diff options
Diffstat (limited to 'arch/frv/include/asm/uaccess.h')
| -rw-r--r-- | arch/frv/include/asm/uaccess.h | 321 |
1 files changed, 321 insertions, 0 deletions
diff --git a/arch/frv/include/asm/uaccess.h b/arch/frv/include/asm/uaccess.h new file mode 100644 index 00000000000..53650c958f4 --- /dev/null +++ b/arch/frv/include/asm/uaccess.h @@ -0,0 +1,321 @@ +/* uaccess.h: userspace accessor functions + * + * Copyright (C) 2004 Red Hat, Inc. All Rights Reserved. + * Written by David Howells (dhowells@redhat.com) + * + * This program is free software; you can redistribute it and/or + * modify it under the terms of the GNU General Public License + * as published by the Free Software Foundation; either version + * 2 of the License, or (at your option) any later version. + */ + +#ifndef _ASM_UACCESS_H +#define _ASM_UACCESS_H + +/* + * User space memory access functions + */ +#include <linux/sched.h> +#include <linux/mm.h> +#include <asm/segment.h> +#include <asm/sections.h> + +#define HAVE_ARCH_UNMAPPED_AREA /* we decide where to put mmaps */ + +#define __ptr(x) ((unsigned long __force *)(x)) + +#define VERIFY_READ 0 +#define VERIFY_WRITE 1 + +#define __addr_ok(addr) ((unsigned long)(addr) < get_addr_limit()) + +/* + * check that a range of addresses falls within the current address limit + */ +static inline int ___range_ok(unsigned long addr, unsigned long size) +{ +#ifdef CONFIG_MMU + int flag = -EFAULT, tmp; + + asm volatile ( + " addcc %3,%2,%1,icc0 \n" /* set C-flag if addr+size>4GB */ + " subcc.p %1,%4,gr0,icc1 \n" /* jump if addr+size>limit */ + " bc icc0,#0,0f \n" + " bhi icc1,#0,0f \n" + " setlos #0,%0 \n" /* mark okay */ + "0: \n" + : "=r"(flag), "=&r"(tmp) + : "r"(addr), "r"(size), "r"(get_addr_limit()), "0"(flag) + ); + + return flag; + +#else + + if (addr < memory_start || + addr > memory_end || + size > memory_end - memory_start || + addr + size > memory_end) + return -EFAULT; + + return 0; +#endif +} + +#define __range_ok(addr,size) ___range_ok((unsigned long) (addr), (unsigned long) (size)) + +#define access_ok(type,addr,size) (__range_ok((void __user *)(addr), (size)) == 0) +#define __access_ok(addr,size) (__range_ok((addr), (size)) == 0) + +/* + * The exception table consists of pairs of addresses: the first is the + * address of an instruction that is allowed to fault, and the second is + * the address at which the program should continue. No registers are + * modified, so it is entirely up to the continuation code to figure out + * what to do. + * + * All the routines below use bits of fixup code that are out of line + * with the main instruction path. This means when everything is well, + * we don't even have to jump over them. Further, they do not intrude + * on our cache or tlb entries. + */ +struct exception_table_entry +{ + unsigned long insn, fixup; +}; + +/* Returns 0 if exception not found and fixup otherwise. */ +extern unsigned long search_exception_table(unsigned long); + + +/* + * These are the main single-value transfer routines. They automatically + * use the right size if we just have the right pointer type. + */ +#define __put_user(x, ptr) \ +({ \ + int __pu_err = 0; \ + \ + typeof(*(ptr)) __pu_val = (x); \ + __chk_user_ptr(ptr); \ + \ + switch (sizeof (*(ptr))) { \ + case 1: \ + __put_user_asm(__pu_err, __pu_val, ptr, "b", "r"); \ + break; \ + case 2: \ + __put_user_asm(__pu_err, __pu_val, ptr, "h", "r"); \ + break; \ + case 4: \ + __put_user_asm(__pu_err, __pu_val, ptr, "", "r"); \ + break; \ + case 8: \ + __put_user_asm(__pu_err, __pu_val, ptr, "d", "e"); \ + break; \ + default: \ + __pu_err = __put_user_bad(); \ + break; \ + } \ + __pu_err; \ +}) + +#define put_user(x, ptr) \ +({ \ + typeof(*(ptr)) __user *_p = (ptr); \ + int _e; \ + \ + _e = __range_ok(_p, sizeof(*_p)); \ + if (_e == 0) \ + _e = __put_user((x), _p); \ + _e; \ +}) + +extern int __put_user_bad(void); + +/* + * Tell gcc we read from memory instead of writing: this is because + * we do not write to any memory gcc knows about, so there are no + * aliasing issues. + */ + +#ifdef CONFIG_MMU + +#define __put_user_asm(err,x,ptr,dsize,constraint) \ +do { \ + asm volatile("1: st"dsize"%I1 %2,%M1 \n" \ + "2: \n" \ + ".subsection 2 \n" \ + "3: setlos %3,%0 \n" \ + " bra 2b \n" \ + ".previous \n" \ + ".section __ex_table,\"a\" \n" \ + " .balign 8 \n" \ + " .long 1b,3b \n" \ + ".previous" \ + : "=r" (err) \ + : "m" (*__ptr(ptr)), constraint (x), "i"(-EFAULT), "0"(err) \ + : "memory"); \ +} while (0) + +#else + +#define __put_user_asm(err,x,ptr,bwl,con) \ +do { \ + asm(" st"bwl"%I0 %1,%M0 \n" \ + " membar \n" \ + : \ + : "m" (*__ptr(ptr)), con (x) \ + : "memory"); \ +} while (0) + +#endif + +/*****************************************************************************/ +/* + * + */ +#define __get_user(x, ptr) \ +({ \ + int __gu_err = 0; \ + __chk_user_ptr(ptr); \ + \ + switch (sizeof(*(ptr))) { \ + case 1: { \ + unsigned char __gu_val; \ + __get_user_asm(__gu_err, __gu_val, ptr, "ub", "=r"); \ + (x) = *(__force __typeof__(*(ptr)) *) &__gu_val; \ + break; \ + } \ + case 2: { \ + unsigned short __gu_val; \ + __get_user_asm(__gu_err, __gu_val, ptr, "uh", "=r"); \ + (x) = *(__force __typeof__(*(ptr)) *) &__gu_val; \ + break; \ + } \ + case 4: { \ + unsigned int __gu_val; \ + __get_user_asm(__gu_err, __gu_val, ptr, "", "=r"); \ + (x) = *(__force __typeof__(*(ptr)) *) &__gu_val; \ + break; \ + } \ + case 8: { \ + unsigned long long __gu_val; \ + __get_user_asm(__gu_err, __gu_val, ptr, "d", "=e"); \ + (x) = *(__force __typeof__(*(ptr)) *) &__gu_val; \ + break; \ + } \ + default: \ + __gu_err = __get_user_bad(); \ + break; \ + } \ + __gu_err; \ +}) + +#define get_user(x, ptr) \ +({ \ + const typeof(*(ptr)) __user *_p = (ptr);\ + int _e; \ + \ + _e = __range_ok(_p, sizeof(*_p)); \ + if (likely(_e == 0)) \ + _e = __get_user((x), _p); \ + else \ + (x) = (typeof(x)) 0; \ + _e; \ +}) + +extern int __get_user_bad(void); + +#ifdef CONFIG_MMU + +#define __get_user_asm(err,x,ptr,dtype,constraint) \ +do { \ + asm("1: ld"dtype"%I2 %M2,%1 \n" \ + "2: \n" \ + ".subsection 2 \n" \ + "3: setlos %3,%0 \n" \ + " setlos #0,%1 \n" \ + " bra 2b \n" \ + ".previous \n" \ + ".section __ex_table,\"a\" \n" \ + " .balign 8 \n" \ + " .long 1b,3b \n" \ + ".previous" \ + : "=r" (err), constraint (x) \ + : "m" (*__ptr(ptr)), "i"(-EFAULT), "0"(err) \ + ); \ +} while(0) + +#else + +#define __get_user_asm(err,x,ptr,bwl,con) \ + asm(" ld"bwl"%I1 %M1,%0 \n" \ + " membar \n" \ + : con(x) \ + : "m" (*__ptr(ptr))) + +#endif + +/*****************************************************************************/ +/* + * + */ +#define ____force(x) (__force void *)(void __user *)(x) +#ifdef CONFIG_MMU +extern long __memset_user(void *dst, unsigned long count); +extern long __memcpy_user(void *dst, const void *src, unsigned long count); + +#define clear_user(dst,count) __memset_user(____force(dst), (count)) +#define __copy_from_user_inatomic(to, from, n) __memcpy_user((to), ____force(from), (n)) +#define __copy_to_user_inatomic(to, from, n) __memcpy_user(____force(to), (from), (n)) + +#else + +#define clear_user(dst,count) (memset(____force(dst), 0, (count)), 0) +#define __copy_from_user_inatomic(to, from, n) (memcpy((to), ____force(from), (n)), 0) +#define __copy_to_user_inatomic(to, from, n) (memcpy(____force(to), (from), (n)), 0) + +#endif + +#define __clear_user clear_user + +static inline unsigned long __must_check +__copy_to_user(void __user *to, const void *from, unsigned long n) +{ + might_sleep(); + return __copy_to_user_inatomic(to, from, n); +} + +static inline unsigned long +__copy_from_user(void *to, const void __user *from, unsigned long n) +{ + might_sleep(); + return __copy_from_user_inatomic(to, from, n); +} + +static inline long copy_from_user(void *to, const void __user *from, unsigned long n) +{ + unsigned long ret = n; + + if (likely(__access_ok(from, n))) + ret = __copy_from_user(to, from, n); + + if (unlikely(ret != 0)) + memset(to + (n - ret), 0, ret); + + return ret; +} + +static inline long copy_to_user(void __user *to, const void *from, unsigned long n) +{ + return likely(__access_ok(to, n)) ? __copy_to_user(to, from, n) : n; +} + +extern long strncpy_from_user(char *dst, const char __user *src, long count); +extern long strnlen_user(const char __user *src, long count); + +#define strlen_user(str) strnlen_user(str, 32767) + +extern unsigned long search_exception_table(unsigned long addr); + +#endif /* _ASM_UACCESS_H */ |