1 /* $NetBSD: linux_machdep.c,v 1.45 2025/08/10 09:17:59 andvar Exp $ */ 2 3 /*- 4 * Copyright (c) 1995, 2000, 2001 The NetBSD Foundation, Inc. 5 * All rights reserved. 6 * 7 * This code is derived from software contributed to The NetBSD Foundation 8 * by Frank van der Linden and Emmanuel Dreyfus. 9 * 10 * Redistribution and use in source and binary forms, with or without 11 * modification, are permitted provided that the following conditions 12 * are met: 13 * 1. Redistributions of source code must retain the above copyright 14 * notice, this list of conditions and the following disclaimer. 15 * 2. Redistributions in binary form must reproduce the above copyright 16 * notice, this list of conditions and the following disclaimer in the 17 * documentation and/or other materials provided with the distribution. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS 20 * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED 21 * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR 22 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS 23 * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR 24 * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF 25 * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS 26 * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN 27 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) 28 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 29 * POSSIBILITY OF SUCH DAMAGE. 30 */ 31 32 #include <sys/cdefs.h> 33 __KERNEL_RCSID(0, "$NetBSD: linux_machdep.c,v 1.45 2025/08/10 09:17:59 andvar Exp $"); 34 35 #include <sys/param.h> 36 #include <sys/systm.h> 37 #include <sys/signalvar.h> 38 #include <sys/kernel.h> 39 #include <sys/proc.h> 40 #include <sys/buf.h> 41 #include <sys/reboot.h> 42 #include <sys/conf.h> 43 #include <sys/exec.h> 44 #include <sys/file.h> 45 #include <sys/callout.h> 46 #include <sys/mbuf.h> 47 #include <sys/msgbuf.h> 48 #include <sys/mount.h> 49 #include <sys/vnode.h> 50 #include <sys/device.h> 51 #include <sys/syscallargs.h> 52 #include <sys/filedesc.h> 53 #include <sys/exec_elf.h> 54 #include <sys/disklabel.h> 55 #include <sys/ioctl.h> 56 #include <sys/sysctl.h> 57 #include <sys/kauth.h> 58 #include <miscfs/specfs/specdev.h> 59 60 #include <compat/linux/common/linux_types.h> 61 #include <compat/linux/common/linux_signal.h> 62 #include <compat/linux/common/linux_util.h> 63 #include <compat/linux/common/linux_ioctl.h> 64 #include <compat/linux/common/linux_hdio.h> 65 #include <compat/linux/common/linux_exec.h> 66 #include <compat/linux/common/linux_machdep.h> 67 68 #include <compat/linux/linux_syscallargs.h> 69 70 #include <sys/cpu.h> 71 #include <machine/psl.h> 72 #include <machine/reg.h> 73 #include <machine/regnum.h> 74 #include <machine/vmparam.h> 75 #include <machine/locore.h> 76 77 #include <mips/cache.h> 78 79 union linux_ksigframe { 80 struct linux_sigframe sf; 81 #if !defined(__mips_o32) 82 struct linux_sigframe32 sf32; 83 #endif 84 }; 85 86 /* 87 * To see whether wscons is configured (for virtual console ioctl calls). 88 */ 89 #if defined(_KERNEL_OPT) 90 #include "wsdisplay.h" 91 #endif 92 #if (NWSDISPLAY > 0) 93 #include <dev/wscons/wsconsio.h> 94 #include <dev/wscons/wsdisplay_usl_io.h> 95 #endif 96 97 /* 98 * Set set up registers on exec. 99 */ 100 void 101 linux_setregs(struct lwp *l, struct exec_package *pack, vaddr_t stack) 102 { 103 setregs(l, pack, stack); 104 return; 105 } 106 107 #if !defined(__mips_o32) 108 static void 109 linux_setup_sigcontext32(struct linux_sigcontext32 *sc, 110 const struct trapframe *tf) 111 { 112 for (u_int i = 0; i < 32; i++) { 113 sc->lsc_regs[i] = tf->tf_regs[i]; 114 } 115 sc->lsc_mdhi = tf->tf_regs[_R_MULHI]; 116 sc->lsc_mdlo = tf->tf_regs[_R_MULLO]; 117 sc->lsc_pc = tf->tf_regs[_R_PC]; 118 } 119 #endif 120 121 static void 122 linux_setup_sigcontext(struct linux_sigcontext *sc, 123 const struct trapframe *tf) 124 { 125 for (u_int i = 0; i < 32; i++) { 126 sc->lsc_regs[i] = tf->tf_regs[i]; 127 } 128 sc->lsc_mdhi = tf->tf_regs[_R_MULHI]; 129 sc->lsc_mdlo = tf->tf_regs[_R_MULLO]; 130 sc->lsc_pc = tf->tf_regs[_R_PC]; 131 } 132 133 /* 134 * Send an interrupt to process. 135 * 136 * Adapted from sys/arch/mips/mips/mips_machdep.c 137 * 138 * XXX Does not work well yet with RT signals 139 * 140 */ 141 142 void 143 linux_sendsig(const ksiginfo_t *ksi, const sigset_t *mask) 144 { 145 const int sig = ksi->ksi_signo; 146 struct lwp * const l = curlwp; 147 struct proc * const p = l->l_proc; 148 struct trapframe * const tf = l->l_md.md_utf; 149 #ifdef __mips_o32 150 const int abi = _MIPS_BSD_API_O32; 151 #else 152 const int abi = p->p_md.md_abi; 153 #endif 154 union linux_ksigframe ksf, *sf; 155 bool onstack; 156 int error; 157 sig_t catcher = SIGACTION(p, sig).sa_handler; 158 159 #ifdef DEBUG_LINUX 160 printf("linux_sendsig()\n"); 161 #endif /* DEBUG_LINUX */ 162 163 /* 164 * Do we need to jump onto the signal stack? 165 */ 166 onstack = (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 167 && (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0; 168 169 /* 170 * Signal stack is broken (see at the end of linux_sigreturn), so we do 171 * not use it yet. XXX fix this. 172 */ 173 onstack = false; 174 175 /* 176 * Allocate space for the signal handler context. 177 */ 178 sf = (void *)(onstack 179 ? (uintptr_t) l->l_sigstk.ss_sp + l->l_sigstk.ss_size 180 : (uintptr_t) tf->tf_regs[_R_SP]); 181 182 /* 183 * Build stack frame for signal trampoline. 184 */ 185 memset(&ksf, 0, sizeof ksf); 186 187 /* 188 * This is the signal trampoline used by Linux, we don't use it, 189 * but we set it up in case an application expects it to be there 190 */ 191 ksf.sf.lsf_code[0] = 0x24020000; /* li v0, __NR_sigreturn */ 192 ksf.sf.lsf_code[1] = 0x0000000c; /* syscall */ 193 194 switch (abi) { 195 default: 196 native_to_linux_sigset(&ksf.sf.lsf_mask, mask); 197 linux_setup_sigcontext(&ksf.sf.lsf_sc, tf); 198 break; 199 #if !defined(__mips_o32) 200 case _MIPS_BSD_API_O32: 201 native_to_linux_sigset(&ksf.sf32.lsf_mask, mask); 202 linux_setup_sigcontext32(&ksf.sf32.lsf_sc, tf); 203 break; 204 #endif 205 } 206 sendsig_reset(l, sig); 207 208 /* 209 * Save signal stack. XXX broken 210 */ 211 /* kregs.sc_onstack = l->l_sigstk.ss_flags & SS_ONSTACK; */ 212 213 /* 214 * Install the sigframe onto the stack 215 */ 216 sf -= sizeof(*sf); 217 mutex_exit(p->p_lock); 218 error = copyout(&ksf, sf, sizeof(ksf)); 219 mutex_enter(p->p_lock); 220 221 if (error != 0) { 222 /* 223 * Process has trashed its stack; give it an illegal 224 * instruction to halt it in its tracks. 225 */ 226 #ifdef DEBUG_LINUX 227 printf("linux_sendsig: stack trashed\n"); 228 #endif /* DEBUG_LINUX */ 229 sigexit(l, SIGILL); 230 /* NOTREACHED */ 231 } 232 233 /* Set up the registers to return to sigcode. */ 234 tf->tf_regs[_R_A0] = native_to_linux_signo[sig]; 235 tf->tf_regs[_R_A1] = 0; 236 tf->tf_regs[_R_A2] = (intptr_t)&sf->sf.lsf_sc; 237 238 #ifdef DEBUG_LINUX 239 printf("sigcontext is at %p\n", &sf->sf.lsf_sc); 240 #endif /* DEBUG_LINUX */ 241 242 tf->tf_regs[_R_SP] = (intptr_t)sf; 243 /* Signal trampoline code is at base of user stack. */ 244 tf->tf_regs[_R_RA] = (intptr_t)p->p_sigctx.ps_sigcode; 245 tf->tf_regs[_R_T9] = (intptr_t)catcher; 246 tf->tf_regs[_R_PC] = (intptr_t)catcher; 247 248 /* Remember that we're now on the signal stack. */ 249 if (onstack) 250 l->l_sigstk.ss_flags |= SS_ONSTACK; 251 252 return; 253 } 254 255 static void 256 linux_putaway_sigcontext(struct trapframe *tf, 257 const struct linux_sigcontext *sc) 258 { 259 for (u_int i = 0; i < 32; i++) { 260 tf->tf_regs[i] = sc->lsc_regs[i]; 261 } 262 tf->tf_regs[_R_MULLO] = sc->lsc_mdlo; 263 tf->tf_regs[_R_MULHI] = sc->lsc_mdhi; 264 tf->tf_regs[_R_PC] = sc->lsc_pc; 265 } 266 267 #ifndef __mips_o32 268 static void 269 linux_putaway_sigcontext32(struct trapframe *tf, 270 const struct linux_sigcontext32 *sc) 271 { 272 for (u_int i = 0; i < 32; i++) { 273 tf->tf_regs[i] = sc->lsc_regs[i]; 274 } 275 tf->tf_regs[_R_MULLO] = sc->lsc_mdlo; 276 tf->tf_regs[_R_MULHI] = sc->lsc_mdhi; 277 tf->tf_regs[_R_PC] = sc->lsc_pc; 278 } 279 #endif 280 281 /* 282 * System call to cleanup state after a signal 283 * has been taken. Reset signal mask and 284 * stack state from context left by sendsig (above). 285 */ 286 int 287 linux_sys_sigreturn(struct lwp *l, const struct linux_sys_sigreturn_args *uap, register_t *retval) 288 { 289 /* { 290 syscallarg(struct linux_sigframe *) sf; 291 } */ 292 struct proc *p = l->l_proc; 293 union linux_ksigframe ksf, *sf; 294 #ifdef __mips_o32 295 const int abi = _MIPS_BSD_API_O32; 296 #else 297 const int abi = p->p_md.md_abi; 298 #endif 299 linux_sigset_t *lmask; 300 sigset_t mask; 301 int error; 302 303 #ifdef DEBUG_LINUX 304 printf("linux_sys_sigreturn()\n"); 305 #endif /* DEBUG_LINUX */ 306 307 /* 308 * The trampoline code hands us the context. 309 * It is unsafe to keep track of it ourselves, in the event that a 310 * program jumps out of a signal handler. 311 */ 312 sf = (void *)SCARG(uap, sf); 313 314 if ((error = copyin(sf, &ksf, sizeof(ksf))) != 0) 315 return (error); 316 317 /* Restore the register context. */ 318 switch (abi) { 319 default: 320 lmask = &ksf.sf.lsf_mask; 321 linux_putaway_sigcontext(l->l_md.md_utf, &ksf.sf.lsf_sc); 322 break; 323 #if !defined(__mips_o32) 324 case _MIPS_BSD_API_O32: 325 lmask = &ksf.sf32.lsf_mask; 326 linux_putaway_sigcontext32(l->l_md.md_utf, &ksf.sf32.lsf_sc); 327 break; 328 #endif 329 } 330 331 mutex_enter(p->p_lock); 332 333 /* Restore signal stack. */ 334 l->l_sigstk.ss_flags &= ~SS_ONSTACK; 335 336 /* Restore signal mask. */ 337 linux_to_native_sigset(&mask, lmask); 338 (void)sigprocmask1(l, SIG_SETMASK, &mask, 0); 339 340 mutex_exit(p->p_lock); 341 342 return (EJUSTRETURN); 343 } 344 345 346 int 347 linux_sys_rt_sigreturn(struct lwp *l, const struct linux_sys_rt_sigreturn_args *v, register_t *retval) 348 { 349 return (ENOSYS); 350 } 351 352 353 /* 354 * major device numbers remapping 355 */ 356 dev_t 357 linux_fakedev(dev_t dev, int raw) 358 { 359 /* XXX write me */ 360 return dev; 361 } 362 363 /* 364 * We come here in a last attempt to satisfy a Linux ioctl() call 365 */ 366 int 367 linux_machdepioctl(struct lwp *l, const struct linux_sys_ioctl_args *uap, register_t *retval) 368 { 369 return 0; 370 } 371 372 /* 373 * See above. If a root process tries to set access to an I/O port, 374 * just let it have the whole range. 375 */ 376 int 377 linux_sys_ioperm(struct lwp *l, const struct linux_sys_ioperm_args *uap, register_t *retval) 378 { 379 /* 380 * This syscall is not implemented in Linux/Mips: we should not be here 381 */ 382 #ifdef DEBUG_LINUX 383 printf("linux_sys_ioperm: should not be here.\n"); 384 #endif /* DEBUG_LINUX */ 385 return 0; 386 } 387 388 /* 389 * wrapper linux_sys_new_uname() -> linux_sys_uname() 390 */ 391 int 392 linux_sys_new_uname(struct lwp *l, const struct linux_sys_new_uname_args *uap, register_t *retval) 393 { 394 /* 395 * Use this if you want to try Linux emulation with a glibc-2.2 396 * or higher. Note that signals will not work 397 */ 398 #if 0 399 struct linux_sys_uname_args /* { 400 syscallarg(struct linux_utsname *) up; 401 } */ *uap = v; 402 struct linux_utsname luts; 403 404 memset(&luts, 0, sizeof(luts)); 405 strlcpy(luts.l_sysname, linux_sysname, sizeof(luts.l_sysname)); 406 strlcpy(luts.l_nodename, hostname, sizeof(luts.l_nodename)); 407 strlcpy(luts.l_release, "2.4.0", sizeof(luts.l_release)); 408 strlcpy(luts.l_version, linux_version, sizeof(luts.l_version)); 409 strlcpy(luts.l_machine, machine, sizeof(luts.l_machine)); 410 strlcpy(luts.l_domainname, domainname, sizeof(luts.l_domainname)); 411 412 return copyout(&luts, SCARG(uap, up), sizeof(luts)); 413 #else 414 return linux_sys_uname(l, (const void *)uap, retval); 415 #endif 416 } 417 418 /* 419 * In Linux, cacheflush is currently implemented 420 * as a whole cache flush (arguments are ignored) 421 * we emulate this broken beahior. 422 */ 423 int 424 linux_sys_cacheflush(struct lwp *l, const struct linux_sys_cacheflush_args *uap, register_t *retval) 425 { 426 mips_icache_sync_all(); 427 mips_dcache_wbinv_all(); 428 return 0; 429 } 430 431 /* 432 * This system call is depecated in Linux, but 433 * some binaries and some libraries use it. 434 */ 435 int 436 linux_sys_sysmips(struct lwp *l, const struct linux_sys_sysmips_args *uap, register_t *retval) 437 { 438 /* { 439 syscallarg(long) cmd; 440 syscallarg(long) arg1; 441 syscallarg(long) arg2; 442 syscallarg(long) arg3; 443 } */ 444 int error; 445 446 switch (SCARG(uap, cmd)) { 447 case LINUX_SETNAME: { 448 char nodename [LINUX___NEW_UTS_LEN + 1]; 449 int name[2]; 450 size_t len; 451 452 if ((error = copyinstr((char *)SCARG(uap, arg1), nodename, 453 LINUX___NEW_UTS_LEN, &len)) != 0) 454 return error; 455 456 name[0] = CTL_KERN; 457 name[1] = KERN_HOSTNAME; 458 return (old_sysctl(&name[0], 2, 0, 0, nodename, len, NULL)); 459 460 break; 461 } 462 case LINUX_MIPS_ATOMIC_SET: { 463 void *addr; 464 int s; 465 u_int8_t value = 0; 466 467 addr = (void *)SCARG(uap, arg1); 468 469 s = splhigh(); 470 /* 471 * No error testing here. This is bad, but Linux does 472 * it like this. The source acknowledge "This is broken" 473 * in a comment... 474 */ 475 (void) copyin(addr, &value, 1); 476 *retval = value; 477 value = (u_int8_t) SCARG(uap, arg2); 478 error = copyout(&value, addr, 1); 479 splx(s); 480 481 return 0; 482 break; 483 } 484 case LINUX_MIPS_FIXADE: /* XXX not implemented */ 485 break; 486 case LINUX_FLUSH_CACHE: 487 mips_icache_sync_all(); 488 mips_dcache_wbinv_all(); 489 break; 490 case LINUX_MIPS_RDNVRAM: 491 return EIO; 492 break; 493 default: 494 return EINVAL; 495 break; 496 } 497 #ifdef DEBUG_LINUX 498 printf("linux_sys_sysmips(): unimplemented command %d\n", 499 SCARG(uap,cmd)); 500 #endif /* DEBUG_LINUX */ 501 return 0; 502 } 503 504 int 505 linux_usertrap(struct lwp *l, vaddr_t trapaddr, void *arg) 506 { 507 return 0; 508 } 509 510 int 511 linux_sys_set_thread_area(struct lwp *l, const struct linux_sys_set_thread_area_args *uap, register_t *retval) 512 { 513 /* { 514 syscallarg(void *) tls; 515 } */ 516 517 return lwp_setprivate(l, SCARG(uap, tls)); 518 } 519
Indexes created Sun Sep 21 20:09:37 GMT 2025