Merge master.kernel.org:/pub/scm/linux/kernel/git/acme/net-2.6

[pandora-kernel.git] / include / asm-i386 / ptrace.h

diff --git a/include/asm-i386/ptrace.h b/include/asm-i386/ptrace.h
index eef9f93..7e0f294 100644 (file)
--- a/include/asm-i386/ptrace.h
+++ b/include/asm-i386/ptrace.h
@@ -55,16 +55,33 @@ struct pt_regs {
 #define PTRACE_SET_THREAD_AREA    26
 
 #ifdef __KERNEL__
+
+#include <asm/vm86.h>
+
 struct task_struct;
 extern void send_sigtrap(struct task_struct *tsk, struct pt_regs *regs, int error_code);
-#define user_mode(regs)                (3 & (regs)->xcs)
-#define user_mode_vm(regs)     ((VM_MASK & (regs)->eflags) || user_mode(regs))
+
+/*
+ * user_mode_vm(regs) determines whether a register set came from user mode.
+ * This is true if V8086 mode was enabled OR if the register set was from
+ * protected mode with RPL-3 CS value.  This tricky test checks that with
+ * one comparison.  Many places in the kernel can bypass this full check
+ * if they have already ruled out V8086 mode, so user_mode(regs) can be used.
+ */
+static inline int user_mode(struct pt_regs *regs)
+{
+       return (regs->xcs & 3) != 0;
+}
+static inline int user_mode_vm(struct pt_regs *regs)
+{
+       return ((regs->xcs & 3) | (regs->eflags & VM_MASK)) != 0;
+}
 #define instruction_pointer(regs) ((regs)->eip)
 #if defined(CONFIG_SMP) && defined(CONFIG_FRAME_POINTER)
 extern unsigned long profile_pc(struct pt_regs *regs);
 #else
 #define profile_pc(regs) instruction_pointer(regs)
 #endif
-#endif
+#endif /* __KERNEL__ */
 
 #endif