xref: /xnu-12377.1.9/osfmk/vm/bsd_vm.c (revision f6217f891ac0bb64f3d375211650a4c1ff8ca1ea)
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 <vm/vm_map_internal.h>
50 #include <vm/vm_pageout_internal.h>
51 #include <vm/memory_object_internal.h>
52 #include <vm/vm_pageout.h>
53 #include <vm/vm_protos_internal.h>
54 #include <vm/vm_purgeable_internal.h>
55 #include <vm/vm_ubc.h>
56 #include <vm/vm_page_internal.h>
57 #include <vm/vm_object_internal.h>
58 
59 #include <sys/kdebug_triage.h>
60 
61 /* BSD VM COMPONENT INTERFACES */
62 int
get_map_nentries(vm_map_t map)63 get_map_nentries(
64 	vm_map_t map)
65 {
66 	return map->hdr.nentries;
67 }
68 
69 /*
70  * BSD VNODE PAGER
71  */
72 
73 const struct memory_object_pager_ops vnode_pager_ops = {
74 	.memory_object_reference = vnode_pager_reference,
75 	.memory_object_deallocate = vnode_pager_deallocate,
76 	.memory_object_init = vnode_pager_init,
77 	.memory_object_terminate = vnode_pager_terminate,
78 	.memory_object_data_request = vnode_pager_data_request,
79 	.memory_object_data_return = vnode_pager_data_return,
80 	.memory_object_data_initialize = vnode_pager_data_initialize,
81 	.memory_object_map = vnode_pager_map,
82 	.memory_object_last_unmap = vnode_pager_last_unmap,
83 	.memory_object_backing_object = NULL,
84 	.memory_object_pager_name = "vnode pager"
85 };
86 
87 typedef struct vnode_pager {
88 	/* mandatory generic header */
89 	struct memory_object vn_pgr_hdr;
90 
91 	/*  pager-specific */
92 #if MEMORY_OBJECT_HAS_REFCOUNT
93 #define vn_pgr_hdr_ref      vn_pgr_hdr.mo_ref
94 #else
95 	os_ref_atomic_t         vn_pgr_hdr_ref;
96 #endif
97 	struct vnode            *vnode_handle;  /* vnode handle              */
98 } *vnode_pager_t;
99 
100 
101 kern_return_t
102 vnode_pager_cluster_read(               /* forward */
103 	vnode_pager_t,
104 	vm_object_offset_t,
105 	vm_object_offset_t,
106 	uint32_t,
107 	vm_size_t);
108 
109 void
110 vnode_pager_cluster_write(              /* forward */
111 	vnode_pager_t,
112 	vm_object_offset_t,
113 	vm_size_t,
114 	vm_object_offset_t *,
115 	int *,
116 	int);
117 
118 
119 vnode_pager_t
120 vnode_object_create(                    /* forward */
121 	struct vnode *);
122 
123 vnode_pager_t
124 vnode_pager_lookup(                     /* forward */
125 	memory_object_t);
126 
127 struct vnode *
128 vnode_pager_lookup_vnode(               /* forward */
129 	memory_object_t);
130 
131 ZONE_DEFINE_TYPE(vnode_pager_zone, "vnode pager structures",
132     struct vnode_pager, ZC_NOENCRYPT);
133 
134 #define VNODE_PAGER_NULL        ((vnode_pager_t) 0)
135 
136 /* TODO: Should be set dynamically by vnode_pager_init() */
137 #define CLUSTER_SHIFT   1
138 
139 
140 #if DEBUG
141 int pagerdebug = 0;
142 
143 #define PAGER_ALL               0xffffffff
144 #define PAGER_INIT              0x00000001
145 #define PAGER_PAGEIN    0x00000002
146 
147 #define PAGER_DEBUG(LEVEL, A) {if ((pagerdebug & LEVEL)==LEVEL){printf A;}}
148 #else
149 #define PAGER_DEBUG(LEVEL, A)
150 #endif
151 
152 extern int proc_resetpcontrol(int);
153 
154 
155 extern int      uiomove64(addr64_t, int, void *);
156 #define MAX_RUN 32
157 
158 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)159 memory_object_control_uiomove(
160 	memory_object_control_t control,
161 	memory_object_offset_t  offset,
162 	void            *       uio,
163 	int                     start_offset,
164 	int                     io_requested,
165 	int                     mark_dirty,
166 	int                     take_reference)
167 {
168 	vm_object_t             object;
169 	vm_page_t               dst_page;
170 	int                     xsize;
171 	int                     retval = 0;
172 	int                     cur_run;
173 	int                     cur_needed;
174 	int                     i;
175 	int                     orig_offset;
176 	vm_page_t               page_run[MAX_RUN];
177 	int                     dirty_count;    /* keeps track of number of pages dirtied as part of this uiomove */
178 
179 	object = memory_object_control_to_vm_object(control);
180 	if (object == VM_OBJECT_NULL) {
181 		return 0;
182 	}
183 	assert(!object->internal);
184 
185 	vm_object_lock(object);
186 
187 	if (mark_dirty && object->vo_copy != VM_OBJECT_NULL) {
188 		/*
189 		 * We can't modify the pages without honoring
190 		 * copy-on-write obligations first, so fall off
191 		 * this optimized path and fall back to the regular
192 		 * path.
193 		 */
194 		vm_object_unlock(object);
195 		return 0;
196 	}
197 	orig_offset = start_offset;
198 
199 	dirty_count = 0;
200 	while (io_requested && retval == 0) {
201 		cur_needed = (start_offset + io_requested + (PAGE_SIZE - 1)) / PAGE_SIZE;
202 
203 		if (cur_needed > MAX_RUN) {
204 			cur_needed = MAX_RUN;
205 		}
206 
207 		for (cur_run = 0; cur_run < cur_needed;) {
208 			if (mark_dirty && object->vo_copy != VM_OBJECT_NULL) {
209 				/*
210 				 * We checked that this file-backed object did not have
211 				 * a copy object when we entered this routine but it now has
212 				 * one, so we can't stay on this optimized path.
213 				 * We can finish processing the pages we have already grabbed
214 				 * because they were made "busy" before the copy object was
215 				 * created so they can't have been seen through that copy
216 				 * object yet.
217 				 */
218 				break;
219 			}
220 
221 			if ((dst_page = vm_page_lookup(object, offset)) == VM_PAGE_NULL) {
222 				break;
223 			}
224 
225 			if (__improbable(dst_page->vmp_error)) {
226 				retval = EIO;
227 				break;
228 			}
229 			if (dst_page->vmp_busy || dst_page->vmp_cleaning) {
230 				/*
231 				 * someone else is playing with the page... if we've
232 				 * already collected pages into this run, go ahead
233 				 * and process now, we can't block on this
234 				 * page while holding other pages in the BUSY state
235 				 * otherwise we will wait
236 				 */
237 				if (cur_run) {
238 					break;
239 				}
240 				vm_page_sleep(object, dst_page, THREAD_UNINT, LCK_SLEEP_EXCLUSIVE);
241 				continue;
242 			}
243 			if (dst_page->vmp_laundry) {
244 				vm_pageout_steal_laundry(dst_page, FALSE);
245 			}
246 			if (__improbable(dst_page->vmp_absent)) {
247 				printf("absent page %p (obj %p offset 0x%llx) -> EIO",
248 				    dst_page, object, offset);
249 				retval = EIO;
250 				break;
251 			}
252 
253 			if (mark_dirty) {
254 #if CONFIG_SPTM
255 				if (__improbable(PMAP_PAGE_IS_USER_EXECUTABLE(dst_page))) {
256 					/*
257 					 * This is analogous to the PMAP_OPTIONS_RETYPE disconnect we perform
258 					 * in vm_object_upl_request() when setting up a UPL to overwrite the
259 					 * destination pages, which is the UPL-based analogue of this path.
260 					 * See the comment there for the gory details, but it essentially boils
261 					 * down to the same situation of being asked to overwrite page contents
262 					 * that were already marked executable from some prior use of the vnode
263 					 * associated with this VM object.
264 					 */
265 					pmap_disconnect_options(VM_PAGE_GET_PHYS_PAGE(dst_page), PMAP_OPTIONS_RETYPE, NULL);
266 				}
267 #endif /* CONFIG_SPTM */
268 				if (dst_page->vmp_dirty == FALSE) {
269 					dirty_count++;
270 				}
271 				SET_PAGE_DIRTY(dst_page, FALSE);
272 				if (dst_page->vmp_cs_validated &&
273 				    !dst_page->vmp_cs_tainted) {
274 					/*
275 					 * CODE SIGNING:
276 					 * We're modifying a code-signed
277 					 * page: force revalidate
278 					 */
279 					dst_page->vmp_cs_validated = VMP_CS_ALL_FALSE;
280 
281 					VM_PAGEOUT_DEBUG(vm_cs_validated_resets, 1);
282 
283 					pmap_disconnect(VM_PAGE_GET_PHYS_PAGE(dst_page));
284 				}
285 			}
286 			dst_page->vmp_busy = TRUE;
287 
288 			page_run[cur_run++] = dst_page;
289 
290 			offset += PAGE_SIZE_64;
291 		}
292 		if (cur_run == 0) {
293 			/*
294 			 * we hit a 'hole' in the cache or
295 			 * a page we don't want to try to handle,
296 			 * so bail at this point
297 			 * we'll unlock the object below
298 			 */
299 			break;
300 		}
301 		vm_object_unlock(object);
302 
303 		for (i = 0; i < cur_run; i++) {
304 			dst_page = page_run[i];
305 
306 			if ((xsize = PAGE_SIZE - start_offset) > io_requested) {
307 				xsize = io_requested;
308 			}
309 
310 			/* Such phyiscal pages should never be restricted pages */
311 			if (vm_page_is_restricted(dst_page)) {
312 				panic("%s: cannot uiomove64 into restricted page", __func__);
313 			}
314 
315 			if ((retval = uiomove64((addr64_t)(((addr64_t)(VM_PAGE_GET_PHYS_PAGE(dst_page)) << PAGE_SHIFT) + start_offset), xsize, uio))) {
316 				break;
317 			}
318 
319 			io_requested -= xsize;
320 			start_offset = 0;
321 		}
322 		vm_object_lock(object);
323 
324 		/*
325 		 * if we have more than 1 page to work on
326 		 * in the current run, or the original request
327 		 * started at offset 0 of the page, or we're
328 		 * processing multiple batches, we will move
329 		 * the pages to the tail of the inactive queue
330 		 * to implement an LRU for read/write accesses
331 		 *
332 		 * the check for orig_offset == 0 is there to
333 		 * mitigate the cost of small (< page_size) requests
334 		 * to the same page (this way we only move it once)
335 		 */
336 		if (take_reference && (cur_run > 1 || orig_offset == 0)) {
337 			vm_page_lockspin_queues();
338 
339 			for (i = 0; i < cur_run; i++) {
340 				vm_page_lru(page_run[i]);
341 			}
342 
343 			vm_page_unlock_queues();
344 		}
345 		for (i = 0; i < cur_run; i++) {
346 			dst_page = page_run[i];
347 
348 			/*
349 			 * someone is explicitly referencing this page...
350 			 * update clustered and speculative state
351 			 *
352 			 */
353 			if (dst_page->vmp_clustered) {
354 				VM_PAGE_CONSUME_CLUSTERED(dst_page);
355 			}
356 
357 			vm_page_wakeup_done(object, dst_page);
358 		}
359 		orig_offset = 0;
360 	}
361 	vm_object_unlock(object);
362 	return retval;
363 }
364 
365 
366 bool
memory_object_is_vnode_pager(memory_object_t mem_obj)367 memory_object_is_vnode_pager(
368 	memory_object_t mem_obj)
369 {
370 	if (mem_obj != NULL &&
371 	    mem_obj->mo_pager_ops == &vnode_pager_ops) {
372 		return true;
373 	}
374 	return false;
375 }
376 
377 /*
378  *
379  */
380 memory_object_t
vnode_pager_setup(struct vnode * vp,__unused memory_object_t pager)381 vnode_pager_setup(
382 	struct vnode    *vp,
383 	__unused memory_object_t        pager)
384 {
385 	vnode_pager_t   vnode_object;
386 
387 	vnode_object = vnode_object_create(vp);
388 	if (vnode_object == VNODE_PAGER_NULL) {
389 		panic("vnode_pager_setup: vnode_object_create() failed");
390 	}
391 	return (memory_object_t)vnode_object;
392 }
393 
394 /*
395  *
396  */
397 kern_return_t
vnode_pager_init(memory_object_t mem_obj,memory_object_control_t control,__unused memory_object_cluster_size_t pg_size)398 vnode_pager_init(memory_object_t mem_obj,
399     memory_object_control_t control,
400 #if !DEBUG
401     __unused
402 #endif
403     memory_object_cluster_size_t pg_size)
404 {
405 	vnode_pager_t   vnode_object;
406 	kern_return_t   kr;
407 	memory_object_attr_info_data_t  attributes;
408 
409 
410 	PAGER_DEBUG(PAGER_ALL, ("vnode_pager_init: %p, %p, %lx\n", mem_obj, control, (unsigned long)pg_size));
411 
412 	if (control == MEMORY_OBJECT_CONTROL_NULL) {
413 		return KERN_INVALID_ARGUMENT;
414 	}
415 
416 	vnode_object = vnode_pager_lookup(mem_obj);
417 
418 	memory_object_control_reference(control);
419 
420 	vnode_object->vn_pgr_hdr.mo_control = control;
421 
422 	attributes.copy_strategy = MEMORY_OBJECT_COPY_DELAY;
423 	/* attributes.cluster_size = (1 << (CLUSTER_SHIFT + PAGE_SHIFT));*/
424 	attributes.cluster_size = (1 << (PAGE_SHIFT));
425 	attributes.may_cache_object = TRUE;
426 	attributes.temporary = TRUE;
427 
428 	kr = memory_object_change_attributes(
429 		control,
430 		MEMORY_OBJECT_ATTRIBUTE_INFO,
431 		(memory_object_info_t) &attributes,
432 		MEMORY_OBJECT_ATTR_INFO_COUNT);
433 	if (kr != KERN_SUCCESS) {
434 		panic("vnode_pager_init: memory_object_change_attributes() failed");
435 	}
436 
437 	return KERN_SUCCESS;
438 }
439 
440 /*
441  *
442  */
443 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)444 vnode_pager_data_return(
445 	memory_object_t         mem_obj,
446 	memory_object_offset_t  offset,
447 	memory_object_cluster_size_t            data_cnt,
448 	memory_object_offset_t  *resid_offset,
449 	int                     *io_error,
450 	__unused boolean_t              dirty,
451 	__unused boolean_t              kernel_copy,
452 	int                     upl_flags)
453 {
454 	vnode_pager_t   vnode_object;
455 
456 	assertf(page_aligned(offset), "offset 0x%llx\n", offset);
457 
458 	vnode_object = vnode_pager_lookup(mem_obj);
459 
460 	vnode_pager_cluster_write(vnode_object, offset, data_cnt, resid_offset, io_error, upl_flags);
461 
462 	return KERN_SUCCESS;
463 }
464 
465 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)466 vnode_pager_data_initialize(
467 	__unused memory_object_t                mem_obj,
468 	__unused memory_object_offset_t offset,
469 	__unused memory_object_cluster_size_t           data_cnt)
470 {
471 	panic("vnode_pager_data_initialize");
472 	return KERN_FAILURE;
473 }
474 
475 void
vnode_pager_dirtied(memory_object_t mem_obj,vm_object_offset_t s_offset,vm_object_offset_t e_offset)476 vnode_pager_dirtied(
477 	memory_object_t         mem_obj,
478 	vm_object_offset_t      s_offset,
479 	vm_object_offset_t      e_offset)
480 {
481 	vnode_pager_t   vnode_object;
482 
483 	if (mem_obj && mem_obj->mo_pager_ops == &vnode_pager_ops) {
484 		vnode_object = vnode_pager_lookup(mem_obj);
485 		vnode_pager_was_dirtied(vnode_object->vnode_handle, s_offset, e_offset);
486 	}
487 }
488 
489 kern_return_t
vnode_pager_get_isinuse(memory_object_t mem_obj,uint32_t * isinuse)490 vnode_pager_get_isinuse(
491 	memory_object_t         mem_obj,
492 	uint32_t                *isinuse)
493 {
494 	vnode_pager_t   vnode_object;
495 
496 	if (mem_obj->mo_pager_ops != &vnode_pager_ops) {
497 		*isinuse = 1;
498 		return KERN_INVALID_ARGUMENT;
499 	}
500 
501 	vnode_object = vnode_pager_lookup(mem_obj);
502 
503 	*isinuse = vnode_pager_isinuse(vnode_object->vnode_handle);
504 	return KERN_SUCCESS;
505 }
506 
507 kern_return_t
vnode_pager_get_throttle_io_limit(memory_object_t mem_obj,uint32_t * limit)508 vnode_pager_get_throttle_io_limit(
509 	memory_object_t         mem_obj,
510 	uint32_t                *limit)
511 {
512 	vnode_pager_t   vnode_object;
513 
514 	if (mem_obj->mo_pager_ops != &vnode_pager_ops) {
515 		return KERN_INVALID_ARGUMENT;
516 	}
517 
518 	vnode_object = vnode_pager_lookup(mem_obj);
519 
520 	(void)vnode_pager_return_throttle_io_limit(vnode_object->vnode_handle, limit);
521 	return KERN_SUCCESS;
522 }
523 
524 kern_return_t
vnode_pager_get_isSSD(memory_object_t mem_obj,boolean_t * isSSD)525 vnode_pager_get_isSSD(
526 	memory_object_t         mem_obj,
527 	boolean_t               *isSSD)
528 {
529 	vnode_pager_t   vnode_object;
530 
531 	if (mem_obj->mo_pager_ops != &vnode_pager_ops) {
532 		return KERN_INVALID_ARGUMENT;
533 	}
534 
535 	vnode_object = vnode_pager_lookup(mem_obj);
536 
537 	*isSSD = vnode_pager_isSSD(vnode_object->vnode_handle);
538 	return KERN_SUCCESS;
539 }
540 
541 #if FBDP_DEBUG_OBJECT_NO_PAGER
542 kern_return_t
vnode_pager_get_forced_unmount(memory_object_t mem_obj,bool * forced_unmount)543 vnode_pager_get_forced_unmount(
544 	memory_object_t         mem_obj,
545 	bool                    *forced_unmount)
546 {
547 	vnode_pager_t   vnode_object;
548 
549 	if (mem_obj->mo_pager_ops != &vnode_pager_ops) {
550 		return KERN_INVALID_ARGUMENT;
551 	}
552 
553 	vnode_object = vnode_pager_lookup(mem_obj);
554 
555 	*forced_unmount = vnode_pager_forced_unmount(vnode_object->vnode_handle);
556 	return KERN_SUCCESS;
557 }
558 #endif /* FBDP_DEBUG_OBJECT_NO_PAGER */
559 
560 kern_return_t
vnode_pager_get_object_size(memory_object_t mem_obj,memory_object_offset_t * length)561 vnode_pager_get_object_size(
562 	memory_object_t         mem_obj,
563 	memory_object_offset_t  *length)
564 {
565 	vnode_pager_t   vnode_object;
566 
567 	if (mem_obj->mo_pager_ops != &vnode_pager_ops) {
568 		*length = 0;
569 		return KERN_INVALID_ARGUMENT;
570 	}
571 
572 	vnode_object = vnode_pager_lookup(mem_obj);
573 
574 	*length = vnode_pager_get_filesize(vnode_object->vnode_handle);
575 	return KERN_SUCCESS;
576 }
577 
578 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)579 vnode_pager_get_object_name(
580 	memory_object_t         mem_obj,
581 	char                    *pathname,
582 	vm_size_t               pathname_len,
583 	char                    *filename,
584 	vm_size_t               filename_len,
585 	boolean_t               *truncated_path_p)
586 {
587 	vnode_pager_t   vnode_object;
588 
589 	if (mem_obj->mo_pager_ops != &vnode_pager_ops) {
590 		return KERN_INVALID_ARGUMENT;
591 	}
592 
593 	vnode_object = vnode_pager_lookup(mem_obj);
594 
595 	return vnode_pager_get_name(vnode_object->vnode_handle,
596 	           pathname,
597 	           pathname_len,
598 	           filename,
599 	           filename_len,
600 	           truncated_path_p);
601 }
602 
603 kern_return_t
vnode_pager_get_object_mtime(memory_object_t mem_obj,struct timespec * mtime,struct timespec * cs_mtime)604 vnode_pager_get_object_mtime(
605 	memory_object_t         mem_obj,
606 	struct timespec         *mtime,
607 	struct timespec         *cs_mtime)
608 {
609 	vnode_pager_t   vnode_object;
610 
611 	if (mem_obj->mo_pager_ops != &vnode_pager_ops) {
612 		return KERN_INVALID_ARGUMENT;
613 	}
614 
615 	vnode_object = vnode_pager_lookup(mem_obj);
616 
617 	return vnode_pager_get_mtime(vnode_object->vnode_handle,
618 	           mtime,
619 	           cs_mtime);
620 }
621 
622 #if CHECK_CS_VALIDATION_BITMAP
623 kern_return_t
vnode_pager_cs_check_validation_bitmap(memory_object_t mem_obj,memory_object_offset_t offset,int optype)624 vnode_pager_cs_check_validation_bitmap(
625 	memory_object_t mem_obj,
626 	memory_object_offset_t  offset,
627 	int             optype  )
628 {
629 	vnode_pager_t   vnode_object;
630 
631 	if (mem_obj == MEMORY_OBJECT_NULL ||
632 	    mem_obj->mo_pager_ops != &vnode_pager_ops) {
633 		return KERN_INVALID_ARGUMENT;
634 	}
635 
636 	vnode_object = vnode_pager_lookup(mem_obj);
637 	return ubc_cs_check_validation_bitmap( vnode_object->vnode_handle, offset, optype );
638 }
639 #endif /* CHECK_CS_VALIDATION_BITMAP */
640 
641 /*
642  *
643  */
644 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)645 vnode_pager_data_request(
646 	memory_object_t         mem_obj,
647 	memory_object_offset_t  offset,
648 	__unused memory_object_cluster_size_t   length,
649 	__unused vm_prot_t      desired_access,
650 	memory_object_fault_info_t      fault_info)
651 {
652 	vnode_pager_t           vnode_object;
653 	memory_object_offset_t  base_offset;
654 	vm_size_t               size;
655 	uint32_t                io_streaming = 0;
656 
657 	assertf(page_aligned(offset), "offset 0x%llx\n", offset);
658 
659 	vnode_object = vnode_pager_lookup(mem_obj);
660 
661 	size = MAX_UPL_TRANSFER_BYTES;
662 	base_offset = offset;
663 
664 	if (memory_object_cluster_size(vnode_object->vn_pgr_hdr.mo_control,
665 	    &base_offset, &size, &io_streaming,
666 	    fault_info) != KERN_SUCCESS) {
667 		size = PAGE_SIZE;
668 	}
669 
670 	assert(offset >= base_offset &&
671 	    offset < base_offset + size);
672 
673 	return vnode_pager_cluster_read(vnode_object, base_offset, offset, io_streaming, size);
674 }
675 
676 /*
677  *
678  */
679 void
vnode_pager_reference(memory_object_t mem_obj)680 vnode_pager_reference(
681 	memory_object_t         mem_obj)
682 {
683 	vnode_pager_t   vnode_object;
684 
685 	vnode_object = vnode_pager_lookup(mem_obj);
686 	os_ref_retain_raw(&vnode_object->vn_pgr_hdr_ref, NULL);
687 }
688 
689 /*
690  *
691  */
692 void
vnode_pager_deallocate(memory_object_t mem_obj)693 vnode_pager_deallocate(
694 	memory_object_t         mem_obj)
695 {
696 	vnode_pager_t   vnode_object;
697 
698 	PAGER_DEBUG(PAGER_ALL, ("vnode_pager_deallocate: %p\n", mem_obj));
699 
700 	vnode_object = vnode_pager_lookup(mem_obj);
701 
702 	if (os_ref_release_raw(&vnode_object->vn_pgr_hdr_ref, NULL) == 0) {
703 		if (vnode_object->vnode_handle != NULL) {
704 			vnode_pager_vrele(vnode_object->vnode_handle);
705 		}
706 		zfree(vnode_pager_zone, vnode_object);
707 	}
708 }
709 
710 /*
711  *
712  */
713 kern_return_t
vnode_pager_terminate(__unused memory_object_t mem_obj)714 vnode_pager_terminate(
715 #if !DEBUG
716 	__unused
717 #endif
718 	memory_object_t mem_obj)
719 {
720 	PAGER_DEBUG(PAGER_ALL, ("vnode_pager_terminate: %p\n", mem_obj));
721 
722 	return KERN_SUCCESS;
723 }
724 
725 /*
726  *
727  */
728 kern_return_t
vnode_pager_map(memory_object_t mem_obj,vm_prot_t prot)729 vnode_pager_map(
730 	memory_object_t         mem_obj,
731 	vm_prot_t               prot)
732 {
733 	vnode_pager_t           vnode_object;
734 	int                     ret;
735 	kern_return_t           kr;
736 
737 	PAGER_DEBUG(PAGER_ALL, ("vnode_pager_map: %p %x\n", mem_obj, prot));
738 
739 	vnode_object = vnode_pager_lookup(mem_obj);
740 
741 	ret = ubc_map(vnode_object->vnode_handle, prot);
742 
743 	if (ret != 0) {
744 		kr = KERN_FAILURE;
745 	} else {
746 		kr = KERN_SUCCESS;
747 	}
748 
749 	return kr;
750 }
751 
752 kern_return_t
vnode_pager_last_unmap(memory_object_t mem_obj)753 vnode_pager_last_unmap(
754 	memory_object_t         mem_obj)
755 {
756 	vnode_pager_t   vnode_object;
757 
758 	PAGER_DEBUG(PAGER_ALL, ("vnode_pager_last_unmap: %p\n", mem_obj));
759 
760 	vnode_object = vnode_pager_lookup(mem_obj);
761 
762 	ubc_unmap(vnode_object->vnode_handle);
763 	return KERN_SUCCESS;
764 }
765 
766 
767 
768 /*
769  *
770  */
771 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)772 vnode_pager_cluster_write(
773 	vnode_pager_t           vnode_object,
774 	vm_object_offset_t      offset,
775 	vm_size_t               cnt,
776 	vm_object_offset_t   *  resid_offset,
777 	int                  *  io_error,
778 	int                     upl_flags)
779 {
780 	vm_size_t       size;
781 	int             errno;
782 
783 	if (upl_flags & UPL_MSYNC) {
784 		upl_flags |= UPL_VNODE_PAGER;
785 
786 		if ((upl_flags & UPL_IOSYNC) && io_error) {
787 			upl_flags |= UPL_KEEPCACHED;
788 		}
789 
790 		while (cnt) {
791 			size = (cnt < MAX_UPL_TRANSFER_BYTES) ? cnt : MAX_UPL_TRANSFER_BYTES; /* effective max */
792 
793 			assert((upl_size_t) size == size);
794 			vnode_pageout(vnode_object->vnode_handle,
795 			    NULL, (upl_offset_t)0, offset, (upl_size_t)size, upl_flags, &errno);
796 
797 			if ((upl_flags & UPL_KEEPCACHED)) {
798 				if ((*io_error = errno)) {
799 					break;
800 				}
801 			}
802 			cnt    -= size;
803 			offset += size;
804 		}
805 		if (resid_offset) {
806 			*resid_offset = offset;
807 		}
808 	} else {
809 		vm_object_offset_t      vnode_size;
810 		vm_object_offset_t      base_offset;
811 
812 		/*
813 		 * this is the pageout path
814 		 */
815 		vnode_size = vnode_pager_get_filesize(vnode_object->vnode_handle);
816 
817 		if (vnode_size > (offset + PAGE_SIZE)) {
818 			/*
819 			 * preset the maximum size of the cluster
820 			 * and put us on a nice cluster boundary...
821 			 * and then clip the size to insure we
822 			 * don't request past the end of the underlying file
823 			 */
824 			size = MAX_UPL_TRANSFER_BYTES;
825 			base_offset = offset & ~((signed)(size - 1));
826 
827 			if ((base_offset + size) > vnode_size) {
828 				size = round_page(((vm_size_t)(vnode_size - base_offset)));
829 			}
830 		} else {
831 			/*
832 			 * we've been requested to page out a page beyond the current
833 			 * end of the 'file'... don't try to cluster in this case...
834 			 * we still need to send this page through because it might
835 			 * be marked precious and the underlying filesystem may need
836 			 * to do something with it (besides page it out)...
837 			 */
838 			base_offset = offset;
839 			size = PAGE_SIZE;
840 		}
841 		assert((upl_size_t) size == size);
842 		vnode_pageout(vnode_object->vnode_handle,
843 		    NULL, (upl_offset_t)(offset - base_offset), base_offset, (upl_size_t) size,
844 		    (upl_flags & UPL_IOSYNC) | UPL_VNODE_PAGER, NULL);
845 	}
846 }
847 
848 
849 /*
850  *
851  */
852 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)853 vnode_pager_cluster_read(
854 	vnode_pager_t           vnode_object,
855 	vm_object_offset_t      base_offset,
856 	vm_object_offset_t      offset,
857 	uint32_t                io_streaming,
858 	vm_size_t               cnt)
859 {
860 	int             local_error = 0;
861 	int             kret;
862 	int             flags = 0;
863 
864 	assert(!(cnt & PAGE_MASK));
865 
866 	if (io_streaming) {
867 		flags |= UPL_IOSTREAMING;
868 	}
869 
870 	assert((upl_size_t) cnt == cnt);
871 	kret = vnode_pagein(vnode_object->vnode_handle,
872 	    (upl_t) NULL,
873 	    (upl_offset_t) (offset - base_offset),
874 	    base_offset,
875 	    (upl_size_t) cnt,
876 	    flags,
877 	    &local_error);
878 /*
879  *       if(kret == PAGER_ABSENT) {
880  *       Need to work out the defs here, 1 corresponds to PAGER_ABSENT
881  *       defined in bsd/vm/vm_pager_xnu.h  However, we should not be including
882  *       that file here it is a layering violation.
883  */
884 	if (kret == 1) {
885 		int     uplflags;
886 		upl_t   upl = NULL;
887 		unsigned int    count = 0;
888 		kern_return_t   kr;
889 
890 		uplflags = (UPL_NO_SYNC |
891 		    UPL_CLEAN_IN_PLACE |
892 		    UPL_SET_INTERNAL);
893 		count = 0;
894 		assert((upl_size_t) cnt == cnt);
895 		kr = memory_object_upl_request(vnode_object->vn_pgr_hdr.mo_control,
896 		    base_offset, (upl_size_t) cnt,
897 		    &upl, NULL, &count, uplflags, VM_KERN_MEMORY_NONE);
898 		if (kr == KERN_SUCCESS) {
899 			upl_abort(upl, 0);
900 			upl_deallocate(upl);
901 		} else {
902 			/*
903 			 * We couldn't gather the page list, probably
904 			 * because the memory object doesn't have a link
905 			 * to a VM object anymore (forced unmount, for
906 			 * example).  Just return an error to the vm_fault()
907 			 * path and let it handle it.
908 			 */
909 		}
910 
911 		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 */);
912 		return KERN_FAILURE;
913 	}
914 
915 	return KERN_SUCCESS;
916 }
917 
918 /*
919  *
920  */
921 vnode_pager_t
vnode_object_create(struct vnode * vp)922 vnode_object_create(
923 	struct vnode *vp)
924 {
925 	vnode_pager_t  vnode_object;
926 
927 	vnode_object = zalloc_flags(vnode_pager_zone, Z_WAITOK | Z_NOFAIL);
928 
929 	/*
930 	 * The vm_map call takes both named entry ports and raw memory
931 	 * objects in the same parameter.  We need to make sure that
932 	 * vm_map does not see this object as a named entry port.  So,
933 	 * we reserve the first word in the object for a fake object type
934 	 * setting - that will tell vm_map to use it as a memory object.
935 	 */
936 	vnode_object->vn_pgr_hdr.mo_ikot = IKOT_MEMORY_OBJECT;
937 	vnode_object->vn_pgr_hdr.mo_pager_ops = &vnode_pager_ops;
938 	vnode_object->vn_pgr_hdr.mo_control = MEMORY_OBJECT_CONTROL_NULL;
939 
940 	os_ref_init_raw(&vnode_object->vn_pgr_hdr_ref, NULL);
941 	vnode_object->vnode_handle = vp;
942 
943 	return vnode_object;
944 }
945 
946 /*
947  *
948  */
949 vnode_pager_t
vnode_pager_lookup(memory_object_t name)950 vnode_pager_lookup(
951 	memory_object_t  name)
952 {
953 	vnode_pager_t   vnode_object;
954 
955 	vnode_object = (vnode_pager_t)name;
956 	assert(vnode_object->vn_pgr_hdr.mo_pager_ops == &vnode_pager_ops);
957 	return vnode_object;
958 }
959 
960 
961 struct vnode *
vnode_pager_lookup_vnode(memory_object_t name)962 vnode_pager_lookup_vnode(
963 	memory_object_t  name)
964 {
965 	vnode_pager_t   vnode_object;
966 	vnode_object = (vnode_pager_t)name;
967 	if (vnode_object->vn_pgr_hdr.mo_pager_ops == &vnode_pager_ops) {
968 		return vnode_object->vnode_handle;
969 	} else {
970 		return NULL;
971 	}
972 }
973 
974 /*********************** proc_info implementation *************/
975 
976 #include <sys/bsdtask_info.h>
977 
978 static int fill_vnodeinfoforaddr( vm_map_entry_t entry, uintptr_t * vnodeaddr, uint32_t * vid, bool *is_map_shared);
979 
980 int
fill_procregioninfo(task_t task,uint64_t arg,struct proc_regioninfo_internal * pinfo,uintptr_t * vnodeaddr,uint32_t * vid)981 fill_procregioninfo(task_t task, uint64_t arg, struct proc_regioninfo_internal *pinfo, uintptr_t *vnodeaddr, uint32_t  *vid)
982 {
983 	vm_map_t map;
984 	vm_map_offset_t address = (vm_map_offset_t)arg;
985 	vm_map_entry_t          tmp_entry;
986 	vm_map_entry_t          entry;
987 	vm_map_offset_t         start;
988 	vm_region_extended_info_data_t extended;
989 	vm_region_top_info_data_t top;
990 	boolean_t do_region_footprint;
991 	int       effective_page_shift, effective_page_size;
992 
993 	vmlp_api_start(FILL_PROCREGIONINFO);
994 
995 	task_lock(task);
996 	map = task->map;
997 	if (map == VM_MAP_NULL) {
998 		task_unlock(task);
999 		vmlp_api_end(FILL_PROCREGIONINFO, 0);
1000 		return 0;
1001 	}
1002 
1003 	effective_page_shift = vm_self_region_page_shift(map);
1004 	effective_page_size = (1 << effective_page_shift);
1005 
1006 	vm_map_reference(map);
1007 	task_unlock(task);
1008 
1009 	do_region_footprint = task_self_region_footprint();
1010 
1011 	vm_map_lock_read(map);
1012 
1013 	start = address;
1014 
1015 	if (!vm_map_lookup_entry(map, start, &tmp_entry)) {
1016 		if ((entry = tmp_entry->vme_next) == vm_map_to_entry(map)) {
1017 			if (do_region_footprint &&
1018 			    address == tmp_entry->vme_end) {
1019 				ledger_amount_t ledger_resident;
1020 				ledger_amount_t ledger_compressed;
1021 
1022 				/*
1023 				 * This request is right after the last valid
1024 				 * memory region;  instead of reporting the
1025 				 * end of the address space, report a fake
1026 				 * memory region to account for non-volatile
1027 				 * purgeable and/or ledger-tagged memory
1028 				 * owned by this task.
1029 				 */
1030 				task_ledgers_footprint(task->ledger,
1031 				    &ledger_resident,
1032 				    &ledger_compressed);
1033 				if (ledger_resident + ledger_compressed == 0) {
1034 					/* nothing to report */
1035 					vm_map_unlock_read(map);
1036 					vm_map_deallocate(map);
1037 					vmlp_api_end(FILL_PROCREGIONINFO, 0);
1038 					return 0;
1039 				}
1040 
1041 				/* provide fake region for purgeable */
1042 				pinfo->pri_offset = address;
1043 				pinfo->pri_protection = VM_PROT_DEFAULT;
1044 				pinfo->pri_max_protection = VM_PROT_DEFAULT;
1045 				pinfo->pri_inheritance = VM_INHERIT_NONE;
1046 				pinfo->pri_behavior = VM_BEHAVIOR_DEFAULT;
1047 				pinfo->pri_user_wired_count = 0;
1048 				pinfo->pri_user_tag = -1;
1049 				pinfo->pri_pages_resident =
1050 				    (uint32_t) (ledger_resident / effective_page_size);
1051 				pinfo->pri_pages_shared_now_private = 0;
1052 				pinfo->pri_pages_swapped_out =
1053 				    (uint32_t) (ledger_compressed / effective_page_size);
1054 				pinfo->pri_pages_dirtied =
1055 				    (uint32_t) (ledger_resident / effective_page_size);
1056 				pinfo->pri_ref_count = 1;
1057 				pinfo->pri_shadow_depth = 0;
1058 				pinfo->pri_share_mode = SM_PRIVATE;
1059 				pinfo->pri_private_pages_resident =
1060 				    (uint32_t) (ledger_resident / effective_page_size);
1061 				pinfo->pri_shared_pages_resident = 0;
1062 				pinfo->pri_obj_id = VM_OBJECT_ID_FAKE(map, task_ledgers.purgeable_nonvolatile);
1063 				pinfo->pri_address = address;
1064 				pinfo->pri_size =
1065 				    (uint64_t) (ledger_resident + ledger_compressed);
1066 				pinfo->pri_depth = 0;
1067 
1068 				vm_map_unlock_read(map);
1069 				vm_map_deallocate(map);
1070 				vmlp_api_end(FILL_PROCREGIONINFO, 1);
1071 				return 1;
1072 			}
1073 			vm_map_unlock_read(map);
1074 			vm_map_deallocate(map);
1075 			vmlp_api_end(FILL_PROCREGIONINFO, 0);
1076 			return 0;
1077 		}
1078 	} else {
1079 		entry = tmp_entry;
1080 	}
1081 
1082 	start = entry->vme_start;
1083 	vmlp_range_event_entry(map, entry);
1084 
1085 	pinfo->pri_offset = VME_OFFSET(entry);
1086 	pinfo->pri_protection = entry->protection;
1087 	pinfo->pri_max_protection = entry->max_protection;
1088 	pinfo->pri_inheritance = entry->inheritance;
1089 	pinfo->pri_behavior = entry->behavior;
1090 	pinfo->pri_user_wired_count = entry->user_wired_count;
1091 	pinfo->pri_user_tag = VME_ALIAS(entry);
1092 
1093 	if (entry->is_sub_map) {
1094 		pinfo->pri_flags |= PROC_REGION_SUBMAP;
1095 	} else {
1096 		if (entry->is_shared) {
1097 			pinfo->pri_flags |= PROC_REGION_SHARED;
1098 		}
1099 	}
1100 
1101 
1102 	extended.protection = entry->protection;
1103 	extended.user_tag = VME_ALIAS(entry);
1104 	extended.pages_resident = 0;
1105 	extended.pages_swapped_out = 0;
1106 	extended.pages_shared_now_private = 0;
1107 	extended.pages_dirtied = 0;
1108 	extended.external_pager = 0;
1109 	extended.shadow_depth = 0;
1110 
1111 	vm_map_region_walk(map, start, entry, VME_OFFSET(entry), entry->vme_end - start, &extended, TRUE, VM_REGION_EXTENDED_INFO_COUNT);
1112 
1113 	top.private_pages_resident = 0;
1114 	top.shared_pages_resident = 0;
1115 	vm_map_region_top_walk(entry, &top);
1116 
1117 
1118 	pinfo->pri_pages_resident = extended.pages_resident;
1119 	pinfo->pri_pages_shared_now_private = extended.pages_shared_now_private;
1120 	pinfo->pri_pages_swapped_out = extended.pages_swapped_out;
1121 	pinfo->pri_pages_dirtied = extended.pages_dirtied;
1122 	pinfo->pri_ref_count = extended.ref_count;
1123 	pinfo->pri_shadow_depth = extended.shadow_depth;
1124 	pinfo->pri_share_mode = extended.share_mode;
1125 
1126 	pinfo->pri_private_pages_resident = top.private_pages_resident;
1127 	pinfo->pri_shared_pages_resident = top.shared_pages_resident;
1128 	pinfo->pri_obj_id = top.obj_id;
1129 
1130 	pinfo->pri_address = (uint64_t)start;
1131 	pinfo->pri_size = (uint64_t)(entry->vme_end - start);
1132 	pinfo->pri_depth = 0;
1133 
1134 	if ((vnodeaddr != 0) && (entry->is_sub_map == 0)) {
1135 		*vnodeaddr = (uintptr_t)0;
1136 
1137 		if (fill_vnodeinfoforaddr(entry, vnodeaddr, vid, NULL) == 0) {
1138 			vm_map_unlock_read(map);
1139 			vm_map_deallocate(map);
1140 			vmlp_api_end(FILL_PROCREGIONINFO, 1);
1141 			return 1;
1142 		}
1143 	}
1144 
1145 	vm_map_unlock_read(map);
1146 	vm_map_deallocate(map);
1147 	vmlp_api_end(FILL_PROCREGIONINFO, 1);
1148 	return 1;
1149 }
1150 
1151 int
fill_procregioninfo_onlymappedvnodes(task_t task,uint64_t arg,struct proc_regioninfo_internal * pinfo,uintptr_t * vnodeaddr,uint32_t * vid)1152 fill_procregioninfo_onlymappedvnodes(task_t task, uint64_t arg, struct proc_regioninfo_internal *pinfo, uintptr_t *vnodeaddr, uint32_t  *vid)
1153 {
1154 	vm_map_t map;
1155 	vm_map_offset_t address = (vm_map_offset_t)arg;
1156 	vm_map_entry_t          tmp_entry;
1157 	vm_map_entry_t          entry;
1158 
1159 	vmlp_api_start(FILL_PROCREGIONINFO_ONLYMAPPEDVNODES);
1160 
1161 	task_lock(task);
1162 	map = task->map;
1163 	if (map == VM_MAP_NULL) {
1164 		task_unlock(task);
1165 		vmlp_api_end(FILL_PROCREGIONINFO_ONLYMAPPEDVNODES, 0);
1166 		return 0;
1167 	}
1168 	vm_map_reference(map);
1169 	task_unlock(task);
1170 
1171 	vm_map_lock_read(map);
1172 
1173 	if (!vm_map_lookup_entry(map, address, &tmp_entry)) {
1174 		if ((entry = tmp_entry->vme_next) == vm_map_to_entry(map)) {
1175 			vm_map_unlock_read(map);
1176 			vm_map_deallocate(map);
1177 			vmlp_api_end(FILL_PROCREGIONINFO_ONLYMAPPEDVNODES, 0);
1178 			return 0;
1179 		}
1180 	} else {
1181 		entry = tmp_entry;
1182 	}
1183 
1184 	while (entry != vm_map_to_entry(map)) {
1185 		vmlp_range_event_entry(map, entry);
1186 		*vnodeaddr = 0;
1187 		*vid = 0;
1188 
1189 		if (entry->is_sub_map == 0) {
1190 			if (fill_vnodeinfoforaddr(entry, vnodeaddr, vid, NULL)) {
1191 				pinfo->pri_offset = VME_OFFSET(entry);
1192 				pinfo->pri_protection = entry->protection;
1193 				pinfo->pri_max_protection = entry->max_protection;
1194 				pinfo->pri_inheritance = entry->inheritance;
1195 				pinfo->pri_behavior = entry->behavior;
1196 				pinfo->pri_user_wired_count = entry->user_wired_count;
1197 				pinfo->pri_user_tag = VME_ALIAS(entry);
1198 
1199 				if (entry->is_shared) {
1200 					pinfo->pri_flags |= PROC_REGION_SHARED;
1201 				}
1202 
1203 				pinfo->pri_pages_resident = 0;
1204 				pinfo->pri_pages_shared_now_private = 0;
1205 				pinfo->pri_pages_swapped_out = 0;
1206 				pinfo->pri_pages_dirtied = 0;
1207 				pinfo->pri_ref_count = 0;
1208 				pinfo->pri_shadow_depth = 0;
1209 				pinfo->pri_share_mode = 0;
1210 
1211 				pinfo->pri_private_pages_resident = 0;
1212 				pinfo->pri_shared_pages_resident = 0;
1213 				pinfo->pri_obj_id = 0;
1214 
1215 				pinfo->pri_address = (uint64_t)entry->vme_start;
1216 				pinfo->pri_size = (uint64_t)(entry->vme_end - entry->vme_start);
1217 				pinfo->pri_depth = 0;
1218 
1219 				vm_map_unlock_read(map);
1220 				vm_map_deallocate(map);
1221 				vmlp_api_end(FILL_PROCREGIONINFO_ONLYMAPPEDVNODES, 1);
1222 				return 1;
1223 			}
1224 		}
1225 
1226 		/* Keep searching for a vnode-backed mapping */
1227 		entry = entry->vme_next;
1228 	}
1229 
1230 	vm_map_unlock_read(map);
1231 	vm_map_deallocate(map);
1232 	vmlp_api_end(FILL_PROCREGIONINFO_ONLYMAPPEDVNODES, 0);
1233 	return 0;
1234 }
1235 
1236 extern int vnode_get(struct vnode *vp);
1237 int
task_find_region_details(task_t task,vm_map_offset_t offset,find_region_details_options_t options,uintptr_t * vp_p,uint32_t * vid_p,bool * is_map_shared_p,uint64_t * start_p,uint64_t * len_p)1238 task_find_region_details(
1239 	task_t task,
1240 	vm_map_offset_t offset,
1241 	find_region_details_options_t options,
1242 	uintptr_t *vp_p,
1243 	uint32_t *vid_p,
1244 	bool *is_map_shared_p,
1245 	uint64_t *start_p,
1246 	uint64_t *len_p)
1247 {
1248 	vm_map_t        map;
1249 	vm_map_entry_t  entry;
1250 	int             rc;
1251 
1252 	vmlp_api_start(TASK_FIND_REGION_DETAILS);
1253 
1254 	rc = 0;
1255 	*vp_p = 0;
1256 	*vid_p = 0;
1257 	*is_map_shared_p = false;
1258 	*start_p = 0;
1259 	*len_p = 0;
1260 	if (options & ~FIND_REGION_DETAILS_OPTIONS_ALL) {
1261 		vmlp_api_end(TASK_FIND_REGION_DETAILS, 0);
1262 		return 0;
1263 	}
1264 
1265 	task_lock(task);
1266 	map = task->map;
1267 	if (map == VM_MAP_NULL) {
1268 		task_unlock(task);
1269 		vmlp_api_end(TASK_FIND_REGION_DETAILS, 0);
1270 		return 0;
1271 	}
1272 	vm_map_reference(map);
1273 	task_unlock(task);
1274 
1275 	vm_map_lock_read(map);
1276 	if (!vm_map_lookup_entry(map, offset, &entry)) {
1277 		if (options & FIND_REGION_DETAILS_AT_OFFSET) {
1278 			/* no mapping at this offset */
1279 			goto ret;
1280 		}
1281 		/* check next entry */
1282 		entry = entry->vme_next;
1283 		if (entry == vm_map_to_entry(map)) {
1284 			/* no next entry */
1285 			goto ret;
1286 		}
1287 	}
1288 
1289 	for (;
1290 	    entry != vm_map_to_entry(map);
1291 	    entry = entry->vme_next) {
1292 		vmlp_range_event_entry(map, entry);
1293 
1294 		if (entry->is_sub_map) {
1295 			/* fallthru to check next entry */
1296 		} else if (fill_vnodeinfoforaddr(entry, vp_p, vid_p, is_map_shared_p)) {
1297 			if ((options & FIND_REGION_DETAILS_GET_VNODE) &&
1298 			    vnode_get((struct vnode *)*vp_p)) {
1299 				/* tried but could not get an iocount */
1300 				*vp_p = 0;
1301 				*vid_p = 0;
1302 				if (options & FIND_REGION_DETAILS_AT_OFFSET) {
1303 					/* done */
1304 					break;
1305 				}
1306 				/* check next entry */
1307 				continue;
1308 			}
1309 			*start_p = entry->vme_start;
1310 			*len_p = entry->vme_end - entry->vme_start;
1311 			rc = 1; /* success */
1312 			break;
1313 		}
1314 		if (options & FIND_REGION_DETAILS_AT_OFFSET) {
1315 			/* no file mapping at this offset: done */
1316 			break;
1317 		}
1318 		/* check next entry */
1319 	}
1320 
1321 ret:
1322 	vm_map_unlock_read(map);
1323 	vm_map_deallocate(map);
1324 	vmlp_api_end(TASK_FIND_REGION_DETAILS, rc);
1325 	return rc;
1326 }
1327 
1328 static int
fill_vnodeinfoforaddr(vm_map_entry_t entry,uintptr_t * vnodeaddr,uint32_t * vid,bool * is_map_shared)1329 fill_vnodeinfoforaddr(
1330 	vm_map_entry_t                  entry,
1331 	uintptr_t * vnodeaddr,
1332 	uint32_t * vid,
1333 	bool *is_map_shared)
1334 {
1335 	vm_object_t     top_object, object;
1336 	memory_object_t memory_object;
1337 	memory_object_pager_ops_t pager_ops;
1338 	kern_return_t   kr;
1339 	int             shadow_depth;
1340 
1341 
1342 	if (entry->is_sub_map) {
1343 		return 0;
1344 	} else {
1345 		/*
1346 		 * The last object in the shadow chain has the
1347 		 * relevant pager information.
1348 		 */
1349 		top_object = VME_OBJECT(entry);
1350 		if (top_object == VM_OBJECT_NULL) {
1351 			object = VM_OBJECT_NULL;
1352 			shadow_depth = 0;
1353 		} else {
1354 			vm_object_lock(top_object);
1355 			for (object = top_object, shadow_depth = 0;
1356 			    object->shadow != VM_OBJECT_NULL;
1357 			    object = object->shadow, shadow_depth++) {
1358 				vm_object_lock(object->shadow);
1359 				vm_object_unlock(object);
1360 			}
1361 		}
1362 	}
1363 
1364 	if (object == VM_OBJECT_NULL) {
1365 		return 0;
1366 	} else if (object->internal) {
1367 		vm_object_unlock(object);
1368 		return 0;
1369 	} else if (!object->pager_ready ||
1370 	    object->terminating ||
1371 	    !object->alive ||
1372 	    object->pager == NULL) {
1373 		vm_object_unlock(object);
1374 		return 0;
1375 	} else {
1376 		memory_object = object->pager;
1377 		pager_ops = memory_object->mo_pager_ops;
1378 		if (pager_ops == &vnode_pager_ops) {
1379 			kr = vnode_pager_get_object_vnode(
1380 				memory_object,
1381 				vnodeaddr, vid);
1382 			if (kr != KERN_SUCCESS) {
1383 				vm_object_unlock(object);
1384 				return 0;
1385 			}
1386 		} else {
1387 			vm_object_unlock(object);
1388 			return 0;
1389 		}
1390 	}
1391 	if (is_map_shared) {
1392 		*is_map_shared = (shadow_depth == 0);
1393 	}
1394 	vm_object_unlock(object);
1395 	return 1;
1396 }
1397 
1398 kern_return_t
vnode_pager_get_object_vnode(memory_object_t mem_obj,uintptr_t * vnodeaddr,uint32_t * vid)1399 vnode_pager_get_object_vnode(
1400 	memory_object_t         mem_obj,
1401 	uintptr_t * vnodeaddr,
1402 	uint32_t * vid)
1403 {
1404 	vnode_pager_t   vnode_object;
1405 
1406 	vnode_object = vnode_pager_lookup(mem_obj);
1407 	if (vnode_object->vnode_handle) {
1408 		*vnodeaddr = (uintptr_t)vnode_object->vnode_handle;
1409 		*vid = (uint32_t)vnode_vid((void *)vnode_object->vnode_handle);
1410 
1411 		return KERN_SUCCESS;
1412 	}
1413 
1414 	return KERN_FAILURE;
1415 }
1416 
1417 #if CONFIG_IOSCHED
1418 kern_return_t
vnode_pager_get_object_devvp(memory_object_t mem_obj,uintptr_t * devvp)1419 vnode_pager_get_object_devvp(
1420 	memory_object_t         mem_obj,
1421 	uintptr_t               *devvp)
1422 {
1423 	struct vnode    *vp;
1424 	uint32_t        vid;
1425 
1426 	if (vnode_pager_get_object_vnode(mem_obj, (uintptr_t *)&vp, (uint32_t *)&vid) != KERN_SUCCESS) {
1427 		return KERN_FAILURE;
1428 	}
1429 	*devvp = (uintptr_t)vnode_mountdevvp(vp);
1430 	if (*devvp) {
1431 		return KERN_SUCCESS;
1432 	}
1433 	return KERN_FAILURE;
1434 }
1435 #endif
1436 
1437 /*
1438  * Find the underlying vnode object for the given vm_map_entry.  If found, return with the
1439  * object locked, otherwise return NULL with nothing locked.
1440  */
1441 
1442 vm_object_t
find_vnode_object(vm_map_entry_t entry)1443 find_vnode_object(
1444 	vm_map_entry_t  entry
1445 	)
1446 {
1447 	vm_object_t                     top_object, object;
1448 	memory_object_t                 memory_object;
1449 	memory_object_pager_ops_t       pager_ops;
1450 
1451 	if (!entry->is_sub_map) {
1452 		/*
1453 		 * The last object in the shadow chain has the
1454 		 * relevant pager information.
1455 		 */
1456 
1457 		top_object = VME_OBJECT(entry);
1458 
1459 		if (top_object) {
1460 			vm_object_lock(top_object);
1461 
1462 			for (object = top_object; object->shadow != VM_OBJECT_NULL; object = object->shadow) {
1463 				vm_object_lock(object->shadow);
1464 				vm_object_unlock(object);
1465 			}
1466 
1467 			if (object &&
1468 			    !object->internal &&
1469 			    object->pager_ready &&
1470 			    !object->terminating &&
1471 			    object->alive &&
1472 			    object->pager != NULL) {
1473 				memory_object = object->pager;
1474 				pager_ops = memory_object->mo_pager_ops;
1475 
1476 				/*
1477 				 * If this object points to the vnode_pager_ops, then we found what we're
1478 				 * looking for.  Otherwise, this vm_map_entry doesn't have an underlying
1479 				 * vnode and so we fall through to the bottom and return NULL.
1480 				 */
1481 
1482 				if (pager_ops == &vnode_pager_ops) {
1483 					return object;          /* we return with the object locked */
1484 				}
1485 			}
1486 
1487 			vm_object_unlock(object);
1488 		}
1489 	}
1490 
1491 	return VM_OBJECT_NULL;
1492 }
1493