xfs: add EOFBLOCKS inode tagging/untagging

Add the XFS_ICI_EOFBLOCKS_TAG inode tag to identify inodes with
speculatively preallocated blocks beyond EOF. An inode is tagged
when speculative preallocation occurs and untagged either via
truncate down or when post-EOF blocks are freed via release or
reclaim.

The tag management is intentionally not aggressive to prefer
simplicity over the complexity of handling all the corner cases
under which post-EOF blocks could be freed (i.e., forward
truncation, fallocate, write error conditions, etc.). This means
that a tagged inode may or may not have post-EOF blocks after a
period of time. The tag is eventually cleared when the inode is
released or reclaimed.

Signed-off-by: Brian Foster <[email protected]>
Reviewed-by: Dave Chinner <[email protected]>
Reviewed-by: Mark Tinguely <[email protected]>
Signed-off-by: Ben Myers <[email protected]>

0 files changed, 0 insertions, 0 deletions