FreeBSD kernel kern code
vfs_vnops.c
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1/*-
2 * SPDX-License-Identifier: BSD-3-Clause
3 *
4 * Copyright (c) 1982, 1986, 1989, 1993
5 * The Regents of the University of California. All rights reserved.
6 * (c) UNIX System Laboratories, Inc.
7 * All or some portions of this file are derived from material licensed
8 * to the University of California by American Telephone and Telegraph
9 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
10 * the permission of UNIX System Laboratories, Inc.
11 *
12 * Copyright (c) 2012 Konstantin Belousov <kib@FreeBSD.org>
13 * Copyright (c) 2013, 2014 The FreeBSD Foundation
14 *
15 * Portions of this software were developed by Konstantin Belousov
16 * under sponsorship from the FreeBSD Foundation.
17 *
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted provided that the following conditions
20 * are met:
21 * 1. Redistributions of source code must retain the above copyright
22 * notice, this list of conditions and the following disclaimer.
23 * 2. Redistributions in binary form must reproduce the above copyright
24 * notice, this list of conditions and the following disclaimer in the
25 * documentation and/or other materials provided with the distribution.
26 * 3. Neither the name of the University nor the names of its contributors
27 * may be used to endorse or promote products derived from this software
28 * without specific prior written permission.
29 *
30 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
31 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
32 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
33 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
34 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
35 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
36 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
37 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
38 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
39 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40 * SUCH DAMAGE.
41 *
42 * @(#)vfs_vnops.c 8.2 (Berkeley) 1/21/94
43 */
44
45#include <sys/cdefs.h>
46__FBSDID("$FreeBSD$");
47
48#include "opt_hwpmc_hooks.h"
49
50#include <sys/param.h>
51#include <sys/systm.h>
52#include <sys/disk.h>
53#include <sys/fail.h>
54#include <sys/fcntl.h>
55#include <sys/file.h>
56#include <sys/kdb.h>
57#include <sys/ktr.h>
58#include <sys/stat.h>
59#include <sys/priv.h>
60#include <sys/proc.h>
61#include <sys/limits.h>
62#include <sys/lock.h>
63#include <sys/mman.h>
64#include <sys/mount.h>
65#include <sys/mutex.h>
66#include <sys/namei.h>
67#include <sys/vnode.h>
68#include <sys/bio.h>
69#include <sys/buf.h>
70#include <sys/filio.h>
71#include <sys/resourcevar.h>
72#include <sys/rwlock.h>
73#include <sys/prng.h>
74#include <sys/sx.h>
75#include <sys/sleepqueue.h>
76#include <sys/sysctl.h>
77#include <sys/ttycom.h>
78#include <sys/conf.h>
79#include <sys/syslog.h>
80#include <sys/unistd.h>
81#include <sys/user.h>
82#include <sys/ktrace.h>
83
84#include <security/audit/audit.h>
85#include <security/mac/mac_framework.h>
86
87#include <vm/vm.h>
88#include <vm/vm_extern.h>
89#include <vm/pmap.h>
90#include <vm/vm_map.h>
91#include <vm/vm_object.h>
92#include <vm/vm_page.h>
93#include <vm/vm_pager.h>
94
95#ifdef HWPMC_HOOKS
96#include <sys/pmckern.h>
97#endif
98
99static fo_rdwr_t vn_read;
100static fo_rdwr_t vn_write;
101static fo_rdwr_t vn_io_fault;
102static fo_truncate_t vn_truncate;
103static fo_ioctl_t vn_ioctl;
104static fo_poll_t vn_poll;
105static fo_kqfilter_t vn_kqfilter;
106static fo_close_t vn_closefile;
107static fo_mmap_t vn_mmap;
108static fo_fallocate_t vn_fallocate;
109static fo_fspacectl_t vn_fspacectl;
110
111struct fileops vnops = {
112 .fo_read = vn_io_fault,
113 .fo_write = vn_io_fault,
114 .fo_truncate = vn_truncate,
115 .fo_ioctl = vn_ioctl,
116 .fo_poll = vn_poll,
117 .fo_kqfilter = vn_kqfilter,
118 .fo_stat = vn_statfile,
119 .fo_close = vn_closefile,
120 .fo_chmod = vn_chmod,
121 .fo_chown = vn_chown,
122 .fo_sendfile = vn_sendfile,
123 .fo_seek = vn_seek,
124 .fo_fill_kinfo = vn_fill_kinfo,
125 .fo_mmap = vn_mmap,
126 .fo_fallocate = vn_fallocate,
127 .fo_fspacectl = vn_fspacectl,
128 .fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE
129};
130
131const u_int io_hold_cnt = 16;
132static int vn_io_fault_enable = 1;
133SYSCTL_INT(_debug, OID_AUTO, vn_io_fault_enable, CTLFLAG_RWTUN,
134 &vn_io_fault_enable, 0, "Enable vn_io_fault lock avoidance");
135static int vn_io_fault_prefault = 0;
136SYSCTL_INT(_debug, OID_AUTO, vn_io_fault_prefault, CTLFLAG_RWTUN,
137 &vn_io_fault_prefault, 0, "Enable vn_io_fault prefaulting");
138static int vn_io_pgcache_read_enable = 1;
139SYSCTL_INT(_debug, OID_AUTO, vn_io_pgcache_read_enable, CTLFLAG_RWTUN,
140 &vn_io_pgcache_read_enable, 0,
141 "Enable copying from page cache for reads, avoiding fs");
142static u_long vn_io_faults_cnt;
143SYSCTL_ULONG(_debug, OID_AUTO, vn_io_faults, CTLFLAG_RD,
144 &vn_io_faults_cnt, 0, "Count of vn_io_fault lock avoidance triggers");
145
146static int vfs_allow_read_dir = 0;
147SYSCTL_INT(_security_bsd, OID_AUTO, allow_read_dir, CTLFLAG_RW,
148 &vfs_allow_read_dir, 0,
149 "Enable read(2) of directory by root for filesystems that support it");
150
151/*
152 * Returns true if vn_io_fault mode of handling the i/o request should
153 * be used.
154 */
155static bool
156do_vn_io_fault(struct vnode *vp, struct uio *uio)
157{
158 struct mount *mp;
159
160 return (uio->uio_segflg == UIO_USERSPACE && vp->v_type == VREG &&
161 (mp = vp->v_mount) != NULL &&
162 (mp->mnt_kern_flag & MNTK_NO_IOPF) != 0 && vn_io_fault_enable);
163}
164
165/*
166 * Structure used to pass arguments to vn_io_fault1(), to do either
167 * file- or vnode-based I/O calls.
168 */
169struct vn_io_fault_args {
170 enum {
171 VN_IO_FAULT_FOP,
172 VN_IO_FAULT_VOP
173 } kind;
174 struct ucred *cred;
175 int flags;
176 union {
177 struct fop_args_tag {
178 struct file *fp;
179 fo_rdwr_t *doio;
180 } fop_args;
181 struct vop_args_tag {
182 struct vnode *vp;
183 } vop_args;
184 } args;
185};
186
187static int vn_io_fault1(struct vnode *vp, struct uio *uio,
188 struct vn_io_fault_args *args, struct thread *td);
189
190int
191vn_open(struct nameidata *ndp, int *flagp, int cmode, struct file *fp)
192{
193 struct thread *td = curthread;
194
195 return (vn_open_cred(ndp, flagp, cmode, 0, td->td_ucred, fp));
196}
197
198static uint64_t
199open2nameif(int fmode, u_int vn_open_flags)
200{
201 uint64_t res;
202
203 res = ISOPEN | LOCKLEAF;
204 if ((fmode & O_RESOLVE_BENEATH) != 0)
205 res |= RBENEATH;
206 if ((fmode & O_EMPTY_PATH) != 0)
207 res |= EMPTYPATH;
208 if ((fmode & FREAD) != 0)
209 res |= OPENREAD;
210 if ((fmode & FWRITE) != 0)
211 res |= OPENWRITE;
212 if ((vn_open_flags & VN_OPEN_NOAUDIT) == 0)
213 res |= AUDITVNODE1;
214 if ((vn_open_flags & VN_OPEN_NOCAPCHECK) != 0)
215 res |= NOCAPCHECK;
216 return (res);
217}
218
219/*
220 * Common code for vnode open operations via a name lookup.
221 * Lookup the vnode and invoke VOP_CREATE if needed.
222 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine.
223 *
224 * Note that this does NOT free nameidata for the successful case,
225 * due to the NDINIT being done elsewhere.
226 */
227int
228vn_open_cred(struct nameidata *ndp, int *flagp, int cmode, u_int vn_open_flags,
229 struct ucred *cred, struct file *fp)
230{
231 struct vnode *vp;
232 struct mount *mp;
233 struct vattr vat;
234 struct vattr *vap = &vat;
235 int fmode, error;
236 bool first_open;
237
238restart:
239 first_open = false;
240 fmode = *flagp;
241 if ((fmode & (O_CREAT | O_EXCL | O_DIRECTORY)) == (O_CREAT |
242 O_EXCL | O_DIRECTORY) ||
243 (fmode & (O_CREAT | O_EMPTY_PATH)) == (O_CREAT | O_EMPTY_PATH))
244 return (EINVAL);
245 else if ((fmode & (O_CREAT | O_DIRECTORY)) == O_CREAT) {
246 ndp->ni_cnd.cn_nameiop = CREATE;
247 ndp->ni_cnd.cn_flags = open2nameif(fmode, vn_open_flags);
248 /*
249 * Set NOCACHE to avoid flushing the cache when
250 * rolling in many files at once.
251 *
252 * Set NC_KEEPPOSENTRY to keep positive entries if they already
253 * exist despite NOCACHE.
254 */
255 ndp->ni_cnd.cn_flags |= LOCKPARENT | NOCACHE | NC_KEEPPOSENTRY;
256 if ((fmode & O_EXCL) == 0 && (fmode & O_NOFOLLOW) == 0)
257 ndp->ni_cnd.cn_flags |= FOLLOW;
258 if ((vn_open_flags & VN_OPEN_INVFS) == 0)
259 bwillwrite();
260 if ((error = namei(ndp)) != 0)
261 return (error);
262 if (ndp->ni_vp == NULL) {
263 VATTR_NULL(vap);
264 vap->va_type = VREG;
265 vap->va_mode = cmode;
266 if (fmode & O_EXCL)
267 vap->va_vaflags |= VA_EXCLUSIVE;
268 if (vn_start_write(ndp->ni_dvp, &mp, V_NOWAIT) != 0) {
269 NDFREE(ndp, NDF_ONLY_PNBUF);
270 vput(ndp->ni_dvp);
271 if ((error = vn_start_write(NULL, &mp,
272 V_XSLEEP | PCATCH)) != 0)
273 return (error);
274 NDREINIT(ndp);
275 goto restart;
276 }
277 if ((vn_open_flags & VN_OPEN_NAMECACHE) != 0)
278 ndp->ni_cnd.cn_flags |= MAKEENTRY;
279#ifdef MAC
280 error = mac_vnode_check_create(cred, ndp->ni_dvp,
281 &ndp->ni_cnd, vap);
282 if (error == 0)
283#endif
284 error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp,
285 &ndp->ni_cnd, vap);
286 vp = ndp->ni_vp;
287 if (error == 0 && (fmode & O_EXCL) != 0 &&
288 (fmode & (O_EXLOCK | O_SHLOCK)) != 0) {
289 VI_LOCK(vp);
290 vp->v_iflag |= VI_FOPENING;
291 VI_UNLOCK(vp);
292 first_open = true;
293 }
294 VOP_VPUT_PAIR(ndp->ni_dvp, error == 0 ? &vp : NULL,
295 false);
296 vn_finished_write(mp);
297 if (error) {
298 NDFREE(ndp, NDF_ONLY_PNBUF);
299 if (error == ERELOOKUP) {
300 NDREINIT(ndp);
301 goto restart;
302 }
303 return (error);
304 }
305 fmode &= ~O_TRUNC;
306 } else {
307 if (ndp->ni_dvp == ndp->ni_vp)
308 vrele(ndp->ni_dvp);
309 else
310 vput(ndp->ni_dvp);
311 ndp->ni_dvp = NULL;
312 vp = ndp->ni_vp;
313 if (fmode & O_EXCL) {
314 error = EEXIST;
315 goto bad;
316 }
317 if (vp->v_type == VDIR) {
318 error = EISDIR;
319 goto bad;
320 }
321 fmode &= ~O_CREAT;
322 }
323 } else {
324 ndp->ni_cnd.cn_nameiop = LOOKUP;
325 ndp->ni_cnd.cn_flags = open2nameif(fmode, vn_open_flags);
326 ndp->ni_cnd.cn_flags |= (fmode & O_NOFOLLOW) != 0 ? NOFOLLOW :
327 FOLLOW;
328 if ((fmode & FWRITE) == 0)
329 ndp->ni_cnd.cn_flags |= LOCKSHARED;
330 if ((error = namei(ndp)) != 0)
331 return (error);
332 vp = ndp->ni_vp;
333 }
334 error = vn_open_vnode(vp, fmode, cred, curthread, fp);
335 if (first_open) {
336 VI_LOCK(vp);
337 vp->v_iflag &= ~VI_FOPENING;
338 wakeup(vp);
339 VI_UNLOCK(vp);
340 }
341 if (error)
342 goto bad;
343 *flagp = fmode;
344 return (0);
345bad:
346 NDFREE(ndp, NDF_ONLY_PNBUF);
347 vput(vp);
348 *flagp = fmode;
349 ndp->ni_vp = NULL;
350 return (error);
351}
352
353static int
354vn_open_vnode_advlock(struct vnode *vp, int fmode, struct file *fp)
355{
356 struct flock lf;
357 int error, lock_flags, type;
358
359 ASSERT_VOP_LOCKED(vp, "vn_open_vnode_advlock");
360 if ((fmode & (O_EXLOCK | O_SHLOCK)) == 0)
361 return (0);
362 KASSERT(fp != NULL, ("open with flock requires fp"));
363 if (fp->f_type != DTYPE_NONE && fp->f_type != DTYPE_VNODE)
364 return (EOPNOTSUPP);
365
366 lock_flags = VOP_ISLOCKED(vp);
367 VOP_UNLOCK(vp);
368
369 lf.l_whence = SEEK_SET;
370 lf.l_start = 0;
371 lf.l_len = 0;
372 lf.l_type = (fmode & O_EXLOCK) != 0 ? F_WRLCK : F_RDLCK;
373 type = F_FLOCK;
374 if ((fmode & FNONBLOCK) == 0)
375 type |= F_WAIT;
376 if ((fmode & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
377 type |= F_FIRSTOPEN;
378 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, type);
379 if (error == 0)
380 fp->f_flag |= FHASLOCK;
381
382 vn_lock(vp, lock_flags | LK_RETRY);
383 return (error);
384}
385
386/*
387 * Common code for vnode open operations once a vnode is located.
388 * Check permissions, and call the VOP_OPEN routine.
389 */
390int
391vn_open_vnode(struct vnode *vp, int fmode, struct ucred *cred,
392 struct thread *td, struct file *fp)
393{
394 accmode_t accmode;
395 int error;
396
397 if (vp->v_type == VLNK) {
398 if ((fmode & O_PATH) == 0 || (fmode & FEXEC) != 0)
399 return (EMLINK);
400 }
401 if (vp->v_type != VDIR && fmode & O_DIRECTORY)
402 return (ENOTDIR);
403
404 accmode = 0;
405 if ((fmode & O_PATH) == 0) {
406 if (vp->v_type == VSOCK)
407 return (EOPNOTSUPP);
408 if ((fmode & (FWRITE | O_TRUNC)) != 0) {
409 if (vp->v_type == VDIR)
410 return (EISDIR);
411 accmode |= VWRITE;
412 }
413 if ((fmode & FREAD) != 0)
414 accmode |= VREAD;
415 if ((fmode & O_APPEND) && (fmode & FWRITE))
416 accmode |= VAPPEND;
417#ifdef MAC
418 if ((fmode & O_CREAT) != 0)
419 accmode |= VCREAT;
420#endif
421 }
422 if ((fmode & FEXEC) != 0)
423 accmode |= VEXEC;
424#ifdef MAC
425 if ((fmode & O_VERIFY) != 0)
426 accmode |= VVERIFY;
427 error = mac_vnode_check_open(cred, vp, accmode);
428 if (error != 0)
429 return (error);
430
431 accmode &= ~(VCREAT | VVERIFY);
432#endif
433 if ((fmode & O_CREAT) == 0 && accmode != 0) {
434 error = VOP_ACCESS(vp, accmode, cred, td);
435 if (error != 0)
436 return (error);
437 }
438 if ((fmode & O_PATH) != 0) {
439 if (vp->v_type != VFIFO && vp->v_type != VSOCK &&
440 VOP_ACCESS(vp, VREAD, cred, td) == 0)
441 fp->f_flag |= FKQALLOWED;
442 return (0);
443 }
444
445 if (vp->v_type == VFIFO && VOP_ISLOCKED(vp) != LK_EXCLUSIVE)
446 vn_lock(vp, LK_UPGRADE | LK_RETRY);
447 error = VOP_OPEN(vp, fmode, cred, td, fp);
448 if (error != 0)
449 return (error);
450
451 error = vn_open_vnode_advlock(vp, fmode, fp);
452 if (error == 0 && (fmode & FWRITE) != 0) {
453 error = VOP_ADD_WRITECOUNT(vp, 1);
454 if (error == 0) {
455 CTR3(KTR_VFS, "%s: vp %p v_writecount increased to %d",
456 __func__, vp, vp->v_writecount);
457 }
458 }
459
460 /*
461 * Error from advlock or VOP_ADD_WRITECOUNT() still requires
462 * calling VOP_CLOSE() to pair with earlier VOP_OPEN().
463 */
464 if (error != 0) {
465 if (fp != NULL) {
466 /*
467 * Arrange the call by having fdrop() to use
468 * vn_closefile(). This is to satisfy
469 * filesystems like devfs or tmpfs, which
470 * override fo_close().
471 */
472 fp->f_flag |= FOPENFAILED;
473 fp->f_vnode = vp;
474 if (fp->f_ops == &badfileops) {
475 fp->f_type = DTYPE_VNODE;
476 fp->f_ops = &vnops;
477 }
478 vref(vp);
479 } else {
480 /*
481 * If there is no fp, due to kernel-mode open,
482 * we can call VOP_CLOSE() now.
483 */
484 if (vp->v_type != VFIFO && (fmode & FWRITE) != 0 &&
485 !MNT_EXTENDED_SHARED(vp->v_mount) &&
486 VOP_ISLOCKED(vp) != LK_EXCLUSIVE)
487 vn_lock(vp, LK_UPGRADE | LK_RETRY);
488 (void)VOP_CLOSE(vp, fmode & (FREAD | FWRITE | FEXEC),
489 cred, td);
490 }
491 }
492
493 ASSERT_VOP_LOCKED(vp, "vn_open_vnode");
494 return (error);
495
496}
497
498/*
499 * Check for write permissions on the specified vnode.
500 * Prototype text segments cannot be written.
501 * It is racy.
502 */
503int
504vn_writechk(struct vnode *vp)
505{
506
507 ASSERT_VOP_LOCKED(vp, "vn_writechk");
508 /*
509 * If there's shared text associated with
510 * the vnode, try to free it up once. If
511 * we fail, we can't allow writing.
512 */
513 if (VOP_IS_TEXT(vp))
514 return (ETXTBSY);
515
516 return (0);
517}
518
519/*
520 * Vnode close call
521 */
522static int
523vn_close1(struct vnode *vp, int flags, struct ucred *file_cred,
524 struct thread *td, bool keep_ref)
525{
526 struct mount *mp;
527 int error, lock_flags;
528
529 if (vp->v_type != VFIFO && (flags & FWRITE) == 0 &&
530 MNT_EXTENDED_SHARED(vp->v_mount))
531 lock_flags = LK_SHARED;
532 else
533 lock_flags = LK_EXCLUSIVE;
534
535 vn_start_write(vp, &mp, V_WAIT);
536 vn_lock(vp, lock_flags | LK_RETRY);
537 AUDIT_ARG_VNODE1(vp);
538 if ((flags & (FWRITE | FOPENFAILED)) == FWRITE) {
539 VOP_ADD_WRITECOUNT_CHECKED(vp, -1);
540 CTR3(KTR_VFS, "%s: vp %p v_writecount decreased to %d",
541 __func__, vp, vp->v_writecount);
542 }
543 error = VOP_CLOSE(vp, flags, file_cred, td);
544 if (keep_ref)
545 VOP_UNLOCK(vp);
546 else
547 vput(vp);
548 vn_finished_write(mp);
549 return (error);
550}
551
552int
553vn_close(struct vnode *vp, int flags, struct ucred *file_cred,
554 struct thread *td)
555{
556
557 return (vn_close1(vp, flags, file_cred, td, false));
558}
559
560/*
561 * Heuristic to detect sequential operation.
562 */
563static int
564sequential_heuristic(struct uio *uio, struct file *fp)
565{
566 enum uio_rw rw;
567
568 ASSERT_VOP_LOCKED(fp->f_vnode, __func__);
569
570 rw = uio->uio_rw;
571 if (fp->f_flag & FRDAHEAD)
572 return (fp->f_seqcount[rw] << IO_SEQSHIFT);
573
574 /*
575 * Offset 0 is handled specially. open() sets f_seqcount to 1 so
576 * that the first I/O is normally considered to be slightly
577 * sequential. Seeking to offset 0 doesn't change sequentiality
578 * unless previous seeks have reduced f_seqcount to 0, in which
579 * case offset 0 is not special.
580 */
581 if ((uio->uio_offset == 0 && fp->f_seqcount[rw] > 0) ||
582 uio->uio_offset == fp->f_nextoff[rw]) {
583 /*
584 * f_seqcount is in units of fixed-size blocks so that it
585 * depends mainly on the amount of sequential I/O and not
586 * much on the number of sequential I/O's. The fixed size
587 * of 16384 is hard-coded here since it is (not quite) just
588 * a magic size that works well here. This size is more
589 * closely related to the best I/O size for real disks than
590 * to any block size used by software.
591 */
592 if (uio->uio_resid >= IO_SEQMAX * 16384)
593 fp->f_seqcount[rw] = IO_SEQMAX;
594 else {
595 fp->f_seqcount[rw] += howmany(uio->uio_resid, 16384);
596 if (fp->f_seqcount[rw] > IO_SEQMAX)
597 fp->f_seqcount[rw] = IO_SEQMAX;
598 }
599 return (fp->f_seqcount[rw] << IO_SEQSHIFT);
600 }
601
602 /* Not sequential. Quickly draw-down sequentiality. */
603 if (fp->f_seqcount[rw] > 1)
604 fp->f_seqcount[rw] = 1;
605 else
606 fp->f_seqcount[rw] = 0;
607 return (0);
608}
609
610/*
611 * Package up an I/O request on a vnode into a uio and do it.
612 */
613int
614vn_rdwr(enum uio_rw rw, struct vnode *vp, void *base, int len, off_t offset,
615 enum uio_seg segflg, int ioflg, struct ucred *active_cred,
616 struct ucred *file_cred, ssize_t *aresid, struct thread *td)
617{
618 struct uio auio;
619 struct iovec aiov;
620 struct mount *mp;
621 struct ucred *cred;
622 void *rl_cookie;
623 struct vn_io_fault_args args;
624 int error, lock_flags;
625
626 if (offset < 0 && vp->v_type != VCHR)
627 return (EINVAL);
628 auio.uio_iov = &aiov;
629 auio.uio_iovcnt = 1;
630 aiov.iov_base = base;
631 aiov.iov_len = len;
632 auio.uio_resid = len;
633 auio.uio_offset = offset;
634 auio.uio_segflg = segflg;
635 auio.uio_rw = rw;
636 auio.uio_td = td;
637 error = 0;
638
639 if ((ioflg & IO_NODELOCKED) == 0) {
640 if ((ioflg & IO_RANGELOCKED) == 0) {
641 if (rw == UIO_READ) {
642 rl_cookie = vn_rangelock_rlock(vp, offset,
643 offset + len);
644 } else if ((ioflg & IO_APPEND) != 0) {
645 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
646 } else {
647 rl_cookie = vn_rangelock_wlock(vp, offset,
648 offset + len);
649 }
650 } else
651 rl_cookie = NULL;
652 mp = NULL;
653 if (rw == UIO_WRITE) {
654 if (vp->v_type != VCHR &&
655 (error = vn_start_write(vp, &mp, V_WAIT | PCATCH))
656 != 0)
657 goto out;
658 lock_flags = vn_lktype_write(mp, vp);
659 } else
660 lock_flags = LK_SHARED;
661 vn_lock(vp, lock_flags | LK_RETRY);
662 } else
663 rl_cookie = NULL;
664
665 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
666#ifdef MAC
667 if ((ioflg & IO_NOMACCHECK) == 0) {
668 if (rw == UIO_READ)
669 error = mac_vnode_check_read(active_cred, file_cred,
670 vp);
671 else
672 error = mac_vnode_check_write(active_cred, file_cred,
673 vp);
674 }
675#endif
676 if (error == 0) {
677 if (file_cred != NULL)
678 cred = file_cred;
679 else
680 cred = active_cred;
681 if (do_vn_io_fault(vp, &auio)) {
682 args.kind = VN_IO_FAULT_VOP;
683 args.cred = cred;
684 args.flags = ioflg;
685 args.args.vop_args.vp = vp;
686 error = vn_io_fault1(vp, &auio, &args, td);
687 } else if (rw == UIO_READ) {
688 error = VOP_READ(vp, &auio, ioflg, cred);
689 } else /* if (rw == UIO_WRITE) */ {
690 error = VOP_WRITE(vp, &auio, ioflg, cred);
691 }
692 }
693 if (aresid)
694 *aresid = auio.uio_resid;
695 else
696 if (auio.uio_resid && error == 0)
697 error = EIO;
698 if ((ioflg & IO_NODELOCKED) == 0) {
699 VOP_UNLOCK(vp);
700 if (mp != NULL)
701 vn_finished_write(mp);
702 }
703 out:
704 if (rl_cookie != NULL)
705 vn_rangelock_unlock(vp, rl_cookie);
706 return (error);
707}
708
709/*
710 * Package up an I/O request on a vnode into a uio and do it. The I/O
711 * request is split up into smaller chunks and we try to avoid saturating
712 * the buffer cache while potentially holding a vnode locked, so we
713 * check bwillwrite() before calling vn_rdwr(). We also call kern_yield()
714 * to give other processes a chance to lock the vnode (either other processes
715 * core'ing the same binary, or unrelated processes scanning the directory).
716 */
717int
718vn_rdwr_inchunks(enum uio_rw rw, struct vnode *vp, void *base, size_t len,
719 off_t offset, enum uio_seg segflg, int ioflg, struct ucred *active_cred,
720 struct ucred *file_cred, size_t *aresid, struct thread *td)
721{
722 int error = 0;
723 ssize_t iaresid;
724
725 do {
726 int chunk;
727
728 /*
729 * Force `offset' to a multiple of MAXBSIZE except possibly
730 * for the first chunk, so that filesystems only need to
731 * write full blocks except possibly for the first and last
732 * chunks.
733 */
734 chunk = MAXBSIZE - (uoff_t)offset % MAXBSIZE;
735
736 if (chunk > len)
737 chunk = len;
738 if (rw != UIO_READ && vp->v_type == VREG)
739 bwillwrite();
740 iaresid = 0;
741 error = vn_rdwr(rw, vp, base, chunk, offset, segflg,
742 ioflg, active_cred, file_cred, &iaresid, td);
743 len -= chunk; /* aresid calc already includes length */
744 if (error)
745 break;
746 offset += chunk;
747 base = (char *)base + chunk;
748 kern_yield(PRI_USER);
749 } while (len);
750 if (aresid)
751 *aresid = len + iaresid;
752 return (error);
753}
754
755#if OFF_MAX <= LONG_MAX
756off_t
757foffset_lock(struct file *fp, int flags)
758{
759 volatile short *flagsp;
760 off_t res;
761 short state;
762
763 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
764
765 if ((flags & FOF_NOLOCK) != 0)
766 return (atomic_load_long(&fp->f_offset));
767
768 /*
769 * According to McKusick the vn lock was protecting f_offset here.
770 * It is now protected by the FOFFSET_LOCKED flag.
771 */
772 flagsp = &fp->f_vnread_flags;
773 if (atomic_cmpset_acq_16(flagsp, 0, FOFFSET_LOCKED))
774 return (atomic_load_long(&fp->f_offset));
775
776 sleepq_lock(&fp->f_vnread_flags);
777 state = atomic_load_16(flagsp);
778 for (;;) {
779 if ((state & FOFFSET_LOCKED) == 0) {
780 if (!atomic_fcmpset_acq_16(flagsp, &state,
781 FOFFSET_LOCKED))
782 continue;
783 break;
784 }
785 if ((state & FOFFSET_LOCK_WAITING) == 0) {
786 if (!atomic_fcmpset_acq_16(flagsp, &state,
787 state | FOFFSET_LOCK_WAITING))
788 continue;
789 }
790 DROP_GIANT();
791 sleepq_add(&fp->f_vnread_flags, NULL, "vofflock", 0, 0);
792 sleepq_wait(&fp->f_vnread_flags, PUSER -1);
793 PICKUP_GIANT();
794 sleepq_lock(&fp->f_vnread_flags);
795 state = atomic_load_16(flagsp);
796 }
797 res = atomic_load_long(&fp->f_offset);
798 sleepq_release(&fp->f_vnread_flags);
799 return (res);
800}
801
802void
803foffset_unlock(struct file *fp, off_t val, int flags)
804{
805 volatile short *flagsp;
806 short state;
807
808 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
809
810 if ((flags & FOF_NOUPDATE) == 0)
811 atomic_store_long(&fp->f_offset, val);
812 if ((flags & FOF_NEXTOFF_R) != 0)
813 fp->f_nextoff[UIO_READ] = val;
814 if ((flags & FOF_NEXTOFF_W) != 0)
815 fp->f_nextoff[UIO_WRITE] = val;
816
817 if ((flags & FOF_NOLOCK) != 0)
818 return;
819
820 flagsp = &fp->f_vnread_flags;
821 state = atomic_load_16(flagsp);
822 if ((state & FOFFSET_LOCK_WAITING) == 0 &&
823 atomic_cmpset_rel_16(flagsp, state, 0))
824 return;
825
826 sleepq_lock(&fp->f_vnread_flags);
827 MPASS((fp->f_vnread_flags & FOFFSET_LOCKED) != 0);
828 MPASS((fp->f_vnread_flags & FOFFSET_LOCK_WAITING) != 0);
829 fp->f_vnread_flags = 0;
830 sleepq_broadcast(&fp->f_vnread_flags, SLEEPQ_SLEEP, 0, 0);
831 sleepq_release(&fp->f_vnread_flags);
832}
833#else
834off_t
835foffset_lock(struct file *fp, int flags)
836{
837 struct mtx *mtxp;
838 off_t res;
839
840 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
841
842 mtxp = mtx_pool_find(mtxpool_sleep, fp);
843 mtx_lock(mtxp);
844 if ((flags & FOF_NOLOCK) == 0) {
845 while (fp->f_vnread_flags & FOFFSET_LOCKED) {
846 fp->f_vnread_flags |= FOFFSET_LOCK_WAITING;
847 msleep(&fp->f_vnread_flags, mtxp, PUSER -1,
848 "vofflock", 0);
849 }
850 fp->f_vnread_flags |= FOFFSET_LOCKED;
851 }
852 res = fp->f_offset;
853 mtx_unlock(mtxp);
854 return (res);
855}
856
857void
858foffset_unlock(struct file *fp, off_t val, int flags)
859{
860 struct mtx *mtxp;
861
862 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
863
864 mtxp = mtx_pool_find(mtxpool_sleep, fp);
865 mtx_lock(mtxp);
866 if ((flags & FOF_NOUPDATE) == 0)
867 fp->f_offset = val;
868 if ((flags & FOF_NEXTOFF_R) != 0)
869 fp->f_nextoff[UIO_READ] = val;
870 if ((flags & FOF_NEXTOFF_W) != 0)
871 fp->f_nextoff[UIO_WRITE] = val;
872 if ((flags & FOF_NOLOCK) == 0) {
873 KASSERT((fp->f_vnread_flags & FOFFSET_LOCKED) != 0,
874 ("Lost FOFFSET_LOCKED"));
875 if (fp->f_vnread_flags & FOFFSET_LOCK_WAITING)
876 wakeup(&fp->f_vnread_flags);
877 fp->f_vnread_flags = 0;
878 }
879 mtx_unlock(mtxp);
880}
881#endif
882
883void
884foffset_lock_uio(struct file *fp, struct uio *uio, int flags)
885{
886
887 if ((flags & FOF_OFFSET) == 0)
888 uio->uio_offset = foffset_lock(fp, flags);
889}
890
891void
892foffset_unlock_uio(struct file *fp, struct uio *uio, int flags)
893{
894
895 if ((flags & FOF_OFFSET) == 0)
896 foffset_unlock(fp, uio->uio_offset, flags);
897}
898
899static int
900get_advice(struct file *fp, struct uio *uio)
901{
902 struct mtx *mtxp;
903 int ret;
904
905 ret = POSIX_FADV_NORMAL;
906 if (fp->f_advice == NULL || fp->f_vnode->v_type != VREG)
907 return (ret);
908
909 mtxp = mtx_pool_find(mtxpool_sleep, fp);
910 mtx_lock(mtxp);
911 if (fp->f_advice != NULL &&
912 uio->uio_offset >= fp->f_advice->fa_start &&
913 uio->uio_offset + uio->uio_resid <= fp->f_advice->fa_end)
914 ret = fp->f_advice->fa_advice;
915 mtx_unlock(mtxp);
916 return (ret);
917}
918
919static int
920get_write_ioflag(struct file *fp)
921{
922 int ioflag;
923 struct mount *mp;
924 struct vnode *vp;
925
926 ioflag = 0;
927 vp = fp->f_vnode;
928 mp = atomic_load_ptr(&vp->v_mount);
929
930 if ((fp->f_flag & O_DIRECT) != 0)
931 ioflag |= IO_DIRECT;
932
933 if ((fp->f_flag & O_FSYNC) != 0 ||
934 (mp != NULL && (mp->mnt_flag & MNT_SYNCHRONOUS) != 0))
935 ioflag |= IO_SYNC;
936
937 /*
938 * For O_DSYNC we set both IO_SYNC and IO_DATASYNC, so that VOP_WRITE()
939 * or VOP_DEALLOCATE() implementations that don't understand IO_DATASYNC
940 * fall back to full O_SYNC behavior.
941 */
942 if ((fp->f_flag & O_DSYNC) != 0)
943 ioflag |= IO_SYNC | IO_DATASYNC;
944
945 return (ioflag);
946}
947
948int
949vn_read_from_obj(struct vnode *vp, struct uio *uio)
950{
951 vm_object_t obj;
952 vm_page_t ma[io_hold_cnt + 2];
953 off_t off, vsz;
954 ssize_t resid;
955 int error, i, j;
956
957 MPASS(uio->uio_resid <= ptoa(io_hold_cnt + 2));
958 obj = atomic_load_ptr(&vp->v_object);
959 if (obj == NULL)
960 return (EJUSTRETURN);
961
962 /*
963 * Depends on type stability of vm_objects.
964 */
965 vm_object_pip_add(obj, 1);
966 if ((obj->flags & OBJ_DEAD) != 0) {
967 /*
968 * Note that object might be already reused from the
969 * vnode, and the OBJ_DEAD flag cleared. This is fine,
970 * we recheck for DOOMED vnode state after all pages
971 * are busied, and retract then.
972 *
973 * But we check for OBJ_DEAD to ensure that we do not
974 * busy pages while vm_object_terminate_pages()
975 * processes the queue.
976 */
977 error = EJUSTRETURN;
978 goto out_pip;
979 }
980
981 resid = uio->uio_resid;
982 off = uio->uio_offset;
983 for (i = 0; resid > 0; i++) {
984 MPASS(i < io_hold_cnt + 2);
985 ma[i] = vm_page_grab_unlocked(obj, atop(off),
986 VM_ALLOC_NOCREAT | VM_ALLOC_SBUSY | VM_ALLOC_IGN_SBUSY |
987 VM_ALLOC_NOWAIT);
988 if (ma[i] == NULL)
989 break;
990
991 /*
992 * Skip invalid pages. Valid mask can be partial only
993 * at EOF, and we clip later.
994 */
995 if (vm_page_none_valid(ma[i])) {
996 vm_page_sunbusy(ma[i]);
997 break;
998 }
999
1000 resid -= PAGE_SIZE;
1001 off += PAGE_SIZE;
1002 }
1003 if (i == 0) {
1004 error = EJUSTRETURN;
1005 goto out_pip;
1006 }
1007
1008 /*
1009 * Check VIRF_DOOMED after we busied our pages. Since
1010 * vgonel() terminates the vnode' vm_object, it cannot
1011 * process past pages busied by us.
1012 */
1013 if (VN_IS_DOOMED(vp)) {
1014 error = EJUSTRETURN;
1015 goto out;
1016 }
1017
1018 resid = PAGE_SIZE - (uio->uio_offset & PAGE_MASK) + ptoa(i - 1);
1019 if (resid > uio->uio_resid)
1020 resid = uio->uio_resid;
1021
1022 /*
1023 * Unlocked read of vnp_size is safe because truncation cannot
1024 * pass busied page. But we load vnp_size into a local
1025 * variable so that possible concurrent extension does not
1026 * break calculation.
1027 */
1028#if defined(__powerpc__) && !defined(__powerpc64__)
1029 vsz = obj->un_pager.vnp.vnp_size;
1030#else
1031 vsz = atomic_load_64(&obj->un_pager.vnp.vnp_size);
1032#endif
1033 if (uio->uio_offset >= vsz) {
1034 error = EJUSTRETURN;
1035 goto out;
1036 }
1037 if (uio->uio_offset + resid > vsz)
1038 resid = vsz - uio->uio_offset;
1039
1040 error = vn_io_fault_pgmove(ma, uio->uio_offset & PAGE_MASK, resid, uio);
1041
1042out:
1043 for (j = 0; j < i; j++) {
1044 if (error == 0)
1045 vm_page_reference(ma[j]);
1046 vm_page_sunbusy(ma[j]);
1047 }
1048out_pip:
1049 vm_object_pip_wakeup(obj);
1050 if (error != 0)
1051 return (error);
1052 return (uio->uio_resid == 0 ? 0 : EJUSTRETURN);
1053}
1054
1055/*
1056 * File table vnode read routine.
1057 */
1058static int
1059vn_read(struct file *fp, struct uio *uio, struct ucred *active_cred, int flags,
1060 struct thread *td)
1061{
1062 struct vnode *vp;
1063 off_t orig_offset;
1064 int error, ioflag;
1065 int advice;
1066
1067 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
1068 uio->uio_td, td));
1069 KASSERT(flags & FOF_OFFSET, ("No FOF_OFFSET"));
1070 vp = fp->f_vnode;
1071 ioflag = 0;
1072 if (fp->f_flag & FNONBLOCK)
1073 ioflag |= IO_NDELAY;
1074 if (fp->f_flag & O_DIRECT)
1075 ioflag |= IO_DIRECT;
1076
1077 /*
1078 * Try to read from page cache. VIRF_DOOMED check is racy but
1079 * allows us to avoid unneeded work outright.
1080 */
1081 if (vn_io_pgcache_read_enable && !mac_vnode_check_read_enabled() &&
1082 (vn_irflag_read(vp) & (VIRF_DOOMED | VIRF_PGREAD)) == VIRF_PGREAD) {
1083 error = VOP_READ_PGCACHE(vp, uio, ioflag, fp->f_cred);
1084 if (error == 0) {
1085 fp->f_nextoff[UIO_READ] = uio->uio_offset;
1086 return (0);
1087 }
1088 if (error != EJUSTRETURN)
1089 return (error);
1090 }
1091
1092 advice = get_advice(fp, uio);
1093 vn_lock(vp, LK_SHARED | LK_RETRY);
1094
1095 switch (advice) {
1096 case POSIX_FADV_NORMAL:
1097 case POSIX_FADV_SEQUENTIAL:
1098 case POSIX_FADV_NOREUSE:
1099 ioflag |= sequential_heuristic(uio, fp);
1100 break;
1101 case POSIX_FADV_RANDOM:
1102 /* Disable read-ahead for random I/O. */
1103 break;
1104 }
1105 orig_offset = uio->uio_offset;
1106
1107#ifdef MAC
1108 error = mac_vnode_check_read(active_cred, fp->f_cred, vp);
1109 if (error == 0)
1110#endif
1111 error = VOP_READ(vp, uio, ioflag, fp->f_cred);
1112 fp->f_nextoff[UIO_READ] = uio->uio_offset;
1113 VOP_UNLOCK(vp);
1114 if (error == 0 && advice == POSIX_FADV_NOREUSE &&
1115 orig_offset != uio->uio_offset)
1116 /*
1117 * Use POSIX_FADV_DONTNEED to flush pages and buffers
1118 * for the backing file after a POSIX_FADV_NOREUSE
1119 * read(2).
1120 */
1121 error = VOP_ADVISE(vp, orig_offset, uio->uio_offset - 1,
1122 POSIX_FADV_DONTNEED);
1123 return (error);
1124}
1125
1126/*
1127 * File table vnode write routine.
1128 */
1129static int
1130vn_write(struct file *fp, struct uio *uio, struct ucred *active_cred, int flags,
1131 struct thread *td)
1132{
1133 struct vnode *vp;
1134 struct mount *mp;
1135 off_t orig_offset;
1136 int error, ioflag;
1137 int advice;
1138 bool need_finished_write;
1139
1140 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
1141 uio->uio_td, td));
1142 KASSERT(flags & FOF_OFFSET, ("No FOF_OFFSET"));
1143 vp = fp->f_vnode;
1144 if (vp->v_type == VREG)
1145 bwillwrite();
1146 ioflag = IO_UNIT;
1147 if (vp->v_type == VREG && (fp->f_flag & O_APPEND) != 0)
1148 ioflag |= IO_APPEND;
1149 if ((fp->f_flag & FNONBLOCK) != 0)
1150 ioflag |= IO_NDELAY;
1151 ioflag |= get_write_ioflag(fp);
1152
1153 mp = NULL;
1154 need_finished_write = false;
1155 if (vp->v_type != VCHR) {
1156 error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
1157 if (error != 0)
1158 goto unlock;
1159 need_finished_write = true;
1160 }
1161
1162 advice = get_advice(fp, uio);
1163
1164 vn_lock(vp, vn_lktype_write(mp, vp) | LK_RETRY);
1165 switch (advice) {
1166 case POSIX_FADV_NORMAL:
1167 case POSIX_FADV_SEQUENTIAL:
1168 case POSIX_FADV_NOREUSE:
1169 ioflag |= sequential_heuristic(uio, fp);
1170 break;
1171 case POSIX_FADV_RANDOM:
1172 /* XXX: Is this correct? */
1173 break;
1174 }
1175 orig_offset = uio->uio_offset;
1176
1177#ifdef MAC
1178 error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
1179 if (error == 0)
1180#endif
1181 error = VOP_WRITE(vp, uio, ioflag, fp->f_cred);
1182 fp->f_nextoff[UIO_WRITE] = uio->uio_offset;
1183 VOP_UNLOCK(vp);
1184 if (need_finished_write)
1185 vn_finished_write(mp);
1186 if (error == 0 && advice == POSIX_FADV_NOREUSE &&
1187 orig_offset != uio->uio_offset)
1188 /*
1189 * Use POSIX_FADV_DONTNEED to flush pages and buffers
1190 * for the backing file after a POSIX_FADV_NOREUSE
1191 * write(2).
1192 */
1193 error = VOP_ADVISE(vp, orig_offset, uio->uio_offset - 1,
1194 POSIX_FADV_DONTNEED);
1195unlock:
1196 return (error);
1197}
1198
1199/*
1200 * The vn_io_fault() is a wrapper around vn_read() and vn_write() to
1201 * prevent the following deadlock:
1202 *
1203 * Assume that the thread A reads from the vnode vp1 into userspace
1204 * buffer buf1 backed by the pages of vnode vp2. If a page in buf1 is
1205 * currently not resident, then system ends up with the call chain
1206 * vn_read() -> VOP_READ(vp1) -> uiomove() -> [Page Fault] ->
1207 * vm_fault(buf1) -> vnode_pager_getpages(vp2) -> VOP_GETPAGES(vp2)
1208 * which establishes lock order vp1->vn_lock, then vp2->vn_lock.
1209 * If, at the same time, thread B reads from vnode vp2 into buffer buf2
1210 * backed by the pages of vnode vp1, and some page in buf2 is not
1211 * resident, we get a reversed order vp2->vn_lock, then vp1->vn_lock.
1212 *
1213 * To prevent the lock order reversal and deadlock, vn_io_fault() does
1214 * not allow page faults to happen during VOP_READ() or VOP_WRITE().
1215 * Instead, it first tries to do the whole range i/o with pagefaults
1216 * disabled. If all pages in the i/o buffer are resident and mapped,
1217 * VOP will succeed (ignoring the genuine filesystem errors).
1218 * Otherwise, we get back EFAULT, and vn_io_fault() falls back to do
1219 * i/o in chunks, with all pages in the chunk prefaulted and held
1220 * using vm_fault_quick_hold_pages().
1221 *
1222 * Filesystems using this deadlock avoidance scheme should use the
1223 * array of the held pages from uio, saved in the curthread->td_ma,
1224 * instead of doing uiomove(). A helper function
1225 * vn_io_fault_uiomove() converts uiomove request into
1226 * uiomove_fromphys() over td_ma array.
1227 *
1228 * Since vnode locks do not cover the whole i/o anymore, rangelocks
1229 * make the current i/o request atomic with respect to other i/os and
1230 * truncations.
1231 */
1232
1233/*
1234 * Decode vn_io_fault_args and perform the corresponding i/o.
1235 */
1236static int
1237vn_io_fault_doio(struct vn_io_fault_args *args, struct uio *uio,
1238 struct thread *td)
1239{
1240 int error, save;
1241
1242 error = 0;
1243 save = vm_fault_disable_pagefaults();
1244 switch (args->kind) {
1245 case VN_IO_FAULT_FOP:
1246 error = (args->args.fop_args.doio)(args->args.fop_args.fp,
1247 uio, args->cred, args->flags, td);
1248 break;
1249 case VN_IO_FAULT_VOP:
1250 if (uio->uio_rw == UIO_READ) {
1251 error = VOP_READ(args->args.vop_args.vp, uio,
1252 args->flags, args->cred);
1253 } else if (uio->uio_rw == UIO_WRITE) {
1254 error = VOP_WRITE(args->args.vop_args.vp, uio,
1255 args->flags, args->cred);
1256 }
1257 break;
1258 default:
1259 panic("vn_io_fault_doio: unknown kind of io %d %d",
1260 args->kind, uio->uio_rw);
1261 }
1262 vm_fault_enable_pagefaults(save);
1263 return (error);
1264}
1265
1266static int
1267vn_io_fault_touch(char *base, const struct uio *uio)
1268{
1269 int r;
1270
1271 r = fubyte(base);
1272 if (r == -1 || (uio->uio_rw == UIO_READ && subyte(base, r) == -1))
1273 return (EFAULT);
1274 return (0);
1275}
1276
1277static int
1278vn_io_fault_prefault_user(const struct uio *uio)
1279{
1280 char *base;
1281 const struct iovec *iov;
1282 size_t len;
1283 ssize_t resid;
1284 int error, i;
1285
1286 KASSERT(uio->uio_segflg == UIO_USERSPACE,
1287 ("vn_io_fault_prefault userspace"));
1288
1289 error = i = 0;
1290 iov = uio->uio_iov;
1291 resid = uio->uio_resid;
1292 base = iov->iov_base;
1293 len = iov->iov_len;
1294 while (resid > 0) {
1295 error = vn_io_fault_touch(base, uio);
1296 if (error != 0)
1297 break;
1298 if (len < PAGE_SIZE) {
1299 if (len != 0) {
1300 error = vn_io_fault_touch(base + len - 1, uio);
1301 if (error != 0)
1302 break;
1303 resid -= len;
1304 }
1305 if (++i >= uio->uio_iovcnt)
1306 break;
1307 iov = uio->uio_iov + i;
1308 base = iov->iov_base;
1309 len = iov->iov_len;
1310 } else {
1311 len -= PAGE_SIZE;
1312 base += PAGE_SIZE;
1313 resid -= PAGE_SIZE;
1314 }
1315 }
1316 return (error);
1317}
1318
1319/*
1320 * Common code for vn_io_fault(), agnostic to the kind of i/o request.
1321 * Uses vn_io_fault_doio() to make the call to an actual i/o function.
1322 * Used from vn_rdwr() and vn_io_fault(), which encode the i/o request
1323 * into args and call vn_io_fault1() to handle faults during the user
1324 * mode buffer accesses.
1325 */
1326static int
1327vn_io_fault1(struct vnode *vp, struct uio *uio, struct vn_io_fault_args *args,
1328 struct thread *td)
1329{
1330 vm_page_t ma[io_hold_cnt + 2];
1331 struct uio *uio_clone, short_uio;
1332 struct iovec short_iovec[1];
1333 vm_page_t *prev_td_ma;
1334 vm_prot_t prot;
1335 vm_offset_t addr, end;
1336 size_t len, resid;
1337 ssize_t adv;
1338 int error, cnt, saveheld, prev_td_ma_cnt;
1339
1340 if (vn_io_fault_prefault) {
1341 error = vn_io_fault_prefault_user(uio);
1342 if (error != 0)
1343 return (error); /* Or ignore ? */
1344 }
1345
1346 prot = uio->uio_rw == UIO_READ ? VM_PROT_WRITE : VM_PROT_READ;
1347
1348 /*
1349 * The UFS follows IO_UNIT directive and replays back both
1350 * uio_offset and uio_resid if an error is encountered during the
1351 * operation. But, since the iovec may be already advanced,
1352 * uio is still in an inconsistent state.
1353 *
1354 * Cache a copy of the original uio, which is advanced to the redo
1355 * point using UIO_NOCOPY below.
1356 */
1357 uio_clone = cloneuio(uio);
1358 resid = uio->uio_resid;
1359
1360 short_uio.uio_segflg = UIO_USERSPACE;
1361 short_uio.uio_rw = uio->uio_rw;
1362 short_uio.uio_td = uio->uio_td;
1363
1364 error = vn_io_fault_doio(args, uio, td);
1365 if (error != EFAULT)
1366 goto out;
1367
1368 atomic_add_long(&vn_io_faults_cnt, 1);
1369 uio_clone->uio_segflg = UIO_NOCOPY;
1370 uiomove(NULL, resid - uio->uio_resid, uio_clone);
1371 uio_clone->uio_segflg = uio->uio_segflg;
1372
1373 saveheld = curthread_pflags_set(TDP_UIOHELD);
1374 prev_td_ma = td->td_ma;
1375 prev_td_ma_cnt = td->td_ma_cnt;
1376
1377 while (uio_clone->uio_resid != 0) {
1378 len = uio_clone->uio_iov->iov_len;
1379 if (len == 0) {
1380 KASSERT(uio_clone->uio_iovcnt >= 1,
1381 ("iovcnt underflow"));
1382 uio_clone->uio_iov++;
1383 uio_clone->uio_iovcnt--;
1384 continue;
1385 }
1386 if (len > ptoa(io_hold_cnt))
1387 len = ptoa(io_hold_cnt);
1388 addr = (uintptr_t)uio_clone->uio_iov->iov_base;
1389 end = round_page(addr + len);
1390 if (end < addr) {
1391 error = EFAULT;
1392 break;
1393 }
1394 cnt = atop(end - trunc_page(addr));
1395 /*
1396 * A perfectly misaligned address and length could cause
1397 * both the start and the end of the chunk to use partial
1398 * page. +2 accounts for such a situation.
1399 */
1400 cnt = vm_fault_quick_hold_pages(&td->td_proc->p_vmspace->vm_map,
1401 addr, len, prot, ma, io_hold_cnt + 2);
1402 if (cnt == -1) {
1403 error = EFAULT;
1404 break;
1405 }
1406 short_uio.uio_iov = &short_iovec[0];
1407 short_iovec[0].iov_base = (void *)addr;
1408 short_uio.uio_iovcnt = 1;
1409 short_uio.uio_resid = short_iovec[0].iov_len = len;
1410 short_uio.uio_offset = uio_clone->uio_offset;
1411 td->td_ma = ma;
1412 td->td_ma_cnt = cnt;
1413
1414 error = vn_io_fault_doio(args, &short_uio, td);
1415 vm_page_unhold_pages(ma, cnt);
1416 adv = len - short_uio.uio_resid;
1417
1418 uio_clone->uio_iov->iov_base =
1419 (char *)uio_clone->uio_iov->iov_base + adv;
1420 uio_clone->uio_iov->iov_len -= adv;
1421 uio_clone->uio_resid -= adv;
1422 uio_clone->uio_offset += adv;
1423
1424 uio->uio_resid -= adv;
1425 uio->uio_offset += adv;
1426
1427 if (error != 0 || adv == 0)
1428 break;
1429 }
1430 td->td_ma = prev_td_ma;
1431 td->td_ma_cnt = prev_td_ma_cnt;
1432 curthread_pflags_restore(saveheld);
1433out:
1434 free(uio_clone, M_IOV);
1435 return (error);
1436}
1437
1438static int
1439vn_io_fault(struct file *fp, struct uio *uio, struct ucred *active_cred,
1440 int flags, struct thread *td)
1441{
1442 fo_rdwr_t *doio;
1443 struct vnode *vp;
1444 void *rl_cookie;
1445 struct vn_io_fault_args args;
1446 int error;
1447
1448 doio = uio->uio_rw == UIO_READ ? vn_read : vn_write;
1449 vp = fp->f_vnode;
1450
1451 /*
1452 * The ability to read(2) on a directory has historically been
1453 * allowed for all users, but this can and has been the source of
1454 * at least one security issue in the past. As such, it is now hidden
1455 * away behind a sysctl for those that actually need it to use it, and
1456 * restricted to root when it's turned on to make it relatively safe to
1457 * leave on for longer sessions of need.
1458 */
1459 if (vp->v_type == VDIR) {
1460 KASSERT(uio->uio_rw == UIO_READ,
1461 ("illegal write attempted on a directory"));
1462 if (!vfs_allow_read_dir)
1463 return (EISDIR);
1464 if ((error = priv_check(td, PRIV_VFS_READ_DIR)) != 0)
1465 return (EISDIR);
1466 }
1467
1468 foffset_lock_uio(fp, uio, flags);
1469 if (do_vn_io_fault(vp, uio)) {
1470 args.kind = VN_IO_FAULT_FOP;
1471 args.args.fop_args.fp = fp;
1472 args.args.fop_args.doio = doio;
1473 args.cred = active_cred;
1474 args.flags = flags | FOF_OFFSET;
1475 if (uio->uio_rw == UIO_READ) {
1476 rl_cookie = vn_rangelock_rlock(vp, uio->uio_offset,
1477 uio->uio_offset + uio->uio_resid);
1478 } else if ((fp->f_flag & O_APPEND) != 0 ||
1479 (flags & FOF_OFFSET) == 0) {
1480 /* For appenders, punt and lock the whole range. */
1481 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
1482 } else {
1483 rl_cookie = vn_rangelock_wlock(vp, uio->uio_offset,
1484 uio->uio_offset + uio->uio_resid);
1485 }
1486 error = vn_io_fault1(vp, uio, &args, td);
1487 vn_rangelock_unlock(vp, rl_cookie);
1488 } else {
1489 error = doio(fp, uio, active_cred, flags | FOF_OFFSET, td);
1490 }
1491 foffset_unlock_uio(fp, uio, flags);
1492 return (error);
1493}
1494
1495/*
1496 * Helper function to perform the requested uiomove operation using
1497 * the held pages for io->uio_iov[0].iov_base buffer instead of
1498 * copyin/copyout. Access to the pages with uiomove_fromphys()
1499 * instead of iov_base prevents page faults that could occur due to
1500 * pmap_collect() invalidating the mapping created by
1501 * vm_fault_quick_hold_pages(), or pageout daemon, page laundry or
1502 * object cleanup revoking the write access from page mappings.
1503 *
1504 * Filesystems specified MNTK_NO_IOPF shall use vn_io_fault_uiomove()
1505 * instead of plain uiomove().
1506 */
1507int
1508vn_io_fault_uiomove(char *data, int xfersize, struct uio *uio)
1509{
1510 struct uio transp_uio;
1511 struct iovec transp_iov[1];
1512 struct thread *td;
1513 size_t adv;
1514 int error, pgadv;
1515
1516 td = curthread;
1517 if ((td->td_pflags & TDP_UIOHELD) == 0 ||
1518 uio->uio_segflg != UIO_USERSPACE)
1519 return (uiomove(data, xfersize, uio));
1520
1521 KASSERT(uio->uio_iovcnt == 1, ("uio_iovcnt %d", uio->uio_iovcnt));
1522 transp_iov[0].iov_base = data;
1523 transp_uio.uio_iov = &transp_iov[0];
1524 transp_uio.uio_iovcnt = 1;
1525 if (xfersize > uio->uio_resid)
1526 xfersize = uio->uio_resid;
1527 transp_uio.uio_resid = transp_iov[0].iov_len = xfersize;
1528 transp_uio.uio_offset = 0;
1529 transp_uio.uio_segflg = UIO_SYSSPACE;
1530 /*
1531 * Since transp_iov points to data, and td_ma page array
1532 * corresponds to original uio->uio_iov, we need to invert the
1533 * direction of the i/o operation as passed to
1534 * uiomove_fromphys().
1535 */
1536 switch (uio->uio_rw) {
1537 case UIO_WRITE:
1538 transp_uio.uio_rw = UIO_READ;
1539 break;
1540 case UIO_READ:
1541 transp_uio.uio_rw = UIO_WRITE;
1542 break;
1543 }
1544 transp_uio.uio_td = uio->uio_td;
1545 error = uiomove_fromphys(td->td_ma,
1546 ((vm_offset_t)uio->uio_iov->iov_base) & PAGE_MASK,
1547 xfersize, &transp_uio);
1548 adv = xfersize - transp_uio.uio_resid;
1549 pgadv =
1550 (((vm_offset_t)uio->uio_iov->iov_base + adv) >> PAGE_SHIFT) -
1551 (((vm_offset_t)uio->uio_iov->iov_base) >> PAGE_SHIFT);
1552 td->td_ma += pgadv;
1553 KASSERT(td->td_ma_cnt >= pgadv, ("consumed pages %d %d", td->td_ma_cnt,
1554 pgadv));
1555 td->td_ma_cnt -= pgadv;
1556 uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + adv;
1557 uio->uio_iov->iov_len -= adv;
1558 uio->uio_resid -= adv;
1559 uio->uio_offset += adv;
1560 return (error);
1561}
1562
1563int
1564vn_io_fault_pgmove(vm_page_t ma[], vm_offset_t offset, int xfersize,
1565 struct uio *uio)
1566{
1567 struct thread *td;
1568 vm_offset_t iov_base;
1569 int cnt, pgadv;
1570
1571 td = curthread;
1572 if ((td->td_pflags & TDP_UIOHELD) == 0 ||
1573 uio->uio_segflg != UIO_USERSPACE)
1574 return (uiomove_fromphys(ma, offset, xfersize, uio));
1575
1576 KASSERT(uio->uio_iovcnt == 1, ("uio_iovcnt %d", uio->uio_iovcnt));
1577 cnt = xfersize > uio->uio_resid ? uio->uio_resid : xfersize;
1578 iov_base = (vm_offset_t)uio->uio_iov->iov_base;
1579 switch (uio->uio_rw) {
1580 case UIO_WRITE:
1581 pmap_copy_pages(td->td_ma, iov_base & PAGE_MASK, ma,
1582 offset, cnt);
1583 break;
1584 case UIO_READ:
1585 pmap_copy_pages(ma, offset, td->td_ma, iov_base & PAGE_MASK,
1586 cnt);
1587 break;
1588 }
1589 pgadv = ((iov_base + cnt) >> PAGE_SHIFT) - (iov_base >> PAGE_SHIFT);
1590 td->td_ma += pgadv;
1591 KASSERT(td->td_ma_cnt >= pgadv, ("consumed pages %d %d", td->td_ma_cnt,
1592 pgadv));
1593 td->td_ma_cnt -= pgadv;
1594 uio->uio_iov->iov_base = (char *)(iov_base + cnt);
1595 uio->uio_iov->iov_len -= cnt;
1596 uio->uio_resid -= cnt;
1597 uio->uio_offset += cnt;
1598 return (0);
1599}
1600
1601/*
1602 * File table truncate routine.
1603 */
1604static int
1605vn_truncate(struct file *fp, off_t length, struct ucred *active_cred,
1606 struct thread *td)
1607{
1608 struct mount *mp;
1609 struct vnode *vp;
1610 void *rl_cookie;
1611 int error;
1612
1613 vp = fp->f_vnode;
1614
1615retry:
1616 /*
1617 * Lock the whole range for truncation. Otherwise split i/o
1618 * might happen partly before and partly after the truncation.
1619 */
1620 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
1621 error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
1622 if (error)
1623 goto out1;
1624 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1625 AUDIT_ARG_VNODE1(vp);
1626 if (vp->v_type == VDIR) {
1627 error = EISDIR;
1628 goto out;
1629 }
1630#ifdef MAC
1631 error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
1632 if (error)
1633 goto out;
1634#endif
1635 error = vn_truncate_locked(vp, length, (fp->f_flag & O_FSYNC) != 0,
1636 fp->f_cred);
1637out:
1638 VOP_UNLOCK(vp);
1639 vn_finished_write(mp);
1640out1:
1641 vn_rangelock_unlock(vp, rl_cookie);
1642 if (error == ERELOOKUP)
1643 goto retry;
1644 return (error);
1645}
1646
1647/*
1648 * Truncate a file that is already locked.
1649 */
1650int
1651vn_truncate_locked(struct vnode *vp, off_t length, bool sync,
1652 struct ucred *cred)
1653{
1654 struct vattr vattr;
1655 int error;
1656
1657 error = VOP_ADD_WRITECOUNT(vp, 1);
1658 if (error == 0) {
1659 VATTR_NULL(&vattr);
1660 vattr.va_size = length;
1661 if (sync)
1662 vattr.va_vaflags |= VA_SYNC;
1663 error = VOP_SETATTR(vp, &vattr, cred);
1664 VOP_ADD_WRITECOUNT_CHECKED(vp, -1);
1665 }
1666 return (error);
1667}
1668
1669/*
1670 * File table vnode stat routine.
1671 */
1672int
1673vn_statfile(struct file *fp, struct stat *sb, struct ucred *active_cred)
1674{
1675 struct vnode *vp = fp->f_vnode;
1676 int error;
1677
1678 vn_lock(vp, LK_SHARED | LK_RETRY);
1679 error = VOP_STAT(vp, sb, active_cred, fp->f_cred);
1680 VOP_UNLOCK(vp);
1681
1682 return (error);
1683}
1684
1685/*
1686 * File table vnode ioctl routine.
1687 */
1688static int
1689vn_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred,
1690 struct thread *td)
1691{
1692 struct vattr vattr;
1693 struct vnode *vp;
1694 struct fiobmap2_arg *bmarg;
1695 int error;
1696
1697 vp = fp->f_vnode;
1698 switch (vp->v_type) {
1699 case VDIR:
1700 case VREG:
1701 switch (com) {
1702 case FIONREAD:
1703 vn_lock(vp, LK_SHARED | LK_RETRY);
1704 error = VOP_GETATTR(vp, &vattr, active_cred);
1705 VOP_UNLOCK(vp);
1706 if (error == 0)
1707 *(int *)data = vattr.va_size - fp->f_offset;
1708 return (error);
1709 case FIOBMAP2:
1710 bmarg = (struct fiobmap2_arg *)data;
1711 vn_lock(vp, LK_SHARED | LK_RETRY);
1712#ifdef MAC
1713 error = mac_vnode_check_read(active_cred, fp->f_cred,
1714 vp);
1715 if (error == 0)
1716#endif
1717 error = VOP_BMAP(vp, bmarg->bn, NULL,
1718 &bmarg->bn, &bmarg->runp, &bmarg->runb);
1719 VOP_UNLOCK(vp);
1720 return (error);
1721 case FIONBIO:
1722 case FIOASYNC:
1723 return (0);
1724 default:
1725 return (VOP_IOCTL(vp, com, data, fp->f_flag,
1726 active_cred, td));
1727 }
1728 break;
1729 case VCHR:
1730 return (VOP_IOCTL(vp, com, data, fp->f_flag,
1731 active_cred, td));
1732 default:
1733 return (ENOTTY);
1734 }
1735}
1736
1737/*
1738 * File table vnode poll routine.
1739 */
1740static int
1741vn_poll(struct file *fp, int events, struct ucred *active_cred,
1742 struct thread *td)
1743{
1744 struct vnode *vp;
1745 int error;
1746
1747 vp = fp->f_vnode;
1748#if defined(MAC) || defined(AUDIT)
1749 if (AUDITING_TD(td) || mac_vnode_check_poll_enabled()) {
1750 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1751 AUDIT_ARG_VNODE1(vp);
1752 error = mac_vnode_check_poll(active_cred, fp->f_cred, vp);
1753 VOP_UNLOCK(vp);
1754 if (error != 0)
1755 return (error);
1756 }
1757#endif
1758 error = VOP_POLL(vp, events, fp->f_cred, td);
1759 return (error);
1760}
1761
1762/*
1763 * Acquire the requested lock and then check for validity. LK_RETRY
1764 * permits vn_lock to return doomed vnodes.
1765 */
1766static int __noinline
1767_vn_lock_fallback(struct vnode *vp, int flags, const char *file, int line,
1768 int error)
1769{
1770
1771 KASSERT((flags & LK_RETRY) == 0 || error == 0,
1772 ("vn_lock: error %d incompatible with flags %#x", error, flags));
1773
1774 if (error == 0)
1775 VNASSERT(VN_IS_DOOMED(vp), vp, ("vnode not doomed"));
1776
1777 if ((flags & LK_RETRY) == 0) {
1778 if (error == 0) {
1779 VOP_UNLOCK(vp);
1780 error = ENOENT;
1781 }
1782 return (error);
1783 }
1784
1785 /*
1786 * LK_RETRY case.
1787 *
1788 * Nothing to do if we got the lock.
1789 */
1790 if (error == 0)
1791 return (0);
1792
1793 /*
1794 * Interlock was dropped by the call in _vn_lock.
1795 */
1796 flags &= ~LK_INTERLOCK;
1797 do {
1798 error = VOP_LOCK1(vp, flags, file, line);
1799 } while (error != 0);
1800 return (0);
1801}
1802
1803int
1804_vn_lock(struct vnode *vp, int flags, const char *file, int line)
1805{
1806 int error;
1807
1808 VNASSERT((flags & LK_TYPE_MASK) != 0, vp,
1809 ("vn_lock: no locktype (%d passed)", flags));
1810 VNPASS(vp->v_holdcnt > 0, vp);
1811 error = VOP_LOCK1(vp, flags, file, line);
1812 if (__predict_false(error != 0 || VN_IS_DOOMED(vp)))
1813 return (_vn_lock_fallback(vp, flags, file, line, error));
1814 return (0);
1815}
1816
1817/*
1818 * File table vnode close routine.
1819 */
1820static int
1821vn_closefile(struct file *fp, struct thread *td)
1822{
1823 struct vnode *vp;
1824 struct flock lf;
1825 int error;
1826 bool ref;
1827
1828 vp = fp->f_vnode;
1829 fp->f_ops = &badfileops;
1830 ref = (fp->f_flag & FHASLOCK) != 0;
1831
1832 error = vn_close1(vp, fp->f_flag, fp->f_cred, td, ref);
1833
1834 if (__predict_false(ref)) {
1835 lf.l_whence = SEEK_SET;
1836 lf.l_start = 0;
1837 lf.l_len = 0;
1838 lf.l_type = F_UNLCK;
1839 (void) VOP_ADVLOCK(vp, fp, F_UNLCK, &lf, F_FLOCK);
1840 vrele(vp);
1841 }
1842 return (error);
1843}
1844
1845/*
1846 * Preparing to start a filesystem write operation. If the operation is
1847 * permitted, then we bump the count of operations in progress and
1848 * proceed. If a suspend request is in progress, we wait until the
1849 * suspension is over, and then proceed.
1850 */
1851static int
1852vn_start_write_refed(struct mount *mp, int flags, bool mplocked)
1853{
1854 struct mount_pcpu *mpcpu;
1855 int error, mflags;
1856
1857 if (__predict_true(!mplocked) && (flags & V_XSLEEP) == 0 &&
1858 vfs_op_thread_enter(mp, mpcpu)) {
1859 MPASS((mp->mnt_kern_flag & MNTK_SUSPEND) == 0);
1860 vfs_mp_count_add_pcpu(mpcpu, writeopcount, 1);
1861 vfs_op_thread_exit(mp, mpcpu);
1862 return (0);
1863 }
1864
1865 if (mplocked)
1866 mtx_assert(MNT_MTX(mp), MA_OWNED);
1867 else
1868 MNT_ILOCK(mp);
1869
1870 error = 0;
1871
1872 /*
1873 * Check on status of suspension.
1874 */
1875 if ((curthread->td_pflags & TDP_IGNSUSP) == 0 ||
1876 mp->mnt_susp_owner != curthread) {
1877 mflags = ((mp->mnt_vfc->vfc_flags & VFCF_SBDRY) != 0 ?
1878 (flags & PCATCH) : 0) | (PUSER - 1);
1879 while ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
1880 if (flags & V_NOWAIT) {
1881 error = EWOULDBLOCK;
1882 goto unlock;
1883 }
1884 error = msleep(&mp->mnt_flag, MNT_MTX(mp), mflags,
1885 "suspfs", 0);
1886 if (error)
1887 goto unlock;
1888 }
1889 }
1890 if (flags & V_XSLEEP)
1891 goto unlock;
1892 mp->mnt_writeopcount++;
1893unlock:
1894 if (error != 0 || (flags & V_XSLEEP) != 0)
1895 MNT_REL(mp);
1896 MNT_IUNLOCK(mp);
1897 return (error);
1898}
1899
1900int
1901vn_start_write(struct vnode *vp, struct mount **mpp, int flags)
1902{
1903 struct mount *mp;
1904 int error;
1905
1906 KASSERT((flags & V_MNTREF) == 0 || (*mpp != NULL && vp == NULL),
1907 ("V_MNTREF requires mp"));
1908
1909 error = 0;
1910 /*
1911 * If a vnode is provided, get and return the mount point that
1912 * to which it will write.
1913 */
1914 if (vp != NULL) {
1915 if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
1916 *mpp = NULL;
1917 if (error != EOPNOTSUPP)
1918 return (error);
1919 return (0);
1920 }
1921 }
1922 if ((mp = *mpp) == NULL)
1923 return (0);
1924
1925 /*
1926 * VOP_GETWRITEMOUNT() returns with the mp refcount held through
1927 * a vfs_ref().
1928 * As long as a vnode is not provided we need to acquire a
1929 * refcount for the provided mountpoint too, in order to
1930 * emulate a vfs_ref().
1931 */
1932 if (vp == NULL && (flags & V_MNTREF) == 0)
1933 vfs_ref(mp);
1934
1935 return (vn_start_write_refed(mp, flags, false));
1936}
1937
1938/*
1939 * Secondary suspension. Used by operations such as vop_inactive
1940 * routines that are needed by the higher level functions. These
1941 * are allowed to proceed until all the higher level functions have
1942 * completed (indicated by mnt_writeopcount dropping to zero). At that
1943 * time, these operations are halted until the suspension is over.
1944 */
1945int
1946vn_start_secondary_write(struct vnode *vp, struct mount **mpp, int flags)
1947{
1948 struct mount *mp;
1949 int error;
1950
1951 KASSERT((flags & V_MNTREF) == 0 || (*mpp != NULL && vp == NULL),
1952 ("V_MNTREF requires mp"));
1953
1954 retry:
1955 if (vp != NULL) {
1956 if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
1957 *mpp = NULL;
1958 if (error != EOPNOTSUPP)
1959 return (error);
1960 return (0);
1961 }
1962 }
1963 /*
1964 * If we are not suspended or have not yet reached suspended
1965 * mode, then let the operation proceed.
1966 */
1967 if ((mp = *mpp) == NULL)
1968 return (0);
1969
1970 /*
1971 * VOP_GETWRITEMOUNT() returns with the mp refcount held through
1972 * a vfs_ref().
1973 * As long as a vnode is not provided we need to acquire a
1974 * refcount for the provided mountpoint too, in order to
1975 * emulate a vfs_ref().
1976 */
1977 MNT_ILOCK(mp);
1978 if (vp == NULL && (flags & V_MNTREF) == 0)
1979 MNT_REF(mp);
1980 if ((mp->mnt_kern_flag & (MNTK_SUSPENDED | MNTK_SUSPEND2)) == 0) {
1981 mp->mnt_secondary_writes++;
1982 mp->mnt_secondary_accwrites++;
1983 MNT_IUNLOCK(mp);
1984 return (0);
1985 }
1986 if (flags & V_NOWAIT) {
1987 MNT_REL(mp);
1988 MNT_IUNLOCK(mp);
1989 return (EWOULDBLOCK);
1990 }
1991 /*
1992 * Wait for the suspension to finish.
1993 */
1994 error = msleep(&mp->mnt_flag, MNT_MTX(mp), (PUSER - 1) | PDROP |
1995 ((mp->mnt_vfc->vfc_flags & VFCF_SBDRY) != 0 ? (flags & PCATCH) : 0),
1996 "suspfs", 0);
1997 vfs_rel(mp);
1998 if (error == 0)
1999 goto retry;
2000 return (error);
2001}
2002
2003/*
2004 * Filesystem write operation has completed. If we are suspending and this
2005 * operation is the last one, notify the suspender that the suspension is
2006 * now in effect.
2007 */
2008void
2009vn_finished_write(struct mount *mp)
2010{
2011 struct mount_pcpu *mpcpu;
2012 int c;
2013
2014 if (mp == NULL)
2015 return;
2016
2017 if (vfs_op_thread_enter(mp, mpcpu)) {
2018 vfs_mp_count_sub_pcpu(mpcpu, writeopcount, 1);
2019 vfs_mp_count_sub_pcpu(mpcpu, ref, 1);
2020 vfs_op_thread_exit(mp, mpcpu);
2021 return;
2022 }
2023
2024 MNT_ILOCK(mp);
2025 vfs_assert_mount_counters(mp);
2026 MNT_REL(mp);
2027 c = --mp->mnt_writeopcount;
2028 if (mp->mnt_vfs_ops == 0) {
2029 MPASS((mp->mnt_kern_flag & MNTK_SUSPEND) == 0);
2030 MNT_IUNLOCK(mp);
2031 return;
2032 }
2033 if (c < 0)
2034 vfs_dump_mount_counters(mp);
2035 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 && c == 0)
2036 wakeup(&mp->mnt_writeopcount);
2037 MNT_IUNLOCK(mp);
2038}
2039
2040/*
2041 * Filesystem secondary write operation has completed. If we are
2042 * suspending and this operation is the last one, notify the suspender
2043 * that the suspension is now in effect.
2044 */
2045void
2046vn_finished_secondary_write(struct mount *mp)
2047{
2048 if (mp == NULL)
2049 return;
2050 MNT_ILOCK(mp);
2051 MNT_REL(mp);
2052 mp->mnt_secondary_writes--;
2053 if (mp->mnt_secondary_writes < 0)
2054 panic("vn_finished_secondary_write: neg cnt");
2055 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 &&
2056 mp->mnt_secondary_writes <= 0)
2057 wakeup(&mp->mnt_secondary_writes);
2058 MNT_IUNLOCK(mp);
2059}
2060
2061/*
2062 * Request a filesystem to suspend write operations.
2063 */
2064int
2065vfs_write_suspend(struct mount *mp, int flags)
2066{
2067 int error;
2068
2069 vfs_op_enter(mp);
2070
2071 MNT_ILOCK(mp);
2072 vfs_assert_mount_counters(mp);
2073 if (mp->mnt_susp_owner == curthread) {
2074 vfs_op_exit_locked(mp);
2075 MNT_IUNLOCK(mp);
2076 return (EALREADY);
2077 }
2078 while (mp->mnt_kern_flag & MNTK_SUSPEND)
2079 msleep(&mp->mnt_flag, MNT_MTX(mp), PUSER - 1, "wsuspfs", 0);
2080
2081 /*
2082 * Unmount holds a write reference on the mount point. If we
2083 * own busy reference and drain for writers, we deadlock with
2084 * the reference draining in the unmount path. Callers of
2085 * vfs_write_suspend() must specify VS_SKIP_UNMOUNT if
2086 * vfs_busy() reference is owned and caller is not in the
2087 * unmount context.
2088 */
2089 if ((flags & VS_SKIP_UNMOUNT) != 0 &&
2090 (mp->mnt_kern_flag & MNTK_UNMOUNT) != 0) {
2091 vfs_op_exit_locked(mp);
2092 MNT_IUNLOCK(mp);
2093 return (EBUSY);
2094 }
2095
2096 mp->mnt_kern_flag |= MNTK_SUSPEND;
2097 mp->mnt_susp_owner = curthread;
2098 if (mp->mnt_writeopcount > 0)
2099 (void) msleep(&mp->mnt_writeopcount,
2100 MNT_MTX(mp), (PUSER - 1)|PDROP, "suspwt", 0);
2101 else
2102 MNT_IUNLOCK(mp);
2103 if ((error = VFS_SYNC(mp, MNT_SUSPEND)) != 0) {
2104 vfs_write_resume(mp, 0);
2105 /* vfs_write_resume does vfs_op_exit() for us */
2106 }
2107 return (error);
2108}
2109
2110/*
2111 * Request a filesystem to resume write operations.
2112 */
2113void
2114vfs_write_resume(struct mount *mp, int flags)
2115{
2116
2117 MNT_ILOCK(mp);
2118 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
2119 KASSERT(mp->mnt_susp_owner == curthread, ("mnt_susp_owner"));
2120 mp->mnt_kern_flag &= ~(MNTK_SUSPEND | MNTK_SUSPEND2 |
2121 MNTK_SUSPENDED);
2122 mp->mnt_susp_owner = NULL;
2123 wakeup(&mp->mnt_writeopcount);
2124 wakeup(&mp->mnt_flag);
2125 curthread->td_pflags &= ~TDP_IGNSUSP;
2126 if ((flags & VR_START_WRITE) != 0) {
2127 MNT_REF(mp);
2128 mp->mnt_writeopcount++;
2129 }
2130 MNT_IUNLOCK(mp);
2131 if ((flags & VR_NO_SUSPCLR) == 0)
2132 VFS_SUSP_CLEAN(mp);
2133 vfs_op_exit(mp);
2134 } else if ((flags & VR_START_WRITE) != 0) {
2135 MNT_REF(mp);
2136 vn_start_write_refed(mp, 0, true);
2137 } else {
2138 MNT_IUNLOCK(mp);
2139 }
2140}
2141
2142/*
2143 * Helper loop around vfs_write_suspend() for filesystem unmount VFS
2144 * methods.
2145 */
2146int
2147vfs_write_suspend_umnt(struct mount *mp)
2148{
2149 int error;
2150
2151 KASSERT((curthread->td_pflags & TDP_IGNSUSP) == 0,
2152 ("vfs_write_suspend_umnt: recursed"));
2153
2154 /* dounmount() already called vn_start_write(). */
2155 for (;;) {
2156 vn_finished_write(mp);
2157 error = vfs_write_suspend(mp, 0);
2158 if (error != 0) {
2159 vn_start_write(NULL, &mp, V_WAIT);
2160 return (error);
2161 }
2162 MNT_ILOCK(mp);
2163 if ((mp->mnt_kern_flag & MNTK_SUSPENDED) != 0)
2164 break;
2165 MNT_IUNLOCK(mp);
2166 vn_start_write(NULL, &mp, V_WAIT);
2167 }
2168 mp->mnt_kern_flag &= ~(MNTK_SUSPENDED | MNTK_SUSPEND2);
2169 wakeup(&mp->mnt_flag);
2170 MNT_IUNLOCK(mp);
2171 curthread->td_pflags |= TDP_IGNSUSP;
2172 return (0);
2173}
2174
2175/*
2176 * Implement kqueues for files by translating it to vnode operation.
2177 */
2178static int
2179vn_kqfilter(struct file *fp, struct knote *kn)
2180{
2181
2182 return (VOP_KQFILTER(fp->f_vnode, kn));
2183}
2184
2185int
2186vn_kqfilter_opath(struct file *fp, struct knote *kn)
2187{
2188 if ((fp->f_flag & FKQALLOWED) == 0)
2189 return (EBADF);
2190 return (vn_kqfilter(fp, kn));
2191}
2192
2193/*
2194 * Simplified in-kernel wrapper calls for extended attribute access.
2195 * Both calls pass in a NULL credential, authorizing as "kernel" access.
2196 * Set IO_NODELOCKED in ioflg if the vnode is already locked.
2197 */
2198int
2199vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace,
2200 const char *attrname, int *buflen, char *buf, struct thread *td)
2201{
2202 struct uio auio;
2203 struct iovec iov;
2204 int error;
2205
2206 iov.iov_len = *buflen;
2207 iov.iov_base = buf;
2208
2209 auio.uio_iov = &iov;
2210 auio.uio_iovcnt = 1;
2211 auio.uio_rw = UIO_READ;
2212 auio.uio_segflg = UIO_SYSSPACE;
2213 auio.uio_td = td;
2214 auio.uio_offset = 0;
2215 auio.uio_resid = *buflen;
2216
2217 if ((ioflg & IO_NODELOCKED) == 0)
2218 vn_lock(vp, LK_SHARED | LK_RETRY);
2219
2220 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
2221
2222 /* authorize attribute retrieval as kernel */
2223 error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL,
2224 td);
2225
2226 if ((ioflg & IO_NODELOCKED) == 0)
2227 VOP_UNLOCK(vp);
2228
2229 if (error == 0) {
2230 *buflen = *buflen - auio.uio_resid;
2231 }
2232
2233 return (error);
2234}
2235
2236/*
2237 * XXX failure mode if partially written?
2238 */
2239int
2240vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace,
2241 const char *attrname, int buflen, char *buf, struct thread *td)
2242{
2243 struct uio auio;
2244 struct iovec iov;
2245 struct mount *mp;
2246 int error;
2247
2248 iov.iov_len = buflen;
2249 iov.iov_base = buf;
2250
2251 auio.uio_iov = &iov;
2252 auio.uio_iovcnt = 1;
2253 auio.uio_rw = UIO_WRITE;
2254 auio.uio_segflg = UIO_SYSSPACE;
2255 auio.uio_td = td;
2256 auio.uio_offset = 0;
2257 auio.uio_resid = buflen;
2258
2259 if ((ioflg & IO_NODELOCKED) == 0) {
2260 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
2261 return (error);
2262 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2263 }
2264
2265 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
2266
2267 /* authorize attribute setting as kernel */
2268 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, td);
2269
2270 if ((ioflg & IO_NODELOCKED) == 0) {
2271 vn_finished_write(mp);
2272 VOP_UNLOCK(vp);
2273 }
2274
2275 return (error);
2276}
2277
2278int
2279vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace,
2280 const char *attrname, struct thread *td)
2281{
2282 struct mount *mp;
2283 int error;
2284
2285 if ((ioflg & IO_NODELOCKED) == 0) {
2286 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
2287 return (error);
2288 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2289 }
2290
2291 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
2292
2293 /* authorize attribute removal as kernel */
2294 error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL, td);
2295 if (error == EOPNOTSUPP)
2296 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL,
2297 NULL, td);
2298
2299 if ((ioflg & IO_NODELOCKED) == 0) {
2300 vn_finished_write(mp);
2301 VOP_UNLOCK(vp);
2302 }
2303
2304 return (error);
2305}
2306
2307static int
2308vn_get_ino_alloc_vget(struct mount *mp, void *arg, int lkflags,
2309 struct vnode **rvp)
2310{
2311
2312 return (VFS_VGET(mp, *(ino_t *)arg, lkflags, rvp));
2313}
2314
2315int
2316vn_vget_ino(struct vnode *vp, ino_t ino, int lkflags, struct vnode **rvp)
2317{
2318
2319 return (vn_vget_ino_gen(vp, vn_get_ino_alloc_vget, &ino,
2320 lkflags, rvp));
2321}
2322
2323int
2324vn_vget_ino_gen(struct vnode *vp, vn_get_ino_t alloc, void *alloc_arg,
2325 int lkflags, struct vnode **rvp)
2326{
2327 struct mount *mp;
2328 int ltype, error;
2329
2330 ASSERT_VOP_LOCKED(vp, "vn_vget_ino_get");
2331 mp = vp->v_mount;
2332 ltype = VOP_ISLOCKED(vp);
2333 KASSERT(ltype == LK_EXCLUSIVE || ltype == LK_SHARED,
2334 ("vn_vget_ino: vp not locked"));
2335 error = vfs_busy(mp, MBF_NOWAIT);
2336 if (error != 0) {
2337 vfs_ref(mp);
2338 VOP_UNLOCK(vp);
2339 error = vfs_busy(mp, 0);
2340 vn_lock(vp, ltype | LK_RETRY);
2341 vfs_rel(mp);
2342 if (error != 0)
2343 return (ENOENT);
2344 if (VN_IS_DOOMED(vp)) {
2345 vfs_unbusy(mp);
2346 return (ENOENT);
2347 }
2348 }
2349 VOP_UNLOCK(vp);
2350 error = alloc(mp, alloc_arg, lkflags, rvp);
2351 vfs_unbusy(mp);
2352 if (error != 0 || *rvp != vp)
2353 vn_lock(vp, ltype | LK_RETRY);
2354 if (VN_IS_DOOMED(vp)) {
2355 if (error == 0) {
2356 if (*rvp == vp)
2357 vunref(vp);
2358 else
2359 vput(*rvp);
2360 }
2361 error = ENOENT;
2362 }
2363 return (error);
2364}
2365
2366int
2367vn_rlimit_fsize(const struct vnode *vp, const struct uio *uio,
2368 struct thread *td)
2369{
2370 off_t lim;
2371 bool ktr_write;
2372
2373 if (td == NULL)
2374 return (0);
2375
2376 /*
2377 * There are conditions where the limit is to be ignored.
2378 * However, since it is almost never reached, check it first.
2379 */
2380 ktr_write = (td->td_pflags & TDP_INKTRACE) != 0;
2381 lim = lim_cur(td, RLIMIT_FSIZE);
2382 if (__predict_false(ktr_write))
2383 lim = td->td_ktr_io_lim;
2384 if (__predict_true((uoff_t)uio->uio_offset + uio->uio_resid <= lim))
2385 return (0);
2386
2387 /*
2388 * The limit is reached.
2389 */
2390 if (vp->v_type != VREG ||
2391 (td->td_pflags2 & TDP2_ACCT) != 0)
2392 return (0);
2393
2394 if (!ktr_write || ktr_filesize_limit_signal) {
2395 PROC_LOCK(td->td_proc);
2396 kern_psignal(td->td_proc, SIGXFSZ);
2397 PROC_UNLOCK(td->td_proc);
2398 }
2399 return (EFBIG);
2400}
2401
2402int
2403vn_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
2404 struct thread *td)
2405{
2406 struct vnode *vp;
2407
2408 vp = fp->f_vnode;
2409#ifdef AUDIT
2410 vn_lock(vp, LK_SHARED | LK_RETRY);
2411 AUDIT_ARG_VNODE1(vp);
2412 VOP_UNLOCK(vp);
2413#endif
2414 return (setfmode(td, active_cred, vp, mode));
2415}
2416
2417int
2418vn_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
2419 struct thread *td)
2420{
2421 struct vnode *vp;
2422
2423 vp = fp->f_vnode;
2424#ifdef AUDIT
2425 vn_lock(vp, LK_SHARED | LK_RETRY);
2426 AUDIT_ARG_VNODE1(vp);
2427 VOP_UNLOCK(vp);
2428#endif
2429 return (setfown(td, active_cred, vp, uid, gid));
2430}
2431
2432/*
2433 * Remove pages in the range ["start", "end") from the vnode's VM object. If
2434 * "end" is 0, then the range extends to the end of the object.
2435 */
2436void
2437vn_pages_remove(struct vnode *vp, vm_pindex_t start, vm_pindex_t end)
2438{
2439 vm_object_t object;
2440
2441 if ((object = vp->v_object) == NULL)
2442 return;
2443 VM_OBJECT_WLOCK(object);
2444 vm_object_page_remove(object, start, end, 0);
2445 VM_OBJECT_WUNLOCK(object);
2446}
2447
2448/*
2449 * Like vn_pages_remove(), but skips invalid pages, which by definition are not
2450 * mapped into any process' address space. Filesystems may use this in
2451 * preference to vn_pages_remove() to avoid blocking on pages busied in
2452 * preparation for a VOP_GETPAGES.
2453 */
2454void
2455vn_pages_remove_valid(struct vnode *vp, vm_pindex_t start, vm_pindex_t end)
2456{
2457 vm_object_t object;
2458
2459 if ((object = vp->v_object) == NULL)
2460 return;
2461 VM_OBJECT_WLOCK(object);
2462 vm_object_page_remove(object, start, end, OBJPR_VALIDONLY);
2463 VM_OBJECT_WUNLOCK(object);
2464}
2465
2466int
2467vn_bmap_seekhole_locked(struct vnode *vp, u_long cmd, off_t *off,
2468 struct ucred *cred)
2469{
2470 struct vattr va;
2471 daddr_t bn, bnp;
2472 uint64_t bsize;
2473 off_t noff;
2474 int error;
2475
2476 KASSERT(cmd == FIOSEEKHOLE || cmd == FIOSEEKDATA,
2477 ("%s: Wrong command %lu", __func__, cmd));
2478 ASSERT_VOP_LOCKED(vp, "vn_bmap_seekhole_locked");
2479
2480 if (vp->v_type != VREG) {
2481 error = ENOTTY;
2482 goto out;
2483 }
2484 error = VOP_GETATTR(vp, &va, cred);
2485 if (error != 0)
2486 goto out;
2487 noff = *off;
2488 if (noff >= va.va_size) {
2489 error = ENXIO;
2490 goto out;
2491 }
2492 bsize = vp->v_mount->mnt_stat.f_iosize;
2493 for (bn = noff / bsize; noff < va.va_size; bn++, noff += bsize -
2494 noff % bsize) {
2495 error = VOP_BMAP(vp, bn, NULL, &bnp, NULL, NULL);
2496 if (error == EOPNOTSUPP) {
2497 error = ENOTTY;
2498 goto out;
2499 }
2500 if ((bnp == -1 && cmd == FIOSEEKHOLE) ||
2501 (bnp != -1 && cmd == FIOSEEKDATA)) {
2502 noff = bn * bsize;
2503 if (noff < *off)
2504 noff = *off;
2505 goto out;
2506 }
2507 }
2508 if (noff > va.va_size)
2509 noff = va.va_size;
2510 /* noff == va.va_size. There is an implicit hole at the end of file. */
2511 if (cmd == FIOSEEKDATA)
2512 error = ENXIO;
2513out:
2514 if (error == 0)
2515 *off = noff;
2516 return (error);
2517}
2518
2519int
2520vn_bmap_seekhole(struct vnode *vp, u_long cmd, off_t *off, struct ucred *cred)
2521{
2522 int error;
2523
2524 KASSERT(cmd == FIOSEEKHOLE || cmd == FIOSEEKDATA,
2525 ("%s: Wrong command %lu", __func__, cmd));
2526
2527 if (vn_lock(vp, LK_SHARED) != 0)
2528 return (EBADF);
2529 error = vn_bmap_seekhole_locked(vp, cmd, off, cred);
2530 VOP_UNLOCK(vp);
2531 return (error);
2532}
2533
2534int
2535vn_seek(struct file *fp, off_t offset, int whence, struct thread *td)
2536{
2537 struct ucred *cred;
2538 struct vnode *vp;
2539 struct vattr vattr;
2540 off_t foffset, size;
2541 int error, noneg;
2542
2543 cred = td->td_ucred;
2544 vp = fp->f_vnode;
2545 foffset = foffset_lock(fp, 0);
2546 noneg = (vp->v_type != VCHR);
2547 error = 0;
2548 switch (whence) {
2549 case L_INCR:
2550 if (noneg &&
2551 (foffset < 0 ||
2552 (offset > 0 && foffset > OFF_MAX - offset))) {
2553 error = EOVERFLOW;
2554 break;
2555 }
2556 offset += foffset;
2557 break;
2558 case L_XTND:
2559 vn_lock(vp, LK_SHARED | LK_RETRY);
2560 error = VOP_GETATTR(vp, &vattr, cred);
2561 VOP_UNLOCK(vp);
2562 if (error)
2563 break;
2564
2565 /*
2566 * If the file references a disk device, then fetch
2567 * the media size and use that to determine the ending
2568 * offset.
2569 */
2570 if (vattr.va_size == 0 && vp->v_type == VCHR &&
2571 fo_ioctl(fp, DIOCGMEDIASIZE, &size, cred, td) == 0)
2572 vattr.va_size = size;
2573 if (noneg &&
2574 (vattr.va_size > OFF_MAX ||
2575 (offset > 0 && vattr.va_size > OFF_MAX - offset))) {
2576 error = EOVERFLOW;
2577 break;
2578 }
2579 offset += vattr.va_size;
2580 break;
2581 case L_SET:
2582 break;
2583 case SEEK_DATA:
2584 error = fo_ioctl(fp, FIOSEEKDATA, &offset, cred, td);
2585 if (error == ENOTTY)
2586 error = EINVAL;
2587 break;
2588 case SEEK_HOLE:
2589 error = fo_ioctl(fp, FIOSEEKHOLE, &offset, cred, td);
2590 if (error == ENOTTY)
2591 error = EINVAL;
2592 break;
2593 default:
2594 error = EINVAL;
2595 }
2596 if (error == 0 && noneg && offset < 0)
2597 error = EINVAL;
2598 if (error != 0)
2599 goto drop;
2600 VFS_KNOTE_UNLOCKED(vp, 0);
2601 td->td_uretoff.tdu_off = offset;
2602drop:
2603 foffset_unlock(fp, offset, error != 0 ? FOF_NOUPDATE : 0);
2604 return (error);
2605}
2606
2607int
2608vn_utimes_perm(struct vnode *vp, struct vattr *vap, struct ucred *cred,
2609 struct thread *td)
2610{
2611 int error;
2612
2613 /*
2614 * Grant permission if the caller is the owner of the file, or
2615 * the super-user, or has ACL_WRITE_ATTRIBUTES permission on
2616 * on the file. If the time pointer is null, then write
2617 * permission on the file is also sufficient.
2618 *
2619 * From NFSv4.1, draft 21, 6.2.1.3.1, Discussion of Mask Attributes:
2620 * A user having ACL_WRITE_DATA or ACL_WRITE_ATTRIBUTES
2621 * will be allowed to set the times [..] to the current
2622 * server time.
2623 */
2624 error = VOP_ACCESSX(vp, VWRITE_ATTRIBUTES, cred, td);
2625 if (error != 0 && (vap->va_vaflags & VA_UTIMES_NULL) != 0)
2626 error = VOP_ACCESS(vp, VWRITE, cred, td);
2627 return (error);
2628}
2629
2630int
2631vn_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
2632{
2633 struct vnode *vp;
2634 int error;
2635
2636 if (fp->f_type == DTYPE_FIFO)
2637 kif->kf_type = KF_TYPE_FIFO;
2638 else
2639 kif->kf_type = KF_TYPE_VNODE;
2640 vp = fp->f_vnode;
2641 vref(vp);
2642 FILEDESC_SUNLOCK(fdp);
2643 error = vn_fill_kinfo_vnode(vp, kif);
2644 vrele(vp);
2645 FILEDESC_SLOCK(fdp);
2646 return (error);
2647}
2648
2649static inline void
2650vn_fill_junk(struct kinfo_file *kif)
2651{
2652 size_t len, olen;
2653
2654 /*
2655 * Simulate vn_fullpath returning changing values for a given
2656 * vp during e.g. coredump.
2657 */
2658 len = (arc4random() % (sizeof(kif->kf_path) - 2)) + 1;
2659 olen = strlen(kif->kf_path);
2660 if (len < olen)
2661 strcpy(&kif->kf_path[len - 1], "$");
2662 else
2663 for (; olen < len; olen++)
2664 strcpy(&kif->kf_path[olen], "A");
2665}
2666
2667int
2668vn_fill_kinfo_vnode(struct vnode *vp, struct kinfo_file *kif)
2669{
2670 struct vattr va;
2671 char *fullpath, *freepath;
2672 int error;
2673
2674 kif->kf_un.kf_file.kf_file_type = vntype_to_kinfo(vp->v_type);
2675 freepath = NULL;
2676 fullpath = "-";
2677 error = vn_fullpath(vp, &fullpath, &freepath);
2678 if (error == 0) {
2679 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path));
2680 }
2681 if (freepath != NULL)
2682 free(freepath, M_TEMP);
2683
2684 KFAIL_POINT_CODE(DEBUG_FP, fill_kinfo_vnode__random_path,
2685 vn_fill_junk(kif);
2686 );
2687
2688 /*
2689 * Retrieve vnode attributes.
2690 */
2691 va.va_fsid = VNOVAL;
2692 va.va_rdev = NODEV;
2693 vn_lock(vp, LK_SHARED | LK_RETRY);
2694 error = VOP_GETATTR(vp, &va, curthread->td_ucred);
2695 VOP_UNLOCK(vp);
2696 if (error != 0)
2697 return (error);
2698 if (va.va_fsid != VNOVAL)
2699 kif->kf_un.kf_file.kf_file_fsid = va.va_fsid;
2700 else
2701 kif->kf_un.kf_file.kf_file_fsid =
2702 vp->v_mount->mnt_stat.f_fsid.val[0];
2703 kif->kf_un.kf_file.kf_file_fsid_freebsd11 =
2704 kif->kf_un.kf_file.kf_file_fsid; /* truncate */
2705 kif->kf_un.kf_file.kf_file_fileid = va.va_fileid;
2706 kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode);
2707 kif->kf_un.kf_file.kf_file_size = va.va_size;
2708 kif->kf_un.kf_file.kf_file_rdev = va.va_rdev;
2709 kif->kf_un.kf_file.kf_file_rdev_freebsd11 =
2710 kif->kf_un.kf_file.kf_file_rdev; /* truncate */
2711 return (0);
2712}
2713
2714int
2715vn_mmap(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t size,
2716 vm_prot_t prot, vm_prot_t cap_maxprot, int flags, vm_ooffset_t foff,
2717 struct thread *td)
2718{
2719#ifdef HWPMC_HOOKS
2720 struct pmckern_map_in pkm;
2721#endif
2722 struct mount *mp;
2723 struct vnode *vp;
2724 vm_object_t object;
2725 vm_prot_t maxprot;
2726 boolean_t writecounted;
2727 int error;
2728
2729#if defined(COMPAT_FREEBSD7) || defined(COMPAT_FREEBSD6) || \
2730 defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4)
2731 /*
2732 * POSIX shared-memory objects are defined to have
2733 * kernel persistence, and are not defined to support
2734 * read(2)/write(2) -- or even open(2). Thus, we can
2735 * use MAP_ASYNC to trade on-disk coherence for speed.
2736 * The shm_open(3) library routine turns on the FPOSIXSHM
2737 * flag to request this behavior.
2738 */
2739 if ((fp->f_flag & FPOSIXSHM) != 0)
2740 flags |= MAP_NOSYNC;
2741#endif
2742 vp = fp->f_vnode;
2743
2744 /*
2745 * Ensure that file and memory protections are
2746 * compatible. Note that we only worry about
2747 * writability if mapping is shared; in this case,
2748 * current and max prot are dictated by the open file.
2749 * XXX use the vnode instead? Problem is: what
2750 * credentials do we use for determination? What if
2751 * proc does a setuid?
2752 */
2753 mp = vp->v_mount;
2754 if (mp != NULL && (mp->mnt_flag & MNT_NOEXEC) != 0) {
2755 maxprot = VM_PROT_NONE;
2756 if ((prot & VM_PROT_EXECUTE) != 0)
2757 return (EACCES);
2758 } else
2759 maxprot = VM_PROT_EXECUTE;
2760 if ((fp->f_flag & FREAD) != 0)
2761 maxprot |= VM_PROT_READ;
2762 else if ((prot & VM_PROT_READ) != 0)
2763 return (EACCES);
2764
2765 /*
2766 * If we are sharing potential changes via MAP_SHARED and we
2767 * are trying to get write permission although we opened it
2768 * without asking for it, bail out.
2769 */
2770 if ((flags & MAP_SHARED) != 0) {
2771 if ((fp->f_flag & FWRITE) != 0)
2772 maxprot |= VM_PROT_WRITE;
2773 else if ((prot & VM_PROT_WRITE) != 0)
2774 return (EACCES);
2775 } else {
2776 maxprot |= VM_PROT_WRITE;
2777 cap_maxprot |= VM_PROT_WRITE;
2778 }
2779 maxprot &= cap_maxprot;
2780
2781 /*
2782 * For regular files and shared memory, POSIX requires that
2783 * the value of foff be a legitimate offset within the data
2784 * object. In particular, negative offsets are invalid.
2785 * Blocking negative offsets and overflows here avoids
2786 * possible wraparound or user-level access into reserved
2787 * ranges of the data object later. In contrast, POSIX does
2788 * not dictate how offsets are used by device drivers, so in
2789 * the case of a device mapping a negative offset is passed
2790 * on.
2791 */
2792 if (
2793#ifdef _LP64
2794 size > OFF_MAX ||
2795#endif
2796 foff > OFF_MAX - size)
2797 return (EINVAL);
2798
2799 writecounted = FALSE;
2800 error = vm_mmap_vnode(td, size, prot, &maxprot, &flags, vp,
2801 &foff, &object, &writecounted);
2802 if (error != 0)
2803 return (error);
2804 error = vm_mmap_object(map, addr, size, prot, maxprot, flags, object,
2805 foff, writecounted, td);
2806 if (error != 0) {
2807 /*
2808 * If this mapping was accounted for in the vnode's
2809 * writecount, then undo that now.
2810 */
2811 if (writecounted)
2812 vm_pager_release_writecount(object, 0, size);
2813 vm_object_deallocate(object);
2814 }
2815#ifdef HWPMC_HOOKS
2816 /* Inform hwpmc(4) if an executable is being mapped. */
2817 if (PMC_HOOK_INSTALLED(PMC_FN_MMAP)) {
2818 if ((prot & VM_PROT_EXECUTE) != 0 && error == 0) {
2819 pkm.pm_file = vp;
2820 pkm.pm_address = (uintptr_t) *addr;
2821 PMC_CALL_HOOK_UNLOCKED(td, PMC_FN_MMAP, (void *) &pkm);
2822 }
2823 }
2824#endif
2825 return (error);
2826}
2827
2828void
2829vn_fsid(struct vnode *vp, struct vattr *va)
2830{
2831 fsid_t *f;
2832
2833 f = &vp->v_mount->mnt_stat.f_fsid;
2834 va->va_fsid = (uint32_t)f->val[1];
2835 va->va_fsid <<= sizeof(f->val[1]) * NBBY;
2836 va->va_fsid += (uint32_t)f->val[0];
2837}
2838
2839int
2840vn_fsync_buf(struct vnode *vp, int waitfor)
2841{
2842 struct buf *bp, *nbp;
2843 struct bufobj *bo;
2844 struct mount *mp;
2845 int error, maxretry;
2846
2847 error = 0;
2848 maxretry = 10000; /* large, arbitrarily chosen */
2849 mp = NULL;
2850 if (vp->v_type == VCHR) {
2851 VI_LOCK(vp);
2852 mp = vp->v_rdev->si_mountpt;
2853 VI_UNLOCK(vp);
2854 }
2855 bo = &vp->v_bufobj;
2856 BO_LOCK(bo);
2857loop1:
2858 /*
2859 * MARK/SCAN initialization to avoid infinite loops.
2860 */
2861 TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs) {
2862 bp->b_vflags &= ~BV_SCANNED;
2863 bp->b_error = 0;
2864 }
2865
2866 /*
2867 * Flush all dirty buffers associated with a vnode.
2868 */
2869loop2:
2870 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
2871 if ((bp->b_vflags & BV_SCANNED) != 0)
2872 continue;
2873 bp->b_vflags |= BV_SCANNED;
2874 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL)) {
2875 if (waitfor != MNT_WAIT)
2876 continue;
2877 if (BUF_LOCK(bp,
2878 LK_EXCLUSIVE | LK_INTERLOCK | LK_SLEEPFAIL,
2879 BO_LOCKPTR(bo)) != 0) {
2880 BO_LOCK(bo);
2881 goto loop1;
2882 }
2883 BO_LOCK(bo);
2884 }
2885 BO_UNLOCK(bo);
2886 KASSERT(bp->b_bufobj == bo,
2887 ("bp %p wrong b_bufobj %p should be %p",
2888 bp, bp->b_bufobj, bo));
2889 if ((bp->b_flags & B_DELWRI) == 0)
2890 panic("fsync: not dirty");
2891 if ((vp->v_object != NULL) && (bp->b_flags & B_CLUSTEROK)) {
2892 vfs_bio_awrite(bp);
2893 } else {
2894 bremfree(bp);
2895 bawrite(bp);
2896 }
2897 if (maxretry < 1000)
2898 pause("dirty", hz < 1000 ? 1 : hz / 1000);
2899 BO_LOCK(bo);
2900 goto loop2;
2901 }
2902
2903 /*
2904 * If synchronous the caller expects us to completely resolve all
2905 * dirty buffers in the system. Wait for in-progress I/O to
2906 * complete (which could include background bitmap writes), then
2907 * retry if dirty blocks still exist.
2908 */
2909 if (waitfor == MNT_WAIT) {
2910 bufobj_wwait(bo, 0, 0);
2911 if (bo->bo_dirty.bv_cnt > 0) {
2912 /*
2913 * If we are unable to write any of these buffers
2914 * then we fail now rather than trying endlessly
2915 * to write them out.
2916 */
2917 TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs)
2918 if ((error = bp->b_error) != 0)
2919 break;
2920 if ((mp != NULL && mp->mnt_secondary_writes > 0) ||
2921 (error == 0 && --maxretry >= 0))
2922 goto loop1;
2923 if (error == 0)
2924 error = EAGAIN;
2925 }
2926 }
2927 BO_UNLOCK(bo);
2928 if (error != 0)
2929 vn_printf(vp, "fsync: giving up on dirty (error = %d) ", error);
2930
2931 return (error);
2932}
2933
2934/*
2935 * Copies a byte range from invp to outvp. Calls VOP_COPY_FILE_RANGE()
2936 * or vn_generic_copy_file_range() after rangelocking the byte ranges,
2937 * to do the actual copy.
2938 * vn_generic_copy_file_range() is factored out, so it can be called
2939 * from a VOP_COPY_FILE_RANGE() call as well, but handles vnodes from
2940 * different file systems.
2941 */
2942int
2943vn_copy_file_range(struct vnode *invp, off_t *inoffp, struct vnode *outvp,
2944 off_t *outoffp, size_t *lenp, unsigned int flags, struct ucred *incred,
2945 struct ucred *outcred, struct thread *fsize_td)
2946{
2947 int error;
2948 size_t len;
2949 uint64_t uval;
2950
2951 len = *lenp;
2952 *lenp = 0; /* For error returns. */
2953 error = 0;
2954
2955 /* Do some sanity checks on the arguments. */
2956 if (invp->v_type == VDIR || outvp->v_type == VDIR)
2957 error = EISDIR;
2958 else if (*inoffp < 0 || *outoffp < 0 ||
2959 invp->v_type != VREG || outvp->v_type != VREG)
2960 error = EINVAL;
2961 if (error != 0)
2962 goto out;
2963
2964 /* Ensure offset + len does not wrap around. */
2965 uval = *inoffp;
2966 uval += len;
2967 if (uval > INT64_MAX)
2968 len = INT64_MAX - *inoffp;
2969 uval = *outoffp;
2970 uval += len;
2971 if (uval > INT64_MAX)
2972 len = INT64_MAX - *outoffp;
2973 if (len == 0)
2974 goto out;
2975
2976 /*
2977 * If the two vnode are for the same file system, call
2978 * VOP_COPY_FILE_RANGE(), otherwise call vn_generic_copy_file_range()
2979 * which can handle copies across multiple file systems.
2980 */
2981 *lenp = len;
2982 if (invp->v_mount == outvp->v_mount)
2983 error = VOP_COPY_FILE_RANGE(invp, inoffp, outvp, outoffp,
2984 lenp, flags, incred, outcred, fsize_td);
2985 else
2986 error = vn_generic_copy_file_range(invp, inoffp, outvp,
2987 outoffp, lenp, flags, incred, outcred, fsize_td);
2988out:
2989 return (error);
2990}
2991
2992/*
2993 * Test len bytes of data starting at dat for all bytes == 0.
2994 * Return true if all bytes are zero, false otherwise.
2995 * Expects dat to be well aligned.
2996 */
2997static bool
2998mem_iszero(void *dat, int len)
2999{
3000 int i;
3001 const u_int *p;
3002 const char *cp;
3003
3004 for (p = dat; len > 0; len -= sizeof(*p), p++) {
3005 if (len >= sizeof(*p)) {
3006 if (*p != 0)
3007 return (false);
3008 } else {
3009 cp = (const char *)p;
3010 for (i = 0; i < len; i++, cp++)
3011 if (*cp != '\0')
3012 return (false);
3013 }
3014 }
3015 return (true);
3016}
3017
3018/*
3019 * Look for a hole in the output file and, if found, adjust *outoffp
3020 * and *xferp to skip past the hole.
3021 * *xferp is the entire hole length to be written and xfer2 is how many bytes
3022 * to be written as 0's upon return.
3023 */
3024static off_t
3025vn_skip_hole(struct vnode *outvp, off_t xfer2, off_t *outoffp, off_t *xferp,
3026 off_t *dataoffp, off_t *holeoffp, struct ucred *cred)
3027{
3028 int error;
3029 off_t delta;
3030
3031 if (*holeoffp == 0 || *holeoffp <= *outoffp) {
3032 *dataoffp = *outoffp;
3033 error = VOP_IOCTL(outvp, FIOSEEKDATA, dataoffp, 0, cred,
3034 curthread);
3035 if (error == 0) {
3036 *holeoffp = *dataoffp;
3037 error = VOP_IOCTL(outvp, FIOSEEKHOLE, holeoffp, 0, cred,
3038 curthread);
3039 }
3040 if (error != 0 || *holeoffp == *dataoffp) {
3041 /*
3042 * Since outvp is unlocked, it may be possible for
3043 * another thread to do a truncate(), lseek(), write()
3044 * creating a hole at startoff between the above
3045 * VOP_IOCTL() calls, if the other thread does not do
3046 * rangelocking.
3047 * If that happens, *holeoffp == *dataoffp and finding
3048 * the hole has failed, so disable vn_skip_hole().
3049 */
3050 *holeoffp = -1; /* Disable use of vn_skip_hole(). */
3051 return (xfer2);
3052 }
3053 KASSERT(*dataoffp >= *outoffp,
3054 ("vn_skip_hole: dataoff=%jd < outoff=%jd",
3055 (intmax_t)*dataoffp, (intmax_t)*outoffp));
3056 KASSERT(*holeoffp > *dataoffp,
3057 ("vn_skip_hole: holeoff=%jd <= dataoff=%jd",
3058 (intmax_t)*holeoffp, (intmax_t)*dataoffp));
3059 }
3060
3061 /*
3062 * If there is a hole before the data starts, advance *outoffp and
3063 * *xferp past the hole.
3064 */
3065 if (*dataoffp > *outoffp) {
3066 delta = *dataoffp - *outoffp;
3067 if (delta >= *xferp) {
3068 /* Entire *xferp is a hole. */
3069 *outoffp += *xferp;
3070 *xferp = 0;
3071 return (0);
3072 }
3073 *xferp -= delta;
3074 *outoffp += delta;
3075 xfer2 = MIN(xfer2, *xferp);
3076 }
3077
3078 /*
3079 * If a hole starts before the end of this xfer2, reduce this xfer2 so
3080 * that the write ends at the start of the hole.
3081 * *holeoffp should always be greater than *outoffp, but for the
3082 * non-INVARIANTS case, check this to make sure xfer2 remains a sane
3083 * value.
3084 */
3085 if (*holeoffp > *outoffp && *holeoffp < *outoffp + xfer2)
3086 xfer2 = *holeoffp - *outoffp;
3087 return (xfer2);
3088}
3089
3090/*
3091 * Write an xfer sized chunk to outvp in blksize blocks from dat.
3092 * dat is a maximum of blksize in length and can be written repeatedly in
3093 * the chunk.
3094 * If growfile == true, just grow the file via vn_truncate_locked() instead
3095 * of doing actual writes.
3096 * If checkhole == true, a hole is being punched, so skip over any hole
3097 * already in the output file.
3098 */
3099static int
3100vn_write_outvp(struct vnode *outvp, char *dat, off_t outoff, off_t xfer,
3101 u_long blksize, bool growfile, bool checkhole, struct ucred *cred)
3102{
3103 struct mount *mp;
3104 off_t dataoff, holeoff, xfer2;
3105 int error;
3106
3107 /*
3108 * Loop around doing writes of blksize until write has been completed.
3109 * Lock/unlock on each loop iteration so that a bwillwrite() can be
3110 * done for each iteration, since the xfer argument can be very
3111 * large if there is a large hole to punch in the output file.
3112 */
3113 error = 0;
3114 holeoff = 0;
3115 do {
3116 xfer2 = MIN(xfer, blksize);
3117 if (checkhole) {
3118 /*
3119 * Punching a hole. Skip writing if there is
3120 * already a hole in the output file.
3121 */
3122 xfer2 = vn_skip_hole(outvp, xfer2, &outoff, &xfer,
3123 &dataoff, &holeoff, cred);
3124 if (xfer == 0)
3125 break;
3126 if (holeoff < 0)
3127 checkhole = false;
3128 KASSERT(xfer2 > 0, ("vn_write_outvp: xfer2=%jd",
3129 (intmax_t)xfer2));
3130 }
3131 bwillwrite();
3132 mp = NULL;
3133 error = vn_start_write(outvp, &mp, V_WAIT);
3134 if (error != 0)
3135 break;
3136 if (growfile) {
3137 error = vn_lock(outvp, LK_EXCLUSIVE);
3138 if (error == 0) {
3139 error = vn_truncate_locked(outvp, outoff + xfer,
3140 false, cred);
3141 VOP_UNLOCK(outvp);
3142 }
3143 } else {
3144 error = vn_lock(outvp, vn_lktype_write(mp, outvp));
3145 if (error == 0) {
3146 error = vn_rdwr(UIO_WRITE, outvp, dat, xfer2,
3147 outoff, UIO_SYSSPACE, IO_NODELOCKED,
3148 curthread->td_ucred, cred, NULL, curthread);
3149 outoff += xfer2;
3150 xfer -= xfer2;
3151 VOP_UNLOCK(outvp);
3152 }
3153 }
3154 if (mp != NULL)
3155 vn_finished_write(mp);
3156 } while (!growfile && xfer > 0 && error == 0);
3157 return (error);
3158}
3159
3160/*
3161 * Copy a byte range of one file to another. This function can handle the
3162 * case where invp and outvp are on different file systems.
3163 * It can also be called by a VOP_COPY_FILE_RANGE() to do the work, if there
3164 * is no better file system specific way to do it.
3165 */
3166int
3167vn_generic_copy_file_range(struct vnode *invp, off_t *inoffp,
3168 struct vnode *outvp, off_t *outoffp, size_t *lenp, unsigned int flags,
3169 struct ucred *incred, struct ucred *outcred, struct thread *fsize_td)
3170{
3171 struct vattr va, inva;
3172 struct mount *mp;
3173 struct uio io;
3174 off_t startoff, endoff, xfer, xfer2;
3175 u_long blksize;
3176 int error, interrupted;
3177 bool cantseek, readzeros, eof, lastblock, holetoeof;
3178 ssize_t aresid;
3179 size_t copylen, len, rem, savlen;
3180 char *dat;
3181 long holein, holeout;
3182 struct timespec curts, endts;
3183
3184 holein = holeout = 0;
3185 savlen = len = *lenp;
3186 error = 0;
3187 interrupted = 0;
3188 dat = NULL;
3189
3190 error = vn_lock(invp, LK_SHARED);
3191 if (error != 0)
3192 goto out;
3193 if (VOP_PATHCONF(invp, _PC_MIN_HOLE_SIZE, &holein) != 0)
3194 holein = 0;
3195 if (holein > 0)
3196 error = VOP_GETATTR(invp, &inva, incred);
3197 VOP_UNLOCK(invp);
3198 if (error != 0)
3199 goto out;
3200
3201 mp = NULL;
3202 error = vn_start_write(outvp, &mp, V_WAIT);
3203 if (error == 0)
3204 error = vn_lock(outvp, LK_EXCLUSIVE);
3205 if (error == 0) {
3206 /*
3207 * If fsize_td != NULL, do a vn_rlimit_fsize() call,
3208 * now that outvp is locked.
3209 */
3210 if (fsize_td != NULL) {
3211 io.uio_offset = *outoffp;
3212 io.uio_resid = len;
3213 error = vn_rlimit_fsize(outvp, &io, fsize_td);
3214 if (error != 0)
3215 error = EFBIG;
3216 }
3217 if (VOP_PATHCONF(outvp, _PC_MIN_HOLE_SIZE, &holeout) != 0)
3218 holeout = 0;
3219 /*
3220 * Holes that are past EOF do not need to be written as a block
3221 * of zero bytes. So, truncate the output file as far as
3222 * possible and then use va.va_size to decide if writing 0
3223 * bytes is necessary in the loop below.
3224 */
3225 if (error == 0)
3226 error = VOP_GETATTR(outvp, &va, outcred);
3227 if (error == 0 && va.va_size > *outoffp && va.va_size <=
3228 *outoffp + len) {
3229#ifdef MAC
3230 error = mac_vnode_check_write(curthread->td_ucred,
3231 outcred, outvp);
3232 if (error == 0)
3233#endif
3234 error = vn_truncate_locked(outvp, *outoffp,
3235 false, outcred);
3236 if (error == 0)
3237 va.va_size = *outoffp;
3238 }
3239 VOP_UNLOCK(outvp);
3240 }
3241 if (mp != NULL)
3242 vn_finished_write(mp);
3243 if (error != 0)
3244 goto out;
3245
3246 /*
3247 * Set the blksize to the larger of the hole sizes for invp and outvp.
3248 * If hole sizes aren't available, set the blksize to the larger
3249 * f_iosize of invp and outvp.
3250 * This code expects the hole sizes and f_iosizes to be powers of 2.
3251 * This value is clipped at 4Kbytes and 1Mbyte.
3252 */
3253 blksize = MAX(holein, holeout);
3254
3255 /* Clip len to end at an exact multiple of hole size. */
3256 if (blksize > 1) {
3257 rem = *inoffp % blksize;
3258 if (rem > 0)
3259 rem = blksize - rem;
3260 if (len > rem && len - rem > blksize)
3261 len = savlen = rounddown(len - rem, blksize) + rem;
3262 }
3263
3264 if (blksize <= 1)
3265 blksize = MAX(invp->v_mount->mnt_stat.f_iosize,
3266 outvp->v_mount->mnt_stat.f_iosize);
3267 if (blksize < 4096)
3268 blksize = 4096;
3269 else if (blksize > 1024 * 1024)
3270 blksize = 1024 * 1024;
3271 dat = malloc(blksize, M_TEMP, M_WAITOK);
3272
3273 /*
3274 * If VOP_IOCTL(FIOSEEKHOLE) works for invp, use it and FIOSEEKDATA
3275 * to find holes. Otherwise, just scan the read block for all 0s
3276 * in the inner loop where the data copying is done.
3277 * Note that some file systems such as NFSv3, NFSv4.0 and NFSv4.1 may
3278 * support holes on the server, but do not support FIOSEEKHOLE.
3279 * The kernel flag COPY_FILE_RANGE_TIMEO1SEC is used to indicate
3280 * that this function should return after 1second with a partial
3281 * completion.
3282 */
3283 if ((flags & COPY_FILE_RANGE_TIMEO1SEC) != 0) {
3284 getnanouptime(&endts);
3285 endts.tv_sec++;
3286 } else
3287 timespecclear(&endts);
3288 holetoeof = eof = false;
3289 while (len > 0 && error == 0 && !eof && interrupted == 0) {
3290 endoff = 0; /* To shut up compilers. */
3291 cantseek = true;
3292 startoff = *inoffp;
3293 copylen = len;
3294
3295 /*
3296 * Find the next data area. If there is just a hole to EOF,
3297 * FIOSEEKDATA should fail with ENXIO.
3298 * (I do not know if any file system will report a hole to
3299 * EOF via FIOSEEKHOLE, but I am pretty sure FIOSEEKDATA
3300 * will fail for those file systems.)
3301 *
3302 * For input files that don't support FIOSEEKDATA/FIOSEEKHOLE,
3303 * the code just falls through to the inner copy loop.
3304 */
3305 error = EINVAL;
3306 if (holein > 0) {
3307 error = VOP_IOCTL(invp, FIOSEEKDATA, &startoff, 0,
3308 incred, curthread);
3309 if (error == ENXIO) {
3310 startoff = endoff = inva.va_size;
3311 eof = holetoeof = true;
3312 error = 0;
3313 }
3314 }
3315 if (error == 0 && !holetoeof) {
3316 endoff = startoff;
3317 error = VOP_IOCTL(invp, FIOSEEKHOLE, &endoff, 0,
3318 incred, curthread);
3319 /*
3320 * Since invp is unlocked, it may be possible for
3321 * another thread to do a truncate(), lseek(), write()
3322 * creating a hole at startoff between the above
3323 * VOP_IOCTL() calls, if the other thread does not do
3324 * rangelocking.
3325 * If that happens, startoff == endoff and finding
3326 * the hole has failed, so set an error.
3327 */
3328 if (error == 0 && startoff == endoff)
3329 error = EINVAL; /* Any error. Reset to 0. */
3330 }
3331 if (error == 0) {
3332 if (startoff > *inoffp) {
3333 /* Found hole before data block. */
3334 xfer = MIN(startoff - *inoffp, len);
3335 if (*outoffp < va.va_size) {
3336 /* Must write 0s to punch hole. */
3337 xfer2 = MIN(va.va_size - *outoffp,
3338 xfer);
3339 memset(dat, 0, MIN(xfer2, blksize));
3340 error = vn_write_outvp(outvp, dat,
3341 *outoffp, xfer2, blksize, false,
3342 holeout > 0, outcred);
3343 }
3344
3345 if (error == 0 && *outoffp + xfer >
3346 va.va_size && (xfer == len || holetoeof)) {
3347 /* Grow output file (hole at end). */
3348 error = vn_write_outvp(outvp, dat,
3349 *outoffp, xfer, blksize, true,
3350 false, outcred);
3351 }
3352 if (error == 0) {
3353 *inoffp += xfer;
3354 *outoffp += xfer;
3355 len -= xfer;
3356 if (len < savlen) {
3357 interrupted = sig_intr();
3358 if (timespecisset(&endts) &&
3359 interrupted == 0) {
3360 getnanouptime(&curts);
3361 if (timespeccmp(&curts,
3362 &endts, >=))
3363 interrupted =
3364 EINTR;
3365 }
3366 }
3367 }
3368 }
3369 copylen = MIN(len, endoff - startoff);
3370 cantseek = false;
3371 } else {
3372 cantseek = true;
3373 startoff = *inoffp;
3374 copylen = len;
3375 error = 0;
3376 }
3377
3378 xfer = blksize;
3379 if (cantseek) {
3380 /*
3381 * Set first xfer to end at a block boundary, so that
3382 * holes are more likely detected in the loop below via
3383 * the for all bytes 0 method.
3384 */
3385 xfer -= (*inoffp % blksize);
3386 }
3387 /* Loop copying the data block. */
3388 while (copylen > 0 && error == 0 && !eof && interrupted == 0) {
3389 if (copylen < xfer)
3390 xfer = copylen;
3391 error = vn_lock(invp, LK_SHARED);
3392 if (error != 0)
3393 goto out;
3394 error = vn_rdwr(UIO_READ, invp, dat, xfer,
3395 startoff, UIO_SYSSPACE, IO_NODELOCKED,
3396 curthread->td_ucred, incred, &aresid,
3397 curthread);
3398 VOP_UNLOCK(invp);
3399 lastblock = false;
3400 if (error == 0 && aresid > 0) {
3401 /* Stop the copy at EOF on the input file. */
3402 xfer -= aresid;
3403 eof = true;
3404 lastblock = true;
3405 }
3406 if (error == 0) {
3407 /*
3408 * Skip the write for holes past the initial EOF
3409 * of the output file, unless this is the last
3410 * write of the output file at EOF.
3411 */
3412 readzeros = cantseek ? mem_iszero(dat, xfer) :
3413 false;
3414 if (xfer == len)
3415 lastblock = true;
3416 if (!cantseek || *outoffp < va.va_size ||
3417 lastblock || !readzeros)
3418 error = vn_write_outvp(outvp, dat,
3419 *outoffp, xfer, blksize,
3420 readzeros && lastblock &&
3421 *outoffp >= va.va_size, false,
3422 outcred);
3423 if (error == 0) {
3424 *inoffp += xfer;
3425 startoff += xfer;
3426 *outoffp += xfer;
3427 copylen -= xfer;
3428 len -= xfer;
3429 if (len < savlen) {
3430 interrupted = sig_intr();
3431 if (timespecisset(&endts) &&
3432 interrupted == 0) {
3433 getnanouptime(&curts);
3434 if (timespeccmp(&curts,
3435 &endts, >=))
3436 interrupted =
3437 EINTR;
3438 }
3439 }
3440 }
3441 }
3442 xfer = blksize;
3443 }
3444 }
3445out:
3446 *lenp = savlen - len;
3447 free(dat, M_TEMP);
3448 return (error);
3449}
3450
3451static int
3452vn_fallocate(struct file *fp, off_t offset, off_t len, struct thread *td)
3453{
3454 struct mount *mp;
3455 struct vnode *vp;
3456 off_t olen, ooffset;
3457 int error;
3458#ifdef AUDIT
3459 int audited_vnode1 = 0;
3460#endif
3461
3462 vp = fp->f_vnode;
3463 if (vp->v_type != VREG)
3464 return (ENODEV);
3465
3466 /* Allocating blocks may take a long time, so iterate. */
3467 for (;;) {
3468 olen = len;
3469 ooffset = offset;
3470
3471 bwillwrite();
3472 mp = NULL;
3473 error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
3474 if (error != 0)
3475 break;
3476 error = vn_lock(vp, LK_EXCLUSIVE);
3477 if (error != 0) {
3478 vn_finished_write(mp);
3479 break;
3480 }
3481#ifdef AUDIT
3482 if (!audited_vnode1) {
3483 AUDIT_ARG_VNODE1(vp);
3484 audited_vnode1 = 1;
3485 }
3486#endif
3487#ifdef MAC
3488 error = mac_vnode_check_write(td->td_ucred, fp->f_cred, vp);
3489 if (error == 0)
3490#endif
3491 error = VOP_ALLOCATE(vp, &offset, &len, 0,
3492 td->td_ucred);
3493 VOP_UNLOCK(vp);
3494 vn_finished_write(mp);
3495
3496 if (olen + ooffset != offset + len) {
3497 panic("offset + len changed from %jx/%jx to %jx/%jx",
3498 ooffset, olen, offset, len);
3499 }
3500 if (error != 0 || len == 0)
3501 break;
3502 KASSERT(olen > len, ("Iteration did not make progress?"));
3503 maybe_yield();
3504 }
3505
3506 return (error);
3507}
3508
3509static int
3510vn_deallocate_impl(struct vnode *vp, off_t *offset, off_t *length, int flags,
3511 int ioflag, struct ucred *cred, struct ucred *active_cred,
3512 struct ucred *file_cred)
3513{
3514 struct mount *mp;
3515 void *rl_cookie;
3516 off_t off, len;
3517 int error;
3518#ifdef AUDIT
3519 bool audited_vnode1 = false;
3520#endif
3521
3522 rl_cookie = NULL;
3523 error = 0;
3524 mp = NULL;
3525 off = *offset;
3526 len = *length;
3527
3528 if ((ioflag & (IO_NODELOCKED | IO_RANGELOCKED)) == 0)
3529 rl_cookie = vn_rangelock_wlock(vp, off, off + len);
3530 while (len > 0 && error == 0) {
3531 /*
3532 * Try to deallocate the longest range in one pass.
3533 * In case a pass takes too long to be executed, it returns
3534 * partial result. The residue will be proceeded in the next
3535 * pass.
3536 */
3537
3538 if ((ioflag & IO_NODELOCKED) == 0) {
3539 bwillwrite();
3540 if ((error = vn_start_write(vp, &mp,
3541 V_WAIT | PCATCH)) != 0)
3542 goto out;
3543 vn_lock(vp, vn_lktype_write(mp, vp) | LK_RETRY);
3544 }
3545#ifdef AUDIT
3546 if (!audited_vnode1) {
3547 AUDIT_ARG_VNODE1(vp);
3548 audited_vnode1 = true;
3549 }
3550#endif
3551
3552#ifdef MAC
3553 if ((ioflag & IO_NOMACCHECK) == 0)
3554 error = mac_vnode_check_write(active_cred, file_cred,
3555 vp);
3556#endif
3557 if (error == 0)
3558 error = VOP_DEALLOCATE(vp, &off, &len, flags, ioflag,
3559 cred);
3560
3561 if ((ioflag & IO_NODELOCKED) == 0) {
3562 VOP_UNLOCK(vp);
3563 if (mp != NULL) {
3564 vn_finished_write(mp);
3565 mp = NULL;
3566 }
3567 }
3568 if (error == 0 && len != 0)
3569 maybe_yield();
3570 }
3571out:
3572 if (rl_cookie != NULL)
3573 vn_rangelock_unlock(vp, rl_cookie);
3574 *offset = off;
3575 *length = len;
3576 return (error);
3577}
3578
3579/*
3580 * This function is supposed to be used in the situations where the deallocation
3581 * is not triggered by a user request.
3582 */
3583int
3584vn_deallocate(struct vnode *vp, off_t *offset, off_t *length, int flags,
3585 int ioflag, struct ucred *active_cred, struct ucred *file_cred)
3586{
3587 struct ucred *cred;
3588
3589 if (*offset < 0 || *length <= 0 || *length > OFF_MAX - *offset ||
3590 flags != 0)
3591 return (EINVAL);
3592 if (vp->v_type != VREG)
3593 return (ENODEV);
3594
3595 cred = file_cred != NOCRED ? file_cred : active_cred;
3596 return (vn_deallocate_impl(vp, offset, length, flags, ioflag, cred,
3597 active_cred, file_cred));
3598}
3599
3600static int
3601vn_fspacectl(struct file *fp, int cmd, off_t *offset, off_t *length, int flags,
3602 struct ucred *active_cred, struct thread *td)
3603{
3604 int error;
3605 struct vnode *vp;
3606 int ioflag;
3607
3608 vp = fp->f_vnode;
3609
3610 if (cmd != SPACECTL_DEALLOC || *offset < 0 || *length <= 0 ||
3611 *length > OFF_MAX - *offset || flags != 0)
3612 return (EINVAL);
3613 if (vp->v_type != VREG)
3614 return (ENODEV);
3615
3616 ioflag = get_write_ioflag(fp);
3617
3618 switch (cmd) {
3619 case SPACECTL_DEALLOC:
3620 error = vn_deallocate_impl(vp, offset, length, flags, ioflag,
3621 active_cred, active_cred, fp->f_cred);
3622 break;
3623 default:
3624 panic("vn_fspacectl: unknown cmd %d", cmd);
3625 }
3626
3627 return (error);
3628}
3629
3630static u_long vn_lock_pair_pause_cnt;
3631SYSCTL_ULONG(_debug, OID_AUTO, vn_lock_pair_pause, CTLFLAG_RD,
3632 &vn_lock_pair_pause_cnt, 0,
3633 "Count of vn_lock_pair deadlocks");
3634
3635u_int vn_lock_pair_pause_max;
3636SYSCTL_UINT(_debug, OID_AUTO, vn_lock_pair_pause_max, CTLFLAG_RW,
3637 &vn_lock_pair_pause_max, 0,
3638 "Max ticks for vn_lock_pair deadlock avoidance sleep");
3639
3640static void
3641vn_lock_pair_pause(const char *wmesg)
3642{
3643 atomic_add_long(&vn_lock_pair_pause_cnt, 1);
3644 pause(wmesg, prng32_bounded(vn_lock_pair_pause_max));
3645}
3646
3647/*
3648 * Lock pair of vnodes vp1, vp2, avoiding lock order reversal.
3649 * vp1_locked indicates whether vp1 is exclusively locked; if not, vp1
3650 * must be unlocked. Same for vp2 and vp2_locked. One of the vnodes
3651 * can be NULL.
3652 *
3653 * The function returns with both vnodes exclusively locked, and
3654 * guarantees that it does not create lock order reversal with other
3655 * threads during its execution. Both vnodes could be unlocked
3656 * temporary (and reclaimed).
3657 */
3658void
3659vn_lock_pair(struct vnode *vp1, bool vp1_locked, struct vnode *vp2,
3660 bool vp2_locked)
3661{
3662 int error;
3663
3664 if (vp1 == NULL && vp2 == NULL)
3665 return;
3666 if (vp1 != NULL) {
3667 if (vp1_locked)
3668 ASSERT_VOP_ELOCKED(vp1, "vp1");
3669 else
3670 ASSERT_VOP_UNLOCKED(vp1, "vp1");
3671 } else {
3672 vp1_locked = true;
3673 }
3674 if (vp2 != NULL) {
3675 if (vp2_locked)
3676 ASSERT_VOP_ELOCKED(vp2, "vp2");
3677 else
3678 ASSERT_VOP_UNLOCKED(vp2, "vp2");
3679 } else {
3680 vp2_locked = true;
3681 }
3682 if (!vp1_locked && !vp2_locked) {
3683 vn_lock(vp1, LK_EXCLUSIVE | LK_RETRY);
3684 vp1_locked = true;
3685 }
3686
3687 for (;;) {
3688 if (vp1_locked && vp2_locked)
3689 break;
3690 if (vp1_locked && vp2 != NULL) {
3691 if (vp1 != NULL) {
3692 error = VOP_LOCK1(vp2, LK_EXCLUSIVE | LK_NOWAIT,
3693 __FILE__, __LINE__);
3694 if (error == 0)
3695 break;
3696 VOP_UNLOCK(vp1);
3697 vp1_locked = false;
3698 vn_lock_pair_pause("vlp1");
3699 }
3700 vn_lock(vp2, LK_EXCLUSIVE | LK_RETRY);
3701 vp2_locked = true;
3702 }
3703 if (vp2_locked && vp1 != NULL) {
3704 if (vp2 != NULL) {
3705 error = VOP_LOCK1(vp1, LK_EXCLUSIVE | LK_NOWAIT,
3706 __FILE__, __LINE__);
3707 if (error == 0)
3708 break;
3709 VOP_UNLOCK(vp2);
3710 vp2_locked = false;
3711 vn_lock_pair_pause("vlp2");
3712 }
3713 vn_lock(vp1, LK_EXCLUSIVE | LK_RETRY);
3714 vp1_locked = true;
3715 }
3716 }
3717 if (vp1 != NULL)
3718 ASSERT_VOP_ELOCKED(vp1, "vp1 ret");
3719 if (vp2 != NULL)
3720 ASSERT_VOP_ELOCKED(vp2, "vp2 ret");
3721}
3722
3723int
3724vn_lktype_write(struct mount *mp, struct vnode *vp)
3725{
3726 if (MNT_SHARED_WRITES(mp) ||
3727 (mp == NULL && MNT_SHARED_WRITES(vp->v_mount)))
3728 return (LK_SHARED);
3729 return (LK_EXCLUSIVE);
3730}
type
device_property_type_t type
Definition: bus_if.m:941
vntype_to_kinfo
int vntype_to_kinfo(int vtype)
Definition: kern_descrip.c:4683
badfileops
struct fileops badfileops
Definition: kern_descrip.c:5036
knote
void knote(struct knlist *list, long hint, int lockflags)
Definition: kern_event.c:2363
malloc
void *() malloc(size_t size, struct malloc_type *mtp, int flags)
Definition: kern_malloc.c:632
free
void free(void *addr, struct malloc_type *mtp)
Definition: kern_malloc.c:907
mtxpool_sleep
struct mtx_pool __read_mostly * mtxpool_sleep
Definition: kern_mtxpool.c:84
mtx_pool_find
struct mtx * mtx_pool_find(struct mtx_pool *pool, void *ptr)
Definition: kern_mtxpool.c:101
priv_check
int priv_check(struct thread *td, int priv)
Definition: kern_priv.c:271
lim_cur
rlim_t() lim_cur(struct thread *td, int which)
Definition: kern_resource.c:1318
vn_sendfile
int vn_sendfile(struct file *fp, int sockfd, struct uio *hdr_uio, struct uio *trl_uio, off_t offset, size_t nbytes, off_t *sent, int flags, struct thread *td)
Definition: kern_sendfile.c:674
panic
void panic(const char *fmt,...)
Definition: kern_shutdown.c:884
sig_intr
int sig_intr(void)
Definition: kern_sig.c:3330
kern_psignal
void kern_psignal(struct proc *p, int sig)
Definition: kern_sig.c:2117
kern_yield
void kern_yield(int prio)
Definition: kern_synch.c:660
maybe_yield
void maybe_yield(void)
Definition: kern_synch.c:652
wakeup
void wakeup(const void *ident)
Definition: kern_synch.c:349
getnanouptime
void getnanouptime(struct timespec *tsp)
Definition: kern_tc.c:447
start
void *** start
Definition: linker_if.m:98
data
uint32_t * data
Definition: msi_if.m:90
addr
uint64_t * addr
Definition: msi_if.m:89
res
struct resource * res
Definition: pic_if.m:98
vn_io_fault_args
Definition: vfs_vnops.c:169
vn_io_fault_args::kind
enum vn_io_fault_args::@16 kind
vn_io_fault_args::doio
fo_rdwr_t * doio
Definition: vfs_vnops.c:179
vn_io_fault_args::fp
struct file * fp
Definition: vfs_vnops.c:178
vn_io_fault_args::args
union vn_io_fault_args::@17 args
vn_io_fault_args::vop_args
struct vn_io_fault_args::@17::vop_args_tag vop_args
vn_io_fault_args::fop_args
struct vn_io_fault_args::@17::fop_args_tag fop_args
vn_io_fault_args::VN_IO_FAULT_FOP
@ VN_IO_FAULT_FOP
Definition: vfs_vnops.c:171
vn_io_fault_args::VN_IO_FAULT_VOP
@ VN_IO_FAULT_VOP
Definition: vfs_vnops.c:172
vn_io_fault_args::flags
int flags
Definition: vfs_vnops.c:175
vn_io_fault_args::cred
struct ucred * cred
Definition: vfs_vnops.c:174
vn_io_fault_args::vp
struct vnode * vp
Definition: vfs_vnops.c:182
accmode
accmode_t accmode
Definition: subr_acl_nfs4.c:69
hz
int hz
Definition: subr_param.c:85
prng32_bounded
uint32_t prng32_bounded(uint32_t bound)
Definition: subr_prng.c:101
sleepq_release
void sleepq_release(const void *wchan)
Definition: subr_sleepqueue.c:294
sleepq_broadcast
int sleepq_broadcast(const void *wchan, int flags, int pri, int queue)
Definition: subr_sleepqueue.c:992
sleepq_add
void sleepq_add(const void *wchan, struct lock_object *lock, const char *wmesg, int flags, int queue)
Definition: subr_sleepqueue.c:309
sleepq_wait
void sleepq_wait(const void *wchan, int pri)
Definition: subr_sleepqueue.c:652
sleepq_lock
void sleepq_lock(const void *wchan)
Definition: subr_sleepqueue.c:262
flags
uint16_t flags
Definition: subr_stats.c:2
cloneuio
struct uio * cloneuio(struct uio *uiop)
Definition: subr_uio.c:401
uiomove
int uiomove(void *cp, int n, struct uio *uio)
Definition: subr_uio.c:195
mtx
struct mtx mtx
Definition: uipc_ktls.c:0
bremfree
void bremfree(struct buf *bp)
Definition: vfs_bio.c:1869
bufobj_wwait
int bufobj_wwait(struct bufobj *bo, int slpflag, int timeo)
Definition: vfs_bio.c:5171
bawrite
void bawrite(struct buf *bp)
Definition: vfs_bio.c:2580
bwillwrite
void bwillwrite(void)
Definition: vfs_bio.c:2631
vfs_bio_awrite
int vfs_bio_awrite(struct buf *bp)
Definition: vfs_bio.c:3229
vn_fullpath
int vn_fullpath(struct vnode *vp, char **retbuf, char **freebuf)
Definition: vfs_cache.c:3170
attrnamespace
int attrnamespace
Definition: vfs_extattr.c:716
NDFREE
void() NDFREE(struct nameidata *ndp, const u_int flags)
Definition: vfs_lookup.c:1555
namei
int namei(struct nameidata *ndp)
Definition: vfs_lookup.c:535
vfs_op_enter
void vfs_op_enter(struct mount *mp)
Definition: vfs_mount.c:1727
vfs_rel
void vfs_rel(struct mount *mp)
Definition: vfs_mount.c:645
vfs_op_exit_locked
void vfs_op_exit_locked(struct mount *mp)
Definition: vfs_mount.c:1759
vfs_op_exit
void vfs_op_exit(struct mount *mp)
Definition: vfs_mount.c:1771
vfs_ref
void vfs_ref(struct mount *mp)
Definition: vfs_mount.c:527
vref
void vref(struct vnode *vp)
Definition: vfs_subr.c:3065
vn_printf
void vn_printf(struct vnode *vp, const char *fmt,...)
Definition: vfs_subr.c:4134
vfs_unbusy
void vfs_unbusy(struct mount *mp)
Definition: vfs_subr.c:850
vrele
void vrele(struct vnode *vp)
Definition: vfs_subr.c:3334
vput
void vput(struct vnode *vp)
Definition: vfs_subr.c:3348
vfs_busy
int vfs_busy(struct mount *mp, int flags)
Definition: vfs_subr.c:786
vunref
void vunref(struct vnode *vp)
Definition: vfs_subr.c:3365
setfown
int setfown(struct thread *td, struct ucred *cred, struct vnode *vp, uid_t uid, gid_t gid)
Definition: vfs_syscalls.c:2984
setfmode
int setfmode(struct thread *td, struct ucred *cred, struct vnode *vp, int mode)
Definition: vfs_syscalls.c:2860
buf
struct stat * buf
Definition: vfs_syscalls.c:2423
mode
mode_t mode
Definition: vfs_syscalls.c:2910
vn_io_fault_prefault_user
static int vn_io_fault_prefault_user(const struct uio *uio)
Definition: vfs_vnops.c:1278
vn_deallocate_impl
static int vn_deallocate_impl(struct vnode *vp, off_t *offset, off_t *length, int flags, int ioflag, struct ucred *cred, struct ucred *active_cred, struct ucred *file_cred)
Definition: vfs_vnops.c:3510
vn_fill_kinfo
int vn_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
Definition: vfs_vnops.c:2631
vn_write_outvp
static int vn_write_outvp(struct vnode *outvp, char *dat, off_t outoff, off_t xfer, u_long blksize, bool growfile, bool checkhole, struct ucred *cred)
Definition: vfs_vnops.c:3100
foffset_unlock_uio
void foffset_unlock_uio(struct file *fp, struct uio *uio, int flags)
Definition: vfs_vnops.c:892
vn_lock_pair_pause
static void vn_lock_pair_pause(const char *wmesg)
Definition: vfs_vnops.c:3641
vn_vget_ino
int vn_vget_ino(struct vnode *vp, ino_t ino, int lkflags, struct vnode **rvp)
Definition: vfs_vnops.c:2316
vn_finished_secondary_write
void vn_finished_secondary_write(struct mount *mp)
Definition: vfs_vnops.c:2046
vn_copy_file_range
int vn_copy_file_range(struct vnode *invp, off_t *inoffp, struct vnode *outvp, off_t *outoffp, size_t *lenp, unsigned int flags, struct ucred *incred, struct ucred *outcred, struct thread *fsize_td)
Definition: vfs_vnops.c:2943
vn_poll
static fo_poll_t vn_poll
Definition: vfs_vnops.c:104
vn_extattr_get
int vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace, const char *attrname, int *buflen, char *buf, struct thread *td)
Definition: vfs_vnops.c:2199
_vn_lock_fallback
static int __noinline _vn_lock_fallback(struct vnode *vp, int flags, const char *file, int line, int error)
Definition: vfs_vnops.c:1767
vn_close1
static int vn_close1(struct vnode *vp, int flags, struct ucred *file_cred, struct thread *td, bool keep_ref)
Definition: vfs_vnops.c:523
get_write_ioflag
static int get_write_ioflag(struct file *fp)
Definition: vfs_vnops.c:920
get_advice
static int get_advice(struct file *fp, struct uio *uio)
Definition: vfs_vnops.c:900
vn_lock_pair_pause_max
u_int vn_lock_pair_pause_max
Definition: vfs_vnops.c:3635
vn_io_fault_enable
static int vn_io_fault_enable
Definition: vfs_vnops.c:132
vfs_write_suspend
int vfs_write_suspend(struct mount *mp, int flags)
Definition: vfs_vnops.c:2065
vn_io_fault_touch
static int vn_io_fault_touch(char *base, const struct uio *uio)
Definition: vfs_vnops.c:1267
vn_start_write
int vn_start_write(struct vnode *vp, struct mount **mpp, int flags)
Definition: vfs_vnops.c:1901
vn_lock_pair_pause_cnt
static u_long vn_lock_pair_pause_cnt
Definition: vfs_vnops.c:3630
vfs_allow_read_dir
static int vfs_allow_read_dir
Definition: vfs_vnops.c:146
vn_start_write_refed
static int vn_start_write_refed(struct mount *mp, int flags, bool mplocked)
Definition: vfs_vnops.c:1852
vn_io_fault1
static int vn_io_fault1(struct vnode *vp, struct uio *uio, struct vn_io_fault_args *args, struct thread *td)
Definition: vfs_vnops.c:1327
vn_rdwr
int vn_rdwr(enum uio_rw rw, struct vnode *vp, void *base, int len, off_t offset, enum uio_seg segflg, int ioflg, struct ucred *active_cred, struct ucred *file_cred, ssize_t *aresid, struct thread *td)
Definition: vfs_vnops.c:614
vn_vget_ino_gen
int vn_vget_ino_gen(struct vnode *vp, vn_get_ino_t alloc, void *alloc_arg, int lkflags, struct vnode **rvp)
Definition: vfs_vnops.c:2324
vn_bmap_seekhole_locked
int vn_bmap_seekhole_locked(struct vnode *vp, u_long cmd, off_t *off, struct ucred *cred)
Definition: vfs_vnops.c:2467
vn_chown
int vn_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred, struct thread *td)
Definition: vfs_vnops.c:2418
vnops
struct fileops vnops
Definition: vfs_vnops.c:111
vn_chmod
int vn_chmod(struct file *fp, mode_t mode, struct ucred *active_cred, struct thread *td)
Definition: vfs_vnops.c:2403
vn_io_faults_cnt
static u_long vn_io_faults_cnt
Definition: vfs_vnops.c:142
vn_rlimit_fsize
int vn_rlimit_fsize(const struct vnode *vp, const struct uio *uio, struct thread *td)
Definition: vfs_vnops.c:2367
vn_ioctl
static fo_ioctl_t vn_ioctl
Definition: vfs_vnops.c:103
vn_writechk
int vn_writechk(struct vnode *vp)
Definition: vfs_vnops.c:504
vn_generic_copy_file_range
int vn_generic_copy_file_range(struct vnode *invp, off_t *inoffp, struct vnode *outvp, off_t *outoffp, size_t *lenp, unsigned int flags, struct ucred *incred, struct ucred *outcred, struct thread *fsize_td)
Definition: vfs_vnops.c:3167
vn_start_secondary_write
int vn_start_secondary_write(struct vnode *vp, struct mount **mpp, int flags)
Definition: vfs_vnops.c:1946
vn_skip_hole
static off_t vn_skip_hole(struct vnode *outvp, off_t xfer2, off_t *outoffp, off_t *xferp, off_t *dataoffp, off_t *holeoffp, struct ucred *cred)
Definition: vfs_vnops.c:3025
open2nameif
static uint64_t open2nameif(int fmode, u_int vn_open_flags)
Definition: vfs_vnops.c:199
SYSCTL_INT
SYSCTL_INT(_debug, OID_AUTO, vn_io_fault_enable, CTLFLAG_RWTUN, &vn_io_fault_enable, 0, "Enable vn_io_fault lock avoidance")
vn_lktype_write
int vn_lktype_write(struct mount *mp, struct vnode *vp)
Definition: vfs_vnops.c:3724
vn_bmap_seekhole
int vn_bmap_seekhole(struct vnode *vp, u_long cmd, off_t *off, struct ucred *cred)
Definition: vfs_vnops.c:2520
vn_extattr_rm
int vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace, const char *attrname, struct thread *td)
Definition: vfs_vnops.c:2279
vn_pages_remove
void vn_pages_remove(struct vnode *vp, vm_pindex_t start, vm_pindex_t end)
Definition: vfs_vnops.c:2437
vn_rdwr_inchunks
int vn_rdwr_inchunks(enum uio_rw rw, struct vnode *vp, void *base, size_t len, off_t offset, enum uio_seg segflg, int ioflg, struct ucred *active_cred, struct ucred *file_cred, size_t *aresid, struct thread *td)
Definition: vfs_vnops.c:718
vn_deallocate
int vn_deallocate(struct vnode *vp, off_t *offset, off_t *length, int flags, int ioflag, struct ucred *active_cred, struct ucred *file_cred)
Definition: vfs_vnops.c:3584
foffset_lock_uio
void foffset_lock_uio(struct file *fp, struct uio *uio, int flags)
Definition: vfs_vnops.c:884
__FBSDID
__FBSDID("$FreeBSD$")
vn_utimes_perm
int vn_utimes_perm(struct vnode *vp, struct vattr *vap, struct ucred *cred, struct thread *td)
Definition: vfs_vnops.c:2608
vn_statfile
int vn_statfile(struct file *fp, struct stat *sb, struct ucred *active_cred)
Definition: vfs_vnops.c:1673
vn_io_fault_doio
static int vn_io_fault_doio(struct vn_io_fault_args *args, struct uio *uio, struct thread *td)
Definition: vfs_vnops.c:1237
_vn_lock
int _vn_lock(struct vnode *vp, int flags, const char *file, int line)
Definition: vfs_vnops.c:1804
vn_io_pgcache_read_enable
static int vn_io_pgcache_read_enable
Definition: vfs_vnops.c:138
vn_fallocate
static fo_fallocate_t vn_fallocate
Definition: vfs_vnops.c:108
vn_read
static fo_rdwr_t vn_read
Definition: vfs_vnops.c:99
SYSCTL_ULONG
SYSCTL_ULONG(_debug, OID_AUTO, vn_io_faults, CTLFLAG_RD, &vn_io_faults_cnt, 0, "Count of vn_io_fault lock avoidance triggers")
vn_fill_kinfo_vnode
int vn_fill_kinfo_vnode(struct vnode *vp, struct kinfo_file *kif)
Definition: vfs_vnops.c:2668
do_vn_io_fault
static bool do_vn_io_fault(struct vnode *vp, struct uio *uio)
Definition: vfs_vnops.c:156
mem_iszero
static bool mem_iszero(void *dat, int len)
Definition: vfs_vnops.c:2998
vn_io_fault_uiomove
int vn_io_fault_uiomove(char *data, int xfersize, struct uio *uio)
Definition: vfs_vnops.c:1508
vn_seek
int vn_seek(struct file *fp, off_t offset, int whence, struct thread *td)
Definition: vfs_vnops.c:2535
foffset_unlock
void foffset_unlock(struct file *fp, off_t val, int flags)
Definition: vfs_vnops.c:803
vn_open
int vn_open(struct nameidata *ndp, int *flagp, int cmode, struct file *fp)
Definition: vfs_vnops.c:191
vn_kqfilter_opath
int vn_kqfilter_opath(struct file *fp, struct knote *kn)
Definition: vfs_vnops.c:2186
vn_open_cred
int vn_open_cred(struct nameidata *ndp, int *flagp, int cmode, u_int vn_open_flags, struct ucred *cred, struct file *fp)
Definition: vfs_vnops.c:228
vn_io_fault_pgmove
int vn_io_fault_pgmove(vm_page_t ma[], vm_offset_t offset, int xfersize, struct uio *uio)
Definition: vfs_vnops.c:1564
vn_fsync_buf
int vn_fsync_buf(struct vnode *vp, int waitfor)
Definition: vfs_vnops.c:2840
vn_get_ino_alloc_vget
static int vn_get_ino_alloc_vget(struct mount *mp, void *arg, int lkflags, struct vnode **rvp)
Definition: vfs_vnops.c:2308
vn_write
static fo_rdwr_t vn_write
Definition: vfs_vnops.c:100
vn_pages_remove_valid
void vn_pages_remove_valid(struct vnode *vp, vm_pindex_t start, vm_pindex_t end)
Definition: vfs_vnops.c:2455
vn_fsid
void vn_fsid(struct vnode *vp, struct vattr *va)
Definition: vfs_vnops.c:2829
vfs_write_suspend_umnt
int vfs_write_suspend_umnt(struct mount *mp)
Definition: vfs_vnops.c:2147
vn_truncate
static fo_truncate_t vn_truncate
Definition: vfs_vnops.c:102
vn_close
int vn_close(struct vnode *vp, int flags, struct ucred *file_cred, struct thread *td)
Definition: vfs_vnops.c:553
vn_fspacectl
static fo_fspacectl_t vn_fspacectl
Definition: vfs_vnops.c:109
vn_kqfilter
static fo_kqfilter_t vn_kqfilter
Definition: vfs_vnops.c:105
vn_io_fault
static fo_rdwr_t vn_io_fault
Definition: vfs_vnops.c:101
vn_lock_pair
void vn_lock_pair(struct vnode *vp1, bool vp1_locked, struct vnode *vp2, bool vp2_locked)
Definition: vfs_vnops.c:3659
vn_open_vnode_advlock
static int vn_open_vnode_advlock(struct vnode *vp, int fmode, struct file *fp)
Definition: vfs_vnops.c:354
vn_fill_junk
static void vn_fill_junk(struct kinfo_file *kif)
Definition: vfs_vnops.c:2650
vn_mmap
static fo_mmap_t vn_mmap
Definition: vfs_vnops.c:107
sequential_heuristic
static int sequential_heuristic(struct uio *uio, struct file *fp)
Definition: vfs_vnops.c:564
vn_finished_write
void vn_finished_write(struct mount *mp)
Definition: vfs_vnops.c:2009
SYSCTL_UINT
SYSCTL_UINT(_debug, OID_AUTO, vn_lock_pair_pause_max, CTLFLAG_RW, &vn_lock_pair_pause_max, 0, "Max ticks for vn_lock_pair deadlock avoidance sleep")
vfs_write_resume
void vfs_write_resume(struct mount *mp, int flags)
Definition: vfs_vnops.c:2114
vn_read_from_obj
int vn_read_from_obj(struct vnode *vp, struct uio *uio)
Definition: vfs_vnops.c:949
vn_extattr_set
int vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace, const char *attrname, int buflen, char *buf, struct thread *td)
Definition: vfs_vnops.c:2240
vn_closefile
static fo_close_t vn_closefile
Definition: vfs_vnops.c:106
vn_io_fault_prefault
static int vn_io_fault_prefault
Definition: vfs_vnops.c:135
vn_open_vnode
int vn_open_vnode(struct vnode *vp, int fmode, struct ucred *cred, struct thread *td, struct file *fp)
Definition: vfs_vnops.c:391
foffset_lock
off_t foffset_lock(struct file *fp, int flags)
Definition: vfs_vnops.c:757
vn_truncate_locked
int vn_truncate_locked(struct vnode *vp, off_t length, bool sync, struct ucred *cred)
Definition: vfs_vnops.c:1651
io_hold_cnt
const u_int io_hold_cnt
Definition: vfs_vnops.c:131