[PATCH v7 23/37] nds32: Debugging support

From: Greentime Hu
Date: Tue Feb 13 2018 - 04:32:10 EST


This patch adds ptrace support.

Signed-off-by: Vincent Chen <vincentc@xxxxxxxxxxxxx>
Signed-off-by: Greentime Hu <greentime@xxxxxxxxxxxxx>
---
arch/nds32/include/uapi/asm/ptrace.h | 25 ++++++++
arch/nds32/kernel/ptrace.c | 119 +++++++++++++++++++++++++++++++++++
2 files changed, 144 insertions(+)
create mode 100644 arch/nds32/include/uapi/asm/ptrace.h
create mode 100644 arch/nds32/kernel/ptrace.c

diff --git a/arch/nds32/include/uapi/asm/ptrace.h b/arch/nds32/include/uapi/asm/ptrace.h
new file mode 100644
index 000000000000..358c99e399d0
--- /dev/null
+++ b/arch/nds32/include/uapi/asm/ptrace.h
@@ -0,0 +1,25 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#ifndef __UAPI_ASM_NDS32_PTRACE_H
+#define __UAPI_ASM_NDS32_PTRACE_H
+
+#ifndef __ASSEMBLY__
+
+/*
+ * User structures for general purpose register.
+ */
+struct user_pt_regs {
+ long uregs[26];
+ long fp;
+ long gp;
+ long lp;
+ long sp;
+ long ipc;
+ long lb;
+ long le;
+ long lc;
+ long syscallno;
+};
+#endif
+#endif
diff --git a/arch/nds32/kernel/ptrace.c b/arch/nds32/kernel/ptrace.c
new file mode 100644
index 000000000000..eaaf7a999b20
--- /dev/null
+++ b/arch/nds32/kernel/ptrace.c
@@ -0,0 +1,119 @@
+// SPDX-License-Identifier: GPL-2.0
+// Copyright (C) 2005-2017 Andes Technology Corporation
+
+#include <linux/ptrace.h>
+#include <linux/regset.h>
+#include <linux/tracehook.h>
+#include <linux/elf.h>
+#include <linux/sched/task_stack.h>
+
+enum nds32_regset {
+ REGSET_GPR,
+};
+
+static int gpr_get(struct task_struct *target,
+ const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ void *kbuf, void __user * ubuf)
+{
+ struct user_pt_regs *uregs = &task_pt_regs(target)->user_regs;
+ return user_regset_copyout(&pos, &count, &kbuf, &ubuf, uregs, 0, -1);
+}
+
+static int gpr_set(struct task_struct *target, const struct user_regset *regset,
+ unsigned int pos, unsigned int count,
+ const void *kbuf, const void __user * ubuf)
+{
+ int err;
+ struct user_pt_regs newregs = task_pt_regs(target)->user_regs;
+
+ err = user_regset_copyin(&pos, &count, &kbuf, &ubuf, &newregs, 0, -1);
+ if (err)
+ return err;
+
+ task_pt_regs(target)->user_regs = newregs;
+ return 0;
+}
+
+static const struct user_regset nds32_regsets[] = {
+ [REGSET_GPR] = {
+ .core_note_type = NT_PRSTATUS,
+ .n = sizeof(struct user_pt_regs) / sizeof(u32),
+ .size = sizeof(elf_greg_t),
+ .align = sizeof(elf_greg_t),
+ .get = gpr_get,
+ .set = gpr_set}
+};
+
+static const struct user_regset_view nds32_user_view = {
+ .name = "nds32",
+ .e_machine = EM_NDS32,
+ .regsets = nds32_regsets,
+ .n = ARRAY_SIZE(nds32_regsets)
+};
+
+const struct user_regset_view *task_user_regset_view(struct task_struct *task)
+{
+ return &nds32_user_view;
+}
+
+void ptrace_disable(struct task_struct *child)
+{
+ user_disable_single_step(child);
+}
+
+/* do_ptrace()
+ *
+ * Provide ptrace defined service.
+ */
+long arch_ptrace(struct task_struct *child, long request, unsigned long addr,
+ unsigned long data)
+{
+ int ret = -EIO;
+
+ switch (request) {
+ default:
+ ret = ptrace_request(child, request, addr, data);
+ break;
+ }
+
+ return ret;
+}
+
+void user_enable_single_step(struct task_struct *child)
+{
+ struct pt_regs *regs;
+ regs = task_pt_regs(child);
+ regs->ipsw |= PSW_mskHSS;
+ set_tsk_thread_flag(child, TIF_SINGLESTEP);
+}
+
+void user_disable_single_step(struct task_struct *child)
+{
+ struct pt_regs *regs;
+ regs = task_pt_regs(child);
+ regs->ipsw &= ~PSW_mskHSS;
+ clear_tsk_thread_flag(child, TIF_SINGLESTEP);
+}
+
+/* sys_trace()
+ *
+ * syscall trace handler.
+ */
+
+asmlinkage int syscall_trace_enter(struct pt_regs *regs)
+{
+ if (test_thread_flag(TIF_SYSCALL_TRACE)) {
+ if (tracehook_report_syscall_entry(regs))
+ forget_syscall(regs);
+ }
+ return regs->syscallno;
+}
+
+asmlinkage void syscall_trace_leave(struct pt_regs *regs)
+{
+ int step = test_thread_flag(TIF_SINGLESTEP);
+ if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall_exit(regs, step);
+
+}
--
2.16.1