xref: /illumos-gate/usr/src/lib/libc/amd64/sys/door.S (revision 5d9d9091f564c198a760790b0bfa72c44e17912b)
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 2009 Sun Microsystems, Inc.  All rights reserved.
24 * Use is subject to license terms.
25 */
26
27	.file	"door.s"
28
29#include "SYS.h"
30#include <sys/door.h>
31
32	/*
33	 * weak aliases for public interfaces
34	 */
35	ANSI_PRAGMA_WEAK2(door_bind,__door_bind,function)
36	ANSI_PRAGMA_WEAK2(door_getparam,__door_getparam,function)
37	ANSI_PRAGMA_WEAK2(door_info,__door_info,function)
38	ANSI_PRAGMA_WEAK2(door_revoke,__door_revoke,function)
39	ANSI_PRAGMA_WEAK2(door_setparam,__door_setparam,function)
40
41/*
42 * Offsets within struct door_results
43 */
44#define	DOOR_COOKIE	_MUL(0, CLONGSIZE)
45#define	DOOR_DATA_PTR	_MUL(1, CLONGSIZE)
46#define	DOOR_DATA_SIZE	_MUL(2, CLONGSIZE)
47#define	DOOR_DESC_PTR	_MUL(3, CLONGSIZE)
48#define	DOOR_DESC_SIZE	_MUL(4, CLONGSIZE)
49#define	DOOR_PC		_MUL(5, CLONGSIZE)
50#define	DOOR_SERVERS	_MUL(6, CLONGSIZE)
51#define	DOOR_INFO_PTR	_MUL(7, CLONGSIZE)
52
53/*
54 * All of the syscalls except door_return() follow the same pattern.  The
55 * subcode goes in %r9, after all of the other arguments.
56 */
57#define	DOOR_SYSCALL(name, code)					\
58	ENTRY(name);							\
59	movq	$code, %r9;		/* subcode */			\
60	SYSTRAP_RVAL1(door);						\
61	SYSCERROR;							\
62	RET;								\
63	SET_SIZE(name)
64
65	DOOR_SYSCALL(__door_bind,	DOOR_BIND)
66	DOOR_SYSCALL(__door_call,	DOOR_CALL)
67	DOOR_SYSCALL(__door_create,	DOOR_CREATE)
68	DOOR_SYSCALL(__door_getparam,	DOOR_GETPARAM)
69	DOOR_SYSCALL(__door_info,	DOOR_INFO)
70	DOOR_SYSCALL(__door_revoke,	DOOR_REVOKE)
71	DOOR_SYSCALL(__door_setparam,	DOOR_SETPARAM)
72	DOOR_SYSCALL(__door_ucred,	DOOR_UCRED)
73	DOOR_SYSCALL(__door_unbind,	DOOR_UNBIND)
74	DOOR_SYSCALL(__door_unref,	DOOR_UNREFSYS)
75
76/*
77 * int
78 * __door_return(
79 *	void 			*data_ptr,
80 *	size_t			data_size,	(in bytes)
81 *	door_return_desc_t	*door_ptr,	(holds returned desc info)
82 *	caddr_t			stack_base,
83 *	size_t			stack_size)
84 */
85	ENTRY(__door_return)
86	pushq	%rbp
87	movq	%rsp, %rbp
88	subq	$0x8, %rsp
89	/*
90	 * Save stack_base (arg4), since %rcx will be trashed if the syscall
91	 * returns via sysret
92	 */
93	movq	%rcx, -0x8(%rbp)
94
95door_restart:
96	movq	$DOOR_RETURN, %r9	/* subcode */
97	SYSTRAP_RVAL1(door)
98	jb	2f			/* errno is set */
99	/*
100	 * On return, we're serving a door_call.  Our stack looks like this:
101	 *
102	 *		descriptors (if any)
103	 *		data (if any)
104	 *	 sp->	struct door_results
105	 */
106	movl	DOOR_SERVERS(%rsp), %eax
107	andl	%eax, %eax	/* test nservers */
108	jg	1f
109	/*
110	 * this is the last server thread - call creation func for more
111	 */
112	movq	DOOR_INFO_PTR(%rsp), %rdi
113	call	door_depletion_cb@PLT
1141:
115	/* Call the door server function now */
116	movq	DOOR_COOKIE(%rsp), %rdi
117	movq	DOOR_DATA_PTR(%rsp), %rsi
118	movq	DOOR_DATA_SIZE(%rsp), %rdx
119	movq	DOOR_DESC_PTR(%rsp), %rcx
120	movq	DOOR_DESC_SIZE(%rsp), %r8
121	movq	DOOR_PC(%rsp), %rax
122	call	*%rax
123	/* Exit the thread if we return here */
124	movq	$0, %rdi
125	call	_thrp_terminate
126	/* NOTREACHED */
1272:
128	/*
129	 * Error during door_return call.  Repark the thread in the kernel if
130	 * the error code is EINTR (or ERESTART) and this lwp is still part
131	 * of the same process.
132	 */
133	cmpl	$ERESTART, %eax		/* ERESTART is same as EINTR */
134	jne	3f
135	movl	$EINTR, %eax
1363:
137	cmpl	$EINTR, %eax		/* interrupted while waiting? */
138	jne	4f			/* if not, return the error */
139
140	call	getpid			/* get current process id */
141	movq	_daref_(door_create_pid), %rdx
142	movl	0(%rdx), %edx
143	cmpl	%eax, %edx		/* same process? */
144	movl	$EINTR, %eax	/* if no, return EINTR (child of forkall) */
145	jne	4f
146
147	movq	$0, %rdi		/* clear arguments and restart */
148	movq	$0, %rsi
149	movq	$0, %rdx
150	movq	-0x8(%rbp), %rcx	/* Restore arg4 (stack_base) */
151	jmp	door_restart
152
1534:
154	leave
155	jmp	__cerror
156	SET_SIZE(__door_return)
157