net/ncsi/ncsi-cmd.c

   1 /*
   2  * Copyright Gavin Shan, IBM Corporation 2016.
   3  *
   4  * This program is free software; you can redistribute it and/or modify
   5  * it under the terms of the GNU General Public License as published by
   6  * the Free Software Foundation; either version 2 of the License, or
   7  * (at your option) any later version.
   8  */
   9
  10 #include <linux/module.h>
  11 #include <linux/kernel.h>
  12 #include <linux/init.h>
  13 #include <linux/etherdevice.h>
  14 #include <linux/netdevice.h>
  15 #include <linux/skbuff.h>
  16
  17 #include <net/ncsi.h>
  18 #include <net/net_namespace.h>
  19 #include <net/sock.h>
  20
  21 #include "internal.h"
  22 #include "ncsi-pkt.h"
  23
  24 u32 ncsi_calculate_checksum(unsigned char *data, int len)
  25 {
  26         u32 checksum = 0;
  27         int i;
  28
  29         for (i = 0; i < len; i += 2)
  30                 checksum += (((u32)data[i] << 8) | data[i + 1]);
  31
  32         checksum = (~checksum + 1);
  33         return checksum;
  34 }
  35
  36 /* This function should be called after the data area has been
  37  * populated completely.
  38  */
  39 static void ncsi_cmd_build_header(struct ncsi_pkt_hdr *h,
  40                                   struct ncsi_cmd_arg *nca)
  41 {
  42         u32 checksum;
  43         __be32 *pchecksum;
  44
  45         h->mc_id        = 0;
  46         h->revision     = NCSI_PKT_REVISION;
  47         h->reserved     = 0;
  48         h->id           = nca->id;
  49         h->type         = nca->type;
  50         h->channel      = NCSI_TO_CHANNEL(nca->package,
  51                                           nca->channel);
  52         h->length       = htons(nca->payload);
  53         h->reserved1[0] = 0;
  54         h->reserved1[1] = 0;
  55
  56         /* Fill with calculated checksum */
  57         checksum = ncsi_calculate_checksum((unsigned char *)h,
  58                                            sizeof(*h) + nca->payload);
  59         pchecksum = (__be32 *)((void *)h + sizeof(struct ncsi_pkt_hdr) +
  60                     nca->payload);
  61         *pchecksum = htonl(checksum);
  62 }
  63
  64 static int ncsi_cmd_handler_default(struct sk_buff *skb,
  65                                     struct ncsi_cmd_arg *nca)
  66 {
  67         struct ncsi_cmd_pkt *cmd;
  68
  69         cmd = skb_put_zero(skb, sizeof(*cmd));
  70         ncsi_cmd_build_header(&cmd->cmd.common, nca);
  71
  72         return 0;
  73 }
  74
  75 static int ncsi_cmd_handler_sp(struct sk_buff *skb,
  76                                struct ncsi_cmd_arg *nca)
  77 {
  78         struct ncsi_cmd_sp_pkt *cmd;
  79
  80         cmd = skb_put_zero(skb, sizeof(*cmd));
  81         cmd->hw_arbitration = nca->bytes[0];
  82         ncsi_cmd_build_header(&cmd->cmd.common, nca);
  83
  84         return 0;
  85 }
  86
  87 static int ncsi_cmd_handler_dc(struct sk_buff *skb,
  88                                struct ncsi_cmd_arg *nca)
  89 {
  90         struct ncsi_cmd_dc_pkt *cmd;
  91
  92         cmd = skb_put_zero(skb, sizeof(*cmd));
  93         cmd->ald = nca->bytes[0];
  94         ncsi_cmd_build_header(&cmd->cmd.common, nca);
  95
  96         return 0;
  97 }
  98
  99 static int ncsi_cmd_handler_rc(struct sk_buff *skb,
 100                                struct ncsi_cmd_arg *nca)
 101 {
 102         struct ncsi_cmd_rc_pkt *cmd;
 103
 104         cmd = skb_put_zero(skb, sizeof(*cmd));
 105         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 106
 107         return 0;
 108 }
 109
 110 static int ncsi_cmd_handler_ae(struct sk_buff *skb,
 111                                struct ncsi_cmd_arg *nca)
 112 {
 113         struct ncsi_cmd_ae_pkt *cmd;
 114
 115         cmd = skb_put_zero(skb, sizeof(*cmd));
 116         cmd->mc_id = nca->bytes[0];
 117         cmd->mode = htonl(nca->dwords[1]);
 118         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 119
 120         return 0;
 121 }
 122
 123 static int ncsi_cmd_handler_sl(struct sk_buff *skb,
 124                                struct ncsi_cmd_arg *nca)
 125 {
 126         struct ncsi_cmd_sl_pkt *cmd;
 127
 128         cmd = skb_put_zero(skb, sizeof(*cmd));
 129         cmd->mode = htonl(nca->dwords[0]);
 130         cmd->oem_mode = htonl(nca->dwords[1]);
 131         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 132
 133         return 0;
 134 }
 135
 136 static int ncsi_cmd_handler_svf(struct sk_buff *skb,
 137                                 struct ncsi_cmd_arg *nca)
 138 {
 139         struct ncsi_cmd_svf_pkt *cmd;
 140
 141         cmd = skb_put_zero(skb, sizeof(*cmd));
 142         cmd->vlan = htons(nca->words[1]);
 143         cmd->index = nca->bytes[6];
 144         cmd->enable = nca->bytes[7];
 145         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 146
 147         return 0;
 148 }
 149
 150 static int ncsi_cmd_handler_ev(struct sk_buff *skb,
 151                                struct ncsi_cmd_arg *nca)
 152 {
 153         struct ncsi_cmd_ev_pkt *cmd;
 154
 155         cmd = skb_put_zero(skb, sizeof(*cmd));
 156         cmd->mode = nca->bytes[3];
 157         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 158
 159         return 0;
 160 }
 161
 162 static int ncsi_cmd_handler_sma(struct sk_buff *skb,
 163                                 struct ncsi_cmd_arg *nca)
 164 {
 165         struct ncsi_cmd_sma_pkt *cmd;
 166         int i;
 167
 168         cmd = skb_put_zero(skb, sizeof(*cmd));
 169         for (i = 0; i < 6; i++)
 170                 cmd->mac[i] = nca->bytes[i];
 171         cmd->index = nca->bytes[6];
 172         cmd->at_e = nca->bytes[7];
 173         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 174
 175         return 0;
 176 }
 177
 178 static int ncsi_cmd_handler_ebf(struct sk_buff *skb,
 179                                 struct ncsi_cmd_arg *nca)
 180 {
 181         struct ncsi_cmd_ebf_pkt *cmd;
 182
 183         cmd = skb_put_zero(skb, sizeof(*cmd));
 184         cmd->mode = htonl(nca->dwords[0]);
 185         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 186
 187         return 0;
 188 }
 189
 190 static int ncsi_cmd_handler_egmf(struct sk_buff *skb,
 191                                  struct ncsi_cmd_arg *nca)
 192 {
 193         struct ncsi_cmd_egmf_pkt *cmd;
 194
 195         cmd = skb_put_zero(skb, sizeof(*cmd));
 196         cmd->mode = htonl(nca->dwords[0]);
 197         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 198
 199         return 0;
 200 }
 201
 202 static int ncsi_cmd_handler_snfc(struct sk_buff *skb,
 203                                  struct ncsi_cmd_arg *nca)
 204 {
 205         struct ncsi_cmd_snfc_pkt *cmd;
 206
 207         cmd = skb_put_zero(skb, sizeof(*cmd));
 208         cmd->mode = nca->bytes[0];
 209         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 210
 211         return 0;
 212 }
 213
 214 static struct ncsi_cmd_handler {
 215         unsigned char type;
 216         int           payload;
 217         int           (*handler)(struct sk_buff *skb,
 218                                  struct ncsi_cmd_arg *nca);
 219 } ncsi_cmd_handlers[] = {
 220         { NCSI_PKT_CMD_CIS,    0, ncsi_cmd_handler_default },
 221         { NCSI_PKT_CMD_SP,     4, ncsi_cmd_handler_sp      },
 222         { NCSI_PKT_CMD_DP,     0, ncsi_cmd_handler_default },
 223         { NCSI_PKT_CMD_EC,     0, ncsi_cmd_handler_default },
 224         { NCSI_PKT_CMD_DC,     4, ncsi_cmd_handler_dc      },
 225         { NCSI_PKT_CMD_RC,     4, ncsi_cmd_handler_rc      },
 226         { NCSI_PKT_CMD_ECNT,   0, ncsi_cmd_handler_default },
 227         { NCSI_PKT_CMD_DCNT,   0, ncsi_cmd_handler_default },
 228         { NCSI_PKT_CMD_AE,     8, ncsi_cmd_handler_ae      },
 229         { NCSI_PKT_CMD_SL,     8, ncsi_cmd_handler_sl      },
 230         { NCSI_PKT_CMD_GLS,    0, ncsi_cmd_handler_default },
 231         { NCSI_PKT_CMD_SVF,    8, ncsi_cmd_handler_svf     },
 232         { NCSI_PKT_CMD_EV,     4, ncsi_cmd_handler_ev      },
 233         { NCSI_PKT_CMD_DV,     0, ncsi_cmd_handler_default },
 234         { NCSI_PKT_CMD_SMA,    8, ncsi_cmd_handler_sma     },
 235         { NCSI_PKT_CMD_EBF,    4, ncsi_cmd_handler_ebf     },
 236         { NCSI_PKT_CMD_DBF,    0, ncsi_cmd_handler_default },
 237         { NCSI_PKT_CMD_EGMF,   4, ncsi_cmd_handler_egmf    },
 238         { NCSI_PKT_CMD_DGMF,   0, ncsi_cmd_handler_default },
 239         { NCSI_PKT_CMD_SNFC,   4, ncsi_cmd_handler_snfc    },
 240         { NCSI_PKT_CMD_GVI,    0, ncsi_cmd_handler_default },
 241         { NCSI_PKT_CMD_GC,     0, ncsi_cmd_handler_default },
 242         { NCSI_PKT_CMD_GP,     0, ncsi_cmd_handler_default },
 243         { NCSI_PKT_CMD_GCPS,   0, ncsi_cmd_handler_default },
 244         { NCSI_PKT_CMD_GNS,    0, ncsi_cmd_handler_default },
 245         { NCSI_PKT_CMD_GNPTS,  0, ncsi_cmd_handler_default },
 246         { NCSI_PKT_CMD_GPS,    0, ncsi_cmd_handler_default },
 247         { NCSI_PKT_CMD_OEM,    0, NULL                     },
 248         { NCSI_PKT_CMD_PLDM,   0, NULL                     },
 249         { NCSI_PKT_CMD_GPUUID, 0, ncsi_cmd_handler_default }
 250 };
 251
 252 static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca)
 253 {
 254         struct ncsi_dev_priv *ndp = nca->ndp;
 255         struct ncsi_dev *nd = &ndp->ndev;
 256         struct net_device *dev = nd->dev;
 257         int hlen = LL_RESERVED_SPACE(dev);
 258         int tlen = dev->needed_tailroom;
 259         int len = hlen + tlen;
 260         struct sk_buff *skb;
 261         struct ncsi_request *nr;
 262
 263         nr = ncsi_alloc_request(ndp, nca->req_flags);
 264         if (!nr)
 265                 return NULL;
 266
 267         /* NCSI command packet has 16-bytes header, payload, 4 bytes checksum.
 268          * The packet needs padding if its payload is less than 26 bytes to
 269          * meet 64 bytes minimal ethernet frame length.
 270          */
 271         len += sizeof(struct ncsi_cmd_pkt_hdr) + 4;
 272         if (nca->payload < 26)
 273                 len += 26;
 274         else
 275                 len += nca->payload;
 276
 277         /* Allocate skb */
 278         skb = alloc_skb(len, GFP_ATOMIC);
 279         if (!skb) {
 280                 ncsi_free_request(nr);
 281                 return NULL;
 282         }
 283
 284         nr->cmd = skb;
 285         skb_reserve(skb, hlen);
 286         skb_reset_network_header(skb);
 287
 288         skb->dev = dev;
 289         skb->protocol = htons(ETH_P_NCSI);
 290
 291         return nr;
 292 }
 293
 294 int ncsi_xmit_cmd(struct ncsi_cmd_arg *nca)
 295 {
 296         struct ncsi_request *nr;
 297         struct ethhdr *eh;
 298         struct ncsi_cmd_handler *nch = NULL;
 299         int i, ret;
 300
 301         /* Search for the handler */
 302         for (i = 0; i < ARRAY_SIZE(ncsi_cmd_handlers); i++) {
 303                 if (ncsi_cmd_handlers[i].type == nca->type) {
 304                         if (ncsi_cmd_handlers[i].handler)
 305                                 nch = &ncsi_cmd_handlers[i];
 306                         else
 307                                 nch = NULL;
 308
 309                         break;
 310                 }
 311         }
 312
 313         if (!nch) {
 314                 netdev_err(nca->ndp->ndev.dev,
 315                            "Cannot send packet with type 0x%02x\n", nca->type);
 316                 return -ENOENT;
 317         }
 318
 319         /* Get packet payload length and allocate the request */
 320         nca->payload = nch->payload;
 321         nr = ncsi_alloc_command(nca);
 322         if (!nr)
 323                 return -ENOMEM;
 324
 325         /* Prepare the packet */
 326         nca->id = nr->id;
 327         ret = nch->handler(nr->cmd, nca);
 328         if (ret) {
 329                 ncsi_free_request(nr);
 330                 return ret;
 331         }
 332
 333         /* Fill the ethernet header */
 334         eh = skb_push(nr->cmd, sizeof(*eh));
 335         eh->h_proto = htons(ETH_P_NCSI);
 336         eth_broadcast_addr(eh->h_dest);
 337         eth_broadcast_addr(eh->h_source);
 338
 339         /* Start the timer for the request that might not have
 340          * corresponding response. Given NCSI is an internal
 341          * connection a 1 second delay should be sufficient.
 342          */
 343         nr->enabled = true;
 344         mod_timer(&nr->timer, jiffies + 1 * HZ);
 345
 346         /* Send NCSI packet */
 347         skb_get(nr->cmd);
 348         ret = dev_queue_xmit(nr->cmd);
 349         if (ret < 0) {
 350                 ncsi_free_request(nr);
 351                 return ret;
 352         }
 353
 354         return 0;
 355 }