1 // SPDX-License-Identifier: GPL-2.0-only 2 /* 3 * linux/fs/nfs/super.c 4 * 5 * Copyright (C) 1992 Rick Sladkey 6 * 7 * nfs superblock handling functions 8 * 9 * Modularised by Alan Cox <alan@lxorguk.ukuu.org.uk>, while hacking some 10 * experimental NFS changes. Modularisation taken straight from SYS5 fs. 11 * 12 * Change to nfs_read_super() to permit NFS mounts to multi-homed hosts. 13 * J.S.Peatfield@damtp.cam.ac.uk 14 * 15 * Split from inode.c by David Howells <dhowells@redhat.com> 16 * 17 * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a 18 * particular server are held in the same superblock 19 * - NFS superblocks can have several effective roots to the dentry tree 20 * - directory type roots are spliced into the tree when a path from one root reaches the root 21 * of another (see nfs_lookup()) 22 */ 23 24 #include <linux/module.h> 25 #include <linux/init.h> 26 27 #include <linux/time.h> 28 #include <linux/kernel.h> 29 #include <linux/mm.h> 30 #include <linux/string.h> 31 #include <linux/stat.h> 32 #include <linux/errno.h> 33 #include <linux/unistd.h> 34 #include <linux/sunrpc/clnt.h> 35 #include <linux/sunrpc/addr.h> 36 #include <linux/sunrpc/stats.h> 37 #include <linux/sunrpc/metrics.h> 38 #include <linux/sunrpc/xprtsock.h> 39 #include <linux/sunrpc/xprtrdma.h> 40 #include <linux/nfs_fs.h> 41 #include <linux/nfs_mount.h> 42 #include <linux/nfs4_mount.h> 43 #include <linux/lockd/bind.h> 44 #include <linux/seq_file.h> 45 #include <linux/mount.h> 46 #include <linux/namei.h> 47 #include <linux/vfs.h> 48 #include <linux/inet.h> 49 #include <linux/in6.h> 50 #include <linux/slab.h> 51 #include <net/ipv6.h> 52 #include <linux/netdevice.h> 53 #include <linux/nfs_xdr.h> 54 #include <linux/magic.h> 55 #include <linux/parser.h> 56 #include <linux/nsproxy.h> 57 #include <linux/rcupdate.h> 58 59 #include <linux/uaccess.h> 60 #include <linux/nfs_ssc.h> 61 62 #include "nfs4_fs.h" 63 #include "callback.h" 64 #include "delegation.h" 65 #include "iostat.h" 66 #include "internal.h" 67 #include "fscache.h" 68 #include "nfs4session.h" 69 #include "pnfs.h" 70 #include "nfs.h" 71 72 #define NFSDBG_FACILITY NFSDBG_VFS 73 74 const struct super_operations nfs_sops = { 75 .alloc_inode = nfs_alloc_inode, 76 .free_inode = nfs_free_inode, 77 .write_inode = nfs_write_inode, 78 .drop_inode = nfs_drop_inode, 79 .statfs = nfs_statfs, 80 .evict_inode = nfs_evict_inode, 81 .umount_begin = nfs_umount_begin, 82 .show_options = nfs_show_options, 83 .show_devname = nfs_show_devname, 84 .show_path = nfs_show_path, 85 .show_stats = nfs_show_stats, 86 }; 87 EXPORT_SYMBOL_GPL(nfs_sops); 88 89 #ifdef CONFIG_NFS_V4_2 90 static const struct nfs_ssc_client_ops nfs_ssc_clnt_ops_tbl = { 91 .sco_sb_deactive = nfs_sb_deactive, 92 }; 93 #endif 94 95 #if IS_ENABLED(CONFIG_NFS_V4) 96 static int __init register_nfs4_fs(void) 97 { 98 return register_filesystem(&nfs4_fs_type); 99 } 100 101 static void unregister_nfs4_fs(void) 102 { 103 unregister_filesystem(&nfs4_fs_type); 104 } 105 #else 106 static int __init register_nfs4_fs(void) 107 { 108 return 0; 109 } 110 111 static void unregister_nfs4_fs(void) 112 { 113 } 114 #endif 115 116 #ifdef CONFIG_NFS_V4_2 117 static void nfs_ssc_register_ops(void) 118 { 119 nfs_ssc_register(&nfs_ssc_clnt_ops_tbl); 120 } 121 122 static void nfs_ssc_unregister_ops(void) 123 { 124 nfs_ssc_unregister(&nfs_ssc_clnt_ops_tbl); 125 } 126 #endif /* CONFIG_NFS_V4_2 */ 127 128 static struct shrinker acl_shrinker = { 129 .count_objects = nfs_access_cache_count, 130 .scan_objects = nfs_access_cache_scan, 131 .seeks = DEFAULT_SEEKS, 132 }; 133 134 /* 135 * Register the NFS filesystems 136 */ 137 int __init register_nfs_fs(void) 138 { 139 int ret; 140 141 ret = register_filesystem(&nfs_fs_type); 142 if (ret < 0) 143 goto error_0; 144 145 ret = register_nfs4_fs(); 146 if (ret < 0) 147 goto error_1; 148 149 ret = nfs_register_sysctl(); 150 if (ret < 0) 151 goto error_2; 152 ret = register_shrinker(&acl_shrinker); 153 if (ret < 0) 154 goto error_3; 155 #ifdef CONFIG_NFS_V4_2 156 nfs_ssc_register_ops(); 157 #endif 158 return 0; 159 error_3: 160 nfs_unregister_sysctl(); 161 error_2: 162 unregister_nfs4_fs(); 163 error_1: 164 unregister_filesystem(&nfs_fs_type); 165 error_0: 166 return ret; 167 } 168 169 /* 170 * Unregister the NFS filesystems 171 */ 172 void __exit unregister_nfs_fs(void) 173 { 174 unregister_shrinker(&acl_shrinker); 175 nfs_unregister_sysctl(); 176 unregister_nfs4_fs(); 177 #ifdef CONFIG_NFS_V4_2 178 nfs_ssc_unregister_ops(); 179 #endif 180 unregister_filesystem(&nfs_fs_type); 181 } 182 183 bool nfs_sb_active(struct super_block *sb) 184 { 185 struct nfs_server *server = NFS_SB(sb); 186 187 if (!atomic_inc_not_zero(&sb->s_active)) 188 return false; 189 if (atomic_inc_return(&server->active) != 1) 190 atomic_dec(&sb->s_active); 191 return true; 192 } 193 EXPORT_SYMBOL_GPL(nfs_sb_active); 194 195 void nfs_sb_deactive(struct super_block *sb) 196 { 197 struct nfs_server *server = NFS_SB(sb); 198 199 if (atomic_dec_and_test(&server->active)) 200 deactivate_super(sb); 201 } 202 EXPORT_SYMBOL_GPL(nfs_sb_deactive); 203 204 static int __nfs_list_for_each_server(struct list_head *head, 205 int (*fn)(struct nfs_server *, void *), 206 void *data) 207 { 208 struct nfs_server *server, *last = NULL; 209 int ret = 0; 210 211 rcu_read_lock(); 212 list_for_each_entry_rcu(server, head, client_link) { 213 if (!(server->super && nfs_sb_active(server->super))) 214 continue; 215 rcu_read_unlock(); 216 if (last) 217 nfs_sb_deactive(last->super); 218 last = server; 219 ret = fn(server, data); 220 if (ret) 221 goto out; 222 rcu_read_lock(); 223 } 224 rcu_read_unlock(); 225 out: 226 if (last) 227 nfs_sb_deactive(last->super); 228 return ret; 229 } 230 231 int nfs_client_for_each_server(struct nfs_client *clp, 232 int (*fn)(struct nfs_server *, void *), 233 void *data) 234 { 235 return __nfs_list_for_each_server(&clp->cl_superblocks, fn, data); 236 } 237 EXPORT_SYMBOL_GPL(nfs_client_for_each_server); 238 239 /* 240 * Deliver file system statistics to userspace 241 */ 242 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf) 243 { 244 struct nfs_server *server = NFS_SB(dentry->d_sb); 245 unsigned char blockbits; 246 unsigned long blockres; 247 struct nfs_fh *fh = NFS_FH(d_inode(dentry)); 248 struct nfs_fsstat res; 249 int error = -ENOMEM; 250 251 res.fattr = nfs_alloc_fattr(); 252 if (res.fattr == NULL) 253 goto out_err; 254 255 error = server->nfs_client->rpc_ops->statfs(server, fh, &res); 256 if (unlikely(error == -ESTALE)) { 257 struct dentry *pd_dentry; 258 259 pd_dentry = dget_parent(dentry); 260 nfs_zap_caches(d_inode(pd_dentry)); 261 dput(pd_dentry); 262 } 263 nfs_free_fattr(res.fattr); 264 if (error < 0) 265 goto out_err; 266 267 buf->f_type = NFS_SUPER_MAGIC; 268 269 /* 270 * Current versions of glibc do not correctly handle the 271 * case where f_frsize != f_bsize. Eventually we want to 272 * report the value of wtmult in this field. 273 */ 274 buf->f_frsize = dentry->d_sb->s_blocksize; 275 276 /* 277 * On most *nix systems, f_blocks, f_bfree, and f_bavail 278 * are reported in units of f_frsize. Linux hasn't had 279 * an f_frsize field in its statfs struct until recently, 280 * thus historically Linux's sys_statfs reports these 281 * fields in units of f_bsize. 282 */ 283 buf->f_bsize = dentry->d_sb->s_blocksize; 284 blockbits = dentry->d_sb->s_blocksize_bits; 285 blockres = (1 << blockbits) - 1; 286 buf->f_blocks = (res.tbytes + blockres) >> blockbits; 287 buf->f_bfree = (res.fbytes + blockres) >> blockbits; 288 buf->f_bavail = (res.abytes + blockres) >> blockbits; 289 290 buf->f_files = res.tfiles; 291 buf->f_ffree = res.afiles; 292 293 buf->f_namelen = server->namelen; 294 295 return 0; 296 297 out_err: 298 dprintk("%s: statfs error = %d\n", __func__, -error); 299 return error; 300 } 301 EXPORT_SYMBOL_GPL(nfs_statfs); 302 303 /* 304 * Map the security flavour number to a name 305 */ 306 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour) 307 { 308 static const struct { 309 rpc_authflavor_t flavour; 310 const char *str; 311 } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = { 312 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */ 313 { RPC_AUTH_NULL, "null" }, 314 { RPC_AUTH_UNIX, "sys" }, 315 { RPC_AUTH_GSS_KRB5, "krb5" }, 316 { RPC_AUTH_GSS_KRB5I, "krb5i" }, 317 { RPC_AUTH_GSS_KRB5P, "krb5p" }, 318 { RPC_AUTH_GSS_LKEY, "lkey" }, 319 { RPC_AUTH_GSS_LKEYI, "lkeyi" }, 320 { RPC_AUTH_GSS_LKEYP, "lkeyp" }, 321 { RPC_AUTH_GSS_SPKM, "spkm" }, 322 { RPC_AUTH_GSS_SPKMI, "spkmi" }, 323 { RPC_AUTH_GSS_SPKMP, "spkmp" }, 324 { UINT_MAX, "unknown" } 325 }; 326 int i; 327 328 for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) { 329 if (sec_flavours[i].flavour == flavour) 330 break; 331 } 332 return sec_flavours[i].str; 333 } 334 335 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss, 336 int showdefaults) 337 { 338 struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address; 339 char *proto = NULL; 340 341 switch (sap->sa_family) { 342 case AF_INET: 343 switch (nfss->mountd_protocol) { 344 case IPPROTO_UDP: 345 proto = RPCBIND_NETID_UDP; 346 break; 347 case IPPROTO_TCP: 348 proto = RPCBIND_NETID_TCP; 349 break; 350 } 351 break; 352 case AF_INET6: 353 switch (nfss->mountd_protocol) { 354 case IPPROTO_UDP: 355 proto = RPCBIND_NETID_UDP6; 356 break; 357 case IPPROTO_TCP: 358 proto = RPCBIND_NETID_TCP6; 359 break; 360 } 361 break; 362 } 363 if (proto || showdefaults) 364 seq_printf(m, ",mountproto=%s", proto ?: "auto"); 365 } 366 367 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss, 368 int showdefaults) 369 { 370 struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address; 371 372 if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE) 373 return; 374 375 switch (sap->sa_family) { 376 case AF_INET: { 377 struct sockaddr_in *sin = (struct sockaddr_in *)sap; 378 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr); 379 break; 380 } 381 case AF_INET6: { 382 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap; 383 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr); 384 break; 385 } 386 default: 387 if (showdefaults) 388 seq_puts(m, ",mountaddr=unspecified"); 389 } 390 391 if (nfss->mountd_version || showdefaults) 392 seq_printf(m, ",mountvers=%u", nfss->mountd_version); 393 if ((nfss->mountd_port && 394 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) || 395 showdefaults) 396 seq_printf(m, ",mountport=%u", nfss->mountd_port); 397 398 nfs_show_mountd_netid(m, nfss, showdefaults); 399 } 400 401 #if IS_ENABLED(CONFIG_NFS_V4) 402 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss, 403 int showdefaults) 404 { 405 struct nfs_client *clp = nfss->nfs_client; 406 407 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr); 408 } 409 #else 410 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss, 411 int showdefaults) 412 { 413 } 414 #endif 415 416 static void nfs_show_nfs_version(struct seq_file *m, 417 unsigned int version, 418 unsigned int minorversion) 419 { 420 seq_printf(m, ",vers=%u", version); 421 if (version == 4) 422 seq_printf(m, ".%u", minorversion); 423 } 424 425 /* 426 * Describe the mount options in force on this server representation 427 */ 428 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, 429 int showdefaults) 430 { 431 static const struct proc_nfs_info { 432 int flag; 433 const char *str; 434 const char *nostr; 435 } nfs_info[] = { 436 { NFS_MOUNT_SOFT, ",soft", "" }, 437 { NFS_MOUNT_SOFTERR, ",softerr", "" }, 438 { NFS_MOUNT_SOFTREVAL, ",softreval", "" }, 439 { NFS_MOUNT_POSIX, ",posix", "" }, 440 { NFS_MOUNT_NOCTO, ",nocto", "" }, 441 { NFS_MOUNT_NOAC, ",noac", "" }, 442 { NFS_MOUNT_NONLM, ",nolock", "" }, 443 { NFS_MOUNT_NOACL, ",noacl", "" }, 444 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" }, 445 { NFS_MOUNT_UNSHARED, ",nosharecache", "" }, 446 { NFS_MOUNT_NORESVPORT, ",noresvport", "" }, 447 { 0, NULL, NULL } 448 }; 449 const struct proc_nfs_info *nfs_infop; 450 struct nfs_client *clp = nfss->nfs_client; 451 u32 version = clp->rpc_ops->version; 452 int local_flock, local_fcntl; 453 454 nfs_show_nfs_version(m, version, clp->cl_minorversion); 455 seq_printf(m, ",rsize=%u", nfss->rsize); 456 seq_printf(m, ",wsize=%u", nfss->wsize); 457 if (nfss->bsize != 0) 458 seq_printf(m, ",bsize=%u", nfss->bsize); 459 seq_printf(m, ",namlen=%u", nfss->namelen); 460 if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults) 461 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ); 462 if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults) 463 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ); 464 if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults) 465 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ); 466 if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults) 467 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ); 468 if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))) 469 seq_puts(m, ",hard"); 470 for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) { 471 if (nfss->flags & nfs_infop->flag) 472 seq_puts(m, nfs_infop->str); 473 else 474 seq_puts(m, nfs_infop->nostr); 475 } 476 rcu_read_lock(); 477 seq_printf(m, ",proto=%s", 478 rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID)); 479 rcu_read_unlock(); 480 if (clp->cl_nconnect > 0) 481 seq_printf(m, ",nconnect=%u", clp->cl_nconnect); 482 if (version == 4) { 483 if (clp->cl_max_connect > 1) 484 seq_printf(m, ",max_connect=%u", clp->cl_max_connect); 485 if (nfss->port != NFS_PORT) 486 seq_printf(m, ",port=%u", nfss->port); 487 } else 488 if (nfss->port) 489 seq_printf(m, ",port=%u", nfss->port); 490 491 seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ); 492 seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries); 493 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor)); 494 495 if (version != 4) 496 nfs_show_mountd_options(m, nfss, showdefaults); 497 else 498 nfs_show_nfsv4_options(m, nfss, showdefaults); 499 500 if (nfss->options & NFS_OPTION_FSCACHE) 501 seq_puts(m, ",fsc"); 502 503 if (nfss->options & NFS_OPTION_MIGRATION) 504 seq_puts(m, ",migration"); 505 506 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) { 507 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE) 508 seq_puts(m, ",lookupcache=none"); 509 else 510 seq_puts(m, ",lookupcache=pos"); 511 } 512 513 local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK; 514 local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL; 515 516 if (!local_flock && !local_fcntl) 517 seq_puts(m, ",local_lock=none"); 518 else if (local_flock && local_fcntl) 519 seq_puts(m, ",local_lock=all"); 520 else if (local_flock) 521 seq_puts(m, ",local_lock=flock"); 522 else 523 seq_puts(m, ",local_lock=posix"); 524 525 if (nfss->flags & NFS_MOUNT_WRITE_EAGER) { 526 if (nfss->flags & NFS_MOUNT_WRITE_WAIT) 527 seq_puts(m, ",write=wait"); 528 else 529 seq_puts(m, ",write=eager"); 530 } 531 } 532 533 /* 534 * Describe the mount options on this VFS mountpoint 535 */ 536 int nfs_show_options(struct seq_file *m, struct dentry *root) 537 { 538 struct nfs_server *nfss = NFS_SB(root->d_sb); 539 540 nfs_show_mount_options(m, nfss, 0); 541 542 rcu_read_lock(); 543 seq_printf(m, ",addr=%s", 544 rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient, 545 RPC_DISPLAY_ADDR)); 546 rcu_read_unlock(); 547 548 return 0; 549 } 550 EXPORT_SYMBOL_GPL(nfs_show_options); 551 552 #if IS_ENABLED(CONFIG_NFS_V4) 553 static void show_lease(struct seq_file *m, struct nfs_server *server) 554 { 555 struct nfs_client *clp = server->nfs_client; 556 unsigned long expire; 557 558 seq_printf(m, ",lease_time=%ld", clp->cl_lease_time / HZ); 559 expire = clp->cl_last_renewal + clp->cl_lease_time; 560 seq_printf(m, ",lease_expired=%ld", 561 time_after(expire, jiffies) ? 0 : (jiffies - expire) / HZ); 562 } 563 #ifdef CONFIG_NFS_V4_1 564 static void show_sessions(struct seq_file *m, struct nfs_server *server) 565 { 566 if (nfs4_has_session(server->nfs_client)) 567 seq_puts(m, ",sessions"); 568 } 569 #else 570 static void show_sessions(struct seq_file *m, struct nfs_server *server) {} 571 #endif 572 #endif 573 574 #ifdef CONFIG_NFS_V4_1 575 static void show_pnfs(struct seq_file *m, struct nfs_server *server) 576 { 577 seq_printf(m, ",pnfs="); 578 if (server->pnfs_curr_ld) 579 seq_printf(m, "%s", server->pnfs_curr_ld->name); 580 else 581 seq_printf(m, "not configured"); 582 } 583 584 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss) 585 { 586 if (nfss->nfs_client && nfss->nfs_client->cl_implid) { 587 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid; 588 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s'," 589 "date='%llu,%u'", 590 impl_id->name, impl_id->domain, 591 impl_id->date.seconds, impl_id->date.nseconds); 592 } 593 } 594 #else 595 #if IS_ENABLED(CONFIG_NFS_V4) 596 static void show_pnfs(struct seq_file *m, struct nfs_server *server) 597 { 598 } 599 #endif 600 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss) 601 { 602 } 603 #endif 604 605 int nfs_show_devname(struct seq_file *m, struct dentry *root) 606 { 607 char *page = (char *) __get_free_page(GFP_KERNEL); 608 char *devname, *dummy; 609 int err = 0; 610 if (!page) 611 return -ENOMEM; 612 devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0); 613 if (IS_ERR(devname)) 614 err = PTR_ERR(devname); 615 else 616 seq_escape(m, devname, " \t\n\\"); 617 free_page((unsigned long)page); 618 return err; 619 } 620 EXPORT_SYMBOL_GPL(nfs_show_devname); 621 622 int nfs_show_path(struct seq_file *m, struct dentry *dentry) 623 { 624 seq_puts(m, "/"); 625 return 0; 626 } 627 EXPORT_SYMBOL_GPL(nfs_show_path); 628 629 /* 630 * Present statistical information for this VFS mountpoint 631 */ 632 int nfs_show_stats(struct seq_file *m, struct dentry *root) 633 { 634 int i, cpu; 635 struct nfs_server *nfss = NFS_SB(root->d_sb); 636 struct rpc_auth *auth = nfss->client->cl_auth; 637 struct nfs_iostats totals = { }; 638 639 seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS); 640 641 /* 642 * Display all mount option settings 643 */ 644 seq_puts(m, "\n\topts:\t"); 645 seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw"); 646 seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : ""); 647 seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : ""); 648 seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : ""); 649 nfs_show_mount_options(m, nfss, 1); 650 651 seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ); 652 653 show_implementation_id(m, nfss); 654 655 seq_puts(m, "\n\tcaps:\t"); 656 seq_printf(m, "caps=0x%x", nfss->caps); 657 seq_printf(m, ",wtmult=%u", nfss->wtmult); 658 seq_printf(m, ",dtsize=%u", nfss->dtsize); 659 seq_printf(m, ",bsize=%u", nfss->bsize); 660 seq_printf(m, ",namlen=%u", nfss->namelen); 661 662 #if IS_ENABLED(CONFIG_NFS_V4) 663 if (nfss->nfs_client->rpc_ops->version == 4) { 664 seq_puts(m, "\n\tnfsv4:\t"); 665 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]); 666 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]); 667 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]); 668 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask); 669 show_sessions(m, nfss); 670 show_pnfs(m, nfss); 671 show_lease(m, nfss); 672 } 673 #endif 674 675 /* 676 * Display security flavor in effect for this mount 677 */ 678 seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor); 679 if (auth->au_flavor) 680 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor); 681 682 /* 683 * Display superblock I/O counters 684 */ 685 for_each_possible_cpu(cpu) { 686 struct nfs_iostats *stats; 687 688 preempt_disable(); 689 stats = per_cpu_ptr(nfss->io_stats, cpu); 690 691 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 692 totals.events[i] += stats->events[i]; 693 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 694 totals.bytes[i] += stats->bytes[i]; 695 #ifdef CONFIG_NFS_FSCACHE 696 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++) 697 totals.fscache[i] += stats->fscache[i]; 698 #endif 699 700 preempt_enable(); 701 } 702 703 seq_puts(m, "\n\tevents:\t"); 704 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 705 seq_printf(m, "%lu ", totals.events[i]); 706 seq_puts(m, "\n\tbytes:\t"); 707 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 708 seq_printf(m, "%Lu ", totals.bytes[i]); 709 #ifdef CONFIG_NFS_FSCACHE 710 if (nfss->options & NFS_OPTION_FSCACHE) { 711 seq_puts(m, "\n\tfsc:\t"); 712 for (i = 0; i < __NFSIOS_FSCACHEMAX; i++) 713 seq_printf(m, "%Lu ", totals.fscache[i]); 714 } 715 #endif 716 seq_putc(m, '\n'); 717 718 rpc_clnt_show_stats(m, nfss->client); 719 720 return 0; 721 } 722 EXPORT_SYMBOL_GPL(nfs_show_stats); 723 724 /* 725 * Begin unmount by attempting to remove all automounted mountpoints we added 726 * in response to xdev traversals and referrals 727 */ 728 void nfs_umount_begin(struct super_block *sb) 729 { 730 struct nfs_server *server; 731 struct rpc_clnt *rpc; 732 733 server = NFS_SB(sb); 734 /* -EIO all pending I/O */ 735 rpc = server->client_acl; 736 if (!IS_ERR(rpc)) 737 rpc_killall_tasks(rpc); 738 rpc = server->client; 739 if (!IS_ERR(rpc)) 740 rpc_killall_tasks(rpc); 741 } 742 EXPORT_SYMBOL_GPL(nfs_umount_begin); 743 744 /* 745 * Return true if 'match' is in auth_info or auth_info is empty. 746 * Return false otherwise. 747 */ 748 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info, 749 rpc_authflavor_t match) 750 { 751 int i; 752 753 if (!auth_info->flavor_len) 754 return true; 755 756 for (i = 0; i < auth_info->flavor_len; i++) { 757 if (auth_info->flavors[i] == match) 758 return true; 759 } 760 return false; 761 } 762 EXPORT_SYMBOL_GPL(nfs_auth_info_match); 763 764 /* 765 * Ensure that a specified authtype in ctx->auth_info is supported by 766 * the server. Returns 0 and sets ctx->selected_flavor if it's ok, and 767 * -EACCES if not. 768 */ 769 static int nfs_verify_authflavors(struct nfs_fs_context *ctx, 770 rpc_authflavor_t *server_authlist, 771 unsigned int count) 772 { 773 rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR; 774 bool found_auth_null = false; 775 unsigned int i; 776 777 /* 778 * If the sec= mount option is used, the specified flavor or AUTH_NULL 779 * must be in the list returned by the server. 780 * 781 * AUTH_NULL has a special meaning when it's in the server list - it 782 * means that the server will ignore the rpc creds, so any flavor 783 * can be used but still use the sec= that was specified. 784 * 785 * Note also that the MNT procedure in MNTv1 does not return a list 786 * of supported security flavors. In this case, nfs_mount() fabricates 787 * a security flavor list containing just AUTH_NULL. 788 */ 789 for (i = 0; i < count; i++) { 790 flavor = server_authlist[i]; 791 792 if (nfs_auth_info_match(&ctx->auth_info, flavor)) 793 goto out; 794 795 if (flavor == RPC_AUTH_NULL) 796 found_auth_null = true; 797 } 798 799 if (found_auth_null) { 800 flavor = ctx->auth_info.flavors[0]; 801 goto out; 802 } 803 804 dfprintk(MOUNT, 805 "NFS: specified auth flavors not supported by server\n"); 806 return -EACCES; 807 808 out: 809 ctx->selected_flavor = flavor; 810 dfprintk(MOUNT, "NFS: using auth flavor %u\n", ctx->selected_flavor); 811 return 0; 812 } 813 814 /* 815 * Use the remote server's MOUNT service to request the NFS file handle 816 * corresponding to the provided path. 817 */ 818 static int nfs_request_mount(struct fs_context *fc, 819 struct nfs_fh *root_fh, 820 rpc_authflavor_t *server_authlist, 821 unsigned int *server_authlist_len) 822 { 823 struct nfs_fs_context *ctx = nfs_fc2context(fc); 824 struct nfs_mount_request request = { 825 .sap = (struct sockaddr *) 826 &ctx->mount_server.address, 827 .dirpath = ctx->nfs_server.export_path, 828 .protocol = ctx->mount_server.protocol, 829 .fh = root_fh, 830 .noresvport = ctx->flags & NFS_MOUNT_NORESVPORT, 831 .auth_flav_len = server_authlist_len, 832 .auth_flavs = server_authlist, 833 .net = fc->net_ns, 834 }; 835 int status; 836 837 if (ctx->mount_server.version == 0) { 838 switch (ctx->version) { 839 default: 840 ctx->mount_server.version = NFS_MNT3_VERSION; 841 break; 842 case 2: 843 ctx->mount_server.version = NFS_MNT_VERSION; 844 } 845 } 846 request.version = ctx->mount_server.version; 847 848 if (ctx->mount_server.hostname) 849 request.hostname = ctx->mount_server.hostname; 850 else 851 request.hostname = ctx->nfs_server.hostname; 852 853 /* 854 * Construct the mount server's address. 855 */ 856 if (ctx->mount_server.address.sa_family == AF_UNSPEC) { 857 memcpy(request.sap, &ctx->nfs_server.address, 858 ctx->nfs_server.addrlen); 859 ctx->mount_server.addrlen = ctx->nfs_server.addrlen; 860 } 861 request.salen = ctx->mount_server.addrlen; 862 nfs_set_port(request.sap, &ctx->mount_server.port, 0); 863 864 /* 865 * Now ask the mount server to map our export path 866 * to a file handle. 867 */ 868 status = nfs_mount(&request, ctx->timeo, ctx->retrans); 869 if (status != 0) { 870 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n", 871 request.hostname, status); 872 return status; 873 } 874 875 return 0; 876 } 877 878 static struct nfs_server *nfs_try_mount_request(struct fs_context *fc) 879 { 880 struct nfs_fs_context *ctx = nfs_fc2context(fc); 881 int status; 882 unsigned int i; 883 bool tried_auth_unix = false; 884 bool auth_null_in_list = false; 885 struct nfs_server *server = ERR_PTR(-EACCES); 886 rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS]; 887 unsigned int authlist_len = ARRAY_SIZE(authlist); 888 889 status = nfs_request_mount(fc, ctx->mntfh, authlist, &authlist_len); 890 if (status) 891 return ERR_PTR(status); 892 893 /* 894 * Was a sec= authflavor specified in the options? First, verify 895 * whether the server supports it, and then just try to use it if so. 896 */ 897 if (ctx->auth_info.flavor_len > 0) { 898 status = nfs_verify_authflavors(ctx, authlist, authlist_len); 899 dfprintk(MOUNT, "NFS: using auth flavor %u\n", 900 ctx->selected_flavor); 901 if (status) 902 return ERR_PTR(status); 903 return ctx->nfs_mod->rpc_ops->create_server(fc); 904 } 905 906 /* 907 * No sec= option was provided. RFC 2623, section 2.7 suggests we 908 * SHOULD prefer the flavor listed first. However, some servers list 909 * AUTH_NULL first. Avoid ever choosing AUTH_NULL. 910 */ 911 for (i = 0; i < authlist_len; ++i) { 912 rpc_authflavor_t flavor; 913 struct rpcsec_gss_info info; 914 915 flavor = authlist[i]; 916 switch (flavor) { 917 case RPC_AUTH_UNIX: 918 tried_auth_unix = true; 919 break; 920 case RPC_AUTH_NULL: 921 auth_null_in_list = true; 922 continue; 923 default: 924 if (rpcauth_get_gssinfo(flavor, &info) != 0) 925 continue; 926 break; 927 } 928 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor); 929 ctx->selected_flavor = flavor; 930 server = ctx->nfs_mod->rpc_ops->create_server(fc); 931 if (!IS_ERR(server)) 932 return server; 933 } 934 935 /* 936 * Nothing we tried so far worked. At this point, give up if we've 937 * already tried AUTH_UNIX or if the server's list doesn't contain 938 * AUTH_NULL 939 */ 940 if (tried_auth_unix || !auth_null_in_list) 941 return server; 942 943 /* Last chance! Try AUTH_UNIX */ 944 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX); 945 ctx->selected_flavor = RPC_AUTH_UNIX; 946 return ctx->nfs_mod->rpc_ops->create_server(fc); 947 } 948 949 int nfs_try_get_tree(struct fs_context *fc) 950 { 951 struct nfs_fs_context *ctx = nfs_fc2context(fc); 952 953 if (ctx->need_mount) 954 ctx->server = nfs_try_mount_request(fc); 955 else 956 ctx->server = ctx->nfs_mod->rpc_ops->create_server(fc); 957 958 return nfs_get_tree_common(fc); 959 } 960 EXPORT_SYMBOL_GPL(nfs_try_get_tree); 961 962 963 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \ 964 | NFS_MOUNT_SECURE \ 965 | NFS_MOUNT_TCP \ 966 | NFS_MOUNT_VER3 \ 967 | NFS_MOUNT_KERBEROS \ 968 | NFS_MOUNT_NONLM \ 969 | NFS_MOUNT_BROKEN_SUID \ 970 | NFS_MOUNT_STRICTLOCK \ 971 | NFS_MOUNT_LEGACY_INTERFACE) 972 973 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \ 974 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT)) 975 976 static int 977 nfs_compare_remount_data(struct nfs_server *nfss, 978 struct nfs_fs_context *ctx) 979 { 980 if ((ctx->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK || 981 ctx->rsize != nfss->rsize || 982 ctx->wsize != nfss->wsize || 983 ctx->version != nfss->nfs_client->rpc_ops->version || 984 ctx->minorversion != nfss->nfs_client->cl_minorversion || 985 ctx->retrans != nfss->client->cl_timeout->to_retries || 986 !nfs_auth_info_match(&ctx->auth_info, nfss->client->cl_auth->au_flavor) || 987 ctx->acregmin != nfss->acregmin / HZ || 988 ctx->acregmax != nfss->acregmax / HZ || 989 ctx->acdirmin != nfss->acdirmin / HZ || 990 ctx->acdirmax != nfss->acdirmax / HZ || 991 ctx->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) || 992 (ctx->options & NFS_OPTION_FSCACHE) != (nfss->options & NFS_OPTION_FSCACHE) || 993 ctx->nfs_server.port != nfss->port || 994 ctx->nfs_server.addrlen != nfss->nfs_client->cl_addrlen || 995 !rpc_cmp_addr((struct sockaddr *)&ctx->nfs_server.address, 996 (struct sockaddr *)&nfss->nfs_client->cl_addr)) 997 return -EINVAL; 998 999 return 0; 1000 } 1001 1002 int nfs_reconfigure(struct fs_context *fc) 1003 { 1004 struct nfs_fs_context *ctx = nfs_fc2context(fc); 1005 struct super_block *sb = fc->root->d_sb; 1006 struct nfs_server *nfss = sb->s_fs_info; 1007 int ret; 1008 1009 sync_filesystem(sb); 1010 1011 /* 1012 * Userspace mount programs that send binary options generally send 1013 * them populated with default values. We have no way to know which 1014 * ones were explicitly specified. Fall back to legacy behavior and 1015 * just return success. 1016 */ 1017 if (ctx->skip_reconfig_option_check) 1018 return 0; 1019 1020 /* 1021 * noac is a special case. It implies -o sync, but that's not 1022 * necessarily reflected in the mtab options. reconfigure_super 1023 * will clear SB_SYNCHRONOUS if -o sync wasn't specified in the 1024 * remount options, so we have to explicitly reset it. 1025 */ 1026 if (ctx->flags & NFS_MOUNT_NOAC) { 1027 fc->sb_flags |= SB_SYNCHRONOUS; 1028 fc->sb_flags_mask |= SB_SYNCHRONOUS; 1029 } 1030 1031 /* compare new mount options with old ones */ 1032 ret = nfs_compare_remount_data(nfss, ctx); 1033 if (ret) 1034 return ret; 1035 1036 return nfs_probe_server(nfss, NFS_FH(d_inode(fc->root))); 1037 } 1038 EXPORT_SYMBOL_GPL(nfs_reconfigure); 1039 1040 /* 1041 * Finish setting up an NFS superblock 1042 */ 1043 static void nfs_fill_super(struct super_block *sb, struct nfs_fs_context *ctx) 1044 { 1045 struct nfs_server *server = NFS_SB(sb); 1046 1047 sb->s_blocksize_bits = 0; 1048 sb->s_blocksize = 0; 1049 sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr; 1050 sb->s_op = server->nfs_client->cl_nfs_mod->sops; 1051 if (ctx->bsize) 1052 sb->s_blocksize = nfs_block_size(ctx->bsize, &sb->s_blocksize_bits); 1053 1054 if (server->nfs_client->rpc_ops->version != 2) { 1055 /* The VFS shouldn't apply the umask to mode bits. We will do 1056 * so ourselves when necessary. 1057 */ 1058 sb->s_flags |= SB_POSIXACL; 1059 sb->s_time_gran = 1; 1060 sb->s_export_op = &nfs_export_ops; 1061 } else 1062 sb->s_time_gran = 1000; 1063 1064 if (server->nfs_client->rpc_ops->version != 4) { 1065 sb->s_time_min = 0; 1066 sb->s_time_max = U32_MAX; 1067 } else { 1068 sb->s_time_min = S64_MIN; 1069 sb->s_time_max = S64_MAX; 1070 } 1071 1072 sb->s_magic = NFS_SUPER_MAGIC; 1073 1074 /* We probably want something more informative here */ 1075 snprintf(sb->s_id, sizeof(sb->s_id), 1076 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev)); 1077 1078 if (sb->s_blocksize == 0) 1079 sb->s_blocksize = nfs_block_bits(server->wsize, 1080 &sb->s_blocksize_bits); 1081 1082 nfs_super_set_maxbytes(sb, server->maxfilesize); 1083 server->has_sec_mnt_opts = ctx->has_sec_mnt_opts; 1084 } 1085 1086 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, 1087 const struct fs_context *fc) 1088 { 1089 const struct nfs_server *a = s->s_fs_info; 1090 const struct rpc_clnt *clnt_a = a->client; 1091 const struct rpc_clnt *clnt_b = b->client; 1092 1093 if ((s->s_flags & NFS_SB_MASK) != (fc->sb_flags & NFS_SB_MASK)) 1094 goto Ebusy; 1095 if (a->nfs_client != b->nfs_client) 1096 goto Ebusy; 1097 if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK) 1098 goto Ebusy; 1099 if (a->wsize != b->wsize) 1100 goto Ebusy; 1101 if (a->rsize != b->rsize) 1102 goto Ebusy; 1103 if (a->acregmin != b->acregmin) 1104 goto Ebusy; 1105 if (a->acregmax != b->acregmax) 1106 goto Ebusy; 1107 if (a->acdirmin != b->acdirmin) 1108 goto Ebusy; 1109 if (a->acdirmax != b->acdirmax) 1110 goto Ebusy; 1111 if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor) 1112 goto Ebusy; 1113 return 1; 1114 Ebusy: 1115 return 0; 1116 } 1117 1118 static int nfs_set_super(struct super_block *s, struct fs_context *fc) 1119 { 1120 struct nfs_server *server = fc->s_fs_info; 1121 int ret; 1122 1123 s->s_d_op = server->nfs_client->rpc_ops->dentry_ops; 1124 ret = set_anon_super(s, server); 1125 if (ret == 0) 1126 server->s_dev = s->s_dev; 1127 return ret; 1128 } 1129 1130 static int nfs_compare_super_address(struct nfs_server *server1, 1131 struct nfs_server *server2) 1132 { 1133 struct sockaddr *sap1, *sap2; 1134 struct rpc_xprt *xprt1 = server1->client->cl_xprt; 1135 struct rpc_xprt *xprt2 = server2->client->cl_xprt; 1136 1137 if (!net_eq(xprt1->xprt_net, xprt2->xprt_net)) 1138 return 0; 1139 1140 sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr; 1141 sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr; 1142 1143 if (sap1->sa_family != sap2->sa_family) 1144 return 0; 1145 1146 switch (sap1->sa_family) { 1147 case AF_INET: { 1148 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1; 1149 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2; 1150 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr) 1151 return 0; 1152 if (sin1->sin_port != sin2->sin_port) 1153 return 0; 1154 break; 1155 } 1156 case AF_INET6: { 1157 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1; 1158 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2; 1159 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr)) 1160 return 0; 1161 if (sin1->sin6_port != sin2->sin6_port) 1162 return 0; 1163 break; 1164 } 1165 default: 1166 return 0; 1167 } 1168 1169 return 1; 1170 } 1171 1172 static int nfs_compare_userns(const struct nfs_server *old, 1173 const struct nfs_server *new) 1174 { 1175 const struct user_namespace *oldns = &init_user_ns; 1176 const struct user_namespace *newns = &init_user_ns; 1177 1178 if (old->client && old->client->cl_cred) 1179 oldns = old->client->cl_cred->user_ns; 1180 if (new->client && new->client->cl_cred) 1181 newns = new->client->cl_cred->user_ns; 1182 if (oldns != newns) 1183 return 0; 1184 return 1; 1185 } 1186 1187 static int nfs_compare_super(struct super_block *sb, struct fs_context *fc) 1188 { 1189 struct nfs_server *server = fc->s_fs_info, *old = NFS_SB(sb); 1190 1191 if (!nfs_compare_super_address(old, server)) 1192 return 0; 1193 /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */ 1194 if (old->flags & NFS_MOUNT_UNSHARED) 1195 return 0; 1196 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0) 1197 return 0; 1198 if (!nfs_compare_userns(old, server)) 1199 return 0; 1200 if ((old->has_sec_mnt_opts || fc->security) && 1201 security_sb_mnt_opts_compat(sb, fc->security)) 1202 return 0; 1203 return nfs_compare_mount_options(sb, server, fc); 1204 } 1205 1206 #ifdef CONFIG_NFS_FSCACHE 1207 static int nfs_get_cache_cookie(struct super_block *sb, 1208 struct nfs_fs_context *ctx) 1209 { 1210 struct nfs_server *nfss = NFS_SB(sb); 1211 char *uniq = NULL; 1212 int ulen = 0; 1213 1214 nfss->fscache = NULL; 1215 1216 if (!ctx) 1217 return 0; 1218 1219 if (ctx->clone_data.sb) { 1220 struct nfs_server *mnt_s = NFS_SB(ctx->clone_data.sb); 1221 if (!(mnt_s->options & NFS_OPTION_FSCACHE)) 1222 return 0; 1223 if (mnt_s->fscache_uniq) { 1224 uniq = mnt_s->fscache_uniq; 1225 ulen = strlen(uniq); 1226 } 1227 } else { 1228 if (!(ctx->options & NFS_OPTION_FSCACHE)) 1229 return 0; 1230 if (ctx->fscache_uniq) { 1231 uniq = ctx->fscache_uniq; 1232 ulen = strlen(ctx->fscache_uniq); 1233 } 1234 } 1235 1236 return nfs_fscache_get_super_cookie(sb, uniq, ulen); 1237 } 1238 #else 1239 static int nfs_get_cache_cookie(struct super_block *sb, 1240 struct nfs_fs_context *ctx) 1241 { 1242 return 0; 1243 } 1244 #endif 1245 1246 int nfs_get_tree_common(struct fs_context *fc) 1247 { 1248 struct nfs_fs_context *ctx = nfs_fc2context(fc); 1249 struct super_block *s; 1250 int (*compare_super)(struct super_block *, struct fs_context *) = nfs_compare_super; 1251 struct nfs_server *server = ctx->server; 1252 int error; 1253 1254 ctx->server = NULL; 1255 if (IS_ERR(server)) 1256 return PTR_ERR(server); 1257 1258 if (server->flags & NFS_MOUNT_UNSHARED) 1259 compare_super = NULL; 1260 1261 /* -o noac implies -o sync */ 1262 if (server->flags & NFS_MOUNT_NOAC) 1263 fc->sb_flags |= SB_SYNCHRONOUS; 1264 1265 if (ctx->clone_data.sb) 1266 if (ctx->clone_data.sb->s_flags & SB_SYNCHRONOUS) 1267 fc->sb_flags |= SB_SYNCHRONOUS; 1268 1269 if (server->caps & NFS_CAP_SECURITY_LABEL) 1270 fc->lsm_flags |= SECURITY_LSM_NATIVE_LABELS; 1271 1272 /* Get a superblock - note that we may end up sharing one that already exists */ 1273 fc->s_fs_info = server; 1274 s = sget_fc(fc, compare_super, nfs_set_super); 1275 fc->s_fs_info = NULL; 1276 if (IS_ERR(s)) { 1277 error = PTR_ERR(s); 1278 nfs_errorf(fc, "NFS: Couldn't get superblock"); 1279 goto out_err_nosb; 1280 } 1281 1282 if (s->s_fs_info != server) { 1283 nfs_free_server(server); 1284 server = NULL; 1285 } else { 1286 error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev), 1287 MINOR(server->s_dev)); 1288 if (error) 1289 goto error_splat_super; 1290 s->s_bdi->io_pages = server->rpages; 1291 server->super = s; 1292 } 1293 1294 if (!s->s_root) { 1295 unsigned bsize = ctx->clone_data.inherited_bsize; 1296 /* initial superblock/root creation */ 1297 nfs_fill_super(s, ctx); 1298 if (bsize) { 1299 s->s_blocksize_bits = bsize; 1300 s->s_blocksize = 1U << bsize; 1301 } 1302 error = nfs_get_cache_cookie(s, ctx); 1303 if (error < 0) 1304 goto error_splat_super; 1305 } 1306 1307 error = nfs_get_root(s, fc); 1308 if (error < 0) { 1309 nfs_errorf(fc, "NFS: Couldn't get root dentry"); 1310 goto error_splat_super; 1311 } 1312 1313 s->s_flags |= SB_ACTIVE; 1314 error = 0; 1315 1316 out: 1317 return error; 1318 1319 out_err_nosb: 1320 nfs_free_server(server); 1321 goto out; 1322 error_splat_super: 1323 deactivate_locked_super(s); 1324 goto out; 1325 } 1326 1327 /* 1328 * Destroy an NFS2/3 superblock 1329 */ 1330 void nfs_kill_super(struct super_block *s) 1331 { 1332 struct nfs_server *server = NFS_SB(s); 1333 dev_t dev = s->s_dev; 1334 1335 generic_shutdown_super(s); 1336 1337 nfs_fscache_release_super_cookie(s); 1338 1339 nfs_free_server(server); 1340 free_anon_bdev(dev); 1341 } 1342 EXPORT_SYMBOL_GPL(nfs_kill_super); 1343 1344 #if IS_ENABLED(CONFIG_NFS_V4) 1345 1346 /* 1347 * NFS v4 module parameters need to stay in the 1348 * NFS client for backwards compatibility 1349 */ 1350 unsigned int nfs_callback_set_tcpport; 1351 unsigned short nfs_callback_nr_threads; 1352 /* Default cache timeout is 10 minutes */ 1353 unsigned int nfs_idmap_cache_timeout = 600; 1354 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */ 1355 bool nfs4_disable_idmapping = true; 1356 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE; 1357 unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE; 1358 unsigned short send_implementation_id = 1; 1359 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = ""; 1360 bool recover_lost_locks = false; 1361 1362 EXPORT_SYMBOL_GPL(nfs_callback_nr_threads); 1363 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport); 1364 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout); 1365 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping); 1366 EXPORT_SYMBOL_GPL(max_session_slots); 1367 EXPORT_SYMBOL_GPL(max_session_cb_slots); 1368 EXPORT_SYMBOL_GPL(send_implementation_id); 1369 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier); 1370 EXPORT_SYMBOL_GPL(recover_lost_locks); 1371 1372 #define NFS_CALLBACK_MAXPORTNR (65535U) 1373 1374 static int param_set_portnr(const char *val, const struct kernel_param *kp) 1375 { 1376 unsigned long num; 1377 int ret; 1378 1379 if (!val) 1380 return -EINVAL; 1381 ret = kstrtoul(val, 0, &num); 1382 if (ret || num > NFS_CALLBACK_MAXPORTNR) 1383 return -EINVAL; 1384 *((unsigned int *)kp->arg) = num; 1385 return 0; 1386 } 1387 static const struct kernel_param_ops param_ops_portnr = { 1388 .set = param_set_portnr, 1389 .get = param_get_uint, 1390 }; 1391 #define param_check_portnr(name, p) __param_check(name, p, unsigned int) 1392 1393 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644); 1394 module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644); 1395 MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be " 1396 "assigned to the NFSv4 callback channels."); 1397 module_param(nfs_idmap_cache_timeout, int, 0644); 1398 module_param(nfs4_disable_idmapping, bool, 0644); 1399 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier, 1400 NFS4_CLIENT_ID_UNIQ_LEN, 0600); 1401 MODULE_PARM_DESC(nfs4_disable_idmapping, 1402 "Turn off NFSv4 idmapping when using 'sec=sys'"); 1403 module_param(max_session_slots, ushort, 0644); 1404 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 " 1405 "requests the client will negotiate"); 1406 module_param(max_session_cb_slots, ushort, 0644); 1407 MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 " 1408 "callbacks the client will process for a given server"); 1409 module_param(send_implementation_id, ushort, 0644); 1410 MODULE_PARM_DESC(send_implementation_id, 1411 "Send implementation ID with NFSv4.1 exchange_id"); 1412 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string"); 1413 1414 module_param(recover_lost_locks, bool, 0644); 1415 MODULE_PARM_DESC(recover_lost_locks, 1416 "If the server reports that a lock might be lost, " 1417 "try to recover it risking data corruption."); 1418 1419 1420 #endif /* CONFIG_NFS_V4 */ 1421