On Mon, 2008-09-08 at 22:27 -0600, Matthew Wilcox wrote: > On Mon, Sep 08, 2008 at 09:12:29PM -0700, Jesse Barnes wrote: > > I don't have a preference here; whatever is most useful for people is probably > > what we should go for. Zhao? > > I think we have two distinct groups of users; those who find emulating > slot hotplug useful, and those who want to hot-remove pci functions. > Maybe hot-removing a pci function should not be part of the pci hotplug > core per se -- obviously it would share much code -- but being able > to hot-remove a function is a fundamentally different thing from being > able to hot-remove a slot. For example, hot-removing a function from a > device that is in a real hotplug slot should be possible, but it wouldn't > involve the driver for that hotplug slot. > > So maybe what we want is a /sys/bus/pci/devices/dddd:bb:dd.f/remove file > that does just that. > of something like "disable", so we can enable it again? > Oh, and we also want a way to hot-add functions, not necessarily even > ones that have been removed from the machine after it was booted, but > those that show up after the machine has booted. For example, one of > my former colleagues had a laptop which would remove the wireless pci > device from the bus if the rfkill switch was enabled. I remember there > was a hack to load a module that called some pci bus rescan functionality. > I didn't look into it in much detail. > > I don't have a firm idea about an interface for this. SCSI handles it by > writing scsi-add-single-device H C T L to /proc/scsi/scsi. Maybe we want > a /sys/bus/pci/scan or /sys/bus/pci/devices/scan file that we can echo > "0000:01:02.3" to scan just that function, or "0000:01:02" to scan the > device. > I like this idea. Even perhaps add a recursive scan to rescan behind a bridge? -- Andrew Patterson Hewlett-Packard -- To unsubscribe from this list: send the line "unsubscribe linux-pci" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
