projects / linux.git / blame
| Commit | Line | Data |
|---|---|---|
| 1da177e4 LT |
1 | #ifndef __LINUX_UIO_H |
| 2 | #define __LINUX_UIO_H | |
| 3 | ||
| 4 | #include <linux/compiler.h> | |
| 5 | #include <linux/types.h> | |
| 6 | ||
| 7 | /* | |
| 8 | * Berkeley style UIO structures - Alan Cox 1994. | |
| 9 | * | |
| 10 | * This program is free software; you can redistribute it and/or | |
| 11 | * modify it under the terms of the GNU General Public License | |
| 12 | * as published by the Free Software Foundation; either version | |
| 13 | * 2 of the License, or (at your option) any later version. | |
| 14 | */ | |
| 15 | ||
| 1da177e4 LT |
16 | struct iovec |
| 17 | { | |
| 18 | void __user *iov_base; /* BSD uses caddr_t (1003.1g requires void *) */ | |
| 19 | __kernel_size_t iov_len; /* Must be size_t (1003.1g) */ | |
| 20 | }; | |
| 21 | ||
| 1da177e4 LT |
22 | /* |
| 23 | * UIO_MAXIOV shall be at least 16 1003.1g (5.4.1.1) | |
| 24 | */ | |
| 25 | ||
| 26 | #define UIO_FASTIOV 8 | |
| 27 | #define UIO_MAXIOV 1024 | |
| 1da177e4 | 28 | |
| 812ed032 JS |
29 | #ifdef __KERNEL__ |
| 30 | ||
| 31 | struct kvec { | |
| 32 | void *iov_base; /* and that should *never* hold a userland pointer */ | |
| 33 | size_t iov_len; | |
| 34 | }; | |
| 35 | ||
| 1da177e4 LT |
36 | /* |
| 37 | * Total number of bytes covered by an iovec. | |
| 38 | * | |
| 39 | * NOTE that it is not safe to use this function until all the iovec's | |
| 40 | * segment lengths have been validated. Because the individual lengths can | |
| 41 | * overflow a size_t when added together. | |
| 42 | */ | |
| 43 | static inline size_t iov_length(const struct iovec *iov, unsigned long nr_segs) | |
| 44 | { | |
| 45 | unsigned long seg; | |
| 46 | size_t ret = 0; | |
| 47 | ||
| 48 | for (seg = 0; seg < nr_segs; seg++) | |
| 49 | ret += iov[seg].iov_len; | |
| 50 | return ret; | |
| 51 | } | |
| 52 | ||
| 53 | unsigned long iov_shorten(struct iovec *iov, unsigned long nr_segs, size_t to); | |
| 812ed032 | 54 | #endif |
| 1da177e4 LT |
55 | |
| 56 | #endif |