1 /* $FreeBSD$ */ 2 /* $NetBSD: msdosfs_vnops.c,v 1.68 1998/02/10 14:10:04 mrg Exp $ */ 3 4 /*- 5 * Copyright (C) 1994, 1995, 1997 Wolfgang Solfrank. 6 * Copyright (C) 1994, 1995, 1997 TooLs GmbH. 7 * All rights reserved. 8 * Original code by Paul Popelka (paulp@uts.amdahl.com) (see below). 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by TooLs GmbH. 21 * 4. The name of TooLs GmbH may not be used to endorse or promote products 22 * derived from this software without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR 25 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES 26 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. 27 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 28 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, 29 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; 30 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, 31 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR 32 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF 33 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 34 */ 35 /* 36 * Written by Paul Popelka (paulp@uts.amdahl.com) 37 * 38 * You can do anything you want with this software, just don't say you wrote 39 * it, and don't remove this notice. 40 * 41 * This software is provided "as is". 42 * 43 * The author supplies this software to be publicly redistributed on the 44 * understanding that the author is not responsible for the correct 45 * functioning of this software in any circumstances and is not liable for 46 * any damages caused by this software. 47 * 48 * October 1992 49 */ 50 51 #include <sys/param.h> 52 #include <sys/systm.h> 53 #include <sys/namei.h> 54 #include <sys/resourcevar.h> /* defines plimit structure in proc struct */ 55 #include <sys/kernel.h> 56 #include <sys/stat.h> 57 #include <sys/bio.h> 58 #include <sys/buf.h> 59 #include <sys/proc.h> 60 #include <sys/mount.h> 61 #include <sys/unistd.h> 62 #include <sys/vnode.h> 63 #include <sys/malloc.h> 64 #include <sys/dirent.h> 65 #include <sys/signalvar.h> 66 67 #include <vm/vm.h> 68 #include <vm/vm_extern.h> 69 #include <vm/vnode_pager.h> 70 71 #include <machine/mutex.h> 72 73 #include <msdosfs/bpb.h> 74 #include <msdosfs/direntry.h> 75 #include <msdosfs/denode.h> 76 #include <msdosfs/msdosfsmount.h> 77 #include <msdosfs/fat.h> 78 79 #define DOS_FILESIZE_MAX 0xffffffff 80 81 /* 82 * Prototypes for MSDOSFS vnode operations 83 */ 84 static int msdosfs_create __P((struct vop_create_args *)); 85 static int msdosfs_mknod __P((struct vop_mknod_args *)); 86 static int msdosfs_close __P((struct vop_close_args *)); 87 static int msdosfs_access __P((struct vop_access_args *)); 88 static int msdosfs_getattr __P((struct vop_getattr_args *)); 89 static int msdosfs_setattr __P((struct vop_setattr_args *)); 90 static int msdosfs_read __P((struct vop_read_args *)); 91 static int msdosfs_write __P((struct vop_write_args *)); 92 static int msdosfs_fsync __P((struct vop_fsync_args *)); 93 static int msdosfs_remove __P((struct vop_remove_args *)); 94 static int msdosfs_link __P((struct vop_link_args *)); 95 static int msdosfs_rename __P((struct vop_rename_args *)); 96 static int msdosfs_mkdir __P((struct vop_mkdir_args *)); 97 static int msdosfs_rmdir __P((struct vop_rmdir_args *)); 98 static int msdosfs_symlink __P((struct vop_symlink_args *)); 99 static int msdosfs_readdir __P((struct vop_readdir_args *)); 100 static int msdosfs_bmap __P((struct vop_bmap_args *)); 101 static int msdosfs_strategy __P((struct vop_strategy_args *)); 102 static int msdosfs_print __P((struct vop_print_args *)); 103 static int msdosfs_pathconf __P((struct vop_pathconf_args *ap)); 104 static int msdosfs_getpages __P((struct vop_getpages_args *)); 105 static int msdosfs_putpages __P((struct vop_putpages_args *)); 106 107 /* 108 * Some general notes: 109 * 110 * In the ufs filesystem the inodes, superblocks, and indirect blocks are 111 * read/written using the vnode for the filesystem. Blocks that represent 112 * the contents of a file are read/written using the vnode for the file 113 * (including directories when they are read/written as files). This 114 * presents problems for the dos filesystem because data that should be in 115 * an inode (if dos had them) resides in the directory itself. Since we 116 * must update directory entries without the benefit of having the vnode 117 * for the directory we must use the vnode for the filesystem. This means 118 * that when a directory is actually read/written (via read, write, or 119 * readdir, or seek) we must use the vnode for the filesystem instead of 120 * the vnode for the directory as would happen in ufs. This is to insure we 121 * retreive the correct block from the buffer cache since the hash value is 122 * based upon the vnode address and the desired block number. 123 */ 124 125 /* 126 * Create a regular file. On entry the directory to contain the file being 127 * created is locked. We must release before we return. We must also free 128 * the pathname buffer pointed at by cnp->cn_pnbuf, always on error, or 129 * only if the SAVESTART bit in cn_flags is clear on success. 130 */ 131 static int 132 msdosfs_create(ap) 133 struct vop_create_args /* { 134 struct vnode *a_dvp; 135 struct vnode **a_vpp; 136 struct componentname *a_cnp; 137 struct vattr *a_vap; 138 } */ *ap; 139 { 140 struct componentname *cnp = ap->a_cnp; 141 struct denode ndirent; 142 struct denode *dep; 143 struct denode *pdep = VTODE(ap->a_dvp); 144 struct timespec ts; 145 int error; 146 147 #ifdef MSDOSFS_DEBUG 148 printf("msdosfs_create(cnp %p, vap %p\n", cnp, ap->a_vap); 149 #endif 150 151 /* 152 * If this is the root directory and there is no space left we 153 * can't do anything. This is because the root directory can not 154 * change size. 155 */ 156 if (pdep->de_StartCluster == MSDOSFSROOT 157 && pdep->de_fndoffset >= pdep->de_FileSize) { 158 error = ENOSPC; 159 goto bad; 160 } 161 162 /* 163 * Create a directory entry for the file, then call createde() to 164 * have it installed. NOTE: DOS files are always executable. We 165 * use the absence of the owner write bit to make the file 166 * readonly. 167 */ 168 #ifdef DIAGNOSTIC 169 if ((cnp->cn_flags & HASBUF) == 0) 170 panic("msdosfs_create: no name"); 171 #endif 172 bzero(&ndirent, sizeof(ndirent)); 173 error = uniqdosname(pdep, cnp, ndirent.de_Name); 174 if (error) 175 goto bad; 176 177 ndirent.de_Attributes = (ap->a_vap->va_mode & VWRITE) ? 178 ATTR_ARCHIVE : ATTR_ARCHIVE | ATTR_READONLY; 179 ndirent.de_LowerCase = 0; 180 ndirent.de_StartCluster = 0; 181 ndirent.de_FileSize = 0; 182 ndirent.de_dev = pdep->de_dev; 183 ndirent.de_devvp = pdep->de_devvp; 184 ndirent.de_pmp = pdep->de_pmp; 185 ndirent.de_flag = DE_ACCESS | DE_CREATE | DE_UPDATE; 186 getnanotime(&ts); 187 DETIMES(&ndirent, &ts, &ts, &ts); 188 error = createde(&ndirent, pdep, &dep, cnp); 189 if (error) 190 goto bad; 191 *ap->a_vpp = DETOV(dep); 192 return (0); 193 194 bad: 195 return (error); 196 } 197 198 static int 199 msdosfs_mknod(ap) 200 struct vop_mknod_args /* { 201 struct vnode *a_dvp; 202 struct vnode **a_vpp; 203 struct componentname *a_cnp; 204 struct vattr *a_vap; 205 } */ *ap; 206 { 207 208 switch (ap->a_vap->va_type) { 209 case VDIR: 210 return (msdosfs_mkdir((struct vop_mkdir_args *)ap)); 211 break; 212 213 case VREG: 214 return (msdosfs_create((struct vop_create_args *)ap)); 215 break; 216 217 default: 218 return (EINVAL); 219 } 220 /* NOTREACHED */ 221 } 222 223 static int 224 msdosfs_close(ap) 225 struct vop_close_args /* { 226 struct vnode *a_vp; 227 int a_fflag; 228 struct ucred *a_cred; 229 struct proc *a_p; 230 } */ *ap; 231 { 232 struct vnode *vp = ap->a_vp; 233 struct denode *dep = VTODE(vp); 234 struct timespec ts; 235 236 mtx_lock(&vp->v_interlock); 237 if (vp->v_usecount > 1) { 238 getnanotime(&ts); 239 DETIMES(dep, &ts, &ts, &ts); 240 } 241 mtx_unlock(&vp->v_interlock); 242 return 0; 243 } 244 245 static int 246 msdosfs_access(ap) 247 struct vop_access_args /* { 248 struct vnode *a_vp; 249 int a_mode; 250 struct ucred *a_cred; 251 struct proc *a_p; 252 } */ *ap; 253 { 254 struct vnode *vp = ap->a_vp; 255 struct denode *dep = VTODE(ap->a_vp); 256 struct msdosfsmount *pmp = dep->de_pmp; 257 mode_t file_mode, mode = ap->a_mode; 258 259 file_mode = (S_IXUSR|S_IXGRP|S_IXOTH) | (S_IRUSR|S_IRGRP|S_IROTH) | 260 ((dep->de_Attributes & ATTR_READONLY) ? 0 : (S_IWUSR|S_IWGRP|S_IWOTH)); 261 file_mode &= pmp->pm_mask; 262 263 /* 264 * Disallow write attempts on read-only file systems; 265 * unless the file is a socket, fifo, or a block or 266 * character device resident on the file system. 267 */ 268 if (mode & VWRITE) { 269 switch (vp->v_type) { 270 case VDIR: 271 case VLNK: 272 case VREG: 273 if (vp->v_mount->mnt_flag & MNT_RDONLY) 274 return (EROFS); 275 break; 276 default: 277 break; 278 } 279 } 280 281 return (vaccess(vp->v_type, file_mode, pmp->pm_uid, pmp->pm_gid, 282 ap->a_mode, ap->a_cred, NULL)); 283 } 284 285 static int 286 msdosfs_getattr(ap) 287 struct vop_getattr_args /* { 288 struct vnode *a_vp; 289 struct vattr *a_vap; 290 struct ucred *a_cred; 291 struct proc *a_p; 292 } */ *ap; 293 { 294 struct denode *dep = VTODE(ap->a_vp); 295 struct msdosfsmount *pmp = dep->de_pmp; 296 struct vattr *vap = ap->a_vap; 297 mode_t mode; 298 struct timespec ts; 299 u_long dirsperblk = pmp->pm_BytesPerSec / sizeof(struct direntry); 300 u_long fileid; 301 302 getnanotime(&ts); 303 DETIMES(dep, &ts, &ts, &ts); 304 vap->va_fsid = dev2udev(dep->de_dev); 305 /* 306 * The following computation of the fileid must be the same as that 307 * used in msdosfs_readdir() to compute d_fileno. If not, pwd 308 * doesn't work. 309 */ 310 if (dep->de_Attributes & ATTR_DIRECTORY) { 311 fileid = cntobn(pmp, dep->de_StartCluster) * dirsperblk; 312 if (dep->de_StartCluster == MSDOSFSROOT) 313 fileid = 1; 314 } else { 315 fileid = cntobn(pmp, dep->de_dirclust) * dirsperblk; 316 if (dep->de_dirclust == MSDOSFSROOT) 317 fileid = roottobn(pmp, 0) * dirsperblk; 318 fileid += dep->de_diroffset / sizeof(struct direntry); 319 } 320 vap->va_fileid = fileid; 321 if ((dep->de_Attributes & ATTR_READONLY) == 0) 322 mode = S_IRWXU|S_IRWXG|S_IRWXO; 323 else 324 mode = S_IRUSR|S_IXUSR|S_IRGRP|S_IXGRP|S_IROTH|S_IXOTH; 325 vap->va_mode = mode & pmp->pm_mask; 326 vap->va_uid = pmp->pm_uid; 327 vap->va_gid = pmp->pm_gid; 328 vap->va_nlink = 1; 329 vap->va_rdev = 0; 330 vap->va_size = dep->de_FileSize; 331 dos2unixtime(dep->de_MDate, dep->de_MTime, 0, &vap->va_mtime); 332 if (pmp->pm_flags & MSDOSFSMNT_LONGNAME) { 333 dos2unixtime(dep->de_ADate, 0, 0, &vap->va_atime); 334 dos2unixtime(dep->de_CDate, dep->de_CTime, dep->de_CHun, &vap->va_ctime); 335 } else { 336 vap->va_atime = vap->va_mtime; 337 vap->va_ctime = vap->va_mtime; 338 } 339 vap->va_flags = 0; 340 if ((dep->de_Attributes & ATTR_ARCHIVE) == 0) 341 vap->va_flags |= SF_ARCHIVED; 342 vap->va_gen = 0; 343 vap->va_blocksize = pmp->pm_bpcluster; 344 vap->va_bytes = 345 (dep->de_FileSize + pmp->pm_crbomask) & ~pmp->pm_crbomask; 346 vap->va_type = ap->a_vp->v_type; 347 vap->va_filerev = dep->de_modrev; 348 return (0); 349 } 350 351 static int 352 msdosfs_setattr(ap) 353 struct vop_setattr_args /* { 354 struct vnode *a_vp; 355 struct vattr *a_vap; 356 struct ucred *a_cred; 357 struct proc *a_p; 358 } */ *ap; 359 { 360 struct vnode *vp = ap->a_vp; 361 struct denode *dep = VTODE(ap->a_vp); 362 struct msdosfsmount *pmp = dep->de_pmp; 363 struct vattr *vap = ap->a_vap; 364 struct ucred *cred = ap->a_cred; 365 int error = 0; 366 367 #ifdef MSDOSFS_DEBUG 368 printf("msdosfs_setattr(): vp %p, vap %p, cred %p, p %p\n", 369 ap->a_vp, vap, cred, ap->a_p); 370 #endif 371 372 /* 373 * Check for unsettable attributes. 374 */ 375 if ((vap->va_type != VNON) || (vap->va_nlink != VNOVAL) || 376 (vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) || 377 (vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) || 378 (vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL)) { 379 #ifdef MSDOSFS_DEBUG 380 printf("msdosfs_setattr(): returning EINVAL\n"); 381 printf(" va_type %d, va_nlink %x, va_fsid %lx, va_fileid %lx\n", 382 vap->va_type, vap->va_nlink, vap->va_fsid, vap->va_fileid); 383 printf(" va_blocksize %lx, va_rdev %x, va_bytes %qx, va_gen %lx\n", 384 vap->va_blocksize, vap->va_rdev, vap->va_bytes, vap->va_gen); 385 printf(" va_uid %x, va_gid %x\n", 386 vap->va_uid, vap->va_gid); 387 #endif 388 return (EINVAL); 389 } 390 if (vap->va_flags != VNOVAL) { 391 if (vp->v_mount->mnt_flag & MNT_RDONLY) 392 return (EROFS); 393 if (cred->cr_uid != pmp->pm_uid && 394 (error = suser_xxx(cred, ap->a_p, PRISON_ROOT))) 395 return (error); 396 /* 397 * We are very inconsistent about handling unsupported 398 * attributes. We ignored the access time and the 399 * read and execute bits. We were strict for the other 400 * attributes. 401 * 402 * Here we are strict, stricter than ufs in not allowing 403 * users to attempt to set SF_SETTABLE bits or anyone to 404 * set unsupported bits. However, we ignore attempts to 405 * set ATTR_ARCHIVE for directories `cp -pr' from a more 406 * sensible file system attempts it a lot. 407 */ 408 if (cred->cr_uid != 0) { 409 if (vap->va_flags & SF_SETTABLE) 410 return EPERM; 411 } 412 if (vap->va_flags & ~SF_ARCHIVED) 413 return EOPNOTSUPP; 414 if (vap->va_flags & SF_ARCHIVED) 415 dep->de_Attributes &= ~ATTR_ARCHIVE; 416 else if (!(dep->de_Attributes & ATTR_DIRECTORY)) 417 dep->de_Attributes |= ATTR_ARCHIVE; 418 dep->de_flag |= DE_MODIFIED; 419 } 420 421 if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) { 422 uid_t uid; 423 gid_t gid; 424 425 if (vp->v_mount->mnt_flag & MNT_RDONLY) 426 return (EROFS); 427 uid = vap->va_uid; 428 if (uid == (uid_t)VNOVAL) 429 uid = pmp->pm_uid; 430 gid = vap->va_gid; 431 if (gid == (gid_t)VNOVAL) 432 gid = pmp->pm_gid; 433 if ((cred->cr_uid != pmp->pm_uid || uid != pmp->pm_uid || 434 (gid != pmp->pm_gid && !groupmember(gid, cred))) && 435 (error = suser_xxx(cred, ap->a_p, PRISON_ROOT))) 436 return error; 437 if (uid != pmp->pm_uid || gid != pmp->pm_gid) 438 return EINVAL; 439 } 440 441 if (vap->va_size != VNOVAL) { 442 /* 443 * Disallow write attempts on read-only file systems; 444 * unless the file is a socket, fifo, or a block or 445 * character device resident on the file system. 446 */ 447 switch (vp->v_type) { 448 case VDIR: 449 return (EISDIR); 450 /* NOT REACHED */ 451 case VLNK: 452 case VREG: 453 if (vp->v_mount->mnt_flag & MNT_RDONLY) 454 return (EROFS); 455 break; 456 default: 457 break; 458 } 459 error = detrunc(dep, vap->va_size, 0, cred, ap->a_p); 460 if (error) 461 return error; 462 } 463 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) { 464 if (vp->v_mount->mnt_flag & MNT_RDONLY) 465 return (EROFS); 466 if (cred->cr_uid != pmp->pm_uid && 467 (error = suser_xxx(cred, ap->a_p, PRISON_ROOT)) && 468 ((vap->va_vaflags & VA_UTIMES_NULL) == 0 || 469 (error = VOP_ACCESS(ap->a_vp, VWRITE, cred, ap->a_p)))) 470 return (error); 471 if (vp->v_type != VDIR) { 472 if ((pmp->pm_flags & MSDOSFSMNT_NOWIN95) == 0 && 473 vap->va_atime.tv_sec != VNOVAL) 474 unix2dostime(&vap->va_atime, &dep->de_ADate, NULL, NULL); 475 if (vap->va_mtime.tv_sec != VNOVAL) 476 unix2dostime(&vap->va_mtime, &dep->de_MDate, &dep->de_MTime, NULL); 477 dep->de_Attributes |= ATTR_ARCHIVE; 478 dep->de_flag |= DE_MODIFIED; 479 } 480 } 481 /* 482 * DOS files only have the ability to have their writability 483 * attribute set, so we use the owner write bit to set the readonly 484 * attribute. 485 */ 486 if (vap->va_mode != (mode_t)VNOVAL) { 487 if (vp->v_mount->mnt_flag & MNT_RDONLY) 488 return (EROFS); 489 if (cred->cr_uid != pmp->pm_uid && 490 (error = suser_xxx(cred, ap->a_p, PRISON_ROOT))) 491 return (error); 492 if (vp->v_type != VDIR) { 493 /* We ignore the read and execute bits. */ 494 if (vap->va_mode & VWRITE) 495 dep->de_Attributes &= ~ATTR_READONLY; 496 else 497 dep->de_Attributes |= ATTR_READONLY; 498 dep->de_flag |= DE_MODIFIED; 499 } 500 } 501 return (deupdat(dep, 1)); 502 } 503 504 static int 505 msdosfs_read(ap) 506 struct vop_read_args /* { 507 struct vnode *a_vp; 508 struct uio *a_uio; 509 int a_ioflag; 510 struct ucred *a_cred; 511 } */ *ap; 512 { 513 int error = 0; 514 int blsize; 515 int isadir; 516 int orig_resid; 517 u_int n; 518 u_long diff; 519 u_long on; 520 daddr_t lbn; 521 daddr_t rablock; 522 int rasize; 523 int seqcount; 524 struct buf *bp; 525 struct vnode *vp = ap->a_vp; 526 struct denode *dep = VTODE(vp); 527 struct msdosfsmount *pmp = dep->de_pmp; 528 struct uio *uio = ap->a_uio; 529 530 if (uio->uio_offset < 0) 531 return (EINVAL); 532 533 if ((uoff_t)uio->uio_offset > DOS_FILESIZE_MAX) 534 return (0); 535 /* 536 * If they didn't ask for any data, then we are done. 537 */ 538 orig_resid = uio->uio_resid; 539 if (orig_resid <= 0) 540 return (0); 541 542 seqcount = ap->a_ioflag >> 16; 543 544 isadir = dep->de_Attributes & ATTR_DIRECTORY; 545 do { 546 if (uio->uio_offset >= dep->de_FileSize) 547 break; 548 lbn = de_cluster(pmp, uio->uio_offset); 549 /* 550 * If we are operating on a directory file then be sure to 551 * do i/o with the vnode for the filesystem instead of the 552 * vnode for the directory. 553 */ 554 if (isadir) { 555 /* convert cluster # to block # */ 556 error = pcbmap(dep, lbn, &lbn, 0, &blsize); 557 if (error == E2BIG) { 558 error = EINVAL; 559 break; 560 } else if (error) 561 break; 562 error = bread(pmp->pm_devvp, lbn, blsize, NOCRED, &bp); 563 } else { 564 blsize = pmp->pm_bpcluster; 565 rablock = lbn + 1; 566 if (seqcount > 1 && 567 de_cn2off(pmp, rablock) < dep->de_FileSize) { 568 rasize = pmp->pm_bpcluster; 569 error = breadn(vp, lbn, blsize, 570 &rablock, &rasize, 1, NOCRED, &bp); 571 } else { 572 error = bread(vp, lbn, blsize, NOCRED, &bp); 573 } 574 } 575 if (error) { 576 brelse(bp); 577 break; 578 } 579 on = uio->uio_offset & pmp->pm_crbomask; 580 diff = pmp->pm_bpcluster - on; 581 n = diff > uio->uio_resid ? uio->uio_resid : diff; 582 diff = dep->de_FileSize - uio->uio_offset; 583 if (diff < n) 584 n = diff; 585 diff = blsize - bp->b_resid; 586 if (diff < n) 587 n = diff; 588 error = uiomove(bp->b_data + on, (int) n, uio); 589 brelse(bp); 590 } while (error == 0 && uio->uio_resid > 0 && n != 0); 591 if (!isadir && (error == 0 || uio->uio_resid != orig_resid) && 592 (vp->v_mount->mnt_flag & MNT_NOATIME) == 0) 593 dep->de_flag |= DE_ACCESS; 594 return (error); 595 } 596 597 /* 598 * Write data to a file or directory. 599 */ 600 static int 601 msdosfs_write(ap) 602 struct vop_write_args /* { 603 struct vnode *a_vp; 604 struct uio *a_uio; 605 int a_ioflag; 606 struct ucred *a_cred; 607 } */ *ap; 608 { 609 int n; 610 int croffset; 611 int resid; 612 u_long osize; 613 int error = 0; 614 u_long count; 615 daddr_t bn, lastcn; 616 struct buf *bp; 617 int ioflag = ap->a_ioflag; 618 struct uio *uio = ap->a_uio; 619 struct proc *p = uio->uio_procp; 620 struct vnode *vp = ap->a_vp; 621 struct vnode *thisvp; 622 struct denode *dep = VTODE(vp); 623 struct msdosfsmount *pmp = dep->de_pmp; 624 struct ucred *cred = ap->a_cred; 625 626 #ifdef MSDOSFS_DEBUG 627 printf("msdosfs_write(vp %p, uio %p, ioflag %x, cred %p\n", 628 vp, uio, ioflag, cred); 629 printf("msdosfs_write(): diroff %lu, dirclust %lu, startcluster %lu\n", 630 dep->de_diroffset, dep->de_dirclust, dep->de_StartCluster); 631 #endif 632 633 switch (vp->v_type) { 634 case VREG: 635 if (ioflag & IO_APPEND) 636 uio->uio_offset = dep->de_FileSize; 637 thisvp = vp; 638 break; 639 case VDIR: 640 return EISDIR; 641 default: 642 panic("msdosfs_write(): bad file type"); 643 } 644 645 if (uio->uio_offset < 0) 646 return (EFBIG); 647 648 if (uio->uio_resid == 0) 649 return (0); 650 651 /* 652 * If they've exceeded their filesize limit, tell them about it. 653 */ 654 if (p && 655 ((uoff_t)uio->uio_offset + uio->uio_resid > 656 p->p_rlimit[RLIMIT_FSIZE].rlim_cur)) { 657 PROC_LOCK(p); 658 psignal(p, SIGXFSZ); 659 PROC_UNLOCK(p); 660 return (EFBIG); 661 } 662 663 if ((uoff_t)uio->uio_offset + uio->uio_resid > DOS_FILESIZE_MAX) 664 return (EFBIG); 665 666 /* 667 * If the offset we are starting the write at is beyond the end of 668 * the file, then they've done a seek. Unix filesystems allow 669 * files with holes in them, DOS doesn't so we must fill the hole 670 * with zeroed blocks. 671 */ 672 if (uio->uio_offset > dep->de_FileSize) { 673 error = deextend(dep, uio->uio_offset, cred); 674 if (error) 675 return (error); 676 } 677 678 /* 679 * Remember some values in case the write fails. 680 */ 681 resid = uio->uio_resid; 682 osize = dep->de_FileSize; 683 684 /* 685 * If we write beyond the end of the file, extend it to its ultimate 686 * size ahead of the time to hopefully get a contiguous area. 687 */ 688 if (uio->uio_offset + resid > osize) { 689 count = de_clcount(pmp, uio->uio_offset + resid) - 690 de_clcount(pmp, osize); 691 error = extendfile(dep, count, NULL, NULL, 0); 692 if (error && (error != ENOSPC || (ioflag & IO_UNIT))) 693 goto errexit; 694 lastcn = dep->de_fc[FC_LASTFC].fc_frcn; 695 } else 696 lastcn = de_clcount(pmp, osize) - 1; 697 698 do { 699 if (de_cluster(pmp, uio->uio_offset) > lastcn) { 700 error = ENOSPC; 701 break; 702 } 703 704 croffset = uio->uio_offset & pmp->pm_crbomask; 705 n = min(uio->uio_resid, pmp->pm_bpcluster - croffset); 706 if (uio->uio_offset + n > dep->de_FileSize) { 707 dep->de_FileSize = uio->uio_offset + n; 708 /* The object size needs to be set before buffer is allocated */ 709 vnode_pager_setsize(vp, dep->de_FileSize); 710 } 711 712 bn = de_cluster(pmp, uio->uio_offset); 713 if ((uio->uio_offset & pmp->pm_crbomask) == 0 714 && (de_cluster(pmp, uio->uio_offset + uio->uio_resid) 715 > de_cluster(pmp, uio->uio_offset) 716 || uio->uio_offset + uio->uio_resid >= dep->de_FileSize)) { 717 /* 718 * If either the whole cluster gets written, 719 * or we write the cluster from its start beyond EOF, 720 * then no need to read data from disk. 721 */ 722 bp = getblk(thisvp, bn, pmp->pm_bpcluster, 0, 0); 723 clrbuf(bp); 724 /* 725 * Do the bmap now, since pcbmap needs buffers 726 * for the fat table. (see msdosfs_strategy) 727 */ 728 if (bp->b_blkno == bp->b_lblkno) { 729 error = pcbmap(dep, bp->b_lblkno, &bp->b_blkno, 730 0, 0); 731 if (error) 732 bp->b_blkno = -1; 733 } 734 if (bp->b_blkno == -1) { 735 brelse(bp); 736 if (!error) 737 error = EIO; /* XXX */ 738 break; 739 } 740 } else { 741 /* 742 * The block we need to write into exists, so read it in. 743 */ 744 error = bread(thisvp, bn, pmp->pm_bpcluster, cred, &bp); 745 if (error) { 746 brelse(bp); 747 break; 748 } 749 } 750 751 /* 752 * Should these vnode_pager_* functions be done on dir 753 * files? 754 */ 755 756 /* 757 * Copy the data from user space into the buf header. 758 */ 759 error = uiomove(bp->b_data + croffset, n, uio); 760 if (error) { 761 brelse(bp); 762 break; 763 } 764 765 /* 766 * If they want this synchronous then write it and wait for 767 * it. Otherwise, if on a cluster boundary write it 768 * asynchronously so we can move on to the next block 769 * without delay. Otherwise do a delayed write because we 770 * may want to write somemore into the block later. 771 */ 772 if (ioflag & IO_SYNC) 773 (void) bwrite(bp); 774 else if (n + croffset == pmp->pm_bpcluster) 775 bawrite(bp); 776 else 777 bdwrite(bp); 778 dep->de_flag |= DE_UPDATE; 779 } while (error == 0 && uio->uio_resid > 0); 780 781 /* 782 * If the write failed and they want us to, truncate the file back 783 * to the size it was before the write was attempted. 784 */ 785 errexit: 786 if (error) { 787 if (ioflag & IO_UNIT) { 788 detrunc(dep, osize, ioflag & IO_SYNC, NOCRED, NULL); 789 uio->uio_offset -= resid - uio->uio_resid; 790 uio->uio_resid = resid; 791 } else { 792 detrunc(dep, dep->de_FileSize, ioflag & IO_SYNC, NOCRED, NULL); 793 if (uio->uio_resid != resid) 794 error = 0; 795 } 796 } else if (ioflag & IO_SYNC) 797 error = deupdat(dep, 1); 798 return (error); 799 } 800 801 /* 802 * Flush the blocks of a file to disk. 803 * 804 * This function is worthless for vnodes that represent directories. Maybe we 805 * could just do a sync if they try an fsync on a directory file. 806 */ 807 static int 808 msdosfs_fsync(ap) 809 struct vop_fsync_args /* { 810 struct vnode *a_vp; 811 struct ucred *a_cred; 812 int a_waitfor; 813 struct proc *a_p; 814 } */ *ap; 815 { 816 struct vnode *vp = ap->a_vp; 817 int s; 818 struct buf *bp, *nbp; 819 820 /* 821 * Flush all dirty buffers associated with a vnode. 822 */ 823 loop: 824 s = splbio(); 825 for (bp = TAILQ_FIRST(&vp->v_dirtyblkhd); bp; bp = nbp) { 826 nbp = TAILQ_NEXT(bp, b_vnbufs); 827 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT)) 828 continue; 829 if ((bp->b_flags & B_DELWRI) == 0) 830 panic("msdosfs_fsync: not dirty"); 831 bremfree(bp); 832 splx(s); 833 (void) bwrite(bp); 834 goto loop; 835 } 836 while (vp->v_numoutput) { 837 vp->v_flag |= VBWAIT; 838 (void) tsleep((caddr_t)&vp->v_numoutput, PRIBIO + 1, "msdosfsn", 0); 839 } 840 #ifdef DIAGNOSTIC 841 if (!TAILQ_EMPTY(&vp->v_dirtyblkhd)) { 842 vprint("msdosfs_fsync: dirty", vp); 843 goto loop; 844 } 845 #endif 846 splx(s); 847 return (deupdat(VTODE(vp), ap->a_waitfor == MNT_WAIT)); 848 } 849 850 static int 851 msdosfs_remove(ap) 852 struct vop_remove_args /* { 853 struct vnode *a_dvp; 854 struct vnode *a_vp; 855 struct componentname *a_cnp; 856 } */ *ap; 857 { 858 struct denode *dep = VTODE(ap->a_vp); 859 struct denode *ddep = VTODE(ap->a_dvp); 860 int error; 861 862 if (ap->a_vp->v_type == VDIR) 863 error = EPERM; 864 else 865 error = removede(ddep, dep); 866 #ifdef MSDOSFS_DEBUG 867 printf("msdosfs_remove(), dep %p, v_usecount %d\n", dep, ap->a_vp->v_usecount); 868 #endif 869 return (error); 870 } 871 872 /* 873 * DOS filesystems don't know what links are. 874 */ 875 static int 876 msdosfs_link(ap) 877 struct vop_link_args /* { 878 struct vnode *a_tdvp; 879 struct vnode *a_vp; 880 struct componentname *a_cnp; 881 } */ *ap; 882 { 883 return (EOPNOTSUPP); 884 } 885 886 /* 887 * Renames on files require moving the denode to a new hash queue since the 888 * denode's location is used to compute which hash queue to put the file 889 * in. Unless it is a rename in place. For example "mv a b". 890 * 891 * What follows is the basic algorithm: 892 * 893 * if (file move) { 894 * if (dest file exists) { 895 * remove dest file 896 * } 897 * if (dest and src in same directory) { 898 * rewrite name in existing directory slot 899 * } else { 900 * write new entry in dest directory 901 * update offset and dirclust in denode 902 * move denode to new hash chain 903 * clear old directory entry 904 * } 905 * } else { 906 * directory move 907 * if (dest directory exists) { 908 * if (dest is not empty) { 909 * return ENOTEMPTY 910 * } 911 * remove dest directory 912 * } 913 * if (dest and src in same directory) { 914 * rewrite name in existing entry 915 * } else { 916 * be sure dest is not a child of src directory 917 * write entry in dest directory 918 * update "." and ".." in moved directory 919 * clear old directory entry for moved directory 920 * } 921 * } 922 * 923 * On entry: 924 * source's parent directory is unlocked 925 * source file or directory is unlocked 926 * destination's parent directory is locked 927 * destination file or directory is locked if it exists 928 * 929 * On exit: 930 * all denodes should be released 931 */ 932 static int 933 msdosfs_rename(ap) 934 struct vop_rename_args /* { 935 struct vnode *a_fdvp; 936 struct vnode *a_fvp; 937 struct componentname *a_fcnp; 938 struct vnode *a_tdvp; 939 struct vnode *a_tvp; 940 struct componentname *a_tcnp; 941 } */ *ap; 942 { 943 struct vnode *tdvp = ap->a_tdvp; 944 struct vnode *fvp = ap->a_fvp; 945 struct vnode *fdvp = ap->a_fdvp; 946 struct vnode *tvp = ap->a_tvp; 947 struct componentname *tcnp = ap->a_tcnp; 948 struct componentname *fcnp = ap->a_fcnp; 949 struct proc *p = fcnp->cn_proc; 950 struct denode *ip, *xp, *dp, *zp; 951 u_char toname[11], oldname[11]; 952 u_long from_diroffset, to_diroffset; 953 u_char to_count; 954 int doingdirectory = 0, newparent = 0; 955 int error; 956 u_long cn; 957 daddr_t bn; 958 struct denode *fddep; /* from file's parent directory */ 959 struct denode *fdep; /* from file or directory */ 960 struct denode *tddep; /* to file's parent directory */ 961 struct denode *tdep; /* to file or directory */ 962 struct msdosfsmount *pmp; 963 struct direntry *dotdotp; 964 struct buf *bp; 965 966 fddep = VTODE(ap->a_fdvp); 967 fdep = VTODE(ap->a_fvp); 968 tddep = VTODE(ap->a_tdvp); 969 tdep = tvp ? VTODE(tvp) : NULL; 970 pmp = fddep->de_pmp; 971 972 pmp = VFSTOMSDOSFS(fdvp->v_mount); 973 974 #ifdef DIAGNOSTIC 975 if ((tcnp->cn_flags & HASBUF) == 0 || 976 (fcnp->cn_flags & HASBUF) == 0) 977 panic("msdosfs_rename: no name"); 978 #endif 979 /* 980 * Check for cross-device rename. 981 */ 982 if ((fvp->v_mount != tdvp->v_mount) || 983 (tvp && (fvp->v_mount != tvp->v_mount))) { 984 error = EXDEV; 985 abortit: 986 if (tdvp == tvp) 987 vrele(tdvp); 988 else 989 vput(tdvp); 990 if (tvp) 991 vput(tvp); 992 vrele(fdvp); 993 vrele(fvp); 994 return (error); 995 } 996 997 /* 998 * If source and dest are the same, do nothing. 999 */ 1000 if (tvp == fvp) { 1001 error = 0; 1002 goto abortit; 1003 } 1004 1005 error = vn_lock(fvp, LK_EXCLUSIVE, p); 1006 if (error) 1007 goto abortit; 1008 dp = VTODE(fdvp); 1009 ip = VTODE(fvp); 1010 1011 /* 1012 * Be sure we are not renaming ".", "..", or an alias of ".". This 1013 * leads to a crippled directory tree. It's pretty tough to do a 1014 * "ls" or "pwd" with the "." directory entry missing, and "cd .." 1015 * doesn't work if the ".." entry is missing. 1016 */ 1017 if (ip->de_Attributes & ATTR_DIRECTORY) { 1018 /* 1019 * Avoid ".", "..", and aliases of "." for obvious reasons. 1020 */ 1021 if ((fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') || 1022 dp == ip || 1023 (fcnp->cn_flags & ISDOTDOT) || 1024 (tcnp->cn_flags & ISDOTDOT) || 1025 (ip->de_flag & DE_RENAME)) { 1026 VOP_UNLOCK(fvp, 0, p); 1027 error = EINVAL; 1028 goto abortit; 1029 } 1030 ip->de_flag |= DE_RENAME; 1031 doingdirectory++; 1032 } 1033 1034 /* 1035 * When the target exists, both the directory 1036 * and target vnodes are returned locked. 1037 */ 1038 dp = VTODE(tdvp); 1039 xp = tvp ? VTODE(tvp) : NULL; 1040 /* 1041 * Remember direntry place to use for destination 1042 */ 1043 to_diroffset = dp->de_fndoffset; 1044 to_count = dp->de_fndcnt; 1045 1046 /* 1047 * If ".." must be changed (ie the directory gets a new 1048 * parent) then the source directory must not be in the 1049 * directory heirarchy above the target, as this would 1050 * orphan everything below the source directory. Also 1051 * the user must have write permission in the source so 1052 * as to be able to change "..". We must repeat the call 1053 * to namei, as the parent directory is unlocked by the 1054 * call to doscheckpath(). 1055 */ 1056 error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred, tcnp->cn_proc); 1057 VOP_UNLOCK(fvp, 0, p); 1058 if (VTODE(fdvp)->de_StartCluster != VTODE(tdvp)->de_StartCluster) 1059 newparent = 1; 1060 if (doingdirectory && newparent) { 1061 if (error) /* write access check above */ 1062 goto bad; 1063 if (xp != NULL) 1064 vput(tvp); 1065 /* 1066 * doscheckpath() vput()'s dp, 1067 * so we have to do a relookup afterwards 1068 */ 1069 error = doscheckpath(ip, dp); 1070 if (error) 1071 goto out; 1072 if ((tcnp->cn_flags & SAVESTART) == 0) 1073 panic("msdosfs_rename: lost to startdir"); 1074 error = relookup(tdvp, &tvp, tcnp); 1075 if (error) 1076 goto out; 1077 dp = VTODE(tdvp); 1078 xp = tvp ? VTODE(tvp) : NULL; 1079 } 1080 1081 if (xp != NULL) { 1082 /* 1083 * Target must be empty if a directory and have no links 1084 * to it. Also, ensure source and target are compatible 1085 * (both directories, or both not directories). 1086 */ 1087 if (xp->de_Attributes & ATTR_DIRECTORY) { 1088 if (!dosdirempty(xp)) { 1089 error = ENOTEMPTY; 1090 goto bad; 1091 } 1092 if (!doingdirectory) { 1093 error = ENOTDIR; 1094 goto bad; 1095 } 1096 cache_purge(tdvp); 1097 } else if (doingdirectory) { 1098 error = EISDIR; 1099 goto bad; 1100 } 1101 error = removede(dp, xp); 1102 if (error) 1103 goto bad; 1104 vput(tvp); 1105 xp = NULL; 1106 } 1107 1108 /* 1109 * Convert the filename in tcnp into a dos filename. We copy this 1110 * into the denode and directory entry for the destination 1111 * file/directory. 1112 */ 1113 error = uniqdosname(VTODE(tdvp), tcnp, toname); 1114 if (error) 1115 goto abortit; 1116 1117 /* 1118 * Since from wasn't locked at various places above, 1119 * have to do a relookup here. 1120 */ 1121 fcnp->cn_flags &= ~MODMASK; 1122 fcnp->cn_flags |= LOCKPARENT | LOCKLEAF; 1123 if ((fcnp->cn_flags & SAVESTART) == 0) 1124 panic("msdosfs_rename: lost from startdir"); 1125 if (!newparent) 1126 VOP_UNLOCK(tdvp, 0, p); 1127 if (relookup(fdvp, &fvp, fcnp) == 0) 1128 vrele(fdvp); 1129 if (fvp == NULL) { 1130 /* 1131 * From name has disappeared. 1132 */ 1133 if (doingdirectory) 1134 panic("rename: lost dir entry"); 1135 vrele(ap->a_fvp); 1136 if (newparent) 1137 VOP_UNLOCK(tdvp, 0, p); 1138 vrele(tdvp); 1139 return 0; 1140 } 1141 xp = VTODE(fvp); 1142 zp = VTODE(fdvp); 1143 from_diroffset = zp->de_fndoffset; 1144 1145 /* 1146 * Ensure that the directory entry still exists and has not 1147 * changed till now. If the source is a file the entry may 1148 * have been unlinked or renamed. In either case there is 1149 * no further work to be done. If the source is a directory 1150 * then it cannot have been rmdir'ed or renamed; this is 1151 * prohibited by the DE_RENAME flag. 1152 */ 1153 if (xp != ip) { 1154 if (doingdirectory) 1155 panic("rename: lost dir entry"); 1156 vrele(ap->a_fvp); 1157 VOP_UNLOCK(fvp, 0, p); 1158 if (newparent) 1159 VOP_UNLOCK(fdvp, 0, p); 1160 xp = NULL; 1161 } else { 1162 vrele(fvp); 1163 xp = NULL; 1164 1165 /* 1166 * First write a new entry in the destination 1167 * directory and mark the entry in the source directory 1168 * as deleted. Then move the denode to the correct hash 1169 * chain for its new location in the filesystem. And, if 1170 * we moved a directory, then update its .. entry to point 1171 * to the new parent directory. 1172 */ 1173 bcopy(ip->de_Name, oldname, 11); 1174 bcopy(toname, ip->de_Name, 11); /* update denode */ 1175 dp->de_fndoffset = to_diroffset; 1176 dp->de_fndcnt = to_count; 1177 error = createde(ip, dp, (struct denode **)0, tcnp); 1178 if (error) { 1179 bcopy(oldname, ip->de_Name, 11); 1180 if (newparent) 1181 VOP_UNLOCK(fdvp, 0, p); 1182 VOP_UNLOCK(fvp, 0, p); 1183 goto bad; 1184 } 1185 ip->de_refcnt++; 1186 zp->de_fndoffset = from_diroffset; 1187 error = removede(zp, ip); 1188 if (error) { 1189 /* XXX should really panic here, fs is corrupt */ 1190 if (newparent) 1191 VOP_UNLOCK(fdvp, 0, p); 1192 VOP_UNLOCK(fvp, 0, p); 1193 goto bad; 1194 } 1195 if (!doingdirectory) { 1196 error = pcbmap(dp, de_cluster(pmp, to_diroffset), 0, 1197 &ip->de_dirclust, 0); 1198 if (error) { 1199 /* XXX should really panic here, fs is corrupt */ 1200 if (newparent) 1201 VOP_UNLOCK(fdvp, 0, p); 1202 VOP_UNLOCK(fvp, 0, p); 1203 goto bad; 1204 } 1205 if (ip->de_dirclust == MSDOSFSROOT) 1206 ip->de_diroffset = to_diroffset; 1207 else 1208 ip->de_diroffset = to_diroffset & pmp->pm_crbomask; 1209 } 1210 reinsert(ip); 1211 if (newparent) 1212 VOP_UNLOCK(fdvp, 0, p); 1213 } 1214 1215 /* 1216 * If we moved a directory to a new parent directory, then we must 1217 * fixup the ".." entry in the moved directory. 1218 */ 1219 if (doingdirectory && newparent) { 1220 cn = ip->de_StartCluster; 1221 if (cn == MSDOSFSROOT) { 1222 /* this should never happen */ 1223 panic("msdosfs_rename(): updating .. in root directory?"); 1224 } else 1225 bn = cntobn(pmp, cn); 1226 error = bread(pmp->pm_devvp, bn, pmp->pm_bpcluster, 1227 NOCRED, &bp); 1228 if (error) { 1229 /* XXX should really panic here, fs is corrupt */ 1230 brelse(bp); 1231 VOP_UNLOCK(fvp, 0, p); 1232 goto bad; 1233 } 1234 dotdotp = (struct direntry *)bp->b_data + 1; 1235 putushort(dotdotp->deStartCluster, dp->de_StartCluster); 1236 if (FAT32(pmp)) 1237 putushort(dotdotp->deHighClust, dp->de_StartCluster >> 16); 1238 error = bwrite(bp); 1239 if (error) { 1240 /* XXX should really panic here, fs is corrupt */ 1241 VOP_UNLOCK(fvp, 0, p); 1242 goto bad; 1243 } 1244 } 1245 1246 VOP_UNLOCK(fvp, 0, p); 1247 bad: 1248 if (xp) 1249 vput(tvp); 1250 vput(tdvp); 1251 out: 1252 ip->de_flag &= ~DE_RENAME; 1253 vrele(fdvp); 1254 vrele(fvp); 1255 return (error); 1256 1257 } 1258 1259 static struct { 1260 struct direntry dot; 1261 struct direntry dotdot; 1262 } dosdirtemplate = { 1263 { ". ", " ", /* the . entry */ 1264 ATTR_DIRECTORY, /* file attribute */ 1265 0, /* reserved */ 1266 0, { 0, 0 }, { 0, 0 }, /* create time & date */ 1267 { 0, 0 }, /* access date */ 1268 { 0, 0 }, /* high bits of start cluster */ 1269 { 210, 4 }, { 210, 4 }, /* modify time & date */ 1270 { 0, 0 }, /* startcluster */ 1271 { 0, 0, 0, 0 } /* filesize */ 1272 }, 1273 { ".. ", " ", /* the .. entry */ 1274 ATTR_DIRECTORY, /* file attribute */ 1275 0, /* reserved */ 1276 0, { 0, 0 }, { 0, 0 }, /* create time & date */ 1277 { 0, 0 }, /* access date */ 1278 { 0, 0 }, /* high bits of start cluster */ 1279 { 210, 4 }, { 210, 4 }, /* modify time & date */ 1280 { 0, 0 }, /* startcluster */ 1281 { 0, 0, 0, 0 } /* filesize */ 1282 } 1283 }; 1284 1285 static int 1286 msdosfs_mkdir(ap) 1287 struct vop_mkdir_args /* { 1288 struct vnode *a_dvp; 1289 struvt vnode **a_vpp; 1290 struvt componentname *a_cnp; 1291 struct vattr *a_vap; 1292 } */ *ap; 1293 { 1294 struct componentname *cnp = ap->a_cnp; 1295 struct denode *dep; 1296 struct denode *pdep = VTODE(ap->a_dvp); 1297 struct direntry *denp; 1298 struct msdosfsmount *pmp = pdep->de_pmp; 1299 struct buf *bp; 1300 u_long newcluster, pcl; 1301 int bn; 1302 int error; 1303 struct denode ndirent; 1304 struct timespec ts; 1305 1306 /* 1307 * If this is the root directory and there is no space left we 1308 * can't do anything. This is because the root directory can not 1309 * change size. 1310 */ 1311 if (pdep->de_StartCluster == MSDOSFSROOT 1312 && pdep->de_fndoffset >= pdep->de_FileSize) { 1313 error = ENOSPC; 1314 goto bad2; 1315 } 1316 1317 /* 1318 * Allocate a cluster to hold the about to be created directory. 1319 */ 1320 error = clusteralloc(pmp, 0, 1, CLUST_EOFE, &newcluster, NULL); 1321 if (error) 1322 goto bad2; 1323 1324 bzero(&ndirent, sizeof(ndirent)); 1325 ndirent.de_pmp = pmp; 1326 ndirent.de_flag = DE_ACCESS | DE_CREATE | DE_UPDATE; 1327 getnanotime(&ts); 1328 DETIMES(&ndirent, &ts, &ts, &ts); 1329 1330 /* 1331 * Now fill the cluster with the "." and ".." entries. And write 1332 * the cluster to disk. This way it is there for the parent 1333 * directory to be pointing at if there were a crash. 1334 */ 1335 bn = cntobn(pmp, newcluster); 1336 /* always succeeds */ 1337 bp = getblk(pmp->pm_devvp, bn, pmp->pm_bpcluster, 0, 0); 1338 bzero(bp->b_data, pmp->pm_bpcluster); 1339 bcopy(&dosdirtemplate, bp->b_data, sizeof dosdirtemplate); 1340 denp = (struct direntry *)bp->b_data; 1341 putushort(denp[0].deStartCluster, newcluster); 1342 putushort(denp[0].deCDate, ndirent.de_CDate); 1343 putushort(denp[0].deCTime, ndirent.de_CTime); 1344 denp[0].deCHundredth = ndirent.de_CHun; 1345 putushort(denp[0].deADate, ndirent.de_ADate); 1346 putushort(denp[0].deMDate, ndirent.de_MDate); 1347 putushort(denp[0].deMTime, ndirent.de_MTime); 1348 pcl = pdep->de_StartCluster; 1349 if (FAT32(pmp) && pcl == pmp->pm_rootdirblk) 1350 pcl = 0; 1351 putushort(denp[1].deStartCluster, pcl); 1352 putushort(denp[1].deCDate, ndirent.de_CDate); 1353 putushort(denp[1].deCTime, ndirent.de_CTime); 1354 denp[1].deCHundredth = ndirent.de_CHun; 1355 putushort(denp[1].deADate, ndirent.de_ADate); 1356 putushort(denp[1].deMDate, ndirent.de_MDate); 1357 putushort(denp[1].deMTime, ndirent.de_MTime); 1358 if (FAT32(pmp)) { 1359 putushort(denp[0].deHighClust, newcluster >> 16); 1360 putushort(denp[1].deHighClust, pdep->de_StartCluster >> 16); 1361 } 1362 1363 error = bwrite(bp); 1364 if (error) 1365 goto bad; 1366 1367 /* 1368 * Now build up a directory entry pointing to the newly allocated 1369 * cluster. This will be written to an empty slot in the parent 1370 * directory. 1371 */ 1372 #ifdef DIAGNOSTIC 1373 if ((cnp->cn_flags & HASBUF) == 0) 1374 panic("msdosfs_mkdir: no name"); 1375 #endif 1376 error = uniqdosname(pdep, cnp, ndirent.de_Name); 1377 if (error) 1378 goto bad; 1379 1380 ndirent.de_Attributes = ATTR_DIRECTORY; 1381 ndirent.de_LowerCase = 0; 1382 ndirent.de_StartCluster = newcluster; 1383 ndirent.de_FileSize = 0; 1384 ndirent.de_dev = pdep->de_dev; 1385 ndirent.de_devvp = pdep->de_devvp; 1386 error = createde(&ndirent, pdep, &dep, cnp); 1387 if (error) 1388 goto bad; 1389 *ap->a_vpp = DETOV(dep); 1390 return (0); 1391 1392 bad: 1393 clusterfree(pmp, newcluster, NULL); 1394 bad2: 1395 return (error); 1396 } 1397 1398 static int 1399 msdosfs_rmdir(ap) 1400 struct vop_rmdir_args /* { 1401 struct vnode *a_dvp; 1402 struct vnode *a_vp; 1403 struct componentname *a_cnp; 1404 } */ *ap; 1405 { 1406 register struct vnode *vp = ap->a_vp; 1407 register struct vnode *dvp = ap->a_dvp; 1408 register struct componentname *cnp = ap->a_cnp; 1409 register struct denode *ip, *dp; 1410 struct proc *p = cnp->cn_proc; 1411 int error; 1412 1413 ip = VTODE(vp); 1414 dp = VTODE(dvp); 1415 1416 /* 1417 * Verify the directory is empty (and valid). 1418 * (Rmdir ".." won't be valid since 1419 * ".." will contain a reference to 1420 * the current directory and thus be 1421 * non-empty.) 1422 */ 1423 error = 0; 1424 if (!dosdirempty(ip) || ip->de_flag & DE_RENAME) { 1425 error = ENOTEMPTY; 1426 goto out; 1427 } 1428 /* 1429 * Delete the entry from the directory. For dos filesystems this 1430 * gets rid of the directory entry on disk, the in memory copy 1431 * still exists but the de_refcnt is <= 0. This prevents it from 1432 * being found by deget(). When the vput() on dep is done we give 1433 * up access and eventually msdosfs_reclaim() will be called which 1434 * will remove it from the denode cache. 1435 */ 1436 error = removede(dp, ip); 1437 if (error) 1438 goto out; 1439 /* 1440 * This is where we decrement the link count in the parent 1441 * directory. Since dos filesystems don't do this we just purge 1442 * the name cache. 1443 */ 1444 cache_purge(dvp); 1445 VOP_UNLOCK(dvp, 0, p); 1446 /* 1447 * Truncate the directory that is being deleted. 1448 */ 1449 error = detrunc(ip, (u_long)0, IO_SYNC, cnp->cn_cred, p); 1450 cache_purge(vp); 1451 1452 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY, p); 1453 out: 1454 return (error); 1455 } 1456 1457 /* 1458 * DOS filesystems don't know what symlinks are. 1459 */ 1460 static int 1461 msdosfs_symlink(ap) 1462 struct vop_symlink_args /* { 1463 struct vnode *a_dvp; 1464 struct vnode **a_vpp; 1465 struct componentname *a_cnp; 1466 struct vattr *a_vap; 1467 char *a_target; 1468 } */ *ap; 1469 { 1470 return (EOPNOTSUPP); 1471 } 1472 1473 static int 1474 msdosfs_readdir(ap) 1475 struct vop_readdir_args /* { 1476 struct vnode *a_vp; 1477 struct uio *a_uio; 1478 struct ucred *a_cred; 1479 int *a_eofflag; 1480 int *a_ncookies; 1481 u_long **a_cookies; 1482 } */ *ap; 1483 { 1484 int error = 0; 1485 int diff; 1486 long n; 1487 int blsize; 1488 long on; 1489 u_long cn; 1490 u_long fileno; 1491 u_long dirsperblk; 1492 long bias = 0; 1493 daddr_t bn, lbn; 1494 struct buf *bp; 1495 struct denode *dep = VTODE(ap->a_vp); 1496 struct msdosfsmount *pmp = dep->de_pmp; 1497 struct direntry *dentp; 1498 struct dirent dirbuf; 1499 struct uio *uio = ap->a_uio; 1500 u_long *cookies = NULL; 1501 int ncookies = 0; 1502 off_t offset, off; 1503 int chksum = -1; 1504 1505 #ifdef MSDOSFS_DEBUG 1506 printf("msdosfs_readdir(): vp %p, uio %p, cred %p, eofflagp %p\n", 1507 ap->a_vp, uio, ap->a_cred, ap->a_eofflag); 1508 #endif 1509 1510 /* 1511 * msdosfs_readdir() won't operate properly on regular files since 1512 * it does i/o only with the the filesystem vnode, and hence can 1513 * retrieve the wrong block from the buffer cache for a plain file. 1514 * So, fail attempts to readdir() on a plain file. 1515 */ 1516 if ((dep->de_Attributes & ATTR_DIRECTORY) == 0) 1517 return (ENOTDIR); 1518 1519 /* 1520 * To be safe, initialize dirbuf 1521 */ 1522 bzero(dirbuf.d_name, sizeof(dirbuf.d_name)); 1523 1524 /* 1525 * If the user buffer is smaller than the size of one dos directory 1526 * entry or the file offset is not a multiple of the size of a 1527 * directory entry, then we fail the read. 1528 */ 1529 off = offset = uio->uio_offset; 1530 if (uio->uio_resid < sizeof(struct direntry) || 1531 (offset & (sizeof(struct direntry) - 1))) 1532 return (EINVAL); 1533 1534 if (ap->a_ncookies) { 1535 ncookies = uio->uio_resid / 16; 1536 MALLOC(cookies, u_long *, ncookies * sizeof(u_long), M_TEMP, 1537 M_WAITOK); 1538 *ap->a_cookies = cookies; 1539 *ap->a_ncookies = ncookies; 1540 } 1541 1542 dirsperblk = pmp->pm_BytesPerSec / sizeof(struct direntry); 1543 1544 /* 1545 * If they are reading from the root directory then, we simulate 1546 * the . and .. entries since these don't exist in the root 1547 * directory. We also set the offset bias to make up for having to 1548 * simulate these entries. By this I mean that at file offset 64 we 1549 * read the first entry in the root directory that lives on disk. 1550 */ 1551 if (dep->de_StartCluster == MSDOSFSROOT 1552 || (FAT32(pmp) && dep->de_StartCluster == pmp->pm_rootdirblk)) { 1553 #if 0 1554 printf("msdosfs_readdir(): going after . or .. in root dir, offset %d\n", 1555 offset); 1556 #endif 1557 bias = 2 * sizeof(struct direntry); 1558 if (offset < bias) { 1559 for (n = (int)offset / sizeof(struct direntry); 1560 n < 2; n++) { 1561 if (FAT32(pmp)) 1562 dirbuf.d_fileno = cntobn(pmp, 1563 pmp->pm_rootdirblk) 1564 * dirsperblk; 1565 else 1566 dirbuf.d_fileno = 1; 1567 dirbuf.d_type = DT_DIR; 1568 switch (n) { 1569 case 0: 1570 dirbuf.d_namlen = 1; 1571 strcpy(dirbuf.d_name, "."); 1572 break; 1573 case 1: 1574 dirbuf.d_namlen = 2; 1575 strcpy(dirbuf.d_name, ".."); 1576 break; 1577 } 1578 dirbuf.d_reclen = GENERIC_DIRSIZ(&dirbuf); 1579 if (uio->uio_resid < dirbuf.d_reclen) 1580 goto out; 1581 error = uiomove((caddr_t) &dirbuf, 1582 dirbuf.d_reclen, uio); 1583 if (error) 1584 goto out; 1585 offset += sizeof(struct direntry); 1586 off = offset; 1587 if (cookies) { 1588 *cookies++ = offset; 1589 if (--ncookies <= 0) 1590 goto out; 1591 } 1592 } 1593 } 1594 } 1595 1596 off = offset; 1597 while (uio->uio_resid > 0) { 1598 lbn = de_cluster(pmp, offset - bias); 1599 on = (offset - bias) & pmp->pm_crbomask; 1600 n = min(pmp->pm_bpcluster - on, uio->uio_resid); 1601 diff = dep->de_FileSize - (offset - bias); 1602 if (diff <= 0) 1603 break; 1604 n = min(n, diff); 1605 error = pcbmap(dep, lbn, &bn, &cn, &blsize); 1606 if (error) 1607 break; 1608 error = bread(pmp->pm_devvp, bn, blsize, NOCRED, &bp); 1609 if (error) { 1610 brelse(bp); 1611 return (error); 1612 } 1613 n = min(n, blsize - bp->b_resid); 1614 1615 /* 1616 * Convert from dos directory entries to fs-independent 1617 * directory entries. 1618 */ 1619 for (dentp = (struct direntry *)(bp->b_data + on); 1620 (char *)dentp < bp->b_data + on + n; 1621 dentp++, offset += sizeof(struct direntry)) { 1622 #if 0 1623 printf("rd: dentp %08x prev %08x crnt %08x deName %02x attr %02x\n", 1624 dentp, prev, crnt, dentp->deName[0], dentp->deAttributes); 1625 #endif 1626 /* 1627 * If this is an unused entry, we can stop. 1628 */ 1629 if (dentp->deName[0] == SLOT_EMPTY) { 1630 brelse(bp); 1631 goto out; 1632 } 1633 /* 1634 * Skip deleted entries. 1635 */ 1636 if (dentp->deName[0] == SLOT_DELETED) { 1637 chksum = -1; 1638 continue; 1639 } 1640 1641 /* 1642 * Handle Win95 long directory entries 1643 */ 1644 if (dentp->deAttributes == ATTR_WIN95) { 1645 if (pmp->pm_flags & MSDOSFSMNT_SHORTNAME) 1646 continue; 1647 chksum = win2unixfn((struct winentry *)dentp, 1648 &dirbuf, chksum, 1649 pmp->pm_flags & MSDOSFSMNT_U2WTABLE, 1650 pmp->pm_u2w); 1651 continue; 1652 } 1653 1654 /* 1655 * Skip volume labels 1656 */ 1657 if (dentp->deAttributes & ATTR_VOLUME) { 1658 chksum = -1; 1659 continue; 1660 } 1661 /* 1662 * This computation of d_fileno must match 1663 * the computation of va_fileid in 1664 * msdosfs_getattr. 1665 */ 1666 if (dentp->deAttributes & ATTR_DIRECTORY) { 1667 fileno = getushort(dentp->deStartCluster); 1668 if (FAT32(pmp)) 1669 fileno |= getushort(dentp->deHighClust) << 16; 1670 /* if this is the root directory */ 1671 if (fileno == MSDOSFSROOT) 1672 if (FAT32(pmp)) 1673 fileno = cntobn(pmp, 1674 pmp->pm_rootdirblk) 1675 * dirsperblk; 1676 else 1677 fileno = 1; 1678 else 1679 fileno = cntobn(pmp, fileno) * dirsperblk; 1680 dirbuf.d_fileno = fileno; 1681 dirbuf.d_type = DT_DIR; 1682 } else { 1683 dirbuf.d_fileno = offset / sizeof(struct direntry); 1684 dirbuf.d_type = DT_REG; 1685 } 1686 if (chksum != winChksum(dentp->deName)) 1687 dirbuf.d_namlen = dos2unixfn(dentp->deName, 1688 (u_char *)dirbuf.d_name, 1689 dentp->deLowerCase | 1690 ((pmp->pm_flags & MSDOSFSMNT_SHORTNAME) ? 1691 (LCASE_BASE | LCASE_EXT) : 0), 1692 pmp->pm_flags & MSDOSFSMNT_U2WTABLE, 1693 pmp->pm_d2u, 1694 pmp->pm_flags & MSDOSFSMNT_ULTABLE, 1695 pmp->pm_ul); 1696 else 1697 dirbuf.d_name[dirbuf.d_namlen] = 0; 1698 chksum = -1; 1699 dirbuf.d_reclen = GENERIC_DIRSIZ(&dirbuf); 1700 if (uio->uio_resid < dirbuf.d_reclen) { 1701 brelse(bp); 1702 goto out; 1703 } 1704 error = uiomove((caddr_t) &dirbuf, 1705 dirbuf.d_reclen, uio); 1706 if (error) { 1707 brelse(bp); 1708 goto out; 1709 } 1710 if (cookies) { 1711 *cookies++ = offset + sizeof(struct direntry); 1712 if (--ncookies <= 0) { 1713 brelse(bp); 1714 goto out; 1715 } 1716 } 1717 off = offset + sizeof(struct direntry); 1718 } 1719 brelse(bp); 1720 } 1721 out: 1722 /* Subtract unused cookies */ 1723 if (ap->a_ncookies) 1724 *ap->a_ncookies -= ncookies; 1725 1726 uio->uio_offset = off; 1727 1728 /* 1729 * Set the eofflag (NFS uses it) 1730 */ 1731 if (ap->a_eofflag) { 1732 if (dep->de_FileSize - (offset - bias) <= 0) 1733 *ap->a_eofflag = 1; 1734 else 1735 *ap->a_eofflag = 0; 1736 } 1737 return (error); 1738 } 1739 1740 /* 1741 * vp - address of vnode file the file 1742 * bn - which cluster we are interested in mapping to a filesystem block number. 1743 * vpp - returns the vnode for the block special file holding the filesystem 1744 * containing the file of interest 1745 * bnp - address of where to return the filesystem relative block number 1746 */ 1747 static int 1748 msdosfs_bmap(ap) 1749 struct vop_bmap_args /* { 1750 struct vnode *a_vp; 1751 daddr_t a_bn; 1752 struct vnode **a_vpp; 1753 daddr_t *a_bnp; 1754 int *a_runp; 1755 int *a_runb; 1756 } */ *ap; 1757 { 1758 struct denode *dep = VTODE(ap->a_vp); 1759 1760 if (ap->a_vpp != NULL) 1761 *ap->a_vpp = dep->de_devvp; 1762 if (ap->a_bnp == NULL) 1763 return (0); 1764 if (ap->a_runp) { 1765 /* 1766 * Sequential clusters should be counted here. 1767 */ 1768 *ap->a_runp = 0; 1769 } 1770 if (ap->a_runb) { 1771 *ap->a_runb = 0; 1772 } 1773 return (pcbmap(dep, ap->a_bn, ap->a_bnp, 0, 0)); 1774 } 1775 1776 static int 1777 msdosfs_strategy(ap) 1778 struct vop_strategy_args /* { 1779 struct vnode *a_vp; 1780 struct buf *a_bp; 1781 } */ *ap; 1782 { 1783 struct buf *bp = ap->a_bp; 1784 struct denode *dep = VTODE(bp->b_vp); 1785 struct vnode *vp; 1786 int error = 0; 1787 1788 if (bp->b_vp->v_type == VBLK || bp->b_vp->v_type == VCHR) 1789 panic("msdosfs_strategy: spec"); 1790 /* 1791 * If we don't already know the filesystem relative block number 1792 * then get it using pcbmap(). If pcbmap() returns the block 1793 * number as -1 then we've got a hole in the file. DOS filesystems 1794 * don't allow files with holes, so we shouldn't ever see this. 1795 */ 1796 if (bp->b_blkno == bp->b_lblkno) { 1797 error = pcbmap(dep, bp->b_lblkno, &bp->b_blkno, 0, 0); 1798 if (error) { 1799 bp->b_error = error; 1800 bp->b_ioflags |= BIO_ERROR; 1801 bufdone(bp); 1802 return (error); 1803 } 1804 if ((long)bp->b_blkno == -1) 1805 vfs_bio_clrbuf(bp); 1806 } 1807 if (bp->b_blkno == -1) { 1808 bufdone(bp); 1809 return (0); 1810 } 1811 /* 1812 * Read/write the block from/to the disk that contains the desired 1813 * file block. 1814 */ 1815 vp = dep->de_devvp; 1816 bp->b_dev = vp->v_rdev; 1817 VOP_STRATEGY(vp, bp); 1818 return (0); 1819 } 1820 1821 static int 1822 msdosfs_print(ap) 1823 struct vop_print_args /* { 1824 struct vnode *vp; 1825 } */ *ap; 1826 { 1827 struct denode *dep = VTODE(ap->a_vp); 1828 1829 printf( 1830 "tag VT_MSDOSFS, startcluster %lu, dircluster %lu, diroffset %lu ", 1831 dep->de_StartCluster, dep->de_dirclust, dep->de_diroffset); 1832 printf(" dev %d, %d", major(dep->de_dev), minor(dep->de_dev)); 1833 lockmgr_printinfo(&ap->a_vp->v_lock); 1834 printf("\n"); 1835 return (0); 1836 } 1837 1838 static int 1839 msdosfs_pathconf(ap) 1840 struct vop_pathconf_args /* { 1841 struct vnode *a_vp; 1842 int a_name; 1843 int *a_retval; 1844 } */ *ap; 1845 { 1846 struct msdosfsmount *pmp = VTODE(ap->a_vp)->de_pmp; 1847 1848 switch (ap->a_name) { 1849 case _PC_LINK_MAX: 1850 *ap->a_retval = 1; 1851 return (0); 1852 case _PC_NAME_MAX: 1853 *ap->a_retval = pmp->pm_flags & MSDOSFSMNT_LONGNAME ? WIN_MAXLEN : 12; 1854 return (0); 1855 case _PC_PATH_MAX: 1856 *ap->a_retval = PATH_MAX; 1857 return (0); 1858 case _PC_CHOWN_RESTRICTED: 1859 *ap->a_retval = 1; 1860 return (0); 1861 case _PC_NO_TRUNC: 1862 *ap->a_retval = 0; 1863 return (0); 1864 default: 1865 return (EINVAL); 1866 } 1867 /* NOTREACHED */ 1868 } 1869 1870 /* 1871 * get page routine 1872 * 1873 * XXX By default, wimp out... note that a_offset is ignored (and always 1874 * XXX has been). 1875 */ 1876 int 1877 msdosfs_getpages(ap) 1878 struct vop_getpages_args *ap; 1879 { 1880 return vnode_pager_generic_getpages(ap->a_vp, ap->a_m, ap->a_count, 1881 ap->a_reqpage); 1882 } 1883 1884 /* 1885 * put page routine 1886 * 1887 * XXX By default, wimp out... note that a_offset is ignored (and always 1888 * XXX has been). 1889 */ 1890 int 1891 msdosfs_putpages(ap) 1892 struct vop_putpages_args *ap; 1893 { 1894 return vnode_pager_generic_putpages(ap->a_vp, ap->a_m, ap->a_count, 1895 ap->a_sync, ap->a_rtvals); 1896 } 1897 1898 /* Global vfs data structures for msdosfs */ 1899 vop_t **msdosfs_vnodeop_p; 1900 static struct vnodeopv_entry_desc msdosfs_vnodeop_entries[] = { 1901 { &vop_default_desc, (vop_t *) vop_defaultop }, 1902 { &vop_access_desc, (vop_t *) msdosfs_access }, 1903 { &vop_bmap_desc, (vop_t *) msdosfs_bmap }, 1904 { &vop_cachedlookup_desc, (vop_t *) msdosfs_lookup }, 1905 { &vop_close_desc, (vop_t *) msdosfs_close }, 1906 { &vop_create_desc, (vop_t *) msdosfs_create }, 1907 { &vop_fsync_desc, (vop_t *) msdosfs_fsync }, 1908 { &vop_getattr_desc, (vop_t *) msdosfs_getattr }, 1909 { &vop_inactive_desc, (vop_t *) msdosfs_inactive }, 1910 { &vop_islocked_desc, (vop_t *) vop_stdislocked }, 1911 { &vop_link_desc, (vop_t *) msdosfs_link }, 1912 { &vop_lock_desc, (vop_t *) vop_stdlock }, 1913 { &vop_lookup_desc, (vop_t *) vfs_cache_lookup }, 1914 { &vop_mkdir_desc, (vop_t *) msdosfs_mkdir }, 1915 { &vop_mknod_desc, (vop_t *) msdosfs_mknod }, 1916 { &vop_pathconf_desc, (vop_t *) msdosfs_pathconf }, 1917 { &vop_print_desc, (vop_t *) msdosfs_print }, 1918 { &vop_read_desc, (vop_t *) msdosfs_read }, 1919 { &vop_readdir_desc, (vop_t *) msdosfs_readdir }, 1920 { &vop_reclaim_desc, (vop_t *) msdosfs_reclaim }, 1921 { &vop_remove_desc, (vop_t *) msdosfs_remove }, 1922 { &vop_rename_desc, (vop_t *) msdosfs_rename }, 1923 { &vop_rmdir_desc, (vop_t *) msdosfs_rmdir }, 1924 { &vop_setattr_desc, (vop_t *) msdosfs_setattr }, 1925 { &vop_strategy_desc, (vop_t *) msdosfs_strategy }, 1926 { &vop_symlink_desc, (vop_t *) msdosfs_symlink }, 1927 { &vop_unlock_desc, (vop_t *) vop_stdunlock }, 1928 { &vop_write_desc, (vop_t *) msdosfs_write }, 1929 { &vop_getpages_desc, (vop_t *) msdosfs_getpages }, 1930 { &vop_putpages_desc, (vop_t *) msdosfs_putpages }, 1931 { NULL, NULL } 1932 }; 1933 static struct vnodeopv_desc msdosfs_vnodeop_opv_desc = 1934 { &msdosfs_vnodeop_p, msdosfs_vnodeop_entries }; 1935 1936 VNODEOP_SET(msdosfs_vnodeop_opv_desc); 1937