openrisc: sanitize use of orig_gpr11

The pt_regs struct had both a 'syscallno' field and an 'orig_gpr11' field
and it wasn't really clear how these were supposed to be used.  This patch
removes the syscallno field altogether and makes orig_gpr11 work more
like other architectures: keep track of syscall number in progress or
hold -1 for non-syscall exceptions.

Signed-off-by: Jonas Bonn <jonas@southpole.se>

2 files changed, 7 insertions, 6 deletions

diff --git a/arch/openrisc/include/asm/ptrace.h b/arch/openrisc/include/asm/ptrace.h
index e612ce4512c7..4651a737591d 100644
--- a/arch/openrisc/include/asm/ptrace.h
+++ b/arch/openrisc/include/asm/ptrace.h
@@ -73,9 +73,13 @@ struct pt_regs {
                 };
         };
         long  pc;
+        /* For restarting system calls:
+         * Set to syscall number for syscall exceptions,
+         * -1 for all other exceptions.
+         */
         long  orig_gpr11;       /* For restarting system calls */
-        long  syscallno;        /* Syscall number (used by strace) */
         long dummy;             /* Cheap alignment fix */
+        long dummy2;            /* Cheap alignment fix */
 };
 
 /* TODO: Rename this to REDZONE because that's what it is */
diff --git a/arch/openrisc/include/asm/syscall.h b/arch/openrisc/include/asm/syscall.h
index 9f0337055d26..b752bb67891d 100644
--- a/arch/openrisc/include/asm/syscall.h
+++ b/arch/openrisc/include/asm/syscall.h
@@ -25,7 +25,7 @@
 static inline int
 syscall_get_nr(struct task_struct *task, struct pt_regs *regs)
 {
-        return regs->syscallno ? regs->syscallno : -1;
+        return regs->orig_gpr11;
 }
 
 static inline void
@@ -50,10 +50,7 @@ static inline void
 syscall_set_return_value(struct task_struct *task, struct pt_regs *regs,
                          int error, long val)
 {
-        if (error)
-                regs->gpr[11] = -error;
-        else
-                regs->gpr[11] = val;
+        regs->gpr[11] = (long) error ?: val;
 }
 
 static inline void