X-Git-Url: https://git.saurik.com/apple/xnu.git/blobdiff_plain/89b3af67bb32e691275bf6fa803d1834b2284115..bd504ef0e0b883cdd7917b73b3574eb9ce669905:/bsd/kern/kern_proc.c

diff --git a/bsd/kern/kern_proc.c b/bsd/kern/kern_proc.c
index de3c6bcf6..6d696b424 100644
--- a/bsd/kern/kern_proc.c
+++ b/bsd/kern/kern_proc.c
@@ -1,5 +1,5 @@
 /*
- * Copyright (c) 2000-2002 Apple Computer, Inc. All rights reserved.
+ * Copyright (c) 2000-2007 Apple Inc. All rights reserved.
  *
  * @APPLE_OSREFERENCE_LICENSE_HEADER_START@
  * 
@@ -60,6 +60,12 @@
  *
  *	@(#)kern_proc.c	8.4 (Berkeley) 1/4/94
  */
+/*
+ * NOTICE: This file was modified by SPARTA, Inc. in 2005 to introduce
+ * support for mandatory and extensible security protections.  This notice
+ * is included in support of clause 2.2 (b) of the Apple Public License,
+ * Version 2.0.
+ */
 /* HISTORY
  *  04-Aug-97  Umesh Vaishampayan (umeshv@apple.com)
  *	Added current_proc_EXTERNAL() function for the use of kernel
@@ -77,15 +83,33 @@
 #include <sys/acct.h>
 #include <sys/wait.h>
 #include <sys/file_internal.h>
-#include <ufs/ufs/quota.h>
 #include <sys/uio.h>
 #include <sys/malloc.h>
+#include <sys/lock.h>
 #include <sys/mbuf.h>
 #include <sys/ioctl.h>
 #include <sys/tty.h>
 #include <sys/signalvar.h>
 #include <sys/syslog.h>
+#include <sys/sysctl.h>
+#include <sys/sysproto.h>
+#include <sys/kauth.h>
+#include <sys/codesign.h>
 #include <sys/kernel_types.h>
+#include <sys/ubc.h>
+#include <kern/kalloc.h>
+#include <kern/task.h>
+#include <kern/assert.h>
+#include <vm/vm_protos.h>
+#include <vm/vm_map.h>		/* vm_map_switch_protect() */
+#include <mach/task.h>
+#include <mach/message.h>
+
+#if CONFIG_MACF
+#include <security/mac_framework.h>
+#endif
+
+#include <libkern/crypto/sha1.h>
 
 /*
  * Structure associated with user cacheing.
@@ -106,192 +130,465 @@ struct pidhashhead *pidhashtbl;
 u_long pidhash;
 struct pgrphashhead *pgrphashtbl;
 u_long pgrphash;
+struct sesshashhead *sesshashtbl;
+u_long sesshash;
+
 struct proclist allproc;
 struct proclist zombproc;
 extern struct tty cons;
 
+#if CONFIG_LCTX
+/*
+ * Login Context
+ */
+static pid_t	lastlcid = 1;
+static int	alllctx_cnt;
+
+#define	LCID_MAX	8192	/* Does this really need to be large? */
+static int	maxlcid = LCID_MAX;
+
+LIST_HEAD(lctxlist, lctx);
+static struct lctxlist alllctx;
+
+lck_mtx_t alllctx_lock;
+lck_grp_t * lctx_lck_grp;
+lck_grp_attr_t * lctx_lck_grp_attr;
+lck_attr_t * lctx_lck_attr;
+
+static	void	lctxinit(void);
+#endif
+
+int cs_debug;	/* declared further down in this file */
+
+#if DEBUG
+#define __PROC_INTERNAL_DEBUG 1
+#endif
 /* Name to give to core files */
 __private_extern__ char corefilename[MAXPATHLEN+1] = {"/cores/core.%P"};
 
 static void orphanpg(struct pgrp *pg);
+void 	proc_name_kdp(task_t t, char * buf, int size);
+char	*proc_name_address(void *p);
+
+static void  pgrp_add(struct pgrp * pgrp, proc_t parent, proc_t child);
+static void pgrp_remove(proc_t p);
+static void pgrp_replace(proc_t p, struct pgrp *pgrp);
+static void pgdelete_dropref(struct pgrp *pgrp);
+extern void pg_rele_dropref(struct pgrp * pgrp);
+static int csops_internal(pid_t pid, int ops, user_addr_t uaddr, user_size_t usersize, user_addr_t uaddittoken);
+
+struct fixjob_iterargs {
+	struct pgrp * pg;
+	struct session * mysession;
+	int entering;
+};
+
+int fixjob_callback(proc_t, void *);
 
 /*
  * Initialize global process hashing structures.
  */
 void
-procinit()
+procinit(void)
 {
-
 	LIST_INIT(&allproc);
 	LIST_INIT(&zombproc);
 	pidhashtbl = hashinit(maxproc / 4, M_PROC, &pidhash);
 	pgrphashtbl = hashinit(maxproc / 4, M_PROC, &pgrphash);
+	sesshashtbl = hashinit(maxproc / 4, M_PROC, &sesshash);
 	uihashtbl = hashinit(maxproc / 16, M_PROC, &uihash);
+#if CONFIG_LCTX
+	lctxinit();
+#endif
 }
 
 /*
  * Change the count associated with number of processes
- * a given user is using.
+ * a given user is using. This routine protects the uihash
+ * with the list lock
  */
 int
-chgproccnt(uid, diff)
-	uid_t	uid;
-	int	diff;
+chgproccnt(uid_t uid, int diff)
 {
-	register struct uidinfo *uip;
-	register struct uihashhead *uipp;
+	struct uidinfo *uip;
+	struct uidinfo *newuip = NULL;
+	struct uihashhead *uipp;
+	int retval;
 
+again:
+	proc_list_lock();
 	uipp = UIHASH(uid);
 	for (uip = uipp->lh_first; uip != 0; uip = uip->ui_hash.le_next)
 		if (uip->ui_uid == uid)
 			break;
 	if (uip) {
 		uip->ui_proccnt += diff;
-		if (uip->ui_proccnt > 0)
-			return (uip->ui_proccnt);
+		if (uip->ui_proccnt > 0) {
+			retval = uip->ui_proccnt;
+			proc_list_unlock();
+			goto out;
+		}
 		if (uip->ui_proccnt < 0)
 			panic("chgproccnt: procs < 0");
 		LIST_REMOVE(uip, ui_hash);
-		FREE_ZONE(uip, sizeof *uip, M_PROC);
-		return (0);
+		retval = 0;
+		proc_list_unlock();
+		FREE_ZONE(uip, sizeof(*uip), M_PROC);
+		goto out;
 	}
 	if (diff <= 0) {
-		if (diff == 0)
-			return(0);
+		if (diff == 0) {
+			retval = 0;
+			proc_list_unlock();
+			goto out;
+		}
 		panic("chgproccnt: lost user");
 	}
-	MALLOC_ZONE(uip, struct uidinfo *, sizeof(*uip), M_PROC, M_WAITOK);
-	if (uip == NULL)
+	if (newuip != NULL) {
+		uip = newuip;
+		newuip = NULL;
+		LIST_INSERT_HEAD(uipp, uip, ui_hash);
+		uip->ui_uid = uid;
+		uip->ui_proccnt = diff;
+		retval = diff;
+		proc_list_unlock();
+		goto out;
+	}
+	proc_list_unlock();
+	MALLOC_ZONE(newuip, struct uidinfo *, sizeof(*uip), M_PROC, M_WAITOK);
+	if (newuip == NULL)
 		panic("chgproccnt: M_PROC zone depleted");
-	LIST_INSERT_HEAD(uipp, uip, ui_hash);
-	uip->ui_uid = uid;
-	uip->ui_proccnt = diff;
-	return (diff);
+	goto again;
+out:
+	if (newuip != NULL) 
+		FREE_ZONE(newuip, sizeof(*uip), M_PROC);
+	return(retval);
 }
 
 /*
  * Is p an inferior of the current process?
  */
 int
-inferior(p)
-	register struct proc *p;
+inferior(proc_t p)
 {
+	int retval = 0;
 
+	proc_list_lock();
 	for (; p != current_proc(); p = p->p_pptr)
-		if (p->p_pid == 0)
-			return (0);
-	return (1);
+		if (p->p_pid == 0) 
+			goto out;
+	retval = 1;
+out:
+	proc_list_unlock();
+	return(retval);
 }
+
 /*
  * Is p an inferior of t ?
  */
 int
-isinferior(struct proc *p, struct proc *t)
+isinferior(proc_t p, proc_t t)
 {
+	int retval = 0;
+	int nchecked = 0;
+	proc_t start = p;
 
 	/* if p==t they are not inferior */
 	if (p == t)
 		return(0);
-	for (; p != t; p = p->p_pptr)
-		if (p->p_pid == 0)
-			return (0);
-	return (1);
+
+	proc_list_lock();
+	for (; p != t; p = p->p_pptr) {
+		nchecked++;
+
+		/* Detect here if we're in a cycle */
+		if ((p->p_pid == 0) || (p->p_pptr == start) || (nchecked >= nprocs))
+			goto out;
+	}
+	retval = 1;
+out:
+	proc_list_unlock();
+	return(retval);
 }
 
 int
 proc_isinferior(int pid1, int pid2)
 {
-	proc_t p;
-	proc_t t;
+	proc_t p = PROC_NULL;
+	proc_t t = PROC_NULL;
+	int retval = 0;
+	
+	if (((p = proc_find(pid1)) != (proc_t)0 ) && ((t = proc_find(pid2)) != (proc_t)0))
+		retval = isinferior(p, t);
 
-	if (((p = pfind(pid1)) != (struct proc *)0 ) && ((t = pfind(pid2)) != (struct proc *)0))
-		return (isinferior(p, t));
-	return(0);
+	if (p != PROC_NULL)
+		proc_rele(p);
+	if (t != PROC_NULL)
+		proc_rele(t);
+
+	return(retval);
 }
 
 proc_t
 proc_find(int pid)
 {
-	return(pfind(pid));
+	return(proc_findinternal(pid, 0));
 }
 
-int 
-proc_rele(__unused proc_t p)
+proc_t
+proc_findinternal(int pid, int locked)
 {
-	return(0);
+	proc_t p = PROC_NULL;
+
+	if (locked == 0) {
+		proc_list_lock();
+	}
+
+	p = pfind_locked(pid);
+	if ((p == PROC_NULL) || (p != proc_ref_locked(p)))
+		p = PROC_NULL;
+
+	if (locked == 0) {
+		proc_list_unlock();
+	}
+
+	return(p);
 }
 
 proc_t
-proc_self()
+proc_findthread(thread_t thread)
 {
-	return(current_proc());
+	proc_t p = PROC_NULL;
+	struct uthread *uth;
+
+	proc_list_lock();
+	uth = get_bsdthread_info(thread);
+	if (uth && (uth->uu_flag & UT_VFORK))
+		p = uth->uu_proc;
+	else
+		p = (proc_t)(get_bsdthreadtask_info(thread));
+	p = proc_ref_locked(p);
+	proc_list_unlock();
+	return(p);
+}
+
+int 
+proc_rele(proc_t p)
+{
+	proc_list_lock();
+	proc_rele_locked(p);
+	proc_list_unlock();
+
+	return(0);
 }
 
 proc_t
-proc_findref(int pid)
+proc_self(void)
 {
-	boolean_t funnel_state;
-	proc_t p;
+	struct proc * p;
 
-	funnel_state = thread_funnel_set(kernel_flock,TRUE);
-	p = pfind(pid);
-	
-	if (p != proc_refinternal(p, 1))
+	p = current_proc();
+
+	proc_list_lock();
+	if (p != proc_ref_locked(p))
 		p = PROC_NULL;
-		
-	thread_funnel_set(kernel_flock, funnel_state);
+	proc_list_unlock();
 	return(p);
 }
 
-void
-proc_dropref(proc_t p)
+
+proc_t
+proc_ref_locked(proc_t p)
 {
+	proc_t p1 = p;
+	
+	/* if process still in creation return failure */
+	if ((p == PROC_NULL) || ((p->p_listflag & P_LIST_INCREATE) != 0))
+			return (PROC_NULL);
+	/* do not return process marked for termination */
+	if ((p->p_stat != SZOMB) && ((p->p_listflag & P_LIST_EXITED) == 0) && ((p->p_listflag & (P_LIST_DRAINWAIT | P_LIST_DRAIN | P_LIST_DEAD)) == 0))
+		p->p_refcount++;
+	else 
+		p1 = PROC_NULL;
 
-	proc_dropinternal(p, 0);
+	return(p1);
 }
 
+void
+proc_rele_locked(proc_t p)
+{
+
+	if (p->p_refcount > 0) {
+		p->p_refcount--;
+		if ((p->p_refcount == 0) && ((p->p_listflag & P_LIST_DRAINWAIT) == P_LIST_DRAINWAIT)) {
+			p->p_listflag &= ~P_LIST_DRAINWAIT;
+			wakeup(&p->p_refcount);
+		}
+	} else
+		panic("proc_rele_locked  -ve ref\n");
+
+}
 
 proc_t
-proc_refinternal(proc_t p, int funneled)
+proc_find_zombref(int pid)
 {
+	proc_t p1 = PROC_NULL;
+	proc_t p = PROC_NULL;
 
-	proc_t p1 = p;
-	boolean_t funnel_state = TRUE; 	/* need to init just to avoid warnings and build failure */
+	proc_list_lock();
 
-	if (funneled == 0)
-		funnel_state = thread_funnel_set(kernel_flock,TRUE);
-	
-	if ((p != PROC_NULL) &&(p->p_stat != SZOMB) && ((p->p_lflag & (P_LREFDRAINWAIT | P_LREFDRAIN | P_LREFDEAD)) == 0))
-		p->p_internalref++;
-	else 
+	p = pfind_locked(pid);
+
+	/* if process still in creation return NULL */
+	if ((p == PROC_NULL) || ((p->p_listflag & P_LIST_INCREATE) != 0)) {
+		proc_list_unlock();
+		return (p1);
+	}
+
+	/* if process has not started exit or  is being reaped, return NULL */
+	if (((p->p_listflag & P_LIST_EXITED) != 0) && ((p->p_listflag & P_LIST_WAITING) == 0)) {
+		p->p_listflag |=  P_LIST_WAITING;
+		p1 = p;
+	} else 
 		p1 = PROC_NULL;
 
-	if (funneled == 0)
-		thread_funnel_set(kernel_flock,funnel_state);
+	proc_list_unlock();
+
 	return(p1);
 }
 
 void
-proc_dropinternal(proc_t p, int funneled)
+proc_drop_zombref(proc_t p)
+{
+	proc_list_lock();
+	if ((p->p_listflag & P_LIST_WAITING) ==  P_LIST_WAITING) {
+		p->p_listflag &= ~P_LIST_WAITING;
+		wakeup(&p->p_stat);
+	}
+	proc_list_unlock();
+}
+
+
+void
+proc_refdrain(proc_t p)
+{
+
+	proc_list_lock();
+
+	p->p_listflag |= P_LIST_DRAIN;
+	while (p->p_refcount) {
+		p->p_listflag |= P_LIST_DRAINWAIT;
+		msleep(&p->p_refcount, proc_list_mlock, 0, "proc_refdrain", 0) ;
+	}
+	p->p_listflag &= ~P_LIST_DRAIN;
+	p->p_listflag |= P_LIST_DEAD;
+
+	proc_list_unlock();
+
+
+}
+
+proc_t 
+proc_parentholdref(proc_t p)
 {
-	boolean_t funnel_state = TRUE; /* need to init just to avoid warnings and build failure */
+	proc_t parent = PROC_NULL;
+	proc_t pp;
+	int loopcnt = 0;
 
-	if (funneled == 0)
-		funnel_state = thread_funnel_set(kernel_flock,TRUE);
 
-	if (p->p_internalref > 0) {
-		p->p_internalref--;
-		if ((p->p_internalref == 0) && ((p->p_lflag & P_LREFDRAINWAIT) == P_LREFDRAINWAIT)) {
-			p->p_lflag &= ~P_LREFDRAINWAIT;
-			wakeup(&p->p_internalref);
+	proc_list_lock();
+loop:
+	pp = p->p_pptr;
+	if ((pp == PROC_NULL) || (pp->p_stat == SZOMB) || ((pp->p_listflag & (P_LIST_CHILDDRSTART | P_LIST_CHILDDRAINED)) == (P_LIST_CHILDDRSTART | P_LIST_CHILDDRAINED))) {
+		parent = PROC_NULL;
+		goto out;
+	}
+		
+	if ((pp->p_listflag & (P_LIST_CHILDDRSTART | P_LIST_CHILDDRAINED)) == P_LIST_CHILDDRSTART) {
+		pp->p_listflag |= P_LIST_CHILDDRWAIT;
+		msleep(&pp->p_childrencnt, proc_list_mlock, 0, "proc_parent", 0);
+		loopcnt++;
+		if (loopcnt == 5) {
+			parent = PROC_NULL;
+			goto out;
+		}
+		goto loop;
+	}
+
+	if ((pp->p_listflag & (P_LIST_CHILDDRSTART | P_LIST_CHILDDRAINED)) == 0) {
+		pp->p_parentref++;
+		parent = pp;
+		goto out;
+	}
+	
+out:
+	proc_list_unlock();
+	return(parent);
+}
+int 
+proc_parentdropref(proc_t p, int listlocked)
+{
+	if (listlocked == 0)
+		proc_list_lock();
+
+	if (p->p_parentref > 0) {
+		p->p_parentref--;
+		if ((p->p_parentref == 0) && ((p->p_listflag & P_LIST_PARENTREFWAIT) == P_LIST_PARENTREFWAIT)) {
+			p->p_listflag &= ~P_LIST_PARENTREFWAIT;
+			wakeup(&p->p_parentref);
 		}
 	} else
-		printf("proc_dropreg -ve ref\n");
+		panic("proc_parentdropref  -ve ref\n");
+	if (listlocked == 0)
+		proc_list_unlock();
+
+	return(0);
+}
+
+void
+proc_childdrainstart(proc_t p)
+{
+#if __PROC_INTERNAL_DEBUG
+	if ((p->p_listflag & P_LIST_CHILDDRSTART) == P_LIST_CHILDDRSTART)
+		panic("proc_childdrainstart: childdrain already started\n");
+#endif
+	p->p_listflag |= P_LIST_CHILDDRSTART;
+	/* wait for all that hold parentrefs to drop */
+	while (p->p_parentref > 0) {
+		p->p_listflag |= P_LIST_PARENTREFWAIT;
+		msleep(&p->p_parentref, proc_list_mlock, 0, "proc_childdrainstart", 0) ;
+	}
+}
+
 
-	if (funneled == 0)
-		thread_funnel_set(kernel_flock,funnel_state);
+void
+proc_childdrainend(proc_t p)
+{
+#if __PROC_INTERNAL_DEBUG
+	if (p->p_childrencnt > 0)
+		panic("exiting: children stil hanging around\n");
+#endif
+	p->p_listflag |= P_LIST_CHILDDRAINED;
+	if ((p->p_listflag & (P_LIST_CHILDLKWAIT |P_LIST_CHILDDRWAIT)) != 0) {
+		p->p_listflag &= ~(P_LIST_CHILDLKWAIT |P_LIST_CHILDDRWAIT);
+		wakeup(&p->p_childrencnt);
+	}
 }
 
+void
+proc_checkdeadrefs(__unused proc_t p)
+{
+#if __PROC_INTERNAL_DEBUG
+	if ((p->p_listflag  & P_LIST_INHASH) != 0)
+		panic("proc being freed and still in hash %p: %u\n", p, p->p_listflag);
+	if (p->p_childrencnt != 0)
+		panic("proc being freed and pending children cnt %p:%d\n", p, p->p_childrencnt);
+	if (p->p_refcount != 0)
+		panic("proc being freed and pending refcount %p:%d\n", p, p->p_refcount);
+	if (p->p_parentref != 0)
+		panic("proc being freed and pending parentrefs %p:%d\n", p, p->p_parentref);
+#endif
+}
 
 int
 proc_pid(proc_t p)
@@ -302,48 +599,76 @@ proc_pid(proc_t p)
 int 
 proc_ppid(proc_t p)
 {
-	if (p->p_pptr != (struct proc *)0) 
-		return(p->p_pptr->p_pid);
-	return(0);
+		return(p->p_ppid);
 }
 
 int 
 proc_selfpid(void)
 {
-	struct proc *p = current_proc();
+	proc_t p = current_proc();
 	return(p->p_pid);
 }
 
-
 int 
 proc_selfppid(void)
 {
-	struct proc *p = current_proc();
-	if (p->p_pptr)
-		return(p->p_pptr->p_pid);
-	else
-		return(0);
+	proc_t p = current_proc();
+	return(p->p_ppid);
+}
+
+proc_t 
+proc_parent(proc_t p)
+{
+	proc_t parent;
+	proc_t pp;
+
+	proc_list_lock();
+loop:
+	pp = p->p_pptr;
+	parent =  proc_ref_locked(pp);
+	if ((parent == PROC_NULL) && (pp != PROC_NULL) && (pp->p_stat != SZOMB) && ((pp->p_listflag & P_LIST_EXITED) != 0) && ((pp->p_listflag & P_LIST_CHILDDRAINED)== 0)){
+		pp->p_listflag |= P_LIST_CHILDLKWAIT;
+		msleep(&pp->p_childrencnt, proc_list_mlock, 0, "proc_parent", 0);
+		goto loop;
+	}
+	proc_list_unlock();
+	return(parent);
 }
 
+
 void
 proc_name(int pid, char * buf, int size)
 {
-	struct proc  *p;
+	proc_t p;
 
-	if ((p = pfind(pid))!= (struct proc *)0) {
-		strncpy(buf, &p->p_comm[0], size);
-		buf[size-1] = 0;
+	if ((p = proc_find(pid)) != PROC_NULL) {
+		strlcpy(buf, &p->p_comm[0], size);
+		proc_rele(p);
 	}
 }
 
+void
+proc_name_kdp(task_t t, char * buf, int size)
+{
+	proc_t p = get_bsdtask_info(t);
+
+	if (p != PROC_NULL)
+		strlcpy(buf, &p->p_comm[0], size);
+}
+
+char *
+proc_name_address(void *p)
+{
+	return &((proc_t)p)->p_comm[0];
+}
+
 void
 proc_selfname(char * buf, int  size)
 {
-	struct proc  *p;
+	proc_t p;
 
-	if ((p = current_proc())!= (struct proc *)0) {
-		strncpy(buf, &p->p_comm[0], size);
-		buf[size-1] = 0;
+	if ((p = current_proc())!= (proc_t)0) {
+		strlcpy(buf, &p->p_comm[0], size);
 	}
 }
 
@@ -352,8 +677,9 @@ proc_signal(int pid, int signum)
 {
 	proc_t p;
 
-	if ((p = pfind(pid))!= (struct proc *)0) {
+	if ((p = proc_find(pid)) != PROC_NULL) {
 			psignal(p, signum);
+			proc_rele(p);
 	}	
 }
 
@@ -361,11 +687,14 @@ int
 proc_issignal(int pid, sigset_t mask)
 {
 	proc_t p;
+	int error=0;
 
-	if ((p = pfind(pid))!= (struct proc *)0) {
-		return(proc_pendingsignals(p, mask));
+	if ((p = proc_find(pid)) != PROC_NULL) {
+		error = proc_pendingsignals(p, mask);
+		proc_rele(p);
 	}	
-	return(0);
+
+	return(error);
 }
 
 int
@@ -385,11 +714,10 @@ proc_exiting(proc_t p)
 	int retval = 0;
 
 	if (p)
-		retval = p->p_flag & P_WEXIT;
+		retval = p->p_lflag & P_LEXIT;
 	return(retval? 1: 0);
 }
 
-
 int
 proc_forcequota(proc_t p)
 {
@@ -415,16 +743,54 @@ proc_tbe(proc_t p)
 int
 proc_suser(proc_t p)
 {
-	return(suser(p->p_ucred, NULL));
-	
+	kauth_cred_t my_cred;
+	int error;
+
+	my_cred = kauth_cred_proc_ref(p);
+	error = suser(my_cred, &p->p_acflag);
+	kauth_cred_unref(&my_cred);
+	return(error);
+}
+
+task_t
+proc_task(proc_t proc)
+{
+	return (task_t)proc->task;
 }
 
+/*      
+ * Obtain the first thread in a process
+ *
+ * XXX This is a bad thing to do; it exists predominantly to support the
+ * XXX use of proc_t's in places that should really be using
+ * XXX thread_t's instead.  This maintains historical behaviour, but really
+ * XXX needs an audit of the context (proxy vs. not) to clean up.
+ */
+thread_t
+proc_thread(proc_t proc)                                                
+{           
+        uthread_t uth = TAILQ_FIRST(&proc->p_uthlist);
+
+        if (uth != NULL)
+                return(uth->uu_context.vc_thread);
+
+	return(NULL);
+}       
+
 kauth_cred_t
 proc_ucred(proc_t p)
 {
 	return(p->p_ucred);
 }
 
+struct uthread *
+current_uthread()
+{
+	thread_t th = current_thread();
+
+	return((struct uthread *)get_bsdthread_info(th));
+}
+
 
 int
 proc_is64bit(proc_t p)
@@ -432,7 +798,51 @@ proc_is64bit(proc_t p)
 	return(IS_64BIT_PROCESS(p));
 }
 
-/* LP64todo - figure out how to identify 64-bit processes if NULL procp */
+int
+proc_pidversion(proc_t p)
+{
+	return(p->p_idversion);
+}
+
+uint64_t
+proc_uniqueid(proc_t p)
+{
+	return(p->p_uniqueid);
+}
+
+uint64_t
+proc_selfuniqueid(void)
+{
+	proc_t p = current_proc();
+	return(p->p_uniqueid);
+}
+
+int
+proc_getcdhash(proc_t p, unsigned char *cdhash)
+{
+	return vn_getcdhash(p->p_textvp, p->p_textoff, cdhash);
+}
+
+void
+proc_getexecutableuuid(proc_t p, unsigned char *uuidbuf, unsigned long size)
+{
+	if (size >= sizeof(p->p_uuid)) {
+		memcpy(uuidbuf, p->p_uuid, sizeof(p->p_uuid));
+	}
+}
+
+
+void
+bsd_set_dependency_capable(task_t task)
+{
+    proc_t p = get_bsdtask_info(task);
+
+    if (p) {
+	OSBitOrAtomic(P_DEPENDENCY_CAPABLE, &p->p_flag);
+    }
+}
+
+
 int
 IS_64BIT_PROCESS(proc_t p)
 {
@@ -442,48 +852,79 @@ IS_64BIT_PROCESS(proc_t p)
 		return(0);
 }
 
-
 /*
  * Locate a process by number
  */
-struct proc *
-pfind(pid)
-	register pid_t pid;
+proc_t
+pfind_locked(pid_t pid)
 {
-	register struct proc *p;
+	proc_t p;
+#if DEBUG
+	proc_t q;
+#endif
 
 	if (!pid)
 		return (kernproc);
 
-	for (p = PIDHASH(pid)->lh_first; p != 0; p = p->p_hash.le_next)
-		if (p->p_pid == pid)
+	for (p = PIDHASH(pid)->lh_first; p != 0; p = p->p_hash.le_next) {
+		if (p->p_pid == pid) {
+#if DEBUG
+			for (q = p->p_hash.le_next; q != 0; q = q->p_hash.le_next) {
+				if ((p !=q) && (q->p_pid == pid))	
+					panic("two procs with same pid %p:%p:%d:%d\n", p, q, p->p_pid, q->p_pid);
+			}
+#endif
 			return (p);
+		}
+	}
 	return (NULL);
 }
 
 /*
  * Locate a zombie by PID
  */
-__private_extern__ struct proc *
-pzfind(pid)
-	register pid_t pid;
+__private_extern__ proc_t
+pzfind(pid_t pid)
 {
-	register struct proc *p;
+	proc_t p;
+
+
+	proc_list_lock();
 
 	for (p = zombproc.lh_first; p != 0; p = p->p_list.le_next)
 		if (p->p_pid == pid)
-			return (p);
-	return (NULL);
+			break;
+
+	proc_list_unlock();
+
+	return (p);
 }
 
 /*
  * Locate a process group by number
  */
+
 struct pgrp *
-pgfind(pgid)
-	register pid_t pgid;
+pgfind(pid_t pgid)
 {
-	register struct pgrp *pgrp;
+	struct pgrp * pgrp;
+
+	proc_list_lock();
+	pgrp = pgfind_internal(pgid);
+	if ((pgrp == NULL) || ((pgrp->pg_listflags & PGRP_FLAG_TERMINATE) != 0))
+		pgrp = PGRP_NULL;
+	else
+		pgrp->pg_refcount++;
+	proc_list_unlock();
+	return(pgrp);
+}
+
+
+
+struct pgrp *
+pgfind_internal(pid_t pgid)
+{
+	struct pgrp *pgrp;
 
 	for (pgrp = PGRPHASH(pgid)->lh_first; pgrp != 0; pgrp = pgrp->pg_hash.le_next)
 		if (pgrp->pg_id == pgid)
@@ -491,27 +932,108 @@ pgfind(pgid)
 	return (NULL);
 }
 
+void
+pg_rele(struct pgrp * pgrp)
+{
+	if(pgrp == PGRP_NULL)
+		return;
+	pg_rele_dropref(pgrp);
+}
+
+void
+pg_rele_dropref(struct pgrp * pgrp)
+{
+	proc_list_lock();
+	if ((pgrp->pg_refcount == 1) && ((pgrp->pg_listflags & PGRP_FLAG_TERMINATE) == PGRP_FLAG_TERMINATE)) {
+		proc_list_unlock();
+		pgdelete_dropref(pgrp);
+		return;
+	}
+
+	pgrp->pg_refcount--;
+	proc_list_unlock();
+}
+
+struct session *
+session_find_internal(pid_t sessid)
+{
+	struct session *sess;
+
+	for (sess = SESSHASH(sessid)->lh_first; sess != 0; sess = sess->s_hash.le_next)
+		if (sess->s_sid == sessid)
+			return (sess);
+	return (NULL);
+}
+
+
+/*
+ * Make a new process ready to become a useful member of society by making it
+ * visible in all the right places and initialize its own lists to empty.
+ *
+ * Parameters:	parent			The parent of the process to insert
+ *		child			The child process to insert
+ *
+ * Returns:	(void)
+ *
+ * Notes:	Insert a child process into the parents process group, assign
+ *		the child the parent process pointer and PPID of the parent,
+ *		place it on the parents p_children list as a sibling,
+ *		initialize its own child list, place it in the allproc list,
+ *		insert it in the proper hash bucket, and initialize its
+ *		event list.
+ */
+void
+pinsertchild(proc_t parent, proc_t child)
+{
+	struct pgrp * pg;
+
+	LIST_INIT(&child->p_children);
+	TAILQ_INIT(&child->p_evlist);
+	child->p_pptr = parent;
+	child->p_ppid = parent->p_pid;
+
+	pg = proc_pgrp(parent);
+	pgrp_add(pg, parent, child);
+	pg_rele(pg);
+
+	proc_list_lock();
+	parent->p_childrencnt++;
+	LIST_INSERT_HEAD(&parent->p_children, child, p_sibling);
+
+	LIST_INSERT_HEAD(&allproc, child, p_list);
+	/* mark the completion of proc creation */
+	child->p_listflag &= ~P_LIST_INCREATE;
+
+	proc_list_unlock();
+
+}
 
 /*
  * Move p to a new or existing process group (and session)
+ *
+ * Returns:	0			Success
+ *		ESRCH			No such process
  */
 int
-enterpgrp(p, pgid, mksess)
-	register struct proc *p;
-	pid_t pgid;
-	int mksess;
+enterpgrp(proc_t p, pid_t pgid, int mksess)
 {
-	register struct pgrp *pgrp = pgfind(pgid);
+	struct pgrp *pgrp;
+	struct pgrp *mypgrp;
+	struct session * procsp;
+
+	pgrp = pgfind(pgid);
+	mypgrp = proc_pgrp(p);
+	procsp = proc_session(p);
 
 #if DIAGNOSTIC
 	if (pgrp != NULL && mksess)	/* firewalls */
 		panic("enterpgrp: setsid into non-empty pgrp");
-	if (SESS_LEADER(p))
+	if (SESS_LEADER(p, procsp))
 		panic("enterpgrp: session leader attempted setpgrp");
 #endif
-	if (pgrp == NULL) {
+	if (pgrp == PGRP_NULL) {
 		pid_t savepid = p->p_pid;
-		struct proc *np;
+		proc_t np = PROC_NULL;
 		/*
 		 * new process group
 		 */
@@ -523,12 +1045,19 @@ enterpgrp(p, pgid, mksess)
 		    M_WAITOK);
 		if (pgrp == NULL)
 			panic("enterpgrp: M_PGRP zone depleted");
-		if ((np = pfind(savepid)) == NULL || np != p) {
+		if ((np = proc_find(savepid)) == NULL || np != p) {
+			if (np != PROC_NULL)
+				proc_rele(np);
+			if (mypgrp != PGRP_NULL)
+				pg_rele(mypgrp);
+			if (procsp != SESSION_NULL)
+				session_rele(procsp);
 			FREE_ZONE(pgrp, sizeof(struct pgrp), M_PGRP);
 			return (ESRCH);
 		}
+		proc_rele(np);
 		if (mksess) {
-			register struct session *sess;
+			struct session *sess;
 
 			/*
 			 * new session
@@ -541,87 +1070,176 @@ enterpgrp(p, pgid, mksess)
 			sess->s_sid = p->p_pid;
 			sess->s_count = 1;
 			sess->s_ttyvp = NULL;
-			sess->s_ttyp = NULL;
-			bcopy(p->p_session->s_login, sess->s_login,
+			sess->s_ttyp = TTY_NULL;
+			sess->s_flags = 0;
+			sess->s_listflags = 0;
+			sess->s_ttypgrpid = NO_PID;
+#if CONFIG_FINE_LOCK_GROUPS
+			lck_mtx_init(&sess->s_mlock, proc_mlock_grp, proc_lck_attr);
+#else
+			lck_mtx_init(&sess->s_mlock, proc_lck_grp, proc_lck_attr);
+#endif
+			bcopy(procsp->s_login, sess->s_login,
 			    sizeof(sess->s_login));
-			p->p_flag &= ~P_CONTROLT;
+			OSBitAndAtomic(~((uint32_t)P_CONTROLT), &p->p_flag);
+			proc_list_lock();
+			LIST_INSERT_HEAD(SESSHASH(sess->s_sid), sess, s_hash);
+			proc_list_unlock();
 			pgrp->pg_session = sess;
 #if DIAGNOSTIC
 			if (p != current_proc())
 				panic("enterpgrp: mksession and p != curproc");
 #endif
 		} else {
-			pgrp->pg_session = p->p_session;
+			proc_list_lock();
+			pgrp->pg_session = procsp;
+			
+			if ((pgrp->pg_session->s_listflags & (S_LIST_TERM | S_LIST_DEAD)) != 0)
+				panic("enterpgrp:  providing ref to terminating session ");	
 			pgrp->pg_session->s_count++;
+			proc_list_unlock();
 		}
 		pgrp->pg_id = pgid;
+#if CONFIG_FINE_LOCK_GROUPS
+		lck_mtx_init(&pgrp->pg_mlock, proc_mlock_grp, proc_lck_attr);
+#else
+		lck_mtx_init(&pgrp->pg_mlock, proc_lck_grp, proc_lck_attr);
+#endif
 		LIST_INIT(&pgrp->pg_members);
-		LIST_INSERT_HEAD(PGRPHASH(pgid), pgrp, pg_hash);
+		pgrp->pg_membercnt = 0;
 		pgrp->pg_jobc = 0;
-	} else if (pgrp == p->p_pgrp)
+		proc_list_lock();
+		pgrp->pg_refcount = 1;
+		pgrp->pg_listflags = 0;
+		LIST_INSERT_HEAD(PGRPHASH(pgid), pgrp, pg_hash);
+		proc_list_unlock();
+	} else if (pgrp == mypgrp) {
+		pg_rele(pgrp);
+		if (mypgrp != NULL)
+			pg_rele(mypgrp);
+		if (procsp != SESSION_NULL)
+			session_rele(procsp);
 		return (0);
+	}
 
+	if (procsp != SESSION_NULL)
+		session_rele(procsp);
 	/*
 	 * Adjust eligibility of affected pgrps to participate in job control.
 	 * Increment eligibility counts before decrementing, otherwise we
 	 * could reach 0 spuriously during the first call.
 	 */
 	fixjobc(p, pgrp, 1);
-	fixjobc(p, p->p_pgrp, 0);
+	fixjobc(p, mypgrp, 0);
 
-	LIST_REMOVE(p, p_pglist);
-	if (p->p_pgrp->pg_members.lh_first == 0)
-		pgdelete(p->p_pgrp);
-	p->p_pgrp = pgrp;
-	LIST_INSERT_HEAD(&pgrp->pg_members, p, p_pglist);
-	return (0);
+	if(mypgrp != PGRP_NULL)
+		pg_rele(mypgrp);
+	pgrp_replace(p, pgrp);
+	pg_rele(pgrp);
+
+	return(0);
 }
 
 /*
  * remove process from process group
  */
 int
-leavepgrp(p)
-	register struct proc *p;
+leavepgrp(proc_t p)
 {
 
-	LIST_REMOVE(p, p_pglist);
-	if (p->p_pgrp->pg_members.lh_first == 0)
-		pgdelete(p->p_pgrp);
-	p->p_pgrp = 0;
+	pgrp_remove(p);
 	return (0);
 }
 
 /*
  * delete a process group
  */
-void
-pgdelete(pgrp)
-	register struct pgrp *pgrp;
+static void
+pgdelete_dropref(struct pgrp *pgrp)
 {
-	struct tty * ttyp;
+	struct tty *ttyp;
+	int emptypgrp  = 1;
+	struct session *sessp;
+
+
+	pgrp_lock(pgrp);
+	if (pgrp->pg_membercnt != 0) {
+		emptypgrp = 0;
+	}
+	pgrp_unlock(pgrp);
+
+	proc_list_lock();
+	pgrp->pg_refcount--;
+	if ((emptypgrp == 0) || (pgrp->pg_membercnt != 0)) {
+		proc_list_unlock();
+		return;
+	}
 
-	ttyp = pgrp->pg_session->s_ttyp;
-	if (ttyp != NULL && pgrp->pg_session->s_ttyp->t_pgrp == pgrp) {
-		pgrp->pg_session->s_ttyp->t_pgrp = NULL;
+	pgrp->pg_listflags |= PGRP_FLAG_TERMINATE;
+	
+	if (pgrp->pg_refcount > 0) {
+		proc_list_unlock();
+		return;
 	}
+
+	pgrp->pg_listflags |= PGRP_FLAG_DEAD;
 	LIST_REMOVE(pgrp, pg_hash);
-	if (--pgrp->pg_session->s_count == 0) {
-		if (ttyp != NULL && (ttyp->t_session == pgrp->pg_session))
-			ttyp->t_session = 0;
-		FREE_ZONE(pgrp->pg_session, sizeof(struct session), M_SESSION);
+
+	proc_list_unlock();
+	
+	ttyp = SESSION_TP(pgrp->pg_session);
+	if (ttyp != TTY_NULL) {
+		if (ttyp->t_pgrp == pgrp) {
+			tty_lock(ttyp);
+			/* Re-check after acquiring the lock */
+			if (ttyp->t_pgrp == pgrp) {
+				ttyp->t_pgrp = NULL;
+				pgrp->pg_session->s_ttypgrpid = NO_PID;
+			}
+			tty_unlock(ttyp);
+		}
 	}
-	FREE_ZONE(pgrp, sizeof *pgrp, M_PGRP);
-}
 
-void
-sessrele(sess)
-	struct session *sess;
-{
-	if (--sess->s_count == 0)
-		FREE_ZONE(sess, sizeof (struct session), M_SESSION);
+	proc_list_lock();
+
+	sessp = pgrp->pg_session;
+	if ((sessp->s_listflags & (S_LIST_TERM | S_LIST_DEAD)) != 0)
+			panic("pg_deleteref: manipulating refs of already terminating session");
+	if (--sessp->s_count == 0) {
+		if ((sessp->s_listflags & (S_LIST_TERM | S_LIST_DEAD)) != 0)
+			panic("pg_deleteref: terminating already terminated session");
+		sessp->s_listflags |= S_LIST_TERM;
+		ttyp = SESSION_TP(sessp);
+		LIST_REMOVE(sessp, s_hash);
+		proc_list_unlock();
+		if (ttyp != TTY_NULL) {
+			tty_lock(ttyp);
+			if (ttyp->t_session == sessp)
+				ttyp->t_session = NULL;
+			tty_unlock(ttyp);
+		}
+		proc_list_lock();
+		sessp->s_listflags |= S_LIST_DEAD;
+		if (sessp->s_count != 0)
+			panic("pg_deleteref: freeing session in use");	
+		proc_list_unlock();
+#if CONFIG_FINE_LOCK_GROUPS
+		lck_mtx_destroy(&sessp->s_mlock, proc_mlock_grp);
+#else
+		lck_mtx_destroy(&sessp->s_mlock, proc_lck_grp);
+#endif
+		FREE_ZONE(sessp, sizeof(struct session), M_SESSION);
+	} else
+		proc_list_unlock();
+#if CONFIG_FINE_LOCK_GROUPS
+	lck_mtx_destroy(&pgrp->pg_mlock, proc_mlock_grp);
+#else
+	lck_mtx_destroy(&pgrp->pg_mlock, proc_lck_grp);
+#endif
+	FREE_ZONE(pgrp, sizeof(*pgrp), M_PGRP);
 }
 
+
 /*
  * Adjust pgrp jobc counters when specified process changes process group.
  * We count the number of processes in each process group that "qualify"
@@ -632,38 +1250,90 @@ sessrele(sess)
  * entering == 0 => p is leaving specified group.
  * entering == 1 => p is entering specified group.
  */
+int
+fixjob_callback(proc_t p, void * arg)
+{
+	struct fixjob_iterargs *fp;
+	struct pgrp * pg, *hispg;
+	struct session * mysession, *hissess;
+	int entering;
+
+	fp = (struct fixjob_iterargs *)arg;
+	pg = fp->pg;
+	mysession = fp->mysession;
+	entering = fp->entering;
+
+	hispg = proc_pgrp(p);
+	hissess = proc_session(p);
+
+	if ((hispg  != pg) &&
+	    (hissess == mysession)) {
+		pgrp_lock(hispg);
+		if (entering) {
+			hispg->pg_jobc++;
+			pgrp_unlock(hispg);
+		} else if (--hispg->pg_jobc == 0) {
+			pgrp_unlock(hispg);
+			orphanpg(hispg);
+		} else
+			pgrp_unlock(hispg);
+	}
+	if (hissess != SESSION_NULL)
+		session_rele(hissess);
+	if (hispg != PGRP_NULL)
+		pg_rele(hispg);
+
+	return(PROC_RETURNED);
+}
+
 void
-fixjobc(struct proc *p, struct pgrp *pgrp, int entering)
+fixjobc(proc_t p, struct pgrp *pgrp, int entering)
 {
-	register struct pgrp *hispgrp;
-	register struct session *mysession = pgrp->pg_session;
+	struct pgrp *hispgrp = PGRP_NULL;
+	struct session *hissess = SESSION_NULL;
+	struct session *mysession = pgrp->pg_session;
+	proc_t parent;
+	struct fixjob_iterargs fjarg;
+
+	parent = proc_parent(p);
+	if (parent != PROC_NULL) {
+		hispgrp = proc_pgrp(parent);	
+		hissess = proc_session(parent);
+		proc_rele(parent);
+	}
+
 
 	/*
 	 * Check p's parent to see whether p qualifies its own process
 	 * group; if so, adjust count for p's process group.
 	 */
-	if ((hispgrp = p->p_pptr->p_pgrp) != pgrp &&
-	    hispgrp->pg_session == mysession) {
-		if (entering)
+	if ((hispgrp != pgrp) &&
+	    (hissess == mysession)) {
+		pgrp_lock(pgrp);
+		if (entering) {
 			pgrp->pg_jobc++;
-		else if (--pgrp->pg_jobc == 0)
+			pgrp_unlock(pgrp);
+		 }else if (--pgrp->pg_jobc == 0) {
+			pgrp_unlock(pgrp);
 			orphanpg(pgrp);
+		} else
+			pgrp_unlock(pgrp);
 	}
 
+	if (hissess != SESSION_NULL)
+		session_rele(hissess);
+	if (hispgrp != PGRP_NULL)
+		pg_rele(hispgrp);
+
 	/*
 	 * Check this process' children to see whether they qualify
 	 * their process groups; if so, adjust counts for children's
 	 * process groups.
 	 */
-	for (p = p->p_children.lh_first; p != 0; p = p->p_sibling.le_next)
-		if ((hispgrp = p->p_pgrp) != pgrp &&
-		    hispgrp->pg_session == mysession &&
-		    p->p_stat != SZOMB) {
-			if (entering)
-				hispgrp->pg_jobc++;
-			else if (--hispgrp->pg_jobc == 0)
-				orphanpg(hispgrp);
-		}
+	fjarg.pg = pgrp;
+	fjarg.mysession = mysession;
+	fjarg.entering = entering;
+	proc_childrenwalk(p, fixjob_callback, &fjarg);
 }
 
 /* 
@@ -672,61 +1342,83 @@ fixjobc(struct proc *p, struct pgrp *pgrp, int entering)
  * hang-up all process in that group.
  */
 static void
-orphanpg(struct pgrp *pg)
+orphanpg(struct pgrp * pgrp)
 {
-	register struct proc *p;
-
-	for (p = pg->pg_members.lh_first; p != 0; p = p->p_pglist.le_next) {
+	proc_t p;
+	pid_t * pid_list;
+	int count, pidcount, i, alloc_count;
+
+	if (pgrp == PGRP_NULL)
+		return;
+	count = 0;
+	pgrp_lock(pgrp);
+	for (p = pgrp->pg_members.lh_first; p != 0; p = p->p_pglist.le_next) {
 		if (p->p_stat == SSTOP) {
-			for (p = pg->pg_members.lh_first; p != 0;
-			    p = p->p_pglist.le_next) {
-				pt_setrunnable(p);
-				psignal(p, SIGHUP);
-				psignal(p, SIGCONT);
-			}
-			return;
+			for (p = pgrp->pg_members.lh_first; p != 0;
+				p = p->p_pglist.le_next) 
+				count++;
+			break;	/* ??? stops after finding one.. */
 		}
 	}
-}
-
-#ifdef DEBUG
-void pgrpdump(void);	/* forward declare here (called from debugger) */
-
-void
-pgrpdump(void)
-{
-	struct pgrp *pgrp;
-	struct proc *p;
-	u_long i;
-
-	for (i = 0; i <= pgrphash; i++) {
-		if ((pgrp = pgrphashtbl[i].lh_first) != NULL) {
-			printf("\tindx %d\n", i);
-			for (; pgrp != 0; pgrp = pgrp->pg_hash.le_next) {
-				printf("\tpgrp 0x%08x, pgid %d, sess %p, sesscnt %d, mem %p\n",
-				    pgrp, pgrp->pg_id, pgrp->pg_session,
-				    pgrp->pg_session->s_count,
-				    pgrp->pg_members.lh_first);
-				for (p = pgrp->pg_members.lh_first; p != 0;
-				    p = p->p_pglist.le_next) {
-					printf("\t\tpid %d addr 0x%08x pgrp 0x%08x\n", 
-					    p->p_pid, p, p->p_pgrp);
-				}
+	pgrp_unlock(pgrp);
+
+	count += 20;
+	if (count > hard_maxproc)
+		count = hard_maxproc;
+	alloc_count = count * sizeof(pid_t);
+	pid_list = (pid_t *)kalloc(alloc_count);
+	bzero(pid_list, alloc_count);
+	
+	pidcount = 0;
+	pgrp_lock(pgrp);
+	for (p = pgrp->pg_members.lh_first; p != 0;
+	     p = p->p_pglist.le_next) {
+		if (p->p_stat == SSTOP) {
+			for (p = pgrp->pg_members.lh_first; p != 0;
+				p = p->p_pglist.le_next) {
+				pid_list[pidcount] = p->p_pid;
+				pidcount++;
+				if (pidcount >= count)
+					break;
 			}
+			break; /* ??? stops after finding one.. */
+		}
+	}
+	pgrp_unlock(pgrp);
+		
+	if (pidcount == 0)
+		goto out;
+
+
+	for (i = 0; i< pidcount; i++) {
+		/* No handling or proc0 */
+		if (pid_list[i] == 0)
+			continue;
+		p = proc_find(pid_list[i]);
+		if (p) {
+			proc_transwait(p, 0);
+			pt_setrunnable(p);
+			psignal(p, SIGHUP);
+			psignal(p, SIGCONT);
+			proc_rele(p);
 		}
 	}
+out:
+	kfree(pid_list, alloc_count);
+	return;
 }
-#endif /* DEBUG */
+
+
 
 /* XXX should be __private_extern__ */
 int
-proc_is_classic(struct proc *p)
+proc_is_classic(proc_t p)
 {
     return (p->p_flag & P_TRANSLATED) ? 1 : 0;
 }
 
 /* XXX Why does this function exist?  Need to kill it off... */
-struct proc *
+proc_t
 current_proc_EXTERNAL(void)
 {
 	return (current_proc());
@@ -743,19 +1435,19 @@ current_proc_EXTERNAL(void)
  * by using "/dev/null", or all core files can be stored in "/cores/%U/%N-%P".
  * This is controlled by the sysctl variable kern.corefile (see above).
  */
-__private_extern__ char *
-proc_core_name(const char *name, uid_t uid, pid_t pid)
+__private_extern__ int
+proc_core_name(const char *name, uid_t uid, pid_t pid, char *cf_name,
+		size_t cf_name_len)
 {
 	const char *format, *appendstr;
-	char *temp;
 	char id_buf[11];		/* Buffer for pid/uid -- max 4B */
 	size_t i, l, n;
 
+	if (cf_name == NULL)
+		goto toolong;
+
 	format = corefilename;
-	MALLOC(temp, char *, MAXPATHLEN, M_TEMP, M_NOWAIT | M_ZERO);
-	if (temp == NULL)
-		return (NULL);
-	for (i = 0, n = 0; n < MAXPATHLEN && format[i]; i++) {
+	for (i = 0, n = 0; n < cf_name_len && format[i]; i++) {
 		switch (format[i]) {
 		case '%':	/* Format character */
 			i++;
@@ -767,11 +1459,11 @@ proc_core_name(const char *name, uid_t uid, pid_t pid)
 				appendstr = name;
 				break;
 			case 'P':	/* process id */
-				sprintf(id_buf, "%u", pid);
+				snprintf(id_buf, sizeof(id_buf), "%u", pid);
 				appendstr = id_buf;
 				break;
 			case 'U':	/* user id */
-				sprintf(id_buf, "%u", uid);
+				snprintf(id_buf, sizeof(id_buf), "%u", uid);
 				appendstr = id_buf;
 				break;
 			default:
@@ -781,21 +1473,1574 @@ proc_core_name(const char *name, uid_t uid, pid_t pid)
 				    format[i], format);
 			}
 			l = strlen(appendstr);
-			if ((n + l) >= MAXPATHLEN)
+			if ((n + l) >= cf_name_len)
 				goto toolong;
-			bcopy(appendstr, temp + n, l);
+			bcopy(appendstr, cf_name + n, l);
 			n += l;
 			break;
 		default:
-			temp[n++] = format[i];
+			cf_name[n++] = format[i];
 		}
 	}
 	if (format[i] != '\0')
 		goto toolong;
-	return (temp);
+	return (0);
 toolong:
-	log(LOG_ERR, "pid %ld (%s), uid (%lu): corename is too long\n",
-	    (long)pid, name, (u_long)uid);
-	FREE(temp, M_TEMP);
-	return (NULL);
+	log(LOG_ERR, "pid %ld (%s), uid (%u): corename is too long\n",
+	    (long)pid, name, (uint32_t)uid);
+	return (1);
+}
+
+#if CONFIG_LCTX
+
+static void
+lctxinit(void)
+{
+	LIST_INIT(&alllctx);
+	alllctx_cnt = 0;
+
+	/* allocate lctx lock group attribute and group */
+	lctx_lck_grp_attr = lck_grp_attr_alloc_init();
+	lck_grp_attr_setstat(lctx_lck_grp_attr);
+
+	lctx_lck_grp = lck_grp_alloc_init("lctx", lctx_lck_grp_attr);
+	/* Allocate lctx lock attribute */
+	lctx_lck_attr = lck_attr_alloc_init();
+
+	lck_mtx_init(&alllctx_lock, lctx_lck_grp, lctx_lck_attr);
+}
+
+/*
+ * Locate login context by number.
+ */
+struct lctx *
+lcfind(pid_t lcid)
+{
+	struct lctx *l;
+
+	ALLLCTX_LOCK;
+	LIST_FOREACH(l, &alllctx, lc_list) {
+		if (l->lc_id == lcid) {
+			LCTX_LOCK(l);
+			break;
+		}
+	}
+	ALLLCTX_UNLOCK;
+	return (l);
+}
+
+#define	LCID_INC				\
+	do {					\
+		lastlcid++;			\
+		if (lastlcid > maxlcid)	\
+			lastlcid = 1;		\
+	} while (0)				\
+
+struct lctx *
+lccreate(void)
+{
+	struct lctx *l;
+	pid_t newlcid;
+
+	/* Not very efficient but this isn't a common operation. */
+	while ((l = lcfind(lastlcid)) != NULL) {
+		LCTX_UNLOCK(l);
+		LCID_INC;
+	}
+	newlcid = lastlcid;
+	LCID_INC;
+
+	MALLOC(l, struct lctx *, sizeof(struct lctx), M_LCTX, M_WAITOK|M_ZERO);
+	l->lc_id = newlcid;
+	LIST_INIT(&l->lc_members);
+	lck_mtx_init(&l->lc_mtx, lctx_lck_grp, lctx_lck_attr);
+#if CONFIG_MACF
+	l->lc_label = mac_lctx_label_alloc();
+#endif
+	ALLLCTX_LOCK;
+	LIST_INSERT_HEAD(&alllctx, l, lc_list);
+	alllctx_cnt++;
+	ALLLCTX_UNLOCK;
+
+	return (l);
+}
+
+/*
+ * Call with proc protected (either by being invisible
+ * or by having the all-login-context lock held) and
+ * the lctx locked.
+ *
+ * Will unlock lctx on return.
+ */
+void
+enterlctx (proc_t p, struct lctx *l, __unused int create)
+{
+	if (l == NULL)
+		return;
+
+	p->p_lctx = l;
+	LIST_INSERT_HEAD(&l->lc_members, p, p_lclist);
+	l->lc_mc++;
+
+#if CONFIG_MACF
+	if (create)
+		mac_lctx_notify_create(p, l);
+	else
+		mac_lctx_notify_join(p, l);
+#endif
+	LCTX_UNLOCK(l);
+
+	return;
+}
+
+/*
+ * Remove process from login context (if any). Called with p protected by
+ * the alllctx lock.
+ */
+void
+leavelctx (proc_t p)
+{
+	struct lctx *l;
+
+	if (p->p_lctx == NULL) {
+		return;
+	}
+
+	LCTX_LOCK(p->p_lctx);
+	l = p->p_lctx;
+	p->p_lctx = NULL;
+	LIST_REMOVE(p, p_lclist);
+	l->lc_mc--;
+#if CONFIG_MACF
+	mac_lctx_notify_leave(p, l);
+#endif
+	if (LIST_EMPTY(&l->lc_members)) {
+		LIST_REMOVE(l, lc_list);
+		alllctx_cnt--;
+		LCTX_UNLOCK(l);
+		lck_mtx_destroy(&l->lc_mtx, lctx_lck_grp);
+#if CONFIG_MACF
+		mac_lctx_label_free(l->lc_label);
+		l->lc_label = NULL;
+#endif
+		FREE(l, M_LCTX);
+	} else {
+		LCTX_UNLOCK(l);
+	}
+	return;
+}
+
+static int
+sysctl_kern_lctx SYSCTL_HANDLER_ARGS
+{
+	int *name = (int*) arg1;
+	u_int namelen = arg2;
+	struct kinfo_lctx kil;
+	struct lctx *l;
+	int error;
+
+	error = 0;
+
+	switch (oidp->oid_number) {
+	case KERN_LCTX_ALL:
+		ALLLCTX_LOCK;
+		/* Request for size. */
+		if (!req->oldptr) {
+			error = SYSCTL_OUT(req, 0,
+				sizeof(struct kinfo_lctx) * (alllctx_cnt + 1));
+			goto out;
+		}
+		break;
+
+	case KERN_LCTX_LCID:
+		/* No space */
+		if (req->oldlen < sizeof(struct kinfo_lctx))
+			return (ENOMEM);
+		/* No argument */
+		if (namelen != 1)
+			return (EINVAL);
+		/* No login context */
+		l = lcfind((pid_t)name[0]);
+		if (l == NULL)
+			return (ENOENT);
+		kil.id = l->lc_id;
+		kil.mc = l->lc_mc;
+		LCTX_UNLOCK(l);
+		return (SYSCTL_OUT(req, (caddr_t)&kil, sizeof(kil)));
+
+	default:
+		return (EINVAL);
+	}
+
+	/* Provided buffer is too small. */
+	if (req->oldlen < (sizeof(struct kinfo_lctx) * alllctx_cnt)) {
+		error = ENOMEM;
+		goto out;
+	}
+
+	LIST_FOREACH(l, &alllctx, lc_list) {
+		LCTX_LOCK(l);
+		kil.id = l->lc_id;
+		kil.mc = l->lc_mc;
+		LCTX_UNLOCK(l);
+		error = SYSCTL_OUT(req, (caddr_t)&kil, sizeof(kil));
+		if (error)
+			break;
+	}
+out:
+	ALLLCTX_UNLOCK;
+
+	return (error);
+}
+
+SYSCTL_NODE(_kern, KERN_LCTX, lctx, CTLFLAG_RW|CTLFLAG_LOCKED, 0, "Login Context");
+
+SYSCTL_PROC(_kern_lctx, KERN_LCTX_ALL, all, CTLFLAG_RD|CTLTYPE_STRUCT | CTLFLAG_LOCKED,
+	    0, 0, sysctl_kern_lctx, "S,lctx",
+	    "Return entire login context table");
+SYSCTL_NODE(_kern_lctx, KERN_LCTX_LCID, lcid, CTLFLAG_RD | CTLFLAG_LOCKED,
+	    sysctl_kern_lctx, "Login Context Table");
+SYSCTL_INT(_kern_lctx, OID_AUTO, last,  CTLFLAG_RD | CTLFLAG_LOCKED, &lastlcid, 0, ""); 
+SYSCTL_INT(_kern_lctx, OID_AUTO, count, CTLFLAG_RD | CTLFLAG_LOCKED, &alllctx_cnt, 0, "");
+SYSCTL_INT(_kern_lctx, OID_AUTO, max, CTLFLAG_RW | CTLFLAG_LOCKED, &maxlcid, 0, "");
+
+#endif	/* LCTX */
+
+/* Code Signing related routines */
+
+int 
+csops(__unused proc_t p, struct csops_args *uap, __unused int32_t *retval)
+{
+	return(csops_internal(uap->pid, uap->ops, uap->useraddr, 
+		uap->usersize, USER_ADDR_NULL));
+}
+
+int 
+csops_audittoken(__unused proc_t p, struct csops_audittoken_args *uap, __unused int32_t *retval)
+{
+	if (uap->uaudittoken == USER_ADDR_NULL)
+		return(EINVAL);
+	switch (uap->ops) {
+		case CS_OPS_PIDPATH:
+		case CS_OPS_ENTITLEMENTS_BLOB:
+			break;
+		default:
+			return(EINVAL);
+	};
+
+	return(csops_internal(uap->pid, uap->ops, uap->useraddr, 
+		uap->usersize, uap->uaudittoken));
+}
+
+static int
+csops_internal(pid_t pid, int ops, user_addr_t uaddr, user_size_t usersize, user_addr_t uaudittoken)
+{
+	size_t usize = (size_t)CAST_DOWN(size_t, usersize);
+	proc_t pt;
+	uint32_t retflags;
+	int vid, forself;
+	int error;
+	vnode_t tvp;
+	off_t toff;
+	char * buf;
+	unsigned char cdhash[SHA1_RESULTLEN];
+	audit_token_t token;
+	unsigned int upid=0, uidversion = 0;
+	
+	forself = error = 0;
+
+	if (pid == 0) 
+		pid = proc_selfpid();
+	if (pid == proc_selfpid())
+		forself = 1;
+
+
+	/* Pre flight checks for CS_OPS_PIDPATH */
+	if (ops == CS_OPS_PIDPATH) {
+		/* usize is unsigned.. */
+	 	if (usize > 4 * PATH_MAX)
+			return(EOVERFLOW);
+		if (kauth_cred_issuser(kauth_cred_get()) != TRUE) 
+			return(EPERM);
+	} else {
+		switch (ops) {
+		case CS_OPS_STATUS:
+		case CS_OPS_CDHASH:
+		case CS_OPS_PIDOFFSET:
+		case CS_OPS_ENTITLEMENTS_BLOB:
+			break;	/* unrestricted */
+		default:
+			if (forself == 0 && kauth_cred_issuser(kauth_cred_get()) != TRUE)
+				return(EPERM);
+			break;
+		}
+	}
+
+	pt = proc_find(pid);
+	if (pt == PROC_NULL)
+		return(ESRCH);
+
+	upid = pt->p_pid;
+	uidversion = pt->p_idversion;
+	if (uaudittoken != USER_ADDR_NULL) {
+		
+		error = copyin(uaudittoken, &token, sizeof(audit_token_t));
+		if (error != 0)
+			goto out;
+		/* verify the audit token pid/idversion matches with proc */
+		if ((token.val[5] != upid) || (token.val[7] != uidversion)) {
+			error = ESRCH;
+			goto out;
+		}
+	}
+
+	switch (ops) {
+
+		case CS_OPS_STATUS:
+			retflags = pt->p_csflags;
+			if (uaddr != USER_ADDR_NULL)
+				error = copyout(&retflags, uaddr, sizeof(uint32_t));
+			break;
+		
+		case CS_OPS_MARKINVALID:
+			proc_lock(pt);
+			if ((pt->p_csflags & CS_VALID) == CS_VALID) {	/* is currently valid */
+				pt->p_csflags &= ~CS_VALID;	/* set invalid */
+				if ((pt->p_csflags & CS_KILL) == CS_KILL) {
+					pt->p_csflags |= CS_KILLED;
+					proc_unlock(pt);
+					if (cs_debug) {
+						printf("CODE SIGNING: marked invalid by pid %d: "
+			       			"p=%d[%s] honoring CS_KILL, final status 0x%x\n",
+			       			proc_selfpid(), pt->p_pid, pt->p_comm, pt->p_csflags);
+					}
+					psignal(pt, SIGKILL);
+				} else
+					proc_unlock(pt);
+			} else
+				proc_unlock(pt);
+				
+			break;
+
+		case CS_OPS_MARKHARD:
+			proc_lock(pt);
+			pt->p_csflags |= CS_HARD;
+			if ((pt->p_csflags & CS_VALID) == 0) {
+				/* @@@ allow? reject? kill? @@@ */
+				proc_unlock(pt);
+				error = EINVAL;
+				goto out;
+			} else
+				proc_unlock(pt);
+			break;
+
+		case CS_OPS_MARKKILL:
+			proc_lock(pt);
+			pt->p_csflags |= CS_KILL;
+			if ((pt->p_csflags & CS_VALID) == 0) {
+				proc_unlock(pt);
+				psignal(pt, SIGKILL);
+			} else
+				proc_unlock(pt);
+			break;
+
+		case CS_OPS_PIDPATH:
+			tvp = pt->p_textvp;
+			vid = vnode_vid(tvp);
+
+			if (tvp == NULLVP) {
+				proc_rele(pt);
+				return(EINVAL);
+			}
+
+			buf = (char *)kalloc(usize);
+			if (buf == NULL)  {
+				proc_rele(pt);
+				return(ENOMEM);
+			}
+			bzero(buf, usize);
+
+			error = vnode_getwithvid(tvp, vid);
+			if (error == 0) {
+				int len; 
+				len = usize;
+				error = vn_getpath(tvp, buf, &len);
+				vnode_put(tvp);
+				if (error == 0) {
+					error = copyout(buf, uaddr, usize);
+				}
+				kfree(buf, usize);
+			}
+
+			proc_rele(pt);
+
+			return(error);
+
+		case CS_OPS_PIDOFFSET:
+			toff = pt->p_textoff;
+			proc_rele(pt);
+			error = copyout(&toff, uaddr, sizeof(toff));
+			return(error);
+
+		case CS_OPS_CDHASH:
+
+			/* pt already holds a reference on its p_textvp */
+			tvp = pt->p_textvp;
+			toff = pt->p_textoff;
+
+			if (tvp == NULLVP || usize != SHA1_RESULTLEN) {
+				proc_rele(pt);
+				return EINVAL;
+			}
+
+			error = vn_getcdhash(tvp, toff, cdhash);
+			proc_rele(pt);
+
+			if (error == 0) {
+				error = copyout(cdhash, uaddr, sizeof (cdhash));
+			}
+
+			return error;
+
+		case CS_OPS_ENTITLEMENTS_BLOB: {
+			char fakeheader[8] = { 0 };
+			void *start;
+			size_t length;
+
+			if ((pt->p_csflags & CS_VALID) == 0) {
+				error = EINVAL;
+				break;
+			}
+			if (usize < sizeof(fakeheader)) {
+				error = ERANGE;
+				break;
+			}
+			if (0 != (error = cs_entitlements_blob_get(pt,
+			    &start, &length)))
+				break;
+			/* if no entitlement, fill in zero header */
+			if (NULL == start) {
+				start = fakeheader;
+				length = sizeof(fakeheader);
+			} else if (usize < length) {
+				/* ... if input too short, copy out length of entitlement */
+				uint32_t length32 = htonl((uint32_t)length);
+				memcpy(&fakeheader[4], &length32, sizeof(length32));
+
+				error = copyout(fakeheader, uaddr, sizeof(fakeheader));
+				if (error == 0)
+					error = ERANGE; /* input buffer to short, ERANGE signals that */
+				break;
+			}
+			error = copyout(start, uaddr, length);
+			break;
+		}
+
+		case CS_OPS_MARKRESTRICT:
+			proc_lock(pt);
+			pt->p_csflags |= CS_RESTRICT;
+			proc_unlock(pt);
+			break;
+
+		default:
+			error = EINVAL;
+			break;
+	}
+out:
+	proc_rele(pt);
+	return(error);
+}
+
+int
+proc_iterate(flags, callout, arg, filterfn, filterarg)
+	int flags;
+	int (*callout)(proc_t, void *);
+	void * arg;
+	int (*filterfn)(proc_t, void *);
+	void * filterarg;
+{
+	proc_t p;
+	pid_t * pid_list;
+	int count, pidcount, alloc_count, i, retval;
+
+	count = nprocs+ 10;
+	if (count > hard_maxproc)
+		count = hard_maxproc;
+	alloc_count = count * sizeof(pid_t);
+	pid_list = (pid_t *)kalloc(alloc_count);
+	bzero(pid_list, alloc_count);
+
+
+	proc_list_lock();
+
+
+	pidcount = 0;
+	if (flags & PROC_ALLPROCLIST) {
+		for (p = allproc.lh_first; (p != 0); p = p->p_list.le_next) {
+			if (p->p_stat == SIDL)
+				continue;
+			if ( (filterfn == 0 ) || (filterfn(p, filterarg) != 0)) {
+				pid_list[pidcount] = p->p_pid;
+				pidcount++;
+				if (pidcount >= count)
+					break;
+			}
+		}
+	}
+	if ((pidcount <  count ) && (flags & PROC_ZOMBPROCLIST)) {
+		for (p = zombproc.lh_first; p != 0; p = p->p_list.le_next) {
+			if ( (filterfn == 0 ) || (filterfn(p, filterarg) != 0)) {
+				pid_list[pidcount] = p->p_pid;
+				pidcount++;
+				if (pidcount >= count)
+					break;
+			}
+		}
+	}
+		
+
+	proc_list_unlock();
+
+
+	for (i = 0; i< pidcount; i++) {
+		p = proc_find(pid_list[i]);
+		if (p) {
+			if ((flags & PROC_NOWAITTRANS) == 0)
+				proc_transwait(p, 0);
+			retval = callout(p, arg);
+
+			switch (retval) {
+		  		case PROC_RETURNED:
+		  		case PROC_RETURNED_DONE:
+			  		proc_rele(p);
+			  		if (retval == PROC_RETURNED_DONE) {
+						goto out;
+			  		}
+			  		break;
+
+		  		case PROC_CLAIMED_DONE:
+					goto out;
+		  		case PROC_CLAIMED:
+		  		default:
+					break;
+			}
+		} else if (flags & PROC_ZOMBPROCLIST) {
+			p = proc_find_zombref(pid_list[i]);
+			if (p != PROC_NULL) {
+				retval = callout(p, arg);
+		
+				switch (retval) {
+		  			case PROC_RETURNED:
+		  			case PROC_RETURNED_DONE:
+						proc_drop_zombref(p);
+			  			if (retval == PROC_RETURNED_DONE) {
+							goto out;
+			  			}
+			  			break;
+
+		  			case PROC_CLAIMED_DONE:
+						goto out;
+		  			case PROC_CLAIMED:
+		  			default:
+						break;
+				}
+			}
+		}
+	}
+
+out: 
+	kfree(pid_list, alloc_count);
+	return(0);
+
+}
+
+
+#if 0
+/* This is for iteration in case of trivial non blocking callouts */
+int
+proc_scanall(flags, callout, arg)
+	int flags;
+	int (*callout)(proc_t, void *);
+	void * arg;
+{
+	proc_t p;
+	int retval;
+
+
+	proc_list_lock();
+
+
+	if (flags & PROC_ALLPROCLIST) {
+		for (p = allproc.lh_first; (p != 0); p = p->p_list.le_next) {
+			retval = callout(p, arg);
+			if (retval == PROC_RETURNED_DONE)
+				goto out;
+		}
+	}
+	if (flags & PROC_ZOMBPROCLIST) {
+		for (p = zombproc.lh_first; p != 0; p = p->p_list.le_next) {
+			retval = callout(p, arg);
+			if (retval == PROC_RETURNED_DONE)
+				goto out;
+		}
+	}
+out:
+
+	proc_list_unlock();
+
+	return(0);
+}
+#endif
+
+
+int
+proc_rebootscan(callout, arg, filterfn, filterarg)
+	int (*callout)(proc_t, void *);
+	void * arg;
+	int (*filterfn)(proc_t, void *);
+	void * filterarg;
+{
+	proc_t p;
+	int lockheld = 0, retval;
+
+	proc_shutdown_exitcount = 0;
+
+ps_allprocscan:
+
+	proc_list_lock();
+
+	lockheld = 1;
+
+	for (p = allproc.lh_first; (p != 0); p = p->p_list.le_next) {
+		if ( (filterfn == 0 ) || (filterfn(p, filterarg) != 0)) {
+			p = proc_ref_locked(p);
+
+			proc_list_unlock();
+			lockheld = 0;
+
+			if (p) {
+				proc_transwait(p, 0);
+				retval = callout(p, arg);
+				proc_rele(p);
+	
+				switch (retval) {
+					case PROC_RETURNED_DONE:
+					case PROC_CLAIMED_DONE:
+						goto out;
+				}
+			}
+			goto ps_allprocscan;	
+		} /* filter pass */
+	} /* allproc walk thru */
+
+	if (lockheld == 1) {
+		proc_list_unlock();
+		lockheld = 0;
+	}
+
+out: 
+	return(0);
+
+}
+
+
+int
+proc_childrenwalk(parent, callout, arg)
+	struct proc * parent;
+	int (*callout)(proc_t, void *);
+	void * arg;
+{
+	register struct proc *p;
+	pid_t * pid_list;
+	int count, pidcount, alloc_count, i, retval;
+
+	count = nprocs+ 10;
+	if (count > hard_maxproc)
+		count = hard_maxproc;
+	alloc_count = count * sizeof(pid_t);
+	pid_list = (pid_t *)kalloc(alloc_count);
+	bzero(pid_list, alloc_count);
+
+
+	proc_list_lock();
+
+
+	pidcount = 0;
+	for (p = parent->p_children.lh_first; (p != 0); p = p->p_sibling.le_next) {
+		if (p->p_stat == SIDL)
+			continue;
+		pid_list[pidcount] = p->p_pid;
+		pidcount++;
+		if (pidcount >= count)
+			break;
+	}
+	proc_list_unlock();
+
+
+	for (i = 0; i< pidcount; i++) {
+		p = proc_find(pid_list[i]);
+		if (p) {
+			proc_transwait(p, 0);
+			retval = callout(p, arg);
+
+			switch (retval) {
+		  		case PROC_RETURNED:
+		  		case PROC_RETURNED_DONE:
+			  		proc_rele(p);
+			  		if (retval == PROC_RETURNED_DONE) {
+						goto out;
+			  		}
+			  		break;
+
+		  		case PROC_CLAIMED_DONE:
+					goto out;
+		  		case PROC_CLAIMED:
+		  		default:
+					break;
+			}
+		}
+	}
+
+out: 
+	kfree(pid_list, alloc_count);
+	return(0);
+
+}
+
+/*
+ */
+/* PGRP_BLOCKITERATE is not implemented yet */
+int
+pgrp_iterate(pgrp, flags, callout, arg, filterfn, filterarg)
+	struct pgrp *pgrp;
+	int flags;
+	int (*callout)(proc_t, void *);
+	void * arg;
+	int (*filterfn)(proc_t, void *);
+	void * filterarg;
+{
+	proc_t p;
+	pid_t * pid_list;
+	int count, pidcount, i, alloc_count;
+	int retval;
+	pid_t pgid;
+	int dropref = flags & PGRP_DROPREF;
+#if 0
+	int serialize = flags & PGRP_BLOCKITERATE;
+#else
+	int serialize = 0;
+#endif
+
+	if (pgrp == 0)
+		return(0);
+	count = pgrp->pg_membercnt + 10;
+	if (count > hard_maxproc)
+		count = hard_maxproc;
+	alloc_count = count * sizeof(pid_t);
+	pid_list = (pid_t *)kalloc(alloc_count);
+	bzero(pid_list, alloc_count);
+	
+	pgrp_lock(pgrp);
+	if (serialize  != 0) {
+		while ((pgrp->pg_listflags & PGRP_FLAG_ITERABEGIN) == PGRP_FLAG_ITERABEGIN) {
+			pgrp->pg_listflags |= PGRP_FLAG_ITERWAIT;
+			msleep(&pgrp->pg_listflags, &pgrp->pg_mlock, 0, "pgrp_iterate", 0);
+		}
+		pgrp->pg_listflags |= PGRP_FLAG_ITERABEGIN;
+	}
+
+	pgid = pgrp->pg_id;
+
+	pidcount = 0;
+	for (p = pgrp->pg_members.lh_first; p != 0;
+	     p = p->p_pglist.le_next) {
+		if ( (filterfn == 0 ) || (filterfn(p, filterarg) != 0)) {
+			pid_list[pidcount] = p->p_pid;
+			pidcount++;
+			if (pidcount >= count)
+				break;
+		}
+	}
+		
+
+	pgrp_unlock(pgrp);
+	if ((serialize == 0) && (dropref != 0))
+		pg_rele(pgrp);
+
+
+	for (i = 0; i< pidcount; i++) {
+		/* No handling or proc0 */
+		if (pid_list[i] == 0)
+			continue;
+		p = proc_find(pid_list[i]);
+		if (p) {
+			if (p->p_pgrpid != pgid) {
+				proc_rele(p);
+				continue;
+			}
+			proc_transwait(p, 0);
+			retval = callout(p, arg);
+
+			switch (retval) {
+		  		case PROC_RETURNED:
+		  		case PROC_RETURNED_DONE:
+			  		proc_rele(p);
+			  		if (retval == PROC_RETURNED_DONE) {
+						goto out;
+			  		}
+			  		break;
+
+		  		case PROC_CLAIMED_DONE:
+					goto out;
+		  		case PROC_CLAIMED:
+		  		default:
+					break;
+			}
+		}
+	}
+out:
+	if (serialize != 0) {
+		pgrp_lock(pgrp);
+		pgrp->pg_listflags &= ~PGRP_FLAG_ITERABEGIN;
+		if ((pgrp->pg_listflags & PGRP_FLAG_ITERWAIT) == PGRP_FLAG_ITERWAIT) {
+			pgrp->pg_listflags &= ~PGRP_FLAG_ITERWAIT;
+			wakeup(&pgrp->pg_listflags);
+		}
+		pgrp_unlock(pgrp);
+		if (dropref != 0)
+			pg_rele(pgrp);
+	}
+	kfree(pid_list, alloc_count);
+	return(0);
+}
+
+static void
+pgrp_add(struct pgrp * pgrp, struct proc * parent, struct proc * child)
+{
+	proc_list_lock();
+	child->p_pgrp = pgrp;
+	child->p_pgrpid = pgrp->pg_id;
+	child->p_listflag |= P_LIST_INPGRP;
+	/*
+	 * When pgrp is being freed , a process can still 
+	 * request addition using setpgid from bash when 
+ 	 * login is terminated (login cycler) return ESRCH
+	 * Safe to hold lock due to refcount on pgrp 
+	 */
+	if ((pgrp->pg_listflags & (PGRP_FLAG_TERMINATE | PGRP_FLAG_DEAD)) == PGRP_FLAG_TERMINATE) {
+		pgrp->pg_listflags &= ~PGRP_FLAG_TERMINATE;	
+	}
+
+	if ((pgrp->pg_listflags & PGRP_FLAG_DEAD) == PGRP_FLAG_DEAD)
+		panic("pgrp_add : pgrp is dead adding process");
+	proc_list_unlock();
+
+	pgrp_lock(pgrp);
+	pgrp->pg_membercnt++;
+	if ( parent != PROC_NULL) {
+		LIST_INSERT_AFTER(parent, child, p_pglist);
+	 }else {
+		LIST_INSERT_HEAD(&pgrp->pg_members, child, p_pglist);
+	}
+	pgrp_unlock(pgrp);
+
+	proc_list_lock();
+	if (((pgrp->pg_listflags & (PGRP_FLAG_TERMINATE | PGRP_FLAG_DEAD)) == PGRP_FLAG_TERMINATE) && (pgrp->pg_membercnt != 0)) {
+		pgrp->pg_listflags &= ~PGRP_FLAG_TERMINATE;	
+	}
+	proc_list_unlock();
+}
+
+static void
+pgrp_remove(struct proc * p)
+{
+	struct pgrp * pg;
+
+	pg = proc_pgrp(p);
+
+	proc_list_lock();
+#if __PROC_INTERNAL_DEBUG
+	if ((p->p_listflag & P_LIST_INPGRP) == 0)
+		panic("removing from pglist but no named ref\n");
+#endif
+	p->p_pgrpid = PGRPID_DEAD;
+	p->p_listflag &= ~P_LIST_INPGRP;
+	p->p_pgrp = NULL;
+	proc_list_unlock();
+
+	if (pg == PGRP_NULL)
+		panic("pgrp_remove: pg is NULL");
+	pgrp_lock(pg);
+	pg->pg_membercnt--;
+
+	if (pg->pg_membercnt < 0)
+		panic("pgprp: -ve membercnt pgprp:%p p:%p\n",pg, p);
+
+	LIST_REMOVE(p, p_pglist);
+	if (pg->pg_members.lh_first == 0) {
+		pgrp_unlock(pg);
+		pgdelete_dropref(pg);
+	} else {
+		pgrp_unlock(pg);
+		pg_rele(pg);
+	}
+}
+
+
+/* cannot use proc_pgrp as it maybe stalled */
+static void
+pgrp_replace(struct proc * p, struct pgrp * newpg)
+{
+        struct pgrp * oldpg;
+
+
+
+       proc_list_lock();
+
+	while ((p->p_listflag & P_LIST_PGRPTRANS) == P_LIST_PGRPTRANS) {
+		p->p_listflag |= P_LIST_PGRPTRWAIT;
+		(void)msleep(&p->p_pgrpid, proc_list_mlock, 0, "proc_pgrp", 0);
+	}
+
+	p->p_listflag |= P_LIST_PGRPTRANS;
+
+	oldpg = p->p_pgrp;
+	if (oldpg == PGRP_NULL)
+		panic("pgrp_replace: oldpg NULL");
+	oldpg->pg_refcount++;
+#if __PROC_INTERNAL_DEBUG
+        if ((p->p_listflag & P_LIST_INPGRP) == 0)
+                panic("removing from pglist but no named ref\n");
+#endif
+        p->p_pgrpid = PGRPID_DEAD;
+        p->p_listflag &= ~P_LIST_INPGRP;
+        p->p_pgrp = NULL;
+ 
+       proc_list_unlock();
+
+       pgrp_lock(oldpg);
+       oldpg->pg_membercnt--;
+       if (oldpg->pg_membercnt < 0)
+                panic("pgprp: -ve membercnt pgprp:%p p:%p\n",oldpg, p);
+       LIST_REMOVE(p, p_pglist);
+        if (oldpg->pg_members.lh_first == 0) {
+                pgrp_unlock(oldpg);
+                pgdelete_dropref(oldpg);
+        } else {
+                pgrp_unlock(oldpg);
+                pg_rele(oldpg);
+        }
+
+        proc_list_lock();
+        p->p_pgrp = newpg;
+        p->p_pgrpid = newpg->pg_id;
+        p->p_listflag |= P_LIST_INPGRP;
+        /*
+         * When pgrp is being freed , a process can still
+         * request addition using setpgid from bash when 
+         * login is terminated (login cycler) return ESRCH
+         * Safe to hold lock due to refcount on pgrp 
+         */
+        if ((newpg->pg_listflags & (PGRP_FLAG_TERMINATE | PGRP_FLAG_DEAD)) == PGRP_FLAG_TERMINATE) {
+                newpg->pg_listflags &= ~PGRP_FLAG_TERMINATE;
+        }
+
+        if ((newpg->pg_listflags & PGRP_FLAG_DEAD) == PGRP_FLAG_DEAD)
+                panic("pgrp_add : pgrp is dead adding process");
+        proc_list_unlock();
+
+        pgrp_lock(newpg);
+        newpg->pg_membercnt++;
+	LIST_INSERT_HEAD(&newpg->pg_members, p, p_pglist);
+        pgrp_unlock(newpg);
+
+        proc_list_lock();
+        if (((newpg->pg_listflags & (PGRP_FLAG_TERMINATE | PGRP_FLAG_DEAD)) == PGRP_FLAG_TERMINATE) && (newpg->pg_membercnt != 0)) {
+                newpg->pg_listflags &= ~PGRP_FLAG_TERMINATE;
+        }
+
+	p->p_listflag &= ~P_LIST_PGRPTRANS;
+	if ((p->p_listflag & P_LIST_PGRPTRWAIT) == P_LIST_PGRPTRWAIT) {
+		p->p_listflag &= ~P_LIST_PGRPTRWAIT;
+		wakeup(&p->p_pgrpid);
+		
+	}
+        proc_list_unlock();
+}
+
+void
+pgrp_lock(struct pgrp * pgrp)
+{
+	lck_mtx_lock(&pgrp->pg_mlock);
+}
+
+void
+pgrp_unlock(struct pgrp * pgrp)
+{
+	lck_mtx_unlock(&pgrp->pg_mlock);
+}
+
+void
+session_lock(struct session * sess)
+{
+	lck_mtx_lock(&sess->s_mlock);
+}
+
+
+void
+session_unlock(struct session * sess)
+{
+	lck_mtx_unlock(&sess->s_mlock);
+}
+
+struct pgrp *
+proc_pgrp(proc_t p)
+{
+	struct pgrp * pgrp;
+
+	if (p == PROC_NULL)
+		return(PGRP_NULL);
+	proc_list_lock();
+
+	while ((p->p_listflag & P_LIST_PGRPTRANS) == P_LIST_PGRPTRANS) {
+		p->p_listflag |= P_LIST_PGRPTRWAIT;
+		(void)msleep(&p->p_pgrpid, proc_list_mlock, 0, "proc_pgrp", 0);
+	}
+		
+	pgrp = p->p_pgrp;
+
+	assert(pgrp != NULL);
+
+	if (pgrp != PGRP_NULL) {
+		pgrp->pg_refcount++;
+		if ((pgrp->pg_listflags & (PGRP_FLAG_TERMINATE | PGRP_FLAG_DEAD)) != 0)
+			panic("proc_pgrp: ref being povided for dead pgrp");
+	}
+		
+	proc_list_unlock();
+	
+	return(pgrp);
+}
+
+struct pgrp *
+tty_pgrp(struct tty * tp)
+{
+	struct pgrp * pg = PGRP_NULL;
+
+	proc_list_lock();
+	pg = tp->t_pgrp;
+
+	if (pg != PGRP_NULL) {
+		if ((pg->pg_listflags & PGRP_FLAG_DEAD) != 0)
+			panic("tty_pgrp: ref being povided for dead pgrp");
+		pg->pg_refcount++;
+	}
+	proc_list_unlock();
+
+	return(pg);
+}
+
+struct session *
+proc_session(proc_t p)
+{
+	struct session * sess = SESSION_NULL;
+	
+	if (p == PROC_NULL)
+		return(SESSION_NULL);
+
+	proc_list_lock();
+
+	/* wait during transitions */
+	while ((p->p_listflag & P_LIST_PGRPTRANS) == P_LIST_PGRPTRANS) {
+		p->p_listflag |= P_LIST_PGRPTRWAIT;
+		(void)msleep(&p->p_pgrpid, proc_list_mlock, 0, "proc_pgrp", 0);
+	}
+
+	if ((p->p_pgrp != PGRP_NULL) && ((sess = p->p_pgrp->pg_session) != SESSION_NULL)) {
+		if ((sess->s_listflags & (S_LIST_TERM | S_LIST_DEAD)) != 0)
+			panic("proc_session:returning sesssion ref on terminating session");
+		sess->s_count++;
+	}
+	proc_list_unlock();
+	return(sess);
+}
+
+void
+session_rele(struct session *sess)
+{
+	proc_list_lock();
+	if (--sess->s_count == 0) {
+		if ((sess->s_listflags & (S_LIST_TERM | S_LIST_DEAD)) != 0)
+			panic("session_rele: terminating already terminated session");
+		sess->s_listflags |= S_LIST_TERM;
+		LIST_REMOVE(sess, s_hash);
+		sess->s_listflags |= S_LIST_DEAD;
+		if (sess->s_count != 0)
+			panic("session_rele: freeing session in use");	
+		proc_list_unlock();
+#if CONFIG_FINE_LOCK_GROUPS
+		lck_mtx_destroy(&sess->s_mlock, proc_mlock_grp);
+#else
+		lck_mtx_destroy(&sess->s_mlock, proc_lck_grp);
+#endif
+		FREE_ZONE(sess, sizeof(struct session), M_SESSION);
+	} else
+		proc_list_unlock();
+}
+
+int
+proc_transstart(proc_t p, int locked)
+{
+	if (locked == 0)
+		proc_lock(p);
+	while ((p->p_lflag & P_LINTRANSIT) == P_LINTRANSIT) {
+		if ((p->p_lflag & P_LTRANSCOMMIT) == P_LTRANSCOMMIT) {
+			if (locked == 0)
+				proc_unlock(p);
+			return EDEADLK;
+		}
+		p->p_lflag |= P_LTRANSWAIT;
+		msleep(&p->p_lflag, &p->p_mlock, 0, "proc_signstart", NULL);
+	}
+	p->p_lflag |= P_LINTRANSIT;
+	p->p_transholder = current_thread();
+	if (locked == 0)
+		proc_unlock(p);
+	return 0;
+}
+
+void
+proc_transcommit(proc_t p, int locked)
+{
+	if (locked == 0)
+		proc_lock(p);
+
+	assert ((p->p_lflag & P_LINTRANSIT) == P_LINTRANSIT);
+	assert (p->p_transholder == current_thread());
+	p->p_lflag |= P_LTRANSCOMMIT;
+
+	if ((p->p_lflag & P_LTRANSWAIT) == P_LTRANSWAIT) {
+		p->p_lflag &= ~P_LTRANSWAIT;
+		wakeup(&p->p_lflag);
+	}
+	if (locked == 0)
+		proc_unlock(p);
+}
+
+void
+proc_transend(proc_t p, int locked)
+{
+	if (locked == 0)
+		proc_lock(p);
+
+	p->p_lflag &= ~( P_LINTRANSIT | P_LTRANSCOMMIT);
+	p->p_transholder = NULL;
+
+	if ((p->p_lflag & P_LTRANSWAIT) == P_LTRANSWAIT) {
+		p->p_lflag &= ~P_LTRANSWAIT;
+		wakeup(&p->p_lflag);
+	}
+	if (locked == 0)
+		proc_unlock(p);
+}
+
+int
+proc_transwait(proc_t p, int locked)
+{
+	if (locked == 0)
+		proc_lock(p);
+	while ((p->p_lflag & P_LINTRANSIT) == P_LINTRANSIT) {
+		if ((p->p_lflag & P_LTRANSCOMMIT) == P_LTRANSCOMMIT && current_proc() == p) {
+			if (locked == 0)
+				proc_unlock(p);
+			return EDEADLK;
+		}
+		p->p_lflag |= P_LTRANSWAIT;
+		msleep(&p->p_lflag, &p->p_mlock, 0, "proc_signstart", NULL);
+	}
+	if (locked == 0)
+		proc_unlock(p);
+	return 0;
+}
+
+void
+proc_klist_lock(void)
+{
+	lck_mtx_lock(proc_klist_mlock);
+}
+
+void
+proc_klist_unlock(void)
+{
+	lck_mtx_unlock(proc_klist_mlock);
+}
+
+void
+proc_knote(struct proc * p, long hint)
+{
+	proc_klist_lock();
+	KNOTE(&p->p_klist, hint);
+	proc_klist_unlock();
+}
+
+void
+proc_knote_drain(struct proc *p)
+{
+	struct knote *kn = NULL;
+
+	/*
+	 * Clear the proc's klist to avoid references after the proc is reaped.
+	 */
+	proc_klist_lock();
+	while ((kn = SLIST_FIRST(&p->p_klist))) {
+		kn->kn_ptr.p_proc = PROC_NULL;
+		KNOTE_DETACH(&p->p_klist, kn);
+	}
+	proc_klist_unlock();
+}
+
+unsigned long cs_procs_killed = 0;
+unsigned long cs_procs_invalidated = 0;
+int cs_force_kill = 0;
+int cs_force_hard = 0;
+int cs_debug = 0;
+SYSCTL_INT(_vm, OID_AUTO, cs_force_kill, CTLFLAG_RW | CTLFLAG_LOCKED, &cs_force_kill, 0, "");
+SYSCTL_INT(_vm, OID_AUTO, cs_force_hard, CTLFLAG_RW | CTLFLAG_LOCKED, &cs_force_hard, 0, "");
+SYSCTL_INT(_vm, OID_AUTO, cs_debug, CTLFLAG_RW | CTLFLAG_LOCKED, &cs_debug, 0, "");
+
+int
+cs_allow_invalid(struct proc *p)
+{
+#if MACH_ASSERT
+	lck_mtx_assert(&p->p_mlock, LCK_MTX_ASSERT_NOTOWNED);
+#endif
+#if CONFIG_MACF && CONFIG_ENFORCE_SIGNED_CODE
+	/* There needs to be a MAC policy to implement this hook, or else the
+	 * kill bits will be cleared here every time. If we have 
+	 * CONFIG_ENFORCE_SIGNED_CODE, we can assume there is a policy
+	 * implementing the hook. 
+	 */
+	if( 0 != mac_proc_check_run_cs_invalid(p)) {
+		if(cs_debug) printf("CODE SIGNING: cs_allow_invalid() "
+				    "not allowed: pid %d\n", 
+				    p->p_pid);
+		return 0;
+	}
+	if(cs_debug) printf("CODE SIGNING: cs_allow_invalid() "
+			    "allowed: pid %d\n", 
+			    p->p_pid);
+	proc_lock(p);
+	p->p_csflags &= ~(CS_KILL | CS_HARD | CS_VALID);
+	proc_unlock(p);
+	vm_map_switch_protect(get_task_map(p->task), FALSE);
+#endif
+	return (p->p_csflags & (CS_KILL | CS_HARD)) == 0;
+}
+
+int
+cs_invalid_page(
+	addr64_t vaddr)
+{
+	struct proc	*p;
+	int		retval;
+
+	p = current_proc();
+
+	/*
+	 * XXX revisit locking when proc is no longer protected
+	 * by the kernel funnel...
+	 */
+
+	/* XXX for testing */
+	proc_lock(p);
+	if (cs_force_kill)
+		p->p_csflags |= CS_KILL;
+	if (cs_force_hard)
+		p->p_csflags |= CS_HARD;
+
+	/* CS_KILL triggers us to send a kill signal. Nothing else. */
+	if (p->p_csflags & CS_KILL) {
+		p->p_csflags |= CS_KILLED;
+		proc_unlock(p);
+		if (cs_debug) {
+			printf("CODE SIGNING: cs_invalid_page(0x%llx): "
+			       "p=%d[%s] honoring CS_KILL, final status 0x%x\n",
+			       vaddr, p->p_pid, p->p_comm, p->p_csflags);
+		}
+		cs_procs_killed++;
+		psignal(p, SIGKILL);
+		proc_lock(p);
+	}
+	
+	/* CS_HARD means fail the mapping operation so the process stays valid. */
+	if (p->p_csflags & CS_HARD) {
+		proc_unlock(p);
+		if (cs_debug) {
+			printf("CODE SIGNING: cs_invalid_page(0x%llx): "
+			       "p=%d[%s] honoring CS_HARD\n",
+			       vaddr, p->p_pid, p->p_comm);
+		}
+		retval = 1;
+	} else {
+		if (p->p_csflags & CS_VALID) {
+			p->p_csflags &= ~CS_VALID;
+			
+			proc_unlock(p);
+			cs_procs_invalidated++;
+			printf("CODE SIGNING: cs_invalid_page(0x%llx): "
+			       "p=%d[%s] clearing CS_VALID\n",
+			       vaddr, p->p_pid, p->p_comm);
+		} else {
+			proc_unlock(p);
+		}
+		
+		retval = 0;
+	}
+
+	return retval;
+}
+
+void 
+proc_setregister(proc_t p)
+{
+	proc_lock(p);
+	p->p_lflag |= P_LREGISTER;
+	proc_unlock(p);
+}
+
+void 
+proc_resetregister(proc_t p)
+{
+	proc_lock(p);
+	p->p_lflag &= ~P_LREGISTER;
+	proc_unlock(p);
+}
+
+pid_t
+proc_pgrpid(proc_t p)
+{
+	return p->p_pgrpid;
+}
+
+pid_t
+proc_selfpgrpid()
+{
+	return current_proc()->p_pgrpid;
+}
+
+
+/* return control and action states */
+int
+proc_getpcontrol(int pid, int * pcontrolp)
+{
+	proc_t p;
+
+	p = proc_find(pid);
+	if (p == PROC_NULL)
+		return(ESRCH);
+	if (pcontrolp != NULL)
+		*pcontrolp = p->p_pcaction;
+
+	proc_rele(p);
+	return(0);
+}
+
+int
+proc_dopcontrol(proc_t p, void *num_found)
+{
+	int pcontrol;
+
+	proc_lock(p);
+
+	pcontrol = PROC_CONTROL_STATE(p);
+
+	if (PROC_ACTION_STATE(p) ==0) {
+		switch(pcontrol) {
+			case P_PCTHROTTLE:
+				PROC_SETACTION_STATE(p);
+				proc_unlock(p);
+				printf("low swap: throttling pid %d (%s)\n", p->p_pid, p->p_comm);
+				(*(int *)num_found)++;
+				break;
+
+			case P_PCSUSP:
+				PROC_SETACTION_STATE(p);
+				proc_unlock(p);
+				printf("low swap: suspending pid %d (%s)\n", p->p_pid, p->p_comm);
+				task_suspend(p->task);
+				(*(int *)num_found)++;
+				break;
+
+			case P_PCKILL:
+				PROC_SETACTION_STATE(p);
+				proc_unlock(p);
+				printf("low swap: killing pid %d (%s)\n", p->p_pid, p->p_comm);
+				psignal(p, SIGKILL);
+				(*(int *)num_found)++;
+				break;
+
+			default:
+				proc_unlock(p);
+		}
+
+	} else 
+		proc_unlock(p);
+
+	return(PROC_RETURNED);
+}
+
+
+/*
+ * Resume a throttled or suspended process.  This is an internal interface that's only
+ * used by the user level code that presents the GUI when we run out of swap space and 
+ * hence is restricted to processes with superuser privileges.
+ */
+
+int
+proc_resetpcontrol(int pid)
+{
+	proc_t p;
+	int pcontrol;
+	int error;
+	proc_t self = current_proc();
+
+	/* if the process has been validated to handle resource control or root is valid one */
+	if (((self->p_lflag & P_LVMRSRCOWNER) == 0) && (error = suser(kauth_cred_get(), 0)))
+		return error;
+
+	p = proc_find(pid);
+	if (p == PROC_NULL)
+		return(ESRCH);
+	
+	proc_lock(p);
+
+	pcontrol = PROC_CONTROL_STATE(p);
+
+	if(PROC_ACTION_STATE(p) !=0) {
+		switch(pcontrol) {
+			case P_PCTHROTTLE:
+				PROC_RESETACTION_STATE(p);
+				proc_unlock(p);
+				printf("low swap: unthrottling pid %d (%s)\n", p->p_pid, p->p_comm);
+				break;
+
+			case P_PCSUSP:
+				PROC_RESETACTION_STATE(p);
+				proc_unlock(p);
+				printf("low swap: resuming pid %d (%s)\n", p->p_pid, p->p_comm);
+				task_resume(p->task);
+				break;
+
+			case P_PCKILL:
+				/* Huh? */
+				PROC_SETACTION_STATE(p);
+				proc_unlock(p);
+				printf("low swap: attempt to unkill pid %d (%s) ignored\n", p->p_pid, p->p_comm);
+				break;
+
+			default:
+				proc_unlock(p);
+		}
+
+	} else 
+		proc_unlock(p);
+
+	proc_rele(p);
+	return(0);
+}
+
+
+/*
+ * Return true if the specified process has an action state specified for it and it isn't
+ * already in an action state and it's using more physical memory than the specified threshold.
+ * Note: the memory_threshold argument is specified in bytes and is of type uint64_t.
+ */
+
+static int
+proc_pcontrol_filter(proc_t p, void *memory_thresholdp)
+{
+	
+	return PROC_CONTROL_STATE(p) && 						/* if there's an action state specified... */
+	      (PROC_ACTION_STATE(p) == 0) && 						/* and we're not in the action state yet... */
+	      (get_task_resident_size(p->task) > *((uint64_t *)memory_thresholdp)); 	/* and this proc is over the mem threshold, */
+											/* then return true to take action on this proc */
+}
+
+
+
+/*
+ * Deal with the out of swap space condition.  This routine gets called when
+ * we want to swap something out but there's no more space left.  Since this
+ * creates a memory deadlock situtation, we need to take action to free up
+ * some memory resources in order to prevent the system from hanging completely.
+ * The action we take is based on what the system processes running at user level
+ * have specified.  Processes are marked in one of four categories: ones that
+ * can be killed immediately, ones that should be suspended, ones that should
+ * be throttled, and all the rest which are basically none of the above.  Which
+ * processes are marked as being in which category is a user level policy decision;
+ * we just take action based on those decisions here.
+ */
+
+#define STARTING_PERCENTAGE	50	/* memory threshold expressed as a percentage */
+					/* of physical memory			      */
+
+struct timeval	last_no_space_action = {0, 0};
+
+void
+no_paging_space_action(void)
+{
+
+	uint64_t	memory_threshold;
+	int		num_found;
+	struct timeval	now;
+
+	/*
+	 * Throttle how often we come through here.  Once every 20 seconds should be plenty.
+	 */
+
+	microtime(&now);
+
+	if (now.tv_sec <= last_no_space_action.tv_sec + 20)
+		return;
+
+	last_no_space_action = now;
+
+	/*
+	 * Examine all processes and find those that have been marked to have some action
+	 * taken when swap space runs out.  Of those processes, select one or more and 
+	 * apply the specified action to them.  The idea is to only take action against
+	 * a few processes rather than hitting too many at once.  If the low swap condition
+	 * persists, this routine will get called again and we'll take action against more
+	 * processes.
+	 *
+	 * Of the processes that have been marked, we choose which ones to take action 
+	 * against according to how much physical memory they're presently using.  We
+	 * start with the STARTING_THRESHOLD and any processes using more physical memory
+	 * than the percentage threshold will have action taken against it.  If there
+	 * are no processes over the threshold, then the threshold is cut in half and we
+	 * look again for processes using more than this threshold.  We continue in
+	 * this fashion until we find at least one process to take action against.  This
+	 * iterative approach is less than ideally efficient, however we only get here
+	 * when the system is almost in a memory deadlock and is pretty much just
+	 * thrashing if it's doing anything at all.  Therefore, the cpu overhead of
+	 * potentially multiple passes here probably isn't revelant.
+	 */
+
+	memory_threshold = (sane_size * STARTING_PERCENTAGE) / 100;	/* resident threshold in bytes */
+
+	for (num_found = 0; num_found == 0; memory_threshold = memory_threshold / 2) {
+		proc_iterate(PROC_ALLPROCLIST, proc_dopcontrol, (void *)&num_found, proc_pcontrol_filter, (void *)&memory_threshold);
+
+		/*
+		 * If we just looked with memory_threshold == 0, then there's no need to iterate any further since
+		 * we won't find any eligible processes at this point.
+		 */
+
+		if (memory_threshold == 0) {
+			if (num_found == 0)	/* log that we couldn't do anything in this case */
+				printf("low swap: unable to find any eligible processes to take action on\n");
+
+			break;
+		}
+	}
 }