The Design and Implementation of the FreeBSD Operating System, Second Edition
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FreeBSD/Linux Kernel Cross Reference
sys/vm/vm_contig.c

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    1 /*-
    2  * Copyright (c) 1991 Regents of the University of California.
    3  * All rights reserved.
    4  *
    5  * This code is derived from software contributed to Berkeley by
    6  * The Mach Operating System project at Carnegie-Mellon University.
    7  *
    8  * Redistribution and use in source and binary forms, with or without
    9  * modification, are permitted provided that the following conditions
   10  * are met:
   11  * 1. Redistributions of source code must retain the above copyright
   12  *    notice, this list of conditions and the following disclaimer.
   13  * 2. Redistributions in binary form must reproduce the above copyright
   14  *    notice, this list of conditions and the following disclaimer in the
   15  *    documentation and/or other materials provided with the distribution.
   16  * 4. Neither the name of the University nor the names of its contributors
   17  *    may be used to endorse or promote products derived from this software
   18  *    without specific prior written permission.
   19  *
   20  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
   21  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
   22  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
   23  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
   24  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
   25  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
   26  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
   27  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   28  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
   29  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
   30  * SUCH DAMAGE.
   31  *
   32  *      from: @(#)vm_page.c     7.4 (Berkeley) 5/7/91
   33  */
   34 
   35 /*-
   36  * Copyright (c) 1987, 1990 Carnegie-Mellon University.
   37  * All rights reserved.
   38  *
   39  * Authors: Avadis Tevanian, Jr., Michael Wayne Young
   40  *
   41  * Permission to use, copy, modify and distribute this software and
   42  * its documentation is hereby granted, provided that both the copyright
   43  * notice and this permission notice appear in all copies of the
   44  * software, derivative works or modified versions, and any portions
   45  * thereof, and that both notices appear in supporting documentation.
   46  *
   47  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
   48  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
   49  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
   50  *
   51  * Carnegie Mellon requests users of this software to return to
   52  *
   53  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
   54  *  School of Computer Science
   55  *  Carnegie Mellon University
   56  *  Pittsburgh PA 15213-3890
   57  *
   58  * any improvements or extensions that they make and grant Carnegie the
   59  * rights to redistribute these changes.
   60  */
   61 
   62 #include <sys/cdefs.h>
   63 __FBSDID("$FreeBSD: releng/6.0/sys/vm/vm_contig.c 149087 2005-08-15 14:28:48Z tegge $");
   64 
   65 #include <sys/param.h>
   66 #include <sys/systm.h>
   67 #include <sys/lock.h>
   68 #include <sys/malloc.h>
   69 #include <sys/mutex.h>
   70 #include <sys/proc.h>
   71 #include <sys/kernel.h>
   72 #include <sys/linker_set.h>
   73 #include <sys/sysctl.h>
   74 #include <sys/vmmeter.h>
   75 #include <sys/vnode.h>
   76 
   77 #include <vm/vm.h>
   78 #include <vm/vm_param.h>
   79 #include <vm/vm_kern.h>
   80 #include <vm/pmap.h>
   81 #include <vm/vm_map.h>
   82 #include <vm/vm_object.h>
   83 #include <vm/vm_page.h>
   84 #include <vm/vm_pageout.h>
   85 #include <vm/vm_pager.h>
   86 #include <vm/vm_extern.h>
   87 
   88 static int
   89 vm_contig_launder_page(vm_page_t m)
   90 {
   91         vm_object_t object;
   92         vm_page_t m_tmp;
   93         struct vnode *vp;
   94 
   95         object = m->object;
   96         if (!VM_OBJECT_TRYLOCK(object))
   97                 return (EAGAIN);
   98         if (vm_page_sleep_if_busy(m, TRUE, "vpctw0")) {
   99                 VM_OBJECT_UNLOCK(object);
  100                 vm_page_lock_queues();
  101                 return (EBUSY);
  102         }
  103         vm_page_test_dirty(m);
  104         if (m->dirty == 0 && m->hold_count == 0)
  105                 pmap_remove_all(m);
  106         if (m->dirty) {
  107                 if (object->type == OBJT_VNODE) {
  108                         vm_page_unlock_queues();
  109                         vp = object->handle;
  110                         VM_OBJECT_UNLOCK(object);
  111                         vn_lock(vp, LK_EXCLUSIVE | LK_RETRY, curthread);
  112                         VM_OBJECT_LOCK(object);
  113                         vm_object_page_clean(object, 0, 0, OBJPC_SYNC);
  114                         VM_OBJECT_UNLOCK(object);
  115                         VOP_UNLOCK(vp, 0, curthread);
  116                         vm_page_lock_queues();
  117                         return (0);
  118                 } else if (object->type == OBJT_SWAP ||
  119                            object->type == OBJT_DEFAULT) {
  120                         m_tmp = m;
  121                         vm_pageout_flush(&m_tmp, 1, VM_PAGER_PUT_SYNC);
  122                         VM_OBJECT_UNLOCK(object);
  123                         return (0);
  124                 }
  125         } else if (m->hold_count == 0)
  126                 vm_page_cache(m);
  127         VM_OBJECT_UNLOCK(object);
  128         return (0);
  129 }
  130 
  131 static int
  132 vm_contig_launder(int queue)
  133 {
  134         vm_page_t m, next;
  135         int error;
  136 
  137         for (m = TAILQ_FIRST(&vm_page_queues[queue].pl); m != NULL; m = next) {
  138                 next = TAILQ_NEXT(m, pageq);
  139 
  140                 /* Skip marker pages */
  141                 if ((m->flags & PG_MARKER) != 0)
  142                         continue;
  143 
  144                 KASSERT(m->queue == queue,
  145                     ("vm_contig_launder: page %p's queue is not %d", m, queue));
  146                 error = vm_contig_launder_page(m);
  147                 if (error == 0)
  148                         return (TRUE);
  149                 if (error == EBUSY)
  150                         return (FALSE);
  151         }
  152         return (FALSE);
  153 }
  154 
  155 /*
  156  * This interface is for merging with malloc() someday.
  157  * Even if we never implement compaction so that contiguous allocation
  158  * works after initialization time, malloc()'s data structures are good
  159  * for statistics and for allocations of less than a page.
  160  */
  161 static void *
  162 contigmalloc1(
  163         unsigned long size,     /* should be size_t here and for malloc() */
  164         struct malloc_type *type,
  165         int flags,
  166         vm_paddr_t low,
  167         vm_paddr_t high,
  168         unsigned long alignment,
  169         unsigned long boundary,
  170         vm_map_t map)
  171 {
  172         int i, start;
  173         vm_paddr_t phys;
  174         vm_object_t object;
  175         vm_offset_t addr, tmp_addr;
  176         int pass, pqtype;
  177         int inactl, actl, inactmax, actmax;
  178         vm_page_t pga = vm_page_array;
  179 
  180         size = round_page(size);
  181         if (size == 0)
  182                 panic("contigmalloc1: size must not be 0");
  183         if ((alignment & (alignment - 1)) != 0)
  184                 panic("contigmalloc1: alignment must be a power of 2");
  185         if ((boundary & (boundary - 1)) != 0)
  186                 panic("contigmalloc1: boundary must be a power of 2");
  187 
  188         start = 0;
  189         for (pass = 2; pass >= 0; pass--) {
  190                 vm_page_lock_queues();
  191 again0:
  192                 mtx_lock_spin(&vm_page_queue_free_mtx);
  193 again:
  194                 /*
  195                  * Find first page in array that is free, within range,
  196                  * aligned, and such that the boundary won't be crossed.
  197                  */
  198                 for (i = start; i < cnt.v_page_count; i++) {
  199                         phys = VM_PAGE_TO_PHYS(&pga[i]);
  200                         pqtype = pga[i].queue - pga[i].pc;
  201                         if (((pqtype == PQ_FREE) || (pqtype == PQ_CACHE)) &&
  202                             (phys >= low) && (phys < high) &&
  203                             ((phys & (alignment - 1)) == 0) &&
  204                             (((phys ^ (phys + size - 1)) & ~(boundary - 1)) == 0))
  205                                 break;
  206                 }
  207 
  208                 /*
  209                  * If the above failed or we will exceed the upper bound, fail.
  210                  */
  211                 if ((i == cnt.v_page_count) ||
  212                         ((VM_PAGE_TO_PHYS(&pga[i]) + size) > high)) {
  213                         mtx_unlock_spin(&vm_page_queue_free_mtx);
  214                         /*
  215                          * Instead of racing to empty the inactive/active
  216                          * queues, give up, even with more left to free,
  217                          * if we try more than the initial amount of pages.
  218                          *
  219                          * There's no point attempting this on the last pass.
  220                          */
  221                         if (pass > 0) {
  222                                 inactl = actl = 0;
  223                                 inactmax = vm_page_queues[PQ_INACTIVE].lcnt;
  224                                 actmax = vm_page_queues[PQ_ACTIVE].lcnt;
  225 again1:
  226                                 if (inactl < inactmax &&
  227                                     vm_contig_launder(PQ_INACTIVE)) {
  228                                         inactl++;
  229                                         goto again1;
  230                                 }
  231                                 if (actl < actmax &&
  232                                     vm_contig_launder(PQ_ACTIVE)) {
  233                                         actl++;
  234                                         goto again1;
  235                                 }
  236                         }
  237                         vm_page_unlock_queues();
  238                         continue;
  239                 }
  240                 start = i;
  241 
  242                 /*
  243                  * Check successive pages for contiguous and free.
  244                  */
  245                 for (i = start + 1; i < (start + size / PAGE_SIZE); i++) {
  246                         pqtype = pga[i].queue - pga[i].pc;
  247                         if ((VM_PAGE_TO_PHYS(&pga[i]) !=
  248                             (VM_PAGE_TO_PHYS(&pga[i - 1]) + PAGE_SIZE)) ||
  249                             ((pqtype != PQ_FREE) && (pqtype != PQ_CACHE))) {
  250                                 start++;
  251                                 goto again;
  252                         }
  253                 }
  254                 mtx_unlock_spin(&vm_page_queue_free_mtx);
  255                 for (i = start; i < (start + size / PAGE_SIZE); i++) {
  256                         vm_page_t m = &pga[i];
  257 
  258                         if ((m->queue - m->pc) == PQ_CACHE) {
  259                                 if (m->hold_count != 0) {
  260                                         start++;
  261                                         goto again0;
  262                                 }
  263                                 object = m->object;
  264                                 if (!VM_OBJECT_TRYLOCK(object)) {
  265                                         start++;
  266                                         goto again0;
  267                                 }
  268                                 if ((m->flags & PG_BUSY) || m->busy != 0) {
  269                                         VM_OBJECT_UNLOCK(object);
  270                                         start++;
  271                                         goto again0;
  272                                 }
  273                                 vm_page_free(m);
  274                                 VM_OBJECT_UNLOCK(object);
  275                         }
  276                 }
  277                 mtx_lock_spin(&vm_page_queue_free_mtx);
  278                 for (i = start; i < (start + size / PAGE_SIZE); i++) {
  279                         pqtype = pga[i].queue - pga[i].pc;
  280                         if (pqtype != PQ_FREE) {
  281                                 start++;
  282                                 goto again;
  283                         }
  284                 }
  285                 for (i = start; i < (start + size / PAGE_SIZE); i++) {
  286                         vm_page_t m = &pga[i];
  287                         vm_pageq_remove_nowakeup(m);
  288                         m->valid = VM_PAGE_BITS_ALL;
  289                         if (m->flags & PG_ZERO)
  290                                 vm_page_zero_count--;
  291                         /* Don't clear the PG_ZERO flag, we'll need it later. */
  292                         m->flags = PG_UNMANAGED | (m->flags & PG_ZERO);
  293                         KASSERT(m->dirty == 0,
  294                             ("contigmalloc1: page %p was dirty", m));
  295                         m->wire_count = 0;
  296                         m->busy = 0;
  297                 }
  298                 mtx_unlock_spin(&vm_page_queue_free_mtx);
  299                 vm_page_unlock_queues();
  300                 /*
  301                  * We've found a contiguous chunk that meets are requirements.
  302                  * Allocate kernel VM, unfree and assign the physical pages to
  303                  * it and return kernel VM pointer.
  304                  */
  305                 vm_map_lock(map);
  306                 if (vm_map_findspace(map, vm_map_min(map), size, &addr) !=
  307                     KERN_SUCCESS) {
  308                         /*
  309                          * XXX We almost never run out of kernel virtual
  310                          * space, so we don't make the allocated memory
  311                          * above available.
  312                          */
  313                         vm_map_unlock(map);
  314                         return (NULL);
  315                 }
  316                 vm_object_reference(kernel_object);
  317                 vm_map_insert(map, kernel_object, addr - VM_MIN_KERNEL_ADDRESS,
  318                     addr, addr + size, VM_PROT_ALL, VM_PROT_ALL, 0);
  319                 vm_map_unlock(map);
  320 
  321                 tmp_addr = addr;
  322                 VM_OBJECT_LOCK(kernel_object);
  323                 for (i = start; i < (start + size / PAGE_SIZE); i++) {
  324                         vm_page_t m = &pga[i];
  325                         vm_page_insert(m, kernel_object,
  326                                 OFF_TO_IDX(tmp_addr - VM_MIN_KERNEL_ADDRESS));
  327                         if ((flags & M_ZERO) && !(m->flags & PG_ZERO))
  328                                 pmap_zero_page(m);
  329                         tmp_addr += PAGE_SIZE;
  330                 }
  331                 VM_OBJECT_UNLOCK(kernel_object);
  332                 vm_map_wire(map, addr, addr + size,
  333                     VM_MAP_WIRE_SYSTEM|VM_MAP_WIRE_NOHOLES);
  334 
  335                 return ((void *)addr);
  336         }
  337         return (NULL);
  338 }
  339 
  340 static void
  341 vm_page_release_contigl(vm_page_t m, vm_pindex_t count)
  342 {
  343         while (count--) {
  344                 vm_page_free_toq(m);
  345                 m++;
  346         }
  347 }
  348 
  349 void
  350 vm_page_release_contig(vm_page_t m, vm_pindex_t count)
  351 {
  352         vm_page_lock_queues();
  353         vm_page_release_contigl(m, count);
  354         vm_page_unlock_queues();
  355 }
  356 
  357 static int
  358 vm_contig_unqueue_free(vm_page_t m)
  359 {
  360         int error = 0;
  361 
  362         mtx_lock_spin(&vm_page_queue_free_mtx);
  363         if ((m->queue - m->pc) == PQ_FREE)
  364                 vm_pageq_remove_nowakeup(m);
  365         else
  366                 error = EAGAIN;
  367         mtx_unlock_spin(&vm_page_queue_free_mtx);
  368         if (error)
  369                 return (error);
  370         m->valid = VM_PAGE_BITS_ALL;
  371         if (m->flags & PG_ZERO)
  372                 vm_page_zero_count--;
  373         /* Don't clear the PG_ZERO flag; we'll need it later. */
  374         m->flags = PG_UNMANAGED | (m->flags & PG_ZERO);
  375         KASSERT(m->dirty == 0,
  376             ("contigmalloc2: page %p was dirty", m));
  377         m->wire_count = 0;
  378         m->busy = 0;
  379         return (error);
  380 }
  381 
  382 vm_page_t
  383 vm_page_alloc_contig(vm_pindex_t npages, vm_paddr_t low, vm_paddr_t high,
  384             vm_offset_t alignment, vm_offset_t boundary)
  385 {
  386         vm_object_t object;
  387         vm_offset_t size;
  388         vm_paddr_t phys;
  389         vm_page_t pga = vm_page_array;
  390         int i, pass, pqtype, start;
  391 
  392         size = npages << PAGE_SHIFT;
  393         if (size == 0)
  394                 panic("vm_page_alloc_contig: size must not be 0");
  395         if ((alignment & (alignment - 1)) != 0)
  396                 panic("vm_page_alloc_contig: alignment must be a power of 2");
  397         if ((boundary & (boundary - 1)) != 0)
  398                 panic("vm_page_alloc_contig: boundary must be a power of 2");
  399 
  400         for (pass = 0; pass < 2; pass++) {
  401                 start = vm_page_array_size - npages + 1;
  402                 vm_page_lock_queues();
  403 retry:
  404                 start--;
  405                 /*
  406                  * Find last page in array that is free, within range,
  407                  * aligned, and such that the boundary won't be crossed.
  408                  */
  409                 for (i = start; i >= 0; i--) {
  410                         phys = VM_PAGE_TO_PHYS(&pga[i]);
  411                         pqtype = pga[i].queue - pga[i].pc;
  412                         if (pass == 0) {
  413                                 if (pqtype != PQ_FREE && pqtype != PQ_CACHE)
  414                                         continue;
  415                         } else if (pqtype != PQ_FREE && pqtype != PQ_CACHE &&
  416                                     pga[i].queue != PQ_ACTIVE &&
  417                                     pga[i].queue != PQ_INACTIVE)
  418                                 continue;
  419                         if (phys >= low && phys + size <= high &&
  420                             ((phys & (alignment - 1)) == 0) &&
  421                             ((phys ^ (phys + size - 1)) & ~(boundary - 1)) == 0)
  422                                 break;
  423                 }
  424                 /* There are no candidates at all. */
  425                 if (i == -1) {
  426                         vm_page_unlock_queues();
  427                         continue;
  428                 }
  429                 start = i;
  430                 /*
  431                  * Check successive pages for contiguous and free.
  432                  */
  433                 for (i = start + npages - 1; i > start; i--) {
  434                         pqtype = pga[i].queue - pga[i].pc;
  435                         if (VM_PAGE_TO_PHYS(&pga[i]) !=
  436                             VM_PAGE_TO_PHYS(&pga[i - 1]) + PAGE_SIZE) {
  437                                 start = i - npages + 1;
  438                                 goto retry;
  439                         }
  440                         if (pass == 0) {
  441                                 if (pqtype != PQ_FREE && pqtype != PQ_CACHE) {
  442                                         start = i - npages + 1;
  443                                         goto retry;
  444                                 }
  445                         } else if (pqtype != PQ_FREE && pqtype != PQ_CACHE &&
  446                                     pga[i].queue != PQ_ACTIVE &&
  447                                     pga[i].queue != PQ_INACTIVE) {
  448                                 start = i - npages + 1;
  449                                 goto retry;
  450                         }
  451                 }
  452                 for (i = start + npages - 1; i >= start; i--) {
  453                         vm_page_t m = &pga[i];
  454 
  455 retry_page:
  456                         pqtype = m->queue - m->pc;
  457                         if (pass != 0 && pqtype != PQ_FREE &&
  458                             pqtype != PQ_CACHE) {
  459                                 switch (m->queue) {
  460                                 case PQ_ACTIVE:
  461                                 case PQ_INACTIVE:
  462                                         if (vm_contig_launder_page(m) != 0)
  463                                                 goto cleanup_freed;
  464                                         pqtype = m->queue - m->pc;
  465                                         if (pqtype == PQ_FREE ||
  466                                             pqtype == PQ_CACHE)
  467                                                 break;
  468                                 default:
  469 cleanup_freed:
  470                                         vm_page_release_contigl(&pga[i + 1],
  471                                             start + npages - 1 - i);
  472                                         start = i - npages + 1;
  473                                         goto retry;
  474                                 }
  475                         }
  476                         if (pqtype == PQ_CACHE) {
  477                                 if (m->hold_count != 0) {
  478                                         start = i - npages + 1;
  479                                         goto retry;
  480                                 }
  481                                 object = m->object;
  482                                 if (!VM_OBJECT_TRYLOCK(object)) {
  483                                         start = i - npages + 1;
  484                                         goto retry;
  485                                 }
  486                                 if ((m->flags & PG_BUSY) || m->busy != 0) {
  487                                         VM_OBJECT_UNLOCK(object);
  488                                         start = i - npages + 1;
  489                                         goto retry;
  490                                 }
  491                                 vm_page_free(m);
  492                                 VM_OBJECT_UNLOCK(object);
  493                         }
  494                         /*
  495                          * There is no good API for freeing a page
  496                          * directly to PQ_NONE on our behalf, so spin.
  497                          */
  498                         if (vm_contig_unqueue_free(m) != 0)
  499                                 goto retry_page;
  500                 }
  501                 vm_page_unlock_queues();
  502                 /*
  503                  * We've found a contiguous chunk that meets are requirements.
  504                  */
  505                 return (&pga[start]);
  506         }
  507         return (NULL);
  508 }
  509 
  510 static void *
  511 contigmalloc2(vm_page_t m, vm_pindex_t npages, int flags)
  512 {
  513         vm_object_t object = kernel_object;
  514         vm_map_t map = kernel_map;
  515         vm_offset_t addr, tmp_addr;
  516         vm_pindex_t i;
  517  
  518         /*
  519          * Allocate kernel VM, unfree and assign the physical pages to
  520          * it and return kernel VM pointer.
  521          */
  522         vm_map_lock(map);
  523         if (vm_map_findspace(map, vm_map_min(map), npages << PAGE_SHIFT, &addr)
  524             != KERN_SUCCESS) {
  525                 vm_map_unlock(map);
  526                 return (NULL);
  527         }
  528         vm_object_reference(object);
  529         vm_map_insert(map, object, addr - VM_MIN_KERNEL_ADDRESS,
  530             addr, addr + (npages << PAGE_SHIFT), VM_PROT_ALL, VM_PROT_ALL, 0);
  531         vm_map_unlock(map);
  532         tmp_addr = addr;
  533         VM_OBJECT_LOCK(object);
  534         for (i = 0; i < npages; i++) {
  535                 vm_page_insert(&m[i], object,
  536                     OFF_TO_IDX(tmp_addr - VM_MIN_KERNEL_ADDRESS));
  537                 if ((flags & M_ZERO) && !(m->flags & PG_ZERO))
  538                         pmap_zero_page(&m[i]);
  539                 tmp_addr += PAGE_SIZE;
  540         }
  541         VM_OBJECT_UNLOCK(object);
  542         vm_map_wire(map, addr, addr + (npages << PAGE_SHIFT),
  543             VM_MAP_WIRE_SYSTEM | VM_MAP_WIRE_NOHOLES);
  544         return ((void *)addr);
  545 }
  546 
  547 static int vm_old_contigmalloc = 0;
  548 SYSCTL_INT(_vm, OID_AUTO, old_contigmalloc,
  549     CTLFLAG_RW, &vm_old_contigmalloc, 0, "Use the old contigmalloc algorithm");
  550 TUNABLE_INT("vm.old_contigmalloc", &vm_old_contigmalloc);
  551 
  552 void *
  553 contigmalloc(
  554         unsigned long size,     /* should be size_t here and for malloc() */
  555         struct malloc_type *type,
  556         int flags,
  557         vm_paddr_t low,
  558         vm_paddr_t high,
  559         unsigned long alignment,
  560         unsigned long boundary)
  561 {
  562         void * ret;
  563         vm_page_t pages;
  564         vm_pindex_t npgs;
  565 
  566         npgs = round_page(size) >> PAGE_SHIFT;
  567         mtx_lock(&Giant);
  568         if (vm_old_contigmalloc) {
  569                 ret = contigmalloc1(size, type, flags, low, high, alignment,
  570                     boundary, kernel_map);
  571         } else {
  572                 pages = vm_page_alloc_contig(npgs, low, high,
  573                     alignment, boundary);
  574                 if (pages == NULL) {
  575                         ret = NULL;
  576                 } else {
  577                         ret = contigmalloc2(pages, npgs, flags);
  578                         if (ret == NULL)
  579                                 vm_page_release_contig(pages, npgs);
  580                 }
  581                 
  582         }
  583         mtx_unlock(&Giant);
  584         malloc_type_allocated(type, ret == NULL ? 0 : npgs << PAGE_SHIFT);
  585         return (ret);
  586 }
  587 
  588 void
  589 contigfree(void *addr, unsigned long size, struct malloc_type *type)
  590 {
  591         vm_pindex_t npgs;
  592 
  593         npgs = round_page(size) >> PAGE_SHIFT;
  594         kmem_free(kernel_map, (vm_offset_t)addr, size);
  595         malloc_type_freed(type, npgs << PAGE_SHIFT);
  596 }

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