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1.1 root 1: /*
2: * Copyright (c) 1991 Regents of the University of California.
3: * All rights reserved.
4: *
5: * This code is derived from software contributed to Berkeley by
6: * The Mach Operating System project at Carnegie-Mellon University.
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: * 1. Redistributions of source code must retain the above copyright
12: * notice, this list of conditions and the following disclaimer.
13: * 2. Redistributions in binary form must reproduce the above copyright
14: * notice, this list of conditions and the following disclaimer in the
15: * documentation and/or other materials provided with the distribution.
16: * 3. All advertising materials mentioning features or use of this software
17: * must display the following acknowledgement:
18: * This product includes software developed by the University of
19: * California, Berkeley and its contributors.
20: * 4. Neither the name of the University nor the names of its contributors
21: * may be used to endorse or promote products derived from this software
22: * without specific prior written permission.
23: *
24: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
25: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
26: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
27: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
28: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
29: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
30: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
31: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
32: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
33: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
34: * SUCH DAMAGE.
35: *
36: * @(#)vm_pager.c 7.4 (Berkeley) 5/7/91
37: *
38: *
39: * Copyright (c) 1987, 1990 Carnegie-Mellon University.
40: * All rights reserved.
41: *
42: * Authors: Avadis Tevanian, Jr., Michael Wayne Young
43: *
44: * Permission to use, copy, modify and distribute this software and
45: * its documentation is hereby granted, provided that both the copyright
46: * notice and this permission notice appear in all copies of the
47: * software, derivative works or modified versions, and any portions
48: * thereof, and that both notices appear in supporting documentation.
49: *
50: * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
51: * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
52: * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
53: *
54: * Carnegie Mellon requests users of this software to return to
55: *
56: * Software Distribution Coordinator or [email protected]
57: * School of Computer Science
58: * Carnegie Mellon University
59: * Pittsburgh PA 15213-3890
60: *
61: * any improvements or extensions that they make and grant Carnegie the
62: * rights to redistribute these changes.
1.1.1.2 ! root 63: *
! 64: * PATCHES MAGIC LEVEL PATCH THAT GOT US HERE
! 65: * -------------------- ----- ----------------------
! 66: * CURRENT PATCH LEVEL: 1 00063
! 67: * -------------------- ----- ----------------------
! 68: *
! 69: * 28 Nov 1991 Poul-Henning Kamp Speedup processing
1.1 root 70: */
71:
72: /*
73: * Paging space routine stubs. Emulates a matchmaker-like interface
74: * for builtin pagers.
75: */
76:
77: #include "param.h"
78: #include "malloc.h"
79:
80: #include "vm.h"
81: #include "vm_page.h"
82: #include "vm_kern.h"
83:
84: #include "swappager.h"
85:
86: #if NSWAPPAGER > 0
87: extern struct pagerops swappagerops;
88: #else
89: #define swappagerops NULL
90: #endif
91: #include "vnodepager.h"
92: #if NVNODEPAGER > 0
93: extern struct pagerops vnodepagerops;
94: #else
95: #define vnodepagerops NULL
96: #endif
97: #include "devpager.h"
98: #if NDEVPAGER > 0
99: extern struct pagerops devicepagerops;
100: #else
101: #define devicepagerops NULL
102: #endif
103:
104: struct pagerops *pagertab[] = {
105: &swappagerops, /* PG_SWAP */
106: &vnodepagerops, /* PG_VNODE */
107: &devicepagerops, /* PG_DEV */
108: };
109: int npagers = sizeof (pagertab) / sizeof (pagertab[0]);
110:
111: struct pagerops *dfltpagerops = NULL; /* default pager */
112:
113: /*
114: * Kernel address space for mapping pages.
115: * Used by pagers where KVAs are needed for IO.
116: */
117: #define PAGER_MAP_SIZE (256 * PAGE_SIZE)
118: vm_map_t pager_map;
119: vm_offset_t pager_sva, pager_eva;
120:
121: void
122: vm_pager_init()
123: {
124: struct pagerops **pgops;
125:
126: /*
127: * Allocate a kernel submap for tracking get/put page mappings
128: */
129: pager_map = kmem_suballoc(kernel_map, &pager_sva, &pager_eva,
130: PAGER_MAP_SIZE, FALSE);
131: /*
132: * Initialize known pagers
133: */
134: for (pgops = pagertab; pgops < &pagertab[npagers]; pgops++)
135: (*(*pgops)->pgo_init)();
136: if (dfltpagerops == NULL)
137: panic("no default pager");
138: }
139:
140: /*
141: * Allocate an instance of a pager of the given type.
142: */
143: vm_pager_t
144: vm_pager_allocate(type, handle, size, prot)
145: int type;
146: caddr_t handle;
147: vm_size_t size;
148: vm_prot_t prot;
149: {
150: vm_pager_t pager;
151: struct pagerops *ops;
152:
153: ops = (type == PG_DFLT) ? dfltpagerops : pagertab[type];
154: return((*ops->pgo_alloc)(handle, size, prot));
155: }
156:
157: void
158: vm_pager_deallocate(pager)
159: vm_pager_t pager;
160: {
161: if (pager == NULL)
162: panic("vm_pager_deallocate: null pager");
163:
164: VM_PAGER_DEALLOC(pager);
165: }
166:
167: vm_pager_get(pager, m, sync)
168: vm_pager_t pager;
169: vm_page_t m;
170: boolean_t sync;
171: {
172: extern boolean_t vm_page_zero_fill();
173:
174: if (pager == NULL)
175: return(vm_page_zero_fill(m) ? VM_PAGER_OK : VM_PAGER_FAIL);
176: return(VM_PAGER_GET(pager, m, sync));
177: }
178:
179: vm_pager_put(pager, m, sync)
180: vm_pager_t pager;
181: vm_page_t m;
182: boolean_t sync;
183: {
184: if (pager == NULL)
185: panic("vm_pager_put: null pager");
186: return(VM_PAGER_PUT(pager, m, sync));
187: }
188:
189: boolean_t
190: vm_pager_has_page(pager, offset)
191: vm_pager_t pager;
192: vm_offset_t offset;
193: {
194: if (pager == NULL)
195: panic("vm_pager_has_page");
196: return(VM_PAGER_HASPAGE(pager, offset));
197: }
198:
199: /*
200: * Called by pageout daemon before going back to sleep.
201: * Gives pagers a chance to clean up any completed async pageing operations.
202: */
203: void
204: vm_pager_sync()
205: {
206: struct pagerops **pgops;
207:
208: for (pgops = pagertab; pgops < &pagertab[npagers]; pgops++)
209: (*(*pgops)->pgo_putpage)(NULL, NULL, FALSE);
210: }
211:
212: vm_offset_t
213: vm_pager_map_page(m)
214: vm_page_t m;
215: {
216: vm_offset_t kva;
217:
218: #ifdef DEBUG
219: if (!m->busy || m->active)
220: panic("vm_pager_map_page: page active or not busy");
221: if (m->pagerowned)
222: printf("vm_pager_map_page: page %x already in pager\n", m);
223: #endif
224: kva = kmem_alloc_wait(pager_map, PAGE_SIZE);
225: #ifdef DEBUG
226: m->pagerowned = 1;
227: #endif
228: pmap_enter(vm_map_pmap(pager_map), kva, VM_PAGE_TO_PHYS(m),
229: VM_PROT_DEFAULT, TRUE);
230: return(kva);
231: }
232:
233: void
234: vm_pager_unmap_page(kva)
235: vm_offset_t kva;
236: {
237: #ifdef DEBUG
238: vm_page_t m;
239:
240: m = PHYS_TO_VM_PAGE(pmap_extract(vm_map_pmap(pager_map), kva));
241: #endif
242: kmem_free_wakeup(pager_map, kva, PAGE_SIZE);
243: #ifdef DEBUG
244: if (m->pagerowned)
245: m->pagerowned = 0;
246: else
247: printf("vm_pager_unmap_page: page %x(%x/%x) not owned\n",
248: m, kva, VM_PAGE_TO_PHYS(m));
249: #endif
250: }
251:
252: vm_pager_t
253: vm_pager_lookup(list, handle)
254: register queue_head_t *list;
255: caddr_t handle;
256: {
257: register vm_pager_t pager;
258:
259: pager = (vm_pager_t) queue_first(list);
260: while (!queue_end(list, (queue_entry_t)pager)) {
261: if (pager->pg_handle == handle)
262: return(pager);
263: pager = (vm_pager_t) queue_next(&pager->pg_list);
264: }
265: return(NULL);
266: }
267:
268: /*
269: * This routine gains a reference to the object.
270: * Explicit deallocation is necessary.
271: */
272: pager_cache(object, should_cache)
273: vm_object_t object;
274: boolean_t should_cache;
275: {
276: if (object == NULL)
277: return(KERN_INVALID_ARGUMENT);
278:
279: vm_object_cache_lock();
280: vm_object_lock(object);
281: object->can_persist = should_cache;
282: vm_object_unlock(object);
283: vm_object_cache_unlock();
284:
285: vm_object_deallocate(object);
286:
287: return(KERN_SUCCESS);
288: }
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