sig_machdep.c revision 1.27 
1/*	$NetBSD: sig_machdep.c,v 1.27 2007/02/09 21:55:11 ad Exp $	*/
2
3/*
4 * Copyright (C) 1995, 1996 Wolfgang Solfrank.
5 * Copyright (C) 1995, 1996 TooLs GmbH.
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 *    notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 *    notice, this list of conditions and the following disclaimer in the
15 *    documentation and/or other materials provided with the distribution.
16 * 3. All advertising materials mentioning features or use of this software
17 *    must display the following acknowledgement:
18 *	This product includes software developed by TooLs GmbH.
19 * 4. The name of TooLs GmbH may not be used to endorse or promote products
20 *    derived from this software without specific prior written permission.
21 *
22 * THIS SOFTWARE IS PROVIDED BY TOOLS GMBH ``AS IS'' AND ANY EXPRESS OR
23 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
24 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
25 * IN NO EVENT SHALL TOOLS GMBH BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
26 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
27 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
28 * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
29 * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
30 * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
31 * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
32 */
33
34#include <sys/cdefs.h>
35__KERNEL_RCSID(0, "$NetBSD: sig_machdep.c,v 1.27 2007/02/09 21:55:11 ad Exp $");
36
37#include "opt_compat_netbsd.h"
38#include "opt_ppcarch.h"
39#include "opt_altivec.h"
40
41#include <sys/param.h>
42#include <sys/mount.h>
43#include <sys/proc.h>
44#include <sys/syscallargs.h>
45#include <sys/systm.h>
46#include <sys/ucontext.h>
47#include <sys/user.h>
48
49#include <powerpc/fpu.h>
50#include <powerpc/altivec.h>
51
52/*
53 * Send a signal to process.
54 */
55void
56sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
57{
58	struct lwp * const l = curlwp;
59	struct proc * const p = l->l_proc;
60	struct trapframe * const tf = trapframe(l);
61	struct sigaltstack *ss = &l->l_sigstk;
62	const struct sigact_sigdesc *sd =
63	    &p->p_sigacts->sa_sigdesc[ksi->ksi_signo];
64	ucontext_t uc;
65	vaddr_t sp, sip, ucp;
66	int onstack, error;
67
68	if (sd->sd_vers < 2) {
69#ifdef COMPAT_16
70		sendsig_sigcontext(ksi->ksi_signo, mask, KSI_TRAPCODE(ksi));
71		return;
72#else
73		goto nosupport;
74#endif
75	}
76
77	/* Do we need to jump onto the signal stack? */
78	onstack = (ss->ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
79	    (sd->sd_sigact.sa_flags & SA_ONSTACK) != 0;
80
81	/* Find top of stack.  */
82	sp = (onstack ? (vaddr_t)ss->ss_sp + ss->ss_size : tf->fixreg[1]);
83	sp &= ~(CALLFRAMELEN-1);
84
85	/* Allocate space for the ucontext.  */
86	sp -= sizeof(ucontext_t);
87	ucp = sp;
88
89	/* Allocate space for the siginfo.  */
90	sp -= sizeof(siginfo_t);
91	sip = sp;
92
93	sp &= ~(CALLFRAMELEN-1);
94
95	/* Save register context. */
96	uc.uc_flags = _UC_SIGMASK;
97	uc.uc_sigmask = *mask;
98	uc.uc_link = NULL;
99	memset(&uc.uc_stack, 0, sizeof(uc.uc_stack));
100	sendsig_reset(l, ksi->ksi_signo);
101	mutex_exit(&p->p_smutex);
102	cpu_getmcontext(l, &uc.uc_mcontext, &uc.uc_flags);
103
104	/*
105	 * Copy the siginfo and ucontext onto the user's stack.
106	 */
107	error = (copyout(&ksi->ksi_info, (caddr_t)sip, sizeof(ksi->ksi_info)) != 0 ||
108	    copyout(&uc, (caddr_t)ucp, sizeof(uc)) != 0);
109	mutex_exit(&p->p_smutex);
110
111	if (error) {
112		/*
113		 * Process has trashed its stack; give it an illegal
114		 * instruction to halt it in its tracks.
115		 */
116		sigexit(l, SIGILL);
117		/* NOTREACHED */
118	}
119
120	/*
121	 * Build context to run handler in.  Note the trampoline version
122	 * numbers are coordinated with machine-dependent code in libc.
123	 */
124	switch (sd->sd_vers) {
125	case 2:		/* siginfo sigtramp */
126		tf->fixreg[1]  = (register_t)sp - CALLFRAMELEN;
127		tf->fixreg[3]  = (register_t)ksi->ksi_signo;
128		tf->fixreg[4]  = (register_t)sip;
129		tf->fixreg[5]  = (register_t)ucp;
130		/* Preserve ucp across call to signal function */
131		tf->fixreg[30] = (register_t)ucp;
132		tf->lr         = (register_t)sd->sd_tramp;
133		tf->srr0       = (register_t)sd->sd_sigact.sa_handler;
134		break;
135
136	default:
137		goto nosupport;
138	}
139
140	/* Remember that we're now on the signal stack. */
141	if (onstack)
142		ss->ss_flags |= SS_ONSTACK;
143	return;
144
145 nosupport:
146	/* Don't know what trampoline version; kill it. */
147	printf("sendsig_siginfo(sig %d): bad version %d\n",
148	    ksi->ksi_signo, sd->sd_vers);
149	sigexit(l, SIGILL);
150	/* NOTREACHED */
151}
152
153void
154cpu_getmcontext(struct lwp *l, mcontext_t *mcp, unsigned int *flagp)
155{
156	const struct trapframe *tf = trapframe(l);
157	__greg_t *gr = mcp->__gregs;
158#if defined(PPC_HAVE_FPU) || defined(ALTIVEC)
159	struct pcb *pcb = &l->l_addr->u_pcb;
160#endif
161
162	/* Save GPR context. */
163	(void)memcpy(gr, &tf->fixreg, 32 * sizeof (gr[0])); /* GR0-31 */
164	gr[_REG_CR]  = tf->cr;
165	gr[_REG_LR]  = tf->lr;
166	gr[_REG_PC]  = tf->srr0;
167	gr[_REG_MSR] = tf->srr1 & PSL_USERSRR1;
168#ifdef PPC_HAVE_FPU
169	gr[_REG_MSR] |= pcb->pcb_flags & (PCB_FE0|PCB_FE1);
170#endif
171#ifdef ALTIVEC
172	gr[_REG_MSR] |= pcb->pcb_flags & PCB_ALTIVEC ? PSL_VEC : 0;
173#endif
174	gr[_REG_CTR] = tf->ctr;
175	gr[_REG_XER] = tf->xer;
176#ifdef PPC_OEA
177	gr[_REG_MQ]  = tf->tf_xtra[TF_MQ];
178#else
179	gr[_REG_MQ]  = 0;
180#endif
181	*flagp |= _UC_CPU;
182
183#ifdef PPC_HAVE_FPU
184	/* Save FPR context, if any. */
185	if ((pcb->pcb_flags & PCB_FPU) != 0) {
186		/* If we're the FPU owner, dump its context to the PCB first. */
187		if (pcb->pcb_fpcpu)
188			save_fpu_lwp(l, FPU_SAVE);
189		(void)memcpy(mcp->__fpregs.__fpu_regs, pcb->pcb_fpu.fpreg,
190		    sizeof (mcp->__fpregs.__fpu_regs));
191		mcp->__fpregs.__fpu_fpscr =
192		    ((int *)&pcb->pcb_fpu.fpscr)[_QUAD_LOWWORD];
193		mcp->__fpregs.__fpu_valid = 1;
194		*flagp |= _UC_FPU;
195	} else
196#endif
197		memset(&mcp->__fpregs, 0, sizeof(mcp->__fpregs));
198
199#ifdef ALTIVEC
200	/* Save AltiVec context, if any. */
201	if ((pcb->pcb_flags & PCB_ALTIVEC) != 0) {
202		/*
203		 * If we're the AltiVec owner, dump its context
204		 * to the PCB first.
205		 */
206		if (pcb->pcb_veccpu)
207			save_vec_lwp(l, ALTIVEC_SAVE);
208		(void)memcpy(mcp->__vrf.__vrs, pcb->pcb_vr.vreg,
209		    sizeof (mcp->__vrf.__vrs));
210		mcp->__vrf.__vscr = pcb->pcb_vr.vscr;
211		mcp->__vrf.__vrsave = pcb->pcb_vr.vrsave;
212		*flagp |= _UC_POWERPC_VEC;
213	} else
214#endif
215		memset(&mcp->__vrf, 0, sizeof (mcp->__vrf));
216}
217
218int
219cpu_setmcontext(struct lwp *l, const mcontext_t *mcp, unsigned int flags)
220{
221	struct trapframe *tf = trapframe(l);
222	const __greg_t *gr = mcp->__gregs;
223#ifdef PPC_HAVE_FPU
224	struct pcb *pcb = &l->l_addr->u_pcb;
225#endif
226
227	/* Restore GPR context, if any. */
228	if (flags & _UC_CPU) {
229#ifdef PPC_HAVE_FPU
230		/*
231		 * Always save the FP exception mode in the PCB.
232		 */
233		pcb->pcb_flags &= ~(PCB_FE0|PCB_FE1);
234		pcb->pcb_flags |= gr[_REG_MSR] & (PCB_FE0|PCB_FE1);
235#endif
236
237		(void)memcpy(&tf->fixreg, gr, 32 * sizeof (gr[0]));
238		tf->cr   = gr[_REG_CR];
239		tf->lr   = gr[_REG_LR];
240		tf->srr0 = gr[_REG_PC];
241		/*
242		 * Accept all user-settable bits without complaint;
243		 * userland should not need to know the machine-specific
244		 * MSR value.
245		 */
246		tf->srr1 = (gr[_REG_MSR] & PSL_USERMOD) | PSL_USERSET;
247		tf->ctr  = gr[_REG_CTR];
248		tf->xer  = gr[_REG_XER];
249#ifdef PPC_OEA
250		tf->tf_xtra[TF_MQ] = gr[_REG_MQ];
251#endif
252	}
253
254#ifdef PPC_HAVE_FPU /* Restore FPR context, if any. */
255	if ((flags & _UC_FPU) && mcp->__fpregs.__fpu_valid != 0) {
256		/* we don't need to save the state, just drop it */
257		save_fpu_lwp(l, FPU_DISCARD);
258		(void)memcpy(&pcb->pcb_fpu.fpreg, &mcp->__fpregs.__fpu_regs,
259		    sizeof (pcb->pcb_fpu.fpreg));
260		((int *)&pcb->pcb_fpu.fpscr)[_QUAD_LOWWORD] =
261		    mcp->__fpregs.__fpu_fpscr;
262	}
263#endif
264
265#ifdef ALTIVEC
266	/* Restore AltiVec context, if any. */
267	if (flags & _UC_POWERPC_VEC) {
268		/* we don't need to save the state, just drop it */
269		save_vec_lwp(l, ALTIVEC_DISCARD);
270		(void)memcpy(pcb->pcb_vr.vreg, &mcp->__vrf.__vrs,
271		    sizeof (pcb->pcb_vr.vreg));
272		pcb->pcb_vr.vscr = mcp->__vrf.__vscr;
273		pcb->pcb_vr.vrsave = mcp->__vrf.__vrsave;
274	}
275#endif
276
277	return (0);
278}
279