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 * 4. Neither the name of the University nor the names of its contributors 19 * may be used to endorse or promote products derived from this software 20 * without specific prior written permission. 21 * 22 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 23 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 24 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 25 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 26 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 27 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 28 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 29 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 30 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 31 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 32 * SUCH DAMAGE. 33 * 34 * @(#)vm_pager.h 8.4 (Berkeley) 1/12/94 35 * $FreeBSD$ 36 */ 37 38/* 39 * Pager routine interface definition. 40 */ 41 42#ifndef _VM_PAGER_ 43#define _VM_PAGER_ 44 45#include <sys/queue.h> 46 47TAILQ_HEAD(pagerlst, vm_object); 48 49typedef void pgo_init_t(void); 50typedef vm_object_t pgo_alloc_t(void *, vm_ooffset_t, vm_prot_t, vm_ooffset_t, 51 struct ucred *); 52typedef void pgo_dealloc_t(vm_object_t); 53typedef int pgo_getpages_t(vm_object_t, vm_page_t *, int, int *, int *); 54typedef void pgo_getpages_iodone_t(void *, vm_page_t *, int, int); 55typedef int pgo_getpages_async_t(vm_object_t, vm_page_t *, int, int *, int *, 56 pgo_getpages_iodone_t, void *); 57typedef void pgo_putpages_t(vm_object_t, vm_page_t *, int, int, int *); 58typedef boolean_t pgo_haspage_t(vm_object_t, vm_pindex_t, int *, int *); 59typedef void pgo_pageunswapped_t(vm_page_t); 60 61struct pagerops { 62 pgo_init_t *pgo_init; /* Initialize pager. */ 63 pgo_alloc_t *pgo_alloc; /* Allocate pager. */ 64 pgo_dealloc_t *pgo_dealloc; /* Disassociate. */ 65 pgo_getpages_t *pgo_getpages; /* Get (read) page. */ 66 pgo_getpages_async_t *pgo_getpages_async; /* Get page asyncly. */ 67 pgo_putpages_t *pgo_putpages; /* Put (write) page. */ 68 pgo_haspage_t *pgo_haspage; /* Query page. */ 69 pgo_pageunswapped_t *pgo_pageunswapped; 70}; 71 72extern struct pagerops defaultpagerops; 73extern struct pagerops swappagerops; 74extern struct pagerops vnodepagerops; 75extern struct pagerops devicepagerops; 76extern struct pagerops physpagerops; 77extern struct pagerops sgpagerops; 78extern struct pagerops mgtdevicepagerops; 79 80/* 81 * get/put return values 82 * OK operation was successful 83 * BAD specified data was out of the accepted range 84 * FAIL specified data was in range, but doesn't exist 85 * PEND operations was initiated but not completed 86 * ERROR error while accessing data that is in range and exists 87 * AGAIN temporary resource shortage prevented operation from happening 88 */ 89#define VM_PAGER_OK 0 90#define VM_PAGER_BAD 1 91#define VM_PAGER_FAIL 2 92#define VM_PAGER_PEND 3 93#define VM_PAGER_ERROR 4 94#define VM_PAGER_AGAIN 5 95 96#define VM_PAGER_PUT_SYNC 0x0001 97#define VM_PAGER_PUT_INVAL 0x0002 98#define VM_PAGER_CLUSTER_OK 0x0008 99 100#ifdef _KERNEL 101 102extern struct pagerops *pagertab[]; 103extern struct mtx_padalign pbuf_mtx; 104 105vm_object_t vm_pager_allocate(objtype_t, void *, vm_ooffset_t, vm_prot_t, 106 vm_ooffset_t, struct ucred *); 107void vm_pager_bufferinit(void); 108void vm_pager_deallocate(vm_object_t); 109int vm_pager_get_pages(vm_object_t, vm_page_t *, int, int *, int *); 110int vm_pager_get_pages_async(vm_object_t, vm_page_t *, int, int *, int *, 111 pgo_getpages_iodone_t, void *); 112static __inline boolean_t vm_pager_has_page(vm_object_t, vm_pindex_t, int *, int *); 113void vm_pager_init(void); 114vm_object_t vm_pager_object_lookup(struct pagerlst *, void *); 115 116static __inline void 117vm_pager_put_pages( 118 vm_object_t object, 119 vm_page_t *m, 120 int count, 121 int flags, 122 int *rtvals 123) { 124 125 VM_OBJECT_ASSERT_WLOCKED(object); 126 (*pagertab[object->type]->pgo_putpages) 127 (object, m, count, flags, rtvals); 128} 129 130/* 131 * vm_pager_haspage 132 * 133 * Check to see if an object's pager has the requested page. The 134 * object's pager will also set before and after to give the caller 135 * some idea of the number of pages before and after the requested 136 * page can be I/O'd efficiently. 137 * 138 * The object must be locked. 139 */ 140static __inline boolean_t 141vm_pager_has_page( 142 vm_object_t object, 143 vm_pindex_t offset, 144 int *before, 145 int *after 146) { 147 boolean_t ret; 148 149 VM_OBJECT_ASSERT_WLOCKED(object); 150 ret = (*pagertab[object->type]->pgo_haspage) 151 (object, offset, before, after); 152 return (ret); 153} 154 155/* 156 * vm_pager_page_unswapped 157 * 158 * Destroy swap associated with the page. 159 * 160 * The object containing the page must be locked. 161 * This function may not block. 162 * 163 * XXX: A much better name would be "vm_pager_page_dirtied()" 164 * XXX: It is not obvious if this could be profitably used by any 165 * XXX: pagers besides the swap_pager or if it should even be a 166 * XXX: generic pager_op in the first place. 167 */ 168static __inline void 169vm_pager_page_unswapped(vm_page_t m) 170{ 171 172 VM_OBJECT_ASSERT_LOCKED(m->object); 173 if (pagertab[m->object->type]->pgo_pageunswapped) 174 (*pagertab[m->object->type]->pgo_pageunswapped)(m); 175} 176 177struct cdev_pager_ops { 178 int (*cdev_pg_fault)(vm_object_t vm_obj, vm_ooffset_t offset, 179 int prot, vm_page_t *mres); 180 int (*cdev_pg_ctor)(void *handle, vm_ooffset_t size, vm_prot_t prot, 181 vm_ooffset_t foff, struct ucred *cred, u_short *color); 182 void (*cdev_pg_dtor)(void *handle); 183}; 184 185vm_object_t cdev_pager_allocate(void *handle, enum obj_type tp, 186 struct cdev_pager_ops *ops, vm_ooffset_t size, vm_prot_t prot, 187 vm_ooffset_t foff, struct ucred *cred); 188vm_object_t cdev_pager_lookup(void *handle); 189void cdev_pager_free_page(vm_object_t object, vm_page_t m); 190 191#endif /* _KERNEL */ 192#endif /* _VM_PAGER_ */ 193