xref: /illumos-gate/usr/src/lib/libc/sparc/inc/SYS.h (revision 9b9d39d2a32ff806d2431dbcc50968ef1e6d46b2)
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 /*
31  * This file defines common code sequences for system calls.  Note that
32  * it is assumed that __cerror is within the short branch distance from
33  * all the traps (so that a simple bcs can follow the trap, rather than
34  * a position independent code sequence.)  Ditto for __cerror64.
35  */
36 
37 #include <sys/asm_linkage.h>
38 #include <sys/syscall.h>
39 #include <sys/errno.h>
40 
41 /*
42  * While it's tempting to imagine we could use 'rd %pc' here,
43  * in fact it's a rather slow operation that consumes many
44  * cycles, so we use the usual side-effect of 'call' instead.
45  */
46 #define	PIC_SETUP(r)						\
47 	mov	%o7, %g1;					\
48 9:	call	8f;						\
49 	sethi	%hi(_GLOBAL_OFFSET_TABLE_ - (9b - .)), %r;	\
50 8:	or	%r, %lo(_GLOBAL_OFFSET_TABLE_ - (9b - .)), %r;	\
51 	add	%r, %o7, %r;					\
52 	mov	%g1, %o7
53 
54 /*
55  * Trap number for system calls
56  */
57 #define	SYSCALL_TRAPNUM		8
58 #define	FASTSCALL_TRAPNUM	9
59 
60 /*
61  * Define the external symbols __cerror and __cerror64 for all files.
62  */
63 	.global	__cerror
64 	.global	__cerror64
65 
66 /*
67  * __SYSTRAP provides the basic trap sequence.  It assumes that an entry
68  * of the form SYS_name exists (probably from sys/syscall.h).
69  */
70 #define	__SYSTRAP(name)			\
71 	/* CSTYLED */			\
72 	mov	SYS_##name, %g1;	\
73 	ta	SYSCALL_TRAPNUM
74 
75 #define	SYSTRAP_RVAL1(name)		__SYSTRAP(name)
76 #define	SYSTRAP_RVAL2(name)		__SYSTRAP(name)
77 #define	SYSTRAP_2RVALS(name)		__SYSTRAP(name)
78 #define	SYSTRAP_64RVAL(name)		__SYSTRAP(name)
79 
80 /*
81  * SYSFASTTRAP provides the fast system call trap sequence.  It assumes
82  * that an entry of the form ST_name exists (probably from sys/trap.h).
83  */
84 #define	SYSFASTTRAP(name)		\
85 	/* CSTYLED */			\
86 	ta	ST_##name
87 
88 /*
89  * SYSCERROR provides the sequence to branch to __cerror if an error is
90  * indicated by the carry-bit being set upon return from a trap.
91  */
92 #define	SYSCERROR			\
93 	bcs	__cerror;		\
94 	nop
95 
96 /*
97  * SYSCERROR64 provides the sequence to branch to __cerror64 if an error is
98  * indicated by the carry-bit being set upon return from a trap.
99  */
100 #define	SYSCERROR64			\
101 	bcs	__cerror64;		\
102 	nop
103 
104 /*
105  * SYSLWPERR provides the sequence to return 0 on a successful trap
106  * and the error code if unsuccessful.
107  * Error is indicated by the carry-bit being set upon return from a trap.
108  */
109 #define	SYSLWPERR			\
110 	/* CSTYLED */			\
111 	bcc,a,pt %icc, 1f;		\
112 	clr	%o0;			\
113 	cmp	%o0, ERESTART;		\
114 	move	%icc, EINTR, %o0;	\
115 1:
116 
117 #define	SAVE_OFFSET	68
118 
119 /*
120  * SYSREENTRY provides the entry sequence for restartable system calls.
121  */
122 #define	SYSREENTRY(name)			\
123 	ENTRY(name);				\
124 	stn	%o0, [%sp + SAVE_OFFSET];	\
125 /* CSTYLED */					\
126 .restart_##name:
127 
128 /*
129  * SYSRESTART provides the error handling sequence for restartable
130  * system calls.
131  */
132 #define	SYSRESTART(name)					\
133 	/* CSTYLED */						\
134 	bcc,pt	%icc, 1f;					\
135 	cmp	%o0, ERESTART;					\
136 	/* CSTYLED */						\
137 	be,a,pn	%icc, name;					\
138 	ldn	[%sp + SAVE_OFFSET], %o0;			\
139 	/* CSTYLED */						\
140 	ba,a	__cerror;					\
141 1:
142 
143 /*
144  * SYSINTR_RESTART provides the error handling sequence for restartable
145  * system calls in case of EINTR or ERESTART.
146  */
147 #define	SYSINTR_RESTART(name)					\
148 	/* CSTYLED */						\
149 	bcc,a,pt %icc, 1f;					\
150 	clr	%o0;						\
151 	cmp	%o0, ERESTART;					\
152 	/* CSTYLED */						\
153 	be,a,pn	%icc, name;					\
154 	ldn	[%sp + SAVE_OFFSET], %o0;			\
155 	cmp	%o0, EINTR;					\
156 	/* CSTYLED */						\
157 	be,a,pn	%icc, name;					\
158 	ldn	[%sp + SAVE_OFFSET], %o0;			\
159 1:
160 
161 /*
162  * SYSCALL provides the standard (i.e.: most common) system call sequence.
163  */
164 #define	SYSCALL(name)						\
165 	ENTRY(name);						\
166 	SYSTRAP_2RVALS(name);					\
167 	SYSCERROR
168 
169 #define	SYSCALL_RVAL1(name)					\
170 	ENTRY(name);						\
171 	SYSTRAP_RVAL1(name);					\
172 	SYSCERROR
173 
174 /*
175  * SYSCALL64 provides the standard (i.e.: most common) system call sequence
176  * for system calls that return 64-bit values.
177  */
178 #define	SYSCALL64(name)						\
179 	ENTRY(name);						\
180 	SYSTRAP_64RVAL(name);					\
181 	SYSCERROR64
182 
183 /*
184  * SYSCALL_RESTART provides the most common restartable system call sequence.
185  */
186 #define	SYSCALL_RESTART(name)					\
187 	SYSREENTRY(name);					\
188 	SYSTRAP_2RVALS(name);					\
189 	/* CSTYLED */						\
190 	SYSRESTART(.restart_##name)
191 
192 #define	SYSCALL_RESTART_RVAL1(name)				\
193 	SYSREENTRY(name);					\
194 	SYSTRAP_RVAL1(name);					\
195 	/* CSTYLED */						\
196 	SYSRESTART(.restart_##name)
197 
198 /*
199  * SYSCALL2 provides a common system call sequence when the entry name
200  * is different than the trap name.
201  */
202 #define	SYSCALL2(entryname, trapname)				\
203 	ENTRY(entryname);					\
204 	SYSTRAP_2RVALS(trapname);				\
205 	SYSCERROR
206 
207 #define	SYSCALL2_RVAL1(entryname, trapname)			\
208 	ENTRY(entryname);					\
209 	SYSTRAP_RVAL1(trapname);				\
210 	SYSCERROR
211 
212 /*
213  * SYSCALL2_RESTART provides a common restartable system call sequence when the
214  * entry name is different than the trap name.
215  */
216 #define	SYSCALL2_RESTART(entryname, trapname)			\
217 	SYSREENTRY(entryname);					\
218 	SYSTRAP_2RVALS(trapname);				\
219 	/* CSTYLED */						\
220 	SYSRESTART(.restart_##entryname)
221 
222 #define	SYSCALL2_RESTART_RVAL1(entryname, trapname)		\
223 	SYSREENTRY(entryname);					\
224 	SYSTRAP_RVAL1(trapname);				\
225 	/* CSTYLED */						\
226 	SYSRESTART(.restart_##entryname)
227 
228 /*
229  * SYSCALL_NOERROR provides the most common system call sequence for those
230  * system calls which don't check the error return (carry bit).
231  */
232 #define	SYSCALL_NOERROR(name)					\
233 	ENTRY(name);						\
234 	SYSTRAP_2RVALS(name)
235 
236 #define	SYSCALL_NOERROR_RVAL1(name)				\
237 	ENTRY(name);						\
238 	SYSTRAP_RVAL1(name)
239 
240 /*
241  * Standard syscall return sequence, return code equal to rval1.
242  */
243 #define	RET			\
244 	retl;			\
245 	nop
246 
247 /*
248  * Syscall return sequence, return code equal to rval2.
249  */
250 #define	RET2			\
251 	retl;			\
252 	mov	%o1, %o0
253 
254 /*
255  * Syscall return sequence with return code forced to zero.
256  */
257 #define	RETC			\
258 	retl;			\
259 	clr	%o0
260 
261 #endif	/* _LIBC_SPARC_INC_SYS_H */
262