sh: break out unaligned sign extension code

Break out the sign extension code since it's used in multiple places.

Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

diff --git a/arch/sh/kernel/traps_32.c b/arch/sh/kernel/traps_32.c
index 2e58f7a..7154a7b 100644 (file)
--- a/arch/sh/kernel/traps_32.c
+++ b/arch/sh/kernel/traps_32.c
@@ -147,6 +147,21 @@ static int die_if_no_fixup(const char * str, struct pt_regs * regs, long err)
        return -EFAULT;
 }
 
+static inline void sign_extend(unsigned int count, unsigned char *dst)
+{
+#ifdef __LITTLE_ENDIAN__
+       if ((count == 2) && dst[1] & 0x80) {
+               dst[2] = 0xff;
+               dst[3] = 0xff;
+       }
+#else
+       if ((count == 2) && dst[2] & 0x80) {
+               dst[0] = 0xff;
+               dst[1] = 0xff;
+       }
+#endif
+}
+
 /*
  * handle an instruction that does an unaligned memory access by emulating the
  * desired behaviour
@@ -178,25 +193,13 @@ static int handle_unaligned_ins(u16 instruction, struct pt_regs *regs)
                        dst = (unsigned char*) rn;
                        *(unsigned long*)dst = 0;
 
-#ifdef __LITTLE_ENDIAN__
-                       if (copy_from_user(dst, src, count))
-                               goto fetch_fault;
-
-                       if ((count == 2) && dst[1] & 0x80) {
-                               dst[2] = 0xff;
-                               dst[3] = 0xff;
-                       }
-#else
+#if !defined(__LITTLE_ENDIAN__)
                        dst += 4-count;
-
-                       if (__copy_user(dst, src, count))
+#endif
+                       if (copy_from_user(dst, src, count))
                                goto fetch_fault;
 
-                       if ((count == 2) && dst[2] & 0x80) {
-                               dst[0] = 0xff;
-                               dst[1] = 0xff;
-                       }
-#endif
+                       sign_extend(count, dst);
                } else {
                        /* to memory */
                        src = (unsigned char*) rm;
@@ -253,25 +256,12 @@ static int handle_unaligned_ins(u16 instruction, struct pt_regs *regs)
                dst = (unsigned char*) rn;
                *(unsigned long*)dst = 0;
 
-#ifdef __LITTLE_ENDIAN__
-               if (copy_from_user(dst, src, count))
-                       goto fetch_fault;
-
-               if ((count == 2) && dst[1] & 0x80) {
-                       dst[2] = 0xff;
-                       dst[3] = 0xff;
-               }
-#else
+#if !defined(__LITTLE_ENDIAN__)
                dst += 4-count;
-
+#endif
                if (copy_from_user(dst, src, count))
                        goto fetch_fault;
-
-               if ((count == 2) && dst[2] & 0x80) {
-                       dst[0] = 0xff;
-                       dst[1] = 0xff;
-               }
-#endif
+               sign_extend(count, dst);
                ret = 0;
                break;
 
@@ -299,21 +289,9 @@ static int handle_unaligned_ins(u16 instruction, struct pt_regs *regs)
 #if !defined(__LITTLE_ENDIAN__)
                        dst += 2;
 #endif
-
                        if (copy_from_user(dst, src, 2))
                                goto fetch_fault;
-
-#ifdef __LITTLE_ENDIAN__
-                       if (dst[1] & 0x80) {
-                               dst[2] = 0xff;
-                               dst[3] = 0xff;
-                       }
-#else
-                       if (dst[2] & 0x80) {
-                               dst[0] = 0xff;
-                               dst[1] = 0xff;
-                       }
-#endif
+                       sign_extend(2, dst);
                        ret = 0;
                        break;
                }