xref: /freebsd/sys/kern/p1003_1b.c (revision 29b2efeb6bbce8f8def354194ef4b45fbeb241a0)
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  * $FreeBSD$
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 
52 MALLOC_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  */
87 int 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  */
118 int
119 syscall_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 
135 static int sched_attach(void)
136 {
137 	return 0;
138 }
139 
140 SYSCALL_NOT_PRESENT_GEN(sched_setparam)
141 SYSCALL_NOT_PRESENT_GEN(sched_getparam)
142 SYSCALL_NOT_PRESENT_GEN(sched_setscheduler)
143 SYSCALL_NOT_PRESENT_GEN(sched_getscheduler)
144 SYSCALL_NOT_PRESENT_GEN(sched_yield)
145 SYSCALL_NOT_PRESENT_GEN(sched_get_priority_max)
146 SYSCALL_NOT_PRESENT_GEN(sched_get_priority_min)
147 SYSCALL_NOT_PRESENT_GEN(sched_rr_get_interval)
148 
149 #else
150 
151 /* Configured in kernel version:
152  */
153 static struct ksched *ksched;
154 
155 static 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 
165 int 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 
182 int 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 }
198 int 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 }
215 int 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 }
226 int sched_yield(struct proc *p,
227 	struct sched_yield_args *uap)
228 {
229 	return ksched_yield(&p->p_retval[0], ksched);
230 }
231 int 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 }
237 int 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 }
243 int 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 
259 static void p31binit(void *notused)
260 {
261 	(void) sched_attach();
262 	p31b_setcfg(CTL_P1003_1B_PAGESIZE, PAGE_SIZE);
263 }
264 
265 SYSINIT(p31b, SI_SUB_P1003_1B, SI_ORDER_FIRST, p31binit, NULL);
266