17c478bd9Sstevel@tonic-gate /*
27c478bd9Sstevel@tonic-gate  * CDDL HEADER START
37c478bd9Sstevel@tonic-gate  *
47c478bd9Sstevel@tonic-gate  * The contents of this file are subject to the terms of the
5*7257d1b4Sraf  * Common Development and Distribution License (the "License").
6*7257d1b4Sraf  * You may not use this file except in compliance with the License.
77c478bd9Sstevel@tonic-gate  *
87c478bd9Sstevel@tonic-gate  * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
97c478bd9Sstevel@tonic-gate  * or http://www.opensolaris.org/os/licensing.
107c478bd9Sstevel@tonic-gate  * See the License for the specific language governing permissions
117c478bd9Sstevel@tonic-gate  * and limitations under the License.
127c478bd9Sstevel@tonic-gate  *
137c478bd9Sstevel@tonic-gate  * When distributing Covered Code, include this CDDL HEADER in each
147c478bd9Sstevel@tonic-gate  * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
157c478bd9Sstevel@tonic-gate  * If applicable, add the following below this CDDL HEADER, with the
167c478bd9Sstevel@tonic-gate  * fields enclosed by brackets "[]" replaced with your own identifying
177c478bd9Sstevel@tonic-gate  * information: Portions Copyright [yyyy] [name of copyright owner]
187c478bd9Sstevel@tonic-gate  *
197c478bd9Sstevel@tonic-gate  * CDDL HEADER END
207c478bd9Sstevel@tonic-gate  */
21*7257d1b4Sraf 
227c478bd9Sstevel@tonic-gate /*
23*7257d1b4Sraf  * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
247c478bd9Sstevel@tonic-gate  * Use is subject to license terms.
257c478bd9Sstevel@tonic-gate  */
267c478bd9Sstevel@tonic-gate 
277c478bd9Sstevel@tonic-gate #pragma ident	"%Z%%M%	%I%	%E% SMI"
287c478bd9Sstevel@tonic-gate 
29*7257d1b4Sraf #include "lint.h"
307c478bd9Sstevel@tonic-gate #include "thr_uberdata.h"
317c478bd9Sstevel@tonic-gate #include "stack_unwind.h"
327c478bd9Sstevel@tonic-gate #include "reg_num.h"
337c478bd9Sstevel@tonic-gate #include <dlfcn.h>
347c478bd9Sstevel@tonic-gate 
357c478bd9Sstevel@tonic-gate /*
367c478bd9Sstevel@tonic-gate  * Due to the subtle mysteries of the amd64 unwind interfaces, the
377c478bd9Sstevel@tonic-gate  * "Canonical Frame Address" is 16 bytes higher in memory than the
387c478bd9Sstevel@tonic-gate  * value of the frame pointer (%fp).
397c478bd9Sstevel@tonic-gate  */
407c478bd9Sstevel@tonic-gate #define	CFA_ADJUST	16
417c478bd9Sstevel@tonic-gate 
427c478bd9Sstevel@tonic-gate /* ARGSUSED */
437c478bd9Sstevel@tonic-gate static _Unwind_Reason_Code
posix_stop_func(int version,_Unwind_Action _Unwind_actions,uint64_t exceptionClass,struct _Unwind_Exception * exceptionObject,struct _Unwind_Context * context,void * func_arg)447c478bd9Sstevel@tonic-gate posix_stop_func(
457c478bd9Sstevel@tonic-gate 	int version,
467c478bd9Sstevel@tonic-gate 	_Unwind_Action _Unwind_actions,
477c478bd9Sstevel@tonic-gate 	uint64_t exceptionClass,
487c478bd9Sstevel@tonic-gate 	struct _Unwind_Exception *exceptionObject,
497c478bd9Sstevel@tonic-gate 	struct _Unwind_Context *context,
507c478bd9Sstevel@tonic-gate 	void *func_arg)
517c478bd9Sstevel@tonic-gate {
527c478bd9Sstevel@tonic-gate 	__cleanup_t **headp = (__cleanup_t **)func_arg;
537c478bd9Sstevel@tonic-gate 	__cleanup_t *head;
547c478bd9Sstevel@tonic-gate 	uint64_t cfa;
557c478bd9Sstevel@tonic-gate 
567c478bd9Sstevel@tonic-gate 	/*
577c478bd9Sstevel@tonic-gate 	 * If we have reached the origin of the stack, exit now.
587c478bd9Sstevel@tonic-gate 	 */
597c478bd9Sstevel@tonic-gate 	cfa = _Unwind_GetCFA(context);
607c478bd9Sstevel@tonic-gate 	if (cfa == 0 || _Unwind_GetGR(context, RET_ADD) == 0) {
617c478bd9Sstevel@tonic-gate 		_Unwind_DeleteException(exceptionObject);
627c478bd9Sstevel@tonic-gate 		_thrp_exit();
637c478bd9Sstevel@tonic-gate 		thr_panic("posix_stop_func(): _thrp_exit() returned");
647c478bd9Sstevel@tonic-gate 	}
657c478bd9Sstevel@tonic-gate 
667c478bd9Sstevel@tonic-gate 	/*
677c478bd9Sstevel@tonic-gate 	 * Call all Posix cleanup handlers for this frame.
687c478bd9Sstevel@tonic-gate 	 */
697c478bd9Sstevel@tonic-gate 	while ((head = *headp) != NULL &&
707c478bd9Sstevel@tonic-gate 	    (caddr_t)cfa == head->fp + CFA_ADJUST) {
717c478bd9Sstevel@tonic-gate 		*headp = head->next;
727c478bd9Sstevel@tonic-gate 		(*head->func)(head->arg);
737c478bd9Sstevel@tonic-gate 	}
747c478bd9Sstevel@tonic-gate 
757c478bd9Sstevel@tonic-gate 	return (_URC_NO_REASON);
767c478bd9Sstevel@tonic-gate }
777c478bd9Sstevel@tonic-gate 
787c478bd9Sstevel@tonic-gate /*
797c478bd9Sstevel@tonic-gate  * _ex_unwind() is provided by libCrun to perform stack unwinding
807c478bd9Sstevel@tonic-gate  * and calling C++ destructors as needed, interleaved with calling
817c478bd9Sstevel@tonic-gate  * Posix cleanup handlers along the way.  If libCrun is not present
827c478bd9Sstevel@tonic-gate  * we just need to call the Posix cleanup handlers.
837c478bd9Sstevel@tonic-gate  */
847c478bd9Sstevel@tonic-gate 
857c478bd9Sstevel@tonic-gate /* ARGSUSED */
867c478bd9Sstevel@tonic-gate void
_thrp_unwind(void * dummy)877c478bd9Sstevel@tonic-gate _thrp_unwind(void *dummy)
887c478bd9Sstevel@tonic-gate {
897c478bd9Sstevel@tonic-gate 	ulwp_t *self = curthread;
907c478bd9Sstevel@tonic-gate 	__cleanup_t **headp = &self->ul_clnup_hdr;
917c478bd9Sstevel@tonic-gate 	__cleanup_t *head;
927c478bd9Sstevel@tonic-gate 	void (*fptr)(_Unwind_Stop_Fn, void *);
937c478bd9Sstevel@tonic-gate 
947c478bd9Sstevel@tonic-gate 	/* Do this once per thread exit, not once per unwind frame */
957c478bd9Sstevel@tonic-gate 	if (self->ul_ex_unwind == NULL &&
967c478bd9Sstevel@tonic-gate 	    (self->ul_ex_unwind = dlsym(RTLD_PROBE, "_ex_unwind")) == NULL)
977c478bd9Sstevel@tonic-gate 		self->ul_ex_unwind = (void *)-1;
987c478bd9Sstevel@tonic-gate 
997c478bd9Sstevel@tonic-gate 	if (self->ul_ex_unwind == (void *)-1)
1007c478bd9Sstevel@tonic-gate 		fptr = NULL;
1017c478bd9Sstevel@tonic-gate 	else
1027c478bd9Sstevel@tonic-gate 		fptr = (void (*)())self->ul_ex_unwind;
1037c478bd9Sstevel@tonic-gate 
1047c478bd9Sstevel@tonic-gate 	/*
1057c478bd9Sstevel@tonic-gate 	 * Call _ex_unwind() if it is present (C++ loaded),
1067c478bd9Sstevel@tonic-gate 	 * else just call the Posix cleanup handlers.
1077c478bd9Sstevel@tonic-gate 	 */
1087c478bd9Sstevel@tonic-gate 	if (fptr != NULL)
1097c478bd9Sstevel@tonic-gate 		(*fptr)(posix_stop_func, headp);
1107c478bd9Sstevel@tonic-gate 
1117c478bd9Sstevel@tonic-gate 	/*
1127c478bd9Sstevel@tonic-gate 	 * Call all remaining Posix cleanup handlers.
1137c478bd9Sstevel@tonic-gate 	 */
1147c478bd9Sstevel@tonic-gate 	while ((head = *headp) != NULL) {
1157c478bd9Sstevel@tonic-gate 		*headp = head->next;
1167c478bd9Sstevel@tonic-gate 		(*head->func)(head->arg);
1177c478bd9Sstevel@tonic-gate 	}
1187c478bd9Sstevel@tonic-gate 
1197c478bd9Sstevel@tonic-gate 	_thrp_exit();
1207c478bd9Sstevel@tonic-gate 	thr_panic("_thrp_unwind(): _thrp_exit() returned");
1217c478bd9Sstevel@tonic-gate }
122