Annotation of sys/uvm/uvm_amap_i.h, Revision 1.1.1.1
1.1 nbrk 1: /* $OpenBSD: uvm_amap_i.h,v 1.18 2007/06/18 21:51:15 pedro Exp $ */
2: /* $NetBSD: uvm_amap_i.h,v 1.15 2000/11/25 06:27:59 chs Exp $ */
3:
4: /*
5: *
6: * Copyright (c) 1997 Charles D. Cranor and Washington University.
7: * All rights reserved.
8: *
9: * Redistribution and use in source and binary forms, with or without
10: * modification, are permitted provided that the following conditions
11: * are met:
12: * 1. Redistributions of source code must retain the above copyright
13: * notice, this list of conditions and the following disclaimer.
14: * 2. Redistributions in binary form must reproduce the above copyright
15: * notice, this list of conditions and the following disclaimer in the
16: * documentation and/or other materials provided with the distribution.
17: * 3. All advertising materials mentioning features or use of this software
18: * must display the following acknowledgement:
19: * This product includes software developed by Charles D. Cranor and
20: * Washington University.
21: * 4. The name of the author may not be used to endorse or promote products
22: * derived from this software without specific prior written permission.
23: *
24: * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
25: * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
26: * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
27: * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
28: * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
29: * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
30: * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
31: * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
32: * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
33: * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34: *
35: * from: Id: uvm_amap_i.h,v 1.1.2.4 1998/01/05 18:12:57 chuck Exp
36: */
37:
38: #ifndef _UVM_UVM_AMAP_I_H_
39: #define _UVM_UVM_AMAP_I_H_
40:
41: /*
42: * uvm_amap_i.h
43: */
44:
45: /*
46: * if inlines are enabled always pull in these functions, otherwise
47: * pull them in only once (when we are compiling uvm_amap.c).
48: */
49:
50: #if defined(UVM_AMAP_INLINE) || defined(UVM_AMAP_C)
51:
52: /*
53: * amap_lookup: look up a page in an amap
54: *
55: * => amap should be locked by caller.
56: */
57: AMAP_INLINE struct vm_anon *
58: amap_lookup(aref, offset)
59: struct vm_aref *aref;
60: vaddr_t offset;
61: {
62: int slot;
63: struct vm_amap *amap = aref->ar_amap;
64: UVMHIST_FUNC("amap_lookup"); UVMHIST_CALLED(maphist);
65:
66: AMAP_B2SLOT(slot, offset);
67: slot += aref->ar_pageoff;
68:
69: if (slot >= amap->am_nslot)
70: panic("amap_lookup: offset out of range");
71:
72: UVMHIST_LOG(maphist, "<- done (amap=%p, offset=0x%lx, result=%p)",
73: amap, offset, amap->am_anon[slot], 0);
74: return(amap->am_anon[slot]);
75: }
76:
77: /*
78: * amap_lookups: look up a range of pages in an amap
79: *
80: * => amap should be locked by caller.
81: * => XXXCDC: this interface is biased toward array-based amaps. fix.
82: */
83: AMAP_INLINE void
84: amap_lookups(aref, offset, anons, npages)
85: struct vm_aref *aref;
86: vaddr_t offset;
87: struct vm_anon **anons;
88: int npages;
89: {
90: int slot;
91: struct vm_amap *amap = aref->ar_amap;
92: UVMHIST_FUNC("amap_lookups"); UVMHIST_CALLED(maphist);
93:
94: AMAP_B2SLOT(slot, offset);
95: slot += aref->ar_pageoff;
96:
97: UVMHIST_LOG(maphist, " slot=%ld, npages=%ld, nslot=%ld", slot, npages,
98: amap->am_nslot, 0);
99:
100: if ((slot + (npages - 1)) >= amap->am_nslot)
101: panic("amap_lookups: offset out of range");
102:
103: memcpy(anons, &amap->am_anon[slot], npages * sizeof(struct vm_anon *));
104:
105: UVMHIST_LOG(maphist, "<- done", 0, 0, 0, 0);
106: return;
107: }
108:
109: /*
110: * amap_add: add (or replace) a page to an amap
111: *
112: * => caller must lock amap.
113: * => if (replace) caller must lock anon because we might have to call
114: * pmap_page_protect on the anon's page.
115: * => returns an "offset" which is meaningful to amap_unadd().
116: */
117: AMAP_INLINE void
118: amap_add(aref, offset, anon, replace)
119: struct vm_aref *aref;
120: vaddr_t offset;
121: struct vm_anon *anon;
122: boolean_t replace;
123: {
124: int slot;
125: struct vm_amap *amap = aref->ar_amap;
126: UVMHIST_FUNC("amap_add"); UVMHIST_CALLED(maphist);
127:
128: AMAP_B2SLOT(slot, offset);
129: slot += aref->ar_pageoff;
130:
131: if (slot >= amap->am_nslot)
132: panic("amap_add: offset out of range");
133:
134: if (replace) {
135:
136: if (amap->am_anon[slot] == NULL)
137: panic("amap_add: replacing null anon");
138: if (amap->am_anon[slot]->an_page != NULL &&
139: (amap->am_flags & AMAP_SHARED) != 0) {
140: pmap_page_protect(amap->am_anon[slot]->an_page,
141: VM_PROT_NONE);
142: /*
143: * XXX: suppose page is supposed to be wired somewhere?
144: */
145: }
146: } else { /* !replace */
147: if (amap->am_anon[slot] != NULL)
148: panic("amap_add: slot in use");
149:
150: amap->am_bckptr[slot] = amap->am_nused;
151: amap->am_slots[amap->am_nused] = slot;
152: amap->am_nused++;
153: }
154: amap->am_anon[slot] = anon;
155: UVMHIST_LOG(maphist,
156: "<- done (amap=%p, offset=0x%lx, anon=%p, rep=%ld)",
157: amap, offset, anon, replace);
158: }
159:
160: /*
161: * amap_unadd: remove a page from an amap
162: *
163: * => caller must lock amap
164: */
165: AMAP_INLINE void
166: amap_unadd(aref, offset)
167: struct vm_aref *aref;
168: vaddr_t offset;
169: {
170: int ptr, slot;
171: struct vm_amap *amap = aref->ar_amap;
172: UVMHIST_FUNC("amap_unadd"); UVMHIST_CALLED(maphist);
173:
174: AMAP_B2SLOT(slot, offset);
175: slot += aref->ar_pageoff;
176:
177: if (slot >= amap->am_nslot)
178: panic("amap_unadd: offset out of range");
179:
180: if (amap->am_anon[slot] == NULL)
181: panic("amap_unadd: nothing there");
182:
183: amap->am_anon[slot] = NULL;
184: ptr = amap->am_bckptr[slot];
185:
186: if (ptr != (amap->am_nused - 1)) { /* swap to keep slots contig? */
187: amap->am_slots[ptr] = amap->am_slots[amap->am_nused - 1];
188: amap->am_bckptr[amap->am_slots[ptr]] = ptr; /* back link */
189: }
190: amap->am_nused--;
191: UVMHIST_LOG(maphist, "<- done (amap=%p, slot=%ld)", amap, slot,0, 0);
192: }
193:
194: /*
195: * amap_ref: gain a reference to an amap
196: *
197: * => amap must not be locked (we will lock)
198: * => "offset" and "len" are in units of pages
199: * => called at fork time to gain the child's reference
200: */
201: AMAP_INLINE void
202: amap_ref(amap, offset, len, flags)
203: struct vm_amap *amap;
204: vaddr_t offset;
205: vsize_t len;
206: int flags;
207: {
208: UVMHIST_FUNC("amap_ref"); UVMHIST_CALLED(maphist);
209:
210: amap->am_ref++;
211: if (flags & AMAP_SHARED)
212: amap->am_flags |= AMAP_SHARED;
213: #ifdef UVM_AMAP_PPREF
214: if (amap->am_ppref == NULL && (flags & AMAP_REFALL) == 0 &&
215: len != amap->am_nslot)
216: amap_pp_establish(amap);
217: if (amap->am_ppref && amap->am_ppref != PPREF_NONE) {
218: if (flags & AMAP_REFALL)
219: amap_pp_adjref(amap, 0, amap->am_nslot, 1);
220: else
221: amap_pp_adjref(amap, offset, len, 1);
222: }
223: #endif
224: UVMHIST_LOG(maphist,"<- done! amap=%p", amap, 0, 0, 0);
225: }
226:
227: /*
228: * amap_unref: remove a reference to an amap
229: *
230: * => caller must remove all pmap-level references to this amap before
231: * dropping the reference
232: * => called from uvm_unmap_detach [only] ... note that entry is no
233: * longer part of a map and thus has no need for locking
234: * => amap must be unlocked (we will lock it).
235: */
236: AMAP_INLINE void
237: amap_unref(amap, offset, len, all)
238: struct vm_amap *amap;
239: vaddr_t offset;
240: vsize_t len;
241: boolean_t all;
242: {
243: UVMHIST_FUNC("amap_unref"); UVMHIST_CALLED(maphist);
244:
245: UVMHIST_LOG(maphist," amap=%p refs=%ld, nused=%ld",
246: amap, amap->am_ref, amap->am_nused, 0);
247:
248: /*
249: * if we are the last reference, free the amap and return.
250: */
251:
252: if (amap->am_ref-- == 1) {
253: amap_wipeout(amap); /* drops final ref and frees */
254: UVMHIST_LOG(maphist,"<- done (was last ref)!", 0, 0, 0, 0);
255: return; /* no need to unlock */
256: }
257:
258: /*
259: * otherwise just drop the reference count(s)
260: */
261: if (amap->am_ref == 1 && (amap->am_flags & AMAP_SHARED) != 0)
262: amap->am_flags &= ~AMAP_SHARED; /* clear shared flag */
263: #ifdef UVM_AMAP_PPREF
264: if (amap->am_ppref == NULL && all == 0 && len != amap->am_nslot)
265: amap_pp_establish(amap);
266: if (amap->am_ppref && amap->am_ppref != PPREF_NONE) {
267: if (all)
268: amap_pp_adjref(amap, 0, amap->am_nslot, -1);
269: else
270: amap_pp_adjref(amap, offset, len, -1);
271: }
272: #endif
273:
274: UVMHIST_LOG(maphist,"<- done!", 0, 0, 0, 0);
275: }
276:
277: #endif /* defined(UVM_AMAP_INLINE) || defined(UVM_AMAP_C) */
278:
279: #endif /* _UVM_UVM_AMAP_I_H_ */
CVSweb