m68k: get rid of zeroing

Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>

diff --git a/arch/m68k/include/asm/uaccess_mm.h b/arch/m68k/include/asm/uaccess_mm.h
index 23be968a53fd2f26ab6e0b225ceb12dee572e62b..931bbba449e232f07ee907e87be4c94d6f32f129 100644 (file)
--- a/arch/m68k/include/asm/uaccess_mm.h
+++ b/arch/m68k/include/asm/uaccess_mm.h
@@ -179,39 +179,55 @@ asm volatile ("\n"                                        \
 unsigned long __generic_copy_from_user(void *to, const void __user *from, unsigned long n);
 unsigned long __generic_copy_to_user(void __user *to, const void *from, unsigned long n);
 
-#define __constant_copy_from_user_asm(res, to, from, tmp, n, s1, s2, s3)\
+#define __suffix0
+#define __suffix1 b
+#define __suffix2 w
+#define __suffix4 l
+
+#define ____constant_copy_from_user_asm(res, to, from, tmp, n1, n2, n3, s1, s2, s3)\
        asm volatile ("\n"                                              \
                "1:     "MOVES"."#s1"   (%2)+,%3\n"                     \
                "       move."#s1"      %3,(%1)+\n"                     \
+               "       .ifnc   \""#s2"\",\"\"\n"                       \
                "2:     "MOVES"."#s2"   (%2)+,%3\n"                     \
                "       move."#s2"      %3,(%1)+\n"                     \
                "       .ifnc   \""#s3"\",\"\"\n"                       \
                "3:     "MOVES"."#s3"   (%2)+,%3\n"                     \
                "       move."#s3"      %3,(%1)+\n"                     \
                "       .endif\n"                                       \
+               "       .endif\n"                                       \
                "4:\n"                                                  \
                "       .section __ex_table,\"a\"\n"                    \
                "       .align  4\n"                                    \
                "       .long   1b,10f\n"                               \
+               "       .ifnc   \""#s2"\",\"\"\n"                       \
                "       .long   2b,20f\n"                               \
                "       .ifnc   \""#s3"\",\"\"\n"                       \
                "       .long   3b,30f\n"                               \
                "       .endif\n"                                       \
+               "       .endif\n"                                       \
                "       .previous\n"                                    \
                "\n"                                                    \
                "       .section .fixup,\"ax\"\n"                       \
                "       .even\n"                                        \
-               "10:    clr."#s1"       (%1)+\n"                        \
-               "20:    clr."#s2"       (%1)+\n"                        \
+               "10:    addq.l #"#n1",%0\n"                             \
+               "       .ifnc   \""#s2"\",\"\"\n"                       \
+               "20:    addq.l #"#n2",%0\n"                             \
                "       .ifnc   \""#s3"\",\"\"\n"                       \
-               "30:    clr."#s3"       (%1)+\n"                        \
+               "30:    addq.l #"#n3",%0\n"                             \
+               "       .endif\n"                                       \
                "       .endif\n"                                       \
-               "       moveq.l #"#n",%0\n"                             \
                "       jra     4b\n"                                   \
                "       .previous\n"                                    \
                : "+d" (res), "+&a" (to), "+a" (from), "=&d" (tmp)      \
                : : "memory")
 
+#define ___constant_copy_from_user_asm(res, to, from, tmp, n1, n2, n3, s1, s2, s3)\
+       ____constant_copy_from_user_asm(res, to, from, tmp, n1, n2, n3, s1, s2, s3)
+#define __constant_copy_from_user_asm(res, to, from, tmp, n1, n2, n3)  \
+       ___constant_copy_from_user_asm(res, to, from, tmp, n1, n2, n3,  \
+                                       __suffix##n1, __suffix##n2, __suffix##n3)
+
 static __always_inline unsigned long
 __constant_copy_from_user(void *to, const void __user *from, unsigned long n)
 {
@@ -219,37 +235,37 @@ __constant_copy_from_user(void *to, const void __user *from, unsigned long n)
 
        switch (n) {
        case 1:
-               __get_user_asm(res, *(u8 *)to, (u8 __user *)from, u8, b, d, 1);
+               __constant_copy_from_user_asm(res, to, from, tmp, 1, 0, 0);
                break;
        case 2:
-               __get_user_asm(res, *(u16 *)to, (u16 __user *)from, u16, w, r, 2);
+               __constant_copy_from_user_asm(res, to, from, tmp, 2, 0, 0);
                break;
        case 3:
-               __constant_copy_from_user_asm(res, to, from, tmp, 3, w, b,);
+               __constant_copy_from_user_asm(res, to, from, tmp, 2, 1, 0);
                break;
        case 4:
-               __get_user_asm(res, *(u32 *)to, (u32 __user *)from, u32, l, r, 4);
+               __constant_copy_from_user_asm(res, to, from, tmp, 4, 0, 0);
                break;
        case 5:
-               __constant_copy_from_user_asm(res, to, from, tmp, 5, l, b,);
+               __constant_copy_from_user_asm(res, to, from, tmp, 4, 1, 0);
                break;
        case 6:
-               __constant_copy_from_user_asm(res, to, from, tmp, 6, l, w,);
+               __constant_copy_from_user_asm(res, to, from, tmp, 4, 2, 0);
                break;
        case 7:
-               __constant_copy_from_user_asm(res, to, from, tmp, 7, l, w, b);
+               __constant_copy_from_user_asm(res, to, from, tmp, 4, 2, 1);
                break;
        case 8:
-               __constant_copy_from_user_asm(res, to, from, tmp, 8, l, l,);
+               __constant_copy_from_user_asm(res, to, from, tmp, 4, 4, 0);
                break;
        case 9:
-               __constant_copy_from_user_asm(res, to, from, tmp, 9, l, l, b);
+               __constant_copy_from_user_asm(res, to, from, tmp, 4, 4, 1);
                break;
        case 10:
-               __constant_copy_from_user_asm(res, to, from, tmp, 10, l, l, w);
+               __constant_copy_from_user_asm(res, to, from, tmp, 4, 4, 2);
                break;
        case 12:
-               __constant_copy_from_user_asm(res, to, from, tmp, 12, l, l, l);
+               __constant_copy_from_user_asm(res, to, from, tmp, 4, 4, 4);
                break;
        default:
                /* we limit the inlined version to 3 moves */
@@ -353,7 +369,14 @@ __constant_copy_to_user(void __user *to, const void *from, unsigned long n)
 #define __copy_to_user_inatomic                __copy_to_user
 #define __copy_from_user_inatomic      __copy_from_user
 
-#define copy_from_user(to, from, n)    __copy_from_user(to, from, n)
+static inline unsigned long
+copy_from_user(void *to, const void __user *from, unsigned long n)
+{
+       unsigned long res = __copy_from_user_inatomic(to, from, n);
+       if (unlikely(res))
+               memset(to + (n - res), 0, res);
+       return res;
+}
 #define copy_to_user(to, from, n)      __copy_to_user(to, from, n)
 
 #define user_addr_max() \

diff --git a/arch/m68k/lib/uaccess.c b/arch/m68k/lib/uaccess.c
index a76b73abaf6491d01feccd6ac750ac2d65456355..7646e461aa6207461422bc00f4be7fb4e3b50e7b 100644 (file)
--- a/arch/m68k/lib/uaccess.c
+++ b/arch/m68k/lib/uaccess.c
@@ -30,19 +30,13 @@ unsigned long __generic_copy_from_user(void *to, const void __user *from,
                "6:\n"
                "       .section .fixup,\"ax\"\n"
                "       .even\n"
-               "10:    move.l  %0,%3\n"
-               "7:     clr.l   (%2)+\n"
-               "       subq.l  #1,%3\n"
-               "       jne     7b\n"
-               "       lsl.l   #2,%0\n"
+               "10:    lsl.l   #2,%0\n"
                "       btst    #1,%5\n"
                "       jeq     8f\n"
-               "30:    clr.w   (%2)+\n"
-               "       addq.l  #2,%0\n"
+               "30:    addq.l  #2,%0\n"
                "8:     btst    #0,%5\n"
                "       jeq     6b\n"
-               "50:    clr.b   (%2)+\n"
-               "       addq.l  #1,%0\n"
+               "50:    addq.l  #1,%0\n"
                "       jra     6b\n"
                "       .previous\n"
                "\n"