git: DragonFly_RELEASE_3_0 VFS accounting: check if nullfs mp* really exist

Francois Tigeot ftigeot at
Sat Feb 18 01:12:26 PST 2012

commit e6a2de8892f82243ea8672b974cb8d190c0bc35d
Author: Francois Tigeot <ftigeot at>
Date:   Fri Feb 17 23:58:58 2012 +0100

    VFS accounting: check if nullfs mp* really exist
    * Nullfs are a clever hack, they forget their mp after mount and let the
      non-nullfs underlying mount point do all the work
    * Nevertheless, we need to get the real struct mount associated to a mount
      point to count the space used by PFSes. We cache it in the vnode.
    * But since the vnode we use really belongs to the lowest underlying
      mount point, the upper-level mp may already have been freed.
    * We need to first check if it still valid; a new function,
      mountlist_exists() now exists for that purpose.
    * Should fix issue #2266

Summary of changes:
 sys/kern/vfs_mount.c  |   23 +++++++++++++++++++++++
 sys/kern/vfs_vopops.c |    5 ++++-
 sys/sys/mount.h       |    1 +
 3 files changed, 28 insertions(+), 1 deletions(-)

DragonFly BSD source repository

More information about the Commits mailing list