On Fri, Feb 27, 2015 at 8:41 AM, Michael Roth <mdr...@linux.vnet.ibm.com> wrote:
> +static void attach(sPAPRDRConnector *drc, DeviceState *d, void *fdt,
> + int fdt_start_offset, bool coldplug, Error **errp)
> +{
> + DPRINTFN("drc: %x, attach", get_index(drc));
> +
> + if (drc->isolation_state != SPAPR_DR_ISOLATION_STATE_ISOLATED) {
> + error_setg(errp, "an attached device is still awaiting release");
> + return;
> + }
> + g_assert(drc->allocation_state == SPAPR_DR_ALLOCATION_STATE_UNUSABLE);
> + g_assert(fdt || coldplug);
> +
> + /* NOTE: setting initial isolation state to UNISOLATED means we can't
> + * detach unless guest has a userspace/kernel that moves this state
> + * back to ISOLATED in response to an unplug event, or this is done
> + * manually by the admin prior. if we force things while the guest
> + * may be accessing the device, we can easily crash the guest, so we
> + * we defer completion of removal in such cases to the reset() hook.
> + */
> + drc->isolation_state = SPAPR_DR_ISOLATION_STATE_UNISOLATED;
> + drc->allocation_state = SPAPR_DR_ALLOCATION_STATE_USABLE;
BTW shouldn't isolation_state and allocation_state be set to
UNISOLATED and USABLE in response to guest's rtas-set-indicator calls
? At least, that is how it is done/expected for CPU hotplug case. Ref:
kernel code arch/powerpc/platforms/pseries/dlpar.c:
dlpar_acquire[release]_drc().
Same question for detach().
Regards,
Bharata.
