LXR linux/arch/sh/include/asm/uaccess.h

   1/* SPDX-License-Identifier: GPL-2.0 */
   2#ifndef __ASM_SH_UACCESS_H
   3#define __ASM_SH_UACCESS_H
   4
   5#include <asm/segment.h>
   6#include <asm/extable.h>
   7
   8#define __addr_ok(addr) \
   9        ((unsigned long __force)(addr) < current_thread_info()->addr_limit.seg)
  10
  11/*
  12 * __access_ok: Check if address with size is OK or not.
  13 *
  14 * Uhhuh, this needs 33-bit arithmetic. We have a carry..
  15 *
  16 * sum := addr + size;  carry? --> flag = true;
  17 * if (sum >= addr_limit) flag = true;
  18 */
  19#define __access_ok(addr, size) ({                              \
  20        unsigned long __ao_a = (addr), __ao_b = (size);         \
  21        unsigned long __ao_end = __ao_a + __ao_b - !!__ao_b;    \
  22        __ao_end >= __ao_a && __addr_ok(__ao_end); })
  23
  24#define access_ok(addr, size)   \
  25        (__chk_user_ptr(addr),          \
  26         __access_ok((unsigned long __force)(addr), (size)))
  27
  28#define user_addr_max() (current_thread_info()->addr_limit.seg)
  29
  30/*
  31 * Uh, these should become the main single-value transfer routines ...
  32 * They automatically use the right size if we just have the right
  33 * pointer type ...
  34 *
  35 * As SuperH uses the same address space for kernel and user data, we
  36 * can just do these as direct assignments.
  37 *
  38 * Careful to not
  39 * (a) re-use the arguments for side effects (sizeof is ok)
  40 * (b) require any knowledge of processes at this stage
  41 */
  42#define put_user(x,ptr)         __put_user_check((x), (ptr), sizeof(*(ptr)))
  43#define get_user(x,ptr)         __get_user_check((x), (ptr), sizeof(*(ptr)))
  44
  45/*
  46 * The "__xxx" versions do not do address space checking, useful when
  47 * doing multiple accesses to the same area (the user has to do the
  48 * checks by hand with "access_ok()")
  49 */
  50#define __put_user(x,ptr)       __put_user_nocheck((x), (ptr), sizeof(*(ptr)))
  51#define __get_user(x,ptr)       __get_user_nocheck((x), (ptr), sizeof(*(ptr)))
  52
  53struct __large_struct { unsigned long buf[100]; };
  54#define __m(x) (*(struct __large_struct __user *)(x))
  55
  56#define __get_user_nocheck(x,ptr,size)                          \
  57({                                                              \
  58        long __gu_err;                                          \
  59        unsigned long __gu_val;                                 \
  60        const __typeof__(*(ptr)) __user *__gu_addr = (ptr);     \
  61        __chk_user_ptr(ptr);                                    \
  62        __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
  63        (x) = (__force __typeof__(*(ptr)))__gu_val;             \
  64        __gu_err;                                               \
  65})
  66
  67#define __get_user_check(x,ptr,size)                                    \
  68({                                                                      \
  69        long __gu_err = -EFAULT;                                        \
  70        unsigned long __gu_val = 0;                                     \
  71        const __typeof__(*(ptr)) *__gu_addr = (ptr);                    \
  72        if (likely(access_ok(__gu_addr, (size))))               \
  73                __get_user_size(__gu_val, __gu_addr, (size), __gu_err); \
  74        (x) = (__force __typeof__(*(ptr)))__gu_val;                     \
  75        __gu_err;                                                       \
  76})
  77
  78#define __put_user_nocheck(x,ptr,size)                          \
  79({                                                              \
  80        long __pu_err;                                          \
  81        __typeof__(*(ptr)) __user *__pu_addr = (ptr);           \
  82        __typeof__(*(ptr)) __pu_val = x;                        \
  83        __chk_user_ptr(ptr);                                    \
  84        __put_user_size(__pu_val, __pu_addr, (size), __pu_err); \
  85        __pu_err;                                               \
  86})
  87
  88#define __put_user_check(x,ptr,size)                            \
  89({                                                              \
  90        long __pu_err = -EFAULT;                                \
  91        __typeof__(*(ptr)) __user *__pu_addr = (ptr);           \
  92        __typeof__(*(ptr)) __pu_val = x;                        \
  93        if (likely(access_ok(__pu_addr, size))) \
  94                __put_user_size(__pu_val, __pu_addr, (size),    \
  95                                __pu_err);                      \
  96        __pu_err;                                               \
  97})
  98
  99#ifdef CONFIG_SUPERH32
 100# include <asm/uaccess_32.h>
 101#else
 102# include <asm/uaccess_64.h>
 103#endif
 104
 105extern long strncpy_from_user(char *dest, const char __user *src, long count);
 106
 107extern __must_check long strnlen_user(const char __user *str, long n);
 108
 109/* Generic arbitrary sized copy.  */
 110/* Return the number of bytes NOT copied */
 111__kernel_size_t __copy_user(void *to, const void *from, __kernel_size_t n);
 112
 113static __always_inline unsigned long
 114raw_copy_from_user(void *to, const void __user *from, unsigned long n)
 115{
 116        return __copy_user(to, (__force void *)from, n);
 117}
 118
 119static __always_inline unsigned long __must_check
 120raw_copy_to_user(void __user *to, const void *from, unsigned long n)
 121{
 122        return __copy_user((__force void *)to, from, n);
 123}
 124#define INLINE_COPY_FROM_USER
 125#define INLINE_COPY_TO_USER
 126
 127/*
 128 * Clear the area and return remaining number of bytes
 129 * (on failure.  Usually it's 0.)
 130 */
 131__kernel_size_t __clear_user(void *addr, __kernel_size_t size);
 132
 133#define clear_user(addr,n)                                              \
 134({                                                                      \
 135        void __user * __cl_addr = (addr);                               \
 136        unsigned long __cl_size = (n);                                  \
 137                                                                        \
 138        if (__cl_size && access_ok(__cl_addr, __cl_size))               \
 139                __cl_size = __clear_user(__cl_addr, __cl_size);         \
 140                                                                        \
 141        __cl_size;                                                      \
 142})
 143
 144extern void *set_exception_table_vec(unsigned int vec, void *handler);
 145
 146static inline void *set_exception_table_evt(unsigned int evt, void *handler)
 147{
 148        return set_exception_table_vec(evt >> 5, handler);
 149}
 150
 151struct mem_access {
 152        unsigned long (*from)(void *dst, const void __user *src, unsigned long cnt);
 153        unsigned long (*to)(void __user *dst, const void *src, unsigned long cnt);
 154};
 155
 156int handle_unaligned_access(insn_size_t instruction, struct pt_regs *regs,
 157                            struct mem_access *ma, int, unsigned long address);
 158
 159#endif /* __ASM_SH_UACCESS_H */
 160