1 files changed, 49 insertions, 20 deletions

diff --git a/fs/block_dev.c b/fs/block_dev.c
index 9c073dbdc1b0..ee63c2732fa2 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -1403,11 +1403,7 @@ static void flush_disk(struct block_device *bdev, bool kill_dirty)
 		       "resized disk %s\n",
 		       bdev->bd_disk ? bdev->bd_disk->disk_name : "");
 	}
-
-	if (!bdev->bd_disk)
-		return;
-	if (disk_part_scan_enabled(bdev->bd_disk))
-		bdev->bd_invalidated = 1;
+	bdev->bd_invalidated = 1;
 }
 
 /**
@@ -1420,8 +1416,8 @@ static void flush_disk(struct block_device *bdev, bool kill_dirty)
  * and adjusts it if it differs. When shrinking the bdev size, its all caches
  * are freed.
  */
-void check_disk_size_change(struct gendisk *disk, struct block_device *bdev,
-		bool verbose)
+static void check_disk_size_change(struct gendisk *disk,
+		struct block_device *bdev, bool verbose)
 {
 	loff_t disk_size, bdev_size;
 
@@ -1437,6 +1433,7 @@ void check_disk_size_change(struct gendisk *disk, struct block_device *bdev,
 		if (bdev_size > disk_size)
 			flush_disk(bdev, false);
 	}
+	bdev->bd_invalidated = 0;
 }
 
 /**
@@ -1466,7 +1463,6 @@ int revalidate_disk(struct gendisk *disk)
 
 		mutex_lock(&bdev->bd_mutex);
 		check_disk_size_change(disk, bdev, ret == 0);
-		bdev->bd_invalidated = 0;
 		mutex_unlock(&bdev->bd_mutex);
 		bdput(bdev);
 	}
@@ -1512,6 +1508,45 @@ EXPORT_SYMBOL(bd_set_size);
 
 static void __blkdev_put(struct block_device *bdev, fmode_t mode, int for_part);
 
+int bdev_disk_changed(struct block_device *bdev, bool invalidate)
+{
+	struct gendisk *disk = bdev->bd_disk;
+	int ret;
+
+	lockdep_assert_held(&bdev->bd_mutex);
+
+rescan:
+	ret = blk_drop_partitions(disk, bdev);
+	if (ret)
+		return ret;
+
+	if (invalidate)
+		set_capacity(disk, 0);
+	else if (disk->fops->revalidate_disk)
+		disk->fops->revalidate_disk(disk);
+
+	check_disk_size_change(disk, bdev, !invalidate);
+
+	if (get_capacity(disk)) {
+		ret = blk_add_partitions(disk, bdev);
+		if (ret == -EAGAIN)
+			goto rescan;
+	} else {
+		/*
+		 * Tell userspace that the media / partition table may have
+		 * changed.
+		 */
+		kobject_uevent(&disk_to_dev(disk)->kobj, KOBJ_CHANGE);
+	}
+
+	return ret;
+}
+/*
+ * Only exported for for loop and dasd for historic reasons.  Don't use in new
+ * code!
+ */
+EXPORT_SYMBOL_GPL(bdev_disk_changed);
+
 /*
  * bd_mutex locking:
  *
@@ -1594,12 +1629,9 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
 			 * The latter is necessary to prevent ghost
 			 * partitions on a removed medium.
 			 */
-			if (bdev->bd_invalidated) {
-				if (!ret)
-					rescan_partitions(disk, bdev);
-				else if (ret == -ENOMEDIUM)
-					invalidate_partitions(disk, bdev);
-			}
+			if (bdev->bd_invalidated &&
+			    (!ret || ret == -ENOMEDIUM))
+				bdev_disk_changed(bdev, ret == -ENOMEDIUM);
 
 			if (ret)
 				goto out_clear;
@@ -1632,12 +1664,9 @@ static int __blkdev_get(struct block_device *bdev, fmode_t mode, int for_part)
 			if (bdev->bd_disk->fops->open)
 				ret = bdev->bd_disk->fops->open(bdev, mode);
 			/* the same as first opener case, read comment there */
-			if (bdev->bd_invalidated) {
-				if (!ret)
-					rescan_partitions(bdev->bd_disk, bdev);
-				else if (ret == -ENOMEDIUM)
-					invalidate_partitions(bdev->bd_disk, bdev);
-			}
+			if (bdev->bd_invalidated &&
+			    (!ret || ret == -ENOMEDIUM))
+				bdev_disk_changed(bdev, ret == -ENOMEDIUM);
 			if (ret)
 				goto out_unlock_bdev;
 		}