xref: /dragonfly/lib/libkvm/kvm_vm_map.c (revision de78d61c)
1 /*
2  * Copyright (c) 2019 The DragonFly Project.  All rights reserved.
3  *
4  * This code is derived from software contributed to The DragonFly Project
5  * by Matthew Dillon <dillon@dragonflybsd.org>
6  *
7  * Redistribution and use in source and binary forms, with or without
8  * modification, are permitted provided that the following conditions
9  * are met:
10  *
11  * 1. Redistributions of source code must retain the above copyright
12  *    notice, this list of conditions and the following disclaimer.
13  * 2. Redistributions in binary form must reproduce the above copyright
14  *    notice, this list of conditions and the following disclaimer in
15  *    the documentation and/or other materials provided with the
16  *    distribution.
17  * 3. Neither the name of The DragonFly Project nor the names of its
18  *    contributors may be used to endorse or promote products derived
19  *    from this software without specific, prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
22  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
23  * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
24  * FOR A PARTICULAR PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE
25  * COPYRIGHT HOLDERS OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
26  * INCIDENTAL, SPECIAL, EXEMPLARY OR CONSEQUENTIAL DAMAGES (INCLUDING,
27  * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
28  * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
29  * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
30  * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
31  * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
32  * SUCH DAMAGE.
33  */
34 
35 /*
36  * Useful helper functions for vm_map_t parsing.
37  */
38 
39 #include <sys/user.h>
40 #include <sys/param.h>
41 #include <vm/vm.h>
42 #include <vm/vm_map.h>
43 
44 #include "kvm.h"
45 
46 static int
47 kreadent(kvm_t *kd, const void *kaddr, vm_map_entry_t copy)
48 {
49 	size_t nb;
50 
51 	nb = sizeof(*copy);
52 
53 	if (kvm_read(kd, (u_long)kaddr, (char *)copy, nb) == (ssize_t)nb)
54 		return 1;
55 
56 	return 0;
57 }
58 
59 /*
60  * Find and read first vm_map entry.
61  */
62 vm_map_entry_t
63 kvm_vm_map_entry_first(kvm_t *kd, vm_map_t map, vm_map_entry_t copy)
64 {
65 	vm_map_entry_t ken;
66 
67 	ken = map->rb_root.rbh_root;
68 	if (ken == NULL)
69 		return NULL;
70 	if (!kreadent(kd, ken, copy))
71 		return NULL;
72 	while (copy->rb_entry.rbe_left) {
73 		ken = copy->rb_entry.rbe_left;
74 		if (!kreadent(kd, ken, copy))
75 			return NULL;
76 	}
77 	return ken;
78 }
79 
80 /*
81  * Find and read next vm_map entry.
82  */
83 vm_map_entry_t
84 kvm_vm_map_entry_next(kvm_t *kd, vm_map_entry_t ken, vm_map_entry_t copy)
85 {
86 	vm_map_entry_t ken2;
87 
88 	if (copy->rb_entry.rbe_right) {
89 		ken = copy->rb_entry.rbe_right;
90 		if (!kreadent(kd, ken, copy))
91 			return NULL;
92 		while (copy->rb_entry.rbe_left) {
93 			ken = copy->rb_entry.rbe_left;
94 			if (!kreadent(kd, ken, copy))
95 				return NULL;
96 		}
97 	} else {
98 		if ((ken2 = copy->rb_entry.rbe_parent) == NULL)
99 			return NULL;
100 		if (!kreadent(kd, ken2, copy))
101 			return NULL;
102 		if (ken == copy->rb_entry.rbe_left) {
103 			ken = ken2;
104 		} else {
105 			while (ken == copy->rb_entry.rbe_right) {
106 				ken = ken2;
107 				ken2 = copy->rb_entry.rbe_parent;
108 				if (!kreadent(kd, ken2, copy))
109 					return NULL;
110 			}
111 			ken = ken2;
112 		}
113 	}
114 	return ken;
115 }
116