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authorMagnus Damm <magnus.damm@gmail.com>2008-02-07 00:02:50 +0900
committerPaul Mundt <lethal@linux-sh.org>2008-02-14 14:22:07 +0900
commit86c0179c9307bd600a96a44d623814c33bdbe0f0 (patch)
tree6651026da498831b60c4c3694781b8ac9d44facf
parent1cfb629cfa4a8d9b65c0f60c65ec731bde82d60c (diff)
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>
-rw-r--r--arch/sh/kernel/traps_32.c68
1 files changed, 23 insertions, 45 deletions
diff --git a/arch/sh/kernel/traps_32.c b/arch/sh/kernel/traps_32.c
index 2e58f7a6b74..7154a7b2135 100644
--- 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;
}