uvm_map.h revision 1.66 1 /* $NetBSD: uvm_map.h,v 1.66 2011/02/02 15:25:27 chuck Exp $ */
2
3 /*
4 * Copyright (c) 1997 Charles D. Cranor and Washington University.
5 * Copyright (c) 1991, 1993, The Regents of the University of California.
6 *
7 * All rights reserved.
8 *
9 * This code is derived from software contributed to Berkeley by
10 * The Mach Operating System project at Carnegie-Mellon University.
11 *
12 * Redistribution and use in source and binary forms, with or without
13 * modification, are permitted provided that the following conditions
14 * are met:
15 * 1. Redistributions of source code must retain the above copyright
16 * notice, this list of conditions and the following disclaimer.
17 * 2. Redistributions in binary form must reproduce the above copyright
18 * notice, this list of conditions and the following disclaimer in the
19 * documentation and/or other materials provided with the distribution.
20 * 3. 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_map.h 8.3 (Berkeley) 3/15/94
37 * from: Id: uvm_map.h,v 1.1.2.3 1998/02/07 01:16:55 chs Exp
38 *
39 *
40 * Copyright (c) 1987, 1990 Carnegie-Mellon University.
41 * All rights reserved.
42 *
43 * Permission to use, copy, modify and distribute this software and
44 * its documentation is hereby granted, provided that both the copyright
45 * notice and this permission notice appear in all copies of the
46 * software, derivative works or modified versions, and any portions
47 * thereof, and that both notices appear in supporting documentation.
48 *
49 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
50 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
51 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
52 *
53 * Carnegie Mellon requests users of this software to return to
54 *
55 * Software Distribution Coordinator or Software.Distribution (at) CS.CMU.EDU
56 * School of Computer Science
57 * Carnegie Mellon University
58 * Pittsburgh PA 15213-3890
59 *
60 * any improvements or extensions that they make and grant Carnegie the
61 * rights to redistribute these changes.
62 */
63
64 #ifndef _UVM_UVM_MAP_H_
65 #define _UVM_UVM_MAP_H_
66
67 /*
68 * uvm_map.h
69 */
70
71 #ifdef _KERNEL
72
73 /*
74 * macros
75 */
76
77 /*
78 * UVM_MAP_CLIP_START: ensure that the entry begins at or after
79 * the starting address, if it doesn't we split the entry.
80 *
81 * => map must be locked by caller
82 */
83
84 #define UVM_MAP_CLIP_START(MAP,ENTRY,VA,UMR) { \
85 if ((VA) > (ENTRY)->start) uvm_map_clip_start(MAP,ENTRY,VA,UMR); }
86
87 /*
88 * UVM_MAP_CLIP_END: ensure that the entry ends at or before
89 * the ending address, if it does't we split the entry.
90 *
91 * => map must be locked by caller
92 */
93
94 #define UVM_MAP_CLIP_END(MAP,ENTRY,VA,UMR) { \
95 if ((VA) < (ENTRY)->end) uvm_map_clip_end(MAP,ENTRY,VA,UMR); }
96
97 /*
98 * extract flags
99 */
100 #define UVM_EXTRACT_REMOVE 0x01 /* remove mapping from old map */
101 #define UVM_EXTRACT_CONTIG 0x02 /* try to keep it contig */
102 #define UVM_EXTRACT_QREF 0x04 /* use quick refs */
103 #define UVM_EXTRACT_FIXPROT 0x08 /* set prot to maxprot as we go */
104 #define UVM_EXTRACT_RESERVED 0x10 /* caller did uvm_map_reserve() */
105
106 #endif /* _KERNEL */
107
108 #include <sys/rbtree.h>
109 #include <sys/pool.h>
110 #include <sys/rwlock.h>
111 #include <sys/mutex.h>
112 #include <sys/condvar.h>
113
114 #include <uvm/uvm_anon.h>
115
116 /*
117 * Address map entries consist of start and end addresses,
118 * a VM object (or sharing map) and offset into that object,
119 * and user-exported inheritance and protection information.
120 * Also included is control information for virtual copy operations.
121 */
122 struct vm_map_entry {
123 struct rb_node rb_node; /* tree information */
124 vsize_t gap; /* free space after */
125 vsize_t maxgap; /* space in subtree */
126 struct vm_map_entry *prev; /* previous entry */
127 struct vm_map_entry *next; /* next entry */
128 vaddr_t start; /* start address */
129 vaddr_t end; /* end address */
130 union {
131 struct uvm_object *uvm_obj; /* uvm object */
132 struct vm_map *sub_map; /* belongs to another map */
133 } object; /* object I point to */
134 voff_t offset; /* offset into object */
135 int etype; /* entry type */
136 vm_prot_t protection; /* protection code */
137 vm_prot_t max_protection; /* maximum protection */
138 vm_inherit_t inheritance; /* inheritance */
139 int wired_count; /* can be paged if == 0 */
140 struct vm_aref aref; /* anonymous overlay */
141 int advice; /* madvise advice */
142 #define uvm_map_entry_stop_copy flags
143 u_int8_t flags; /* flags */
144
145 #define UVM_MAP_KERNEL 0x01 /* kernel map entry */
146 #define UVM_MAP_KMAPENT 0x02 /* contains map entries */
147 #define UVM_MAP_FIRST 0x04 /* the first special entry */
148 #define UVM_MAP_QUANTUM 0x08 /* allocated with
149 * UVM_FLAG_QUANTUM */
150 #define UVM_MAP_NOMERGE 0x10 /* this entry is not mergable */
151
152 };
153
154 #define VM_MAPENT_ISWIRED(entry) ((entry)->wired_count != 0)
155
156 /*
157 * Maps are doubly-linked lists of map entries, kept sorted
158 * by address. A single hint is provided to start
159 * searches again from the last successful search,
160 * insertion, or removal.
161 *
162 * LOCKING PROTOCOL NOTES:
163 * -----------------------
164 *
165 * VM map locking is a little complicated. There are both shared
166 * and exclusive locks on maps. However, it is sometimes required
167 * to downgrade an exclusive lock to a shared lock, and upgrade to
168 * an exclusive lock again (to perform error recovery). However,
169 * another thread *must not* queue itself to receive an exclusive
170 * lock while before we upgrade back to exclusive, otherwise the
171 * error recovery becomes extremely difficult, if not impossible.
172 *
173 * In order to prevent this scenario, we introduce the notion of
174 * a `busy' map. A `busy' map is read-locked, but other threads
175 * attempting to write-lock wait for this flag to clear before
176 * entering the lock manager. A map may only be marked busy
177 * when the map is write-locked (and then the map must be downgraded
178 * to read-locked), and may only be marked unbusy by the thread
179 * which marked it busy (holding *either* a read-lock or a
180 * write-lock, the latter being gained by an upgrade).
181 *
182 * Access to the map `flags' member is controlled by the `flags_lock'
183 * simple lock. Note that some flags are static (set once at map
184 * creation time, and never changed), and thus require no locking
185 * to check those flags. All flags which are r/w must be set or
186 * cleared while the `flags_lock' is asserted. Additional locking
187 * requirements are:
188 *
189 * VM_MAP_PAGEABLE r/o static flag; no locking required
190 *
191 * VM_MAP_INTRSAFE r/o static flag; no locking required
192 *
193 * VM_MAP_WIREFUTURE r/w; may only be set or cleared when
194 * map is write-locked. may be tested
195 * without asserting `flags_lock'.
196 *
197 * VM_MAP_DYING r/o; set when a vmspace is being
198 * destroyed to indicate that updates
199 * to the pmap can be skipped.
200 *
201 * VM_MAP_TOPDOWN r/o; set when the vmspace is
202 * created if the unspecified map
203 * allocations are to be arranged in
204 * a "top down" manner.
205 */
206 struct vm_map {
207 struct pmap * pmap; /* Physical map */
208 krwlock_t lock; /* Non-intrsafe lock */
209 struct lwp * busy; /* LWP holding map busy */
210 kmutex_t mutex; /* INTRSAFE lock */
211 kmutex_t misc_lock; /* Lock for ref_count, cv */
212 kcondvar_t cv; /* For signalling */
213 int flags; /* flags */
214 struct rb_tree rb_tree; /* Tree for entries */
215 struct vm_map_entry header; /* List of entries */
216 int nentries; /* Number of entries */
217 vsize_t size; /* virtual size */
218 int ref_count; /* Reference count */
219 struct vm_map_entry * hint; /* hint for quick lookups */
220 struct vm_map_entry * first_free; /* First free space hint */
221 unsigned int timestamp; /* Version number */
222 };
223
224 #if defined(_KERNEL)
225
226 #include <sys/callback.h>
227
228 struct vm_map_kernel {
229 struct vm_map vmk_map;
230 LIST_HEAD(, uvm_kmapent_hdr) vmk_kentry_free;
231 /* Freelist of map entry */
232 struct vm_map_entry *vmk_merged_entries;
233 /* Merged entries, kept for later splitting */
234
235 struct callback_head vmk_reclaim_callback;
236 #if !defined(PMAP_MAP_POOLPAGE)
237 struct pool vmk_vacache; /* kva cache */
238 struct pool_allocator vmk_vacache_allocator; /* ... and its allocator */
239 #endif
240 };
241 #endif /* defined(_KERNEL) */
242
243 #define VM_MAP_IS_KERNEL(map) (vm_map_pmap(map) == pmap_kernel())
244
245 /* vm_map flags */
246 #define VM_MAP_PAGEABLE 0x01 /* ro: entries are pageable */
247 #define VM_MAP_INTRSAFE 0x02 /* ro: interrupt safe map */
248 #define VM_MAP_WIREFUTURE 0x04 /* rw: wire future mappings */
249 #define VM_MAP_DYING 0x20 /* rw: map is being destroyed */
250 #define VM_MAP_TOPDOWN 0x40 /* ro: arrange map top-down */
251 #define VM_MAP_VACACHE 0x80 /* ro: use kva cache */
252 #define VM_MAP_WANTVA 0x100 /* rw: want va */
253
254 #ifdef _KERNEL
255 struct uvm_mapent_reservation {
256 struct vm_map_entry *umr_entries[2];
257 int umr_nentries;
258 };
259 #define UMR_EMPTY(umr) ((umr) == NULL || (umr)->umr_nentries == 0)
260 #define UMR_GETENTRY(umr) ((umr)->umr_entries[--(umr)->umr_nentries])
261 #define UMR_PUTENTRY(umr, ent) \
262 (umr)->umr_entries[(umr)->umr_nentries++] = (ent)
263
264 struct uvm_map_args {
265 struct vm_map_entry *uma_prev;
266
267 vaddr_t uma_start;
268 vsize_t uma_size;
269
270 struct uvm_object *uma_uobj;
271 voff_t uma_uoffset;
272
273 uvm_flag_t uma_flags;
274 };
275 #endif /* _KERNEL */
276
277 /*
278 * globals:
279 */
280
281 #ifdef _KERNEL
282
283 #include <sys/proc.h>
284
285 #ifdef PMAP_GROWKERNEL
286 extern vaddr_t uvm_maxkaddr;
287 #endif
288
289 /*
290 * protos: the following prototypes define the interface to vm_map
291 */
292
293 void uvm_map_deallocate(struct vm_map *);
294
295 int uvm_map_willneed(struct vm_map *, vaddr_t, vaddr_t);
296 int uvm_map_clean(struct vm_map *, vaddr_t, vaddr_t, int);
297 void uvm_map_clip_start(struct vm_map *, struct vm_map_entry *,
298 vaddr_t, struct uvm_mapent_reservation *);
299 void uvm_map_clip_end(struct vm_map *, struct vm_map_entry *,
300 vaddr_t, struct uvm_mapent_reservation *);
301 struct vm_map *uvm_map_create(pmap_t, vaddr_t, vaddr_t, int);
302 int uvm_map_extract(struct vm_map *, vaddr_t, vsize_t,
303 struct vm_map *, vaddr_t *, int);
304 struct vm_map_entry *
305 uvm_map_findspace(struct vm_map *, vaddr_t, vsize_t,
306 vaddr_t *, struct uvm_object *, voff_t, vsize_t, int);
307 int uvm_map_inherit(struct vm_map *, vaddr_t, vaddr_t,
308 vm_inherit_t);
309 int uvm_map_advice(struct vm_map *, vaddr_t, vaddr_t, int);
310 void uvm_map_init(void);
311 bool uvm_map_lookup_entry(struct vm_map *, vaddr_t,
312 struct vm_map_entry **);
313 void uvm_map_reference(struct vm_map *);
314 int uvm_map_reserve(struct vm_map *, vsize_t, vaddr_t, vsize_t,
315 vaddr_t *, uvm_flag_t);
316 void uvm_map_setup(struct vm_map *, vaddr_t, vaddr_t, int);
317 void uvm_map_setup_kernel(struct vm_map_kernel *,
318 vaddr_t, vaddr_t, int);
319 struct vm_map_kernel *
320 vm_map_to_kernel(struct vm_map *);
321 int uvm_map_submap(struct vm_map *, vaddr_t, vaddr_t,
322 struct vm_map *);
323 void uvm_unmap1(struct vm_map *, vaddr_t, vaddr_t, int);
324 #define uvm_unmap(map, s, e) uvm_unmap1((map), (s), (e), 0)
325 void uvm_unmap_detach(struct vm_map_entry *,int);
326 void uvm_unmap_remove(struct vm_map *, vaddr_t, vaddr_t,
327 struct vm_map_entry **, struct uvm_mapent_reservation *,
328 int);
329
330 int uvm_map_prepare(struct vm_map *, vaddr_t, vsize_t,
331 struct uvm_object *, voff_t, vsize_t, uvm_flag_t,
332 struct uvm_map_args *);
333 int uvm_map_enter(struct vm_map *, const struct uvm_map_args *,
334 struct vm_map_entry *);
335
336 int uvm_mapent_reserve(struct vm_map *,
337 struct uvm_mapent_reservation *, int, int);
338 void uvm_mapent_unreserve(struct vm_map *,
339 struct uvm_mapent_reservation *);
340
341 vsize_t uvm_mapent_overhead(vsize_t, int);
342
343 int uvm_mapent_trymerge(struct vm_map *,
344 struct vm_map_entry *, int);
345 #define UVM_MERGE_COPYING 1
346
347 bool vm_map_starved_p(struct vm_map *);
348
349 /*
350 * VM map locking operations.
351 */
352
353 bool vm_map_lock_try(struct vm_map *);
354 void vm_map_lock(struct vm_map *);
355 void vm_map_unlock(struct vm_map *);
356 void vm_map_unbusy(struct vm_map *);
357 void vm_map_lock_read(struct vm_map *);
358 void vm_map_unlock_read(struct vm_map *);
359 void vm_map_busy(struct vm_map *);
360 bool vm_map_locked_p(struct vm_map *);
361
362 #endif /* _KERNEL */
363
364 /*
365 * Functions implemented as macros
366 */
367 #define vm_map_min(map) ((map)->header.end)
368 #define vm_map_max(map) ((map)->header.start)
369 #define vm_map_setmin(map, v) ((map)->header.end = (v))
370 #define vm_map_setmax(map, v) ((map)->header.start = (v))
371
372 #define vm_map_pmap(map) ((map)->pmap)
373
374 #endif /* _UVM_UVM_MAP_H_ */
375