diff options
Diffstat (limited to 'arch/c6x/include/asm/uaccess.h')
-rw-r--r-- | arch/c6x/include/asm/uaccess.h | 107 |
1 files changed, 107 insertions, 0 deletions
diff --git a/arch/c6x/include/asm/uaccess.h b/arch/c6x/include/asm/uaccess.h new file mode 100644 index 00000000000..453dd263bee --- /dev/null +++ b/arch/c6x/include/asm/uaccess.h @@ -0,0 +1,107 @@ +/* + * Copyright (C) 2011 Texas Instruments Incorporated + * Author: Mark Salter <msalter@redhat.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2 as + * published by the Free Software Foundation. + */ +#ifndef _ASM_C6X_UACCESS_H +#define _ASM_C6X_UACCESS_H + +#include <linux/types.h> +#include <linux/compiler.h> +#include <linux/string.h> + +#ifdef CONFIG_ACCESS_CHECK +#define __access_ok _access_ok +#endif + +/* + * __copy_from_user/copy_to_user are based on ones in asm-generic/uaccess.h + * + * C6X supports unaligned 32 and 64 bit loads and stores. + */ +static inline __must_check long __copy_from_user(void *to, + const void __user *from, unsigned long n) +{ + u32 tmp32; + u64 tmp64; + + if (__builtin_constant_p(n)) { + switch (n) { + case 1: + *(u8 *)to = *(u8 __force *)from; + return 0; + case 4: + asm volatile ("ldnw .d1t1 *%2,%0\n" + "nop 4\n" + "stnw .d1t1 %0,*%1\n" + : "=&a"(tmp32) + : "A"(to), "a"(from) + : "memory"); + return 0; + case 8: + asm volatile ("ldndw .d1t1 *%2,%0\n" + "nop 4\n" + "stndw .d1t1 %0,*%1\n" + : "=&a"(tmp64) + : "a"(to), "a"(from) + : "memory"); + return 0; + default: + break; + } + } + + memcpy(to, (const void __force *)from, n); + return 0; +} + +static inline __must_check long __copy_to_user(void __user *to, + const void *from, unsigned long n) +{ + u32 tmp32; + u64 tmp64; + + if (__builtin_constant_p(n)) { + switch (n) { + case 1: + *(u8 __force *)to = *(u8 *)from; + return 0; + case 4: + asm volatile ("ldnw .d1t1 *%2,%0\n" + "nop 4\n" + "stnw .d1t1 %0,*%1\n" + : "=&a"(tmp32) + : "a"(to), "a"(from) + : "memory"); + return 0; + case 8: + asm volatile ("ldndw .d1t1 *%2,%0\n" + "nop 4\n" + "stndw .d1t1 %0,*%1\n" + : "=&a"(tmp64) + : "a"(to), "a"(from) + : "memory"); + return 0; + default: + break; + } + } + + memcpy((void __force *)to, from, n); + return 0; +} + +#define __copy_to_user __copy_to_user +#define __copy_from_user __copy_from_user + +extern int _access_ok(unsigned long addr, unsigned long size); +#ifdef CONFIG_ACCESS_CHECK +#define __access_ok _access_ok +#endif + +#include <asm-generic/uaccess.h> + +#endif /* _ASM_C6X_UACCESS_H */ |