xref: /xnu-11417.140.69/osfmk/vm/vm_memtag.c (revision 43a90889846e00bfb5cf1d255cdc0a701a1e05a4)
1 /*
2  * Copyright (c) 2024 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,
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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.
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18  * The Original Code and all software distributed under the License are
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20  * EXPRESS OR IMPLIED, AND APPLE HEREBY DISCLAIMS ALL SUCH WARRANTIES,
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27  */
28 
29 #include <vm/vm_memtag.h>
30 
31 #if defined(ENABLE_MEMTAG_MANIPULATION_API)
32 #include <vm/vm_map_xnu.h>
33 #include <vm/pmap.h>
34 
35 /* Do the right canonicalization based on the vm_map the address belongs to */
36 vm_map_address_t
vm_memtag_canonicalize(vm_map_t map,vm_map_address_t addr)37 vm_memtag_canonicalize(vm_map_t map, vm_map_address_t addr)
38 {
39 	assert(map);
40 
41 	/* With no pmap assigned we cannot make a decision. Leave the address as is */
42 	if (map->pmap == NULL) {
43 		return addr;
44 	}
45 
46 	/* NULL is a frequent enough special case. */
47 	if (addr == (vm_map_address_t)NULL) {
48 		return addr;
49 	}
50 
51 	return (map->pmap == kernel_pmap) ?
52 	       (vm_map_address_t)vm_memtag_canonicalize_kernel(addr) :
53 	       (vm_map_address_t)vm_memtag_canonicalize_user(addr);
54 }
55 #endif /* ENABLE_MEMTAG_MANIPULATION_API */
56