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/sched.h> 51 #include <linux/slab.h> 52 #include <net/ipv6.h> 53 #include <linux/netdevice.h> 54 #include <linux/nfs_xdr.h> 55 #include <linux/magic.h> 56 #include <linux/parser.h> 57 #include <linux/nsproxy.h> 58 #include <linux/rcupdate.h> 59 60 #include <linux/uaccess.h> 61 #include <linux/nfs_ssc.h> 62 63 #include <uapi/linux/tls.h> 64 65 #include "nfs4_fs.h" 66 #include "callback.h" 67 #include "delegation.h" 68 #include "iostat.h" 69 #include "internal.h" 70 #include "fscache.h" 71 #include "nfs4session.h" 72 #include "pnfs.h" 73 #include "nfs.h" 74 #include "netns.h" 75 #include "sysfs.h" 76 #include "nfs4idmap.h" 77 78 #define NFSDBG_FACILITY NFSDBG_VFS 79 80 const struct super_operations nfs_sops = { 81 .alloc_inode = nfs_alloc_inode, 82 .free_inode = nfs_free_inode, 83 .write_inode = nfs_write_inode, 84 .drop_inode = nfs_drop_inode, 85 .statfs = nfs_statfs, 86 .evict_inode = nfs_evict_inode, 87 .umount_begin = nfs_umount_begin, 88 .show_options = nfs_show_options, 89 .show_devname = nfs_show_devname, 90 .show_path = nfs_show_path, 91 .show_stats = nfs_show_stats, 92 }; 93 EXPORT_SYMBOL_GPL(nfs_sops); 94 95 #ifdef CONFIG_NFS_V4_2 96 static const struct nfs_ssc_client_ops nfs_ssc_clnt_ops_tbl = { 97 .sco_sb_deactive = nfs_sb_deactive, 98 }; 99 #endif 100 101 #if IS_ENABLED(CONFIG_NFS_V4) 102 static int __init register_nfs4_fs(void) 103 { 104 return register_filesystem(&nfs4_fs_type); 105 } 106 107 static void unregister_nfs4_fs(void) 108 { 109 unregister_filesystem(&nfs4_fs_type); 110 } 111 #else 112 static int __init register_nfs4_fs(void) 113 { 114 return 0; 115 } 116 117 static void unregister_nfs4_fs(void) 118 { 119 } 120 #endif 121 122 #ifdef CONFIG_NFS_V4_2 123 static void nfs_ssc_register_ops(void) 124 { 125 nfs_ssc_register(&nfs_ssc_clnt_ops_tbl); 126 } 127 128 static void nfs_ssc_unregister_ops(void) 129 { 130 nfs_ssc_unregister(&nfs_ssc_clnt_ops_tbl); 131 } 132 #endif /* CONFIG_NFS_V4_2 */ 133 134 static struct shrinker *acl_shrinker; 135 136 /* 137 * Register the NFS filesystems 138 */ 139 int __init register_nfs_fs(void) 140 { 141 int ret; 142 143 ret = register_filesystem(&nfs_fs_type); 144 if (ret < 0) 145 goto error_0; 146 147 ret = register_nfs4_fs(); 148 if (ret < 0) 149 goto error_1; 150 151 ret = nfs_register_sysctl(); 152 if (ret < 0) 153 goto error_2; 154 155 acl_shrinker = shrinker_alloc(0, "nfs-acl"); 156 if (!acl_shrinker) { 157 ret = -ENOMEM; 158 goto error_3; 159 } 160 161 acl_shrinker->count_objects = nfs_access_cache_count; 162 acl_shrinker->scan_objects = nfs_access_cache_scan; 163 164 shrinker_register(acl_shrinker); 165 166 #ifdef CONFIG_NFS_V4_2 167 nfs_ssc_register_ops(); 168 #endif 169 return 0; 170 error_3: 171 nfs_unregister_sysctl(); 172 error_2: 173 unregister_nfs4_fs(); 174 error_1: 175 unregister_filesystem(&nfs_fs_type); 176 error_0: 177 return ret; 178 } 179 180 /* 181 * Unregister the NFS filesystems 182 */ 183 void __exit unregister_nfs_fs(void) 184 { 185 shrinker_free(acl_shrinker); 186 nfs_unregister_sysctl(); 187 unregister_nfs4_fs(); 188 #ifdef CONFIG_NFS_V4_2 189 nfs_ssc_unregister_ops(); 190 #endif 191 unregister_filesystem(&nfs_fs_type); 192 } 193 194 bool nfs_sb_active(struct super_block *sb) 195 { 196 struct nfs_server *server = NFS_SB(sb); 197 198 if (!atomic_inc_not_zero(&sb->s_active)) 199 return false; 200 if (atomic_inc_return(&server->active) != 1) 201 atomic_dec(&sb->s_active); 202 return true; 203 } 204 EXPORT_SYMBOL_GPL(nfs_sb_active); 205 206 void nfs_sb_deactive(struct super_block *sb) 207 { 208 struct nfs_server *server = NFS_SB(sb); 209 210 if (atomic_dec_and_test(&server->active)) 211 deactivate_super(sb); 212 } 213 EXPORT_SYMBOL_GPL(nfs_sb_deactive); 214 215 int nfs_client_for_each_server(struct nfs_client *clp, 216 int (*fn)(struct nfs_server *server, void *data), void *data) 217 { 218 struct nfs_server *server, *last = NULL; 219 int ret = 0; 220 221 rcu_read_lock(); 222 list_for_each_entry_rcu(server, &clp->cl_superblocks, client_link) { 223 if (!(server->super && nfs_sb_active(server->super))) 224 continue; 225 rcu_read_unlock(); 226 if (last) 227 nfs_sb_deactive(last->super); 228 last = server; 229 ret = fn(server, data); 230 if (ret) 231 goto out; 232 cond_resched(); 233 rcu_read_lock(); 234 } 235 rcu_read_unlock(); 236 out: 237 if (last) 238 nfs_sb_deactive(last->super); 239 return ret; 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_FORCE_RDIRPLUS, ",rdirplus=force", "" }, 450 { NFS_MOUNT_UNSHARED, ",nosharecache", "" }, 451 { NFS_MOUNT_NORESVPORT, ",noresvport", "" }, 452 { NFS_MOUNT_NETUNREACH_FATAL, 453 ",fatal_neterrors=ENETDOWN:ENETUNREACH", 454 ",fatal_neterrors=none" }, 455 { 0, NULL, NULL } 456 }; 457 const struct proc_nfs_info *nfs_infop; 458 struct nfs_client *clp = nfss->nfs_client; 459 u32 version = clp->rpc_ops->version; 460 int local_flock, local_fcntl; 461 462 nfs_show_nfs_version(m, version, clp->cl_minorversion); 463 seq_printf(m, ",rsize=%u", nfss->rsize); 464 seq_printf(m, ",wsize=%u", nfss->wsize); 465 if (nfss->bsize != 0) 466 seq_printf(m, ",bsize=%u", nfss->bsize); 467 seq_printf(m, ",namlen=%u", nfss->namelen); 468 if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults) 469 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ); 470 if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults) 471 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ); 472 if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults) 473 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ); 474 if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults) 475 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ); 476 if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))) 477 seq_puts(m, ",hard"); 478 for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) { 479 if (nfss->flags & nfs_infop->flag) 480 seq_puts(m, nfs_infop->str); 481 else 482 seq_puts(m, nfs_infop->nostr); 483 } 484 rcu_read_lock(); 485 seq_printf(m, ",proto=%s", 486 rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID)); 487 rcu_read_unlock(); 488 if (clp->cl_nconnect > 0) 489 seq_printf(m, ",nconnect=%u", clp->cl_nconnect); 490 if (version == 4) { 491 if (clp->cl_max_connect > 1) 492 seq_printf(m, ",max_connect=%u", clp->cl_max_connect); 493 if (nfss->port != NFS_PORT) 494 seq_printf(m, ",port=%u", nfss->port); 495 } else 496 if (nfss->port) 497 seq_printf(m, ",port=%u", nfss->port); 498 499 seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ); 500 seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries); 501 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor)); 502 switch (clp->cl_xprtsec.policy) { 503 case RPC_XPRTSEC_TLS_ANON: 504 seq_puts(m, ",xprtsec=tls"); 505 break; 506 case RPC_XPRTSEC_TLS_X509: 507 seq_puts(m, ",xprtsec=mtls"); 508 break; 509 default: 510 break; 511 } 512 if (clp->cl_xprtsec.cert_serial) 513 seq_puts(m, ",cert_serial=<redacted>"); 514 if (clp->cl_xprtsec.privkey_serial) 515 seq_puts(m, ",privkey_serial=<redacted>"); 516 517 if (version != 4) 518 nfs_show_mountd_options(m, nfss, showdefaults); 519 else 520 nfs_show_nfsv4_options(m, nfss, showdefaults); 521 522 if (nfss->options & NFS_OPTION_FSCACHE) { 523 #ifdef CONFIG_NFS_FSCACHE 524 if (nfss->fscache_uniq) 525 seq_printf(m, ",fsc=%s", nfss->fscache_uniq); 526 else 527 seq_puts(m, ",fsc"); 528 #else 529 seq_puts(m, ",fsc"); 530 #endif 531 } 532 533 if (nfss->options & NFS_OPTION_MIGRATION) 534 seq_puts(m, ",migration"); 535 536 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) { 537 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE) 538 seq_puts(m, ",lookupcache=none"); 539 else 540 seq_puts(m, ",lookupcache=pos"); 541 } 542 543 local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK; 544 local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL; 545 546 if (!local_flock && !local_fcntl) 547 seq_puts(m, ",local_lock=none"); 548 else if (local_flock && local_fcntl) 549 seq_puts(m, ",local_lock=all"); 550 else if (local_flock) 551 seq_puts(m, ",local_lock=flock"); 552 else 553 seq_puts(m, ",local_lock=posix"); 554 555 if (nfss->flags & NFS_MOUNT_NO_ALIGNWRITE) 556 seq_puts(m, ",noalignwrite"); 557 558 if (nfss->flags & NFS_MOUNT_WRITE_EAGER) { 559 if (nfss->flags & NFS_MOUNT_WRITE_WAIT) 560 seq_puts(m, ",write=wait"); 561 else 562 seq_puts(m, ",write=eager"); 563 } 564 } 565 566 /* 567 * Describe the mount options on this VFS mountpoint 568 */ 569 int nfs_show_options(struct seq_file *m, struct dentry *root) 570 { 571 struct nfs_server *nfss = NFS_SB(root->d_sb); 572 573 nfs_show_mount_options(m, nfss, 0); 574 575 rcu_read_lock(); 576 seq_printf(m, ",addr=%s", 577 rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient, 578 RPC_DISPLAY_ADDR)); 579 rcu_read_unlock(); 580 581 return 0; 582 } 583 EXPORT_SYMBOL_GPL(nfs_show_options); 584 585 #if IS_ENABLED(CONFIG_NFS_V4) 586 static void show_lease(struct seq_file *m, struct nfs_server *server) 587 { 588 struct nfs_client *clp = server->nfs_client; 589 unsigned long expire; 590 591 seq_printf(m, ",lease_time=%ld", clp->cl_lease_time / HZ); 592 expire = clp->cl_last_renewal + clp->cl_lease_time; 593 seq_printf(m, ",lease_expired=%ld", 594 time_after(expire, jiffies) ? 0 : (jiffies - expire) / HZ); 595 } 596 597 static void show_sessions(struct seq_file *m, struct nfs_server *server) 598 { 599 if (nfs4_has_session(server->nfs_client)) 600 seq_puts(m, ",sessions"); 601 } 602 603 static void show_pnfs(struct seq_file *m, struct nfs_server *server) 604 { 605 seq_printf(m, ",pnfs="); 606 if (server->pnfs_curr_ld) 607 seq_printf(m, "%s", server->pnfs_curr_ld->name); 608 else 609 seq_printf(m, "not configured"); 610 } 611 612 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss) 613 { 614 if (nfss->nfs_client && nfss->nfs_client->cl_implid) { 615 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid; 616 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s'," 617 "date='%llu,%u'", 618 impl_id->name, impl_id->domain, 619 impl_id->date.seconds, impl_id->date.nseconds); 620 } 621 } 622 #else /* CONFIG_NFS_V4 */ 623 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss) 624 { 625 } 626 #endif /* CONFIG_NFS_V4 */ 627 628 int nfs_show_devname(struct seq_file *m, struct dentry *root) 629 { 630 char *page = kmalloc(PAGE_SIZE, GFP_KERNEL); 631 char *devname, *dummy; 632 int err = 0; 633 if (!page) 634 return -ENOMEM; 635 devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0); 636 if (IS_ERR(devname)) 637 err = PTR_ERR(devname); 638 else 639 seq_escape(m, devname, " \t\n\\"); 640 kfree(page); 641 return err; 642 } 643 EXPORT_SYMBOL_GPL(nfs_show_devname); 644 645 int nfs_show_path(struct seq_file *m, struct dentry *dentry) 646 { 647 seq_puts(m, "/"); 648 return 0; 649 } 650 EXPORT_SYMBOL_GPL(nfs_show_path); 651 652 /* 653 * Present statistical information for this VFS mountpoint 654 */ 655 int nfs_show_stats(struct seq_file *m, struct dentry *root) 656 { 657 int i, cpu; 658 struct nfs_server *nfss = NFS_SB(root->d_sb); 659 struct rpc_auth *auth = nfss->client->cl_auth; 660 struct nfs_iostats totals = { }; 661 662 seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS); 663 664 /* 665 * Display all mount option settings 666 */ 667 seq_puts(m, "\n\topts:\t"); 668 seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw"); 669 seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : ""); 670 seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : ""); 671 seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : ""); 672 nfs_show_mount_options(m, nfss, 1); 673 674 seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ); 675 676 show_implementation_id(m, nfss); 677 678 seq_puts(m, "\n\tcaps:\t"); 679 seq_printf(m, "caps=0x%x", nfss->caps); 680 seq_printf(m, ",wtmult=%u", nfss->wtmult); 681 seq_printf(m, ",dtsize=%u", nfss->dtsize); 682 seq_printf(m, ",bsize=%u", nfss->bsize); 683 seq_printf(m, ",namlen=%u", nfss->namelen); 684 685 #if IS_ENABLED(CONFIG_NFS_V4) 686 if (nfss->nfs_client->rpc_ops->version == 4) { 687 seq_puts(m, "\n\tnfsv4:\t"); 688 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]); 689 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]); 690 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]); 691 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask); 692 show_sessions(m, nfss); 693 show_pnfs(m, nfss); 694 show_lease(m, nfss); 695 } 696 #endif 697 698 /* 699 * Display security flavor in effect for this mount 700 */ 701 seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor); 702 if (auth->au_flavor) 703 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor); 704 705 /* 706 * Display superblock I/O counters 707 */ 708 for_each_possible_cpu(cpu) { 709 struct nfs_iostats *stats; 710 711 preempt_disable(); 712 stats = per_cpu_ptr(nfss->io_stats, cpu); 713 714 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 715 totals.events[i] += stats->events[i]; 716 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 717 totals.bytes[i] += stats->bytes[i]; 718 719 preempt_enable(); 720 } 721 722 seq_puts(m, "\n\tevents:\t"); 723 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 724 seq_printf(m, "%lu ", totals.events[i]); 725 seq_puts(m, "\n\tbytes:\t"); 726 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 727 seq_printf(m, "%Lu ", totals.bytes[i]); 728 seq_putc(m, '\n'); 729 730 rpc_clnt_show_stats(m, nfss->client); 731 732 return 0; 733 } 734 EXPORT_SYMBOL_GPL(nfs_show_stats); 735 736 /* 737 * Begin unmount by attempting to remove all automounted mountpoints we added 738 * in response to xdev traversals and referrals 739 */ 740 void nfs_umount_begin(struct super_block *sb) 741 { 742 struct nfs_server *server; 743 struct rpc_clnt *rpc; 744 745 server = NFS_SB(sb); 746 /* -EIO all pending I/O */ 747 rpc = server->client_acl; 748 if (!IS_ERR(rpc)) 749 rpc_killall_tasks(rpc); 750 rpc = server->client; 751 if (!IS_ERR(rpc)) 752 rpc_killall_tasks(rpc); 753 } 754 EXPORT_SYMBOL_GPL(nfs_umount_begin); 755 756 /* 757 * Return true if 'match' is in auth_info or auth_info is empty. 758 * Return false otherwise. 759 */ 760 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info, 761 rpc_authflavor_t match) 762 { 763 int i; 764 765 if (!auth_info->flavor_len) 766 return true; 767 768 for (i = 0; i < auth_info->flavor_len; i++) { 769 if (auth_info->flavors[i] == match) 770 return true; 771 } 772 return false; 773 } 774 EXPORT_SYMBOL_GPL(nfs_auth_info_match); 775 776 /* 777 * Ensure that a specified authtype in ctx->auth_info is supported by 778 * the server. Returns 0 and sets ctx->selected_flavor if it's ok, and 779 * -EACCES if not. 780 */ 781 static int nfs_verify_authflavors(struct nfs_fs_context *ctx, 782 rpc_authflavor_t *server_authlist, 783 unsigned int count) 784 { 785 rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR; 786 bool found_auth_null = false; 787 unsigned int i; 788 789 /* 790 * If the sec= mount option is used, the specified flavor or AUTH_NULL 791 * must be in the list returned by the server. 792 * 793 * AUTH_NULL has a special meaning when it's in the server list - it 794 * means that the server will ignore the rpc creds, so any flavor 795 * can be used but still use the sec= that was specified. 796 * 797 * Note also that the MNT procedure in MNTv1 does not return a list 798 * of supported security flavors. In this case, nfs_mount() fabricates 799 * a security flavor list containing just AUTH_NULL. 800 */ 801 for (i = 0; i < count; i++) { 802 flavor = server_authlist[i]; 803 804 if (nfs_auth_info_match(&ctx->auth_info, flavor)) 805 goto out; 806 807 if (flavor == RPC_AUTH_NULL) 808 found_auth_null = true; 809 } 810 811 if (found_auth_null) { 812 flavor = ctx->auth_info.flavors[0]; 813 goto out; 814 } 815 816 dfprintk(MOUNT, 817 "NFS: specified auth flavors not supported by server\n"); 818 return -EACCES; 819 820 out: 821 ctx->selected_flavor = flavor; 822 dfprintk(MOUNT, "NFS: using auth flavor %u\n", ctx->selected_flavor); 823 return 0; 824 } 825 826 /* 827 * Use the remote server's MOUNT service to request the NFS file handle 828 * corresponding to the provided path. 829 */ 830 static int nfs_request_mount(struct fs_context *fc, 831 struct nfs_fh *root_fh, 832 rpc_authflavor_t *server_authlist, 833 unsigned int *server_authlist_len) 834 { 835 struct nfs_fs_context *ctx = nfs_fc2context(fc); 836 struct nfs_mount_request request = { 837 .sap = &ctx->mount_server._address, 838 .dirpath = ctx->nfs_server.export_path, 839 .protocol = ctx->mount_server.protocol, 840 .fh = root_fh, 841 .noresvport = ctx->flags & NFS_MOUNT_NORESVPORT, 842 .auth_flav_len = server_authlist_len, 843 .auth_flavs = server_authlist, 844 .net = fc->net_ns, 845 }; 846 int status; 847 848 if (ctx->mount_server.version == 0) { 849 switch (ctx->version) { 850 default: 851 ctx->mount_server.version = NFS_MNT3_VERSION; 852 break; 853 case 2: 854 ctx->mount_server.version = NFS_MNT_VERSION; 855 } 856 } 857 request.version = ctx->mount_server.version; 858 859 if (ctx->mount_server.hostname) 860 request.hostname = ctx->mount_server.hostname; 861 else 862 request.hostname = ctx->nfs_server.hostname; 863 864 /* 865 * Construct the mount server's address. 866 */ 867 if (ctx->mount_server.address.sa_family == AF_UNSPEC) { 868 memcpy(request.sap, &ctx->nfs_server._address, 869 ctx->nfs_server.addrlen); 870 ctx->mount_server.addrlen = ctx->nfs_server.addrlen; 871 } 872 request.salen = ctx->mount_server.addrlen; 873 nfs_set_port(request.sap, &ctx->mount_server.port, 0); 874 875 /* 876 * Now ask the mount server to map our export path 877 * to a file handle. 878 */ 879 if ((request.protocol == XPRT_TRANSPORT_UDP) == 880 !(ctx->flags & NFS_MOUNT_TCP)) 881 /* 882 * NFS protocol and mount protocol are both UDP or neither UDP 883 * so timeouts are compatible. Use NFS timeouts for MOUNT 884 */ 885 status = nfs_mount(&request, ctx->timeo, ctx->retrans); 886 else 887 status = nfs_mount(&request, NFS_UNSPEC_TIMEO, NFS_UNSPEC_RETRANS); 888 if (status != 0) { 889 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n", 890 request.hostname, status); 891 return status; 892 } 893 894 return 0; 895 } 896 897 static struct nfs_server *nfs_try_mount_request(struct fs_context *fc) 898 { 899 struct nfs_fs_context *ctx = nfs_fc2context(fc); 900 int status; 901 unsigned int i; 902 bool tried_auth_unix = false; 903 bool auth_null_in_list = false; 904 struct nfs_server *server = ERR_PTR(-EACCES); 905 rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS]; 906 unsigned int authlist_len = ARRAY_SIZE(authlist); 907 908 /* make sure 'nolock'/'lock' override the 'local_lock' mount option */ 909 if (ctx->lock_status) { 910 if (ctx->lock_status == NFS_LOCK_NOLOCK) { 911 ctx->flags |= NFS_MOUNT_NONLM; 912 ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL); 913 } else { 914 ctx->flags &= ~NFS_MOUNT_NONLM; 915 ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL); 916 } 917 } 918 status = nfs_request_mount(fc, ctx->mntfh, authlist, &authlist_len); 919 if (status) 920 return ERR_PTR(status); 921 922 /* 923 * Was a sec= authflavor specified in the options? First, verify 924 * whether the server supports it, and then just try to use it if so. 925 */ 926 if (ctx->auth_info.flavor_len > 0) { 927 status = nfs_verify_authflavors(ctx, authlist, authlist_len); 928 dfprintk(MOUNT, "NFS: using auth flavor %u\n", 929 ctx->selected_flavor); 930 if (status) 931 return ERR_PTR(status); 932 return ctx->nfs_mod->rpc_ops->create_server(fc); 933 } 934 935 /* 936 * No sec= option was provided. RFC 2623, section 2.7 suggests we 937 * SHOULD prefer the flavor listed first. However, some servers list 938 * AUTH_NULL first. Avoid ever choosing AUTH_NULL. 939 */ 940 for (i = 0; i < authlist_len; ++i) { 941 rpc_authflavor_t flavor; 942 struct rpcsec_gss_info info; 943 944 flavor = authlist[i]; 945 switch (flavor) { 946 case RPC_AUTH_UNIX: 947 tried_auth_unix = true; 948 break; 949 case RPC_AUTH_NULL: 950 auth_null_in_list = true; 951 continue; 952 default: 953 if (rpcauth_get_gssinfo(flavor, &info) != 0) 954 continue; 955 break; 956 } 957 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor); 958 ctx->selected_flavor = flavor; 959 server = ctx->nfs_mod->rpc_ops->create_server(fc); 960 if (!IS_ERR(server)) 961 return server; 962 } 963 964 /* 965 * Nothing we tried so far worked. At this point, give up if we've 966 * already tried AUTH_UNIX or if the server's list doesn't contain 967 * AUTH_NULL 968 */ 969 if (tried_auth_unix || !auth_null_in_list) 970 return server; 971 972 /* Last chance! Try AUTH_UNIX */ 973 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX); 974 ctx->selected_flavor = RPC_AUTH_UNIX; 975 return ctx->nfs_mod->rpc_ops->create_server(fc); 976 } 977 978 int nfs_try_get_tree(struct fs_context *fc) 979 { 980 struct nfs_fs_context *ctx = nfs_fc2context(fc); 981 982 if (ctx->need_mount) 983 ctx->server = nfs_try_mount_request(fc); 984 else 985 ctx->server = ctx->nfs_mod->rpc_ops->create_server(fc); 986 987 return nfs_get_tree_common(fc); 988 } 989 EXPORT_SYMBOL_GPL(nfs_try_get_tree); 990 991 992 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \ 993 | NFS_MOUNT_SECURE \ 994 | NFS_MOUNT_TCP \ 995 | NFS_MOUNT_VER3 \ 996 | NFS_MOUNT_KERBEROS \ 997 | NFS_MOUNT_NONLM \ 998 | NFS_MOUNT_BROKEN_SUID \ 999 | NFS_MOUNT_STRICTLOCK \ 1000 | NFS_MOUNT_LEGACY_INTERFACE) 1001 1002 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \ 1003 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT)) 1004 1005 static int 1006 nfs_compare_remount_data(struct nfs_server *nfss, 1007 struct nfs_fs_context *ctx) 1008 { 1009 if ((ctx->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK || 1010 ctx->rsize != nfss->rsize || 1011 ctx->wsize != nfss->wsize || 1012 ctx->version != nfss->nfs_client->rpc_ops->version || 1013 ctx->minorversion != nfss->nfs_client->cl_minorversion || 1014 ctx->retrans != nfss->client->cl_timeout->to_retries || 1015 !nfs_auth_info_match(&ctx->auth_info, nfss->client->cl_auth->au_flavor) || 1016 ctx->acregmin != nfss->acregmin / HZ || 1017 ctx->acregmax != nfss->acregmax / HZ || 1018 ctx->acdirmin != nfss->acdirmin / HZ || 1019 ctx->acdirmax != nfss->acdirmax / HZ || 1020 ctx->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) || 1021 (ctx->options & NFS_OPTION_FSCACHE) != (nfss->options & NFS_OPTION_FSCACHE) || 1022 ctx->nfs_server.port != nfss->port || 1023 ctx->nfs_server.addrlen != nfss->nfs_client->cl_addrlen || 1024 !rpc_cmp_addr((struct sockaddr *)&ctx->nfs_server.address, 1025 (struct sockaddr *)&nfss->nfs_client->cl_addr)) 1026 return -EINVAL; 1027 1028 return 0; 1029 } 1030 1031 int nfs_reconfigure(struct fs_context *fc) 1032 { 1033 struct nfs_fs_context *ctx = nfs_fc2context(fc); 1034 struct super_block *sb = fc->root->d_sb; 1035 struct nfs_server *nfss = sb->s_fs_info; 1036 int ret; 1037 1038 sync_filesystem(sb); 1039 1040 /* 1041 * Userspace mount programs that send binary options generally send 1042 * them populated with default values. We have no way to know which 1043 * ones were explicitly specified. Fall back to legacy behavior and 1044 * just return success. 1045 */ 1046 if (ctx->skip_reconfig_option_check) 1047 return 0; 1048 1049 /* 1050 * noac is a special case. It implies -o sync, but that's not 1051 * necessarily reflected in the mtab options. reconfigure_super 1052 * will clear SB_SYNCHRONOUS if -o sync wasn't specified in the 1053 * remount options, so we have to explicitly reset it. 1054 */ 1055 if (ctx->flags & NFS_MOUNT_NOAC) { 1056 fc->sb_flags |= SB_SYNCHRONOUS; 1057 fc->sb_flags_mask |= SB_SYNCHRONOUS; 1058 } 1059 1060 /* compare new mount options with old ones */ 1061 ret = nfs_compare_remount_data(nfss, ctx); 1062 if (ret) 1063 return ret; 1064 1065 return nfs_probe_server(nfss, NFS_FH(d_inode(fc->root))); 1066 } 1067 EXPORT_SYMBOL_GPL(nfs_reconfigure); 1068 1069 /* 1070 * Finish setting up an NFS superblock 1071 */ 1072 static void nfs_fill_super(struct super_block *sb, struct nfs_fs_context *ctx) 1073 { 1074 struct nfs_server *server = NFS_SB(sb); 1075 1076 sb->s_blocksize_bits = 0; 1077 sb->s_blocksize = 0; 1078 sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr; 1079 sb->s_op = server->nfs_client->cl_nfs_mod->sops; 1080 if (server->bsize) 1081 sb->s_blocksize = 1082 nfs_block_size(server->bsize, &sb->s_blocksize_bits); 1083 1084 switch (server->nfs_client->rpc_ops->version) { 1085 case 2: 1086 sb->s_time_gran = 1000; 1087 sb->s_time_min = 0; 1088 sb->s_time_max = U32_MAX; 1089 break; 1090 case 3: 1091 /* 1092 * The VFS shouldn't apply the umask to mode bits. 1093 * We will do so ourselves when necessary. 1094 */ 1095 sb->s_flags |= SB_POSIXACL; 1096 sb->s_time_gran = 1; 1097 sb->s_time_min = 0; 1098 sb->s_time_max = U32_MAX; 1099 sb->s_export_op = &nfs_export_ops; 1100 break; 1101 case 4: 1102 sb->s_iflags |= SB_I_NOUMASK; 1103 sb->s_time_gran = 1; 1104 sb->s_time_min = S64_MIN; 1105 sb->s_time_max = S64_MAX; 1106 if (server->caps & NFS_CAP_ATOMIC_OPEN_V1) 1107 sb->s_export_op = &nfs_export_ops; 1108 break; 1109 } 1110 1111 sb->s_magic = NFS_SUPER_MAGIC; 1112 1113 /* We probably want something more informative here */ 1114 snprintf(sb->s_id, sizeof(sb->s_id), 1115 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev)); 1116 1117 if (sb->s_blocksize == 0) 1118 sb->s_blocksize = nfs_block_bits(server->wsize, 1119 &sb->s_blocksize_bits); 1120 1121 nfs_super_set_maxbytes(sb, server->maxfilesize); 1122 nfs_sysfs_move_server_to_sb(sb); 1123 server->has_sec_mnt_opts = ctx->has_sec_mnt_opts; 1124 } 1125 1126 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, 1127 const struct fs_context *fc) 1128 { 1129 const struct nfs_server *a = s->s_fs_info; 1130 const struct rpc_clnt *clnt_a = a->client; 1131 const struct rpc_clnt *clnt_b = b->client; 1132 1133 if ((s->s_flags & NFS_SB_MASK) != (fc->sb_flags & NFS_SB_MASK)) 1134 goto Ebusy; 1135 if (a->nfs_client != b->nfs_client) 1136 goto Ebusy; 1137 if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK) 1138 goto Ebusy; 1139 if (a->wsize != b->wsize) 1140 goto Ebusy; 1141 if (a->rsize != b->rsize) 1142 goto Ebusy; 1143 if (a->acregmin != b->acregmin) 1144 goto Ebusy; 1145 if (a->acregmax != b->acregmax) 1146 goto Ebusy; 1147 if (a->acdirmin != b->acdirmin) 1148 goto Ebusy; 1149 if (a->acdirmax != b->acdirmax) 1150 goto Ebusy; 1151 if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor) 1152 goto Ebusy; 1153 return 1; 1154 Ebusy: 1155 return 0; 1156 } 1157 1158 static int nfs_set_super(struct super_block *s, struct fs_context *fc) 1159 { 1160 struct nfs_server *server = fc->s_fs_info; 1161 int ret; 1162 1163 set_default_d_op(s, server->nfs_client->rpc_ops->dentry_ops); 1164 ret = set_anon_super(s, server); 1165 if (ret == 0) 1166 server->s_dev = s->s_dev; 1167 return ret; 1168 } 1169 1170 static int nfs_compare_super_address(struct nfs_server *server1, 1171 struct nfs_server *server2) 1172 { 1173 struct rpc_xprt *xprt1, *xprt2; 1174 struct sockaddr *sap1, *sap2; 1175 1176 rcu_read_lock(); 1177 1178 xprt1 = rcu_dereference(server1->client->cl_xprt); 1179 xprt2 = rcu_dereference(server2->client->cl_xprt); 1180 1181 if (!net_eq(xprt1->xprt_net, xprt2->xprt_net)) 1182 goto out_unlock; 1183 1184 rcu_read_unlock(); 1185 1186 sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr; 1187 sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr; 1188 1189 if (sap1->sa_family != sap2->sa_family) 1190 return 0; 1191 1192 switch (sap1->sa_family) { 1193 case AF_INET: { 1194 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1; 1195 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2; 1196 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr) 1197 return 0; 1198 if (sin1->sin_port != sin2->sin_port) 1199 return 0; 1200 break; 1201 } 1202 case AF_INET6: { 1203 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1; 1204 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2; 1205 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr)) 1206 return 0; 1207 if (sin1->sin6_port != sin2->sin6_port) 1208 return 0; 1209 break; 1210 } 1211 default: 1212 return 0; 1213 } 1214 1215 return 1; 1216 1217 out_unlock: 1218 rcu_read_unlock(); 1219 return 0; 1220 } 1221 1222 static int nfs_compare_userns(const struct nfs_server *old, 1223 const struct nfs_server *new) 1224 { 1225 const struct user_namespace *oldns = &init_user_ns; 1226 const struct user_namespace *newns = &init_user_ns; 1227 1228 if (old->client && old->client->cl_cred) 1229 oldns = old->client->cl_cred->user_ns; 1230 if (new->client && new->client->cl_cred) 1231 newns = new->client->cl_cred->user_ns; 1232 if (oldns != newns) 1233 return 0; 1234 return 1; 1235 } 1236 1237 static int nfs_compare_super(struct super_block *sb, struct fs_context *fc) 1238 { 1239 struct nfs_server *server = fc->s_fs_info, *old = NFS_SB(sb); 1240 1241 if (!nfs_compare_super_address(old, server)) 1242 return 0; 1243 /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */ 1244 if (old->flags & NFS_MOUNT_UNSHARED) 1245 return 0; 1246 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0) 1247 return 0; 1248 if (!nfs_compare_userns(old, server)) 1249 return 0; 1250 if ((old->has_sec_mnt_opts || fc->security) && 1251 security_sb_mnt_opts_compat(sb, fc->security)) 1252 return 0; 1253 return nfs_compare_mount_options(sb, server, fc); 1254 } 1255 1256 #ifdef CONFIG_NFS_FSCACHE 1257 static int nfs_get_cache_cookie(struct super_block *sb, 1258 struct nfs_fs_context *ctx) 1259 { 1260 struct nfs_server *nfss = NFS_SB(sb); 1261 char *uniq = NULL; 1262 int ulen = 0; 1263 1264 nfss->fscache = NULL; 1265 1266 if (!ctx) 1267 return 0; 1268 1269 if (ctx->clone_data.sb) { 1270 struct nfs_server *mnt_s = NFS_SB(ctx->clone_data.sb); 1271 if (!(mnt_s->options & NFS_OPTION_FSCACHE)) 1272 return 0; 1273 if (mnt_s->fscache_uniq) { 1274 uniq = mnt_s->fscache_uniq; 1275 ulen = strlen(uniq); 1276 } 1277 } else { 1278 if (!(ctx->options & NFS_OPTION_FSCACHE)) 1279 return 0; 1280 if (ctx->fscache_uniq) { 1281 uniq = ctx->fscache_uniq; 1282 ulen = strlen(ctx->fscache_uniq); 1283 } 1284 } 1285 1286 return nfs_fscache_get_super_cookie(sb, uniq, ulen); 1287 } 1288 #else 1289 static int nfs_get_cache_cookie(struct super_block *sb, 1290 struct nfs_fs_context *ctx) 1291 { 1292 return 0; 1293 } 1294 #endif 1295 1296 int nfs_get_tree_common(struct fs_context *fc) 1297 { 1298 struct nfs_fs_context *ctx = nfs_fc2context(fc); 1299 struct super_block *s; 1300 int (*compare_super)(struct super_block *, struct fs_context *) = nfs_compare_super; 1301 struct nfs_server *server = ctx->server; 1302 int error; 1303 1304 ctx->server = NULL; 1305 if (IS_ERR(server)) 1306 return PTR_ERR(server); 1307 1308 if (server->flags & NFS_MOUNT_UNSHARED) 1309 compare_super = NULL; 1310 1311 /* -o noac implies -o sync */ 1312 if (server->flags & NFS_MOUNT_NOAC) 1313 fc->sb_flags |= SB_SYNCHRONOUS; 1314 1315 /* Get a superblock - note that we may end up sharing one that already exists */ 1316 fc->s_fs_info = server; 1317 s = sget_fc(fc, compare_super, nfs_set_super); 1318 fc->s_fs_info = NULL; 1319 if (IS_ERR(s)) { 1320 error = PTR_ERR(s); 1321 nfs_errorf(fc, "NFS: Couldn't get superblock"); 1322 goto out_err_nosb; 1323 } 1324 1325 if (s->s_fs_info != server) { 1326 nfs_free_server(server); 1327 server = NULL; 1328 } else { 1329 error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev), 1330 MINOR(server->s_dev)); 1331 if (error) 1332 goto error_splat_super; 1333 s->s_bdi->io_pages = server->rpages; 1334 server->super = s; 1335 } 1336 1337 if (!s->s_root) { 1338 /* initial superblock/root creation */ 1339 nfs_fill_super(s, ctx); 1340 error = nfs_get_cache_cookie(s, ctx); 1341 if (error < 0) 1342 goto error_splat_super; 1343 } 1344 1345 error = nfs_get_root(s, fc); 1346 if (error < 0) { 1347 nfs_errorf(fc, "NFS: Couldn't get root dentry"); 1348 goto error_splat_super; 1349 } 1350 1351 s->s_flags |= SB_ACTIVE; 1352 error = 0; 1353 1354 out: 1355 return error; 1356 1357 out_err_nosb: 1358 nfs_free_server(server); 1359 goto out; 1360 error_splat_super: 1361 deactivate_locked_super(s); 1362 goto out; 1363 } 1364 1365 /* 1366 * Destroy an NFS superblock 1367 */ 1368 void nfs_kill_super(struct super_block *s) 1369 { 1370 struct nfs_server *server = NFS_SB(s); 1371 1372 nfs_sysfs_move_sb_to_server(server); 1373 kill_anon_super(s); 1374 1375 nfs_fscache_release_super_cookie(s); 1376 1377 nfs_free_server(server); 1378 } 1379 EXPORT_SYMBOL_GPL(nfs_kill_super); 1380 1381 #if IS_ENABLED(CONFIG_NFS_V4) 1382 1383 /* 1384 * NFS v4 module parameters need to stay in the 1385 * NFS client for backwards compatibility 1386 */ 1387 unsigned int nfs_callback_set_tcpport; 1388 unsigned short nfs_callback_nr_threads; 1389 /* Default cache timeout is 10 minutes */ 1390 unsigned int nfs_idmap_cache_timeout = 600; 1391 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */ 1392 bool nfs4_disable_idmapping = true; 1393 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE; 1394 unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE; 1395 unsigned short send_implementation_id = 1; 1396 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = ""; 1397 bool recover_lost_locks = false; 1398 short nfs_delay_retrans = -1; 1399 1400 EXPORT_SYMBOL_GPL(nfs_callback_nr_threads); 1401 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport); 1402 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout); 1403 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping); 1404 EXPORT_SYMBOL_GPL(max_session_slots); 1405 EXPORT_SYMBOL_GPL(max_session_cb_slots); 1406 EXPORT_SYMBOL_GPL(send_implementation_id); 1407 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier); 1408 EXPORT_SYMBOL_GPL(recover_lost_locks); 1409 EXPORT_SYMBOL_GPL(nfs_delay_retrans); 1410 1411 #define NFS_CALLBACK_MAXPORTNR (65535U) 1412 1413 static int param_set_portnr(const char *val, const struct kernel_param *kp) 1414 { 1415 unsigned long num; 1416 int ret; 1417 1418 if (!val) 1419 return -EINVAL; 1420 ret = kstrtoul(val, 0, &num); 1421 if (ret || num > NFS_CALLBACK_MAXPORTNR) 1422 return -EINVAL; 1423 *((unsigned int *)kp->arg) = num; 1424 return 0; 1425 } 1426 static const struct kernel_param_ops param_ops_portnr = { 1427 .set = param_set_portnr, 1428 .get = param_get_uint, 1429 }; 1430 #define param_check_portnr(name, p) __param_check(name, p, unsigned int) 1431 1432 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644); 1433 module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644); 1434 MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be " 1435 "assigned to the NFSv4 callback channels."); 1436 module_param(nfs_idmap_cache_timeout, int, 0644); 1437 module_param(nfs4_disable_idmapping, bool, 0644); 1438 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier, 1439 NFS4_CLIENT_ID_UNIQ_LEN, 0600); 1440 MODULE_PARM_DESC(nfs4_disable_idmapping, 1441 "Turn off NFSv4 idmapping when using 'sec=sys'"); 1442 module_param(max_session_slots, ushort, 0644); 1443 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 " 1444 "requests the client will negotiate"); 1445 module_param(max_session_cb_slots, ushort, 0644); 1446 MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 " 1447 "callbacks the client will process for a given server"); 1448 module_param(send_implementation_id, ushort, 0644); 1449 MODULE_PARM_DESC(send_implementation_id, 1450 "Send implementation ID with NFSv4.1 exchange_id"); 1451 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string"); 1452 1453 module_param(recover_lost_locks, bool, 0644); 1454 MODULE_PARM_DESC(recover_lost_locks, 1455 "If the server reports that a lock might be lost, " 1456 "try to recover it risking data corruption."); 1457 1458 module_param_named(delay_retrans, nfs_delay_retrans, short, 0644); 1459 MODULE_PARM_DESC(delay_retrans, 1460 "Unless negative, specifies the number of times the NFSv4 " 1461 "client retries a request before returning an EAGAIN error, " 1462 "after a reply of NFS4ERR_DELAY from the server."); 1463 #endif /* CONFIG_NFS_V4 */ 1464