1 /* $OpenBSD: kern_proc.c,v 1.18 2004/01/29 17:19:42 millert Exp $ */
2 /* + 1.40.4.1 */
3 /* $NetBSD: kern_proc.c,v 1.14 1996/02/09 18:59:41 christos Exp $ */
4
5 /*
6 * Copyright (c) 1982, 1986, 1989, 1991, 1993
7 * The Regents of the University of California. All rights reserved.
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 * @(#)kern_proc.c 8.4 (Berkeley) 1/4/94
34 */
35
36 #include <sys/param.h>
37 #include <sys/systm.h>
38 #include <sys/kernel.h>
39 #include <sys/proc.h>
40 #include <sys/buf.h>
41 #include <sys/acct.h>
42 #include <sys/wait.h>
43 #include <sys/file.h>
44 #include <ufs/ufs/quota.h>
45 #include <sys/uio.h>
46 #include <sys/malloc.h>
47 #include <sys/mbuf.h>
48 #include <sys/ioctl.h>
49 #include <sys/tty.h>
50 #include <sys/signalvar.h>
51 #include <sys/pool.h>
52
53 #define UIHASH(uid) (&uihashtbl[(uid) & uihash])
54 LIST_HEAD(uihashhead, uidinfo) *uihashtbl;
55 u_long uihash; /* size of hash table - 1 */
56
57 /*
58 * Other process lists
59 */
60 struct pidhashhead *pidhashtbl;
61 u_long pidhash;
62 struct pgrphashhead *pgrphashtbl;
63 u_long pgrphash;
64 struct proclist allproc;
65 struct proclist zombproc;
66
67 struct pool proc_pool;
68 struct pool rusage_pool;
69 struct pool ucred_pool;
70 struct pool pgrp_pool;
71 struct pool session_pool;
72 struct pool pcred_pool;
73
74 /*
75 * Locking of this proclist is special; it's accessed in a
76 * critical section of process exit, and thus locking it can't
77 * modify interrupt state. We use a simple spin lock for this
78 * proclist. Processes on this proclist are also on zombproc;
79 * we use the p_hash member to linkup to deadproc.
80 */
81 struct simplelock deadproc_slock;
82 struct proclist deadproc; /* dead, but not yet undead */
83
84 static void orphanpg(struct pgrp *);
85 #ifdef DEBUG
86 void pgrpdump(void);
87 #endif
88
89 /*
90 * Initialize global process hashing structures.
91 */
92 void
procinit()93 procinit()
94 {
95
96 LIST_INIT(&allproc);
97 LIST_INIT(&zombproc);
98
99 LIST_INIT(&deadproc);
100 simple_lock_init(&deadproc_slock);
101
102 pidhashtbl = hashinit(maxproc / 4, M_PROC, M_WAITOK, &pidhash);
103 pgrphashtbl = hashinit(maxproc / 4, M_PROC, M_WAITOK, &pgrphash);
104 uihashtbl = hashinit(maxproc / 16, M_PROC, M_WAITOK, &uihash);
105
106 pool_init(&proc_pool, sizeof(struct proc), 0, 0, 0, "procpl",
107 &pool_allocator_nointr);
108 pool_init(&rusage_pool, sizeof(struct rusage), 0, 0, 0, "zombiepl",
109 &pool_allocator_nointr);
110 pool_init(&ucred_pool, sizeof(struct ucred), 0, 0, 0, "ucredpl",
111 &pool_allocator_nointr);
112 pool_init(&pgrp_pool, sizeof(struct pgrp), 0, 0, 0, "pgrppl",
113 &pool_allocator_nointr);
114 pool_init(&session_pool, sizeof(struct session), 0, 0, 0, "sessionpl",
115 &pool_allocator_nointr);
116 pool_init(&pcred_pool, sizeof(struct pcred), 0, 0, 0, "pcredpl",
117 &pool_allocator_nointr);
118 }
119
120 /*
121 * Change the count associated with number of processes
122 * a given user is using.
123 */
124 struct uidinfo *
uid_find(uid_t uid)125 uid_find(uid_t uid)
126 {
127 struct uidinfo *uip;
128 struct uihashhead *uipp;
129
130 uipp = UIHASH(uid);
131 LIST_FOREACH(uip, uipp, ui_hash)
132 if (uip->ui_uid == uid)
133 break;
134 if (uip)
135 return (uip);
136 MALLOC(uip, struct uidinfo *, sizeof(*uip), M_PROC, M_WAITOK);
137 bzero(uip, sizeof(*uip));
138 LIST_INSERT_HEAD(uipp, uip, ui_hash);
139 uip->ui_uid = uid;
140
141 return (uip);
142 }
143
144 int
chgproccnt(uid_t uid,int diff)145 chgproccnt(uid_t uid, int diff)
146 {
147 struct uidinfo *uip;
148
149 uip = uid_find(uid);
150 uip->ui_proccnt += diff;
151 if (uip->ui_proccnt < 0)
152 panic("chgproccnt: procs < 0");
153 return (uip->ui_proccnt);
154 }
155
156 /*
157 * Is p an inferior of parent?
158 */
159 int
inferior(struct proc * p,struct proc * parent)160 inferior(struct proc *p, struct proc *parent)
161 {
162 for (; p != parent; p = p->p_pptr)
163 if (p->p_pid == 0 || p->p_pid == 1)
164 return (0);
165 return (1);
166 }
167
168 /*
169 * Locate a process by number
170 */
171 struct proc *
pfind(pid)172 pfind(pid)
173 register pid_t pid;
174 {
175 register struct proc *p;
176
177 for (p = PIDHASH(pid)->lh_first; p != 0; p = p->p_hash.le_next)
178 if (p->p_pid == pid)
179 return (p);
180 return (NULL);
181 }
182
183 /*
184 * Locate a process group by number
185 */
186 struct pgrp *
pgfind(pgid)187 pgfind(pgid)
188 register pid_t pgid;
189 {
190 register struct pgrp *pgrp;
191
192 for (pgrp = PGRPHASH(pgid)->lh_first; pgrp != 0; pgrp = pgrp->pg_hash.le_next)
193 if (pgrp->pg_id == pgid)
194 return (pgrp);
195 return (NULL);
196 }
197
198 /*
199 * Move p to a new or existing process group (and session)
200 */
201 int
enterpgrp(p,pgid,mksess)202 enterpgrp(p, pgid, mksess)
203 register struct proc *p;
204 pid_t pgid;
205 int mksess;
206 {
207 register struct pgrp *pgrp = pgfind(pgid);
208
209 #ifdef DIAGNOSTIC
210 if (pgrp != NULL && mksess) /* firewalls */
211 panic("enterpgrp: setsid into non-empty pgrp");
212 if (SESS_LEADER(p))
213 panic("enterpgrp: session leader attempted setpgrp");
214 #endif
215 if (pgrp == NULL) {
216 pid_t savepid = p->p_pid;
217 struct proc *np;
218 /*
219 * new process group
220 */
221 #ifdef DIAGNOSTIC
222 if (p->p_pid != pgid)
223 panic("enterpgrp: new pgrp and pid != pgid");
224 #endif
225 if ((np = pfind(savepid)) == NULL || np != p)
226 return (ESRCH);
227 pgrp = pool_get(&pgrp_pool, PR_WAITOK);
228 if (mksess) {
229 register struct session *sess;
230
231 /*
232 * new session
233 */
234 sess = pool_get(&session_pool, PR_WAITOK);
235 sess->s_leader = p;
236 sess->s_count = 1;
237 sess->s_ttyvp = NULL;
238 sess->s_ttyp = NULL;
239 bcopy(p->p_session->s_login, sess->s_login,
240 sizeof(sess->s_login));
241 p->p_flag &= ~P_CONTROLT;
242 pgrp->pg_session = sess;
243 #ifdef DIAGNOSTIC
244 if (p != curproc)
245 panic("enterpgrp: mksession and p != curproc");
246 #endif
247 } else {
248 pgrp->pg_session = p->p_session;
249 pgrp->pg_session->s_count++;
250 }
251 pgrp->pg_id = pgid;
252 LIST_INIT(&pgrp->pg_members);
253 LIST_INSERT_HEAD(PGRPHASH(pgid), pgrp, pg_hash);
254 pgrp->pg_jobc = 0;
255 } else if (pgrp == p->p_pgrp)
256 return (0);
257
258 /*
259 * Adjust eligibility of affected pgrps to participate in job control.
260 * Increment eligibility counts before decrementing, otherwise we
261 * could reach 0 spuriously during the first call.
262 */
263 fixjobc(p, pgrp, 1);
264 fixjobc(p, p->p_pgrp, 0);
265
266 LIST_REMOVE(p, p_pglist);
267 if (p->p_pgrp->pg_members.lh_first == 0)
268 pgdelete(p->p_pgrp);
269 p->p_pgrp = pgrp;
270 LIST_INSERT_HEAD(&pgrp->pg_members, p, p_pglist);
271 return (0);
272 }
273
274 /*
275 * remove process from process group
276 */
277 int
leavepgrp(p)278 leavepgrp(p)
279 register struct proc *p;
280 {
281
282 LIST_REMOVE(p, p_pglist);
283 if (p->p_pgrp->pg_members.lh_first == 0)
284 pgdelete(p->p_pgrp);
285 p->p_pgrp = 0;
286 return (0);
287 }
288
289 /*
290 * delete a process group
291 */
292 void
pgdelete(pgrp)293 pgdelete(pgrp)
294 register struct pgrp *pgrp;
295 {
296
297 if (pgrp->pg_session->s_ttyp != NULL &&
298 pgrp->pg_session->s_ttyp->t_pgrp == pgrp)
299 pgrp->pg_session->s_ttyp->t_pgrp = NULL;
300 LIST_REMOVE(pgrp, pg_hash);
301 SESSRELE(pgrp->pg_session);
302 pool_put(&pgrp_pool, pgrp);
303 }
304
305 /*
306 * Adjust pgrp jobc counters when specified process changes process group.
307 * We count the number of processes in each process group that "qualify"
308 * the group for terminal job control (those with a parent in a different
309 * process group of the same session). If that count reaches zero, the
310 * process group becomes orphaned. Check both the specified process'
311 * process group and that of its children.
312 * entering == 0 => p is leaving specified group.
313 * entering == 1 => p is entering specified group.
314 */
315 void
fixjobc(p,pgrp,entering)316 fixjobc(p, pgrp, entering)
317 register struct proc *p;
318 register struct pgrp *pgrp;
319 int entering;
320 {
321 register struct pgrp *hispgrp;
322 register struct session *mysession = pgrp->pg_session;
323
324 /*
325 * Check p's parent to see whether p qualifies its own process
326 * group; if so, adjust count for p's process group.
327 */
328 if ((hispgrp = p->p_pptr->p_pgrp) != pgrp &&
329 hispgrp->pg_session == mysession) {
330 if (entering)
331 pgrp->pg_jobc++;
332 else if (--pgrp->pg_jobc == 0)
333 orphanpg(pgrp);
334 }
335
336 /*
337 * Check this process' children to see whether they qualify
338 * their process groups; if so, adjust counts for children's
339 * process groups.
340 */
341 for (p = p->p_children.lh_first; p != 0; p = p->p_sibling.le_next)
342 if ((hispgrp = p->p_pgrp) != pgrp &&
343 hispgrp->pg_session == mysession &&
344 P_ZOMBIE(p) == 0) {
345 if (entering)
346 hispgrp->pg_jobc++;
347 else if (--hispgrp->pg_jobc == 0)
348 orphanpg(hispgrp);
349 }
350 }
351
352 /*
353 * A process group has become orphaned;
354 * if there are any stopped processes in the group,
355 * hang-up all process in that group.
356 */
357 static void
orphanpg(pg)358 orphanpg(pg)
359 struct pgrp *pg;
360 {
361 register struct proc *p;
362
363 for (p = pg->pg_members.lh_first; p != 0; p = p->p_pglist.le_next) {
364 if (p->p_stat == SSTOP) {
365 for (p = pg->pg_members.lh_first; p != 0;
366 p = p->p_pglist.le_next) {
367 psignal(p, SIGHUP);
368 psignal(p, SIGCONT);
369 }
370 return;
371 }
372 }
373 }
374
375 void
proc_printit(struct proc * p,const char * modif,int (* pr)(const char *,...))376 proc_printit(struct proc *p, const char *modif, int (*pr)(const char *, ...))
377 {
378 static const char *const pstat[] = {
379 "idle", "run", "sleep", "stop", "zombie", "dead"
380 };
381 char pstbuf[5];
382 const char *pst = pstbuf;
383
384 if (p->p_stat < 1 || p->p_stat > sizeof(pstat) / sizeof(pstat[0]))
385 snprintf(pstbuf, sizeof(pstbuf), "%d", p->p_stat);
386 else
387 pst = pstat[(int)p->p_stat - 1];
388
389 (*pr)("PROC (%s) pid=%d stat=%s flags=%b\n",
390 p->p_comm, p->p_pid, pst, p->p_flag, P_BITS);
391 (*pr)(" pri=%u, usrpri=%u, nice=%d\n",
392 p->p_priority, p->p_usrpri, p->p_nice);
393 (*pr)(" forw=%p, back=%p, list=%p,%p\n",
394 p->p_forw, p->p_back, p->p_list.le_next, p->p_list.le_prev);
395 (*pr)(" user=%p, vmspace=%p\n",
396 p->p_addr, p->p_vmspace);
397 (*pr)(" estcpu=%u, cpticks=%d, pctcpu=%u.%u%, swtime=%u\n",
398 p->p_estcpu, p->p_cpticks, p->p_pctcpu / 100, p->p_pctcpu % 100,
399 p->p_swtime);
400 (*pr)(" user=%llu, sys=%llu, intr=%llu\n",
401 p->p_uticks, p->p_sticks, p->p_iticks);
402 }
403
404 #ifdef DEBUG
405 void
pgrpdump()406 pgrpdump()
407 {
408 register struct pgrp *pgrp;
409 register struct proc *p;
410 register int i;
411
412 for (i = 0; i <= pgrphash; i++) {
413 if ((pgrp = pgrphashtbl[i].lh_first) != NULL) {
414 printf("\tindx %d\n", i);
415 for (; pgrp != 0; pgrp = pgrp->pg_hash.le_next) {
416 printf("\tpgrp %p, pgid %d, sess %p, sesscnt %d, mem %p\n",
417 pgrp, pgrp->pg_id, pgrp->pg_session,
418 pgrp->pg_session->s_count,
419 pgrp->pg_members.lh_first);
420 for (p = pgrp->pg_members.lh_first; p != 0;
421 p = p->p_pglist.le_next) {
422 printf("\t\tpid %d addr %p pgrp %p\n",
423 p->p_pid, p, p->p_pgrp);
424 }
425 }
426 }
427 }
428 }
429 #endif /* DEBUG */
430