nvmet: use NVME_NS_FEAT_OPTPERF_SHIFT

Use the NVME_NS_FEAT_OPTPERF_SHIFT constant in nvmet_bdev_set_limits()
to set the OPTPERF bits of the nvme_id_ns NSFEAT field instead of the
magic number 4.

Signed-off-by: Caleb Sander Mateos <[email protected]>
Reviewed-by: Christoph Hellwig <[email protected]>
Signed-off-by: Keith Busch <[email protected]>

Author: calebsander

drivers/nvme/target/io-cmd-bdev.c

@@ -30,11 +30,11 @@ void nvmet_bdev_set_limits(struct block_device *bdev, struct nvme_id_ns *id)
 	id->nacwu = lpp0b;
 
 	/*
-	 * Bit 4 indicates that the fields NPWG, NPWA, NPDG, NPDA, and
+	 * OPTPERF = 01b indicates that the fields NPWG, NPWA, NPDG, NPDA, and
 	 * NOWS are defined for this namespace and should be used by
 	 * the host for I/O optimization.
 	 */
-	id->nsfeat |= 1 << 4;
+	id->nsfeat |= 0x1 << NVME_NS_FEAT_OPTPERF_SHIFT;
 	/* NPWG = Namespace Preferred Write Granularity. 0's based */
 	id->npwg = to0based(bdev_io_min(bdev) / bdev_logical_block_size(bdev));
 	/* NPWA = Namespace Preferred Write Alignment. 0's based */