Jonas Bonn | e5ad95c | 2011-06-04 21:54:22 +0300 | [diff] [blame] | 1 | /* |
| 2 | * OpenRISC ptrace.c |
| 3 | * |
| 4 | * Linux architectural port borrowing liberally from similar works of |
| 5 | * others. All original copyrights apply as per the original source |
| 6 | * declaration. |
| 7 | * |
| 8 | * Modifications for the OpenRISC architecture: |
| 9 | * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com> |
| 10 | * Copyright (C) 2005 Gyorgy Jeney <nog@bsemi.com> |
| 11 | * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se> |
| 12 | * |
| 13 | * This program is free software; you can redistribute it and/or |
| 14 | * modify it under the terms of the GNU General Public License |
| 15 | * as published by the Free Software Foundation; either version |
| 16 | * 2 of the License, or (at your option) any later version. |
| 17 | */ |
| 18 | |
| 19 | #include <stddef.h> |
| 20 | #include <linux/kernel.h> |
| 21 | #include <linux/sched.h> |
| 22 | #include <linux/string.h> |
| 23 | |
| 24 | #include <linux/mm.h> |
| 25 | #include <linux/errno.h> |
| 26 | #include <linux/ptrace.h> |
| 27 | #include <linux/audit.h> |
| 28 | #include <linux/regset.h> |
| 29 | #include <linux/tracehook.h> |
| 30 | #include <linux/elf.h> |
| 31 | |
| 32 | #include <asm/thread_info.h> |
| 33 | #include <asm/segment.h> |
| 34 | #include <asm/page.h> |
| 35 | #include <asm/pgtable.h> |
| 36 | #include <asm/system.h> |
| 37 | |
| 38 | /* |
| 39 | * Copy the thread state to a regset that can be interpreted by userspace. |
| 40 | * |
| 41 | * It doesn't matter what our internal pt_regs structure looks like. The |
| 42 | * important thing is that we export a consistent view of the thread state |
| 43 | * to userspace. As such, we need to make sure that the regset remains |
| 44 | * ABI compatible as defined by the struct user_regs_struct: |
| 45 | * |
| 46 | * (Each item is a 32-bit word) |
| 47 | * r0 = 0 (exported for clarity) |
| 48 | * 31 GPRS r1-r31 |
| 49 | * PC (Program counter) |
| 50 | * SR (Supervision register) |
| 51 | */ |
| 52 | static int genregs_get(struct task_struct *target, |
| 53 | const struct user_regset *regset, |
| 54 | unsigned int pos, unsigned int count, |
| 55 | void *kbuf, void __user * ubuf) |
| 56 | { |
| 57 | const struct pt_regs *regs = task_pt_regs(target); |
| 58 | int ret; |
| 59 | |
| 60 | /* r0 */ |
| 61 | ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, 0, 4); |
| 62 | |
| 63 | if (!ret) |
| 64 | ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, |
| 65 | regs->gpr+1, 4, 4*32); |
| 66 | if (!ret) |
| 67 | ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, |
| 68 | ®s->pc, 4*32, 4*33); |
| 69 | if (!ret) |
| 70 | ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, |
| 71 | ®s->sr, 4*33, 4*34); |
| 72 | if (!ret) |
| 73 | ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, |
| 74 | 4*34, -1); |
| 75 | |
| 76 | return ret; |
| 77 | } |
| 78 | |
| 79 | /* |
| 80 | * Set the thread state from a regset passed in via ptrace |
| 81 | */ |
| 82 | static int genregs_set(struct task_struct *target, |
| 83 | const struct user_regset *regset, |
| 84 | unsigned int pos, unsigned int count, |
| 85 | const void *kbuf, const void __user * ubuf) |
| 86 | { |
| 87 | struct pt_regs *regs = task_pt_regs(target); |
| 88 | int ret; |
| 89 | |
| 90 | /* ignore r0 */ |
| 91 | ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, 4); |
| 92 | /* r1 - r31 */ |
| 93 | if (!ret) |
| 94 | ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, |
| 95 | regs->gpr+1, 4, 4*32); |
| 96 | /* PC */ |
| 97 | if (!ret) |
| 98 | ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, |
| 99 | ®s->pc, 4*32, 4*33); |
| 100 | /* |
| 101 | * Skip SR and padding... userspace isn't allowed to changes bits in |
| 102 | * the Supervision register |
| 103 | */ |
| 104 | if (!ret) |
| 105 | ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, |
| 106 | 4*33, -1); |
| 107 | |
| 108 | return ret; |
| 109 | } |
| 110 | |
| 111 | /* |
| 112 | * Define the register sets available on OpenRISC under Linux |
| 113 | */ |
| 114 | enum or1k_regset { |
| 115 | REGSET_GENERAL, |
| 116 | }; |
| 117 | |
| 118 | static const struct user_regset or1k_regsets[] = { |
| 119 | [REGSET_GENERAL] = { |
| 120 | .core_note_type = NT_PRSTATUS, |
| 121 | .n = ELF_NGREG, |
| 122 | .size = sizeof(long), |
| 123 | .align = sizeof(long), |
| 124 | .get = genregs_get, |
| 125 | .set = genregs_set, |
| 126 | }, |
| 127 | }; |
| 128 | |
| 129 | static const struct user_regset_view user_or1k_native_view = { |
| 130 | .name = "or1k", |
| 131 | .e_machine = EM_OPENRISC, |
| 132 | .regsets = or1k_regsets, |
| 133 | .n = ARRAY_SIZE(or1k_regsets), |
| 134 | }; |
| 135 | |
| 136 | const struct user_regset_view *task_user_regset_view(struct task_struct *task) |
| 137 | { |
| 138 | return &user_or1k_native_view; |
| 139 | } |
| 140 | |
| 141 | /* |
| 142 | * does not yet catch signals sent when the child dies. |
| 143 | * in exit.c or in signal.c. |
| 144 | */ |
| 145 | |
| 146 | |
| 147 | /* |
| 148 | * Called by kernel/ptrace.c when detaching.. |
| 149 | * |
| 150 | * Make sure the single step bit is not set. |
| 151 | */ |
| 152 | void ptrace_disable(struct task_struct *child) |
| 153 | { |
| 154 | pr_debug("ptrace_disable(): TODO\n"); |
| 155 | |
| 156 | user_disable_single_step(child); |
| 157 | clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); |
| 158 | } |
| 159 | |
| 160 | long arch_ptrace(struct task_struct *child, long request, unsigned long addr, |
| 161 | unsigned long data) |
| 162 | { |
| 163 | int ret; |
| 164 | |
| 165 | switch (request) { |
| 166 | default: |
| 167 | ret = ptrace_request(child, request, addr, data); |
| 168 | break; |
| 169 | } |
| 170 | |
| 171 | return ret; |
| 172 | } |
| 173 | |
| 174 | /* |
| 175 | * Notification of system call entry/exit |
| 176 | * - triggered by current->work.syscall_trace |
| 177 | */ |
| 178 | asmlinkage long do_syscall_trace_enter(struct pt_regs *regs) |
| 179 | { |
| 180 | long ret = 0; |
| 181 | |
| 182 | if (test_thread_flag(TIF_SYSCALL_TRACE) && |
| 183 | tracehook_report_syscall_entry(regs)) |
| 184 | /* |
| 185 | * Tracing decided this syscall should not happen. |
| 186 | * We'll return a bogus call number to get an ENOSYS |
| 187 | * error, but leave the original number in <something>. |
| 188 | */ |
| 189 | ret = -1L; |
| 190 | |
Jonas Bonn | 3f6ffc8 | 2012-02-15 15:02:20 +0100 | [diff] [blame] | 191 | audit_syscall_entry(audit_arch(), regs->syscallno, |
| 192 | regs->gpr[3], regs->gpr[4], |
| 193 | regs->gpr[5], regs->gpr[6]); |
Jonas Bonn | e5ad95c | 2011-06-04 21:54:22 +0300 | [diff] [blame] | 194 | |
| 195 | return ret ? : regs->syscallno; |
| 196 | } |
| 197 | |
| 198 | asmlinkage void do_syscall_trace_leave(struct pt_regs *regs) |
| 199 | { |
| 200 | int step; |
| 201 | |
Jonas Bonn | 3f6ffc8 | 2012-02-15 15:02:20 +0100 | [diff] [blame] | 202 | audit_syscall_exit(regs); |
Jonas Bonn | e5ad95c | 2011-06-04 21:54:22 +0300 | [diff] [blame] | 203 | |
| 204 | step = test_thread_flag(TIF_SINGLESTEP); |
| 205 | if (step || test_thread_flag(TIF_SYSCALL_TRACE)) |
| 206 | tracehook_report_syscall_exit(regs, step); |
| 207 | } |