`On Thu, Jan 13, 2005 at 06:30:50PM -0500, Mike Waychison wrote:> > 1) each p-node corresponds to a group of 1 or more vfsmounts.> > 2) there is at most 1 p-node containing a given vfsmount.> > 3) each p-node owns a possibly empty set of p-nodes and vfsmounts> > 4) no p-node or vfsmount can be owned by more than one p-node> > 5) only vfsmounts that are not contained in any p-nodes might be owned.> > 6) no p-node can own (directly or via intermediates) itself (i.e. the> > graph of p-node ownership is a forest).> > > > These guys define propagation:> > 	a) if vfsmounts A and B are contained in the same p-node, events> > propagate from A to B> > 	b) if vfsmount A is contained in p-node p, vfsmount B is contained> > in p-node q and p owns q, events propagate from A to B> > 	c) if vfsmount A is contained in p-node p and vfsmount B is owned> > by p, events propagate from A to B> > How is (c) different from (a)? Is there a distinction between> 'containing' and 'owning' here?Yes.  See (3) and (1) above.  Consider the following:p = {A, B}p owns CThen we have propagation between A and B _and_ from either to C.> > 	* we can mark a subtree slave.  That removes all vfsmounts in> > the subtree from their p-nodes and makes them owned by said p-nodes.> > p-nodes that became empty will disappear and everything they used to> > own will be repossessed by their owners (if any).> > Would this be better read as "That removes each vfsmount A in the> subtree from its respective p-node p and makes it contained by a new> p-node p' (containing only A), and p' becomes 'owned' by p." ?No.  "Belongs to a single-element p-node" != "doesn't belong to anyp-node".  The former means "share on copy" (and might have slaves).The latter is noone's master.  Again, see the propagation rules andbehaviour on clone/rbind.> > 	* if V is contained in some p-node p, A is placed into the same> > p-node.  That may require merging one of the p-nodes we'd just created> > with p (that will be the counterpart of the p-node containing the mountpoint).> > 	* if V is owned by some p-node p, then A (or p-node containing A)> > becomes owned by p.> > I don't follow this.  I still don't see the distinction between being> owned and being contained.  Also, for statements like 'A belongs to B',> which is it?"V owned by p" == "V is a slave of (equivelent) members of p""p contains V" == "V is one of the members of p, whatever happens to itwill happen to all of them"."element belongs to set" means what it usually means ;-) (again, p-nodesare sets of vfsmounts).-To unsubscribe from this list: send the line "unsubscribe linux-kernel" inthe body of a message to majordomo@vger.kernel.orgMore majordomo info at  http://vger.kernel.org/majordomo-info.htmlPlease read the FAQ at  http://www.tux.org/lkml/`