Commit | Line | Data |
---|---|---|
d2f83e90 RR |
1 | #include <linux/uaccess.h> |
2 | #include <linux/export.h> | |
3 | #include <linux/uio.h> | |
4 | ||
5 | /* | |
6 | * Copy iovec to kernel. Returns -EFAULT on error. | |
7 | * | |
8 | * Note: this modifies the original iovec. | |
9 | */ | |
10 | ||
11 | int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len) | |
12 | { | |
13 | while (len > 0) { | |
14 | if (iov->iov_len) { | |
15 | int copy = min_t(unsigned int, len, iov->iov_len); | |
16 | if (copy_from_user(kdata, iov->iov_base, copy)) | |
17 | return -EFAULT; | |
18 | len -= copy; | |
19 | kdata += copy; | |
20 | iov->iov_base += copy; | |
21 | iov->iov_len -= copy; | |
22 | } | |
23 | iov++; | |
24 | } | |
25 | ||
26 | return 0; | |
27 | } | |
28 | EXPORT_SYMBOL(memcpy_fromiovec); | |
29 | ||
ac5ccdba MT |
30 | /* |
31 | * Copy kernel to iovec. Returns -EFAULT on error. | |
32 | */ | |
33 | ||
34 | int memcpy_toiovecend(const struct iovec *iov, unsigned char *kdata, | |
35 | int offset, int len) | |
36 | { | |
37 | int copy; | |
38 | for (; len > 0; ++iov) { | |
39 | /* Skip over the finished iovecs */ | |
40 | if (unlikely(offset >= iov->iov_len)) { | |
41 | offset -= iov->iov_len; | |
42 | continue; | |
43 | } | |
44 | copy = min_t(unsigned int, iov->iov_len - offset, len); | |
45 | if (copy_to_user(iov->iov_base + offset, kdata, copy)) | |
46 | return -EFAULT; | |
47 | offset = 0; | |
48 | kdata += copy; | |
49 | len -= copy; | |
50 | } | |
51 | ||
52 | return 0; | |
53 | } | |
54 | EXPORT_SYMBOL(memcpy_toiovecend); | |
55 | ||
56 | /* | |
57 | * Copy iovec to kernel. Returns -EFAULT on error. | |
58 | */ | |
59 | ||
60 | int memcpy_fromiovecend(unsigned char *kdata, const struct iovec *iov, | |
61 | int offset, int len) | |
62 | { | |
06ebb06d SL |
63 | /* No data? Done! */ |
64 | if (len == 0) | |
65 | return 0; | |
66 | ||
ac5ccdba MT |
67 | /* Skip over the finished iovecs */ |
68 | while (offset >= iov->iov_len) { | |
69 | offset -= iov->iov_len; | |
70 | iov++; | |
71 | } | |
72 | ||
73 | while (len > 0) { | |
74 | u8 __user *base = iov->iov_base + offset; | |
75 | int copy = min_t(unsigned int, len, iov->iov_len - offset); | |
76 | ||
77 | offset = 0; | |
78 | if (copy_from_user(kdata, base, copy)) | |
79 | return -EFAULT; | |
80 | len -= copy; | |
81 | kdata += copy; | |
82 | iov++; | |
83 | } | |
84 | ||
85 | return 0; | |
86 | } | |
87 | EXPORT_SYMBOL(memcpy_fromiovecend); |