nfs: store devname at disconnected NFS roots
part 2: make sure that disconnected roots have corresponding mnt_devname
values stashed into them.
Have nfs*_get_root() stuff a copy of devname into ->d_fsdata of the
found root, provided that it is disconnected.
Have ->d_release() free it when dentry goes away.
Have the places where NFS uses ->d_fsdata for sillyrename (and that
can *never* happen to a disconnected root - dentry will be attached
to its parent) free old devname copies if they find those.
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
3 files changed