From 4df3715efe5ed1e77344c6d5dcbfd75017a2f8b5 Mon Sep 17 00:00:00 2001 From: Al Viro Date: Mon, 20 Mar 2017 20:45:41 -0400 Subject: mn10300: get rid of zeroing Signed-off-by: Al Viro --- arch/mn10300/include/asm/uaccess.h | 150 ++++--------------------------------- arch/mn10300/lib/usercopy.c | 11 +-- 2 files changed, 20 insertions(+), 141 deletions(-) (limited to 'arch') diff --git a/arch/mn10300/include/asm/uaccess.h b/arch/mn10300/include/asm/uaccess.h index 2eeaa8c5d92c..1c35be3d8fef 100644 --- a/arch/mn10300/include/asm/uaccess.h +++ b/arch/mn10300/include/asm/uaccess.h @@ -275,55 +275,19 @@ do { \ } \ } while (0) -#define __copy_user_zeroing(to, from, size) \ -do { \ - if (size) { \ - void *__to = to; \ - const void *__from = from; \ - int w; \ - asm volatile( \ - "0: movbu (%0),%3;\n" \ - "1: movbu %3,(%1);\n" \ - " inc %0;\n" \ - " inc %1;\n" \ - " add -1,%2;\n" \ - " bne 0b;\n" \ - "2:\n" \ - " .section .fixup,\"ax\"\n" \ - "3:\n" \ - " mov %2,%0\n" \ - " clr %3\n" \ - "4: movbu %3,(%1);\n" \ - " inc %1;\n" \ - " add -1,%2;\n" \ - " bne 4b;\n" \ - " mov %0,%2\n" \ - " jmp 2b\n" \ - " .previous\n" \ - " .section __ex_table,\"a\"\n" \ - " .balign 4\n" \ - " .long 0b,3b\n" \ - " .long 1b,3b\n" \ - " .previous\n" \ - : "=a"(__from), "=a"(__to), "=r"(size), "=&r"(w)\ - : "0"(__from), "1"(__to), "2"(size) \ - : "cc", "memory"); \ - } \ -} while (0) - /* We let the __ versions of copy_from/to_user inline, because they're often * used in fast paths and have only a small space overhead. */ static inline -unsigned long __generic_copy_from_user_nocheck(void *to, const void *from, +unsigned long __copy_from_user_inatomic(void *to, const void __user *from, unsigned long n) { - __copy_user_zeroing(to, from, n); + __copy_user(to, from, n); return n; } static inline -unsigned long __generic_copy_to_user_nocheck(void *to, const void *from, +unsigned long __copy_to_user_inatomic(void __user *to, const void *from, unsigned long n) { __copy_user(to, from, n); @@ -331,110 +295,24 @@ unsigned long __generic_copy_to_user_nocheck(void *to, const void *from, } -#if 0 -#error "don't use - these macros don't increment to & from pointers" -/* Optimize just a little bit when we know the size of the move. */ -#define __constant_copy_user(to, from, size) \ -do { \ - asm volatile( \ - " mov %0,a0;\n" \ - "0: movbu (%1),d3;\n" \ - "1: movbu d3,(%2);\n" \ - " add -1,a0;\n" \ - " bne 0b;\n" \ - "2:;" \ - ".section .fixup,\"ax\"\n" \ - "3: jmp 2b\n" \ - ".previous\n" \ - ".section __ex_table,\"a\"\n" \ - " .balign 4\n" \ - " .long 0b,3b\n" \ - " .long 1b,3b\n" \ - ".previous" \ - : \ - : "d"(size), "d"(to), "d"(from) \ - : "d3", "a0"); \ -} while (0) - -/* Optimize just a little bit when we know the size of the move. */ -#define __constant_copy_user_zeroing(to, from, size) \ -do { \ - asm volatile( \ - " mov %0,a0;\n" \ - "0: movbu (%1),d3;\n" \ - "1: movbu d3,(%2);\n" \ - " add -1,a0;\n" \ - " bne 0b;\n" \ - "2:;" \ - ".section .fixup,\"ax\"\n" \ - "3: jmp 2b\n" \ - ".previous\n" \ - ".section __ex_table,\"a\"\n" \ - " .balign 4\n" \ - " .long 0b,3b\n" \ - " .long 1b,3b\n" \ - ".previous" \ - : \ - : "d"(size), "d"(to), "d"(from) \ - : "d3", "a0"); \ -} while (0) - -static inline -unsigned long __constant_copy_to_user(void *to, const void *from, - unsigned long n) -{ - if (access_ok(VERIFY_WRITE, to, n)) - __constant_copy_user(to, from, n); - return n; -} - -static inline -unsigned long __constant_copy_from_user(void *to, const void *from, - unsigned long n) -{ - if (access_ok(VERIFY_READ, from, n)) - __constant_copy_user_zeroing(to, from, n); - return n; -} +extern unsigned long __generic_copy_to_user(void __user *, const void *, + unsigned long); +extern unsigned long __generic_copy_from_user(void *, const void __user *, + unsigned long); -static inline -unsigned long __constant_copy_to_user_nocheck(void *to, const void *from, - unsigned long n) +static inline unsigned long __copy_to_user(void __user *to, const void *from, + unsigned long n) { - __constant_copy_user(to, from, n); - return n; + might_fault(); + return __copy_to_user_inatomic(to, from, n); } -static inline -unsigned long __constant_copy_from_user_nocheck(void *to, const void *from, +static inline unsigned long __copy_from_user(void *to, const void __user *from, unsigned long n) { - __constant_copy_user_zeroing(to, from, n); - return n; + might_fault(); + return __copy_from_user_inatomic(to, from, n); } -#endif - -extern unsigned long __generic_copy_to_user(void __user *, const void *, - unsigned long); -extern unsigned long __generic_copy_from_user(void *, const void __user *, - unsigned long); - -#define __copy_to_user_inatomic(to, from, n) \ - __generic_copy_to_user_nocheck((to), (from), (n)) -#define __copy_from_user_inatomic(to, from, n) \ - __generic_copy_from_user_nocheck((to), (from), (n)) - -#define __copy_to_user(to, from, n) \ -({ \ - might_fault(); \ - __copy_to_user_inatomic((to), (from), (n)); \ -}) - -#define __copy_from_user(to, from, n) \ -({ \ - might_fault(); \ - __copy_from_user_inatomic((to), (from), (n)); \ -}) #define copy_to_user(to, from, n) __generic_copy_to_user((to), (from), (n)) diff --git a/arch/mn10300/lib/usercopy.c b/arch/mn10300/lib/usercopy.c index ce8899e5e171..b48af8d4f38d 100644 --- a/arch/mn10300/lib/usercopy.c +++ b/arch/mn10300/lib/usercopy.c @@ -22,11 +22,12 @@ __generic_copy_to_user(void *to, const void *from, unsigned long n) unsigned long __generic_copy_from_user(void *to, const void *from, unsigned long n) { - if (access_ok(VERIFY_READ, from, n)) - __copy_user_zeroing(to, from, n); - else - memset(to, 0, n); - return n; + unsigned long res = n; + if (access_ok(VERIFY_READ, from, res)) + __copy_user(to, from, res); + if (unlikely(res)) + memset(to + n - res, 0, res); + return res; } /* -- cgit