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#ifndef	_LIBC_I386_INC_SYS_H
28#define	_LIBC_I386_INC_SYS_H
29
30#pragma ident	"%Z%%M%	%I%	%E% SMI"
31
32/*
33 * This file defines common code sequences for system calls.
34 */
35#include <sys/asm_linkage.h>
36#include <sys/syscall.h>
37#include <sys/errno.h>
38
39#define	_prologue_			\
40	pushl	%ebx;			\
41	call	9f;			\
429:					\
43	popl	%ebx;			\
44	addl	$_GLOBAL_OFFSET_TABLE_ + [. - 9b], %ebx
45
46#define	_epilogue_			\
47	popl	%ebx
48
49#define	_fref_(name)	name@PLT
50#define	_daref_(name)	name@GOT(%ebx)
51#define	_sref_(name)	name@GOTOFF(%ebx)
52#define	_esp_(offset)	offset+4(%esp)	/* add 4 for the saved %ebx */
53
54/*
55 * Define the external symbols __cerror and __cerror64 for all files.
56 */
57	.globl	__cerror
58	.globl	__cerror64
59
60/*
61 * __SYSCALLINT provides the basic trap sequence.  It assumes that an entry
62 * of the form SYS_name exists (probably from sys/syscall.h).
63 */
64
65#define	__SYSCALLINT(name)		\
66	/* CSTYLED */			\
67	movl	$SYS_/**/name, %eax;	\
68	int	$T_SYSCALLINT
69
70/*
71 * __SYSENTER provides a faster variant that is only able to
72 * return rval1.  Note that %ecx and %edx are ALWAYS smashed.
73 */
74#define	__SYSENTER(name)		\
75	call	8f;			\
768:	popl	%edx;			\
77	/* CSTYLED */			\
78	movl	$SYS_/**/name, %eax;	\
79	movl	%esp, %ecx;		\
80	add	$[9f - 8b], %edx;	\
81	sysenter;			\
829:
83
84/*
85 * __SYSCALL provides a faster variant on processors and kernels
86 * that support it.  Note that %ecx is ALWAYS smashed.
87 */
88#define	__SYSCALL(name)			\
89	/* CSTYLED */			\
90	movl	$SYS_/**/name, %eax;	\
91	.byte	0xf, 0x5	/* syscall */
92
93#if defined(_SYSC_INSN)
94#define	SYSTRAP_RVAL1(name)	__SYSCALL(name)
95#define	SYSTRAP_RVAL2(name)	__SYSCALL(name)
96#define	SYSTRAP_2RVALS(name)	__SYSCALL(name)
97#define	SYSTRAP_64RVAL(name)	__SYSCALL(name)
98#else	/* _SYSC_INSN */
99#if defined(_SEP_INSN)
100#define	SYSTRAP_RVAL1(name)	__SYSENTER(name)
101#else	/* _SEP_INSN */
102#define	SYSTRAP_RVAL1(name)	__SYSCALLINT(name)
103#endif	/* _SEP_INSN */
104#define	SYSTRAP_RVAL2(name)	__SYSCALLINT(name)
105#define	SYSTRAP_2RVALS(name)	__SYSCALLINT(name)
106#define	SYSTRAP_64RVAL(name)	__SYSCALLINT(name)
107#endif	/* _SYSC_INSN */
108
109/*
110 * SYSFASTTRAP provides the fast system call trap sequence.  It assumes
111 * that an entry of the form T_name exists (probably from sys/trap.h).
112 */
113#define	SYSFASTTRAP(name)		\
114	/* CSTYLED */			\
115	movl	$T_/**/name, %eax;	\
116	int	$T_FASTTRAP
117
118/*
119 * SYSCERROR provides the sequence to branch to __cerror if an error is
120 * indicated by the carry-bit being set upon return from a trap.
121 */
122#define	SYSCERROR		\
123	jb	__cerror
124
125/*
126 * SYSCERROR64 provides the sequence to branch to __cerror64 if an error is
127 * indicated by the carry-bit being set upon return from a trap.
128 */
129#define	SYSCERROR64		\
130	jb	__cerror64
131
132/*
133 * SYSLWPERR provides the sequence to return 0 on a successful trap
134 * and the error code if unsuccessful.
135 * Error is indicated by the carry-bit being set upon return from a trap.
136 */
137#define	SYSLWPERR			\
138	jae	1f;			\
139	cmpl	$ERESTART, %eax;	\
140	jne	2f;			\
141	movl	$EINTR, %eax;		\
142	jmp	2f;			\
1431:					\
144	xorl	%eax, %eax;		\
1452:
146
147/*
148 * SYSREENTRY provides the entry sequence for restartable system calls.
149 */
150#define	SYSREENTRY(name)	\
151/* CSTYLED */			\
152.restart_/**/name:		\
153	ENTRY(name)
154
155/*
156 * SYSRESTART provides the error handling sequence for restartable
157 * system calls.
158 */
159#define	SYSRESTART(name)		\
160	jae	1f;			\
161	cmpl	$ERESTART, %eax;	\
162	je	name;			\
163	jmp	__cerror;		\
1641:
165
166/*
167 * SYSINTR_RESTART provides the error handling sequence for restartable
168 * system calls in case of EINTR or ERESTART.
169 */
170#define	SYSINTR_RESTART(name)		\
171	jae	1f;			\
172	cmpl	$ERESTART, %eax;	\
173	je	name;			\
174	cmpl	$EINTR, %eax;		\
175	je	name;			\
176	jmp	2f;			\
1771:					\
178	xorl	%eax, %eax;		\
1792:
180
181/*
182 * SYSCALL provides the standard (i.e.: most common) system call sequence.
183 */
184#define	SYSCALL(name)		\
185	ENTRY(name);		\
186	SYSTRAP_2RVALS(name);	\
187	SYSCERROR
188
189#define	SYSCALL_RVAL1(name)	\
190	ENTRY(name);		\
191	SYSTRAP_RVAL1(name);	\
192	SYSCERROR
193
194/*
195 * SYSCALL64 provides the standard (i.e.: most common) system call sequence
196 * for system calls that return 64-bit values.
197 */
198#define	SYSCALL64(name)		\
199	ENTRY(name);		\
200	SYSTRAP_64RVAL(name);	\
201	SYSCERROR64
202
203/*
204 * SYSCALL_RESTART provides the most common restartable system call sequence.
205 */
206#define	SYSCALL_RESTART(name)	\
207	SYSREENTRY(name);	\
208	SYSTRAP_2RVALS(name);	\
209	/* CSTYLED */		\
210	SYSRESTART(.restart_/**/name)
211
212#define	SYSCALL_RESTART_RVAL1(name)	\
213	SYSREENTRY(name);		\
214	SYSTRAP_RVAL1(name);		\
215	/* CSTYLED */			\
216	SYSRESTART(.restart_/**/name)
217
218/*
219 * SYSCALL2 provides a common system call sequence when the entry name
220 * is different than the trap name.
221 */
222#define	SYSCALL2(entryname, trapname)	\
223	ENTRY(entryname);		\
224	SYSTRAP_2RVALS(trapname);	\
225	SYSCERROR
226
227#define	SYSCALL2_RVAL1(entryname, trapname)	\
228	ENTRY(entryname);			\
229	SYSTRAP_RVAL1(trapname);		\
230	SYSCERROR
231
232/*
233 * SYSCALL2_RESTART provides a common restartable system call sequence when the
234 * entry name is different than the trap name.
235 */
236#define	SYSCALL2_RESTART(entryname, trapname)	\
237	SYSREENTRY(entryname);			\
238	SYSTRAP_2RVALS(trapname);		\
239	/* CSTYLED */				\
240	SYSRESTART(.restart_/**/entryname)
241
242#define	SYSCALL2_RESTART_RVAL1(entryname, trapname)	\
243	SYSREENTRY(entryname);				\
244	SYSTRAP_RVAL1(trapname);			\
245	/* CSTYLED */					\
246	SYSRESTART(.restart_/**/entryname)
247
248/*
249 * SYSCALL_NOERROR provides the most common system call sequence for those
250 * system calls which don't check the error return (carry bit).
251 */
252#define	SYSCALL_NOERROR(name)	\
253	ENTRY(name);		\
254	SYSTRAP_2RVALS(name)
255
256#define	SYSCALL_NOERROR_RVAL1(name)	\
257	ENTRY(name);			\
258	SYSTRAP_RVAL1(name)
259
260/*
261 * Standard syscall return sequence, return code equal to rval1.
262 */
263#define	RET			\
264	ret
265
266/*
267 * Syscall return sequence, return code equal to rval2.
268 */
269#define	RET2			\
270	movl	%edx, %eax;	\
271	ret
272
273/*
274 * Syscall return sequence with return code forced to zero.
275 */
276#define	RETC			\
277	xorl	%eax, %eax;	\
278	ret
279
280#endif	/* _LIBC_I386_INC_SYS_H */
281