drivers/staging/ozwpan/ozproto.c

   1 /* -----------------------------------------------------------------------------
   2  * Copyright (c) 2011 Ozmo Inc
   3  * Released under the GNU General Public License Version 2 (GPLv2).
   4  * -----------------------------------------------------------------------------
   5  */
   6
   7 #include <linux/module.h>
   8 #include <linux/timer.h>
   9 #include <linux/sched.h>
  10 #include <linux/netdevice.h>
  11 #include <linux/etherdevice.h>
  12 #include <linux/errno.h>
  13 #include <linux/ieee80211.h>
  14 #include "ozdbg.h"
  15 #include "ozprotocol.h"
  16 #include "ozeltbuf.h"
  17 #include "ozpd.h"
  18 #include "ozproto.h"
  19 #include "ozusbsvc.h"
  20
  21 #include "ozappif.h"
  22 #include <asm/unaligned.h>
  23 #include <linux/uaccess.h>
  24 #include <net/psnap.h>
  25
  26 #define OZ_CF_CONN_SUCCESS      1
  27 #define OZ_CF_CONN_FAILURE      2
  28
  29 #define OZ_DO_STOP              1
  30 #define OZ_DO_SLEEP             2
  31
  32 struct oz_binding {
  33         struct packet_type ptype;
  34         char name[OZ_MAX_BINDING_LEN];
  35         struct list_head link;
  36 };
  37
  38 /*
  39  * External variable
  40  */
  41
  42 DEFINE_SPINLOCK(g_polling_lock);
  43 /*
  44  * Static external variables.
  45  */
  46 static LIST_HEAD(g_pd_list);
  47 static LIST_HEAD(g_binding);
  48 static DEFINE_SPINLOCK(g_binding_lock);
  49 static struct sk_buff_head g_rx_queue;
  50 static u8 g_session_id;
  51 static u16 g_apps = 0x1;
  52 static int g_processing_rx;
  53
  54 /*
  55  * Context: softirq-serialized
  56  */
  57 static u8 oz_get_new_session_id(u8 exclude)
  58 {
  59         if (++g_session_id == 0)
  60                 g_session_id = 1;
  61         if (g_session_id == exclude) {
  62                 if (++g_session_id == 0)
  63                         g_session_id = 1;
  64         }
  65         return g_session_id;
  66 }
  67
  68 /*
  69  * Context: softirq-serialized
  70  */
  71 static void oz_send_conn_rsp(struct oz_pd *pd, u8 status)
  72 {
  73         struct sk_buff *skb;
  74         struct net_device *dev = pd->net_dev;
  75         struct oz_hdr *oz_hdr;
  76         struct oz_elt *elt;
  77         struct oz_elt_connect_rsp *body;
  78
  79         int sz = sizeof(struct oz_hdr) + sizeof(struct oz_elt) +
  80                         sizeof(struct oz_elt_connect_rsp);
  81         skb = alloc_skb(sz + OZ_ALLOCATED_SPACE(dev), GFP_ATOMIC);
  82         if (skb == NULL)
  83                 return;
  84         skb_reserve(skb, LL_RESERVED_SPACE(dev));
  85         skb_reset_network_header(skb);
  86         oz_hdr = (struct oz_hdr *)skb_put(skb, sz);
  87         elt = (struct oz_elt *)(oz_hdr+1);
  88         body = (struct oz_elt_connect_rsp *)(elt+1);
  89         skb->dev = dev;
  90         skb->protocol = htons(OZ_ETHERTYPE);
  91         /* Fill in device header */
  92         if (dev_hard_header(skb, dev, OZ_ETHERTYPE, pd->mac_addr,
  93                         dev->dev_addr, skb->len) < 0) {
  94                 kfree_skb(skb);
  95                 return;
  96         }
  97         oz_hdr->control = (OZ_PROTOCOL_VERSION<<OZ_VERSION_SHIFT);
  98         oz_hdr->last_pkt_num = 0;
  99         put_unaligned(0, &oz_hdr->pkt_num);
 100         elt->type = OZ_ELT_CONNECT_RSP;
 101         elt->length = sizeof(struct oz_elt_connect_rsp);
 102         memset(body, 0, sizeof(struct oz_elt_connect_rsp));
 103         body->status = status;
 104         if (status == 0) {
 105                 body->mode = pd->mode;
 106                 body->session_id = pd->session_id;
 107                 put_unaligned(cpu_to_le16(pd->total_apps), &body->apps);
 108         }
 109         oz_dbg(ON, "TX: OZ_ELT_CONNECT_RSP %d", status);
 110         dev_queue_xmit(skb);
 111         return;
 112 }
 113
 114 /*
 115  * Context: softirq-serialized
 116  */
 117 static void pd_set_keepalive(struct oz_pd *pd, u8 kalive)
 118 {
 119         unsigned long keep_alive = kalive & OZ_KALIVE_VALUE_MASK;
 120
 121         switch (kalive & OZ_KALIVE_TYPE_MASK) {
 122         case OZ_KALIVE_SPECIAL:
 123                 pd->keep_alive = keep_alive * 1000*60*60*24*20;
 124                 break;
 125         case OZ_KALIVE_SECS:
 126                 pd->keep_alive = keep_alive*1000;
 127                 break;
 128         case OZ_KALIVE_MINS:
 129                 pd->keep_alive = keep_alive*1000*60;
 130                 break;
 131         case OZ_KALIVE_HOURS:
 132                 pd->keep_alive = keep_alive*1000*60*60;
 133                 break;
 134         default:
 135                 pd->keep_alive = 0;
 136         }
 137         oz_dbg(ON, "Keepalive = %lu mSec\n", pd->keep_alive);
 138 }
 139
 140 /*
 141  * Context: softirq-serialized
 142  */
 143 static void pd_set_presleep(struct oz_pd *pd, u8 presleep, u8 start_timer)
 144 {
 145         if (presleep)
 146                 pd->presleep = presleep*100;
 147         else
 148                 pd->presleep = OZ_PRESLEEP_TOUT;
 149         if (start_timer) {
 150                 spin_unlock(&g_polling_lock);
 151                 oz_timer_add(pd, OZ_TIMER_TOUT, pd->presleep);
 152                 spin_lock(&g_polling_lock);
 153         }
 154         oz_dbg(ON, "Presleep time = %lu mSec\n", pd->presleep);
 155 }
 156
 157 /*
 158  * Context: softirq-serialized
 159  */
 160 static struct oz_pd *oz_connect_req(struct oz_pd *cur_pd, struct oz_elt *elt,
 161                         const u8 *pd_addr, struct net_device *net_dev)
 162 {
 163         struct oz_pd *pd;
 164         struct oz_elt_connect_req *body =
 165                         (struct oz_elt_connect_req *)(elt+1);
 166         u8 rsp_status = OZ_STATUS_SUCCESS;
 167         u8 stop_needed = 0;
 168         u16 new_apps = g_apps;
 169         struct net_device *old_net_dev = NULL;
 170         struct oz_pd *free_pd = NULL;
 171
 172         if (cur_pd) {
 173                 pd = cur_pd;
 174                 spin_lock_bh(&g_polling_lock);
 175         } else {
 176                 struct oz_pd *pd2 = NULL;
 177                 struct list_head *e;
 178                 pd = oz_pd_alloc(pd_addr);
 179                 if (pd == NULL)
 180                         return NULL;
 181                 getnstimeofday(&pd->last_rx_timestamp);
 182                 spin_lock_bh(&g_polling_lock);
 183                 list_for_each(e, &g_pd_list) {
 184                         pd2 = container_of(e, struct oz_pd, link);
 185                         if (ether_addr_equal(pd2->mac_addr, pd_addr)) {
 186                                 free_pd = pd;
 187                                 pd = pd2;
 188                                 break;
 189                         }
 190                 }
 191                 if (pd != pd2)
 192                         list_add_tail(&pd->link, &g_pd_list);
 193         }
 194         if (pd == NULL) {
 195                 spin_unlock_bh(&g_polling_lock);
 196                 return NULL;
 197         }
 198         if (pd->net_dev != net_dev) {
 199                 old_net_dev = pd->net_dev;
 200                 dev_hold(net_dev);
 201                 pd->net_dev = net_dev;
 202         }
 203         oz_dbg(ON, "Host vendor: %d\n", body->host_vendor);
 204         pd->max_tx_size = OZ_MAX_TX_SIZE;
 205         pd->mode = body->mode;
 206         pd->pd_info = body->pd_info;
 207         if (pd->mode & OZ_F_ISOC_NO_ELTS) {
 208                 pd->ms_per_isoc = body->ms_per_isoc;
 209                 if (!pd->ms_per_isoc)
 210                         pd->ms_per_isoc = 4;
 211
 212                 switch (body->ms_isoc_latency & OZ_LATENCY_MASK) {
 213                 case OZ_ONE_MS_LATENCY:
 214                         pd->isoc_latency = (body->ms_isoc_latency &
 215                                         ~OZ_LATENCY_MASK) / pd->ms_per_isoc;
 216                         break;
 217                 case OZ_TEN_MS_LATENCY:
 218                         pd->isoc_latency = ((body->ms_isoc_latency &
 219                                 ~OZ_LATENCY_MASK) * 10) / pd->ms_per_isoc;
 220                         break;
 221                 default:
 222                         pd->isoc_latency = OZ_MAX_TX_QUEUE_ISOC;
 223                 }
 224         }
 225         if (body->max_len_div16)
 226                 pd->max_tx_size = ((u16)body->max_len_div16)<<4;
 227         oz_dbg(ON, "Max frame:%u Ms per isoc:%u\n",
 228                pd->max_tx_size, pd->ms_per_isoc);
 229         pd->max_stream_buffering = 3*1024;
 230         pd->pulse_period = OZ_QUANTUM;
 231         pd_set_presleep(pd, body->presleep, 0);
 232         pd_set_keepalive(pd, body->keep_alive);
 233
 234         new_apps &= le16_to_cpu(get_unaligned(&body->apps));
 235         if ((new_apps & 0x1) && (body->session_id)) {
 236                 if (pd->session_id) {
 237                         if (pd->session_id != body->session_id) {
 238                                 rsp_status = OZ_STATUS_SESSION_MISMATCH;
 239                                 goto done;
 240                         }
 241                 } else {
 242                         new_apps &= ~0x1;  /* Resume not permitted */
 243                         pd->session_id =
 244                                 oz_get_new_session_id(body->session_id);
 245                 }
 246         } else {
 247                 if (pd->session_id && !body->session_id) {
 248                         rsp_status = OZ_STATUS_SESSION_TEARDOWN;
 249                         stop_needed = 1;
 250                 } else {
 251                         new_apps &= ~0x1;  /* Resume not permitted */
 252                         pd->session_id =
 253                                 oz_get_new_session_id(body->session_id);
 254                 }
 255         }
 256 done:
 257         if (rsp_status == OZ_STATUS_SUCCESS) {
 258                 u16 start_apps = new_apps & ~pd->total_apps & ~0x1;
 259                 u16 stop_apps = pd->total_apps & ~new_apps & ~0x1;
 260                 u16 resume_apps = new_apps & pd->paused_apps  & ~0x1;
 261                 spin_unlock_bh(&g_polling_lock);
 262                 oz_pd_set_state(pd, OZ_PD_S_CONNECTED);
 263                 oz_dbg(ON, "new_apps=0x%x total_apps=0x%x paused_apps=0x%x\n",
 264                        new_apps, pd->total_apps, pd->paused_apps);
 265                 if (start_apps) {
 266                         if (oz_services_start(pd, start_apps, 0))
 267                                 rsp_status = OZ_STATUS_TOO_MANY_PDS;
 268                 }
 269                 if (resume_apps)
 270                         if (oz_services_start(pd, resume_apps, 1))
 271                                 rsp_status = OZ_STATUS_TOO_MANY_PDS;
 272                 if (stop_apps)
 273                         oz_services_stop(pd, stop_apps, 0);
 274                 oz_pd_request_heartbeat(pd);
 275         } else {
 276                 spin_unlock_bh(&g_polling_lock);
 277         }
 278         oz_send_conn_rsp(pd, rsp_status);
 279         if (rsp_status != OZ_STATUS_SUCCESS) {
 280                 if (stop_needed)
 281                         oz_pd_stop(pd);
 282                 oz_pd_put(pd);
 283                 pd = NULL;
 284         }
 285         if (old_net_dev)
 286                 dev_put(old_net_dev);
 287         if (free_pd)
 288                 oz_pd_destroy(free_pd);
 289         return pd;
 290 }
 291
 292 /*
 293  * Context: softirq-serialized
 294  */
 295 static void oz_add_farewell(struct oz_pd *pd, u8 ep_num, u8 index,
 296                         const u8 *report, u8 len)
 297 {
 298         struct oz_farewell *f;
 299         struct oz_farewell *f2;
 300         int found = 0;
 301
 302         f = kmalloc(sizeof(struct oz_farewell) + len, GFP_ATOMIC);
 303         if (!f)
 304                 return;
 305         f->ep_num = ep_num;
 306         f->index = index;
 307         f->len = len;
 308         memcpy(f->report, report, len);
 309         oz_dbg(ON, "RX: Adding farewell report\n");
 310         spin_lock(&g_polling_lock);
 311         list_for_each_entry(f2, &pd->farewell_list, link) {
 312                 if ((f2->ep_num == ep_num) && (f2->index == index)) {
 313                         found = 1;
 314                         list_del(&f2->link);
 315                         break;
 316                 }
 317         }
 318         list_add_tail(&f->link, &pd->farewell_list);
 319         spin_unlock(&g_polling_lock);
 320         if (found)
 321                 kfree(f2);
 322 }
 323
 324 /*
 325  * Context: softirq-serialized
 326  */
 327 static void oz_rx_frame(struct sk_buff *skb)
 328 {
 329         u8 *mac_hdr;
 330         u8 *src_addr;
 331         struct oz_elt *elt;
 332         int length;
 333         struct oz_pd *pd = NULL;
 334         struct oz_hdr *oz_hdr = (struct oz_hdr *)skb_network_header(skb);
 335         struct timespec current_time;
 336         int dup = 0;
 337         u32 pkt_num;
 338
 339         oz_dbg(RX_FRAMES, "RX frame PN=0x%x LPN=0x%x control=0x%x\n",
 340                oz_hdr->pkt_num, oz_hdr->last_pkt_num, oz_hdr->control);
 341         mac_hdr = skb_mac_header(skb);
 342         src_addr = &mac_hdr[ETH_ALEN];
 343         length = skb->len;
 344
 345         /* Check the version field */
 346         if (oz_get_prot_ver(oz_hdr->control) != OZ_PROTOCOL_VERSION) {
 347                 oz_dbg(ON, "Incorrect protocol version: %d\n",
 348                        oz_get_prot_ver(oz_hdr->control));
 349                 goto done;
 350         }
 351
 352         pkt_num = le32_to_cpu(get_unaligned(&oz_hdr->pkt_num));
 353
 354         pd = oz_pd_find(src_addr);
 355         if (pd) {
 356                 if (!(pd->state & OZ_PD_S_CONNECTED))
 357                         oz_pd_set_state(pd, OZ_PD_S_CONNECTED);
 358                 getnstimeofday(&current_time);
 359                 if ((current_time.tv_sec != pd->last_rx_timestamp.tv_sec) ||
 360                         (pd->presleep < MSEC_PER_SEC))  {
 361                         oz_timer_add(pd, OZ_TIMER_TOUT, pd->presleep);
 362                         pd->last_rx_timestamp = current_time;
 363                 }
 364                 if (pkt_num != pd->last_rx_pkt_num) {
 365                         pd->last_rx_pkt_num = pkt_num;
 366                 } else {
 367                         dup = 1;
 368                         oz_dbg(ON, "Duplicate frame\n");
 369                 }
 370         }
 371
 372         if (pd && !dup && ((pd->mode & OZ_MODE_MASK) == OZ_MODE_TRIGGERED)) {
 373                 oz_dbg(RX_FRAMES, "Received TRIGGER Frame\n");
 374                 pd->last_sent_frame = &pd->tx_queue;
 375                 if (oz_hdr->control & OZ_F_ACK) {
 376                         /* Retire completed frames */
 377                         oz_retire_tx_frames(pd, oz_hdr->last_pkt_num);
 378                 }
 379                 if ((oz_hdr->control & OZ_F_ACK_REQUESTED) &&
 380                                 (pd->state == OZ_PD_S_CONNECTED)) {
 381                         int backlog = pd->nb_queued_frames;
 382                         pd->trigger_pkt_num = pkt_num;
 383                         /* Send queued frames */
 384                         oz_send_queued_frames(pd, backlog);
 385                 }
 386         }
 387
 388         length -= sizeof(struct oz_hdr);
 389         elt = (struct oz_elt *)((u8 *)oz_hdr + sizeof(struct oz_hdr));
 390
 391         while (length >= sizeof(struct oz_elt)) {
 392                 length -= sizeof(struct oz_elt) + elt->length;
 393                 if (length < 0)
 394                         break;
 395                 switch (elt->type) {
 396                 case OZ_ELT_CONNECT_REQ:
 397                         oz_dbg(ON, "RX: OZ_ELT_CONNECT_REQ\n");
 398                         pd = oz_connect_req(pd, elt, src_addr, skb->dev);
 399                         break;
 400                 case OZ_ELT_DISCONNECT:
 401                         oz_dbg(ON, "RX: OZ_ELT_DISCONNECT\n");
 402                         if (pd)
 403                                 oz_pd_sleep(pd);
 404                         break;
 405                 case OZ_ELT_UPDATE_PARAM_REQ: {
 406                                 struct oz_elt_update_param *body =
 407                                         (struct oz_elt_update_param *)(elt + 1);
 408                                 oz_dbg(ON, "RX: OZ_ELT_UPDATE_PARAM_REQ\n");
 409                                 if (pd && (pd->state & OZ_PD_S_CONNECTED)) {
 410                                         spin_lock(&g_polling_lock);
 411                                         pd_set_keepalive(pd, body->keepalive);
 412                                         pd_set_presleep(pd, body->presleep, 1);
 413                                         spin_unlock(&g_polling_lock);
 414                                 }
 415                         }
 416                         break;
 417                 case OZ_ELT_FAREWELL_REQ: {
 418                                 struct oz_elt_farewell *body =
 419                                         (struct oz_elt_farewell *)(elt + 1);
 420                                 oz_dbg(ON, "RX: OZ_ELT_FAREWELL_REQ\n");
 421                                 oz_add_farewell(pd, body->ep_num,
 422                                         body->index, body->report,
 423                                         elt->length + 1 - sizeof(*body));
 424                         }
 425                         break;
 426                 case OZ_ELT_APP_DATA:
 427                         if (pd && (pd->state & OZ_PD_S_CONNECTED)) {
 428                                 struct oz_app_hdr *app_hdr =
 429                                         (struct oz_app_hdr *)(elt+1);
 430                                 if (dup)
 431                                         break;
 432                                 oz_handle_app_elt(pd, app_hdr->app_id, elt);
 433                         }
 434                         break;
 435                 default:
 436                         oz_dbg(ON, "RX: Unknown elt %02x\n", elt->type);
 437                 }
 438                 elt = oz_next_elt(elt);
 439         }
 440 done:
 441         if (pd)
 442                 oz_pd_put(pd);
 443         consume_skb(skb);
 444 }
 445
 446 /*
 447  * Context: process
 448  */
 449 void oz_protocol_term(void)
 450 {
 451         struct oz_binding *b, *t;
 452
 453         /* Walk the list of bindings and remove each one.
 454          */
 455         spin_lock_bh(&g_binding_lock);
 456         list_for_each_entry_safe(b, t, &g_binding, link) {
 457                 list_del(&b->link);
 458                 spin_unlock_bh(&g_binding_lock);
 459                 dev_remove_pack(&b->ptype);
 460                 if (b->ptype.dev)
 461                         dev_put(b->ptype.dev);
 462                 kfree(b);
 463                 spin_lock_bh(&g_binding_lock);
 464         }
 465         spin_unlock_bh(&g_binding_lock);
 466         /* Walk the list of PDs and stop each one. This causes the PD to be
 467          * removed from the list so we can just pull each one from the head
 468          * of the list.
 469          */
 470         spin_lock_bh(&g_polling_lock);
 471         while (!list_empty(&g_pd_list)) {
 472                 struct oz_pd *pd =
 473                         list_first_entry(&g_pd_list, struct oz_pd, link);
 474                 oz_pd_get(pd);
 475                 spin_unlock_bh(&g_polling_lock);
 476                 oz_pd_stop(pd);
 477                 oz_pd_put(pd);
 478                 spin_lock_bh(&g_polling_lock);
 479         }
 480         spin_unlock_bh(&g_polling_lock);
 481         oz_dbg(ON, "Protocol stopped\n");
 482 }
 483
 484 /*
 485  * Context: softirq
 486  */
 487 void oz_pd_heartbeat_handler(unsigned long data)
 488 {
 489         struct oz_pd *pd = (struct oz_pd *)data;
 490         u16 apps = 0;
 491
 492         spin_lock_bh(&g_polling_lock);
 493         if (pd->state & OZ_PD_S_CONNECTED)
 494                 apps = pd->total_apps;
 495         spin_unlock_bh(&g_polling_lock);
 496         if (apps)
 497                 oz_pd_heartbeat(pd, apps);
 498         oz_pd_put(pd);
 499 }
 500
 501 /*
 502  * Context: softirq
 503  */
 504 void oz_pd_timeout_handler(unsigned long data)
 505 {
 506         int type;
 507         struct oz_pd *pd = (struct oz_pd *)data;
 508
 509         spin_lock_bh(&g_polling_lock);
 510         type = pd->timeout_type;
 511         spin_unlock_bh(&g_polling_lock);
 512         switch (type) {
 513         case OZ_TIMER_TOUT:
 514                 oz_pd_sleep(pd);
 515                 break;
 516         case OZ_TIMER_STOP:
 517                 oz_pd_stop(pd);
 518                 break;
 519         }
 520         oz_pd_put(pd);
 521 }
 522
 523 /*
 524  * Context: Interrupt
 525  */
 526 enum hrtimer_restart oz_pd_heartbeat_event(struct hrtimer *timer)
 527 {
 528         struct oz_pd *pd;
 529
 530         pd = container_of(timer, struct oz_pd, heartbeat);
 531         hrtimer_forward_now(timer, ktime_set(pd->pulse_period /
 532         MSEC_PER_SEC, (pd->pulse_period % MSEC_PER_SEC) * NSEC_PER_MSEC));
 533         oz_pd_get(pd);
 534         tasklet_schedule(&pd->heartbeat_tasklet);
 535         return HRTIMER_RESTART;
 536 }
 537
 538 /*
 539  * Context: Interrupt
 540  */
 541 enum hrtimer_restart oz_pd_timeout_event(struct hrtimer *timer)
 542 {
 543         struct oz_pd *pd;
 544
 545         pd = container_of(timer, struct oz_pd, timeout);
 546         oz_pd_get(pd);
 547         tasklet_schedule(&pd->timeout_tasklet);
 548         return HRTIMER_NORESTART;
 549 }
 550
 551 /*
 552  * Context: softirq or process
 553  */
 554 void oz_timer_add(struct oz_pd *pd, int type, unsigned long due_time)
 555 {
 556         spin_lock_bh(&g_polling_lock);
 557         switch (type) {
 558         case OZ_TIMER_TOUT:
 559         case OZ_TIMER_STOP:
 560                 if (hrtimer_active(&pd->timeout)) {
 561                         hrtimer_set_expires(&pd->timeout, ktime_set(due_time /
 562                         MSEC_PER_SEC, (due_time % MSEC_PER_SEC) *
 563                                                         NSEC_PER_MSEC));
 564                         hrtimer_start_expires(&pd->timeout, HRTIMER_MODE_REL);
 565                 } else {
 566                         hrtimer_start(&pd->timeout, ktime_set(due_time /
 567                         MSEC_PER_SEC, (due_time % MSEC_PER_SEC) *
 568                                         NSEC_PER_MSEC), HRTIMER_MODE_REL);
 569                 }
 570                 pd->timeout_type = type;
 571                 break;
 572         case OZ_TIMER_HEARTBEAT:
 573                 if (!hrtimer_active(&pd->heartbeat))
 574                         hrtimer_start(&pd->heartbeat, ktime_set(due_time /
 575                         MSEC_PER_SEC, (due_time % MSEC_PER_SEC) *
 576                                         NSEC_PER_MSEC), HRTIMER_MODE_REL);
 577                 break;
 578         }
 579         spin_unlock_bh(&g_polling_lock);
 580 }
 581
 582 /*
 583  * Context: softirq or process
 584  */
 585 void oz_pd_request_heartbeat(struct oz_pd *pd)
 586 {
 587         oz_timer_add(pd, OZ_TIMER_HEARTBEAT, pd->pulse_period > 0 ?
 588                                         pd->pulse_period : OZ_QUANTUM);
 589 }
 590
 591 /*
 592  * Context: softirq or process
 593  */
 594 struct oz_pd *oz_pd_find(const u8 *mac_addr)
 595 {
 596         struct oz_pd *pd;
 597         struct list_head *e;
 598
 599         spin_lock_bh(&g_polling_lock);
 600         list_for_each(e, &g_pd_list) {
 601                 pd = container_of(e, struct oz_pd, link);
 602                 if (ether_addr_equal(pd->mac_addr, mac_addr)) {
 603                         atomic_inc(&pd->ref_count);
 604                         spin_unlock_bh(&g_polling_lock);
 605                         return pd;
 606                 }
 607         }
 608         spin_unlock_bh(&g_polling_lock);
 609         return NULL;
 610 }
 611
 612 /*
 613  * Context: process
 614  */
 615 void oz_app_enable(int app_id, int enable)
 616 {
 617         if (app_id <= OZ_APPID_MAX) {
 618                 spin_lock_bh(&g_polling_lock);
 619                 if (enable)
 620                         g_apps |= (1<<app_id);
 621                 else
 622                         g_apps &= ~(1<<app_id);
 623                 spin_unlock_bh(&g_polling_lock);
 624         }
 625 }
 626
 627 /*
 628  * Context: softirq
 629  */
 630 static int oz_pkt_recv(struct sk_buff *skb, struct net_device *dev,
 631                 struct packet_type *pt, struct net_device *orig_dev)
 632 {
 633         skb = skb_share_check(skb, GFP_ATOMIC);
 634         if (skb == NULL)
 635                 return 0;
 636         spin_lock_bh(&g_rx_queue.lock);
 637         if (g_processing_rx) {
 638                 /* We already hold the lock so use __ variant.
 639                  */
 640                 __skb_queue_head(&g_rx_queue, skb);
 641                 spin_unlock_bh(&g_rx_queue.lock);
 642         } else {
 643                 g_processing_rx = 1;
 644                 do {
 645
 646                         spin_unlock_bh(&g_rx_queue.lock);
 647                         oz_rx_frame(skb);
 648                         spin_lock_bh(&g_rx_queue.lock);
 649                         if (skb_queue_empty(&g_rx_queue)) {
 650                                 g_processing_rx = 0;
 651                                 spin_unlock_bh(&g_rx_queue.lock);
 652                                 break;
 653                         }
 654                         /* We already hold the lock so use __ variant.
 655                          */
 656                         skb = __skb_dequeue(&g_rx_queue);
 657                 } while (1);
 658         }
 659         return 0;
 660 }
 661
 662 /*
 663  * Context: process
 664  */
 665 void oz_binding_add(const char *net_dev)
 666 {
 667         struct oz_binding *binding;
 668
 669         binding = kzalloc(sizeof(struct oz_binding), GFP_KERNEL);
 670         if (!binding)
 671                 return;
 672
 673         binding->ptype.type = htons(OZ_ETHERTYPE);
 674         binding->ptype.func = oz_pkt_recv;
 675         if (net_dev && *net_dev) {
 676                 memcpy(binding->name, net_dev, OZ_MAX_BINDING_LEN);
 677                 oz_dbg(ON, "Adding binding: %s\n", net_dev);
 678                 binding->ptype.dev = dev_get_by_name(&init_net, net_dev);
 679                 if (binding->ptype.dev == NULL) {
 680                         oz_dbg(ON, "Netdev %s not found\n", net_dev);
 681                         kfree(binding);
 682                         return;
 683                 }
 684         }
 685         dev_add_pack(&binding->ptype);
 686         spin_lock_bh(&g_binding_lock);
 687         list_add_tail(&binding->link, &g_binding);
 688         spin_unlock_bh(&g_binding_lock);
 689 }
 690
 691 /*
 692  * Context: process
 693  */
 694 static void pd_stop_all_for_device(struct net_device *net_dev)
 695 {
 696         struct list_head h;
 697         struct oz_pd *pd;
 698         struct oz_pd *n;
 699
 700         INIT_LIST_HEAD(&h);
 701         spin_lock_bh(&g_polling_lock);
 702         list_for_each_entry_safe(pd, n, &g_pd_list, link) {
 703                 if (pd->net_dev == net_dev) {
 704                         list_move(&pd->link, &h);
 705                         oz_pd_get(pd);
 706                 }
 707         }
 708         spin_unlock_bh(&g_polling_lock);
 709         while (!list_empty(&h)) {
 710                 pd = list_first_entry(&h, struct oz_pd, link);
 711                 oz_pd_stop(pd);
 712                 oz_pd_put(pd);
 713         }
 714 }
 715
 716 /*
 717  * Context: process
 718  */
 719 void oz_binding_remove(const char *net_dev)
 720 {
 721         struct oz_binding *binding;
 722         int found = 0;
 723
 724         oz_dbg(ON, "Removing binding: %s\n", net_dev);
 725         spin_lock_bh(&g_binding_lock);
 726         list_for_each_entry(binding, &g_binding, link) {
 727                 if (strncmp(binding->name, net_dev, OZ_MAX_BINDING_LEN) == 0) {
 728                         oz_dbg(ON, "Binding '%s' found\n", net_dev);
 729                         found = 1;
 730                         break;
 731                 }
 732         }
 733         spin_unlock_bh(&g_binding_lock);
 734         if (found) {
 735                 dev_remove_pack(&binding->ptype);
 736                 if (binding->ptype.dev) {
 737                         dev_put(binding->ptype.dev);
 738                         pd_stop_all_for_device(binding->ptype.dev);
 739                 }
 740                 list_del(&binding->link);
 741                 kfree(binding);
 742         }
 743 }
 744
 745 /*
 746  * Context: process
 747  */
 748 static char *oz_get_next_device_name(char *s, char *dname, int max_size)
 749 {
 750         while (*s == ',')
 751                 s++;
 752         while (*s && (*s != ',') && max_size > 1) {
 753                 *dname++ = *s++;
 754                 max_size--;
 755         }
 756         *dname = 0;
 757         return s;
 758 }
 759
 760 /*
 761  * Context: process
 762  */
 763 int oz_protocol_init(char *devs)
 764 {
 765         skb_queue_head_init(&g_rx_queue);
 766         if (devs[0] == '*') {
 767                 oz_binding_add(NULL);
 768         } else {
 769                 char d[32];
 770                 while (*devs) {
 771                         devs = oz_get_next_device_name(devs, d, sizeof(d));
 772                         if (d[0])
 773                                 oz_binding_add(d);
 774                 }
 775         }
 776         return 0;
 777 }
 778
 779 /*
 780  * Context: process
 781  */
 782 int oz_get_pd_list(struct oz_mac_addr *addr, int max_count)
 783 {
 784         struct oz_pd *pd;
 785         struct list_head *e;
 786         int count = 0;
 787
 788         spin_lock_bh(&g_polling_lock);
 789         list_for_each(e, &g_pd_list) {
 790                 if (count >= max_count)
 791                         break;
 792                 pd = container_of(e, struct oz_pd, link);
 793                 ether_addr_copy((u8 *)&addr[count++], pd->mac_addr);
 794         }
 795         spin_unlock_bh(&g_polling_lock);
 796         return count;
 797 }
 798