aboutsummaryrefslogblamecommitdiffstats
path: root/fs/nfs/nfs3xdr.c
blob: 0250269e9753a46bd4decb4494dacc2f6676b833 (plain) (tree)
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634






















                                                                  
                         
                     





                                                        

















































                                                                                    




                                                                    
















































































                                                                       

                                                    






                                                             







                                            
                                                        
































































































































































































































































































































































































































































                                                                                         











































                                                                          
                                                                              






















                                                                  






























































































































































































































































































































































                                                                                           















































                                                                             









                                                                                 


                                                                         



























                                                        
                                                              


                                                 







                                                                            
                                   






                                                                            
                                   









                                                                 
/*
 * linux/fs/nfs/nfs3xdr.c
 *
 * XDR functions to encode/decode NFSv3 RPC arguments and results.
 *
 * Copyright (C) 1996, 1997 Olaf Kirch
 */

#include <linux/param.h>
#include <linux/time.h>
#include <linux/mm.h>
#include <linux/slab.h>
#include <linux/utsname.h>
#include <linux/errno.h>
#include <linux/string.h>
#include <linux/in.h>
#include <linux/pagemap.h>
#include <linux/proc_fs.h>
#include <linux/kdev_t.h>
#include <linux/sunrpc/clnt.h>
#include <linux/nfs.h>
#include <linux/nfs3.h>
#include <linux/nfs_fs.h>
#include <linux/nfsacl.h>
#include "internal.h"

#define NFSDBG_FACILITY		NFSDBG_XDR

/* Mapping from NFS error code to "errno" error code. */
#define errno_NFSERR_IO		EIO

/*
 * Declare the space requirements for NFS arguments and replies as
 * number of 32bit-words
 */
#define NFS3_fhandle_sz		(1+16)
#define NFS3_fh_sz		(NFS3_fhandle_sz)	/* shorthand */
#define NFS3_sattr_sz		(15)
#define NFS3_filename_sz	(1+(NFS3_MAXNAMLEN>>2))
#define NFS3_path_sz		(1+(NFS3_MAXPATHLEN>>2))
#define NFS3_fattr_sz		(21)
#define NFS3_wcc_attr_sz		(6)
#define NFS3_pre_op_attr_sz	(1+NFS3_wcc_attr_sz)
#define NFS3_post_op_attr_sz	(1+NFS3_fattr_sz)
#define NFS3_wcc_data_sz		(NFS3_pre_op_attr_sz+NFS3_post_op_attr_sz)
#define NFS3_fsstat_sz		
#define NFS3_fsinfo_sz		
#define NFS3_pathconf_sz		
#define NFS3_entry_sz		(NFS3_filename_sz+3)

#define NFS3_sattrargs_sz	(NFS3_fh_sz+NFS3_sattr_sz+3)
#define NFS3_diropargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
#define NFS3_accessargs_sz	(NFS3_fh_sz+1)
#define NFS3_readlinkargs_sz	(NFS3_fh_sz)
#define NFS3_readargs_sz	(NFS3_fh_sz+3)
#define NFS3_writeargs_sz	(NFS3_fh_sz+5)
#define NFS3_createargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
#define NFS3_mkdirargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
#define NFS3_symlinkargs_sz	(NFS3_diropargs_sz+NFS3_path_sz+NFS3_sattr_sz)
#define NFS3_mknodargs_sz	(NFS3_diropargs_sz+2+NFS3_sattr_sz)
#define NFS3_renameargs_sz	(NFS3_diropargs_sz+NFS3_diropargs_sz)
#define NFS3_linkargs_sz		(NFS3_fh_sz+NFS3_diropargs_sz)
#define NFS3_readdirargs_sz	(NFS3_fh_sz+2)
#define NFS3_commitargs_sz	(NFS3_fh_sz+3)

#define NFS3_attrstat_sz	(1+NFS3_fattr_sz)
#define NFS3_wccstat_sz		(1+NFS3_wcc_data_sz)
#define NFS3_lookupres_sz	(1+NFS3_fh_sz+(2 * NFS3_post_op_attr_sz))
#define NFS3_accessres_sz	(1+NFS3_post_op_attr_sz+1)
#define NFS3_readlinkres_sz	(1+NFS3_post_op_attr_sz+1)
#define NFS3_readres_sz		(1+NFS3_post_op_attr_sz+3)
#define NFS3_writeres_sz	(1+NFS3_wcc_data_sz+4)
#define NFS3_createres_sz	(1+NFS3_fh_sz+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
#define NFS3_renameres_sz	(1+(2 * NFS3_wcc_data_sz))
#define NFS3_linkres_sz		(1+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
#define NFS3_readdirres_sz	(1+NFS3_post_op_attr_sz+2)
#define NFS3_fsstatres_sz	(1+NFS3_post_op_attr_sz+13)
#define NFS3_fsinfores_sz	(1+NFS3_post_op_attr_sz+12)
#define NFS3_pathconfres_sz	(1+NFS3_post_op_attr_sz+6)
#define NFS3_commitres_sz	(1+NFS3_wcc_data_sz+2)

#define ACL3_getaclargs_sz	(NFS3_fh_sz+1)
#define ACL3_setaclargs_sz	(NFS3_fh_sz+1+2*(2+5*3))
#define ACL3_getaclres_sz	(1+NFS3_post_op_attr_sz+1+2*(2+5*3))
#define ACL3_setaclres_sz	(1+NFS3_post_op_attr_sz)

/*
 * Map file type to S_IFMT bits
 */
static struct {
	unsigned int	mode;
	unsigned int	nfs2type;
} nfs_type2fmt[] = {
      { 0,		NFNON	},
      { S_IFREG,	NFREG	},
      { S_IFDIR,	NFDIR	},
      { S_IFBLK,	NFBLK	},
      { S_IFCHR,	NFCHR	},
      { S_IFLNK,	NFLNK	},
      { S_IFSOCK,	NFSOCK	},
      { S_IFIFO,	NFFIFO	},
      { 0,		NFBAD	}
};

/*
 * Common NFS XDR functions as inlines
 */
static inline u32 *
xdr_encode_fhandle(u32 *p, struct nfs_fh *fh)
{
	return xdr_encode_array(p, fh->data, fh->size);
}

static inline u32 *
xdr_decode_fhandle(u32 *p, struct nfs_fh *fh)
{
	if ((fh->size = ntohl(*p++)) <= NFS3_FHSIZE) {
		memcpy(fh->data, p, fh->size);
		return p + XDR_QUADLEN(fh->size);
	}
	return NULL;
}

/*
 * Encode/decode time.
 */
static inline u32 *
xdr_encode_time3(u32 *p, struct timespec *timep)
{
	*p++ = htonl(timep->tv_sec);
	*p++ = htonl(timep->tv_nsec);
	return p;
}

static inline u32 *
xdr_decode_time3(u32 *p, struct timespec *timep)
{
	timep->tv_sec = ntohl(*p++);
	timep->tv_nsec = ntohl(*p++);
	return p;
}

static u32 *
xdr_decode_fattr(u32 *p, struct nfs_fattr *fattr)
{
	unsigned int	type, major, minor;
	int		fmode;

	type = ntohl(*p++);
	if (type >= NF3BAD)
		type = NF3BAD;
	fmode = nfs_type2fmt[type].mode;
	fattr->type = nfs_type2fmt[type].nfs2type;
	fattr->mode = (ntohl(*p++) & ~S_IFMT) | fmode;
	fattr->nlink = ntohl(*p++);
	fattr->uid = ntohl(*p++);
	fattr->gid = ntohl(*p++);
	p = xdr_decode_hyper(p, &fattr->size);
	p = xdr_decode_hyper(p, &fattr->du.nfs3.used);

	/* Turn remote device info into Linux-specific dev_t */
	major = ntohl(*p++);
	minor = ntohl(*p++);
	fattr->rdev = MKDEV(major, minor);
	if (MAJOR(fattr->rdev) != major || MINOR(fattr->rdev) != minor)
		fattr->rdev = 0;

	p = xdr_decode_hyper(p, &fattr->fsid.major);
	fattr->fsid.minor = 0;
	p = xdr_decode_hyper(p, &fattr->fileid);
	p = xdr_decode_time3(p, &fattr->atime);
	p = xdr_decode_time3(p, &fattr->mtime);
	p = xdr_decode_time3(p, &fattr->ctime);

	/* Update the mode bits */
	fattr->valid |= (NFS_ATTR_FATTR | NFS_ATTR_FATTR_V3);
	return p;
}

static inline u32 *
xdr_encode_sattr(u32 *p, struct iattr *attr)
{
	if (attr->ia_valid & ATTR_MODE) {
		*p++ = xdr_one;
		*p++ = htonl(attr->ia_mode & S_IALLUGO);
	} else {
		*p++ = xdr_zero;
	}
	if (attr->ia_valid & ATTR_UID) {
		*p++ = xdr_one;
		*p++ = htonl(attr->ia_uid);
	} else {
		*p++ = xdr_zero;
	}
	if (attr->ia_valid & ATTR_GID) {
		*p++ = xdr_one;
		*p++ = htonl(attr->ia_gid);
	} else {
		*p++ = xdr_zero;
	}
	if (attr->ia_valid & ATTR_SIZE) {
		*p++ = xdr_one;
		p = xdr_encode_hyper(p, (__u64) attr->ia_size);
	} else {
		*p++ = xdr_zero;
	}
	if (attr->ia_valid & ATTR_ATIME_SET) {
		*p++ = xdr_two;
		p = xdr_encode_time3(p, &attr->ia_atime);
	} else if (attr->ia_valid & ATTR_ATIME) {
		*p++ = xdr_one;
	} else {
		*p++ = xdr_zero;
	}
	if (attr->ia_valid & ATTR_MTIME_SET) {
		*p++ = xdr_two;
		p = xdr_encode_time3(p, &attr->ia_mtime);
	} else if (attr->ia_valid & ATTR_MTIME) {
		*p++ = xdr_one;
	} else {
		*p++ = xdr_zero;
	}
	return p;
}

static inline u32 *
xdr_decode_wcc_attr(u32 *p, struct nfs_fattr *fattr)
{
	p = xdr_decode_hyper(p, &fattr->pre_size);
	p = xdr_decode_time3(p, &fattr->pre_mtime);
	p = xdr_decode_time3(p, &fattr->pre_ctime);
	fattr->valid |= NFS_ATTR_WCC;
	return p;
}

static inline u32 *
xdr_decode_post_op_attr(u32 *p, struct nfs_fattr *fattr)
{
	if (*p++)
		p = xdr_decode_fattr(p, fattr);
	return p;
}

static inline u32 *
xdr_decode_pre_op_attr(u32 *p, struct nfs_fattr *fattr)
{
	if (*p++)
		return xdr_decode_wcc_attr(p, fattr);
	return p;
}


static inline u32 *
xdr_decode_wcc_data(u32 *p, struct nfs_fattr *fattr)
{
	p = xdr_decode_pre_op_attr(p, fattr);
	return xdr_decode_post_op_attr(p, fattr);
}

/*
 * NFS encode functions
 */

/*
 * Encode file handle argument
 */
static int
nfs3_xdr_fhandle(struct rpc_rqst *req, u32 *p, struct nfs_fh *fh)
{
	p = xdr_encode_fhandle(p, fh);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

/*
 * Encode SETATTR arguments
 */
static int
nfs3_xdr_sattrargs(struct rpc_rqst *req, u32 *p, struct nfs3_sattrargs *args)
{
	p = xdr_encode_fhandle(p, args->fh);
	p = xdr_encode_sattr(p, args->sattr);
	*p++ = htonl(args->guard);
	if (args->guard)
		p = xdr_encode_time3(p, &args->guardtime);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

/*
 * Encode directory ops argument
 */
static int
nfs3_xdr_diropargs(struct rpc_rqst *req, u32 *p, struct nfs3_diropargs *args)
{
	p = xdr_encode_fhandle(p, args->fh);
	p = xdr_encode_array(p, args->name, args->len);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

/*
 * Encode access() argument
 */
static int
nfs3_xdr_accessargs(struct rpc_rqst *req, u32 *p, struct nfs3_accessargs *args)
{
	p = xdr_encode_fhandle(p, args->fh);
	*p++ = htonl(args->access);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

/*
 * Arguments to a READ call. Since we read data directly into the page
 * cache, we also set up the reply iovec here so that iov[1] points
 * exactly to the page we want to fetch.
 */
static int
nfs3_xdr_readargs(struct rpc_rqst *req, u32 *p, struct nfs_readargs *args)
{
	struct rpc_auth	*auth = req->rq_task->tk_auth;
	unsigned int replen;
	u32 count = args->count;

	p = xdr_encode_fhandle(p, args->fh);
	p = xdr_encode_hyper(p, args->offset);
	*p++ = htonl(count);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);

	/* Inline the page array */
	replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS3_readres_sz) << 2;
	xdr_inline_pages(&req->rq_rcv_buf, replen,
			 args->pages, args->pgbase, count);
	return 0;
}

/*
 * Write arguments. Splice the buffer to be written into the iovec.
 */
static int
nfs3_xdr_writeargs(struct rpc_rqst *req, u32 *p, struct nfs_writeargs *args)
{
	struct xdr_buf *sndbuf = &req->rq_snd_buf;
	u32 count = args->count;

	p = xdr_encode_fhandle(p, args->fh);
	p = xdr_encode_hyper(p, args->offset);
	*p++ = htonl(count);
	*p++ = htonl(args->stable);
	*p++ = htonl(count);
	sndbuf->len = xdr_adjust_iovec(sndbuf->head, p);

	/* Copy the page array */
	xdr_encode_pages(sndbuf, args->pages, args->pgbase, count);
	return 0;
}

/*
 * Encode CREATE arguments
 */
static int
nfs3_xdr_createargs(struct rpc_rqst *req, u32 *p, struct nfs3_createargs *args)
{
	p = xdr_encode_fhandle(p, args->fh);
	p = xdr_encode_array(p, args->name, args->len);

	*p++ = htonl(args->createmode);
	if (args->createmode == NFS3_CREATE_EXCLUSIVE) {
		*p++ = args->verifier[0];
		*p++ = args->verifier[1];
	} else
		p = xdr_encode_sattr(p, args->sattr);

	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

/*
 * Encode MKDIR arguments
 */
static int
nfs3_xdr_mkdirargs(struct rpc_rqst *req, u32 *p, struct nfs3_mkdirargs *args)
{
	p = xdr_encode_fhandle(p, args->fh);
	p = xdr_encode_array(p, args->name, args->len);
	p = xdr_encode_sattr(p, args->sattr);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

/*
 * Encode SYMLINK arguments
 */
static int
nfs3_xdr_symlinkargs(struct rpc_rqst *req, u32 *p, struct nfs3_symlinkargs *args)
{
	p = xdr_encode_fhandle(p, args->fromfh);
	p = xdr_encode_array(p, args->fromname, args->fromlen);
	p = xdr_encode_sattr(p, args->sattr);
	p = xdr_encode_array(p, args->topath, args->tolen);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

/*
 * Encode MKNOD arguments
 */
static int
nfs3_xdr_mknodargs(struct rpc_rqst *req, u32 *p, struct nfs3_mknodargs *args)
{
	p = xdr_encode_fhandle(p, args->fh);
	p = xdr_encode_array(p, args->name, args->len);
	*p++ = htonl(args->type);
	p = xdr_encode_sattr(p, args->sattr);
	if (args->type == NF3CHR || args->type == NF3BLK) {
		*p++ = htonl(MAJOR(args->rdev));
		*p++ = htonl(MINOR(args->rdev));
	}

	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

/*
 * Encode RENAME arguments
 */
static int
nfs3_xdr_renameargs(struct rpc_rqst *req, u32 *p, struct nfs3_renameargs *args)
{
	p = xdr_encode_fhandle(p, args->fromfh);
	p = xdr_encode_array(p, args->fromname, args->fromlen);
	p = xdr_encode_fhandle(p, args->tofh);
	p = xdr_encode_array(p, args->toname, args->tolen);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

/*
 * Encode LINK arguments
 */
static int
nfs3_xdr_linkargs(struct rpc_rqst *req, u32 *p, struct nfs3_linkargs *args)
{
	p = xdr_encode_fhandle(p, args->fromfh);
	p = xdr_encode_fhandle(p, args->tofh);
	p = xdr_encode_array(p, args->toname, args->tolen);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

/*
 * Encode arguments to readdir call
 */
static int
nfs3_xdr_readdirargs(struct rpc_rqst *req, u32 *p, struct nfs3_readdirargs *args)
{
	struct rpc_auth	*auth = req->rq_task->tk_auth;
	unsigned int replen;
	u32 count = args->count;

	p = xdr_encode_fhandle(p, args->fh);
	p = xdr_encode_hyper(p, args->cookie);
	*p++ = args->verf[0];
	*p++ = args->verf[1];
	if (args->plus) {
		/* readdirplus: need dircount + buffer size.
		 * We just make sure we make dircount big enough */
		*p++ = htonl(count >> 3);
	}
	*p++ = htonl(count);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);

	/* Inline the page array */
	replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS3_readdirres_sz) << 2;
	xdr_inline_pages(&req->rq_rcv_buf, replen, args->pages, 0, count);
	return 0;
}

/*
 * Decode the result of a readdir call.
 * We just check for syntactical correctness.
 */
static int
nfs3_xdr_readdirres(struct rpc_rqst *req, u32 *p, struct nfs3_readdirres *res)
{
	struct xdr_buf *rcvbuf = &req->rq_rcv_buf;
	struct kvec *iov = rcvbuf->head;
	struct page **page;
	int hdrlen, recvd;
	int status, nr;
	unsigned int len, pglen;
	u32 *entry, *end, *kaddr;

	status = ntohl(*p++);
	/* Decode post_op_attrs */
	p = xdr_decode_post_op_attr(p, res->dir_attr);
	if (status)
		return -nfs_stat_to_errno(status);
	/* Decode verifier cookie */
	if (res->verf) {
		res->verf[0] = *p++;
		res->verf[1] = *p++;
	} else {
		p += 2;
	}

	hdrlen = (u8 *) p - (u8 *) iov->iov_base;
	if (iov->iov_len < hdrlen) {
		printk(KERN_WARNING "NFS: READDIR reply header overflowed:"
				"length %d > %Zu\n", hdrlen, iov->iov_len);
		return -errno_NFSERR_IO;
	} else if (iov->iov_len != hdrlen) {
		dprintk("NFS: READDIR header is short. iovec will be shifted.\n");
		xdr_shift_buf(rcvbuf, iov->iov_len - hdrlen);
	}

	pglen = rcvbuf->page_len;
	recvd = rcvbuf->len - hdrlen;
	if (pglen > recvd)
		pglen = recvd;
	page = rcvbuf->pages;
	kaddr = p = (u32 *)kmap_atomic(*page, KM_USER0);
	end = (u32 *)((char *)p + pglen);
	entry = p;
	for (nr = 0; *p++; nr++) {
		if (p + 3 > end)
			goto short_pkt;
		p += 2;				/* inode # */
		len = ntohl(*p++);		/* string length */
		p += XDR_QUADLEN(len) + 2;	/* name + cookie */
		if (len > NFS3_MAXNAMLEN) {
			printk(KERN_WARNING "NFS: giant filename in readdir (len %x)!\n",
						len);
			goto err_unmap;
		}

		if (res->plus) {
			/* post_op_attr */
			if (p + 2 > end)
				goto short_pkt;
			if (*p++) {
				p += 21;
				if (p + 1 > end)
					goto short_pkt;
			}
			/* post_op_fh3 */
			if (*p++) {
				if (p + 1 > end)
					goto short_pkt;
				len = ntohl(*p++);
				if (len > NFS3_FHSIZE) {
					printk(KERN_WARNING "NFS: giant filehandle in "
						"readdir (len %x)!\n", len);
					goto err_unmap;
				}
				p += XDR_QUADLEN(len);
			}
		}

		if (p + 2 > end)
			goto short_pkt;
		entry = p;
	}
	if (!nr && (entry[0] != 0 || entry[1] == 0))
		goto short_pkt;
 out:
	kunmap_atomic(kaddr, KM_USER0);
	return nr;
 short_pkt:
	entry[0] = entry[1] = 0;
	/* truncate listing ? */
	if (!nr) {
		printk(KERN_NOTICE "NFS: readdir reply truncated!\n");
		entry[1] = 1;
	}
	goto out;
err_unmap:
	nr = -errno_NFSERR_IO;
	goto out;
}

u32 *
nfs3_decode_dirent(u32 *p, struct nfs_entry *entry, int plus)
{
	struct nfs_entry old = *entry;

	if (!*p++) {
		if (!*p)
			return ERR_PTR(-EAGAIN);
		entry->eof = 1;
		return ERR_PTR(-EBADCOOKIE);
	}

	p = xdr_decode_hyper(p, &entry->ino);
	entry->len  = ntohl(*p++);
	entry->name = (const char *) p;
	p += XDR_QUADLEN(entry->len);
	entry->prev_cookie = entry->cookie;
	p = xdr_decode_hyper(p, &entry->cookie);

	if (plus) {
		entry->fattr->valid = 0;
		p = xdr_decode_post_op_attr(p, entry->fattr);
		/* In fact, a post_op_fh3: */
		if (*p++) {
			p = xdr_decode_fhandle(p, entry->fh);
			/* Ugh -- server reply was truncated */
			if (p == NULL) {
				dprintk("NFS: FH truncated\n");
				*entry = old;
				return ERR_PTR(-EAGAIN);
			}
		} else
			memset((u8*)(entry->fh), 0, sizeof(*entry->fh));
	}

	entry->eof = !p[0] && p[1];
	return p;
}

/*
 * Encode COMMIT arguments
 */
static int
nfs3_xdr_commitargs(struct rpc_rqst *req, u32 *p, struct nfs_writeargs *args)
{
	p = xdr_encode_fhandle(p, args->fh);
	p = xdr_encode_hyper(p, args->offset);
	*p++ = htonl(args->count);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

#ifdef CONFIG_NFS_V3_ACL
/*
 * Encode GETACL arguments
 */
static int
nfs3_xdr_getaclargs(struct rpc_rqst *req, u32 *p,
		    struct nfs3_getaclargs *args)
{
	struct rpc_auth *auth = req->rq_task->tk_auth;
	unsigned int replen;

	p = xdr_encode_fhandle(p, args->fh);
	*p++ = htonl(args->mask);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);

	if (args->mask & (NFS_ACL | NFS_DFACL)) {
		/* Inline the page array */
		replen = (RPC_REPHDRSIZE + auth->au_rslack +
			  ACL3_getaclres_sz) << 2;
		xdr_inline_pages(&req->rq_rcv_buf, replen, args->pages, 0,
				 NFSACL_MAXPAGES << PAGE_SHIFT);
	}
	return 0;
}

/*
 * Encode SETACL arguments
 */
static int
nfs3_xdr_setaclargs(struct rpc_rqst *req, u32 *p,
                   struct nfs3_setaclargs *args)
{
	struct xdr_buf *buf = &req->rq_snd_buf;
	unsigned int base, len_in_head, len = nfsacl_size(
		(args->mask & NFS_ACL)   ? args->acl_access  : NULL,
		(args->mask & NFS_DFACL) ? args->acl_default : NULL);
	int count, err;

	p = xdr_encode_fhandle(p, NFS_FH(args->inode));
	*p++ = htonl(args->mask);
	base = (char *)p - (char *)buf->head->iov_base;
	/* put as much of the acls into head as possible. */
	len_in_head = min_t(unsigned int, buf->head->iov_len - base, len);
	len -= len_in_head;
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p + (len_in_head >> 2));

	for (count = 0; (count << PAGE_SHIFT) < len; count++) {
		args->pages[count] = alloc_page(GFP_KERNEL);
		if (!args->pages[count]) {
			while (count)
				__free_page(args->pages[--count]);
			return -ENOMEM;
		}
	}
	xdr_encode_pages(buf, args->pages, 0, len);

	err = nfsacl_encode(buf, base, args->inode,
			    (args->mask & NFS_ACL) ?
			    args->acl_access : NULL, 1, 0);
	if (err > 0)
		err = nfsacl_encode(buf, base + err, args->inode,
				    (args->mask & NFS_DFACL) ?
				    args->acl_default : NULL, 1,
				    NFS_ACL_DEFAULT);
	return (err > 0) ? 0 : err;
}
#endif  /* CONFIG_NFS_V3_ACL */

/*
 * NFS XDR decode functions
 */

/*
 * Decode attrstat reply.
 */
static int
nfs3_xdr_attrstat(struct rpc_rqst *req, u32 *p, struct nfs_fattr *fattr)
{
	int	status;

	if ((status = ntohl(*p++)))
		return -nfs_stat_to_errno(status);
	xdr_decode_fattr(p, fattr);
	return 0;
}

/*
 * Decode status+wcc_data reply
 * SATTR, REMOVE, RMDIR
 */
static int
nfs3_xdr_wccstat(struct rpc_rqst *req, u32 *p, struct nfs_fattr *fattr)
{
	int	status;

	if ((status = ntohl(*p++)))
		status = -nfs_stat_to_errno(status);
	xdr_decode_wcc_data(p, fattr);
	return status;
}

/*
 * Decode LOOKUP reply
 */
static int
nfs3_xdr_lookupres(struct rpc_rqst *req, u32 *p, struct nfs3_diropres *res)
{
	int	status;

	if ((status = ntohl(*p++))) {
		status = -nfs_stat_to_errno(status);
	} else {
		if (!(p = xdr_decode_fhandle(p, res->fh)))
			return -errno_NFSERR_IO;
		p = xdr_decode_post_op_attr(p, res->fattr);
	}
	xdr_decode_post_op_attr(p, res->dir_attr);
	return status;
}

/*
 * Decode ACCESS reply
 */
static int
nfs3_xdr_accessres(struct rpc_rqst *req, u32 *p, struct nfs3_accessres *res)
{
	int	status = ntohl(*p++);

	p = xdr_decode_post_op_attr(p, res->fattr);
	if (status)
		return -nfs_stat_to_errno(status);
	res->access = ntohl(*p++);
	return 0;
}

static int
nfs3_xdr_readlinkargs(struct rpc_rqst *req, u32 *p, struct nfs3_readlinkargs *args)
{
	struct rpc_auth *auth = req->rq_task->tk_auth;
	unsigned int replen;

	p = xdr_encode_fhandle(p, args->fh);
	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);

	/* Inline the page array */
	replen = (RPC_REPHDRSIZE + auth->au_rslack + NFS3_readlinkres_sz) << 2;
	xdr_inline_pages(&req->rq_rcv_buf, replen, args->pages, args->pgbase, args->pglen);
	return 0;
}

/*
 * Decode READLINK reply
 */
static int
nfs3_xdr_readlinkres(struct rpc_rqst *req, u32 *p, struct nfs_fattr *fattr)
{
	struct xdr_buf *rcvbuf = &req->rq_rcv_buf;
	struct kvec *iov = rcvbuf->head;
	int hdrlen, len, recvd;
	char	*kaddr;
	int	status;

	status = ntohl(*p++);
	p = xdr_decode_post_op_attr(p, fattr);

	if (status != 0)
		return -nfs_stat_to_errno(status);

	/* Convert length of symlink */
	len = ntohl(*p++);
	if (len >= rcvbuf->page_len || len <= 0) {
		dprintk(KERN_WARNING "nfs: server returned giant symlink!\n");
		return -ENAMETOOLONG;
	}

	hdrlen = (u8 *) p - (u8 *) iov->iov_base;
	if (iov->iov_len < hdrlen) {
		printk(KERN_WARNING "NFS: READLINK reply header overflowed:"
				"length %d > %Zu\n", hdrlen, iov->iov_len);
		return -errno_NFSERR_IO;
	} else if (iov->iov_len != hdrlen) {
		dprintk("NFS: READLINK header is short. iovec will be shifted.\n");
		xdr_shift_buf(rcvbuf, iov->iov_len - hdrlen);
	}
	recvd = req->rq_rcv_buf.len - hdrlen;
	if (recvd < len) {
		printk(KERN_WARNING "NFS: server cheating in readlink reply: "
				"count %u > recvd %u\n", len, recvd);
		return -EIO;
	}

	/* NULL terminate the string we got */
	kaddr = (char*)kmap_atomic(rcvbuf->pages[0], KM_USER0);
	kaddr[len+rcvbuf->page_base] = '\0';
	kunmap_atomic(kaddr, KM_USER0);
	return 0;
}

/*
 * Decode READ reply
 */
static int
nfs3_xdr_readres(struct rpc_rqst *req, u32 *p, struct nfs_readres *res)
{
	struct kvec *iov = req->rq_rcv_buf.head;
	int	status, count, ocount, recvd, hdrlen;

	status = ntohl(*p++);
	p = xdr_decode_post_op_attr(p, res->fattr);

	if (status != 0)
		return -nfs_stat_to_errno(status);

	/* Decode reply could and EOF flag. NFSv3 is somewhat redundant
	 * in that it puts the count both in the res struct and in the
	 * opaque data count. */
	count    = ntohl(*p++);
	res->eof = ntohl(*p++);
	ocount   = ntohl(*p++);

	if (ocount != count) {
		printk(KERN_WARNING "NFS: READ count doesn't match RPC opaque count.\n");
		return -errno_NFSERR_IO;
	}

	hdrlen = (u8 *) p - (u8 *) iov->iov_base;
	if (iov->iov_len < hdrlen) {
		printk(KERN_WARNING "NFS: READ reply header overflowed:"
				"length %d > %Zu\n", hdrlen, iov->iov_len);
       		return -errno_NFSERR_IO;
	} else if (iov->iov_len != hdrlen) {
		dprintk("NFS: READ header is short. iovec will be shifted.\n");
		xdr_shift_buf(&req->rq_rcv_buf, iov->iov_len - hdrlen);
	}

	recvd = req->rq_rcv_buf.len - hdrlen;
	if (count > recvd) {
		printk(KERN_WARNING "NFS: server cheating in read reply: "
			"count %d > recvd %d\n", count, recvd);
		count = recvd;
		res->eof = 0;
	}

	if (count < res->count)
		res->count = count;

	return count;
}

/*
 * Decode WRITE response
 */
static int
nfs3_xdr_writeres(struct rpc_rqst *req, u32 *p, struct nfs_writeres *res)
{
	int	status;

	status = ntohl(*p++);
	p = xdr_decode_wcc_data(p, res->fattr);

	if (status != 0)
		return -nfs_stat_to_errno(status);

	res->count = ntohl(*p++);
	res->verf->committed = (enum nfs3_stable_how)ntohl(*p++);
	res->verf->verifier[0] = *p++;
	res->verf->verifier[1] = *p++;

	return res->count;
}

/*
 * Decode a CREATE response
 */
static int
nfs3_xdr_createres(struct rpc_rqst *req, u32 *p, struct nfs3_diropres *res)
{
	int	status;

	status = ntohl(*p++);
	if (status == 0) {
		if (*p++) {
			if (!(p = xdr_decode_fhandle(p, res->fh)))
				return -errno_NFSERR_IO;
			p = xdr_decode_post_op_attr(p, res->fattr);
		} else {
			memset(res->fh, 0, sizeof(*res->fh));
			/* Do decode post_op_attr but set it to NULL */
			p = xdr_decode_post_op_attr(p, res->fattr);
			res->fattr->valid = 0;
		}
	} else {
		status = -nfs_stat_to_errno(status);
	}
	p = xdr_decode_wcc_data(p, res->dir_attr);
	return status;
}

/*
 * Decode RENAME reply
 */
static int
nfs3_xdr_renameres(struct rpc_rqst *req, u32 *p, struct nfs3_renameres *res)
{
	int	status;

	if ((status = ntohl(*p++)) != 0)
		status = -nfs_stat_to_errno(status);
	p = xdr_decode_wcc_data(p, res->fromattr);
	p = xdr_decode_wcc_data(p, res->toattr);
	return status;
}

/*
 * Decode LINK reply
 */
static int
nfs3_xdr_linkres(struct rpc_rqst *req, u32 *p, struct nfs3_linkres *res)
{
	int	status;

	if ((status = ntohl(*p++)) != 0)
		status = -nfs_stat_to_errno(status);
	p = xdr_decode_post_op_attr(p, res->fattr);
	p = xdr_decode_wcc_data(p, res->dir_attr);
	return status;
}

/*
 * Decode FSSTAT reply
 */
static int
nfs3_xdr_fsstatres(struct rpc_rqst *req, u32 *p, struct nfs_fsstat *res)
{
	int		status;

	status = ntohl(*p++);

	p = xdr_decode_post_op_attr(p, res->fattr);
	if (status != 0)
		return -nfs_stat_to_errno(status);

	p = xdr_decode_hyper(p, &res->tbytes);
	p = xdr_decode_hyper(p, &res->fbytes);
	p = xdr_decode_hyper(p, &res->abytes);
	p = xdr_decode_hyper(p, &res->tfiles);
	p = xdr_decode_hyper(p, &res->ffiles);
	p = xdr_decode_hyper(p, &res->afiles);

	/* ignore invarsec */
	return 0;
}

/*
 * Decode FSINFO reply
 */
static int
nfs3_xdr_fsinfores(struct rpc_rqst *req, u32 *p, struct nfs_fsinfo *res)
{
	int		status;

	status = ntohl(*p++);

	p = xdr_decode_post_op_attr(p, res->fattr);
	if (status != 0)
		return -nfs_stat_to_errno(status);

	res->rtmax  = ntohl(*p++);
	res->rtpref = ntohl(*p++);
	res->rtmult = ntohl(*p++);
	res->wtmax  = ntohl(*p++);
	res->wtpref = ntohl(*p++);
	res->wtmult = ntohl(*p++);
	res->dtpref = ntohl(*p++);
	p = xdr_decode_hyper(p, &res->maxfilesize);

	/* ignore time_delta and properties */
	res->lease_time = 0;
	return 0;
}

/*
 * Decode PATHCONF reply
 */
static int
nfs3_xdr_pathconfres(struct rpc_rqst *req, u32 *p, struct nfs_pathconf *res)
{
	int		status;

	status = ntohl(*p++);

	p = xdr_decode_post_op_attr(p, res->fattr);
	if (status != 0)
		return -nfs_stat_to_errno(status);
	res->max_link = ntohl(*p++);
	res->max_namelen = ntohl(*p++);

	/* ignore remaining fields */
	return 0;
}

/*
 * Decode COMMIT reply
 */
static int
nfs3_xdr_commitres(struct rpc_rqst *req, u32 *p, struct nfs_writeres *res)
{
	int		status;

	status = ntohl(*p++);
	p = xdr_decode_wcc_data(p, res->fattr);
	if (status != 0)
		return -nfs_stat_to_errno(status);

	res->verf->verifier[0] = *p++;
	res->verf->verifier[1] = *p++;
	return 0;
}

#ifdef CONFIG_NFS_V3_ACL
/*
 * Decode GETACL reply
 */
static int
nfs3_xdr_getaclres(struct rpc_rqst *req, u32 *p,
		   struct nfs3_getaclres *res)
{
	struct xdr_buf *buf = &req->rq_rcv_buf;
	int status = ntohl(*p++);
	struct posix_acl **acl;
	unsigned int *aclcnt;
	int err, base;

	if (status != 0)
		return -nfs_stat_to_errno(status);
	p = xdr_decode_post_op_attr(p, res->fattr);
	res->mask = ntohl(*p++);
	if (res->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT))
		return -EINVAL;
	base = (char *)p - (char *)req->rq_rcv_buf.head->iov_base;

	acl = (res->mask & NFS_ACL) ? &res->acl_access : NULL;
	aclcnt = (res->mask & NFS_ACLCNT) ? &res->acl_access_count : NULL;
	err = nfsacl_decode(buf, base, aclcnt, acl);

	acl = (res->mask & NFS_DFACL) ? &res->acl_default : NULL;
	aclcnt = (res->mask & NFS_DFACLCNT) ? &res->acl_default_count : NULL;
	if (err > 0)
		err = nfsacl_decode(buf, base + err, aclcnt, acl);
	return (err > 0) ? 0 : err;
}

/*
 * Decode setacl reply.
 */
static int
nfs3_xdr_setaclres(struct rpc_rqst *req, u32 *p, struct nfs_fattr *fattr)
{
	int status = ntohl(*p++);

	if (status)
		return -nfs_stat_to_errno(status);
	xdr_decode_post_op_attr(p, fattr);
	return 0;
}
#endif  /* CONFIG_NFS_V3_ACL */

#ifndef MAX
# define MAX(a, b)	(((a) > (b))? (a) : (b))
#endif

#define PROC(proc, argtype, restype, timer)				\
[NFS3PROC_##proc] = {							\
	.p_proc      = NFS3PROC_##proc,					\
	.p_encode    = (kxdrproc_t) nfs3_xdr_##argtype,			\
	.p_decode    = (kxdrproc_t) nfs3_xdr_##restype,			\
	.p_bufsiz    = MAX(NFS3_##argtype##_sz,NFS3_##restype##_sz) << 2,	\
	.p_timer     = timer,						\
	.p_statidx   = NFS3PROC_##proc,					\
	.p_name      = #proc,						\
	}

struct rpc_procinfo	nfs3_procedures[] = {
  PROC(GETATTR,		fhandle,	attrstat, 1),
  PROC(SETATTR, 	sattrargs,	wccstat, 0),
  PROC(LOOKUP,		diropargs,	lookupres, 2),
  PROC(ACCESS,		accessargs,	accessres, 1),
  PROC(READLINK,	readlinkargs,	readlinkres, 3),
  PROC(READ,		readargs,	readres, 3),
  PROC(WRITE,		writeargs,	writeres, 4),
  PROC(CREATE,		createargs,	createres, 0),
  PROC(MKDIR,		mkdirargs,	createres, 0),
  PROC(SYMLINK,		symlinkargs,	createres, 0),
  PROC(MKNOD,		mknodargs,	createres, 0),
  PROC(REMOVE,		diropargs,	wccstat, 0),
  PROC(RMDIR,		diropargs,	wccstat, 0),
  PROC(RENAME,		renameargs,	renameres, 0),
  PROC(LINK,		linkargs,	linkres, 0),
  PROC(READDIR,		readdirargs,	readdirres, 3),
  PROC(READDIRPLUS,	readdirargs,	readdirres, 3),
  PROC(FSSTAT,		fhandle,	fsstatres, 0),
  PROC(FSINFO,  	fhandle,	fsinfores, 0),
  PROC(PATHCONF,	fhandle,	pathconfres, 0),
  PROC(COMMIT,		commitargs,	commitres, 5),
};

struct rpc_version		nfs_version3 = {
	.number			= 3,
	.nrprocs		= ARRAY_SIZE(nfs3_procedures),
	.procs			= nfs3_procedures
};

#ifdef CONFIG_NFS_V3_ACL
static struct rpc_procinfo	nfs3_acl_procedures[] = {
	[ACLPROC3_GETACL] = {
		.p_proc = ACLPROC3_GETACL,
		.p_encode = (kxdrproc_t) nfs3_xdr_getaclargs,
		.p_decode = (kxdrproc_t) nfs3_xdr_getaclres,
		.p_bufsiz = MAX(ACL3_getaclargs_sz, ACL3_getaclres_sz) << 2,
		.p_timer = 1,
		.p_name = "GETACL",
	},
	[ACLPROC3_SETACL] = {
		.p_proc = ACLPROC3_SETACL,
		.p_encode = (kxdrproc_t) nfs3_xdr_setaclargs,
		.p_decode = (kxdrproc_t) nfs3_xdr_setaclres,
		.p_bufsiz = MAX(ACL3_setaclargs_sz, ACL3_setaclres_sz) << 2,
		.p_timer = 0,
		.p_name = "SETACL",
	},
};

struct rpc_version		nfsacl_version3 = {
	.number			= 3,
	.nrprocs		= sizeof(nfs3_acl_procedures)/
				  sizeof(nfs3_acl_procedures[0]),
	.procs			= nfs3_acl_procedures,
};
#endif  /* CONFIG_NFS_V3_ACL */