1 /* 2 * Copyright (c) 1982, 1986, 1989, 1993 3 * The Regents of the University of California. All rights reserved. 4 * (c) UNIX System Laboratories, Inc. 5 * All or some portions of this file are derived from material licensed 6 * to the University of California by American Telephone and Telegraph 7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with 8 * the permission of UNIX System Laboratories, Inc. 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 the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)vfs_vnops.c 8.2 (Berkeley) 1/21/94 39 * $FreeBSD: src/sys/kern/vfs_vnops.c,v 1.87.2.13 2002/12/29 18:19:53 dillon Exp $ 40 * $DragonFly: src/sys/kern/vfs_vnops.c,v 1.58 2008/06/28 17:59:49 dillon Exp $ 41 */ 42 43 #include <sys/param.h> 44 #include <sys/systm.h> 45 #include <sys/fcntl.h> 46 #include <sys/file.h> 47 #include <sys/stat.h> 48 #include <sys/proc.h> 49 #include <sys/mount.h> 50 #include <sys/nlookup.h> 51 #include <sys/vnode.h> 52 #include <sys/buf.h> 53 #include <sys/filio.h> 54 #include <sys/ttycom.h> 55 #include <sys/conf.h> 56 #include <sys/syslog.h> 57 58 static int vn_closefile (struct file *fp); 59 static int vn_ioctl (struct file *fp, u_long com, caddr_t data, 60 struct ucred *cred); 61 static int vn_read (struct file *fp, struct uio *uio, 62 struct ucred *cred, int flags); 63 static int svn_read (struct file *fp, struct uio *uio, 64 struct ucred *cred, int flags); 65 static int vn_poll (struct file *fp, int events, struct ucred *cred); 66 static int vn_kqfilter (struct file *fp, struct knote *kn); 67 static int vn_statfile (struct file *fp, struct stat *sb, struct ucred *cred); 68 static int vn_write (struct file *fp, struct uio *uio, 69 struct ucred *cred, int flags); 70 static int svn_write (struct file *fp, struct uio *uio, 71 struct ucred *cred, int flags); 72 73 struct fileops vnode_fileops = { 74 .fo_read = vn_read, 75 .fo_write = vn_write, 76 .fo_ioctl = vn_ioctl, 77 .fo_poll = vn_poll, 78 .fo_kqfilter = vn_kqfilter, 79 .fo_stat = vn_statfile, 80 .fo_close = vn_closefile, 81 .fo_shutdown = nofo_shutdown 82 }; 83 84 struct fileops specvnode_fileops = { 85 .fo_read = svn_read, 86 .fo_write = svn_write, 87 .fo_ioctl = vn_ioctl, 88 .fo_poll = vn_poll, 89 .fo_kqfilter = vn_kqfilter, 90 .fo_stat = vn_statfile, 91 .fo_close = vn_closefile, 92 .fo_shutdown = nofo_shutdown 93 }; 94 95 /* 96 * Shortcut the device read/write. This avoids a lot of vnode junk. 97 * Basically the specfs vnops for read and write take the locked vnode, 98 * unlock it (because we can't hold the vnode locked while reading or writing 99 * a device which may block indefinitely), issues the device operation, then 100 * relock the vnode before returning, plus other junk. This bypasses all 101 * of that and just does the device operation. 102 */ 103 void 104 vn_setspecops(struct file *fp) 105 { 106 if (vfs_fastdev && fp->f_ops == &vnode_fileops) { 107 fp->f_ops = &specvnode_fileops; 108 } 109 } 110 111 /* 112 * Common code for vnode open operations. Check permissions, and call 113 * the VOP_NOPEN or VOP_NCREATE routine. 114 * 115 * The caller is responsible for setting up nd with nlookup_init() and 116 * for cleaning it up with nlookup_done(), whether we return an error 117 * or not. 118 * 119 * On success nd->nl_open_vp will hold a referenced and, if requested, 120 * locked vnode. A locked vnode is requested via NLC_LOCKVP. If fp 121 * is non-NULL the vnode will be installed in the file pointer. 122 * 123 * NOTE: The vnode is referenced just once on return whether or not it 124 * is also installed in the file pointer. 125 */ 126 int 127 vn_open(struct nlookupdata *nd, struct file *fp, int fmode, int cmode) 128 { 129 struct vnode *vp; 130 struct ucred *cred = nd->nl_cred; 131 struct vattr vat; 132 struct vattr *vap = &vat; 133 int mode, error; 134 135 /* 136 * Lookup the path and create or obtain the vnode. After a 137 * successful lookup a locked nd->nl_nch will be returned. 138 * 139 * The result of this section should be a locked vnode. 140 * 141 * XXX with only a little work we should be able to avoid locking 142 * the vnode if FWRITE, O_CREAT, and O_TRUNC are *not* set. 143 */ 144 if (fmode & O_CREAT) { 145 /* 146 * CONDITIONAL CREATE FILE CASE 147 * 148 * Setting NLC_CREATE causes a negative hit to store 149 * the negative hit ncp and not return an error. Then 150 * nc_error or nc_vp may be checked to see if the ncp 151 * represents a negative hit. NLC_CREATE also requires 152 * write permission on the governing directory or EPERM 153 * is returned. 154 */ 155 if ((fmode & O_EXCL) == 0 && (fmode & O_NOFOLLOW) == 0) 156 nd->nl_flags |= NLC_FOLLOW; 157 nd->nl_flags |= NLC_CREATE; 158 nd->nl_flags |= NLC_REFDVP; 159 bwillinode(1); 160 error = nlookup(nd); 161 } else { 162 /* 163 * NORMAL OPEN FILE CASE 164 */ 165 error = nlookup(nd); 166 } 167 168 if (error) 169 return (error); 170 171 /* 172 * split case to allow us to re-resolve and retry the ncp in case 173 * we get ESTALE. 174 */ 175 again: 176 if (fmode & O_CREAT) { 177 if (nd->nl_nch.ncp->nc_vp == NULL) { 178 if ((error = ncp_writechk(&nd->nl_nch)) != 0) 179 return (error); 180 VATTR_NULL(vap); 181 vap->va_type = VREG; 182 vap->va_mode = cmode; 183 if (fmode & O_EXCL) 184 vap->va_vaflags |= VA_EXCLUSIVE; 185 error = VOP_NCREATE(&nd->nl_nch, nd->nl_dvp, &vp, 186 nd->nl_cred, vap); 187 if (error) 188 return (error); 189 fmode &= ~O_TRUNC; 190 /* locked vnode is returned */ 191 } else { 192 if (fmode & O_EXCL) { 193 error = EEXIST; 194 } else { 195 error = cache_vget(&nd->nl_nch, cred, 196 LK_EXCLUSIVE, &vp); 197 } 198 if (error) 199 return (error); 200 fmode &= ~O_CREAT; 201 } 202 } else { 203 error = cache_vget(&nd->nl_nch, cred, LK_EXCLUSIVE, &vp); 204 if (error) 205 return (error); 206 } 207 208 /* 209 * We have a locked vnode and ncp now. Note that the ncp will 210 * be cleaned up by the caller if nd->nl_nch is left intact. 211 */ 212 if (vp->v_type == VLNK) { 213 error = EMLINK; 214 goto bad; 215 } 216 if (vp->v_type == VSOCK) { 217 error = EOPNOTSUPP; 218 goto bad; 219 } 220 if ((fmode & O_CREAT) == 0) { 221 mode = 0; 222 if (fmode & (FWRITE | O_TRUNC)) { 223 if (vp->v_type == VDIR) { 224 error = EISDIR; 225 goto bad; 226 } 227 error = vn_writechk(vp, &nd->nl_nch); 228 if (error) { 229 /* 230 * Special stale handling, re-resolve the 231 * vnode. 232 */ 233 if (error == ESTALE) { 234 vput(vp); 235 vp = NULL; 236 cache_setunresolved(&nd->nl_nch); 237 error = cache_resolve(&nd->nl_nch, cred); 238 if (error == 0) 239 goto again; 240 } 241 goto bad; 242 } 243 mode |= VWRITE; 244 } 245 if (fmode & FREAD) 246 mode |= VREAD; 247 if (mode) { 248 error = VOP_ACCESS(vp, mode, cred); 249 if (error) { 250 /* 251 * Special stale handling, re-resolve the 252 * vnode. 253 */ 254 if (error == ESTALE) { 255 vput(vp); 256 vp = NULL; 257 cache_setunresolved(&nd->nl_nch); 258 error = cache_resolve(&nd->nl_nch, cred); 259 if (error == 0) 260 goto again; 261 } 262 goto bad; 263 } 264 } 265 } 266 if (fmode & O_TRUNC) { 267 vn_unlock(vp); /* XXX */ 268 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); /* XXX */ 269 VATTR_NULL(vap); 270 vap->va_size = 0; 271 error = VOP_SETATTR(vp, vap, cred); 272 if (error) 273 goto bad; 274 } 275 276 /* 277 * Setup the fp so VOP_OPEN can override it. No descriptor has been 278 * associated with the fp yet so we own it clean. 279 * 280 * f_nchandle inherits nl_nch. This used to be necessary only for 281 * directories but now we do it unconditionally so f*() ops 282 * such as fchmod() can access the actual namespace that was 283 * used to open the file. 284 */ 285 if (fp) { 286 fp->f_nchandle = nd->nl_nch; 287 cache_zero(&nd->nl_nch); 288 cache_unlock(&fp->f_nchandle); 289 } 290 291 /* 292 * Get rid of nl_nch. vn_open does not return it (it returns the 293 * vnode or the file pointer). Note: we can't leave nl_nch locked 294 * through the VOP_OPEN anyway since the VOP_OPEN may block, e.g. 295 * on /dev/ttyd0 296 */ 297 if (nd->nl_nch.ncp) 298 cache_put(&nd->nl_nch); 299 300 error = VOP_OPEN(vp, fmode, cred, fp); 301 if (error) { 302 /* 303 * setting f_ops to &badfileops will prevent the descriptor 304 * code from trying to close and release the vnode, since 305 * the open failed we do not want to call close. 306 */ 307 if (fp) { 308 fp->f_data = NULL; 309 fp->f_ops = &badfileops; 310 } 311 goto bad; 312 } 313 314 #if 0 315 /* 316 * Assert that VREG files have been setup for vmio. 317 */ 318 KASSERT(vp->v_type != VREG || vp->v_object != NULL, 319 ("vn_open: regular file was not VMIO enabled!")); 320 #endif 321 322 /* 323 * Return the vnode. XXX needs some cleaning up. The vnode is 324 * only returned in the fp == NULL case. 325 */ 326 if (fp == NULL) { 327 nd->nl_open_vp = vp; 328 nd->nl_vp_fmode = fmode; 329 if ((nd->nl_flags & NLC_LOCKVP) == 0) 330 vn_unlock(vp); 331 } else { 332 vput(vp); 333 } 334 return (0); 335 bad: 336 if (vp) 337 vput(vp); 338 return (error); 339 } 340 341 int 342 vn_opendisk(const char *devname, int fmode, struct vnode **vpp) 343 { 344 struct vnode *vp; 345 int error; 346 347 if (strncmp(devname, "/dev/", 5) == 0) 348 devname += 5; 349 if ((vp = getsynthvnode(devname)) == NULL) { 350 error = ENODEV; 351 } else { 352 error = VOP_OPEN(vp, fmode, proc0.p_ucred, NULL); 353 vn_unlock(vp); 354 if (error) { 355 vrele(vp); 356 vp = NULL; 357 } 358 } 359 *vpp = vp; 360 return (error); 361 } 362 363 /* 364 * Check for write permissions on the specified vnode. nch may be NULL. 365 */ 366 int 367 vn_writechk(struct vnode *vp, struct nchandle *nch) 368 { 369 /* 370 * If there's shared text associated with 371 * the vnode, try to free it up once. If 372 * we fail, we can't allow writing. 373 */ 374 if (vp->v_flag & VTEXT) 375 return (ETXTBSY); 376 377 /* 378 * If the vnode represents a regular file, check the mount 379 * point via the nch. This may be a different mount point 380 * then the one embedded in the vnode (e.g. nullfs). 381 * 382 * We can still write to non-regular files (e.g. devices) 383 * via read-only mounts. 384 */ 385 if (nch && nch->ncp && vp->v_type == VREG) 386 return (ncp_writechk(nch)); 387 return (0); 388 } 389 390 /* 391 * Check whether the underlying mount is read-only. The mount point 392 * referenced by the namecache may be different from the mount point 393 * used by the underlying vnode in the case of NULLFS, so a separate 394 * check is needed. 395 */ 396 int 397 ncp_writechk(struct nchandle *nch) 398 { 399 if (nch->mount && (nch->mount->mnt_flag & MNT_RDONLY)) 400 return (EROFS); 401 return(0); 402 } 403 404 /* 405 * Vnode close call 406 */ 407 int 408 vn_close(struct vnode *vp, int flags) 409 { 410 int error; 411 412 if ((error = vn_lock(vp, LK_EXCLUSIVE | LK_RETRY)) == 0) { 413 error = VOP_CLOSE(vp, flags); 414 vn_unlock(vp); 415 } 416 vrele(vp); 417 return (error); 418 } 419 420 static __inline 421 int 422 sequential_heuristic(struct uio *uio, struct file *fp) 423 { 424 /* 425 * Sequential heuristic - detect sequential operation 426 */ 427 if ((uio->uio_offset == 0 && fp->f_seqcount > 0) || 428 uio->uio_offset == fp->f_nextoff) { 429 int tmpseq = fp->f_seqcount; 430 /* 431 * XXX we assume that the filesystem block size is 432 * the default. Not true, but still gives us a pretty 433 * good indicator of how sequential the read operations 434 * are. 435 */ 436 tmpseq += (uio->uio_resid + BKVASIZE - 1) / BKVASIZE; 437 if (tmpseq > IO_SEQMAX) 438 tmpseq = IO_SEQMAX; 439 fp->f_seqcount = tmpseq; 440 return(fp->f_seqcount << IO_SEQSHIFT); 441 } 442 443 /* 444 * Not sequential, quick draw-down of seqcount 445 */ 446 if (fp->f_seqcount > 1) 447 fp->f_seqcount = 1; 448 else 449 fp->f_seqcount = 0; 450 return(0); 451 } 452 453 /* 454 * Package up an I/O request on a vnode into a uio and do it. 455 */ 456 int 457 vn_rdwr(enum uio_rw rw, struct vnode *vp, caddr_t base, int len, 458 off_t offset, enum uio_seg segflg, int ioflg, 459 struct ucred *cred, int *aresid) 460 { 461 struct uio auio; 462 struct iovec aiov; 463 struct ccms_lock ccms_lock; 464 int error; 465 466 if ((ioflg & IO_NODELOCKED) == 0) 467 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 468 auio.uio_iov = &aiov; 469 auio.uio_iovcnt = 1; 470 aiov.iov_base = base; 471 aiov.iov_len = len; 472 auio.uio_resid = len; 473 auio.uio_offset = offset; 474 auio.uio_segflg = segflg; 475 auio.uio_rw = rw; 476 auio.uio_td = curthread; 477 ccms_lock_get_uio(&vp->v_ccms, &ccms_lock, &auio); 478 if (rw == UIO_READ) { 479 error = VOP_READ(vp, &auio, ioflg, cred); 480 } else { 481 error = VOP_WRITE(vp, &auio, ioflg, cred); 482 } 483 ccms_lock_put(&vp->v_ccms, &ccms_lock); 484 if (aresid) 485 *aresid = auio.uio_resid; 486 else 487 if (auio.uio_resid && error == 0) 488 error = EIO; 489 if ((ioflg & IO_NODELOCKED) == 0) 490 vn_unlock(vp); 491 return (error); 492 } 493 494 /* 495 * Package up an I/O request on a vnode into a uio and do it. The I/O 496 * request is split up into smaller chunks and we try to avoid saturating 497 * the buffer cache while potentially holding a vnode locked, so we 498 * check bwillwrite() before calling vn_rdwr(). We also call uio_yield() 499 * to give other processes a chance to lock the vnode (either other processes 500 * core'ing the same binary, or unrelated processes scanning the directory). 501 */ 502 int 503 vn_rdwr_inchunks(enum uio_rw rw, struct vnode *vp, caddr_t base, int len, 504 off_t offset, enum uio_seg segflg, int ioflg, 505 struct ucred *cred, int *aresid) 506 { 507 int error = 0; 508 509 do { 510 int chunk; 511 512 /* 513 * Force `offset' to a multiple of MAXBSIZE except possibly 514 * for the first chunk, so that filesystems only need to 515 * write full blocks except possibly for the first and last 516 * chunks. 517 */ 518 chunk = MAXBSIZE - (uoff_t)offset % MAXBSIZE; 519 520 if (chunk > len) 521 chunk = len; 522 if (vp->v_type == VREG) { 523 switch(rw) { 524 case UIO_READ: 525 bwillread(chunk); 526 break; 527 case UIO_WRITE: 528 bwillwrite(chunk); 529 break; 530 } 531 } 532 error = vn_rdwr(rw, vp, base, chunk, offset, segflg, 533 ioflg, cred, aresid); 534 len -= chunk; /* aresid calc already includes length */ 535 if (error) 536 break; 537 offset += chunk; 538 base += chunk; 539 uio_yield(); 540 } while (len); 541 if (aresid) 542 *aresid += len; 543 return (error); 544 } 545 546 /* 547 * MPALMOSTSAFE - acquires mplock 548 */ 549 static int 550 vn_read(struct file *fp, struct uio *uio, struct ucred *cred, int flags) 551 { 552 struct ccms_lock ccms_lock; 553 struct vnode *vp; 554 int error, ioflag; 555 556 get_mplock(); 557 KASSERT(uio->uio_td == curthread, 558 ("uio_td %p is not td %p", uio->uio_td, curthread)); 559 vp = (struct vnode *)fp->f_data; 560 561 ioflag = 0; 562 if (flags & O_FBLOCKING) { 563 /* ioflag &= ~IO_NDELAY; */ 564 } else if (flags & O_FNONBLOCKING) { 565 ioflag |= IO_NDELAY; 566 } else if (fp->f_flag & FNONBLOCK) { 567 ioflag |= IO_NDELAY; 568 } 569 if (flags & O_FBUFFERED) { 570 /* ioflag &= ~IO_DIRECT; */ 571 } else if (flags & O_FUNBUFFERED) { 572 ioflag |= IO_DIRECT; 573 } else if (fp->f_flag & O_DIRECT) { 574 ioflag |= IO_DIRECT; 575 } 576 vn_lock(vp, LK_SHARED | LK_RETRY); 577 if ((flags & O_FOFFSET) == 0) 578 uio->uio_offset = fp->f_offset; 579 ioflag |= sequential_heuristic(uio, fp); 580 581 ccms_lock_get_uio(&vp->v_ccms, &ccms_lock, uio); 582 error = VOP_READ(vp, uio, ioflag, cred); 583 ccms_lock_put(&vp->v_ccms, &ccms_lock); 584 if ((flags & O_FOFFSET) == 0) 585 fp->f_offset = uio->uio_offset; 586 fp->f_nextoff = uio->uio_offset; 587 vn_unlock(vp); 588 rel_mplock(); 589 return (error); 590 } 591 592 /* 593 * Device-optimized file table vnode read routine. 594 * 595 * This bypasses the VOP table and talks directly to the device. Most 596 * filesystems just route to specfs and can make this optimization. 597 * 598 * MPALMOSTSAFE - acquires mplock 599 */ 600 static int 601 svn_read(struct file *fp, struct uio *uio, struct ucred *cred, int flags) 602 { 603 struct vnode *vp; 604 int ioflag; 605 int error; 606 cdev_t dev; 607 608 get_mplock(); 609 KASSERT(uio->uio_td == curthread, 610 ("uio_td %p is not td %p", uio->uio_td, curthread)); 611 612 vp = (struct vnode *)fp->f_data; 613 if (vp == NULL || vp->v_type == VBAD) { 614 error = EBADF; 615 goto done; 616 } 617 618 if ((dev = vp->v_rdev) == NULL) { 619 error = EBADF; 620 goto done; 621 } 622 reference_dev(dev); 623 624 if (uio->uio_resid == 0) { 625 error = 0; 626 goto done; 627 } 628 if ((flags & O_FOFFSET) == 0) 629 uio->uio_offset = fp->f_offset; 630 631 ioflag = 0; 632 if (flags & O_FBLOCKING) { 633 /* ioflag &= ~IO_NDELAY; */ 634 } else if (flags & O_FNONBLOCKING) { 635 ioflag |= IO_NDELAY; 636 } else if (fp->f_flag & FNONBLOCK) { 637 ioflag |= IO_NDELAY; 638 } 639 if (flags & O_FBUFFERED) { 640 /* ioflag &= ~IO_DIRECT; */ 641 } else if (flags & O_FUNBUFFERED) { 642 ioflag |= IO_DIRECT; 643 } else if (fp->f_flag & O_DIRECT) { 644 ioflag |= IO_DIRECT; 645 } 646 ioflag |= sequential_heuristic(uio, fp); 647 648 error = dev_dread(dev, uio, ioflag); 649 650 release_dev(dev); 651 if ((flags & O_FOFFSET) == 0) 652 fp->f_offset = uio->uio_offset; 653 fp->f_nextoff = uio->uio_offset; 654 done: 655 rel_mplock(); 656 return (error); 657 } 658 659 /* 660 * MPALMOSTSAFE - acquires mplock 661 */ 662 static int 663 vn_write(struct file *fp, struct uio *uio, struct ucred *cred, int flags) 664 { 665 struct ccms_lock ccms_lock; 666 struct vnode *vp; 667 int error, ioflag; 668 669 get_mplock(); 670 KASSERT(uio->uio_td == curthread, 671 ("uio_td %p is not p %p", uio->uio_td, curthread)); 672 vp = (struct vnode *)fp->f_data; 673 #if 0 674 /* VOP_WRITE should handle this now */ 675 if (vp->v_type == VREG || vp->v_type == VDATABASE) 676 bwillwrite(); 677 #endif 678 vp = (struct vnode *)fp->f_data; /* XXX needed? */ 679 680 ioflag = IO_UNIT; 681 if (vp->v_type == VREG && 682 ((fp->f_flag & O_APPEND) || (flags & O_FAPPEND))) { 683 ioflag |= IO_APPEND; 684 } 685 686 if (flags & O_FBLOCKING) { 687 /* ioflag &= ~IO_NDELAY; */ 688 } else if (flags & O_FNONBLOCKING) { 689 ioflag |= IO_NDELAY; 690 } else if (fp->f_flag & FNONBLOCK) { 691 ioflag |= IO_NDELAY; 692 } 693 if (flags & O_FBUFFERED) { 694 /* ioflag &= ~IO_DIRECT; */ 695 } else if (flags & O_FUNBUFFERED) { 696 ioflag |= IO_DIRECT; 697 } else if (fp->f_flag & O_DIRECT) { 698 ioflag |= IO_DIRECT; 699 } 700 if (flags & O_FASYNCWRITE) { 701 /* ioflag &= ~IO_SYNC; */ 702 } else if (flags & O_FSYNCWRITE) { 703 ioflag |= IO_SYNC; 704 } else if (fp->f_flag & O_FSYNC) { 705 ioflag |= IO_SYNC; 706 } 707 708 if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)) 709 ioflag |= IO_SYNC; 710 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 711 if ((flags & O_FOFFSET) == 0) 712 uio->uio_offset = fp->f_offset; 713 ioflag |= sequential_heuristic(uio, fp); 714 ccms_lock_get_uio(&vp->v_ccms, &ccms_lock, uio); 715 error = VOP_WRITE(vp, uio, ioflag, cred); 716 ccms_lock_put(&vp->v_ccms, &ccms_lock); 717 if ((flags & O_FOFFSET) == 0) 718 fp->f_offset = uio->uio_offset; 719 fp->f_nextoff = uio->uio_offset; 720 vn_unlock(vp); 721 rel_mplock(); 722 return (error); 723 } 724 725 /* 726 * Device-optimized file table vnode write routine. 727 * 728 * This bypasses the VOP table and talks directly to the device. Most 729 * filesystems just route to specfs and can make this optimization. 730 * 731 * MPALMOSTSAFE - acquires mplock 732 */ 733 static int 734 svn_write(struct file *fp, struct uio *uio, struct ucred *cred, int flags) 735 { 736 struct vnode *vp; 737 int ioflag; 738 int error; 739 cdev_t dev; 740 741 get_mplock(); 742 KASSERT(uio->uio_td == curthread, 743 ("uio_td %p is not p %p", uio->uio_td, curthread)); 744 745 vp = (struct vnode *)fp->f_data; 746 if (vp == NULL || vp->v_type == VBAD) { 747 error = EBADF; 748 goto done; 749 } 750 if (vp->v_type == VREG) 751 bwillwrite(uio->uio_resid); 752 vp = (struct vnode *)fp->f_data; /* XXX needed? */ 753 754 if ((dev = vp->v_rdev) == NULL) { 755 error = EBADF; 756 goto done; 757 } 758 reference_dev(dev); 759 760 if ((flags & O_FOFFSET) == 0) 761 uio->uio_offset = fp->f_offset; 762 763 ioflag = IO_UNIT; 764 if (vp->v_type == VREG && 765 ((fp->f_flag & O_APPEND) || (flags & O_FAPPEND))) { 766 ioflag |= IO_APPEND; 767 } 768 769 if (flags & O_FBLOCKING) { 770 /* ioflag &= ~IO_NDELAY; */ 771 } else if (flags & O_FNONBLOCKING) { 772 ioflag |= IO_NDELAY; 773 } else if (fp->f_flag & FNONBLOCK) { 774 ioflag |= IO_NDELAY; 775 } 776 if (flags & O_FBUFFERED) { 777 /* ioflag &= ~IO_DIRECT; */ 778 } else if (flags & O_FUNBUFFERED) { 779 ioflag |= IO_DIRECT; 780 } else if (fp->f_flag & O_DIRECT) { 781 ioflag |= IO_DIRECT; 782 } 783 if (flags & O_FASYNCWRITE) { 784 /* ioflag &= ~IO_SYNC; */ 785 } else if (flags & O_FSYNCWRITE) { 786 ioflag |= IO_SYNC; 787 } else if (fp->f_flag & O_FSYNC) { 788 ioflag |= IO_SYNC; 789 } 790 791 if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)) 792 ioflag |= IO_SYNC; 793 ioflag |= sequential_heuristic(uio, fp); 794 795 error = dev_dwrite(dev, uio, ioflag); 796 797 release_dev(dev); 798 if ((flags & O_FOFFSET) == 0) 799 fp->f_offset = uio->uio_offset; 800 fp->f_nextoff = uio->uio_offset; 801 done: 802 rel_mplock(); 803 return (error); 804 } 805 806 /* 807 * MPALMOSTSAFE - acquires mplock 808 */ 809 static int 810 vn_statfile(struct file *fp, struct stat *sb, struct ucred *cred) 811 { 812 struct vnode *vp; 813 int error; 814 815 get_mplock(); 816 vp = (struct vnode *)fp->f_data; 817 error = vn_stat(vp, sb, cred); 818 rel_mplock(); 819 return (error); 820 } 821 822 int 823 vn_stat(struct vnode *vp, struct stat *sb, struct ucred *cred) 824 { 825 struct vattr vattr; 826 struct vattr *vap; 827 int error; 828 u_short mode; 829 cdev_t dev; 830 831 vap = &vattr; 832 error = VOP_GETATTR(vp, vap); 833 if (error) 834 return (error); 835 836 /* 837 * Zero the spare stat fields 838 */ 839 sb->st_lspare = 0; 840 sb->st_qspare = 0; 841 842 /* 843 * Copy from vattr table 844 */ 845 if (vap->va_fsid != VNOVAL) 846 sb->st_dev = vap->va_fsid; 847 else 848 sb->st_dev = vp->v_mount->mnt_stat.f_fsid.val[0]; 849 sb->st_ino = vap->va_fileid; 850 mode = vap->va_mode; 851 switch (vap->va_type) { 852 case VREG: 853 mode |= S_IFREG; 854 break; 855 case VDATABASE: 856 mode |= S_IFDB; 857 break; 858 case VDIR: 859 mode |= S_IFDIR; 860 break; 861 case VBLK: 862 mode |= S_IFBLK; 863 break; 864 case VCHR: 865 mode |= S_IFCHR; 866 break; 867 case VLNK: 868 mode |= S_IFLNK; 869 /* This is a cosmetic change, symlinks do not have a mode. */ 870 if (vp->v_mount->mnt_flag & MNT_NOSYMFOLLOW) 871 sb->st_mode &= ~ACCESSPERMS; /* 0000 */ 872 else 873 sb->st_mode |= ACCESSPERMS; /* 0777 */ 874 break; 875 case VSOCK: 876 mode |= S_IFSOCK; 877 break; 878 case VFIFO: 879 mode |= S_IFIFO; 880 break; 881 default: 882 return (EBADF); 883 }; 884 sb->st_mode = mode; 885 if (vap->va_nlink > (nlink_t)-1) 886 sb->st_nlink = (nlink_t)-1; 887 else 888 sb->st_nlink = vap->va_nlink; 889 sb->st_uid = vap->va_uid; 890 sb->st_gid = vap->va_gid; 891 sb->st_rdev = makeudev(vap->va_rmajor, vap->va_rminor); 892 sb->st_size = vap->va_size; 893 sb->st_atimespec = vap->va_atime; 894 sb->st_mtimespec = vap->va_mtime; 895 sb->st_ctimespec = vap->va_ctime; 896 897 /* 898 * A VCHR and VBLK device may track the last access and last modified 899 * time independantly of the filesystem. This is particularly true 900 * because device read and write calls may bypass the filesystem. 901 */ 902 if (vp->v_type == VCHR || vp->v_type == VBLK) { 903 if ((dev = vp->v_rdev) != NULL) { 904 if (dev->si_lastread) { 905 sb->st_atimespec.tv_sec = dev->si_lastread; 906 sb->st_atimespec.tv_nsec = 0; 907 } 908 if (dev->si_lastwrite) { 909 sb->st_atimespec.tv_sec = dev->si_lastwrite; 910 sb->st_atimespec.tv_nsec = 0; 911 } 912 } 913 } 914 915 /* 916 * According to www.opengroup.org, the meaning of st_blksize is 917 * "a filesystem-specific preferred I/O block size for this 918 * object. In some filesystem types, this may vary from file 919 * to file" 920 * Default to PAGE_SIZE after much discussion. 921 */ 922 923 if (vap->va_type == VREG) { 924 sb->st_blksize = vap->va_blocksize; 925 } else if (vn_isdisk(vp, NULL)) { 926 /* 927 * XXX this is broken. If the device is not yet open (aka 928 * stat() call, aka v_rdev == NULL), how are we supposed 929 * to get a valid block size out of it? 930 */ 931 cdev_t dev; 932 933 if ((dev = vp->v_rdev) == NULL) { 934 if (vp->v_type == VCHR) 935 dev = get_dev(vp->v_umajor, vp->v_uminor); 936 } 937 sb->st_blksize = dev->si_bsize_best; 938 if (sb->st_blksize < dev->si_bsize_phys) 939 sb->st_blksize = dev->si_bsize_phys; 940 if (sb->st_blksize < BLKDEV_IOSIZE) 941 sb->st_blksize = BLKDEV_IOSIZE; 942 } else { 943 sb->st_blksize = PAGE_SIZE; 944 } 945 946 sb->st_flags = vap->va_flags; 947 if (suser_cred(cred, 0)) 948 sb->st_gen = 0; 949 else 950 sb->st_gen = (u_int32_t)vap->va_gen; 951 952 #if (S_BLKSIZE == 512) 953 /* Optimize this case */ 954 sb->st_blocks = vap->va_bytes >> 9; 955 #else 956 sb->st_blocks = vap->va_bytes / S_BLKSIZE; 957 #endif 958 sb->st_fsmid = vap->va_fsmid; 959 return (0); 960 } 961 962 /* 963 * MPALMOSTSAFE - acquires mplock 964 */ 965 static int 966 vn_ioctl(struct file *fp, u_long com, caddr_t data, struct ucred *ucred) 967 { 968 struct vnode *vp = ((struct vnode *)fp->f_data); 969 struct vnode *ovp; 970 struct vattr vattr; 971 int error; 972 973 get_mplock(); 974 975 switch (vp->v_type) { 976 case VREG: 977 case VDIR: 978 if (com == FIONREAD) { 979 if ((error = VOP_GETATTR(vp, &vattr)) != 0) 980 break; 981 *(int *)data = vattr.va_size - fp->f_offset; 982 error = 0; 983 break; 984 } 985 if (com == FIOASYNC) { /* XXX */ 986 error = 0; /* XXX */ 987 break; 988 } 989 /* fall into ... */ 990 default: 991 #if 0 992 return (ENOTTY); 993 #endif 994 case VFIFO: 995 case VCHR: 996 case VBLK: 997 if (com == FIODTYPE) { 998 if (vp->v_type != VCHR && vp->v_type != VBLK) { 999 error = ENOTTY; 1000 break; 1001 } 1002 *(int *)data = dev_dflags(vp->v_rdev) & D_TYPEMASK; 1003 error = 0; 1004 break; 1005 } 1006 error = VOP_IOCTL(vp, com, data, fp->f_flag, ucred); 1007 if (error == 0 && com == TIOCSCTTY) { 1008 struct proc *p = curthread->td_proc; 1009 struct session *sess; 1010 1011 if (p == NULL) { 1012 error = ENOTTY; 1013 break; 1014 } 1015 1016 sess = p->p_session; 1017 /* Do nothing if reassigning same control tty */ 1018 if (sess->s_ttyvp == vp) { 1019 error = 0; 1020 break; 1021 } 1022 1023 /* Get rid of reference to old control tty */ 1024 ovp = sess->s_ttyvp; 1025 vref(vp); 1026 sess->s_ttyvp = vp; 1027 if (ovp) 1028 vrele(ovp); 1029 } 1030 break; 1031 } 1032 rel_mplock(); 1033 return (error); 1034 } 1035 1036 /* 1037 * MPALMOSTSAFE - acquires mplock 1038 */ 1039 static int 1040 vn_poll(struct file *fp, int events, struct ucred *cred) 1041 { 1042 int error; 1043 1044 get_mplock(); 1045 error = VOP_POLL(((struct vnode *)fp->f_data), events, cred); 1046 rel_mplock(); 1047 return (error); 1048 } 1049 1050 /* 1051 * Check that the vnode is still valid, and if so 1052 * acquire requested lock. 1053 */ 1054 int 1055 #ifndef DEBUG_LOCKS 1056 vn_lock(struct vnode *vp, int flags) 1057 #else 1058 debug_vn_lock(struct vnode *vp, int flags, const char *filename, int line) 1059 #endif 1060 { 1061 int error; 1062 1063 do { 1064 #ifdef DEBUG_LOCKS 1065 vp->filename = filename; 1066 vp->line = line; 1067 error = debuglockmgr(&vp->v_lock, flags, 1068 "vn_lock", filename, line); 1069 #else 1070 error = lockmgr(&vp->v_lock, flags); 1071 #endif 1072 if (error == 0) 1073 break; 1074 } while (flags & LK_RETRY); 1075 1076 /* 1077 * Because we (had better!) have a ref on the vnode, once it 1078 * goes to VRECLAIMED state it will not be recycled until all 1079 * refs go away. So we can just check the flag. 1080 */ 1081 if (error == 0 && (vp->v_flag & VRECLAIMED)) { 1082 lockmgr(&vp->v_lock, LK_RELEASE); 1083 error = ENOENT; 1084 } 1085 return (error); 1086 } 1087 1088 void 1089 vn_unlock(struct vnode *vp) 1090 { 1091 lockmgr(&vp->v_lock, LK_RELEASE); 1092 } 1093 1094 int 1095 vn_islocked(struct vnode *vp) 1096 { 1097 return (lockstatus(&vp->v_lock, curthread)); 1098 } 1099 1100 /* 1101 * MPALMOSTSAFE - acquires mplock 1102 */ 1103 static int 1104 vn_closefile(struct file *fp) 1105 { 1106 int error; 1107 1108 get_mplock(); 1109 fp->f_ops = &badfileops; 1110 error = vn_close(((struct vnode *)fp->f_data), fp->f_flag); 1111 rel_mplock(); 1112 return(error); 1113 } 1114 1115 /* 1116 * MPALMOSTSAFE - acquires mplock 1117 */ 1118 static int 1119 vn_kqfilter(struct file *fp, struct knote *kn) 1120 { 1121 int error; 1122 1123 get_mplock(); 1124 error = VOP_KQFILTER(((struct vnode *)fp->f_data), kn); 1125 rel_mplock(); 1126 return (error); 1127 } 1128