1 /* $NetBSD: uvm_map.h,v 1.58 2007/07/22 21:07:47 he 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. All advertising materials mentioning features or use of this software 21 * must display the following acknowledgement: 22 * This product includes software developed by Charles D. Cranor, 23 * Washington University, the University of California, Berkeley and 24 * its contributors. 25 * 4. Neither the name of the University nor the names of its contributors 26 * may be used to endorse or promote products derived from this software 27 * without specific prior written permission. 28 * 29 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 30 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 31 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 32 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 33 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 34 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 35 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 36 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 37 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 38 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 39 * SUCH DAMAGE. 40 * 41 * @(#)vm_map.h 8.3 (Berkeley) 3/15/94 42 * from: Id: uvm_map.h,v 1.1.2.3 1998/02/07 01:16:55 chs Exp 43 * 44 * 45 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 46 * All rights reserved. 47 * 48 * Permission to use, copy, modify and distribute this software and 49 * its documentation is hereby granted, provided that both the copyright 50 * notice and this permission notice appear in all copies of the 51 * software, derivative works or modified versions, and any portions 52 * thereof, and that both notices appear in supporting documentation. 53 * 54 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 55 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 56 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 57 * 58 * Carnegie Mellon requests users of this software to return to 59 * 60 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 61 * School of Computer Science 62 * Carnegie Mellon University 63 * Pittsburgh PA 15213-3890 64 * 65 * any improvements or extensions that they make and grant Carnegie the 66 * rights to redistribute these changes. 67 */ 68 69 #ifndef _UVM_UVM_MAP_H_ 70 #define _UVM_UVM_MAP_H_ 71 72 /* 73 * uvm_map.h 74 */ 75 76 #ifdef _KERNEL 77 78 /* 79 * macros 80 */ 81 82 /* 83 * UVM_MAP_CLIP_START: ensure that the entry begins at or after 84 * the starting address, if it doesn't we split the entry. 85 * 86 * => map must be locked by caller 87 */ 88 89 #define UVM_MAP_CLIP_START(MAP,ENTRY,VA,UMR) { \ 90 if ((VA) > (ENTRY)->start) uvm_map_clip_start(MAP,ENTRY,VA,UMR); } 91 92 /* 93 * UVM_MAP_CLIP_END: ensure that the entry ends at or before 94 * the ending address, if it does't we split the entry. 95 * 96 * => map must be locked by caller 97 */ 98 99 #define UVM_MAP_CLIP_END(MAP,ENTRY,VA,UMR) { \ 100 if ((VA) < (ENTRY)->end) uvm_map_clip_end(MAP,ENTRY,VA,UMR); } 101 102 /* 103 * extract flags 104 */ 105 #define UVM_EXTRACT_REMOVE 0x01 /* remove mapping from old map */ 106 #define UVM_EXTRACT_CONTIG 0x02 /* try to keep it contig */ 107 #define UVM_EXTRACT_QREF 0x04 /* use quick refs */ 108 #define UVM_EXTRACT_FIXPROT 0x08 /* set prot to maxprot as we go */ 109 #define UVM_EXTRACT_RESERVED 0x10 /* caller did uvm_map_reserve() */ 110 111 #endif /* _KERNEL */ 112 113 #include <sys/tree.h> 114 #include <sys/pool.h> 115 #include <sys/rwlock.h> 116 #include <sys/mutex.h> 117 #include <sys/condvar.h> 118 119 #include <uvm/uvm_anon.h> 120 121 /* 122 * Address map entries consist of start and end addresses, 123 * a VM object (or sharing map) and offset into that object, 124 * and user-exported inheritance and protection information. 125 * Also included is control information for virtual copy operations. 126 */ 127 struct vm_map_entry { 128 RB_ENTRY(vm_map_entry) rb_entry; /* tree information */ 129 vaddr_t ownspace; /* free space after */ 130 vaddr_t space; /* space in subtree */ 131 struct vm_map_entry *prev; /* previous entry */ 132 struct vm_map_entry *next; /* next entry */ 133 vaddr_t start; /* start address */ 134 vaddr_t end; /* end address */ 135 union { 136 struct uvm_object *uvm_obj; /* uvm object */ 137 struct vm_map *sub_map; /* belongs to another map */ 138 } object; /* object I point to */ 139 voff_t offset; /* offset into object */ 140 int etype; /* entry type */ 141 vm_prot_t protection; /* protection code */ 142 vm_prot_t max_protection; /* maximum protection */ 143 vm_inherit_t inheritance; /* inheritance */ 144 int wired_count; /* can be paged if == 0 */ 145 struct vm_aref aref; /* anonymous overlay */ 146 int advice; /* madvise advice */ 147 #define uvm_map_entry_stop_copy flags 148 u_int8_t flags; /* flags */ 149 150 #define UVM_MAP_KERNEL 0x01 /* kernel map entry */ 151 #define UVM_MAP_KMAPENT 0x02 /* contains map entries */ 152 #define UVM_MAP_FIRST 0x04 /* the first special entry */ 153 #define UVM_MAP_QUANTUM 0x08 /* allocated with 154 * UVM_FLAG_QUANTUM */ 155 #define UVM_MAP_NOMERGE 0x10 /* this entry is not mergable */ 156 157 }; 158 159 #define VM_MAPENT_ISWIRED(entry) ((entry)->wired_count != 0) 160 161 /* 162 * Maps are doubly-linked lists of map entries, kept sorted 163 * by address. A single hint is provided to start 164 * searches again from the last successful search, 165 * insertion, or removal. 166 * 167 * LOCKING PROTOCOL NOTES: 168 * ----------------------- 169 * 170 * VM map locking is a little complicated. There are both shared 171 * and exclusive locks on maps. However, it is sometimes required 172 * to downgrade an exclusive lock to a shared lock, and upgrade to 173 * an exclusive lock again (to perform error recovery). However, 174 * another thread *must not* queue itself to receive an exclusive 175 * lock while before we upgrade back to exclusive, otherwise the 176 * error recovery becomes extremely difficult, if not impossible. 177 * 178 * In order to prevent this scenario, we introduce the notion of 179 * a `busy' map. A `busy' map is read-locked, but other threads 180 * attempting to write-lock wait for this flag to clear before 181 * entering the lock manager. A map may only be marked busy 182 * when the map is write-locked (and then the map must be downgraded 183 * to read-locked), and may only be marked unbusy by the thread 184 * which marked it busy (holding *either* a read-lock or a 185 * write-lock, the latter being gained by an upgrade). 186 * 187 * Access to the map `flags' member is controlled by the `flags_lock' 188 * simple lock. Note that some flags are static (set once at map 189 * creation time, and never changed), and thus require no locking 190 * to check those flags. All flags which are r/w must be set or 191 * cleared while the `flags_lock' is asserted. Additional locking 192 * requirements are: 193 * 194 * VM_MAP_PAGEABLE r/o static flag; no locking required 195 * 196 * VM_MAP_INTRSAFE r/o static flag; no locking required 197 * 198 * VM_MAP_WIREFUTURE r/w; may only be set or cleared when 199 * map is write-locked. may be tested 200 * without asserting `flags_lock'. 201 * 202 * VM_MAP_DYING r/o; set when a vmspace is being 203 * destroyed to indicate that updates 204 * to the pmap can be skipped. 205 * 206 * VM_MAP_TOPDOWN r/o; set when the vmspace is 207 * created if the unspecified map 208 * allocations are to be arranged in 209 * a "top down" manner. 210 */ 211 struct vm_map { 212 struct pmap * pmap; /* Physical map */ 213 krwlock_t lock; /* Non-intrsafe lock */ 214 struct lwp * busy; /* LWP holding map busy */ 215 kmutex_t mutex; /* INTRSAFE lock */ 216 kmutex_t misc_lock; /* Lock for ref_count, cv */ 217 kmutex_t hint_lock; /* lock for hint storage */ 218 kcondvar_t cv; /* For signalling */ 219 int flags; /* flags */ 220 RB_HEAD(uvm_tree, vm_map_entry) rbhead; /* Tree for entries */ 221 struct vm_map_entry header; /* List of entries */ 222 int nentries; /* Number of entries */ 223 vsize_t size; /* virtual size */ 224 int ref_count; /* Reference count */ 225 struct vm_map_entry * hint; /* hint for quick lookups */ 226 struct vm_map_entry * first_free; /* First free space hint */ 227 unsigned int timestamp; /* Version number */ 228 }; 229 230 #if defined(_KERNEL) 231 232 #include <sys/callback.h> 233 234 struct vm_map_kernel { 235 struct vm_map vmk_map; 236 LIST_HEAD(, uvm_kmapent_hdr) vmk_kentry_free; 237 /* Freelist of map entry */ 238 struct vm_map_entry *vmk_merged_entries; 239 /* Merged entries, kept for later splitting */ 240 241 struct callback_head vmk_reclaim_callback; 242 #if !defined(PMAP_MAP_POOLPAGE) 243 struct pool vmk_vacache; /* kva cache */ 244 struct pool_allocator vmk_vacache_allocator; /* ... and its allocator */ 245 #endif 246 }; 247 #endif /* defined(_KERNEL) */ 248 249 #define VM_MAP_IS_KERNEL(map) (vm_map_pmap(map) == pmap_kernel()) 250 251 /* vm_map flags */ 252 #define VM_MAP_PAGEABLE 0x01 /* ro: entries are pageable */ 253 #define VM_MAP_INTRSAFE 0x02 /* ro: interrupt safe map */ 254 #define VM_MAP_WIREFUTURE 0x04 /* rw: wire future mappings */ 255 #define VM_MAP_DYING 0x20 /* rw: map is being destroyed */ 256 #define VM_MAP_TOPDOWN 0x40 /* ro: arrange map top-down */ 257 #define VM_MAP_VACACHE 0x80 /* ro: use kva cache */ 258 #define VM_MAP_WANTVA 0x100 /* rw: want va */ 259 260 #ifdef _KERNEL 261 struct uvm_mapent_reservation { 262 struct vm_map_entry *umr_entries[2]; 263 int umr_nentries; 264 }; 265 #define UMR_EMPTY(umr) ((umr) == NULL || (umr)->umr_nentries == 0) 266 #define UMR_GETENTRY(umr) ((umr)->umr_entries[--(umr)->umr_nentries]) 267 #define UMR_PUTENTRY(umr, ent) \ 268 (umr)->umr_entries[(umr)->umr_nentries++] = (ent) 269 270 struct uvm_map_args { 271 struct vm_map_entry *uma_prev; 272 273 vaddr_t uma_start; 274 vsize_t uma_size; 275 276 struct uvm_object *uma_uobj; 277 voff_t uma_uoffset; 278 279 uvm_flag_t uma_flags; 280 }; 281 #endif /* _KERNEL */ 282 283 /* 284 * globals: 285 */ 286 287 #ifdef _KERNEL 288 289 #include <sys/proc.h> 290 291 #ifdef PMAP_GROWKERNEL 292 extern vaddr_t uvm_maxkaddr; 293 #endif 294 295 /* 296 * protos: the following prototypes define the interface to vm_map 297 */ 298 299 void uvm_map_deallocate(struct vm_map *); 300 301 int uvm_map_clean(struct vm_map *, vaddr_t, vaddr_t, int); 302 void uvm_map_clip_start(struct vm_map *, struct vm_map_entry *, 303 vaddr_t, struct uvm_mapent_reservation *); 304 void uvm_map_clip_end(struct vm_map *, struct vm_map_entry *, 305 vaddr_t, struct uvm_mapent_reservation *); 306 struct vm_map *uvm_map_create(pmap_t, vaddr_t, vaddr_t, int); 307 int uvm_map_extract(struct vm_map *, vaddr_t, vsize_t, 308 struct vm_map *, vaddr_t *, int); 309 struct vm_map_entry * 310 uvm_map_findspace(struct vm_map *, vaddr_t, vsize_t, 311 vaddr_t *, struct uvm_object *, voff_t, vsize_t, int); 312 int uvm_map_inherit(struct vm_map *, vaddr_t, vaddr_t, 313 vm_inherit_t); 314 int uvm_map_advice(struct vm_map *, vaddr_t, vaddr_t, int); 315 void uvm_map_init(void); 316 bool uvm_map_lookup_entry(struct vm_map *, vaddr_t, 317 struct vm_map_entry **); 318 void uvm_map_reference(struct vm_map *); 319 int uvm_map_replace(struct vm_map *, vaddr_t, vaddr_t, 320 struct vm_map_entry *, int); 321 int uvm_map_reserve(struct vm_map *, vsize_t, vaddr_t, vsize_t, 322 vaddr_t *, uvm_flag_t); 323 void uvm_map_setup(struct vm_map *, vaddr_t, vaddr_t, int); 324 void uvm_map_setup_kernel(struct vm_map_kernel *, 325 vaddr_t, vaddr_t, int); 326 struct vm_map_kernel * 327 vm_map_to_kernel(struct vm_map *); 328 int uvm_map_submap(struct vm_map *, vaddr_t, vaddr_t, 329 struct vm_map *); 330 void uvm_unmap1(struct vm_map *, vaddr_t, vaddr_t, int); 331 #define uvm_unmap(map, s, e) uvm_unmap1((map), (s), (e), 0) 332 void uvm_unmap_detach(struct vm_map_entry *,int); 333 void uvm_unmap_remove(struct vm_map *, vaddr_t, vaddr_t, 334 struct vm_map_entry **, struct uvm_mapent_reservation *, 335 int); 336 337 int uvm_map_prepare(struct vm_map *, vaddr_t, vsize_t, 338 struct uvm_object *, voff_t, vsize_t, uvm_flag_t, 339 struct uvm_map_args *); 340 int uvm_map_enter(struct vm_map *, const struct uvm_map_args *, 341 struct vm_map_entry *); 342 343 int uvm_mapent_reserve(struct vm_map *, 344 struct uvm_mapent_reservation *, int, int); 345 void uvm_mapent_unreserve(struct vm_map *, 346 struct uvm_mapent_reservation *); 347 348 vsize_t uvm_mapent_overhead(vsize_t, int); 349 350 int uvm_mapent_trymerge(struct vm_map *, 351 struct vm_map_entry *, int); 352 #define UVM_MERGE_COPYING 1 353 354 bool vm_map_starved_p(struct vm_map *); 355 356 /* 357 * VM map locking operations. 358 */ 359 360 bool vm_map_lock_try(struct vm_map *); 361 void vm_map_lock(struct vm_map *); 362 void vm_map_unlock(struct vm_map *); 363 void vm_map_upgrade(struct vm_map *); 364 void vm_map_unbusy(struct vm_map *); 365 366 /* 367 * vm_map_lock_read: acquire a shared (read) lock on a map. 368 */ 369 370 static inline void 371 vm_map_lock_read(struct vm_map *map) 372 { 373 374 KASSERT((map->flags & VM_MAP_INTRSAFE) == 0); 375 376 rw_enter(&map->lock, RW_READER); 377 } 378 379 /* 380 * vm_map_unlock_read: release a shared lock on a map. 381 */ 382 383 static inline void 384 vm_map_unlock_read(struct vm_map *map) 385 { 386 387 KASSERT((map->flags & VM_MAP_INTRSAFE) == 0); 388 389 rw_exit(&map->lock); 390 } 391 /* 392 * vm_map_downgrade: downgrade an exclusive lock to a shared lock. 393 */ 394 395 static inline void 396 vm_map_downgrade(struct vm_map *map) 397 { 398 399 rw_downgrade(&map->lock); 400 } 401 402 /* 403 * vm_map_busy: mark a map as busy. 404 * 405 * => the caller must hold the map write locked 406 */ 407 408 static inline void 409 vm_map_busy(struct vm_map *map) 410 { 411 412 KASSERT(rw_write_held(&map->lock)); 413 KASSERT(map->busy == NULL); 414 415 map->busy = curlwp; 416 } 417 418 #endif /* _KERNEL */ 419 420 /* 421 * Functions implemented as macros 422 */ 423 #define vm_map_min(map) ((map)->header.end) 424 #define vm_map_max(map) ((map)->header.start) 425 #define vm_map_setmin(map, v) ((map)->header.end = (v)) 426 #define vm_map_setmax(map, v) ((map)->header.start = (v)) 427 428 #define vm_map_pmap(map) ((map)->pmap) 429 430 #endif /* _UVM_UVM_MAP_H_ */ 431