block: introduce GENHD_FL_HIDDEN
With this flag a driver can create a gendisk that can be used for I/O
submission inside the kernel, but which is not registered as user
facing block device. This will be useful for the NVMe multipath
implementation.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/include/linux/genhd.h b/include/linux/genhd.h
index 5c0ed5d..93aae34 100644
--- a/include/linux/genhd.h
+++ b/include/linux/genhd.h
@@ -140,6 +140,7 @@ struct hd_struct {
#define GENHD_FL_NATIVE_CAPACITY 128
#define GENHD_FL_BLOCK_EVENTS_ON_EXCL_WRITE 256
#define GENHD_FL_NO_PART_SCAN 512
+#define GENHD_FL_HIDDEN 1024
enum {
DISK_EVENT_MEDIA_CHANGE = 1 << 0, /* media changed */