Manpages

VREF(9) BSD Kernel Developer’s Manual VREF(9)

NAME

vref, vrefl — increment the use count for a vnode

SYNOPSIS

#include <sys/param.h>
#include <sys/vnode.h>

void

vref(struct vnode *vp);

void

vrefl(struct vnode *vp);

DESCRIPTION

Increment the v_usecount field of a vnode.

vp

the vnode to increment

Each vnode maintains a reference count of how many parts of the system are using the vnode. This allows the system to detect when a vnode is no longer being used and can be safely recycled for a different file.

Any code in the system which is using a vnode (e.g. during the operation of some algorithm or to store in a data structure) should call vref() or vrefl().

vref() locks the vnode interlock while vrefl() expects the interlock to already be held.

SEE ALSO

vget(9), vnode(9), vput(9), vrefcnt(9), vrele(9)

AUTHORS

This manual page was written by Doug Rabson.

BSD January 18, 2016 BSD