[Cluster-devel] [GFS2 PATCH v3 0/3] Fix erroneous ETXTBSY problems with GFS2

[Bob Peterson]

Hi,

On 03 November, I posted an earlier "v2" version of this 3-patch set.
Since then, I've uncovered some problems in testing and re-reviewing.
This is a revised version of the three patches that fixes those problems.
Since the v2 patches had already been pushed to the for-next branch of
the linux-gfs2 git tree, I pushed these revised versions before sending
them out for review to "stop the bleeding".

Bob peterson
---
Commit 2b3dcf3 (GFS2: Increase i_writecount during gfs2_setattr_size)
added a bunch of calls to get_write_access() in order to ensure file close
could not delete an inode's multi-block reservation while the function
was running. For example, close was interfering with setattr_size.
The patch worked as expected, but there was an unintended consequence:
If a GFS2 file is open, you can't do these functions (like chown) or
you'll get ETXTBSY (Text file busy). For example, if you're running a
program and try to do chown or chattr while it's running, it will fail.

This problem is easily fixed by reverting that patch and including the
multi-block reservation structure inside the gfs2 inode. The problem is,
the gfs2 inode then grows to a much bigger size.

This patch set takes some measures to reduce the size of the gfs2 inode
and then making the reservations part of the inode.

Before the patch set, GFS2 inodes were 864 bytes in length. Adding just
the reservations structure bumped it up to 1280, which is not good.
With all these patches in place, the size is 968, which is comparable
to ext4 (1032) and xfs (1088). Further savings are possible (and I've
prototyped a few) but I don't want to get too extreme here.

Bob Peterson (3):
  GFS2: Extract quota data from reservations structure (revert 5407e24)
  GFS2: Make rgrp reservations part of the gfs2_inode structure
  GFS2: Reduce size of incore inode

 fs/gfs2/aops.c   |   2 +-
 fs/gfs2/bmap.c   |  13 ++-----
 fs/gfs2/file.c   |  25 +++++-------
 fs/gfs2/glock.c  |  10 ++---
 fs/gfs2/glock.h  |  26 ++++++-------
 fs/gfs2/incore.h |  19 ++++++----
 fs/gfs2/inode.c  |  23 +++++------
 fs/gfs2/main.c   |  16 ++++----
 fs/gfs2/quota.c  | 113 +++++++++++++++++++++++++++++++++++--------------------
 fs/gfs2/quota.h  |   2 +
 fs/gfs2/rgrp.c   |  60 +++++------------------------
 fs/gfs2/rgrp.h   |   4 +-
 fs/gfs2/super.c  |   9 +++--
 fs/gfs2/util.c   |   2 +-
 fs/gfs2/util.h   |   2 +-
 15 files changed, 154 insertions(+), 172 deletions(-)

-- 
2.5.0