Il 19/10/2012 14:44, Markus Armbruster ha scritto: > Apropos hotplug. The only way to unexport a block device is to stop the > NBD server outright. Once the device backend has been exported, > unplugging the device gets rid of the frontend, but the backend stays > until you stop the NBD server, or you kill the backend with the big > drive_del hammer.
Right. (Though for removable devices you can just eject it, which calls the close notifier). > Makes me wonder whether we need QMP command nbd-server-del. Perhaps yes, but it can be added later. > I agree that we can the human monitor is again for human users only, > thus we don't have to encumber it with the need of tools. I might also > buy your argument that extra exports don't really hurt. But device plug > / -unplug is just as relevant there as in QMP. If it's a show-stopper > for QMP, then I don't think it can be a "minor loss" for HMP. The question is, who do we expect to use HMP at this time? > 2. What if we ever change our minds regarding fine-grained NBD export > control in the human monitor? Add a second command to start the server > without exporting everything? Add a "don't auto-export" argument to the > existing command? The latter. But indeed one alternative, possibly better, is to remove the auto-add and add a "nbd_server_add -a" (for "all") flag to HMP. I think I'll drop the last patch and send a pull request for the others (with your suggested changes), while we discuss this. Paolo
