1/* 2 * linux/fs/nfs/super.c 3 * 4 * Copyright (C) 1992 Rick Sladkey 5 * 6 * nfs superblock handling functions 7 * 8 * Modularised by Alan Cox <Alan.Cox@linux.org>, while hacking some 9 * experimental NFS changes. Modularisation taken straight from SYS5 fs. 10 * 11 * Change to nfs_read_super() to permit NFS mounts to multi-homed hosts. 12 * J.S.Peatfield@damtp.cam.ac.uk 13 * 14 * Split from inode.c by David Howells <dhowells@redhat.com> 15 * 16 * - superblocks are indexed on server only - all inodes, dentries, etc. associated with a 17 * particular server are held in the same superblock 18 * - NFS superblocks can have several effective roots to the dentry tree 19 * - directory type roots are spliced into the tree when a path from one root reaches the root 20 * of another (see nfs_lookup()) 21 */ 22 23#include <linux/module.h> 24#include <linux/init.h> 25 26#include <linux/time.h> 27#include <linux/kernel.h> 28#include <linux/mm.h> 29#include <linux/string.h> 30#include <linux/stat.h> 31#include <linux/errno.h> 32#include <linux/unistd.h> 33#include <linux/sunrpc/clnt.h> 34#include <linux/sunrpc/stats.h> 35#include <linux/sunrpc/metrics.h> 36#include <linux/nfs_fs.h> 37#include <linux/nfs_mount.h> 38#include <linux/nfs4_mount.h> 39#include <linux/lockd/bind.h> 40#include <linux/smp_lock.h> 41#include <linux/seq_file.h> 42#include <linux/mount.h> 43#include <linux/nfs_idmap.h> 44#include <linux/vfs.h> 45#include <linux/inet.h> 46#include <linux/nfs_xdr.h> 47#include <linux/magic.h> 48 49#include <asm/system.h> 50#include <asm/uaccess.h> 51 52#include "nfs4_fs.h" 53#include "callback.h" 54#include "delegation.h" 55#include "iostat.h" 56#include "internal.h" 57 58#define NFSDBG_FACILITY NFSDBG_VFS 59 60static void nfs_umount_begin(struct vfsmount *, int); 61static int nfs_statfs(struct dentry *, struct kstatfs *); 62static int nfs_show_options(struct seq_file *, struct vfsmount *); 63static int nfs_show_stats(struct seq_file *, struct vfsmount *); 64static int nfs_get_sb(struct file_system_type *, int, const char *, void *, struct vfsmount *); 65static int nfs_xdev_get_sb(struct file_system_type *fs_type, 66 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt); 67static void nfs_kill_super(struct super_block *); 68 69static struct file_system_type nfs_fs_type = { 70 .owner = THIS_MODULE, 71 .name = "nfs", 72 .get_sb = nfs_get_sb, 73 .kill_sb = nfs_kill_super, 74 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA, 75}; 76 77struct file_system_type nfs_xdev_fs_type = { 78 .owner = THIS_MODULE, 79 .name = "nfs", 80 .get_sb = nfs_xdev_get_sb, 81 .kill_sb = nfs_kill_super, 82 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA, 83}; 84 85static const struct super_operations nfs_sops = { 86 .alloc_inode = nfs_alloc_inode, 87 .destroy_inode = nfs_destroy_inode, 88 .write_inode = nfs_write_inode, 89 .statfs = nfs_statfs, 90 .clear_inode = nfs_clear_inode, 91 .umount_begin = nfs_umount_begin, 92 .show_options = nfs_show_options, 93 .show_stats = nfs_show_stats, 94}; 95 96#ifdef CONFIG_NFS_V4 97static int nfs4_get_sb(struct file_system_type *fs_type, 98 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt); 99static int nfs4_xdev_get_sb(struct file_system_type *fs_type, 100 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt); 101static int nfs4_referral_get_sb(struct file_system_type *fs_type, 102 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt); 103static void nfs4_kill_super(struct super_block *sb); 104 105static struct file_system_type nfs4_fs_type = { 106 .owner = THIS_MODULE, 107 .name = "nfs4", 108 .get_sb = nfs4_get_sb, 109 .kill_sb = nfs4_kill_super, 110 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA, 111}; 112 113struct file_system_type nfs4_xdev_fs_type = { 114 .owner = THIS_MODULE, 115 .name = "nfs4", 116 .get_sb = nfs4_xdev_get_sb, 117 .kill_sb = nfs4_kill_super, 118 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA, 119}; 120 121struct file_system_type nfs4_referral_fs_type = { 122 .owner = THIS_MODULE, 123 .name = "nfs4", 124 .get_sb = nfs4_referral_get_sb, 125 .kill_sb = nfs4_kill_super, 126 .fs_flags = FS_RENAME_DOES_D_MOVE|FS_REVAL_DOT|FS_BINARY_MOUNTDATA, 127}; 128 129static const struct super_operations nfs4_sops = { 130 .alloc_inode = nfs_alloc_inode, 131 .destroy_inode = nfs_destroy_inode, 132 .write_inode = nfs_write_inode, 133 .statfs = nfs_statfs, 134 .clear_inode = nfs4_clear_inode, 135 .umount_begin = nfs_umount_begin, 136 .show_options = nfs_show_options, 137 .show_stats = nfs_show_stats, 138}; 139#endif 140 141static struct shrinker *acl_shrinker; 142 143/* 144 * Register the NFS filesystems 145 */ 146int __init register_nfs_fs(void) 147{ 148 int ret; 149 150 ret = register_filesystem(&nfs_fs_type); 151 if (ret < 0) 152 goto error_0; 153 154 ret = nfs_register_sysctl(); 155 if (ret < 0) 156 goto error_1; 157#ifdef CONFIG_NFS_V4 158 ret = register_filesystem(&nfs4_fs_type); 159 if (ret < 0) 160 goto error_2; 161#endif 162 acl_shrinker = set_shrinker(DEFAULT_SEEKS, nfs_access_cache_shrinker); 163 return 0; 164 165#ifdef CONFIG_NFS_V4 166error_2: 167 nfs_unregister_sysctl(); 168#endif 169error_1: 170 unregister_filesystem(&nfs_fs_type); 171error_0: 172 return ret; 173} 174 175/* 176 * Unregister the NFS filesystems 177 */ 178void __exit unregister_nfs_fs(void) 179{ 180 if (acl_shrinker != NULL) 181 remove_shrinker(acl_shrinker); 182#ifdef CONFIG_NFS_V4 183 unregister_filesystem(&nfs4_fs_type); 184 nfs_unregister_sysctl(); 185#endif 186 unregister_filesystem(&nfs_fs_type); 187} 188 189/* 190 * Deliver file system statistics to userspace 191 */ 192static int nfs_statfs(struct dentry *dentry, struct kstatfs *buf) 193{ 194 struct nfs_server *server = NFS_SB(dentry->d_sb); 195 unsigned char blockbits; 196 unsigned long blockres; 197 struct nfs_fh *fh = NFS_FH(dentry->d_inode); 198 struct nfs_fattr fattr; 199 struct nfs_fsstat res = { 200 .fattr = &fattr, 201 }; 202 int error; 203 204 lock_kernel(); 205 206 error = server->nfs_client->rpc_ops->statfs(server, fh, &res); 207 if (error < 0) 208 goto out_err; 209 buf->f_type = NFS_SUPER_MAGIC; 210 211 /* 212 * Current versions of glibc do not correctly handle the 213 * case where f_frsize != f_bsize. Eventually we want to 214 * report the value of wtmult in this field. 215 */ 216 buf->f_frsize = dentry->d_sb->s_blocksize; 217 218 /* 219 * On most *nix systems, f_blocks, f_bfree, and f_bavail 220 * are reported in units of f_frsize. Linux hasn't had 221 * an f_frsize field in its statfs struct until recently, 222 * thus historically Linux's sys_statfs reports these 223 * fields in units of f_bsize. 224 */ 225 buf->f_bsize = dentry->d_sb->s_blocksize; 226 blockbits = dentry->d_sb->s_blocksize_bits; 227 blockres = (1 << blockbits) - 1; 228 buf->f_blocks = (res.tbytes + blockres) >> blockbits; 229 buf->f_bfree = (res.fbytes + blockres) >> blockbits; 230 buf->f_bavail = (res.abytes + blockres) >> blockbits; 231 232 buf->f_files = res.tfiles; 233 buf->f_ffree = res.afiles; 234 235 buf->f_namelen = server->namelen; 236 237 unlock_kernel(); 238 return 0; 239 240 out_err: 241 dprintk("%s: statfs error = %d\n", __FUNCTION__, -error); 242 unlock_kernel(); 243 return error; 244} 245 246/* 247 * Map the security flavour number to a name 248 */ 249static const char *nfs_pseudoflavour_to_name(rpc_authflavor_t flavour) 250{ 251 static const struct { 252 rpc_authflavor_t flavour; 253 const char *str; 254 } sec_flavours[] = { 255 { RPC_AUTH_NULL, "null" }, 256 { RPC_AUTH_UNIX, "sys" }, 257 { RPC_AUTH_GSS_KRB5, "krb5" }, 258 { RPC_AUTH_GSS_KRB5I, "krb5i" }, 259 { RPC_AUTH_GSS_KRB5P, "krb5p" }, 260 { RPC_AUTH_GSS_LKEY, "lkey" }, 261 { RPC_AUTH_GSS_LKEYI, "lkeyi" }, 262 { RPC_AUTH_GSS_LKEYP, "lkeyp" }, 263 { RPC_AUTH_GSS_SPKM, "spkm" }, 264 { RPC_AUTH_GSS_SPKMI, "spkmi" }, 265 { RPC_AUTH_GSS_SPKMP, "spkmp" }, 266 { -1, "unknown" } 267 }; 268 int i; 269 270 for (i=0; sec_flavours[i].flavour != -1; i++) { 271 if (sec_flavours[i].flavour == flavour) 272 break; 273 } 274 return sec_flavours[i].str; 275} 276 277/* 278 * Describe the mount options in force on this server representation 279 */ 280static void nfs_show_mount_options(struct seq_file *m, struct nfs_server *nfss, int showdefaults) 281{ 282 static const struct proc_nfs_info { 283 int flag; 284 const char *str; 285 const char *nostr; 286 } nfs_info[] = { 287 { NFS_MOUNT_SOFT, ",soft", ",hard" }, 288 { NFS_MOUNT_INTR, ",intr", "" }, 289 { NFS_MOUNT_NOCTO, ",nocto", "" }, 290 { NFS_MOUNT_NOAC, ",noac", "" }, 291 { NFS_MOUNT_NONLM, ",nolock", "" }, 292 { NFS_MOUNT_NOACL, ",noacl", "" }, 293 { NFS_MOUNT_NORDIRPLUS, ",nordirplus", "" }, 294 { 0, NULL, NULL } 295 }; 296 const struct proc_nfs_info *nfs_infop; 297 struct nfs_client *clp = nfss->nfs_client; 298 char buf[12]; 299 const char *proto; 300 301 seq_printf(m, ",vers=%d", clp->rpc_ops->version); 302 seq_printf(m, ",rsize=%d", nfss->rsize); 303 seq_printf(m, ",wsize=%d", nfss->wsize); 304 if (nfss->acregmin != 3*HZ || showdefaults) 305 seq_printf(m, ",acregmin=%d", nfss->acregmin/HZ); 306 if (nfss->acregmax != 60*HZ || showdefaults) 307 seq_printf(m, ",acregmax=%d", nfss->acregmax/HZ); 308 if (nfss->acdirmin != 30*HZ || showdefaults) 309 seq_printf(m, ",acdirmin=%d", nfss->acdirmin/HZ); 310 if (nfss->acdirmax != 60*HZ || showdefaults) 311 seq_printf(m, ",acdirmax=%d", nfss->acdirmax/HZ); 312 for (nfs_infop = nfs_info; nfs_infop->flag; nfs_infop++) { 313 if (nfss->flags & nfs_infop->flag) 314 seq_puts(m, nfs_infop->str); 315 else 316 seq_puts(m, nfs_infop->nostr); 317 } 318 switch (nfss->client->cl_xprt->prot) { 319 case IPPROTO_TCP: 320 proto = "tcp"; 321 break; 322 case IPPROTO_UDP: 323 proto = "udp"; 324 break; 325 default: 326 snprintf(buf, sizeof(buf), "%u", nfss->client->cl_xprt->prot); 327 proto = buf; 328 } 329 seq_printf(m, ",proto=%s", proto); 330 seq_printf(m, ",timeo=%lu", 10U * clp->retrans_timeo / HZ); 331 seq_printf(m, ",retrans=%u", clp->retrans_count); 332 seq_printf(m, ",sec=%s", nfs_pseudoflavour_to_name(nfss->client->cl_auth->au_flavor)); 333} 334 335/* 336 * Describe the mount options on this VFS mountpoint 337 */ 338static int nfs_show_options(struct seq_file *m, struct vfsmount *mnt) 339{ 340 struct nfs_server *nfss = NFS_SB(mnt->mnt_sb); 341 342 nfs_show_mount_options(m, nfss, 0); 343 344 seq_puts(m, ",addr="); 345 seq_escape(m, nfss->nfs_client->cl_hostname, " \t\n\\"); 346 347 return 0; 348} 349 350/* 351 * Present statistical information for this VFS mountpoint 352 */ 353static int nfs_show_stats(struct seq_file *m, struct vfsmount *mnt) 354{ 355 int i, cpu; 356 struct nfs_server *nfss = NFS_SB(mnt->mnt_sb); 357 struct rpc_auth *auth = nfss->client->cl_auth; 358 struct nfs_iostats totals = { }; 359 360 seq_printf(m, "statvers=%s", NFS_IOSTAT_VERS); 361 362 /* 363 * Display all mount option settings 364 */ 365 seq_printf(m, "\n\topts:\t"); 366 seq_puts(m, mnt->mnt_sb->s_flags & MS_RDONLY ? "ro" : "rw"); 367 seq_puts(m, mnt->mnt_sb->s_flags & MS_SYNCHRONOUS ? ",sync" : ""); 368 seq_puts(m, mnt->mnt_sb->s_flags & MS_NOATIME ? ",noatime" : ""); 369 seq_puts(m, mnt->mnt_sb->s_flags & MS_NODIRATIME ? ",nodiratime" : ""); 370 nfs_show_mount_options(m, nfss, 1); 371 372 seq_printf(m, "\n\tage:\t%lu", (jiffies - nfss->mount_time) / HZ); 373 374 seq_printf(m, "\n\tcaps:\t"); 375 seq_printf(m, "caps=0x%x", nfss->caps); 376 seq_printf(m, ",wtmult=%d", nfss->wtmult); 377 seq_printf(m, ",dtsize=%d", nfss->dtsize); 378 seq_printf(m, ",bsize=%d", nfss->bsize); 379 seq_printf(m, ",namelen=%d", nfss->namelen); 380 381#ifdef CONFIG_NFS_V4 382 if (nfss->nfs_client->cl_nfsversion == 4) { 383 seq_printf(m, "\n\tnfsv4:\t"); 384 seq_printf(m, "bm0=0x%x", nfss->attr_bitmask[0]); 385 seq_printf(m, ",bm1=0x%x", nfss->attr_bitmask[1]); 386 seq_printf(m, ",acl=0x%x", nfss->acl_bitmask); 387 } 388#endif 389 390 /* 391 * Display security flavor in effect for this mount 392 */ 393 seq_printf(m, "\n\tsec:\tflavor=%d", auth->au_ops->au_flavor); 394 if (auth->au_flavor) 395 seq_printf(m, ",pseudoflavor=%d", auth->au_flavor); 396 397 /* 398 * Display superblock I/O counters 399 */ 400 for_each_possible_cpu(cpu) { 401 struct nfs_iostats *stats; 402 403 preempt_disable(); 404 stats = per_cpu_ptr(nfss->io_stats, cpu); 405 406 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 407 totals.events[i] += stats->events[i]; 408 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 409 totals.bytes[i] += stats->bytes[i]; 410 411 preempt_enable(); 412 } 413 414 seq_printf(m, "\n\tevents:\t"); 415 for (i = 0; i < __NFSIOS_COUNTSMAX; i++) 416 seq_printf(m, "%lu ", totals.events[i]); 417 seq_printf(m, "\n\tbytes:\t"); 418 for (i = 0; i < __NFSIOS_BYTESMAX; i++) 419 seq_printf(m, "%Lu ", totals.bytes[i]); 420 seq_printf(m, "\n"); 421 422 rpc_print_iostats(m, nfss->client); 423 424 return 0; 425} 426 427/* 428 * Begin unmount by attempting to remove all automounted mountpoints we added 429 * in response to xdev traversals and referrals 430 */ 431static void nfs_umount_begin(struct vfsmount *vfsmnt, int flags) 432{ 433 shrink_submounts(vfsmnt, &nfs_automount_list); 434} 435 436/* 437 * Validate the NFS2/NFS3 mount data 438 * - fills in the mount root filehandle 439 */ 440static int nfs_validate_mount_data(struct nfs_mount_data *data, 441 struct nfs_fh *mntfh) 442{ 443 if (data == NULL) { 444 dprintk("%s: missing data argument\n", __FUNCTION__); 445 return -EINVAL; 446 } 447 448 if (data->version <= 0 || data->version > NFS_MOUNT_VERSION) { 449 dprintk("%s: bad mount version\n", __FUNCTION__); 450 return -EINVAL; 451 } 452 453 switch (data->version) { 454 case 1: 455 data->namlen = 0; 456 case 2: 457 data->bsize = 0; 458 case 3: 459 if (data->flags & NFS_MOUNT_VER3) { 460 dprintk("%s: mount structure version %d does not support NFSv3\n", 461 __FUNCTION__, 462 data->version); 463 return -EINVAL; 464 } 465 data->root.size = NFS2_FHSIZE; 466 memcpy(data->root.data, data->old_root.data, NFS2_FHSIZE); 467 case 4: 468 if (data->flags & NFS_MOUNT_SECFLAVOUR) { 469 dprintk("%s: mount structure version %d does not support strong security\n", 470 __FUNCTION__, 471 data->version); 472 return -EINVAL; 473 } 474 case 5: 475 memset(data->context, 0, sizeof(data->context)); 476 } 477 478 /* Set the pseudoflavor */ 479 if (!(data->flags & NFS_MOUNT_SECFLAVOUR)) 480 data->pseudoflavor = RPC_AUTH_UNIX; 481 482#ifndef CONFIG_NFS_V3 483 /* If NFSv3 is not compiled in, return -EPROTONOSUPPORT */ 484 if (data->flags & NFS_MOUNT_VER3) { 485 dprintk("%s: NFSv3 not compiled into kernel\n", __FUNCTION__); 486 return -EPROTONOSUPPORT; 487 } 488#endif /* CONFIG_NFS_V3 */ 489 490 /* We now require that the mount process passes the remote address */ 491 if (data->addr.sin_addr.s_addr == INADDR_ANY) { 492 dprintk("%s: mount program didn't pass remote address!\n", 493 __FUNCTION__); 494 return -EINVAL; 495 } 496 497 /* Prepare the root filehandle */ 498 if (data->flags & NFS_MOUNT_VER3) 499 mntfh->size = data->root.size; 500 else 501 mntfh->size = NFS2_FHSIZE; 502 503 if (mntfh->size > sizeof(mntfh->data)) { 504 dprintk("%s: invalid root filehandle\n", __FUNCTION__); 505 return -EINVAL; 506 } 507 508 memcpy(mntfh->data, data->root.data, mntfh->size); 509 if (mntfh->size < sizeof(mntfh->data)) 510 memset(mntfh->data + mntfh->size, 0, 511 sizeof(mntfh->data) - mntfh->size); 512 513 return 0; 514} 515 516/* 517 * Initialise the common bits of the superblock 518 */ 519static inline void nfs_initialise_sb(struct super_block *sb) 520{ 521 struct nfs_server *server = NFS_SB(sb); 522 523 sb->s_magic = NFS_SUPER_MAGIC; 524 525 /* We probably want something more informative here */ 526 snprintf(sb->s_id, sizeof(sb->s_id), 527 "%x:%x", MAJOR(sb->s_dev), MINOR(sb->s_dev)); 528 529 if (sb->s_blocksize == 0) 530 sb->s_blocksize = nfs_block_bits(server->wsize, 531 &sb->s_blocksize_bits); 532 533 if (server->flags & NFS_MOUNT_NOAC) 534 sb->s_flags |= MS_SYNCHRONOUS; 535 536 nfs_super_set_maxbytes(sb, server->maxfilesize); 537} 538 539/* 540 * Finish setting up an NFS2/3 superblock 541 */ 542static void nfs_fill_super(struct super_block *sb, struct nfs_mount_data *data) 543{ 544 struct nfs_server *server = NFS_SB(sb); 545 546 sb->s_blocksize_bits = 0; 547 sb->s_blocksize = 0; 548 if (data->bsize) 549 sb->s_blocksize = nfs_block_size(data->bsize, &sb->s_blocksize_bits); 550 551 if (server->flags & NFS_MOUNT_VER3) { 552 /* The VFS shouldn't apply the umask to mode bits. We will do 553 * so ourselves when necessary. 554 */ 555 sb->s_flags |= MS_POSIXACL; 556 sb->s_time_gran = 1; 557 } 558 559 sb->s_op = &nfs_sops; 560 nfs_initialise_sb(sb); 561} 562 563/* 564 * Finish setting up a cloned NFS2/3 superblock 565 */ 566static void nfs_clone_super(struct super_block *sb, 567 const struct super_block *old_sb) 568{ 569 struct nfs_server *server = NFS_SB(sb); 570 571 sb->s_blocksize_bits = old_sb->s_blocksize_bits; 572 sb->s_blocksize = old_sb->s_blocksize; 573 sb->s_maxbytes = old_sb->s_maxbytes; 574 575 if (server->flags & NFS_MOUNT_VER3) { 576 /* The VFS shouldn't apply the umask to mode bits. We will do 577 * so ourselves when necessary. 578 */ 579 sb->s_flags |= MS_POSIXACL; 580 sb->s_time_gran = 1; 581 } 582 583 sb->s_op = old_sb->s_op; 584 nfs_initialise_sb(sb); 585} 586 587static int nfs_set_super(struct super_block *s, void *_server) 588{ 589 struct nfs_server *server = _server; 590 int ret; 591 592 s->s_fs_info = server; 593 ret = set_anon_super(s, server); 594 if (ret == 0) 595 server->s_dev = s->s_dev; 596 return ret; 597} 598 599static int nfs_compare_super(struct super_block *sb, void *data) 600{ 601 struct nfs_server *server = data, *old = NFS_SB(sb); 602 603 if (old->nfs_client != server->nfs_client) 604 return 0; 605 if (memcmp(&old->fsid, &server->fsid, sizeof(old->fsid)) != 0) 606 return 0; 607 return 1; 608} 609 610static int nfs_get_sb(struct file_system_type *fs_type, 611 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt) 612{ 613 struct nfs_server *server = NULL; 614 struct super_block *s; 615 struct nfs_fh mntfh; 616 struct nfs_mount_data *data = raw_data; 617 struct dentry *mntroot; 618 int error; 619 620 /* Validate the mount data */ 621 error = nfs_validate_mount_data(data, &mntfh); 622 if (error < 0) 623 return error; 624 625 /* Get a volume representation */ 626 server = nfs_create_server(data, &mntfh); 627 if (IS_ERR(server)) { 628 error = PTR_ERR(server); 629 goto out_err_noserver; 630 } 631 632 /* Get a superblock - note that we may end up sharing one that already exists */ 633 s = sget(fs_type, nfs_compare_super, nfs_set_super, server); 634 if (IS_ERR(s)) { 635 error = PTR_ERR(s); 636 goto out_err_nosb; 637 } 638 639 if (s->s_fs_info != server) { 640 nfs_free_server(server); 641 server = NULL; 642 } 643 644 if (!s->s_root) { 645 /* initial superblock/root creation */ 646 s->s_flags = flags; 647 nfs_fill_super(s, data); 648 } 649 650 mntroot = nfs_get_root(s, &mntfh); 651 if (IS_ERR(mntroot)) { 652 error = PTR_ERR(mntroot); 653 goto error_splat_super; 654 } 655 656 s->s_flags |= MS_ACTIVE; 657 mnt->mnt_sb = s; 658 mnt->mnt_root = mntroot; 659 return 0; 660 661out_err_nosb: 662 nfs_free_server(server); 663out_err_noserver: 664 return error; 665 666error_splat_super: 667 up_write(&s->s_umount); 668 deactivate_super(s); 669 return error; 670} 671 672/* 673 * Destroy an NFS2/3 superblock 674 */ 675static void nfs_kill_super(struct super_block *s) 676{ 677 struct nfs_server *server = NFS_SB(s); 678 679 kill_anon_super(s); 680 nfs_free_server(server); 681} 682 683/* 684 * Clone an NFS2/3 server record on xdev traversal (FSID-change) 685 */ 686static int nfs_xdev_get_sb(struct file_system_type *fs_type, int flags, 687 const char *dev_name, void *raw_data, 688 struct vfsmount *mnt) 689{ 690 struct nfs_clone_mount *data = raw_data; 691 struct super_block *s; 692 struct nfs_server *server; 693 struct dentry *mntroot; 694 int error; 695 696 dprintk("--> nfs_xdev_get_sb()\n"); 697 698 /* create a new volume representation */ 699 server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr); 700 if (IS_ERR(server)) { 701 error = PTR_ERR(server); 702 goto out_err_noserver; 703 } 704 705 /* Get a superblock - note that we may end up sharing one that already exists */ 706 s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server); 707 if (IS_ERR(s)) { 708 error = PTR_ERR(s); 709 goto out_err_nosb; 710 } 711 712 if (s->s_fs_info != server) { 713 nfs_free_server(server); 714 server = NULL; 715 } 716 717 if (!s->s_root) { 718 /* initial superblock/root creation */ 719 s->s_flags = flags; 720 nfs_clone_super(s, data->sb); 721 } 722 723 mntroot = nfs_get_root(s, data->fh); 724 if (IS_ERR(mntroot)) { 725 error = PTR_ERR(mntroot); 726 goto error_splat_super; 727 } 728 729 s->s_flags |= MS_ACTIVE; 730 mnt->mnt_sb = s; 731 mnt->mnt_root = mntroot; 732 733 dprintk("<-- nfs_xdev_get_sb() = 0\n"); 734 return 0; 735 736out_err_nosb: 737 nfs_free_server(server); 738out_err_noserver: 739 dprintk("<-- nfs_xdev_get_sb() = %d [error]\n", error); 740 return error; 741 742error_splat_super: 743 up_write(&s->s_umount); 744 deactivate_super(s); 745 dprintk("<-- nfs_xdev_get_sb() = %d [splat]\n", error); 746 return error; 747} 748 749#ifdef CONFIG_NFS_V4 750 751/* 752 * Finish setting up a cloned NFS4 superblock 753 */ 754static void nfs4_clone_super(struct super_block *sb, 755 const struct super_block *old_sb) 756{ 757 sb->s_blocksize_bits = old_sb->s_blocksize_bits; 758 sb->s_blocksize = old_sb->s_blocksize; 759 sb->s_maxbytes = old_sb->s_maxbytes; 760 sb->s_time_gran = 1; 761 sb->s_op = old_sb->s_op; 762 nfs_initialise_sb(sb); 763} 764 765/* 766 * Set up an NFS4 superblock 767 */ 768static void nfs4_fill_super(struct super_block *sb) 769{ 770 sb->s_time_gran = 1; 771 sb->s_op = &nfs4_sops; 772 nfs_initialise_sb(sb); 773} 774 775static void *nfs_copy_user_string(char *dst, struct nfs_string *src, int maxlen) 776{ 777 void *p = NULL; 778 779 if (!src->len) 780 return ERR_PTR(-EINVAL); 781 if (src->len < maxlen) 782 maxlen = src->len; 783 if (dst == NULL) { 784 p = dst = kmalloc(maxlen + 1, GFP_KERNEL); 785 if (p == NULL) 786 return ERR_PTR(-ENOMEM); 787 } 788 if (copy_from_user(dst, src->data, maxlen)) { 789 kfree(p); 790 return ERR_PTR(-EFAULT); 791 } 792 dst[maxlen] = '\0'; 793 return dst; 794} 795 796/* 797 * Get the superblock for an NFS4 mountpoint 798 */ 799static int nfs4_get_sb(struct file_system_type *fs_type, 800 int flags, const char *dev_name, void *raw_data, struct vfsmount *mnt) 801{ 802 struct nfs4_mount_data *data = raw_data; 803 struct super_block *s; 804 struct nfs_server *server; 805 struct sockaddr_in addr; 806 rpc_authflavor_t authflavour; 807 struct nfs_fh mntfh; 808 struct dentry *mntroot; 809 char *mntpath = NULL, *hostname = NULL, ip_addr[16]; 810 void *p; 811 int error; 812 813 if (data == NULL) { 814 dprintk("%s: missing data argument\n", __FUNCTION__); 815 return -EINVAL; 816 } 817 if (data->version <= 0 || data->version > NFS4_MOUNT_VERSION) { 818 dprintk("%s: bad mount version\n", __FUNCTION__); 819 return -EINVAL; 820 } 821 822 /* We now require that the mount process passes the remote address */ 823 if (data->host_addrlen != sizeof(addr)) 824 return -EINVAL; 825 826 if (copy_from_user(&addr, data->host_addr, sizeof(addr))) 827 return -EFAULT; 828 829 if (addr.sin_family != AF_INET || 830 addr.sin_addr.s_addr == INADDR_ANY 831 ) { 832 dprintk("%s: mount program didn't pass remote IP address!\n", 833 __FUNCTION__); 834 return -EINVAL; 835 } 836 /* RFC3530: The default port for NFS is 2049 */ 837 if (addr.sin_port == 0) 838 addr.sin_port = htons(NFS_PORT); 839 840 /* Grab the authentication type */ 841 authflavour = RPC_AUTH_UNIX; 842 if (data->auth_flavourlen != 0) { 843 if (data->auth_flavourlen != 1) { 844 dprintk("%s: Invalid number of RPC auth flavours %d.\n", 845 __FUNCTION__, data->auth_flavourlen); 846 error = -EINVAL; 847 goto out_err_noserver; 848 } 849 850 if (copy_from_user(&authflavour, data->auth_flavours, 851 sizeof(authflavour))) { 852 error = -EFAULT; 853 goto out_err_noserver; 854 } 855 } 856 857 p = nfs_copy_user_string(NULL, &data->hostname, 256); 858 if (IS_ERR(p)) 859 goto out_err; 860 hostname = p; 861 862 p = nfs_copy_user_string(NULL, &data->mnt_path, 1024); 863 if (IS_ERR(p)) 864 goto out_err; 865 mntpath = p; 866 867 dprintk("MNTPATH: %s\n", mntpath); 868 869 p = nfs_copy_user_string(ip_addr, &data->client_addr, 870 sizeof(ip_addr) - 1); 871 if (IS_ERR(p)) 872 goto out_err; 873 874 /* Get a volume representation */ 875 server = nfs4_create_server(data, hostname, &addr, mntpath, ip_addr, 876 authflavour, &mntfh); 877 if (IS_ERR(server)) { 878 error = PTR_ERR(server); 879 goto out_err_noserver; 880 } 881 882 /* Get a superblock - note that we may end up sharing one that already exists */ 883 s = sget(fs_type, nfs_compare_super, nfs_set_super, server); 884 if (IS_ERR(s)) { 885 error = PTR_ERR(s); 886 goto out_free; 887 } 888 889 if (s->s_fs_info != server) { 890 nfs_free_server(server); 891 server = NULL; 892 } 893 894 if (!s->s_root) { 895 /* initial superblock/root creation */ 896 s->s_flags = flags; 897 nfs4_fill_super(s); 898 } 899 900 mntroot = nfs4_get_root(s, &mntfh); 901 if (IS_ERR(mntroot)) { 902 error = PTR_ERR(mntroot); 903 goto error_splat_super; 904 } 905 906 s->s_flags |= MS_ACTIVE; 907 mnt->mnt_sb = s; 908 mnt->mnt_root = mntroot; 909 kfree(mntpath); 910 kfree(hostname); 911 return 0; 912 913out_err: 914 error = PTR_ERR(p); 915 goto out_err_noserver; 916 917out_free: 918 nfs_free_server(server); 919out_err_noserver: 920 kfree(mntpath); 921 kfree(hostname); 922 return error; 923 924error_splat_super: 925 up_write(&s->s_umount); 926 deactivate_super(s); 927 goto out_err_noserver; 928} 929 930static void nfs4_kill_super(struct super_block *sb) 931{ 932 struct nfs_server *server = NFS_SB(sb); 933 934 nfs_return_all_delegations(sb); 935 kill_anon_super(sb); 936 937 nfs4_renewd_prepare_shutdown(server); 938 nfs_free_server(server); 939} 940 941/* 942 * Clone an NFS4 server record on xdev traversal (FSID-change) 943 */ 944static int nfs4_xdev_get_sb(struct file_system_type *fs_type, int flags, 945 const char *dev_name, void *raw_data, 946 struct vfsmount *mnt) 947{ 948 struct nfs_clone_mount *data = raw_data; 949 struct super_block *s; 950 struct nfs_server *server; 951 struct dentry *mntroot; 952 int error; 953 954 dprintk("--> nfs4_xdev_get_sb()\n"); 955 956 /* create a new volume representation */ 957 server = nfs_clone_server(NFS_SB(data->sb), data->fh, data->fattr); 958 if (IS_ERR(server)) { 959 error = PTR_ERR(server); 960 goto out_err_noserver; 961 } 962 963 /* Get a superblock - note that we may end up sharing one that already exists */ 964 s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server); 965 if (IS_ERR(s)) { 966 error = PTR_ERR(s); 967 goto out_err_nosb; 968 } 969 970 if (s->s_fs_info != server) { 971 nfs_free_server(server); 972 server = NULL; 973 } 974 975 if (!s->s_root) { 976 /* initial superblock/root creation */ 977 s->s_flags = flags; 978 nfs4_clone_super(s, data->sb); 979 } 980 981 mntroot = nfs4_get_root(s, data->fh); 982 if (IS_ERR(mntroot)) { 983 error = PTR_ERR(mntroot); 984 goto error_splat_super; 985 } 986 987 s->s_flags |= MS_ACTIVE; 988 mnt->mnt_sb = s; 989 mnt->mnt_root = mntroot; 990 991 dprintk("<-- nfs4_xdev_get_sb() = 0\n"); 992 return 0; 993 994out_err_nosb: 995 nfs_free_server(server); 996out_err_noserver: 997 dprintk("<-- nfs4_xdev_get_sb() = %d [error]\n", error); 998 return error; 999 1000error_splat_super: 1001 up_write(&s->s_umount); 1002 deactivate_super(s); 1003 dprintk("<-- nfs4_xdev_get_sb() = %d [splat]\n", error); 1004 return error; 1005} 1006 1007/* 1008 * Create an NFS4 server record on referral traversal 1009 */ 1010static int nfs4_referral_get_sb(struct file_system_type *fs_type, int flags, 1011 const char *dev_name, void *raw_data, 1012 struct vfsmount *mnt) 1013{ 1014 struct nfs_clone_mount *data = raw_data; 1015 struct super_block *s; 1016 struct nfs_server *server; 1017 struct dentry *mntroot; 1018 struct nfs_fh mntfh; 1019 int error; 1020 1021 dprintk("--> nfs4_referral_get_sb()\n"); 1022 1023 /* create a new volume representation */ 1024 server = nfs4_create_referral_server(data, &mntfh); 1025 if (IS_ERR(server)) { 1026 error = PTR_ERR(server); 1027 goto out_err_noserver; 1028 } 1029 1030 /* Get a superblock - note that we may end up sharing one that already exists */ 1031 s = sget(&nfs_fs_type, nfs_compare_super, nfs_set_super, server); 1032 if (IS_ERR(s)) { 1033 error = PTR_ERR(s); 1034 goto out_err_nosb; 1035 } 1036 1037 if (s->s_fs_info != server) { 1038 nfs_free_server(server); 1039 server = NULL; 1040 } 1041 1042 if (!s->s_root) { 1043 /* initial superblock/root creation */ 1044 s->s_flags = flags; 1045 nfs4_fill_super(s); 1046 } 1047 1048 mntroot = nfs4_get_root(s, &mntfh); 1049 if (IS_ERR(mntroot)) { 1050 error = PTR_ERR(mntroot); 1051 goto error_splat_super; 1052 } 1053 1054 s->s_flags |= MS_ACTIVE; 1055 mnt->mnt_sb = s; 1056 mnt->mnt_root = mntroot; 1057 1058 dprintk("<-- nfs4_referral_get_sb() = 0\n"); 1059 return 0; 1060 1061out_err_nosb: 1062 nfs_free_server(server); 1063out_err_noserver: 1064 dprintk("<-- nfs4_referral_get_sb() = %d [error]\n", error); 1065 return error; 1066 1067error_splat_super: 1068 up_write(&s->s_umount); 1069 deactivate_super(s); 1070 dprintk("<-- nfs4_referral_get_sb() = %d [splat]\n", error); 1071 return error; 1072} 1073 1074#endif /* CONFIG_NFS_V4 */ 1075