1 /* $NetBSD: linux_machdep.c,v 1.44 2021/09/07 11:43:04 riastradh 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 1.44 2021/09/07 11:43:04 riastradh 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
linux_setregs(struct lwp * l,struct exec_package * pack,vaddr_t stack)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
linux_setup_sigcontext32(struct linux_sigcontext32 * sc,const struct trapframe * tf)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
linux_setup_sigcontext(struct linux_sigcontext * sc,const struct trapframe * tf)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
linux_sendsig(const ksiginfo_t * ksi,const sigset_t * mask)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
linux_putaway_sigcontext(struct trapframe * tf,const struct linux_sigcontext * sc)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
linux_putaway_sigcontext32(struct trapframe * tf,const struct linux_sigcontext32 * sc)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
linux_sys_sigreturn(struct lwp * l,const struct linux_sys_sigreturn_args * uap,register_t * retval)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
linux_sys_rt_sigreturn(struct lwp * l,const struct linux_sys_rt_sigreturn_args * v,register_t * retval)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
linux_fakedev(dev_t dev,int raw)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
linux_machdepioctl(struct lwp * l,const struct linux_sys_ioctl_args * uap,register_t * retval)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
linux_sys_ioperm(struct lwp * l,const struct linux_sys_ioperm_args * uap,register_t * retval)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
linux_sys_new_uname(struct lwp * l,const struct linux_sys_new_uname_args * uap,register_t * retval)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
linux_sys_cacheflush(struct lwp * l,const struct linux_sys_cacheflush_args * uap,register_t * retval)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
linux_sys_sysmips(struct lwp * l,const struct linux_sys_sysmips_args * uap,register_t * retval)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 aknowledge "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
linux_usertrap(struct lwp * l,vaddr_t trapaddr,void * arg)505 linux_usertrap(struct lwp *l, vaddr_t trapaddr, void *arg)
506 {
507 return 0;
508 }
509
510 int
linux_sys_set_thread_area(struct lwp * l,const struct linux_sys_set_thread_area_args * uap,register_t * retval)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