1 /*- 2 * SPDX-License-Identifier: BSD-2-Clause 3 * 4 * Copyright (c) 2003, 2005 Alan L. Cox <alc@cs.rice.edu> 5 * All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND 17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 19 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE 20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 26 * SUCH DAMAGE. 27 * 28 * $FreeBSD$ 29 */ 30 31 #ifndef _MACHINE_SF_BUF_H_ 32 #define _MACHINE_SF_BUF_H_ 33 34 #ifdef __amd64__ 35 /* 36 * On this machine, the only purpose for which sf_buf is used is to implement 37 * an opaque pointer required by the machine-independent parts of the kernel. 38 * That pointer references the vm_page that is "mapped" by the sf_buf. The 39 * actual mapping is provided by the direct virtual-to-physical mapping. 40 */ 41 static inline vm_offset_t 42 sf_buf_kva(struct sf_buf *sf) 43 { 44 45 return (PHYS_TO_DMAP(VM_PAGE_TO_PHYS((vm_page_t)sf))); 46 } 47 48 static inline vm_page_t 49 sf_buf_page(struct sf_buf *sf) 50 { 51 52 return ((vm_page_t)sf); 53 } 54 #endif /* __amd64__ */ 55 #endif /* !_MACHINE_SF_BUF_H_ */ 56