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       1                 :            : /*
       2                 :            :  *      Berkeley style UIO structures   -       Alan Cox 1994.
       3                 :            :  *
       4                 :            :  *              This program is free software; you can redistribute it and/or
       5                 :            :  *              modify it under the terms of the GNU General Public License
       6                 :            :  *              as published by the Free Software Foundation; either version
       7                 :            :  *              2 of the License, or (at your option) any later version.
       8                 :            :  */
       9                 :            : #ifndef __LINUX_UIO_H
      10                 :            : #define __LINUX_UIO_H
      11                 :            : 
      12                 :            : #include <uapi/linux/uio.h>
      13                 :            : 
      14                 :            : 
      15                 :            : struct kvec {
      16                 :            :         void *iov_base; /* and that should *never* hold a userland pointer */
      17                 :            :         size_t iov_len;
      18                 :            : };
      19                 :            : 
      20                 :            : /*
      21                 :            :  * Total number of bytes covered by an iovec.
      22                 :            :  *
      23                 :            :  * NOTE that it is not safe to use this function until all the iovec's
      24                 :            :  * segment lengths have been validated.  Because the individual lengths can
      25                 :            :  * overflow a size_t when added together.
      26                 :            :  */
      27                 :            : static inline size_t iov_length(const struct iovec *iov, unsigned long nr_segs)
      28                 :            : {
      29                 :            :         unsigned long seg;
      30                 :            :         size_t ret = 0;
      31                 :            : 
      32 [ +  + ][ +  + ]:    5616073 :         for (seg = 0; seg < nr_segs; seg++)
         [ +  + ][ #  # ]
                 [ #  # ]
      33                 :    3385806 :                 ret += iov[seg].iov_len;
      34                 :            :         return ret;
      35                 :            : }
      36                 :            : 
      37                 :            : unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to);
      38                 :            : 
      39                 :            : int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len);
      40                 :            : int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len);
      41                 :            : #endif