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authorLinus Torvalds <torvalds@linux-foundation.org>2014-04-04 15:50:08 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2014-04-04 15:50:08 -0700
commitd15e03104eb9a4f8e244ab6ed3ca5a107e46db13 (patch)
tree31971cfaa50ea4da3f887f2eb33cb513d09b32bc /include/uapi
parent24e7ea3bea94fe05eae5019f5f12bcdc98fc5157 (diff)
parenta6cf33bc566c5fe888bfa9cf6448037c90661f67 (diff)
Merge tag 'xfs-for-linus-3.15-rc1' of git://oss.sgi.com/xfs/xfs
Pull xfs update from Dave Chinner: "There are a couple of new fallocate features in this request - it was decided that it was easiest to push them through the XFS tree using topic branches and have the ext4 support be based on those branches. Hence you may see some overlap with the ext4 tree merge depending on how they including those topic branches into their tree. Other than that, there is O_TMPFILE support, some cleanups and bug fixes. The main changes in the XFS tree for 3.15-rc1 are: - O_TMPFILE support - allowing AIO+DIO writes beyond EOF - FALLOC_FL_COLLAPSE_RANGE support for fallocate syscall and XFS implementation - FALLOC_FL_ZERO_RANGE support for fallocate syscall and XFS implementation - IO verifier cleanup and rework - stack usage reduction changes - vm_map_ram NOIO context fixes to remove lockdep warings - various bug fixes and cleanups" * tag 'xfs-for-linus-3.15-rc1' of git://oss.sgi.com/xfs/xfs: (34 commits) xfs: fix directory hash ordering bug xfs: extra semi-colon breaks a condition xfs: Add support for FALLOC_FL_ZERO_RANGE fs: Introduce FALLOC_FL_ZERO_RANGE flag for fallocate xfs: inode log reservations are still too small xfs: xfs_check_page_type buffer checks need help xfs: avoid AGI/AGF deadlock scenario for inode chunk allocation xfs: use NOIO contexts for vm_map_ram xfs: don't leak EFSBADCRC to userspace xfs: fix directory inode iolock lockdep false positive xfs: allocate xfs_da_args to reduce stack footprint xfs: always do log forces via the workqueue xfs: modify verifiers to differentiate CRC from other errors xfs: print useful caller information in xfs_error_report xfs: add xfs_verifier_error() xfs: add helper for updating checksums on xfs_bufs xfs: add helper for verifying checksums on xfs_bufs xfs: Use defines for CRC offsets in all cases xfs: skip pointless CRC updates after verifier failures xfs: Add support FALLOC_FL_COLLAPSE_RANGE for fallocate ...
Diffstat (limited to 'include/uapi')
-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_ */