nvme: update nvme_id_ns OPTPERF constants

In NVMe verson 2.0 and below, OPTPERF comprises only bit 4 of NSFEAT in
the Identify Namespace structure. Since version 2.1, OPTPERF includes
both bits 4 and 5 of NSFEAT. Replace the NVME_NS_FEAT_IO_OPT constant
with NVME_NS_FEAT_OPTPERF_SHIFT, NVME_NS_FEAT_OPTPERF_MASK, and
NVME_NS_FEAT_OPTPERF_MASK_2_1, representing the first bit, pre-2.1 bit
width, and post-2.1 bit width of OPTPERF.

Update nvme_update_disk_info() to check both OPTPERF bits for
controllers that report version 2.1 or newer, as NPWG and NOWS are
supported even if only bit 5 is set.

Signed-off-by: Caleb Sander Mateos <csander@purestorage.com>
Signed-off-by: Keith Busch <kbusch@kernel.org>

Author: calebsander

drivers/nvme/host/core.c

@@ -2066,6 +2066,7 @@ static bool nvme_update_disk_info(struct nvme_ns *ns, struct nvme_id_ns *id,
 	u32 bs = 1U << head->lba_shift;
 	u32 atomic_bs, phys_bs, io_opt = 0;
 	bool valid = true;
+	u8 optperf;
 
 	/*
 	 * The block layer can't support LBA sizes larger than the page size
@@ -2080,7 +2081,12 @@ static bool nvme_update_disk_info(struct nvme_ns *ns, struct nvme_id_ns *id,
 	phys_bs = bs;
 	atomic_bs = nvme_configure_atomic_write(ns, id, lim, bs);
 
-	if (id->nsfeat & NVME_NS_FEAT_IO_OPT) {
+	optperf = id->nsfeat >> NVME_NS_FEAT_OPTPERF_SHIFT;
+	if (ctrl->vs >= NVME_VS(2, 1, 0))
+		optperf &= NVME_NS_FEAT_OPTPERF_MASK_2_1;
+	else
+		optperf &= NVME_NS_FEAT_OPTPERF_MASK;
+	if (optperf) {
 		/* NPWG = Namespace Preferred Write Granularity */
 		phys_bs = bs * (1 + le16_to_cpu(id->npwg));
 		/* NOWS = Namespace Optimal Write Size */

include/linux/nvme.h

@@ -597,7 +597,11 @@ enum {
 enum {
 	NVME_NS_FEAT_THIN	= 1 << 0,
 	NVME_NS_FEAT_ATOMICS	= 1 << 1,
-	NVME_NS_FEAT_IO_OPT	= 1 << 4,
+	NVME_NS_FEAT_OPTPERF_SHIFT = 4,
+	/* In NVMe version 2.0 and below, OPTPERF is only bit 4 of NSFEAT */
+	NVME_NS_FEAT_OPTPERF_MASK = 0x1,
+	/* Since version 2.1, OPTPERF is bits 4 and 5 of NSFEAT */
+	NVME_NS_FEAT_OPTPERF_MASK_2_1 = 0x3,
 	NVME_NS_ATTR_RO		= 1 << 0,
 	NVME_NS_FLBAS_LBA_MASK	= 0xf,
 	NVME_NS_FLBAS_LBA_UMASK	= 0x60,