1. 07 Feb, 2008 1 commit
    • Joel Becker's avatar
      ocfs2: Negotiate locking protocol versions. · d24fbcda
      Joel Becker authored
      Currently, when ocfs2 nodes connect via TCP, they advertise their
      compatibility level.  If the versions do not match, two nodes cannot speak
      to each other and they disconnect. As a result, this provides no forward or
      backwards compatibility.
      
      This patch implements a simple protocol negotiation at the dlm level by
      introducing a major/minor version number scheme for entities that
      communicate.  Specifically, o2dlm has a major/minor version for interaction
      with o2dlm on other nodes, and ocfs2 itself has a major/minor version for
      interacting with the filesystem on other nodes.
      
      This will allow rolling upgrades of ocfs2 clusters when changes to the
      locking or network protocols can be done in a backwards compatible manner.
      In those cases, only the minor number is changed and the negotatied protocol
      minor is returned from dlm join. In the far less likely event that a
      required protocol change makes backwards compatibility impossible, we simply
      bump the major number.
      Signed-off-by: default avatarJoel Becker <joel.becker@oracle.com>
      Signed-off-by: default avatarMark Fasheh <mark.fasheh@oracle.com>
      d24fbcda
  2. 06 Feb, 2008 39 commits