| 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 1024 /* maximum beams to free at a time */ |
| 20 |
#endif |
| 21 |
#ifndef PCTFREE |
| 22 |
#define PCTFREE 15 /* 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 |
{ |
| 91 |
static BEAMI smudge = {0, -1}; |
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|
| 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 */ |
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errno = 0; |
| 113 |
if ((fpos = lseek(fd, 0L, 1)) < 0) |
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error(SYSTEM, "cannot determine holodeck file position"); |
| 115 |
if (hproto == NULL) { /* assume we're loading it */ |
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HDGRID hpr; |
| 117 |
/* load header */ |
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if (read(fd, (char *)&hpr, sizeof(HDGRID)) != sizeof(HDGRID)) |
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error(SYSTEM, "cannot load holodeck header"); |
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/* allocate grid */ |
| 121 |
if ((hp = hdalloc(&hpr)) == NULL) |
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goto memerr; |
| 123 |
/* load beam directory */ |
| 124 |
n = nbeams(hp)*sizeof(BEAMI); |
| 125 |
if (read(fd, (char *)(hp->bi+1), n) != n) |
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error(SYSTEM, "failure loading holodeck directory"); |
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/* check that it's clean */ |
| 128 |
if (hp->bi[nbeams(hp)].fo < 0) |
| 129 |
error(WARNING, "dirty holodeck section"); |
| 130 |
} else { /* assume we're creating it */ |
| 131 |
if ((hp = hdalloc(hproto)) == NULL) |
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goto memerr; |
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/* 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); |
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return(n); |
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} |
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/* 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? */ |
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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 |
|
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if (fd < 0) |
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return(-1); |
| 234 |
if (fd >= nhdfragls || !hdfragl[fd].nlinks) { |
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if ((fpos = lseek(fd, 0L, 1)) < 0) |
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return(-1); |
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flen = lseek(fd, 0L, 2); |
| 238 |
lseek(fd, fpos, 0); |
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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 quick loading */ |
| 352 |
register HDBEAMI *hb1, *hb2; |
| 353 |
{ |
| 354 |
register long c; |
| 355 |
/* residents go first */ |
| 356 |
if (hb2->h->bl[hb2->b] != NULL) |
| 357 |
return(hb1->h->bl[hb1->b] == NULL); |
| 358 |
if (hb1->h->bl[hb1->b] != NULL) |
| 359 |
return(-1); |
| 360 |
/* otherwise sort by file descriptor */ |
| 361 |
if ((c = hb1->h->fd - hb2->h->fd)) |
| 362 |
return(c); |
| 363 |
/* then by position in file */ |
| 364 |
c = hb1->h->bi[hb1->b].fo - hb2->h->bi[hb2->b].fo; |
| 365 |
return(c > 0 ? 1 : c < 0 ? -1 : 0); |
| 366 |
} |
| 367 |
|
| 368 |
|
| 369 |
hdloadbeams(hb, n, bf) /* load a list of beams in optimal order */ |
| 370 |
register HDBEAMI *hb; /* list gets sorted by hdfilord() */ |
| 371 |
int n; /* list length */ |
| 372 |
int (*bf)(); /* callback function (optional) */ |
| 373 |
{ |
| 374 |
unsigned origcachesize, memuse; |
| 375 |
register BEAM *bp; |
| 376 |
int bytesloaded, needbytes, bytes2free; |
| 377 |
register int i; |
| 378 |
/* precheck consistency */ |
| 379 |
for (i = n; i--; ) |
| 380 |
if (hb[i].h == NULL || hb[i].b < 1 | hb[i].b > nbeams(hb[i].h)) |
| 381 |
error(CONSISTENCY, "bad beam in hdloadbeams"); |
| 382 |
/* sort list for optimal access */ |
| 383 |
qsort((char *)hb, n, sizeof(HDBEAMI), hdfilord); |
| 384 |
bytesloaded = 0; /* run through loaded beams */ |
| 385 |
for ( ; n && (bp = hb->h->bl[hb->b]) != NULL; n--, hb++) { |
| 386 |
bp->tick = hdclock; /* preempt swap */ |
| 387 |
bytesloaded += bp->nrm; |
| 388 |
if (bf != NULL) |
| 389 |
(*bf)(bp, hb->h, hb->b); |
| 390 |
} |
| 391 |
bytesloaded *= sizeof(RAYVAL); |
| 392 |
if ((origcachesize = hdcachesize) > 0) { |
| 393 |
needbytes = 0; /* figure out memory needs */ |
| 394 |
for (i = n; i--; ) |
| 395 |
needbytes += hb[i].h->bi[hb[i].b].nrd; |
| 396 |
needbytes *= sizeof(RAYVAL); |
| 397 |
do { /* free enough memory */ |
| 398 |
memuse = hdmemuse(0); |
| 399 |
bytes2free = needbytes - (int)(hdcachesize-memuse); |
| 400 |
if (bytes2free > (int)(memuse - bytesloaded)) |
| 401 |
bytes2free = memuse - bytesloaded; |
| 402 |
} while (bytes2free > 0 && |
| 403 |
hdfreecache(100*bytes2free/memuse, NULL) < 0); |
| 404 |
hdcachesize = 0; /* load beams w/o swap */ |
| 405 |
} |
| 406 |
for (i = 0; i < n; i++) |
| 407 |
if ((bp = hdgetbeam(hb[i].h, hb[i].b)) != NULL && bf != NULL) |
| 408 |
(*bf)(bp, hb[i].h, hb[i].b); |
| 409 |
hdcachesize = origcachesize; /* resume dynamic swapping */ |
| 410 |
} |
| 411 |
|
| 412 |
|
| 413 |
hdfreefrag(fd, bi) /* free a file fragment */ |
| 414 |
int fd; |
| 415 |
register BEAMI *bi; |
| 416 |
{ |
| 417 |
register struct fraglist *f; |
| 418 |
register int j, k; |
| 419 |
|
| 420 |
if (bi->nrd == 0) |
| 421 |
return; |
| 422 |
#ifdef DEBUG |
| 423 |
if (fd < 0 | fd >= nhdfragls || !hdfragl[fd].nlinks) |
| 424 |
error(CONSISTENCY, "bad file descriptor in hdfreefrag"); |
| 425 |
#endif |
| 426 |
f = &hdfragl[fd]; |
| 427 |
if (f->nfrags % FRAGBLK == 0) { /* delete empty remnants */ |
| 428 |
for (j = k = 0; k < f->nfrags; j++, k++) { |
| 429 |
while (f->fi[k].nrd == 0) |
| 430 |
if (++k >= f->nfrags) |
| 431 |
goto endloop; |
| 432 |
if (k > j) |
| 433 |
copystruct(f->fi+j, f->fi+k); |
| 434 |
} |
| 435 |
endloop: |
| 436 |
f->nfrags = j; |
| 437 |
} |
| 438 |
j = f->nfrags++; /* allocate a slot in free list */ |
| 439 |
#if MAXFRAG |
| 440 |
if (j >= MAXFRAG-1) |
| 441 |
f->nfrags--; |
| 442 |
#endif |
| 443 |
if (j % FRAGBLK == 0) { /* more free list space */ |
| 444 |
if (f->fi == NULL) |
| 445 |
f->fi = (BEAMI *)malloc(FRAGBLK*sizeof(BEAMI)); |
| 446 |
else |
| 447 |
f->fi = (BEAMI *)realloc((char *)f->fi, |
| 448 |
(j+FRAGBLK)*sizeof(BEAMI)); |
| 449 |
if (f->fi == NULL) |
| 450 |
error(SYSTEM, "out of memory in hdfreefrag"); |
| 451 |
} |
| 452 |
for ( ; ; j--) { /* insert in descending list */ |
| 453 |
if (!j || bi->fo < f->fi[j-1].fo) { |
| 454 |
f->fi[j].fo = bi->fo; |
| 455 |
f->fi[j].nrd = bi->nrd; |
| 456 |
break; |
| 457 |
} |
| 458 |
copystruct(f->fi+j, f->fi+(j-1)); |
| 459 |
} |
| 460 |
/* coalesce adjacent fragments */ |
| 461 |
/* successors never empty */ |
| 462 |
if (j && f->fi[j-1].fo == f->fi[j].fo + f->fi[j].nrd*sizeof(RAYVAL)) { |
| 463 |
f->fi[j].nrd += f->fi[j-1].nrd; |
| 464 |
f->fi[j-1].nrd = 0; |
| 465 |
} |
| 466 |
for (k = j+1; k < f->nfrags; k++) /* get non-empty predecessor */ |
| 467 |
if (f->fi[k].nrd) { |
| 468 |
if (f->fi[j].fo == f->fi[k].fo + |
| 469 |
f->fi[k].nrd*sizeof(RAYVAL)) { |
| 470 |
f->fi[k].nrd += f->fi[j].nrd; |
| 471 |
f->fi[j].nrd = 0; |
| 472 |
} |
| 473 |
break; |
| 474 |
} |
| 475 |
} |
| 476 |
|
| 477 |
|
| 478 |
long |
| 479 |
hdallocfrag(fd, nrays) /* allocate a file fragment */ |
| 480 |
int fd; |
| 481 |
unsigned int4 nrays; |
| 482 |
{ |
| 483 |
register struct fraglist *f; |
| 484 |
register int j, k; |
| 485 |
long nfo; |
| 486 |
|
| 487 |
if (nrays == 0) |
| 488 |
return(-1L); |
| 489 |
#ifdef DEBUG |
| 490 |
if (fd < 0 | fd >= nhdfragls || !hdfragl[fd].nlinks) |
| 491 |
error(CONSISTENCY, "bad file descriptor in hdallocfrag"); |
| 492 |
#endif |
| 493 |
f = &hdfragl[fd]; |
| 494 |
k = -1; /* find closest-sized fragment */ |
| 495 |
for (j = f->nfrags; j-- > 0; ) |
| 496 |
if (f->fi[j].nrd >= nrays && |
| 497 |
(k < 0 || f->fi[j].nrd < f->fi[k].nrd)) |
| 498 |
if (f->fi[k=j].nrd == nrays) |
| 499 |
break; |
| 500 |
if (k < 0) { /* no fragment -- extend file */ |
| 501 |
nfo = f->flen; |
| 502 |
f->flen += nrays*sizeof(RAYVAL); |
| 503 |
} else { /* else use fragment */ |
| 504 |
nfo = f->fi[k].fo; |
| 505 |
f->fi[k].fo += nrays*sizeof(RAYVAL); |
| 506 |
f->fi[k].nrd -= nrays; |
| 507 |
} |
| 508 |
return(nfo); |
| 509 |
} |
| 510 |
|
| 511 |
|
| 512 |
int |
| 513 |
hdsyncbeam(hp, i) /* sync beam in memory with beam on disk */ |
| 514 |
register HOLO *hp; |
| 515 |
register int i; |
| 516 |
{ |
| 517 |
unsigned int4 nrays; |
| 518 |
unsigned int n; |
| 519 |
long nfo; |
| 520 |
/* check file status */ |
| 521 |
if (hdfragl[hp->fd].writerr) |
| 522 |
return(-1); |
| 523 |
#ifdef DEBUG |
| 524 |
if (i < 1 | i > nbeams(hp)) |
| 525 |
error(CONSISTENCY, "bad beam index in hdsyncbeam"); |
| 526 |
#endif |
| 527 |
/* is current fragment OK? */ |
| 528 |
if (hp->bl[i] == NULL || (nrays = hp->bl[i]->nrm) == hp->bi[i].nrd) |
| 529 |
return(0); |
| 530 |
if (hp->bi[i].nrd) /* relinquish old fragment */ |
| 531 |
hdfreefrag(hp->fd, &hp->bi[i]); |
| 532 |
if (nrays) { /* get and write new fragment */ |
| 533 |
nfo = hdallocfrag(hp->fd, nrays); |
| 534 |
errno = 0; |
| 535 |
if (lseek(hp->fd, nfo, 0) < 0) |
| 536 |
error(SYSTEM, "cannot seek on holodeck file"); |
| 537 |
n = hp->bl[i]->nrm * sizeof(RAYVAL); |
| 538 |
if (write(hp->fd, (char *)hdbray(hp->bl[i]), n) != n) { |
| 539 |
hdfragl[hp->fd].writerr++; |
| 540 |
hdsync(NULL, 0); /* sync directories */ |
| 541 |
error(SYSTEM, "write error in hdsyncbeam"); |
| 542 |
} |
| 543 |
hp->bi[i].fo = nfo; |
| 544 |
} else |
| 545 |
hp->bi[i].fo = 0L; |
| 546 |
biglob(hp)->nrd += nrays - hp->bi[i].nrd; |
| 547 |
hp->bi[i].nrd = nrays; |
| 548 |
markdirty(hp); /* section directory now out of date */ |
| 549 |
return(1); |
| 550 |
} |
| 551 |
|
| 552 |
|
| 553 |
int |
| 554 |
hdfreebeam(hp, i) /* free beam, writing if dirty */ |
| 555 |
register HOLO *hp; |
| 556 |
register int i; |
| 557 |
{ |
| 558 |
int nchanged; |
| 559 |
|
| 560 |
if (hp == NULL) { /* clear all holodecks */ |
| 561 |
nchanged = 0; |
| 562 |
for (i = 0; hdlist[i] != NULL; i++) |
| 563 |
nchanged += hdfreebeam(hdlist[i], 0); |
| 564 |
return(nchanged); |
| 565 |
} |
| 566 |
if (hdfragl[hp->fd].writerr) /* check for file error */ |
| 567 |
return(0); |
| 568 |
if (i == 0) { /* clear entire holodeck */ |
| 569 |
nchanged = 0; |
| 570 |
for (i = nbeams(hp); i > 0; i--) |
| 571 |
if (hp->bl[i] != NULL) |
| 572 |
nchanged += hdfreebeam(hp, i); |
| 573 |
return(nchanged); |
| 574 |
} |
| 575 |
#ifdef DEBUG |
| 576 |
if (i < 1 | i > nbeams(hp)) |
| 577 |
error(CONSISTENCY, "bad beam index to hdfreebeam"); |
| 578 |
#endif |
| 579 |
if (hp->bl[i] == NULL) |
| 580 |
return(0); |
| 581 |
/* check for additions */ |
| 582 |
nchanged = hp->bl[i]->nrm - hp->bi[i].nrd; |
| 583 |
if (nchanged) |
| 584 |
hdsyncbeam(hp, i); /* write new fragment */ |
| 585 |
blglob(hp)->nrm -= hp->bl[i]->nrm; |
| 586 |
free((char *)hp->bl[i]); /* free memory */ |
| 587 |
hp->bl[i] = NULL; |
| 588 |
return(nchanged); |
| 589 |
} |
| 590 |
|
| 591 |
|
| 592 |
int |
| 593 |
hdkillbeam(hp, i) /* delete beam from holodeck */ |
| 594 |
register HOLO *hp; |
| 595 |
register int i; |
| 596 |
{ |
| 597 |
static BEAM emptybeam; |
| 598 |
int nchanged; |
| 599 |
|
| 600 |
if (hp == NULL) { /* clobber all holodecks */ |
| 601 |
nchanged = 0; |
| 602 |
for (i = 0; hdlist[i] != NULL; i++) |
| 603 |
nchanged += hdkillbeam(hdlist[i], 0); |
| 604 |
return(nchanged); |
| 605 |
} |
| 606 |
if (i == 0) { /* clobber entire holodeck */ |
| 607 |
nchanged = 0; |
| 608 |
for (i = nbeams(hp); i > 0; i--) |
| 609 |
if (hp->bi[i].nrd > 0 || hp->bl[i] != NULL) |
| 610 |
nchanged += hdkillbeam(hp, i); |
| 611 |
#ifdef DEBUG |
| 612 |
if (biglob(hp)->nrd != 0 | blglob(hp)->nrm != 0) |
| 613 |
error(CONSISTENCY, "bad beam count in hdkillbeam"); |
| 614 |
#endif |
| 615 |
return(nchanged); |
| 616 |
} |
| 617 |
#ifdef DEBUG |
| 618 |
if (i < 1 | i > nbeams(hp)) |
| 619 |
error(CONSISTENCY, "bad beam index to hdkillbeam"); |
| 620 |
#endif |
| 621 |
if (hp->bl[i] != NULL) { /* free memory */ |
| 622 |
blglob(hp)->nrm -= nchanged = hp->bl[i]->nrm; |
| 623 |
free((char *)hp->bl[i]); |
| 624 |
} else |
| 625 |
nchanged = hp->bi[i].nrd; |
| 626 |
if (hp->bi[i].nrd) { /* free file fragment */ |
| 627 |
hp->bl[i] = &emptybeam; |
| 628 |
hdsyncbeam(hp, i); |
| 629 |
} |
| 630 |
hp->bl[i] = NULL; |
| 631 |
return(nchanged); |
| 632 |
} |
| 633 |
|
| 634 |
|
| 635 |
int |
| 636 |
hdlrulist(hb, nents, n, hp) /* add beams from holodeck to LRU list */ |
| 637 |
register HDBEAMI *hb; /* beam list */ |
| 638 |
int nents; /* current list length */ |
| 639 |
int n; /* maximum list length */ |
| 640 |
register HOLO *hp; /* section we're adding from */ |
| 641 |
{ |
| 642 |
register int i, j; |
| 643 |
/* insert each beam from hp */ |
| 644 |
for (i = 1; i <= nbeams(hp); i++) { |
| 645 |
if (hp->bl[i] == NULL) /* check if loaded */ |
| 646 |
continue; |
| 647 |
#if 0 |
| 648 |
if (hp->bl[i]->tick == hdclock) /* preempt swap? */ |
| 649 |
continue; |
| 650 |
#endif |
| 651 |
if ((j = ++nents) >= n) /* grow list if we can */ |
| 652 |
nents--; |
| 653 |
for ( ; ; ) { /* bubble into place */ |
| 654 |
if (!--j || hp->bl[i]->tick >= |
| 655 |
hb[j-1].h->bl[hb[j-1].b]->tick) { |
| 656 |
hb[j].h = hp; |
| 657 |
hb[j].b = i; |
| 658 |
break; |
| 659 |
} |
| 660 |
copystruct(hb+j, hb+(j-1)); |
| 661 |
} |
| 662 |
} |
| 663 |
return(nents); /* return new list length */ |
| 664 |
} |
| 665 |
|
| 666 |
|
| 667 |
int |
| 668 |
hdfreecache(pct, honly) /* free up cache space, writing changes */ |
| 669 |
int pct; /* maximum percentage to free */ |
| 670 |
register HOLO *honly; /* NULL means check all */ |
| 671 |
{ |
| 672 |
HDBEAMI hb[FREEBEAMS]; |
| 673 |
int freetarget; |
| 674 |
int n; |
| 675 |
register int i; |
| 676 |
/* compute free target */ |
| 677 |
freetarget = (honly != NULL) ? blglob(honly)->nrm : |
| 678 |
hdmemuse(0)/sizeof(RAYVAL) ; |
| 679 |
freetarget = freetarget*pct/100; |
| 680 |
if (freetarget <= 0) |
| 681 |
return(0); |
| 682 |
/* find least recently used */ |
| 683 |
n = 0; |
| 684 |
if (honly != NULL) |
| 685 |
n = hdlrulist(hb, n, FREEBEAMS, honly); |
| 686 |
else |
| 687 |
for (i = 0; hdlist[i] != NULL; i++) |
| 688 |
n = hdlrulist(hb, n, FREEBEAMS, hdlist[i]); |
| 689 |
/* free LRU beams */ |
| 690 |
for (i = 0; i < n; i++) { |
| 691 |
hdfreebeam(hb[i].h, hb[i].b); |
| 692 |
if ((freetarget -= hb[i].h->bi[hb[i].b].nrd) <= 0) |
| 693 |
break; |
| 694 |
} |
| 695 |
hdsync(honly, 0); /* synchronize directories as necessary */ |
| 696 |
return(-freetarget); /* return how far past goal we went */ |
| 697 |
} |
| 698 |
|
| 699 |
|
| 700 |
hddone(hp) /* clean up holodeck section and free */ |
| 701 |
register HOLO *hp; /* NULL means clean up all */ |
| 702 |
{ |
| 703 |
register int i; |
| 704 |
|
| 705 |
if (hp == NULL) { /* NULL means clean up everything */ |
| 706 |
while (hdlist[0] != NULL) |
| 707 |
hddone(hdlist[0]); |
| 708 |
return; |
| 709 |
} |
| 710 |
/* flush all data and free memory */ |
| 711 |
hdflush(hp); |
| 712 |
/* release fragment resources */ |
| 713 |
hdrelease(hp->fd); |
| 714 |
/* remove hp from active list */ |
| 715 |
for (i = 0; hdlist[i] != NULL; i++) |
| 716 |
if (hdlist[i] == hp) { |
| 717 |
while ((hdlist[i] = hdlist[i+1]) != NULL) |
| 718 |
i++; |
| 719 |
break; |
| 720 |
} |
| 721 |
free((char *)hp->bl); /* free beam list */ |
| 722 |
free((char *)hp); /* free holodeck struct */ |
| 723 |
} |
