net/atm/common.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /* net/atm/common.c - ATM sockets (common part for PVC and SVC) */
   3
   4 /* Written 1995-2000 by Werner Almesberger, EPFL LRC/ICA */
   5
   6 #define pr_fmt(fmt) KBUILD_MODNAME ":%s: " fmt, __func__
   7
   8 #include <linux/module.h>
   9 #include <linux/kmod.h>
  10 #include <linux/net.h>          /* struct socket, struct proto_ops */
  11 #include <linux/atm.h>          /* ATM stuff */
  12 #include <linux/atmdev.h>
  13 #include <linux/socket.h>       /* SOL_SOCKET */
  14 #include <linux/errno.h>        /* error codes */
  15 #include <linux/capability.h>
  16 #include <linux/mm.h>
  17 #include <linux/sched/signal.h>
  18 #include <linux/time64.h>       /* 64-bit time for seconds */
  19 #include <linux/skbuff.h>
  20 #include <linux/bitops.h>
  21 #include <linux/init.h>
  22 #include <linux/slab.h>
  23 #include <net/sock.h>           /* struct sock */
  24 #include <linux/uaccess.h>
  25 #include <linux/poll.h>
  26
  27 #include <linux/atomic.h>
  28
  29 #include "resources.h"          /* atm_find_dev */
  30 #include "common.h"             /* prototypes */
  31 #include "protocols.h"          /* atm_init_<transport> */
  32 #include "addr.h"               /* address registry */
  33 #include "signaling.h"          /* for WAITING and sigd_attach */
  34
  35 struct hlist_head vcc_hash[VCC_HTABLE_SIZE];
  36 EXPORT_SYMBOL(vcc_hash);
  37
  38 DEFINE_RWLOCK(vcc_sklist_lock);
  39 EXPORT_SYMBOL(vcc_sklist_lock);
  40
  41 static ATOMIC_NOTIFIER_HEAD(atm_dev_notify_chain);
  42
  43 static void __vcc_insert_socket(struct sock *sk)
  44 {
  45         struct atm_vcc *vcc = atm_sk(sk);
  46         struct hlist_head *head = &vcc_hash[vcc->vci & (VCC_HTABLE_SIZE - 1)];
  47         sk->sk_hash = vcc->vci & (VCC_HTABLE_SIZE - 1);
  48         sk_add_node(sk, head);
  49 }
  50
  51 void vcc_insert_socket(struct sock *sk)
  52 {
  53         write_lock_irq(&vcc_sklist_lock);
  54         __vcc_insert_socket(sk);
  55         write_unlock_irq(&vcc_sklist_lock);
  56 }
  57 EXPORT_SYMBOL(vcc_insert_socket);
  58
  59 static void vcc_remove_socket(struct sock *sk)
  60 {
  61         write_lock_irq(&vcc_sklist_lock);
  62         sk_del_node_init(sk);
  63         write_unlock_irq(&vcc_sklist_lock);
  64 }
  65
  66 static bool vcc_tx_ready(struct atm_vcc *vcc, unsigned int size)
  67 {
  68         struct sock *sk = sk_atm(vcc);
  69
  70         if (sk_wmem_alloc_get(sk) && !atm_may_send(vcc, size)) {
  71                 pr_debug("Sorry: wmem_alloc = %d, size = %d, sndbuf = %d\n",
  72                          sk_wmem_alloc_get(sk), size, sk->sk_sndbuf);
  73                 return false;
  74         }
  75         return true;
  76 }
  77
  78 static void vcc_sock_destruct(struct sock *sk)
  79 {
  80         if (atomic_read(&sk->sk_rmem_alloc))
  81                 printk(KERN_DEBUG "%s: rmem leakage (%d bytes) detected.\n",
  82                        __func__, atomic_read(&sk->sk_rmem_alloc));
  83
  84         if (refcount_read(&sk->sk_wmem_alloc))
  85                 printk(KERN_DEBUG "%s: wmem leakage (%d bytes) detected.\n",
  86                        __func__, refcount_read(&sk->sk_wmem_alloc));
  87 }
  88
  89 static void vcc_def_wakeup(struct sock *sk)
  90 {
  91         struct socket_wq *wq;
  92
  93         rcu_read_lock();
  94         wq = rcu_dereference(sk->sk_wq);
  95         if (skwq_has_sleeper(wq))
  96                 wake_up(&wq->wait);
  97         rcu_read_unlock();
  98 }
  99
 100 static inline int vcc_writable(struct sock *sk)
 101 {
 102         struct atm_vcc *vcc = atm_sk(sk);
 103
 104         return (vcc->qos.txtp.max_sdu +
 105                 refcount_read(&sk->sk_wmem_alloc)) <= sk->sk_sndbuf;
 106 }
 107
 108 static void vcc_write_space(struct sock *sk)
 109 {
 110         struct socket_wq *wq;
 111
 112         rcu_read_lock();
 113
 114         if (vcc_writable(sk)) {
 115                 wq = rcu_dereference(sk->sk_wq);
 116                 if (skwq_has_sleeper(wq))
 117                         wake_up_interruptible(&wq->wait);
 118
 119                 sk_wake_async_rcu(sk, SOCK_WAKE_SPACE, POLL_OUT);
 120         }
 121
 122         rcu_read_unlock();
 123 }
 124
 125 static void vcc_release_cb(struct sock *sk)
 126 {
 127         struct atm_vcc *vcc = atm_sk(sk);
 128
 129         if (vcc->release_cb)
 130                 vcc->release_cb(vcc);
 131 }
 132
 133 static struct proto vcc_proto = {
 134         .name     = "VCC",
 135         .owner    = THIS_MODULE,
 136         .obj_size = sizeof(struct atm_vcc),
 137         .release_cb = vcc_release_cb,
 138 };
 139
 140 int vcc_create(struct net *net, struct socket *sock, int protocol, int family, int kern)
 141 {
 142         struct sock *sk;
 143         struct atm_vcc *vcc;
 144
 145         sock->sk = NULL;
 146         if (sock->type == SOCK_STREAM)
 147                 return -EINVAL;
 148         sk = sk_alloc(net, family, GFP_KERNEL, &vcc_proto, kern);
 149         if (!sk)
 150                 return -ENOMEM;
 151         sock_init_data(sock, sk);
 152         sk->sk_state_change = vcc_def_wakeup;
 153         sk->sk_write_space = vcc_write_space;
 154
 155         vcc = atm_sk(sk);
 156         vcc->dev = NULL;
 157         memset(&vcc->local, 0, sizeof(struct sockaddr_atmsvc));
 158         memset(&vcc->remote, 0, sizeof(struct sockaddr_atmsvc));
 159         vcc->qos.txtp.max_sdu = 1 << 16; /* for meta VCs */
 160         refcount_set(&sk->sk_wmem_alloc, 1);
 161         atomic_set(&sk->sk_rmem_alloc, 0);
 162         vcc->push = NULL;
 163         vcc->pop = NULL;
 164         vcc->owner = NULL;
 165         vcc->push_oam = NULL;
 166         vcc->release_cb = NULL;
 167         vcc->vpi = vcc->vci = 0; /* no VCI/VPI yet */
 168         vcc->atm_options = vcc->aal_options = 0;
 169         sk->sk_destruct = vcc_sock_destruct;
 170         return 0;
 171 }
 172
 173 static void vcc_destroy_socket(struct sock *sk)
 174 {
 175         struct atm_vcc *vcc = atm_sk(sk);
 176         struct sk_buff *skb;
 177
 178         set_bit(ATM_VF_CLOSE, &vcc->flags);
 179         clear_bit(ATM_VF_READY, &vcc->flags);
 180         if (vcc->dev && vcc->dev->ops->close)
 181                 vcc->dev->ops->close(vcc);
 182         if (vcc->push)
 183                 vcc->push(vcc, NULL); /* atmarpd has no push */
 184         module_put(vcc->owner);
 185
 186         while ((skb = skb_dequeue(&sk->sk_receive_queue)) != NULL) {
 187                 atm_return(vcc, skb->truesize);
 188                 kfree_skb(skb);
 189         }
 190
 191         if (vcc->dev && vcc->dev->ops->owner) {
 192                 module_put(vcc->dev->ops->owner);
 193                 atm_dev_put(vcc->dev);
 194         }
 195
 196         vcc_remove_socket(sk);
 197 }
 198
 199 int vcc_release(struct socket *sock)
 200 {
 201         struct sock *sk = sock->sk;
 202
 203         if (sk) {
 204                 lock_sock(sk);
 205                 vcc_destroy_socket(sock->sk);
 206                 release_sock(sk);
 207                 sock_put(sk);
 208         }
 209
 210         return 0;
 211 }
 212
 213 void vcc_release_async(struct atm_vcc *vcc, int reply)
 214 {
 215         struct sock *sk = sk_atm(vcc);
 216
 217         set_bit(ATM_VF_CLOSE, &vcc->flags);
 218         sk->sk_shutdown |= RCV_SHUTDOWN;
 219         sk->sk_err = -reply;
 220         clear_bit(ATM_VF_WAITING, &vcc->flags);
 221         sk->sk_state_change(sk);
 222 }
 223 EXPORT_SYMBOL(vcc_release_async);
 224
 225 void vcc_process_recv_queue(struct atm_vcc *vcc)
 226 {
 227         struct sk_buff_head queue, *rq;
 228         struct sk_buff *skb, *tmp;
 229         unsigned long flags;
 230
 231         __skb_queue_head_init(&queue);
 232         rq = &sk_atm(vcc)->sk_receive_queue;
 233
 234         spin_lock_irqsave(&rq->lock, flags);
 235         skb_queue_splice_init(rq, &queue);
 236         spin_unlock_irqrestore(&rq->lock, flags);
 237
 238         skb_queue_walk_safe(&queue, skb, tmp) {
 239                 __skb_unlink(skb, &queue);
 240                 vcc->push(vcc, skb);
 241         }
 242 }
 243 EXPORT_SYMBOL(vcc_process_recv_queue);
 244
 245 void atm_dev_signal_change(struct atm_dev *dev, char signal)
 246 {
 247         pr_debug("%s signal=%d dev=%p number=%d dev->signal=%d\n",
 248                 __func__, signal, dev, dev->number, dev->signal);
 249
 250         /* atm driver sending invalid signal */
 251         WARN_ON(signal < ATM_PHY_SIG_LOST || signal > ATM_PHY_SIG_FOUND);
 252
 253         if (dev->signal == signal)
 254                 return; /* no change */
 255
 256         dev->signal = signal;
 257
 258         atomic_notifier_call_chain(&atm_dev_notify_chain, signal, dev);
 259 }
 260 EXPORT_SYMBOL(atm_dev_signal_change);
 261
 262 void atm_dev_release_vccs(struct atm_dev *dev)
 263 {
 264         int i;
 265
 266         write_lock_irq(&vcc_sklist_lock);
 267         for (i = 0; i < VCC_HTABLE_SIZE; i++) {
 268                 struct hlist_head *head = &vcc_hash[i];
 269                 struct hlist_node *tmp;
 270                 struct sock *s;
 271                 struct atm_vcc *vcc;
 272
 273                 sk_for_each_safe(s, tmp, head) {
 274                         vcc = atm_sk(s);
 275                         if (vcc->dev == dev) {
 276                                 vcc_release_async(vcc, -EPIPE);
 277                                 sk_del_node_init(s);
 278                         }
 279                 }
 280         }
 281         write_unlock_irq(&vcc_sklist_lock);
 282 }
 283 EXPORT_SYMBOL(atm_dev_release_vccs);
 284
 285 static int adjust_tp(struct atm_trafprm *tp, unsigned char aal)
 286 {
 287         int max_sdu;
 288
 289         if (!tp->traffic_class)
 290                 return 0;
 291         switch (aal) {
 292         case ATM_AAL0:
 293                 max_sdu = ATM_CELL_SIZE-1;
 294                 break;
 295         case ATM_AAL34:
 296                 max_sdu = ATM_MAX_AAL34_PDU;
 297                 break;
 298         default:
 299                 pr_warn("AAL problems ... (%d)\n", aal);
 300                 fallthrough;
 301         case ATM_AAL5:
 302                 max_sdu = ATM_MAX_AAL5_PDU;
 303         }
 304         if (!tp->max_sdu)
 305                 tp->max_sdu = max_sdu;
 306         else if (tp->max_sdu > max_sdu)
 307                 return -EINVAL;
 308         if (!tp->max_cdv)
 309                 tp->max_cdv = ATM_MAX_CDV;
 310         return 0;
 311 }
 312
 313 static int check_ci(const struct atm_vcc *vcc, short vpi, int vci)
 314 {
 315         struct hlist_head *head = &vcc_hash[vci & (VCC_HTABLE_SIZE - 1)];
 316         struct sock *s;
 317         struct atm_vcc *walk;
 318
 319         sk_for_each(s, head) {
 320                 walk = atm_sk(s);
 321                 if (walk->dev != vcc->dev)
 322                         continue;
 323                 if (test_bit(ATM_VF_ADDR, &walk->flags) && walk->vpi == vpi &&
 324                     walk->vci == vci && ((walk->qos.txtp.traffic_class !=
 325                     ATM_NONE && vcc->qos.txtp.traffic_class != ATM_NONE) ||
 326                     (walk->qos.rxtp.traffic_class != ATM_NONE &&
 327                     vcc->qos.rxtp.traffic_class != ATM_NONE)))
 328                         return -EADDRINUSE;
 329         }
 330
 331         /* allow VCCs with same VPI/VCI iff they don't collide on
 332            TX/RX (but we may refuse such sharing for other reasons,
 333            e.g. if protocol requires to have both channels) */
 334
 335         return 0;
 336 }
 337
 338 static int find_ci(const struct atm_vcc *vcc, short *vpi, int *vci)
 339 {
 340         static short p;        /* poor man's per-device cache */
 341         static int c;
 342         short old_p;
 343         int old_c;
 344         int err;
 345
 346         if (*vpi != ATM_VPI_ANY && *vci != ATM_VCI_ANY) {
 347                 err = check_ci(vcc, *vpi, *vci);
 348                 return err;
 349         }
 350         /* last scan may have left values out of bounds for current device */
 351         if (*vpi != ATM_VPI_ANY)
 352                 p = *vpi;
 353         else if (p >= 1 << vcc->dev->ci_range.vpi_bits)
 354                 p = 0;
 355         if (*vci != ATM_VCI_ANY)
 356                 c = *vci;
 357         else if (c < ATM_NOT_RSV_VCI || c >= 1 << vcc->dev->ci_range.vci_bits)
 358                         c = ATM_NOT_RSV_VCI;
 359         old_p = p;
 360         old_c = c;
 361         do {
 362                 if (!check_ci(vcc, p, c)) {
 363                         *vpi = p;
 364                         *vci = c;
 365                         return 0;
 366                 }
 367                 if (*vci == ATM_VCI_ANY) {
 368                         c++;
 369                         if (c >= 1 << vcc->dev->ci_range.vci_bits)
 370                                 c = ATM_NOT_RSV_VCI;
 371                 }
 372                 if ((c == ATM_NOT_RSV_VCI || *vci != ATM_VCI_ANY) &&
 373                     *vpi == ATM_VPI_ANY) {
 374                         p++;
 375                         if (p >= 1 << vcc->dev->ci_range.vpi_bits)
 376                                 p = 0;
 377                 }
 378         } while (old_p != p || old_c != c);
 379         return -EADDRINUSE;
 380 }
 381
 382 static int __vcc_connect(struct atm_vcc *vcc, struct atm_dev *dev, short vpi,
 383                          int vci)
 384 {
 385         struct sock *sk = sk_atm(vcc);
 386         int error;
 387
 388         if ((vpi != ATM_VPI_UNSPEC && vpi != ATM_VPI_ANY &&
 389             vpi >> dev->ci_range.vpi_bits) || (vci != ATM_VCI_UNSPEC &&
 390             vci != ATM_VCI_ANY && vci >> dev->ci_range.vci_bits))
 391                 return -EINVAL;
 392         if (vci > 0 && vci < ATM_NOT_RSV_VCI && !capable(CAP_NET_BIND_SERVICE))
 393                 return -EPERM;
 394         error = -ENODEV;
 395         if (!try_module_get(dev->ops->owner))
 396                 return error;
 397         vcc->dev = dev;
 398         write_lock_irq(&vcc_sklist_lock);
 399         if (test_bit(ATM_DF_REMOVED, &dev->flags) ||
 400             (error = find_ci(vcc, &vpi, &vci))) {
 401                 write_unlock_irq(&vcc_sklist_lock);
 402                 goto fail_module_put;
 403         }
 404         vcc->vpi = vpi;
 405         vcc->vci = vci;
 406         __vcc_insert_socket(sk);
 407         write_unlock_irq(&vcc_sklist_lock);
 408         switch (vcc->qos.aal) {
 409         case ATM_AAL0:
 410                 error = atm_init_aal0(vcc);
 411                 vcc->stats = &dev->stats.aal0;
 412                 break;
 413         case ATM_AAL34:
 414                 error = atm_init_aal34(vcc);
 415                 vcc->stats = &dev->stats.aal34;
 416                 break;
 417         case ATM_NO_AAL:
 418                 /* ATM_AAL5 is also used in the "0 for default" case */
 419                 vcc->qos.aal = ATM_AAL5;
 420                 fallthrough;
 421         case ATM_AAL5:
 422                 error = atm_init_aal5(vcc);
 423                 vcc->stats = &dev->stats.aal5;
 424                 break;
 425         default:
 426                 error = -EPROTOTYPE;
 427         }
 428         if (!error)
 429                 error = adjust_tp(&vcc->qos.txtp, vcc->qos.aal);
 430         if (!error)
 431                 error = adjust_tp(&vcc->qos.rxtp, vcc->qos.aal);
 432         if (error)
 433                 goto fail;
 434         pr_debug("VCC %d.%d, AAL %d\n", vpi, vci, vcc->qos.aal);
 435         pr_debug("  TX: %d, PCR %d..%d, SDU %d\n",
 436                  vcc->qos.txtp.traffic_class,
 437                  vcc->qos.txtp.min_pcr,
 438                  vcc->qos.txtp.max_pcr,
 439                  vcc->qos.txtp.max_sdu);
 440         pr_debug("  RX: %d, PCR %d..%d, SDU %d\n",
 441                  vcc->qos.rxtp.traffic_class,
 442                  vcc->qos.rxtp.min_pcr,
 443                  vcc->qos.rxtp.max_pcr,
 444                  vcc->qos.rxtp.max_sdu);
 445
 446         if (dev->ops->open) {
 447                 error = dev->ops->open(vcc);
 448                 if (error)
 449                         goto fail;
 450         }
 451         return 0;
 452
 453 fail:
 454         vcc_remove_socket(sk);
 455 fail_module_put:
 456         module_put(dev->ops->owner);
 457         /* ensure we get dev module ref count correct */
 458         vcc->dev = NULL;
 459         return error;
 460 }
 461
 462 int vcc_connect(struct socket *sock, int itf, short vpi, int vci)
 463 {
 464         struct atm_dev *dev;
 465         struct atm_vcc *vcc = ATM_SD(sock);
 466         int error;
 467
 468         pr_debug("(vpi %d, vci %d)\n", vpi, vci);
 469         if (sock->state == SS_CONNECTED)
 470                 return -EISCONN;
 471         if (sock->state != SS_UNCONNECTED)
 472                 return -EINVAL;
 473         if (!(vpi || vci))
 474                 return -EINVAL;
 475
 476         if (vpi != ATM_VPI_UNSPEC && vci != ATM_VCI_UNSPEC)
 477                 clear_bit(ATM_VF_PARTIAL, &vcc->flags);
 478         else
 479                 if (test_bit(ATM_VF_PARTIAL, &vcc->flags))
 480                         return -EINVAL;
 481         pr_debug("(TX: cl %d,bw %d-%d,sdu %d; "
 482                  "RX: cl %d,bw %d-%d,sdu %d,AAL %s%d)\n",
 483                  vcc->qos.txtp.traffic_class, vcc->qos.txtp.min_pcr,
 484                  vcc->qos.txtp.max_pcr, vcc->qos.txtp.max_sdu,
 485                  vcc->qos.rxtp.traffic_class, vcc->qos.rxtp.min_pcr,
 486                  vcc->qos.rxtp.max_pcr, vcc->qos.rxtp.max_sdu,
 487                  vcc->qos.aal == ATM_AAL5 ? "" :
 488                  vcc->qos.aal == ATM_AAL0 ? "" : " ??? code ",
 489                  vcc->qos.aal == ATM_AAL0 ? 0 : vcc->qos.aal);
 490         if (!test_bit(ATM_VF_HASQOS, &vcc->flags))
 491                 return -EBADFD;
 492         if (vcc->qos.txtp.traffic_class == ATM_ANYCLASS ||
 493             vcc->qos.rxtp.traffic_class == ATM_ANYCLASS)
 494                 return -EINVAL;
 495         if (likely(itf != ATM_ITF_ANY)) {
 496                 dev = try_then_request_module(atm_dev_lookup(itf),
 497                                               "atm-device-%d", itf);
 498         } else {
 499                 dev = NULL;
 500                 mutex_lock(&atm_dev_mutex);
 501                 if (!list_empty(&atm_devs)) {
 502                         dev = list_entry(atm_devs.next,
 503                                          struct atm_dev, dev_list);
 504                         atm_dev_hold(dev);
 505                 }
 506                 mutex_unlock(&atm_dev_mutex);
 507         }
 508         if (!dev)
 509                 return -ENODEV;
 510         error = __vcc_connect(vcc, dev, vpi, vci);
 511         if (error) {
 512                 atm_dev_put(dev);
 513                 return error;
 514         }
 515         if (vpi == ATM_VPI_UNSPEC || vci == ATM_VCI_UNSPEC)
 516                 set_bit(ATM_VF_PARTIAL, &vcc->flags);
 517         if (test_bit(ATM_VF_READY, &ATM_SD(sock)->flags))
 518                 sock->state = SS_CONNECTED;
 519         return 0;
 520 }
 521
 522 int vcc_recvmsg(struct socket *sock, struct msghdr *msg, size_t size,
 523                 int flags)
 524 {
 525         struct sock *sk = sock->sk;
 526         struct atm_vcc *vcc;
 527         struct sk_buff *skb;
 528         int copied, error = -EINVAL;
 529
 530         if (sock->state != SS_CONNECTED)
 531                 return -ENOTCONN;
 532
 533         /* only handle MSG_DONTWAIT and MSG_PEEK */
 534         if (flags & ~(MSG_DONTWAIT | MSG_PEEK))
 535                 return -EOPNOTSUPP;
 536
 537         vcc = ATM_SD(sock);
 538         if (test_bit(ATM_VF_RELEASED, &vcc->flags) ||
 539             test_bit(ATM_VF_CLOSE, &vcc->flags) ||
 540             !test_bit(ATM_VF_READY, &vcc->flags))
 541                 return 0;
 542
 543         skb = skb_recv_datagram(sk, flags, &error);
 544         if (!skb)
 545                 return error;
 546
 547         copied = skb->len;
 548         if (copied > size) {
 549                 copied = size;
 550                 msg->msg_flags |= MSG_TRUNC;
 551         }
 552
 553         error = skb_copy_datagram_msg(skb, 0, msg, copied);
 554         if (error)
 555                 return error;
 556         sock_recv_cmsgs(msg, sk, skb);
 557
 558         if (!(flags & MSG_PEEK)) {
 559                 pr_debug("%d -= %d\n", atomic_read(&sk->sk_rmem_alloc),
 560                          skb->truesize);
 561                 atm_return(vcc, skb->truesize);
 562         }
 563
 564         skb_free_datagram(sk, skb);
 565         return copied;
 566 }
 567
 568 int vcc_sendmsg(struct socket *sock, struct msghdr *m, size_t size)
 569 {
 570         struct sock *sk = sock->sk;
 571         DEFINE_WAIT(wait);
 572         struct atm_vcc *vcc;
 573         struct sk_buff *skb;
 574         int eff, error;
 575
 576         lock_sock(sk);
 577         if (sock->state != SS_CONNECTED) {
 578                 error = -ENOTCONN;
 579                 goto out;
 580         }
 581         if (m->msg_name) {
 582                 error = -EISCONN;
 583                 goto out;
 584         }
 585         vcc = ATM_SD(sock);
 586         if (test_bit(ATM_VF_RELEASED, &vcc->flags) ||
 587             test_bit(ATM_VF_CLOSE, &vcc->flags) ||
 588             !test_bit(ATM_VF_READY, &vcc->flags)) {
 589                 error = -EPIPE;
 590                 send_sig(SIGPIPE, current, 0);
 591                 goto out;
 592         }
 593         if (!size) {
 594                 error = 0;
 595                 goto out;
 596         }
 597         if (size > vcc->qos.txtp.max_sdu) {
 598                 error = -EMSGSIZE;
 599                 goto out;
 600         }
 601
 602         eff = (size+3) & ~3; /* align to word boundary */
 603         prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 604         error = 0;
 605         while (!vcc_tx_ready(vcc, eff)) {
 606                 if (m->msg_flags & MSG_DONTWAIT) {
 607                         error = -EAGAIN;
 608                         break;
 609                 }
 610                 schedule();
 611                 if (signal_pending(current)) {
 612                         error = -ERESTARTSYS;
 613                         break;
 614                 }
 615                 if (test_bit(ATM_VF_RELEASED, &vcc->flags) ||
 616                     test_bit(ATM_VF_CLOSE, &vcc->flags) ||
 617                     !test_bit(ATM_VF_READY, &vcc->flags)) {
 618                         error = -EPIPE;
 619                         send_sig(SIGPIPE, current, 0);
 620                         break;
 621                 }
 622                 prepare_to_wait(sk_sleep(sk), &wait, TASK_INTERRUPTIBLE);
 623         }
 624         finish_wait(sk_sleep(sk), &wait);
 625         if (error)
 626                 goto out;
 627
 628         skb = alloc_skb(eff, GFP_KERNEL);
 629         if (!skb) {
 630                 error = -ENOMEM;
 631                 goto out;
 632         }
 633         pr_debug("%d += %d\n", sk_wmem_alloc_get(sk), skb->truesize);
 634         atm_account_tx(vcc, skb);
 635
 636         skb->dev = NULL; /* for paths shared with net_device interfaces */
 637         if (!copy_from_iter_full(skb_put(skb, size), size, &m->msg_iter)) {
 638                 kfree_skb(skb);
 639                 error = -EFAULT;
 640                 goto out;
 641         }
 642         if (eff != size)
 643                 memset(skb->data + size, 0, eff-size);
 644         error = vcc->dev->ops->send(vcc, skb);
 645         error = error ? error : size;
 646 out:
 647         release_sock(sk);
 648         return error;
 649 }
 650
 651 __poll_t vcc_poll(struct file *file, struct socket *sock, poll_table *wait)
 652 {
 653         struct sock *sk = sock->sk;
 654         struct atm_vcc *vcc;
 655         __poll_t mask;
 656
 657         sock_poll_wait(file, sock, wait);
 658         mask = 0;
 659
 660         vcc = ATM_SD(sock);
 661
 662         /* exceptional events */
 663         if (sk->sk_err)
 664                 mask = EPOLLERR;
 665
 666         if (test_bit(ATM_VF_RELEASED, &vcc->flags) ||
 667             test_bit(ATM_VF_CLOSE, &vcc->flags))
 668                 mask |= EPOLLHUP;
 669
 670         /* readable? */
 671         if (!skb_queue_empty_lockless(&sk->sk_receive_queue))
 672                 mask |= EPOLLIN | EPOLLRDNORM;
 673
 674         /* writable? */
 675         if (sock->state == SS_CONNECTING &&
 676             test_bit(ATM_VF_WAITING, &vcc->flags))
 677                 return mask;
 678
 679         if (vcc->qos.txtp.traffic_class != ATM_NONE &&
 680             vcc_writable(sk))
 681                 mask |= EPOLLOUT | EPOLLWRNORM | EPOLLWRBAND;
 682
 683         return mask;
 684 }
 685
 686 static int atm_change_qos(struct atm_vcc *vcc, struct atm_qos *qos)
 687 {
 688         int error;
 689
 690         /*
 691          * Don't let the QoS change the already connected AAL type nor the
 692          * traffic class.
 693          */
 694         if (qos->aal != vcc->qos.aal ||
 695             qos->rxtp.traffic_class != vcc->qos.rxtp.traffic_class ||
 696             qos->txtp.traffic_class != vcc->qos.txtp.traffic_class)
 697                 return -EINVAL;
 698         error = adjust_tp(&qos->txtp, qos->aal);
 699         if (!error)
 700                 error = adjust_tp(&qos->rxtp, qos->aal);
 701         if (error)
 702                 return error;
 703         if (!vcc->dev->ops->change_qos)
 704                 return -EOPNOTSUPP;
 705         if (sk_atm(vcc)->sk_family == AF_ATMPVC)
 706                 return vcc->dev->ops->change_qos(vcc, qos, ATM_MF_SET);
 707         return svc_change_qos(vcc, qos);
 708 }
 709
 710 static int check_tp(const struct atm_trafprm *tp)
 711 {
 712         /* @@@ Should be merged with adjust_tp */
 713         if (!tp->traffic_class || tp->traffic_class == ATM_ANYCLASS)
 714                 return 0;
 715         if (tp->traffic_class != ATM_UBR && !tp->min_pcr && !tp->pcr &&
 716             !tp->max_pcr)
 717                 return -EINVAL;
 718         if (tp->min_pcr == ATM_MAX_PCR)
 719                 return -EINVAL;
 720         if (tp->min_pcr && tp->max_pcr && tp->max_pcr != ATM_MAX_PCR &&
 721             tp->min_pcr > tp->max_pcr)
 722                 return -EINVAL;
 723         /*
 724          * We allow pcr to be outside [min_pcr,max_pcr], because later
 725          * adjustment may still push it in the valid range.
 726          */
 727         return 0;
 728 }
 729
 730 static int check_qos(const struct atm_qos *qos)
 731 {
 732         int error;
 733
 734         if (!qos->txtp.traffic_class && !qos->rxtp.traffic_class)
 735                 return -EINVAL;
 736         if (qos->txtp.traffic_class != qos->rxtp.traffic_class &&
 737             qos->txtp.traffic_class && qos->rxtp.traffic_class &&
 738             qos->txtp.traffic_class != ATM_ANYCLASS &&
 739             qos->rxtp.traffic_class != ATM_ANYCLASS)
 740                 return -EINVAL;
 741         error = check_tp(&qos->txtp);
 742         if (error)
 743                 return error;
 744         return check_tp(&qos->rxtp);
 745 }
 746
 747 int vcc_setsockopt(struct socket *sock, int level, int optname,
 748                    sockptr_t optval, unsigned int optlen)
 749 {
 750         struct atm_vcc *vcc;
 751         unsigned long value;
 752         int error;
 753
 754         if (__SO_LEVEL_MATCH(optname, level) && optlen != __SO_SIZE(optname))
 755                 return -EINVAL;
 756
 757         vcc = ATM_SD(sock);
 758         switch (optname) {
 759         case SO_ATMQOS:
 760         {
 761                 struct atm_qos qos;
 762
 763                 if (copy_from_sockptr(&qos, optval, sizeof(qos)))
 764                         return -EFAULT;
 765                 error = check_qos(&qos);
 766                 if (error)
 767                         return error;
 768                 if (sock->state == SS_CONNECTED)
 769                         return atm_change_qos(vcc, &qos);
 770                 if (sock->state != SS_UNCONNECTED)
 771                         return -EBADFD;
 772                 vcc->qos = qos;
 773                 set_bit(ATM_VF_HASQOS, &vcc->flags);
 774                 return 0;
 775         }
 776         case SO_SETCLP:
 777                 if (copy_from_sockptr(&value, optval, sizeof(value)))
 778                         return -EFAULT;
 779                 if (value)
 780                         vcc->atm_options |= ATM_ATMOPT_CLP;
 781                 else
 782                         vcc->atm_options &= ~ATM_ATMOPT_CLP;
 783                 return 0;
 784         default:
 785                 return -EINVAL;
 786         }
 787 }
 788
 789 int vcc_getsockopt(struct socket *sock, int level, int optname,
 790                    char __user *optval, int __user *optlen)
 791 {
 792         struct atm_vcc *vcc;
 793         int len;
 794
 795         if (get_user(len, optlen))
 796                 return -EFAULT;
 797         if (__SO_LEVEL_MATCH(optname, level) && len != __SO_SIZE(optname))
 798                 return -EINVAL;
 799
 800         vcc = ATM_SD(sock);
 801         switch (optname) {
 802         case SO_ATMQOS:
 803                 if (!test_bit(ATM_VF_HASQOS, &vcc->flags))
 804                         return -EINVAL;
 805                 return copy_to_user(optval, &vcc->qos, sizeof(vcc->qos))
 806                         ? -EFAULT : 0;
 807         case SO_SETCLP:
 808                 return put_user(vcc->atm_options & ATM_ATMOPT_CLP ? 1 : 0,
 809                                 (unsigned long __user *)optval) ? -EFAULT : 0;
 810         case SO_ATMPVC:
 811         {
 812                 struct sockaddr_atmpvc pvc;
 813
 814                 if (!vcc->dev || !test_bit(ATM_VF_ADDR, &vcc->flags))
 815                         return -ENOTCONN;
 816                 memset(&pvc, 0, sizeof(pvc));
 817                 pvc.sap_family = AF_ATMPVC;
 818                 pvc.sap_addr.itf = vcc->dev->number;
 819                 pvc.sap_addr.vpi = vcc->vpi;
 820                 pvc.sap_addr.vci = vcc->vci;
 821                 return copy_to_user(optval, &pvc, sizeof(pvc)) ? -EFAULT : 0;
 822         }
 823         default:
 824                 return -EINVAL;
 825         }
 826 }
 827
 828 int register_atmdevice_notifier(struct notifier_block *nb)
 829 {
 830         return atomic_notifier_chain_register(&atm_dev_notify_chain, nb);
 831 }
 832 EXPORT_SYMBOL_GPL(register_atmdevice_notifier);
 833
 834 void unregister_atmdevice_notifier(struct notifier_block *nb)
 835 {
 836         atomic_notifier_chain_unregister(&atm_dev_notify_chain, nb);
 837 }
 838 EXPORT_SYMBOL_GPL(unregister_atmdevice_notifier);
 839
 840 static int __init atm_init(void)
 841 {
 842         int error;
 843
 844         error = proto_register(&vcc_proto, 0);
 845         if (error < 0)
 846                 goto out;
 847         error = atmpvc_init();
 848         if (error < 0) {
 849                 pr_err("atmpvc_init() failed with %d\n", error);
 850                 goto out_unregister_vcc_proto;
 851         }
 852         error = atmsvc_init();
 853         if (error < 0) {
 854                 pr_err("atmsvc_init() failed with %d\n", error);
 855                 goto out_atmpvc_exit;
 856         }
 857         error = atm_proc_init();
 858         if (error < 0) {
 859                 pr_err("atm_proc_init() failed with %d\n", error);
 860                 goto out_atmsvc_exit;
 861         }
 862         error = atm_sysfs_init();
 863         if (error < 0) {
 864                 pr_err("atm_sysfs_init() failed with %d\n", error);
 865                 goto out_atmproc_exit;
 866         }
 867 out:
 868         return error;
 869 out_atmproc_exit:
 870         atm_proc_exit();
 871 out_atmsvc_exit:
 872         atmsvc_exit();
 873 out_atmpvc_exit:
 874         atmsvc_exit();
 875 out_unregister_vcc_proto:
 876         proto_unregister(&vcc_proto);
 877         goto out;
 878 }
 879
 880 static void __exit atm_exit(void)
 881 {
 882         atm_proc_exit();
 883         atm_sysfs_exit();
 884         atmsvc_exit();
 885         atmpvc_exit();
 886         proto_unregister(&vcc_proto);
 887 }
 888
 889 subsys_initcall(atm_init);
 890
 891 module_exit(atm_exit);
 892
 893 MODULE_DESCRIPTION("Asynchronous Transfer Mode (ATM) networking core");
 894 MODULE_LICENSE("GPL");
 895 MODULE_ALIAS_NETPROTO(PF_ATMPVC);
 896 MODULE_ALIAS_NETPROTO(PF_ATMSVC);