block: remove queue_discard_alignment

Just use bdev_alignment_offset in disk_discard_alignment_show instead.
That helpers is the same except for an always false branch that doesn't
matter in this slow path.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20220415045258.199825-20-hch@lst.deSigned-off-by: Jens Axboe <axboe@kernel.dk>

block/genhd.c

@@ -1019,7 +1019,7 @@ static ssize_t disk_discard_alignment_show(struct device *dev,
 {
 	struct gendisk *disk = dev_to_disk(dev);
 
-	return sprintf(buf, "%d\n", queue_discard_alignment(disk->queue));
+	return sprintf(buf, "%d\n", bdev_alignment_offset(disk->part0));
 }
 
 static ssize_t diskseq_show(struct device *dev,

include/linux/blkdev.h

@@ -1253,14 +1253,6 @@ bdev_zone_write_granularity(struct block_device *bdev)
 
 int bdev_alignment_offset(struct block_device *bdev);
 
-static inline int queue_discard_alignment(const struct request_queue *q)
-{
-	if (q->limits.discard_misaligned)
-		return -1;
-
-	return q->limits.discard_alignment;
-}
-
 static inline int queue_limit_discard_alignment(struct queue_limits *lim, sector_t sector)
 {
 	unsigned int alignment, granularity, offset;