Function vm_page_object_remove

freebsd/vm/vm_page.c:1611–1646

* Do the work to remove a page from its object. The caller is responsible for * updating the page's fields to reflect this removal. */

 * updating the page's fields to reflect this removal.
 */
static void
vm_page_object_remove(vm_page_t m)
{
	vm_object_t object;
	vm_page_t mrem;

	vm_page_assert_xbusied(m);
	object = m->object;
	VM_OBJECT_ASSERT_WLOCKED(object);
	KASSERT((m->ref_count & VPRC_OBJREF) != 0,
	    ("page %p is missing its object ref", m));

	/* Deferred free of swap space. */
	if ((m->a.flags & PGA_SWAP_FREE) != 0)
		vm_pager_page_unswapped(m);

	m->object = NULL;
	mrem = vm_radix_remove(&object->rtree, m->pindex);
	KASSERT(mrem == m, ("removed page %p, expected page %p", mrem, m));

	/*
	 * Now remove from the object's list of backed pages.
	 */
	TAILQ_REMOVE(&object->memq, m, listq);

	/*
	 * And show that the object has one fewer resident page.
	 */
	object->resident_page_count--;

	/*
	 * The vnode may now be recycled.
	 */
	if (object->resident_page_count == 0 && object->type == OBJT_VNODE)
		vdrop(object->handle);
}

/*
 *	vm_page_remove: