|VRELE(9)||Kernel Developer's Manual||VRELE(9)|
DESCRIPTION¶Decrement the v_usecount field of a vnode.
- the vnode to decrement
vrele() function takes an unlocked
vnode and returns with the vnode unlocked.
vput() function should be given a
locked vnode as argument, the vnode is unlocked after the function returned.
vput() is operationally equivalent to calling
VOP_UNLOCK(9) followed by vrele(9), with
vunref() function takes a locked vnode
as argument, and returns with the vnode locked.
Any code in the system which signified its use of a vnode by usecount should call one of the listed function to decrement use counter. If the v_usecount field of the non-doomed vnode reaches zero, then it will be inactivated and placed on the free list.
vrele() function may lock the vnode.
All three functions may sleep.
The hold count for the vnode is always greater or equal to the usecount. Non-forced unmount fails when mount point owns a vnode that has non-zero usecount, see vflush(9).
SEE ALSO¶vget(9), vnode(9), vref(9), vrefcnt(9)
AUTHORS¶This manual page was written by Doug Rabson and
|February 24, 2016||Linux 4.19.0-6-amd64|