fs/nfs/client.c

   1 /* client.c: NFS client sharing and management code
   2  *
   3  * Copyright (C) 2006 Red Hat, Inc. All Rights Reserved.
   4  * Written by David Howells (dhowells@redhat.com)
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License
   8  * as published by the Free Software Foundation; either version
   9  * 2 of the License, or (at your option) any later version.
  10  */
  11
  12
  13 #include <linux/module.h>
  14 #include <linux/init.h>
  15 #include <linux/sched.h>
  16 #include <linux/time.h>
  17 #include <linux/kernel.h>
  18 #include <linux/mm.h>
  19 #include <linux/string.h>
  20 #include <linux/stat.h>
  21 #include <linux/errno.h>
  22 #include <linux/unistd.h>
  23 #include <linux/sunrpc/clnt.h>
  24 #include <linux/sunrpc/stats.h>
  25 #include <linux/sunrpc/metrics.h>
  26 #include <linux/sunrpc/xprtsock.h>
  27 #include <linux/sunrpc/xprtrdma.h>
  28 #include <linux/nfs_fs.h>
  29 #include <linux/nfs_mount.h>
  30 #include <linux/nfs4_mount.h>
  31 #include <linux/lockd/bind.h>
  32 #include <linux/seq_file.h>
  33 #include <linux/mount.h>
  34 #include <linux/nfs_idmap.h>
  35 #include <linux/vfs.h>
  36 #include <linux/inet.h>
  37 #include <linux/in6.h>
  38 #include <net/ipv6.h>
  39 #include <linux/nfs_xdr.h>
  40
  41 #include <asm/system.h>
  42
  43 #include "nfs4_fs.h"
  44 #include "callback.h"
  45 #include "delegation.h"
  46 #include "iostat.h"
  47 #include "internal.h"
  48
  49 #define NFSDBG_FACILITY         NFSDBG_CLIENT
  50
  51 static DEFINE_SPINLOCK(nfs_client_lock);
  52 static LIST_HEAD(nfs_client_list);
  53 static LIST_HEAD(nfs_volume_list);
  54 static DECLARE_WAIT_QUEUE_HEAD(nfs_client_active_wq);
  55
  56 /*
  57  * RPC cruft for NFS
  58  */
  59 static struct rpc_version *nfs_version[5] = {
  60         [2]                     = &nfs_version2,
  61 #ifdef CONFIG_NFS_V3
  62         [3]                     = &nfs_version3,
  63 #endif
  64 #ifdef CONFIG_NFS_V4
  65         [4]                     = &nfs_version4,
  66 #endif
  67 };
  68
  69 struct rpc_program nfs_program = {
  70         .name                   = "nfs",
  71         .number                 = NFS_PROGRAM,
  72         .nrvers                 = ARRAY_SIZE(nfs_version),
  73         .version                = nfs_version,
  74         .stats                  = &nfs_rpcstat,
  75         .pipe_dir_name          = "/nfs",
  76 };
  77
  78 struct rpc_stat nfs_rpcstat = {
  79         .program                = &nfs_program
  80 };
  81
  82
  83 #ifdef CONFIG_NFS_V3_ACL
  84 static struct rpc_stat          nfsacl_rpcstat = { &nfsacl_program };
  85 static struct rpc_version *     nfsacl_version[] = {
  86         [3]                     = &nfsacl_version3,
  87 };
  88
  89 struct rpc_program              nfsacl_program = {
  90         .name                   = "nfsacl",
  91         .number                 = NFS_ACL_PROGRAM,
  92         .nrvers                 = ARRAY_SIZE(nfsacl_version),
  93         .version                = nfsacl_version,
  94         .stats                  = &nfsacl_rpcstat,
  95 };
  96 #endif  /* CONFIG_NFS_V3_ACL */
  97
  98 struct nfs_client_initdata {
  99         const char *hostname;
 100         const struct sockaddr *addr;
 101         size_t addrlen;
 102         const struct nfs_rpc_ops *rpc_ops;
 103         int proto;
 104 };
 105
 106 /*
 107  * Allocate a shared client record
 108  *
 109  * Since these are allocated/deallocated very rarely, we don't
 110  * bother putting them in a slab cache...
 111  */
 112 static struct nfs_client *nfs_alloc_client(const struct nfs_client_initdata *cl_init)
 113 {
 114         struct nfs_client *clp;
 115
 116         if ((clp = kzalloc(sizeof(*clp), GFP_KERNEL)) == NULL)
 117                 goto error_0;
 118
 119         clp->rpc_ops = cl_init->rpc_ops;
 120
 121         if (cl_init->rpc_ops->version == 4) {
 122                 if (nfs_callback_up() < 0)
 123                         goto error_2;
 124                 __set_bit(NFS_CS_CALLBACK, &clp->cl_res_state);
 125         }
 126
 127         atomic_set(&clp->cl_count, 1);
 128         clp->cl_cons_state = NFS_CS_INITING;
 129
 130         memcpy(&clp->cl_addr, cl_init->addr, cl_init->addrlen);
 131         clp->cl_addrlen = cl_init->addrlen;
 132
 133         if (cl_init->hostname) {
 134                 clp->cl_hostname = kstrdup(cl_init->hostname, GFP_KERNEL);
 135                 if (!clp->cl_hostname)
 136                         goto error_3;
 137         }
 138
 139         INIT_LIST_HEAD(&clp->cl_superblocks);
 140         clp->cl_rpcclient = ERR_PTR(-EINVAL);
 141
 142         clp->cl_proto = cl_init->proto;
 143
 144 #ifdef CONFIG_NFS_V4
 145         init_rwsem(&clp->cl_sem);
 146         INIT_LIST_HEAD(&clp->cl_delegations);
 147         spin_lock_init(&clp->cl_lock);
 148         INIT_DELAYED_WORK(&clp->cl_renewd, nfs4_renew_state);
 149         rpc_init_wait_queue(&clp->cl_rpcwaitq, "NFS client");
 150         clp->cl_boot_time = CURRENT_TIME;
 151         clp->cl_state = 1 << NFS4CLNT_LEASE_EXPIRED;
 152 #endif
 153
 154         return clp;
 155
 156 error_3:
 157         if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
 158                 nfs_callback_down();
 159 error_2:
 160         kfree(clp);
 161 error_0:
 162         return NULL;
 163 }
 164
 165 static void nfs4_shutdown_client(struct nfs_client *clp)
 166 {
 167 #ifdef CONFIG_NFS_V4
 168         if (__test_and_clear_bit(NFS_CS_RENEWD, &clp->cl_res_state))
 169                 nfs4_kill_renewd(clp);
 170         BUG_ON(!RB_EMPTY_ROOT(&clp->cl_state_owners));
 171         if (__test_and_clear_bit(NFS_CS_IDMAP, &clp->cl_res_state))
 172                 nfs_idmap_delete(clp);
 173 #endif
 174 }
 175
 176 /*
 177  * Destroy a shared client record
 178  */
 179 static void nfs_free_client(struct nfs_client *clp)
 180 {
 181         dprintk("--> nfs_free_client(%u)\n", clp->rpc_ops->version);
 182
 183         nfs4_shutdown_client(clp);
 184
 185         /* -EIO all pending I/O */
 186         if (!IS_ERR(clp->cl_rpcclient))
 187                 rpc_shutdown_client(clp->cl_rpcclient);
 188
 189         if (__test_and_clear_bit(NFS_CS_CALLBACK, &clp->cl_res_state))
 190                 nfs_callback_down();
 191
 192         kfree(clp->cl_hostname);
 193         kfree(clp);
 194
 195         dprintk("<-- nfs_free_client()\n");
 196 }
 197
 198 /*
 199  * Release a reference to a shared client record
 200  */
 201 void nfs_put_client(struct nfs_client *clp)
 202 {
 203         if (!clp)
 204                 return;
 205
 206         dprintk("--> nfs_put_client({%d})\n", atomic_read(&clp->cl_count));
 207
 208         if (atomic_dec_and_lock(&clp->cl_count, &nfs_client_lock)) {
 209                 list_del(&clp->cl_share_link);
 210                 spin_unlock(&nfs_client_lock);
 211
 212                 BUG_ON(!list_empty(&clp->cl_superblocks));
 213
 214                 nfs_free_client(clp);
 215         }
 216 }
 217
 218 static int nfs_sockaddr_match_ipaddr4(const struct sockaddr_in *sa1,
 219                                  const struct sockaddr_in *sa2)
 220 {
 221         return sa1->sin_addr.s_addr == sa2->sin_addr.s_addr;
 222 }
 223
 224 static int nfs_sockaddr_match_ipaddr6(const struct sockaddr_in6 *sa1,
 225                                  const struct sockaddr_in6 *sa2)
 226 {
 227         return ipv6_addr_equal(&sa1->sin6_addr, &sa2->sin6_addr);
 228 }
 229
 230 static int nfs_sockaddr_match_ipaddr(const struct sockaddr *sa1,
 231                                  const struct sockaddr *sa2)
 232 {
 233         switch (sa1->sa_family) {
 234         case AF_INET:
 235                 return nfs_sockaddr_match_ipaddr4((const struct sockaddr_in *)sa1,
 236                                 (const struct sockaddr_in *)sa2);
 237         case AF_INET6:
 238                 return nfs_sockaddr_match_ipaddr6((const struct sockaddr_in6 *)sa1,
 239                                 (const struct sockaddr_in6 *)sa2);
 240         }
 241         BUG();
 242 }
 243
 244 /*
 245  * Find a client by IP address and protocol version
 246  * - returns NULL if no such client
 247  */
 248 struct nfs_client *nfs_find_client(const struct sockaddr *addr, u32 nfsversion)
 249 {
 250         struct nfs_client *clp;
 251
 252         spin_lock(&nfs_client_lock);
 253         list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
 254                 struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 255
 256                 /* Don't match clients that failed to initialise properly */
 257                 if (clp->cl_cons_state != NFS_CS_READY)
 258                         continue;
 259
 260                 /* Different NFS versions cannot share the same nfs_client */
 261                 if (clp->rpc_ops->version != nfsversion)
 262                         continue;
 263
 264                 if (addr->sa_family != clap->sa_family)
 265                         continue;
 266                 /* Match only the IP address, not the port number */
 267                 if (!nfs_sockaddr_match_ipaddr(addr, clap))
 268                         continue;
 269
 270                 atomic_inc(&clp->cl_count);
 271                 spin_unlock(&nfs_client_lock);
 272                 return clp;
 273         }
 274         spin_unlock(&nfs_client_lock);
 275         return NULL;
 276 }
 277
 278 /*
 279  * Find a client by IP address and protocol version
 280  * - returns NULL if no such client
 281  */
 282 struct nfs_client *nfs_find_client_next(struct nfs_client *clp)
 283 {
 284         struct sockaddr *sap = (struct sockaddr *)&clp->cl_addr;
 285         u32 nfsvers = clp->rpc_ops->version;
 286
 287         spin_lock(&nfs_client_lock);
 288         list_for_each_entry_continue(clp, &nfs_client_list, cl_share_link) {
 289                 struct sockaddr *clap = (struct sockaddr *)&clp->cl_addr;
 290
 291                 /* Don't match clients that failed to initialise properly */
 292                 if (clp->cl_cons_state != NFS_CS_READY)
 293                         continue;
 294
 295                 /* Different NFS versions cannot share the same nfs_client */
 296                 if (clp->rpc_ops->version != nfsvers)
 297                         continue;
 298
 299                 if (sap->sa_family != clap->sa_family)
 300                         continue;
 301                 /* Match only the IP address, not the port number */
 302                 if (!nfs_sockaddr_match_ipaddr(sap, clap))
 303                         continue;
 304
 305                 atomic_inc(&clp->cl_count);
 306                 spin_unlock(&nfs_client_lock);
 307                 return clp;
 308         }
 309         spin_unlock(&nfs_client_lock);
 310         return NULL;
 311 }
 312
 313 /*
 314  * Find an nfs_client on the list that matches the initialisation data
 315  * that is supplied.
 316  */
 317 static struct nfs_client *nfs_match_client(const struct nfs_client_initdata *data)
 318 {
 319         struct nfs_client *clp;
 320
 321         list_for_each_entry(clp, &nfs_client_list, cl_share_link) {
 322                 /* Don't match clients that failed to initialise properly */
 323                 if (clp->cl_cons_state < 0)
 324                         continue;
 325
 326                 /* Different NFS versions cannot share the same nfs_client */
 327                 if (clp->rpc_ops != data->rpc_ops)
 328                         continue;
 329
 330                 if (clp->cl_proto != data->proto)
 331                         continue;
 332
 333                 /* Match the full socket address */
 334                 if (memcmp(&clp->cl_addr, data->addr, sizeof(clp->cl_addr)) != 0)
 335                         continue;
 336
 337                 atomic_inc(&clp->cl_count);
 338                 return clp;
 339         }
 340         return NULL;
 341 }
 342
 343 /*
 344  * Look up a client by IP address and protocol version
 345  * - creates a new record if one doesn't yet exist
 346  */
 347 static struct nfs_client *nfs_get_client(const struct nfs_client_initdata *cl_init)
 348 {
 349         struct nfs_client *clp, *new = NULL;
 350         int error;
 351
 352         dprintk("--> nfs_get_client(%s,v%u)\n",
 353                 cl_init->hostname ?: "", cl_init->rpc_ops->version);
 354
 355         /* see if the client already exists */
 356         do {
 357                 spin_lock(&nfs_client_lock);
 358
 359                 clp = nfs_match_client(cl_init);
 360                 if (clp)
 361                         goto found_client;
 362                 if (new)
 363                         goto install_client;
 364
 365                 spin_unlock(&nfs_client_lock);
 366
 367                 new = nfs_alloc_client(cl_init);
 368         } while (new);
 369
 370         return ERR_PTR(-ENOMEM);
 371
 372         /* install a new client and return with it unready */
 373 install_client:
 374         clp = new;
 375         list_add(&clp->cl_share_link, &nfs_client_list);
 376         spin_unlock(&nfs_client_lock);
 377         dprintk("--> nfs_get_client() = %p [new]\n", clp);
 378         return clp;
 379
 380         /* found an existing client
 381          * - make sure it's ready before returning
 382          */
 383 found_client:
 384         spin_unlock(&nfs_client_lock);
 385
 386         if (new)
 387                 nfs_free_client(new);
 388
 389         error = wait_event_killable(nfs_client_active_wq,
 390                                 clp->cl_cons_state != NFS_CS_INITING);
 391         if (error < 0) {
 392                 nfs_put_client(clp);
 393                 return ERR_PTR(-ERESTARTSYS);
 394         }
 395
 396         if (clp->cl_cons_state < NFS_CS_READY) {
 397                 error = clp->cl_cons_state;
 398                 nfs_put_client(clp);
 399                 return ERR_PTR(error);
 400         }
 401
 402         BUG_ON(clp->cl_cons_state != NFS_CS_READY);
 403
 404         dprintk("--> nfs_get_client() = %p [share]\n", clp);
 405         return clp;
 406 }
 407
 408 /*
 409  * Mark a server as ready or failed
 410  */
 411 static void nfs_mark_client_ready(struct nfs_client *clp, int state)
 412 {
 413         clp->cl_cons_state = state;
 414         wake_up_all(&nfs_client_active_wq);
 415 }
 416
 417 /*
 418  * Initialise the timeout values for a connection
 419  */
 420 static void nfs_init_timeout_values(struct rpc_timeout *to, int proto,
 421                                     unsigned int timeo, unsigned int retrans)
 422 {
 423         to->to_initval = timeo * HZ / 10;
 424         to->to_retries = retrans;
 425         if (!to->to_retries)
 426                 to->to_retries = 2;
 427
 428         switch (proto) {
 429         case XPRT_TRANSPORT_TCP:
 430         case XPRT_TRANSPORT_RDMA:
 431                 if (to->to_initval == 0)
 432                         to->to_initval = 60 * HZ;
 433                 if (to->to_initval > NFS_MAX_TCP_TIMEOUT)
 434                         to->to_initval = NFS_MAX_TCP_TIMEOUT;
 435                 to->to_increment = to->to_initval;
 436                 to->to_maxval = to->to_initval + (to->to_increment * to->to_retries);
 437                 if (to->to_maxval > NFS_MAX_TCP_TIMEOUT)
 438                         to->to_maxval = NFS_MAX_TCP_TIMEOUT;
 439                 if (to->to_maxval < to->to_initval)
 440                         to->to_maxval = to->to_initval;
 441                 to->to_exponential = 0;
 442                 break;
 443         case XPRT_TRANSPORT_UDP:
 444         default:
 445                 if (!to->to_initval)
 446                         to->to_initval = 11 * HZ / 10;
 447                 if (to->to_initval > NFS_MAX_UDP_TIMEOUT)
 448                         to->to_initval = NFS_MAX_UDP_TIMEOUT;
 449                 to->to_maxval = NFS_MAX_UDP_TIMEOUT;
 450                 to->to_exponential = 1;
 451                 break;
 452         }
 453 }
 454
 455 /*
 456  * Create an RPC client handle
 457  */
 458 static int nfs_create_rpc_client(struct nfs_client *clp,
 459                                  const struct rpc_timeout *timeparms,
 460                                  rpc_authflavor_t flavor,
 461                                  int flags)
 462 {
 463         struct rpc_clnt         *clnt = NULL;
 464         struct rpc_create_args args = {
 465                 .protocol       = clp->cl_proto,
 466                 .address        = (struct sockaddr *)&clp->cl_addr,
 467                 .addrsize       = clp->cl_addrlen,
 468                 .timeout        = timeparms,
 469                 .servername     = clp->cl_hostname,
 470                 .program        = &nfs_program,
 471                 .version        = clp->rpc_ops->version,
 472                 .authflavor     = flavor,
 473                 .flags          = flags,
 474         };
 475
 476         if (!IS_ERR(clp->cl_rpcclient))
 477                 return 0;
 478
 479         clnt = rpc_create(&args);
 480         if (IS_ERR(clnt)) {
 481                 dprintk("%s: cannot create RPC client. Error = %ld\n",
 482                                 __FUNCTION__, PTR_ERR(clnt));
 483                 return PTR_ERR(clnt);
 484         }
 485
 486         clp->cl_rpcclient = clnt;
 487         return 0;
 488 }
 489
 490 /*
 491  * Version 2 or 3 client destruction
 492  */
 493 static void nfs_destroy_server(struct nfs_server *server)
 494 {
 495         if (!(server->flags & NFS_MOUNT_NONLM))
 496                 nlmclnt_done(server->nlm_host);
 497 }
 498
 499 /*
 500  * Version 2 or 3 lockd setup
 501  */
 502 static int nfs_start_lockd(struct nfs_server *server)
 503 {
 504         struct nlm_host *host;
 505         struct nfs_client *clp = server->nfs_client;
 506         struct nlmclnt_initdata nlm_init = {
 507                 .hostname       = clp->cl_hostname,
 508                 .address        = (struct sockaddr *)&clp->cl_addr,
 509                 .addrlen        = clp->cl_addrlen,
 510                 .protocol       = server->flags & NFS_MOUNT_TCP ?
 511                                                 IPPROTO_TCP : IPPROTO_UDP,
 512                 .nfs_version    = clp->rpc_ops->version,
 513         };
 514
 515         if (nlm_init.nfs_version > 3)
 516                 return 0;
 517         if (server->flags & NFS_MOUNT_NONLM)
 518                 return 0;
 519
 520         host = nlmclnt_init(&nlm_init);
 521         if (IS_ERR(host))
 522                 return PTR_ERR(host);
 523
 524         server->nlm_host = host;
 525         server->destroy = nfs_destroy_server;
 526         return 0;
 527 }
 528
 529 /*
 530  * Initialise an NFSv3 ACL client connection
 531  */
 532 #ifdef CONFIG_NFS_V3_ACL
 533 static void nfs_init_server_aclclient(struct nfs_server *server)
 534 {
 535         if (server->nfs_client->rpc_ops->version != 3)
 536                 goto out_noacl;
 537         if (server->flags & NFS_MOUNT_NOACL)
 538                 goto out_noacl;
 539
 540         server->client_acl = rpc_bind_new_program(server->client, &nfsacl_program, 3);
 541         if (IS_ERR(server->client_acl))
 542                 goto out_noacl;
 543
 544         /* No errors! Assume that Sun nfsacls are supported */
 545         server->caps |= NFS_CAP_ACLS;
 546         return;
 547
 548 out_noacl:
 549         server->caps &= ~NFS_CAP_ACLS;
 550 }
 551 #else
 552 static inline void nfs_init_server_aclclient(struct nfs_server *server)
 553 {
 554         server->flags &= ~NFS_MOUNT_NOACL;
 555         server->caps &= ~NFS_CAP_ACLS;
 556 }
 557 #endif
 558
 559 /*
 560  * Create a general RPC client
 561  */
 562 static int nfs_init_server_rpcclient(struct nfs_server *server,
 563                 const struct rpc_timeout *timeo,
 564                 rpc_authflavor_t pseudoflavour)
 565 {
 566         struct nfs_client *clp = server->nfs_client;
 567
 568         server->client = rpc_clone_client(clp->cl_rpcclient);
 569         if (IS_ERR(server->client)) {
 570                 dprintk("%s: couldn't create rpc_client!\n", __FUNCTION__);
 571                 return PTR_ERR(server->client);
 572         }
 573
 574         memcpy(&server->client->cl_timeout_default,
 575                         timeo,
 576                         sizeof(server->client->cl_timeout_default));
 577         server->client->cl_timeout = &server->client->cl_timeout_default;
 578
 579         if (pseudoflavour != clp->cl_rpcclient->cl_auth->au_flavor) {
 580                 struct rpc_auth *auth;
 581
 582                 auth = rpcauth_create(pseudoflavour, server->client);
 583                 if (IS_ERR(auth)) {
 584                         dprintk("%s: couldn't create credcache!\n", __FUNCTION__);
 585                         return PTR_ERR(auth);
 586                 }
 587         }
 588         server->client->cl_softrtry = 0;
 589         if (server->flags & NFS_MOUNT_SOFT)
 590                 server->client->cl_softrtry = 1;
 591
 592         return 0;
 593 }
 594
 595 /*
 596  * Initialise an NFS2 or NFS3 client
 597  */
 598 static int nfs_init_client(struct nfs_client *clp,
 599                            const struct rpc_timeout *timeparms,
 600                            const struct nfs_parsed_mount_data *data)
 601 {
 602         int error;
 603
 604         if (clp->cl_cons_state == NFS_CS_READY) {
 605                 /* the client is already initialised */
 606                 dprintk("<-- nfs_init_client() = 0 [already %p]\n", clp);
 607                 return 0;
 608         }
 609
 610         /*
 611          * Create a client RPC handle for doing FSSTAT with UNIX auth only
 612          * - RFC 2623, sec 2.3.2
 613          */
 614         error = nfs_create_rpc_client(clp, timeparms, RPC_AUTH_UNIX, 0);
 615         if (error < 0)
 616                 goto error;
 617         nfs_mark_client_ready(clp, NFS_CS_READY);
 618         return 0;
 619
 620 error:
 621         nfs_mark_client_ready(clp, error);
 622         dprintk("<-- nfs_init_client() = xerror %d\n", error);
 623         return error;
 624 }
 625
 626 /*
 627  * Create a version 2 or 3 client
 628  */
 629 static int nfs_init_server(struct nfs_server *server,
 630                            const struct nfs_parsed_mount_data *data)
 631 {
 632         struct nfs_client_initdata cl_init = {
 633                 .hostname = data->nfs_server.hostname,
 634                 .addr = (const struct sockaddr *)&data->nfs_server.address,
 635                 .addrlen = data->nfs_server.addrlen,
 636                 .rpc_ops = &nfs_v2_clientops,
 637                 .proto = data->nfs_server.protocol,
 638         };
 639         struct rpc_timeout timeparms;
 640         struct nfs_client *clp;
 641         int error;
 642
 643         dprintk("--> nfs_init_server()\n");
 644
 645 #ifdef CONFIG_NFS_V3
 646         if (data->flags & NFS_MOUNT_VER3)
 647                 cl_init.rpc_ops = &nfs_v3_clientops;
 648 #endif
 649
 650         /* Allocate or find a client reference we can use */
 651         clp = nfs_get_client(&cl_init);
 652         if (IS_ERR(clp)) {
 653                 dprintk("<-- nfs_init_server() = error %ld\n", PTR_ERR(clp));
 654                 return PTR_ERR(clp);
 655         }
 656
 657         nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
 658                         data->timeo, data->retrans);
 659         error = nfs_init_client(clp, &timeparms, data);
 660         if (error < 0)
 661                 goto error;
 662
 663         server->nfs_client = clp;
 664
 665         /* Initialise the client representation from the mount data */
 666         server->flags = data->flags & NFS_MOUNT_FLAGMASK;
 667
 668         if (data->rsize)
 669                 server->rsize = nfs_block_size(data->rsize, NULL);
 670         if (data->wsize)
 671                 server->wsize = nfs_block_size(data->wsize, NULL);
 672
 673         server->acregmin = data->acregmin * HZ;
 674         server->acregmax = data->acregmax * HZ;
 675         server->acdirmin = data->acdirmin * HZ;
 676         server->acdirmax = data->acdirmax * HZ;
 677
 678         /* Start lockd here, before we might error out */
 679         error = nfs_start_lockd(server);
 680         if (error < 0)
 681                 goto error;
 682
 683         error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
 684         if (error < 0)
 685                 goto error;
 686
 687         server->namelen  = data->namlen;
 688         /* Create a client RPC handle for the NFSv3 ACL management interface */
 689         nfs_init_server_aclclient(server);
 690         dprintk("<-- nfs_init_server() = 0 [new %p]\n", clp);
 691         return 0;
 692
 693 error:
 694         server->nfs_client = NULL;
 695         nfs_put_client(clp);
 696         dprintk("<-- nfs_init_server() = xerror %d\n", error);
 697         return error;
 698 }
 699
 700 /*
 701  * Load up the server record from information gained in an fsinfo record
 702  */
 703 static void nfs_server_set_fsinfo(struct nfs_server *server, struct nfs_fsinfo *fsinfo)
 704 {
 705         unsigned long max_rpc_payload;
 706
 707         /* Work out a lot of parameters */
 708         if (server->rsize == 0)
 709                 server->rsize = nfs_block_size(fsinfo->rtpref, NULL);
 710         if (server->wsize == 0)
 711                 server->wsize = nfs_block_size(fsinfo->wtpref, NULL);
 712
 713         if (fsinfo->rtmax >= 512 && server->rsize > fsinfo->rtmax)
 714                 server->rsize = nfs_block_size(fsinfo->rtmax, NULL);
 715         if (fsinfo->wtmax >= 512 && server->wsize > fsinfo->wtmax)
 716                 server->wsize = nfs_block_size(fsinfo->wtmax, NULL);
 717
 718         max_rpc_payload = nfs_block_size(rpc_max_payload(server->client), NULL);
 719         if (server->rsize > max_rpc_payload)
 720                 server->rsize = max_rpc_payload;
 721         if (server->rsize > NFS_MAX_FILE_IO_SIZE)
 722                 server->rsize = NFS_MAX_FILE_IO_SIZE;
 723         server->rpages = (server->rsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
 724
 725         server->backing_dev_info.ra_pages = server->rpages * NFS_MAX_READAHEAD;
 726
 727         if (server->wsize > max_rpc_payload)
 728                 server->wsize = max_rpc_payload;
 729         if (server->wsize > NFS_MAX_FILE_IO_SIZE)
 730                 server->wsize = NFS_MAX_FILE_IO_SIZE;
 731         server->wpages = (server->wsize + PAGE_CACHE_SIZE - 1) >> PAGE_CACHE_SHIFT;
 732         server->wtmult = nfs_block_bits(fsinfo->wtmult, NULL);
 733
 734         server->dtsize = nfs_block_size(fsinfo->dtpref, NULL);
 735         if (server->dtsize > PAGE_CACHE_SIZE)
 736                 server->dtsize = PAGE_CACHE_SIZE;
 737         if (server->dtsize > server->rsize)
 738                 server->dtsize = server->rsize;
 739
 740         if (server->flags & NFS_MOUNT_NOAC) {
 741                 server->acregmin = server->acregmax = 0;
 742                 server->acdirmin = server->acdirmax = 0;
 743         }
 744
 745         server->maxfilesize = fsinfo->maxfilesize;
 746
 747         /* We're airborne Set socket buffersize */
 748         rpc_setbufsize(server->client, server->wsize + 100, server->rsize + 100);
 749 }
 750
 751 /*
 752  * Probe filesystem information, including the FSID on v2/v3
 753  */
 754 static int nfs_probe_fsinfo(struct nfs_server *server, struct nfs_fh *mntfh, struct nfs_fattr *fattr)
 755 {
 756         struct nfs_fsinfo fsinfo;
 757         struct nfs_client *clp = server->nfs_client;
 758         int error;
 759
 760         dprintk("--> nfs_probe_fsinfo()\n");
 761
 762         if (clp->rpc_ops->set_capabilities != NULL) {
 763                 error = clp->rpc_ops->set_capabilities(server, mntfh);
 764                 if (error < 0)
 765                         goto out_error;
 766         }
 767
 768         fsinfo.fattr = fattr;
 769         nfs_fattr_init(fattr);
 770         error = clp->rpc_ops->fsinfo(server, mntfh, &fsinfo);
 771         if (error < 0)
 772                 goto out_error;
 773
 774         nfs_server_set_fsinfo(server, &fsinfo);
 775         error = bdi_init(&server->backing_dev_info);
 776         if (error)
 777                 goto out_error;
 778
 779
 780         /* Get some general file system info */
 781         if (server->namelen == 0) {
 782                 struct nfs_pathconf pathinfo;
 783
 784                 pathinfo.fattr = fattr;
 785                 nfs_fattr_init(fattr);
 786
 787                 if (clp->rpc_ops->pathconf(server, mntfh, &pathinfo) >= 0)
 788                         server->namelen = pathinfo.max_namelen;
 789         }
 790
 791         dprintk("<-- nfs_probe_fsinfo() = 0\n");
 792         return 0;
 793
 794 out_error:
 795         dprintk("nfs_probe_fsinfo: error = %d\n", -error);
 796         return error;
 797 }
 798
 799 /*
 800  * Copy useful information when duplicating a server record
 801  */
 802 static void nfs_server_copy_userdata(struct nfs_server *target, struct nfs_server *source)
 803 {
 804         target->flags = source->flags;
 805         target->acregmin = source->acregmin;
 806         target->acregmax = source->acregmax;
 807         target->acdirmin = source->acdirmin;
 808         target->acdirmax = source->acdirmax;
 809         target->caps = source->caps;
 810 }
 811
 812 /*
 813  * Allocate and initialise a server record
 814  */
 815 static struct nfs_server *nfs_alloc_server(void)
 816 {
 817         struct nfs_server *server;
 818
 819         server = kzalloc(sizeof(struct nfs_server), GFP_KERNEL);
 820         if (!server)
 821                 return NULL;
 822
 823         server->client = server->client_acl = ERR_PTR(-EINVAL);
 824
 825         /* Zero out the NFS state stuff */
 826         INIT_LIST_HEAD(&server->client_link);
 827         INIT_LIST_HEAD(&server->master_link);
 828
 829         init_waitqueue_head(&server->active_wq);
 830         atomic_set(&server->active, 0);
 831
 832         server->io_stats = nfs_alloc_iostats();
 833         if (!server->io_stats) {
 834                 kfree(server);
 835                 return NULL;
 836         }
 837
 838         return server;
 839 }
 840
 841 /*
 842  * Free up a server record
 843  */
 844 void nfs_free_server(struct nfs_server *server)
 845 {
 846         dprintk("--> nfs_free_server()\n");
 847
 848         spin_lock(&nfs_client_lock);
 849         list_del(&server->client_link);
 850         list_del(&server->master_link);
 851         spin_unlock(&nfs_client_lock);
 852
 853         if (server->destroy != NULL)
 854                 server->destroy(server);
 855
 856         if (!IS_ERR(server->client_acl))
 857                 rpc_shutdown_client(server->client_acl);
 858         if (!IS_ERR(server->client))
 859                 rpc_shutdown_client(server->client);
 860
 861         nfs_put_client(server->nfs_client);
 862
 863         nfs_free_iostats(server->io_stats);
 864         bdi_destroy(&server->backing_dev_info);
 865         kfree(server);
 866         nfs_release_automount_timer();
 867         dprintk("<-- nfs_free_server()\n");
 868 }
 869
 870 /*
 871  * Create a version 2 or 3 volume record
 872  * - keyed on server and FSID
 873  */
 874 struct nfs_server *nfs_create_server(const struct nfs_parsed_mount_data *data,
 875                                      struct nfs_fh *mntfh)
 876 {
 877         struct nfs_server *server;
 878         struct nfs_fattr fattr;
 879         int error;
 880
 881         server = nfs_alloc_server();
 882         if (!server)
 883                 return ERR_PTR(-ENOMEM);
 884
 885         /* Get a client representation */
 886         error = nfs_init_server(server, data);
 887         if (error < 0)
 888                 goto error;
 889
 890         BUG_ON(!server->nfs_client);
 891         BUG_ON(!server->nfs_client->rpc_ops);
 892         BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
 893
 894         /* Probe the root fh to retrieve its FSID */
 895         error = nfs_probe_fsinfo(server, mntfh, &fattr);
 896         if (error < 0)
 897                 goto error;
 898         if (server->nfs_client->rpc_ops->version == 3) {
 899                 if (server->namelen == 0 || server->namelen > NFS3_MAXNAMLEN)
 900                         server->namelen = NFS3_MAXNAMLEN;
 901                 if (!(data->flags & NFS_MOUNT_NORDIRPLUS))
 902                         server->caps |= NFS_CAP_READDIRPLUS;
 903         } else {
 904                 if (server->namelen == 0 || server->namelen > NFS2_MAXNAMLEN)
 905                         server->namelen = NFS2_MAXNAMLEN;
 906         }
 907
 908         if (!(fattr.valid & NFS_ATTR_FATTR)) {
 909                 error = server->nfs_client->rpc_ops->getattr(server, mntfh, &fattr);
 910                 if (error < 0) {
 911                         dprintk("nfs_create_server: getattr error = %d\n", -error);
 912                         goto error;
 913                 }
 914         }
 915         memcpy(&server->fsid, &fattr.fsid, sizeof(server->fsid));
 916
 917         dprintk("Server FSID: %llx:%llx\n",
 918                 (unsigned long long) server->fsid.major,
 919                 (unsigned long long) server->fsid.minor);
 920
 921         BUG_ON(!server->nfs_client);
 922         BUG_ON(!server->nfs_client->rpc_ops);
 923         BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
 924
 925         spin_lock(&nfs_client_lock);
 926         list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
 927         list_add_tail(&server->master_link, &nfs_volume_list);
 928         spin_unlock(&nfs_client_lock);
 929
 930         server->mount_time = jiffies;
 931         return server;
 932
 933 error:
 934         nfs_free_server(server);
 935         return ERR_PTR(error);
 936 }
 937
 938 #ifdef CONFIG_NFS_V4
 939 /*
 940  * Initialise an NFS4 client record
 941  */
 942 static int nfs4_init_client(struct nfs_client *clp,
 943                 const struct rpc_timeout *timeparms,
 944                 const char *ip_addr,
 945                 rpc_authflavor_t authflavour)
 946 {
 947         int error;
 948
 949         if (clp->cl_cons_state == NFS_CS_READY) {
 950                 /* the client is initialised already */
 951                 dprintk("<-- nfs4_init_client() = 0 [already %p]\n", clp);
 952                 return 0;
 953         }
 954
 955         /* Check NFS protocol revision and initialize RPC op vector */
 956         clp->rpc_ops = &nfs_v4_clientops;
 957
 958         error = nfs_create_rpc_client(clp, timeparms, authflavour,
 959                                         RPC_CLNT_CREATE_DISCRTRY);
 960         if (error < 0)
 961                 goto error;
 962         memcpy(clp->cl_ipaddr, ip_addr, sizeof(clp->cl_ipaddr));
 963
 964         error = nfs_idmap_new(clp);
 965         if (error < 0) {
 966                 dprintk("%s: failed to create idmapper. Error = %d\n",
 967                         __FUNCTION__, error);
 968                 goto error;
 969         }
 970         __set_bit(NFS_CS_IDMAP, &clp->cl_res_state);
 971
 972         nfs_mark_client_ready(clp, NFS_CS_READY);
 973         return 0;
 974
 975 error:
 976         nfs_mark_client_ready(clp, error);
 977         dprintk("<-- nfs4_init_client() = xerror %d\n", error);
 978         return error;
 979 }
 980
 981 /*
 982  * Set up an NFS4 client
 983  */
 984 static int nfs4_set_client(struct nfs_server *server,
 985                 const char *hostname,
 986                 const struct sockaddr *addr,
 987                 const size_t addrlen,
 988                 const char *ip_addr,
 989                 rpc_authflavor_t authflavour,
 990                 int proto, const struct rpc_timeout *timeparms)
 991 {
 992         struct nfs_client_initdata cl_init = {
 993                 .hostname = hostname,
 994                 .addr = addr,
 995                 .addrlen = addrlen,
 996                 .rpc_ops = &nfs_v4_clientops,
 997                 .proto = proto,
 998         };
 999         struct nfs_client *clp;
1000         int error;
1001
1002         dprintk("--> nfs4_set_client()\n");
1003
1004         /* Allocate or find a client reference we can use */
1005         clp = nfs_get_client(&cl_init);
1006         if (IS_ERR(clp)) {
1007                 error = PTR_ERR(clp);
1008                 goto error;
1009         }
1010         error = nfs4_init_client(clp, timeparms, ip_addr, authflavour);
1011         if (error < 0)
1012                 goto error_put;
1013
1014         server->nfs_client = clp;
1015         dprintk("<-- nfs4_set_client() = 0 [new %p]\n", clp);
1016         return 0;
1017
1018 error_put:
1019         nfs_put_client(clp);
1020 error:
1021         dprintk("<-- nfs4_set_client() = xerror %d\n", error);
1022         return error;
1023 }
1024
1025 /*
1026  * Create a version 4 volume record
1027  */
1028 static int nfs4_init_server(struct nfs_server *server,
1029                 const struct nfs_parsed_mount_data *data)
1030 {
1031         struct rpc_timeout timeparms;
1032         int error;
1033
1034         dprintk("--> nfs4_init_server()\n");
1035
1036         nfs_init_timeout_values(&timeparms, data->nfs_server.protocol,
1037                         data->timeo, data->retrans);
1038
1039         /* Get a client record */
1040         error = nfs4_set_client(server,
1041                         data->nfs_server.hostname,
1042                         (const struct sockaddr *)&data->nfs_server.address,
1043                         data->nfs_server.addrlen,
1044                         data->client_address,
1045                         data->auth_flavors[0],
1046                         data->nfs_server.protocol,
1047                         &timeparms);
1048         if (error < 0)
1049                 goto error;
1050
1051         /* Initialise the client representation from the mount data */
1052         server->flags = data->flags & NFS_MOUNT_FLAGMASK;
1053         server->caps |= NFS_CAP_ATOMIC_OPEN;
1054
1055         if (data->rsize)
1056                 server->rsize = nfs_block_size(data->rsize, NULL);
1057         if (data->wsize)
1058                 server->wsize = nfs_block_size(data->wsize, NULL);
1059
1060         server->acregmin = data->acregmin * HZ;
1061         server->acregmax = data->acregmax * HZ;
1062         server->acdirmin = data->acdirmin * HZ;
1063         server->acdirmax = data->acdirmax * HZ;
1064
1065         error = nfs_init_server_rpcclient(server, &timeparms, data->auth_flavors[0]);
1066
1067 error:
1068         /* Done */
1069         dprintk("<-- nfs4_init_server() = %d\n", error);
1070         return error;
1071 }
1072
1073 /*
1074  * Create a version 4 volume record
1075  * - keyed on server and FSID
1076  */
1077 struct nfs_server *nfs4_create_server(const struct nfs_parsed_mount_data *data,
1078                                       struct nfs_fh *mntfh)
1079 {
1080         struct nfs_fattr fattr;
1081         struct nfs_server *server;
1082         int error;
1083
1084         dprintk("--> nfs4_create_server()\n");
1085
1086         server = nfs_alloc_server();
1087         if (!server)
1088                 return ERR_PTR(-ENOMEM);
1089
1090         /* set up the general RPC client */
1091         error = nfs4_init_server(server, data);
1092         if (error < 0)
1093                 goto error;
1094
1095         BUG_ON(!server->nfs_client);
1096         BUG_ON(!server->nfs_client->rpc_ops);
1097         BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1098
1099         /* Probe the root fh to retrieve its FSID */
1100         error = nfs4_path_walk(server, mntfh, data->nfs_server.export_path);
1101         if (error < 0)
1102                 goto error;
1103
1104         dprintk("Server FSID: %llx:%llx\n",
1105                 (unsigned long long) server->fsid.major,
1106                 (unsigned long long) server->fsid.minor);
1107         dprintk("Mount FH: %d\n", mntfh->size);
1108
1109         error = nfs_probe_fsinfo(server, mntfh, &fattr);
1110         if (error < 0)
1111                 goto error;
1112
1113         if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1114                 server->namelen = NFS4_MAXNAMLEN;
1115
1116         BUG_ON(!server->nfs_client);
1117         BUG_ON(!server->nfs_client->rpc_ops);
1118         BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1119
1120         spin_lock(&nfs_client_lock);
1121         list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1122         list_add_tail(&server->master_link, &nfs_volume_list);
1123         spin_unlock(&nfs_client_lock);
1124
1125         server->mount_time = jiffies;
1126         dprintk("<-- nfs4_create_server() = %p\n", server);
1127         return server;
1128
1129 error:
1130         nfs_free_server(server);
1131         dprintk("<-- nfs4_create_server() = error %d\n", error);
1132         return ERR_PTR(error);
1133 }
1134
1135 /*
1136  * Create an NFS4 referral server record
1137  */
1138 struct nfs_server *nfs4_create_referral_server(struct nfs_clone_mount *data,
1139                                                struct nfs_fh *mntfh)
1140 {
1141         struct nfs_client *parent_client;
1142         struct nfs_server *server, *parent_server;
1143         struct nfs_fattr fattr;
1144         int error;
1145
1146         dprintk("--> nfs4_create_referral_server()\n");
1147
1148         server = nfs_alloc_server();
1149         if (!server)
1150                 return ERR_PTR(-ENOMEM);
1151
1152         parent_server = NFS_SB(data->sb);
1153         parent_client = parent_server->nfs_client;
1154
1155         /* Get a client representation.
1156          * Note: NFSv4 always uses TCP, */
1157         error = nfs4_set_client(server, data->hostname,
1158                                 data->addr,
1159                                 data->addrlen,
1160                                 parent_client->cl_ipaddr,
1161                                 data->authflavor,
1162                                 parent_server->client->cl_xprt->prot,
1163                                 parent_server->client->cl_timeout);
1164         if (error < 0)
1165                 goto error;
1166
1167         /* Initialise the client representation from the parent server */
1168         nfs_server_copy_userdata(server, parent_server);
1169         server->caps |= NFS_CAP_ATOMIC_OPEN;
1170
1171         error = nfs_init_server_rpcclient(server, parent_server->client->cl_timeout, data->authflavor);
1172         if (error < 0)
1173                 goto error;
1174
1175         BUG_ON(!server->nfs_client);
1176         BUG_ON(!server->nfs_client->rpc_ops);
1177         BUG_ON(!server->nfs_client->rpc_ops->file_inode_ops);
1178
1179         /* Probe the root fh to retrieve its FSID and filehandle */
1180         error = nfs4_path_walk(server, mntfh, data->mnt_path);
1181         if (error < 0)
1182                 goto error;
1183
1184         /* probe the filesystem info for this server filesystem */
1185         error = nfs_probe_fsinfo(server, mntfh, &fattr);
1186         if (error < 0)
1187                 goto error;
1188
1189         if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1190                 server->namelen = NFS4_MAXNAMLEN;
1191
1192         dprintk("Referral FSID: %llx:%llx\n",
1193                 (unsigned long long) server->fsid.major,
1194                 (unsigned long long) server->fsid.minor);
1195
1196         spin_lock(&nfs_client_lock);
1197         list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1198         list_add_tail(&server->master_link, &nfs_volume_list);
1199         spin_unlock(&nfs_client_lock);
1200
1201         server->mount_time = jiffies;
1202
1203         dprintk("<-- nfs_create_referral_server() = %p\n", server);
1204         return server;
1205
1206 error:
1207         nfs_free_server(server);
1208         dprintk("<-- nfs4_create_referral_server() = error %d\n", error);
1209         return ERR_PTR(error);
1210 }
1211
1212 #endif /* CONFIG_NFS_V4 */
1213
1214 /*
1215  * Clone an NFS2, NFS3 or NFS4 server record
1216  */
1217 struct nfs_server *nfs_clone_server(struct nfs_server *source,
1218                                     struct nfs_fh *fh,
1219                                     struct nfs_fattr *fattr)
1220 {
1221         struct nfs_server *server;
1222         struct nfs_fattr fattr_fsinfo;
1223         int error;
1224
1225         dprintk("--> nfs_clone_server(,%llx:%llx,)\n",
1226                 (unsigned long long) fattr->fsid.major,
1227                 (unsigned long long) fattr->fsid.minor);
1228
1229         server = nfs_alloc_server();
1230         if (!server)
1231                 return ERR_PTR(-ENOMEM);
1232
1233         /* Copy data from the source */
1234         server->nfs_client = source->nfs_client;
1235         atomic_inc(&server->nfs_client->cl_count);
1236         nfs_server_copy_userdata(server, source);
1237
1238         server->fsid = fattr->fsid;
1239
1240         error = nfs_init_server_rpcclient(server,
1241                         source->client->cl_timeout,
1242                         source->client->cl_auth->au_flavor);
1243         if (error < 0)
1244                 goto out_free_server;
1245         if (!IS_ERR(source->client_acl))
1246                 nfs_init_server_aclclient(server);
1247
1248         /* probe the filesystem info for this server filesystem */
1249         error = nfs_probe_fsinfo(server, fh, &fattr_fsinfo);
1250         if (error < 0)
1251                 goto out_free_server;
1252
1253         if (server->namelen == 0 || server->namelen > NFS4_MAXNAMLEN)
1254                 server->namelen = NFS4_MAXNAMLEN;
1255
1256         dprintk("Cloned FSID: %llx:%llx\n",
1257                 (unsigned long long) server->fsid.major,
1258                 (unsigned long long) server->fsid.minor);
1259
1260         error = nfs_start_lockd(server);
1261         if (error < 0)
1262                 goto out_free_server;
1263
1264         spin_lock(&nfs_client_lock);
1265         list_add_tail(&server->client_link, &server->nfs_client->cl_superblocks);
1266         list_add_tail(&server->master_link, &nfs_volume_list);
1267         spin_unlock(&nfs_client_lock);
1268
1269         server->mount_time = jiffies;
1270
1271         dprintk("<-- nfs_clone_server() = %p\n", server);
1272         return server;
1273
1274 out_free_server:
1275         nfs_free_server(server);
1276         dprintk("<-- nfs_clone_server() = error %d\n", error);
1277         return ERR_PTR(error);
1278 }
1279
1280 #ifdef CONFIG_PROC_FS
1281 static struct proc_dir_entry *proc_fs_nfs;
1282
1283 static int nfs_server_list_open(struct inode *inode, struct file *file);
1284 static void *nfs_server_list_start(struct seq_file *p, loff_t *pos);
1285 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos);
1286 static void nfs_server_list_stop(struct seq_file *p, void *v);
1287 static int nfs_server_list_show(struct seq_file *m, void *v);
1288
1289 static struct seq_operations nfs_server_list_ops = {
1290         .start  = nfs_server_list_start,
1291         .next   = nfs_server_list_next,
1292         .stop   = nfs_server_list_stop,
1293         .show   = nfs_server_list_show,
1294 };
1295
1296 static const struct file_operations nfs_server_list_fops = {
1297         .open           = nfs_server_list_open,
1298         .read           = seq_read,
1299         .llseek         = seq_lseek,
1300         .release        = seq_release,
1301 };
1302
1303 static int nfs_volume_list_open(struct inode *inode, struct file *file);
1304 static void *nfs_volume_list_start(struct seq_file *p, loff_t *pos);
1305 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos);
1306 static void nfs_volume_list_stop(struct seq_file *p, void *v);
1307 static int nfs_volume_list_show(struct seq_file *m, void *v);
1308
1309 static struct seq_operations nfs_volume_list_ops = {
1310         .start  = nfs_volume_list_start,
1311         .next   = nfs_volume_list_next,
1312         .stop   = nfs_volume_list_stop,
1313         .show   = nfs_volume_list_show,
1314 };
1315
1316 static const struct file_operations nfs_volume_list_fops = {
1317         .open           = nfs_volume_list_open,
1318         .read           = seq_read,
1319         .llseek         = seq_lseek,
1320         .release        = seq_release,
1321 };
1322
1323 /*
1324  * open "/proc/fs/nfsfs/servers" which provides a summary of servers with which
1325  * we're dealing
1326  */
1327 static int nfs_server_list_open(struct inode *inode, struct file *file)
1328 {
1329         struct seq_file *m;
1330         int ret;
1331
1332         ret = seq_open(file, &nfs_server_list_ops);
1333         if (ret < 0)
1334                 return ret;
1335
1336         m = file->private_data;
1337         m->private = PDE(inode)->data;
1338
1339         return 0;
1340 }
1341
1342 /*
1343  * set up the iterator to start reading from the server list and return the first item
1344  */
1345 static void *nfs_server_list_start(struct seq_file *m, loff_t *_pos)
1346 {
1347         /* lock the list against modification */
1348         spin_lock(&nfs_client_lock);
1349         return seq_list_start_head(&nfs_client_list, *_pos);
1350 }
1351
1352 /*
1353  * move to next server
1354  */
1355 static void *nfs_server_list_next(struct seq_file *p, void *v, loff_t *pos)
1356 {
1357         return seq_list_next(v, &nfs_client_list, pos);
1358 }
1359
1360 /*
1361  * clean up after reading from the transports list
1362  */
1363 static void nfs_server_list_stop(struct seq_file *p, void *v)
1364 {
1365         spin_unlock(&nfs_client_lock);
1366 }
1367
1368 /*
1369  * display a header line followed by a load of call lines
1370  */
1371 static int nfs_server_list_show(struct seq_file *m, void *v)
1372 {
1373         struct nfs_client *clp;
1374
1375         /* display header on line 1 */
1376         if (v == &nfs_client_list) {
1377                 seq_puts(m, "NV SERVER   PORT USE HOSTNAME\n");
1378                 return 0;
1379         }
1380
1381         /* display one transport per line on subsequent lines */
1382         clp = list_entry(v, struct nfs_client, cl_share_link);
1383
1384         seq_printf(m, "v%u %s %s %3d %s\n",
1385                    clp->rpc_ops->version,
1386                    rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1387                    rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1388                    atomic_read(&clp->cl_count),
1389                    clp->cl_hostname);
1390
1391         return 0;
1392 }
1393
1394 /*
1395  * open "/proc/fs/nfsfs/volumes" which provides a summary of extant volumes
1396  */
1397 static int nfs_volume_list_open(struct inode *inode, struct file *file)
1398 {
1399         struct seq_file *m;
1400         int ret;
1401
1402         ret = seq_open(file, &nfs_volume_list_ops);
1403         if (ret < 0)
1404                 return ret;
1405
1406         m = file->private_data;
1407         m->private = PDE(inode)->data;
1408
1409         return 0;
1410 }
1411
1412 /*
1413  * set up the iterator to start reading from the volume list and return the first item
1414  */
1415 static void *nfs_volume_list_start(struct seq_file *m, loff_t *_pos)
1416 {
1417         /* lock the list against modification */
1418         spin_lock(&nfs_client_lock);
1419         return seq_list_start_head(&nfs_volume_list, *_pos);
1420 }
1421
1422 /*
1423  * move to next volume
1424  */
1425 static void *nfs_volume_list_next(struct seq_file *p, void *v, loff_t *pos)
1426 {
1427         return seq_list_next(v, &nfs_volume_list, pos);
1428 }
1429
1430 /*
1431  * clean up after reading from the transports list
1432  */
1433 static void nfs_volume_list_stop(struct seq_file *p, void *v)
1434 {
1435         spin_unlock(&nfs_client_lock);
1436 }
1437
1438 /*
1439  * display a header line followed by a load of call lines
1440  */
1441 static int nfs_volume_list_show(struct seq_file *m, void *v)
1442 {
1443         struct nfs_server *server;
1444         struct nfs_client *clp;
1445         char dev[8], fsid[17];
1446
1447         /* display header on line 1 */
1448         if (v == &nfs_volume_list) {
1449                 seq_puts(m, "NV SERVER   PORT DEV     FSID\n");
1450                 return 0;
1451         }
1452         /* display one transport per line on subsequent lines */
1453         server = list_entry(v, struct nfs_server, master_link);
1454         clp = server->nfs_client;
1455
1456         snprintf(dev, 8, "%u:%u",
1457                  MAJOR(server->s_dev), MINOR(server->s_dev));
1458
1459         snprintf(fsid, 17, "%llx:%llx",
1460                  (unsigned long long) server->fsid.major,
1461                  (unsigned long long) server->fsid.minor);
1462
1463         seq_printf(m, "v%u %s %s %-7s %-17s\n",
1464                    clp->rpc_ops->version,
1465                    rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_ADDR),
1466                    rpc_peeraddr2str(clp->cl_rpcclient, RPC_DISPLAY_HEX_PORT),
1467                    dev,
1468                    fsid);
1469
1470         return 0;
1471 }
1472
1473 /*
1474  * initialise the /proc/fs/nfsfs/ directory
1475  */
1476 int __init nfs_fs_proc_init(void)
1477 {
1478         struct proc_dir_entry *p;
1479
1480         proc_fs_nfs = proc_mkdir("nfsfs", proc_root_fs);
1481         if (!proc_fs_nfs)
1482                 goto error_0;
1483
1484         proc_fs_nfs->owner = THIS_MODULE;
1485
1486         /* a file of servers with which we're dealing */
1487         p = create_proc_entry("servers", S_IFREG|S_IRUGO, proc_fs_nfs);
1488         if (!p)
1489                 goto error_1;
1490
1491         p->proc_fops = &nfs_server_list_fops;
1492         p->owner = THIS_MODULE;
1493
1494         /* a file of volumes that we have mounted */
1495         p = create_proc_entry("volumes", S_IFREG|S_IRUGO, proc_fs_nfs);
1496         if (!p)
1497                 goto error_2;
1498
1499         p->proc_fops = &nfs_volume_list_fops;
1500         p->owner = THIS_MODULE;
1501         return 0;
1502
1503 error_2:
1504         remove_proc_entry("servers", proc_fs_nfs);
1505 error_1:
1506         remove_proc_entry("nfsfs", proc_root_fs);
1507 error_0:
1508         return -ENOMEM;
1509 }
1510
1511 /*
1512  * clean up the /proc/fs/nfsfs/ directory
1513  */
1514 void nfs_fs_proc_exit(void)
1515 {
1516         remove_proc_entry("volumes", proc_fs_nfs);
1517         remove_proc_entry("servers", proc_fs_nfs);
1518         remove_proc_entry("nfsfs", proc_root_fs);
1519 }
1520
1521 #endif /* CONFIG_PROC_FS */