diff options
| -rw-r--r-- | hw/xen/trace-events | 2 | ||||
| -rw-r--r-- | hw/xen/xen-bus.c | 94 | ||||
| -rw-r--r-- | include/hw/xen/xen-bus.h | 3 |
3 files changed, 74 insertions, 25 deletions
diff --git a/hw/xen/trace-events b/hw/xen/trace-events index 80ce3da..e6885bc 100644 --- a/hw/xen/trace-events +++ b/hw/xen/trace-events @@ -17,8 +17,10 @@ xen_domid_restrict(int err) "err: %u" xen_bus_realize(void) "" xen_bus_unrealize(void) "" xen_bus_enumerate(void) "" +xen_bus_cleanup(void) "" xen_bus_type_enumerate(const char *type) "type: %s" xen_bus_backend_create(const char *type, const char *path) "type: %s path: %s" +xen_bus_device_cleanup(const char *type, char *name) "type: %s name: %s" xen_bus_add_watch(const char *node, const char *key) "node: %s key: %s" xen_bus_remove_watch(const char *node, const char *key) "node: %s key: %s" xen_device_realize(const char *type, char *name) "type: %s name: %s" diff --git a/hw/xen/xen-bus.c b/hw/xen/xen-bus.c index 810a4e2..55c1573 100644 --- a/hw/xen/xen-bus.c +++ b/hw/xen/xen-bus.c @@ -340,13 +340,18 @@ static void xen_bus_type_enumerate(XenBus *xenbus, const char *type) for (i = 0; i < n; i++) { char *backend_path = g_strdup_printf("%s/%s", domain_path, backend[i]); - enum xenbus_state backend_state; + enum xenbus_state state; + unsigned int online; if (xs_node_scanf(xenbus->xsh, XBT_NULL, backend_path, "state", - NULL, "%u", &backend_state) != 1) - backend_state = XenbusStateUnknown; + NULL, "%u", &state) != 1) + state = XenbusStateUnknown; - if (backend_state == XenbusStateInitialising) { + if (xs_node_scanf(xenbus->xsh, XBT_NULL, backend_path, "online", + NULL, "%u", &online) != 1) + online = 0; + + if (online && state == XenbusStateInitialising) { Error *local_err = NULL; xen_bus_backend_create(xenbus, type, backend[i], backend_path, @@ -365,9 +370,8 @@ out: g_free(domain_path); } -static void xen_bus_enumerate(void *opaque) +static void xen_bus_enumerate(XenBus *xenbus) { - XenBus *xenbus = opaque; char **type; unsigned int i, n; @@ -385,6 +389,45 @@ static void xen_bus_enumerate(void *opaque) free(type); } +static void xen_bus_device_cleanup(XenDevice *xendev) +{ + const char *type = object_get_typename(OBJECT(xendev)); + Error *local_err = NULL; + + trace_xen_bus_device_cleanup(type, xendev->name); + + g_assert(!xendev->backend_online); + + if (!xen_backend_try_device_destroy(xendev, &local_err)) { + object_unparent(OBJECT(xendev)); + } + + if (local_err) { + error_report_err(local_err); + } +} + +static void xen_bus_cleanup(XenBus *xenbus) +{ + XenDevice *xendev, *next; + + trace_xen_bus_cleanup(); + + QLIST_FOREACH_SAFE(xendev, &xenbus->inactive_devices, list, next) { + g_assert(xendev->inactive); + QLIST_REMOVE(xendev, list); + xen_bus_device_cleanup(xendev); + } +} + +static void xen_bus_backend_changed(void *opaque) +{ + XenBus *xenbus = opaque; + + xen_bus_enumerate(xenbus); + xen_bus_cleanup(xenbus); +} + static void xen_bus_unrealize(BusState *bus, Error **errp) { XenBus *xenbus = XEN_BUS(bus); @@ -433,7 +476,7 @@ static void xen_bus_realize(BusState *bus, Error **errp) xenbus->backend_watch = xen_bus_add_watch(xenbus, "", /* domain root node */ - "backend", xen_bus_enumerate, &local_err); + "backend", xen_bus_backend_changed, &local_err); if (local_err) { /* This need not be treated as a hard error so don't propagate */ error_reportf_err(local_err, @@ -555,9 +598,9 @@ static void xen_device_backend_set_online(XenDevice *xendev, bool online) * Tell from the state whether the frontend is likely alive, * i.e. it will react to a change of state of the backend. */ -static bool xen_device_state_is_active(enum xenbus_state state) +static bool xen_device_frontend_is_active(XenDevice *xendev) { - switch (state) { + switch (xendev->frontend_state) { case XenbusStateInitWait: case XenbusStateInitialised: case XenbusStateConnected: @@ -594,30 +637,31 @@ static void xen_device_backend_changed(void *opaque) * state to Closing, but there is no active frontend then set the * backend state to Closed. */ - if (xendev->backend_state == XenbusStateClosing && - !xen_device_state_is_active(xendev->frontend_state)) { + if (state == XenbusStateClosing && + !xen_device_frontend_is_active(xendev)) { xen_device_backend_set_state(xendev, XenbusStateClosed); } /* * If a backend is still 'online' then we should leave it alone but, - * if a backend is not 'online', then the device should be destroyed - * once the state is Closed. + * if a backend is not 'online', then the device is a candidate + * for destruction. Hence add it to the 'inactive' list to be cleaned + * by xen_bus_cleanup(). */ - if (!xendev->backend_online && - (xendev->backend_state == XenbusStateClosed || - xendev->backend_state == XenbusStateInitialising || - xendev->backend_state == XenbusStateInitWait || - xendev->backend_state == XenbusStateUnknown)) { - Error *local_err = NULL; + if (!online && + (state == XenbusStateClosed || state == XenbusStateInitialising || + state == XenbusStateInitWait || state == XenbusStateUnknown) && + !xendev->inactive) { + XenBus *xenbus = XEN_BUS(qdev_get_parent_bus(DEVICE(xendev))); - if (!xen_backend_try_device_destroy(xendev, &local_err)) { - object_unparent(OBJECT(xendev)); - } + xendev->inactive = true; + QLIST_INSERT_HEAD(&xenbus->inactive_devices, xendev, list); - if (local_err) { - error_report_err(local_err); - } + /* + * Re-write the state to cause a XenBus backend_watch notification, + * resulting in a call to xen_bus_cleanup(). + */ + xen_device_backend_printf(xendev, "state", "%u", state); } } diff --git a/include/hw/xen/xen-bus.h b/include/hw/xen/xen-bus.h index 0d19814..3d55322 100644 --- a/include/hw/xen/xen-bus.h +++ b/include/hw/xen/xen-bus.h @@ -32,7 +32,9 @@ typedef struct XenDevice { XenWatch *backend_online_watch; xengnttab_handle *xgth; bool feature_grant_copy; + bool inactive; QLIST_HEAD(, XenEventChannel) event_channels; + QLIST_ENTRY(XenDevice) list; } XenDevice; typedef char *(*XenDeviceGetName)(XenDevice *xendev, Error **errp); @@ -68,6 +70,7 @@ typedef struct XenBus { struct xs_handle *xsh; XenWatchList *watch_list; XenWatch *backend_watch; + QLIST_HEAD(, XenDevice) inactive_devices; } XenBus; typedef struct XenBusClass { |