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
  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 *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  */
  67 static 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  */
 113 enum nios2_regset {
 114         REGSET_GENERAL,
 115 };
 116
 117 static 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
 128 static 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
 136 const struct user_regset_view *task_user_regset_view(struct task_struct *task)
 137 {
 138         return &nios2_user_view;
 139 }
 140
 141 void ptrace_disable(struct task_struct *child)
 142 {
 143
 144 }
 145
 146 long 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
 152 asmlinkage 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
 162 asmlinkage 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 }