#ifndef __LINUX_UIO_H #define __LINUX_UIO_H #include <linux/compiler.h> #include <linux/types.h> /* * Berkeley style UIO structures - Alan Cox 1994. * * This program is free software; you can redistribute it and/or * modify it under the terms of the GNU General Public License * as published by the Free Software Foundation; either version * 2 of the License, or (at your option) any later version. */ struct iovec { void __user *iov_base; /* BSD uses caddr_t (1003.1g requires void *) */ __kernel_size_t iov_len; /* Must be size_t (1003.1g) */ }; #ifdef __KERNEL__ struct kvec { void *iov_base; /* and that should *never* hold a userland pointer */ size_t iov_len; }; #endif /* * UIO_MAXIOV shall be at least 16 1003.1g (5.4.1.1) */ #define UIO_FASTIOV 8 #define UIO_MAXIOV 1024 /* * Total number of bytes covered by an iovec. * * NOTE that it is not safe to use this function until all the iovec's * segment lengths have been validated. Because the individual lengths can * overflow a size_t when added together. */ static inline size_t iov_length(const struct iovec *iov, unsigned long nr_segs) { unsigned long seg; size_t ret = 0; for (seg = 0; seg < nr_segs; seg++) ret += iov[seg].iov_len; return ret; } unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to); #endif