xref: /freebsd/sys/fs/procfs/procfs_dbregs.c (revision 7660b554bc59a07be0431c17e0e33815818baa69)
1 /*-
2  * Copyright (c) 1999 Brian Scott Dean, brdean@unx.sas.com.
3  *                    All rights reserved.
4  *
5  * This code is derived from software contributed to Berkeley by
6  * Jan-Simon Pendry under the following copyrights and conditions:
7  *
8  * Copyright (c) 1993 Jan-Simon Pendry
9  * Copyright (c) 1993
10  *	The Regents of the University of California.  All rights reserved.
11  *
12  * This code is derived from software contributed to Berkeley by
13  * Jan-Simon Pendry.
14  *
15  * Redistribution and use in source and binary forms, with or without
16  * modification, are permitted provided that the following conditions
17  * are met:
18  * 1. Redistributions of source code must retain the above copyright
19  *    notice, this list of conditions and the following disclaimer.
20  * 2. Redistributions in binary form must reproduce the above copyright
21  *    notice, this list of conditions and the following disclaimer in the
22  *    documentation and/or other materials provided with the distribution.
23  * 3. All advertising materials mentioning features or use of this software
24  *    must display the following acknowledgement:
25  *	This product includes software developed by the University of
26  *	California, Berkeley and its contributors.
27  * 4. Neither the name of the University nor the names of its contributors
28  *    may be used to endorse or promote products derived from this software
29  *    without specific prior written permission.
30  *
31  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
32  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
33  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
34  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
35  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
36  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
37  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
38  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
39  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
40  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
41  * SUCH DAMAGE.
42  *
43  *	From: @(#)procfs_regs.c	8.4 (Berkeley) 6/15/94
44  *
45  * From:
46  *	$Id: procfs_regs.c,v 3.2 1993/12/15 09:40:17 jsp Exp $
47  * $FreeBSD$
48  */
49 
50 #include <sys/param.h>
51 #include <sys/systm.h>
52 #include <sys/lock.h>
53 #include <sys/mutex.h>
54 #include <sys/proc.h>
55 #include <sys/ptrace.h>
56 #include <sys/uio.h>
57 
58 #include <machine/reg.h>
59 
60 #include <fs/pseudofs/pseudofs.h>
61 #include <fs/procfs/procfs.h>
62 
63 int
64 procfs_doprocdbregs(PFS_FILL_ARGS)
65 {
66 	int error;
67 	struct dbreg r;
68 	char *kv;
69 	int kl;
70 
71 	PROC_LOCK(p);
72 	if (p_candebug(td, p) != 0) {
73 		PROC_UNLOCK(p);
74 		return (EPERM);
75 	}
76 	kl = sizeof(r);
77 	kv = (char *) &r;
78 
79 	kv += uio->uio_offset;
80 	kl -= uio->uio_offset;
81 	if (kl > uio->uio_resid)
82 		kl = uio->uio_resid;
83 
84 	_PHOLD(p);
85 	if (kl < 0)
86 		error = EINVAL;
87 	else
88 		/* XXXKSE: */
89 		error = proc_read_dbregs(FIRST_THREAD_IN_PROC(p), &r);
90 	if (error == 0) {
91 		PROC_UNLOCK(p);
92 		error = uiomove(kv, kl, uio);
93 		PROC_LOCK(p);
94 	}
95 	if (error == 0 && uio->uio_rw == UIO_WRITE) {
96 		if (!P_SHOULDSTOP(p)) /* XXXKSE should be P_TRACED? */
97 			error = EBUSY;
98 		else
99 			/* XXXKSE: */
100 			error = proc_write_dbregs(FIRST_THREAD_IN_PROC(p), &r);
101 	}
102 	_PRELE(p);
103 	PROC_UNLOCK(p);
104 
105 	uio->uio_offset = 0;
106 	return (error);
107 }
108