On Wed, 2 Dec 2009, Alan Cox wrote: > > You're still missing the point. O_NODE is like a hard link, except > > the reference doesn't come from the filesystem but from a file > > descriptor. From udev's perspective there's no difference. > > I don't think I am missing the point here. You have a reference to an > object in the fs but you don't have a reference to the driver underneath > s the driver can change on you *while* you have the O_NODE open and fd > live. That cannot happen with a hard link and open. > > It isn't the same thing as far as I can see. You don't have the barrier > between the operations that occurs in the real open/close case because > they lock the driver. The file descriptor opened with O_NODE allows exaclactly the same operations that a hard link to the device would, nothing more. It's just a link to the *node*, except it doesn't increment the link count, the driver is irrelevant. Miklos -- To unsubscribe from this list: send the line "unsubscribe linux-fsdevel" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
