LXR linux/sound/core/memory.c

   1/*
   2 *  Copyright (c) by Jaroslav Kysela <perex@perex.cz>
   3 * 
   4 *  Misc memory accessors
   5 *
   6 *
   7 *   This program is free software; you can redistribute it and/or modify
   8 *   it under the terms of the GNU General Public License as published by
   9 *   the Free Software Foundation; either version 2 of the License, or
  10 *   (at your option) any later version.
  11 *
  12 *   This program is distributed in the hope that it will be useful,
  13 *   but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 *   GNU General Public License for more details.
  16 *
  17 *   You should have received a copy of the GNU General Public License
  18 *   along with this program; if not, write to the Free Software
  19 *   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307 USA
  20 *
  21 */
  22
  23#include <asm/io.h>
  24#include <asm/uaccess.h>
  25#include <sound/core.h>
  26
  27/**
  28 * copy_to_user_fromio - copy data from mmio-space to user-space
  29 * @dst: the destination pointer on user-space
  30 * @src: the source pointer on mmio
  31 * @count: the data size to copy in bytes
  32 *
  33 * Copies the data from mmio-space to user-space.
  34 *
  35 * Returns zero if successful, or non-zero on failure.
  36 */
  37int copy_to_user_fromio(void __user *dst, const volatile void __iomem *src, size_t count)
  38{
  39#if defined(__i386__) || defined(CONFIG_SPARC32)
  40        return copy_to_user(dst, (const void __force*)src, count) ? -EFAULT : 0;
  41#else
  42        char buf[256];
  43        while (count) {
  44                size_t c = count;
  45                if (c > sizeof(buf))
  46                        c = sizeof(buf);
  47                memcpy_fromio(buf, (void __iomem *)src, c);
  48                if (copy_to_user(dst, buf, c))
  49                        return -EFAULT;
  50                count -= c;
  51                dst += c;
  52                src += c;
  53        }
  54        return 0;
  55#endif
  56}
  57
  58EXPORT_SYMBOL(copy_to_user_fromio);
  59
  60/**
  61 * copy_from_user_toio - copy data from user-space to mmio-space
  62 * @dst: the destination pointer on mmio-space
  63 * @src: the source pointer on user-space
  64 * @count: the data size to copy in bytes
  65 *
  66 * Copies the data from user-space to mmio-space.
  67 *
  68 * Returns zero if successful, or non-zero on failure.
  69 */
  70int copy_from_user_toio(volatile void __iomem *dst, const void __user *src, size_t count)
  71{
  72#if defined(__i386__) || defined(CONFIG_SPARC32)
  73        return copy_from_user((void __force *)dst, src, count) ? -EFAULT : 0;
  74#else
  75        char buf[256];
  76        while (count) {
  77                size_t c = count;
  78                if (c > sizeof(buf))
  79                        c = sizeof(buf);
  80                if (copy_from_user(buf, src, c))
  81                        return -EFAULT;
  82                memcpy_toio(dst, buf, c);
  83                count -= c;
  84                dst += c;
  85                src += c;
  86        }
  87        return 0;
  88#endif
  89}
  90
  91EXPORT_SYMBOL(copy_from_user_toio);
  92