LXR linux/arch/nios2/kernel/ptrace.c

   1/*
   2 * Copyright (C) 2014 Altera Corporation
   3 * Copyright (C) 2010 Tobias Klauser <tklauser@distanz.ch>
   4 *
   5 * This file is subject to the terms and conditions of the GNU General
   6 * Public License.  See the file COPYING in the main directory of this
   7 * archive for more details.
   8 */
   9
  10#include <linux/elf.h>
  11#include <linux/errno.h>
  12#include <linux/kernel.h>
  13#include <linux/mm.h>
  14#include <linux/ptrace.h>
  15#include <linux/regset.h>
  16#include <linux/sched.h>
  17#include <linux/sched/task_stack.h>
  18#include <linux/tracehook.h>
  19#include <linux/uaccess.h>
  20#include <linux/user.h>
  21
  22static int genregs_get(struct task_struct *target,
  23                       const struct user_regset *regset,
  24                       unsigned int pos, unsigned int count,
  25                       void *kbuf, void __user *ubuf)
  26{
  27        const struct pt_regs *regs = task_pt_regs(target);
  28        const struct switch_stack *sw = (struct switch_stack *)regs - 1;
  29        int ret = 0;
  30
  31#define REG_O_ZERO_RANGE(START, END)            \
  32        if (!ret)                                       \
  33                ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, \
  34                        START * 4, (END * 4) + 4);
  35
  36#define REG_O_ONE(PTR, LOC)     \
  37        if (!ret)                       \
  38                ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \
  39                        LOC * 4, (LOC * 4) + 4);
  40
  41#define REG_O_RANGE(PTR, START, END)    \
  42        if (!ret)                               \
  43                ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, PTR, \
  44                        START * 4, (END * 4) + 4);
  45
  46        REG_O_ZERO_RANGE(PTR_R0, PTR_R0);
  47        REG_O_RANGE(&regs->r1, PTR_R1, PTR_R7);
  48        REG_O_RANGE(&regs->r8, PTR_R8, PTR_R15);
  49        REG_O_RANGE(sw, PTR_R16, PTR_R23);
  50        REG_O_ZERO_RANGE(PTR_R24, PTR_R25); /* et and bt */
  51        REG_O_ONE(&regs->gp, PTR_GP);
  52        REG_O_ONE(&regs->sp, PTR_SP);
  53        REG_O_ONE(&regs->fp, PTR_FP);
  54        REG_O_ONE(&regs->ea, PTR_EA);
  55        REG_O_ZERO_RANGE(PTR_BA, PTR_BA);
  56        REG_O_ONE(&regs->ra, PTR_RA);
  57        REG_O_ONE(&regs->ea, PTR_PC); /* use ea for PC */
  58        if (!ret)
  59                ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf,
  60                                         PTR_STATUS * 4, -1);
  61
  62        return ret;
  63}
  64
  65/*
  66 * Set the thread state from a regset passed in via ptrace
  67 */
  68static int genregs_set(struct task_struct *target,
  69                       const struct user_regset *regset,
  70                       unsigned int pos, unsigned int count,
  71                       const void *kbuf, const void __user *ubuf)
  72{
  73        struct pt_regs *regs = task_pt_regs(target);
  74        const struct switch_stack *sw = (struct switch_stack *)regs - 1;
  75        int ret = 0;
  76
  77#define REG_IGNORE_RANGE(START, END)            \
  78        if (!ret)                                       \
  79                ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \
  80                        START * 4, (END * 4) + 4);
  81
  82#define REG_IN_ONE(PTR, LOC)    \
  83        if (!ret)                       \
  84                ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
  85                        (void *)(PTR), LOC * 4, (LOC * 4) + 4);
  86
  87#define REG_IN_RANGE(PTR, START, END)   \
  88        if (!ret)                               \
  89                ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
  90                        (void *)(PTR), START * 4, (END * 4) + 4);
  91
  92        REG_IGNORE_RANGE(PTR_R0, PTR_R0);
  93        REG_IN_RANGE(&regs->r1, PTR_R1, PTR_R7);
  94        REG_IN_RANGE(&regs->r8, PTR_R8, PTR_R15);
  95        REG_IN_RANGE(sw, PTR_R16, PTR_R23);
  96        REG_IGNORE_RANGE(PTR_R24, PTR_R25); /* et and bt */
  97        REG_IN_ONE(&regs->gp, PTR_GP);
  98        REG_IN_ONE(&regs->sp, PTR_SP);
  99        REG_IN_ONE(&regs->fp, PTR_FP);
 100        REG_IN_ONE(&regs->ea, PTR_EA);
 101        REG_IGNORE_RANGE(PTR_BA, PTR_BA);
 102        REG_IN_ONE(&regs->ra, PTR_RA);
 103        REG_IN_ONE(&regs->ea, PTR_PC); /* use ea for PC */
 104        if (!ret)
 105                ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
 106                                         PTR_STATUS * 4, -1);
 107
 108        return ret;
 109}
 110
 111/*
 112 * Define the register sets available on Nios2 under Linux
 113 */
 114enum nios2_regset {
 115        REGSET_GENERAL,
 116};
 117
 118static const struct user_regset nios2_regsets[] = {
 119        [REGSET_GENERAL] = {
 120                .core_note_type = NT_PRSTATUS,
 121                .n = NUM_PTRACE_REG,
 122                .size = sizeof(unsigned long),
 123                .align = sizeof(unsigned long),
 124                .get = genregs_get,
 125                .set = genregs_set,
 126        }
 127};
 128
 129static const struct user_regset_view nios2_user_view = {
 130        .name = "nios2",
 131        .e_machine = ELF_ARCH,
 132        .ei_osabi = ELF_OSABI,
 133        .regsets = nios2_regsets,
 134        .n = ARRAY_SIZE(nios2_regsets)
 135};
 136
 137const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 138{
 139        return &nios2_user_view;
 140}
 141
 142void ptrace_disable(struct task_struct *child)
 143{
 144
 145}
 146
 147long arch_ptrace(struct task_struct *child, long request, unsigned long addr,
 148                 unsigned long data)
 149{
 150        return ptrace_request(child, request, addr, data);
 151}
 152
 153asmlinkage int do_syscall_trace_enter(void)
 154{
 155        int ret = 0;
 156
 157        if (test_thread_flag(TIF_SYSCALL_TRACE))
 158                ret = tracehook_report_syscall_entry(task_pt_regs(current));
 159
 160        return ret;
 161}
 162
 163asmlinkage void do_syscall_trace_exit(void)
 164{
 165        if (test_thread_flag(TIF_SYSCALL_TRACE))
 166                tracehook_report_syscall_exit(task_pt_regs(current), 0);
 167}
 168