1 /*
2 * Copyright (c) 2010 by The DragonFly Project and Samuel J. Greear.
3 * All rights reserved.
4 *
5 * This code is derived from software contributed to The DragonFly Project
6 * by Samuel J. Greear <sjg@thesjg.com>
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 *
12 * 1. Redistributions of source code must retain the above copyright
13 * notice, this list of conditions and the following disclaimer.
14 * 2. Redistributions in binary form must reproduce the above copyright
15 * notice, this list of conditions and the following disclaimer in
16 * the documentation and/or other materials provided with the
17 * distribution.
18 * 3. Neither the name of The DragonFly Project nor the names of its
19 * contributors may be used to endorse or promote products derived
20 * from this software without specific, prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
23 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
24 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
25 * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
26 * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
27 * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
28 * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
29 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
30 * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
31 * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
32 * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
33 * SUCH DAMAGE.
34 */
35
36 #ifndef _CPU_LWBUF_H_
37 #define _CPU_LWBUF_H_
38
39 #ifndef _SYS_TYPES_H_
40 #include <sys/types.h>
41 #endif
42 #ifndef _SYS_GLOBALDATA_H_
43 #include <sys/globaldata.h>
44 #endif
45 #ifndef _VM_PMAP_H_
46 #include <vm/pmap.h>
47 #endif
48 #ifndef _VM_VM_PAGE_H_
49 #include <vm/vm_page.h>
50 #endif
51 #include <machine/atomic.h>
52 #ifndef _MACHINE_VMPARAM_H_
53 #include <machine/vmparam.h>
54 #endif
55
56 #if !defined(_KERNEL) && !defined(_KERNEL_STRUCTURES)
57 #error "This file should not be included by userland programs."
58 #endif
59
60 struct lwbuf {
61 vm_page_t m; /* currently mapped page */
62 vm_offset_t kva; /* va of mapping */
63 };
64
65 static __inline vm_page_t
lwbuf_page(struct lwbuf * lwb)66 lwbuf_page(struct lwbuf *lwb)
67 {
68 return (lwb->m);
69 }
70
71 static __inline vm_offset_t
lwbuf_kva(struct lwbuf * lwb)72 lwbuf_kva(struct lwbuf *lwb)
73 {
74 return (lwb->kva);
75 }
76
77 static __inline struct lwbuf *
lwbuf_alloc(vm_page_t m,struct lwbuf * lwb_cache)78 lwbuf_alloc(vm_page_t m, struct lwbuf *lwb_cache)
79 {
80 struct lwbuf *lwb = lwb_cache;
81
82 lwb->m = m;
83 lwb->kva = PHYS_TO_DMAP(VM_PAGE_TO_PHYS(lwb->m));
84
85 return (lwb);
86 }
87
88 static __inline void
lwbuf_free(struct lwbuf * lwb)89 lwbuf_free(struct lwbuf *lwb)
90 {
91 lwb->m = NULL; /* safety */
92 }
93
94 #define lwbuf_set_global(lwb)
95
96 /* tell the kernel that lwbufs are cheap */
97 #define LWBUF_IS_OPTIMAL
98
99 #if defined(_KERNEL)
100
101 #endif
102
103 #endif /* !_CPU_LWBUF_H_ */
104