x86: get rid of small constant size cases in raw_copy_{to,from}_user()

Very few call sites where that would be triggered remain, and none
of those is anywhere near hot enough to bother.

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

diff --git a/arch/x86/include/asm/uaccess.h b/arch/x86/include/asm/uaccess.h
index ab8eab43a8a2a056af9397c7983d892d98028c1e..1cfa33b94a1a86e8a7845b6be30ac3d87d323b10 100644 (file)
--- a/arch/x86/include/asm/uaccess.h
+++ b/arch/x86/include/asm/uaccess.h
@@ -378,18 +378,6 @@ do {                                                                       \
                     : "=r" (err), ltype(x)                             \
                     : "m" (__m(addr)), "i" (errret), "0" (err))
 
-#define __get_user_asm_nozero(x, addr, err, itype, rtype, ltype, errret)       \
-       asm volatile("\n"                                               \
-                    "1:        mov"itype" %2,%"rtype"1\n"              \
-                    "2:\n"                                             \
-                    ".section .fixup,\"ax\"\n"                         \
-                    "3:        mov %3,%0\n"                            \
-                    "  jmp 2b\n"                                       \
-                    ".previous\n"                                      \
-                    _ASM_EXTABLE_UA(1b, 3b)                            \
-                    : "=r" (err), ltype(x)                             \
-                    : "m" (__m(addr)), "i" (errret), "0" (err))
-
 /*
  * This doesn't do __uaccess_begin/end - the exception handling
  * around it must do that.

diff --git a/arch/x86/include/asm/uaccess_32.h b/arch/x86/include/asm/uaccess_32.h
index ba2dc19306303728e1cf8652a20d982dce1e4e2a..388a40660c7b517f53c5685ae28844b9b4cacb87 100644 (file)
--- a/arch/x86/include/asm/uaccess_32.h
+++ b/arch/x86/include/asm/uaccess_32.h
@@ -23,33 +23,6 @@ raw_copy_to_user(void __user *to, const void *from, unsigned long n)
 static __always_inline unsigned long
 raw_copy_from_user(void *to, const void __user *from, unsigned long n)
 {
-       if (__builtin_constant_p(n)) {
-               unsigned long ret;
-
-               switch (n) {
-               case 1:
-                       ret = 0;
-                       __uaccess_begin_nospec();
-                       __get_user_asm_nozero(*(u8 *)to, from, ret,
-                                             "b", "b", "=q", 1);
-                       __uaccess_end();
-                       return ret;
-               case 2:
-                       ret = 0;
-                       __uaccess_begin_nospec();
-                       __get_user_asm_nozero(*(u16 *)to, from, ret,
-                                             "w", "w", "=r", 2);
-                       __uaccess_end();
-                       return ret;
-               case 4:
-                       ret = 0;
-                       __uaccess_begin_nospec();
-                       __get_user_asm_nozero(*(u32 *)to, from, ret,
-                                             "l", "k", "=r", 4);
-                       __uaccess_end();
-                       return ret;
-               }
-       }
        return __copy_user_ll(to, (__force const void *)from, n);
 }
 

diff --git a/arch/x86/include/asm/uaccess_64.h b/arch/x86/include/asm/uaccess_64.h
index 5cd1caa8bc6537c8795218581118c60552128ad8..bc10e3dc64fed755dc5077bb4c6bc3c6984794f2 100644 (file)
--- a/arch/x86/include/asm/uaccess_64.h
+++ b/arch/x86/include/asm/uaccess_64.h
@@ -65,117 +65,13 @@ copy_to_user_mcsafe(void *to, const void *from, unsigned len)
 static __always_inline __must_check unsigned long
 raw_copy_from_user(void *dst, const void __user *src, unsigned long size)
 {
-       int ret = 0;
-
-       if (!__builtin_constant_p(size))
-               return copy_user_generic(dst, (__force void *)src, size);
-       switch (size) {
-       case 1:
-               __uaccess_begin_nospec();
-               __get_user_asm_nozero(*(u8 *)dst, (u8 __user *)src,
-                             ret, "b", "b", "=q", 1);
-               __uaccess_end();
-               return ret;
-       case 2:
-               __uaccess_begin_nospec();
-               __get_user_asm_nozero(*(u16 *)dst, (u16 __user *)src,
-                             ret, "w", "w", "=r", 2);
-               __uaccess_end();
-               return ret;
-       case 4:
-               __uaccess_begin_nospec();
-               __get_user_asm_nozero(*(u32 *)dst, (u32 __user *)src,
-                             ret, "l", "k", "=r", 4);
-               __uaccess_end();
-               return ret;
-       case 8:
-               __uaccess_begin_nospec();
-               __get_user_asm_nozero(*(u64 *)dst, (u64 __user *)src,
-                             ret, "q", "", "=r", 8);
-               __uaccess_end();
-               return ret;
-       case 10:
-               __uaccess_begin_nospec();
-               __get_user_asm_nozero(*(u64 *)dst, (u64 __user *)src,
-                              ret, "q", "", "=r", 10);
-               if (likely(!ret))
-                       __get_user_asm_nozero(*(u16 *)(8 + (char *)dst),
-                                      (u16 __user *)(8 + (char __user *)src),
-                                      ret, "w", "w", "=r", 2);
-               __uaccess_end();
-               return ret;
-       case 16:
-               __uaccess_begin_nospec();
-               __get_user_asm_nozero(*(u64 *)dst, (u64 __user *)src,
-                              ret, "q", "", "=r", 16);
-               if (likely(!ret))
-                       __get_user_asm_nozero(*(u64 *)(8 + (char *)dst),
-                                      (u64 __user *)(8 + (char __user *)src),
-                                      ret, "q", "", "=r", 8);
-               __uaccess_end();
-               return ret;
-       default:
-               return copy_user_generic(dst, (__force void *)src, size);
-       }
+       return copy_user_generic(dst, (__force void *)src, size);
 }
 
 static __always_inline __must_check unsigned long
 raw_copy_to_user(void __user *dst, const void *src, unsigned long size)
 {
-       int ret = 0;
-
-       if (!__builtin_constant_p(size))
-               return copy_user_generic((__force void *)dst, src, size);
-       switch (size) {
-       case 1:
-               __uaccess_begin();
-               __put_user_asm(*(u8 *)src, (u8 __user *)dst,
-                             ret, "b", "b", "iq", 1);
-               __uaccess_end();
-               return ret;
-       case 2:
-               __uaccess_begin();
-               __put_user_asm(*(u16 *)src, (u16 __user *)dst,
-                             ret, "w", "w", "ir", 2);
-               __uaccess_end();
-               return ret;
-       case 4:
-               __uaccess_begin();
-               __put_user_asm(*(u32 *)src, (u32 __user *)dst,
-                             ret, "l", "k", "ir", 4);
-               __uaccess_end();
-               return ret;
-       case 8:
-               __uaccess_begin();
-               __put_user_asm(*(u64 *)src, (u64 __user *)dst,
-                             ret, "q", "", "er", 8);
-               __uaccess_end();
-               return ret;
-       case 10:
-               __uaccess_begin();
-               __put_user_asm(*(u64 *)src, (u64 __user *)dst,
-                              ret, "q", "", "er", 10);
-               if (likely(!ret)) {
-                       asm("":::"memory");
-                       __put_user_asm(4[(u16 *)src], 4 + (u16 __user *)dst,
-                                      ret, "w", "w", "ir", 2);
-               }
-               __uaccess_end();
-               return ret;
-       case 16:
-               __uaccess_begin();
-               __put_user_asm(*(u64 *)src, (u64 __user *)dst,
-                              ret, "q", "", "er", 16);
-               if (likely(!ret)) {
-                       asm("":::"memory");
-                       __put_user_asm(1[(u64 *)src], 1 + (u64 __user *)dst,
-                                      ret, "q", "", "er", 8);
-               }
-               __uaccess_end();
-               return ret;
-       default:
-               return copy_user_generic((__force void *)dst, src, size);
-       }
+       return copy_user_generic((__force void *)dst, src, size);
 }
 
 static __always_inline __must_check