LXR linux/arch/c6x/include/asm/uaccess.h

   1/* SPDX-License-Identifier: GPL-2.0-only */
   2/*
   3 *  Copyright (C) 2011 Texas Instruments Incorporated
   4 *  Author: Mark Salter <msalter@redhat.com>
   5 */
   6#ifndef _ASM_C6X_UACCESS_H
   7#define _ASM_C6X_UACCESS_H
   8
   9#include <linux/types.h>
  10#include <linux/compiler.h>
  11#include <linux/string.h>
  12
  13/*
  14 * C6X supports unaligned 32 and 64 bit loads and stores.
  15 */
  16static inline __must_check unsigned long
  17raw_copy_from_user(void *to, const void __user *from, unsigned long n)
  18{
  19        u32 tmp32;
  20        u64 tmp64;
  21
  22        if (__builtin_constant_p(n)) {
  23                switch (n) {
  24                case 1:
  25                        *(u8 *)to = *(u8 __force *)from;
  26                        return 0;
  27                case 4:
  28                        asm volatile ("ldnw .d1t1 *%2,%0\n"
  29                                      "nop  4\n"
  30                                      "stnw .d1t1 %0,*%1\n"
  31                                      : "=&a"(tmp32)
  32                                      : "A"(to), "a"(from)
  33                                      : "memory");
  34                        return 0;
  35                case 8:
  36                        asm volatile ("ldndw .d1t1 *%2,%0\n"
  37                                      "nop   4\n"
  38                                      "stndw .d1t1 %0,*%1\n"
  39                                      : "=&a"(tmp64)
  40                                      : "a"(to), "a"(from)
  41                                      : "memory");
  42                        return 0;
  43                default:
  44                        break;
  45                }
  46        }
  47
  48        memcpy(to, (const void __force *)from, n);
  49        return 0;
  50}
  51
  52static inline __must_check unsigned long
  53raw_copy_to_user(void __user *to, const void *from, unsigned long n)
  54{
  55        u32 tmp32;
  56        u64 tmp64;
  57
  58        if (__builtin_constant_p(n)) {
  59                switch (n) {
  60                case 1:
  61                        *(u8 __force *)to = *(u8 *)from;
  62                        return 0;
  63                case 4:
  64                        asm volatile ("ldnw .d1t1 *%2,%0\n"
  65                                      "nop  4\n"
  66                                      "stnw .d1t1 %0,*%1\n"
  67                                      : "=&a"(tmp32)
  68                                      : "a"(to), "a"(from)
  69                                      : "memory");
  70                        return 0;
  71                case 8:
  72                        asm volatile ("ldndw .d1t1 *%2,%0\n"
  73                                      "nop   4\n"
  74                                      "stndw .d1t1 %0,*%1\n"
  75                                      : "=&a"(tmp64)
  76                                      : "a"(to), "a"(from)
  77                                      : "memory");
  78                        return 0;
  79                default:
  80                        break;
  81                }
  82        }
  83
  84        memcpy((void __force *)to, from, n);
  85        return 0;
  86}
  87#define INLINE_COPY_FROM_USER
  88#define INLINE_COPY_TO_USER
  89
  90extern int _access_ok(unsigned long addr, unsigned long size);
  91#ifdef CONFIG_ACCESS_CHECK
  92#define __access_ok _access_ok
  93#endif
  94
  95#include <asm-generic/uaccess.h>
  96
  97#endif /* _ASM_C6X_UACCESS_H */
  98