1/* 2 * Central processing for nfsd. 3 * 4 * Authors: Olaf Kirch (okir@monad.swb.de) 5 * 6 * Copyright (C) 1995, 1996, 1997 Olaf Kirch <okir@monad.swb.de> 7 */ 8 9#include <linux/sched.h> 10#include <linux/freezer.h> 11#include <linux/module.h> 12#include <linux/fs_struct.h> 13#include <linux/swap.h> 14 15#include <linux/sunrpc/stats.h> 16#include <linux/sunrpc/svcsock.h> 17#include <linux/lockd/bind.h> 18#include <linux/nfsacl.h> 19#include <linux/seq_file.h> 20#include <net/net_namespace.h> 21#include "nfsd.h" 22#include "cache.h" 23#include "vfs.h" 24#include "netns.h" 25 26#define NFSDDBG_FACILITY NFSDDBG_SVC 27 28extern struct svc_program nfsd_program; 29static int nfsd(void *vrqstp); 30 31/* 32 * nfsd_mutex protects nn->nfsd_serv -- both the pointer itself and the members 33 * of the svc_serv struct. In particular, ->sv_nrthreads but also to some 34 * extent ->sv_temp_socks and ->sv_permsocks. It also protects nfsdstats.th_cnt 35 * 36 * If (out side the lock) nn->nfsd_serv is non-NULL, then it must point to a 37 * properly initialised 'struct svc_serv' with ->sv_nrthreads > 0. That number 38 * of nfsd threads must exist and each must listed in ->sp_all_threads in each 39 * entry of ->sv_pools[]. 40 * 41 * Transitions of the thread count between zero and non-zero are of particular 42 * interest since the svc_serv needs to be created and initialized at that 43 * point, or freed. 44 * 45 * Finally, the nfsd_mutex also protects some of the global variables that are 46 * accessed when nfsd starts and that are settable via the write_* routines in 47 * nfsctl.c. In particular: 48 * 49 * user_recovery_dirname 50 * user_lease_time 51 * nfsd_versions 52 */ 53DEFINE_MUTEX(nfsd_mutex); 54 55/* 56 * nfsd_drc_lock protects nfsd_drc_max_pages and nfsd_drc_pages_used. 57 * nfsd_drc_max_pages limits the total amount of memory available for 58 * version 4.1 DRC caches. 59 * nfsd_drc_pages_used tracks the current version 4.1 DRC memory usage. 60 */ 61spinlock_t nfsd_drc_lock; 62unsigned long nfsd_drc_max_mem; 63unsigned long nfsd_drc_mem_used; 64 65#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 66static struct svc_stat nfsd_acl_svcstats; 67static struct svc_version * nfsd_acl_version[] = { 68 [2] = &nfsd_acl_version2, 69 [3] = &nfsd_acl_version3, 70}; 71 72#define NFSD_ACL_MINVERS 2 73#define NFSD_ACL_NRVERS ARRAY_SIZE(nfsd_acl_version) 74static struct svc_version *nfsd_acl_versions[NFSD_ACL_NRVERS]; 75 76static struct svc_program nfsd_acl_program = { 77 .pg_prog = NFS_ACL_PROGRAM, 78 .pg_nvers = NFSD_ACL_NRVERS, 79 .pg_vers = nfsd_acl_versions, 80 .pg_name = "nfsacl", 81 .pg_class = "nfsd", 82 .pg_stats = &nfsd_acl_svcstats, 83 .pg_authenticate = &svc_set_client, 84}; 85 86static struct svc_stat nfsd_acl_svcstats = { 87 .program = &nfsd_acl_program, 88}; 89#endif /* defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) */ 90 91static struct svc_version * nfsd_version[] = { 92 [2] = &nfsd_version2, 93#if defined(CONFIG_NFSD_V3) 94 [3] = &nfsd_version3, 95#endif 96#if defined(CONFIG_NFSD_V4) 97 [4] = &nfsd_version4, 98#endif 99}; 100 101#define NFSD_MINVERS 2 102#define NFSD_NRVERS ARRAY_SIZE(nfsd_version) 103static struct svc_version *nfsd_versions[NFSD_NRVERS]; 104 105struct svc_program nfsd_program = { 106#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 107 .pg_next = &nfsd_acl_program, 108#endif 109 .pg_prog = NFS_PROGRAM, /* program number */ 110 .pg_nvers = NFSD_NRVERS, /* nr of entries in nfsd_version */ 111 .pg_vers = nfsd_versions, /* version table */ 112 .pg_name = "nfsd", /* program name */ 113 .pg_class = "nfsd", /* authentication class */ 114 .pg_stats = &nfsd_svcstats, /* version table */ 115 .pg_authenticate = &svc_set_client, /* export authentication */ 116 117}; 118 119static bool nfsd_supported_minorversions[NFSD_SUPPORTED_MINOR_VERSION + 1] = { 120 [0] = 1, 121 [1] = 1, 122}; 123 124int nfsd_vers(int vers, enum vers_op change) 125{ 126 if (vers < NFSD_MINVERS || vers >= NFSD_NRVERS) 127 return 0; 128 switch(change) { 129 case NFSD_SET: 130 nfsd_versions[vers] = nfsd_version[vers]; 131#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 132 if (vers < NFSD_ACL_NRVERS) 133 nfsd_acl_versions[vers] = nfsd_acl_version[vers]; 134#endif 135 break; 136 case NFSD_CLEAR: 137 nfsd_versions[vers] = NULL; 138#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 139 if (vers < NFSD_ACL_NRVERS) 140 nfsd_acl_versions[vers] = NULL; 141#endif 142 break; 143 case NFSD_TEST: 144 return nfsd_versions[vers] != NULL; 145 case NFSD_AVAIL: 146 return nfsd_version[vers] != NULL; 147 } 148 return 0; 149} 150 151int nfsd_minorversion(u32 minorversion, enum vers_op change) 152{ 153 if (minorversion > NFSD_SUPPORTED_MINOR_VERSION) 154 return -1; 155 switch(change) { 156 case NFSD_SET: 157 nfsd_supported_minorversions[minorversion] = true; 158 break; 159 case NFSD_CLEAR: 160 nfsd_supported_minorversions[minorversion] = false; 161 break; 162 case NFSD_TEST: 163 return nfsd_supported_minorversions[minorversion]; 164 case NFSD_AVAIL: 165 return minorversion <= NFSD_SUPPORTED_MINOR_VERSION; 166 } 167 return 0; 168} 169 170/* 171 * Maximum number of nfsd processes 172 */ 173#define NFSD_MAXSERVS 8192 174 175int nfsd_nrthreads(struct net *net) 176{ 177 int rv = 0; 178 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 179 180 mutex_lock(&nfsd_mutex); 181 if (nn->nfsd_serv) 182 rv = nn->nfsd_serv->sv_nrthreads; 183 mutex_unlock(&nfsd_mutex); 184 return rv; 185} 186 187static int nfsd_init_socks(struct net *net) 188{ 189 int error; 190 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 191 192 if (!list_empty(&nn->nfsd_serv->sv_permsocks)) 193 return 0; 194 195 error = svc_create_xprt(nn->nfsd_serv, "udp", net, PF_INET, NFS_PORT, 196 SVC_SOCK_DEFAULTS); 197 if (error < 0) 198 return error; 199 200 error = svc_create_xprt(nn->nfsd_serv, "tcp", net, PF_INET, NFS_PORT, 201 SVC_SOCK_DEFAULTS); 202 if (error < 0) 203 return error; 204 205 return 0; 206} 207 208static int nfsd_users = 0; 209 210static int nfsd_startup_generic(int nrservs) 211{ 212 int ret; 213 214 if (nfsd_users++) 215 return 0; 216 217 /* 218 * Readahead param cache - will no-op if it already exists. 219 * (Note therefore results will be suboptimal if number of 220 * threads is modified after nfsd start.) 221 */ 222 ret = nfsd_racache_init(2*nrservs); 223 if (ret) 224 goto dec_users; 225 226 ret = nfs4_state_start(); 227 if (ret) 228 goto out_racache; 229 return 0; 230 231out_racache: 232 nfsd_racache_shutdown(); 233dec_users: 234 nfsd_users--; 235 return ret; 236} 237 238static void nfsd_shutdown_generic(void) 239{ 240 if (--nfsd_users) 241 return; 242 243 nfs4_state_shutdown(); 244 nfsd_racache_shutdown(); 245} 246 247static bool nfsd_needs_lockd(void) 248{ 249#if defined(CONFIG_NFSD_V3) 250 return (nfsd_versions[2] != NULL) || (nfsd_versions[3] != NULL); 251#else 252 return (nfsd_versions[2] != NULL); 253#endif 254} 255 256static int nfsd_startup_net(int nrservs, struct net *net) 257{ 258 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 259 int ret; 260 261 if (nn->nfsd_net_up) 262 return 0; 263 264 ret = nfsd_startup_generic(nrservs); 265 if (ret) 266 return ret; 267 ret = nfsd_init_socks(net); 268 if (ret) 269 goto out_socks; 270 271 if (nfsd_needs_lockd() && !nn->lockd_up) { 272 ret = lockd_up(net); 273 if (ret) 274 goto out_socks; 275 nn->lockd_up = 1; 276 } 277 278 ret = nfs4_state_start_net(net); 279 if (ret) 280 goto out_lockd; 281 282 nn->nfsd_net_up = true; 283 return 0; 284 285out_lockd: 286 if (nn->lockd_up) { 287 lockd_down(net); 288 nn->lockd_up = 0; 289 } 290out_socks: 291 nfsd_shutdown_generic(); 292 return ret; 293} 294 295static void nfsd_shutdown_net(struct net *net) 296{ 297 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 298 299 nfs4_state_shutdown_net(net); 300 if (nn->lockd_up) { 301 lockd_down(net); 302 nn->lockd_up = 0; 303 } 304 nn->nfsd_net_up = false; 305 nfsd_shutdown_generic(); 306} 307 308static void nfsd_last_thread(struct svc_serv *serv, struct net *net) 309{ 310 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 311 312 /* 313 * write_ports can create the server without actually starting 314 * any threads--if we get shut down before any threads are 315 * started, then nfsd_last_thread will be run before any of this 316 * other initialization has been done. 317 */ 318 if (!nn->nfsd_net_up) 319 return; 320 nfsd_shutdown_net(net); 321 322 svc_rpcb_cleanup(serv, net); 323 324 printk(KERN_WARNING "nfsd: last server has exited, flushing export " 325 "cache\n"); 326 nfsd_export_flush(net); 327} 328 329void nfsd_reset_versions(void) 330{ 331 int found_one = 0; 332 int i; 333 334 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) { 335 if (nfsd_program.pg_vers[i]) 336 found_one = 1; 337 } 338 339 if (!found_one) { 340 for (i = NFSD_MINVERS; i < NFSD_NRVERS; i++) 341 nfsd_program.pg_vers[i] = nfsd_version[i]; 342#if defined(CONFIG_NFSD_V2_ACL) || defined(CONFIG_NFSD_V3_ACL) 343 for (i = NFSD_ACL_MINVERS; i < NFSD_ACL_NRVERS; i++) 344 nfsd_acl_program.pg_vers[i] = 345 nfsd_acl_version[i]; 346#endif 347 } 348} 349 350/* 351 * Each session guarantees a negotiated per slot memory cache for replies 352 * which in turn consumes memory beyond the v2/v3/v4.0 server. A dedicated 353 * NFSv4.1 server might want to use more memory for a DRC than a machine 354 * with mutiple services. 355 * 356 * Impose a hard limit on the number of pages for the DRC which varies 357 * according to the machines free pages. This is of course only a default. 358 * 359 * For now this is a #defined shift which could be under admin control 360 * in the future. 361 */ 362static void set_max_drc(void) 363{ 364 #define NFSD_DRC_SIZE_SHIFT 10 365 nfsd_drc_max_mem = (nr_free_buffer_pages() 366 >> NFSD_DRC_SIZE_SHIFT) * PAGE_SIZE; 367 nfsd_drc_mem_used = 0; 368 spin_lock_init(&nfsd_drc_lock); 369 dprintk("%s nfsd_drc_max_mem %lu \n", __func__, nfsd_drc_max_mem); 370} 371 372static int nfsd_get_default_max_blksize(void) 373{ 374 struct sysinfo i; 375 unsigned long long target; 376 unsigned long ret; 377 378 si_meminfo(&i); 379 target = (i.totalram - i.totalhigh) << PAGE_SHIFT; 380 /* 381 * Aim for 1/4096 of memory per thread This gives 1MB on 4Gig 382 * machines, but only uses 32K on 128M machines. Bottom out at 383 * 8K on 32M and smaller. Of course, this is only a default. 384 */ 385 target >>= 12; 386 387 ret = NFSSVC_MAXBLKSIZE; 388 while (ret > target && ret >= 8*1024*2) 389 ret /= 2; 390 return ret; 391} 392 393int nfsd_create_serv(struct net *net) 394{ 395 int error; 396 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 397 398 WARN_ON(!mutex_is_locked(&nfsd_mutex)); 399 if (nn->nfsd_serv) { 400 svc_get(nn->nfsd_serv); 401 return 0; 402 } 403 if (nfsd_max_blksize == 0) 404 nfsd_max_blksize = nfsd_get_default_max_blksize(); 405 nfsd_reset_versions(); 406 nn->nfsd_serv = svc_create_pooled(&nfsd_program, nfsd_max_blksize, 407 nfsd_last_thread, nfsd, THIS_MODULE); 408 if (nn->nfsd_serv == NULL) 409 return -ENOMEM; 410 411 nn->nfsd_serv->sv_maxconn = nn->max_connections; 412 error = svc_bind(nn->nfsd_serv, net); 413 if (error < 0) { 414 svc_destroy(nn->nfsd_serv); 415 return error; 416 } 417 418 set_max_drc(); 419 do_gettimeofday(&nn->nfssvc_boot); /* record boot time */ 420 return 0; 421} 422 423int nfsd_nrpools(struct net *net) 424{ 425 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 426 427 if (nn->nfsd_serv == NULL) 428 return 0; 429 else 430 return nn->nfsd_serv->sv_nrpools; 431} 432 433int nfsd_get_nrthreads(int n, int *nthreads, struct net *net) 434{ 435 int i = 0; 436 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 437 438 if (nn->nfsd_serv != NULL) { 439 for (i = 0; i < nn->nfsd_serv->sv_nrpools && i < n; i++) 440 nthreads[i] = nn->nfsd_serv->sv_pools[i].sp_nrthreads; 441 } 442 443 return 0; 444} 445 446void nfsd_destroy(struct net *net) 447{ 448 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 449 int destroy = (nn->nfsd_serv->sv_nrthreads == 1); 450 451 if (destroy) 452 svc_shutdown_net(nn->nfsd_serv, net); 453 svc_destroy(nn->nfsd_serv); 454 if (destroy) 455 nn->nfsd_serv = NULL; 456} 457 458int nfsd_set_nrthreads(int n, int *nthreads, struct net *net) 459{ 460 int i = 0; 461 int tot = 0; 462 int err = 0; 463 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 464 465 WARN_ON(!mutex_is_locked(&nfsd_mutex)); 466 467 if (nn->nfsd_serv == NULL || n <= 0) 468 return 0; 469 470 if (n > nn->nfsd_serv->sv_nrpools) 471 n = nn->nfsd_serv->sv_nrpools; 472 473 /* enforce a global maximum number of threads */ 474 tot = 0; 475 for (i = 0; i < n; i++) { 476 nthreads[i] = min(nthreads[i], NFSD_MAXSERVS); 477 tot += nthreads[i]; 478 } 479 if (tot > NFSD_MAXSERVS) { 480 /* total too large: scale down requested numbers */ 481 for (i = 0; i < n && tot > 0; i++) { 482 int new = nthreads[i] * NFSD_MAXSERVS / tot; 483 tot -= (nthreads[i] - new); 484 nthreads[i] = new; 485 } 486 for (i = 0; i < n && tot > 0; i++) { 487 nthreads[i]--; 488 tot--; 489 } 490 } 491 492 /* 493 * There must always be a thread in pool 0; the admin 494 * can't shut down NFS completely using pool_threads. 495 */ 496 if (nthreads[0] == 0) 497 nthreads[0] = 1; 498 499 /* apply the new numbers */ 500 svc_get(nn->nfsd_serv); 501 for (i = 0; i < n; i++) { 502 err = svc_set_num_threads(nn->nfsd_serv, &nn->nfsd_serv->sv_pools[i], 503 nthreads[i]); 504 if (err) 505 break; 506 } 507 nfsd_destroy(net); 508 return err; 509} 510 511/* 512 * Adjust the number of threads and return the new number of threads. 513 * This is also the function that starts the server if necessary, if 514 * this is the first time nrservs is nonzero. 515 */ 516int 517nfsd_svc(int nrservs, struct net *net) 518{ 519 int error; 520 bool nfsd_up_before; 521 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 522 523 mutex_lock(&nfsd_mutex); 524 dprintk("nfsd: creating service\n"); 525 526 nrservs = max(nrservs, 0); 527 nrservs = min(nrservs, NFSD_MAXSERVS); 528 error = 0; 529 530 if (nrservs == 0 && nn->nfsd_serv == NULL) 531 goto out; 532 533 error = nfsd_create_serv(net); 534 if (error) 535 goto out; 536 537 nfsd_up_before = nn->nfsd_net_up; 538 539 error = nfsd_startup_net(nrservs, net); 540 if (error) 541 goto out_destroy; 542 error = svc_set_num_threads(nn->nfsd_serv, NULL, nrservs); 543 if (error) 544 goto out_shutdown; 545 /* We are holding a reference to nn->nfsd_serv which 546 * we don't want to count in the return value, 547 * so subtract 1 548 */ 549 error = nn->nfsd_serv->sv_nrthreads - 1; 550out_shutdown: 551 if (error < 0 && !nfsd_up_before) 552 nfsd_shutdown_net(net); 553out_destroy: 554 nfsd_destroy(net); /* Release server */ 555out: 556 mutex_unlock(&nfsd_mutex); 557 return error; 558} 559 560 561/* 562 * This is the NFS server kernel thread 563 */ 564static int 565nfsd(void *vrqstp) 566{ 567 struct svc_rqst *rqstp = (struct svc_rqst *) vrqstp; 568 struct svc_xprt *perm_sock = list_entry(rqstp->rq_server->sv_permsocks.next, typeof(struct svc_xprt), xpt_list); 569 struct net *net = perm_sock->xpt_net; 570 struct nfsd_net *nn = net_generic(net, nfsd_net_id); 571 int err; 572 573 /* Lock module and set up kernel thread */ 574 mutex_lock(&nfsd_mutex); 575 576 /* At this point, the thread shares current->fs 577 * with the init process. We need to create files with a 578 * umask of 0 instead of init's umask. */ 579 if (unshare_fs_struct() < 0) { 580 printk("Unable to start nfsd thread: out of memory\n"); 581 goto out; 582 } 583 584 current->fs->umask = 0; 585 586 /* 587 * thread is spawned with all signals set to SIG_IGN, re-enable 588 * the ones that will bring down the thread 589 */ 590 allow_signal(SIGKILL); 591 allow_signal(SIGHUP); 592 allow_signal(SIGINT); 593 allow_signal(SIGQUIT); 594 595 nfsdstats.th_cnt++; 596 mutex_unlock(&nfsd_mutex); 597 598 set_freezable(); 599 600 /* 601 * The main request loop 602 */ 603 for (;;) { 604 /* Update sv_maxconn if it has changed */ 605 rqstp->rq_server->sv_maxconn = nn->max_connections; 606 607 /* 608 * Find a socket with data available and call its 609 * recvfrom routine. 610 */ 611 while ((err = svc_recv(rqstp, 60*60*HZ)) == -EAGAIN) 612 ; 613 if (err == -EINTR) 614 break; 615 validate_process_creds(); 616 svc_process(rqstp); 617 validate_process_creds(); 618 } 619 620 /* Clear signals before calling svc_exit_thread() */ 621 flush_signals(current); 622 623 mutex_lock(&nfsd_mutex); 624 nfsdstats.th_cnt --; 625 626out: 627 rqstp->rq_server = NULL; 628 629 /* Release the thread */ 630 svc_exit_thread(rqstp); 631 632 nfsd_destroy(net); 633 634 /* Release module */ 635 mutex_unlock(&nfsd_mutex); 636 module_put_and_exit(0); 637 return 0; 638} 639 640static __be32 map_new_errors(u32 vers, __be32 nfserr) 641{ 642 if (nfserr == nfserr_jukebox && vers == 2) 643 return nfserr_dropit; 644 if (nfserr == nfserr_wrongsec && vers < 4) 645 return nfserr_acces; 646 return nfserr; 647} 648 649int 650nfsd_dispatch(struct svc_rqst *rqstp, __be32 *statp) 651{ 652 struct svc_procedure *proc; 653 kxdrproc_t xdr; 654 __be32 nfserr; 655 __be32 *nfserrp; 656 657 dprintk("nfsd_dispatch: vers %d proc %d\n", 658 rqstp->rq_vers, rqstp->rq_proc); 659 proc = rqstp->rq_procinfo; 660 661 /* 662 * Give the xdr decoder a chance to change this if it wants 663 * (necessary in the NFSv4.0 compound case) 664 */ 665 rqstp->rq_cachetype = proc->pc_cachetype; 666 /* Decode arguments */ 667 xdr = proc->pc_decode; 668 if (xdr && !xdr(rqstp, (__be32*)rqstp->rq_arg.head[0].iov_base, 669 rqstp->rq_argp)) { 670 dprintk("nfsd: failed to decode arguments!\n"); 671 *statp = rpc_garbage_args; 672 return 1; 673 } 674 675 /* Check whether we have this call in the cache. */ 676 switch (nfsd_cache_lookup(rqstp)) { 677 case RC_DROPIT: 678 return 0; 679 case RC_REPLY: 680 return 1; 681 case RC_DOIT:; 682 /* do it */ 683 } 684 685 /* need to grab the location to store the status, as 686 * nfsv4 does some encoding while processing 687 */ 688 nfserrp = rqstp->rq_res.head[0].iov_base 689 + rqstp->rq_res.head[0].iov_len; 690 rqstp->rq_res.head[0].iov_len += sizeof(__be32); 691 692 /* Now call the procedure handler, and encode NFS status. */ 693 nfserr = proc->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp); 694 nfserr = map_new_errors(rqstp->rq_vers, nfserr); 695 if (nfserr == nfserr_dropit || rqstp->rq_dropme) { 696 dprintk("nfsd: Dropping request; may be revisited later\n"); 697 nfsd_cache_update(rqstp, RC_NOCACHE, NULL); 698 return 0; 699 } 700 701 if (rqstp->rq_proc != 0) 702 *nfserrp++ = nfserr; 703 704 /* Encode result. 705 * For NFSv2, additional info is never returned in case of an error. 706 */ 707 if (!(nfserr && rqstp->rq_vers == 2)) { 708 xdr = proc->pc_encode; 709 if (xdr && !xdr(rqstp, nfserrp, 710 rqstp->rq_resp)) { 711 /* Failed to encode result. Release cache entry */ 712 dprintk("nfsd: failed to encode result!\n"); 713 nfsd_cache_update(rqstp, RC_NOCACHE, NULL); 714 *statp = rpc_system_err; 715 return 1; 716 } 717 } 718 719 /* Store reply in cache. */ 720 nfsd_cache_update(rqstp, rqstp->rq_cachetype, statp + 1); 721 return 1; 722} 723 724int nfsd_pool_stats_open(struct inode *inode, struct file *file) 725{ 726 int ret; 727 struct nfsd_net *nn = net_generic(inode->i_sb->s_fs_info, nfsd_net_id); 728 729 mutex_lock(&nfsd_mutex); 730 if (nn->nfsd_serv == NULL) { 731 mutex_unlock(&nfsd_mutex); 732 return -ENODEV; 733 } 734 /* bump up the psudo refcount while traversing */ 735 svc_get(nn->nfsd_serv); 736 ret = svc_pool_stats_open(nn->nfsd_serv, file); 737 mutex_unlock(&nfsd_mutex); 738 return ret; 739} 740 741int nfsd_pool_stats_release(struct inode *inode, struct file *file) 742{ 743 int ret = seq_release(inode, file); 744 struct net *net = inode->i_sb->s_fs_info; 745 746 mutex_lock(&nfsd_mutex); 747 /* this function really, really should have been called svc_put() */ 748 nfsd_destroy(net); 749 mutex_unlock(&nfsd_mutex); 750 return ret; 751} 752