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 <linux/sunrpc/rpc_pipe_fs.h>
  14 #include "internal.h"
  15 #include "callback.h"
  16 #include "delegation.h"
  17 #include "nfs4session.h"
  18 #include "pnfs.h"
  19 #include "netns.h"
  20
  21 #define NFSDBG_FACILITY         NFSDBG_CLIENT
  22
  23 /*
  24  * Get a unique NFSv4.0 callback identifier which will be used
  25  * by the V4.0 callback service to lookup the nfs_client struct
  26  */
  27 static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
  28 {
  29         int ret = 0;
  30         struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
  31
  32         if (clp->rpc_ops->version != 4 || minorversion != 0)
  33                 return ret;
  34         idr_preload(GFP_KERNEL);
  35         spin_lock(&nn->nfs_client_lock);
  36         ret = idr_alloc(&nn->cb_ident_idr, clp, 0, 0, GFP_NOWAIT);
  37         if (ret >= 0)
  38                 clp->cl_cb_ident = ret;
  39         spin_unlock(&nn->nfs_client_lock);
  40         idr_preload_end();
  41         return ret < 0 ? ret : 0;
  42 }
  43
  44 #ifdef CONFIG_NFS_V4_1
  45 /**
  46  * Per auth flavor data server rpc clients
  47  */
  48 struct nfs4_ds_server {
  49         struct list_head        list;   /* ds_clp->cl_ds_clients */
  50         struct rpc_clnt         *rpc_clnt;
  51 };
  52
  53 /**
  54  * Common lookup case for DS I/O
  55  */
  56 static struct nfs4_ds_server *
  57 nfs4_find_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
  58 {
  59         struct nfs4_ds_server *dss;
  60
  61         rcu_read_lock();
  62         list_for_each_entry_rcu(dss, &ds_clp->cl_ds_clients, list) {
  63                 if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
  64                         continue;
  65                 goto out;
  66         }
  67         dss = NULL;
  68 out:
  69         rcu_read_unlock();
  70         return dss;
  71 }
  72
  73 static struct nfs4_ds_server *
  74 nfs4_add_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor,
  75                            struct nfs4_ds_server *new)
  76 {
  77         struct nfs4_ds_server *dss;
  78
  79         spin_lock(&ds_clp->cl_lock);
  80         list_for_each_entry(dss, &ds_clp->cl_ds_clients, list) {
  81                 if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
  82                         continue;
  83                 goto out;
  84         }
  85         if (new)
  86                 list_add_rcu(&new->list, &ds_clp->cl_ds_clients);
  87         dss = new;
  88 out:
  89         spin_unlock(&ds_clp->cl_lock); /* need some lock to protect list */
  90         return dss;
  91 }
  92
  93 static struct nfs4_ds_server *
  94 nfs4_alloc_ds_server(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
  95 {
  96         struct nfs4_ds_server *dss;
  97
  98         dss = kmalloc(sizeof(*dss), GFP_NOFS);
  99         if (dss == NULL)
 100                 return ERR_PTR(-ENOMEM);
 101
 102         dss->rpc_clnt = rpc_clone_client_set_auth(ds_clp->cl_rpcclient, flavor);
 103         if (IS_ERR(dss->rpc_clnt)) {
 104                 int err = PTR_ERR(dss->rpc_clnt);
 105                 kfree (dss);
 106                 return ERR_PTR(err);
 107         }
 108         INIT_LIST_HEAD(&dss->list);
 109
 110         return dss;
 111 }
 112
 113 static void
 114 nfs4_free_ds_server(struct nfs4_ds_server *dss)
 115 {
 116         rpc_release_client(dss->rpc_clnt);
 117         kfree(dss);
 118 }
 119
 120 /**
 121 * Find or create a DS rpc client with th MDS server rpc client auth flavor
 122 * in the nfs_client cl_ds_clients list.
 123 */
 124 struct rpc_clnt *
 125 nfs4_find_or_create_ds_client(struct nfs_client *ds_clp, struct inode *inode)
 126 {
 127         struct nfs4_ds_server *dss, *new;
 128         rpc_authflavor_t flavor = NFS_SERVER(inode)->client->cl_auth->au_flavor;
 129
 130         dss = nfs4_find_ds_client(ds_clp, flavor);
 131         if (dss != NULL)
 132                 goto out;
 133         new = nfs4_alloc_ds_server(ds_clp, flavor);
 134         if (IS_ERR(new))
 135                 return ERR_CAST(new);
 136         dss = nfs4_add_ds_client(ds_clp, flavor, new);
 137         if (dss != new)
 138                 nfs4_free_ds_server(new);
 139 out:
 140         return dss->rpc_clnt;
 141 }
 142 EXPORT_SYMBOL_GPL(nfs4_find_or_create_ds_client);
 143
 144 static void
 145 nfs4_shutdown_ds_clients(struct nfs_client *clp)
 146 {
 147         struct nfs4_ds_server *dss;
 148         LIST_HEAD(shutdown_list);
 149
 150         while (!list_empty(&clp->cl_ds_clients)) {
 151                 dss = list_entry(clp->cl_ds_clients.next,
 152                                         struct nfs4_ds_server, list);
 153                 list_del(&dss->list);
 154                 rpc_shutdown_client(dss->rpc_clnt);
 155                 kfree (dss);
 156         }
 157 }
 158
 159 void nfs41_shutdown_client(struct nfs_client *clp)
 160 {
 161         if (nfs4_has_session(clp)) {
 162                 nfs4_shutdown_ds_clients(clp);
 163                 nfs4_destroy_session(clp->cl_session);
 164                 nfs4_destroy_clientid(clp);
 165         }
 166
 167 }
 168 #endif  /* CONFIG_NFS_V4_1 */
 169
 170 void nfs40_shutdown_client(struct nfs_client *clp)
 171 {
 172         if (clp->cl_slot_tbl) {
 173                 nfs4_shutdown_slot_table(clp->cl_slot_tbl);
 174                 kfree(clp->cl_slot_tbl);
 175         }
 176 }
 177
 178 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
 179 {
 180         int err;
 181         struct nfs_client *clp = nfs_alloc_client(cl_init);
 182         if (IS_ERR(clp))
 183                 return clp;
 184
 185         err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
 186         if (err)
 187                 goto error;
 188
 189         if (cl_init->minorversion > NFS4_MAX_MINOR_VERSION) {
 190                 err = -EINVAL;
 191                 goto error;
 192         }
 193
 194         spin_lock_init(&clp->cl_lock);
 195         INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
 196         INIT_LIST_HEAD(&clp->cl_ds_clients);
 197         rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
 198         clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
 199         clp->cl_minorversion = cl_init->minorversion;
 200         clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
 201         clp->cl_mig_gen = 1;
 202         return clp;
 203
 204 error:
 205         nfs_free_client(clp);
 206         return ERR_PTR(err);
 207 }
 208
 209 /*
 210  * Destroy the NFS4 callback service
 211  */
 212 static void nfs4_destroy_callback(struct nfs_client *clp)
 213 {
 214         if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
 215                 nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
 216 }
 217
 218 static void nfs4_shutdown_client(struct nfs_client *clp)
 219 {
 220         if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
 221                 nfs4_kill_renewd(clp);
 222         clp->cl_mvops->shutdown_client(clp);
 223         nfs4_destroy_callback(clp);
 224         if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
 225                 nfs_idmap_delete(clp);
 226
 227         rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
 228         kfree(clp->cl_serverowner);
 229         kfree(clp->cl_serverscope);
 230         kfree(clp->cl_implid);
 231 }
 232
 233 void nfs4_free_client(struct nfs_client *clp)
 234 {
 235         nfs4_shutdown_client(clp);
 236         nfs_free_client(clp);
 237 }
 238
 239 /*
 240  * Initialize the NFS4 callback service
 241  */
 242 static int nfs4_init_callback(struct nfs_client *clp)
 243 {
 244         int error;
 245
 246         if (clp->rpc_ops->version == 4) {
 247                 struct rpc_xprt *xprt;
 248
 249                 xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
 250
 251                 if (nfs4_has_session(clp)) {
 252                         error = xprt_setup_backchannel(xprt,
 253                                                 NFS41_BC_MIN_CALLBACKS);
 254                         if (error < 0)
 255                                 return error;
 256                 }
 257
 258                 error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
 259                 if (error < 0) {
 260                         dprintk("%s: failed to start callback. Error = %d\n",
 261                                 __func__, error);
 262                         return error;
 263                 }
 264                 __set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
 265         }
 266         return 0;
 267 }
 268
 269 /**
 270  * nfs40_init_client - nfs_client initialization tasks for NFSv4.0
 271  * @clp - nfs_client to initialize
 272  *
 273  * Returns zero on success, or a negative errno if some error occurred.
 274  */
 275 int nfs40_init_client(struct nfs_client *clp)
 276 {
 277         struct nfs4_slot_table *tbl;
 278         int ret;
 279
 280         tbl = kzalloc(sizeof(*tbl), GFP_NOFS);
 281         if (tbl == NULL)
 282                 return -ENOMEM;
 283
 284         ret = nfs4_setup_slot_table(tbl, NFS4_MAX_SLOT_TABLE,
 285                                         "NFSv4.0 transport Slot table");
 286         if (ret) {
 287                 kfree(tbl);
 288                 return ret;
 289         }
 290
 291         clp->cl_slot_tbl = tbl;
 292         return 0;
 293 }
 294
 295 #if defined(CONFIG_NFS_V4_1)
 296
 297 /**
 298  * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
 299  * @clp - nfs_client to initialize
 300  *
 301  * Returns zero on success, or a negative errno if some error occurred.
 302  */
 303 int nfs41_init_client(struct nfs_client *clp)
 304 {
 305         struct nfs4_session *session = NULL;
 306
 307         /*
 308          * Create the session and mark it expired.
 309          * When a SEQUENCE operation encounters the expired session
 310          * it will do session recovery to initialize it.
 311          */
 312         session = nfs4_alloc_session(clp);
 313         if (!session)
 314                 return -ENOMEM;
 315
 316         clp->cl_session = session;
 317
 318         /*
 319          * The create session reply races with the server back
 320          * channel probe. Mark the client NFS_CS_SESSION_INITING
 321          * so that the client back channel can find the
 322          * nfs_client struct
 323          */
 324         nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
 325         return 0;
 326 }
 327
 328 #endif  /* CONFIG_NFS_V4_1 */
 329
 330 /*
 331  * Initialize the minor version specific parts of an NFS4 client record
 332  */
 333 static int nfs4_init_client_minor_version(struct nfs_client *clp)
 334 {
 335         int ret;
 336
 337         ret = clp->cl_mvops->init_client(clp);
 338         if (ret)
 339                 return ret;
 340         return nfs4_init_callback(clp);
 341 }
 342
 343 /**
 344  * nfs4_init_client - Initialise an NFS4 client record
 345  *
 346  * @clp: nfs_client to initialise
 347  * @timeparms: timeout parameters for underlying RPC transport
 348  * @ip_addr: callback IP address in presentation format
 349  * @authflavor: authentication flavor for underlying RPC transport
 350  *
 351  * Returns pointer to an NFS client, or an ERR_PTR value.
 352  */
 353 struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 354                                     const struct rpc_timeout *timeparms,
 355                                     const char *ip_addr)
 356 {
 357         char buf[INET6_ADDRSTRLEN + 1];
 358         struct nfs_client *old;
 359         int error;
 360
 361         if (clp->cl_cons_state == NFS_CS_READY) {
 362                 /* the client is initialised already */
 363                 dprintk("<-- nfs4_init_client() = 0 [already %p]\n", clp);
 364                 return clp;
 365         }
 366
 367         /* Check NFS protocol revision and initialize RPC op vector */
 368         clp->rpc_ops = &nfs_v4_clientops;
 369
 370         if (clp->cl_minorversion != 0)
 371                 __set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
 372         __set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
 373         __set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
 374
 375         error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_GSS_KRB5I);
 376         if (error == -EINVAL)
 377                 error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX);
 378         if (error < 0)
 379                 goto error;
 380
 381         /* If no clientaddr= option was specified, find a usable cb address */
 382         if (ip_addr == NULL) {
 383                 struct sockaddr_storage cb_addr;
 384                 struct sockaddr *sap = (struct sockaddr *)&cb_addr;
 385
 386                 error = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
 387                 if (error < 0)
 388                         goto error;
 389                 error = rpc_ntop(sap, buf, sizeof(buf));
 390                 if (error < 0)
 391                         goto error;
 392                 ip_addr = (const char *)buf;
 393         }
 394         strlcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
 395
 396         error = nfs_idmap_new(clp);
 397         if (error < 0) {
 398                 dprintk("%s: failed to create idmapper. Error = %d\n",
 399                         __func__, error);
 400                 goto error;
 401         }
 402         __set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
 403
 404         error = nfs4_init_client_minor_version(clp);
 405         if (error < 0)
 406                 goto error;
 407
 408         if (!nfs4_has_session(clp))
 409                 nfs_mark_client_ready(clp, NFS_CS_READY);
 410
 411         error = nfs4_discover_server_trunking(clp, &old);
 412         if (error < 0)
 413                 goto error;
 414
 415         if (clp != old)
 416                 clp->cl_preserve_clid = true;
 417         nfs_put_client(clp);
 418         return old;
 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                         if (status < 0)
 497                                 goto out;
 498                         status = -NFS4ERR_STALE_CLIENTID;
 499                         spin_lock(&nn->nfs_client_lock);
 500                 }
 501                 if (pos->cl_cons_state != NFS_CS_READY)
 502                         continue;
 503
 504                 if (pos->rpc_ops != new->rpc_ops)
 505                         continue;
 506
 507                 if (pos->cl_proto != new->cl_proto)
 508                         continue;
 509
 510                 if (pos->cl_minorversion != new->cl_minorversion)
 511                         continue;
 512
 513                 if (pos->cl_clientid != new->cl_clientid)
 514                         continue;
 515
 516                 atomic_inc(&pos->cl_count);
 517                 spin_unlock(&nn->nfs_client_lock);
 518
 519                 if (prev)
 520                         nfs_put_client(prev);
 521                 prev = pos;
 522
 523                 status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
 524                 switch (status) {
 525                 case -NFS4ERR_STALE_CLIENTID:
 526                         break;
 527                 case 0:
 528                         nfs4_swap_callback_idents(pos, new);
 529
 530                         prev = NULL;
 531                         *result = pos;
 532                         dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
 533                                 __func__, pos, atomic_read(&pos->cl_count));
 534                 default:
 535                         goto out;
 536                 }
 537
 538                 spin_lock(&nn->nfs_client_lock);
 539         }
 540         spin_unlock(&nn->nfs_client_lock);
 541
 542         /* No match found. The server lost our clientid */
 543 out:
 544         if (prev)
 545                 nfs_put_client(prev);
 546         dprintk("NFS: <-- %s status = %d\n", __func__, status);
 547         return status;
 548 }
 549
 550 #ifdef CONFIG_NFS_V4_1
 551 /*
 552  * Returns true if the client IDs match
 553  */
 554 static bool nfs4_match_clientids(struct nfs_client *a, struct nfs_client *b)
 555 {
 556         if (a->cl_clientid != b->cl_clientid) {
 557                 dprintk("NFS: --> %s client ID %llx does not match %llx\n",
 558                         __func__, a->cl_clientid, b->cl_clientid);
 559                 return false;
 560         }
 561         dprintk("NFS: --> %s client ID %llx matches %llx\n",
 562                 __func__, a->cl_clientid, b->cl_clientid);
 563         return true;
 564 }
 565
 566 /*
 567  * Returns true if the server owners match
 568  */
 569 static bool
 570 nfs4_match_serverowners(struct nfs_client *a, struct nfs_client *b)
 571 {
 572         struct nfs41_server_owner *o1 = a->cl_serverowner;
 573         struct nfs41_server_owner *o2 = b->cl_serverowner;
 574
 575         if (o1->minor_id != o2->minor_id) {
 576                 dprintk("NFS: --> %s server owner minor IDs do not match\n",
 577                         __func__);
 578                 return false;
 579         }
 580
 581         if (o1->major_id_sz != o2->major_id_sz)
 582                 goto out_major_mismatch;
 583         if (memcmp(o1->major_id, o2->major_id, o1->major_id_sz) != 0)
 584                 goto out_major_mismatch;
 585
 586         dprintk("NFS: --> %s server owners match\n", __func__);
 587         return true;
 588
 589 out_major_mismatch:
 590         dprintk("NFS: --> %s server owner major IDs do not match\n",
 591                 __func__);
 592         return false;
 593 }
 594
 595 /**
 596  * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
 597  *
 598  * @new: nfs_client with client ID to test
 599  * @result: OUT: found nfs_client, or new
 600  * @cred: credential to use for trunking test
 601  *
 602  * Returns zero, a negative errno, or a negative NFS4ERR status.
 603  * If zero is returned, an nfs_client pointer is planted in "result."
 604  *
 605  * NB: nfs41_walk_client_list() relies on the new nfs_client being
 606  *     the last nfs_client on the list.
 607  */
 608 int nfs41_walk_client_list(struct nfs_client *new,
 609                            struct nfs_client **result,
 610                            struct rpc_cred *cred)
 611 {
 612         struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 613         struct nfs_client *pos, *prev = NULL;
 614         int status = -NFS4ERR_STALE_CLIENTID;
 615
 616         spin_lock(&nn->nfs_client_lock);
 617         list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 618                 /* If "pos" isn't marked ready, we can't trust the
 619                  * remaining fields in "pos", especially the client
 620                  * ID and serverowner fields.  Wait for CREATE_SESSION
 621                  * to finish. */
 622                 if (pos->cl_cons_state > NFS_CS_READY) {
 623                         atomic_inc(&pos->cl_count);
 624                         spin_unlock(&nn->nfs_client_lock);
 625
 626                         if (prev)
 627                                 nfs_put_client(prev);
 628                         prev = pos;
 629
 630                         status = nfs_wait_client_init_complete(pos);
 631                         if (status == 0) {
 632                                 nfs4_schedule_lease_recovery(pos);
 633                                 status = nfs4_wait_clnt_recover(pos);
 634                         }
 635                         spin_lock(&nn->nfs_client_lock);
 636                         if (status < 0)
 637                                 break;
 638                         status = -NFS4ERR_STALE_CLIENTID;
 639                 }
 640                 if (pos->cl_cons_state != NFS_CS_READY)
 641                         continue;
 642
 643                 if (pos->rpc_ops != new->rpc_ops)
 644                         continue;
 645
 646                 if (pos->cl_proto != new->cl_proto)
 647                         continue;
 648
 649                 if (pos->cl_minorversion != new->cl_minorversion)
 650                         continue;
 651
 652                 if (!nfs4_match_clientids(pos, new))
 653                         continue;
 654
 655                 if (!nfs4_match_serverowners(pos, new))
 656                         continue;
 657
 658                 atomic_inc(&pos->cl_count);
 659                 *result = pos;
 660                 status = 0;
 661                 dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
 662                         __func__, pos, atomic_read(&pos->cl_count));
 663                 break;
 664         }
 665
 666         /* No matching nfs_client found. */
 667         spin_unlock(&nn->nfs_client_lock);
 668         dprintk("NFS: <-- %s status = %d\n", __func__, status);
 669         if (prev)
 670                 nfs_put_client(prev);
 671         return status;
 672 }
 673 #endif  /* CONFIG_NFS_V4_1 */
 674
 675 static void nfs4_destroy_server(struct nfs_server *server)
 676 {
 677         nfs_server_return_all_delegations(server);
 678         unset_pnfs_layoutdriver(server);
 679         nfs4_purge_state_owners(server);
 680 }
 681
 682 /*
 683  * NFSv4.0 callback thread helper
 684  *
 685  * Find a client by callback identifier
 686  */
 687 struct nfs_client *
 688 nfs4_find_client_ident(struct net *net, int cb_ident)
 689 {
 690         struct nfs_client *clp;
 691         struct nfs_net *nn = net_generic(net, nfs_net_id);
 692
 693         spin_lock(&nn->nfs_client_lock);
 694         clp = idr_find(&nn->cb_ident_idr, cb_ident);
 695         if (clp)
 696                 atomic_inc(&clp->cl_count);
 697         spin_unlock(&nn->nfs_client_lock);
 698         return clp;
 699 }
 700
 701 #if defined(CONFIG_NFS_V4_1)
 702 /* Common match routine for v4.0 and v4.1 callback services */
 703 static bool nfs4_cb_match_client(const struct sockaddr *addr,
 704                 struct nfs_client *clp, u32 minorversion)
 705 {
 706         struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 707
 708         /* Don't match clients that failed to initialise */
 709         if (!(clp->cl_cons_state == NFS_CS_READY ||
 710             clp->cl_cons_state == NFS_CS_SESSION_INITING))
 711                 return false;
 712
 713         smp_rmb();
 714
 715         /* Match the version and minorversion */
 716         if (clp->rpc_ops->version != 4 ||
 717             clp->cl_minorversion != minorversion)
 718                 return false;
 719
 720         /* Match only the IP address, not the port number */
 721         if (!nfs_sockaddr_match_ipaddr(addr, clap))
 722                 return false;
 723
 724         return true;
 725 }
 726
 727 /*
 728  * NFSv4.1 callback thread helper
 729  * For CB_COMPOUND calls, find a client by IP address, protocol version,
 730  * minorversion, and sessionID
 731  *
 732  * Returns NULL if no such client
 733  */
 734 struct nfs_client *
 735 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 736                            struct nfs4_sessionid *sid, u32 minorversion)
 737 {
 738         struct nfs_client *clp;
 739         struct nfs_net *nn = net_generic(net, nfs_net_id);
 740
 741         spin_lock(&nn->nfs_client_lock);
 742         list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 743                 if (nfs4_cb_match_client(addr, clp, minorversion) == false)
 744                         continue;
 745
 746                 if (!nfs4_has_session(clp))
 747                         continue;
 748
 749                 /* Match sessionid*/
 750                 if (memcmp(clp->cl_session->sess_id.data,
 751                     sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
 752                         continue;
 753
 754                 atomic_inc(&clp->cl_count);
 755                 spin_unlock(&nn->nfs_client_lock);
 756                 return clp;
 757         }
 758         spin_unlock(&nn->nfs_client_lock);
 759         return NULL;
 760 }
 761
 762 #else /* CONFIG_NFS_V4_1 */
 763
 764 struct nfs_client *
 765 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 766                            struct nfs4_sessionid *sid, u32 minorversion)
 767 {
 768         return NULL;
 769 }
 770 #endif /* CONFIG_NFS_V4_1 */
 771
 772 /*
 773  * Set up an NFS4 client
 774  */
 775 static int nfs4_set_client(struct nfs_server *server,
 776                 const char *hostname,
 777                 const struct sockaddr *addr,
 778                 const size_t addrlen,
 779                 const char *ip_addr,
 780                 rpc_authflavor_t authflavour,
 781                 int proto, const struct rpc_timeout *timeparms,
 782                 u32 minorversion, struct net *net)
 783 {
 784         struct nfs_client_initdata cl_init = {
 785                 .hostname = hostname,
 786                 .addr = addr,
 787                 .addrlen = addrlen,
 788                 .nfs_mod = &nfs_v4,
 789                 .proto = proto,
 790                 .minorversion = minorversion,
 791                 .net = net,
 792         };
 793         struct nfs_client *clp;
 794         int error;
 795
 796         dprintk("--> nfs4_set_client()\n");
 797
 798         if (server->flags & NFS_MOUNT_NORESVPORT)
 799                 set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 800         if (server->options & NFS_OPTION_MIGRATION)
 801                 set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
 802
 803         /* Allocate or find a client reference we can use */
 804         clp = nfs_get_client(&cl_init, timeparms, ip_addr, authflavour);
 805         if (IS_ERR(clp)) {
 806                 error = PTR_ERR(clp);
 807                 goto error;
 808         }
 809
 810         /*
 811          * Query for the lease time on clientid setup or renewal
 812          *
 813          * Note that this will be set on nfs_clients that were created
 814          * only for the DS role and did not set this bit, but now will
 815          * serve a dual role.
 816          */
 817         set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
 818
 819         server->nfs_client = clp;
 820         dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
 821         return 0;
 822 error:
 823         dprintk("<-- nfs4_set_client() = xerror %d\n", error);
 824         return error;
 825 }
 826
 827 /*
 828  * Set up a pNFS Data Server client.
 829  *
 830  * Return any existing nfs_client that matches server address,port,version
 831  * and minorversion.
 832  *
 833  * For a new nfs_client, use a soft mount (default), a low retrans and a
 834  * low timeout interval so that if a connection is lost, we retry through
 835  * the MDS.
 836  */
 837 struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
 838                 const struct sockaddr *ds_addr, int ds_addrlen,
 839                 int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans)
 840 {
 841         struct nfs_client_initdata cl_init = {
 842                 .addr = ds_addr,
 843                 .addrlen = ds_addrlen,
 844                 .nfs_mod = &nfs_v4,
 845                 .proto = ds_proto,
 846                 .minorversion = mds_clp->cl_minorversion,
 847                 .net = mds_clp->cl_net,
 848         };
 849         struct rpc_timeout ds_timeout;
 850         struct nfs_client *clp;
 851
 852         /*
 853          * Set an authflavor equual to the MDS value. Use the MDS nfs_client
 854          * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
 855          * (section 13.1 RFC 5661).
 856          */
 857         nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
 858         clp = nfs_get_client(&cl_init, &ds_timeout, mds_clp->cl_ipaddr,
 859                              mds_clp->cl_rpcclient->cl_auth->au_flavor);
 860
 861         dprintk("<-- %s %p\n", __func__, clp);
 862         return clp;
 863 }
 864 EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
 865
 866 /*
 867  * Session has been established, and the client marked ready.
 868  * Set the mount rsize and wsize with negotiated fore channel
 869  * attributes which will be bound checked in nfs_server_set_fsinfo.
 870  */
 871 static void nfs4_session_set_rwsize(struct nfs_server *server)
 872 {
 873 #ifdef CONFIG_NFS_V4_1
 874         struct nfs4_session *sess;
 875         u32 server_resp_sz;
 876         u32 server_rqst_sz;
 877
 878         if (!nfs4_has_session(server->nfs_client))
 879                 return;
 880         sess = server->nfs_client->cl_session;
 881         server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
 882         server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
 883
 884         if (server->rsize > server_resp_sz)
 885                 server->rsize = server_resp_sz;
 886         if (server->wsize > server_rqst_sz)
 887                 server->wsize = server_rqst_sz;
 888 #endif /* CONFIG_NFS_V4_1 */
 889 }
 890
 891 static int nfs4_server_common_setup(struct nfs_server *server,
 892                 struct nfs_fh *mntfh, bool auth_probe)
 893 {
 894         struct nfs_fattr *fattr;
 895         int error;
 896
 897         /* data servers support only a subset of NFSv4.1 */
 898         if (is_ds_only_client(server->nfs_client))
 899                 return -EPROTONOSUPPORT;
 900
 901         fattr = nfs_alloc_fattr();
 902         if (fattr == NULL)
 903                 return -ENOMEM;
 904
 905         /* We must ensure the session is initialised first */
 906         error = nfs4_init_session(server->nfs_client);
 907         if (error < 0)
 908                 goto out;
 909
 910         /* Set the basic capabilities */
 911         server->caps |= server->nfs_client->cl_mvops->init_caps;
 912         if (server->flags & NFS_MOUNT_NORDIRPLUS)
 913                         server->caps &= ~NFS_CAP_READDIRPLUS;
 914         /*
 915          * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
 916          * authentication.
 917          */
 918         if (nfs4_disable_idmapping &&
 919                         server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
 920                 server->caps |= NFS_CAP_UIDGID_NOMAP;
 921
 922
 923         /* Probe the root fh to retrieve its FSID and filehandle */
 924         error = nfs4_get_rootfh(server, mntfh, auth_probe);
 925         if (error < 0)
 926                 goto out;
 927
 928         dprintk("Server FSID: %llx:%llx\n",
 929                         (unsigned long long) server->fsid.major,
 930                         (unsigned long long) server->fsid.minor);
 931         nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
 932
 933         nfs4_session_set_rwsize(server);
 934
 935         error = nfs_probe_fsinfo(server, mntfh, fattr);
 936         if (error < 0)
 937                 goto out;
 938
 939         if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
 940                 server->namelen = NFS4_MAXNAMLEN;
 941
 942         nfs_server_insert_lists(server);
 943         server->mount_time = jiffies;
 944         server->destroy = nfs4_destroy_server;
 945 out:
 946         nfs_free_fattr(fattr);
 947         return error;
 948 }
 949
 950 /*
 951  * Create a version 4 volume record
 952  */
 953 static int nfs4_init_server(struct nfs_server *server,
 954                 struct nfs_parsed_mount_data *data)
 955 {
 956         struct rpc_timeout timeparms;
 957         int error;
 958
 959         dprintk("--> nfs4_init_server()\n");
 960
 961         nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
 962                         data->timeo, data->retrans);
 963
 964         /* Initialise the client representation from the mount data */
 965         server->flags = data->flags;
 966         server->options = data->options;
 967         server->auth_info = data->auth_info;
 968
 969         /* Use the first specified auth flavor. If this flavor isn't
 970          * allowed by the server, use the SECINFO path to try the
 971          * other specified flavors */
 972         if (data->auth_info.flavor_len >= 1)
 973                 data->selected_flavor = data->auth_info.flavors[0];
 974         else
 975                 data->selected_flavor = RPC_AUTH_UNIX;
 976
 977         /* Get a client record */
 978         error = nfs4_set_client(server,
 979                         data->nfs_server.hostname,
 980                         (const struct sockaddr *)&data->nfs_server.address,
 981                         data->nfs_server.addrlen,
 982                         data->client_address,
 983                         data->selected_flavor,
 984                         data->nfs_server.protocol,
 985                         &timeparms,
 986                         data->minorversion,
 987                         data->net);
 988         if (error < 0)
 989                 goto error;
 990
 991         if (data->rsize)
 992                 server->rsize = nfs_block_size(data->rsize, NULL);
 993         if (data->wsize)
 994                 server->wsize = nfs_block_size(data->wsize, NULL);
 995
 996         server->acregmin = data->acregmin * HZ;
 997         server->acregmax = data->acregmax * HZ;
 998         server->acdirmin = data->acdirmin * HZ;
 999         server->acdirmax = data->acdirmax * HZ;
1000
1001         server->port = data->nfs_server.port;
1002
1003         error = nfs_init_server_rpcclient(server, &timeparms,
1004                                           data->selected_flavor);
1005
1006 error:
1007         /* Done */
1008         dprintk("<-- nfs4_init_server() = %d\n", error);
1009         return error;
1010 }
1011
1012 /*
1013  * Create a version 4 volume record
1014  * - keyed on server and FSID
1015  */
1016 /*struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1017                                       struct nfs_fh *mntfh)*/
1018 struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
1019                                       struct nfs_subversion *nfs_mod)
1020 {
1021         struct nfs_server *server;
1022         bool auth_probe;
1023         int error;
1024
1025         dprintk("--> nfs4_create_server()\n");
1026
1027         server = nfs_alloc_server();
1028         if (!server)
1029                 return ERR_PTR(-ENOMEM);
1030
1031         auth_probe = mount_info->parsed->auth_info.flavor_len < 1;
1032
1033         /* set up the general RPC client */
1034         error = nfs4_init_server(server, mount_info->parsed);
1035         if (error < 0)
1036                 goto error;
1037
1038         error = nfs4_server_common_setup(server, mount_info->mntfh, auth_probe);
1039         if (error < 0)
1040                 goto error;
1041
1042         dprintk("<-- nfs4_create_server() = %p\n", server);
1043         return server;
1044
1045 error:
1046         nfs_free_server(server);
1047         dprintk("<-- nfs4_create_server() = error %d\n", error);
1048         return ERR_PTR(error);
1049 }
1050
1051 /*
1052  * Create an NFS4 referral server record
1053  */
1054 struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1055                                                struct nfs_fh *mntfh)
1056 {
1057         struct nfs_client *parent_client;
1058         struct nfs_server *server, *parent_server;
1059         bool auth_probe;
1060         int error;
1061
1062         dprintk("--> nfs4_create_referral_server()\n");
1063
1064         server = nfs_alloc_server();
1065         if (!server)
1066                 return ERR_PTR(-ENOMEM);
1067
1068         parent_server = NFS_SB(data->sb);
1069         parent_client = parent_server->nfs_client;
1070
1071         /* Initialise the client representation from the parent server */
1072         nfs_server_copy_userdata(server, parent_server);
1073
1074         /* Get a client representation.
1075          * Note: NFSv4 always uses TCP, */
1076         error = nfs4_set_client(server, data->hostname,
1077                                 data->addr,
1078                                 data->addrlen,
1079                                 parent_client->cl_ipaddr,
1080                                 data->authflavor,
1081                                 rpc_protocol(parent_server->client),
1082                                 parent_server->client->cl_timeout,
1083                                 parent_client->cl_mvops->minor_version,
1084                                 parent_client->cl_net);
1085         if (error < 0)
1086                 goto error;
1087
1088         error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
1089         if (error < 0)
1090                 goto error;
1091
1092         auth_probe = parent_server->auth_info.flavor_len < 1;
1093
1094         error = nfs4_server_common_setup(server, mntfh, auth_probe);
1095         if (error < 0)
1096                 goto error;
1097
1098         dprintk("<-- nfs_create_referral_server() = %p\n", server);
1099         return server;
1100
1101 error:
1102         nfs_free_server(server);
1103         dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
1104         return ERR_PTR(error);
1105 }
1106
1107 /*
1108  * Grab the destination's particulars, including lease expiry time.
1109  *
1110  * Returns zero if probe succeeded and retrieved FSID matches the FSID
1111  * we have cached.
1112  */
1113 static int nfs_probe_destination(struct nfs_server *server)
1114 {
1115         struct inode *inode = server->super->s_root->d_inode;
1116         struct nfs_fattr *fattr;
1117         int error;
1118
1119         fattr = nfs_alloc_fattr();
1120         if (fattr == NULL)
1121                 return -ENOMEM;
1122
1123         /* Sanity: the probe won't work if the destination server
1124          * does not recognize the migrated FH. */
1125         error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
1126
1127         nfs_free_fattr(fattr);
1128         return error;
1129 }
1130
1131 /**
1132  * nfs4_update_server - Move an nfs_server to a different nfs_client
1133  *
1134  * @server: represents FSID to be moved
1135  * @hostname: new end-point's hostname
1136  * @sap: new end-point's socket address
1137  * @salen: size of "sap"
1138  *
1139  * The nfs_server must be quiescent before this function is invoked.
1140  * Either its session is drained (NFSv4.1+), or its transport is
1141  * plugged and drained (NFSv4.0).
1142  *
1143  * Returns zero on success, or a negative errno value.
1144  */
1145 int nfs4_update_server(struct nfs_server *server, const char *hostname,
1146                        struct sockaddr *sap, size_t salen)
1147 {
1148         struct nfs_client *clp = server->nfs_client;
1149         struct rpc_clnt *clnt = server->client;
1150         struct xprt_create xargs = {
1151                 .ident          = clp->cl_proto,
1152                 .net            = &init_net,
1153                 .dstaddr        = sap,
1154                 .addrlen        = salen,
1155                 .servername     = hostname,
1156         };
1157         char buf[INET6_ADDRSTRLEN + 1];
1158         struct sockaddr_storage address;
1159         struct sockaddr *localaddr = (struct sockaddr *)&address;
1160         int error;
1161
1162         dprintk("--> %s: move FSID %llx:%llx to \"%s\")\n", __func__,
1163                         (unsigned long long)server->fsid.major,
1164                         (unsigned long long)server->fsid.minor,
1165                         hostname);
1166
1167         error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1168         if (error != 0) {
1169                 dprintk("<-- %s(): rpc_switch_client_transport returned %d\n",
1170                         __func__, error);
1171                 goto out;
1172         }
1173
1174         error = rpc_localaddr(clnt, localaddr, sizeof(address));
1175         if (error != 0) {
1176                 dprintk("<-- %s(): rpc_localaddr returned %d\n",
1177                         __func__, error);
1178                 goto out;
1179         }
1180
1181         error = -EAFNOSUPPORT;
1182         if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0) {
1183                 dprintk("<-- %s(): rpc_ntop returned %d\n",
1184                         __func__, error);
1185                 goto out;
1186         }
1187
1188         nfs_server_remove_lists(server);
1189         error = nfs4_set_client(server, hostname, sap, salen, buf,
1190                                 clp->cl_rpcclient->cl_auth->au_flavor,
1191                                 clp->cl_proto, clnt->cl_timeout,
1192                                 clp->cl_minorversion, clp->cl_net);
1193         nfs_put_client(clp);
1194         if (error != 0) {
1195                 nfs_server_insert_lists(server);
1196                 dprintk("<-- %s(): nfs4_set_client returned %d\n",
1197                         __func__, error);
1198                 goto out;
1199         }
1200
1201         if (server->nfs_client->cl_hostname == NULL)
1202                 server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1203         nfs_server_insert_lists(server);
1204
1205         error = nfs_probe_destination(server);
1206         if (error < 0)
1207                 goto out;
1208
1209         dprintk("<-- %s() succeeded\n", __func__);
1210
1211 out:
1212         return error;
1213 }