net/ethtool/eeprom.c

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