1 /* 2 * Copyright (c) 1990 University of Utah. 3 * Copyright (c) 1991, 1993 4 * The Regents of the University of California. All rights reserved. 5 * 6 * This code is derived from software contributed to Berkeley by 7 * the Systems Programming Group of the University of Utah Computer 8 * Science Department. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 3. All advertising materials mentioning features or use of this software 19 * must display the following acknowledgement: 20 * This product includes software developed by the University of 21 * California, Berkeley and its contributors. 22 * 4. Neither the name of the University nor the names of its contributors 23 * may be used to endorse or promote products derived from this software 24 * without specific prior written permission. 25 * 26 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 27 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 28 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 29 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 30 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 31 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 32 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 33 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 34 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 35 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 36 * SUCH DAMAGE. 37 * 38 * @(#)vm_pager.h 8.4 (Berkeley) 1/12/94 39 * $FreeBSD: src/sys/vm/vm_pager.h,v 1.24.2.2 2002/12/31 09:34:51 dillon Exp $ 40 * $DragonFly: src/sys/vm/vm_pager.h,v 1.9 2006/12/28 21:24:02 dillon Exp $ 41 */ 42 43 /* 44 * Pager routine interface definition. 45 */ 46 47 #ifndef _VM_VM_PAGER_H_ 48 #define _VM_VM_PAGER_H_ 49 50 #ifndef _SYS_QUEUE_H_ 51 #include <sys/queue.h> 52 #endif 53 #ifndef _VM_VM_PAGE_H_ 54 #include <vm/vm_page.h> 55 #endif 56 #ifndef _VM_VM_OBJECT_H_ 57 #include <vm/vm_object.h> 58 #endif 59 60 struct buf; 61 struct bio; 62 63 struct pagerops { 64 void (*pgo_dealloc) (vm_object_t); 65 int (*pgo_getpage) (vm_object_t, vm_page_t *, int); 66 void (*pgo_putpages) (vm_object_t, vm_page_t *, int, int, int *); 67 boolean_t (*pgo_haspage) (vm_object_t, vm_pindex_t); 68 }; 69 70 /* 71 * get/put return values 72 * OK operation was successful 73 * BAD specified data was out of the accepted range 74 * FAIL specified data was in range, but doesn't exist 75 * PEND operations was initiated but not completed 76 * ERROR error while accessing data that is in range and exists 77 * AGAIN temporary resource shortage prevented operation from happening 78 */ 79 #define VM_PAGER_OK 0 80 #define VM_PAGER_BAD 1 81 #define VM_PAGER_FAIL 2 82 #define VM_PAGER_PEND 3 83 #define VM_PAGER_ERROR 4 84 #define VM_PAGER_AGAIN 5 85 86 #define VM_PAGER_PUT_SYNC 0x0001 87 #define VM_PAGER_PUT_INVAL 0x0002 88 #define VM_PAGER_IGNORE_CLEANCHK 0x0004 89 #define VM_PAGER_CLUSTER_OK 0x0008 90 91 #ifdef _KERNEL 92 93 #ifdef MALLOC_DECLARE 94 MALLOC_DECLARE(M_VMPGDATA); 95 #endif 96 97 struct vnode; 98 99 extern struct vm_map pager_map; 100 extern int pager_map_size; 101 extern struct pagerops *pagertab[]; 102 103 vm_object_t default_pager_alloc(void *, off_t, vm_prot_t, off_t); 104 vm_object_t dev_pager_alloc(void *, off_t, vm_prot_t, off_t); 105 vm_object_t phys_pager_alloc(void *, off_t, vm_prot_t, off_t); 106 vm_object_t swap_pager_alloc(void *, off_t, vm_prot_t, off_t); 107 vm_object_t vnode_pager_alloc (void *, off_t, vm_prot_t, off_t, int, int); 108 vm_object_t vnode_pager_reference (struct vnode *); 109 110 void vm_pager_bufferinit (void); 111 void vm_pager_deallocate (vm_object_t); 112 static __inline int vm_pager_get_page (vm_object_t, vm_page_t *, int); 113 static __inline boolean_t vm_pager_has_page (vm_object_t, vm_pindex_t); 114 void vm_pager_sync (void); 115 struct buf *getchainbuf(struct buf *bp, struct vnode *vp, int flags); 116 void flushchainbuf(struct buf *nbp); 117 void waitchainbuf(struct buf *bp, int count, int done); 118 void autochaindone(struct buf *bp); 119 void swap_pager_strategy(vm_object_t object, struct bio *bio); 120 void swap_pager_unswapped (vm_page_t m); 121 122 /* 123 * vm_page_get_pages: 124 * 125 * Retrieve the contents of the page from the object pager. Note that the 126 * object pager might replace the page. 127 * 128 * If the pagein was successful, we must fully validate it so it can be 129 * memory mapped. 130 */ 131 132 static __inline int 133 vm_pager_get_page(vm_object_t object, vm_page_t *m, int seqaccess) 134 { 135 int r; 136 137 r = (*pagertab[object->type]->pgo_getpage)(object, m, seqaccess); 138 if (r == VM_PAGER_OK && (*m)->valid != VM_PAGE_BITS_ALL) { 139 vm_page_zero_invalid(*m, TRUE); 140 } 141 return(r); 142 } 143 144 static __inline void 145 vm_pager_put_pages( 146 vm_object_t object, 147 vm_page_t *m, 148 int count, 149 int flags, 150 int *rtvals 151 ) { 152 (*pagertab[object->type]->pgo_putpages) 153 (object, m, count, flags, rtvals); 154 } 155 156 /* 157 * vm_pager_haspage 158 * 159 * Check to see if an object's pager has the requested page. The 160 * object's pager will also set before and after to give the caller 161 * some idea of the number of pages before and after the requested 162 * page can be I/O'd efficiently. 163 * 164 * This routine does not have to be called at any particular spl. 165 */ 166 167 static __inline boolean_t 168 vm_pager_has_page(vm_object_t object, vm_pindex_t offset) 169 { 170 return ((*pagertab[object->type]->pgo_haspage)(object, offset)); 171 } 172 173 #endif 174 175 #endif /* _VM_VM_PAGER_H_ */ 176