vm_object.h revision 315563
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 * 4. Neither the name of the University nor the names of its contributors 17 * may be used to endorse or promote products derived from this software 18 * without specific prior written permission. 19 * 20 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 23 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 30 * SUCH DAMAGE. 31 * 32 * from: @(#)vm_object.h 8.3 (Berkeley) 1/12/94 33 * 34 * 35 * Copyright (c) 1987, 1990 Carnegie-Mellon University. 36 * All rights reserved. 37 * 38 * Authors: Avadis Tevanian, Jr., Michael Wayne Young 39 * 40 * Permission to use, copy, modify and distribute this software and 41 * its documentation is hereby granted, provided that both the copyright 42 * notice and this permission notice appear in all copies of the 43 * software, derivative works or modified versions, and any portions 44 * thereof, and that both notices appear in supporting documentation. 45 * 46 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS" 47 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND 48 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE. 49 * 50 * Carnegie Mellon requests users of this software to return to 51 * 52 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU 53 * School of Computer Science 54 * Carnegie Mellon University 55 * Pittsburgh PA 15213-3890 56 * 57 * any improvements or extensions that they make and grant Carnegie the 58 * rights to redistribute these changes. 59 * 60 * $FreeBSD: stable/11/sys/vm/vm_object.h 315563 2017-03-19 16:01:44Z kib $ 61 */ 62 63/* 64 * Virtual memory object module definitions. 65 */ 66 67#ifndef _VM_OBJECT_ 68#define _VM_OBJECT_ 69 70#include <sys/queue.h> 71#include <sys/_lock.h> 72#include <sys/_mutex.h> 73#include <sys/_rwlock.h> 74 75#include <vm/_vm_radix.h> 76 77/* 78 * Types defined: 79 * 80 * vm_object_t Virtual memory object. 81 * 82 * The root of cached pages pool is protected by both the per-object lock 83 * and the free pages queue mutex. 84 * On insert in the cache radix trie, the per-object lock is expected 85 * to be already held and the free pages queue mutex will be 86 * acquired during the operation too. 87 * On remove and lookup from the cache radix trie, only the free 88 * pages queue mutex is expected to be locked. 89 * These rules allow for reliably checking for the presence of cached 90 * pages with only the per-object lock held, thereby reducing contention 91 * for the free pages queue mutex. 92 * 93 * List of locks 94 * (c) const until freed 95 * (o) per-object lock 96 * (f) free pages queue mutex 97 * 98 */ 99 100struct vm_object { 101 struct rwlock lock; 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(respgs, vm_page) memq; /* list of resident pages */ 106 struct vm_radix rtree; /* root of the resident page radix trie*/ 107 vm_pindex_t size; /* Object size */ 108 int generation; /* generation ID */ 109 int ref_count; /* How many refs?? */ 110 int shadow_count; /* how many objects that this is a shadow for */ 111 vm_memattr_t memattr; /* default memory attribute for pages */ 112 objtype_t type; /* type of pager */ 113 u_short flags; /* see below */ 114 u_short pg_color; /* (c) color of first page in obj */ 115 u_int paging_in_progress; /* Paging (in or out) so don't collapse or destroy */ 116 int resident_page_count; /* number of resident pages */ 117 struct vm_object *backing_object; /* object that I'm a shadow of */ 118 vm_ooffset_t backing_object_offset;/* Offset in backing object */ 119 TAILQ_ENTRY(vm_object) pager_object_list; /* list of all objects of this pager type */ 120 LIST_HEAD(, vm_reserv) rvq; /* list of reservations */ 121 struct vm_radix cache; /* (o + f) root of the cache page radix trie */ 122 void *handle; 123 union { 124 /* 125 * VNode pager 126 * 127 * vnp_size - current size of file 128 */ 129 struct { 130 off_t vnp_size; 131 vm_ooffset_t writemappings; 132 } vnp; 133 134 /* 135 * Device pager 136 * 137 * devp_pglist - list of allocated pages 138 */ 139 struct { 140 TAILQ_HEAD(, vm_page) devp_pglist; 141 struct cdev_pager_ops *ops; 142 struct cdev *dev; 143 } devp; 144 145 /* 146 * SG pager 147 * 148 * sgp_pglist - list of allocated pages 149 */ 150 struct { 151 TAILQ_HEAD(, vm_page) sgp_pglist; 152 } sgp; 153 154 /* 155 * Swap pager 156 * 157 * swp_tmpfs - back-pointer to the tmpfs vnode, 158 * if any, which uses the vm object 159 * as backing store. The handle 160 * cannot be reused for linking, 161 * because the vnode can be 162 * reclaimed and recreated, making 163 * the handle changed and hash-chain 164 * invalid. 165 * 166 * swp_bcount - number of swap 'swblock' metablocks, each 167 * contains up to 16 swapblk assignments. 168 * see vm/swap_pager.h 169 */ 170 struct { 171 void *swp_tmpfs; 172 int swp_bcount; 173 } swp; 174 } un_pager; 175 struct ucred *cred; 176 vm_ooffset_t charge; 177 void *umtx_data; 178}; 179 180/* 181 * Flags 182 */ 183#define OBJ_FICTITIOUS 0x0001 /* (c) contains fictitious pages */ 184#define OBJ_UNMANAGED 0x0002 /* (c) contains unmanaged pages */ 185#define OBJ_POPULATE 0x0004 /* pager implements populate() */ 186#define OBJ_DEAD 0x0008 /* dead objects (during rundown) */ 187#define OBJ_NOSPLIT 0x0010 /* dont split this object */ 188#define OBJ_UMTXDEAD 0x0020 /* umtx pshared was terminated */ 189#define OBJ_PIPWNT 0x0040 /* paging in progress wanted */ 190#define OBJ_MIGHTBEDIRTY 0x0100 /* object might be dirty, only for vnode */ 191#define OBJ_TMPFS_NODE 0x0200 /* object belongs to tmpfs VREG node */ 192#define OBJ_TMPFS_DIRTY 0x0400 /* dirty tmpfs obj */ 193#define OBJ_COLORED 0x1000 /* pg_color is defined */ 194#define OBJ_ONEMAPPING 0x2000 /* One USE (a single, non-forked) mapping flag */ 195#define OBJ_DISCONNECTWNT 0x4000 /* disconnect from vnode wanted */ 196#define OBJ_TMPFS 0x8000 /* has tmpfs vnode allocated */ 197 198/* 199 * Helpers to perform conversion between vm_object page indexes and offsets. 200 * IDX_TO_OFF() converts an index into an offset. 201 * OFF_TO_IDX() converts an offset into an index. Since offsets are signed 202 * by default, the sign propagation in OFF_TO_IDX(), when applied to 203 * negative offsets, is intentional and returns a vm_object page index 204 * that cannot be created by a userspace mapping. 205 * UOFF_TO_IDX() treats the offset as an unsigned value and converts it 206 * into an index accordingly. Use it only when the full range of offset 207 * values are allowed. Currently, this only applies to device mappings. 208 * OBJ_MAX_SIZE specifies the maximum page index corresponding to the 209 * maximum unsigned offset. 210 */ 211#define IDX_TO_OFF(idx) (((vm_ooffset_t)(idx)) << PAGE_SHIFT) 212#define OFF_TO_IDX(off) ((vm_pindex_t)(((vm_ooffset_t)(off)) >> PAGE_SHIFT)) 213#define UOFF_TO_IDX(off) (((vm_pindex_t)(off)) >> PAGE_SHIFT) 214#define OBJ_MAX_SIZE (UOFF_TO_IDX(UINT64_MAX) + 1) 215 216#ifdef _KERNEL 217 218#define OBJPC_SYNC 0x1 /* sync I/O */ 219#define OBJPC_INVAL 0x2 /* invalidate */ 220#define OBJPC_NOSYNC 0x4 /* skip if VPO_NOSYNC */ 221 222/* 223 * The following options are supported by vm_object_page_remove(). 224 */ 225#define OBJPR_CLEANONLY 0x1 /* Don't remove dirty pages. */ 226#define OBJPR_NOTMAPPED 0x2 /* Don't unmap pages. */ 227 228TAILQ_HEAD(object_q, vm_object); 229 230extern struct object_q vm_object_list; /* list of allocated objects */ 231extern struct mtx vm_object_list_mtx; /* lock for object list and count */ 232 233extern struct vm_object kernel_object_store; 234extern struct vm_object kmem_object_store; 235 236#define kernel_object (&kernel_object_store) 237#define kmem_object (&kmem_object_store) 238 239#define VM_OBJECT_ASSERT_LOCKED(object) \ 240 rw_assert(&(object)->lock, RA_LOCKED) 241#define VM_OBJECT_ASSERT_RLOCKED(object) \ 242 rw_assert(&(object)->lock, RA_RLOCKED) 243#define VM_OBJECT_ASSERT_WLOCKED(object) \ 244 rw_assert(&(object)->lock, RA_WLOCKED) 245#define VM_OBJECT_ASSERT_UNLOCKED(object) \ 246 rw_assert(&(object)->lock, RA_UNLOCKED) 247#define VM_OBJECT_LOCK_DOWNGRADE(object) \ 248 rw_downgrade(&(object)->lock) 249#define VM_OBJECT_RLOCK(object) \ 250 rw_rlock(&(object)->lock) 251#define VM_OBJECT_RUNLOCK(object) \ 252 rw_runlock(&(object)->lock) 253#define VM_OBJECT_SLEEP(object, wchan, pri, wmesg, timo) \ 254 rw_sleep((wchan), &(object)->lock, (pri), (wmesg), (timo)) 255#define VM_OBJECT_TRYRLOCK(object) \ 256 rw_try_rlock(&(object)->lock) 257#define VM_OBJECT_TRYWLOCK(object) \ 258 rw_try_wlock(&(object)->lock) 259#define VM_OBJECT_TRYUPGRADE(object) \ 260 rw_try_upgrade(&(object)->lock) 261#define VM_OBJECT_WLOCK(object) \ 262 rw_wlock(&(object)->lock) 263#define VM_OBJECT_WOWNED(object) \ 264 rw_wowned(&(object)->lock) 265#define VM_OBJECT_WUNLOCK(object) \ 266 rw_wunlock(&(object)->lock) 267 268/* 269 * The object must be locked or thread private. 270 */ 271static __inline void 272vm_object_set_flag(vm_object_t object, u_short bits) 273{ 274 275 object->flags |= bits; 276} 277 278/* 279 * Conditionally set the object's color, which (1) enables the allocation 280 * of physical memory reservations for anonymous objects and larger-than- 281 * superpage-sized named objects and (2) determines the first page offset 282 * within the object at which a reservation may be allocated. In other 283 * words, the color determines the alignment of the object with respect 284 * to the largest superpage boundary. When mapping named objects, like 285 * files or POSIX shared memory objects, the color should be set to zero 286 * before a virtual address is selected for the mapping. In contrast, 287 * for anonymous objects, the color may be set after the virtual address 288 * is selected. 289 * 290 * The object must be locked. 291 */ 292static __inline void 293vm_object_color(vm_object_t object, u_short color) 294{ 295 296 if ((object->flags & OBJ_COLORED) == 0) { 297 object->pg_color = color; 298 object->flags |= OBJ_COLORED; 299 } 300} 301 302void vm_object_clear_flag(vm_object_t object, u_short bits); 303void vm_object_pip_add(vm_object_t object, short i); 304void vm_object_pip_subtract(vm_object_t object, short i); 305void vm_object_pip_wakeup(vm_object_t object); 306void vm_object_pip_wakeupn(vm_object_t object, short i); 307void vm_object_pip_wait(vm_object_t object, char *waitid); 308 309static __inline boolean_t 310vm_object_cache_is_empty(vm_object_t object) 311{ 312 313 return (vm_radix_is_empty(&object->cache)); 314} 315 316void umtx_shm_object_init(vm_object_t object); 317void umtx_shm_object_terminated(vm_object_t object); 318extern int umtx_shm_vnobj_persistent; 319 320vm_object_t vm_object_allocate (objtype_t, vm_pindex_t); 321boolean_t vm_object_coalesce(vm_object_t, vm_ooffset_t, vm_size_t, vm_size_t, 322 boolean_t); 323void vm_object_collapse (vm_object_t); 324void vm_object_deallocate (vm_object_t); 325void vm_object_destroy (vm_object_t); 326void vm_object_terminate (vm_object_t); 327void vm_object_set_writeable_dirty (vm_object_t); 328void vm_object_init (void); 329void vm_object_madvise(vm_object_t, vm_pindex_t, vm_pindex_t, int); 330boolean_t vm_object_page_clean(vm_object_t object, vm_ooffset_t start, 331 vm_ooffset_t end, int flags); 332void vm_object_page_noreuse(vm_object_t object, vm_pindex_t start, 333 vm_pindex_t end); 334void vm_object_page_remove(vm_object_t object, vm_pindex_t start, 335 vm_pindex_t end, int options); 336boolean_t vm_object_populate(vm_object_t, vm_pindex_t, vm_pindex_t); 337void vm_object_print(long addr, boolean_t have_addr, long count, char *modif); 338void vm_object_reference (vm_object_t); 339void vm_object_reference_locked(vm_object_t); 340int vm_object_set_memattr(vm_object_t object, vm_memattr_t memattr); 341void vm_object_shadow (vm_object_t *, vm_ooffset_t *, vm_size_t); 342void vm_object_split(vm_map_entry_t); 343boolean_t vm_object_sync(vm_object_t, vm_ooffset_t, vm_size_t, boolean_t, 344 boolean_t); 345void vm_object_unwire(vm_object_t object, vm_ooffset_t offset, 346 vm_size_t length, uint8_t queue); 347struct vnode *vm_object_vnode(vm_object_t object); 348#endif /* _KERNEL */ 349 350#endif /* _VM_OBJECT_ */ 351