Root/lib/iovec.c

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
11int 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}
28EXPORT_SYMBOL(memcpy_fromiovec);
29
30/*
31 * Copy kernel to iovec. Returns -EFAULT on error.
32 *
33 * Note: this modifies the original iovec.
34 */
35
36int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len)
37{
38    while (len > 0) {
39        if (iov->iov_len) {
40            int copy = min_t(unsigned int, iov->iov_len, len);
41            if (copy_to_user(iov->iov_base, kdata, copy))
42                return -EFAULT;
43            kdata += copy;
44            len -= copy;
45            iov->iov_len -= copy;
46            iov->iov_base += copy;
47        }
48        iov++;
49    }
50
51    return 0;
52}
53EXPORT_SYMBOL(memcpy_toiovec);
54

Archive Download this file



interactive