[PATCH 0/2] xfs: fix up xfs_swap_extent_forks inline extent handling

From: Eric Sandeen <sandeen@redhat.com>
To: linux-xfs <linux-xfs@vger.kernel.org>
Subject: [PATCH 0/2] xfs: fix up xfs_swap_extent_forks inline extent handling
Date: Fri, 4 Nov 2016 21:09:25 -0500	[thread overview]
Message-ID: <d279d52e-49f6-6fc2-c78b-0054d7ee0a1e@redhat.com> (raw)

xfs_swap_extent_forks() was wrongly using di_nextents
(on-disk extents) for determining whether the /incore/
inode could keep extents inline.  The code should be testing
if_bytes, not di_nextents, to make this determination.

The mistake led to an oops in some situations when running
xfs_fsr.

Throughout the code we have this sort of open-coded handling
like:

nextents = ip->i_df.if_bytes / (uint)sizeof(xfs_bmbt_rec_t);

so patch 2 creates a helper for that and uses it throughout
the codebase.

I should maybe also create a helper for the things that expand
it back out, i.e. nextents * (uint)sizeof(xfs_bmbt_rec_t) but
that seems error prone...

-Eric