James, Mike, or anyone else: I've got a few questions regarding the state model and "soft" (i.e., notified) host removals. First, concerning the SHOST_STATE_* values... Although there is an elaborate state machine which allows only selected transitions, and although the value can be viewed and changed via sysfs -- nevertheless, the value is actually _used_ in only two places: scsi_host_get() fails if the state is SHOST_STATE_DEL, and ditto for scsi_dispatch_cmd(). Did I miss something? This suggests that the state machinery may be a lot more complicated than truly necessary. Should it be simplified? (Side note: Back near the end of 2004 (?), there was an extended discussion on the state model, eventually leading to the creation of the SHOST_DEL_RECOVERY state. I'm unable to locate that thread in an email archive, which is a shame because it included some very nice descriptions of the meaning of the various states and the allowed transitions. There isn't anything in Documentation/scsi with a comparable explanation -- and there certainly ought to be. Can you locate those old email messages?) Second, concerning soft host removal... I have in mind a situation where a user wants to unbind usb-storage from a device in a clean, safe manner, without unplugging anything. Existing commands should be allowed to complete, caches should be flushed, and so on. Is there any way to do this? It used to be that scsi_remove_host() would cancel all outstanding commands. Isn't that still true? If so, is there any way to accomplish what I want? Thanks, Alan Stern -- To unsubscribe from this list: send the line "unsubscribe linux-scsi" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
