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  * 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  * $FreeBSD$
  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
 100 struct 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_DEAD        0x0008          /* dead objects (during rundown) */
 186 #define OBJ_NOSPLIT     0x0010          /* dont split this object */
 187 #define OBJ_UMTXDEAD    0x0020          /* umtx pshared was terminated */
 188 #define OBJ_PIPWNT      0x0040          /* paging in progress wanted */
 189 #define OBJ_MIGHTBEDIRTY 0x0100         /* object might be dirty, only for vnode */
 190 #define OBJ_TMPFS_NODE  0x0200          /* object belongs to tmpfs VREG node */
 191 #define OBJ_TMPFS_DIRTY 0x0400          /* dirty tmpfs obj */
 192 #define OBJ_COLORED     0x1000          /* pg_color is defined */
 193 #define OBJ_ONEMAPPING  0x2000          /* One USE (a single, non-forked) mapping flag */
 194 #define OBJ_DISCONNECTWNT 0x4000        /* disconnect from vnode wanted */
 195 #define OBJ_TMPFS       0x8000          /* has tmpfs vnode allocated */
 196
 197 #define IDX_TO_OFF(idx) (((vm_ooffset_t)(idx)) << PAGE_SHIFT)
 198 #define OFF_TO_IDX(off) ((vm_pindex_t)(((vm_ooffset_t)(off)) >> PAGE_SHIFT))
 199
 200 #ifdef  _KERNEL
 201
 202 #define OBJPC_SYNC      0x1                     /* sync I/O */
 203 #define OBJPC_INVAL     0x2                     /* invalidate */
 204 #define OBJPC_NOSYNC    0x4                     /* skip if VPO_NOSYNC */
 205
 206 /*
 207  * The following options are supported by vm_object_page_remove().
 208  */
 209 #define OBJPR_CLEANONLY 0x1             /* Don't remove dirty pages. */
 210 #define OBJPR_NOTMAPPED 0x2             /* Don't unmap pages. */
 211
 212 TAILQ_HEAD(object_q, vm_object);
 213
 214 extern struct object_q vm_object_list;  /* list of allocated objects */
 215 extern struct mtx vm_object_list_mtx;   /* lock for object list and count */
 216
 217 extern struct vm_object kernel_object_store;
 218 extern struct vm_object kmem_object_store;
 219
 220 #define kernel_object   (&kernel_object_store)
 221 #define kmem_object     (&kmem_object_store)
 222
 223 #define VM_OBJECT_ASSERT_LOCKED(object)                                 \
 224         rw_assert(&(object)->lock, RA_LOCKED)
 225 #define VM_OBJECT_ASSERT_RLOCKED(object)                                \
 226         rw_assert(&(object)->lock, RA_RLOCKED)
 227 #define VM_OBJECT_ASSERT_WLOCKED(object)                                \
 228         rw_assert(&(object)->lock, RA_WLOCKED)
 229 #define VM_OBJECT_ASSERT_UNLOCKED(object)                               \
 230         rw_assert(&(object)->lock, RA_UNLOCKED)
 231 #define VM_OBJECT_LOCK_DOWNGRADE(object)                                \
 232         rw_downgrade(&(object)->lock)
 233 #define VM_OBJECT_RLOCK(object)                                         \
 234         rw_rlock(&(object)->lock)
 235 #define VM_OBJECT_RUNLOCK(object)                                       \
 236         rw_runlock(&(object)->lock)
 237 #define VM_OBJECT_SLEEP(object, wchan, pri, wmesg, timo)                \
 238         rw_sleep((wchan), &(object)->lock, (pri), (wmesg), (timo))
 239 #define VM_OBJECT_TRYRLOCK(object)                                      \
 240         rw_try_rlock(&(object)->lock)
 241 #define VM_OBJECT_TRYWLOCK(object)                                      \
 242         rw_try_wlock(&(object)->lock)
 243 #define VM_OBJECT_TRYUPGRADE(object)                                    \
 244         rw_try_upgrade(&(object)->lock)
 245 #define VM_OBJECT_WLOCK(object)                                         \
 246         rw_wlock(&(object)->lock)
 247 #define VM_OBJECT_WOWNED(object)                                        \
 248         rw_wowned(&(object)->lock)
 249 #define VM_OBJECT_WUNLOCK(object)                                       \
 250         rw_wunlock(&(object)->lock)
 251
 252 /*
 253  *      The object must be locked or thread private.
 254  */
 255 static __inline void
 256 vm_object_set_flag(vm_object_t object, u_short bits)
 257 {
 258
 259         object->flags |= bits;
 260 }
 261
 262 /*
 263  *      Conditionally set the object's color, which (1) enables the allocation
 264  *      of physical memory reservations for anonymous objects and larger-than-
 265  *      superpage-sized named objects and (2) determines the first page offset
 266  *      within the object at which a reservation may be allocated.  In other
 267  *      words, the color determines the alignment of the object with respect
 268  *      to the largest superpage boundary.  When mapping named objects, like
 269  *      files or POSIX shared memory objects, the color should be set to zero
 270  *      before a virtual address is selected for the mapping.  In contrast,
 271  *      for anonymous objects, the color may be set after the virtual address
 272  *      is selected.
 273  *
 274  *      The object must be locked.
 275  */
 276 static __inline void
 277 vm_object_color(vm_object_t object, u_short color)
 278 {
 279
 280         if ((object->flags & OBJ_COLORED) == 0) {
 281                 object->pg_color = color;
 282                 object->flags |= OBJ_COLORED;
 283         }
 284 }
 285
 286 void vm_object_clear_flag(vm_object_t object, u_short bits);
 287 void vm_object_pip_add(vm_object_t object, short i);
 288 void vm_object_pip_subtract(vm_object_t object, short i);
 289 void vm_object_pip_wakeup(vm_object_t object);
 290 void vm_object_pip_wakeupn(vm_object_t object, short i);
 291 void vm_object_pip_wait(vm_object_t object, char *waitid);
 292
 293 static __inline boolean_t
 294 vm_object_cache_is_empty(vm_object_t object)
 295 {
 296
 297         return (vm_radix_is_empty(&object->cache));
 298 }
 299
 300 void umtx_shm_object_init(vm_object_t object);
 301 void umtx_shm_object_terminated(vm_object_t object);
 302 extern int umtx_shm_vnobj_persistent;
 303
 304 vm_object_t vm_object_allocate (objtype_t, vm_pindex_t);
 305 boolean_t vm_object_coalesce(vm_object_t, vm_ooffset_t, vm_size_t, vm_size_t,
 306    boolean_t);
 307 void vm_object_collapse (vm_object_t);
 308 void vm_object_deallocate (vm_object_t);
 309 void vm_object_destroy (vm_object_t);
 310 void vm_object_terminate (vm_object_t);
 311 void vm_object_set_writeable_dirty (vm_object_t);
 312 void vm_object_init (void);
 313 void vm_object_madvise(vm_object_t, vm_pindex_t, vm_pindex_t, int);
 314 boolean_t vm_object_page_clean(vm_object_t object, vm_ooffset_t start,
 315     vm_ooffset_t end, int flags);
 316 void vm_object_page_noreuse(vm_object_t object, vm_pindex_t start,
 317     vm_pindex_t end);
 318 void vm_object_page_remove(vm_object_t object, vm_pindex_t start,
 319     vm_pindex_t end, int options);
 320 boolean_t vm_object_populate(vm_object_t, vm_pindex_t, vm_pindex_t);
 321 void vm_object_print(long addr, boolean_t have_addr, long count, char *modif);
 322 void vm_object_reference (vm_object_t);
 323 void vm_object_reference_locked(vm_object_t);
 324 int  vm_object_set_memattr(vm_object_t object, vm_memattr_t memattr);
 325 void vm_object_shadow (vm_object_t *, vm_ooffset_t *, vm_size_t);
 326 void vm_object_split(vm_map_entry_t);
 327 boolean_t vm_object_sync(vm_object_t, vm_ooffset_t, vm_size_t, boolean_t,
 328     boolean_t);
 329 void vm_object_unwire(vm_object_t object, vm_ooffset_t offset,
 330     vm_size_t length, uint8_t queue);
 331 struct vnode *vm_object_vnode(vm_object_t object);
 332 #endif                          /* _KERNEL */
 333
 334 #endif                          /* _VM_OBJECT_ */