ethtool: Add ability to flash transceiver modules' firmware

Add the ability to flash the modules' firmware by implementing the
interface between the user space and the kernel.

Example from a succeeding implementation:

# ethtool --flash-module-firmware swp40 file test.bin

Transceiver module firmware flashing started for device swp40
Transceiver module firmware flashing in progress for device swp40
Progress: 99%
Transceiver module firmware flashing completed for device swp40

In addition, add infrastructure that allows modules to set socket-specific
private data. This ensures that when a socket is closed from user space
during the flashing process, the right socket halts sending notifications
to user space until the work item is completed.

Signed-off-by: Danielle Ratson <[e-mail]>
Reviewed-by: Petr Machata <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/ethtool/module.c

···
 // SPDX-License-Identifier: GPL-2.0-only
 
 #include <linux/ethtool.h>
+#include <linux/firmware.h>
+#include <linux/sfp.h>
+#include <net/devlink.h>
 
 #include "netlink.h"
 #include "common.h"
···
 
 	if (!ops->get_module_power_mode)
 		return 0;
+
+	if (dev->module_fw_flash_in_progress) {
+		NL_SET_ERR_MSG(extack,
+			       "Module firmware flashing is in progress");
+		return -EBUSY;
+	}
 
 	return ops->get_module_power_mode(dev, &data->power, extack);
 }
···
 	if (!tb[ETHTOOL_A_MODULE_POWER_MODE_POLICY])
 		return 0;
 
+	if (req_info->dev->module_fw_flash_in_progress) {
+		NL_SET_ERR_MSG(info->extack,
+			       "Module firmware flashing is in progress");
+		return -EBUSY;
+	}
+
 	if (!ops->get_module_power_mode || !ops->set_module_power_mode) {
 		NL_SET_ERR_MSG_ATTR(info->extack,
 				    tb[ETHTOOL_A_MODULE_POWER_MODE_POLICY],
···
 	.set			= ethnl_set_module,
 	.set_ntf_cmd		= ETHTOOL_MSG_MODULE_NTF,
 };
+
+/* MODULE_FW_FLASH_ACT */
+
+const struct nla_policy
+ethnl_module_fw_flash_act_policy[ETHTOOL_A_MODULE_FW_FLASH_PASSWORD + 1] = {
+	[ETHTOOL_A_MODULE_FW_FLASH_HEADER] =
+		NLA_POLICY_NESTED(ethnl_header_policy),
+	[ETHTOOL_A_MODULE_FW_FLASH_FILE_NAME] = { .type = NLA_NUL_STRING },
+	[ETHTOOL_A_MODULE_FW_FLASH_PASSWORD] = { .type = NLA_U32 },
+};
+
+static LIST_HEAD(module_fw_flash_work_list);
+static DEFINE_SPINLOCK(module_fw_flash_work_list_lock);
+
+static int
+module_flash_fw_work_list_add(struct ethtool_module_fw_flash *module_fw,
+			      struct genl_info *info)
+{
+	struct ethtool_module_fw_flash *work;
+
+	/* First, check if already registered. */
+	spin_lock(&module_fw_flash_work_list_lock);
+	list_for_each_entry(work, &module_fw_flash_work_list, list) {
+		if (work->fw_update.ntf_params.portid == info->snd_portid &&
+		    work->fw_update.dev == module_fw->fw_update.dev) {
+			spin_unlock(&module_fw_flash_work_list_lock);
+			return -EALREADY;
+		}
+	}
+
+	list_add_tail(&module_fw->list, &module_fw_flash_work_list);
+	spin_unlock(&module_fw_flash_work_list_lock);
+
+	return 0;
+}
+
+static void module_flash_fw_work_list_del(struct list_head *list)
+{
+	spin_lock(&module_fw_flash_work_list_lock);
+	list_del(list);
+	spin_unlock(&module_fw_flash_work_list_lock);
+}
+
+static void module_flash_fw_work(struct work_struct *work)
+{
+	struct ethtool_module_fw_flash *module_fw;
+
+	module_fw = container_of(work, struct ethtool_module_fw_flash, work);
+
+	ethtool_cmis_fw_update(&module_fw->fw_update);
+
+	module_flash_fw_work_list_del(&module_fw->list);
+	module_fw->fw_update.dev->module_fw_flash_in_progress = false;
+	netdev_put(module_fw->fw_update.dev, &module_fw->dev_tracker);
+	release_firmware(module_fw->fw_update.fw);
+	kfree(module_fw);
+}
+
+#define MODULE_EEPROM_PHYS_ID_PAGE	0
+#define MODULE_EEPROM_PHYS_ID_I2C_ADDR	0x50
+
+static int module_flash_fw_work_init(struct ethtool_module_fw_flash *module_fw,
+				     struct net_device *dev,
+				     struct netlink_ext_ack *extack)
+{
+	const struct ethtool_ops *ops = dev->ethtool_ops;
+	struct ethtool_module_eeprom page_data = {};
+	u8 phys_id;
+	int err;
+
+	/* Fetch the SFF-8024 Identifier Value. For all supported standards, it
+	 * is located at I2C address 0x50, byte 0. See section 4.1 in SFF-8024,
+	 * revision 4.9.
+	 */
+	page_data.page = MODULE_EEPROM_PHYS_ID_PAGE;
+	page_data.offset = SFP_PHYS_ID;
+	page_data.length = sizeof(phys_id);
+	page_data.i2c_address = MODULE_EEPROM_PHYS_ID_I2C_ADDR;
+	page_data.data = &phys_id;
+
+	err = ops->get_module_eeprom_by_page(dev, &page_data, extack);
+	if (err < 0)
+		return err;
+
+	switch (phys_id) {
+	case SFF8024_ID_QSFP_DD:
+	case SFF8024_ID_OSFP:
+	case SFF8024_ID_DSFP:
+	case SFF8024_ID_QSFP_PLUS_CMIS:
+	case SFF8024_ID_SFP_DD_CMIS:
+	case SFF8024_ID_SFP_PLUS_CMIS:
+		INIT_WORK(&module_fw->work, module_flash_fw_work);
+		break;
+	default:
+		NL_SET_ERR_MSG(extack,
+			       "Module type does not support firmware flashing");
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+void ethnl_module_fw_flash_sock_destroy(struct ethnl_sock_priv *sk_priv)
+{
+	struct ethtool_module_fw_flash *work;
+
+	spin_lock(&module_fw_flash_work_list_lock);
+	list_for_each_entry(work, &module_fw_flash_work_list, list) {
+		if (work->fw_update.dev == sk_priv->dev &&
+		    work->fw_update.ntf_params.portid == sk_priv->portid) {
+			work->fw_update.ntf_params.closed_sock = true;
+			break;
+		}
+	}
+	spin_unlock(&module_fw_flash_work_list_lock);
+}
+
+static int
+module_flash_fw_schedule(struct net_device *dev, const char *file_name,
+			 struct ethtool_module_fw_flash_params *params,
+			 struct sk_buff *skb, struct genl_info *info)
+{
+	struct ethtool_cmis_fw_update_params *fw_update;
+	struct ethtool_module_fw_flash *module_fw;
+	int err;
+
+	module_fw = kzalloc(sizeof(*module_fw), GFP_KERNEL);
+	if (!module_fw)
+		return -ENOMEM;
+
+	fw_update = &module_fw->fw_update;
+	fw_update->params = *params;
+	err = request_firmware_direct(&fw_update->fw,
+				      file_name, &dev->dev);
+	if (err) {
+		NL_SET_ERR_MSG(info->extack,
+			       "Failed to request module firmware image");
+		goto err_free;
+	}
+
+	err = module_flash_fw_work_init(module_fw, dev, info->extack);
+	if (err < 0)
+		goto err_release_firmware;
+
+	dev->module_fw_flash_in_progress = true;
+	netdev_hold(dev, &module_fw->dev_tracker, GFP_KERNEL);
+	fw_update->dev = dev;
+	fw_update->ntf_params.portid = info->snd_portid;
+	fw_update->ntf_params.seq = info->snd_seq;
+	fw_update->ntf_params.closed_sock = false;
+
+	err = ethnl_sock_priv_set(skb, dev, fw_update->ntf_params.portid,
+				  ETHTOOL_SOCK_TYPE_MODULE_FW_FLASH);
+	if (err < 0)
+		goto err_release_firmware;
+
+	err = module_flash_fw_work_list_add(module_fw, info);
+	if (err < 0)
+		goto err_release_firmware;
+
+	schedule_work(&module_fw->work);
+
+	return 0;
+
+err_release_firmware:
+	release_firmware(fw_update->fw);
+err_free:
+	kfree(module_fw);
+	return err;
+}
+
+static int module_flash_fw(struct net_device *dev, struct nlattr **tb,
+			   struct sk_buff *skb, struct genl_info *info)
+{
+	struct ethtool_module_fw_flash_params params = {};
+	const char *file_name;
+	struct nlattr *attr;
+
+	if (GENL_REQ_ATTR_CHECK(info, ETHTOOL_A_MODULE_FW_FLASH_FILE_NAME))
+		return -EINVAL;
+
+	file_name = nla_data(tb[ETHTOOL_A_MODULE_FW_FLASH_FILE_NAME]);
+
+	attr = tb[ETHTOOL_A_MODULE_FW_FLASH_PASSWORD];
+	if (attr) {
+		params.password = cpu_to_be32(nla_get_u32(attr));
+		params.password_valid = true;
+	}
+
+	return module_flash_fw_schedule(dev, file_name, &params, skb, info);
+}
+
+static int ethnl_module_fw_flash_validate(struct net_device *dev,
+					  struct netlink_ext_ack *extack)
+{
+	struct devlink_port *devlink_port = dev->devlink_port;
+	const struct ethtool_ops *ops = dev->ethtool_ops;
+
+	if (!ops->set_module_eeprom_by_page ||
+	    !ops->get_module_eeprom_by_page) {
+		NL_SET_ERR_MSG(extack,
+			       "Flashing module firmware is not supported by this device");
+		return -EOPNOTSUPP;
+	}
+
+	if (!ops->reset) {
+		NL_SET_ERR_MSG(extack,
+			       "Reset module is not supported by this device, so flashing is not permitted");
+		return -EOPNOTSUPP;
+	}
+
+	if (dev->module_fw_flash_in_progress) {
+		NL_SET_ERR_MSG(extack, "Module firmware flashing already in progress");
+		return -EBUSY;
+	}
+
+	if (dev->flags & IFF_UP) {
+		NL_SET_ERR_MSG(extack, "Netdevice is up, so flashing is not permitted");
+		return -EBUSY;
+	}
+
+	if (devlink_port && devlink_port->attrs.split) {
+		NL_SET_ERR_MSG(extack, "Can't perform firmware flashing on a split port");
+		return -EOPNOTSUPP;
+	}
+
+	return 0;
+}
+
+int ethnl_act_module_fw_flash(struct sk_buff *skb, struct genl_info *info)
+{
+	struct ethnl_req_info req_info = {};
+	struct nlattr **tb = info->attrs;
+	struct net_device *dev;
+	int ret;
+
+	ret = ethnl_parse_header_dev_get(&req_info,
+					 tb[ETHTOOL_A_MODULE_FW_FLASH_HEADER],
+					 genl_info_net(info), info->extack,
+					 true);
+	if (ret < 0)
+		return ret;
+	dev = req_info.dev;
+
+	rtnl_lock();
+	ret = ethnl_ops_begin(dev);
+	if (ret < 0)
+		goto out_rtnl;
+
+	ret = ethnl_module_fw_flash_validate(dev, info->extack);
+	if (ret < 0)
+		goto out_rtnl;
+
+	ret = module_flash_fw(dev, tb, skb, info);
+
+	ethnl_ops_complete(dev);
+
+out_rtnl:
+	rtnl_unlock();
+	ethnl_parse_header_dev_put(&req_info);
+	return ret;
+}
 
 /* MODULE_FW_FLASH_NTF */
 

net/ethtool/module_fw.h

···
 /* SPDX-License-Identifier: GPL-2.0-only */
 
 #include <uapi/linux/ethtool.h>
+#include "netlink.h"
 
 /**
  * struct ethnl_module_fw_flash_ntf_params - module firmware flashing
···
 	struct work_struct work;
 	struct ethtool_cmis_fw_update_params fw_update;
 };
+
+void ethnl_module_fw_flash_sock_destroy(struct ethnl_sock_priv *sk_priv);
 
 void
 ethnl_module_fw_flash_ntf_err(struct net_device *dev,

net/ethtool/netlink.c

···
 #include <linux/ethtool_netlink.h>
 #include <linux/pm_runtime.h>
 #include "netlink.h"
+#include "module_fw.h"
 
 static struct genl_family ethtool_genl_family;
 
···
 	[ETHTOOL_A_HEADER_FLAGS]	= NLA_POLICY_MASK(NLA_U32,
 							  ETHTOOL_FLAGS_STATS),
 };
+
+int ethnl_sock_priv_set(struct sk_buff *skb, struct net_device *dev, u32 portid,
+			enum ethnl_sock_type type)
+{
+	struct ethnl_sock_priv *sk_priv;
+
+	sk_priv = genl_sk_priv_get(&ethtool_genl_family, NETLINK_CB(skb).sk);
+	if (IS_ERR(sk_priv))
+		return PTR_ERR(sk_priv);
+
+	sk_priv->dev = dev;
+	sk_priv->portid = portid;
+	sk_priv->type = type;
+
+	return 0;
+}
+
+static void ethnl_sock_priv_destroy(void *priv)
+{
+	struct ethnl_sock_priv *sk_priv = priv;
+
+	switch (sk_priv->type) {
+	case ETHTOOL_SOCK_TYPE_MODULE_FW_FLASH:
+		ethnl_module_fw_flash_sock_destroy(sk_priv);
+		break;
+	default:
+		break;
+	}
+}
 
 int ethnl_ops_begin(struct net_device *dev)
 {
···
 		.policy = ethnl_mm_set_policy,
 		.maxattr = ARRAY_SIZE(ethnl_mm_set_policy) - 1,
 	},
+	{
+		.cmd	= ETHTOOL_MSG_MODULE_FW_FLASH_ACT,
+		.flags	= GENL_UNS_ADMIN_PERM,
+		.doit	= ethnl_act_module_fw_flash,
+		.policy	= ethnl_module_fw_flash_act_policy,
+		.maxattr = ARRAY_SIZE(ethnl_module_fw_flash_act_policy) - 1,
+	},
 };
 
 static const struct genl_multicast_group ethtool_nl_mcgrps[] = {
···
 	.resv_start_op	= ETHTOOL_MSG_MODULE_GET + 1,
 	.mcgrps		= ethtool_nl_mcgrps,
 	.n_mcgrps	= ARRAY_SIZE(ethtool_nl_mcgrps),
+	.sock_priv_size		= sizeof(struct ethnl_sock_priv),
+	.sock_priv_destroy	= ethnl_sock_priv_destroy,
 };
 
 /* module setup */

net/ethtool/netlink.h

···
 int ethnl_ops_begin(struct net_device *dev);
 void ethnl_ops_complete(struct net_device *dev);
 
+enum ethnl_sock_type {
+	ETHTOOL_SOCK_TYPE_MODULE_FW_FLASH,
+};
+
+struct ethnl_sock_priv {
+	struct net_device *dev;
+	u32 portid;
+	enum ethnl_sock_type type;
+};
+
+int ethnl_sock_priv_set(struct sk_buff *skb, struct net_device *dev, u32 portid,
+			enum ethnl_sock_type type);
+
 /**
  * struct ethnl_request_ops - unified handling of GET and SET requests
  * @request_cmd:      command id for request (GET)
···
 extern const struct nla_policy ethnl_plca_get_status_policy[ETHTOOL_A_PLCA_HEADER + 1];
 extern const struct nla_policy ethnl_mm_get_policy[ETHTOOL_A_MM_HEADER + 1];
 extern const struct nla_policy ethnl_mm_set_policy[ETHTOOL_A_MM_MAX + 1];
+extern const struct nla_policy ethnl_module_fw_flash_act_policy[ETHTOOL_A_MODULE_FW_FLASH_PASSWORD + 1];
 
 int ethnl_set_features(struct sk_buff *skb, struct genl_info *info);
 int ethnl_act_cable_test(struct sk_buff *skb, struct genl_info *info);
···
 int ethnl_tunnel_info_doit(struct sk_buff *skb, struct genl_info *info);
 int ethnl_tunnel_info_start(struct netlink_callback *cb);
 int ethnl_tunnel_info_dumpit(struct sk_buff *skb, struct netlink_callback *cb);
+int ethnl_act_module_fw_flash(struct sk_buff *skb, struct genl_info *info);
 
 extern const char stats_std_names[__ETHTOOL_STATS_CNT][ETH_GSTRING_LEN];
 extern const char stats_eth_phy_names[__ETHTOOL_A_STATS_ETH_PHY_CNT][ETH_GSTRING_LEN];