Blackfin: initial tracehook support
Signed-off-by: Mike Frysinger <vapier@gentoo.org>
diff --git a/arch/blackfin/include/asm/ptrace.h b/arch/blackfin/include/asm/ptrace.h
index c1aebdb..aaa1c6c 100644
--- a/arch/blackfin/include/asm/ptrace.h
+++ b/arch/blackfin/include/asm/ptrace.h
@@ -24,6 +24,8 @@
#ifndef __ASSEMBLY__
+struct task_struct;
+
/* this struct defines the way the registers are stored on the
stack during a system call. */
@@ -101,9 +103,30 @@
master interrupt enable. */
#define user_mode(regs) (!(((regs)->ipend & ~0x10) & (((regs)->ipend & ~0x10) - 1)))
#define instruction_pointer(regs) ((regs)->pc)
+#define user_stack_pointer(regs) ((regs)->usp)
#define profile_pc(regs) instruction_pointer(regs)
extern void show_regs(struct pt_regs *);
+#define arch_has_single_step() (1)
+extern void user_enable_single_step(struct task_struct *child);
+extern void user_disable_single_step(struct task_struct *child);
+/* common code demands this function */
+#define ptrace_disable(child) user_disable_single_step(child)
+
+/*
+ * Get the address of the live pt_regs for the specified task.
+ * These are saved onto the top kernel stack when the process
+ * is not running.
+ *
+ * Note: if a user thread is execve'd from kernel space, the
+ * kernel stack will not be empty on entry to the kernel, so
+ * ptracing these tasks will fail.
+ */
+#define task_pt_regs(task) \
+ (struct pt_regs *) \
+ ((unsigned long)task_stack_page(task) + \
+ (THREAD_SIZE - sizeof(struct pt_regs)))
+
#endif /* __KERNEL__ */
#endif /* __ASSEMBLY__ */
diff --git a/arch/blackfin/include/asm/syscall.h b/arch/blackfin/include/asm/syscall.h
new file mode 100644
index 0000000..4921a48
--- /dev/null
+++ b/arch/blackfin/include/asm/syscall.h
@@ -0,0 +1,96 @@
+/*
+ * Magic syscall break down functions
+ *
+ * Copyright 2010 Analog Devices Inc.
+ *
+ * Licensed under the GPL-2 or later.
+ */
+
+#ifndef __ASM_BLACKFIN_SYSCALL_H__
+#define __ASM_BLACKFIN_SYSCALL_H__
+
+/*
+ * Blackfin syscalls are simple:
+ * enter:
+ * p0: syscall number
+ * r{0,1,2,3,4,5}: syscall args 0,1,2,3,4,5
+ * exit:
+ * r0: return/error value
+ */
+
+#include <linux/err.h>
+#include <linux/sched.h>
+#include <asm/ptrace.h>
+
+static inline long
+syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
+{
+ return regs->p0;
+}
+
+static inline void
+syscall_rollback(struct task_struct *task, struct pt_regs *regs)
+{
+ regs->p0 = regs->orig_p0;
+}
+
+static inline long
+syscall_get_error(struct task_struct *task, struct pt_regs *regs)
+{
+ return IS_ERR_VALUE(regs->r0) ? regs->r0 : 0;
+}
+
+static inline long
+syscall_get_return_value(struct task_struct *task, struct pt_regs *regs)
+{
+ return regs->r0;
+}
+
+static inline void
+syscall_set_return_value(struct task_struct *task, struct pt_regs *regs,
+ int error, long val)
+{
+ regs->r0 = error ? -error : val;
+}
+
+/**
+ * syscall_get_arguments()
+ * @task: unused
+ * @regs: the register layout to extract syscall arguments from
+ * @i: first syscall argument to extract
+ * @n: number of syscall arguments to extract
+ * @args: array to return the syscall arguments in
+ *
+ * args[0] gets i'th argument, args[n - 1] gets the i+n-1'th argument
+ */
+static inline void
+syscall_get_arguments(struct task_struct *task, struct pt_regs *regs,
+ unsigned int i, unsigned int n, unsigned long *args)
+{
+ /*
+ * Assume the ptrace layout doesn't change -- r5 is first in memory,
+ * then r4, ..., then r0. So we simply reverse the ptrace register
+ * array in memory to store into the args array.
+ */
+ long *aregs = ®s->r0 - i;
+
+ BUG_ON(i > 5 || i + n > 6);
+
+ while (n--)
+ *args++ = *aregs--;
+}
+
+/* See syscall_get_arguments() comments */
+static inline void
+syscall_set_arguments(struct task_struct *task, struct pt_regs *regs,
+ unsigned int i, unsigned int n, const unsigned long *args)
+{
+ long *aregs = ®s->r0 - i;
+
+ BUG_ON(i > 5 || i + n > 6);
+
+ while (n--)
+ *aregs-- = *args++;
+}
+
+#endif