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