1/* $NetBSD: linux_syscall.c,v 1.31 2010/12/20 00:25:24 matt Exp $ */
2
3/*-
4 * Copyright (c) 2000 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Jason R. Thorpe of the Numerical Aerospace Simulation Facility,
9 * NASA Ames Research Center, and by Charles M. Hannum.
10 *
11 * Redistribution and use in source and binary forms, with or without
12 * modification, are permitted provided that the following conditions
13 * are met:
14 * 1. Redistributions of source code must retain the above copyright
15 *    notice, this list of conditions and the following disclaimer.
16 * 2. Redistributions in binary form must reproduce the above copyright
17 *    notice, this list of conditions and the following disclaimer in the
18 *    documentation and/or other materials provided with the distribution.
19 *
20 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
21 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
22 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
23 * PURPOSE ARE DISCLAIMED.  IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS
24 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
25 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
26 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
27 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
28 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
29 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
30 * POSSIBILITY OF SUCH DAMAGE.
31 */
32
33/*
34 * Copyright (c) 1999 Christopher G. Demetriou.  All rights reserved.
35 *
36 * Redistribution and use in source and binary forms, with or without
37 * modification, are permitted provided that the following conditions
38 * are met:
39 * 1. Redistributions of source code must retain the above copyright
40 *    notice, this list of conditions and the following disclaimer.
41 * 2. Redistributions in binary form must reproduce the above copyright
42 *    notice, this list of conditions and the following disclaimer in the
43 *    documentation and/or other materials provided with the distribution.
44 * 3. All advertising materials mentioning features or use of this software
45 *    must display the following acknowledgement:
46 *      This product includes software developed by Christopher G. Demetriou
47 *	for the NetBSD Project.
48 * 4. The name of the author may not be used to endorse or promote products
49 *    derived from this software without specific prior written permission
50 *
51 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
52 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
53 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
54 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
55 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
56 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
57 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
58 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
59 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
60 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
61 */
62
63/*
64 * Copyright (c) 1994, 1995, 1996 Carnegie-Mellon University.
65 * All rights reserved.
66 *
67 * Author: Chris G. Demetriou
68 *
69 * Permission to use, copy, modify and distribute this software and
70 * its documentation is hereby granted, provided that both the copyright
71 * notice and this permission notice appear in all copies of the
72 * software, derivative works or modified versions, and any portions
73 * thereof, and that both notices appear in supporting documentation.
74 *
75 * CARNEGIE MELLON ALLOWS FREE USE OF THIS SOFTWARE IN ITS "AS IS"
76 * CONDITION.  CARNEGIE MELLON DISCLAIMS ANY LIABILITY OF ANY KIND
77 * FOR ANY DAMAGES WHATSOEVER RESULTING FROM THE USE OF THIS SOFTWARE.
78 *
79 * Carnegie Mellon requests users of this software to return to
80 *
81 *  Software Distribution Coordinator  or  Software.Distribution@CS.CMU.EDU
82 *  School of Computer Science
83 *  Carnegie Mellon University
84 *  Pittsburgh PA 15213-3890
85 *
86 * any improvements or extensions that they make and grant Carnegie the
87 * rights to redistribute these changes.
88 */
89
90#include <sys/cdefs.h>			/* RCS ID & Copyright macro defns */
91
92__KERNEL_RCSID(0, "$NetBSD: linux_syscall.c,v 1.31 2010/12/20 00:25:24 matt Exp $");
93
94#include <sys/param.h>
95#include <sys/systm.h>
96#include <sys/proc.h>
97#include <sys/signal.h>
98#include <sys/syscall.h>
99#include <sys/syscallvar.h>
100
101#include <machine/cpu.h>
102#include <machine/reg.h>
103#include <machine/alpha.h>
104#include <machine/userret.h>
105
106#include <compat/linux/common/linux_types.h>
107#include <compat/linux/common/linux_errno.h>
108#include <compat/linux/linux_syscall.h>
109#include <compat/linux/common/linux_signal.h>
110#include <compat/linux/common/linux_siginfo.h>
111#include <compat/linux/arch/alpha/linux_machdep.h>
112
113void	linux_syscall_intern(struct proc *);
114void	linux_syscall_plain(struct lwp *, uint64_t, struct trapframe *);
115void	linux_syscall_fancy(struct lwp *, uint64_t, struct trapframe *);
116
117void
118linux_syscall_intern(struct proc *p)
119{
120
121	if (trace_is_enabled(p))
122		p->p_md.md_syscall = linux_syscall_fancy;
123	else
124		p->p_md.md_syscall = linux_syscall_plain;
125}
126
127/*
128 * Process a system call.
129 *
130 * System calls are strange beasts.  They are passed the syscall number
131 * in v0, and the arguments in the registers (as normal).  They return
132 * an error flag in a3 (if a3 != 0 on return, the syscall had an error),
133 * and the return value (if any) in v0.
134 *
135 * The assembly stub takes care of moving the call number into a register
136 * we can get to, and moves all of the argument registers into their places
137 * in the trap frame.  On return, it restores the callee-saved registers,
138 * a3, and v0 from the frame before returning to the user process.
139 */
140void
141linux_syscall_plain(struct lwp *l, uint64_t code, struct trapframe *framep)
142{
143	const struct sysent *callp;
144	int error;
145	uint64_t rval[2];
146	uint64_t *args, copyargs[10];				/* XXX */
147	u_int hidden, nargs;
148	struct proc *p = l->l_proc;
149
150	LWP_CACHE_CREDS(l, p);
151
152	curcpu()->ci_data.cpu_nsyscall++;
153	l->l_md.md_tf = framep;
154
155	callp = p->p_emul->e_sysent;
156
157	switch (code) {
158	case LINUX_SYS_syscall:
159		/* OSF/1 syscall() */
160		code = framep->tf_regs[FRAME_A0];
161		hidden = 1;
162		break;
163	default:
164		hidden = 0;
165		break;
166	}
167
168	code &= (LINUX_SYS_NSYSENT - 1);
169	callp += code;
170
171	nargs = callp->sy_narg + hidden;
172	switch (nargs) {
173	default:
174		error = copyin((void *)alpha_pal_rdusp(), &copyargs[6],
175		    (nargs - 6) * sizeof(uint64_t));
176		if (error)
177			goto bad;
178	case 6:
179		copyargs[5] = framep->tf_regs[FRAME_A5];
180	case 5:
181		copyargs[4] = framep->tf_regs[FRAME_A4];
182	case 4:
183		copyargs[3] = framep->tf_regs[FRAME_A3];
184		copyargs[2] = framep->tf_regs[FRAME_A2];
185		copyargs[1] = framep->tf_regs[FRAME_A1];
186		copyargs[0] = framep->tf_regs[FRAME_A0];
187		args = copyargs;
188		break;
189	case 3:
190	case 2:
191	case 1:
192	case 0:
193		args = &framep->tf_regs[FRAME_A0];
194		break;
195	}
196	args += hidden;
197
198	rval[0] = 0;
199	rval[1] = 0;
200	error = sy_call(callp, l, args, rval);
201
202	switch (error) {
203	case 0:
204		framep->tf_regs[FRAME_V0] = rval[0];
205		framep->tf_regs[FRAME_A4] = rval[1];
206		framep->tf_regs[FRAME_A3] = 0;
207		break;
208	case ERESTART:
209		framep->tf_regs[FRAME_PC] -= 4;
210		break;
211	case EJUSTRETURN:
212		break;
213	default:
214	bad:
215		error = native_to_linux_errno[error];
216		framep->tf_regs[FRAME_V0] = error;
217		framep->tf_regs[FRAME_A3] = 1;
218		break;
219	}
220
221	userret(l);
222}
223
224void
225linux_syscall_fancy(struct lwp *l, uint64_t code, struct trapframe *framep)
226{
227	const struct sysent *callp;
228	int error;
229	uint64_t rval[2];
230	uint64_t *args, copyargs[10];
231	u_int hidden, nargs;
232	struct proc *p = l->l_proc;
233
234	LWP_CACHE_CREDS(l, p);
235
236	curcpu()->ci_data.cpu_nsyscall++;
237	l->l_md.md_tf = framep;
238
239	callp = p->p_emul->e_sysent;
240
241	switch (code) {
242	case LINUX_SYS_syscall:
243		/* OSF/1 syscall() */
244		code = framep->tf_regs[FRAME_A0];
245		hidden = 1;
246		break;
247	default:
248		hidden = 0;
249		break;
250	}
251
252	code &= (LINUX_SYS_NSYSENT - 1);
253	callp += code;
254
255	nargs = callp->sy_narg + hidden;
256	switch (nargs) {
257	default:
258		error = copyin((void *)alpha_pal_rdusp(), &copyargs[6],
259		    (nargs - 6) * sizeof(uint64_t));
260		if (error) {
261			args = copyargs;
262			goto bad;
263		}
264	case 6:
265		copyargs[5] = framep->tf_regs[FRAME_A5];
266	case 5:
267		copyargs[4] = framep->tf_regs[FRAME_A4];
268	case 4:
269		copyargs[3] = framep->tf_regs[FRAME_A3];
270		copyargs[2] = framep->tf_regs[FRAME_A2];
271		copyargs[1] = framep->tf_regs[FRAME_A1];
272		copyargs[0] = framep->tf_regs[FRAME_A0];
273		args = copyargs;
274		break;
275	case 3:
276	case 2:
277	case 1:
278	case 0:
279		args = &framep->tf_regs[FRAME_A0];
280		break;
281	}
282	args += hidden;
283
284
285	if ((error = trace_enter(code, args, callp->sy_narg)) != 0)
286		goto out;
287
288	rval[0] = 0;
289	rval[1] = 0;
290	error = sy_call(callp, l, args, rval);
291out:
292	switch (error) {
293	case 0:
294		framep->tf_regs[FRAME_V0] = rval[0];
295		framep->tf_regs[FRAME_A4] = rval[1];
296		framep->tf_regs[FRAME_A3] = 0;
297		break;
298	case ERESTART:
299		framep->tf_regs[FRAME_PC] -= 4;
300		break;
301	case EJUSTRETURN:
302		break;
303	default:
304	bad:
305		error = native_to_linux_errno[error];
306		framep->tf_regs[FRAME_V0] = error;
307		framep->tf_regs[FRAME_A3] = 1;
308		break;
309	}
310
311	trace_exit(code, rval, error);
312
313	userret(l);
314}
315