1 /* $NetBSD: uvm_page.h,v 1.71 2011/02/02 15:25:27 chuck 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@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_pagewait(struct vm_page *, int); 287 void uvm_pagewake(struct vm_page *); 288 void uvm_pagewire(struct vm_page *); 289 void uvm_pagezero(struct vm_page *); 290 bool uvm_pageismanaged(paddr_t); 291 292 int uvm_page_lookup_freelist(struct vm_page *); 293 294 int vm_physseg_find(paddr_t, int *); 295 struct vm_page *uvm_phys_to_vm_page(paddr_t); 296 paddr_t uvm_vm_page_to_phys(const struct vm_page *); 297 298 /* 299 * macros 300 */ 301 302 #define UVM_PAGE_TREE_PENALTY 4 /* XXX: a guess */ 303 304 #define VM_PAGE_TO_PHYS(entry) uvm_vm_page_to_phys(entry) 305 306 #ifdef __HAVE_VM_PAGE_MD 307 #define VM_PAGE_TO_MD(pg) (&(pg)->mdpage) 308 #endif 309 310 /* 311 * Compute the page color bucket for a given page. 312 */ 313 #define VM_PGCOLOR_BUCKET(pg) \ 314 (atop(VM_PAGE_TO_PHYS((pg))) & uvmexp.colormask) 315 316 #define PHYS_TO_VM_PAGE(pa) uvm_phys_to_vm_page(pa) 317 318 #define VM_PAGE_IS_FREE(entry) ((entry)->pqflags & PQ_FREE) 319 #define VM_FREE_PAGE_TO_CPU(pg) ((struct uvm_cpu *)((uintptr_t)pg->offset)) 320 321 #ifdef DEBUG 322 void uvm_pagezerocheck(struct vm_page *); 323 #endif /* DEBUG */ 324 325 #endif /* _KERNEL */ 326 327 #endif /* _UVM_UVM_PAGE_H_ */ 328