xref: /dragonfly/sys/vfs/procfs/procfs_regs.c (revision 2b3f93ea)
1 /*
2  * Copyright (c) 1993 Jan-Simon Pendry
3  * Copyright (c) 1993
4  *	The Regents of the University of California.  All rights reserved.
5  *
6  * This code is derived from software contributed to Berkeley by
7  * Jan-Simon Pendry.
8  *
9  * Redistribution and use in source and binary forms, with or without
10  * modification, are permitted provided that the following conditions
11  * are met:
12  * 1. Redistributions of source code must retain the above copyright
13  *    notice, this list of conditions and the following disclaimer.
14  * 2. Redistributions in binary form must reproduce the above copyright
15  *    notice, this list of conditions and the following disclaimer in the
16  *    documentation and/or other materials provided with the distribution.
17  * 3. Neither the name of the University nor the names of its contributors
18  *    may be used to endorse or promote products derived from this software
19  *    without specific prior written permission.
20  *
21  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
22  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
23  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
24  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
25  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
26  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
27  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
28  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
29  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
30  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
31  * SUCH DAMAGE.
32  *
33  *	@(#)procfs_regs.c	8.4 (Berkeley) 6/15/94
34  *
35  * From:
36  * $FreeBSD: src/sys/miscfs/procfs/procfs_regs.c,v 1.10.2.3 2002/01/22 17:22:59 nectar Exp $
37  */
38 
39 #include <sys/param.h>
40 #include <sys/uio.h>
41 #include <sys/proc.h>
42 #include <sys/caps.h>
43 #include <sys/vnode.h>
44 #include <sys/reg.h>
45 #include <vfs/procfs/procfs.h>
46 #include <vm/vm.h>
47 #include <vm/vm_extern.h>
48 
49 int
procfs_doregs(struct proc * curp,struct lwp * lp,struct pfsnode * pfs,struct uio * uio)50 procfs_doregs(struct proc *curp, struct lwp *lp, struct pfsnode *pfs,
51 	      struct uio *uio)
52 {
53 	struct proc *p = lp->lwp_proc;
54 	int error;
55 	struct reg r;
56 
57 	/* Can't trace a process that's currently exec'ing. */
58 	if ((p->p_flags & P_INEXEC) != 0)
59 		return EAGAIN;
60 	if (!CHECKIO(curp, p) || p_trespass(curp->p_ucred, p->p_ucred))
61 		return EPERM;
62 
63 	LWPHOLD(lp);
64 	error = procfs_read_regs(lp, &r);
65 	if (error == 0)
66 		error = uiomove_frombuf(&r, sizeof(r), uio);
67 	if (error == 0 && uio->uio_rw == UIO_WRITE) {
68 		if (p->p_stat != SSTOP)
69 			error = EBUSY;
70 		else
71 			error = procfs_write_regs(lp, &r);
72 	}
73 	LWPRELE(lp);
74 	uio->uio_offset = 0;
75 
76 	return (error);
77 }
78 
79 int
procfs_validregs(struct lwp * lp)80 procfs_validregs(struct lwp *lp)
81 {
82 	return ((lp->lwp_proc->p_flags & P_SYSTEM) == 0);
83 }
84