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#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.
* 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.
#endif /* _UAPI_FALLOC_H_ */