p1003_1b.c revision 76316 
1/*
2 * Copyright (c) 1996, 1997, 1998
3 *	HD Associates, Inc.  All rights reserved.
4 *
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
7 * are met:
8 * 1. Redistributions of source code must retain the above copyright
9 *    notice, this list of conditions and the following disclaimer.
10 * 2. Redistributions in binary form must reproduce the above copyright
11 *    notice, this list of conditions and the following disclaimer in the
12 *    documentation and/or other materials provided with the distribution.
13 * 3. All advertising materials mentioning features or use of this software
14 *    must display the following acknowledgement:
15 *	This product includes software developed by HD Associates, Inc
16 * 4. Neither the name of the author nor the names of any co-contributors
17 *    may be used to endorse or promote products derived from this software
18 *    without specific prior written permission.
19 *
20 * THIS SOFTWARE IS PROVIDED BY HD ASSOCIATES AND CONTRIBUTORS ``AS IS'' AND
21 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
22 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
23 * ARE DISCLAIMED.  IN NO EVENT SHALL HD ASSOCIATES OR CONTRIBUTORS BE LIABLE
24 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
25 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
26 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
27 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
28 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
29 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
30 * SUCH DAMAGE.
31 *
32 * $FreeBSD: head/sys/kern/p1003_1b.c 76316 2001-05-06 16:15:42Z rwatson $
33 */
34
35/* p1003_1b: Real Time common code.
36 */
37
38#include <sys/param.h>
39#include <sys/systm.h>
40#include <sys/kernel.h>
41#include <sys/lock.h>
42#include <sys/module.h>
43#include <sys/mutex.h>
44#include <sys/proc.h>
45#include <sys/sysctl.h>
46#include <sys/sysent.h>
47#include <sys/syslog.h>
48#include <sys/sysproto.h>
49
50#include <posix4/posix4.h>
51
52MALLOC_DEFINE(M_P31B, "p1003.1b", "Posix 1003.1B");
53
54/* p31b_proc: Return a proc struct corresponding to a pid to operate on.
55 *
56 * Enforce permission policy.
57 *
58 * The policy is the same as for sending signals except there
59 * is no notion of process groups.
60 *
61 * pid == 0 means my process.
62 *
63 * This is disabled until I've got a permission gate in again:
64 * only root can do this.
65 */
66
67#if 0
68/*
69 * This is stolen from CANSIGNAL in kern_sig:
70 *
71 * Can process p, with pcred pc, do "write flavor" operations to process q?
72 */
73#define CAN_AFFECT(p, q) \
74	(!suser_xxx(NULL, p, PRISON_ROOT) || \
75	    (p)->p_cred->pc_ruid == (q)->p_cred->p_ruid || \
76	    (p)->p_ucred->cr_uid == (q)->p_cred->p_ruid || \
77	    (p)->p_cred->pc_ruid == (q)->p_ucred->cr_uid || \
78	    (p)->p_ucred->cr_uid == (q)->p_ucred->cr_uid)
79#else
80#define CAN_AFFECT(p, q) (!suser_xxx(NULL, p, PRISON_ROOT))
81#endif
82
83/*
84 * p31b_proc: Look up a proc from a PID.  If proc is 0 it is
85 * my own proc.
86 */
87int p31b_proc(struct proc *p, pid_t pid, struct proc **pp)
88{
89	int ret = 0;
90	struct proc *other_proc = 0;
91
92	if (pid == 0) {
93		other_proc = p;
94		PROC_LOCK(p);
95	} else
96		other_proc = pfind(pid);
97
98	if (other_proc)
99	{
100		/* Enforce permission policy.
101		 */
102		if (CAN_AFFECT(p, other_proc))
103			*pp = other_proc;
104		else
105			ret = EPERM;
106		PROC_UNLOCK(other_proc);
107	}
108	else
109		ret = ESRCH;
110
111	return ret;
112}
113
114/* The system calls return ENOSYS if an entry is called that is
115 * not run-time supported.  I am also logging since some programs
116 * start to use this when they shouldn't.  That will be removed if annoying.
117 */
118int
119syscall_not_present(struct proc *p, const char *s, struct nosys_args *uap)
120{
121	log(LOG_ERR, "cmd %s pid %d tried to use non-present %s\n",
122			p->p_comm, p->p_pid, s);
123
124	/* a " return nosys(p, uap); " here causes a core dump.
125	 */
126
127	return ENOSYS;
128}
129
130#if !defined(_KPOSIX_PRIORITY_SCHEDULING)
131
132/* Not configured but loadable via a module:
133 */
134
135static int sched_attach(void)
136{
137	return 0;
138}
139
140SYSCALL_NOT_PRESENT_GEN(sched_setparam)
141SYSCALL_NOT_PRESENT_GEN(sched_getparam)
142SYSCALL_NOT_PRESENT_GEN(sched_setscheduler)
143SYSCALL_NOT_PRESENT_GEN(sched_getscheduler)
144SYSCALL_NOT_PRESENT_GEN(sched_yield)
145SYSCALL_NOT_PRESENT_GEN(sched_get_priority_max)
146SYSCALL_NOT_PRESENT_GEN(sched_get_priority_min)
147SYSCALL_NOT_PRESENT_GEN(sched_rr_get_interval)
148
149#else
150
151/* Configured in kernel version:
152 */
153static struct ksched *ksched;
154
155static int sched_attach(void)
156{
157	int ret = ksched_attach(&ksched);
158
159	if (ret == 0)
160		p31b_setcfg(CTL_P1003_1B_PRIORITY_SCHEDULING, 1);
161
162	return ret;
163}
164
165int sched_setparam(struct proc *p,
166	struct sched_setparam_args *uap)
167{
168	int e;
169
170	struct sched_param sched_param;
171	copyin(uap->param, &sched_param, sizeof(sched_param));
172
173	(void) (0
174	|| (e = p31b_proc(p, uap->pid, &p))
175	|| (e = ksched_setparam(&p->p_retval[0], ksched, p,
176		(const struct sched_param *)&sched_param))
177	);
178
179	return e;
180}
181
182int sched_getparam(struct proc *p,
183	struct sched_getparam_args *uap)
184{
185	int e;
186	struct sched_param sched_param;
187
188	(void) (0
189	|| (e = p31b_proc(p, uap->pid, &p))
190	|| (e = ksched_getparam(&p->p_retval[0], ksched, p, &sched_param))
191	);
192
193	if (!e)
194		copyout(&sched_param, uap->param, sizeof(sched_param));
195
196	return e;
197}
198int sched_setscheduler(struct proc *p,
199	struct sched_setscheduler_args *uap)
200{
201	int e;
202
203	struct sched_param sched_param;
204	copyin(uap->param, &sched_param, sizeof(sched_param));
205
206	(void) (0
207	|| (e = p31b_proc(p, uap->pid, &p))
208	|| (e = ksched_setscheduler(&p->p_retval[0],
209	ksched, p, uap->policy,
210		(const struct sched_param *)&sched_param))
211	);
212
213	return e;
214}
215int sched_getscheduler(struct proc *p,
216	struct sched_getscheduler_args *uap)
217{
218	int e;
219	(void) (0
220	|| (e = p31b_proc(p, uap->pid, &p))
221	|| (e = ksched_getscheduler(&p->p_retval[0], ksched, p))
222	);
223
224	return e;
225}
226int sched_yield(struct proc *p,
227	struct sched_yield_args *uap)
228{
229	return ksched_yield(&p->p_retval[0], ksched);
230}
231int sched_get_priority_max(struct proc *p,
232	struct sched_get_priority_max_args *uap)
233{
234	return ksched_get_priority_max(&p->p_retval[0],
235	ksched, uap->policy);
236}
237int sched_get_priority_min(struct proc *p,
238	struct sched_get_priority_min_args *uap)
239{
240	return ksched_get_priority_min(&p->p_retval[0],
241	ksched, uap->policy);
242}
243int sched_rr_get_interval(struct proc *p,
244	struct sched_rr_get_interval_args *uap)
245{
246	int e;
247
248	(void) (0
249	|| (e = p31b_proc(p, uap->pid, &p))
250	|| (e = ksched_rr_get_interval(&p->p_retval[0], ksched,
251	p, uap->interval))
252	);
253
254	return e;
255}
256
257#endif
258
259static void p31binit(void *notused)
260{
261	(void) sched_attach();
262	p31b_setcfg(CTL_P1003_1B_PAGESIZE, PAGE_SIZE);
263}
264
265SYSINIT(p31b, SI_SUB_P1003_1B, SI_ORDER_FIRST, p31binit, NULL);
266