1 /* 2 * Copyright (c) 1990 University of Utah. 3 * Copyright (c) 1991 The Regents of the University of California. 4 * 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 * $Id: vm_pager.h,v 1.3 93/11/28 19:25:41 bill Exp $ 39 */ 40 41 /* 42 * Pager routine interface definition. 43 * For BSD we use a cleaner version of the internal pager interface. 44 */ 45 46 #ifndef _VM_PAGER_ 47 #define _VM_PAGER_ 48 49 struct pager_struct { 50 queue_head_t pg_list; /* links for list management */ 51 caddr_t pg_handle; /* external handle (vp, dev, fp) */ 52 int pg_type; /* type of pager */ 53 struct pagerops *pg_ops; /* pager operations */ 54 /* vm_map_t pg_shmap; /* shared map (if shared) */ 55 caddr_t pg_data; /* private pager data */ 56 }; 57 typedef struct pager_struct *vm_pager_t; 58 59 /* pager types */ 60 #define PG_DFLT -1 61 #define PG_SWAP 0 62 #define PG_VNODE 1 63 #define PG_DEVICE 2 64 65 struct pagerops { 66 void (*pgo_init)(); /* initialize pager */ 67 vm_pager_t (*pgo_alloc)(); /* allocate pager */ 68 void (*pgo_dealloc)(); /* disassociate */ 69 int (*pgo_getpage)(); /* get (read) page */ 70 int (*pgo_putpage)(); /* put (write) page */ 71 boolean_t (*pgo_haspage)(); /* does pager have page? */ 72 }; 73 74 /* 75 * get/put return values 76 * OK operation was successful 77 * BAD specified data was out of the accepted range 78 * FAIL specified data was in range, but doesn't exist 79 * PEND operations was initiated but not completed 80 */ 81 #define VM_PAGER_OK 0 82 #define VM_PAGER_BAD 1 83 #define VM_PAGER_FAIL 2 84 #define VM_PAGER_PEND 3 85 86 #define VM_PAGER_ALLOC(h, s, p) (*(pg)->pg_ops->pgo_alloc)(h, s, p) 87 #define VM_PAGER_DEALLOC(pg) (*(pg)->pg_ops->pgo_dealloc)(pg) 88 #define VM_PAGER_GET(pg, m, s) (*(pg)->pg_ops->pgo_getpage)(pg, m, s) 89 #define VM_PAGER_PUT(pg, m, s) (*(pg)->pg_ops->pgo_putpage)(pg, m, s) 90 #define VM_PAGER_HASPAGE(pg, o) (*(pg)->pg_ops->pgo_haspage)(pg, o) 91 92 #ifdef KERNEL 93 vm_pager_t 94 vm_pager_allocate(int type, caddr_t handle, vm_size_t size, 95 vm_prot_t prot); 96 void vm_pager_deallocate(vm_pager_t pager); 97 int vm_pager_get(vm_pager_t pager, vm_page_t m, boolean_t sync); 98 int vm_pager_put(vm_pager_t pager, vm_page_t m, boolean_t sync); 99 boolean_t 100 vm_pager_has_page(vm_pager_t pager, vm_offset_t offset); 101 102 vm_offset_t 103 vm_pager_map_page(vm_page_t m); 104 void vm_pager_unmap_page(vm_offset_t kva); 105 vm_pager_t 106 vm_pager_lookup(queue_head_t *list, caddr_t handle); 107 void vm_pager_sync(); 108 int pager_cache(vm_object_t object, boolean_t should_cache); 109 110 extern struct pagerops *dfltpagerops; 111 #endif 112 113 #endif /* _VM_PAGER_ */ 114