devlink: remove linecards lock

Similar to other devlink objects, convert the linecards list to be
protected by devlink instance lock. Alongside with that rename the
create/destroy() functions to devl_* to indicate the devlink instance
lock needs to be held while calling them.
Signed-off-by: Jiri Pirko <jiri@nvidia.com>
Reviewed-by: Ido Schimmel <idosch@nvidia.com>
Reviewed-by: Jacob Keller <jacob.e.keller@intel.com>
Signed-off-by: Jakub Kicinski <kuba@kernel.org>

drivers/net/ethernet/mellanox/mlxsw/core_linecards.c

@@ -1259,9 +1259,9 @@ static int mlxsw_linecard_init(struct mlxsw_core *mlxsw_core,
 	linecard->linecards = linecards;
 	mutex_init(&linecard->lock);
 
-	devlink_linecard = devlink_linecard_create(priv_to_devlink(mlxsw_core),
-						   slot_index, &mlxsw_linecard_ops,
-						   linecard);
+	devlink_linecard = devl_linecard_create(priv_to_devlink(mlxsw_core),
+						slot_index, &mlxsw_linecard_ops,
+						linecard);
 	if (IS_ERR(devlink_linecard))
 		return PTR_ERR(devlink_linecard);
 
@@ -1285,7 +1285,7 @@ static void mlxsw_linecard_fini(struct mlxsw_core *mlxsw_core,
 	if (linecard->active)
 		mlxsw_linecard_active_clear(linecard);
 	mlxsw_linecard_bdev_del(linecard);
-	devlink_linecard_destroy(linecard->devlink_linecard);
+	devl_linecard_destroy(linecard->devlink_linecard);
 	mutex_destroy(&linecard->lock);
 }
 

include/net/devlink.h

@@ -1687,9 +1687,9 @@ void devl_rate_nodes_destroy(struct devlink *devlink);
 void devlink_port_linecard_set(struct devlink_port *devlink_port,
 			       struct devlink_linecard *linecard);
 struct devlink_linecard *
-devlink_linecard_create(struct devlink *devlink, unsigned int linecard_index,
-			const struct devlink_linecard_ops *ops, void *priv);
-void devlink_linecard_destroy(struct devlink_linecard *linecard);
+devl_linecard_create(struct devlink *devlink, unsigned int linecard_index,
+		     const struct devlink_linecard_ops *ops, void *priv);
+void devl_linecard_destroy(struct devlink_linecard *linecard);
 void devlink_linecard_provision_set(struct devlink_linecard *linecard,
 				    const char *type);
 void devlink_linecard_provision_clear(struct devlink_linecard *linecard);

net/devlink/core.c

@@ -247,7 +247,6 @@ struct devlink *devlink_alloc_ns(const struct devlink_ops *ops,
 	mutex_init(&devlink->lock);
 	lockdep_set_class(&devlink->lock, &devlink->lock_key);
 	mutex_init(&devlink->reporters_lock);
-	mutex_init(&devlink->linecards_lock);
 	refcount_set(&devlink->refcount, 1);
 
 	return devlink;
@@ -269,7 +268,6 @@ void devlink_free(struct devlink *devlink)
 {
 	ASSERT_DEVLINK_NOT_REGISTERED(devlink);
 
-	mutex_destroy(&devlink->linecards_lock);
 	mutex_destroy(&devlink->reporters_lock);
 	WARN_ON(!list_empty(&devlink->trap_policer_list));
 	WARN_ON(!list_empty(&devlink->trap_group_list));

net/devlink/devl_internal.h

@@ -38,7 +38,6 @@ struct devlink {
 	struct list_head trap_group_list;
 	struct list_head trap_policer_list;
 	struct list_head linecard_list;
-	struct mutex linecards_lock; /* protects linecard_list */
 	const struct devlink_ops *ops;
 	u64 features;
 	struct xarray snapshot_ids;

net/devlink/leftover.c

@@ -282,13 +282,10 @@ devlink_linecard_get_from_attrs(struct devlink *devlink, struct nlattr **attrs)
 		u32 linecard_index = nla_get_u32(attrs[DEVLINK_ATTR_LINECARD_INDEX]);
 		struct devlink_linecard *linecard;
 
-		mutex_lock(&devlink->linecards_lock);
 		linecard = devlink_linecard_get_by_index(devlink, linecard_index);
-		if (linecard)
-			refcount_inc(&linecard->refcount);
-		mutex_unlock(&devlink->linecards_lock);
 		if (!linecard)
 			return ERR_PTR(-ENODEV);
+		refcount_inc(&linecard->refcount);
 		return linecard;
 	}
 	return ERR_PTR(-EINVAL);
@@ -2129,7 +2126,7 @@ static int devlink_nl_cmd_linecard_get_dumpit(struct sk_buff *msg,
 	devlink_dump_for_each_instance_get(msg, state, devlink) {
 		int idx = 0;
 
-		mutex_lock(&devlink->linecards_lock);
+		devl_lock(devlink);
 		if (!devl_is_registered(devlink))
 			goto next_devlink;
 
@@ -2147,7 +2144,7 @@ static int devlink_nl_cmd_linecard_get_dumpit(struct sk_buff *msg,
 						       cb->extack);
 			mutex_unlock(&linecard->state_lock);
 			if (err) {
-				mutex_unlock(&devlink->linecards_lock);
+				devl_unlock(devlink);
 				devlink_put(devlink);
 				state->idx = idx;
 				goto out;
@@ -2155,7 +2152,7 @@ static int devlink_nl_cmd_linecard_get_dumpit(struct sk_buff *msg,
 			idx++;
 		}
 next_devlink:
-		mutex_unlock(&devlink->linecards_lock);
+		devl_unlock(devlink);
 		devlink_put(devlink);
 	}
 out:
@@ -10223,7 +10220,7 @@ static void devlink_linecard_types_fini(struct devlink_linecard *linecard)
 }
 
 /**
- *	devlink_linecard_create - Create devlink linecard
+ *	devl_linecard_create - Create devlink linecard
  *
  *	@devlink: devlink
  *	@linecard_index: driver-specific numerical identifier of the linecard
@@ -10236,8 +10233,8 @@ static void devlink_linecard_types_fini(struct devlink_linecard *linecard)
  *	Return: Line card structure or an ERR_PTR() encoded error code.
  */
 struct devlink_linecard *
-devlink_linecard_create(struct devlink *devlink, unsigned int linecard_index,
-			const struct devlink_linecard_ops *ops, void *priv)
+devl_linecard_create(struct devlink *devlink, unsigned int linecard_index,
+		     const struct devlink_linecard_ops *ops, void *priv)
 {
 	struct devlink_linecard *linecard;
 	int err;
@@ -10246,17 +10243,12 @@ devlink_linecard_create(struct devlink *devlink, unsigned int linecard_index,
 		    !ops->types_count || !ops->types_get))
 		return ERR_PTR(-EINVAL);
 
-	mutex_lock(&devlink->linecards_lock);
-	if (devlink_linecard_index_exists(devlink, linecard_index)) {
-		mutex_unlock(&devlink->linecards_lock);
+	if (devlink_linecard_index_exists(devlink, linecard_index))
 		return ERR_PTR(-EEXIST);
-	}
 
 	linecard = kzalloc(sizeof(*linecard), GFP_KERNEL);
-	if (!linecard) {
-		mutex_unlock(&devlink->linecards_lock);
+	if (!linecard)
 		return ERR_PTR(-ENOMEM);
-	}
 
 	linecard->devlink = devlink;
 	linecard->index = linecard_index;
@@ -10269,35 +10261,29 @@ devlink_linecard_create(struct devlink *devlink, unsigned int linecard_index,
 	if (err) {
 		mutex_destroy(&linecard->state_lock);
 		kfree(linecard);
-		mutex_unlock(&devlink->linecards_lock);
 		return ERR_PTR(err);
 	}
 
 	list_add_tail(&linecard->list, &devlink->linecard_list);
 	refcount_set(&linecard->refcount, 1);
-	mutex_unlock(&devlink->linecards_lock);
 	devlink_linecard_notify(linecard, DEVLINK_CMD_LINECARD_NEW);
 	return linecard;
 }
-EXPORT_SYMBOL_GPL(devlink_linecard_create);
+EXPORT_SYMBOL_GPL(devl_linecard_create);
 
 /**
- *	devlink_linecard_destroy - Destroy devlink linecard
+ *	devl_linecard_destroy - Destroy devlink linecard
  *
  *	@linecard: devlink linecard
  */
-void devlink_linecard_destroy(struct devlink_linecard *linecard)
+void devl_linecard_destroy(struct devlink_linecard *linecard)
 {
-	struct devlink *devlink = linecard->devlink;
-
 	devlink_linecard_notify(linecard, DEVLINK_CMD_LINECARD_DEL);
-	mutex_lock(&devlink->linecards_lock);
 	list_del(&linecard->list);
 	devlink_linecard_types_fini(linecard);
-	mutex_unlock(&devlink->linecards_lock);
 	devlink_linecard_put(linecard);
 }
-EXPORT_SYMBOL_GPL(devlink_linecard_destroy);
+EXPORT_SYMBOL_GPL(devl_linecard_destroy);
 
 /**
  *	devlink_linecard_provision_set - Set provisioning on linecard