From 57f0f512b273f60d52568b8c6b77e17f5636edc0 Mon Sep 17 00:00:00 2001 From: =?UTF-8?q?Andr=C3=A9=20Fabian=20Silva=20Delgado?= Date: Wed, 5 Aug 2015 17:04:01 -0300 Subject: Initial import --- include/uapi/linux/falloc.h | 61 +++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 61 insertions(+) create mode 100644 include/uapi/linux/falloc.h (limited to 'include/uapi/linux/falloc.h') diff --git a/include/uapi/linux/falloc.h b/include/uapi/linux/falloc.h new file mode 100644 index 000000000..3e445a760 --- /dev/null +++ b/include/uapi/linux/falloc.h @@ -0,0 +1,61 @@ +#ifndef _UAPI_FALLOC_H_ +#define _UAPI_FALLOC_H_ + +#define FALLOC_FL_KEEP_SIZE 0x01 /* default is extend size */ +#define FALLOC_FL_PUNCH_HOLE 0x02 /* de-allocates range */ +#define FALLOC_FL_NO_HIDE_STALE 0x04 /* reserved codepoint */ + +/* + * FALLOC_FL_COLLAPSE_RANGE is used to remove a range of a file + * without leaving a hole in the file. The contents of the file beyond + * the range being removed is appended to the start offset of the range + * being removed (i.e. the hole that was punched is "collapsed"), + * resulting in a file layout that looks like the range that was + * removed never existed. As such collapsing a range of a file changes + * the size of the file, reducing it by the same length of the range + * that has been removed by the operation. + * + * Different filesystems may implement different limitations on the + * granularity of the operation. Most will limit operations to + * filesystem block size boundaries, but this boundary may be larger or + * smaller depending on the filesystem and/or the configuration of the + * filesystem or file. + * + * Attempting to collapse a range that crosses the end of the file is + * considered an illegal operation - just use ftruncate(2) if you need + * to collapse a range that crosses EOF. + */ +#define FALLOC_FL_COLLAPSE_RANGE 0x08 + +/* + * FALLOC_FL_ZERO_RANGE is used to convert a range of file to zeros preferably + * without issuing data IO. Blocks should be preallocated for the regions that + * span holes in the file, and the entire range is preferable converted to + * unwritten extents - even though file system may choose to zero out the + * extent or do whatever which will result in reading zeros from the range + * while the range remains allocated for the file. + * + * This can be also used to preallocate blocks past EOF in the same way as + * with fallocate. Flag FALLOC_FL_KEEP_SIZE should cause the inode + * size to remain the same. + */ +#define FALLOC_FL_ZERO_RANGE 0x10 + +/* + * FALLOC_FL_INSERT_RANGE is use to insert space within the file size without + * overwriting any existing data. The contents of the file beyond offset are + * shifted towards right by len bytes to create a hole. As such, this + * operation will increase the size of the file by len bytes. + * + * Different filesystems may implement different limitations on the granularity + * of the operation. Most will limit operations to filesystem block size + * boundaries, but this boundary may be larger or smaller depending on + * the filesystem and/or the configuration of the filesystem or file. + * + * Attempting to insert space using this flag at OR beyond the end of + * the file is considered an illegal operation - just use ftruncate(2) or + * fallocate(2) with mode 0 for such type of operations. + */ +#define FALLOC_FL_INSERT_RANGE 0x20 + +#endif /* _UAPI_FALLOC_H_ */ -- cgit v1.2.3