1// SPDX-License-Identifier: GPL-2.0-or-later
2/*
3 * Copyright (c) by Jaroslav Kysela <perex@perex.cz>
4 *
5 * Misc memory accessors
6 */
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-space
16 * @dst: the destination pointer on user-space
17 * @src: the source pointer on mmio
18 * @count: the data size to copy in bytes
19 *
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, buf: dst, len: count, i: &iter))
29 return -EFAULT;
30 if (copy_to_iter_fromio(src: (const void __iomem *)src, bytes: count, iter: &iter) != count)
31 return -EFAULT;
32 return 0;
33}
34EXPORT_SYMBOL(copy_to_user_fromio);
35
36/**
37 * copy_to_iter_fromio - copy data from mmio-space to iov_iter
38 * @src: the source pointer on mmio
39 * @count: the data size to copy in bytes
40 * @dst: the destination iov_iter
41 *
42 * Copies the data from mmio-space to iov_iter.
43 *
44 * Return: number of bytes to be copied
45 */
46size_t copy_to_iter_fromio(const void __iomem *src, size_t count,
47 struct iov_iter *dst)
48{
49#if defined(__i386__) || defined(CONFIG_SPARC32)
50 return copy_to_iter((const void __force *)src, count, dst);
51#else
52 char buf[256];
53 size_t res = 0;
54
55 while (count) {
56 size_t c = count;
57 if (c > sizeof(buf))
58 c = sizeof(buf);
59 memcpy_fromio(buf, (void __iomem *)src, c);
60 if (copy_to_iter(addr: buf, bytes: c, i: dst) != c)
61 return res;
62 count -= c;
63 src += c;
64 res += c;
65 }
66 return res;
67#endif
68}
69EXPORT_SYMBOL(copy_to_iter_fromio);
70
71/**
72 * copy_from_user_toio - copy data from user-space to mmio-space
73 * @dst: the destination pointer on mmio-space
74 * @src: the source pointer on user-space
75 * @count: the data size to copy in bytes
76 *
77 * Copies the data from user-space to mmio-space.
78 *
79 * Return: Zero if successful, or non-zero on failure.
80 */
81int copy_from_user_toio(volatile void __iomem *dst, const void __user *src, size_t count)
82{
83 struct iov_iter iter;
84
85 if (import_ubuf(ITER_SOURCE, buf: (void __user *)src, len: count, i: &iter))
86 return -EFAULT;
87 if (copy_from_iter_toio(dst: (void __iomem *)dst, bytes: count, iter: &iter) != count)
88 return -EFAULT;
89 return 0;
90}
91EXPORT_SYMBOL(copy_from_user_toio);
92
93/**
94 * copy_from_iter_toio - copy data from iov_iter to mmio-space
95 * @dst: the destination pointer on mmio-space
96 * @count: the data size to copy in bytes
97 * @src: the source iov_iter
98 *
99 * Copies the data from iov_iter to mmio-space.
100 *
101 * Return: number of bytes to be copied
102 */
103size_t copy_from_iter_toio(void __iomem *dst, size_t count,
104 struct iov_iter *src)
105{
106#if defined(__i386__) || defined(CONFIG_SPARC32)
107 return copy_from_iter((void __force *)dst, count, src);
108#else
109 char buf[256];
110 size_t res = 0;
111
112 while (count) {
113 size_t c = count;
114 if (c > sizeof(buf))
115 c = sizeof(buf);
116 if (copy_from_iter(addr: buf, bytes: c, i: src) != c)
117 return res;
118 memcpy_toio(dst, buf, c);
119 count -= c;
120 dst += c;
121 res += c;
122 }
123 return res;
124#endif
125}
126EXPORT_SYMBOL(copy_from_iter_toio);
127