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; 133 134 /* 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; 152 153 acl_shrinker = shrinker_alloc(0, "nfs-acl"); 154 if (!acl_shrinker) { 155 ret = -ENOMEM; 156 goto error_3; 157 } 158 159 acl_shrinker->count_objects = nfs_access_cache_count; 160 acl_shrinker->scan_objects = nfs_access_cache_scan; 161 162 shrinker_register(acl_shrinker); 163 164 #ifdef CONFIG_NFS_V4_2 165 nfs_ssc_register_ops(); 166 #endif 167 return 0; 168 error_3: 169 nfs_unregister_sysctl(); 170 error_2: 171 unregister_nfs4_fs(); 172 error_1: 173 unregister_filesystem(&nfs_fs_type); 174 error_0: 175 return ret; 176 } 177 178 /* 179 * Unregister the NFS filesystems 180 */ 181 void __exit unregister_nfs_fs(void) 182 { 183 shrinker_free(acl_shrinker); 184 nfs_unregister_sysctl(); 185 unregister_nfs4_fs(); 186 #ifdef CONFIG_NFS_V4_2 187 nfs_ssc_unregister_ops(); 188 #endif 189 unregister_filesystem(&nfs_fs_type); 190 } 191 192 bool nfs_sb_active(struct super_block *sb) 193 { 194 struct nfs_server *server = NFS_SB(sb); 195 196 if (!atomic_inc_not_zero(&sb->s_active)) 197 return false; 198 if (atomic_inc_return(&server->active) != 1) 199 atomic_dec(&sb->s_active); 200 return true; 201 } 202 EXPORT_SYMBOL_GPL(nfs_sb_active); 203 204 void nfs_sb_deactive(struct super_block *sb) 205 { 206 struct nfs_server *server = NFS_SB(sb); 207 208 if (atomic_dec_and_test(&server->active)) 209 deactivate_super(sb); 210 } 211 EXPORT_SYMBOL_GPL(nfs_sb_deactive); 212 213 static int __nfs_list_for_each_server(struct list_head *head, 214 int (*fn)(struct nfs_server *, void *), 215 void *data) 216 { 217 struct nfs_server *server, *last = NULL; 218 int ret = 0; 219 220 rcu_read_lock(); 221 list_for_each_entry_rcu(server, head, client_link) { 222 if (!(server->super && nfs_sb_active(server->super))) 223 continue; 224 rcu_read_unlock(); 225 if (last) 226 nfs_sb_deactive(last->super); 227 last = server; 228 ret = fn(server, data); 229 if (ret) 230 goto out; 231 rcu_read_lock(); 232 } 233 rcu_read_unlock(); 234 out: 235 if (last) 236 nfs_sb_deactive(last->super); 237 return ret; 238 } 239 240 int nfs_client_for_each_server(struct nfs_client *clp, 241 int (*fn)(struct nfs_server *, void *), 242 void *data) 243 { 244 return __nfs_list_for_each_server(&clp->cl_superblocks, fn, data); 245 } 246 EXPORT_SYMBOL_GPL(nfs_client_for_each_server); 247 248 /* 249 * Deliver file system statistics to userspace 250 */ 251 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf) 252 { 253 struct nfs_server *server = NFS_SB(dentry->d_sb); 254 unsigned char blockbits; 255 unsigned long blockres; 256 struct nfs_fh *fh = NFS_FH(d_inode(dentry)); 257 struct nfs_fsstat res; 258 int error = -ENOMEM; 259 260 res.fattr = nfs_alloc_fattr(); 261 if (res.fattr == NULL) 262 goto out_err; 263 264 error = server->nfs_client->rpc_ops->statfs(server, fh, &res); 265 if (unlikely(error == -ESTALE)) { 266 struct dentry *pd_dentry; 267 268 pd_dentry = dget_parent(dentry); 269 nfs_zap_caches(d_inode(pd_dentry)); 270 dput(pd_dentry); 271 } 272 nfs_free_fattr(res.fattr); 273 if (error < 0) 274 goto out_err; 275 276 buf->f_type = NFS_SUPER_MAGIC; 277 278 /* 279 * Current versions of glibc do not correctly handle the 280 * case where f_frsize != f_bsize. Eventually we want to 281 * report the value of wtmult in this field. 282 */ 283 buf->f_frsize = dentry->d_sb->s_blocksize; 284 285 /* 286 * On most *nix systems, f_blocks, f_bfree, and f_bavail 287 * are reported in units of f_frsize. Linux hasn't had 288 * an f_frsize field in its statfs struct until recently, 289 * thus historically Linux's sys_statfs reports these 290 * fields in units of f_bsize. 291 */ 292 buf->f_bsize = dentry->d_sb->s_blocksize; 293 blockbits = dentry->d_sb->s_blocksize_bits; 294 blockres = (1 << blockbits) - 1; 295 buf->f_blocks = (res.tbytes + blockres) >> blockbits; 296 buf->f_bfree = (res.fbytes + blockres) >> blockbits; 297 buf->f_bavail = (res.abytes + blockres) >> blockbits; 298 299 buf->f_files = res.tfiles; 300 buf->f_ffree = res.afiles; 301 302 buf->f_namelen = server->namelen; 303 304 return 0; 305 306 out_err: 307 dprintk("%s: statfs error = %d\n", __func__, -error); 308 return error; 309 } 310 EXPORT_SYMBOL_GPL(nfs_statfs); 311 312 /* 313 * Map the security flavour number to a name 314 */ 315 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour) 316 { 317 static const struct { 318 rpc_authflavor_t flavour; 319 const char *str; 320 } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = { 321 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */ 322 { RPC_AUTH_NULL, "null" }, 323 { RPC_AUTH_UNIX, "sys" }, 324 { RPC_AUTH_GSS_KRB5, "krb5" }, 325 { RPC_AUTH_GSS_KRB5I, "krb5i" }, 326 { RPC_AUTH_GSS_KRB5P, "krb5p" }, 327 { RPC_AUTH_GSS_LKEY, "lkey" }, 328 { RPC_AUTH_GSS_LKEYI, "lkeyi" }, 329 { RPC_AUTH_GSS_LKEYP, "lkeyp" }, 330 { RPC_AUTH_GSS_SPKM, "spkm" }, 331 { RPC_AUTH_GSS_SPKMI, "spkmi" }, 332 { RPC_AUTH_GSS_SPKMP, "spkmp" }, 333 { UINT_MAX, "unknown" } 334 }; 335 int i; 336 337 for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) { 338 if (sec_flavours[i].flavour == flavour) 339 break; 340 } 341 return sec_flavours[i].str; 342 } 343 344 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss, 345 int showdefaults) 346 { 347 struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address; 348 char *proto = NULL; 349 350 switch (sap->sa_family) { 351 case AF_INET: 352 switch (nfss->mountd_protocol) { 353 case IPPROTO_UDP: 354 proto = RPCBIND_NETID_UDP; 355 break; 356 case IPPROTO_TCP: 357 proto = RPCBIND_NETID_TCP; 358 break; 359 } 360 break; 361 case AF_INET6: 362 switch (nfss->mountd_protocol) { 363 case IPPROTO_UDP: 364 proto = RPCBIND_NETID_UDP6; 365 break; 366 case IPPROTO_TCP: 367 proto = RPCBIND_NETID_TCP6; 368 break; 369 } 370 break; 371 } 372 if (proto || showdefaults) 373 seq_printf(m, ",mountproto=%s", proto ?: "auto"); 374 } 375 376 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss, 377 int showdefaults) 378 { 379 struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address; 380 381 if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE) 382 return; 383 384 switch (sap->sa_family) { 385 case AF_INET: { 386 struct sockaddr_in *sin = (struct sockaddr_in *)sap; 387 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr); 388 break; 389 } 390 case AF_INET6: { 391 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap; 392 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr); 393 break; 394 } 395 default: 396 if (showdefaults) 397 seq_puts(m, ",mountaddr=unspecified"); 398 } 399 400 if (nfss->mountd_version || showdefaults) 401 seq_printf(m, ",mountvers=%u", nfss->mountd_version); 402 if ((nfss->mountd_port && 403 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) || 404 showdefaults) 405 seq_printf(m, ",mountport=%u", nfss->mountd_port); 406 407 nfs_show_mountd_netid(m, nfss, showdefaults); 408 } 409 410 #if IS_ENABLED(CONFIG_NFS_V4) 411 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss, 412 int showdefaults) 413 { 414 struct nfs_client *clp = nfss->nfs_client; 415 416 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr); 417 } 418 #else 419 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss, 420 int showdefaults) 421 { 422 } 423 #endif 424 425 static void nfs_show_nfs_version(struct seq_file *m, 426 unsigned int version, 427 unsigned int minorversion) 428 { 429 seq_printf(m, ",vers=%u", version); 430 if (version == 4) 431 seq_printf(m, ".%u", minorversion); 432 } 433 434 /* 435 * Describe the mount options in force on this server representation 436 */ 437 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, 438 int showdefaults) 439 { 440 static const struct proc_nfs_info { 441 int flag; 442 const char *str; 443 const char *nostr; 444 } nfs_info[] = { 445 { NFS_MOUNT_SOFT, ",soft", "" }, 446 { NFS_MOUNT_SOFTERR, ",softerr", "" }, 447 { NFS_MOUNT_SOFTREVAL, ",softreval", "" }, 448 { NFS_MOUNT_POSIX, ",posix", "" }, 449 { NFS_MOUNT_NOCTO, ",nocto", "" }, 450 { NFS_MOUNT_NOAC, ",noac", "" }, 451 { NFS_MOUNT_NONLM, ",nolock", "" }, 452 { NFS_MOUNT_NOACL, ",noacl", "" }, 453 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" }, 454 { NFS_MOUNT_UNSHARED, ",nosharecache", "" }, 455 { NFS_MOUNT_NORESVPORT, ",noresvport", "" }, 456 { 0, NULL, NULL } 457 }; 458 const struct proc_nfs_info *nfs_infop; 459 struct nfs_client *clp = nfss->nfs_client; 460 u32 version = clp->rpc_ops->version; 461 int local_flock, local_fcntl; 462 463 nfs_show_nfs_version(m, version, clp->cl_minorversion); 464 seq_printf(m, ",rsize=%u", nfss->rsize); 465 seq_printf(m, ",wsize=%u", nfss->wsize); 466 if (nfss->bsize != 0) 467 seq_printf(m, ",bsize=%u", nfss->bsize); 468 seq_printf(m, ",namlen=%u", nfss->namelen); 469 if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults) 470 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ); 471 if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults) 472 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ); 473 if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults) 474 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ); 475 if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults) 476 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ); 477 if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))) 478 seq_puts(m, ",hard"); 479 for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) { 480 if (nfss->flags & nfs_infop->flag) 481 seq_puts(m, nfs_infop->str); 482 else 483 seq_puts(m, nfs_infop->nostr); 484 } 485 rcu_read_lock(); 486 seq_printf(m, ",proto=%s", 487 rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID)); 488 rcu_read_unlock(); 489 if (clp->cl_nconnect > 0) 490 seq_printf(m, ",nconnect=%u", clp->cl_nconnect); 491 if (version == 4) { 492 if (clp->cl_max_connect > 1) 493 seq_printf(m, ",max_connect=%u", clp->cl_max_connect); 494 if (nfss->port != NFS_PORT) 495 seq_printf(m, ",port=%u", nfss->port); 496 } else 497 if (nfss->port) 498 seq_printf(m, ",port=%u", nfss->port); 499 500 seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ); 501 seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries); 502 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor)); 503 switch (clp->cl_xprtsec.policy) { 504 case RPC_XPRTSEC_TLS_ANON: 505 seq_puts(m, ",xprtsec=tls"); 506 break; 507 case RPC_XPRTSEC_TLS_X509: 508 seq_puts(m, ",xprtsec=mtls"); 509 break; 510 default: 511 break; 512 } 513 514 if (version != 4) 515 nfs_show_mountd_options(m, nfss, showdefaults); 516 else 517 nfs_show_nfsv4_options(m, nfss, showdefaults); 518 519 if (nfss->options & NFS_OPTION_FSCACHE) { 520 #ifdef CONFIG_NFS_FSCACHE 521 if (nfss->fscache_uniq) 522 seq_printf(m, ",fsc=%s", nfss->fscache_uniq); 523 else 524 seq_puts(m, ",fsc"); 525 #else 526 seq_puts(m, ",fsc"); 527 #endif 528 } 529 530 if (nfss->options & NFS_OPTION_MIGRATION) 531 seq_puts(m, ",migration"); 532 533 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) { 534 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE) 535 seq_puts(m, ",lookupcache=none"); 536 else 537 seq_puts(m, ",lookupcache=pos"); 538 } 539 540 local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK; 541 local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL; 542 543 if (!local_flock && !local_fcntl) 544 seq_puts(m, ",local_lock=none"); 545 else if (local_flock && local_fcntl) 546 seq_puts(m, ",local_lock=all"); 547 else if (local_flock) 548 seq_puts(m, ",local_lock=flock"); 549 else 550 seq_puts(m, ",local_lock=posix"); 551 552 if (nfss->flags & NFS_MOUNT_WRITE_EAGER) { 553 if (nfss->flags & NFS_MOUNT_WRITE_WAIT) 554 seq_puts(m, ",write=wait"); 555 else 556 seq_puts(m, ",write=eager"); 557 } 558 } 559 560 /* 561 * Describe the mount options on this VFS mountpoint 562 */ 563 int nfs_show_options(struct seq_file *m, struct dentry *root) 564 { 565 struct nfs_server *nfss = NFS_SB(root->d_sb); 566 567 nfs_show_mount_options(m, nfss, 0); 568 569 rcu_read_lock(); 570 seq_printf(m, ",addr=%s", 571 rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient, 572 RPC_DISPLAY_ADDR)); 573 rcu_read_unlock(); 574 575 return 0; 576 } 577 EXPORT_SYMBOL_GPL(nfs_show_options); 578 579 #if IS_ENABLED(CONFIG_NFS_V4) 580 static void show_lease(struct seq_file *m, struct nfs_server *server) 581 { 582 struct nfs_client *clp = server->nfs_client; 583 unsigned long expire; 584 585 seq_printf(m, ",lease_time=%ld", clp->cl_lease_time / HZ); 586 expire = clp->cl_last_renewal + clp->cl_lease_time; 587 seq_printf(m, ",lease_expired=%ld", 588 time_after(expire, jiffies) ? 0 : (jiffies - expire) / HZ); 589 } 590 #ifdef CONFIG_NFS_V4_1 591 static void show_sessions(struct seq_file *m, struct nfs_server *server) 592 { 593 if (nfs4_has_session(server->nfs_client)) 594 seq_puts(m, ",sessions"); 595 } 596 #else 597 static void show_sessions(struct seq_file *m, struct nfs_server *server) {} 598 #endif 599 #endif 600 601 #ifdef CONFIG_NFS_V4_1 602 static void show_pnfs(struct seq_file *m, struct nfs_server *server) 603 { 604 seq_printf(m, ",pnfs="); 605 if (server->pnfs_curr_ld) 606 seq_printf(m, "%s", server->pnfs_curr_ld->name); 607 else 608 seq_printf(m, "not configured"); 609 } 610 611 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss) 612 { 613 if (nfss->nfs_client && nfss->nfs_client->cl_implid) { 614 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid; 615 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s'," 616 "date='%llu,%u'", 617 impl_id->name, impl_id->domain, 618 impl_id->date.seconds, impl_id->date.nseconds); 619 } 620 } 621 #else 622 #if IS_ENABLED(CONFIG_NFS_V4) 623 static void show_pnfs(struct seq_file *m, struct nfs_server *server) 624 { 625 } 626 #endif 627 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss) 628 { 629 } 630 #endif 631 632 int nfs_show_devname(struct seq_file *m, struct dentry *root) 633 { 634 char *page = (char *) __get_free_page(GFP_KERNEL); 635 char *devname, *dummy; 636 int err = 0; 637 if (!page) 638 return -ENOMEM; 639 devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0); 640 if (IS_ERR(devname)) 641 err = PTR_ERR(devname); 642 else 643 seq_escape(m, devname, " \t\n\\"); 644 free_page((unsigned long)page); 645 return err; 646 } 647 EXPORT_SYMBOL_GPL(nfs_show_devname); 648 649 int nfs_show_path(struct seq_file *m, struct dentry *dentry) 650 { 651 seq_puts(m, "/"); 652 return 0; 653 } 654 EXPORT_SYMBOL_GPL(nfs_show_path); 655 656 /* 657 * Present statistical information for this VFS mountpoint 658 */ 659 int nfs_show_stats(struct seq_file *m, struct dentry *root) 660 { 661 int i, cpu; 662 struct nfs_server *nfss = NFS_SB(root->d_sb); 663 struct rpc_auth *auth = nfss->client->cl_auth; 664 struct nfs_iostats totals = { }; 665 666 seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS); 667 668 /* 669 * Display all mount option settings 670 */ 671 seq_puts(m, "\n\topts:\t"); 672 seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw"); 673 seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : ""); 674 seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : ""); 675 seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : ""); 676 nfs_show_mount_options(m, nfss, 1); 677 678 seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ); 679 680 show_implementation_id(m, nfss); 681 682 seq_puts(m, "\n\tcaps:\t"); 683 seq_printf(m, "caps=0x%x", nfss->caps); 684 seq_printf(m, ",wtmult=%u", nfss->wtmult); 685 seq_printf(m, ",dtsize=%u", nfss->dtsize); 686 seq_printf(m, ",bsize=%u", nfss->bsize); 687 seq_printf(m, ",namlen=%u", nfss->namelen); 688 689 #if IS_ENABLED(CONFIG_NFS_V4) 690 if (nfss->nfs_client->rpc_ops->version == 4) { 691 seq_puts(m, "\n\tnfsv4:\t"); 692 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]); 693 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]); 694 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]); 695 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask); 696 show_sessions(m, nfss); 697 show_pnfs(m, nfss); 698 show_lease(m, nfss); 699 } 700 #endif 701 702 /* 703 * Display security flavor in effect for this mount 704 */ 705 seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor); 706 if (auth->au_flavor) 707 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor); 708 709 /* 710 * Display superblock I/O counters 711 */ 712 for_each_possible_cpu(cpu) { 713 struct nfs_iostats *stats; 714 715 preempt_disable(); 716 stats = per_cpu_ptr(nfss->io_stats, cpu); 717 718 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 719 totals.events[i] += stats->events[i]; 720 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 721 totals.bytes[i] += stats->bytes[i]; 722 723 preempt_enable(); 724 } 725 726 seq_puts(m, "\n\tevents:\t"); 727 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 728 seq_printf(m, "%lu ", totals.events[i]); 729 seq_puts(m, "\n\tbytes:\t"); 730 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 731 seq_printf(m, "%Lu ", totals.bytes[i]); 732 seq_putc(m, '\n'); 733 734 rpc_clnt_show_stats(m, nfss->client); 735 736 return 0; 737 } 738 EXPORT_SYMBOL_GPL(nfs_show_stats); 739 740 /* 741 * Begin unmount by attempting to remove all automounted mountpoints we added 742 * in response to xdev traversals and referrals 743 */ 744 void nfs_umount_begin(struct super_block *sb) 745 { 746 struct nfs_server *server; 747 struct rpc_clnt *rpc; 748 749 server = NFS_SB(sb); 750 /* -EIO all pending I/O */ 751 rpc = server->client_acl; 752 if (!IS_ERR(rpc)) 753 rpc_killall_tasks(rpc); 754 rpc = server->client; 755 if (!IS_ERR(rpc)) 756 rpc_killall_tasks(rpc); 757 } 758 EXPORT_SYMBOL_GPL(nfs_umount_begin); 759 760 /* 761 * Return true if 'match' is in auth_info or auth_info is empty. 762 * Return false otherwise. 763 */ 764 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info, 765 rpc_authflavor_t match) 766 { 767 int i; 768 769 if (!auth_info->flavor_len) 770 return true; 771 772 for (i = 0; i < auth_info->flavor_len; i++) { 773 if (auth_info->flavors[i] == match) 774 return true; 775 } 776 return false; 777 } 778 EXPORT_SYMBOL_GPL(nfs_auth_info_match); 779 780 /* 781 * Ensure that a specified authtype in ctx->auth_info is supported by 782 * the server. Returns 0 and sets ctx->selected_flavor if it's ok, and 783 * -EACCES if not. 784 */ 785 static int nfs_verify_authflavors(struct nfs_fs_context *ctx, 786 rpc_authflavor_t *server_authlist, 787 unsigned int count) 788 { 789 rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR; 790 bool found_auth_null = false; 791 unsigned int i; 792 793 /* 794 * If the sec= mount option is used, the specified flavor or AUTH_NULL 795 * must be in the list returned by the server. 796 * 797 * AUTH_NULL has a special meaning when it's in the server list - it 798 * means that the server will ignore the rpc creds, so any flavor 799 * can be used but still use the sec= that was specified. 800 * 801 * Note also that the MNT procedure in MNTv1 does not return a list 802 * of supported security flavors. In this case, nfs_mount() fabricates 803 * a security flavor list containing just AUTH_NULL. 804 */ 805 for (i = 0; i < count; i++) { 806 flavor = server_authlist[i]; 807 808 if (nfs_auth_info_match(&ctx->auth_info, flavor)) 809 goto out; 810 811 if (flavor == RPC_AUTH_NULL) 812 found_auth_null = true; 813 } 814 815 if (found_auth_null) { 816 flavor = ctx->auth_info.flavors[0]; 817 goto out; 818 } 819 820 dfprintk(MOUNT, 821 "NFS: specified auth flavors not supported by server\n"); 822 return -EACCES; 823 824 out: 825 ctx->selected_flavor = flavor; 826 dfprintk(MOUNT, "NFS: using auth flavor %u\n", ctx->selected_flavor); 827 return 0; 828 } 829 830 /* 831 * Use the remote server's MOUNT service to request the NFS file handle 832 * corresponding to the provided path. 833 */ 834 static int nfs_request_mount(struct fs_context *fc, 835 struct nfs_fh *root_fh, 836 rpc_authflavor_t *server_authlist, 837 unsigned int *server_authlist_len) 838 { 839 struct nfs_fs_context *ctx = nfs_fc2context(fc); 840 struct nfs_mount_request request = { 841 .sap = &ctx->mount_server._address, 842 .dirpath = ctx->nfs_server.export_path, 843 .protocol = ctx->mount_server.protocol, 844 .fh = root_fh, 845 .noresvport = ctx->flags & NFS_MOUNT_NORESVPORT, 846 .auth_flav_len = server_authlist_len, 847 .auth_flavs = server_authlist, 848 .net = fc->net_ns, 849 }; 850 int status; 851 852 if (ctx->mount_server.version == 0) { 853 switch (ctx->version) { 854 default: 855 ctx->mount_server.version = NFS_MNT3_VERSION; 856 break; 857 case 2: 858 ctx->mount_server.version = NFS_MNT_VERSION; 859 } 860 } 861 request.version = ctx->mount_server.version; 862 863 if (ctx->mount_server.hostname) 864 request.hostname = ctx->mount_server.hostname; 865 else 866 request.hostname = ctx->nfs_server.hostname; 867 868 /* 869 * Construct the mount server's address. 870 */ 871 if (ctx->mount_server.address.sa_family == AF_UNSPEC) { 872 memcpy(request.sap, &ctx->nfs_server._address, 873 ctx->nfs_server.addrlen); 874 ctx->mount_server.addrlen = ctx->nfs_server.addrlen; 875 } 876 request.salen = ctx->mount_server.addrlen; 877 nfs_set_port(request.sap, &ctx->mount_server.port, 0); 878 879 /* 880 * Now ask the mount server to map our export path 881 * to a file handle. 882 */ 883 status = nfs_mount(&request, ctx->timeo, ctx->retrans); 884 if (status != 0) { 885 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n", 886 request.hostname, status); 887 return status; 888 } 889 890 return 0; 891 } 892 893 static struct nfs_server *nfs_try_mount_request(struct fs_context *fc) 894 { 895 struct nfs_fs_context *ctx = nfs_fc2context(fc); 896 int status; 897 unsigned int i; 898 bool tried_auth_unix = false; 899 bool auth_null_in_list = false; 900 struct nfs_server *server = ERR_PTR(-EACCES); 901 rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS]; 902 unsigned int authlist_len = ARRAY_SIZE(authlist); 903 904 /* make sure 'nolock'/'lock' override the 'local_lock' mount option */ 905 if (ctx->lock_status) { 906 if (ctx->lock_status == NFS_LOCK_NOLOCK) { 907 ctx->flags |= NFS_MOUNT_NONLM; 908 ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL); 909 } else { 910 ctx->flags &= ~NFS_MOUNT_NONLM; 911 ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL); 912 } 913 } 914 status = nfs_request_mount(fc, ctx->mntfh, authlist, &authlist_len); 915 if (status) 916 return ERR_PTR(status); 917 918 /* 919 * Was a sec= authflavor specified in the options? First, verify 920 * whether the server supports it, and then just try to use it if so. 921 */ 922 if (ctx->auth_info.flavor_len > 0) { 923 status = nfs_verify_authflavors(ctx, authlist, authlist_len); 924 dfprintk(MOUNT, "NFS: using auth flavor %u\n", 925 ctx->selected_flavor); 926 if (status) 927 return ERR_PTR(status); 928 return ctx->nfs_mod->rpc_ops->create_server(fc); 929 } 930 931 /* 932 * No sec= option was provided. RFC 2623, section 2.7 suggests we 933 * SHOULD prefer the flavor listed first. However, some servers list 934 * AUTH_NULL first. Avoid ever choosing AUTH_NULL. 935 */ 936 for (i = 0; i < authlist_len; ++i) { 937 rpc_authflavor_t flavor; 938 struct rpcsec_gss_info info; 939 940 flavor = authlist[i]; 941 switch (flavor) { 942 case RPC_AUTH_UNIX: 943 tried_auth_unix = true; 944 break; 945 case RPC_AUTH_NULL: 946 auth_null_in_list = true; 947 continue; 948 default: 949 if (rpcauth_get_gssinfo(flavor, &info) != 0) 950 continue; 951 break; 952 } 953 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor); 954 ctx->selected_flavor = flavor; 955 server = ctx->nfs_mod->rpc_ops->create_server(fc); 956 if (!IS_ERR(server)) 957 return server; 958 } 959 960 /* 961 * Nothing we tried so far worked. At this point, give up if we've 962 * already tried AUTH_UNIX or if the server's list doesn't contain 963 * AUTH_NULL 964 */ 965 if (tried_auth_unix || !auth_null_in_list) 966 return server; 967 968 /* Last chance! Try AUTH_UNIX */ 969 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX); 970 ctx->selected_flavor = RPC_AUTH_UNIX; 971 return ctx->nfs_mod->rpc_ops->create_server(fc); 972 } 973 974 int nfs_try_get_tree(struct fs_context *fc) 975 { 976 struct nfs_fs_context *ctx = nfs_fc2context(fc); 977 978 if (ctx->need_mount) 979 ctx->server = nfs_try_mount_request(fc); 980 else 981 ctx->server = ctx->nfs_mod->rpc_ops->create_server(fc); 982 983 return nfs_get_tree_common(fc); 984 } 985 EXPORT_SYMBOL_GPL(nfs_try_get_tree); 986 987 988 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \ 989 | NFS_MOUNT_SECURE \ 990 | NFS_MOUNT_TCP \ 991 | NFS_MOUNT_VER3 \ 992 | NFS_MOUNT_KERBEROS \ 993 | NFS_MOUNT_NONLM \ 994 | NFS_MOUNT_BROKEN_SUID \ 995 | NFS_MOUNT_STRICTLOCK \ 996 | NFS_MOUNT_LEGACY_INTERFACE) 997 998 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \ 999 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT)) 1000 1001 static int 1002 nfs_compare_remount_data(struct nfs_server *nfss, 1003 struct nfs_fs_context *ctx) 1004 { 1005 if ((ctx->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK || 1006 ctx->rsize != nfss->rsize || 1007 ctx->wsize != nfss->wsize || 1008 ctx->version != nfss->nfs_client->rpc_ops->version || 1009 ctx->minorversion != nfss->nfs_client->cl_minorversion || 1010 ctx->retrans != nfss->client->cl_timeout->to_retries || 1011 !nfs_auth_info_match(&ctx->auth_info, nfss->client->cl_auth->au_flavor) || 1012 ctx->acregmin != nfss->acregmin / HZ || 1013 ctx->acregmax != nfss->acregmax / HZ || 1014 ctx->acdirmin != nfss->acdirmin / HZ || 1015 ctx->acdirmax != nfss->acdirmax / HZ || 1016 ctx->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) || 1017 (ctx->options & NFS_OPTION_FSCACHE) != (nfss->options & NFS_OPTION_FSCACHE) || 1018 ctx->nfs_server.port != nfss->port || 1019 ctx->nfs_server.addrlen != nfss->nfs_client->cl_addrlen || 1020 !rpc_cmp_addr((struct sockaddr *)&ctx->nfs_server.address, 1021 (struct sockaddr *)&nfss->nfs_client->cl_addr)) 1022 return -EINVAL; 1023 1024 return 0; 1025 } 1026 1027 int nfs_reconfigure(struct fs_context *fc) 1028 { 1029 struct nfs_fs_context *ctx = nfs_fc2context(fc); 1030 struct super_block *sb = fc->root->d_sb; 1031 struct nfs_server *nfss = sb->s_fs_info; 1032 int ret; 1033 1034 sync_filesystem(sb); 1035 1036 /* 1037 * Userspace mount programs that send binary options generally send 1038 * them populated with default values. We have no way to know which 1039 * ones were explicitly specified. Fall back to legacy behavior and 1040 * just return success. 1041 */ 1042 if (ctx->skip_reconfig_option_check) 1043 return 0; 1044 1045 /* 1046 * noac is a special case. It implies -o sync, but that's not 1047 * necessarily reflected in the mtab options. reconfigure_super 1048 * will clear SB_SYNCHRONOUS if -o sync wasn't specified in the 1049 * remount options, so we have to explicitly reset it. 1050 */ 1051 if (ctx->flags & NFS_MOUNT_NOAC) { 1052 fc->sb_flags |= SB_SYNCHRONOUS; 1053 fc->sb_flags_mask |= SB_SYNCHRONOUS; 1054 } 1055 1056 /* compare new mount options with old ones */ 1057 ret = nfs_compare_remount_data(nfss, ctx); 1058 if (ret) 1059 return ret; 1060 1061 return nfs_probe_server(nfss, NFS_FH(d_inode(fc->root))); 1062 } 1063 EXPORT_SYMBOL_GPL(nfs_reconfigure); 1064 1065 /* 1066 * Finish setting up an NFS superblock 1067 */ 1068 static void nfs_fill_super(struct super_block *sb, struct nfs_fs_context *ctx) 1069 { 1070 struct nfs_server *server = NFS_SB(sb); 1071 1072 sb->s_blocksize_bits = 0; 1073 sb->s_blocksize = 0; 1074 sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr; 1075 sb->s_op = server->nfs_client->cl_nfs_mod->sops; 1076 if (ctx->bsize) 1077 sb->s_blocksize = nfs_block_size(ctx->bsize, &sb->s_blocksize_bits); 1078 1079 switch (server->nfs_client->rpc_ops->version) { 1080 case 2: 1081 sb->s_time_gran = 1000; 1082 sb->s_time_min = 0; 1083 sb->s_time_max = U32_MAX; 1084 break; 1085 case 3: 1086 /* 1087 * The VFS shouldn't apply the umask to mode bits. 1088 * We will do so ourselves when necessary. 1089 */ 1090 sb->s_flags |= SB_POSIXACL; 1091 sb->s_time_gran = 1; 1092 sb->s_time_min = 0; 1093 sb->s_time_max = U32_MAX; 1094 sb->s_export_op = &nfs_export_ops; 1095 break; 1096 case 4: 1097 sb->s_iflags |= SB_I_NOUMASK; 1098 sb->s_time_gran = 1; 1099 sb->s_time_min = S64_MIN; 1100 sb->s_time_max = S64_MAX; 1101 if (server->caps & NFS_CAP_ATOMIC_OPEN_V1) 1102 sb->s_export_op = &nfs_export_ops; 1103 break; 1104 } 1105 1106 sb->s_magic = NFS_SUPER_MAGIC; 1107 1108 /* We probably want something more informative here */ 1109 snprintf(sb->s_id, sizeof(sb->s_id), 1110 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev)); 1111 1112 if (sb->s_blocksize == 0) 1113 sb->s_blocksize = nfs_block_bits(server->wsize, 1114 &sb->s_blocksize_bits); 1115 1116 nfs_super_set_maxbytes(sb, server->maxfilesize); 1117 nfs_sysfs_move_server_to_sb(sb); 1118 server->has_sec_mnt_opts = ctx->has_sec_mnt_opts; 1119 } 1120 1121 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, 1122 const struct fs_context *fc) 1123 { 1124 const struct nfs_server *a = s->s_fs_info; 1125 const struct rpc_clnt *clnt_a = a->client; 1126 const struct rpc_clnt *clnt_b = b->client; 1127 1128 if ((s->s_flags & NFS_SB_MASK) != (fc->sb_flags & NFS_SB_MASK)) 1129 goto Ebusy; 1130 if (a->nfs_client != b->nfs_client) 1131 goto Ebusy; 1132 if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK) 1133 goto Ebusy; 1134 if (a->wsize != b->wsize) 1135 goto Ebusy; 1136 if (a->rsize != b->rsize) 1137 goto Ebusy; 1138 if (a->acregmin != b->acregmin) 1139 goto Ebusy; 1140 if (a->acregmax != b->acregmax) 1141 goto Ebusy; 1142 if (a->acdirmin != b->acdirmin) 1143 goto Ebusy; 1144 if (a->acdirmax != b->acdirmax) 1145 goto Ebusy; 1146 if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor) 1147 goto Ebusy; 1148 return 1; 1149 Ebusy: 1150 return 0; 1151 } 1152 1153 static int nfs_set_super(struct super_block *s, struct fs_context *fc) 1154 { 1155 struct nfs_server *server = fc->s_fs_info; 1156 int ret; 1157 1158 s->s_d_op = server->nfs_client->rpc_ops->dentry_ops; 1159 ret = set_anon_super(s, server); 1160 if (ret == 0) 1161 server->s_dev = s->s_dev; 1162 return ret; 1163 } 1164 1165 static int nfs_compare_super_address(struct nfs_server *server1, 1166 struct nfs_server *server2) 1167 { 1168 struct sockaddr *sap1, *sap2; 1169 struct rpc_xprt *xprt1 = server1->client->cl_xprt; 1170 struct rpc_xprt *xprt2 = server2->client->cl_xprt; 1171 1172 if (!net_eq(xprt1->xprt_net, xprt2->xprt_net)) 1173 return 0; 1174 1175 sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr; 1176 sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr; 1177 1178 if (sap1->sa_family != sap2->sa_family) 1179 return 0; 1180 1181 switch (sap1->sa_family) { 1182 case AF_INET: { 1183 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1; 1184 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2; 1185 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr) 1186 return 0; 1187 if (sin1->sin_port != sin2->sin_port) 1188 return 0; 1189 break; 1190 } 1191 case AF_INET6: { 1192 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1; 1193 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2; 1194 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr)) 1195 return 0; 1196 if (sin1->sin6_port != sin2->sin6_port) 1197 return 0; 1198 break; 1199 } 1200 default: 1201 return 0; 1202 } 1203 1204 return 1; 1205 } 1206 1207 static int nfs_compare_userns(const struct nfs_server *old, 1208 const struct nfs_server *new) 1209 { 1210 const struct user_namespace *oldns = &init_user_ns; 1211 const struct user_namespace *newns = &init_user_ns; 1212 1213 if (old->client && old->client->cl_cred) 1214 oldns = old->client->cl_cred->user_ns; 1215 if (new->client && new->client->cl_cred) 1216 newns = new->client->cl_cred->user_ns; 1217 if (oldns != newns) 1218 return 0; 1219 return 1; 1220 } 1221 1222 static int nfs_compare_super(struct super_block *sb, struct fs_context *fc) 1223 { 1224 struct nfs_server *server = fc->s_fs_info, *old = NFS_SB(sb); 1225 1226 if (!nfs_compare_super_address(old, server)) 1227 return 0; 1228 /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */ 1229 if (old->flags & NFS_MOUNT_UNSHARED) 1230 return 0; 1231 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0) 1232 return 0; 1233 if (!nfs_compare_userns(old, server)) 1234 return 0; 1235 if ((old->has_sec_mnt_opts || fc->security) && 1236 security_sb_mnt_opts_compat(sb, fc->security)) 1237 return 0; 1238 return nfs_compare_mount_options(sb, server, fc); 1239 } 1240 1241 #ifdef CONFIG_NFS_FSCACHE 1242 static int nfs_get_cache_cookie(struct super_block *sb, 1243 struct nfs_fs_context *ctx) 1244 { 1245 struct nfs_server *nfss = NFS_SB(sb); 1246 char *uniq = NULL; 1247 int ulen = 0; 1248 1249 nfss->fscache = NULL; 1250 1251 if (!ctx) 1252 return 0; 1253 1254 if (ctx->clone_data.sb) { 1255 struct nfs_server *mnt_s = NFS_SB(ctx->clone_data.sb); 1256 if (!(mnt_s->options & NFS_OPTION_FSCACHE)) 1257 return 0; 1258 if (mnt_s->fscache_uniq) { 1259 uniq = mnt_s->fscache_uniq; 1260 ulen = strlen(uniq); 1261 } 1262 } else { 1263 if (!(ctx->options & NFS_OPTION_FSCACHE)) 1264 return 0; 1265 if (ctx->fscache_uniq) { 1266 uniq = ctx->fscache_uniq; 1267 ulen = strlen(ctx->fscache_uniq); 1268 } 1269 } 1270 1271 return nfs_fscache_get_super_cookie(sb, uniq, ulen); 1272 } 1273 #else 1274 static int nfs_get_cache_cookie(struct super_block *sb, 1275 struct nfs_fs_context *ctx) 1276 { 1277 return 0; 1278 } 1279 #endif 1280 1281 int nfs_get_tree_common(struct fs_context *fc) 1282 { 1283 struct nfs_fs_context *ctx = nfs_fc2context(fc); 1284 struct super_block *s; 1285 int (*compare_super)(struct super_block *, struct fs_context *) = nfs_compare_super; 1286 struct nfs_server *server = ctx->server; 1287 int error; 1288 1289 ctx->server = NULL; 1290 if (IS_ERR(server)) 1291 return PTR_ERR(server); 1292 1293 if (server->flags & NFS_MOUNT_UNSHARED) 1294 compare_super = NULL; 1295 1296 /* -o noac implies -o sync */ 1297 if (server->flags & NFS_MOUNT_NOAC) 1298 fc->sb_flags |= SB_SYNCHRONOUS; 1299 1300 if (ctx->clone_data.sb) 1301 if (ctx->clone_data.sb->s_flags & SB_SYNCHRONOUS) 1302 fc->sb_flags |= SB_SYNCHRONOUS; 1303 1304 /* Get a superblock - note that we may end up sharing one that already exists */ 1305 fc->s_fs_info = server; 1306 s = sget_fc(fc, compare_super, nfs_set_super); 1307 fc->s_fs_info = NULL; 1308 if (IS_ERR(s)) { 1309 error = PTR_ERR(s); 1310 nfs_errorf(fc, "NFS: Couldn't get superblock"); 1311 goto out_err_nosb; 1312 } 1313 1314 if (s->s_fs_info != server) { 1315 nfs_free_server(server); 1316 server = NULL; 1317 } else { 1318 error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev), 1319 MINOR(server->s_dev)); 1320 if (error) 1321 goto error_splat_super; 1322 s->s_bdi->io_pages = server->rpages; 1323 server->super = s; 1324 } 1325 1326 if (!s->s_root) { 1327 unsigned bsize = ctx->clone_data.inherited_bsize; 1328 /* initial superblock/root creation */ 1329 nfs_fill_super(s, ctx); 1330 if (bsize) { 1331 s->s_blocksize_bits = bsize; 1332 s->s_blocksize = 1U << bsize; 1333 } 1334 error = nfs_get_cache_cookie(s, ctx); 1335 if (error < 0) 1336 goto error_splat_super; 1337 } 1338 1339 error = nfs_get_root(s, fc); 1340 if (error < 0) { 1341 nfs_errorf(fc, "NFS: Couldn't get root dentry"); 1342 goto error_splat_super; 1343 } 1344 1345 s->s_flags |= SB_ACTIVE; 1346 error = 0; 1347 1348 out: 1349 return error; 1350 1351 out_err_nosb: 1352 nfs_free_server(server); 1353 goto out; 1354 error_splat_super: 1355 deactivate_locked_super(s); 1356 goto out; 1357 } 1358 1359 /* 1360 * Destroy an NFS superblock 1361 */ 1362 void nfs_kill_super(struct super_block *s) 1363 { 1364 struct nfs_server *server = NFS_SB(s); 1365 1366 nfs_sysfs_move_sb_to_server(server); 1367 kill_anon_super(s); 1368 1369 nfs_fscache_release_super_cookie(s); 1370 1371 nfs_free_server(server); 1372 } 1373 EXPORT_SYMBOL_GPL(nfs_kill_super); 1374 1375 #if IS_ENABLED(CONFIG_NFS_V4) 1376 1377 /* 1378 * NFS v4 module parameters need to stay in the 1379 * NFS client for backwards compatibility 1380 */ 1381 unsigned int nfs_callback_set_tcpport; 1382 unsigned short nfs_callback_nr_threads; 1383 /* Default cache timeout is 10 minutes */ 1384 unsigned int nfs_idmap_cache_timeout = 600; 1385 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */ 1386 bool nfs4_disable_idmapping = true; 1387 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE; 1388 unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE; 1389 unsigned short send_implementation_id = 1; 1390 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = ""; 1391 bool recover_lost_locks = false; 1392 short nfs_delay_retrans = -1; 1393 1394 EXPORT_SYMBOL_GPL(nfs_callback_nr_threads); 1395 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport); 1396 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout); 1397 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping); 1398 EXPORT_SYMBOL_GPL(max_session_slots); 1399 EXPORT_SYMBOL_GPL(max_session_cb_slots); 1400 EXPORT_SYMBOL_GPL(send_implementation_id); 1401 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier); 1402 EXPORT_SYMBOL_GPL(recover_lost_locks); 1403 EXPORT_SYMBOL_GPL(nfs_delay_retrans); 1404 1405 #define NFS_CALLBACK_MAXPORTNR (65535U) 1406 1407 static int param_set_portnr(const char *val, const struct kernel_param *kp) 1408 { 1409 unsigned long num; 1410 int ret; 1411 1412 if (!val) 1413 return -EINVAL; 1414 ret = kstrtoul(val, 0, &num); 1415 if (ret || num > NFS_CALLBACK_MAXPORTNR) 1416 return -EINVAL; 1417 *((unsigned int *)kp->arg) = num; 1418 return 0; 1419 } 1420 static const struct kernel_param_ops param_ops_portnr = { 1421 .set = param_set_portnr, 1422 .get = param_get_uint, 1423 }; 1424 #define param_check_portnr(name, p) __param_check(name, p, unsigned int) 1425 1426 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644); 1427 module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644); 1428 MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be " 1429 "assigned to the NFSv4 callback channels."); 1430 module_param(nfs_idmap_cache_timeout, int, 0644); 1431 module_param(nfs4_disable_idmapping, bool, 0644); 1432 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier, 1433 NFS4_CLIENT_ID_UNIQ_LEN, 0600); 1434 MODULE_PARM_DESC(nfs4_disable_idmapping, 1435 "Turn off NFSv4 idmapping when using 'sec=sys'"); 1436 module_param(max_session_slots, ushort, 0644); 1437 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 " 1438 "requests the client will negotiate"); 1439 module_param(max_session_cb_slots, ushort, 0644); 1440 MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 " 1441 "callbacks the client will process for a given server"); 1442 module_param(send_implementation_id, ushort, 0644); 1443 MODULE_PARM_DESC(send_implementation_id, 1444 "Send implementation ID with NFSv4.1 exchange_id"); 1445 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string"); 1446 1447 module_param(recover_lost_locks, bool, 0644); 1448 MODULE_PARM_DESC(recover_lost_locks, 1449 "If the server reports that a lock might be lost, " 1450 "try to recover it risking data corruption."); 1451 1452 module_param_named(delay_retrans, nfs_delay_retrans, short, 0644); 1453 MODULE_PARM_DESC(delay_retrans, 1454 "Unless negative, specifies the number of times the NFSv4 " 1455 "client retries a request before returning an EAGAIN error, " 1456 "after a reply of NFS4ERR_DELAY from the server."); 1457 #endif /* CONFIG_NFS_V4 */ 1458