On Mon, Jan 17, 2011 at 06:30:16AM -0600, Rob Landley wrote: > On 01/14/2011 07:48 AM, Kirill A. Shutemov wrote: > > Prepare nfs/sunrpc stack to use multiple instances of rpc_pipefs. > > Only for client for now. > > Ok, Google is being really unhelpful here. It's better if you read the code. :) > > What is rpc_pipefs for? What uses it, and to do what exactly? Is it > used by nfs server code, or by the client code, or both? Is it a way > for userspace to talk to the kernel, or for the kernel to talk to > itself? Is it used at mount time, or during filesystem operation? Ok, It try to answer. Please correct me, if I'm wrong. rpc_pipefs is a userland/kernel interface (I don't see kernel-kernel usecases, but it's possible, I guess). There is client dir (nfs/clntX) in rpc_pipefs for every sunrpc client. Both client and server (see fs/nfsd/nfs4callback.c) can create sunrpc client. So we rpc_pipefs on both side. rpc_pipefs uses not only on mount time. See old idmapper, for example. > I'm interested in giving this patch series a much more thorough review, > but I can't figure out what the subsystem it's modifying actually _is_. > > (Maybe this is something to do with filesystems/nfs/rpc-cache.txt?) > > Rob -- Kirill A. Shutemov -- To unsubscribe from this list: send the line "unsubscribe linux-nfs" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
