uvm_page.h revision 1.73.2.10
1 /* $NetBSD: uvm_page.h,v 1.73.2.10 2012/04/17 00:09:00 yamt 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 #include <uvm/uvm_extern.h> 68 #include <uvm/uvm_pglist.h> 69 70 /* 71 * Management of resident (logical) pages. 72 * 73 * Each resident page has a vm_page structure, indexed by page number. 74 * There are several lists in the structure: 75 * 76 * - A radix tree rooted with the containing object is used to 77 * quickly perform object+offset lookups. 78 * - An ordered list of pages due for pageout. 79 * 80 * In addition, the structure contains the object and offset to which 81 * this page belongs (for pageout) and sundry status bits. 82 * 83 * Note that the page structure has no lock of its own. The page is 84 * generally protected by its owner's lock (UVM object or amap/anon). 85 * It should be noted that UVM has to serialize pmap(9) operations on 86 * the managed pages, e.g. for pmap_enter() calls. Hence, the lock 87 * order is as follows: 88 * 89 * [vmpage-owner-lock] -> 90 * any pmap locks (e.g. PV hash lock) 91 * 92 * Since the kernel is always self-consistent, no serialization is 93 * required for unmanaged mappings, e.g. for pmap_kenter_pa() calls. 94 * 95 * Field markings and the corresponding locks: 96 * 97 * o: page owner's lock (UVM object or amap/anon) 98 * p: lock on the page queues 99 * o|p: either lock can be acquired 100 * o&p: both locks are required 101 * ?: locked by pmap or assumed page owner's lock 102 * 103 * UVM and pmap(9) may use uvm_page_locked_p() to assert whether the 104 * page owner's lock is acquired. 105 */ 106 107 struct vm_page { 108 union { 109 TAILQ_ENTRY(vm_page) queue; 110 LIST_ENTRY(vm_page) list; 111 } pageq; /* p: queue info for FIFO 112 * queue or free list */ 113 114 union { 115 struct { 116 struct vm_anon *o_anon; /* o,p: anon */ 117 struct uvm_object *o_object; /* o,p: object */ 118 } owner; 119 #define uanon u.owner.o_anon 120 #define uobject u.owner.o_object 121 LIST_ENTRY(vm_page) cpulist; 122 } u; 123 voff_t offset; /* o,p: offset into object */ 124 uint16_t flags; /* o: object flags */ 125 uint16_t loan_count; /* number of active loans 126 * o|p: for reading 127 * o&p: for modification */ 128 uint16_t wire_count; /* p: wired down map refs */ 129 uint16_t pqflags; /* p: page queue flags */ 130 paddr_t phys_addr; /* physical address of page */ 131 132 #ifdef __HAVE_VM_PAGE_MD 133 struct vm_page_md mdpage; /* ?: pmap-specific data */ 134 #endif 135 136 #if defined(UVM_PAGE_TRKOWN) 137 /* debugging fields to track page ownership */ 138 pid_t owner; /* proc that set PG_BUSY */ 139 lwpid_t lowner; /* lwp that set PG_BUSY */ 140 const char *owner_tag; /* why it was set busy */ 141 #endif 142 }; 143 144 /* 145 * These are the flags defined for vm_page. 146 */ 147 148 /* 149 * locking rules: 150 * PG_ ==> locked by object lock 151 * PQ_ ==> lock by page queue lock 152 * PQ_FREE is locked by free queue lock and is mutex with all other PQs 153 * 154 * PG_ZERO is used to indicate that a page has been pre-zero'd. This flag 155 * is only set when the page is on no queues, and is cleared when the page 156 * is placed on the free list. 157 * 158 * PG_RDONLY is used to indicate that the page should not be mapped writably. 159 * typically they are set by pgo_get to inform the fault handler. 160 * 161 * if you want to renumber PG_CLEAN and PG_DIRTY, check __CTASSERTs in 162 * uvm_page_status.c first. 163 */ 164 165 #define PG_CLEAN 0x0001 /* page is known clean */ 166 #define PG_DIRTY 0x0002 /* page is known dirty */ 167 #define PG_BUSY 0x0004 /* page is locked */ 168 #define PG_WANTED 0x0008 /* someone is waiting for page */ 169 #define PG_PAGEOUT 0x0010 /* page to be freed for pagedaemon */ 170 #define PG_RELEASED 0x0020 /* page to be freed when unbusied */ 171 #define PG_FAKE 0x0040 /* page is not yet initialized */ 172 #define PG_RDONLY 0x0080 /* page must be mapped read-only */ 173 #define PG_ZERO 0x0100 /* page is pre-zero'd */ 174 #define PG_TABLED 0x0200 /* page is in VP table */ 175 176 #define PG_PAGER1 0x1000 /* pager-specific flag */ 177 #define PG_PAGER2 0x2000 /* pager-specific flag */ 178 179 #define UVM_PGFLAGBITS \ 180 "\20\1CLEAN\2DIRTY\3BUSY\4WANTED" \ 181 "\5PAGEOUT\6RELEASED\7FAKE\10RDONLY" \ 182 "\11ZERO\12TABLED" \ 183 "\15PAGER1\16PAGER2" 184 185 #define PQ_FREE 0x0001 /* page is on free list */ 186 #define PQ_ANON 0x0002 /* page is part of an anon, rather 187 than an uvm_object */ 188 #define PQ_AOBJ 0x0004 /* page is part of an anonymous 189 uvm_object */ 190 #define PQ_SWAPBACKED (PQ_ANON|PQ_AOBJ) 191 #define PQ_READAHEAD 0x0008 /* read-ahead but has not been "hit" yet */ 192 #define PQ_FILE 0x0010 /* file backed (non-anonymous) */ 193 #define PQ_STAT (PQ_ANON|PQ_AOBJ|PQ_FILE) 194 195 #define PQ_PRIVATE1 0x0100 196 #define PQ_PRIVATE2 0x0200 197 #define PQ_PRIVATE3 0x0400 198 #define PQ_PRIVATE4 0x0800 199 #define PQ_PRIVATE5 0x1000 200 #define PQ_PRIVATE6 0x2000 201 #define PQ_PRIVATE7 0x4000 202 #define PQ_PRIVATE8 0x8000 203 204 #define UVM_PQFLAGBITS \ 205 "\20\1FREE\2ANON\3AOBJ\4READAHEAD\5FILE" \ 206 "\11PRIVATE1\12PRIVATE2\13PRIVATE3\14PRIVATE4" \ 207 "\15PRIVATE5\16PRIVATE6\17PRIVATE7\20PRIVATE8" 208 209 /* 210 * physical memory layout structure 211 * 212 * MD vmparam.h must #define: 213 * VM_PHYSEG_MAX = max number of physical memory segments we support 214 * (if this is "1" then we revert to a "contig" case) 215 * VM_PHYSSEG_STRAT: memory sort/search options (for VM_PHYSEG_MAX > 1) 216 * - VM_PSTRAT_RANDOM: linear search (random order) 217 * - VM_PSTRAT_BSEARCH: binary search (sorted by address) 218 * - VM_PSTRAT_BIGFIRST: linear search (sorted by largest segment first) 219 * - others? 220 * XXXCDC: eventually we should purge all left-over global variables... 221 */ 222 #define VM_PSTRAT_RANDOM 1 223 #define VM_PSTRAT_BSEARCH 2 224 #define VM_PSTRAT_BIGFIRST 3 225 226 /* 227 * vm_physseg: describes one segment of physical memory 228 */ 229 struct vm_physseg { 230 paddr_t start; /* PF# of first page in segment */ 231 paddr_t end; /* (PF# of last page in segment) + 1 */ 232 paddr_t avail_start; /* PF# of first free page in segment */ 233 paddr_t avail_end; /* (PF# of last free page in segment) +1 */ 234 struct vm_page *pgs; /* vm_page structures (from start) */ 235 struct vm_page *lastpg; /* vm_page structure for end */ 236 int free_list; /* which free list they belong on */ 237 u_int start_hint; /* start looking for free pages here */ 238 /* protected by uvm_fpageqlock */ 239 #ifdef __HAVE_PMAP_PHYSSEG 240 struct pmap_physseg pmseg; /* pmap specific (MD) data */ 241 #endif 242 }; 243 244 #ifdef _KERNEL 245 246 /* 247 * globals 248 */ 249 250 extern bool vm_page_zero_enable; 251 252 /* 253 * physical memory config is stored in vm_physmem. 254 */ 255 256 #define VM_PHYSMEM_PTR(i) (&vm_physmem[i]) 257 #define VM_PHYSMEM_PTR_SWAP(i, j) \ 258 do { vm_physmem[(i)] = vm_physmem[(j)]; } while (0) 259 260 extern struct vm_physseg vm_physmem[VM_PHYSSEG_MAX]; 261 extern int vm_nphysseg; 262 263 /* 264 * prototypes: the following prototypes define the interface to pages 265 */ 266 267 void uvm_page_init(vaddr_t *, vaddr_t *); 268 #if defined(UVM_PAGE_TRKOWN) 269 void uvm_page_own(struct vm_page *, const char *); 270 #endif 271 #if !defined(PMAP_STEAL_MEMORY) 272 bool uvm_page_physget(paddr_t *); 273 #endif 274 void uvm_page_recolor(int); 275 void uvm_pageidlezero(void); 276 277 void uvm_pageactivate(struct vm_page *); 278 vaddr_t uvm_pageboot_alloc(vsize_t); 279 void uvm_pagecopy(struct vm_page *, struct vm_page *); 280 void uvm_pagedeactivate(struct vm_page *); 281 void uvm_pagedequeue(struct vm_page *); 282 void uvm_pageenqueue(struct vm_page *); 283 void uvm_pagefree(struct vm_page *); 284 void uvm_page_unbusy(struct vm_page **, int); 285 struct vm_page *uvm_pagelookup(struct uvm_object *, voff_t); 286 void uvm_pageunwire(struct vm_page *); 287 void uvm_pagewire(struct vm_page *); 288 void uvm_pagezero(struct vm_page *); 289 bool uvm_pageismanaged(paddr_t); 290 unsigned int uvm_pagegetdirty(struct vm_page *); 291 void uvm_pagemarkdirty(struct vm_page *, unsigned int); 292 bool uvm_pagecheckdirty(struct vm_page *, bool); 293 bool uvm_pagereadonly_p(struct vm_page *); 294 bool uvm_page_locked_p(struct vm_page *); 295 kmutex_t *uvm_page_getlock(struct vm_page *); 296 bool uvm_page_samelock_p(struct vm_page *, struct vm_page *); 297 298 struct uvm_cpu; 299 struct uvm_cpu *uvm_cpu_get(void); 300 void uvm_cpu_put(struct uvm_cpu *); 301 302 /* 303 * page dirtiness status for uvm_pagegetdirty and uvm_pagemarkdirty 304 * 305 * UNKNOWN means that we need to consult pmap to know if the page is 306 * dirty or not. 307 * basically, UVM_PAGE_STATUS_CLEAN implies that the page has no writable 308 * mapping. 309 * 310 * if you want to renumber these, check __CTASSERTs in 311 * uvm_page_status.c first. 312 */ 313 #define UVM_PAGE_STATUS_UNKNOWN 0 314 #define UVM_PAGE_STATUS_CLEAN 1 315 #define UVM_PAGE_STATUS_DIRTY 2 316 #define UVM_PAGE_NUM_STATUS 3 317 318 int uvm_page_lookup_freelist(struct vm_page *); 319 320 int vm_physseg_find(paddr_t, int *); 321 struct vm_page *uvm_phys_to_vm_page(paddr_t); 322 paddr_t uvm_vm_page_to_phys(const struct vm_page *); 323 324 /* 325 * macros 326 */ 327 328 #define VM_PAGE_TO_PHYS(entry) uvm_vm_page_to_phys(entry) 329 330 #ifdef __HAVE_VM_PAGE_MD 331 #define VM_PAGE_TO_MD(pg) (&(pg)->mdpage) 332 #endif 333 334 /* 335 * Compute the page color bucket for a given page. 336 */ 337 #define VM_PGCOLOR_BUCKET(pg) \ 338 (atop(VM_PAGE_TO_PHYS((pg))) & uvmexp.colormask) 339 340 #define PHYS_TO_VM_PAGE(pa) uvm_phys_to_vm_page(pa) 341 342 #define VM_PAGE_IS_FREE(entry) ((entry)->pqflags & PQ_FREE) 343 #define VM_FREE_PAGE_TO_CPU(pg) ((struct uvm_cpu *)((uintptr_t)pg->offset)) 344 345 #ifdef DEBUG 346 void uvm_pagezerocheck(struct vm_page *); 347 #endif /* DEBUG */ 348 349 #endif /* _KERNEL */ 350 351 #endif /* _UVM_UVM_PAGE_H_ */ 352
Indexes created Wed Oct 22 13:09:56 GMT 2025