aboutsummaryrefslogtreecommitdiffstats
path: root/sys/fs/nfsclient/nfs_clcomsubs.c
blob: c16a3402946dc85a665d061ac23c699452239c76 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
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
/*-
 * Copyright (c) 1989, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * This code is derived from software contributed to Berkeley by
 * Rick Macklem at The University of Guelph.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. Redistributions in binary form must reproduce the above copyright
 *    notice, this list of conditions and the following disclaimer in the
 *    documentation and/or other materials provided with the distribution.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
 * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
 * SUCH DAMAGE.
 *
 */

#include <sys/cdefs.h>
__FBSDID("$FreeBSD$");

/*
 * These functions support the macros and help fiddle mbuf chains for
 * the nfs op functions. They do things like create the rpc header and
 * copy data between mbuf chains and uio lists.
 */
#ifndef APPLEKEXT
#include <fs/nfs/nfsport.h>

extern struct nfsstatsv1 nfsstatsv1;
extern struct nfsv4_opflag nfsv4_opflag[NFSV41_NOPS];
extern int ncl_mbuf_mlen;
extern enum vtype newnv2tov_type[8];
extern enum vtype nv34tov_type[8];
extern int	nfs_bigreply[NFSV41_NPROCS];
NFSCLSTATEMUTEX;
#endif	/* !APPLEKEXT */

static nfsuint64 nfs_nullcookie = {{ 0, 0 }};
static struct {
	int	op;
	int	opcnt;
	const u_char *tag;
	int	taglen;
} nfsv4_opmap[NFSV41_NPROCS] = {
	{ 0, 1, "Null", 4 },
	{ NFSV4OP_GETATTR, 1, "Getattr", 7, },
	{ NFSV4OP_SETATTR, 2, "Setattr", 7, },
	{ NFSV4OP_LOOKUP, 3, "Lookup", 6, },
	{ NFSV4OP_ACCESS, 2, "Access", 6, },
	{ NFSV4OP_READLINK, 2, "Readlink", 8, },
	{ NFSV4OP_READ, 1, "Read", 4, },
	{ NFSV4OP_WRITE, 2, "Write", 5, },
	{ NFSV4OP_OPEN, 5, "Open", 4, },
	{ NFSV4OP_CREATE, 5, "Create", 6, },
	{ NFSV4OP_CREATE, 1, "Create", 6, },
	{ NFSV4OP_CREATE, 3, "Create", 6, },
	{ NFSV4OP_REMOVE, 1, "Remove", 6, },
	{ NFSV4OP_REMOVE, 1, "Remove", 6, },
	{ NFSV4OP_SAVEFH, 5, "Rename", 6, },
	{ NFSV4OP_SAVEFH, 4, "Link", 4, },
	{ NFSV4OP_READDIR, 2, "Readdir", 7, },
	{ NFSV4OP_READDIR, 2, "Readdir", 7, },
	{ NFSV4OP_GETATTR, 1, "Getattr", 7, },
	{ NFSV4OP_GETATTR, 1, "Getattr", 7, },
	{ NFSV4OP_GETATTR, 1, "Getattr", 7, },
	{ NFSV4OP_COMMIT, 2, "Commit", 6, },
	{ NFSV4OP_LOOKUPP, 3, "Lookupp", 7, },
	{ NFSV4OP_SETCLIENTID, 1, "SetClientID", 11, },
	{ NFSV4OP_SETCLIENTIDCFRM, 1, "SetClientIDConfirm", 18, },
	{ NFSV4OP_LOCK, 1, "Lock", 4, },
	{ NFSV4OP_LOCKU, 1, "LockU", 5, },
	{ NFSV4OP_OPEN, 2, "Open", 4, },
	{ NFSV4OP_CLOSE, 1, "Close", 5, },
	{ NFSV4OP_OPENCONFIRM, 1, "Openconfirm", 11, },
	{ NFSV4OP_LOCKT, 1, "LockT", 5, },
	{ NFSV4OP_OPENDOWNGRADE, 1, "Opendowngrade", 13, },
	{ NFSV4OP_RENEW, 1, "Renew", 5, },
	{ NFSV4OP_PUTROOTFH, 1, "Dirpath", 7, },
	{ NFSV4OP_RELEASELCKOWN, 1, "Rellckown", 9, },
	{ NFSV4OP_DELEGRETURN, 1, "Delegret", 8, },
	{ NFSV4OP_DELEGRETURN, 3, "DelegRemove", 11, },
	{ NFSV4OP_DELEGRETURN, 7, "DelegRename1", 12, },
	{ NFSV4OP_DELEGRETURN, 9, "DelegRename2", 12, },
	{ NFSV4OP_GETATTR, 1, "Getacl", 6, },
	{ NFSV4OP_SETATTR, 1, "Setacl", 6, },
	{ NFSV4OP_EXCHANGEID, 1, "ExchangeID", 10, },
	{ NFSV4OP_CREATESESSION, 1, "CreateSession", 13, },
	{ NFSV4OP_DESTROYSESSION, 1, "DestroySession", 14, },
	{ NFSV4OP_DESTROYCLIENTID, 1, "DestroyClient", 13, },
	{ NFSV4OP_FREESTATEID, 1, "FreeStateID", 11, },
	{ NFSV4OP_LAYOUTGET, 1, "LayoutGet", 9, },
	{ NFSV4OP_GETDEVINFO, 1, "GetDeviceInfo", 13, },
	{ NFSV4OP_LAYOUTCOMMIT, 1, "LayoutCommit", 12, },
	{ NFSV4OP_LAYOUTRETURN, 1, "LayoutReturn", 12, },
	{ NFSV4OP_RECLAIMCOMPL, 1, "ReclaimComplete", 15, },
	{ NFSV4OP_WRITE, 1, "WriteDS", 7, },
	{ NFSV4OP_READ, 1, "ReadDS", 6, },
	{ NFSV4OP_COMMIT, 1, "CommitDS", 8, },
};

/*
 * NFS RPCS that have large request message size.
 */
static int nfs_bigrequest[NFSV41_NPROCS] = {
	0, 0, 0, 0, 0, 0, 0, 1, 0, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
	0, 0, 0, 0, 0, 0, 1, 0, 0
};

/*
 * Start building a request. Mostly just put the first file handle in
 * place.
 */
APPLESTATIC void
nfscl_reqstart(struct nfsrv_descript *nd, int procnum, struct nfsmount *nmp,
    u_int8_t *nfhp, int fhlen, u_int32_t **opcntpp, struct nfsclsession *sep)
{
	struct mbuf *mb;
	u_int32_t *tl;
	int opcnt;
	nfsattrbit_t attrbits;

	/*
	 * First, fill in some of the fields of nd.
	 */
	nd->nd_slotseq = NULL;
	if (NFSHASNFSV4(nmp)) {
		nd->nd_flag = ND_NFSV4 | ND_NFSCL;
		if (NFSHASNFSV4N(nmp))
			nd->nd_flag |= ND_NFSV41;
	} else if (NFSHASNFSV3(nmp))
		nd->nd_flag = ND_NFSV3 | ND_NFSCL;
	else
		nd->nd_flag = ND_NFSV2 | ND_NFSCL;
	nd->nd_procnum = procnum;
	nd->nd_repstat = 0;

	/*
	 * Get the first mbuf for the request.
	 */
	if (nfs_bigrequest[procnum])
		NFSMCLGET(mb, M_WAITOK);
	else
		NFSMGET(mb);
	mbuf_setlen(mb, 0);
	nd->nd_mreq = nd->nd_mb = mb;
	nd->nd_bpos = NFSMTOD(mb, caddr_t);
	
	/*
	 * And fill the first file handle into the request.
	 */
	if (nd->nd_flag & ND_NFSV4) {
		opcnt = nfsv4_opmap[procnum].opcnt +
		    nfsv4_opflag[nfsv4_opmap[procnum].op].needscfh;
		if ((nd->nd_flag & ND_NFSV41) != 0) {
			opcnt += nfsv4_opflag[nfsv4_opmap[procnum].op].needsseq;
			if (procnum == NFSPROC_RENEW)
				/*
				 * For the special case of Renew, just do a
				 * Sequence Op.
				 */
				opcnt = 1;
			else if (procnum == NFSPROC_WRITEDS ||
			    procnum == NFSPROC_COMMITDS)
				/*
				 * For the special case of a Writeor Commit to
				 * a DS, the opcnt == 3, for Sequence, PutFH,
				 * Write/Commit.
				 */
				opcnt = 3;
		}
		/*
		 * What should the tag really be?
		 */
		(void) nfsm_strtom(nd, nfsv4_opmap[procnum].tag,
			nfsv4_opmap[procnum].taglen);
		NFSM_BUILD(tl, u_int32_t *, 2 * NFSX_UNSIGNED);
		if ((nd->nd_flag & ND_NFSV41) != 0)
			*tl++ = txdr_unsigned(NFSV41_MINORVERSION);
		else
			*tl++ = txdr_unsigned(NFSV4_MINORVERSION);
		if (opcntpp != NULL)
			*opcntpp = tl;
		*tl = txdr_unsigned(opcnt);
		if ((nd->nd_flag & ND_NFSV41) != 0 &&
		    nfsv4_opflag[nfsv4_opmap[procnum].op].needsseq > 0) {
			if (nfsv4_opflag[nfsv4_opmap[procnum].op].loopbadsess >
			    0)
				nd->nd_flag |= ND_LOOPBADSESS;
			NFSM_BUILD(tl, u_int32_t *, NFSX_UNSIGNED);
			*tl = txdr_unsigned(NFSV4OP_SEQUENCE);
			if (sep == NULL) {
				sep = nfsmnt_mdssession(nmp);
				nfsv4_setsequence(nmp, nd, sep,
				    nfs_bigreply[procnum]);
			} else
				nfsv4_setsequence(nmp, nd, sep,
				    nfs_bigreply[procnum]);
		}
		if (nfsv4_opflag[nfsv4_opmap[procnum].op].needscfh > 0) {
			NFSM_BUILD(tl, u_int32_t *, NFSX_UNSIGNED);
			*tl = txdr_unsigned(NFSV4OP_PUTFH);
			(void) nfsm_fhtom(nd, nfhp, fhlen, 0);
			if (nfsv4_opflag[nfsv4_opmap[procnum].op].needscfh
			    == 2 && procnum != NFSPROC_WRITEDS &&
			    procnum != NFSPROC_COMMITDS) {
				NFSM_BUILD(tl, u_int32_t *, NFSX_UNSIGNED);
				*tl = txdr_unsigned(NFSV4OP_GETATTR);
				/*
				 * For Lookup Ops, we want all the directory
				 * attributes, so we can load the name cache.
				 */
				if (procnum == NFSPROC_LOOKUP ||
				    procnum == NFSPROC_LOOKUPP)
					NFSGETATTR_ATTRBIT(&attrbits);
				else {
					NFSWCCATTR_ATTRBIT(&attrbits);
					nd->nd_flag |= ND_V4WCCATTR;
				}
				(void) nfsrv_putattrbit(nd, &attrbits);
			}
		}
		if (procnum != NFSPROC_RENEW ||
		    (nd->nd_flag & ND_NFSV41) == 0) {
			NFSM_BUILD(tl, u_int32_t *, NFSX_UNSIGNED);
			*tl = txdr_unsigned(nfsv4_opmap[procnum].op);
		}
	} else {
		(void) nfsm_fhtom(nd, nfhp, fhlen, 0);
	}
	if (procnum < NFSV41_NPROCS)
		NFSINCRGLOBAL(nfsstatsv1.rpccnt[procnum]);
}

#ifndef APPLE
/*
 * copies a uio scatter/gather list to an mbuf chain.
 * NOTE: can ony handle iovcnt == 1
 */
APPLESTATIC void
nfsm_uiombuf(struct nfsrv_descript *nd, struct uio *uiop, int siz)
{
	char *uiocp;
	struct mbuf *mp, *mp2;
	int xfer, left, mlen;
	int uiosiz, clflg, rem;
	char *cp, *tcp;

	KASSERT(uiop->uio_iovcnt == 1, ("nfsm_uiotombuf: iovcnt != 1"));

	if (siz > ncl_mbuf_mlen)	/* or should it >= MCLBYTES ?? */
		clflg = 1;
	else
		clflg = 0;
	rem = NFSM_RNDUP(siz) - siz;
	mp = mp2 = nd->nd_mb;
	while (siz > 0) {
		left = uiop->uio_iov->iov_len;
		uiocp = uiop->uio_iov->iov_base;
		if (left > siz)
			left = siz;
		uiosiz = left;
		while (left > 0) {
			mlen = M_TRAILINGSPACE(mp);
			if (mlen == 0) {
				if (clflg)
					NFSMCLGET(mp, M_WAITOK);
				else
					NFSMGET(mp);
				mbuf_setlen(mp, 0);
				mbuf_setnext(mp2, mp);
				mp2 = mp;
				mlen = M_TRAILINGSPACE(mp);
			}
			xfer = (left > mlen) ? mlen : left;
#ifdef notdef
			/* Not Yet.. */
			if (uiop->uio_iov->iov_op != NULL)
				(*(uiop->uio_iov->iov_op))
				(uiocp, NFSMTOD(mp, caddr_t) + mbuf_len(mp),
				    xfer);
			else
#endif
			if (uiop->uio_segflg == UIO_SYSSPACE)
			    NFSBCOPY(uiocp, NFSMTOD(mp, caddr_t) + mbuf_len(mp),
				xfer);
			else
			    copyin(CAST_USER_ADDR_T(uiocp), NFSMTOD(mp, caddr_t)
				+ mbuf_len(mp), xfer);
			mbuf_setlen(mp, mbuf_len(mp) + xfer);
			left -= xfer;
			uiocp += xfer;
			uiop->uio_offset += xfer;
			uiop->uio_resid -= xfer;
		}
		tcp = (char *)uiop->uio_iov->iov_base;
		tcp += uiosiz;
		uiop->uio_iov->iov_base = (void *)tcp;
		uiop->uio_iov->iov_len -= uiosiz;
		siz -= uiosiz;
	}
	if (rem > 0) {
		if (rem > M_TRAILINGSPACE(mp)) {
			NFSMGET(mp);
			mbuf_setlen(mp, 0);
			mbuf_setnext(mp2, mp);
		}
		cp = NFSMTOD(mp, caddr_t) + mbuf_len(mp);
		for (left = 0; left < rem; left++)
			*cp++ = '\0';
		mbuf_setlen(mp, mbuf_len(mp) + rem);
		nd->nd_bpos = cp;
	} else
		nd->nd_bpos = NFSMTOD(mp, caddr_t) + mbuf_len(mp);
	nd->nd_mb = mp;
}
#endif	/* !APPLE */

/*
 * Load vnode attributes from the xdr file attributes.
 * Returns EBADRPC if they can't be parsed, 0 otherwise.
 */
APPLESTATIC int
nfsm_loadattr(struct nfsrv_descript *nd, struct nfsvattr *nap)
{
	struct nfs_fattr *fp;
	int error = 0;

	if (nd->nd_flag & ND_NFSV4) {
		error = nfsv4_loadattr(nd, NULL, nap, NULL, NULL, 0, NULL,
		    NULL, NULL, NULL, NULL, 0, NULL, NULL, NULL, NULL, NULL);
	} else if (nd->nd_flag & ND_NFSV3) {
		NFSM_DISSECT(fp, struct nfs_fattr *, NFSX_V3FATTR);
		nap->na_type = nfsv34tov_type(fp->fa_type);
		nap->na_mode = fxdr_unsigned(u_short, fp->fa_mode);
		nap->na_rdev = makedev(fxdr_unsigned(u_char, fp->fa3_rdev.specdata1),
			fxdr_unsigned(u_char, fp->fa3_rdev.specdata2));
		nap->na_nlink = fxdr_unsigned(u_short, fp->fa_nlink);
		nap->na_uid = fxdr_unsigned(uid_t, fp->fa_uid);
		nap->na_gid = fxdr_unsigned(gid_t, fp->fa_gid);
		nap->na_size = fxdr_hyper(&fp->fa3_size);
		nap->na_blocksize = NFS_FABLKSIZE;
		nap->na_bytes = fxdr_hyper(&fp->fa3_used);
		nap->na_fileid = fxdr_hyper(&fp->fa3_fileid);
		fxdr_nfsv3time(&fp->fa3_atime, &nap->na_atime);
		fxdr_nfsv3time(&fp->fa3_ctime, &nap->na_ctime);
		fxdr_nfsv3time(&fp->fa3_mtime, &nap->na_mtime);
		nap->na_flags = 0;
		nap->na_filerev = 0;
	} else {
		NFSM_DISSECT(fp, struct nfs_fattr *, NFSX_V2FATTR);
		nap->na_type = nfsv2tov_type(fp->fa_type);
		nap->na_mode = fxdr_unsigned(u_short, fp->fa_mode);
		if (nap->na_type == VNON || nap->na_type == VREG)
			nap->na_type = IFTOVT(nap->na_mode);
		nap->na_rdev = fxdr_unsigned(dev_t, fp->fa2_rdev);

		/*
		 * Really ugly NFSv2 kludge.
		 */
		if (nap->na_type == VCHR && nap->na_rdev == ((dev_t)-1))
			nap->na_type = VFIFO;
		nap->na_nlink = fxdr_unsigned(u_short, fp->fa_nlink);
		nap->na_uid = fxdr_unsigned(uid_t, fp->fa_uid);
		nap->na_gid = fxdr_unsigned(gid_t, fp->fa_gid);
		nap->na_size = fxdr_unsigned(u_int32_t, fp->fa2_size);
		nap->na_blocksize = fxdr_unsigned(int32_t, fp->fa2_blocksize);
		nap->na_bytes =
		    (u_quad_t)fxdr_unsigned(int32_t, fp->fa2_blocks) *
		    NFS_FABLKSIZE;
		nap->na_fileid = fxdr_unsigned(uint64_t, fp->fa2_fileid);
		fxdr_nfsv2time(&fp->fa2_atime, &nap->na_atime);
		fxdr_nfsv2time(&fp->fa2_mtime, &nap->na_mtime);
		nap->na_flags = 0;
		nap->na_ctime.tv_sec = fxdr_unsigned(u_int32_t,
		    fp->fa2_ctime.nfsv2_sec);
		nap->na_ctime.tv_nsec = 0;
		nap->na_gen = fxdr_unsigned(u_int32_t,fp->fa2_ctime.nfsv2_usec);
		nap->na_filerev = 0;
	}
nfsmout:
	return (error);
}

/*
 * This function finds the directory cookie that corresponds to the
 * logical byte offset given.
 */
APPLESTATIC nfsuint64 *
nfscl_getcookie(struct nfsnode *np, off_t off, int add)
{
	struct nfsdmap *dp, *dp2;
	int pos;

	pos = off / NFS_DIRBLKSIZ;
	if (pos == 0) {
		KASSERT(!add, ("nfs getcookie add at 0"));
		return (&nfs_nullcookie);
	}
	pos--;
	dp = LIST_FIRST(&np->n_cookies);
	if (!dp) {
		if (add) {
			MALLOC(dp, struct nfsdmap *, sizeof (struct nfsdmap),
				M_NFSDIROFF, M_WAITOK);
			dp->ndm_eocookie = 0;
			LIST_INSERT_HEAD(&np->n_cookies, dp, ndm_list);
		} else
			return (NULL);
	}
	while (pos >= NFSNUMCOOKIES) {
		pos -= NFSNUMCOOKIES;
		if (LIST_NEXT(dp, ndm_list) != NULL) {
			if (!add && dp->ndm_eocookie < NFSNUMCOOKIES &&
				pos >= dp->ndm_eocookie)
				return (NULL);
			dp = LIST_NEXT(dp, ndm_list);
		} else if (add) {
			MALLOC(dp2, struct nfsdmap *, sizeof (struct nfsdmap),
				M_NFSDIROFF, M_WAITOK);
			dp2->ndm_eocookie = 0;
			LIST_INSERT_AFTER(dp, dp2, ndm_list);
			dp = dp2;
		} else
			return (NULL);
	}
	if (pos >= dp->ndm_eocookie) {
		if (add)
			dp->ndm_eocookie = pos + 1;
		else
			return (NULL);
	}
	return (&dp->ndm_cookies[pos]);
}

/*
 * Gets a file handle out of an nfs reply sent to the client and returns
 * the file handle and the file's attributes.
 * For V4, it assumes that Getfh and Getattr Op's results are here.
 */
APPLESTATIC int
nfscl_mtofh(struct nfsrv_descript *nd, struct nfsfh **nfhpp,
    struct nfsvattr *nap, int *attrflagp)
{
	u_int32_t *tl;
	int error = 0, flag = 1;

	*nfhpp = NULL;
	*attrflagp = 0;
	/*
	 * First get the file handle and vnode.
	 */
	if (nd->nd_flag & ND_NFSV3) {
		NFSM_DISSECT(tl, u_int32_t *, NFSX_UNSIGNED);
		flag = fxdr_unsigned(int, *tl);
	} else if (nd->nd_flag & ND_NFSV4) {
		NFSM_DISSECT(tl, u_int32_t *, 2 * NFSX_UNSIGNED);
		/* If the GetFH failed, clear flag. */
		if (*++tl != 0) {
			nd->nd_flag |= ND_NOMOREDATA;
			flag = 0;
			error = ENXIO;	/* Return ENXIO so *nfhpp isn't used. */
		}
	}
	if (flag) {
		error = nfsm_getfh(nd, nfhpp);
		if (error)
			return (error);
	}

	/*
	 * Now, get the attributes.
	 */
	if (flag != 0 && (nd->nd_flag & ND_NFSV4) != 0) {
		NFSM_DISSECT(tl, u_int32_t *, 2 * NFSX_UNSIGNED);
		if (*++tl != 0) {
			nd->nd_flag |= ND_NOMOREDATA;
			flag = 0;
		}
	} else if (nd->nd_flag & ND_NFSV3) {
		NFSM_DISSECT(tl, u_int32_t *, NFSX_UNSIGNED);
		if (flag) {
			flag = fxdr_unsigned(int, *tl);
		} else if (fxdr_unsigned(int, *tl)) {
			error = nfsm_advance(nd, NFSX_V3FATTR, -1);
			if (error)
				return (error);
		}
	}
	if (flag) {
		error = nfsm_loadattr(nd, nap);
		if (!error)
			*attrflagp = 1;
	}
nfsmout:
	return (error);
}

/*
 * Put a state Id in the mbuf list.
 */
APPLESTATIC void
nfsm_stateidtom(struct nfsrv_descript *nd, nfsv4stateid_t *stateidp, int flag)
{
	nfsv4stateid_t *st;

	NFSM_BUILD(st, nfsv4stateid_t *, NFSX_STATEID);
	if (flag == NFSSTATEID_PUTALLZERO) {
		st->seqid = 0;
		st->other[0] = 0;
		st->other[1] = 0;
		st->other[2] = 0;
	} else if (flag == NFSSTATEID_PUTALLONE) {
		st->seqid = 0xffffffff;
		st->other[0] = 0xffffffff;
		st->other[1] = 0xffffffff;
		st->other[2] = 0xffffffff;
	} else if (flag == NFSSTATEID_PUTSEQIDZERO) {
		st->seqid = 0;
		st->other[0] = stateidp->other[0];
		st->other[1] = stateidp->other[1];
		st->other[2] = stateidp->other[2];
	} else {
		st->seqid = stateidp->seqid;
		st->other[0] = stateidp->other[0];
		st->other[1] = stateidp->other[1];
		st->other[2] = stateidp->other[2];
	}
}

/*
 * Initialize the owner/delegation sleep lock.
 */
APPLESTATIC void
nfscl_lockinit(struct nfsv4lock *lckp)
{

	lckp->nfslock_usecnt = 0;
	lckp->nfslock_lock = 0;
}

/*
 * Get an exclusive lock. (Not needed for OpenBSD4, since there is only one
 * thread for each posix process in the kernel.)
 */
APPLESTATIC void
nfscl_lockexcl(struct nfsv4lock *lckp, void *mutex)
{
	int igotlock;

	do {
		igotlock = nfsv4_lock(lckp, 1, NULL, mutex, NULL);
	} while (!igotlock);
}

/*
 * Release an exclusive lock.
 */
APPLESTATIC void
nfscl_lockunlock(struct nfsv4lock *lckp)
{

	nfsv4_unlock(lckp, 0);
}

/*
 * Called to derefernce a lock on a stateid (delegation or open owner).
 */
APPLESTATIC void
nfscl_lockderef(struct nfsv4lock *lckp)
{

	NFSLOCKCLSTATE();
	lckp->nfslock_usecnt--;
	if (lckp->nfslock_usecnt == 0 && (lckp->nfslock_lock & NFSV4LOCK_WANTED)) {
		lckp->nfslock_lock &= ~NFSV4LOCK_WANTED;
		wakeup((caddr_t)lckp);
	}
	NFSUNLOCKCLSTATE();
}