1 | /* $NetBSD: uvm_map.h,v 1.73 2016/05/25 17:43:58 christos 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@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) { \ |
85 | if ((VA) > (ENTRY)->start && (VA) < (ENTRY)->end) { \ |
86 | uvm_map_clip_start(MAP,ENTRY,VA); \ |
87 | } \ |
88 | } |
89 | |
90 | /* |
91 | * UVM_MAP_CLIP_END: ensure that the entry ends at or before |
92 | * the ending address, if it does't we split the entry. |
93 | * |
94 | * => map must be locked by caller |
95 | */ |
96 | |
97 | #define UVM_MAP_CLIP_END(MAP,ENTRY,VA) { \ |
98 | if ((VA) > (ENTRY)->start && (VA) < (ENTRY)->end) { \ |
99 | uvm_map_clip_end(MAP,ENTRY,VA); \ |
100 | } \ |
101 | } |
102 | |
103 | /* |
104 | * extract flags |
105 | */ |
106 | #define 0x01 /* remove mapping from old map */ |
107 | #define 0x02 /* try to keep it contig */ |
108 | #define 0x04 /* use quick refs */ |
109 | #define 0x08 /* set prot to maxprot as we go */ |
110 | #define 0x10 /* caller did uvm_map_reserve() */ |
111 | #define 0x20 /* set prot to UVM_PROT_ALL */ |
112 | |
113 | #endif /* _KERNEL */ |
114 | |
115 | #include <sys/rbtree.h> |
116 | #include <sys/pool.h> |
117 | #include <sys/rwlock.h> |
118 | #include <sys/mutex.h> |
119 | #include <sys/condvar.h> |
120 | |
121 | #include <uvm/uvm_anon.h> |
122 | |
123 | /* |
124 | * Address map entries consist of start and end addresses, |
125 | * a VM object (or sharing map) and offset into that object, |
126 | * and user-exported inheritance and protection information. |
127 | * Also included is control information for virtual copy operations. |
128 | */ |
129 | struct vm_map_entry { |
130 | struct rb_node rb_node; /* tree information */ |
131 | vsize_t gap; /* free space after */ |
132 | vsize_t maxgap; /* space in subtree */ |
133 | struct vm_map_entry *prev; /* previous entry */ |
134 | struct vm_map_entry *next; /* next entry */ |
135 | vaddr_t start; /* start address */ |
136 | vaddr_t end; /* end address */ |
137 | union { |
138 | struct uvm_object *uvm_obj; /* uvm object */ |
139 | struct vm_map *sub_map; /* belongs to another map */ |
140 | } object; /* object I point to */ |
141 | voff_t offset; /* offset into object */ |
142 | int etype; /* entry type */ |
143 | vm_prot_t protection; /* protection code */ |
144 | vm_prot_t max_protection; /* maximum protection */ |
145 | vm_inherit_t inheritance; /* inheritance */ |
146 | int wired_count; /* can be paged if == 0 */ |
147 | struct vm_aref aref; /* anonymous overlay */ |
148 | int advice; /* madvise advice */ |
149 | uint32_t map_attrib; /* uvm-external map attributes */ |
150 | #define uvm_map_entry_stop_copy flags |
151 | u_int8_t flags; /* flags */ |
152 | |
153 | #define UVM_MAP_KERNEL 0x01 /* kernel map entry */ |
154 | #define UVM_MAP_STATIC 0x04 /* special static entries */ |
155 | #define UVM_MAP_NOMERGE 0x08 /* this entry is not mergable */ |
156 | |
157 | }; |
158 | |
159 | #define VM_MAPENT_ISWIRED(entry) ((entry)->wired_count != 0) |
160 | |
161 | /* |
162 | * Maps are doubly-linked lists of map entries, kept sorted |
163 | * by address. A single hint is provided to start |
164 | * searches again from the last successful search, |
165 | * insertion, or removal. |
166 | * |
167 | * LOCKING PROTOCOL NOTES: |
168 | * ----------------------- |
169 | * |
170 | * VM map locking is a little complicated. There are both shared |
171 | * and exclusive locks on maps. However, it is sometimes required |
172 | * to downgrade an exclusive lock to a shared lock, and upgrade to |
173 | * an exclusive lock again (to perform error recovery). However, |
174 | * another thread *must not* queue itself to receive an exclusive |
175 | * lock while before we upgrade back to exclusive, otherwise the |
176 | * error recovery becomes extremely difficult, if not impossible. |
177 | * |
178 | * In order to prevent this scenario, we introduce the notion of |
179 | * a `busy' map. A `busy' map is read-locked, but other threads |
180 | * attempting to write-lock wait for this flag to clear before |
181 | * entering the lock manager. A map may only be marked busy |
182 | * when the map is write-locked (and then the map must be downgraded |
183 | * to read-locked), and may only be marked unbusy by the thread |
184 | * which marked it busy (holding *either* a read-lock or a |
185 | * write-lock, the latter being gained by an upgrade). |
186 | * |
187 | * Access to the map `flags' member is controlled by the `flags_lock' |
188 | * simple lock. Note that some flags are static (set once at map |
189 | * creation time, and never changed), and thus require no locking |
190 | * to check those flags. All flags which are r/w must be set or |
191 | * cleared while the `flags_lock' is asserted. Additional locking |
192 | * requirements are: |
193 | * |
194 | * VM_MAP_PAGEABLE r/o static flag; no locking required |
195 | * |
196 | * VM_MAP_WIREFUTURE r/w; may only be set or cleared when |
197 | * map is write-locked. may be tested |
198 | * without asserting `flags_lock'. |
199 | * |
200 | * VM_MAP_DYING r/o; set when a vmspace is being |
201 | * destroyed to indicate that updates |
202 | * to the pmap can be skipped. |
203 | * |
204 | * VM_MAP_TOPDOWN r/o; set when the vmspace is |
205 | * created if the unspecified map |
206 | * allocations are to be arranged in |
207 | * a "top down" manner. |
208 | */ |
209 | struct vm_map { |
210 | struct pmap * pmap; /* Physical map */ |
211 | krwlock_t lock; /* Non-intrsafe lock */ |
212 | struct lwp * busy; /* LWP holding map busy */ |
213 | kmutex_t misc_lock; /* Lock for ref_count, cv */ |
214 | kcondvar_t cv; /* For signalling */ |
215 | int flags; /* flags */ |
216 | struct rb_tree rb_tree; /* Tree for entries */ |
217 | struct vm_map_entry ; /* List of entries */ |
218 | int nentries; /* Number of entries */ |
219 | vsize_t size; /* virtual size */ |
220 | int ref_count; /* Reference count */ |
221 | struct vm_map_entry * hint; /* hint for quick lookups */ |
222 | struct vm_map_entry * first_free; /* First free space hint */ |
223 | unsigned int timestamp; /* Version number */ |
224 | }; |
225 | |
226 | #if defined(_KERNEL) |
227 | |
228 | #include <sys/callback.h> |
229 | |
230 | #endif /* defined(_KERNEL) */ |
231 | |
232 | #define VM_MAP_IS_KERNEL(map) (vm_map_pmap(map) == pmap_kernel()) |
233 | |
234 | /* vm_map flags */ |
235 | #define VM_MAP_PAGEABLE 0x01 /* ro: entries are pageable */ |
236 | #define VM_MAP_WIREFUTURE 0x04 /* rw: wire future mappings */ |
237 | #define VM_MAP_DYING 0x20 /* rw: map is being destroyed */ |
238 | #define VM_MAP_TOPDOWN 0x40 /* ro: arrange map top-down */ |
239 | #define VM_MAP_WANTVA 0x100 /* rw: want va */ |
240 | |
241 | #ifdef _KERNEL |
242 | struct uvm_map_args { |
243 | struct vm_map_entry *uma_prev; |
244 | |
245 | vaddr_t uma_start; |
246 | vsize_t uma_size; |
247 | |
248 | struct uvm_object *uma_uobj; |
249 | voff_t uma_uoffset; |
250 | |
251 | uvm_flag_t uma_flags; |
252 | }; |
253 | #endif /* _KERNEL */ |
254 | |
255 | /* |
256 | * globals: |
257 | */ |
258 | |
259 | #ifdef _KERNEL |
260 | |
261 | #include <sys/proc.h> |
262 | |
263 | #ifdef PMAP_GROWKERNEL |
264 | extern vaddr_t uvm_maxkaddr; |
265 | #endif |
266 | |
267 | /* |
268 | * protos: the following prototypes define the interface to vm_map |
269 | */ |
270 | |
271 | void uvm_map_deallocate(struct vm_map *); |
272 | |
273 | int uvm_map_willneed(struct vm_map *, vaddr_t, vaddr_t); |
274 | int uvm_map_clean(struct vm_map *, vaddr_t, vaddr_t, int); |
275 | void uvm_map_clip_start(struct vm_map *, struct vm_map_entry *, |
276 | vaddr_t); |
277 | void uvm_map_clip_end(struct vm_map *, struct vm_map_entry *, |
278 | vaddr_t); |
279 | int (struct vm_map *, vaddr_t, vsize_t, |
280 | struct vm_map *, vaddr_t *, int); |
281 | struct vm_map_entry * |
282 | uvm_map_findspace(struct vm_map *, vaddr_t, vsize_t, |
283 | vaddr_t *, struct uvm_object *, voff_t, vsize_t, int); |
284 | int uvm_map_inherit(struct vm_map *, vaddr_t, vaddr_t, |
285 | vm_inherit_t); |
286 | int uvm_map_advice(struct vm_map *, vaddr_t, vaddr_t, int); |
287 | void uvm_map_init(void); |
288 | void uvm_map_init_caches(void); |
289 | bool uvm_map_lookup_entry(struct vm_map *, vaddr_t, |
290 | struct vm_map_entry **); |
291 | void uvm_map_reference(struct vm_map *); |
292 | int uvm_map_reserve(struct vm_map *, vsize_t, vaddr_t, vsize_t, |
293 | vaddr_t *, uvm_flag_t); |
294 | void uvm_map_setup(struct vm_map *, vaddr_t, vaddr_t, int); |
295 | int uvm_map_submap(struct vm_map *, vaddr_t, vaddr_t, |
296 | struct vm_map *); |
297 | void uvm_unmap1(struct vm_map *, vaddr_t, vaddr_t, int); |
298 | #define uvm_unmap(map, s, e) uvm_unmap1((map), (s), (e), 0) |
299 | void uvm_unmap_detach(struct vm_map_entry *,int); |
300 | void uvm_unmap_remove(struct vm_map *, vaddr_t, vaddr_t, |
301 | struct vm_map_entry **, int); |
302 | |
303 | int uvm_map_prepare(struct vm_map *, vaddr_t, vsize_t, |
304 | struct uvm_object *, voff_t, vsize_t, uvm_flag_t, |
305 | struct uvm_map_args *); |
306 | int uvm_map_enter(struct vm_map *, const struct uvm_map_args *, |
307 | struct vm_map_entry *); |
308 | |
309 | int uvm_mapent_trymerge(struct vm_map *, |
310 | struct vm_map_entry *, int); |
311 | #define UVM_MERGE_COPYING 1 |
312 | |
313 | bool vm_map_starved_p(struct vm_map *); |
314 | |
315 | /* |
316 | * VM map locking operations. |
317 | */ |
318 | |
319 | bool vm_map_lock_try(struct vm_map *); |
320 | void vm_map_lock(struct vm_map *); |
321 | void vm_map_unlock(struct vm_map *); |
322 | void vm_map_unbusy(struct vm_map *); |
323 | void vm_map_lock_read(struct vm_map *); |
324 | void vm_map_unlock_read(struct vm_map *); |
325 | void vm_map_busy(struct vm_map *); |
326 | bool vm_map_locked_p(struct vm_map *); |
327 | |
328 | void uvm_map_lock_entry(struct vm_map_entry *); |
329 | void uvm_map_unlock_entry(struct vm_map_entry *); |
330 | |
331 | #endif /* _KERNEL */ |
332 | |
333 | /* |
334 | * Functions implemented as macros |
335 | */ |
336 | #define vm_map_min(map) ((map)->header.end) |
337 | #define vm_map_max(map) ((map)->header.start) |
338 | #define vm_map_setmin(map, v) ((map)->header.end = (v)) |
339 | #define vm_map_setmax(map, v) ((map)->header.start = (v)) |
340 | |
341 | #define vm_map_pmap(map) ((map)->pmap) |
342 | |
343 | #endif /* _UVM_UVM_MAP_H_ */ |
344 | |