[BLK] back: Only remove sysfs attributes if they were previously

added. Also check for errors during attribute creation.
Signed-off-by: Keir Fraser <keir@xensource.com>

diff --git a/linux-2.6-xen-sparse/drivers/xen/blkback/xenbus.c b/linux-2.6-xen-sparse/drivers/xen/blkback/xenbus.c
index f796c2f2c87be0d0b6e3b3d171e3183d2fb7e437..59d93242b5b203c45e6afb1a738774780da29607 100644 (file)
--- a/linux-2.6-xen-sparse/drivers/xen/blkback/xenbus.c
+++ b/linux-2.6-xen-sparse/drivers/xen/blkback/xenbus.c
@@ -109,7 +109,7 @@ VBD_SHOW(mode, "%s\n", be->mode);
 
 int xenvbd_sysfs_addif(struct xenbus_device *dev)
 {
-       int error = 0;
+       int error;
        
        error = device_create_file(&dev->dev, &dev_attr_physical_device);
        if (error)
@@ -157,7 +157,8 @@ static int blkback_remove(struct xenbus_device *dev)
                be->blkif = NULL;
        }
 
-       xenvbd_sysfs_delif(dev);
+       if (be->major || be->minor)
+               xenvbd_sysfs_delif(dev);
 
        kfree(be);
        dev->dev.driver_data = NULL;
@@ -272,13 +273,18 @@ static void backend_changed(struct xenbus_watch *watch,
                err = vbd_create(be->blkif, handle, major, minor,
                                 (NULL == strchr(be->mode, 'w')));
                if (err) {
-                       be->major = 0;
-                       be->minor = 0;
+                       be->major = be->minor = 0;
                        xenbus_dev_fatal(dev, err, "creating vbd structure");
                        return;
                }
 
-               xenvbd_sysfs_addif(dev);
+               err = xenvbd_sysfs_addif(dev);
+               if (err) {
+                       vbd_free(&be->blkif->vbd);
+                       be->major = be->minor = 0;
+                       xenbus_dev_fatal(dev, err, "creating sysfs entries");
+                       return;
+               }
 
                /* We're potentially connected now */
                update_blkif_status(be->blkif);