xref: /freebsd-src/sys/riscv/include/sf_buf.h (revision 95ee2897e98f5d444f26ed2334cc7c439f9c16c6)
1*8d7e7a98SRuslan Bukin /*-
2*8d7e7a98SRuslan Bukin  * Copyright (c) 2003, 2005 Alan L. Cox <alc@cs.rice.edu>
3*8d7e7a98SRuslan Bukin  * All rights reserved.
4*8d7e7a98SRuslan Bukin  *
5*8d7e7a98SRuslan Bukin  * Redistribution and use in source and binary forms, with or without
6*8d7e7a98SRuslan Bukin  * modification, are permitted provided that the following conditions
7*8d7e7a98SRuslan Bukin  * are met:
8*8d7e7a98SRuslan Bukin  * 1. Redistributions of source code must retain the above copyright
9*8d7e7a98SRuslan Bukin  *    notice, this list of conditions and the following disclaimer.
10*8d7e7a98SRuslan Bukin  * 2. Redistributions in binary form must reproduce the above copyright
11*8d7e7a98SRuslan Bukin  *    notice, this list of conditions and the following disclaimer in the
12*8d7e7a98SRuslan Bukin  *    documentation and/or other materials provided with the distribution.
13*8d7e7a98SRuslan Bukin  *
14*8d7e7a98SRuslan Bukin  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15*8d7e7a98SRuslan Bukin  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16*8d7e7a98SRuslan Bukin  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17*8d7e7a98SRuslan Bukin  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18*8d7e7a98SRuslan Bukin  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19*8d7e7a98SRuslan Bukin  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20*8d7e7a98SRuslan Bukin  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21*8d7e7a98SRuslan Bukin  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22*8d7e7a98SRuslan Bukin  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23*8d7e7a98SRuslan Bukin  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24*8d7e7a98SRuslan Bukin  * SUCH DAMAGE.
25*8d7e7a98SRuslan Bukin  */
26*8d7e7a98SRuslan Bukin 
27*8d7e7a98SRuslan Bukin #ifndef _MACHINE_SF_BUF_H_
28*8d7e7a98SRuslan Bukin #define	_MACHINE_SF_BUF_H_
29*8d7e7a98SRuslan Bukin 
30*8d7e7a98SRuslan Bukin /*
31*8d7e7a98SRuslan Bukin  * On this machine, the only purpose for which sf_buf is used is to implement
32*8d7e7a98SRuslan Bukin  * an opaque pointer required by the machine-independent parts of the kernel.
33*8d7e7a98SRuslan Bukin  * That pointer references the vm_page that is "mapped" by the sf_buf.  The
34*8d7e7a98SRuslan Bukin  * actual mapping is provided by the direct virtual-to-physical mapping.
35*8d7e7a98SRuslan Bukin  */
36*8d7e7a98SRuslan Bukin static inline vm_offset_t
sf_buf_kva(struct sf_buf * sf)37*8d7e7a98SRuslan Bukin sf_buf_kva(struct sf_buf *sf)
38*8d7e7a98SRuslan Bukin {
39*8d7e7a98SRuslan Bukin 
40*8d7e7a98SRuslan Bukin 	return (PHYS_TO_DMAP(VM_PAGE_TO_PHYS((vm_page_t)sf)));
41*8d7e7a98SRuslan Bukin }
42*8d7e7a98SRuslan Bukin 
43*8d7e7a98SRuslan Bukin static inline vm_page_t
sf_buf_page(struct sf_buf * sf)44*8d7e7a98SRuslan Bukin sf_buf_page(struct sf_buf *sf)
45*8d7e7a98SRuslan Bukin {
46*8d7e7a98SRuslan Bukin 
47*8d7e7a98SRuslan Bukin 	return ((vm_page_t)sf);
48*8d7e7a98SRuslan Bukin }
49*8d7e7a98SRuslan Bukin #endif /* !_MACHINE_SF_BUF_H_ */
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