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