ANDROID: Block: add OEM data to struct gendisk

In order to alleviate the issue of priority inversion caused by the lock_page,
it is proposed to add oem_data to the struct gendisk to store a pointer to
its struct block_device . This will allow us to check its priority through a
customized scheduler hook when lock_folio.

Bug: 338959088
Bug: 407947260

Change-Id: I118ef11cb89a3fad9a15a2c3b8383d42be0fded4
Signed-off-by: Wang Jianzheng <11134417@vivo.corp-partner.google.com>
(cherry picked from commit feb92ccf10bce90739b5f51cc33d1bd6f16d7fab)
Signed-off-by: ying zuxin <11154159@vivo.com>

include/linux/blkdev.h

@@ -219,6 +219,8 @@ struct gendisk {
 	 * devices that do not have multiple independent access ranges.
 	 */
 	struct blk_independent_access_ranges *ia_ranges;
+
+	ANDROID_OEM_DATA(1);
 };
 
 /**