block: Introduce BLKGETZONESZ ioctl

damien-lemoal · axboe · commit 72cd87576d1d · 2018-10-25T11:17:40.000-06:00
Get a zoned block device zone size in number of 512 B sectors.
The zone size is always 0 for regular block devices.

Reviewed-by: Hannes Reinecke &lt;hare@suse.com&gt;
Reviewed-by: Christoph Hellwig &lt;hch@lst.de&gt;
Signed-off-by: Damien Le Moal &lt;damien.lemoal@wdc.com&gt;
Signed-off-by: Jens Axboe &lt;axboe@kernel.dk&gt;
diff --git a/block/ioctl.c b/block/ioctl.c
@@ -532,6 +532,8 @@ int blkdev_ioctl(struct block_device *bdev, fmode_t mode, unsigned cmd,
 		return blkdev_report_zones_ioctl(bdev, mode, cmd, arg);
 	case BLKRESETZONE:
 		return blkdev_reset_zones_ioctl(bdev, mode, cmd, arg);
+	case BLKGETZONESZ:
+		return put_uint(arg, bdev_zone_sectors(bdev));
 	case HDIO_GETGEO:
 		return blkdev_getgeo(bdev, argp);
 	case BLKRAGET:
diff --git a/include/uapi/linux/blkzoned.h b/include/uapi/linux/blkzoned.h
@@ -137,8 +137,10 @@ struct blk_zone_range {
  *                 sector specified in the report request structure.
  * @BLKRESETZONE: Reset the write pointer of the zones in the specified
  *                sector range. The sector range must be zone aligned.
+ * @BLKGETZONESZ: Get the device zone size in number of 512 B sectors.
  */
 #define BLKREPORTZONE	_IOWR(0x12, 130, struct blk_zone_report)
 #define BLKRESETZONE	_IOW(0x12, 131, struct blk_zone_range)
+#define BLKGETZONESZ	_IOW(0x12, 132, __u32)
 
 #endif /* _UAPI_BLKZONED_H */
