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  1. 04 Feb, 2009 7 commits
  3. 03 Feb, 2009 29 commits
  5. 02 Feb, 2009 4 commits
    • Mark Fasheh's avatar
      ocfs2: add quota call to ocfs2_remove_btree_range() · fd4ef231
      Mark Fasheh authored 
      We weren't reclaiming the clusters which get free'd from this function,
so any user punching holes in a file would still have those bytes accounted
against him/her. Add the call to vfs_dq_free_space_nodirty() to fix this.
Interestingly enough, the journal credits calculation already took this into
account.
Signed-off-by: default avatarMark Fasheh <mfasheh@suse.com>
Acked-by: default avatarJan Kara <jack@suse.cz>
      fd4ef231
    • Sunil Mushran's avatar
      ocfs2: Wakeup the downconvert thread after a successful cancel convert · a4b91965
      Sunil Mushran authored 
      When two nodes holding PR locks on a resource concurrently attempt to
upconvert the locks to EX, the master sends a BAST to one of the nodes. This
message tells that node to first cancel convert the upconvert request,
followed by downconvert to a NL. Only when this lock is downconverted to NL,
can the master upconvert the first node's lock to EX.

While the fs was doing the cancel convert, it was forgetting to wake up the
dc thread after a successful cancel, leading to a deadlock.
Reported-and-Tested-by: default avatarDavid Teigland <teigland@redhat.com>
Signed-off-by: default avatarSunil Mushran <sunil.mushran@oracle.com>
Signed-off-by: default avatarMark Fasheh <mfasheh@suse.com>
      a4b91965
    • Tao Ma's avatar
      ocfs2: Access the xattr bucket only before modifying it. · 554e7f9e
      Tao Ma authored 
      In ocfs2_xattr_value_truncate, we may call b-tree codes which will
extend the journal transaction. It has a potential problem that it
may let the already-accessed-but-not-dirtied buffers gone. So we'd
better access the bucket after we call ocfs2_xattr_value_truncate.
And as for the root buffer for the xattr value, b-tree code will
acess and dirty it, so we don't need to worry about it.
Signed-off-by: default avatarTao Ma <tao.ma@oracle.com>
Signed-off-by: default avatarMark Fasheh <mfasheh@suse.com>
      554e7f9e
    • Joel Becker's avatar
      configfs: Silence lockdep on mkdir(), rmdir() and configfs_depend_item() · 0e033342
      Joel Becker authored 
      When attaching default groups (subdirs) of a new group (in mkdir() or
in configfs_register()), configfs recursively takes inode's mutexes
along the path from the parent of the new group to the default
subdirs. This is needed to ensure that the VFS will not race with
operations on these sub-dirs. This is safe for the following reasons:

- the VFS allows one to lock first an inode and second one of its
  children (The lock subclasses for this pattern are respectively
  I_MUTEX_PARENT and I_MUTEX_CHILD);
- from this rule any inode path can be recursively locked in
  descending order as long as it stays under a single mountpoint and
  does not follow symlinks.

Unfortunately lockdep does not know (yet?) how to handle such
recursion.

I've tried to use Peter Zijlstra's lock_set_subclass() helper to
upgrade i_mutexes from I_MUTEX_CHILD to I_MUTEX_PARENT when we know
that we might recursively lock some of their descendant, but this
usage does not seem to fit the purpose of lock_set_subclass() because
it leads to several i_mutex locked with subclass I_MUTEX_PARENT by
the same task.

>From inside configfs it is not possible to serialize those recursive
locking with a top-level one, because mkdir() and rmdir() are already
called with inodes locked by the VFS. So using some
mutex_lock_nest_lock() is not an option.

I am proposing two solutions:
1) one that wraps recursive mutex_lock()s with
   lockdep_off()/lockdep_on().
2) (as suggested earlier by Peter Zijlstra) one that puts the
   i_mutexes recursively locked in different classes based on their
   depth from the top-level config_group created. This
   induces an arbitrary limit (MAX_LOCK_DEPTH - 2 == 46) on the
   nesting of configfs default groups whenever lockdep is activated
   but this limit looks reasonably high. Unfortunately, this alos
   isolates VFS operations on configfs default groups from the others
   and thus lowers the chances to detect locking issues.

This patch implements solution 1).

Solution 2) looks better from lockdep's point of view, but fails with
configfs_depend_item(). This needs to rework the locking
scheme of configfs_depend_item() by removing the variable lock recursion
depth, and I think that it's doable thanks to the configfs_dirent_lock.
For now, let's stick to solution 1).
Signed-off-by: default avatarLouis Rilling <louis.rilling@kerlabs.com>
Acked-by: default avatarJoel Becker <joel.becker@oracle.com>
Signed-off-by: default avatarMark Fasheh <mfasheh@suse.com>
      0e033342
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