fs/nfs/nfs4client.c

   1 /*
   2  * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
   3  * Written by David Howells (dhowells@redhat.com)
   4  */
   5 #include <linux/module.h>
   6 #include <linux/nfs_fs.h>
   7 #include <linux/nfs_idmap.h>
   8 #include <linux/nfs_mount.h>
   9 #include <linux/sunrpc/addr.h>
  10 #include <linux/sunrpc/auth.h>
  11 #include <linux/sunrpc/xprt.h>
  12 #include <linux/sunrpc/bc_xprt.h>
  13 #include "internal.h"
  14 #include "callback.h"
  15 #include "delegation.h"
  16 #include "nfs4session.h"
  17 #include "pnfs.h"
  18 #include "netns.h"
  19
  20 #define NFSDBG_FACILITY         NFSDBG_CLIENT
  21
  22 /*
  23  * Get a unique NFSv4.0 callback identifier which will be used
  24  * by the V4.0 callback service to lookup the nfs_client struct
  25  */
  26 static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
  27 {
  28         int ret = 0;
  29         struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
  30
  31         if (clp->rpc_ops->version != 4 || minorversion != 0)
  32                 return ret;
  33         idr_preload(GFP_KERNEL);
  34         spin_lock(&nn->nfs_client_lock);
  35         ret = idr_alloc(&nn->cb_ident_idr, clp, 0, 0, GFP_NOWAIT);
  36         if (ret >= 0)
  37                 clp->cl_cb_ident = ret;
  38         spin_unlock(&nn->nfs_client_lock);
  39         idr_preload_end();
  40         return ret < 0 ? ret : 0;
  41 }
  42
  43 #ifdef CONFIG_NFS_V4_1
  44 /**
  45  * Per auth flavor data server rpc clients
  46  */
  47 struct nfs4_ds_server {
  48         struct list_head        list;   /* ds_clp->cl_ds_clients */
  49         struct rpc_clnt         *rpc_clnt;
  50 };
  51
  52 /**
  53  * Common lookup case for DS I/O
  54  */
  55 static struct nfs4_ds_server *
  56 nfs4_find_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
  57 {
  58         struct nfs4_ds_server *dss;
  59
  60         rcu_read_lock();
  61         list_for_each_entry_rcu(dss, &ds_clp->cl_ds_clients, list) {
  62                 if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
  63                         continue;
  64                 goto out;
  65         }
  66         dss = NULL;
  67 out:
  68         rcu_read_unlock();
  69         return dss;
  70 }
  71
  72 static struct nfs4_ds_server *
  73 nfs4_add_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor,
  74                            struct nfs4_ds_server *new)
  75 {
  76         struct nfs4_ds_server *dss;
  77
  78         spin_lock(&ds_clp->cl_lock);
  79         list_for_each_entry(dss, &ds_clp->cl_ds_clients, list) {
  80                 if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
  81                         continue;
  82                 goto out;
  83         }
  84         if (new)
  85                 list_add_rcu(&new->list, &ds_clp->cl_ds_clients);
  86         dss = new;
  87 out:
  88         spin_unlock(&ds_clp->cl_lock); /* need some lock to protect list */
  89         return dss;
  90 }
  91
  92 static struct nfs4_ds_server *
  93 nfs4_alloc_ds_server(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
  94 {
  95         struct nfs4_ds_server *dss;
  96
  97         dss = kmalloc(sizeof(*dss), GFP_NOFS);
  98         if (dss == NULL)
  99                 return ERR_PTR(-ENOMEM);
 100
 101         dss->rpc_clnt = rpc_clone_client_set_auth(ds_clp->cl_rpcclient, flavor);
 102         if (IS_ERR(dss->rpc_clnt)) {
 103                 int err = PTR_ERR(dss->rpc_clnt);
 104                 kfree (dss);
 105                 return ERR_PTR(err);
 106         }
 107         INIT_LIST_HEAD(&dss->list);
 108
 109         return dss;
 110 }
 111
 112 static void
 113 nfs4_free_ds_server(struct nfs4_ds_server *dss)
 114 {
 115         rpc_release_client(dss->rpc_clnt);
 116         kfree(dss);
 117 }
 118
 119 /**
 120 * Find or create a DS rpc client with th MDS server rpc client auth flavor
 121 * in the nfs_client cl_ds_clients list.
 122 */
 123 struct rpc_clnt *
 124 nfs4_find_or_create_ds_client(struct nfs_client *ds_clp, struct inode *inode)
 125 {
 126         struct nfs4_ds_server *dss, *new;
 127         rpc_authflavor_t flavor = NFS_SERVER(inode)->client->cl_auth->au_flavor;
 128
 129         dss = nfs4_find_ds_client(ds_clp, flavor);
 130         if (dss != NULL)
 131                 goto out;
 132         new = nfs4_alloc_ds_server(ds_clp, flavor);
 133         if (IS_ERR(new))
 134                 return ERR_CAST(new);
 135         dss = nfs4_add_ds_client(ds_clp, flavor, new);
 136         if (dss != new)
 137                 nfs4_free_ds_server(new);
 138 out:
 139         return dss->rpc_clnt;
 140 }
 141 EXPORT_SYMBOL_GPL(nfs4_find_or_create_ds_client);
 142
 143 static void
 144 nfs4_shutdown_ds_clients(struct nfs_client *clp)
 145 {
 146         struct nfs4_ds_server *dss;
 147         LIST_HEAD(shutdown_list);
 148
 149         while (!list_empty(&clp->cl_ds_clients)) {
 150                 dss = list_entry(clp->cl_ds_clients.next,
 151                                         struct nfs4_ds_server, list);
 152                 list_del(&dss->list);
 153                 rpc_shutdown_client(dss->rpc_clnt);
 154                 kfree (dss);
 155         }
 156 }
 157
 158 void nfs41_shutdown_client(struct nfs_client *clp)
 159 {
 160         if (nfs4_has_session(clp)) {
 161                 nfs4_shutdown_ds_clients(clp);
 162                 nfs4_destroy_session(clp->cl_session);
 163                 nfs4_destroy_clientid(clp);
 164         }
 165
 166 }
 167 #endif  /* CONFIG_NFS_V4_1 */
 168
 169 void nfs40_shutdown_client(struct nfs_client *clp)
 170 {
 171         if (clp->cl_slot_tbl) {
 172                 nfs4_release_slot_table(clp->cl_slot_tbl);
 173                 kfree(clp->cl_slot_tbl);
 174         }
 175 }
 176
 177 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
 178 {
 179         int err;
 180         struct nfs_client *clp = nfs_alloc_client(cl_init);
 181         if (IS_ERR(clp))
 182                 return clp;
 183
 184         err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
 185         if (err)
 186                 goto error;
 187
 188         if (cl_init->minorversion > NFS4_MAX_MINOR_VERSION) {
 189                 err = -EINVAL;
 190                 goto error;
 191         }
 192
 193         spin_lock_init(&clp->cl_lock);
 194         INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
 195         INIT_LIST_HEAD(&clp->cl_ds_clients);
 196         rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
 197         clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
 198         clp->cl_minorversion = cl_init->minorversion;
 199         clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
 200         clp->cl_mig_gen = 1;
 201         return clp;
 202
 203 error:
 204         nfs_free_client(clp);
 205         return ERR_PTR(err);
 206 }
 207
 208 /*
 209  * Destroy the NFS4 callback service
 210  */
 211 static void nfs4_destroy_callback(struct nfs_client *clp)
 212 {
 213         if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
 214                 nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
 215 }
 216
 217 static void nfs4_shutdown_client(struct nfs_client *clp)
 218 {
 219         if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
 220                 nfs4_kill_renewd(clp);
 221         clp->cl_mvops->shutdown_client(clp);
 222         nfs4_destroy_callback(clp);
 223         if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
 224                 nfs_idmap_delete(clp);
 225
 226         rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
 227         kfree(clp->cl_serverowner);
 228         kfree(clp->cl_serverscope);
 229         kfree(clp->cl_implid);
 230 }
 231
 232 void nfs4_free_client(struct nfs_client *clp)
 233 {
 234         nfs4_shutdown_client(clp);
 235         nfs_free_client(clp);
 236 }
 237
 238 /*
 239  * Initialize the NFS4 callback service
 240  */
 241 static int nfs4_init_callback(struct nfs_client *clp)
 242 {
 243         int error;
 244
 245         if (clp->rpc_ops->version == 4) {
 246                 struct rpc_xprt *xprt;
 247
 248                 xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
 249
 250                 if (nfs4_has_session(clp)) {
 251                         error = xprt_setup_backchannel(xprt,
 252                                                 NFS41_BC_MIN_CALLBACKS);
 253                         if (error < 0)
 254                                 return error;
 255                 }
 256
 257                 error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
 258                 if (error < 0) {
 259                         dprintk("%s: failed to start callback. Error = %d\n",
 260                                 __func__, error);
 261                         return error;
 262                 }
 263                 __set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
 264         }
 265         return 0;
 266 }
 267
 268 /**
 269  * nfs40_init_client - nfs_client initialization tasks for NFSv4.0
 270  * @clp - nfs_client to initialize
 271  *
 272  * Returns zero on success, or a negative errno if some error occurred.
 273  */
 274 int nfs40_init_client(struct nfs_client *clp)
 275 {
 276         struct nfs4_slot_table *tbl;
 277         int ret;
 278
 279         tbl = kzalloc(sizeof(*tbl), GFP_NOFS);
 280         if (tbl == NULL)
 281                 return -ENOMEM;
 282
 283         ret = nfs4_setup_slot_table(tbl, NFS4_MAX_SLOT_TABLE,
 284                                         "NFSv4.0 transport Slot table");
 285         if (ret) {
 286                 kfree(tbl);
 287                 return ret;
 288         }
 289
 290         clp->cl_slot_tbl = tbl;
 291         return 0;
 292 }
 293
 294 #if defined(CONFIG_NFS_V4_1)
 295
 296 /**
 297  * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
 298  * @clp - nfs_client to initialize
 299  *
 300  * Returns zero on success, or a negative errno if some error occurred.
 301  */
 302 int nfs41_init_client(struct nfs_client *clp)
 303 {
 304         struct nfs4_session *session = NULL;
 305
 306         /*
 307          * Create the session and mark it expired.
 308          * When a SEQUENCE operation encounters the expired session
 309          * it will do session recovery to initialize it.
 310          */
 311         session = nfs4_alloc_session(clp);
 312         if (!session)
 313                 return -ENOMEM;
 314
 315         clp->cl_session = session;
 316
 317         /*
 318          * The create session reply races with the server back
 319          * channel probe. Mark the client NFS_CS_SESSION_INITING
 320          * so that the client back channel can find the
 321          * nfs_client struct
 322          */
 323         nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
 324         return 0;
 325 }
 326
 327 #endif  /* CONFIG_NFS_V4_1 */
 328
 329 /*
 330  * Initialize the minor version specific parts of an NFS4 client record
 331  */
 332 static int nfs4_init_client_minor_version(struct nfs_client *clp)
 333 {
 334         int ret;
 335
 336         ret = clp->cl_mvops->init_client(clp);
 337         if (ret)
 338                 return ret;
 339         return nfs4_init_callback(clp);
 340 }
 341
 342 /**
 343  * nfs4_init_client - Initialise an NFS4 client record
 344  *
 345  * @clp: nfs_client to initialise
 346  * @timeparms: timeout parameters for underlying RPC transport
 347  * @ip_addr: callback IP address in presentation format
 348  * @authflavor: authentication flavor for underlying RPC transport
 349  *
 350  * Returns pointer to an NFS client, or an ERR_PTR value.
 351  */
 352 struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 353                                     const struct rpc_timeout *timeparms,
 354                                     const char *ip_addr)
 355 {
 356         char buf[INET6_ADDRSTRLEN + 1];
 357         struct nfs_client *old;
 358         int error;
 359
 360         if (clp->cl_cons_state == NFS_CS_READY) {
 361                 /* the client is initialised already */
 362                 dprintk("<-- nfs4_init_client() = 0 [already %p]\n", clp);
 363                 return clp;
 364         }
 365
 366         /* Check NFS protocol revision and initialize RPC op vector */
 367         clp->rpc_ops = &nfs_v4_clientops;
 368
 369         if (clp->cl_minorversion != 0)
 370                 __set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
 371         __set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
 372         __set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
 373         error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_GSS_KRB5I);
 374         if (error == -EINVAL)
 375                 error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX);
 376         if (error < 0)
 377                 goto error;
 378
 379         /* If no clientaddr= option was specified, find a usable cb address */
 380         if (ip_addr == NULL) {
 381                 struct sockaddr_storage cb_addr;
 382                 struct sockaddr *sap = (struct sockaddr *)&cb_addr;
 383
 384                 error = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
 385                 if (error < 0)
 386                         goto error;
 387                 error = rpc_ntop(sap, buf, sizeof(buf));
 388                 if (error < 0)
 389                         goto error;
 390                 ip_addr = (const char *)buf;
 391         }
 392         strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
 393
 394         error = nfs_idmap_new(clp);
 395         if (error < 0) {
 396                 dprintk("%s: failed to create idmapper. Error = %d\n",
 397                         __func__, error);
 398                 goto error;
 399         }
 400         __set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
 401
 402         error = nfs4_init_client_minor_version(clp);
 403         if (error < 0)
 404                 goto error;
 405
 406         if (!nfs4_has_session(clp))
 407                 nfs_mark_client_ready(clp, NFS_CS_READY);
 408
 409         error = nfs4_discover_server_trunking(clp, &old);
 410         if (error < 0)
 411                 goto error;
 412         nfs_put_client(clp);
 413         if (clp != old) {
 414                 clp->cl_preserve_clid = true;
 415                 clp = old;
 416         }
 417
 418         return clp;
 419
 420 error:
 421         nfs_mark_client_ready(clp, error);
 422         nfs_put_client(clp);
 423         dprintk("<-- nfs4_init_client() = xerror %d\n", error);
 424         return ERR_PTR(error);
 425 }
 426
 427 /*
 428  * SETCLIENTID just did a callback update with the callback ident in
 429  * "drop," but server trunking discovery claims "drop" and "keep" are
 430  * actually the same server.  Swap the callback IDs so that "keep"
 431  * will continue to use the callback ident the server now knows about,
 432  * and so that "keep"'s original callback ident is destroyed when
 433  * "drop" is freed.
 434  */
 435 static void nfs4_swap_callback_idents(struct nfs_client *keep,
 436                                       struct nfs_client *drop)
 437 {
 438         struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
 439         unsigned int save = keep->cl_cb_ident;
 440
 441         if (keep->cl_cb_ident == drop->cl_cb_ident)
 442                 return;
 443
 444         dprintk("%s: keeping callback ident %u and dropping ident %u\n",
 445                 __func__, keep->cl_cb_ident, drop->cl_cb_ident);
 446
 447         spin_lock(&nn->nfs_client_lock);
 448
 449         idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
 450         keep->cl_cb_ident = drop->cl_cb_ident;
 451
 452         idr_replace(&nn->cb_ident_idr, drop, save);
 453         drop->cl_cb_ident = save;
 454
 455         spin_unlock(&nn->nfs_client_lock);
 456 }
 457
 458 /**
 459  * nfs40_walk_client_list - Find server that recognizes a client ID
 460  *
 461  * @new: nfs_client with client ID to test
 462  * @result: OUT: found nfs_client, or new
 463  * @cred: credential to use for trunking test
 464  *
 465  * Returns zero, a negative errno, or a negative NFS4ERR status.
 466  * If zero is returned, an nfs_client pointer is planted in "result."
 467  *
 468  * NB: nfs40_walk_client_list() relies on the new nfs_client being
 469  *     the last nfs_client on the list.
 470  */
 471 int nfs40_walk_client_list(struct nfs_client *new,
 472                            struct nfs_client **result,
 473                            struct rpc_cred *cred)
 474 {
 475         struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 476         struct nfs_client *pos, *prev = NULL;
 477         struct nfs4_setclientid_res clid = {
 478                 .clientid       = new->cl_clientid,
 479                 .confirm        = new->cl_confirm,
 480         };
 481         int status = -NFS4ERR_STALE_CLIENTID;
 482
 483         spin_lock(&nn->nfs_client_lock);
 484         list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 485                 /* If "pos" isn't marked ready, we can't trust the
 486                  * remaining fields in "pos" */
 487                 if (pos->cl_cons_state > NFS_CS_READY) {
 488                         atomic_inc(&pos->cl_count);
 489                         spin_unlock(&nn->nfs_client_lock);
 490
 491                         if (prev)
 492                                 nfs_put_client(prev);
 493                         prev = pos;
 494
 495                         status = nfs_wait_client_init_complete(pos);
 496                         spin_lock(&nn->nfs_client_lock);
 497                         if (status < 0)
 498                                 continue;
 499                 }
 500                 if (pos->cl_cons_state != NFS_CS_READY)
 501                         continue;
 502
 503                 if (pos->rpc_ops != new->rpc_ops)
 504                         continue;
 505
 506                 if (pos->cl_proto != new->cl_proto)
 507                         continue;
 508
 509                 if (pos->cl_minorversion != new->cl_minorversion)
 510                         continue;
 511
 512                 if (pos->cl_clientid != new->cl_clientid)
 513                         continue;
 514
 515                 atomic_inc(&pos->cl_count);
 516                 spin_unlock(&nn->nfs_client_lock);
 517
 518                 if (prev)
 519                         nfs_put_client(prev);
 520                 prev = pos;
 521
 522                 status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
 523                 switch (status) {
 524                 case -NFS4ERR_STALE_CLIENTID:
 525                         break;
 526                 case 0:
 527                         nfs4_swap_callback_idents(pos, new);
 528
 529                         prev = NULL;
 530                         *result = pos;
 531                         dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
 532                                 __func__, pos, atomic_read(&pos->cl_count));
 533                 default:
 534                         goto out;
 535                 }
 536
 537                 spin_lock(&nn->nfs_client_lock);
 538         }
 539         spin_unlock(&nn->nfs_client_lock);
 540
 541         /* No match found. The server lost our clientid */
 542 out:
 543         if (prev)
 544                 nfs_put_client(prev);
 545         dprintk("NFS: <-- %s status = %d\n", __func__, status);
 546         return status;
 547 }
 548
 549 #ifdef CONFIG_NFS_V4_1
 550 /*
 551  * Returns true if the client IDs match
 552  */
 553 static bool nfs4_match_clientids(struct nfs_client *a, struct nfs_client *b)
 554 {
 555         if (a->cl_clientid != b->cl_clientid) {
 556                 dprintk("NFS: --> %s client ID %llx does not match %llx\n",
 557                         __func__, a->cl_clientid, b->cl_clientid);
 558                 return false;
 559         }
 560         dprintk("NFS: --> %s client ID %llx matches %llx\n",
 561                 __func__, a->cl_clientid, b->cl_clientid);
 562         return true;
 563 }
 564
 565 /*
 566  * Returns true if the server owners match
 567  */
 568 static bool
 569 nfs4_match_serverowners(struct nfs_client *a, struct nfs_client *b)
 570 {
 571         struct nfs41_server_owner *o1 = a->cl_serverowner;
 572         struct nfs41_server_owner *o2 = b->cl_serverowner;
 573
 574         if (o1->minor_id != o2->minor_id) {
 575                 dprintk("NFS: --> %s server owner minor IDs do not match\n",
 576                         __func__);
 577                 return false;
 578         }
 579
 580         if (o1->major_id_sz != o2->major_id_sz)
 581                 goto out_major_mismatch;
 582         if (memcmp(o1->major_id, o2->major_id, o1->major_id_sz) != 0)
 583                 goto out_major_mismatch;
 584
 585         dprintk("NFS: --> %s server owners match\n", __func__);
 586         return true;
 587
 588 out_major_mismatch:
 589         dprintk("NFS: --> %s server owner major IDs do not match\n",
 590                 __func__);
 591         return false;
 592 }
 593
 594 /**
 595  * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
 596  *
 597  * @new: nfs_client with client ID to test
 598  * @result: OUT: found nfs_client, or new
 599  * @cred: credential to use for trunking test
 600  *
 601  * Returns zero, a negative errno, or a negative NFS4ERR status.
 602  * If zero is returned, an nfs_client pointer is planted in "result."
 603  *
 604  * NB: nfs41_walk_client_list() relies on the new nfs_client being
 605  *     the last nfs_client on the list.
 606  */
 607 int nfs41_walk_client_list(struct nfs_client *new,
 608                            struct nfs_client **result,
 609                            struct rpc_cred *cred)
 610 {
 611         struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 612         struct nfs_client *pos, *prev = NULL;
 613         int status = -NFS4ERR_STALE_CLIENTID;
 614
 615         spin_lock(&nn->nfs_client_lock);
 616         list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 617                 /* If "pos" isn't marked ready, we can't trust the
 618                  * remaining fields in "pos", especially the client
 619                  * ID and serverowner fields.  Wait for CREATE_SESSION
 620                  * to finish. */
 621                 if (pos->cl_cons_state > NFS_CS_READY) {
 622                         atomic_inc(&pos->cl_count);
 623                         spin_unlock(&nn->nfs_client_lock);
 624
 625                         if (prev)
 626                                 nfs_put_client(prev);
 627                         prev = pos;
 628
 629                         status = nfs_wait_client_init_complete(pos);
 630                         if (status == 0) {
 631                                 nfs4_schedule_lease_recovery(pos);
 632                                 status = nfs4_wait_clnt_recover(pos);
 633                         }
 634                         spin_lock(&nn->nfs_client_lock);
 635                         if (status < 0)
 636                                 continue;
 637                 }
 638                 if (pos->cl_cons_state != NFS_CS_READY)
 639                         continue;
 640
 641                 if (pos->rpc_ops != new->rpc_ops)
 642                         continue;
 643
 644                 if (pos->cl_proto != new->cl_proto)
 645                         continue;
 646
 647                 if (pos->cl_minorversion != new->cl_minorversion)
 648                         continue;
 649
 650                 if (!nfs4_match_clientids(pos, new))
 651                         continue;
 652
 653                 if (!nfs4_match_serverowners(pos, new))
 654                         continue;
 655
 656                 atomic_inc(&pos->cl_count);
 657                 *result = pos;
 658                 status = 0;
 659                 dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
 660                         __func__, pos, atomic_read(&pos->cl_count));
 661                 break;
 662         }
 663
 664         /* No matching nfs_client found. */
 665         spin_unlock(&nn->nfs_client_lock);
 666         dprintk("NFS: <-- %s status = %d\n", __func__, status);
 667         if (prev)
 668                 nfs_put_client(prev);
 669         return status;
 670 }
 671 #endif  /* CONFIG_NFS_V4_1 */
 672
 673 static void nfs4_destroy_server(struct nfs_server *server)
 674 {
 675         nfs_server_return_all_delegations(server);
 676         unset_pnfs_layoutdriver(server);
 677         nfs4_purge_state_owners(server);
 678 }
 679
 680 /*
 681  * NFSv4.0 callback thread helper
 682  *
 683  * Find a client by callback identifier
 684  */
 685 struct nfs_client *
 686 nfs4_find_client_ident(struct net *net, int cb_ident)
 687 {
 688         struct nfs_client *clp;
 689         struct nfs_net *nn = net_generic(net, nfs_net_id);
 690
 691         spin_lock(&nn->nfs_client_lock);
 692         clp = idr_find(&nn->cb_ident_idr, cb_ident);
 693         if (clp)
 694                 atomic_inc(&clp->cl_count);
 695         spin_unlock(&nn->nfs_client_lock);
 696         return clp;
 697 }
 698
 699 #if defined(CONFIG_NFS_V4_1)
 700 /* Common match routine for v4.0 and v4.1 callback services */
 701 static bool nfs4_cb_match_client(const struct sockaddr *addr,
 702                 struct nfs_client *clp, u32 minorversion)
 703 {
 704         struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 705
 706         /* Don't match clients that failed to initialise */
 707         if (!(clp->cl_cons_state == NFS_CS_READY ||
 708             clp->cl_cons_state == NFS_CS_SESSION_INITING))
 709                 return false;
 710
 711         smp_rmb();
 712
 713         /* Match the version and minorversion */
 714         if (clp->rpc_ops->version != 4 ||
 715             clp->cl_minorversion != minorversion)
 716                 return false;
 717
 718         /* Match only the IP address, not the port number */
 719         if (!nfs_sockaddr_match_ipaddr(addr, clap))
 720                 return false;
 721
 722         return true;
 723 }
 724
 725 /*
 726  * NFSv4.1 callback thread helper
 727  * For CB_COMPOUND calls, find a client by IP address, protocol version,
 728  * minorversion, and sessionID
 729  *
 730  * Returns NULL if no such client
 731  */
 732 struct nfs_client *
 733 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 734                            struct nfs4_sessionid *sid, u32 minorversion)
 735 {
 736         struct nfs_client *clp;
 737         struct nfs_net *nn = net_generic(net, nfs_net_id);
 738
 739         spin_lock(&nn->nfs_client_lock);
 740         list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 741                 if (nfs4_cb_match_client(addr, clp, minorversion) == false)
 742                         continue;
 743
 744                 if (!nfs4_has_session(clp))
 745                         continue;
 746
 747                 /* Match sessionid*/
 748                 if (memcmp(clp->cl_session->sess_id.data,
 749                     sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
 750                         continue;
 751
 752                 atomic_inc(&clp->cl_count);
 753                 spin_unlock(&nn->nfs_client_lock);
 754                 return clp;
 755         }
 756         spin_unlock(&nn->nfs_client_lock);
 757         return NULL;
 758 }
 759
 760 #else /* CONFIG_NFS_V4_1 */
 761
 762 struct nfs_client *
 763 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 764                            struct nfs4_sessionid *sid, u32 minorversion)
 765 {
 766         return NULL;
 767 }
 768 #endif /* CONFIG_NFS_V4_1 */
 769
 770 /*
 771  * Set up an NFS4 client
 772  */
 773 static int nfs4_set_client(struct nfs_server *server,
 774                 const char *hostname,
 775                 const struct sockaddr *addr,
 776                 const size_t addrlen,
 777                 const char *ip_addr,
 778                 rpc_authflavor_t authflavour,
 779                 int proto, const struct rpc_timeout *timeparms,
 780                 u32 minorversion, struct net *net)
 781 {
 782         struct nfs_client_initdata cl_init = {
 783                 .hostname = hostname,
 784                 .addr = addr,
 785                 .addrlen = addrlen,
 786                 .nfs_mod = &nfs_v4,
 787                 .proto = proto,
 788                 .minorversion = minorversion,
 789                 .net = net,
 790         };
 791         struct nfs_client *clp;
 792         int error;
 793
 794         dprintk("--> nfs4_set_client()\n");
 795
 796         if (server->flags & NFS_MOUNT_NORESVPORT)
 797                 set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 798         if (server->options & NFS_OPTION_MIGRATION)
 799                 set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
 800
 801         /* Allocate or find a client reference we can use */
 802         clp = nfs_get_client(&cl_init, timeparms, ip_addr, authflavour);
 803         if (IS_ERR(clp)) {
 804                 error = PTR_ERR(clp);
 805                 goto error;
 806         }
 807
 808         /*
 809          * Query for the lease time on clientid setup or renewal
 810          *
 811          * Note that this will be set on nfs_clients that were created
 812          * only for the DS role and did not set this bit, but now will
 813          * serve a dual role.
 814          */
 815         set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
 816
 817         server->nfs_client = clp;
 818         dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
 819         return 0;
 820 error:
 821         dprintk("<-- nfs4_set_client() = xerror %d\n", error);
 822         return error;
 823 }
 824
 825 /*
 826  * Set up a pNFS Data Server client.
 827  *
 828  * Return any existing nfs_client that matches server address,port,version
 829  * and minorversion.
 830  *
 831  * For a new nfs_client, use a soft mount (default), a low retrans and a
 832  * low timeout interval so that if a connection is lost, we retry through
 833  * the MDS.
 834  */
 835 struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
 836                 const struct sockaddr *ds_addr, int ds_addrlen,
 837                 int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans)
 838 {
 839         struct nfs_client_initdata cl_init = {
 840                 .addr = ds_addr,
 841                 .addrlen = ds_addrlen,
 842                 .nfs_mod = &nfs_v4,
 843                 .proto = ds_proto,
 844                 .minorversion = mds_clp->cl_minorversion,
 845                 .net = mds_clp->cl_net,
 846         };
 847         struct rpc_timeout ds_timeout;
 848         struct nfs_client *clp;
 849
 850         /*
 851          * Set an authflavor equual to the MDS value. Use the MDS nfs_client
 852          * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
 853          * (section 13.1 RFC 5661).
 854          */
 855         nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
 856         clp = nfs_get_client(&cl_init, &ds_timeout, mds_clp->cl_ipaddr,
 857                              mds_clp->cl_rpcclient->cl_auth->au_flavor);
 858
 859         dprintk("<-- %s %p\n", __func__, clp);
 860         return clp;
 861 }
 862 EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
 863
 864 /*
 865  * Session has been established, and the client marked ready.
 866  * Set the mount rsize and wsize with negotiated fore channel
 867  * attributes which will be bound checked in nfs_server_set_fsinfo.
 868  */
 869 static void nfs4_session_set_rwsize(struct nfs_server *server)
 870 {
 871 #ifdef CONFIG_NFS_V4_1
 872         struct nfs4_session *sess;
 873         u32 server_resp_sz;
 874         u32 server_rqst_sz;
 875
 876         if (!nfs4_has_session(server->nfs_client))
 877                 return;
 878         sess = server->nfs_client->cl_session;
 879         server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
 880         server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
 881
 882         if (server->rsize > server_resp_sz)
 883                 server->rsize = server_resp_sz;
 884         if (server->wsize > server_rqst_sz)
 885                 server->wsize = server_rqst_sz;
 886 #endif /* CONFIG_NFS_V4_1 */
 887 }
 888
 889 static int nfs4_server_common_setup(struct nfs_server *server,
 890                 struct nfs_fh *mntfh, bool auth_probe)
 891 {
 892         struct nfs_fattr *fattr;
 893         int error;
 894
 895         /* data servers support only a subset of NFSv4.1 */
 896         if (is_ds_only_client(server->nfs_client))
 897                 return -EPROTONOSUPPORT;
 898
 899         fattr = nfs_alloc_fattr();
 900         if (fattr == NULL)
 901                 return -ENOMEM;
 902
 903         /* We must ensure the session is initialised first */
 904         error = nfs4_init_session(server->nfs_client);
 905         if (error < 0)
 906                 goto out;
 907
 908         /* Set the basic capabilities */
 909         server->caps |= server->nfs_client->cl_mvops->init_caps;
 910         if (server->flags & NFS_MOUNT_NORDIRPLUS)
 911                         server->caps &= ~NFS_CAP_READDIRPLUS;
 912         /*
 913          * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
 914          * authentication.
 915          */
 916         if (nfs4_disable_idmapping &&
 917                         server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
 918                 server->caps |= NFS_CAP_UIDGID_NOMAP;
 919
 920
 921         /* Probe the root fh to retrieve its FSID and filehandle */
 922         error = nfs4_get_rootfh(server, mntfh, auth_probe);
 923         if (error < 0)
 924                 goto out;
 925
 926         dprintk("Server FSID: %llx:%llx\n",
 927                         (unsigned long long) server->fsid.major,
 928                         (unsigned long long) server->fsid.minor);
 929         nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
 930
 931         nfs4_session_set_rwsize(server);
 932
 933         error = nfs_probe_fsinfo(server, mntfh, fattr);
 934         if (error < 0)
 935                 goto out;
 936
 937         if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
 938                 server->namelen = NFS4_MAXNAMLEN;
 939
 940         nfs_server_insert_lists(server);
 941         server->mount_time = jiffies;
 942         server->destroy = nfs4_destroy_server;
 943 out:
 944         nfs_free_fattr(fattr);
 945         return error;
 946 }
 947
 948 /*
 949  * Create a version 4 volume record
 950  */
 951 static int nfs4_init_server(struct nfs_server *server,
 952                 struct nfs_parsed_mount_data *data)
 953 {
 954         struct rpc_timeout timeparms;
 955         int error;
 956
 957         dprintk("--> nfs4_init_server()\n");
 958
 959         nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
 960                         data->timeo, data->retrans);
 961
 962         /* Initialise the client representation from the mount data */
 963         server->flags = data->flags;
 964         server->options = data->options;
 965         server->auth_info = data->auth_info;
 966
 967         /* Use the first specified auth flavor. If this flavor isn't
 968          * allowed by the server, use the SECINFO path to try the
 969          * other specified flavors */
 970         if (data->auth_info.flavor_len >= 1)
 971                 data->selected_flavor = data->auth_info.flavors[0];
 972         else
 973                 data->selected_flavor = RPC_AUTH_UNIX;
 974
 975         /* Get a client record */
 976         error = nfs4_set_client(server,
 977                         data->nfs_server.hostname,
 978                         (const struct sockaddr *)&data->nfs_server.address,
 979                         data->nfs_server.addrlen,
 980                         data->client_address,
 981                         data->selected_flavor,
 982                         data->nfs_server.protocol,
 983                         &timeparms,
 984                         data->minorversion,
 985                         data->net);
 986         if (error < 0)
 987                 goto error;
 988
 989         if (data->rsize)
 990                 server->rsize = nfs_block_size(data->rsize, NULL);
 991         if (data->wsize)
 992                 server->wsize = nfs_block_size(data->wsize, NULL);
 993
 994         server->acregmin = data->acregmin * HZ;
 995         server->acregmax = data->acregmax * HZ;
 996         server->acdirmin = data->acdirmin * HZ;
 997         server->acdirmax = data->acdirmax * HZ;
 998
 999         server->port = data->nfs_server.port;
1000
1001         error = nfs_init_server_rpcclient(server, &timeparms,
1002                                           data->selected_flavor);
1003
1004 error:
1005         /* Done */
1006         dprintk("<-- nfs4_init_server() = %d\n", error);
1007         return error;
1008 }
1009
1010 /*
1011  * Create a version 4 volume record
1012  * - keyed on server and FSID
1013  */
1014 /*struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1015                                       struct nfs_fh *mntfh)*/
1016 struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
1017                                       struct nfs_subversion *nfs_mod)
1018 {
1019         struct nfs_server *server;
1020         bool auth_probe;
1021         int error;
1022
1023         dprintk("--> nfs4_create_server()\n");
1024
1025         server = nfs_alloc_server();
1026         if (!server)
1027                 return ERR_PTR(-ENOMEM);
1028
1029         auth_probe = mount_info->parsed->auth_info.flavor_len < 1;
1030
1031         /* set up the general RPC client */
1032         error = nfs4_init_server(server, mount_info->parsed);
1033         if (error < 0)
1034                 goto error;
1035
1036         error = nfs4_server_common_setup(server, mount_info->mntfh, auth_probe);
1037         if (error < 0)
1038                 goto error;
1039
1040         dprintk("<-- nfs4_create_server() = %p\n", server);
1041         return server;
1042
1043 error:
1044         nfs_free_server(server);
1045         dprintk("<-- nfs4_create_server() = error %d\n", error);
1046         return ERR_PTR(error);
1047 }
1048
1049 /*
1050  * Create an NFS4 referral server record
1051  */
1052 struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1053                                                struct nfs_fh *mntfh)
1054 {
1055         struct nfs_client *parent_client;
1056         struct nfs_server *server, *parent_server;
1057         bool auth_probe;
1058         int error;
1059
1060         dprintk("--> nfs4_create_referral_server()\n");
1061
1062         server = nfs_alloc_server();
1063         if (!server)
1064                 return ERR_PTR(-ENOMEM);
1065
1066         parent_server = NFS_SB(data->sb);
1067         parent_client = parent_server->nfs_client;
1068
1069         /* Initialise the client representation from the parent server */
1070         nfs_server_copy_userdata(server, parent_server);
1071
1072         /* Get a client representation.
1073          * Note: NFSv4 always uses TCP, */
1074         error = nfs4_set_client(server, data->hostname,
1075                                 data->addr,
1076                                 data->addrlen,
1077                                 parent_client->cl_ipaddr,
1078                                 data->authflavor,
1079                                 rpc_protocol(parent_server->client),
1080                                 parent_server->client->cl_timeout,
1081                                 parent_client->cl_mvops->minor_version,
1082                                 parent_client->cl_net);
1083         if (error < 0)
1084                 goto error;
1085
1086         error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
1087         if (error < 0)
1088                 goto error;
1089
1090         auth_probe = parent_server->auth_info.flavor_len < 1;
1091
1092         error = nfs4_server_common_setup(server, mntfh, auth_probe);
1093         if (error < 0)
1094                 goto error;
1095
1096         dprintk("<-- nfs_create_referral_server() = %p\n", server);
1097         return server;
1098
1099 error:
1100         nfs_free_server(server);
1101         dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
1102         return ERR_PTR(error);
1103 }
1104
1105 /*
1106  * Grab the destination's particulars, including lease expiry time.
1107  *
1108  * Returns zero if probe succeeded and retrieved FSID matches the FSID
1109  * we have cached.
1110  */
1111 static int nfs_probe_destination(struct nfs_server *server)
1112 {
1113         struct inode *inode = server->super->s_root->d_inode;
1114         struct nfs_fattr *fattr;
1115         int error;
1116
1117         fattr = nfs_alloc_fattr();
1118         if (fattr == NULL)
1119                 return -ENOMEM;
1120
1121         /* Sanity: the probe won't work if the destination server
1122          * does not recognize the migrated FH. */
1123         error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
1124
1125         nfs_free_fattr(fattr);
1126         return error;
1127 }
1128
1129 /**
1130  * nfs4_update_server - Move an nfs_server to a different nfs_client
1131  *
1132  * @server: represents FSID to be moved
1133  * @hostname: new end-point's hostname
1134  * @sap: new end-point's socket address
1135  * @salen: size of "sap"
1136  *
1137  * The nfs_server must be quiescent before this function is invoked.
1138  * Either its session is drained (NFSv4.1+), or its transport is
1139  * plugged and drained (NFSv4.0).
1140  *
1141  * Returns zero on success, or a negative errno value.
1142  */
1143 int nfs4_update_server(struct nfs_server *server, const char *hostname,
1144                        struct sockaddr *sap, size_t salen)
1145 {
1146         struct nfs_client *clp = server->nfs_client;
1147         struct rpc_clnt *clnt = server->client;
1148         struct xprt_create xargs = {
1149                 .ident          = clp->cl_proto,
1150                 .net            = &init_net,
1151                 .dstaddr        = sap,
1152                 .addrlen        = salen,
1153                 .servername     = hostname,
1154         };
1155         char buf[INET6_ADDRSTRLEN + 1];
1156         struct sockaddr_storage address;
1157         struct sockaddr *localaddr = (struct sockaddr *)&address;
1158         int error;
1159
1160         dprintk("--> %s: move FSID %llx:%llx to \"%s\")\n", __func__,
1161                         (unsigned long long)server->fsid.major,
1162                         (unsigned long long)server->fsid.minor,
1163                         hostname);
1164
1165         error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1166         if (error != 0) {
1167                 dprintk("<-- %s(): rpc_switch_client_transport returned %d\n",
1168                         __func__, error);
1169                 goto out;
1170         }
1171
1172         error = rpc_localaddr(clnt, localaddr, sizeof(address));
1173         if (error != 0) {
1174                 dprintk("<-- %s(): rpc_localaddr returned %d\n",
1175                         __func__, error);
1176                 goto out;
1177         }
1178
1179         error = -EAFNOSUPPORT;
1180         if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0) {
1181                 dprintk("<-- %s(): rpc_ntop returned %d\n",
1182                         __func__, error);
1183                 goto out;
1184         }
1185
1186         nfs_server_remove_lists(server);
1187         error = nfs4_set_client(server, hostname, sap, salen, buf,
1188                                 clp->cl_rpcclient->cl_auth->au_flavor,
1189                                 clp->cl_proto, clnt->cl_timeout,
1190                                 clp->cl_minorversion, clp->cl_net);
1191         nfs_put_client(clp);
1192         if (error != 0) {
1193                 nfs_server_insert_lists(server);
1194                 dprintk("<-- %s(): nfs4_set_client returned %d\n",
1195                         __func__, error);
1196                 goto out;
1197         }
1198
1199         if (server->nfs_client->cl_hostname == NULL)
1200                 server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1201         nfs_server_insert_lists(server);
1202
1203         error = nfs_probe_destination(server);
1204         if (error < 0)
1205                 goto out;
1206
1207         dprintk("<-- %s() succeeded\n", __func__);
1208
1209 out:
1210         return error;
1211 }