block: don't look at the struct device dev_t in disk_devt

The hidden gendisks introduced in the next patch need to keep the dev field in their struct device empty so that udev won't try to create block device nodes for them. To support that rewrite disk_devt to look at the major and first_minor fields in the gendisk itself instead of looking into the struct device. Signed-off-by: Christoph Hellwig <[email protected]> Reviewed-by: Johannes Thumshirn <[email protected]> Reviewed-by: Hannes Reinecke <[email protected]> Signed-off-by: Jens Axboe <[email protected]>
kyagi · Nov 3, 2017 · 517bf3c · 517bf3c
1 parent ef71de8
commit 517bf3c
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Showing 2 changed files with 1 addition and 5 deletions.
diff --git a/block/genhd.c b/block/genhd.c
@@ -649,10 +649,6 @@ void device_add_disk(struct device *parent, struct gendisk *disk)
 		return;
 	}
 	disk_to_dev(disk)->devt = devt;
-
-	/* ->major and ->first_minor aren't supposed to be
-	 * dereferenced from here on, but set them just in case.
-	 */
 	disk->major = MAJOR(devt);
 	disk->first_minor = MINOR(devt);
 

diff --git a/include/linux/genhd.h b/include/linux/genhd.h
@@ -234,7 +234,7 @@ static inline bool disk_part_scan_enabled(struct gendisk *disk)
 
 static inline dev_t disk_devt(struct gendisk *disk)
 {
-	return disk_to_dev(disk)->devt;
+	return MKDEV(disk->major, disk->first_minor);
 }
 
 static inline dev_t part_devt(struct hd_struct *part)