Commit | Line | Data |
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15637ed4 RG |
1 | /* |
2 | * Copyright (c) 1990 University of Utah. | |
0a8fbd8d DG |
3 | * Copyright (c) 1991, 1993 |
4 | * The Regents of the University of California. All rights reserved. | |
15637ed4 RG |
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 | * Redistribution and use in source and binary forms, with or without | |
11 | * modification, are permitted provided that the following conditions | |
12 | * are met: | |
13 | * 1. Redistributions of source code must retain the above copyright | |
14 | * notice, this list of conditions and the following disclaimer. | |
15 | * 2. Redistributions in binary form must reproduce the above copyright | |
16 | * notice, this list of conditions and the following disclaimer in the | |
17 | * documentation and/or other materials provided with the distribution. | |
18 | * 3. All advertising materials mentioning features or use of this software | |
19 | * must display the following acknowledgement: | |
20 | * This product includes software developed by the University of | |
21 | * California, Berkeley and its contributors. | |
22 | * 4. Neither the name of the University nor the names of its contributors | |
23 | * may be used to endorse or promote products derived from this software | |
24 | * without specific prior written permission. | |
25 | * | |
26 | * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND | |
27 | * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE | |
28 | * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE | |
29 | * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE | |
30 | * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL | |
31 | * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS | |
32 | * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) | |
33 | * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT | |
34 | * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY | |
35 | * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF | |
36 | * SUCH DAMAGE. | |
37 | * | |
0a8fbd8d | 38 | * @(#)device_pager.c 8.1 (Berkeley) 6/11/93 |
15637ed4 RG |
39 | */ |
40 | ||
41 | /* | |
42 | * Page to/from special files. | |
43 | */ | |
44 | ||
0a8fbd8d DG |
45 | #include <sys/param.h> |
46 | #include <sys/systm.h> | |
47 | #include <sys/conf.h> | |
48 | #include <sys/mman.h> | |
49 | #include <sys/malloc.h> | |
15637ed4 | 50 | |
0a8fbd8d DG |
51 | #include <vm/vm.h> |
52 | #include <vm/vm_kern.h> | |
53 | #include <vm/vm_page.h> | |
54 | #include <vm/device_pager.h> | |
15637ed4 | 55 | |
3ed7acd6 PR |
56 | #include "vnode.h" |
57 | #include "specdev.h" | |
15637ed4 | 58 | |
0a8fbd8d DG |
59 | queue_head_t dev_pager_list; /* list of managed devices */ |
60 | queue_head_t dev_pager_fakelist; /* list of available vm_page_t's */ | |
15637ed4 RG |
61 | |
62 | #ifdef DEBUG | |
63 | int dpagerdebug = 0; | |
64 | #define DDB_FOLLOW 0x01 | |
65 | #define DDB_INIT 0x02 | |
66 | #define DDB_ALLOC 0x04 | |
67 | #define DDB_FAIL 0x08 | |
68 | #endif | |
69 | ||
0a8fbd8d DG |
70 | static vm_pager_t dev_pager_alloc |
71 | __P((caddr_t, vm_size_t, vm_prot_t, vm_offset_t)); | |
72 | static void dev_pager_dealloc __P((vm_pager_t)); | |
73 | static int dev_pager_getpage | |
74 | __P((vm_pager_t, vm_page_t, boolean_t)); | |
75 | static boolean_t dev_pager_haspage __P((vm_pager_t, vm_offset_t)); | |
76 | static void dev_pager_init __P((void)); | |
77 | static int dev_pager_putpage | |
78 | __P((vm_pager_t, vm_page_t, boolean_t)); | |
79 | static vm_page_t dev_pager_getfake __P((vm_offset_t)); | |
80 | static void dev_pager_putfake __P((vm_page_t)); | |
81 | ||
82 | struct pagerops devicepagerops = { | |
83 | dev_pager_init, | |
84 | dev_pager_alloc, | |
85 | dev_pager_dealloc, | |
86 | dev_pager_getpage, | |
55768178 | 87 | 0, |
0a8fbd8d | 88 | dev_pager_putpage, |
22c84afa | 89 | 0, |
0a8fbd8d DG |
90 | dev_pager_haspage |
91 | }; | |
92 | ||
93 | static void | |
15637ed4 RG |
94 | dev_pager_init() |
95 | { | |
96 | #ifdef DEBUG | |
97 | if (dpagerdebug & DDB_FOLLOW) | |
98 | printf("dev_pager_init()\n"); | |
99 | #endif | |
100 | queue_init(&dev_pager_list); | |
0a8fbd8d | 101 | queue_init(&dev_pager_fakelist); |
15637ed4 RG |
102 | } |
103 | ||
0a8fbd8d DG |
104 | static vm_pager_t |
105 | dev_pager_alloc(handle, size, prot, foff) | |
15637ed4 RG |
106 | caddr_t handle; |
107 | vm_size_t size; | |
108 | vm_prot_t prot; | |
0a8fbd8d | 109 | vm_offset_t foff; |
15637ed4 | 110 | { |
2dbd2022 | 111 | dev_t dev; |
15637ed4 | 112 | vm_pager_t pager; |
0a8fbd8d DG |
113 | int (*mapfunc)(); |
114 | vm_object_t object; | |
115 | dev_pager_t devp; | |
116 | unsigned int npages, off; | |
15637ed4 RG |
117 | |
118 | #ifdef DEBUG | |
119 | if (dpagerdebug & DDB_FOLLOW) | |
0a8fbd8d DG |
120 | printf("dev_pager_alloc(%x, %x, %x, %x)\n", |
121 | handle, size, prot, foff); | |
15637ed4 | 122 | #endif |
0a8fbd8d | 123 | #ifdef DIAGNOSTIC |
15637ed4 RG |
124 | /* |
125 | * Pageout to device, should never happen. | |
126 | */ | |
127 | if (handle == NULL) | |
128 | panic("dev_pager_alloc called"); | |
0a8fbd8d DG |
129 | #endif |
130 | ||
131 | /* | |
132 | * Make sure this device can be mapped. | |
133 | */ | |
2dbd2022 DG |
134 | dev = (dev_t)(u_long)handle; |
135 | mapfunc = cdevsw[major(dev)].d_mmap; | |
0a8fbd8d DG |
136 | if (mapfunc == NULL || mapfunc == enodev || mapfunc == nullop) |
137 | return(NULL); | |
138 | ||
139 | /* | |
140 | * Offset should be page aligned. | |
141 | */ | |
55768178 | 142 | if (foff & (PAGE_SIZE-1)) |
0a8fbd8d | 143 | return(NULL); |
15637ed4 RG |
144 | |
145 | /* | |
0a8fbd8d DG |
146 | * Check that the specified range of the device allows the |
147 | * desired protection. | |
148 | * | |
149 | * XXX assumes VM_PROT_* == PROT_* | |
15637ed4 | 150 | */ |
0a8fbd8d DG |
151 | npages = atop(round_page(size)); |
152 | for (off = foff; npages--; off += PAGE_SIZE) | |
153 | if ((*mapfunc)(dev, off, (int)prot) == -1) | |
154 | return(NULL); | |
155 | ||
156 | /* | |
157 | * Look up pager, creating as necessary. | |
158 | */ | |
159 | top: | |
15637ed4 RG |
160 | pager = vm_pager_lookup(&dev_pager_list, handle); |
161 | if (pager == NULL) { | |
15637ed4 RG |
162 | /* |
163 | * Allocate and initialize pager structs | |
164 | */ | |
165 | pager = (vm_pager_t)malloc(sizeof *pager, M_VMPAGER, M_WAITOK); | |
166 | if (pager == NULL) | |
167 | return(NULL); | |
168 | devp = (dev_pager_t)malloc(sizeof *devp, M_VMPGDATA, M_WAITOK); | |
169 | if (devp == NULL) { | |
170 | free((caddr_t)pager, M_VMPAGER); | |
171 | return(NULL); | |
172 | } | |
15637ed4 RG |
173 | pager->pg_handle = handle; |
174 | pager->pg_ops = &devicepagerops; | |
175 | pager->pg_type = PG_DEVICE; | |
176 | pager->pg_data = (caddr_t)devp; | |
0a8fbd8d | 177 | queue_init(&devp->devp_pglist); |
15637ed4 | 178 | /* |
0a8fbd8d | 179 | * Allocate object and associate it with the pager. |
15637ed4 | 180 | */ |
0a8fbd8d | 181 | object = devp->devp_object = vm_object_allocate(0); |
15637ed4 | 182 | vm_object_enter(object, pager); |
0a8fbd8d | 183 | vm_object_setpager(object, pager, (vm_offset_t)foff, FALSE); |
15637ed4 RG |
184 | /* |
185 | * Finally, put it on the managed list so other can find it. | |
0a8fbd8d DG |
186 | * First we re-lookup in case someone else beat us to this |
187 | * point (due to blocking in the various mallocs). If so, | |
188 | * we free everything and start over. | |
15637ed4 | 189 | */ |
0a8fbd8d DG |
190 | if (vm_pager_lookup(&dev_pager_list, handle)) { |
191 | free((caddr_t)devp, M_VMPGDATA); | |
192 | free((caddr_t)pager, M_VMPAGER); | |
193 | goto top; | |
194 | } | |
15637ed4 RG |
195 | queue_enter(&dev_pager_list, pager, vm_pager_t, pg_list); |
196 | #ifdef DEBUG | |
0a8fbd8d DG |
197 | if (dpagerdebug & DDB_ALLOC) { |
198 | printf("dev_pager_alloc: pager %x devp %x object %x\n", | |
199 | pager, devp, object); | |
200 | vm_object_print(object, FALSE); | |
201 | } | |
15637ed4 RG |
202 | #endif |
203 | } else { | |
204 | /* | |
205 | * vm_object_lookup() gains a reference and also | |
206 | * removes the object from the cache. | |
207 | */ | |
0a8fbd8d DG |
208 | object = vm_object_lookup(pager); |
209 | #ifdef DIAGNOSTIC | |
15637ed4 | 210 | devp = (dev_pager_t)pager->pg_data; |
0a8fbd8d | 211 | if (object != devp->devp_object) |
15637ed4 | 212 | panic("dev_pager_setup: bad object"); |
15637ed4 | 213 | #endif |
0a8fbd8d | 214 | } |
15637ed4 | 215 | return(pager); |
15637ed4 RG |
216 | } |
217 | ||
0a8fbd8d | 218 | static void |
15637ed4 RG |
219 | dev_pager_dealloc(pager) |
220 | vm_pager_t pager; | |
221 | { | |
0a8fbd8d DG |
222 | dev_pager_t devp; |
223 | vm_object_t object; | |
224 | vm_page_t m; | |
15637ed4 RG |
225 | |
226 | #ifdef DEBUG | |
227 | if (dpagerdebug & DDB_FOLLOW) | |
228 | printf("dev_pager_dealloc(%x)\n", pager); | |
229 | #endif | |
230 | queue_remove(&dev_pager_list, pager, vm_pager_t, pg_list); | |
0a8fbd8d DG |
231 | /* |
232 | * Get the object. | |
233 | * Note: cannot use vm_object_lookup since object has already | |
234 | * been removed from the hash chain. | |
235 | */ | |
236 | devp = (dev_pager_t)pager->pg_data; | |
15637ed4 RG |
237 | object = devp->devp_object; |
238 | #ifdef DEBUG | |
239 | if (dpagerdebug & DDB_ALLOC) | |
0a8fbd8d | 240 | printf("dev_pager_dealloc: devp %x object %x\n", devp, object); |
15637ed4 | 241 | #endif |
0a8fbd8d DG |
242 | /* |
243 | * Free up our fake pages. | |
244 | */ | |
245 | while (!queue_empty(&devp->devp_pglist)) { | |
246 | queue_remove_first(&devp->devp_pglist, m, vm_page_t, pageq); | |
247 | dev_pager_putfake(m); | |
248 | } | |
15637ed4 RG |
249 | free((caddr_t)devp, M_VMPGDATA); |
250 | free((caddr_t)pager, M_VMPAGER); | |
15637ed4 RG |
251 | } |
252 | ||
0a8fbd8d | 253 | static int |
15637ed4 RG |
254 | dev_pager_getpage(pager, m, sync) |
255 | vm_pager_t pager; | |
256 | vm_page_t m; | |
257 | boolean_t sync; | |
258 | { | |
0a8fbd8d DG |
259 | register vm_object_t object; |
260 | vm_offset_t offset, paddr; | |
261 | vm_page_t page; | |
2dbd2022 | 262 | dev_t dev; |
55768178 | 263 | int s; |
0a8fbd8d DG |
264 | int (*mapfunc)(), prot; |
265 | ||
15637ed4 RG |
266 | #ifdef DEBUG |
267 | if (dpagerdebug & DDB_FOLLOW) | |
268 | printf("dev_pager_getpage(%x, %x)\n", pager, m); | |
269 | #endif | |
0a8fbd8d DG |
270 | |
271 | object = m->object; | |
2dbd2022 | 272 | dev = (dev_t)(u_long)pager->pg_handle; |
0a8fbd8d DG |
273 | offset = m->offset + object->paging_offset; |
274 | prot = PROT_READ; /* XXX should pass in? */ | |
2dbd2022 | 275 | mapfunc = cdevsw[major(dev)].d_mmap; |
9f6fb340 | 276 | |
0a8fbd8d DG |
277 | if (mapfunc == NULL || mapfunc == enodev || mapfunc == nullop) |
278 | panic("dev_pager_getpage: no map function"); | |
9f6fb340 DG |
279 | |
280 | paddr = pmap_phys_address((*mapfunc)((dev_t)dev, (int)offset, prot)); | |
0a8fbd8d DG |
281 | #ifdef DIAGNOSTIC |
282 | if (paddr == -1) | |
283 | panic("dev_pager_getpage: map function returns error"); | |
284 | #endif | |
285 | /* | |
286 | * Replace the passed in page with our own fake page and free | |
287 | * up the original. | |
288 | */ | |
289 | page = dev_pager_getfake(paddr); | |
290 | queue_enter(&((dev_pager_t)pager->pg_data)->devp_pglist, | |
291 | page, vm_page_t, pageq); | |
292 | vm_object_lock(object); | |
293 | vm_page_lock_queues(); | |
294 | vm_page_free(m); | |
295 | vm_page_unlock_queues(); | |
55768178 | 296 | s = splhigh(); |
0a8fbd8d | 297 | vm_page_insert(page, object, offset); |
55768178 | 298 | splx(s); |
0a8fbd8d DG |
299 | PAGE_WAKEUP(m); |
300 | if (offset + PAGE_SIZE > object->size) | |
301 | object->size = offset + PAGE_SIZE; /* XXX anal */ | |
302 | vm_object_unlock(object); | |
303 | ||
304 | return(VM_PAGER_OK); | |
15637ed4 RG |
305 | } |
306 | ||
0a8fbd8d | 307 | static int |
15637ed4 RG |
308 | dev_pager_putpage(pager, m, sync) |
309 | vm_pager_t pager; | |
310 | vm_page_t m; | |
311 | boolean_t sync; | |
312 | { | |
313 | #ifdef DEBUG | |
314 | if (dpagerdebug & DDB_FOLLOW) | |
315 | printf("dev_pager_putpage(%x, %x)\n", pager, m); | |
316 | #endif | |
317 | if (pager == NULL) | |
4c45483e | 318 | return 0; |
15637ed4 RG |
319 | panic("dev_pager_putpage called"); |
320 | } | |
321 | ||
0a8fbd8d | 322 | static boolean_t |
15637ed4 RG |
323 | dev_pager_haspage(pager, offset) |
324 | vm_pager_t pager; | |
325 | vm_offset_t offset; | |
326 | { | |
327 | #ifdef DEBUG | |
328 | if (dpagerdebug & DDB_FOLLOW) | |
329 | printf("dev_pager_haspage(%x, %x)\n", pager, offset); | |
330 | #endif | |
331 | return(TRUE); | |
332 | } | |
0a8fbd8d DG |
333 | |
334 | static vm_page_t | |
335 | dev_pager_getfake(paddr) | |
336 | vm_offset_t paddr; | |
337 | { | |
338 | vm_page_t m; | |
339 | int i; | |
340 | ||
341 | if (queue_empty(&dev_pager_fakelist)) { | |
342 | m = (vm_page_t)malloc(PAGE_SIZE, M_VMPGDATA, M_WAITOK); | |
343 | for (i = PAGE_SIZE / sizeof(*m); i > 0; i--) { | |
344 | queue_enter(&dev_pager_fakelist, m, vm_page_t, pageq); | |
345 | m++; | |
346 | } | |
347 | } | |
348 | queue_remove_first(&dev_pager_fakelist, m, vm_page_t, pageq); | |
9f6fb340 | 349 | |
0a8fbd8d | 350 | m->flags = PG_BUSY | PG_CLEAN | PG_FAKE | PG_FICTITIOUS; |
9f6fb340 | 351 | |
0a8fbd8d | 352 | m->wire_count = 1; |
9f6fb340 DG |
353 | m->phys_addr = paddr; |
354 | ||
0a8fbd8d DG |
355 | return(m); |
356 | } | |
357 | ||
358 | static void | |
359 | dev_pager_putfake(m) | |
360 | vm_page_t m; | |
361 | { | |
362 | #ifdef DIAGNOSTIC | |
0a8fbd8d | 363 | if (!(m->flags & PG_FICTITIOUS)) |
0a8fbd8d DG |
364 | panic("dev_pager_putfake: bad page"); |
365 | #endif | |
366 | queue_enter(&dev_pager_fakelist, m, vm_page_t, pageq); | |
367 | } |