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1// SPDX-License-Identifier: GPL-2.0-or-later2/*3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>4 * 5 * Misc memory accessors6 */7 8#include <linux/export.h>9#include <linux/io.h>10#include <linux/uaccess.h>11#include <sound/core.h>12#include <sound/pcm.h>13 14/**15 * copy_to_user_fromio - copy data from mmio-space to user-space16 * @dst: the destination pointer on user-space17 * @src: the source pointer on mmio18 * @count: the data size to copy in bytes19 *20 * Copies the data from mmio-space to user-space.21 *22 * Return: Zero if successful, or non-zero on failure.23 */24int copy_to_user_fromio(void __user *dst, const volatile void __iomem *src, size_t count)25{26 struct iov_iter iter;27 28 if (import_ubuf(ITER_DEST, dst, count, &iter))29 return -EFAULT;30 return copy_to_iter_fromio(&iter, (const void __iomem *)src, count);31}32EXPORT_SYMBOL(copy_to_user_fromio);33 34/**35 * copy_to_iter_fromio - copy data from mmio-space to iov_iter36 * @dst: the destination iov_iter37 * @src: the source pointer on mmio38 * @count: the data size to copy in bytes39 *40 * Copies the data from mmio-space to iov_iter.41 *42 * Return: Zero if successful, or non-zero on failure.43 */44int copy_to_iter_fromio(struct iov_iter *dst, const void __iomem *src,45 size_t count)46{47#if defined(__i386__) || defined(CONFIG_SPARC32)48 return copy_to_iter((const void __force *)src, count, dst) == count ? 0 : -EFAULT;49#else50 char buf[256];51 while (count) {52 size_t c = count;53 if (c > sizeof(buf))54 c = sizeof(buf);55 memcpy_fromio(buf, (void __iomem *)src, c);56 if (copy_to_iter(buf, c, dst) != c)57 return -EFAULT;58 count -= c;59 src += c;60 }61 return 0;62#endif63}64EXPORT_SYMBOL(copy_to_iter_fromio);65 66/**67 * copy_from_user_toio - copy data from user-space to mmio-space68 * @dst: the destination pointer on mmio-space69 * @src: the source pointer on user-space70 * @count: the data size to copy in bytes71 *72 * Copies the data from user-space to mmio-space.73 *74 * Return: Zero if successful, or non-zero on failure.75 */76int copy_from_user_toio(volatile void __iomem *dst, const void __user *src, size_t count)77{78 struct iov_iter iter;79 80 if (import_ubuf(ITER_SOURCE, (void __user *)src, count, &iter))81 return -EFAULT;82 return copy_from_iter_toio((void __iomem *)dst, &iter, count);83}84EXPORT_SYMBOL(copy_from_user_toio);85 86/**87 * copy_from_iter_toio - copy data from iov_iter to mmio-space88 * @dst: the destination pointer on mmio-space89 * @src: the source iov_iter90 * @count: the data size to copy in bytes91 *92 * Copies the data from iov_iter to mmio-space.93 *94 * Return: Zero if successful, or non-zero on failure.95 */96int copy_from_iter_toio(void __iomem *dst, struct iov_iter *src, size_t count)97{98#if defined(__i386__) || defined(CONFIG_SPARC32)99 return copy_from_iter((void __force *)dst, count, src) == count ? 0 : -EFAULT;100#else101 char buf[256];102 while (count) {103 size_t c = count;104 if (c > sizeof(buf))105 c = sizeof(buf);106 if (copy_from_iter(buf, c, src) != c)107 return -EFAULT;108 memcpy_toio(dst, buf, c);109 count -= c;110 dst += c;111 }112 return 0;113#endif114}115EXPORT_SYMBOL(copy_from_iter_toio);116