xref: /xnu-8796.101.5/osfmk/vm/bsd_vm.c (revision aca3beaa3dfbd42498b42c5e5ce20a938e6554e5)
1 /*
2  * Copyright (c) 2000-2020 Apple Inc. All rights reserved.
3  *
4  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
5  *
6  * This file contains Original Code and/or Modifications of Original Code
7  * as defined in and that are subject to the Apple Public Source License
8  * Version 2.0 (the 'License'). You may not use this file except in
9  * compliance with the License. The rights granted to you under the License
10  * may not be used to create, or enable the creation or redistribution of,
11  * unlawful or unlicensed copies of an Apple operating system, or to
12  * circumvent, violate, or enable the circumvention or violation of, any
13  * terms of an Apple operating system software license agreement.
14  *
15  * Please obtain a copy of the License at
16  * http://www.opensource.apple.com/apsl/ and read it before using this file.
17  *
18  * The Original Code and all software distributed under the License are
19  * distributed on an 'AS IS' basis, WITHOUT WARRANTY OF ANY KIND, EITHER
20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
21  * INCLUDING WITHOUT LIMITATION, ANY WARRANTIES OF MERCHANTABILITY,
22  * FITNESS FOR A PARTICULAR PURPOSE, QUIET ENJOYMENT OR NON-INFRINGEMENT.
23  * Please see the License for the specific language governing rights and
24  * limitations under the License.
25  *
26  * @APPLE_OSREFERENCE_LICENSE_HEADER_END@
27  */
28 
29 #include <sys/errno.h>
30 
31 #include <mach/mach_types.h>
32 #include <mach/mach_traps.h>
33 #include <mach/host_priv.h>
34 #include <mach/kern_return.h>
35 #include <mach/memory_object_control.h>
36 #include <mach/memory_object_types.h>
37 #include <mach/port.h>
38 #include <mach/policy.h>
39 #include <mach/upl.h>
40 #include <mach/thread_act.h>
41 
42 #include <kern/assert.h>
43 #include <kern/host.h>
44 #include <kern/ledger.h>
45 #include <kern/thread.h>
46 #include <kern/ipc_kobject.h>
47 #include <os/refcnt.h>
48 
49 #include <ipc/ipc_port.h>
50 #include <ipc/ipc_space.h>
51 
52 #include <vm/vm_map.h>
53 #include <vm/vm_pageout.h>
54 #include <vm/memory_object.h>
55 #include <vm/vm_pageout.h>
56 #include <vm/vm_protos.h>
57 #include <vm/vm_purgeable_internal.h>
58 
59 #include <sys/kdebug_triage.h>
60 
61 /* BSD VM COMPONENT INTERFACES */
62 int
63 get_map_nentries(
64 	vm_map_t);
65 
66 int
get_map_nentries(vm_map_t map)67 get_map_nentries(
68 	vm_map_t map)
69 {
70 	return map->hdr.nentries;
71 }
72 
73 /*
74  * BSD VNODE PAGER
75  */
76 
77 const struct memory_object_pager_ops vnode_pager_ops = {
78 	.memory_object_reference = vnode_pager_reference,
79 	.memory_object_deallocate = vnode_pager_deallocate,
80 	.memory_object_init = vnode_pager_init,
81 	.memory_object_terminate = vnode_pager_terminate,
82 	.memory_object_data_request = vnode_pager_data_request,
83 	.memory_object_data_return = vnode_pager_data_return,
84 	.memory_object_data_initialize = vnode_pager_data_initialize,
85 	.memory_object_map = vnode_pager_map,
86 	.memory_object_last_unmap = vnode_pager_last_unmap,
87 	.memory_object_backing_object = NULL,
88 	.memory_object_pager_name = "vnode pager"
89 };
90 
91 typedef struct vnode_pager {
92 	/* mandatory generic header */
93 	struct memory_object vn_pgr_hdr;
94 
95 	/*  pager-specific */
96 #if MEMORY_OBJECT_HAS_REFCOUNT
97 #define vn_pgr_hdr_ref      vn_pgr_hdr.mo_ref
98 #else
99 	os_ref_atomic_t         vn_pgr_hdr_ref;
100 #endif
101 	struct vnode            *vnode_handle;  /* vnode handle              */
102 } *vnode_pager_t;
103 
104 
105 kern_return_t
106 vnode_pager_cluster_read(               /* forward */
107 	vnode_pager_t,
108 	vm_object_offset_t,
109 	vm_object_offset_t,
110 	uint32_t,
111 	vm_size_t);
112 
113 void
114 vnode_pager_cluster_write(              /* forward */
115 	vnode_pager_t,
116 	vm_object_offset_t,
117 	vm_size_t,
118 	vm_object_offset_t *,
119 	int *,
120 	int);
121 
122 
123 vnode_pager_t
124 vnode_object_create(                    /* forward */
125 	struct vnode *);
126 
127 vnode_pager_t
128 vnode_pager_lookup(                     /* forward */
129 	memory_object_t);
130 
131 struct vnode *
132 vnode_pager_lookup_vnode(               /* forward */
133 	memory_object_t);
134 
135 ZONE_DEFINE_TYPE(vnode_pager_zone, "vnode pager structures",
136     struct vnode_pager, ZC_NOENCRYPT);
137 
138 #define VNODE_PAGER_NULL        ((vnode_pager_t) 0)
139 
140 /* TODO: Should be set dynamically by vnode_pager_init() */
141 #define CLUSTER_SHIFT   1
142 
143 
144 #if DEBUG
145 int pagerdebug = 0;
146 
147 #define PAGER_ALL               0xffffffff
148 #define PAGER_INIT              0x00000001
149 #define PAGER_PAGEIN    0x00000002
150 
151 #define PAGER_DEBUG(LEVEL, A) {if ((pagerdebug & LEVEL)==LEVEL){printf A;}}
152 #else
153 #define PAGER_DEBUG(LEVEL, A)
154 #endif
155 
156 extern int proc_resetpcontrol(int);
157 
158 
159 extern int      uiomove64(addr64_t, int, void *);
160 #define MAX_RUN 32
161 
162 int
memory_object_control_uiomove(memory_object_control_t control,memory_object_offset_t offset,void * uio,int start_offset,int io_requested,int mark_dirty,int take_reference)163 memory_object_control_uiomove(
164 	memory_object_control_t control,
165 	memory_object_offset_t  offset,
166 	void            *       uio,
167 	int                     start_offset,
168 	int                     io_requested,
169 	int                     mark_dirty,
170 	int                     take_reference)
171 {
172 	vm_object_t             object;
173 	vm_page_t               dst_page;
174 	int                     xsize;
175 	int                     retval = 0;
176 	int                     cur_run;
177 	int                     cur_needed;
178 	int                     i;
179 	int                     orig_offset;
180 	vm_page_t               page_run[MAX_RUN];
181 	int                     dirty_count;    /* keeps track of number of pages dirtied as part of this uiomove */
182 
183 	object = memory_object_control_to_vm_object(control);
184 	if (object == VM_OBJECT_NULL) {
185 		return 0;
186 	}
187 	assert(!object->internal);
188 
189 	vm_object_lock(object);
190 
191 	if (mark_dirty && object->copy != VM_OBJECT_NULL) {
192 		/*
193 		 * We can't modify the pages without honoring
194 		 * copy-on-write obligations first, so fall off
195 		 * this optimized path and fall back to the regular
196 		 * path.
197 		 */
198 		vm_object_unlock(object);
199 		return 0;
200 	}
201 	orig_offset = start_offset;
202 
203 	dirty_count = 0;
204 	while (io_requested && retval == 0) {
205 		cur_needed = (start_offset + io_requested + (PAGE_SIZE - 1)) / PAGE_SIZE;
206 
207 		if (cur_needed > MAX_RUN) {
208 			cur_needed = MAX_RUN;
209 		}
210 
211 		for (cur_run = 0; cur_run < cur_needed;) {
212 			if ((dst_page = vm_page_lookup(object, offset)) == VM_PAGE_NULL) {
213 				break;
214 			}
215 
216 
217 			if (dst_page->vmp_busy || dst_page->vmp_cleaning) {
218 				/*
219 				 * someone else is playing with the page... if we've
220 				 * already collected pages into this run, go ahead
221 				 * and process now, we can't block on this
222 				 * page while holding other pages in the BUSY state
223 				 * otherwise we will wait
224 				 */
225 				if (cur_run) {
226 					break;
227 				}
228 				PAGE_SLEEP(object, dst_page, THREAD_UNINT);
229 				continue;
230 			}
231 			if (dst_page->vmp_laundry) {
232 				vm_pageout_steal_laundry(dst_page, FALSE);
233 			}
234 
235 			if (mark_dirty) {
236 				if (dst_page->vmp_dirty == FALSE) {
237 					dirty_count++;
238 				}
239 				SET_PAGE_DIRTY(dst_page, FALSE);
240 				if (dst_page->vmp_cs_validated &&
241 				    !dst_page->vmp_cs_tainted) {
242 					/*
243 					 * CODE SIGNING:
244 					 * We're modifying a code-signed
245 					 * page: force revalidate
246 					 */
247 					dst_page->vmp_cs_validated = VMP_CS_ALL_FALSE;
248 
249 					VM_PAGEOUT_DEBUG(vm_cs_validated_resets, 1);
250 
251 					pmap_disconnect(VM_PAGE_GET_PHYS_PAGE(dst_page));
252 				}
253 			}
254 			dst_page->vmp_busy = TRUE;
255 
256 			page_run[cur_run++] = dst_page;
257 
258 			offset += PAGE_SIZE_64;
259 		}
260 		if (cur_run == 0) {
261 			/*
262 			 * we hit a 'hole' in the cache or
263 			 * a page we don't want to try to handle,
264 			 * so bail at this point
265 			 * we'll unlock the object below
266 			 */
267 			break;
268 		}
269 		vm_object_unlock(object);
270 
271 		for (i = 0; i < cur_run; i++) {
272 			dst_page = page_run[i];
273 
274 			if ((xsize = PAGE_SIZE - start_offset) > io_requested) {
275 				xsize = io_requested;
276 			}
277 
278 			if ((retval = uiomove64((addr64_t)(((addr64_t)(VM_PAGE_GET_PHYS_PAGE(dst_page)) << PAGE_SHIFT) + start_offset), xsize, uio))) {
279 				break;
280 			}
281 
282 			io_requested -= xsize;
283 			start_offset = 0;
284 		}
285 		vm_object_lock(object);
286 
287 		/*
288 		 * if we have more than 1 page to work on
289 		 * in the current run, or the original request
290 		 * started at offset 0 of the page, or we're
291 		 * processing multiple batches, we will move
292 		 * the pages to the tail of the inactive queue
293 		 * to implement an LRU for read/write accesses
294 		 *
295 		 * the check for orig_offset == 0 is there to
296 		 * mitigate the cost of small (< page_size) requests
297 		 * to the same page (this way we only move it once)
298 		 */
299 		if (take_reference && (cur_run > 1 || orig_offset == 0)) {
300 			vm_page_lockspin_queues();
301 
302 			for (i = 0; i < cur_run; i++) {
303 				vm_page_lru(page_run[i]);
304 			}
305 
306 			vm_page_unlock_queues();
307 		}
308 		for (i = 0; i < cur_run; i++) {
309 			dst_page = page_run[i];
310 
311 			/*
312 			 * someone is explicitly referencing this page...
313 			 * update clustered and speculative state
314 			 *
315 			 */
316 			if (dst_page->vmp_clustered) {
317 				VM_PAGE_CONSUME_CLUSTERED(dst_page);
318 			}
319 
320 			PAGE_WAKEUP_DONE(dst_page);
321 		}
322 		orig_offset = 0;
323 	}
324 	if (object->pager) {
325 		task_update_logical_writes(current_task(), (dirty_count * PAGE_SIZE), TASK_WRITE_DEFERRED, vnode_pager_lookup_vnode(object->pager));
326 	}
327 	vm_object_unlock(object);
328 	return retval;
329 }
330 
331 
332 /*
333  *
334  */
335 memory_object_t
vnode_pager_setup(struct vnode * vp,__unused memory_object_t pager)336 vnode_pager_setup(
337 	struct vnode    *vp,
338 	__unused memory_object_t        pager)
339 {
340 	vnode_pager_t   vnode_object;
341 
342 	vnode_object = vnode_object_create(vp);
343 	if (vnode_object == VNODE_PAGER_NULL) {
344 		panic("vnode_pager_setup: vnode_object_create() failed");
345 	}
346 	return (memory_object_t)vnode_object;
347 }
348 
349 /*
350  *
351  */
352 kern_return_t
vnode_pager_init(memory_object_t mem_obj,memory_object_control_t control,__unused memory_object_cluster_size_t pg_size)353 vnode_pager_init(memory_object_t mem_obj,
354     memory_object_control_t control,
355 #if !DEBUG
356     __unused
357 #endif
358     memory_object_cluster_size_t pg_size)
359 {
360 	vnode_pager_t   vnode_object;
361 	kern_return_t   kr;
362 	memory_object_attr_info_data_t  attributes;
363 
364 
365 	PAGER_DEBUG(PAGER_ALL, ("vnode_pager_init: %p, %p, %lx\n", mem_obj, control, (unsigned long)pg_size));
366 
367 	if (control == MEMORY_OBJECT_CONTROL_NULL) {
368 		return KERN_INVALID_ARGUMENT;
369 	}
370 
371 	vnode_object = vnode_pager_lookup(mem_obj);
372 
373 	memory_object_control_reference(control);
374 
375 	vnode_object->vn_pgr_hdr.mo_control = control;
376 
377 	attributes.copy_strategy = MEMORY_OBJECT_COPY_DELAY;
378 	/* attributes.cluster_size = (1 << (CLUSTER_SHIFT + PAGE_SHIFT));*/
379 	attributes.cluster_size = (1 << (PAGE_SHIFT));
380 	attributes.may_cache_object = TRUE;
381 	attributes.temporary = TRUE;
382 
383 	kr = memory_object_change_attributes(
384 		control,
385 		MEMORY_OBJECT_ATTRIBUTE_INFO,
386 		(memory_object_info_t) &attributes,
387 		MEMORY_OBJECT_ATTR_INFO_COUNT);
388 	if (kr != KERN_SUCCESS) {
389 		panic("vnode_pager_init: memory_object_change_attributes() failed");
390 	}
391 
392 	return KERN_SUCCESS;
393 }
394 
395 /*
396  *
397  */
398 kern_return_t
vnode_pager_data_return(memory_object_t mem_obj,memory_object_offset_t offset,memory_object_cluster_size_t data_cnt,memory_object_offset_t * resid_offset,int * io_error,__unused boolean_t dirty,__unused boolean_t kernel_copy,int upl_flags)399 vnode_pager_data_return(
400 	memory_object_t         mem_obj,
401 	memory_object_offset_t  offset,
402 	memory_object_cluster_size_t            data_cnt,
403 	memory_object_offset_t  *resid_offset,
404 	int                     *io_error,
405 	__unused boolean_t              dirty,
406 	__unused boolean_t              kernel_copy,
407 	int                     upl_flags)
408 {
409 	vnode_pager_t   vnode_object;
410 
411 	assertf(page_aligned(offset), "offset 0x%llx\n", offset);
412 
413 	vnode_object = vnode_pager_lookup(mem_obj);
414 
415 	vnode_pager_cluster_write(vnode_object, offset, data_cnt, resid_offset, io_error, upl_flags);
416 
417 	return KERN_SUCCESS;
418 }
419 
420 kern_return_t
vnode_pager_data_initialize(__unused memory_object_t mem_obj,__unused memory_object_offset_t offset,__unused memory_object_cluster_size_t data_cnt)421 vnode_pager_data_initialize(
422 	__unused memory_object_t                mem_obj,
423 	__unused memory_object_offset_t offset,
424 	__unused memory_object_cluster_size_t           data_cnt)
425 {
426 	panic("vnode_pager_data_initialize");
427 	return KERN_FAILURE;
428 }
429 
430 void
vnode_pager_dirtied(memory_object_t mem_obj,vm_object_offset_t s_offset,vm_object_offset_t e_offset)431 vnode_pager_dirtied(
432 	memory_object_t         mem_obj,
433 	vm_object_offset_t      s_offset,
434 	vm_object_offset_t      e_offset)
435 {
436 	vnode_pager_t   vnode_object;
437 
438 	if (mem_obj && mem_obj->mo_pager_ops == &vnode_pager_ops) {
439 		vnode_object = vnode_pager_lookup(mem_obj);
440 		vnode_pager_was_dirtied(vnode_object->vnode_handle, s_offset, e_offset);
441 	}
442 }
443 
444 kern_return_t
vnode_pager_get_isinuse(memory_object_t mem_obj,uint32_t * isinuse)445 vnode_pager_get_isinuse(
446 	memory_object_t         mem_obj,
447 	uint32_t                *isinuse)
448 {
449 	vnode_pager_t   vnode_object;
450 
451 	if (mem_obj->mo_pager_ops != &vnode_pager_ops) {
452 		*isinuse = 1;
453 		return KERN_INVALID_ARGUMENT;
454 	}
455 
456 	vnode_object = vnode_pager_lookup(mem_obj);
457 
458 	*isinuse = vnode_pager_isinuse(vnode_object->vnode_handle);
459 	return KERN_SUCCESS;
460 }
461 
462 kern_return_t
vnode_pager_get_throttle_io_limit(memory_object_t mem_obj,uint32_t * limit)463 vnode_pager_get_throttle_io_limit(
464 	memory_object_t         mem_obj,
465 	uint32_t                *limit)
466 {
467 	vnode_pager_t   vnode_object;
468 
469 	if (mem_obj->mo_pager_ops != &vnode_pager_ops) {
470 		return KERN_INVALID_ARGUMENT;
471 	}
472 
473 	vnode_object = vnode_pager_lookup(mem_obj);
474 
475 	(void)vnode_pager_return_throttle_io_limit(vnode_object->vnode_handle, limit);
476 	return KERN_SUCCESS;
477 }
478 
479 kern_return_t
vnode_pager_get_isSSD(memory_object_t mem_obj,boolean_t * isSSD)480 vnode_pager_get_isSSD(
481 	memory_object_t         mem_obj,
482 	boolean_t               *isSSD)
483 {
484 	vnode_pager_t   vnode_object;
485 
486 	if (mem_obj->mo_pager_ops != &vnode_pager_ops) {
487 		return KERN_INVALID_ARGUMENT;
488 	}
489 
490 	vnode_object = vnode_pager_lookup(mem_obj);
491 
492 	*isSSD = vnode_pager_isSSD(vnode_object->vnode_handle);
493 	return KERN_SUCCESS;
494 }
495 
496 kern_return_t
vnode_pager_get_object_size(memory_object_t mem_obj,memory_object_offset_t * length)497 vnode_pager_get_object_size(
498 	memory_object_t         mem_obj,
499 	memory_object_offset_t  *length)
500 {
501 	vnode_pager_t   vnode_object;
502 
503 	if (mem_obj->mo_pager_ops != &vnode_pager_ops) {
504 		*length = 0;
505 		return KERN_INVALID_ARGUMENT;
506 	}
507 
508 	vnode_object = vnode_pager_lookup(mem_obj);
509 
510 	*length = vnode_pager_get_filesize(vnode_object->vnode_handle);
511 	return KERN_SUCCESS;
512 }
513 
514 kern_return_t
vnode_pager_get_object_name(memory_object_t mem_obj,char * pathname,vm_size_t pathname_len,char * filename,vm_size_t filename_len,boolean_t * truncated_path_p)515 vnode_pager_get_object_name(
516 	memory_object_t         mem_obj,
517 	char                    *pathname,
518 	vm_size_t               pathname_len,
519 	char                    *filename,
520 	vm_size_t               filename_len,
521 	boolean_t               *truncated_path_p)
522 {
523 	vnode_pager_t   vnode_object;
524 
525 	if (mem_obj->mo_pager_ops != &vnode_pager_ops) {
526 		return KERN_INVALID_ARGUMENT;
527 	}
528 
529 	vnode_object = vnode_pager_lookup(mem_obj);
530 
531 	return vnode_pager_get_name(vnode_object->vnode_handle,
532 	           pathname,
533 	           pathname_len,
534 	           filename,
535 	           filename_len,
536 	           truncated_path_p);
537 }
538 
539 kern_return_t
vnode_pager_get_object_mtime(memory_object_t mem_obj,struct timespec * mtime,struct timespec * cs_mtime)540 vnode_pager_get_object_mtime(
541 	memory_object_t         mem_obj,
542 	struct timespec         *mtime,
543 	struct timespec         *cs_mtime)
544 {
545 	vnode_pager_t   vnode_object;
546 
547 	if (mem_obj->mo_pager_ops != &vnode_pager_ops) {
548 		return KERN_INVALID_ARGUMENT;
549 	}
550 
551 	vnode_object = vnode_pager_lookup(mem_obj);
552 
553 	return vnode_pager_get_mtime(vnode_object->vnode_handle,
554 	           mtime,
555 	           cs_mtime);
556 }
557 
558 #if CHECK_CS_VALIDATION_BITMAP
559 kern_return_t
vnode_pager_cs_check_validation_bitmap(memory_object_t mem_obj,memory_object_offset_t offset,int optype)560 vnode_pager_cs_check_validation_bitmap(
561 	memory_object_t mem_obj,
562 	memory_object_offset_t  offset,
563 	int             optype  )
564 {
565 	vnode_pager_t   vnode_object;
566 
567 	if (mem_obj == MEMORY_OBJECT_NULL ||
568 	    mem_obj->mo_pager_ops != &vnode_pager_ops) {
569 		return KERN_INVALID_ARGUMENT;
570 	}
571 
572 	vnode_object = vnode_pager_lookup(mem_obj);
573 	return ubc_cs_check_validation_bitmap( vnode_object->vnode_handle, offset, optype );
574 }
575 #endif /* CHECK_CS_VALIDATION_BITMAP */
576 
577 /*
578  *
579  */
580 kern_return_t
vnode_pager_data_request(memory_object_t mem_obj,memory_object_offset_t offset,__unused memory_object_cluster_size_t length,__unused vm_prot_t desired_access,memory_object_fault_info_t fault_info)581 vnode_pager_data_request(
582 	memory_object_t         mem_obj,
583 	memory_object_offset_t  offset,
584 	__unused memory_object_cluster_size_t   length,
585 	__unused vm_prot_t      desired_access,
586 	memory_object_fault_info_t      fault_info)
587 {
588 	vnode_pager_t           vnode_object;
589 	memory_object_offset_t  base_offset;
590 	vm_size_t               size;
591 	uint32_t                io_streaming = 0;
592 
593 	assertf(page_aligned(offset), "offset 0x%llx\n", offset);
594 
595 	vnode_object = vnode_pager_lookup(mem_obj);
596 
597 	size = MAX_UPL_TRANSFER_BYTES;
598 	base_offset = offset;
599 
600 	if (memory_object_cluster_size(vnode_object->vn_pgr_hdr.mo_control,
601 	    &base_offset, &size, &io_streaming,
602 	    fault_info) != KERN_SUCCESS) {
603 		size = PAGE_SIZE;
604 	}
605 
606 	assert(offset >= base_offset &&
607 	    offset < base_offset + size);
608 
609 	return vnode_pager_cluster_read(vnode_object, base_offset, offset, io_streaming, size);
610 }
611 
612 /*
613  *
614  */
615 void
vnode_pager_reference(memory_object_t mem_obj)616 vnode_pager_reference(
617 	memory_object_t         mem_obj)
618 {
619 	vnode_pager_t   vnode_object;
620 
621 	vnode_object = vnode_pager_lookup(mem_obj);
622 	os_ref_retain_raw(&vnode_object->vn_pgr_hdr_ref, NULL);
623 }
624 
625 /*
626  *
627  */
628 void
vnode_pager_deallocate(memory_object_t mem_obj)629 vnode_pager_deallocate(
630 	memory_object_t         mem_obj)
631 {
632 	vnode_pager_t   vnode_object;
633 
634 	PAGER_DEBUG(PAGER_ALL, ("vnode_pager_deallocate: %p\n", mem_obj));
635 
636 	vnode_object = vnode_pager_lookup(mem_obj);
637 
638 	if (os_ref_release_raw(&vnode_object->vn_pgr_hdr_ref, NULL) == 0) {
639 		if (vnode_object->vnode_handle != NULL) {
640 			vnode_pager_vrele(vnode_object->vnode_handle);
641 		}
642 		zfree(vnode_pager_zone, vnode_object);
643 	}
644 }
645 
646 /*
647  *
648  */
649 kern_return_t
vnode_pager_terminate(__unused memory_object_t mem_obj)650 vnode_pager_terminate(
651 #if !DEBUG
652 	__unused
653 #endif
654 	memory_object_t mem_obj)
655 {
656 	PAGER_DEBUG(PAGER_ALL, ("vnode_pager_terminate: %p\n", mem_obj));
657 
658 	return KERN_SUCCESS;
659 }
660 
661 /*
662  *
663  */
664 kern_return_t
vnode_pager_map(memory_object_t mem_obj,vm_prot_t prot)665 vnode_pager_map(
666 	memory_object_t         mem_obj,
667 	vm_prot_t               prot)
668 {
669 	vnode_pager_t           vnode_object;
670 	int                     ret;
671 	kern_return_t           kr;
672 
673 	PAGER_DEBUG(PAGER_ALL, ("vnode_pager_map: %p %x\n", mem_obj, prot));
674 
675 	vnode_object = vnode_pager_lookup(mem_obj);
676 
677 	ret = ubc_map(vnode_object->vnode_handle, prot);
678 
679 	if (ret != 0) {
680 		kr = KERN_FAILURE;
681 	} else {
682 		kr = KERN_SUCCESS;
683 	}
684 
685 	return kr;
686 }
687 
688 kern_return_t
vnode_pager_last_unmap(memory_object_t mem_obj)689 vnode_pager_last_unmap(
690 	memory_object_t         mem_obj)
691 {
692 	vnode_pager_t   vnode_object;
693 
694 	PAGER_DEBUG(PAGER_ALL, ("vnode_pager_last_unmap: %p\n", mem_obj));
695 
696 	vnode_object = vnode_pager_lookup(mem_obj);
697 
698 	ubc_unmap(vnode_object->vnode_handle);
699 	return KERN_SUCCESS;
700 }
701 
702 
703 
704 /*
705  *
706  */
707 void
vnode_pager_cluster_write(vnode_pager_t vnode_object,vm_object_offset_t offset,vm_size_t cnt,vm_object_offset_t * resid_offset,int * io_error,int upl_flags)708 vnode_pager_cluster_write(
709 	vnode_pager_t           vnode_object,
710 	vm_object_offset_t      offset,
711 	vm_size_t               cnt,
712 	vm_object_offset_t   *  resid_offset,
713 	int                  *  io_error,
714 	int                     upl_flags)
715 {
716 	vm_size_t       size;
717 	int             errno;
718 
719 	if (upl_flags & UPL_MSYNC) {
720 		upl_flags |= UPL_VNODE_PAGER;
721 
722 		if ((upl_flags & UPL_IOSYNC) && io_error) {
723 			upl_flags |= UPL_KEEPCACHED;
724 		}
725 
726 		while (cnt) {
727 			size = (cnt < MAX_UPL_TRANSFER_BYTES) ? cnt : MAX_UPL_TRANSFER_BYTES; /* effective max */
728 
729 			assert((upl_size_t) size == size);
730 			vnode_pageout(vnode_object->vnode_handle,
731 			    NULL, (upl_offset_t)0, offset, (upl_size_t)size, upl_flags, &errno);
732 
733 			if ((upl_flags & UPL_KEEPCACHED)) {
734 				if ((*io_error = errno)) {
735 					break;
736 				}
737 			}
738 			cnt    -= size;
739 			offset += size;
740 		}
741 		if (resid_offset) {
742 			*resid_offset = offset;
743 		}
744 	} else {
745 		vm_object_offset_t      vnode_size;
746 		vm_object_offset_t      base_offset;
747 
748 		/*
749 		 * this is the pageout path
750 		 */
751 		vnode_size = vnode_pager_get_filesize(vnode_object->vnode_handle);
752 
753 		if (vnode_size > (offset + PAGE_SIZE)) {
754 			/*
755 			 * preset the maximum size of the cluster
756 			 * and put us on a nice cluster boundary...
757 			 * and then clip the size to insure we
758 			 * don't request past the end of the underlying file
759 			 */
760 			size = MAX_UPL_TRANSFER_BYTES;
761 			base_offset = offset & ~((signed)(size - 1));
762 
763 			if ((base_offset + size) > vnode_size) {
764 				size = round_page(((vm_size_t)(vnode_size - base_offset)));
765 			}
766 		} else {
767 			/*
768 			 * we've been requested to page out a page beyond the current
769 			 * end of the 'file'... don't try to cluster in this case...
770 			 * we still need to send this page through because it might
771 			 * be marked precious and the underlying filesystem may need
772 			 * to do something with it (besides page it out)...
773 			 */
774 			base_offset = offset;
775 			size = PAGE_SIZE;
776 		}
777 		assert((upl_size_t) size == size);
778 		vnode_pageout(vnode_object->vnode_handle,
779 		    NULL, (upl_offset_t)(offset - base_offset), base_offset, (upl_size_t) size,
780 		    (upl_flags & UPL_IOSYNC) | UPL_VNODE_PAGER, NULL);
781 	}
782 }
783 
784 
785 /*
786  *
787  */
788 kern_return_t
vnode_pager_cluster_read(vnode_pager_t vnode_object,vm_object_offset_t base_offset,vm_object_offset_t offset,uint32_t io_streaming,vm_size_t cnt)789 vnode_pager_cluster_read(
790 	vnode_pager_t           vnode_object,
791 	vm_object_offset_t      base_offset,
792 	vm_object_offset_t      offset,
793 	uint32_t                io_streaming,
794 	vm_size_t               cnt)
795 {
796 	int             local_error = 0;
797 	int             kret;
798 	int             flags = 0;
799 
800 	assert(!(cnt & PAGE_MASK));
801 
802 	if (io_streaming) {
803 		flags |= UPL_IOSTREAMING;
804 	}
805 
806 	assert((upl_size_t) cnt == cnt);
807 	kret = vnode_pagein(vnode_object->vnode_handle,
808 	    (upl_t) NULL,
809 	    (upl_offset_t) (offset - base_offset),
810 	    base_offset,
811 	    (upl_size_t) cnt,
812 	    flags,
813 	    &local_error);
814 /*
815  *       if(kret == PAGER_ABSENT) {
816  *       Need to work out the defs here, 1 corresponds to PAGER_ABSENT
817  *       defined in bsd/vm/vm_pager.h  However, we should not be including
818  *       that file here it is a layering violation.
819  */
820 	if (kret == 1) {
821 		int     uplflags;
822 		upl_t   upl = NULL;
823 		unsigned int    count = 0;
824 		kern_return_t   kr;
825 
826 		uplflags = (UPL_NO_SYNC |
827 		    UPL_CLEAN_IN_PLACE |
828 		    UPL_SET_INTERNAL);
829 		count = 0;
830 		assert((upl_size_t) cnt == cnt);
831 		kr = memory_object_upl_request(vnode_object->vn_pgr_hdr.mo_control,
832 		    base_offset, (upl_size_t) cnt,
833 		    &upl, NULL, &count, uplflags, VM_KERN_MEMORY_NONE);
834 		if (kr == KERN_SUCCESS) {
835 			upl_abort(upl, 0);
836 			upl_deallocate(upl);
837 		} else {
838 			/*
839 			 * We couldn't gather the page list, probably
840 			 * because the memory object doesn't have a link
841 			 * to a VM object anymore (forced unmount, for
842 			 * example).  Just return an error to the vm_fault()
843 			 * path and let it handle it.
844 			 */
845 		}
846 
847 		ktriage_record(thread_tid(current_thread()), KDBG_TRIAGE_EVENTID(KDBG_TRIAGE_SUBSYS_VM, KDBG_TRIAGE_RESERVED, KDBG_TRIAGE_VM_VNODEPAGER_CLREAD_NO_UPL), 0 /* arg */);
848 		return KERN_FAILURE;
849 	}
850 
851 	return KERN_SUCCESS;
852 }
853 
854 /*
855  *
856  */
857 vnode_pager_t
vnode_object_create(struct vnode * vp)858 vnode_object_create(
859 	struct vnode *vp)
860 {
861 	vnode_pager_t  vnode_object;
862 
863 	vnode_object = zalloc_flags(vnode_pager_zone, Z_WAITOK | Z_NOFAIL);
864 
865 	/*
866 	 * The vm_map call takes both named entry ports and raw memory
867 	 * objects in the same parameter.  We need to make sure that
868 	 * vm_map does not see this object as a named entry port.  So,
869 	 * we reserve the first word in the object for a fake ip_kotype
870 	 * setting - that will tell vm_map to use it as a memory object.
871 	 */
872 	vnode_object->vn_pgr_hdr.mo_ikot = IKOT_MEMORY_OBJECT;
873 	vnode_object->vn_pgr_hdr.mo_pager_ops = &vnode_pager_ops;
874 	vnode_object->vn_pgr_hdr.mo_control = MEMORY_OBJECT_CONTROL_NULL;
875 
876 	os_ref_init_raw(&vnode_object->vn_pgr_hdr_ref, NULL);
877 	vnode_object->vnode_handle = vp;
878 
879 	return vnode_object;
880 }
881 
882 /*
883  *
884  */
885 vnode_pager_t
vnode_pager_lookup(memory_object_t name)886 vnode_pager_lookup(
887 	memory_object_t  name)
888 {
889 	vnode_pager_t   vnode_object;
890 
891 	vnode_object = (vnode_pager_t)name;
892 	assert(vnode_object->vn_pgr_hdr.mo_pager_ops == &vnode_pager_ops);
893 	return vnode_object;
894 }
895 
896 
897 struct vnode *
vnode_pager_lookup_vnode(memory_object_t name)898 vnode_pager_lookup_vnode(
899 	memory_object_t  name)
900 {
901 	vnode_pager_t   vnode_object;
902 	vnode_object = (vnode_pager_t)name;
903 	if (vnode_object->vn_pgr_hdr.mo_pager_ops == &vnode_pager_ops) {
904 		return vnode_object->vnode_handle;
905 	} else {
906 		return NULL;
907 	}
908 }
909 
910 /*********************** proc_info implementation *************/
911 
912 #include <sys/bsdtask_info.h>
913 
914 static int fill_vnodeinfoforaddr( vm_map_entry_t entry, uintptr_t * vnodeaddr, uint32_t * vid);
915 
916 int
fill_procregioninfo(task_t task,uint64_t arg,struct proc_regioninfo_internal * pinfo,uintptr_t * vnodeaddr,uint32_t * vid)917 fill_procregioninfo(task_t task, uint64_t arg, struct proc_regioninfo_internal *pinfo, uintptr_t *vnodeaddr, uint32_t  *vid)
918 {
919 	vm_map_t map;
920 	vm_map_offset_t address = (vm_map_offset_t)arg;
921 	vm_map_entry_t          tmp_entry;
922 	vm_map_entry_t          entry;
923 	vm_map_offset_t         start;
924 	vm_region_extended_info_data_t extended;
925 	vm_region_top_info_data_t top;
926 	boolean_t do_region_footprint;
927 	int       effective_page_shift, effective_page_size;
928 
929 	task_lock(task);
930 	map = task->map;
931 	if (map == VM_MAP_NULL) {
932 		task_unlock(task);
933 		return 0;
934 	}
935 
936 	effective_page_shift = vm_self_region_page_shift(map);
937 	effective_page_size = (1 << effective_page_shift);
938 
939 	vm_map_reference(map);
940 	task_unlock(task);
941 
942 	do_region_footprint = task_self_region_footprint();
943 
944 	vm_map_lock_read(map);
945 
946 	start = address;
947 
948 	if (!vm_map_lookup_entry_allow_pgz(map, start, &tmp_entry)) {
949 		if ((entry = tmp_entry->vme_next) == vm_map_to_entry(map)) {
950 			if (do_region_footprint &&
951 			    address == tmp_entry->vme_end) {
952 				ledger_amount_t ledger_resident;
953 				ledger_amount_t ledger_compressed;
954 
955 				/*
956 				 * This request is right after the last valid
957 				 * memory region;  instead of reporting the
958 				 * end of the address space, report a fake
959 				 * memory region to account for non-volatile
960 				 * purgeable and/or ledger-tagged memory
961 				 * owned by this task.
962 				 */
963 				task_ledgers_footprint(task->ledger,
964 				    &ledger_resident,
965 				    &ledger_compressed);
966 				if (ledger_resident + ledger_compressed == 0) {
967 					/* nothing to report */
968 					vm_map_unlock_read(map);
969 					vm_map_deallocate(map);
970 					return 0;
971 				}
972 
973 				/* provide fake region for purgeable */
974 				pinfo->pri_offset = address;
975 				pinfo->pri_protection = VM_PROT_DEFAULT;
976 				pinfo->pri_max_protection = VM_PROT_DEFAULT;
977 				pinfo->pri_inheritance = VM_INHERIT_NONE;
978 				pinfo->pri_behavior = VM_BEHAVIOR_DEFAULT;
979 				pinfo->pri_user_wired_count = 0;
980 				pinfo->pri_user_tag = -1;
981 				pinfo->pri_pages_resident =
982 				    (uint32_t) (ledger_resident / effective_page_size);
983 				pinfo->pri_pages_shared_now_private = 0;
984 				pinfo->pri_pages_swapped_out =
985 				    (uint32_t) (ledger_compressed / effective_page_size);
986 				pinfo->pri_pages_dirtied =
987 				    (uint32_t) (ledger_resident / effective_page_size);
988 				pinfo->pri_ref_count = 1;
989 				pinfo->pri_shadow_depth = 0;
990 				pinfo->pri_share_mode = SM_PRIVATE;
991 				pinfo->pri_private_pages_resident =
992 				    (uint32_t) (ledger_resident / effective_page_size);
993 				pinfo->pri_shared_pages_resident = 0;
994 				pinfo->pri_obj_id = VM_OBJECT_ID_FAKE(map, task_ledgers.purgeable_nonvolatile);
995 				pinfo->pri_address = address;
996 				pinfo->pri_size =
997 				    (uint64_t) (ledger_resident + ledger_compressed);
998 				pinfo->pri_depth = 0;
999 
1000 				vm_map_unlock_read(map);
1001 				vm_map_deallocate(map);
1002 				return 1;
1003 			}
1004 			vm_map_unlock_read(map);
1005 			vm_map_deallocate(map);
1006 			return 0;
1007 		}
1008 	} else {
1009 		entry = tmp_entry;
1010 	}
1011 
1012 	start = entry->vme_start;
1013 
1014 	pinfo->pri_offset = VME_OFFSET(entry);
1015 	pinfo->pri_protection = entry->protection;
1016 	pinfo->pri_max_protection = entry->max_protection;
1017 	pinfo->pri_inheritance = entry->inheritance;
1018 	pinfo->pri_behavior = entry->behavior;
1019 	pinfo->pri_user_wired_count = entry->user_wired_count;
1020 	pinfo->pri_user_tag = VME_ALIAS(entry);
1021 
1022 	if (entry->is_sub_map) {
1023 		pinfo->pri_flags |= PROC_REGION_SUBMAP;
1024 	} else {
1025 		if (entry->is_shared) {
1026 			pinfo->pri_flags |= PROC_REGION_SHARED;
1027 		}
1028 	}
1029 
1030 
1031 	extended.protection = entry->protection;
1032 	extended.user_tag = VME_ALIAS(entry);
1033 	extended.pages_resident = 0;
1034 	extended.pages_swapped_out = 0;
1035 	extended.pages_shared_now_private = 0;
1036 	extended.pages_dirtied = 0;
1037 	extended.external_pager = 0;
1038 	extended.shadow_depth = 0;
1039 
1040 	vm_map_region_walk(map, start, entry, VME_OFFSET(entry), entry->vme_end - start, &extended, TRUE, VM_REGION_EXTENDED_INFO_COUNT);
1041 
1042 	if (extended.external_pager && extended.ref_count == 2 && extended.share_mode == SM_SHARED) {
1043 		extended.share_mode = SM_PRIVATE;
1044 	}
1045 
1046 	top.private_pages_resident = 0;
1047 	top.shared_pages_resident = 0;
1048 	vm_map_region_top_walk(entry, &top);
1049 
1050 
1051 	pinfo->pri_pages_resident = extended.pages_resident;
1052 	pinfo->pri_pages_shared_now_private = extended.pages_shared_now_private;
1053 	pinfo->pri_pages_swapped_out = extended.pages_swapped_out;
1054 	pinfo->pri_pages_dirtied = extended.pages_dirtied;
1055 	pinfo->pri_ref_count = extended.ref_count;
1056 	pinfo->pri_shadow_depth = extended.shadow_depth;
1057 	pinfo->pri_share_mode = extended.share_mode;
1058 
1059 	pinfo->pri_private_pages_resident = top.private_pages_resident;
1060 	pinfo->pri_shared_pages_resident = top.shared_pages_resident;
1061 	pinfo->pri_obj_id = top.obj_id;
1062 
1063 	pinfo->pri_address = (uint64_t)start;
1064 	pinfo->pri_size = (uint64_t)(entry->vme_end - start);
1065 	pinfo->pri_depth = 0;
1066 
1067 	if ((vnodeaddr != 0) && (entry->is_sub_map == 0)) {
1068 		*vnodeaddr = (uintptr_t)0;
1069 
1070 		if (fill_vnodeinfoforaddr(entry, vnodeaddr, vid) == 0) {
1071 			vm_map_unlock_read(map);
1072 			vm_map_deallocate(map);
1073 			return 1;
1074 		}
1075 	}
1076 
1077 	vm_map_unlock_read(map);
1078 	vm_map_deallocate(map);
1079 	return 1;
1080 }
1081 
1082 int
fill_procregioninfo_onlymappedvnodes(task_t task,uint64_t arg,struct proc_regioninfo_internal * pinfo,uintptr_t * vnodeaddr,uint32_t * vid)1083 fill_procregioninfo_onlymappedvnodes(task_t task, uint64_t arg, struct proc_regioninfo_internal *pinfo, uintptr_t *vnodeaddr, uint32_t  *vid)
1084 {
1085 	vm_map_t map;
1086 	vm_map_offset_t address = (vm_map_offset_t)arg;
1087 	vm_map_entry_t          tmp_entry;
1088 	vm_map_entry_t          entry;
1089 
1090 	task_lock(task);
1091 	map = task->map;
1092 	if (map == VM_MAP_NULL) {
1093 		task_unlock(task);
1094 		return 0;
1095 	}
1096 	vm_map_reference(map);
1097 	task_unlock(task);
1098 
1099 	vm_map_lock_read(map);
1100 
1101 	if (!vm_map_lookup_entry_allow_pgz(map, address, &tmp_entry)) {
1102 		if ((entry = tmp_entry->vme_next) == vm_map_to_entry(map)) {
1103 			vm_map_unlock_read(map);
1104 			vm_map_deallocate(map);
1105 			return 0;
1106 		}
1107 	} else {
1108 		entry = tmp_entry;
1109 	}
1110 
1111 	while (entry != vm_map_to_entry(map)) {
1112 		*vnodeaddr = 0;
1113 		*vid = 0;
1114 
1115 		if (entry->is_sub_map == 0) {
1116 			if (fill_vnodeinfoforaddr(entry, vnodeaddr, vid)) {
1117 				pinfo->pri_offset = VME_OFFSET(entry);
1118 				pinfo->pri_protection = entry->protection;
1119 				pinfo->pri_max_protection = entry->max_protection;
1120 				pinfo->pri_inheritance = entry->inheritance;
1121 				pinfo->pri_behavior = entry->behavior;
1122 				pinfo->pri_user_wired_count = entry->user_wired_count;
1123 				pinfo->pri_user_tag = VME_ALIAS(entry);
1124 
1125 				if (entry->is_shared) {
1126 					pinfo->pri_flags |= PROC_REGION_SHARED;
1127 				}
1128 
1129 				pinfo->pri_pages_resident = 0;
1130 				pinfo->pri_pages_shared_now_private = 0;
1131 				pinfo->pri_pages_swapped_out = 0;
1132 				pinfo->pri_pages_dirtied = 0;
1133 				pinfo->pri_ref_count = 0;
1134 				pinfo->pri_shadow_depth = 0;
1135 				pinfo->pri_share_mode = 0;
1136 
1137 				pinfo->pri_private_pages_resident = 0;
1138 				pinfo->pri_shared_pages_resident = 0;
1139 				pinfo->pri_obj_id = 0;
1140 
1141 				pinfo->pri_address = (uint64_t)entry->vme_start;
1142 				pinfo->pri_size = (uint64_t)(entry->vme_end - entry->vme_start);
1143 				pinfo->pri_depth = 0;
1144 
1145 				vm_map_unlock_read(map);
1146 				vm_map_deallocate(map);
1147 				return 1;
1148 			}
1149 		}
1150 
1151 		/* Keep searching for a vnode-backed mapping */
1152 		entry = entry->vme_next;
1153 	}
1154 
1155 	vm_map_unlock_read(map);
1156 	vm_map_deallocate(map);
1157 	return 0;
1158 }
1159 
1160 int
find_region_details(task_t task,vm_map_offset_t offset,uintptr_t * vnodeaddr,uint32_t * vid,uint64_t * start,uint64_t * len)1161 find_region_details(task_t task, vm_map_offset_t offset,
1162     uintptr_t *vnodeaddr, uint32_t *vid,
1163     uint64_t *start, uint64_t *len)
1164 {
1165 	vm_map_t        map;
1166 	vm_map_entry_t  tmp_entry, entry;
1167 	int             rc = 0;
1168 
1169 	task_lock(task);
1170 	map = task->map;
1171 	if (map == VM_MAP_NULL) {
1172 		task_unlock(task);
1173 		return 0;
1174 	}
1175 	vm_map_reference(map);
1176 	task_unlock(task);
1177 
1178 	vm_map_lock_read(map);
1179 	if (!vm_map_lookup_entry_allow_pgz(map, offset, &tmp_entry)) {
1180 		if ((entry = tmp_entry->vme_next) == vm_map_to_entry(map)) {
1181 			rc = 0;
1182 			goto ret;
1183 		}
1184 	} else {
1185 		entry = tmp_entry;
1186 	}
1187 
1188 	while (entry != vm_map_to_entry(map)) {
1189 		*vnodeaddr = 0;
1190 		*vid = 0;
1191 		*start = 0;
1192 		*len = 0;
1193 
1194 		if (entry->is_sub_map == 0) {
1195 			if (fill_vnodeinfoforaddr(entry, vnodeaddr, vid)) {
1196 				*start = entry->vme_start;
1197 				*len = entry->vme_end - entry->vme_start;
1198 				rc = 1;
1199 				goto ret;
1200 			}
1201 		}
1202 
1203 		entry = entry->vme_next;
1204 	}
1205 
1206 ret:
1207 	vm_map_unlock_read(map);
1208 	vm_map_deallocate(map);
1209 	return rc;
1210 }
1211 
1212 static int
fill_vnodeinfoforaddr(vm_map_entry_t entry,uintptr_t * vnodeaddr,uint32_t * vid)1213 fill_vnodeinfoforaddr(
1214 	vm_map_entry_t                  entry,
1215 	uintptr_t * vnodeaddr,
1216 	uint32_t * vid)
1217 {
1218 	vm_object_t     top_object, object;
1219 	memory_object_t memory_object;
1220 	memory_object_pager_ops_t pager_ops;
1221 	kern_return_t   kr;
1222 	int             shadow_depth;
1223 
1224 
1225 	if (entry->is_sub_map) {
1226 		return 0;
1227 	} else {
1228 		/*
1229 		 * The last object in the shadow chain has the
1230 		 * relevant pager information.
1231 		 */
1232 		top_object = VME_OBJECT(entry);
1233 		if (top_object == VM_OBJECT_NULL) {
1234 			object = VM_OBJECT_NULL;
1235 			shadow_depth = 0;
1236 		} else {
1237 			vm_object_lock(top_object);
1238 			for (object = top_object, shadow_depth = 0;
1239 			    object->shadow != VM_OBJECT_NULL;
1240 			    object = object->shadow, shadow_depth++) {
1241 				vm_object_lock(object->shadow);
1242 				vm_object_unlock(object);
1243 			}
1244 		}
1245 	}
1246 
1247 	if (object == VM_OBJECT_NULL) {
1248 		return 0;
1249 	} else if (object->internal) {
1250 		vm_object_unlock(object);
1251 		return 0;
1252 	} else if (!object->pager_ready ||
1253 	    object->terminating ||
1254 	    !object->alive ||
1255 	    object->pager == NULL) {
1256 		vm_object_unlock(object);
1257 		return 0;
1258 	} else {
1259 		memory_object = object->pager;
1260 		pager_ops = memory_object->mo_pager_ops;
1261 		if (pager_ops == &vnode_pager_ops) {
1262 			kr = vnode_pager_get_object_vnode(
1263 				memory_object,
1264 				vnodeaddr, vid);
1265 			if (kr != KERN_SUCCESS) {
1266 				vm_object_unlock(object);
1267 				return 0;
1268 			}
1269 		} else {
1270 			vm_object_unlock(object);
1271 			return 0;
1272 		}
1273 	}
1274 	vm_object_unlock(object);
1275 	return 1;
1276 }
1277 
1278 kern_return_t
vnode_pager_get_object_vnode(memory_object_t mem_obj,uintptr_t * vnodeaddr,uint32_t * vid)1279 vnode_pager_get_object_vnode(
1280 	memory_object_t         mem_obj,
1281 	uintptr_t * vnodeaddr,
1282 	uint32_t * vid)
1283 {
1284 	vnode_pager_t   vnode_object;
1285 
1286 	vnode_object = vnode_pager_lookup(mem_obj);
1287 	if (vnode_object->vnode_handle) {
1288 		*vnodeaddr = (uintptr_t)vnode_object->vnode_handle;
1289 		*vid = (uint32_t)vnode_vid((void *)vnode_object->vnode_handle);
1290 
1291 		return KERN_SUCCESS;
1292 	}
1293 
1294 	return KERN_FAILURE;
1295 }
1296 
1297 #if CONFIG_IOSCHED
1298 kern_return_t
vnode_pager_get_object_devvp(memory_object_t mem_obj,uintptr_t * devvp)1299 vnode_pager_get_object_devvp(
1300 	memory_object_t         mem_obj,
1301 	uintptr_t               *devvp)
1302 {
1303 	struct vnode    *vp;
1304 	uint32_t        vid;
1305 
1306 	if (vnode_pager_get_object_vnode(mem_obj, (uintptr_t *)&vp, (uint32_t *)&vid) != KERN_SUCCESS) {
1307 		return KERN_FAILURE;
1308 	}
1309 	*devvp = (uintptr_t)vnode_mountdevvp(vp);
1310 	if (*devvp) {
1311 		return KERN_SUCCESS;
1312 	}
1313 	return KERN_FAILURE;
1314 }
1315 #endif
1316 
1317 /*
1318  * Find the underlying vnode object for the given vm_map_entry.  If found, return with the
1319  * object locked, otherwise return NULL with nothing locked.
1320  */
1321 
1322 vm_object_t
find_vnode_object(vm_map_entry_t entry)1323 find_vnode_object(
1324 	vm_map_entry_t  entry
1325 	)
1326 {
1327 	vm_object_t                     top_object, object;
1328 	memory_object_t                 memory_object;
1329 	memory_object_pager_ops_t       pager_ops;
1330 
1331 	if (!entry->is_sub_map) {
1332 		/*
1333 		 * The last object in the shadow chain has the
1334 		 * relevant pager information.
1335 		 */
1336 
1337 		top_object = VME_OBJECT(entry);
1338 
1339 		if (top_object) {
1340 			vm_object_lock(top_object);
1341 
1342 			for (object = top_object; object->shadow != VM_OBJECT_NULL; object = object->shadow) {
1343 				vm_object_lock(object->shadow);
1344 				vm_object_unlock(object);
1345 			}
1346 
1347 			if (object &&
1348 			    !object->internal &&
1349 			    object->pager_ready &&
1350 			    !object->terminating &&
1351 			    object->alive &&
1352 			    object->pager != NULL) {
1353 				memory_object = object->pager;
1354 				pager_ops = memory_object->mo_pager_ops;
1355 
1356 				/*
1357 				 * If this object points to the vnode_pager_ops, then we found what we're
1358 				 * looking for.  Otherwise, this vm_map_entry doesn't have an underlying
1359 				 * vnode and so we fall through to the bottom and return NULL.
1360 				 */
1361 
1362 				if (pager_ops == &vnode_pager_ops) {
1363 					return object;          /* we return with the object locked */
1364 				}
1365 			}
1366 
1367 			vm_object_unlock(object);
1368 		}
1369 	}
1370 
1371 	return VM_OBJECT_NULL;
1372 }
1373