Re: [PATCH v2 1/2] nvmet: expose IEEE OUI to configfs

[Sagi Grimberg <sagi@grimberg.me>]

> Allow user to set OUI for the controller vendor.
> 
> Reviewed-by: Konstantin Shelekhin <k.shelekhin@yadro.com>
> Reviewed-by: Dmitriy Bogdanov <d.bogdanov@yadro.com>
> Signed-off-by: Aleksandr Miloserdov <a.miloserdov@yadro.com>
> ---
>   drivers/nvme/target/admin-cmd.c |  7 ++---
>   drivers/nvme/target/configfs.c  | 49 +++++++++++++++++++++++++++++++++
>   drivers/nvme/target/core.c      |  2 ++
>   drivers/nvme/target/nvmet.h     |  1 +
>   4 files changed, 54 insertions(+), 5 deletions(-)
> 
> diff --git a/drivers/nvme/target/admin-cmd.c b/drivers/nvme/target/admin-cmd.c
> index c8a061ce3ee5..48a2f587f38a 100644
> --- a/drivers/nvme/target/admin-cmd.c
> +++ b/drivers/nvme/target/admin-cmd.c
> @@ -372,6 +372,8 @@ static void nvmet_execute_identify_ctrl(struct nvmet_req *req)
>   	memcpy_and_pad(id->fr, sizeof(id->fr),
>   		       UTS_RELEASE, strlen(UTS_RELEASE), ' ');
>   
> +	put_unaligned_le24(subsys->ieee_oui, id->ieee);
> +

Any particular reason why it is placed here and not where the comment
was?

>   	id->rab = 6;
>   
>   	if (nvmet_is_disc_subsys(ctrl->subsys))
> @@ -379,11 +381,6 @@ static void nvmet_execute_identify_ctrl(struct nvmet_req *req)
>   	else
>   		id->cntrltype = NVME_CTRL_IO;
>   
> -	/*
> -	 * XXX: figure out how we can assign a IEEE OUI, but until then
> -	 * the safest is to leave it as zeroes.
> -	 */
> -
>   	/* we support multiple ports, multiples hosts and ANA: */
>   	id->cmic = NVME_CTRL_CMIC_MULTI_PORT | NVME_CTRL_CMIC_MULTI_CTRL |
>   		NVME_CTRL_CMIC_ANA;
> diff --git a/drivers/nvme/target/configfs.c b/drivers/nvme/target/configfs.c
> index 89242b0f8614..ad62e36ec997 100644
> --- a/drivers/nvme/target/configfs.c
> +++ b/drivers/nvme/target/configfs.c
> @@ -1265,6 +1265,54 @@ static ssize_t nvmet_subsys_attr_model_store(struct config_item *item,
>   }
>   CONFIGFS_ATTR(nvmet_subsys_, attr_model);
>   
> +static ssize_t nvmet_subsys_attr_ieee_oui_show(struct config_item *item,
> +					    char *page)
> +{
> +	struct nvmet_subsys *subsys = to_subsys(item);
> +
> +	return sysfs_emit(page, "0x%06x\n", subsys->ieee_oui);
> +}
> +
> +static ssize_t nvmet_subsys_attr_ieee_oui_store_locked(struct nvmet_subsys *subsys,
> +		const char *page, size_t count)
> +{
> +	uint32_t val = 0;
> +	int ret;
> +
> +	if (subsys->subsys_discovered) {
> +		pr_err("Can't set IEEE OUI. 0x%06x is already assigned\n",
> +		      subsys->ieee_oui);
> +		return -EINVAL;
> +	}
> +
> +	ret = kstrtou32(page, 0, &val);
> +	if (ret < 0)
> +		return ret;
> +
> +	if (val >= 0x1000000)
> +		return -EINVAL;
> +
> +	subsys->ieee_oui = val;
> +
> +	return count;
> +}
> +
> +static ssize_t nvmet_subsys_attr_ieee_oui_store(struct config_item *item,
> +					     const char *page, size_t count)
> +{
> +	struct nvmet_subsys *subsys = to_subsys(item);
> +	ssize_t ret;
> +
> +	down_write(&nvmet_config_sem);
> +	mutex_lock(&subsys->lock);
> +	ret = nvmet_subsys_attr_ieee_oui_store_locked(subsys, page, count);
> +	mutex_unlock(&subsys->lock);
> +	up_write(&nvmet_config_sem);
> +
> +	return ret;
> +}
> +CONFIGFS_ATTR(nvmet_subsys_, attr_ieee_oui);
> +
>   #ifdef CONFIG_BLK_DEV_INTEGRITY
>   static ssize_t nvmet_subsys_attr_pi_enable_show(struct config_item *item,
>   						char *page)
> @@ -1323,6 +1371,7 @@ static struct configfs_attribute *nvmet_subsys_attrs[] = {
>   	&nvmet_subsys_attr_attr_cntlid_max,
>   	&nvmet_subsys_attr_attr_model,
>   	&nvmet_subsys_attr_attr_qid_max,
> +	&nvmet_subsys_attr_attr_ieee_oui,
>   #ifdef CONFIG_BLK_DEV_INTEGRITY
>   	&nvmet_subsys_attr_attr_pi_enable,
>   #endif
> diff --git a/drivers/nvme/target/core.c b/drivers/nvme/target/core.c
> index aecb5853f8da..ec697ceeac56 100644
> --- a/drivers/nvme/target/core.c
> +++ b/drivers/nvme/target/core.c
> @@ -1561,6 +1561,8 @@ struct nvmet_subsys *nvmet_subsys_alloc(const char *subsysnqn,
>   		goto free_subsys;
>   	}
>   
> +	subsys->ieee_oui = 0;
> +
>   	switch (type) {
>   	case NVME_NQN_NVME:
>   		subsys->max_qid = NVMET_NR_QUEUES;
> diff --git a/drivers/nvme/target/nvmet.h b/drivers/nvme/target/nvmet.h
> index dfe3894205aa..1dc0ff8b2f3f 100644
> --- a/drivers/nvme/target/nvmet.h
> +++ b/drivers/nvme/target/nvmet.h
> @@ -264,6 +264,7 @@ struct nvmet_subsys {
>   	struct config_group	allowed_hosts_group;
>   
>   	char			*model_number;
> +	u32			ieee_oui;
>   
>   #ifdef CONFIG_NVME_TARGET_PASSTHRU
>   	struct nvme_ctrl	*passthru_ctrl;