1 /*- 2 * modified for EXT2FS support in Lites 1.1 3 * 4 * Aug 1995, Godmar Back (gback@cs.utah.edu) 5 * University of Utah, Department of Computer Science 6 */ 7 /*- 8 * Copyright (c) 1982, 1986, 1989, 1993 9 * The Regents of the University of California. All rights reserved. 10 * (c) UNIX System Laboratories, Inc. 11 * All or some portions of this file are derived from material licensed 12 * to the University of California by American Telephone and Telegraph 13 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 14 * the permission of UNIX System Laboratories, Inc. 15 * 16 * Redistribution and use in source and binary forms, with or without 17 * modification, are permitted provided that the following conditions 18 * are met: 19 * 1. Redistributions of source code must retain the above copyright 20 * notice, this list of conditions and the following disclaimer. 21 * 2. Redistributions in binary form must reproduce the above copyright 22 * notice, this list of conditions and the following disclaimer in the 23 * documentation and/or other materials provided with the distribution. 24 * 3. Neither the name of the University nor the names of its contributors 25 * may be used to endorse or promote products derived from this software 26 * without specific prior written permission. 27 * 28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 38 * SUCH DAMAGE. 39 * 40 * @(#)ufs_vnops.c 8.7 (Berkeley) 2/3/94 41 * @(#)ufs_vnops.c 8.27 (Berkeley) 5/27/95 42 * $FreeBSD$ 43 */ 44 45 #include "opt_suiddir.h" 46 47 #include <sys/param.h> 48 #include <sys/systm.h> 49 #include <sys/kernel.h> 50 #include <sys/fcntl.h> 51 #include <sys/filio.h> 52 #include <sys/stat.h> 53 #include <sys/bio.h> 54 #include <sys/buf.h> 55 #include <sys/endian.h> 56 #include <sys/priv.h> 57 #include <sys/rwlock.h> 58 #include <sys/mount.h> 59 #include <sys/unistd.h> 60 #include <sys/time.h> 61 #include <sys/vnode.h> 62 #include <sys/namei.h> 63 #include <sys/lockf.h> 64 #include <sys/event.h> 65 #include <sys/conf.h> 66 #include <sys/file.h> 67 68 #include <vm/vm.h> 69 #include <vm/vm_param.h> 70 #include <vm/vm_extern.h> 71 #include <vm/vm_object.h> 72 #include <vm/vm_page.h> 73 #include <vm/vm_pager.h> 74 #include <vm/vnode_pager.h> 75 76 #include "opt_directio.h" 77 78 #include <ufs/ufs/dir.h> 79 80 #include <fs/ext2fs/fs.h> 81 #include <fs/ext2fs/inode.h> 82 #include <fs/ext2fs/ext2_extern.h> 83 #include <fs/ext2fs/ext2fs.h> 84 #include <fs/ext2fs/ext2_dinode.h> 85 #include <fs/ext2fs/ext2_dir.h> 86 #include <fs/ext2fs/ext2_mount.h> 87 88 static int ext2_makeinode(int mode, struct vnode *, struct vnode **, struct componentname *); 89 static void ext2_itimes_locked(struct vnode *); 90 static int ext4_ext_read(struct vop_read_args *); 91 static int ext2_ind_read(struct vop_read_args *); 92 93 static vop_access_t ext2_access; 94 static int ext2_chmod(struct vnode *, int, struct ucred *, struct thread *); 95 static int ext2_chown(struct vnode *, uid_t, gid_t, struct ucred *, 96 struct thread *); 97 static vop_close_t ext2_close; 98 static vop_create_t ext2_create; 99 static vop_fsync_t ext2_fsync; 100 static vop_getattr_t ext2_getattr; 101 static vop_ioctl_t ext2_ioctl; 102 static vop_link_t ext2_link; 103 static vop_mkdir_t ext2_mkdir; 104 static vop_mknod_t ext2_mknod; 105 static vop_open_t ext2_open; 106 static vop_pathconf_t ext2_pathconf; 107 static vop_print_t ext2_print; 108 static vop_read_t ext2_read; 109 static vop_readlink_t ext2_readlink; 110 static vop_remove_t ext2_remove; 111 static vop_rename_t ext2_rename; 112 static vop_rmdir_t ext2_rmdir; 113 static vop_setattr_t ext2_setattr; 114 static vop_strategy_t ext2_strategy; 115 static vop_symlink_t ext2_symlink; 116 static vop_write_t ext2_write; 117 static vop_vptofh_t ext2_vptofh; 118 static vop_close_t ext2fifo_close; 119 static vop_kqfilter_t ext2fifo_kqfilter; 120 121 /* Global vfs data structures for ext2. */ 122 struct vop_vector ext2_vnodeops = { 123 .vop_default = &default_vnodeops, 124 .vop_access = ext2_access, 125 .vop_bmap = ext2_bmap, 126 .vop_cachedlookup = ext2_lookup, 127 .vop_close = ext2_close, 128 .vop_create = ext2_create, 129 .vop_fsync = ext2_fsync, 130 .vop_getpages = vnode_pager_local_getpages, 131 .vop_getpages_async = vnode_pager_local_getpages_async, 132 .vop_getattr = ext2_getattr, 133 .vop_inactive = ext2_inactive, 134 .vop_ioctl = ext2_ioctl, 135 .vop_link = ext2_link, 136 .vop_lookup = vfs_cache_lookup, 137 .vop_mkdir = ext2_mkdir, 138 .vop_mknod = ext2_mknod, 139 .vop_open = ext2_open, 140 .vop_pathconf = ext2_pathconf, 141 .vop_poll = vop_stdpoll, 142 .vop_print = ext2_print, 143 .vop_read = ext2_read, 144 .vop_readdir = ext2_readdir, 145 .vop_readlink = ext2_readlink, 146 .vop_reallocblks = ext2_reallocblks, 147 .vop_reclaim = ext2_reclaim, 148 .vop_remove = ext2_remove, 149 .vop_rename = ext2_rename, 150 .vop_rmdir = ext2_rmdir, 151 .vop_setattr = ext2_setattr, 152 .vop_strategy = ext2_strategy, 153 .vop_symlink = ext2_symlink, 154 .vop_write = ext2_write, 155 .vop_vptofh = ext2_vptofh, 156 }; 157 158 struct vop_vector ext2_fifoops = { 159 .vop_default = &fifo_specops, 160 .vop_access = ext2_access, 161 .vop_close = ext2fifo_close, 162 .vop_fsync = ext2_fsync, 163 .vop_getattr = ext2_getattr, 164 .vop_inactive = ext2_inactive, 165 .vop_kqfilter = ext2fifo_kqfilter, 166 .vop_print = ext2_print, 167 .vop_read = VOP_PANIC, 168 .vop_reclaim = ext2_reclaim, 169 .vop_setattr = ext2_setattr, 170 .vop_write = VOP_PANIC, 171 .vop_vptofh = ext2_vptofh, 172 }; 173 174 /* 175 * A virgin directory (no blushing please). 176 * Note that the type and namlen fields are reversed relative to ext2. 177 * Also, we don't use `struct odirtemplate', since it would just cause 178 * endianness problems. 179 */ 180 static struct dirtemplate mastertemplate = { 181 0, 12, 1, EXT2_FT_DIR, ".", 182 0, DIRBLKSIZ - 12, 2, EXT2_FT_DIR, ".." 183 }; 184 static struct dirtemplate omastertemplate = { 185 0, 12, 1, EXT2_FT_UNKNOWN, ".", 186 0, DIRBLKSIZ - 12, 2, EXT2_FT_UNKNOWN, ".." 187 }; 188 189 static void 190 ext2_itimes_locked(struct vnode *vp) 191 { 192 struct inode *ip; 193 struct timespec ts; 194 195 ASSERT_VI_LOCKED(vp, __func__); 196 197 ip = VTOI(vp); 198 if ((ip->i_flag & (IN_ACCESS | IN_CHANGE | IN_UPDATE)) == 0) 199 return; 200 if ((vp->v_type == VBLK || vp->v_type == VCHR)) 201 ip->i_flag |= IN_LAZYMOD; 202 else 203 ip->i_flag |= IN_MODIFIED; 204 if ((vp->v_mount->mnt_flag & MNT_RDONLY) == 0) { 205 vfs_timestamp(&ts); 206 if (ip->i_flag & IN_ACCESS) { 207 ip->i_atime = ts.tv_sec; 208 ip->i_atimensec = ts.tv_nsec; 209 } 210 if (ip->i_flag & IN_UPDATE) { 211 ip->i_mtime = ts.tv_sec; 212 ip->i_mtimensec = ts.tv_nsec; 213 ip->i_modrev++; 214 } 215 if (ip->i_flag & IN_CHANGE) { 216 ip->i_ctime = ts.tv_sec; 217 ip->i_ctimensec = ts.tv_nsec; 218 } 219 } 220 ip->i_flag &= ~(IN_ACCESS | IN_CHANGE | IN_UPDATE); 221 } 222 223 void 224 ext2_itimes(struct vnode *vp) 225 { 226 227 VI_LOCK(vp); 228 ext2_itimes_locked(vp); 229 VI_UNLOCK(vp); 230 } 231 232 /* 233 * Create a regular file 234 */ 235 static int 236 ext2_create(struct vop_create_args *ap) 237 { 238 int error; 239 240 error = 241 ext2_makeinode(MAKEIMODE(ap->a_vap->va_type, ap->a_vap->va_mode), 242 ap->a_dvp, ap->a_vpp, ap->a_cnp); 243 if (error != 0) 244 return (error); 245 if ((ap->a_cnp->cn_flags & MAKEENTRY) != 0) 246 cache_enter(ap->a_dvp, *ap->a_vpp, ap->a_cnp); 247 return (0); 248 } 249 250 static int 251 ext2_open(struct vop_open_args *ap) 252 { 253 254 if (ap->a_vp->v_type == VBLK || ap->a_vp->v_type == VCHR) 255 return (EOPNOTSUPP); 256 257 /* 258 * Files marked append-only must be opened for appending. 259 */ 260 if ((VTOI(ap->a_vp)->i_flags & APPEND) && 261 (ap->a_mode & (FWRITE | O_APPEND)) == FWRITE) 262 return (EPERM); 263 264 vnode_create_vobject(ap->a_vp, VTOI(ap->a_vp)->i_size, ap->a_td); 265 266 return (0); 267 } 268 269 /* 270 * Close called. 271 * 272 * Update the times on the inode. 273 */ 274 static int 275 ext2_close(struct vop_close_args *ap) 276 { 277 struct vnode *vp = ap->a_vp; 278 279 VI_LOCK(vp); 280 if (vp->v_usecount > 1) 281 ext2_itimes_locked(vp); 282 VI_UNLOCK(vp); 283 return (0); 284 } 285 286 static int 287 ext2_access(struct vop_access_args *ap) 288 { 289 struct vnode *vp = ap->a_vp; 290 struct inode *ip = VTOI(vp); 291 accmode_t accmode = ap->a_accmode; 292 int error; 293 294 if (vp->v_type == VBLK || vp->v_type == VCHR) 295 return (EOPNOTSUPP); 296 297 /* 298 * Disallow write attempts on read-only file systems; 299 * unless the file is a socket, fifo, or a block or 300 * character device resident on the file system. 301 */ 302 if (accmode & VWRITE) { 303 switch (vp->v_type) { 304 case VDIR: 305 case VLNK: 306 case VREG: 307 if (vp->v_mount->mnt_flag & MNT_RDONLY) 308 return (EROFS); 309 break; 310 default: 311 break; 312 } 313 } 314 315 /* If immutable bit set, nobody gets to write it. */ 316 if ((accmode & VWRITE) && (ip->i_flags & (SF_IMMUTABLE | SF_SNAPSHOT))) 317 return (EPERM); 318 319 error = vaccess(vp->v_type, ip->i_mode, ip->i_uid, ip->i_gid, 320 ap->a_accmode, ap->a_cred, NULL); 321 return (error); 322 } 323 324 static int 325 ext2_getattr(struct vop_getattr_args *ap) 326 { 327 struct vnode *vp = ap->a_vp; 328 struct inode *ip = VTOI(vp); 329 struct vattr *vap = ap->a_vap; 330 331 ext2_itimes(vp); 332 /* 333 * Copy from inode table 334 */ 335 vap->va_fsid = dev2udev(ip->i_devvp->v_rdev); 336 vap->va_fileid = ip->i_number; 337 vap->va_mode = ip->i_mode & ~IFMT; 338 vap->va_nlink = ip->i_nlink; 339 vap->va_uid = ip->i_uid; 340 vap->va_gid = ip->i_gid; 341 vap->va_rdev = ip->i_rdev; 342 vap->va_size = ip->i_size; 343 vap->va_atime.tv_sec = ip->i_atime; 344 vap->va_atime.tv_nsec = E2DI_HAS_XTIME(ip) ? ip->i_atimensec : 0; 345 vap->va_mtime.tv_sec = ip->i_mtime; 346 vap->va_mtime.tv_nsec = E2DI_HAS_XTIME(ip) ? ip->i_mtimensec : 0; 347 vap->va_ctime.tv_sec = ip->i_ctime; 348 vap->va_ctime.tv_nsec = E2DI_HAS_XTIME(ip) ? ip->i_ctimensec : 0; 349 if E2DI_HAS_XTIME(ip) { 350 vap->va_birthtime.tv_sec = ip->i_birthtime; 351 vap->va_birthtime.tv_nsec = ip->i_birthnsec; 352 } 353 vap->va_flags = ip->i_flags; 354 vap->va_gen = ip->i_gen; 355 vap->va_blocksize = vp->v_mount->mnt_stat.f_iosize; 356 vap->va_bytes = dbtob((u_quad_t)ip->i_blocks); 357 vap->va_type = IFTOVT(ip->i_mode); 358 vap->va_filerev = ip->i_modrev; 359 return (0); 360 } 361 362 /* 363 * Set attribute vnode op. called from several syscalls 364 */ 365 static int 366 ext2_setattr(struct vop_setattr_args *ap) 367 { 368 struct vattr *vap = ap->a_vap; 369 struct vnode *vp = ap->a_vp; 370 struct inode *ip = VTOI(vp); 371 struct ucred *cred = ap->a_cred; 372 struct thread *td = curthread; 373 int error; 374 375 /* 376 * Check for unsettable attributes. 377 */ 378 if ((vap->va_type != VNON) || (vap->va_nlink != VNOVAL) || 379 (vap->va_fsid != VNOVAL) || (vap->va_fileid != VNOVAL) || 380 (vap->va_blocksize != VNOVAL) || (vap->va_rdev != VNOVAL) || 381 ((int)vap->va_bytes != VNOVAL) || (vap->va_gen != VNOVAL)) { 382 return (EINVAL); 383 } 384 if (vap->va_flags != VNOVAL) { 385 /* Disallow flags not supported by ext2fs. */ 386 if (vap->va_flags & ~(SF_APPEND | SF_IMMUTABLE | UF_NODUMP)) 387 return (EOPNOTSUPP); 388 389 if (vp->v_mount->mnt_flag & MNT_RDONLY) 390 return (EROFS); 391 /* 392 * Callers may only modify the file flags on objects they 393 * have VADMIN rights for. 394 */ 395 if ((error = VOP_ACCESS(vp, VADMIN, cred, td))) 396 return (error); 397 /* 398 * Unprivileged processes and privileged processes in 399 * jail() are not permitted to unset system flags, or 400 * modify flags if any system flags are set. 401 * Privileged non-jail processes may not modify system flags 402 * if securelevel > 0 and any existing system flags are set. 403 */ 404 if (!priv_check_cred(cred, PRIV_VFS_SYSFLAGS, 0)) { 405 if (ip->i_flags & (SF_IMMUTABLE | SF_APPEND)) { 406 error = securelevel_gt(cred, 0); 407 if (error) 408 return (error); 409 } 410 } else { 411 if (ip->i_flags & (SF_IMMUTABLE | SF_APPEND) || 412 ((vap->va_flags ^ ip->i_flags) & SF_SETTABLE)) 413 return (EPERM); 414 } 415 ip->i_flags = vap->va_flags; 416 ip->i_flag |= IN_CHANGE; 417 if (ip->i_flags & (IMMUTABLE | APPEND)) 418 return (0); 419 } 420 if (ip->i_flags & (IMMUTABLE | APPEND)) 421 return (EPERM); 422 /* 423 * Go through the fields and update iff not VNOVAL. 424 */ 425 if (vap->va_uid != (uid_t)VNOVAL || vap->va_gid != (gid_t)VNOVAL) { 426 if (vp->v_mount->mnt_flag & MNT_RDONLY) 427 return (EROFS); 428 if ((error = ext2_chown(vp, vap->va_uid, vap->va_gid, cred, 429 td)) != 0) 430 return (error); 431 } 432 if (vap->va_size != VNOVAL) { 433 /* 434 * Disallow write attempts on read-only file systems; 435 * unless the file is a socket, fifo, or a block or 436 * character device resident on the file system. 437 */ 438 switch (vp->v_type) { 439 case VDIR: 440 return (EISDIR); 441 case VLNK: 442 case VREG: 443 if (vp->v_mount->mnt_flag & MNT_RDONLY) 444 return (EROFS); 445 break; 446 default: 447 break; 448 } 449 if ((error = ext2_truncate(vp, vap->va_size, 0, cred, td)) != 0) 450 return (error); 451 } 452 if (vap->va_atime.tv_sec != VNOVAL || vap->va_mtime.tv_sec != VNOVAL) { 453 if (vp->v_mount->mnt_flag & MNT_RDONLY) 454 return (EROFS); 455 /* 456 * From utimes(2): 457 * If times is NULL, ... The caller must be the owner of 458 * the file, have permission to write the file, or be the 459 * super-user. 460 * If times is non-NULL, ... The caller must be the owner of 461 * the file or be the super-user. 462 */ 463 if ((error = VOP_ACCESS(vp, VADMIN, cred, td)) && 464 ((vap->va_vaflags & VA_UTIMES_NULL) == 0 || 465 (error = VOP_ACCESS(vp, VWRITE, cred, td)))) 466 return (error); 467 ip->i_flag |= IN_CHANGE | IN_MODIFIED; 468 if (vap->va_atime.tv_sec != VNOVAL) { 469 ip->i_flag &= ~IN_ACCESS; 470 ip->i_atime = vap->va_atime.tv_sec; 471 ip->i_atimensec = vap->va_atime.tv_nsec; 472 } 473 if (vap->va_mtime.tv_sec != VNOVAL) { 474 ip->i_flag &= ~IN_UPDATE; 475 ip->i_mtime = vap->va_mtime.tv_sec; 476 ip->i_mtimensec = vap->va_mtime.tv_nsec; 477 } 478 ip->i_birthtime = vap->va_birthtime.tv_sec; 479 ip->i_birthnsec = vap->va_birthtime.tv_nsec; 480 error = ext2_update(vp, 0); 481 if (error) 482 return (error); 483 } 484 error = 0; 485 if (vap->va_mode != (mode_t)VNOVAL) { 486 if (vp->v_mount->mnt_flag & MNT_RDONLY) 487 return (EROFS); 488 error = ext2_chmod(vp, (int)vap->va_mode, cred, td); 489 } 490 return (error); 491 } 492 493 /* 494 * Change the mode on a file. 495 * Inode must be locked before calling. 496 */ 497 static int 498 ext2_chmod(struct vnode *vp, int mode, struct ucred *cred, struct thread *td) 499 { 500 struct inode *ip = VTOI(vp); 501 int error; 502 503 /* 504 * To modify the permissions on a file, must possess VADMIN 505 * for that file. 506 */ 507 if ((error = VOP_ACCESS(vp, VADMIN, cred, td))) 508 return (error); 509 /* 510 * Privileged processes may set the sticky bit on non-directories, 511 * as well as set the setgid bit on a file with a group that the 512 * process is not a member of. 513 */ 514 if (vp->v_type != VDIR && (mode & S_ISTXT)) { 515 error = priv_check_cred(cred, PRIV_VFS_STICKYFILE, 0); 516 if (error) 517 return (EFTYPE); 518 } 519 if (!groupmember(ip->i_gid, cred) && (mode & ISGID)) { 520 error = priv_check_cred(cred, PRIV_VFS_SETGID, 0); 521 if (error) 522 return (error); 523 } 524 ip->i_mode &= ~ALLPERMS; 525 ip->i_mode |= (mode & ALLPERMS); 526 ip->i_flag |= IN_CHANGE; 527 return (0); 528 } 529 530 /* 531 * Perform chown operation on inode ip; 532 * inode must be locked prior to call. 533 */ 534 static int 535 ext2_chown(struct vnode *vp, uid_t uid, gid_t gid, struct ucred *cred, 536 struct thread *td) 537 { 538 struct inode *ip = VTOI(vp); 539 uid_t ouid; 540 gid_t ogid; 541 int error = 0; 542 543 if (uid == (uid_t)VNOVAL) 544 uid = ip->i_uid; 545 if (gid == (gid_t)VNOVAL) 546 gid = ip->i_gid; 547 /* 548 * To modify the ownership of a file, must possess VADMIN 549 * for that file. 550 */ 551 if ((error = VOP_ACCESS(vp, VADMIN, cred, td))) 552 return (error); 553 /* 554 * To change the owner of a file, or change the group of a file 555 * to a group of which we are not a member, the caller must 556 * have privilege. 557 */ 558 if (uid != ip->i_uid || (gid != ip->i_gid && 559 !groupmember(gid, cred))) { 560 error = priv_check_cred(cred, PRIV_VFS_CHOWN, 0); 561 if (error) 562 return (error); 563 } 564 ogid = ip->i_gid; 565 ouid = ip->i_uid; 566 ip->i_gid = gid; 567 ip->i_uid = uid; 568 ip->i_flag |= IN_CHANGE; 569 if ((ip->i_mode & (ISUID | ISGID)) && (ouid != uid || ogid != gid)) { 570 if (priv_check_cred(cred, PRIV_VFS_RETAINSUGID, 0) != 0) 571 ip->i_mode &= ~(ISUID | ISGID); 572 } 573 return (0); 574 } 575 576 /* 577 * Synch an open file. 578 */ 579 /* ARGSUSED */ 580 static int 581 ext2_fsync(struct vop_fsync_args *ap) 582 { 583 /* 584 * Flush all dirty buffers associated with a vnode. 585 */ 586 587 vop_stdfsync(ap); 588 589 return (ext2_update(ap->a_vp, ap->a_waitfor == MNT_WAIT)); 590 } 591 592 /* 593 * Mknod vnode call 594 */ 595 /* ARGSUSED */ 596 static int 597 ext2_mknod(struct vop_mknod_args *ap) 598 { 599 struct vattr *vap = ap->a_vap; 600 struct vnode **vpp = ap->a_vpp; 601 struct inode *ip; 602 ino_t ino; 603 int error; 604 605 error = ext2_makeinode(MAKEIMODE(vap->va_type, vap->va_mode), 606 ap->a_dvp, vpp, ap->a_cnp); 607 if (error) 608 return (error); 609 ip = VTOI(*vpp); 610 ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE; 611 if (vap->va_rdev != VNOVAL) { 612 /* 613 * Want to be able to use this to make badblock 614 * inodes, so don't truncate the dev number. 615 */ 616 ip->i_rdev = vap->va_rdev; 617 } 618 /* 619 * Remove inode, then reload it through VFS_VGET so it is 620 * checked to see if it is an alias of an existing entry in 621 * the inode cache. XXX I don't believe this is necessary now. 622 */ 623 (*vpp)->v_type = VNON; 624 ino = ip->i_number; /* Save this before vgone() invalidates ip. */ 625 vgone(*vpp); 626 vput(*vpp); 627 error = VFS_VGET(ap->a_dvp->v_mount, ino, LK_EXCLUSIVE, vpp); 628 if (error) { 629 *vpp = NULL; 630 return (error); 631 } 632 return (0); 633 } 634 635 static int 636 ext2_remove(struct vop_remove_args *ap) 637 { 638 struct inode *ip; 639 struct vnode *vp = ap->a_vp; 640 struct vnode *dvp = ap->a_dvp; 641 int error; 642 643 ip = VTOI(vp); 644 if ((ip->i_flags & (NOUNLINK | IMMUTABLE | APPEND)) || 645 (VTOI(dvp)->i_flags & APPEND)) { 646 error = EPERM; 647 goto out; 648 } 649 error = ext2_dirremove(dvp, ap->a_cnp); 650 if (error == 0) { 651 ip->i_nlink--; 652 ip->i_flag |= IN_CHANGE; 653 } 654 out: 655 return (error); 656 } 657 658 /* 659 * link vnode call 660 */ 661 static int 662 ext2_link(struct vop_link_args *ap) 663 { 664 struct vnode *vp = ap->a_vp; 665 struct vnode *tdvp = ap->a_tdvp; 666 struct componentname *cnp = ap->a_cnp; 667 struct inode *ip; 668 int error; 669 670 #ifdef INVARIANTS 671 if ((cnp->cn_flags & HASBUF) == 0) 672 panic("ext2_link: no name"); 673 #endif 674 ip = VTOI(vp); 675 if ((nlink_t)ip->i_nlink >= EXT2_LINK_MAX) { 676 error = EMLINK; 677 goto out; 678 } 679 if (ip->i_flags & (IMMUTABLE | APPEND)) { 680 error = EPERM; 681 goto out; 682 } 683 ip->i_nlink++; 684 ip->i_flag |= IN_CHANGE; 685 error = ext2_update(vp, !DOINGASYNC(vp)); 686 if (!error) 687 error = ext2_direnter(ip, tdvp, cnp); 688 if (error) { 689 ip->i_nlink--; 690 ip->i_flag |= IN_CHANGE; 691 } 692 out: 693 return (error); 694 } 695 696 /* 697 * Rename system call. 698 * rename("foo", "bar"); 699 * is essentially 700 * unlink("bar"); 701 * link("foo", "bar"); 702 * unlink("foo"); 703 * but ``atomically''. Can't do full commit without saving state in the 704 * inode on disk which isn't feasible at this time. Best we can do is 705 * always guarantee the target exists. 706 * 707 * Basic algorithm is: 708 * 709 * 1) Bump link count on source while we're linking it to the 710 * target. This also ensure the inode won't be deleted out 711 * from underneath us while we work (it may be truncated by 712 * a concurrent `trunc' or `open' for creation). 713 * 2) Link source to destination. If destination already exists, 714 * delete it first. 715 * 3) Unlink source reference to inode if still around. If a 716 * directory was moved and the parent of the destination 717 * is different from the source, patch the ".." entry in the 718 * directory. 719 */ 720 static int 721 ext2_rename(struct vop_rename_args *ap) 722 { 723 struct vnode *tvp = ap->a_tvp; 724 struct vnode *tdvp = ap->a_tdvp; 725 struct vnode *fvp = ap->a_fvp; 726 struct vnode *fdvp = ap->a_fdvp; 727 struct componentname *tcnp = ap->a_tcnp; 728 struct componentname *fcnp = ap->a_fcnp; 729 struct inode *ip, *xp, *dp; 730 struct dirtemplate dirbuf; 731 int doingdirectory = 0, oldparent = 0, newparent = 0; 732 int error = 0; 733 u_char namlen; 734 735 #ifdef INVARIANTS 736 if ((tcnp->cn_flags & HASBUF) == 0 || 737 (fcnp->cn_flags & HASBUF) == 0) 738 panic("ext2_rename: no name"); 739 #endif 740 /* 741 * Check for cross-device rename. 742 */ 743 if ((fvp->v_mount != tdvp->v_mount) || 744 (tvp && (fvp->v_mount != tvp->v_mount))) { 745 error = EXDEV; 746 abortit: 747 if (tdvp == tvp) 748 vrele(tdvp); 749 else 750 vput(tdvp); 751 if (tvp) 752 vput(tvp); 753 vrele(fdvp); 754 vrele(fvp); 755 return (error); 756 } 757 758 if (tvp && ((VTOI(tvp)->i_flags & (NOUNLINK | IMMUTABLE | APPEND)) || 759 (VTOI(tdvp)->i_flags & APPEND))) { 760 error = EPERM; 761 goto abortit; 762 } 763 764 /* 765 * Renaming a file to itself has no effect. The upper layers should 766 * not call us in that case. Temporarily just warn if they do. 767 */ 768 if (fvp == tvp) { 769 printf("ext2_rename: fvp == tvp (can't happen)\n"); 770 error = 0; 771 goto abortit; 772 } 773 774 if ((error = vn_lock(fvp, LK_EXCLUSIVE)) != 0) 775 goto abortit; 776 dp = VTOI(fdvp); 777 ip = VTOI(fvp); 778 if (ip->i_nlink >= EXT2_LINK_MAX) { 779 VOP_UNLOCK(fvp, 0); 780 error = EMLINK; 781 goto abortit; 782 } 783 if ((ip->i_flags & (NOUNLINK | IMMUTABLE | APPEND)) 784 || (dp->i_flags & APPEND)) { 785 VOP_UNLOCK(fvp, 0); 786 error = EPERM; 787 goto abortit; 788 } 789 if ((ip->i_mode & IFMT) == IFDIR) { 790 /* 791 * Avoid ".", "..", and aliases of "." for obvious reasons. 792 */ 793 if ((fcnp->cn_namelen == 1 && fcnp->cn_nameptr[0] == '.') || 794 dp == ip || (fcnp->cn_flags | tcnp->cn_flags) & ISDOTDOT || 795 (ip->i_flag & IN_RENAME)) { 796 VOP_UNLOCK(fvp, 0); 797 error = EINVAL; 798 goto abortit; 799 } 800 ip->i_flag |= IN_RENAME; 801 oldparent = dp->i_number; 802 doingdirectory++; 803 } 804 vrele(fdvp); 805 806 /* 807 * When the target exists, both the directory 808 * and target vnodes are returned locked. 809 */ 810 dp = VTOI(tdvp); 811 xp = NULL; 812 if (tvp) 813 xp = VTOI(tvp); 814 815 /* 816 * 1) Bump link count while we're moving stuff 817 * around. If we crash somewhere before 818 * completing our work, the link count 819 * may be wrong, but correctable. 820 */ 821 ip->i_nlink++; 822 ip->i_flag |= IN_CHANGE; 823 if ((error = ext2_update(fvp, !DOINGASYNC(fvp))) != 0) { 824 VOP_UNLOCK(fvp, 0); 825 goto bad; 826 } 827 828 /* 829 * If ".." must be changed (ie the directory gets a new 830 * parent) then the source directory must not be in the 831 * directory hierarchy above the target, as this would 832 * orphan everything below the source directory. Also 833 * the user must have write permission in the source so 834 * as to be able to change "..". We must repeat the call 835 * to namei, as the parent directory is unlocked by the 836 * call to checkpath(). 837 */ 838 error = VOP_ACCESS(fvp, VWRITE, tcnp->cn_cred, tcnp->cn_thread); 839 VOP_UNLOCK(fvp, 0); 840 if (oldparent != dp->i_number) 841 newparent = dp->i_number; 842 if (doingdirectory && newparent) { 843 if (error) /* write access check above */ 844 goto bad; 845 if (xp != NULL) 846 vput(tvp); 847 error = ext2_checkpath(ip, dp, tcnp->cn_cred); 848 if (error) 849 goto out; 850 VREF(tdvp); 851 error = relookup(tdvp, &tvp, tcnp); 852 if (error) 853 goto out; 854 vrele(tdvp); 855 dp = VTOI(tdvp); 856 xp = NULL; 857 if (tvp) 858 xp = VTOI(tvp); 859 } 860 /* 861 * 2) If target doesn't exist, link the target 862 * to the source and unlink the source. 863 * Otherwise, rewrite the target directory 864 * entry to reference the source inode and 865 * expunge the original entry's existence. 866 */ 867 if (xp == NULL) { 868 if (dp->i_devvp != ip->i_devvp) 869 panic("ext2_rename: EXDEV"); 870 /* 871 * Account for ".." in new directory. 872 * When source and destination have the same 873 * parent we don't fool with the link count. 874 */ 875 if (doingdirectory && newparent) { 876 if ((nlink_t)dp->i_nlink >= EXT2_LINK_MAX) { 877 error = EMLINK; 878 goto bad; 879 } 880 dp->i_nlink++; 881 dp->i_flag |= IN_CHANGE; 882 error = ext2_update(tdvp, !DOINGASYNC(tdvp)); 883 if (error) 884 goto bad; 885 } 886 error = ext2_direnter(ip, tdvp, tcnp); 887 if (error) { 888 if (doingdirectory && newparent) { 889 dp->i_nlink--; 890 dp->i_flag |= IN_CHANGE; 891 (void)ext2_update(tdvp, 1); 892 } 893 goto bad; 894 } 895 vput(tdvp); 896 } else { 897 if (xp->i_devvp != dp->i_devvp || xp->i_devvp != ip->i_devvp) 898 panic("ext2_rename: EXDEV"); 899 /* 900 * Short circuit rename(foo, foo). 901 */ 902 if (xp->i_number == ip->i_number) 903 panic("ext2_rename: same file"); 904 /* 905 * If the parent directory is "sticky", then the user must 906 * own the parent directory, or the destination of the rename, 907 * otherwise the destination may not be changed (except by 908 * root). This implements append-only directories. 909 */ 910 if ((dp->i_mode & S_ISTXT) && tcnp->cn_cred->cr_uid != 0 && 911 tcnp->cn_cred->cr_uid != dp->i_uid && 912 xp->i_uid != tcnp->cn_cred->cr_uid) { 913 error = EPERM; 914 goto bad; 915 } 916 /* 917 * Target must be empty if a directory and have no links 918 * to it. Also, ensure source and target are compatible 919 * (both directories, or both not directories). 920 */ 921 if ((xp->i_mode & IFMT) == IFDIR) { 922 if (!ext2_dirempty(xp, dp->i_number, tcnp->cn_cred) || 923 xp->i_nlink > 2) { 924 error = ENOTEMPTY; 925 goto bad; 926 } 927 if (!doingdirectory) { 928 error = ENOTDIR; 929 goto bad; 930 } 931 cache_purge(tdvp); 932 } else if (doingdirectory) { 933 error = EISDIR; 934 goto bad; 935 } 936 error = ext2_dirrewrite(dp, ip, tcnp); 937 if (error) 938 goto bad; 939 /* 940 * If the target directory is in the same 941 * directory as the source directory, 942 * decrement the link count on the parent 943 * of the target directory. 944 */ 945 if (doingdirectory && !newparent) { 946 dp->i_nlink--; 947 dp->i_flag |= IN_CHANGE; 948 } 949 vput(tdvp); 950 /* 951 * Adjust the link count of the target to 952 * reflect the dirrewrite above. If this is 953 * a directory it is empty and there are 954 * no links to it, so we can squash the inode and 955 * any space associated with it. We disallowed 956 * renaming over top of a directory with links to 957 * it above, as the remaining link would point to 958 * a directory without "." or ".." entries. 959 */ 960 xp->i_nlink--; 961 if (doingdirectory) { 962 if (--xp->i_nlink != 0) 963 panic("ext2_rename: linked directory"); 964 error = ext2_truncate(tvp, (off_t)0, IO_SYNC, 965 tcnp->cn_cred, tcnp->cn_thread); 966 } 967 xp->i_flag |= IN_CHANGE; 968 vput(tvp); 969 xp = NULL; 970 } 971 972 /* 973 * 3) Unlink the source. 974 */ 975 fcnp->cn_flags &= ~MODMASK; 976 fcnp->cn_flags |= LOCKPARENT | LOCKLEAF; 977 VREF(fdvp); 978 error = relookup(fdvp, &fvp, fcnp); 979 if (error == 0) 980 vrele(fdvp); 981 if (fvp != NULL) { 982 xp = VTOI(fvp); 983 dp = VTOI(fdvp); 984 } else { 985 /* 986 * From name has disappeared. IN_RENAME is not sufficient 987 * to protect against directory races due to timing windows, 988 * so we can't panic here. 989 */ 990 vrele(ap->a_fvp); 991 return (0); 992 } 993 /* 994 * Ensure that the directory entry still exists and has not 995 * changed while the new name has been entered. If the source is 996 * a file then the entry may have been unlinked or renamed. In 997 * either case there is no further work to be done. If the source 998 * is a directory then it cannot have been rmdir'ed; its link 999 * count of three would cause a rmdir to fail with ENOTEMPTY. 1000 * The IN_RENAME flag ensures that it cannot be moved by another 1001 * rename. 1002 */ 1003 if (xp != ip) { 1004 /* 1005 * From name resolves to a different inode. IN_RENAME is 1006 * not sufficient protection against timing window races 1007 * so we can't panic here. 1008 */ 1009 } else { 1010 /* 1011 * If the source is a directory with a 1012 * new parent, the link count of the old 1013 * parent directory must be decremented 1014 * and ".." set to point to the new parent. 1015 */ 1016 if (doingdirectory && newparent) { 1017 dp->i_nlink--; 1018 dp->i_flag |= IN_CHANGE; 1019 error = vn_rdwr(UIO_READ, fvp, (caddr_t)&dirbuf, 1020 sizeof(struct dirtemplate), (off_t)0, 1021 UIO_SYSSPACE, IO_NODELOCKED | IO_NOMACCHECK, 1022 tcnp->cn_cred, NOCRED, NULL, NULL); 1023 if (error == 0) { 1024 /* Like ufs little-endian: */ 1025 namlen = dirbuf.dotdot_type; 1026 if (namlen != 2 || 1027 dirbuf.dotdot_name[0] != '.' || 1028 dirbuf.dotdot_name[1] != '.') { 1029 ext2_dirbad(xp, (doff_t)12, 1030 "rename: mangled dir"); 1031 } else { 1032 dirbuf.dotdot_ino = newparent; 1033 (void)vn_rdwr(UIO_WRITE, fvp, 1034 (caddr_t)&dirbuf, 1035 sizeof(struct dirtemplate), 1036 (off_t)0, UIO_SYSSPACE, 1037 IO_NODELOCKED | IO_SYNC | 1038 IO_NOMACCHECK, tcnp->cn_cred, 1039 NOCRED, NULL, NULL); 1040 cache_purge(fdvp); 1041 } 1042 } 1043 } 1044 error = ext2_dirremove(fdvp, fcnp); 1045 if (!error) { 1046 xp->i_nlink--; 1047 xp->i_flag |= IN_CHANGE; 1048 } 1049 xp->i_flag &= ~IN_RENAME; 1050 } 1051 if (dp) 1052 vput(fdvp); 1053 if (xp) 1054 vput(fvp); 1055 vrele(ap->a_fvp); 1056 return (error); 1057 1058 bad: 1059 if (xp) 1060 vput(ITOV(xp)); 1061 vput(ITOV(dp)); 1062 out: 1063 if (doingdirectory) 1064 ip->i_flag &= ~IN_RENAME; 1065 if (vn_lock(fvp, LK_EXCLUSIVE) == 0) { 1066 ip->i_nlink--; 1067 ip->i_flag |= IN_CHANGE; 1068 ip->i_flag &= ~IN_RENAME; 1069 vput(fvp); 1070 } else 1071 vrele(fvp); 1072 return (error); 1073 } 1074 1075 /* 1076 * Mkdir system call 1077 */ 1078 static int 1079 ext2_mkdir(struct vop_mkdir_args *ap) 1080 { 1081 struct vnode *dvp = ap->a_dvp; 1082 struct vattr *vap = ap->a_vap; 1083 struct componentname *cnp = ap->a_cnp; 1084 struct inode *ip, *dp; 1085 struct vnode *tvp; 1086 struct dirtemplate dirtemplate, *dtp; 1087 int error, dmode; 1088 1089 #ifdef INVARIANTS 1090 if ((cnp->cn_flags & HASBUF) == 0) 1091 panic("ext2_mkdir: no name"); 1092 #endif 1093 dp = VTOI(dvp); 1094 if ((nlink_t)dp->i_nlink >= EXT2_LINK_MAX) { 1095 error = EMLINK; 1096 goto out; 1097 } 1098 dmode = vap->va_mode & 0777; 1099 dmode |= IFDIR; 1100 /* 1101 * Must simulate part of ext2_makeinode here to acquire the inode, 1102 * but not have it entered in the parent directory. The entry is 1103 * made later after writing "." and ".." entries. 1104 */ 1105 error = ext2_valloc(dvp, dmode, cnp->cn_cred, &tvp); 1106 if (error) 1107 goto out; 1108 ip = VTOI(tvp); 1109 ip->i_gid = dp->i_gid; 1110 #ifdef SUIDDIR 1111 { 1112 /* 1113 * if we are hacking owners here, (only do this where told to) 1114 * and we are not giving it TOO root, (would subvert quotas) 1115 * then go ahead and give it to the other user. 1116 * The new directory also inherits the SUID bit. 1117 * If user's UID and dir UID are the same, 1118 * 'give it away' so that the SUID is still forced on. 1119 */ 1120 if ((dvp->v_mount->mnt_flag & MNT_SUIDDIR) && 1121 (dp->i_mode & ISUID) && dp->i_uid) { 1122 dmode |= ISUID; 1123 ip->i_uid = dp->i_uid; 1124 } else { 1125 ip->i_uid = cnp->cn_cred->cr_uid; 1126 } 1127 } 1128 #else 1129 ip->i_uid = cnp->cn_cred->cr_uid; 1130 #endif 1131 ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE; 1132 ip->i_mode = dmode; 1133 tvp->v_type = VDIR; /* Rest init'd in getnewvnode(). */ 1134 ip->i_nlink = 2; 1135 if (cnp->cn_flags & ISWHITEOUT) 1136 ip->i_flags |= UF_OPAQUE; 1137 error = ext2_update(tvp, 1); 1138 1139 /* 1140 * Bump link count in parent directory 1141 * to reflect work done below. Should 1142 * be done before reference is created 1143 * so reparation is possible if we crash. 1144 */ 1145 dp->i_nlink++; 1146 dp->i_flag |= IN_CHANGE; 1147 error = ext2_update(dvp, !DOINGASYNC(dvp)); 1148 if (error) 1149 goto bad; 1150 1151 /* Initialize directory with "." and ".." from static template. */ 1152 if (EXT2_HAS_INCOMPAT_FEATURE(ip->i_e2fs, 1153 EXT2F_INCOMPAT_FTYPE)) 1154 dtp = &mastertemplate; 1155 else 1156 dtp = &omastertemplate; 1157 dirtemplate = *dtp; 1158 dirtemplate.dot_ino = ip->i_number; 1159 dirtemplate.dotdot_ino = dp->i_number; 1160 /* 1161 * note that in ext2 DIRBLKSIZ == blocksize, not DEV_BSIZE so let's 1162 * just redefine it - for this function only 1163 */ 1164 #undef DIRBLKSIZ 1165 #define DIRBLKSIZ VTOI(dvp)->i_e2fs->e2fs_bsize 1166 dirtemplate.dotdot_reclen = DIRBLKSIZ - 12; 1167 error = vn_rdwr(UIO_WRITE, tvp, (caddr_t)&dirtemplate, 1168 sizeof(dirtemplate), (off_t)0, UIO_SYSSPACE, 1169 IO_NODELOCKED | IO_SYNC | IO_NOMACCHECK, cnp->cn_cred, NOCRED, 1170 NULL, NULL); 1171 if (error) { 1172 dp->i_nlink--; 1173 dp->i_flag |= IN_CHANGE; 1174 goto bad; 1175 } 1176 if (DIRBLKSIZ > VFSTOEXT2(dvp->v_mount)->um_mountp->mnt_stat.f_bsize) 1177 /* XXX should grow with balloc() */ 1178 panic("ext2_mkdir: blksize"); 1179 else { 1180 ip->i_size = DIRBLKSIZ; 1181 ip->i_flag |= IN_CHANGE; 1182 } 1183 1184 /* Directory set up, now install its entry in the parent directory. */ 1185 error = ext2_direnter(ip, dvp, cnp); 1186 if (error) { 1187 dp->i_nlink--; 1188 dp->i_flag |= IN_CHANGE; 1189 } 1190 bad: 1191 /* 1192 * No need to do an explicit VOP_TRUNCATE here, vrele will do this 1193 * for us because we set the link count to 0. 1194 */ 1195 if (error) { 1196 ip->i_nlink = 0; 1197 ip->i_flag |= IN_CHANGE; 1198 vput(tvp); 1199 } else 1200 *ap->a_vpp = tvp; 1201 out: 1202 return (error); 1203 #undef DIRBLKSIZ 1204 #define DIRBLKSIZ DEV_BSIZE 1205 } 1206 1207 /* 1208 * Rmdir system call. 1209 */ 1210 static int 1211 ext2_rmdir(struct vop_rmdir_args *ap) 1212 { 1213 struct vnode *vp = ap->a_vp; 1214 struct vnode *dvp = ap->a_dvp; 1215 struct componentname *cnp = ap->a_cnp; 1216 struct inode *ip, *dp; 1217 int error; 1218 1219 ip = VTOI(vp); 1220 dp = VTOI(dvp); 1221 1222 /* 1223 * Verify the directory is empty (and valid). 1224 * (Rmdir ".." won't be valid since 1225 * ".." will contain a reference to 1226 * the current directory and thus be 1227 * non-empty.) 1228 */ 1229 if (ip->i_nlink != 2 || !ext2_dirempty(ip, dp->i_number, cnp->cn_cred)) { 1230 error = ENOTEMPTY; 1231 goto out; 1232 } 1233 if ((dp->i_flags & APPEND) 1234 || (ip->i_flags & (NOUNLINK | IMMUTABLE | APPEND))) { 1235 error = EPERM; 1236 goto out; 1237 } 1238 /* 1239 * Delete reference to directory before purging 1240 * inode. If we crash in between, the directory 1241 * will be reattached to lost+found, 1242 */ 1243 error = ext2_dirremove(dvp, cnp); 1244 if (error) 1245 goto out; 1246 dp->i_nlink--; 1247 dp->i_flag |= IN_CHANGE; 1248 cache_purge(dvp); 1249 VOP_UNLOCK(dvp, 0); 1250 /* 1251 * Truncate inode. The only stuff left 1252 * in the directory is "." and "..". The 1253 * "." reference is inconsequential since 1254 * we're quashing it. The ".." reference 1255 * has already been adjusted above. We've 1256 * removed the "." reference and the reference 1257 * in the parent directory, but there may be 1258 * other hard links so decrement by 2 and 1259 * worry about them later. 1260 */ 1261 ip->i_nlink -= 2; 1262 error = ext2_truncate(vp, (off_t)0, IO_SYNC, cnp->cn_cred, 1263 cnp->cn_thread); 1264 cache_purge(ITOV(ip)); 1265 if (vn_lock(dvp, LK_EXCLUSIVE | LK_NOWAIT) != 0) { 1266 VOP_UNLOCK(vp, 0); 1267 vn_lock(dvp, LK_EXCLUSIVE | LK_RETRY); 1268 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 1269 } 1270 out: 1271 return (error); 1272 } 1273 1274 /* 1275 * symlink -- make a symbolic link 1276 */ 1277 static int 1278 ext2_symlink(struct vop_symlink_args *ap) 1279 { 1280 struct vnode *vp, **vpp = ap->a_vpp; 1281 struct inode *ip; 1282 int len, error; 1283 1284 error = ext2_makeinode(IFLNK | ap->a_vap->va_mode, ap->a_dvp, 1285 vpp, ap->a_cnp); 1286 if (error) 1287 return (error); 1288 vp = *vpp; 1289 len = strlen(ap->a_target); 1290 if (len < vp->v_mount->mnt_maxsymlinklen) { 1291 ip = VTOI(vp); 1292 bcopy(ap->a_target, (char *)ip->i_shortlink, len); 1293 ip->i_size = len; 1294 ip->i_flag |= IN_CHANGE | IN_UPDATE; 1295 } else 1296 error = vn_rdwr(UIO_WRITE, vp, ap->a_target, len, (off_t)0, 1297 UIO_SYSSPACE, IO_NODELOCKED | IO_NOMACCHECK, 1298 ap->a_cnp->cn_cred, NOCRED, NULL, NULL); 1299 if (error) 1300 vput(vp); 1301 return (error); 1302 } 1303 1304 /* 1305 * Return target name of a symbolic link 1306 */ 1307 static int 1308 ext2_readlink(struct vop_readlink_args *ap) 1309 { 1310 struct vnode *vp = ap->a_vp; 1311 struct inode *ip = VTOI(vp); 1312 int isize; 1313 1314 isize = ip->i_size; 1315 if (isize < vp->v_mount->mnt_maxsymlinklen) { 1316 uiomove((char *)ip->i_shortlink, isize, ap->a_uio); 1317 return (0); 1318 } 1319 return (VOP_READ(vp, ap->a_uio, 0, ap->a_cred)); 1320 } 1321 1322 /* 1323 * Calculate the logical to physical mapping if not done already, 1324 * then call the device strategy routine. 1325 * 1326 * In order to be able to swap to a file, the ext2_bmaparray() operation may not 1327 * deadlock on memory. See ext2_bmap() for details. 1328 */ 1329 static int 1330 ext2_strategy(struct vop_strategy_args *ap) 1331 { 1332 struct buf *bp = ap->a_bp; 1333 struct vnode *vp = ap->a_vp; 1334 struct bufobj *bo; 1335 daddr_t blkno; 1336 int error; 1337 1338 if (vp->v_type == VBLK || vp->v_type == VCHR) 1339 panic("ext2_strategy: spec"); 1340 if (bp->b_blkno == bp->b_lblkno) { 1341 error = ext2_bmaparray(vp, bp->b_lblkno, &blkno, NULL, NULL); 1342 bp->b_blkno = blkno; 1343 if (error) { 1344 bp->b_error = error; 1345 bp->b_ioflags |= BIO_ERROR; 1346 bufdone(bp); 1347 return (0); 1348 } 1349 if ((long)bp->b_blkno == -1) 1350 vfs_bio_clrbuf(bp); 1351 } 1352 if ((long)bp->b_blkno == -1) { 1353 bufdone(bp); 1354 return (0); 1355 } 1356 bp->b_iooffset = dbtob(bp->b_blkno); 1357 bo = VFSTOEXT2(vp->v_mount)->um_bo; 1358 BO_STRATEGY(bo, bp); 1359 return (0); 1360 } 1361 1362 /* 1363 * Print out the contents of an inode. 1364 */ 1365 static int 1366 ext2_print(struct vop_print_args *ap) 1367 { 1368 struct vnode *vp = ap->a_vp; 1369 struct inode *ip = VTOI(vp); 1370 1371 vn_printf(ip->i_devvp, "\tino %ju", (uintmax_t)ip->i_number); 1372 if (vp->v_type == VFIFO) 1373 fifo_printinfo(vp); 1374 printf("\n"); 1375 return (0); 1376 } 1377 1378 /* 1379 * Close wrapper for fifos. 1380 * 1381 * Update the times on the inode then do device close. 1382 */ 1383 static int 1384 ext2fifo_close(struct vop_close_args *ap) 1385 { 1386 struct vnode *vp = ap->a_vp; 1387 1388 VI_LOCK(vp); 1389 if (vp->v_usecount > 1) 1390 ext2_itimes_locked(vp); 1391 VI_UNLOCK(vp); 1392 return (fifo_specops.vop_close(ap)); 1393 } 1394 1395 /* 1396 * Kqfilter wrapper for fifos. 1397 * 1398 * Fall through to ext2 kqfilter routines if needed 1399 */ 1400 static int 1401 ext2fifo_kqfilter(struct vop_kqfilter_args *ap) 1402 { 1403 int error; 1404 1405 error = fifo_specops.vop_kqfilter(ap); 1406 if (error) 1407 error = vfs_kqfilter(ap); 1408 return (error); 1409 } 1410 1411 /* 1412 * Return POSIX pathconf information applicable to ext2 filesystems. 1413 */ 1414 static int 1415 ext2_pathconf(struct vop_pathconf_args *ap) 1416 { 1417 int error = 0; 1418 1419 switch (ap->a_name) { 1420 case _PC_LINK_MAX: 1421 *ap->a_retval = EXT2_LINK_MAX; 1422 break; 1423 case _PC_NAME_MAX: 1424 *ap->a_retval = NAME_MAX; 1425 break; 1426 case _PC_PATH_MAX: 1427 *ap->a_retval = PATH_MAX; 1428 break; 1429 case _PC_PIPE_BUF: 1430 *ap->a_retval = PIPE_BUF; 1431 break; 1432 case _PC_CHOWN_RESTRICTED: 1433 *ap->a_retval = 1; 1434 break; 1435 case _PC_NO_TRUNC: 1436 *ap->a_retval = 1; 1437 break; 1438 case _PC_MIN_HOLE_SIZE: 1439 *ap->a_retval = ap->a_vp->v_mount->mnt_stat.f_iosize; 1440 break; 1441 case _PC_ASYNC_IO: 1442 /* _PC_ASYNC_IO should have been handled by upper layers. */ 1443 KASSERT(0, ("_PC_ASYNC_IO should not get here")); 1444 error = EINVAL; 1445 break; 1446 case _PC_PRIO_IO: 1447 *ap->a_retval = 0; 1448 break; 1449 case _PC_SYNC_IO: 1450 *ap->a_retval = 0; 1451 break; 1452 case _PC_ALLOC_SIZE_MIN: 1453 *ap->a_retval = ap->a_vp->v_mount->mnt_stat.f_bsize; 1454 break; 1455 case _PC_FILESIZEBITS: 1456 *ap->a_retval = 64; 1457 break; 1458 case _PC_REC_INCR_XFER_SIZE: 1459 *ap->a_retval = ap->a_vp->v_mount->mnt_stat.f_iosize; 1460 break; 1461 case _PC_REC_MAX_XFER_SIZE: 1462 *ap->a_retval = -1; /* means ``unlimited'' */ 1463 break; 1464 case _PC_REC_MIN_XFER_SIZE: 1465 *ap->a_retval = ap->a_vp->v_mount->mnt_stat.f_iosize; 1466 break; 1467 case _PC_REC_XFER_ALIGN: 1468 *ap->a_retval = PAGE_SIZE; 1469 break; 1470 case _PC_SYMLINK_MAX: 1471 *ap->a_retval = MAXPATHLEN; 1472 break; 1473 1474 default: 1475 error = EINVAL; 1476 break; 1477 } 1478 return (error); 1479 } 1480 1481 /* 1482 * Vnode pointer to File handle 1483 */ 1484 /* ARGSUSED */ 1485 static int 1486 ext2_vptofh(struct vop_vptofh_args *ap) 1487 { 1488 struct inode *ip; 1489 struct ufid *ufhp; 1490 1491 ip = VTOI(ap->a_vp); 1492 ufhp = (struct ufid *)ap->a_fhp; 1493 ufhp->ufid_len = sizeof(struct ufid); 1494 ufhp->ufid_ino = ip->i_number; 1495 ufhp->ufid_gen = ip->i_gen; 1496 return (0); 1497 } 1498 1499 /* 1500 * Initialize the vnode associated with a new inode, handle aliased 1501 * vnodes. 1502 */ 1503 int 1504 ext2_vinit(struct mount *mntp, struct vop_vector *fifoops, struct vnode **vpp) 1505 { 1506 struct inode *ip; 1507 struct vnode *vp; 1508 1509 vp = *vpp; 1510 ip = VTOI(vp); 1511 vp->v_type = IFTOVT(ip->i_mode); 1512 if (vp->v_type == VFIFO) 1513 vp->v_op = fifoops; 1514 1515 if (ip->i_number == EXT2_ROOTINO) 1516 vp->v_vflag |= VV_ROOT; 1517 ip->i_modrev = init_va_filerev(); 1518 *vpp = vp; 1519 return (0); 1520 } 1521 1522 /* 1523 * Allocate a new inode. 1524 */ 1525 static int 1526 ext2_makeinode(int mode, struct vnode *dvp, struct vnode **vpp, 1527 struct componentname *cnp) 1528 { 1529 struct inode *ip, *pdir; 1530 struct vnode *tvp; 1531 int error; 1532 1533 pdir = VTOI(dvp); 1534 #ifdef INVARIANTS 1535 if ((cnp->cn_flags & HASBUF) == 0) 1536 panic("ext2_makeinode: no name"); 1537 #endif 1538 *vpp = NULL; 1539 if ((mode & IFMT) == 0) 1540 mode |= IFREG; 1541 1542 error = ext2_valloc(dvp, mode, cnp->cn_cred, &tvp); 1543 if (error) { 1544 return (error); 1545 } 1546 ip = VTOI(tvp); 1547 ip->i_gid = pdir->i_gid; 1548 #ifdef SUIDDIR 1549 { 1550 /* 1551 * if we are 1552 * not the owner of the directory, 1553 * and we are hacking owners here, (only do this where told to) 1554 * and we are not giving it TOO root, (would subvert quotas) 1555 * then go ahead and give it to the other user. 1556 * Note that this drops off the execute bits for security. 1557 */ 1558 if ((dvp->v_mount->mnt_flag & MNT_SUIDDIR) && 1559 (pdir->i_mode & ISUID) && 1560 (pdir->i_uid != cnp->cn_cred->cr_uid) && pdir->i_uid) { 1561 ip->i_uid = pdir->i_uid; 1562 mode &= ~07111; 1563 } else { 1564 ip->i_uid = cnp->cn_cred->cr_uid; 1565 } 1566 } 1567 #else 1568 ip->i_uid = cnp->cn_cred->cr_uid; 1569 #endif 1570 ip->i_flag |= IN_ACCESS | IN_CHANGE | IN_UPDATE; 1571 ip->i_mode = mode; 1572 tvp->v_type = IFTOVT(mode); /* Rest init'd in getnewvnode(). */ 1573 ip->i_nlink = 1; 1574 if ((ip->i_mode & ISGID) && !groupmember(ip->i_gid, cnp->cn_cred)) { 1575 if (priv_check_cred(cnp->cn_cred, PRIV_VFS_RETAINSUGID, 0)) 1576 ip->i_mode &= ~ISGID; 1577 } 1578 1579 if (cnp->cn_flags & ISWHITEOUT) 1580 ip->i_flags |= UF_OPAQUE; 1581 1582 /* 1583 * Make sure inode goes to disk before directory entry. 1584 */ 1585 error = ext2_update(tvp, !DOINGASYNC(tvp)); 1586 if (error) 1587 goto bad; 1588 error = ext2_direnter(ip, dvp, cnp); 1589 if (error) 1590 goto bad; 1591 1592 *vpp = tvp; 1593 return (0); 1594 1595 bad: 1596 /* 1597 * Write error occurred trying to update the inode 1598 * or the directory so must deallocate the inode. 1599 */ 1600 ip->i_nlink = 0; 1601 ip->i_flag |= IN_CHANGE; 1602 vput(tvp); 1603 return (error); 1604 } 1605 1606 /* 1607 * Vnode op for reading. 1608 */ 1609 static int 1610 ext2_read(struct vop_read_args *ap) 1611 { 1612 struct vnode *vp; 1613 struct inode *ip; 1614 int error; 1615 1616 vp = ap->a_vp; 1617 ip = VTOI(vp); 1618 1619 /* EXT4_EXT_LOCK(ip); */ 1620 if (ip->i_flag & IN_E4EXTENTS) 1621 error = ext4_ext_read(ap); 1622 else 1623 error = ext2_ind_read(ap); 1624 /* EXT4_EXT_UNLOCK(ip); */ 1625 return (error); 1626 } 1627 1628 /* 1629 * Vnode op for reading. 1630 */ 1631 static int 1632 ext2_ind_read(struct vop_read_args *ap) 1633 { 1634 struct vnode *vp; 1635 struct inode *ip; 1636 struct uio *uio; 1637 struct m_ext2fs *fs; 1638 struct buf *bp; 1639 daddr_t lbn, nextlbn; 1640 off_t bytesinfile; 1641 long size, xfersize, blkoffset; 1642 int error, orig_resid, seqcount; 1643 int ioflag; 1644 1645 vp = ap->a_vp; 1646 uio = ap->a_uio; 1647 ioflag = ap->a_ioflag; 1648 1649 seqcount = ap->a_ioflag >> IO_SEQSHIFT; 1650 ip = VTOI(vp); 1651 1652 #ifdef INVARIANTS 1653 if (uio->uio_rw != UIO_READ) 1654 panic("%s: mode", "ext2_read"); 1655 1656 if (vp->v_type == VLNK) { 1657 if ((int)ip->i_size < vp->v_mount->mnt_maxsymlinklen) 1658 panic("%s: short symlink", "ext2_read"); 1659 } else if (vp->v_type != VREG && vp->v_type != VDIR) 1660 panic("%s: type %d", "ext2_read", vp->v_type); 1661 #endif 1662 orig_resid = uio->uio_resid; 1663 KASSERT(orig_resid >= 0, ("ext2_read: uio->uio_resid < 0")); 1664 if (orig_resid == 0) 1665 return (0); 1666 KASSERT(uio->uio_offset >= 0, ("ext2_read: uio->uio_offset < 0")); 1667 fs = ip->i_e2fs; 1668 if (uio->uio_offset < ip->i_size && 1669 uio->uio_offset >= fs->e2fs_maxfilesize) 1670 return (EOVERFLOW); 1671 1672 for (error = 0, bp = NULL; uio->uio_resid > 0; bp = NULL) { 1673 if ((bytesinfile = ip->i_size - uio->uio_offset) <= 0) 1674 break; 1675 lbn = lblkno(fs, uio->uio_offset); 1676 nextlbn = lbn + 1; 1677 size = blksize(fs, ip, lbn); 1678 blkoffset = blkoff(fs, uio->uio_offset); 1679 1680 xfersize = fs->e2fs_fsize - blkoffset; 1681 if (uio->uio_resid < xfersize) 1682 xfersize = uio->uio_resid; 1683 if (bytesinfile < xfersize) 1684 xfersize = bytesinfile; 1685 1686 if (lblktosize(fs, nextlbn) >= ip->i_size) 1687 error = bread(vp, lbn, size, NOCRED, &bp); 1688 else if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERR) == 0) { 1689 error = cluster_read(vp, ip->i_size, lbn, size, 1690 NOCRED, blkoffset + uio->uio_resid, seqcount, 1691 0, &bp); 1692 } else if (seqcount > 1) { 1693 u_int nextsize = blksize(fs, ip, nextlbn); 1694 1695 error = breadn(vp, lbn, 1696 size, &nextlbn, &nextsize, 1, NOCRED, &bp); 1697 } else 1698 error = bread(vp, lbn, size, NOCRED, &bp); 1699 if (error) { 1700 brelse(bp); 1701 bp = NULL; 1702 break; 1703 } 1704 1705 /* 1706 * We should only get non-zero b_resid when an I/O error 1707 * has occurred, which should cause us to break above. 1708 * However, if the short read did not cause an error, 1709 * then we want to ensure that we do not uiomove bad 1710 * or uninitialized data. 1711 */ 1712 size -= bp->b_resid; 1713 if (size < xfersize) { 1714 if (size == 0) 1715 break; 1716 xfersize = size; 1717 } 1718 error = uiomove((char *)bp->b_data + blkoffset, 1719 (int)xfersize, uio); 1720 if (error) 1721 break; 1722 vfs_bio_brelse(bp, ioflag); 1723 } 1724 1725 /* 1726 * This can only happen in the case of an error because the loop 1727 * above resets bp to NULL on each iteration and on normal 1728 * completion has not set a new value into it. so it must have come 1729 * from a 'break' statement 1730 */ 1731 if (bp != NULL) 1732 vfs_bio_brelse(bp, ioflag); 1733 1734 if ((error == 0 || uio->uio_resid != orig_resid) && 1735 (vp->v_mount->mnt_flag & (MNT_NOATIME | MNT_RDONLY)) == 0) 1736 ip->i_flag |= IN_ACCESS; 1737 return (error); 1738 } 1739 1740 static int 1741 ext2_ioctl(struct vop_ioctl_args *ap) 1742 { 1743 1744 switch (ap->a_command) { 1745 case FIOSEEKDATA: 1746 case FIOSEEKHOLE: 1747 return (vn_bmap_seekhole(ap->a_vp, ap->a_command, 1748 (off_t *)ap->a_data, ap->a_cred)); 1749 default: 1750 return (ENOTTY); 1751 } 1752 } 1753 1754 /* 1755 * this function handles ext4 extents block mapping 1756 */ 1757 static int 1758 ext4_ext_read(struct vop_read_args *ap) 1759 { 1760 static unsigned char zeroes[EXT2_MAX_BLOCK_SIZE]; 1761 struct vnode *vp; 1762 struct inode *ip; 1763 struct uio *uio; 1764 struct m_ext2fs *fs; 1765 struct buf *bp; 1766 struct ext4_extent nex, *ep; 1767 struct ext4_extent_path path; 1768 daddr_t lbn, newblk; 1769 off_t bytesinfile; 1770 int cache_type; 1771 ssize_t orig_resid; 1772 int error; 1773 long size, xfersize, blkoffset; 1774 1775 vp = ap->a_vp; 1776 ip = VTOI(vp); 1777 uio = ap->a_uio; 1778 memset(&path, 0, sizeof(path)); 1779 1780 orig_resid = uio->uio_resid; 1781 KASSERT(orig_resid >= 0, ("%s: uio->uio_resid < 0", __func__)); 1782 if (orig_resid == 0) 1783 return (0); 1784 KASSERT(uio->uio_offset >= 0, ("%s: uio->uio_offset < 0", __func__)); 1785 fs = ip->i_e2fs; 1786 if (uio->uio_offset < ip->i_size && uio->uio_offset >= fs->e2fs_maxfilesize) 1787 return (EOVERFLOW); 1788 1789 while (uio->uio_resid > 0) { 1790 if ((bytesinfile = ip->i_size - uio->uio_offset) <= 0) 1791 break; 1792 lbn = lblkno(fs, uio->uio_offset); 1793 size = blksize(fs, ip, lbn); 1794 blkoffset = blkoff(fs, uio->uio_offset); 1795 1796 xfersize = fs->e2fs_fsize - blkoffset; 1797 xfersize = MIN(xfersize, uio->uio_resid); 1798 xfersize = MIN(xfersize, bytesinfile); 1799 1800 /* get block from ext4 extent cache */ 1801 cache_type = ext4_ext_in_cache(ip, lbn, &nex); 1802 switch (cache_type) { 1803 case EXT4_EXT_CACHE_NO: 1804 ext4_ext_find_extent(fs, ip, lbn, &path); 1805 if (path.ep_is_sparse) 1806 ep = &path.ep_sparse_ext; 1807 else 1808 ep = path.ep_ext; 1809 if (ep == NULL) 1810 return (EIO); 1811 1812 ext4_ext_put_cache(ip, ep, 1813 path.ep_is_sparse ? EXT4_EXT_CACHE_GAP : EXT4_EXT_CACHE_IN); 1814 1815 newblk = lbn - ep->e_blk + (ep->e_start_lo | 1816 (daddr_t)ep->e_start_hi << 32); 1817 1818 if (path.ep_bp != NULL) { 1819 brelse(path.ep_bp); 1820 path.ep_bp = NULL; 1821 } 1822 break; 1823 1824 case EXT4_EXT_CACHE_GAP: 1825 /* block has not been allocated yet */ 1826 break; 1827 1828 case EXT4_EXT_CACHE_IN: 1829 newblk = lbn - nex.e_blk + (nex.e_start_lo | 1830 (daddr_t)nex.e_start_hi << 32); 1831 break; 1832 1833 default: 1834 panic("%s: invalid cache type", __func__); 1835 } 1836 1837 if (cache_type == EXT4_EXT_CACHE_GAP || 1838 (cache_type == EXT4_EXT_CACHE_NO && path.ep_is_sparse)) { 1839 if (xfersize > sizeof(zeroes)) 1840 xfersize = sizeof(zeroes); 1841 error = uiomove(zeroes, xfersize, uio); 1842 if (error) 1843 return (error); 1844 } else { 1845 error = bread(ip->i_devvp, fsbtodb(fs, newblk), size, 1846 NOCRED, &bp); 1847 if (error) { 1848 brelse(bp); 1849 return (error); 1850 } 1851 1852 size -= bp->b_resid; 1853 if (size < xfersize) { 1854 if (size == 0) { 1855 bqrelse(bp); 1856 break; 1857 } 1858 xfersize = size; 1859 } 1860 error = uiomove(bp->b_data + blkoffset, xfersize, uio); 1861 bqrelse(bp); 1862 if (error) 1863 return (error); 1864 } 1865 } 1866 1867 return (0); 1868 } 1869 1870 /* 1871 * Vnode op for writing. 1872 */ 1873 static int 1874 ext2_write(struct vop_write_args *ap) 1875 { 1876 struct vnode *vp; 1877 struct uio *uio; 1878 struct inode *ip; 1879 struct m_ext2fs *fs; 1880 struct buf *bp; 1881 daddr_t lbn; 1882 off_t osize; 1883 int blkoffset, error, flags, ioflag, resid, size, seqcount, xfersize; 1884 1885 ioflag = ap->a_ioflag; 1886 uio = ap->a_uio; 1887 vp = ap->a_vp; 1888 1889 seqcount = ioflag >> IO_SEQSHIFT; 1890 ip = VTOI(vp); 1891 1892 #ifdef INVARIANTS 1893 if (uio->uio_rw != UIO_WRITE) 1894 panic("%s: mode", "ext2_write"); 1895 #endif 1896 1897 switch (vp->v_type) { 1898 case VREG: 1899 if (ioflag & IO_APPEND) 1900 uio->uio_offset = ip->i_size; 1901 if ((ip->i_flags & APPEND) && uio->uio_offset != ip->i_size) 1902 return (EPERM); 1903 /* FALLTHROUGH */ 1904 case VLNK: 1905 break; 1906 case VDIR: 1907 /* XXX differs from ffs -- this is called from ext2_mkdir(). */ 1908 if ((ioflag & IO_SYNC) == 0) 1909 panic("ext2_write: nonsync dir write"); 1910 break; 1911 default: 1912 panic("ext2_write: type %p %d (%jd,%jd)", (void *)vp, 1913 vp->v_type, (intmax_t)uio->uio_offset, 1914 (intmax_t)uio->uio_resid); 1915 } 1916 1917 KASSERT(uio->uio_resid >= 0, ("ext2_write: uio->uio_resid < 0")); 1918 KASSERT(uio->uio_offset >= 0, ("ext2_write: uio->uio_offset < 0")); 1919 fs = ip->i_e2fs; 1920 if ((uoff_t)uio->uio_offset + uio->uio_resid > fs->e2fs_maxfilesize) 1921 return (EFBIG); 1922 /* 1923 * Maybe this should be above the vnode op call, but so long as 1924 * file servers have no limits, I don't think it matters. 1925 */ 1926 if (vn_rlimit_fsize(vp, uio, uio->uio_td)) 1927 return (EFBIG); 1928 1929 resid = uio->uio_resid; 1930 osize = ip->i_size; 1931 if (seqcount > BA_SEQMAX) 1932 flags = BA_SEQMAX << BA_SEQSHIFT; 1933 else 1934 flags = seqcount << BA_SEQSHIFT; 1935 if ((ioflag & IO_SYNC) && !DOINGASYNC(vp)) 1936 flags |= IO_SYNC; 1937 1938 for (error = 0; uio->uio_resid > 0;) { 1939 lbn = lblkno(fs, uio->uio_offset); 1940 blkoffset = blkoff(fs, uio->uio_offset); 1941 xfersize = fs->e2fs_fsize - blkoffset; 1942 if (uio->uio_resid < xfersize) 1943 xfersize = uio->uio_resid; 1944 if (uio->uio_offset + xfersize > ip->i_size) 1945 vnode_pager_setsize(vp, uio->uio_offset + xfersize); 1946 1947 /* 1948 * We must perform a read-before-write if the transfer size 1949 * does not cover the entire buffer. 1950 */ 1951 if (fs->e2fs_bsize > xfersize) 1952 flags |= BA_CLRBUF; 1953 else 1954 flags &= ~BA_CLRBUF; 1955 error = ext2_balloc(ip, lbn, blkoffset + xfersize, 1956 ap->a_cred, &bp, flags); 1957 if (error != 0) 1958 break; 1959 1960 if ((ioflag & (IO_SYNC | IO_INVAL)) == (IO_SYNC | IO_INVAL)) 1961 bp->b_flags |= B_NOCACHE; 1962 if (uio->uio_offset + xfersize > ip->i_size) 1963 ip->i_size = uio->uio_offset + xfersize; 1964 size = blksize(fs, ip, lbn) - bp->b_resid; 1965 if (size < xfersize) 1966 xfersize = size; 1967 1968 error = 1969 uiomove((char *)bp->b_data + blkoffset, (int)xfersize, uio); 1970 /* 1971 * If the buffer is not already filled and we encounter an 1972 * error while trying to fill it, we have to clear out any 1973 * garbage data from the pages instantiated for the buffer. 1974 * If we do not, a failed uiomove() during a write can leave 1975 * the prior contents of the pages exposed to a userland mmap. 1976 * 1977 * Note that we need only clear buffers with a transfer size 1978 * equal to the block size because buffers with a shorter 1979 * transfer size were cleared above by the call to ext2_balloc() 1980 * with the BA_CLRBUF flag set. 1981 * 1982 * If the source region for uiomove identically mmaps the 1983 * buffer, uiomove() performed the NOP copy, and the buffer 1984 * content remains valid because the page fault handler 1985 * validated the pages. 1986 */ 1987 if (error != 0 && (bp->b_flags & B_CACHE) == 0 && 1988 fs->e2fs_bsize == xfersize) 1989 vfs_bio_clrbuf(bp); 1990 1991 vfs_bio_set_flags(bp, ioflag); 1992 1993 /* 1994 * If IO_SYNC each buffer is written synchronously. Otherwise 1995 * if we have a severe page deficiency write the buffer 1996 * asynchronously. Otherwise try to cluster, and if that 1997 * doesn't do it then either do an async write (if O_DIRECT), 1998 * or a delayed write (if not). 1999 */ 2000 if (ioflag & IO_SYNC) { 2001 (void)bwrite(bp); 2002 } else if (vm_page_count_severe() || 2003 buf_dirty_count_severe() || 2004 (ioflag & IO_ASYNC)) { 2005 bp->b_flags |= B_CLUSTEROK; 2006 bawrite(bp); 2007 } else if (xfersize + blkoffset == fs->e2fs_fsize) { 2008 if ((vp->v_mount->mnt_flag & MNT_NOCLUSTERW) == 0) { 2009 bp->b_flags |= B_CLUSTEROK; 2010 cluster_write(vp, bp, ip->i_size, seqcount, 0); 2011 } else { 2012 bawrite(bp); 2013 } 2014 } else if (ioflag & IO_DIRECT) { 2015 bp->b_flags |= B_CLUSTEROK; 2016 bawrite(bp); 2017 } else { 2018 bp->b_flags |= B_CLUSTEROK; 2019 bdwrite(bp); 2020 } 2021 if (error || xfersize == 0) 2022 break; 2023 } 2024 /* 2025 * If we successfully wrote any data, and we are not the superuser 2026 * we clear the setuid and setgid bits as a precaution against 2027 * tampering. 2028 */ 2029 if ((ip->i_mode & (ISUID | ISGID)) && resid > uio->uio_resid && 2030 ap->a_cred) { 2031 if (priv_check_cred(ap->a_cred, PRIV_VFS_RETAINSUGID, 0)) 2032 ip->i_mode &= ~(ISUID | ISGID); 2033 } 2034 if (error) { 2035 if (ioflag & IO_UNIT) { 2036 (void)ext2_truncate(vp, osize, 2037 ioflag & IO_SYNC, ap->a_cred, uio->uio_td); 2038 uio->uio_offset -= resid - uio->uio_resid; 2039 uio->uio_resid = resid; 2040 } 2041 } 2042 if (uio->uio_resid != resid) { 2043 ip->i_flag |= IN_CHANGE | IN_UPDATE; 2044 if (ioflag & IO_SYNC) 2045 error = ext2_update(vp, 1); 2046 } 2047 return (error); 2048 } 2049