patch-1.3.45 linux/include/asm-ppc/ptrace.h

• Lines: 53
• Date: Sat Nov 25 19:49:06 1995
• Orig file: v1.3.44/linux/include/asm-ppc/ptrace.h
• Orig date: Thu Jan 1 02:00:00 1970

diff -u --recursive --new-file v1.3.44/linux/include/asm-ppc/ptrace.h linux/include/asm-ppc/ptrace.h
@@ -0,0 +1,52 @@
+#ifndef _PPC_PTRACE_H
+#define _PPC_PTRACE_H
+
+
+/*
+ * This struct defines the way the registers are stored on the
+ * kernel stack during a system call or other kernel entry.
+ * Note: the "_overhead" and "_underhead" spaces are stack locations
+ * used by called routines.  Because of the way the PowerPC ABI
+ * specifies the function prologue/epilogue, registers can be
+ * saved in stack locations which are below the current stack
+ * pointer (_underhead).  If an interrupt occurs during this
+ * [albeit] small time interval, registers which were saved on
+ * the stack could be trashed by the interrupt save code.  The
+ * "_underhead" leaves a hole just in case this happens.  It also
+ * wastes 80 bytes of stack if it doesn't!  Similarly, the called
+ * routine stores some information "above" the stack pointer before
+ * if gets adjusted.  This is covered by the "_overhead" field
+ * and [thankfully] is not totally wasted.
+ *
+ */
+
+struct pt_regs {
+	unsigned long _overhead[14]; /* Callee's SP,LR,params */
+	unsigned long gpr[32];
+	unsigned long nip;
+	unsigned long msr;
+	unsigned long ctr;
+	unsigned long link;
+	unsigned long ccr;
+	unsigned long xer;
+	unsigned long dar;	/* Fault registers */
+	unsigned long dsisr;
+	unsigned long hash1, hash2;
+	unsigned long imiss, dmiss;
+	unsigned long icmp, dcmp;
+	unsigned long orig_gpr3; /* Used for restarting system calls */
+	unsigned long result;    /* Result of a system call */
+	double        fpr[4];    /* Caution! Only FP0-FP3 save on interrupts */
+	double        fpcsr;
+	unsigned long trap;	/* Reason for being here */
+	unsigned long marker;	/* Should have DEADDEAD */
+	unsigned long _underhead[20]; /* Callee's register save area */
+	unsigned long edx;	/* for binfmt_elf.c which wants edx */
+};
+
+#define instruction_pointer(regs) ((regs)->nip)
+#define user_mode(regs) ((regs)->msr & 0x4000)
+extern void show_regs(struct pt_regs *);
+
+#endif
+