[S390] add PAV support to the dasd driver.

Add support for parallel-access-volumes to the dasd driver. This
allows concurrent access to dasd devices with multiple channel
programs.

Signed-off-by: Horst Hummel <horst.hummel@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>

1 files changed, 23 insertions, 28 deletions

diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 7e9978ad1445..bafcd2f20ae2 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -1855,15 +1855,34 @@ dasd_generic_probe (struct ccw_device *cdev,
 {
         int ret;
 
+        ret = ccw_device_set_options(cdev, CCWDEV_DO_PATHGROUP);
+        if (ret) {
+                printk(KERN_WARNING
+                       "dasd_generic_probe: could not set ccw-device options "
+                       "for %s\n", cdev->dev.bus_id);
+                return ret;
+        }
         ret = dasd_add_sysfs_files(cdev);
         if (ret) {
                 printk(KERN_WARNING
                        "dasd_generic_probe: could not add sysfs entries "
                        "for %s\n", cdev->dev.bus_id);
-        } else {
-                cdev->handler = &dasd_int_handler;
+                return ret;
         }
+        cdev->handler = &dasd_int_handler;
 
+        /*
+         * Automatically online either all dasd devices (dasd_autodetect)
+         * or all devices specified with dasd= parameters during
+         * initial probe.
+         */
+        if ((dasd_get_feature(cdev, DASD_FEATURE_INITIAL_ONLINE) > 0 ) ||
+            (dasd_autodetect && dasd_busid_known(cdev->dev.bus_id) != 0))
+                ret = ccw_device_set_online(cdev);
+        if (ret)
+                printk(KERN_WARNING
+                       "dasd_generic_probe: could not initially online "
+                       "ccw-device %s\n", cdev->dev.bus_id);
         return ret;
 }
 
@@ -1911,6 +1930,8 @@ dasd_generic_set_online (struct ccw_device *cdev,
         struct dasd_device *device;
         int rc;
 
+        /* first online clears initial online feature flag */
+        dasd_set_feature(cdev, DASD_FEATURE_INITIAL_ONLINE, 0);
         device = dasd_create_device(cdev);
         if (IS_ERR(device))
                 return PTR_ERR(device);
@@ -2065,31 +2086,6 @@ dasd_generic_notify(struct ccw_device *cdev, int event)
         return ret;
 }
 
-/*
- * Automatically online either all dasd devices (dasd_autodetect) or
- * all devices specified with dasd= parameters.
- */
-static int
-__dasd_auto_online(struct device *dev, void *data)
-{
-        struct ccw_device *cdev;
-
-        cdev = to_ccwdev(dev);
-        if (dasd_autodetect || dasd_busid_known(cdev->dev.bus_id) == 0)
-                ccw_device_set_online(cdev);
-        return 0;
-}
-
-void
-dasd_generic_auto_online (struct ccw_driver *dasd_discipline_driver)
-{
-        struct device_driver *drv;
-
-        drv = get_driver(&dasd_discipline_driver->driver);
-        driver_for_each_device(drv, NULL, NULL, __dasd_auto_online);
-        put_driver(drv);
-}
-
 
 static int __init
 dasd_init(void)
@@ -2170,5 +2166,4 @@ EXPORT_SYMBOL_GPL(dasd_generic_remove);
 EXPORT_SYMBOL_GPL(dasd_generic_notify);
 EXPORT_SYMBOL_GPL(dasd_generic_set_online);
 EXPORT_SYMBOL_GPL(dasd_generic_set_offline);
-EXPORT_SYMBOL_GPL(dasd_generic_auto_online);