[PATCH 4.20 336/352] scsi: sd_zbc: Fix zone information messages

[Greg Kroah-Hartman]

4.20-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Damien Le Moal <damien.lemoal@xxxxxxx>

commit 88fc41c407158a7d2eaa4b2f7cfa289749d456c6 upstream.

Commit bf5054569653 ("block: Introduce blk_revalidate_disk_zones()")
inadvertently broke the message output of sd_zbc_print_zones() because the
zone information initialization of the scsi disk structure was moved to the
second scan run while sd_zbc_print_zones() is called on the first
scan. This leads to the following incorrect message to be printed for any
ZBC or ZAC zoned disks.

"...[sdX] 4294967295 zones of 0 logical blocks + 1 runt zone"

Fix this by initializing sdkp zone size and number of zones early on the
first scan. This does not impact the execution of
blk_revalidate_zones(). This functions is still called only once the block
device capacity is set on the second revalidate run on boot, or if the disk
zone configuration changed (i.e. the disk changed).

Fixes: bf5054569653 ("block: Introduce blk_revalidate_disk_zones()")
Cc: stable@xxxxxxxxxxxxxxx
Signed-off-by: Damien Le Moal <damien.lemoal@xxxxxxx>
Signed-off-by: Martin K. Petersen <martin.petersen@xxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
 drivers/scsi/sd_zbc.c |   12 ++++++++----
 1 file changed, 8 insertions(+), 4 deletions(-)

--- a/drivers/scsi/sd_zbc.c
+++ b/drivers/scsi/sd_zbc.c
@@ -462,12 +462,16 @@ int sd_zbc_read_zones(struct scsi_disk *
 	sdkp->device->use_10_for_rw = 0;
 
 	/*
-	 * If something changed, revalidate the disk zone bitmaps once we have
-	 * the capacity, that is on the second revalidate execution during disk
-	 * scan and always during normal revalidate.
+	 * Revalidate the disk zone bitmaps once the block device capacity is
+	 * set on the second revalidate execution during disk scan and if
+	 * something changed when executing a normal revalidate.
 	 */
-	if (sdkp->first_scan)
+	if (sdkp->first_scan) {
+		sdkp->zone_blocks = zone_blocks;
+		sdkp->nr_zones = nr_zones;
 		return 0;
+	}
+
 	if (sdkp->zone_blocks != zone_blocks ||
 	    sdkp->nr_zones != nr_zones ||
 	    disk->queue->nr_zones != nr_zones) {