/*
* Like vn_rele() except if we are going to call VOP_INACTIVE() then do it
* asynchronously using a taskq. This can avoid deadlocks caused by re-entering
* the file system as a result of releasing the vnode. Note, file systems
* already have to handle the race where the vnode is incremented before the
* inactive routine is called and does its locking.
*
* Warning: Excessive use of this routine can lead to performance problems.
* This is because taskqs throttle back allocation if too many are created.
*/
void
vn_rele_async(vnode_t *vp, taskq_t *taskq)
{
VERIFY(vp->v_count > 0);
VI_LOCK(vp);
if (vp->v_count == 1 && !(vp->v_iflag & VI_DOINGINACT)) {
VI_UNLOCK(vp);
VERIFY(taskq_dispatch((taskq_t *)taskq,
(task_func_t *)vn_rele_inactive, vp, TQ_SLEEP) != 0);
return;
}
vp->v_usecount--;
vdropl(vp);
}
static int
ufs_lookup_upgrade_lock(struct vnode *vp)
{
int error;
ASSERT_VOP_LOCKED(vp, __FUNCTION__);
if (VOP_ISLOCKED(vp) == LK_EXCLUSIVE)
return (0);
error = 0;
/*
* Upgrade vnode lock, since getinoquota()
* requires exclusive lock to modify inode.
*/
vhold(vp);
vn_lock(vp, LK_UPGRADE | LK_RETRY);
VI_LOCK(vp);
if (vp->v_iflag & VI_DOOMED)
error = ENOENT;
vdropl(vp);
return (error);
}
