 = o+len;
121 }
122
123 /*
124 * Read in the len bytes of data at the offset. If can't for whatever reason,
125 * fill it with garbage but print an error.
126 */
127 static uchar*
128 readdisk(uchar *buf, vlong offset, int len)
129 {
130 int i, j, k, n;
131
132 if(offset >= partend){
133 memset(buf, 0xFB, len);
134 return buf;
135 }
136
137 if(offset+len > partend){
138 memset(buf, 0xFB, len);
139 len = partend - offset;
140 }
141
142 if(readpart(part, offset, buf, len) >= 0)
143 return buf;
144
145 /*
146 * The read failed. Clear the buffer to nonsense, and
147 * then try reading in smaller pieces. If that fails,
148 * read in even smaller pieces. And so on down to sectors.
149 */
150 memset(buf, 0xFD, len);
151 for(i=0; i<len; i+=64*K){
152 n = 64*K;
153 if(i+n > len)
154 n = len-i;
155 if(readpart(part, offset+i, buf+i, n) >= 0)
156 continue;
157 for(j=i; j<len && j<i+64*K; j+=4*K){
158 n = 4*K;
159 if(j+n > len)
160 n = len-j;
161 if(readpart(part, offset+j, buf+j, n) >= 0)
162 continue;
163 for(k=j; k<len && k<j+4*K; k+=512){
164 if(readpart(part, offset+k, buf+k, 512) >= 0)
165 continue;
166 bad("disk read failed at", k, 512);
167 badreads++;
168 }
169 }
170 }
171 bad(nil, 0, 0);
172 return buf;
173 }
174
175 /*
176 * Buffer to support running SHA1 hash of the disk.
177 */
178 typedef struct Shabuf Shabuf;
179 struct Shabuf
180 {
181 int fd;
182 vlong offset;
183 DigestState state;
184 int rollback;
185 vlong r0;
186 DigestState *hist;
187 int nhist;
188 };
189
190 void
191 sbdebug(Shabuf *sb, char *file)
192 {
193 int fd;
194
195 if(sb->fd > 0){
196 close(sb->fd);
197 sb->fd = 0;
198 }
199 if((fd = create(file, OWRITE, 0666)) < 0)
200 return;
201 if(fd == 0){
202 fd = dup(fd, -1);
203 close(0);
204 }
205 sb->fd = fd;
206 }
207
208 void
209 sbupdate(Shabuf *sb, uchar *p, vlong offset, int len)
210 {
211 int n, x;
212 vlong o;
213
214 if(sb->rollback && !sb->hist){
215 sb->r0 = offset;
216 sb->nhist = 1;
217 sb->hist = vtmalloc(sb->nhist*sizeof *sb->hist);
218 memset(sb->hist, 0, sizeof sb->hist[0]);
219 }
220 if(sb->r0 == 0)
221 sb->r0 = offset;
222
223 if(sb->offset < offset || sb->offset >= offset+len){
224 if(0) print("sbupdate %p %#llux+%d but offset=%#llux\n",
225 p, offset, len, sb->offset);
226 return;
227 }
228 x = sb->offset - offset;
229 if(0) print("sbupdate %p %#llux+%d skip %d\n",
230 sb, offset, len, x);
231 if(x){
232 p += x;
233 offset += x;
234 len -= x;
235 }
236 assert(sb->offset == offset);
237
238 if(sb->fd > 0)
239 pwrite(sb->fd, p, len, offset - sb->r0);
240
241 if(!sb->rollback){
242 sha1(p, len, nil, &sb->state);
243 sb->offset += len;
244 return;
245 }
246
247 /* save state every 4M so we can roll back quickly */
248 o = offset - sb->r0;
249 while(len > 0){
250 n = 4*M - o%(4*M);
251 if(n > len)
252 n = len;
253 sha1(p, n, nil, &sb->state);
254 sb->offset += n;
255 o += n;
256 p += n;
257 len -= n;
258 if(o%(4*M) == 0){
259 x = o/(4*M);
260 if(x >= sb->nhist){
261 if(x != sb->nhist)
262 print("oops! x=%d nhist=%d\n", x, sb->nhist);
263 sb->nhist += 32;
264 sb->hist = vtrealloc(sb->hist, sb->nhist*sizeof *sb->hist);
265 }
266 sb->hist[x] = sb->state;
267 }
268 }
269 }
270
271 void
272 sbdiskhash(Shabuf *sb, vlong eoffset)
273 {
274 static uchar dbuf[4*M];
275 int n;
276
277 while(sb->offset < eoffset){
278 n = sizeof dbuf;
279 if(sb->offset+n > eoffset)
280 n = eoffset - sb->offset;
281 readdisk(dbuf, sb->offset, n);
282 sbupdate(sb, dbuf, sb->offset, n);
283 }
284 }
285
286 void
287 sbrollback(Shabuf *sb, vlong offset)
288 {
289 int x;
290 vlong o;
291 Dir d;
292
293 if(!sb->rollback || !sb->r0){
294 print("cannot rollback sha\n");
295 return;
296 }
297 if(offset >= sb->offset)
298 return;
299 o = offset - sb->r0;
300 x = o/(4*M);
301 if(x >= sb->nhist){
302 print("cannot rollback sha\n");
303 return;
304 }
305 sb->state = sb->hist[x];
306 sb->offset = sb->r0 + x*4*M;
307 assert(sb->offset <= offset);
308
309 if(sb->fd > 0){
310 nulldir(&d);
311 d.length = sb->offset - sb->r0;
312 dirfwstat(sb->fd, &d);
313 }
314 }
315
316 void
317 sbscore(Shabuf *sb, uchar *score)
318 {
319 if(sb->hist){
320 free(sb->hist);
321 sb->hist = nil;
322 }
323 sha1(nil, 0, score, &sb->state);
324 }
325
326 /*
327 * If we're fixing arenas, then editing this memory edits the disk!
328 * It will be written back out as new data is paged in.
329 */
330 uchar buf[4*M];
331 uchar sbuf[4*M];
332 vlong bufoffset;
333 int buflen;
334
335 static void pageout(void);
336 static uchar*
337 pagein(vlong offset, int len)
338 {
339 pageout();
340 if(offset >= partend){
341 memset(buf, 0xFB, sizeof buf);
342 return buf;
343 }
344
345 if(offset+len > partend){
346 memset(buf, 0xFB, sizeof buf);
347 len = partend - offset;
348 }
349 bufoffset = offset;
350 buflen = len;
351 readdisk(buf, offset, len);
352 memmove(sbuf, buf, len);
353 return buf;
354 }
355
356 static void
357 pageout(void)
358 {
359 if(buflen==0 || !fix || memcmp(buf, sbuf, buflen) == 0){
360 buflen = 0;
361 return;
362 }
363 if(writepart(part, bufoffset, buf, buflen) < 0)
364 print("disk write failed at %#llux+%#ux (%,lld+%,d)\n",
365 bufoffset, buflen, bufoffset, buflen);
366 buflen = 0;
367 }
368
369 static void
370 zerorange(vlong offset, int len)
371 {
372 int i;
373 vlong ooff;
374 int olen;
375 enum { MinBlock = 4*K, MaxBlock = 8*K };
376
377 if(0)
378 if(bufoffset <= offset && offset+len <= bufoffset+buflen){
379 memset(buf+(offset-bufoffset), 0, len);
380 return;
381 }
382
383 ooff = bufoffset;
384 olen = buflen;
385
386 i = offset%MinBlock;
387 if(i+len < MaxBlock){
388 pagein(offset-i, (len+MinBlock-1)&~(MinBlock-1));
389 memset(buf+i, 0, len);
390 }else{
391 pagein(offset-i, MaxBlock);
392 memset(buf+i, 0, MaxBlock-i);
393 offset += MaxBlock-i;
394 len -= MaxBlock-i;
395 while(len >= MaxBlock){
396 pagein(offset, MaxBlock);
397 memset(buf, 0, MaxBlock);
398 offset += MaxBlock;
399 len -= MaxBlock;
400 }
401 pagein(offset, (len+MinBlock-1)&~(MinBlock-1));
402 memset(buf, 0, len);
403 }
404 pagein(ooff, olen);
405 }
406
407 /*
408 * read/write integers
409 *
410 static void
411 p16(uchar *p, u16int u)
412 {
413 p[0] = (u>>8) & 0xFF;
414 p[1] = u & 0xFF;
415 }
416 */
417
418 static u16int
419 u16(uchar *p)
420 {
421 return (p[0]<<8)|p[1];
422 }
423
424 static void
425 p32(uchar *p, u32int u)
426 {
427 p[0] = (u>>24) & 0xFF;
428 p[1] = (u>>16) & 0xFF;
429 p[2] = (u>>8) & 0xFF;
430 p[3] = u & 0xFF;
431 }
432
433 static u32int
434 u32(uchar *p)
435 {
436 return (p[0]<<24)|(p[1]<<16)|(p[2]<<8)|p[3];
437 }
438
439 /*
440 static void
441 p64(uchar *p, u64int u)
442 {
443 p32(p, u>>32);
444 p32(p, u);
445 }
446 */
447
448 static u64int
449 u64(uchar *p)
450 {
451 return ((u64int)u32(p)<<32) | u32(p+4);
452 }
453
454 static int
455 vlongcmp(const void *va, const void *vb)
456 {
457 vlong a, b;
458
459 a = *(vlong*)va;
460 b = *(vlong*)vb;
461 if(a < b)
462 return -1;
463 if(b > a)
464 return 1;
465 return 0;
466 }
467
468 /* D and S are in draw.h */
469 #define D VD
470 #define S VS
471
472 enum
473 {
474 D = 0x10000,
475 Z = 0x20000,
476 S = 0x30000,
477 T = 0x40000,
478 N = 0xFFFF
479 };
480 typedef struct Info Info;
481 struct Info
482 {
483 int len;
484 char *name;
485 };
486
487 Info partinfo[] = {
488 4, "magic",
489 D|4, "version",
490 Z|4, "blocksize",
491 4, "arenabase",
492 0
493 };
494
495 Info headinfo4[] = {
496 4, "magic",
497 D|4, "version",
498 S|ANameSize, "name",
499 Z|4, "blocksize",
500 Z|8, "size",
501 0
502 };
503
504 Info headinfo5[] = {
505 4, "magic",
506 D|4, "version",
507 S|ANameSize, "name",
508 Z|4, "blocksize",
509 Z|8, "size",
510 4, "clumpmagic",
511 0
512 };
513
514 Info tailinfo4[] = {
515 4, "magic",
516 D|4, "version",
517 S|ANameSize, "name",
518 D|4, "clumps",
519 D|4, "cclumps",
520 T|4, "ctime",
521 T|4, "wtime",
522 D|8, "used",
523 D|8, "uncsize",
524 1, "sealed",
525 0
526 };
527
528 Info tailinfo4a[] = {
529 /* tailinfo 4 */
530 4, "magic",
531 D|4, "version",
532 S|ANameSize, "name",
533 D|4, "clumps",
534 D|4, "cclumps",
535 T|4, "ctime",
536 T|4, "wtime",
537 D|8, "used",
538 D|8, "uncsize",
539 1, "sealed",
540
541 /* mem stats */
542 1, "extension",
543 D|4, "mem.clumps",
544 D|4, "mem.cclumps",
545 D|8, "mem.used",
546 D|8, "mem.uncsize",
547 1, "mem.sealed",
548 0
549 };
550
551 Info tailinfo5[] = {
552 4, "magic",
553 D|4, "version",
554 S|ANameSize, "name",
555 D|4, "clumps",
556 D|4, "cclumps",
557 T|4, "ctime",
558 T|4, "wtime",
559 4, "clumpmagic",
560 D|8, "used",
561 D|8, "uncsize",
562 1, "sealed",
563 0
564 };
565
566 Info tailinfo5a[] = {
567 /* tailinfo 5 */
568 4, "magic",
569 D|4, "version",
570 S|ANameSize, "name",
571 D|4, "clumps",
572 D|4, "cclumps",
573 T|4, "ctime",
574 T|4, "wtime",
575 4, "clumpmagic",
576 D|8, "used",
577 D|8, "uncsize",
578 1, "sealed",
579
580 /* mem stats */
581 1, "extension",
582 D|4, "mem.clumps",
583 D|4, "mem.cclumps",
584 D|8, "mem.used",
585 D|8, "mem.uncsize",
586 1, "mem.sealed",
587 0
588 };
589
590 void
591 showdiffs(uchar *want, uchar *have, int len, Info *info)
592 {
593 int n;
594
595 while(len > 0 && (n=info->len&N) > 0){
596 if(memcmp(have, want, n) != 0){
597 switch(info->len){
598 case 1:
599 print("\t%s: correct=%d disk=%d\n",
600 info->name, *want, *have);
601 break;
602 case 4:
603 print("\t%s: correct=%#ux disk=%#ux\n",
604 info->name, u32(want), u32(have));
605 break;
606 case D|4:
607 print("\t%s: correct=%,ud disk=%,ud\n",
608 info->name, u32(want), u32(have));
609 break;
610 case T|4:
611 print("\t%s: correct=%t\n\t\tdisk=%t\n",
612 info->name, u32(want), u32(have));
613 break;
614 case Z|4:
615 print("\t%s: correct=%z disk=%z\n",
616 info->name, (uvlong)u32(want), (uvlong)u32(have));
617 break;
618 case D|8:
619 print("\t%s: correct=%,lld disk=%,lld\n",
620 info->name, u64(want), u64(have));
621 break;
622 case Z|8:
623 print("\t%s: correct=%z disk=%z\n",
624 info->name, u64(want), u64(have));
625 break;
626 case S|ANameSize:
627 print("\t%s: correct=%s disk=%.*s\n",
628 info->name, (char*)want,
629 utfnlen((char*)have, ANameSize-1),
630 (char*)have);
631 break;
632 default:
633 print("\t%s: correct=%.*H disk=%.*H\n",
634 info->name, n, want, n, have);
635 break;
636 }
637 }
638 have += n;
639 want += n;
640 len -= n;
641 info++;
642 }
643 if(len > 0 && memcmp(have, want, len) != 0){
644 if(memcmp(want, zero, len) != 0)
645 print("!!\textra want data in showdiffs (bug in fixarenas)\n");
646 else
647 print("\tnon-zero data on disk after structure\n");
648 if(verbose > 1){
649 print("want: %.*H\n", len, want);
650 print("have: %.*H\n", len, have);
651 }
652 }
653 }
654
655 /*
656 * Does part begin with an arena?
657 */
658 int
659 isonearena(void)
660 {
661 return u32(pagein(0, Block)) == ArenaHeadMagic;
662 }
663
664 static int tabsizes[] = { 16*1024, 64*1024, 512*1024, 768*1024, };
665 /*
666 * Poke around on the disk to guess what the ArenaPart numbers are.
667 */
668 void
669 guessgeometry(void)
670 {
671 int i, j, n, bestn, ndiff, nhead, ntail;
672 uchar *p, *ep, *sp;
673 u64int diff[100], head[20], tail[20];
674 u64int offset, bestdiff;
675
676 ap.version = ArenaPartVersion;
677
678 if(arenasize == 0 || ap.blocksize == 0){
679 /*
680 * The ArenaPart block at offset PartBlank may be corrupt or just wrong.
681 * Instead, look for the individual arena headers and tails, which there
682 * are many of, and once we've seen enough, infer the spacing.
683 *
684 * Of course, nothing in the file format requires that arenas be evenly
685 * spaced, but fmtarenas always does that for us.
686 */
687 nhead = 0;
688 ntail = 0;
689 for(offset=PartBlank; offset<partend; offset+=4*M){
690 p = pagein(offset, 4*M);
691 for(sp=p, ep=p+4*M; p<ep; p+=K){
692 if(u32(p) == ArenaHeadMagic && nhead < nelem(head)){
693 if(verbose)
694 print("arena head at %#llx\n", offset+(p-sp));
695 head[nhead++] = offset+(p-sp);
696 }
697 if(u32(p) == ArenaMagic && ntail < nelem(tail)){
698 tail[ntail++] = offset+(p-sp);
699 if(verbose)
700 print("arena tail at %#llx\n", offset+(p-sp));
701 }
702 }
703 if(nhead == nelem(head) && ntail == nelem(tail))
704 break;
705 }
706 if(nhead < 3 && ntail < 3)
707 sysfatal("too few intact arenas: %d heads, %d tails", nhead, ntail);
708
709 /*
710 * Arena size is likely the most common
711 * inter-head or inter-tail spacing.
712 */
713 ndiff = 0;
714 for(i=1; i<nhead; i++)
715 diff[ndiff++] = head[i] - head[i-1];
716 for(i=1; i<ntail; i++)
717 diff[ndiff++] = tail[i] - tail[i-1];
718 qsort(diff, ndiff, sizeof diff[0], vlongcmp);
719 bestn = 0;
720 bestdiff = 0;
721 for(i=1, n=1; i<=ndiff; i++, n++){
722 if(i==ndiff || diff[i] != diff[i-1]){
723 if(n > bestn){
724 bestn = n;
725 bestdiff = diff[i-1];
726 }
727 n = 0;
728 }
729 }
730 print("arena size likely %z (%d of %d)\n", bestdiff, bestn, ndiff);
731 if(arenasize != 0 && arenasize != bestdiff)
732 print("using user-specified size %z instead\n", arenasize);
733 else
734 arenasize = bestdiff;
735
736 /*
737 * The arena tail for an arena is arenasize-blocksize from the head.
738 */
739 ndiff = 0;
740 for(i=j=0; i<nhead && j<ntail; ){
741 if(tail[j] < head[i]){
742 j++;
743 continue;
744 }
745 if(tail[j] < head[i]+arenasize){
746 diff[ndiff++] = head[i]+arenasize - tail[j];
747 j++;
748 continue;
749 }
750 i++;
751 }
752 if(ndiff < 3)
753 sysfatal("too few intact arenas: %d head, tail pairs", ndiff);
754 qsort(diff, ndiff, sizeof diff[0], vlongcmp);
755 bestn = 0;
756 bestdiff = 0;
757 for(i=1, n=1; i<=ndiff; i++, n++){
758 if(i==ndiff || diff[i] != diff[i-1]){
759 if(n > bestn){
760 bestn = n;
761 bestdiff = diff[i-1];
762 }
763 n = 0;
764 }
765 }
766 print("block size likely %z (%d of %d)\n", bestdiff, bestn, ndiff);
767 if(ap.blocksize != 0 && ap.blocksize != bestdiff)
768 print("using user-specified size %z instead\n", (vlong)ap.blocksize);
769 else
770 ap.blocksize = bestdiff;
771 if(ap.blocksize == 0 || ap.blocksize&(ap.blocksize-1))
772 sysfatal("block size not a power of two");
773 if(ap.blocksize > MaxDiskBlock)
774 sysfatal("block size too big (max=%d)", MaxDiskBlock);
775
776 /*
777 * Use head/tail information to deduce arena base.
778 */
779 ndiff = 0;
780 for(i=0; i<nhead; i++)
781 diff[ndiff++] = head[i]%arenasize;
782 for(i=0; i<ntail; i++)
783 diff[ndiff++] = (tail[i]+ap.blocksize)%arenasize;
784 qsort(diff, ndiff, sizeof diff[0], vlongcmp);
785 bestn = 0;
786 bestdiff = 0;
787 for(i=1, n=1; i<=ndiff; i++, n++){
788 if(i==ndiff || diff[i] != diff[i-1]){
789 if(n > bestn){
790 bestn = n;
791 bestdiff = diff[i-1];
792 }
793 n = 0;
794 }
795 }
796 ap.arenabase = bestdiff;
797 }
798
799 ap.tabbase = ROUNDUP(PartBlank+HeadSize, ap.blocksize);
800 /*
801 * XXX pick up table, check arenabase.
802 * XXX pick up table, record base name.
803 */
804
805 /*
806 * Somewhat standard computation.
807 * Fmtarenas used to use 64k tab, now uses 512k tab.
808 */
809 if(ap.arenabase == 0){
810 print("trying standard arena bases...\n");
811 for(i=0; i<nelem(tabsizes); i++){
812 ap.arenabase = ROUNDUP(PartBlank+HeadSize+tabsizes[i], ap.blocksize);
813 p = pagein(ap.arenabase, Block);
814 if(u32(p) == ArenaHeadMagic)
815 break;
816 }
817 }
818 p = pagein(ap.arenabase, Block);
819 print("arena base likely %z%s\n", (vlong)ap.arenabase,
820 u32(p)!=ArenaHeadMagic ? " (but no arena head there)" : "");
821
822 ap.tabsize = ap.arenabase - ap.tabbase;
823 }
824
825 /*
826 * Check the arena partition blocks and then the arenas listed in range.
827 */
828 void
829 checkarenas(char *range)
830 {
831 char *s, *t;
832 int i, lo, hi, narena;
833 uchar dbuf[HeadSize];
834 uchar *p;
835
836 guessgeometry();
837
838 partend -= partend%ap.blocksize;
839
840 memset(dbuf, 0, sizeof dbuf);
841 packarenapart(&ap, dbuf);
842 p = pagein(PartBlank, Block);
843 if(memcmp(p, dbuf, HeadSize) != 0){
844 print("on-disk arena part superblock incorrect\n");
845 showdiffs(dbuf, p, HeadSize, partinfo);
846 }
847 memmove(p, dbuf, HeadSize);
848
849 narena = (partend-ap.arenabase + arenasize-1)/arenasize;
850 if(range == nil){
851 for(i=0; i<narena; i++)
852 checkarena(ap.arenabase+(vlong)i*arenasize, i);
853 }else if(strcmp(range, "none") == 0){
854 /* nothing */
855 }else{
856 /* parse, e.g., -4,8-9,10- */
857 for(s=range; *s; s=t){
858 t = strchr(s, ',');
859 if(t)
860 *t++ = 0;
861 else
862 t = s+strlen(s);
863 if(*s == '-')
864 lo = 0;
865 else
866 lo = strtol(s, &s, 0);
867 hi = lo;
868 if(*s == '-'){
869 s++;
870 if(*s == 0)
871 hi = narena-1;
872 else
873 hi = strtol(s, &s, 0);
874 }
875 if(*s != 0){
876 print("bad arena range: %s\n", s);
877 continue;
878 }
879 for(i=lo; i<=hi; i++)
880 checkarena(ap.arenabase+(vlong)i*arenasize, i);
881 }
882 }
883 }
884
885 /*
886 * Is there a clump here at p?
887 */
888 static int
889 isclump(uchar *p, Clump *cl, u32int *pmagic)
890 {
891 int n;
892 u32int magic;
893 uchar score[VtScoreSize], *bp;
894 Unwhack uw;
895 uchar ubuf[70*1024];
896
897 bp = p;
898 magic = u32(p);
899 if(magic == 0)
900 return 0;
901 p += U32Size;
902
903 cl->info.type = vtfromdisktype(*p);
904 if(cl->info.type == 0xFF)
905 return 0;
906 p++;
907 cl->info.size = u16(p);
908 p += U16Size;
909 cl->info.uncsize = u16(p);
910 if(cl->info.size > cl->info.uncsize)
911 return 0;
912 p += U16Size;
913 scorecp(cl->info.score, p);
914 p += VtScoreSize;
915 cl->encoding = *p;
916 p++;
917 cl->creator = u32(p);
918 p += U32Size;
919 cl->time = u32(p);
920 p += U32Size;
921
922 switch(cl->encoding){
923 case ClumpENone:
924 if(cl->info.size != cl->info.uncsize)
925 return 0;
926 scoremem(score, p, cl->info.size);
927 if(scorecmp(score, cl->info.score) != 0)
928 return 0;
929 break;
930 case ClumpECompress:
931 if(cl->info.size >= cl->info.uncsize)
932 return 0;
933 unwhackinit(&uw);
934 n = unwhack(&uw, ubuf, cl->info.uncsize, p, cl->info.size);
935 if(n != cl->info.uncsize)
936 return 0;
937 scoremem(score, ubuf, cl->info.uncsize);
938 if(scorecmp(score, cl->info.score) != 0)
939 return 0;
940 break;
941 default:
942 return 0;
943 }
944 p += cl->info.size;
945
946 /* it all worked out in the end */
947 *pmagic = magic;
948 return p - bp;
949 }
950
951 /*
952 * All ClumpInfos seen in this arena.
953 * Kept in binary tree so we can look up by score.
954 */
955 typedef struct Cit Cit;
956 struct Cit
957 {
958 int left;
959 int right;
960 vlong corrupt;
961 ClumpInfo ci;
962 };
963 Cit *cibuf;
964 int ciroot;
965 int ncibuf, mcibuf;
966
967 void
968 resetcibuf(void)
969 {
970 ncibuf = 0;
971 ciroot = -1;
972 }
973
974 int*
975 ltreewalk(int *p, uchar *score)
976 {
977 int i;
978
979 for(;;){
980 if(*p == -1)
981 return p;
982 i = scorecmp(cibuf[*p].ci.score, score);
983 if(i == 0)
984 return p;
985 if(i < 0)
986 p = &cibuf[*p].right;
987 else
988 p = &cibuf[*p].left;
989 }
990 }
991
992 void
993 addcibuf(ClumpInfo *ci, vlong corrupt)
994 {
995 Cit *cit;
996
997 if(ncibuf == mcibuf){
998 mcibuf += 131072;
999 cibuf = vtrealloc(cibuf, mcibuf*sizeof cibuf[0]);
1000 }
1001 cit = &cibuf[ncibuf];
1002 cit->ci = *ci;
1003 cit->left = -1;
1004 cit->right = -1;
1005 cit->corrupt = corrupt;
1006 if(!corrupt)
1007 *ltreewalk(&ciroot, ci->score) = ncibuf;
1008 ncibuf++;
1009 }
1010
1011 void
1012 addcicorrupt(vlong len)
1013 {
1014 static ClumpInfo zci;
1015
1016 addcibuf(&zci, len);
1017 }
1018
1019 int
1020 haveclump(uchar *score)
1021 {
1022 int i;
1023 int p;
1024
1025 p = ciroot;
1026 for(;;){
1027 if(p == -1)
1028 return 0;
1029 i = scorecmp(cibuf[p].ci.score, score);
1030 if(i == 0)
1031 return 1;
1032 if(i < 0)
1033 p = cibuf[p].right;
1034 else
1035 p = cibuf[p].left;
1036 }
1037 }
1038
1039 int
1040 matchci(ClumpInfo *ci, uchar *p)
1041 {
1042 if(ci->type != vtfromdisktype(p[0]))
1043 return 0;
1044 if(ci->size != u16(p+1))
1045 return 0;
1046 if(ci->uncsize != u16(p+3))
1047 return 0;
1048 if(scorecmp(ci->score, p+5) != 0)
1049 return 0;
1050 return 1;
1051 }
1052
1053 int
1054 sealedarena(uchar *p, int blocksize)
1055 {
1056 int v, n;
1057
1058 v = u32(p+4);
1059 switch(v){
1060 default:
1061 return 0;
1062 case ArenaVersion4:
1063 n = ArenaSize4;
1064 break;
1065 case ArenaVersion5:
1066 n = ArenaSize5;
1067 break;
1068 }
1069 if(p[n-1] != 1){
1070 print("arena tail says not sealed\n");
1071 return 0;
1072 }
1073 if(memcmp(p+n, zero, blocksize-VtScoreSize-n) != 0){
1074 print("arena tail followed by non-zero data\n");
1075 return 0;
1076 }
1077 if(memcmp(p+blocksize-VtScoreSize, zero, VtScoreSize) == 0){
1078 print("arena score zero\n");
1079 return 0;
1080 }
1081 return 1;
1082 }
1083
1084 int
1085 okayname(char *name, int n)
1086 {
1087 char buf[20];
1088
1089 if(nameok(name) < 0)
1090 return 0;
1091 sprint(buf, "%d", n);
1092 if(n == 0)
1093 buf[0] = 0;
1094 if(strlen(name) < strlen(buf)
1095 || strcmp(name+strlen(name)-strlen(buf), buf) != 0)
1096 return 0;
1097 return 1;
1098 }
1099
1100 int
1101 clumpinfocmp(ClumpInfo *a, ClumpInfo *b)
1102 {
1103 if(a->type != b->type)
1104 return a->type - b->type;
1105 if(a->size != b->size)
1106 return a->size - b->size;
1107 if(a->uncsize != b->uncsize)
1108 return a->uncsize - b->uncsize;
1109 return scorecmp(a->score, b->score);
1110 }
1111
1112 ClumpInfo*
1113 loadci(vlong offset, Arena *arena, int nci)
1114 {
1115 int i, j, per;
1116 uchar *p, *sp;
1117 ClumpInfo *bci, *ci;
1118
1119 per = arena->blocksize/ClumpInfoSize;
1120 bci = vtmalloc(nci*sizeof bci[0]);
1121 ci = bci;
1122 offset += arena->size - arena->blocksize;
1123 p = sp = nil;
1124 for(i=0; i<nci; i+=per){
1125 if(p == sp){
1126 sp = pagein(offset-4*M, 4*M);
1127 p = sp+4*M;
1128 }
1129 p -= arena->blocksize;
1130 offset -= arena->blocksize;
1131 for(j=0; j<per && i+j<nci; j++)
1132 unpackclumpinfo(ci++, p+j*ClumpInfoSize);
1133 }
1134 return bci;
1135 }
1136
1137 vlong
1138 writeci(vlong offset, Arena *arena, ClumpInfo *ci, int nci)
1139 {
1140 int i, j, per;
1141 uchar *p, *sp;
1142
1143 per = arena->blocksize/ClumpInfoSize;
1144 offset += arena->size - arena->blocksize;
1145 p = sp = nil;
1146 for(i=0; i<nci; i+=per){
1147 if(p == sp){
1148 sp = pagein(offset-4*M, 4*M);
1149 p = sp+4*M;
1150 }
1151 p -= arena->blocksize;
1152 offset -= arena->blocksize;
1153 memset(p, 0, arena->blocksize);
1154 for(j=0; j<per && i+j<nci; j++)
1155 packclumpinfo(ci++, p+j*ClumpInfoSize);
1156 }
1157 pageout();
1158 return offset;
1159 }
1160
1161 void
1162 loadarenabasics(vlong offset0, int anum, ArenaHead *head, Arena *arena)
1163 {
1164 char dname[ANameSize];
1165 static char lastbase[ANameSize];
1166 uchar *p;
1167 Arena oarena;
1168 ArenaHead ohead;
1169
1170 /*
1171 * Fmtarenas makes all arenas the same size
1172 * except the last, which may be smaller.
1173 * It uses the same block size for arenas as for
1174 * the arena partition blocks.
1175 */
1176 arena->size = arenasize;
1177 if(offset0+arena->size > partend)
1178 arena->size = partend - offset0;
1179 head->size = arena->size;
1180
1181 arena->blocksize = ap.blocksize;
1182 head->blocksize = arena->blocksize;
1183
1184 /*
1185 * Look for clump magic and name in head/tail blocks.
1186 * All the other info we will reconstruct just in case.
1187 */
1188 p = pagein(offset0, arena->blocksize);
1189 memset(&ohead, 0, sizeof ohead);
1190 if(unpackarenahead(&ohead, p) >= 0){
1191 head->version = ohead.version;
1192 head->clumpmagic = ohead.clumpmagic;
1193 if(okayname(ohead.name, anum))
1194 strcpy(head->name, ohead.name);
1195 }
1196
1197 p = pagein(offset0+arena->size-arena->blocksize,
1198 arena->blocksize);
1199 memset(&oarena, 0, sizeof oarena);
1200 if(unpackarena(&oarena, p) >= 0){
1201 arena->version = oarena.version;
1202 arena->clumpmagic = oarena.clumpmagic;
1203 if(okayname(oarena.name, anum))
1204 strcpy(arena->name, oarena.name);
1205 arena->diskstats.clumps = oarena.diskstats.clumps;
1206 print("old arena: sealed=%d\n", oarena.diskstats.sealed);
1207 arena->diskstats.sealed = oarena.diskstats.sealed;
1208 }
1209
1210 /* Head trumps arena. */
1211 if(head->version){
1212 arena->version = head->version;
1213 arena->clumpmagic = head->clumpmagic;
1214 }
1215 if(arena->version == 0)
1216 arena->version = ArenaVersion5;
1217 if(basename){
1218 if(anum == -1)
1219 snprint(arena->name, ANameSize, "%s", basename);
1220 else
1221 snprint(arena->name, ANameSize, "%s%d", basename, anum);
1222 }else if(lastbase[0])
1223 snprint(arena->name, ANameSize, "%s%d", lastbase, anum);
1224 else if(head->name[0])
1225 strcpy(arena->name, head->name);
1226 else if(arena->name[0] == 0)
1227 sysfatal("cannot determine base name for arena; use -n");
1228 strcpy(lastbase, arena->name);
1229 sprint(dname, "%d", anum);
1230 lastbase[strlen(lastbase)-strlen(dname)] = 0;
1231
1232 /* Was working in arena, now copy to head. */
1233 head->version = arena->version;
1234 memmove(head->name, arena->name, sizeof head->name);
1235 head->blocksize = arena->blocksize;
1236 head->size = arena->size;
1237 }
1238
1239 void
1240 shahead(Shabuf *sb, vlong offset0, ArenaHead *head)
1241 {
1242 uchar headbuf[MaxDiskBlock];
1243
1244 sb->offset = offset0;
1245 memset(headbuf, 0, sizeof headbuf);
1246 packarenahead(head, headbuf);
1247 sbupdate(sb, headbuf, offset0, head->blocksize);
1248 }
1249
1250 u32int
1251 newclumpmagic(int version)
1252 {
1253 u32int m;
1254
1255 if(version == ArenaVersion4)
1256 return _ClumpMagic;
1257 do{
1258 m = fastrand();
1259 }while(m==0 || m == _ClumpMagic);
1260 return m;
1261 }
1262
1263 /*
1264 * Poke around in the arena to find the clump data
1265 * and compute the relevant statistics.
1266 */
1267 void
1268 guessarena(vlong offset0, int anum, ArenaHead *head, Arena *arena,
1269 uchar *oldscore, uchar *score)
1270 {
1271 uchar dbuf[MaxDiskBlock];
1272 int needtozero, clumps, nb1, nb2, minclumps;
1273 int inbad, n, ncib, printed, sealing, smart;
1274 u32int magic;
1275 uchar *sp, *ep, *p;
1276 vlong boffset, eoffset, lastclumpend, leaked;
1277 vlong offset, toffset, totalcorrupt, v;
1278 Clump cl;
1279 ClumpInfo *bci, *ci, *eci, *xci;
1280 Cit *bcit, *cit, *ecit;
1281 Shabuf oldsha, newsha;
1282
1283 /*
1284 * We expect to find an arena, with data, between offset
1285 * and offset+arenasize. With any luck, the data starts at
1286 * offset+ap.blocksize. The blocks have variable size and
1287 * aren't padded at all, which doesn't give us any alignment
1288 * constraints. The blocks are compressed or high entropy,
1289 * but the headers are pretty low entropy (except the score):
1290 *
1291 * type[1] (range 0 thru 9, 13)
1292 * size[2]
1293 * uncsize[2] (<= size)
1294 *
1295 * so we can look for these. We check the scores as we go,
1296 * so we can't make any wrong turns. If we find ourselves
1297 * in a dead end, scan forward looking for a new start.
1298 */
1299
1300 resetcibuf();
1301 memset(head, 0, sizeof *head);
1302 memset(arena, 0, sizeof *arena);
1303 memset(oldscore, 0, VtScoreSize);
1304 memset(score, 0, VtScoreSize);
1305 memset(&oldsha, 0, sizeof oldsha);
1306 memset(&newsha, 0, sizeof newsha);
1307 newsha.rollback = 1;
1308
1309 if(0){
1310 sbdebug(&oldsha, "old.sha");
1311 sbdebug(&newsha, "new.sha");
1312 }
1313
1314 loadarenabasics(offset0, anum, head, arena);
1315
1316 /* start the clump hunt */
1317
1318 clumps = 0;
1319 totalcorrupt = 0;
1320 sealing = 1;
1321 boffset = offset0 + arena->blocksize;
1322 offset = boffset;
1323 eoffset = offset0+arena->size - arena->blocksize;
1324 toffset = eoffset;
1325 sp = pagein(offset0, 4*M);
1326
1327 if(arena->diskstats.sealed){
1328 oldsha.offset = offset0;
1329 sbupdate(&oldsha, sp, offset0, 4*M);
1330 }
1331 ep = sp+4*M;
1332 p = sp + (boffset - offset0);
1333 ncib = arena->blocksize / ClumpInfoSize; /* ci per block in index */
1334 lastclumpend = offset;
1335 nbad = 0;
1336 inbad = 0;
1337 needtozero = 0;
1338 minclumps = 0;
1339 while(offset < eoffset){
1340 /*
1341 * Shift buffer if we're running out of room.
1342 */
1343 if(p+70*K >= ep){
1344 /*
1345 * Start the post SHA1 buffer. By now we should know the
1346 * clumpmagic and arena version, so we can create a
1347 * correct head block to get things going.
1348 */
1349 if(sealing && fix && newsha.offset == 0){
1350 newsha.offset = offset0;
1351 if(arena->clumpmagic == 0){
1352 if(arena->version == 0)
1353 arena->version = ArenaVersion5;
1354 arena->clumpmagic = newclumpmagic(arena->version);
1355 }
1356 head->clumpmagic = arena->clumpmagic;
1357 shahead(&newsha, offset0, head);
1358 }
1359 n = 4*M-256*K;
1360 if(sealing && fix){
1361 sbdiskhash(&newsha, bufoffset);
1362 sbupdate(&newsha, buf, bufoffset, 4*M-256*K);
1363 }
1364 pagein(bufoffset+n, 4*M);
1365 p -= n;
1366 if(arena->diskstats.sealed)
1367 sbupdate(&oldsha, buf, bufoffset, 4*M);
1368 }
1369
1370 /*
1371 * Check for a clump at p, which is at offset in the disk.
1372 * Duplicate clumps happen in corrupted disks
1373 * (the same pattern gets written many times in a row)
1374 * and should never happen during regular use.
1375 */
1376 magic = 0;
1377 if((n = isclump(p, &cl, &magic)) > 0){
1378 /*
1379 * If we were in the middle of some corrupted data,
1380 * flush a warning about it and then add any clump
1381 * info blocks as necessary.
1382 */
1383 if(inbad){
1384 inbad = 0;
1385 v = offset-lastclumpend;
1386 if(needtozero){
1387 zerorange(lastclumpend, v);
1388 sbrollback(&newsha, lastclumpend);
1389 print("corrupt clump data - %#llux+%#llux (%,llud bytes)\n",
1390 lastclumpend, v, v);
1391 }
1392 addcicorrupt(v);
1393 totalcorrupt += v;
1394 nb1 = (minclumps+ncib-1)/ncib;
1395 minclumps += (v+ClumpSize+VtMaxLumpSize-1)/(ClumpSize+VtMaxLumpSize);
1396 nb2 = (minclumps+ncib-1)/ncib;
1397 eoffset -= (nb2-nb1)*arena->blocksize;
1398 }
1399
1400 if(haveclump(cl.info.score))
1401 print("warning: duplicate clump %d %V at %#llux+%#d\n", cl.info.type, cl.info.score, offset, n);
1402
1403 /*
1404 * If clumps use different magic numbers, we don't care.
1405 * We'll just use the first one we find and make the others
1406 * follow suit.
1407 */
1408 if(arena->clumpmagic == 0){
1409 print("clump type %d size %d score %V magic %x\n",
1410 cl.info.type, cl.info.size, cl.info.score, magic);
1411 arena->clumpmagic = magic;
1412 if(magic == _ClumpMagic)
1413 arena->version = ArenaVersion4;
1414 else
1415 arena->version = ArenaVersion5;
1416 }
1417 if(magic != arena->clumpmagic)
1418 p32(p, arena->clumpmagic);
1419 if(clumps == 0)
1420 arena->ctime = cl.time;
1421
1422 /*
1423 * Record the clump, update arena stats,
1424 * grow clump info blocks if needed.
1425 */
1426 if(verbose > 1)
1427 print("\tclump %d: %d %V at %#llux+%#ux (%d)\n",
1428 clumps, cl.info.type, cl.info.score, offset, n, n);
1429 addcibuf(&cl.info, 0);
1430 if(minclumps%ncib == 0)
1431 eoffset -= arena->blocksize;
1432 minclumps++;
1433 clumps++;
1434 if(cl.encoding != ClumpENone)
1435 arena->diskstats.cclumps++;
1436 arena->diskstats.uncsize += cl.info.uncsize;
1437 arena->wtime = cl.time;
1438
1439 /*
1440 * Move to next clump.
1441 */
1442 offset += n;
1443 p += n;
1444 lastclumpend = offset;
1445 }else{
1446 /*
1447 * Overwrite malformed clump data with zeros later.
1448 * For now, just record whether it needs to be overwritten.
1449 * Bad regions must be of size at least ClumpSize.
1450 * Postponing the overwriting keeps us from writing past
1451 * the end of the arena data (which might be directory data)
1452 * with zeros.
1453 */
1454 if(!inbad){
1455 inbad = 1;
1456 needtozero = 0;
1457 if(memcmp(p, zero, ClumpSize) != 0)
1458 needtozero = 1;
1459 p += ClumpSize;
1460 offset += ClumpSize;
1461 nbad++;
1462 }else{
1463 if(*p != 0)
1464 needtozero = 1;
1465 p++;
1466 offset++;
1467 }
1468 }
1469 }
1470 pageout();
1471
1472 if(verbose)
1473 print("readable clumps: %d; min. directory entries: %d\n",
1474 clumps, minclumps);
1475 arena->diskstats.used = lastclumpend - boffset;
1476 leaked = eoffset - lastclumpend;
1477 if(verbose)
1478 print("used from %#llux to %#llux = %,lld (%,lld unused)\n",
1479 boffset, lastclumpend, arena->diskstats.used, leaked);
1480
1481 /*
1482 * Finish the SHA1 of the old data.
1483 */
1484 if(arena->diskstats.sealed){
1485 sbdiskhash(&oldsha, toffset);
1486 readdisk(dbuf, toffset, arena->blocksize);
1487 scorecp(dbuf+arena->blocksize-VtScoreSize, zero);
1488 sbupdate(&oldsha, dbuf, toffset, arena->blocksize);
1489 sbscore(&oldsha, oldscore);
1490 }
1491
1492 /*
1493 * If we still don't know the clump magic, the arena
1494 * must be empty. It still needs a value, so make
1495 * something up.
1496 */
1497 if(arena->version == 0)
1498 arena->version = ArenaVersion5;
1499 if(arena->clumpmagic == 0){
1500 if(arena->version == ArenaVersion4)
1501 arena->clumpmagic = _ClumpMagic;
1502 else{
1503 do
1504 arena->clumpmagic = fastrand();
1505 while(arena->clumpmagic==_ClumpMagic
1506 ||arena->clumpmagic==0);
1507 }
1508 head->clumpmagic = arena->clumpmagic;
1509 }
1510
1511 /*
1512 * Guess at number of clumpinfo blocks to load.
1513 * If we guess high, it's no big deal. If we guess low,
1514 * we'll be forced into rewriting the whole directory.
1515 * Still not such a big deal.
1516 */
1517 if(clumps == 0 || arena->diskstats.used == totalcorrupt)
1518 goto Nocib;
1519 if(clumps < arena->diskstats.clumps)
1520 clumps = arena->diskstats.clumps;
1521 if(clumps < ncibuf)
1522 clumps = ncibuf;
1523 clumps += totalcorrupt/
1524 ((arena->diskstats.used - totalcorrupt)/clumps);
1525 clumps += totalcorrupt/2000;
1526 if(clumps < minclumps)
1527 clumps = minclumps;
1528 clumps += ncib-1;
1529 clumps -= clumps%ncib;
1530
1531 /*
1532 * Can't write into the actual data.
1533 */
1534 v = offset0 + arena->size - arena->blocksize;
1535 v -= (clumps+ncib-1)/ncib * arena->blocksize;
1536 if(v < lastclumpend){
1537 v = offset0 + arena->size - arena->blocksize;
1538 clumps = (v-lastclumpend)/arena->blocksize * ncib;
1539 }
1540
1541 if(clumps < minclumps)
1542 print("cannot happen?\n");
1543
1544 /*
1545 * Check clumpinfo blocks against directory we created.
1546 * The tricky part is handling the corrupt sections of arena.
1547 * If possible, we remark just the affected directory entries
1548 * rather than slide everything down.
1549 *
1550 * Allocate clumps+1 blocks and check that we don't need
1551 * the last one at the end.
1552 */
1553 bci = loadci(offset0, arena, clumps+1);
1554 eci = bci+clumps+1;
1555 bcit = cibuf;
1556 ecit = cibuf+ncibuf;
1557
1558 smart = 0; /* Somehow the smart code doesn't do corrupt clumps right. */
1559 Again:
1560 nbad = 0;
1561 ci = bci;
1562 for(cit=bcit; cit<ecit && ci<eci; cit++){
1563 if(cit->corrupt){
1564 vlong n, m;
1565 if(smart){
1566 /*
1567 * If we can, just mark existing entries as corrupt.
1568 */
1569 n = cit->corrupt;
1570 for(xci=ci; n>0 && xci<eci; xci++)
1571 n -= ClumpSize+xci->size;
1572 if(n > 0 || xci >= eci)
1573 goto Dumb;
1574 printed = 0;
1575 for(; ci<xci; ci++){
1576 if(verbose && ci->type != VtCorruptType){
1577 if(!printed){
1578 print("marking directory %d-%d as corrupt\n",
1579 (int)(ci-bci), (int)(xci-bci));
1580 printed = 1;
1581 }
1582 print("\ttype=%d size=%d uncsize=%d score=%V\n",
1583 ci->type, ci->size, ci->uncsize, ci->score);
1584 }
1585 ci->type = VtCorruptType;
1586 }
1587 }else{
1588 Dumb:
1589 print("\trewriting clump directory\n");
1590 /*
1591 * Otherwise, blaze a new trail.
1592 */
1593 n = cit->corrupt;
1594 while(n > 0 && ci < eci){
1595 if(n < ClumpSize)
1596 sysfatal("bad math in clump corrupt");
1597 if(n <= VtMaxLumpSize+ClumpSize)
1598 m = n;
1599 else{
1600 m = VtMaxLumpSize+ClumpSize;
1601 if(n-m < ClumpSize)
1602 m -= ClumpSize;
1603 }
1604 ci->type = VtCorruptType;
1605 ci->size = m-ClumpSize;
1606 ci->uncsize = m-ClumpSize;
1607 memset(ci->score, 0, VtScoreSize);
1608 ci++;
1609 n -= m;
1610 }
1611 }
1612 continue;
1613 }
1614 if(clumpinfocmp(&cit->ci, ci) != 0){
1615 if(verbose && (smart || verbose>1)){
1616 print("clumpinfo %d\n", (int)(ci-bci));
1617 print("\twant: %d %d %d %V\n",
1618 cit->ci.type, cit->ci.size,
1619 cit->ci.uncsize, cit->ci.score);
1620 print("\thave: %d %d %d %V\n",
1621 ci->type, ci->size,
1622 ci->uncsize, ci->score);
1623 }
1624 *ci = cit->ci;
1625 nbad++;
1626 }
1627 ci++;
1628 }
1629 if(ci >= eci || cit < ecit){
1630 print("ran out of space editing existing directory; rewriting\n");
1631 print("# eci %ld ci %ld ecit %ld cit %ld\n", eci-bci, ci-bci, ecit-bcit, cit-bcit);
1632 assert(smart); /* can't happen second time thru */
1633 smart = 0;
1634 goto Again;
1635 }
1636
1637 assert(ci <= eci);
1638 arena->diskstats.clumps = ci-bci;
1639 eoffset = writeci(offset0, arena, bci, ci-bci);
1640 if(sealing && fix)
1641 sbrollback(&newsha, v);
1642 print("eoffset=%lld lastclumpend=%lld diff=%lld unseal=%d\n", eoffset, lastclumpend, eoffset-lastclumpend, unseal);
1643 if(lastclumpend > eoffset)
1644 print("arena directory overwrote blocks! cannot happen!\n");
1645 free(bci);
1646 if(smart && nbad)
1647 print("arena directory has %d bad or missing entries\n", nbad);
1648 Nocib:
1649 if(eoffset - lastclumpend > 64*1024 && (!arena->diskstats.sealed || unseal)){
1650 if(arena->diskstats.sealed)
1651 print("unsealing arena\n");
1652 sealing = 0;
1653 memset(oldscore, 0, VtScoreSize);
1654 }
1655
1656 /*
1657 * Finish the SHA1 of the new data - only meaningful
1658 * if we've been writing to disk (`fix').
1659 */
1660 arena->diskstats.sealed = sealing;
1661 arena->memstats = arena->diskstats;
1662 if(sealing && fix){
1663 uchar tbuf[MaxDiskBlock];
1664
1665 sbdiskhash(&newsha, toffset);
1666 memset(tbuf, 0, sizeof tbuf);
1667 packarena(arena, tbuf);
1668 sbupdate(&newsha, tbuf, toffset, arena->blocksize);
1669 sbscore(&newsha, score);
1670 }
1671 }
1672
1673 void
1674 dumparena(vlong offset, int anum, Arena *arena)
1675 {
1676 char buf[1000];
1677 vlong o, e;
1678 int fd, n;
1679
1680 snprint(buf, sizeof buf, "%s.%d", dumpbase, anum);
1681 if((fd = create(buf, OWRITE, 0666)) < 0){
1682 fprint(2, "create %s: %r\n", buf);
1683 return;
1684 }
1685 e = offset+arena->size;
1686 for(o=offset; o<e; o+=n){
1687 n = 4*M;
1688 if(o+n > e)
1689 n = e-o;
1690 if(pwrite(fd, pagein(o, n), n, o-offset) != n){
1691 fprint(2, "write %s at %#llux: %r\n", buf, o-offset);
1692 return;
1693 }
1694 }
1695 }
1696
1697 void
1698 checkarena(vlong offset, int anum)
1699 {
1700 uchar dbuf[MaxDiskBlock];
1701 uchar *p, oldscore[VtScoreSize], score[VtScoreSize];
1702 Arena arena, oarena;
1703 ArenaHead head;
1704 Info *fmt, *fmta;
1705 int sz;
1706
1707 print("# arena %d: offset %#llux\n", anum, offset);
1708
1709 if(offset >= partend){
1710 print("arena offset out of bounds\n");
1711 return;
1712 }
1713
1714 guessarena(offset, anum, &head, &arena, oldscore, score);
1715
1716 if(verbose){
1717 print("#\tversion=%d name=%s blocksize=%d size=%z",
1718 head.version, head.name, head.blocksize, head.size);
1719 if(head.clumpmagic)
1720 print(" clumpmagic=%#.8ux", head.clumpmagic);
1721 print("\n#\tclumps=%d cclumps=%d used=%,lld uncsize=%,lld\n",
1722 arena.diskstats.clumps, arena.diskstats.cclumps,
1723 arena.diskstats.used, arena.diskstats.uncsize);
1724 print("#\tctime=%t\n", arena.ctime);
1725 print("#\twtime=%t\n", arena.wtime);
1726 if(arena.diskstats.sealed)
1727 print("#\tsealed score=%V\n", score);
1728 }
1729
1730 if(dumpbase){
1731 dumparena(offset, anum, &arena);
1732 return;
1733 }
1734
1735 memset(dbuf, 0, sizeof dbuf);
1736 packarenahead(&head, dbuf);
1737 p = pagein(offset, arena.blocksize);
1738 if(memcmp(dbuf, p, arena.blocksize) != 0){
1739 print("on-disk arena header incorrect\n");
1740 showdiffs(dbuf, p, arena.blocksize,
1741 arena.version==ArenaVersion4 ? headinfo4 : headinfo5);
1742 }
1743 memmove(p, dbuf, arena.blocksize);
1744
1745 memset(dbuf, 0, sizeof dbuf);
1746 packarena(&arena, dbuf);
1747 if(arena.diskstats.sealed)
1748 scorecp(dbuf+arena.blocksize-VtScoreSize, score);
1749 p = pagein(offset+arena.size-arena.blocksize, arena.blocksize);
1750 memset(&oarena, 0, sizeof oarena);
1751 unpackarena(&oarena, p);
1752 if(arena.version == ArenaVersion4){
1753 sz = ArenaSize4;
1754 fmt = tailinfo4;
1755 fmta = tailinfo4a;
1756 }else{
1757 sz = ArenaSize5;
1758 fmt = tailinfo5;
1759 fmta = tailinfo5a;
1760 }
1761 if(p[sz] == 1){
1762 fmt = fmta;
1763 if(oarena.diskstats.sealed){
1764 /*
1765 * some arenas were sealed with the extension
1766 * before we adopted the convention that if it didn't
1767 * add new information it gets dropped.
1768 */
1769 _packarena(&arena, dbuf, 1);
1770 }
1771 }
1772 if(memcmp(dbuf, p, arena.blocksize-VtScoreSize) != 0){
1773 print("on-disk arena tail incorrect\n");
1774 showdiffs(dbuf, p, arena.blocksize-VtScoreSize, fmt);
1775 }
1776 if(arena.diskstats.sealed){
1777 if(oarena.diskstats.sealed)
1778 if(scorecmp(p+arena.blocksize-VtScoreSize, oldscore) != 0){
1779 print("on-disk arena seal score incorrect\n");
1780 print("\tcorrect=%V\n", oldscore);
1781 print("\t disk=%V\n", p+arena.blocksize-VtScoreSize);
1782 }
1783 if(fix && scorecmp(p+arena.blocksize-VtScoreSize, score) != 0){
1784 print("%ssealing arena%s: %V\n",
1785 oarena.diskstats.sealed ? "re" : "",
1786 scorecmp(oldscore, score) == 0 ?
1787 "" : " after changes", score);
1788 }
1789 }
1790 memmove(p, dbuf, arena.blocksize);
1791
1792 pageout();
1793 }
1794
1795 AMapN*
1796 buildamap(void)
1797 {
1798 uchar *p;
1799 vlong o;
1800 ArenaHead h;
1801 AMapN *an;
1802 AMap *m;
1803
1804 an = vtmallocz(sizeof *an);
1805 for(o=ap.arenabase; o<partend; o+=arenasize){
1806 p = pagein(o, Block);
1807 if(unpackarenahead(&h, p) >= 0){
1808 an->map = vtrealloc(an->map, (an->n+1)*sizeof an->map[0]);
1809 m = &an->map[an->n++];
1810 m->start = o;
1811 m->stop = o+h.size;
1812 strcpy(m->name, h.name);
1813 }
1814 }
1815 return an;
1816 }
1817
1818 void
1819 checkmap(void)
1820 {
1821 char *s;
1822 uchar *p;
1823 int i, len;
1824 AMapN *an;
1825 Fmt fmt;
1826
1827 an = buildamap();
1828 fmtstrinit(&fmt);
1829 fmtprint(&fmt, "%ud\n", an->n);
1830 for(i=0; i<an->n; i++)
1831 fmtprint(&fmt, "%s\t%lld\t%lld\n",
1832 an->map[i].name, an->map[i].start, an->map[i].stop);
1833 s = fmtstrflush(&fmt);
1834 len = strlen(s);
1835 if(len > ap.tabsize){
1836 print("arena partition map too long: need %z bytes have %z\n",
1837 (vlong)len, (vlong)ap.tabsize);
1838 len = ap.tabsize;
1839 }
1840
1841 if(ap.tabsize >= 4*M){ /* can't happen - max arenas is 2000 */
1842 print("arena partition map *way* too long\n");
1843 return;
1844 }
1845
1846 p = pagein(ap.tabbase, ap.tabsize);
1847 if(memcmp(p, s, len) != 0){
1848 print("arena partition map incorrect; rewriting.\n");
1849 memmove(p, s, len);
1850 }
1851 pageout();
1852 }
1853
1854 int mainstacksize = 512*1024;
1855
1856 void
1857 threadmain(int argc, char **argv)
1858 {
1859 int mode;
1860
1861 mode = OREAD;
1862 readonly = 1;
1863 ARGBEGIN{
1864 case 'U':
1865 unseal = 1;
1866 break;
1867 case 'a':
1868 arenasize = unittoull(EARGF(usage()));
1869 break;
1870 case 'b':
1871 ap.blocksize = unittoull(EARGF(usage()));
1872 break;
1873 case 'f':
1874 fix = 1;
1875 mode = ORDWR;
1876 readonly = 0;
1877 break;
1878 case 'n':
1879 basename = EARGF(usage());
1880 break;
1881 case 'v':
1882 verbose++;
1883 break;
1884 case 'x':
1885 dumpbase = EARGF(usage());
1886 break;
1887 default:
1888 usage();
1889 }ARGEND
1890
1891 if(argc != 1 && argc != 2)
1892 usage();
1893
1894 file = argv[0];
1895
1896 ventifmtinstall();
1897 fmtinstall('z', zfmt);
1898 fmtinstall('t', tfmt);
1899 quotefmtinstall();
1900
1901 part = initpart(file, mode|ODIRECT);
1902 if(part == nil)
1903 sysfatal("can't open %s: %r", file);
1904 partend = part->size;
1905
1906 if(isonearena()){
1907 checkarena(0, -1);
1908 threadexitsall(nil);
1909 }
1910 checkarenas(argc > 1 ? argv[1] : nil);
1911 checkmap();
1912 threadexitsall(nil);
1913 }