1 /** $MirOS: src/sys/uvm/uvm_fault_i.h,v 1.2 2005/03/06 21:28:39 tg Exp $ */
2 /* $OpenBSD: uvm_fault_i.h,v 1.10 2002/03/14 01:27:18 millert Exp $ */
3 /* $NetBSD: uvm_fault_i.h,v 1.11 2000/06/26 14:21:17 mrg Exp $ */
4
5 /*
6 *
7 * Copyright (c) 1997 Charles D. Cranor and Washington University.
8 * All rights reserved.
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 Charles D. Cranor and
21 * Washington University.
22 * 4. The name of the author may not be used to endorse or promote products
23 * derived from this software without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
26 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
27 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
28 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
29 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
30 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
31 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
32 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
33 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
34 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
35 *
36 * from: Id: uvm_fault_i.h,v 1.1.6.1 1997/12/08 16:07:12 chuck Exp
37 */
38
39 #ifndef _UVM_UVM_FAULT_I_H_
40 #define _UVM_UVM_FAULT_I_H_
41
42 /*
43 * uvm_fault_i.h: fault inline functions
44 */
45 static boolean_t uvmfault_check_intrsafe(struct uvm_faultinfo *);
46 static boolean_t uvmfault_lookup(struct uvm_faultinfo *, boolean_t);
47 static boolean_t uvmfault_relock(struct uvm_faultinfo *);
48 static void uvmfault_unlockall(struct uvm_faultinfo *, struct vm_amap *,
49 struct uvm_object *, struct vm_anon *);
50 static void uvmfault_unlockmaps(struct uvm_faultinfo *, boolean_t);
51
52 /*
53 * uvmfault_unlockmaps: unlock the maps
54 */
55
56 static __inline void
uvmfault_unlockmaps(ufi,write_locked)57 uvmfault_unlockmaps(ufi, write_locked)
58 struct uvm_faultinfo *ufi;
59 boolean_t write_locked;
60 {
61 /*
62 * ufi can be NULL when this isn't really a fault,
63 * but merely paging in anon data.
64 */
65
66 if (ufi == NULL) {
67 return;
68 }
69
70 if (write_locked) {
71 vm_map_unlock(ufi->map);
72 } else {
73 vm_map_unlock_read(ufi->map);
74 }
75 }
76
77 /*
78 * uvmfault_unlockall: unlock everything passed in.
79 *
80 * => maps must be read-locked (not write-locked).
81 */
82
83 static __inline void
uvmfault_unlockall(ufi,amap,uobj,anon)84 uvmfault_unlockall(ufi, amap, uobj, anon)
85 struct uvm_faultinfo *ufi;
86 struct vm_amap *amap;
87 struct uvm_object *uobj;
88 struct vm_anon *anon;
89 {
90
91 if (anon) {
92 simple_unlock(&anon->an_lock);
93 }
94 if (uobj) {
95 simple_unlock(&uobj->vmobjlock);
96 }
97 if (amap) {
98 amap_unlock(amap);
99 }
100 uvmfault_unlockmaps(ufi, FALSE);
101 }
102
103 /*
104 * uvmfault_check_intrsafe: check for a virtual address managed by
105 * an interrupt-safe map.
106 *
107 * => caller must provide a uvm_faultinfo structure with the IN
108 * params properly filled in
109 * => if we find an intersafe VA, we fill in ufi->map, and return TRUE
110 */
111
112 static __inline boolean_t
uvmfault_check_intrsafe(ufi)113 uvmfault_check_intrsafe(ufi)
114 struct uvm_faultinfo *ufi;
115 {
116 struct vm_map_intrsafe *vmi;
117 int s;
118
119 s = vmi_list_lock();
120 for (vmi = LIST_FIRST(&vmi_list); vmi != NULL;
121 vmi = LIST_NEXT(vmi, vmi_list)) {
122 if (ufi->orig_rvaddr >= vm_map_min(&vmi->vmi_map) &&
123 ufi->orig_rvaddr < vm_map_max(&vmi->vmi_map))
124 break;
125 }
126 vmi_list_unlock(s);
127
128 if (vmi != NULL) {
129 ufi->map = &vmi->vmi_map;
130 return (TRUE);
131 }
132
133 return (FALSE);
134 }
135
136 /*
137 * uvmfault_lookup: lookup a virtual address in a map
138 *
139 * => caller must provide a uvm_faultinfo structure with the IN
140 * params properly filled in
141 * => we will lookup the map entry (handling submaps) as we go
142 * => if the lookup is a success we will return with the maps locked
143 * => if "write_lock" is TRUE, we write_lock the map, otherwise we only
144 * get a read lock.
145 * => note that submaps can only appear in the kernel and they are
146 * required to use the same virtual addresses as the map they
147 * are referenced by (thus address translation between the main
148 * map and the submap is unnecessary).
149 */
150
151 static __inline boolean_t
uvmfault_lookup(ufi,write_lock)152 uvmfault_lookup(ufi, write_lock)
153 struct uvm_faultinfo *ufi;
154 boolean_t write_lock;
155 {
156 vm_map_t tmpmap;
157
158 /*
159 * init ufi values for lookup.
160 */
161
162 ufi->map = ufi->orig_map;
163 ufi->size = ufi->orig_size;
164
165 /*
166 * keep going down levels until we are done. note that there can
167 * only be two levels so we won't loop very long.
168 */
169
170 while (1) {
171
172 /*
173 * lock map
174 */
175 if (write_lock) {
176 vm_map_lock(ufi->map);
177 } else {
178 vm_map_lock_read(ufi->map);
179 }
180
181 /*
182 * lookup
183 */
184 if (!uvm_map_lookup_entry(ufi->map, ufi->orig_rvaddr,
185 &ufi->entry)) {
186 uvmfault_unlockmaps(ufi, write_lock);
187 return(FALSE);
188 }
189
190 /*
191 * reduce size if necessary
192 */
193 if (ufi->entry->end - ufi->orig_rvaddr < ufi->size)
194 ufi->size = ufi->entry->end - ufi->orig_rvaddr;
195
196 /*
197 * submap? replace map with the submap and lookup again.
198 * note: VAs in submaps must match VAs in main map.
199 */
200 if (UVM_ET_ISSUBMAP(ufi->entry)) {
201 tmpmap = ufi->entry->object.sub_map;
202 if (write_lock) {
203 vm_map_unlock(ufi->map);
204 } else {
205 vm_map_unlock_read(ufi->map);
206 }
207 ufi->map = tmpmap;
208 continue;
209 }
210
211 /*
212 * got it!
213 */
214
215 ufi->mapv = ufi->map->timestamp;
216 return(TRUE);
217
218 } /* while loop */
219
220 /*NOTREACHED*/
221 }
222
223 /*
224 * uvmfault_relock: attempt to relock the same version of the map
225 *
226 * => fault data structures should be unlocked before calling.
227 * => if a success (TRUE) maps will be locked after call.
228 */
229
230 static __inline boolean_t
uvmfault_relock(ufi)231 uvmfault_relock(ufi)
232 struct uvm_faultinfo *ufi;
233 {
234 /*
235 * ufi can be NULL when this isn't really a fault,
236 * but merely paging in anon data.
237 */
238
239 if (ufi == NULL) {
240 return TRUE;
241 }
242
243 uvmexp.fltrelck++;
244
245 /*
246 * relock map. fail if version mismatch (in which case nothing
247 * gets locked).
248 */
249
250 vm_map_lock_read(ufi->map);
251 if (ufi->mapv != ufi->map->timestamp) {
252 vm_map_unlock_read(ufi->map);
253 return(FALSE);
254 }
255
256 uvmexp.fltrelckok++;
257 return(TRUE); /* got it! */
258 }
259
260 #endif /* _UVM_UVM_FAULT_I_H_ */
261