xref: /freebsd/share/man/man9/vfs_busy.9 (revision 3141712daac026e09aedf0d420cb0f19d6dfb80b)
18981fef8SAlfred Perlstein.\"
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288981fef8SAlfred Perlstein.\"
29*3141712dSJaakko Heinonen.Dd June 14, 2010
308981fef8SAlfred Perlstein.Dt VFS_BUSY 9
318981fef8SAlfred Perlstein.Os
328981fef8SAlfred Perlstein.Sh NAME
338981fef8SAlfred Perlstein.Nm vfs_busy
3423789024SRuslan Ermilov.Nd "marks a mount point as busy"
358981fef8SAlfred Perlstein.Sh SYNOPSIS
3623789024SRuslan Ermilov.In sys/param.h
3723789024SRuslan Ermilov.In sys/mount.h
388981fef8SAlfred Perlstein.Ft int
391efbe1a4SAttilio Rao.Fn vfs_busy "struct mount *mp" "int flags"
408981fef8SAlfred Perlstein.Sh DESCRIPTION
418981fef8SAlfred PerlsteinThe
4223789024SRuslan Ermilov.Fn vfs_busy
43*3141712dSJaakko Heinonenfunction marks a mount point as busy by incrementing
44*3141712dSJaakko Heinonenthe reference count of a mount point.
45034709cbSRuslan ErmilovIt also delays unmounting by sleeping on
46034709cbSRuslan Ermilov.Fa mp
47034709cbSRuslan Ermilovif the
4823789024SRuslan Ermilov.Dv MNTK_UNMOUNT
4923789024SRuslan Ermilovflag is set in
5023789024SRuslan Ermilov.Fa mp->mnt_kern_flag
5123789024SRuslan Ermilovand the
52*3141712dSJaakko Heinonen.Dv MBF_NOWAIT
5323789024SRuslan Ermilovflag is
5423789024SRuslan Ermilov.Em not
5523789024SRuslan Ermilovset.
568981fef8SAlfred Perlstein.Pp
578981fef8SAlfred PerlsteinIts arguments are:
581efbe1a4SAttilio Rao.Bl -tag -width ".Fa flags"
5923789024SRuslan Ermilov.It Fa mp
608981fef8SAlfred PerlsteinThe mount point to busy.
6123789024SRuslan Ermilov.It Fa flags
62034709cbSRuslan ErmilovFlags controlling how
63034709cbSRuslan Ermilov.Fn vfs_busy
64034709cbSRuslan Ermilovshould act.
651efbe1a4SAttilio Rao.Bl -tag -width ".Dv MBF_MNTLSTLOCK"
661efbe1a4SAttilio Rao.It Dv MBF_NOWAIT
6723789024SRuslan Ermilovdo not sleep if
6823789024SRuslan Ermilov.Dv MNTK_UNMOUNT
6923789024SRuslan Ermilovis set.
701efbe1a4SAttilio Rao.It Dv MBF_MNTLSTLOCK
711efbe1a4SAttilio Raodrop the mountlist_mtx in the critical path.
7223789024SRuslan Ermilov.El
738981fef8SAlfred Perlstein.El
748981fef8SAlfred Perlstein.Sh RETURN VALUES
7523789024SRuslan ErmilovA 0 value is returned on success.
7623789024SRuslan ErmilovIf the mount point is being
77*3141712dSJaakko Heinonenunmounted and MBF_NOWAIT flag is specified
7823789024SRuslan Ermilov.Er ENOENT
79*3141712dSJaakko Heinonenwill be returned.
808981fef8SAlfred Perlstein.Sh ERRORS
8123789024SRuslan Ermilov.Bl -tag -width Er
8223789024SRuslan Ermilov.It Bq Er ENOENT
8323789024SRuslan ErmilovThe mount point is being unmounted
8423789024SRuslan Ermilov.Dv ( MNTK_UNMOUNT
8523789024SRuslan Ermilovis set).
868981fef8SAlfred Perlstein.El
878981fef8SAlfred Perlstein.Sh AUTHORS
8809356c84SHiten PandyaThis manual page was written by
89034709cbSRuslan Ermilov.An Chad David Aq davidc@acns.ab.ca .
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