[Cluster-devel] gfs uevent and sysfs changes

[David Teigland <teigland@redhat.com>]

Here are the compatibility aspects to the recent ideas about changes to
the user/kernel interface between gfs (1 & 2) and gfs_controld.

. gfs_controld can remove id from hostdata string in mount options

  - no compat issues AFAICT

. getting rid of "id" sysfs file from lock_dlm

  - new gfs_controld old gfs-kernel
    old kernel provides both "block" and "id" sysfs files
    new daemon looks for "block" instead of "id" in sysfs

  - old gfs_controld new gfs-kernel
    old daemon looks for "id" sysfs file
    new kernel needs to provide "id" as well as "block" sysfs files

  Once everyone is using the new daemon, we can remove the "id" sysfs
  file from the kernel.

. uevent strings to replace recover_done/recover_status sysfs files

  - new gfs_controld old gfs-kernel
    old kernel has recover sysfs files, and no new uevent strings
    new daemon needs to look for either sysfs files or uevent strings

  - old gfs_controld new gfs-kernel
    old daemon looks for recover sysfs files, not new uevent strings
    new kernel needs to provide both sysfs files and uevent strings

  Once everyone is using new kernel and new daemon, we can remove
  the recover sysfs files from kernel, and daemon can stop looking for
  recover sysfs files.