On Sat, Aug 11, 2012 at 03:15:24PM +0400, Stanislav Kinsbursky wrote: > 11.08.2012 10:23, Pavel Emelyanov пишет: > >On 08/11/2012 03:09 AM, H. Peter Anvin wrote: > >>On 08/10/2012 12:28 PM, Alan Cox wrote: > >>>Explicitly for Linux yes - this is not generally true of the AF_UNIX > >>>socket domain and even the permissions aspect isn't guaranteed to be > >>>supported on some BSD environments ! > >>Yes, but let's worry about what the Linux behavior should be. > >> > >>>The name is however just a proxy for the socket itself. You don't even > >>>get a device node in the usual sense or the same inode in the file system > >>>space. > >> > >>No, but it is looked up the same way any other inode is (the difference > >>between FIFOs and sockets is that sockets have separate connections, > >>which is also why open() on sockets would be nice.) > >> > >>However, there is a fundamental difference between AF_UNIX sockets and > >>open(), and that is how the pathname is delivered. It thus would make > >>more sense to provide the openat()-like information in struct > >>sockaddr_un, but that may be very hard to do in a sensible way. In that > >>sense it perhaps would be cleaner to be able to do an open[at]() on the > >>socket node with O_PATH (perhaps there should be an O_SOCKET option, > >>even?) and pass the resulting file descriptor to bind() or connect(). > >I vote for this (openat + O_WHATEVER on a unix socket) as well. It will > >help us in checkpoint-restore, making handling of overmounted/unlinked > >sockets much cleaner. > > I have to notice, that it's not enough and doesn't solve the issue. > There should be some way how to connect/bind already existent unix > socket (from kernel, at least), because socket can be created in > user space. > And this way (sock operation or whatever) have to provide an ability > to lookup UNIX socket starting from specified root to support > containers. I don't understand--the rpcbind sockets are created by the kernel. What am I missing? --b. -- 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
