diff options
| author | Meizu OpenSource <patchwork@meizu.com> | 2016-08-15 10:19:42 +0800 |
|---|---|---|
| committer | Meizu OpenSource <patchwork@meizu.com> | 2016-08-15 10:19:42 +0800 |
| commit | d2e1446d81725c351dc73a03b397ce043fb18452 (patch) | |
| tree | 4dbc616b7f92aea39cd697a9084205ddb805e344 /include/linux/uio.h | |
first commit
Diffstat (limited to 'include/linux/uio.h')
| -rw-r--r-- | include/linux/uio.h | 41 |
1 files changed, 41 insertions, 0 deletions
diff --git a/include/linux/uio.h b/include/linux/uio.h new file mode 100644 index 000000000..c55ce243c --- /dev/null +++ b/include/linux/uio.h @@ -0,0 +1,41 @@ +/* + * 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. + */ +#ifndef __LINUX_UIO_H +#define __LINUX_UIO_H + +#include <uapi/linux/uio.h> + + +struct kvec { + void *iov_base; /* and that should *never* hold a userland pointer */ + size_t iov_len; +}; + +/* + * 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); + +int memcpy_fromiovec(unsigned char *kdata, struct iovec *iov, int len); +int memcpy_toiovec(struct iovec *iov, unsigned char *kdata, int len); +#endif |
