From e5fd91f1ef340da553f7a79da9540c3db711c937 Mon Sep 17 00:00:00 2001
From: André Fabian Silva Delgado <emulatorman@parabola.nu>
Date: Tue, 8 Sep 2015 01:01:14 -0300
Subject: Linux-libre 4.2-gnu

---
 drivers/s390/block/dasd.c       | 53 +++++++++++++++++++++++++++++++++++------
 drivers/s390/block/dasd_alias.c |  3 ++-
 drivers/s390/block/dasd_genhd.c | 19 ++++-----------
 3 files changed, 53 insertions(+), 22 deletions(-)

(limited to 'drivers/s390/block')

diff --git a/drivers/s390/block/dasd.c b/drivers/s390/block/dasd.c
index 57fd66357..f73d2f579 100644
--- a/drivers/s390/block/dasd.c
+++ b/drivers/s390/block/dasd.c
@@ -38,6 +38,8 @@
  */
 #define DASD_CHANQ_MAX_SIZE 4
 
+#define DASD_DIAG_MOD		"dasd_diag_mod"
+
 /*
  * SECTION: exported variables of dasd.c
  */
@@ -1860,6 +1862,33 @@ static void __dasd_device_check_expire(struct dasd_device *device)
 	}
 }
 
+/*
+ * return 1 when device is not eligible for IO
+ */
+static int __dasd_device_is_unusable(struct dasd_device *device,
+				     struct dasd_ccw_req *cqr)
+{
+	int mask = ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM);
+
+	if (test_bit(DASD_FLAG_OFFLINE, &device->flags)) {
+		/* dasd is being set offline. */
+		return 1;
+	}
+	if (device->stopped) {
+		if (device->stopped & mask) {
+			/* stopped and CQR will not change that. */
+			return 1;
+		}
+		if (!test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags)) {
+			/* CQR is not able to change device to
+			 * operational. */
+			return 1;
+		}
+		/* CQR required to get device operational. */
+	}
+	return 0;
+}
+
 /*
  * Take a look at the first request on the ccw queue and check
  * if it needs to be started.
@@ -1874,13 +1903,8 @@ static void __dasd_device_start_head(struct dasd_device *device)
 	cqr = list_entry(device->ccw_queue.next, struct dasd_ccw_req, devlist);
 	if (cqr->status != DASD_CQR_QUEUED)
 		return;
-	/* when device is stopped, return request to previous layer
-	 * exception: only the disconnect or unresumed bits are set and the
-	 * cqr is a path verification request
-	 */
-	if (device->stopped &&
-	    !(!(device->stopped & ~(DASD_STOPPED_DC_WAIT | DASD_UNRESUMED_PM))
-	      && test_bit(DASD_CQR_VERIFY_PATH, &cqr->flags))) {
+	/* if device is not usable return request to upper layer */
+	if (__dasd_device_is_unusable(device, cqr)) {
 		cqr->intrc = -EAGAIN;
 		cqr->status = DASD_CQR_CLEARED;
 		dasd_schedule_device_bh(device);
@@ -3300,6 +3324,21 @@ int dasd_generic_set_online(struct ccw_device *cdev,
 	discipline = base_discipline;
 	if (device->features & DASD_FEATURE_USEDIAG) {
 	  	if (!dasd_diag_discipline_pointer) {
+			/* Try to load the required module. */
+			rc = request_module(DASD_DIAG_MOD);
+			if (rc) {
+				pr_warn("%s Setting the DASD online failed "
+					"because the required module %s "
+					"could not be loaded (rc=%d)\n",
+					dev_name(&cdev->dev), DASD_DIAG_MOD,
+					rc);
+				dasd_delete_device(device);
+				return -ENODEV;
+			}
+		}
+		/* Module init could have failed, so check again here after
+		 * request_module(). */
+		if (!dasd_diag_discipline_pointer) {
 			pr_warn("%s Setting the DASD online failed because of missing DIAG discipline\n",
 				dev_name(&cdev->dev));
 			dasd_delete_device(device);
diff --git a/drivers/s390/block/dasd_alias.c b/drivers/s390/block/dasd_alias.c
index a2597e683..ee3a6faae 100644
--- a/drivers/s390/block/dasd_alias.c
+++ b/drivers/s390/block/dasd_alias.c
@@ -699,7 +699,8 @@ struct dasd_device *dasd_alias_get_start_dev(struct dasd_device *base_device)
 					       struct dasd_device, alias_list);
 	spin_unlock_irqrestore(&lcu->lock, flags);
 	alias_priv = (struct dasd_eckd_private *) alias_device->private;
-	if ((alias_priv->count < private->count) && !alias_device->stopped)
+	if ((alias_priv->count < private->count) && !alias_device->stopped &&
+	    !test_bit(DASD_FLAG_OFFLINE, &alias_device->flags))
 		return alias_device;
 	else
 		return NULL;
diff --git a/drivers/s390/block/dasd_genhd.c b/drivers/s390/block/dasd_genhd.c
index 90f39f79f..ef1d9fb06 100644
--- a/drivers/s390/block/dasd_genhd.c
+++ b/drivers/s390/block/dasd_genhd.c
@@ -99,9 +99,8 @@ void dasd_gendisk_free(struct dasd_block *block)
 int dasd_scan_partitions(struct dasd_block *block)
 {
 	struct block_device *bdev;
-	int retry, rc;
+	int rc;
 
-	retry = 5;
 	bdev = bdget_disk(block->gdp, 0);
 	if (!bdev) {
 		DBF_DEV_EVENT(DBF_ERR, block->base, "%s",
@@ -116,19 +115,11 @@ int dasd_scan_partitions(struct dasd_block *block)
 			      rc);
 		return -ENODEV;
 	}
-	/*
-	 * See fs/partition/check.c:register_disk,rescan_partitions
-	 * Can't call rescan_partitions directly. Use ioctl.
-	 */
-	rc = ioctl_by_bdev(bdev, BLKRRPART, 0);
-	while (rc == -EBUSY && retry > 0) {
-		schedule();
-		rc = ioctl_by_bdev(bdev, BLKRRPART, 0);
-		retry--;
+
+	rc = blkdev_reread_part(bdev);
+	if (rc)
 		DBF_DEV_EVENT(DBF_ERR, block->base,
-			      "scan partitions error, retry %d rc %d",
-			      retry, rc);
-	}
+				"scan partitions error, rc %d", rc);
 
 	/*
 	 * Since the matching blkdev_put call to the blkdev_get in
-- 
cgit v1.2.3-54-g00ecf