summaryrefslogtreecommitdiffstats
diff options
context:
space:
mode:
Diffstat
-rw-r--r--arch/openrisc/include/asm/ptrace.h131
-rw-r--r--arch/openrisc/kernel/ptrace.c211
2 files changed, 342 insertions, 0 deletions
diff --git a/arch/openrisc/include/asm/ptrace.h b/arch/openrisc/include/asm/ptrace.h
new file mode 100644
index 000000000000..054537c5f9c9
--- /dev/null
+++ b/arch/openrisc/include/asm/ptrace.h
@@ -0,0 +1,131 @@
+/*
+ * OpenRISC Linux
+ *
+ * Linux architectural port borrowing liberally from similar works of
+ * others. All original copyrights apply as per the original source
+ * declaration.
+ *
+ * OpenRISC implementation:
+ * Copyright (C) 2003 Matjaz Breskvar <phoenix@bsemi.com>
+ * Copyright (C) 2010-2011 Jonas Bonn <jonas@southpole.se>
+ * et al.
+ *
+ * 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.
+ */
+
+#ifndef __ASM_OPENRISC_PTRACE_H
+#define __ASM_OPENRISC_PTRACE_H
+
+#include <asm/spr_defs.h>
+
+#ifndef __ASSEMBLY__
+/*
+ * This is the layout of the regset returned by the GETREGSET ptrace call
+ */
+struct user_regs_struct {
+ /* GPR R0-R31... */
+ unsigned long gpr[32];
+ unsigned long pc;
+ unsigned long sr;
+ unsigned long pad1;
+ unsigned long pad2;
+};
+#endif
+
+#ifdef __KERNEL__
+
+/*
+ * Make kernel PTrace/register structures opaque to userspace... userspace can
+ * access thread state via the regset mechanism. This allows us a bit of
+ * flexibility in how we order the registers on the stack, permitting some
+ * optimizations like packing call-clobbered registers together so that
+ * they share a cacheline (not done yet, though... future optimization).
+ */
+
+#ifndef __ASSEMBLY__
+/*
+ * This struct describes how the registers are laid out on the kernel stack
+ * during a syscall or other kernel entry.
+ *
+ * This structure should always be cacheline aligned on the stack.
+ * FIXME: I don't think that's the case right now. The alignment is
+ * taken care of elsewhere... head.S, process.c, etc.
+ */
+
+struct pt_regs {
+ union {
+ struct {
+ /* Named registers */
+ long sr; /* Stored in place of r0 */
+ long sp; /* r1 */
+ };
+ struct {
+ /* Old style */
+ long offset[2];
+ long gprs[30];
+ };
+ struct {
+ /* New style */
+ long gpr[32];
+ };
+ };
+ long pc;
+ long orig_gpr11; /* For restarting system calls */
+ long syscallno; /* Syscall number (used by strace) */
+ long dummy; /* Cheap alignment fix */
+};
+#endif /* __ASSEMBLY__ */
+
+/* TODO: Rename this to REDZONE because that's what it is */
+#define STACK_FRAME_OVERHEAD 128 /* size of minimum stack frame */
+
+#define instruction_pointer(regs) ((regs)->pc)
+#define user_mode(regs) (((regs)->sr & SPR_SR_SM) == 0)
+#define user_stack_pointer(regs) ((unsigned long)(regs)->sp)
+#define profile_pc(regs) instruction_pointer(regs)
+
+/*
+ * Offsets used by 'ptrace' system call interface.
+ */
+#define PT_SR 0
+#define PT_SP 4
+#define PT_GPR2 8
+#define PT_GPR3 12
+#define PT_GPR4 16
+#define PT_GPR5 20
+#define PT_GPR6 24
+#define PT_GPR7 28
+#define PT_GPR8 32
+#define PT_GPR9 36
+#define PT_GPR10 40
+#define PT_GPR11 44
+#define PT_GPR12 48
+#define PT_GPR13 52
+#define PT_GPR14 56
+#define PT_GPR15 60
+#define PT_GPR16 64
+#define PT_GPR17 68
+#define PT_GPR18 72
+#define PT_GPR19 76
+#define PT_GPR20 80
+#define PT_GPR21 84
+#define PT_GPR22 88
+#define PT_GPR23 92
+#define PT_GPR24 96
+#define PT_GPR25 100
+#define PT_GPR26 104
+#define PT_GPR27 108
+#define PT_GPR28 112
+#define PT_GPR29 116
+#define PT_GPR30 120
+#define PT_GPR31 124
+#define PT_PC 128
+#define PT_ORIG_GPR11 132
+#define PT_SYSCALLNO 136
+
+#endif /* __KERNEL__ */
+
+#endif /* __ASM_OPENRISC_PTRACE_H */
diff --git a/arch/openrisc/kernel/ptrace.c b/arch/openrisc/kernel/ptrace.c
new file mode 100644
index 000000000000..656b94beab89
--- /dev/null
+++ b/arch/openrisc/kernel/ptrace.c
@@ -0,0 +1,211 @@
+/*
+ * 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>
+#include <asm/system.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,
+ &regs->pc, 4*32, 4*33);
+ if (!ret)
+ ret = user_regset_copyout(&pos, &count, &kbuf, &ubuf,
+ &regs->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,
+ &regs->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;
+
+ /* Are these regs right??? */
+ if (unlikely(current->audit_context))
+ audit_syscall_entry(audit_arch(), regs->syscallno,
+ regs->gpr[3], regs->gpr[4],
+ regs->gpr[5], regs->gpr[6]);
+
+ return ret ? : regs->syscallno;
+}
+
+asmlinkage void do_syscall_trace_leave(struct pt_regs *regs)
+{
+ int step;
+
+ if (unlikely(current->audit_context))
+ audit_syscall_exit(AUDITSC_RESULT(regs->gpr[11]),
+ regs->gpr[11]);
+
+ step = test_thread_flag(TIF_SINGLESTEP);
+ if (step || test_thread_flag(TIF_SYSCALL_TRACE))
+ tracehook_report_syscall_exit(regs, step);
+}
OpenPOWER on IntegriCloud