1 /*- 2 * SPDX-License-Identifier: BSD-3-Clause 3 * 4 * Copyright (c) 1990 University of Utah. 5 * Copyright (c) 1991, 1993 6 * The Regents of the University of California. All rights reserved. 7 * 8 * This code is derived from software contributed to Berkeley by 9 * the Systems Programming Group of the University of Utah Computer 10 * Science Department. 11 * 12 * Redistribution and use in source and binary forms, with or without 13 * modification, are permitted provided that the following conditions 14 * are met: 15 * 1. Redistributions of source code must retain the above copyright 16 * notice, this list of conditions and the following disclaimer. 17 * 2. Redistributions in binary form must reproduce the above copyright 18 * notice, this list of conditions and the following disclaimer in the 19 * documentation and/or other materials provided with the distribution. 20 * 3. Neither the name of the University nor the names of its contributors 21 * may be used to endorse or promote products derived from this software 22 * without specific prior written permission. 23 * 24 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 25 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 26 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 27 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 28 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 29 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 30 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 31 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 32 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 33 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 34 * SUCH DAMAGE. 35 * 36 * @(#)vm_pager.h 8.4 (Berkeley) 1/12/94 37 * $FreeBSD$ 38 */ 39 40 /* 41 * Pager routine interface definition. 42 */ 43 44 #ifndef _VM_PAGER_ 45 #define _VM_PAGER_ 46 47 #include <sys/queue.h> 48 49 TAILQ_HEAD(pagerlst, vm_object); 50 51 typedef void pgo_init_t(void); 52 typedef vm_object_t pgo_alloc_t(void *, vm_ooffset_t, vm_prot_t, vm_ooffset_t, 53 struct ucred *); 54 typedef void pgo_dealloc_t(vm_object_t); 55 typedef int pgo_getpages_t(vm_object_t, vm_page_t *, int, int *, int *); 56 typedef void pgo_getpages_iodone_t(void *, vm_page_t *, int, int); 57 typedef int pgo_getpages_async_t(vm_object_t, vm_page_t *, int, int *, int *, 58 pgo_getpages_iodone_t, void *); 59 typedef void pgo_putpages_t(vm_object_t, vm_page_t *, int, int, int *); 60 typedef boolean_t pgo_haspage_t(vm_object_t, vm_pindex_t, int *, int *); 61 typedef int pgo_populate_t(vm_object_t, vm_pindex_t, int, vm_prot_t, 62 vm_pindex_t *, vm_pindex_t *); 63 typedef void pgo_pageunswapped_t(vm_page_t); 64 typedef void pgo_writecount_t(vm_object_t, vm_offset_t, vm_offset_t); 65 66 struct pagerops { 67 pgo_init_t *pgo_init; /* Initialize pager. */ 68 pgo_alloc_t *pgo_alloc; /* Allocate pager. */ 69 pgo_dealloc_t *pgo_dealloc; /* Disassociate. */ 70 pgo_getpages_t *pgo_getpages; /* Get (read) page. */ 71 pgo_getpages_async_t *pgo_getpages_async; /* Get page asyncly. */ 72 pgo_putpages_t *pgo_putpages; /* Put (write) page. */ 73 pgo_haspage_t *pgo_haspage; /* Query page. */ 74 pgo_populate_t *pgo_populate; /* Bulk spec pagein. */ 75 pgo_pageunswapped_t *pgo_pageunswapped; 76 /* Operations for specialized writecount handling */ 77 pgo_writecount_t *pgo_update_writecount; 78 pgo_writecount_t *pgo_release_writecount; 79 }; 80 81 extern struct pagerops defaultpagerops; 82 extern struct pagerops swappagerops; 83 extern struct pagerops vnodepagerops; 84 extern struct pagerops devicepagerops; 85 extern struct pagerops physpagerops; 86 extern struct pagerops sgpagerops; 87 extern struct pagerops mgtdevicepagerops; 88 89 /* 90 * get/put return values 91 * OK operation was successful 92 * BAD specified data was out of the accepted range 93 * FAIL specified data was in range, but doesn't exist 94 * PEND operations was initiated but not completed 95 * ERROR error while accessing data that is in range and exists 96 * AGAIN temporary resource shortage prevented operation from happening 97 */ 98 #define VM_PAGER_OK 0 99 #define VM_PAGER_BAD 1 100 #define VM_PAGER_FAIL 2 101 #define VM_PAGER_PEND 3 102 #define VM_PAGER_ERROR 4 103 #define VM_PAGER_AGAIN 5 104 105 #define VM_PAGER_PUT_SYNC 0x0001 106 #define VM_PAGER_PUT_INVAL 0x0002 107 #define VM_PAGER_PUT_NOREUSE 0x0004 108 #define VM_PAGER_CLUSTER_OK 0x0008 109 110 #ifdef _KERNEL 111 112 extern struct pagerops *pagertab[]; 113 extern struct mtx_padalign pbuf_mtx; 114 115 vm_object_t vm_pager_allocate(objtype_t, void *, vm_ooffset_t, vm_prot_t, 116 vm_ooffset_t, struct ucred *); 117 void vm_pager_bufferinit(void); 118 void vm_pager_deallocate(vm_object_t); 119 int vm_pager_get_pages(vm_object_t, vm_page_t *, int, int *, int *); 120 int vm_pager_get_pages_async(vm_object_t, vm_page_t *, int, int *, int *, 121 pgo_getpages_iodone_t, void *); 122 void vm_pager_init(void); 123 vm_object_t vm_pager_object_lookup(struct pagerlst *, void *); 124 125 static __inline void 126 vm_pager_put_pages( 127 vm_object_t object, 128 vm_page_t *m, 129 int count, 130 int flags, 131 int *rtvals 132 ) { 133 134 VM_OBJECT_ASSERT_WLOCKED(object); 135 (*pagertab[object->type]->pgo_putpages) 136 (object, m, count, flags, rtvals); 137 } 138 139 /* 140 * vm_pager_haspage 141 * 142 * Check to see if an object's pager has the requested page. The 143 * object's pager will also set before and after to give the caller 144 * some idea of the number of pages before and after the requested 145 * page can be I/O'd efficiently. 146 * 147 * The object must be locked. 148 */ 149 static __inline boolean_t 150 vm_pager_has_page( 151 vm_object_t object, 152 vm_pindex_t offset, 153 int *before, 154 int *after 155 ) { 156 boolean_t ret; 157 158 VM_OBJECT_ASSERT_LOCKED(object); 159 ret = (*pagertab[object->type]->pgo_haspage) 160 (object, offset, before, after); 161 return (ret); 162 } 163 164 static __inline int 165 vm_pager_populate(vm_object_t object, vm_pindex_t pidx, int fault_type, 166 vm_prot_t max_prot, vm_pindex_t *first, vm_pindex_t *last) 167 { 168 169 MPASS((object->flags & OBJ_POPULATE) != 0); 170 MPASS(pidx < object->size); 171 MPASS(blockcount_read(&object->paging_in_progress) > 0); 172 return ((*pagertab[object->type]->pgo_populate)(object, pidx, 173 fault_type, max_prot, first, last)); 174 } 175 176 177 /* 178 * vm_pager_page_unswapped 179 * 180 * Destroy swap associated with the page. 181 * 182 * XXX: A much better name would be "vm_pager_page_dirtied()" 183 * XXX: It is not obvious if this could be profitably used by any 184 * XXX: pagers besides the swap_pager or if it should even be a 185 * XXX: generic pager_op in the first place. 186 */ 187 static __inline void 188 vm_pager_page_unswapped(vm_page_t m) 189 { 190 191 if (pagertab[m->object->type]->pgo_pageunswapped) 192 (*pagertab[m->object->type]->pgo_pageunswapped)(m); 193 } 194 195 static __inline void 196 vm_pager_update_writecount(vm_object_t object, vm_offset_t start, 197 vm_offset_t end) 198 { 199 200 if (pagertab[object->type]->pgo_update_writecount) 201 pagertab[object->type]->pgo_update_writecount(object, start, 202 end); 203 } 204 205 static __inline void 206 vm_pager_release_writecount(vm_object_t object, vm_offset_t start, 207 vm_offset_t end) 208 { 209 210 if (pagertab[object->type]->pgo_release_writecount) 211 pagertab[object->type]->pgo_release_writecount(object, start, 212 end); 213 } 214 215 struct cdev_pager_ops { 216 int (*cdev_pg_fault)(vm_object_t vm_obj, vm_ooffset_t offset, 217 int prot, vm_page_t *mres); 218 int (*cdev_pg_populate)(vm_object_t vm_obj, vm_pindex_t pidx, 219 int fault_type, vm_prot_t max_prot, vm_pindex_t *first, 220 vm_pindex_t *last); 221 int (*cdev_pg_ctor)(void *handle, vm_ooffset_t size, vm_prot_t prot, 222 vm_ooffset_t foff, struct ucred *cred, u_short *color); 223 void (*cdev_pg_dtor)(void *handle); 224 }; 225 226 vm_object_t cdev_pager_allocate(void *handle, enum obj_type tp, 227 struct cdev_pager_ops *ops, vm_ooffset_t size, vm_prot_t prot, 228 vm_ooffset_t foff, struct ucred *cred); 229 vm_object_t cdev_pager_lookup(void *handle); 230 void cdev_pager_free_page(vm_object_t object, vm_page_t m); 231 232 #endif /* _KERNEL */ 233 #endif /* _VM_PAGER_ */ 234