1 /* $NetBSD: uvm_map.c,v 1.136 2003/04/09 21:39:29 thorpej 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.c 8.3 (Berkeley) 1/12/94 42 * from: Id: uvm_map.c,v 1.1.2.27 1998/02/07 01:16:54 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 /* 70 * uvm_map.c: uvm map operations 71 */ 72 73 #include <sys/cdefs.h> 74 __KERNEL_RCSID(0, "$NetBSD: uvm_map.c,v 1.136 2003/04/09 21:39:29 thorpej Exp $"); 75 76 #include "opt_ddb.h" 77 #include "opt_uvmhist.h" 78 #include "opt_sysv.h" 79 80 #include <sys/param.h> 81 #include <sys/systm.h> 82 #include <sys/mman.h> 83 #include <sys/proc.h> 84 #include <sys/malloc.h> 85 #include <sys/pool.h> 86 #include <sys/kernel.h> 87 #include <sys/mount.h> 88 #include <sys/vnode.h> 89 90 #ifdef SYSVSHM 91 #include <sys/shm.h> 92 #endif 93 94 #define UVM_MAP 95 #include <uvm/uvm.h> 96 97 #ifdef DDB 98 #include <uvm/uvm_ddb.h> 99 #endif 100 101 extern struct vm_map *pager_map; 102 103 struct uvm_cnt map_ubackmerge, map_uforwmerge; 104 struct uvm_cnt map_ubimerge, map_unomerge; 105 struct uvm_cnt map_kbackmerge, map_kforwmerge; 106 struct uvm_cnt map_kbimerge, map_knomerge; 107 struct uvm_cnt uvm_map_call, uvm_mlk_call, uvm_mlk_hint; 108 const char vmmapbsy[] = "vmmapbsy"; 109 110 /* 111 * pool for vmspace structures. 112 */ 113 114 struct pool uvm_vmspace_pool; 115 116 /* 117 * pool for dynamically-allocated map entries. 118 */ 119 120 struct pool uvm_map_entry_pool; 121 struct pool uvm_map_entry_kmem_pool; 122 123 MALLOC_DEFINE(M_VMMAP, "VM map", "VM map structures"); 124 MALLOC_DEFINE(M_VMPMAP, "VM pmap", "VM pmap"); 125 126 #ifdef PMAP_GROWKERNEL 127 /* 128 * This global represents the end of the kernel virtual address 129 * space. If we want to exceed this, we must grow the kernel 130 * virtual address space dynamically. 131 * 132 * Note, this variable is locked by kernel_map's lock. 133 */ 134 vaddr_t uvm_maxkaddr; 135 #endif 136 137 /* 138 * macros 139 */ 140 141 /* 142 * uvm_map_entry_link: insert entry into a map 143 * 144 * => map must be locked 145 */ 146 #define uvm_map_entry_link(map, after_where, entry) do { \ 147 (map)->nentries++; \ 148 (entry)->prev = (after_where); \ 149 (entry)->next = (after_where)->next; \ 150 (entry)->prev->next = (entry); \ 151 (entry)->next->prev = (entry); \ 152 } while (/*CONSTCOND*/ 0) 153 154 /* 155 * uvm_map_entry_unlink: remove entry from a map 156 * 157 * => map must be locked 158 */ 159 #define uvm_map_entry_unlink(map, entry) do { \ 160 (map)->nentries--; \ 161 (entry)->next->prev = (entry)->prev; \ 162 (entry)->prev->next = (entry)->next; \ 163 } while (/*CONSTCOND*/ 0) 164 165 /* 166 * SAVE_HINT: saves the specified entry as the hint for future lookups. 167 * 168 * => map need not be locked (protected by hint_lock). 169 */ 170 #define SAVE_HINT(map,check,value) do { \ 171 simple_lock(&(map)->hint_lock); \ 172 if ((map)->hint == (check)) \ 173 (map)->hint = (value); \ 174 simple_unlock(&(map)->hint_lock); \ 175 } while (/*CONSTCOND*/ 0) 176 177 /* 178 * VM_MAP_RANGE_CHECK: check and correct range 179 * 180 * => map must at least be read locked 181 */ 182 183 #define VM_MAP_RANGE_CHECK(map, start, end) do { \ 184 if (start < vm_map_min(map)) \ 185 start = vm_map_min(map); \ 186 if (end > vm_map_max(map)) \ 187 end = vm_map_max(map); \ 188 if (start > end) \ 189 start = end; \ 190 } while (/*CONSTCOND*/ 0) 191 192 /* 193 * local prototypes 194 */ 195 196 static struct vm_map_entry *uvm_mapent_alloc __P((struct vm_map *, int)); 197 static void uvm_mapent_copy __P((struct vm_map_entry *, struct vm_map_entry *)); 198 static void uvm_mapent_free __P((struct vm_map_entry *)); 199 static void uvm_map_entry_unwire __P((struct vm_map *, struct vm_map_entry *)); 200 static void uvm_map_reference_amap __P((struct vm_map_entry *, int)); 201 static void uvm_map_unreference_amap __P((struct vm_map_entry *, int)); 202 203 /* 204 * local inlines 205 */ 206 207 /* 208 * uvm_mapent_alloc: allocate a map entry 209 */ 210 211 static __inline struct vm_map_entry * 212 uvm_mapent_alloc(map, flags) 213 struct vm_map *map; 214 int flags; 215 { 216 struct vm_map_entry *me; 217 int s; 218 int pflags = (flags & UVM_FLAG_NOWAIT) ? PR_NOWAIT : PR_WAITOK; 219 UVMHIST_FUNC("uvm_mapent_alloc"); UVMHIST_CALLED(maphist); 220 221 if (map->flags & VM_MAP_INTRSAFE || cold) { 222 s = splvm(); 223 simple_lock(&uvm.kentry_lock); 224 me = uvm.kentry_free; 225 if (me) uvm.kentry_free = me->next; 226 simple_unlock(&uvm.kentry_lock); 227 splx(s); 228 if (__predict_false(me == NULL)) { 229 panic("uvm_mapent_alloc: out of static map entries, " 230 "check MAX_KMAPENT (currently %d)", 231 MAX_KMAPENT); 232 } 233 me->flags = UVM_MAP_STATIC; 234 } else if (map == kernel_map) { 235 me = pool_get(&uvm_map_entry_kmem_pool, pflags); 236 if (__predict_false(me == NULL)) 237 return NULL; 238 me->flags = UVM_MAP_KMEM; 239 } else { 240 me = pool_get(&uvm_map_entry_pool, pflags); 241 if (__predict_false(me == NULL)) 242 return NULL; 243 me->flags = 0; 244 } 245 246 UVMHIST_LOG(maphist, "<- new entry=0x%x [kentry=%d]", me, 247 ((map->flags & VM_MAP_INTRSAFE) != 0 || map == kernel_map), 0, 0); 248 return(me); 249 } 250 251 /* 252 * uvm_mapent_free: free map entry 253 */ 254 255 static __inline void 256 uvm_mapent_free(me) 257 struct vm_map_entry *me; 258 { 259 int s; 260 UVMHIST_FUNC("uvm_mapent_free"); UVMHIST_CALLED(maphist); 261 262 UVMHIST_LOG(maphist,"<- freeing map entry=0x%x [flags=%d]", 263 me, me->flags, 0, 0); 264 if (me->flags & UVM_MAP_STATIC) { 265 s = splvm(); 266 simple_lock(&uvm.kentry_lock); 267 me->next = uvm.kentry_free; 268 uvm.kentry_free = me; 269 simple_unlock(&uvm.kentry_lock); 270 splx(s); 271 } else if (me->flags & UVM_MAP_KMEM) { 272 pool_put(&uvm_map_entry_kmem_pool, me); 273 } else { 274 pool_put(&uvm_map_entry_pool, me); 275 } 276 } 277 278 /* 279 * uvm_mapent_copy: copy a map entry, preserving flags 280 */ 281 282 static __inline void 283 uvm_mapent_copy(src, dst) 284 struct vm_map_entry *src; 285 struct vm_map_entry *dst; 286 { 287 memcpy(dst, src, ((char *)&src->uvm_map_entry_stop_copy) - 288 ((char *)src)); 289 } 290 291 /* 292 * uvm_map_entry_unwire: unwire a map entry 293 * 294 * => map should be locked by caller 295 */ 296 297 static __inline void 298 uvm_map_entry_unwire(map, entry) 299 struct vm_map *map; 300 struct vm_map_entry *entry; 301 { 302 entry->wired_count = 0; 303 uvm_fault_unwire_locked(map, entry->start, entry->end); 304 } 305 306 307 /* 308 * wrapper for calling amap_ref() 309 */ 310 static __inline void 311 uvm_map_reference_amap(entry, flags) 312 struct vm_map_entry *entry; 313 int flags; 314 { 315 amap_ref(entry->aref.ar_amap, entry->aref.ar_pageoff, 316 (entry->end - entry->start) >> PAGE_SHIFT, flags); 317 } 318 319 320 /* 321 * wrapper for calling amap_unref() 322 */ 323 static __inline void 324 uvm_map_unreference_amap(entry, flags) 325 struct vm_map_entry *entry; 326 int flags; 327 { 328 amap_unref(entry->aref.ar_amap, entry->aref.ar_pageoff, 329 (entry->end - entry->start) >> PAGE_SHIFT, flags); 330 } 331 332 333 /* 334 * uvm_map_init: init mapping system at boot time. note that we allocate 335 * and init the static pool of struct vm_map_entry *'s for the kernel here. 336 */ 337 338 void 339 uvm_map_init() 340 { 341 static struct vm_map_entry kernel_map_entry[MAX_KMAPENT]; 342 #if defined(UVMHIST) 343 static struct uvm_history_ent maphistbuf[100]; 344 static struct uvm_history_ent pdhistbuf[100]; 345 #endif 346 int lcv; 347 348 /* 349 * first, init logging system. 350 */ 351 352 UVMHIST_FUNC("uvm_map_init"); 353 UVMHIST_INIT_STATIC(maphist, maphistbuf); 354 UVMHIST_INIT_STATIC(pdhist, pdhistbuf); 355 UVMHIST_CALLED(maphist); 356 UVMHIST_LOG(maphist,"<starting uvm map system>", 0, 0, 0, 0); 357 UVMCNT_INIT(uvm_map_call, UVMCNT_CNT, 0, 358 "# uvm_map() successful calls", 0); 359 360 UVMCNT_INIT(map_ubackmerge, UVMCNT_CNT, 0, 361 "# uvm_map() back umerges", 0); 362 UVMCNT_INIT(map_uforwmerge, UVMCNT_CNT, 0, 363 "# uvm_map() forward umerges", 0); 364 UVMCNT_INIT(map_ubimerge, UVMCNT_CNT, 0, 365 "# uvm_map() dual umerge", 0); 366 UVMCNT_INIT(map_unomerge, UVMCNT_CNT, 0, 367 "# uvm_map() no umerge", 0); 368 369 UVMCNT_INIT(map_kbackmerge, UVMCNT_CNT, 0, 370 "# uvm_map() back kmerges", 0); 371 UVMCNT_INIT(map_kforwmerge, UVMCNT_CNT, 0, 372 "# uvm_map() forward kmerges", 0); 373 UVMCNT_INIT(map_kbimerge, UVMCNT_CNT, 0, 374 "# uvm_map() dual kmerge", 0); 375 UVMCNT_INIT(map_knomerge, UVMCNT_CNT, 0, 376 "# uvm_map() no kmerge", 0); 377 378 UVMCNT_INIT(uvm_mlk_call, UVMCNT_CNT, 0, "# map lookup calls", 0); 379 UVMCNT_INIT(uvm_mlk_hint, UVMCNT_CNT, 0, "# map lookup hint hits", 0); 380 381 /* 382 * now set up static pool of kernel map entrys ... 383 */ 384 385 simple_lock_init(&uvm.kentry_lock); 386 uvm.kentry_free = NULL; 387 for (lcv = 0 ; lcv < MAX_KMAPENT ; lcv++) { 388 kernel_map_entry[lcv].next = uvm.kentry_free; 389 uvm.kentry_free = &kernel_map_entry[lcv]; 390 } 391 392 /* 393 * initialize the map-related pools. 394 */ 395 pool_init(&uvm_vmspace_pool, sizeof(struct vmspace), 396 0, 0, 0, "vmsppl", &pool_allocator_nointr); 397 pool_init(&uvm_map_entry_pool, sizeof(struct vm_map_entry), 398 0, 0, 0, "vmmpepl", &pool_allocator_nointr); 399 pool_init(&uvm_map_entry_kmem_pool, sizeof(struct vm_map_entry), 400 0, 0, 0, "vmmpekpl", NULL); 401 } 402 403 /* 404 * clippers 405 */ 406 407 /* 408 * uvm_map_clip_start: ensure that the entry begins at or after 409 * the starting address, if it doesn't we split the entry. 410 * 411 * => caller should use UVM_MAP_CLIP_START macro rather than calling 412 * this directly 413 * => map must be locked by caller 414 */ 415 416 void 417 uvm_map_clip_start(map, entry, start) 418 struct vm_map *map; 419 struct vm_map_entry *entry; 420 vaddr_t start; 421 { 422 struct vm_map_entry *new_entry; 423 vaddr_t new_adj; 424 425 /* uvm_map_simplify_entry(map, entry); */ /* XXX */ 426 427 /* 428 * Split off the front portion. note that we must insert the new 429 * entry BEFORE this one, so that this entry has the specified 430 * starting address. 431 */ 432 433 new_entry = uvm_mapent_alloc(map, 0); 434 uvm_mapent_copy(entry, new_entry); /* entry -> new_entry */ 435 436 new_entry->end = start; 437 new_adj = start - new_entry->start; 438 if (entry->object.uvm_obj) 439 entry->offset += new_adj; /* shift start over */ 440 entry->start = start; 441 442 if (new_entry->aref.ar_amap) { 443 amap_splitref(&new_entry->aref, &entry->aref, new_adj); 444 } 445 446 uvm_map_entry_link(map, entry->prev, new_entry); 447 448 if (UVM_ET_ISSUBMAP(entry)) { 449 /* ... unlikely to happen, but play it safe */ 450 uvm_map_reference(new_entry->object.sub_map); 451 } else { 452 if (UVM_ET_ISOBJ(entry) && 453 entry->object.uvm_obj->pgops && 454 entry->object.uvm_obj->pgops->pgo_reference) 455 entry->object.uvm_obj->pgops->pgo_reference( 456 entry->object.uvm_obj); 457 } 458 } 459 460 /* 461 * uvm_map_clip_end: ensure that the entry ends at or before 462 * the ending address, if it does't we split the reference 463 * 464 * => caller should use UVM_MAP_CLIP_END macro rather than calling 465 * this directly 466 * => map must be locked by caller 467 */ 468 469 void 470 uvm_map_clip_end(map, entry, end) 471 struct vm_map *map; 472 struct vm_map_entry *entry; 473 vaddr_t end; 474 { 475 struct vm_map_entry * new_entry; 476 vaddr_t new_adj; /* #bytes we move start forward */ 477 478 /* 479 * Create a new entry and insert it 480 * AFTER the specified entry 481 */ 482 483 new_entry = uvm_mapent_alloc(map, 0); 484 uvm_mapent_copy(entry, new_entry); /* entry -> new_entry */ 485 486 new_entry->start = entry->end = end; 487 new_adj = end - entry->start; 488 if (new_entry->object.uvm_obj) 489 new_entry->offset += new_adj; 490 491 if (entry->aref.ar_amap) 492 amap_splitref(&entry->aref, &new_entry->aref, new_adj); 493 494 uvm_map_entry_link(map, entry, new_entry); 495 496 if (UVM_ET_ISSUBMAP(entry)) { 497 /* ... unlikely to happen, but play it safe */ 498 uvm_map_reference(new_entry->object.sub_map); 499 } else { 500 if (UVM_ET_ISOBJ(entry) && 501 entry->object.uvm_obj->pgops && 502 entry->object.uvm_obj->pgops->pgo_reference) 503 entry->object.uvm_obj->pgops->pgo_reference( 504 entry->object.uvm_obj); 505 } 506 } 507 508 509 /* 510 * M A P - m a i n e n t r y p o i n t 511 */ 512 /* 513 * uvm_map: establish a valid mapping in a map 514 * 515 * => assume startp is page aligned. 516 * => assume size is a multiple of PAGE_SIZE. 517 * => assume sys_mmap provides enough of a "hint" to have us skip 518 * over text/data/bss area. 519 * => map must be unlocked (we will lock it) 520 * => <uobj,uoffset> value meanings (4 cases): 521 * [1] <NULL,uoffset> == uoffset is a hint for PMAP_PREFER 522 * [2] <NULL,UVM_UNKNOWN_OFFSET> == don't PMAP_PREFER 523 * [3] <uobj,uoffset> == normal mapping 524 * [4] <uobj,UVM_UNKNOWN_OFFSET> == uvm_map finds offset based on VA 525 * 526 * case [4] is for kernel mappings where we don't know the offset until 527 * we've found a virtual address. note that kernel object offsets are 528 * always relative to vm_map_min(kernel_map). 529 * 530 * => if `align' is non-zero, we try to align the virtual address to 531 * the specified alignment. this is only a hint; if we can't 532 * do it, the address will be unaligned. this is provided as 533 * a mechanism for large pages. 534 * 535 * => XXXCDC: need way to map in external amap? 536 */ 537 538 int 539 uvm_map(map, startp, size, uobj, uoffset, align, flags) 540 struct vm_map *map; 541 vaddr_t *startp; /* IN/OUT */ 542 vsize_t size; 543 struct uvm_object *uobj; 544 voff_t uoffset; 545 vsize_t align; 546 uvm_flag_t flags; 547 { 548 struct vm_map_entry *prev_entry, *new_entry; 549 const int amapwaitflag = (flags & UVM_FLAG_NOWAIT) ? 550 AMAP_EXTEND_NOWAIT : 0; 551 vm_prot_t prot = UVM_PROTECTION(flags), maxprot = 552 UVM_MAXPROTECTION(flags); 553 vm_inherit_t inherit = UVM_INHERIT(flags); 554 int advice = UVM_ADVICE(flags); 555 int error, merged = 0, kmap = (vm_map_pmap(map) == pmap_kernel()); 556 UVMHIST_FUNC("uvm_map"); 557 UVMHIST_CALLED(maphist); 558 559 UVMHIST_LOG(maphist, "(map=0x%x, *startp=0x%x, size=%d, flags=0x%x)", 560 map, *startp, size, flags); 561 UVMHIST_LOG(maphist, " uobj/offset 0x%x/%d", uobj, uoffset,0,0); 562 563 /* 564 * detect a popular device driver bug. 565 */ 566 567 KASSERT(doing_shutdown || curlwp != NULL || 568 (map->flags & VM_MAP_INTRSAFE)); 569 570 /* 571 * check sanity of protection code 572 */ 573 574 if ((prot & maxprot) != prot) { 575 UVMHIST_LOG(maphist, "<- prot. failure: prot=0x%x, max=0x%x", 576 prot, maxprot,0,0); 577 return EACCES; 578 } 579 580 /* 581 * for pager_map, allocate the new entry first to avoid sleeping 582 * for memory while we have the map locked. 583 */ 584 585 new_entry = NULL; 586 if (map == pager_map) { 587 new_entry = uvm_mapent_alloc(map, (flags & UVM_FLAG_NOWAIT)); 588 if (__predict_false(new_entry == NULL)) 589 return ENOMEM; 590 } 591 592 /* 593 * figure out where to put new VM range 594 */ 595 596 if (vm_map_lock_try(map) == FALSE) { 597 if (flags & UVM_FLAG_TRYLOCK) { 598 if (new_entry) { 599 uvm_mapent_free(new_entry); 600 } 601 return EAGAIN; 602 } 603 vm_map_lock(map); /* could sleep here */ 604 } 605 if ((prev_entry = uvm_map_findspace(map, *startp, size, startp, 606 uobj, uoffset, align, flags)) == NULL) { 607 UVMHIST_LOG(maphist,"<- uvm_map_findspace failed!",0,0,0,0); 608 vm_map_unlock(map); 609 if (new_entry) { 610 uvm_mapent_free(new_entry); 611 } 612 return ENOMEM; 613 } 614 615 #ifdef PMAP_GROWKERNEL 616 { 617 /* 618 * If the kernel pmap can't map the requested space, 619 * then allocate more resources for it. 620 */ 621 if (map == kernel_map && uvm_maxkaddr < (*startp + size)) 622 uvm_maxkaddr = pmap_growkernel(*startp + size); 623 } 624 #endif 625 626 UVMCNT_INCR(uvm_map_call); 627 628 /* 629 * if uobj is null, then uoffset is either a VAC hint for PMAP_PREFER 630 * [typically from uvm_map_reserve] or it is UVM_UNKNOWN_OFFSET. in 631 * either case we want to zero it before storing it in the map entry 632 * (because it looks strange and confusing when debugging...) 633 * 634 * if uobj is not null 635 * if uoffset is not UVM_UNKNOWN_OFFSET then we have a normal mapping 636 * and we do not need to change uoffset. 637 * if uoffset is UVM_UNKNOWN_OFFSET then we need to find the offset 638 * now (based on the starting address of the map). this case is 639 * for kernel object mappings where we don't know the offset until 640 * the virtual address is found (with uvm_map_findspace). the 641 * offset is the distance we are from the start of the map. 642 */ 643 644 if (uobj == NULL) { 645 uoffset = 0; 646 } else { 647 if (uoffset == UVM_UNKNOWN_OFFSET) { 648 KASSERT(UVM_OBJ_IS_KERN_OBJECT(uobj)); 649 uoffset = *startp - vm_map_min(kernel_map); 650 } 651 } 652 653 /* 654 * try and insert in map by extending previous entry, if possible. 655 * XXX: we don't try and pull back the next entry. might be useful 656 * for a stack, but we are currently allocating our stack in advance. 657 */ 658 659 if (flags & UVM_FLAG_NOMERGE) 660 goto nomerge; 661 662 if (prev_entry->end == *startp && 663 prev_entry != &map->header && 664 prev_entry->object.uvm_obj == uobj) { 665 666 if (uobj && prev_entry->offset + 667 (prev_entry->end - prev_entry->start) != uoffset) 668 goto forwardmerge; 669 670 if (UVM_ET_ISSUBMAP(prev_entry)) 671 goto forwardmerge; 672 673 if (prev_entry->protection != prot || 674 prev_entry->max_protection != maxprot) 675 goto forwardmerge; 676 677 if (prev_entry->inheritance != inherit || 678 prev_entry->advice != advice) 679 goto forwardmerge; 680 681 /* wiring status must match (new area is unwired) */ 682 if (VM_MAPENT_ISWIRED(prev_entry)) 683 goto forwardmerge; 684 685 /* 686 * can't extend a shared amap. note: no need to lock amap to 687 * look at refs since we don't care about its exact value. 688 * if it is one (i.e. we have only reference) it will stay there 689 */ 690 691 if (prev_entry->aref.ar_amap && 692 amap_refs(prev_entry->aref.ar_amap) != 1) { 693 goto forwardmerge; 694 } 695 696 if (prev_entry->aref.ar_amap) { 697 error = amap_extend(prev_entry, size, 698 amapwaitflag | AMAP_EXTEND_FORWARDS); 699 if (error) { 700 vm_map_unlock(map); 701 if (new_entry) { 702 uvm_mapent_free(new_entry); 703 } 704 return error; 705 } 706 } 707 708 if (kmap) 709 UVMCNT_INCR(map_kbackmerge); 710 else 711 UVMCNT_INCR(map_ubackmerge); 712 UVMHIST_LOG(maphist," starting back merge", 0, 0, 0, 0); 713 714 /* 715 * drop our reference to uobj since we are extending a reference 716 * that we already have (the ref count can not drop to zero). 717 */ 718 719 if (uobj && uobj->pgops->pgo_detach) 720 uobj->pgops->pgo_detach(uobj); 721 722 prev_entry->end += size; 723 map->size += size; 724 725 UVMHIST_LOG(maphist,"<- done (via backmerge)!", 0, 0, 0, 0); 726 if (new_entry) { 727 uvm_mapent_free(new_entry); 728 new_entry = NULL; 729 } 730 merged++; 731 } 732 733 forwardmerge: 734 if (prev_entry->next->start == (*startp + size) && 735 prev_entry->next != &map->header && 736 prev_entry->next->object.uvm_obj == uobj) { 737 738 if (uobj && prev_entry->next->offset != uoffset + size) 739 goto nomerge; 740 741 if (UVM_ET_ISSUBMAP(prev_entry->next)) 742 goto nomerge; 743 744 if (prev_entry->next->protection != prot || 745 prev_entry->next->max_protection != maxprot) 746 goto nomerge; 747 748 if (prev_entry->next->inheritance != inherit || 749 prev_entry->next->advice != advice) 750 goto nomerge; 751 752 /* wiring status must match (new area is unwired) */ 753 if (VM_MAPENT_ISWIRED(prev_entry->next)) 754 goto nomerge; 755 756 /* 757 * can't extend a shared amap. note: no need to lock amap to 758 * look at refs since we don't care about its exact value. 759 * if it is one (i.e. we have only reference) it will stay there. 760 * 761 * note that we also can't merge two amaps, so if we 762 * merged with the previous entry which has an amap, 763 * and the next entry also has an amap, we give up. 764 * 765 * Interesting cases: 766 * amap, new, amap -> give up second merge (single fwd extend) 767 * amap, new, none -> double forward extend (extend again here) 768 * none, new, amap -> double backward extend (done here) 769 * uobj, new, amap -> single backward extend (done here) 770 * 771 * XXX should we attempt to deal with someone refilling 772 * the deallocated region between two entries that are 773 * backed by the same amap (ie, arefs is 2, "prev" and 774 * "next" refer to it, and adding this allocation will 775 * close the hole, thus restoring arefs to 1 and 776 * deallocating the "next" vm_map_entry)? -- @@@ 777 */ 778 779 if (prev_entry->next->aref.ar_amap && 780 (amap_refs(prev_entry->next->aref.ar_amap) != 1 || 781 (merged && prev_entry->aref.ar_amap))) { 782 goto nomerge; 783 } 784 785 if (merged) { 786 /* 787 * Try to extend the amap of the previous entry to 788 * cover the next entry as well. If it doesn't work 789 * just skip on, don't actually give up, since we've 790 * already completed the back merge. 791 */ 792 if (prev_entry->aref.ar_amap) { 793 if (amap_extend(prev_entry, 794 prev_entry->next->end - 795 prev_entry->next->start, 796 amapwaitflag | AMAP_EXTEND_FORWARDS)) 797 goto nomerge; 798 } 799 800 /* 801 * Try to extend the amap of the *next* entry 802 * back to cover the new allocation *and* the 803 * previous entry as well (the previous merge 804 * didn't have an amap already otherwise we 805 * wouldn't be checking here for an amap). If 806 * it doesn't work just skip on, again, don't 807 * actually give up, since we've already 808 * completed the back merge. 809 */ 810 else if (prev_entry->next->aref.ar_amap) { 811 if (amap_extend(prev_entry->next, 812 prev_entry->end - 813 prev_entry->start + size, 814 amapwaitflag | AMAP_EXTEND_BACKWARDS)) 815 goto nomerge; 816 } 817 } else { 818 /* 819 * Pull the next entry's amap backwards to cover this 820 * new allocation. 821 */ 822 if (prev_entry->next->aref.ar_amap) { 823 error = amap_extend(prev_entry->next, size, 824 amapwaitflag | AMAP_EXTEND_BACKWARDS); 825 if (error) { 826 vm_map_unlock(map); 827 if (new_entry) { 828 uvm_mapent_free(new_entry); 829 } 830 return error; 831 } 832 } 833 } 834 835 if (merged) { 836 if (kmap) { 837 UVMCNT_DECR(map_kbackmerge); 838 UVMCNT_INCR(map_kbimerge); 839 } else { 840 UVMCNT_DECR(map_ubackmerge); 841 UVMCNT_INCR(map_ubimerge); 842 } 843 } else { 844 if (kmap) 845 UVMCNT_INCR(map_kforwmerge); 846 else 847 UVMCNT_INCR(map_uforwmerge); 848 } 849 UVMHIST_LOG(maphist," starting forward merge", 0, 0, 0, 0); 850 851 /* 852 * drop our reference to uobj since we are extending a reference 853 * that we already have (the ref count can not drop to zero). 854 * (if merged, we've already detached) 855 */ 856 if (uobj && uobj->pgops->pgo_detach && !merged) 857 uobj->pgops->pgo_detach(uobj); 858 859 if (merged) { 860 struct vm_map_entry *dead = prev_entry->next; 861 prev_entry->end = dead->end; 862 uvm_map_entry_unlink(map, dead); 863 if (dead->aref.ar_amap != NULL) { 864 prev_entry->aref = dead->aref; 865 dead->aref.ar_amap = NULL; 866 } 867 uvm_mapent_free(dead); 868 } else { 869 prev_entry->next->start -= size; 870 map->size += size; 871 if (uobj) 872 prev_entry->next->offset = uoffset; 873 } 874 875 UVMHIST_LOG(maphist,"<- done forwardmerge", 0, 0, 0, 0); 876 if (new_entry) { 877 uvm_mapent_free(new_entry); 878 new_entry = NULL; 879 } 880 merged++; 881 } 882 883 nomerge: 884 if (!merged) { 885 UVMHIST_LOG(maphist," allocating new map entry", 0, 0, 0, 0); 886 if (kmap) 887 UVMCNT_INCR(map_knomerge); 888 else 889 UVMCNT_INCR(map_unomerge); 890 891 /* 892 * allocate new entry and link it in. 893 */ 894 895 if (new_entry == NULL) { 896 new_entry = uvm_mapent_alloc(map, 897 (flags & UVM_FLAG_NOWAIT)); 898 if (__predict_false(new_entry == NULL)) { 899 vm_map_unlock(map); 900 return ENOMEM; 901 } 902 } 903 new_entry->start = *startp; 904 new_entry->end = new_entry->start + size; 905 new_entry->object.uvm_obj = uobj; 906 new_entry->offset = uoffset; 907 908 if (uobj) 909 new_entry->etype = UVM_ET_OBJ; 910 else 911 new_entry->etype = 0; 912 913 if (flags & UVM_FLAG_COPYONW) { 914 new_entry->etype |= UVM_ET_COPYONWRITE; 915 if ((flags & UVM_FLAG_OVERLAY) == 0) 916 new_entry->etype |= UVM_ET_NEEDSCOPY; 917 } 918 919 new_entry->protection = prot; 920 new_entry->max_protection = maxprot; 921 new_entry->inheritance = inherit; 922 new_entry->wired_count = 0; 923 new_entry->advice = advice; 924 if (flags & UVM_FLAG_OVERLAY) { 925 926 /* 927 * to_add: for BSS we overallocate a little since we 928 * are likely to extend 929 */ 930 931 vaddr_t to_add = (flags & UVM_FLAG_AMAPPAD) ? 932 UVM_AMAP_CHUNK << PAGE_SHIFT : 0; 933 struct vm_amap *amap = amap_alloc(size, to_add, 934 (flags & UVM_FLAG_NOWAIT) ? M_NOWAIT : M_WAITOK); 935 if (__predict_false(amap == NULL)) { 936 vm_map_unlock(map); 937 uvm_mapent_free(new_entry); 938 return ENOMEM; 939 } 940 new_entry->aref.ar_pageoff = 0; 941 new_entry->aref.ar_amap = amap; 942 } else { 943 new_entry->aref.ar_pageoff = 0; 944 new_entry->aref.ar_amap = NULL; 945 } 946 uvm_map_entry_link(map, prev_entry, new_entry); 947 map->size += size; 948 949 /* 950 * Update the free space hint 951 */ 952 953 if ((map->first_free == prev_entry) && 954 (prev_entry->end >= new_entry->start)) 955 map->first_free = new_entry; 956 } 957 958 UVMHIST_LOG(maphist,"<- done!", 0, 0, 0, 0); 959 vm_map_unlock(map); 960 return 0; 961 } 962 963 /* 964 * uvm_map_lookup_entry: find map entry at or before an address 965 * 966 * => map must at least be read-locked by caller 967 * => entry is returned in "entry" 968 * => return value is true if address is in the returned entry 969 */ 970 971 boolean_t 972 uvm_map_lookup_entry(map, address, entry) 973 struct vm_map *map; 974 vaddr_t address; 975 struct vm_map_entry **entry; /* OUT */ 976 { 977 struct vm_map_entry *cur; 978 struct vm_map_entry *last; 979 UVMHIST_FUNC("uvm_map_lookup_entry"); 980 UVMHIST_CALLED(maphist); 981 982 UVMHIST_LOG(maphist,"(map=0x%x,addr=0x%x,ent=0x%x)", 983 map, address, entry, 0); 984 985 /* 986 * start looking either from the head of the 987 * list, or from the hint. 988 */ 989 990 simple_lock(&map->hint_lock); 991 cur = map->hint; 992 simple_unlock(&map->hint_lock); 993 994 if (cur == &map->header) 995 cur = cur->next; 996 997 UVMCNT_INCR(uvm_mlk_call); 998 if (address >= cur->start) { 999 1000 /* 1001 * go from hint to end of list. 1002 * 1003 * but first, make a quick check to see if 1004 * we are already looking at the entry we 1005 * want (which is usually the case). 1006 * note also that we don't need to save the hint 1007 * here... it is the same hint (unless we are 1008 * at the header, in which case the hint didn't 1009 * buy us anything anyway). 1010 */ 1011 1012 last = &map->header; 1013 if ((cur != last) && (cur->end > address)) { 1014 UVMCNT_INCR(uvm_mlk_hint); 1015 *entry = cur; 1016 UVMHIST_LOG(maphist,"<- got it via hint (0x%x)", 1017 cur, 0, 0, 0); 1018 return (TRUE); 1019 } 1020 } else { 1021 1022 /* 1023 * go from start to hint, *inclusively* 1024 */ 1025 1026 last = cur->next; 1027 cur = map->header.next; 1028 } 1029 1030 /* 1031 * search linearly 1032 */ 1033 1034 while (cur != last) { 1035 if (cur->end > address) { 1036 if (address >= cur->start) { 1037 /* 1038 * save this lookup for future 1039 * hints, and return 1040 */ 1041 1042 *entry = cur; 1043 SAVE_HINT(map, map->hint, cur); 1044 UVMHIST_LOG(maphist,"<- search got it (0x%x)", 1045 cur, 0, 0, 0); 1046 return (TRUE); 1047 } 1048 break; 1049 } 1050 cur = cur->next; 1051 } 1052 *entry = cur->prev; 1053 SAVE_HINT(map, map->hint, *entry); 1054 UVMHIST_LOG(maphist,"<- failed!",0,0,0,0); 1055 return (FALSE); 1056 } 1057 1058 /* 1059 * uvm_map_findspace: find "length" sized space in "map". 1060 * 1061 * => "hint" is a hint about where we want it, unless FINDSPACE_FIXED is 1062 * set (in which case we insist on using "hint"). 1063 * => "result" is VA returned 1064 * => uobj/uoffset are to be used to handle VAC alignment, if required 1065 * => if `align' is non-zero, we attempt to align to that value. 1066 * => caller must at least have read-locked map 1067 * => returns NULL on failure, or pointer to prev. map entry if success 1068 * => note this is a cross between the old vm_map_findspace and vm_map_find 1069 */ 1070 1071 struct vm_map_entry * 1072 uvm_map_findspace(map, hint, length, result, uobj, uoffset, align, flags) 1073 struct vm_map *map; 1074 vaddr_t hint; 1075 vsize_t length; 1076 vaddr_t *result; /* OUT */ 1077 struct uvm_object *uobj; 1078 voff_t uoffset; 1079 vsize_t align; 1080 int flags; 1081 { 1082 struct vm_map_entry *entry, *next, *tmp; 1083 vaddr_t end, orig_hint; 1084 const int topdown = map->flags & VM_MAP_TOPDOWN; 1085 UVMHIST_FUNC("uvm_map_findspace"); 1086 UVMHIST_CALLED(maphist); 1087 1088 UVMHIST_LOG(maphist, "(map=0x%x, hint=0x%x, len=%d, flags=0x%x)", 1089 map, hint, length, flags); 1090 KASSERT((align & (align - 1)) == 0); 1091 KASSERT((flags & UVM_FLAG_FIXED) == 0 || align == 0); 1092 1093 /* 1094 * remember the original hint. if we are aligning, then we 1095 * may have to try again with no alignment constraint if 1096 * we fail the first time. 1097 */ 1098 1099 orig_hint = hint; 1100 if (hint < map->min_offset) { /* check ranges ... */ 1101 if (flags & UVM_FLAG_FIXED) { 1102 UVMHIST_LOG(maphist,"<- VA below map range",0,0,0,0); 1103 return(NULL); 1104 } 1105 hint = map->min_offset; 1106 } 1107 if (hint > map->max_offset) { 1108 UVMHIST_LOG(maphist,"<- VA 0x%x > range [0x%x->0x%x]", 1109 hint, map->min_offset, map->max_offset, 0); 1110 return(NULL); 1111 } 1112 1113 /* 1114 * Look for the first possible address; if there's already 1115 * something at this address, we have to start after it. 1116 */ 1117 1118 /* 1119 * @@@: there are four, no, eight cases to consider. 1120 * 1121 * 0: found, fixed, bottom up -> fail 1122 * 1: found, fixed, top down -> fail 1123 * 2: found, not fixed, bottom up -> start after tmp->end, loop up 1124 * 3: found, not fixed, top down -> start before tmp->start, loop down 1125 * 4: not found, fixed, bottom up -> check tmp->next->start, fail 1126 * 5: not found, fixed, top down -> check tmp->next->start, fail 1127 * 6: not found, not fixed, bottom up -> check tmp->next->start, loop up 1128 * 7: not found, not fixed, top down -> check tmp->next->start, loop down 1129 * 1130 * as you can see, it reduces to roughly five cases, and that 1131 * adding top down mapping only adds one unique case (without 1132 * it, there would be four cases). 1133 */ 1134 1135 if ((flags & UVM_FLAG_FIXED) == 0 && hint == map->min_offset) { 1136 if ((entry = map->first_free) != &map->header) 1137 hint = entry->end; 1138 } else { 1139 if (uvm_map_lookup_entry(map, hint, &tmp)) { 1140 /* "hint" address already in use ... */ 1141 if (flags & UVM_FLAG_FIXED) { 1142 UVMHIST_LOG(maphist,"<- fixed & VA in use", 1143 0, 0, 0, 0); 1144 return(NULL); 1145 } 1146 hint = topdown ? tmp->start - length : tmp->end; 1147 } else if ((tmp->next == &map->header || 1148 tmp->next->start >= hint + length)) { 1149 entry = tmp; 1150 goto quickfind; 1151 } 1152 entry = tmp; 1153 } 1154 1155 /* 1156 * Look through the rest of the map, trying to fit a new region in 1157 * the gap between existing regions, or after the very last region. 1158 * note: entry->end = base VA of current gap, 1159 * next->start = VA of end of current gap 1160 */ 1161 1162 for (next = NULL;; hint = topdown ? 1163 (entry = next)->start - length : 1164 (entry = next)->end) { 1165 1166 /* 1167 * Find the end of the proposed new region. Be sure we didn't 1168 * go beyond the end of the map, or wrap around the address; 1169 * if so, we lose. Otherwise, if this is the last entry, or 1170 * if the proposed new region fits before the next entry, we 1171 * win. 1172 */ 1173 1174 #ifdef PMAP_PREFER 1175 /* 1176 * push hint forward as needed to avoid VAC alias problems. 1177 * we only do this if a valid offset is specified. 1178 */ 1179 1180 if ((flags & UVM_FLAG_FIXED) == 0 && 1181 uoffset != UVM_UNKNOWN_OFFSET) 1182 PMAP_PREFER(uoffset, &hint); 1183 #endif 1184 if (align != 0) { 1185 if ((hint & (align - 1)) != 0) { 1186 if (topdown) 1187 hint &= ~(align-1); 1188 else 1189 hint = roundup(hint, align); 1190 } 1191 /* 1192 * XXX Should we PMAP_PREFER() here again? 1193 */ 1194 } 1195 end = hint + length; 1196 if (end > map->max_offset || end < hint) { 1197 UVMHIST_LOG(maphist,"<- failed (off end)", 0,0,0,0); 1198 if (align != 0) { 1199 UVMHIST_LOG(maphist, 1200 "calling recursively, no align", 1201 0,0,0,0); 1202 return (uvm_map_findspace(map, orig_hint, 1203 length, result, uobj, uoffset, 0, flags)); 1204 } 1205 return (NULL); 1206 } 1207 if (!topdown || next == NULL) { 1208 next = entry->next; 1209 } else 1210 next = entry->prev; 1211 if (next == &map->header || 1212 (!topdown && next->start >= end) || 1213 ( topdown && next->end <= hint)) 1214 break; 1215 if (flags & UVM_FLAG_FIXED) { 1216 UVMHIST_LOG(maphist,"<- fixed mapping failed", 0,0,0,0); 1217 return(NULL); /* only one shot at it ... */ 1218 } 1219 } 1220 quickfind: 1221 SAVE_HINT(map, map->hint, entry); 1222 if (topdown && entry->start >= hint + length) 1223 entry = entry->prev; 1224 *result = hint; 1225 UVMHIST_LOG(maphist,"<- got it! (result=0x%x)", hint, 0,0,0); 1226 return (entry); 1227 } 1228 1229 /* 1230 * U N M A P - m a i n h e l p e r f u n c t i o n s 1231 */ 1232 1233 /* 1234 * uvm_unmap_remove: remove mappings from a vm_map (from "start" up to "stop") 1235 * 1236 * => caller must check alignment and size 1237 * => map must be locked by caller 1238 * => we return a list of map entries that we've remove from the map 1239 * in "entry_list" 1240 */ 1241 1242 void 1243 uvm_unmap_remove(map, start, end, entry_list) 1244 struct vm_map *map; 1245 vaddr_t start, end; 1246 struct vm_map_entry **entry_list; /* OUT */ 1247 { 1248 struct vm_map_entry *entry, *first_entry, *next; 1249 vaddr_t len; 1250 UVMHIST_FUNC("uvm_unmap_remove"); UVMHIST_CALLED(maphist); 1251 1252 UVMHIST_LOG(maphist,"(map=0x%x, start=0x%x, end=0x%x)", 1253 map, start, end, 0); 1254 VM_MAP_RANGE_CHECK(map, start, end); 1255 1256 /* 1257 * find first entry 1258 */ 1259 1260 if (uvm_map_lookup_entry(map, start, &first_entry) == TRUE) { 1261 /* clip and go... */ 1262 entry = first_entry; 1263 UVM_MAP_CLIP_START(map, entry, start); 1264 /* critical! prevents stale hint */ 1265 SAVE_HINT(map, entry, entry->prev); 1266 } else { 1267 entry = first_entry->next; 1268 } 1269 1270 /* 1271 * Save the free space hint 1272 */ 1273 1274 if (map->first_free->start >= start) 1275 map->first_free = entry->prev; 1276 1277 /* 1278 * note: we now re-use first_entry for a different task. we remove 1279 * a number of map entries from the map and save them in a linked 1280 * list headed by "first_entry". once we remove them from the map 1281 * the caller should unlock the map and drop the references to the 1282 * backing objects [c.f. uvm_unmap_detach]. the object is to 1283 * separate unmapping from reference dropping. why? 1284 * [1] the map has to be locked for unmapping 1285 * [2] the map need not be locked for reference dropping 1286 * [3] dropping references may trigger pager I/O, and if we hit 1287 * a pager that does synchronous I/O we may have to wait for it. 1288 * [4] we would like all waiting for I/O to occur with maps unlocked 1289 * so that we don't block other threads. 1290 */ 1291 1292 first_entry = NULL; 1293 *entry_list = NULL; 1294 1295 /* 1296 * break up the area into map entry sized regions and unmap. note 1297 * that all mappings have to be removed before we can even consider 1298 * dropping references to amaps or VM objects (otherwise we could end 1299 * up with a mapping to a page on the free list which would be very bad) 1300 */ 1301 1302 while ((entry != &map->header) && (entry->start < end)) { 1303 UVM_MAP_CLIP_END(map, entry, end); 1304 next = entry->next; 1305 len = entry->end - entry->start; 1306 1307 /* 1308 * unwire before removing addresses from the pmap; otherwise 1309 * unwiring will put the entries back into the pmap (XXX). 1310 */ 1311 1312 if (VM_MAPENT_ISWIRED(entry)) { 1313 uvm_map_entry_unwire(map, entry); 1314 } 1315 if ((map->flags & VM_MAP_PAGEABLE) == 0) { 1316 1317 /* 1318 * if the map is non-pageable, any pages mapped there 1319 * must be wired and entered with pmap_kenter_pa(), 1320 * and we should free any such pages immediately. 1321 * this is mostly used for kmem_map and mb_map. 1322 */ 1323 1324 uvm_km_pgremove_intrsafe(entry->start, entry->end); 1325 pmap_kremove(entry->start, len); 1326 } else if (UVM_ET_ISOBJ(entry) && 1327 UVM_OBJ_IS_KERN_OBJECT(entry->object.uvm_obj)) { 1328 KASSERT(vm_map_pmap(map) == pmap_kernel()); 1329 1330 /* 1331 * note: kernel object mappings are currently used in 1332 * two ways: 1333 * [1] "normal" mappings of pages in the kernel object 1334 * [2] uvm_km_valloc'd allocations in which we 1335 * pmap_enter in some non-kernel-object page 1336 * (e.g. vmapbuf). 1337 * 1338 * for case [1], we need to remove the mapping from 1339 * the pmap and then remove the page from the kernel 1340 * object (because, once pages in a kernel object are 1341 * unmapped they are no longer needed, unlike, say, 1342 * a vnode where you might want the data to persist 1343 * until flushed out of a queue). 1344 * 1345 * for case [2], we need to remove the mapping from 1346 * the pmap. there shouldn't be any pages at the 1347 * specified offset in the kernel object [but it 1348 * doesn't hurt to call uvm_km_pgremove just to be 1349 * safe?] 1350 * 1351 * uvm_km_pgremove currently does the following: 1352 * for pages in the kernel object in range: 1353 * - drops the swap slot 1354 * - uvm_pagefree the page 1355 */ 1356 1357 /* 1358 * remove mappings from pmap and drop the pages 1359 * from the object. offsets are always relative 1360 * to vm_map_min(kernel_map). 1361 */ 1362 1363 pmap_remove(pmap_kernel(), entry->start, 1364 entry->start + len); 1365 uvm_km_pgremove(entry->object.uvm_obj, 1366 entry->start - vm_map_min(kernel_map), 1367 entry->end - vm_map_min(kernel_map)); 1368 1369 /* 1370 * null out kernel_object reference, we've just 1371 * dropped it 1372 */ 1373 1374 entry->etype &= ~UVM_ET_OBJ; 1375 entry->object.uvm_obj = NULL; 1376 } else if (UVM_ET_ISOBJ(entry) || entry->aref.ar_amap) { 1377 1378 /* 1379 * remove mappings the standard way. 1380 */ 1381 1382 pmap_remove(map->pmap, entry->start, entry->end); 1383 } 1384 1385 /* 1386 * remove entry from map and put it on our list of entries 1387 * that we've nuked. then go to next entry. 1388 */ 1389 1390 UVMHIST_LOG(maphist, " removed map entry 0x%x", entry, 0, 0,0); 1391 1392 /* critical! prevents stale hint */ 1393 SAVE_HINT(map, entry, entry->prev); 1394 1395 uvm_map_entry_unlink(map, entry); 1396 map->size -= len; 1397 entry->prev = NULL; 1398 entry->next = first_entry; 1399 first_entry = entry; 1400 entry = next; 1401 } 1402 if ((map->flags & VM_MAP_DYING) == 0) { 1403 pmap_update(vm_map_pmap(map)); 1404 } 1405 1406 /* 1407 * now we've cleaned up the map and are ready for the caller to drop 1408 * references to the mapped objects. 1409 */ 1410 1411 *entry_list = first_entry; 1412 UVMHIST_LOG(maphist,"<- done!", 0, 0, 0, 0); 1413 } 1414 1415 /* 1416 * uvm_unmap_detach: drop references in a chain of map entries 1417 * 1418 * => we will free the map entries as we traverse the list. 1419 */ 1420 1421 void 1422 uvm_unmap_detach(first_entry, flags) 1423 struct vm_map_entry *first_entry; 1424 int flags; 1425 { 1426 struct vm_map_entry *next_entry; 1427 UVMHIST_FUNC("uvm_unmap_detach"); UVMHIST_CALLED(maphist); 1428 1429 while (first_entry) { 1430 KASSERT(!VM_MAPENT_ISWIRED(first_entry)); 1431 UVMHIST_LOG(maphist, 1432 " detach 0x%x: amap=0x%x, obj=0x%x, submap?=%d", 1433 first_entry, first_entry->aref.ar_amap, 1434 first_entry->object.uvm_obj, 1435 UVM_ET_ISSUBMAP(first_entry)); 1436 1437 /* 1438 * drop reference to amap, if we've got one 1439 */ 1440 1441 if (first_entry->aref.ar_amap) 1442 uvm_map_unreference_amap(first_entry, flags); 1443 1444 /* 1445 * drop reference to our backing object, if we've got one 1446 */ 1447 1448 KASSERT(!UVM_ET_ISSUBMAP(first_entry)); 1449 if (UVM_ET_ISOBJ(first_entry) && 1450 first_entry->object.uvm_obj->pgops->pgo_detach) { 1451 (*first_entry->object.uvm_obj->pgops->pgo_detach) 1452 (first_entry->object.uvm_obj); 1453 } 1454 next_entry = first_entry->next; 1455 uvm_mapent_free(first_entry); 1456 first_entry = next_entry; 1457 } 1458 UVMHIST_LOG(maphist, "<- done", 0,0,0,0); 1459 } 1460 1461 /* 1462 * E X T R A C T I O N F U N C T I O N S 1463 */ 1464 1465 /* 1466 * uvm_map_reserve: reserve space in a vm_map for future use. 1467 * 1468 * => we reserve space in a map by putting a dummy map entry in the 1469 * map (dummy means obj=NULL, amap=NULL, prot=VM_PROT_NONE) 1470 * => map should be unlocked (we will write lock it) 1471 * => we return true if we were able to reserve space 1472 * => XXXCDC: should be inline? 1473 */ 1474 1475 int 1476 uvm_map_reserve(map, size, offset, align, raddr) 1477 struct vm_map *map; 1478 vsize_t size; 1479 vaddr_t offset; /* hint for pmap_prefer */ 1480 vsize_t align; /* alignment hint */ 1481 vaddr_t *raddr; /* IN:hint, OUT: reserved VA */ 1482 { 1483 UVMHIST_FUNC("uvm_map_reserve"); UVMHIST_CALLED(maphist); 1484 1485 UVMHIST_LOG(maphist, "(map=0x%x, size=0x%x, offset=0x%x,addr=0x%x)", 1486 map,size,offset,raddr); 1487 1488 size = round_page(size); 1489 if (*raddr < vm_map_min(map)) 1490 *raddr = vm_map_min(map); /* hint */ 1491 1492 /* 1493 * reserve some virtual space. 1494 */ 1495 1496 if (uvm_map(map, raddr, size, NULL, offset, 0, 1497 UVM_MAPFLAG(UVM_PROT_NONE, UVM_PROT_NONE, UVM_INH_NONE, 1498 UVM_ADV_RANDOM, UVM_FLAG_NOMERGE)) != 0) { 1499 UVMHIST_LOG(maphist, "<- done (no VM)", 0,0,0,0); 1500 return (FALSE); 1501 } 1502 1503 UVMHIST_LOG(maphist, "<- done (*raddr=0x%x)", *raddr,0,0,0); 1504 return (TRUE); 1505 } 1506 1507 /* 1508 * uvm_map_replace: replace a reserved (blank) area of memory with 1509 * real mappings. 1510 * 1511 * => caller must WRITE-LOCK the map 1512 * => we return TRUE if replacement was a success 1513 * => we expect the newents chain to have nnewents entrys on it and 1514 * we expect newents->prev to point to the last entry on the list 1515 * => note newents is allowed to be NULL 1516 */ 1517 1518 int 1519 uvm_map_replace(map, start, end, newents, nnewents) 1520 struct vm_map *map; 1521 vaddr_t start, end; 1522 struct vm_map_entry *newents; 1523 int nnewents; 1524 { 1525 struct vm_map_entry *oldent, *last; 1526 1527 /* 1528 * first find the blank map entry at the specified address 1529 */ 1530 1531 if (!uvm_map_lookup_entry(map, start, &oldent)) { 1532 return(FALSE); 1533 } 1534 1535 /* 1536 * check to make sure we have a proper blank entry 1537 */ 1538 1539 if (oldent->start != start || oldent->end != end || 1540 oldent->object.uvm_obj != NULL || oldent->aref.ar_amap != NULL) { 1541 return (FALSE); 1542 } 1543 1544 #ifdef DIAGNOSTIC 1545 1546 /* 1547 * sanity check the newents chain 1548 */ 1549 1550 { 1551 struct vm_map_entry *tmpent = newents; 1552 int nent = 0; 1553 vaddr_t cur = start; 1554 1555 while (tmpent) { 1556 nent++; 1557 if (tmpent->start < cur) 1558 panic("uvm_map_replace1"); 1559 if (tmpent->start > tmpent->end || tmpent->end > end) { 1560 printf("tmpent->start=0x%lx, tmpent->end=0x%lx, end=0x%lx\n", 1561 tmpent->start, tmpent->end, end); 1562 panic("uvm_map_replace2"); 1563 } 1564 cur = tmpent->end; 1565 if (tmpent->next) { 1566 if (tmpent->next->prev != tmpent) 1567 panic("uvm_map_replace3"); 1568 } else { 1569 if (newents->prev != tmpent) 1570 panic("uvm_map_replace4"); 1571 } 1572 tmpent = tmpent->next; 1573 } 1574 if (nent != nnewents) 1575 panic("uvm_map_replace5"); 1576 } 1577 #endif 1578 1579 /* 1580 * map entry is a valid blank! replace it. (this does all the 1581 * work of map entry link/unlink...). 1582 */ 1583 1584 if (newents) { 1585 last = newents->prev; 1586 1587 /* critical: flush stale hints out of map */ 1588 SAVE_HINT(map, map->hint, newents); 1589 if (map->first_free == oldent) 1590 map->first_free = last; 1591 1592 last->next = oldent->next; 1593 last->next->prev = last; 1594 newents->prev = oldent->prev; 1595 newents->prev->next = newents; 1596 map->nentries = map->nentries + (nnewents - 1); 1597 1598 } else { 1599 1600 /* critical: flush stale hints out of map */ 1601 SAVE_HINT(map, map->hint, oldent->prev); 1602 if (map->first_free == oldent) 1603 map->first_free = oldent->prev; 1604 1605 /* NULL list of new entries: just remove the old one */ 1606 uvm_map_entry_unlink(map, oldent); 1607 } 1608 1609 1610 /* 1611 * now we can free the old blank entry, unlock the map and return. 1612 */ 1613 1614 uvm_mapent_free(oldent); 1615 return(TRUE); 1616 } 1617 1618 /* 1619 * uvm_map_extract: extract a mapping from a map and put it somewhere 1620 * (maybe removing the old mapping) 1621 * 1622 * => maps should be unlocked (we will write lock them) 1623 * => returns 0 on success, error code otherwise 1624 * => start must be page aligned 1625 * => len must be page sized 1626 * => flags: 1627 * UVM_EXTRACT_REMOVE: remove mappings from srcmap 1628 * UVM_EXTRACT_CONTIG: abort if unmapped area (advisory only) 1629 * UVM_EXTRACT_QREF: for a temporary extraction do quick obj refs 1630 * UVM_EXTRACT_FIXPROT: set prot to maxprot as we go 1631 * >>>NOTE: if you set REMOVE, you are not allowed to use CONTIG or QREF!<<< 1632 * >>>NOTE: QREF's must be unmapped via the QREF path, thus should only 1633 * be used from within the kernel in a kernel level map <<< 1634 */ 1635 1636 int 1637 uvm_map_extract(srcmap, start, len, dstmap, dstaddrp, flags) 1638 struct vm_map *srcmap, *dstmap; 1639 vaddr_t start, *dstaddrp; 1640 vsize_t len; 1641 int flags; 1642 { 1643 vaddr_t dstaddr, end, newend, oldoffset, fudge, orig_fudge, 1644 oldstart; 1645 struct vm_map_entry *chain, *endchain, *entry, *orig_entry, *newentry, 1646 *deadentry, *oldentry; 1647 vsize_t elen; 1648 int nchain, error, copy_ok; 1649 UVMHIST_FUNC("uvm_map_extract"); UVMHIST_CALLED(maphist); 1650 1651 UVMHIST_LOG(maphist,"(srcmap=0x%x,start=0x%x, len=0x%x", srcmap, start, 1652 len,0); 1653 UVMHIST_LOG(maphist," ...,dstmap=0x%x, flags=0x%x)", dstmap,flags,0,0); 1654 1655 /* 1656 * step 0: sanity check: start must be on a page boundary, length 1657 * must be page sized. can't ask for CONTIG/QREF if you asked for 1658 * REMOVE. 1659 */ 1660 1661 KASSERT((start & PAGE_MASK) == 0 && (len & PAGE_MASK) == 0); 1662 KASSERT((flags & UVM_EXTRACT_REMOVE) == 0 || 1663 (flags & (UVM_EXTRACT_CONTIG|UVM_EXTRACT_QREF)) == 0); 1664 1665 /* 1666 * step 1: reserve space in the target map for the extracted area 1667 */ 1668 1669 dstaddr = vm_map_min(dstmap); 1670 if (uvm_map_reserve(dstmap, len, start, 0, &dstaddr) == FALSE) 1671 return(ENOMEM); 1672 *dstaddrp = dstaddr; /* pass address back to caller */ 1673 UVMHIST_LOG(maphist, " dstaddr=0x%x", dstaddr,0,0,0); 1674 1675 /* 1676 * step 2: setup for the extraction process loop by init'ing the 1677 * map entry chain, locking src map, and looking up the first useful 1678 * entry in the map. 1679 */ 1680 1681 end = start + len; 1682 newend = dstaddr + len; 1683 chain = endchain = NULL; 1684 nchain = 0; 1685 vm_map_lock(srcmap); 1686 1687 if (uvm_map_lookup_entry(srcmap, start, &entry)) { 1688 1689 /* "start" is within an entry */ 1690 if (flags & UVM_EXTRACT_QREF) { 1691 1692 /* 1693 * for quick references we don't clip the entry, so 1694 * the entry may map space "before" the starting 1695 * virtual address... this is the "fudge" factor 1696 * (which can be non-zero only the first time 1697 * through the "while" loop in step 3). 1698 */ 1699 1700 fudge = start - entry->start; 1701 } else { 1702 1703 /* 1704 * normal reference: we clip the map to fit (thus 1705 * fudge is zero) 1706 */ 1707 1708 UVM_MAP_CLIP_START(srcmap, entry, start); 1709 SAVE_HINT(srcmap, srcmap->hint, entry->prev); 1710 fudge = 0; 1711 } 1712 } else { 1713 1714 /* "start" is not within an entry ... skip to next entry */ 1715 if (flags & UVM_EXTRACT_CONTIG) { 1716 error = EINVAL; 1717 goto bad; /* definite hole here ... */ 1718 } 1719 1720 entry = entry->next; 1721 fudge = 0; 1722 } 1723 1724 /* save values from srcmap for step 6 */ 1725 orig_entry = entry; 1726 orig_fudge = fudge; 1727 1728 /* 1729 * step 3: now start looping through the map entries, extracting 1730 * as we go. 1731 */ 1732 1733 while (entry->start < end && entry != &srcmap->header) { 1734 1735 /* if we are not doing a quick reference, clip it */ 1736 if ((flags & UVM_EXTRACT_QREF) == 0) 1737 UVM_MAP_CLIP_END(srcmap, entry, end); 1738 1739 /* clear needs_copy (allow chunking) */ 1740 if (UVM_ET_ISNEEDSCOPY(entry)) { 1741 if (fudge) 1742 oldstart = entry->start; 1743 else 1744 oldstart = 0; /* XXX: gcc */ 1745 amap_copy(srcmap, entry, M_NOWAIT, TRUE, start, end); 1746 if (UVM_ET_ISNEEDSCOPY(entry)) { /* failed? */ 1747 error = ENOMEM; 1748 goto bad; 1749 } 1750 1751 /* amap_copy could clip (during chunk)! update fudge */ 1752 if (fudge) { 1753 fudge = fudge - (entry->start - oldstart); 1754 orig_fudge = fudge; 1755 } 1756 } 1757 1758 /* calculate the offset of this from "start" */ 1759 oldoffset = (entry->start + fudge) - start; 1760 1761 /* allocate a new map entry */ 1762 newentry = uvm_mapent_alloc(dstmap, 0); 1763 if (newentry == NULL) { 1764 error = ENOMEM; 1765 goto bad; 1766 } 1767 1768 /* set up new map entry */ 1769 newentry->next = NULL; 1770 newentry->prev = endchain; 1771 newentry->start = dstaddr + oldoffset; 1772 newentry->end = 1773 newentry->start + (entry->end - (entry->start + fudge)); 1774 if (newentry->end > newend || newentry->end < newentry->start) 1775 newentry->end = newend; 1776 newentry->object.uvm_obj = entry->object.uvm_obj; 1777 if (newentry->object.uvm_obj) { 1778 if (newentry->object.uvm_obj->pgops->pgo_reference) 1779 newentry->object.uvm_obj->pgops-> 1780 pgo_reference(newentry->object.uvm_obj); 1781 newentry->offset = entry->offset + fudge; 1782 } else { 1783 newentry->offset = 0; 1784 } 1785 newentry->etype = entry->etype; 1786 newentry->protection = (flags & UVM_EXTRACT_FIXPROT) ? 1787 entry->max_protection : entry->protection; 1788 newentry->max_protection = entry->max_protection; 1789 newentry->inheritance = entry->inheritance; 1790 newentry->wired_count = 0; 1791 newentry->aref.ar_amap = entry->aref.ar_amap; 1792 if (newentry->aref.ar_amap) { 1793 newentry->aref.ar_pageoff = 1794 entry->aref.ar_pageoff + (fudge >> PAGE_SHIFT); 1795 uvm_map_reference_amap(newentry, AMAP_SHARED | 1796 ((flags & UVM_EXTRACT_QREF) ? AMAP_REFALL : 0)); 1797 } else { 1798 newentry->aref.ar_pageoff = 0; 1799 } 1800 newentry->advice = entry->advice; 1801 1802 /* now link it on the chain */ 1803 nchain++; 1804 if (endchain == NULL) { 1805 chain = endchain = newentry; 1806 } else { 1807 endchain->next = newentry; 1808 endchain = newentry; 1809 } 1810 1811 /* end of 'while' loop! */ 1812 if ((flags & UVM_EXTRACT_CONTIG) && entry->end < end && 1813 (entry->next == &srcmap->header || 1814 entry->next->start != entry->end)) { 1815 error = EINVAL; 1816 goto bad; 1817 } 1818 entry = entry->next; 1819 fudge = 0; 1820 } 1821 1822 /* 1823 * step 4: close off chain (in format expected by uvm_map_replace) 1824 */ 1825 1826 if (chain) 1827 chain->prev = endchain; 1828 1829 /* 1830 * step 5: attempt to lock the dest map so we can pmap_copy. 1831 * note usage of copy_ok: 1832 * 1 => dstmap locked, pmap_copy ok, and we "replace" here (step 5) 1833 * 0 => dstmap unlocked, NO pmap_copy, and we will "replace" in step 7 1834 */ 1835 1836 if (srcmap == dstmap || vm_map_lock_try(dstmap) == TRUE) { 1837 copy_ok = 1; 1838 if (!uvm_map_replace(dstmap, dstaddr, dstaddr+len, chain, 1839 nchain)) { 1840 if (srcmap != dstmap) 1841 vm_map_unlock(dstmap); 1842 error = EIO; 1843 goto bad; 1844 } 1845 } else { 1846 copy_ok = 0; 1847 /* replace defered until step 7 */ 1848 } 1849 1850 /* 1851 * step 6: traverse the srcmap a second time to do the following: 1852 * - if we got a lock on the dstmap do pmap_copy 1853 * - if UVM_EXTRACT_REMOVE remove the entries 1854 * we make use of orig_entry and orig_fudge (saved in step 2) 1855 */ 1856 1857 if (copy_ok || (flags & UVM_EXTRACT_REMOVE)) { 1858 1859 /* purge possible stale hints from srcmap */ 1860 if (flags & UVM_EXTRACT_REMOVE) { 1861 SAVE_HINT(srcmap, srcmap->hint, orig_entry->prev); 1862 if (srcmap->first_free->start >= start) 1863 srcmap->first_free = orig_entry->prev; 1864 } 1865 1866 entry = orig_entry; 1867 fudge = orig_fudge; 1868 deadentry = NULL; /* for UVM_EXTRACT_REMOVE */ 1869 1870 while (entry->start < end && entry != &srcmap->header) { 1871 if (copy_ok) { 1872 oldoffset = (entry->start + fudge) - start; 1873 elen = MIN(end, entry->end) - 1874 (entry->start + fudge); 1875 pmap_copy(dstmap->pmap, srcmap->pmap, 1876 dstaddr + oldoffset, elen, 1877 entry->start + fudge); 1878 } 1879 1880 /* we advance "entry" in the following if statement */ 1881 if (flags & UVM_EXTRACT_REMOVE) { 1882 pmap_remove(srcmap->pmap, entry->start, 1883 entry->end); 1884 oldentry = entry; /* save entry */ 1885 entry = entry->next; /* advance */ 1886 uvm_map_entry_unlink(srcmap, oldentry); 1887 /* add to dead list */ 1888 oldentry->next = deadentry; 1889 deadentry = oldentry; 1890 } else { 1891 entry = entry->next; /* advance */ 1892 } 1893 1894 /* end of 'while' loop */ 1895 fudge = 0; 1896 } 1897 pmap_update(srcmap->pmap); 1898 1899 /* 1900 * unlock dstmap. we will dispose of deadentry in 1901 * step 7 if needed 1902 */ 1903 1904 if (copy_ok && srcmap != dstmap) 1905 vm_map_unlock(dstmap); 1906 1907 } else { 1908 deadentry = NULL; 1909 } 1910 1911 /* 1912 * step 7: we are done with the source map, unlock. if copy_ok 1913 * is 0 then we have not replaced the dummy mapping in dstmap yet 1914 * and we need to do so now. 1915 */ 1916 1917 vm_map_unlock(srcmap); 1918 if ((flags & UVM_EXTRACT_REMOVE) && deadentry) 1919 uvm_unmap_detach(deadentry, 0); /* dispose of old entries */ 1920 1921 /* now do the replacement if we didn't do it in step 5 */ 1922 if (copy_ok == 0) { 1923 vm_map_lock(dstmap); 1924 error = uvm_map_replace(dstmap, dstaddr, dstaddr+len, chain, 1925 nchain); 1926 vm_map_unlock(dstmap); 1927 1928 if (error == FALSE) { 1929 error = EIO; 1930 goto bad2; 1931 } 1932 } 1933 return(0); 1934 1935 /* 1936 * bad: failure recovery 1937 */ 1938 bad: 1939 vm_map_unlock(srcmap); 1940 bad2: /* src already unlocked */ 1941 if (chain) 1942 uvm_unmap_detach(chain, 1943 (flags & UVM_EXTRACT_QREF) ? AMAP_REFALL : 0); 1944 uvm_unmap(dstmap, dstaddr, dstaddr+len); /* ??? */ 1945 return(error); 1946 } 1947 1948 /* end of extraction functions */ 1949 1950 /* 1951 * uvm_map_submap: punch down part of a map into a submap 1952 * 1953 * => only the kernel_map is allowed to be submapped 1954 * => the purpose of submapping is to break up the locking granularity 1955 * of a larger map 1956 * => the range specified must have been mapped previously with a uvm_map() 1957 * call [with uobj==NULL] to create a blank map entry in the main map. 1958 * [And it had better still be blank!] 1959 * => maps which contain submaps should never be copied or forked. 1960 * => to remove a submap, use uvm_unmap() on the main map 1961 * and then uvm_map_deallocate() the submap. 1962 * => main map must be unlocked. 1963 * => submap must have been init'd and have a zero reference count. 1964 * [need not be locked as we don't actually reference it] 1965 */ 1966 1967 int 1968 uvm_map_submap(map, start, end, submap) 1969 struct vm_map *map, *submap; 1970 vaddr_t start, end; 1971 { 1972 struct vm_map_entry *entry; 1973 int error; 1974 1975 vm_map_lock(map); 1976 VM_MAP_RANGE_CHECK(map, start, end); 1977 1978 if (uvm_map_lookup_entry(map, start, &entry)) { 1979 UVM_MAP_CLIP_START(map, entry, start); 1980 UVM_MAP_CLIP_END(map, entry, end); /* to be safe */ 1981 } else { 1982 entry = NULL; 1983 } 1984 1985 if (entry != NULL && 1986 entry->start == start && entry->end == end && 1987 entry->object.uvm_obj == NULL && entry->aref.ar_amap == NULL && 1988 !UVM_ET_ISCOPYONWRITE(entry) && !UVM_ET_ISNEEDSCOPY(entry)) { 1989 entry->etype |= UVM_ET_SUBMAP; 1990 entry->object.sub_map = submap; 1991 entry->offset = 0; 1992 uvm_map_reference(submap); 1993 error = 0; 1994 } else { 1995 error = EINVAL; 1996 } 1997 vm_map_unlock(map); 1998 return error; 1999 } 2000 2001 2002 /* 2003 * uvm_map_protect: change map protection 2004 * 2005 * => set_max means set max_protection. 2006 * => map must be unlocked. 2007 */ 2008 2009 #define MASK(entry) (UVM_ET_ISCOPYONWRITE(entry) ? \ 2010 ~VM_PROT_WRITE : VM_PROT_ALL) 2011 2012 int 2013 uvm_map_protect(map, start, end, new_prot, set_max) 2014 struct vm_map *map; 2015 vaddr_t start, end; 2016 vm_prot_t new_prot; 2017 boolean_t set_max; 2018 { 2019 struct vm_map_entry *current, *entry; 2020 int error = 0; 2021 UVMHIST_FUNC("uvm_map_protect"); UVMHIST_CALLED(maphist); 2022 UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,new_prot=0x%x)", 2023 map, start, end, new_prot); 2024 2025 vm_map_lock(map); 2026 VM_MAP_RANGE_CHECK(map, start, end); 2027 if (uvm_map_lookup_entry(map, start, &entry)) { 2028 UVM_MAP_CLIP_START(map, entry, start); 2029 } else { 2030 entry = entry->next; 2031 } 2032 2033 /* 2034 * make a first pass to check for protection violations. 2035 */ 2036 2037 current = entry; 2038 while ((current != &map->header) && (current->start < end)) { 2039 if (UVM_ET_ISSUBMAP(current)) { 2040 error = EINVAL; 2041 goto out; 2042 } 2043 if ((new_prot & current->max_protection) != new_prot) { 2044 error = EACCES; 2045 goto out; 2046 } 2047 /* 2048 * Don't allow VM_PROT_EXECUTE to be set on entries that 2049 * point to vnodes that are associated with a NOEXEC file 2050 * system. 2051 */ 2052 if (UVM_ET_ISOBJ(current) && 2053 UVM_OBJ_IS_VNODE(current->object.uvm_obj)) { 2054 struct vnode *vp = 2055 (struct vnode *) current->object.uvm_obj; 2056 2057 if ((new_prot & VM_PROT_EXECUTE) != 0 && 2058 (vp->v_mount->mnt_flag & MNT_NOEXEC) != 0) { 2059 error = EACCES; 2060 goto out; 2061 } 2062 } 2063 current = current->next; 2064 } 2065 2066 /* go back and fix up protections (no need to clip this time). */ 2067 2068 current = entry; 2069 while ((current != &map->header) && (current->start < end)) { 2070 vm_prot_t old_prot; 2071 2072 UVM_MAP_CLIP_END(map, current, end); 2073 old_prot = current->protection; 2074 if (set_max) 2075 current->protection = 2076 (current->max_protection = new_prot) & old_prot; 2077 else 2078 current->protection = new_prot; 2079 2080 /* 2081 * update physical map if necessary. worry about copy-on-write 2082 * here -- CHECK THIS XXX 2083 */ 2084 2085 if (current->protection != old_prot) { 2086 /* update pmap! */ 2087 pmap_protect(map->pmap, current->start, current->end, 2088 current->protection & MASK(entry)); 2089 2090 /* 2091 * If this entry points at a vnode, and the 2092 * protection includes VM_PROT_EXECUTE, mark 2093 * the vnode as VEXECMAP. 2094 */ 2095 if (UVM_ET_ISOBJ(current)) { 2096 struct uvm_object *uobj = 2097 current->object.uvm_obj; 2098 2099 if (UVM_OBJ_IS_VNODE(uobj) && 2100 (current->protection & VM_PROT_EXECUTE)) 2101 vn_markexec((struct vnode *) uobj); 2102 } 2103 } 2104 2105 /* 2106 * If the map is configured to lock any future mappings, 2107 * wire this entry now if the old protection was VM_PROT_NONE 2108 * and the new protection is not VM_PROT_NONE. 2109 */ 2110 2111 if ((map->flags & VM_MAP_WIREFUTURE) != 0 && 2112 VM_MAPENT_ISWIRED(entry) == 0 && 2113 old_prot == VM_PROT_NONE && 2114 new_prot != VM_PROT_NONE) { 2115 if (uvm_map_pageable(map, entry->start, 2116 entry->end, FALSE, 2117 UVM_LK_ENTER|UVM_LK_EXIT) != 0) { 2118 2119 /* 2120 * If locking the entry fails, remember the 2121 * error if it's the first one. Note we 2122 * still continue setting the protection in 2123 * the map, but will return the error 2124 * condition regardless. 2125 * 2126 * XXX Ignore what the actual error is, 2127 * XXX just call it a resource shortage 2128 * XXX so that it doesn't get confused 2129 * XXX what uvm_map_protect() itself would 2130 * XXX normally return. 2131 */ 2132 2133 error = ENOMEM; 2134 } 2135 } 2136 current = current->next; 2137 } 2138 pmap_update(map->pmap); 2139 2140 out: 2141 vm_map_unlock(map); 2142 UVMHIST_LOG(maphist, "<- done, error=%d",error,0,0,0); 2143 return error; 2144 } 2145 2146 #undef MASK 2147 2148 /* 2149 * uvm_map_inherit: set inheritance code for range of addrs in map. 2150 * 2151 * => map must be unlocked 2152 * => note that the inherit code is used during a "fork". see fork 2153 * code for details. 2154 */ 2155 2156 int 2157 uvm_map_inherit(map, start, end, new_inheritance) 2158 struct vm_map *map; 2159 vaddr_t start; 2160 vaddr_t end; 2161 vm_inherit_t new_inheritance; 2162 { 2163 struct vm_map_entry *entry, *temp_entry; 2164 UVMHIST_FUNC("uvm_map_inherit"); UVMHIST_CALLED(maphist); 2165 UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,new_inh=0x%x)", 2166 map, start, end, new_inheritance); 2167 2168 switch (new_inheritance) { 2169 case MAP_INHERIT_NONE: 2170 case MAP_INHERIT_COPY: 2171 case MAP_INHERIT_SHARE: 2172 break; 2173 default: 2174 UVMHIST_LOG(maphist,"<- done (INVALID ARG)",0,0,0,0); 2175 return EINVAL; 2176 } 2177 2178 vm_map_lock(map); 2179 VM_MAP_RANGE_CHECK(map, start, end); 2180 if (uvm_map_lookup_entry(map, start, &temp_entry)) { 2181 entry = temp_entry; 2182 UVM_MAP_CLIP_START(map, entry, start); 2183 } else { 2184 entry = temp_entry->next; 2185 } 2186 while ((entry != &map->header) && (entry->start < end)) { 2187 UVM_MAP_CLIP_END(map, entry, end); 2188 entry->inheritance = new_inheritance; 2189 entry = entry->next; 2190 } 2191 vm_map_unlock(map); 2192 UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0); 2193 return 0; 2194 } 2195 2196 /* 2197 * uvm_map_advice: set advice code for range of addrs in map. 2198 * 2199 * => map must be unlocked 2200 */ 2201 2202 int 2203 uvm_map_advice(map, start, end, new_advice) 2204 struct vm_map *map; 2205 vaddr_t start; 2206 vaddr_t end; 2207 int new_advice; 2208 { 2209 struct vm_map_entry *entry, *temp_entry; 2210 UVMHIST_FUNC("uvm_map_advice"); UVMHIST_CALLED(maphist); 2211 UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,new_adv=0x%x)", 2212 map, start, end, new_advice); 2213 2214 vm_map_lock(map); 2215 VM_MAP_RANGE_CHECK(map, start, end); 2216 if (uvm_map_lookup_entry(map, start, &temp_entry)) { 2217 entry = temp_entry; 2218 UVM_MAP_CLIP_START(map, entry, start); 2219 } else { 2220 entry = temp_entry->next; 2221 } 2222 2223 /* 2224 * XXXJRT: disallow holes? 2225 */ 2226 2227 while ((entry != &map->header) && (entry->start < end)) { 2228 UVM_MAP_CLIP_END(map, entry, end); 2229 2230 switch (new_advice) { 2231 case MADV_NORMAL: 2232 case MADV_RANDOM: 2233 case MADV_SEQUENTIAL: 2234 /* nothing special here */ 2235 break; 2236 2237 default: 2238 vm_map_unlock(map); 2239 UVMHIST_LOG(maphist,"<- done (INVALID ARG)",0,0,0,0); 2240 return EINVAL; 2241 } 2242 entry->advice = new_advice; 2243 entry = entry->next; 2244 } 2245 2246 vm_map_unlock(map); 2247 UVMHIST_LOG(maphist,"<- done (OK)",0,0,0,0); 2248 return 0; 2249 } 2250 2251 /* 2252 * uvm_map_pageable: sets the pageability of a range in a map. 2253 * 2254 * => wires map entries. should not be used for transient page locking. 2255 * for that, use uvm_fault_wire()/uvm_fault_unwire() (see uvm_vslock()). 2256 * => regions sepcified as not pageable require lock-down (wired) memory 2257 * and page tables. 2258 * => map must never be read-locked 2259 * => if islocked is TRUE, map is already write-locked 2260 * => we always unlock the map, since we must downgrade to a read-lock 2261 * to call uvm_fault_wire() 2262 * => XXXCDC: check this and try and clean it up. 2263 */ 2264 2265 int 2266 uvm_map_pageable(map, start, end, new_pageable, lockflags) 2267 struct vm_map *map; 2268 vaddr_t start, end; 2269 boolean_t new_pageable; 2270 int lockflags; 2271 { 2272 struct vm_map_entry *entry, *start_entry, *failed_entry; 2273 int rv; 2274 #ifdef DIAGNOSTIC 2275 u_int timestamp_save; 2276 #endif 2277 UVMHIST_FUNC("uvm_map_pageable"); UVMHIST_CALLED(maphist); 2278 UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,new_pageable=0x%x)", 2279 map, start, end, new_pageable); 2280 KASSERT(map->flags & VM_MAP_PAGEABLE); 2281 2282 if ((lockflags & UVM_LK_ENTER) == 0) 2283 vm_map_lock(map); 2284 VM_MAP_RANGE_CHECK(map, start, end); 2285 2286 /* 2287 * only one pageability change may take place at one time, since 2288 * uvm_fault_wire assumes it will be called only once for each 2289 * wiring/unwiring. therefore, we have to make sure we're actually 2290 * changing the pageability for the entire region. we do so before 2291 * making any changes. 2292 */ 2293 2294 if (uvm_map_lookup_entry(map, start, &start_entry) == FALSE) { 2295 if ((lockflags & UVM_LK_EXIT) == 0) 2296 vm_map_unlock(map); 2297 2298 UVMHIST_LOG(maphist,"<- done (fault)",0,0,0,0); 2299 return EFAULT; 2300 } 2301 entry = start_entry; 2302 2303 /* 2304 * handle wiring and unwiring separately. 2305 */ 2306 2307 if (new_pageable) { /* unwire */ 2308 UVM_MAP_CLIP_START(map, entry, start); 2309 2310 /* 2311 * unwiring. first ensure that the range to be unwired is 2312 * really wired down and that there are no holes. 2313 */ 2314 2315 while ((entry != &map->header) && (entry->start < end)) { 2316 if (entry->wired_count == 0 || 2317 (entry->end < end && 2318 (entry->next == &map->header || 2319 entry->next->start > entry->end))) { 2320 if ((lockflags & UVM_LK_EXIT) == 0) 2321 vm_map_unlock(map); 2322 UVMHIST_LOG(maphist, "<- done (INVAL)",0,0,0,0); 2323 return EINVAL; 2324 } 2325 entry = entry->next; 2326 } 2327 2328 /* 2329 * POSIX 1003.1b - a single munlock call unlocks a region, 2330 * regardless of the number of mlock calls made on that 2331 * region. 2332 */ 2333 2334 entry = start_entry; 2335 while ((entry != &map->header) && (entry->start < end)) { 2336 UVM_MAP_CLIP_END(map, entry, end); 2337 if (VM_MAPENT_ISWIRED(entry)) 2338 uvm_map_entry_unwire(map, entry); 2339 entry = entry->next; 2340 } 2341 if ((lockflags & UVM_LK_EXIT) == 0) 2342 vm_map_unlock(map); 2343 UVMHIST_LOG(maphist,"<- done (OK UNWIRE)",0,0,0,0); 2344 return 0; 2345 } 2346 2347 /* 2348 * wire case: in two passes [XXXCDC: ugly block of code here] 2349 * 2350 * 1: holding the write lock, we create any anonymous maps that need 2351 * to be created. then we clip each map entry to the region to 2352 * be wired and increment its wiring count. 2353 * 2354 * 2: we downgrade to a read lock, and call uvm_fault_wire to fault 2355 * in the pages for any newly wired area (wired_count == 1). 2356 * 2357 * downgrading to a read lock for uvm_fault_wire avoids a possible 2358 * deadlock with another thread that may have faulted on one of 2359 * the pages to be wired (it would mark the page busy, blocking 2360 * us, then in turn block on the map lock that we hold). because 2361 * of problems in the recursive lock package, we cannot upgrade 2362 * to a write lock in vm_map_lookup. thus, any actions that 2363 * require the write lock must be done beforehand. because we 2364 * keep the read lock on the map, the copy-on-write status of the 2365 * entries we modify here cannot change. 2366 */ 2367 2368 while ((entry != &map->header) && (entry->start < end)) { 2369 if (VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 2370 2371 /* 2372 * perform actions of vm_map_lookup that need the 2373 * write lock on the map: create an anonymous map 2374 * for a copy-on-write region, or an anonymous map 2375 * for a zero-fill region. (XXXCDC: submap case 2376 * ok?) 2377 */ 2378 2379 if (!UVM_ET_ISSUBMAP(entry)) { /* not submap */ 2380 if (UVM_ET_ISNEEDSCOPY(entry) && 2381 ((entry->max_protection & VM_PROT_WRITE) || 2382 (entry->object.uvm_obj == NULL))) { 2383 amap_copy(map, entry, M_WAITOK, TRUE, 2384 start, end); 2385 /* XXXCDC: wait OK? */ 2386 } 2387 } 2388 } 2389 UVM_MAP_CLIP_START(map, entry, start); 2390 UVM_MAP_CLIP_END(map, entry, end); 2391 entry->wired_count++; 2392 2393 /* 2394 * Check for holes 2395 */ 2396 2397 if (entry->protection == VM_PROT_NONE || 2398 (entry->end < end && 2399 (entry->next == &map->header || 2400 entry->next->start > entry->end))) { 2401 2402 /* 2403 * found one. amap creation actions do not need to 2404 * be undone, but the wired counts need to be restored. 2405 */ 2406 2407 while (entry != &map->header && entry->end > start) { 2408 entry->wired_count--; 2409 entry = entry->prev; 2410 } 2411 if ((lockflags & UVM_LK_EXIT) == 0) 2412 vm_map_unlock(map); 2413 UVMHIST_LOG(maphist,"<- done (INVALID WIRE)",0,0,0,0); 2414 return EINVAL; 2415 } 2416 entry = entry->next; 2417 } 2418 2419 /* 2420 * Pass 2. 2421 */ 2422 2423 #ifdef DIAGNOSTIC 2424 timestamp_save = map->timestamp; 2425 #endif 2426 vm_map_busy(map); 2427 vm_map_downgrade(map); 2428 2429 rv = 0; 2430 entry = start_entry; 2431 while (entry != &map->header && entry->start < end) { 2432 if (entry->wired_count == 1) { 2433 rv = uvm_fault_wire(map, entry->start, entry->end, 2434 VM_FAULT_WIREMAX, entry->max_protection); 2435 if (rv) { 2436 2437 /* 2438 * wiring failed. break out of the loop. 2439 * we'll clean up the map below, once we 2440 * have a write lock again. 2441 */ 2442 2443 break; 2444 } 2445 } 2446 entry = entry->next; 2447 } 2448 2449 if (rv) { /* failed? */ 2450 2451 /* 2452 * Get back to an exclusive (write) lock. 2453 */ 2454 2455 vm_map_upgrade(map); 2456 vm_map_unbusy(map); 2457 2458 #ifdef DIAGNOSTIC 2459 if (timestamp_save != map->timestamp) 2460 panic("uvm_map_pageable: stale map"); 2461 #endif 2462 2463 /* 2464 * first drop the wiring count on all the entries 2465 * which haven't actually been wired yet. 2466 */ 2467 2468 failed_entry = entry; 2469 while (entry != &map->header && entry->start < end) { 2470 entry->wired_count--; 2471 entry = entry->next; 2472 } 2473 2474 /* 2475 * now, unwire all the entries that were successfully 2476 * wired above. 2477 */ 2478 2479 entry = start_entry; 2480 while (entry != failed_entry) { 2481 entry->wired_count--; 2482 if (VM_MAPENT_ISWIRED(entry) == 0) 2483 uvm_map_entry_unwire(map, entry); 2484 entry = entry->next; 2485 } 2486 if ((lockflags & UVM_LK_EXIT) == 0) 2487 vm_map_unlock(map); 2488 UVMHIST_LOG(maphist, "<- done (RV=%d)", rv,0,0,0); 2489 return(rv); 2490 } 2491 2492 /* We are holding a read lock here. */ 2493 if ((lockflags & UVM_LK_EXIT) == 0) { 2494 vm_map_unbusy(map); 2495 vm_map_unlock_read(map); 2496 } else { 2497 2498 /* 2499 * Get back to an exclusive (write) lock. 2500 */ 2501 2502 vm_map_upgrade(map); 2503 vm_map_unbusy(map); 2504 } 2505 2506 UVMHIST_LOG(maphist,"<- done (OK WIRE)",0,0,0,0); 2507 return 0; 2508 } 2509 2510 /* 2511 * uvm_map_pageable_all: special case of uvm_map_pageable - affects 2512 * all mapped regions. 2513 * 2514 * => map must not be locked. 2515 * => if no flags are specified, all regions are unwired. 2516 * => XXXJRT: has some of the same problems as uvm_map_pageable() above. 2517 */ 2518 2519 int 2520 uvm_map_pageable_all(map, flags, limit) 2521 struct vm_map *map; 2522 int flags; 2523 vsize_t limit; 2524 { 2525 struct vm_map_entry *entry, *failed_entry; 2526 vsize_t size; 2527 int rv; 2528 #ifdef DIAGNOSTIC 2529 u_int timestamp_save; 2530 #endif 2531 UVMHIST_FUNC("uvm_map_pageable_all"); UVMHIST_CALLED(maphist); 2532 UVMHIST_LOG(maphist,"(map=0x%x,flags=0x%x)", map, flags, 0, 0); 2533 2534 KASSERT(map->flags & VM_MAP_PAGEABLE); 2535 2536 vm_map_lock(map); 2537 2538 /* 2539 * handle wiring and unwiring separately. 2540 */ 2541 2542 if (flags == 0) { /* unwire */ 2543 2544 /* 2545 * POSIX 1003.1b -- munlockall unlocks all regions, 2546 * regardless of how many times mlockall has been called. 2547 */ 2548 2549 for (entry = map->header.next; entry != &map->header; 2550 entry = entry->next) { 2551 if (VM_MAPENT_ISWIRED(entry)) 2552 uvm_map_entry_unwire(map, entry); 2553 } 2554 vm_map_modflags(map, 0, VM_MAP_WIREFUTURE); 2555 vm_map_unlock(map); 2556 UVMHIST_LOG(maphist,"<- done (OK UNWIRE)",0,0,0,0); 2557 return 0; 2558 } 2559 2560 if (flags & MCL_FUTURE) { 2561 2562 /* 2563 * must wire all future mappings; remember this. 2564 */ 2565 2566 vm_map_modflags(map, VM_MAP_WIREFUTURE, 0); 2567 } 2568 2569 if ((flags & MCL_CURRENT) == 0) { 2570 2571 /* 2572 * no more work to do! 2573 */ 2574 2575 UVMHIST_LOG(maphist,"<- done (OK no wire)",0,0,0,0); 2576 vm_map_unlock(map); 2577 return 0; 2578 } 2579 2580 /* 2581 * wire case: in three passes [XXXCDC: ugly block of code here] 2582 * 2583 * 1: holding the write lock, count all pages mapped by non-wired 2584 * entries. if this would cause us to go over our limit, we fail. 2585 * 2586 * 2: still holding the write lock, we create any anonymous maps that 2587 * need to be created. then we increment its wiring count. 2588 * 2589 * 3: we downgrade to a read lock, and call uvm_fault_wire to fault 2590 * in the pages for any newly wired area (wired_count == 1). 2591 * 2592 * downgrading to a read lock for uvm_fault_wire avoids a possible 2593 * deadlock with another thread that may have faulted on one of 2594 * the pages to be wired (it would mark the page busy, blocking 2595 * us, then in turn block on the map lock that we hold). because 2596 * of problems in the recursive lock package, we cannot upgrade 2597 * to a write lock in vm_map_lookup. thus, any actions that 2598 * require the write lock must be done beforehand. because we 2599 * keep the read lock on the map, the copy-on-write status of the 2600 * entries we modify here cannot change. 2601 */ 2602 2603 for (size = 0, entry = map->header.next; entry != &map->header; 2604 entry = entry->next) { 2605 if (entry->protection != VM_PROT_NONE && 2606 VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 2607 size += entry->end - entry->start; 2608 } 2609 } 2610 2611 if (atop(size) + uvmexp.wired > uvmexp.wiredmax) { 2612 vm_map_unlock(map); 2613 return ENOMEM; 2614 } 2615 2616 /* XXX non-pmap_wired_count case must be handled by caller */ 2617 #ifdef pmap_wired_count 2618 if (limit != 0 && 2619 (size + ptoa(pmap_wired_count(vm_map_pmap(map))) > limit)) { 2620 vm_map_unlock(map); 2621 return ENOMEM; 2622 } 2623 #endif 2624 2625 /* 2626 * Pass 2. 2627 */ 2628 2629 for (entry = map->header.next; entry != &map->header; 2630 entry = entry->next) { 2631 if (entry->protection == VM_PROT_NONE) 2632 continue; 2633 if (VM_MAPENT_ISWIRED(entry) == 0) { /* not already wired? */ 2634 2635 /* 2636 * perform actions of vm_map_lookup that need the 2637 * write lock on the map: create an anonymous map 2638 * for a copy-on-write region, or an anonymous map 2639 * for a zero-fill region. (XXXCDC: submap case 2640 * ok?) 2641 */ 2642 2643 if (!UVM_ET_ISSUBMAP(entry)) { /* not submap */ 2644 if (UVM_ET_ISNEEDSCOPY(entry) && 2645 ((entry->max_protection & VM_PROT_WRITE) || 2646 (entry->object.uvm_obj == NULL))) { 2647 amap_copy(map, entry, M_WAITOK, TRUE, 2648 entry->start, entry->end); 2649 /* XXXCDC: wait OK? */ 2650 } 2651 } 2652 } 2653 entry->wired_count++; 2654 } 2655 2656 /* 2657 * Pass 3. 2658 */ 2659 2660 #ifdef DIAGNOSTIC 2661 timestamp_save = map->timestamp; 2662 #endif 2663 vm_map_busy(map); 2664 vm_map_downgrade(map); 2665 2666 rv = 0; 2667 for (entry = map->header.next; entry != &map->header; 2668 entry = entry->next) { 2669 if (entry->wired_count == 1) { 2670 rv = uvm_fault_wire(map, entry->start, entry->end, 2671 VM_FAULT_WIREMAX, entry->max_protection); 2672 if (rv) { 2673 2674 /* 2675 * wiring failed. break out of the loop. 2676 * we'll clean up the map below, once we 2677 * have a write lock again. 2678 */ 2679 2680 break; 2681 } 2682 } 2683 } 2684 2685 if (rv) { 2686 2687 /* 2688 * Get back an exclusive (write) lock. 2689 */ 2690 2691 vm_map_upgrade(map); 2692 vm_map_unbusy(map); 2693 2694 #ifdef DIAGNOSTIC 2695 if (timestamp_save != map->timestamp) 2696 panic("uvm_map_pageable_all: stale map"); 2697 #endif 2698 2699 /* 2700 * first drop the wiring count on all the entries 2701 * which haven't actually been wired yet. 2702 * 2703 * Skip VM_PROT_NONE entries like we did above. 2704 */ 2705 2706 failed_entry = entry; 2707 for (/* nothing */; entry != &map->header; 2708 entry = entry->next) { 2709 if (entry->protection == VM_PROT_NONE) 2710 continue; 2711 entry->wired_count--; 2712 } 2713 2714 /* 2715 * now, unwire all the entries that were successfully 2716 * wired above. 2717 * 2718 * Skip VM_PROT_NONE entries like we did above. 2719 */ 2720 2721 for (entry = map->header.next; entry != failed_entry; 2722 entry = entry->next) { 2723 if (entry->protection == VM_PROT_NONE) 2724 continue; 2725 entry->wired_count--; 2726 if (VM_MAPENT_ISWIRED(entry)) 2727 uvm_map_entry_unwire(map, entry); 2728 } 2729 vm_map_unlock(map); 2730 UVMHIST_LOG(maphist,"<- done (RV=%d)", rv,0,0,0); 2731 return (rv); 2732 } 2733 2734 /* We are holding a read lock here. */ 2735 vm_map_unbusy(map); 2736 vm_map_unlock_read(map); 2737 2738 UVMHIST_LOG(maphist,"<- done (OK WIRE)",0,0,0,0); 2739 return 0; 2740 } 2741 2742 /* 2743 * uvm_map_clean: clean out a map range 2744 * 2745 * => valid flags: 2746 * if (flags & PGO_CLEANIT): dirty pages are cleaned first 2747 * if (flags & PGO_SYNCIO): dirty pages are written synchronously 2748 * if (flags & PGO_DEACTIVATE): any cached pages are deactivated after clean 2749 * if (flags & PGO_FREE): any cached pages are freed after clean 2750 * => returns an error if any part of the specified range isn't mapped 2751 * => never a need to flush amap layer since the anonymous memory has 2752 * no permanent home, but may deactivate pages there 2753 * => called from sys_msync() and sys_madvise() 2754 * => caller must not write-lock map (read OK). 2755 * => we may sleep while cleaning if SYNCIO [with map read-locked] 2756 */ 2757 2758 int 2759 uvm_map_clean(map, start, end, flags) 2760 struct vm_map *map; 2761 vaddr_t start, end; 2762 int flags; 2763 { 2764 struct vm_map_entry *current, *entry; 2765 struct uvm_object *uobj; 2766 struct vm_amap *amap; 2767 struct vm_anon *anon; 2768 struct vm_page *pg; 2769 vaddr_t offset; 2770 vsize_t size; 2771 int error, refs; 2772 UVMHIST_FUNC("uvm_map_clean"); UVMHIST_CALLED(maphist); 2773 2774 UVMHIST_LOG(maphist,"(map=0x%x,start=0x%x,end=0x%x,flags=0x%x)", 2775 map, start, end, flags); 2776 KASSERT((flags & (PGO_FREE|PGO_DEACTIVATE)) != 2777 (PGO_FREE|PGO_DEACTIVATE)); 2778 2779 vm_map_lock_read(map); 2780 VM_MAP_RANGE_CHECK(map, start, end); 2781 if (uvm_map_lookup_entry(map, start, &entry) == FALSE) { 2782 vm_map_unlock_read(map); 2783 return EFAULT; 2784 } 2785 2786 /* 2787 * Make a first pass to check for holes. 2788 */ 2789 2790 for (current = entry; current->start < end; current = current->next) { 2791 if (UVM_ET_ISSUBMAP(current)) { 2792 vm_map_unlock_read(map); 2793 return EINVAL; 2794 } 2795 if (end <= current->end) { 2796 break; 2797 } 2798 if (current->end != current->next->start) { 2799 vm_map_unlock_read(map); 2800 return EFAULT; 2801 } 2802 } 2803 2804 error = 0; 2805 for (current = entry; start < end; current = current->next) { 2806 amap = current->aref.ar_amap; /* top layer */ 2807 uobj = current->object.uvm_obj; /* bottom layer */ 2808 KASSERT(start >= current->start); 2809 2810 /* 2811 * No amap cleaning necessary if: 2812 * 2813 * (1) There's no amap. 2814 * 2815 * (2) We're not deactivating or freeing pages. 2816 */ 2817 2818 if (amap == NULL || (flags & (PGO_DEACTIVATE|PGO_FREE)) == 0) 2819 goto flush_object; 2820 2821 amap_lock(amap); 2822 offset = start - current->start; 2823 size = MIN(end, current->end) - start; 2824 for ( ; size != 0; size -= PAGE_SIZE, offset += PAGE_SIZE) { 2825 anon = amap_lookup(¤t->aref, offset); 2826 if (anon == NULL) 2827 continue; 2828 2829 simple_lock(&anon->an_lock); 2830 pg = anon->u.an_page; 2831 if (pg == NULL) { 2832 simple_unlock(&anon->an_lock); 2833 continue; 2834 } 2835 2836 switch (flags & (PGO_CLEANIT|PGO_FREE|PGO_DEACTIVATE)) { 2837 2838 /* 2839 * In these first 3 cases, we just deactivate the page. 2840 */ 2841 2842 case PGO_CLEANIT|PGO_FREE: 2843 case PGO_CLEANIT|PGO_DEACTIVATE: 2844 case PGO_DEACTIVATE: 2845 deactivate_it: 2846 /* 2847 * skip the page if it's loaned or wired, 2848 * since it shouldn't be on a paging queue 2849 * at all in these cases. 2850 */ 2851 2852 uvm_lock_pageq(); 2853 if (pg->loan_count != 0 || 2854 pg->wire_count != 0) { 2855 uvm_unlock_pageq(); 2856 simple_unlock(&anon->an_lock); 2857 continue; 2858 } 2859 KASSERT(pg->uanon == anon); 2860 pmap_clear_reference(pg); 2861 uvm_pagedeactivate(pg); 2862 uvm_unlock_pageq(); 2863 simple_unlock(&anon->an_lock); 2864 continue; 2865 2866 case PGO_FREE: 2867 2868 /* 2869 * If there are multiple references to 2870 * the amap, just deactivate the page. 2871 */ 2872 2873 if (amap_refs(amap) > 1) 2874 goto deactivate_it; 2875 2876 /* skip the page if it's wired */ 2877 if (pg->wire_count != 0) { 2878 simple_unlock(&anon->an_lock); 2879 continue; 2880 } 2881 amap_unadd(¤t->aref, offset); 2882 refs = --anon->an_ref; 2883 simple_unlock(&anon->an_lock); 2884 if (refs == 0) 2885 uvm_anfree(anon); 2886 continue; 2887 } 2888 } 2889 amap_unlock(amap); 2890 2891 flush_object: 2892 /* 2893 * flush pages if we've got a valid backing object. 2894 * note that we must always clean object pages before 2895 * freeing them since otherwise we could reveal stale 2896 * data from files. 2897 */ 2898 2899 offset = current->offset + (start - current->start); 2900 size = MIN(end, current->end) - start; 2901 if (uobj != NULL) { 2902 simple_lock(&uobj->vmobjlock); 2903 if (uobj->pgops->pgo_put != NULL) 2904 error = (uobj->pgops->pgo_put)(uobj, offset, 2905 offset + size, flags | PGO_CLEANIT); 2906 else 2907 error = 0; 2908 } 2909 start += size; 2910 } 2911 vm_map_unlock_read(map); 2912 return (error); 2913 } 2914 2915 2916 /* 2917 * uvm_map_checkprot: check protection in map 2918 * 2919 * => must allow specified protection in a fully allocated region. 2920 * => map must be read or write locked by caller. 2921 */ 2922 2923 boolean_t 2924 uvm_map_checkprot(map, start, end, protection) 2925 struct vm_map * map; 2926 vaddr_t start, end; 2927 vm_prot_t protection; 2928 { 2929 struct vm_map_entry *entry; 2930 struct vm_map_entry *tmp_entry; 2931 2932 if (!uvm_map_lookup_entry(map, start, &tmp_entry)) { 2933 return(FALSE); 2934 } 2935 entry = tmp_entry; 2936 while (start < end) { 2937 if (entry == &map->header) { 2938 return(FALSE); 2939 } 2940 2941 /* 2942 * no holes allowed 2943 */ 2944 2945 if (start < entry->start) { 2946 return(FALSE); 2947 } 2948 2949 /* 2950 * check protection associated with entry 2951 */ 2952 2953 if ((entry->protection & protection) != protection) { 2954 return(FALSE); 2955 } 2956 start = entry->end; 2957 entry = entry->next; 2958 } 2959 return(TRUE); 2960 } 2961 2962 /* 2963 * uvmspace_alloc: allocate a vmspace structure. 2964 * 2965 * - structure includes vm_map and pmap 2966 * - XXX: no locking on this structure 2967 * - refcnt set to 1, rest must be init'd by caller 2968 */ 2969 struct vmspace * 2970 uvmspace_alloc(min, max) 2971 vaddr_t min, max; 2972 { 2973 struct vmspace *vm; 2974 UVMHIST_FUNC("uvmspace_alloc"); UVMHIST_CALLED(maphist); 2975 2976 vm = pool_get(&uvm_vmspace_pool, PR_WAITOK); 2977 uvmspace_init(vm, NULL, min, max); 2978 UVMHIST_LOG(maphist,"<- done (vm=0x%x)", vm,0,0,0); 2979 return (vm); 2980 } 2981 2982 /* 2983 * uvmspace_init: initialize a vmspace structure. 2984 * 2985 * - XXX: no locking on this structure 2986 * - refcnt set to 1, rest must be init'd by caller 2987 */ 2988 void 2989 uvmspace_init(vm, pmap, min, max) 2990 struct vmspace *vm; 2991 struct pmap *pmap; 2992 vaddr_t min, max; 2993 { 2994 UVMHIST_FUNC("uvmspace_init"); UVMHIST_CALLED(maphist); 2995 2996 memset(vm, 0, sizeof(*vm)); 2997 uvm_map_setup(&vm->vm_map, min, max, VM_MAP_PAGEABLE 2998 #ifdef __USING_TOPDOWN_VM 2999 | VM_MAP_TOPDOWN 3000 #endif 3001 ); 3002 if (pmap) 3003 pmap_reference(pmap); 3004 else 3005 pmap = pmap_create(); 3006 vm->vm_map.pmap = pmap; 3007 vm->vm_refcnt = 1; 3008 UVMHIST_LOG(maphist,"<- done",0,0,0,0); 3009 } 3010 3011 /* 3012 * uvmspace_share: share a vmspace between two proceses 3013 * 3014 * - XXX: no locking on vmspace 3015 * - used for vfork, threads(?) 3016 */ 3017 3018 void 3019 uvmspace_share(p1, p2) 3020 struct proc *p1, *p2; 3021 { 3022 p2->p_vmspace = p1->p_vmspace; 3023 p1->p_vmspace->vm_refcnt++; 3024 } 3025 3026 /* 3027 * uvmspace_unshare: ensure that process "p" has its own, unshared, vmspace 3028 * 3029 * - XXX: no locking on vmspace 3030 */ 3031 3032 void 3033 uvmspace_unshare(l) 3034 struct lwp *l; 3035 { 3036 struct proc *p = l->l_proc; 3037 struct vmspace *nvm, *ovm = p->p_vmspace; 3038 3039 if (ovm->vm_refcnt == 1) 3040 /* nothing to do: vmspace isn't shared in the first place */ 3041 return; 3042 3043 /* make a new vmspace, still holding old one */ 3044 nvm = uvmspace_fork(ovm); 3045 3046 pmap_deactivate(l); /* unbind old vmspace */ 3047 p->p_vmspace = nvm; 3048 pmap_activate(l); /* switch to new vmspace */ 3049 3050 uvmspace_free(ovm); /* drop reference to old vmspace */ 3051 } 3052 3053 /* 3054 * uvmspace_exec: the process wants to exec a new program 3055 * 3056 * - XXX: no locking on vmspace 3057 */ 3058 3059 void 3060 uvmspace_exec(l, start, end) 3061 struct lwp *l; 3062 vaddr_t start, end; 3063 { 3064 struct proc *p = l->l_proc; 3065 struct vmspace *nvm, *ovm = p->p_vmspace; 3066 struct vm_map *map = &ovm->vm_map; 3067 3068 #ifdef __sparc__ 3069 /* XXX cgd 960926: the sparc #ifdef should be a MD hook */ 3070 kill_user_windows(l); /* before stack addresses go away */ 3071 #endif 3072 3073 /* 3074 * see if more than one process is using this vmspace... 3075 */ 3076 3077 if (ovm->vm_refcnt == 1) { 3078 3079 /* 3080 * if p is the only process using its vmspace then we can safely 3081 * recycle that vmspace for the program that is being exec'd. 3082 */ 3083 3084 #ifdef SYSVSHM 3085 /* 3086 * SYSV SHM semantics require us to kill all segments on an exec 3087 */ 3088 3089 if (ovm->vm_shm) 3090 shmexit(ovm); 3091 #endif 3092 3093 /* 3094 * POSIX 1003.1b -- "lock future mappings" is revoked 3095 * when a process execs another program image. 3096 */ 3097 3098 vm_map_modflags(map, 0, VM_MAP_WIREFUTURE); 3099 3100 /* 3101 * now unmap the old program 3102 */ 3103 3104 pmap_remove_all(map->pmap); 3105 uvm_unmap(map, map->min_offset, map->max_offset); 3106 3107 /* 3108 * resize the map 3109 */ 3110 3111 map->min_offset = start; 3112 map->max_offset = end; 3113 } else { 3114 3115 /* 3116 * p's vmspace is being shared, so we can't reuse it for p since 3117 * it is still being used for others. allocate a new vmspace 3118 * for p 3119 */ 3120 3121 nvm = uvmspace_alloc(start, end); 3122 3123 /* 3124 * install new vmspace and drop our ref to the old one. 3125 */ 3126 3127 pmap_deactivate(l); 3128 p->p_vmspace = nvm; 3129 pmap_activate(l); 3130 3131 uvmspace_free(ovm); 3132 } 3133 } 3134 3135 /* 3136 * uvmspace_free: free a vmspace data structure 3137 * 3138 * - XXX: no locking on vmspace 3139 */ 3140 3141 void 3142 uvmspace_free(vm) 3143 struct vmspace *vm; 3144 { 3145 struct vm_map_entry *dead_entries; 3146 struct vm_map *map; 3147 UVMHIST_FUNC("uvmspace_free"); UVMHIST_CALLED(maphist); 3148 3149 UVMHIST_LOG(maphist,"(vm=0x%x) ref=%d", vm, vm->vm_refcnt,0,0); 3150 if (--vm->vm_refcnt > 0) { 3151 return; 3152 } 3153 3154 /* 3155 * at this point, there should be no other references to the map. 3156 * delete all of the mappings, then destroy the pmap. 3157 */ 3158 3159 map = &vm->vm_map; 3160 map->flags |= VM_MAP_DYING; 3161 pmap_remove_all(map->pmap); 3162 #ifdef SYSVSHM 3163 /* Get rid of any SYSV shared memory segments. */ 3164 if (vm->vm_shm != NULL) 3165 shmexit(vm); 3166 #endif 3167 if (map->nentries) { 3168 uvm_unmap_remove(map, map->min_offset, map->max_offset, 3169 &dead_entries); 3170 if (dead_entries != NULL) 3171 uvm_unmap_detach(dead_entries, 0); 3172 } 3173 pmap_destroy(map->pmap); 3174 pool_put(&uvm_vmspace_pool, vm); 3175 } 3176 3177 /* 3178 * F O R K - m a i n e n t r y p o i n t 3179 */ 3180 /* 3181 * uvmspace_fork: fork a process' main map 3182 * 3183 * => create a new vmspace for child process from parent. 3184 * => parent's map must not be locked. 3185 */ 3186 3187 struct vmspace * 3188 uvmspace_fork(vm1) 3189 struct vmspace *vm1; 3190 { 3191 struct vmspace *vm2; 3192 struct vm_map *old_map = &vm1->vm_map; 3193 struct vm_map *new_map; 3194 struct vm_map_entry *old_entry; 3195 struct vm_map_entry *new_entry; 3196 UVMHIST_FUNC("uvmspace_fork"); UVMHIST_CALLED(maphist); 3197 3198 vm_map_lock(old_map); 3199 3200 vm2 = uvmspace_alloc(old_map->min_offset, old_map->max_offset); 3201 memcpy(&vm2->vm_startcopy, &vm1->vm_startcopy, 3202 (caddr_t) (vm1 + 1) - (caddr_t) &vm1->vm_startcopy); 3203 new_map = &vm2->vm_map; /* XXX */ 3204 3205 old_entry = old_map->header.next; 3206 3207 /* 3208 * go entry-by-entry 3209 */ 3210 3211 while (old_entry != &old_map->header) { 3212 3213 /* 3214 * first, some sanity checks on the old entry 3215 */ 3216 3217 KASSERT(!UVM_ET_ISSUBMAP(old_entry)); 3218 KASSERT(UVM_ET_ISCOPYONWRITE(old_entry) || 3219 !UVM_ET_ISNEEDSCOPY(old_entry)); 3220 3221 switch (old_entry->inheritance) { 3222 case MAP_INHERIT_NONE: 3223 3224 /* 3225 * drop the mapping 3226 */ 3227 3228 break; 3229 3230 case MAP_INHERIT_SHARE: 3231 3232 /* 3233 * share the mapping: this means we want the old and 3234 * new entries to share amaps and backing objects. 3235 */ 3236 /* 3237 * if the old_entry needs a new amap (due to prev fork) 3238 * then we need to allocate it now so that we have 3239 * something we own to share with the new_entry. [in 3240 * other words, we need to clear needs_copy] 3241 */ 3242 3243 if (UVM_ET_ISNEEDSCOPY(old_entry)) { 3244 /* get our own amap, clears needs_copy */ 3245 amap_copy(old_map, old_entry, M_WAITOK, FALSE, 3246 0, 0); 3247 /* XXXCDC: WAITOK??? */ 3248 } 3249 3250 new_entry = uvm_mapent_alloc(new_map, 0); 3251 /* old_entry -> new_entry */ 3252 uvm_mapent_copy(old_entry, new_entry); 3253 3254 /* new pmap has nothing wired in it */ 3255 new_entry->wired_count = 0; 3256 3257 /* 3258 * gain reference to object backing the map (can't 3259 * be a submap, already checked this case). 3260 */ 3261 3262 if (new_entry->aref.ar_amap) 3263 uvm_map_reference_amap(new_entry, AMAP_SHARED); 3264 3265 if (new_entry->object.uvm_obj && 3266 new_entry->object.uvm_obj->pgops->pgo_reference) 3267 new_entry->object.uvm_obj-> 3268 pgops->pgo_reference( 3269 new_entry->object.uvm_obj); 3270 3271 /* insert entry at end of new_map's entry list */ 3272 uvm_map_entry_link(new_map, new_map->header.prev, 3273 new_entry); 3274 3275 break; 3276 3277 case MAP_INHERIT_COPY: 3278 3279 /* 3280 * copy-on-write the mapping (using mmap's 3281 * MAP_PRIVATE semantics) 3282 * 3283 * allocate new_entry, adjust reference counts. 3284 * (note that new references are read-only). 3285 */ 3286 3287 new_entry = uvm_mapent_alloc(new_map, 0); 3288 /* old_entry -> new_entry */ 3289 uvm_mapent_copy(old_entry, new_entry); 3290 3291 if (new_entry->aref.ar_amap) 3292 uvm_map_reference_amap(new_entry, 0); 3293 3294 if (new_entry->object.uvm_obj && 3295 new_entry->object.uvm_obj->pgops->pgo_reference) 3296 new_entry->object.uvm_obj->pgops->pgo_reference 3297 (new_entry->object.uvm_obj); 3298 3299 /* new pmap has nothing wired in it */ 3300 new_entry->wired_count = 0; 3301 3302 new_entry->etype |= 3303 (UVM_ET_COPYONWRITE|UVM_ET_NEEDSCOPY); 3304 uvm_map_entry_link(new_map, new_map->header.prev, 3305 new_entry); 3306 3307 /* 3308 * the new entry will need an amap. it will either 3309 * need to be copied from the old entry or created 3310 * from scratch (if the old entry does not have an 3311 * amap). can we defer this process until later 3312 * (by setting "needs_copy") or do we need to copy 3313 * the amap now? 3314 * 3315 * we must copy the amap now if any of the following 3316 * conditions hold: 3317 * 1. the old entry has an amap and that amap is 3318 * being shared. this means that the old (parent) 3319 * process is sharing the amap with another 3320 * process. if we do not clear needs_copy here 3321 * we will end up in a situation where both the 3322 * parent and child process are refering to the 3323 * same amap with "needs_copy" set. if the 3324 * parent write-faults, the fault routine will 3325 * clear "needs_copy" in the parent by allocating 3326 * a new amap. this is wrong because the 3327 * parent is supposed to be sharing the old amap 3328 * and the new amap will break that. 3329 * 3330 * 2. if the old entry has an amap and a non-zero 3331 * wire count then we are going to have to call 3332 * amap_cow_now to avoid page faults in the 3333 * parent process. since amap_cow_now requires 3334 * "needs_copy" to be clear we might as well 3335 * clear it here as well. 3336 * 3337 */ 3338 3339 if (old_entry->aref.ar_amap != NULL) { 3340 if ((amap_flags(old_entry->aref.ar_amap) & 3341 AMAP_SHARED) != 0 || 3342 VM_MAPENT_ISWIRED(old_entry)) { 3343 3344 amap_copy(new_map, new_entry, M_WAITOK, 3345 FALSE, 0, 0); 3346 /* XXXCDC: M_WAITOK ... ok? */ 3347 } 3348 } 3349 3350 /* 3351 * if the parent's entry is wired down, then the 3352 * parent process does not want page faults on 3353 * access to that memory. this means that we 3354 * cannot do copy-on-write because we can't write 3355 * protect the old entry. in this case we 3356 * resolve all copy-on-write faults now, using 3357 * amap_cow_now. note that we have already 3358 * allocated any needed amap (above). 3359 */ 3360 3361 if (VM_MAPENT_ISWIRED(old_entry)) { 3362 3363 /* 3364 * resolve all copy-on-write faults now 3365 * (note that there is nothing to do if 3366 * the old mapping does not have an amap). 3367 */ 3368 if (old_entry->aref.ar_amap) 3369 amap_cow_now(new_map, new_entry); 3370 3371 } else { 3372 3373 /* 3374 * setup mappings to trigger copy-on-write faults 3375 * we must write-protect the parent if it has 3376 * an amap and it is not already "needs_copy"... 3377 * if it is already "needs_copy" then the parent 3378 * has already been write-protected by a previous 3379 * fork operation. 3380 */ 3381 3382 if (old_entry->aref.ar_amap && 3383 !UVM_ET_ISNEEDSCOPY(old_entry)) { 3384 if (old_entry->max_protection & VM_PROT_WRITE) { 3385 pmap_protect(old_map->pmap, 3386 old_entry->start, 3387 old_entry->end, 3388 old_entry->protection & 3389 ~VM_PROT_WRITE); 3390 pmap_update(old_map->pmap); 3391 } 3392 old_entry->etype |= UVM_ET_NEEDSCOPY; 3393 } 3394 } 3395 break; 3396 } /* end of switch statement */ 3397 old_entry = old_entry->next; 3398 } 3399 3400 new_map->size = old_map->size; 3401 vm_map_unlock(old_map); 3402 3403 #ifdef SYSVSHM 3404 if (vm1->vm_shm) 3405 shmfork(vm1, vm2); 3406 #endif 3407 3408 #ifdef PMAP_FORK 3409 pmap_fork(vm1->vm_map.pmap, vm2->vm_map.pmap); 3410 #endif 3411 3412 UVMHIST_LOG(maphist,"<- done",0,0,0,0); 3413 return(vm2); 3414 } 3415 3416 3417 #if defined(DDB) 3418 3419 /* 3420 * DDB hooks 3421 */ 3422 3423 /* 3424 * uvm_map_printit: actually prints the map 3425 */ 3426 3427 void 3428 uvm_map_printit(map, full, pr) 3429 struct vm_map *map; 3430 boolean_t full; 3431 void (*pr) __P((const char *, ...)); 3432 { 3433 struct vm_map_entry *entry; 3434 3435 (*pr)("MAP %p: [0x%lx->0x%lx]\n", map, map->min_offset,map->max_offset); 3436 (*pr)("\t#ent=%d, sz=%d, ref=%d, version=%d, flags=0x%x\n", 3437 map->nentries, map->size, map->ref_count, map->timestamp, 3438 map->flags); 3439 (*pr)("\tpmap=%p(resident=%d)\n", map->pmap, 3440 pmap_resident_count(map->pmap)); 3441 if (!full) 3442 return; 3443 for (entry = map->header.next; entry != &map->header; 3444 entry = entry->next) { 3445 (*pr)(" - %p: 0x%lx->0x%lx: obj=%p/0x%llx, amap=%p/%d\n", 3446 entry, entry->start, entry->end, entry->object.uvm_obj, 3447 (long long)entry->offset, entry->aref.ar_amap, 3448 entry->aref.ar_pageoff); 3449 (*pr)( 3450 "\tsubmap=%c, cow=%c, nc=%c, prot(max)=%d/%d, inh=%d, " 3451 "wc=%d, adv=%d\n", 3452 (entry->etype & UVM_ET_SUBMAP) ? 'T' : 'F', 3453 (entry->etype & UVM_ET_COPYONWRITE) ? 'T' : 'F', 3454 (entry->etype & UVM_ET_NEEDSCOPY) ? 'T' : 'F', 3455 entry->protection, entry->max_protection, 3456 entry->inheritance, entry->wired_count, entry->advice); 3457 } 3458 } 3459 3460 /* 3461 * uvm_object_printit: actually prints the object 3462 */ 3463 3464 void 3465 uvm_object_printit(uobj, full, pr) 3466 struct uvm_object *uobj; 3467 boolean_t full; 3468 void (*pr) __P((const char *, ...)); 3469 { 3470 struct vm_page *pg; 3471 int cnt = 0; 3472 3473 (*pr)("OBJECT %p: locked=%d, pgops=%p, npages=%d, ", 3474 uobj, uobj->vmobjlock.lock_data, uobj->pgops, uobj->uo_npages); 3475 if (UVM_OBJ_IS_KERN_OBJECT(uobj)) 3476 (*pr)("refs=<SYSTEM>\n"); 3477 else 3478 (*pr)("refs=%d\n", uobj->uo_refs); 3479 3480 if (!full) { 3481 return; 3482 } 3483 (*pr)(" PAGES <pg,offset>:\n "); 3484 TAILQ_FOREACH(pg, &uobj->memq, listq) { 3485 cnt++; 3486 (*pr)("<%p,0x%llx> ", pg, (long long)pg->offset); 3487 if ((cnt % 3) == 0) { 3488 (*pr)("\n "); 3489 } 3490 } 3491 if ((cnt % 3) != 0) { 3492 (*pr)("\n"); 3493 } 3494 } 3495 3496 /* 3497 * uvm_page_printit: actually print the page 3498 */ 3499 3500 static const char page_flagbits[] = 3501 "\20\1BUSY\2WANTED\3TABLED\4CLEAN\5PAGEOUT\6RELEASED\7FAKE\10RDONLY" 3502 "\11ZERO\15PAGER1"; 3503 static const char page_pqflagbits[] = 3504 "\20\1FREE\2INACTIVE\3ACTIVE\5ANON\6AOBJ"; 3505 3506 void 3507 uvm_page_printit(pg, full, pr) 3508 struct vm_page *pg; 3509 boolean_t full; 3510 void (*pr) __P((const char *, ...)); 3511 { 3512 struct vm_page *tpg; 3513 struct uvm_object *uobj; 3514 struct pglist *pgl; 3515 char pgbuf[128]; 3516 char pqbuf[128]; 3517 3518 (*pr)("PAGE %p:\n", pg); 3519 bitmask_snprintf(pg->flags, page_flagbits, pgbuf, sizeof(pgbuf)); 3520 bitmask_snprintf(pg->pqflags, page_pqflagbits, pqbuf, sizeof(pqbuf)); 3521 (*pr)(" flags=%s, pqflags=%s, wire_count=%d, pa=0x%lx\n", 3522 pgbuf, pqbuf, pg->wire_count, (long)pg->phys_addr); 3523 (*pr)(" uobject=%p, uanon=%p, offset=0x%llx loan_count=%d\n", 3524 pg->uobject, pg->uanon, (long long)pg->offset, pg->loan_count); 3525 #if defined(UVM_PAGE_TRKOWN) 3526 if (pg->flags & PG_BUSY) 3527 (*pr)(" owning process = %d, tag=%s\n", 3528 pg->owner, pg->owner_tag); 3529 else 3530 (*pr)(" page not busy, no owner\n"); 3531 #else 3532 (*pr)(" [page ownership tracking disabled]\n"); 3533 #endif 3534 3535 if (!full) 3536 return; 3537 3538 /* cross-verify object/anon */ 3539 if ((pg->pqflags & PQ_FREE) == 0) { 3540 if (pg->pqflags & PQ_ANON) { 3541 if (pg->uanon == NULL || pg->uanon->u.an_page != pg) 3542 (*pr)(" >>> ANON DOES NOT POINT HERE <<< (%p)\n", 3543 (pg->uanon) ? pg->uanon->u.an_page : NULL); 3544 else 3545 (*pr)(" anon backpointer is OK\n"); 3546 } else { 3547 uobj = pg->uobject; 3548 if (uobj) { 3549 (*pr)(" checking object list\n"); 3550 TAILQ_FOREACH(tpg, &uobj->memq, listq) { 3551 if (tpg == pg) { 3552 break; 3553 } 3554 } 3555 if (tpg) 3556 (*pr)(" page found on object list\n"); 3557 else 3558 (*pr)(" >>> PAGE NOT FOUND ON OBJECT LIST! <<<\n"); 3559 } 3560 } 3561 } 3562 3563 /* cross-verify page queue */ 3564 if (pg->pqflags & PQ_FREE) { 3565 int fl = uvm_page_lookup_freelist(pg); 3566 int color = VM_PGCOLOR_BUCKET(pg); 3567 pgl = &uvm.page_free[fl].pgfl_buckets[color].pgfl_queues[ 3568 ((pg)->flags & PG_ZERO) ? PGFL_ZEROS : PGFL_UNKNOWN]; 3569 } else if (pg->pqflags & PQ_INACTIVE) { 3570 pgl = &uvm.page_inactive; 3571 } else if (pg->pqflags & PQ_ACTIVE) { 3572 pgl = &uvm.page_active; 3573 } else { 3574 pgl = NULL; 3575 } 3576 3577 if (pgl) { 3578 (*pr)(" checking pageq list\n"); 3579 TAILQ_FOREACH(tpg, pgl, pageq) { 3580 if (tpg == pg) { 3581 break; 3582 } 3583 } 3584 if (tpg) 3585 (*pr)(" page found on pageq list\n"); 3586 else 3587 (*pr)(" >>> PAGE NOT FOUND ON PAGEQ LIST! <<<\n"); 3588 } 3589 } 3590 #endif 3591