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 77 #define NFSDBG_FACILITY NFSDBG_VFS 78 79 const struct super_operations nfs_sops = { 80 .alloc_inode = nfs_alloc_inode, 81 .free_inode = nfs_free_inode, 82 .write_inode = nfs_write_inode, 83 .drop_inode = nfs_drop_inode, 84 .statfs = nfs_statfs, 85 .evict_inode = nfs_evict_inode, 86 .umount_begin = nfs_umount_begin, 87 .show_options = nfs_show_options, 88 .show_devname = nfs_show_devname, 89 .show_path = nfs_show_path, 90 .show_stats = nfs_show_stats, 91 }; 92 EXPORT_SYMBOL_GPL(nfs_sops); 93 94 #ifdef CONFIG_NFS_V4_2 95 static const struct nfs_ssc_client_ops nfs_ssc_clnt_ops_tbl = { 96 .sco_sb_deactive = nfs_sb_deactive, 97 }; 98 #endif 99 100 #if IS_ENABLED(CONFIG_NFS_V4) 101 static int __init register_nfs4_fs(void) 102 { 103 return register_filesystem(&nfs4_fs_type); 104 } 105 106 static void unregister_nfs4_fs(void) 107 { 108 unregister_filesystem(&nfs4_fs_type); 109 } 110 #else 111 static int __init register_nfs4_fs(void) 112 { 113 return 0; 114 } 115 116 static void unregister_nfs4_fs(void) 117 { 118 } 119 #endif 120 121 #ifdef CONFIG_NFS_V4_2 122 static void nfs_ssc_register_ops(void) 123 { 124 nfs_ssc_register(&nfs_ssc_clnt_ops_tbl); 125 } 126 127 static void nfs_ssc_unregister_ops(void) 128 { 129 nfs_ssc_unregister(&nfs_ssc_clnt_ops_tbl); 130 } 131 #endif /* CONFIG_NFS_V4_2 */ 132 133 static struct shrinker *acl_shrinker; 134 135 /* 136 * Register the NFS filesystems 137 */ 138 int __init register_nfs_fs(void) 139 { 140 int ret; 141 142 ret = register_filesystem(&nfs_fs_type); 143 if (ret < 0) 144 goto error_0; 145 146 ret = register_nfs4_fs(); 147 if (ret < 0) 148 goto error_1; 149 150 ret = nfs_register_sysctl(); 151 if (ret < 0) 152 goto error_2; 153 154 acl_shrinker = shrinker_alloc(0, "nfs-acl"); 155 if (!acl_shrinker) { 156 ret = -ENOMEM; 157 goto error_3; 158 } 159 160 acl_shrinker->count_objects = nfs_access_cache_count; 161 acl_shrinker->scan_objects = nfs_access_cache_scan; 162 163 shrinker_register(acl_shrinker); 164 165 #ifdef CONFIG_NFS_V4_2 166 nfs_ssc_register_ops(); 167 #endif 168 return 0; 169 error_3: 170 nfs_unregister_sysctl(); 171 error_2: 172 unregister_nfs4_fs(); 173 error_1: 174 unregister_filesystem(&nfs_fs_type); 175 error_0: 176 return ret; 177 } 178 179 /* 180 * Unregister the NFS filesystems 181 */ 182 void __exit unregister_nfs_fs(void) 183 { 184 shrinker_free(acl_shrinker); 185 nfs_unregister_sysctl(); 186 unregister_nfs4_fs(); 187 #ifdef CONFIG_NFS_V4_2 188 nfs_ssc_unregister_ops(); 189 #endif 190 unregister_filesystem(&nfs_fs_type); 191 } 192 193 bool nfs_sb_active(struct super_block *sb) 194 { 195 struct nfs_server *server = NFS_SB(sb); 196 197 if (!atomic_inc_not_zero(&sb->s_active)) 198 return false; 199 if (atomic_inc_return(&server->active) != 1) 200 atomic_dec(&sb->s_active); 201 return true; 202 } 203 EXPORT_SYMBOL_GPL(nfs_sb_active); 204 205 void nfs_sb_deactive(struct super_block *sb) 206 { 207 struct nfs_server *server = NFS_SB(sb); 208 209 if (atomic_dec_and_test(&server->active)) 210 deactivate_super(sb); 211 } 212 EXPORT_SYMBOL_GPL(nfs_sb_deactive); 213 214 static int __nfs_list_for_each_server(struct list_head *head, 215 int (*fn)(struct nfs_server *, void *), 216 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, head, 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 } 241 242 int nfs_client_for_each_server(struct nfs_client *clp, 243 int (*fn)(struct nfs_server *, void *), 244 void *data) 245 { 246 return __nfs_list_for_each_server(&clp->cl_superblocks, fn, data); 247 } 248 EXPORT_SYMBOL_GPL(nfs_client_for_each_server); 249 250 /* 251 * Deliver file system statistics to userspace 252 */ 253 int nfs_statfs(struct dentry *dentry, struct kstatfs *buf) 254 { 255 struct nfs_server *server = NFS_SB(dentry->d_sb); 256 unsigned char blockbits; 257 unsigned long blockres; 258 struct nfs_fh *fh = NFS_FH(d_inode(dentry)); 259 struct nfs_fsstat res; 260 int error = -ENOMEM; 261 262 res.fattr = nfs_alloc_fattr(); 263 if (res.fattr == NULL) 264 goto out_err; 265 266 error = server->nfs_client->rpc_ops->statfs(server, fh, &res); 267 if (unlikely(error == -ESTALE)) { 268 struct dentry *pd_dentry; 269 270 pd_dentry = dget_parent(dentry); 271 nfs_zap_caches(d_inode(pd_dentry)); 272 dput(pd_dentry); 273 } 274 nfs_free_fattr(res.fattr); 275 if (error < 0) 276 goto out_err; 277 278 buf->f_type = NFS_SUPER_MAGIC; 279 280 /* 281 * Current versions of glibc do not correctly handle the 282 * case where f_frsize != f_bsize. Eventually we want to 283 * report the value of wtmult in this field. 284 */ 285 buf->f_frsize = dentry->d_sb->s_blocksize; 286 287 /* 288 * On most *nix systems, f_blocks, f_bfree, and f_bavail 289 * are reported in units of f_frsize. Linux hasn't had 290 * an f_frsize field in its statfs struct until recently, 291 * thus historically Linux's sys_statfs reports these 292 * fields in units of f_bsize. 293 */ 294 buf->f_bsize = dentry->d_sb->s_blocksize; 295 blockbits = dentry->d_sb->s_blocksize_bits; 296 blockres = (1 << blockbits) - 1; 297 buf->f_blocks = (res.tbytes + blockres) >> blockbits; 298 buf->f_bfree = (res.fbytes + blockres) >> blockbits; 299 buf->f_bavail = (res.abytes + blockres) >> blockbits; 300 301 buf->f_files = res.tfiles; 302 buf->f_ffree = res.afiles; 303 304 buf->f_namelen = server->namelen; 305 306 return 0; 307 308 out_err: 309 dprintk("%s: statfs error = %d\n", __func__, -error); 310 return error; 311 } 312 EXPORT_SYMBOL_GPL(nfs_statfs); 313 314 /* 315 * Map the security flavour number to a name 316 */ 317 static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour) 318 { 319 static const struct { 320 rpc_authflavor_t flavour; 321 const char *str; 322 } sec_flavours[NFS_AUTH_INFO_MAX_FLAVORS] = { 323 /* update NFS_AUTH_INFO_MAX_FLAVORS when this list changes! */ 324 { RPC_AUTH_NULL, "null" }, 325 { RPC_AUTH_UNIX, "sys" }, 326 { RPC_AUTH_GSS_KRB5, "krb5" }, 327 { RPC_AUTH_GSS_KRB5I, "krb5i" }, 328 { RPC_AUTH_GSS_KRB5P, "krb5p" }, 329 { RPC_AUTH_GSS_LKEY, "lkey" }, 330 { RPC_AUTH_GSS_LKEYI, "lkeyi" }, 331 { RPC_AUTH_GSS_LKEYP, "lkeyp" }, 332 { RPC_AUTH_GSS_SPKM, "spkm" }, 333 { RPC_AUTH_GSS_SPKMI, "spkmi" }, 334 { RPC_AUTH_GSS_SPKMP, "spkmp" }, 335 { UINT_MAX, "unknown" } 336 }; 337 int i; 338 339 for (i = 0; sec_flavours[i].flavour != UINT_MAX; i++) { 340 if (sec_flavours[i].flavour == flavour) 341 break; 342 } 343 return sec_flavours[i].str; 344 } 345 346 static void nfs_show_mountd_netid(struct seq_file *m, struct nfs_server *nfss, 347 int showdefaults) 348 { 349 struct sockaddr *sap = (struct sockaddr *) &nfss->mountd_address; 350 char *proto = NULL; 351 352 switch (sap->sa_family) { 353 case AF_INET: 354 switch (nfss->mountd_protocol) { 355 case IPPROTO_UDP: 356 proto = RPCBIND_NETID_UDP; 357 break; 358 case IPPROTO_TCP: 359 proto = RPCBIND_NETID_TCP; 360 break; 361 } 362 break; 363 case AF_INET6: 364 switch (nfss->mountd_protocol) { 365 case IPPROTO_UDP: 366 proto = RPCBIND_NETID_UDP6; 367 break; 368 case IPPROTO_TCP: 369 proto = RPCBIND_NETID_TCP6; 370 break; 371 } 372 break; 373 } 374 if (proto || showdefaults) 375 seq_printf(m, ",mountproto=%s", proto ?: "auto"); 376 } 377 378 static void nfs_show_mountd_options(struct seq_file *m, struct nfs_server *nfss, 379 int showdefaults) 380 { 381 struct sockaddr *sap = (struct sockaddr *)&nfss->mountd_address; 382 383 if (nfss->flags & NFS_MOUNT_LEGACY_INTERFACE) 384 return; 385 386 switch (sap->sa_family) { 387 case AF_INET: { 388 struct sockaddr_in *sin = (struct sockaddr_in *)sap; 389 seq_printf(m, ",mountaddr=%pI4", &sin->sin_addr.s_addr); 390 break; 391 } 392 case AF_INET6: { 393 struct sockaddr_in6 *sin6 = (struct sockaddr_in6 *)sap; 394 seq_printf(m, ",mountaddr=%pI6c", &sin6->sin6_addr); 395 break; 396 } 397 default: 398 if (showdefaults) 399 seq_puts(m, ",mountaddr=unspecified"); 400 } 401 402 if (nfss->mountd_version || showdefaults) 403 seq_printf(m, ",mountvers=%u", nfss->mountd_version); 404 if ((nfss->mountd_port && 405 nfss->mountd_port != (unsigned short)NFS_UNSPEC_PORT) || 406 showdefaults) 407 seq_printf(m, ",mountport=%u", nfss->mountd_port); 408 409 nfs_show_mountd_netid(m, nfss, showdefaults); 410 } 411 412 #if IS_ENABLED(CONFIG_NFS_V4) 413 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss, 414 int showdefaults) 415 { 416 struct nfs_client *clp = nfss->nfs_client; 417 418 seq_printf(m, ",clientaddr=%s", clp->cl_ipaddr); 419 } 420 #else 421 static void nfs_show_nfsv4_options(struct seq_file *m, struct nfs_server *nfss, 422 int showdefaults) 423 { 424 } 425 #endif 426 427 static void nfs_show_nfs_version(struct seq_file *m, 428 unsigned int version, 429 unsigned int minorversion) 430 { 431 seq_printf(m, ",vers=%u", version); 432 if (version == 4) 433 seq_printf(m, ".%u", minorversion); 434 } 435 436 /* 437 * Describe the mount options in force on this server representation 438 */ 439 static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, 440 int showdefaults) 441 { 442 static const struct proc_nfs_info { 443 int flag; 444 const char *str; 445 const char *nostr; 446 } nfs_info[] = { 447 { NFS_MOUNT_SOFT, ",soft", "" }, 448 { NFS_MOUNT_SOFTERR, ",softerr", "" }, 449 { NFS_MOUNT_SOFTREVAL, ",softreval", "" }, 450 { NFS_MOUNT_POSIX, ",posix", "" }, 451 { NFS_MOUNT_NOCTO, ",nocto", "" }, 452 { NFS_MOUNT_NOAC, ",noac", "" }, 453 { NFS_MOUNT_NONLM, ",nolock", "" }, 454 { NFS_MOUNT_NOACL, ",noacl", "" }, 455 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" }, 456 { NFS_MOUNT_UNSHARED, ",nosharecache", "" }, 457 { NFS_MOUNT_NORESVPORT, ",noresvport", "" }, 458 { 0, NULL, NULL } 459 }; 460 const struct proc_nfs_info *nfs_infop; 461 struct nfs_client *clp = nfss->nfs_client; 462 u32 version = clp->rpc_ops->version; 463 int local_flock, local_fcntl; 464 465 nfs_show_nfs_version(m, version, clp->cl_minorversion); 466 seq_printf(m, ",rsize=%u", nfss->rsize); 467 seq_printf(m, ",wsize=%u", nfss->wsize); 468 if (nfss->bsize != 0) 469 seq_printf(m, ",bsize=%u", nfss->bsize); 470 seq_printf(m, ",namlen=%u", nfss->namelen); 471 if (nfss->acregmin != NFS_DEF_ACREGMIN*HZ || showdefaults) 472 seq_printf(m, ",acregmin=%u", nfss->acregmin/HZ); 473 if (nfss->acregmax != NFS_DEF_ACREGMAX*HZ || showdefaults) 474 seq_printf(m, ",acregmax=%u", nfss->acregmax/HZ); 475 if (nfss->acdirmin != NFS_DEF_ACDIRMIN*HZ || showdefaults) 476 seq_printf(m, ",acdirmin=%u", nfss->acdirmin/HZ); 477 if (nfss->acdirmax != NFS_DEF_ACDIRMAX*HZ || showdefaults) 478 seq_printf(m, ",acdirmax=%u", nfss->acdirmax/HZ); 479 if (!(nfss->flags & (NFS_MOUNT_SOFT|NFS_MOUNT_SOFTERR))) 480 seq_puts(m, ",hard"); 481 for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) { 482 if (nfss->flags & nfs_infop->flag) 483 seq_puts(m, nfs_infop->str); 484 else 485 seq_puts(m, nfs_infop->nostr); 486 } 487 rcu_read_lock(); 488 seq_printf(m, ",proto=%s", 489 rpc_peeraddr2str(nfss->client, RPC_DISPLAY_NETID)); 490 rcu_read_unlock(); 491 if (clp->cl_nconnect > 0) 492 seq_printf(m, ",nconnect=%u", clp->cl_nconnect); 493 if (version == 4) { 494 if (clp->cl_max_connect > 1) 495 seq_printf(m, ",max_connect=%u", clp->cl_max_connect); 496 if (nfss->port != NFS_PORT) 497 seq_printf(m, ",port=%u", nfss->port); 498 } else 499 if (nfss->port) 500 seq_printf(m, ",port=%u", nfss->port); 501 502 seq_printf(m, ",timeo=%lu", 10U * nfss->client->cl_timeout->to_initval / HZ); 503 seq_printf(m, ",retrans=%u", nfss->client->cl_timeout->to_retries); 504 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor)); 505 switch (clp->cl_xprtsec.policy) { 506 case RPC_XPRTSEC_TLS_ANON: 507 seq_puts(m, ",xprtsec=tls"); 508 break; 509 case RPC_XPRTSEC_TLS_X509: 510 seq_puts(m, ",xprtsec=mtls"); 511 break; 512 default: 513 break; 514 } 515 516 if (version != 4) 517 nfs_show_mountd_options(m, nfss, showdefaults); 518 else 519 nfs_show_nfsv4_options(m, nfss, showdefaults); 520 521 if (nfss->options & NFS_OPTION_FSCACHE) { 522 #ifdef CONFIG_NFS_FSCACHE 523 if (nfss->fscache_uniq) 524 seq_printf(m, ",fsc=%s", nfss->fscache_uniq); 525 else 526 seq_puts(m, ",fsc"); 527 #else 528 seq_puts(m, ",fsc"); 529 #endif 530 } 531 532 if (nfss->options & NFS_OPTION_MIGRATION) 533 seq_puts(m, ",migration"); 534 535 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG) { 536 if (nfss->flags & NFS_MOUNT_LOOKUP_CACHE_NONE) 537 seq_puts(m, ",lookupcache=none"); 538 else 539 seq_puts(m, ",lookupcache=pos"); 540 } 541 542 local_flock = nfss->flags & NFS_MOUNT_LOCAL_FLOCK; 543 local_fcntl = nfss->flags & NFS_MOUNT_LOCAL_FCNTL; 544 545 if (!local_flock && !local_fcntl) 546 seq_puts(m, ",local_lock=none"); 547 else if (local_flock && local_fcntl) 548 seq_puts(m, ",local_lock=all"); 549 else if (local_flock) 550 seq_puts(m, ",local_lock=flock"); 551 else 552 seq_puts(m, ",local_lock=posix"); 553 554 if (nfss->flags & NFS_MOUNT_NO_ALIGNWRITE) 555 seq_puts(m, ",noalignwrite"); 556 557 if (nfss->flags & NFS_MOUNT_WRITE_EAGER) { 558 if (nfss->flags & NFS_MOUNT_WRITE_WAIT) 559 seq_puts(m, ",write=wait"); 560 else 561 seq_puts(m, ",write=eager"); 562 } 563 } 564 565 /* 566 * Describe the mount options on this VFS mountpoint 567 */ 568 int nfs_show_options(struct seq_file *m, struct dentry *root) 569 { 570 struct nfs_server *nfss = NFS_SB(root->d_sb); 571 572 nfs_show_mount_options(m, nfss, 0); 573 574 rcu_read_lock(); 575 seq_printf(m, ",addr=%s", 576 rpc_peeraddr2str(nfss->nfs_client->cl_rpcclient, 577 RPC_DISPLAY_ADDR)); 578 rcu_read_unlock(); 579 580 return 0; 581 } 582 EXPORT_SYMBOL_GPL(nfs_show_options); 583 584 #if IS_ENABLED(CONFIG_NFS_V4) 585 static void show_lease(struct seq_file *m, struct nfs_server *server) 586 { 587 struct nfs_client *clp = server->nfs_client; 588 unsigned long expire; 589 590 seq_printf(m, ",lease_time=%ld", clp->cl_lease_time / HZ); 591 expire = clp->cl_last_renewal + clp->cl_lease_time; 592 seq_printf(m, ",lease_expired=%ld", 593 time_after(expire, jiffies) ? 0 : (jiffies - expire) / HZ); 594 } 595 #ifdef CONFIG_NFS_V4_1 596 static void show_sessions(struct seq_file *m, struct nfs_server *server) 597 { 598 if (nfs4_has_session(server->nfs_client)) 599 seq_puts(m, ",sessions"); 600 } 601 #else 602 static void show_sessions(struct seq_file *m, struct nfs_server *server) {} 603 #endif 604 #endif 605 606 #ifdef CONFIG_NFS_V4_1 607 static void show_pnfs(struct seq_file *m, struct nfs_server *server) 608 { 609 seq_printf(m, ",pnfs="); 610 if (server->pnfs_curr_ld) 611 seq_printf(m, "%s", server->pnfs_curr_ld->name); 612 else 613 seq_printf(m, "not configured"); 614 } 615 616 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss) 617 { 618 if (nfss->nfs_client && nfss->nfs_client->cl_implid) { 619 struct nfs41_impl_id *impl_id = nfss->nfs_client->cl_implid; 620 seq_printf(m, "\n\timpl_id:\tname='%s',domain='%s'," 621 "date='%llu,%u'", 622 impl_id->name, impl_id->domain, 623 impl_id->date.seconds, impl_id->date.nseconds); 624 } 625 } 626 #else 627 #if IS_ENABLED(CONFIG_NFS_V4) 628 static void show_pnfs(struct seq_file *m, struct nfs_server *server) 629 { 630 } 631 #endif 632 static void show_implementation_id(struct seq_file *m, struct nfs_server *nfss) 633 { 634 } 635 #endif 636 637 int nfs_show_devname(struct seq_file *m, struct dentry *root) 638 { 639 char *page = (char *) __get_free_page(GFP_KERNEL); 640 char *devname, *dummy; 641 int err = 0; 642 if (!page) 643 return -ENOMEM; 644 devname = nfs_path(&dummy, root, page, PAGE_SIZE, 0); 645 if (IS_ERR(devname)) 646 err = PTR_ERR(devname); 647 else 648 seq_escape(m, devname, " \t\n\\"); 649 free_page((unsigned long)page); 650 return err; 651 } 652 EXPORT_SYMBOL_GPL(nfs_show_devname); 653 654 int nfs_show_path(struct seq_file *m, struct dentry *dentry) 655 { 656 seq_puts(m, "/"); 657 return 0; 658 } 659 EXPORT_SYMBOL_GPL(nfs_show_path); 660 661 /* 662 * Present statistical information for this VFS mountpoint 663 */ 664 int nfs_show_stats(struct seq_file *m, struct dentry *root) 665 { 666 int i, cpu; 667 struct nfs_server *nfss = NFS_SB(root->d_sb); 668 struct rpc_auth *auth = nfss->client->cl_auth; 669 struct nfs_iostats totals = { }; 670 671 seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS); 672 673 /* 674 * Display all mount option settings 675 */ 676 seq_puts(m, "\n\topts:\t"); 677 seq_puts(m, sb_rdonly(root->d_sb) ? "ro" : "rw"); 678 seq_puts(m, root->d_sb->s_flags & SB_SYNCHRONOUS ? ",sync" : ""); 679 seq_puts(m, root->d_sb->s_flags & SB_NOATIME ? ",noatime" : ""); 680 seq_puts(m, root->d_sb->s_flags & SB_NODIRATIME ? ",nodiratime" : ""); 681 nfs_show_mount_options(m, nfss, 1); 682 683 seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ); 684 685 show_implementation_id(m, nfss); 686 687 seq_puts(m, "\n\tcaps:\t"); 688 seq_printf(m, "caps=0x%x", nfss->caps); 689 seq_printf(m, ",wtmult=%u", nfss->wtmult); 690 seq_printf(m, ",dtsize=%u", nfss->dtsize); 691 seq_printf(m, ",bsize=%u", nfss->bsize); 692 seq_printf(m, ",namlen=%u", nfss->namelen); 693 694 #if IS_ENABLED(CONFIG_NFS_V4) 695 if (nfss->nfs_client->rpc_ops->version == 4) { 696 seq_puts(m, "\n\tnfsv4:\t"); 697 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]); 698 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]); 699 seq_printf(m, ",bm2=0x%x", nfss->attr_bitmask[2]); 700 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask); 701 show_sessions(m, nfss); 702 show_pnfs(m, nfss); 703 show_lease(m, nfss); 704 } 705 #endif 706 707 /* 708 * Display security flavor in effect for this mount 709 */ 710 seq_printf(m, "\n\tsec:\tflavor=%u", auth->au_ops->au_flavor); 711 if (auth->au_flavor) 712 seq_printf(m, ",pseudoflavor=%u", auth->au_flavor); 713 714 /* 715 * Display superblock I/O counters 716 */ 717 for_each_possible_cpu(cpu) { 718 struct nfs_iostats *stats; 719 720 preempt_disable(); 721 stats = per_cpu_ptr(nfss->io_stats, cpu); 722 723 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 724 totals.events[i] += stats->events[i]; 725 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 726 totals.bytes[i] += stats->bytes[i]; 727 728 preempt_enable(); 729 } 730 731 seq_puts(m, "\n\tevents:\t"); 732 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 733 seq_printf(m, "%lu ", totals.events[i]); 734 seq_puts(m, "\n\tbytes:\t"); 735 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 736 seq_printf(m, "%Lu ", totals.bytes[i]); 737 seq_putc(m, '\n'); 738 739 rpc_clnt_show_stats(m, nfss->client); 740 741 return 0; 742 } 743 EXPORT_SYMBOL_GPL(nfs_show_stats); 744 745 /* 746 * Begin unmount by attempting to remove all automounted mountpoints we added 747 * in response to xdev traversals and referrals 748 */ 749 void nfs_umount_begin(struct super_block *sb) 750 { 751 struct nfs_server *server; 752 struct rpc_clnt *rpc; 753 754 server = NFS_SB(sb); 755 /* -EIO all pending I/O */ 756 rpc = server->client_acl; 757 if (!IS_ERR(rpc)) 758 rpc_killall_tasks(rpc); 759 rpc = server->client; 760 if (!IS_ERR(rpc)) 761 rpc_killall_tasks(rpc); 762 } 763 EXPORT_SYMBOL_GPL(nfs_umount_begin); 764 765 /* 766 * Return true if 'match' is in auth_info or auth_info is empty. 767 * Return false otherwise. 768 */ 769 bool nfs_auth_info_match(const struct nfs_auth_info *auth_info, 770 rpc_authflavor_t match) 771 { 772 int i; 773 774 if (!auth_info->flavor_len) 775 return true; 776 777 for (i = 0; i < auth_info->flavor_len; i++) { 778 if (auth_info->flavors[i] == match) 779 return true; 780 } 781 return false; 782 } 783 EXPORT_SYMBOL_GPL(nfs_auth_info_match); 784 785 /* 786 * Ensure that a specified authtype in ctx->auth_info is supported by 787 * the server. Returns 0 and sets ctx->selected_flavor if it's ok, and 788 * -EACCES if not. 789 */ 790 static int nfs_verify_authflavors(struct nfs_fs_context *ctx, 791 rpc_authflavor_t *server_authlist, 792 unsigned int count) 793 { 794 rpc_authflavor_t flavor = RPC_AUTH_MAXFLAVOR; 795 bool found_auth_null = false; 796 unsigned int i; 797 798 /* 799 * If the sec= mount option is used, the specified flavor or AUTH_NULL 800 * must be in the list returned by the server. 801 * 802 * AUTH_NULL has a special meaning when it's in the server list - it 803 * means that the server will ignore the rpc creds, so any flavor 804 * can be used but still use the sec= that was specified. 805 * 806 * Note also that the MNT procedure in MNTv1 does not return a list 807 * of supported security flavors. In this case, nfs_mount() fabricates 808 * a security flavor list containing just AUTH_NULL. 809 */ 810 for (i = 0; i < count; i++) { 811 flavor = server_authlist[i]; 812 813 if (nfs_auth_info_match(&ctx->auth_info, flavor)) 814 goto out; 815 816 if (flavor == RPC_AUTH_NULL) 817 found_auth_null = true; 818 } 819 820 if (found_auth_null) { 821 flavor = ctx->auth_info.flavors[0]; 822 goto out; 823 } 824 825 dfprintk(MOUNT, 826 "NFS: specified auth flavors not supported by server\n"); 827 return -EACCES; 828 829 out: 830 ctx->selected_flavor = flavor; 831 dfprintk(MOUNT, "NFS: using auth flavor %u\n", ctx->selected_flavor); 832 return 0; 833 } 834 835 /* 836 * Use the remote server's MOUNT service to request the NFS file handle 837 * corresponding to the provided path. 838 */ 839 static int nfs_request_mount(struct fs_context *fc, 840 struct nfs_fh *root_fh, 841 rpc_authflavor_t *server_authlist, 842 unsigned int *server_authlist_len) 843 { 844 struct nfs_fs_context *ctx = nfs_fc2context(fc); 845 struct nfs_mount_request request = { 846 .sap = &ctx->mount_server._address, 847 .dirpath = ctx->nfs_server.export_path, 848 .protocol = ctx->mount_server.protocol, 849 .fh = root_fh, 850 .noresvport = ctx->flags & NFS_MOUNT_NORESVPORT, 851 .auth_flav_len = server_authlist_len, 852 .auth_flavs = server_authlist, 853 .net = fc->net_ns, 854 }; 855 int status; 856 857 if (ctx->mount_server.version == 0) { 858 switch (ctx->version) { 859 default: 860 ctx->mount_server.version = NFS_MNT3_VERSION; 861 break; 862 case 2: 863 ctx->mount_server.version = NFS_MNT_VERSION; 864 } 865 } 866 request.version = ctx->mount_server.version; 867 868 if (ctx->mount_server.hostname) 869 request.hostname = ctx->mount_server.hostname; 870 else 871 request.hostname = ctx->nfs_server.hostname; 872 873 /* 874 * Construct the mount server's address. 875 */ 876 if (ctx->mount_server.address.sa_family == AF_UNSPEC) { 877 memcpy(request.sap, &ctx->nfs_server._address, 878 ctx->nfs_server.addrlen); 879 ctx->mount_server.addrlen = ctx->nfs_server.addrlen; 880 } 881 request.salen = ctx->mount_server.addrlen; 882 nfs_set_port(request.sap, &ctx->mount_server.port, 0); 883 884 /* 885 * Now ask the mount server to map our export path 886 * to a file handle. 887 */ 888 if ((request.protocol == XPRT_TRANSPORT_UDP) == 889 !(ctx->flags & NFS_MOUNT_TCP)) 890 /* 891 * NFS protocol and mount protocol are both UDP or neither UDP 892 * so timeouts are compatible. Use NFS timeouts for MOUNT 893 */ 894 status = nfs_mount(&request, ctx->timeo, ctx->retrans); 895 else 896 status = nfs_mount(&request, NFS_UNSPEC_TIMEO, NFS_UNSPEC_RETRANS); 897 if (status != 0) { 898 dfprintk(MOUNT, "NFS: unable to mount server %s, error %d\n", 899 request.hostname, status); 900 return status; 901 } 902 903 return 0; 904 } 905 906 static struct nfs_server *nfs_try_mount_request(struct fs_context *fc) 907 { 908 struct nfs_fs_context *ctx = nfs_fc2context(fc); 909 int status; 910 unsigned int i; 911 bool tried_auth_unix = false; 912 bool auth_null_in_list = false; 913 struct nfs_server *server = ERR_PTR(-EACCES); 914 rpc_authflavor_t authlist[NFS_MAX_SECFLAVORS]; 915 unsigned int authlist_len = ARRAY_SIZE(authlist); 916 917 /* make sure 'nolock'/'lock' override the 'local_lock' mount option */ 918 if (ctx->lock_status) { 919 if (ctx->lock_status == NFS_LOCK_NOLOCK) { 920 ctx->flags |= NFS_MOUNT_NONLM; 921 ctx->flags |= (NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL); 922 } else { 923 ctx->flags &= ~NFS_MOUNT_NONLM; 924 ctx->flags &= ~(NFS_MOUNT_LOCAL_FLOCK | NFS_MOUNT_LOCAL_FCNTL); 925 } 926 } 927 status = nfs_request_mount(fc, ctx->mntfh, authlist, &authlist_len); 928 if (status) 929 return ERR_PTR(status); 930 931 /* 932 * Was a sec= authflavor specified in the options? First, verify 933 * whether the server supports it, and then just try to use it if so. 934 */ 935 if (ctx->auth_info.flavor_len > 0) { 936 status = nfs_verify_authflavors(ctx, authlist, authlist_len); 937 dfprintk(MOUNT, "NFS: using auth flavor %u\n", 938 ctx->selected_flavor); 939 if (status) 940 return ERR_PTR(status); 941 return ctx->nfs_mod->rpc_ops->create_server(fc); 942 } 943 944 /* 945 * No sec= option was provided. RFC 2623, section 2.7 suggests we 946 * SHOULD prefer the flavor listed first. However, some servers list 947 * AUTH_NULL first. Avoid ever choosing AUTH_NULL. 948 */ 949 for (i = 0; i < authlist_len; ++i) { 950 rpc_authflavor_t flavor; 951 struct rpcsec_gss_info info; 952 953 flavor = authlist[i]; 954 switch (flavor) { 955 case RPC_AUTH_UNIX: 956 tried_auth_unix = true; 957 break; 958 case RPC_AUTH_NULL: 959 auth_null_in_list = true; 960 continue; 961 default: 962 if (rpcauth_get_gssinfo(flavor, &info) != 0) 963 continue; 964 break; 965 } 966 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", flavor); 967 ctx->selected_flavor = flavor; 968 server = ctx->nfs_mod->rpc_ops->create_server(fc); 969 if (!IS_ERR(server)) 970 return server; 971 } 972 973 /* 974 * Nothing we tried so far worked. At this point, give up if we've 975 * already tried AUTH_UNIX or if the server's list doesn't contain 976 * AUTH_NULL 977 */ 978 if (tried_auth_unix || !auth_null_in_list) 979 return server; 980 981 /* Last chance! Try AUTH_UNIX */ 982 dfprintk(MOUNT, "NFS: attempting to use auth flavor %u\n", RPC_AUTH_UNIX); 983 ctx->selected_flavor = RPC_AUTH_UNIX; 984 return ctx->nfs_mod->rpc_ops->create_server(fc); 985 } 986 987 int nfs_try_get_tree(struct fs_context *fc) 988 { 989 struct nfs_fs_context *ctx = nfs_fc2context(fc); 990 991 if (ctx->need_mount) 992 ctx->server = nfs_try_mount_request(fc); 993 else 994 ctx->server = ctx->nfs_mod->rpc_ops->create_server(fc); 995 996 return nfs_get_tree_common(fc); 997 } 998 EXPORT_SYMBOL_GPL(nfs_try_get_tree); 999 1000 1001 #define NFS_REMOUNT_CMP_FLAGMASK ~(NFS_MOUNT_INTR \ 1002 | NFS_MOUNT_SECURE \ 1003 | NFS_MOUNT_TCP \ 1004 | NFS_MOUNT_VER3 \ 1005 | NFS_MOUNT_KERBEROS \ 1006 | NFS_MOUNT_NONLM \ 1007 | NFS_MOUNT_BROKEN_SUID \ 1008 | NFS_MOUNT_STRICTLOCK \ 1009 | NFS_MOUNT_LEGACY_INTERFACE) 1010 1011 #define NFS_MOUNT_CMP_FLAGMASK (NFS_REMOUNT_CMP_FLAGMASK & \ 1012 ~(NFS_MOUNT_UNSHARED | NFS_MOUNT_NORESVPORT)) 1013 1014 static int 1015 nfs_compare_remount_data(struct nfs_server *nfss, 1016 struct nfs_fs_context *ctx) 1017 { 1018 if ((ctx->flags ^ nfss->flags) & NFS_REMOUNT_CMP_FLAGMASK || 1019 ctx->rsize != nfss->rsize || 1020 ctx->wsize != nfss->wsize || 1021 ctx->version != nfss->nfs_client->rpc_ops->version || 1022 ctx->minorversion != nfss->nfs_client->cl_minorversion || 1023 ctx->retrans != nfss->client->cl_timeout->to_retries || 1024 !nfs_auth_info_match(&ctx->auth_info, nfss->client->cl_auth->au_flavor) || 1025 ctx->acregmin != nfss->acregmin / HZ || 1026 ctx->acregmax != nfss->acregmax / HZ || 1027 ctx->acdirmin != nfss->acdirmin / HZ || 1028 ctx->acdirmax != nfss->acdirmax / HZ || 1029 ctx->timeo != (10U * nfss->client->cl_timeout->to_initval / HZ) || 1030 (ctx->options & NFS_OPTION_FSCACHE) != (nfss->options & NFS_OPTION_FSCACHE) || 1031 ctx->nfs_server.port != nfss->port || 1032 ctx->nfs_server.addrlen != nfss->nfs_client->cl_addrlen || 1033 !rpc_cmp_addr((struct sockaddr *)&ctx->nfs_server.address, 1034 (struct sockaddr *)&nfss->nfs_client->cl_addr)) 1035 return -EINVAL; 1036 1037 return 0; 1038 } 1039 1040 int nfs_reconfigure(struct fs_context *fc) 1041 { 1042 struct nfs_fs_context *ctx = nfs_fc2context(fc); 1043 struct super_block *sb = fc->root->d_sb; 1044 struct nfs_server *nfss = sb->s_fs_info; 1045 int ret; 1046 1047 sync_filesystem(sb); 1048 1049 /* 1050 * Userspace mount programs that send binary options generally send 1051 * them populated with default values. We have no way to know which 1052 * ones were explicitly specified. Fall back to legacy behavior and 1053 * just return success. 1054 */ 1055 if (ctx->skip_reconfig_option_check) 1056 return 0; 1057 1058 /* 1059 * noac is a special case. It implies -o sync, but that's not 1060 * necessarily reflected in the mtab options. reconfigure_super 1061 * will clear SB_SYNCHRONOUS if -o sync wasn't specified in the 1062 * remount options, so we have to explicitly reset it. 1063 */ 1064 if (ctx->flags & NFS_MOUNT_NOAC) { 1065 fc->sb_flags |= SB_SYNCHRONOUS; 1066 fc->sb_flags_mask |= SB_SYNCHRONOUS; 1067 } 1068 1069 /* compare new mount options with old ones */ 1070 ret = nfs_compare_remount_data(nfss, ctx); 1071 if (ret) 1072 return ret; 1073 1074 return nfs_probe_server(nfss, NFS_FH(d_inode(fc->root))); 1075 } 1076 EXPORT_SYMBOL_GPL(nfs_reconfigure); 1077 1078 /* 1079 * Finish setting up an NFS superblock 1080 */ 1081 static void nfs_fill_super(struct super_block *sb, struct nfs_fs_context *ctx) 1082 { 1083 struct nfs_server *server = NFS_SB(sb); 1084 1085 sb->s_blocksize_bits = 0; 1086 sb->s_blocksize = 0; 1087 sb->s_xattr = server->nfs_client->cl_nfs_mod->xattr; 1088 sb->s_op = server->nfs_client->cl_nfs_mod->sops; 1089 if (ctx->bsize) 1090 sb->s_blocksize = nfs_block_size(ctx->bsize, &sb->s_blocksize_bits); 1091 1092 switch (server->nfs_client->rpc_ops->version) { 1093 case 2: 1094 sb->s_time_gran = 1000; 1095 sb->s_time_min = 0; 1096 sb->s_time_max = U32_MAX; 1097 break; 1098 case 3: 1099 /* 1100 * The VFS shouldn't apply the umask to mode bits. 1101 * We will do so ourselves when necessary. 1102 */ 1103 sb->s_flags |= SB_POSIXACL; 1104 sb->s_time_gran = 1; 1105 sb->s_time_min = 0; 1106 sb->s_time_max = U32_MAX; 1107 sb->s_export_op = &nfs_export_ops; 1108 break; 1109 case 4: 1110 sb->s_iflags |= SB_I_NOUMASK; 1111 sb->s_time_gran = 1; 1112 sb->s_time_min = S64_MIN; 1113 sb->s_time_max = S64_MAX; 1114 if (server->caps & NFS_CAP_ATOMIC_OPEN_V1) 1115 sb->s_export_op = &nfs_export_ops; 1116 break; 1117 } 1118 1119 sb->s_magic = NFS_SUPER_MAGIC; 1120 1121 /* We probably want something more informative here */ 1122 snprintf(sb->s_id, sizeof(sb->s_id), 1123 "%u:%u", MAJOR(sb->s_dev), MINOR(sb->s_dev)); 1124 1125 if (sb->s_blocksize == 0) 1126 sb->s_blocksize = nfs_block_bits(server->wsize, 1127 &sb->s_blocksize_bits); 1128 1129 nfs_super_set_maxbytes(sb, server->maxfilesize); 1130 nfs_sysfs_move_server_to_sb(sb); 1131 server->has_sec_mnt_opts = ctx->has_sec_mnt_opts; 1132 } 1133 1134 static int nfs_compare_mount_options(const struct super_block *s, const struct nfs_server *b, 1135 const struct fs_context *fc) 1136 { 1137 const struct nfs_server *a = s->s_fs_info; 1138 const struct rpc_clnt *clnt_a = a->client; 1139 const struct rpc_clnt *clnt_b = b->client; 1140 1141 if ((s->s_flags & NFS_SB_MASK) != (fc->sb_flags & NFS_SB_MASK)) 1142 goto Ebusy; 1143 if (a->nfs_client != b->nfs_client) 1144 goto Ebusy; 1145 if ((a->flags ^ b->flags) & NFS_MOUNT_CMP_FLAGMASK) 1146 goto Ebusy; 1147 if (a->wsize != b->wsize) 1148 goto Ebusy; 1149 if (a->rsize != b->rsize) 1150 goto Ebusy; 1151 if (a->acregmin != b->acregmin) 1152 goto Ebusy; 1153 if (a->acregmax != b->acregmax) 1154 goto Ebusy; 1155 if (a->acdirmin != b->acdirmin) 1156 goto Ebusy; 1157 if (a->acdirmax != b->acdirmax) 1158 goto Ebusy; 1159 if (clnt_a->cl_auth->au_flavor != clnt_b->cl_auth->au_flavor) 1160 goto Ebusy; 1161 return 1; 1162 Ebusy: 1163 return 0; 1164 } 1165 1166 static int nfs_set_super(struct super_block *s, struct fs_context *fc) 1167 { 1168 struct nfs_server *server = fc->s_fs_info; 1169 int ret; 1170 1171 s->s_d_op = server->nfs_client->rpc_ops->dentry_ops; 1172 ret = set_anon_super(s, server); 1173 if (ret == 0) 1174 server->s_dev = s->s_dev; 1175 return ret; 1176 } 1177 1178 static int nfs_compare_super_address(struct nfs_server *server1, 1179 struct nfs_server *server2) 1180 { 1181 struct sockaddr *sap1, *sap2; 1182 struct rpc_xprt *xprt1 = server1->client->cl_xprt; 1183 struct rpc_xprt *xprt2 = server2->client->cl_xprt; 1184 1185 if (!net_eq(xprt1->xprt_net, xprt2->xprt_net)) 1186 return 0; 1187 1188 sap1 = (struct sockaddr *)&server1->nfs_client->cl_addr; 1189 sap2 = (struct sockaddr *)&server2->nfs_client->cl_addr; 1190 1191 if (sap1->sa_family != sap2->sa_family) 1192 return 0; 1193 1194 switch (sap1->sa_family) { 1195 case AF_INET: { 1196 struct sockaddr_in *sin1 = (struct sockaddr_in *)sap1; 1197 struct sockaddr_in *sin2 = (struct sockaddr_in *)sap2; 1198 if (sin1->sin_addr.s_addr != sin2->sin_addr.s_addr) 1199 return 0; 1200 if (sin1->sin_port != sin2->sin_port) 1201 return 0; 1202 break; 1203 } 1204 case AF_INET6: { 1205 struct sockaddr_in6 *sin1 = (struct sockaddr_in6 *)sap1; 1206 struct sockaddr_in6 *sin2 = (struct sockaddr_in6 *)sap2; 1207 if (!ipv6_addr_equal(&sin1->sin6_addr, &sin2->sin6_addr)) 1208 return 0; 1209 if (sin1->sin6_port != sin2->sin6_port) 1210 return 0; 1211 break; 1212 } 1213 default: 1214 return 0; 1215 } 1216 1217 return 1; 1218 } 1219 1220 static int nfs_compare_userns(const struct nfs_server *old, 1221 const struct nfs_server *new) 1222 { 1223 const struct user_namespace *oldns = &init_user_ns; 1224 const struct user_namespace *newns = &init_user_ns; 1225 1226 if (old->client && old->client->cl_cred) 1227 oldns = old->client->cl_cred->user_ns; 1228 if (new->client && new->client->cl_cred) 1229 newns = new->client->cl_cred->user_ns; 1230 if (oldns != newns) 1231 return 0; 1232 return 1; 1233 } 1234 1235 static int nfs_compare_super(struct super_block *sb, struct fs_context *fc) 1236 { 1237 struct nfs_server *server = fc->s_fs_info, *old = NFS_SB(sb); 1238 1239 if (!nfs_compare_super_address(old, server)) 1240 return 0; 1241 /* Note: NFS_MOUNT_UNSHARED == NFS4_MOUNT_UNSHARED */ 1242 if (old->flags & NFS_MOUNT_UNSHARED) 1243 return 0; 1244 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0) 1245 return 0; 1246 if (!nfs_compare_userns(old, server)) 1247 return 0; 1248 if ((old->has_sec_mnt_opts || fc->security) && 1249 security_sb_mnt_opts_compat(sb, fc->security)) 1250 return 0; 1251 return nfs_compare_mount_options(sb, server, fc); 1252 } 1253 1254 #ifdef CONFIG_NFS_FSCACHE 1255 static int nfs_get_cache_cookie(struct super_block *sb, 1256 struct nfs_fs_context *ctx) 1257 { 1258 struct nfs_server *nfss = NFS_SB(sb); 1259 char *uniq = NULL; 1260 int ulen = 0; 1261 1262 nfss->fscache = NULL; 1263 1264 if (!ctx) 1265 return 0; 1266 1267 if (ctx->clone_data.sb) { 1268 struct nfs_server *mnt_s = NFS_SB(ctx->clone_data.sb); 1269 if (!(mnt_s->options & NFS_OPTION_FSCACHE)) 1270 return 0; 1271 if (mnt_s->fscache_uniq) { 1272 uniq = mnt_s->fscache_uniq; 1273 ulen = strlen(uniq); 1274 } 1275 } else { 1276 if (!(ctx->options & NFS_OPTION_FSCACHE)) 1277 return 0; 1278 if (ctx->fscache_uniq) { 1279 uniq = ctx->fscache_uniq; 1280 ulen = strlen(ctx->fscache_uniq); 1281 } 1282 } 1283 1284 return nfs_fscache_get_super_cookie(sb, uniq, ulen); 1285 } 1286 #else 1287 static int nfs_get_cache_cookie(struct super_block *sb, 1288 struct nfs_fs_context *ctx) 1289 { 1290 return 0; 1291 } 1292 #endif 1293 1294 int nfs_get_tree_common(struct fs_context *fc) 1295 { 1296 struct nfs_fs_context *ctx = nfs_fc2context(fc); 1297 struct super_block *s; 1298 int (*compare_super)(struct super_block *, struct fs_context *) = nfs_compare_super; 1299 struct nfs_server *server = ctx->server; 1300 int error; 1301 1302 ctx->server = NULL; 1303 if (IS_ERR(server)) 1304 return PTR_ERR(server); 1305 1306 if (server->flags & NFS_MOUNT_UNSHARED) 1307 compare_super = NULL; 1308 1309 /* -o noac implies -o sync */ 1310 if (server->flags & NFS_MOUNT_NOAC) 1311 fc->sb_flags |= SB_SYNCHRONOUS; 1312 1313 if (ctx->clone_data.sb) 1314 if (ctx->clone_data.sb->s_flags & SB_SYNCHRONOUS) 1315 fc->sb_flags |= SB_SYNCHRONOUS; 1316 1317 /* Get a superblock - note that we may end up sharing one that already exists */ 1318 fc->s_fs_info = server; 1319 s = sget_fc(fc, compare_super, nfs_set_super); 1320 fc->s_fs_info = NULL; 1321 if (IS_ERR(s)) { 1322 error = PTR_ERR(s); 1323 nfs_errorf(fc, "NFS: Couldn't get superblock"); 1324 goto out_err_nosb; 1325 } 1326 1327 if (s->s_fs_info != server) { 1328 nfs_free_server(server); 1329 server = NULL; 1330 } else { 1331 error = super_setup_bdi_name(s, "%u:%u", MAJOR(server->s_dev), 1332 MINOR(server->s_dev)); 1333 if (error) 1334 goto error_splat_super; 1335 s->s_bdi->io_pages = server->rpages; 1336 server->super = s; 1337 } 1338 1339 if (!s->s_root) { 1340 unsigned bsize = ctx->clone_data.inherited_bsize; 1341 /* initial superblock/root creation */ 1342 nfs_fill_super(s, ctx); 1343 if (bsize) { 1344 s->s_blocksize_bits = bsize; 1345 s->s_blocksize = 1U << bsize; 1346 } 1347 error = nfs_get_cache_cookie(s, ctx); 1348 if (error < 0) 1349 goto error_splat_super; 1350 } 1351 1352 error = nfs_get_root(s, fc); 1353 if (error < 0) { 1354 nfs_errorf(fc, "NFS: Couldn't get root dentry"); 1355 goto error_splat_super; 1356 } 1357 1358 s->s_flags |= SB_ACTIVE; 1359 error = 0; 1360 1361 out: 1362 return error; 1363 1364 out_err_nosb: 1365 nfs_free_server(server); 1366 goto out; 1367 error_splat_super: 1368 deactivate_locked_super(s); 1369 goto out; 1370 } 1371 1372 /* 1373 * Destroy an NFS superblock 1374 */ 1375 void nfs_kill_super(struct super_block *s) 1376 { 1377 struct nfs_server *server = NFS_SB(s); 1378 1379 nfs_sysfs_move_sb_to_server(server); 1380 kill_anon_super(s); 1381 1382 nfs_fscache_release_super_cookie(s); 1383 1384 nfs_free_server(server); 1385 } 1386 EXPORT_SYMBOL_GPL(nfs_kill_super); 1387 1388 #if IS_ENABLED(CONFIG_NFS_V4) 1389 1390 /* 1391 * NFS v4 module parameters need to stay in the 1392 * NFS client for backwards compatibility 1393 */ 1394 unsigned int nfs_callback_set_tcpport; 1395 unsigned short nfs_callback_nr_threads; 1396 /* Default cache timeout is 10 minutes */ 1397 unsigned int nfs_idmap_cache_timeout = 600; 1398 /* Turn off NFSv4 uid/gid mapping when using AUTH_SYS */ 1399 bool nfs4_disable_idmapping = true; 1400 unsigned short max_session_slots = NFS4_DEF_SLOT_TABLE_SIZE; 1401 unsigned short max_session_cb_slots = NFS4_DEF_CB_SLOT_TABLE_SIZE; 1402 unsigned short send_implementation_id = 1; 1403 char nfs4_client_id_uniquifier[NFS4_CLIENT_ID_UNIQ_LEN] = ""; 1404 bool recover_lost_locks = false; 1405 short nfs_delay_retrans = -1; 1406 1407 EXPORT_SYMBOL_GPL(nfs_callback_nr_threads); 1408 EXPORT_SYMBOL_GPL(nfs_callback_set_tcpport); 1409 EXPORT_SYMBOL_GPL(nfs_idmap_cache_timeout); 1410 EXPORT_SYMBOL_GPL(nfs4_disable_idmapping); 1411 EXPORT_SYMBOL_GPL(max_session_slots); 1412 EXPORT_SYMBOL_GPL(max_session_cb_slots); 1413 EXPORT_SYMBOL_GPL(send_implementation_id); 1414 EXPORT_SYMBOL_GPL(nfs4_client_id_uniquifier); 1415 EXPORT_SYMBOL_GPL(recover_lost_locks); 1416 EXPORT_SYMBOL_GPL(nfs_delay_retrans); 1417 1418 #define NFS_CALLBACK_MAXPORTNR (65535U) 1419 1420 static int param_set_portnr(const char *val, const struct kernel_param *kp) 1421 { 1422 unsigned long num; 1423 int ret; 1424 1425 if (!val) 1426 return -EINVAL; 1427 ret = kstrtoul(val, 0, &num); 1428 if (ret || num > NFS_CALLBACK_MAXPORTNR) 1429 return -EINVAL; 1430 *((unsigned int *)kp->arg) = num; 1431 return 0; 1432 } 1433 static const struct kernel_param_ops param_ops_portnr = { 1434 .set = param_set_portnr, 1435 .get = param_get_uint, 1436 }; 1437 #define param_check_portnr(name, p) __param_check(name, p, unsigned int) 1438 1439 module_param_named(callback_tcpport, nfs_callback_set_tcpport, portnr, 0644); 1440 module_param_named(callback_nr_threads, nfs_callback_nr_threads, ushort, 0644); 1441 MODULE_PARM_DESC(callback_nr_threads, "Number of threads that will be " 1442 "assigned to the NFSv4 callback channels."); 1443 module_param(nfs_idmap_cache_timeout, int, 0644); 1444 module_param(nfs4_disable_idmapping, bool, 0644); 1445 module_param_string(nfs4_unique_id, nfs4_client_id_uniquifier, 1446 NFS4_CLIENT_ID_UNIQ_LEN, 0600); 1447 MODULE_PARM_DESC(nfs4_disable_idmapping, 1448 "Turn off NFSv4 idmapping when using 'sec=sys'"); 1449 module_param(max_session_slots, ushort, 0644); 1450 MODULE_PARM_DESC(max_session_slots, "Maximum number of outstanding NFSv4.1 " 1451 "requests the client will negotiate"); 1452 module_param(max_session_cb_slots, ushort, 0644); 1453 MODULE_PARM_DESC(max_session_cb_slots, "Maximum number of parallel NFSv4.1 " 1454 "callbacks the client will process for a given server"); 1455 module_param(send_implementation_id, ushort, 0644); 1456 MODULE_PARM_DESC(send_implementation_id, 1457 "Send implementation ID with NFSv4.1 exchange_id"); 1458 MODULE_PARM_DESC(nfs4_unique_id, "nfs_client_id4 uniquifier string"); 1459 1460 module_param(recover_lost_locks, bool, 0644); 1461 MODULE_PARM_DESC(recover_lost_locks, 1462 "If the server reports that a lock might be lost, " 1463 "try to recover it risking data corruption."); 1464 1465 module_param_named(delay_retrans, nfs_delay_retrans, short, 0644); 1466 MODULE_PARM_DESC(delay_retrans, 1467 "Unless negative, specifies the number of times the NFSv4 " 1468 "client retries a request before returning an EAGAIN error, " 1469 "after a reply of NFS4ERR_DELAY from the server."); 1470 #endif /* CONFIG_NFS_V4 */ 1471