X-Git-Url: http://git.onelab.eu/?a=blobdiff_plain;f=drivers%2Fs390%2Fcio%2Fcss.c;h=13eeea3d547f2be83a1c8b9e8ca6139d6c858c9f;hb=16c70f8c1b54b61c3b951b6fb220df250fe09b32;hp=74ea8aac4b7d9683c37ce79e79a41edf673b9d07;hpb=4e76c8a9fa413ccc09d3f7f664183dcce3555d57;p=linux-2.6.git

diff --git a/drivers/s390/cio/css.c b/drivers/s390/cio/css.c
index 74ea8aac4..13eeea3d5 100644
--- a/drivers/s390/cio/css.c
+++ b/drivers/s390/cio/css.c
@@ -19,9 +19,11 @@
 #include "cio_debug.h"
 #include "ioasm.h"
 #include "chsc.h"
+#include "device.h"
 
 int need_rescan = 0;
 int css_init_done = 0;
+static int need_reprobe = 0;
 static int max_ssid = 0;
 
 struct channel_subsystem *css[__MAX_CSSID + 1];
@@ -106,6 +108,24 @@ css_subchannel_release(struct device *dev)
 
 extern int css_get_ssd_info(struct subchannel *sch);
 
+
+int css_sch_device_register(struct subchannel *sch)
+{
+	int ret;
+
+	mutex_lock(&sch->reg_mutex);
+	ret = device_register(&sch->dev);
+	mutex_unlock(&sch->reg_mutex);
+	return ret;
+}
+
+void css_sch_device_unregister(struct subchannel *sch)
+{
+	mutex_lock(&sch->reg_mutex);
+	device_unregister(&sch->dev);
+	mutex_unlock(&sch->reg_mutex);
+}
+
 static int
 css_register_subchannel(struct subchannel *sch)
 {
@@ -117,7 +137,7 @@ css_register_subchannel(struct subchannel *sch)
 	sch->dev.release = &css_subchannel_release;
 	
 	/* make it known to the system */
-	ret = device_register(&sch->dev);
+	ret = css_sch_device_register(sch);
 	if (ret)
 		printk (KERN_WARNING "%s: could not register %s\n",
 			__func__, sch->dev.bus_id);
@@ -248,7 +268,7 @@ css_evaluate_subchannel(struct subchannel_id schid, int slow)
 		 * The device will be killed automatically.
 		 */
 		cio_disable_subchannel(sch);
-		device_unregister(&sch->dev);
+		css_sch_device_unregister(sch);
 		/* Reset intparm to zeroes. */
 		sch->schib.pmcw.intparm = 0;
 		cio_modify(sch);
@@ -262,7 +282,7 @@ css_evaluate_subchannel(struct subchannel_id schid, int slow)
 		 * away in any case.
 		 */
 		if (!disc) {
-			device_unregister(&sch->dev);
+			css_sch_device_unregister(sch);
 			/* Reset intparm to zeroes. */
 			sch->schib.pmcw.intparm = 0;
 			cio_modify(sch);
@@ -339,6 +359,67 @@ typedef void (*workfunc)(void *);
 DECLARE_WORK(slow_path_work, (workfunc)css_trigger_slow_path, NULL);
 struct workqueue_struct *slow_path_wq;
 
+/* Reprobe subchannel if unregistered. */
+static int reprobe_subchannel(struct subchannel_id schid, void *data)
+{
+	struct subchannel *sch;
+	int ret;
+
+	CIO_DEBUG(KERN_INFO, 6, "cio: reprobe 0.%x.%04x\n",
+		  schid.ssid, schid.sch_no);
+	if (need_reprobe)
+		return -EAGAIN;
+
+	sch = get_subchannel_by_schid(schid);
+	if (sch) {
+		/* Already known. */
+		put_device(&sch->dev);
+		return 0;
+	}
+
+	ret = css_probe_device(schid);
+	switch (ret) {
+	case 0:
+		break;
+	case -ENXIO:
+	case -ENOMEM:
+		/* These should abort looping */
+		break;
+	default:
+		ret = 0;
+	}
+
+	return ret;
+}
+
+/* Work function used to reprobe all unregistered subchannels. */
+static void reprobe_all(void *data)
+{
+	int ret;
+
+	CIO_MSG_EVENT(2, "reprobe start\n");
+
+	need_reprobe = 0;
+	/* Make sure initial subchannel scan is done. */
+	wait_event(ccw_device_init_wq,
+		   atomic_read(&ccw_device_init_count) == 0);
+	ret = for_each_subchannel(reprobe_subchannel, NULL);
+
+	CIO_MSG_EVENT(2, "reprobe done (rc=%d, need_reprobe=%d)\n", ret,
+		      need_reprobe);
+}
+
+DECLARE_WORK(css_reprobe_work, reprobe_all, NULL);
+
+/* Schedule reprobing of all unregistered subchannels. */
+void css_schedule_reprobe(void)
+{
+	need_reprobe = 1;
+	queue_work(ccw_device_work, &css_reprobe_work);
+}
+
+EXPORT_SYMBOL_GPL(css_schedule_reprobe);
+
 /*
  * Rescan for new devices. FIXME: This is slow.
  * This function is called when we have lost CRWs due to overflows and we have
@@ -542,9 +623,13 @@ init_channel_subsystem (void)
 		ret = device_register(&css[i]->device);
 		if (ret)
 			goto out_free;
-		if (css_characteristics_avail && css_chsc_characteristics.secm)
-			device_create_file(&css[i]->device,
-					   &dev_attr_cm_enable);
+		if (css_characteristics_avail &&
+		    css_chsc_characteristics.secm) {
+			ret = device_create_file(&css[i]->device,
+						 &dev_attr_cm_enable);
+			if (ret)
+				goto out_device;
+		}
 	}
 	css_init_done = 1;
 
@@ -552,6 +637,8 @@ init_channel_subsystem (void)
 
 	for_each_subchannel(__init_channel_subsystem, NULL);
 	return 0;
+out_device:
+	device_unregister(&css[i]->device);
 out_free:
 	kfree(css[i]);
 out_unregister: