Following are revised versions of 6 patches from the v14 localio series. The issue addressed is net namespace refcounting. We don't want to keep a long-term counted reference in the client because that prevents a server container from completely shutting down. So we avoid taking a reference at all and rely on the per-cpu reference to the server being sufficient to keep the net-ns active. This involves allowing the net-ns exit code to iterate all active clients and clear their ->net pointers (which they need to find the per-cpu-refcount for the nfs_serv). So: - embed nfs_uuid_t in nfs_client. This provides a list_head that can be used to find the client. It does add the actual uuid to nfs_client so it is bigger than needed. If that is really a problem we can find a fix. - When the nfs server confirms that the uuid is local, it moves the nfs_uuid_t onto a per-net-ns list. - When the net-ns is shutting down - in a "pre_exit" handler, all these nfS_uuid_t have their ->net cleared. There is an rcu_synchronize() call between pre_exit() handlers and exit() handlers so and caller that sees ->net as not NULL can safely check the ->counter - We now pass the nfs_uuid_t to nfsd_open_local_fh() so it can safely look at ->net in a private rcu_read_lock() section. I have compile tested this code but nothing more. Thanks, NeilBrown [PATCH 14/25] nfs_common: add NFS LOCALIO auxiliary protocol [PATCH 15/25] nfs_common: introduce nfs_localio_ctx struct and [PATCH 16/25] nfsd: add localio support [PATCH 17/25] nfsd: implement server support for NFS_LOCALIO_PROGRAM [PATCH 19/25] nfs: add localio support [PATCH 23/25] nfs: implement client support for NFS_LOCALIO_PROGRAM
