block: make BLK_DEF_MAX_SECTORS unsigned

This is used as an unsigned value, so define it that way to avoid
having to cast it.

Suggested-by: Christoph Hellwig <hch@lst.de>
Signed-off-by: Keith Busch <kbusch@kernel.org>
Reviewed-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Bart Van Assche <bvanassche@acm.org>
Reviewed-by: Martin K. Petersen <martin.petersen@oracle.com>
Link: https://lore.kernel.org/r/20230105205146.3610282-2-kbusch@meta.com
Signed-off-by: Jens Axboe <axboe@kernel.dk>

block/blk-settings.c

@@ -135,7 +135,7 @@ void blk_queue_max_hw_sectors(struct request_queue *q, unsigned int max_hw_secto
 	limits->max_hw_sectors = max_hw_sectors;
 
 	max_sectors = min_not_zero(max_hw_sectors, limits->max_dev_sectors);
-	max_sectors = min_t(unsigned int, max_sectors, BLK_DEF_MAX_SECTORS);
+	max_sectors = min(max_sectors, BLK_DEF_MAX_SECTORS);
 	max_sectors = round_down(max_sectors,
 				 limits->logical_block_size >> SECTOR_SHIFT);
 	limits->max_sectors = max_sectors;

drivers/block/null_blk/main.c

@@ -2123,8 +2123,7 @@ static int null_add_dev(struct nullb_device *dev)
 	blk_queue_physical_block_size(nullb->q, dev->blocksize);
 	if (!dev->max_sectors)
 		dev->max_sectors = queue_max_hw_sectors(nullb->q);
-	dev->max_sectors = min_t(unsigned int, dev->max_sectors,
-				 BLK_DEF_MAX_SECTORS);
+	dev->max_sectors = min(dev->max_sectors, BLK_DEF_MAX_SECTORS);
 	blk_queue_max_hw_sectors(nullb->q, dev->max_sectors);
 
 	if (dev->virt_boundary)

include/linux/blkdev.h

@@ -1095,11 +1095,12 @@ static inline bool bdev_is_partition(struct block_device *bdev)
 enum blk_default_limits {
 	BLK_MAX_SEGMENTS	= 128,
 	BLK_SAFE_MAX_SECTORS	= 255,
-	BLK_DEF_MAX_SECTORS	= 2560,
 	BLK_MAX_SEGMENT_SIZE	= 65536,
 	BLK_SEG_BOUNDARY_MASK	= 0xFFFFFFFFUL,
 };
 
+#define BLK_DEF_MAX_SECTORS 2560u
+
 static inline unsigned long queue_segment_boundary(const struct request_queue *q)
 {
 	return q->limits.seg_boundary_mask;