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