xfs: prevent extsize alignment from exceeding maximum extent size

When doing delayed allocation, if the allocation size is for a
maximally sized extent, extent size alignment can push it over this
limit. This results in an assert failure in xfs_bmbt_set_allf() as
the extent length is too large to find in the extent record.

Fix this by ensuring that we allow for space that extent size
alignment requires (up to 2 * (extsize -1) blocks as we have to
handle both head and tail alignment) when limiting the maximum size
of the extent.

Signed-off-by: Dave Chinner <dchinner@redhat.com>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Alex Elder <aelder@sgi.com>
This commit is contained in:
Dave Chinner 2011-01-27 12:17:58 +11:00 committed by Alex Elder
parent 14b064ceaa
commit 4ce159890c
1 changed files with 10 additions and 0 deletions

View File

@ -4487,6 +4487,16 @@ xfs_bmapi(
/* Figure out the extent size, adjust alen */
extsz = xfs_get_extsz_hint(ip);
if (extsz) {
/*
* make sure we don't exceed a single
* extent length when we align the
* extent by reducing length we are
* going to allocate by the maximum
* amount extent size aligment may
* require.
*/
alen = XFS_FILBLKS_MIN(len,
MAXEXTLEN - (2 * extsz - 1));
error = xfs_bmap_extsize_align(mp,
&got, &prev, extsz,
rt, eof,