mips: define syscall_get_error()

syscall_get_error() is required to be implemented on all architectures
in addition to already implemented syscall_get_nr(),
syscall_get_arguments(), syscall_get_return_value(), and
syscall_get_arch() functions in order to extend the generic ptrace API
with PTRACE_GET_SYSCALL_INFO request.

Link: http://lkml.kernel.org/r/[email protected]
Signed-off-by: Dmitry V. Levin <[email protected]>
Acked-by: Paul Burton <[email protected]>
Cc: Elvira Khabirova <[email protected]>
Cc: Eugene Syromyatnikov <[email protected]>
Cc: Ralf Baechle <[email protected]>
Cc: James Hogan <[email protected]>
Cc: Oleg Nesterov <[email protected]>
Cc: Andy Lutomirski <[email protected]>
Cc: Benjamin Herrenschmidt <[email protected]>
Cc: Greentime Hu <[email protected]>
Cc: Helge Deller <[email protected]>	[parisc]
Cc: James E.J. Bottomley <[email protected]>
Cc: kbuild test robot <[email protected]>
Cc: Kees Cook <[email protected]>
Cc: Michael Ellerman <[email protected]>
Cc: Paul Mackerras <[email protected]>
Cc: Richard Kuo <[email protected]>
Cc: Shuah Khan <[email protected]>
Cc: Vincent Chen <[email protected]>
Signed-off-by: Andrew Morton <[email protected]>
Signed-off-by: Linus Torvalds <[email protected]>

1 files changed, 6 insertions, 0 deletions

diff --git a/arch/mips/include/asm/syscall.h b/arch/mips/include/asm/syscall.h
index acf80ae0a430..83bb439597d8 100644
--- a/arch/mips/include/asm/syscall.h
+++ b/arch/mips/include/asm/syscall.h
@@ -89,6 +89,12 @@ static inline unsigned long mips_get_syscall_arg(unsigned long *arg,
 	unreachable();
 }
 
+static inline long syscall_get_error(struct task_struct *task,
+				     struct pt_regs *regs)
+{
+	return regs->regs[7] ? -regs->regs[2] : 0;
+}
+
 static inline long syscall_get_return_value(struct task_struct *task,
 					    struct pt_regs *regs)
 {