arch/m32r/kernel/traps.c

   1 /*
   2  *  linux/arch/m32r/kernel/traps.c
   3  *
   4  *  Copyright (C) 2001, 2002  Hirokazu Takata, Hiroyuki Kondo,
   5  *                            Hitoshi Yamamoto
   6  */
   7
   8 /*
   9  * 'traps.c' handles hardware traps and faults after we have saved some
  10  * state in 'entry.S'.
  11  */
  12 #include <linux/init.h>
  13 #include <linux/kernel.h>
  14 #include <linux/kallsyms.h>
  15 #include <linux/stddef.h>
  16 #include <linux/ptrace.h>
  17 #include <linux/mm.h>
  18 #include <asm/page.h>
  19 #include <asm/processor.h>
  20
  21 #include <asm/system.h>
  22 #include <asm/uaccess.h>
  23 #include <asm/io.h>
  24 #include <linux/atomic.h>
  25
  26 #include <asm/smp.h>
  27
  28 #include <linux/module.h>
  29
  30 asmlinkage void alignment_check(void);
  31 asmlinkage void ei_handler(void);
  32 asmlinkage void rie_handler(void);
  33 asmlinkage void debug_trap(void);
  34 asmlinkage void cache_flushing_handler(void);
  35 asmlinkage void ill_trap(void);
  36
  37 #ifdef CONFIG_SMP
  38 extern void smp_reschedule_interrupt(void);
  39 extern void smp_invalidate_interrupt(void);
  40 extern void smp_call_function_interrupt(void);
  41 extern void smp_ipi_timer_interrupt(void);
  42 extern void smp_flush_cache_all_interrupt(void);
  43 extern void smp_call_function_single_interrupt(void);
  44
  45 /*
  46  * for Boot AP function
  47  */
  48 asm (
  49         "       .section .eit_vector4,\"ax\"    \n"
  50         "       .global _AP_RE                  \n"
  51         "       .global startup_AP              \n"
  52         "_AP_RE:                                \n"
  53         "       .fill 32, 4, 0                  \n"
  54         "_AP_EI: bra    startup_AP              \n"
  55         "       .previous                       \n"
  56 );
  57 #endif  /* CONFIG_SMP */
  58
  59 extern unsigned long    eit_vector[];
  60 #define BRA_INSN(func, entry)   \
  61         ((unsigned long)func - (unsigned long)eit_vector - entry*4)/4 \
  62         + 0xff000000UL
  63
  64 static void set_eit_vector_entries(void)
  65 {
  66         extern void default_eit_handler(void);
  67         extern void system_call(void);
  68         extern void pie_handler(void);
  69         extern void ace_handler(void);
  70         extern void tme_handler(void);
  71         extern void _flush_cache_copyback_all(void);
  72
  73         eit_vector[0] = 0xd0c00001; /* seth r0, 0x01 */
  74         eit_vector[1] = BRA_INSN(default_eit_handler, 1);
  75         eit_vector[4] = 0xd0c00010; /* seth r0, 0x10 */
  76         eit_vector[5] = BRA_INSN(default_eit_handler, 5);
  77         eit_vector[8] = BRA_INSN(rie_handler, 8);
  78         eit_vector[12] = BRA_INSN(alignment_check, 12);
  79         eit_vector[16] = BRA_INSN(ill_trap, 16);
  80         eit_vector[17] = BRA_INSN(debug_trap, 17);
  81         eit_vector[18] = BRA_INSN(system_call, 18);
  82         eit_vector[19] = BRA_INSN(ill_trap, 19);
  83         eit_vector[20] = BRA_INSN(ill_trap, 20);
  84         eit_vector[21] = BRA_INSN(ill_trap, 21);
  85         eit_vector[22] = BRA_INSN(ill_trap, 22);
  86         eit_vector[23] = BRA_INSN(ill_trap, 23);
  87         eit_vector[24] = BRA_INSN(ill_trap, 24);
  88         eit_vector[25] = BRA_INSN(ill_trap, 25);
  89         eit_vector[26] = BRA_INSN(ill_trap, 26);
  90         eit_vector[27] = BRA_INSN(ill_trap, 27);
  91         eit_vector[28] = BRA_INSN(cache_flushing_handler, 28);
  92         eit_vector[29] = BRA_INSN(ill_trap, 29);
  93         eit_vector[30] = BRA_INSN(ill_trap, 30);
  94         eit_vector[31] = BRA_INSN(ill_trap, 31);
  95         eit_vector[32] = BRA_INSN(ei_handler, 32);
  96         eit_vector[64] = BRA_INSN(pie_handler, 64);
  97 #ifdef CONFIG_MMU
  98         eit_vector[68] = BRA_INSN(ace_handler, 68);
  99         eit_vector[72] = BRA_INSN(tme_handler, 72);
 100 #endif /* CONFIG_MMU */
 101 #ifdef CONFIG_SMP
 102         eit_vector[184] = (unsigned long)smp_reschedule_interrupt;
 103         eit_vector[185] = (unsigned long)smp_invalidate_interrupt;
 104         eit_vector[186] = (unsigned long)smp_call_function_interrupt;
 105         eit_vector[187] = (unsigned long)smp_ipi_timer_interrupt;
 106         eit_vector[188] = (unsigned long)smp_flush_cache_all_interrupt;
 107         eit_vector[189] = 0;    /* CPU_BOOT_IPI */
 108         eit_vector[190] = (unsigned long)smp_call_function_single_interrupt;
 109         eit_vector[191] = 0;
 110 #endif
 111         _flush_cache_copyback_all();
 112 }
 113
 114 void __init trap_init(void)
 115 {
 116         set_eit_vector_entries();
 117
 118         /*
 119          * Should be a barrier for any external CPU state.
 120          */
 121         cpu_init();
 122 }
 123
 124 static int kstack_depth_to_print = 24;
 125
 126 static void show_trace(struct task_struct *task, unsigned long *stack)
 127 {
 128         unsigned long addr;
 129
 130         if (!stack)
 131                 stack = (unsigned long*)&stack;
 132
 133         printk("Call Trace: ");
 134         while (!kstack_end(stack)) {
 135                 addr = *stack++;
 136                 if (__kernel_text_address(addr)) {
 137                         printk("[<%08lx>] ", addr);
 138                         print_symbol("%s\n", addr);
 139                 }
 140         }
 141         printk("\n");
 142 }
 143
 144 void show_stack(struct task_struct *task, unsigned long *sp)
 145 {
 146         unsigned long  *stack;
 147         int  i;
 148
 149         /*
 150          * debugging aid: "show_stack(NULL);" prints the
 151          * back trace for this cpu.
 152          */
 153
 154         if(sp==NULL) {
 155                 if (task)
 156                         sp = (unsigned long *)task->thread.sp;
 157                 else
 158                         sp=(unsigned long*)&sp;
 159         }
 160
 161         stack = sp;
 162         for(i=0; i < kstack_depth_to_print; i++) {
 163                 if (kstack_end(stack))
 164                         break;
 165                 if (i && ((i % 4) == 0))
 166                         printk("\n       ");
 167                 printk("%08lx ", *stack++);
 168         }
 169         printk("\n");
 170         show_trace(task, sp);
 171 }
 172
 173 void dump_stack(void)
 174 {
 175         unsigned long stack;
 176
 177         show_trace(current, &stack);
 178 }
 179
 180 EXPORT_SYMBOL(dump_stack);
 181
 182 static void show_registers(struct pt_regs *regs)
 183 {
 184         int i = 0;
 185         int in_kernel = 1;
 186         unsigned long sp;
 187
 188         printk("CPU:    %d\n", smp_processor_id());
 189         show_regs(regs);
 190
 191         sp = (unsigned long) (1+regs);
 192         if (user_mode(regs)) {
 193                 in_kernel = 0;
 194                 sp = regs->spu;
 195                 printk("SPU: %08lx\n", sp);
 196         } else {
 197                 printk("SPI: %08lx\n", sp);
 198         }
 199         printk("Process %s (pid: %d, process nr: %d, stackpage=%08lx)",
 200                 current->comm, task_pid_nr(current), 0xffff & i, 4096+(unsigned long)current);
 201
 202         /*
 203          * When in-kernel, we also print out the stack and code at the
 204          * time of the fault..
 205          */
 206         if (in_kernel) {
 207                 printk("\nStack: ");
 208                 show_stack(current, (unsigned long*) sp);
 209
 210                 printk("\nCode: ");
 211                 if (regs->bpc < PAGE_OFFSET)
 212                         goto bad;
 213
 214                 for(i=0;i<20;i++) {
 215                         unsigned char c;
 216                         if (__get_user(c, &((unsigned char*)regs->bpc)[i])) {
 217 bad:
 218                                 printk(" Bad PC value.");
 219                                 break;
 220                         }
 221                         printk("%02x ", c);
 222                 }
 223         }
 224         printk("\n");
 225 }
 226
 227 static DEFINE_SPINLOCK(die_lock);
 228
 229 void die(const char * str, struct pt_regs * regs, long err)
 230 {
 231         console_verbose();
 232         spin_lock_irq(&die_lock);
 233         bust_spinlocks(1);
 234         printk("%s: %04lx\n", str, err & 0xffff);
 235         show_registers(regs);
 236         bust_spinlocks(0);
 237         spin_unlock_irq(&die_lock);
 238         do_exit(SIGSEGV);
 239 }
 240
 241 static __inline__ void die_if_kernel(const char * str,
 242         struct pt_regs * regs, long err)
 243 {
 244         if (!user_mode(regs))
 245                 die(str, regs, err);
 246 }
 247
 248 static __inline__ void do_trap(int trapnr, int signr, const char * str,
 249         struct pt_regs * regs, long error_code, siginfo_t *info)
 250 {
 251         if (user_mode(regs)) {
 252                 /* trap_signal */
 253                 struct task_struct *tsk = current;
 254                 tsk->thread.error_code = error_code;
 255                 tsk->thread.trap_no = trapnr;
 256                 if (info)
 257                         force_sig_info(signr, info, tsk);
 258                 else
 259                         force_sig(signr, tsk);
 260                 return;
 261         } else {
 262                 /* kernel_trap */
 263                 if (!fixup_exception(regs))
 264                         die(str, regs, error_code);
 265                 return;
 266         }
 267 }
 268
 269 #define DO_ERROR(trapnr, signr, str, name) \
 270 asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
 271 { \
 272         do_trap(trapnr, signr, NULL, regs, error_code, NULL); \
 273 }
 274
 275 #define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \
 276 asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
 277 { \
 278         siginfo_t info; \
 279         info.si_signo = signr; \
 280         info.si_errno = 0; \
 281         info.si_code = sicode; \
 282         info.si_addr = (void __user *)siaddr; \
 283         do_trap(trapnr, signr, str, regs, error_code, &info); \
 284 }
 285
 286 DO_ERROR( 1, SIGTRAP, "debug trap", debug_trap)
 287 DO_ERROR_INFO(0x20, SIGILL,  "reserved instruction ", rie_handler, ILL_ILLOPC, regs->bpc)
 288 DO_ERROR_INFO(0x100, SIGILL,  "privileged instruction", pie_handler, ILL_PRVOPC, regs->bpc)
 289 DO_ERROR_INFO(-1, SIGILL,  "illegal trap", ill_trap, ILL_ILLTRP, regs->bpc)
 290
 291 extern int handle_unaligned_access(unsigned long, struct pt_regs *);
 292
 293 /* This code taken from arch/sh/kernel/traps.c */
 294 asmlinkage void do_alignment_check(struct pt_regs *regs, long error_code)
 295 {
 296         mm_segment_t oldfs;
 297         unsigned long insn;
 298         int tmp;
 299
 300         oldfs = get_fs();
 301
 302         if (user_mode(regs)) {
 303                 local_irq_enable();
 304                 current->thread.error_code = error_code;
 305                 current->thread.trap_no = 0x17;
 306
 307                 set_fs(USER_DS);
 308                 if (copy_from_user(&insn, (void *)regs->bpc, 4)) {
 309                         set_fs(oldfs);
 310                         goto uspace_segv;
 311                 }
 312                 tmp = handle_unaligned_access(insn, regs);
 313                 set_fs(oldfs);
 314
 315                 if (!tmp)
 316                         return;
 317
 318         uspace_segv:
 319                 printk(KERN_NOTICE "Killing process \"%s\" due to unaligned "
 320                         "access\n", current->comm);
 321                 force_sig(SIGSEGV, current);
 322         } else {
 323                 set_fs(KERNEL_DS);
 324                 if (copy_from_user(&insn, (void *)regs->bpc, 4)) {
 325                         set_fs(oldfs);
 326                         die("insn faulting in do_address_error", regs, 0);
 327                 }
 328                 handle_unaligned_access(insn, regs);
 329                 set_fs(oldfs);
 330         }
 331 }