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                       struct membuf to)
  25{
  26        const struct pt_regs *regs = task_pt_regs(target);
  27        const struct switch_stack *sw = (struct switch_stack *)regs - 1;
  28
  29        membuf_zero(&to, 4); // R0
  30        membuf_write(&to, &regs->r1, 7 * 4); // R1..R7
  31        membuf_write(&to, &regs->r8, 8 * 4); // R8..R15
  32        membuf_write(&to, sw, 8 * 4); // R16..R23
  33        membuf_zero(&to, 2 * 4); /* et and bt */
  34        membuf_store(&to, regs->gp);
  35        membuf_store(&to, regs->sp);
  36        membuf_store(&to, regs->fp);
  37        membuf_store(&to, regs->ea);
  38        membuf_zero(&to, 4); // PTR_BA
  39        membuf_store(&to, regs->ra);
  40        membuf_store(&to, regs->ea); /* use ea for PC */
  41        return membuf_zero(&to, (NUM_PTRACE_REG - PTR_PC) * 4);
  42}
  43
  44/*
  45 * Set the thread state from a regset passed in via ptrace
  46 */
  47static int genregs_set(struct task_struct *target,
  48                       const struct user_regset *regset,
  49                       unsigned int pos, unsigned int count,
  50                       const void *kbuf, const void __user *ubuf)
  51{
  52        struct pt_regs *regs = task_pt_regs(target);
  53        const struct switch_stack *sw = (struct switch_stack *)regs - 1;
  54        int ret = 0;
  55
  56#define REG_IGNORE_RANGE(START, END)            \
  57        if (!ret)                                       \
  58                ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, \
  59                        START * 4, (END * 4) + 4);
  60
  61#define REG_IN_ONE(PTR, LOC)    \
  62        if (!ret)                       \
  63                ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
  64                        (void *)(PTR), LOC * 4, (LOC * 4) + 4);
  65
  66#define REG_IN_RANGE(PTR, START, END)   \
  67        if (!ret)                               \
  68                ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, \
  69                        (void *)(PTR), START * 4, (END * 4) + 4);
  70
  71        REG_IGNORE_RANGE(PTR_R0, PTR_R0);
  72        REG_IN_RANGE(&regs->r1, PTR_R1, PTR_R7);
  73        REG_IN_RANGE(&regs->r8, PTR_R8, PTR_R15);
  74        REG_IN_RANGE(sw, PTR_R16, PTR_R23);
  75        REG_IGNORE_RANGE(PTR_R24, PTR_R25); /* et and bt */
  76        REG_IN_ONE(&regs->gp, PTR_GP);
  77        REG_IN_ONE(&regs->sp, PTR_SP);
  78        REG_IN_ONE(&regs->fp, PTR_FP);
  79        REG_IN_ONE(&regs->ea, PTR_EA);
  80        REG_IGNORE_RANGE(PTR_BA, PTR_BA);
  81        REG_IN_ONE(&regs->ra, PTR_RA);
  82        REG_IN_ONE(&regs->ea, PTR_PC); /* use ea for PC */
  83        if (!ret)
  84                ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf,
  85                                         PTR_STATUS * 4, -1);
  86
  87        return ret;
  88}
  89
  90/*
  91 * Define the register sets available on Nios2 under Linux
  92 */
  93enum nios2_regset {
  94        REGSET_GENERAL,
  95};
  96
  97static const struct user_regset nios2_regsets[] = {
  98        [REGSET_GENERAL] = {
  99                .core_note_type = NT_PRSTATUS,
 100                .n = NUM_PTRACE_REG,
 101                .size = sizeof(unsigned long),
 102                .align = sizeof(unsigned long),
 103                .regset_get = genregs_get,
 104                .set = genregs_set,
 105        }
 106};
 107
 108static const struct user_regset_view nios2_user_view = {
 109        .name = "nios2",
 110        .e_machine = ELF_ARCH,
 111        .ei_osabi = ELF_OSABI,
 112        .regsets = nios2_regsets,
 113        .n = ARRAY_SIZE(nios2_regsets)
 114};
 115
 116const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 117{
 118        return &nios2_user_view;
 119}
 120
 121void ptrace_disable(struct task_struct *child)
 122{
 123
 124}
 125
 126long arch_ptrace(struct task_struct *child, long request, unsigned long addr,
 127                 unsigned long data)
 128{
 129        return ptrace_request(child, request, addr, data);
 130}
 131
 132asmlinkage int do_syscall_trace_enter(void)
 133{
 134        int ret = 0;
 135
 136        if (test_thread_flag(TIF_SYSCALL_TRACE))
 137                ret = tracehook_report_syscall_entry(task_pt_regs(current));
 138
 139        return ret;
 140}
 141
 142asmlinkage void do_syscall_trace_exit(void)
 143{
 144        if (test_thread_flag(TIF_SYSCALL_TRACE))
 145                tracehook_report_syscall_exit(task_pt_regs(current), 0);
 146}
 147