xenbus: save xenstore local status for later use

Save the xenstore local status computed in xenbus_init. It can then be used
later to check if xenstored is running in this domain.

Signed-off-by: Aurelien Chartier <aurelien.chartier@citrix.com>
[Changes in v4:
- Change variable name to xen_store_domain_type]
Reviewed-by: David Vrabel <david.vrabel@citrix.com>
Signed-off-by: Konrad Rzeszutek Wilk <konrad.wilk@oracle.com>

3 files changed, 20 insertions, 15 deletions

diff --git a/drivers/xen/xenbus/xenbus_comms.h b/drivers/xen/xenbus/xenbus_comms.h
index c8abd3b8a6c4..e74f9c1fbd80 100644
--- a/drivers/xen/xenbus/xenbus_comms.h
+++ b/drivers/xen/xenbus/xenbus_comms.h
@@ -45,6 +45,7 @@ int xb_wait_for_data_to_read(void);
 int xs_input_avail(void);
 extern struct xenstore_domain_interface *xen_store_interface;
 extern int xen_store_evtchn;
+extern enum xenstore_init xen_store_domain_type;
 
 extern const struct file_operations xen_xenbus_fops;
 
diff --git a/drivers/xen/xenbus/xenbus_probe.c b/drivers/xen/xenbus/xenbus_probe.c
index 3325884c693f..56cfaaa9d006 100644
--- a/drivers/xen/xenbus/xenbus_probe.c
+++ b/drivers/xen/xenbus/xenbus_probe.c
@@ -69,6 +69,9 @@ EXPORT_SYMBOL_GPL(xen_store_evtchn);
 struct xenstore_domain_interface *xen_store_interface;
 EXPORT_SYMBOL_GPL(xen_store_interface);
 
+enum xenstore_init xen_store_domain_type;
+EXPORT_SYMBOL_GPL(xen_store_domain_type);
+
 static unsigned long xen_store_mfn;
 
 static BLOCKING_NOTIFIER_HEAD(xenstore_chain);
@@ -719,17 +722,11 @@ static int __init xenstored_local_init(void)
         return err;
 }
 
-enum xenstore_init {
-        UNKNOWN,
-        PV,
-        HVM,
-        LOCAL,
-};
 static int __init xenbus_init(void)
 {
         int err = 0;
-        enum xenstore_init usage = UNKNOWN;
         uint64_t v = 0;
+        xen_store_domain_type = XS_UNKNOWN;
 
         if (!xen_domain())
                 return -ENODEV;
@@ -737,29 +734,29 @@ static int __init xenbus_init(void)
         xenbus_ring_ops_init();
 
         if (xen_pv_domain())
-                usage = PV;
+                xen_store_domain_type = XS_PV;
         if (xen_hvm_domain())
-                usage = HVM;
+                xen_store_domain_type = XS_HVM;
         if (xen_hvm_domain() && xen_initial_domain())
-                usage = LOCAL;
+                xen_store_domain_type = XS_LOCAL;
         if (xen_pv_domain() && !xen_start_info->store_evtchn)
-                usage = LOCAL;
+                xen_store_domain_type = XS_LOCAL;
         if (xen_pv_domain() && xen_start_info->store_evtchn)
                 xenstored_ready = 1;
 
-        switch (usage) {
-        case LOCAL:
+        switch (xen_store_domain_type) {
+        case XS_LOCAL:
                 err = xenstored_local_init();
                 if (err)
                         goto out_error;
                 xen_store_interface = mfn_to_virt(xen_store_mfn);
                 break;
-        case PV:
+        case XS_PV:
                 xen_store_evtchn = xen_start_info->store_evtchn;
                 xen_store_mfn = xen_start_info->store_mfn;
                 xen_store_interface = mfn_to_virt(xen_store_mfn);
                 break;
-        case HVM:
+        case XS_HVM:
                 err = hvm_get_parameter(HVM_PARAM_STORE_EVTCHN, &v);
                 if (err)
                         goto out_error;
diff --git a/drivers/xen/xenbus/xenbus_probe.h b/drivers/xen/xenbus/xenbus_probe.h
index bb4f92ed8730..146f857a36f8 100644
--- a/drivers/xen/xenbus/xenbus_probe.h
+++ b/drivers/xen/xenbus/xenbus_probe.h
@@ -47,6 +47,13 @@ struct xen_bus_type {
         struct bus_type bus;
 };
 
+enum xenstore_init {
+        XS_UNKNOWN,
+        XS_PV,
+        XS_HVM,
+        XS_LOCAL,
+};
+
 extern struct device_attribute xenbus_dev_attrs[];
 
 extern int xenbus_match(struct device *_dev, struct device_driver *_drv);