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root/radiance/ray/src/hd/holofile.c
Revision: 3.31
Committed: Wed Dec 30 11:30:04 1998 UTC (25 years, 3 months ago) by gwlarson
Content type: text/plain
Branch: MAIN
Changes since 3.30: +9 -6 lines
Log Message:
made it so we don't toss off large fragment for smaller one
fixed accumulation of empty fragments when maximum list size reached

File Contents

# Content
1 /* Copyright (c) 1998 Silicon Graphics, Inc. */
2
3 #ifndef lint
4 static char SCCSid[] = "$SunId$ SGI";
5 #endif
6
7 /*
8 * Routines for managing holodeck files
9 *
10 * 9/30/97 GWLarson
11 */
12
13 #include "holo.h"
14
15 #ifndef CACHESIZE
16 #define CACHESIZE 16 /* default cache size (Mbytes, 0==inf) */
17 #endif
18 #ifndef FREEBEAMS
19 #define FREEBEAMS 1500 /* maximum beams to free at a time */
20 #endif
21 #ifndef PCTFREE
22 #define PCTFREE 15 /* maximum fraction to free (%) */
23 #endif
24 #ifndef MAXFRAGB
25 #define MAXFRAGB 16 /* fragment blocks/file to track (0==inf) */
26 #endif
27 #ifndef MINDIRSEL
28 /* minimum directory seek length */
29 #define MINDIRSEL (4*BUFSIZ/sizeof(BEAMI))
30 #endif
31
32 #ifndef BSD
33 #define write writebuf /* safe i/o routines */
34 #define read readbuf
35 #endif
36
37 #define FRAGBLK 512 /* number of fragments to allocate at a time */
38
39 unsigned hdcachesize = CACHESIZE*1024*1024; /* target cache size */
40 unsigned long hdclock; /* clock value */
41
42 HOLO *hdlist[HDMAX+1]; /* holodeck pointers (NULL term.) */
43
44 static struct fraglist {
45 short nlinks; /* number of holodeck sections using us */
46 short writerr; /* write error encountered */
47 int nfrags; /* number of known fragments */
48 BEAMI *fi; /* fragments, descending file position */
49 long flen; /* last known file length */
50 } *hdfragl; /* fragment lists, indexed by file descriptor */
51
52 static int nhdfragls; /* size of hdfragl array */
53
54
55 char *
56 hdrealloc(ptr, siz, rout) /* (re)allocate memory, retry then error */
57 char *ptr;
58 unsigned siz;
59 char *rout;
60 {
61 register char *newp;
62 /* call malloc/realloc */
63 if (ptr == NULL) newp = (char *)malloc(siz);
64 else newp = (char *)realloc(ptr, siz);
65 /* check success */
66 if (newp == NULL && rout != NULL) {
67 hdfreecache(25, NULL); /* free some memory */
68 errno = 0; /* retry */
69 newp = hdrealloc(ptr, siz, NULL);
70 if (newp == NULL) { /* give up and report error */
71 sprintf(errmsg, "out of memory in %s", rout);
72 error(SYSTEM, errmsg);
73 }
74 }
75 return(newp);
76 }
77
78
79 hdattach(fd) /* start tracking file fragments for some section */
80 register int fd;
81 {
82 if (fd >= nhdfragls) {
83 hdfragl = (struct fraglist *)hdrealloc((char *)hdfragl,
84 (fd+1)*sizeof(struct fraglist), "hdattach");
85 bzero((char *)(hdfragl+nhdfragls),
86 (fd+1-nhdfragls)*sizeof(struct fraglist));
87 nhdfragls = fd+1;
88 }
89 hdfragl[fd].nlinks++;
90 hdfragl[fd].flen = lseek(fd, 0L, 2); /* get file length */
91 }
92
93
94 /* Do we need a routine to locate file fragments given known occupants? */
95
96
97 hdrelease(fd) /* stop tracking file fragments for some section */
98 register int fd;
99 {
100 if (fd < 0 | fd >= nhdfragls || !hdfragl[fd].nlinks)
101 return;
102 if (!--hdfragl[fd].nlinks && hdfragl[fd].nfrags) {
103 free((char *)hdfragl[fd].fi);
104 hdfragl[fd].fi = NULL;
105 hdfragl[fd].nfrags = 0;
106 }
107 }
108
109
110 HOLO *
111 hdinit(fd, hproto) /* initialize a holodeck section in a file */
112 int fd; /* corresponding file descriptor */
113 HDGRID *hproto; /* holodeck section grid */
114 {
115 long rtrunc;
116 long fpos;
117 register HOLO *hp;
118 register int n;
119 /* prepare for system errors */
120 errno = 0;
121 if ((fpos = lseek(fd, 0L, 1)) < 0)
122 error(SYSTEM, "cannot determine holodeck file position");
123 if (hproto == NULL) { /* assume we're loading it */
124 HDGRID hpr;
125 /* load header */
126 if (read(fd, (char *)&hpr, sizeof(HDGRID)) != sizeof(HDGRID))
127 error(SYSTEM, "cannot load holodeck header");
128 /* allocate grid */
129 if ((hp = hdalloc(&hpr)) == NULL)
130 goto memerr;
131 /* load beam directory */
132 n = nbeams(hp)*sizeof(BEAMI);
133 if (read(fd, (char *)(hp->bi+1), n) != n)
134 error(SYSTEM, "failure loading holodeck directory");
135 /* check that it's clean */
136 for (n = nbeams(hp); n > 0; n--)
137 if (hp->bi[n].fo < 0) {
138 hp->bi[n].fo = 0;
139 error(WARNING, "dirty holodeck section");
140 break;
141 }
142 } else { /* assume we're creating it */
143 if ((hp = hdalloc(hproto)) == NULL)
144 goto memerr;
145 /* write header and skeleton */
146 n = nbeams(hp)*sizeof(BEAMI);
147 if (write(fd, (char *)hproto, sizeof(HDGRID)) !=
148 sizeof(HDGRID) ||
149 write(fd, (char *)(hp->bi+1), n) != n)
150 error(SYSTEM, "cannot write header to holodeck file");
151 }
152 hp->fd = fd;
153 hp->dirty = 0;
154 biglob(hp)->fo = fpos + sizeof(HDGRID);
155 /* start tracking fragments */
156 hdattach(fd);
157 /* check rays on disk */
158 fpos = hdfilen(fd);
159 biglob(hp)->nrd = rtrunc = 0;
160 for (n = hproto == NULL ? nbeams(hp) : 0; n > 0; n--)
161 if (hp->bi[n].nrd)
162 if (hp->bi[n].fo+hp->bi[n].nrd*sizeof(RAYVAL) > fpos) {
163 rtrunc += hp->bi[n].nrd;
164 hp->bi[n].nrd = 0;
165 } else
166 biglob(hp)->nrd += hp->bi[n].nrd;
167 if (rtrunc) {
168 sprintf(errmsg, "truncated section, %ld rays lost (%.1f%%)",
169 rtrunc, 100.*rtrunc/(rtrunc+biglob(hp)->nrd));
170 error(WARNING, errmsg);
171 }
172 /* add to holodeck list */
173 for (n = 0; n < HDMAX; n++)
174 if (hdlist[n] == NULL) {
175 hdlist[n] = hp;
176 break;
177 }
178 /* all done */
179 return(hp);
180 memerr:
181 error(SYSTEM, "cannot allocate holodeck grid");
182 }
183
184
185 markdirty(hp, i) /* mark holodeck directory position dirty */
186 register HOLO *hp;
187 int i;
188 {
189 static BEAMI smudge = {0, -1};
190 int mindist, minpos;
191 register int j;
192
193 if (!hp->dirty++) { /* write smudge first time */
194 if (lseek(hp->fd, biglob(hp)->fo+(i-1)*sizeof(BEAMI), 0) < 0
195 || write(hp->fd, (char *)&smudge,
196 sizeof(BEAMI)) != sizeof(BEAMI))
197 error(SYSTEM, "seek/write error in markdirty");
198 hp->dirseg[0].s = i;
199 hp->dirseg[0].n = 1;
200 return;
201 }
202 /* insert into segment list */
203 for (j = hp->dirty; j--; ) {
204 if (!j || hp->dirseg[j-1].s < i) {
205 hp->dirseg[j].s = i;
206 hp->dirseg[j].n = 1;
207 break;
208 }
209 copystruct(hp->dirseg+j, hp->dirseg+(j-1));
210 }
211 do { /* check neighbors */
212 mindist = nbeams(hp); /* find closest */
213 for (j = hp->dirty; --j; )
214 if (hp->dirseg[j].s -
215 (hp->dirseg[j-1].s + hp->dirseg[j-1].n)
216 < mindist) {
217 minpos = j;
218 mindist = hp->dirseg[j].s -
219 (hp->dirseg[j-1].s + hp->dirseg[j-1].n);
220 }
221 /* good enough? */
222 if (hp->dirty <= MAXDIRSE && mindist > MINDIRSEL)
223 break;
224 j = minpos - 1; /* coalesce neighbors */
225 if (hp->dirseg[j].s + hp->dirseg[j].n <
226 hp->dirseg[minpos].s + hp->dirseg[minpos].n)
227 hp->dirseg[j].n = hp->dirseg[minpos].s +
228 hp->dirseg[minpos].n - hp->dirseg[j].s;
229 hp->dirty--;
230 while (++j < hp->dirty) /* close the gap */
231 copystruct(hp->dirseg+j, hp->dirseg+(j+1));
232 } while (mindist <= MINDIRSEL);
233 }
234
235
236 int
237 hdsync(hp, all) /* update beams and directory on disk */
238 register HOLO *hp;
239 int all;
240 {
241 register int j, n;
242
243 if (hp == NULL) { /* do all holodecks */
244 n = 0;
245 for (j = 0; hdlist[j] != NULL; j++)
246 n += hdsync(hdlist[j], all);
247 return(n);
248 }
249 /* sync the beams */
250 for (j = (all ? nbeams(hp) : 0); j > 0; j--)
251 if (hp->bl[j] != NULL)
252 hdsyncbeam(hp, j);
253 if (!hp->dirty) /* directory clean? */
254 return(0);
255 errno = 0; /* write dirty segments */
256 for (j = 0; j < hp->dirty; j++) {
257 if (lseek(hp->fd, biglob(hp)->fo +
258 (hp->dirseg[j].s-1)*sizeof(BEAMI), 0) < 0)
259 error(SYSTEM, "cannot seek on holodeck file");
260 n = hp->dirseg[j].n * sizeof(BEAMI);
261 if (write(hp->fd, (char *)(hp->bi+hp->dirseg[j].s), n) != n)
262 error(SYSTEM, "cannot update section directory");
263 }
264 hp->dirty = 0; /* all clean */
265 return(1);
266 }
267
268
269 unsigned
270 hdmemuse(all) /* return memory usage (in bytes) */
271 int all; /* include overhead (painful) */
272 {
273 long total = 0;
274 register int i, j;
275
276 for (j = 0; hdlist[j] != NULL; j++) {
277 total += blglob(hdlist[j])->nrm * sizeof(RAYVAL);
278 if (all) {
279 total += sizeof(HOLO) + sizeof(BEAM *) +
280 nbeams(hdlist[j]) *
281 (sizeof(BEAM *)+sizeof(BEAMI));
282 for (i = nbeams(hdlist[j]); i > 0; i--)
283 if (hdlist[j]->bl[i] != NULL)
284 total += sizeof(BEAM);
285 }
286 }
287 if (all)
288 for (j = 0; j < nhdfragls; j++) {
289 total += sizeof(struct fraglist);
290 if (hdfragl[j].nfrags)
291 total += FRAGBLK*sizeof(BEAMI) *
292 ((hdfragl[j].nfrags-1)/FRAGBLK + 1) ;
293 }
294 return(total);
295 }
296
297
298 long
299 hdfilen(fd) /* return file length for fd */
300 int fd;
301 {
302 long fpos, flen;
303
304 if (fd < 0)
305 return(-1);
306 if (fd >= nhdfragls || !hdfragl[fd].nlinks) {
307 if ((fpos = lseek(fd, 0L, 1)) < 0)
308 return(-1);
309 flen = lseek(fd, 0L, 2);
310 lseek(fd, fpos, 0);
311 return(flen);
312 }
313 return(hdfragl[fd].flen);
314 }
315
316
317 long
318 hdfiluse(fd, all) /* compute file usage (in bytes) */
319 int fd; /* open file descriptor to check */
320 int all; /* include overhead and unflushed data */
321 {
322 long total = 0;
323 register int i, j;
324
325 for (j = 0; hdlist[j] != NULL; j++) {
326 if (hdlist[j]->fd != fd)
327 continue;
328 total += biglob(hdlist[j])->nrd * sizeof(RAYVAL);
329 if (all) {
330 for (i = nbeams(hdlist[j]); i > 0; i--)
331 if (hdlist[j]->bl[i] != NULL)
332 total += sizeof(RAYVAL) *
333 (hdlist[j]->bl[i]->nrm -
334 hdlist[j]->bi[i].nrd);
335 total += sizeof(HDGRID) +
336 nbeams(hdlist[j])*sizeof(BEAMI);
337 }
338 }
339 return(total); /* does not include fragments */
340 }
341
342
343 RAYVAL *
344 hdnewrays(hp, i, nr) /* allocate space for add'l rays and return pointer */
345 register HOLO *hp;
346 register int i;
347 int nr; /* number of new rays desired */
348 {
349 RAYVAL *p;
350 int n;
351
352 if (nr <= 0)
353 return(NULL);
354 if (i < 1 | i > nbeams(hp))
355 error(CONSISTENCY, "bad beam index given to hdnewrays");
356 if (hp->bl[i] != NULL)
357 hp->bl[i]->tick = hdclock; /* preempt swap */
358 if (hdcachesize > 0 && hdmemuse(0) >= hdcachesize)
359 hdfreecache(PCTFREE, NULL); /* free some space */
360 if (hp->bl[i] == NULL) { /* allocate (and load) */
361 n = hp->bi[i].nrd + nr;
362 hp->bl[i] = (BEAM *)hdrealloc(NULL, hdbsiz(n), "hdnewrays");
363 blglob(hp)->nrm += n;
364 if (n = hp->bl[i]->nrm = hp->bi[i].nrd) {
365 errno = 0;
366 if (lseek(hp->fd, hp->bi[i].fo, 0) < 0)
367 error(SYSTEM, "seek error on holodeck file");
368 n *= sizeof(RAYVAL);
369 if (read(hp->fd, (char *)hdbray(hp->bl[i]), n) != n)
370 error(SYSTEM,
371 "error reading beam from holodeck file");
372 }
373 } else { /* just grow in memory */
374 hp->bl[i] = (BEAM *)hdrealloc((char *)hp->bl[i],
375 hdbsiz(hp->bl[i]->nrm + nr), "hdnewrays");
376 blglob(hp)->nrm += nr;
377 }
378 p = hdbray(hp->bl[i]) + hp->bl[i]->nrm;
379 hp->bl[i]->nrm += nr; /* update in-core structure */
380 bzero((char *)p, nr*sizeof(RAYVAL));
381 blglob(hp)->tick = hp->bl[i]->tick = hdclock++; /* update LRU clock */
382 return(p); /* point to new rays */
383 }
384
385
386 BEAM *
387 hdgetbeam(hp, i) /* get beam (from file if necessary) */
388 register HOLO *hp;
389 register int i;
390 {
391 register int n;
392
393 if (i < 1 | i > nbeams(hp))
394 error(CONSISTENCY, "bad beam index given to hdgetbeam");
395 if (hp->bl[i] == NULL) { /* load from disk */
396 if (!(n = hp->bi[i].nrd))
397 return(NULL);
398 if (hdcachesize > 0 && hdmemuse(0) >= hdcachesize)
399 hdfreecache(PCTFREE, NULL); /* get free space */
400 hp->bl[i] = (BEAM *)hdrealloc(NULL, hdbsiz(n), "hdgetbeam");
401 blglob(hp)->nrm += hp->bl[i]->nrm = n;
402 errno = 0;
403 if (lseek(hp->fd, hp->bi[i].fo, 0) < 0)
404 error(SYSTEM, "seek error on holodeck file");
405 n *= sizeof(RAYVAL);
406 if (read(hp->fd, (char *)hdbray(hp->bl[i]), n) != n)
407 error(SYSTEM, "error reading beam from holodeck file");
408 }
409 blglob(hp)->tick = hp->bl[i]->tick = hdclock++; /* update LRU clock */
410 return(hp->bl[i]);
411 }
412
413
414 int
415 hdfilord(hb1, hb2) /* order beams for quick loading */
416 register HDBEAMI *hb1, *hb2;
417 {
418 register long c;
419 /* residents go first */
420 if (hb2->h->bl[hb2->b] != NULL)
421 return(hb1->h->bl[hb1->b] == NULL);
422 if (hb1->h->bl[hb1->b] != NULL)
423 return(-1);
424 /* otherwise sort by file descriptor */
425 if ((c = hb1->h->fd - hb2->h->fd))
426 return(c);
427 /* then by position in file */
428 c = hb1->h->bi[hb1->b].fo - hb2->h->bi[hb2->b].fo;
429 return(c > 0 ? 1 : c < 0 ? -1 : 0);
430 }
431
432
433 hdloadbeams(hb, n, bf) /* load a list of beams in optimal order */
434 register HDBEAMI *hb; /* list gets sorted by hdfilord() */
435 int n; /* list length */
436 int (*bf)(); /* callback function (optional) */
437 {
438 unsigned origcachesize, memuse;
439 int bytesloaded, needbytes, bytes2free;
440 register BEAM *bp;
441 register int i;
442 /* precheck consistency */
443 if (n <= 0) return;
444 for (i = n; i--; )
445 if (hb[i].h == NULL || hb[i].b < 1 | hb[i].b > nbeams(hb[i].h))
446 error(CONSISTENCY, "bad beam in hdloadbeams");
447 /* sort list for optimal access */
448 qsort((char *)hb, n, sizeof(HDBEAMI), hdfilord);
449 bytesloaded = 0; /* run through loaded beams */
450 for ( ; n && (bp = hb->h->bl[hb->b]) != NULL; n--, hb++) {
451 bp->tick = hdclock; /* preempt swap */
452 bytesloaded += bp->nrm;
453 if (bf != NULL)
454 (*bf)(bp, hb);
455 }
456 bytesloaded *= sizeof(RAYVAL);
457 if ((origcachesize = hdcachesize) > 0) {
458 needbytes = 0; /* figure out memory needs */
459 for (i = n; i--; )
460 needbytes += hb[i].h->bi[hb[i].b].nrd;
461 needbytes *= sizeof(RAYVAL);
462 do { /* free enough memory */
463 memuse = hdmemuse(0);
464 bytes2free = needbytes - (int)(hdcachesize-memuse);
465 if (bytes2free > (int)(memuse - bytesloaded))
466 bytes2free = memuse - bytesloaded;
467 } while (bytes2free > 0 &&
468 hdfreecache(100*bytes2free/memuse, NULL) < 0);
469 hdcachesize = 0; /* load beams w/o swap */
470 }
471 for (i = 0; i < n; i++)
472 if ((bp = hdgetbeam(hb[i].h, hb[i].b)) != NULL && bf != NULL)
473 (*bf)(bp, hb+i);
474 hdcachesize = origcachesize; /* resume dynamic swapping */
475 }
476
477
478 hdfreefrag(fd, bi) /* free a file fragment */
479 int fd;
480 register BEAMI *bi;
481 {
482 register struct fraglist *f;
483 register int j, k;
484
485 if (bi->nrd == 0)
486 return;
487 #ifdef DEBUG
488 if (fd < 0 | fd >= nhdfragls || !hdfragl[fd].nlinks)
489 error(CONSISTENCY, "bad file descriptor in hdfreefrag");
490 #endif
491 f = &hdfragl[fd];
492 if (f->nfrags % FRAGBLK == 0) { /* delete empty remnants */
493 for (j = k = 0; k < f->nfrags; j++, k++) {
494 while (f->fi[k].nrd == 0)
495 if (++k >= f->nfrags)
496 goto endloop;
497 if (k > j)
498 copystruct(f->fi+j, f->fi+k);
499 }
500 endloop:
501 f->nfrags = j;
502 }
503 j = f->nfrags++; /* allocate a slot in free list */
504 #if MAXFRAGB
505 if (j >= MAXFRAGB*FRAGBLK) {
506 f->nfrags = j--; /* stop list growth */
507 if (bi->nrd <= f->fi[j].nrd)
508 return; /* new one no better than discard */
509 }
510 #endif
511 if (j % FRAGBLK == 0) { /* more free list space */
512 register BEAMI *newp;
513 if (f->fi == NULL)
514 newp = (BEAMI *)malloc((j+FRAGBLK)*sizeof(BEAMI));
515 else
516 newp = (BEAMI *)realloc((char *)f->fi,
517 (j+FRAGBLK)*sizeof(BEAMI));
518 if (newp == NULL) {
519 f->nfrags--; /* graceful failure */
520 return;
521 }
522 f->fi = newp;
523 }
524 for ( ; ; j--) { /* insert in descending list */
525 if (!j || bi->fo < f->fi[j-1].fo) {
526 f->fi[j].fo = bi->fo;
527 f->fi[j].nrd = bi->nrd;
528 break;
529 }
530 copystruct(f->fi+j, f->fi+(j-1));
531 }
532 /* coalesce adjacent fragments */
533 /* successors never empty */
534 if (j && f->fi[j-1].fo == f->fi[j].fo + f->fi[j].nrd*sizeof(RAYVAL)) {
535 f->fi[j].nrd += f->fi[j-1].nrd;
536 f->fi[j-1].nrd = 0;
537 }
538 for (k = j+1; k < f->nfrags; k++) /* get non-empty predecessor */
539 if (f->fi[k].nrd) {
540 if (f->fi[j].fo == f->fi[k].fo +
541 f->fi[k].nrd*sizeof(RAYVAL)) {
542 f->fi[k].nrd += f->fi[j].nrd;
543 f->fi[j].nrd = 0;
544 }
545 break;
546 }
547 }
548
549
550 long
551 hdallocfrag(fd, nrays) /* allocate a file fragment */
552 int fd;
553 unsigned int4 nrays;
554 {
555 register struct fraglist *f;
556 register int j, k;
557 long nfo;
558
559 if (nrays == 0)
560 return(-1L);
561 #ifdef DEBUG
562 if (fd < 0 | fd >= nhdfragls || !hdfragl[fd].nlinks)
563 error(CONSISTENCY, "bad file descriptor in hdallocfrag");
564 #endif
565 f = &hdfragl[fd];
566 k = -1; /* find closest-sized fragment */
567 for (j = f->nfrags; j-- > 0; )
568 if (f->fi[j].nrd >= nrays &&
569 (k < 0 || f->fi[j].nrd < f->fi[k].nrd))
570 if (f->fi[k=j].nrd == nrays)
571 break;
572 if (k < 0) { /* no fragment -- extend file */
573 nfo = f->flen;
574 f->flen += nrays*sizeof(RAYVAL);
575 } else { /* else use fragment */
576 nfo = f->fi[k].fo;
577 f->fi[k].fo += nrays*sizeof(RAYVAL);
578 f->fi[k].nrd -= nrays;
579 }
580 return(nfo);
581 }
582
583
584 int
585 hdsyncbeam(hp, i) /* sync beam in memory with beam on disk */
586 register HOLO *hp;
587 register int i;
588 {
589 unsigned int4 nrays;
590 unsigned int n;
591 long nfo;
592 /* check file status */
593 if (hdfragl[hp->fd].writerr)
594 return(-1);
595 #ifdef DEBUG
596 if (i < 1 | i > nbeams(hp))
597 error(CONSISTENCY, "bad beam index in hdsyncbeam");
598 #endif
599 /* is current fragment OK? */
600 if (hp->bl[i] == NULL || (nrays = hp->bl[i]->nrm) == hp->bi[i].nrd)
601 return(0);
602 if (hp->bi[i].nrd) /* relinquish old fragment */
603 hdfreefrag(hp->fd, &hp->bi[i]);
604 if (nrays) { /* get and write new fragment */
605 nfo = hdallocfrag(hp->fd, nrays);
606 errno = 0;
607 if (lseek(hp->fd, nfo, 0) < 0)
608 error(SYSTEM, "cannot seek on holodeck file");
609 n = hp->bl[i]->nrm * sizeof(RAYVAL);
610 if (write(hp->fd, (char *)hdbray(hp->bl[i]), n) != n) {
611 hdfragl[hp->fd].writerr++;
612 hdsync(NULL, 0); /* sync directories */
613 error(SYSTEM, "write error in hdsyncbeam");
614 }
615 hp->bi[i].fo = nfo;
616 } else
617 hp->bi[i].fo = 0L;
618 biglob(hp)->nrd += nrays - hp->bi[i].nrd;
619 hp->bi[i].nrd = nrays;
620 markdirty(hp, i); /* section directory now out of date */
621 return(1);
622 }
623
624
625 int
626 hdfreebeam(hp, i) /* free beam, writing if dirty */
627 register HOLO *hp;
628 register int i;
629 {
630 int nchanged;
631
632 if (hp == NULL) { /* clear all holodecks */
633 nchanged = 0;
634 for (i = 0; hdlist[i] != NULL; i++)
635 nchanged += hdfreebeam(hdlist[i], 0);
636 return(nchanged);
637 }
638 if (hdfragl[hp->fd].writerr) /* check for file error */
639 return(0);
640 if (i == 0) { /* clear entire holodeck */
641 nchanged = 0;
642 for (i = nbeams(hp); i > 0; i--)
643 if (hp->bl[i] != NULL)
644 nchanged += hdfreebeam(hp, i);
645 return(nchanged);
646 }
647 #ifdef DEBUG
648 if (i < 1 | i > nbeams(hp))
649 error(CONSISTENCY, "bad beam index to hdfreebeam");
650 #endif
651 if (hp->bl[i] == NULL)
652 return(0);
653 /* check for additions */
654 nchanged = hp->bl[i]->nrm - hp->bi[i].nrd;
655 if (nchanged)
656 hdsyncbeam(hp, i); /* write new fragment */
657 blglob(hp)->nrm -= hp->bl[i]->nrm;
658 free((char *)hp->bl[i]); /* free memory */
659 hp->bl[i] = NULL;
660 return(nchanged);
661 }
662
663
664 int
665 hdkillbeam(hp, i) /* delete beam from holodeck */
666 register HOLO *hp;
667 register int i;
668 {
669 static BEAM emptybeam;
670 int nchanged;
671
672 if (hp == NULL) { /* clobber all holodecks */
673 nchanged = 0;
674 for (i = 0; hdlist[i] != NULL; i++)
675 nchanged += hdkillbeam(hdlist[i], 0);
676 return(nchanged);
677 }
678 if (i == 0) { /* clobber entire holodeck */
679 nchanged = 0;
680 for (i = nbeams(hp); i > 0; i--)
681 if (hp->bi[i].nrd > 0 || hp->bl[i] != NULL)
682 nchanged += hdkillbeam(hp, i);
683 #ifdef DEBUG
684 if (biglob(hp)->nrd != 0 | blglob(hp)->nrm != 0)
685 error(CONSISTENCY, "bad beam count in hdkillbeam");
686 #endif
687 return(nchanged);
688 }
689 #ifdef DEBUG
690 if (i < 1 | i > nbeams(hp))
691 error(CONSISTENCY, "bad beam index to hdkillbeam");
692 #endif
693 if (hp->bl[i] != NULL) { /* free memory */
694 blglob(hp)->nrm -= nchanged = hp->bl[i]->nrm;
695 free((char *)hp->bl[i]);
696 } else
697 nchanged = hp->bi[i].nrd;
698 if (hp->bi[i].nrd) { /* free file fragment */
699 hp->bl[i] = &emptybeam;
700 hdsyncbeam(hp, i);
701 }
702 hp->bl[i] = NULL;
703 return(nchanged);
704 }
705
706
707 int
708 hdlrulist(hb, nents, n, hp) /* add beams from holodeck to LRU list */
709 register HDBEAMI *hb; /* beam list */
710 int nents; /* current list length */
711 int n; /* maximum list length */
712 register HOLO *hp; /* section we're adding from */
713 {
714 register int i, j;
715 /* insert each beam from hp */
716 for (i = 1; i <= nbeams(hp); i++) {
717 if (hp->bl[i] == NULL) /* check if loaded */
718 continue;
719 #if 0
720 if (hp->bl[i]->tick == hdclock) /* preempt swap? */
721 continue;
722 #endif
723 if ((j = ++nents) >= n) /* grow list if we can */
724 nents--;
725 for ( ; ; ) { /* bubble into place */
726 if (!--j || hp->bl[i]->tick >=
727 hb[j-1].h->bl[hb[j-1].b]->tick) {
728 hb[j].h = hp;
729 hb[j].b = i;
730 break;
731 }
732 copystruct(hb+j, hb+(j-1));
733 }
734 }
735 return(nents); /* return new list length */
736 }
737
738
739 int
740 hdfreecache(pct, honly) /* free up cache space, writing changes */
741 int pct; /* maximum percentage to free */
742 register HOLO *honly; /* NULL means check all */
743 {
744 HDBEAMI hb[FREEBEAMS];
745 int freetarget;
746 int n;
747 register int i;
748 #ifdef DEBUG
749 unsigned membefore;
750
751 membefore = hdmemuse(0);
752 #endif
753 /* compute free target */
754 freetarget = (honly != NULL) ? blglob(honly)->nrm :
755 hdmemuse(0)/sizeof(RAYVAL) ;
756 freetarget = freetarget*pct/100;
757 if (freetarget <= 0)
758 return(0);
759 /* find least recently used */
760 n = 0;
761 if (honly != NULL)
762 n = hdlrulist(hb, n, FREEBEAMS, honly);
763 else
764 for (i = 0; hdlist[i] != NULL; i++)
765 n = hdlrulist(hb, n, FREEBEAMS, hdlist[i]);
766 /* free LRU beams */
767 for (i = 0; i < n; i++) {
768 hdfreebeam(hb[i].h, hb[i].b);
769 if ((freetarget -= hb[i].h->bi[hb[i].b].nrd) <= 0)
770 break;
771 }
772 hdsync(honly, 0); /* synchronize directories as necessary */
773 #ifdef DEBUG
774 sprintf(errmsg,
775 "%dK before, %dK after hdfreecache (%dK total), %d rays short\n",
776 membefore>>10, hdmemuse(0)>>10, hdmemuse(1)>>10, freetarget);
777 wputs(errmsg);
778 #endif
779 return(-freetarget); /* return how far past goal we went */
780 }
781
782
783 hddone(hp) /* clean up holodeck section and free */
784 register HOLO *hp; /* NULL means clean up all */
785 {
786 register int i;
787
788 if (hp == NULL) { /* NULL means clean up everything */
789 while (hdlist[0] != NULL)
790 hddone(hdlist[0]);
791 free((char *)hdfragl);
792 hdfragl = NULL; nhdfragls = 0;
793 return;
794 }
795 /* flush all data and free memory */
796 hdfreebeam(hp, 0);
797 hdsync(hp, 0);
798 /* release fragment resources */
799 hdrelease(hp->fd);
800 /* remove hp from active list */
801 for (i = 0; hdlist[i] != NULL; i++)
802 if (hdlist[i] == hp) {
803 while ((hdlist[i] = hdlist[i+1]) != NULL)
804 i++;
805 break;
806 }
807 free((char *)hp->bl); /* free beam list */
808 free((char *)hp); /* free holodeck struct */
809 }