1 /* $NetBSD: db_memrw.c,v 1.4 2001/05/18 20:38:27 matt Exp $ */
2 /* $OpenBSD: db_memrw.c,v 1.7 2024/02/23 18:19:03 cheloha Exp $ */
3
4 /*
5 * Mach Operating System
6 * Copyright (c) 1992 Carnegie Mellon University
7 * All Rights Reserved.
8 *
9 * Permission to use, copy, modify and distribute this software and its
10 * documentation is hereby granted, provided that both the copyright
11 * notice and this permission notice appear in all copies of the
12 * software, derivative works or modified versions, and any portions
13 * thereof, and that both notices appear in supporting documentation.
14 *
15 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
16 * CONDITION. CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND FOR
17 * ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
18 *
19 * Carnegie Mellon requests users of this software to return to
20 *
21 * Software Distribution Coordinator or Software.Distribution@CS.CMU.EDU
22 * School of Computer Science
23 * Carnegie Mellon University
24 * Pittsburgh PA 15213-3890
25 *
26 * any improvements or extensions that they make and grant Carnegie Mellon
27 * the rights to redistribute these changes.
28 */
29
30 /*
31 * Interface to the debugger for virtual memory read/write.
32 * This is a simple version for kernels with writable text.
33 * For an example of read-only kernel text, see the file:
34 * sys/arch/sun3/sun3/db_memrw.c
35 *
36 * ALERT! If you want to access device registers with a
37 * specific size, then the read/write functions have to
38 * make sure to do the correct sized pointer access.
39 */
40
41 #include <sys/param.h>
42 #include <sys/proc.h>
43 #include <sys/systm.h>
44
45 #include <uvm/uvm_extern.h>
46
47 #include <machine/db_machdep.h>
48 #include <machine/pcb.h>
49
50 #include <ddb/db_access.h>
51
52 /*
53 * Read bytes from kernel address space for debugger.
54 */
55 void
db_read_bytes(vaddr_t addr,size_t size,void * datap)56 db_read_bytes(vaddr_t addr, size_t size, void *datap)
57 {
58 char *data = datap, *src = (char *)addr;
59 faultbuf env;
60 faultbuf *old_onfault = curpcb->pcb_onfault;
61 if (setfault(&env)) {
62 curpcb->pcb_onfault = old_onfault;
63 return;
64 }
65
66 if (size == 4) {
67 *((int *)data) = *((int *)src);
68 } else if (size == 2) {
69 *((short *)data) = *((short *)src);
70 } else {
71 while (size > 0) {
72 --size;
73 *data++ = *src++;
74 }
75 }
76 curpcb->pcb_onfault = old_onfault;
77 }
78
79 /*
80 * Write bytes to kernel address space for debugger.
81 */
82 void
db_write_bytes(vaddr_t addr,size_t size,void * datap)83 db_write_bytes(vaddr_t addr, size_t size, void *datap)
84 {
85 char *data = datap, *dst = (char *)addr;
86 faultbuf env;
87 faultbuf *old_onfault = curpcb->pcb_onfault;
88
89 if (setfault(&env)) {
90 curpcb->pcb_onfault = old_onfault;
91 return;
92 }
93
94 if (size == 4) {
95 *((int *)dst) = *((int *)data);
96 } else if (size == 2) {
97 *((short *)dst) = *((short *)data);
98 } else {
99 while (size > 0) {
100 --size;
101 *dst++ = *data++;
102 }
103 }
104 syncicache((void *)addr, size);
105 curpcb->pcb_onfault = old_onfault;
106 }
107
108