xref: /openbmc/linux/net/ethtool/eeprom.c (revision 9aa2cba7)
1 // SPDX-License-Identifier: GPL-2.0-only
2 
3 #include <linux/ethtool.h>
4 #include <linux/sfp.h>
5 #include "netlink.h"
6 #include "common.h"
7 
8 struct eeprom_req_info {
9 	struct ethnl_req_info	base;
10 	u32			offset;
11 	u32			length;
12 	u8			page;
13 	u8			bank;
14 	u8			i2c_address;
15 };
16 
17 struct eeprom_reply_data {
18 	struct ethnl_reply_data base;
19 	u32			length;
20 	u8			*data;
21 };
22 
23 #define MODULE_EEPROM_REQINFO(__req_base) \
24 	container_of(__req_base, struct eeprom_req_info, base)
25 
26 #define MODULE_EEPROM_REPDATA(__reply_base) \
27 	container_of(__reply_base, struct eeprom_reply_data, base)
28 
29 static int fallback_set_params(struct eeprom_req_info *request,
30 			       struct ethtool_modinfo *modinfo,
31 			       struct ethtool_eeprom *eeprom)
32 {
33 	u32 offset = request->offset;
34 	u32 length = request->length;
35 
36 	if (request->page)
37 		offset = request->page * ETH_MODULE_EEPROM_PAGE_LEN + offset;
38 
39 	if (modinfo->type == ETH_MODULE_SFF_8472 &&
40 	    request->i2c_address == 0x51)
41 		offset += ETH_MODULE_EEPROM_PAGE_LEN * 2;
42 
43 	if (offset >= modinfo->eeprom_len)
44 		return -EINVAL;
45 
46 	eeprom->cmd = ETHTOOL_GMODULEEEPROM;
47 	eeprom->len = length;
48 	eeprom->offset = offset;
49 
50 	return 0;
51 }
52 
53 static int eeprom_fallback(struct eeprom_req_info *request,
54 			   struct eeprom_reply_data *reply)
55 {
56 	struct net_device *dev = reply->base.dev;
57 	struct ethtool_modinfo modinfo = {0};
58 	struct ethtool_eeprom eeprom = {0};
59 	u8 *data;
60 	int err;
61 
62 	modinfo.cmd = ETHTOOL_GMODULEINFO;
63 	err = ethtool_get_module_info_call(dev, &modinfo);
64 	if (err < 0)
65 		return err;
66 
67 	err = fallback_set_params(request, &modinfo, &eeprom);
68 	if (err < 0)
69 		return err;
70 
71 	data = kmalloc(eeprom.len, GFP_KERNEL);
72 	if (!data)
73 		return -ENOMEM;
74 	err = ethtool_get_module_eeprom_call(dev, &eeprom, data);
75 	if (err < 0)
76 		goto err_out;
77 
78 	reply->data = data;
79 	reply->length = eeprom.len;
80 
81 	return 0;
82 
83 err_out:
84 	kfree(data);
85 	return err;
86 }
87 
88 static int get_module_eeprom_by_page(struct net_device *dev,
89 				     struct ethtool_module_eeprom *page_data,
90 				     struct netlink_ext_ack *extack)
91 {
92 	const struct ethtool_ops *ops = dev->ethtool_ops;
93 
94 	if (dev->sfp_bus)
95 		return sfp_get_module_eeprom_by_page(dev->sfp_bus, page_data, extack);
96 
97 	if (ops->get_module_eeprom_by_page)
98 		return ops->get_module_eeprom_by_page(dev, page_data, extack);
99 
100 	return -EOPNOTSUPP;
101 }
102 
103 static int eeprom_prepare_data(const struct ethnl_req_info *req_base,
104 			       struct ethnl_reply_data *reply_base,
105 			       const struct genl_info *info)
106 {
107 	struct eeprom_reply_data *reply = MODULE_EEPROM_REPDATA(reply_base);
108 	struct eeprom_req_info *request = MODULE_EEPROM_REQINFO(req_base);
109 	struct ethtool_module_eeprom page_data = {0};
110 	struct net_device *dev = reply_base->dev;
111 	int ret;
112 
113 	page_data.offset = request->offset;
114 	page_data.length = request->length;
115 	page_data.i2c_address = request->i2c_address;
116 	page_data.page = request->page;
117 	page_data.bank = request->bank;
118 	page_data.data = kmalloc(page_data.length, GFP_KERNEL);
119 	if (!page_data.data)
120 		return -ENOMEM;
121 
122 	ret = ethnl_ops_begin(dev);
123 	if (ret)
124 		goto err_free;
125 
126 	ret = get_module_eeprom_by_page(dev, &page_data, info->extack);
127 	if (ret < 0)
128 		goto err_ops;
129 
130 	reply->length = ret;
131 	reply->data = page_data.data;
132 
133 	ethnl_ops_complete(dev);
134 	return 0;
135 
136 err_ops:
137 	ethnl_ops_complete(dev);
138 err_free:
139 	kfree(page_data.data);
140 
141 	if (ret == -EOPNOTSUPP)
142 		return eeprom_fallback(request, reply);
143 	return ret;
144 }
145 
146 static int eeprom_parse_request(struct ethnl_req_info *req_info, struct nlattr **tb,
147 				struct netlink_ext_ack *extack)
148 {
149 	struct eeprom_req_info *request = MODULE_EEPROM_REQINFO(req_info);
150 
151 	if (!tb[ETHTOOL_A_MODULE_EEPROM_OFFSET] ||
152 	    !tb[ETHTOOL_A_MODULE_EEPROM_LENGTH] ||
153 	    !tb[ETHTOOL_A_MODULE_EEPROM_PAGE] ||
154 	    !tb[ETHTOOL_A_MODULE_EEPROM_I2C_ADDRESS])
155 		return -EINVAL;
156 
157 	request->i2c_address = nla_get_u8(tb[ETHTOOL_A_MODULE_EEPROM_I2C_ADDRESS]);
158 	request->offset = nla_get_u32(tb[ETHTOOL_A_MODULE_EEPROM_OFFSET]);
159 	request->length = nla_get_u32(tb[ETHTOOL_A_MODULE_EEPROM_LENGTH]);
160 
161 	/* The following set of conditions limit the API to only dump 1/2
162 	 * EEPROM page without crossing low page boundary located at offset 128.
163 	 * This means user may only request dumps of length limited to 128 from
164 	 * either low 128 bytes or high 128 bytes.
165 	 * For pages higher than 0 only high 128 bytes are accessible.
166 	 */
167 	request->page = nla_get_u8(tb[ETHTOOL_A_MODULE_EEPROM_PAGE]);
168 	if (request->page && request->offset < ETH_MODULE_EEPROM_PAGE_LEN) {
169 		NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_MODULE_EEPROM_PAGE],
170 				    "reading from lower half page is allowed for page 0 only");
171 		return -EINVAL;
172 	}
173 
174 	if (request->offset < ETH_MODULE_EEPROM_PAGE_LEN &&
175 	    request->offset + request->length > ETH_MODULE_EEPROM_PAGE_LEN) {
176 		NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_MODULE_EEPROM_LENGTH],
177 				    "reading cross half page boundary is illegal");
178 		return -EINVAL;
179 	} else if (request->offset + request->length > ETH_MODULE_EEPROM_PAGE_LEN * 2) {
180 		NL_SET_ERR_MSG_ATTR(extack, tb[ETHTOOL_A_MODULE_EEPROM_LENGTH],
181 				    "reading cross page boundary is illegal");
182 		return -EINVAL;
183 	}
184 
185 	if (tb[ETHTOOL_A_MODULE_EEPROM_BANK])
186 		request->bank = nla_get_u8(tb[ETHTOOL_A_MODULE_EEPROM_BANK]);
187 
188 	return 0;
189 }
190 
191 static int eeprom_reply_size(const struct ethnl_req_info *req_base,
192 			     const struct ethnl_reply_data *reply_base)
193 {
194 	const struct eeprom_req_info *request = MODULE_EEPROM_REQINFO(req_base);
195 
196 	return nla_total_size(sizeof(u8) * request->length); /* _EEPROM_DATA */
197 }
198 
199 static int eeprom_fill_reply(struct sk_buff *skb,
200 			     const struct ethnl_req_info *req_base,
201 			     const struct ethnl_reply_data *reply_base)
202 {
203 	struct eeprom_reply_data *reply = MODULE_EEPROM_REPDATA(reply_base);
204 
205 	return nla_put(skb, ETHTOOL_A_MODULE_EEPROM_DATA, reply->length, reply->data);
206 }
207 
208 static void eeprom_cleanup_data(struct ethnl_reply_data *reply_base)
209 {
210 	struct eeprom_reply_data *reply = MODULE_EEPROM_REPDATA(reply_base);
211 
212 	kfree(reply->data);
213 }
214 
215 const struct ethnl_request_ops ethnl_module_eeprom_request_ops = {
216 	.request_cmd		= ETHTOOL_MSG_MODULE_EEPROM_GET,
217 	.reply_cmd		= ETHTOOL_MSG_MODULE_EEPROM_GET_REPLY,
218 	.hdr_attr		= ETHTOOL_A_MODULE_EEPROM_HEADER,
219 	.req_info_size		= sizeof(struct eeprom_req_info),
220 	.reply_data_size	= sizeof(struct eeprom_reply_data),
221 
222 	.parse_request		= eeprom_parse_request,
223 	.prepare_data		= eeprom_prepare_data,
224 	.reply_size		= eeprom_reply_size,
225 	.fill_reply		= eeprom_fill_reply,
226 	.cleanup_data		= eeprom_cleanup_data,
227 };
228 
229 const struct nla_policy ethnl_module_eeprom_get_policy[] = {
230 	[ETHTOOL_A_MODULE_EEPROM_HEADER]	= NLA_POLICY_NESTED(ethnl_header_policy),
231 	[ETHTOOL_A_MODULE_EEPROM_OFFSET]	=
232 		NLA_POLICY_MAX(NLA_U32, ETH_MODULE_EEPROM_PAGE_LEN * 2 - 1),
233 	[ETHTOOL_A_MODULE_EEPROM_LENGTH]	=
234 		NLA_POLICY_RANGE(NLA_U32, 1, ETH_MODULE_EEPROM_PAGE_LEN),
235 	[ETHTOOL_A_MODULE_EEPROM_PAGE]		= { .type = NLA_U8 },
236 	[ETHTOOL_A_MODULE_EEPROM_BANK]		= { .type = NLA_U8 },
237 	[ETHTOOL_A_MODULE_EEPROM_I2C_ADDRESS]	=
238 		NLA_POLICY_RANGE(NLA_U8, 0, ETH_MODULE_MAX_I2C_ADDRESS),
239 };
240 
241