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