sys/vm/vm_object.h

   1 /*
   2  * Copyright (c) 1991, 1993
   3  *      The Regents of the University of California.  All rights reserved.
   4  *
   5  * This code is derived from software contributed to Berkeley by
   6  * The Mach Operating System project at Carnegie-Mellon University.
   7  *
   8  * Redistribution and use in source and binary forms, with or without
   9  * modification, are permitted provided that the following conditions
  10  * are met:
  11  * 1. Redistributions of source code must retain the above copyright
  12  *    notice, this list of conditions and the following disclaimer.
  13  * 2. Redistributions in binary form must reproduce the above copyright
  14  *    notice, this list of conditions and the following disclaimer in the
  15  *    documentation and/or other materials provided with the distribution.
  16  * 3. All advertising materials mentioning features or use of this software
  17  *    must display the following acknowledgement:
  18  *      This product includes software developed by the University of
  19  *      California, Berkeley and its contributors.
  20  * 4. 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  *      from: @(#)vm_object.h   8.3 (Berkeley) 1/12/94
  37  *
  38  *
  39  * Copyright (c) 1987, 1990 Carnegie-Mellon University.
  40  * All rights reserved.
  41  *
  42  * Authors: Avadis Tevanian, Jr., Michael Wayne Young
  43  *
  44  * Permission to use, copy, modify and distribute this software and
  45  * its documentation is hereby granted, provided that both the copyright
  46  * notice and this permission notice appear in all copies of the
  47  * software, derivative works or modified versions, and any portions
  48  * thereof, and that both notices appear in supporting documentation.
  49  *
  50  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  51  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
  52  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  53  *
  54  * Carnegie Mellon requests users of this software to return to
  55  *
  56  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  57  *  School of Computer Science
  58  *  Carnegie Mellon University
  59  *  Pittsburgh PA 15213-3890
  60  *
  61  * any improvements or extensions that they make and grant Carnegie the
  62  * rights to redistribute these changes.
  63  *
  64  * $FreeBSD: src/sys/vm/vm_object.h,v 1.63.2.3 2003/05/26 19:17:56 alc Exp $
  65  * $DragonFly: src/sys/vm/vm_object.h,v 1.4 2003/08/20 08:03:01 rob Exp $
  66  */
  67
  68 /*
  69  *      Virtual memory object module definitions.
  70  */
  71
  72 #ifndef _VM_OBJECT_
  73 #define _VM_OBJECT_
  74
  75 #include <sys/queue.h>
  76 #include <machine/atomic.h>
  77
  78 enum obj_type { OBJT_DEFAULT, OBJT_SWAP, OBJT_VNODE, OBJT_DEVICE, OBJT_PHYS,
  79                 OBJT_DEAD };
  80 typedef u_char objtype_t;
  81
  82 /*
  83  * vm_object_lock       A lock covering byte ranges within a VM object
  84  *
  85  */
  86 struct vm_object_lock {
  87         struct vm_object_lock *next;
  88         int     type;                   /* type of lock */
  89         int     waiting;                /* someone is waiting on the lock */
  90         off_t   base;                   /* byte offset into object */
  91         off_t   bytes;                  /* extent in bytes */
  92 };
  93
  94 #define VMOBJ_LOCK_SHARED       1
  95 #define VMOBJ_LOCK_EXCL         2
  96
  97 /*
  98  * vm_object            A VM object which represents an arbitrarily sized
  99  *                      data store.
 100  */
 101 struct vm_object {
 102         TAILQ_ENTRY(vm_object) object_list; /* list of all objects */
 103         LIST_HEAD(, vm_object) shadow_head; /* objects that this is a shadow for */
 104         LIST_ENTRY(vm_object) shadow_list; /* chain of shadow objects */
 105         TAILQ_HEAD(, vm_page) memq;     /* list of resident pages */
 106         int generation;                 /* generation ID */
 107         vm_size_t size;                 /* Object size */
 108         int ref_count;                  /* How many refs?? */
 109         int shadow_count;               /* how many objects that this is a shadow for */
 110         int hash_rand;                  /* vm hash table randomizer     */
 111         objtype_t type;                 /* type of pager */
 112         u_short flags;                  /* see below */
 113         u_short pg_color;               /* color of first page in obj */
 114         u_short paging_in_progress;     /* Paging (in or out) so don't collapse or destroy */
 115         int resident_page_count;        /* number of resident pages */
 116         struct vm_object *backing_object; /* object that I'm a shadow of */
 117         vm_ooffset_t backing_object_offset;/* Offset in backing object */
 118         TAILQ_ENTRY(vm_object) pager_object_list; /* list of all objects of this pager type */
 119         void *handle;
 120         vm_object_lock_t range_locks;
 121         union {
 122                 /*
 123                  * VNode pager
 124                  *
 125                  *      vnp_size - current size of file
 126                  */
 127                 struct {
 128                         off_t vnp_size;
 129                 } vnp;
 130
 131                 /*
 132                  * Device pager
 133                  *
 134                  *      devp_pglist - list of allocated pages
 135                  */
 136                 struct {
 137                         TAILQ_HEAD(, vm_page) devp_pglist;
 138                 } devp;
 139
 140                 /*
 141                  * Swap pager
 142                  *
 143                  *      swp_bcount - number of swap 'swblock' metablocks, each
 144                  *                   contains up to 16 swapblk assignments.
 145                  *                   see vm/swap_pager.h
 146                  */
 147                 struct {
 148                         int swp_bcount;
 149                 } swp;
 150         } un_pager;
 151 };
 152
 153 /*
 154  * Flags
 155  */
 156 #define OBJ_ACTIVE      0x0004          /* active objects */
 157 #define OBJ_DEAD        0x0008          /* dead objects (during rundown) */
 158 #define OBJ_NOSPLIT     0x0010          /* dont split this object */
 159 #define OBJ_PIPWNT      0x0040          /* paging in progress wanted */
 160 #define OBJ_WRITEABLE   0x0080          /* object has been made writable */
 161 #define OBJ_MIGHTBEDIRTY 0x0100         /* object might be dirty */
 162 #define OBJ_CLEANING    0x0200
 163 #define OBJ_OPT         0x1000          /* I/O optimization */
 164 #define OBJ_ONEMAPPING  0x2000          /* One USE (a single, non-forked) mapping flag */
 165
 166 #define IDX_TO_OFF(idx) (((vm_ooffset_t)(idx)) << PAGE_SHIFT)
 167 #define OFF_TO_IDX(off) ((vm_pindex_t)(((vm_ooffset_t)(off)) >> PAGE_SHIFT))
 168
 169 #ifdef  _KERNEL
 170
 171 #define OBJPC_SYNC      0x1                     /* sync I/O */
 172 #define OBJPC_INVAL     0x2                     /* invalidate */
 173 #define OBJPC_NOSYNC    0x4                     /* skip if PG_NOSYNC */
 174
 175 TAILQ_HEAD(object_q, vm_object);
 176
 177 extern struct object_q vm_object_list;  /* list of allocated objects */
 178
 179  /* lock for object list and count */
 180
 181 extern vm_object_t kernel_object;       /* the single kernel object */
 182 extern vm_object_t kmem_object;
 183
 184 #endif                          /* _KERNEL */
 185
 186 #ifdef _KERNEL
 187
 188 static __inline void
 189 vm_object_set_flag(vm_object_t object, u_int bits)
 190 {
 191         atomic_set_short(&object->flags, bits);
 192 }
 193
 194 static __inline void
 195 vm_object_clear_flag(vm_object_t object, u_int bits)
 196 {
 197         atomic_clear_short(&object->flags, bits);
 198 }
 199
 200 static __inline void
 201 vm_object_pip_add(vm_object_t object, int i)
 202 {
 203         atomic_add_short(&object->paging_in_progress, i);
 204 }
 205
 206 static __inline void
 207 vm_object_pip_subtract(vm_object_t object, int i)
 208 {
 209         atomic_subtract_short(&object->paging_in_progress, i);
 210 }
 211
 212 static __inline void
 213 vm_object_pip_wakeup(vm_object_t object)
 214 {
 215         atomic_subtract_short(&object->paging_in_progress, 1);
 216         if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
 217                 vm_object_clear_flag(object, OBJ_PIPWNT);
 218                 wakeup(object);
 219         }
 220 }
 221
 222 static __inline void
 223 vm_object_pip_wakeupn(vm_object_t object, int i)
 224 {
 225         if (i)
 226                 atomic_subtract_short(&object->paging_in_progress, i);
 227         if ((object->flags & OBJ_PIPWNT) && object->paging_in_progress == 0) {
 228                 vm_object_clear_flag(object, OBJ_PIPWNT);
 229                 wakeup(object);
 230         }
 231 }
 232
 233 static __inline void
 234 vm_object_pip_sleep(vm_object_t object, char *waitid)
 235 {
 236         if (object->paging_in_progress) {
 237                 int s = splvm();
 238                 if (object->paging_in_progress) {
 239                         vm_object_set_flag(object, OBJ_PIPWNT);
 240                         tsleep(object, 0, waitid, 0);
 241                 }
 242                 splx(s);
 243         }
 244 }
 245
 246 static __inline void
 247 vm_object_pip_wait(vm_object_t object, char *waitid)
 248 {
 249         while (object->paging_in_progress)
 250                 vm_object_pip_sleep(object, waitid);
 251 }
 252
 253 vm_object_t vm_object_allocate (objtype_t, vm_size_t);
 254 void _vm_object_allocate (objtype_t, vm_size_t, vm_object_t);
 255 boolean_t vm_object_coalesce (vm_object_t, vm_pindex_t, vm_size_t, vm_size_t);
 256 void vm_object_collapse (vm_object_t);
 257 void vm_object_deallocate (vm_object_t);
 258 void vm_object_terminate (vm_object_t);
 259 void vm_object_vndeallocate (vm_object_t);
 260 void vm_object_set_writeable_dirty (vm_object_t);
 261 void vm_object_init (void);
 262 void vm_object_page_clean (vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t);
 263 void vm_object_page_remove (vm_object_t, vm_pindex_t, vm_pindex_t, boolean_t);
 264 void vm_object_pmap_copy (vm_object_t, vm_pindex_t, vm_pindex_t);
 265 void vm_object_pmap_copy_1 (vm_object_t, vm_pindex_t, vm_pindex_t);
 266 void vm_object_pmap_remove (vm_object_t, vm_pindex_t, vm_pindex_t);
 267 void vm_object_reference (vm_object_t);
 268 void vm_object_shadow (vm_object_t *, vm_ooffset_t *, vm_size_t);
 269 void vm_object_madvise (vm_object_t, vm_pindex_t, int, int);
 270 void vm_object_init2 (void);
 271 #endif                          /* _KERNEL */
 272
 273 #endif                          /* _VM_OBJECT_ */