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 <uapi/linux/tls.h> 63 64 #include "nfs4_fs.h" 65 #include "callback.h" 66 #include "delegation.h" 67 #include "iostat.h" 68 #include "internal.h" 69 #include "fscache.h" 70 #include "nfs4session.h" 71 #include "pnfs.h" 72 #include "nfs.h" 73 #include "netns.h" 74 #include "sysfs.h" 75 76 #define NFSDBG_FACILITY NFSDBG_VFS 77 78 const struct super_operations nfs_sops = { 79 .alloc_inode = nfs_alloc_inode, 80 .free_inode = nfs_free_inode, 81 .write_inode = nfs_write_inode, 82 .drop_inode = nfs_drop_inode, 83 .statfs = nfs_statfs, 84 .evict_inode = nfs_evict_inode, 85 .umount_begin = nfs_umount_begin, 86 .show_options = nfs_show_options, 87 .show_devname = nfs_show_devname, 88 .show_path = nfs_show_path, 89 .show_stats = nfs_show_stats, 90 }; 91 EXPORT_SYMBOL_GPL(nfs_sops); 92 93 #ifdef CONFIG_NFS_V4_2 94 static const struct nfs_ssc_client_ops nfs_ssc_clnt_ops_tbl = { 95 .sco_sb_deactive = nfs_sb_deactive, 96 }; 97 #endif 98 99 #if IS_ENABLED(CONFIG_NFS_V4) 100 static int __init register_nfs4_fs(void) 101 { 102 return register_filesystem(&nfs4_fs_type); 103 } 104 105 static void unregister_nfs4_fs(void) 106 { 107 unregister_filesystem(&nfs4_fs_type); 108 } 109 #else 110 static int __init register_nfs4_fs(void) 111 { 112 return 0; 113 } 114 115 static void unregister_nfs4_fs(void) 116 { 117 } 118 #endif 119 120 #ifdef CONFIG_NFS_V4_2 121 static void nfs_ssc_register_ops(void) 122 { 123 nfs_ssc_register(&nfs_ssc_clnt_ops_tbl); 124 } 125 126 static void nfs_ssc_unregister_ops(void) 127 { 128 nfs_ssc_unregister(&nfs_ssc_clnt_ops_tbl); 129 } 130 #endif /* CONFIG_NFS_V4_2 */ 131 132 static struct shrinker acl_shrinker = { 133 .count_objects = nfs_access_cache_count, 134 .scan_objects = nfs_access_cache_scan, 135 .seeks = DEFAULT_SEEKS, 136 }; 137 138 /* 139 * Register the NFS filesystems 140 */ 141 int __init register_nfs_fs(void) 142 { 143 int ret; 144 145 ret = register_filesystem(&nfs_fs_type); 146 if (ret < 0) 147 goto error_0; 148 149 ret = register_nfs4_fs(); 150 if (ret < 0) 151 goto error_1; 152 153 ret = nfs_register_sysctl(); 154 if (ret < 0) 155 goto error_2; 156 ret = register_shrinker(&acl_shrinker, "nfs-acl"); 157 if (ret < 0) 158 goto error_3; 159 #ifdef CONFIG_NFS_V4_2 160 nfs_ssc_register_ops(); 161 #endif 162 return 0; 163 error_3: 164 nfs_unregister_sysctl(); 165 error_2: 166 unregister_nfs4_fs(); 167 error_1: 168 unregister_filesystem(&nfs_fs_type); 169 error_0: 170 return ret; 171 } 172 173 /* 174 * Unregister the NFS filesystems 175 */ 176 void __exit unregister_nfs_fs(void) 177 { 178 unregister_shrinker(&acl_shrinker); 179 nfs_unregister_sysctl(); 180 unregister_nfs4_fs(); 181 #ifdef CONFIG_NFS_V4_2 182 nfs_ssc_unregister_ops(); 183 #endif 184 unregister_filesystem(&nfs_fs_type); 185 } 186 187 bool nfs_sb_active(struct super_block *sb) 188 { 189 struct nfs_server *server = NFS_SB(sb); 190 191 if (!atomic_inc_not_zero(&sb->s_active)) 192 return false; 193 if (atomic_inc_return(&server->active) != 1) 194 atomic_dec(&sb->s_active); 195 return true; 196 } 197 EXPORT_SYMBOL_GPL(nfs_sb_active); 198 199 void nfs_sb_deactive(struct super_block *sb) 200 { 201 struct nfs_server *server = NFS_SB(sb); 202 203 if (atomic_dec_and_test(&server->active)) 204 deactivate_super(sb); 205 } 206 EXPORT_SYMBOL_GPL(nfs_sb_deactive); 207 208 static int __nfs_list_for_each_server(struct list_head *head, 209 int (*fn)(struct nfs_server *, void *), 210 void *data) 211 { 212 struct nfs_server *server, *last = NULL; 213 int ret = 0; 214 215 rcu_read_lock(); 216 list_for_each_entry_rcu(server, head, client_link) { 217 if (!(server->super && nfs_sb_active(server->super))) 218 continue; 219 rcu_read_unlock(); 220 if (last) 221 nfs_sb_deactive(last->super); 222 last = server; 223 ret = fn(server, data); 224 if (ret) 225 goto out; 226 rcu_read_lock(); 227 } 228 rcu_read_unlock(); 229 out: 230 if (last) 231 nfs_sb_deactive(last->super); 232 return ret; 233 } 234 235 int nfs_client_for_each_server(struct nfs_client *clp, 236 int (*fn)(struct nfs_server *, void *), 237 void *data) 238 { 239 return __nfs_list_for_each_server(&clp->cl_superblocks, fn, data); 240 } 241 EXPORT_SYMBOL_GPL(nfs_client_for_each_server); 242 243 /* 244 * Deliver file system statistics to userspace 245 */ 246 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf) 247 { 248 struct nfs_server *server = NFS_SB(dentry->d_sb); 249 unsigned char blockbits; 250 unsigned long blockres; 251 struct nfs_fh *fh = NFS_FH(d_inode(dentry)); 252 struct nfs_fsstat res; 253 int error = -ENOMEM; 254 255 res.fattr = nfs_alloc_fattr(); 256 if (res.fattr == NULL) 257 goto out_err; 258 259 error = server->nfs_client->rpc_ops->statfs(server, fh, &res); 260 if (unlikely(error == -ESTALE)) { 261 struct dentry *pd_dentry; 262 263 pd_dentry = dget_parent(dentry); 264 nfs_zap_caches(d_inode(pd_dentry)); 265 dput(pd_dentry); 266 } 267 nfs_free_fattr(res.fattr); 268 if (error < 0) 269 goto out_err; 270 271 buf->f_type = NFS_SUPER_MAGIC; 272 273 /* 274 * Current versions of glibc do not correctly handle the 275 * case where f_frsize != f_bsize. Eventually we want to 276 * report the value of wtmult in this field. 277 */ 278 buf->f_frsize = dentry->d_sb->s_blocksize; 279 280 /* 281 * On most *nix systems, f_blocks, f_bfree, and f_bavail 282 * are reported in units of f_frsize. Linux hasn't had 283 * an f_frsize field in its statfs struct until recently, 284 * thus historically Linux's sys_statfs reports these 285 * fields in units of f_bsize. 286 */ 287 buf->f_bsize = dentry->d_sb->s_blocksize; 288 blockbits = dentry->d_sb->s_blocksize_bits; 289 blockres = (1 << blockbits) - 1; 290 buf->f_blocks = (res.tbytes + blockres) >> blockbits; 291 buf->f_bfree = (res.fbytes + blockres) >> blockbits; 292 buf->f_bavail = (res.abytes + blockres) >> blockbits; 293 294 buf->f_files = res.tfiles; 295 buf->f_ffree = res.afiles; 296 297 buf->f_namelen = server->namelen; 298 299 return 0; 300 301 out_err: 302 dprintk("%s: statfs error = %d\n", __func__, -error); 303 return error; 304 } 305 EXPORT_SYMBOL_GPL(nfs_statfs); 306 307 /* 308 * Map the security flavour number to a name 309 */ 310 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour) 311 { 312 static const struct { 313 rpc_authflavor_t flavour; 314 const char *str; 315 } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = { 316 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */ 317 { RPC_AUTH_NULL, "null" }, 318 { RPC_AUTH_UNIX, "sys" }, 319 { RPC_AUTH_GSS_KRB5, "krb5" }, 320 { RPC_AUTH_GSS_KRB5I, "krb5i" }, 321 { RPC_AUTH_GSS_KRB5P, "krb5p" }, 322 { RPC_AUTH_GSS_LKEY, "lkey" }, 323 { RPC_AUTH_GSS_LKEYI, "lkeyi" }, 324 { RPC_AUTH_GSS_LKEYP, "lkeyp" }, 325 { RPC_AUTH_GSS_SPKM, "spkm" }, 326 { RPC_AUTH_GSS_SPKMI, "spkmi" }, 327 { RPC_AUTH_GSS_SPKMP, "spkmp" }, 328 { UINT_MAX, "unknown" } 329 }; 330 int i; 331 332 for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) { 333 if (sec_flavours[i].flavour == flavour) 334 break; 335 } 336 return sec_flavours[i].str; 337 } 338 339 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss, 340 int showdefaults) 341 { 342 struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address; 343 char *proto = NULL; 344 345 switch (sap->sa_family) { 346 case AF_INET: 347 switch (nfss->mountd_protocol) { 348 case IPPROTO_UDP: 349 proto = RPCBIND_NETID_UDP; 350 break; 351 case IPPROTO_TCP: 352 proto = RPCBIND_NETID_TCP; 353 break; 354 } 355 break; 356 case AF_INET6: 357 switch (nfss->mountd_protocol) { 358 case IPPROTO_UDP: 359 proto = RPCBIND_NETID_UDP6; 360 break; 361 case IPPROTO_TCP: 362 proto = RPCBIND_NETID_TCP6; 363 break; 364 } 365 break; 366 } 367 if (proto || showdefaults) 368 seq_printf(m, ",mountproto=%s", proto ?: "auto"); 369 } 370 371 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss, 372 int showdefaults) 373 { 374 struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address; 375 376 if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE) 377 return; 378 379 switch (sap->sa_family) { 380 case AF_INET: { 381 struct sockaddr_in *sin = (struct sockaddr_in *)sap; 382 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr); 383 break; 384 } 385 case AF_INET6: { 386 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap; 387 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr); 388 break; 389 } 390 default: 391 if (showdefaults) 392 seq_puts(m, ",mountaddr=unspecified"); 393 } 394 395 if (nfss->mountd_version || showdefaults) 396 seq_printf(m, ",mountvers=%u", nfss->mountd_version); 397 if ((nfss->mountd_port && 398 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) || 399 showdefaults) 400 seq_printf(m, ",mountport=%u", nfss->mountd_port); 401 402 nfs_show_mountd_netid(m, nfss, showdefaults); 403 } 404 405 #if IS_ENABLED(CONFIG_NFS_V4) 406 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss, 407 int showdefaults) 408 { 409 struct nfs_client *clp = nfss->nfs_client; 410 411 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr); 412 } 413 #else 414 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss, 415 int showdefaults) 416 { 417 } 418 #endif 419 420 static void nfs_show_nfs_version(struct seq_file *m, 421 unsigned int version, 422 unsigned int minorversion) 423 { 424 seq_printf(m, ",vers=%u", version); 425 if (version == 4) 426 seq_printf(m, ".%u", minorversion); 427 } 428 429 /* 430 * Describe the mount options in force on this server representation 431 */ 432 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, 433 int showdefaults) 434 { 435 static const struct proc_nfs_info { 436 int flag; 437 const char *str; 438 const char *nostr; 439 } nfs_info[] = { 440 { NFS_MOUNT_SOFT, ",soft", "" }, 441 { NFS_MOUNT_SOFTERR, ",softerr", "" }, 442 { NFS_MOUNT_SOFTREVAL, ",softreval", "" }, 443 { NFS_MOUNT_POSIX, ",posix", "" }, 444 { NFS_MOUNT_NOCTO, ",nocto", "" }, 445 { NFS_MOUNT_NOAC, ",noac", "" }, 446 { NFS_MOUNT_NONLM, ",nolock", "" }, 447 { NFS_MOUNT_NOACL, ",noacl", "" }, 448 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" }, 449 { NFS_MOUNT_UNSHARED, ",nosharecache", "" }, 450 { NFS_MOUNT_NORESVPORT, ",noresvport", "" }, 451 { 0, NULL, NULL } 452 }; 453 const struct proc_nfs_info *nfs_infop; 454 struct nfs_client *clp = nfss->nfs_client; 455 u32 version = clp->rpc_ops->version; 456 int local_flock, local_fcntl; 457 458 nfs_show_nfs_version(m, version, clp->cl_minorversion); 459 seq_printf(m, ",rsize=%u", nfss->rsize); 460 seq_printf(m, ",wsize=%u", nfss->wsize); 461 if (nfss->bsize != 0) 462 seq_printf(m, ",bsize=%u", nfss->bsize); 463 seq_printf(m, ",namlen=%u", nfss->namelen); 464 if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults) 465 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ); 466 if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults) 467 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ); 468 if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults) 469 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ); 470 if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults) 471 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ); 472 if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))) 473 seq_puts(m, ",hard"); 474 for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) { 475 if (nfss->flags & nfs_infop->flag) 476 seq_puts(m, nfs_infop->str); 477 else 478 seq_puts(m, nfs_infop->nostr); 479 } 480 rcu_read_lock(); 481 seq_printf(m, ",proto=%s", 482 rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID)); 483 rcu_read_unlock(); 484 if (clp->cl_nconnect > 0) 485 seq_printf(m, ",nconnect=%u", clp->cl_nconnect); 486 if (version == 4) { 487 if (clp->cl_max_connect > 1) 488 seq_printf(m, ",max_connect=%u", clp->cl_max_connect); 489 if (nfss->port != NFS_PORT) 490 seq_printf(m, ",port=%u", nfss->port); 491 } else 492 if (nfss->port) 493 seq_printf(m, ",port=%u", nfss->port); 494 495 seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ); 496 seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries); 497 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor)); 498 switch (clp->cl_xprtsec.policy) { 499 case RPC_XPRTSEC_TLS_ANON: 500 seq_puts(m, ",xprtsec=tls"); 501 break; 502 case RPC_XPRTSEC_TLS_X509: 503 seq_puts(m, ",xprtsec=mtls"); 504 break; 505 default: 506 break; 507 } 508 509 if (version != 4) 510 nfs_show_mountd_options(m, nfss, showdefaults); 511 else 512 nfs_show_nfsv4_options(m, nfss, showdefaults); 513 514 if (nfss->options & NFS_OPTION_FSCACHE) 515 seq_puts(m, ",fsc"); 516 517 if (nfss->options & NFS_OPTION_MIGRATION) 518 seq_puts(m, ",migration"); 519 520 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) { 521 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE) 522 seq_puts(m, ",lookupcache=none"); 523 else 524 seq_puts(m, ",lookupcache=pos"); 525 } 526 527 local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK; 528 local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL; 529 530 if (!local_flock && !local_fcntl) 531 seq_puts(m, ",local_lock=none"); 532 else if (local_flock && local_fcntl) 533 seq_puts(m, ",local_lock=all"); 534 else if (local_flock) 535 seq_puts(m, ",local_lock=flock"); 536 else 537 seq_puts(m, ",local_lock=posix"); 538 539 if (nfss->flags & NFS_MOUNT_WRITE_EAGER) { 540 if (nfss->flags & NFS_MOUNT_WRITE_WAIT) 541 seq_puts(m, ",write=wait"); 542 else 543 seq_puts(m, ",write=eager"); 544 } 545 } 546 547 /* 548 * Describe the mount options on this VFS mountpoint 549 */ 550 int nfs_show_options(struct seq_file *m, struct dentry *root) 551 { 552 struct nfs_server *nfss = NFS_SB(root->d_sb); 553 554 nfs_show_mount_options(m, nfss, 0); 555 556 rcu_read_lock(); 557 seq_printf(m, ",addr=%s", 558 rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient, 559 RPC_DISPLAY_ADDR)); 560 rcu_read_unlock(); 561 562 return 0; 563 } 564 EXPORT_SYMBOL_GPL(nfs_show_options); 565 566 #if IS_ENABLED(CONFIG_NFS_V4) 567 static void show_lease(struct seq_file *m, struct nfs_server *server) 568 { 569 struct nfs_client *clp = server->nfs_client; 570 unsigned long expire; 571 572 seq_printf(m, ",lease_time=%ld", clp->cl_lease_time / HZ); 573 expire = clp->cl_last_renewal + clp->cl_lease_time; 574 seq_printf(m, ",lease_expired=%ld", 575 time_after(expire, jiffies) ? 0 : (jiffies - expire) / HZ); 576 } 577 #ifdef CONFIG_NFS_V4_1 578 static void show_sessions(struct seq_file *m, struct nfs_server *server) 579 { 580 if (nfs4_has_session(server->nfs_client)) 581 seq_puts(m, ",sessions"); 582 } 583 #else 584 static void show_sessions(struct seq_file *m, struct nfs_server *server) {} 585 #endif 586 #endif 587 588 #ifdef CONFIG_NFS_V4_1 589 static void show_pnfs(struct seq_file *m, struct nfs_server *server) 590 { 591 seq_printf(m, ",pnfs="); 592 if (server->pnfs_curr_ld) 593 seq_printf(m, "%s", server->pnfs_curr_ld->name); 594 else 595 seq_printf(m, "not configured"); 596 } 597 598 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss) 599 { 600 if (nfss->nfs_client && nfss->nfs_client->cl_implid) { 601 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid; 602 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s'," 603 "date='%llu,%u'", 604 impl_id->name, impl_id->domain, 605 impl_id->date.seconds, impl_id->date.nseconds); 606 } 607 } 608 #else 609 #if IS_ENABLED(CONFIG_NFS_V4) 610 static void show_pnfs(struct seq_file *m, struct nfs_server *server) 611 { 612 } 613 #endif 614 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss) 615 { 616 } 617 #endif 618 619 int nfs_show_devname(struct seq_file *m, struct dentry *root) 620 { 621 char *page = (char *) __get_free_page(GFP_KERNEL); 622 char *devname, *dummy; 623 int err = 0; 624 if (!page) 625 return -ENOMEM; 626 devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0); 627 if (IS_ERR(devname)) 628 err = PTR_ERR(devname); 629 else 630 seq_escape(m, devname, " \t\n\\"); 631 free_page((unsigned long)page); 632 return err; 633 } 634 EXPORT_SYMBOL_GPL(nfs_show_devname); 635 636 int nfs_show_path(struct seq_file *m, struct dentry *dentry) 637 { 638 seq_puts(m, "/"); 639 return 0; 640 } 641 EXPORT_SYMBOL_GPL(nfs_show_path); 642 643 /* 644 * Present statistical information for this VFS mountpoint 645 */ 646 int nfs_show_stats(struct seq_file *m, struct dentry *root) 647 { 648 int i, cpu; 649 struct nfs_server *nfss = NFS_SB(root->d_sb); 650 struct rpc_auth *auth = nfss->client->cl_auth; 651 struct nfs_iostats totals = { }; 652 653 seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS); 654 655 /* 656 * Display all mount option settings 657 */ 658 seq_puts(m, "\n\topts:\t"); 659 seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw"); 660 seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : ""); 661 seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : ""); 662 seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : ""); 663 nfs_show_mount_options(m, nfss, 1); 664 665 seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ); 666 667 show_implementation_id(m, nfss); 668 669 seq_puts(m, "\n\tcaps:\t"); 670 seq_printf(m, "caps=0x%x", nfss->caps); 671 seq_printf(m, ",wtmult=%u", nfss->wtmult); 672 seq_printf(m, ",dtsize=%u", nfss->dtsize); 673 seq_printf(m, ",bsize=%u", nfss->bsize); 674 seq_printf(m, ",namlen=%u", nfss->namelen); 675 676 #if IS_ENABLED(CONFIG_NFS_V4) 677 if (nfss->nfs_client->rpc_ops->version == 4) { 678 seq_puts(m, "\n\tnfsv4:\t"); 679 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]); 680 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]); 681 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]); 682 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask); 683 show_sessions(m, nfss); 684 show_pnfs(m, nfss); 685 show_lease(m, nfss); 686 } 687 #endif 688 689 /* 690 * Display security flavor in effect for this mount 691 */ 692 seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor); 693 if (auth->au_flavor) 694 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor); 695 696 /* 697 * Display superblock I/O counters 698 */ 699 for_each_possible_cpu(cpu) { 700 struct nfs_iostats *stats; 701 702 preempt_disable(); 703 stats = per_cpu_ptr(nfss->io_stats, cpu); 704 705 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 706 totals.events[i] += stats->events[i]; 707 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 708 totals.bytes[i] += stats->bytes[i]; 709 710 preempt_enable(); 711 } 712 713 seq_puts(m, "\n\tevents:\t"); 714 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 715 seq_printf(m, "%lu ", totals.events[i]); 716 seq_puts(m, "\n\tbytes:\t"); 717 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 718 seq_printf(m, "%Lu ", totals.bytes[i]); 719 seq_putc(m, '\n'); 720 721 rpc_clnt_show_stats(m, nfss->client); 722 723 return 0; 724 } 725 EXPORT_SYMBOL_GPL(nfs_show_stats); 726 727 /* 728 * Begin unmount by attempting to remove all automounted mountpoints we added 729 * in response to xdev traversals and referrals 730 */ 731 void nfs_umount_begin(struct super_block *sb) 732 { 733 struct nfs_server *server; 734 struct rpc_clnt *rpc; 735 736 server = NFS_SB(sb); 737 /* -EIO all pending I/O */ 738 rpc = server->client_acl; 739 if (!IS_ERR(rpc)) 740 rpc_killall_tasks(rpc); 741 rpc = server->client; 742 if (!IS_ERR(rpc)) 743 rpc_killall_tasks(rpc); 744 } 745 EXPORT_SYMBOL_GPL(nfs_umount_begin); 746 747 /* 748 * Return true if 'match' is in auth_info or auth_info is empty. 749 * Return false otherwise. 750 */ 751 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info, 752 rpc_authflavor_t match) 753 { 754 int i; 755 756 if (!auth_info->flavor_len) 757 return true; 758 759 for (i = 0; i < auth_info->flavor_len; i++) { 760 if (auth_info->flavors[i] == match) 761 return true; 762 } 763 return false; 764 } 765 EXPORT_SYMBOL_GPL(nfs_auth_info_match); 766 767 /* 768 * Ensure that a specified authtype in ctx->auth_info is supported by 769 * the server. Returns 0 and sets ctx->selected_flavor if it's ok, and 770 * -EACCES if not. 771 */ 772 static int nfs_verify_authflavors(struct nfs_fs_context *ctx, 773 rpc_authflavor_t *server_authlist, 774 unsigned int count) 775 { 776 rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR; 777 bool found_auth_null = false; 778 unsigned int i; 779 780 /* 781 * If the sec= mount option is used, the specified flavor or AUTH_NULL 782 * must be in the list returned by the server. 783 * 784 * AUTH_NULL has a special meaning when it's in the server list - it 785 * means that the server will ignore the rpc creds, so any flavor 786 * can be used but still use the sec= that was specified. 787 * 788 * Note also that the MNT procedure in MNTv1 does not return a list 789 * of supported security flavors. In this case, nfs_mount() fabricates 790 * a security flavor list containing just AUTH_NULL. 791 */ 792 for (i = 0; i < count; i++) { 793 flavor = server_authlist[i]; 794 795 if (nfs_auth_info_match(&ctx->auth_info, flavor)) 796 goto out; 797 798 if (flavor == RPC_AUTH_NULL) 799 found_auth_null = true; 800 } 801 802 if (found_auth_null) { 803 flavor = ctx->auth_info.flavors[0]; 804 goto out; 805 } 806 807 dfprintk(MOUNT, 808 "NFS: specified auth flavors not supported by server\n"); 809 return -EACCES; 810 811 out: 812 ctx->selected_flavor = flavor; 813 dfprintk(MOUNT, "NFS: using auth flavor %u\n", ctx->selected_flavor); 814 return 0; 815 } 816 817 /* 818 * Use the remote server's MOUNT service to request the NFS file handle 819 * corresponding to the provided path. 820 */ 821 static int nfs_request_mount(struct fs_context *fc, 822 struct nfs_fh *root_fh, 823 rpc_authflavor_t *server_authlist, 824 unsigned int *server_authlist_len) 825 { 826 struct nfs_fs_context *ctx = nfs_fc2context(fc); 827 struct nfs_mount_request request = { 828 .sap = &ctx->mount_server._address, 829 .dirpath = ctx->nfs_server.export_path, 830 .protocol = ctx->mount_server.protocol, 831 .fh = root_fh, 832 .noresvport = ctx->flags & NFS_MOUNT_NORESVPORT, 833 .auth_flav_len = server_authlist_len, 834 .auth_flavs = server_authlist, 835 .net = fc->net_ns, 836 }; 837 int status; 838 839 if (ctx->mount_server.version == 0) { 840 switch (ctx->version) { 841 default: 842 ctx->mount_server.version = NFS_MNT3_VERSION; 843 break; 844 case 2: 845 ctx->mount_server.version = NFS_MNT_VERSION; 846 } 847 } 848 request.version = ctx->mount_server.version; 849 850 if (ctx->mount_server.hostname) 851 request.hostname = ctx->mount_server.hostname; 852 else 853 request.hostname = ctx->nfs_server.hostname; 854 855 /* 856 * Construct the mount server's address. 857 */ 858 if (ctx->mount_server.address.sa_family == AF_UNSPEC) { 859 memcpy(request.sap, &ctx->nfs_server._address, 860 ctx->nfs_server.addrlen); 861 ctx->mount_server.addrlen = ctx->nfs_server.addrlen; 862 } 863 request.salen = ctx->mount_server.addrlen; 864 nfs_set_port(request.sap, &ctx->mount_server.port, 0); 865 866 /* 867 * Now ask the mount server to map our export path 868 * to a file handle. 869 */ 870 status = nfs_mount(&request, ctx->timeo, ctx->retrans); 871 if (status != 0) { 872 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n", 873 request.hostname, status); 874 return status; 875 } 876 877 return 0; 878 } 879 880 static struct nfs_server *nfs_try_mount_request(struct fs_context *fc) 881 { 882 struct nfs_fs_context *ctx = nfs_fc2context(fc); 883 int status; 884 unsigned int i; 885 bool tried_auth_unix = false; 886 bool auth_null_in_list = false; 887 struct nfs_server *server = ERR_PTR(-EACCES); 888 rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS]; 889 unsigned int authlist_len = ARRAY_SIZE(authlist); 890 891 status = nfs_request_mount(fc, ctx->mntfh, authlist, &authlist_len); 892 if (status) 893 return ERR_PTR(status); 894 895 /* 896 * Was a sec= authflavor specified in the options? First, verify 897 * whether the server supports it, and then just try to use it if so. 898 */ 899 if (ctx->auth_info.flavor_len > 0) { 900 status = nfs_verify_authflavors(ctx, authlist, authlist_len); 901 dfprintk(MOUNT, "NFS: using auth flavor %u\n", 902 ctx->selected_flavor); 903 if (status) 904 return ERR_PTR(status); 905 return ctx->nfs_mod->rpc_ops->create_server(fc); 906 } 907 908 /* 909 * No sec= option was provided. RFC 2623, section 2.7 suggests we 910 * SHOULD prefer the flavor listed first. However, some servers list 911 * AUTH_NULL first. Avoid ever choosing AUTH_NULL. 912 */ 913 for (i = 0; i < authlist_len; ++i) { 914 rpc_authflavor_t flavor; 915 struct rpcsec_gss_info info; 916 917 flavor = authlist[i]; 918 switch (flavor) { 919 case RPC_AUTH_UNIX: 920 tried_auth_unix = true; 921 break; 922 case RPC_AUTH_NULL: 923 auth_null_in_list = true; 924 continue; 925 default: 926 if (rpcauth_get_gssinfo(flavor, &info) != 0) 927 continue; 928 break; 929 } 930 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor); 931 ctx->selected_flavor = flavor; 932 server = ctx->nfs_mod->rpc_ops->create_server(fc); 933 if (!IS_ERR(server)) 934 return server; 935 } 936 937 /* 938 * Nothing we tried so far worked. At this point, give up if we've 939 * already tried AUTH_UNIX or if the server's list doesn't contain 940 * AUTH_NULL 941 */ 942 if (tried_auth_unix || !auth_null_in_list) 943 return server; 944 945 /* Last chance! Try AUTH_UNIX */ 946 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX); 947 ctx->selected_flavor = RPC_AUTH_UNIX; 948 return ctx->nfs_mod->rpc_ops->create_server(fc); 949 } 950 951 int nfs_try_get_tree(struct fs_context *fc) 952 { 953 struct nfs_fs_context *ctx = nfs_fc2context(fc); 954 955 if (ctx->need_mount) 956 ctx->server = nfs_try_mount_request(fc); 957 else 958 ctx->server = ctx->nfs_mod->rpc_ops->create_server(fc); 959 960 return nfs_get_tree_common(fc); 961 } 962 EXPORT_SYMBOL_GPL(nfs_try_get_tree); 963 964 965 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \ 966 | NFS_MOUNT_SECURE \ 967 | NFS_MOUNT_TCP \ 968 | NFS_MOUNT_VER3 \ 969 | NFS_MOUNT_KERBEROS \ 970 | NFS_MOUNT_NONLM \ 971 | NFS_MOUNT_BROKEN_SUID \ 972 | NFS_MOUNT_STRICTLOCK \ 973 | NFS_MOUNT_LEGACY_INTERFACE) 974 975 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \ 976 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT)) 977 978 static int 979 nfs_compare_remount_data(struct nfs_server *nfss, 980 struct nfs_fs_context *ctx) 981 { 982 if ((ctx->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK || 983 ctx->rsize != nfss->rsize || 984 ctx->wsize != nfss->wsize || 985 ctx->version != nfss->nfs_client->rpc_ops->version || 986 ctx->minorversion != nfss->nfs_client->cl_minorversion || 987 ctx->retrans != nfss->client->cl_timeout->to_retries || 988 !nfs_auth_info_match(&ctx->auth_info, nfss->client->cl_auth->au_flavor) || 989 ctx->acregmin != nfss->acregmin / HZ || 990 ctx->acregmax != nfss->acregmax / HZ || 991 ctx->acdirmin != nfss->acdirmin / HZ || 992 ctx->acdirmax != nfss->acdirmax / HZ || 993 ctx->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) || 994 (ctx->options & NFS_OPTION_FSCACHE) != (nfss->options & NFS_OPTION_FSCACHE) || 995 ctx->nfs_server.port != nfss->port || 996 ctx->nfs_server.addrlen != nfss->nfs_client->cl_addrlen || 997 !rpc_cmp_addr((struct sockaddr *)&ctx->nfs_server.address, 998 (struct sockaddr *)&nfss->nfs_client->cl_addr)) 999 return -EINVAL; 1000 1001 return 0; 1002 } 1003 1004 int nfs_reconfigure(struct fs_context *fc) 1005 { 1006 struct nfs_fs_context *ctx = nfs_fc2context(fc); 1007 struct super_block *sb = fc->root->d_sb; 1008 struct nfs_server *nfss = sb->s_fs_info; 1009 int ret; 1010 1011 sync_filesystem(sb); 1012 1013 /* 1014 * Userspace mount programs that send binary options generally send 1015 * them populated with default values. We have no way to know which 1016 * ones were explicitly specified. Fall back to legacy behavior and 1017 * just return success. 1018 */ 1019 if (ctx->skip_reconfig_option_check) 1020 return 0; 1021 1022 /* 1023 * noac is a special case. It implies -o sync, but that's not 1024 * necessarily reflected in the mtab options. reconfigure_super 1025 * will clear SB_SYNCHRONOUS if -o sync wasn't specified in the 1026 * remount options, so we have to explicitly reset it. 1027 */ 1028 if (ctx->flags & NFS_MOUNT_NOAC) { 1029 fc->sb_flags |= SB_SYNCHRONOUS; 1030 fc->sb_flags_mask |= SB_SYNCHRONOUS; 1031 } 1032 1033 /* compare new mount options with old ones */ 1034 ret = nfs_compare_remount_data(nfss, ctx); 1035 if (ret) 1036 return ret; 1037 1038 return nfs_probe_server(nfss, NFS_FH(d_inode(fc->root))); 1039 } 1040 EXPORT_SYMBOL_GPL(nfs_reconfigure); 1041 1042 /* 1043 * Finish setting up an NFS superblock 1044 */ 1045 static void nfs_fill_super(struct super_block *sb, struct nfs_fs_context *ctx) 1046 { 1047 struct nfs_server *server = NFS_SB(sb); 1048 1049 sb->s_blocksize_bits = 0; 1050 sb->s_blocksize = 0; 1051 sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr; 1052 sb->s_op = server->nfs_client->cl_nfs_mod->sops; 1053 if (ctx->bsize) 1054 sb->s_blocksize = nfs_block_size(ctx->bsize, &sb->s_blocksize_bits); 1055 1056 switch (server->nfs_client->rpc_ops->version) { 1057 case 2: 1058 sb->s_time_gran = 1000; 1059 sb->s_time_min = 0; 1060 sb->s_time_max = U32_MAX; 1061 break; 1062 case 3: 1063 /* 1064 * The VFS shouldn't apply the umask to mode bits. 1065 * We will do so ourselves when necessary. 1066 */ 1067 sb->s_flags |= SB_POSIXACL; 1068 sb->s_time_gran = 1; 1069 sb->s_time_min = 0; 1070 sb->s_time_max = U32_MAX; 1071 sb->s_export_op = &nfs_export_ops; 1072 break; 1073 case 4: 1074 sb->s_flags |= SB_POSIXACL; 1075 sb->s_time_gran = 1; 1076 sb->s_time_min = S64_MIN; 1077 sb->s_time_max = S64_MAX; 1078 if (server->caps & NFS_CAP_ATOMIC_OPEN_V1) 1079 sb->s_export_op = &nfs_export_ops; 1080 break; 1081 } 1082 1083 sb->s_magic = NFS_SUPER_MAGIC; 1084 1085 /* We probably want something more informative here */ 1086 snprintf(sb->s_id, sizeof(sb->s_id), 1087 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev)); 1088 1089 if (sb->s_blocksize == 0) 1090 sb->s_blocksize = nfs_block_bits(server->wsize, 1091 &sb->s_blocksize_bits); 1092 1093 nfs_super_set_maxbytes(sb, server->maxfilesize); 1094 nfs_sysfs_move_server_to_sb(sb); 1095 server->has_sec_mnt_opts = ctx->has_sec_mnt_opts; 1096 } 1097 1098 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, 1099 const struct fs_context *fc) 1100 { 1101 const struct nfs_server *a = s->s_fs_info; 1102 const struct rpc_clnt *clnt_a = a->client; 1103 const struct rpc_clnt *clnt_b = b->client; 1104 1105 if ((s->s_flags & NFS_SB_MASK) != (fc->sb_flags & NFS_SB_MASK)) 1106 goto Ebusy; 1107 if (a->nfs_client != b->nfs_client) 1108 goto Ebusy; 1109 if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK) 1110 goto Ebusy; 1111 if (a->wsize != b->wsize) 1112 goto Ebusy; 1113 if (a->rsize != b->rsize) 1114 goto Ebusy; 1115 if (a->acregmin != b->acregmin) 1116 goto Ebusy; 1117 if (a->acregmax != b->acregmax) 1118 goto Ebusy; 1119 if (a->acdirmin != b->acdirmin) 1120 goto Ebusy; 1121 if (a->acdirmax != b->acdirmax) 1122 goto Ebusy; 1123 if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor) 1124 goto Ebusy; 1125 return 1; 1126 Ebusy: 1127 return 0; 1128 } 1129 1130 static int nfs_set_super(struct super_block *s, struct fs_context *fc) 1131 { 1132 struct nfs_server *server = fc->s_fs_info; 1133 int ret; 1134 1135 s->s_d_op = server->nfs_client->rpc_ops->dentry_ops; 1136 ret = set_anon_super(s, server); 1137 if (ret == 0) 1138 server->s_dev = s->s_dev; 1139 return ret; 1140 } 1141 1142 static int nfs_compare_super_address(struct nfs_server *server1, 1143 struct nfs_server *server2) 1144 { 1145 struct sockaddr *sap1, *sap2; 1146 struct rpc_xprt *xprt1 = server1->client->cl_xprt; 1147 struct rpc_xprt *xprt2 = server2->client->cl_xprt; 1148 1149 if (!net_eq(xprt1->xprt_net, xprt2->xprt_net)) 1150 return 0; 1151 1152 sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr; 1153 sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr; 1154 1155 if (sap1->sa_family != sap2->sa_family) 1156 return 0; 1157 1158 switch (sap1->sa_family) { 1159 case AF_INET: { 1160 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1; 1161 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2; 1162 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr) 1163 return 0; 1164 if (sin1->sin_port != sin2->sin_port) 1165 return 0; 1166 break; 1167 } 1168 case AF_INET6: { 1169 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1; 1170 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2; 1171 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr)) 1172 return 0; 1173 if (sin1->sin6_port != sin2->sin6_port) 1174 return 0; 1175 break; 1176 } 1177 default: 1178 return 0; 1179 } 1180 1181 return 1; 1182 } 1183 1184 static int nfs_compare_userns(const struct nfs_server *old, 1185 const struct nfs_server *new) 1186 { 1187 const struct user_namespace *oldns = &init_user_ns; 1188 const struct user_namespace *newns = &init_user_ns; 1189 1190 if (old->client && old->client->cl_cred) 1191 oldns = old->client->cl_cred->user_ns; 1192 if (new->client && new->client->cl_cred) 1193 newns = new->client->cl_cred->user_ns; 1194 if (oldns != newns) 1195 return 0; 1196 return 1; 1197 } 1198 1199 static int nfs_compare_super(struct super_block *sb, struct fs_context *fc) 1200 { 1201 struct nfs_server *server = fc->s_fs_info, *old = NFS_SB(sb); 1202 1203 if (!nfs_compare_super_address(old, server)) 1204 return 0; 1205 /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */ 1206 if (old->flags & NFS_MOUNT_UNSHARED) 1207 return 0; 1208 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0) 1209 return 0; 1210 if (!nfs_compare_userns(old, server)) 1211 return 0; 1212 if ((old->has_sec_mnt_opts || fc->security) && 1213 security_sb_mnt_opts_compat(sb, fc->security)) 1214 return 0; 1215 return nfs_compare_mount_options(sb, server, fc); 1216 } 1217 1218 #ifdef CONFIG_NFS_FSCACHE 1219 static int nfs_get_cache_cookie(struct super_block *sb, 1220 struct nfs_fs_context *ctx) 1221 { 1222 struct nfs_server *nfss = NFS_SB(sb); 1223 char *uniq = NULL; 1224 int ulen = 0; 1225 1226 nfss->fscache = NULL; 1227 1228 if (!ctx) 1229 return 0; 1230 1231 if (ctx->clone_data.sb) { 1232 struct nfs_server *mnt_s = NFS_SB(ctx->clone_data.sb); 1233 if (!(mnt_s->options & NFS_OPTION_FSCACHE)) 1234 return 0; 1235 if (mnt_s->fscache_uniq) { 1236 uniq = mnt_s->fscache_uniq; 1237 ulen = strlen(uniq); 1238 } 1239 } else { 1240 if (!(ctx->options & NFS_OPTION_FSCACHE)) 1241 return 0; 1242 if (ctx->fscache_uniq) { 1243 uniq = ctx->fscache_uniq; 1244 ulen = strlen(ctx->fscache_uniq); 1245 } 1246 } 1247 1248 return nfs_fscache_get_super_cookie(sb, uniq, ulen); 1249 } 1250 #else 1251 static int nfs_get_cache_cookie(struct super_block *sb, 1252 struct nfs_fs_context *ctx) 1253 { 1254 return 0; 1255 } 1256 #endif 1257 1258 int nfs_get_tree_common(struct fs_context *fc) 1259 { 1260 struct nfs_fs_context *ctx = nfs_fc2context(fc); 1261 struct super_block *s; 1262 int (*compare_super)(struct super_block *, struct fs_context *) = nfs_compare_super; 1263 struct nfs_server *server = ctx->server; 1264 int error; 1265 1266 ctx->server = NULL; 1267 if (IS_ERR(server)) 1268 return PTR_ERR(server); 1269 1270 if (server->flags & NFS_MOUNT_UNSHARED) 1271 compare_super = NULL; 1272 1273 /* -o noac implies -o sync */ 1274 if (server->flags & NFS_MOUNT_NOAC) 1275 fc->sb_flags |= SB_SYNCHRONOUS; 1276 1277 if (ctx->clone_data.sb) 1278 if (ctx->clone_data.sb->s_flags & SB_SYNCHRONOUS) 1279 fc->sb_flags |= SB_SYNCHRONOUS; 1280 1281 /* Get a superblock - note that we may end up sharing one that already exists */ 1282 fc->s_fs_info = server; 1283 s = sget_fc(fc, compare_super, nfs_set_super); 1284 fc->s_fs_info = NULL; 1285 if (IS_ERR(s)) { 1286 error = PTR_ERR(s); 1287 nfs_errorf(fc, "NFS: Couldn't get superblock"); 1288 goto out_err_nosb; 1289 } 1290 1291 if (s->s_fs_info != server) { 1292 nfs_free_server(server); 1293 server = NULL; 1294 } else { 1295 error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev), 1296 MINOR(server->s_dev)); 1297 if (error) 1298 goto error_splat_super; 1299 s->s_bdi->io_pages = server->rpages; 1300 server->super = s; 1301 } 1302 1303 if (!s->s_root) { 1304 unsigned bsize = ctx->clone_data.inherited_bsize; 1305 /* initial superblock/root creation */ 1306 nfs_fill_super(s, ctx); 1307 if (bsize) { 1308 s->s_blocksize_bits = bsize; 1309 s->s_blocksize = 1U << bsize; 1310 } 1311 error = nfs_get_cache_cookie(s, ctx); 1312 if (error < 0) 1313 goto error_splat_super; 1314 } 1315 1316 error = nfs_get_root(s, fc); 1317 if (error < 0) { 1318 nfs_errorf(fc, "NFS: Couldn't get root dentry"); 1319 goto error_splat_super; 1320 } 1321 1322 s->s_flags |= SB_ACTIVE; 1323 error = 0; 1324 1325 out: 1326 return error; 1327 1328 out_err_nosb: 1329 nfs_free_server(server); 1330 goto out; 1331 error_splat_super: 1332 deactivate_locked_super(s); 1333 goto out; 1334 } 1335 1336 /* 1337 * Destroy an NFS superblock 1338 */ 1339 void nfs_kill_super(struct super_block *s) 1340 { 1341 struct nfs_server *server = NFS_SB(s); 1342 dev_t dev = s->s_dev; 1343 1344 nfs_sysfs_move_sb_to_server(server); 1345 generic_shutdown_super(s); 1346 1347 nfs_fscache_release_super_cookie(s); 1348 1349 nfs_free_server(server); 1350 free_anon_bdev(dev); 1351 } 1352 EXPORT_SYMBOL_GPL(nfs_kill_super); 1353 1354 #if IS_ENABLED(CONFIG_NFS_V4) 1355 1356 /* 1357 * NFS v4 module parameters need to stay in the 1358 * NFS client for backwards compatibility 1359 */ 1360 unsigned int nfs_callback_set_tcpport; 1361 unsigned short nfs_callback_nr_threads; 1362 /* Default cache timeout is 10 minutes */ 1363 unsigned int nfs_idmap_cache_timeout = 600; 1364 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */ 1365 bool nfs4_disable_idmapping = true; 1366 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE; 1367 unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE; 1368 unsigned short send_implementation_id = 1; 1369 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = ""; 1370 bool recover_lost_locks = false; 1371 1372 EXPORT_SYMBOL_GPL(nfs_callback_nr_threads); 1373 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport); 1374 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout); 1375 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping); 1376 EXPORT_SYMBOL_GPL(max_session_slots); 1377 EXPORT_SYMBOL_GPL(max_session_cb_slots); 1378 EXPORT_SYMBOL_GPL(send_implementation_id); 1379 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier); 1380 EXPORT_SYMBOL_GPL(recover_lost_locks); 1381 1382 #define NFS_CALLBACK_MAXPORTNR (65535U) 1383 1384 static int param_set_portnr(const char *val, const struct kernel_param *kp) 1385 { 1386 unsigned long num; 1387 int ret; 1388 1389 if (!val) 1390 return -EINVAL; 1391 ret = kstrtoul(val, 0, &num); 1392 if (ret || num > NFS_CALLBACK_MAXPORTNR) 1393 return -EINVAL; 1394 *((unsigned int *)kp->arg) = num; 1395 return 0; 1396 } 1397 static const struct kernel_param_ops param_ops_portnr = { 1398 .set = param_set_portnr, 1399 .get = param_get_uint, 1400 }; 1401 #define param_check_portnr(name, p) __param_check(name, p, unsigned int) 1402 1403 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644); 1404 module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644); 1405 MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be " 1406 "assigned to the NFSv4 callback channels."); 1407 module_param(nfs_idmap_cache_timeout, int, 0644); 1408 module_param(nfs4_disable_idmapping, bool, 0644); 1409 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier, 1410 NFS4_CLIENT_ID_UNIQ_LEN, 0600); 1411 MODULE_PARM_DESC(nfs4_disable_idmapping, 1412 "Turn off NFSv4 idmapping when using 'sec=sys'"); 1413 module_param(max_session_slots, ushort, 0644); 1414 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 " 1415 "requests the client will negotiate"); 1416 module_param(max_session_cb_slots, ushort, 0644); 1417 MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 " 1418 "callbacks the client will process for a given server"); 1419 module_param(send_implementation_id, ushort, 0644); 1420 MODULE_PARM_DESC(send_implementation_id, 1421 "Send implementation ID with NFSv4.1 exchange_id"); 1422 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string"); 1423 1424 module_param(recover_lost_locks, bool, 0644); 1425 MODULE_PARM_DESC(recover_lost_locks, 1426 "If the server reports that a lock might be lost, " 1427 "try to recover it risking data corruption."); 1428 1429 1430 #endif /* CONFIG_NFS_V4 */ 1431