cciss: Add usage_count attribute to each logical drive in /sys
[linux-2.6.git] / drivers / block / cciss.c
index 063e8b0..b808e92 100644 (file)
@@ -626,6 +626,25 @@ static ssize_t cciss_show_raid_level(struct device *dev,
 }
 DEVICE_ATTR(raid_level, S_IRUGO, cciss_show_raid_level, NULL);
 
+static ssize_t cciss_show_usage_count(struct device *dev,
+                                     struct device_attribute *attr, char *buf)
+{
+       drive_info_struct *drv = dev_get_drvdata(dev);
+       struct ctlr_info *h = to_hba(drv->dev->parent);
+       unsigned long flags;
+       int count;
+
+       spin_lock_irqsave(CCISS_LOCK(h->ctlr), flags);
+       if (h->busy_configuring) {
+               spin_unlock_irqrestore(CCISS_LOCK(h->ctlr), flags);
+               return -EBUSY;
+       }
+       count = drv->usage_count;
+       spin_unlock_irqrestore(CCISS_LOCK(h->ctlr), flags);
+       return snprintf(buf, 20, "%d\n", count);
+}
+DEVICE_ATTR(usage_count, S_IRUGO, cciss_show_usage_count, NULL);
+
 static struct attribute *cciss_host_attrs[] = {
        &dev_attr_rescan.attr,
        NULL
@@ -653,6 +672,7 @@ static struct attribute *cciss_dev_attrs[] = {
        &dev_attr_rev.attr,
        &dev_attr_lunid.attr,
        &dev_attr_raid_level.attr,
+       &dev_attr_usage_count.attr,
        NULL
 };