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 static int __nfs_list_for_each_server(struct list_head *head, 216 int (*fn)(struct nfs_server *, void *), 217 void *data) 218 { 219 struct nfs_server *server, *last = NULL; 220 int ret = 0; 221 222 rcu_read_lock(); 223 list_for_each_entry_rcu(server, head, client_link) { 224 if (!(server->super && nfs_sb_active(server->super))) 225 continue; 226 rcu_read_unlock(); 227 if (last) 228 nfs_sb_deactive(last->super); 229 last = server; 230 ret = fn(server, data); 231 if (ret) 232 goto out; 233 cond_resched(); 234 rcu_read_lock(); 235 } 236 rcu_read_unlock(); 237 out: 238 if (last) 239 nfs_sb_deactive(last->super); 240 return ret; 241 } 242 243 int nfs_client_for_each_server(struct nfs_client *clp, 244 int (*fn)(struct nfs_server *, void *), 245 void *data) 246 { 247 return __nfs_list_for_each_server(&clp->cl_superblocks, fn, data); 248 } 249 EXPORT_SYMBOL_GPL(nfs_client_for_each_server); 250 251 /* 252 * Deliver file system statistics to userspace 253 */ 254 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf) 255 { 256 struct nfs_server *server = NFS_SB(dentry->d_sb); 257 unsigned char blockbits; 258 unsigned long blockres; 259 struct nfs_fh *fh = NFS_FH(d_inode(dentry)); 260 struct nfs_fsstat res; 261 int error = -ENOMEM; 262 263 res.fattr = nfs_alloc_fattr(); 264 if (res.fattr == NULL) 265 goto out_err; 266 267 error = server->nfs_client->rpc_ops->statfs(server, fh, &res); 268 if (unlikely(error == -ESTALE)) { 269 struct dentry *pd_dentry; 270 271 pd_dentry = dget_parent(dentry); 272 nfs_zap_caches(d_inode(pd_dentry)); 273 dput(pd_dentry); 274 } 275 nfs_free_fattr(res.fattr); 276 if (error < 0) 277 goto out_err; 278 279 buf->f_type = NFS_SUPER_MAGIC; 280 281 /* 282 * Current versions of glibc do not correctly handle the 283 * case where f_frsize != f_bsize. Eventually we want to 284 * report the value of wtmult in this field. 285 */ 286 buf->f_frsize = dentry->d_sb->s_blocksize; 287 288 /* 289 * On most *nix systems, f_blocks, f_bfree, and f_bavail 290 * are reported in units of f_frsize. Linux hasn't had 291 * an f_frsize field in its statfs struct until recently, 292 * thus historically Linux's sys_statfs reports these 293 * fields in units of f_bsize. 294 */ 295 buf->f_bsize = dentry->d_sb->s_blocksize; 296 blockbits = dentry->d_sb->s_blocksize_bits; 297 blockres = (1 << blockbits) - 1; 298 buf->f_blocks = (res.tbytes + blockres) >> blockbits; 299 buf->f_bfree = (res.fbytes + blockres) >> blockbits; 300 buf->f_bavail = (res.abytes + blockres) >> blockbits; 301 302 buf->f_files = res.tfiles; 303 buf->f_ffree = res.afiles; 304 305 buf->f_namelen = server->namelen; 306 307 return 0; 308 309 out_err: 310 dprintk("%s: statfs error = %d\n", __func__, -error); 311 return error; 312 } 313 EXPORT_SYMBOL_GPL(nfs_statfs); 314 315 /* 316 * Map the security flavour number to a name 317 */ 318 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour) 319 { 320 static const struct { 321 rpc_authflavor_t flavour; 322 const char *str; 323 } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = { 324 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */ 325 { RPC_AUTH_NULL, "null" }, 326 { RPC_AUTH_UNIX, "sys" }, 327 { RPC_AUTH_GSS_KRB5, "krb5" }, 328 { RPC_AUTH_GSS_KRB5I, "krb5i" }, 329 { RPC_AUTH_GSS_KRB5P, "krb5p" }, 330 { RPC_AUTH_GSS_LKEY, "lkey" }, 331 { RPC_AUTH_GSS_LKEYI, "lkeyi" }, 332 { RPC_AUTH_GSS_LKEYP, "lkeyp" }, 333 { RPC_AUTH_GSS_SPKM, "spkm" }, 334 { RPC_AUTH_GSS_SPKMI, "spkmi" }, 335 { RPC_AUTH_GSS_SPKMP, "spkmp" }, 336 { UINT_MAX, "unknown" } 337 }; 338 int i; 339 340 for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) { 341 if (sec_flavours[i].flavour == flavour) 342 break; 343 } 344 return sec_flavours[i].str; 345 } 346 347 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss, 348 int showdefaults) 349 { 350 struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address; 351 char *proto = NULL; 352 353 switch (sap->sa_family) { 354 case AF_INET: 355 switch (nfss->mountd_protocol) { 356 case IPPROTO_UDP: 357 proto = RPCBIND_NETID_UDP; 358 break; 359 case IPPROTO_TCP: 360 proto = RPCBIND_NETID_TCP; 361 break; 362 } 363 break; 364 case AF_INET6: 365 switch (nfss->mountd_protocol) { 366 case IPPROTO_UDP: 367 proto = RPCBIND_NETID_UDP6; 368 break; 369 case IPPROTO_TCP: 370 proto = RPCBIND_NETID_TCP6; 371 break; 372 } 373 break; 374 } 375 if (proto || showdefaults) 376 seq_printf(m, ",mountproto=%s", proto ?: "auto"); 377 } 378 379 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss, 380 int showdefaults) 381 { 382 struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address; 383 384 if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE) 385 return; 386 387 switch (sap->sa_family) { 388 case AF_INET: { 389 struct sockaddr_in *sin = (struct sockaddr_in *)sap; 390 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr); 391 break; 392 } 393 case AF_INET6: { 394 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap; 395 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr); 396 break; 397 } 398 default: 399 if (showdefaults) 400 seq_puts(m, ",mountaddr=unspecified"); 401 } 402 403 if (nfss->mountd_version || showdefaults) 404 seq_printf(m, ",mountvers=%u", nfss->mountd_version); 405 if ((nfss->mountd_port && 406 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) || 407 showdefaults) 408 seq_printf(m, ",mountport=%u", nfss->mountd_port); 409 410 nfs_show_mountd_netid(m, nfss, showdefaults); 411 } 412 413 #if IS_ENABLED(CONFIG_NFS_V4) 414 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss, 415 int showdefaults) 416 { 417 struct nfs_client *clp = nfss->nfs_client; 418 419 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr); 420 } 421 #else 422 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss, 423 int showdefaults) 424 { 425 } 426 #endif 427 428 static void nfs_show_nfs_version(struct seq_file *m, 429 unsigned int version, 430 unsigned int minorversion) 431 { 432 seq_printf(m, ",vers=%u", version); 433 if (version == 4) 434 seq_printf(m, ".%u", minorversion); 435 } 436 437 /* 438 * Describe the mount options in force on this server representation 439 */ 440 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, 441 int showdefaults) 442 { 443 static const struct proc_nfs_info { 444 int flag; 445 const char *str; 446 const char *nostr; 447 } nfs_info[] = { 448 { NFS_MOUNT_SOFT, ",soft", "" }, 449 { NFS_MOUNT_SOFTERR, ",softerr", "" }, 450 { NFS_MOUNT_SOFTREVAL, ",softreval", "" }, 451 { NFS_MOUNT_POSIX, ",posix", "" }, 452 { NFS_MOUNT_NOCTO, ",nocto", "" }, 453 { NFS_MOUNT_NOAC, ",noac", "" }, 454 { NFS_MOUNT_NONLM, ",nolock", "" }, 455 { NFS_MOUNT_NOACL, ",noacl", "" }, 456 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" }, 457 { NFS_MOUNT_UNSHARED, ",nosharecache", "" }, 458 { NFS_MOUNT_NORESVPORT, ",noresvport", "" }, 459 { 0, NULL, NULL } 460 }; 461 const struct proc_nfs_info *nfs_infop; 462 struct nfs_client *clp = nfss->nfs_client; 463 u32 version = clp->rpc_ops->version; 464 int local_flock, local_fcntl; 465 466 nfs_show_nfs_version(m, version, clp->cl_minorversion); 467 seq_printf(m, ",rsize=%u", nfss->rsize); 468 seq_printf(m, ",wsize=%u", nfss->wsize); 469 if (nfss->bsize != 0) 470 seq_printf(m, ",bsize=%u", nfss->bsize); 471 seq_printf(m, ",namlen=%u", nfss->namelen); 472 if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults) 473 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ); 474 if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults) 475 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ); 476 if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults) 477 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ); 478 if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults) 479 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ); 480 if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))) 481 seq_puts(m, ",hard"); 482 for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) { 483 if (nfss->flags & nfs_infop->flag) 484 seq_puts(m, nfs_infop->str); 485 else 486 seq_puts(m, nfs_infop->nostr); 487 } 488 rcu_read_lock(); 489 seq_printf(m, ",proto=%s", 490 rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID)); 491 rcu_read_unlock(); 492 if (clp->cl_nconnect > 0) 493 seq_printf(m, ",nconnect=%u", clp->cl_nconnect); 494 if (version == 4) { 495 if (clp->cl_max_connect > 1) 496 seq_printf(m, ",max_connect=%u", clp->cl_max_connect); 497 if (nfss->port != NFS_PORT) 498 seq_printf(m, ",port=%u", nfss->port); 499 } else 500 if (nfss->port) 501 seq_printf(m, ",port=%u", nfss->port); 502 503 seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ); 504 seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries); 505 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor)); 506 switch (clp->cl_xprtsec.policy) { 507 case RPC_XPRTSEC_TLS_ANON: 508 seq_puts(m, ",xprtsec=tls"); 509 break; 510 case RPC_XPRTSEC_TLS_X509: 511 seq_puts(m, ",xprtsec=mtls"); 512 break; 513 default: 514 break; 515 } 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 #ifdef CONFIG_NFS_V4_1 597 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 #else 603 static void show_sessions(struct seq_file *m, struct nfs_server *server) {} 604 #endif 605 #endif 606 607 #ifdef CONFIG_NFS_V4_1 608 static void show_pnfs(struct seq_file *m, struct nfs_server *server) 609 { 610 seq_printf(m, ",pnfs="); 611 if (server->pnfs_curr_ld) 612 seq_printf(m, "%s", server->pnfs_curr_ld->name); 613 else 614 seq_printf(m, "not configured"); 615 } 616 617 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss) 618 { 619 if (nfss->nfs_client && nfss->nfs_client->cl_implid) { 620 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid; 621 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s'," 622 "date='%llu,%u'", 623 impl_id->name, impl_id->domain, 624 impl_id->date.seconds, impl_id->date.nseconds); 625 } 626 } 627 #else 628 #if IS_ENABLED(CONFIG_NFS_V4) 629 static void show_pnfs(struct seq_file *m, struct nfs_server *server) 630 { 631 } 632 #endif 633 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss) 634 { 635 } 636 #endif 637 638 int nfs_show_devname(struct seq_file *m, struct dentry *root) 639 { 640 char *page = (char *) __get_free_page(GFP_KERNEL); 641 char *devname, *dummy; 642 int err = 0; 643 if (!page) 644 return -ENOMEM; 645 devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0); 646 if (IS_ERR(devname)) 647 err = PTR_ERR(devname); 648 else 649 seq_escape(m, devname, " \t\n\\"); 650 free_page((unsigned long)page); 651 return err; 652 } 653 EXPORT_SYMBOL_GPL(nfs_show_devname); 654 655 int nfs_show_path(struct seq_file *m, struct dentry *dentry) 656 { 657 seq_puts(m, "/"); 658 return 0; 659 } 660 EXPORT_SYMBOL_GPL(nfs_show_path); 661 662 /* 663 * Present statistical information for this VFS mountpoint 664 */ 665 int nfs_show_stats(struct seq_file *m, struct dentry *root) 666 { 667 int i, cpu; 668 struct nfs_server *nfss = NFS_SB(root->d_sb); 669 struct rpc_auth *auth = nfss->client->cl_auth; 670 struct nfs_iostats totals = { }; 671 672 seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS); 673 674 /* 675 * Display all mount option settings 676 */ 677 seq_puts(m, "\n\topts:\t"); 678 seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw"); 679 seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : ""); 680 seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : ""); 681 seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : ""); 682 nfs_show_mount_options(m, nfss, 1); 683 684 seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ); 685 686 show_implementation_id(m, nfss); 687 688 seq_puts(m, "\n\tcaps:\t"); 689 seq_printf(m, "caps=0x%x", nfss->caps); 690 seq_printf(m, ",wtmult=%u", nfss->wtmult); 691 seq_printf(m, ",dtsize=%u", nfss->dtsize); 692 seq_printf(m, ",bsize=%u", nfss->bsize); 693 seq_printf(m, ",namlen=%u", nfss->namelen); 694 695 #if IS_ENABLED(CONFIG_NFS_V4) 696 if (nfss->nfs_client->rpc_ops->version == 4) { 697 seq_puts(m, "\n\tnfsv4:\t"); 698 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]); 699 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]); 700 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]); 701 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask); 702 show_sessions(m, nfss); 703 show_pnfs(m, nfss); 704 show_lease(m, nfss); 705 } 706 #endif 707 708 /* 709 * Display security flavor in effect for this mount 710 */ 711 seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor); 712 if (auth->au_flavor) 713 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor); 714 715 /* 716 * Display superblock I/O counters 717 */ 718 for_each_possible_cpu(cpu) { 719 struct nfs_iostats *stats; 720 721 preempt_disable(); 722 stats = per_cpu_ptr(nfss->io_stats, cpu); 723 724 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 725 totals.events[i] += stats->events[i]; 726 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 727 totals.bytes[i] += stats->bytes[i]; 728 729 preempt_enable(); 730 } 731 732 seq_puts(m, "\n\tevents:\t"); 733 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 734 seq_printf(m, "%lu ", totals.events[i]); 735 seq_puts(m, "\n\tbytes:\t"); 736 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 737 seq_printf(m, "%Lu ", totals.bytes[i]); 738 seq_putc(m, '\n'); 739 740 rpc_clnt_show_stats(m, nfss->client); 741 742 return 0; 743 } 744 EXPORT_SYMBOL_GPL(nfs_show_stats); 745 746 /* 747 * Begin unmount by attempting to remove all automounted mountpoints we added 748 * in response to xdev traversals and referrals 749 */ 750 void nfs_umount_begin(struct super_block *sb) 751 { 752 struct nfs_server *server; 753 struct rpc_clnt *rpc; 754 755 server = NFS_SB(sb); 756 /* -EIO all pending I/O */ 757 rpc = server->client_acl; 758 if (!IS_ERR(rpc)) 759 rpc_killall_tasks(rpc); 760 rpc = server->client; 761 if (!IS_ERR(rpc)) 762 rpc_killall_tasks(rpc); 763 } 764 EXPORT_SYMBOL_GPL(nfs_umount_begin); 765 766 /* 767 * Return true if 'match' is in auth_info or auth_info is empty. 768 * Return false otherwise. 769 */ 770 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info, 771 rpc_authflavor_t match) 772 { 773 int i; 774 775 if (!auth_info->flavor_len) 776 return true; 777 778 for (i = 0; i < auth_info->flavor_len; i++) { 779 if (auth_info->flavors[i] == match) 780 return true; 781 } 782 return false; 783 } 784 EXPORT_SYMBOL_GPL(nfs_auth_info_match); 785 786 /* 787 * Ensure that a specified authtype in ctx->auth_info is supported by 788 * the server. Returns 0 and sets ctx->selected_flavor if it's ok, and 789 * -EACCES if not. 790 */ 791 static int nfs_verify_authflavors(struct nfs_fs_context *ctx, 792 rpc_authflavor_t *server_authlist, 793 unsigned int count) 794 { 795 rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR; 796 bool found_auth_null = false; 797 unsigned int i; 798 799 /* 800 * If the sec= mount option is used, the specified flavor or AUTH_NULL 801 * must be in the list returned by the server. 802 * 803 * AUTH_NULL has a special meaning when it's in the server list - it 804 * means that the server will ignore the rpc creds, so any flavor 805 * can be used but still use the sec= that was specified. 806 * 807 * Note also that the MNT procedure in MNTv1 does not return a list 808 * of supported security flavors. In this case, nfs_mount() fabricates 809 * a security flavor list containing just AUTH_NULL. 810 */ 811 for (i = 0; i < count; i++) { 812 flavor = server_authlist[i]; 813 814 if (nfs_auth_info_match(&ctx->auth_info, flavor)) 815 goto out; 816 817 if (flavor == RPC_AUTH_NULL) 818 found_auth_null = true; 819 } 820 821 if (found_auth_null) { 822 flavor = ctx->auth_info.flavors[0]; 823 goto out; 824 } 825 826 dfprintk(MOUNT, 827 "NFS: specified auth flavors not supported by server\n"); 828 return -EACCES; 829 830 out: 831 ctx->selected_flavor = flavor; 832 dfprintk(MOUNT, "NFS: using auth flavor %u\n", ctx->selected_flavor); 833 return 0; 834 } 835 836 /* 837 * Use the remote server's MOUNT service to request the NFS file handle 838 * corresponding to the provided path. 839 */ 840 static int nfs_request_mount(struct fs_context *fc, 841 struct nfs_fh *root_fh, 842 rpc_authflavor_t *server_authlist, 843 unsigned int *server_authlist_len) 844 { 845 struct nfs_fs_context *ctx = nfs_fc2context(fc); 846 struct nfs_mount_request request = { 847 .sap = &ctx->mount_server._address, 848 .dirpath = ctx->nfs_server.export_path, 849 .protocol = ctx->mount_server.protocol, 850 .fh = root_fh, 851 .noresvport = ctx->flags & NFS_MOUNT_NORESVPORT, 852 .auth_flav_len = server_authlist_len, 853 .auth_flavs = server_authlist, 854 .net = fc->net_ns, 855 }; 856 int status; 857 858 if (ctx->mount_server.version == 0) { 859 switch (ctx->version) { 860 default: 861 ctx->mount_server.version = NFS_MNT3_VERSION; 862 break; 863 case 2: 864 ctx->mount_server.version = NFS_MNT_VERSION; 865 } 866 } 867 request.version = ctx->mount_server.version; 868 869 if (ctx->mount_server.hostname) 870 request.hostname = ctx->mount_server.hostname; 871 else 872 request.hostname = ctx->nfs_server.hostname; 873 874 /* 875 * Construct the mount server's address. 876 */ 877 if (ctx->mount_server.address.sa_family == AF_UNSPEC) { 878 memcpy(request.sap, &ctx->nfs_server._address, 879 ctx->nfs_server.addrlen); 880 ctx->mount_server.addrlen = ctx->nfs_server.addrlen; 881 } 882 request.salen = ctx->mount_server.addrlen; 883 nfs_set_port(request.sap, &ctx->mount_server.port, 0); 884 885 /* 886 * Now ask the mount server to map our export path 887 * to a file handle. 888 */ 889 if ((request.protocol == XPRT_TRANSPORT_UDP) == 890 !(ctx->flags & NFS_MOUNT_TCP)) 891 /* 892 * NFS protocol and mount protocol are both UDP or neither UDP 893 * so timeouts are compatible. Use NFS timeouts for MOUNT 894 */ 895 status = nfs_mount(&request, ctx->timeo, ctx->retrans); 896 else 897 status = nfs_mount(&request, NFS_UNSPEC_TIMEO, NFS_UNSPEC_RETRANS); 898 if (status != 0) { 899 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n", 900 request.hostname, status); 901 return status; 902 } 903 904 return 0; 905 } 906 907 static struct nfs_server *nfs_try_mount_request(struct fs_context *fc) 908 { 909 struct nfs_fs_context *ctx = nfs_fc2context(fc); 910 int status; 911 unsigned int i; 912 bool tried_auth_unix = false; 913 bool auth_null_in_list = false; 914 struct nfs_server *server = ERR_PTR(-EACCES); 915 rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS]; 916 unsigned int authlist_len = ARRAY_SIZE(authlist); 917 918 /* make sure 'nolock'/'lock' override the 'local_lock' mount option */ 919 if (ctx->lock_status) { 920 if (ctx->lock_status == NFS_LOCK_NOLOCK) { 921 ctx->flags |= NFS_MOUNT_NONLM; 922 ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL); 923 } else { 924 ctx->flags &= ~NFS_MOUNT_NONLM; 925 ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL); 926 } 927 } 928 status = nfs_request_mount(fc, ctx->mntfh, authlist, &authlist_len); 929 if (status) 930 return ERR_PTR(status); 931 932 /* 933 * Was a sec= authflavor specified in the options? First, verify 934 * whether the server supports it, and then just try to use it if so. 935 */ 936 if (ctx->auth_info.flavor_len > 0) { 937 status = nfs_verify_authflavors(ctx, authlist, authlist_len); 938 dfprintk(MOUNT, "NFS: using auth flavor %u\n", 939 ctx->selected_flavor); 940 if (status) 941 return ERR_PTR(status); 942 return ctx->nfs_mod->rpc_ops->create_server(fc); 943 } 944 945 /* 946 * No sec= option was provided. RFC 2623, section 2.7 suggests we 947 * SHOULD prefer the flavor listed first. However, some servers list 948 * AUTH_NULL first. Avoid ever choosing AUTH_NULL. 949 */ 950 for (i = 0; i < authlist_len; ++i) { 951 rpc_authflavor_t flavor; 952 struct rpcsec_gss_info info; 953 954 flavor = authlist[i]; 955 switch (flavor) { 956 case RPC_AUTH_UNIX: 957 tried_auth_unix = true; 958 break; 959 case RPC_AUTH_NULL: 960 auth_null_in_list = true; 961 continue; 962 default: 963 if (rpcauth_get_gssinfo(flavor, &info) != 0) 964 continue; 965 break; 966 } 967 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor); 968 ctx->selected_flavor = flavor; 969 server = ctx->nfs_mod->rpc_ops->create_server(fc); 970 if (!IS_ERR(server)) 971 return server; 972 } 973 974 /* 975 * Nothing we tried so far worked. At this point, give up if we've 976 * already tried AUTH_UNIX or if the server's list doesn't contain 977 * AUTH_NULL 978 */ 979 if (tried_auth_unix || !auth_null_in_list) 980 return server; 981 982 /* Last chance! Try AUTH_UNIX */ 983 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX); 984 ctx->selected_flavor = RPC_AUTH_UNIX; 985 return ctx->nfs_mod->rpc_ops->create_server(fc); 986 } 987 988 int nfs_try_get_tree(struct fs_context *fc) 989 { 990 struct nfs_fs_context *ctx = nfs_fc2context(fc); 991 992 if (ctx->need_mount) 993 ctx->server = nfs_try_mount_request(fc); 994 else 995 ctx->server = ctx->nfs_mod->rpc_ops->create_server(fc); 996 997 return nfs_get_tree_common(fc); 998 } 999 EXPORT_SYMBOL_GPL(nfs_try_get_tree); 1000 1001 1002 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \ 1003 | NFS_MOUNT_SECURE \ 1004 | NFS_MOUNT_TCP \ 1005 | NFS_MOUNT_VER3 \ 1006 | NFS_MOUNT_KERBEROS \ 1007 | NFS_MOUNT_NONLM \ 1008 | NFS_MOUNT_BROKEN_SUID \ 1009 | NFS_MOUNT_STRICTLOCK \ 1010 | NFS_MOUNT_LEGACY_INTERFACE) 1011 1012 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \ 1013 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT)) 1014 1015 static int 1016 nfs_compare_remount_data(struct nfs_server *nfss, 1017 struct nfs_fs_context *ctx) 1018 { 1019 if ((ctx->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK || 1020 ctx->rsize != nfss->rsize || 1021 ctx->wsize != nfss->wsize || 1022 ctx->version != nfss->nfs_client->rpc_ops->version || 1023 ctx->minorversion != nfss->nfs_client->cl_minorversion || 1024 ctx->retrans != nfss->client->cl_timeout->to_retries || 1025 !nfs_auth_info_match(&ctx->auth_info, nfss->client->cl_auth->au_flavor) || 1026 ctx->acregmin != nfss->acregmin / HZ || 1027 ctx->acregmax != nfss->acregmax / HZ || 1028 ctx->acdirmin != nfss->acdirmin / HZ || 1029 ctx->acdirmax != nfss->acdirmax / HZ || 1030 ctx->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) || 1031 (ctx->options & NFS_OPTION_FSCACHE) != (nfss->options & NFS_OPTION_FSCACHE) || 1032 ctx->nfs_server.port != nfss->port || 1033 ctx->nfs_server.addrlen != nfss->nfs_client->cl_addrlen || 1034 !rpc_cmp_addr((struct sockaddr *)&ctx->nfs_server.address, 1035 (struct sockaddr *)&nfss->nfs_client->cl_addr)) 1036 return -EINVAL; 1037 1038 return 0; 1039 } 1040 1041 int nfs_reconfigure(struct fs_context *fc) 1042 { 1043 struct nfs_fs_context *ctx = nfs_fc2context(fc); 1044 struct super_block *sb = fc->root->d_sb; 1045 struct nfs_server *nfss = sb->s_fs_info; 1046 int ret; 1047 1048 sync_filesystem(sb); 1049 1050 /* 1051 * Userspace mount programs that send binary options generally send 1052 * them populated with default values. We have no way to know which 1053 * ones were explicitly specified. Fall back to legacy behavior and 1054 * just return success. 1055 */ 1056 if (ctx->skip_reconfig_option_check) 1057 return 0; 1058 1059 /* 1060 * noac is a special case. It implies -o sync, but that's not 1061 * necessarily reflected in the mtab options. reconfigure_super 1062 * will clear SB_SYNCHRONOUS if -o sync wasn't specified in the 1063 * remount options, so we have to explicitly reset it. 1064 */ 1065 if (ctx->flags & NFS_MOUNT_NOAC) { 1066 fc->sb_flags |= SB_SYNCHRONOUS; 1067 fc->sb_flags_mask |= SB_SYNCHRONOUS; 1068 } 1069 1070 /* compare new mount options with old ones */ 1071 ret = nfs_compare_remount_data(nfss, ctx); 1072 if (ret) 1073 return ret; 1074 1075 return nfs_probe_server(nfss, NFS_FH(d_inode(fc->root))); 1076 } 1077 EXPORT_SYMBOL_GPL(nfs_reconfigure); 1078 1079 /* 1080 * Finish setting up an NFS superblock 1081 */ 1082 static void nfs_fill_super(struct super_block *sb, struct nfs_fs_context *ctx) 1083 { 1084 struct nfs_server *server = NFS_SB(sb); 1085 1086 sb->s_blocksize_bits = 0; 1087 sb->s_blocksize = 0; 1088 sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr; 1089 sb->s_op = server->nfs_client->cl_nfs_mod->sops; 1090 if (ctx->bsize) 1091 sb->s_blocksize = nfs_block_size(ctx->bsize, &sb->s_blocksize_bits); 1092 1093 switch (server->nfs_client->rpc_ops->version) { 1094 case 2: 1095 sb->s_time_gran = 1000; 1096 sb->s_time_min = 0; 1097 sb->s_time_max = U32_MAX; 1098 break; 1099 case 3: 1100 /* 1101 * The VFS shouldn't apply the umask to mode bits. 1102 * We will do so ourselves when necessary. 1103 */ 1104 sb->s_flags |= SB_POSIXACL; 1105 sb->s_time_gran = 1; 1106 sb->s_time_min = 0; 1107 sb->s_time_max = U32_MAX; 1108 sb->s_export_op = &nfs_export_ops; 1109 break; 1110 case 4: 1111 sb->s_iflags |= SB_I_NOUMASK; 1112 sb->s_time_gran = 1; 1113 sb->s_time_min = S64_MIN; 1114 sb->s_time_max = S64_MAX; 1115 if (server->caps & NFS_CAP_ATOMIC_OPEN_V1) 1116 sb->s_export_op = &nfs_export_ops; 1117 break; 1118 } 1119 1120 sb->s_magic = NFS_SUPER_MAGIC; 1121 1122 /* We probably want something more informative here */ 1123 snprintf(sb->s_id, sizeof(sb->s_id), 1124 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev)); 1125 1126 if (sb->s_blocksize == 0) 1127 sb->s_blocksize = nfs_block_bits(server->wsize, 1128 &sb->s_blocksize_bits); 1129 1130 nfs_super_set_maxbytes(sb, server->maxfilesize); 1131 nfs_sysfs_move_server_to_sb(sb); 1132 server->has_sec_mnt_opts = ctx->has_sec_mnt_opts; 1133 } 1134 1135 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, 1136 const struct fs_context *fc) 1137 { 1138 const struct nfs_server *a = s->s_fs_info; 1139 const struct rpc_clnt *clnt_a = a->client; 1140 const struct rpc_clnt *clnt_b = b->client; 1141 1142 if ((s->s_flags & NFS_SB_MASK) != (fc->sb_flags & NFS_SB_MASK)) 1143 goto Ebusy; 1144 if (a->nfs_client != b->nfs_client) 1145 goto Ebusy; 1146 if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK) 1147 goto Ebusy; 1148 if (a->wsize != b->wsize) 1149 goto Ebusy; 1150 if (a->rsize != b->rsize) 1151 goto Ebusy; 1152 if (a->acregmin != b->acregmin) 1153 goto Ebusy; 1154 if (a->acregmax != b->acregmax) 1155 goto Ebusy; 1156 if (a->acdirmin != b->acdirmin) 1157 goto Ebusy; 1158 if (a->acdirmax != b->acdirmax) 1159 goto Ebusy; 1160 if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor) 1161 goto Ebusy; 1162 return 1; 1163 Ebusy: 1164 return 0; 1165 } 1166 1167 static int nfs_set_super(struct super_block *s, struct fs_context *fc) 1168 { 1169 struct nfs_server *server = fc->s_fs_info; 1170 int ret; 1171 1172 s->s_d_op = server->nfs_client->rpc_ops->dentry_ops; 1173 ret = set_anon_super(s, server); 1174 if (ret == 0) 1175 server->s_dev = s->s_dev; 1176 return ret; 1177 } 1178 1179 static int nfs_compare_super_address(struct nfs_server *server1, 1180 struct nfs_server *server2) 1181 { 1182 struct sockaddr *sap1, *sap2; 1183 struct rpc_xprt *xprt1 = server1->client->cl_xprt; 1184 struct rpc_xprt *xprt2 = server2->client->cl_xprt; 1185 1186 if (!net_eq(xprt1->xprt_net, xprt2->xprt_net)) 1187 return 0; 1188 1189 sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr; 1190 sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr; 1191 1192 if (sap1->sa_family != sap2->sa_family) 1193 return 0; 1194 1195 switch (sap1->sa_family) { 1196 case AF_INET: { 1197 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1; 1198 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2; 1199 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr) 1200 return 0; 1201 if (sin1->sin_port != sin2->sin_port) 1202 return 0; 1203 break; 1204 } 1205 case AF_INET6: { 1206 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1; 1207 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2; 1208 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr)) 1209 return 0; 1210 if (sin1->sin6_port != sin2->sin6_port) 1211 return 0; 1212 break; 1213 } 1214 default: 1215 return 0; 1216 } 1217 1218 return 1; 1219 } 1220 1221 static int nfs_compare_userns(const struct nfs_server *old, 1222 const struct nfs_server *new) 1223 { 1224 const struct user_namespace *oldns = &init_user_ns; 1225 const struct user_namespace *newns = &init_user_ns; 1226 1227 if (old->client && old->client->cl_cred) 1228 oldns = old->client->cl_cred->user_ns; 1229 if (new->client && new->client->cl_cred) 1230 newns = new->client->cl_cred->user_ns; 1231 if (oldns != newns) 1232 return 0; 1233 return 1; 1234 } 1235 1236 static int nfs_compare_super(struct super_block *sb, struct fs_context *fc) 1237 { 1238 struct nfs_server *server = fc->s_fs_info, *old = NFS_SB(sb); 1239 1240 if (!nfs_compare_super_address(old, server)) 1241 return 0; 1242 /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */ 1243 if (old->flags & NFS_MOUNT_UNSHARED) 1244 return 0; 1245 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0) 1246 return 0; 1247 if (!nfs_compare_userns(old, server)) 1248 return 0; 1249 if ((old->has_sec_mnt_opts || fc->security) && 1250 security_sb_mnt_opts_compat(sb, fc->security)) 1251 return 0; 1252 return nfs_compare_mount_options(sb, server, fc); 1253 } 1254 1255 #ifdef CONFIG_NFS_FSCACHE 1256 static int nfs_get_cache_cookie(struct super_block *sb, 1257 struct nfs_fs_context *ctx) 1258 { 1259 struct nfs_server *nfss = NFS_SB(sb); 1260 char *uniq = NULL; 1261 int ulen = 0; 1262 1263 nfss->fscache = NULL; 1264 1265 if (!ctx) 1266 return 0; 1267 1268 if (ctx->clone_data.sb) { 1269 struct nfs_server *mnt_s = NFS_SB(ctx->clone_data.sb); 1270 if (!(mnt_s->options & NFS_OPTION_FSCACHE)) 1271 return 0; 1272 if (mnt_s->fscache_uniq) { 1273 uniq = mnt_s->fscache_uniq; 1274 ulen = strlen(uniq); 1275 } 1276 } else { 1277 if (!(ctx->options & NFS_OPTION_FSCACHE)) 1278 return 0; 1279 if (ctx->fscache_uniq) { 1280 uniq = ctx->fscache_uniq; 1281 ulen = strlen(ctx->fscache_uniq); 1282 } 1283 } 1284 1285 return nfs_fscache_get_super_cookie(sb, uniq, ulen); 1286 } 1287 #else 1288 static int nfs_get_cache_cookie(struct super_block *sb, 1289 struct nfs_fs_context *ctx) 1290 { 1291 return 0; 1292 } 1293 #endif 1294 1295 int nfs_get_tree_common(struct fs_context *fc) 1296 { 1297 struct nfs_fs_context *ctx = nfs_fc2context(fc); 1298 struct super_block *s; 1299 int (*compare_super)(struct super_block *, struct fs_context *) = nfs_compare_super; 1300 struct nfs_server *server = ctx->server; 1301 int error; 1302 1303 ctx->server = NULL; 1304 if (IS_ERR(server)) 1305 return PTR_ERR(server); 1306 1307 if (server->flags & NFS_MOUNT_UNSHARED) 1308 compare_super = NULL; 1309 1310 /* -o noac implies -o sync */ 1311 if (server->flags & NFS_MOUNT_NOAC) 1312 fc->sb_flags |= SB_SYNCHRONOUS; 1313 1314 if (ctx->clone_data.sb) 1315 if (ctx->clone_data.sb->s_flags & SB_SYNCHRONOUS) 1316 fc->sb_flags |= SB_SYNCHRONOUS; 1317 1318 /* Get a superblock - note that we may end up sharing one that already exists */ 1319 fc->s_fs_info = server; 1320 s = sget_fc(fc, compare_super, nfs_set_super); 1321 fc->s_fs_info = NULL; 1322 if (IS_ERR(s)) { 1323 error = PTR_ERR(s); 1324 nfs_errorf(fc, "NFS: Couldn't get superblock"); 1325 goto out_err_nosb; 1326 } 1327 1328 if (s->s_fs_info != server) { 1329 nfs_free_server(server); 1330 server = NULL; 1331 } else { 1332 error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev), 1333 MINOR(server->s_dev)); 1334 if (error) 1335 goto error_splat_super; 1336 s->s_bdi->io_pages = server->rpages; 1337 server->super = s; 1338 } 1339 1340 if (!s->s_root) { 1341 unsigned bsize = ctx->clone_data.inherited_bsize; 1342 /* initial superblock/root creation */ 1343 nfs_fill_super(s, ctx); 1344 if (bsize) { 1345 s->s_blocksize_bits = bsize; 1346 s->s_blocksize = 1U << bsize; 1347 } 1348 error = nfs_get_cache_cookie(s, ctx); 1349 if (error < 0) 1350 goto error_splat_super; 1351 } 1352 1353 error = nfs_get_root(s, fc); 1354 if (error < 0) { 1355 nfs_errorf(fc, "NFS: Couldn't get root dentry"); 1356 goto error_splat_super; 1357 } 1358 1359 s->s_flags |= SB_ACTIVE; 1360 error = 0; 1361 1362 out: 1363 return error; 1364 1365 out_err_nosb: 1366 nfs_free_server(server); 1367 goto out; 1368 error_splat_super: 1369 deactivate_locked_super(s); 1370 goto out; 1371 } 1372 1373 /* 1374 * Destroy an NFS superblock 1375 */ 1376 void nfs_kill_super(struct super_block *s) 1377 { 1378 struct nfs_server *server = NFS_SB(s); 1379 1380 nfs_sysfs_move_sb_to_server(server); 1381 kill_anon_super(s); 1382 1383 nfs_fscache_release_super_cookie(s); 1384 1385 nfs_free_server(server); 1386 } 1387 EXPORT_SYMBOL_GPL(nfs_kill_super); 1388 1389 #if IS_ENABLED(CONFIG_NFS_V4) 1390 1391 /* 1392 * NFS v4 module parameters need to stay in the 1393 * NFS client for backwards compatibility 1394 */ 1395 unsigned int nfs_callback_set_tcpport; 1396 unsigned short nfs_callback_nr_threads; 1397 /* Default cache timeout is 10 minutes */ 1398 unsigned int nfs_idmap_cache_timeout = 600; 1399 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */ 1400 bool nfs4_disable_idmapping = true; 1401 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE; 1402 unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE; 1403 unsigned short send_implementation_id = 1; 1404 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = ""; 1405 bool recover_lost_locks = false; 1406 short nfs_delay_retrans = -1; 1407 1408 EXPORT_SYMBOL_GPL(nfs_callback_nr_threads); 1409 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport); 1410 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout); 1411 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping); 1412 EXPORT_SYMBOL_GPL(max_session_slots); 1413 EXPORT_SYMBOL_GPL(max_session_cb_slots); 1414 EXPORT_SYMBOL_GPL(send_implementation_id); 1415 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier); 1416 EXPORT_SYMBOL_GPL(recover_lost_locks); 1417 EXPORT_SYMBOL_GPL(nfs_delay_retrans); 1418 1419 #define NFS_CALLBACK_MAXPORTNR (65535U) 1420 1421 static int param_set_portnr(const char *val, const struct kernel_param *kp) 1422 { 1423 unsigned long num; 1424 int ret; 1425 1426 if (!val) 1427 return -EINVAL; 1428 ret = kstrtoul(val, 0, &num); 1429 if (ret || num > NFS_CALLBACK_MAXPORTNR) 1430 return -EINVAL; 1431 *((unsigned int *)kp->arg) = num; 1432 return 0; 1433 } 1434 static const struct kernel_param_ops param_ops_portnr = { 1435 .set = param_set_portnr, 1436 .get = param_get_uint, 1437 }; 1438 #define param_check_portnr(name, p) __param_check(name, p, unsigned int) 1439 1440 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644); 1441 module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644); 1442 MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be " 1443 "assigned to the NFSv4 callback channels."); 1444 module_param(nfs_idmap_cache_timeout, int, 0644); 1445 module_param(nfs4_disable_idmapping, bool, 0644); 1446 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier, 1447 NFS4_CLIENT_ID_UNIQ_LEN, 0600); 1448 MODULE_PARM_DESC(nfs4_disable_idmapping, 1449 "Turn off NFSv4 idmapping when using 'sec=sys'"); 1450 module_param(max_session_slots, ushort, 0644); 1451 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 " 1452 "requests the client will negotiate"); 1453 module_param(max_session_cb_slots, ushort, 0644); 1454 MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 " 1455 "callbacks the client will process for a given server"); 1456 module_param(send_implementation_id, ushort, 0644); 1457 MODULE_PARM_DESC(send_implementation_id, 1458 "Send implementation ID with NFSv4.1 exchange_id"); 1459 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string"); 1460 1461 module_param(recover_lost_locks, bool, 0644); 1462 MODULE_PARM_DESC(recover_lost_locks, 1463 "If the server reports that a lock might be lost, " 1464 "try to recover it risking data corruption."); 1465 1466 module_param_named(delay_retrans, nfs_delay_retrans, short, 0644); 1467 MODULE_PARM_DESC(delay_retrans, 1468 "Unless negative, specifies the number of times the NFSv4 " 1469 "client retries a request before returning an EAGAIN error, " 1470 "after a reply of NFS4ERR_DELAY from the server."); 1471 #endif /* CONFIG_NFS_V4 */ 1472