[PATCH net-next v6 4/9] ethtool: Add flashing transceiver modules' firmware notifications ability

[Danielle Ratson <danieller@xxxxxxxxxx>]

Add progress notifications ability to user space while flashing modules'
firmware by implementing the interface between the user space and the
kernel.

Signed-off-by: Danielle Ratson <danieller@xxxxxxxxxx>
Reviewed-by: Petr Machata <petrm@xxxxxxxxxx>
---

Notes:
    v6:
    	* Reserve '1' more place on SKB for NUL terminator in the error
    	  message string.
    	* Add more prints on error flow, re-write the printing function
    	  and add ethnl_module_fw_flash_ntf_put_err().
    	* Change the communication method so notification will be sent
    	  in unicast instead of multicast.
    	* Add new 'struct ethnl_module_fw_flash_ntf_params' that holds
    	  the relevant info for unicast communication and use it to send
    	  notification to the specific socket.
    	* s/nla_put_u64_64bit/nla_put_uint/
    
    v2:
    	* Increase err_msg length.

 net/ethtool/module.c    | 117 ++++++++++++++++++++++++++++++++++++++++
 net/ethtool/module_fw.h |  31 +++++++++++
 net/ethtool/netlink.c   |   5 ++
 net/ethtool/netlink.h   |   1 +
 4 files changed, 154 insertions(+)
 create mode 100644 net/ethtool/module_fw.h

diff --git a/net/ethtool/module.c b/net/ethtool/module.c
index ceb575efc290..932415bd44c6 100644
--- a/net/ethtool/module.c
+++ b/net/ethtool/module.c
@@ -5,6 +5,7 @@
 #include "netlink.h"
 #include "common.h"
 #include "bitset.h"
+#include "module_fw.h"
 
 struct module_req_info {
 	struct ethnl_req_info base;
@@ -158,3 +159,119 @@ const struct ethnl_request_ops ethnl_module_request_ops = {
 	.set			= ethnl_set_module,
 	.set_ntf_cmd		= ETHTOOL_MSG_MODULE_NTF,
 };
+
+/* MODULE_FW_FLASH_NTF */
+
+static int
+ethnl_module_fw_flash_ntf_put_err(struct sk_buff *skb, char *err_msg,
+				  char *sub_err_msg)
+{
+	int err_msg_len, sub_err_msg_len, total_len;
+	struct nlattr *attr;
+
+	if (!err_msg)
+		return 0;
+
+	err_msg_len = strlen(err_msg);
+	total_len = err_msg_len + 2; /* For period and NUL. */
+
+	if (sub_err_msg) {
+		sub_err_msg_len = strlen(sub_err_msg);
+		total_len += sub_err_msg_len + 2; /* For ", ". */
+	}
+
+	attr = nla_reserve(skb, ETHTOOL_A_MODULE_FW_FLASH_STATUS_MSG,
+			   total_len);
+	if (!attr)
+		return PTR_ERR(attr);
+
+	if (sub_err_msg)
+		sprintf(nla_data(attr), "%s, %s.", err_msg, sub_err_msg);
+	else
+		sprintf(nla_data(attr), "%s.", err_msg);
+
+	return 0;
+}
+
+static void
+ethnl_module_fw_flash_ntf(struct net_device *dev,
+			  enum ethtool_module_fw_flash_status status,
+			  struct ethnl_module_fw_flash_ntf_params *ntf_params,
+			  char *err_msg, char *sub_err_msg,
+			  u64 done, u64 total)
+{
+	struct sk_buff *skb;
+	void *hdr;
+	int ret;
+
+	if (ntf_params->closed_sock)
+		return;
+
+	skb = genlmsg_new(NLMSG_GOODSIZE, GFP_KERNEL);
+	if (!skb)
+		return;
+
+	hdr = ethnl_unicast_put(skb, ntf_params->portid, ntf_params->seq,
+				ETHTOOL_MSG_MODULE_FW_FLASH_NTF);
+	if (!hdr)
+		goto err_skb;
+
+	ret = ethnl_fill_reply_header(skb, dev,
+				      ETHTOOL_A_MODULE_FW_FLASH_HEADER);
+	if (ret < 0)
+		goto err_skb;
+
+	if (nla_put_u32(skb, ETHTOOL_A_MODULE_FW_FLASH_STATUS, status))
+		goto err_skb;
+
+	ret = ethnl_module_fw_flash_ntf_put_err(skb, err_msg, sub_err_msg);
+	if (ret < 0)
+		goto err_skb;
+
+	if (nla_put_uint(skb, ETHTOOL_A_MODULE_FW_FLASH_DONE, done))
+		goto err_skb;
+
+	if (nla_put_uint(skb, ETHTOOL_A_MODULE_FW_FLASH_TOTAL, total))
+		goto err_skb;
+
+	genlmsg_end(skb, hdr);
+	genlmsg_unicast(dev_net(dev), skb, ntf_params->portid);
+	return;
+
+err_skb:
+	nlmsg_free(skb);
+}
+
+void ethnl_module_fw_flash_ntf_err(struct net_device *dev,
+				   struct ethnl_module_fw_flash_ntf_params *params,
+				   char *err_msg, char *sub_err_msg)
+{
+	ethnl_module_fw_flash_ntf(dev, ETHTOOL_MODULE_FW_FLASH_STATUS_ERROR,
+				  params, err_msg, sub_err_msg, 0, 0);
+}
+
+void
+ethnl_module_fw_flash_ntf_start(struct net_device *dev,
+				struct ethnl_module_fw_flash_ntf_params *params)
+{
+	ethnl_module_fw_flash_ntf(dev, ETHTOOL_MODULE_FW_FLASH_STATUS_STARTED,
+				  params, NULL, NULL, 0, 0);
+}
+
+void
+ethnl_module_fw_flash_ntf_complete(struct net_device *dev,
+				   struct ethnl_module_fw_flash_ntf_params *params)
+{
+	ethnl_module_fw_flash_ntf(dev, ETHTOOL_MODULE_FW_FLASH_STATUS_COMPLETED,
+				  params, NULL, NULL, 0, 0);
+}
+
+void
+ethnl_module_fw_flash_ntf_in_progress(struct net_device *dev,
+				      struct ethnl_module_fw_flash_ntf_params *params,
+				      u64 done, u64 total)
+{
+	ethnl_module_fw_flash_ntf(dev,
+				  ETHTOOL_MODULE_FW_FLASH_STATUS_IN_PROGRESS,
+				  params, NULL, NULL, done, total);
+}
diff --git a/net/ethtool/module_fw.h b/net/ethtool/module_fw.h
new file mode 100644
index 000000000000..ee4a291ac1d4
--- /dev/null
+++ b/net/ethtool/module_fw.h
@@ -0,0 +1,31 @@
+/* SPDX-License-Identifier: GPL-2.0-only */
+
+#include <uapi/linux/ethtool.h>
+
+/**
+ * struct ethnl_module_fw_flash_ntf_params - module firmware flashing
+ *						notifications parameters
+ * @portid: Netlink portid of sender.
+ * @seq: Sequence number of sender.
+ * @closed_sock: Indicates whether the socket was closed from user space.
+ */
+struct ethnl_module_fw_flash_ntf_params {
+	u32 portid;
+	u32 seq;
+	bool closed_sock;
+};
+
+void
+ethnl_module_fw_flash_ntf_err(struct net_device *dev,
+			      struct ethnl_module_fw_flash_ntf_params *params,
+			      char *err_msg, char *sub_err_msg);
+void
+ethnl_module_fw_flash_ntf_start(struct net_device *dev,
+				struct ethnl_module_fw_flash_ntf_params *params);
+void
+ethnl_module_fw_flash_ntf_complete(struct net_device *dev,
+				   struct ethnl_module_fw_flash_ntf_params *params);
+void
+ethnl_module_fw_flash_ntf_in_progress(struct net_device *dev,
+				      struct ethnl_module_fw_flash_ntf_params *params,
+				      u64 done, u64 total);
diff --git a/net/ethtool/netlink.c b/net/ethtool/netlink.c
index bd04f28d5cf4..393ce668fb04 100644
--- a/net/ethtool/netlink.c
+++ b/net/ethtool/netlink.c
@@ -239,6 +239,11 @@ void *ethnl_bcastmsg_put(struct sk_buff *skb, u8 cmd)
 			   cmd);
 }
 
+void *ethnl_unicast_put(struct sk_buff *skb, u32 portid, u32 seq, u8 cmd)
+{
+	return genlmsg_put(skb, portid, seq, &ethtool_genl_family, 0, cmd);
+}
+
 int ethnl_multicast(struct sk_buff *skb, struct net_device *dev)
 {
 	return genlmsg_multicast_netns(&ethtool_genl_family, dev_net(dev), skb,
diff --git a/net/ethtool/netlink.h b/net/ethtool/netlink.h
index 9a333a8d04c1..5e6c6a7b7adc 100644
--- a/net/ethtool/netlink.h
+++ b/net/ethtool/netlink.h
@@ -21,6 +21,7 @@ struct sk_buff *ethnl_reply_init(size_t payload, struct net_device *dev, u8 cmd,
 				 void **ehdrp);
 void *ethnl_dump_put(struct sk_buff *skb, struct netlink_callback *cb, u8 cmd);
 void *ethnl_bcastmsg_put(struct sk_buff *skb, u8 cmd);
+void *ethnl_unicast_put(struct sk_buff *skb, u32 portid, u32 seq, u8 cmd);
 int ethnl_multicast(struct sk_buff *skb, struct net_device *dev);
 
 /**
-- 
2.45.0