net/ncsi/ncsi-cmd.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright Gavin Shan, IBM Corporation 2016.
   4  */
   5
   6 #include <linux/module.h>
   7 #include <linux/kernel.h>
   8 #include <linux/init.h>
   9 #include <linux/etherdevice.h>
  10 #include <linux/netdevice.h>
  11 #include <linux/skbuff.h>
  12
  13 #include <net/ncsi.h>
  14 #include <net/net_namespace.h>
  15 #include <net/sock.h>
  16 #include <net/genetlink.h>
  17
  18 #include "internal.h"
  19 #include "ncsi-pkt.h"
  20
  21 static const int padding_bytes = 26;
  22
  23 u32 ncsi_calculate_checksum(unsigned char *data, int len)
  24 {
  25         u32 checksum = 0;
  26         int i;
  27
  28         for (i = 0; i < len; i += 2)
  29                 checksum += (((u32)data[i] << 8) | data[i + 1]);
  30
  31         checksum = (~checksum + 1);
  32         return checksum;
  33 }
  34
  35 /* This function should be called after the data area has been
  36  * populated completely.
  37  */
  38 static void ncsi_cmd_build_header(struct ncsi_pkt_hdr *h,
  39                                   struct ncsi_cmd_arg *nca)
  40 {
  41         u32 checksum;
  42         __be32 *pchecksum;
  43
  44         h->mc_id        = 0;
  45         h->revision     = NCSI_PKT_REVISION;
  46         h->reserved     = 0;
  47         h->id           = nca->id;
  48         h->type         = nca->type;
  49         h->channel      = NCSI_TO_CHANNEL(nca->package,
  50                                           nca->channel);
  51         h->length       = htons(nca->payload);
  52         h->reserved1[0] = 0;
  53         h->reserved1[1] = 0;
  54
  55         /* Fill with calculated checksum */
  56         checksum = ncsi_calculate_checksum((unsigned char *)h,
  57                                            sizeof(*h) + nca->payload);
  58         pchecksum = (__be32 *)((void *)h + sizeof(struct ncsi_pkt_hdr) +
  59                     ALIGN(nca->payload, 4));
  60         *pchecksum = htonl(checksum);
  61 }
  62
  63 static int ncsi_cmd_handler_default(struct sk_buff *skb,
  64                                     struct ncsi_cmd_arg *nca)
  65 {
  66         struct ncsi_cmd_pkt *cmd;
  67
  68         cmd = skb_put_zero(skb, sizeof(*cmd));
  69         ncsi_cmd_build_header(&cmd->cmd.common, nca);
  70
  71         return 0;
  72 }
  73
  74 static int ncsi_cmd_handler_sp(struct sk_buff *skb,
  75                                struct ncsi_cmd_arg *nca)
  76 {
  77         struct ncsi_cmd_sp_pkt *cmd;
  78
  79         cmd = skb_put_zero(skb, sizeof(*cmd));
  80         cmd->hw_arbitration = nca->bytes[0];
  81         ncsi_cmd_build_header(&cmd->cmd.common, nca);
  82
  83         return 0;
  84 }
  85
  86 static int ncsi_cmd_handler_dc(struct sk_buff *skb,
  87                                struct ncsi_cmd_arg *nca)
  88 {
  89         struct ncsi_cmd_dc_pkt *cmd;
  90
  91         cmd = skb_put_zero(skb, sizeof(*cmd));
  92         cmd->ald = nca->bytes[0];
  93         ncsi_cmd_build_header(&cmd->cmd.common, nca);
  94
  95         return 0;
  96 }
  97
  98 static int ncsi_cmd_handler_rc(struct sk_buff *skb,
  99                                struct ncsi_cmd_arg *nca)
 100 {
 101         struct ncsi_cmd_rc_pkt *cmd;
 102
 103         cmd = skb_put_zero(skb, sizeof(*cmd));
 104         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 105
 106         return 0;
 107 }
 108
 109 static int ncsi_cmd_handler_ae(struct sk_buff *skb,
 110                                struct ncsi_cmd_arg *nca)
 111 {
 112         struct ncsi_cmd_ae_pkt *cmd;
 113
 114         cmd = skb_put_zero(skb, sizeof(*cmd));
 115         cmd->mc_id = nca->bytes[0];
 116         cmd->mode = htonl(nca->dwords[1]);
 117         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 118
 119         return 0;
 120 }
 121
 122 static int ncsi_cmd_handler_sl(struct sk_buff *skb,
 123                                struct ncsi_cmd_arg *nca)
 124 {
 125         struct ncsi_cmd_sl_pkt *cmd;
 126
 127         cmd = skb_put_zero(skb, sizeof(*cmd));
 128         cmd->mode = htonl(nca->dwords[0]);
 129         cmd->oem_mode = htonl(nca->dwords[1]);
 130         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 131
 132         return 0;
 133 }
 134
 135 static int ncsi_cmd_handler_svf(struct sk_buff *skb,
 136                                 struct ncsi_cmd_arg *nca)
 137 {
 138         struct ncsi_cmd_svf_pkt *cmd;
 139
 140         cmd = skb_put_zero(skb, sizeof(*cmd));
 141         cmd->vlan = htons(nca->words[1]);
 142         cmd->index = nca->bytes[6];
 143         cmd->enable = nca->bytes[7];
 144         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 145
 146         return 0;
 147 }
 148
 149 static int ncsi_cmd_handler_ev(struct sk_buff *skb,
 150                                struct ncsi_cmd_arg *nca)
 151 {
 152         struct ncsi_cmd_ev_pkt *cmd;
 153
 154         cmd = skb_put_zero(skb, sizeof(*cmd));
 155         cmd->mode = nca->bytes[3];
 156         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 157
 158         return 0;
 159 }
 160
 161 static int ncsi_cmd_handler_sma(struct sk_buff *skb,
 162                                 struct ncsi_cmd_arg *nca)
 163 {
 164         struct ncsi_cmd_sma_pkt *cmd;
 165         int i;
 166
 167         cmd = skb_put_zero(skb, sizeof(*cmd));
 168         for (i = 0; i < 6; i++)
 169                 cmd->mac[i] = nca->bytes[i];
 170         cmd->index = nca->bytes[6];
 171         cmd->at_e = nca->bytes[7];
 172         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 173
 174         return 0;
 175 }
 176
 177 static int ncsi_cmd_handler_ebf(struct sk_buff *skb,
 178                                 struct ncsi_cmd_arg *nca)
 179 {
 180         struct ncsi_cmd_ebf_pkt *cmd;
 181
 182         cmd = skb_put_zero(skb, sizeof(*cmd));
 183         cmd->mode = htonl(nca->dwords[0]);
 184         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 185
 186         return 0;
 187 }
 188
 189 static int ncsi_cmd_handler_egmf(struct sk_buff *skb,
 190                                  struct ncsi_cmd_arg *nca)
 191 {
 192         struct ncsi_cmd_egmf_pkt *cmd;
 193
 194         cmd = skb_put_zero(skb, sizeof(*cmd));
 195         cmd->mode = htonl(nca->dwords[0]);
 196         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 197
 198         return 0;
 199 }
 200
 201 static int ncsi_cmd_handler_snfc(struct sk_buff *skb,
 202                                  struct ncsi_cmd_arg *nca)
 203 {
 204         struct ncsi_cmd_snfc_pkt *cmd;
 205
 206         cmd = skb_put_zero(skb, sizeof(*cmd));
 207         cmd->mode = nca->bytes[0];
 208         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 209
 210         return 0;
 211 }
 212
 213 static int ncsi_cmd_handler_oem(struct sk_buff *skb,
 214                                 struct ncsi_cmd_arg *nca)
 215 {
 216         struct ncsi_cmd_oem_pkt *cmd;
 217         unsigned int len;
 218         int payload;
 219         /* NC-SI spec DSP_0222_1.2.0, section 8.2.2.2
 220          * requires payload to be padded with 0 to
 221          * 32-bit boundary before the checksum field.
 222          * Ensure the padding bytes are accounted for in
 223          * skb allocation
 224          */
 225
 226         payload = ALIGN(nca->payload, 4);
 227         len = sizeof(struct ncsi_cmd_pkt_hdr) + 4;
 228         len += max(payload, padding_bytes);
 229
 230         cmd = skb_put_zero(skb, len);
 231         unsafe_memcpy(&cmd->mfr_id, nca->data, nca->payload,
 232                       /* skb allocated with enough to load the payload */);
 233         ncsi_cmd_build_header(&cmd->cmd.common, nca);
 234
 235         return 0;
 236 }
 237
 238 static struct ncsi_cmd_handler {
 239         unsigned char type;
 240         int           payload;
 241         int           (*handler)(struct sk_buff *skb,
 242                                  struct ncsi_cmd_arg *nca);
 243 } ncsi_cmd_handlers[] = {
 244         { NCSI_PKT_CMD_CIS,    0, ncsi_cmd_handler_default },
 245         { NCSI_PKT_CMD_SP,     4, ncsi_cmd_handler_sp      },
 246         { NCSI_PKT_CMD_DP,     0, ncsi_cmd_handler_default },
 247         { NCSI_PKT_CMD_EC,     0, ncsi_cmd_handler_default },
 248         { NCSI_PKT_CMD_DC,     4, ncsi_cmd_handler_dc      },
 249         { NCSI_PKT_CMD_RC,     4, ncsi_cmd_handler_rc      },
 250         { NCSI_PKT_CMD_ECNT,   0, ncsi_cmd_handler_default },
 251         { NCSI_PKT_CMD_DCNT,   0, ncsi_cmd_handler_default },
 252         { NCSI_PKT_CMD_AE,     8, ncsi_cmd_handler_ae      },
 253         { NCSI_PKT_CMD_SL,     8, ncsi_cmd_handler_sl      },
 254         { NCSI_PKT_CMD_GLS,    0, ncsi_cmd_handler_default },
 255         { NCSI_PKT_CMD_SVF,    8, ncsi_cmd_handler_svf     },
 256         { NCSI_PKT_CMD_EV,     4, ncsi_cmd_handler_ev      },
 257         { NCSI_PKT_CMD_DV,     0, ncsi_cmd_handler_default },
 258         { NCSI_PKT_CMD_SMA,    8, ncsi_cmd_handler_sma     },
 259         { NCSI_PKT_CMD_EBF,    4, ncsi_cmd_handler_ebf     },
 260         { NCSI_PKT_CMD_DBF,    0, ncsi_cmd_handler_default },
 261         { NCSI_PKT_CMD_EGMF,   4, ncsi_cmd_handler_egmf    },
 262         { NCSI_PKT_CMD_DGMF,   0, ncsi_cmd_handler_default },
 263         { NCSI_PKT_CMD_SNFC,   4, ncsi_cmd_handler_snfc    },
 264         { NCSI_PKT_CMD_GVI,    0, ncsi_cmd_handler_default },
 265         { NCSI_PKT_CMD_GC,     0, ncsi_cmd_handler_default },
 266         { NCSI_PKT_CMD_GP,     0, ncsi_cmd_handler_default },
 267         { NCSI_PKT_CMD_GCPS,   0, ncsi_cmd_handler_default },
 268         { NCSI_PKT_CMD_GNS,    0, ncsi_cmd_handler_default },
 269         { NCSI_PKT_CMD_GNPTS,  0, ncsi_cmd_handler_default },
 270         { NCSI_PKT_CMD_GPS,    0, ncsi_cmd_handler_default },
 271         { NCSI_PKT_CMD_OEM,   -1, ncsi_cmd_handler_oem     },
 272         { NCSI_PKT_CMD_PLDM,   0, NULL                     },
 273         { NCSI_PKT_CMD_GPUUID, 0, ncsi_cmd_handler_default },
 274         { NCSI_PKT_CMD_GMCMA,  0, ncsi_cmd_handler_default }
 275 };
 276
 277 static struct ncsi_request *ncsi_alloc_command(struct ncsi_cmd_arg *nca)
 278 {
 279         struct ncsi_dev_priv *ndp = nca->ndp;
 280         struct ncsi_dev *nd = &ndp->ndev;
 281         struct net_device *dev = nd->dev;
 282         int hlen = LL_RESERVED_SPACE(dev);
 283         int tlen = dev->needed_tailroom;
 284         int payload;
 285         int len = hlen + tlen;
 286         struct sk_buff *skb;
 287         struct ncsi_request *nr;
 288
 289         nr = ncsi_alloc_request(ndp, nca->req_flags);
 290         if (!nr)
 291                 return NULL;
 292
 293         /* NCSI command packet has 16-bytes header, payload, 4 bytes checksum.
 294          * Payload needs padding so that the checksum field following payload is
 295          * aligned to 32-bit boundary.
 296          * The packet needs padding if its payload is less than 26 bytes to
 297          * meet 64 bytes minimal ethernet frame length.
 298          */
 299         len += sizeof(struct ncsi_cmd_pkt_hdr) + 4;
 300         payload = ALIGN(nca->payload, 4);
 301         len += max(payload, padding_bytes);
 302
 303         /* Allocate skb */
 304         skb = alloc_skb(len, GFP_ATOMIC);
 305         if (!skb) {
 306                 ncsi_free_request(nr);
 307                 return NULL;
 308         }
 309
 310         nr->cmd = skb;
 311         skb_reserve(skb, hlen);
 312         skb_reset_network_header(skb);
 313
 314         skb->dev = dev;
 315         skb->protocol = htons(ETH_P_NCSI);
 316
 317         return nr;
 318 }
 319
 320 int ncsi_xmit_cmd(struct ncsi_cmd_arg *nca)
 321 {
 322         struct ncsi_cmd_handler *nch = NULL;
 323         struct ncsi_request *nr;
 324         unsigned char type;
 325         struct ethhdr *eh;
 326         int i, ret;
 327
 328         /* Use OEM generic handler for Netlink request */
 329         if (nca->req_flags == NCSI_REQ_FLAG_NETLINK_DRIVEN)
 330                 type = NCSI_PKT_CMD_OEM;
 331         else
 332                 type = nca->type;
 333
 334         /* Search for the handler */
 335         for (i = 0; i < ARRAY_SIZE(ncsi_cmd_handlers); i++) {
 336                 if (ncsi_cmd_handlers[i].type == type) {
 337                         if (ncsi_cmd_handlers[i].handler)
 338                                 nch = &ncsi_cmd_handlers[i];
 339                         else
 340                                 nch = NULL;
 341
 342                         break;
 343                 }
 344         }
 345
 346         if (!nch) {
 347                 netdev_err(nca->ndp->ndev.dev,
 348                            "Cannot send packet with type 0x%02x\n", nca->type);
 349                 return -ENOENT;
 350         }
 351
 352         /* Get packet payload length and allocate the request
 353          * It is expected that if length set as negative in
 354          * handler structure means caller is initializing it
 355          * and setting length in nca before calling xmit function
 356          */
 357         if (nch->payload >= 0)
 358                 nca->payload = nch->payload;
 359         nr = ncsi_alloc_command(nca);
 360         if (!nr)
 361                 return -ENOMEM;
 362
 363         /* track netlink information */
 364         if (nca->req_flags == NCSI_REQ_FLAG_NETLINK_DRIVEN) {
 365                 nr->snd_seq = nca->info->snd_seq;
 366                 nr->snd_portid = nca->info->snd_portid;
 367                 nr->nlhdr = *nca->info->nlhdr;
 368         }
 369
 370         /* Prepare the packet */
 371         nca->id = nr->id;
 372         ret = nch->handler(nr->cmd, nca);
 373         if (ret) {
 374                 ncsi_free_request(nr);
 375                 return ret;
 376         }
 377
 378         /* Fill the ethernet header */
 379         eh = skb_push(nr->cmd, sizeof(*eh));
 380         eh->h_proto = htons(ETH_P_NCSI);
 381         eth_broadcast_addr(eh->h_dest);
 382
 383         /* If mac address received from device then use it for
 384          * source address as unicast address else use broadcast
 385          * address as source address
 386          */
 387         if (nca->ndp->gma_flag == 1)
 388                 memcpy(eh->h_source, nca->ndp->ndev.dev->dev_addr, ETH_ALEN);
 389         else
 390                 eth_broadcast_addr(eh->h_source);
 391
 392         /* Start the timer for the request that might not have
 393          * corresponding response. Given NCSI is an internal
 394          * connection a 1 second delay should be sufficient.
 395          */
 396         nr->enabled = true;
 397         mod_timer(&nr->timer, jiffies + 1 * HZ);
 398
 399         /* Send NCSI packet */
 400         skb_get(nr->cmd);
 401         ret = dev_queue_xmit(nr->cmd);
 402         if (ret < 0) {
 403                 ncsi_free_request(nr);
 404                 return ret;
 405         }
 406
 407         return 0;
 408 }