xref: /freebsd/share/man/man9/vhold.9 (revision 571dba6ec9f25ecf7582dc2192daf1ceea70065f)
121642577SAlfred Perlstein.\"
221642577SAlfred Perlstein.\" Copyright (C) 2001 Chad David <davidc@acns.ab.ca>. All rights reserved.
321642577SAlfred Perlstein.\"
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2821642577SAlfred Perlstein.\"
2921642577SAlfred Perlstein.Dd November 21, 2001
3021642577SAlfred Perlstein.Dt VHOLD 9
3121642577SAlfred Perlstein.Os
3221642577SAlfred Perlstein.Sh NAME
331f620c2eSRuslan Ermilov.Nm vhold , vdrop
341f620c2eSRuslan Ermilov.Nd "acquire/release a hold on a vnode"
3521642577SAlfred Perlstein.Sh SYNOPSIS
3621642577SAlfred Perlstein.In sys/param.h
3721642577SAlfred Perlstein.In sys/vnode.h
3821642577SAlfred Perlstein.Ft void
3921642577SAlfred Perlstein.Fn vhold "struct vnode *vp"
4021642577SAlfred Perlstein.Ft void
4121642577SAlfred Perlstein.Fn vdrop "struct vnode *vp"
4221642577SAlfred Perlstein.Sh DESCRIPTION
4321642577SAlfred PerlsteinThe
4421642577SAlfred Perlstein.Fn vhold
451f620c2eSRuslan Ermilovfunction increments the
461f620c2eSRuslan Ermilov.Va v_holdcnt
471f620c2eSRuslan Ermilovof the given vnode.
481f620c2eSRuslan ErmilovIf the vnode has already been added to the free list and is still referenced,
4921642577SAlfred Perlsteinit will be removed.
5021642577SAlfred Perlstein.Pp
5121642577SAlfred PerlsteinThe
5221642577SAlfred Perlstein.Fn vdrop
531f620c2eSRuslan Ermilovfunction decrements the
541f620c2eSRuslan Ermilov.Va v_holdcnt
551f620c2eSRuslan Ermilovof the vnode.
561f620c2eSRuslan ErmilovIf the holdcount is less than or equal zero prior to calling
571f620c2eSRuslan Ermilov.Fn vdrop ,
5821642577SAlfred Perlsteinthe system will panic.
591f620c2eSRuslan ErmilovIf the vnode is no longer referenced, it will freed.
6021642577SAlfred Perlstein.Sh SEE ALSO
611f620c2eSRuslan Ermilov.Xr vbusy 9 ,
621f620c2eSRuslan Ermilov.Xr vfree 9
6321642577SAlfred Perlstein.Sh AUTHORS
64571dba6eSHiten PandyaThis manual page was written by
6521642577SAlfred Perlstein.An Chad David Aq davidc@acns.ab.ca .
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