net/ethtool/channels.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2
   3 #include <net/xdp_sock_drv.h>
   4
   5 #include "netlink.h"
   6 #include "common.h"
   7
   8 struct channels_req_info {
   9         struct ethnl_req_info           base;
  10 };
  11
  12 struct channels_reply_data {
  13         struct ethnl_reply_data         base;
  14         struct ethtool_channels         channels;
  15 };
  16
  17 #define CHANNELS_REPDATA(__reply_base) \
  18         container_of(__reply_base, struct channels_reply_data, base)
  19
  20 const struct nla_policy ethnl_channels_get_policy[] = {
  21         [ETHTOOL_A_CHANNELS_HEADER]             =
  22                 NLA_POLICY_NESTED(ethnl_header_policy),
  23 };
  24
  25 static int channels_prepare_data(const struct ethnl_req_info *req_base,
  26                                  struct ethnl_reply_data *reply_base,
  27                                  const struct genl_info *info)
  28 {
  29         struct channels_reply_data *data = CHANNELS_REPDATA(reply_base);
  30         struct net_device *dev = reply_base->dev;
  31         int ret;
  32
  33         if (!dev->ethtool_ops->get_channels)
  34                 return -EOPNOTSUPP;
  35         ret = ethnl_ops_begin(dev);
  36         if (ret < 0)
  37                 return ret;
  38         dev->ethtool_ops->get_channels(dev, &data->channels);
  39         ethnl_ops_complete(dev);
  40
  41         return 0;
  42 }
  43
  44 static int channels_reply_size(const struct ethnl_req_info *req_base,
  45                                const struct ethnl_reply_data *reply_base)
  46 {
  47         return nla_total_size(sizeof(u32)) +    /* _CHANNELS_RX_MAX */
  48                nla_total_size(sizeof(u32)) +    /* _CHANNELS_TX_MAX */
  49                nla_total_size(sizeof(u32)) +    /* _CHANNELS_OTHER_MAX */
  50                nla_total_size(sizeof(u32)) +    /* _CHANNELS_COMBINED_MAX */
  51                nla_total_size(sizeof(u32)) +    /* _CHANNELS_RX_COUNT */
  52                nla_total_size(sizeof(u32)) +    /* _CHANNELS_TX_COUNT */
  53                nla_total_size(sizeof(u32)) +    /* _CHANNELS_OTHER_COUNT */
  54                nla_total_size(sizeof(u32));     /* _CHANNELS_COMBINED_COUNT */
  55 }
  56
  57 static int channels_fill_reply(struct sk_buff *skb,
  58                                const struct ethnl_req_info *req_base,
  59                                const struct ethnl_reply_data *reply_base)
  60 {
  61         const struct channels_reply_data *data = CHANNELS_REPDATA(reply_base);
  62         const struct ethtool_channels *channels = &data->channels;
  63
  64         if ((channels->max_rx &&
  65              (nla_put_u32(skb, ETHTOOL_A_CHANNELS_RX_MAX,
  66                           channels->max_rx) ||
  67               nla_put_u32(skb, ETHTOOL_A_CHANNELS_RX_COUNT,
  68                           channels->rx_count))) ||
  69             (channels->max_tx &&
  70              (nla_put_u32(skb, ETHTOOL_A_CHANNELS_TX_MAX,
  71                           channels->max_tx) ||
  72               nla_put_u32(skb, ETHTOOL_A_CHANNELS_TX_COUNT,
  73                           channels->tx_count))) ||
  74             (channels->max_other &&
  75              (nla_put_u32(skb, ETHTOOL_A_CHANNELS_OTHER_MAX,
  76                           channels->max_other) ||
  77               nla_put_u32(skb, ETHTOOL_A_CHANNELS_OTHER_COUNT,
  78                           channels->other_count))) ||
  79             (channels->max_combined &&
  80              (nla_put_u32(skb, ETHTOOL_A_CHANNELS_COMBINED_MAX,
  81                           channels->max_combined) ||
  82               nla_put_u32(skb, ETHTOOL_A_CHANNELS_COMBINED_COUNT,
  83                           channels->combined_count))))
  84                 return -EMSGSIZE;
  85
  86         return 0;
  87 }
  88
  89 /* CHANNELS_SET */
  90
  91 const struct nla_policy ethnl_channels_set_policy[] = {
  92         [ETHTOOL_A_CHANNELS_HEADER]             =
  93                 NLA_POLICY_NESTED(ethnl_header_policy),
  94         [ETHTOOL_A_CHANNELS_RX_COUNT]           = { .type = NLA_U32 },
  95         [ETHTOOL_A_CHANNELS_TX_COUNT]           = { .type = NLA_U32 },
  96         [ETHTOOL_A_CHANNELS_OTHER_COUNT]        = { .type = NLA_U32 },
  97         [ETHTOOL_A_CHANNELS_COMBINED_COUNT]     = { .type = NLA_U32 },
  98 };
  99
 100 static int
 101 ethnl_set_channels_validate(struct ethnl_req_info *req_info,
 102                             struct genl_info *info)
 103 {
 104         const struct ethtool_ops *ops = req_info->dev->ethtool_ops;
 105
 106         return ops->get_channels && ops->set_channels ? 1 : -EOPNOTSUPP;
 107 }
 108
 109 static int
 110 ethnl_set_channels(struct ethnl_req_info *req_info, struct genl_info *info)
 111 {
 112         unsigned int from_channel, old_total, i;
 113         bool mod = false, mod_combined = false;
 114         struct net_device *dev = req_info->dev;
 115         struct ethtool_channels channels = {};
 116         struct nlattr **tb = info->attrs;
 117         u32 err_attr;
 118         int ret;
 119
 120         dev->ethtool_ops->get_channels(dev, &channels);
 121         old_total = channels.combined_count +
 122                     max(channels.rx_count, channels.tx_count);
 123
 124         ethnl_update_u32(&channels.rx_count, tb[ETHTOOL_A_CHANNELS_RX_COUNT],
 125                          &mod);
 126         ethnl_update_u32(&channels.tx_count, tb[ETHTOOL_A_CHANNELS_TX_COUNT],
 127                          &mod);
 128         ethnl_update_u32(&channels.other_count,
 129                          tb[ETHTOOL_A_CHANNELS_OTHER_COUNT], &mod);
 130         ethnl_update_u32(&channels.combined_count,
 131                          tb[ETHTOOL_A_CHANNELS_COMBINED_COUNT], &mod_combined);
 132         mod |= mod_combined;
 133         if (!mod)
 134                 return 0;
 135
 136         /* ensure new channel counts are within limits */
 137         if (channels.rx_count > channels.max_rx)
 138                 err_attr = ETHTOOL_A_CHANNELS_RX_COUNT;
 139         else if (channels.tx_count > channels.max_tx)
 140                 err_attr = ETHTOOL_A_CHANNELS_TX_COUNT;
 141         else if (channels.other_count > channels.max_other)
 142                 err_attr = ETHTOOL_A_CHANNELS_OTHER_COUNT;
 143         else if (channels.combined_count > channels.max_combined)
 144                 err_attr = ETHTOOL_A_CHANNELS_COMBINED_COUNT;
 145         else
 146                 err_attr = 0;
 147         if (err_attr) {
 148                 NL_SET_ERR_MSG_ATTR(info->extack, tb[err_attr],
 149                                     "requested channel count exceeds maximum");
 150                 return -EINVAL;
 151         }
 152
 153         /* ensure there is at least one RX and one TX channel */
 154         if (!channels.combined_count && !channels.rx_count)
 155                 err_attr = ETHTOOL_A_CHANNELS_RX_COUNT;
 156         else if (!channels.combined_count && !channels.tx_count)
 157                 err_attr = ETHTOOL_A_CHANNELS_TX_COUNT;
 158         else
 159                 err_attr = 0;
 160         if (err_attr) {
 161                 if (mod_combined)
 162                         err_attr = ETHTOOL_A_CHANNELS_COMBINED_COUNT;
 163                 NL_SET_ERR_MSG_ATTR(info->extack, tb[err_attr],
 164                                     "requested channel counts would result in no RX or TX channel being configured");
 165                 return -EINVAL;
 166         }
 167
 168         ret = ethtool_check_max_channel(dev, channels, info);
 169         if (ret)
 170                 return ret;
 171
 172         /* Disabling channels, query zero-copy AF_XDP sockets */
 173         from_channel = channels.combined_count +
 174                        min(channels.rx_count, channels.tx_count);
 175         for (i = from_channel; i < old_total; i++)
 176                 if (xsk_get_pool_from_qid(dev, i)) {
 177                         GENL_SET_ERR_MSG(info, "requested channel counts are too low for existing zerocopy AF_XDP sockets");
 178                         return -EINVAL;
 179                 }
 180
 181         ret = dev->ethtool_ops->set_channels(dev, &channels);
 182         return ret < 0 ? ret : 1;
 183 }
 184
 185 const struct ethnl_request_ops ethnl_channels_request_ops = {
 186         .request_cmd            = ETHTOOL_MSG_CHANNELS_GET,
 187         .reply_cmd              = ETHTOOL_MSG_CHANNELS_GET_REPLY,
 188         .hdr_attr               = ETHTOOL_A_CHANNELS_HEADER,
 189         .req_info_size          = sizeof(struct channels_req_info),
 190         .reply_data_size        = sizeof(struct channels_reply_data),
 191
 192         .prepare_data           = channels_prepare_data,
 193         .reply_size             = channels_reply_size,
 194         .fill_reply             = channels_fill_reply,
 195
 196         .set_validate           = ethnl_set_channels_validate,
 197         .set                    = ethnl_set_channels,
 198         .set_ntf_cmd            = ETHTOOL_MSG_CHANNELS_NTF,
 199 };