1 /* $OpenBSD: uvm_page.h,v 1.71 2024/05/13 01:15:53 jsg Exp $ */
2 /* $NetBSD: uvm_page.h,v 1.19 2000/12/28 08:24:55 chs Exp $ */
3
4 /*
5 * Copyright (c) 1997 Charles D. Cranor and Washington University.
6 * Copyright (c) 1991, 1993, The Regents of the University of California.
7 *
8 * All rights reserved.
9 *
10 * This code is derived from software contributed to Berkeley by
11 * The Mach Operating System project at Carnegie-Mellon University.
12 *
13 * Redistribution and use in source and binary forms, with or without
14 * modification, are permitted provided that the following conditions
15 * are met:
16 * 1. Redistributions of source code must retain the above copyright
17 * notice, this list of conditions and the following disclaimer.
18 * 2. Redistributions in binary form must reproduce the above copyright
19 * notice, this list of conditions and the following disclaimer in the
20 * documentation and/or other materials provided with the distribution.
21 * 3. Neither the name of the University nor the names of its contributors
22 * may be used to endorse or promote products derived from this software
23 * without specific prior written permission.
24 *
25 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
26 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
27 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
28 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
29 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
30 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
31 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
32 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
33 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
34 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
35 * SUCH DAMAGE.
36 *
37 * @(#)vm_page.h 7.3 (Berkeley) 4/21/91
38 * from: Id: uvm_page.h,v 1.1.2.6 1998/02/04 02:31:42 chuck Exp
39 *
40 *
41 * Copyright (c) 1987, 1990 Carnegie-Mellon University.
42 * All rights reserved.
43 *
44 * Permission to use, copy, modify and distribute this software and
45 * its documentation is hereby granted, provided that both the copyright
46 * notice and this permission notice appear in all copies of the
47 * software, derivative works or modified versions, and any portions
48 * thereof, and that both notices appear in supporting documentation.
49 *
50 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
51 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
52 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
53 *
54 * Carnegie Mellon requests users of this software to return to
55 *
56 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
57 * School of Computer Science
58 * Carnegie Mellon University
59 * Pittsburgh PA 15213-3890
60 *
61 * any improvements or extensions that they make and grant Carnegie the
62 * rights to redistribute these changes.
63 */
64
65 #ifndef _UVM_UVM_PAGE_H_
66 #define _UVM_UVM_PAGE_H_
67
68 /*
69 * uvm_page.h
70 */
71
72 /*
73 * Resident memory system definitions.
74 */
75
76 /*
77 * Management of resident (logical) pages.
78 *
79 * A small structure is kept for each resident
80 * page, indexed by page number. Each structure
81 * contains a list used for manipulating pages, and
82 * a tree structure for in object/offset lookups
83 *
84 * In addition, the structure contains the object
85 * and offset to which this page belongs (for pageout),
86 * and sundry status bits.
87 *
88 * Fields in this structure are possibly locked by the lock on the page
89 * queues (P).
90 */
91
92 TAILQ_HEAD(pglist, vm_page);
93
94 struct vm_page {
95 TAILQ_ENTRY(vm_page) pageq; /* queue info for FIFO
96 * queue or free list (P) */
97 RBT_ENTRY(vm_page) objt; /* object tree */
98
99 struct vm_anon *uanon; /* anon (P) */
100 struct uvm_object *uobject; /* object (P) */
101 voff_t offset; /* offset into object (P) */
102
103 u_int pg_flags; /* object flags [P] */
104
105 u_int pg_version; /* version count */
106 u_int wire_count; /* wired down map refs [P] */
107
108 paddr_t phys_addr; /* physical address of page */
109 psize_t fpgsz; /* free page range size */
110
111 struct vm_page_md mdpage; /* pmap-specific data */
112
113 #if defined(UVM_PAGE_TRKOWN)
114 /* debugging fields to track page ownership */
115 pid_t owner; /* thread that set PG_BUSY */
116 char *owner_tag; /* why it was set busy */
117 #endif
118 };
119
120 /*
121 * These are the flags defined for vm_page.
122 *
123 * Note: PG_FILLED and PG_DIRTY are added for the filesystems.
124 */
125
126 /*
127 * locking rules:
128 * PQ_ ==> lock by page queue lock
129 * PQ_FREE is locked by free queue lock and is mutex with all other PQs
130 * pg_flags may only be changed using the atomic operations.
131 *
132 * PG_ZERO is used to indicate that a page has been pre-zero'd. This flag
133 * is only set when the page is on no queues, and is cleared when the page
134 * is placed on the free list.
135 */
136
137 #define PG_BUSY 0x00000001 /* page is locked */
138 #define PG_WANTED 0x00000002 /* someone is waiting for page */
139 #define PG_TABLED 0x00000004 /* page is in VP table */
140 #define PG_CLEAN 0x00000008 /* page has not been modified */
141 #define PG_CLEANCHK 0x00000010 /* clean bit has been checked */
142 #define PG_RELEASED 0x00000020 /* page released while paging */
143 #define PG_FAKE 0x00000040 /* page is not yet initialized */
144 #define PG_RDONLY 0x00000080 /* page must be mapped read-only */
145 #define PG_ZERO 0x00000100 /* page is pre-zero'd */
146 #define PG_DEV 0x00000200 /* page is in device space, lay off */
147
148 #define PG_PAGER1 0x00001000 /* pager-specific flag */
149 #define PG_MASK 0x0000ffff
150
151 #define PQ_FREE 0x00010000 /* page is on free list */
152 #define PQ_INACTIVE 0x00020000 /* page is in inactive list */
153 #define PQ_ACTIVE 0x00040000 /* page is in active list */
154 #define PQ_ANON 0x00100000 /* page is part of an anon, rather
155 than an uvm_object */
156 #define PQ_AOBJ 0x00200000 /* page is part of an anonymous
157 uvm_object */
158 #define PQ_SWAPBACKED (PQ_ANON|PQ_AOBJ)
159 #define PQ_ENCRYPT 0x00400000 /* page needs {en,de}cryption */
160 #define PQ_MASK 0x00ff0000
161
162 #define PG_PMAP0 0x01000000 /* Used by some pmaps. */
163 #define PG_PMAP1 0x02000000 /* Used by some pmaps. */
164 #define PG_PMAP2 0x04000000 /* Used by some pmaps. */
165 #define PG_PMAP3 0x08000000 /* Used by some pmaps. */
166 #define PG_PMAP4 0x10000000 /* Used by some pmaps. */
167 #define PG_PMAP5 0x20000000 /* Used by some pmaps. */
168 #define PG_PMAPMASK 0x3f000000
169
170 /*
171 * physical memory layout structure
172 *
173 * MD vmparam.h must #define:
174 * VM_PHYSSEG_MAX = max number of physical memory segments we support
175 * (if this is "1" then we revert to a "contig" case)
176 * VM_PHYSSEG_STRAT: memory sort/search options (for VM_PHYSSEG_MAX > 1)
177 * - VM_PSTRAT_RANDOM: linear search (random order)
178 * - VM_PSTRAT_BSEARCH: binary search (sorted by address)
179 * - VM_PSTRAT_BIGFIRST: linear search (sorted by largest segment first)
180 * - others?
181 * XXXCDC: eventually we should purge all left-over global variables...
182 */
183 #define VM_PSTRAT_RANDOM 1
184 #define VM_PSTRAT_BSEARCH 2
185 #define VM_PSTRAT_BIGFIRST 3
186
187 /*
188 * vm_physmemseg: describes one segment of physical memory
189 */
190 struct vm_physseg {
191 paddr_t start; /* PF# of first page in segment */
192 paddr_t end; /* (PF# of last page in segment) + 1 */
193 paddr_t avail_start; /* PF# of first free page in segment */
194 paddr_t avail_end; /* (PF# of last free page in segment) +1 */
195 struct vm_page *pgs; /* vm_page structures (from start) */
196 struct vm_page *lastpg; /* vm_page structure for end */
197 };
198
199 #ifdef _KERNEL
200
201 /*
202 * physical memory config is stored in vm_physmem.
203 */
204
205 extern struct vm_physseg vm_physmem[VM_PHYSSEG_MAX];
206 extern int vm_nphysseg;
207
208 /*
209 * prototypes: the following prototypes define the interface to pages
210 */
211
212 void uvm_page_init(vaddr_t *, vaddr_t *);
213 #if defined(UVM_PAGE_TRKOWN)
214 void uvm_page_own(struct vm_page *, char *);
215 #endif
216 #if !defined(PMAP_STEAL_MEMORY)
217 boolean_t uvm_page_physget(paddr_t *);
218 #endif
219
220 void uvm_pageactivate(struct vm_page *);
221 void uvm_pagedequeue(struct vm_page *);
222 vaddr_t uvm_pageboot_alloc(vsize_t);
223 void uvm_pagecopy(struct vm_page *, struct vm_page *);
224 void uvm_pagedeactivate(struct vm_page *);
225 void uvm_pageclean(struct vm_page *);
226 void uvm_pagefree(struct vm_page *);
227 void uvm_page_unbusy(struct vm_page **, int);
228 struct vm_page *uvm_pagelookup(struct uvm_object *, voff_t);
229 void uvm_pageunwire(struct vm_page *);
230 void uvm_pagewait(struct vm_page *, struct rwlock *, const char *);
231 void uvm_pagewire(struct vm_page *);
232 void uvm_pagezero(struct vm_page *);
233 void uvm_pagealloc_pg(struct vm_page *, struct uvm_object *,
234 voff_t, struct vm_anon *);
235
236 struct uvm_constraint_range; /* XXX move to uvm_extern.h? */
237 psize_t uvm_pagecount(struct uvm_constraint_range*);
238
239 #if VM_PHYSSEG_MAX == 1
240 /*
241 * Inline functions for archs where function calls are expensive.
242 */
243 /*
244 * vm_physseg_find: find vm_physseg structure that belongs to a PA
245 */
246 static inline int
vm_physseg_find(paddr_t pframe,int * offp)247 vm_physseg_find(paddr_t pframe, int *offp)
248 {
249 /* 'contig' case */
250 if (pframe >= vm_physmem[0].start && pframe < vm_physmem[0].end) {
251 if (offp)
252 *offp = pframe - vm_physmem[0].start;
253 return 0;
254 }
255 return -1;
256 }
257
258 /*
259 * PHYS_TO_VM_PAGE: find vm_page for a PA. used by MI code to get vm_pages
260 * back from an I/O mapping (ugh!). used in some MD code as well.
261 */
262 static inline struct vm_page *
PHYS_TO_VM_PAGE(paddr_t pa)263 PHYS_TO_VM_PAGE(paddr_t pa)
264 {
265 paddr_t pf = atop(pa);
266 int off;
267 int psi;
268
269 psi = vm_physseg_find(pf, &off);
270
271 return ((psi == -1) ? NULL : &vm_physmem[psi].pgs[off]);
272 }
273 #else
274 /* if VM_PHYSSEG_MAX > 1 they're not inline, they're in uvm_page.c. */
275 struct vm_page *PHYS_TO_VM_PAGE(paddr_t);
276 int vm_physseg_find(paddr_t, int *);
277 #endif
278
279 /*
280 * macros
281 */
282
283 #define uvm_lock_pageq() mtx_enter(&uvm.pageqlock)
284 #define uvm_unlock_pageq() mtx_leave(&uvm.pageqlock)
285 #define uvm_lock_fpageq() mtx_enter(&uvm.fpageqlock)
286 #define uvm_unlock_fpageq() mtx_leave(&uvm.fpageqlock)
287
288 #define UVM_PAGEZERO_TARGET (uvmexp.free / 8)
289
290 #define VM_PAGE_TO_PHYS(entry) ((entry)->phys_addr)
291
292 #define VM_PAGE_IS_FREE(entry) ((entry)->pg_flags & PQ_FREE)
293
294 #define PADDR_IS_DMA_REACHABLE(paddr) \
295 (dma_constraint.ucr_low <= paddr && dma_constraint.ucr_high > paddr)
296
297 #endif /* _KERNEL */
298
299 #endif /* _UVM_UVM_PAGE_H_ */
300