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 <linux/uaccess.h>
  22 #include <asm/io.h>
  23 #include <linux/atomic.h>
  24
  25 #include <asm/smp.h>
  26
  27 #include <linux/module.h>
  28
  29 asmlinkage void alignment_check(void);
  30 asmlinkage void ei_handler(void);
  31 asmlinkage void rie_handler(void);
  32 asmlinkage void debug_trap(void);
  33 asmlinkage void cache_flushing_handler(void);
  34 asmlinkage void ill_trap(void);
  35
  36 #ifdef CONFIG_SMP
  37 extern void smp_reschedule_interrupt(void);
  38 extern void smp_invalidate_interrupt(void);
  39 extern void smp_call_function_interrupt(void);
  40 extern void smp_ipi_timer_interrupt(void);
  41 extern void smp_flush_cache_all_interrupt(void);
  42 extern void smp_call_function_single_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 static 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;    /* CPU_BOOT_IPI */
 107         eit_vector[190] = (unsigned long)smp_call_function_single_interrupt;
 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 static int kstack_depth_to_print = 24;
 124
 125 static 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>] %pSR\n", addr, (void *)addr);
 137         }
 138         printk("\n");
 139 }
 140
 141 void show_stack(struct task_struct *task, unsigned long *sp)
 142 {
 143         unsigned long  *stack;
 144         int  i;
 145
 146         /*
 147          * debugging aid: "show_stack(NULL);" prints the
 148          * back trace for this cpu.
 149          */
 150
 151         if(sp==NULL) {
 152                 if (task)
 153                         sp = (unsigned long *)task->thread.sp;
 154                 else
 155                         sp=(unsigned long*)&sp;
 156         }
 157
 158         stack = sp;
 159         for(i=0; i < kstack_depth_to_print; i++) {
 160                 if (kstack_end(stack))
 161                         break;
 162                 if (i && ((i % 4) == 0))
 163                         printk("\n       ");
 164                 printk("%08lx ", *stack++);
 165         }
 166         printk("\n");
 167         show_trace(task, sp);
 168 }
 169
 170 static void show_registers(struct pt_regs *regs)
 171 {
 172         int i = 0;
 173         int in_kernel = 1;
 174         unsigned long sp;
 175
 176         printk("CPU:    %d\n", smp_processor_id());
 177         show_regs(regs);
 178
 179         sp = (unsigned long) (1+regs);
 180         if (user_mode(regs)) {
 181                 in_kernel = 0;
 182                 sp = regs->spu;
 183                 printk("SPU: %08lx\n", sp);
 184         } else {
 185                 printk("SPI: %08lx\n", sp);
 186         }
 187         printk("Process %s (pid: %d, process nr: %d, stackpage=%08lx)",
 188                 current->comm, task_pid_nr(current), 0xffff & i, 4096+(unsigned long)current);
 189
 190         /*
 191          * When in-kernel, we also print out the stack and code at the
 192          * time of the fault..
 193          */
 194         if (in_kernel) {
 195                 printk("\nStack: ");
 196                 show_stack(current, (unsigned long*) sp);
 197
 198                 printk("\nCode: ");
 199                 if (regs->bpc < PAGE_OFFSET)
 200                         goto bad;
 201
 202                 for(i=0;i<20;i++) {
 203                         unsigned char c;
 204                         if (__get_user(c, &((unsigned char*)regs->bpc)[i])) {
 205 bad:
 206                                 printk(" Bad PC value.");
 207                                 break;
 208                         }
 209                         printk("%02x ", c);
 210                 }
 211         }
 212         printk("\n");
 213 }
 214
 215 static DEFINE_SPINLOCK(die_lock);
 216
 217 void die(const char * str, struct pt_regs * regs, long err)
 218 {
 219         console_verbose();
 220         spin_lock_irq(&die_lock);
 221         bust_spinlocks(1);
 222         printk("%s: %04lx\n", str, err & 0xffff);
 223         show_registers(regs);
 224         bust_spinlocks(0);
 225         spin_unlock_irq(&die_lock);
 226         do_exit(SIGSEGV);
 227 }
 228
 229 static __inline__ void die_if_kernel(const char * str,
 230         struct pt_regs * regs, long err)
 231 {
 232         if (!user_mode(regs))
 233                 die(str, regs, err);
 234 }
 235
 236 static __inline__ void do_trap(int trapnr, int signr, const char * str,
 237         struct pt_regs * regs, long error_code, siginfo_t *info)
 238 {
 239         if (user_mode(regs)) {
 240                 /* trap_signal */
 241                 struct task_struct *tsk = current;
 242                 tsk->thread.error_code = error_code;
 243                 tsk->thread.trap_no = trapnr;
 244                 if (info)
 245                         force_sig_info(signr, info, tsk);
 246                 else
 247                         force_sig(signr, tsk);
 248                 return;
 249         } else {
 250                 /* kernel_trap */
 251                 if (!fixup_exception(regs))
 252                         die(str, regs, error_code);
 253                 return;
 254         }
 255 }
 256
 257 #define DO_ERROR(trapnr, signr, str, name) \
 258 asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
 259 { \
 260         do_trap(trapnr, signr, NULL, regs, error_code, NULL); \
 261 }
 262
 263 #define DO_ERROR_INFO(trapnr, signr, str, name, sicode, siaddr) \
 264 asmlinkage void do_##name(struct pt_regs * regs, long error_code) \
 265 { \
 266         siginfo_t info; \
 267         info.si_signo = signr; \
 268         info.si_errno = 0; \
 269         info.si_code = sicode; \
 270         info.si_addr = (void __user *)siaddr; \
 271         do_trap(trapnr, signr, str, regs, error_code, &info); \
 272 }
 273
 274 DO_ERROR( 1, SIGTRAP, "debug trap", debug_trap)
 275 DO_ERROR_INFO(0x20, SIGILL,  "reserved instruction ", rie_handler, ILL_ILLOPC, regs->bpc)
 276 DO_ERROR_INFO(0x100, SIGILL,  "privileged instruction", pie_handler, ILL_PRVOPC, regs->bpc)
 277 DO_ERROR_INFO(-1, SIGILL,  "illegal trap", ill_trap, ILL_ILLTRP, regs->bpc)
 278
 279 extern int handle_unaligned_access(unsigned long, struct pt_regs *);
 280
 281 /* This code taken from arch/sh/kernel/traps.c */
 282 asmlinkage void do_alignment_check(struct pt_regs *regs, long error_code)
 283 {
 284         mm_segment_t oldfs;
 285         unsigned long insn;
 286         int tmp;
 287
 288         oldfs = get_fs();
 289
 290         if (user_mode(regs)) {
 291                 local_irq_enable();
 292                 current->thread.error_code = error_code;
 293                 current->thread.trap_no = 0x17;
 294
 295                 set_fs(USER_DS);
 296                 if (copy_from_user(&insn, (void *)regs->bpc, 4)) {
 297                         set_fs(oldfs);
 298                         goto uspace_segv;
 299                 }
 300                 tmp = handle_unaligned_access(insn, regs);
 301                 set_fs(oldfs);
 302
 303                 if (!tmp)
 304                         return;
 305
 306         uspace_segv:
 307                 printk(KERN_NOTICE "Killing process \"%s\" due to unaligned "
 308                         "access\n", current->comm);
 309                 force_sig(SIGSEGV, current);
 310         } else {
 311                 set_fs(KERNEL_DS);
 312                 if (copy_from_user(&insn, (void *)regs->bpc, 4)) {
 313                         set_fs(oldfs);
 314                         die("insn faulting in do_address_error", regs, 0);
 315                 }
 316                 handle_unaligned_access(insn, regs);
 317                 set_fs(oldfs);
 318         }
 319 }