linux/drivers/tty/ipwireless/network.c
<<
>>
Prefs
   1/*
   2 * IPWireless 3G PCMCIA Network Driver
   3 *
   4 * Original code
   5 *   by Stephen Blackheath <stephen@blacksapphire.com>,
   6 *      Ben Martel <benm@symmetric.co.nz>
   7 *
   8 * Copyrighted as follows:
   9 *   Copyright (C) 2004 by Symmetric Systems Ltd (NZ)
  10 *
  11 * Various driver changes and rewrites, port to new kernels
  12 *   Copyright (C) 2006-2007 Jiri Kosina
  13 *
  14 * Misc code cleanups and updates
  15 *   Copyright (C) 2007 David Sterba
  16 */
  17
  18#include <linux/interrupt.h>
  19#include <linux/kernel.h>
  20#include <linux/mutex.h>
  21#include <linux/netdevice.h>
  22#include <linux/ppp_channel.h>
  23#include <linux/ppp_defs.h>
  24#include <linux/slab.h>
  25#include <linux/ppp-ioctl.h>
  26#include <linux/skbuff.h>
  27
  28#include "network.h"
  29#include "hardware.h"
  30#include "main.h"
  31#include "tty.h"
  32
  33#define MAX_ASSOCIATED_TTYS 2
  34
  35#define SC_RCV_BITS     (SC_RCV_B7_1|SC_RCV_B7_0|SC_RCV_ODDP|SC_RCV_EVNP)
  36
  37struct ipw_network {
  38        /* Hardware context, used for calls to hardware layer. */
  39        struct ipw_hardware *hardware;
  40        /* Context for kernel 'generic_ppp' functionality */
  41        struct ppp_channel *ppp_channel;
  42        /* tty context connected with IPW console */
  43        struct ipw_tty *associated_ttys[NO_OF_IPW_CHANNELS][MAX_ASSOCIATED_TTYS];
  44        /* True if ppp needs waking up once we're ready to xmit */
  45        int ppp_blocked;
  46        /* Number of packets queued up in hardware module. */
  47        int outgoing_packets_queued;
  48        /* Spinlock to avoid interrupts during shutdown */
  49        spinlock_t lock;
  50        struct mutex close_lock;
  51
  52        /* PPP ioctl data, not actually used anywere */
  53        unsigned int flags;
  54        unsigned int rbits;
  55        u32 xaccm[8];
  56        u32 raccm;
  57        int mru;
  58
  59        int shutting_down;
  60        unsigned int ras_control_lines;
  61
  62        struct work_struct work_go_online;
  63        struct work_struct work_go_offline;
  64};
  65
  66static void notify_packet_sent(void *callback_data, unsigned int packet_length)
  67{
  68        struct ipw_network *network = callback_data;
  69        unsigned long flags;
  70
  71        spin_lock_irqsave(&network->lock, flags);
  72        network->outgoing_packets_queued--;
  73        if (network->ppp_channel != NULL) {
  74                if (network->ppp_blocked) {
  75                        network->ppp_blocked = 0;
  76                        spin_unlock_irqrestore(&network->lock, flags);
  77                        ppp_output_wakeup(network->ppp_channel);
  78                        if (ipwireless_debug)
  79                                printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME
  80                                       ": ppp unblocked\n");
  81                } else
  82                        spin_unlock_irqrestore(&network->lock, flags);
  83        } else
  84                spin_unlock_irqrestore(&network->lock, flags);
  85}
  86
  87/*
  88 * Called by the ppp system when it has a packet to send to the hardware.
  89 */
  90static int ipwireless_ppp_start_xmit(struct ppp_channel *ppp_channel,
  91                                     struct sk_buff *skb)
  92{
  93        struct ipw_network *network = ppp_channel->private;
  94        unsigned long flags;
  95
  96        spin_lock_irqsave(&network->lock, flags);
  97        if (network->outgoing_packets_queued < ipwireless_out_queue) {
  98                unsigned char *buf;
  99                static unsigned char header[] = {
 100                        PPP_ALLSTATIONS, /* 0xff */
 101                        PPP_UI,          /* 0x03 */
 102                };
 103                int ret;
 104
 105                network->outgoing_packets_queued++;
 106                spin_unlock_irqrestore(&network->lock, flags);
 107
 108                /*
 109                 * If we have the requested amount of headroom in the skb we
 110                 * were handed, then we can add the header efficiently.
 111                 */
 112                if (skb_headroom(skb) >= 2) {
 113                        memcpy(skb_push(skb, 2), header, 2);
 114                        ret = ipwireless_send_packet(network->hardware,
 115                                               IPW_CHANNEL_RAS, skb->data,
 116                                               skb->len,
 117                                               notify_packet_sent,
 118                                               network);
 119                        if (ret == -1) {
 120                                skb_pull(skb, 2);
 121                                return 0;
 122                        }
 123                } else {
 124                        /* Otherwise (rarely) we do it inefficiently. */
 125                        buf = kmalloc(skb->len + 2, GFP_ATOMIC);
 126                        if (!buf)
 127                                return 0;
 128                        memcpy(buf + 2, skb->data, skb->len);
 129                        memcpy(buf, header, 2);
 130                        ret = ipwireless_send_packet(network->hardware,
 131                                               IPW_CHANNEL_RAS, buf,
 132                                               skb->len + 2,
 133                                               notify_packet_sent,
 134                                               network);
 135                        kfree(buf);
 136                        if (ret == -1)
 137                                return 0;
 138                }
 139                kfree_skb(skb);
 140                return 1;
 141        } else {
 142                /*
 143                 * Otherwise reject the packet, and flag that the ppp system
 144                 * needs to be unblocked once we are ready to send.
 145                 */
 146                network->ppp_blocked = 1;
 147                spin_unlock_irqrestore(&network->lock, flags);
 148                if (ipwireless_debug)
 149                        printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME ": ppp blocked\n");
 150                return 0;
 151        }
 152}
 153
 154/* Handle an ioctl call that has come in via ppp. (copy of ppp_async_ioctl() */
 155static int ipwireless_ppp_ioctl(struct ppp_channel *ppp_channel,
 156                                unsigned int cmd, unsigned long arg)
 157{
 158        struct ipw_network *network = ppp_channel->private;
 159        int err, val;
 160        u32 accm[8];
 161        int __user *user_arg = (int __user *) arg;
 162
 163        err = -EFAULT;
 164        switch (cmd) {
 165        case PPPIOCGFLAGS:
 166                val = network->flags | network->rbits;
 167                if (put_user(val, user_arg))
 168                        break;
 169                err = 0;
 170                break;
 171
 172        case PPPIOCSFLAGS:
 173                if (get_user(val, user_arg))
 174                        break;
 175                network->flags = val & ~SC_RCV_BITS;
 176                network->rbits = val & SC_RCV_BITS;
 177                err = 0;
 178                break;
 179
 180        case PPPIOCGASYNCMAP:
 181                if (put_user(network->xaccm[0], user_arg))
 182                        break;
 183                err = 0;
 184                break;
 185
 186        case PPPIOCSASYNCMAP:
 187                if (get_user(network->xaccm[0], user_arg))
 188                        break;
 189                err = 0;
 190                break;
 191
 192        case PPPIOCGRASYNCMAP:
 193                if (put_user(network->raccm, user_arg))
 194                        break;
 195                err = 0;
 196                break;
 197
 198        case PPPIOCSRASYNCMAP:
 199                if (get_user(network->raccm, user_arg))
 200                        break;
 201                err = 0;
 202                break;
 203
 204        case PPPIOCGXASYNCMAP:
 205                if (copy_to_user((void __user *) arg, network->xaccm,
 206                                        sizeof(network->xaccm)))
 207                        break;
 208                err = 0;
 209                break;
 210
 211        case PPPIOCSXASYNCMAP:
 212                if (copy_from_user(accm, (void __user *) arg, sizeof(accm)))
 213                        break;
 214                accm[2] &= ~0x40000000U;        /* can't escape 0x5e */
 215                accm[3] |= 0x60000000U; /* must escape 0x7d, 0x7e */
 216                memcpy(network->xaccm, accm, sizeof(network->xaccm));
 217                err = 0;
 218                break;
 219
 220        case PPPIOCGMRU:
 221                if (put_user(network->mru, user_arg))
 222                        break;
 223                err = 0;
 224                break;
 225
 226        case PPPIOCSMRU:
 227                if (get_user(val, user_arg))
 228                        break;
 229                if (val < PPP_MRU)
 230                        val = PPP_MRU;
 231                network->mru = val;
 232                err = 0;
 233                break;
 234
 235        default:
 236                err = -ENOTTY;
 237        }
 238
 239        return err;
 240}
 241
 242static const struct ppp_channel_ops ipwireless_ppp_channel_ops = {
 243        .start_xmit = ipwireless_ppp_start_xmit,
 244        .ioctl      = ipwireless_ppp_ioctl
 245};
 246
 247static void do_go_online(struct work_struct *work_go_online)
 248{
 249        struct ipw_network *network =
 250                container_of(work_go_online, struct ipw_network,
 251                                work_go_online);
 252        unsigned long flags;
 253
 254        spin_lock_irqsave(&network->lock, flags);
 255        if (!network->ppp_channel) {
 256                struct ppp_channel *channel;
 257
 258                spin_unlock_irqrestore(&network->lock, flags);
 259                channel = kzalloc(sizeof(struct ppp_channel), GFP_KERNEL);
 260                if (!channel) {
 261                        printk(KERN_ERR IPWIRELESS_PCCARD_NAME
 262                                        ": unable to allocate PPP channel\n");
 263                        return;
 264                }
 265                channel->private = network;
 266                channel->mtu = 16384;   /* Wild guess */
 267                channel->hdrlen = 2;
 268                channel->ops = &ipwireless_ppp_channel_ops;
 269
 270                network->flags = 0;
 271                network->rbits = 0;
 272                network->mru = PPP_MRU;
 273                memset(network->xaccm, 0, sizeof(network->xaccm));
 274                network->xaccm[0] = ~0U;
 275                network->xaccm[3] = 0x60000000U;
 276                network->raccm = ~0U;
 277                if (ppp_register_channel(channel) < 0) {
 278                        printk(KERN_ERR IPWIRELESS_PCCARD_NAME
 279                                        ": unable to register PPP channel\n");
 280                        kfree(channel);
 281                        return;
 282                }
 283                spin_lock_irqsave(&network->lock, flags);
 284                network->ppp_channel = channel;
 285        }
 286        spin_unlock_irqrestore(&network->lock, flags);
 287}
 288
 289static void do_go_offline(struct work_struct *work_go_offline)
 290{
 291        struct ipw_network *network =
 292                container_of(work_go_offline, struct ipw_network,
 293                                work_go_offline);
 294        unsigned long flags;
 295
 296        mutex_lock(&network->close_lock);
 297        spin_lock_irqsave(&network->lock, flags);
 298        if (network->ppp_channel != NULL) {
 299                struct ppp_channel *channel = network->ppp_channel;
 300
 301                network->ppp_channel = NULL;
 302                spin_unlock_irqrestore(&network->lock, flags);
 303                mutex_unlock(&network->close_lock);
 304                ppp_unregister_channel(channel);
 305        } else {
 306                spin_unlock_irqrestore(&network->lock, flags);
 307                mutex_unlock(&network->close_lock);
 308        }
 309}
 310
 311void ipwireless_network_notify_control_line_change(struct ipw_network *network,
 312                                                   unsigned int channel_idx,
 313                                                   unsigned int control_lines,
 314                                                   unsigned int changed_mask)
 315{
 316        int i;
 317
 318        if (channel_idx == IPW_CHANNEL_RAS)
 319                network->ras_control_lines = control_lines;
 320
 321        for (i = 0; i < MAX_ASSOCIATED_TTYS; i++) {
 322                struct ipw_tty *tty =
 323                        network->associated_ttys[channel_idx][i];
 324
 325                /*
 326                 * If it's associated with a tty (other than the RAS channel
 327                 * when we're online), then send the data to that tty.  The RAS
 328                 * channel's data is handled above - it always goes through
 329                 * ppp_generic.
 330                 */
 331                if (tty)
 332                        ipwireless_tty_notify_control_line_change(tty,
 333                                                                  channel_idx,
 334                                                                  control_lines,
 335                                                                  changed_mask);
 336        }
 337}
 338
 339/*
 340 * Some versions of firmware stuff packets with 0xff 0x03 (PPP: ALLSTATIONS, UI)
 341 * bytes, which are required on sent packet, but not always present on received
 342 * packets
 343 */
 344static struct sk_buff *ipw_packet_received_skb(unsigned char *data,
 345                                               unsigned int length)
 346{
 347        struct sk_buff *skb;
 348
 349        if (length > 2 && data[0] == PPP_ALLSTATIONS && data[1] == PPP_UI) {
 350                length -= 2;
 351                data += 2;
 352        }
 353
 354        skb = dev_alloc_skb(length + 4);
 355        if (skb == NULL)
 356                return NULL;
 357        skb_reserve(skb, 2);
 358        memcpy(skb_put(skb, length), data, length);
 359
 360        return skb;
 361}
 362
 363void ipwireless_network_packet_received(struct ipw_network *network,
 364                                        unsigned int channel_idx,
 365                                        unsigned char *data,
 366                                        unsigned int length)
 367{
 368        int i;
 369        unsigned long flags;
 370
 371        for (i = 0; i < MAX_ASSOCIATED_TTYS; i++) {
 372                struct ipw_tty *tty = network->associated_ttys[channel_idx][i];
 373
 374                if (!tty)
 375                        continue;
 376
 377                /*
 378                 * If it's associated with a tty (other than the RAS channel
 379                 * when we're online), then send the data to that tty.  The RAS
 380                 * channel's data is handled above - it always goes through
 381                 * ppp_generic.
 382                 */
 383                if (channel_idx == IPW_CHANNEL_RAS
 384                                && (network->ras_control_lines &
 385                                        IPW_CONTROL_LINE_DCD) != 0
 386                                && ipwireless_tty_is_modem(tty)) {
 387                        /*
 388                         * If data came in on the RAS channel and this tty is
 389                         * the modem tty, and we are online, then we send it to
 390                         * the PPP layer.
 391                         */
 392                        mutex_lock(&network->close_lock);
 393                        spin_lock_irqsave(&network->lock, flags);
 394                        if (network->ppp_channel != NULL) {
 395                                struct sk_buff *skb;
 396
 397                                spin_unlock_irqrestore(&network->lock,
 398                                                flags);
 399
 400                                /* Send the data to the ppp_generic module. */
 401                                skb = ipw_packet_received_skb(data, length);
 402                                if (skb)
 403                                        ppp_input(network->ppp_channel, skb);
 404                        } else
 405                                spin_unlock_irqrestore(&network->lock,
 406                                                flags);
 407                        mutex_unlock(&network->close_lock);
 408                }
 409                /* Otherwise we send it out the tty. */
 410                else
 411                        ipwireless_tty_received(tty, data, length);
 412        }
 413}
 414
 415struct ipw_network *ipwireless_network_create(struct ipw_hardware *hw)
 416{
 417        struct ipw_network *network =
 418                kzalloc(sizeof(struct ipw_network), GFP_ATOMIC);
 419
 420        if (!network)
 421                return NULL;
 422
 423        spin_lock_init(&network->lock);
 424        mutex_init(&network->close_lock);
 425
 426        network->hardware = hw;
 427
 428        INIT_WORK(&network->work_go_online, do_go_online);
 429        INIT_WORK(&network->work_go_offline, do_go_offline);
 430
 431        ipwireless_associate_network(hw, network);
 432
 433        return network;
 434}
 435
 436void ipwireless_network_free(struct ipw_network *network)
 437{
 438        network->shutting_down = 1;
 439
 440        ipwireless_ppp_close(network);
 441        flush_work(&network->work_go_online);
 442        flush_work(&network->work_go_offline);
 443
 444        ipwireless_stop_interrupts(network->hardware);
 445        ipwireless_associate_network(network->hardware, NULL);
 446
 447        kfree(network);
 448}
 449
 450void ipwireless_associate_network_tty(struct ipw_network *network,
 451                                      unsigned int channel_idx,
 452                                      struct ipw_tty *tty)
 453{
 454        int i;
 455
 456        for (i = 0; i < MAX_ASSOCIATED_TTYS; i++)
 457                if (network->associated_ttys[channel_idx][i] == NULL) {
 458                        network->associated_ttys[channel_idx][i] = tty;
 459                        break;
 460                }
 461}
 462
 463void ipwireless_disassociate_network_ttys(struct ipw_network *network,
 464                                          unsigned int channel_idx)
 465{
 466        int i;
 467
 468        for (i = 0; i < MAX_ASSOCIATED_TTYS; i++)
 469                network->associated_ttys[channel_idx][i] = NULL;
 470}
 471
 472void ipwireless_ppp_open(struct ipw_network *network)
 473{
 474        if (ipwireless_debug)
 475                printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME ": online\n");
 476        schedule_work(&network->work_go_online);
 477}
 478
 479void ipwireless_ppp_close(struct ipw_network *network)
 480{
 481        /* Disconnect from the wireless network. */
 482        if (ipwireless_debug)
 483                printk(KERN_DEBUG IPWIRELESS_PCCARD_NAME ": offline\n");
 484        schedule_work(&network->work_go_offline);
 485}
 486
 487int ipwireless_ppp_channel_index(struct ipw_network *network)
 488{
 489        int ret = -1;
 490        unsigned long flags;
 491
 492        spin_lock_irqsave(&network->lock, flags);
 493        if (network->ppp_channel != NULL)
 494                ret = ppp_channel_index(network->ppp_channel);
 495        spin_unlock_irqrestore(&network->lock, flags);
 496
 497        return ret;
 498}
 499
 500int ipwireless_ppp_unit_number(struct ipw_network *network)
 501{
 502        int ret = -1;
 503        unsigned long flags;
 504
 505        spin_lock_irqsave(&network->lock, flags);
 506        if (network->ppp_channel != NULL)
 507                ret = ppp_unit_number(network->ppp_channel);
 508        spin_unlock_irqrestore(&network->lock, flags);
 509
 510        return ret;
 511}
 512
 513int ipwireless_ppp_mru(const struct ipw_network *network)
 514{
 515        return network->mru;
 516}
 517