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_SPARC_INC_SYS_H
28#define	_LIBC_SPARC_INC_SYS_H
29
30#pragma ident	"%Z%%M%	%I%	%E% SMI"
31
32/*
33 * This file defines common code sequences for system calls.  Note that
34 * it is assumed that __cerror is within the short branch distance from
35 * all the traps (so that a simple bcs can follow the trap, rather than
36 * a position independent code sequence.)  Ditto for __cerror64.
37 */
38
39#include <sys/asm_linkage.h>
40#include <sys/syscall.h>
41#include <sys/errno.h>
42
43/*
44 * While it's tempting to imagine we could use 'rd %pc' here,
45 * in fact it's a rather slow operation that consumes many
46 * cycles, so we use the usual side-effect of 'call' instead.
47 */
48#define	PIC_SETUP(r)						\
49	mov	%o7, %g1;					\
509:	call	8f;						\
51	sethi	%hi(_GLOBAL_OFFSET_TABLE_ - (9b - .)), %r;	\
528:	or	%r, %lo(_GLOBAL_OFFSET_TABLE_ - (9b - .)), %r;	\
53	add	%r, %o7, %r;					\
54	mov	%g1, %o7
55
56/*
57 * Trap number for system calls
58 */
59#define	SYSCALL_TRAPNUM		8
60#define	FASTSCALL_TRAPNUM	9
61
62/*
63 * Define the external symbols __cerror and __cerror64 for all files.
64 */
65	.global	__cerror
66	.global	__cerror64
67
68/*
69 * __SYSTRAP provides the basic trap sequence.  It assumes that an entry
70 * of the form SYS_name exists (probably from sys/syscall.h).
71 */
72#define	__SYSTRAP(name)			\
73	/* CSTYLED */			\
74	mov	SYS_/**/name, %g1;	\
75	ta	SYSCALL_TRAPNUM
76
77#define	SYSTRAP_RVAL1(name)		__SYSTRAP(name)
78#define	SYSTRAP_RVAL2(name)		__SYSTRAP(name)
79#define	SYSTRAP_2RVALS(name)		__SYSTRAP(name)
80#define	SYSTRAP_64RVAL(name)		__SYSTRAP(name)
81
82/*
83 * SYSFASTTRAP provides the fast system call trap sequence.  It assumes
84 * that an entry of the form ST_name exists (probably from sys/trap.h).
85 */
86#define	SYSFASTTRAP(name)		\
87	/* CSTYLED */			\
88	ta	ST_/**/name
89
90/*
91 * SYSCERROR provides the sequence to branch to __cerror if an error is
92 * indicated by the carry-bit being set upon return from a trap.
93 */
94#define	SYSCERROR			\
95	bcs	__cerror;		\
96	nop
97
98/*
99 * SYSCERROR64 provides the sequence to branch to __cerror64 if an error is
100 * indicated by the carry-bit being set upon return from a trap.
101 */
102#define	SYSCERROR64			\
103	bcs	__cerror64;		\
104	nop
105
106/*
107 * SYSLWPERR provides the sequence to return 0 on a successful trap
108 * and the error code if unsuccessful.
109 * Error is indicated by the carry-bit being set upon return from a trap.
110 */
111#define	SYSLWPERR			\
112	/* CSTYLED */			\
113	bcc,a,pt %icc, 1f;		\
114	clr	%o0;			\
115	cmp	%o0, ERESTART;		\
116	move	%icc, EINTR, %o0;	\
1171:
118
119#define	SAVE_OFFSET	68
120
121/*
122 * SYSREENTRY provides the entry sequence for restartable system calls.
123 */
124#define	SYSREENTRY(name)			\
125	ENTRY(name);				\
126	stn	%o0, [%sp + SAVE_OFFSET];	\
127/* CSTYLED */					\
128.restart_/**/name:
129
130/*
131 * SYSRESTART provides the error handling sequence for restartable
132 * system calls.
133 */
134#define	SYSRESTART(name)					\
135	/* CSTYLED */						\
136	bcc,pt	%icc, 1f;					\
137	cmp	%o0, ERESTART;					\
138	/* CSTYLED */						\
139	be,a,pn	%icc, name;					\
140	ldn	[%sp + SAVE_OFFSET], %o0;			\
141	/* CSTYLED */						\
142	ba,a	__cerror;					\
1431:
144
145/*
146 * SYSINTR_RESTART provides the error handling sequence for restartable
147 * system calls in case of EINTR or ERESTART.
148 */
149#define	SYSINTR_RESTART(name)					\
150	/* CSTYLED */						\
151	bcc,a,pt %icc, 1f;					\
152	clr	%o0;						\
153	cmp	%o0, ERESTART;					\
154	/* CSTYLED */						\
155	be,a,pn	%icc, name;					\
156	ldn	[%sp + SAVE_OFFSET], %o0;			\
157	cmp	%o0, EINTR;					\
158	/* CSTYLED */						\
159	be,a,pn	%icc, name;					\
160	ldn	[%sp + SAVE_OFFSET], %o0;			\
1611:
162
163/*
164 * SYSCALL provides the standard (i.e.: most common) system call sequence.
165 */
166#define	SYSCALL(name)						\
167	ENTRY(name);						\
168	SYSTRAP_2RVALS(name);					\
169	SYSCERROR
170
171#define	SYSCALL_RVAL1(name)					\
172	ENTRY(name);						\
173	SYSTRAP_RVAL1(name);					\
174	SYSCERROR
175
176/*
177 * SYSCALL64 provides the standard (i.e.: most common) system call sequence
178 * for system calls that return 64-bit values.
179 */
180#define	SYSCALL64(name)						\
181	ENTRY(name);						\
182	SYSTRAP_64RVAL(name);					\
183	SYSCERROR64
184
185/*
186 * SYSCALL_RESTART provides the most common restartable system call sequence.
187 */
188#define	SYSCALL_RESTART(name)					\
189	SYSREENTRY(name);					\
190	SYSTRAP_2RVALS(name);					\
191	/* CSTYLED */						\
192	SYSRESTART(.restart_/**/name)
193
194#define	SYSCALL_RESTART_RVAL1(name)				\
195	SYSREENTRY(name);					\
196	SYSTRAP_RVAL1(name);					\
197	/* CSTYLED */						\
198	SYSRESTART(.restart_/**/name)
199
200/*
201 * SYSCALL2 provides a common system call sequence when the entry name
202 * is different than the trap name.
203 */
204#define	SYSCALL2(entryname, trapname)				\
205	ENTRY(entryname);					\
206	SYSTRAP_2RVALS(trapname);				\
207	SYSCERROR
208
209#define	SYSCALL2_RVAL1(entryname, trapname)			\
210	ENTRY(entryname);					\
211	SYSTRAP_RVAL1(trapname);				\
212	SYSCERROR
213
214/*
215 * SYSCALL2_RESTART provides a common restartable system call sequence when the
216 * entry name is different than the trap name.
217 */
218#define	SYSCALL2_RESTART(entryname, trapname)			\
219	SYSREENTRY(entryname);					\
220	SYSTRAP_2RVALS(trapname);				\
221	/* CSTYLED */						\
222	SYSRESTART(.restart_/**/entryname)
223
224#define	SYSCALL2_RESTART_RVAL1(entryname, trapname)		\
225	SYSREENTRY(entryname);					\
226	SYSTRAP_RVAL1(trapname);				\
227	/* CSTYLED */						\
228	SYSRESTART(.restart_/**/entryname)
229
230/*
231 * SYSCALL_NOERROR provides the most common system call sequence for those
232 * system calls which don't check the error return (carry bit).
233 */
234#define	SYSCALL_NOERROR(name)					\
235	ENTRY(name);						\
236	SYSTRAP_2RVALS(name)
237
238#define	SYSCALL_NOERROR_RVAL1(name)				\
239	ENTRY(name);						\
240	SYSTRAP_RVAL1(name)
241
242/*
243 * Standard syscall return sequence, return code equal to rval1.
244 */
245#define	RET			\
246	retl;			\
247	nop
248
249/*
250 * Syscall return sequence, return code equal to rval2.
251 */
252#define	RET2			\
253	retl;			\
254	mov	%o1, %o0
255
256/*
257 * Syscall return sequence with return code forced to zero.
258 */
259#define	RETC			\
260	retl;			\
261	clr	%o0
262
263#endif	/* _LIBC_SPARC_INC_SYS_H */
264