uvm_page.h revision 1.73 1 /* $NetBSD: uvm_page.h,v 1.73 2011/06/12 03:36:03 rmind 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_page.h 7.3 (Berkeley) 4/21/91
37 * from: Id: uvm_page.h,v 1.1.2.6 1998/02/04 02:31:42 chuck 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_PAGE_H_
65 #define _UVM_UVM_PAGE_H_
66
67 /*
68 * uvm_page.h
69 */
70
71 /*
72 * Resident memory system definitions.
73 */
74
75 /*
76 * Management of resident (logical) pages.
77 *
78 * A small structure is kept for each resident
79 * page, indexed by page number. Each structure
80 * is an element of several lists:
81 *
82 * A red-black tree rooted with the containing
83 * object is used to quickly perform object+
84 * offset lookups
85 *
86 * A list of all pages for a given object,
87 * so they can be quickly deactivated at
88 * time of deallocation.
89 *
90 * An ordered list of pages due for pageout.
91 *
92 * In addition, the structure contains the object
93 * and offset to which this page belongs (for pageout),
94 * and sundry status bits.
95 *
96 * Fields in this structure are locked either by the lock on the
97 * object that the page belongs to (O) or by the lock on the page
98 * queues (P) [or both].
99 */
100
101 /*
102 * locking note: the mach version of this data structure had bit
103 * fields for the flags, and the bit fields were divided into two
104 * items (depending on who locked what). some time, in BSD, the bit
105 * fields were dumped and all the flags were lumped into one short.
106 * that is fine for a single threaded uniprocessor OS, but bad if you
107 * want to actual make use of locking. so, we've separated things
108 * back out again.
109 *
110 * note the page structure has no lock of its own.
111 */
112
113 #include <uvm/uvm_extern.h>
114 #include <uvm/uvm_pglist.h>
115
116 #include <sys/rbtree.h>
117
118 struct vm_page {
119 struct rb_node rb_node; /* tree of pages in obj (O) */
120
121 union {
122 TAILQ_ENTRY(vm_page) queue;
123 LIST_ENTRY(vm_page) list;
124 } pageq; /* queue info for FIFO
125 * queue or free list (P) */
126 union {
127 TAILQ_ENTRY(vm_page) queue;
128 LIST_ENTRY(vm_page) list;
129 } listq; /* pages in same object (O)*/
130
131 struct vm_anon *uanon; /* anon (O,P) */
132 struct uvm_object *uobject; /* object (O,P) */
133 voff_t offset; /* offset into object (O,P) */
134 uint16_t flags; /* object flags [O] */
135 uint16_t loan_count; /* number of active loans
136 * to read: [O or P]
137 * to modify: [O _and_ P] */
138 uint16_t wire_count; /* wired down map refs [P] */
139 uint16_t pqflags; /* page queue flags [P] */
140 paddr_t phys_addr; /* physical address of page */
141
142 #ifdef __HAVE_VM_PAGE_MD
143 struct vm_page_md mdpage; /* pmap-specific data */
144 #endif
145
146 #if defined(UVM_PAGE_TRKOWN)
147 /* debugging fields to track page ownership */
148 pid_t owner; /* proc that set PG_BUSY */
149 lwpid_t lowner; /* lwp that set PG_BUSY */
150 const char *owner_tag; /* why it was set busy */
151 #endif
152 };
153
154 /*
155 * These are the flags defined for vm_page.
156 */
157
158 /*
159 * locking rules:
160 * PG_ ==> locked by object lock
161 * PQ_ ==> lock by page queue lock
162 * PQ_FREE is locked by free queue lock and is mutex with all other PQs
163 *
164 * PG_ZERO is used to indicate that a page has been pre-zero'd. This flag
165 * is only set when the page is on no queues, and is cleared when the page
166 * is placed on the free list.
167 */
168
169 #define PG_BUSY 0x0001 /* page is locked */
170 #define PG_WANTED 0x0002 /* someone is waiting for page */
171 #define PG_TABLED 0x0004 /* page is in VP table */
172 #define PG_CLEAN 0x0008 /* page has not been modified */
173 #define PG_PAGEOUT 0x0010 /* page to be freed for pagedaemon */
174 #define PG_RELEASED 0x0020 /* page to be freed when unbusied */
175 #define PG_FAKE 0x0040 /* page is not yet initialized */
176 #define PG_RDONLY 0x0080 /* page must be mapped read-only */
177 #define PG_ZERO 0x0100 /* page is pre-zero'd */
178 #define PG_MARKER 0x0200 /* dummy marker page */
179
180 #define PG_PAGER1 0x1000 /* pager-specific flag */
181
182 #define UVM_PGFLAGBITS \
183 "\20\1BUSY\2WANTED\3TABLED\4CLEAN\5PAGEOUT\6RELEASED\7FAKE\10RDONLY" \
184 "\11ZERO\12MARKER\15PAGER1"
185
186 #define PQ_FREE 0x0001 /* page is on free list */
187 #define PQ_ANON 0x0002 /* page is part of an anon, rather
188 than an uvm_object */
189 #define PQ_AOBJ 0x0004 /* page is part of an anonymous
190 uvm_object */
191 #define PQ_SWAPBACKED (PQ_ANON|PQ_AOBJ)
192 #define PQ_READAHEAD 0x0008 /* read-ahead but has not been "hit" yet */
193
194 #define PQ_PRIVATE1 0x0100
195 #define PQ_PRIVATE2 0x0200
196 #define PQ_PRIVATE3 0x0400
197 #define PQ_PRIVATE4 0x0800
198 #define PQ_PRIVATE5 0x1000
199 #define PQ_PRIVATE6 0x2000
200 #define PQ_PRIVATE7 0x4000
201 #define PQ_PRIVATE8 0x8000
202
203 #define UVM_PQFLAGBITS \
204 "\20\1FREE\2ANON\3AOBJ\4READAHEAD" \
205 "\11PRIVATE1\12PRIVATE2\13PRIVATE3\14PRIVATE4" \
206 "\15PRIVATE5\16PRIVATE6\17PRIVATE7\20PRIVATE8"
207
208 /*
209 * physical memory layout structure
210 *
211 * MD vmparam.h must #define:
212 * VM_PHYSEG_MAX = max number of physical memory segments we support
213 * (if this is "1" then we revert to a "contig" case)
214 * VM_PHYSSEG_STRAT: memory sort/search options (for VM_PHYSEG_MAX > 1)
215 * - VM_PSTRAT_RANDOM: linear search (random order)
216 * - VM_PSTRAT_BSEARCH: binary search (sorted by address)
217 * - VM_PSTRAT_BIGFIRST: linear search (sorted by largest segment first)
218 * - others?
219 * XXXCDC: eventually we should purge all left-over global variables...
220 */
221 #define VM_PSTRAT_RANDOM 1
222 #define VM_PSTRAT_BSEARCH 2
223 #define VM_PSTRAT_BIGFIRST 3
224
225 /*
226 * vm_physseg: describes one segment of physical memory
227 */
228 struct vm_physseg {
229 paddr_t start; /* PF# of first page in segment */
230 paddr_t end; /* (PF# of last page in segment) + 1 */
231 paddr_t avail_start; /* PF# of first free page in segment */
232 paddr_t avail_end; /* (PF# of last free page in segment) +1 */
233 struct vm_page *pgs; /* vm_page structures (from start) */
234 struct vm_page *lastpg; /* vm_page structure for end */
235 int free_list; /* which free list they belong on */
236 u_int start_hint; /* start looking for free pages here */
237 /* protected by uvm_fpageqlock */
238 #ifdef __HAVE_PMAP_PHYSSEG
239 struct pmap_physseg pmseg; /* pmap specific (MD) data */
240 #endif
241 };
242
243 #ifdef _KERNEL
244
245 /*
246 * globals
247 */
248
249 extern bool vm_page_zero_enable;
250
251 /*
252 * physical memory config is stored in vm_physmem.
253 */
254
255 #define VM_PHYSMEM_PTR(i) (&vm_physmem[i])
256 #define VM_PHYSMEM_PTR_SWAP(i, j) \
257 do { vm_physmem[(i)] = vm_physmem[(j)]; } while (0)
258
259 extern struct vm_physseg vm_physmem[VM_PHYSSEG_MAX];
260 extern int vm_nphysseg;
261
262 /*
263 * prototypes: the following prototypes define the interface to pages
264 */
265
266 void uvm_page_init(vaddr_t *, vaddr_t *);
267 #if defined(UVM_PAGE_TRKOWN)
268 void uvm_page_own(struct vm_page *, const char *);
269 #endif
270 #if !defined(PMAP_STEAL_MEMORY)
271 bool uvm_page_physget(paddr_t *);
272 #endif
273 void uvm_page_recolor(int);
274 void uvm_pageidlezero(void);
275
276 void uvm_pageactivate(struct vm_page *);
277 vaddr_t uvm_pageboot_alloc(vsize_t);
278 void uvm_pagecopy(struct vm_page *, struct vm_page *);
279 void uvm_pagedeactivate(struct vm_page *);
280 void uvm_pagedequeue(struct vm_page *);
281 void uvm_pageenqueue(struct vm_page *);
282 void uvm_pagefree(struct vm_page *);
283 void uvm_page_unbusy(struct vm_page **, int);
284 struct vm_page *uvm_pagelookup(struct uvm_object *, voff_t);
285 void uvm_pageunwire(struct vm_page *);
286 void uvm_pagewire(struct vm_page *);
287 void uvm_pagezero(struct vm_page *);
288 bool uvm_pageismanaged(paddr_t);
289 bool uvm_page_locked_p(struct vm_page *);
290
291 int uvm_page_lookup_freelist(struct vm_page *);
292
293 int vm_physseg_find(paddr_t, int *);
294 struct vm_page *uvm_phys_to_vm_page(paddr_t);
295 paddr_t uvm_vm_page_to_phys(const struct vm_page *);
296
297 /*
298 * macros
299 */
300
301 #define UVM_PAGE_TREE_PENALTY 4 /* XXX: a guess */
302
303 #define VM_PAGE_TO_PHYS(entry) uvm_vm_page_to_phys(entry)
304
305 #ifdef __HAVE_VM_PAGE_MD
306 #define VM_PAGE_TO_MD(pg) (&(pg)->mdpage)
307 #endif
308
309 /*
310 * Compute the page color bucket for a given page.
311 */
312 #define VM_PGCOLOR_BUCKET(pg) \
313 (atop(VM_PAGE_TO_PHYS((pg))) & uvmexp.colormask)
314
315 #define PHYS_TO_VM_PAGE(pa) uvm_phys_to_vm_page(pa)
316
317 #define VM_PAGE_IS_FREE(entry) ((entry)->pqflags & PQ_FREE)
318 #define VM_FREE_PAGE_TO_CPU(pg) ((struct uvm_cpu *)((uintptr_t)pg->offset))
319
320 #ifdef DEBUG
321 void uvm_pagezerocheck(struct vm_page *);
322 #endif /* DEBUG */
323
324 #endif /* _KERNEL */
325
326 #endif /* _UVM_UVM_PAGE_H_ */
327