kernel/vserver/network.c

   1 /*
   2  *  linux/kernel/vserver/network.c
   3  *
   4  *  Virtual Server: Network Support
   5  *
   6  *  Copyright (C) 2003-2006  Herbert Pötzl
   7  *
   8  *  V0.01  broken out from vcontext V0.05
   9  *  V0.02  cleaned up implementation
  10  *  V0.03  added equiv nx commands
  11  *  V0.04  switch to RCU based hash
  12  *  V0.05  and back to locking again
  13  *  V0.06  have __create claim() the nxi
  14  *
  15  */
  16
  17 #include <linux/slab.h>
  18 #include <linux/vserver/network_cmd.h>
  19 #include <linux/rcupdate.h>
  20 #include <net/tcp.h>
  21
  22 #include <asm/errno.h>
  23
  24
  25 /*      __alloc_nx_info()
  26
  27         * allocate an initialized nx_info struct
  28         * doesn't make it visible (hash)                        */
  29
  30 static struct nx_info *__alloc_nx_info(nid_t nid)
  31 {
  32         struct nx_info *new = NULL;
  33
  34         vxdprintk(VXD_CBIT(nid, 1), "alloc_nx_info(%d)*", nid);
  35
  36         /* would this benefit from a slab cache? */
  37         new = kmalloc(sizeof(struct nx_info), GFP_KERNEL);
  38         if (!new)
  39                 return 0;
  40
  41         memset (new, 0, sizeof(struct nx_info));
  42         new->nx_id = nid;
  43         INIT_HLIST_NODE(&new->nx_hlist);
  44         atomic_set(&new->nx_usecnt, 0);
  45         atomic_set(&new->nx_tasks, 0);
  46         new->nx_state = 0;
  47
  48         new->nx_flags = NXF_INIT_SET;
  49
  50         /* rest of init goes here */
  51
  52         vxdprintk(VXD_CBIT(nid, 0),
  53                 "alloc_nx_info(%d) = %p", nid, new);
  54         return new;
  55 }
  56
  57 /*      __dealloc_nx_info()
  58
  59         * final disposal of nx_info                             */
  60
  61 static void __dealloc_nx_info(struct nx_info *nxi)
  62 {
  63         vxdprintk(VXD_CBIT(nid, 0),
  64                 "dealloc_nx_info(%p)", nxi);
  65
  66         nxi->nx_hlist.next = LIST_POISON1;
  67         nxi->nx_id = -1;
  68
  69         BUG_ON(atomic_read(&nxi->nx_usecnt));
  70         BUG_ON(atomic_read(&nxi->nx_tasks));
  71
  72         nxi->nx_state |= NXS_RELEASED;
  73         kfree(nxi);
  74 }
  75
  76 static void __shutdown_nx_info(struct nx_info *nxi)
  77 {
  78         nxi->nx_state |= NXS_SHUTDOWN;
  79         vs_net_change(nxi, VSC_NETDOWN);
  80 }
  81
  82 /*      exported stuff                                          */
  83
  84 void free_nx_info(struct nx_info *nxi)
  85 {
  86         /* context shutdown is mandatory */
  87         BUG_ON(nxi->nx_state != NXS_SHUTDOWN);
  88
  89         /* context must not be hashed */
  90         BUG_ON(nxi->nx_state & NXS_HASHED);
  91
  92         BUG_ON(atomic_read(&nxi->nx_usecnt));
  93         BUG_ON(atomic_read(&nxi->nx_tasks));
  94
  95         __dealloc_nx_info(nxi);
  96 }
  97
  98
  99 /*      hash table for nx_info hash */
 100
 101 #define NX_HASH_SIZE    13
 102
 103 struct hlist_head nx_info_hash[NX_HASH_SIZE];
 104
 105 static spinlock_t nx_info_hash_lock = SPIN_LOCK_UNLOCKED;
 106
 107
 108 static inline unsigned int __hashval(nid_t nid)
 109 {
 110         return (nid % NX_HASH_SIZE);
 111 }
 112
 113
 114
 115 /*      __hash_nx_info()
 116
 117         * add the nxi to the global hash table
 118         * requires the hash_lock to be held                     */
 119
 120 static inline void __hash_nx_info(struct nx_info *nxi)
 121 {
 122         struct hlist_head *head;
 123
 124         vxd_assert_lock(&nx_info_hash_lock);
 125         vxdprintk(VXD_CBIT(nid, 4),
 126                 "__hash_nx_info: %p[#%d]", nxi, nxi->nx_id);
 127
 128         /* context must not be hashed */
 129         BUG_ON(nx_info_state(nxi, NXS_HASHED));
 130
 131         nxi->nx_state |= NXS_HASHED;
 132         head = &nx_info_hash[__hashval(nxi->nx_id)];
 133         hlist_add_head(&nxi->nx_hlist, head);
 134 }
 135
 136 /*      __unhash_nx_info()
 137
 138         * remove the nxi from the global hash table
 139         * requires the hash_lock to be held                     */
 140
 141 static inline void __unhash_nx_info(struct nx_info *nxi)
 142 {
 143         vxdprintk(VXD_CBIT(nid, 4),
 144                 "__unhash_nx_info: %p[#%d]", nxi, nxi->nx_id);
 145
 146         spin_lock(&nx_info_hash_lock);
 147         /* context must be hashed */
 148         BUG_ON(!nx_info_state(nxi, NXS_HASHED));
 149
 150         nxi->nx_state &= ~NXS_HASHED;
 151         hlist_del(&nxi->nx_hlist);
 152         spin_unlock(&nx_info_hash_lock);
 153 }
 154
 155
 156 /*      __lookup_nx_info()
 157
 158         * requires the hash_lock to be held
 159         * doesn't increment the nx_refcnt                       */
 160
 161 static inline struct nx_info *__lookup_nx_info(nid_t nid)
 162 {
 163         struct hlist_head *head = &nx_info_hash[__hashval(nid)];
 164         struct hlist_node *pos;
 165         struct nx_info *nxi;
 166
 167         vxd_assert_lock(&nx_info_hash_lock);
 168         hlist_for_each(pos, head) {
 169                 nxi = hlist_entry(pos, struct nx_info, nx_hlist);
 170
 171                 if (nxi->nx_id == nid)
 172                         goto found;
 173         }
 174         nxi = NULL;
 175 found:
 176         vxdprintk(VXD_CBIT(nid, 0),
 177                 "__lookup_nx_info(#%u): %p[#%u]",
 178                 nid, nxi, nxi?nxi->nx_id:0);
 179         return nxi;
 180 }
 181
 182
 183 /*      __nx_dynamic_id()
 184
 185         * find unused dynamic nid
 186         * requires the hash_lock to be held                     */
 187
 188 static inline nid_t __nx_dynamic_id(void)
 189 {
 190         static nid_t seq = MAX_N_CONTEXT;
 191         nid_t barrier = seq;
 192
 193         vxd_assert_lock(&nx_info_hash_lock);
 194         do {
 195                 if (++seq > MAX_N_CONTEXT)
 196                         seq = MIN_D_CONTEXT;
 197                 if (!__lookup_nx_info(seq)) {
 198                         vxdprintk(VXD_CBIT(nid, 4),
 199                                 "__nx_dynamic_id: [#%d]", seq);
 200                         return seq;
 201                 }
 202         } while (barrier != seq);
 203         return 0;
 204 }
 205
 206 /*      __create_nx_info()
 207
 208         * create the requested context
 209         * get(), claim() and hash it                            */
 210
 211 static struct nx_info * __create_nx_info(int id)
 212 {
 213         struct nx_info *new, *nxi = NULL;
 214
 215         vxdprintk(VXD_CBIT(nid, 1), "create_nx_info(%d)*", id);
 216
 217         if (!(new = __alloc_nx_info(id)))
 218                 return ERR_PTR(-ENOMEM);
 219
 220         /* required to make dynamic xids unique */
 221         spin_lock(&nx_info_hash_lock);
 222
 223         /* dynamic context requested */
 224         if (id == NX_DYNAMIC_ID) {
 225                 id = __nx_dynamic_id();
 226                 if (!id) {
 227                         printk(KERN_ERR "no dynamic context available.\n");
 228                         nxi = ERR_PTR(-EAGAIN);
 229                         goto out_unlock;
 230                 }
 231                 new->nx_id = id;
 232         }
 233         /* static context requested */
 234         else if ((nxi = __lookup_nx_info(id))) {
 235                 vxdprintk(VXD_CBIT(nid, 0),
 236                         "create_nx_info(%d) = %p (already there)", id, nxi);
 237                 if (nx_info_flags(nxi, NXF_STATE_SETUP, 0))
 238                         nxi = ERR_PTR(-EBUSY);
 239                 else
 240                         nxi = ERR_PTR(-EEXIST);
 241                 goto out_unlock;
 242         }
 243         /* dynamic nid creation blocker */
 244         else if (id >= MIN_D_CONTEXT) {
 245                 vxdprintk(VXD_CBIT(nid, 0),
 246                         "create_nx_info(%d) (dynamic rejected)", id);
 247                 nxi = ERR_PTR(-EINVAL);
 248                 goto out_unlock;
 249         }
 250
 251         /* new context */
 252         vxdprintk(VXD_CBIT(nid, 0),
 253                 "create_nx_info(%d) = %p (new)", id, new);
 254         claim_nx_info(new, NULL);
 255         __hash_nx_info(get_nx_info(new));
 256         nxi = new, new = NULL;
 257
 258 out_unlock:
 259         spin_unlock(&nx_info_hash_lock);
 260         if (new)
 261                 __dealloc_nx_info(new);
 262         return nxi;
 263 }
 264
 265
 266
 267 /*      exported stuff                                          */
 268
 269
 270 void unhash_nx_info(struct nx_info *nxi)
 271 {
 272         __shutdown_nx_info(nxi);
 273         __unhash_nx_info(nxi);
 274 }
 275
 276 #ifdef  CONFIG_VSERVER_LEGACYNET
 277
 278 struct nx_info *create_nx_info(void)
 279 {
 280         return __create_nx_info(NX_DYNAMIC_ID);
 281 }
 282
 283 #endif
 284
 285 /*      lookup_nx_info()
 286
 287         * search for a nx_info and get() it
 288         * negative id means current                             */
 289
 290 struct nx_info *lookup_nx_info(int id)
 291 {
 292         struct nx_info *nxi = NULL;
 293
 294         if (id < 0) {
 295                 nxi = get_nx_info(current->nx_info);
 296         } else if (id > 1) {
 297                 spin_lock(&nx_info_hash_lock);
 298                 nxi = get_nx_info(__lookup_nx_info(id));
 299                 spin_unlock(&nx_info_hash_lock);
 300         }
 301         return nxi;
 302 }
 303
 304 /*      nid_is_hashed()
 305
 306         * verify that nid is still hashed                       */
 307
 308 int nid_is_hashed(nid_t nid)
 309 {
 310         int hashed;
 311
 312         spin_lock(&nx_info_hash_lock);
 313         hashed = (__lookup_nx_info(nid) != NULL);
 314         spin_unlock(&nx_info_hash_lock);
 315         return hashed;
 316 }
 317
 318
 319 #ifdef  CONFIG_PROC_FS
 320
 321 int get_nid_list(int index, unsigned int *nids, int size)
 322 {
 323         int hindex, nr_nids = 0;
 324
 325         for (hindex = 0; hindex < NX_HASH_SIZE; hindex++) {
 326                 struct hlist_head *head = &nx_info_hash[hindex];
 327                 struct hlist_node *pos;
 328
 329                 spin_lock(&nx_info_hash_lock);
 330                 hlist_for_each(pos, head) {
 331                         struct nx_info *nxi;
 332
 333                         if (--index > 0)
 334                                 continue;
 335
 336                         nxi = hlist_entry(pos, struct nx_info, nx_hlist);
 337                         nids[nr_nids] = nxi->nx_id;
 338                         if (++nr_nids >= size) {
 339                                 spin_unlock(&nx_info_hash_lock);
 340                                 goto out;
 341                         }
 342                 }
 343                 /* keep the lock time short */
 344                 spin_unlock(&nx_info_hash_lock);
 345         }
 346 out:
 347         return nr_nids;
 348 }
 349 #endif
 350
 351
 352 /*
 353  *      migrate task to new network
 354  *      gets nxi, puts old_nxi on change
 355  */
 356
 357 int nx_migrate_task(struct task_struct *p, struct nx_info *nxi)
 358 {
 359         struct nx_info *old_nxi;
 360         int ret = 0;
 361
 362         if (!p || !nxi)
 363                 BUG();
 364
 365         vxdprintk(VXD_CBIT(nid, 5),
 366                 "nx_migrate_task(%p,%p[#%d.%d.%d])",
 367                 p, nxi, nxi->nx_id,
 368                 atomic_read(&nxi->nx_usecnt),
 369                 atomic_read(&nxi->nx_tasks));
 370
 371         /* maybe disallow this completely? */
 372         old_nxi = task_get_nx_info(p);
 373         if (old_nxi == nxi)
 374                 goto out;
 375
 376         task_lock(p);
 377         if (old_nxi)
 378                 clr_nx_info(&p->nx_info);
 379         claim_nx_info(nxi, p);
 380         set_nx_info(&p->nx_info, nxi);
 381         p->nid = nxi->nx_id;
 382         task_unlock(p);
 383
 384         vxdprintk(VXD_CBIT(nid, 5),
 385                 "moved task %p into nxi:%p[#%d]",
 386                 p, nxi, nxi->nx_id);
 387
 388         if (old_nxi)
 389                 release_nx_info(old_nxi, p);
 390         ret = 0;
 391 out:
 392         put_nx_info(old_nxi);
 393         return ret;
 394 }
 395
 396
 397 #ifdef CONFIG_INET
 398
 399 #include <linux/netdevice.h>
 400 #include <linux/inetdevice.h>
 401
 402 int ifa_in_nx_info(struct in_ifaddr *ifa, struct nx_info *nxi)
 403 {
 404         if (!nxi)
 405                 return 1;
 406         if (!ifa)
 407                 return 0;
 408         return addr_in_nx_info(nxi, ifa->ifa_local);
 409 }
 410
 411 int dev_in_nx_info(struct net_device *dev, struct nx_info *nxi)
 412 {
 413         struct in_device *in_dev;
 414         struct in_ifaddr **ifap;
 415         struct in_ifaddr *ifa;
 416         int ret = 0;
 417
 418         if (!nxi)
 419                 return 1;
 420
 421         in_dev = in_dev_get(dev);
 422         if (!in_dev)
 423                 goto out;
 424
 425         for (ifap = &in_dev->ifa_list; (ifa = *ifap) != NULL;
 426                 ifap = &ifa->ifa_next) {
 427                 if (addr_in_nx_info(nxi, ifa->ifa_local)) {
 428                         ret = 1;
 429                         break;
 430                 }
 431         }
 432         in_dev_put(in_dev);
 433 out:
 434         return ret;
 435 }
 436
 437 /*
 438  *      check if address is covered by socket
 439  *
 440  *      sk:     the socket to check against
 441  *      addr:   the address in question (must be != 0)
 442  */
 443 static inline int __addr_in_socket(struct sock *sk, uint32_t addr)
 444 {
 445         struct nx_info *nxi = sk->sk_nx_info;
 446         uint32_t saddr = inet_rcv_saddr(sk);
 447
 448         vxdprintk(VXD_CBIT(net, 5),
 449                 "__addr_in_socket(%p,%d.%d.%d.%d) %p:%d.%d.%d.%d %p;%lx",
 450                 sk, VXD_QUAD(addr), nxi, VXD_QUAD(saddr), sk->sk_socket,
 451                 (sk->sk_socket?sk->sk_socket->flags:0));
 452
 453         if (saddr) {
 454                 /* direct address match */
 455                 return (saddr == addr);
 456         } else if (nxi) {
 457                 /* match against nx_info */
 458                 return addr_in_nx_info(nxi, addr);
 459         } else {
 460                 /* unrestricted any socket */
 461                 return 1;
 462         }
 463 }
 464
 465
 466 int nx_addr_conflict(struct nx_info *nxi, uint32_t addr, struct sock *sk)
 467 {
 468         vxdprintk(VXD_CBIT(net, 2),
 469                 "nx_addr_conflict(%p,%p) %d.%d,%d.%d",
 470                 nxi, sk, VXD_QUAD(addr));
 471
 472         if (addr) {
 473                 /* check real address */
 474                 return __addr_in_socket(sk, addr);
 475         } else if (nxi) {
 476                 /* check against nx_info */
 477                 int i, n = nxi->nbipv4;
 478
 479                 for (i=0; i<n; i++)
 480                         if (__addr_in_socket(sk, nxi->ipv4[i]))
 481                                 return 1;
 482                 return 0;
 483         } else {
 484                 /* check against any */
 485                 return 1;
 486         }
 487 }
 488
 489 #endif /* CONFIG_INET */
 490
 491 void nx_set_persistent(struct nx_info *nxi)
 492 {
 493         vxdprintk(VXD_CBIT(nid, 6),
 494                 "nx_set_persistent(%p[#%d])", nxi, nxi->nx_id);
 495
 496         get_nx_info(nxi);
 497         claim_nx_info(nxi, NULL);
 498 }
 499
 500 void nx_clear_persistent(struct nx_info *nxi)
 501 {
 502         vxdprintk(VXD_CBIT(nid, 6),
 503                 "nx_clear_persistent(%p[#%d])", nxi, nxi->nx_id);
 504
 505         release_nx_info(nxi, NULL);
 506         put_nx_info(nxi);
 507 }
 508
 509 void nx_update_persistent(struct nx_info *nxi)
 510 {
 511         if (nx_info_flags(nxi, NXF_PERSISTENT, 0))
 512                 nx_set_persistent(nxi);
 513         else
 514                 nx_clear_persistent(nxi);
 515 }
 516
 517 /* vserver syscall commands below here */
 518
 519 /* taks nid and nx_info functions */
 520
 521 #include <asm/uaccess.h>
 522
 523
 524 int vc_task_nid(uint32_t id, void __user *data)
 525 {
 526         nid_t nid;
 527
 528         if (id) {
 529                 struct task_struct *tsk;
 530
 531                 if (!vx_check(0, VX_ADMIN|VX_WATCH))
 532                         return -EPERM;
 533
 534                 read_lock(&tasklist_lock);
 535                 tsk = find_task_by_real_pid(id);
 536                 nid = (tsk) ? tsk->nid : -ESRCH;
 537                 read_unlock(&tasklist_lock);
 538         }
 539         else
 540                 nid = nx_current_nid();
 541         return nid;
 542 }
 543
 544
 545 int vc_nx_info(uint32_t id, void __user *data)
 546 {
 547         struct nx_info *nxi;
 548         struct vcmd_nx_info_v0 vc_data;
 549
 550         if (!vx_check(0, VX_ADMIN))
 551                 return -ENOSYS;
 552         if (!capable(CAP_SYS_ADMIN) || !capable(CAP_SYS_RESOURCE))
 553                 return -EPERM;
 554
 555         nxi = lookup_nx_info(id);
 556         if (!nxi)
 557                 return -ESRCH;
 558
 559         vc_data.nid = nxi->nx_id;
 560         put_nx_info(nxi);
 561
 562         if (copy_to_user (data, &vc_data, sizeof(vc_data)))
 563                 return -EFAULT;
 564         return 0;
 565 }
 566
 567
 568 /* network functions */
 569
 570 int vc_net_create(uint32_t nid, void __user *data)
 571 {
 572         struct vcmd_net_create vc_data = { .flagword = NXF_INIT_SET };
 573         struct nx_info *new_nxi;
 574         int ret;
 575
 576         if (!capable(CAP_SYS_ADMIN))
 577                 return -EPERM;
 578         if (data && copy_from_user (&vc_data, data, sizeof(vc_data)))
 579                 return -EFAULT;
 580
 581         if ((nid > MAX_S_CONTEXT) && (nid != VX_DYNAMIC_ID))
 582                 return -EINVAL;
 583         if (nid < 2)
 584                 return -EINVAL;
 585
 586         new_nxi = __create_nx_info(nid);
 587         if (IS_ERR(new_nxi))
 588                 return PTR_ERR(new_nxi);
 589
 590         /* initial flags */
 591         new_nxi->nx_flags = vc_data.flagword;
 592
 593         ret = -ENOEXEC;
 594         if (vs_net_change(new_nxi, VSC_NETUP))
 595                 goto out;
 596
 597         ret = nx_migrate_task(current, new_nxi);
 598         if (ret)
 599                 goto out;
 600
 601         /* return context id on success */
 602         ret = new_nxi->nx_id;
 603
 604         /* get a reference for persistent contexts */
 605         if ((vc_data.flagword & NXF_PERSISTENT))
 606                 nx_set_persistent(new_nxi);
 607 out:
 608         release_nx_info(new_nxi, NULL);
 609         put_nx_info(new_nxi);
 610         return ret;
 611 }
 612
 613
 614 int vc_net_migrate(uint32_t id, void __user *data)
 615 {
 616         struct nx_info *nxi;
 617
 618         if (!capable(CAP_SYS_ADMIN))
 619                 return -EPERM;
 620
 621         nxi = lookup_nx_info(id);
 622         if (!nxi)
 623                 return -ESRCH;
 624         nx_migrate_task(current, nxi);
 625         put_nx_info(nxi);
 626         return 0;
 627 }
 628
 629 int vc_net_add(uint32_t nid, void __user *data)
 630 {
 631         struct vcmd_net_addr_v0 vc_data;
 632         struct nx_info *nxi;
 633         int index, pos, ret = 0;
 634
 635         if (!capable(CAP_SYS_ADMIN))
 636                 return -EPERM;
 637         if (data && copy_from_user (&vc_data, data, sizeof(vc_data)))
 638                 return -EFAULT;
 639
 640         switch (vc_data.type) {
 641         case NXA_TYPE_IPV4:
 642                 if ((vc_data.count < 1) || (vc_data.count > 4))
 643                         return -EINVAL;
 644                 break;
 645
 646         default:
 647                 break;
 648         }
 649
 650         nxi = lookup_nx_info(nid);
 651         if (!nxi)
 652                 return -ESRCH;
 653
 654         switch (vc_data.type) {
 655         case NXA_TYPE_IPV4:
 656                 index = 0;
 657                 while ((index < vc_data.count) &&
 658                         ((pos = nxi->nbipv4) < NB_IPV4ROOT)) {
 659                         nxi->ipv4[pos] = vc_data.ip[index];
 660                         nxi->mask[pos] = vc_data.mask[index];
 661                         index++;
 662                         nxi->nbipv4++;
 663                 }
 664                 ret = index;
 665                 break;
 666
 667         case NXA_TYPE_IPV4|NXA_MOD_BCAST:
 668                 nxi->v4_bcast = vc_data.ip[0];
 669                 ret = 1;
 670                 break;
 671
 672         default:
 673                 ret = -EINVAL;
 674                 break;
 675         }
 676
 677         put_nx_info(nxi);
 678         return ret;
 679 }
 680
 681 int vc_net_remove(uint32_t nid, void __user *data)
 682 {
 683         struct vcmd_net_addr_v0 vc_data;
 684         struct nx_info *nxi;
 685         int ret = 0;
 686
 687         if (!capable(CAP_SYS_ADMIN))
 688                 return -EPERM;
 689         if (data && copy_from_user (&vc_data, data, sizeof(vc_data)))
 690                 return -EFAULT;
 691
 692         nxi = lookup_nx_info(nid);
 693         if (!nxi)
 694                 return -ESRCH;
 695
 696         switch (vc_data.type) {
 697         case NXA_TYPE_ANY:
 698                 nxi->nbipv4 = 0;
 699                 break;
 700
 701         default:
 702                 ret = -EINVAL;
 703                 break;
 704         }
 705
 706         put_nx_info(nxi);
 707         return ret;
 708 }
 709
 710 int vc_get_nflags(uint32_t id, void __user *data)
 711 {
 712         struct nx_info *nxi;
 713         struct vcmd_net_flags_v0 vc_data;
 714
 715         if (!capable(CAP_SYS_ADMIN))
 716                 return -EPERM;
 717
 718         nxi = lookup_nx_info(id);
 719         if (!nxi)
 720                 return -ESRCH;
 721
 722         vc_data.flagword = nxi->nx_flags;
 723
 724         /* special STATE flag handling */
 725         vc_data.mask = vx_mask_flags(~0UL, nxi->nx_flags, NXF_ONE_TIME);
 726
 727         put_nx_info(nxi);
 728
 729         if (copy_to_user (data, &vc_data, sizeof(vc_data)))
 730                 return -EFAULT;
 731         return 0;
 732 }
 733
 734 int vc_set_nflags(uint32_t id, void __user *data)
 735 {
 736         struct nx_info *nxi;
 737         struct vcmd_net_flags_v0 vc_data;
 738         uint64_t mask, trigger;
 739
 740         if (!capable(CAP_SYS_ADMIN))
 741                 return -EPERM;
 742         if (copy_from_user (&vc_data, data, sizeof(vc_data)))
 743                 return -EFAULT;
 744
 745         nxi = lookup_nx_info(id);
 746         if (!nxi)
 747                 return -ESRCH;
 748
 749         /* special STATE flag handling */
 750         mask = vx_mask_mask(vc_data.mask, nxi->nx_flags, NXF_ONE_TIME);
 751         trigger = (mask & nxi->nx_flags) ^ (mask & vc_data.flagword);
 752
 753         nxi->nx_flags = vx_mask_flags(nxi->nx_flags,
 754                 vc_data.flagword, mask);
 755         if (trigger & NXF_PERSISTENT)
 756                 nx_update_persistent(nxi);
 757
 758         put_nx_info(nxi);
 759         return 0;
 760 }
 761
 762 int vc_get_ncaps(uint32_t id, void __user *data)
 763 {
 764         struct nx_info *nxi;
 765         struct vcmd_net_caps_v0 vc_data;
 766
 767         if (!capable(CAP_SYS_ADMIN))
 768                 return -EPERM;
 769
 770         nxi = lookup_nx_info(id);
 771         if (!nxi)
 772                 return -ESRCH;
 773
 774         vc_data.ncaps = nxi->nx_ncaps;
 775         vc_data.cmask = ~0UL;
 776         put_nx_info(nxi);
 777
 778         if (copy_to_user (data, &vc_data, sizeof(vc_data)))
 779                 return -EFAULT;
 780         return 0;
 781 }
 782
 783 int vc_set_ncaps(uint32_t id, void __user *data)
 784 {
 785         struct nx_info *nxi;
 786         struct vcmd_net_caps_v0 vc_data;
 787
 788         if (!capable(CAP_SYS_ADMIN))
 789                 return -EPERM;
 790         if (copy_from_user (&vc_data, data, sizeof(vc_data)))
 791                 return -EFAULT;
 792
 793         nxi = lookup_nx_info(id);
 794         if (!nxi)
 795                 return -ESRCH;
 796
 797         nxi->nx_ncaps = vx_mask_flags(nxi->nx_ncaps,
 798                 vc_data.ncaps, vc_data.cmask);
 799         put_nx_info(nxi);
 800         return 0;
 801 }
 802
 803
 804 #include <linux/module.h>
 805
 806 EXPORT_SYMBOL_GPL(free_nx_info);
 807 EXPORT_SYMBOL_GPL(unhash_nx_info);
 808