sys/vm/vm_object.h

   1 /*-
   2  * SPDX-License-Identifier: (BSD-3-Clause AND MIT-CMU)
   3  *
   4  * Copyright (c) 1991, 1993
   5  *      The Regents of the University of California.  All rights reserved.
   6  *
   7  * This code is derived from software contributed to Berkeley by
   8  * The Mach Operating System project at Carnegie-Mellon University.
   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  * 3. 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  *      from: @(#)vm_object.h   8.3 (Berkeley) 1/12/94
  35  *
  36  *
  37  * Copyright (c) 1987, 1990 Carnegie-Mellon University.
  38  * All rights reserved.
  39  *
  40  * Authors: Avadis Tevanian, Jr., Michael Wayne Young
  41  *
  42  * Permission to use, copy, modify and distribute this software and
  43  * its documentation is hereby granted, provided that both the copyright
  44  * notice and this permission notice appear in all copies of the
  45  * software, derivative works or modified versions, and any portions
  46  * thereof, and that both notices appear in supporting documentation.
  47  *
  48  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
  49  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
  50  * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
  51  *
  52  * Carnegie Mellon requests users of this software to return to
  53  *
  54  *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
  55  *  School of Computer Science
  56  *  Carnegie Mellon University
  57  *  Pittsburgh PA 15213-3890
  58  *
  59  * any improvements or extensions that they make and grant Carnegie the
  60  * rights to redistribute these changes.
  61  *
  62  * $FreeBSD$
  63  */
  64
  65 /*
  66  *      Virtual memory object module definitions.
  67  */
  68
  69 #ifndef _VM_OBJECT_
  70 #define _VM_OBJECT_
  71
  72 #include <sys/queue.h>
  73 #include <sys/_blockcount.h>
  74 #include <sys/_lock.h>
  75 #include <sys/_mutex.h>
  76 #include <sys/_pctrie.h>
  77 #include <sys/_rwlock.h>
  78 #include <sys/_domainset.h>
  79
  80 #include <vm/_vm_radix.h>
  81
  82 /*
  83  *      Types defined:
  84  *
  85  *      vm_object_t             Virtual memory object.
  86  *
  87  * List of locks
  88  *      (a)     atomic
  89  *      (c)     const until freed
  90  *      (o)     per-object lock
  91  *      (f)     free pages queue mutex
  92  *
  93  */
  94
  95 #ifndef VM_PAGE_HAVE_PGLIST
  96 TAILQ_HEAD(pglist, vm_page);
  97 #define VM_PAGE_HAVE_PGLIST
  98 #endif
  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         struct pglist 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         struct domainset_ref domain;    /* NUMA policy. */
 109         volatile int generation;        /* generation ID */
 110         int cleangeneration;            /* Generation at clean time */
 111         volatile u_int ref_count;       /* How many refs?? */
 112         int shadow_count;               /* how many objects that this is a shadow for */
 113         vm_memattr_t memattr;           /* default memory attribute for pages */
 114         objtype_t type;                 /* type of pager */
 115         u_short flags;                  /* see below */
 116         u_short pg_color;               /* (c) color of first page in obj */
 117         blockcount_t paging_in_progress; /* (a) Paging (in or out) so don't collapse or destroy */
 118         blockcount_t busy;              /* (a) object is busy, disallow page busy. */
 119         int resident_page_count;        /* number of resident pages */
 120         struct vm_object *backing_object; /* object that I'm a shadow of */
 121         vm_ooffset_t backing_object_offset;/* Offset in backing object */
 122         TAILQ_ENTRY(vm_object) pager_object_list; /* list of all objects of this pager type */
 123         LIST_HEAD(, vm_reserv) rvq;     /* list of reservations */
 124         void *handle;
 125         union {
 126                 /*
 127                  * VNode pager
 128                  *
 129                  *      vnp_size - current size of file
 130                  */
 131                 struct {
 132                         off_t vnp_size;
 133                         vm_ooffset_t writemappings;
 134                 } vnp;
 135
 136                 /*
 137                  * Device pager
 138                  *
 139                  *      devp_pglist - list of allocated pages
 140                  */
 141                 struct {
 142                         TAILQ_HEAD(, vm_page) devp_pglist;
 143                         struct cdev_pager_ops *ops;
 144                         struct cdev *dev;
 145                 } devp;
 146
 147                 /*
 148                  * SG pager
 149                  *
 150                  *      sgp_pglist - list of allocated pages
 151                  */
 152                 struct {
 153                         TAILQ_HEAD(, vm_page) sgp_pglist;
 154                 } sgp;
 155
 156                 /*
 157                  * Swap pager
 158                  *
 159                  *      swp_tmpfs - back-pointer to the tmpfs vnode,
 160                  *                   if any, which uses the vm object
 161                  *                   as backing store.  The handle
 162                  *                   cannot be reused for linking,
 163                  *                   because the vnode can be
 164                  *                   reclaimed and recreated, making
 165                  *                   the handle changed and hash-chain
 166                  *                   invalid.
 167                  *
 168                  *      swp_blks -   pc-trie of the allocated swap blocks.
 169                  *
 170                  */
 171                 struct {
 172                         void *swp_tmpfs;
 173                         struct pctrie swp_blks;
 174                         vm_ooffset_t writemappings;
 175                 } swp;
 176         } un_pager;
 177         struct ucred *cred;
 178         vm_ooffset_t charge;
 179         void *umtx_data;
 180 };
 181
 182 /*
 183  * Flags
 184  */
 185 #define OBJ_FICTITIOUS  0x0001          /* (c) contains fictitious pages */
 186 #define OBJ_UNMANAGED   0x0002          /* (c) contains unmanaged pages */
 187 #define OBJ_POPULATE    0x0004          /* pager implements populate() */
 188 #define OBJ_DEAD        0x0008          /* dead objects (during rundown) */
 189 #define OBJ_ANON        0x0010          /* (c) contains anonymous memory */
 190 #define OBJ_UMTXDEAD    0x0020          /* umtx pshared was terminated */
 191 #define OBJ_SIZEVNLOCK  0x0040          /* lock vnode to check obj size */
 192 #define OBJ_PG_DTOR     0x0080          /* dont reset object, leave that for dtor */
 193 #define OBJ_TMPFS_NODE  0x0200          /* object belongs to tmpfs VREG node */
 194 #define OBJ_SPLIT       0x0400          /* object is being split */
 195 #define OBJ_COLLAPSING  0x0800          /* Parent of collapse. */
 196 #define OBJ_COLORED     0x1000          /* pg_color is defined */
 197 #define OBJ_ONEMAPPING  0x2000          /* One USE (a single, non-forked) mapping flag */
 198 #define OBJ_SHADOWLIST  0x4000          /* Object is on the shadow list. */
 199 #define OBJ_TMPFS       0x8000          /* has tmpfs vnode allocated */
 200
 201 /*
 202  * Helpers to perform conversion between vm_object page indexes and offsets.
 203  * IDX_TO_OFF() converts an index into an offset.
 204  * OFF_TO_IDX() converts an offset into an index.
 205  * OBJ_MAX_SIZE specifies the maximum page index corresponding to the
 206  *   maximum unsigned offset.
 207  */
 208 #define IDX_TO_OFF(idx) (((vm_ooffset_t)(idx)) << PAGE_SHIFT)
 209 #define OFF_TO_IDX(off) ((vm_pindex_t)(((vm_ooffset_t)(off)) >> PAGE_SHIFT))
 210 #define OBJ_MAX_SIZE    (OFF_TO_IDX(UINT64_MAX) + 1)
 211
 212 #ifdef  _KERNEL
 213
 214 #define OBJPC_SYNC      0x1                     /* sync I/O */
 215 #define OBJPC_INVAL     0x2                     /* invalidate */
 216 #define OBJPC_NOSYNC    0x4                     /* skip if PGA_NOSYNC */
 217
 218 /*
 219  * The following options are supported by vm_object_page_remove().
 220  */
 221 #define OBJPR_CLEANONLY 0x1             /* Don't remove dirty pages. */
 222 #define OBJPR_NOTMAPPED 0x2             /* Don't unmap pages. */
 223
 224 TAILQ_HEAD(object_q, vm_object);
 225
 226 extern struct object_q vm_object_list;  /* list of allocated objects */
 227 extern struct mtx vm_object_list_mtx;   /* lock for object list and count */
 228
 229 extern struct vm_object kernel_object_store;
 230
 231 /* kernel and kmem are aliased for backwards KPI compat. */
 232 #define kernel_object   (&kernel_object_store)
 233 #define kmem_object     (&kernel_object_store)
 234
 235 #define VM_OBJECT_ASSERT_LOCKED(object)                                 \
 236         rw_assert(&(object)->lock, RA_LOCKED)
 237 #define VM_OBJECT_ASSERT_RLOCKED(object)                                \
 238         rw_assert(&(object)->lock, RA_RLOCKED)
 239 #define VM_OBJECT_ASSERT_WLOCKED(object)                                \
 240         rw_assert(&(object)->lock, RA_WLOCKED)
 241 #define VM_OBJECT_ASSERT_UNLOCKED(object)                               \
 242         rw_assert(&(object)->lock, RA_UNLOCKED)
 243 #define VM_OBJECT_LOCK_DOWNGRADE(object)                                \
 244         rw_downgrade(&(object)->lock)
 245 #define VM_OBJECT_RLOCK(object)                                         \
 246         rw_rlock(&(object)->lock)
 247 #define VM_OBJECT_RUNLOCK(object)                                       \
 248         rw_runlock(&(object)->lock)
 249 #define VM_OBJECT_SLEEP(object, wchan, pri, wmesg, timo)                \
 250         rw_sleep((wchan), &(object)->lock, (pri), (wmesg), (timo))
 251 #define VM_OBJECT_TRYRLOCK(object)                                      \
 252         rw_try_rlock(&(object)->lock)
 253 #define VM_OBJECT_TRYWLOCK(object)                                      \
 254         rw_try_wlock(&(object)->lock)
 255 #define VM_OBJECT_TRYUPGRADE(object)                                    \
 256         rw_try_upgrade(&(object)->lock)
 257 #define VM_OBJECT_WLOCK(object)                                         \
 258         rw_wlock(&(object)->lock)
 259 #define VM_OBJECT_WOWNED(object)                                        \
 260         rw_wowned(&(object)->lock)
 261 #define VM_OBJECT_WUNLOCK(object)                                       \
 262         rw_wunlock(&(object)->lock)
 263 #define VM_OBJECT_DROP(object)                                          \
 264         lock_class_rw.lc_unlock(&(object)->lock.lock_object)
 265 #define VM_OBJECT_PICKUP(object, state)                                 \
 266         lock_class_rw.lc_lock(&(object)->lock.lock_object, (state))
 267
 268 #define VM_OBJECT_ASSERT_PAGING(object)                                 \
 269         KASSERT(blockcount_read(&(object)->paging_in_progress) != 0,    \
 270             ("vm_object %p is not paging", object))
 271 #define VM_OBJECT_ASSERT_REFERENCE(object)                              \
 272         KASSERT((object)->reference_count != 0,                         \
 273             ("vm_object %p is not referenced", object))
 274
 275 struct vnode;
 276
 277 /*
 278  *      The object must be locked or thread private.
 279  */
 280 static __inline void
 281 vm_object_set_flag(vm_object_t object, u_short bits)
 282 {
 283
 284         object->flags |= bits;
 285 }
 286
 287 /*
 288  *      Conditionally set the object's color, which (1) enables the allocation
 289  *      of physical memory reservations for anonymous objects and larger-than-
 290  *      superpage-sized named objects and (2) determines the first page offset
 291  *      within the object at which a reservation may be allocated.  In other
 292  *      words, the color determines the alignment of the object with respect
 293  *      to the largest superpage boundary.  When mapping named objects, like
 294  *      files or POSIX shared memory objects, the color should be set to zero
 295  *      before a virtual address is selected for the mapping.  In contrast,
 296  *      for anonymous objects, the color may be set after the virtual address
 297  *      is selected.
 298  *
 299  *      The object must be locked.
 300  */
 301 static __inline void
 302 vm_object_color(vm_object_t object, u_short color)
 303 {
 304
 305         if ((object->flags & OBJ_COLORED) == 0) {
 306                 object->pg_color = color;
 307                 object->flags |= OBJ_COLORED;
 308         }
 309 }
 310
 311 static __inline bool
 312 vm_object_reserv(vm_object_t object)
 313 {
 314
 315         if (object != NULL &&
 316             (object->flags & (OBJ_COLORED | OBJ_FICTITIOUS)) == OBJ_COLORED) {
 317                 return (true);
 318         }
 319         return (false);
 320 }
 321
 322 static __inline bool
 323 vm_object_mightbedirty(vm_object_t object)
 324 {
 325
 326         if (object->type != OBJT_VNODE) {
 327                 if ((object->flags & OBJ_TMPFS_NODE) == 0)
 328                         return (false);
 329 #ifdef KASSERT
 330                 KASSERT(object->type == OBJT_SWAP,
 331                     ("TMPFS_NODE obj %p is not swap", object));
 332 #endif
 333         }
 334         return (object->generation != object->cleangeneration);
 335 }
 336
 337 void vm_object_clear_flag(vm_object_t object, u_short bits);
 338 void vm_object_pip_add(vm_object_t object, short i);
 339 void vm_object_pip_wakeup(vm_object_t object);
 340 void vm_object_pip_wakeupn(vm_object_t object, short i);
 341 void vm_object_pip_wait(vm_object_t object, const char *waitid);
 342 void vm_object_pip_wait_unlocked(vm_object_t object, const char *waitid);
 343
 344 void vm_object_busy(vm_object_t object);
 345 void vm_object_unbusy(vm_object_t object);
 346 void vm_object_busy_wait(vm_object_t object, const char *wmesg);
 347
 348 static inline bool
 349 vm_object_busied(vm_object_t object)
 350 {
 351
 352         return (blockcount_read(&object->busy) != 0);
 353 }
 354 #define VM_OBJECT_ASSERT_BUSY(object)   MPASS(vm_object_busied((object)))
 355
 356 void umtx_shm_object_init(vm_object_t object);
 357 void umtx_shm_object_terminated(vm_object_t object);
 358 extern int umtx_shm_vnobj_persistent;
 359
 360 vm_object_t vm_object_allocate (objtype_t, vm_pindex_t);
 361 vm_object_t vm_object_allocate_anon(vm_pindex_t, vm_object_t, struct ucred *,
 362    vm_size_t);
 363 boolean_t vm_object_coalesce(vm_object_t, vm_ooffset_t, vm_size_t, vm_size_t,
 364    boolean_t);
 365 void vm_object_collapse (vm_object_t);
 366 void vm_object_deallocate (vm_object_t);
 367 void vm_object_destroy (vm_object_t);
 368 void vm_object_terminate (vm_object_t);
 369 void vm_object_set_writeable_dirty (vm_object_t);
 370 void vm_object_init (void);
 371 int  vm_object_kvme_type(vm_object_t object, struct vnode **vpp);
 372 void vm_object_madvise(vm_object_t, vm_pindex_t, vm_pindex_t, int);
 373 boolean_t vm_object_page_clean(vm_object_t object, vm_ooffset_t start,
 374     vm_ooffset_t end, int flags);
 375 void vm_object_page_noreuse(vm_object_t object, vm_pindex_t start,
 376     vm_pindex_t end);
 377 void vm_object_page_remove(vm_object_t object, vm_pindex_t start,
 378     vm_pindex_t end, int options);
 379 boolean_t vm_object_populate(vm_object_t, vm_pindex_t, vm_pindex_t);
 380 void vm_object_print(long addr, boolean_t have_addr, long count, char *modif);
 381 void vm_object_reference (vm_object_t);
 382 void vm_object_reference_locked(vm_object_t);
 383 int  vm_object_set_memattr(vm_object_t object, vm_memattr_t memattr);
 384 void vm_object_shadow(vm_object_t *, vm_ooffset_t *, vm_size_t, struct ucred *,
 385     bool);
 386 void vm_object_split(vm_map_entry_t);
 387 boolean_t vm_object_sync(vm_object_t, vm_ooffset_t, vm_size_t, boolean_t,
 388     boolean_t);
 389 void vm_object_unwire(vm_object_t object, vm_ooffset_t offset,
 390     vm_size_t length, uint8_t queue);
 391 struct vnode *vm_object_vnode(vm_object_t object);
 392 #endif                          /* _KERNEL */
 393
 394 #endif                          /* _VM_OBJECT_ */