xref: /titanic_44/usr/src/lib/libc/i386/sys/door.s (revision 20e6d5c536ad5b300e7fafb6a92e13040f492977)
1/*
2 * CDDL HEADER START
3 *
4 * The contents of this file are subject to the terms of the
5 * Common Development and Distribution License (the "License").
6 * You may not use this file except in compliance with the License.
7 *
8 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
9 * or http://www.opensolaris.org/os/licensing.
10 * See the License for the specific language governing permissions
11 * and limitations under the License.
12 *
13 * When distributing Covered Code, include this CDDL HEADER in each
14 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
15 * If applicable, add the following below this CDDL HEADER, with the
16 * fields enclosed by brackets "[]" replaced with your own identifying
17 * information: Portions Copyright [yyyy] [name of copyright owner]
18 *
19 * CDDL HEADER END
20 */
21
22/*
23 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27#pragma ident	"%Z%%M%	%I%	%E% SMI"
28
29	.file	"%M%"
30
31#include "SYS.h"
32#include <sys/door.h>
33
34	/*
35	 * weak aliases for public interfaces
36	 */
37	ANSI_PRAGMA_WEAK2(door_bind,__door_bind,function)
38	ANSI_PRAGMA_WEAK2(door_getparam,__door_getparam,function)
39	ANSI_PRAGMA_WEAK2(door_info,__door_info,function)
40	ANSI_PRAGMA_WEAK2(door_revoke,__door_revoke,function)
41	ANSI_PRAGMA_WEAK2(door_setparam,__door_setparam,function)
42	ANSI_PRAGMA_WEAK2(door_unbind,__door_unbind,function)
43
44/*
45 * Offsets within struct door_results
46 */
47#define	DOOR_COOKIE	_MUL(0, CLONGSIZE)
48#define	DOOR_DATA_PTR	_MUL(1, CLONGSIZE)
49#define	DOOR_DATA_SIZE	_MUL(2, CLONGSIZE)
50#define	DOOR_DESC_PTR	_MUL(3, CLONGSIZE)
51#define	DOOR_DESC_SIZE	_MUL(4, CLONGSIZE)
52#define	DOOR_PC		_MUL(5, CLONGSIZE)
53#define	DOOR_SERVERS	_MUL(6, CLONGSIZE)
54#define	DOOR_INFO_PTR	_MUL(7, CLONGSIZE)
55
56/*
57 * All of the syscalls except door_return() follow the same pattern.
58 * The subcode goes in argument 6, which means we have to copy our
59 * arguments into a new bit of stack, large enough to include the
60 * subcode.  We fill the unused positions with zeros.
61 */
62#define	DOOR_SYSCALL(name, code, copy_args)				\
63	ENTRY(name);							\
64	pushl	%ebp;							\
65	movl	%esp, %ebp;						\
66	pushl	$code;		/* syscall subcode, arg 6 */		\
67	pushl	$0;		/* dummy arg 5 */			\
68	pushl	$0;		/* dummy arg 4 */			\
69	copy_args;		/* args 1, 2, 3 */			\
70	pushl	$0;		/* dummy return PC */			\
71	SYSTRAP_RVAL1(door);						\
72	jae	1f;							\
73	addl	$28, %esp;						\
74	leave;								\
75	jmp	__cerror;						\
761:									\
77	addl	$28, %esp;						\
78	leave;								\
79	ret;								\
80	SET_SIZE(name)
81
82#define	COPY_0								\
83	pushl	$0;		/* dummy */				\
84	pushl	$0;		/* dummy */				\
85	pushl	$0		/* dummy */
86
87#define	COPY_1								\
88	pushl	$0;		/* dummy */				\
89	pushl	$0;		/* dummy */				\
90	pushl	8(%ebp)		/* 1 */
91
92#define	COPY_2								\
93	pushl	$0;		/* dummy */				\
94	pushl	12(%ebp);	/* 2 */					\
95	pushl	8(%ebp)		/* 1 */
96
97#define	COPY_3								\
98	pushl	16(%ebp);	/* 3 */					\
99	pushl	12(%ebp);	/* 2 */					\
100	pushl	8(%ebp)		/* 1 */
101
102	DOOR_SYSCALL(__door_bind,	DOOR_BIND,	COPY_1)
103	DOOR_SYSCALL(__door_call,	DOOR_CALL,	COPY_2)
104	DOOR_SYSCALL(__door_create,	DOOR_CREATE,	COPY_3)
105	DOOR_SYSCALL(__door_getparam,	DOOR_GETPARAM,	COPY_3)
106	DOOR_SYSCALL(__door_info,	DOOR_INFO,	COPY_2)
107	DOOR_SYSCALL(__door_revoke,	DOOR_REVOKE,	COPY_1)
108	DOOR_SYSCALL(__door_setparam,	DOOR_SETPARAM,	COPY_3)
109	DOOR_SYSCALL(__door_ucred,	DOOR_UCRED,	COPY_1)
110	DOOR_SYSCALL(__door_unbind,	DOOR_UNBIND,	COPY_0)
111	DOOR_SYSCALL(__door_unref,	DOOR_UNREFSYS,	COPY_0)
112
113/*
114 * int
115 * __door_return(
116 *	void 			*data_ptr,
117 *	size_t			data_size,	(in bytes)
118 *	door_return_desc_t	*door_ptr,	(holds returned desc info)
119 *	caddr_t			stack_base,
120 *	size_t			stack_size)
121 */
122	ENTRY(__door_return)
123	movl	%esp, %edx		/ Save pointer to args
124
125	pushl	%edi			/ save old %edi and %esi
126	pushl	%esi			/ and use them to hold the
127	movl	16(%edx), %esi		/ stack pointer and
128	movl	20(%edx), %edi		/ size.
129
130	pushl	$DOOR_RETURN		/ syscall subcode
131	pushl	%edi			/ size of user stack
132	pushl	%esi			/ base of user stack
133	pushl	12(%edx)		/ desc arguments ptr
134	pushl	8(%edx)			/ data size
135	pushl	4(%edx)			/ data ptr
136	pushl	0(%edx)			/ dummy return PC
137
138door_restart:
139	SYSTRAP_RVAL1(door)
140	jb	2f			/* errno is set */
141	/*
142	 * On return, we're serving a door_call.  Our stack looks like this:
143	 *
144	 *		descriptors (if any)
145	 *		data (if any)
146	 *	 sp->	struct door_results
147	 *
148	 * struct door_results has the arguments in place for the server proc,
149	 * so we just call it directly.
150	 */
151	movl	DOOR_SERVERS(%esp), %eax
152	andl	%eax, %eax	/* test nservers */
153	jg	1f
154	/*
155	 * this is the last server thread - call creation func for more
156	 */
157	movl	DOOR_INFO_PTR(%esp), %eax
158	_prologue_
159	pushl	%eax		/* door_info_t * */
160	movl	_daref_(door_server_func), %eax
161	movl	0(%eax), %eax
162	call	*%eax		/* call create function */
163	addl	$4, %esp
164	_epilogue_
1651:
166	/* Call the door server function now */
167	movl	DOOR_PC(%esp), %eax
168	call	*%eax
169	/* Exit the thread if we return here */
170	pushl	$0
171	call	_thrp_terminate
172	/* NOTREACHED */
1732:
174	/*
175	 * Error during door_return call.  Repark the thread in the kernel if
176	 * the error code is EINTR (or ERESTART) and this lwp is still part
177	 * of the same process.
178	 *
179	 * If the error code is EINTR or ERESTART, our stack may have been
180	 * corrupted by a partial door call, so we refresh the system call
181	 * arguments.
182	 */
183	cmpl	$ERESTART, %eax		/* ERESTART is same as EINTR */
184	jne	3f
185	movl	$EINTR, %eax
1863:
187	cmpl	$EINTR, %eax		/* interrupted while waiting? */
188	jne	4f			/* if not, return the error */
189	_prologue_
190	call	getpid
191	movl	_daref_(door_create_pid), %edx
192	movl	0(%edx), %edx
193	_epilogue_
194	cmpl	%eax, %edx		/* same process? */
195	movl	$EINTR, %eax	/* if no, return EINTR (child of forkall) */
196	jne	4f
197
198	movl	$0, 4(%esp)		/* clear arguments and restart */
199	movl	$0, 8(%esp)
200	movl	$0, 12(%esp)
201	movl	%esi, 16(%esp)		/* refresh sp */
202	movl	%edi, 20(%esp)		/* refresh ssize */
203	movl	$DOOR_RETURN, 24(%esp)	/* refresh syscall subcode */
204	jmp	door_restart
2054:
206	/* Something bad happened during the door_return */
207	addl	$28, %esp
208	popl	%esi
209	popl	%edi
210	jmp	__cerror
211	SET_SIZE(__door_return)
212