1 /* $NetBSD: linux_machdep.c,v 1.52 2021/09/07 11:43:03 riastradh Exp $ */
2
3 /*-
4 * Copyright (c) 1998 The NetBSD Foundation, Inc.
5 * All rights reserved.
6 *
7 * This code is derived from software contributed to The NetBSD Foundation
8 * by Eric Haszlakiewicz.
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 * Based on sys/arch/i386/i386/linux_machdep.c:
32 * linux_machdep.c,v 1.42 1998/09/11 12:50:06 mycroft Exp
33 * written by Frank van der Linden
34 *
35 */
36
37 #include <sys/cdefs.h>
38 __KERNEL_RCSID(0, "$NetBSD: linux_machdep.c,v 1.52 2021/09/07 11:43:03 riastradh Exp $");
39
40 #include <sys/param.h>
41 #include <sys/systm.h>
42 #include <sys/signalvar.h>
43 #include <sys/kernel.h>
44 #include <sys/proc.h>
45 #include <sys/buf.h>
46 #include <sys/reboot.h>
47 #include <sys/conf.h>
48 #include <sys/exec.h>
49 #include <sys/file.h>
50 #include <sys/callout.h>
51 #include <sys/mbuf.h>
52 #include <sys/msgbuf.h>
53 #include <sys/mount.h>
54 #include <sys/vnode.h>
55 #include <sys/device.h>
56 #include <sys/syscallargs.h>
57 #include <sys/filedesc.h>
58 #include <sys/exec_elf.h>
59 #include <sys/ioctl.h>
60 #include <sys/kauth.h>
61
62 #include <uvm/uvm_extern.h>
63
64 #include <compat/linux/common/linux_types.h>
65 #include <compat/linux/common/linux_signal.h>
66 #include <compat/linux/common/linux_siginfo.h>
67 #include <compat/linux/common/linux_util.h>
68 #include <compat/linux/common/linux_ioctl.h>
69 #include <compat/linux/common/linux_exec.h>
70 #include <compat/linux/common/linux_machdep.h>
71 #include <compat/linux/common/linux_emuldata.h>
72
73 #include <compat/linux/linux_syscallargs.h>
74
75 #include <machine/alpha.h>
76 #include <machine/reg.h>
77
78 #if defined(_KERNEL_OPT)
79 #include "wsdisplay.h"
80 #endif
81 #if (NWSDISPLAY >0)
82 #include <dev/wscons/wsdisplay_usl_io.h>
83 #endif
84 #ifdef DEBUG
85 #include <machine/sigdebug.h>
86 #endif
87
88 /*
89 * Deal with some alpha-specific things in the Linux emulation code.
90 */
91
92 void
linux_setregs(struct lwp * l,struct exec_package * epp,vaddr_t stack)93 linux_setregs(struct lwp *l, struct exec_package *epp, vaddr_t stack)
94 {
95 #ifdef DEBUG
96 struct trapframe *tfp = l->l_md.md_tf;
97 #endif
98
99 setregs(l, epp, stack);
100 #ifdef DEBUG
101 /*
102 * Linux has registers set to zero on entry; for DEBUG kernels
103 * the alpha setregs() fills registers with 0xbabefacedeadbeef.
104 */
105 memset(tfp->tf_regs, 0, FRAME_SIZE * sizeof tfp->tf_regs[0]);
106 #endif
107 }
108
109 void
setup_linux_rt_sigframe(struct trapframe * tf,const ksiginfo_t * ksi,const sigset_t * mask)110 setup_linux_rt_sigframe(struct trapframe *tf, const ksiginfo_t *ksi,
111 const sigset_t *mask)
112 {
113 struct lwp *l = curlwp;
114 struct proc *p = l->l_proc;
115 struct linux_rt_sigframe *sfp, sigframe;
116 int onstack, error;
117 int fsize, rndfsize;
118 int sig = ksi->ksi_signo;
119 extern char linux_rt_sigcode[], linux_rt_esigcode[];
120
121 /* Do we need to jump onto the signal stack? */
122 onstack = (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
123 (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
124
125 /* Allocate space for the signal handler context. */
126 fsize = sizeof(struct linux_rt_sigframe);
127 rndfsize = ((fsize + 15) / 16) * 16;
128
129 if (onstack)
130 sfp = (struct linux_rt_sigframe *)
131 ((char *)l->l_sigstk.ss_sp + l->l_sigstk.ss_size);
132 else
133 sfp = (struct linux_rt_sigframe *)(alpha_pal_rdusp());
134 sfp = (struct linux_rt_sigframe *)((char *)sfp - rndfsize);
135
136 #ifdef DEBUG
137 if ((sigdebug & SDB_KSTACK) && (p->p_pid == sigpid))
138 printf("linux_sendsig(%d): sig %d ssp %p usp %p\n", p->p_pid,
139 sig, &onstack, sfp);
140 #endif /* DEBUG */
141
142 memset(&sigframe, 0, sizeof(sigframe));
143
144 /*
145 * Build the signal context to be used by sigreturn.
146 */
147 memset(&sigframe.uc, 0, sizeof(struct linux_ucontext));
148 sigframe.uc.uc_mcontext.sc_onstack = onstack;
149
150 /* Setup potentially partial signal mask in sc_mask. */
151 /* But get all of it in uc_sigmask */
152 native_to_linux_old_sigset(&sigframe.uc.uc_mcontext.sc_mask, mask);
153 native_to_linux_sigset(&sigframe.uc.uc_sigmask, mask);
154
155 sigframe.uc.uc_mcontext.sc_pc = tf->tf_regs[FRAME_PC];
156 sigframe.uc.uc_mcontext.sc_ps = ALPHA_PSL_USERMODE;
157 frametoreg(tf, (struct reg *)sigframe.uc.uc_mcontext.sc_regs);
158 sigframe.uc.uc_mcontext.sc_regs[R_SP] = alpha_pal_rdusp();
159
160 fpu_load();
161 alpha_pal_wrfen(1);
162 sigframe.uc.uc_mcontext.sc_fpcr = alpha_read_fpcr();
163 sigframe.uc.uc_mcontext.sc_fp_control = alpha_read_fp_c(l);
164 alpha_pal_wrfen(0);
165
166 sigframe.uc.uc_mcontext.sc_traparg_a0 = tf->tf_regs[FRAME_A0];
167 sigframe.uc.uc_mcontext.sc_traparg_a1 = tf->tf_regs[FRAME_A1];
168 sigframe.uc.uc_mcontext.sc_traparg_a2 = tf->tf_regs[FRAME_A2];
169 native_to_linux_siginfo(&sigframe.info, &ksi->ksi_info);
170 sendsig_reset(l, sig);
171 mutex_exit(p->p_lock);
172 error = copyout((void *)&sigframe, (void *)sfp, fsize);
173 mutex_enter(p->p_lock);
174
175 if (error != 0) {
176 #ifdef DEBUG
177 if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
178 printf("sendsig(%d): copyout failed on sig %d\n",
179 p->p_pid, sig);
180 #endif
181 /*
182 * Process has trashed its stack; give it an illegal
183 * instruction to halt it in its tracks.
184 */
185 sigexit(l, SIGILL);
186 /* NOTREACHED */
187 }
188
189 /* Pass pointers to siginfo and ucontext in the regs */
190 tf->tf_regs[FRAME_A1] = (unsigned long)&sfp->info;
191 tf->tf_regs[FRAME_A2] = (unsigned long)&sfp->uc;
192
193 /* Address of trampoline code. End up at this PC after mi_switch */
194 tf->tf_regs[FRAME_PC] =
195 (u_int64_t)(p->p_psstrp - (linux_rt_esigcode - linux_rt_sigcode));
196
197 /* Adjust the stack */
198 alpha_pal_wrusp((unsigned long)sfp);
199
200 /* Remember that we're now on the signal stack. */
201 if (onstack)
202 l->l_sigstk.ss_flags |= SS_ONSTACK;
203 }
204
setup_linux_sigframe(struct trapframe * tf,const ksiginfo_t * ksi,const sigset_t * mask)205 void setup_linux_sigframe(struct trapframe *tf, const ksiginfo_t *ksi,
206 const sigset_t *mask)
207 {
208 struct lwp *l = curlwp;
209 struct proc *p = l->l_proc;
210 struct linux_sigframe *sfp, sigframe;
211 int onstack, error;
212 int fsize, rndfsize;
213 int sig = ksi->ksi_signo;
214 extern char linux_sigcode[], linux_esigcode[];
215
216 /* Do we need to jump onto the signal stack? */
217 onstack = (l->l_sigstk.ss_flags & (SS_DISABLE | SS_ONSTACK)) == 0 &&
218 (SIGACTION(p, sig).sa_flags & SA_ONSTACK) != 0;
219
220 /* Allocate space for the signal handler context. */
221 fsize = sizeof(struct linux_sigframe);
222 rndfsize = ((fsize + 15) / 16) * 16;
223
224 if (onstack)
225 sfp = (struct linux_sigframe *)
226 ((char *)l->l_sigstk.ss_sp + l->l_sigstk.ss_size);
227 else
228 sfp = (struct linux_sigframe *)(alpha_pal_rdusp());
229 sfp = (struct linux_sigframe *)((char *)sfp - rndfsize);
230
231 #ifdef DEBUG
232 if ((sigdebug & SDB_KSTACK) && (p->p_pid == sigpid))
233 printf("linux_sendsig(%d): sig %d ssp %p usp %p\n", p->p_pid,
234 sig, &onstack, sfp);
235 #endif /* DEBUG */
236
237 memset(&sigframe, 0, sizeof(sigframe));
238
239 /*
240 * Build the signal context to be used by sigreturn.
241 */
242 memset(&sigframe.sf_sc, 0, sizeof(struct linux_sigcontext));
243 sigframe.sf_sc.sc_onstack = onstack;
244 native_to_linux_old_sigset(&sigframe.sf_sc.sc_mask, mask);
245 sigframe.sf_sc.sc_pc = tf->tf_regs[FRAME_PC];
246 sigframe.sf_sc.sc_ps = ALPHA_PSL_USERMODE;
247 frametoreg(tf, (struct reg *)sigframe.sf_sc.sc_regs);
248 sigframe.sf_sc.sc_regs[R_SP] = alpha_pal_rdusp();
249
250 if (fpu_valid_p(l)) {
251 struct pcb *pcb = lwp_getpcb(l);
252
253 fpu_save(l);
254 sigframe.sf_sc.sc_fpcr = pcb->pcb_fp.fpr_cr;
255 }
256 /* XXX ownedfp ? etc...? */
257
258 sigframe.sf_sc.sc_traparg_a0 = tf->tf_regs[FRAME_A0];
259 sigframe.sf_sc.sc_traparg_a1 = tf->tf_regs[FRAME_A1];
260 sigframe.sf_sc.sc_traparg_a2 = tf->tf_regs[FRAME_A2];
261
262 sendsig_reset(l, sig);
263 mutex_exit(p->p_lock);
264 error = copyout((void *)&sigframe, (void *)sfp, fsize);
265 mutex_enter(p->p_lock);
266
267 if (error != 0) {
268 #ifdef DEBUG
269 if ((sigdebug & SDB_KSTACK) && p->p_pid == sigpid)
270 printf("sendsig(%d): copyout failed on sig %d\n",
271 p->p_pid, sig);
272 #endif
273 /*
274 * Process has trashed its stack; give it an illegal
275 * instruction to halt it in its tracks.
276 */
277 sigexit(l, SIGILL);
278 /* NOTREACHED */
279 }
280
281 /* Pass pointers to sigcontext in the regs */
282 tf->tf_regs[FRAME_A1] = 0;
283 tf->tf_regs[FRAME_A2] = (unsigned long)&sfp->sf_sc;
284
285 /* Address of trampoline code. End up at this PC after mi_switch */
286 tf->tf_regs[FRAME_PC] =
287 (u_int64_t)(p->p_psstrp - (linux_esigcode - linux_sigcode));
288
289 /* Adjust the stack */
290 alpha_pal_wrusp((unsigned long)sfp);
291
292 /* Remember that we're now on the signal stack. */
293 if (onstack)
294 l->l_sigstk.ss_flags |= SS_ONSTACK;
295 }
296
297 /*
298 * Send an interrupt to process.
299 *
300 * Stack is set up to allow sigcode stored
301 * in u. to call routine, followed by kcall
302 * to sigreturn routine below. After sigreturn
303 * resets the signal mask, the stack, and the
304 * frame pointer, it returns to the user
305 * specified pc, psl.
306 */
307 void
linux_sendsig(const ksiginfo_t * ksi,const sigset_t * mask)308 linux_sendsig(const ksiginfo_t *ksi, const sigset_t *mask)
309 {
310 struct lwp *l = curlwp;
311 struct proc *p = l->l_proc;
312 struct trapframe *tf = l->l_md.md_tf;
313 const int sig = ksi->ksi_signo;
314 sig_t catcher = SIGACTION(p, sig).sa_handler;
315 #ifdef notyet
316 struct linux_emuldata *edp;
317
318 /* Setup the signal frame (and part of the trapframe) */
319 /*OLD: if (p->p_sigacts->ps_siginfo & sigmask(sig))*/
320 /* XXX XAX this is broken now. need someplace to store what
321 XXX XAX kind of signal handler a signal has.*/
322 #if 0
323 edp = (struct linux_emuldata *)p->p_emuldata;
324 #else
325 edp = 0;
326 #endif
327 if (edp && sigismember(&edp->ps_siginfo, sig))
328 setup_linux_rt_sigframe(tf, ksi, mask);
329 else
330 #endif /* notyet */
331 setup_linux_sigframe(tf, ksi, mask);
332
333 /* Signal handler for trampoline code */
334 tf->tf_regs[FRAME_T12] = (u_int64_t)catcher;
335 tf->tf_regs[FRAME_A0] = native_to_linux_signo[sig];
336
337 /*
338 * Linux has a custom restorer option. To support it we would
339 * need to store an array of restorers and a sigcode block
340 * which knew to use it. Doesn't seem worth the trouble.
341 * -erh
342 */
343
344 #ifdef DEBUG
345 if (sigdebug & SDB_FOLLOW)
346 printf("sendsig(%d): pc %lx, catcher %lx\n", l->l_proc->p_pid,
347 tf->tf_regs[FRAME_PC], tf->tf_regs[FRAME_A3]);
348 if ((sigdebug & SDB_KSTACK) && l->l_proc->p_pid == sigpid)
349 printf("sendsig(%d): sig %d returns\n", l->l_proc->p_pid, sig);
350 #endif
351 }
352
353 /*
354 * System call to cleanup state after a signal
355 * has been taken. Reset signal mask and
356 * stack state from context left by sendsig (above).
357 * Return to previous pc as specified by context
358 * left by sendsig.
359 * Linux real-time signals use a different sigframe,
360 * but the sigcontext is the same.
361 */
362
363 int
linux_restore_sigcontext(struct lwp * l,struct linux_sigcontext context,sigset_t * mask)364 linux_restore_sigcontext(struct lwp *l, struct linux_sigcontext context,
365 sigset_t *mask)
366 {
367 struct proc *p = l->l_proc;
368 struct pcb *pcb;
369
370 /*
371 * Linux doesn't (yet) have alternate signal stacks.
372 * However, the OSF/1 sigcontext which they use has
373 * an onstack member. This could be needed in the future.
374 */
375 mutex_enter(p->p_lock);
376 if (context.sc_onstack & LINUX_SA_ONSTACK)
377 l->l_sigstk.ss_flags |= SS_ONSTACK;
378 else
379 l->l_sigstk.ss_flags &= ~SS_ONSTACK;
380
381 /* Reset the signal mask */
382 (void) sigprocmask1(l, SIG_SETMASK, mask, 0);
383 mutex_exit(p->p_lock);
384
385 /*
386 * Check for security violations.
387 * Linux doesn't allow any changes to the PSL.
388 */
389 if (context.sc_ps != ALPHA_PSL_USERMODE)
390 return(EINVAL);
391
392 l->l_md.md_tf->tf_regs[FRAME_PC] = context.sc_pc;
393 l->l_md.md_tf->tf_regs[FRAME_PS] = context.sc_ps;
394
395 regtoframe((struct reg *)context.sc_regs, l->l_md.md_tf);
396 alpha_pal_wrusp(context.sc_regs[R_SP]);
397
398 /* Restore fp regs and fpr_cr */
399 pcb = lwp_getpcb(l);
400 memcpy(&pcb->pcb_fp, (struct fpreg *)context.sc_fpregs,
401 sizeof(struct fpreg));
402 /* XXX sc_ownedfp ? */
403 /* XXX sc_fp_control ? */
404
405 #ifdef DEBUG
406 if (sigdebug & SDB_FOLLOW)
407 printf("linux_rt_sigreturn(%d): returns\n", p->p_pid);
408 #endif
409 return (EJUSTRETURN);
410 }
411
412 int
linux_sys_rt_sigreturn(struct lwp * l,const struct linux_sys_rt_sigreturn_args * uap,register_t * retval)413 linux_sys_rt_sigreturn(struct lwp *l, const struct linux_sys_rt_sigreturn_args *uap, register_t *retval)
414 {
415 /* {
416 syscallarg(struct linux_rt_sigframe *) sfp;
417 } */
418 struct linux_rt_sigframe *sfp, sigframe;
419 sigset_t mask;
420
421 /*
422 * The trampoline code hands us the context.
423 * It is unsafe to keep track of it ourselves, in the event that a
424 * program jumps out of a signal handler.
425 */
426
427 sfp = SCARG(uap, sfp);
428
429 if (ALIGN(sfp) != (u_int64_t)sfp)
430 return(EINVAL);
431
432 /*
433 * Fetch the frame structure.
434 */
435 if (copyin((void *)sfp, &sigframe,
436 sizeof(struct linux_rt_sigframe)) != 0)
437 return (EFAULT);
438
439 /* Grab the signal mask */
440 linux_to_native_sigset(&mask, &sigframe.uc.uc_sigmask);
441
442 return(linux_restore_sigcontext(l, sigframe.uc.uc_mcontext, &mask));
443 }
444
445
446 int
linux_sys_sigreturn(struct lwp * l,const struct linux_sys_sigreturn_args * uap,register_t * retval)447 linux_sys_sigreturn(struct lwp *l, const struct linux_sys_sigreturn_args *uap, register_t *retval)
448 {
449 /* {
450 syscallarg(struct linux_sigframe *) sfp;
451 } */
452 struct linux_sigframe *sfp, frame;
453 sigset_t mask;
454
455 /*
456 * The trampoline code hands us the context.
457 * It is unsafe to keep track of it ourselves, in the event that a
458 * program jumps out of a signal handler.
459 */
460
461 sfp = SCARG(uap, sfp);
462 if (ALIGN(sfp) != (u_int64_t)sfp)
463 return(EINVAL);
464
465 /*
466 * Fetch the frame structure.
467 */
468 if (copyin((void *)sfp, &frame, sizeof(struct linux_sigframe)) != 0)
469 return(EFAULT);
470
471 /* Grab the signal mask. */
472 /* XXX use frame.extramask */
473 linux_old_to_native_sigset(&mask, frame.sf_sc.sc_mask);
474
475 return(linux_restore_sigcontext(l, frame.sf_sc, &mask));
476 }
477
478 /*
479 * We come here in a last attempt to satisfy a Linux ioctl() call
480 */
481 /* XXX XAX update this, add maps, etc... */
482 int
linux_machdepioctl(struct lwp * l,const struct linux_sys_ioctl_args * uap,register_t * retval)483 linux_machdepioctl(struct lwp *l, const struct linux_sys_ioctl_args *uap, register_t *retval)
484 {
485 /* {
486 syscallarg(int) fd;
487 syscallarg(u_long) com;
488 syscallarg(void *) data;
489 } */
490 struct sys_ioctl_args bia;
491 u_long com;
492
493 SCARG(&bia, fd) = SCARG(uap, fd);
494 SCARG(&bia, data) = SCARG(uap, data);
495 com = SCARG(uap, com);
496
497 switch (com) {
498 default:
499 printf("linux_machdepioctl: invalid ioctl %08lx\n", com);
500 return EINVAL;
501 }
502 SCARG(&bia, com) = com;
503 return sys_ioctl(l, &bia, retval);
504 }
505
506 /* XXX XAX fix this */
507 dev_t
linux_fakedev(dev_t dev,int raw)508 linux_fakedev(dev_t dev, int raw)
509 {
510 return dev;
511 }
512
513 int
linux_usertrap(struct lwp * l,vaddr_t trapaddr,void * arg)514 linux_usertrap(struct lwp *l, vaddr_t trapaddr, void *arg)
515 {
516 return 0;
517 }
518