[PATCH v5 06/16] nvme: Rapid Path Failure Recovery read controller identify fields

TP8028 Rapid Path Failure added new fields to controller identify
response. Read CIU (Controller Instance Uniquifier), CIRN (Controller
Instance Random Number), and CCRL (Cross-Controller Reset Limit) from
controller identify response. Expose CIU and CIRN as sysfs attributes
so the values can be used directly by user if needed.

Also add the nvme_fence_timeout_ms() helper that derives a fencing
timeout from the controller keep-alive timeout (kato).

Signed-off-by: Mohamed Khalfella <[email protected]>
Reviewed-by: Hannes Reinecke <[email protected]>
Reviewed-by: Sagi Grimberg <[email protected]>
---
 drivers/nvme/host/core.c  |  4 ++++
 drivers/nvme/host/nvme.h  | 10 ++++++++++
 drivers/nvme/host/sysfs.c | 23 +++++++++++++++++++++++
 3 files changed, 37 insertions(+)

diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index db0c8ad4628a..203ecafc1aec 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -3643,6 +3643,10 @@ static int nvme_init_identify(struct nvme_ctrl *ctrl)
 	ctrl->crdt[1] = le16_to_cpu(id->crdt2);
 	ctrl->crdt[2] = le16_to_cpu(id->crdt3);
 
+	ctrl->ciu = id->ciu;
+	ctrl->cirn = le64_to_cpu(id->cirn);
+	ctrl->ccrl = id->ccrl;
+
 	ctrl->oacs = le16_to_cpu(id->oacs);
 	ctrl->oncs = le16_to_cpu(id->oncs);
 	ctrl->mtfa = le16_to_cpu(id->mtfa);
diff --git a/drivers/nvme/host/nvme.h b/drivers/nvme/host/nvme.h
index a679a4c61462..9b071076c9f4 100644
--- a/drivers/nvme/host/nvme.h
+++ b/drivers/nvme/host/nvme.h
@@ -384,11 +384,14 @@ struct nvme_ctrl {
 	u16 crdt[3];
 	u16 oncs;
 	u8 dmrl;
+	u8 ciu;
 	u32 dmrsl;
+	u64 cirn;
 	u16 oacs;
 	u16 sqsize;
 	u32 max_namespaces;
 	atomic_t abort_limit;
+	u8 ccrl;
 	u8 vwc;
 	u32 vs;
 	u32 sgls;
@@ -1313,4 +1316,11 @@ static inline bool nvme_multi_css(struct nvme_ctrl *ctrl)
 	return (ctrl->ctrl_config & NVME_CC_CSS_MASK) == NVME_CC_CSS_CSI;
 }
 
+static inline unsigned long nvme_fence_timeout_ms(struct nvme_ctrl *ctrl)
+{
+	if (ctrl->ctratt & NVME_CTRL_ATTR_TBKAS)
+		return 3 * ctrl->kato * 1000;
+	return 2 * ctrl->kato * 1000;
+}
+
 #endif /* _NVME_H */
diff --git a/drivers/nvme/host/sysfs.c b/drivers/nvme/host/sysfs.c
index abf8edaae371..dd48c0989301 100644
--- a/drivers/nvme/host/sysfs.c
+++ b/drivers/nvme/host/sysfs.c
@@ -487,6 +487,27 @@ nvme_show_int_function(queue_count);
 nvme_show_int_function(sqsize);
 nvme_show_int_function(kato);
 
+static ssize_t nvme_sysfs_ciu_show(struct device *dev,
+					  struct device_attribute *attr,
+					  char *buf)
+{
+	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%02x\n", ctrl->ciu);
+}
+static DEVICE_ATTR(ciu, S_IRUSR, nvme_sysfs_ciu_show, NULL);
+
+static ssize_t nvme_sysfs_cirn_show(struct device *dev,
+					  struct device_attribute *attr,
+					  char *buf)
+{
+	struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
+
+	return sysfs_emit(buf, "%016llx\n", ctrl->cirn);
+}
+static DEVICE_ATTR(cirn, S_IRUSR, nvme_sysfs_cirn_show, NULL);
+
+
 static ssize_t nvme_sysfs_delete(struct device *dev,
 				struct device_attribute *attr, const char *buf,
 				size_t count)
@@ -941,6 +962,8 @@ static struct attribute *nvme_dev_attrs[] = {
 	&dev_attr_numa_node.attr,
 	&dev_attr_queue_count.attr,
 	&dev_attr_sqsize.attr,
+	&dev_attr_ciu.attr,
+	&dev_attr_cirn.attr,
 	&dev_attr_hostnqn.attr,
 	&dev_attr_hostid.attr,
 	&dev_attr_ctrl_loss_tmo.attr,
-- 
2.54.0