fs/nfs/proc.c

   1 /*
   2  *  linux/fs/nfs/proc.c
   3  *
   4  *  Copyright (C) 1992, 1993, 1994  Rick Sladkey
   5  *
   6  *  OS-independent nfs remote procedure call functions
   7  *
   8  *  Tuned by Alan Cox <A.Cox@swansea.ac.uk> for >3K buffers
   9  *  so at last we can have decent(ish) throughput off a
  10  *  Sun server.
  11  *
  12  *  Coding optimized and cleaned up by Florian La Roche.
  13  *  Note: Error returns are optimized for NFS_OK, which isn't translated via
  14  *  nfs_stat_to_errno(), but happens to be already the right return code.
  15  *
  16  *  Also, the code currently doesn't check the size of the packet, when
  17  *  it decodes the packet.
  18  *
  19  *  Feel free to fix it and mail me the diffs if it worries you.
  20  *
  21  *  Completely rewritten to support the new RPC call interface;
  22  *  rewrote and moved the entire XDR stuff to xdr.c
  23  *  --Olaf Kirch June 1996
  24  *
  25  *  The code below initializes all auto variables explicitly, otherwise
  26  *  it will fail to work as a module (gcc generates a memset call for an
  27  *  incomplete struct).
  28  */
  29
  30 #include <linux/types.h>
  31 #include <linux/param.h>
  32 #include <linux/time.h>
  33 #include <linux/mm.h>
  34 #include <linux/errno.h>
  35 #include <linux/string.h>
  36 #include <linux/in.h>
  37 #include <linux/pagemap.h>
  38 #include <linux/sunrpc/clnt.h>
  39 #include <linux/nfs.h>
  40 #include <linux/nfs2.h>
  41 #include <linux/nfs_fs.h>
  42 #include <linux/nfs_page.h>
  43 #include <linux/lockd/bind.h>
  44 #include "internal.h"
  45
  46 #define NFSDBG_FACILITY         NFSDBG_PROC
  47
  48 /*
  49  * wrapper to handle the -EKEYEXPIRED error message. This should generally
  50  * only happen if using krb5 auth and a user's TGT expires. NFSv2 doesn't
  51  * support the NFSERR_JUKEBOX error code, but we handle this situation in the
  52  * same way that we handle that error with NFSv3.
  53  */
  54 static int
  55 nfs_rpc_wrapper(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
  56 {
  57         int res;
  58         do {
  59                 res = rpc_call_sync(clnt, msg, flags);
  60                 if (res != -EKEYEXPIRED)
  61                         break;
  62                 schedule_timeout_killable(NFS_JUKEBOX_RETRY_TIME);
  63                 res = -ERESTARTSYS;
  64         } while (!fatal_signal_pending(current));
  65         return res;
  66 }
  67
  68 #define rpc_call_sync(clnt, msg, flags) nfs_rpc_wrapper(clnt, msg, flags)
  69
  70 static int
  71 nfs_async_handle_expired_key(struct rpc_task *task)
  72 {
  73         if (task->tk_status != -EKEYEXPIRED)
  74                 return 0;
  75         task->tk_status = 0;
  76         rpc_restart_call(task);
  77         rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
  78         return 1;
  79 }
  80
  81 /*
  82  * Bare-bones access to getattr: this is for nfs_read_super.
  83  */
  84 static int
  85 nfs_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
  86                   struct nfs_fsinfo *info)
  87 {
  88         struct nfs_fattr *fattr = info->fattr;
  89         struct nfs2_fsstat fsinfo;
  90         struct rpc_message msg = {
  91                 .rpc_proc       = &nfs_procedures[NFSPROC_GETATTR],
  92                 .rpc_argp       = fhandle,
  93                 .rpc_resp       = fattr,
  94         };
  95         int status;
  96
  97         dprintk("%s: call getattr\n", __func__);
  98         nfs_fattr_init(fattr);
  99         status = rpc_call_sync(server->client, &msg, 0);
 100         /* Retry with default authentication if different */
 101         if (status && server->nfs_client->cl_rpcclient != server->client)
 102                 status = rpc_call_sync(server->nfs_client->cl_rpcclient, &msg, 0);
 103         dprintk("%s: reply getattr: %d\n", __func__, status);
 104         if (status)
 105                 return status;
 106         dprintk("%s: call statfs\n", __func__);
 107         msg.rpc_proc = &nfs_procedures[NFSPROC_STATFS];
 108         msg.rpc_resp = &fsinfo;
 109         status = rpc_call_sync(server->client, &msg, 0);
 110         /* Retry with default authentication if different */
 111         if (status && server->nfs_client->cl_rpcclient != server->client)
 112                 status = rpc_call_sync(server->nfs_client->cl_rpcclient, &msg, 0);
 113         dprintk("%s: reply statfs: %d\n", __func__, status);
 114         if (status)
 115                 return status;
 116         info->rtmax  = NFS_MAXDATA;
 117         info->rtpref = fsinfo.tsize;
 118         info->rtmult = fsinfo.bsize;
 119         info->wtmax  = NFS_MAXDATA;
 120         info->wtpref = fsinfo.tsize;
 121         info->wtmult = fsinfo.bsize;
 122         info->dtpref = fsinfo.tsize;
 123         info->maxfilesize = 0x7FFFFFFF;
 124         info->lease_time = 0;
 125         return 0;
 126 }
 127
 128 /*
 129  * One function for each procedure in the NFS protocol.
 130  */
 131 static int
 132 nfs_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle,
 133                 struct nfs_fattr *fattr)
 134 {
 135         struct rpc_message msg = {
 136                 .rpc_proc       = &nfs_procedures[NFSPROC_GETATTR],
 137                 .rpc_argp       = fhandle,
 138                 .rpc_resp       = fattr,
 139         };
 140         int     status;
 141
 142         dprintk("NFS call  getattr\n");
 143         nfs_fattr_init(fattr);
 144         status = rpc_call_sync(server->client, &msg, 0);
 145         dprintk("NFS reply getattr: %d\n", status);
 146         return status;
 147 }
 148
 149 static int
 150 nfs_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
 151                  struct iattr *sattr)
 152 {
 153         struct inode *inode = dentry->d_inode;
 154         struct nfs_sattrargs    arg = {
 155                 .fh     = NFS_FH(inode),
 156                 .sattr  = sattr
 157         };
 158         struct rpc_message msg = {
 159                 .rpc_proc       = &nfs_procedures[NFSPROC_SETATTR],
 160                 .rpc_argp       = &arg,
 161                 .rpc_resp       = fattr,
 162         };
 163         int     status;
 164
 165         /* Mask out the non-modebit related stuff from attr->ia_mode */
 166         sattr->ia_mode &= S_IALLUGO;
 167
 168         dprintk("NFS call  setattr\n");
 169         if (sattr->ia_valid & ATTR_FILE)
 170                 msg.rpc_cred = nfs_file_cred(sattr->ia_file);
 171         nfs_fattr_init(fattr);
 172         status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
 173         if (status == 0)
 174                 nfs_setattr_update_inode(inode, sattr);
 175         dprintk("NFS reply setattr: %d\n", status);
 176         return status;
 177 }
 178
 179 static int
 180 nfs_proc_lookup(struct rpc_clnt *clnt, struct inode *dir, struct qstr *name,
 181                 struct nfs_fh *fhandle, struct nfs_fattr *fattr)
 182 {
 183         struct nfs_diropargs    arg = {
 184                 .fh             = NFS_FH(dir),
 185                 .name           = name->name,
 186                 .len            = name->len
 187         };
 188         struct nfs_diropok      res = {
 189                 .fh             = fhandle,
 190                 .fattr          = fattr
 191         };
 192         struct rpc_message msg = {
 193                 .rpc_proc       = &nfs_procedures[NFSPROC_LOOKUP],
 194                 .rpc_argp       = &arg,
 195                 .rpc_resp       = &res,
 196         };
 197         int                     status;
 198
 199         dprintk("NFS call  lookup %s\n", name->name);
 200         nfs_fattr_init(fattr);
 201         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 202         dprintk("NFS reply lookup: %d\n", status);
 203         return status;
 204 }
 205
 206 static int nfs_proc_readlink(struct inode *inode, struct page *page,
 207                 unsigned int pgbase, unsigned int pglen)
 208 {
 209         struct nfs_readlinkargs args = {
 210                 .fh             = NFS_FH(inode),
 211                 .pgbase         = pgbase,
 212                 .pglen          = pglen,
 213                 .pages          = &page
 214         };
 215         struct rpc_message msg = {
 216                 .rpc_proc       = &nfs_procedures[NFSPROC_READLINK],
 217                 .rpc_argp       = &args,
 218         };
 219         int                     status;
 220
 221         dprintk("NFS call  readlink\n");
 222         status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
 223         dprintk("NFS reply readlink: %d\n", status);
 224         return status;
 225 }
 226
 227 struct nfs_createdata {
 228         struct nfs_createargs arg;
 229         struct nfs_diropok res;
 230         struct nfs_fh fhandle;
 231         struct nfs_fattr fattr;
 232 };
 233
 234 static struct nfs_createdata *nfs_alloc_createdata(struct inode *dir,
 235                 struct dentry *dentry, struct iattr *sattr)
 236 {
 237         struct nfs_createdata *data;
 238
 239         data = kmalloc(sizeof(*data), GFP_KERNEL);
 240
 241         if (data != NULL) {
 242                 data->arg.fh = NFS_FH(dir);
 243                 data->arg.name = dentry->d_name.name;
 244                 data->arg.len = dentry->d_name.len;
 245                 data->arg.sattr = sattr;
 246                 nfs_fattr_init(&data->fattr);
 247                 data->fhandle.size = 0;
 248                 data->res.fh = &data->fhandle;
 249                 data->res.fattr = &data->fattr;
 250         }
 251         return data;
 252 };
 253
 254 static void nfs_free_createdata(const struct nfs_createdata *data)
 255 {
 256         kfree(data);
 257 }
 258
 259 static int
 260 nfs_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
 261                 int flags, struct nfs_open_context *ctx)
 262 {
 263         struct nfs_createdata *data;
 264         struct rpc_message msg = {
 265                 .rpc_proc       = &nfs_procedures[NFSPROC_CREATE],
 266         };
 267         int status = -ENOMEM;
 268
 269         dprintk("NFS call  create %s\n", dentry->d_name.name);
 270         data = nfs_alloc_createdata(dir, dentry, sattr);
 271         if (data == NULL)
 272                 goto out;
 273         msg.rpc_argp = &data->arg;
 274         msg.rpc_resp = &data->res;
 275         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 276         nfs_mark_for_revalidate(dir);
 277         if (status == 0)
 278                 status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
 279         nfs_free_createdata(data);
 280 out:
 281         dprintk("NFS reply create: %d\n", status);
 282         return status;
 283 }
 284
 285 /*
 286  * In NFSv2, mknod is grafted onto the create call.
 287  */
 288 static int
 289 nfs_proc_mknod(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
 290                dev_t rdev)
 291 {
 292         struct nfs_createdata *data;
 293         struct rpc_message msg = {
 294                 .rpc_proc       = &nfs_procedures[NFSPROC_CREATE],
 295         };
 296         umode_t mode;
 297         int status = -ENOMEM;
 298
 299         dprintk("NFS call  mknod %s\n", dentry->d_name.name);
 300
 301         mode = sattr->ia_mode;
 302         if (S_ISFIFO(mode)) {
 303                 sattr->ia_mode = (mode & ~S_IFMT) | S_IFCHR;
 304                 sattr->ia_valid &= ~ATTR_SIZE;
 305         } else if (S_ISCHR(mode) || S_ISBLK(mode)) {
 306                 sattr->ia_valid |= ATTR_SIZE;
 307                 sattr->ia_size = new_encode_dev(rdev);/* get out your barf bag */
 308         }
 309
 310         data = nfs_alloc_createdata(dir, dentry, sattr);
 311         if (data == NULL)
 312                 goto out;
 313         msg.rpc_argp = &data->arg;
 314         msg.rpc_resp = &data->res;
 315
 316         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 317         nfs_mark_for_revalidate(dir);
 318
 319         if (status == -EINVAL && S_ISFIFO(mode)) {
 320                 sattr->ia_mode = mode;
 321                 nfs_fattr_init(data->res.fattr);
 322                 status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 323         }
 324         if (status == 0)
 325                 status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
 326         nfs_free_createdata(data);
 327 out:
 328         dprintk("NFS reply mknod: %d\n", status);
 329         return status;
 330 }
 331
 332 static int
 333 nfs_proc_remove(struct inode *dir, struct qstr *name)
 334 {
 335         struct nfs_removeargs arg = {
 336                 .fh = NFS_FH(dir),
 337                 .name.len = name->len,
 338                 .name.name = name->name,
 339         };
 340         struct rpc_message msg = {
 341                 .rpc_proc = &nfs_procedures[NFSPROC_REMOVE],
 342                 .rpc_argp = &arg,
 343         };
 344         int                     status;
 345
 346         dprintk("NFS call  remove %s\n", name->name);
 347         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 348         nfs_mark_for_revalidate(dir);
 349
 350         dprintk("NFS reply remove: %d\n", status);
 351         return status;
 352 }
 353
 354 static void
 355 nfs_proc_unlink_setup(struct rpc_message *msg, struct inode *dir)
 356 {
 357         msg->rpc_proc = &nfs_procedures[NFSPROC_REMOVE];
 358 }
 359
 360 static int nfs_proc_unlink_done(struct rpc_task *task, struct inode *dir)
 361 {
 362         if (nfs_async_handle_expired_key(task))
 363                 return 0;
 364         nfs_mark_for_revalidate(dir);
 365         return 1;
 366 }
 367
 368 static void
 369 nfs_proc_rename_setup(struct rpc_message *msg, struct inode *dir)
 370 {
 371         msg->rpc_proc = &nfs_procedures[NFSPROC_RENAME];
 372 }
 373
 374 static int
 375 nfs_proc_rename_done(struct rpc_task *task, struct inode *old_dir,
 376                      struct inode *new_dir)
 377 {
 378         if (nfs_async_handle_expired_key(task))
 379                 return 0;
 380         nfs_mark_for_revalidate(old_dir);
 381         nfs_mark_for_revalidate(new_dir);
 382         return 1;
 383 }
 384
 385 static int
 386 nfs_proc_rename(struct inode *old_dir, struct qstr *old_name,
 387                 struct inode *new_dir, struct qstr *new_name)
 388 {
 389         struct nfs_renameargs   arg = {
 390                 .old_dir        = NFS_FH(old_dir),
 391                 .old_name       = old_name,
 392                 .new_dir        = NFS_FH(new_dir),
 393                 .new_name       = new_name,
 394         };
 395         struct rpc_message msg = {
 396                 .rpc_proc       = &nfs_procedures[NFSPROC_RENAME],
 397                 .rpc_argp       = &arg,
 398         };
 399         int                     status;
 400
 401         dprintk("NFS call  rename %s -> %s\n", old_name->name, new_name->name);
 402         status = rpc_call_sync(NFS_CLIENT(old_dir), &msg, 0);
 403         nfs_mark_for_revalidate(old_dir);
 404         nfs_mark_for_revalidate(new_dir);
 405         dprintk("NFS reply rename: %d\n", status);
 406         return status;
 407 }
 408
 409 static int
 410 nfs_proc_link(struct inode *inode, struct inode *dir, struct qstr *name)
 411 {
 412         struct nfs_linkargs     arg = {
 413                 .fromfh         = NFS_FH(inode),
 414                 .tofh           = NFS_FH(dir),
 415                 .toname         = name->name,
 416                 .tolen          = name->len
 417         };
 418         struct rpc_message msg = {
 419                 .rpc_proc       = &nfs_procedures[NFSPROC_LINK],
 420                 .rpc_argp       = &arg,
 421         };
 422         int                     status;
 423
 424         dprintk("NFS call  link %s\n", name->name);
 425         status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
 426         nfs_mark_for_revalidate(inode);
 427         nfs_mark_for_revalidate(dir);
 428         dprintk("NFS reply link: %d\n", status);
 429         return status;
 430 }
 431
 432 static int
 433 nfs_proc_symlink(struct inode *dir, struct dentry *dentry, struct page *page,
 434                  unsigned int len, struct iattr *sattr)
 435 {
 436         struct nfs_fh *fh;
 437         struct nfs_fattr *fattr;
 438         struct nfs_symlinkargs  arg = {
 439                 .fromfh         = NFS_FH(dir),
 440                 .fromname       = dentry->d_name.name,
 441                 .fromlen        = dentry->d_name.len,
 442                 .pages          = &page,
 443                 .pathlen        = len,
 444                 .sattr          = sattr
 445         };
 446         struct rpc_message msg = {
 447                 .rpc_proc       = &nfs_procedures[NFSPROC_SYMLINK],
 448                 .rpc_argp       = &arg,
 449         };
 450         int status = -ENAMETOOLONG;
 451
 452         dprintk("NFS call  symlink %s\n", dentry->d_name.name);
 453
 454         if (len > NFS2_MAXPATHLEN)
 455                 goto out;
 456
 457         fh = nfs_alloc_fhandle();
 458         fattr = nfs_alloc_fattr();
 459         status = -ENOMEM;
 460         if (fh == NULL || fattr == NULL)
 461                 goto out_free;
 462
 463         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 464         nfs_mark_for_revalidate(dir);
 465
 466         /*
 467          * V2 SYMLINK requests don't return any attributes.  Setting the
 468          * filehandle size to zero indicates to nfs_instantiate that it
 469          * should fill in the data with a LOOKUP call on the wire.
 470          */
 471         if (status == 0)
 472                 status = nfs_instantiate(dentry, fh, fattr);
 473
 474 out_free:
 475         nfs_free_fattr(fattr);
 476         nfs_free_fhandle(fh);
 477 out:
 478         dprintk("NFS reply symlink: %d\n", status);
 479         return status;
 480 }
 481
 482 static int
 483 nfs_proc_mkdir(struct inode *dir, struct dentry *dentry, struct iattr *sattr)
 484 {
 485         struct nfs_createdata *data;
 486         struct rpc_message msg = {
 487                 .rpc_proc       = &nfs_procedures[NFSPROC_MKDIR],
 488         };
 489         int status = -ENOMEM;
 490
 491         dprintk("NFS call  mkdir %s\n", dentry->d_name.name);
 492         data = nfs_alloc_createdata(dir, dentry, sattr);
 493         if (data == NULL)
 494                 goto out;
 495         msg.rpc_argp = &data->arg;
 496         msg.rpc_resp = &data->res;
 497
 498         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 499         nfs_mark_for_revalidate(dir);
 500         if (status == 0)
 501                 status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
 502         nfs_free_createdata(data);
 503 out:
 504         dprintk("NFS reply mkdir: %d\n", status);
 505         return status;
 506 }
 507
 508 static int
 509 nfs_proc_rmdir(struct inode *dir, struct qstr *name)
 510 {
 511         struct nfs_diropargs    arg = {
 512                 .fh             = NFS_FH(dir),
 513                 .name           = name->name,
 514                 .len            = name->len
 515         };
 516         struct rpc_message msg = {
 517                 .rpc_proc       = &nfs_procedures[NFSPROC_RMDIR],
 518                 .rpc_argp       = &arg,
 519         };
 520         int                     status;
 521
 522         dprintk("NFS call  rmdir %s\n", name->name);
 523         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 524         nfs_mark_for_revalidate(dir);
 525         dprintk("NFS reply rmdir: %d\n", status);
 526         return status;
 527 }
 528
 529 /*
 530  * The READDIR implementation is somewhat hackish - we pass a temporary
 531  * buffer to the encode function, which installs it in the receive
 532  * the receive iovec. The decode function just parses the reply to make
 533  * sure it is syntactically correct; the entries itself are decoded
 534  * from nfs_readdir by calling the decode_entry function directly.
 535  */
 536 static int
 537 nfs_proc_readdir(struct dentry *dentry, struct rpc_cred *cred,
 538                  u64 cookie, struct page **pages, unsigned int count, int plus)
 539 {
 540         struct inode            *dir = dentry->d_inode;
 541         struct nfs_readdirargs  arg = {
 542                 .fh             = NFS_FH(dir),
 543                 .cookie         = cookie,
 544                 .count          = count,
 545                 .pages          = pages,
 546         };
 547         struct rpc_message      msg = {
 548                 .rpc_proc       = &nfs_procedures[NFSPROC_READDIR],
 549                 .rpc_argp       = &arg,
 550                 .rpc_cred       = cred,
 551         };
 552         int                     status;
 553
 554         dprintk("NFS call  readdir %d\n", (unsigned int)cookie);
 555         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 556
 557         nfs_invalidate_atime(dir);
 558
 559         dprintk("NFS reply readdir: %d\n", status);
 560         return status;
 561 }
 562
 563 static int
 564 nfs_proc_statfs(struct nfs_server *server, struct nfs_fh *fhandle,
 565                         struct nfs_fsstat *stat)
 566 {
 567         struct nfs2_fsstat fsinfo;
 568         struct rpc_message msg = {
 569                 .rpc_proc       = &nfs_procedures[NFSPROC_STATFS],
 570                 .rpc_argp       = fhandle,
 571                 .rpc_resp       = &fsinfo,
 572         };
 573         int     status;
 574
 575         dprintk("NFS call  statfs\n");
 576         nfs_fattr_init(stat->fattr);
 577         status = rpc_call_sync(server->client, &msg, 0);
 578         dprintk("NFS reply statfs: %d\n", status);
 579         if (status)
 580                 goto out;
 581         stat->tbytes = (u64)fsinfo.blocks * fsinfo.bsize;
 582         stat->fbytes = (u64)fsinfo.bfree  * fsinfo.bsize;
 583         stat->abytes = (u64)fsinfo.bavail * fsinfo.bsize;
 584         stat->tfiles = 0;
 585         stat->ffiles = 0;
 586         stat->afiles = 0;
 587 out:
 588         return status;
 589 }
 590
 591 static int
 592 nfs_proc_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle,
 593                         struct nfs_fsinfo *info)
 594 {
 595         struct nfs2_fsstat fsinfo;
 596         struct rpc_message msg = {
 597                 .rpc_proc       = &nfs_procedures[NFSPROC_STATFS],
 598                 .rpc_argp       = fhandle,
 599                 .rpc_resp       = &fsinfo,
 600         };
 601         int     status;
 602
 603         dprintk("NFS call  fsinfo\n");
 604         nfs_fattr_init(info->fattr);
 605         status = rpc_call_sync(server->client, &msg, 0);
 606         dprintk("NFS reply fsinfo: %d\n", status);
 607         if (status)
 608                 goto out;
 609         info->rtmax  = NFS_MAXDATA;
 610         info->rtpref = fsinfo.tsize;
 611         info->rtmult = fsinfo.bsize;
 612         info->wtmax  = NFS_MAXDATA;
 613         info->wtpref = fsinfo.tsize;
 614         info->wtmult = fsinfo.bsize;
 615         info->dtpref = fsinfo.tsize;
 616         info->maxfilesize = 0x7FFFFFFF;
 617         info->lease_time = 0;
 618 out:
 619         return status;
 620 }
 621
 622 static int
 623 nfs_proc_pathconf(struct nfs_server *server, struct nfs_fh *fhandle,
 624                   struct nfs_pathconf *info)
 625 {
 626         info->max_link = 0;
 627         info->max_namelen = NFS2_MAXNAMLEN;
 628         return 0;
 629 }
 630
 631 static int nfs_read_done(struct rpc_task *task, struct nfs_read_data *data)
 632 {
 633         if (nfs_async_handle_expired_key(task))
 634                 return -EAGAIN;
 635
 636         nfs_invalidate_atime(data->inode);
 637         if (task->tk_status >= 0) {
 638                 nfs_refresh_inode(data->inode, data->res.fattr);
 639                 /* Emulate the eof flag, which isn't normally needed in NFSv2
 640                  * as it is guaranteed to always return the file attributes
 641                  */
 642                 if (data->args.offset + data->args.count >= data->res.fattr->size)
 643                         data->res.eof = 1;
 644         }
 645         return 0;
 646 }
 647
 648 static void nfs_proc_read_setup(struct nfs_read_data *data, struct rpc_message *msg)
 649 {
 650         msg->rpc_proc = &nfs_procedures[NFSPROC_READ];
 651 }
 652
 653 static int nfs_write_done(struct rpc_task *task, struct nfs_write_data *data)
 654 {
 655         if (nfs_async_handle_expired_key(task))
 656                 return -EAGAIN;
 657
 658         if (task->tk_status >= 0)
 659                 nfs_post_op_update_inode_force_wcc(data->inode, data->res.fattr);
 660         return 0;
 661 }
 662
 663 static void nfs_proc_write_setup(struct nfs_write_data *data, struct rpc_message *msg)
 664 {
 665         /* Note: NFSv2 ignores @stable and always uses NFS_FILE_SYNC */
 666         data->args.stable = NFS_FILE_SYNC;
 667         msg->rpc_proc = &nfs_procedures[NFSPROC_WRITE];
 668 }
 669
 670 static void
 671 nfs_proc_commit_setup(struct nfs_write_data *data, struct rpc_message *msg)
 672 {
 673         BUG();
 674 }
 675
 676 static int
 677 nfs_proc_lock(struct file *filp, int cmd, struct file_lock *fl)
 678 {
 679         struct inode *inode = filp->f_path.dentry->d_inode;
 680
 681         return nlmclnt_proc(NFS_SERVER(inode)->nlm_host, cmd, fl);
 682 }
 683
 684 /* Helper functions for NFS lock bounds checking */
 685 #define NFS_LOCK32_OFFSET_MAX ((__s32)0x7fffffffUL)
 686 static int nfs_lock_check_bounds(const struct file_lock *fl)
 687 {
 688         __s32 start, end;
 689
 690         start = (__s32)fl->fl_start;
 691         if ((loff_t)start != fl->fl_start)
 692                 goto out_einval;
 693
 694         if (fl->fl_end != OFFSET_MAX) {
 695                 end = (__s32)fl->fl_end;
 696                 if ((loff_t)end != fl->fl_end)
 697                         goto out_einval;
 698         } else
 699                 end = NFS_LOCK32_OFFSET_MAX;
 700
 701         if (start < 0 || start > end)
 702                 goto out_einval;
 703         return 0;
 704 out_einval:
 705         return -EINVAL;
 706 }
 707
 708 const struct nfs_rpc_ops nfs_v2_clientops = {
 709         .version        = 2,                   /* protocol version */
 710         .dentry_ops     = &nfs_dentry_operations,
 711         .dir_inode_ops  = &nfs_dir_inode_operations,
 712         .file_inode_ops = &nfs_file_inode_operations,
 713         .file_ops       = &nfs_file_operations,
 714         .getroot        = nfs_proc_get_root,
 715         .getattr        = nfs_proc_getattr,
 716         .setattr        = nfs_proc_setattr,
 717         .lookup         = nfs_proc_lookup,
 718         .access         = NULL,                /* access */
 719         .readlink       = nfs_proc_readlink,
 720         .create         = nfs_proc_create,
 721         .remove         = nfs_proc_remove,
 722         .unlink_setup   = nfs_proc_unlink_setup,
 723         .unlink_done    = nfs_proc_unlink_done,
 724         .rename         = nfs_proc_rename,
 725         .rename_setup   = nfs_proc_rename_setup,
 726         .rename_done    = nfs_proc_rename_done,
 727         .link           = nfs_proc_link,
 728         .symlink        = nfs_proc_symlink,
 729         .mkdir          = nfs_proc_mkdir,
 730         .rmdir          = nfs_proc_rmdir,
 731         .readdir        = nfs_proc_readdir,
 732         .mknod          = nfs_proc_mknod,
 733         .statfs         = nfs_proc_statfs,
 734         .fsinfo         = nfs_proc_fsinfo,
 735         .pathconf       = nfs_proc_pathconf,
 736         .decode_dirent  = nfs2_decode_dirent,
 737         .read_setup     = nfs_proc_read_setup,
 738         .read_done      = nfs_read_done,
 739         .write_setup    = nfs_proc_write_setup,
 740         .write_done     = nfs_write_done,
 741         .commit_setup   = nfs_proc_commit_setup,
 742         .lock           = nfs_proc_lock,
 743         .lock_check_bounds = nfs_lock_check_bounds,
 744         .close_context  = nfs_close_context,
 745         .init_client    = nfs_init_client,
 746 };