s390/dasd: retry partition detection
In case somebody attempted to open the device during online
processing the partition detection ioctl may have failed.
Added a retry loop to avoid not detected partitions.
Signed-off-by: Stefan Haberland <stefan.haberland@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
diff --git a/drivers/s390/block/dasd_genhd.c b/drivers/s390/block/dasd_genhd.c
index f224d59..90f39f7 100644
--- a/drivers/s390/block/dasd_genhd.c
+++ b/drivers/s390/block/dasd_genhd.c
@@ -99,15 +99,37 @@
int dasd_scan_partitions(struct dasd_block *block)
{
struct block_device *bdev;
+ int retry, rc;
+ retry = 5;
bdev = bdget_disk(block->gdp, 0);
- if (!bdev || blkdev_get(bdev, FMODE_READ, NULL) < 0)
+ if (!bdev) {
+ DBF_DEV_EVENT(DBF_ERR, block->base, "%s",
+ "scan partitions error, bdget returned NULL");
return -ENODEV;
+ }
+
+ rc = blkdev_get(bdev, FMODE_READ, NULL);
+ if (rc < 0) {
+ DBF_DEV_EVENT(DBF_ERR, block->base,
+ "scan partitions error, blkdev_get returned %d",
+ rc);
+ return -ENODEV;
+ }
/*
* See fs/partition/check.c:register_disk,rescan_partitions
* Can't call rescan_partitions directly. Use ioctl.
*/
- ioctl_by_bdev(bdev, BLKRRPART, 0);
+ rc = ioctl_by_bdev(bdev, BLKRRPART, 0);
+ while (rc == -EBUSY && retry > 0) {
+ schedule();
+ rc = ioctl_by_bdev(bdev, BLKRRPART, 0);
+ retry--;
+ DBF_DEV_EVENT(DBF_ERR, block->base,
+ "scan partitions error, retry %d rc %d",
+ retry, rc);
+ }
+
/*
* Since the matching blkdev_put call to the blkdev_get in
* this function is not called before dasd_destroy_partitions