arch/arc/kernel/ptrace.c

   1 /*
   2  * Copyright (C) 2004, 2007-2010, 2011-2012 Synopsys, Inc. (www.synopsys.com)
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License version 2 as
   6  * published by the Free Software Foundation.
   7  */
   8
   9 #include <linux/ptrace.h>
  10 #include <linux/tracehook.h>
  11 #include <linux/regset.h>
  12 #include <linux/unistd.h>
  13 #include <linux/elf.h>
  14
  15 static struct callee_regs *task_callee_regs(struct task_struct *tsk)
  16 {
  17         struct callee_regs *tmp = (struct callee_regs *)tsk->thread.callee_reg;
  18         return tmp;
  19 }
  20
  21 static int genregs_get(struct task_struct *target,
  22                        const struct user_regset *regset,
  23                        unsigned int pos, unsigned int count,
  24                        void *kbuf, void __user *ubuf)
  25 {
  26         const struct pt_regs *ptregs = task_pt_regs(target);
  27         const struct callee_regs *cregs = task_callee_regs(target);
  28         int ret = 0;
  29         unsigned int stop_pc_val;
  30
  31 #define REG_O_CHUNK(START, END, PTR)    \
  32         if (!ret)       \
  33                 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \
  34                         offsetof(struct user_regs_struct, START), \
  35                         offsetof(struct user_regs_struct, END));
  36
  37 #define REG_O_ONE(LOC, PTR)     \
  38         if (!ret)               \
  39                 ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \
  40                         offsetof(struct user_regs_struct, LOC), \
  41                         offsetof(struct user_regs_struct, LOC) + 4);
  42
  43 #define REG_O_ZERO(LOC)         \
  44         if (!ret)               \
  45                 ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, \
  46                         offsetof(struct user_regs_struct, LOC), \
  47                         offsetof(struct user_regs_struct, LOC) + 4);
  48
  49         REG_O_ZERO(pad);
  50         REG_O_ONE(scratch.bta, &ptregs->bta);
  51         REG_O_ONE(scratch.lp_start, &ptregs->lp_start);
  52         REG_O_ONE(scratch.lp_end, &ptregs->lp_end);
  53         REG_O_ONE(scratch.lp_count, &ptregs->lp_count);
  54         REG_O_ONE(scratch.status32, &ptregs->status32);
  55         REG_O_ONE(scratch.ret, &ptregs->ret);
  56         REG_O_ONE(scratch.blink, &ptregs->blink);
  57         REG_O_ONE(scratch.fp, &ptregs->fp);
  58         REG_O_ONE(scratch.gp, &ptregs->r26);
  59         REG_O_ONE(scratch.r12, &ptregs->r12);
  60         REG_O_ONE(scratch.r11, &ptregs->r11);
  61         REG_O_ONE(scratch.r10, &ptregs->r10);
  62         REG_O_ONE(scratch.r9, &ptregs->r9);
  63         REG_O_ONE(scratch.r8, &ptregs->r8);
  64         REG_O_ONE(scratch.r7, &ptregs->r7);
  65         REG_O_ONE(scratch.r6, &ptregs->r6);
  66         REG_O_ONE(scratch.r5, &ptregs->r5);
  67         REG_O_ONE(scratch.r4, &ptregs->r4);
  68         REG_O_ONE(scratch.r3, &ptregs->r3);
  69         REG_O_ONE(scratch.r2, &ptregs->r2);
  70         REG_O_ONE(scratch.r1, &ptregs->r1);
  71         REG_O_ONE(scratch.r0, &ptregs->r0);
  72         REG_O_ONE(scratch.sp, &ptregs->sp);
  73
  74         REG_O_ZERO(pad2);
  75
  76         REG_O_ONE(callee.r25, &cregs->r25);
  77         REG_O_ONE(callee.r24, &cregs->r24);
  78         REG_O_ONE(callee.r23, &cregs->r23);
  79         REG_O_ONE(callee.r22, &cregs->r22);
  80         REG_O_ONE(callee.r21, &cregs->r21);
  81         REG_O_ONE(callee.r20, &cregs->r20);
  82         REG_O_ONE(callee.r19, &cregs->r19);
  83         REG_O_ONE(callee.r18, &cregs->r18);
  84         REG_O_ONE(callee.r17, &cregs->r17);
  85         REG_O_ONE(callee.r16, &cregs->r16);
  86         REG_O_ONE(callee.r15, &cregs->r15);
  87         REG_O_ONE(callee.r14, &cregs->r14);
  88         REG_O_ONE(callee.r13, &cregs->r13);
  89
  90         REG_O_ONE(efa, &target->thread.fault_address);
  91
  92         if (!ret) {
  93                 if (in_brkpt_trap(ptregs)) {
  94                         stop_pc_val = target->thread.fault_address;
  95                         pr_debug("\t\tstop_pc (brk-pt)\n");
  96                 } else {
  97                         stop_pc_val = ptregs->ret;
  98                         pr_debug("\t\tstop_pc (others)\n");
  99                 }
 100
 101                 REG_O_ONE(stop_pc, &stop_pc_val);
 102         }
 103
 104         return ret;
 105 }
 106
 107 static int genregs_set(struct task_struct *target,
 108                        const struct user_regset *regset,
 109                        unsigned int pos, unsigned int count,
 110                        const void *kbuf, const void __user *ubuf)
 111 {
 112         const struct pt_regs *ptregs = task_pt_regs(target);
 113         const struct callee_regs *cregs = task_callee_regs(target);
 114         int ret = 0;
 115
 116 #define REG_IN_CHUNK(FIRST, NEXT, PTR)  \
 117         if (!ret)                       \
 118                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
 119                         (void *)(PTR), \
 120                         offsetof(struct user_regs_struct, FIRST), \
 121                         offsetof(struct user_regs_struct, NEXT));
 122
 123 #define REG_IN_ONE(LOC, PTR)            \
 124         if (!ret)                       \
 125                 ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
 126                         (void *)(PTR), \
 127                         offsetof(struct user_regs_struct, LOC), \
 128                         offsetof(struct user_regs_struct, LOC) + 4);
 129
 130 #define REG_IGNORE_ONE(LOC)             \
 131         if (!ret)                       \
 132                 ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \
 133                         offsetof(struct user_regs_struct, LOC), \
 134                         offsetof(struct user_regs_struct, LOC) + 4);
 135
 136         REG_IGNORE_ONE(pad);
 137
 138         REG_IN_ONE(scratch.bta, &ptregs->bta);
 139         REG_IN_ONE(scratch.lp_start, &ptregs->lp_start);
 140         REG_IN_ONE(scratch.lp_end, &ptregs->lp_end);
 141         REG_IN_ONE(scratch.lp_count, &ptregs->lp_count);
 142
 143         REG_IGNORE_ONE(scratch.status32);
 144
 145         REG_IN_ONE(scratch.ret, &ptregs->ret);
 146         REG_IN_ONE(scratch.blink, &ptregs->blink);
 147         REG_IN_ONE(scratch.fp, &ptregs->fp);
 148         REG_IN_ONE(scratch.gp, &ptregs->r26);
 149         REG_IN_ONE(scratch.r12, &ptregs->r12);
 150         REG_IN_ONE(scratch.r11, &ptregs->r11);
 151         REG_IN_ONE(scratch.r10, &ptregs->r10);
 152         REG_IN_ONE(scratch.r9, &ptregs->r9);
 153         REG_IN_ONE(scratch.r8, &ptregs->r8);
 154         REG_IN_ONE(scratch.r7, &ptregs->r7);
 155         REG_IN_ONE(scratch.r6, &ptregs->r6);
 156         REG_IN_ONE(scratch.r5, &ptregs->r5);
 157         REG_IN_ONE(scratch.r4, &ptregs->r4);
 158         REG_IN_ONE(scratch.r3, &ptregs->r3);
 159         REG_IN_ONE(scratch.r2, &ptregs->r2);
 160         REG_IN_ONE(scratch.r1, &ptregs->r1);
 161         REG_IN_ONE(scratch.r0, &ptregs->r0);
 162         REG_IN_ONE(scratch.sp, &ptregs->sp);
 163
 164         REG_IGNORE_ONE(pad2);
 165
 166         REG_IN_ONE(callee.r25, &cregs->r25);
 167         REG_IN_ONE(callee.r24, &cregs->r24);
 168         REG_IN_ONE(callee.r23, &cregs->r23);
 169         REG_IN_ONE(callee.r22, &cregs->r22);
 170         REG_IN_ONE(callee.r21, &cregs->r21);
 171         REG_IN_ONE(callee.r20, &cregs->r20);
 172         REG_IN_ONE(callee.r19, &cregs->r19);
 173         REG_IN_ONE(callee.r18, &cregs->r18);
 174         REG_IN_ONE(callee.r17, &cregs->r17);
 175         REG_IN_ONE(callee.r16, &cregs->r16);
 176         REG_IN_ONE(callee.r15, &cregs->r15);
 177         REG_IN_ONE(callee.r14, &cregs->r14);
 178         REG_IN_ONE(callee.r13, &cregs->r13);
 179
 180         REG_IGNORE_ONE(efa);                    /* efa update invalid */
 181         REG_IGNORE_ONE(stop_pc);                /* PC updated via @ret */
 182
 183         return ret;
 184 }
 185
 186 enum arc_getset {
 187         REGSET_GENERAL,
 188 };
 189
 190 static const struct user_regset arc_regsets[] = {
 191         [REGSET_GENERAL] = {
 192                .core_note_type = NT_PRSTATUS,
 193                .n = ELF_NGREG,
 194                .size = sizeof(unsigned long),
 195                .align = sizeof(unsigned long),
 196                .get = genregs_get,
 197                .set = genregs_set,
 198         }
 199 };
 200
 201 static const struct user_regset_view user_arc_view = {
 202         .name           = UTS_MACHINE,
 203         .e_machine      = EM_ARC_INUSE,
 204         .regsets        = arc_regsets,
 205         .n              = ARRAY_SIZE(arc_regsets)
 206 };
 207
 208 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 209 {
 210         return &user_arc_view;
 211 }
 212
 213 void ptrace_disable(struct task_struct *child)
 214 {
 215 }
 216
 217 long arch_ptrace(struct task_struct *child, long request,
 218                  unsigned long addr, unsigned long data)
 219 {
 220         int ret = -EIO;
 221
 222         pr_debug("REQ=%ld: ADDR =0x%lx, DATA=0x%lx)\n", request, addr, data);
 223
 224         switch (request) {
 225         case PTRACE_GET_THREAD_AREA:
 226                 ret = put_user(task_thread_info(child)->thr_ptr,
 227                                (unsigned long __user *)data);
 228                 break;
 229         default:
 230                 ret = ptrace_request(child, request, addr, data);
 231                 break;
 232         }
 233
 234         return ret;
 235 }
 236
 237 asmlinkage int syscall_trace_entry(struct pt_regs *regs)
 238 {
 239         if (tracehook_report_syscall_entry(regs))
 240                 return ULONG_MAX;
 241
 242         return regs->r8;
 243 }
 244
 245 asmlinkage void syscall_trace_exit(struct pt_regs *regs)
 246 {
 247         tracehook_report_syscall_exit(regs, 0);
 248 }