linux/fs/nfs/proc.c
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   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 */
  54static int
  55nfs_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
  70static int
  71nfs_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 */
  84static int
  85nfs_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 */
 131static int
 132nfs_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
 149static int
 150nfs_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
 179static int
 180nfs_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
 206static 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
 227struct nfs_createdata {
 228        struct nfs_createargs arg;
 229        struct nfs_diropok res;
 230        struct nfs_fh fhandle;
 231        struct nfs_fattr fattr;
 232};
 233
 234static 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
 254static void nfs_free_createdata(const struct nfs_createdata *data)
 255{
 256        kfree(data);
 257}
 258
 259static int
 260nfs_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);
 280out:
 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 */
 288static int
 289nfs_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);
 327out:
 328        dprintk("NFS reply mknod: %d\n", status);
 329        return status;
 330}
 331  
 332static int
 333nfs_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
 354static void
 355nfs_proc_unlink_setup(struct rpc_message *msg, struct inode *dir)
 356{
 357        msg->rpc_proc = &nfs_procedures[NFSPROC_REMOVE];
 358}
 359
 360static 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
 368static void
 369nfs_proc_rename_setup(struct rpc_message *msg, struct inode *dir)
 370{
 371        msg->rpc_proc = &nfs_procedures[NFSPROC_RENAME];
 372}
 373
 374static int
 375nfs_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
 385static int
 386nfs_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
 409static int
 410nfs_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
 432static int
 433nfs_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
 474out_free:
 475        nfs_free_fattr(fattr);
 476        nfs_free_fhandle(fh);
 477out:
 478        dprintk("NFS reply symlink: %d\n", status);
 479        return status;
 480}
 481
 482static int
 483nfs_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);
 503out:
 504        dprintk("NFS reply mkdir: %d\n", status);
 505        return status;
 506}
 507
 508static int
 509nfs_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 */
 536static int
 537nfs_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
 563static int
 564nfs_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;
 587out:
 588        return status;
 589}
 590
 591static int
 592nfs_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;
 618out:
 619        return status;
 620}
 621
 622static int
 623nfs_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
 631static 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
 648static 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
 653static 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
 663static 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
 670static void
 671nfs_proc_commit_setup(struct nfs_write_data *data, struct rpc_message *msg)
 672{
 673        BUG();
 674}
 675
 676static int
 677nfs_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)
 686static 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;
 704out_einval:
 705        return -EINVAL;
 706}
 707
 708const 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        .getroot        = nfs_proc_get_root,
 714        .getattr        = nfs_proc_getattr,
 715        .setattr        = nfs_proc_setattr,
 716        .lookup         = nfs_proc_lookup,
 717        .access         = NULL,                /* access */
 718        .readlink       = nfs_proc_readlink,
 719        .create         = nfs_proc_create,
 720        .remove         = nfs_proc_remove,
 721        .unlink_setup   = nfs_proc_unlink_setup,
 722        .unlink_done    = nfs_proc_unlink_done,
 723        .rename         = nfs_proc_rename,
 724        .rename_setup   = nfs_proc_rename_setup,
 725        .rename_done    = nfs_proc_rename_done,
 726        .link           = nfs_proc_link,
 727        .symlink        = nfs_proc_symlink,
 728        .mkdir          = nfs_proc_mkdir,
 729        .rmdir          = nfs_proc_rmdir,
 730        .readdir        = nfs_proc_readdir,
 731        .mknod          = nfs_proc_mknod,
 732        .statfs         = nfs_proc_statfs,
 733        .fsinfo         = nfs_proc_fsinfo,
 734        .pathconf       = nfs_proc_pathconf,
 735        .decode_dirent  = nfs2_decode_dirent,
 736        .read_setup     = nfs_proc_read_setup,
 737        .read_done      = nfs_read_done,
 738        .write_setup    = nfs_proc_write_setup,
 739        .write_done     = nfs_write_done,
 740        .commit_setup   = nfs_proc_commit_setup,
 741        .lock           = nfs_proc_lock,
 742        .lock_check_bounds = nfs_lock_check_bounds,
 743        .close_context  = nfs_close_context,
 744        .init_client    = nfs_init_client,
 745};
 746