vref9freebsd
Increment the use count for a vnode
Part of VREF(9freebsd).
Usage
#include <sys/param.h>
#include <sys/vnode.h>
void
vref(struct vnode *vp);
void
vrefl(struct vnode *vp);
Overview
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.
Releases
9 releases since Debian 5.0 (Lenny); the text changed 6 times.