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Merge git://git.kernel.org/pub/scm/linux/kernel/git/torvalds/linux-2.6
[wrt350n-kernel.git] / arch / um / os-Linux / skas / process.c
blob9138ccd8510656b745816abde4b6147e93c84d6b
1 /*
2 * Copyright (C) 2002- 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
3 * Licensed under the GPL
4 */
5
6 #include <stdlib.h>
7 #include <unistd.h>
8 #include <sched.h>
9 #include <errno.h>
10 #include <string.h>
11 #include <sys/mman.h>
12 #include <sys/ptrace.h>
13 #include <sys/wait.h>
14 #include <asm/unistd.h>
15 #include "as-layout.h"
16 #include "chan_user.h"
17 #include "kern_constants.h"
18 #include "kern_util.h"
19 #include "mem.h"
20 #include "os.h"
21 #include "process.h"
22 #include "proc_mm.h"
23 #include "ptrace_user.h"
24 #include "registers.h"
25 #include "skas.h"
26 #include "skas_ptrace.h"
27 #include "user.h"
28 #include "sysdep/stub.h"
29
30 int is_skas_winch(int pid, int fd, void *data)
31 {
32 if (pid != getpgrp())
33 return 0;
34
35 register_winch_irq(-1, fd, -1, data, 0);
36 return 1;
37 }
38
39 static int ptrace_dump_regs(int pid)
40 {
41 unsigned long regs[MAX_REG_NR];
42 int i;
43
44 if (ptrace(PTRACE_GETREGS, pid, 0, regs) < 0)
45 return -errno;
46
47 printk(UM_KERN_ERR "Stub registers -\n");
48 for (i = 0; i < ARRAY_SIZE(regs); i++)
49 printk(UM_KERN_ERR "\t%d - %lx\n", i, regs[i]);
50
51 return 0;
52 }
53
54 /*
55 * Signals that are OK to receive in the stub - we'll just continue it.
56 * SIGWINCH will happen when UML is inside a detached screen.
57 */
58 #define STUB_SIG_MASK (1 << SIGVTALRM)
59
60 /* Signals that the stub will finish with - anything else is an error */
61 #define STUB_DONE_MASK (1 << SIGTRAP)
62
63 void wait_stub_done(int pid)
64 {
65 int n, status, err;
66
67 while (1) {
68 CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED | __WALL));
69 if ((n < 0) || !WIFSTOPPED(status))
70 goto bad_wait;
71
72 if (((1 << WSTOPSIG(status)) & STUB_SIG_MASK) == 0)
73 break;
74
75 err = ptrace(PTRACE_CONT, pid, 0, 0);
76 if (err) {
77 printk(UM_KERN_ERR "wait_stub_done : continue failed, "
78 "errno = %d\n", errno);
79 fatal_sigsegv();
80 }
81 }
82
83 if (((1 << WSTOPSIG(status)) & STUB_DONE_MASK) != 0)
84 return;
85
86 bad_wait:
87 err = ptrace_dump_regs(pid);
88 if (err)
89 printk(UM_KERN_ERR "Failed to get registers from stub, "
90 "errno = %d\n", -err);
91 printk(UM_KERN_ERR "wait_stub_done : failed to wait for SIGTRAP, "
92 "pid = %d, n = %d, errno = %d, status = 0x%x\n", pid, n, errno,
93 status);
94 fatal_sigsegv();
95 }
96
97 extern unsigned long current_stub_stack(void);
98
99 void get_skas_faultinfo(int pid, struct faultinfo * fi)
100 {
101 int err;
102
103 if (ptrace_faultinfo) {
104 err = ptrace(PTRACE_FAULTINFO, pid, 0, fi);
105 if (err) {
106 printk(UM_KERN_ERR "get_skas_faultinfo - "
107 "PTRACE_FAULTINFO failed, errno = %d\n", errno);
108 fatal_sigsegv();
109 }
110
111 /* Special handling for i386, which has different structs */
112 if (sizeof(struct ptrace_faultinfo) < sizeof(struct faultinfo))
113 memset((char *)fi + sizeof(struct ptrace_faultinfo), 0,
114 sizeof(struct faultinfo) -
115 sizeof(struct ptrace_faultinfo));
116 }
117 else {
118 <<<<<<< HEAD:arch/um/os-Linux/skas/process.c
119 =======
120 unsigned long fpregs[FP_SIZE];
121
122 err = get_fp_registers(pid, fpregs);
123 if (err < 0) {
124 printk(UM_KERN_ERR "save_fp_registers returned %d\n",
125 err);
126 fatal_sigsegv();
127 }
128 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:arch/um/os-Linux/skas/process.c
129 err = ptrace(PTRACE_CONT, pid, 0, SIGSEGV);
130 if (err) {
131 printk(UM_KERN_ERR "Failed to continue stub, pid = %d, "
132 "errno = %d\n", pid, errno);
133 fatal_sigsegv();
134 }
135 wait_stub_done(pid);
136
137 /*
138 * faultinfo is prepared by the stub-segv-handler at start of
139 * the stub stack page. We just have to copy it.
140 */
141 memcpy(fi, (void *)current_stub_stack(), sizeof(*fi));
142 <<<<<<< HEAD:arch/um/os-Linux/skas/process.c
143 =======
144
145 err = put_fp_registers(pid, fpregs);
146 if (err < 0) {
147 printk(UM_KERN_ERR "put_fp_registers returned %d\n",
148 err);
149 fatal_sigsegv();
150 }
151 >>>>>>> 264e3e889d86e552b4191d69bb60f4f3b383135a:arch/um/os-Linux/skas/process.c
152 }
153 }
154
155 static void handle_segv(int pid, struct uml_pt_regs * regs)
156 {
157 get_skas_faultinfo(pid, &regs->faultinfo);
158 segv(regs->faultinfo, 0, 1, NULL);
159 }
160
161 /*
162 * To use the same value of using_sysemu as the caller, ask it that value
163 * (in local_using_sysemu
164 */
165 static void handle_trap(int pid, struct uml_pt_regs *regs,
166 int local_using_sysemu)
167 {
168 int err, status;
169
170 if ((UPT_IP(regs) >= STUB_START) && (UPT_IP(regs) < STUB_END))
171 fatal_sigsegv();
172
173 /* Mark this as a syscall */
174 UPT_SYSCALL_NR(regs) = PT_SYSCALL_NR(regs->gp);
175
176 if (!local_using_sysemu)
177 {
178 err = ptrace(PTRACE_POKEUSR, pid, PT_SYSCALL_NR_OFFSET,
179 __NR_getpid);
180 if (err < 0) {
181 printk(UM_KERN_ERR "handle_trap - nullifying syscall "
182 "failed, errno = %d\n", errno);
183 fatal_sigsegv();
184 }
185
186 err = ptrace(PTRACE_SYSCALL, pid, 0, 0);
187 if (err < 0) {
188 printk(UM_KERN_ERR "handle_trap - continuing to end of "
189 "syscall failed, errno = %d\n", errno);
190 fatal_sigsegv();
191 }
192
193 CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED | __WALL));
194 if ((err < 0) || !WIFSTOPPED(status) ||
195 (WSTOPSIG(status) != SIGTRAP + 0x80)) {
196 err = ptrace_dump_regs(pid);
197 if (err)
198 printk(UM_KERN_ERR "Failed to get registers "
199 "from process, errno = %d\n", -err);
200 printk(UM_KERN_ERR "handle_trap - failed to wait at "
201 "end of syscall, errno = %d, status = %d\n",
202 errno, status);
203 fatal_sigsegv();
204 }
205 }
206
207 handle_syscall(regs);
208 }
209
210 extern int __syscall_stub_start;
211
212 static int userspace_tramp(void *stack)
213 {
214 void *addr;
215 int err;
216
217 ptrace(PTRACE_TRACEME, 0, 0, 0);
218
219 signal(SIGTERM, SIG_DFL);
220 signal(SIGWINCH, SIG_IGN);
221 err = set_interval();
222 if (err) {
223 printk(UM_KERN_ERR "userspace_tramp - setting timer failed, "
224 "errno = %d\n", err);
225 exit(1);
226 }
227
228 if (!proc_mm) {
229 /*
230 * This has a pte, but it can't be mapped in with the usual
231 * tlb_flush mechanism because this is part of that mechanism
232 */
233 int fd;
234 unsigned long long offset;
235 fd = phys_mapping(to_phys(&__syscall_stub_start), &offset);
236 addr = mmap64((void *) STUB_CODE, UM_KERN_PAGE_SIZE,
237 PROT_EXEC, MAP_FIXED | MAP_PRIVATE, fd, offset);
238 if (addr == MAP_FAILED) {
239 printk(UM_KERN_ERR "mapping mmap stub at 0x%lx failed, "
240 "errno = %d\n", STUB_CODE, errno);
241 exit(1);
242 }
243
244 if (stack != NULL) {
245 fd = phys_mapping(to_phys(stack), &offset);
246 addr = mmap((void *) STUB_DATA,
247 UM_KERN_PAGE_SIZE, PROT_READ | PROT_WRITE,
248 MAP_FIXED | MAP_SHARED, fd, offset);
249 if (addr == MAP_FAILED) {
250 printk(UM_KERN_ERR "mapping segfault stack "
251 "at 0x%lx failed, errno = %d\n",
252 STUB_DATA, errno);
253 exit(1);
254 }
255 }
256 }
257 if (!ptrace_faultinfo && (stack != NULL)) {
258 struct sigaction sa;
259
260 unsigned long v = STUB_CODE +
261 (unsigned long) stub_segv_handler -
262 (unsigned long) &__syscall_stub_start;
263
264 set_sigstack((void *) STUB_DATA, UM_KERN_PAGE_SIZE);
265 sigemptyset(&sa.sa_mask);
266 sa.sa_flags = SA_ONSTACK | SA_NODEFER;
267 sa.sa_handler = (void *) v;
268 sa.sa_restorer = NULL;
269 if (sigaction(SIGSEGV, &sa, NULL) < 0) {
270 printk(UM_KERN_ERR "userspace_tramp - setting SIGSEGV "
271 "handler failed - errno = %d\n", errno);
272 exit(1);
273 }
274 }
275
276 kill(os_getpid(), SIGSTOP);
277 return 0;
278 }
279
280 /* Each element set once, and only accessed by a single processor anyway */
281 #undef NR_CPUS
282 #define NR_CPUS 1
283 int userspace_pid[NR_CPUS];
284
285 int start_userspace(unsigned long stub_stack)
286 {
287 void *stack;
288 unsigned long sp;
289 int pid, status, n, flags, err;
290
291 stack = mmap(NULL, UM_KERN_PAGE_SIZE,
292 PROT_READ | PROT_WRITE | PROT_EXEC,
293 MAP_PRIVATE | MAP_ANONYMOUS, -1, 0);
294 if (stack == MAP_FAILED) {
295 err = -errno;
296 printk(UM_KERN_ERR "start_userspace : mmap failed, "
297 "errno = %d\n", errno);
298 return err;
299 }
300
301 sp = (unsigned long) stack + UM_KERN_PAGE_SIZE - sizeof(void *);
302
303 flags = CLONE_FILES;
304 if (proc_mm)
305 flags |= CLONE_VM;
306 else
307 flags |= SIGCHLD;
308
309 pid = clone(userspace_tramp, (void *) sp, flags, (void *) stub_stack);
310 if (pid < 0) {
311 err = -errno;
312 printk(UM_KERN_ERR "start_userspace : clone failed, "
313 "errno = %d\n", errno);
314 return err;
315 }
316
317 do {
318 CATCH_EINTR(n = waitpid(pid, &status, WUNTRACED | __WALL));
319 if (n < 0) {
320 err = -errno;
321 printk(UM_KERN_ERR "start_userspace : wait failed, "
322 "errno = %d\n", errno);
323 goto out_kill;
324 }
325 } while (WIFSTOPPED(status) && (WSTOPSIG(status) == SIGVTALRM));
326
327 if (!WIFSTOPPED(status) || (WSTOPSIG(status) != SIGSTOP)) {
328 err = -EINVAL;
329 printk(UM_KERN_ERR "start_userspace : expected SIGSTOP, got "
330 "status = %d\n", status);
331 goto out_kill;
332 }
333
334 if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL,
335 (void *) PTRACE_O_TRACESYSGOOD) < 0) {
336 err = -errno;
337 printk(UM_KERN_ERR "start_userspace : PTRACE_OLDSETOPTIONS "
338 "failed, errno = %d\n", errno);
339 goto out_kill;
340 }
341
342 if (munmap(stack, UM_KERN_PAGE_SIZE) < 0) {
343 err = -errno;
344 printk(UM_KERN_ERR "start_userspace : munmap failed, "
345 "errno = %d\n", errno);
346 goto out_kill;
347 }
348
349 return pid;
350
351 out_kill:
352 os_kill_ptraced_process(pid, 1);
353 return err;
354 }
355
356 void userspace(struct uml_pt_regs *regs)
357 {
358 struct itimerval timer;
359 unsigned long long nsecs, now;
360 int err, status, op, pid = userspace_pid[0];
361 /* To prevent races if using_sysemu changes under us.*/
362 int local_using_sysemu;
363
364 if (getitimer(ITIMER_VIRTUAL, &timer))
365 printk(UM_KERN_ERR "Failed to get itimer, errno = %d\n", errno);
366 nsecs = timer.it_value.tv_sec * UM_NSEC_PER_SEC +
367 timer.it_value.tv_usec * UM_NSEC_PER_USEC;
368 nsecs += os_nsecs();
369
370 while (1) {
371 /*
372 * This can legitimately fail if the process loads a
373 * bogus value into a segment register. It will
374 * segfault and PTRACE_GETREGS will read that value
375 * out of the process. However, PTRACE_SETREGS will
376 * fail. In this case, there is nothing to do but
377 * just kill the process.
378 */
379 if (ptrace(PTRACE_SETREGS, pid, 0, regs->gp))
380 fatal_sigsegv();
381
382 /* Now we set local_using_sysemu to be used for one loop */
383 local_using_sysemu = get_using_sysemu();
384
385 op = SELECT_PTRACE_OPERATION(local_using_sysemu,
386 singlestepping(NULL));
387
388 if (ptrace(op, pid, 0, 0)) {
389 printk(UM_KERN_ERR "userspace - ptrace continue "
390 "failed, op = %d, errno = %d\n", op, errno);
391 fatal_sigsegv();
392 }
393
394 CATCH_EINTR(err = waitpid(pid, &status, WUNTRACED | __WALL));
395 if (err < 0) {
396 printk(UM_KERN_ERR "userspace - wait failed, "
397 "errno = %d\n", errno);
398 fatal_sigsegv();
399 }
400
401 regs->is_user = 1;
402 if (ptrace(PTRACE_GETREGS, pid, 0, regs->gp)) {
403 printk(UM_KERN_ERR "userspace - PTRACE_GETREGS failed, "
404 "errno = %d\n", errno);
405 fatal_sigsegv();
406 }
407
408 UPT_SYSCALL_NR(regs) = -1; /* Assume: It's not a syscall */
409
410 if (WIFSTOPPED(status)) {
411 int sig = WSTOPSIG(status);
412 switch (sig) {
413 case SIGSEGV:
414 if (PTRACE_FULL_FAULTINFO ||
415 !ptrace_faultinfo) {
416 get_skas_faultinfo(pid,
417 &regs->faultinfo);
418 (*sig_info[SIGSEGV])(SIGSEGV, regs);
419 }
420 else handle_segv(pid, regs);
421 break;
422 case SIGTRAP + 0x80:
423 handle_trap(pid, regs, local_using_sysemu);
424 break;
425 case SIGTRAP:
426 relay_signal(SIGTRAP, regs);
427 break;
428 case SIGVTALRM:
429 now = os_nsecs();
430 if (now < nsecs)
431 break;
432 block_signals();
433 (*sig_info[sig])(sig, regs);
434 unblock_signals();
435 nsecs = timer.it_value.tv_sec *
436 UM_NSEC_PER_SEC +
437 timer.it_value.tv_usec *
438 UM_NSEC_PER_USEC;
439 nsecs += os_nsecs();
440 break;
441 case SIGIO:
442 case SIGILL:
443 case SIGBUS:
444 case SIGFPE:
445 case SIGWINCH:
446 block_signals();
447 (*sig_info[sig])(sig, regs);
448 unblock_signals();
449 break;
450 default:
451 printk(UM_KERN_ERR "userspace - child stopped "
452 "with signal %d\n", sig);
453 fatal_sigsegv();
454 }
455 pid = userspace_pid[0];
456 interrupt_end();
457
458 /* Avoid -ERESTARTSYS handling in host */
459 if (PT_SYSCALL_NR_OFFSET != PT_SYSCALL_RET_OFFSET)
460 PT_SYSCALL_NR(regs->gp) = -1;
461 }
462 }
463 }
464
465 static unsigned long thread_regs[MAX_REG_NR];
466
467 static int __init init_thread_regs(void)
468 {
469 get_safe_registers(thread_regs);
470 /* Set parent's instruction pointer to start of clone-stub */
471 thread_regs[REGS_IP_INDEX] = STUB_CODE +
472 (unsigned long) stub_clone_handler -
473 (unsigned long) &__syscall_stub_start;
474 thread_regs[REGS_SP_INDEX] = STUB_DATA + UM_KERN_PAGE_SIZE -
475 sizeof(void *);
476 #ifdef __SIGNAL_FRAMESIZE
477 thread_regs[REGS_SP_INDEX] -= __SIGNAL_FRAMESIZE;
478 #endif
479 return 0;
480 }
481
482 __initcall(init_thread_regs);
483
484 int copy_context_skas0(unsigned long new_stack, int pid)
485 {
486 struct timeval tv = { .tv_sec = 0, .tv_usec = UM_USEC_PER_SEC / UM_HZ };
487 int err;
488 unsigned long current_stack = current_stub_stack();
489 struct stub_data *data = (struct stub_data *) current_stack;
490 struct stub_data *child_data = (struct stub_data *) new_stack;
491 unsigned long long new_offset;
492 int new_fd = phys_mapping(to_phys((void *)new_stack), &new_offset);
493
494 /*
495 * prepare offset and fd of child's stack as argument for parent's
496 * and child's mmap2 calls
497 */
498 *data = ((struct stub_data) { .offset = MMAP_OFFSET(new_offset),
499 .fd = new_fd,
500 .timer = ((struct itimerval)
501 { .it_value = tv,
502 .it_interval = tv }) });
503
504 err = ptrace_setregs(pid, thread_regs);
505 if (err < 0) {
506 err = -errno;
507 printk(UM_KERN_ERR "copy_context_skas0 : PTRACE_SETREGS "
508 "failed, pid = %d, errno = %d\n", pid, -err);
509 return err;
510 }
511
512 /* set a well known return code for detection of child write failure */
513 child_data->err = 12345678;
514
515 /*
516 * Wait, until parent has finished its work: read child's pid from
517 * parent's stack, and check, if bad result.
518 */
519 err = ptrace(PTRACE_CONT, pid, 0, 0);
520 if (err) {
521 err = -errno;
522 printk(UM_KERN_ERR "Failed to continue new process, pid = %d, "
523 "errno = %d\n", pid, errno);
524 return err;
525 }
526
527 wait_stub_done(pid);
528
529 pid = data->err;
530 if (pid < 0) {
531 printk(UM_KERN_ERR "copy_context_skas0 - stub-parent reports "
532 "error %d\n", -pid);
533 return pid;
534 }
535
536 /*
537 * Wait, until child has finished too: read child's result from
538 * child's stack and check it.
539 */
540 wait_stub_done(pid);
541 if (child_data->err != STUB_DATA) {
542 printk(UM_KERN_ERR "copy_context_skas0 - stub-child reports "
543 "error %ld\n", child_data->err);
544 err = child_data->err;
545 goto out_kill;
546 }
547
548 if (ptrace(PTRACE_OLDSETOPTIONS, pid, NULL,
549 (void *)PTRACE_O_TRACESYSGOOD) < 0) {
550 err = -errno;
551 printk(UM_KERN_ERR "copy_context_skas0 : PTRACE_OLDSETOPTIONS "
552 "failed, errno = %d\n", errno);
553 goto out_kill;
554 }
555
556 return pid;
557
558 out_kill:
559 os_kill_ptraced_process(pid, 1);
560 return err;
561 }
562
563 /*
564 * This is used only, if stub pages are needed, while proc_mm is
565 * available. Opening /proc/mm creates a new mm_context, which lacks
566 * the stub-pages. Thus, we map them using /proc/mm-fd
567 */
568 int map_stub_pages(int fd, unsigned long code, unsigned long data,
569 unsigned long stack)
570 {
571 struct proc_mm_op mmop;
572 int n;
573 unsigned long long code_offset;
574 int code_fd = phys_mapping(to_phys((void *) &__syscall_stub_start),
575 &code_offset);
576
577 mmop = ((struct proc_mm_op) { .op = MM_MMAP,
578 .u =
579 { .mmap =
580 { .addr = code,
581 .len = UM_KERN_PAGE_SIZE,
582 .prot = PROT_EXEC,
583 .flags = MAP_FIXED | MAP_PRIVATE,
584 .fd = code_fd,
585 .offset = code_offset
586 } } });
587 CATCH_EINTR(n = write(fd, &mmop, sizeof(mmop)));
588 if (n != sizeof(mmop)) {
589 n = errno;
590 printk(UM_KERN_ERR "mmap args - addr = 0x%lx, fd = %d, "
591 "offset = %llx\n", code, code_fd,
592 (unsigned long long) code_offset);
593 printk(UM_KERN_ERR "map_stub_pages : /proc/mm map for code "
594 "failed, err = %d\n", n);
595 return -n;
596 }
597
598 if (stack) {
599 unsigned long long map_offset;
600 int map_fd = phys_mapping(to_phys((void *)stack), &map_offset);
601 mmop = ((struct proc_mm_op)
602 { .op = MM_MMAP,
603 .u =
604 { .mmap =
605 { .addr = data,
606 .len = UM_KERN_PAGE_SIZE,
607 .prot = PROT_READ | PROT_WRITE,
608 .flags = MAP_FIXED | MAP_SHARED,
609 .fd = map_fd,
610 .offset = map_offset
611 } } });
612 CATCH_EINTR(n = write(fd, &mmop, sizeof(mmop)));
613 if (n != sizeof(mmop)) {
614 n = errno;
615 printk(UM_KERN_ERR "map_stub_pages : /proc/mm map for "
616 "data failed, err = %d\n", n);
617 return -n;
618 }
619 }
620
621 return 0;
622 }
623
624 void new_thread(void *stack, jmp_buf *buf, void (*handler)(void))
625 {
626 (*buf)[0].JB_IP = (unsigned long) handler;
627 (*buf)[0].JB_SP = (unsigned long) stack + UM_THREAD_SIZE -
628 sizeof(void *);
629 }
630
631 #define INIT_JMP_NEW_THREAD 0
632 #define INIT_JMP_CALLBACK 1
633 #define INIT_JMP_HALT 2
634 #define INIT_JMP_REBOOT 3
635
636 void switch_threads(jmp_buf *me, jmp_buf *you)
637 {
638 if (UML_SETJMP(me) == 0)
639 UML_LONGJMP(you, 1);
640 }
641
642 static jmp_buf initial_jmpbuf;
643
644 /* XXX Make these percpu */
645 static void (*cb_proc)(void *arg);
646 static void *cb_arg;
647 static jmp_buf *cb_back;
648
649 int start_idle_thread(void *stack, jmp_buf *switch_buf)
650 {
651 int n;
652
653 set_handler(SIGWINCH, (__sighandler_t) sig_handler,
654 SA_ONSTACK | SA_RESTART, SIGUSR1, SIGIO, SIGVTALRM, -1);
655
656 /*
657 * Can't use UML_SETJMP or UML_LONGJMP here because they save
658 * and restore signals, with the possible side-effect of
659 * trying to handle any signals which came when they were
660 * blocked, which can't be done on this stack.
661 * Signals must be blocked when jumping back here and restored
662 * after returning to the jumper.
663 */
664 n = setjmp(initial_jmpbuf);
665 switch (n) {
666 case INIT_JMP_NEW_THREAD:
667 (*switch_buf)[0].JB_IP = (unsigned long) new_thread_handler;
668 (*switch_buf)[0].JB_SP = (unsigned long) stack +
669 UM_THREAD_SIZE - sizeof(void *);
670 break;
671 case INIT_JMP_CALLBACK:
672 (*cb_proc)(cb_arg);
673 longjmp(*cb_back, 1);
674 break;
675 case INIT_JMP_HALT:
676 kmalloc_ok = 0;
677 return 0;
678 case INIT_JMP_REBOOT:
679 kmalloc_ok = 0;
680 return 1;
681 default:
682 printk(UM_KERN_ERR "Bad sigsetjmp return in "
683 "start_idle_thread - %d\n", n);
684 fatal_sigsegv();
685 }
686 longjmp(*switch_buf, 1);
687 }
688
689 void initial_thread_cb_skas(void (*proc)(void *), void *arg)
690 {
691 jmp_buf here;
692
693 cb_proc = proc;
694 cb_arg = arg;
695 cb_back = &here;
696
697 block_signals();
698 if (UML_SETJMP(&here) == 0)
699 UML_LONGJMP(&initial_jmpbuf, INIT_JMP_CALLBACK);
700 unblock_signals();
701
702 cb_proc = NULL;
703 cb_arg = NULL;
704 cb_back = NULL;
705 }
706
707 void halt_skas(void)
708 {
709 block_signals();
710 UML_LONGJMP(&initial_jmpbuf, INIT_JMP_HALT);
711 }
712
713 void reboot_skas(void)
714 {
715 block_signals();
716 UML_LONGJMP(&initial_jmpbuf, INIT_JMP_REBOOT);
717 }
718
719 void __switch_mm(struct mm_id *mm_idp)
720 {
721 int err;
722
723 /* FIXME: need cpu pid in __switch_mm */
724 if (proc_mm) {
725 err = ptrace(PTRACE_SWITCH_MM, userspace_pid[0], 0,
726 mm_idp->u.mm_fd);
727 if (err) {
728 printk(UM_KERN_ERR "__switch_mm - PTRACE_SWITCH_MM "
729 "failed, errno = %d\n", errno);
730 fatal_sigsegv();
731 }
732 }
733 else userspace_pid[0] = mm_idp->u.pid;
734 }
WRT350N Kernel Patches