2 * SPDX-License-Identifier: BSD-3-Clause
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.
12 * Copyright (c) 2012 Konstantin Belousov <kib@FreeBSD.org>
13 * Copyright (c) 2013, 2014 The FreeBSD Foundation
15 * Portions of this software were developed by Konstantin Belousov
16 * under sponsorship from the FreeBSD Foundation.
18 * Redistribution and use in source and binary forms, with or without
19 * modification, are permitted provided that the following conditions
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.
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
42 * @(#)vfs_vnops.c 8.2 (Berkeley) 1/21/94
45 #include <sys/cdefs.h>
46 __FBSDID("$FreeBSD$");
48 #include "opt_hwpmc_hooks.h"
50 #include <sys/param.h>
51 #include <sys/systm.h>
54 #include <sys/fcntl.h>
61 #include <sys/limits.h>
64 #include <sys/mount.h>
65 #include <sys/mutex.h>
66 #include <sys/namei.h>
67 #include <sys/vnode.h>
70 #include <sys/filio.h>
71 #include <sys/resourcevar.h>
72 #include <sys/rwlock.h>
74 #include <sys/sleepqueue.h>
75 #include <sys/sysctl.h>
76 #include <sys/ttycom.h>
78 #include <sys/syslog.h>
79 #include <sys/unistd.h>
82 #include <security/audit/audit.h>
83 #include <security/mac/mac_framework.h>
86 #include <vm/vm_extern.h>
88 #include <vm/vm_map.h>
89 #include <vm/vm_object.h>
90 #include <vm/vm_page.h>
91 #include <vm/vm_pager.h>
94 #include <sys/pmckern.h>
97 static fo_rdwr_t vn_read;
98 static fo_rdwr_t vn_write;
99 static fo_rdwr_t vn_io_fault;
100 static fo_truncate_t vn_truncate;
101 static fo_ioctl_t vn_ioctl;
102 static fo_poll_t vn_poll;
103 static fo_kqfilter_t vn_kqfilter;
104 static fo_stat_t vn_statfile;
105 static fo_close_t vn_closefile;
106 static fo_mmap_t vn_mmap;
107 static fo_fallocate_t vn_fallocate;
109 struct fileops vnops = {
110 .fo_read = vn_io_fault,
111 .fo_write = vn_io_fault,
112 .fo_truncate = vn_truncate,
113 .fo_ioctl = vn_ioctl,
115 .fo_kqfilter = vn_kqfilter,
116 .fo_stat = vn_statfile,
117 .fo_close = vn_closefile,
118 .fo_chmod = vn_chmod,
119 .fo_chown = vn_chown,
120 .fo_sendfile = vn_sendfile,
122 .fo_fill_kinfo = vn_fill_kinfo,
124 .fo_fallocate = vn_fallocate,
125 .fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE
128 static const int io_hold_cnt = 16;
129 static int vn_io_fault_enable = 1;
130 SYSCTL_INT(_debug, OID_AUTO, vn_io_fault_enable, CTLFLAG_RWTUN,
131 &vn_io_fault_enable, 0, "Enable vn_io_fault lock avoidance");
132 static int vn_io_fault_prefault = 0;
133 SYSCTL_INT(_debug, OID_AUTO, vn_io_fault_prefault, CTLFLAG_RWTUN,
134 &vn_io_fault_prefault, 0, "Enable vn_io_fault prefaulting");
135 static int vn_io_pgcache_read_enable = 1;
136 SYSCTL_INT(_debug, OID_AUTO, vn_io_pgcache_read_enable, CTLFLAG_RWTUN,
137 &vn_io_pgcache_read_enable, 0,
138 "Enable copying from page cache for reads, avoiding fs");
139 static u_long vn_io_faults_cnt;
140 SYSCTL_ULONG(_debug, OID_AUTO, vn_io_faults, CTLFLAG_RD,
141 &vn_io_faults_cnt, 0, "Count of vn_io_fault lock avoidance triggers");
143 static int vfs_allow_read_dir = 0;
144 SYSCTL_INT(_security_bsd, OID_AUTO, allow_read_dir, CTLFLAG_RW,
145 &vfs_allow_read_dir, 0,
146 "Enable read(2) of directory by root for filesystems that support it");
149 * Returns true if vn_io_fault mode of handling the i/o request should
153 do_vn_io_fault(struct vnode *vp, struct uio *uio)
157 return (uio->uio_segflg == UIO_USERSPACE && vp->v_type == VREG &&
158 (mp = vp->v_mount) != NULL &&
159 (mp->mnt_kern_flag & MNTK_NO_IOPF) != 0 && vn_io_fault_enable);
163 * Structure used to pass arguments to vn_io_fault1(), to do either
164 * file- or vnode-based I/O calls.
166 struct vn_io_fault_args {
174 struct fop_args_tag {
178 struct vop_args_tag {
184 static int vn_io_fault1(struct vnode *vp, struct uio *uio,
185 struct vn_io_fault_args *args, struct thread *td);
188 vn_open(struct nameidata *ndp, int *flagp, int cmode, struct file *fp)
190 struct thread *td = ndp->ni_cnd.cn_thread;
192 return (vn_open_cred(ndp, flagp, cmode, 0, td->td_ucred, fp));
196 * Common code for vnode open operations via a name lookup.
197 * Lookup the vnode and invoke VOP_CREATE if needed.
198 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine.
200 * Note that this does NOT free nameidata for the successful case,
201 * due to the NDINIT being done elsewhere.
204 vn_open_cred(struct nameidata *ndp, int *flagp, int cmode, u_int vn_open_flags,
205 struct ucred *cred, struct file *fp)
209 struct thread *td = ndp->ni_cnd.cn_thread;
211 struct vattr *vap = &vat;
216 if ((fmode & (O_CREAT | O_EXCL | O_DIRECTORY)) == (O_CREAT |
217 O_EXCL | O_DIRECTORY))
219 else if ((fmode & (O_CREAT | O_DIRECTORY)) == O_CREAT) {
220 ndp->ni_cnd.cn_nameiop = CREATE;
222 * Set NOCACHE to avoid flushing the cache when
223 * rolling in many files at once.
225 ndp->ni_cnd.cn_flags = ISOPEN | LOCKPARENT | LOCKLEAF | NOCACHE;
226 if ((fmode & O_EXCL) == 0 && (fmode & O_NOFOLLOW) == 0)
227 ndp->ni_cnd.cn_flags |= FOLLOW;
228 if ((fmode & O_BENEATH) != 0)
229 ndp->ni_cnd.cn_flags |= BENEATH;
230 if (!(vn_open_flags & VN_OPEN_NOAUDIT))
231 ndp->ni_cnd.cn_flags |= AUDITVNODE1;
232 if (vn_open_flags & VN_OPEN_NOCAPCHECK)
233 ndp->ni_cnd.cn_flags |= NOCAPCHECK;
234 if ((vn_open_flags & VN_OPEN_INVFS) == 0)
236 if ((error = namei(ndp)) != 0)
238 if (ndp->ni_vp == NULL) {
241 vap->va_mode = cmode;
243 vap->va_vaflags |= VA_EXCLUSIVE;
244 if (vn_start_write(ndp->ni_dvp, &mp, V_NOWAIT) != 0) {
245 NDFREE(ndp, NDF_ONLY_PNBUF);
247 if ((error = vn_start_write(NULL, &mp,
248 V_XSLEEP | PCATCH)) != 0)
252 if ((vn_open_flags & VN_OPEN_NAMECACHE) != 0)
253 ndp->ni_cnd.cn_flags |= MAKEENTRY;
255 error = mac_vnode_check_create(cred, ndp->ni_dvp,
259 error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp,
262 vn_finished_write(mp);
264 NDFREE(ndp, NDF_ONLY_PNBUF);
270 if (ndp->ni_dvp == ndp->ni_vp)
276 if (fmode & O_EXCL) {
280 if (vp->v_type == VDIR) {
287 ndp->ni_cnd.cn_nameiop = LOOKUP;
288 ndp->ni_cnd.cn_flags = ISOPEN |
289 ((fmode & O_NOFOLLOW) ? NOFOLLOW : FOLLOW) | LOCKLEAF;
290 if (!(fmode & FWRITE))
291 ndp->ni_cnd.cn_flags |= LOCKSHARED;
292 if ((fmode & O_BENEATH) != 0)
293 ndp->ni_cnd.cn_flags |= BENEATH;
294 if (!(vn_open_flags & VN_OPEN_NOAUDIT))
295 ndp->ni_cnd.cn_flags |= AUDITVNODE1;
296 if (vn_open_flags & VN_OPEN_NOCAPCHECK)
297 ndp->ni_cnd.cn_flags |= NOCAPCHECK;
298 if ((error = namei(ndp)) != 0)
302 error = vn_open_vnode(vp, fmode, cred, td, fp);
308 NDFREE(ndp, NDF_ONLY_PNBUF);
316 vn_open_vnode_advlock(struct vnode *vp, int fmode, struct file *fp)
319 int error, lock_flags, type;
321 ASSERT_VOP_LOCKED(vp, "vn_open_vnode_advlock");
322 if ((fmode & (O_EXLOCK | O_SHLOCK)) == 0)
324 KASSERT(fp != NULL, ("open with flock requires fp"));
325 if (fp->f_type != DTYPE_NONE && fp->f_type != DTYPE_VNODE)
328 lock_flags = VOP_ISLOCKED(vp);
331 lf.l_whence = SEEK_SET;
334 lf.l_type = (fmode & O_EXLOCK) != 0 ? F_WRLCK : F_RDLCK;
336 if ((fmode & FNONBLOCK) == 0)
338 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, type);
340 fp->f_flag |= FHASLOCK;
342 vn_lock(vp, lock_flags | LK_RETRY);
343 if (error == 0 && VN_IS_DOOMED(vp))
349 * Common code for vnode open operations once a vnode is located.
350 * Check permissions, and call the VOP_OPEN routine.
353 vn_open_vnode(struct vnode *vp, int fmode, struct ucred *cred,
354 struct thread *td, struct file *fp)
359 if (vp->v_type == VLNK)
361 if (vp->v_type == VSOCK)
363 if (vp->v_type != VDIR && fmode & O_DIRECTORY)
366 if (fmode & (FWRITE | O_TRUNC)) {
367 if (vp->v_type == VDIR)
375 if ((fmode & O_APPEND) && (fmode & FWRITE))
380 if (fmode & O_VERIFY)
382 error = mac_vnode_check_open(cred, vp, accmode);
386 accmode &= ~(VCREAT | VVERIFY);
388 if ((fmode & O_CREAT) == 0 && accmode != 0) {
389 error = VOP_ACCESS(vp, accmode, cred, td);
393 if (vp->v_type == VFIFO && VOP_ISLOCKED(vp) != LK_EXCLUSIVE)
394 vn_lock(vp, LK_UPGRADE | LK_RETRY);
395 error = VOP_OPEN(vp, fmode, cred, td, fp);
399 error = vn_open_vnode_advlock(vp, fmode, fp);
400 if (error == 0 && (fmode & FWRITE) != 0) {
401 error = VOP_ADD_WRITECOUNT(vp, 1);
403 CTR3(KTR_VFS, "%s: vp %p v_writecount increased to %d",
404 __func__, vp, vp->v_writecount);
409 * Error from advlock or VOP_ADD_WRITECOUNT() still requires
410 * calling VOP_CLOSE() to pair with earlier VOP_OPEN().
411 * Arrange for that by having fdrop() to use vn_closefile().
414 fp->f_flag |= FOPENFAILED;
416 if (fp->f_ops == &badfileops) {
417 fp->f_type = DTYPE_VNODE;
423 ASSERT_VOP_LOCKED(vp, "vn_open_vnode");
429 * Check for write permissions on the specified vnode.
430 * Prototype text segments cannot be written.
434 vn_writechk(struct vnode *vp)
437 ASSERT_VOP_LOCKED(vp, "vn_writechk");
439 * If there's shared text associated with
440 * the vnode, try to free it up once. If
441 * we fail, we can't allow writing.
453 vn_close1(struct vnode *vp, int flags, struct ucred *file_cred,
454 struct thread *td, bool keep_ref)
457 int error, lock_flags;
459 if (vp->v_type != VFIFO && (flags & FWRITE) == 0 &&
460 MNT_EXTENDED_SHARED(vp->v_mount))
461 lock_flags = LK_SHARED;
463 lock_flags = LK_EXCLUSIVE;
465 vn_start_write(vp, &mp, V_WAIT);
466 vn_lock(vp, lock_flags | LK_RETRY);
467 AUDIT_ARG_VNODE1(vp);
468 if ((flags & (FWRITE | FOPENFAILED)) == FWRITE) {
469 VOP_ADD_WRITECOUNT_CHECKED(vp, -1);
470 CTR3(KTR_VFS, "%s: vp %p v_writecount decreased to %d",
471 __func__, vp, vp->v_writecount);
473 error = VOP_CLOSE(vp, flags, file_cred, td);
478 vn_finished_write(mp);
483 vn_close(struct vnode *vp, int flags, struct ucred *file_cred,
487 return (vn_close1(vp, flags, file_cred, td, false));
491 * Heuristic to detect sequential operation.
494 sequential_heuristic(struct uio *uio, struct file *fp)
498 ASSERT_VOP_LOCKED(fp->f_vnode, __func__);
501 if (fp->f_flag & FRDAHEAD)
502 return (fp->f_seqcount[rw] << IO_SEQSHIFT);
505 * Offset 0 is handled specially. open() sets f_seqcount to 1 so
506 * that the first I/O is normally considered to be slightly
507 * sequential. Seeking to offset 0 doesn't change sequentiality
508 * unless previous seeks have reduced f_seqcount to 0, in which
509 * case offset 0 is not special.
511 if ((uio->uio_offset == 0 && fp->f_seqcount[rw] > 0) ||
512 uio->uio_offset == fp->f_nextoff[rw]) {
514 * f_seqcount is in units of fixed-size blocks so that it
515 * depends mainly on the amount of sequential I/O and not
516 * much on the number of sequential I/O's. The fixed size
517 * of 16384 is hard-coded here since it is (not quite) just
518 * a magic size that works well here. This size is more
519 * closely related to the best I/O size for real disks than
520 * to any block size used by software.
522 if (uio->uio_resid >= IO_SEQMAX * 16384)
523 fp->f_seqcount[rw] = IO_SEQMAX;
525 fp->f_seqcount[rw] += howmany(uio->uio_resid, 16384);
526 if (fp->f_seqcount[rw] > IO_SEQMAX)
527 fp->f_seqcount[rw] = IO_SEQMAX;
529 return (fp->f_seqcount[rw] << IO_SEQSHIFT);
532 /* Not sequential. Quickly draw-down sequentiality. */
533 if (fp->f_seqcount[rw] > 1)
534 fp->f_seqcount[rw] = 1;
536 fp->f_seqcount[rw] = 0;
541 * Package up an I/O request on a vnode into a uio and do it.
544 vn_rdwr(enum uio_rw rw, struct vnode *vp, void *base, int len, off_t offset,
545 enum uio_seg segflg, int ioflg, struct ucred *active_cred,
546 struct ucred *file_cred, ssize_t *aresid, struct thread *td)
553 struct vn_io_fault_args args;
554 int error, lock_flags;
556 if (offset < 0 && vp->v_type != VCHR)
558 auio.uio_iov = &aiov;
560 aiov.iov_base = base;
562 auio.uio_resid = len;
563 auio.uio_offset = offset;
564 auio.uio_segflg = segflg;
569 if ((ioflg & IO_NODELOCKED) == 0) {
570 if ((ioflg & IO_RANGELOCKED) == 0) {
571 if (rw == UIO_READ) {
572 rl_cookie = vn_rangelock_rlock(vp, offset,
575 rl_cookie = vn_rangelock_wlock(vp, offset,
581 if (rw == UIO_WRITE) {
582 if (vp->v_type != VCHR &&
583 (error = vn_start_write(vp, &mp, V_WAIT | PCATCH))
586 if (MNT_SHARED_WRITES(mp) ||
587 ((mp == NULL) && MNT_SHARED_WRITES(vp->v_mount)))
588 lock_flags = LK_SHARED;
590 lock_flags = LK_EXCLUSIVE;
592 lock_flags = LK_SHARED;
593 vn_lock(vp, lock_flags | LK_RETRY);
597 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
599 if ((ioflg & IO_NOMACCHECK) == 0) {
601 error = mac_vnode_check_read(active_cred, file_cred,
604 error = mac_vnode_check_write(active_cred, file_cred,
609 if (file_cred != NULL)
613 if (do_vn_io_fault(vp, &auio)) {
614 args.kind = VN_IO_FAULT_VOP;
617 args.args.vop_args.vp = vp;
618 error = vn_io_fault1(vp, &auio, &args, td);
619 } else if (rw == UIO_READ) {
620 error = VOP_READ(vp, &auio, ioflg, cred);
621 } else /* if (rw == UIO_WRITE) */ {
622 error = VOP_WRITE(vp, &auio, ioflg, cred);
626 *aresid = auio.uio_resid;
628 if (auio.uio_resid && error == 0)
630 if ((ioflg & IO_NODELOCKED) == 0) {
633 vn_finished_write(mp);
636 if (rl_cookie != NULL)
637 vn_rangelock_unlock(vp, rl_cookie);
642 * Package up an I/O request on a vnode into a uio and do it. The I/O
643 * request is split up into smaller chunks and we try to avoid saturating
644 * the buffer cache while potentially holding a vnode locked, so we
645 * check bwillwrite() before calling vn_rdwr(). We also call kern_yield()
646 * to give other processes a chance to lock the vnode (either other processes
647 * core'ing the same binary, or unrelated processes scanning the directory).
650 vn_rdwr_inchunks(enum uio_rw rw, struct vnode *vp, void *base, size_t len,
651 off_t offset, enum uio_seg segflg, int ioflg, struct ucred *active_cred,
652 struct ucred *file_cred, size_t *aresid, struct thread *td)
661 * Force `offset' to a multiple of MAXBSIZE except possibly
662 * for the first chunk, so that filesystems only need to
663 * write full blocks except possibly for the first and last
666 chunk = MAXBSIZE - (uoff_t)offset % MAXBSIZE;
670 if (rw != UIO_READ && vp->v_type == VREG)
673 error = vn_rdwr(rw, vp, base, chunk, offset, segflg,
674 ioflg, active_cred, file_cred, &iaresid, td);
675 len -= chunk; /* aresid calc already includes length */
679 base = (char *)base + chunk;
680 kern_yield(PRI_USER);
683 *aresid = len + iaresid;
687 #if OFF_MAX <= LONG_MAX
689 foffset_lock(struct file *fp, int flags)
691 volatile short *flagsp;
695 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
697 if ((flags & FOF_NOLOCK) != 0)
698 return (atomic_load_long(&fp->f_offset));
701 * According to McKusick the vn lock was protecting f_offset here.
702 * It is now protected by the FOFFSET_LOCKED flag.
704 flagsp = &fp->f_vnread_flags;
705 if (atomic_cmpset_acq_16(flagsp, 0, FOFFSET_LOCKED))
706 return (atomic_load_long(&fp->f_offset));
708 sleepq_lock(&fp->f_vnread_flags);
709 state = atomic_load_16(flagsp);
711 if ((state & FOFFSET_LOCKED) == 0) {
712 if (!atomic_fcmpset_acq_16(flagsp, &state,
717 if ((state & FOFFSET_LOCK_WAITING) == 0) {
718 if (!atomic_fcmpset_acq_16(flagsp, &state,
719 state | FOFFSET_LOCK_WAITING))
723 sleepq_add(&fp->f_vnread_flags, NULL, "vofflock", 0, 0);
724 sleepq_wait(&fp->f_vnread_flags, PUSER -1);
726 sleepq_lock(&fp->f_vnread_flags);
727 state = atomic_load_16(flagsp);
729 res = atomic_load_long(&fp->f_offset);
730 sleepq_release(&fp->f_vnread_flags);
735 foffset_unlock(struct file *fp, off_t val, int flags)
737 volatile short *flagsp;
740 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
742 if ((flags & FOF_NOUPDATE) == 0)
743 atomic_store_long(&fp->f_offset, val);
744 if ((flags & FOF_NEXTOFF_R) != 0)
745 fp->f_nextoff[UIO_READ] = val;
746 if ((flags & FOF_NEXTOFF_W) != 0)
747 fp->f_nextoff[UIO_WRITE] = val;
749 if ((flags & FOF_NOLOCK) != 0)
752 flagsp = &fp->f_vnread_flags;
753 state = atomic_load_16(flagsp);
754 if ((state & FOFFSET_LOCK_WAITING) == 0 &&
755 atomic_cmpset_rel_16(flagsp, state, 0))
758 sleepq_lock(&fp->f_vnread_flags);
759 MPASS((fp->f_vnread_flags & FOFFSET_LOCKED) != 0);
760 MPASS((fp->f_vnread_flags & FOFFSET_LOCK_WAITING) != 0);
761 fp->f_vnread_flags = 0;
762 sleepq_broadcast(&fp->f_vnread_flags, SLEEPQ_SLEEP, 0, 0);
763 sleepq_release(&fp->f_vnread_flags);
767 foffset_lock(struct file *fp, int flags)
772 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
774 mtxp = mtx_pool_find(mtxpool_sleep, fp);
776 if ((flags & FOF_NOLOCK) == 0) {
777 while (fp->f_vnread_flags & FOFFSET_LOCKED) {
778 fp->f_vnread_flags |= FOFFSET_LOCK_WAITING;
779 msleep(&fp->f_vnread_flags, mtxp, PUSER -1,
782 fp->f_vnread_flags |= FOFFSET_LOCKED;
790 foffset_unlock(struct file *fp, off_t val, int flags)
794 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
796 mtxp = mtx_pool_find(mtxpool_sleep, fp);
798 if ((flags & FOF_NOUPDATE) == 0)
800 if ((flags & FOF_NEXTOFF_R) != 0)
801 fp->f_nextoff[UIO_READ] = val;
802 if ((flags & FOF_NEXTOFF_W) != 0)
803 fp->f_nextoff[UIO_WRITE] = val;
804 if ((flags & FOF_NOLOCK) == 0) {
805 KASSERT((fp->f_vnread_flags & FOFFSET_LOCKED) != 0,
806 ("Lost FOFFSET_LOCKED"));
807 if (fp->f_vnread_flags & FOFFSET_LOCK_WAITING)
808 wakeup(&fp->f_vnread_flags);
809 fp->f_vnread_flags = 0;
816 foffset_lock_uio(struct file *fp, struct uio *uio, int flags)
819 if ((flags & FOF_OFFSET) == 0)
820 uio->uio_offset = foffset_lock(fp, flags);
824 foffset_unlock_uio(struct file *fp, struct uio *uio, int flags)
827 if ((flags & FOF_OFFSET) == 0)
828 foffset_unlock(fp, uio->uio_offset, flags);
832 get_advice(struct file *fp, struct uio *uio)
837 ret = POSIX_FADV_NORMAL;
838 if (fp->f_advice == NULL || fp->f_vnode->v_type != VREG)
841 mtxp = mtx_pool_find(mtxpool_sleep, fp);
843 if (fp->f_advice != NULL &&
844 uio->uio_offset >= fp->f_advice->fa_start &&
845 uio->uio_offset + uio->uio_resid <= fp->f_advice->fa_end)
846 ret = fp->f_advice->fa_advice;
852 vn_read_from_obj(struct vnode *vp, struct uio *uio)
855 vm_page_t ma[io_hold_cnt + 2];
861 MPASS(uio->uio_resid <= ptoa(io_hold_cnt + 2));
863 MPASS(obj->type == OBJT_VNODE);
866 * Depends on type stability of vm_objects.
868 vm_object_pip_add(obj, 1);
869 if ((obj->flags & OBJ_DEAD) != 0) {
871 * Note that object might be already reused from the
872 * vnode, and the OBJ_DEAD flag cleared. This is fine,
873 * we recheck for DOOMED vnode state after all pages
874 * are busied, and retract then.
876 * But we check for OBJ_DEAD to ensure that we do not
877 * busy pages while vm_object_terminate_pages()
878 * processes the queue.
884 resid = uio->uio_resid;
885 off = uio->uio_offset;
886 for (i = 0; resid > 0; i++) {
887 MPASS(i < io_hold_cnt + 2);
888 ma[i] = vm_page_grab_unlocked(obj, atop(off),
889 VM_ALLOC_NOCREAT | VM_ALLOC_SBUSY | VM_ALLOC_IGN_SBUSY |
895 * Skip invalid pages. Valid mask can be partial only
896 * at EOF, and we clip later.
898 if (vm_page_none_valid(ma[i])) {
899 vm_page_sunbusy(ma[i]);
912 * Check VIRF_DOOMED after we busied our pages. Since
913 * vgonel() terminates the vnode' vm_object, it cannot
914 * process past pages busied by us.
916 if (VN_IS_DOOMED(vp)) {
921 resid = PAGE_SIZE - (uio->uio_offset & PAGE_MASK) + ptoa(i - 1);
922 if (resid > uio->uio_resid)
923 resid = uio->uio_resid;
926 * Unlocked read of vnp_size is safe because truncation cannot
927 * pass busied page. But we load vnp_size into a local
928 * variable so that possible concurrent extension does not
931 #if defined(__powerpc__) && !defined(__powerpc64__)
932 vsz = obj->un_pager.vnp.vnp_size;
934 vsz = atomic_load_64(&obj->un_pager.vnp.vnp_size);
936 if (uio->uio_offset + resid > vsz)
937 resid = vsz - uio->uio_offset;
939 error = vn_io_fault_pgmove(ma, uio->uio_offset & PAGE_MASK, resid, uio);
942 for (j = 0; j < i; j++) {
944 vm_page_reference(ma[j]);
945 vm_page_sunbusy(ma[j]);
948 vm_object_pip_wakeup(obj);
951 return (uio->uio_resid == 0 ? 0 : EJUSTRETURN);
955 do_vn_read_from_pgcache(struct vnode *vp, struct uio *uio, struct file *fp)
957 return ((vp->v_irflag & (VIRF_DOOMED | VIRF_PGREAD)) == VIRF_PGREAD &&
958 !mac_vnode_check_read_enabled() &&
959 uio->uio_resid <= ptoa(io_hold_cnt) && uio->uio_offset >= 0 &&
960 (fp->f_flag & O_DIRECT) == 0 && vn_io_pgcache_read_enable);
964 * File table vnode read routine.
967 vn_read(struct file *fp, struct uio *uio, struct ucred *active_cred, int flags,
975 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
977 KASSERT(flags & FOF_OFFSET, ("No FOF_OFFSET"));
979 if (do_vn_read_from_pgcache(vp, uio, fp)) {
980 error = vn_read_from_obj(vp, uio);
982 fp->f_nextoff[UIO_READ] = uio->uio_offset;
985 if (error != EJUSTRETURN)
989 if (fp->f_flag & FNONBLOCK)
991 if (fp->f_flag & O_DIRECT)
993 advice = get_advice(fp, uio);
994 vn_lock(vp, LK_SHARED | LK_RETRY);
997 case POSIX_FADV_NORMAL:
998 case POSIX_FADV_SEQUENTIAL:
999 case POSIX_FADV_NOREUSE:
1000 ioflag |= sequential_heuristic(uio, fp);
1002 case POSIX_FADV_RANDOM:
1003 /* Disable read-ahead for random I/O. */
1006 orig_offset = uio->uio_offset;
1009 error = mac_vnode_check_read(active_cred, fp->f_cred, vp);
1012 error = VOP_READ(vp, uio, ioflag, fp->f_cred);
1013 fp->f_nextoff[UIO_READ] = uio->uio_offset;
1015 if (error == 0 && advice == POSIX_FADV_NOREUSE &&
1016 orig_offset != uio->uio_offset)
1018 * Use POSIX_FADV_DONTNEED to flush pages and buffers
1019 * for the backing file after a POSIX_FADV_NOREUSE
1022 error = VOP_ADVISE(vp, orig_offset, uio->uio_offset - 1,
1023 POSIX_FADV_DONTNEED);
1028 * File table vnode write routine.
1031 vn_write(struct file *fp, struct uio *uio, struct ucred *active_cred, int flags,
1037 int error, ioflag, lock_flags;
1040 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
1042 KASSERT(flags & FOF_OFFSET, ("No FOF_OFFSET"));
1044 if (vp->v_type == VREG)
1047 if (vp->v_type == VREG && (fp->f_flag & O_APPEND))
1048 ioflag |= IO_APPEND;
1049 if (fp->f_flag & FNONBLOCK)
1050 ioflag |= IO_NDELAY;
1051 if (fp->f_flag & O_DIRECT)
1052 ioflag |= IO_DIRECT;
1053 if ((fp->f_flag & O_FSYNC) ||
1054 (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)))
1057 if (vp->v_type != VCHR &&
1058 (error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
1061 advice = get_advice(fp, uio);
1063 if (MNT_SHARED_WRITES(mp) ||
1064 (mp == NULL && MNT_SHARED_WRITES(vp->v_mount))) {
1065 lock_flags = LK_SHARED;
1067 lock_flags = LK_EXCLUSIVE;
1070 vn_lock(vp, lock_flags | LK_RETRY);
1072 case POSIX_FADV_NORMAL:
1073 case POSIX_FADV_SEQUENTIAL:
1074 case POSIX_FADV_NOREUSE:
1075 ioflag |= sequential_heuristic(uio, fp);
1077 case POSIX_FADV_RANDOM:
1078 /* XXX: Is this correct? */
1081 orig_offset = uio->uio_offset;
1084 error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
1087 error = VOP_WRITE(vp, uio, ioflag, fp->f_cred);
1088 fp->f_nextoff[UIO_WRITE] = uio->uio_offset;
1090 if (vp->v_type != VCHR)
1091 vn_finished_write(mp);
1092 if (error == 0 && advice == POSIX_FADV_NOREUSE &&
1093 orig_offset != uio->uio_offset)
1095 * Use POSIX_FADV_DONTNEED to flush pages and buffers
1096 * for the backing file after a POSIX_FADV_NOREUSE
1099 error = VOP_ADVISE(vp, orig_offset, uio->uio_offset - 1,
1100 POSIX_FADV_DONTNEED);
1106 * The vn_io_fault() is a wrapper around vn_read() and vn_write() to
1107 * prevent the following deadlock:
1109 * Assume that the thread A reads from the vnode vp1 into userspace
1110 * buffer buf1 backed by the pages of vnode vp2. If a page in buf1 is
1111 * currently not resident, then system ends up with the call chain
1112 * vn_read() -> VOP_READ(vp1) -> uiomove() -> [Page Fault] ->
1113 * vm_fault(buf1) -> vnode_pager_getpages(vp2) -> VOP_GETPAGES(vp2)
1114 * which establishes lock order vp1->vn_lock, then vp2->vn_lock.
1115 * If, at the same time, thread B reads from vnode vp2 into buffer buf2
1116 * backed by the pages of vnode vp1, and some page in buf2 is not
1117 * resident, we get a reversed order vp2->vn_lock, then vp1->vn_lock.
1119 * To prevent the lock order reversal and deadlock, vn_io_fault() does
1120 * not allow page faults to happen during VOP_READ() or VOP_WRITE().
1121 * Instead, it first tries to do the whole range i/o with pagefaults
1122 * disabled. If all pages in the i/o buffer are resident and mapped,
1123 * VOP will succeed (ignoring the genuine filesystem errors).
1124 * Otherwise, we get back EFAULT, and vn_io_fault() falls back to do
1125 * i/o in chunks, with all pages in the chunk prefaulted and held
1126 * using vm_fault_quick_hold_pages().
1128 * Filesystems using this deadlock avoidance scheme should use the
1129 * array of the held pages from uio, saved in the curthread->td_ma,
1130 * instead of doing uiomove(). A helper function
1131 * vn_io_fault_uiomove() converts uiomove request into
1132 * uiomove_fromphys() over td_ma array.
1134 * Since vnode locks do not cover the whole i/o anymore, rangelocks
1135 * make the current i/o request atomic with respect to other i/os and
1140 * Decode vn_io_fault_args and perform the corresponding i/o.
1143 vn_io_fault_doio(struct vn_io_fault_args *args, struct uio *uio,
1149 save = vm_fault_disable_pagefaults();
1150 switch (args->kind) {
1151 case VN_IO_FAULT_FOP:
1152 error = (args->args.fop_args.doio)(args->args.fop_args.fp,
1153 uio, args->cred, args->flags, td);
1155 case VN_IO_FAULT_VOP:
1156 if (uio->uio_rw == UIO_READ) {
1157 error = VOP_READ(args->args.vop_args.vp, uio,
1158 args->flags, args->cred);
1159 } else if (uio->uio_rw == UIO_WRITE) {
1160 error = VOP_WRITE(args->args.vop_args.vp, uio,
1161 args->flags, args->cred);
1165 panic("vn_io_fault_doio: unknown kind of io %d %d",
1166 args->kind, uio->uio_rw);
1168 vm_fault_enable_pagefaults(save);
1173 vn_io_fault_touch(char *base, const struct uio *uio)
1178 if (r == -1 || (uio->uio_rw == UIO_READ && subyte(base, r) == -1))
1184 vn_io_fault_prefault_user(const struct uio *uio)
1187 const struct iovec *iov;
1192 KASSERT(uio->uio_segflg == UIO_USERSPACE,
1193 ("vn_io_fault_prefault userspace"));
1197 resid = uio->uio_resid;
1198 base = iov->iov_base;
1201 error = vn_io_fault_touch(base, uio);
1204 if (len < PAGE_SIZE) {
1206 error = vn_io_fault_touch(base + len - 1, uio);
1211 if (++i >= uio->uio_iovcnt)
1213 iov = uio->uio_iov + i;
1214 base = iov->iov_base;
1226 * Common code for vn_io_fault(), agnostic to the kind of i/o request.
1227 * Uses vn_io_fault_doio() to make the call to an actual i/o function.
1228 * Used from vn_rdwr() and vn_io_fault(), which encode the i/o request
1229 * into args and call vn_io_fault1() to handle faults during the user
1230 * mode buffer accesses.
1233 vn_io_fault1(struct vnode *vp, struct uio *uio, struct vn_io_fault_args *args,
1236 vm_page_t ma[io_hold_cnt + 2];
1237 struct uio *uio_clone, short_uio;
1238 struct iovec short_iovec[1];
1239 vm_page_t *prev_td_ma;
1241 vm_offset_t addr, end;
1244 int error, cnt, saveheld, prev_td_ma_cnt;
1246 if (vn_io_fault_prefault) {
1247 error = vn_io_fault_prefault_user(uio);
1249 return (error); /* Or ignore ? */
1252 prot = uio->uio_rw == UIO_READ ? VM_PROT_WRITE : VM_PROT_READ;
1255 * The UFS follows IO_UNIT directive and replays back both
1256 * uio_offset and uio_resid if an error is encountered during the
1257 * operation. But, since the iovec may be already advanced,
1258 * uio is still in an inconsistent state.
1260 * Cache a copy of the original uio, which is advanced to the redo
1261 * point using UIO_NOCOPY below.
1263 uio_clone = cloneuio(uio);
1264 resid = uio->uio_resid;
1266 short_uio.uio_segflg = UIO_USERSPACE;
1267 short_uio.uio_rw = uio->uio_rw;
1268 short_uio.uio_td = uio->uio_td;
1270 error = vn_io_fault_doio(args, uio, td);
1271 if (error != EFAULT)
1274 atomic_add_long(&vn_io_faults_cnt, 1);
1275 uio_clone->uio_segflg = UIO_NOCOPY;
1276 uiomove(NULL, resid - uio->uio_resid, uio_clone);
1277 uio_clone->uio_segflg = uio->uio_segflg;
1279 saveheld = curthread_pflags_set(TDP_UIOHELD);
1280 prev_td_ma = td->td_ma;
1281 prev_td_ma_cnt = td->td_ma_cnt;
1283 while (uio_clone->uio_resid != 0) {
1284 len = uio_clone->uio_iov->iov_len;
1286 KASSERT(uio_clone->uio_iovcnt >= 1,
1287 ("iovcnt underflow"));
1288 uio_clone->uio_iov++;
1289 uio_clone->uio_iovcnt--;
1292 if (len > ptoa(io_hold_cnt))
1293 len = ptoa(io_hold_cnt);
1294 addr = (uintptr_t)uio_clone->uio_iov->iov_base;
1295 end = round_page(addr + len);
1300 cnt = atop(end - trunc_page(addr));
1302 * A perfectly misaligned address and length could cause
1303 * both the start and the end of the chunk to use partial
1304 * page. +2 accounts for such a situation.
1306 cnt = vm_fault_quick_hold_pages(&td->td_proc->p_vmspace->vm_map,
1307 addr, len, prot, ma, io_hold_cnt + 2);
1312 short_uio.uio_iov = &short_iovec[0];
1313 short_iovec[0].iov_base = (void *)addr;
1314 short_uio.uio_iovcnt = 1;
1315 short_uio.uio_resid = short_iovec[0].iov_len = len;
1316 short_uio.uio_offset = uio_clone->uio_offset;
1318 td->td_ma_cnt = cnt;
1320 error = vn_io_fault_doio(args, &short_uio, td);
1321 vm_page_unhold_pages(ma, cnt);
1322 adv = len - short_uio.uio_resid;
1324 uio_clone->uio_iov->iov_base =
1325 (char *)uio_clone->uio_iov->iov_base + adv;
1326 uio_clone->uio_iov->iov_len -= adv;
1327 uio_clone->uio_resid -= adv;
1328 uio_clone->uio_offset += adv;
1330 uio->uio_resid -= adv;
1331 uio->uio_offset += adv;
1333 if (error != 0 || adv == 0)
1336 td->td_ma = prev_td_ma;
1337 td->td_ma_cnt = prev_td_ma_cnt;
1338 curthread_pflags_restore(saveheld);
1340 free(uio_clone, M_IOV);
1345 vn_io_fault(struct file *fp, struct uio *uio, struct ucred *active_cred,
1346 int flags, struct thread *td)
1351 struct vn_io_fault_args args;
1354 doio = uio->uio_rw == UIO_READ ? vn_read : vn_write;
1358 * The ability to read(2) on a directory has historically been
1359 * allowed for all users, but this can and has been the source of
1360 * at least one security issue in the past. As such, it is now hidden
1361 * away behind a sysctl for those that actually need it to use it, and
1362 * restricted to root when it's turned on to make it relatively safe to
1363 * leave on for longer sessions of need.
1365 if (vp->v_type == VDIR) {
1366 KASSERT(uio->uio_rw == UIO_READ,
1367 ("illegal write attempted on a directory"));
1368 if (!vfs_allow_read_dir)
1370 if ((error = priv_check(td, PRIV_VFS_READ_DIR)) != 0)
1374 foffset_lock_uio(fp, uio, flags);
1375 if (do_vn_io_fault(vp, uio)) {
1376 args.kind = VN_IO_FAULT_FOP;
1377 args.args.fop_args.fp = fp;
1378 args.args.fop_args.doio = doio;
1379 args.cred = active_cred;
1380 args.flags = flags | FOF_OFFSET;
1381 if (uio->uio_rw == UIO_READ) {
1382 rl_cookie = vn_rangelock_rlock(vp, uio->uio_offset,
1383 uio->uio_offset + uio->uio_resid);
1384 } else if ((fp->f_flag & O_APPEND) != 0 ||
1385 (flags & FOF_OFFSET) == 0) {
1386 /* For appenders, punt and lock the whole range. */
1387 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
1389 rl_cookie = vn_rangelock_wlock(vp, uio->uio_offset,
1390 uio->uio_offset + uio->uio_resid);
1392 error = vn_io_fault1(vp, uio, &args, td);
1393 vn_rangelock_unlock(vp, rl_cookie);
1395 error = doio(fp, uio, active_cred, flags | FOF_OFFSET, td);
1397 foffset_unlock_uio(fp, uio, flags);
1402 * Helper function to perform the requested uiomove operation using
1403 * the held pages for io->uio_iov[0].iov_base buffer instead of
1404 * copyin/copyout. Access to the pages with uiomove_fromphys()
1405 * instead of iov_base prevents page faults that could occur due to
1406 * pmap_collect() invalidating the mapping created by
1407 * vm_fault_quick_hold_pages(), or pageout daemon, page laundry or
1408 * object cleanup revoking the write access from page mappings.
1410 * Filesystems specified MNTK_NO_IOPF shall use vn_io_fault_uiomove()
1411 * instead of plain uiomove().
1414 vn_io_fault_uiomove(char *data, int xfersize, struct uio *uio)
1416 struct uio transp_uio;
1417 struct iovec transp_iov[1];
1423 if ((td->td_pflags & TDP_UIOHELD) == 0 ||
1424 uio->uio_segflg != UIO_USERSPACE)
1425 return (uiomove(data, xfersize, uio));
1427 KASSERT(uio->uio_iovcnt == 1, ("uio_iovcnt %d", uio->uio_iovcnt));
1428 transp_iov[0].iov_base = data;
1429 transp_uio.uio_iov = &transp_iov[0];
1430 transp_uio.uio_iovcnt = 1;
1431 if (xfersize > uio->uio_resid)
1432 xfersize = uio->uio_resid;
1433 transp_uio.uio_resid = transp_iov[0].iov_len = xfersize;
1434 transp_uio.uio_offset = 0;
1435 transp_uio.uio_segflg = UIO_SYSSPACE;
1437 * Since transp_iov points to data, and td_ma page array
1438 * corresponds to original uio->uio_iov, we need to invert the
1439 * direction of the i/o operation as passed to
1440 * uiomove_fromphys().
1442 switch (uio->uio_rw) {
1444 transp_uio.uio_rw = UIO_READ;
1447 transp_uio.uio_rw = UIO_WRITE;
1450 transp_uio.uio_td = uio->uio_td;
1451 error = uiomove_fromphys(td->td_ma,
1452 ((vm_offset_t)uio->uio_iov->iov_base) & PAGE_MASK,
1453 xfersize, &transp_uio);
1454 adv = xfersize - transp_uio.uio_resid;
1456 (((vm_offset_t)uio->uio_iov->iov_base + adv) >> PAGE_SHIFT) -
1457 (((vm_offset_t)uio->uio_iov->iov_base) >> PAGE_SHIFT);
1459 KASSERT(td->td_ma_cnt >= pgadv, ("consumed pages %d %d", td->td_ma_cnt,
1461 td->td_ma_cnt -= pgadv;
1462 uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + adv;
1463 uio->uio_iov->iov_len -= adv;
1464 uio->uio_resid -= adv;
1465 uio->uio_offset += adv;
1470 vn_io_fault_pgmove(vm_page_t ma[], vm_offset_t offset, int xfersize,
1474 vm_offset_t iov_base;
1478 if ((td->td_pflags & TDP_UIOHELD) == 0 ||
1479 uio->uio_segflg != UIO_USERSPACE)
1480 return (uiomove_fromphys(ma, offset, xfersize, uio));
1482 KASSERT(uio->uio_iovcnt == 1, ("uio_iovcnt %d", uio->uio_iovcnt));
1483 cnt = xfersize > uio->uio_resid ? uio->uio_resid : xfersize;
1484 iov_base = (vm_offset_t)uio->uio_iov->iov_base;
1485 switch (uio->uio_rw) {
1487 pmap_copy_pages(td->td_ma, iov_base & PAGE_MASK, ma,
1491 pmap_copy_pages(ma, offset, td->td_ma, iov_base & PAGE_MASK,
1495 pgadv = ((iov_base + cnt) >> PAGE_SHIFT) - (iov_base >> PAGE_SHIFT);
1497 KASSERT(td->td_ma_cnt >= pgadv, ("consumed pages %d %d", td->td_ma_cnt,
1499 td->td_ma_cnt -= pgadv;
1500 uio->uio_iov->iov_base = (char *)(iov_base + cnt);
1501 uio->uio_iov->iov_len -= cnt;
1502 uio->uio_resid -= cnt;
1503 uio->uio_offset += cnt;
1508 * File table truncate routine.
1511 vn_truncate(struct file *fp, off_t length, struct ucred *active_cred,
1522 * Lock the whole range for truncation. Otherwise split i/o
1523 * might happen partly before and partly after the truncation.
1525 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
1526 error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
1529 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1530 AUDIT_ARG_VNODE1(vp);
1531 if (vp->v_type == VDIR) {
1536 error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
1540 error = vn_truncate_locked(vp, length, (fp->f_flag & O_FSYNC) != 0,
1544 vn_finished_write(mp);
1546 vn_rangelock_unlock(vp, rl_cookie);
1551 * Truncate a file that is already locked.
1554 vn_truncate_locked(struct vnode *vp, off_t length, bool sync,
1560 error = VOP_ADD_WRITECOUNT(vp, 1);
1563 vattr.va_size = length;
1565 vattr.va_vaflags |= VA_SYNC;
1566 error = VOP_SETATTR(vp, &vattr, cred);
1567 VOP_ADD_WRITECOUNT_CHECKED(vp, -1);
1573 * File table vnode stat routine.
1576 vn_statfile(struct file *fp, struct stat *sb, struct ucred *active_cred,
1579 struct vnode *vp = fp->f_vnode;
1582 vn_lock(vp, LK_SHARED | LK_RETRY);
1583 error = VOP_STAT(vp, sb, active_cred, fp->f_cred, td);
1590 * File table vnode ioctl routine.
1593 vn_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred,
1598 struct fiobmap2_arg *bmarg;
1602 switch (vp->v_type) {
1607 vn_lock(vp, LK_SHARED | LK_RETRY);
1608 error = VOP_GETATTR(vp, &vattr, active_cred);
1611 *(int *)data = vattr.va_size - fp->f_offset;
1614 bmarg = (struct fiobmap2_arg *)data;
1615 vn_lock(vp, LK_SHARED | LK_RETRY);
1617 error = mac_vnode_check_read(active_cred, fp->f_cred,
1621 error = VOP_BMAP(vp, bmarg->bn, NULL,
1622 &bmarg->bn, &bmarg->runp, &bmarg->runb);
1629 return (VOP_IOCTL(vp, com, data, fp->f_flag,
1634 return (VOP_IOCTL(vp, com, data, fp->f_flag,
1642 * File table vnode poll routine.
1645 vn_poll(struct file *fp, int events, struct ucred *active_cred,
1652 #if defined(MAC) || defined(AUDIT)
1653 if (AUDITING_TD(td) || mac_vnode_check_poll_enabled()) {
1654 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1655 AUDIT_ARG_VNODE1(vp);
1656 error = mac_vnode_check_poll(active_cred, fp->f_cred, vp);
1662 error = VOP_POLL(vp, events, fp->f_cred, td);
1667 * Acquire the requested lock and then check for validity. LK_RETRY
1668 * permits vn_lock to return doomed vnodes.
1670 static int __noinline
1671 _vn_lock_fallback(struct vnode *vp, int flags, const char *file, int line,
1675 KASSERT((flags & LK_RETRY) == 0 || error == 0,
1676 ("vn_lock: error %d incompatible with flags %#x", error, flags));
1679 VNASSERT(VN_IS_DOOMED(vp), vp, ("vnode not doomed"));
1681 if ((flags & LK_RETRY) == 0) {
1692 * Nothing to do if we got the lock.
1698 * Interlock was dropped by the call in _vn_lock.
1700 flags &= ~LK_INTERLOCK;
1702 error = VOP_LOCK1(vp, flags, file, line);
1703 } while (error != 0);
1708 _vn_lock(struct vnode *vp, int flags, const char *file, int line)
1712 VNASSERT((flags & LK_TYPE_MASK) != 0, vp,
1713 ("vn_lock: no locktype (%d passed)", flags));
1714 VNPASS(vp->v_holdcnt > 0, vp);
1715 error = VOP_LOCK1(vp, flags, file, line);
1716 if (__predict_false(error != 0 || VN_IS_DOOMED(vp)))
1717 return (_vn_lock_fallback(vp, flags, file, line, error));
1722 * File table vnode close routine.
1725 vn_closefile(struct file *fp, struct thread *td)
1733 fp->f_ops = &badfileops;
1734 ref= (fp->f_flag & FHASLOCK) != 0 && fp->f_type == DTYPE_VNODE;
1736 error = vn_close1(vp, fp->f_flag, fp->f_cred, td, ref);
1738 if (__predict_false(ref)) {
1739 lf.l_whence = SEEK_SET;
1742 lf.l_type = F_UNLCK;
1743 (void) VOP_ADVLOCK(vp, fp, F_UNLCK, &lf, F_FLOCK);
1750 * Preparing to start a filesystem write operation. If the operation is
1751 * permitted, then we bump the count of operations in progress and
1752 * proceed. If a suspend request is in progress, we wait until the
1753 * suspension is over, and then proceed.
1756 vn_start_write_refed(struct mount *mp, int flags, bool mplocked)
1760 if (__predict_true(!mplocked) && (flags & V_XSLEEP) == 0 &&
1761 vfs_op_thread_enter(mp)) {
1762 MPASS((mp->mnt_kern_flag & MNTK_SUSPEND) == 0);
1763 vfs_mp_count_add_pcpu(mp, writeopcount, 1);
1764 vfs_op_thread_exit(mp);
1769 mtx_assert(MNT_MTX(mp), MA_OWNED);
1776 * Check on status of suspension.
1778 if ((curthread->td_pflags & TDP_IGNSUSP) == 0 ||
1779 mp->mnt_susp_owner != curthread) {
1780 mflags = ((mp->mnt_vfc->vfc_flags & VFCF_SBDRY) != 0 ?
1781 (flags & PCATCH) : 0) | (PUSER - 1);
1782 while ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
1783 if (flags & V_NOWAIT) {
1784 error = EWOULDBLOCK;
1787 error = msleep(&mp->mnt_flag, MNT_MTX(mp), mflags,
1793 if (flags & V_XSLEEP)
1795 mp->mnt_writeopcount++;
1797 if (error != 0 || (flags & V_XSLEEP) != 0)
1804 vn_start_write(struct vnode *vp, struct mount **mpp, int flags)
1809 KASSERT((flags & V_MNTREF) == 0 || (*mpp != NULL && vp == NULL),
1810 ("V_MNTREF requires mp"));
1814 * If a vnode is provided, get and return the mount point that
1815 * to which it will write.
1818 if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
1820 if (error != EOPNOTSUPP)
1825 if ((mp = *mpp) == NULL)
1829 * VOP_GETWRITEMOUNT() returns with the mp refcount held through
1831 * As long as a vnode is not provided we need to acquire a
1832 * refcount for the provided mountpoint too, in order to
1833 * emulate a vfs_ref().
1835 if (vp == NULL && (flags & V_MNTREF) == 0)
1838 return (vn_start_write_refed(mp, flags, false));
1842 * Secondary suspension. Used by operations such as vop_inactive
1843 * routines that are needed by the higher level functions. These
1844 * are allowed to proceed until all the higher level functions have
1845 * completed (indicated by mnt_writeopcount dropping to zero). At that
1846 * time, these operations are halted until the suspension is over.
1849 vn_start_secondary_write(struct vnode *vp, struct mount **mpp, int flags)
1854 KASSERT((flags & V_MNTREF) == 0 || (*mpp != NULL && vp == NULL),
1855 ("V_MNTREF requires mp"));
1859 if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
1861 if (error != EOPNOTSUPP)
1867 * If we are not suspended or have not yet reached suspended
1868 * mode, then let the operation proceed.
1870 if ((mp = *mpp) == NULL)
1874 * VOP_GETWRITEMOUNT() returns with the mp refcount held through
1876 * As long as a vnode is not provided we need to acquire a
1877 * refcount for the provided mountpoint too, in order to
1878 * emulate a vfs_ref().
1881 if (vp == NULL && (flags & V_MNTREF) == 0)
1883 if ((mp->mnt_kern_flag & (MNTK_SUSPENDED | MNTK_SUSPEND2)) == 0) {
1884 mp->mnt_secondary_writes++;
1885 mp->mnt_secondary_accwrites++;
1889 if (flags & V_NOWAIT) {
1892 return (EWOULDBLOCK);
1895 * Wait for the suspension to finish.
1897 error = msleep(&mp->mnt_flag, MNT_MTX(mp), (PUSER - 1) | PDROP |
1898 ((mp->mnt_vfc->vfc_flags & VFCF_SBDRY) != 0 ? (flags & PCATCH) : 0),
1907 * Filesystem write operation has completed. If we are suspending and this
1908 * operation is the last one, notify the suspender that the suspension is
1912 vn_finished_write(struct mount *mp)
1919 if (vfs_op_thread_enter(mp)) {
1920 vfs_mp_count_sub_pcpu(mp, writeopcount, 1);
1921 vfs_mp_count_sub_pcpu(mp, ref, 1);
1922 vfs_op_thread_exit(mp);
1927 vfs_assert_mount_counters(mp);
1929 c = --mp->mnt_writeopcount;
1930 if (mp->mnt_vfs_ops == 0) {
1931 MPASS((mp->mnt_kern_flag & MNTK_SUSPEND) == 0);
1936 vfs_dump_mount_counters(mp);
1937 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 && c == 0)
1938 wakeup(&mp->mnt_writeopcount);
1943 * Filesystem secondary write operation has completed. If we are
1944 * suspending and this operation is the last one, notify the suspender
1945 * that the suspension is now in effect.
1948 vn_finished_secondary_write(struct mount *mp)
1954 mp->mnt_secondary_writes--;
1955 if (mp->mnt_secondary_writes < 0)
1956 panic("vn_finished_secondary_write: neg cnt");
1957 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 &&
1958 mp->mnt_secondary_writes <= 0)
1959 wakeup(&mp->mnt_secondary_writes);
1964 * Request a filesystem to suspend write operations.
1967 vfs_write_suspend(struct mount *mp, int flags)
1974 vfs_assert_mount_counters(mp);
1975 if (mp->mnt_susp_owner == curthread) {
1976 vfs_op_exit_locked(mp);
1980 while (mp->mnt_kern_flag & MNTK_SUSPEND)
1981 msleep(&mp->mnt_flag, MNT_MTX(mp), PUSER - 1, "wsuspfs", 0);
1984 * Unmount holds a write reference on the mount point. If we
1985 * own busy reference and drain for writers, we deadlock with
1986 * the reference draining in the unmount path. Callers of
1987 * vfs_write_suspend() must specify VS_SKIP_UNMOUNT if
1988 * vfs_busy() reference is owned and caller is not in the
1991 if ((flags & VS_SKIP_UNMOUNT) != 0 &&
1992 (mp->mnt_kern_flag & MNTK_UNMOUNT) != 0) {
1993 vfs_op_exit_locked(mp);
1998 mp->mnt_kern_flag |= MNTK_SUSPEND;
1999 mp->mnt_susp_owner = curthread;
2000 if (mp->mnt_writeopcount > 0)
2001 (void) msleep(&mp->mnt_writeopcount,
2002 MNT_MTX(mp), (PUSER - 1)|PDROP, "suspwt", 0);
2005 if ((error = VFS_SYNC(mp, MNT_SUSPEND)) != 0) {
2006 vfs_write_resume(mp, 0);
2007 /* vfs_write_resume does vfs_op_exit() for us */
2013 * Request a filesystem to resume write operations.
2016 vfs_write_resume(struct mount *mp, int flags)
2020 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
2021 KASSERT(mp->mnt_susp_owner == curthread, ("mnt_susp_owner"));
2022 mp->mnt_kern_flag &= ~(MNTK_SUSPEND | MNTK_SUSPEND2 |
2024 mp->mnt_susp_owner = NULL;
2025 wakeup(&mp->mnt_writeopcount);
2026 wakeup(&mp->mnt_flag);
2027 curthread->td_pflags &= ~TDP_IGNSUSP;
2028 if ((flags & VR_START_WRITE) != 0) {
2030 mp->mnt_writeopcount++;
2033 if ((flags & VR_NO_SUSPCLR) == 0)
2036 } else if ((flags & VR_START_WRITE) != 0) {
2038 vn_start_write_refed(mp, 0, true);
2045 * Helper loop around vfs_write_suspend() for filesystem unmount VFS
2049 vfs_write_suspend_umnt(struct mount *mp)
2053 KASSERT((curthread->td_pflags & TDP_IGNSUSP) == 0,
2054 ("vfs_write_suspend_umnt: recursed"));
2056 /* dounmount() already called vn_start_write(). */
2058 vn_finished_write(mp);
2059 error = vfs_write_suspend(mp, 0);
2061 vn_start_write(NULL, &mp, V_WAIT);
2065 if ((mp->mnt_kern_flag & MNTK_SUSPENDED) != 0)
2068 vn_start_write(NULL, &mp, V_WAIT);
2070 mp->mnt_kern_flag &= ~(MNTK_SUSPENDED | MNTK_SUSPEND2);
2071 wakeup(&mp->mnt_flag);
2073 curthread->td_pflags |= TDP_IGNSUSP;
2078 * Implement kqueues for files by translating it to vnode operation.
2081 vn_kqfilter(struct file *fp, struct knote *kn)
2084 return (VOP_KQFILTER(fp->f_vnode, kn));
2088 * Simplified in-kernel wrapper calls for extended attribute access.
2089 * Both calls pass in a NULL credential, authorizing as "kernel" access.
2090 * Set IO_NODELOCKED in ioflg if the vnode is already locked.
2093 vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace,
2094 const char *attrname, int *buflen, char *buf, struct thread *td)
2100 iov.iov_len = *buflen;
2103 auio.uio_iov = &iov;
2104 auio.uio_iovcnt = 1;
2105 auio.uio_rw = UIO_READ;
2106 auio.uio_segflg = UIO_SYSSPACE;
2108 auio.uio_offset = 0;
2109 auio.uio_resid = *buflen;
2111 if ((ioflg & IO_NODELOCKED) == 0)
2112 vn_lock(vp, LK_SHARED | LK_RETRY);
2114 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
2116 /* authorize attribute retrieval as kernel */
2117 error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL,
2120 if ((ioflg & IO_NODELOCKED) == 0)
2124 *buflen = *buflen - auio.uio_resid;
2131 * XXX failure mode if partially written?
2134 vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace,
2135 const char *attrname, int buflen, char *buf, struct thread *td)
2142 iov.iov_len = buflen;
2145 auio.uio_iov = &iov;
2146 auio.uio_iovcnt = 1;
2147 auio.uio_rw = UIO_WRITE;
2148 auio.uio_segflg = UIO_SYSSPACE;
2150 auio.uio_offset = 0;
2151 auio.uio_resid = buflen;
2153 if ((ioflg & IO_NODELOCKED) == 0) {
2154 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
2156 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2159 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
2161 /* authorize attribute setting as kernel */
2162 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, td);
2164 if ((ioflg & IO_NODELOCKED) == 0) {
2165 vn_finished_write(mp);
2173 vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace,
2174 const char *attrname, struct thread *td)
2179 if ((ioflg & IO_NODELOCKED) == 0) {
2180 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
2182 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2185 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
2187 /* authorize attribute removal as kernel */
2188 error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL, td);
2189 if (error == EOPNOTSUPP)
2190 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL,
2193 if ((ioflg & IO_NODELOCKED) == 0) {
2194 vn_finished_write(mp);
2202 vn_get_ino_alloc_vget(struct mount *mp, void *arg, int lkflags,
2206 return (VFS_VGET(mp, *(ino_t *)arg, lkflags, rvp));
2210 vn_vget_ino(struct vnode *vp, ino_t ino, int lkflags, struct vnode **rvp)
2213 return (vn_vget_ino_gen(vp, vn_get_ino_alloc_vget, &ino,
2218 vn_vget_ino_gen(struct vnode *vp, vn_get_ino_t alloc, void *alloc_arg,
2219 int lkflags, struct vnode **rvp)
2224 ASSERT_VOP_LOCKED(vp, "vn_vget_ino_get");
2226 ltype = VOP_ISLOCKED(vp);
2227 KASSERT(ltype == LK_EXCLUSIVE || ltype == LK_SHARED,
2228 ("vn_vget_ino: vp not locked"));
2229 error = vfs_busy(mp, MBF_NOWAIT);
2233 error = vfs_busy(mp, 0);
2234 vn_lock(vp, ltype | LK_RETRY);
2238 if (VN_IS_DOOMED(vp)) {
2244 error = alloc(mp, alloc_arg, lkflags, rvp);
2246 if (error != 0 || *rvp != vp)
2247 vn_lock(vp, ltype | LK_RETRY);
2248 if (VN_IS_DOOMED(vp)) {
2261 vn_rlimit_fsize(const struct vnode *vp, const struct uio *uio,
2265 if (vp->v_type != VREG || td == NULL)
2267 if ((uoff_t)uio->uio_offset + uio->uio_resid >
2268 lim_cur(td, RLIMIT_FSIZE)) {
2269 PROC_LOCK(td->td_proc);
2270 kern_psignal(td->td_proc, SIGXFSZ);
2271 PROC_UNLOCK(td->td_proc);
2278 vn_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
2285 vn_lock(vp, LK_SHARED | LK_RETRY);
2286 AUDIT_ARG_VNODE1(vp);
2289 return (setfmode(td, active_cred, vp, mode));
2293 vn_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
2300 vn_lock(vp, LK_SHARED | LK_RETRY);
2301 AUDIT_ARG_VNODE1(vp);
2304 return (setfown(td, active_cred, vp, uid, gid));
2308 vn_pages_remove(struct vnode *vp, vm_pindex_t start, vm_pindex_t end)
2312 if ((object = vp->v_object) == NULL)
2314 VM_OBJECT_WLOCK(object);
2315 vm_object_page_remove(object, start, end, 0);
2316 VM_OBJECT_WUNLOCK(object);
2320 vn_bmap_seekhole(struct vnode *vp, u_long cmd, off_t *off, struct ucred *cred)
2328 KASSERT(cmd == FIOSEEKHOLE || cmd == FIOSEEKDATA,
2329 ("Wrong command %lu", cmd));
2331 if (vn_lock(vp, LK_SHARED) != 0)
2333 if (vp->v_type != VREG) {
2337 error = VOP_GETATTR(vp, &va, cred);
2341 if (noff >= va.va_size) {
2345 bsize = vp->v_mount->mnt_stat.f_iosize;
2346 for (bn = noff / bsize; noff < va.va_size; bn++, noff += bsize -
2348 error = VOP_BMAP(vp, bn, NULL, &bnp, NULL, NULL);
2349 if (error == EOPNOTSUPP) {
2353 if ((bnp == -1 && cmd == FIOSEEKHOLE) ||
2354 (bnp != -1 && cmd == FIOSEEKDATA)) {
2361 if (noff > va.va_size)
2363 /* noff == va.va_size. There is an implicit hole at the end of file. */
2364 if (cmd == FIOSEEKDATA)
2374 vn_seek(struct file *fp, off_t offset, int whence, struct thread *td)
2379 off_t foffset, size;
2382 cred = td->td_ucred;
2384 foffset = foffset_lock(fp, 0);
2385 noneg = (vp->v_type != VCHR);
2391 (offset > 0 && foffset > OFF_MAX - offset))) {
2398 vn_lock(vp, LK_SHARED | LK_RETRY);
2399 error = VOP_GETATTR(vp, &vattr, cred);
2405 * If the file references a disk device, then fetch
2406 * the media size and use that to determine the ending
2409 if (vattr.va_size == 0 && vp->v_type == VCHR &&
2410 fo_ioctl(fp, DIOCGMEDIASIZE, &size, cred, td) == 0)
2411 vattr.va_size = size;
2413 (vattr.va_size > OFF_MAX ||
2414 (offset > 0 && vattr.va_size > OFF_MAX - offset))) {
2418 offset += vattr.va_size;
2423 error = fo_ioctl(fp, FIOSEEKDATA, &offset, cred, td);
2424 if (error == ENOTTY)
2428 error = fo_ioctl(fp, FIOSEEKHOLE, &offset, cred, td);
2429 if (error == ENOTTY)
2435 if (error == 0 && noneg && offset < 0)
2439 VFS_KNOTE_UNLOCKED(vp, 0);
2440 td->td_uretoff.tdu_off = offset;
2442 foffset_unlock(fp, offset, error != 0 ? FOF_NOUPDATE : 0);
2447 vn_utimes_perm(struct vnode *vp, struct vattr *vap, struct ucred *cred,
2453 * Grant permission if the caller is the owner of the file, or
2454 * the super-user, or has ACL_WRITE_ATTRIBUTES permission on
2455 * on the file. If the time pointer is null, then write
2456 * permission on the file is also sufficient.
2458 * From NFSv4.1, draft 21, 6.2.1.3.1, Discussion of Mask Attributes:
2459 * A user having ACL_WRITE_DATA or ACL_WRITE_ATTRIBUTES
2460 * will be allowed to set the times [..] to the current
2463 error = VOP_ACCESSX(vp, VWRITE_ATTRIBUTES, cred, td);
2464 if (error != 0 && (vap->va_vaflags & VA_UTIMES_NULL) != 0)
2465 error = VOP_ACCESS(vp, VWRITE, cred, td);
2470 vn_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
2475 if (fp->f_type == DTYPE_FIFO)
2476 kif->kf_type = KF_TYPE_FIFO;
2478 kif->kf_type = KF_TYPE_VNODE;
2481 FILEDESC_SUNLOCK(fdp);
2482 error = vn_fill_kinfo_vnode(vp, kif);
2484 FILEDESC_SLOCK(fdp);
2489 vn_fill_junk(struct kinfo_file *kif)
2494 * Simulate vn_fullpath returning changing values for a given
2495 * vp during e.g. coredump.
2497 len = (arc4random() % (sizeof(kif->kf_path) - 2)) + 1;
2498 olen = strlen(kif->kf_path);
2500 strcpy(&kif->kf_path[len - 1], "$");
2502 for (; olen < len; olen++)
2503 strcpy(&kif->kf_path[olen], "A");
2507 vn_fill_kinfo_vnode(struct vnode *vp, struct kinfo_file *kif)
2510 char *fullpath, *freepath;
2513 kif->kf_un.kf_file.kf_file_type = vntype_to_kinfo(vp->v_type);
2516 error = vn_fullpath(vp, &fullpath, &freepath);
2518 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path));
2520 if (freepath != NULL)
2521 free(freepath, M_TEMP);
2523 KFAIL_POINT_CODE(DEBUG_FP, fill_kinfo_vnode__random_path,
2528 * Retrieve vnode attributes.
2530 va.va_fsid = VNOVAL;
2532 vn_lock(vp, LK_SHARED | LK_RETRY);
2533 error = VOP_GETATTR(vp, &va, curthread->td_ucred);
2537 if (va.va_fsid != VNOVAL)
2538 kif->kf_un.kf_file.kf_file_fsid = va.va_fsid;
2540 kif->kf_un.kf_file.kf_file_fsid =
2541 vp->v_mount->mnt_stat.f_fsid.val[0];
2542 kif->kf_un.kf_file.kf_file_fsid_freebsd11 =
2543 kif->kf_un.kf_file.kf_file_fsid; /* truncate */
2544 kif->kf_un.kf_file.kf_file_fileid = va.va_fileid;
2545 kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode);
2546 kif->kf_un.kf_file.kf_file_size = va.va_size;
2547 kif->kf_un.kf_file.kf_file_rdev = va.va_rdev;
2548 kif->kf_un.kf_file.kf_file_rdev_freebsd11 =
2549 kif->kf_un.kf_file.kf_file_rdev; /* truncate */
2554 vn_mmap(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t size,
2555 vm_prot_t prot, vm_prot_t cap_maxprot, int flags, vm_ooffset_t foff,
2559 struct pmckern_map_in pkm;
2565 boolean_t writecounted;
2568 #if defined(COMPAT_FREEBSD7) || defined(COMPAT_FREEBSD6) || \
2569 defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4)
2571 * POSIX shared-memory objects are defined to have
2572 * kernel persistence, and are not defined to support
2573 * read(2)/write(2) -- or even open(2). Thus, we can
2574 * use MAP_ASYNC to trade on-disk coherence for speed.
2575 * The shm_open(3) library routine turns on the FPOSIXSHM
2576 * flag to request this behavior.
2578 if ((fp->f_flag & FPOSIXSHM) != 0)
2579 flags |= MAP_NOSYNC;
2584 * Ensure that file and memory protections are
2585 * compatible. Note that we only worry about
2586 * writability if mapping is shared; in this case,
2587 * current and max prot are dictated by the open file.
2588 * XXX use the vnode instead? Problem is: what
2589 * credentials do we use for determination? What if
2590 * proc does a setuid?
2593 if (mp != NULL && (mp->mnt_flag & MNT_NOEXEC) != 0) {
2594 maxprot = VM_PROT_NONE;
2595 if ((prot & VM_PROT_EXECUTE) != 0)
2598 maxprot = VM_PROT_EXECUTE;
2599 if ((fp->f_flag & FREAD) != 0)
2600 maxprot |= VM_PROT_READ;
2601 else if ((prot & VM_PROT_READ) != 0)
2605 * If we are sharing potential changes via MAP_SHARED and we
2606 * are trying to get write permission although we opened it
2607 * without asking for it, bail out.
2609 if ((flags & MAP_SHARED) != 0) {
2610 if ((fp->f_flag & FWRITE) != 0)
2611 maxprot |= VM_PROT_WRITE;
2612 else if ((prot & VM_PROT_WRITE) != 0)
2615 maxprot |= VM_PROT_WRITE;
2616 cap_maxprot |= VM_PROT_WRITE;
2618 maxprot &= cap_maxprot;
2621 * For regular files and shared memory, POSIX requires that
2622 * the value of foff be a legitimate offset within the data
2623 * object. In particular, negative offsets are invalid.
2624 * Blocking negative offsets and overflows here avoids
2625 * possible wraparound or user-level access into reserved
2626 * ranges of the data object later. In contrast, POSIX does
2627 * not dictate how offsets are used by device drivers, so in
2628 * the case of a device mapping a negative offset is passed
2635 foff < 0 || foff > OFF_MAX - size)
2638 writecounted = FALSE;
2639 error = vm_mmap_vnode(td, size, prot, &maxprot, &flags, vp,
2640 &foff, &object, &writecounted);
2643 error = vm_mmap_object(map, addr, size, prot, maxprot, flags, object,
2644 foff, writecounted, td);
2647 * If this mapping was accounted for in the vnode's
2648 * writecount, then undo that now.
2651 vm_pager_release_writecount(object, 0, size);
2652 vm_object_deallocate(object);
2655 /* Inform hwpmc(4) if an executable is being mapped. */
2656 if (PMC_HOOK_INSTALLED(PMC_FN_MMAP)) {
2657 if ((prot & VM_PROT_EXECUTE) != 0 && error == 0) {
2659 pkm.pm_address = (uintptr_t) *addr;
2660 PMC_CALL_HOOK_UNLOCKED(td, PMC_FN_MMAP, (void *) &pkm);
2668 vn_fsid(struct vnode *vp, struct vattr *va)
2672 f = &vp->v_mount->mnt_stat.f_fsid;
2673 va->va_fsid = (uint32_t)f->val[1];
2674 va->va_fsid <<= sizeof(f->val[1]) * NBBY;
2675 va->va_fsid += (uint32_t)f->val[0];
2679 vn_fsync_buf(struct vnode *vp, int waitfor)
2681 struct buf *bp, *nbp;
2684 int error, maxretry;
2687 maxretry = 10000; /* large, arbitrarily chosen */
2689 if (vp->v_type == VCHR) {
2691 mp = vp->v_rdev->si_mountpt;
2698 * MARK/SCAN initialization to avoid infinite loops.
2700 TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs) {
2701 bp->b_vflags &= ~BV_SCANNED;
2706 * Flush all dirty buffers associated with a vnode.
2709 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
2710 if ((bp->b_vflags & BV_SCANNED) != 0)
2712 bp->b_vflags |= BV_SCANNED;
2713 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL)) {
2714 if (waitfor != MNT_WAIT)
2717 LK_EXCLUSIVE | LK_INTERLOCK | LK_SLEEPFAIL,
2718 BO_LOCKPTR(bo)) != 0) {
2725 KASSERT(bp->b_bufobj == bo,
2726 ("bp %p wrong b_bufobj %p should be %p",
2727 bp, bp->b_bufobj, bo));
2728 if ((bp->b_flags & B_DELWRI) == 0)
2729 panic("fsync: not dirty");
2730 if ((vp->v_object != NULL) && (bp->b_flags & B_CLUSTEROK)) {
2736 if (maxretry < 1000)
2737 pause("dirty", hz < 1000 ? 1 : hz / 1000);
2743 * If synchronous the caller expects us to completely resolve all
2744 * dirty buffers in the system. Wait for in-progress I/O to
2745 * complete (which could include background bitmap writes), then
2746 * retry if dirty blocks still exist.
2748 if (waitfor == MNT_WAIT) {
2749 bufobj_wwait(bo, 0, 0);
2750 if (bo->bo_dirty.bv_cnt > 0) {
2752 * If we are unable to write any of these buffers
2753 * then we fail now rather than trying endlessly
2754 * to write them out.
2756 TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs)
2757 if ((error = bp->b_error) != 0)
2759 if ((mp != NULL && mp->mnt_secondary_writes > 0) ||
2760 (error == 0 && --maxretry >= 0))
2768 vn_printf(vp, "fsync: giving up on dirty (error = %d) ", error);
2774 * Copies a byte range from invp to outvp. Calls VOP_COPY_FILE_RANGE()
2775 * or vn_generic_copy_file_range() after rangelocking the byte ranges,
2776 * to do the actual copy.
2777 * vn_generic_copy_file_range() is factored out, so it can be called
2778 * from a VOP_COPY_FILE_RANGE() call as well, but handles vnodes from
2779 * different file systems.
2782 vn_copy_file_range(struct vnode *invp, off_t *inoffp, struct vnode *outvp,
2783 off_t *outoffp, size_t *lenp, unsigned int flags, struct ucred *incred,
2784 struct ucred *outcred, struct thread *fsize_td)
2788 uint64_t uvalin, uvalout;
2791 *lenp = 0; /* For error returns. */
2794 /* Do some sanity checks on the arguments. */
2799 if (invp->v_type == VDIR || outvp->v_type == VDIR)
2801 else if (*inoffp < 0 || uvalin > INT64_MAX || uvalin <
2802 (uint64_t)*inoffp || *outoffp < 0 || uvalout > INT64_MAX ||
2803 uvalout < (uint64_t)*outoffp || invp->v_type != VREG ||
2804 outvp->v_type != VREG)
2810 * If the two vnode are for the same file system, call
2811 * VOP_COPY_FILE_RANGE(), otherwise call vn_generic_copy_file_range()
2812 * which can handle copies across multiple file systems.
2815 if (invp->v_mount == outvp->v_mount)
2816 error = VOP_COPY_FILE_RANGE(invp, inoffp, outvp, outoffp,
2817 lenp, flags, incred, outcred, fsize_td);
2819 error = vn_generic_copy_file_range(invp, inoffp, outvp,
2820 outoffp, lenp, flags, incred, outcred, fsize_td);
2826 * Test len bytes of data starting at dat for all bytes == 0.
2827 * Return true if all bytes are zero, false otherwise.
2828 * Expects dat to be well aligned.
2831 mem_iszero(void *dat, int len)
2837 for (p = dat; len > 0; len -= sizeof(*p), p++) {
2838 if (len >= sizeof(*p)) {
2842 cp = (const char *)p;
2843 for (i = 0; i < len; i++, cp++)
2852 * Look for a hole in the output file and, if found, adjust *outoffp
2853 * and *xferp to skip past the hole.
2854 * *xferp is the entire hole length to be written and xfer2 is how many bytes
2855 * to be written as 0's upon return.
2858 vn_skip_hole(struct vnode *outvp, off_t xfer2, off_t *outoffp, off_t *xferp,
2859 off_t *dataoffp, off_t *holeoffp, struct ucred *cred)
2864 if (*holeoffp == 0 || *holeoffp <= *outoffp) {
2865 *dataoffp = *outoffp;
2866 error = VOP_IOCTL(outvp, FIOSEEKDATA, dataoffp, 0, cred,
2869 *holeoffp = *dataoffp;
2870 error = VOP_IOCTL(outvp, FIOSEEKHOLE, holeoffp, 0, cred,
2873 if (error != 0 || *holeoffp == *dataoffp) {
2875 * Since outvp is unlocked, it may be possible for
2876 * another thread to do a truncate(), lseek(), write()
2877 * creating a hole at startoff between the above
2878 * VOP_IOCTL() calls, if the other thread does not do
2880 * If that happens, *holeoffp == *dataoffp and finding
2881 * the hole has failed, so disable vn_skip_hole().
2883 *holeoffp = -1; /* Disable use of vn_skip_hole(). */
2886 KASSERT(*dataoffp >= *outoffp,
2887 ("vn_skip_hole: dataoff=%jd < outoff=%jd",
2888 (intmax_t)*dataoffp, (intmax_t)*outoffp));
2889 KASSERT(*holeoffp > *dataoffp,
2890 ("vn_skip_hole: holeoff=%jd <= dataoff=%jd",
2891 (intmax_t)*holeoffp, (intmax_t)*dataoffp));
2895 * If there is a hole before the data starts, advance *outoffp and
2896 * *xferp past the hole.
2898 if (*dataoffp > *outoffp) {
2899 delta = *dataoffp - *outoffp;
2900 if (delta >= *xferp) {
2901 /* Entire *xferp is a hole. */
2908 xfer2 = MIN(xfer2, *xferp);
2912 * If a hole starts before the end of this xfer2, reduce this xfer2 so
2913 * that the write ends at the start of the hole.
2914 * *holeoffp should always be greater than *outoffp, but for the
2915 * non-INVARIANTS case, check this to make sure xfer2 remains a sane
2918 if (*holeoffp > *outoffp && *holeoffp < *outoffp + xfer2)
2919 xfer2 = *holeoffp - *outoffp;
2924 * Write an xfer sized chunk to outvp in blksize blocks from dat.
2925 * dat is a maximum of blksize in length and can be written repeatedly in
2927 * If growfile == true, just grow the file via vn_truncate_locked() instead
2928 * of doing actual writes.
2929 * If checkhole == true, a hole is being punched, so skip over any hole
2930 * already in the output file.
2933 vn_write_outvp(struct vnode *outvp, char *dat, off_t outoff, off_t xfer,
2934 u_long blksize, bool growfile, bool checkhole, struct ucred *cred)
2937 off_t dataoff, holeoff, xfer2;
2941 * Loop around doing writes of blksize until write has been completed.
2942 * Lock/unlock on each loop iteration so that a bwillwrite() can be
2943 * done for each iteration, since the xfer argument can be very
2944 * large if there is a large hole to punch in the output file.
2949 xfer2 = MIN(xfer, blksize);
2952 * Punching a hole. Skip writing if there is
2953 * already a hole in the output file.
2955 xfer2 = vn_skip_hole(outvp, xfer2, &outoff, &xfer,
2956 &dataoff, &holeoff, cred);
2961 KASSERT(xfer2 > 0, ("vn_write_outvp: xfer2=%jd",
2966 error = vn_start_write(outvp, &mp, V_WAIT);
2968 if (MNT_SHARED_WRITES(mp))
2971 lckf = LK_EXCLUSIVE;
2972 error = vn_lock(outvp, lckf);
2976 error = vn_truncate_locked(outvp, outoff + xfer,
2979 error = vn_rdwr(UIO_WRITE, outvp, dat, xfer2,
2980 outoff, UIO_SYSSPACE, IO_NODELOCKED,
2981 curthread->td_ucred, cred, NULL, curthread);
2988 vn_finished_write(mp);
2989 } while (!growfile && xfer > 0 && error == 0);
2994 * Copy a byte range of one file to another. This function can handle the
2995 * case where invp and outvp are on different file systems.
2996 * It can also be called by a VOP_COPY_FILE_RANGE() to do the work, if there
2997 * is no better file system specific way to do it.
3000 vn_generic_copy_file_range(struct vnode *invp, off_t *inoffp,
3001 struct vnode *outvp, off_t *outoffp, size_t *lenp, unsigned int flags,
3002 struct ucred *incred, struct ucred *outcred, struct thread *fsize_td)
3007 off_t startoff, endoff, xfer, xfer2;
3010 bool cantseek, readzeros, eof, lastblock;
3012 size_t copylen, len, savlen;
3014 long holein, holeout;
3016 holein = holeout = 0;
3017 savlen = len = *lenp;
3021 error = vn_lock(invp, LK_SHARED);
3024 if (VOP_PATHCONF(invp, _PC_MIN_HOLE_SIZE, &holein) != 0)
3029 error = vn_start_write(outvp, &mp, V_WAIT);
3031 error = vn_lock(outvp, LK_EXCLUSIVE);
3034 * If fsize_td != NULL, do a vn_rlimit_fsize() call,
3035 * now that outvp is locked.
3037 if (fsize_td != NULL) {
3038 io.uio_offset = *outoffp;
3040 error = vn_rlimit_fsize(outvp, &io, fsize_td);
3044 if (VOP_PATHCONF(outvp, _PC_MIN_HOLE_SIZE, &holeout) != 0)
3047 * Holes that are past EOF do not need to be written as a block
3048 * of zero bytes. So, truncate the output file as far as
3049 * possible and then use va.va_size to decide if writing 0
3050 * bytes is necessary in the loop below.
3053 error = VOP_GETATTR(outvp, &va, outcred);
3054 if (error == 0 && va.va_size > *outoffp && va.va_size <=
3057 error = mac_vnode_check_write(curthread->td_ucred,
3061 error = vn_truncate_locked(outvp, *outoffp,
3064 va.va_size = *outoffp;
3069 vn_finished_write(mp);
3074 * Set the blksize to the larger of the hole sizes for invp and outvp.
3075 * If hole sizes aren't available, set the blksize to the larger
3076 * f_iosize of invp and outvp.
3077 * This code expects the hole sizes and f_iosizes to be powers of 2.
3078 * This value is clipped at 4Kbytes and 1Mbyte.
3080 blksize = MAX(holein, holeout);
3082 blksize = MAX(invp->v_mount->mnt_stat.f_iosize,
3083 outvp->v_mount->mnt_stat.f_iosize);
3086 else if (blksize > 1024 * 1024)
3087 blksize = 1024 * 1024;
3088 dat = malloc(blksize, M_TEMP, M_WAITOK);
3091 * If VOP_IOCTL(FIOSEEKHOLE) works for invp, use it and FIOSEEKDATA
3092 * to find holes. Otherwise, just scan the read block for all 0s
3093 * in the inner loop where the data copying is done.
3094 * Note that some file systems such as NFSv3, NFSv4.0 and NFSv4.1 may
3095 * support holes on the server, but do not support FIOSEEKHOLE.
3098 while (len > 0 && error == 0 && !eof) {
3099 endoff = 0; /* To shut up compilers. */
3105 * Find the next data area. If there is just a hole to EOF,
3106 * FIOSEEKDATA should fail and then we drop down into the
3107 * inner loop and create the hole on the outvp file.
3108 * (I do not know if any file system will report a hole to
3109 * EOF via FIOSEEKHOLE, but I am pretty sure FIOSEEKDATA
3110 * will fail for those file systems.)
3112 * For input files that don't support FIOSEEKDATA/FIOSEEKHOLE,
3113 * the code just falls through to the inner copy loop.
3117 error = VOP_IOCTL(invp, FIOSEEKDATA, &startoff, 0,
3121 error = VOP_IOCTL(invp, FIOSEEKHOLE, &endoff, 0,
3124 * Since invp is unlocked, it may be possible for
3125 * another thread to do a truncate(), lseek(), write()
3126 * creating a hole at startoff between the above
3127 * VOP_IOCTL() calls, if the other thread does not do
3129 * If that happens, startoff == endoff and finding
3130 * the hole has failed, so set an error.
3132 if (error == 0 && startoff == endoff)
3133 error = EINVAL; /* Any error. Reset to 0. */
3136 if (startoff > *inoffp) {
3137 /* Found hole before data block. */
3138 xfer = MIN(startoff - *inoffp, len);
3139 if (*outoffp < va.va_size) {
3140 /* Must write 0s to punch hole. */
3141 xfer2 = MIN(va.va_size - *outoffp,
3143 memset(dat, 0, MIN(xfer2, blksize));
3144 error = vn_write_outvp(outvp, dat,
3145 *outoffp, xfer2, blksize, false,
3146 holeout > 0, outcred);
3149 if (error == 0 && *outoffp + xfer >
3150 va.va_size && xfer == len)
3151 /* Grow last block. */
3152 error = vn_write_outvp(outvp, dat,
3153 *outoffp, xfer, blksize, true,
3161 copylen = MIN(len, endoff - startoff);
3173 * Set first xfer to end at a block boundary, so that
3174 * holes are more likely detected in the loop below via
3175 * the for all bytes 0 method.
3177 xfer -= (*inoffp % blksize);
3179 /* Loop copying the data block. */
3180 while (copylen > 0 && error == 0 && !eof) {
3183 error = vn_lock(invp, LK_SHARED);
3186 error = vn_rdwr(UIO_READ, invp, dat, xfer,
3187 startoff, UIO_SYSSPACE, IO_NODELOCKED,
3188 curthread->td_ucred, incred, &aresid,
3192 if (error == 0 && aresid > 0) {
3193 /* Stop the copy at EOF on the input file. */
3200 * Skip the write for holes past the initial EOF
3201 * of the output file, unless this is the last
3202 * write of the output file at EOF.
3204 readzeros = cantseek ? mem_iszero(dat, xfer) :
3208 if (!cantseek || *outoffp < va.va_size ||
3209 lastblock || !readzeros)
3210 error = vn_write_outvp(outvp, dat,
3211 *outoffp, xfer, blksize,
3212 readzeros && lastblock &&
3213 *outoffp >= va.va_size, false,
3227 *lenp = savlen - len;
3233 vn_fallocate(struct file *fp, off_t offset, off_t len, struct thread *td)
3237 off_t olen, ooffset;
3240 int audited_vnode1 = 0;
3244 if (vp->v_type != VREG)
3247 /* Allocating blocks may take a long time, so iterate. */
3254 error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
3257 error = vn_lock(vp, LK_EXCLUSIVE);
3259 vn_finished_write(mp);
3263 if (!audited_vnode1) {
3264 AUDIT_ARG_VNODE1(vp);
3269 error = mac_vnode_check_write(td->td_ucred, fp->f_cred, vp);
3272 error = VOP_ALLOCATE(vp, &offset, &len);
3274 vn_finished_write(mp);
3276 if (olen + ooffset != offset + len) {
3277 panic("offset + len changed from %jx/%jx to %jx/%jx",
3278 ooffset, olen, offset, len);
3280 if (error != 0 || len == 0)
3282 KASSERT(olen > len, ("Iteration did not make progress?"));