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                                  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 const struct ethnl_request_ops ethnl_channels_request_ops = {
  90         .request_cmd            = ETHTOOL_MSG_CHANNELS_GET,
  91         .reply_cmd              = ETHTOOL_MSG_CHANNELS_GET_REPLY,
  92         .hdr_attr               = ETHTOOL_A_CHANNELS_HEADER,
  93         .req_info_size          = sizeof(struct channels_req_info),
  94         .reply_data_size        = sizeof(struct channels_reply_data),
  95
  96         .prepare_data           = channels_prepare_data,
  97         .reply_size             = channels_reply_size,
  98         .fill_reply             = channels_fill_reply,
  99 };
 100
 101 /* CHANNELS_SET */
 102
 103 const struct nla_policy ethnl_channels_set_policy[] = {
 104         [ETHTOOL_A_CHANNELS_HEADER]             =
 105                 NLA_POLICY_NESTED(ethnl_header_policy),
 106         [ETHTOOL_A_CHANNELS_RX_COUNT]           = { .type = NLA_U32 },
 107         [ETHTOOL_A_CHANNELS_TX_COUNT]           = { .type = NLA_U32 },
 108         [ETHTOOL_A_CHANNELS_OTHER_COUNT]        = { .type = NLA_U32 },
 109         [ETHTOOL_A_CHANNELS_COMBINED_COUNT]     = { .type = NLA_U32 },
 110 };
 111
 112 int ethnl_set_channels(struct sk_buff *skb, struct genl_info *info)
 113 {
 114         unsigned int from_channel, old_total, i;
 115         bool mod = false, mod_combined = false;
 116         struct ethtool_channels channels = {};
 117         struct ethnl_req_info req_info = {};
 118         struct nlattr **tb = info->attrs;
 119         const struct nlattr *err_attr;
 120         const struct ethtool_ops *ops;
 121         struct net_device *dev;
 122         u32 max_rx_in_use = 0;
 123         int ret;
 124
 125         ret = ethnl_parse_header_dev_get(&req_info,
 126                                          tb[ETHTOOL_A_CHANNELS_HEADER],
 127                                          genl_info_net(info), info->extack,
 128                                          true);
 129         if (ret < 0)
 130                 return ret;
 131         dev = req_info.dev;
 132         ops = dev->ethtool_ops;
 133         ret = -EOPNOTSUPP;
 134         if (!ops->get_channels || !ops->set_channels)
 135                 goto out_dev;
 136
 137         rtnl_lock();
 138         ret = ethnl_ops_begin(dev);
 139         if (ret < 0)
 140                 goto out_rtnl;
 141         ops->get_channels(dev, &channels);
 142         old_total = channels.combined_count +
 143                     max(channels.rx_count, channels.tx_count);
 144
 145         ethnl_update_u32(&channels.rx_count, tb[ETHTOOL_A_CHANNELS_RX_COUNT],
 146                          &mod);
 147         ethnl_update_u32(&channels.tx_count, tb[ETHTOOL_A_CHANNELS_TX_COUNT],
 148                          &mod);
 149         ethnl_update_u32(&channels.other_count,
 150                          tb[ETHTOOL_A_CHANNELS_OTHER_COUNT], &mod);
 151         ethnl_update_u32(&channels.combined_count,
 152                          tb[ETHTOOL_A_CHANNELS_COMBINED_COUNT], &mod_combined);
 153         mod |= mod_combined;
 154         ret = 0;
 155         if (!mod)
 156                 goto out_ops;
 157
 158         /* ensure new channel counts are within limits */
 159         if (channels.rx_count > channels.max_rx)
 160                 err_attr = tb[ETHTOOL_A_CHANNELS_RX_COUNT];
 161         else if (channels.tx_count > channels.max_tx)
 162                 err_attr = tb[ETHTOOL_A_CHANNELS_TX_COUNT];
 163         else if (channels.other_count > channels.max_other)
 164                 err_attr = tb[ETHTOOL_A_CHANNELS_OTHER_COUNT];
 165         else if (channels.combined_count > channels.max_combined)
 166                 err_attr = tb[ETHTOOL_A_CHANNELS_COMBINED_COUNT];
 167         else
 168                 err_attr = NULL;
 169         if (err_attr) {
 170                 ret = -EINVAL;
 171                 NL_SET_ERR_MSG_ATTR(info->extack, err_attr,
 172                                     "requested channel count exceeds maximum");
 173                 goto out_ops;
 174         }
 175
 176         /* ensure there is at least one RX and one TX channel */
 177         if (!channels.combined_count && !channels.rx_count)
 178                 err_attr = tb[ETHTOOL_A_CHANNELS_RX_COUNT];
 179         else if (!channels.combined_count && !channels.tx_count)
 180                 err_attr = tb[ETHTOOL_A_CHANNELS_TX_COUNT];
 181         else
 182                 err_attr = NULL;
 183         if (err_attr) {
 184                 if (mod_combined)
 185                         err_attr = tb[ETHTOOL_A_CHANNELS_COMBINED_COUNT];
 186                 ret = -EINVAL;
 187                 NL_SET_ERR_MSG_ATTR(info->extack, err_attr, "requested channel counts would result in no RX or TX channel being configured");
 188                 goto out_ops;
 189         }
 190
 191         /* ensure the new Rx count fits within the configured Rx flow
 192          * indirection table settings
 193          */
 194         if (netif_is_rxfh_configured(dev) &&
 195             !ethtool_get_max_rxfh_channel(dev, &max_rx_in_use) &&
 196             (channels.combined_count + channels.rx_count) <= max_rx_in_use) {
 197                 ret = -EINVAL;
 198                 GENL_SET_ERR_MSG(info, "requested channel counts are too low for existing indirection table settings");
 199                 goto out_ops;
 200         }
 201
 202         /* Disabling channels, query zero-copy AF_XDP sockets */
 203         from_channel = channels.combined_count +
 204                        min(channels.rx_count, channels.tx_count);
 205         for (i = from_channel; i < old_total; i++)
 206                 if (xsk_get_pool_from_qid(dev, i)) {
 207                         ret = -EINVAL;
 208                         GENL_SET_ERR_MSG(info, "requested channel counts are too low for existing zerocopy AF_XDP sockets");
 209                         goto out_ops;
 210                 }
 211
 212         ret = dev->ethtool_ops->set_channels(dev, &channels);
 213         if (ret < 0)
 214                 goto out_ops;
 215         ethtool_notify(dev, ETHTOOL_MSG_CHANNELS_NTF, NULL);
 216
 217 out_ops:
 218         ethnl_ops_complete(dev);
 219 out_rtnl:
 220         rtnl_unlock();
 221 out_dev:
 222         dev_put(dev);
 223         return ret;
 224 }