2 * Copyright (c) 1982, 1986, 1989, 1993
3 * The Regents of the University of California. All rights reserved.
4 * (c) UNIX System Laboratories, Inc.
5 * All or some portions of this file are derived from material licensed
6 * to the University of California by American Telephone and Telegraph
7 * Co. or Unix System Laboratories, Inc. and are reproduced herein with
8 * the permission of UNIX System Laboratories, Inc.
10 * Copyright (c) 2012 Konstantin Belousov <kib@FreeBSD.org>
11 * Copyright (c) 2013 The FreeBSD Foundation
13 * Portions of this software were developed by Konstantin Belousov
14 * under sponsorship from the FreeBSD Foundation.
16 * Redistribution and use in source and binary forms, with or without
17 * modification, are permitted provided that the following conditions
19 * 1. Redistributions of source code must retain the above copyright
20 * notice, this list of conditions and the following disclaimer.
21 * 2. Redistributions in binary form must reproduce the above copyright
22 * notice, this list of conditions and the following disclaimer in the
23 * documentation and/or other materials provided with the distribution.
24 * 4. Neither the name of the University nor the names of its contributors
25 * may be used to endorse or promote products derived from this software
26 * without specific prior written permission.
28 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
29 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
30 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
31 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
32 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
33 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
34 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
35 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
36 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
37 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
40 * @(#)vfs_vnops.c 8.2 (Berkeley) 1/21/94
43 #include <sys/cdefs.h>
44 __FBSDID("$FreeBSD$");
46 #include <sys/param.h>
47 #include <sys/systm.h>
48 #include <sys/fcntl.h>
54 #include <sys/limits.h>
56 #include <sys/mount.h>
57 #include <sys/mutex.h>
58 #include <sys/namei.h>
59 #include <sys/vnode.h>
62 #include <sys/filio.h>
63 #include <sys/resourcevar.h>
64 #include <sys/rwlock.h>
66 #include <sys/sysctl.h>
67 #include <sys/ttycom.h>
69 #include <sys/syslog.h>
70 #include <sys/unistd.h>
72 #include <security/audit/audit.h>
73 #include <security/mac/mac_framework.h>
76 #include <vm/vm_extern.h>
78 #include <vm/vm_map.h>
79 #include <vm/vm_object.h>
80 #include <vm/vm_page.h>
82 static fo_rdwr_t vn_read;
83 static fo_rdwr_t vn_write;
84 static fo_rdwr_t vn_io_fault;
85 static fo_truncate_t vn_truncate;
86 static fo_ioctl_t vn_ioctl;
87 static fo_poll_t vn_poll;
88 static fo_kqfilter_t vn_kqfilter;
89 static fo_stat_t vn_statfile;
90 static fo_close_t vn_closefile;
92 struct fileops vnops = {
93 .fo_read = vn_io_fault,
94 .fo_write = vn_io_fault,
95 .fo_truncate = vn_truncate,
98 .fo_kqfilter = vn_kqfilter,
99 .fo_stat = vn_statfile,
100 .fo_close = vn_closefile,
101 .fo_chmod = vn_chmod,
102 .fo_chown = vn_chown,
103 .fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE
107 vn_open(ndp, flagp, cmode, fp)
108 struct nameidata *ndp;
112 struct thread *td = ndp->ni_cnd.cn_thread;
114 return (vn_open_cred(ndp, flagp, cmode, 0, td->td_ucred, fp));
118 * Common code for vnode open operations via a name lookup.
119 * Lookup the vnode and invoke VOP_CREATE if needed.
120 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine.
122 * Note that this does NOT free nameidata for the successful case,
123 * due to the NDINIT being done elsewhere.
126 vn_open_cred(struct nameidata *ndp, int *flagp, int cmode, u_int vn_open_flags,
127 struct ucred *cred, struct file *fp)
131 struct thread *td = ndp->ni_cnd.cn_thread;
133 struct vattr *vap = &vat;
138 if (fmode & O_CREAT) {
139 ndp->ni_cnd.cn_nameiop = CREATE;
140 ndp->ni_cnd.cn_flags = ISOPEN | LOCKPARENT | LOCKLEAF;
141 if ((fmode & O_EXCL) == 0 && (fmode & O_NOFOLLOW) == 0)
142 ndp->ni_cnd.cn_flags |= FOLLOW;
143 if (!(vn_open_flags & VN_OPEN_NOAUDIT))
144 ndp->ni_cnd.cn_flags |= AUDITVNODE1;
145 if (vn_open_flags & VN_OPEN_NOCAPCHECK)
146 ndp->ni_cnd.cn_flags |= NOCAPCHECK;
148 if ((error = namei(ndp)) != 0)
150 if (ndp->ni_vp == NULL) {
153 vap->va_mode = cmode;
155 vap->va_vaflags |= VA_EXCLUSIVE;
156 if (vn_start_write(ndp->ni_dvp, &mp, V_NOWAIT) != 0) {
157 NDFREE(ndp, NDF_ONLY_PNBUF);
159 if ((error = vn_start_write(NULL, &mp,
160 V_XSLEEP | PCATCH)) != 0)
165 error = mac_vnode_check_create(cred, ndp->ni_dvp,
169 error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp,
172 vn_finished_write(mp);
174 NDFREE(ndp, NDF_ONLY_PNBUF);
180 if (ndp->ni_dvp == ndp->ni_vp)
186 if (fmode & O_EXCL) {
193 ndp->ni_cnd.cn_nameiop = LOOKUP;
194 ndp->ni_cnd.cn_flags = ISOPEN |
195 ((fmode & O_NOFOLLOW) ? NOFOLLOW : FOLLOW) | LOCKLEAF;
196 if (!(fmode & FWRITE))
197 ndp->ni_cnd.cn_flags |= LOCKSHARED;
198 if (!(vn_open_flags & VN_OPEN_NOAUDIT))
199 ndp->ni_cnd.cn_flags |= AUDITVNODE1;
200 if (vn_open_flags & VN_OPEN_NOCAPCHECK)
201 ndp->ni_cnd.cn_flags |= NOCAPCHECK;
202 if ((error = namei(ndp)) != 0)
206 error = vn_open_vnode(vp, fmode, cred, td, fp);
212 NDFREE(ndp, NDF_ONLY_PNBUF);
220 * Common code for vnode open operations once a vnode is located.
221 * Check permissions, and call the VOP_OPEN routine.
224 vn_open_vnode(struct vnode *vp, int fmode, struct ucred *cred,
225 struct thread *td, struct file *fp)
230 int error, have_flock, lock_flags, type;
232 if (vp->v_type == VLNK)
234 if (vp->v_type == VSOCK)
236 if (vp->v_type != VDIR && fmode & O_DIRECTORY)
239 if (fmode & (FWRITE | O_TRUNC)) {
240 if (vp->v_type == VDIR)
248 if ((fmode & O_APPEND) && (fmode & FWRITE))
251 error = mac_vnode_check_open(cred, vp, accmode);
255 if ((fmode & O_CREAT) == 0) {
256 if (accmode & VWRITE) {
257 error = vn_writechk(vp);
262 error = VOP_ACCESS(vp, accmode, cred, td);
267 if ((error = VOP_OPEN(vp, fmode, cred, td, fp)) != 0)
270 if (fmode & (O_EXLOCK | O_SHLOCK)) {
271 KASSERT(fp != NULL, ("open with flock requires fp"));
272 lock_flags = VOP_ISLOCKED(vp);
274 lf.l_whence = SEEK_SET;
277 if (fmode & O_EXLOCK)
282 if ((fmode & FNONBLOCK) == 0)
284 error = VOP_ADVLOCK(vp, (caddr_t)fp, F_SETLK, &lf, type);
285 have_flock = (error == 0);
286 vn_lock(vp, lock_flags | LK_RETRY);
287 if (error == 0 && vp->v_iflag & VI_DOOMED)
290 * Another thread might have used this vnode as an
291 * executable while the vnode lock was dropped.
292 * Ensure the vnode is still able to be opened for
293 * writing after the lock has been obtained.
295 if (error == 0 && accmode & VWRITE)
296 error = vn_writechk(vp);
300 lf.l_whence = SEEK_SET;
304 (void) VOP_ADVLOCK(vp, fp, F_UNLCK, &lf,
307 vn_start_write(vp, &mp, V_WAIT);
308 vn_lock(vp, lock_flags | LK_RETRY);
309 (void)VOP_CLOSE(vp, fmode, cred, td);
310 vn_finished_write(mp);
313 fp->f_flag |= FHASLOCK;
315 if (fmode & FWRITE) {
316 VOP_ADD_WRITECOUNT(vp, 1);
317 CTR3(KTR_VFS, "%s: vp %p v_writecount increased to %d",
318 __func__, vp, vp->v_writecount);
320 ASSERT_VOP_LOCKED(vp, "vn_open_vnode");
325 * Check for write permissions on the specified vnode.
326 * Prototype text segments cannot be written.
330 register struct vnode *vp;
333 ASSERT_VOP_LOCKED(vp, "vn_writechk");
335 * If there's shared text associated with
336 * the vnode, try to free it up once. If
337 * we fail, we can't allow writing.
349 vn_close(vp, flags, file_cred, td)
350 register struct vnode *vp;
352 struct ucred *file_cred;
356 int error, lock_flags;
358 if (!(flags & FWRITE) && vp->v_mount != NULL &&
359 vp->v_mount->mnt_kern_flag & MNTK_EXTENDED_SHARED)
360 lock_flags = LK_SHARED;
362 lock_flags = LK_EXCLUSIVE;
364 vn_start_write(vp, &mp, V_WAIT);
365 vn_lock(vp, lock_flags | LK_RETRY);
366 if (flags & FWRITE) {
367 VNASSERT(vp->v_writecount > 0, vp,
368 ("vn_close: negative writecount"));
369 VOP_ADD_WRITECOUNT(vp, -1);
370 CTR3(KTR_VFS, "%s: vp %p v_writecount decreased to %d",
371 __func__, vp, vp->v_writecount);
373 error = VOP_CLOSE(vp, flags, file_cred, td);
375 vn_finished_write(mp);
380 * Heuristic to detect sequential operation.
383 sequential_heuristic(struct uio *uio, struct file *fp)
386 if (atomic_load_acq_int(&(fp->f_flag)) & FRDAHEAD)
387 return (fp->f_seqcount << IO_SEQSHIFT);
390 * Offset 0 is handled specially. open() sets f_seqcount to 1 so
391 * that the first I/O is normally considered to be slightly
392 * sequential. Seeking to offset 0 doesn't change sequentiality
393 * unless previous seeks have reduced f_seqcount to 0, in which
394 * case offset 0 is not special.
396 if ((uio->uio_offset == 0 && fp->f_seqcount > 0) ||
397 uio->uio_offset == fp->f_nextoff) {
399 * f_seqcount is in units of fixed-size blocks so that it
400 * depends mainly on the amount of sequential I/O and not
401 * much on the number of sequential I/O's. The fixed size
402 * of 16384 is hard-coded here since it is (not quite) just
403 * a magic size that works well here. This size is more
404 * closely related to the best I/O size for real disks than
405 * to any block size used by software.
407 fp->f_seqcount += howmany(uio->uio_resid, 16384);
408 if (fp->f_seqcount > IO_SEQMAX)
409 fp->f_seqcount = IO_SEQMAX;
410 return (fp->f_seqcount << IO_SEQSHIFT);
413 /* Not sequential. Quickly draw-down sequentiality. */
414 if (fp->f_seqcount > 1)
422 * Package up an I/O request on a vnode into a uio and do it.
425 vn_rdwr(enum uio_rw rw, struct vnode *vp, void *base, int len, off_t offset,
426 enum uio_seg segflg, int ioflg, struct ucred *active_cred,
427 struct ucred *file_cred, ssize_t *aresid, struct thread *td)
434 int error, lock_flags;
436 auio.uio_iov = &aiov;
438 aiov.iov_base = base;
440 auio.uio_resid = len;
441 auio.uio_offset = offset;
442 auio.uio_segflg = segflg;
447 if ((ioflg & IO_NODELOCKED) == 0) {
448 if (rw == UIO_READ) {
449 rl_cookie = vn_rangelock_rlock(vp, offset,
452 rl_cookie = vn_rangelock_wlock(vp, offset,
456 if (rw == UIO_WRITE) {
457 if (vp->v_type != VCHR &&
458 (error = vn_start_write(vp, &mp, V_WAIT | PCATCH))
461 if (MNT_SHARED_WRITES(mp) ||
462 ((mp == NULL) && MNT_SHARED_WRITES(vp->v_mount)))
463 lock_flags = LK_SHARED;
465 lock_flags = LK_EXCLUSIVE;
467 lock_flags = LK_SHARED;
468 vn_lock(vp, lock_flags | LK_RETRY);
472 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
474 if ((ioflg & IO_NOMACCHECK) == 0) {
476 error = mac_vnode_check_read(active_cred, file_cred,
479 error = mac_vnode_check_write(active_cred, file_cred,
484 if (file_cred != NULL)
489 error = VOP_READ(vp, &auio, ioflg, cred);
491 error = VOP_WRITE(vp, &auio, ioflg, cred);
494 *aresid = auio.uio_resid;
496 if (auio.uio_resid && error == 0)
498 if ((ioflg & IO_NODELOCKED) == 0) {
501 vn_finished_write(mp);
504 if (rl_cookie != NULL)
505 vn_rangelock_unlock(vp, rl_cookie);
510 * Package up an I/O request on a vnode into a uio and do it. The I/O
511 * request is split up into smaller chunks and we try to avoid saturating
512 * the buffer cache while potentially holding a vnode locked, so we
513 * check bwillwrite() before calling vn_rdwr(). We also call kern_yield()
514 * to give other processes a chance to lock the vnode (either other processes
515 * core'ing the same binary, or unrelated processes scanning the directory).
518 vn_rdwr_inchunks(rw, vp, base, len, offset, segflg, ioflg, active_cred,
519 file_cred, aresid, td)
527 struct ucred *active_cred;
528 struct ucred *file_cred;
539 * Force `offset' to a multiple of MAXBSIZE except possibly
540 * for the first chunk, so that filesystems only need to
541 * write full blocks except possibly for the first and last
544 chunk = MAXBSIZE - (uoff_t)offset % MAXBSIZE;
548 if (rw != UIO_READ && vp->v_type == VREG)
551 error = vn_rdwr(rw, vp, base, chunk, offset, segflg,
552 ioflg, active_cred, file_cred, &iaresid, td);
553 len -= chunk; /* aresid calc already includes length */
557 base = (char *)base + chunk;
558 kern_yield(PRI_USER);
561 *aresid = len + iaresid;
566 foffset_lock(struct file *fp, int flags)
571 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
573 #if OFF_MAX <= LONG_MAX
575 * Caller only wants the current f_offset value. Assume that
576 * the long and shorter integer types reads are atomic.
578 if ((flags & FOF_NOLOCK) != 0)
579 return (fp->f_offset);
583 * According to McKusick the vn lock was protecting f_offset here.
584 * It is now protected by the FOFFSET_LOCKED flag.
586 mtxp = mtx_pool_find(mtxpool_sleep, fp);
588 if ((flags & FOF_NOLOCK) == 0) {
589 while (fp->f_vnread_flags & FOFFSET_LOCKED) {
590 fp->f_vnread_flags |= FOFFSET_LOCK_WAITING;
591 msleep(&fp->f_vnread_flags, mtxp, PUSER -1,
594 fp->f_vnread_flags |= FOFFSET_LOCKED;
602 foffset_unlock(struct file *fp, off_t val, int flags)
606 KASSERT((flags & FOF_OFFSET) == 0, ("FOF_OFFSET passed"));
608 #if OFF_MAX <= LONG_MAX
609 if ((flags & FOF_NOLOCK) != 0) {
610 if ((flags & FOF_NOUPDATE) == 0)
612 if ((flags & FOF_NEXTOFF) != 0)
618 mtxp = mtx_pool_find(mtxpool_sleep, fp);
620 if ((flags & FOF_NOUPDATE) == 0)
622 if ((flags & FOF_NEXTOFF) != 0)
624 if ((flags & FOF_NOLOCK) == 0) {
625 KASSERT((fp->f_vnread_flags & FOFFSET_LOCKED) != 0,
626 ("Lost FOFFSET_LOCKED"));
627 if (fp->f_vnread_flags & FOFFSET_LOCK_WAITING)
628 wakeup(&fp->f_vnread_flags);
629 fp->f_vnread_flags = 0;
635 foffset_lock_uio(struct file *fp, struct uio *uio, int flags)
638 if ((flags & FOF_OFFSET) == 0)
639 uio->uio_offset = foffset_lock(fp, flags);
643 foffset_unlock_uio(struct file *fp, struct uio *uio, int flags)
646 if ((flags & FOF_OFFSET) == 0)
647 foffset_unlock(fp, uio->uio_offset, flags);
651 get_advice(struct file *fp, struct uio *uio)
656 ret = POSIX_FADV_NORMAL;
657 if (fp->f_advice == NULL)
660 mtxp = mtx_pool_find(mtxpool_sleep, fp);
662 if (uio->uio_offset >= fp->f_advice->fa_start &&
663 uio->uio_offset + uio->uio_resid <= fp->f_advice->fa_end)
664 ret = fp->f_advice->fa_advice;
670 * File table vnode read routine.
673 vn_read(fp, uio, active_cred, flags, td)
676 struct ucred *active_cred;
684 off_t offset, start, end;
686 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
688 KASSERT(flags & FOF_OFFSET, ("No FOF_OFFSET"));
691 if (fp->f_flag & FNONBLOCK)
693 if (fp->f_flag & O_DIRECT)
695 advice = get_advice(fp, uio);
696 vn_lock(vp, LK_SHARED | LK_RETRY);
699 case POSIX_FADV_NORMAL:
700 case POSIX_FADV_SEQUENTIAL:
701 case POSIX_FADV_NOREUSE:
702 ioflag |= sequential_heuristic(uio, fp);
704 case POSIX_FADV_RANDOM:
705 /* Disable read-ahead for random I/O. */
708 offset = uio->uio_offset;
711 error = mac_vnode_check_read(active_cred, fp->f_cred, vp);
714 error = VOP_READ(vp, uio, ioflag, fp->f_cred);
715 fp->f_nextoff = uio->uio_offset;
717 if (error == 0 && advice == POSIX_FADV_NOREUSE &&
718 offset != uio->uio_offset) {
720 * Use POSIX_FADV_DONTNEED to flush clean pages and
721 * buffers for the backing file after a
722 * POSIX_FADV_NOREUSE read(2). To optimize the common
723 * case of using POSIX_FADV_NOREUSE with sequential
724 * access, track the previous implicit DONTNEED
725 * request and grow this request to include the
726 * current read(2) in addition to the previous
727 * DONTNEED. With purely sequential access this will
728 * cause the DONTNEED requests to continously grow to
729 * cover all of the previously read regions of the
730 * file. This allows filesystem blocks that are
731 * accessed by multiple calls to read(2) to be flushed
732 * once the last read(2) finishes.
735 end = uio->uio_offset - 1;
736 mtxp = mtx_pool_find(mtxpool_sleep, fp);
738 if (fp->f_advice != NULL &&
739 fp->f_advice->fa_advice == POSIX_FADV_NOREUSE) {
740 if (start != 0 && fp->f_advice->fa_prevend + 1 == start)
741 start = fp->f_advice->fa_prevstart;
742 else if (fp->f_advice->fa_prevstart != 0 &&
743 fp->f_advice->fa_prevstart == end + 1)
744 end = fp->f_advice->fa_prevend;
745 fp->f_advice->fa_prevstart = start;
746 fp->f_advice->fa_prevend = end;
749 error = VOP_ADVISE(vp, start, end, POSIX_FADV_DONTNEED);
755 * File table vnode write routine.
758 vn_write(fp, uio, active_cred, flags, td)
761 struct ucred *active_cred;
768 int error, ioflag, lock_flags;
770 off_t offset, start, end;
772 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
774 KASSERT(flags & FOF_OFFSET, ("No FOF_OFFSET"));
776 if (vp->v_type == VREG)
779 if (vp->v_type == VREG && (fp->f_flag & O_APPEND))
781 if (fp->f_flag & FNONBLOCK)
783 if (fp->f_flag & O_DIRECT)
785 if ((fp->f_flag & O_FSYNC) ||
786 (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)))
789 if (vp->v_type != VCHR &&
790 (error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
793 advice = get_advice(fp, uio);
795 if (MNT_SHARED_WRITES(mp) ||
796 (mp == NULL && MNT_SHARED_WRITES(vp->v_mount))) {
797 lock_flags = LK_SHARED;
799 lock_flags = LK_EXCLUSIVE;
802 vn_lock(vp, lock_flags | LK_RETRY);
804 case POSIX_FADV_NORMAL:
805 case POSIX_FADV_SEQUENTIAL:
806 case POSIX_FADV_NOREUSE:
807 ioflag |= sequential_heuristic(uio, fp);
809 case POSIX_FADV_RANDOM:
810 /* XXX: Is this correct? */
813 offset = uio->uio_offset;
816 error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
819 error = VOP_WRITE(vp, uio, ioflag, fp->f_cred);
820 fp->f_nextoff = uio->uio_offset;
822 if (vp->v_type != VCHR)
823 vn_finished_write(mp);
824 if (error == 0 && advice == POSIX_FADV_NOREUSE &&
825 offset != uio->uio_offset) {
827 * Use POSIX_FADV_DONTNEED to flush clean pages and
828 * buffers for the backing file after a
829 * POSIX_FADV_NOREUSE write(2). To optimize the
830 * common case of using POSIX_FADV_NOREUSE with
831 * sequential access, track the previous implicit
832 * DONTNEED request and grow this request to include
833 * the current write(2) in addition to the previous
834 * DONTNEED. With purely sequential access this will
835 * cause the DONTNEED requests to continously grow to
836 * cover all of the previously written regions of the
839 * Note that the blocks just written are almost
840 * certainly still dirty, so this only works when
841 * VOP_ADVISE() calls from subsequent writes push out
842 * the data written by this write(2) once the backing
843 * buffers are clean. However, as compared to forcing
844 * IO_DIRECT, this gives much saner behavior. Write
845 * clustering is still allowed, and clean pages are
846 * merely moved to the cache page queue rather than
847 * outright thrown away. This means a subsequent
848 * read(2) can still avoid hitting the disk if the
849 * pages have not been reclaimed.
851 * This does make POSIX_FADV_NOREUSE largely useless
852 * with non-sequential access. However, sequential
853 * access is the more common use case and the flag is
857 end = uio->uio_offset - 1;
858 mtxp = mtx_pool_find(mtxpool_sleep, fp);
860 if (fp->f_advice != NULL &&
861 fp->f_advice->fa_advice == POSIX_FADV_NOREUSE) {
862 if (start != 0 && fp->f_advice->fa_prevend + 1 == start)
863 start = fp->f_advice->fa_prevstart;
864 else if (fp->f_advice->fa_prevstart != 0 &&
865 fp->f_advice->fa_prevstart == end + 1)
866 end = fp->f_advice->fa_prevend;
867 fp->f_advice->fa_prevstart = start;
868 fp->f_advice->fa_prevend = end;
871 error = VOP_ADVISE(vp, start, end, POSIX_FADV_DONTNEED);
878 static const int io_hold_cnt = 16;
879 static int vn_io_fault_enable = 1;
880 SYSCTL_INT(_debug, OID_AUTO, vn_io_fault_enable, CTLFLAG_RW,
881 &vn_io_fault_enable, 0, "Enable vn_io_fault lock avoidance");
882 static u_long vn_io_faults_cnt;
883 SYSCTL_ULONG(_debug, OID_AUTO, vn_io_faults, CTLFLAG_RD,
884 &vn_io_faults_cnt, 0, "Count of vn_io_fault lock avoidance triggers");
887 * The vn_io_fault() is a wrapper around vn_read() and vn_write() to
888 * prevent the following deadlock:
890 * Assume that the thread A reads from the vnode vp1 into userspace
891 * buffer buf1 backed by the pages of vnode vp2. If a page in buf1 is
892 * currently not resident, then system ends up with the call chain
893 * vn_read() -> VOP_READ(vp1) -> uiomove() -> [Page Fault] ->
894 * vm_fault(buf1) -> vnode_pager_getpages(vp2) -> VOP_GETPAGES(vp2)
895 * which establishes lock order vp1->vn_lock, then vp2->vn_lock.
896 * If, at the same time, thread B reads from vnode vp2 into buffer buf2
897 * backed by the pages of vnode vp1, and some page in buf2 is not
898 * resident, we get a reversed order vp2->vn_lock, then vp1->vn_lock.
900 * To prevent the lock order reversal and deadlock, vn_io_fault() does
901 * not allow page faults to happen during VOP_READ() or VOP_WRITE().
902 * Instead, it first tries to do the whole range i/o with pagefaults
903 * disabled. If all pages in the i/o buffer are resident and mapped,
904 * VOP will succeed (ignoring the genuine filesystem errors).
905 * Otherwise, we get back EFAULT, and vn_io_fault() falls back to do
906 * i/o in chunks, with all pages in the chunk prefaulted and held
907 * using vm_fault_quick_hold_pages().
909 * Filesystems using this deadlock avoidance scheme should use the
910 * array of the held pages from uio, saved in the curthread->td_ma,
911 * instead of doing uiomove(). A helper function
912 * vn_io_fault_uiomove() converts uiomove request into
913 * uiomove_fromphys() over td_ma array.
915 * Since vnode locks do not cover the whole i/o anymore, rangelocks
916 * make the current i/o request atomic with respect to other i/os and
920 vn_io_fault(struct file *fp, struct uio *uio, struct ucred *active_cred,
921 int flags, struct thread *td)
923 vm_page_t ma[io_hold_cnt + 2];
924 struct uio *uio_clone, short_uio;
925 struct iovec short_iovec[1];
930 vm_page_t *prev_td_ma;
931 int cnt, error, save, saveheld, prev_td_ma_cnt;
932 vm_offset_t addr, end;
937 if (uio->uio_rw == UIO_READ)
942 foffset_lock_uio(fp, uio, flags);
944 if (uio->uio_segflg != UIO_USERSPACE || vp->v_type != VREG ||
945 ((mp = vp->v_mount) != NULL &&
946 (mp->mnt_kern_flag & MNTK_NO_IOPF) == 0) ||
947 !vn_io_fault_enable) {
948 error = doio(fp, uio, active_cred, flags | FOF_OFFSET, td);
953 * The UFS follows IO_UNIT directive and replays back both
954 * uio_offset and uio_resid if an error is encountered during the
955 * operation. But, since the iovec may be already advanced,
956 * uio is still in an inconsistent state.
958 * Cache a copy of the original uio, which is advanced to the redo
959 * point using UIO_NOCOPY below.
961 uio_clone = cloneuio(uio);
962 resid = uio->uio_resid;
964 short_uio.uio_segflg = UIO_USERSPACE;
965 short_uio.uio_rw = uio->uio_rw;
966 short_uio.uio_td = uio->uio_td;
968 if (uio->uio_rw == UIO_READ) {
969 prot = VM_PROT_WRITE;
970 rl_cookie = vn_rangelock_rlock(vp, uio->uio_offset,
971 uio->uio_offset + uio->uio_resid);
974 if ((fp->f_flag & O_APPEND) != 0 || (flags & FOF_OFFSET) == 0)
975 /* For appenders, punt and lock the whole range. */
976 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
978 rl_cookie = vn_rangelock_wlock(vp, uio->uio_offset,
979 uio->uio_offset + uio->uio_resid);
982 save = vm_fault_disable_pagefaults();
983 error = doio(fp, uio, active_cred, flags | FOF_OFFSET, td);
987 atomic_add_long(&vn_io_faults_cnt, 1);
988 uio_clone->uio_segflg = UIO_NOCOPY;
989 uiomove(NULL, resid - uio->uio_resid, uio_clone);
990 uio_clone->uio_segflg = uio->uio_segflg;
992 saveheld = curthread_pflags_set(TDP_UIOHELD);
993 prev_td_ma = td->td_ma;
994 prev_td_ma_cnt = td->td_ma_cnt;
996 while (uio_clone->uio_resid != 0) {
997 len = uio_clone->uio_iov->iov_len;
999 KASSERT(uio_clone->uio_iovcnt >= 1,
1000 ("iovcnt underflow"));
1001 uio_clone->uio_iov++;
1002 uio_clone->uio_iovcnt--;
1006 addr = (vm_offset_t)uio_clone->uio_iov->iov_base;
1007 end = round_page(addr + len);
1008 cnt = howmany(end - trunc_page(addr), PAGE_SIZE);
1010 * A perfectly misaligned address and length could cause
1011 * both the start and the end of the chunk to use partial
1012 * page. +2 accounts for such a situation.
1014 if (cnt > io_hold_cnt + 2) {
1015 len = io_hold_cnt * PAGE_SIZE;
1016 KASSERT(howmany(round_page(addr + len) -
1017 trunc_page(addr), PAGE_SIZE) <= io_hold_cnt + 2,
1020 cnt = vm_fault_quick_hold_pages(&td->td_proc->p_vmspace->vm_map,
1021 addr, len, prot, ma, io_hold_cnt + 2);
1026 short_uio.uio_iov = &short_iovec[0];
1027 short_iovec[0].iov_base = (void *)addr;
1028 short_uio.uio_iovcnt = 1;
1029 short_uio.uio_resid = short_iovec[0].iov_len = len;
1030 short_uio.uio_offset = uio_clone->uio_offset;
1032 td->td_ma_cnt = cnt;
1034 error = doio(fp, &short_uio, active_cred, flags | FOF_OFFSET,
1036 vm_page_unhold_pages(ma, cnt);
1037 adv = len - short_uio.uio_resid;
1039 uio_clone->uio_iov->iov_base =
1040 (char *)uio_clone->uio_iov->iov_base + adv;
1041 uio_clone->uio_iov->iov_len -= adv;
1042 uio_clone->uio_resid -= adv;
1043 uio_clone->uio_offset += adv;
1045 uio->uio_resid -= adv;
1046 uio->uio_offset += adv;
1048 if (error != 0 || adv == 0)
1051 td->td_ma = prev_td_ma;
1052 td->td_ma_cnt = prev_td_ma_cnt;
1053 curthread_pflags_restore(saveheld);
1055 vm_fault_enable_pagefaults(save);
1056 vn_rangelock_unlock(vp, rl_cookie);
1057 free(uio_clone, M_IOV);
1059 foffset_unlock_uio(fp, uio, flags);
1064 * Helper function to perform the requested uiomove operation using
1065 * the held pages for io->uio_iov[0].iov_base buffer instead of
1066 * copyin/copyout. Access to the pages with uiomove_fromphys()
1067 * instead of iov_base prevents page faults that could occur due to
1068 * pmap_collect() invalidating the mapping created by
1069 * vm_fault_quick_hold_pages(), or pageout daemon, page laundry or
1070 * object cleanup revoking the write access from page mappings.
1072 * Filesystems specified MNTK_NO_IOPF shall use vn_io_fault_uiomove()
1073 * instead of plain uiomove().
1076 vn_io_fault_uiomove(char *data, int xfersize, struct uio *uio)
1078 struct uio transp_uio;
1079 struct iovec transp_iov[1];
1085 if ((td->td_pflags & TDP_UIOHELD) == 0 ||
1086 uio->uio_segflg != UIO_USERSPACE)
1087 return (uiomove(data, xfersize, uio));
1089 KASSERT(uio->uio_iovcnt == 1, ("uio_iovcnt %d", uio->uio_iovcnt));
1090 transp_iov[0].iov_base = data;
1091 transp_uio.uio_iov = &transp_iov[0];
1092 transp_uio.uio_iovcnt = 1;
1093 if (xfersize > uio->uio_resid)
1094 xfersize = uio->uio_resid;
1095 transp_uio.uio_resid = transp_iov[0].iov_len = xfersize;
1096 transp_uio.uio_offset = 0;
1097 transp_uio.uio_segflg = UIO_SYSSPACE;
1099 * Since transp_iov points to data, and td_ma page array
1100 * corresponds to original uio->uio_iov, we need to invert the
1101 * direction of the i/o operation as passed to
1102 * uiomove_fromphys().
1104 switch (uio->uio_rw) {
1106 transp_uio.uio_rw = UIO_READ;
1109 transp_uio.uio_rw = UIO_WRITE;
1112 transp_uio.uio_td = uio->uio_td;
1113 error = uiomove_fromphys(td->td_ma,
1114 ((vm_offset_t)uio->uio_iov->iov_base) & PAGE_MASK,
1115 xfersize, &transp_uio);
1116 adv = xfersize - transp_uio.uio_resid;
1118 (((vm_offset_t)uio->uio_iov->iov_base + adv) >> PAGE_SHIFT) -
1119 (((vm_offset_t)uio->uio_iov->iov_base) >> PAGE_SHIFT);
1121 KASSERT(td->td_ma_cnt >= pgadv, ("consumed pages %d %d", td->td_ma_cnt,
1123 td->td_ma_cnt -= pgadv;
1124 uio->uio_iov->iov_base = (char *)uio->uio_iov->iov_base + adv;
1125 uio->uio_iov->iov_len -= adv;
1126 uio->uio_resid -= adv;
1127 uio->uio_offset += adv;
1132 vn_io_fault_pgmove(vm_page_t ma[], vm_offset_t offset, int xfersize,
1136 vm_offset_t iov_base;
1140 if ((td->td_pflags & TDP_UIOHELD) == 0 ||
1141 uio->uio_segflg != UIO_USERSPACE)
1142 return (uiomove_fromphys(ma, offset, xfersize, uio));
1144 KASSERT(uio->uio_iovcnt == 1, ("uio_iovcnt %d", uio->uio_iovcnt));
1145 cnt = xfersize > uio->uio_resid ? uio->uio_resid : xfersize;
1146 iov_base = (vm_offset_t)uio->uio_iov->iov_base;
1147 switch (uio->uio_rw) {
1149 pmap_copy_pages(td->td_ma, iov_base & PAGE_MASK, ma,
1153 pmap_copy_pages(ma, offset, td->td_ma, iov_base & PAGE_MASK,
1157 pgadv = ((iov_base + cnt) >> PAGE_SHIFT) - (iov_base >> PAGE_SHIFT);
1159 KASSERT(td->td_ma_cnt >= pgadv, ("consumed pages %d %d", td->td_ma_cnt,
1161 td->td_ma_cnt -= pgadv;
1162 uio->uio_iov->iov_base = (char *)(iov_base + cnt);
1163 uio->uio_iov->iov_len -= cnt;
1164 uio->uio_resid -= cnt;
1165 uio->uio_offset += cnt;
1171 * File table truncate routine.
1174 vn_truncate(struct file *fp, off_t length, struct ucred *active_cred,
1186 * Lock the whole range for truncation. Otherwise split i/o
1187 * might happen partly before and partly after the truncation.
1189 rl_cookie = vn_rangelock_wlock(vp, 0, OFF_MAX);
1190 error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
1193 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1194 if (vp->v_type == VDIR) {
1199 error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
1203 error = vn_writechk(vp);
1206 vattr.va_size = length;
1207 error = VOP_SETATTR(vp, &vattr, fp->f_cred);
1211 vn_finished_write(mp);
1213 vn_rangelock_unlock(vp, rl_cookie);
1218 * File table vnode stat routine.
1221 vn_statfile(fp, sb, active_cred, td)
1224 struct ucred *active_cred;
1227 struct vnode *vp = fp->f_vnode;
1230 vn_lock(vp, LK_SHARED | LK_RETRY);
1231 error = vn_stat(vp, sb, active_cred, fp->f_cred, td);
1238 * Stat a vnode; implementation for the stat syscall
1241 vn_stat(vp, sb, active_cred, file_cred, td)
1243 register struct stat *sb;
1244 struct ucred *active_cred;
1245 struct ucred *file_cred;
1249 register struct vattr *vap;
1254 error = mac_vnode_check_stat(active_cred, file_cred, vp);
1262 * Initialize defaults for new and unusual fields, so that file
1263 * systems which don't support these fields don't need to know
1266 vap->va_birthtime.tv_sec = -1;
1267 vap->va_birthtime.tv_nsec = 0;
1268 vap->va_fsid = VNOVAL;
1269 vap->va_rdev = NODEV;
1271 error = VOP_GETATTR(vp, vap, active_cred);
1276 * Zero the spare stat fields
1278 bzero(sb, sizeof *sb);
1281 * Copy from vattr table
1283 if (vap->va_fsid != VNOVAL)
1284 sb->st_dev = vap->va_fsid;
1286 sb->st_dev = vp->v_mount->mnt_stat.f_fsid.val[0];
1287 sb->st_ino = vap->va_fileid;
1288 mode = vap->va_mode;
1289 switch (vap->va_type) {
1315 sb->st_nlink = vap->va_nlink;
1316 sb->st_uid = vap->va_uid;
1317 sb->st_gid = vap->va_gid;
1318 sb->st_rdev = vap->va_rdev;
1319 if (vap->va_size > OFF_MAX)
1321 sb->st_size = vap->va_size;
1322 sb->st_atim = vap->va_atime;
1323 sb->st_mtim = vap->va_mtime;
1324 sb->st_ctim = vap->va_ctime;
1325 sb->st_birthtim = vap->va_birthtime;
1328 * According to www.opengroup.org, the meaning of st_blksize is
1329 * "a filesystem-specific preferred I/O block size for this
1330 * object. In some filesystem types, this may vary from file
1332 * Use miminum/default of PAGE_SIZE (e.g. for VCHR).
1335 sb->st_blksize = max(PAGE_SIZE, vap->va_blocksize);
1337 sb->st_flags = vap->va_flags;
1338 if (priv_check(td, PRIV_VFS_GENERATION))
1341 sb->st_gen = vap->va_gen;
1343 sb->st_blocks = vap->va_bytes / S_BLKSIZE;
1348 * File table vnode ioctl routine.
1351 vn_ioctl(fp, com, data, active_cred, td)
1355 struct ucred *active_cred;
1363 switch (vp->v_type) {
1368 vn_lock(vp, LK_SHARED | LK_RETRY);
1369 error = VOP_GETATTR(vp, &vattr, active_cred);
1372 *(int *)data = vattr.va_size - fp->f_offset;
1378 return (VOP_IOCTL(vp, com, data, fp->f_flag,
1387 * File table vnode poll routine.
1390 vn_poll(fp, events, active_cred, td)
1393 struct ucred *active_cred;
1401 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1402 error = mac_vnode_check_poll(active_cred, fp->f_cred, vp);
1407 error = VOP_POLL(vp, events, fp->f_cred, td);
1412 * Acquire the requested lock and then check for validity. LK_RETRY
1413 * permits vn_lock to return doomed vnodes.
1416 _vn_lock(struct vnode *vp, int flags, char *file, int line)
1420 VNASSERT((flags & LK_TYPE_MASK) != 0, vp,
1421 ("vn_lock called with no locktype."));
1423 #ifdef DEBUG_VFS_LOCKS
1424 KASSERT(vp->v_holdcnt != 0,
1425 ("vn_lock %p: zero hold count", vp));
1427 error = VOP_LOCK1(vp, flags, file, line);
1428 flags &= ~LK_INTERLOCK; /* Interlock is always dropped. */
1429 KASSERT((flags & LK_RETRY) == 0 || error == 0,
1430 ("LK_RETRY set with incompatible flags (0x%x) or an error occured (%d)",
1433 * Callers specify LK_RETRY if they wish to get dead vnodes.
1434 * If RETRY is not set, we return ENOENT instead.
1436 if (error == 0 && vp->v_iflag & VI_DOOMED &&
1437 (flags & LK_RETRY) == 0) {
1442 } while (flags & LK_RETRY && error != 0);
1447 * File table vnode close routine.
1450 vn_closefile(fp, td)
1459 fp->f_ops = &badfileops;
1461 if (fp->f_type == DTYPE_VNODE && fp->f_flag & FHASLOCK)
1464 error = vn_close(vp, fp->f_flag, fp->f_cred, td);
1466 if (fp->f_type == DTYPE_VNODE && fp->f_flag & FHASLOCK) {
1467 lf.l_whence = SEEK_SET;
1470 lf.l_type = F_UNLCK;
1471 (void) VOP_ADVLOCK(vp, fp, F_UNLCK, &lf, F_FLOCK);
1478 * Preparing to start a filesystem write operation. If the operation is
1479 * permitted, then we bump the count of operations in progress and
1480 * proceed. If a suspend request is in progress, we wait until the
1481 * suspension is over, and then proceed.
1484 vn_start_write_locked(struct mount *mp, int flags)
1488 mtx_assert(MNT_MTX(mp), MA_OWNED);
1492 * Check on status of suspension.
1494 if ((curthread->td_pflags & TDP_IGNSUSP) == 0 ||
1495 mp->mnt_susp_owner != curthread) {
1496 while ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
1497 if (flags & V_NOWAIT) {
1498 error = EWOULDBLOCK;
1501 error = msleep(&mp->mnt_flag, MNT_MTX(mp),
1502 (PUSER - 1) | (flags & PCATCH), "suspfs", 0);
1507 if (flags & V_XSLEEP)
1509 mp->mnt_writeopcount++;
1511 if (error != 0 || (flags & V_XSLEEP) != 0)
1518 vn_start_write(vp, mpp, flags)
1528 * If a vnode is provided, get and return the mount point that
1529 * to which it will write.
1532 if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
1534 if (error != EOPNOTSUPP)
1539 if ((mp = *mpp) == NULL)
1543 * VOP_GETWRITEMOUNT() returns with the mp refcount held through
1545 * As long as a vnode is not provided we need to acquire a
1546 * refcount for the provided mountpoint too, in order to
1547 * emulate a vfs_ref().
1553 return (vn_start_write_locked(mp, flags));
1557 * Secondary suspension. Used by operations such as vop_inactive
1558 * routines that are needed by the higher level functions. These
1559 * are allowed to proceed until all the higher level functions have
1560 * completed (indicated by mnt_writeopcount dropping to zero). At that
1561 * time, these operations are halted until the suspension is over.
1564 vn_start_secondary_write(vp, mpp, flags)
1574 if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
1576 if (error != EOPNOTSUPP)
1582 * If we are not suspended or have not yet reached suspended
1583 * mode, then let the operation proceed.
1585 if ((mp = *mpp) == NULL)
1589 * VOP_GETWRITEMOUNT() returns with the mp refcount held through
1591 * As long as a vnode is not provided we need to acquire a
1592 * refcount for the provided mountpoint too, in order to
1593 * emulate a vfs_ref().
1598 if ((mp->mnt_kern_flag & (MNTK_SUSPENDED | MNTK_SUSPEND2)) == 0) {
1599 mp->mnt_secondary_writes++;
1600 mp->mnt_secondary_accwrites++;
1604 if (flags & V_NOWAIT) {
1607 return (EWOULDBLOCK);
1610 * Wait for the suspension to finish.
1612 error = msleep(&mp->mnt_flag, MNT_MTX(mp),
1613 (PUSER - 1) | (flags & PCATCH) | PDROP, "suspfs", 0);
1621 * Filesystem write operation has completed. If we are suspending and this
1622 * operation is the last one, notify the suspender that the suspension is
1626 vn_finished_write(mp)
1633 mp->mnt_writeopcount--;
1634 if (mp->mnt_writeopcount < 0)
1635 panic("vn_finished_write: neg cnt");
1636 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 &&
1637 mp->mnt_writeopcount <= 0)
1638 wakeup(&mp->mnt_writeopcount);
1644 * Filesystem secondary write operation has completed. If we are
1645 * suspending and this operation is the last one, notify the suspender
1646 * that the suspension is now in effect.
1649 vn_finished_secondary_write(mp)
1656 mp->mnt_secondary_writes--;
1657 if (mp->mnt_secondary_writes < 0)
1658 panic("vn_finished_secondary_write: neg cnt");
1659 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 &&
1660 mp->mnt_secondary_writes <= 0)
1661 wakeup(&mp->mnt_secondary_writes);
1668 * Request a filesystem to suspend write operations.
1671 vfs_write_suspend(struct mount *mp, int flags)
1676 if (mp->mnt_susp_owner == curthread) {
1680 while (mp->mnt_kern_flag & MNTK_SUSPEND)
1681 msleep(&mp->mnt_flag, MNT_MTX(mp), PUSER - 1, "wsuspfs", 0);
1684 * Unmount holds a write reference on the mount point. If we
1685 * own busy reference and drain for writers, we deadlock with
1686 * the reference draining in the unmount path. Callers of
1687 * vfs_write_suspend() must specify VS_SKIP_UNMOUNT if
1688 * vfs_busy() reference is owned and caller is not in the
1691 if ((flags & VS_SKIP_UNMOUNT) != 0 &&
1692 (mp->mnt_kern_flag & MNTK_UNMOUNT) != 0) {
1697 mp->mnt_kern_flag |= MNTK_SUSPEND;
1698 mp->mnt_susp_owner = curthread;
1699 if (mp->mnt_writeopcount > 0)
1700 (void) msleep(&mp->mnt_writeopcount,
1701 MNT_MTX(mp), (PUSER - 1)|PDROP, "suspwt", 0);
1704 if ((error = VFS_SYNC(mp, MNT_SUSPEND)) != 0)
1705 vfs_write_resume(mp, 0);
1710 * Request a filesystem to resume write operations.
1713 vfs_write_resume(struct mount *mp, int flags)
1717 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
1718 KASSERT(mp->mnt_susp_owner == curthread, ("mnt_susp_owner"));
1719 mp->mnt_kern_flag &= ~(MNTK_SUSPEND | MNTK_SUSPEND2 |
1721 mp->mnt_susp_owner = NULL;
1722 wakeup(&mp->mnt_writeopcount);
1723 wakeup(&mp->mnt_flag);
1724 curthread->td_pflags &= ~TDP_IGNSUSP;
1725 if ((flags & VR_START_WRITE) != 0) {
1727 mp->mnt_writeopcount++;
1730 if ((flags & VR_NO_SUSPCLR) == 0)
1732 } else if ((flags & VR_START_WRITE) != 0) {
1734 vn_start_write_locked(mp, 0);
1741 * Implement kqueues for files by translating it to vnode operation.
1744 vn_kqfilter(struct file *fp, struct knote *kn)
1747 return (VOP_KQFILTER(fp->f_vnode, kn));
1751 * Simplified in-kernel wrapper calls for extended attribute access.
1752 * Both calls pass in a NULL credential, authorizing as "kernel" access.
1753 * Set IO_NODELOCKED in ioflg if the vnode is already locked.
1756 vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace,
1757 const char *attrname, int *buflen, char *buf, struct thread *td)
1763 iov.iov_len = *buflen;
1766 auio.uio_iov = &iov;
1767 auio.uio_iovcnt = 1;
1768 auio.uio_rw = UIO_READ;
1769 auio.uio_segflg = UIO_SYSSPACE;
1771 auio.uio_offset = 0;
1772 auio.uio_resid = *buflen;
1774 if ((ioflg & IO_NODELOCKED) == 0)
1775 vn_lock(vp, LK_SHARED | LK_RETRY);
1777 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
1779 /* authorize attribute retrieval as kernel */
1780 error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL,
1783 if ((ioflg & IO_NODELOCKED) == 0)
1787 *buflen = *buflen - auio.uio_resid;
1794 * XXX failure mode if partially written?
1797 vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace,
1798 const char *attrname, int buflen, char *buf, struct thread *td)
1805 iov.iov_len = buflen;
1808 auio.uio_iov = &iov;
1809 auio.uio_iovcnt = 1;
1810 auio.uio_rw = UIO_WRITE;
1811 auio.uio_segflg = UIO_SYSSPACE;
1813 auio.uio_offset = 0;
1814 auio.uio_resid = buflen;
1816 if ((ioflg & IO_NODELOCKED) == 0) {
1817 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
1819 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1822 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
1824 /* authorize attribute setting as kernel */
1825 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, td);
1827 if ((ioflg & IO_NODELOCKED) == 0) {
1828 vn_finished_write(mp);
1836 vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace,
1837 const char *attrname, struct thread *td)
1842 if ((ioflg & IO_NODELOCKED) == 0) {
1843 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
1845 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1848 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
1850 /* authorize attribute removal as kernel */
1851 error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL, td);
1852 if (error == EOPNOTSUPP)
1853 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL,
1856 if ((ioflg & IO_NODELOCKED) == 0) {
1857 vn_finished_write(mp);
1865 vn_vget_ino(struct vnode *vp, ino_t ino, int lkflags, struct vnode **rvp)
1871 ltype = VOP_ISLOCKED(vp);
1872 KASSERT(ltype == LK_EXCLUSIVE || ltype == LK_SHARED,
1873 ("vn_vget_ino: vp not locked"));
1874 error = vfs_busy(mp, MBF_NOWAIT);
1878 error = vfs_busy(mp, 0);
1879 vn_lock(vp, ltype | LK_RETRY);
1883 if (vp->v_iflag & VI_DOOMED) {
1889 error = VFS_VGET(mp, ino, lkflags, rvp);
1891 vn_lock(vp, ltype | LK_RETRY);
1892 if (vp->v_iflag & VI_DOOMED) {
1901 vn_rlimit_fsize(const struct vnode *vp, const struct uio *uio,
1902 const struct thread *td)
1905 if (vp->v_type != VREG || td == NULL)
1907 PROC_LOCK(td->td_proc);
1908 if ((uoff_t)uio->uio_offset + uio->uio_resid >
1909 lim_cur(td->td_proc, RLIMIT_FSIZE)) {
1910 kern_psignal(td->td_proc, SIGXFSZ);
1911 PROC_UNLOCK(td->td_proc);
1914 PROC_UNLOCK(td->td_proc);
1919 vn_chmod(struct file *fp, mode_t mode, struct ucred *active_cred,
1926 vn_lock(vp, LK_SHARED | LK_RETRY);
1927 AUDIT_ARG_VNODE1(vp);
1930 return (setfmode(td, active_cred, vp, mode));
1934 vn_chown(struct file *fp, uid_t uid, gid_t gid, struct ucred *active_cred,
1941 vn_lock(vp, LK_SHARED | LK_RETRY);
1942 AUDIT_ARG_VNODE1(vp);
1945 return (setfown(td, active_cred, vp, uid, gid));
1949 vn_pages_remove(struct vnode *vp, vm_pindex_t start, vm_pindex_t end)
1953 if ((object = vp->v_object) == NULL)
1955 VM_OBJECT_WLOCK(object);
1956 vm_object_page_remove(object, start, end, 0);
1957 VM_OBJECT_WUNLOCK(object);
1961 vn_bmap_seekhole(struct vnode *vp, u_long cmd, off_t *off, struct ucred *cred)
1969 KASSERT(cmd == FIOSEEKHOLE || cmd == FIOSEEKDATA,
1970 ("Wrong command %lu", cmd));
1972 if (vn_lock(vp, LK_SHARED) != 0)
1974 if (vp->v_type != VREG) {
1978 error = VOP_GETATTR(vp, &va, cred);
1982 if (noff >= va.va_size) {
1986 bsize = vp->v_mount->mnt_stat.f_iosize;
1987 for (bn = noff / bsize; noff < va.va_size; bn++, noff += bsize) {
1988 error = VOP_BMAP(vp, bn, NULL, &bnp, NULL, NULL);
1989 if (error == EOPNOTSUPP) {
1993 if ((bnp == -1 && cmd == FIOSEEKHOLE) ||
1994 (bnp != -1 && cmd == FIOSEEKDATA)) {
2001 if (noff > va.va_size)
2003 /* noff == va.va_size. There is an implicit hole at the end of file. */
2004 if (cmd == FIOSEEKDATA)