1 |
/* Copyright (c) 1997 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 512 /* maximum beams to free at a time */ |
20 |
#endif |
21 |
#ifndef PCTFREE |
22 |
#define PCTFREE 20 /* maximum fraction to free (%) */ |
23 |
#endif |
24 |
#ifndef MAXFRAG |
25 |
#define MAXFRAG 32767 /* maximum fragments/file to track (0==inf) */ |
26 |
#endif |
27 |
|
28 |
#ifndef BSD |
29 |
#define write writebuf /* safe i/o routines */ |
30 |
#define read readbuf |
31 |
#endif |
32 |
|
33 |
#define FRAGBLK 256 /* number of fragments to allocate at a time */ |
34 |
|
35 |
unsigned hdcachesize = CACHESIZE*1024*1024; /* target cache size */ |
36 |
unsigned long hdclock; /* clock value */ |
37 |
|
38 |
HOLO *hdlist[HDMAX+1]; /* holodeck pointers (NULL term.) */ |
39 |
|
40 |
static struct fraglist { |
41 |
short nlinks; /* number of holodeck sections using us */ |
42 |
short writerr; /* write error encountered */ |
43 |
int nfrags; /* number of known fragments */ |
44 |
BEAMI *fi; /* fragments, descending file position */ |
45 |
long flen; /* last known file length */ |
46 |
} *hdfragl; /* fragment lists, indexed by file descriptor */ |
47 |
|
48 |
static int nhdfragls; /* size of hdfragl array */ |
49 |
|
50 |
|
51 |
hdattach(fd) /* start tracking file fragments for some section */ |
52 |
register int fd; |
53 |
{ |
54 |
if (fd >= nhdfragls) { |
55 |
if (nhdfragls) |
56 |
hdfragl = (struct fraglist *)realloc((char *)hdfragl, |
57 |
(fd+1)*sizeof(struct fraglist)); |
58 |
else |
59 |
hdfragl = (struct fraglist *)malloc( |
60 |
(fd+1)*sizeof(struct fraglist)); |
61 |
if (hdfragl == NULL) |
62 |
error(SYSTEM, "out of memory in hdattach"); |
63 |
bzero((char *)(hdfragl+nhdfragls), |
64 |
(fd+1-nhdfragls)*sizeof(struct fraglist)); |
65 |
nhdfragls = fd+1; |
66 |
} |
67 |
hdfragl[fd].nlinks++; |
68 |
hdfragl[fd].flen = lseek(fd, 0L, 2); /* get file length */ |
69 |
} |
70 |
|
71 |
|
72 |
/* Do we need a routine to locate file fragments given known occupants? */ |
73 |
|
74 |
|
75 |
hdrelease(fd) /* stop tracking file fragments for some section */ |
76 |
register int fd; |
77 |
{ |
78 |
if (fd < 0 | fd >= nhdfragls || !hdfragl[fd].nlinks) |
79 |
return; |
80 |
if (!--hdfragl[fd].nlinks && hdfragl[fd].nfrags) { |
81 |
free((char *)hdfragl[fd].fi); |
82 |
hdfragl[fd].fi = NULL; |
83 |
hdfragl[fd].nfrags = 0; |
84 |
} |
85 |
} |
86 |
|
87 |
|
88 |
markdirty(hp) /* mark holodeck section directory dirty */ |
89 |
register HOLO *hp; |
90 |
{ |
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static BEAMI smudge = {0, -1}; |
92 |
|
93 |
if (hp->dirty) /* already marked? */ |
94 |
return; |
95 |
hp->dirty = 1; |
96 |
if (lseek(hp->fd, biglob(hp)->fo+(nbeams(hp)-1)*sizeof(BEAMI), 0) < 0 |
97 |
|| write(hp->fd, (char *)&smudge, |
98 |
sizeof(BEAMI)) != sizeof(BEAMI)) |
99 |
error(SYSTEM, "seek/write error in markdirty"); |
100 |
} |
101 |
|
102 |
|
103 |
HOLO * |
104 |
hdinit(fd, hproto) /* initialize a holodeck section in a file */ |
105 |
int fd; /* corresponding file descriptor */ |
106 |
HDGRID *hproto; /* holodeck section grid */ |
107 |
{ |
108 |
long fpos; |
109 |
register HOLO *hp; |
110 |
register int n; |
111 |
/* prepare for system errors */ |
112 |
errno = 0; |
113 |
if ((fpos = lseek(fd, 0L, 1)) < 0) |
114 |
error(SYSTEM, "cannot determine holodeck file position"); |
115 |
if (hproto == NULL) { /* assume we're loading it */ |
116 |
HDGRID hpr; |
117 |
/* load header */ |
118 |
if (read(fd, (char *)&hpr, sizeof(HDGRID)) != sizeof(HDGRID)) |
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error(SYSTEM, "cannot load holodeck header"); |
120 |
/* allocate grid */ |
121 |
if ((hp = hdalloc(&hpr)) == NULL) |
122 |
goto memerr; |
123 |
/* load beam directory */ |
124 |
n = nbeams(hp)*sizeof(BEAMI); |
125 |
if (read(fd, (char *)(hp->bi+1), n) != n) |
126 |
error(SYSTEM, "failure loading holodeck directory"); |
127 |
/* check that it's clean */ |
128 |
if (hp->bi[nbeams(hp)].fo < 0) |
129 |
error(USER, "dirty holodeck section"); |
130 |
} else { /* assume we're creating it */ |
131 |
if ((hp = hdalloc(hproto)) == NULL) |
132 |
goto memerr; |
133 |
/* write header and skeleton */ |
134 |
n = nbeams(hp)*sizeof(BEAMI); |
135 |
if (write(fd, (char *)hproto, sizeof(HDGRID)) != |
136 |
sizeof(HDGRID) || |
137 |
write(fd, (char *)(hp->bi+1), n) != n) |
138 |
error(SYSTEM, "cannot write header to holodeck file"); |
139 |
} |
140 |
hp->fd = fd; |
141 |
hp->dirty = 0; |
142 |
biglob(hp)->fo = fpos + sizeof(HDGRID); |
143 |
/* start tracking fragments */ |
144 |
hdattach(fd); |
145 |
/* check rays on disk */ |
146 |
fpos = hdfilen(fd); |
147 |
biglob(hp)->nrd = 0; |
148 |
for (n = hproto == NULL ? nbeams(hp) : 0; n > 0; n--) |
149 |
if (hp->bi[n].nrd) |
150 |
if (hp->bi[n].fo + hp->bi[n].nrd > fpos) |
151 |
hp->bi[n].nrd = 0; /* off end */ |
152 |
else |
153 |
biglob(hp)->nrd += hp->bi[n].nrd; |
154 |
/* add to holodeck list */ |
155 |
for (n = 0; n < HDMAX; n++) |
156 |
if (hdlist[n] == NULL) { |
157 |
hdlist[n] = hp; |
158 |
break; |
159 |
} |
160 |
/* all done */ |
161 |
return(hp); |
162 |
memerr: |
163 |
error(SYSTEM, "cannot allocate holodeck grid"); |
164 |
} |
165 |
|
166 |
|
167 |
int |
168 |
hdsync(hp, all) /* update beams and directory on disk */ |
169 |
register HOLO *hp; |
170 |
int all; |
171 |
{ |
172 |
register int j, n; |
173 |
|
174 |
if (hp == NULL) { /* do all holodecks */ |
175 |
n = 0; |
176 |
for (j = 0; hdlist[j] != NULL; j++) |
177 |
n += hdsync(hdlist[j], all); |
178 |
return(n); |
179 |
} |
180 |
/* sync the beams */ |
181 |
for (j = (all ? nbeams(hp) : 0); j > 0; j--) |
182 |
if (hp->bl[j] != NULL) |
183 |
hdsyncbeam(hp, j); |
184 |
if (!hp->dirty) /* directory clean? */ |
185 |
return(0); |
186 |
errno = 0; |
187 |
if (lseek(hp->fd, biglob(hp)->fo, 0) < 0) |
188 |
error(SYSTEM, "cannot seek on holodeck file"); |
189 |
n = nbeams(hp)*sizeof(BEAMI); |
190 |
if (write(hp->fd, (char *)(hp->bi+1), n) != n) |
191 |
error(SYSTEM, "cannot update holodeck section directory"); |
192 |
hp->dirty = 0; |
193 |
return(1); |
194 |
} |
195 |
|
196 |
|
197 |
unsigned |
198 |
hdmemuse(all) /* return memory usage (in bytes) */ |
199 |
int all; /* include overhead (painful) */ |
200 |
{ |
201 |
long total = 0; |
202 |
register int i, j; |
203 |
|
204 |
for (j = 0; hdlist[j] != NULL; j++) { |
205 |
total += blglob(hdlist[j])->nrm * sizeof(RAYVAL); |
206 |
if (all) { |
207 |
total += sizeof(HOLO) + sizeof(BEAM *) + |
208 |
nbeams(hdlist[j]) * |
209 |
(sizeof(BEAM *)+sizeof(BEAMI)); |
210 |
for (i = nbeams(hdlist[j]); i > 0; i--) |
211 |
if (hdlist[j]->bl[i] != NULL) |
212 |
total += sizeof(BEAM); |
213 |
} |
214 |
} |
215 |
if (all) |
216 |
for (j = 0; j < nhdfragls; j++) { |
217 |
total += sizeof(struct fraglist); |
218 |
if (hdfragl[j].nfrags) |
219 |
total += FRAGBLK*sizeof(BEAMI) * |
220 |
((hdfragl[j].nfrags-1)/FRAGBLK + 1) ; |
221 |
} |
222 |
return(total); |
223 |
} |
224 |
|
225 |
|
226 |
long |
227 |
hdfilen(fd) /* return file length for fd */ |
228 |
int fd; |
229 |
{ |
230 |
long fpos, flen; |
231 |
|
232 |
if (fd < 0) |
233 |
return(-1); |
234 |
if (fd >= nhdfragls || !hdfragl[fd].nlinks) { |
235 |
if ((fpos = lseek(fd, 0L, 1)) < 0) |
236 |
return(-1); |
237 |
flen = lseek(fd, 0L, 2); |
238 |
lseek(fd, fpos, 0); |
239 |
return(flen); |
240 |
} |
241 |
return(hdfragl[fd].flen); |
242 |
} |
243 |
|
244 |
|
245 |
long |
246 |
hdfiluse(fd, all) /* compute file usage (in bytes) */ |
247 |
int fd; /* open file descriptor to check */ |
248 |
int all; /* include overhead and unflushed data */ |
249 |
{ |
250 |
long total = 0; |
251 |
register int i, j; |
252 |
|
253 |
for (j = 0; hdlist[j] != NULL; j++) { |
254 |
if (hdlist[j]->fd != fd) |
255 |
continue; |
256 |
total += biglob(hdlist[j])->nrd * sizeof(RAYVAL); |
257 |
if (all) { |
258 |
for (i = nbeams(hdlist[j]); i > 0; i--) |
259 |
if (hdlist[j]->bl[i] != NULL) |
260 |
total += sizeof(RAYVAL) * |
261 |
(hdlist[j]->bl[i]->nrm - |
262 |
hdlist[j]->bi[i].nrd); |
263 |
total += sizeof(HDGRID) + |
264 |
nbeams(hdlist[j])*sizeof(BEAMI); |
265 |
} |
266 |
} |
267 |
return(total); /* does not include fragments */ |
268 |
} |
269 |
|
270 |
|
271 |
RAYVAL * |
272 |
hdnewrays(hp, i, nr) /* allocate space for add'l rays and return pointer */ |
273 |
register HOLO *hp; |
274 |
register int i; |
275 |
int nr; /* number of new rays desired */ |
276 |
{ |
277 |
RAYVAL *p; |
278 |
int n; |
279 |
|
280 |
if (nr <= 0) |
281 |
return(NULL); |
282 |
if (i < 1 | i > nbeams(hp)) |
283 |
error(CONSISTENCY, "bad beam index given to hdnewrays"); |
284 |
if (hp->bl[i] != NULL) |
285 |
hp->bl[i]->tick = hdclock; /* preempt swap */ |
286 |
if (hdcachesize > 0 && hdmemuse(0) >= hdcachesize) |
287 |
hdfreecache(PCTFREE, NULL); /* free some space */ |
288 |
errno = 0; |
289 |
if (hp->bl[i] == NULL) { /* allocate (and load) */ |
290 |
n = hp->bi[i].nrd + nr; |
291 |
if ((hp->bl[i] = (BEAM *)malloc(hdbsiz(n))) == NULL) |
292 |
goto memerr; |
293 |
blglob(hp)->nrm += n; |
294 |
if (n = hp->bl[i]->nrm = hp->bi[i].nrd) { |
295 |
if (lseek(hp->fd, hp->bi[i].fo, 0) < 0) |
296 |
error(SYSTEM, "seek error on holodeck file"); |
297 |
n *= sizeof(RAYVAL); |
298 |
if (read(hp->fd, (char *)hdbray(hp->bl[i]), n) != n) |
299 |
error(SYSTEM, |
300 |
"error reading beam from holodeck file"); |
301 |
} |
302 |
} else { /* just grow in memory */ |
303 |
hp->bl[i] = (BEAM *)realloc( (char *)hp->bl[i], |
304 |
hdbsiz(hp->bl[i]->nrm + nr) ); |
305 |
if (hp->bl[i] == NULL) |
306 |
goto memerr; |
307 |
blglob(hp)->nrm += nr; |
308 |
} |
309 |
p = hdbray(hp->bl[i]) + hp->bl[i]->nrm; |
310 |
hp->bl[i]->nrm += nr; /* update in-core structure */ |
311 |
bzero((char *)p, nr*sizeof(RAYVAL)); |
312 |
hp->bl[i]->tick = hdclock; /* update LRU clock */ |
313 |
blglob(hp)->tick = hdclock++; |
314 |
return(p); /* point to new rays */ |
315 |
memerr: |
316 |
error(SYSTEM, "out of memory in hdnewrays"); |
317 |
} |
318 |
|
319 |
|
320 |
BEAM * |
321 |
hdgetbeam(hp, i) /* get beam (from file if necessary) */ |
322 |
register HOLO *hp; |
323 |
register int i; |
324 |
{ |
325 |
register int n; |
326 |
|
327 |
if (i < 1 | i > nbeams(hp)) |
328 |
error(CONSISTENCY, "bad beam index given to hdgetbeam"); |
329 |
if (hp->bl[i] == NULL) { /* load from disk */ |
330 |
if (!(n = hp->bi[i].nrd)) |
331 |
return(NULL); |
332 |
if (hdcachesize > 0 && hdmemuse(0) >= hdcachesize) |
333 |
hdfreecache(PCTFREE, NULL); /* get free space */ |
334 |
errno = 0; |
335 |
if ((hp->bl[i] = (BEAM *)malloc(hdbsiz(n))) == NULL) |
336 |
error(SYSTEM, "cannot allocate memory for beam"); |
337 |
blglob(hp)->nrm += hp->bl[i]->nrm = n; |
338 |
if (lseek(hp->fd, hp->bi[i].fo, 0) < 0) |
339 |
error(SYSTEM, "seek error on holodeck file"); |
340 |
n *= sizeof(RAYVAL); |
341 |
if (read(hp->fd, (char *)hdbray(hp->bl[i]), n) != n) |
342 |
error(SYSTEM, "error reading beam from holodeck file"); |
343 |
} |
344 |
hp->bl[i]->tick = hdclock; /* update LRU clock */ |
345 |
blglob(hp)->tick = hdclock++; |
346 |
return(hp->bl[i]); |
347 |
} |
348 |
|
349 |
|
350 |
int |
351 |
hdfilord(hb1, hb2) /* order beams for optimal loading */ |
352 |
register HDBEAMI *hb1, *hb2; |
353 |
{ |
354 |
register int c; |
355 |
/* sort by file descriptor first */ |
356 |
if ((c = hb1->h->fd - hb2->h->fd)) |
357 |
return(c); |
358 |
/* then by position in file */ |
359 |
return(hb1->h->bi[hb1->b].fo - hb2->h->bi[hb2->b].fo); |
360 |
} |
361 |
|
362 |
|
363 |
hdloadbeams(hb, n, bf) /* load a list of beams in optimal order */ |
364 |
register HDBEAMI *hb; /* list gets sorted by hdfilord() */ |
365 |
int n; /* list length */ |
366 |
int (*bf)(); /* callback function (optional) */ |
367 |
{ |
368 |
unsigned origcachesize, memuse; |
369 |
register BEAM *bp; |
370 |
int bytesloaded, needbytes, bytes2free; |
371 |
register int i; |
372 |
/* precheck consistency */ |
373 |
for (i = n; i--; ) |
374 |
if (hb[i].h == NULL || hb[i].b < 1 | hb[i].b > nbeams(hb[i].h)) |
375 |
error(CONSISTENCY, "bad beam in hdloadbeams"); |
376 |
/* sort list for optimal access */ |
377 |
qsort((char *)hb, n, sizeof(HDBEAMI), hdfilord); |
378 |
bytesloaded = needbytes = 0; /* figure out memory needs */ |
379 |
if ((origcachesize = hdcachesize) > 0) { |
380 |
for (i = n; i--; ) |
381 |
if ((bp = hb[i].h->bl[hb[i].b]) != NULL) { |
382 |
bp->tick = hdclock; /* preempt swap */ |
383 |
bytesloaded += bp->nrm; |
384 |
} else /* prepare to load */ |
385 |
needbytes += hb[i].h->bi[hb[i].b].nrd; |
386 |
bytesloaded *= sizeof(RAYVAL); |
387 |
needbytes *= sizeof(RAYVAL); |
388 |
do { /* free enough memory */ |
389 |
memuse = hdmemuse(0); |
390 |
bytes2free = needbytes - (signed)(hdcachesize-memuse); |
391 |
if (bytes2free > (signed)(memuse - bytesloaded)) |
392 |
bytes2free = memuse - bytesloaded; |
393 |
} while (bytes2free > 0 && |
394 |
hdfreecache(100*bytes2free/memuse, NULL) < 0); |
395 |
} |
396 |
hdcachesize = 0; /* load the ordered beams w/o swap */ |
397 |
for (i = 0; i < n; i++) |
398 |
if ((bp = hdgetbeam(hb[i].h, hb[i].b)) != NULL && bf != NULL) |
399 |
(*bf)(bp, hb[i].h, hb[i].b); |
400 |
hdcachesize = origcachesize; /* resume dynamic swapping */ |
401 |
} |
402 |
|
403 |
|
404 |
int |
405 |
hdsyncbeam(hp, i) /* sync beam in memory with beam on disk */ |
406 |
register HOLO *hp; |
407 |
register int i; |
408 |
{ |
409 |
unsigned int nrays; |
410 |
long nfo; |
411 |
unsigned int n; |
412 |
/* check file status */ |
413 |
if (hdfragl[hp->fd].writerr) |
414 |
return(-1); |
415 |
#ifdef DEBUG |
416 |
if (i < 1 | i > nbeams(hp)) |
417 |
error(CONSISTENCY, "bad beam index in hdsyncbeam"); |
418 |
#endif |
419 |
/* is current fragment OK? */ |
420 |
if (hp->bl[i] == NULL || (nrays = hp->bl[i]->nrm) == hp->bi[i].nrd) |
421 |
return(0); |
422 |
/* locate fragment */ |
423 |
if (hp->fd >= nhdfragls || !hdfragl[hp->fd].nlinks) /* untracked */ |
424 |
hp->bi[i].fo = lseek(hp->fd, 0L, 2); |
425 |
|
426 |
else if (hp->bi[i].fo + hp->bi[i].nrd*sizeof(RAYVAL) == |
427 |
hdfragl[hp->fd].flen) /* EOF special case */ |
428 |
hdfragl[hp->fd].flen = (nfo=hp->bi[i].fo) + nrays*sizeof(RAYVAL); |
429 |
|
430 |
else { /* general case */ |
431 |
register struct fraglist *f = &hdfragl[hp->fd]; |
432 |
register int j, k; |
433 |
n = f->nfrags; /* relinquish old fragment */ |
434 |
if (hp->bi[i].nrd) { |
435 |
j = f->nfrags++; |
436 |
#if MAXFRAG |
437 |
if (j >= MAXFRAG-1) |
438 |
f->nfrags--; |
439 |
#endif |
440 |
if (j % FRAGBLK == 0) { /* more frag. space */ |
441 |
if (f->fi == NULL) |
442 |
f->fi = (BEAMI *)malloc( |
443 |
FRAGBLK*sizeof(BEAMI)); |
444 |
else |
445 |
f->fi = (BEAMI *)realloc((char *)f->fi, |
446 |
(j+FRAGBLK)*sizeof(BEAMI)); |
447 |
if (f->fi == NULL) |
448 |
error(SYSTEM, |
449 |
"out of memory in hdsyncbeam"); |
450 |
} |
451 |
for ( ; ; j--) { /* insert in descending list */ |
452 |
if (!j || hp->bi[i].fo < f->fi[j-1].fo) { |
453 |
f->fi[j].fo = hp->bi[i].fo; |
454 |
f->fi[j].nrd = hp->bi[i].nrd; |
455 |
break; |
456 |
} |
457 |
copystruct(f->fi+j, f->fi+(j-1)); |
458 |
} |
459 |
/* coalesce adjacent fragments */ |
460 |
if (j && f->fi[j-1].fo == f->fi[j].fo + |
461 |
f->fi[j].nrd*sizeof(RAYVAL)) { |
462 |
f->fi[j].nrd += f->fi[j-1].nrd; |
463 |
f->fi[j-1].nrd = 0; |
464 |
n = j-1; |
465 |
} |
466 |
if (j+1 < f->nfrags && f->fi[j].fo == f->fi[j+1].fo + |
467 |
f->fi[j+1].nrd*sizeof(RAYVAL)) { |
468 |
f->fi[j+1].nrd += f->fi[j].nrd; |
469 |
f->fi[j].nrd = 0; |
470 |
if (j < n) n = j; |
471 |
} |
472 |
} |
473 |
k = -1; /* find closest-sized fragment */ |
474 |
for (j = (nrays ? f->nfrags : 0); j-- > 0; ) |
475 |
if (f->fi[j].nrd >= nrays && |
476 |
(k < 0 || f->fi[j].nrd < f->fi[k].nrd)) |
477 |
if (f->fi[k=j].nrd == nrays) |
478 |
break; |
479 |
if (k < 0) { /* no fragment -- extend file */ |
480 |
nfo = f->flen; |
481 |
f->flen += nrays*sizeof(RAYVAL); |
482 |
} else { /* else use fragment */ |
483 |
nfo = f->fi[k].fo; |
484 |
f->fi[k].fo += nrays*sizeof(RAYVAL); |
485 |
if (!(f->fi[k].nrd -= nrays) && k < n) |
486 |
n = k; |
487 |
} |
488 |
/* delete empty remnants */ |
489 |
for (j = k = n; k < f->nfrags; j++, k++) { |
490 |
while (f->fi[k].nrd == 0) |
491 |
if (++k >= f->nfrags) |
492 |
goto endloop; |
493 |
if (k > j) |
494 |
copystruct(f->fi+j, f->fi+k); |
495 |
} |
496 |
endloop: |
497 |
f->nfrags = j; |
498 |
} |
499 |
if (nrays) { /* write the new fragment */ |
500 |
errno = 0; |
501 |
if (lseek(hp->fd, nfo, 0) < 0) |
502 |
error(SYSTEM, "cannot seek on holodeck file"); |
503 |
n = hp->bl[i]->nrm * sizeof(RAYVAL); |
504 |
if (write(hp->fd, (char *)hdbray(hp->bl[i]), n) != n) { |
505 |
hdfragl[hp->fd].writerr++; |
506 |
hdsync(hp, 0); /* sync directory */ |
507 |
error(SYSTEM, "write error in hdsyncbeam"); |
508 |
} |
509 |
} |
510 |
biglob(hp)->nrd += nrays - hp->bi[i].nrd; |
511 |
hp->bi[i].nrd = nrays; |
512 |
hp->bi[i].fo = nfo; |
513 |
markdirty(hp); /* section directory now out of date */ |
514 |
return(1); |
515 |
} |
516 |
|
517 |
|
518 |
int |
519 |
hdfreebeam(hp, i) /* free beam, writing if dirty */ |
520 |
register HOLO *hp; |
521 |
register int i; |
522 |
{ |
523 |
int nchanged; |
524 |
|
525 |
if (hp == NULL) { /* clear all holodecks */ |
526 |
nchanged = 0; |
527 |
for (i = 0; hdlist[i] != NULL; i++) |
528 |
nchanged += hdfreebeam(hdlist[i], 0); |
529 |
return(nchanged); |
530 |
} |
531 |
if (hdfragl[hp->fd].writerr) /* check for file error */ |
532 |
return(0); |
533 |
if (i == 0) { /* clear entire holodeck */ |
534 |
nchanged = 0; |
535 |
for (i = nbeams(hp); i > 0; i--) |
536 |
if (hp->bl[i] != NULL) |
537 |
nchanged += hdfreebeam(hp, i); |
538 |
return(nchanged); |
539 |
} |
540 |
#ifdef DEBUG |
541 |
if (i < 1 | i > nbeams(hp)) |
542 |
error(CONSISTENCY, "bad beam index to hdfreebeam"); |
543 |
#endif |
544 |
if (hp->bl[i] == NULL) |
545 |
return(0); |
546 |
/* check for additions */ |
547 |
nchanged = hp->bl[i]->nrm - hp->bi[i].nrd; |
548 |
if (nchanged) |
549 |
hdsyncbeam(hp, i); /* write new fragment */ |
550 |
blglob(hp)->nrm -= hp->bl[i]->nrm; |
551 |
free((char *)hp->bl[i]); /* free memory */ |
552 |
hp->bl[i] = NULL; |
553 |
return(nchanged); |
554 |
} |
555 |
|
556 |
|
557 |
int |
558 |
hdkillbeam(hp, i) /* delete beam from holodeck */ |
559 |
register HOLO *hp; |
560 |
register int i; |
561 |
{ |
562 |
static BEAM emptybeam; |
563 |
int nchanged; |
564 |
|
565 |
if (hp == NULL) { /* clobber all holodecks */ |
566 |
nchanged = 0; |
567 |
for (i = 0; hdlist[i] != NULL; i++) |
568 |
nchanged += hdkillbeam(hdlist[i], 0); |
569 |
return(nchanged); |
570 |
} |
571 |
if (i == 0) { /* clobber entire holodeck */ |
572 |
nchanged = 0; |
573 |
for (i = nbeams(hp); i > 0; i--) |
574 |
if (hp->bi[i].nrd > 0 || hp->bl[i] != NULL) |
575 |
nchanged += hdkillbeam(hp, i); |
576 |
#ifdef DEBUG |
577 |
if (biglob(hp)->nrd != 0 | blglob(hp)->nrm != 0) |
578 |
error(CONSISTENCY, "bad beam count in hdkillbeam"); |
579 |
#endif |
580 |
return(nchanged); |
581 |
} |
582 |
#ifdef DEBUG |
583 |
if (i < 1 | i > nbeams(hp)) |
584 |
error(CONSISTENCY, "bad beam index to hdkillbeam"); |
585 |
#endif |
586 |
if (hp->bl[i] != NULL) { /* free memory */ |
587 |
blglob(hp)->nrm -= nchanged = hp->bl[i]->nrm; |
588 |
free((char *)hp->bl[i]); |
589 |
} else |
590 |
nchanged = hp->bi[i].nrd; |
591 |
if (hp->bi[i].nrd) { /* free file fragment */ |
592 |
hp->bl[i] = &emptybeam; |
593 |
hdsyncbeam(hp, i); |
594 |
} |
595 |
hp->bl[i] = NULL; |
596 |
return(nchanged); |
597 |
} |
598 |
|
599 |
|
600 |
int |
601 |
hdlrulist(hb, nents, n, hp) /* add beams from holodeck to LRU list */ |
602 |
register HDBEAMI *hb; /* beam list */ |
603 |
int nents; /* current list length */ |
604 |
int n; /* maximum list length */ |
605 |
register HOLO *hp; /* section we're adding from */ |
606 |
{ |
607 |
register int i, j; |
608 |
/* insert each beam from hp */ |
609 |
for (i = nbeams(hp); i > 0; i--) { |
610 |
if (hp->bl[i] == NULL) /* check if loaded */ |
611 |
continue; |
612 |
#if 0 |
613 |
if (hp->bl[i]->tick == hdclock) /* preempt swap? */ |
614 |
continue; |
615 |
#endif |
616 |
if ((j = ++nents) >= n) /* grow list if we can */ |
617 |
nents--; |
618 |
for ( ; ; ) { /* bubble into place */ |
619 |
if (!--j || hp->bl[i]->tick >= |
620 |
hb[j-1].h->bl[hb[j-1].b]->tick) { |
621 |
hb[j].h = hp; |
622 |
hb[j].b = i; |
623 |
break; |
624 |
} |
625 |
copystruct(hb+j, hb+(j-1)); |
626 |
} |
627 |
} |
628 |
return(nents); /* return new list length */ |
629 |
} |
630 |
|
631 |
|
632 |
int |
633 |
hdfreecache(pct, honly) /* free up cache space, writing changes */ |
634 |
int pct; /* maximum percentage to free */ |
635 |
register HOLO *honly; /* NULL means check all */ |
636 |
{ |
637 |
HDBEAMI hb[FREEBEAMS]; |
638 |
int freetarget; |
639 |
int n; |
640 |
register int i; |
641 |
/* compute free target */ |
642 |
freetarget = (honly != NULL) ? blglob(honly)->nrm : |
643 |
hdmemuse(0)/sizeof(RAYVAL) ; |
644 |
freetarget = freetarget*pct/100; |
645 |
if (freetarget <= 0) |
646 |
return(0); |
647 |
/* find least recently used */ |
648 |
n = 0; |
649 |
if (honly != NULL) |
650 |
n = hdlrulist(hb, n, FREEBEAMS, honly); |
651 |
else |
652 |
for (i = 0; hdlist[i] != NULL; i++) |
653 |
n = hdlrulist(hb, n, FREEBEAMS, hdlist[i]); |
654 |
/* free LRU beams */ |
655 |
for (i = 0; i < n; i++) { |
656 |
hdfreebeam(hb[i].h, hb[i].b); |
657 |
if ((freetarget -= hb[i].h->bi[hb[i].b].nrd) <= 0) |
658 |
break; |
659 |
} |
660 |
hdsync(honly, 0); /* synchronize directories as necessary */ |
661 |
return(-freetarget); /* return how far past goal we went */ |
662 |
} |
663 |
|
664 |
|
665 |
hddone(hp) /* clean up holodeck section and free */ |
666 |
register HOLO *hp; /* NULL means clean up all */ |
667 |
{ |
668 |
register int i; |
669 |
|
670 |
if (hp == NULL) { /* NULL means clean up everything */ |
671 |
while (hdlist[0] != NULL) |
672 |
hddone(hdlist[0]); |
673 |
return; |
674 |
} |
675 |
/* flush all data and free memory */ |
676 |
hdflush(hp); |
677 |
/* release fragment resources */ |
678 |
hdrelease(hp->fd); |
679 |
/* remove hp from active list */ |
680 |
for (i = 0; hdlist[i] != NULL; i++) |
681 |
if (hdlist[i] == hp) { |
682 |
while ((hdlist[i] = hdlist[i+1]) != NULL) |
683 |
i++; |
684 |
break; |
685 |
} |
686 |
free((char *)hp->bl); /* free beam list */ |
687 |
free((char *)hp); /* free holodeck struct */ |
688 |
} |