From fdb457a0ebb57c99fb987d0e34b2549f10dd4161 Mon Sep 17 00:00:00 2001
From: Ido Schimmel <idosch@nvidia.com>
Date: Tue, 12 Oct 2021 16:25:21 +0300
Subject: [PATCH 22/35] netlink: eeprom: Export a function to request an EEPROM
 page

The function will be used by the EEPROM parsing code (e.g., cmis.c) to
request a specific page for parsing.

All the data buffers used to store EEPROM page contents are stored on a
linked list that is flushed on exit. This relieves callers from the need
to explicitly free the requested pages.

Signed-off-by: Ido Schimmel <idosch@nvidia.com>
---
 netlink/extapi.h        |  11 +++++
 netlink/module-eeprom.c | 105 ++++++++++++++++++++++++++++++++++++++++
 2 files changed, 116 insertions(+)

diff --git a/netlink/extapi.h b/netlink/extapi.h
index 91bf02b5e3be..129e2931d01d 100644
--- a/netlink/extapi.h
+++ b/netlink/extapi.h
@@ -48,6 +48,9 @@ int nl_getmodule(struct cmd_context *ctx);
 
 void nl_monitor_usage(void);
 
+int nl_get_eeprom_page(struct cmd_context *ctx,
+		       struct ethtool_module_eeprom *request);
+
 #else /* ETHTOOL_ENABLE_NETLINK */
 
 static inline void netlink_run_handler(struct cmd_context *ctx __maybe_unused,
@@ -73,6 +76,14 @@ static inline void nl_monitor_usage(void)
 {
 }
 
+static inline int
+nl_get_eeprom_page(struct cmd_context *ctx __maybe_unused,
+		   struct ethtool_module_eeprom *request __maybe_unused)
+{
+	fprintf(stderr, "Netlink not supported by ethtool.\n");
+	return -EOPNOTSUPP;
+}
+
 #define nl_gset			NULL
 #define nl_sset			NULL
 #define nl_permaddr		NULL
diff --git a/netlink/module-eeprom.c b/netlink/module-eeprom.c
index 101d5943c2bc..ee5508840157 100644
--- a/netlink/module-eeprom.c
+++ b/netlink/module-eeprom.c
@@ -341,6 +341,110 @@ static void decoder_print(void)
 }
 #endif
 
+static struct list_head eeprom_page_list = LIST_HEAD_INIT(eeprom_page_list);
+
+struct eeprom_page_entry {
+	struct list_head list;	/* Member of eeprom_page_list */
+	void *data;
+};
+
+static int eeprom_page_list_add(void *data)
+{
+	struct eeprom_page_entry *entry;
+
+	entry = malloc(sizeof(*entry));
+	if (!entry)
+		return -ENOMEM;
+
+	entry->data = data;
+	list_add(&entry->list, &eeprom_page_list);
+
+	return 0;
+}
+
+static void eeprom_page_list_flush(void)
+{
+	struct eeprom_page_entry *entry;
+	struct list_head *head, *next;
+
+	list_for_each_safe(head, next, &eeprom_page_list) {
+		entry = (struct eeprom_page_entry *) head;
+		free(entry->data);
+		list_del(head);
+		free(entry);
+	}
+}
+
+static int get_eeprom_page_reply_cb(const struct nlmsghdr *nlhdr, void *data)
+{
+	const struct nlattr *tb[ETHTOOL_A_MODULE_EEPROM_DATA + 1] = {};
+	struct ethtool_module_eeprom *request = data;
+	DECLARE_ATTR_TB_INFO(tb);
+	u8 *eeprom_data;
+	int ret;
+
+	ret = mnl_attr_parse(nlhdr, GENL_HDRLEN, attr_cb, &tb_info);
+	if (ret < 0)
+		return ret;
+
+	if (!tb[ETHTOOL_A_MODULE_EEPROM_DATA])
+		return MNL_CB_ERROR;
+
+	eeprom_data = mnl_attr_get_payload(tb[ETHTOOL_A_MODULE_EEPROM_DATA]);
+	request->data = malloc(request->length);
+	if (!request->data)
+		return MNL_CB_ERROR;
+	memcpy(request->data, eeprom_data, request->length);
+
+	ret = eeprom_page_list_add(request->data);
+	if (ret < 0)
+		goto err_list_add;
+
+	return MNL_CB_OK;
+
+err_list_add:
+	free(request->data);
+	return MNL_CB_ERROR;
+}
+
+int nl_get_eeprom_page(struct cmd_context *ctx,
+		       struct ethtool_module_eeprom *request)
+{
+	struct nl_context *nlctx = ctx->nlctx;
+	struct nl_socket *nlsock;
+	struct nl_msg_buff *msg;
+	int ret;
+
+	if (!request || request->i2c_address > ETH_I2C_MAX_ADDRESS)
+		return -EINVAL;
+
+	nlsock = nlctx->ethnl_socket;
+	msg = &nlsock->msgbuff;
+
+	ret = nlsock_prep_get_request(nlsock, ETHTOOL_MSG_MODULE_EEPROM_GET,
+				      ETHTOOL_A_MODULE_EEPROM_HEADER, 0);
+	if (ret < 0)
+		return ret;
+
+	if (ethnla_put_u32(msg, ETHTOOL_A_MODULE_EEPROM_LENGTH,
+			   request->length) ||
+	    ethnla_put_u32(msg, ETHTOOL_A_MODULE_EEPROM_OFFSET,
+			   request->offset) ||
+	    ethnla_put_u8(msg, ETHTOOL_A_MODULE_EEPROM_PAGE,
+			  request->page) ||
+	    ethnla_put_u8(msg, ETHTOOL_A_MODULE_EEPROM_BANK,
+			  request->bank) ||
+	    ethnla_put_u8(msg, ETHTOOL_A_MODULE_EEPROM_I2C_ADDRESS,
+			  request->i2c_address))
+		return -EMSGSIZE;
+
+	ret = nlsock_sendmsg(nlsock, NULL);
+	if (ret < 0)
+		return ret;
+	return nlsock_process_reply(nlsock, get_eeprom_page_reply_cb,
+				    (void *)request);
+}
+
 int nl_getmodule(struct cmd_context *ctx)
 {
 	struct cmd_params getmodule_cmd_params = {};
@@ -425,6 +529,7 @@ int nl_getmodule(struct cmd_context *ctx)
 	}
 
 cleanup:
+	eeprom_page_list_flush();
 	cache_free();
 	return ret;
 }
-- 
2.35.1