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 1.48 2006/09/18 18:19:33 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 struct namecache *ncp; 134 int mode, error; 135 136 /* 137 * Lookup the path and create or obtain the vnode. After a 138 * successful lookup a locked nd->nl_ncp will be returned. 139 * 140 * The result of this section should be a locked vnode. 141 * 142 * XXX with only a little work we should be able to avoid locking 143 * the vnode if FWRITE, O_CREAT, and O_TRUNC are *not* set. 144 */ 145 if (fmode & O_CREAT) { 146 /* 147 * CONDITIONAL CREATE FILE CASE 148 * 149 * Setting NLC_CREATE causes a negative hit to store 150 * the negative hit ncp and not return an error. Then 151 * nc_error or nc_vp may be checked to see if the ncp 152 * represents a negative hit. NLC_CREATE also requires 153 * write permission on the governing directory or EPERM 154 * is returned. 155 */ 156 if ((fmode & O_EXCL) == 0 && (fmode & O_NOFOLLOW) == 0) 157 nd->nl_flags |= NLC_FOLLOW; 158 nd->nl_flags |= NLC_CREATE; 159 bwillwrite(); 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 ncp = nd->nl_ncp; 171 172 /* 173 * split case to allow us to re-resolve and retry the ncp in case 174 * we get ESTALE. 175 */ 176 again: 177 if (fmode & O_CREAT) { 178 if (ncp->nc_vp == NULL) { 179 if ((error = ncp_writechk(ncp)) != 0) 180 return (error); 181 VATTR_NULL(vap); 182 vap->va_type = VREG; 183 vap->va_mode = cmode; 184 if (fmode & O_EXCL) 185 vap->va_vaflags |= VA_EXCLUSIVE; 186 error = VOP_NCREATE(ncp, &vp, 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(ncp, cred, 196 LK_EXCLUSIVE, &vp); 197 } 198 if (error) 199 return (error); 200 fmode &= ~O_CREAT; 201 } 202 } else { 203 error = cache_vget(ncp, 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_ncp 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, ncp); 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(ncp); 237 error = cache_resolve(ncp, 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(ncp); 258 error = cache_resolve(ncp, 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_ncp inherits nl_ncp. 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_ncp = nd->nl_ncp; 287 nd->nl_ncp = NULL; 288 cache_unlock(fp->f_ncp); 289 } 290 291 /* 292 * Get rid of nl_ncp. vn_open does not return it (it returns the 293 * vnode or the file pointer). Note: we can't leave nl_ncp locked 294 * through the VOP_OPEN anyway since the VOP_OPEN may block, e.g. 295 * on /dev/ttyd0 296 */ 297 if (nd->nl_ncp) { 298 cache_put(nd->nl_ncp); 299 nd->nl_ncp = NULL; 300 } 301 302 error = VOP_OPEN(vp, fmode, cred, fp); 303 if (error) { 304 /* 305 * setting f_ops to &badfileops will prevent the descriptor 306 * code from trying to close and release the vnode, since 307 * the open failed we do not want to call close. 308 */ 309 if (fp) { 310 fp->f_data = NULL; 311 fp->f_ops = &badfileops; 312 } 313 goto bad; 314 } 315 316 #if 0 317 /* 318 * Assert that VREG files have been setup for vmio. 319 */ 320 KASSERT(vp->v_type != VREG || vp->v_object != NULL, 321 ("vn_open: regular file was not VMIO enabled!")); 322 #endif 323 324 /* 325 * Return the vnode. XXX needs some cleaning up. The vnode is 326 * only returned in the fp == NULL case. 327 */ 328 if (fp == NULL) { 329 nd->nl_open_vp = vp; 330 nd->nl_vp_fmode = fmode; 331 if ((nd->nl_flags & NLC_LOCKVP) == 0) 332 vn_unlock(vp); 333 } else { 334 vput(vp); 335 } 336 return (0); 337 bad: 338 if (vp) 339 vput(vp); 340 return (error); 341 } 342 343 /* 344 * Check for write permissions on the specified vnode. 345 */ 346 int 347 vn_writechk(struct vnode *vp, struct namecache *ncp) 348 { 349 /* 350 * If there's shared text associated with 351 * the vnode, try to free it up once. If 352 * we fail, we can't allow writing. 353 */ 354 if (vp->v_flag & VTEXT) 355 return (ETXTBSY); 356 357 /* 358 * If the vnode represents a regular file, check the mount 359 * point via the ncp. This may be a different mount point 360 * then the one embedded in the vnode (e.g. nullfs). 361 * 362 * We can still write to non-regular files (e.g. devices) 363 * via read-only mounts. 364 */ 365 if (ncp && vp->v_type == VREG) 366 return (ncp_writechk(ncp)); 367 return (0); 368 } 369 370 /* 371 * Check whether the underlying mount is read-only. The mount point 372 * referenced by the namecache may be different from the mount point 373 * used by the underlying vnode in the case of NULLFS, so a separate 374 * check is needed. 375 */ 376 int 377 ncp_writechk(struct namecache *ncp) 378 { 379 if (ncp->nc_mount && (ncp->nc_mount->mnt_flag & MNT_RDONLY)) 380 return (EROFS); 381 return(0); 382 } 383 384 /* 385 * Vnode close call 386 */ 387 int 388 vn_close(struct vnode *vp, int flags) 389 { 390 int error; 391 392 if ((error = vn_lock(vp, LK_EXCLUSIVE | LK_RETRY)) == 0) { 393 error = VOP_CLOSE(vp, flags); 394 vn_unlock(vp); 395 } 396 vrele(vp); 397 return (error); 398 } 399 400 static __inline 401 int 402 sequential_heuristic(struct uio *uio, struct file *fp) 403 { 404 /* 405 * Sequential heuristic - detect sequential operation 406 */ 407 if ((uio->uio_offset == 0 && fp->f_seqcount > 0) || 408 uio->uio_offset == fp->f_nextoff) { 409 int tmpseq = fp->f_seqcount; 410 /* 411 * XXX we assume that the filesystem block size is 412 * the default. Not true, but still gives us a pretty 413 * good indicator of how sequential the read operations 414 * are. 415 */ 416 tmpseq += (uio->uio_resid + BKVASIZE - 1) / BKVASIZE; 417 if (tmpseq > IO_SEQMAX) 418 tmpseq = IO_SEQMAX; 419 fp->f_seqcount = tmpseq; 420 return(fp->f_seqcount << IO_SEQSHIFT); 421 } 422 423 /* 424 * Not sequential, quick draw-down of seqcount 425 */ 426 if (fp->f_seqcount > 1) 427 fp->f_seqcount = 1; 428 else 429 fp->f_seqcount = 0; 430 return(0); 431 } 432 433 /* 434 * Package up an I/O request on a vnode into a uio and do it. 435 */ 436 int 437 vn_rdwr(enum uio_rw rw, struct vnode *vp, caddr_t base, int len, 438 off_t offset, enum uio_seg segflg, int ioflg, 439 struct ucred *cred, int *aresid) 440 { 441 struct uio auio; 442 struct iovec aiov; 443 struct ccms_lock ccms_lock; 444 int error; 445 446 if ((ioflg & IO_NODELOCKED) == 0) 447 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 448 auio.uio_iov = &aiov; 449 auio.uio_iovcnt = 1; 450 aiov.iov_base = base; 451 aiov.iov_len = len; 452 auio.uio_resid = len; 453 auio.uio_offset = offset; 454 auio.uio_segflg = segflg; 455 auio.uio_rw = rw; 456 auio.uio_td = curthread; 457 ccms_lock_get_uio(&vp->v_ccms, &ccms_lock, &auio); 458 if (rw == UIO_READ) { 459 error = VOP_READ(vp, &auio, ioflg, cred); 460 } else { 461 error = VOP_WRITE(vp, &auio, ioflg, cred); 462 } 463 ccms_lock_put(&vp->v_ccms, &ccms_lock); 464 if (aresid) 465 *aresid = auio.uio_resid; 466 else 467 if (auio.uio_resid && error == 0) 468 error = EIO; 469 if ((ioflg & IO_NODELOCKED) == 0) 470 vn_unlock(vp); 471 return (error); 472 } 473 474 /* 475 * Package up an I/O request on a vnode into a uio and do it. The I/O 476 * request is split up into smaller chunks and we try to avoid saturating 477 * the buffer cache while potentially holding a vnode locked, so we 478 * check bwillwrite() before calling vn_rdwr(). We also call uio_yield() 479 * to give other processes a chance to lock the vnode (either other processes 480 * core'ing the same binary, or unrelated processes scanning the directory). 481 */ 482 int 483 vn_rdwr_inchunks(enum uio_rw rw, struct vnode *vp, caddr_t base, int len, 484 off_t offset, enum uio_seg segflg, int ioflg, 485 struct ucred *cred, int *aresid) 486 { 487 int error = 0; 488 489 do { 490 int chunk; 491 492 /* 493 * Force `offset' to a multiple of MAXBSIZE except possibly 494 * for the first chunk, so that filesystems only need to 495 * write full blocks except possibly for the first and last 496 * chunks. 497 */ 498 chunk = MAXBSIZE - (uoff_t)offset % MAXBSIZE; 499 500 if (chunk > len) 501 chunk = len; 502 if (rw != UIO_READ && vp->v_type == VREG) 503 bwillwrite(); 504 error = vn_rdwr(rw, vp, base, chunk, offset, segflg, 505 ioflg, cred, aresid); 506 len -= chunk; /* aresid calc already includes length */ 507 if (error) 508 break; 509 offset += chunk; 510 base += chunk; 511 uio_yield(); 512 } while (len); 513 if (aresid) 514 *aresid += len; 515 return (error); 516 } 517 518 /* 519 * MPALMOSTSAFE - acquires mplock 520 */ 521 static int 522 vn_read(struct file *fp, struct uio *uio, struct ucred *cred, int flags) 523 { 524 struct ccms_lock ccms_lock; 525 struct vnode *vp; 526 int error, ioflag; 527 528 get_mplock(); 529 KASSERT(uio->uio_td == curthread, 530 ("uio_td %p is not td %p", uio->uio_td, curthread)); 531 vp = (struct vnode *)fp->f_data; 532 533 ioflag = 0; 534 if (flags & O_FBLOCKING) { 535 /* ioflag &= ~IO_NDELAY; */ 536 } else if (flags & O_FNONBLOCKING) { 537 ioflag |= IO_NDELAY; 538 } else if (fp->f_flag & FNONBLOCK) { 539 ioflag |= IO_NDELAY; 540 } 541 if (flags & O_FBUFFERED) { 542 /* ioflag &= ~IO_DIRECT; */ 543 } else if (flags & O_FUNBUFFERED) { 544 ioflag |= IO_DIRECT; 545 } else if (fp->f_flag & O_DIRECT) { 546 ioflag |= IO_DIRECT; 547 } 548 vn_lock(vp, LK_SHARED | LK_RETRY); 549 if ((flags & O_FOFFSET) == 0) 550 uio->uio_offset = fp->f_offset; 551 ioflag |= sequential_heuristic(uio, fp); 552 553 ccms_lock_get_uio(&vp->v_ccms, &ccms_lock, uio); 554 error = VOP_READ(vp, uio, ioflag, cred); 555 ccms_lock_put(&vp->v_ccms, &ccms_lock); 556 if ((flags & O_FOFFSET) == 0) 557 fp->f_offset = uio->uio_offset; 558 fp->f_nextoff = uio->uio_offset; 559 vn_unlock(vp); 560 rel_mplock(); 561 return (error); 562 } 563 564 /* 565 * Device-optimized file table vnode read routine. 566 * 567 * This bypasses the VOP table and talks directly to the device. Most 568 * filesystems just route to specfs and can make this optimization. 569 * 570 * MPALMOSTSAFE - acquires mplock 571 */ 572 static int 573 svn_read(struct file *fp, struct uio *uio, struct ucred *cred, int flags) 574 { 575 struct vnode *vp; 576 int ioflag; 577 int error; 578 cdev_t dev; 579 580 get_mplock(); 581 KASSERT(uio->uio_td == curthread, 582 ("uio_td %p is not td %p", uio->uio_td, curthread)); 583 584 vp = (struct vnode *)fp->f_data; 585 if (vp == NULL || vp->v_type == VBAD) { 586 error = EBADF; 587 goto done; 588 } 589 590 if ((dev = vp->v_rdev) == NULL) { 591 error = EBADF; 592 goto done; 593 } 594 reference_dev(dev); 595 596 if (uio->uio_resid == 0) { 597 error = 0; 598 goto done; 599 } 600 if ((flags & O_FOFFSET) == 0) 601 uio->uio_offset = fp->f_offset; 602 603 ioflag = 0; 604 if (flags & O_FBLOCKING) { 605 /* ioflag &= ~IO_NDELAY; */ 606 } else if (flags & O_FNONBLOCKING) { 607 ioflag |= IO_NDELAY; 608 } else if (fp->f_flag & FNONBLOCK) { 609 ioflag |= IO_NDELAY; 610 } 611 if (flags & O_FBUFFERED) { 612 /* ioflag &= ~IO_DIRECT; */ 613 } else if (flags & O_FUNBUFFERED) { 614 ioflag |= IO_DIRECT; 615 } else if (fp->f_flag & O_DIRECT) { 616 ioflag |= IO_DIRECT; 617 } 618 ioflag |= sequential_heuristic(uio, fp); 619 620 error = dev_dread(dev, uio, ioflag); 621 622 release_dev(dev); 623 if ((flags & O_FOFFSET) == 0) 624 fp->f_offset = uio->uio_offset; 625 fp->f_nextoff = uio->uio_offset; 626 done: 627 rel_mplock(); 628 return (error); 629 } 630 631 /* 632 * MPALMOSTSAFE - acquires mplock 633 */ 634 static int 635 vn_write(struct file *fp, struct uio *uio, struct ucred *cred, int flags) 636 { 637 struct ccms_lock ccms_lock; 638 struct vnode *vp; 639 int error, ioflag; 640 641 get_mplock(); 642 KASSERT(uio->uio_td == curthread, 643 ("uio_procp %p is not p %p", uio->uio_td, curthread)); 644 vp = (struct vnode *)fp->f_data; 645 if (vp->v_type == VREG) 646 bwillwrite(); 647 vp = (struct vnode *)fp->f_data; /* XXX needed? */ 648 649 ioflag = IO_UNIT; 650 if (vp->v_type == VREG && 651 ((fp->f_flag & O_APPEND) || (flags & O_FAPPEND))) { 652 ioflag |= IO_APPEND; 653 } 654 655 if (flags & O_FBLOCKING) { 656 /* ioflag &= ~IO_NDELAY; */ 657 } else if (flags & O_FNONBLOCKING) { 658 ioflag |= IO_NDELAY; 659 } else if (fp->f_flag & FNONBLOCK) { 660 ioflag |= IO_NDELAY; 661 } 662 if (flags & O_FBUFFERED) { 663 /* ioflag &= ~IO_DIRECT; */ 664 } else if (flags & O_FUNBUFFERED) { 665 ioflag |= IO_DIRECT; 666 } else if (fp->f_flag & O_DIRECT) { 667 ioflag |= IO_DIRECT; 668 } 669 if (flags & O_FASYNCWRITE) { 670 /* ioflag &= ~IO_SYNC; */ 671 } else if (flags & O_FSYNCWRITE) { 672 ioflag |= IO_SYNC; 673 } else if (fp->f_flag & O_FSYNC) { 674 ioflag |= IO_SYNC; 675 } 676 677 if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)) 678 ioflag |= IO_SYNC; 679 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY); 680 if ((flags & O_FOFFSET) == 0) 681 uio->uio_offset = fp->f_offset; 682 ioflag |= sequential_heuristic(uio, fp); 683 ccms_lock_get_uio(&vp->v_ccms, &ccms_lock, uio); 684 error = VOP_WRITE(vp, uio, ioflag, cred); 685 ccms_lock_put(&vp->v_ccms, &ccms_lock); 686 if ((flags & O_FOFFSET) == 0) 687 fp->f_offset = uio->uio_offset; 688 fp->f_nextoff = uio->uio_offset; 689 vn_unlock(vp); 690 rel_mplock(); 691 return (error); 692 } 693 694 /* 695 * Device-optimized file table vnode write routine. 696 * 697 * This bypasses the VOP table and talks directly to the device. Most 698 * filesystems just route to specfs and can make this optimization. 699 * 700 * MPALMOSTSAFE - acquires mplock 701 */ 702 static int 703 svn_write(struct file *fp, struct uio *uio, struct ucred *cred, int flags) 704 { 705 struct vnode *vp; 706 int ioflag; 707 int error; 708 cdev_t dev; 709 710 get_mplock(); 711 KASSERT(uio->uio_td == curthread, 712 ("uio_procp %p is not p %p", uio->uio_td, curthread)); 713 714 vp = (struct vnode *)fp->f_data; 715 if (vp == NULL || vp->v_type == VBAD) { 716 error = EBADF; 717 goto done; 718 } 719 if (vp->v_type == VREG) 720 bwillwrite(); 721 vp = (struct vnode *)fp->f_data; /* XXX needed? */ 722 723 if ((dev = vp->v_rdev) == NULL) { 724 error = EBADF; 725 goto done; 726 } 727 reference_dev(dev); 728 729 if ((flags & O_FOFFSET) == 0) 730 uio->uio_offset = fp->f_offset; 731 732 ioflag = IO_UNIT; 733 if (vp->v_type == VREG && 734 ((fp->f_flag & O_APPEND) || (flags & O_FAPPEND))) { 735 ioflag |= IO_APPEND; 736 } 737 738 if (flags & O_FBLOCKING) { 739 /* ioflag &= ~IO_NDELAY; */ 740 } else if (flags & O_FNONBLOCKING) { 741 ioflag |= IO_NDELAY; 742 } else if (fp->f_flag & FNONBLOCK) { 743 ioflag |= IO_NDELAY; 744 } 745 if (flags & O_FBUFFERED) { 746 /* ioflag &= ~IO_DIRECT; */ 747 } else if (flags & O_FUNBUFFERED) { 748 ioflag |= IO_DIRECT; 749 } else if (fp->f_flag & O_DIRECT) { 750 ioflag |= IO_DIRECT; 751 } 752 if (flags & O_FASYNCWRITE) { 753 /* ioflag &= ~IO_SYNC; */ 754 } else if (flags & O_FSYNCWRITE) { 755 ioflag |= IO_SYNC; 756 } else if (fp->f_flag & O_FSYNC) { 757 ioflag |= IO_SYNC; 758 } 759 760 if (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)) 761 ioflag |= IO_SYNC; 762 ioflag |= sequential_heuristic(uio, fp); 763 764 error = dev_dwrite(dev, uio, ioflag); 765 766 release_dev(dev); 767 if ((flags & O_FOFFSET) == 0) 768 fp->f_offset = uio->uio_offset; 769 fp->f_nextoff = uio->uio_offset; 770 done: 771 rel_mplock(); 772 return (error); 773 } 774 775 /* 776 * MPALMOSTSAFE - acquires mplock 777 */ 778 static int 779 vn_statfile(struct file *fp, struct stat *sb, struct ucred *cred) 780 { 781 struct vnode *vp; 782 int error; 783 784 get_mplock(); 785 vp = (struct vnode *)fp->f_data; 786 error = vn_stat(vp, sb, cred); 787 rel_mplock(); 788 return (error); 789 } 790 791 int 792 vn_stat(struct vnode *vp, struct stat *sb, struct ucred *cred) 793 { 794 struct vattr vattr; 795 struct vattr *vap; 796 int error; 797 u_short mode; 798 cdev_t dev; 799 800 vap = &vattr; 801 error = VOP_GETATTR(vp, vap); 802 if (error) 803 return (error); 804 805 /* 806 * Zero the spare stat fields 807 */ 808 sb->st_lspare = 0; 809 sb->st_qspare = 0; 810 811 /* 812 * Copy from vattr table 813 */ 814 if (vap->va_fsid != VNOVAL) 815 sb->st_dev = vap->va_fsid; 816 else 817 sb->st_dev = vp->v_mount->mnt_stat.f_fsid.val[0]; 818 sb->st_ino = vap->va_fileid; 819 mode = vap->va_mode; 820 switch (vap->va_type) { 821 case VREG: 822 mode |= S_IFREG; 823 break; 824 case VDIR: 825 mode |= S_IFDIR; 826 break; 827 case VBLK: 828 mode |= S_IFBLK; 829 break; 830 case VCHR: 831 mode |= S_IFCHR; 832 break; 833 case VLNK: 834 mode |= S_IFLNK; 835 /* This is a cosmetic change, symlinks do not have a mode. */ 836 if (vp->v_mount->mnt_flag & MNT_NOSYMFOLLOW) 837 sb->st_mode &= ~ACCESSPERMS; /* 0000 */ 838 else 839 sb->st_mode |= ACCESSPERMS; /* 0777 */ 840 break; 841 case VSOCK: 842 mode |= S_IFSOCK; 843 break; 844 case VFIFO: 845 mode |= S_IFIFO; 846 break; 847 default: 848 return (EBADF); 849 }; 850 sb->st_mode = mode; 851 sb->st_nlink = vap->va_nlink; 852 sb->st_uid = vap->va_uid; 853 sb->st_gid = vap->va_gid; 854 sb->st_rdev = vap->va_rdev; 855 sb->st_size = vap->va_size; 856 sb->st_atimespec = vap->va_atime; 857 sb->st_mtimespec = vap->va_mtime; 858 sb->st_ctimespec = vap->va_ctime; 859 860 /* 861 * A VCHR and VBLK device may track the last access and last modified 862 * time independantly of the filesystem. This is particularly true 863 * because device read and write calls may bypass the filesystem. 864 */ 865 if (vp->v_type == VCHR || vp->v_type == VBLK) { 866 if ((dev = vp->v_rdev) != NULL) { 867 if (dev->si_lastread) { 868 sb->st_atimespec.tv_sec = dev->si_lastread; 869 sb->st_atimespec.tv_nsec = 0; 870 } 871 if (dev->si_lastwrite) { 872 sb->st_atimespec.tv_sec = dev->si_lastwrite; 873 sb->st_atimespec.tv_nsec = 0; 874 } 875 } 876 } 877 878 /* 879 * According to www.opengroup.org, the meaning of st_blksize is 880 * "a filesystem-specific preferred I/O block size for this 881 * object. In some filesystem types, this may vary from file 882 * to file" 883 * Default to PAGE_SIZE after much discussion. 884 */ 885 886 if (vap->va_type == VREG) { 887 sb->st_blksize = vap->va_blocksize; 888 } else if (vn_isdisk(vp, NULL)) { 889 /* 890 * XXX this is broken. If the device is not yet open (aka 891 * stat() call, aka v_rdev == NULL), how are we supposed 892 * to get a valid block size out of it? 893 */ 894 cdev_t dev; 895 896 if ((dev = vp->v_rdev) == NULL) 897 dev = udev2dev(vp->v_udev, vp->v_type == VBLK); 898 sb->st_blksize = dev->si_bsize_best; 899 if (sb->st_blksize < dev->si_bsize_phys) 900 sb->st_blksize = dev->si_bsize_phys; 901 if (sb->st_blksize < BLKDEV_IOSIZE) 902 sb->st_blksize = BLKDEV_IOSIZE; 903 } else { 904 sb->st_blksize = PAGE_SIZE; 905 } 906 907 sb->st_flags = vap->va_flags; 908 if (suser_cred(cred, 0)) 909 sb->st_gen = 0; 910 else 911 sb->st_gen = vap->va_gen; 912 913 #if (S_BLKSIZE == 512) 914 /* Optimize this case */ 915 sb->st_blocks = vap->va_bytes >> 9; 916 #else 917 sb->st_blocks = vap->va_bytes / S_BLKSIZE; 918 #endif 919 sb->st_fsmid = vap->va_fsmid; 920 return (0); 921 } 922 923 /* 924 * MPALMOSTSAFE - acquires mplock 925 */ 926 static int 927 vn_ioctl(struct file *fp, u_long com, caddr_t data, struct ucred *ucred) 928 { 929 struct vnode *vp = ((struct vnode *)fp->f_data); 930 struct vnode *ovp; 931 struct vattr vattr; 932 int error; 933 934 get_mplock(); 935 936 switch (vp->v_type) { 937 case VREG: 938 case VDIR: 939 if (com == FIONREAD) { 940 if ((error = VOP_GETATTR(vp, &vattr)) != 0) 941 break; 942 *(int *)data = vattr.va_size - fp->f_offset; 943 error = 0; 944 break; 945 } 946 if (com == FIOASYNC) { /* XXX */ 947 error = 0; /* XXX */ 948 break; 949 } 950 /* fall into ... */ 951 default: 952 #if 0 953 return (ENOTTY); 954 #endif 955 case VFIFO: 956 case VCHR: 957 case VBLK: 958 if (com == FIODTYPE) { 959 if (vp->v_type != VCHR && vp->v_type != VBLK) { 960 error = ENOTTY; 961 break; 962 } 963 *(int *)data = dev_dflags(vp->v_rdev) & D_TYPEMASK; 964 error = 0; 965 break; 966 } 967 error = VOP_IOCTL(vp, com, data, fp->f_flag, ucred); 968 if (error == 0 && com == TIOCSCTTY) { 969 struct proc *p = curthread->td_proc; 970 struct session *sess; 971 972 if (p == NULL) { 973 error = ENOTTY; 974 break; 975 } 976 977 sess = p->p_session; 978 /* Do nothing if reassigning same control tty */ 979 if (sess->s_ttyvp == vp) { 980 error = 0; 981 break; 982 } 983 984 /* Get rid of reference to old control tty */ 985 ovp = sess->s_ttyvp; 986 vref(vp); 987 sess->s_ttyvp = vp; 988 if (ovp) 989 vrele(ovp); 990 } 991 break; 992 } 993 rel_mplock(); 994 return (error); 995 } 996 997 /* 998 * MPALMOSTSAFE - acquires mplock 999 */ 1000 static int 1001 vn_poll(struct file *fp, int events, struct ucred *cred) 1002 { 1003 int error; 1004 1005 get_mplock(); 1006 error = VOP_POLL(((struct vnode *)fp->f_data), events, cred); 1007 rel_mplock(); 1008 return (error); 1009 } 1010 1011 /* 1012 * Check that the vnode is still valid, and if so 1013 * acquire requested lock. 1014 */ 1015 int 1016 #ifndef DEBUG_LOCKS 1017 vn_lock(struct vnode *vp, int flags) 1018 #else 1019 debug_vn_lock(struct vnode *vp, int flags, const char *filename, int line) 1020 #endif 1021 { 1022 int error; 1023 1024 do { 1025 #ifdef DEBUG_LOCKS 1026 vp->filename = filename; 1027 vp->line = line; 1028 error = debuglockmgr(&vp->v_lock, flags, 1029 "vn_lock", filename, line); 1030 #else 1031 error = lockmgr(&vp->v_lock, flags); 1032 #endif 1033 if (error == 0) 1034 break; 1035 } while (flags & LK_RETRY); 1036 1037 /* 1038 * Because we (had better!) have a ref on the vnode, once it 1039 * goes to VRECLAIMED state it will not be recycled until all 1040 * refs go away. So we can just check the flag. 1041 */ 1042 if (error == 0 && (vp->v_flag & VRECLAIMED)) { 1043 lockmgr(&vp->v_lock, LK_RELEASE); 1044 error = ENOENT; 1045 } 1046 return (error); 1047 } 1048 1049 void 1050 vn_unlock(struct vnode *vp) 1051 { 1052 lockmgr(&vp->v_lock, LK_RELEASE); 1053 } 1054 1055 int 1056 vn_islocked(struct vnode *vp) 1057 { 1058 return (lockstatus(&vp->v_lock, curthread)); 1059 } 1060 1061 /* 1062 * MPALMOSTSAFE - acquires mplock 1063 */ 1064 static int 1065 vn_closefile(struct file *fp) 1066 { 1067 int error; 1068 1069 get_mplock(); 1070 fp->f_ops = &badfileops; 1071 error = vn_close(((struct vnode *)fp->f_data), fp->f_flag); 1072 rel_mplock(); 1073 return(error); 1074 } 1075 1076 /* 1077 * MPALMOSTSAFE - acquires mplock 1078 */ 1079 static int 1080 vn_kqfilter(struct file *fp, struct knote *kn) 1081 { 1082 int error; 1083 1084 get_mplock(); 1085 error = VOP_KQFILTER(((struct vnode *)fp->f_data), kn); 1086 rel_mplock(); 1087 return (error); 1088 } 1089