nvme: read the subsystem NQN from Identify Controller
NVMe 1.2.1 or later requires controllers to provide a subsystem NQN in the
Identify controller data structures. Use this NQN for the subsysnqn
sysfs attribute by storing it in the nvme_ctrl structure after verifying
it. For older controllers we generate a "fake" NQN per non-normative
text in the NVMe 1.3 spec.
Signed-off-by: Christoph Hellwig <hch@lst.de>
Reviewed-by: Keith Busch <keith.busch@intel.com>
Reviewed-by: Johannes Thumshirn <jthumshirn@suse.de>
Signed-off-by: Sagi Grimberg <sagi@grimberg.me>
Signed-off-by: Jens Axboe <axboe@kernel.dk>
diff --git a/drivers/nvme/host/core.c b/drivers/nvme/host/core.c
index 9c03655..3593abf 100644
--- a/drivers/nvme/host/core.c
+++ b/drivers/nvme/host/core.c
@@ -1705,6 +1705,31 @@ static bool quirk_matches(const struct nvme_id_ctrl *id,
string_matches(id->fr, q->fr, sizeof(id->fr));
}
+static void nvme_init_subnqn(struct nvme_ctrl *ctrl, struct nvme_id_ctrl *id)
+{
+ size_t nqnlen;
+ int off;
+
+ nqnlen = strnlen(id->subnqn, NVMF_NQN_SIZE);
+ if (nqnlen > 0 && nqnlen < NVMF_NQN_SIZE) {
+ strcpy(ctrl->subnqn, id->subnqn);
+ return;
+ }
+
+ if (ctrl->vs >= NVME_VS(1, 2, 1))
+ dev_warn(ctrl->device, "missing or invalid SUBNQN field.\n");
+
+ /* Generate a "fake" NQN per Figure 254 in NVMe 1.3 + ECN 001 */
+ off = snprintf(ctrl->subnqn, NVMF_NQN_SIZE,
+ "nqn.2014.08.org.nvmexpress:%4x%4x",
+ le16_to_cpu(id->vid), le16_to_cpu(id->ssvid));
+ memcpy(ctrl->subnqn + off, id->sn, sizeof(id->sn));
+ off += sizeof(id->sn);
+ memcpy(ctrl->subnqn + off, id->mn, sizeof(id->mn));
+ off += sizeof(id->mn);
+ memset(ctrl->subnqn + off, 0, sizeof(ctrl->subnqn) - off);
+}
+
/*
* Initialize the cached copies of the Identify data and various controller
* register in our nvme_ctrl structure. This should be called as soon as
@@ -1740,6 +1765,8 @@ int nvme_init_identify(struct nvme_ctrl *ctrl)
return -EIO;
}
+ nvme_init_subnqn(ctrl, id);
+
if (!ctrl->identified) {
/*
* Check for quirks. Quirk can depend on firmware version,
@@ -2135,8 +2162,7 @@ static ssize_t nvme_sysfs_show_subsysnqn(struct device *dev,
{
struct nvme_ctrl *ctrl = dev_get_drvdata(dev);
- return snprintf(buf, PAGE_SIZE, "%s\n",
- ctrl->ops->get_subsysnqn(ctrl));
+ return snprintf(buf, PAGE_SIZE, "%s\n", ctrl->subnqn);
}
static DEVICE_ATTR(subsysnqn, S_IRUGO, nvme_sysfs_show_subsysnqn, NULL);
@@ -2181,7 +2207,6 @@ static umode_t nvme_dev_attrs_are_visible(struct kobject *kobj,
return 0;
}
- CHECK_ATTR(ctrl, a, subsysnqn);
CHECK_ATTR(ctrl, a, address);
return a->mode;
