1 /* $NetBSD: sig_machdep.c,v 1.55 2023/12/20 15:29:06 thorpej 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 1.55 2023/12/20 15:29:06 thorpej Exp $"); 36 37 #ifdef _KERNEL_OPT 38 #include "opt_altivec.h" 39 #include "opt_ppcarch.h" 40 #endif 41 42 #include <sys/param.h> 43 #include <sys/mount.h> 44 #include <sys/proc.h> 45 #include <sys/syscallargs.h> 46 #include <sys/systm.h> 47 #include <sys/ucontext.h> 48 #include <sys/cpu.h> 49 50 #include <uvm/uvm_extern.h> 51 52 #include <powerpc/fpu.h> 53 #include <powerpc/altivec.h> 54 #include <powerpc/pcb.h> 55 #include <powerpc/psl.h> 56 57 /* Assert that the sizes of these two structures are multiples of 16. */ 58 CTASSERT((sizeof(siginfo_t) & (CALLFRAMELEN-1)) == 0); 59 CTASSERT((sizeof(ucontext_t) & (CALLFRAMELEN-1)) == 0); 60 61 /* 62 * Send a signal to process. 63 */ 64 void 65 sendsig_siginfo(const ksiginfo_t *ksi, const sigset_t *mask) 66 { 67 struct lwp * const l = curlwp; 68 struct proc * const p = l->l_proc; 69 struct trapframe * const tf = l->l_md.md_utf; 70 stack_t * const ss = &l->l_sigstk; 71 const struct sigact_sigdesc * const sd = 72 &p->p_sigacts->sa_sigdesc[ksi->ksi_signo]; 73 /* save handler before sendsig_reset trashes it! */ 74 const void * const handler = sd->sd_sigact.sa_handler; 75 ucontext_t uc; 76 vaddr_t sp, sip, ucp; 77 int onstack, error; 78 79 /* Do we need to jump onto the signal stack? */ 80 onstack = (ss->ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 && 81 (sd->sd_sigact.sa_flags & SA_ONSTACK) != 0; 82 83 /* Find top of stack. */ 84 sp = (onstack ? (vaddr_t)ss->ss_sp + ss->ss_size : tf->tf_fixreg[1]); 85 86 /* Ensure it is aligned. */ 87 sp &= ~(CALLFRAMELEN-1); 88 89 /* Allocate space for the ucontext. */ 90 sp -= sizeof(ucontext_t); 91 92 /* Allocate space for the siginfo. */ 93 sp -= sizeof(siginfo_t); 94 95 #if 0 /* Not needed; see CTASSERTs above. */ 96 /* Align it again. */ 97 sp &= ~(CALLFRAMELEN-1); 98 #endif 99 100 sip = sp; 101 ucp = sp + sizeof(siginfo_t); 102 103 KASSERT((sip & (CALLFRAMELEN-1)) == 0); 104 KASSERT((ucp & (CALLFRAMELEN-1)) == 0); 105 106 /* 107 * Now allocate space for a call frame, so that there's 108 * space for the ABI-mandated stack linkage area in the 109 * event the signal handler calls a another function. 110 */ 111 sp -= CALLFRAMELEN; 112 113 /* Save register context. */ 114 memset(&uc, 0, sizeof(uc)); 115 uc.uc_flags = _UC_SIGMASK; 116 uc.uc_flags |= (ss->ss_flags & SS_ONSTACK) ? 117 _UC_SETSTACK : _UC_CLRSTACK; 118 uc.uc_sigmask = *mask; 119 uc.uc_link = l->l_ctxlink; 120 sendsig_reset(l, ksi->ksi_signo); 121 mutex_exit(p->p_lock); 122 cpu_getmcontext(l, &uc.uc_mcontext, &uc.uc_flags); 123 124 /* 125 * Copy the siginfo and ucontext onto the user's stack. 126 */ 127 error = (copyout(&ksi->ksi_info, (void *)sip, sizeof(ksi->ksi_info)) != 0 || 128 copyout(&uc, (void *)ucp, sizeof(uc)) != 0); 129 mutex_enter(p->p_lock); 130 131 if (error) { 132 /* 133 * Process has trashed its stack; give it an illegal 134 * instruction to halt it in its tracks. 135 */ 136 sigexit(l, SIGILL); 137 /* NOTREACHED */ 138 } 139 140 /* 141 * Build context to run handler in. Note the trampoline version 142 * numbers are coordinated with machine-dependent code in libc. 143 */ 144 switch (sd->sd_vers) { 145 case __SIGTRAMP_SIGINFO_VERSION: /* siginfo sigtramp */ 146 tf->tf_fixreg[1] = (register_t)sp; 147 tf->tf_fixreg[3] = (register_t)ksi->ksi_signo; 148 tf->tf_fixreg[4] = (register_t)sip; 149 tf->tf_fixreg[5] = (register_t)ucp; 150 /* Preserve ucp across call to signal function */ 151 tf->tf_fixreg[30] = (register_t)ucp; 152 tf->tf_lr = (register_t)sd->sd_tramp; 153 tf->tf_srr0 = (register_t)handler; 154 break; 155 156 default: 157 goto nosupport; 158 } 159 160 /* Remember that we're now on the signal stack. */ 161 if (onstack) 162 ss->ss_flags |= SS_ONSTACK; 163 return; 164 165 nosupport: 166 /* Don't know what trampoline version; kill it. */ 167 printf("sendsig_siginfo(sig %d): bad version %d\n", 168 ksi->ksi_signo, sd->sd_vers); 169 sigexit(l, SIGILL); 170 /* NOTREACHED */ 171 } 172 173 void 174 cpu_getmcontext(struct lwp *l, mcontext_t *mcp, unsigned int *flagp) 175 { 176 const struct trapframe * const tf = l->l_md.md_utf; 177 __greg_t * const gr = mcp->__gregs; 178 #if defined(PPC_HAVE_FPU) 179 struct pcb * const pcb = lwp_getpcb(l); 180 #endif 181 182 /* Save GPR context. */ 183 (void)memcpy(gr, &tf->tf_fixreg, 32 * sizeof (gr[0])); /* GR0-31 */ 184 gr[_REG_CR] = tf->tf_cr; 185 gr[_REG_LR] = tf->tf_lr; 186 gr[_REG_PC] = tf->tf_srr0; 187 gr[_REG_MSR] = tf->tf_srr1 & PSL_USERSRR1; 188 #ifdef PPC_HAVE_FPU 189 gr[_REG_MSR] |= pcb->pcb_flags & (PCB_FE0|PCB_FE1); 190 #endif 191 gr[_REG_CTR] = tf->tf_ctr; 192 gr[_REG_XER] = tf->tf_xer; 193 #ifdef PPC_OEA 194 gr[_REG_MQ] = tf->tf_mq; 195 #else 196 gr[_REG_MQ] = 0; 197 #endif 198 199 *flagp |= _UC_CPU; 200 *flagp |= _UC_TLSBASE; 201 202 #ifdef PPC_HAVE_FPU 203 /* Save FPU context, if any. */ 204 if (!fpu_save_to_mcontext(l, mcp, flagp)) 205 #endif 206 memset(&mcp->__fpregs, 0, sizeof(mcp->__fpregs)); 207 208 #if defined(ALTIVEC) || defined(PPC_HAVE_SPE) 209 /* Save vector context, if any. */ 210 if (!vec_save_to_mcontext(l, mcp, flagp)) 211 #endif 212 memset(&mcp->__vrf, 0, sizeof (mcp->__vrf)); 213 } 214 215 int 216 cpu_mcontext_validate(struct lwp *l, const mcontext_t *mcp) 217 { 218 return 0; 219 } 220 221 int 222 cpu_setmcontext(struct lwp *l, const mcontext_t *mcp, unsigned int flags) 223 { 224 struct trapframe * const tf = l->l_md.md_utf; 225 const __greg_t * const gr = mcp->__gregs; 226 struct proc * const p = l->l_proc; 227 int error; 228 229 /* Restore GPR context, if any. */ 230 if (flags & _UC_CPU) { 231 error = cpu_mcontext_validate(l, mcp); 232 if (error) 233 return error; 234 235 #ifdef PPC_HAVE_FPU 236 /* 237 * Always save the FP exception mode in the PCB. 238 */ 239 struct pcb * const pcb = lwp_getpcb(l); 240 pcb->pcb_flags &= ~(PCB_FE0|PCB_FE1); 241 pcb->pcb_flags |= gr[_REG_MSR] & (PCB_FE0|PCB_FE1); 242 #endif 243 244 /* 245 * R2 is the TLS register so avoid updating it here. 246 */ 247 248 __greg_t save_r2 = tf->tf_fixreg[_REG_R2]; 249 (void)memcpy(&tf->tf_fixreg, gr, 32 * sizeof (gr[0])); 250 tf->tf_fixreg[_REG_R2] = save_r2; 251 tf->tf_cr = gr[_REG_CR]; 252 tf->tf_lr = gr[_REG_LR]; 253 tf->tf_srr0 = gr[_REG_PC]; 254 255 /* 256 * Accept all user-settable bits without complaint; 257 * userland should not need to know the machine-specific 258 * MSR value. 259 */ 260 tf->tf_srr1 = (gr[_REG_MSR] & PSL_USERMOD) | PSL_USERSET; 261 tf->tf_ctr = gr[_REG_CTR]; 262 tf->tf_xer = gr[_REG_XER]; 263 #ifdef PPC_OEA 264 tf->tf_mq = gr[_REG_MQ]; 265 #endif 266 } 267 268 if (flags & _UC_TLSBASE) 269 lwp_setprivate(l, (void *)(uintptr_t)gr[_REG_R2]); 270 271 #ifdef PPC_HAVE_FPU 272 /* Restore FPU context, if any. */ 273 if (flags & _UC_FPU) 274 fpu_restore_from_mcontext(l, mcp); 275 #endif 276 277 #ifdef ALTIVEC 278 /* Restore AltiVec context, if any. */ 279 if (flags & _UC_POWERPC_VEC) 280 vec_restore_from_mcontext(l, mcp); 281 #endif 282 283 #ifdef PPC_HAVE_SPE 284 /* Restore SPE context, if any. */ 285 if (flags & _UC_POWERPC_SPE) 286 vec_restore_from_mcontext(l, mcp); 287 #endif 288 289 mutex_enter(p->p_lock); 290 if (flags & _UC_SETSTACK) 291 l->l_sigstk.ss_flags |= SS_ONSTACK; 292 if (flags & _UC_CLRSTACK) 293 l->l_sigstk.ss_flags &= ~SS_ONSTACK; 294 mutex_exit(p->p_lock); 295 296 return (0); 297 } 298 299 int 300 cpu_lwp_setprivate(lwp_t *l, void *addr) 301 { 302 struct trapframe * const tf = l->l_md.md_utf; 303 304 tf->tf_fixreg[_REG_R2] = (register_t)addr; 305 306 return 0; 307 } 308
Indexes created Sun Oct 25 00:26:45 UTC 2026