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>
68 #include <sys/dirent.h>
71 #include <sys/filio.h>
72 #include <sys/resourcevar.h>
73 #include <sys/rwlock.h>
76 #include <sys/sleepqueue.h>
77 #include <sys/sysctl.h>
78 #include <sys/ttycom.h>
80 #include <sys/syslog.h>
81 #include <sys/unistd.h>
83 #include <sys/ktrace.h>
85 #include <security/audit/audit.h>
86 #include <security/mac/mac_framework.h>
89 #include <vm/vm_extern.h>
91 #include <vm/vm_map.h>
92 #include <vm/vm_object.h>
93 #include <vm/vm_page.h>
94 #include <vm/vm_pager.h>
97 #include <sys/pmckern.h>
100 static fo_rdwr_t vn_read;
101 static fo_rdwr_t vn_write;
102 static fo_rdwr_t vn_io_fault;
103 static fo_truncate_t vn_truncate;
104 static fo_ioctl_t vn_ioctl;
105 static fo_poll_t vn_poll;
106 static fo_kqfilter_t vn_kqfilter;
107 static fo_close_t vn_closefile;
108 static fo_mmap_t vn_mmap;
109 static fo_fallocate_t vn_fallocate;
110 static fo_fspacectl_t vn_fspacectl;
112 struct fileops vnops = {
113 .fo_read = vn_io_fault,
114 .fo_write = vn_io_fault,
115 .fo_truncate = vn_truncate,
116 .fo_ioctl = vn_ioctl,
118 .fo_kqfilter = vn_kqfilter,
119 .fo_stat = vn_statfile,
120 .fo_close = vn_closefile,
121 .fo_chmod = vn_chmod,
122 .fo_chown = vn_chown,
123 .fo_sendfile = vn_sendfile,
125 .fo_fill_kinfo = vn_fill_kinfo,
127 .fo_fallocate = vn_fallocate,
128 .fo_fspacectl = vn_fspacectl,
129 .fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE
132 const u_int io_hold_cnt = 16;
133 static int vn_io_fault_enable = 1;
134 SYSCTL_INT(_debug, OID_AUTO, vn_io_fault_enable, CTLFLAG_RWTUN,
135 &vn_io_fault_enable, 0, "Enable vn_io_fault lock avoidance");
136 static int vn_io_fault_prefault = 0;
137 SYSCTL_INT(_debug, OID_AUTO, vn_io_fault_prefault, CTLFLAG_RWTUN,
138 &vn_io_fault_prefault, 0, "Enable vn_io_fault prefaulting");
139 static int vn_io_pgcache_read_enable = 1;
140 SYSCTL_INT(_debug, OID_AUTO, vn_io_pgcache_read_enable, CTLFLAG_RWTUN,
141 &vn_io_pgcache_read_enable, 0,
142 "Enable copying from page cache for reads, avoiding fs");
143 static u_long vn_io_faults_cnt;
144 SYSCTL_ULONG(_debug, OID_AUTO, vn_io_faults, CTLFLAG_RD,
145 &vn_io_faults_cnt, 0, "Count of vn_io_fault lock avoidance triggers");
147 static int vfs_allow_read_dir = 0;
148 SYSCTL_INT(_security_bsd, OID_AUTO, allow_read_dir, CTLFLAG_RW,
149 &vfs_allow_read_dir, 0,
150 "Enable read(2) of directory by root for filesystems that support it");
153 * Returns true if vn_io_fault mode of handling the i/o request should
157 do_vn_io_fault(struct vnode *vp, struct uio *uio)
161 return (uio->uio_segflg == UIO_USERSPACE && vp->v_type == VREG &&
162 (mp = vp->v_mount) != NULL &&
163 (mp->mnt_kern_flag & MNTK_NO_IOPF) != 0 && vn_io_fault_enable);
167 * Structure used to pass arguments to vn_io_fault1(), to do either
168 * file- or vnode-based I/O calls.
170 struct vn_io_fault_args {
178 struct fop_args_tag {
182 struct vop_args_tag {
188 static int vn_io_fault1(struct vnode *vp, struct uio *uio,
189 struct vn_io_fault_args *args, struct thread *td);
192 vn_open(struct nameidata *ndp, int *flagp, int cmode, struct file *fp)
194 struct thread *td = curthread;
196 return (vn_open_cred(ndp, flagp, cmode, 0, td->td_ucred, fp));
200 open2nameif(int fmode, u_int vn_open_flags)
204 res = ISOPEN | LOCKLEAF;
205 if ((fmode & O_RESOLVE_BENEATH) != 0)
207 if ((fmode & O_EMPTY_PATH) != 0)
209 if ((fmode & FREAD) != 0)
211 if ((fmode & FWRITE) != 0)
213 if ((vn_open_flags & VN_OPEN_NOAUDIT) == 0)
215 if ((vn_open_flags & VN_OPEN_NOCAPCHECK) != 0)
217 if ((vn_open_flags & VN_OPEN_WANTIOCTLCAPS) != 0)
218 res |= WANTIOCTLCAPS;
223 * Common code for vnode open operations via a name lookup.
224 * Lookup the vnode and invoke VOP_CREATE if needed.
225 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine.
227 * Note that this does NOT free nameidata for the successful case,
228 * due to the NDINIT being done elsewhere.
231 vn_open_cred(struct nameidata *ndp, int *flagp, int cmode, u_int vn_open_flags,
232 struct ucred *cred, struct file *fp)
237 struct vattr *vap = &vat;
244 if ((fmode & (O_CREAT | O_EXCL | O_DIRECTORY)) == (O_CREAT |
245 O_EXCL | O_DIRECTORY) ||
246 (fmode & (O_CREAT | O_EMPTY_PATH)) == (O_CREAT | O_EMPTY_PATH))
248 else if ((fmode & (O_CREAT | O_DIRECTORY)) == O_CREAT) {
249 ndp->ni_cnd.cn_nameiop = CREATE;
250 ndp->ni_cnd.cn_flags = open2nameif(fmode, vn_open_flags);
252 * Set NOCACHE to avoid flushing the cache when
253 * rolling in many files at once.
255 * Set NC_KEEPPOSENTRY to keep positive entries if they already
256 * exist despite NOCACHE.
258 ndp->ni_cnd.cn_flags |= LOCKPARENT | NOCACHE | NC_KEEPPOSENTRY;
259 if ((fmode & O_EXCL) == 0 && (fmode & O_NOFOLLOW) == 0)
260 ndp->ni_cnd.cn_flags |= FOLLOW;
261 if ((vn_open_flags & VN_OPEN_INVFS) == 0)
263 if ((error = namei(ndp)) != 0)
265 if (ndp->ni_vp == NULL) {
268 vap->va_mode = cmode;
270 vap->va_vaflags |= VA_EXCLUSIVE;
271 if (vn_start_write(ndp->ni_dvp, &mp, V_NOWAIT) != 0) {
274 if ((error = vn_start_write(NULL, &mp,
275 V_XSLEEP | V_PCATCH)) != 0)
280 if ((vn_open_flags & VN_OPEN_NAMECACHE) != 0)
281 ndp->ni_cnd.cn_flags |= MAKEENTRY;
283 error = mac_vnode_check_create(cred, ndp->ni_dvp,
287 error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp,
290 if (error == 0 && (fmode & O_EXCL) != 0 &&
291 (fmode & (O_EXLOCK | O_SHLOCK)) != 0) {
293 vp->v_iflag |= VI_FOPENING;
297 VOP_VPUT_PAIR(ndp->ni_dvp, error == 0 ? &vp : NULL,
299 vn_finished_write(mp);
302 if (error == ERELOOKUP) {
310 if (ndp->ni_dvp == ndp->ni_vp)
316 if (fmode & O_EXCL) {
320 if (vp->v_type == VDIR) {
327 ndp->ni_cnd.cn_nameiop = LOOKUP;
328 ndp->ni_cnd.cn_flags = open2nameif(fmode, vn_open_flags);
329 ndp->ni_cnd.cn_flags |= (fmode & O_NOFOLLOW) != 0 ? NOFOLLOW :
331 if ((fmode & FWRITE) == 0)
332 ndp->ni_cnd.cn_flags |= LOCKSHARED;
333 if ((error = namei(ndp)) != 0)
337 error = vn_open_vnode(vp, fmode, cred, curthread, fp);
340 vp->v_iflag &= ~VI_FOPENING;
357 vn_open_vnode_advlock(struct vnode *vp, int fmode, struct file *fp)
360 int error, lock_flags, type;
362 ASSERT_VOP_LOCKED(vp, "vn_open_vnode_advlock");
363 if ((fmode & (O_EXLOCK | O_SHLOCK)) == 0)
365 KASSERT(fp != NULL, ("open with flock requires fp"));
366 if (fp->f_type != DTYPE_NONE && fp->f_type != DTYPE_VNODE)
369 lock_flags = VOP_ISLOCKED(vp);
372 lf.l_whence = SEEK_SET;
375 lf.l_type = (fmode & O_EXLOCK) != 0 ? F_WRLCK : F_RDLCK;
377 if ((fmode & FNONBLOCK) == 0)
379 if ((fmode & (O_CREAT | O_EXCL)) == (O_CREAT | O_EXCL))
381 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, type);
383 fp->f_flag |= FHASLOCK;
385 vn_lock(vp, lock_flags | LK_RETRY);
390 * Common code for vnode open operations once a vnode is located.
391 * Check permissions, and call the VOP_OPEN routine.
394 vn_open_vnode(struct vnode *vp, int fmode, struct ucred *cred,
395 struct thread *td, struct file *fp)
400 if (vp->v_type == VLNK) {
401 if ((fmode & O_PATH) == 0 || (fmode & FEXEC) != 0)
404 if (vp->v_type != VDIR && fmode & O_DIRECTORY)
408 if ((fmode & O_PATH) == 0) {
409 if (vp->v_type == VSOCK)
411 if ((fmode & (FWRITE | O_TRUNC)) != 0) {
412 if (vp->v_type == VDIR)
416 if ((fmode & FREAD) != 0)
418 if ((fmode & O_APPEND) && (fmode & FWRITE))
421 if ((fmode & O_CREAT) != 0)
425 if ((fmode & FEXEC) != 0)
428 if ((fmode & O_VERIFY) != 0)
430 error = mac_vnode_check_open(cred, vp, accmode);
434 accmode &= ~(VCREAT | VVERIFY);
436 if ((fmode & O_CREAT) == 0 && accmode != 0) {
437 error = VOP_ACCESS(vp, accmode, cred, td);
441 if ((fmode & O_PATH) != 0) {
442 if (vp->v_type != VFIFO && vp->v_type != VSOCK &&
443 VOP_ACCESS(vp, VREAD, cred, td) == 0)
444 fp->f_flag |= FKQALLOWED;
448 if (vp->v_type == VFIFO && VOP_ISLOCKED(vp) != LK_EXCLUSIVE)
449 vn_lock(vp, LK_UPGRADE | LK_RETRY);
450 error = VOP_OPEN(vp, fmode, cred, td, fp);
454 error = vn_open_vnode_advlock(vp, fmode, fp);
455 if (error == 0 && (fmode & FWRITE) != 0) {
456 error = VOP_ADD_WRITECOUNT(vp, 1);
458 CTR3(KTR_VFS, "%s: vp %p v_writecount increased to %d",
459 __func__, vp, vp->v_writecount);
464 * Error from advlock or VOP_ADD_WRITECOUNT() still requires
465 * calling VOP_CLOSE() to pair with earlier VOP_OPEN().
470 * Arrange the call by having fdrop() to use
471 * vn_closefile(). This is to satisfy
472 * filesystems like devfs or tmpfs, which
473 * override fo_close().
475 fp->f_flag |= FOPENFAILED;
477 if (fp->f_ops == &badfileops) {
478 fp->f_type = DTYPE_VNODE;
484 * If there is no fp, due to kernel-mode open,
485 * we can call VOP_CLOSE() now.
487 if ((vp->v_type == VFIFO ||
488 !MNT_EXTENDED_SHARED(vp->v_mount)) &&
489 VOP_ISLOCKED(vp) != LK_EXCLUSIVE)
490 vn_lock(vp, LK_UPGRADE | LK_RETRY);
491 (void)VOP_CLOSE(vp, fmode & (FREAD | FWRITE | FEXEC),
496 ASSERT_VOP_LOCKED(vp, "vn_open_vnode");
502 * Check for write permissions on the specified vnode.
503 * Prototype text segments cannot be written.
507 vn_writechk(struct vnode *vp)
510 ASSERT_VOP_LOCKED(vp, "vn_writechk");
512 * If there's shared text associated with
513 * the vnode, try to free it up once. If
514 * we fail, we can't allow writing.
526 vn_close1(struct vnode *vp, int flags, struct ucred *file_cred,
527 struct thread *td, bool keep_ref)
530 int error, lock_flags;
532 lock_flags = vp->v_type != VFIFO && MNT_EXTENDED_SHARED(vp->v_mount) ?
533 LK_SHARED : LK_EXCLUSIVE;
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);
543 error = VOP_CLOSE(vp, flags, file_cred, td);
548 vn_finished_write(mp);
553 vn_close(struct vnode *vp, int flags, struct ucred *file_cred,
557 return (vn_close1(vp, flags, file_cred, td, false));
561 * Heuristic to detect sequential operation.
564 sequential_heuristic(struct uio *uio, struct file *fp)
568 ASSERT_VOP_LOCKED(fp->f_vnode, __func__);
571 if (fp->f_flag & FRDAHEAD)
572 return (fp->f_seqcount[rw] << IO_SEQSHIFT);
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.
581 if ((uio->uio_offset == 0 && fp->f_seqcount[rw] > 0) ||
582 uio->uio_offset == fp->f_nextoff[rw]) {
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.
592 if (uio->uio_resid >= IO_SEQMAX * 16384)
593 fp->f_seqcount[rw] = IO_SEQMAX;
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;
599 return (fp->f_seqcount[rw] << IO_SEQSHIFT);
602 /* Not sequential. Quickly draw-down sequentiality. */
603 if (fp->f_seqcount[rw] > 1)
604 fp->f_seqcount[rw] = 1;
606 fp->f_seqcount[rw] = 0;
611 * Package up an I/O request on a vnode into a uio and do it.
614 vn_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)
623 struct vn_io_fault_args args;
624 int error, lock_flags;
626 if (offset < 0 && vp->v_type != VCHR)
628 auio.uio_iov = &aiov;
630 aiov.iov_base = base;
632 auio.uio_resid = len;
633 auio.uio_offset = offset;
634 auio.uio_segflg = segflg;
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,
644 } else if ((ioflg & IO_APPEND) != 0) {
645 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
647 rl_cookie = vn_rangelock_wlock(vp, offset,
653 if (rw == UIO_WRITE) {
654 if (vp->v_type != VCHR &&
655 (error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH))
658 lock_flags = vn_lktype_write(mp, vp);
660 lock_flags = LK_SHARED;
661 vn_lock(vp, lock_flags | LK_RETRY);
665 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
667 if ((ioflg & IO_NOMACCHECK) == 0) {
669 error = mac_vnode_check_read(active_cred, file_cred,
672 error = mac_vnode_check_write(active_cred, file_cred,
677 if (file_cred != NULL)
681 if (do_vn_io_fault(vp, &auio)) {
682 args.kind = VN_IO_FAULT_VOP;
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);
694 *aresid = auio.uio_resid;
696 if (auio.uio_resid && error == 0)
698 if ((ioflg & IO_NODELOCKED) == 0) {
701 vn_finished_write(mp);
704 if (rl_cookie != NULL)
705 vn_rangelock_unlock(vp, rl_cookie);
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).
718 vn_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)
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
734 chunk = MAXBSIZE - (uoff_t)offset % MAXBSIZE;
738 if (rw != UIO_READ && vp->v_type == VREG)
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 */
747 base = (char *)base + chunk;
748 kern_yield(PRI_USER);
751 *aresid = len + iaresid;
755 #if OFF_MAX <= LONG_MAX
757 foffset_lock(struct file *fp, int flags)
759 volatile short *flagsp;
763 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
765 if ((flags & FOF_NOLOCK) != 0)
766 return (atomic_load_long(&fp->f_offset));
769 * According to McKusick the vn lock was protecting f_offset here.
770 * It is now protected by the FOFFSET_LOCKED flag.
772 flagsp = &fp->f_vnread_flags;
773 if (atomic_cmpset_acq_16(flagsp, 0, FOFFSET_LOCKED))
774 return (atomic_load_long(&fp->f_offset));
776 sleepq_lock(&fp->f_vnread_flags);
777 state = atomic_load_16(flagsp);
779 if ((state & FOFFSET_LOCKED) == 0) {
780 if (!atomic_fcmpset_acq_16(flagsp, &state,
785 if ((state & FOFFSET_LOCK_WAITING) == 0) {
786 if (!atomic_fcmpset_acq_16(flagsp, &state,
787 state | FOFFSET_LOCK_WAITING))
791 sleepq_add(&fp->f_vnread_flags, NULL, "vofflock", 0, 0);
792 sleepq_wait(&fp->f_vnread_flags, PUSER -1);
794 sleepq_lock(&fp->f_vnread_flags);
795 state = atomic_load_16(flagsp);
797 res = atomic_load_long(&fp->f_offset);
798 sleepq_release(&fp->f_vnread_flags);
803 foffset_unlock(struct file *fp, off_t val, int flags)
805 volatile short *flagsp;
808 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
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;
817 if ((flags & FOF_NOLOCK) != 0)
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))
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);
835 foffset_lock(struct file *fp, int flags)
840 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
842 mtxp = mtx_pool_find(mtxpool_sleep, fp);
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,
850 fp->f_vnread_flags |= FOFFSET_LOCKED;
858 foffset_unlock(struct file *fp, off_t val, int flags)
862 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
864 mtxp = mtx_pool_find(mtxpool_sleep, fp);
866 if ((flags & FOF_NOUPDATE) == 0)
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;
884 foffset_lock_uio(struct file *fp, struct uio *uio, int flags)
887 if ((flags & FOF_OFFSET) == 0)
888 uio->uio_offset = foffset_lock(fp, flags);
892 foffset_unlock_uio(struct file *fp, struct uio *uio, int flags)
895 if ((flags & FOF_OFFSET) == 0)
896 foffset_unlock(fp, uio->uio_offset, flags);
900 get_advice(struct file *fp, struct uio *uio)
905 ret = POSIX_FADV_NORMAL;
906 if (fp->f_advice == NULL || fp->f_vnode->v_type != VREG)
909 mtxp = mtx_pool_find(mtxpool_sleep, fp);
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;
920 get_write_ioflag(struct file *fp)
928 mp = atomic_load_ptr(&vp->v_mount);
930 if ((fp->f_flag & O_DIRECT) != 0)
933 if ((fp->f_flag & O_FSYNC) != 0 ||
934 (mp != NULL && (mp->mnt_flag & MNT_SYNCHRONOUS) != 0))
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.
942 if ((fp->f_flag & O_DSYNC) != 0)
943 ioflag |= IO_SYNC | IO_DATASYNC;
949 vn_read_from_obj(struct vnode *vp, struct uio *uio)
952 vm_page_t ma[io_hold_cnt + 2];
957 MPASS(uio->uio_resid <= ptoa(io_hold_cnt + 2));
958 obj = atomic_load_ptr(&vp->v_object);
960 return (EJUSTRETURN);
963 * Depends on type stability of vm_objects.
965 vm_object_pip_add(obj, 1);
966 if ((obj->flags & OBJ_DEAD) != 0) {
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.
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.
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 |
992 * Skip invalid pages. Valid mask can be partial only
993 * at EOF, and we clip later.
995 if (vm_page_none_valid(ma[i])) {
996 vm_page_sunbusy(ma[i]);
1004 error = EJUSTRETURN;
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.
1013 if (VN_IS_DOOMED(vp)) {
1014 error = EJUSTRETURN;
1018 resid = PAGE_SIZE - (uio->uio_offset & PAGE_MASK) + ptoa(i - 1);
1019 if (resid > uio->uio_resid)
1020 resid = uio->uio_resid;
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.
1028 #if defined(__powerpc__) && !defined(__powerpc64__)
1029 vsz = obj->un_pager.vnp.vnp_size;
1031 vsz = atomic_load_64(&obj->un_pager.vnp.vnp_size);
1033 if (uio->uio_offset >= vsz) {
1034 error = EJUSTRETURN;
1037 if (uio->uio_offset + resid > vsz)
1038 resid = vsz - uio->uio_offset;
1040 error = vn_io_fault_pgmove(ma, uio->uio_offset & PAGE_MASK, resid, uio);
1043 for (j = 0; j < i; j++) {
1045 vm_page_reference(ma[j]);
1046 vm_page_sunbusy(ma[j]);
1049 vm_object_pip_wakeup(obj);
1052 return (uio->uio_resid == 0 ? 0 : EJUSTRETURN);
1056 * File table vnode read routine.
1059 vn_read(struct file *fp, struct uio *uio, struct ucred *active_cred, int flags,
1067 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
1069 KASSERT(flags & FOF_OFFSET, ("No FOF_OFFSET"));
1072 if (fp->f_flag & FNONBLOCK)
1073 ioflag |= IO_NDELAY;
1074 if (fp->f_flag & O_DIRECT)
1075 ioflag |= IO_DIRECT;
1078 * Try to read from page cache. VIRF_DOOMED check is racy but
1079 * allows us to avoid unneeded work outright.
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);
1085 fp->f_nextoff[UIO_READ] = uio->uio_offset;
1088 if (error != EJUSTRETURN)
1092 advice = get_advice(fp, uio);
1093 vn_lock(vp, LK_SHARED | LK_RETRY);
1096 case POSIX_FADV_NORMAL:
1097 case POSIX_FADV_SEQUENTIAL:
1098 case POSIX_FADV_NOREUSE:
1099 ioflag |= sequential_heuristic(uio, fp);
1101 case POSIX_FADV_RANDOM:
1102 /* Disable read-ahead for random I/O. */
1105 orig_offset = uio->uio_offset;
1108 error = mac_vnode_check_read(active_cred, fp->f_cred, vp);
1111 error = VOP_READ(vp, uio, ioflag, fp->f_cred);
1112 fp->f_nextoff[UIO_READ] = uio->uio_offset;
1114 if (error == 0 && advice == POSIX_FADV_NOREUSE &&
1115 orig_offset != uio->uio_offset)
1117 * Use POSIX_FADV_DONTNEED to flush pages and buffers
1118 * for the backing file after a POSIX_FADV_NOREUSE
1121 error = VOP_ADVISE(vp, orig_offset, uio->uio_offset - 1,
1122 POSIX_FADV_DONTNEED);
1127 * File table vnode write routine.
1130 vn_write(struct file *fp, struct uio *uio, struct ucred *active_cred, int flags,
1138 bool need_finished_write;
1140 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
1142 KASSERT(flags & FOF_OFFSET, ("No FOF_OFFSET"));
1144 if (vp->v_type == VREG)
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);
1154 need_finished_write = false;
1155 if (vp->v_type != VCHR) {
1156 error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH);
1159 need_finished_write = true;
1162 advice = get_advice(fp, uio);
1164 vn_lock(vp, vn_lktype_write(mp, vp) | LK_RETRY);
1166 case POSIX_FADV_NORMAL:
1167 case POSIX_FADV_SEQUENTIAL:
1168 case POSIX_FADV_NOREUSE:
1169 ioflag |= sequential_heuristic(uio, fp);
1171 case POSIX_FADV_RANDOM:
1172 /* XXX: Is this correct? */
1175 orig_offset = uio->uio_offset;
1178 error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
1181 error = VOP_WRITE(vp, uio, ioflag, fp->f_cred);
1182 fp->f_nextoff[UIO_WRITE] = uio->uio_offset;
1184 if (need_finished_write)
1185 vn_finished_write(mp);
1186 if (error == 0 && advice == POSIX_FADV_NOREUSE &&
1187 orig_offset != uio->uio_offset)
1189 * Use POSIX_FADV_DONTNEED to flush pages and buffers
1190 * for the backing file after a POSIX_FADV_NOREUSE
1193 error = VOP_ADVISE(vp, orig_offset, uio->uio_offset - 1,
1194 POSIX_FADV_DONTNEED);
1200 * The vn_io_fault() is a wrapper around vn_read() and vn_write() to
1201 * prevent the following deadlock:
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.
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().
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.
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
1234 * Decode vn_io_fault_args and perform the corresponding i/o.
1237 vn_io_fault_doio(struct vn_io_fault_args *args, struct uio *uio,
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);
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);
1259 panic("vn_io_fault_doio: unknown kind of io %d %d",
1260 args->kind, uio->uio_rw);
1262 vm_fault_enable_pagefaults(save);
1267 vn_io_fault_touch(char *base, const struct uio *uio)
1272 if (r == -1 || (uio->uio_rw == UIO_READ && subyte(base, r) == -1))
1278 vn_io_fault_prefault_user(const struct uio *uio)
1281 const struct iovec *iov;
1286 KASSERT(uio->uio_segflg == UIO_USERSPACE,
1287 ("vn_io_fault_prefault userspace"));
1291 resid = uio->uio_resid;
1292 base = iov->iov_base;
1295 error = vn_io_fault_touch(base, uio);
1298 if (len < PAGE_SIZE) {
1300 error = vn_io_fault_touch(base + len - 1, uio);
1305 if (++i >= uio->uio_iovcnt)
1307 iov = uio->uio_iov + i;
1308 base = iov->iov_base;
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.
1327 vn_io_fault1(struct vnode *vp, struct uio *uio, struct vn_io_fault_args *args,
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;
1335 vm_offset_t addr, end;
1338 int error, cnt, saveheld, prev_td_ma_cnt;
1340 if (vn_io_fault_prefault) {
1341 error = vn_io_fault_prefault_user(uio);
1343 return (error); /* Or ignore ? */
1346 prot = uio->uio_rw == UIO_READ ? VM_PROT_WRITE : VM_PROT_READ;
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.
1354 * Cache a copy of the original uio, which is advanced to the redo
1355 * point using UIO_NOCOPY below.
1357 uio_clone = cloneuio(uio);
1358 resid = uio->uio_resid;
1360 short_uio.uio_segflg = UIO_USERSPACE;
1361 short_uio.uio_rw = uio->uio_rw;
1362 short_uio.uio_td = uio->uio_td;
1364 error = vn_io_fault_doio(args, uio, td);
1365 if (error != EFAULT)
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;
1373 saveheld = curthread_pflags_set(TDP_UIOHELD);
1374 prev_td_ma = td->td_ma;
1375 prev_td_ma_cnt = td->td_ma_cnt;
1377 while (uio_clone->uio_resid != 0) {
1378 len = uio_clone->uio_iov->iov_len;
1380 KASSERT(uio_clone->uio_iovcnt >= 1,
1381 ("iovcnt underflow"));
1382 uio_clone->uio_iov++;
1383 uio_clone->uio_iovcnt--;
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);
1395 * A perfectly misaligned address and length could cause
1396 * both the start and the end of the chunk to use partial
1397 * page. +2 accounts for such a situation.
1399 cnt = vm_fault_quick_hold_pages(&td->td_proc->p_vmspace->vm_map,
1400 addr, len, prot, ma, io_hold_cnt + 2);
1405 short_uio.uio_iov = &short_iovec[0];
1406 short_iovec[0].iov_base = (void *)addr;
1407 short_uio.uio_iovcnt = 1;
1408 short_uio.uio_resid = short_iovec[0].iov_len = len;
1409 short_uio.uio_offset = uio_clone->uio_offset;
1411 td->td_ma_cnt = cnt;
1413 error = vn_io_fault_doio(args, &short_uio, td);
1414 vm_page_unhold_pages(ma, cnt);
1415 adv = len - short_uio.uio_resid;
1417 uio_clone->uio_iov->iov_base =
1418 (char *)uio_clone->uio_iov->iov_base + adv;
1419 uio_clone->uio_iov->iov_len -= adv;
1420 uio_clone->uio_resid -= adv;
1421 uio_clone->uio_offset += adv;
1423 uio->uio_resid -= adv;
1424 uio->uio_offset += adv;
1426 if (error != 0 || adv == 0)
1429 td->td_ma = prev_td_ma;
1430 td->td_ma_cnt = prev_td_ma_cnt;
1431 curthread_pflags_restore(saveheld);
1433 free(uio_clone, M_IOV);
1438 vn_io_fault(struct file *fp, struct uio *uio, struct ucred *active_cred,
1439 int flags, struct thread *td)
1444 struct vn_io_fault_args args;
1446 bool do_io_fault, do_rangelock;
1448 doio = uio->uio_rw == UIO_READ ? vn_read : vn_write;
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.
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)
1464 if ((error = priv_check(td, PRIV_VFS_READ_DIR)) != 0)
1468 do_io_fault = do_vn_io_fault(vp, uio);
1469 do_rangelock = do_io_fault || (vn_irflag_read(vp) & VIRF_PGREAD) != 0;
1470 foffset_lock_uio(fp, uio, flags);
1472 if (uio->uio_rw == UIO_READ) {
1473 rl_cookie = vn_rangelock_rlock(vp, uio->uio_offset,
1474 uio->uio_offset + uio->uio_resid);
1475 } else if ((fp->f_flag & O_APPEND) != 0 ||
1476 (flags & FOF_OFFSET) == 0) {
1477 /* For appenders, punt and lock the whole range. */
1478 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
1480 rl_cookie = vn_rangelock_wlock(vp, uio->uio_offset,
1481 uio->uio_offset + uio->uio_resid);
1485 args.kind = VN_IO_FAULT_FOP;
1486 args.args.fop_args.fp = fp;
1487 args.args.fop_args.doio = doio;
1488 args.cred = active_cred;
1489 args.flags = flags | FOF_OFFSET;
1490 error = vn_io_fault1(vp, uio, &args, td);
1492 error = doio(fp, uio, active_cred, flags | FOF_OFFSET, td);
1495 vn_rangelock_unlock(vp, rl_cookie);
1496 foffset_unlock_uio(fp, uio, flags);
1501 * Helper function to perform the requested uiomove operation using
1502 * the held pages for io->uio_iov[0].iov_base buffer instead of
1503 * copyin/copyout. Access to the pages with uiomove_fromphys()
1504 * instead of iov_base prevents page faults that could occur due to
1505 * pmap_collect() invalidating the mapping created by
1506 * vm_fault_quick_hold_pages(), or pageout daemon, page laundry or
1507 * object cleanup revoking the write access from page mappings.
1509 * Filesystems specified MNTK_NO_IOPF shall use vn_io_fault_uiomove()
1510 * instead of plain uiomove().
1513 vn_io_fault_uiomove(char *data, int xfersize, struct uio *uio)
1515 struct uio transp_uio;
1516 struct iovec transp_iov[1];
1522 if ((td->td_pflags & TDP_UIOHELD) == 0 ||
1523 uio->uio_segflg != UIO_USERSPACE)
1524 return (uiomove(data, xfersize, uio));
1526 KASSERT(uio->uio_iovcnt == 1, ("uio_iovcnt %d", uio->uio_iovcnt));
1527 transp_iov[0].iov_base = data;
1528 transp_uio.uio_iov = &transp_iov[0];
1529 transp_uio.uio_iovcnt = 1;
1530 if (xfersize > uio->uio_resid)
1531 xfersize = uio->uio_resid;
1532 transp_uio.uio_resid = transp_iov[0].iov_len = xfersize;
1533 transp_uio.uio_offset = 0;
1534 transp_uio.uio_segflg = UIO_SYSSPACE;
1536 * Since transp_iov points to data, and td_ma page array
1537 * corresponds to original uio->uio_iov, we need to invert the
1538 * direction of the i/o operation as passed to
1539 * uiomove_fromphys().
1541 switch (uio->uio_rw) {
1543 transp_uio.uio_rw = UIO_READ;
1546 transp_uio.uio_rw = UIO_WRITE;
1549 transp_uio.uio_td = uio->uio_td;
1550 error = uiomove_fromphys(td->td_ma,
1551 ((vm_offset_t)uio->uio_iov->iov_base) & PAGE_MASK,
1552 xfersize, &transp_uio);
1553 adv = xfersize - transp_uio.uio_resid;
1555 (((vm_offset_t)uio->uio_iov->iov_base + adv) >> PAGE_SHIFT) -
1556 (((vm_offset_t)uio->uio_iov->iov_base) >> PAGE_SHIFT);
1558 KASSERT(td->td_ma_cnt >= pgadv, ("consumed pages %d %d", td->td_ma_cnt,
1560 td->td_ma_cnt -= pgadv;
1561 uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + adv;
1562 uio->uio_iov->iov_len -= adv;
1563 uio->uio_resid -= adv;
1564 uio->uio_offset += adv;
1569 vn_io_fault_pgmove(vm_page_t ma[], vm_offset_t offset, int xfersize,
1573 vm_offset_t iov_base;
1577 if ((td->td_pflags & TDP_UIOHELD) == 0 ||
1578 uio->uio_segflg != UIO_USERSPACE)
1579 return (uiomove_fromphys(ma, offset, xfersize, uio));
1581 KASSERT(uio->uio_iovcnt == 1, ("uio_iovcnt %d", uio->uio_iovcnt));
1582 cnt = xfersize > uio->uio_resid ? uio->uio_resid : xfersize;
1583 iov_base = (vm_offset_t)uio->uio_iov->iov_base;
1584 switch (uio->uio_rw) {
1586 pmap_copy_pages(td->td_ma, iov_base & PAGE_MASK, ma,
1590 pmap_copy_pages(ma, offset, td->td_ma, iov_base & PAGE_MASK,
1594 pgadv = ((iov_base + cnt) >> PAGE_SHIFT) - (iov_base >> PAGE_SHIFT);
1596 KASSERT(td->td_ma_cnt >= pgadv, ("consumed pages %d %d", td->td_ma_cnt,
1598 td->td_ma_cnt -= pgadv;
1599 uio->uio_iov->iov_base = (char *)(iov_base + cnt);
1600 uio->uio_iov->iov_len -= cnt;
1601 uio->uio_resid -= cnt;
1602 uio->uio_offset += cnt;
1607 * File table truncate routine.
1610 vn_truncate(struct file *fp, off_t length, struct ucred *active_cred,
1622 * Lock the whole range for truncation. Otherwise split i/o
1623 * might happen partly before and partly after the truncation.
1625 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
1626 error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH);
1629 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1630 AUDIT_ARG_VNODE1(vp);
1631 if (vp->v_type == VDIR) {
1636 error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
1640 error = vn_truncate_locked(vp, length, (fp->f_flag & O_FSYNC) != 0,
1644 vn_finished_write(mp);
1646 vn_rangelock_unlock(vp, rl_cookie);
1647 if (error == ERELOOKUP)
1653 * Truncate a file that is already locked.
1656 vn_truncate_locked(struct vnode *vp, off_t length, bool sync,
1662 error = VOP_ADD_WRITECOUNT(vp, 1);
1665 vattr.va_size = length;
1667 vattr.va_vaflags |= VA_SYNC;
1668 error = VOP_SETATTR(vp, &vattr, cred);
1669 VOP_ADD_WRITECOUNT_CHECKED(vp, -1);
1675 * File table vnode stat routine.
1678 vn_statfile(struct file *fp, struct stat *sb, struct ucred *active_cred)
1680 struct vnode *vp = fp->f_vnode;
1683 vn_lock(vp, LK_SHARED | LK_RETRY);
1684 error = VOP_STAT(vp, sb, active_cred, fp->f_cred);
1691 * File table vnode ioctl routine.
1694 vn_ioctl(struct file *fp, u_long com, void *data, struct ucred *active_cred,
1698 struct fiobmap2_arg *bmarg;
1703 switch (vp->v_type) {
1708 error = vn_getsize(vp, &size, active_cred);
1710 *(int *)data = size - fp->f_offset;
1713 bmarg = (struct fiobmap2_arg *)data;
1714 vn_lock(vp, LK_SHARED | LK_RETRY);
1716 error = mac_vnode_check_read(active_cred, fp->f_cred,
1720 error = VOP_BMAP(vp, bmarg->bn, NULL,
1721 &bmarg->bn, &bmarg->runp, &bmarg->runb);
1728 return (VOP_IOCTL(vp, com, data, fp->f_flag,
1733 return (VOP_IOCTL(vp, com, data, fp->f_flag,
1741 * File table vnode poll routine.
1744 vn_poll(struct file *fp, int events, struct ucred *active_cred,
1751 #if defined(MAC) || defined(AUDIT)
1752 if (AUDITING_TD(td) || mac_vnode_check_poll_enabled()) {
1753 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1754 AUDIT_ARG_VNODE1(vp);
1755 error = mac_vnode_check_poll(active_cred, fp->f_cred, vp);
1761 error = VOP_POLL(vp, events, fp->f_cred, td);
1766 * Acquire the requested lock and then check for validity. LK_RETRY
1767 * permits vn_lock to return doomed vnodes.
1769 static int __noinline
1770 _vn_lock_fallback(struct vnode *vp, int flags, const char *file, int line,
1774 KASSERT((flags & LK_RETRY) == 0 || error == 0,
1775 ("vn_lock: error %d incompatible with flags %#x", error, flags));
1778 VNASSERT(VN_IS_DOOMED(vp), vp, ("vnode not doomed"));
1780 if ((flags & LK_RETRY) == 0) {
1791 * Nothing to do if we got the lock.
1797 * Interlock was dropped by the call in _vn_lock.
1799 flags &= ~LK_INTERLOCK;
1801 error = VOP_LOCK1(vp, flags, file, line);
1802 } while (error != 0);
1807 _vn_lock(struct vnode *vp, int flags, const char *file, int line)
1811 VNASSERT((flags & LK_TYPE_MASK) != 0, vp,
1812 ("vn_lock: no locktype (%d passed)", flags));
1813 VNPASS(vp->v_holdcnt > 0, vp);
1814 error = VOP_LOCK1(vp, flags, file, line);
1815 if (__predict_false(error != 0 || VN_IS_DOOMED(vp)))
1816 return (_vn_lock_fallback(vp, flags, file, line, error));
1821 * File table vnode close routine.
1824 vn_closefile(struct file *fp, struct thread *td)
1832 fp->f_ops = &badfileops;
1833 ref = (fp->f_flag & FHASLOCK) != 0;
1835 error = vn_close1(vp, fp->f_flag, fp->f_cred, td, ref);
1837 if (__predict_false(ref)) {
1838 lf.l_whence = SEEK_SET;
1841 lf.l_type = F_UNLCK;
1842 (void) VOP_ADVLOCK(vp, fp, F_UNLCK, &lf, F_FLOCK);
1849 * Preparing to start a filesystem write operation. If the operation is
1850 * permitted, then we bump the count of operations in progress and
1851 * proceed. If a suspend request is in progress, we wait until the
1852 * suspension is over, and then proceed.
1855 vn_start_write_refed(struct mount *mp, int flags, bool mplocked)
1857 struct mount_pcpu *mpcpu;
1860 if (__predict_true(!mplocked) && (flags & V_XSLEEP) == 0 &&
1861 vfs_op_thread_enter(mp, mpcpu)) {
1862 MPASS((mp->mnt_kern_flag & MNTK_SUSPEND) == 0);
1863 vfs_mp_count_add_pcpu(mpcpu, writeopcount, 1);
1864 vfs_op_thread_exit(mp, mpcpu);
1869 mtx_assert(MNT_MTX(mp), MA_OWNED);
1876 * Check on status of suspension.
1878 if ((curthread->td_pflags & TDP_IGNSUSP) == 0 ||
1879 mp->mnt_susp_owner != curthread) {
1881 if ((mp->mnt_vfc->vfc_flags & VFCF_SBDRY) != 0) {
1882 if (flags & V_PCATCH)
1885 mflags |= (PUSER - 1);
1886 while ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
1887 if ((flags & V_NOWAIT) != 0) {
1888 error = EWOULDBLOCK;
1891 error = msleep(&mp->mnt_flag, MNT_MTX(mp), mflags,
1897 if ((flags & V_XSLEEP) != 0)
1899 mp->mnt_writeopcount++;
1901 if (error != 0 || (flags & V_XSLEEP) != 0)
1908 vn_start_write(struct vnode *vp, struct mount **mpp, int flags)
1913 KASSERT((flags & ~V_VALID_FLAGS) == 0,
1914 ("%s: invalid flags passed %d\n", __func__, flags));
1918 * If a vnode is provided, get and return the mount point that
1919 * to which it will write.
1922 if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
1924 if (error != EOPNOTSUPP)
1929 if ((mp = *mpp) == NULL)
1933 * VOP_GETWRITEMOUNT() returns with the mp refcount held through
1935 * As long as a vnode is not provided we need to acquire a
1936 * refcount for the provided mountpoint too, in order to
1937 * emulate a vfs_ref().
1942 error = vn_start_write_refed(mp, flags, false);
1943 if (error != 0 && (flags & V_NOWAIT) == 0)
1949 * Secondary suspension. Used by operations such as vop_inactive
1950 * routines that are needed by the higher level functions. These
1951 * are allowed to proceed until all the higher level functions have
1952 * completed (indicated by mnt_writeopcount dropping to zero). At that
1953 * time, these operations are halted until the suspension is over.
1956 vn_start_secondary_write(struct vnode *vp, struct mount **mpp, int flags)
1961 KASSERT((flags & (~V_VALID_FLAGS | V_XSLEEP)) == 0,
1962 ("%s: invalid flags passed %d\n", __func__, flags));
1966 if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
1968 if (error != EOPNOTSUPP)
1974 * If we are not suspended or have not yet reached suspended
1975 * mode, then let the operation proceed.
1977 if ((mp = *mpp) == NULL)
1981 * VOP_GETWRITEMOUNT() returns with the mp refcount held through
1983 * As long as a vnode is not provided we need to acquire a
1984 * refcount for the provided mountpoint too, in order to
1985 * emulate a vfs_ref().
1990 if ((mp->mnt_kern_flag & (MNTK_SUSPENDED | MNTK_SUSPEND2)) == 0) {
1991 mp->mnt_secondary_writes++;
1992 mp->mnt_secondary_accwrites++;
1996 if ((flags & V_NOWAIT) != 0) {
2000 return (EWOULDBLOCK);
2003 * Wait for the suspension to finish.
2006 if ((mp->mnt_vfc->vfc_flags & VFCF_SBDRY) != 0) {
2007 if ((flags & V_PCATCH) != 0)
2010 mflags |= (PUSER - 1) | PDROP;
2011 error = msleep(&mp->mnt_flag, MNT_MTX(mp), mflags, "suspfs", 0);
2020 * Filesystem write operation has completed. If we are suspending and this
2021 * operation is the last one, notify the suspender that the suspension is
2025 vn_finished_write(struct mount *mp)
2027 struct mount_pcpu *mpcpu;
2033 if (vfs_op_thread_enter(mp, mpcpu)) {
2034 vfs_mp_count_sub_pcpu(mpcpu, writeopcount, 1);
2035 vfs_mp_count_sub_pcpu(mpcpu, ref, 1);
2036 vfs_op_thread_exit(mp, mpcpu);
2041 vfs_assert_mount_counters(mp);
2043 c = --mp->mnt_writeopcount;
2044 if (mp->mnt_vfs_ops == 0) {
2045 MPASS((mp->mnt_kern_flag & MNTK_SUSPEND) == 0);
2050 vfs_dump_mount_counters(mp);
2051 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 && c == 0)
2052 wakeup(&mp->mnt_writeopcount);
2057 * Filesystem secondary write operation has completed. If we are
2058 * suspending and this operation is the last one, notify the suspender
2059 * that the suspension is now in effect.
2062 vn_finished_secondary_write(struct mount *mp)
2068 mp->mnt_secondary_writes--;
2069 if (mp->mnt_secondary_writes < 0)
2070 panic("vn_finished_secondary_write: neg cnt");
2071 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 &&
2072 mp->mnt_secondary_writes <= 0)
2073 wakeup(&mp->mnt_secondary_writes);
2078 * Request a filesystem to suspend write operations.
2081 vfs_write_suspend(struct mount *mp, int flags)
2088 vfs_assert_mount_counters(mp);
2089 if (mp->mnt_susp_owner == curthread) {
2090 vfs_op_exit_locked(mp);
2094 while (mp->mnt_kern_flag & MNTK_SUSPEND)
2095 msleep(&mp->mnt_flag, MNT_MTX(mp), PUSER - 1, "wsuspfs", 0);
2098 * Unmount holds a write reference on the mount point. If we
2099 * own busy reference and drain for writers, we deadlock with
2100 * the reference draining in the unmount path. Callers of
2101 * vfs_write_suspend() must specify VS_SKIP_UNMOUNT if
2102 * vfs_busy() reference is owned and caller is not in the
2105 if ((flags & VS_SKIP_UNMOUNT) != 0 &&
2106 (mp->mnt_kern_flag & MNTK_UNMOUNT) != 0) {
2107 vfs_op_exit_locked(mp);
2112 mp->mnt_kern_flag |= MNTK_SUSPEND;
2113 mp->mnt_susp_owner = curthread;
2114 if (mp->mnt_writeopcount > 0)
2115 (void) msleep(&mp->mnt_writeopcount,
2116 MNT_MTX(mp), (PUSER - 1)|PDROP, "suspwt", 0);
2119 if ((error = VFS_SYNC(mp, MNT_SUSPEND)) != 0) {
2120 vfs_write_resume(mp, 0);
2121 /* vfs_write_resume does vfs_op_exit() for us */
2127 * Request a filesystem to resume write operations.
2130 vfs_write_resume(struct mount *mp, int flags)
2134 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
2135 KASSERT(mp->mnt_susp_owner == curthread, ("mnt_susp_owner"));
2136 mp->mnt_kern_flag &= ~(MNTK_SUSPEND | MNTK_SUSPEND2 |
2138 mp->mnt_susp_owner = NULL;
2139 wakeup(&mp->mnt_writeopcount);
2140 wakeup(&mp->mnt_flag);
2141 curthread->td_pflags &= ~TDP_IGNSUSP;
2142 if ((flags & VR_START_WRITE) != 0) {
2144 mp->mnt_writeopcount++;
2147 if ((flags & VR_NO_SUSPCLR) == 0)
2150 } else if ((flags & VR_START_WRITE) != 0) {
2152 vn_start_write_refed(mp, 0, true);
2159 * Helper loop around vfs_write_suspend() for filesystem unmount VFS
2163 vfs_write_suspend_umnt(struct mount *mp)
2167 KASSERT((curthread->td_pflags & TDP_IGNSUSP) == 0,
2168 ("vfs_write_suspend_umnt: recursed"));
2170 /* dounmount() already called vn_start_write(). */
2172 vn_finished_write(mp);
2173 error = vfs_write_suspend(mp, 0);
2175 vn_start_write(NULL, &mp, V_WAIT);
2179 if ((mp->mnt_kern_flag & MNTK_SUSPENDED) != 0)
2182 vn_start_write(NULL, &mp, V_WAIT);
2184 mp->mnt_kern_flag &= ~(MNTK_SUSPENDED | MNTK_SUSPEND2);
2185 wakeup(&mp->mnt_flag);
2187 curthread->td_pflags |= TDP_IGNSUSP;
2192 * Implement kqueues for files by translating it to vnode operation.
2195 vn_kqfilter(struct file *fp, struct knote *kn)
2198 return (VOP_KQFILTER(fp->f_vnode, kn));
2202 vn_kqfilter_opath(struct file *fp, struct knote *kn)
2204 if ((fp->f_flag & FKQALLOWED) == 0)
2206 return (vn_kqfilter(fp, kn));
2210 * Simplified in-kernel wrapper calls for extended attribute access.
2211 * Both calls pass in a NULL credential, authorizing as "kernel" access.
2212 * Set IO_NODELOCKED in ioflg if the vnode is already locked.
2215 vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace,
2216 const char *attrname, int *buflen, char *buf, struct thread *td)
2222 iov.iov_len = *buflen;
2225 auio.uio_iov = &iov;
2226 auio.uio_iovcnt = 1;
2227 auio.uio_rw = UIO_READ;
2228 auio.uio_segflg = UIO_SYSSPACE;
2230 auio.uio_offset = 0;
2231 auio.uio_resid = *buflen;
2233 if ((ioflg & IO_NODELOCKED) == 0)
2234 vn_lock(vp, LK_SHARED | LK_RETRY);
2236 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
2238 /* authorize attribute retrieval as kernel */
2239 error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL,
2242 if ((ioflg & IO_NODELOCKED) == 0)
2246 *buflen = *buflen - auio.uio_resid;
2253 * XXX failure mode if partially written?
2256 vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace,
2257 const char *attrname, int buflen, char *buf, struct thread *td)
2264 iov.iov_len = buflen;
2267 auio.uio_iov = &iov;
2268 auio.uio_iovcnt = 1;
2269 auio.uio_rw = UIO_WRITE;
2270 auio.uio_segflg = UIO_SYSSPACE;
2272 auio.uio_offset = 0;
2273 auio.uio_resid = buflen;
2275 if ((ioflg & IO_NODELOCKED) == 0) {
2276 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
2278 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2281 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
2283 /* authorize attribute setting as kernel */
2284 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, td);
2286 if ((ioflg & IO_NODELOCKED) == 0) {
2287 vn_finished_write(mp);
2295 vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace,
2296 const char *attrname, struct thread *td)
2301 if ((ioflg & IO_NODELOCKED) == 0) {
2302 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
2304 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
2307 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
2309 /* authorize attribute removal as kernel */
2310 error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL, td);
2311 if (error == EOPNOTSUPP)
2312 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL,
2315 if ((ioflg & IO_NODELOCKED) == 0) {
2316 vn_finished_write(mp);
2324 vn_get_ino_alloc_vget(struct mount *mp, void *arg, int lkflags,
2328 return (VFS_VGET(mp, *(ino_t *)arg, lkflags, rvp));
2332 vn_vget_ino(struct vnode *vp, ino_t ino, int lkflags, struct vnode **rvp)
2335 return (vn_vget_ino_gen(vp, vn_get_ino_alloc_vget, &ino,
2340 vn_vget_ino_gen(struct vnode *vp, vn_get_ino_t alloc, void *alloc_arg,
2341 int lkflags, struct vnode **rvp)
2346 ASSERT_VOP_LOCKED(vp, "vn_vget_ino_get");
2348 ltype = VOP_ISLOCKED(vp);
2349 KASSERT(ltype == LK_EXCLUSIVE || ltype == LK_SHARED,
2350 ("vn_vget_ino: vp not locked"));
2351 error = vfs_busy(mp, MBF_NOWAIT);
2355 error = vfs_busy(mp, 0);
2356 vn_lock(vp, ltype | LK_RETRY);
2360 if (VN_IS_DOOMED(vp)) {
2366 error = alloc(mp, alloc_arg, lkflags, rvp);
2368 if (error != 0 || *rvp != vp)
2369 vn_lock(vp, ltype | LK_RETRY);
2370 if (VN_IS_DOOMED(vp)) {
2383 vn_send_sigxfsz(struct proc *p)
2386 kern_psignal(p, SIGXFSZ);
2391 vn_rlimit_trunc(u_quad_t size, struct thread *td)
2393 if (size <= lim_cur(td, RLIMIT_FSIZE))
2395 vn_send_sigxfsz(td->td_proc);
2400 vn_rlimit_fsizex1(const struct vnode *vp, struct uio *uio, off_t maxfsz,
2401 bool adj, struct thread *td)
2406 if (vp->v_type != VREG)
2410 * Handle file system maximum file size.
2412 if (maxfsz != 0 && uio->uio_offset + uio->uio_resid > maxfsz) {
2413 if (!adj || uio->uio_offset >= maxfsz)
2415 uio->uio_resid = maxfsz - uio->uio_offset;
2419 * This is kernel write (e.g. vnode_pager) or accounting
2420 * write, ignore limit.
2422 if (td == NULL || (td->td_pflags2 & TDP2_ACCT) != 0)
2426 * Calculate file size limit.
2428 ktr_write = (td->td_pflags & TDP_INKTRACE) != 0;
2429 lim = __predict_false(ktr_write) ? td->td_ktr_io_lim :
2430 lim_cur(td, RLIMIT_FSIZE);
2433 * Is the limit reached?
2435 if (__predict_true((uoff_t)uio->uio_offset + uio->uio_resid <= lim))
2439 * Prepared filesystems can handle writes truncated to the
2442 if (adj && (uoff_t)uio->uio_offset < lim) {
2443 uio->uio_resid = lim - (uoff_t)uio->uio_offset;
2447 if (!ktr_write || ktr_filesize_limit_signal)
2448 vn_send_sigxfsz(td->td_proc);
2453 * Helper for VOP_WRITE() implementations, the common code to
2454 * handle maximum supported file size on the filesystem, and
2455 * RLIMIT_FSIZE, except for special writes from accounting subsystem
2458 * For maximum file size (maxfsz argument):
2459 * - return EFBIG if uio_offset is beyond it
2460 * - otherwise, clamp uio_resid if write would extend file beyond maxfsz.
2463 * - return EFBIG and send SIGXFSZ if uio_offset is beyond the limit
2464 * - otherwise, clamp uio_resid if write would extend file beyond limit.
2466 * If clamping occured, the adjustment for uio_resid is stored in
2467 * *resid_adj, to be re-applied by vn_rlimit_fsizex_res() on return
2471 vn_rlimit_fsizex(const struct vnode *vp, struct uio *uio, off_t maxfsz,
2472 ssize_t *resid_adj, struct thread *td)
2478 resid_orig = uio->uio_resid;
2479 adj = resid_adj != NULL;
2480 error = vn_rlimit_fsizex1(vp, uio, maxfsz, adj, td);
2482 *resid_adj = resid_orig - uio->uio_resid;
2487 vn_rlimit_fsizex_res(struct uio *uio, ssize_t resid_adj)
2489 uio->uio_resid += resid_adj;
2493 vn_rlimit_fsize(const struct vnode *vp, const struct uio *uio,
2496 return (vn_rlimit_fsizex(vp, __DECONST(struct uio *, uio), 0, NULL,
2501 vn_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
2508 vn_lock(vp, LK_SHARED | LK_RETRY);
2509 AUDIT_ARG_VNODE1(vp);
2512 return (setfmode(td, active_cred, vp, mode));
2516 vn_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
2523 vn_lock(vp, LK_SHARED | LK_RETRY);
2524 AUDIT_ARG_VNODE1(vp);
2527 return (setfown(td, active_cred, vp, uid, gid));
2531 * Remove pages in the range ["start", "end") from the vnode's VM object. If
2532 * "end" is 0, then the range extends to the end of the object.
2535 vn_pages_remove(struct vnode *vp, vm_pindex_t start, vm_pindex_t end)
2539 if ((object = vp->v_object) == NULL)
2541 VM_OBJECT_WLOCK(object);
2542 vm_object_page_remove(object, start, end, 0);
2543 VM_OBJECT_WUNLOCK(object);
2547 * Like vn_pages_remove(), but skips invalid pages, which by definition are not
2548 * mapped into any process' address space. Filesystems may use this in
2549 * preference to vn_pages_remove() to avoid blocking on pages busied in
2550 * preparation for a VOP_GETPAGES.
2553 vn_pages_remove_valid(struct vnode *vp, vm_pindex_t start, vm_pindex_t end)
2557 if ((object = vp->v_object) == NULL)
2559 VM_OBJECT_WLOCK(object);
2560 vm_object_page_remove(object, start, end, OBJPR_VALIDONLY);
2561 VM_OBJECT_WUNLOCK(object);
2565 vn_bmap_seekhole_locked(struct vnode *vp, u_long cmd, off_t *off,
2575 KASSERT(cmd == FIOSEEKHOLE || cmd == FIOSEEKDATA,
2576 ("%s: Wrong command %lu", __func__, cmd));
2577 ASSERT_VOP_ELOCKED(vp, "vn_bmap_seekhole_locked");
2579 if (vp->v_type != VREG) {
2583 error = vn_getsize_locked(vp, &size, cred);
2587 if (noff < 0 || noff >= size) {
2592 /* See the comment in ufs_bmap_seekdata(). */
2595 VM_OBJECT_WLOCK(obj);
2596 vm_object_page_clean(obj, 0, 0, OBJPC_SYNC);
2597 VM_OBJECT_WUNLOCK(obj);
2600 bsize = vp->v_mount->mnt_stat.f_iosize;
2601 for (bn = noff / bsize; noff < size; bn++, noff += bsize -
2603 error = VOP_BMAP(vp, bn, NULL, &bnp, NULL, NULL);
2604 if (error == EOPNOTSUPP) {
2608 if ((bnp == -1 && cmd == FIOSEEKHOLE) ||
2609 (bnp != -1 && cmd == FIOSEEKDATA)) {
2618 /* noff == size. There is an implicit hole at the end of file. */
2619 if (cmd == FIOSEEKDATA)
2628 vn_bmap_seekhole(struct vnode *vp, u_long cmd, off_t *off, struct ucred *cred)
2632 KASSERT(cmd == FIOSEEKHOLE || cmd == FIOSEEKDATA,
2633 ("%s: Wrong command %lu", __func__, cmd));
2635 if (vn_lock(vp, LK_EXCLUSIVE) != 0)
2637 error = vn_bmap_seekhole_locked(vp, cmd, off, cred);
2643 vn_seek(struct file *fp, off_t offset, int whence, struct thread *td)
2647 off_t foffset, fsize, size;
2650 cred = td->td_ucred;
2652 foffset = foffset_lock(fp, 0);
2653 noneg = (vp->v_type != VCHR);
2659 (offset > 0 && foffset > OFF_MAX - offset))) {
2666 error = vn_getsize(vp, &fsize, cred);
2671 * If the file references a disk device, then fetch
2672 * the media size and use that to determine the ending
2675 if (fsize == 0 && vp->v_type == VCHR &&
2676 fo_ioctl(fp, DIOCGMEDIASIZE, &size, cred, td) == 0)
2678 if (noneg && offset > 0 && fsize > OFF_MAX - offset) {
2687 error = fo_ioctl(fp, FIOSEEKDATA, &offset, cred, td);
2688 if (error == ENOTTY)
2692 error = fo_ioctl(fp, FIOSEEKHOLE, &offset, cred, td);
2693 if (error == ENOTTY)
2699 if (error == 0 && noneg && offset < 0)
2703 VFS_KNOTE_UNLOCKED(vp, 0);
2704 td->td_uretoff.tdu_off = offset;
2706 foffset_unlock(fp, offset, error != 0 ? FOF_NOUPDATE : 0);
2711 vn_utimes_perm(struct vnode *vp, struct vattr *vap, struct ucred *cred,
2717 * Grant permission if the caller is the owner of the file, or
2718 * the super-user, or has ACL_WRITE_ATTRIBUTES permission on
2719 * on the file. If the time pointer is null, then write
2720 * permission on the file is also sufficient.
2722 * From NFSv4.1, draft 21, 6.2.1.3.1, Discussion of Mask Attributes:
2723 * A user having ACL_WRITE_DATA or ACL_WRITE_ATTRIBUTES
2724 * will be allowed to set the times [..] to the current
2727 error = VOP_ACCESSX(vp, VWRITE_ATTRIBUTES, cred, td);
2728 if (error != 0 && (vap->va_vaflags & VA_UTIMES_NULL) != 0)
2729 error = VOP_ACCESS(vp, VWRITE, cred, td);
2734 vn_fill_kinfo(struct file *fp, struct kinfo_file *kif, struct filedesc *fdp)
2739 if (fp->f_type == DTYPE_FIFO)
2740 kif->kf_type = KF_TYPE_FIFO;
2742 kif->kf_type = KF_TYPE_VNODE;
2745 FILEDESC_SUNLOCK(fdp);
2746 error = vn_fill_kinfo_vnode(vp, kif);
2748 FILEDESC_SLOCK(fdp);
2753 vn_fill_junk(struct kinfo_file *kif)
2758 * Simulate vn_fullpath returning changing values for a given
2759 * vp during e.g. coredump.
2761 len = (arc4random() % (sizeof(kif->kf_path) - 2)) + 1;
2762 olen = strlen(kif->kf_path);
2764 strcpy(&kif->kf_path[len - 1], "$");
2766 for (; olen < len; olen++)
2767 strcpy(&kif->kf_path[olen], "A");
2771 vn_fill_kinfo_vnode(struct vnode *vp, struct kinfo_file *kif)
2774 char *fullpath, *freepath;
2777 kif->kf_un.kf_file.kf_file_type = vntype_to_kinfo(vp->v_type);
2780 error = vn_fullpath(vp, &fullpath, &freepath);
2782 strlcpy(kif->kf_path, fullpath, sizeof(kif->kf_path));
2784 if (freepath != NULL)
2785 free(freepath, M_TEMP);
2787 KFAIL_POINT_CODE(DEBUG_FP, fill_kinfo_vnode__random_path,
2792 * Retrieve vnode attributes.
2794 va.va_fsid = VNOVAL;
2796 vn_lock(vp, LK_SHARED | LK_RETRY);
2797 error = VOP_GETATTR(vp, &va, curthread->td_ucred);
2801 if (va.va_fsid != VNOVAL)
2802 kif->kf_un.kf_file.kf_file_fsid = va.va_fsid;
2804 kif->kf_un.kf_file.kf_file_fsid =
2805 vp->v_mount->mnt_stat.f_fsid.val[0];
2806 kif->kf_un.kf_file.kf_file_fsid_freebsd11 =
2807 kif->kf_un.kf_file.kf_file_fsid; /* truncate */
2808 kif->kf_un.kf_file.kf_file_fileid = va.va_fileid;
2809 kif->kf_un.kf_file.kf_file_mode = MAKEIMODE(va.va_type, va.va_mode);
2810 kif->kf_un.kf_file.kf_file_size = va.va_size;
2811 kif->kf_un.kf_file.kf_file_rdev = va.va_rdev;
2812 kif->kf_un.kf_file.kf_file_rdev_freebsd11 =
2813 kif->kf_un.kf_file.kf_file_rdev; /* truncate */
2814 kif->kf_un.kf_file.kf_file_nlink = va.va_nlink;
2819 vn_mmap(struct file *fp, vm_map_t map, vm_offset_t *addr, vm_size_t size,
2820 vm_prot_t prot, vm_prot_t cap_maxprot, int flags, vm_ooffset_t foff,
2824 struct pmckern_map_in pkm;
2830 boolean_t writecounted;
2833 #if defined(COMPAT_FREEBSD7) || defined(COMPAT_FREEBSD6) || \
2834 defined(COMPAT_FREEBSD5) || defined(COMPAT_FREEBSD4)
2836 * POSIX shared-memory objects are defined to have
2837 * kernel persistence, and are not defined to support
2838 * read(2)/write(2) -- or even open(2). Thus, we can
2839 * use MAP_ASYNC to trade on-disk coherence for speed.
2840 * The shm_open(3) library routine turns on the FPOSIXSHM
2841 * flag to request this behavior.
2843 if ((fp->f_flag & FPOSIXSHM) != 0)
2844 flags |= MAP_NOSYNC;
2849 * Ensure that file and memory protections are
2850 * compatible. Note that we only worry about
2851 * writability if mapping is shared; in this case,
2852 * current and max prot are dictated by the open file.
2853 * XXX use the vnode instead? Problem is: what
2854 * credentials do we use for determination? What if
2855 * proc does a setuid?
2858 if (mp != NULL && (mp->mnt_flag & MNT_NOEXEC) != 0) {
2859 maxprot = VM_PROT_NONE;
2860 if ((prot & VM_PROT_EXECUTE) != 0)
2863 maxprot = VM_PROT_EXECUTE;
2864 if ((fp->f_flag & FREAD) != 0)
2865 maxprot |= VM_PROT_READ;
2866 else if ((prot & VM_PROT_READ) != 0)
2870 * If we are sharing potential changes via MAP_SHARED and we
2871 * are trying to get write permission although we opened it
2872 * without asking for it, bail out.
2874 if ((flags & MAP_SHARED) != 0) {
2875 if ((fp->f_flag & FWRITE) != 0)
2876 maxprot |= VM_PROT_WRITE;
2877 else if ((prot & VM_PROT_WRITE) != 0)
2880 maxprot |= VM_PROT_WRITE;
2881 cap_maxprot |= VM_PROT_WRITE;
2883 maxprot &= cap_maxprot;
2886 * For regular files and shared memory, POSIX requires that
2887 * the value of foff be a legitimate offset within the data
2888 * object. In particular, negative offsets are invalid.
2889 * Blocking negative offsets and overflows here avoids
2890 * possible wraparound or user-level access into reserved
2891 * ranges of the data object later. In contrast, POSIX does
2892 * not dictate how offsets are used by device drivers, so in
2893 * the case of a device mapping a negative offset is passed
2900 foff > OFF_MAX - size)
2903 writecounted = FALSE;
2904 error = vm_mmap_vnode(td, size, prot, &maxprot, &flags, vp,
2905 &foff, &object, &writecounted);
2908 error = vm_mmap_object(map, addr, size, prot, maxprot, flags, object,
2909 foff, writecounted, td);
2912 * If this mapping was accounted for in the vnode's
2913 * writecount, then undo that now.
2916 vm_pager_release_writecount(object, 0, size);
2917 vm_object_deallocate(object);
2920 /* Inform hwpmc(4) if an executable is being mapped. */
2921 if (PMC_HOOK_INSTALLED(PMC_FN_MMAP)) {
2922 if ((prot & VM_PROT_EXECUTE) != 0 && error == 0) {
2924 pkm.pm_address = (uintptr_t) *addr;
2925 PMC_CALL_HOOK_UNLOCKED(td, PMC_FN_MMAP, (void *) &pkm);
2933 vn_fsid(struct vnode *vp, struct vattr *va)
2937 f = &vp->v_mount->mnt_stat.f_fsid;
2938 va->va_fsid = (uint32_t)f->val[1];
2939 va->va_fsid <<= sizeof(f->val[1]) * NBBY;
2940 va->va_fsid += (uint32_t)f->val[0];
2944 vn_fsync_buf(struct vnode *vp, int waitfor)
2946 struct buf *bp, *nbp;
2949 int error, maxretry;
2952 maxretry = 10000; /* large, arbitrarily chosen */
2954 if (vp->v_type == VCHR) {
2956 mp = vp->v_rdev->si_mountpt;
2963 * MARK/SCAN initialization to avoid infinite loops.
2965 TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs) {
2966 bp->b_vflags &= ~BV_SCANNED;
2971 * Flush all dirty buffers associated with a vnode.
2974 TAILQ_FOREACH_SAFE(bp, &bo->bo_dirty.bv_hd, b_bobufs, nbp) {
2975 if ((bp->b_vflags & BV_SCANNED) != 0)
2977 bp->b_vflags |= BV_SCANNED;
2978 if (BUF_LOCK(bp, LK_EXCLUSIVE | LK_NOWAIT, NULL)) {
2979 if (waitfor != MNT_WAIT)
2982 LK_EXCLUSIVE | LK_INTERLOCK | LK_SLEEPFAIL,
2983 BO_LOCKPTR(bo)) != 0) {
2990 KASSERT(bp->b_bufobj == bo,
2991 ("bp %p wrong b_bufobj %p should be %p",
2992 bp, bp->b_bufobj, bo));
2993 if ((bp->b_flags & B_DELWRI) == 0)
2994 panic("fsync: not dirty");
2995 if ((vp->v_object != NULL) && (bp->b_flags & B_CLUSTEROK)) {
3001 if (maxretry < 1000)
3002 pause("dirty", hz < 1000 ? 1 : hz / 1000);
3008 * If synchronous the caller expects us to completely resolve all
3009 * dirty buffers in the system. Wait for in-progress I/O to
3010 * complete (which could include background bitmap writes), then
3011 * retry if dirty blocks still exist.
3013 if (waitfor == MNT_WAIT) {
3014 bufobj_wwait(bo, 0, 0);
3015 if (bo->bo_dirty.bv_cnt > 0) {
3017 * If we are unable to write any of these buffers
3018 * then we fail now rather than trying endlessly
3019 * to write them out.
3021 TAILQ_FOREACH(bp, &bo->bo_dirty.bv_hd, b_bobufs)
3022 if ((error = bp->b_error) != 0)
3024 if ((mp != NULL && mp->mnt_secondary_writes > 0) ||
3025 (error == 0 && --maxretry >= 0))
3033 vn_printf(vp, "fsync: giving up on dirty (error = %d) ", error);
3039 * Copies a byte range from invp to outvp. Calls VOP_COPY_FILE_RANGE()
3040 * or vn_generic_copy_file_range() after rangelocking the byte ranges,
3041 * to do the actual copy.
3042 * vn_generic_copy_file_range() is factored out, so it can be called
3043 * from a VOP_COPY_FILE_RANGE() call as well, but handles vnodes from
3044 * different file systems.
3047 vn_copy_file_range(struct vnode *invp, off_t *inoffp, struct vnode *outvp,
3048 off_t *outoffp, size_t *lenp, unsigned int flags, struct ucred *incred,
3049 struct ucred *outcred, struct thread *fsize_td)
3056 *lenp = 0; /* For error returns. */
3059 /* Do some sanity checks on the arguments. */
3060 if (invp->v_type == VDIR || outvp->v_type == VDIR)
3062 else if (*inoffp < 0 || *outoffp < 0 ||
3063 invp->v_type != VREG || outvp->v_type != VREG)
3068 /* Ensure offset + len does not wrap around. */
3071 if (uval > INT64_MAX)
3072 len = INT64_MAX - *inoffp;
3075 if (uval > INT64_MAX)
3076 len = INT64_MAX - *outoffp;
3081 * If the two vnode are for the same file system, call
3082 * VOP_COPY_FILE_RANGE(), otherwise call vn_generic_copy_file_range()
3083 * which can handle copies across multiple file systems.
3086 if (invp->v_mount == outvp->v_mount)
3087 error = VOP_COPY_FILE_RANGE(invp, inoffp, outvp, outoffp,
3088 lenp, flags, incred, outcred, fsize_td);
3090 error = vn_generic_copy_file_range(invp, inoffp, outvp,
3091 outoffp, lenp, flags, incred, outcred, fsize_td);
3097 * Test len bytes of data starting at dat for all bytes == 0.
3098 * Return true if all bytes are zero, false otherwise.
3099 * Expects dat to be well aligned.
3102 mem_iszero(void *dat, int len)
3108 for (p = dat; len > 0; len -= sizeof(*p), p++) {
3109 if (len >= sizeof(*p)) {
3113 cp = (const char *)p;
3114 for (i = 0; i < len; i++, cp++)
3123 * Look for a hole in the output file and, if found, adjust *outoffp
3124 * and *xferp to skip past the hole.
3125 * *xferp is the entire hole length to be written and xfer2 is how many bytes
3126 * to be written as 0's upon return.
3129 vn_skip_hole(struct vnode *outvp, off_t xfer2, off_t *outoffp, off_t *xferp,
3130 off_t *dataoffp, off_t *holeoffp, struct ucred *cred)
3135 if (*holeoffp == 0 || *holeoffp <= *outoffp) {
3136 *dataoffp = *outoffp;
3137 error = VOP_IOCTL(outvp, FIOSEEKDATA, dataoffp, 0, cred,
3140 *holeoffp = *dataoffp;
3141 error = VOP_IOCTL(outvp, FIOSEEKHOLE, holeoffp, 0, cred,
3144 if (error != 0 || *holeoffp == *dataoffp) {
3146 * Since outvp is unlocked, it may be possible for
3147 * another thread to do a truncate(), lseek(), write()
3148 * creating a hole at startoff between the above
3149 * VOP_IOCTL() calls, if the other thread does not do
3151 * If that happens, *holeoffp == *dataoffp and finding
3152 * the hole has failed, so disable vn_skip_hole().
3154 *holeoffp = -1; /* Disable use of vn_skip_hole(). */
3157 KASSERT(*dataoffp >= *outoffp,
3158 ("vn_skip_hole: dataoff=%jd < outoff=%jd",
3159 (intmax_t)*dataoffp, (intmax_t)*outoffp));
3160 KASSERT(*holeoffp > *dataoffp,
3161 ("vn_skip_hole: holeoff=%jd <= dataoff=%jd",
3162 (intmax_t)*holeoffp, (intmax_t)*dataoffp));
3166 * If there is a hole before the data starts, advance *outoffp and
3167 * *xferp past the hole.
3169 if (*dataoffp > *outoffp) {
3170 delta = *dataoffp - *outoffp;
3171 if (delta >= *xferp) {
3172 /* Entire *xferp is a hole. */
3179 xfer2 = MIN(xfer2, *xferp);
3183 * If a hole starts before the end of this xfer2, reduce this xfer2 so
3184 * that the write ends at the start of the hole.
3185 * *holeoffp should always be greater than *outoffp, but for the
3186 * non-INVARIANTS case, check this to make sure xfer2 remains a sane
3189 if (*holeoffp > *outoffp && *holeoffp < *outoffp + xfer2)
3190 xfer2 = *holeoffp - *outoffp;
3195 * Write an xfer sized chunk to outvp in blksize blocks from dat.
3196 * dat is a maximum of blksize in length and can be written repeatedly in
3198 * If growfile == true, just grow the file via vn_truncate_locked() instead
3199 * of doing actual writes.
3200 * If checkhole == true, a hole is being punched, so skip over any hole
3201 * already in the output file.
3204 vn_write_outvp(struct vnode *outvp, char *dat, off_t outoff, off_t xfer,
3205 u_long blksize, bool growfile, bool checkhole, struct ucred *cred)
3208 off_t dataoff, holeoff, xfer2;
3212 * Loop around doing writes of blksize until write has been completed.
3213 * Lock/unlock on each loop iteration so that a bwillwrite() can be
3214 * done for each iteration, since the xfer argument can be very
3215 * large if there is a large hole to punch in the output file.
3220 xfer2 = MIN(xfer, blksize);
3223 * Punching a hole. Skip writing if there is
3224 * already a hole in the output file.
3226 xfer2 = vn_skip_hole(outvp, xfer2, &outoff, &xfer,
3227 &dataoff, &holeoff, cred);
3232 KASSERT(xfer2 > 0, ("vn_write_outvp: xfer2=%jd",
3237 error = vn_start_write(outvp, &mp, V_WAIT);
3241 error = vn_lock(outvp, LK_EXCLUSIVE);
3243 error = vn_truncate_locked(outvp, outoff + xfer,
3248 error = vn_lock(outvp, vn_lktype_write(mp, outvp));
3250 error = vn_rdwr(UIO_WRITE, outvp, dat, xfer2,
3251 outoff, UIO_SYSSPACE, IO_NODELOCKED,
3252 curthread->td_ucred, cred, NULL, curthread);
3259 vn_finished_write(mp);
3260 } while (!growfile && xfer > 0 && error == 0);
3265 * Copy a byte range of one file to another. This function can handle the
3266 * case where invp and outvp are on different file systems.
3267 * It can also be called by a VOP_COPY_FILE_RANGE() to do the work, if there
3268 * is no better file system specific way to do it.
3271 vn_generic_copy_file_range(struct vnode *invp, off_t *inoffp,
3272 struct vnode *outvp, off_t *outoffp, size_t *lenp, unsigned int flags,
3273 struct ucred *incred, struct ucred *outcred, struct thread *fsize_td)
3276 off_t startoff, endoff, xfer, xfer2;
3278 int error, interrupted;
3279 bool cantseek, readzeros, eof, lastblock, holetoeof;
3280 ssize_t aresid, r = 0;
3281 size_t copylen, len, savlen;
3282 off_t insize, outsize;
3284 long holein, holeout;
3285 struct timespec curts, endts;
3287 holein = holeout = 0;
3288 savlen = len = *lenp;
3293 error = vn_lock(invp, LK_SHARED);
3296 if (VOP_PATHCONF(invp, _PC_MIN_HOLE_SIZE, &holein) != 0)
3299 error = vn_getsize_locked(invp, &insize, incred);
3305 error = vn_start_write(outvp, &mp, V_WAIT);
3307 error = vn_lock(outvp, LK_EXCLUSIVE);
3310 * If fsize_td != NULL, do a vn_rlimit_fsizex() call,
3311 * now that outvp is locked.
3313 if (fsize_td != NULL) {
3316 io.uio_offset = *outoffp;
3318 error = vn_rlimit_fsizex(outvp, &io, 0, &r, fsize_td);
3319 len = savlen = io.uio_resid;
3321 * No need to call vn_rlimit_fsizex_res before return,
3322 * since the uio is local.
3325 if (VOP_PATHCONF(outvp, _PC_MIN_HOLE_SIZE, &holeout) != 0)
3328 * Holes that are past EOF do not need to be written as a block
3329 * of zero bytes. So, truncate the output file as far as
3330 * possible and then use size to decide if writing 0
3331 * bytes is necessary in the loop below.
3334 error = vn_getsize_locked(outvp, &outsize, outcred);
3335 if (error == 0 && outsize > *outoffp && outsize <= *outoffp + len) {
3337 error = mac_vnode_check_write(curthread->td_ucred,
3341 error = vn_truncate_locked(outvp, *outoffp,
3349 vn_finished_write(mp);
3353 if (holein == 0 && holeout > 0) {
3355 * For this special case, the input data will be scanned
3356 * for blocks of all 0 bytes. For these blocks, the
3357 * write can be skipped for the output file to create
3358 * an unallocated region.
3359 * Therefore, use the appropriate size for the output file.
3362 if (blksize <= 512) {
3364 * Use f_iosize, since ZFS reports a _PC_MIN_HOLE_SIZE
3365 * of 512, although it actually only creates
3366 * unallocated regions for blocks >= f_iosize.
3368 blksize = outvp->v_mount->mnt_stat.f_iosize;
3372 * Use the larger of the two f_iosize values. If they are
3373 * not the same size, one will normally be an exact multiple of
3374 * the other, since they are both likely to be a power of 2.
3376 blksize = MAX(invp->v_mount->mnt_stat.f_iosize,
3377 outvp->v_mount->mnt_stat.f_iosize);
3380 /* Clip to sane limits. */
3383 else if (blksize > maxphys)
3385 dat = malloc(blksize, M_TEMP, M_WAITOK);
3388 * If VOP_IOCTL(FIOSEEKHOLE) works for invp, use it and FIOSEEKDATA
3389 * to find holes. Otherwise, just scan the read block for all 0s
3390 * in the inner loop where the data copying is done.
3391 * Note that some file systems such as NFSv3, NFSv4.0 and NFSv4.1 may
3392 * support holes on the server, but do not support FIOSEEKHOLE.
3393 * The kernel flag COPY_FILE_RANGE_TIMEO1SEC is used to indicate
3394 * that this function should return after 1second with a partial
3397 if ((flags & COPY_FILE_RANGE_TIMEO1SEC) != 0) {
3398 getnanouptime(&endts);
3401 timespecclear(&endts);
3402 holetoeof = eof = false;
3403 while (len > 0 && error == 0 && !eof && interrupted == 0) {
3404 endoff = 0; /* To shut up compilers. */
3410 * Find the next data area. If there is just a hole to EOF,
3411 * FIOSEEKDATA should fail with ENXIO.
3412 * (I do not know if any file system will report a hole to
3413 * EOF via FIOSEEKHOLE, but I am pretty sure FIOSEEKDATA
3414 * will fail for those file systems.)
3416 * For input files that don't support FIOSEEKDATA/FIOSEEKHOLE,
3417 * the code just falls through to the inner copy loop.
3421 error = VOP_IOCTL(invp, FIOSEEKDATA, &startoff, 0,
3423 if (error == ENXIO) {
3424 startoff = endoff = insize;
3425 eof = holetoeof = true;
3429 if (error == 0 && !holetoeof) {
3431 error = VOP_IOCTL(invp, FIOSEEKHOLE, &endoff, 0,
3434 * Since invp is unlocked, it may be possible for
3435 * another thread to do a truncate(), lseek(), write()
3436 * creating a hole at startoff between the above
3437 * VOP_IOCTL() calls, if the other thread does not do
3439 * If that happens, startoff == endoff and finding
3440 * the hole has failed, so set an error.
3442 if (error == 0 && startoff == endoff)
3443 error = EINVAL; /* Any error. Reset to 0. */
3446 if (startoff > *inoffp) {
3447 /* Found hole before data block. */
3448 xfer = MIN(startoff - *inoffp, len);
3449 if (*outoffp < outsize) {
3450 /* Must write 0s to punch hole. */
3451 xfer2 = MIN(outsize - *outoffp,
3453 memset(dat, 0, MIN(xfer2, blksize));
3454 error = vn_write_outvp(outvp, dat,
3455 *outoffp, xfer2, blksize, false,
3456 holeout > 0, outcred);
3459 if (error == 0 && *outoffp + xfer >
3460 outsize && (xfer == len || holetoeof)) {
3461 /* Grow output file (hole at end). */
3462 error = vn_write_outvp(outvp, dat,
3463 *outoffp, xfer, blksize, true,
3471 interrupted = sig_intr();
3472 if (timespecisset(&endts) &&
3474 getnanouptime(&curts);
3475 if (timespeccmp(&curts,
3483 copylen = MIN(len, endoff - startoff);
3495 * Set first xfer to end at a block boundary, so that
3496 * holes are more likely detected in the loop below via
3497 * the for all bytes 0 method.
3499 xfer -= (*inoffp % blksize);
3501 /* Loop copying the data block. */
3502 while (copylen > 0 && error == 0 && !eof && interrupted == 0) {
3505 error = vn_lock(invp, LK_SHARED);
3508 error = vn_rdwr(UIO_READ, invp, dat, xfer,
3509 startoff, UIO_SYSSPACE, IO_NODELOCKED,
3510 curthread->td_ucred, incred, &aresid,
3514 if (error == 0 && aresid > 0) {
3515 /* Stop the copy at EOF on the input file. */
3522 * Skip the write for holes past the initial EOF
3523 * of the output file, unless this is the last
3524 * write of the output file at EOF.
3526 readzeros = cantseek ? mem_iszero(dat, xfer) :
3530 if (!cantseek || *outoffp < outsize ||
3531 lastblock || !readzeros)
3532 error = vn_write_outvp(outvp, dat,
3533 *outoffp, xfer, blksize,
3534 readzeros && lastblock &&
3535 *outoffp >= outsize, false,
3544 interrupted = sig_intr();
3545 if (timespecisset(&endts) &&
3547 getnanouptime(&curts);
3548 if (timespeccmp(&curts,
3560 *lenp = savlen - len;
3566 vn_fallocate(struct file *fp, off_t offset, off_t len, struct thread *td)
3570 off_t olen, ooffset;
3573 int audited_vnode1 = 0;
3577 if (vp->v_type != VREG)
3580 /* Allocating blocks may take a long time, so iterate. */
3587 error = vn_start_write(vp, &mp, V_WAIT | V_PCATCH);
3590 error = vn_lock(vp, LK_EXCLUSIVE);
3592 vn_finished_write(mp);
3596 if (!audited_vnode1) {
3597 AUDIT_ARG_VNODE1(vp);
3602 error = mac_vnode_check_write(td->td_ucred, fp->f_cred, vp);
3605 error = VOP_ALLOCATE(vp, &offset, &len, 0,
3608 vn_finished_write(mp);
3610 if (olen + ooffset != offset + len) {
3611 panic("offset + len changed from %jx/%jx to %jx/%jx",
3612 ooffset, olen, offset, len);
3614 if (error != 0 || len == 0)
3616 KASSERT(olen > len, ("Iteration did not make progress?"));
3624 vn_deallocate_impl(struct vnode *vp, off_t *offset, off_t *length, int flags,
3625 int ioflag, struct ucred *cred, struct ucred *active_cred,
3626 struct ucred *file_cred)
3633 bool audited_vnode1 = false;
3642 if ((ioflag & (IO_NODELOCKED | IO_RANGELOCKED)) == 0)
3643 rl_cookie = vn_rangelock_wlock(vp, off, off + len);
3644 while (len > 0 && error == 0) {
3646 * Try to deallocate the longest range in one pass.
3647 * In case a pass takes too long to be executed, it returns
3648 * partial result. The residue will be proceeded in the next
3652 if ((ioflag & IO_NODELOCKED) == 0) {
3654 if ((error = vn_start_write(vp, &mp,
3655 V_WAIT | V_PCATCH)) != 0)
3657 vn_lock(vp, vn_lktype_write(mp, vp) | LK_RETRY);
3660 if (!audited_vnode1) {
3661 AUDIT_ARG_VNODE1(vp);
3662 audited_vnode1 = true;
3667 if ((ioflag & IO_NOMACCHECK) == 0)
3668 error = mac_vnode_check_write(active_cred, file_cred,
3672 error = VOP_DEALLOCATE(vp, &off, &len, flags, ioflag,
3675 if ((ioflag & IO_NODELOCKED) == 0) {
3678 vn_finished_write(mp);
3682 if (error == 0 && len != 0)
3686 if (rl_cookie != NULL)
3687 vn_rangelock_unlock(vp, rl_cookie);
3694 * This function is supposed to be used in the situations where the deallocation
3695 * is not triggered by a user request.
3698 vn_deallocate(struct vnode *vp, off_t *offset, off_t *length, int flags,
3699 int ioflag, struct ucred *active_cred, struct ucred *file_cred)
3703 if (*offset < 0 || *length <= 0 || *length > OFF_MAX - *offset ||
3706 if (vp->v_type != VREG)
3709 cred = file_cred != NOCRED ? file_cred : active_cred;
3710 return (vn_deallocate_impl(vp, offset, length, flags, ioflag, cred,
3711 active_cred, file_cred));
3715 vn_fspacectl(struct file *fp, int cmd, off_t *offset, off_t *length, int flags,
3716 struct ucred *active_cred, struct thread *td)
3722 KASSERT(cmd == SPACECTL_DEALLOC, ("vn_fspacectl: Invalid cmd"));
3723 KASSERT((flags & ~SPACECTL_F_SUPPORTED) == 0,
3724 ("vn_fspacectl: non-zero flags"));
3725 KASSERT(*offset >= 0 && *length > 0 && *length <= OFF_MAX - *offset,
3726 ("vn_fspacectl: offset/length overflow or underflow"));
3729 if (vp->v_type != VREG)
3732 ioflag = get_write_ioflag(fp);
3735 case SPACECTL_DEALLOC:
3736 error = vn_deallocate_impl(vp, offset, length, flags, ioflag,
3737 active_cred, active_cred, fp->f_cred);
3740 panic("vn_fspacectl: unknown cmd %d", cmd);
3747 * Keep this assert as long as sizeof(struct dirent) is used as the maximum
3750 _Static_assert(_GENERIC_MAXDIRSIZ == sizeof(struct dirent),
3751 "'struct dirent' size must be a multiple of its alignment "
3752 "(see _GENERIC_DIRLEN())");
3755 * Returns successive directory entries through some caller's provided buffer.
3757 * This function automatically refills the provided buffer with calls to
3758 * VOP_READDIR() (after MAC permission checks).
3760 * 'td' is used for credentials and passed to uiomove(). 'dirbuf' is the
3761 * caller's buffer to fill and 'dirbuflen' its allocated size. 'dirbuf' must
3762 * be properly aligned to access 'struct dirent' structures and 'dirbuflen'
3763 * must be greater than GENERIC_MAXDIRSIZ to avoid VOP_READDIR() returning
3764 * EINVAL (the latter is not a strong guarantee (yet); but EINVAL will always
3765 * be returned if this requirement is not verified). '*dpp' points to the
3766 * current directory entry in the buffer and '*len' contains the remaining
3767 * valid bytes in 'dirbuf' after 'dpp' (including the pointed entry).
3769 * At first call (or when restarting the read), '*len' must have been set to 0,
3770 * '*off' to 0 (or any valid start offset) and '*eofflag' to 0. There are no
3771 * more entries as soon as '*len' is 0 after a call that returned 0. Calling
3772 * again this function after such a condition is considered an error and EINVAL
3773 * will be returned. Other possible error codes are those of VOP_READDIR(),
3774 * EINTEGRITY if the returned entries do not pass coherency tests, or EINVAL
3775 * (bad call). All errors are unrecoverable, i.e., the state ('*len', '*off'
3776 * and '*eofflag') must be re-initialized before a subsequent call. On error
3777 * or at end of directory, '*dpp' is reset to NULL.
3779 * '*len', '*off' and '*eofflag' are internal state the caller should not
3780 * tamper with except as explained above. '*off' is the next directory offset
3781 * to read from to refill the buffer. '*eofflag' is set to 0 or 1 by the last
3782 * internal call to VOP_READDIR() that returned without error, indicating
3783 * whether it reached the end of the directory, and to 2 by this function after
3784 * all entries have been read.
3787 vn_dir_next_dirent(struct vnode *vp, struct thread *td,
3788 char *dirbuf, size_t dirbuflen,
3789 struct dirent **dpp, size_t *len, off_t *off, int *eofflag)
3791 struct dirent *dp = NULL;
3797 ASSERT_VOP_LOCKED(vp, "vnode not locked");
3798 VNASSERT(vp->v_type == VDIR, vp, ("vnode is not a directory"));
3799 MPASS2((uintptr_t)dirbuf < (uintptr_t)dirbuf + dirbuflen,
3800 "Address space overflow");
3802 if (__predict_false(dirbuflen < GENERIC_MAXDIRSIZ)) {
3803 /* Don't take any chances in this case */
3812 * The caller continued to call us after an error (we set dp to
3813 * NULL in a previous iteration). Bail out right now.
3815 if (__predict_false(dp == NULL))
3818 MPASS(*len <= dirbuflen);
3819 MPASS2((uintptr_t)dirbuf <= (uintptr_t)dp &&
3820 (uintptr_t)dp + *len <= (uintptr_t)dirbuf + dirbuflen,
3821 "Filled range not inside buffer");
3823 reclen = dp->d_reclen;
3824 if (reclen >= *len) {
3825 /* End of buffer reached */
3828 dp = (struct dirent *)((char *)dp + reclen);
3836 /* Have to refill. */
3842 /* Nothing more to read. */
3843 *eofflag = 2; /* Remember the caller reached EOF. */
3847 /* The caller didn't test for EOF. */
3852 iov.iov_base = dirbuf;
3853 iov.iov_len = dirbuflen;
3857 uio.uio_offset = *off;
3858 uio.uio_resid = dirbuflen;
3859 uio.uio_segflg = UIO_SYSSPACE;
3860 uio.uio_rw = UIO_READ;
3864 error = mac_vnode_check_readdir(td->td_ucred, vp);
3867 error = VOP_READDIR(vp, &uio, td->td_ucred, eofflag,
3872 *len = dirbuflen - uio.uio_resid;
3873 *off = uio.uio_offset;
3876 /* Sanity check on INVARIANTS. */
3877 MPASS(*eofflag != 0);
3883 * Normalize the flag returned by VOP_READDIR(), since we use 2
3884 * as a sentinel value.
3889 dp = (struct dirent *)dirbuf;
3892 if (__predict_false(*len < GENERIC_MINDIRSIZ ||
3893 dp->d_reclen < GENERIC_MINDIRSIZ)) {
3907 * Checks whether a directory is empty or not.
3909 * If the directory is empty, returns 0, and if it is not, ENOTEMPTY. Other
3910 * values are genuine errors preventing the check.
3913 vn_dir_check_empty(struct vnode *vp)
3915 struct thread *const td = curthread;
3917 size_t dirbuflen, len;
3923 ASSERT_VOP_LOCKED(vp, "vfs_emptydir");
3924 VNPASS(vp->v_type == VDIR, vp);
3926 error = VOP_GETATTR(vp, &va, td->td_ucred);
3930 dirbuflen = max(DEV_BSIZE, GENERIC_MAXDIRSIZ);
3931 if (dirbuflen < va.va_blocksize)
3932 dirbuflen = va.va_blocksize;
3933 dirbuf = malloc(dirbuflen, M_TEMP, M_WAITOK);
3940 error = vn_dir_next_dirent(vp, td, dirbuf, dirbuflen,
3941 &dp, &len, &off, &eofflag);
3952 * Skip whiteouts. Unionfs operates on filesystems only and
3953 * not on hierarchies, so these whiteouts would be shadowed on
3954 * the system hierarchy but not for a union using the
3955 * filesystem of their directories as the upper layer.
3956 * Additionally, unionfs currently transparently exposes
3957 * union-specific metadata of its upper layer, meaning that
3958 * whiteouts can be seen through the union view in empty
3959 * directories. Taking into account these whiteouts would then
3960 * prevent mounting another filesystem on such effectively
3961 * empty directories.
3963 if (dp->d_type == DT_WHT)
3967 * Any file in the directory which is not '.' or '..' indicates
3968 * the directory is not empty.
3970 switch (dp->d_namlen) {
3972 if (dp->d_name[1] != '.') {
3973 /* Can't be '..' (nor '.') */
3979 if (dp->d_name[0] != '.') {
3980 /* Can't be '..' nor '.' */
3993 free(dirbuf, M_TEMP);
3998 static u_long vn_lock_pair_pause_cnt;
3999 SYSCTL_ULONG(_debug, OID_AUTO, vn_lock_pair_pause, CTLFLAG_RD,
4000 &vn_lock_pair_pause_cnt, 0,
4001 "Count of vn_lock_pair deadlocks");
4003 u_int vn_lock_pair_pause_max;
4004 SYSCTL_UINT(_debug, OID_AUTO, vn_lock_pair_pause_max, CTLFLAG_RW,
4005 &vn_lock_pair_pause_max, 0,
4006 "Max ticks for vn_lock_pair deadlock avoidance sleep");
4009 vn_lock_pair_pause(const char *wmesg)
4011 atomic_add_long(&vn_lock_pair_pause_cnt, 1);
4012 pause(wmesg, prng32_bounded(vn_lock_pair_pause_max));
4016 * Lock pair of vnodes vp1, vp2, avoiding lock order reversal.
4017 * vp1_locked indicates whether vp1 is locked; if not, vp1 must be
4018 * unlocked. Same for vp2 and vp2_locked. One of the vnodes can be
4021 * The function returns with both vnodes exclusively or shared locked,
4022 * according to corresponding lkflags, and guarantees that it does not
4023 * create lock order reversal with other threads during its execution.
4024 * Both vnodes could be unlocked temporary (and reclaimed).
4026 * If requesting shared locking, locked vnode lock must not be recursed.
4028 * Only one of LK_SHARED and LK_EXCLUSIVE must be specified.
4029 * LK_NODDLKTREAT can be optionally passed.
4032 vn_lock_pair(struct vnode *vp1, bool vp1_locked, int lkflags1,
4033 struct vnode *vp2, bool vp2_locked, int lkflags2)
4037 MPASS(((lkflags1 & LK_SHARED) != 0) ^ ((lkflags1 & LK_EXCLUSIVE) != 0));
4038 MPASS((lkflags1 & ~(LK_SHARED | LK_EXCLUSIVE | LK_NODDLKTREAT)) == 0);
4039 MPASS(((lkflags2 & LK_SHARED) != 0) ^ ((lkflags2 & LK_EXCLUSIVE) != 0));
4040 MPASS((lkflags2 & ~(LK_SHARED | LK_EXCLUSIVE | LK_NODDLKTREAT)) == 0);
4042 if (vp1 == NULL && vp2 == NULL)
4046 if ((lkflags1 & LK_SHARED) != 0 &&
4047 (vp1->v_vnlock->lock_object.lo_flags & LK_NOSHARE) != 0)
4048 lkflags1 = (lkflags1 & ~LK_SHARED) | LK_EXCLUSIVE;
4049 if (vp1_locked && VOP_ISLOCKED(vp1) != LK_EXCLUSIVE) {
4050 ASSERT_VOP_LOCKED(vp1, "vp1");
4051 if ((lkflags1 & LK_EXCLUSIVE) != 0) {
4053 ASSERT_VOP_UNLOCKED(vp1,
4054 "vp1 shared recursed");
4057 } else if (!vp1_locked)
4058 ASSERT_VOP_UNLOCKED(vp1, "vp1");
4064 if ((lkflags2 & LK_SHARED) != 0 &&
4065 (vp2->v_vnlock->lock_object.lo_flags & LK_NOSHARE) != 0)
4066 lkflags2 = (lkflags2 & ~LK_SHARED) | LK_EXCLUSIVE;
4067 if (vp2_locked && VOP_ISLOCKED(vp2) != LK_EXCLUSIVE) {
4068 ASSERT_VOP_LOCKED(vp2, "vp2");
4069 if ((lkflags2 & LK_EXCLUSIVE) != 0) {
4071 ASSERT_VOP_UNLOCKED(vp2,
4072 "vp2 shared recursed");
4075 } else if (!vp2_locked)
4076 ASSERT_VOP_UNLOCKED(vp2, "vp2");
4081 if (!vp1_locked && !vp2_locked) {
4082 vn_lock(vp1, lkflags1 | LK_RETRY);
4086 while (!vp1_locked || !vp2_locked) {
4087 if (vp1_locked && vp2 != NULL) {
4089 error = VOP_LOCK1(vp2, lkflags2 | LK_NOWAIT,
4090 __FILE__, __LINE__);
4095 vn_lock_pair_pause("vlp1");
4097 vn_lock(vp2, lkflags2 | LK_RETRY);
4100 if (vp2_locked && vp1 != NULL) {
4102 error = VOP_LOCK1(vp1, lkflags1 | LK_NOWAIT,
4103 __FILE__, __LINE__);
4108 vn_lock_pair_pause("vlp2");
4110 vn_lock(vp1, lkflags1 | LK_RETRY);
4115 if (lkflags1 == LK_EXCLUSIVE)
4116 ASSERT_VOP_ELOCKED(vp1, "vp1 ret");
4118 ASSERT_VOP_LOCKED(vp1, "vp1 ret");
4121 if (lkflags2 == LK_EXCLUSIVE)
4122 ASSERT_VOP_ELOCKED(vp2, "vp2 ret");
4124 ASSERT_VOP_LOCKED(vp2, "vp2 ret");
4129 vn_lktype_write(struct mount *mp, struct vnode *vp)
4131 if (MNT_SHARED_WRITES(mp) ||
4132 (mp == NULL && MNT_SHARED_WRITES(vp->v_mount)))
4134 return (LK_EXCLUSIVE);