On 04/19/2018 02:46 AM, xiubli@xxxxxxxxxx wrote:
> From: Xiubo Li <xiubli@xxxxxxxxxx>
>
> For some case we need some module wide configfs to contol some
> attributes of the whole transport module.
When I suggested to move it module wide I just meant to add another mod
param like the global max data area param. I like the approach below
though, because rtslib can work similar to how it does for other
objects. However for tcmu we will have a mix of types, so I am not sure
how you are going to deal with compat. Maybe add a module level attrs
attr and add a max data area there that calls the same mod param code.
There would still be a kernel where it is not supported though.
Add some comments below if we go this route.
>
> Signed-off-by: Xiubo Li <xiubli@xxxxxxxxxx>
> ---
> drivers/target/target_core_configfs.c | 46 +++++++++++++++++++++++++++++++++++
> drivers/target/target_core_hba.c | 11 +++++++++
> drivers/target/target_core_internal.h | 5 ++++
> include/target/target_core_backend.h | 1 +
> 4 files changed, 63 insertions(+)
>
> diff --git a/drivers/target/target_core_configfs.c b/drivers/target/target_core_configfs.c
> index 3f4bf12..a1ee716 100644
> --- a/drivers/target/target_core_configfs.c
> +++ b/drivers/target/target_core_configfs.c
> @@ -79,6 +79,7 @@
> static struct config_group target_core_hbagroup;
> static struct config_group alua_group;
> static struct config_group alua_lu_gps_group;
> +static struct config_group action_group;
>
> static inline struct se_hba *
> item_to_hba(struct config_item *item)
> @@ -1198,6 +1199,7 @@ struct configfs_attribute *passthrough_attrib_attrs[] = {
>
> TB_CIT_SETUP_DRV(dev_attrib, NULL, NULL);
> TB_CIT_SETUP_DRV(dev_action, NULL, NULL);
> +TB_CIT_SETUP_DRV(mod_action, NULL, NULL);
>
> /* End functions for struct config_item_type tb_dev_attrib_cit */
>
> @@ -2893,6 +2895,20 @@ static void target_core_alua_drop_tg_pt_gp(
>
> /* End functions for struct config_item_type target_core_alua_cit */
>
> +/* Start functions for struct config_item_type target_core_action_cit */
> +
> +/*
> + * target_core_action_cit is a ConfigFS group that lives under
> + * /sys/kernel/config/target/core/action.
> + */
> +static const struct config_item_type target_core_action_cit = {
> + .ct_item_ops = NULL,
> + .ct_attrs = NULL,
> + .ct_owner = THIS_MODULE,
> +};
> +
> +/* End functions for struct config_item_type target_core_action_cit */
> +
> /* Start functions for struct config_item_type tb_dev_stat_cit */
>
> static struct config_group *target_core_stat_mkdir(
> @@ -3211,6 +3227,30 @@ void target_setup_backend_cits(struct target_backend *tb)
> target_core_setup_dev_wwn_cit(tb);
> target_core_setup_dev_alua_tg_pt_gps_cit(tb);
> target_core_setup_dev_stat_cit(tb);
> +
> + target_core_setup_mod_action_cit(tb);
> +}
> +
> +int target_setup_backend_action(struct target_backend *tb)
I think it might be best to rename these to:
target_register_backend_action_group
target_unregister_backend_action_group
It seems we are doing the setup and un/registration and unset is not a
common name type in the existing code.
> +{
> + if (!tb->ops->tb_mod_action_attrs)
> + return 0;
> +
> + tb->action_group = configfs_register_default_group(&action_group,
> + tb->ops->name,
> + &tb->tb_mod_action_cit);
> + if (!tb->action_group)
I think you need to do
if (IS_ERR(tb->action_group))
> + return PTR_ERR(tb->action_group);
> +
> + return 0;
> +}
> +
> +void target_unset_backend_action(struct target_backend *tb)
> +{
> + if (!tb->ops->tb_mod_action_attrs)
> + return;
> +
> + configfs_unregister_default_group(tb->action_group);
> }
>
> static int __init target_core_init_configfs(void)
> @@ -3267,6 +3307,12 @@ static int __init target_core_init_configfs(void)
> default_lu_gp = lu_gp;
>
> /*
> + * Create ALUA infrastructure under /sys/kernel/config/target/core/action/
Fix up the ALUA reference in the comment.
> + */
> + config_group_init_type_name(&action_group, "action", &target_core_action_cit);
> + configfs_add_default_group(&action_group, &target_core_hbagroup);
> +
> + /*
> * Register the target_core_mod subsystem with configfs.
> */
> ret = configfs_register_subsystem(subsys);
> diff --git a/drivers/target/target_core_hba.c b/drivers/target/target_core_hba.c
> index 22390e0..6903087 100644
> --- a/drivers/target/target_core_hba.c
> +++ b/drivers/target/target_core_hba.c
> @@ -51,6 +51,7 @@
> int transport_backend_register(const struct target_backend_ops *ops)
> {
> struct target_backend *tb, *old;
> + int ret;
>
> tb = kzalloc(sizeof(*tb), GFP_KERNEL);
> if (!tb)
> @@ -67,11 +68,20 @@ int transport_backend_register(const struct target_backend_ops *ops)
> }
> }
> target_setup_backend_cits(tb);
> +
> + ret = target_setup_backend_action(tb);
> + if (ret) {
> + mutex_unlock(&backend_mutex);
> + kfree(tb);
Just do a goto since we have multiple places doing the same cleanup with
this addition.
> + return ret;
> + }
> +
> list_add_tail(&tb->list, &backend_list);
> mutex_unlock(&backend_mutex);
>
> pr_debug("TCM: Registered subsystem plugin: %s struct module: %p\n",
> ops->name, ops->owner);
> +
Don't add extra formatting.
