xref: /dragonfly/sys/sys/sfbuf.h (revision 7d3e9a5b)
1 /*
2  * Copyright (c) 2003 Alan L. Cox <alc@cs.rice.edu>.  All rights reserved.
3  * Copyright (c) 1998 David Greenman.  All rights reserved.
4  *
5  * Redistribution and use in source and binary forms, with or without
6  * modification, are permitted provided that the following conditions
7  * are met:
8  * 1. Redistributions of source code must retain the above copyright
9  *    notice, this list of conditions and the following disclaimer.
10  * 2. Redistributions in binary form must reproduce the above copyright
11  *    notice, this list of conditions and the following disclaimer in the
12  *    documentation and/or other materials provided with the distribution.
13  *
14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
24  * SUCH DAMAGE.
25  */
26 
27 #ifndef _SYS_SFBUF_H_
28 #define _SYS_SFBUF_H_
29 
30 #ifndef _SYS_TYPES_H_
31 #include <sys/types.h>
32 #endif
33 #ifndef _CPU_LWBUF_H_
34 #include <cpu/lwbuf.h>
35 #endif
36 
37 #if !defined(_KERNEL) && !defined(_KERNEL_STRUCTURES)
38 #error "This file should not be included by userland programs."
39 #endif
40 
41 struct sf_buf {
42 	struct lwbuf	*lwbuf;	/* lightweight buffer */
43 	u_int		ref;	/* ref count */
44 	struct lwbuf	lwbuf_cache;
45 };
46 
47 #define sf_buf_kva(sf)	(lwbuf_kva((sf)->lwbuf))
48 #define sf_buf_page(sf)	(lwbuf_page((sf)->lwbuf))
49 
50 
51 #if defined(_KERNEL)
52 
53 struct sf_buf  *sf_buf_alloc(struct vm_page *);
54 void		sf_buf_ref(void *);
55 int		sf_buf_free(void *);
56 
57 #endif
58 
59 #endif /* !_SYS_SFBUF_H_ */
60