1/*
2 * Linux/PARISC Project (http://www.parisc-linux.org/)
3 *
4 * HP-UX System Call Wrapper routines and System Call Return Path
5 *
6 * Copyright (C) 2000 Hewlett-Packard (John Marvin)
7 *
8 *    This program is free software; you can redistribute it and/or modify
9 *    it under the terms of the GNU General Public License as published by
10 *    the Free Software Foundation; either version 2, or (at your option)
11 *    any later version.
12 *
13 *    This program is distributed in the hope that it will be useful,
14 *    but WITHOUT ANY WARRANTY; without even the implied warranty of
15 *    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
16 *    GNU General Public License for more details.
17 *
18 *    You should have received a copy of the GNU General Public License
19 *    along with this program; if not, write to the Free Software
20 *    Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
21 */
22
23#ifdef CONFIG_64BIT
24#warning PA64 support needs more work...did first cut
25#endif
26
27#include <asm/asm-offsets.h>
28#include <asm/assembly.h>
29#include <asm/signal.h>
30#include <linux/linkage.h>
31
32	.level	LEVEL
33	.text
34
35	/* These should probably go in a header file somewhere.
36	 * They are duplicated in kernel/wrappers.S
37	 * Possibly we should consider consolidating these
38	 * register save/restore macros.
39	 */
40	.macro	reg_save regs
41#ifdef CONFIG_64BIT
42#warning NEEDS WORK for 64-bit
43#endif
44	STREG	%r3, PT_GR3(\regs)
45	STREG	%r4, PT_GR4(\regs)
46	STREG	%r5, PT_GR5(\regs)
47	STREG	%r6, PT_GR6(\regs)
48	STREG	%r7, PT_GR7(\regs)
49	STREG	%r8, PT_GR8(\regs)
50	STREG	%r9, PT_GR9(\regs)
51	STREG	%r10,PT_GR10(\regs)
52	STREG	%r11,PT_GR11(\regs)
53	STREG	%r12,PT_GR12(\regs)
54	STREG	%r13,PT_GR13(\regs)
55	STREG	%r14,PT_GR14(\regs)
56	STREG	%r15,PT_GR15(\regs)
57	STREG	%r16,PT_GR16(\regs)
58	STREG	%r17,PT_GR17(\regs)
59	STREG	%r18,PT_GR18(\regs)
60	.endm
61
62	.macro	reg_restore regs
63	LDREG	PT_GR3(\regs), %r3
64	LDREG	PT_GR4(\regs), %r4
65	LDREG	PT_GR5(\regs), %r5
66	LDREG	PT_GR6(\regs), %r6
67	LDREG	PT_GR7(\regs), %r7
68	LDREG	PT_GR8(\regs), %r8
69	LDREG	PT_GR9(\regs), %r9
70	LDREG	PT_GR10(\regs),%r10
71	LDREG	PT_GR11(\regs),%r11
72	LDREG	PT_GR12(\regs),%r12
73	LDREG	PT_GR13(\regs),%r13
74	LDREG	PT_GR14(\regs),%r14
75	LDREG	PT_GR15(\regs),%r15
76	LDREG	PT_GR16(\regs),%r16
77	LDREG	PT_GR17(\regs),%r17
78	LDREG	PT_GR18(\regs),%r18
79	.endm
80
81
82	.import sys_fork
83
84ENTRY(hpux_fork_wrapper)
85	ldo	TASK_REGS-TASK_SZ_ALGN-64(%r30),%r1	    ;! get pt regs
86							    ;! pointer in task
87	reg_save %r1
88
89	STREG	%r2,-20(%r30)
90	ldo	64(%r30),%r30
91	STREG	%r2,PT_GR19(%r1)	;! save for child
92	STREG	%r30,PT_GR21(%r1)	;! save for child
93
94	LDREG	PT_GR30(%r1),%r25
95	mtctl	%r25,%cr29
96	copy	%r1,%r24
97	bl	sys_clone,%r2
98	ldi	SIGCHLD,%r26
99
100	LDREG	-84(%r30),%r2
101fork_return:
102	ldo	-64(%r30),%r30
103	ldo	TASK_REGS-TASK_SZ_ALGN-64(%r30),%r1	    ;! get pt regs
104
105	reg_restore %r1
106
107	/*
108	 * HP-UX wants pid (child gets parent pid, parent gets child pid)
109	 * in r28 and a flag in r29 (r29 == 1 for child, 0 for parent).
110	 * Linux fork returns 0 for child, pid for parent. Since HP-UX
111	 * libc stub throws away parent pid and returns 0 for child,
112	 * we'll just return 0 for parent pid now. Only applications
113	 * that jump directly to the gateway page (not supported) will
114	 * know the difference. We can fix this later if necessary.
115	 */
116
117	ldo	-1024(%r0),%r1
118	comb,>>=,n %r28,%r1,fork_exit  /* just let the syscall exit handle it */
119	or,=	%r28,%r0,%r0
120	or,tr	%r0,%r0,%r29	/* r28 <> 0, we are parent, set r29 to 0 */
121	ldo	1(%r0),%r29 	/* r28 == 0, we are child,  set r29 to 1 */
122
123fork_exit:
124	bv	%r0(%r2)
125	nop
126ENDPROC(hpux_fork_wrapper)
127
128	/* Set the return value for the child */
129
130ENTRY(hpux_child_return)
131#if defined(CONFIG_SMP) || defined(CONFIG_PREEMPT)
132	bl,n	schedule_tail, %r2
133#endif
134
135	LDREG	TASK_PT_GR19-TASK_SZ_ALGN-128(%r30),%r2
136	b fork_return
137	copy %r0,%r28
138ENDPROC(hpux_child_return)
139
140	.import hpux_execve
141
142ENTRY(hpux_execv_wrapper)
143	copy %r0,%r24  /* NULL environment */
144
145ENTRY(hpux_execve_wrapper)
146
147	ldo	TASK_REGS-TASK_SZ_ALGN-64(%r30),%r1	    ;! get pt regs
148
149	/*
150	 * Do we need to save/restore r3-r18 here?
151	 * I don't think so. why would new thread need old
152	 * threads registers?
153	 */
154
155	/* Store arg0, arg1 and arg2 so that hpux_execve will find them */
156
157	STREG %r26,PT_GR26(%r1)
158	STREG %r25,PT_GR25(%r1)
159	STREG %r24,PT_GR24(%r1)
160
161	STREG %r2,-20(%r30)
162	ldo 64(%r30),%r30
163	bl hpux_execve,%r2
164	copy %r1,%arg0
165
166	ldo -64(%r30),%r30
167	LDREG	-20(%r30),%r2
168
169	/* If exec succeeded we need to load the args */
170
171	ldo -1024(%r0),%r1
172	comb,>>= %r28,%r1,exec_error
173	copy %r2,%r19
174	ldo	-TASK_SZ_ALGN-64(%r30),%r1	   ;! get task ptr
175	LDREG	TASK_PT_GR26(%r1),%r26
176	LDREG	TASK_PT_GR25(%r1),%r25
177	LDREG	TASK_PT_GR24(%r1),%r24
178	LDREG	TASK_PT_GR23(%r1),%r23
179	copy %r0,%r2	/* Flag to syscall_exit not to clear args */
180
181exec_error:
182	bv %r0(%r19)
183	nop
184ENDPROC(hpux_execv_wrapper)
185
186	.import hpux_pipe
187
188	/* HP-UX expects pipefd's returned in r28 & r29 */
189
190ENTRY(hpux_pipe_wrapper)
191	STREG %r2,-20(%r30)
192	ldo 64(%r30),%r30
193	bl hpux_pipe,%r2
194	ldo -56(%r30),%r26 /* pass local array to hpux_pipe */
195
196
197	ldo -1024(%r0),%r1
198	comb,>>= %r28,%r1,pipe_exit /* let syscall exit handle it */
199	LDREG	-84(%r30),%r2
200
201	/* if success, load fd's from stack array */
202
203	LDREG	-56(%r30),%r28
204	LDREG	-52(%r30),%r29
205
206pipe_exit:
207	bv %r0(%r2)
208	ldo -64(%r30),%r30
209ENDPROC(hpux_pipe_wrapper)
210
211	.import syscall_exit
212
213ENTRY(hpux_syscall_exit)
214	/*
215	 *
216	 * HP-UX call return conventions:
217	 *
218	 * if error:
219	 *	 r22 = 1
220	 *	 r28 = errno value
221	 *	 r29 = secondary return value
222	 * else
223	 *	 r22 = 0
224	 *	 r28 = return value
225	 *	 r29 = secondary return value
226	 *
227	 * For now, we'll just check to see if r28 is < (unsigned long)-1024
228	 * (to handle addresses > 2 Gb) and if so set r22 to zero. If not,
229	 * we'll complement r28 and set r22 to 1. Wrappers will be
230	 * needed for syscalls that care about the secondary return value.
231	 * The wrapper may also need a way of avoiding the following code,
232	 * but we'll deal with that when it becomes necessary.
233	 */
234
235	ldo -1024(%r0),%r1
236	comb,<< %r28,%r1,no_error
237	copy %r0,%r22
238	subi 0,%r28,%r28
239	ldo 1(%r0),%r22
240
241no_error:
242	b,n syscall_exit
243ENDPROC(hpux_syscall_exit)
244
245	.import hpux_unimplemented
246
247ENTRY(hpux_unimplemented_wrapper)
248	b hpux_unimplemented
249	STREG %r22,-64(%r30)  /* overwrite arg8 with syscall number */
250ENDPROC(hpux_unimplemented_wrapper)
251