1 /* 2 * (MPSAFE) 3 * 4 * Copyright (c) 2000 Peter Wemm 5 * 6 * Redistribution and use in source and binary forms, with or without 7 * modification, are permitted provided that the following conditions 8 * are met: 9 * 1. Redistributions of source code must retain the above copyright 10 * notice, this list of conditions and the following disclaimer. 11 * 2. Redistributions in binary form must reproduce the above copyright 12 * notice, this list of conditions and the following disclaimer in the 13 * documentation and/or other materials provided with the distribution. 14 * 15 * THIS SOFTWARE IS PROVIDED BY THE AUTHORS AND CONTRIBUTORS ``AS IS'' AND 16 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 17 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 18 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHORS OR CONTRIBUTORS BE LIABLE 19 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 20 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 21 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 22 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 23 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 24 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 25 * SUCH DAMAGE. 26 * 27 * $FreeBSD: src/sys/vm/phys_pager.c,v 1.3.2.3 2000/12/17 02:05:41 alfred Exp $ 28 */ 29 #include <sys/param.h> 30 #include <sys/systm.h> 31 #include <sys/linker_set.h> 32 #include <sys/conf.h> 33 #include <sys/mman.h> 34 #include <sys/sysctl.h> 35 36 #include <vm/vm.h> 37 #include <vm/vm_object.h> 38 #include <vm/vm_page.h> 39 #include <vm/vm_pager.h> 40 #include <vm/vm_zone.h> 41 42 #include <vm/vm_page2.h> 43 44 static pgo_dealloc_t phys_pager_dealloc; 45 static pgo_getpage_t phys_pager_getpage; 46 static pgo_putpages_t phys_pager_putpages; 47 static pgo_haspage_t phys_pager_haspage; 48 49 struct pagerops physpagerops = { 50 .pgo_dealloc = phys_pager_dealloc, 51 .pgo_getpage = phys_pager_getpage, 52 .pgo_putpages = phys_pager_putpages, 53 .pgo_haspage = phys_pager_haspage 54 }; 55 56 /* 57 * No requirements. 58 */ 59 vm_object_t 60 phys_pager_alloc(void *handle, off_t size, vm_prot_t prot, off_t foff) 61 { 62 vm_object_t object; 63 64 /* 65 * Offset should be page aligned. 66 */ 67 if (foff & PAGE_MASK) 68 return (NULL); 69 70 size = round_page64(size); 71 72 KKASSERT(handle == NULL); 73 object = vm_object_allocate(OBJT_PHYS, OFF_TO_IDX(foff + size)); 74 75 return (object); 76 } 77 78 /* 79 * No requirements. 80 */ 81 static void 82 phys_pager_dealloc(vm_object_t object) 83 { 84 KKASSERT(object->handle == NULL); 85 KKASSERT(object->swblock_count == 0); 86 } 87 88 /* 89 * No requirements. 90 */ 91 static int 92 phys_pager_getpage(vm_object_t object, vm_pindex_t pindex, 93 vm_page_t *mpp, int seqaccess) 94 { 95 vm_page_t m = *mpp; 96 97 vm_page_zero_fill(m); 98 /* Switch off pv_entries */ 99 vm_page_flag_set(m, PG_UNQUEUED); 100 m->valid = VM_PAGE_BITS_ALL; 101 m->dirty = VM_PAGE_BITS_ALL; 102 103 return (VM_PAGER_OK); 104 } 105 106 /* 107 * No requirements. 108 */ 109 static void 110 phys_pager_putpages(vm_object_t object, vm_page_t *m, int count, 111 int flags, int *rtvals) 112 { 113 114 panic("phys_pager_putpage called"); 115 } 116 117 /* 118 * Implement a pretty aggressive clustered getpages strategy. Hint that 119 * everything in an entire 4MB window should be prefaulted at once. 120 * 121 * XXX 4MB (1024 slots per page table page) is convenient for x86, 122 * but may not be for other arches. 123 */ 124 #ifndef PHYSCLUSTER 125 #define PHYSCLUSTER 1024 126 #endif 127 128 /* 129 * No requirements. 130 */ 131 static boolean_t 132 phys_pager_haspage(vm_object_t object, vm_pindex_t pindex) 133 { 134 return (TRUE); 135 } 136