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, 1, 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
 486                 if (pos->rpc_ops != new->rpc_ops)
 487                         continue;
 488
 489                 if (pos->cl_proto != new->cl_proto)
 490                         continue;
 491
 492                 if (pos->cl_minorversion != new->cl_minorversion)
 493                         continue;
 494
 495                 /* If "pos" isn't marked ready, we can't trust the
 496                  * remaining fields in "pos" */
 497                 if (pos->cl_cons_state > NFS_CS_READY) {
 498                         atomic_inc(&pos->cl_count);
 499                         spin_unlock(&nn->nfs_client_lock);
 500
 501                         if (prev)
 502                                 nfs_put_client(prev);
 503                         prev = pos;
 504
 505                         status = nfs_wait_client_init_complete(pos);
 506                         if (status < 0)
 507                                 goto out;
 508                         status = -NFS4ERR_STALE_CLIENTID;
 509                         spin_lock(&nn->nfs_client_lock);
 510                 }
 511                 if (pos->cl_cons_state != NFS_CS_READY)
 512                         continue;
 513
 514                 if (pos->cl_clientid != new->cl_clientid)
 515                         continue;
 516
 517                 atomic_inc(&pos->cl_count);
 518                 spin_unlock(&nn->nfs_client_lock);
 519
 520                 if (prev)
 521                         nfs_put_client(prev);
 522                 prev = pos;
 523
 524                 status = nfs4_proc_setclientid_confirm(pos, &clid, cred);
 525                 switch (status) {
 526                 case -NFS4ERR_STALE_CLIENTID:
 527                         break;
 528                 case 0:
 529                         nfs4_swap_callback_idents(pos, new);
 530
 531                         prev = NULL;
 532                         *result = pos;
 533                         dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
 534                                 __func__, pos, atomic_read(&pos->cl_count));
 535                         goto out;
 536                 case -ERESTARTSYS:
 537                 case -ETIMEDOUT:
 538                         /* The callback path may have been inadvertently
 539                          * changed. Schedule recovery!
 540                          */
 541                         nfs4_schedule_path_down_recovery(pos);
 542                 default:
 543                         goto out;
 544                 }
 545
 546                 spin_lock(&nn->nfs_client_lock);
 547         }
 548         spin_unlock(&nn->nfs_client_lock);
 549
 550         /* No match found. The server lost our clientid */
 551 out:
 552         if (prev)
 553                 nfs_put_client(prev);
 554         dprintk("NFS: <-- %s status = %d\n", __func__, status);
 555         return status;
 556 }
 557
 558 #ifdef CONFIG_NFS_V4_1
 559 /*
 560  * Returns true if the client IDs match
 561  */
 562 static bool nfs4_match_clientids(struct nfs_client *a, struct nfs_client *b)
 563 {
 564         if (a->cl_clientid != b->cl_clientid) {
 565                 dprintk("NFS: --> %s client ID %llx does not match %llx\n",
 566                         __func__, a->cl_clientid, b->cl_clientid);
 567                 return false;
 568         }
 569         dprintk("NFS: --> %s client ID %llx matches %llx\n",
 570                 __func__, a->cl_clientid, b->cl_clientid);
 571         return true;
 572 }
 573
 574 /*
 575  * Returns true if the server major ids match
 576  */
 577 static bool
 578 nfs4_check_clientid_trunking(struct nfs_client *a, struct nfs_client *b)
 579 {
 580         struct nfs41_server_owner *o1 = a->cl_serverowner;
 581         struct nfs41_server_owner *o2 = b->cl_serverowner;
 582
 583         if (o1->major_id_sz != o2->major_id_sz)
 584                 goto out_major_mismatch;
 585         if (memcmp(o1->major_id, o2->major_id, o1->major_id_sz) != 0)
 586                 goto out_major_mismatch;
 587
 588         dprintk("NFS: --> %s server owners match\n", __func__);
 589         return true;
 590
 591 out_major_mismatch:
 592         dprintk("NFS: --> %s server owner major IDs do not match\n",
 593                 __func__);
 594         return false;
 595 }
 596
 597 /**
 598  * nfs41_walk_client_list - Find nfs_client that matches a client/server owner
 599  *
 600  * @new: nfs_client with client ID to test
 601  * @result: OUT: found nfs_client, or new
 602  * @cred: credential to use for trunking test
 603  *
 604  * Returns zero, a negative errno, or a negative NFS4ERR status.
 605  * If zero is returned, an nfs_client pointer is planted in "result."
 606  *
 607  * NB: nfs41_walk_client_list() relies on the new nfs_client being
 608  *     the last nfs_client on the list.
 609  */
 610 int nfs41_walk_client_list(struct nfs_client *new,
 611                            struct nfs_client **result,
 612                            struct rpc_cred *cred)
 613 {
 614         struct nfs_net *nn = net_generic(new->cl_net, nfs_net_id);
 615         struct nfs_client *pos, *prev = NULL;
 616         int status = -NFS4ERR_STALE_CLIENTID;
 617
 618         spin_lock(&nn->nfs_client_lock);
 619         list_for_each_entry(pos, &nn->nfs_client_list, cl_share_link) {
 620
 621                 if (pos->rpc_ops != new->rpc_ops)
 622                         continue;
 623
 624                 if (pos->cl_proto != new->cl_proto)
 625                         continue;
 626
 627                 if (pos->cl_minorversion != new->cl_minorversion)
 628                         continue;
 629
 630                 /* If "pos" isn't marked ready, we can't trust the
 631                  * remaining fields in "pos", especially the client
 632                  * ID and serverowner fields.  Wait for CREATE_SESSION
 633                  * to finish. */
 634                 if (pos->cl_cons_state > NFS_CS_READY) {
 635                         atomic_inc(&pos->cl_count);
 636                         spin_unlock(&nn->nfs_client_lock);
 637
 638                         if (prev)
 639                                 nfs_put_client(prev);
 640                         prev = pos;
 641
 642                         status = nfs_wait_client_init_complete(pos);
 643                         if (pos->cl_cons_state == NFS_CS_SESSION_INITING) {
 644                                 nfs4_schedule_lease_recovery(pos);
 645                                 status = nfs4_wait_clnt_recover(pos);
 646                         }
 647                         spin_lock(&nn->nfs_client_lock);
 648                         if (status < 0)
 649                                 break;
 650                         status = -NFS4ERR_STALE_CLIENTID;
 651                 }
 652                 if (pos->cl_cons_state != NFS_CS_READY)
 653                         continue;
 654
 655                 if (!nfs4_match_clientids(pos, new))
 656                         continue;
 657
 658                 /*
 659                  * Note that session trunking is just a special subcase of
 660                  * client id trunking. In either case, we want to fall back
 661                  * to using the existing nfs_client.
 662                  */
 663                 if (!nfs4_check_clientid_trunking(pos, new))
 664                         continue;
 665
 666                 atomic_inc(&pos->cl_count);
 667                 *result = pos;
 668                 status = 0;
 669                 dprintk("NFS: <-- %s using nfs_client = %p ({%d})\n",
 670                         __func__, pos, atomic_read(&pos->cl_count));
 671                 break;
 672         }
 673
 674         /* No matching nfs_client found. */
 675         spin_unlock(&nn->nfs_client_lock);
 676         dprintk("NFS: <-- %s status = %d\n", __func__, status);
 677         if (prev)
 678                 nfs_put_client(prev);
 679         return status;
 680 }
 681 #endif  /* CONFIG_NFS_V4_1 */
 682
 683 static void nfs4_destroy_server(struct nfs_server *server)
 684 {
 685         nfs_server_return_all_delegations(server);
 686         unset_pnfs_layoutdriver(server);
 687         nfs4_purge_state_owners(server);
 688 }
 689
 690 /*
 691  * NFSv4.0 callback thread helper
 692  *
 693  * Find a client by callback identifier
 694  */
 695 struct nfs_client *
 696 nfs4_find_client_ident(struct net *net, int cb_ident)
 697 {
 698         struct nfs_client *clp;
 699         struct nfs_net *nn = net_generic(net, nfs_net_id);
 700
 701         spin_lock(&nn->nfs_client_lock);
 702         clp = idr_find(&nn->cb_ident_idr, cb_ident);
 703         if (clp)
 704                 atomic_inc(&clp->cl_count);
 705         spin_unlock(&nn->nfs_client_lock);
 706         return clp;
 707 }
 708
 709 #if defined(CONFIG_NFS_V4_1)
 710 /* Common match routine for v4.0 and v4.1 callback services */
 711 static bool nfs4_cb_match_client(const struct sockaddr *addr,
 712                 struct nfs_client *clp, u32 minorversion)
 713 {
 714         struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 715
 716         /* Don't match clients that failed to initialise */
 717         if (!(clp->cl_cons_state == NFS_CS_READY ||
 718             clp->cl_cons_state == NFS_CS_SESSION_INITING))
 719                 return false;
 720
 721         smp_rmb();
 722
 723         /* Match the version and minorversion */
 724         if (clp->rpc_ops->version != 4 ||
 725             clp->cl_minorversion != minorversion)
 726                 return false;
 727
 728         /* Match only the IP address, not the port number */
 729         if (!nfs_sockaddr_match_ipaddr(addr, clap))
 730                 return false;
 731
 732         return true;
 733 }
 734
 735 /*
 736  * NFSv4.1 callback thread helper
 737  * For CB_COMPOUND calls, find a client by IP address, protocol version,
 738  * minorversion, and sessionID
 739  *
 740  * Returns NULL if no such client
 741  */
 742 struct nfs_client *
 743 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 744                            struct nfs4_sessionid *sid, u32 minorversion)
 745 {
 746         struct nfs_client *clp;
 747         struct nfs_net *nn = net_generic(net, nfs_net_id);
 748
 749         spin_lock(&nn->nfs_client_lock);
 750         list_for_each_entry(clp, &nn->nfs_client_list, cl_share_link) {
 751                 if (nfs4_cb_match_client(addr, clp, minorversion) == false)
 752                         continue;
 753
 754                 if (!nfs4_has_session(clp))
 755                         continue;
 756
 757                 /* Match sessionid*/
 758                 if (memcmp(clp->cl_session->sess_id.data,
 759                     sid->data, NFS4_MAX_SESSIONID_LEN) != 0)
 760                         continue;
 761
 762                 atomic_inc(&clp->cl_count);
 763                 spin_unlock(&nn->nfs_client_lock);
 764                 return clp;
 765         }
 766         spin_unlock(&nn->nfs_client_lock);
 767         return NULL;
 768 }
 769
 770 #else /* CONFIG_NFS_V4_1 */
 771
 772 struct nfs_client *
 773 nfs4_find_client_sessionid(struct net *net, const struct sockaddr *addr,
 774                            struct nfs4_sessionid *sid, u32 minorversion)
 775 {
 776         return NULL;
 777 }
 778 #endif /* CONFIG_NFS_V4_1 */
 779
 780 /*
 781  * Set up an NFS4 client
 782  */
 783 static int nfs4_set_client(struct nfs_server *server,
 784                 const char *hostname,
 785                 const struct sockaddr *addr,
 786                 const size_t addrlen,
 787                 const char *ip_addr,
 788                 rpc_authflavor_t authflavour,
 789                 int proto, const struct rpc_timeout *timeparms,
 790                 u32 minorversion, struct net *net)
 791 {
 792         struct nfs_client_initdata cl_init = {
 793                 .hostname = hostname,
 794                 .addr = addr,
 795                 .addrlen = addrlen,
 796                 .nfs_mod = &nfs_v4,
 797                 .proto = proto,
 798                 .minorversion = minorversion,
 799                 .net = net,
 800         };
 801         struct nfs_client *clp;
 802         int error;
 803
 804         dprintk("--> nfs4_set_client()\n");
 805
 806         if (server->flags & NFS_MOUNT_NORESVPORT)
 807                 set_bit(NFS_CS_NORESVPORT, &cl_init.init_flags);
 808         if (server->options & NFS_OPTION_MIGRATION)
 809                 set_bit(NFS_CS_MIGRATION, &cl_init.init_flags);
 810
 811         /* Allocate or find a client reference we can use */
 812         clp = nfs_get_client(&cl_init, timeparms, ip_addr, authflavour);
 813         if (IS_ERR(clp)) {
 814                 error = PTR_ERR(clp);
 815                 goto error;
 816         }
 817
 818         /*
 819          * Query for the lease time on clientid setup or renewal
 820          *
 821          * Note that this will be set on nfs_clients that were created
 822          * only for the DS role and did not set this bit, but now will
 823          * serve a dual role.
 824          */
 825         set_bit(NFS_CS_CHECK_LEASE_TIME, &clp->cl_res_state);
 826
 827         server->nfs_client = clp;
 828         dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
 829         return 0;
 830 error:
 831         dprintk("<-- nfs4_set_client() = xerror %d\n", error);
 832         return error;
 833 }
 834
 835 /*
 836  * Set up a pNFS Data Server client.
 837  *
 838  * Return any existing nfs_client that matches server address,port,version
 839  * and minorversion.
 840  *
 841  * For a new nfs_client, use a soft mount (default), a low retrans and a
 842  * low timeout interval so that if a connection is lost, we retry through
 843  * the MDS.
 844  */
 845 struct nfs_client *nfs4_set_ds_client(struct nfs_client* mds_clp,
 846                 const struct sockaddr *ds_addr, int ds_addrlen,
 847                 int ds_proto, unsigned int ds_timeo, unsigned int ds_retrans)
 848 {
 849         struct nfs_client_initdata cl_init = {
 850                 .addr = ds_addr,
 851                 .addrlen = ds_addrlen,
 852                 .nfs_mod = &nfs_v4,
 853                 .proto = ds_proto,
 854                 .minorversion = mds_clp->cl_minorversion,
 855                 .net = mds_clp->cl_net,
 856         };
 857         struct rpc_timeout ds_timeout;
 858         struct nfs_client *clp;
 859
 860         /*
 861          * Set an authflavor equual to the MDS value. Use the MDS nfs_client
 862          * cl_ipaddr so as to use the same EXCHANGE_ID co_ownerid as the MDS
 863          * (section 13.1 RFC 5661).
 864          */
 865         nfs_init_timeout_values(&ds_timeout, ds_proto, ds_timeo, ds_retrans);
 866         clp = nfs_get_client(&cl_init, &ds_timeout, mds_clp->cl_ipaddr,
 867                              mds_clp->cl_rpcclient->cl_auth->au_flavor);
 868
 869         dprintk("<-- %s %p\n", __func__, clp);
 870         return clp;
 871 }
 872 EXPORT_SYMBOL_GPL(nfs4_set_ds_client);
 873
 874 /*
 875  * Session has been established, and the client marked ready.
 876  * Set the mount rsize and wsize with negotiated fore channel
 877  * attributes which will be bound checked in nfs_server_set_fsinfo.
 878  */
 879 static void nfs4_session_set_rwsize(struct nfs_server *server)
 880 {
 881 #ifdef CONFIG_NFS_V4_1
 882         struct nfs4_session *sess;
 883         u32 server_resp_sz;
 884         u32 server_rqst_sz;
 885
 886         if (!nfs4_has_session(server->nfs_client))
 887                 return;
 888         sess = server->nfs_client->cl_session;
 889         server_resp_sz = sess->fc_attrs.max_resp_sz - nfs41_maxread_overhead;
 890         server_rqst_sz = sess->fc_attrs.max_rqst_sz - nfs41_maxwrite_overhead;
 891
 892         if (server->rsize > server_resp_sz)
 893                 server->rsize = server_resp_sz;
 894         if (server->wsize > server_rqst_sz)
 895                 server->wsize = server_rqst_sz;
 896 #endif /* CONFIG_NFS_V4_1 */
 897 }
 898
 899 static int nfs4_server_common_setup(struct nfs_server *server,
 900                 struct nfs_fh *mntfh, bool auth_probe)
 901 {
 902         struct nfs_fattr *fattr;
 903         int error;
 904
 905         /* data servers support only a subset of NFSv4.1 */
 906         if (is_ds_only_client(server->nfs_client))
 907                 return -EPROTONOSUPPORT;
 908
 909         fattr = nfs_alloc_fattr();
 910         if (fattr == NULL)
 911                 return -ENOMEM;
 912
 913         /* We must ensure the session is initialised first */
 914         error = nfs4_init_session(server->nfs_client);
 915         if (error < 0)
 916                 goto out;
 917
 918         /* Set the basic capabilities */
 919         server->caps |= server->nfs_client->cl_mvops->init_caps;
 920         if (server->flags & NFS_MOUNT_NORDIRPLUS)
 921                         server->caps &= ~NFS_CAP_READDIRPLUS;
 922         /*
 923          * Don't use NFS uid/gid mapping if we're using AUTH_SYS or lower
 924          * authentication.
 925          */
 926         if (nfs4_disable_idmapping &&
 927                         server->client->cl_auth->au_flavor == RPC_AUTH_UNIX)
 928                 server->caps |= NFS_CAP_UIDGID_NOMAP;
 929
 930
 931         /* Probe the root fh to retrieve its FSID and filehandle */
 932         error = nfs4_get_rootfh(server, mntfh, auth_probe);
 933         if (error < 0)
 934                 goto out;
 935
 936         dprintk("Server FSID: %llx:%llx\n",
 937                         (unsigned long long) server->fsid.major,
 938                         (unsigned long long) server->fsid.minor);
 939         nfs_display_fhandle(mntfh, "Pseudo-fs root FH");
 940
 941         nfs4_session_set_rwsize(server);
 942
 943         error = nfs_probe_fsinfo(server, mntfh, fattr);
 944         if (error < 0)
 945                 goto out;
 946
 947         if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
 948                 server->namelen = NFS4_MAXNAMLEN;
 949
 950         nfs_server_insert_lists(server);
 951         server->mount_time = jiffies;
 952         server->destroy = nfs4_destroy_server;
 953 out:
 954         nfs_free_fattr(fattr);
 955         return error;
 956 }
 957
 958 /*
 959  * Create a version 4 volume record
 960  */
 961 static int nfs4_init_server(struct nfs_server *server,
 962                 struct nfs_parsed_mount_data *data)
 963 {
 964         struct rpc_timeout timeparms;
 965         int error;
 966
 967         dprintk("--> nfs4_init_server()\n");
 968
 969         nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
 970                         data->timeo, data->retrans);
 971
 972         /* Initialise the client representation from the mount data */
 973         server->flags = data->flags;
 974         server->options = data->options;
 975         server->auth_info = data->auth_info;
 976
 977         /* Use the first specified auth flavor. If this flavor isn't
 978          * allowed by the server, use the SECINFO path to try the
 979          * other specified flavors */
 980         if (data->auth_info.flavor_len >= 1)
 981                 data->selected_flavor = data->auth_info.flavors[0];
 982         else
 983                 data->selected_flavor = RPC_AUTH_UNIX;
 984
 985         /* Get a client record */
 986         error = nfs4_set_client(server,
 987                         data->nfs_server.hostname,
 988                         (const struct sockaddr *)&data->nfs_server.address,
 989                         data->nfs_server.addrlen,
 990                         data->client_address,
 991                         data->selected_flavor,
 992                         data->nfs_server.protocol,
 993                         &timeparms,
 994                         data->minorversion,
 995                         data->net);
 996         if (error < 0)
 997                 goto error;
 998
 999         if (data->rsize)
1000                 server->rsize = nfs_block_size(data->rsize, NULL);
1001         if (data->wsize)
1002                 server->wsize = nfs_block_size(data->wsize, NULL);
1003
1004         server->acregmin = data->acregmin * HZ;
1005         server->acregmax = data->acregmax * HZ;
1006         server->acdirmin = data->acdirmin * HZ;
1007         server->acdirmax = data->acdirmax * HZ;
1008
1009         server->port = data->nfs_server.port;
1010
1011         error = nfs_init_server_rpcclient(server, &timeparms,
1012                                           data->selected_flavor);
1013
1014 error:
1015         /* Done */
1016         dprintk("<-- nfs4_init_server() = %d\n", error);
1017         return error;
1018 }
1019
1020 /*
1021  * Create a version 4 volume record
1022  * - keyed on server and FSID
1023  */
1024 /*struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1025                                       struct nfs_fh *mntfh)*/
1026 struct nfs_server *nfs4_create_server(struct nfs_mount_info *mount_info,
1027                                       struct nfs_subversion *nfs_mod)
1028 {
1029         struct nfs_server *server;
1030         bool auth_probe;
1031         int error;
1032
1033         dprintk("--> nfs4_create_server()\n");
1034
1035         server = nfs_alloc_server();
1036         if (!server)
1037                 return ERR_PTR(-ENOMEM);
1038
1039         auth_probe = mount_info->parsed->auth_info.flavor_len < 1;
1040
1041         /* set up the general RPC client */
1042         error = nfs4_init_server(server, mount_info->parsed);
1043         if (error < 0)
1044                 goto error;
1045
1046         error = nfs4_server_common_setup(server, mount_info->mntfh, auth_probe);
1047         if (error < 0)
1048                 goto error;
1049
1050         dprintk("<-- nfs4_create_server() = %p\n", server);
1051         return server;
1052
1053 error:
1054         nfs_free_server(server);
1055         dprintk("<-- nfs4_create_server() = error %d\n", error);
1056         return ERR_PTR(error);
1057 }
1058
1059 /*
1060  * Create an NFS4 referral server record
1061  */
1062 struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1063                                                struct nfs_fh *mntfh)
1064 {
1065         struct nfs_client *parent_client;
1066         struct nfs_server *server, *parent_server;
1067         bool auth_probe;
1068         int error;
1069
1070         dprintk("--> nfs4_create_referral_server()\n");
1071
1072         server = nfs_alloc_server();
1073         if (!server)
1074                 return ERR_PTR(-ENOMEM);
1075
1076         parent_server = NFS_SB(data->sb);
1077         parent_client = parent_server->nfs_client;
1078
1079         /* Initialise the client representation from the parent server */
1080         nfs_server_copy_userdata(server, parent_server);
1081
1082         /* Get a client representation.
1083          * Note: NFSv4 always uses TCP, */
1084         error = nfs4_set_client(server, data->hostname,
1085                                 data->addr,
1086                                 data->addrlen,
1087                                 parent_client->cl_ipaddr,
1088                                 data->authflavor,
1089                                 rpc_protocol(parent_server->client),
1090                                 parent_server->client->cl_timeout,
1091                                 parent_client->cl_mvops->minor_version,
1092                                 parent_client->cl_net);
1093         if (error < 0)
1094                 goto error;
1095
1096         error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
1097         if (error < 0)
1098                 goto error;
1099
1100         auth_probe = parent_server->auth_info.flavor_len < 1;
1101
1102         error = nfs4_server_common_setup(server, mntfh, auth_probe);
1103         if (error < 0)
1104                 goto error;
1105
1106         dprintk("<-- nfs_create_referral_server() = %p\n", server);
1107         return server;
1108
1109 error:
1110         nfs_free_server(server);
1111         dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
1112         return ERR_PTR(error);
1113 }
1114
1115 /*
1116  * Grab the destination's particulars, including lease expiry time.
1117  *
1118  * Returns zero if probe succeeded and retrieved FSID matches the FSID
1119  * we have cached.
1120  */
1121 static int nfs_probe_destination(struct nfs_server *server)
1122 {
1123         struct inode *inode = server->super->s_root->d_inode;
1124         struct nfs_fattr *fattr;
1125         int error;
1126
1127         fattr = nfs_alloc_fattr();
1128         if (fattr == NULL)
1129                 return -ENOMEM;
1130
1131         /* Sanity: the probe won't work if the destination server
1132          * does not recognize the migrated FH. */
1133         error = nfs_probe_fsinfo(server, NFS_FH(inode), fattr);
1134
1135         nfs_free_fattr(fattr);
1136         return error;
1137 }
1138
1139 /**
1140  * nfs4_update_server - Move an nfs_server to a different nfs_client
1141  *
1142  * @server: represents FSID to be moved
1143  * @hostname: new end-point's hostname
1144  * @sap: new end-point's socket address
1145  * @salen: size of "sap"
1146  * @net: net namespace
1147  *
1148  * The nfs_server must be quiescent before this function is invoked.
1149  * Either its session is drained (NFSv4.1+), or its transport is
1150  * plugged and drained (NFSv4.0).
1151  *
1152  * Returns zero on success, or a negative errno value.
1153  */
1154 int nfs4_update_server(struct nfs_server *server, const char *hostname,
1155                        struct sockaddr *sap, size_t salen, struct net *net)
1156 {
1157         struct nfs_client *clp = server->nfs_client;
1158         struct rpc_clnt *clnt = server->client;
1159         struct xprt_create xargs = {
1160                 .ident          = clp->cl_proto,
1161                 .net            = net,
1162                 .dstaddr        = sap,
1163                 .addrlen        = salen,
1164                 .servername     = hostname,
1165         };
1166         char buf[INET6_ADDRSTRLEN + 1];
1167         struct sockaddr_storage address;
1168         struct sockaddr *localaddr = (struct sockaddr *)&address;
1169         int error;
1170
1171         dprintk("--> %s: move FSID %llx:%llx to \"%s\")\n", __func__,
1172                         (unsigned long long)server->fsid.major,
1173                         (unsigned long long)server->fsid.minor,
1174                         hostname);
1175
1176         error = rpc_switch_client_transport(clnt, &xargs, clnt->cl_timeout);
1177         if (error != 0) {
1178                 dprintk("<-- %s(): rpc_switch_client_transport returned %d\n",
1179                         __func__, error);
1180                 goto out;
1181         }
1182
1183         error = rpc_localaddr(clnt, localaddr, sizeof(address));
1184         if (error != 0) {
1185                 dprintk("<-- %s(): rpc_localaddr returned %d\n",
1186                         __func__, error);
1187                 goto out;
1188         }
1189
1190         error = -EAFNOSUPPORT;
1191         if (rpc_ntop(localaddr, buf, sizeof(buf)) == 0) {
1192                 dprintk("<-- %s(): rpc_ntop returned %d\n",
1193                         __func__, error);
1194                 goto out;
1195         }
1196
1197         nfs_server_remove_lists(server);
1198         error = nfs4_set_client(server, hostname, sap, salen, buf,
1199                                 clp->cl_rpcclient->cl_auth->au_flavor,
1200                                 clp->cl_proto, clnt->cl_timeout,
1201                                 clp->cl_minorversion, net);
1202         nfs_put_client(clp);
1203         if (error != 0) {
1204                 nfs_server_insert_lists(server);
1205                 dprintk("<-- %s(): nfs4_set_client returned %d\n",
1206                         __func__, error);
1207                 goto out;
1208         }
1209
1210         if (server->nfs_client->cl_hostname == NULL)
1211                 server->nfs_client->cl_hostname = kstrdup(hostname, GFP_KERNEL);
1212         nfs_server_insert_lists(server);
1213
1214         error = nfs_probe_destination(server);
1215         if (error < 0)
1216                 goto out;
1217
1218         dprintk("<-- %s() succeeded\n", __func__);
1219
1220 out:
1221         return error;
1222 }