m68k/uaccess: Fix asm constraints for userspace access
When compiling a MMU kernel with CPU_HAS_ADDRESS_SPACES=n (e.g. "MMU=y
allnoconfig": "echo CONFIG_MMU=y > allno.config && make KCONFIG_ALLCONFIG=1
allnoconfig"), we use plain "move" instead of "moves", and I got:
CC arch/m68k/lib/uaccess.o
{standard input}: Assembler messages:
{standard input}:47: Error: operands mismatch -- statement `move.b %a0,(%a1)' ignored
This happens because plain "move" doesn't support byte transfers between
memory and address registers, while "moves" does.
Fix the asm constraints for __generic_copy_from_user(),
__generic_copy_to_user(), and __clear_user() to only use data registers
when accessing userspace.
Also, relax the asm constraints for 16-bit userspace accesses in
__put_user() and __get_user(), as both "move" and "moves" do support
such transfers between memory and address registers.
Signed-off-by: Geert Uytterhoeven <geert@linux-m68k.org>
diff --git a/arch/m68k/include/asm/uaccess_mm.h b/arch/m68k/include/asm/uaccess_mm.h
index 472c891..15901db 100644
--- a/arch/m68k/include/asm/uaccess_mm.h
+++ b/arch/m68k/include/asm/uaccess_mm.h
@@ -90,7 +90,7 @@
__put_user_asm(__pu_err, __pu_val, ptr, b, d, -EFAULT); \
break; \
case 2: \
- __put_user_asm(__pu_err, __pu_val, ptr, w, d, -EFAULT); \
+ __put_user_asm(__pu_err, __pu_val, ptr, w, r, -EFAULT); \
break; \
case 4: \
__put_user_asm(__pu_err, __pu_val, ptr, l, r, -EFAULT); \
@@ -158,7 +158,7 @@
__get_user_asm(__gu_err, x, ptr, u8, b, d, -EFAULT); \
break; \
case 2: \
- __get_user_asm(__gu_err, x, ptr, u16, w, d, -EFAULT); \
+ __get_user_asm(__gu_err, x, ptr, u16, w, r, -EFAULT); \
break; \
case 4: \
__get_user_asm(__gu_err, x, ptr, u32, l, r, -EFAULT); \
@@ -245,7 +245,7 @@
__get_user_asm(res, *(u8 *)to, (u8 __user *)from, u8, b, d, 1);
break;
case 2:
- __get_user_asm(res, *(u16 *)to, (u16 __user *)from, u16, w, d, 2);
+ __get_user_asm(res, *(u16 *)to, (u16 __user *)from, u16, w, r, 2);
break;
case 3:
__constant_copy_from_user_asm(res, to, from, tmp, 3, w, b,);
@@ -326,7 +326,7 @@
__put_user_asm(res, *(u8 *)from, (u8 __user *)to, b, d, 1);
break;
case 2:
- __put_user_asm(res, *(u16 *)from, (u16 __user *)to, w, d, 2);
+ __put_user_asm(res, *(u16 *)from, (u16 __user *)to, w, r, 2);
break;
case 3:
__constant_copy_to_user_asm(res, to, from, tmp, 3, w, b,);