diff options
Diffstat (limited to 'arch/openrisc/kernel/ptrace.c')
| -rw-r--r-- | arch/openrisc/kernel/ptrace.c | 206 |
1 files changed, 206 insertions, 0 deletions
diff --git a/arch/openrisc/kernel/ptrace.c b/arch/openrisc/kernel/ptrace.c new file mode 100644 index 00000000000..71a2a0c34c6 --- /dev/null +++ b/arch/openrisc/kernel/ptrace.c @@ -0,0 +1,206 @@ +/* + * OpenRISC ptrace.c + * + * Linux architectural port borrowing liberally from similar works of + * others. All original copyrights apply as per the original source + * declaration. + * + * Modifications for the OpenRISC architecture: + * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com> + * Copyright (C) 2005 Gyorgy Jeney <nog@bsemi.com> + * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se> + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#include <stddef.h> +#include <linux/kernel.h> +#include <linux/sched.h> +#include <linux/string.h> + +#include <linux/mm.h> +#include <linux/errno.h> +#include <linux/ptrace.h> +#include <linux/audit.h> +#include <linux/regset.h> +#include <linux/tracehook.h> +#include <linux/elf.h> + +#include <asm/thread_info.h> +#include <asm/segment.h> +#include <asm/page.h> +#include <asm/pgtable.h> + +/* + * Copy the thread state to a regset that can be interpreted by userspace. + * + * It doesn't matter what our internal pt_regs structure looks like. The + * important thing is that we export a consistent view of the thread state + * to userspace. As such, we need to make sure that the regset remains + * ABI compatible as defined by the struct user_regs_struct: + * + * (Each item is a 32-bit word) + * r0 = 0 (exported for clarity) + * 31 GPRS r1-r31 + * PC (Program counter) + * SR (Supervision register) + */ +static int genregs_get(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + void *kbuf, void __user * ubuf) +{ + const struct pt_regs *regs = task_pt_regs(target); + int ret; + + /* r0 */ + ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, 0, 4); + + if (!ret) + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, + regs->gpr+1, 4, 4*32); + if (!ret) + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, + ®s->pc, 4*32, 4*33); + if (!ret) + ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf, + ®s->sr, 4*33, 4*34); + if (!ret) + ret = user_regset_copyout_zero(&pos, &count, &kbuf, &ubuf, + 4*34, -1); + + return ret; +} + +/* + * Set the thread state from a regset passed in via ptrace + */ +static int genregs_set(struct task_struct *target, + const struct user_regset *regset, + unsigned int pos, unsigned int count, + const void *kbuf, const void __user * ubuf) +{ + struct pt_regs *regs = task_pt_regs(target); + int ret; + + /* ignore r0 */ + ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, 0, 4); + /* r1 - r31 */ + if (!ret) + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + regs->gpr+1, 4, 4*32); + /* PC */ + if (!ret) + ret = user_regset_copyin(&pos, &count, &kbuf, &ubuf, + ®s->pc, 4*32, 4*33); + /* + * Skip SR and padding... userspace isn't allowed to changes bits in + * the Supervision register + */ + if (!ret) + ret = user_regset_copyin_ignore(&pos, &count, &kbuf, &ubuf, + 4*33, -1); + + return ret; +} + +/* + * Define the register sets available on OpenRISC under Linux + */ +enum or1k_regset { + REGSET_GENERAL, +}; + +static const struct user_regset or1k_regsets[] = { + [REGSET_GENERAL] = { + .core_note_type = NT_PRSTATUS, + .n = ELF_NGREG, + .size = sizeof(long), + .align = sizeof(long), + .get = genregs_get, + .set = genregs_set, + }, +}; + +static const struct user_regset_view user_or1k_native_view = { + .name = "or1k", + .e_machine = EM_OPENRISC, + .regsets = or1k_regsets, + .n = ARRAY_SIZE(or1k_regsets), +}; + +const struct user_regset_view *task_user_regset_view(struct task_struct *task) +{ + return &user_or1k_native_view; +} + +/* + * does not yet catch signals sent when the child dies. + * in exit.c or in signal.c. + */ + + +/* + * Called by kernel/ptrace.c when detaching.. + * + * Make sure the single step bit is not set. + */ +void ptrace_disable(struct task_struct *child) +{ + pr_debug("ptrace_disable(): TODO\n"); + + user_disable_single_step(child); + clear_tsk_thread_flag(child, TIF_SYSCALL_TRACE); +} + +long arch_ptrace(struct task_struct *child, long request, unsigned long addr, + unsigned long data) +{ + int ret; + + switch (request) { + default: + ret = ptrace_request(child, request, addr, data); + break; + } + + return ret; +} + +/* + * Notification of system call entry/exit + * - triggered by current->work.syscall_trace + */ +asmlinkage long do_syscall_trace_enter(struct pt_regs *regs) +{ + long ret = 0; + + if (test_thread_flag(TIF_SYSCALL_TRACE) && + tracehook_report_syscall_entry(regs)) + /* + * Tracing decided this syscall should not happen. + * We'll return a bogus call number to get an ENOSYS + * error, but leave the original number in <something>. + */ + ret = -1L; + + audit_syscall_entry(AUDIT_ARCH_OPENRISC, regs->gpr[11], + regs->gpr[3], regs->gpr[4], + regs->gpr[5], regs->gpr[6]); + + return ret ? : regs->gpr[11]; +} + +asmlinkage void do_syscall_trace_leave(struct pt_regs *regs) +{ + int step; + + audit_syscall_exit(regs); + + step = test_thread_flag(TIF_SINGLESTEP); + if (step || test_thread_flag(TIF_SYSCALL_TRACE)) + tracehook_report_syscall_exit(regs, step); +} |