X-Git-Url: https://git.subgeniuskitty.com/unix-history/.git/blobdiff_plain/773142c4b292ffdedefa4ea558a6caa44b82a395..01932c99d1800e02c98500a66b1c9d62d0f820c8:/usr/src/sys/kern/kern_exit.c

diff --git a/usr/src/sys/kern/kern_exit.c b/usr/src/sys/kern/kern_exit.c
index 53bcd2304f..a86e27b0b6 100644
--- a/usr/src/sys/kern/kern_exit.c
+++ b/usr/src/sys/kern/kern_exit.c
@@ -1,125 +1,126 @@
 /*
- * Copyright (c) 1982, 1986, 1989 Regents of the University of California.
+ * Copyright (c) 1982, 1986, 1989, 1991 Regents of the University of California.
  * All rights reserved.
  *
- * Redistribution and use in source and binary forms are permitted
- * provided that the above copyright notice and this paragraph are
- * duplicated in all such forms and that any documentation,
- * advertising materials, and other materials related to such
- * distribution and use acknowledge that the software was developed
- * by the University of California, Berkeley.  The name of the
- * University may not be used to endorse or promote products derived
- * from this software without specific prior written permission.
- * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR
- * IMPLIED WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED
- * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
+ * %sccs.include.redist.c%
  *
- *	@(#)kern_exit.c	7.21 (Berkeley) %G%
+ *	@(#)kern_exit.c	7.43 (Berkeley) %G%
  */
 
 #include "param.h"
 #include "systm.h"
 #include "map.h"
-#include "user.h"
-#include "kernel.h"
+#include "ioctl.h"
 #include "proc.h"
+#include "tty.h"
+#include "time.h"
+#include "resource.h"
+#include "kernel.h"
 #include "buf.h"
 #include "wait.h"
-#include "vm.h"
 #include "file.h"
 #include "vnode.h"
-#include "ioctl.h"
-#include "tty.h"
 #include "syslog.h"
 #include "malloc.h"
+#include "resourcevar.h"
 
-#include "machine/reg.h"
+#include "machine/cpu.h"
 #ifdef COMPAT_43
+#include "machine/reg.h"
 #include "machine/psl.h"
 #endif
 
+#include "vm/vm.h"
+#include "vm/vm_kern.h"
+
 /*
  * Exit system call: pass back caller's arg
  */
-rexit()
-{
-	struct a {
+/* ARGSUSED */
+rexit(p, uap, retval)
+	struct proc *p;
+	struct args {
 		int	rval;
 	} *uap;
+	int *retval;
+{
 
-	uap = (struct a *)u.u_ap;
-	exit(W_EXITCODE(uap->rval, 0));
+	exit(p, W_EXITCODE(uap->rval, 0));
+	/* NOTREACHED */
 }
 
 /*
- * Release resources.
- * Save u. area for parent to look at.
- * Enter zombie state.
- * Wake up parent and init processes,
- * and dispose of children.
+ * Exit: deallocate address space and other resources,
+ * change proc state to zombie, and unlink proc from allproc
+ * and parent's lists.  Save exit status and rusage for wait().
+ * Check for child processes and orphan them.
  */
-exit(rv)
+exit(p, rv)
+	register struct proc *p;
 	int rv;
 {
-	register int i;
-	register struct proc *p, *q, *nq;
+	register struct proc *q, *nq;
 	register struct proc **pp;
+	register struct vmspace *vm;
+	int s;
 
 #ifdef PGINPROF
 	vmsizmon();
 #endif
-	p = u.u_procp;
 	MALLOC(p->p_ru, struct rusage *, sizeof(struct rusage),
 		M_ZOMBIE, M_WAITOK);
-	p->p_flag &= ~(STRC|SULOCK);
+	/*
+	 * If parent is waiting for us to exit or exec,
+	 * SPPWAIT is set; we will wakeup the parent below.
+	 */
+	p->p_flag &= ~(STRC|SPPWAIT);
 	p->p_flag |= SWEXIT;
 	p->p_sigignore = ~0;
 	p->p_sig = 0;
-	p->p_cpticks = 0;
-	p->p_pctcpu = 0;
-	for (i = 0; i < NSIG; i++)
-		u.u_signal[i] = SIG_IGN;
 	untimeout(realitexpire, (caddr_t)p);
+
 	/*
-	 * Release virtual memory.  If we resulted from
-	 * a vfork(), instead give the resources back to
-	 * the parent.
+	 * Close open files and release open-file table.
+	 * This may block!
 	 */
-	if ((p->p_flag & SVFORK) == 0) {
-#ifdef MAPMEM
-		if (u.u_mmap)
-			mmexit();
+	fdfree(p);
+
+	/* The next two chunks should probably be moved to vmspace_exit. */
+	vm = p->p_vmspace;
+#ifdef SYSVSHM
+	if (vm->vm_shm)
+		shmexit(p);
 #endif
-		vrelvm();
-	} else {
-		p->p_flag &= ~SVFORK;
-		wakeup((caddr_t)p);
-		while ((p->p_flag & SVFDONE) == 0)
-			sleep((caddr_t)p, PZERO - 1);
-		p->p_flag &= ~SVFDONE;
-	}
-	for (i = 0; i <= u.u_lastfile; i++) {
-		struct file *f;
+	/*
+	 * Release user portion of address space.
+	 * This releases references to vnodes,
+	 * which could cause I/O if the file has been unlinked.
+	 * Need to do this early enough that we can still sleep.
+	 * Can't free the entire vmspace as the kernel stack
+	 * may be mapped within that space also.
+	 */
+	if (vm->vm_refcnt == 1)
+		(void) vm_map_remove(&vm->vm_map, VM_MIN_ADDRESS,
+		    VM_MAXUSER_ADDRESS);
 
-		f = u.u_ofile[i];
-		if (f) {
-			u.u_ofile[i] = NULL;
-			u.u_pofile[i] = 0;
-			(void) closef(f);
-		}
-	}
+	if (p->p_pid == 1)
+		panic("init died");
 	if (SESS_LEADER(p)) {
 		register struct session *sp = p->p_session;
 
 		if (sp->s_ttyvp) {
 			/*
 			 * Controlling process.
-			 * Signal foreground pgrp and revoke access
-			 * to controlling terminal.
+			 * Signal foreground pgrp,
+			 * drain controlling terminal
+			 * and revoke access to controlling terminal.
 			 */
-			if (sp->s_ttyp->t_pgrp)
-				pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1);
-			vgoneall(sp->s_ttyvp);
+			if (sp->s_ttyp->t_session == sp) {
+				if (sp->s_ttyp->t_pgrp)
+					pgsignal(sp->s_ttyp->t_pgrp, SIGHUP, 1);
+				(void) ttywait(sp->s_ttyp);
+				vgoneall(sp->s_ttyvp);
+			}
 			vrele(sp->s_ttyvp);
 			sp->s_ttyvp = NULL;
 			/*
@@ -128,41 +129,31 @@ exit(rv)
 			 * (for logging and informational purposes)
 			 */
 		}
-		sp->s_leader = 0;
+		sp->s_leader = NULL;
 	}
-	VOP_LOCK(u.u_cdir);
-	vput(u.u_cdir);
-	if (u.u_rdir) {
-		VOP_LOCK(u.u_rdir);
-		vput(u.u_rdir);
-	}
-	u.u_rlimit[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
-	acct();
-	crfree(u.u_cred);
+	fixjobc(p, p->p_pgrp, 0);
+	p->p_rlimit[RLIMIT_FSIZE].rlim_cur = RLIM_INFINITY;
+	(void) acct(p);
 #ifdef KTRACE
 	/* 
 	 * release trace file
 	 */
+	p->p_traceflag = 0;	/* don't trace the vrele() */
 	if (p->p_tracep)
 		vrele(p->p_tracep);
 #endif
 	/*
-	 * Freeing the user structure and kernel stack
-	 * for the current process: have to run a bit longer
-	 * using the pages which are about to be freed...
-	 * vrelu will block memory allocation by raising ipl.
+	 * Remove proc from allproc queue and pidhash chain.
+	 * Place onto zombproc.  Unlink from parent's child list.
 	 */
-	vrelu(u.u_procp, 0);
-	vrelpt(u.u_procp);
-	if (*p->p_prev = p->p_nxt)		/* off allproc queue */
+	if (*p->p_prev = p->p_nxt)
 		p->p_nxt->p_prev = p->p_prev;
-	if (p->p_nxt = zombproc)		/* onto zombproc */
+	if (p->p_nxt = zombproc)
 		p->p_nxt->p_prev = &p->p_nxt;
 	p->p_prev = &zombproc;
 	zombproc = p;
-	multprog--;
 	p->p_stat = SZOMB;
-	noproc = 1;
+
 	for (pp = &pidhash[PIDHASH(p->p_pid)]; *pp; pp = &(*pp)->p_hash)
 		if (*pp == p) {
 			*pp = p->p_hash;
@@ -170,36 +161,20 @@ exit(rv)
 		}
 	panic("exit");
 done:
-	if (p->p_pid == 1) {
-		if (p->p_dsize == 0) {
-			printf("Can't exec init (errno %d)\n", WEXITSTATUS(rv));
-			for (;;)
-				;
-		} else
-			panic("init died");
-	}
-	p->p_xstat = rv;
-	*p->p_ru = u.u_ru;
-	i = splclock();
-	p->p_ru->ru_stime = p->p_stime;
-	p->p_ru->ru_utime = p->p_utime;
-	splx(i);
-	ruadd(p->p_ru, &u.u_cru);
+
 	if (p->p_cptr)		/* only need this if any child is S_ZOMB */
-		wakeup((caddr_t)&proc[1]);
-	fixjobc(p, 0);
+		wakeup((caddr_t) initproc);
 	for (q = p->p_cptr; q != NULL; q = nq) {
 		nq = q->p_osptr;
 		if (nq != NULL)
 			nq->p_ysptr = NULL;
-		if (proc[1].p_cptr)
-			proc[1].p_cptr->p_ysptr = q;
-		q->p_osptr = proc[1].p_cptr;
+		if (initproc->p_cptr)
+			initproc->p_cptr->p_ysptr = q;
+		q->p_osptr = initproc->p_cptr;
 		q->p_ysptr = NULL;
-		proc[1].p_cptr = q;
+		initproc->p_cptr = q;
 
-		q->p_pptr = &proc[1];
-		q->p_ppid = 1;
+		q->p_pptr = initproc;
 		/*
 		 * Traced processes are killed
 		 * since their existence means someone is screwing up.
@@ -210,67 +185,111 @@ done:
 		}
 	}
 	p->p_cptr = NULL;
+
+	/*
+	 * Save exit status and final rusage info,
+	 * adding in child rusage info and self times.
+	 */
+	p->p_xstat = rv;
+	*p->p_ru = p->p_stats->p_ru;
+	p->p_ru->ru_stime = p->p_stime;
+	p->p_ru->ru_utime = p->p_utime;
+	ruadd(p->p_ru, &p->p_stats->p_cru);
+
+	/*
+	 * Notify parent that we're gone.
+	 */
 	psignal(p->p_pptr, SIGCHLD);
 	wakeup((caddr_t)p->p_pptr);
 #if defined(tahoe)
-	dkeyrelease(p->p_dkey), p->p_dkey = 0;
-	ckeyrelease(p->p_ckey), p->p_ckey = 0;
-	u.u_pcb.pcb_savacc.faddr = (float *)NULL;
+	/* move this to cpu_exit */
+	p->p_addr->u_pcb.pcb_savacc.faddr = (float *)NULL;
 #endif
-	swtch();
+	/*
+	 * Clear curproc after we've done all operations
+	 * that could block, and before tearing down the rest
+	 * of the process state that might be used from clock, etc.
+	 * Also, can't clear curproc while we're still runnable,
+	 * as we're not on a run queue (we are current, just not
+	 * a proper proc any longer!).
+	 *
+	 * Other substructures are freed from wait().
+	 */
+	curproc = NULL;
+	if (--p->p_limit->p_refcnt == 0)
+		FREE(p->p_limit, M_SUBPROC);
+
+	/*
+	 * Finally, call machine-dependent code to release the remaining
+	 * resources including address space, the kernel stack and pcb.
+	 * The address space is released by "vmspace_free(p->p_vmspace)";
+	 * This is machine-dependent, as we may have to change stacks
+	 * or ensure that the current one isn't reallocated before we
+	 * finish.  cpu_exit will end with a call to swtch(), finishing
+	 * our execution (pun intended).
+	 */
+	cpu_exit(p);
+	/* NOTREACHED */
 }
 
 #ifdef COMPAT_43
-owait()
-{
-	register struct a {
+owait(p, uap, retval)
+	struct proc *p;
+	register struct args {
 		int	pid;
 		int	*status;
 		int	options;
 		struct	rusage *rusage;
 		int	compat;
-	} *uap = (struct a *)u.u_ap;
+	} *uap;
+	int *retval;
+{
 
-	if ((u.u_ar0[PS] & PSL_ALLCC) != PSL_ALLCC) {
+#ifdef PSL_ALLCC
+	if ((p->p_md.md_regs[PS] & PSL_ALLCC) != PSL_ALLCC) {
 		uap->options = 0;
 		uap->rusage = 0;
 	} else {
-		uap->options = u.u_ar0[R0];
-		uap->rusage = (struct rusage *)u.u_ar0[R1];
+		uap->options = p->p_md.md_regs[R0];
+		uap->rusage = (struct rusage *)p->p_md.md_regs[R1];
 	}
+#else
+	uap->options = 0;
+	uap->rusage = 0;
+#endif
 	uap->pid = WAIT_ANY;
 	uap->status = 0;
 	uap->compat = 1;
-	u.u_error = wait1();
+	return (wait1(p, uap, retval));
 }
 
-wait4()
-{
-	register struct a {
+wait4(p, uap, retval)
+	struct proc *p;
+	struct args {
 		int	pid;
 		int	*status;
 		int	options;
 		struct	rusage *rusage;
 		int	compat;
-	} *uap = (struct a *)u.u_ap;
+	} *uap;
+	int *retval;
+{
 
 	uap->compat = 0;
-	u.u_error = wait1();
+	return (wait1(p, uap, retval));
 }
 #else
 #define	wait1	wait4
 #endif
 
 /*
- * Wait system call.
- * Search for a terminated (zombie) child,
- * finally lay it to rest, and collect its status.
- * Look also for stopped (traced) children,
- * and pass back status from them.
+ * Wait: check child processes to see if any have exited,
+ * stopped under trace, or (optionally) stopped by a signal.
+ * Pass back status and deallocate exited child's proc structure.
  */
-wait1()
-{
-	register struct a {
+wait1(q, uap, retval)
+	register struct proc *q;
+	register struct args {
 		int	pid;
 		int	*status;
 		int	options;
@@ -278,12 +297,13 @@ wait1()
 #ifdef COMPAT_43
 		int compat;
 #endif
-	} *uap = (struct a *)u.u_ap;
-	register f;
-	register struct proc *p, *q;
+	} *uap;
+	int retval[];
+{
+	register int nfound;
+	register struct proc *p;
 	int status, error;
 
-	q = u.u_procp;
 	if (uap->pid == 0)
 		uap->pid = -q->p_pgid;
 #ifdef notyet
@@ -291,17 +311,17 @@ wait1()
 		return (EINVAL);
 #endif
 loop:
-	f = 0;
+	nfound = 0;
 	for (p = q->p_cptr; p; p = p->p_osptr) {
 		if (uap->pid != WAIT_ANY &&
 		    p->p_pid != uap->pid && p->p_pgid != -uap->pid)
 			continue;
-		f++;
+		nfound++;
 		if (p->p_stat == SZOMB) {
-			u.u_r.r_val1 = p->p_pid;
+			retval[0] = p->p_pid;
 #ifdef COMPAT_43
 			if (uap->compat)
-				u.u_r.r_val2 = p->p_xstat;
+				retval[1] = p->p_xstat;
 			else
 #endif
 			if (uap->status) {
@@ -313,64 +333,64 @@ loop:
 			if (uap->rusage && (error = copyout((caddr_t)p->p_ru,
 			    (caddr_t)uap->rusage, sizeof (struct rusage))))
 				return (error);
-			pgrm(p);			/* off pgrp */
 			p->p_xstat = 0;
-			ruadd(&u.u_cru, p->p_ru);
+			ruadd(&q->p_stats->p_cru, p->p_ru);
 			FREE(p->p_ru, M_ZOMBIE);
-			p->p_ru = 0;
-			p->p_stat = NULL;
-			p->p_pid = 0;
-			p->p_ppid = 0;
+			if (--p->p_cred->p_refcnt == 0) {
+				crfree(p->p_cred->pc_ucred);
+				FREE(p->p_cred, M_SUBPROC);
+			}
+
+			/*
+			 * Finally finished with old proc entry.
+			 * Unlink it from its process group and free it.
+			 */
+			leavepgrp(p);
 			if (*p->p_prev = p->p_nxt)	/* off zombproc */
 				p->p_nxt->p_prev = p->p_prev;
-			p->p_nxt = freeproc;		/* onto freeproc */
-			freeproc = p;
 			if (q = p->p_ysptr)
 				q->p_osptr = p->p_osptr;
 			if (q = p->p_osptr)
 				q->p_ysptr = p->p_ysptr;
 			if ((q = p->p_pptr)->p_cptr == p)
 				q->p_cptr = p->p_osptr;
-			p->p_pptr = 0;
-			p->p_ysptr = 0;
-			p->p_osptr = 0;
-			p->p_cptr = 0;
-			p->p_sig = 0;
-			p->p_sigcatch = 0;
-			p->p_sigignore = 0;
-			p->p_sigmask = 0;
-			/*p->p_pgrp = 0;*/
-			p->p_flag = 0;
-			p->p_wchan = 0;
-			p->p_cursig = 0;
+
+			/*
+			 * Give machine-dependent layer a chance
+			 * to free anything that cpu_exit couldn't
+			 * release while still running in process context.
+			 */
+			cpu_wait(p);
+			FREE(p, M_PROC);
+			nprocs--;
 			return (0);
 		}
 		if (p->p_stat == SSTOP && (p->p_flag & SWTED) == 0 &&
 		    (p->p_flag & STRC || uap->options & WUNTRACED)) {
 			p->p_flag |= SWTED;
-			u.u_r.r_val1 = p->p_pid;
+			retval[0] = p->p_pid;
 #ifdef COMPAT_43
 			if (uap->compat) {
-				u.u_r.r_val2 = W_STOPCODE(p->p_cursig);
+				retval[1] = W_STOPCODE(p->p_xstat);
 				error = 0;
 			} else
 #endif
 			if (uap->status) {
-				status = W_STOPCODE(p->p_cursig);
+				status = W_STOPCODE(p->p_xstat);
 				error = copyout((caddr_t)&status,
-				    (caddr_t)uap->status, sizeof(status));
+					(caddr_t)uap->status, sizeof(status));
 			} else
 				error = 0;
 			return (error);
 		}
 	}
-	if (f == 0)
+	if (nfound == 0)
 		return (ECHILD);
 	if (uap->options & WNOHANG) {
-		u.u_r.r_val1 = 0;
+		retval[0] = 0;
 		return (0);
 	}
-	if (error = tsleep((caddr_t)u.u_procp, PWAIT | PCATCH, "wait", 0))
+	if (error = tsleep((caddr_t)q, PWAIT | PCATCH, "wait", 0))
 		return (error);
 	goto loop;
 }