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authorEmmanuel Grumbach <emmanuel.grumbach@intel.com>2014-05-06 20:37:42 +0300
committerEmmanuel Grumbach <emmanuel.grumbach@intel.com>2014-05-06 20:37:42 +0300
commitcebeb0f1885fa93c44be5d4e0b9b640210ff088c (patch)
treea33e4af4ddaa7a57f997ab9a2baceb48209670cd /include/uapi/linux/falloc.h
parentMerge remote-tracking branch 'iwlwifi-fixes/master' into iwlwifi-next (diff)
parentrsi: Changing opcode for sta mode according to changes in firmware (diff)
Merge remote-tracking branch 'wireless-next/master' into iwlwifi-next
Diffstat (limited to 'include/uapi/linux/falloc.h')
-rw-r--r--include/uapi/linux/falloc.h35
1 files changed, 35 insertions, 0 deletions
diff --git a/include/uapi/linux/falloc.h b/include/uapi/linux/falloc.h
index 990c4ccf8b61..d1197ae3723c 100644
--- a/include/uapi/linux/falloc.h
+++ b/include/uapi/linux/falloc.h
@@ -5,5 +5,40 @@
#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
#endif /* _UAPI_FALLOC_H_ */