1 /*
2 * (MPSAFE)
3 *
4 * Copyright (c) 2000 Peter Wemm
5 *
6 * Redistribution and use in source and binary forms, with or without
7 * modification, are permitted provided that the following conditions
8 * are met:
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
11 * 2. Redistributions in binary form must reproduce the above copyright
12 * notice, this list of conditions and the following disclaimer in the
13 * documentation and/or other materials provided with the distribution.
14 *
15 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND
16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE
19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
25 * SUCH DAMAGE.
26 *
27 * $FreeBSD: src/sys/vm/phys_pager.c,v 1.3.2.3 2000/12/17 02:05:41 alfred Exp $
28 */
29 #include <sys/param.h>
30 #include <sys/systm.h>
31 #include <sys/linker_set.h>
32 #include <sys/conf.h>
33 #include <sys/mman.h>
34 #include <sys/sysctl.h>
35
36 #include <vm/vm.h>
37 #include <vm/vm_object.h>
38 #include <vm/vm_page.h>
39 #include <vm/vm_pager.h>
40 #include <vm/vm_zone.h>
41
42 #include <vm/vm_page2.h>
43
44 static pgo_dealloc_t phys_pager_dealloc;
45 static pgo_getpage_t phys_pager_getpage;
46 static pgo_putpages_t phys_pager_putpages;
47 static pgo_haspage_t phys_pager_haspage;
48
49 struct pagerops physpagerops = {
50 .pgo_dealloc = phys_pager_dealloc,
51 .pgo_getpage = phys_pager_getpage,
52 .pgo_putpages = phys_pager_putpages,
53 .pgo_haspage = phys_pager_haspage
54 };
55
56 /*
57 * No requirements.
58 */
59 vm_object_t
phys_pager_alloc(void * handle,off_t size,vm_prot_t prot,off_t foff)60 phys_pager_alloc(void *handle, off_t size, vm_prot_t prot, off_t foff)
61 {
62 vm_object_t object;
63
64 /*
65 * Offset should be page aligned.
66 */
67 if (foff & PAGE_MASK)
68 return (NULL);
69
70 size = round_page64(size);
71
72 KKASSERT(handle == NULL);
73 object = vm_object_allocate(OBJT_PHYS, OFF_TO_IDX(foff + size));
74
75 return (object);
76 }
77
78 /*
79 * No requirements.
80 */
81 static void
phys_pager_dealloc(vm_object_t object)82 phys_pager_dealloc(vm_object_t object)
83 {
84 KKASSERT(object->handle == NULL);
85 KKASSERT(object->swblock_count == 0);
86 }
87
88 /*
89 * No requirements.
90 */
91 static int
phys_pager_getpage(vm_object_t object,vm_pindex_t pindex,vm_page_t * mpp,int seqaccess)92 phys_pager_getpage(vm_object_t object, vm_pindex_t pindex,
93 vm_page_t *mpp, int seqaccess)
94 {
95 vm_page_t m = *mpp;
96
97 vm_page_zero_fill(m);
98 /* Switch off pv_entries */
99 vm_page_flag_set(m, PG_UNQUEUED);
100 m->valid = VM_PAGE_BITS_ALL;
101 m->dirty = VM_PAGE_BITS_ALL;
102
103 return (VM_PAGER_OK);
104 }
105
106 /*
107 * No requirements.
108 */
109 static void
phys_pager_putpages(vm_object_t object,vm_page_t * m,int count,int flags,int * rtvals)110 phys_pager_putpages(vm_object_t object, vm_page_t *m, int count,
111 int flags, int *rtvals)
112 {
113
114 panic("phys_pager_putpage called");
115 }
116
117 /*
118 * Implement a pretty aggressive clustered getpages strategy. Hint that
119 * everything in an entire 4MB window should be prefaulted at once.
120 *
121 * XXX 4MB (1024 slots per page table page) is convenient for x86,
122 * but may not be for other arches.
123 */
124 #ifndef PHYSCLUSTER
125 #define PHYSCLUSTER 1024
126 #endif
127
128 /*
129 * No requirements.
130 */
131 static boolean_t
phys_pager_haspage(vm_object_t object,vm_pindex_t pindex)132 phys_pager_haspage(vm_object_t object, vm_pindex_t pindex)
133 {
134 return (TRUE);
135 }
136