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author | GuanXuetao <gxt@mprc.pku.edu.cn> | 2011-01-15 10:21:56 (GMT) |
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committer | GuanXuetao <gxt@mprc.pku.edu.cn> | 2011-03-17 01:19:12 (GMT) |
commit | 6dea1ba1c82013c108d235ec32c6d8bd9ff6b48d (patch) | |
tree | b355276d07db73b1618e045571d13348fd554399 /arch/unicore32/kernel | |
parent | d9bc15794d122cb7bdc9a069d22f3d3166dd31d4 (diff) | |
download | linux-6dea1ba1c82013c108d235ec32c6d8bd9ff6b48d.tar.xz |
unicore32 additional architecture files: ptrace handling
This patch adds ptrace support.
Changed from previous version:
1. disable arch_has_single_step and remove single-step instruction handler
2. add 'Ross Biro 1/23/92' contributor information
3. clean unused codes
Signed-off-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Acked-by: Arnd Bergmann <arnd@arndb.de>
Diffstat (limited to 'arch/unicore32/kernel')
-rw-r--r-- | arch/unicore32/kernel/ptrace.c | 149 |
1 files changed, 149 insertions, 0 deletions
diff --git a/arch/unicore32/kernel/ptrace.c b/arch/unicore32/kernel/ptrace.c new file mode 100644 index 0000000..9f07c08 --- /dev/null +++ b/arch/unicore32/kernel/ptrace.c @@ -0,0 +1,149 @@ +/* + * linux/arch/unicore32/kernel/ptrace.c + * + * Code specific to PKUnity SoC and UniCore ISA + * + * Copyright (C) 2001-2010 GUAN Xue-tao + * + * By Ross Biro 1/23/92 + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#include <linux/kernel.h> +#include <linux/ptrace.h> +#include <linux/signal.h> +#include <linux/uaccess.h> + +/* + * this routine will get a word off of the processes privileged stack. + * the offset is how far from the base addr as stored in the THREAD. + * this routine assumes that all the privileged stacks are in our + * data space. + */ +static inline long get_user_reg(struct task_struct *task, int offset) +{ + return task_pt_regs(task)->uregs[offset]; +} + +/* + * this routine will put a word on the processes privileged stack. + * the offset is how far from the base addr as stored in the THREAD. + * this routine assumes that all the privileged stacks are in our + * data space. + */ +static inline int +put_user_reg(struct task_struct *task, int offset, long data) +{ + struct pt_regs newregs, *regs = task_pt_regs(task); + int ret = -EINVAL; + + newregs = *regs; + newregs.uregs[offset] = data; + + if (valid_user_regs(&newregs)) { + regs->uregs[offset] = data; + ret = 0; + } + + return ret; +} + +/* + * Called by kernel/ptrace.c when detaching.. + */ +void ptrace_disable(struct task_struct *child) +{ +} + +/* + * We actually access the pt_regs stored on the kernel stack. + */ +static int ptrace_read_user(struct task_struct *tsk, unsigned long off, + unsigned long __user *ret) +{ + unsigned long tmp; + + tmp = 0; + if (off < sizeof(struct pt_regs)) + tmp = get_user_reg(tsk, off >> 2); + + return put_user(tmp, ret); +} + +/* + * We actually access the pt_regs stored on the kernel stack. + */ +static int ptrace_write_user(struct task_struct *tsk, unsigned long off, + unsigned long val) +{ + if (off >= sizeof(struct pt_regs)) + return 0; + + return put_user_reg(tsk, off >> 2, val); +} + +long arch_ptrace(struct task_struct *child, long request, + unsigned long addr, unsigned long data) +{ + int ret; + unsigned long __user *datap = (unsigned long __user *) data; + + switch (request) { + case PTRACE_PEEKUSR: + ret = ptrace_read_user(child, addr, datap); + break; + + case PTRACE_POKEUSR: + ret = ptrace_write_user(child, addr, data); + break; + + case PTRACE_GET_THREAD_AREA: + ret = put_user(task_pt_regs(child)->UCreg_16, + datap); + break; + + default: + ret = ptrace_request(child, request, addr, data); + break; + } + + return ret; +} + +asmlinkage int syscall_trace(int why, struct pt_regs *regs, int scno) +{ + unsigned long ip; + + if (!test_thread_flag(TIF_SYSCALL_TRACE)) + return scno; + if (!(current->ptrace & PT_PTRACED)) + return scno; + + /* + * Save IP. IP is used to denote syscall entry/exit: + * IP = 0 -> entry, = 1 -> exit + */ + ip = regs->UCreg_ip; + regs->UCreg_ip = why; + + current_thread_info()->syscall = scno; + + /* the 0x80 provides a way for the tracing parent to distinguish + between a syscall stop and SIGTRAP delivery */ + ptrace_notify(SIGTRAP | ((current->ptrace & PT_TRACESYSGOOD) + ? 0x80 : 0)); + /* + * this isn't the same as continuing with a signal, but it will do + * for normal use. strace only continues with a signal if the + * stopping signal is not SIGTRAP. -brl + */ + if (current->exit_code) { + send_sig(current->exit_code, current, 1); + current->exit_code = 0; + } + regs->UCreg_ip = ip; + + return current_thread_info()->syscall; +} |