xref: /xnu-11417.121.6/osfmk/vm/vm_object_xnu.h (revision a1e26a70f38d1d7daa7b49b258e2f8538ad81650)
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28 /*
29  * @OSF_COPYRIGHT@
30  */
31 /*
32  * Mach Operating System
33  * Copyright (c) 1991,1990,1989,1988,1987 Carnegie Mellon University
34  * All Rights Reserved.
35  *
36  * Permission to use, copy, modify and distribute this software and its
37  * documentation is hereby granted, provided that both the copyright
38  * notice and this permission notice appear in all copies of the
39  * software, derivative works or modified versions, and any portions
40  * thereof, and that both notices appear in supporting documentation.
41  *
42  * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
43  * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
44  * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
45  *
46  * Carnegie Mellon requests users of this software to return to
47  *
48  *  Software Distribution Coordinator  or  [email protected]
49  *  School of Computer Science
50  *  Carnegie Mellon University
51  *  Pittsburgh PA 15213-3890
52  *
53  * any improvements or extensions that they make and grant Carnegie Mellon
54  * the rights to redistribute these changes.
55  */
56 /*
57  */
58 /*
59  *	File:	vm_object_xnu.h
60  *	Author:	Avadis Tevanian, Jr., Michael Wayne Young
61  *	Date:	1985
62  *
63  *	Virtual memory object module definitions.
64  */
65 
66 #ifndef _VM_VM_OBJECT_XNU_H_
67 #define _VM_VM_OBJECT_XNU_H_
68 
69 #ifdef XNU_KERNEL_PRIVATE
70 
71 #include <kern/queue.h>
72 
73 #ifdef MACH_KERNEL_PRIVATE
74 
75 #include <debug.h>
76 #include <mach_assert.h>
77 
78 #include <mach/kern_return.h>
79 #include <mach/boolean.h>
80 #include <mach/memory_object_types.h>
81 #include <mach/port.h>
82 #include <mach/vm_prot.h>
83 #include <mach/vm_param.h>
84 #include <mach/machine/vm_types.h>
85 #include <kern/locks.h>
86 #include <kern/assert.h>
87 #include <kern/misc_protos.h>
88 #include <vm/pmap.h>
89 #include <vm/vm_external.h>
90 #include <vm/vm_options.h>
91 #include <kern/macro_help.h>
92 #include <ipc/ipc_types.h>
93 #include <vm/vm_page.h>
94 
95 
96 struct vm_page;
97 
98 /*
99  *	Types defined:
100  *
101  *	vm_object_t		Virtual memory object.
102  *	vm_object_fault_info_t	Used to determine cluster size.
103  */
104 
105 struct vm_object_fault_info {
106 	int             interruptible;
107 	uint32_t        user_tag;
108 	vm_size_t       cluster_size;
109 	vm_behavior_t   behavior;
110 	vm_object_offset_t lo_offset;
111 	vm_object_offset_t hi_offset;
112 	unsigned int
113 	/* boolean_t */ no_cache:1,
114 	/* boolean_t */ stealth:1,
115 	/* boolean_t */ io_sync:1,
116 	/* boolean_t */ cs_bypass:1,
117 	/* boolean_t */ csm_associated:1,
118 	/* boolean_t */ mark_zf_absent:1,
119 	/* boolean_t */ batch_pmap_op:1,
120 	/* boolean_t */ resilient_media:1,
121 	/* boolean_t */ no_copy_on_read:1,
122 	/* boolean_t */ fi_xnu_user_debug:1,
123 	/* boolean_t */ fi_used_for_tpro:1,
124 	/* boolean_t */ fi_change_wiring:1,
125 	/* boolean_t */ fi_no_sleep:1,
126 	__vm_object_fault_info_unused_bits:19;
127 	int             pmap_options;
128 };
129 
130 #define vo_size                         vo_un1.vou_size
131 #define vo_cache_pages_to_scan          vo_un1.vou_cache_pages_to_scan
132 #define vo_shadow_offset                vo_un2.vou_shadow_offset
133 #define vo_cache_ts                     vo_un2.vou_cache_ts
134 #define vo_owner                        vo_un2.vou_owner
135 
136 struct vm_object {
137 	/*
138 	 * on 64 bit systems we pack the pointers hung off the memq.
139 	 * those pointers have to be able to point back to the memq.
140 	 * the packed pointers are required to be on a 64 byte boundary
141 	 * which means 2 things for the vm_object...  (1) the memq
142 	 * struct has to be the first element of the structure so that
143 	 * we can control its alignment... (2) the vm_object must be
144 	 * aligned on a 64 byte boundary... for static vm_object's
145 	 * this is accomplished via the 'aligned' attribute... for
146 	 * vm_object's in the zone pool, this is accomplished by
147 	 * rounding the size of the vm_object element to the nearest
148 	 * 64 byte size before creating the zone.
149 	 */
150 	vm_page_queue_head_t    memq;           /* Resident memory - must be first */
151 	lck_rw_t                Lock;           /* Synchronization */
152 
153 	union {
154 		vm_object_size_t  vou_size;     /* Object size (only valid if internal) */
155 		int               vou_cache_pages_to_scan;      /* pages yet to be visited in an
156 		                                                 * external object in cache
157 		                                                 */
158 	} vo_un1;
159 
160 	struct vm_page          *memq_hint;
161 	os_ref_atomic_t         ref_count;        /* Number of references */
162 	unsigned int            resident_page_count;
163 	/* number of resident pages */
164 	unsigned int            wired_page_count; /* number of wired pages
165 	                                           *  use VM_OBJECT_WIRED_PAGE_UPDATE macros to update */
166 	unsigned int            reusable_page_count;
167 
168 	struct vm_object        *vo_copy;       /* Object that should receive
169 	                                         * a copy of my changed pages,
170 	                                         * for copy_delay, or just the
171 	                                         * temporary object that
172 	                                         * shadows this object, for
173 	                                         * copy_call.
174 	                                         */
175 	uint32_t                vo_copy_version;
176 	uint32_t                vo_inherit_copy_none:1,
177 	    __vo_unused_padding:31;
178 	struct vm_object        *shadow;        /* My shadow */
179 	memory_object_t         pager;          /* Where to get data */
180 
181 	union {
182 		vm_object_offset_t vou_shadow_offset;   /* Offset into shadow */
183 		clock_sec_t     vou_cache_ts;   /* age of an external object
184 		                                 * present in cache
185 		                                 */
186 		task_t          vou_owner;      /* If the object is purgeable
187 		                                 * or has a "ledger_tag", this
188 		                                 * is the task that owns it.
189 		                                 */
190 	} vo_un2;
191 
192 	vm_object_offset_t      paging_offset;  /* Offset into memory object */
193 	memory_object_control_t pager_control;  /* Where data comes back */
194 
195 	memory_object_copy_strategy_t
196 	    copy_strategy;                      /* How to handle data copy */
197 
198 	/*
199 	 * Some user processes (mostly VirtualMachine software) take a large
200 	 * number of UPLs (via IOMemoryDescriptors) to wire pages in large
201 	 * VM objects and overflow the 16-bit "activity_in_progress" counter.
202 	 * Since we never enforced any limit there, let's give them 32 bits
203 	 * for backwards compatibility's sake.
204 	 */
205 	uint16_t                paging_in_progress;
206 	uint16_t                vo_size_delta;
207 	uint32_t                activity_in_progress;
208 
209 	/* The memory object ports are
210 	 * being used (e.g., for pagein
211 	 * or pageout) -- don't change
212 	 * any of these fields (i.e.,
213 	 * don't collapse, destroy or
214 	 * terminate)
215 	 */
216 
217 	unsigned int
218 	/* boolean_t array */ all_wanted:7,     /* Bit array of "want to be
219 	                                         * awakened" notations.  See
220 	                                         * VM_OBJECT_EVENT_* items
221 	                                         * below */
222 	/* boolean_t */ pager_created:1,        /* Has pager been created? */
223 	/* boolean_t */ pager_initialized:1,    /* Are fields ready to use? */
224 	/* boolean_t */ pager_ready:1,          /* Will pager take requests? */
225 
226 	/* boolean_t */ pager_trusted:1,        /* The pager for this object
227 	                                         * is trusted. This is true for
228 	                                         * all internal objects (backed
229 	                                         * by the default pager)
230 	                                         */
231 	/* boolean_t */ can_persist:1,          /* The kernel may keep the data
232 	                                         * for this object (and rights
233 	                                         * to the memory object) after
234 	                                         * all address map references
235 	                                         * are deallocated?
236 	                                         */
237 	/* boolean_t */ internal:1,             /* Created by the kernel (and
238 	                                         * therefore, managed by the
239 	                                         * default memory manger)
240 	                                         */
241 	/* boolean_t */ private:1,              /* magic device_pager object,
242 	                                        * holds private pages only */
243 	/* boolean_t */ pageout:1,              /* pageout object. contains
244 	                                         * private pages that refer to
245 	                                         * a real memory object. */
246 	/* boolean_t */ alive:1,                /* Not yet terminated */
247 
248 	/* boolean_t */ purgable:2,             /* Purgable state.  See
249 	                                         * VM_PURGABLE_*
250 	                                         */
251 	/* boolean_t */ purgeable_only_by_kernel:1,
252 	/* boolean_t */ purgeable_when_ripe:1,         /* Purgeable when a token
253 	                                                * becomes ripe.
254 	                                                */
255 	/* boolean_t */ shadowed:1,             /* Shadow may exist */
256 	/* boolean_t */ true_share:1,
257 	/* This object is mapped
258 	 * in more than one place
259 	 * and hence cannot be
260 	 * coalesced */
261 	/* boolean_t */ terminating:1,
262 	/* Allows vm_object_lookup
263 	 * and vm_object_deallocate
264 	 * to special case their
265 	 * behavior when they are
266 	 * called as a result of
267 	 * page cleaning during
268 	 * object termination
269 	 */
270 	/* boolean_t */ named:1,                /* An enforces an internal
271 	                                         * naming convention, by
272 	                                         * calling the right routines
273 	                                         * for allocation and
274 	                                         * destruction, UBC references
275 	                                         * against the vm_object are
276 	                                         * checked.
277 	                                         */
278 	/* boolean_t */ shadow_severed:1,
279 	/* When a permanent object
280 	 * backing a COW goes away
281 	 * unexpectedly.  This bit
282 	 * allows vm_fault to return
283 	 * an error rather than a
284 	 * zero filled page.
285 	 */
286 	/* boolean_t */ phys_contiguous:1,
287 	/* Memory is wired and
288 	 * guaranteed physically
289 	 * contiguous.  However
290 	 * it is not device memory
291 	 * and obeys normal virtual
292 	 * memory rules w.r.t pmap
293 	 * access bits.
294 	 */
295 	/* boolean_t */ nophyscache:1,
296 	/* When mapped at the
297 	 * pmap level, don't allow
298 	 * primary caching. (for
299 	 * I/O)
300 	 */
301 	/* boolean_t */ for_realtime:1,
302 	/* Might be needed for realtime code path */
303 	/* vm_object_destroy_reason_t */ no_pager_reason:3,
304 	/* differentiate known and unknown causes */
305 #if FBDP_DEBUG_OBJECT_NO_PAGER
306 	/* boolean_t */ fbdp_tracked:1;
307 #else /* FBDP_DEBUG_OBJECT_NO_PAGER */
308 	__object1_unused_bits:1;
309 #endif /* FBDP_DEBUG_OBJECT_NO_PAGER */
310 
311 	queue_chain_t           cached_list;    /* Attachment point for the
312 	                                         * list of objects cached as a
313 	                                         * result of their can_persist
314 	                                         * value
315 	                                         */
316 	/*
317 	 * the following fields are not protected by any locks
318 	 * they are updated via atomic compare and swap
319 	 */
320 	vm_object_offset_t      last_alloc;     /* last allocation offset */
321 	vm_offset_t             cow_hint;       /* last page present in     */
322 	                                        /* shadow but not in object */
323 	int                     sequential;     /* sequential access size */
324 
325 	uint32_t                pages_created;
326 	uint32_t                pages_used;
327 	/* hold object lock when altering */
328 	unsigned        int
329 	    wimg_bits:8,                /* cache WIMG bits         */
330 	    code_signed:1,              /* pages are signed and should be
331 	                                 *  validated; the signatures are stored
332 	                                 *  with the pager */
333 	    transposed:1,               /* object was transposed with another */
334 	    mapping_in_progress:1,      /* pager being mapped/unmapped */
335 	    phantom_isssd:1,
336 	    volatile_empty:1,
337 	    volatile_fault:1,
338 	    all_reusable:1,
339 	    blocked_access:1,
340 	    set_cache_attr:1,
341 	    object_is_shared_cache:1,
342 	    purgeable_queue_type:2,
343 	    purgeable_queue_group:3,
344 	    io_tracking:1,
345 	    no_tag_update:1,            /*  */
346 #if CONFIG_SECLUDED_MEMORY
347 	    eligible_for_secluded:1,
348 	    can_grab_secluded:1,
349 #else /* CONFIG_SECLUDED_MEMORY */
350 	__object3_unused_bits:2,
351 #endif /* CONFIG_SECLUDED_MEMORY */
352 #if VM_OBJECT_ACCESS_TRACKING
353 	    access_tracking:1,
354 #else /* VM_OBJECT_ACCESS_TRACKING */
355 	__unused_access_tracking:1,
356 #endif /* VM_OBJECT_ACCESS_TRACKING */
357 	vo_ledger_tag:3,
358 	    vo_no_footprint:1;
359 
360 #if VM_OBJECT_ACCESS_TRACKING
361 	uint32_t        access_tracking_reads;
362 	uint32_t        access_tracking_writes;
363 #endif /* VM_OBJECT_ACCESS_TRACKING */
364 
365 	uint8_t                 scan_collisions;
366 	uint8_t                 __object4_unused_bits[1];
367 	vm_tag_t                wire_tag;
368 
369 #if CONFIG_PHANTOM_CACHE
370 	uint32_t                phantom_object_id;
371 #endif
372 #if CONFIG_IOSCHED || UPL_DEBUG
373 	queue_head_t            uplq;           /* List of outstanding upls */
374 #endif
375 
376 #ifdef  VM_PIP_DEBUG
377 /*
378  * Keep track of the stack traces for the first holders
379  * of a "paging_in_progress" reference for this VM object.
380  */
381 #define VM_PIP_DEBUG_STACK_FRAMES       25      /* depth of each stack trace */
382 #define VM_PIP_DEBUG_MAX_REFS           10      /* track that many references */
383 	struct __pip_backtrace {
384 		void *pip_retaddr[VM_PIP_DEBUG_STACK_FRAMES];
385 	} pip_holders[VM_PIP_DEBUG_MAX_REFS];
386 #endif  /* VM_PIP_DEBUG  */
387 
388 	queue_chain_t           objq;      /* object queue - currently used for purgable queues */
389 	queue_chain_t           task_objq; /* objects owned by task - protected by task lock */
390 
391 #if !VM_TAG_ACTIVE_UPDATE
392 	queue_chain_t           wired_objq;
393 #endif /* !VM_TAG_ACTIVE_UPDATE */
394 
395 #if DEBUG
396 	void *purgeable_owner_bt[16];
397 	task_t vo_purgeable_volatilizer; /* who made it volatile? */
398 	void *purgeable_volatilizer_bt[16];
399 #endif /* DEBUG */
400 
401 	/*
402 	 * If this object is backed by anonymous memory, this represents the ID of
403 	 * the vm_map that the memory originated from (i.e. this points backwards in
404 	 * shadow chains). Note that an originator is present even if the object
405 	 * hasn't been faulted into the backing pmap yet.
406 	 */
407 	vm_map_serial_t vmo_provenance;
408 };
409 
410 #define VM_OBJECT_PURGEABLE_FAULT_ERROR(object)                         \
411 	((object)->volatile_fault &&                                    \
412 	 ((object)->purgable == VM_PURGABLE_VOLATILE ||                 \
413 	  (object)->purgable == VM_PURGABLE_EMPTY))
414 
415 extern const vm_object_t kernel_object_default;  /* the default kernel object */
416 
417 extern const vm_object_t compressor_object;      /* the single compressor object, allocates pages for compressed
418                                                   * buffers (not the segments) */
419 
420 extern const vm_object_t retired_pages_object;   /* pages retired due to ECC, should never be used */
421 
422 
423 #define is_kernel_object(object) ((object) == kernel_object_default)
424 
425 
426 extern const vm_object_t exclaves_object;        /* holds VM pages owned by exclaves */
427 
428 # define        VM_MSYNC_INITIALIZED                    0
429 # define        VM_MSYNC_SYNCHRONIZING                  1
430 # define        VM_MSYNC_DONE                           2
431 
432 
433 extern lck_grp_t                vm_map_lck_grp;
434 extern lck_attr_t               vm_map_lck_attr;
435 
436 /** os_refgrp_t for vm_objects */
437 os_refgrp_decl_extern(vm_object_refgrp);
438 
439 #ifndef VM_TAG_ACTIVE_UPDATE
440 #error VM_TAG_ACTIVE_UPDATE
441 #endif
442 
443 #if VM_TAG_ACTIVE_UPDATE
444 #define VM_OBJECT_WIRED_ENQUEUE(object) panic("VM_OBJECT_WIRED_ENQUEUE")
445 #define VM_OBJECT_WIRED_DEQUEUE(object) panic("VM_OBJECT_WIRED_DEQUEUE")
446 #else /* VM_TAG_ACTIVE_UPDATE */
447 #define VM_OBJECT_WIRED_ENQUEUE(object)                                 \
448 	MACRO_BEGIN                                                     \
449 	lck_spin_lock_grp(&vm_objects_wired_lock, &vm_page_lck_grp_bucket);                          \
450 	assert(!(object)->wired_objq.next);                             \
451 	assert(!(object)->wired_objq.prev);                             \
452 	queue_enter(&vm_objects_wired, (object),                        \
453 	            vm_object_t, wired_objq);                           \
454 	lck_spin_unlock(&vm_objects_wired_lock);                        \
455 	MACRO_END
456 #define VM_OBJECT_WIRED_DEQUEUE(object)                                 \
457 	MACRO_BEGIN                                                     \
458 	if ((object)->wired_objq.next) {                                \
459 	        lck_spin_lock_grp(&vm_objects_wired_lock, &vm_page_lck_grp_bucket);                  \
460 	        queue_remove(&vm_objects_wired, (object),               \
461 	                     vm_object_t, wired_objq);                  \
462 	        lck_spin_unlock(&vm_objects_wired_lock);                \
463 	}                                                               \
464 	MACRO_END
465 #endif /* VM_TAG_ACTIVE_UPDATE */
466 
467 #define VM_OBJECT_WIRED(object, tag)                                    \
468     MACRO_BEGIN                                                         \
469     assert(VM_KERN_MEMORY_NONE != (tag));                               \
470     assert(VM_KERN_MEMORY_NONE == (object)->wire_tag);                  \
471     (object)->wire_tag = (tag);                                         \
472     if (!VM_TAG_ACTIVE_UPDATE) {                                        \
473 	VM_OBJECT_WIRED_ENQUEUE((object));                              \
474     }                                                                   \
475     MACRO_END
476 
477 #define VM_OBJECT_UNWIRED(object)                                                       \
478     MACRO_BEGIN                                                                         \
479     if (!VM_TAG_ACTIVE_UPDATE) {                                                        \
480 	    VM_OBJECT_WIRED_DEQUEUE((object));                                          \
481     }                                                                                   \
482     if (VM_KERN_MEMORY_NONE != (object)->wire_tag) {                                    \
483 	vm_tag_update_size((object)->wire_tag, -ptoa_64((object)->wired_page_count), (object));   \
484 	(object)->wire_tag = VM_KERN_MEMORY_NONE;                                       \
485     }                                                                                   \
486     MACRO_END
487 
488 // These two macros start & end a C block
489 #define VM_OBJECT_WIRED_PAGE_UPDATE_START(object)                                       \
490     MACRO_BEGIN                                                                         \
491     {                                                                                   \
492 	int64_t __wireddelta = 0; vm_tag_t __waswired = (object)->wire_tag;
493 
494 #define VM_OBJECT_WIRED_PAGE_UPDATE_END(object, tag)                                    \
495 	if (__wireddelta) {                                                             \
496 	    boolean_t __overflow __assert_only =                                        \
497 	    os_add_overflow((object)->wired_page_count, __wireddelta,                   \
498 	                    &(object)->wired_page_count);                               \
499 	    assert(!__overflow);                                                        \
500 	    if (!(object)->internal &&                                  \
501 	        (object)->vo_ledger_tag &&                              \
502 	        VM_OBJECT_OWNER((object)) != NULL) {                    \
503 	            vm_object_wired_page_update_ledgers(object, __wireddelta); \
504 	    }                                                           \
505 	    if (!(object)->pageout && !(object)->no_tag_update) {                       \
506 	        if (__wireddelta > 0) {                                                 \
507 	            assert (VM_KERN_MEMORY_NONE != (tag));                              \
508 	            if (VM_KERN_MEMORY_NONE == __waswired) {                            \
509 	                VM_OBJECT_WIRED((object), (tag));                               \
510 	            }                                                                   \
511 	            vm_tag_update_size((object)->wire_tag, ptoa_64(__wireddelta), (object));      \
512 	        } else if (VM_KERN_MEMORY_NONE != __waswired) {                         \
513 	            assert (VM_KERN_MEMORY_NONE != (object)->wire_tag);                 \
514 	            vm_tag_update_size((object)->wire_tag, ptoa_64(__wireddelta), (object));      \
515 	            if (!(object)->wired_page_count) {                                  \
516 	                VM_OBJECT_UNWIRED((object));                                    \
517 	            }                                                                   \
518 	        }                                                                       \
519 	    }                                                                           \
520 	}                                                                               \
521     }                                                                                   \
522     MACRO_END
523 
524 #define VM_OBJECT_WIRED_PAGE_COUNT(object, delta)               \
525     __wireddelta += delta; \
526 
527 #define VM_OBJECT_WIRED_PAGE_ADD(object, m)                     \
528     if (vm_page_is_canonical(m)) __wireddelta++;
529 
530 #define VM_OBJECT_WIRED_PAGE_REMOVE(object, m)                  \
531     if (vm_page_is_canonical(m)) __wireddelta--;
532 
533 #define OBJECT_LOCK_SHARED      0
534 #define OBJECT_LOCK_EXCLUSIVE   1
535 
536 extern lck_grp_t        vm_object_lck_grp;
537 extern lck_attr_t       vm_object_lck_attr;
538 extern lck_attr_t       kernel_object_lck_attr;
539 extern lck_attr_t       compressor_object_lck_attr;
540 
541 extern vm_object_t      vm_pageout_scan_wants_object;
542 
543 extern void             vm_object_lock(vm_object_t);
544 extern bool             vm_object_lock_check_contended(vm_object_t);
545 extern boolean_t        vm_object_lock_try(vm_object_t);
546 extern boolean_t        _vm_object_lock_try(vm_object_t);
547 extern boolean_t        vm_object_lock_avoid(vm_object_t);
548 extern void             vm_object_lock_shared(vm_object_t);
549 extern boolean_t        vm_object_lock_yield_shared(vm_object_t);
550 extern boolean_t        vm_object_lock_try_shared(vm_object_t);
551 extern void             vm_object_unlock(vm_object_t);
552 extern boolean_t        vm_object_lock_upgrade(vm_object_t);
553 
554 extern void             kdp_vm_object_sleep_find_owner(
555 	event64_t          wait_event,
556 	block_hint_t       wait_type,
557 	thread_waitinfo_t *waitinfo);
558 
559 #endif /* MACH_KERNEL_PRIVATE */
560 
561 #if CONFIG_IOSCHED
562 struct io_reprioritize_req {
563 	uint64_t        blkno;
564 	uint32_t        len;
565 	int             priority;
566 	struct vnode    *devvp;
567 	struct mpsc_queue_chain iorr_elm;
568 };
569 typedef struct io_reprioritize_req *io_reprioritize_req_t;
570 
571 extern void vm_io_reprioritize_init(void);
572 #endif
573 
574 extern void page_worker_init(void);
575 
576 
577 #endif /* XNU_KERNEL_PRIVATE */
578 
579 #endif  /* _VM_VM_OBJECT_XNU_H_ */
580