Commit | Line | Data |
---|---|---|
aec5e0e1 PM |
1 | /* |
2 | * arch/sh/kernel/process.c | |
1da177e4 | 3 | * |
aec5e0e1 | 4 | * This file handles the architecture-dependent parts of process handling.. |
1da177e4 LT |
5 | * |
6 | * Copyright (C) 1995 Linus Torvalds | |
7 | * | |
8 | * SuperH version: Copyright (C) 1999, 2000 Niibe Yutaka & Kaz Kojima | |
8ae91b9a | 9 | * Copyright (C) 2006 Lineo Solutions Inc. support SH4A UBC |
3a2e117e | 10 | * Copyright (C) 2002 - 2007 Paul Mundt |
1da177e4 | 11 | */ |
1da177e4 | 12 | #include <linux/module.h> |
1da177e4 LT |
13 | #include <linux/mm.h> |
14 | #include <linux/elfcore.h> | |
a3310bbd | 15 | #include <linux/pm.h> |
1da177e4 | 16 | #include <linux/kallsyms.h> |
a3310bbd | 17 | #include <linux/kexec.h> |
b118ca57 | 18 | #include <linux/kdebug.h> |
57be2b48 | 19 | #include <linux/tick.h> |
e08f457c | 20 | #include <linux/reboot.h> |
e06c4e57 | 21 | #include <linux/fs.h> |
995bb781 | 22 | #include <linux/preempt.h> |
1da177e4 LT |
23 | #include <asm/uaccess.h> |
24 | #include <asm/mmu_context.h> | |
5f8c9908 | 25 | #include <asm/pgalloc.h> |
bd079997 | 26 | #include <asm/system.h> |
b5233d07 | 27 | #include <asm/ubc.h> |
1da177e4 | 28 | |
aec5e0e1 | 29 | static int hlt_counter; |
1da177e4 LT |
30 | int ubc_usercnt = 0; |
31 | ||
a3310bbd | 32 | void (*pm_idle)(void); |
a3310bbd PM |
33 | void (*pm_power_off)(void); |
34 | EXPORT_SYMBOL(pm_power_off); | |
35 | ||
1da177e4 LT |
36 | void disable_hlt(void) |
37 | { | |
38 | hlt_counter++; | |
39 | } | |
1da177e4 LT |
40 | EXPORT_SYMBOL(disable_hlt); |
41 | ||
42 | void enable_hlt(void) | |
43 | { | |
44 | hlt_counter--; | |
45 | } | |
1da177e4 LT |
46 | EXPORT_SYMBOL(enable_hlt); |
47 | ||
f3a9022f PM |
48 | static int __init nohlt_setup(char *__unused) |
49 | { | |
50 | hlt_counter = 1; | |
51 | return 1; | |
52 | } | |
53 | __setup("nohlt", nohlt_setup); | |
54 | ||
55 | static int __init hlt_setup(char *__unused) | |
56 | { | |
57 | hlt_counter = 0; | |
58 | return 1; | |
59 | } | |
60 | __setup("hlt", hlt_setup); | |
61 | ||
a3310bbd PM |
62 | void default_idle(void) |
63 | { | |
f3a9022f PM |
64 | if (!hlt_counter) { |
65 | clear_thread_flag(TIF_POLLING_NRFLAG); | |
66 | smp_mb__after_clear_bit(); | |
67 | set_bl_bit(); | |
68 | while (!need_resched()) | |
69 | cpu_sleep(); | |
70 | clear_bl_bit(); | |
71 | set_thread_flag(TIF_POLLING_NRFLAG); | |
72 | } else | |
73 | while (!need_resched()) | |
74 | cpu_relax(); | |
a3310bbd PM |
75 | } |
76 | ||
64c7c8f8 | 77 | void cpu_idle(void) |
1da177e4 | 78 | { |
f3a9022f PM |
79 | set_thread_flag(TIF_POLLING_NRFLAG); |
80 | ||
1da177e4 LT |
81 | /* endless idle loop with no priority at all */ |
82 | while (1) { | |
a3310bbd PM |
83 | void (*idle)(void) = pm_idle; |
84 | ||
85 | if (!idle) | |
86 | idle = default_idle; | |
87 | ||
57be2b48 | 88 | tick_nohz_stop_sched_tick(); |
a3310bbd PM |
89 | while (!need_resched()) |
90 | idle(); | |
57be2b48 | 91 | tick_nohz_restart_sched_tick(); |
1da177e4 | 92 | |
5bfb5d69 | 93 | preempt_enable_no_resched(); |
1da177e4 | 94 | schedule(); |
5bfb5d69 | 95 | preempt_disable(); |
5f8c9908 | 96 | check_pgt_cache(); |
1da177e4 LT |
97 | } |
98 | } | |
99 | ||
1da177e4 LT |
100 | void machine_restart(char * __unused) |
101 | { | |
102 | /* SR.BL=1 and invoke address error to let CPU reset (manual reset) */ | |
103 | asm volatile("ldc %0, sr\n\t" | |
104 | "mov.l @%1, %0" : : "r" (0x10000000), "r" (0x80000001)); | |
105 | } | |
106 | ||
1da177e4 LT |
107 | void machine_halt(void) |
108 | { | |
a3310bbd | 109 | local_irq_disable(); |
1da177e4 | 110 | |
1da177e4 LT |
111 | while (1) |
112 | cpu_sleep(); | |
113 | } | |
114 | ||
1da177e4 LT |
115 | void machine_power_off(void) |
116 | { | |
a3310bbd PM |
117 | if (pm_power_off) |
118 | pm_power_off(); | |
1da177e4 LT |
119 | } |
120 | ||
1da177e4 LT |
121 | void show_regs(struct pt_regs * regs) |
122 | { | |
123 | printk("\n"); | |
19c5870c | 124 | printk("Pid : %d, Comm: %20s\n", task_pid_nr(current), current->comm); |
6b002230 | 125 | print_symbol("PC is at %s\n", instruction_pointer(regs)); |
1da177e4 LT |
126 | printk("PC : %08lx SP : %08lx SR : %08lx ", |
127 | regs->pc, regs->regs[15], regs->sr); | |
128 | #ifdef CONFIG_MMU | |
129 | printk("TEA : %08x ", ctrl_inl(MMU_TEA)); | |
130 | #else | |
131 | printk(" "); | |
132 | #endif | |
133 | printk("%s\n", print_tainted()); | |
134 | ||
135 | printk("R0 : %08lx R1 : %08lx R2 : %08lx R3 : %08lx\n", | |
136 | regs->regs[0],regs->regs[1], | |
137 | regs->regs[2],regs->regs[3]); | |
138 | printk("R4 : %08lx R5 : %08lx R6 : %08lx R7 : %08lx\n", | |
139 | regs->regs[4],regs->regs[5], | |
140 | regs->regs[6],regs->regs[7]); | |
141 | printk("R8 : %08lx R9 : %08lx R10 : %08lx R11 : %08lx\n", | |
142 | regs->regs[8],regs->regs[9], | |
143 | regs->regs[10],regs->regs[11]); | |
144 | printk("R12 : %08lx R13 : %08lx R14 : %08lx\n", | |
145 | regs->regs[12],regs->regs[13], | |
146 | regs->regs[14]); | |
147 | printk("MACH: %08lx MACL: %08lx GBR : %08lx PR : %08lx\n", | |
148 | regs->mach, regs->macl, regs->gbr, regs->pr); | |
149 | ||
6b002230 | 150 | show_trace(NULL, (unsigned long *)regs->regs[15], regs); |
1da177e4 LT |
151 | } |
152 | ||
153 | /* | |
154 | * Create a kernel thread | |
155 | */ | |
156 | ||
157 | /* | |
158 | * This is the mechanism for creating a new kernel thread. | |
159 | * | |
160 | */ | |
161 | extern void kernel_thread_helper(void); | |
162 | __asm__(".align 5\n" | |
163 | "kernel_thread_helper:\n\t" | |
164 | "jsr @r5\n\t" | |
165 | " nop\n\t" | |
166 | "mov.l 1f, r1\n\t" | |
167 | "jsr @r1\n\t" | |
168 | " mov r0, r4\n\t" | |
169 | ".align 2\n\t" | |
170 | "1:.long do_exit"); | |
171 | ||
aec5e0e1 | 172 | /* Don't use this in BL=1(cli). Or else, CPU resets! */ |
1da177e4 | 173 | int kernel_thread(int (*fn)(void *), void * arg, unsigned long flags) |
aec5e0e1 | 174 | { |
1da177e4 LT |
175 | struct pt_regs regs; |
176 | ||
177 | memset(®s, 0, sizeof(regs)); | |
aec5e0e1 PM |
178 | regs.regs[4] = (unsigned long)arg; |
179 | regs.regs[5] = (unsigned long)fn; | |
1da177e4 | 180 | |
aec5e0e1 | 181 | regs.pc = (unsigned long)kernel_thread_helper; |
1da177e4 LT |
182 | regs.sr = (1 << 30); |
183 | ||
184 | /* Ok, create the new process.. */ | |
aec5e0e1 PM |
185 | return do_fork(flags | CLONE_VM | CLONE_UNTRACED, 0, |
186 | ®s, 0, NULL, NULL); | |
1da177e4 LT |
187 | } |
188 | ||
189 | /* | |
190 | * Free current thread data structures etc.. | |
191 | */ | |
192 | void exit_thread(void) | |
193 | { | |
194 | if (current->thread.ubc_pc) { | |
195 | current->thread.ubc_pc = 0; | |
196 | ubc_usercnt -= 1; | |
197 | } | |
198 | } | |
199 | ||
200 | void flush_thread(void) | |
201 | { | |
202 | #if defined(CONFIG_SH_FPU) | |
203 | struct task_struct *tsk = current; | |
1da177e4 | 204 | /* Forget lazy FPU state */ |
3cf0f4ec | 205 | clear_fpu(tsk, task_pt_regs(tsk)); |
1da177e4 LT |
206 | clear_used_math(); |
207 | #endif | |
208 | } | |
209 | ||
210 | void release_thread(struct task_struct *dead_task) | |
211 | { | |
212 | /* do nothing */ | |
213 | } | |
214 | ||
215 | /* Fill in the fpu structure for a core dump.. */ | |
216 | int dump_fpu(struct pt_regs *regs, elf_fpregset_t *fpu) | |
217 | { | |
218 | int fpvalid = 0; | |
219 | ||
220 | #if defined(CONFIG_SH_FPU) | |
221 | struct task_struct *tsk = current; | |
222 | ||
223 | fpvalid = !!tsk_used_math(tsk); | |
224 | if (fpvalid) { | |
225 | unlazy_fpu(tsk, regs); | |
226 | memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu)); | |
227 | } | |
228 | #endif | |
229 | ||
230 | return fpvalid; | |
231 | } | |
232 | ||
aec5e0e1 | 233 | /* |
1da177e4 LT |
234 | * Capture the user space registers if the task is not running (in user space) |
235 | */ | |
236 | int dump_task_regs(struct task_struct *tsk, elf_gregset_t *regs) | |
237 | { | |
238 | struct pt_regs ptregs; | |
aec5e0e1 | 239 | |
3cf0f4ec | 240 | ptregs = *task_pt_regs(tsk); |
1da177e4 LT |
241 | elf_core_copy_regs(regs, &ptregs); |
242 | ||
243 | return 1; | |
244 | } | |
245 | ||
aec5e0e1 | 246 | int dump_task_fpu(struct task_struct *tsk, elf_fpregset_t *fpu) |
1da177e4 LT |
247 | { |
248 | int fpvalid = 0; | |
249 | ||
250 | #if defined(CONFIG_SH_FPU) | |
251 | fpvalid = !!tsk_used_math(tsk); | |
252 | if (fpvalid) { | |
3cf0f4ec | 253 | unlazy_fpu(tsk, task_pt_regs(tsk)); |
1da177e4 LT |
254 | memcpy(fpu, &tsk->thread.fpu.hard, sizeof(*fpu)); |
255 | } | |
256 | #endif | |
257 | ||
258 | return fpvalid; | |
259 | } | |
260 | ||
261 | asmlinkage void ret_from_fork(void); | |
262 | ||
263 | int copy_thread(int nr, unsigned long clone_flags, unsigned long usp, | |
264 | unsigned long unused, | |
265 | struct task_struct *p, struct pt_regs *regs) | |
266 | { | |
2991be72 | 267 | struct thread_info *ti = task_thread_info(p); |
1da177e4 LT |
268 | struct pt_regs *childregs; |
269 | #if defined(CONFIG_SH_FPU) | |
270 | struct task_struct *tsk = current; | |
271 | ||
272 | unlazy_fpu(tsk, regs); | |
273 | p->thread.fpu = tsk->thread.fpu; | |
274 | copy_to_stopped_child_used_math(p); | |
275 | #endif | |
276 | ||
3cf0f4ec | 277 | childregs = task_pt_regs(p); |
1da177e4 LT |
278 | *childregs = *regs; |
279 | ||
280 | if (user_mode(regs)) { | |
281 | childregs->regs[15] = usp; | |
2991be72 | 282 | ti->addr_limit = USER_DS; |
1da177e4 | 283 | } else { |
e6bcf562 | 284 | childregs->regs[15] = (unsigned long)childregs; |
2991be72 | 285 | ti->addr_limit = KERNEL_DS; |
1da177e4 | 286 | } |
aec5e0e1 | 287 | |
e6bcf562 | 288 | if (clone_flags & CLONE_SETTLS) |
1da177e4 | 289 | childregs->gbr = childregs->regs[0]; |
aec5e0e1 | 290 | |
1da177e4 LT |
291 | childregs->regs[0] = 0; /* Set return value for child */ |
292 | ||
293 | p->thread.sp = (unsigned long) childregs; | |
294 | p->thread.pc = (unsigned long) ret_from_fork; | |
295 | ||
296 | p->thread.ubc_pc = 0; | |
297 | ||
298 | return 0; | |
299 | } | |
300 | ||
1da177e4 | 301 | /* Tracing by user break controller. */ |
aec5e0e1 | 302 | static void ubc_set_tracing(int asid, unsigned long pc) |
1da177e4 | 303 | { |
8ae91b9a RS |
304 | #if defined(CONFIG_CPU_SH4A) |
305 | unsigned long val; | |
306 | ||
307 | val = (UBC_CBR_ID_INST | UBC_CBR_RW_READ | UBC_CBR_CE); | |
308 | val |= (UBC_CBR_AIE | UBC_CBR_AIV_SET(asid)); | |
309 | ||
310 | ctrl_outl(val, UBC_CBR0); | |
311 | ctrl_outl(pc, UBC_CAR0); | |
312 | ctrl_outl(0x0, UBC_CAMR0); | |
313 | ctrl_outl(0x0, UBC_CBCR); | |
314 | ||
315 | val = (UBC_CRR_RES | UBC_CRR_PCB | UBC_CRR_BIE); | |
316 | ctrl_outl(val, UBC_CRR0); | |
317 | ||
aec5e0e1 | 318 | /* Read UBC register that we wrote last, for checking update */ |
8ae91b9a RS |
319 | val = ctrl_inl(UBC_CRR0); |
320 | ||
321 | #else /* CONFIG_CPU_SH4A */ | |
1da177e4 LT |
322 | ctrl_outl(pc, UBC_BARA); |
323 | ||
a2d1a5fa | 324 | #ifdef CONFIG_MMU |
357d5946 | 325 | ctrl_outb(asid, UBC_BASRA); |
a2d1a5fa | 326 | #endif |
1da177e4 LT |
327 | |
328 | ctrl_outl(0, UBC_BAMRA); | |
329 | ||
11c19656 | 330 | if (current_cpu_data.type == CPU_SH7729 || |
3a2e117e PM |
331 | current_cpu_data.type == CPU_SH7710 || |
332 | current_cpu_data.type == CPU_SH7712) { | |
1da177e4 LT |
333 | ctrl_outw(BBR_INST | BBR_READ | BBR_CPU, UBC_BBRA); |
334 | ctrl_outl(BRCR_PCBA | BRCR_PCTE, UBC_BRCR); | |
335 | } else { | |
336 | ctrl_outw(BBR_INST | BBR_READ, UBC_BBRA); | |
337 | ctrl_outw(BRCR_PCBA, UBC_BRCR); | |
338 | } | |
8ae91b9a | 339 | #endif /* CONFIG_CPU_SH4A */ |
1da177e4 LT |
340 | } |
341 | ||
342 | /* | |
343 | * switch_to(x,y) should switch tasks from x to y. | |
344 | * | |
345 | */ | |
aec5e0e1 PM |
346 | struct task_struct *__switch_to(struct task_struct *prev, |
347 | struct task_struct *next) | |
1da177e4 LT |
348 | { |
349 | #if defined(CONFIG_SH_FPU) | |
3cf0f4ec | 350 | unlazy_fpu(prev, task_pt_regs(prev)); |
1da177e4 LT |
351 | #endif |
352 | ||
83662461 | 353 | #if defined(CONFIG_GUSA) && defined(CONFIG_PREEMPT) |
1da177e4 | 354 | { |
1da177e4 LT |
355 | struct pt_regs *regs; |
356 | ||
995bb781 | 357 | preempt_disable(); |
3cf0f4ec | 358 | regs = task_pt_regs(prev); |
1da177e4 LT |
359 | if (user_mode(regs) && regs->regs[15] >= 0xc0000000) { |
360 | int offset = (int)regs->regs[15]; | |
361 | ||
362 | /* Reset stack pointer: clear critical region mark */ | |
363 | regs->regs[15] = regs->regs[1]; | |
364 | if (regs->pc < regs->regs[0]) | |
365 | /* Go to rewind point */ | |
366 | regs->pc = regs->regs[0] + offset; | |
367 | } | |
995bb781 | 368 | preempt_enable_no_resched(); |
1da177e4 LT |
369 | } |
370 | #endif | |
371 | ||
a2d1a5fa | 372 | #ifdef CONFIG_MMU |
1da177e4 LT |
373 | /* |
374 | * Restore the kernel mode register | |
aec5e0e1 | 375 | * k7 (r7_bank1) |
1da177e4 LT |
376 | */ |
377 | asm volatile("ldc %0, r7_bank" | |
378 | : /* no output */ | |
cafcfcaa | 379 | : "r" (task_thread_info(next))); |
a2d1a5fa | 380 | #endif |
1da177e4 | 381 | |
1da177e4 LT |
382 | /* If no tasks are using the UBC, we're done */ |
383 | if (ubc_usercnt == 0) | |
384 | /* If no tasks are using the UBC, we're done */; | |
385 | else if (next->thread.ubc_pc && next->mm) { | |
a2d1a5fa YS |
386 | int asid = 0; |
387 | #ifdef CONFIG_MMU | |
aec5e0e1 | 388 | asid |= cpu_asid(smp_processor_id(), next->mm); |
a2d1a5fa YS |
389 | #endif |
390 | ubc_set_tracing(asid, next->thread.ubc_pc); | |
1da177e4 | 391 | } else { |
8ae91b9a RS |
392 | #if defined(CONFIG_CPU_SH4A) |
393 | ctrl_outl(UBC_CBR_INIT, UBC_CBR0); | |
394 | ctrl_outl(UBC_CRR_INIT, UBC_CRR0); | |
395 | #else | |
1da177e4 LT |
396 | ctrl_outw(0, UBC_BBRA); |
397 | ctrl_outw(0, UBC_BBRB); | |
8ae91b9a | 398 | #endif |
1da177e4 | 399 | } |
1da177e4 LT |
400 | |
401 | return prev; | |
402 | } | |
403 | ||
404 | asmlinkage int sys_fork(unsigned long r4, unsigned long r5, | |
405 | unsigned long r6, unsigned long r7, | |
f0bc814c | 406 | struct pt_regs __regs) |
1da177e4 LT |
407 | { |
408 | #ifdef CONFIG_MMU | |
882c12c4 | 409 | struct pt_regs *regs = RELOC_HIDE(&__regs, 0); |
f0bc814c | 410 | return do_fork(SIGCHLD, regs->regs[15], regs, 0, NULL, NULL); |
1da177e4 LT |
411 | #else |
412 | /* fork almost works, enough to trick you into looking elsewhere :-( */ | |
413 | return -EINVAL; | |
414 | #endif | |
415 | } | |
416 | ||
417 | asmlinkage int sys_clone(unsigned long clone_flags, unsigned long newsp, | |
418 | unsigned long parent_tidptr, | |
419 | unsigned long child_tidptr, | |
f0bc814c | 420 | struct pt_regs __regs) |
1da177e4 | 421 | { |
f0bc814c | 422 | struct pt_regs *regs = RELOC_HIDE(&__regs, 0); |
1da177e4 | 423 | if (!newsp) |
f0bc814c SM |
424 | newsp = regs->regs[15]; |
425 | return do_fork(clone_flags, newsp, regs, 0, | |
aec5e0e1 PM |
426 | (int __user *)parent_tidptr, |
427 | (int __user *)child_tidptr); | |
1da177e4 LT |
428 | } |
429 | ||
430 | /* | |
431 | * This is trivial, and on the face of it looks like it | |
432 | * could equally well be done in user mode. | |
433 | * | |
434 | * Not so, for quite unobvious reasons - register pressure. | |
435 | * In user mode vfork() cannot have a stack frame, and if | |
436 | * done by calling the "clone()" system call directly, you | |
437 | * do not have enough call-clobbered registers to hold all | |
438 | * the information you need. | |
439 | */ | |
440 | asmlinkage int sys_vfork(unsigned long r4, unsigned long r5, | |
441 | unsigned long r6, unsigned long r7, | |
f0bc814c | 442 | struct pt_regs __regs) |
1da177e4 | 443 | { |
f0bc814c SM |
444 | struct pt_regs *regs = RELOC_HIDE(&__regs, 0); |
445 | return do_fork(CLONE_VFORK | CLONE_VM | SIGCHLD, regs->regs[15], regs, | |
1da177e4 LT |
446 | 0, NULL, NULL); |
447 | } | |
448 | ||
449 | /* | |
450 | * sys_execve() executes a new program. | |
451 | */ | |
e08f457c PM |
452 | asmlinkage int sys_execve(char __user *ufilename, char __user * __user *uargv, |
453 | char __user * __user *uenvp, unsigned long r7, | |
f0bc814c | 454 | struct pt_regs __regs) |
1da177e4 | 455 | { |
f0bc814c | 456 | struct pt_regs *regs = RELOC_HIDE(&__regs, 0); |
1da177e4 LT |
457 | int error; |
458 | char *filename; | |
459 | ||
e08f457c | 460 | filename = getname(ufilename); |
1da177e4 LT |
461 | error = PTR_ERR(filename); |
462 | if (IS_ERR(filename)) | |
463 | goto out; | |
464 | ||
e08f457c | 465 | error = do_execve(filename, uargv, uenvp, regs); |
1da177e4 LT |
466 | if (error == 0) { |
467 | task_lock(current); | |
468 | current->ptrace &= ~PT_DTRACE; | |
469 | task_unlock(current); | |
470 | } | |
471 | putname(filename); | |
472 | out: | |
473 | return error; | |
474 | } | |
475 | ||
476 | unsigned long get_wchan(struct task_struct *p) | |
477 | { | |
1da177e4 LT |
478 | unsigned long pc; |
479 | ||
480 | if (!p || p == current || p->state == TASK_RUNNING) | |
481 | return 0; | |
482 | ||
483 | /* | |
484 | * The same comment as on the Alpha applies here, too ... | |
485 | */ | |
486 | pc = thread_saved_pc(p); | |
c64ac9f0 DM |
487 | |
488 | #ifdef CONFIG_FRAME_POINTER | |
1da177e4 | 489 | if (in_sched_functions(pc)) { |
c64ac9f0 | 490 | unsigned long schedule_frame = (unsigned long)p->thread.sp; |
b652c23c | 491 | return ((unsigned long *)schedule_frame)[21]; |
1da177e4 | 492 | } |
c64ac9f0 | 493 | #endif |
b652c23c | 494 | |
1da177e4 LT |
495 | return pc; |
496 | } | |
497 | ||
f0bc814c | 498 | asmlinkage void break_point_trap(void) |
1da177e4 LT |
499 | { |
500 | /* Clear tracing. */ | |
8ae91b9a RS |
501 | #if defined(CONFIG_CPU_SH4A) |
502 | ctrl_outl(UBC_CBR_INIT, UBC_CBR0); | |
503 | ctrl_outl(UBC_CRR_INIT, UBC_CRR0); | |
504 | #else | |
1da177e4 LT |
505 | ctrl_outw(0, UBC_BBRA); |
506 | ctrl_outw(0, UBC_BBRB); | |
8ae91b9a | 507 | #endif |
1da177e4 LT |
508 | current->thread.ubc_pc = 0; |
509 | ubc_usercnt -= 1; | |
510 | ||
511 | force_sig(SIGTRAP, current); | |
512 | } | |
513 | ||
f413d0d9 PM |
514 | /* |
515 | * Generic trap handler. | |
516 | */ | |
517 | asmlinkage void debug_trap_handler(unsigned long r4, unsigned long r5, | |
518 | unsigned long r6, unsigned long r7, | |
519 | struct pt_regs __regs) | |
520 | { | |
521 | struct pt_regs *regs = RELOC_HIDE(&__regs, 0); | |
522 | ||
523 | /* Rewind */ | |
53f983a9 | 524 | regs->pc -= instruction_size(ctrl_inw(regs->pc - 4)); |
f413d0d9 | 525 | |
b118ca57 | 526 | if (notify_die(DIE_TRAP, "debug trap", regs, 0, regs->tra & 0xff, |
3a2e117e PM |
527 | SIGTRAP) == NOTIFY_STOP) |
528 | return; | |
529 | ||
f413d0d9 PM |
530 | force_sig(SIGTRAP, current); |
531 | } | |
532 | ||
533 | /* | |
534 | * Special handler for BUG() traps. | |
535 | */ | |
536 | asmlinkage void bug_trap_handler(unsigned long r4, unsigned long r5, | |
537 | unsigned long r6, unsigned long r7, | |
538 | struct pt_regs __regs) | |
1da177e4 | 539 | { |
f0bc814c SM |
540 | struct pt_regs *regs = RELOC_HIDE(&__regs, 0); |
541 | ||
dc34d312 | 542 | /* Rewind */ |
53f983a9 | 543 | regs->pc -= instruction_size(ctrl_inw(regs->pc - 4)); |
dc34d312 | 544 | |
b118ca57 | 545 | if (notify_die(DIE_TRAP, "bug trap", regs, 0, TRAPA_BUG_OPCODE & 0xff, |
3a2e117e PM |
546 | SIGTRAP) == NOTIFY_STOP) |
547 | return; | |
548 | ||
dc34d312 PM |
549 | #ifdef CONFIG_BUG |
550 | if (__kernel_text_address(instruction_pointer(regs))) { | |
551 | u16 insn = *(u16 *)instruction_pointer(regs); | |
552 | if (insn == TRAPA_BUG_OPCODE) | |
553 | handle_BUG(regs); | |
554 | } | |
555 | #endif | |
556 | ||
1da177e4 LT |
557 | force_sig(SIGTRAP, current); |
558 | } |