fs/nfs/nfs4client.c

   1 // SPDX-License-Identifier: GPL-2.0-only
   2 /*
   3  * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  */
   6 #include <linux/module.h>
   7 #include <linux/nfs_fs.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 "nfs4idmap.h"
  19 #include "pnfs.h"
  20 #include "netns.h"
  21 #include "sysfs.h"
  22
  23 #define NFSDBG_FACILITY         NFSDBG_CLIENT
  24
  25 /*
  26  * Get a unique NFSv4.0 callback identifier which will be used
  27  * by the V4.0 callback service to lookup the nfs_client struct
  28  */
  29 static int nfs_get_cb_ident_idr(struct nfs_client *clp, int minorversion)
  30 {
  31         int ret = 0;
  32         struct nfs_net *nn = net_generic(clp->cl_net, nfs_net_id);
  33
  34         if (clp->rpc_ops->version != 4 || minorversion != 0)
  35                 return ret;
  36         idr_preload(GFP_KERNEL);
  37         spin_lock(&nn->nfs_client_lock);
  38         ret = idr_alloc(&nn->cb_ident_idr, clp, 1, 0, GFP_NOWAIT);
  39         if (ret >= 0)
  40                 clp->cl_cb_ident = ret;
  41         spin_unlock(&nn->nfs_client_lock);
  42         idr_preload_end();
  43         return ret < 0 ? ret : 0;
  44 }
  45
  46 #ifdef CONFIG_NFS_V4_1
  47 /*
  48  * Per auth flavor data server rpc clients
  49  */
  50 struct nfs4_ds_server {
  51         struct list_head        list;   /* ds_clp->cl_ds_clients */
  52         struct rpc_clnt         *rpc_clnt;
  53 };
  54
  55 /**
  56  * nfs4_find_ds_client - Common lookup case for DS I/O
  57  * @ds_clp: pointer to the DS's nfs_client
  58  * @flavor: rpc auth flavour to match
  59  */
  60 static struct nfs4_ds_server *
  61 nfs4_find_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
  62 {
  63         struct nfs4_ds_server *dss;
  64
  65         rcu_read_lock();
  66         list_for_each_entry_rcu(dss, &ds_clp->cl_ds_clients, list) {
  67                 if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
  68                         continue;
  69                 goto out;
  70         }
  71         dss = NULL;
  72 out:
  73         rcu_read_unlock();
  74         return dss;
  75 }
  76
  77 static struct nfs4_ds_server *
  78 nfs4_add_ds_client(struct nfs_client *ds_clp, rpc_authflavor_t flavor,
  79                            struct nfs4_ds_server *new)
  80 {
  81         struct nfs4_ds_server *dss;
  82
  83         spin_lock(&ds_clp->cl_lock);
  84         list_for_each_entry(dss, &ds_clp->cl_ds_clients, list) {
  85                 if (dss->rpc_clnt->cl_auth->au_flavor != flavor)
  86                         continue;
  87                 goto out;
  88         }
  89         if (new)
  90                 list_add_rcu(&new->list, &ds_clp->cl_ds_clients);
  91         dss = new;
  92 out:
  93         spin_unlock(&ds_clp->cl_lock); /* need some lock to protect list */
  94         return dss;
  95 }
  96
  97 static struct nfs4_ds_server *
  98 nfs4_alloc_ds_server(struct nfs_client *ds_clp, rpc_authflavor_t flavor)
  99 {
 100         struct nfs4_ds_server *dss;
 101
 102         dss = kmalloc(sizeof(*dss), GFP_NOFS);
 103         if (dss == NULL)
 104                 return ERR_PTR(-ENOMEM);
 105
 106         dss->rpc_clnt = rpc_clone_client_set_auth(ds_clp->cl_rpcclient, flavor);
 107         if (IS_ERR(dss->rpc_clnt)) {
 108                 int err = PTR_ERR(dss->rpc_clnt);
 109                 kfree (dss);
 110                 return ERR_PTR(err);
 111         }
 112         INIT_LIST_HEAD(&dss->list);
 113
 114         return dss;
 115 }
 116
 117 static void
 118 nfs4_free_ds_server(struct nfs4_ds_server *dss)
 119 {
 120         rpc_release_client(dss->rpc_clnt);
 121         kfree(dss);
 122 }
 123
 124 /**
 125  * nfs4_find_or_create_ds_client - Find or create a DS rpc client
 126  * @ds_clp: pointer to the DS's nfs_client
 127  * @inode: pointer to the inode
 128  *
 129  * Find or create a DS rpc client with th MDS server rpc client auth flavor
 130  * in the nfs_client cl_ds_clients list.
 131  */
 132 struct rpc_clnt *
 133 nfs4_find_or_create_ds_client(struct nfs_client *ds_clp, struct inode *inode)
 134 {
 135         struct nfs4_ds_server *dss, *new;
 136         rpc_authflavor_t flavor = NFS_SERVER(inode)->client->cl_auth->au_flavor;
 137
 138         dss = nfs4_find_ds_client(ds_clp, flavor);
 139         if (dss != NULL)
 140                 goto out;
 141         new = nfs4_alloc_ds_server(ds_clp, flavor);
 142         if (IS_ERR(new))
 143                 return ERR_CAST(new);
 144         dss = nfs4_add_ds_client(ds_clp, flavor, new);
 145         if (dss != new)
 146                 nfs4_free_ds_server(new);
 147 out:
 148         return dss->rpc_clnt;
 149 }
 150 EXPORT_SYMBOL_GPL(nfs4_find_or_create_ds_client);
 151
 152 static void
 153 nfs4_shutdown_ds_clients(struct nfs_client *clp)
 154 {
 155         struct nfs4_ds_server *dss;
 156
 157         while (!list_empty(&clp->cl_ds_clients)) {
 158                 dss = list_entry(clp->cl_ds_clients.next,
 159                                         struct nfs4_ds_server, list);
 160                 list_del(&dss->list);
 161                 rpc_shutdown_client(dss->rpc_clnt);
 162                 kfree (dss);
 163         }
 164 }
 165
 166 static void
 167 nfs4_cleanup_callback(struct nfs_client *clp)
 168 {
 169         struct nfs4_copy_state *cp_state;
 170
 171         while (!list_empty(&clp->pending_cb_stateids)) {
 172                 cp_state = list_entry(clp->pending_cb_stateids.next,
 173                                         struct nfs4_copy_state, copies);
 174                 list_del(&cp_state->copies);
 175                 kfree(cp_state);
 176         }
 177 }
 178
 179 void nfs41_shutdown_client(struct nfs_client *clp)
 180 {
 181         if (nfs4_has_session(clp)) {
 182                 nfs4_cleanup_callback(clp);
 183                 nfs4_shutdown_ds_clients(clp);
 184                 nfs4_destroy_session(clp->cl_session);
 185                 nfs4_destroy_clientid(clp);
 186         }
 187
 188 }
 189 #endif  /* CONFIG_NFS_V4_1 */
 190
 191 void nfs40_shutdown_client(struct nfs_client *clp)
 192 {
 193         if (clp->cl_slot_tbl) {
 194                 nfs4_shutdown_slot_table(clp->cl_slot_tbl);
 195                 kfree(clp->cl_slot_tbl);
 196         }
 197 }
 198
 199 struct nfs_client *nfs4_alloc_client(const struct nfs_client_initdata *cl_init)
 200 {
 201         char buf[INET6_ADDRSTRLEN + 1];
 202         const char *ip_addr = cl_init->ip_addr;
 203         struct nfs_client *clp = nfs_alloc_client(cl_init);
 204         int err;
 205
 206         if (IS_ERR(clp))
 207                 return clp;
 208
 209         err = nfs_get_cb_ident_idr(clp, cl_init->minorversion);
 210         if (err)
 211                 goto error;
 212
 213         if (cl_init->minorversion > NFS4_MAX_MINOR_VERSION) {
 214                 err = -EINVAL;
 215                 goto error;
 216         }
 217
 218         spin_lock_init(&clp->cl_lock);
 219         INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
 220         INIT_LIST_HEAD(&clp->cl_ds_clients);
 221         rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
 222         clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
 223         clp->cl_mvops = nfs_v4_minor_ops[cl_init->minorversion];
 224         clp->cl_mig_gen = 1;
 225 #if IS_ENABLED(CONFIG_NFS_V4_1)
 226         init_waitqueue_head(&clp->cl_lock_waitq);
 227 #endif
 228         INIT_LIST_HEAD(&clp->pending_cb_stateids);
 229
 230         if (cl_init->minorversion != 0)
 231                 __set_bit(NFS_CS_INFINITE_SLOTS, &clp->cl_flags);
 232         __set_bit(NFS_CS_DISCRTRY, &clp->cl_flags);
 233         __set_bit(NFS_CS_NO_RETRANS_TIMEOUT, &clp->cl_flags);
 234         if (test_bit(NFS_CS_PNFS, &cl_init->init_flags))
 235                 __set_bit(NFS_CS_PNFS, &clp->cl_flags);
 236         /*
 237          * Set up the connection to the server before we add add to the
 238          * global list.
 239          */
 240         err = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_GSS_KRB5I);
 241         if (err == -EINVAL)
 242                 err = nfs_create_rpc_client(clp, cl_init, RPC_AUTH_UNIX);
 243         if (err < 0)
 244                 goto error;
 245
 246         /* If no clientaddr= option was specified, find a usable cb address */
 247         if (ip_addr == NULL) {
 248                 struct sockaddr_storage cb_addr;
 249                 struct sockaddr *sap = (struct sockaddr *)&cb_addr;
 250
 251                 err = rpc_localaddr(clp->cl_rpcclient, sap, sizeof(cb_addr));
 252                 if (err < 0)
 253                         goto error;
 254                 err = rpc_ntop(sap, buf, sizeof(buf));
 255                 if (err < 0)
 256                         goto error;
 257                 ip_addr = (const char *)buf;
 258         }
 259         strscpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
 260
 261         err = nfs_idmap_new(clp);
 262         if (err < 0) {
 263                 dprintk("%s: failed to create idmapper. Error = %d\n",
 264                         __func__, err);
 265                 goto error;
 266         }
 267         __set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
 268         return clp;
 269
 270 error:
 271         nfs_free_client(clp);
 272         return ERR_PTR(err);
 273 }
 274
 275 /*
 276  * Destroy the NFS4 callback service
 277  */
 278 static void nfs4_destroy_callback(struct nfs_client *clp)
 279 {
 280         if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
 281                 nfs_callback_down(clp->cl_mvops->minor_version, clp->cl_net);
 282 }
 283
 284 static void nfs4_shutdown_client(struct nfs_client *clp)
 285 {
 286         if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
 287                 nfs4_kill_renewd(clp);
 288         clp->cl_mvops->shutdown_client(clp);
 289         nfs4_destroy_callback(clp);
 290         if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
 291                 nfs_idmap_delete(clp);
 292
 293         rpc_destroy_wait_queue(&clp->cl_rpcwaitq);
 294         kfree(clp->cl_serverowner);
 295         kfree(clp->cl_serverscope);
 296         kfree(clp->cl_implid);
 297         kfree(clp->cl_owner_id);
 298 }
 299
 300 void nfs4_free_client(struct nfs_client *clp)
 301 {
 302         nfs4_shutdown_client(clp);
 303         nfs_free_client(clp);
 304 }
 305
 306 /*
 307  * Initialize the NFS4 callback service
 308  */
 309 static int nfs4_init_callback(struct nfs_client *clp)
 310 {
 311         struct rpc_xprt *xprt;
 312         int error;
 313
 314         xprt = rcu_dereference_raw(clp->cl_rpcclient->cl_xprt);
 315
 316         if (nfs4_has_session(clp)) {
 317                 error = xprt_setup_backchannel(xprt, NFS41_BC_MIN_CALLBACKS);
 318                 if (error < 0)
 319                         return error;
 320         }
 321
 322         error = nfs_callback_up(clp->cl_mvops->minor_version, xprt);
 323         if (error < 0) {
 324                 dprintk("%s: failed to start callback. Error = %d\n",
 325                         __func__, error);
 326                 return error;
 327         }
 328         __set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
 329
 330         return 0;
 331 }
 332
 333 /**
 334  * nfs40_init_client - nfs_client initialization tasks for NFSv4.0
 335  * @clp: nfs_client to initialize
 336  *
 337  * Returns zero on success, or a negative errno if some error occurred.
 338  */
 339 int nfs40_init_client(struct nfs_client *clp)
 340 {
 341         struct nfs4_slot_table *tbl;
 342         int ret;
 343
 344         tbl = kzalloc(sizeof(*tbl), GFP_NOFS);
 345         if (tbl == NULL)
 346                 return -ENOMEM;
 347
 348         ret = nfs4_setup_slot_table(tbl, NFS4_MAX_SLOT_TABLE,
 349                                         "NFSv4.0 transport Slot table");
 350         if (ret) {
 351                 nfs4_shutdown_slot_table(tbl);
 352                 kfree(tbl);
 353                 return ret;
 354         }
 355
 356         clp->cl_slot_tbl = tbl;
 357         return 0;
 358 }
 359
 360 #if defined(CONFIG_NFS_V4_1)
 361
 362 /**
 363  * nfs41_init_client - nfs_client initialization tasks for NFSv4.1+
 364  * @clp: nfs_client to initialize
 365  *
 366  * Returns zero on success, or a negative errno if some error occurred.
 367  */
 368 int nfs41_init_client(struct nfs_client *clp)
 369 {
 370         struct nfs4_session *session = NULL;
 371
 372         /*
 373          * Create the session and mark it expired.
 374          * When a SEQUENCE operation encounters the expired session
 375          * it will do session recovery to initialize it.
 376          */
 377         session = nfs4_alloc_session(clp);
 378         if (!session)
 379                 return -ENOMEM;
 380
 381         clp->cl_session = session;
 382
 383         /*
 384          * The create session reply races with the server back
 385          * channel probe. Mark the client NFS_CS_SESSION_INITING
 386          * so that the client back channel can find the
 387          * nfs_client struct
 388          */
 389         nfs_mark_client_ready(clp, NFS_CS_SESSION_INITING);
 390         return 0;
 391 }
 392
 393 #endif  /* CONFIG_NFS_V4_1 */
 394
 395 /*
 396  * Initialize the minor version specific parts of an NFS4 client record
 397  */
 398 static int nfs4_init_client_minor_version(struct nfs_client *clp)
 399 {
 400         int ret;
 401
 402         ret = clp->cl_mvops->init_client(clp);
 403         if (ret)
 404                 return ret;
 405         return nfs4_init_callback(clp);
 406 }
 407
 408 static void nfs4_add_trunk(struct nfs_client *clp, struct nfs_client *old)
 409 {
 410         struct sockaddr_storage clp_addr, old_addr;
 411         struct sockaddr *clp_sap = (struct sockaddr *)&clp_addr;
 412         struct sockaddr *old_sap = (struct sockaddr *)&old_addr;
 413         size_t clp_salen;
 414         struct xprt_create xprt_args = {
 415                 .ident = old->cl_proto,
 416                 .net = old->cl_net,
 417                 .servername = old->cl_hostname,
 418         };
 419         int max_connect = test_bit(NFS_CS_PNFS, &clp->cl_flags) ?
 420                 clp->cl_max_connect : old->cl_max_connect;
 421
 422         if (clp->cl_proto != old->cl_proto)
 423                 return;
 424         clp_salen = rpc_peeraddr(clp->cl_rpcclient, clp_sap, sizeof(clp_addr));
 425         rpc_peeraddr(old->cl_rpcclient, old_sap, sizeof(old_addr));
 426
 427         if (clp_addr.ss_family != old_addr.ss_family)
 428                 return;
 429
 430         xprt_args.dstaddr = clp_sap;
 431         xprt_args.addrlen = clp_salen;
 432
 433         rpc_clnt_add_xprt(old->cl_rpcclient, &xprt_args,
 434                           rpc_clnt_test_and_add_xprt, &max_connect);
 435 }
 436
 437 /**
 438  * nfs4_init_client - Initialise an NFS4 client record
 439  *
 440  * @clp: nfs_client to initialise
 441  * @cl_init: pointer to nfs_client_initdata
 442  *
 443  * Returns pointer to an NFS client, or an ERR_PTR value.
 444  */
 445 struct nfs_client *nfs4_init_client(struct nfs_client *clp,
 446                                     const struct nfs_client_initdata *cl_init)
 447 {
 448         struct nfs_client *old;
 449         int error;
 450
 451         if (clp->cl_cons_state == NFS_CS_READY)
 452                 /* the client is initialised already */
 453                 return clp;
 454
 455         error = nfs4_init_client_minor_version(clp);
 456         if (error < 0)
 457                 goto error;
 458
 459         error = nfs4_discover_server_trunking(clp, &old);
 460         if (error < 0)
 461                 goto error;
 462
 463         if (clp != old) {
 464                 clp->cl_preserve_clid = true;
 465                 /*
 466                  * Mark the client as having failed initialization so other
 467                  * processes walking the nfs_client_list in nfs_match_client()
 468                  * won't try to use it.
 469                  */
 470                 nfs_mark_client_ready(clp, -EPERM);
 471                 if (old->cl_mvops->session_trunk)
 472                         nfs4_add_trunk(clp, old);
 473         }
 474         clear_bit(NFS_CS_TSM_POSSIBLE, &clp->cl_flags);
 475         nfs_put_client(clp);
 476         return old;
 477
 478 error:
 479         nfs_mark_client_ready(clp, error);
 480         nfs_put_client(clp);
 481         return ERR_PTR(error);
 482 }
 483
 484 /*
 485  * SETCLIENTID just did a callback update with the callback ident in
 486  * "drop," but server trunking discovery claims "drop" and "keep" are
 487  * actually the same server.  Swap the callback IDs so that "keep"
 488  * will continue to use the callback ident the server now knows about,
 489  * and so that "keep"'s original callback ident is destroyed when
 490  * "drop" is freed.
 491  */
 492 static void nfs4_swap_callback_idents(struct nfs_client *keep,
 493                                       struct nfs_client *drop)
 494 {
 495         struct nfs_net *nn = net_generic(keep->cl_net, nfs_net_id);
 496         unsigned int save = keep->cl_cb_ident;
 497
 498         if (keep->cl_cb_ident == drop->cl_cb_ident)
 499                 return;
 500
 501         dprintk("%s: keeping callback ident %u and dropping ident %u\n",
 502                 __func__, keep->cl_cb_ident, drop->cl_cb_ident);
 503
 504         spin_lock(&nn->nfs_client_lock);
 505
 506         idr_replace(&nn->cb_ident_idr, keep, drop->cl_cb_ident);
 507         keep->cl_cb_ident = drop->cl_cb_ident;
 508
 509         idr_replace(&nn->cb_ident_idr, drop, save);
 510         drop->cl_cb_ident = save;
 511
 512         spin_unlock(&nn->nfs_client_lock);
 513 }
 514
 515 static bool nfs4_match_client_owner_id(const struct nfs_client *clp1,
 516                 const struct nfs_client *clp2)
 517 {
 518         if (clp1->cl_owner_id == NULL || clp2->cl_owner_id == NULL)
 519                 return true;
 520         return strcmp(clp1->cl_owner_id, clp2->cl_owner_id) == 0;
 521 }
 522
 523 static bool nfs4_same_verifier(nfs4_verifier *v1, nfs4_verifier *v2)
 524 {
 525         return memcmp(v1->data, v2->data, sizeof(v1->data)) == 0;
 526 }
 527
 528 static int nfs4_match_client(struct nfs_client  *pos,  struct nfs_client *new,
 529                              struct nfs_client **prev, struct nfs_net *nn)
 530 {
 531         int status;
 532
 533         if (pos->rpc_ops != new->rpc_ops)
 534                 return 1;
 535
 536         if (pos->cl_minorversion != new->cl_minorversion)
 537                 return 1;
 538
 539         /* If "pos" isn't marked ready, we can't trust the
 540          * remaining fields in "pos", especially the client
 541          * ID and serverowner fields.  Wait for CREATE_SESSION
 542          * to finish. */
 543         if (pos->cl_cons_state > NFS_CS_READY) {
 544                 refcount_inc(&pos->cl_count);
 545                 spin_unlock(&nn->nfs_client_lock);
 546
 547                 nfs_put_client(*prev);
 548                 *prev = pos;
 549
 550                 status = nfs_wait_client_init_complete(pos);
 551                 spin_lock(&nn->nfs_client_lock);
 552
 553                 if (status < 0)
 554                         return status;
 555         }
 556
 557         if (pos->cl_cons_state != NFS_CS_READY)
 558                 return 1;
 559
 560         if (pos->cl_clientid != new->cl_clientid)
 561                 return 1;
 562
 563         /* NFSv4.1 always uses the uniform string, however someone
 564          * might switch the uniquifier string on us.
 565          */
 566         if (!nfs4_match_client_owner_id(pos, new))
 567                 return 1;
 568
 569         return 0;
 570 }
 571
 572 /**
 573  * nfs40_walk_client_list - Find server that recognizes a client ID
 574  *
 575  * @new: nfs_client with client ID to test
 576  * @result: OUT: found nfs_client, or new
 577  * @cred: credential to use for trunking test
 578  *
 579  * Returns zero, a negative errno, or a negative NFS4ERR status.
 580  * If zero is returned, an nfs_client pointer is planted in "result."
 581  *
 582  * NB: nfs40_walk_client_list() relies on the new nfs_client being
 583  *     the last nfs_client on the list.
 584  */
 585 int nfs40_walk_client_list(struct nfs_client *new,
 586                            struct nfs_client **result,
 587                            const struct cred *cred)
 588 {
 589         struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 590         struct nfs_client *pos, *prev = NULL;
 591         struct nfs4_setclientid_res clid = {
 592                 .clientid       = new->cl_clientid,
 593                 .confirm        = new->cl_confirm,
 594         };
 595         int status = -NFS4ERR_STALE_CLIENTID;
 596
 597         spin_lock(&nn->nfs_client_lock);
 598         list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 599
 600                 if (pos == new)
 601                         goto found;
 602
 603                 status = nfs4_match_client(pos, new, &prev, nn);
 604                 if (status < 0)
 605                         goto out_unlock;
 606                 if (status != 0)
 607                         continue;
 608                 /*
 609                  * We just sent a new SETCLIENTID, which should have
 610                  * caused the server to return a new cl_confirm.  So if
 611                  * cl_confirm is the same, then this is a different
 612                  * server that just returned the same cl_confirm by
 613                  * coincidence:
 614                  */
 615                 if ((new != pos) && nfs4_same_verifier(&pos->cl_confirm,
 616                                                        &new->cl_confirm))
 617                         continue;
 618                 /*
 619                  * But if the cl_confirm's are different, then the only
 620                  * way that a SETCLIENTID_CONFIRM to pos can succeed is
 621                  * if new and pos point to the same server:
 622                  */
 623 found:
 624                 refcount_inc(&pos->cl_count);
 625                 spin_unlock(&nn->nfs_client_lock);
 626
 627                 nfs_put_client(prev);
 628                 prev = pos;
 629
 630                 status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
 631                 switch (status) {
 632                 case -NFS4ERR_STALE_CLIENTID:
 633                         break;
 634                 case 0:
 635                         nfs4_swap_callback_idents(pos, new);
 636                         pos->cl_confirm = new->cl_confirm;
 637                         nfs_mark_client_ready(pos, NFS_CS_READY);
 638
 639                         prev = NULL;
 640                         *result = pos;
 641                         goto out;
 642                 case -ERESTARTSYS:
 643                 case -ETIMEDOUT:
 644                         /* The callback path may have been inadvertently
 645                          * changed. Schedule recovery!
 646                          */
 647                         nfs4_schedule_path_down_recovery(pos);
 648                         goto out;
 649                 default:
 650                         goto out;
 651                 }
 652
 653                 spin_lock(&nn->nfs_client_lock);
 654         }
 655 out_unlock:
 656         spin_unlock(&nn->nfs_client_lock);
 657
 658         /* No match found. The server lost our clientid */
 659 out:
 660         nfs_put_client(prev);
 661         return status;
 662 }
 663
 664 #ifdef CONFIG_NFS_V4_1
 665 /*
 666  * Returns true if the server major ids match
 667  */
 668 bool
 669 nfs4_check_serverowner_major_id(struct nfs41_server_owner *o1,
 670                                 struct nfs41_server_owner *o2)
 671 {
 672         if (o1->major_id_sz != o2->major_id_sz)
 673                 return false;
 674         return memcmp(o1->major_id, o2->major_id, o1->major_id_sz) == 0;
 675 }
 676
 677 /*
 678  * Returns true if the server scopes match
 679  */
 680 static bool
 681 nfs4_check_server_scope(struct nfs41_server_scope *s1,
 682                         struct nfs41_server_scope *s2)
 683 {
 684         if (s1->server_scope_sz != s2->server_scope_sz)
 685                 return false;
 686         return memcmp(s1->server_scope, s2->server_scope,
 687                                         s1->server_scope_sz) == 0;
 688 }
 689
 690 /**
 691  * nfs4_detect_session_trunking - Checks for session trunking.
 692  * @clp:    original mount nfs_client
 693  * @res:    result structure from an exchange_id using the original mount
 694  *          nfs_client with a new multi_addr transport
 695  * @xprt:   pointer to the transport to add.
 696  *
 697  * Called after a successful EXCHANGE_ID on a multi-addr connection.
 698  * Upon success, add the transport.
 699  *
 700  * Returns zero on success, otherwise -EINVAL
 701  *
 702  * Note: since the exchange_id for the new multi_addr transport uses the
 703  * same nfs_client from the original mount, the cl_owner_id is reused,
 704  * so eir_clientowner is the same.
 705  */
 706 int nfs4_detect_session_trunking(struct nfs_client *clp,
 707                                  struct nfs41_exchange_id_res *res,
 708                                  struct rpc_xprt *xprt)
 709 {
 710         /* Check eir_clientid */
 711         if (clp->cl_clientid != res->clientid)
 712                 goto out_err;
 713
 714         /* Check eir_server_owner so_major_id */
 715         if (!nfs4_check_serverowner_major_id(clp->cl_serverowner,
 716                                              res->server_owner))
 717                 goto out_err;
 718
 719         /* Check eir_server_owner so_minor_id */
 720         if (clp->cl_serverowner->minor_id != res->server_owner->minor_id)
 721                 goto out_err;
 722
 723         /* Check eir_server_scope */
 724         if (!nfs4_check_server_scope(clp->cl_serverscope, res->server_scope))
 725                 goto out_err;
 726
 727         pr_info("NFS:  %s: Session trunking succeeded for %s\n",
 728                 clp->cl_hostname,
 729                 xprt->address_strings[RPC_DISPLAY_ADDR]);
 730
 731         return 0;
 732 out_err:
 733         pr_info("NFS:  %s: Session trunking failed for %s\n", clp->cl_hostname,
 734                 xprt->address_strings[RPC_DISPLAY_ADDR]);
 735
 736         return -EINVAL;
 737 }
 738
 739 /**
 740  * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
 741  *
 742  * @new: nfs_client with client ID to test
 743  * @result: OUT: found nfs_client, or new
 744  * @cred: credential to use for trunking test
 745  *
 746  * Returns zero, a negative errno, or a negative NFS4ERR status.
 747  * If zero is returned, an nfs_client pointer is planted in "result."
 748  *
 749  * NB: nfs41_walk_client_list() relies on the new nfs_client being
 750  *     the last nfs_client on the list.
 751  */
 752 int nfs41_walk_client_list(struct nfs_client *new,
 753                            struct nfs_client **result,
 754                            const struct cred *cred)
 755 {
 756         struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 757         struct nfs_client *pos, *prev = NULL;
 758         int status = -NFS4ERR_STALE_CLIENTID;
 759
 760         spin_lock(&nn->nfs_client_lock);
 761         list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 762
 763                 if (pos == new)
 764                         goto found;
 765
 766                 status = nfs4_match_client(pos, new, &prev, nn);
 767                 if (status < 0)
 768                         goto out;
 769                 if (status != 0)
 770                         continue;
 771
 772                 /*
 773                  * Note that session trunking is just a special subcase of
 774                  * client id trunking. In either case, we want to fall back
 775                  * to using the existing nfs_client.
 776                  */
 777                 if (!nfs4_check_serverowner_major_id(pos->cl_serverowner,
 778                                                      new->cl_serverowner))
 779                         continue;
 780
 781 found:
 782                 refcount_inc(&pos->cl_count);
 783                 *result = pos;
 784                 status = 0;
 785                 break;
 786         }
 787
 788 out:
 789         spin_unlock(&nn->nfs_client_lock);
 790         nfs_put_client(prev);
 791         return status;
 792 }
 793 #endif  /* CONFIG_NFS_V4_1 */
 794
 795 static void nfs4_destroy_server(struct nfs_server *server)
 796 {
 797         LIST_HEAD(freeme);
 798
 799         nfs_server_return_all_delegations(server);
 800         unset_pnfs_layoutdriver(server);
 801         nfs4_purge_state_owners(server, &freeme);
 802         nfs4_free_state_owners(&freeme);
 803 }
 804
 805 /*
 806  * NFSv4.0 callback thread helper
 807  *
 808  * Find a client by callback identifier
 809  */
 810 struct nfs_client *
 811 nfs4_find_client_ident(struct net *net, int cb_ident)
 812 {
 813         struct nfs_client *clp;
 814         struct nfs_net *nn = net_generic(net, nfs_net_id);
 815
 816         spin_lock(&nn->nfs_client_lock);
 817         clp = idr_find(&nn->cb_ident_idr, cb_ident);
 818         if (clp)
 819                 refcount_inc(&clp->cl_count);
 820         spin_unlock(&nn->nfs_client_lock);
 821         return clp;
 822 }
 823
 824 #if defined(CONFIG_NFS_V4_1)
 825 /* Common match routine for v4.0 and v4.1 callback services */
 826 static bool nfs4_cb_match_client(const struct sockaddr *addr,
 827                 struct nfs_client *clp, u32 minorversion)
 828 {
 829         struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 830
 831         /* Don't match clients that failed to initialise */
 832         if (!(clp->cl_cons_state == NFS_CS_READY ||
 833             clp->cl_cons_state == NFS_CS_SESSION_INITING))
 834                 return false;
 835
 836         smp_rmb();
 837
 838         /* Match the version and minorversion */
 839         if (clp->rpc_ops->version != 4 ||
 840             clp->cl_minorversion != minorversion)
 841                 return false;
 842
 843         /* Match only the IP address, not the port number */
 844         return rpc_cmp_addr(addr, clap);
 845 }
 846
 847 /*
 848  * NFSv4.1 callback thread helper
 849  * For CB_COMPOUND calls, find a client by IP address, protocol version,
 850  * minorversion, and sessionID
 851  *
 852  * Returns NULL if no such client
 853  */
 854 struct nfs_client *
 855 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 856                            struct nfs4_sessionid *sid, u32 minorversion)
 857 {
 858         struct nfs_client *clp;
 859         struct nfs_net *nn = net_generic(net, nfs_net_id);
 860
 861         spin_lock(&nn->nfs_client_lock);
 862         list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 863                 if (!nfs4_cb_match_client(addr, clp, minorversion))
 864                         continue;
 865
 866                 if (!nfs4_has_session(clp))
 867                         continue;
 868
 869                 /* Match sessionid*/
 870                 if (memcmp(clp->cl_session->sess_id.data,
 871                     sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
 872                         continue;
 873
 874                 refcount_inc(&clp->cl_count);
 875                 spin_unlock(&nn->nfs_client_lock);
 876                 return clp;
 877         }
 878         spin_unlock(&nn->nfs_client_lock);
 879         return NULL;
 880 }
 881
 882 #else /* CONFIG_NFS_V4_1 */
 883
 884 struct nfs_client *
 885 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 886                            struct nfs4_sessionid *sid, u32 minorversion)
 887 {
 888         return NULL;
 889 }
 890 #endif /* CONFIG_NFS_V4_1 */
 891
 892 /*
 893  * Set up an NFS4 client
 894  */
 895 static int nfs4_set_client(struct nfs_server *server,
 896                 const char *hostname,
 897                 const struct sockaddr_storage *addr,
 898                 const size_t addrlen,
 899                 const char *ip_addr,
 900                 int proto, const struct rpc_timeout *timeparms,
 901                 u32 minorversion, unsigned int nconnect,
 902                 unsigned int max_connect,
 903                 struct net *net,
 904                 struct xprtsec_parms *xprtsec)
 905 {
 906         struct nfs_client_initdata cl_init = {
 907                 .hostname = hostname,
 908                 .addr = addr,
 909                 .addrlen = addrlen,
 910                 .ip_addr = ip_addr,
 911                 .nfs_mod = &nfs_v4,
 912                 .proto = proto,
 913                 .minorversion = minorversion,
 914                 .net = net,
 915                 .timeparms = timeparms,
 916                 .cred = server->cred,
 917                 .xprtsec = *xprtsec,
 918         };
 919         struct nfs_client *clp;
 920
 921         if (minorversion == 0)
 922                 __set_bit(NFS_CS_REUSEPORT, &cl_init.init_flags);
 923         else
 924                 cl_init.max_connect = max_connect;
 925         switch (proto) {
 926         case XPRT_TRANSPORT_RDMA:
 927         case XPRT_TRANSPORT_TCP:
 928         case XPRT_TRANSPORT_TCP_TLS:
 929                 cl_init.nconnect = nconnect;
 930         }
 931
 932         if (server->flags & NFS_MOUNT_NORESVPORT)
 933                 __set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 934         if (server->options & NFS_OPTION_MIGRATION)
 935                 __set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
 936         if (test_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status))
 937                 __set_bit(NFS_CS_TSM_POSSIBLE, &cl_init.init_flags);
 938         server->port = rpc_get_port((struct sockaddr *)addr);
 939
 940         /* Allocate or find a client reference we can use */
 941         clp = nfs_get_client(&cl_init);
 942         if (IS_ERR(clp))
 943                 return PTR_ERR(clp);
 944
 945         if (server->nfs_client == clp) {
 946                 nfs_put_client(clp);
 947                 return -ELOOP;
 948         }
 949
 950         /*
 951          * Query for the lease time on clientid setup or renewal
 952          *
 953          * Note that this will be set on nfs_clients that were created
 954          * only for the DS role and did not set this bit, but now will
 955          * serve a dual role.
 956          */
 957         set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
 958
 959         server->nfs_client = clp;
 960         nfs_sysfs_add_server(server);
 961         nfs_sysfs_link_rpc_client(server, clp->cl_rpcclient, "_state");
 962
 963         return 0;
 964 }
 965
 966 /*
 967  * Set up a pNFS Data Server client.
 968  *
 969  * Return any existing nfs_client that matches server address,port,version
 970  * and minorversion.
 971  *
 972  * For a new nfs_client, use a soft mount (default), a low retrans and a
 973  * low timeout interval so that if a connection is lost, we retry through
 974  * the MDS.
 975  */
 976 struct nfs_client *nfs4_set_ds_client(struct nfs_server *mds_srv,
 977                 const struct sockaddr_storage *ds_addr, int ds_addrlen,
 978                 int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans,
 979                 u32 minor_version)
 980 {
 981         struct rpc_timeout ds_timeout;
 982         struct nfs_client *mds_clp = mds_srv->nfs_client;
 983         struct nfs_client_initdata cl_init = {
 984                 .addr = ds_addr,
 985                 .addrlen = ds_addrlen,
 986                 .nodename = mds_clp->cl_rpcclient->cl_nodename,
 987                 .ip_addr = mds_clp->cl_ipaddr,
 988                 .nfs_mod = &nfs_v4,
 989                 .proto = ds_proto,
 990                 .minorversion = minor_version,
 991                 .net = mds_clp->cl_net,
 992                 .timeparms = &ds_timeout,
 993                 .cred = mds_srv->cred,
 994                 .xprtsec = mds_srv->nfs_client->cl_xprtsec,
 995         };
 996         char buf[INET6_ADDRSTRLEN + 1];
 997
 998         if (rpc_ntop((struct sockaddr *)ds_addr, buf, sizeof(buf)) <= 0)
 999                 return ERR_PTR(-EINVAL);
1000         cl_init.hostname = buf;
1001
1002         switch (ds_proto) {
1003         case XPRT_TRANSPORT_RDMA:
1004         case XPRT_TRANSPORT_TCP:
1005         case XPRT_TRANSPORT_TCP_TLS:
1006                 if (mds_clp->cl_nconnect > 1) {
1007                         cl_init.nconnect = mds_clp->cl_nconnect;
1008                         cl_init.max_connect = NFS_MAX_TRANSPORTS;
1009                 }
1010         }
1011
1012         if (mds_srv->flags & NFS_MOUNT_NORESVPORT)
1013                 __set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
1014
1015         __set_bit(NFS_CS_PNFS, &cl_init.init_flags);
1016         cl_init.max_connect = NFS_MAX_TRANSPORTS;
1017         /*
1018          * Set an authflavor equual to the MDS value. Use the MDS nfs_client
1019          * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
1020          * (section 13.1 RFC 5661).
1021          */
1022         nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
1023         return nfs_get_client(&cl_init);
1024 }
1025 EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
1026
1027 /*
1028  * Session has been established, and the client marked ready.
1029  * Limit the mount rsize, wsize and dtsize using negotiated fore
1030  * channel attributes.
1031  */
1032 static void nfs4_session_limit_rwsize(struct nfs_server *server)
1033 {
1034 #ifdef CONFIG_NFS_V4_1
1035         struct nfs4_session *sess;
1036         u32 server_resp_sz;
1037         u32 server_rqst_sz;
1038
1039         if (!nfs4_has_session(server->nfs_client))
1040                 return;
1041         sess = server->nfs_client->cl_session;
1042         server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
1043         server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
1044
1045         if (server->dtsize > server_resp_sz)
1046                 server->dtsize = server_resp_sz;
1047         if (server->rsize > server_resp_sz)
1048                 server->rsize = server_resp_sz;
1049         if (server->wsize > server_rqst_sz)
1050                 server->wsize = server_rqst_sz;
1051 #endif /* CONFIG_NFS_V4_1 */
1052 }
1053
1054 /*
1055  * Limit xattr sizes using the channel attributes.
1056  */
1057 static void nfs4_session_limit_xasize(struct nfs_server *server)
1058 {
1059 #ifdef CONFIG_NFS_V4_2
1060         struct nfs4_session *sess;
1061         u32 server_gxa_sz;
1062         u32 server_sxa_sz;
1063         u32 server_lxa_sz;
1064
1065         if (!nfs4_has_session(server->nfs_client))
1066                 return;
1067
1068         sess = server->nfs_client->cl_session;
1069
1070         server_gxa_sz = sess->fc_attrs.max_resp_sz - nfs42_maxgetxattr_overhead;
1071         server_sxa_sz = sess->fc_attrs.max_rqst_sz - nfs42_maxsetxattr_overhead;
1072         server_lxa_sz = sess->fc_attrs.max_resp_sz -
1073             nfs42_maxlistxattrs_overhead;
1074
1075         if (server->gxasize > server_gxa_sz)
1076                 server->gxasize = server_gxa_sz;
1077         if (server->sxasize > server_sxa_sz)
1078                 server->sxasize = server_sxa_sz;
1079         if (server->lxasize > server_lxa_sz)
1080                 server->lxasize = server_lxa_sz;
1081 #endif
1082 }
1083
1084 void nfs4_server_set_init_caps(struct nfs_server *server)
1085 {
1086         /* Set the basic capabilities */
1087         server->caps |= server->nfs_client->cl_mvops->init_caps;
1088         if (server->flags & NFS_MOUNT_NORDIRPLUS)
1089                         server->caps &= ~NFS_CAP_READDIRPLUS;
1090         if (server->nfs_client->cl_proto == XPRT_TRANSPORT_RDMA)
1091                 server->caps &= ~NFS_CAP_READ_PLUS;
1092
1093         /*
1094          * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
1095          * authentication.
1096          */
1097         if (nfs4_disable_idmapping &&
1098                         server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
1099                 server->caps |= NFS_CAP_UIDGID_NOMAP;
1100 }
1101
1102 static int nfs4_server_common_setup(struct nfs_server *server,
1103                 struct nfs_fh *mntfh, bool auth_probe)
1104 {
1105         int error;
1106
1107         /* data servers support only a subset of NFSv4.1 */
1108         if (is_ds_only_client(server->nfs_client))
1109                 return -EPROTONOSUPPORT;
1110
1111         /* We must ensure the session is initialised first */
1112         error = nfs4_init_session(server->nfs_client);
1113         if (error < 0)
1114                 goto out;
1115
1116         nfs4_server_set_init_caps(server);
1117
1118         /* Probe the root fh to retrieve its FSID and filehandle */
1119         error = nfs4_get_rootfh(server, mntfh, auth_probe);
1120         if (error < 0)
1121                 goto out;
1122
1123         dprintk("Server FSID: %llx:%llx\n",
1124                         (unsigned long long) server->fsid.major,
1125                         (unsigned long long) server->fsid.minor);
1126         nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
1127
1128         error = nfs_probe_server(server, mntfh);
1129         if (error < 0)
1130                 goto out;
1131
1132         nfs4_session_limit_rwsize(server);
1133         nfs4_session_limit_xasize(server);
1134
1135         if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1136                 server->namelen = NFS4_MAXNAMLEN;
1137
1138         nfs_server_insert_lists(server);
1139         server->mount_time = jiffies;
1140         server->destroy = nfs4_destroy_server;
1141 out:
1142         return error;
1143 }
1144
1145 /*
1146  * Create a version 4 volume record
1147  */
1148 static int nfs4_init_server(struct nfs_server *server, struct fs_context *fc)
1149 {
1150         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1151         struct rpc_timeout timeparms;
1152         int error;
1153
1154         nfs_init_timeout_values(&timeparms, ctx->nfs_server.protocol,
1155                                 ctx->timeo, ctx->retrans);
1156
1157         /* Initialise the client representation from the mount data */
1158         server->flags = ctx->flags;
1159         server->options = ctx->options;
1160         server->auth_info = ctx->auth_info;
1161
1162         /* Use the first specified auth flavor. If this flavor isn't
1163          * allowed by the server, use the SECINFO path to try the
1164          * other specified flavors */
1165         if (ctx->auth_info.flavor_len >= 1)
1166                 ctx->selected_flavor = ctx->auth_info.flavors[0];
1167         else
1168                 ctx->selected_flavor = RPC_AUTH_UNIX;
1169
1170         /* Get a client record */
1171         error = nfs4_set_client(server,
1172                                 ctx->nfs_server.hostname,
1173                                 &ctx->nfs_server._address,
1174                                 ctx->nfs_server.addrlen,
1175                                 ctx->client_address,
1176                                 ctx->nfs_server.protocol,
1177                                 &timeparms,
1178                                 ctx->minorversion,
1179                                 ctx->nfs_server.nconnect,
1180                                 ctx->nfs_server.max_connect,
1181                                 fc->net_ns,
1182                                 &ctx->xprtsec);
1183         if (error < 0)
1184                 return error;
1185
1186         if (ctx->rsize)
1187                 server->rsize = nfs_io_size(ctx->rsize, server->nfs_client->cl_proto);
1188         if (ctx->wsize)
1189                 server->wsize = nfs_io_size(ctx->wsize, server->nfs_client->cl_proto);
1190
1191         server->acregmin = ctx->acregmin * HZ;
1192         server->acregmax = ctx->acregmax * HZ;
1193         server->acdirmin = ctx->acdirmin * HZ;
1194         server->acdirmax = ctx->acdirmax * HZ;
1195         server->port     = ctx->nfs_server.port;
1196
1197         return nfs_init_server_rpcclient(server, &timeparms,
1198                                          ctx->selected_flavor);
1199 }
1200
1201 /*
1202  * Create a version 4 volume record
1203  * - keyed on server and FSID
1204  */
1205 struct nfs_server *nfs4_create_server(struct fs_context *fc)
1206 {
1207         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1208         struct nfs_server *server;
1209         bool auth_probe;
1210         int error;
1211
1212         server = nfs_alloc_server();
1213         if (!server)
1214                 return ERR_PTR(-ENOMEM);
1215
1216         server->cred = get_cred(fc->cred);
1217
1218         auth_probe = ctx->auth_info.flavor_len < 1;
1219
1220         /* set up the general RPC client */
1221         error = nfs4_init_server(server, fc);
1222         if (error < 0)
1223                 goto error;
1224
1225         error = nfs4_server_common_setup(server, ctx->mntfh, auth_probe);
1226         if (error < 0)
1227                 goto error;
1228
1229         return server;
1230
1231 error:
1232         nfs_free_server(server);
1233         return ERR_PTR(error);
1234 }
1235
1236 /*
1237  * Create an NFS4 referral server record
1238  */
1239 struct nfs_server *nfs4_create_referral_server(struct fs_context *fc)
1240 {
1241         struct nfs_fs_context *ctx = nfs_fc2context(fc);
1242         struct nfs_client *parent_client;
1243         struct nfs_server *server, *parent_server;
1244         int proto, error;
1245         bool auth_probe;
1246
1247         server = nfs_alloc_server();
1248         if (!server)
1249                 return ERR_PTR(-ENOMEM);
1250
1251         parent_server = NFS_SB(ctx->clone_data.sb);
1252         parent_client = parent_server->nfs_client;
1253
1254         server->cred = get_cred(parent_server->cred);
1255
1256         /* Initialise the client representation from the parent server */
1257         nfs_server_copy_userdata(server, parent_server);
1258
1259         /* Get a client representation */
1260 #if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
1261         rpc_set_port(&ctx->nfs_server.address, NFS_RDMA_PORT);
1262         error = nfs4_set_client(server,
1263                                 ctx->nfs_server.hostname,
1264                                 &ctx->nfs_server._address,
1265                                 ctx->nfs_server.addrlen,
1266                                 parent_client->cl_ipaddr,
1267                                 XPRT_TRANSPORT_RDMA,
1268                                 parent_server->client->cl_timeout,
1269                                 parent_client->cl_mvops->minor_version,
1270                                 parent_client->cl_nconnect,
1271                                 parent_client->cl_max_connect,
1272                                 parent_client->cl_net,
1273                                 &parent_client->cl_xprtsec);
1274         if (!error)
1275                 goto init_server;
1276 #endif  /* IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA) */
1277
1278         proto = XPRT_TRANSPORT_TCP;
1279         if (parent_client->cl_xprtsec.policy != RPC_XPRTSEC_NONE)
1280                 proto = XPRT_TRANSPORT_TCP_TLS;
1281         rpc_set_port(&ctx->nfs_server.address, NFS_PORT);
1282         error = nfs4_set_client(server,
1283                                 ctx->nfs_server.hostname,
1284                                 &ctx->nfs_server._address,
1285                                 ctx->nfs_server.addrlen,
1286                                 parent_client->cl_ipaddr,
1287                                 proto,
1288                                 parent_server->client->cl_timeout,
1289                                 parent_client->cl_mvops->minor_version,
1290                                 parent_client->cl_nconnect,
1291                                 parent_client->cl_max_connect,
1292                                 parent_client->cl_net,
1293                                 &parent_client->cl_xprtsec);
1294         if (error < 0)
1295                 goto error;
1296
1297 #if IS_ENABLED(CONFIG_SUNRPC_XPRT_RDMA)
1298 init_server:
1299 #endif
1300         error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout,
1301                                           ctx->selected_flavor);
1302         if (error < 0)
1303                 goto error;
1304
1305         auth_probe = parent_server->auth_info.flavor_len < 1;
1306
1307         error = nfs4_server_common_setup(server, ctx->mntfh, auth_probe);
1308         if (error < 0)
1309                 goto error;
1310
1311         return server;
1312
1313 error:
1314         nfs_free_server(server);
1315         return ERR_PTR(error);
1316 }
1317
1318 /**
1319  * nfs4_update_server - Move an nfs_server to a different nfs_client
1320  *
1321  * @server: represents FSID to be moved
1322  * @hostname: new end-point's hostname
1323  * @sap: new end-point's socket address
1324  * @salen: size of "sap"
1325  * @net: net namespace
1326  *
1327  * The nfs_server must be quiescent before this function is invoked.
1328  * Either its session is drained (NFSv4.1+), or its transport is
1329  * plugged and drained (NFSv4.0).
1330  *
1331  * Returns zero on success, or a negative errno value.
1332  */
1333 int nfs4_update_server(struct nfs_server *server, const char *hostname,
1334                        struct sockaddr_storage *sap, size_t salen, struct net *net)
1335 {
1336         struct nfs_client *clp = server->nfs_client;
1337         struct rpc_clnt *clnt = server->client;
1338         struct xprt_create xargs = {
1339                 .ident          = clp->cl_proto,
1340                 .net            = net,
1341                 .dstaddr        = (struct sockaddr *)sap,
1342                 .addrlen        = salen,
1343                 .servername     = hostname,
1344                 /* cel: bleh. We might need to pass TLS parameters here */
1345         };
1346         char buf[INET6_ADDRSTRLEN + 1];
1347         struct sockaddr_storage address;
1348         struct sockaddr *localaddr = (struct sockaddr *)&address;
1349         int error;
1350
1351         error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1352         if (error != 0)
1353                 return error;
1354
1355         error = rpc_localaddr(clnt, localaddr, sizeof(address));
1356         if (error != 0)
1357                 return error;
1358
1359         if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0)
1360                 return -EAFNOSUPPORT;
1361
1362         nfs_server_remove_lists(server);
1363         set_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1364         error = nfs4_set_client(server, hostname, sap, salen, buf,
1365                                 clp->cl_proto, clnt->cl_timeout,
1366                                 clp->cl_minorversion,
1367                                 clp->cl_nconnect, clp->cl_max_connect,
1368                                 net, &clp->cl_xprtsec);
1369         clear_bit(NFS_MIG_TSM_POSSIBLE, &server->mig_status);
1370         if (error != 0) {
1371                 nfs_server_insert_lists(server);
1372                 return error;
1373         }
1374         nfs_put_client(clp);
1375
1376         if (server->nfs_client->cl_hostname == NULL) {
1377                 server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1378                 if (server->nfs_client->cl_hostname == NULL)
1379                         return -ENOMEM;
1380         }
1381         nfs_server_insert_lists(server);
1382
1383         return nfs_probe_server(server, NFS_FH(d_inode(server->super->s_root)));
1384 }