xfs: fix rounding in xfs_free_file_space
authorDave Chinner <dchinner@redhat.com>
Sun, 19 May 2013 23:51:09 +0000 (09:51 +1000)
committerBen Myers <bpm@sgi.com>
Fri, 24 May 2013 21:27:41 +0000 (16:27 -0500)
commit7031d0e1c46e2b1c869458233dd216cb72af41b2
treeea6b8690937f4a2129eafc176ee8adcaeb8f5293
parent480d7467e4aaa3dc38088baf56bc3eb3599f5d26
xfs: fix rounding in xfs_free_file_space

The offset passed into xfs_free_file_space() needs to be rounded
down to a certain size, but the rounding mask is built by a 32 bit
variable. Hence the mask will always mask off the upper 32 bits of
the offset and lead to incorrect writeback and invalidation ranges.

This is not actually exposed as a bug because we writeback and
invalidate from the rounded offset to the end of the file, and hence
the offset we are actually punching a hole out of will always be
covered by the code. This needs fixing, however, if we ever want to
use exact ranges for writeback/invalidation here...

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Brian Foster <bfoster@redhat.com>
Signed-off-by: Ben Myers <bpm@sgi.com>
(cherry picked from commit 28ca489c63e9aceed8801d2f82d731b3c9aa50f5)
fs/xfs/xfs_vnodeops.c