54 lines
1 KiB
C
54 lines
1 KiB
C
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#include <linux/uaccess.h>
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#include <linux/export.h>
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#include <linux/uio.h>
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/*
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* Copy iovec to kernel. Returns -EFAULT on error.
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*
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* Note: this modifies the original iovec.
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*/
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int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len)
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{
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while (len > 0) {
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if (iov->iov_len) {
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int copy = min_t(unsigned int, len, iov->iov_len);
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if (copy_from_user(kdata, iov->iov_base, copy))
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return -EFAULT;
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len -= copy;
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kdata += copy;
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iov->iov_base += copy;
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iov->iov_len -= copy;
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}
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iov++;
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}
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return 0;
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}
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EXPORT_SYMBOL(memcpy_fromiovec);
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/*
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* Copy kernel to iovec. Returns -EFAULT on error.
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*
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* Note: this modifies the original iovec.
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*/
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int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len)
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{
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while (len > 0) {
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if (iov->iov_len) {
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int copy = min_t(unsigned int, iov->iov_len, len);
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if (copy_to_user(iov->iov_base, kdata, copy))
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return -EFAULT;
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kdata += copy;
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len -= copy;
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iov->iov_len -= copy;
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iov->iov_base += copy;
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}
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iov++;
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}
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return 0;
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}
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EXPORT_SYMBOL(memcpy_toiovec);
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