xfs: updates for 4.9-rc3

Changes in this update:
o iomap page offset masking fix for page faults
o add IOMAP_REPORT to distinguish between read and fiemap map requests
o cleanups to new shared data extent code
o fix mount active status on failed log recovery
o fix broken dquots in a buffer calculation
o fix locking order issues and merge xfs_reflink_remap_range and
o rework unmapping of CoW extents and remove now unused functions
o clean state when CoW is done.
xfs: clear cowblocks tag when cow fork is emptied

The background cowblocks scan job takes care of scanning for inodes with
potentially lingering blocks in the cow fork and clearing them out. If
the background scanner reclaims the cow fork blocks, however, it doesn't
immediately clear the cowblocks tag from the inode. Instead, the inode
remains tagged until the background scanner comes around again,
discovers the inode cow fork has no blocks, clears the tag and fires the
trace_xfs_inode_free_cowblocks_invalid() tracepoint to indicate that the
inode may have been incorrectly tagged.

This is not a major functional problem as the tag is ultimately cleared.
Nonetheless, clear the tag when an inode cow fork is explicitly emptied
to avoid the extra round trip through the background scanner and
spurious "invalid" tracepoint.

Signed-off-by: Brian Foster <bfoster@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Darrick J. Wong <darrick.wong@oracle.com>
Signed-off-by: Dave Chinner <david@fromorbit.com>

1 file changed