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-rw-r--r--arch/alpha/include/asm/ptrace.h83
1 files changed, 83 insertions, 0 deletions
diff --git a/arch/alpha/include/asm/ptrace.h b/arch/alpha/include/asm/ptrace.h
new file mode 100644
index 00000000000..32c7a5cddd5
--- /dev/null
+++ b/arch/alpha/include/asm/ptrace.h
@@ -0,0 +1,83 @@
+#ifndef _ASMAXP_PTRACE_H
+#define _ASMAXP_PTRACE_H
+
+
+/*
+ * This struct defines the way the registers are stored on the
+ * kernel stack during a system call or other kernel entry
+ *
+ * NOTE! I want to minimize the overhead of system calls, so this
+ * struct has as little information as possible. I does not have
+ *
+ * - floating point regs: the kernel doesn't change those
+ * - r9-15: saved by the C compiler
+ *
+ * This makes "fork()" and "exec()" a bit more complex, but should
+ * give us low system call latency.
+ */
+
+struct pt_regs {
+ unsigned long r0;
+ unsigned long r1;
+ unsigned long r2;
+ unsigned long r3;
+ unsigned long r4;
+ unsigned long r5;
+ unsigned long r6;
+ unsigned long r7;
+ unsigned long r8;
+ unsigned long r19;
+ unsigned long r20;
+ unsigned long r21;
+ unsigned long r22;
+ unsigned long r23;
+ unsigned long r24;
+ unsigned long r25;
+ unsigned long r26;
+ unsigned long r27;
+ unsigned long r28;
+ unsigned long hae;
+/* JRP - These are the values provided to a0-a2 by PALcode */
+ unsigned long trap_a0;
+ unsigned long trap_a1;
+ unsigned long trap_a2;
+/* These are saved by PAL-code: */
+ unsigned long ps;
+ unsigned long pc;
+ unsigned long gp;
+ unsigned long r16;
+ unsigned long r17;
+ unsigned long r18;
+};
+
+/*
+ * This is the extended stack used by signal handlers and the context
+ * switcher: it's pushed after the normal "struct pt_regs".
+ */
+struct switch_stack {
+ unsigned long r9;
+ unsigned long r10;
+ unsigned long r11;
+ unsigned long r12;
+ unsigned long r13;
+ unsigned long r14;
+ unsigned long r15;
+ unsigned long r26;
+ unsigned long fp[32]; /* fp[31] is fpcr */
+};
+
+#ifdef __KERNEL__
+
+#define user_mode(regs) (((regs)->ps & 8) != 0)
+#define instruction_pointer(regs) ((regs)->pc)
+#define profile_pc(regs) instruction_pointer(regs)
+extern void show_regs(struct pt_regs *);
+
+#define task_pt_regs(task) \
+ ((struct pt_regs *) (task_stack_page(task) + 2*PAGE_SIZE) - 1)
+
+#define force_successful_syscall_return() (task_pt_regs(current)->r0 = 0)
+
+#endif
+
+#endif