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34 * @(#)vfs_vnops.c 8.2 (Berkeley) 1/21/94
37 #include <sys/cdefs.h>
38 __FBSDID("$FreeBSD$");
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/fcntl.h>
48 #include <sys/limits.h>
50 #include <sys/mount.h>
51 #include <sys/mutex.h>
52 #include <sys/namei.h>
53 #include <sys/vnode.h>
56 #include <sys/filio.h>
58 #include <sys/ttycom.h>
60 #include <sys/syslog.h>
61 #include <sys/unistd.h>
63 #include <security/mac/mac_framework.h>
65 static fo_rdwr_t vn_read;
66 static fo_rdwr_t vn_write;
67 static fo_truncate_t vn_truncate;
68 static fo_ioctl_t vn_ioctl;
69 static fo_poll_t vn_poll;
70 static fo_kqfilter_t vn_kqfilter;
71 static fo_stat_t vn_statfile;
72 static fo_close_t vn_closefile;
74 struct fileops vnops = {
77 .fo_truncate = vn_truncate,
80 .fo_kqfilter = vn_kqfilter,
81 .fo_stat = vn_statfile,
82 .fo_close = vn_closefile,
83 .fo_flags = DFLAG_PASSABLE | DFLAG_SEEKABLE
87 vn_open(ndp, flagp, cmode, fp)
88 struct nameidata *ndp;
92 struct thread *td = ndp->ni_cnd.cn_thread;
94 return (vn_open_cred(ndp, flagp, cmode, 0, td->td_ucred, fp));
98 * Common code for vnode open operations.
99 * Check permissions, and call the VOP_OPEN or VOP_CREATE routine.
101 * Note that this does NOT free nameidata for the successful case,
102 * due to the NDINIT being done elsewhere.
105 vn_open_cred(struct nameidata *ndp, int *flagp, int cmode, u_int vn_open_flags,
106 struct ucred *cred, struct file *fp)
110 struct thread *td = ndp->ni_cnd.cn_thread;
112 struct vattr *vap = &vat;
115 int vfslocked, mpsafe;
117 mpsafe = ndp->ni_cnd.cn_flags & MPSAFE;
121 if (fmode & O_CREAT) {
122 ndp->ni_cnd.cn_nameiop = CREATE;
123 ndp->ni_cnd.cn_flags = ISOPEN | LOCKPARENT | LOCKLEAF |
125 if ((fmode & O_EXCL) == 0 && (fmode & O_NOFOLLOW) == 0)
126 ndp->ni_cnd.cn_flags |= FOLLOW;
127 if (!(vn_open_flags & VN_OPEN_NOAUDIT))
128 ndp->ni_cnd.cn_flags |= AUDITVNODE1;
130 if ((error = namei(ndp)) != 0)
132 vfslocked = NDHASGIANT(ndp);
134 ndp->ni_cnd.cn_flags &= ~MPSAFE;
135 if (ndp->ni_vp == NULL) {
138 vap->va_mode = cmode;
140 vap->va_vaflags |= VA_EXCLUSIVE;
141 if (vn_start_write(ndp->ni_dvp, &mp, V_NOWAIT) != 0) {
142 NDFREE(ndp, NDF_ONLY_PNBUF);
144 VFS_UNLOCK_GIANT(vfslocked);
145 if ((error = vn_start_write(NULL, &mp,
146 V_XSLEEP | PCATCH)) != 0)
151 error = mac_vnode_check_create(cred, ndp->ni_dvp,
155 error = VOP_CREATE(ndp->ni_dvp, &ndp->ni_vp,
158 vn_finished_write(mp);
160 VFS_UNLOCK_GIANT(vfslocked);
161 NDFREE(ndp, NDF_ONLY_PNBUF);
167 if (ndp->ni_dvp == ndp->ni_vp)
173 if (fmode & O_EXCL) {
180 ndp->ni_cnd.cn_nameiop = LOOKUP;
181 ndp->ni_cnd.cn_flags = ISOPEN |
182 ((fmode & O_NOFOLLOW) ? NOFOLLOW : FOLLOW) |
184 if (!(fmode & FWRITE))
185 ndp->ni_cnd.cn_flags |= LOCKSHARED;
186 if (!(vn_open_flags & VN_OPEN_NOAUDIT))
187 ndp->ni_cnd.cn_flags |= AUDITVNODE1;
188 if ((error = namei(ndp)) != 0)
191 ndp->ni_cnd.cn_flags &= ~MPSAFE;
192 vfslocked = NDHASGIANT(ndp);
195 if (vp->v_type == VLNK) {
199 if (vp->v_type == VSOCK) {
204 if (fmode & (FWRITE | O_TRUNC)) {
205 if (vp->v_type == VDIR) {
215 if (fmode & O_APPEND)
218 error = mac_vnode_check_open(cred, vp, accmode);
222 if ((fmode & O_CREAT) == 0) {
223 if (accmode & VWRITE) {
224 error = vn_writechk(vp);
229 error = VOP_ACCESS(vp, accmode, cred, td);
234 if ((error = VOP_OPEN(vp, fmode, cred, td, fp)) != 0)
240 ASSERT_VOP_LOCKED(vp, "vn_open_cred");
242 VFS_UNLOCK_GIANT(vfslocked);
245 NDFREE(ndp, NDF_ONLY_PNBUF);
247 VFS_UNLOCK_GIANT(vfslocked);
254 * Check for write permissions on the specified vnode.
255 * Prototype text segments cannot be written.
259 register struct vnode *vp;
262 ASSERT_VOP_LOCKED(vp, "vn_writechk");
264 * If there's shared text associated with
265 * the vnode, try to free it up once. If
266 * we fail, we can't allow writing.
268 if (vp->v_vflag & VV_TEXT)
278 vn_close(vp, flags, file_cred, td)
279 register struct vnode *vp;
281 struct ucred *file_cred;
285 int error, lock_flags;
287 if (!(flags & FWRITE) && vp->v_mount != NULL &&
288 vp->v_mount->mnt_kern_flag & MNTK_EXTENDED_SHARED)
289 lock_flags = LK_SHARED;
291 lock_flags = LK_EXCLUSIVE;
293 VFS_ASSERT_GIANT(vp->v_mount);
295 vn_start_write(vp, &mp, V_WAIT);
296 vn_lock(vp, lock_flags | LK_RETRY);
297 if (flags & FWRITE) {
298 VNASSERT(vp->v_writecount > 0, vp,
299 ("vn_close: negative writecount"));
302 error = VOP_CLOSE(vp, flags, file_cred, td);
304 vn_finished_write(mp);
309 * Heuristic to detect sequential operation.
312 sequential_heuristic(struct uio *uio, struct file *fp)
316 * Offset 0 is handled specially. open() sets f_seqcount to 1 so
317 * that the first I/O is normally considered to be slightly
318 * sequential. Seeking to offset 0 doesn't change sequentiality
319 * unless previous seeks have reduced f_seqcount to 0, in which
320 * case offset 0 is not special.
322 if ((uio->uio_offset == 0 && fp->f_seqcount > 0) ||
323 uio->uio_offset == fp->f_nextoff) {
325 * f_seqcount is in units of fixed-size blocks so that it
326 * depends mainly on the amount of sequential I/O and not
327 * much on the number of sequential I/O's. The fixed size
328 * of 16384 is hard-coded here since it is (not quite) just
329 * a magic size that works well here. This size is more
330 * closely related to the best I/O size for real disks than
331 * to any block size used by software.
333 fp->f_seqcount += howmany(uio->uio_resid, 16384);
334 if (fp->f_seqcount > IO_SEQMAX)
335 fp->f_seqcount = IO_SEQMAX;
336 return (fp->f_seqcount << IO_SEQSHIFT);
339 /* Not sequential. Quickly draw-down sequentiality. */
340 if (fp->f_seqcount > 1)
348 * Package up an I/O request on a vnode into a uio and do it.
351 vn_rdwr(rw, vp, base, len, offset, segflg, ioflg, active_cred, file_cred,
360 struct ucred *active_cred;
361 struct ucred *file_cred;
369 int error, lock_flags;
371 VFS_ASSERT_GIANT(vp->v_mount);
373 if ((ioflg & IO_NODELOCKED) == 0) {
375 if (rw == UIO_WRITE) {
376 if (vp->v_type != VCHR &&
377 (error = vn_start_write(vp, &mp, V_WAIT | PCATCH))
380 if (MNT_SHARED_WRITES(mp) ||
381 ((mp == NULL) && MNT_SHARED_WRITES(vp->v_mount))) {
382 lock_flags = LK_SHARED;
384 lock_flags = LK_EXCLUSIVE;
386 vn_lock(vp, lock_flags | LK_RETRY);
388 vn_lock(vp, LK_SHARED | LK_RETRY);
391 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
392 auio.uio_iov = &aiov;
394 aiov.iov_base = base;
396 auio.uio_resid = len;
397 auio.uio_offset = offset;
398 auio.uio_segflg = segflg;
403 if ((ioflg & IO_NOMACCHECK) == 0) {
405 error = mac_vnode_check_read(active_cred, file_cred,
408 error = mac_vnode_check_write(active_cred, file_cred,
418 error = VOP_READ(vp, &auio, ioflg, cred);
420 error = VOP_WRITE(vp, &auio, ioflg, cred);
423 *aresid = auio.uio_resid;
425 if (auio.uio_resid && error == 0)
427 if ((ioflg & IO_NODELOCKED) == 0) {
428 if (rw == UIO_WRITE && vp->v_type != VCHR)
429 vn_finished_write(mp);
436 * Package up an I/O request on a vnode into a uio and do it. The I/O
437 * request is split up into smaller chunks and we try to avoid saturating
438 * the buffer cache while potentially holding a vnode locked, so we
439 * check bwillwrite() before calling vn_rdwr(). We also call uio_yield()
440 * to give other processes a chance to lock the vnode (either other processes
441 * core'ing the same binary, or unrelated processes scanning the directory).
444 vn_rdwr_inchunks(rw, vp, base, len, offset, segflg, ioflg, active_cred,
445 file_cred, aresid, td)
453 struct ucred *active_cred;
454 struct ucred *file_cred;
461 VFS_ASSERT_GIANT(vp->v_mount);
467 * Force `offset' to a multiple of MAXBSIZE except possibly
468 * for the first chunk, so that filesystems only need to
469 * write full blocks except possibly for the first and last
472 chunk = MAXBSIZE - (uoff_t)offset % MAXBSIZE;
476 if (rw != UIO_READ && vp->v_type == VREG)
479 error = vn_rdwr(rw, vp, base, chunk, offset, segflg,
480 ioflg, active_cred, file_cred, &iaresid, td);
481 len -= chunk; /* aresid calc already includes length */
485 base = (char *)base + chunk;
489 *aresid = len + iaresid;
494 * File table vnode read routine.
497 vn_read(fp, uio, active_cred, flags, td)
500 struct ucred *active_cred;
509 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
514 if (fp->f_flag & FNONBLOCK)
516 if (fp->f_flag & O_DIRECT)
518 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
520 * According to McKusick the vn lock was protecting f_offset here.
521 * It is now protected by the FOFFSET_LOCKED flag.
523 if ((flags & FOF_OFFSET) == 0) {
524 mtxp = mtx_pool_find(mtxpool_sleep, fp);
526 while(fp->f_vnread_flags & FOFFSET_LOCKED) {
527 fp->f_vnread_flags |= FOFFSET_LOCK_WAITING;
528 msleep(&fp->f_vnread_flags, mtxp, PUSER -1,
529 "vnread offlock", 0);
531 fp->f_vnread_flags |= FOFFSET_LOCKED;
533 vn_lock(vp, LK_SHARED | LK_RETRY);
534 uio->uio_offset = fp->f_offset;
536 vn_lock(vp, LK_SHARED | LK_RETRY);
538 ioflag |= sequential_heuristic(uio, fp);
541 error = mac_vnode_check_read(active_cred, fp->f_cred, vp);
544 error = VOP_READ(vp, uio, ioflag, fp->f_cred);
545 if ((flags & FOF_OFFSET) == 0) {
546 fp->f_offset = uio->uio_offset;
548 if (fp->f_vnread_flags & FOFFSET_LOCK_WAITING)
549 wakeup(&fp->f_vnread_flags);
550 fp->f_vnread_flags = 0;
553 fp->f_nextoff = uio->uio_offset;
555 VFS_UNLOCK_GIANT(vfslocked);
560 * File table vnode write routine.
563 vn_write(fp, uio, active_cred, flags, td)
566 struct ucred *active_cred;
572 int error, ioflag, lock_flags;
575 KASSERT(uio->uio_td == td, ("uio_td %p is not td %p",
578 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
579 if (vp->v_type == VREG)
582 if (vp->v_type == VREG && (fp->f_flag & O_APPEND))
584 if (fp->f_flag & FNONBLOCK)
586 if (fp->f_flag & O_DIRECT)
588 if ((fp->f_flag & O_FSYNC) ||
589 (vp->v_mount && (vp->v_mount->mnt_flag & MNT_SYNCHRONOUS)))
592 if (vp->v_type != VCHR &&
593 (error = vn_start_write(vp, &mp, V_WAIT | PCATCH)) != 0)
596 if ((MNT_SHARED_WRITES(mp) ||
597 ((mp == NULL) && MNT_SHARED_WRITES(vp->v_mount))) &&
598 (flags & FOF_OFFSET) != 0) {
599 lock_flags = LK_SHARED;
601 lock_flags = LK_EXCLUSIVE;
604 vn_lock(vp, lock_flags | LK_RETRY);
605 if ((flags & FOF_OFFSET) == 0)
606 uio->uio_offset = fp->f_offset;
607 ioflag |= sequential_heuristic(uio, fp);
609 error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
612 error = VOP_WRITE(vp, uio, ioflag, fp->f_cred);
613 if ((flags & FOF_OFFSET) == 0)
614 fp->f_offset = uio->uio_offset;
615 fp->f_nextoff = uio->uio_offset;
617 if (vp->v_type != VCHR)
618 vn_finished_write(mp);
620 VFS_UNLOCK_GIANT(vfslocked);
625 * File table truncate routine.
628 vn_truncate(fp, length, active_cred, td)
631 struct ucred *active_cred;
641 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
642 error = vn_start_write(vp, &mp, V_WAIT | PCATCH);
644 VFS_UNLOCK_GIANT(vfslocked);
647 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
648 if (vp->v_type == VDIR) {
653 error = mac_vnode_check_write(active_cred, fp->f_cred, vp);
657 error = vn_writechk(vp);
660 vattr.va_size = length;
661 error = VOP_SETATTR(vp, &vattr, fp->f_cred);
665 vn_finished_write(mp);
666 VFS_UNLOCK_GIANT(vfslocked);
671 * File table vnode stat routine.
674 vn_statfile(fp, sb, active_cred, td)
677 struct ucred *active_cred;
680 struct vnode *vp = fp->f_vnode;
684 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
685 vn_lock(vp, LK_SHARED | LK_RETRY);
686 error = vn_stat(vp, sb, active_cred, fp->f_cred, td);
688 VFS_UNLOCK_GIANT(vfslocked);
694 * Stat a vnode; implementation for the stat syscall
697 vn_stat(vp, sb, active_cred, file_cred, td)
699 register struct stat *sb;
700 struct ucred *active_cred;
701 struct ucred *file_cred;
705 register struct vattr *vap;
710 error = mac_vnode_check_stat(active_cred, file_cred, vp);
718 * Initialize defaults for new and unusual fields, so that file
719 * systems which don't support these fields don't need to know
722 vap->va_birthtime.tv_sec = -1;
723 vap->va_birthtime.tv_nsec = 0;
724 vap->va_fsid = VNOVAL;
725 vap->va_rdev = NODEV;
727 error = VOP_GETATTR(vp, vap, active_cred);
732 * Zero the spare stat fields
734 bzero(sb, sizeof *sb);
737 * Copy from vattr table
739 if (vap->va_fsid != VNOVAL)
740 sb->st_dev = vap->va_fsid;
742 sb->st_dev = vp->v_mount->mnt_stat.f_fsid.val[0];
743 sb->st_ino = vap->va_fileid;
745 switch (vap->va_type) {
771 sb->st_nlink = vap->va_nlink;
772 sb->st_uid = vap->va_uid;
773 sb->st_gid = vap->va_gid;
774 sb->st_rdev = vap->va_rdev;
775 if (vap->va_size > OFF_MAX)
777 sb->st_size = vap->va_size;
778 sb->st_atimespec = vap->va_atime;
779 sb->st_mtimespec = vap->va_mtime;
780 sb->st_ctimespec = vap->va_ctime;
781 sb->st_birthtimespec = vap->va_birthtime;
784 * According to www.opengroup.org, the meaning of st_blksize is
785 * "a filesystem-specific preferred I/O block size for this
786 * object. In some filesystem types, this may vary from file
788 * Default to PAGE_SIZE after much discussion.
789 * XXX: min(PAGE_SIZE, vp->v_bufobj.bo_bsize) may be more correct.
792 sb->st_blksize = PAGE_SIZE;
794 sb->st_flags = vap->va_flags;
795 if (priv_check(td, PRIV_VFS_GENERATION))
798 sb->st_gen = vap->va_gen;
800 sb->st_blocks = vap->va_bytes / S_BLKSIZE;
805 * File table vnode ioctl routine.
808 vn_ioctl(fp, com, data, active_cred, td)
812 struct ucred *active_cred;
815 struct vnode *vp = fp->f_vnode;
820 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
822 switch (vp->v_type) {
825 if (com == FIONREAD) {
826 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
827 error = VOP_GETATTR(vp, &vattr, active_cred);
830 *(int *)data = vattr.va_size - fp->f_offset;
832 if (com == FIONBIO || com == FIOASYNC) /* XXX */
835 error = VOP_IOCTL(vp, com, data, fp->f_flag,
842 VFS_UNLOCK_GIANT(vfslocked);
847 * File table vnode poll routine.
850 vn_poll(fp, events, active_cred, td)
853 struct ucred *active_cred;
861 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
863 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
864 error = mac_vnode_check_poll(active_cred, fp->f_cred, vp);
869 error = VOP_POLL(vp, events, fp->f_cred, td);
870 VFS_UNLOCK_GIANT(vfslocked);
875 * Acquire the requested lock and then check for validity. LK_RETRY
876 * permits vn_lock to return doomed vnodes.
879 _vn_lock(struct vnode *vp, int flags, char *file, int line)
883 VNASSERT((flags & LK_TYPE_MASK) != 0, vp,
884 ("vn_lock called with no locktype."));
886 #ifdef DEBUG_VFS_LOCKS
887 KASSERT(vp->v_holdcnt != 0,
888 ("vn_lock %p: zero hold count", vp));
890 error = VOP_LOCK1(vp, flags, file, line);
891 flags &= ~LK_INTERLOCK; /* Interlock is always dropped. */
892 KASSERT((flags & LK_RETRY) == 0 || error == 0,
893 ("LK_RETRY set with incompatible flags (0x%x) or an error occured (%d)",
896 * Callers specify LK_RETRY if they wish to get dead vnodes.
897 * If RETRY is not set, we return ENOENT instead.
899 if (error == 0 && vp->v_iflag & VI_DOOMED &&
900 (flags & LK_RETRY) == 0) {
905 } while (flags & LK_RETRY && error != 0);
910 * File table vnode close routine.
924 vfslocked = VFS_LOCK_GIANT(vp->v_mount);
925 if (fp->f_type == DTYPE_VNODE && fp->f_flag & FHASLOCK) {
926 lf.l_whence = SEEK_SET;
930 (void) VOP_ADVLOCK(vp, fp, F_UNLCK, &lf, F_FLOCK);
933 fp->f_ops = &badfileops;
935 error = vn_close(vp, fp->f_flag, fp->f_cred, td);
936 VFS_UNLOCK_GIANT(vfslocked);
941 * Preparing to start a filesystem write operation. If the operation is
942 * permitted, then we bump the count of operations in progress and
943 * proceed. If a suspend request is in progress, we wait until the
944 * suspension is over, and then proceed.
947 vn_start_write(vp, mpp, flags)
957 * If a vnode is provided, get and return the mount point that
958 * to which it will write.
961 if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
963 if (error != EOPNOTSUPP)
968 if ((mp = *mpp) == NULL)
972 * VOP_GETWRITEMOUNT() returns with the mp refcount held through
974 * As long as a vnode is not provided we need to acquire a
975 * refcount for the provided mountpoint too, in order to
976 * emulate a vfs_ref().
983 * Check on status of suspension.
985 if ((curthread->td_pflags & TDP_IGNSUSP) == 0 ||
986 mp->mnt_susp_owner != curthread) {
987 while ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
988 if (flags & V_NOWAIT) {
992 error = msleep(&mp->mnt_flag, MNT_MTX(mp),
993 (PUSER - 1) | (flags & PCATCH), "suspfs", 0);
998 if (flags & V_XSLEEP)
1000 mp->mnt_writeopcount++;
1008 * Secondary suspension. Used by operations such as vop_inactive
1009 * routines that are needed by the higher level functions. These
1010 * are allowed to proceed until all the higher level functions have
1011 * completed (indicated by mnt_writeopcount dropping to zero). At that
1012 * time, these operations are halted until the suspension is over.
1015 vn_start_secondary_write(vp, mpp, flags)
1025 if ((error = VOP_GETWRITEMOUNT(vp, mpp)) != 0) {
1027 if (error != EOPNOTSUPP)
1033 * If we are not suspended or have not yet reached suspended
1034 * mode, then let the operation proceed.
1036 if ((mp = *mpp) == NULL)
1040 * VOP_GETWRITEMOUNT() returns with the mp refcount held through
1042 * As long as a vnode is not provided we need to acquire a
1043 * refcount for the provided mountpoint too, in order to
1044 * emulate a vfs_ref().
1049 if ((mp->mnt_kern_flag & (MNTK_SUSPENDED | MNTK_SUSPEND2)) == 0) {
1050 mp->mnt_secondary_writes++;
1051 mp->mnt_secondary_accwrites++;
1056 if (flags & V_NOWAIT) {
1059 return (EWOULDBLOCK);
1062 * Wait for the suspension to finish.
1064 error = msleep(&mp->mnt_flag, MNT_MTX(mp),
1065 (PUSER - 1) | (flags & PCATCH) | PDROP, "suspfs", 0);
1073 * Filesystem write operation has completed. If we are suspending and this
1074 * operation is the last one, notify the suspender that the suspension is
1078 vn_finished_write(mp)
1084 mp->mnt_writeopcount--;
1085 if (mp->mnt_writeopcount < 0)
1086 panic("vn_finished_write: neg cnt");
1087 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 &&
1088 mp->mnt_writeopcount <= 0)
1089 wakeup(&mp->mnt_writeopcount);
1095 * Filesystem secondary write operation has completed. If we are
1096 * suspending and this operation is the last one, notify the suspender
1097 * that the suspension is now in effect.
1100 vn_finished_secondary_write(mp)
1106 mp->mnt_secondary_writes--;
1107 if (mp->mnt_secondary_writes < 0)
1108 panic("vn_finished_secondary_write: neg cnt");
1109 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0 &&
1110 mp->mnt_secondary_writes <= 0)
1111 wakeup(&mp->mnt_secondary_writes);
1118 * Request a filesystem to suspend write operations.
1121 vfs_write_suspend(mp)
1127 if (mp->mnt_susp_owner == curthread) {
1131 while (mp->mnt_kern_flag & MNTK_SUSPEND)
1132 msleep(&mp->mnt_flag, MNT_MTX(mp), PUSER - 1, "wsuspfs", 0);
1133 mp->mnt_kern_flag |= MNTK_SUSPEND;
1134 mp->mnt_susp_owner = curthread;
1135 if (mp->mnt_writeopcount > 0)
1136 (void) msleep(&mp->mnt_writeopcount,
1137 MNT_MTX(mp), (PUSER - 1)|PDROP, "suspwt", 0);
1140 if ((error = VFS_SYNC(mp, MNT_SUSPEND)) != 0)
1141 vfs_write_resume(mp);
1146 * Request a filesystem to resume write operations.
1149 vfs_write_resume(mp)
1154 if ((mp->mnt_kern_flag & MNTK_SUSPEND) != 0) {
1155 KASSERT(mp->mnt_susp_owner == curthread, ("mnt_susp_owner"));
1156 mp->mnt_kern_flag &= ~(MNTK_SUSPEND | MNTK_SUSPEND2 |
1158 mp->mnt_susp_owner = NULL;
1159 wakeup(&mp->mnt_writeopcount);
1160 wakeup(&mp->mnt_flag);
1161 curthread->td_pflags &= ~TDP_IGNSUSP;
1169 * Implement kqueues for files by translating it to vnode operation.
1172 vn_kqfilter(struct file *fp, struct knote *kn)
1177 vfslocked = VFS_LOCK_GIANT(fp->f_vnode->v_mount);
1178 error = VOP_KQFILTER(fp->f_vnode, kn);
1179 VFS_UNLOCK_GIANT(vfslocked);
1185 * Simplified in-kernel wrapper calls for extended attribute access.
1186 * Both calls pass in a NULL credential, authorizing as "kernel" access.
1187 * Set IO_NODELOCKED in ioflg if the vnode is already locked.
1190 vn_extattr_get(struct vnode *vp, int ioflg, int attrnamespace,
1191 const char *attrname, int *buflen, char *buf, struct thread *td)
1197 iov.iov_len = *buflen;
1200 auio.uio_iov = &iov;
1201 auio.uio_iovcnt = 1;
1202 auio.uio_rw = UIO_READ;
1203 auio.uio_segflg = UIO_SYSSPACE;
1205 auio.uio_offset = 0;
1206 auio.uio_resid = *buflen;
1208 if ((ioflg & IO_NODELOCKED) == 0)
1209 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1211 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
1213 /* authorize attribute retrieval as kernel */
1214 error = VOP_GETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, NULL,
1217 if ((ioflg & IO_NODELOCKED) == 0)
1221 *buflen = *buflen - auio.uio_resid;
1228 * XXX failure mode if partially written?
1231 vn_extattr_set(struct vnode *vp, int ioflg, int attrnamespace,
1232 const char *attrname, int buflen, char *buf, struct thread *td)
1239 iov.iov_len = buflen;
1242 auio.uio_iov = &iov;
1243 auio.uio_iovcnt = 1;
1244 auio.uio_rw = UIO_WRITE;
1245 auio.uio_segflg = UIO_SYSSPACE;
1247 auio.uio_offset = 0;
1248 auio.uio_resid = buflen;
1250 if ((ioflg & IO_NODELOCKED) == 0) {
1251 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
1253 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1256 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
1258 /* authorize attribute setting as kernel */
1259 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, &auio, NULL, td);
1261 if ((ioflg & IO_NODELOCKED) == 0) {
1262 vn_finished_write(mp);
1270 vn_extattr_rm(struct vnode *vp, int ioflg, int attrnamespace,
1271 const char *attrname, struct thread *td)
1276 if ((ioflg & IO_NODELOCKED) == 0) {
1277 if ((error = vn_start_write(vp, &mp, V_WAIT)) != 0)
1279 vn_lock(vp, LK_EXCLUSIVE | LK_RETRY);
1282 ASSERT_VOP_LOCKED(vp, "IO_NODELOCKED with no vp lock held");
1284 /* authorize attribute removal as kernel */
1285 error = VOP_DELETEEXTATTR(vp, attrnamespace, attrname, NULL, td);
1286 if (error == EOPNOTSUPP)
1287 error = VOP_SETEXTATTR(vp, attrnamespace, attrname, NULL,
1290 if ((ioflg & IO_NODELOCKED) == 0) {
1291 vn_finished_write(mp);
1299 vn_vget_ino(struct vnode *vp, ino_t ino, int lkflags, struct vnode **rvp)
1305 ltype = VOP_ISLOCKED(vp);
1306 KASSERT(ltype == LK_EXCLUSIVE || ltype == LK_SHARED,
1307 ("vn_vget_ino: vp not locked"));
1308 error = vfs_busy(mp, MBF_NOWAIT);
1312 error = vfs_busy(mp, 0);
1313 vn_lock(vp, ltype | LK_RETRY);
1317 if (vp->v_iflag & VI_DOOMED) {
1323 error = VFS_VGET(mp, ino, lkflags, rvp);
1325 vn_lock(vp, ltype | LK_RETRY);
1326 if (vp->v_iflag & VI_DOOMED) {