[PATCH 2/2] nvme: fix atomic write boundary validation

[Christoph Hellwig <hch@lst.de>]

Don't mix the namespace and controller values, and validate the
per-controller limit when probing the controller.  This avoid spurious
failures for controllers with namespaces that have different namespaces
with different logical block sizes, or report the per-namespace values
only for some namespaces.

It also fixes a missing queue_limits_cancel_update in an error path by
removing that error path.

Fixes: 8695f060a029 ("nvme: all namespaces in a subsystem must adhere to a common atomic write size")
Reported-by: Yi Zhang <yi.zhang@redhat.com>
Signed-off-by: Christoph Hellwig <hch@lst.de>
---
 drivers/nvme/host/core.c | 34 ++++++++++++----------------------
 drivers/nvme/host/nvme.h |  3 +--
 2 files changed, 13 insertions(+), 24 deletions(-)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 520fb5f1e214..3da5ac71a9b0 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -2041,17 +2041,7 @@ static u32 nvme_configure_atomic_write(struct nvme_ns *ns,
 		 * no clear language in the specification prohibiting different
 		 * values for different controllers in the subsystem.
 		 */
-		atomic_bs = (1 + ns->ctrl->awupf) * bs;
-	}
-
-	if (!ns->ctrl->subsys->atomic_bs) {
-		ns->ctrl->subsys->atomic_bs = atomic_bs;
-	} else if (ns->ctrl->subsys->atomic_bs != atomic_bs) {
-		dev_err_ratelimited(ns->ctrl->device,
-			"%s: Inconsistent Atomic Write Size, Namespace will not be added: Subsystem=%d bytes, Controller/Namespace=%d bytes\n",
-			ns->disk ? ns->disk->disk_name : "?",
-			ns->ctrl->subsys->atomic_bs,
-			atomic_bs);
+		atomic_bs = (1 + ns->ctrl->subsys->awupf) * bs;
 	}
 
 	lim->atomic_write_hw_max = atomic_bs;
@@ -2386,16 +2376,6 @@ static int nvme_update_ns_info_block(struct nvme_ns *ns,
 	if (!nvme_update_disk_info(ns, id, &lim))
 		capacity = 0;
 
-	/*
-	 * Validate the max atomic write size fits within the subsystem's
-	 * atomic write capabilities.
-	 */
-	if (lim.atomic_write_hw_max > ns->ctrl->subsys->atomic_bs) {
-		blk_mq_unfreeze_queue(ns->disk->queue, memflags);
-		ret = -ENXIO;
-		goto out;
-	}
-
 	nvme_config_discard(ns, &lim);
 	if (IS_ENABLED(CONFIG_BLK_DEV_ZONED) &&
 	    ns->head->ids.csi == NVME_CSI_ZNS)
@@ -3555,7 +3535,18 @@ static int nvme_init_identify(struct nvme_ctrl *ctrl)
 		ret = nvme_init_effects(ctrl, id);
 		if (ret)
 			goto out_free;
+
+		ctrl->subsys->awupf = le16_to_cpu(id->awupf);
 	}
+
+	if (le16_to_cpu(id->awupf) != ctrl->subsys->awupf) {
+		dev_err_ratelimited(ctrl->device,
+			"inconsistent AWUPF, controller not added (%u/%u).\n",
+			le16_to_cpu(id->awupf), ctrl->subsys->awupf);
+		ret = -EINVAL;
+		goto out_free;
+	}
+
 	memcpy(ctrl->subsys->firmware_rev, id->fr,
 	       sizeof(ctrl->subsys->firmware_rev));
 
@@ -3651,7 +3642,6 @@ static int nvme_init_identify(struct nvme_ctrl *ctrl)
 		dev_pm_qos_expose_latency_tolerance(ctrl->device);
 	else if (!ctrl->apst_enabled && prev_apst_enabled)
 		dev_pm_qos_hide_latency_tolerance(ctrl->device);
-	ctrl->awupf = le16_to_cpu(id->awupf);
 out_free:
 	kfree(id);
 	return ret;
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index a468cdc5b5cb..7df2ea21851f 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -410,7 +410,6 @@ struct nvme_ctrl {
 
 	enum nvme_ctrl_type cntrltype;
 	enum nvme_dctype dctype;
-	u16 awupf; /* 0's based value. */
 };
 
 static inline enum nvme_ctrl_state nvme_ctrl_state(struct nvme_ctrl *ctrl)
@@ -443,11 +442,11 @@ struct nvme_subsystem {
 	u8			cmic;
 	enum nvme_subsys_type	subtype;
 	u16			vendor_id;
+	u16			awupf; /* 0's based value. */
 	struct ida		ns_ida;
 #ifdef CONFIG_NVME_MULTIPATH
 	enum nvme_iopolicy	iopolicy;
 #endif
-	u32			atomic_bs;
 };
 
 /*
-- 
2.47.2