| 1 | #include "fs.h" |
| 2 | |
| 3 | /* NB: not portable! assumes little endian (and probably other things) */ |
| 4 | |
| 5 | #define NIPB (512/sizeof(DInode)) |
| 6 | #define NDPB (512/sizeof(Dirent)) |
| 7 | |
| 8 | /* v6 superblock */ |
| 9 | typedef struct Filsys Filsys; |
| 10 | struct Filsys |
| 11 | { |
| 12 | int16 s_isize; /* size in blocks of I list */ |
| 13 | int16 s_fsize; /* size in blocks of entire volume */ |
| 14 | int16 s_nfree; /* number of in core free blocks (0-100) */ |
| 15 | int16 s_free[100]; /* in core free blocks */ |
| 16 | int16 s_ninode; /* number of in core I nodes (0-100) */ |
| 17 | int16 s_inode[100]; /* in core free I nodes */ |
| 18 | uint8 s_flock; /* lock during free list manipulation */ |
| 19 | uint8 s_ilock; /* lock during I list manipulation */ |
| 20 | uint8 s_fmod; /* super block modified flag */ |
| 21 | uint8 s_ronly; /* mounted read-only flag */ |
| 22 | int16 s_time[2]; /* current date of last update */ |
| 23 | int16 pad[48]; |
| 24 | }; |
| 25 | |
| 26 | /* v6 and PWB/1.0 disk inode */ |
| 27 | struct DInode |
| 28 | { |
| 29 | uint16 i_mode; |
| 30 | int8 i_nlink; |
| 31 | uint8 i_uid; |
| 32 | uint8 i_gid; |
| 33 | uint8 i_size0; |
| 34 | uint16 i_size1; |
| 35 | uint16 i_addr[8]; |
| 36 | uint16 i_atime[2]; |
| 37 | uint16 i_mtime[2]; |
| 38 | }; |
| 39 | |
| 40 | /* modes */ |
| 41 | #define IALLOC 0100000 |
| 42 | #define IFMT 060000 |
| 43 | #define IFDIR 040000 |
| 44 | #define IFCHR 020000 |
| 45 | #define IFBLK 060000 |
| 46 | #define ILARG 010000 |
| 47 | #define ISUID 04000 |
| 48 | #define ISGID 02000 |
| 49 | #define ISVTX 01000 |
| 50 | #define IREAD 0400 |
| 51 | #define IWRITE 0200 |
| 52 | #define IEXEC 0100 |
| 53 | |
| 54 | typedef struct Dirent Dirent; |
| 55 | struct Dirent |
| 56 | { |
| 57 | uint16 inode; |
| 58 | char name[14]; |
| 59 | }; |
| 60 | |
| 61 | Filsys *filesys; |
| 62 | DInode *dinodes; |
| 63 | Inode *inodes; |
| 64 | |
| 65 | #define ISIZE(ip) ((ip)->i_size0<<16 | (ip)->i_size1) |
| 66 | int32 |
| 67 | pdplong(void *p) |
| 68 | { |
| 69 | uint8 *up; |
| 70 | uint32 ui; |
| 71 | up = p; |
| 72 | ui = up[1]<<24 | up[0]<<16 | up[3]<<8 | up[2]; |
| 73 | return *(int32*)&ui; |
| 74 | } |
| 75 | |
| 76 | void |
| 77 | setpdplong(void *p, int32 i) |
| 78 | { |
| 79 | uint8 *up; |
| 80 | uint32 ui; |
| 81 | up = p; |
| 82 | ui = *(uint32*)&i; |
| 83 | up[1] = ui>>24; |
| 84 | up[0] = ui>>16; |
| 85 | up[3] = ui>>8; |
| 86 | up[2] = ui; |
| 87 | } |
| 88 | |
| 89 | void |
| 90 | setint24(void *p, int32 i) |
| 91 | { |
| 92 | uint8 *up; |
| 93 | uint32 ui; |
| 94 | up = p; |
| 95 | ui = *(uint32*)&i; |
| 96 | up[0] = ui>>16; |
| 97 | up[2] = ui>>8; |
| 98 | up[1] = ui; |
| 99 | } |
| 100 | |
| 101 | void *bget(int n) { return &fsdata[n*512]; } |
| 102 | |
| 103 | /* returns a free block or 0 */ |
| 104 | int |
| 105 | balloc(void) |
| 106 | { |
| 107 | int i, bno; |
| 108 | uint16 *b; |
| 109 | filesys->s_nfree--; |
| 110 | if(filesys->s_nfree < 0 || filesys->s_nfree >= 100){ |
| 111 | printf("bad free count\n"); |
| 112 | return 0; |
| 113 | } |
| 114 | bno = filesys->s_free[filesys->s_nfree]; |
| 115 | filesys->s_free[filesys->s_nfree] = 0; |
| 116 | if(bno == 0) |
| 117 | return 0; |
| 118 | if(bno < filesys->s_isize+2 || bno >= filesys->s_fsize){ |
| 119 | printf("bad free block (%d)\n", bno); |
| 120 | return 0; |
| 121 | } |
| 122 | if(filesys->s_nfree <= 0){ |
| 123 | b = bget(bno); |
| 124 | filesys->s_nfree = b[0]; |
| 125 | for(i = 0; i < 100; i++) |
| 126 | filesys->s_free[i] = b[i+1]; |
| 127 | } |
| 128 | return bno; |
| 129 | } |
| 130 | |
| 131 | void |
| 132 | bfree(int bno) |
| 133 | { |
| 134 | int i; |
| 135 | uint16 *b; |
| 136 | |
| 137 | printf("freeing block\n"); |
| 138 | if(filesys->s_nfree >= 100){ |
| 139 | b = bget(bno); |
| 140 | b[0] = filesys->s_nfree; |
| 141 | for(i = 0; i < 100; i++) |
| 142 | b[i+1] = filesys->s_free[i]; |
| 143 | filesys->s_nfree = 0; |
| 144 | } |
| 145 | filesys->s_free[filesys->s_nfree] = bno; |
| 146 | filesys->s_nfree++; |
| 147 | } |
| 148 | |
| 149 | int |
| 150 | zalloc(void) |
| 151 | { |
| 152 | int bn; |
| 153 | bn = balloc(); |
| 154 | if(bn) |
| 155 | memset(bget(bn), 0, 512); |
| 156 | return bn; |
| 157 | } |
| 158 | |
| 159 | /* returns a free inode or 0 */ |
| 160 | int |
| 161 | ialloc(void) |
| 162 | { |
| 163 | int ino; |
| 164 | DInode *ip; |
| 165 | int i, j; |
| 166 | |
| 167 | if(filesys->s_ninode <= 0){ |
| 168 | ino = 0; |
| 169 | for(i = 0; i < filesys->s_isize; i++) |
| 170 | for(j = 0; j < NIPB; j++){ |
| 171 | ino++; |
| 172 | ip = &dinodes[ino]; |
| 173 | if(ip->i_mode) |
| 174 | continue; |
| 175 | filesys->s_inode[filesys->s_ninode++] = ino; |
| 176 | if(filesys->s_ninode >= 100) |
| 177 | goto brk; |
| 178 | } |
| 179 | } |
| 180 | brk: |
| 181 | if(filesys->s_ninode > 0){ |
| 182 | ino = filesys->s_inode[--filesys->s_ninode]; |
| 183 | return ino; |
| 184 | } |
| 185 | return 0; |
| 186 | } |
| 187 | |
| 188 | void |
| 189 | ifree(int ino) |
| 190 | { |
| 191 | printf("freeing inode\n"); |
| 192 | if(filesys->s_ninode >= 100) |
| 193 | return; |
| 194 | filesys->s_inode[filesys->s_ninode++] = ino; |
| 195 | } |
| 196 | |
| 197 | void |
| 198 | itrunc(DInode *ip) |
| 199 | { |
| 200 | int i; |
| 201 | uint16 *bp, *cp, *dp, *ep; |
| 202 | |
| 203 | if(ip->i_mode & (IFCHR|IFBLK)) |
| 204 | return; |
| 205 | for(i = 7; i >= 0; i--) |
| 206 | if(ip->i_addr[i]){ |
| 207 | if(ip->i_mode & ILARG){ |
| 208 | bp = bget(ip->i_addr[i]); |
| 209 | for(cp = &bp[255]; cp >= bp; cp--) |
| 210 | if(*cp){ |
| 211 | if(i == 7){ |
| 212 | dp = bget(*cp); |
| 213 | for(ep = &dp[255]; ep >= dp; ep--) |
| 214 | if(*ep) |
| 215 | bfree(*ep); |
| 216 | } |
| 217 | bfree(*cp); |
| 218 | } |
| 219 | } |
| 220 | bfree(ip->i_addr[i]); |
| 221 | ip->i_addr[i] = 0; |
| 222 | } |
| 223 | ip->i_mode &= ~ILARG; |
| 224 | setint24(&ip->i_size0, 0); |
| 225 | } |
| 226 | |
| 227 | void |
| 228 | dcheck(void) |
| 229 | { |
| 230 | Filsys fs; |
| 231 | int i; |
| 232 | |
| 233 | fs = *filesys; |
| 234 | i = 0; |
| 235 | while(balloc()) |
| 236 | i++; |
| 237 | printf("free: %d\n", i); |
| 238 | *filesys = fs; |
| 239 | } |
| 240 | |
| 241 | int |
| 242 | bmap(DInode *ip, uint bn) |
| 243 | { |
| 244 | uint i; |
| 245 | uint nb; |
| 246 | uint16 *b; |
| 247 | |
| 248 | if(bn & ~077777) |
| 249 | return 0; |
| 250 | |
| 251 | if((ip->i_mode & ILARG) == 0){ |
| 252 | |
| 253 | /* small file, direct fetch */ |
| 254 | |
| 255 | if(bn & ~7){ |
| 256 | /* convert to large */ |
| 257 | nb = zalloc(); |
| 258 | if(nb == 0) |
| 259 | return 0; |
| 260 | b = bget(nb); |
| 261 | for(i = 0; i < 8; i++){ |
| 262 | b[i] = ip->i_addr[i]; |
| 263 | ip->i_addr[i] = 0; |
| 264 | } |
| 265 | ip->i_addr[0] = nb; |
| 266 | ip->i_mode |= ILARG; |
| 267 | goto large; |
| 268 | } |
| 269 | |
| 270 | nb = ip->i_addr[bn]; |
| 271 | if(nb == 0){ |
| 272 | nb = zalloc(); |
| 273 | if(nb == 0) |
| 274 | return 0; |
| 275 | ip->i_addr[bn] = nb; |
| 276 | } |
| 277 | return nb; |
| 278 | } |
| 279 | |
| 280 | /* large file, 7 indirect blocks */ |
| 281 | |
| 282 | large: |
| 283 | i = bn>>8; |
| 284 | if(i > 7) |
| 285 | i = 7; |
| 286 | nb = ip->i_addr[i]; |
| 287 | if(nb == 0){ |
| 288 | nb = zalloc(); |
| 289 | if(nb == 0) |
| 290 | return 0; |
| 291 | ip->i_addr[bn] = nb; |
| 292 | } |
| 293 | b = bget(nb); |
| 294 | |
| 295 | if(i == 7){ |
| 296 | |
| 297 | /* huge file, double indirect last block */ |
| 298 | |
| 299 | i = (bn>>8) - 7; |
| 300 | nb = b[i&0377]; |
| 301 | if(nb == 0){ |
| 302 | nb = zalloc(); |
| 303 | if(nb == 0) |
| 304 | return 0; |
| 305 | b[i&0377] = nb; |
| 306 | } |
| 307 | b = bget(nb); |
| 308 | } |
| 309 | |
| 310 | nb = b[bn&0377]; |
| 311 | return nb; |
| 312 | }; |
| 313 | |
| 314 | uint8* |
| 315 | getblock(DInode *ip, uint bn) |
| 316 | { |
| 317 | bn = bmap(ip, bn); |
| 318 | if(bn == 0) |
| 319 | return nil; |
| 320 | return bget(bn); |
| 321 | } |
| 322 | |
| 323 | void |
| 324 | fs_init(void) |
| 325 | { |
| 326 | int i, ni; |
| 327 | |
| 328 | filesys = bget(1); |
| 329 | dinodes = (DInode*)bget(2) - 1; |
| 330 | ni = filesys->s_isize*NIPB + 1; |
| 331 | inodes = malloc(ni*sizeof(Inode)); |
| 332 | for(i = 0; i < ni; i++){ |
| 333 | inodes[i].ino = i; |
| 334 | inodes[i].count = 0; |
| 335 | inodes[i].i = &dinodes[i]; |
| 336 | } |
| 337 | } |
| 338 | |
| 339 | int |
| 340 | fs_open(uint ino, int flags) |
| 341 | { |
| 342 | DInode *ip; |
| 343 | |
| 344 | ip = &dinodes[ino]; |
| 345 | if((ip->i_mode & IFMT) == IFDIR) |
| 346 | return EISDIR; |
| 347 | // if((flags & 3) != O_RDONLY) |
| 348 | // return EACCES; |
| 349 | return 0; |
| 350 | } |
| 351 | |
| 352 | int |
| 353 | fs_stat(uint ino, struct stat *stbuf) |
| 354 | { |
| 355 | DInode *ip; |
| 356 | ip = &dinodes[ino]; |
| 357 | |
| 358 | stbuf->st_ino = ino; |
| 359 | if((ip->i_mode & IFMT) == IFDIR) |
| 360 | stbuf->st_mode = S_IFDIR; |
| 361 | else if((ip->i_mode & IFMT) == IFCHR) |
| 362 | stbuf->st_mode = S_IFCHR; |
| 363 | else if((ip->i_mode & IFMT) == IFBLK) |
| 364 | stbuf->st_mode = S_IFBLK; |
| 365 | else |
| 366 | stbuf->st_mode = S_IFREG; |
| 367 | stbuf->st_mode |= ip->i_mode & 0777; |
| 368 | stbuf->st_nlink = ip->i_nlink; |
| 369 | stbuf->st_size = ISIZE(ip); |
| 370 | if((ip->i_mode & IFMT) == IFCHR || |
| 371 | (ip->i_mode & IFMT) == IFBLK) |
| 372 | stbuf->st_rdev = makedev(ip->i_addr[0]>>8 & 0xFF, ip->i_addr[0]&0xFF); |
| 373 | stbuf->st_uid = ip->i_uid; |
| 374 | stbuf->st_gid = ip->i_gid; |
| 375 | stbuf->st_atime = pdplong(ip->i_atime); |
| 376 | stbuf->st_mtime = pdplong(ip->i_mtime); |
| 377 | |
| 378 | return 0; |
| 379 | } |
| 380 | |
| 381 | int |
| 382 | fs_atime(uint ino, int32 time) |
| 383 | { |
| 384 | DInode *ip; |
| 385 | ip = &dinodes[ino]; |
| 386 | setpdplong(ip->i_atime, time); |
| 387 | return 0; |
| 388 | } |
| 389 | |
| 390 | int |
| 391 | fs_mtime(uint ino, int32 time) |
| 392 | { |
| 393 | DInode *ip; |
| 394 | ip = &dinodes[ino]; |
| 395 | setpdplong(ip->i_mtime, time); |
| 396 | return 0; |
| 397 | } |
| 398 | |
| 399 | int |
| 400 | fs_uid(uint ino, int32 uid) |
| 401 | { |
| 402 | DInode *ip; |
| 403 | ip = &dinodes[ino]; |
| 404 | ip->i_uid = uid; |
| 405 | return 0; |
| 406 | } |
| 407 | |
| 408 | int |
| 409 | fs_gid(uint ino, int32 gid) |
| 410 | { |
| 411 | DInode *ip; |
| 412 | ip = &dinodes[ino]; |
| 413 | ip->i_gid = gid; |
| 414 | return 0; |
| 415 | } |
| 416 | |
| 417 | int |
| 418 | fs_read(uint ino, void *vdst, int offset, int len) |
| 419 | { |
| 420 | DInode *ip; |
| 421 | int bn; |
| 422 | uint8 *b; |
| 423 | int isize; |
| 424 | int n; |
| 425 | uint8 *dst; |
| 426 | |
| 427 | ip = &dinodes[ino]; |
| 428 | dst = vdst; |
| 429 | isize = ISIZE(ip); |
| 430 | if(offset + len > isize) |
| 431 | len = isize - offset; |
| 432 | if(len <= 0) |
| 433 | return 0; |
| 434 | |
| 435 | bn = offset/512; |
| 436 | offset %= 512; |
| 437 | |
| 438 | b = getblock(ip, bn); |
| 439 | if(b == nil) |
| 440 | /* TODO: handle gracefully */ |
| 441 | panic("no block"); |
| 442 | |
| 443 | if(len < 512-offset){ |
| 444 | /* smaller than block */ |
| 445 | memcpy(dst, b+offset, len); |
| 446 | return len; |
| 447 | } |
| 448 | |
| 449 | /* at least one block */ |
| 450 | memcpy(dst, b+offset, 512-offset); |
| 451 | n = 512-offset; |
| 452 | len -= n; |
| 453 | dst += n; |
| 454 | while(len > 0){ |
| 455 | bn++; |
| 456 | b = getblock(ip, bn); |
| 457 | if(b == nil) |
| 458 | /* TODO: handle gracefully */ |
| 459 | panic("no block"); |
| 460 | memcpy(dst, b, len > 512 ? 512 : len); |
| 461 | n += len > 512 ? 512 : len; |
| 462 | len -= 512; |
| 463 | dst += 512; |
| 464 | } |
| 465 | return n; |
| 466 | } |
| 467 | |
| 468 | int |
| 469 | fs_write(uint ino, void *vsrc, int offset, int len) |
| 470 | { |
| 471 | DInode *ip; |
| 472 | int bn; |
| 473 | uint8 *b; |
| 474 | int n; |
| 475 | int32 size; |
| 476 | uint8 *src; |
| 477 | |
| 478 | ip = &dinodes[ino]; |
| 479 | src = vsrc; |
| 480 | size = ISIZE(ip); |
| 481 | // TODO: make this better: |
| 482 | if(offset+len > size) |
| 483 | setint24(&ip->i_size0, offset+len); |
| 484 | if(len <= 0) |
| 485 | return 0; |
| 486 | |
| 487 | bn = offset/512; |
| 488 | offset %= 512; |
| 489 | |
| 490 | b = getblock(ip, bn); |
| 491 | if(b == nil) |
| 492 | /* TODO: handle gracefully */ |
| 493 | panic("no block"); |
| 494 | |
| 495 | if(len < 512-offset){ |
| 496 | /* smaller than block */ |
| 497 | memcpy(b+offset, src, len); |
| 498 | return len; |
| 499 | } |
| 500 | |
| 501 | /* at least one block */ |
| 502 | memcpy(b+offset, src, 512-offset); |
| 503 | n = 512-offset; |
| 504 | len -= n; |
| 505 | src += n; |
| 506 | while(len > 0){ |
| 507 | bn++; |
| 508 | b = getblock(ip, bn); |
| 509 | if(b == nil) |
| 510 | /* TODO: handle gracefully */ |
| 511 | panic("no block"); |
| 512 | memcpy(b, src, len > 512 ? 512 : len); |
| 513 | n += len > 512 ? 512 : len; |
| 514 | len -= 512; |
| 515 | src += 512; |
| 516 | } |
| 517 | return n; |
| 518 | } |
| 519 | |
| 520 | /* return a malloc'd array of dirents for a given inode */ |
| 521 | struct dirent* |
| 522 | fs_readdir(uint ino) |
| 523 | { |
| 524 | DInode *ip; |
| 525 | struct dirent *des, *dp; |
| 526 | int size; |
| 527 | int ndes; |
| 528 | Dirent de; |
| 529 | int offset; |
| 530 | |
| 531 | ip = &dinodes[ino]; |
| 532 | if((ip->i_mode & IFDIR) == 0) |
| 533 | return nil; |
| 534 | |
| 535 | size = ISIZE(ip); |
| 536 | ndes = size/sizeof(Dirent); |
| 537 | des = malloc((ndes+1)*sizeof(struct dirent)); |
| 538 | |
| 539 | offset = 0; |
| 540 | dp = des; |
| 541 | while(fs_read(ino, &de, offset, sizeof(Dirent)) == sizeof(Dirent)){ |
| 542 | if(de.inode){ |
| 543 | dp->d_ino = de.inode; |
| 544 | memcpy(dp->d_name, de.name, 14); |
| 545 | dp->d_name[14] = '\0'; |
| 546 | dp++; |
| 547 | } |
| 548 | offset += sizeof(Dirent); |
| 549 | } |
| 550 | dp->d_ino = 0; |
| 551 | dp->d_name[0] = '\0'; |
| 552 | |
| 553 | return des; |
| 554 | } |
| 555 | |
| 556 | static int |
| 557 | lookup(uint ino, const char *name, Dirent *de) |
| 558 | { |
| 559 | int offset; |
| 560 | |
| 561 | assert(de); |
| 562 | offset = 0; |
| 563 | while(fs_read(ino, de, offset, sizeof(Dirent)) == sizeof(Dirent)){ |
| 564 | if(de->inode) |
| 565 | if(strcmp(de->name, name) == 0) |
| 566 | return offset; |
| 567 | offset += sizeof(Dirent); |
| 568 | } |
| 569 | memset(de, 0, sizeof(Dirent)); |
| 570 | return -1; |
| 571 | } |
| 572 | |
| 573 | static int |
| 574 | allocdirent(uint ino) |
| 575 | { |
| 576 | Dirent de; |
| 577 | int offset; |
| 578 | |
| 579 | offset = 0; |
| 580 | while(fs_read(ino, &de, offset, sizeof(Dirent)) == sizeof(Dirent)){ |
| 581 | if(de.inode == 0) |
| 582 | return offset; |
| 583 | offset += sizeof(Dirent); |
| 584 | } |
| 585 | memset(&de, 0, sizeof(Dirent)); |
| 586 | fs_write(ino, &de, offset, sizeof(Dirent)); |
| 587 | return offset; |
| 588 | } |
| 589 | |
| 590 | int |
| 591 | fs_link(uint ino, uint parent, const char *name) |
| 592 | { |
| 593 | Dirent de; |
| 594 | int offset; |
| 595 | |
| 596 | offset = allocdirent(parent); |
| 597 | /* TODO: can't happen right now */ |
| 598 | if(offset < 0) |
| 599 | return ENOSPC; |
| 600 | memset(&de, 0, sizeof(Dirent)); |
| 601 | de.inode = ino; |
| 602 | strncpy(de.name, name, 14); |
| 603 | fs_write(parent, &de, offset, sizeof(de)); |
| 604 | fs_mtime(ino, time(nil)); |
| 605 | fs_atime(ino, time(nil)); |
| 606 | dinodes[ino].i_nlink++; |
| 607 | |
| 608 | return 0; |
| 609 | } |
| 610 | |
| 611 | int |
| 612 | fs_mknod(uint parent, const char *name, mode_t mode, dev_t rdev, uint *newino) |
| 613 | { |
| 614 | uint ino; |
| 615 | DInode *ip, *ipp; |
| 616 | int offset; |
| 617 | Dirent de; |
| 618 | |
| 619 | USED(rdev); |
| 620 | // TODO: support more files |
| 621 | if((mode & S_IFMT) != S_IFREG && |
| 622 | (mode & S_IFMT) != S_IFDIR) |
| 623 | return EACCES; |
| 624 | |
| 625 | ino = ialloc(); |
| 626 | if(ino == 0) |
| 627 | return ENOSPC; |
| 628 | ip = &dinodes[ino]; |
| 629 | memset(ip, 0, sizeof(DInode)); |
| 630 | ip->i_mode = (mode&0777) | IALLOC; |
| 631 | if((mode & S_IFMT) == S_IFDIR) |
| 632 | ip->i_mode |= IFDIR; |
| 633 | else if((mode & S_IFMT) == S_IFCHR) |
| 634 | ip->i_mode |= IFCHR; |
| 635 | else if((mode & S_IFMT) == S_IFBLK) |
| 636 | ip->i_mode |= IFBLK; |
| 637 | if((ip->i_mode & IFMT) == IFCHR || |
| 638 | (ip->i_mode & IFMT) == IFBLK) |
| 639 | ip->i_addr[0] = |
| 640 | major(rdev)<<8 & 0xFF00 | minor(rdev) & 0xFF; |
| 641 | |
| 642 | ipp = &dinodes[parent]; |
| 643 | assert((ipp->i_mode & IFMT) == IFDIR); |
| 644 | |
| 645 | offset = allocdirent(parent); |
| 646 | /* TODO: can't happen right now */ |
| 647 | if(offset < 0){ |
| 648 | ip->i_mode = 0; |
| 649 | return ENOSPC; |
| 650 | } |
| 651 | |
| 652 | ip->i_nlink = 1; |
| 653 | memset(&de, 0, sizeof(Dirent)); |
| 654 | de.inode = ino; |
| 655 | strncpy(de.name, name, 14); |
| 656 | fs_write(parent, &de, offset, sizeof(de)); |
| 657 | fs_mtime(ino, time(nil)); |
| 658 | fs_atime(ino, time(nil)); |
| 659 | |
| 660 | if(newino) |
| 661 | *newino = ino; |
| 662 | printf("making node %s %o\n", name, mode); |
| 663 | return 0; |
| 664 | } |
| 665 | |
| 666 | int |
| 667 | fs_mkdir(uint parent, const char *name, mode_t mode) |
| 668 | { |
| 669 | int bn; |
| 670 | int ino; |
| 671 | int ret; |
| 672 | DInode *ip; |
| 673 | Dirent des[2]; |
| 674 | |
| 675 | /* Make sure we have space */ |
| 676 | bn = balloc(); |
| 677 | if(bn == 0) |
| 678 | return ENOSPC; |
| 679 | ret = fs_mknod(parent, name, mode | S_IFDIR, 0, &ino); |
| 680 | if(ret){ |
| 681 | bfree(bn); |
| 682 | return ret; |
| 683 | } |
| 684 | ip = &dinodes[ino]; |
| 685 | ip->i_addr[0] = bn; |
| 686 | |
| 687 | memset(des, 0, 2*sizeof(Dirent)); |
| 688 | des[0].inode = ino; |
| 689 | strcpy(des[0].name, "."); |
| 690 | ip->i_nlink++; |
| 691 | des[1].inode = parent; |
| 692 | strcpy(des[1].name, ".."); |
| 693 | dinodes[parent].i_nlink++; |
| 694 | fs_write(ino, des, 0, 2*sizeof(Dirent)); |
| 695 | return 0; |
| 696 | } |
| 697 | |
| 698 | Inode* |
| 699 | fs_iget(uint ino) |
| 700 | { |
| 701 | Inode *ip; |
| 702 | ip = &inodes[ino]; |
| 703 | ip->count++; |
| 704 | return ip; |
| 705 | } |
| 706 | |
| 707 | void |
| 708 | fs_iput(Inode *ip) |
| 709 | { |
| 710 | assert(ip->count > 0); |
| 711 | ip->count--; |
| 712 | if(ip->count == 0) |
| 713 | if(ip->i->i_nlink <= 0){ |
| 714 | printf("truncating inode %d (%d)\n", ip->ino, ip->i->i_nlink); |
| 715 | itrunc(ip->i); |
| 716 | ip->i->i_mode = 0; |
| 717 | ifree(ip->ino); |
| 718 | } |
| 719 | } |
| 720 | |
| 721 | int |
| 722 | fs_unlink(uint parent, const char *name) |
| 723 | { |
| 724 | Dirent de; |
| 725 | int offset; |
| 726 | |
| 727 | offset = lookup(parent, name, &de); |
| 728 | if(offset < 0) |
| 729 | /* shouldn't happen */ |
| 730 | return 1; |
| 731 | dinodes[de.inode].i_nlink--; |
| 732 | |
| 733 | de.inode = 0; |
| 734 | fs_write(parent, &de, offset, sizeof(Dirent)); |
| 735 | return 0; |
| 736 | } |