fs/nfs/proc.c

   1 // SPDX-License-Identifier: GPL-2.0
   2 /*
   3  *  linux/fs/nfs/proc.c
   4  *
   5  *  Copyright (C) 1992, 1993, 1994  Rick Sladkey
   6  *
   7  *  OS-independent nfs remote procedure call functions
   8  *
   9  *  Tuned by Alan Cox <A.Cox@swansea.ac.uk> for >3K buffers
  10  *  so at last we can have decent(ish) throughput off a
  11  *  Sun server.
  12  *
  13  *  Coding optimized and cleaned up by Florian La Roche.
  14  *  Note: Error returns are optimized for NFS_OK, which isn't translated via
  15  *  nfs_stat_to_errno(), but happens to be already the right return code.
  16  *
  17  *  Also, the code currently doesn't check the size of the packet, when
  18  *  it decodes the packet.
  19  *
  20  *  Feel free to fix it and mail me the diffs if it worries you.
  21  *
  22  *  Completely rewritten to support the new RPC call interface;
  23  *  rewrote and moved the entire XDR stuff to xdr.c
  24  *  --Olaf Kirch June 1996
  25  *
  26  *  The code below initializes all auto variables explicitly, otherwise
  27  *  it will fail to work as a module (gcc generates a memset call for an
  28  *  incomplete struct).
  29  */
  30
  31 #include <linux/types.h>
  32 #include <linux/param.h>
  33 #include <linux/time.h>
  34 #include <linux/mm.h>
  35 #include <linux/errno.h>
  36 #include <linux/string.h>
  37 #include <linux/in.h>
  38 #include <linux/pagemap.h>
  39 #include <linux/sunrpc/clnt.h>
  40 #include <linux/nfs.h>
  41 #include <linux/nfs2.h>
  42 #include <linux/nfs_fs.h>
  43 #include <linux/nfs_page.h>
  44 #include <linux/lockd/bind.h>
  45 #include <linux/freezer.h>
  46 #include "internal.h"
  47
  48 #define NFSDBG_FACILITY         NFSDBG_PROC
  49
  50 /*
  51  * Bare-bones access to getattr: this is for nfs_read_super.
  52  */
  53 static int
  54 nfs_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
  55                   struct nfs_fsinfo *info)
  56 {
  57         struct nfs_fattr *fattr = info->fattr;
  58         struct nfs2_fsstat fsinfo;
  59         struct rpc_message msg = {
  60                 .rpc_proc       = &nfs_procedures[NFSPROC_GETATTR],
  61                 .rpc_argp       = fhandle,
  62                 .rpc_resp       = fattr,
  63         };
  64         int status;
  65
  66         dprintk("%s: call getattr\n", __func__);
  67         nfs_fattr_init(fattr);
  68         status = rpc_call_sync(server->client, &msg, 0);
  69         /* Retry with default authentication if different */
  70         if (status && server->nfs_client->cl_rpcclient != server->client)
  71                 status = rpc_call_sync(server->nfs_client->cl_rpcclient, &msg, 0);
  72         dprintk("%s: reply getattr: %d\n", __func__, status);
  73         if (status)
  74                 return status;
  75         dprintk("%s: call statfs\n", __func__);
  76         msg.rpc_proc = &nfs_procedures[NFSPROC_STATFS];
  77         msg.rpc_resp = &fsinfo;
  78         status = rpc_call_sync(server->client, &msg, 0);
  79         /* Retry with default authentication if different */
  80         if (status && server->nfs_client->cl_rpcclient != server->client)
  81                 status = rpc_call_sync(server->nfs_client->cl_rpcclient, &msg, 0);
  82         dprintk("%s: reply statfs: %d\n", __func__, status);
  83         if (status)
  84                 return status;
  85         info->rtmax  = NFS_MAXDATA;
  86         info->rtpref = fsinfo.tsize;
  87         info->rtmult = fsinfo.bsize;
  88         info->wtmax  = NFS_MAXDATA;
  89         info->wtpref = fsinfo.tsize;
  90         info->wtmult = fsinfo.bsize;
  91         info->dtpref = fsinfo.tsize;
  92         info->maxfilesize = 0x7FFFFFFF;
  93         info->lease_time = 0;
  94         info->change_attr_type = NFS4_CHANGE_TYPE_IS_UNDEFINED;
  95         info->xattr_support = 0;
  96         return 0;
  97 }
  98
  99 /*
 100  * One function for each procedure in the NFS protocol.
 101  */
 102 static int
 103 nfs_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle,
 104                 struct nfs_fattr *fattr, struct inode *inode)
 105 {
 106         struct rpc_message msg = {
 107                 .rpc_proc       = &nfs_procedures[NFSPROC_GETATTR],
 108                 .rpc_argp       = fhandle,
 109                 .rpc_resp       = fattr,
 110         };
 111         int     status;
 112         unsigned short task_flags = 0;
 113
 114         /* Is this is an attribute revalidation, subject to softreval? */
 115         if (inode && (server->flags & NFS_MOUNT_SOFTREVAL))
 116                 task_flags |= RPC_TASK_TIMEOUT;
 117
 118         dprintk("NFS call  getattr\n");
 119         nfs_fattr_init(fattr);
 120         status = rpc_call_sync(server->client, &msg, task_flags);
 121         dprintk("NFS reply getattr: %d\n", status);
 122         return status;
 123 }
 124
 125 static int
 126 nfs_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
 127                  struct iattr *sattr)
 128 {
 129         struct inode *inode = d_inode(dentry);
 130         struct nfs_sattrargs    arg = {
 131                 .fh     = NFS_FH(inode),
 132                 .sattr  = sattr
 133         };
 134         struct rpc_message msg = {
 135                 .rpc_proc       = &nfs_procedures[NFSPROC_SETATTR],
 136                 .rpc_argp       = &arg,
 137                 .rpc_resp       = fattr,
 138         };
 139         int     status;
 140
 141         /* Mask out the non-modebit related stuff from attr->ia_mode */
 142         sattr->ia_mode &= S_IALLUGO;
 143
 144         dprintk("NFS call  setattr\n");
 145         if (sattr->ia_valid & ATTR_FILE)
 146                 msg.rpc_cred = nfs_file_cred(sattr->ia_file);
 147         nfs_fattr_init(fattr);
 148         status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
 149         if (status == 0)
 150                 nfs_setattr_update_inode(inode, sattr, fattr);
 151         dprintk("NFS reply setattr: %d\n", status);
 152         return status;
 153 }
 154
 155 static int
 156 nfs_proc_lookup(struct inode *dir, struct dentry *dentry,
 157                 struct nfs_fh *fhandle, struct nfs_fattr *fattr)
 158 {
 159         struct nfs_diropargs    arg = {
 160                 .fh             = NFS_FH(dir),
 161                 .name           = dentry->d_name.name,
 162                 .len            = dentry->d_name.len
 163         };
 164         struct nfs_diropok      res = {
 165                 .fh             = fhandle,
 166                 .fattr          = fattr
 167         };
 168         struct rpc_message msg = {
 169                 .rpc_proc       = &nfs_procedures[NFSPROC_LOOKUP],
 170                 .rpc_argp       = &arg,
 171                 .rpc_resp       = &res,
 172         };
 173         int                     status;
 174         unsigned short task_flags = 0;
 175
 176         /* Is this is an attribute revalidation, subject to softreval? */
 177         if (nfs_lookup_is_soft_revalidate(dentry))
 178                 task_flags |= RPC_TASK_TIMEOUT;
 179
 180         dprintk("NFS call  lookup %pd2\n", dentry);
 181         nfs_fattr_init(fattr);
 182         status = rpc_call_sync(NFS_CLIENT(dir), &msg, task_flags);
 183         dprintk("NFS reply lookup: %d\n", status);
 184         return status;
 185 }
 186
 187 static int nfs_proc_readlink(struct inode *inode, struct page *page,
 188                 unsigned int pgbase, unsigned int pglen)
 189 {
 190         struct nfs_readlinkargs args = {
 191                 .fh             = NFS_FH(inode),
 192                 .pgbase         = pgbase,
 193                 .pglen          = pglen,
 194                 .pages          = &page
 195         };
 196         struct rpc_message msg = {
 197                 .rpc_proc       = &nfs_procedures[NFSPROC_READLINK],
 198                 .rpc_argp       = &args,
 199         };
 200         int                     status;
 201
 202         dprintk("NFS call  readlink\n");
 203         status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
 204         dprintk("NFS reply readlink: %d\n", status);
 205         return status;
 206 }
 207
 208 struct nfs_createdata {
 209         struct nfs_createargs arg;
 210         struct nfs_diropok res;
 211         struct nfs_fh fhandle;
 212         struct nfs_fattr fattr;
 213 };
 214
 215 static struct nfs_createdata *nfs_alloc_createdata(struct inode *dir,
 216                 struct dentry *dentry, struct iattr *sattr)
 217 {
 218         struct nfs_createdata *data;
 219
 220         data = kmalloc(sizeof(*data), GFP_KERNEL);
 221
 222         if (data != NULL) {
 223                 data->arg.fh = NFS_FH(dir);
 224                 data->arg.name = dentry->d_name.name;
 225                 data->arg.len = dentry->d_name.len;
 226                 data->arg.sattr = sattr;
 227                 nfs_fattr_init(&data->fattr);
 228                 data->fhandle.size = 0;
 229                 data->res.fh = &data->fhandle;
 230                 data->res.fattr = &data->fattr;
 231         }
 232         return data;
 233 };
 234
 235 static void nfs_free_createdata(const struct nfs_createdata *data)
 236 {
 237         kfree(data);
 238 }
 239
 240 static int
 241 nfs_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
 242                 int flags)
 243 {
 244         struct nfs_createdata *data;
 245         struct rpc_message msg = {
 246                 .rpc_proc       = &nfs_procedures[NFSPROC_CREATE],
 247         };
 248         int status = -ENOMEM;
 249
 250         dprintk("NFS call  create %pd\n", dentry);
 251         data = nfs_alloc_createdata(dir, dentry, sattr);
 252         if (data == NULL)
 253                 goto out;
 254         msg.rpc_argp = &data->arg;
 255         msg.rpc_resp = &data->res;
 256         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 257         nfs_mark_for_revalidate(dir);
 258         if (status == 0)
 259                 status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
 260         nfs_free_createdata(data);
 261 out:
 262         dprintk("NFS reply create: %d\n", status);
 263         return status;
 264 }
 265
 266 /*
 267  * In NFSv2, mknod is grafted onto the create call.
 268  */
 269 static int
 270 nfs_proc_mknod(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
 271                dev_t rdev)
 272 {
 273         struct nfs_createdata *data;
 274         struct rpc_message msg = {
 275                 .rpc_proc       = &nfs_procedures[NFSPROC_CREATE],
 276         };
 277         umode_t mode;
 278         int status = -ENOMEM;
 279
 280         dprintk("NFS call  mknod %pd\n", dentry);
 281
 282         mode = sattr->ia_mode;
 283         if (S_ISFIFO(mode)) {
 284                 sattr->ia_mode = (mode & ~S_IFMT) | S_IFCHR;
 285                 sattr->ia_valid &= ~ATTR_SIZE;
 286         } else if (S_ISCHR(mode) || S_ISBLK(mode)) {
 287                 sattr->ia_valid |= ATTR_SIZE;
 288                 sattr->ia_size = new_encode_dev(rdev);/* get out your barf bag */
 289         }
 290
 291         data = nfs_alloc_createdata(dir, dentry, sattr);
 292         if (data == NULL)
 293                 goto out;
 294         msg.rpc_argp = &data->arg;
 295         msg.rpc_resp = &data->res;
 296
 297         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 298         nfs_mark_for_revalidate(dir);
 299
 300         if (status == -EINVAL && S_ISFIFO(mode)) {
 301                 sattr->ia_mode = mode;
 302                 nfs_fattr_init(data->res.fattr);
 303                 status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 304         }
 305         if (status == 0)
 306                 status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
 307         nfs_free_createdata(data);
 308 out:
 309         dprintk("NFS reply mknod: %d\n", status);
 310         return status;
 311 }
 312
 313 static int
 314 nfs_proc_remove(struct inode *dir, struct dentry *dentry)
 315 {
 316         struct nfs_removeargs arg = {
 317                 .fh = NFS_FH(dir),
 318                 .name = dentry->d_name,
 319         };
 320         struct rpc_message msg = {
 321                 .rpc_proc = &nfs_procedures[NFSPROC_REMOVE],
 322                 .rpc_argp = &arg,
 323         };
 324         int                     status;
 325
 326         dprintk("NFS call  remove %pd2\n",dentry);
 327         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 328         nfs_mark_for_revalidate(dir);
 329
 330         dprintk("NFS reply remove: %d\n", status);
 331         return status;
 332 }
 333
 334 static void
 335 nfs_proc_unlink_setup(struct rpc_message *msg,
 336                 struct dentry *dentry,
 337                 struct inode *inode)
 338 {
 339         msg->rpc_proc = &nfs_procedures[NFSPROC_REMOVE];
 340 }
 341
 342 static void nfs_proc_unlink_rpc_prepare(struct rpc_task *task, struct nfs_unlinkdata *data)
 343 {
 344         rpc_call_start(task);
 345 }
 346
 347 static int nfs_proc_unlink_done(struct rpc_task *task, struct inode *dir)
 348 {
 349         nfs_mark_for_revalidate(dir);
 350         return 1;
 351 }
 352
 353 static void
 354 nfs_proc_rename_setup(struct rpc_message *msg,
 355                 struct dentry *old_dentry,
 356                 struct dentry *new_dentry)
 357 {
 358         msg->rpc_proc = &nfs_procedures[NFSPROC_RENAME];
 359 }
 360
 361 static void nfs_proc_rename_rpc_prepare(struct rpc_task *task, struct nfs_renamedata *data)
 362 {
 363         rpc_call_start(task);
 364 }
 365
 366 static int
 367 nfs_proc_rename_done(struct rpc_task *task, struct inode *old_dir,
 368                      struct inode *new_dir)
 369 {
 370         nfs_mark_for_revalidate(old_dir);
 371         nfs_mark_for_revalidate(new_dir);
 372         return 1;
 373 }
 374
 375 static int
 376 nfs_proc_link(struct inode *inode, struct inode *dir, const struct qstr *name)
 377 {
 378         struct nfs_linkargs     arg = {
 379                 .fromfh         = NFS_FH(inode),
 380                 .tofh           = NFS_FH(dir),
 381                 .toname         = name->name,
 382                 .tolen          = name->len
 383         };
 384         struct rpc_message msg = {
 385                 .rpc_proc       = &nfs_procedures[NFSPROC_LINK],
 386                 .rpc_argp       = &arg,
 387         };
 388         int                     status;
 389
 390         dprintk("NFS call  link %s\n", name->name);
 391         status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
 392         nfs_mark_for_revalidate(inode);
 393         nfs_mark_for_revalidate(dir);
 394         dprintk("NFS reply link: %d\n", status);
 395         return status;
 396 }
 397
 398 static int
 399 nfs_proc_symlink(struct inode *dir, struct dentry *dentry, struct folio *folio,
 400                  unsigned int len, struct iattr *sattr)
 401 {
 402         struct page *page = &folio->page;
 403         struct nfs_fh *fh;
 404         struct nfs_fattr *fattr;
 405         struct nfs_symlinkargs  arg = {
 406                 .fromfh         = NFS_FH(dir),
 407                 .fromname       = dentry->d_name.name,
 408                 .fromlen        = dentry->d_name.len,
 409                 .pages          = &page,
 410                 .pathlen        = len,
 411                 .sattr          = sattr
 412         };
 413         struct rpc_message msg = {
 414                 .rpc_proc       = &nfs_procedures[NFSPROC_SYMLINK],
 415                 .rpc_argp       = &arg,
 416         };
 417         int status = -ENAMETOOLONG;
 418
 419         dprintk("NFS call  symlink %pd\n", dentry);
 420
 421         if (len > NFS2_MAXPATHLEN)
 422                 goto out;
 423
 424         fh = nfs_alloc_fhandle();
 425         fattr = nfs_alloc_fattr();
 426         status = -ENOMEM;
 427         if (fh == NULL || fattr == NULL)
 428                 goto out_free;
 429
 430         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 431         nfs_mark_for_revalidate(dir);
 432
 433         /*
 434          * V2 SYMLINK requests don't return any attributes.  Setting the
 435          * filehandle size to zero indicates to nfs_instantiate that it
 436          * should fill in the data with a LOOKUP call on the wire.
 437          */
 438         if (status == 0)
 439                 status = nfs_instantiate(dentry, fh, fattr);
 440
 441 out_free:
 442         nfs_free_fattr(fattr);
 443         nfs_free_fhandle(fh);
 444 out:
 445         dprintk("NFS reply symlink: %d\n", status);
 446         return status;
 447 }
 448
 449 static int
 450 nfs_proc_mkdir(struct inode *dir, struct dentry *dentry, struct iattr *sattr)
 451 {
 452         struct nfs_createdata *data;
 453         struct rpc_message msg = {
 454                 .rpc_proc       = &nfs_procedures[NFSPROC_MKDIR],
 455         };
 456         int status = -ENOMEM;
 457
 458         dprintk("NFS call  mkdir %pd\n", dentry);
 459         data = nfs_alloc_createdata(dir, dentry, sattr);
 460         if (data == NULL)
 461                 goto out;
 462         msg.rpc_argp = &data->arg;
 463         msg.rpc_resp = &data->res;
 464
 465         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 466         nfs_mark_for_revalidate(dir);
 467         if (status == 0)
 468                 status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
 469         nfs_free_createdata(data);
 470 out:
 471         dprintk("NFS reply mkdir: %d\n", status);
 472         return status;
 473 }
 474
 475 static int
 476 nfs_proc_rmdir(struct inode *dir, const struct qstr *name)
 477 {
 478         struct nfs_diropargs    arg = {
 479                 .fh             = NFS_FH(dir),
 480                 .name           = name->name,
 481                 .len            = name->len
 482         };
 483         struct rpc_message msg = {
 484                 .rpc_proc       = &nfs_procedures[NFSPROC_RMDIR],
 485                 .rpc_argp       = &arg,
 486         };
 487         int                     status;
 488
 489         dprintk("NFS call  rmdir %s\n", name->name);
 490         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 491         nfs_mark_for_revalidate(dir);
 492         dprintk("NFS reply rmdir: %d\n", status);
 493         return status;
 494 }
 495
 496 /*
 497  * The READDIR implementation is somewhat hackish - we pass a temporary
 498  * buffer to the encode function, which installs it in the receive
 499  * the receive iovec. The decode function just parses the reply to make
 500  * sure it is syntactically correct; the entries itself are decoded
 501  * from nfs_readdir by calling the decode_entry function directly.
 502  */
 503 static int nfs_proc_readdir(struct nfs_readdir_arg *nr_arg,
 504                             struct nfs_readdir_res *nr_res)
 505 {
 506         struct inode            *dir = d_inode(nr_arg->dentry);
 507         struct nfs_readdirargs  arg = {
 508                 .fh             = NFS_FH(dir),
 509                 .cookie         = nr_arg->cookie,
 510                 .count          = nr_arg->page_len,
 511                 .pages          = nr_arg->pages,
 512         };
 513         struct rpc_message      msg = {
 514                 .rpc_proc       = &nfs_procedures[NFSPROC_READDIR],
 515                 .rpc_argp       = &arg,
 516                 .rpc_cred       = nr_arg->cred,
 517         };
 518         int                     status;
 519
 520         dprintk("NFS call  readdir %llu\n", (unsigned long long)nr_arg->cookie);
 521         status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
 522         nr_res->verf[0] = nr_res->verf[1] = 0;
 523
 524         nfs_invalidate_atime(dir);
 525
 526         dprintk("NFS reply readdir: %d\n", status);
 527         return status;
 528 }
 529
 530 static int
 531 nfs_proc_statfs(struct nfs_server *server, struct nfs_fh *fhandle,
 532                         struct nfs_fsstat *stat)
 533 {
 534         struct nfs2_fsstat fsinfo;
 535         struct rpc_message msg = {
 536                 .rpc_proc       = &nfs_procedures[NFSPROC_STATFS],
 537                 .rpc_argp       = fhandle,
 538                 .rpc_resp       = &fsinfo,
 539         };
 540         int     status;
 541
 542         dprintk("NFS call  statfs\n");
 543         nfs_fattr_init(stat->fattr);
 544         status = rpc_call_sync(server->client, &msg, 0);
 545         dprintk("NFS reply statfs: %d\n", status);
 546         if (status)
 547                 goto out;
 548         stat->tbytes = (u64)fsinfo.blocks * fsinfo.bsize;
 549         stat->fbytes = (u64)fsinfo.bfree  * fsinfo.bsize;
 550         stat->abytes = (u64)fsinfo.bavail * fsinfo.bsize;
 551         stat->tfiles = 0;
 552         stat->ffiles = 0;
 553         stat->afiles = 0;
 554 out:
 555         return status;
 556 }
 557
 558 static int
 559 nfs_proc_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle,
 560                         struct nfs_fsinfo *info)
 561 {
 562         struct nfs2_fsstat fsinfo;
 563         struct rpc_message msg = {
 564                 .rpc_proc       = &nfs_procedures[NFSPROC_STATFS],
 565                 .rpc_argp       = fhandle,
 566                 .rpc_resp       = &fsinfo,
 567         };
 568         int     status;
 569
 570         dprintk("NFS call  fsinfo\n");
 571         nfs_fattr_init(info->fattr);
 572         status = rpc_call_sync(server->client, &msg, 0);
 573         dprintk("NFS reply fsinfo: %d\n", status);
 574         if (status)
 575                 goto out;
 576         info->rtmax  = NFS_MAXDATA;
 577         info->rtpref = fsinfo.tsize;
 578         info->rtmult = fsinfo.bsize;
 579         info->wtmax  = NFS_MAXDATA;
 580         info->wtpref = fsinfo.tsize;
 581         info->wtmult = fsinfo.bsize;
 582         info->dtpref = fsinfo.tsize;
 583         info->maxfilesize = 0x7FFFFFFF;
 584         info->lease_time = 0;
 585 out:
 586         return status;
 587 }
 588
 589 static int
 590 nfs_proc_pathconf(struct nfs_server *server, struct nfs_fh *fhandle,
 591                   struct nfs_pathconf *info)
 592 {
 593         info->max_link = 0;
 594         info->max_namelen = NFS2_MAXNAMLEN;
 595         return 0;
 596 }
 597
 598 static int nfs_read_done(struct rpc_task *task, struct nfs_pgio_header *hdr)
 599 {
 600         struct inode *inode = hdr->inode;
 601
 602         nfs_invalidate_atime(inode);
 603         if (task->tk_status >= 0) {
 604                 nfs_refresh_inode(inode, hdr->res.fattr);
 605                 /* Emulate the eof flag, which isn't normally needed in NFSv2
 606                  * as it is guaranteed to always return the file attributes
 607                  */
 608                 if ((hdr->res.count == 0 && hdr->args.count > 0) ||
 609                     hdr->args.offset + hdr->res.count >= hdr->res.fattr->size)
 610                         hdr->res.eof = 1;
 611         }
 612         return 0;
 613 }
 614
 615 static void nfs_proc_read_setup(struct nfs_pgio_header *hdr,
 616                                 struct rpc_message *msg)
 617 {
 618         msg->rpc_proc = &nfs_procedures[NFSPROC_READ];
 619 }
 620
 621 static int nfs_proc_pgio_rpc_prepare(struct rpc_task *task,
 622                                      struct nfs_pgio_header *hdr)
 623 {
 624         rpc_call_start(task);
 625         return 0;
 626 }
 627
 628 static int nfs_write_done(struct rpc_task *task, struct nfs_pgio_header *hdr)
 629 {
 630         if (task->tk_status >= 0) {
 631                 hdr->res.count = hdr->args.count;
 632                 nfs_writeback_update_inode(hdr);
 633         }
 634         return 0;
 635 }
 636
 637 static void nfs_proc_write_setup(struct nfs_pgio_header *hdr,
 638                                  struct rpc_message *msg,
 639                                  struct rpc_clnt **clnt)
 640 {
 641         /* Note: NFSv2 ignores @stable and always uses NFS_FILE_SYNC */
 642         hdr->args.stable = NFS_FILE_SYNC;
 643         msg->rpc_proc = &nfs_procedures[NFSPROC_WRITE];
 644 }
 645
 646 static void nfs_proc_commit_rpc_prepare(struct rpc_task *task, struct nfs_commit_data *data)
 647 {
 648         BUG();
 649 }
 650
 651 static void
 652 nfs_proc_commit_setup(struct nfs_commit_data *data, struct rpc_message *msg,
 653                         struct rpc_clnt **clnt)
 654 {
 655         BUG();
 656 }
 657
 658 static int
 659 nfs_proc_lock(struct file *filp, int cmd, struct file_lock *fl)
 660 {
 661         struct inode *inode = file_inode(filp);
 662
 663         return nlmclnt_proc(NFS_SERVER(inode)->nlm_host, cmd, fl, NULL);
 664 }
 665
 666 /* Helper functions for NFS lock bounds checking */
 667 #define NFS_LOCK32_OFFSET_MAX ((__s32)0x7fffffffUL)
 668 static int nfs_lock_check_bounds(const struct file_lock *fl)
 669 {
 670         __s32 start, end;
 671
 672         start = (__s32)fl->fl_start;
 673         if ((loff_t)start != fl->fl_start)
 674                 goto out_einval;
 675
 676         if (fl->fl_end != OFFSET_MAX) {
 677                 end = (__s32)fl->fl_end;
 678                 if ((loff_t)end != fl->fl_end)
 679                         goto out_einval;
 680         } else
 681                 end = NFS_LOCK32_OFFSET_MAX;
 682
 683         if (start < 0 || start > end)
 684                 goto out_einval;
 685         return 0;
 686 out_einval:
 687         return -EINVAL;
 688 }
 689
 690 static int nfs_have_delegation(struct inode *inode, fmode_t type, int flags)
 691 {
 692         return 0;
 693 }
 694
 695 static int nfs_return_delegation(struct inode *inode)
 696 {
 697         if (S_ISREG(inode->i_mode))
 698                 nfs_wb_all(inode);
 699         return 0;
 700 }
 701
 702 static const struct inode_operations nfs_dir_inode_operations = {
 703         .create         = nfs_create,
 704         .lookup         = nfs_lookup,
 705         .atomic_open    = nfs_atomic_open_v23,
 706         .link           = nfs_link,
 707         .unlink         = nfs_unlink,
 708         .symlink        = nfs_symlink,
 709         .mkdir          = nfs_mkdir,
 710         .rmdir          = nfs_rmdir,
 711         .mknod          = nfs_mknod,
 712         .rename         = nfs_rename,
 713         .permission     = nfs_permission,
 714         .getattr        = nfs_getattr,
 715         .setattr        = nfs_setattr,
 716 };
 717
 718 static const struct inode_operations nfs_file_inode_operations = {
 719         .permission     = nfs_permission,
 720         .getattr        = nfs_getattr,
 721         .setattr        = nfs_setattr,
 722 };
 723
 724 const struct nfs_rpc_ops nfs_v2_clientops = {
 725         .version        = 2,                   /* protocol version */
 726         .dentry_ops     = &nfs_dentry_operations,
 727         .dir_inode_ops  = &nfs_dir_inode_operations,
 728         .file_inode_ops = &nfs_file_inode_operations,
 729         .file_ops       = &nfs_file_operations,
 730         .getroot        = nfs_proc_get_root,
 731         .submount       = nfs_submount,
 732         .try_get_tree   = nfs_try_get_tree,
 733         .getattr        = nfs_proc_getattr,
 734         .setattr        = nfs_proc_setattr,
 735         .lookup         = nfs_proc_lookup,
 736         .access         = NULL,                /* access */
 737         .readlink       = nfs_proc_readlink,
 738         .create         = nfs_proc_create,
 739         .remove         = nfs_proc_remove,
 740         .unlink_setup   = nfs_proc_unlink_setup,
 741         .unlink_rpc_prepare = nfs_proc_unlink_rpc_prepare,
 742         .unlink_done    = nfs_proc_unlink_done,
 743         .rename_setup   = nfs_proc_rename_setup,
 744         .rename_rpc_prepare = nfs_proc_rename_rpc_prepare,
 745         .rename_done    = nfs_proc_rename_done,
 746         .link           = nfs_proc_link,
 747         .symlink        = nfs_proc_symlink,
 748         .mkdir          = nfs_proc_mkdir,
 749         .rmdir          = nfs_proc_rmdir,
 750         .readdir        = nfs_proc_readdir,
 751         .mknod          = nfs_proc_mknod,
 752         .statfs         = nfs_proc_statfs,
 753         .fsinfo         = nfs_proc_fsinfo,
 754         .pathconf       = nfs_proc_pathconf,
 755         .decode_dirent  = nfs2_decode_dirent,
 756         .pgio_rpc_prepare = nfs_proc_pgio_rpc_prepare,
 757         .read_setup     = nfs_proc_read_setup,
 758         .read_done      = nfs_read_done,
 759         .write_setup    = nfs_proc_write_setup,
 760         .write_done     = nfs_write_done,
 761         .commit_setup   = nfs_proc_commit_setup,
 762         .commit_rpc_prepare = nfs_proc_commit_rpc_prepare,
 763         .lock           = nfs_proc_lock,
 764         .lock_check_bounds = nfs_lock_check_bounds,
 765         .close_context  = nfs_close_context,
 766         .have_delegation = nfs_have_delegation,
 767         .return_delegation = nfs_return_delegation,
 768         .alloc_client   = nfs_alloc_client,
 769         .init_client    = nfs_init_client,
 770         .free_client    = nfs_free_client,
 771         .create_server  = nfs_create_server,
 772         .clone_server   = nfs_clone_server,
 773 };