[POWERPC] iSeries: improve viodasd initialisation

On error, make sure that we undo all necessary operations.

This also gets rid of a must_check warning.

Signed-off-by: Stephen Rothwell <sfr@canb.auug.org.au>
Signed-off-by: Paul Mackerras <paulus@samba.org>

diff --git a/drivers/block/viodasd.c b/drivers/block/viodasd.c
index ec5a1b90a0a24133d1043fb19290a1d296b11125..e19ba4ebcd4e2c4763c926bfae4be82135962c0a 100644 (file)
--- a/drivers/block/viodasd.c
+++ b/drivers/block/viodasd.c
@@ -759,6 +759,8 @@ static struct vio_driver viodasd_driver = {
        }
 };
 
+static int need_delete_probe;
+
 /*
  * Initialize the whole device driver.  Handle module and non-module
  * versions
@@ -773,46 +775,67 @@ static int __init viodasd_init(void)
 
        if (viopath_hostLp == HvLpIndexInvalid) {
                printk(VIOD_KERN_WARNING "invalid hosting partition\n");
-               return -EIO;
+               rc = -EIO;
+               goto early_fail;
        }
 
        printk(VIOD_KERN_INFO "vers " VIOD_VERS ", hosting partition %d\n",
                        viopath_hostLp);
 
         /* register the block device */
-       if (register_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME)) {
+       rc =  register_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
+       if (rc) {
                printk(VIOD_KERN_WARNING
                                "Unable to get major number %d for %s\n",
                                VIODASD_MAJOR, VIOD_GENHD_NAME);
-               return -EIO;
+               goto early_fail;
        }
        /* Actually open the path to the hosting partition */
-       if (viopath_open(viopath_hostLp, viomajorsubtype_blockio,
-                               VIOMAXREQ + 2)) {
+       rc = viopath_open(viopath_hostLp, viomajorsubtype_blockio,
+                               VIOMAXREQ + 2);
+       if (rc) {
                printk(VIOD_KERN_WARNING
                       "error opening path to host partition %d\n",
                       viopath_hostLp);
-               unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
-               return -EIO;
+               goto unregister_blk;
        }
 
        /* Initialize our request handler */
        vio_setHandler(viomajorsubtype_blockio, handle_block_event);
 
        rc = vio_register_driver(&viodasd_driver);
-       if (rc == 0)
-               driver_create_file(&viodasd_driver.driver, &driver_attr_probe);
+       if (rc) {
+               printk(VIOD_KERN_WARNING "vio_register_driver failed\n");
+               goto unset_handler;
+       }
+
+       /*
+        * If this call fails, it just means that we cannot dynamically
+        * add virtual disks, but the driver will still work fine for
+        * all existing disk, so ignore the failure.
+        */
+       if (!driver_create_file(&viodasd_driver.driver, &driver_attr_probe))
+               need_delete_probe = 1;
+
+       return 0;
+
+unset_handler:
+       vio_clearHandler(viomajorsubtype_blockio);
+       viopath_close(viopath_hostLp, viomajorsubtype_blockio, VIOMAXREQ + 2);
+unregister_blk:
+       unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
+early_fail:
        return rc;
 }
 module_init(viodasd_init);
 
-void viodasd_exit(void)
+void __exit viodasd_exit(void)
 {
-       driver_remove_file(&viodasd_driver.driver, &driver_attr_probe);
+       if (need_delete_probe)
+               driver_remove_file(&viodasd_driver.driver, &driver_attr_probe);
        vio_unregister_driver(&viodasd_driver);
        vio_clearHandler(viomajorsubtype_blockio);
-       unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
        viopath_close(viopath_hostLp, viomajorsubtype_blockio, VIOMAXREQ + 2);
+       unregister_blkdev(VIODASD_MAJOR, VIOD_GENHD_NAME);
 }
-
 module_exit(viodasd_exit);