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619edcce KM |
1 | /* |
2 | * Copyright (c) 1990 University of Utah. | |
3 | * Copyright (c) 1991 The Regents of the University of California. | |
4 | * All rights reserved. | |
5 | * | |
6 | * This code is derived from software contributed to Berkeley by | |
7 | * the Systems Programming Group of the University of Utah Computer | |
8 | * Science Department. | |
9 | * | |
10 | * %sccs.include.redist.c% | |
11 | * | |
a9966b2d | 12 | * @(#)device_pager.c 7.5 (Berkeley) %G% |
619edcce KM |
13 | */ |
14 | ||
15 | /* | |
16 | * Page to/from special files. | |
17 | */ | |
18 | ||
19 | #include "devpager.h" | |
20 | #if NDEVPAGER > 0 | |
21 | ||
22 | #include "param.h" | |
619edcce KM |
23 | #include "conf.h" |
24 | #include "mman.h" | |
25 | #include "malloc.h" | |
619edcce | 26 | |
ffe0d082 MK |
27 | #include "vm.h" |
28 | #include "vm_page.h" | |
29 | #include "vm_kern.h" | |
30 | #include "device_pager.h" | |
619edcce KM |
31 | |
32 | queue_head_t dev_pager_list; /* list of managed devices */ | |
33 | ||
34 | #ifdef DEBUG | |
35 | int dpagerdebug = 0; | |
36 | #define DDB_FOLLOW 0x01 | |
37 | #define DDB_INIT 0x02 | |
38 | #define DDB_ALLOC 0x04 | |
39 | #define DDB_FAIL 0x08 | |
40 | #endif | |
41 | ||
42 | void | |
43 | dev_pager_init() | |
44 | { | |
45 | #ifdef DEBUG | |
46 | if (dpagerdebug & DDB_FOLLOW) | |
47 | printf("dev_pager_init()\n"); | |
48 | #endif | |
49 | queue_init(&dev_pager_list); | |
50 | } | |
51 | ||
52 | vm_pager_t | |
53 | dev_pager_alloc(handle, size, prot) | |
54 | caddr_t handle; | |
55 | vm_size_t size; | |
56 | vm_prot_t prot; | |
57 | { | |
58 | dev_t dev; | |
59 | vm_pager_t pager; | |
60 | int (*mapfunc)(), nprot; | |
61 | register vm_object_t object; | |
62 | register vm_page_t page; | |
63 | register dev_pager_t devp; | |
64 | register int npages, off; | |
ffe0d082 | 65 | extern int nullop(), enodev(); |
619edcce KM |
66 | |
67 | ||
68 | #ifdef DEBUG | |
69 | if (dpagerdebug & DDB_FOLLOW) | |
70 | printf("dev_pager_alloc(%x, %x, %x)\n", handle, size, prot); | |
71 | #endif | |
72 | /* | |
73 | * Pageout to device, should never happen. | |
74 | */ | |
75 | if (handle == NULL) | |
76 | panic("dev_pager_alloc called"); | |
77 | ||
78 | /* | |
79 | * Look it up, creating as necessary | |
80 | */ | |
81 | pager = vm_pager_lookup(&dev_pager_list, handle); | |
ffe0d082 | 82 | if (pager == NULL) { |
619edcce KM |
83 | /* |
84 | * Validation. Make sure this device can be mapped | |
85 | * and that range to map is acceptible to device. | |
86 | */ | |
87 | dev = (dev_t)handle; | |
88 | mapfunc = cdevsw[major(dev)].d_mmap; | |
ffe0d082 MK |
89 | if (!mapfunc || mapfunc == enodev || mapfunc == nullop) |
90 | return(NULL); | |
619edcce KM |
91 | nprot = 0; |
92 | if (prot & VM_PROT_READ) | |
93 | nprot |= PROT_READ; | |
94 | if (prot & VM_PROT_WRITE) | |
95 | nprot |= PROT_WRITE; | |
96 | if (prot & VM_PROT_EXECUTE) | |
97 | nprot |= PROT_EXEC; | |
98 | npages = atop(round_page(size)); | |
99 | for (off = 0; npages--; off += PAGE_SIZE) | |
100 | if ((*mapfunc)(dev, off, nprot) == -1) | |
ffe0d082 | 101 | return(NULL); |
619edcce KM |
102 | /* |
103 | * Allocate and initialize pager structs | |
104 | */ | |
105 | pager = (vm_pager_t)malloc(sizeof *pager, M_VMPAGER, M_WAITOK); | |
ffe0d082 MK |
106 | if (pager == NULL) |
107 | return(NULL); | |
619edcce | 108 | devp = (dev_pager_t)malloc(sizeof *devp, M_VMPGDATA, M_WAITOK); |
ffe0d082 | 109 | if (devp == NULL) { |
619edcce | 110 | free((caddr_t)pager, M_VMPAGER); |
ffe0d082 | 111 | return(NULL); |
619edcce KM |
112 | } |
113 | devp->devp_dev = dev; | |
114 | devp->devp_npages = atop(round_page(size)); | |
115 | pager->pg_handle = handle; | |
116 | pager->pg_ops = &devicepagerops; | |
117 | pager->pg_type = PG_DEVICE; | |
118 | pager->pg_data = (caddr_t)devp; | |
119 | /* | |
120 | * Allocate object and vm_page structures to describe memory | |
121 | */ | |
122 | npages = devp->devp_npages; | |
123 | object = devp->devp_object = vm_object_allocate(ptoa(npages)); | |
124 | vm_object_enter(object, pager); | |
125 | vm_object_setpager(object, pager, (vm_offset_t)0, FALSE); | |
126 | devp->devp_pages = (vm_page_t) | |
127 | kmem_alloc(kernel_map, npages*sizeof(struct vm_page)); | |
128 | off = 0; | |
129 | for (page = devp->devp_pages; | |
130 | page < &devp->devp_pages[npages]; page++) { | |
131 | vm_object_lock(object); | |
269ac86e | 132 | VM_PAGE_INIT(page, object, off); |
619edcce KM |
133 | page->phys_addr = |
134 | pmap_phys_address((*mapfunc)(dev, off, nprot)); | |
135 | page->wire_count = 1; | |
136 | page->fictitious = TRUE; | |
137 | PAGE_WAKEUP(page); | |
138 | vm_object_unlock(object); | |
139 | off += PAGE_SIZE; | |
140 | } | |
141 | /* | |
142 | * Finally, put it on the managed list so other can find it. | |
143 | */ | |
144 | queue_enter(&dev_pager_list, devp, dev_pager_t, devp_list); | |
145 | #ifdef DEBUG | |
4c038ede | 146 | if (dpagerdebug & DDB_ALLOC) { |
619edcce KM |
147 | printf("dev_pager_alloc: pages %d@%x\n", |
148 | devp->devp_npages, devp->devp_pages); | |
4c038ede KM |
149 | printf("dev_pager_alloc: pager %x devp %x object %x\n", |
150 | pager, devp, object); | |
151 | vm_object_print(object, FALSE); | |
152 | } | |
619edcce KM |
153 | #endif |
154 | } else { | |
155 | /* | |
156 | * vm_object_lookup() gains a reference and also | |
157 | * removes the object from the cache. | |
158 | */ | |
159 | devp = (dev_pager_t)pager->pg_data; | |
160 | if (vm_object_lookup(pager) != devp->devp_object) | |
161 | panic("dev_pager_setup: bad object"); | |
162 | } | |
619edcce KM |
163 | return(pager); |
164 | ||
165 | } | |
166 | ||
167 | void | |
168 | dev_pager_dealloc(pager) | |
169 | vm_pager_t pager; | |
170 | { | |
171 | dev_pager_t devp = (dev_pager_t)pager->pg_data; | |
172 | register vm_object_t object; | |
173 | ||
174 | #ifdef DEBUG | |
175 | if (dpagerdebug & DDB_FOLLOW) | |
176 | printf("dev_pager_dealloc(%x)\n", pager); | |
177 | #endif | |
178 | queue_remove(&dev_pager_list, devp, dev_pager_t, devp_list); | |
179 | object = devp->devp_object; | |
180 | #ifdef DEBUG | |
181 | if (dpagerdebug & DDB_ALLOC) | |
182 | printf("dev_pager_dealloc: devp %x object %x pages %d@%x\n", | |
183 | devp, object, devp->devp_npages, devp->devp_pages); | |
184 | #endif | |
185 | while (!queue_empty(&object->memq)) | |
186 | vm_page_remove((vm_page_t)queue_first(&object->memq)); | |
a9966b2d | 187 | kmem_free(kernel_map, (vm_offset_t)devp->devp_pages, |
619edcce KM |
188 | devp->devp_npages * sizeof(struct vm_page)); |
189 | free((caddr_t)devp, M_VMPGDATA); | |
190 | pager->pg_data = 0; | |
191 | } | |
192 | ||
193 | dev_pager_getpage(pager, m, sync) | |
194 | vm_pager_t pager; | |
195 | vm_page_t m; | |
196 | boolean_t sync; | |
197 | { | |
198 | #ifdef DEBUG | |
199 | if (dpagerdebug & DDB_FOLLOW) | |
200 | printf("dev_pager_getpage(%x, %x)\n", pager, m); | |
201 | #endif | |
202 | return(VM_PAGER_BAD); | |
203 | } | |
204 | ||
205 | dev_pager_putpage(pager, m, sync) | |
206 | vm_pager_t pager; | |
207 | vm_page_t m; | |
208 | boolean_t sync; | |
209 | { | |
210 | #ifdef DEBUG | |
211 | if (dpagerdebug & DDB_FOLLOW) | |
212 | printf("dev_pager_putpage(%x, %x)\n", pager, m); | |
213 | #endif | |
ffe0d082 | 214 | if (pager == NULL) |
619edcce KM |
215 | return; |
216 | panic("dev_pager_putpage called"); | |
217 | } | |
218 | ||
219 | boolean_t | |
220 | dev_pager_haspage(pager, offset) | |
221 | vm_pager_t pager; | |
222 | vm_offset_t offset; | |
223 | { | |
224 | #ifdef DEBUG | |
225 | if (dpagerdebug & DDB_FOLLOW) | |
226 | printf("dev_pager_haspage(%x, %x)\n", pager, offset); | |
227 | #endif | |
228 | return(TRUE); | |
229 | } | |
230 | #endif |