xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision baa7eb025ab14f3cba2e35c0a8648f9c9f01d24f)
1 /*
2  *  Server-side XDR for NFSv4
3  *
4  *  Copyright (c) 2002 The Regents of the University of Michigan.
5  *  All rights reserved.
6  *
7  *  Kendrick Smith <kmsmith@umich.edu>
8  *  Andy Adamson   <andros@umich.edu>
9  *
10  *  Redistribution and use in source and binary forms, with or without
11  *  modification, are permitted provided that the following conditions
12  *  are met:
13  *
14  *  1. Redistributions of source code must retain the above copyright
15  *     notice, this list of conditions and the following disclaimer.
16  *  2. Redistributions in binary form must reproduce the above copyright
17  *     notice, this list of conditions and the following disclaimer in the
18  *     documentation and/or other materials provided with the distribution.
19  *  3. Neither the name of the University nor the names of its
20  *     contributors may be used to endorse or promote products derived
21  *     from this software without specific prior written permission.
22  *
23  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
24  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
30  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  *
35  * TODO: Neil Brown made the following observation:  We currently
36  * initially reserve NFSD_BUFSIZE space on the transmit queue and
37  * never release any of that until the request is complete.
38  * It would be good to calculate a new maximum response size while
39  * decoding the COMPOUND, and call svc_reserve with this number
40  * at the end of nfs4svc_decode_compoundargs.
41  */
42 
43 #include <linux/slab.h>
44 #include <linux/namei.h>
45 #include <linux/statfs.h>
46 #include <linux/utsname.h>
47 #include <linux/nfsd_idmap.h>
48 #include <linux/nfs4_acl.h>
49 #include <linux/sunrpc/svcauth_gss.h>
50 
51 #include "xdr4.h"
52 #include "vfs.h"
53 
54 #define NFSDDBG_FACILITY		NFSDDBG_XDR
55 
56 /*
57  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
58  * directory in order to indicate to the client that a filesystem boundary is present
59  * We use a fixed fsid for a referral
60  */
61 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
62 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
63 
64 static __be32
65 check_filename(char *str, int len, __be32 err)
66 {
67 	int i;
68 
69 	if (len == 0)
70 		return nfserr_inval;
71 	if (isdotent(str, len))
72 		return err;
73 	for (i = 0; i < len; i++)
74 		if (str[i] == '/')
75 			return err;
76 	return 0;
77 }
78 
79 #define DECODE_HEAD				\
80 	__be32 *p;				\
81 	__be32 status
82 #define DECODE_TAIL				\
83 	status = 0;				\
84 out:						\
85 	return status;				\
86 xdr_error:					\
87 	dprintk("NFSD: xdr error (%s:%d)\n",	\
88 			__FILE__, __LINE__);	\
89 	status = nfserr_bad_xdr;		\
90 	goto out
91 
92 #define READ32(x)         (x) = ntohl(*p++)
93 #define READ64(x)         do {			\
94 	(x) = (u64)ntohl(*p++) << 32;		\
95 	(x) |= ntohl(*p++);			\
96 } while (0)
97 #define READTIME(x)       do {			\
98 	p++;					\
99 	(x) = ntohl(*p++);			\
100 	p++;					\
101 } while (0)
102 #define READMEM(x,nbytes) do {			\
103 	x = (char *)p;				\
104 	p += XDR_QUADLEN(nbytes);		\
105 } while (0)
106 #define SAVEMEM(x,nbytes) do {			\
107 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
108  		savemem(argp, p, nbytes) :	\
109  		(char *)p)) {			\
110 		dprintk("NFSD: xdr error (%s:%d)\n", \
111 				__FILE__, __LINE__); \
112 		goto xdr_error;			\
113 		}				\
114 	p += XDR_QUADLEN(nbytes);		\
115 } while (0)
116 #define COPYMEM(x,nbytes) do {			\
117 	memcpy((x), p, nbytes);			\
118 	p += XDR_QUADLEN(nbytes);		\
119 } while (0)
120 
121 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
122 #define READ_BUF(nbytes)  do {			\
123 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
124 		p = argp->p;			\
125 		argp->p += XDR_QUADLEN(nbytes);	\
126 	} else if (!(p = read_buf(argp, nbytes))) { \
127 		dprintk("NFSD: xdr error (%s:%d)\n", \
128 				__FILE__, __LINE__); \
129 		goto xdr_error;			\
130 	}					\
131 } while (0)
132 
133 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
134 {
135 	/* We want more bytes than seem to be available.
136 	 * Maybe we need a new page, maybe we have just run out
137 	 */
138 	unsigned int avail = (char *)argp->end - (char *)argp->p;
139 	__be32 *p;
140 	if (avail + argp->pagelen < nbytes)
141 		return NULL;
142 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
143 		return NULL;
144 	/* ok, we can do it with the current plus the next page */
145 	if (nbytes <= sizeof(argp->tmp))
146 		p = argp->tmp;
147 	else {
148 		kfree(argp->tmpp);
149 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
150 		if (!p)
151 			return NULL;
152 
153 	}
154 	/*
155 	 * The following memcpy is safe because read_buf is always
156 	 * called with nbytes > avail, and the two cases above both
157 	 * guarantee p points to at least nbytes bytes.
158 	 */
159 	memcpy(p, argp->p, avail);
160 	/* step to next page */
161 	argp->p = page_address(argp->pagelist[0]);
162 	argp->pagelist++;
163 	if (argp->pagelen < PAGE_SIZE) {
164 		argp->end = argp->p + (argp->pagelen>>2);
165 		argp->pagelen = 0;
166 	} else {
167 		argp->end = argp->p + (PAGE_SIZE>>2);
168 		argp->pagelen -= PAGE_SIZE;
169 	}
170 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
171 	argp->p += XDR_QUADLEN(nbytes - avail);
172 	return p;
173 }
174 
175 static int zero_clientid(clientid_t *clid)
176 {
177 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
178 }
179 
180 static int
181 defer_free(struct nfsd4_compoundargs *argp,
182 		void (*release)(const void *), void *p)
183 {
184 	struct tmpbuf *tb;
185 
186 	tb = kmalloc(sizeof(*tb), GFP_KERNEL);
187 	if (!tb)
188 		return -ENOMEM;
189 	tb->buf = p;
190 	tb->release = release;
191 	tb->next = argp->to_free;
192 	argp->to_free = tb;
193 	return 0;
194 }
195 
196 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
197 {
198 	if (p == argp->tmp) {
199 		p = kmalloc(nbytes, GFP_KERNEL);
200 		if (!p)
201 			return NULL;
202 		memcpy(p, argp->tmp, nbytes);
203 	} else {
204 		BUG_ON(p != argp->tmpp);
205 		argp->tmpp = NULL;
206 	}
207 	if (defer_free(argp, kfree, p)) {
208 		kfree(p);
209 		return NULL;
210 	} else
211 		return (char *)p;
212 }
213 
214 static __be32
215 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
216 {
217 	u32 bmlen;
218 	DECODE_HEAD;
219 
220 	bmval[0] = 0;
221 	bmval[1] = 0;
222 	bmval[2] = 0;
223 
224 	READ_BUF(4);
225 	READ32(bmlen);
226 	if (bmlen > 1000)
227 		goto xdr_error;
228 
229 	READ_BUF(bmlen << 2);
230 	if (bmlen > 0)
231 		READ32(bmval[0]);
232 	if (bmlen > 1)
233 		READ32(bmval[1]);
234 	if (bmlen > 2)
235 		READ32(bmval[2]);
236 
237 	DECODE_TAIL;
238 }
239 
240 static __be32
241 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
242 		   struct iattr *iattr, struct nfs4_acl **acl)
243 {
244 	int expected_len, len = 0;
245 	u32 dummy32;
246 	char *buf;
247 	int host_err;
248 
249 	DECODE_HEAD;
250 	iattr->ia_valid = 0;
251 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
252 		return status;
253 
254 	READ_BUF(4);
255 	READ32(expected_len);
256 
257 	if (bmval[0] & FATTR4_WORD0_SIZE) {
258 		READ_BUF(8);
259 		len += 8;
260 		READ64(iattr->ia_size);
261 		iattr->ia_valid |= ATTR_SIZE;
262 	}
263 	if (bmval[0] & FATTR4_WORD0_ACL) {
264 		int nace;
265 		struct nfs4_ace *ace;
266 
267 		READ_BUF(4); len += 4;
268 		READ32(nace);
269 
270 		if (nace > NFS4_ACL_MAX)
271 			return nfserr_resource;
272 
273 		*acl = nfs4_acl_new(nace);
274 		if (*acl == NULL) {
275 			host_err = -ENOMEM;
276 			goto out_nfserr;
277 		}
278 		defer_free(argp, kfree, *acl);
279 
280 		(*acl)->naces = nace;
281 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
282 			READ_BUF(16); len += 16;
283 			READ32(ace->type);
284 			READ32(ace->flag);
285 			READ32(ace->access_mask);
286 			READ32(dummy32);
287 			READ_BUF(dummy32);
288 			len += XDR_QUADLEN(dummy32) << 2;
289 			READMEM(buf, dummy32);
290 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
291 			host_err = 0;
292 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
293 				ace->who = 0;
294 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
295 				host_err = nfsd_map_name_to_gid(argp->rqstp,
296 						buf, dummy32, &ace->who);
297 			else
298 				host_err = nfsd_map_name_to_uid(argp->rqstp,
299 						buf, dummy32, &ace->who);
300 			if (host_err)
301 				goto out_nfserr;
302 		}
303 	} else
304 		*acl = NULL;
305 	if (bmval[1] & FATTR4_WORD1_MODE) {
306 		READ_BUF(4);
307 		len += 4;
308 		READ32(iattr->ia_mode);
309 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
310 		iattr->ia_valid |= ATTR_MODE;
311 	}
312 	if (bmval[1] & FATTR4_WORD1_OWNER) {
313 		READ_BUF(4);
314 		len += 4;
315 		READ32(dummy32);
316 		READ_BUF(dummy32);
317 		len += (XDR_QUADLEN(dummy32) << 2);
318 		READMEM(buf, dummy32);
319 		if ((host_err = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
320 			goto out_nfserr;
321 		iattr->ia_valid |= ATTR_UID;
322 	}
323 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
324 		READ_BUF(4);
325 		len += 4;
326 		READ32(dummy32);
327 		READ_BUF(dummy32);
328 		len += (XDR_QUADLEN(dummy32) << 2);
329 		READMEM(buf, dummy32);
330 		if ((host_err = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
331 			goto out_nfserr;
332 		iattr->ia_valid |= ATTR_GID;
333 	}
334 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
335 		READ_BUF(4);
336 		len += 4;
337 		READ32(dummy32);
338 		switch (dummy32) {
339 		case NFS4_SET_TO_CLIENT_TIME:
340 			/* We require the high 32 bits of 'seconds' to be 0, and we ignore
341 			   all 32 bits of 'nseconds'. */
342 			READ_BUF(12);
343 			len += 12;
344 			READ32(dummy32);
345 			if (dummy32)
346 				return nfserr_inval;
347 			READ32(iattr->ia_atime.tv_sec);
348 			READ32(iattr->ia_atime.tv_nsec);
349 			if (iattr->ia_atime.tv_nsec >= (u32)1000000000)
350 				return nfserr_inval;
351 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
352 			break;
353 		case NFS4_SET_TO_SERVER_TIME:
354 			iattr->ia_valid |= ATTR_ATIME;
355 			break;
356 		default:
357 			goto xdr_error;
358 		}
359 	}
360 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
361 		READ_BUF(4);
362 		len += 4;
363 		READ32(dummy32);
364 		switch (dummy32) {
365 		case NFS4_SET_TO_CLIENT_TIME:
366 			/* We require the high 32 bits of 'seconds' to be 0, and we ignore
367 			   all 32 bits of 'nseconds'. */
368 			READ_BUF(12);
369 			len += 12;
370 			READ32(dummy32);
371 			if (dummy32)
372 				return nfserr_inval;
373 			READ32(iattr->ia_mtime.tv_sec);
374 			READ32(iattr->ia_mtime.tv_nsec);
375 			if (iattr->ia_mtime.tv_nsec >= (u32)1000000000)
376 				return nfserr_inval;
377 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
378 			break;
379 		case NFS4_SET_TO_SERVER_TIME:
380 			iattr->ia_valid |= ATTR_MTIME;
381 			break;
382 		default:
383 			goto xdr_error;
384 		}
385 	}
386 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
387 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
388 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2)
389 		READ_BUF(expected_len - len);
390 	else if (len != expected_len)
391 		goto xdr_error;
392 
393 	DECODE_TAIL;
394 
395 out_nfserr:
396 	status = nfserrno(host_err);
397 	goto out;
398 }
399 
400 static __be32
401 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
402 {
403 	DECODE_HEAD;
404 
405 	READ_BUF(sizeof(stateid_t));
406 	READ32(sid->si_generation);
407 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
408 
409 	DECODE_TAIL;
410 }
411 
412 static __be32
413 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
414 {
415 	DECODE_HEAD;
416 
417 	READ_BUF(4);
418 	READ32(access->ac_req_access);
419 
420 	DECODE_TAIL;
421 }
422 
423 static __be32
424 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
425 {
426 	DECODE_HEAD;
427 
428 	close->cl_stateowner = NULL;
429 	READ_BUF(4);
430 	READ32(close->cl_seqid);
431 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
432 
433 	DECODE_TAIL;
434 }
435 
436 
437 static __be32
438 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
439 {
440 	DECODE_HEAD;
441 
442 	READ_BUF(12);
443 	READ64(commit->co_offset);
444 	READ32(commit->co_count);
445 
446 	DECODE_TAIL;
447 }
448 
449 static __be32
450 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
451 {
452 	DECODE_HEAD;
453 
454 	READ_BUF(4);
455 	READ32(create->cr_type);
456 	switch (create->cr_type) {
457 	case NF4LNK:
458 		READ_BUF(4);
459 		READ32(create->cr_linklen);
460 		READ_BUF(create->cr_linklen);
461 		SAVEMEM(create->cr_linkname, create->cr_linklen);
462 		break;
463 	case NF4BLK:
464 	case NF4CHR:
465 		READ_BUF(8);
466 		READ32(create->cr_specdata1);
467 		READ32(create->cr_specdata2);
468 		break;
469 	case NF4SOCK:
470 	case NF4FIFO:
471 	case NF4DIR:
472 	default:
473 		break;
474 	}
475 
476 	READ_BUF(4);
477 	READ32(create->cr_namelen);
478 	READ_BUF(create->cr_namelen);
479 	SAVEMEM(create->cr_name, create->cr_namelen);
480 	if ((status = check_filename(create->cr_name, create->cr_namelen, nfserr_inval)))
481 		return status;
482 
483 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
484 				    &create->cr_acl);
485 	if (status)
486 		goto out;
487 
488 	DECODE_TAIL;
489 }
490 
491 static inline __be32
492 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
493 {
494 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
495 }
496 
497 static inline __be32
498 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
499 {
500 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
501 }
502 
503 static __be32
504 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
505 {
506 	DECODE_HEAD;
507 
508 	READ_BUF(4);
509 	READ32(link->li_namelen);
510 	READ_BUF(link->li_namelen);
511 	SAVEMEM(link->li_name, link->li_namelen);
512 	if ((status = check_filename(link->li_name, link->li_namelen, nfserr_inval)))
513 		return status;
514 
515 	DECODE_TAIL;
516 }
517 
518 static __be32
519 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
520 {
521 	DECODE_HEAD;
522 
523 	lock->lk_replay_owner = NULL;
524 	/*
525 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
526 	*/
527 	READ_BUF(28);
528 	READ32(lock->lk_type);
529 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
530 		goto xdr_error;
531 	READ32(lock->lk_reclaim);
532 	READ64(lock->lk_offset);
533 	READ64(lock->lk_length);
534 	READ32(lock->lk_is_new);
535 
536 	if (lock->lk_is_new) {
537 		READ_BUF(4);
538 		READ32(lock->lk_new_open_seqid);
539 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
540 		if (status)
541 			return status;
542 		READ_BUF(8 + sizeof(clientid_t));
543 		READ32(lock->lk_new_lock_seqid);
544 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
545 		READ32(lock->lk_new_owner.len);
546 		READ_BUF(lock->lk_new_owner.len);
547 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
548 	} else {
549 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
550 		if (status)
551 			return status;
552 		READ_BUF(4);
553 		READ32(lock->lk_old_lock_seqid);
554 	}
555 
556 	DECODE_TAIL;
557 }
558 
559 static __be32
560 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
561 {
562 	DECODE_HEAD;
563 
564 	READ_BUF(32);
565 	READ32(lockt->lt_type);
566 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
567 		goto xdr_error;
568 	READ64(lockt->lt_offset);
569 	READ64(lockt->lt_length);
570 	COPYMEM(&lockt->lt_clientid, 8);
571 	READ32(lockt->lt_owner.len);
572 	READ_BUF(lockt->lt_owner.len);
573 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
574 
575 	if (argp->minorversion && !zero_clientid(&lockt->lt_clientid))
576 		return nfserr_inval;
577 	DECODE_TAIL;
578 }
579 
580 static __be32
581 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
582 {
583 	DECODE_HEAD;
584 
585 	locku->lu_stateowner = NULL;
586 	READ_BUF(8);
587 	READ32(locku->lu_type);
588 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
589 		goto xdr_error;
590 	READ32(locku->lu_seqid);
591 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
592 	if (status)
593 		return status;
594 	READ_BUF(16);
595 	READ64(locku->lu_offset);
596 	READ64(locku->lu_length);
597 
598 	DECODE_TAIL;
599 }
600 
601 static __be32
602 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
603 {
604 	DECODE_HEAD;
605 
606 	READ_BUF(4);
607 	READ32(lookup->lo_len);
608 	READ_BUF(lookup->lo_len);
609 	SAVEMEM(lookup->lo_name, lookup->lo_len);
610 	if ((status = check_filename(lookup->lo_name, lookup->lo_len, nfserr_noent)))
611 		return status;
612 
613 	DECODE_TAIL;
614 }
615 
616 static __be32
617 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
618 {
619 	DECODE_HEAD;
620 
621 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
622 	open->op_iattr.ia_valid = 0;
623 	open->op_stateowner = NULL;
624 
625 	/* seqid, share_access, share_deny, clientid, ownerlen */
626 	READ_BUF(16 + sizeof(clientid_t));
627 	READ32(open->op_seqid);
628 	READ32(open->op_share_access);
629 	READ32(open->op_share_deny);
630 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
631 	READ32(open->op_owner.len);
632 
633 	/* owner, open_flag */
634 	READ_BUF(open->op_owner.len + 4);
635 	SAVEMEM(open->op_owner.data, open->op_owner.len);
636 	READ32(open->op_create);
637 	switch (open->op_create) {
638 	case NFS4_OPEN_NOCREATE:
639 		break;
640 	case NFS4_OPEN_CREATE:
641 		READ_BUF(4);
642 		READ32(open->op_createmode);
643 		switch (open->op_createmode) {
644 		case NFS4_CREATE_UNCHECKED:
645 		case NFS4_CREATE_GUARDED:
646 			status = nfsd4_decode_fattr(argp, open->op_bmval,
647 				&open->op_iattr, &open->op_acl);
648 			if (status)
649 				goto out;
650 			break;
651 		case NFS4_CREATE_EXCLUSIVE:
652 			READ_BUF(8);
653 			COPYMEM(open->op_verf.data, 8);
654 			break;
655 		case NFS4_CREATE_EXCLUSIVE4_1:
656 			if (argp->minorversion < 1)
657 				goto xdr_error;
658 			READ_BUF(8);
659 			COPYMEM(open->op_verf.data, 8);
660 			status = nfsd4_decode_fattr(argp, open->op_bmval,
661 				&open->op_iattr, &open->op_acl);
662 			if (status)
663 				goto out;
664 			break;
665 		default:
666 			goto xdr_error;
667 		}
668 		break;
669 	default:
670 		goto xdr_error;
671 	}
672 
673 	/* open_claim */
674 	READ_BUF(4);
675 	READ32(open->op_claim_type);
676 	switch (open->op_claim_type) {
677 	case NFS4_OPEN_CLAIM_NULL:
678 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
679 		READ_BUF(4);
680 		READ32(open->op_fname.len);
681 		READ_BUF(open->op_fname.len);
682 		SAVEMEM(open->op_fname.data, open->op_fname.len);
683 		if ((status = check_filename(open->op_fname.data, open->op_fname.len, nfserr_inval)))
684 			return status;
685 		break;
686 	case NFS4_OPEN_CLAIM_PREVIOUS:
687 		READ_BUF(4);
688 		READ32(open->op_delegate_type);
689 		break;
690 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
691 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
692 		if (status)
693 			return status;
694 		READ_BUF(4);
695 		READ32(open->op_fname.len);
696 		READ_BUF(open->op_fname.len);
697 		SAVEMEM(open->op_fname.data, open->op_fname.len);
698 		if ((status = check_filename(open->op_fname.data, open->op_fname.len, nfserr_inval)))
699 			return status;
700 		break;
701 	default:
702 		goto xdr_error;
703 	}
704 
705 	DECODE_TAIL;
706 }
707 
708 static __be32
709 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
710 {
711 	DECODE_HEAD;
712 
713 	open_conf->oc_stateowner = NULL;
714 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
715 	if (status)
716 		return status;
717 	READ_BUF(4);
718 	READ32(open_conf->oc_seqid);
719 
720 	DECODE_TAIL;
721 }
722 
723 static __be32
724 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
725 {
726 	DECODE_HEAD;
727 
728 	open_down->od_stateowner = NULL;
729 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
730 	if (status)
731 		return status;
732 	READ_BUF(12);
733 	READ32(open_down->od_seqid);
734 	READ32(open_down->od_share_access);
735 	READ32(open_down->od_share_deny);
736 
737 	DECODE_TAIL;
738 }
739 
740 static __be32
741 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
742 {
743 	DECODE_HEAD;
744 
745 	READ_BUF(4);
746 	READ32(putfh->pf_fhlen);
747 	if (putfh->pf_fhlen > NFS4_FHSIZE)
748 		goto xdr_error;
749 	READ_BUF(putfh->pf_fhlen);
750 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
751 
752 	DECODE_TAIL;
753 }
754 
755 static __be32
756 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
757 {
758 	DECODE_HEAD;
759 
760 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
761 	if (status)
762 		return status;
763 	READ_BUF(12);
764 	READ64(read->rd_offset);
765 	READ32(read->rd_length);
766 
767 	DECODE_TAIL;
768 }
769 
770 static __be32
771 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
772 {
773 	DECODE_HEAD;
774 
775 	READ_BUF(24);
776 	READ64(readdir->rd_cookie);
777 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
778 	READ32(readdir->rd_dircount);    /* just in case you needed a useless field... */
779 	READ32(readdir->rd_maxcount);
780 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
781 		goto out;
782 
783 	DECODE_TAIL;
784 }
785 
786 static __be32
787 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
788 {
789 	DECODE_HEAD;
790 
791 	READ_BUF(4);
792 	READ32(remove->rm_namelen);
793 	READ_BUF(remove->rm_namelen);
794 	SAVEMEM(remove->rm_name, remove->rm_namelen);
795 	if ((status = check_filename(remove->rm_name, remove->rm_namelen, nfserr_noent)))
796 		return status;
797 
798 	DECODE_TAIL;
799 }
800 
801 static __be32
802 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
803 {
804 	DECODE_HEAD;
805 
806 	READ_BUF(4);
807 	READ32(rename->rn_snamelen);
808 	READ_BUF(rename->rn_snamelen + 4);
809 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
810 	READ32(rename->rn_tnamelen);
811 	READ_BUF(rename->rn_tnamelen);
812 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
813 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen, nfserr_noent)))
814 		return status;
815 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen, nfserr_inval)))
816 		return status;
817 
818 	DECODE_TAIL;
819 }
820 
821 static __be32
822 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
823 {
824 	DECODE_HEAD;
825 
826 	READ_BUF(sizeof(clientid_t));
827 	COPYMEM(clientid, sizeof(clientid_t));
828 
829 	DECODE_TAIL;
830 }
831 
832 static __be32
833 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
834 		     struct nfsd4_secinfo *secinfo)
835 {
836 	DECODE_HEAD;
837 
838 	READ_BUF(4);
839 	READ32(secinfo->si_namelen);
840 	READ_BUF(secinfo->si_namelen);
841 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
842 	status = check_filename(secinfo->si_name, secinfo->si_namelen,
843 								nfserr_noent);
844 	if (status)
845 		return status;
846 	DECODE_TAIL;
847 }
848 
849 static __be32
850 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
851 {
852 	__be32 status;
853 
854 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
855 	if (status)
856 		return status;
857 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
858 				  &setattr->sa_acl);
859 }
860 
861 static __be32
862 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
863 {
864 	DECODE_HEAD;
865 
866 	READ_BUF(12);
867 	COPYMEM(setclientid->se_verf.data, 8);
868 	READ32(setclientid->se_namelen);
869 
870 	READ_BUF(setclientid->se_namelen + 8);
871 	SAVEMEM(setclientid->se_name, setclientid->se_namelen);
872 	READ32(setclientid->se_callback_prog);
873 	READ32(setclientid->se_callback_netid_len);
874 
875 	READ_BUF(setclientid->se_callback_netid_len + 4);
876 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
877 	READ32(setclientid->se_callback_addr_len);
878 
879 	READ_BUF(setclientid->se_callback_addr_len + 4);
880 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
881 	READ32(setclientid->se_callback_ident);
882 
883 	DECODE_TAIL;
884 }
885 
886 static __be32
887 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
888 {
889 	DECODE_HEAD;
890 
891 	READ_BUF(8 + sizeof(nfs4_verifier));
892 	COPYMEM(&scd_c->sc_clientid, 8);
893 	COPYMEM(&scd_c->sc_confirm, sizeof(nfs4_verifier));
894 
895 	DECODE_TAIL;
896 }
897 
898 /* Also used for NVERIFY */
899 static __be32
900 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
901 {
902 #if 0
903 	struct nfsd4_compoundargs save = {
904 		.p = argp->p,
905 		.end = argp->end,
906 		.rqstp = argp->rqstp,
907 	};
908 	u32             ve_bmval[2];
909 	struct iattr    ve_iattr;           /* request */
910 	struct nfs4_acl *ve_acl;            /* request */
911 #endif
912 	DECODE_HEAD;
913 
914 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
915 		goto out;
916 
917 	/* For convenience's sake, we compare raw xdr'd attributes in
918 	 * nfsd4_proc_verify; however we still decode here just to return
919 	 * correct error in case of bad xdr. */
920 #if 0
921 	status = nfsd4_decode_fattr(ve_bmval, &ve_iattr, &ve_acl);
922 	if (status == nfserr_inval) {
923 		status = nfserrno(status);
924 		goto out;
925 	}
926 #endif
927 	READ_BUF(4);
928 	READ32(verify->ve_attrlen);
929 	READ_BUF(verify->ve_attrlen);
930 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
931 
932 	DECODE_TAIL;
933 }
934 
935 static __be32
936 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
937 {
938 	int avail;
939 	int v;
940 	int len;
941 	DECODE_HEAD;
942 
943 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
944 	if (status)
945 		return status;
946 	READ_BUF(16);
947 	READ64(write->wr_offset);
948 	READ32(write->wr_stable_how);
949 	if (write->wr_stable_how > 2)
950 		goto xdr_error;
951 	READ32(write->wr_buflen);
952 
953 	/* Sorry .. no magic macros for this.. *
954 	 * READ_BUF(write->wr_buflen);
955 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
956 	 */
957 	avail = (char*)argp->end - (char*)argp->p;
958 	if (avail + argp->pagelen < write->wr_buflen) {
959 		dprintk("NFSD: xdr error (%s:%d)\n",
960 				__FILE__, __LINE__);
961 		goto xdr_error;
962 	}
963 	argp->rqstp->rq_vec[0].iov_base = p;
964 	argp->rqstp->rq_vec[0].iov_len = avail;
965 	v = 0;
966 	len = write->wr_buflen;
967 	while (len > argp->rqstp->rq_vec[v].iov_len) {
968 		len -= argp->rqstp->rq_vec[v].iov_len;
969 		v++;
970 		argp->rqstp->rq_vec[v].iov_base = page_address(argp->pagelist[0]);
971 		argp->pagelist++;
972 		if (argp->pagelen >= PAGE_SIZE) {
973 			argp->rqstp->rq_vec[v].iov_len = PAGE_SIZE;
974 			argp->pagelen -= PAGE_SIZE;
975 		} else {
976 			argp->rqstp->rq_vec[v].iov_len = argp->pagelen;
977 			argp->pagelen -= len;
978 		}
979 	}
980 	argp->end = (__be32*) (argp->rqstp->rq_vec[v].iov_base + argp->rqstp->rq_vec[v].iov_len);
981 	argp->p = (__be32*)  (argp->rqstp->rq_vec[v].iov_base + (XDR_QUADLEN(len) << 2));
982 	argp->rqstp->rq_vec[v].iov_len = len;
983 	write->wr_vlen = v+1;
984 
985 	DECODE_TAIL;
986 }
987 
988 static __be32
989 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
990 {
991 	DECODE_HEAD;
992 
993 	READ_BUF(12);
994 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
995 	READ32(rlockowner->rl_owner.len);
996 	READ_BUF(rlockowner->rl_owner.len);
997 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
998 
999 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1000 		return nfserr_inval;
1001 	DECODE_TAIL;
1002 }
1003 
1004 static __be32
1005 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1006 			 struct nfsd4_exchange_id *exid)
1007 {
1008 	int dummy;
1009 	DECODE_HEAD;
1010 
1011 	READ_BUF(NFS4_VERIFIER_SIZE);
1012 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1013 
1014 	READ_BUF(4);
1015 	READ32(exid->clname.len);
1016 
1017 	READ_BUF(exid->clname.len);
1018 	SAVEMEM(exid->clname.data, exid->clname.len);
1019 
1020 	READ_BUF(4);
1021 	READ32(exid->flags);
1022 
1023 	/* Ignore state_protect4_a */
1024 	READ_BUF(4);
1025 	READ32(exid->spa_how);
1026 	switch (exid->spa_how) {
1027 	case SP4_NONE:
1028 		break;
1029 	case SP4_MACH_CRED:
1030 		/* spo_must_enforce */
1031 		READ_BUF(4);
1032 		READ32(dummy);
1033 		READ_BUF(dummy * 4);
1034 		p += dummy;
1035 
1036 		/* spo_must_allow */
1037 		READ_BUF(4);
1038 		READ32(dummy);
1039 		READ_BUF(dummy * 4);
1040 		p += dummy;
1041 		break;
1042 	case SP4_SSV:
1043 		/* ssp_ops */
1044 		READ_BUF(4);
1045 		READ32(dummy);
1046 		READ_BUF(dummy * 4);
1047 		p += dummy;
1048 
1049 		READ_BUF(4);
1050 		READ32(dummy);
1051 		READ_BUF(dummy * 4);
1052 		p += dummy;
1053 
1054 		/* ssp_hash_algs<> */
1055 		READ_BUF(4);
1056 		READ32(dummy);
1057 		READ_BUF(dummy);
1058 		p += XDR_QUADLEN(dummy);
1059 
1060 		/* ssp_encr_algs<> */
1061 		READ_BUF(4);
1062 		READ32(dummy);
1063 		READ_BUF(dummy);
1064 		p += XDR_QUADLEN(dummy);
1065 
1066 		/* ssp_window and ssp_num_gss_handles */
1067 		READ_BUF(8);
1068 		READ32(dummy);
1069 		READ32(dummy);
1070 		break;
1071 	default:
1072 		goto xdr_error;
1073 	}
1074 
1075 	/* Ignore Implementation ID */
1076 	READ_BUF(4);    /* nfs_impl_id4 array length */
1077 	READ32(dummy);
1078 
1079 	if (dummy > 1)
1080 		goto xdr_error;
1081 
1082 	if (dummy == 1) {
1083 		/* nii_domain */
1084 		READ_BUF(4);
1085 		READ32(dummy);
1086 		READ_BUF(dummy);
1087 		p += XDR_QUADLEN(dummy);
1088 
1089 		/* nii_name */
1090 		READ_BUF(4);
1091 		READ32(dummy);
1092 		READ_BUF(dummy);
1093 		p += XDR_QUADLEN(dummy);
1094 
1095 		/* nii_date */
1096 		READ_BUF(12);
1097 		p += 3;
1098 	}
1099 	DECODE_TAIL;
1100 }
1101 
1102 static __be32
1103 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1104 			    struct nfsd4_create_session *sess)
1105 {
1106 	DECODE_HEAD;
1107 
1108 	u32 dummy;
1109 	char *machine_name;
1110 	int i;
1111 	int nr_secflavs;
1112 
1113 	READ_BUF(16);
1114 	COPYMEM(&sess->clientid, 8);
1115 	READ32(sess->seqid);
1116 	READ32(sess->flags);
1117 
1118 	/* Fore channel attrs */
1119 	READ_BUF(28);
1120 	READ32(dummy); /* headerpadsz is always 0 */
1121 	READ32(sess->fore_channel.maxreq_sz);
1122 	READ32(sess->fore_channel.maxresp_sz);
1123 	READ32(sess->fore_channel.maxresp_cached);
1124 	READ32(sess->fore_channel.maxops);
1125 	READ32(sess->fore_channel.maxreqs);
1126 	READ32(sess->fore_channel.nr_rdma_attrs);
1127 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1128 		READ_BUF(4);
1129 		READ32(sess->fore_channel.rdma_attrs);
1130 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1131 		dprintk("Too many fore channel attr bitmaps!\n");
1132 		goto xdr_error;
1133 	}
1134 
1135 	/* Back channel attrs */
1136 	READ_BUF(28);
1137 	READ32(dummy); /* headerpadsz is always 0 */
1138 	READ32(sess->back_channel.maxreq_sz);
1139 	READ32(sess->back_channel.maxresp_sz);
1140 	READ32(sess->back_channel.maxresp_cached);
1141 	READ32(sess->back_channel.maxops);
1142 	READ32(sess->back_channel.maxreqs);
1143 	READ32(sess->back_channel.nr_rdma_attrs);
1144 	if (sess->back_channel.nr_rdma_attrs == 1) {
1145 		READ_BUF(4);
1146 		READ32(sess->back_channel.rdma_attrs);
1147 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1148 		dprintk("Too many back channel attr bitmaps!\n");
1149 		goto xdr_error;
1150 	}
1151 
1152 	READ_BUF(8);
1153 	READ32(sess->callback_prog);
1154 
1155 	/* callback_sec_params4 */
1156 	READ32(nr_secflavs);
1157 	for (i = 0; i < nr_secflavs; ++i) {
1158 		READ_BUF(4);
1159 		READ32(dummy);
1160 		switch (dummy) {
1161 		case RPC_AUTH_NULL:
1162 			/* Nothing to read */
1163 			break;
1164 		case RPC_AUTH_UNIX:
1165 			READ_BUF(8);
1166 			/* stamp */
1167 			READ32(dummy);
1168 
1169 			/* machine name */
1170 			READ32(dummy);
1171 			READ_BUF(dummy);
1172 			SAVEMEM(machine_name, dummy);
1173 
1174 			/* uid, gid */
1175 			READ_BUF(8);
1176 			READ32(sess->uid);
1177 			READ32(sess->gid);
1178 
1179 			/* more gids */
1180 			READ_BUF(4);
1181 			READ32(dummy);
1182 			READ_BUF(dummy * 4);
1183 			for (i = 0; i < dummy; ++i)
1184 				READ32(dummy);
1185 			break;
1186 		case RPC_AUTH_GSS:
1187 			dprintk("RPC_AUTH_GSS callback secflavor "
1188 				"not supported!\n");
1189 			READ_BUF(8);
1190 			/* gcbp_service */
1191 			READ32(dummy);
1192 			/* gcbp_handle_from_server */
1193 			READ32(dummy);
1194 			READ_BUF(dummy);
1195 			p += XDR_QUADLEN(dummy);
1196 			/* gcbp_handle_from_client */
1197 			READ_BUF(4);
1198 			READ32(dummy);
1199 			READ_BUF(dummy);
1200 			p += XDR_QUADLEN(dummy);
1201 			break;
1202 		default:
1203 			dprintk("Illegal callback secflavor\n");
1204 			return nfserr_inval;
1205 		}
1206 	}
1207 	DECODE_TAIL;
1208 }
1209 
1210 static __be32
1211 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1212 			     struct nfsd4_destroy_session *destroy_session)
1213 {
1214 	DECODE_HEAD;
1215 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1216 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1217 
1218 	DECODE_TAIL;
1219 }
1220 
1221 static __be32
1222 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1223 		      struct nfsd4_sequence *seq)
1224 {
1225 	DECODE_HEAD;
1226 
1227 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1228 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1229 	READ32(seq->seqid);
1230 	READ32(seq->slotid);
1231 	READ32(seq->maxslots);
1232 	READ32(seq->cachethis);
1233 
1234 	DECODE_TAIL;
1235 }
1236 
1237 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1238 {
1239 	DECODE_HEAD;
1240 
1241 	READ_BUF(4);
1242 	READ32(rc->rca_one_fs);
1243 
1244 	DECODE_TAIL;
1245 }
1246 
1247 static __be32
1248 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1249 {
1250 	return nfs_ok;
1251 }
1252 
1253 static __be32
1254 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1255 {
1256 	return nfserr_notsupp;
1257 }
1258 
1259 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1260 
1261 static nfsd4_dec nfsd4_dec_ops[] = {
1262 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1263 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1264 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1265 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1266 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1267 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1268 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1269 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1270 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1271 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1272 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1273 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1274 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1275 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1276 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1277 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1278 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1279 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1280 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1281 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1282 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_noop,
1283 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1284 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1285 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1286 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1287 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1288 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1289 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1290 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1291 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1292 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1293 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1294 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1295 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1296 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1297 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1298 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1299 };
1300 
1301 static nfsd4_dec nfsd41_dec_ops[] = {
1302 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1303 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1304 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1305 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1306 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1307 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1308 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1309 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1310 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1311 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1312 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1313 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1314 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1315 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1316 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1317 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1318 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1319 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_notsupp,
1320 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1321 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1322 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_notsupp,
1323 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1324 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1325 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1326 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1327 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1328 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1329 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_notsupp,
1330 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1331 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1332 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1333 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1334 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_notsupp,
1335 	[OP_SETCLIENTID_CONFIRM]= (nfsd4_dec)nfsd4_decode_notsupp,
1336 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1337 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1338 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_notsupp,
1339 
1340 	/* new operations for NFSv4.1 */
1341 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_notsupp,
1342 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_notsupp,
1343 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1344 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1345 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1346 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_notsupp,
1347 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1348 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1349 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1350 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1351 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1352 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1353 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_notsupp,
1354 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1355 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1356 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_notsupp,
1357 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1358 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_notsupp,
1359 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1360 };
1361 
1362 struct nfsd4_minorversion_ops {
1363 	nfsd4_dec *decoders;
1364 	int nops;
1365 };
1366 
1367 static struct nfsd4_minorversion_ops nfsd4_minorversion[] = {
1368 	[0] = { nfsd4_dec_ops, ARRAY_SIZE(nfsd4_dec_ops) },
1369 	[1] = { nfsd41_dec_ops, ARRAY_SIZE(nfsd41_dec_ops) },
1370 };
1371 
1372 static __be32
1373 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1374 {
1375 	DECODE_HEAD;
1376 	struct nfsd4_op *op;
1377 	struct nfsd4_minorversion_ops *ops;
1378 	int i;
1379 
1380 	/*
1381 	 * XXX: According to spec, we should check the tag
1382 	 * for UTF-8 compliance.  I'm postponing this for
1383 	 * now because it seems that some clients do use
1384 	 * binary tags.
1385 	 */
1386 	READ_BUF(4);
1387 	READ32(argp->taglen);
1388 	READ_BUF(argp->taglen + 8);
1389 	SAVEMEM(argp->tag, argp->taglen);
1390 	READ32(argp->minorversion);
1391 	READ32(argp->opcnt);
1392 
1393 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1394 		goto xdr_error;
1395 	if (argp->opcnt > 100)
1396 		goto xdr_error;
1397 
1398 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1399 		argp->ops = kmalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1400 		if (!argp->ops) {
1401 			argp->ops = argp->iops;
1402 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1403 			goto xdr_error;
1404 		}
1405 	}
1406 
1407 	if (argp->minorversion >= ARRAY_SIZE(nfsd4_minorversion))
1408 		argp->opcnt = 0;
1409 
1410 	ops = &nfsd4_minorversion[argp->minorversion];
1411 	for (i = 0; i < argp->opcnt; i++) {
1412 		op = &argp->ops[i];
1413 		op->replay = NULL;
1414 
1415 		/*
1416 		 * We can't use READ_BUF() here because we need to handle
1417 		 * a missing opcode as an OP_WRITE + 1. So we need to check
1418 		 * to see if we're truly at the end of our buffer or if there
1419 		 * is another page we need to flip to.
1420 		 */
1421 
1422 		if (argp->p == argp->end) {
1423 			if (argp->pagelen < 4) {
1424 				/* There isn't an opcode still on the wire */
1425 				op->opnum = OP_WRITE + 1;
1426 				op->status = nfserr_bad_xdr;
1427 				argp->opcnt = i+1;
1428 				break;
1429 			}
1430 
1431 			/*
1432 			 * False alarm. We just hit a page boundary, but there
1433 			 * is still data available.  Move pointer across page
1434 			 * boundary.  *snip from READ_BUF*
1435 			 */
1436 			argp->p = page_address(argp->pagelist[0]);
1437 			argp->pagelist++;
1438 			if (argp->pagelen < PAGE_SIZE) {
1439 				argp->end = argp->p + (argp->pagelen>>2);
1440 				argp->pagelen = 0;
1441 			} else {
1442 				argp->end = argp->p + (PAGE_SIZE>>2);
1443 				argp->pagelen -= PAGE_SIZE;
1444 			}
1445 		}
1446 		op->opnum = ntohl(*argp->p++);
1447 
1448 		if (op->opnum >= FIRST_NFS4_OP && op->opnum <= LAST_NFS4_OP)
1449 			op->status = ops->decoders[op->opnum](argp, &op->u);
1450 		else {
1451 			op->opnum = OP_ILLEGAL;
1452 			op->status = nfserr_op_illegal;
1453 		}
1454 
1455 		if (op->status) {
1456 			argp->opcnt = i+1;
1457 			break;
1458 		}
1459 	}
1460 
1461 	DECODE_TAIL;
1462 }
1463 
1464 #define WRITE32(n)               *p++ = htonl(n)
1465 #define WRITE64(n)               do {				\
1466 	*p++ = htonl((u32)((n) >> 32));				\
1467 	*p++ = htonl((u32)(n));					\
1468 } while (0)
1469 #define WRITEMEM(ptr,nbytes)     do { if (nbytes > 0) {		\
1470 	*(p + XDR_QUADLEN(nbytes) -1) = 0;                      \
1471 	memcpy(p, ptr, nbytes);					\
1472 	p += XDR_QUADLEN(nbytes);				\
1473 }} while (0)
1474 
1475 static void write32(__be32 **p, u32 n)
1476 {
1477 	*(*p)++ = n;
1478 }
1479 
1480 static void write64(__be32 **p, u64 n)
1481 {
1482 	write32(p, (u32)(n >> 32));
1483 	write32(p, (u32)n);
1484 }
1485 
1486 static void write_change(__be32 **p, struct kstat *stat, struct inode *inode)
1487 {
1488 	if (IS_I_VERSION(inode)) {
1489 		write64(p, inode->i_version);
1490 	} else {
1491 		write32(p, stat->ctime.tv_sec);
1492 		write32(p, stat->ctime.tv_nsec);
1493 	}
1494 }
1495 
1496 static void write_cinfo(__be32 **p, struct nfsd4_change_info *c)
1497 {
1498 	write32(p, c->atomic);
1499 	if (c->change_supported) {
1500 		write64(p, c->before_change);
1501 		write64(p, c->after_change);
1502 	} else {
1503 		write32(p, c->before_ctime_sec);
1504 		write32(p, c->before_ctime_nsec);
1505 		write32(p, c->after_ctime_sec);
1506 		write32(p, c->after_ctime_nsec);
1507 	}
1508 }
1509 
1510 #define RESERVE_SPACE(nbytes)	do {				\
1511 	p = resp->p;						\
1512 	BUG_ON(p + XDR_QUADLEN(nbytes) > resp->end);		\
1513 } while (0)
1514 #define ADJUST_ARGS()		resp->p = p
1515 
1516 /*
1517  * Header routine to setup seqid operation replay cache
1518  */
1519 #define ENCODE_SEQID_OP_HEAD					\
1520 	__be32 *save;						\
1521 								\
1522 	save = resp->p;
1523 
1524 /*
1525  * Routine for encoding the result of a "seqid-mutating" NFSv4 operation.  This
1526  * is where sequence id's are incremented, and the replay cache is filled.
1527  * Note that we increment sequence id's here, at the last moment, so we're sure
1528  * we know whether the error to be returned is a sequence id mutating error.
1529  */
1530 
1531 #define ENCODE_SEQID_OP_TAIL(stateowner) do {			\
1532 	if (seqid_mutating_err(nfserr) && stateowner) { 	\
1533 		stateowner->so_seqid++;				\
1534 		stateowner->so_replay.rp_status = nfserr;   	\
1535 		stateowner->so_replay.rp_buflen = 		\
1536 			  (((char *)(resp)->p - (char *)save)); \
1537 		memcpy(stateowner->so_replay.rp_buf, save,      \
1538  			stateowner->so_replay.rp_buflen); 	\
1539 	} } while (0);
1540 
1541 /* Encode as an array of strings the string given with components
1542  * separated @sep.
1543  */
1544 static __be32 nfsd4_encode_components(char sep, char *components,
1545 				   __be32 **pp, int *buflen)
1546 {
1547 	__be32 *p = *pp;
1548 	__be32 *countp = p;
1549 	int strlen, count=0;
1550 	char *str, *end;
1551 
1552 	dprintk("nfsd4_encode_components(%s)\n", components);
1553 	if ((*buflen -= 4) < 0)
1554 		return nfserr_resource;
1555 	WRITE32(0); /* We will fill this in with @count later */
1556 	end = str = components;
1557 	while (*end) {
1558 		for (; *end && (*end != sep); end++)
1559 			; /* Point to end of component */
1560 		strlen = end - str;
1561 		if (strlen) {
1562 			if ((*buflen -= ((XDR_QUADLEN(strlen) << 2) + 4)) < 0)
1563 				return nfserr_resource;
1564 			WRITE32(strlen);
1565 			WRITEMEM(str, strlen);
1566 			count++;
1567 		}
1568 		else
1569 			end++;
1570 		str = end;
1571 	}
1572 	*pp = p;
1573 	p = countp;
1574 	WRITE32(count);
1575 	return 0;
1576 }
1577 
1578 /*
1579  * encode a location element of a fs_locations structure
1580  */
1581 static __be32 nfsd4_encode_fs_location4(struct nfsd4_fs_location *location,
1582 				    __be32 **pp, int *buflen)
1583 {
1584 	__be32 status;
1585 	__be32 *p = *pp;
1586 
1587 	status = nfsd4_encode_components(':', location->hosts, &p, buflen);
1588 	if (status)
1589 		return status;
1590 	status = nfsd4_encode_components('/', location->path, &p, buflen);
1591 	if (status)
1592 		return status;
1593 	*pp = p;
1594 	return 0;
1595 }
1596 
1597 /*
1598  * Return the path to an export point in the pseudo filesystem namespace
1599  * Returned string is safe to use as long as the caller holds a reference
1600  * to @exp.
1601  */
1602 static char *nfsd4_path(struct svc_rqst *rqstp, struct svc_export *exp, __be32 *stat)
1603 {
1604 	struct svc_fh tmp_fh;
1605 	char *path = NULL, *rootpath;
1606 	size_t rootlen;
1607 
1608 	fh_init(&tmp_fh, NFS4_FHSIZE);
1609 	*stat = exp_pseudoroot(rqstp, &tmp_fh);
1610 	if (*stat)
1611 		return NULL;
1612 	rootpath = tmp_fh.fh_export->ex_pathname;
1613 
1614 	path = exp->ex_pathname;
1615 
1616 	rootlen = strlen(rootpath);
1617 	if (strncmp(path, rootpath, rootlen)) {
1618 		dprintk("nfsd: fs_locations failed;"
1619 			"%s is not contained in %s\n", path, rootpath);
1620 		*stat = nfserr_notsupp;
1621 		path = NULL;
1622 		goto out;
1623 	}
1624 	path += rootlen;
1625 out:
1626 	fh_put(&tmp_fh);
1627 	return path;
1628 }
1629 
1630 /*
1631  *  encode a fs_locations structure
1632  */
1633 static __be32 nfsd4_encode_fs_locations(struct svc_rqst *rqstp,
1634 				     struct svc_export *exp,
1635 				     __be32 **pp, int *buflen)
1636 {
1637 	__be32 status;
1638 	int i;
1639 	__be32 *p = *pp;
1640 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
1641 	char *root = nfsd4_path(rqstp, exp, &status);
1642 
1643 	if (status)
1644 		return status;
1645 	status = nfsd4_encode_components('/', root, &p, buflen);
1646 	if (status)
1647 		return status;
1648 	if ((*buflen -= 4) < 0)
1649 		return nfserr_resource;
1650 	WRITE32(fslocs->locations_count);
1651 	for (i=0; i<fslocs->locations_count; i++) {
1652 		status = nfsd4_encode_fs_location4(&fslocs->locations[i],
1653 						   &p, buflen);
1654 		if (status)
1655 			return status;
1656 	}
1657 	*pp = p;
1658 	return 0;
1659 }
1660 
1661 static u32 nfs4_ftypes[16] = {
1662         NF4BAD,  NF4FIFO, NF4CHR, NF4BAD,
1663         NF4DIR,  NF4BAD,  NF4BLK, NF4BAD,
1664         NF4REG,  NF4BAD,  NF4LNK, NF4BAD,
1665         NF4SOCK, NF4BAD,  NF4LNK, NF4BAD,
1666 };
1667 
1668 static __be32
1669 nfsd4_encode_name(struct svc_rqst *rqstp, int whotype, uid_t id, int group,
1670 			__be32 **p, int *buflen)
1671 {
1672 	int status;
1673 
1674 	if (*buflen < (XDR_QUADLEN(IDMAP_NAMESZ) << 2) + 4)
1675 		return nfserr_resource;
1676 	if (whotype != NFS4_ACL_WHO_NAMED)
1677 		status = nfs4_acl_write_who(whotype, (u8 *)(*p + 1));
1678 	else if (group)
1679 		status = nfsd_map_gid_to_name(rqstp, id, (u8 *)(*p + 1));
1680 	else
1681 		status = nfsd_map_uid_to_name(rqstp, id, (u8 *)(*p + 1));
1682 	if (status < 0)
1683 		return nfserrno(status);
1684 	*p = xdr_encode_opaque(*p, NULL, status);
1685 	*buflen -= (XDR_QUADLEN(status) << 2) + 4;
1686 	BUG_ON(*buflen < 0);
1687 	return 0;
1688 }
1689 
1690 static inline __be32
1691 nfsd4_encode_user(struct svc_rqst *rqstp, uid_t uid, __be32 **p, int *buflen)
1692 {
1693 	return nfsd4_encode_name(rqstp, NFS4_ACL_WHO_NAMED, uid, 0, p, buflen);
1694 }
1695 
1696 static inline __be32
1697 nfsd4_encode_group(struct svc_rqst *rqstp, uid_t gid, __be32 **p, int *buflen)
1698 {
1699 	return nfsd4_encode_name(rqstp, NFS4_ACL_WHO_NAMED, gid, 1, p, buflen);
1700 }
1701 
1702 static inline __be32
1703 nfsd4_encode_aclname(struct svc_rqst *rqstp, int whotype, uid_t id, int group,
1704 		__be32 **p, int *buflen)
1705 {
1706 	return nfsd4_encode_name(rqstp, whotype, id, group, p, buflen);
1707 }
1708 
1709 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
1710 			      FATTR4_WORD0_RDATTR_ERROR)
1711 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
1712 
1713 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *rdattr_err)
1714 {
1715 	/* As per referral draft:  */
1716 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
1717 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
1718 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
1719 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
1720 			*rdattr_err = NFSERR_MOVED;
1721 		else
1722 			return nfserr_moved;
1723 	}
1724 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
1725 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
1726 	return 0;
1727 }
1728 
1729 /*
1730  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
1731  * ourselves.
1732  *
1733  * @countp is the buffer size in _words_; upon successful return this becomes
1734  * replaced with the number of words written.
1735  */
1736 __be32
1737 nfsd4_encode_fattr(struct svc_fh *fhp, struct svc_export *exp,
1738 		struct dentry *dentry, __be32 *buffer, int *countp, u32 *bmval,
1739 		struct svc_rqst *rqstp, int ignore_crossmnt)
1740 {
1741 	u32 bmval0 = bmval[0];
1742 	u32 bmval1 = bmval[1];
1743 	u32 bmval2 = bmval[2];
1744 	struct kstat stat;
1745 	struct svc_fh tempfh;
1746 	struct kstatfs statfs;
1747 	int buflen = *countp << 2;
1748 	__be32 *attrlenp;
1749 	u32 dummy;
1750 	u64 dummy64;
1751 	u32 rdattr_err = 0;
1752 	__be32 *p = buffer;
1753 	__be32 status;
1754 	int err;
1755 	int aclsupport = 0;
1756 	struct nfs4_acl *acl = NULL;
1757 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
1758 	u32 minorversion = resp->cstate.minorversion;
1759 	struct path path = {
1760 		.mnt	= exp->ex_path.mnt,
1761 		.dentry	= dentry,
1762 	};
1763 
1764 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
1765 	BUG_ON(bmval0 & ~nfsd_suppattrs0(minorversion));
1766 	BUG_ON(bmval1 & ~nfsd_suppattrs1(minorversion));
1767 	BUG_ON(bmval2 & ~nfsd_suppattrs2(minorversion));
1768 
1769 	if (exp->ex_fslocs.migrated) {
1770 		BUG_ON(bmval[2]);
1771 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &rdattr_err);
1772 		if (status)
1773 			goto out;
1774 	}
1775 
1776 	err = vfs_getattr(exp->ex_path.mnt, dentry, &stat);
1777 	if (err)
1778 		goto out_nfserr;
1779 	if ((bmval0 & (FATTR4_WORD0_FILES_FREE | FATTR4_WORD0_FILES_TOTAL |
1780 			FATTR4_WORD0_MAXNAME)) ||
1781 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
1782 		       FATTR4_WORD1_SPACE_TOTAL))) {
1783 		err = vfs_statfs(&path, &statfs);
1784 		if (err)
1785 			goto out_nfserr;
1786 	}
1787 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
1788 		fh_init(&tempfh, NFS4_FHSIZE);
1789 		status = fh_compose(&tempfh, exp, dentry, NULL);
1790 		if (status)
1791 			goto out;
1792 		fhp = &tempfh;
1793 	}
1794 	if (bmval0 & (FATTR4_WORD0_ACL | FATTR4_WORD0_ACLSUPPORT
1795 			| FATTR4_WORD0_SUPPORTED_ATTRS)) {
1796 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
1797 		aclsupport = (err == 0);
1798 		if (bmval0 & FATTR4_WORD0_ACL) {
1799 			if (err == -EOPNOTSUPP)
1800 				bmval0 &= ~FATTR4_WORD0_ACL;
1801 			else if (err == -EINVAL) {
1802 				status = nfserr_attrnotsupp;
1803 				goto out;
1804 			} else if (err != 0)
1805 				goto out_nfserr;
1806 		}
1807 	}
1808 
1809 	if (bmval2) {
1810 		if ((buflen -= 16) < 0)
1811 			goto out_resource;
1812 		WRITE32(3);
1813 		WRITE32(bmval0);
1814 		WRITE32(bmval1);
1815 		WRITE32(bmval2);
1816 	} else if (bmval1) {
1817 		if ((buflen -= 12) < 0)
1818 			goto out_resource;
1819 		WRITE32(2);
1820 		WRITE32(bmval0);
1821 		WRITE32(bmval1);
1822 	} else {
1823 		if ((buflen -= 8) < 0)
1824 			goto out_resource;
1825 		WRITE32(1);
1826 		WRITE32(bmval0);
1827 	}
1828 	attrlenp = p++;                /* to be backfilled later */
1829 
1830 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
1831 		u32 word0 = nfsd_suppattrs0(minorversion);
1832 		u32 word1 = nfsd_suppattrs1(minorversion);
1833 		u32 word2 = nfsd_suppattrs2(minorversion);
1834 
1835 		if (!aclsupport)
1836 			word0 &= ~FATTR4_WORD0_ACL;
1837 		if (!word2) {
1838 			if ((buflen -= 12) < 0)
1839 				goto out_resource;
1840 			WRITE32(2);
1841 			WRITE32(word0);
1842 			WRITE32(word1);
1843 		} else {
1844 			if ((buflen -= 16) < 0)
1845 				goto out_resource;
1846 			WRITE32(3);
1847 			WRITE32(word0);
1848 			WRITE32(word1);
1849 			WRITE32(word2);
1850 		}
1851 	}
1852 	if (bmval0 & FATTR4_WORD0_TYPE) {
1853 		if ((buflen -= 4) < 0)
1854 			goto out_resource;
1855 		dummy = nfs4_ftypes[(stat.mode & S_IFMT) >> 12];
1856 		if (dummy == NF4BAD)
1857 			goto out_serverfault;
1858 		WRITE32(dummy);
1859 	}
1860 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
1861 		if ((buflen -= 4) < 0)
1862 			goto out_resource;
1863 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
1864 			WRITE32(NFS4_FH_PERSISTENT);
1865 		else
1866 			WRITE32(NFS4_FH_PERSISTENT|NFS4_FH_VOL_RENAME);
1867 	}
1868 	if (bmval0 & FATTR4_WORD0_CHANGE) {
1869 		if ((buflen -= 8) < 0)
1870 			goto out_resource;
1871 		write_change(&p, &stat, dentry->d_inode);
1872 	}
1873 	if (bmval0 & FATTR4_WORD0_SIZE) {
1874 		if ((buflen -= 8) < 0)
1875 			goto out_resource;
1876 		WRITE64(stat.size);
1877 	}
1878 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
1879 		if ((buflen -= 4) < 0)
1880 			goto out_resource;
1881 		WRITE32(1);
1882 	}
1883 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
1884 		if ((buflen -= 4) < 0)
1885 			goto out_resource;
1886 		WRITE32(1);
1887 	}
1888 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
1889 		if ((buflen -= 4) < 0)
1890 			goto out_resource;
1891 		WRITE32(0);
1892 	}
1893 	if (bmval0 & FATTR4_WORD0_FSID) {
1894 		if ((buflen -= 16) < 0)
1895 			goto out_resource;
1896 		if (exp->ex_fslocs.migrated) {
1897 			WRITE64(NFS4_REFERRAL_FSID_MAJOR);
1898 			WRITE64(NFS4_REFERRAL_FSID_MINOR);
1899 		} else switch(fsid_source(fhp)) {
1900 		case FSIDSOURCE_FSID:
1901 			WRITE64((u64)exp->ex_fsid);
1902 			WRITE64((u64)0);
1903 			break;
1904 		case FSIDSOURCE_DEV:
1905 			WRITE32(0);
1906 			WRITE32(MAJOR(stat.dev));
1907 			WRITE32(0);
1908 			WRITE32(MINOR(stat.dev));
1909 			break;
1910 		case FSIDSOURCE_UUID:
1911 			WRITEMEM(exp->ex_uuid, 16);
1912 			break;
1913 		}
1914 	}
1915 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
1916 		if ((buflen -= 4) < 0)
1917 			goto out_resource;
1918 		WRITE32(0);
1919 	}
1920 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
1921 		if ((buflen -= 4) < 0)
1922 			goto out_resource;
1923 		WRITE32(nfsd4_lease);
1924 	}
1925 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
1926 		if ((buflen -= 4) < 0)
1927 			goto out_resource;
1928 		WRITE32(rdattr_err);
1929 	}
1930 	if (bmval0 & FATTR4_WORD0_ACL) {
1931 		struct nfs4_ace *ace;
1932 
1933 		if (acl == NULL) {
1934 			if ((buflen -= 4) < 0)
1935 				goto out_resource;
1936 
1937 			WRITE32(0);
1938 			goto out_acl;
1939 		}
1940 		if ((buflen -= 4) < 0)
1941 			goto out_resource;
1942 		WRITE32(acl->naces);
1943 
1944 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
1945 			if ((buflen -= 4*3) < 0)
1946 				goto out_resource;
1947 			WRITE32(ace->type);
1948 			WRITE32(ace->flag);
1949 			WRITE32(ace->access_mask & NFS4_ACE_MASK_ALL);
1950 			status = nfsd4_encode_aclname(rqstp, ace->whotype,
1951 				ace->who, ace->flag & NFS4_ACE_IDENTIFIER_GROUP,
1952 				&p, &buflen);
1953 			if (status == nfserr_resource)
1954 				goto out_resource;
1955 			if (status)
1956 				goto out;
1957 		}
1958 	}
1959 out_acl:
1960 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
1961 		if ((buflen -= 4) < 0)
1962 			goto out_resource;
1963 		WRITE32(aclsupport ?
1964 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
1965 	}
1966 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
1967 		if ((buflen -= 4) < 0)
1968 			goto out_resource;
1969 		WRITE32(1);
1970 	}
1971 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
1972 		if ((buflen -= 4) < 0)
1973 			goto out_resource;
1974 		WRITE32(1);
1975 	}
1976 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
1977 		if ((buflen -= 4) < 0)
1978 			goto out_resource;
1979 		WRITE32(1);
1980 	}
1981 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
1982 		if ((buflen -= 4) < 0)
1983 			goto out_resource;
1984 		WRITE32(1);
1985 	}
1986 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
1987 		buflen -= (XDR_QUADLEN(fhp->fh_handle.fh_size) << 2) + 4;
1988 		if (buflen < 0)
1989 			goto out_resource;
1990 		WRITE32(fhp->fh_handle.fh_size);
1991 		WRITEMEM(&fhp->fh_handle.fh_base, fhp->fh_handle.fh_size);
1992 	}
1993 	if (bmval0 & FATTR4_WORD0_FILEID) {
1994 		if ((buflen -= 8) < 0)
1995 			goto out_resource;
1996 		WRITE64(stat.ino);
1997 	}
1998 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
1999 		if ((buflen -= 8) < 0)
2000 			goto out_resource;
2001 		WRITE64((u64) statfs.f_ffree);
2002 	}
2003 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2004 		if ((buflen -= 8) < 0)
2005 			goto out_resource;
2006 		WRITE64((u64) statfs.f_ffree);
2007 	}
2008 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2009 		if ((buflen -= 8) < 0)
2010 			goto out_resource;
2011 		WRITE64((u64) statfs.f_files);
2012 	}
2013 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2014 		status = nfsd4_encode_fs_locations(rqstp, exp, &p, &buflen);
2015 		if (status == nfserr_resource)
2016 			goto out_resource;
2017 		if (status)
2018 			goto out;
2019 	}
2020 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2021 		if ((buflen -= 4) < 0)
2022 			goto out_resource;
2023 		WRITE32(1);
2024 	}
2025 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2026 		if ((buflen -= 8) < 0)
2027 			goto out_resource;
2028 		WRITE64(~(u64)0);
2029 	}
2030 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2031 		if ((buflen -= 4) < 0)
2032 			goto out_resource;
2033 		WRITE32(255);
2034 	}
2035 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2036 		if ((buflen -= 4) < 0)
2037 			goto out_resource;
2038 		WRITE32(statfs.f_namelen);
2039 	}
2040 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2041 		if ((buflen -= 8) < 0)
2042 			goto out_resource;
2043 		WRITE64((u64) svc_max_payload(rqstp));
2044 	}
2045 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2046 		if ((buflen -= 8) < 0)
2047 			goto out_resource;
2048 		WRITE64((u64) svc_max_payload(rqstp));
2049 	}
2050 	if (bmval1 & FATTR4_WORD1_MODE) {
2051 		if ((buflen -= 4) < 0)
2052 			goto out_resource;
2053 		WRITE32(stat.mode & S_IALLUGO);
2054 	}
2055 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2056 		if ((buflen -= 4) < 0)
2057 			goto out_resource;
2058 		WRITE32(1);
2059 	}
2060 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2061 		if ((buflen -= 4) < 0)
2062 			goto out_resource;
2063 		WRITE32(stat.nlink);
2064 	}
2065 	if (bmval1 & FATTR4_WORD1_OWNER) {
2066 		status = nfsd4_encode_user(rqstp, stat.uid, &p, &buflen);
2067 		if (status == nfserr_resource)
2068 			goto out_resource;
2069 		if (status)
2070 			goto out;
2071 	}
2072 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2073 		status = nfsd4_encode_group(rqstp, stat.gid, &p, &buflen);
2074 		if (status == nfserr_resource)
2075 			goto out_resource;
2076 		if (status)
2077 			goto out;
2078 	}
2079 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2080 		if ((buflen -= 8) < 0)
2081 			goto out_resource;
2082 		WRITE32((u32) MAJOR(stat.rdev));
2083 		WRITE32((u32) MINOR(stat.rdev));
2084 	}
2085 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2086 		if ((buflen -= 8) < 0)
2087 			goto out_resource;
2088 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2089 		WRITE64(dummy64);
2090 	}
2091 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2092 		if ((buflen -= 8) < 0)
2093 			goto out_resource;
2094 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2095 		WRITE64(dummy64);
2096 	}
2097 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2098 		if ((buflen -= 8) < 0)
2099 			goto out_resource;
2100 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2101 		WRITE64(dummy64);
2102 	}
2103 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2104 		if ((buflen -= 8) < 0)
2105 			goto out_resource;
2106 		dummy64 = (u64)stat.blocks << 9;
2107 		WRITE64(dummy64);
2108 	}
2109 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2110 		if ((buflen -= 12) < 0)
2111 			goto out_resource;
2112 		WRITE32(0);
2113 		WRITE32(stat.atime.tv_sec);
2114 		WRITE32(stat.atime.tv_nsec);
2115 	}
2116 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2117 		if ((buflen -= 12) < 0)
2118 			goto out_resource;
2119 		WRITE32(0);
2120 		WRITE32(1);
2121 		WRITE32(0);
2122 	}
2123 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2124 		if ((buflen -= 12) < 0)
2125 			goto out_resource;
2126 		WRITE32(0);
2127 		WRITE32(stat.ctime.tv_sec);
2128 		WRITE32(stat.ctime.tv_nsec);
2129 	}
2130 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2131 		if ((buflen -= 12) < 0)
2132 			goto out_resource;
2133 		WRITE32(0);
2134 		WRITE32(stat.mtime.tv_sec);
2135 		WRITE32(stat.mtime.tv_nsec);
2136 	}
2137 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2138 		if ((buflen -= 8) < 0)
2139                 	goto out_resource;
2140 		/*
2141 		 * Get parent's attributes if not ignoring crossmount
2142 		 * and this is the root of a cross-mounted filesystem.
2143 		 */
2144 		if (ignore_crossmnt == 0 &&
2145 		    dentry == exp->ex_path.mnt->mnt_root) {
2146 			struct path path = exp->ex_path;
2147 			path_get(&path);
2148 			while (follow_up(&path)) {
2149 				if (path.dentry != path.mnt->mnt_root)
2150 					break;
2151 			}
2152 			err = vfs_getattr(path.mnt, path.dentry, &stat);
2153 			path_put(&path);
2154 			if (err)
2155 				goto out_nfserr;
2156 		}
2157 		WRITE64(stat.ino);
2158 	}
2159 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2160 		WRITE32(3);
2161 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD0);
2162 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD1);
2163 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD2);
2164 	}
2165 
2166 	*attrlenp = htonl((char *)p - (char *)attrlenp - 4);
2167 	*countp = p - buffer;
2168 	status = nfs_ok;
2169 
2170 out:
2171 	kfree(acl);
2172 	if (fhp == &tempfh)
2173 		fh_put(&tempfh);
2174 	return status;
2175 out_nfserr:
2176 	status = nfserrno(err);
2177 	goto out;
2178 out_resource:
2179 	*countp = 0;
2180 	status = nfserr_resource;
2181 	goto out;
2182 out_serverfault:
2183 	status = nfserr_serverfault;
2184 	goto out;
2185 }
2186 
2187 static inline int attributes_need_mount(u32 *bmval)
2188 {
2189 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2190 		return 1;
2191 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2192 		return 1;
2193 	return 0;
2194 }
2195 
2196 static __be32
2197 nfsd4_encode_dirent_fattr(struct nfsd4_readdir *cd,
2198 		const char *name, int namlen, __be32 *p, int *buflen)
2199 {
2200 	struct svc_export *exp = cd->rd_fhp->fh_export;
2201 	struct dentry *dentry;
2202 	__be32 nfserr;
2203 	int ignore_crossmnt = 0;
2204 
2205 	dentry = lookup_one_len(name, cd->rd_fhp->fh_dentry, namlen);
2206 	if (IS_ERR(dentry))
2207 		return nfserrno(PTR_ERR(dentry));
2208 	if (!dentry->d_inode) {
2209 		/*
2210 		 * nfsd_buffered_readdir drops the i_mutex between
2211 		 * readdir and calling this callback, leaving a window
2212 		 * where this directory entry could have gone away.
2213 		 */
2214 		dput(dentry);
2215 		return nfserr_noent;
2216 	}
2217 
2218 	exp_get(exp);
2219 	/*
2220 	 * In the case of a mountpoint, the client may be asking for
2221 	 * attributes that are only properties of the underlying filesystem
2222 	 * as opposed to the cross-mounted file system. In such a case,
2223 	 * we will not follow the cross mount and will fill the attribtutes
2224 	 * directly from the mountpoint dentry.
2225 	 */
2226 	if (nfsd_mountpoint(dentry, exp)) {
2227 		int err;
2228 
2229 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
2230 				&& !attributes_need_mount(cd->rd_bmval)) {
2231 			ignore_crossmnt = 1;
2232 			goto out_encode;
2233 		}
2234 		/*
2235 		 * Why the heck aren't we just using nfsd_lookup??
2236 		 * Different "."/".." handling?  Something else?
2237 		 * At least, add a comment here to explain....
2238 		 */
2239 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
2240 		if (err) {
2241 			nfserr = nfserrno(err);
2242 			goto out_put;
2243 		}
2244 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
2245 		if (nfserr)
2246 			goto out_put;
2247 
2248 	}
2249 out_encode:
2250 	nfserr = nfsd4_encode_fattr(NULL, exp, dentry, p, buflen, cd->rd_bmval,
2251 					cd->rd_rqstp, ignore_crossmnt);
2252 out_put:
2253 	dput(dentry);
2254 	exp_put(exp);
2255 	return nfserr;
2256 }
2257 
2258 static __be32 *
2259 nfsd4_encode_rdattr_error(__be32 *p, int buflen, __be32 nfserr)
2260 {
2261 	__be32 *attrlenp;
2262 
2263 	if (buflen < 6)
2264 		return NULL;
2265 	*p++ = htonl(2);
2266 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
2267 	*p++ = htonl(0);			 /* bmval1 */
2268 
2269 	attrlenp = p++;
2270 	*p++ = nfserr;       /* no htonl */
2271 	*attrlenp = htonl((char *)p - (char *)attrlenp - 4);
2272 	return p;
2273 }
2274 
2275 static int
2276 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
2277 		    loff_t offset, u64 ino, unsigned int d_type)
2278 {
2279 	struct readdir_cd *ccd = ccdv;
2280 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
2281 	int buflen;
2282 	__be32 *p = cd->buffer;
2283 	__be32 *cookiep;
2284 	__be32 nfserr = nfserr_toosmall;
2285 
2286 	/* In nfsv4, "." and ".." never make it onto the wire.. */
2287 	if (name && isdotent(name, namlen)) {
2288 		cd->common.err = nfs_ok;
2289 		return 0;
2290 	}
2291 
2292 	if (cd->offset)
2293 		xdr_encode_hyper(cd->offset, (u64) offset);
2294 
2295 	buflen = cd->buflen - 4 - XDR_QUADLEN(namlen);
2296 	if (buflen < 0)
2297 		goto fail;
2298 
2299 	*p++ = xdr_one;                             /* mark entry present */
2300 	cookiep = p;
2301 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
2302 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
2303 
2304 	nfserr = nfsd4_encode_dirent_fattr(cd, name, namlen, p, &buflen);
2305 	switch (nfserr) {
2306 	case nfs_ok:
2307 		p += buflen;
2308 		break;
2309 	case nfserr_resource:
2310 		nfserr = nfserr_toosmall;
2311 		goto fail;
2312 	case nfserr_dropit:
2313 		goto fail;
2314 	case nfserr_noent:
2315 		goto skip_entry;
2316 	default:
2317 		/*
2318 		 * If the client requested the RDATTR_ERROR attribute,
2319 		 * we stuff the error code into this attribute
2320 		 * and continue.  If this attribute was not requested,
2321 		 * then in accordance with the spec, we fail the
2322 		 * entire READDIR operation(!)
2323 		 */
2324 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
2325 			goto fail;
2326 		p = nfsd4_encode_rdattr_error(p, buflen, nfserr);
2327 		if (p == NULL) {
2328 			nfserr = nfserr_toosmall;
2329 			goto fail;
2330 		}
2331 	}
2332 	cd->buflen -= (p - cd->buffer);
2333 	cd->buffer = p;
2334 	cd->offset = cookiep;
2335 skip_entry:
2336 	cd->common.err = nfs_ok;
2337 	return 0;
2338 fail:
2339 	cd->common.err = nfserr;
2340 	return -EINVAL;
2341 }
2342 
2343 static void
2344 nfsd4_encode_stateid(struct nfsd4_compoundres *resp, stateid_t *sid)
2345 {
2346 	__be32 *p;
2347 
2348 	RESERVE_SPACE(sizeof(stateid_t));
2349 	WRITE32(sid->si_generation);
2350 	WRITEMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
2351 	ADJUST_ARGS();
2352 }
2353 
2354 static __be32
2355 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
2356 {
2357 	__be32 *p;
2358 
2359 	if (!nfserr) {
2360 		RESERVE_SPACE(8);
2361 		WRITE32(access->ac_supported);
2362 		WRITE32(access->ac_resp_access);
2363 		ADJUST_ARGS();
2364 	}
2365 	return nfserr;
2366 }
2367 
2368 static __be32
2369 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
2370 {
2371 	ENCODE_SEQID_OP_HEAD;
2372 
2373 	if (!nfserr)
2374 		nfsd4_encode_stateid(resp, &close->cl_stateid);
2375 
2376 	ENCODE_SEQID_OP_TAIL(close->cl_stateowner);
2377 	return nfserr;
2378 }
2379 
2380 
2381 static __be32
2382 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
2383 {
2384 	__be32 *p;
2385 
2386 	if (!nfserr) {
2387 		RESERVE_SPACE(8);
2388 		WRITEMEM(commit->co_verf.data, 8);
2389 		ADJUST_ARGS();
2390 	}
2391 	return nfserr;
2392 }
2393 
2394 static __be32
2395 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
2396 {
2397 	__be32 *p;
2398 
2399 	if (!nfserr) {
2400 		RESERVE_SPACE(32);
2401 		write_cinfo(&p, &create->cr_cinfo);
2402 		WRITE32(2);
2403 		WRITE32(create->cr_bmval[0]);
2404 		WRITE32(create->cr_bmval[1]);
2405 		ADJUST_ARGS();
2406 	}
2407 	return nfserr;
2408 }
2409 
2410 static __be32
2411 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
2412 {
2413 	struct svc_fh *fhp = getattr->ga_fhp;
2414 	int buflen;
2415 
2416 	if (nfserr)
2417 		return nfserr;
2418 
2419 	buflen = resp->end - resp->p - (COMPOUND_ERR_SLACK_SPACE >> 2);
2420 	nfserr = nfsd4_encode_fattr(fhp, fhp->fh_export, fhp->fh_dentry,
2421 				    resp->p, &buflen, getattr->ga_bmval,
2422 				    resp->rqstp, 0);
2423 	if (!nfserr)
2424 		resp->p += buflen;
2425 	return nfserr;
2426 }
2427 
2428 static __be32
2429 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
2430 {
2431 	struct svc_fh *fhp = *fhpp;
2432 	unsigned int len;
2433 	__be32 *p;
2434 
2435 	if (!nfserr) {
2436 		len = fhp->fh_handle.fh_size;
2437 		RESERVE_SPACE(len + 4);
2438 		WRITE32(len);
2439 		WRITEMEM(&fhp->fh_handle.fh_base, len);
2440 		ADJUST_ARGS();
2441 	}
2442 	return nfserr;
2443 }
2444 
2445 /*
2446 * Including all fields other than the name, a LOCK4denied structure requires
2447 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
2448 */
2449 static void
2450 nfsd4_encode_lock_denied(struct nfsd4_compoundres *resp, struct nfsd4_lock_denied *ld)
2451 {
2452 	__be32 *p;
2453 
2454 	RESERVE_SPACE(32 + XDR_LEN(ld->ld_sop ? ld->ld_sop->so_owner.len : 0));
2455 	WRITE64(ld->ld_start);
2456 	WRITE64(ld->ld_length);
2457 	WRITE32(ld->ld_type);
2458 	if (ld->ld_sop) {
2459 		WRITEMEM(&ld->ld_clientid, 8);
2460 		WRITE32(ld->ld_sop->so_owner.len);
2461 		WRITEMEM(ld->ld_sop->so_owner.data, ld->ld_sop->so_owner.len);
2462 		kref_put(&ld->ld_sop->so_ref, nfs4_free_stateowner);
2463 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
2464 		WRITE64((u64)0); /* clientid */
2465 		WRITE32(0); /* length of owner name */
2466 	}
2467 	ADJUST_ARGS();
2468 }
2469 
2470 static __be32
2471 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
2472 {
2473 	ENCODE_SEQID_OP_HEAD;
2474 
2475 	if (!nfserr)
2476 		nfsd4_encode_stateid(resp, &lock->lk_resp_stateid);
2477 	else if (nfserr == nfserr_denied)
2478 		nfsd4_encode_lock_denied(resp, &lock->lk_denied);
2479 
2480 	ENCODE_SEQID_OP_TAIL(lock->lk_replay_owner);
2481 	return nfserr;
2482 }
2483 
2484 static __be32
2485 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
2486 {
2487 	if (nfserr == nfserr_denied)
2488 		nfsd4_encode_lock_denied(resp, &lockt->lt_denied);
2489 	return nfserr;
2490 }
2491 
2492 static __be32
2493 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
2494 {
2495 	ENCODE_SEQID_OP_HEAD;
2496 
2497 	if (!nfserr)
2498 		nfsd4_encode_stateid(resp, &locku->lu_stateid);
2499 
2500 	ENCODE_SEQID_OP_TAIL(locku->lu_stateowner);
2501 	return nfserr;
2502 }
2503 
2504 
2505 static __be32
2506 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
2507 {
2508 	__be32 *p;
2509 
2510 	if (!nfserr) {
2511 		RESERVE_SPACE(20);
2512 		write_cinfo(&p, &link->li_cinfo);
2513 		ADJUST_ARGS();
2514 	}
2515 	return nfserr;
2516 }
2517 
2518 
2519 static __be32
2520 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
2521 {
2522 	__be32 *p;
2523 	ENCODE_SEQID_OP_HEAD;
2524 
2525 	if (nfserr)
2526 		goto out;
2527 
2528 	nfsd4_encode_stateid(resp, &open->op_stateid);
2529 	RESERVE_SPACE(40);
2530 	write_cinfo(&p, &open->op_cinfo);
2531 	WRITE32(open->op_rflags);
2532 	WRITE32(2);
2533 	WRITE32(open->op_bmval[0]);
2534 	WRITE32(open->op_bmval[1]);
2535 	WRITE32(open->op_delegate_type);
2536 	ADJUST_ARGS();
2537 
2538 	switch (open->op_delegate_type) {
2539 	case NFS4_OPEN_DELEGATE_NONE:
2540 		break;
2541 	case NFS4_OPEN_DELEGATE_READ:
2542 		nfsd4_encode_stateid(resp, &open->op_delegate_stateid);
2543 		RESERVE_SPACE(20);
2544 		WRITE32(open->op_recall);
2545 
2546 		/*
2547 		 * TODO: ACE's in delegations
2548 		 */
2549 		WRITE32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
2550 		WRITE32(0);
2551 		WRITE32(0);
2552 		WRITE32(0);   /* XXX: is NULL principal ok? */
2553 		ADJUST_ARGS();
2554 		break;
2555 	case NFS4_OPEN_DELEGATE_WRITE:
2556 		nfsd4_encode_stateid(resp, &open->op_delegate_stateid);
2557 		RESERVE_SPACE(32);
2558 		WRITE32(0);
2559 
2560 		/*
2561 		 * TODO: space_limit's in delegations
2562 		 */
2563 		WRITE32(NFS4_LIMIT_SIZE);
2564 		WRITE32(~(u32)0);
2565 		WRITE32(~(u32)0);
2566 
2567 		/*
2568 		 * TODO: ACE's in delegations
2569 		 */
2570 		WRITE32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
2571 		WRITE32(0);
2572 		WRITE32(0);
2573 		WRITE32(0);   /* XXX: is NULL principal ok? */
2574 		ADJUST_ARGS();
2575 		break;
2576 	default:
2577 		BUG();
2578 	}
2579 	/* XXX save filehandle here */
2580 out:
2581 	ENCODE_SEQID_OP_TAIL(open->op_stateowner);
2582 	return nfserr;
2583 }
2584 
2585 static __be32
2586 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
2587 {
2588 	ENCODE_SEQID_OP_HEAD;
2589 
2590 	if (!nfserr)
2591 		nfsd4_encode_stateid(resp, &oc->oc_resp_stateid);
2592 
2593 	ENCODE_SEQID_OP_TAIL(oc->oc_stateowner);
2594 	return nfserr;
2595 }
2596 
2597 static __be32
2598 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
2599 {
2600 	ENCODE_SEQID_OP_HEAD;
2601 
2602 	if (!nfserr)
2603 		nfsd4_encode_stateid(resp, &od->od_stateid);
2604 
2605 	ENCODE_SEQID_OP_TAIL(od->od_stateowner);
2606 	return nfserr;
2607 }
2608 
2609 static __be32
2610 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
2611 		  struct nfsd4_read *read)
2612 {
2613 	u32 eof;
2614 	int v, pn;
2615 	unsigned long maxcount;
2616 	long len;
2617 	__be32 *p;
2618 
2619 	if (nfserr)
2620 		return nfserr;
2621 	if (resp->xbuf->page_len)
2622 		return nfserr_resource;
2623 
2624 	RESERVE_SPACE(8); /* eof flag and byte count */
2625 
2626 	maxcount = svc_max_payload(resp->rqstp);
2627 	if (maxcount > read->rd_length)
2628 		maxcount = read->rd_length;
2629 
2630 	len = maxcount;
2631 	v = 0;
2632 	while (len > 0) {
2633 		pn = resp->rqstp->rq_resused++;
2634 		resp->rqstp->rq_vec[v].iov_base =
2635 			page_address(resp->rqstp->rq_respages[pn]);
2636 		resp->rqstp->rq_vec[v].iov_len =
2637 			len < PAGE_SIZE ? len : PAGE_SIZE;
2638 		v++;
2639 		len -= PAGE_SIZE;
2640 	}
2641 	read->rd_vlen = v;
2642 
2643 	nfserr = nfsd_read_file(read->rd_rqstp, read->rd_fhp, read->rd_filp,
2644 			read->rd_offset, resp->rqstp->rq_vec, read->rd_vlen,
2645 			&maxcount);
2646 
2647 	if (nfserr == nfserr_symlink)
2648 		nfserr = nfserr_inval;
2649 	if (nfserr)
2650 		return nfserr;
2651 	eof = (read->rd_offset + maxcount >=
2652 	       read->rd_fhp->fh_dentry->d_inode->i_size);
2653 
2654 	WRITE32(eof);
2655 	WRITE32(maxcount);
2656 	ADJUST_ARGS();
2657 	resp->xbuf->head[0].iov_len = (char*)p
2658 					- (char*)resp->xbuf->head[0].iov_base;
2659 	resp->xbuf->page_len = maxcount;
2660 
2661 	/* Use rest of head for padding and remaining ops: */
2662 	resp->xbuf->tail[0].iov_base = p;
2663 	resp->xbuf->tail[0].iov_len = 0;
2664 	if (maxcount&3) {
2665 		RESERVE_SPACE(4);
2666 		WRITE32(0);
2667 		resp->xbuf->tail[0].iov_base += maxcount&3;
2668 		resp->xbuf->tail[0].iov_len = 4 - (maxcount&3);
2669 		ADJUST_ARGS();
2670 	}
2671 	return 0;
2672 }
2673 
2674 static __be32
2675 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
2676 {
2677 	int maxcount;
2678 	char *page;
2679 	__be32 *p;
2680 
2681 	if (nfserr)
2682 		return nfserr;
2683 	if (resp->xbuf->page_len)
2684 		return nfserr_resource;
2685 
2686 	page = page_address(resp->rqstp->rq_respages[resp->rqstp->rq_resused++]);
2687 
2688 	maxcount = PAGE_SIZE;
2689 	RESERVE_SPACE(4);
2690 
2691 	/*
2692 	 * XXX: By default, the ->readlink() VFS op will truncate symlinks
2693 	 * if they would overflow the buffer.  Is this kosher in NFSv4?  If
2694 	 * not, one easy fix is: if ->readlink() precisely fills the buffer,
2695 	 * assume that truncation occurred, and return NFS4ERR_RESOURCE.
2696 	 */
2697 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp, page, &maxcount);
2698 	if (nfserr == nfserr_isdir)
2699 		return nfserr_inval;
2700 	if (nfserr)
2701 		return nfserr;
2702 
2703 	WRITE32(maxcount);
2704 	ADJUST_ARGS();
2705 	resp->xbuf->head[0].iov_len = (char*)p
2706 				- (char*)resp->xbuf->head[0].iov_base;
2707 	resp->xbuf->page_len = maxcount;
2708 
2709 	/* Use rest of head for padding and remaining ops: */
2710 	resp->xbuf->tail[0].iov_base = p;
2711 	resp->xbuf->tail[0].iov_len = 0;
2712 	if (maxcount&3) {
2713 		RESERVE_SPACE(4);
2714 		WRITE32(0);
2715 		resp->xbuf->tail[0].iov_base += maxcount&3;
2716 		resp->xbuf->tail[0].iov_len = 4 - (maxcount&3);
2717 		ADJUST_ARGS();
2718 	}
2719 	return 0;
2720 }
2721 
2722 static __be32
2723 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
2724 {
2725 	int maxcount;
2726 	loff_t offset;
2727 	__be32 *page, *savep, *tailbase;
2728 	__be32 *p;
2729 
2730 	if (nfserr)
2731 		return nfserr;
2732 	if (resp->xbuf->page_len)
2733 		return nfserr_resource;
2734 
2735 	RESERVE_SPACE(8);  /* verifier */
2736 	savep = p;
2737 
2738 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
2739 	WRITE32(0);
2740 	WRITE32(0);
2741 	ADJUST_ARGS();
2742 	resp->xbuf->head[0].iov_len = ((char*)resp->p) - (char*)resp->xbuf->head[0].iov_base;
2743 	tailbase = p;
2744 
2745 	maxcount = PAGE_SIZE;
2746 	if (maxcount > readdir->rd_maxcount)
2747 		maxcount = readdir->rd_maxcount;
2748 
2749 	/*
2750 	 * Convert from bytes to words, account for the two words already
2751 	 * written, make sure to leave two words at the end for the next
2752 	 * pointer and eof field.
2753 	 */
2754 	maxcount = (maxcount >> 2) - 4;
2755 	if (maxcount < 0) {
2756 		nfserr =  nfserr_toosmall;
2757 		goto err_no_verf;
2758 	}
2759 
2760 	page = page_address(resp->rqstp->rq_respages[resp->rqstp->rq_resused++]);
2761 	readdir->common.err = 0;
2762 	readdir->buflen = maxcount;
2763 	readdir->buffer = page;
2764 	readdir->offset = NULL;
2765 
2766 	offset = readdir->rd_cookie;
2767 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
2768 			      &offset,
2769 			      &readdir->common, nfsd4_encode_dirent);
2770 	if (nfserr == nfs_ok &&
2771 	    readdir->common.err == nfserr_toosmall &&
2772 	    readdir->buffer == page)
2773 		nfserr = nfserr_toosmall;
2774 	if (nfserr == nfserr_symlink)
2775 		nfserr = nfserr_notdir;
2776 	if (nfserr)
2777 		goto err_no_verf;
2778 
2779 	if (readdir->offset)
2780 		xdr_encode_hyper(readdir->offset, offset);
2781 
2782 	p = readdir->buffer;
2783 	*p++ = 0;	/* no more entries */
2784 	*p++ = htonl(readdir->common.err == nfserr_eof);
2785 	resp->xbuf->page_len = ((char*)p) - (char*)page_address(
2786 		resp->rqstp->rq_respages[resp->rqstp->rq_resused-1]);
2787 
2788 	/* Use rest of head for padding and remaining ops: */
2789 	resp->xbuf->tail[0].iov_base = tailbase;
2790 	resp->xbuf->tail[0].iov_len = 0;
2791 	resp->p = resp->xbuf->tail[0].iov_base;
2792 	resp->end = resp->p + (PAGE_SIZE - resp->xbuf->head[0].iov_len)/4;
2793 
2794 	return 0;
2795 err_no_verf:
2796 	p = savep;
2797 	ADJUST_ARGS();
2798 	return nfserr;
2799 }
2800 
2801 static __be32
2802 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
2803 {
2804 	__be32 *p;
2805 
2806 	if (!nfserr) {
2807 		RESERVE_SPACE(20);
2808 		write_cinfo(&p, &remove->rm_cinfo);
2809 		ADJUST_ARGS();
2810 	}
2811 	return nfserr;
2812 }
2813 
2814 static __be32
2815 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
2816 {
2817 	__be32 *p;
2818 
2819 	if (!nfserr) {
2820 		RESERVE_SPACE(40);
2821 		write_cinfo(&p, &rename->rn_sinfo);
2822 		write_cinfo(&p, &rename->rn_tinfo);
2823 		ADJUST_ARGS();
2824 	}
2825 	return nfserr;
2826 }
2827 
2828 static __be32
2829 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
2830 		     struct nfsd4_secinfo *secinfo)
2831 {
2832 	int i = 0;
2833 	struct svc_export *exp = secinfo->si_exp;
2834 	u32 nflavs;
2835 	struct exp_flavor_info *flavs;
2836 	struct exp_flavor_info def_flavs[2];
2837 	__be32 *p;
2838 
2839 	if (nfserr)
2840 		goto out;
2841 	if (exp->ex_nflavors) {
2842 		flavs = exp->ex_flavors;
2843 		nflavs = exp->ex_nflavors;
2844 	} else { /* Handling of some defaults in absence of real secinfo: */
2845 		flavs = def_flavs;
2846 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
2847 			nflavs = 2;
2848 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
2849 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
2850 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
2851 			nflavs = 1;
2852 			flavs[0].pseudoflavor
2853 					= svcauth_gss_flavor(exp->ex_client);
2854 		} else {
2855 			nflavs = 1;
2856 			flavs[0].pseudoflavor
2857 					= exp->ex_client->flavour->flavour;
2858 		}
2859 	}
2860 
2861 	RESERVE_SPACE(4);
2862 	WRITE32(nflavs);
2863 	ADJUST_ARGS();
2864 	for (i = 0; i < nflavs; i++) {
2865 		u32 flav = flavs[i].pseudoflavor;
2866 		struct gss_api_mech *gm = gss_mech_get_by_pseudoflavor(flav);
2867 
2868 		if (gm) {
2869 			RESERVE_SPACE(4);
2870 			WRITE32(RPC_AUTH_GSS);
2871 			ADJUST_ARGS();
2872 			RESERVE_SPACE(4 + gm->gm_oid.len);
2873 			WRITE32(gm->gm_oid.len);
2874 			WRITEMEM(gm->gm_oid.data, gm->gm_oid.len);
2875 			ADJUST_ARGS();
2876 			RESERVE_SPACE(4);
2877 			WRITE32(0); /* qop */
2878 			ADJUST_ARGS();
2879 			RESERVE_SPACE(4);
2880 			WRITE32(gss_pseudoflavor_to_service(gm, flav));
2881 			ADJUST_ARGS();
2882 			gss_mech_put(gm);
2883 		} else {
2884 			RESERVE_SPACE(4);
2885 			WRITE32(flav);
2886 			ADJUST_ARGS();
2887 		}
2888 	}
2889 out:
2890 	if (exp)
2891 		exp_put(exp);
2892 	return nfserr;
2893 }
2894 
2895 /*
2896  * The SETATTR encode routine is special -- it always encodes a bitmap,
2897  * regardless of the error status.
2898  */
2899 static __be32
2900 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
2901 {
2902 	__be32 *p;
2903 
2904 	RESERVE_SPACE(12);
2905 	if (nfserr) {
2906 		WRITE32(2);
2907 		WRITE32(0);
2908 		WRITE32(0);
2909 	}
2910 	else {
2911 		WRITE32(2);
2912 		WRITE32(setattr->sa_bmval[0]);
2913 		WRITE32(setattr->sa_bmval[1]);
2914 	}
2915 	ADJUST_ARGS();
2916 	return nfserr;
2917 }
2918 
2919 static __be32
2920 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
2921 {
2922 	__be32 *p;
2923 
2924 	if (!nfserr) {
2925 		RESERVE_SPACE(8 + sizeof(nfs4_verifier));
2926 		WRITEMEM(&scd->se_clientid, 8);
2927 		WRITEMEM(&scd->se_confirm, sizeof(nfs4_verifier));
2928 		ADJUST_ARGS();
2929 	}
2930 	else if (nfserr == nfserr_clid_inuse) {
2931 		RESERVE_SPACE(8);
2932 		WRITE32(0);
2933 		WRITE32(0);
2934 		ADJUST_ARGS();
2935 	}
2936 	return nfserr;
2937 }
2938 
2939 static __be32
2940 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
2941 {
2942 	__be32 *p;
2943 
2944 	if (!nfserr) {
2945 		RESERVE_SPACE(16);
2946 		WRITE32(write->wr_bytes_written);
2947 		WRITE32(write->wr_how_written);
2948 		WRITEMEM(write->wr_verifier.data, 8);
2949 		ADJUST_ARGS();
2950 	}
2951 	return nfserr;
2952 }
2953 
2954 static __be32
2955 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, int nfserr,
2956 			 struct nfsd4_exchange_id *exid)
2957 {
2958 	__be32 *p;
2959 	char *major_id;
2960 	char *server_scope;
2961 	int major_id_sz;
2962 	int server_scope_sz;
2963 	uint64_t minor_id = 0;
2964 
2965 	if (nfserr)
2966 		return nfserr;
2967 
2968 	major_id = utsname()->nodename;
2969 	major_id_sz = strlen(major_id);
2970 	server_scope = utsname()->nodename;
2971 	server_scope_sz = strlen(server_scope);
2972 
2973 	RESERVE_SPACE(
2974 		8 /* eir_clientid */ +
2975 		4 /* eir_sequenceid */ +
2976 		4 /* eir_flags */ +
2977 		4 /* spr_how (SP4_NONE) */ +
2978 		8 /* so_minor_id */ +
2979 		4 /* so_major_id.len */ +
2980 		(XDR_QUADLEN(major_id_sz) * 4) +
2981 		4 /* eir_server_scope.len */ +
2982 		(XDR_QUADLEN(server_scope_sz) * 4) +
2983 		4 /* eir_server_impl_id.count (0) */);
2984 
2985 	WRITEMEM(&exid->clientid, 8);
2986 	WRITE32(exid->seqid);
2987 	WRITE32(exid->flags);
2988 
2989 	/* state_protect4_r. Currently only support SP4_NONE */
2990 	BUG_ON(exid->spa_how != SP4_NONE);
2991 	WRITE32(exid->spa_how);
2992 
2993 	/* The server_owner struct */
2994 	WRITE64(minor_id);      /* Minor id */
2995 	/* major id */
2996 	WRITE32(major_id_sz);
2997 	WRITEMEM(major_id, major_id_sz);
2998 
2999 	/* Server scope */
3000 	WRITE32(server_scope_sz);
3001 	WRITEMEM(server_scope, server_scope_sz);
3002 
3003 	/* Implementation id */
3004 	WRITE32(0);	/* zero length nfs_impl_id4 array */
3005 	ADJUST_ARGS();
3006 	return 0;
3007 }
3008 
3009 static __be32
3010 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, int nfserr,
3011 			    struct nfsd4_create_session *sess)
3012 {
3013 	__be32 *p;
3014 
3015 	if (nfserr)
3016 		return nfserr;
3017 
3018 	RESERVE_SPACE(24);
3019 	WRITEMEM(sess->sessionid.data, NFS4_MAX_SESSIONID_LEN);
3020 	WRITE32(sess->seqid);
3021 	WRITE32(sess->flags);
3022 	ADJUST_ARGS();
3023 
3024 	RESERVE_SPACE(28);
3025 	WRITE32(0); /* headerpadsz */
3026 	WRITE32(sess->fore_channel.maxreq_sz);
3027 	WRITE32(sess->fore_channel.maxresp_sz);
3028 	WRITE32(sess->fore_channel.maxresp_cached);
3029 	WRITE32(sess->fore_channel.maxops);
3030 	WRITE32(sess->fore_channel.maxreqs);
3031 	WRITE32(sess->fore_channel.nr_rdma_attrs);
3032 	ADJUST_ARGS();
3033 
3034 	if (sess->fore_channel.nr_rdma_attrs) {
3035 		RESERVE_SPACE(4);
3036 		WRITE32(sess->fore_channel.rdma_attrs);
3037 		ADJUST_ARGS();
3038 	}
3039 
3040 	RESERVE_SPACE(28);
3041 	WRITE32(0); /* headerpadsz */
3042 	WRITE32(sess->back_channel.maxreq_sz);
3043 	WRITE32(sess->back_channel.maxresp_sz);
3044 	WRITE32(sess->back_channel.maxresp_cached);
3045 	WRITE32(sess->back_channel.maxops);
3046 	WRITE32(sess->back_channel.maxreqs);
3047 	WRITE32(sess->back_channel.nr_rdma_attrs);
3048 	ADJUST_ARGS();
3049 
3050 	if (sess->back_channel.nr_rdma_attrs) {
3051 		RESERVE_SPACE(4);
3052 		WRITE32(sess->back_channel.rdma_attrs);
3053 		ADJUST_ARGS();
3054 	}
3055 	return 0;
3056 }
3057 
3058 static __be32
3059 nfsd4_encode_destroy_session(struct nfsd4_compoundres *resp, int nfserr,
3060 			     struct nfsd4_destroy_session *destroy_session)
3061 {
3062 	return nfserr;
3063 }
3064 
3065 __be32
3066 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, int nfserr,
3067 		      struct nfsd4_sequence *seq)
3068 {
3069 	__be32 *p;
3070 
3071 	if (nfserr)
3072 		return nfserr;
3073 
3074 	RESERVE_SPACE(NFS4_MAX_SESSIONID_LEN + 20);
3075 	WRITEMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
3076 	WRITE32(seq->seqid);
3077 	WRITE32(seq->slotid);
3078 	WRITE32(seq->maxslots);
3079 	/*
3080 	 * FIXME: for now:
3081 	 *   target_maxslots = maxslots
3082 	 *   status_flags = 0
3083 	 */
3084 	WRITE32(seq->maxslots);
3085 	WRITE32(0);
3086 
3087 	ADJUST_ARGS();
3088 	resp->cstate.datap = p; /* DRC cache data pointer */
3089 	return 0;
3090 }
3091 
3092 static __be32
3093 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
3094 {
3095 	return nfserr;
3096 }
3097 
3098 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
3099 
3100 /*
3101  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
3102  * since we don't need to filter out obsolete ops as this is
3103  * done in the decoding phase.
3104  */
3105 static nfsd4_enc nfsd4_enc_ops[] = {
3106 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
3107 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
3108 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
3109 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
3110 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
3111 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
3112 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
3113 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
3114 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
3115 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
3116 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
3117 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
3118 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
3119 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
3120 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
3121 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
3122 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
3123 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
3124 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
3125 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
3126 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
3127 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
3128 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
3129 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
3130 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
3131 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
3132 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
3133 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
3134 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
3135 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
3136 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
3137 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
3138 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
3139 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
3140 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
3141 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
3142 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
3143 
3144 	/* NFSv4.1 operations */
3145 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
3146 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_noop,
3147 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
3148 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
3149 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_destroy_session,
3150 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
3151 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
3152 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
3153 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
3154 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
3155 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
3156 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
3157 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_noop,
3158 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
3159 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
3160 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
3161 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
3162 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
3163 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
3164 };
3165 
3166 /*
3167  * Calculate the total amount of memory that the compound response has taken
3168  * after encoding the current operation.
3169  *
3170  * pad: add on 8 bytes for the next operation's op_code and status so that
3171  * there is room to cache a failure on the next operation.
3172  *
3173  * Compare this length to the session se_fmaxresp_cached.
3174  *
3175  * Our se_fmaxresp_cached will always be a multiple of PAGE_SIZE, and so
3176  * will be at least a page and will therefore hold the xdr_buf head.
3177  */
3178 static int nfsd4_check_drc_limit(struct nfsd4_compoundres *resp)
3179 {
3180 	int status = 0;
3181 	struct xdr_buf *xb = &resp->rqstp->rq_res;
3182 	struct nfsd4_compoundargs *args = resp->rqstp->rq_argp;
3183 	struct nfsd4_session *session = NULL;
3184 	struct nfsd4_slot *slot = resp->cstate.slot;
3185 	u32 length, tlen = 0, pad = 8;
3186 
3187 	if (!nfsd4_has_session(&resp->cstate))
3188 		return status;
3189 
3190 	session = resp->cstate.session;
3191 	if (session == NULL || slot->sl_cachethis == 0)
3192 		return status;
3193 
3194 	if (resp->opcnt >= args->opcnt)
3195 		pad = 0; /* this is the last operation */
3196 
3197 	if (xb->page_len == 0) {
3198 		length = (char *)resp->p - (char *)xb->head[0].iov_base + pad;
3199 	} else {
3200 		if (xb->tail[0].iov_base && xb->tail[0].iov_len > 0)
3201 			tlen = (char *)resp->p - (char *)xb->tail[0].iov_base;
3202 
3203 		length = xb->head[0].iov_len + xb->page_len + tlen + pad;
3204 	}
3205 	dprintk("%s length %u, xb->page_len %u tlen %u pad %u\n", __func__,
3206 		length, xb->page_len, tlen, pad);
3207 
3208 	if (length <= session->se_fchannel.maxresp_cached)
3209 		return status;
3210 	else
3211 		return nfserr_rep_too_big_to_cache;
3212 }
3213 
3214 void
3215 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
3216 {
3217 	__be32 *statp;
3218 	__be32 *p;
3219 
3220 	RESERVE_SPACE(8);
3221 	WRITE32(op->opnum);
3222 	statp = p++;	/* to be backfilled at the end */
3223 	ADJUST_ARGS();
3224 
3225 	if (op->opnum == OP_ILLEGAL)
3226 		goto status;
3227 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
3228 	       !nfsd4_enc_ops[op->opnum]);
3229 	op->status = nfsd4_enc_ops[op->opnum](resp, op->status, &op->u);
3230 	/* nfsd4_check_drc_limit guarantees enough room for error status */
3231 	if (!op->status && nfsd4_check_drc_limit(resp))
3232 		op->status = nfserr_rep_too_big_to_cache;
3233 status:
3234 	/*
3235 	 * Note: We write the status directly, instead of using WRITE32(),
3236 	 * since it is already in network byte order.
3237 	 */
3238 	*statp = op->status;
3239 }
3240 
3241 /*
3242  * Encode the reply stored in the stateowner reply cache
3243  *
3244  * XDR note: do not encode rp->rp_buflen: the buffer contains the
3245  * previously sent already encoded operation.
3246  *
3247  * called with nfs4_lock_state() held
3248  */
3249 void
3250 nfsd4_encode_replay(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
3251 {
3252 	__be32 *p;
3253 	struct nfs4_replay *rp = op->replay;
3254 
3255 	BUG_ON(!rp);
3256 
3257 	RESERVE_SPACE(8);
3258 	WRITE32(op->opnum);
3259 	*p++ = rp->rp_status;  /* already xdr'ed */
3260 	ADJUST_ARGS();
3261 
3262 	RESERVE_SPACE(rp->rp_buflen);
3263 	WRITEMEM(rp->rp_buf, rp->rp_buflen);
3264 	ADJUST_ARGS();
3265 }
3266 
3267 int
3268 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
3269 {
3270         return xdr_ressize_check(rqstp, p);
3271 }
3272 
3273 void nfsd4_release_compoundargs(struct nfsd4_compoundargs *args)
3274 {
3275 	if (args->ops != args->iops) {
3276 		kfree(args->ops);
3277 		args->ops = args->iops;
3278 	}
3279 	kfree(args->tmpp);
3280 	args->tmpp = NULL;
3281 	while (args->to_free) {
3282 		struct tmpbuf *tb = args->to_free;
3283 		args->to_free = tb->next;
3284 		tb->release(tb->buf);
3285 		kfree(tb);
3286 	}
3287 }
3288 
3289 int
3290 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundargs *args)
3291 {
3292 	__be32 status;
3293 
3294 	args->p = p;
3295 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
3296 	args->pagelist = rqstp->rq_arg.pages;
3297 	args->pagelen = rqstp->rq_arg.page_len;
3298 	args->tmpp = NULL;
3299 	args->to_free = NULL;
3300 	args->ops = args->iops;
3301 	args->rqstp = rqstp;
3302 
3303 	status = nfsd4_decode_compound(args);
3304 	if (status) {
3305 		nfsd4_release_compoundargs(args);
3306 	}
3307 	return !status;
3308 }
3309 
3310 int
3311 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundres *resp)
3312 {
3313 	/*
3314 	 * All that remains is to write the tag and operation count...
3315 	 */
3316 	struct nfsd4_compound_state *cs = &resp->cstate;
3317 	struct kvec *iov;
3318 	p = resp->tagp;
3319 	*p++ = htonl(resp->taglen);
3320 	memcpy(p, resp->tag, resp->taglen);
3321 	p += XDR_QUADLEN(resp->taglen);
3322 	*p++ = htonl(resp->opcnt);
3323 
3324 	if (rqstp->rq_res.page_len)
3325 		iov = &rqstp->rq_res.tail[0];
3326 	else
3327 		iov = &rqstp->rq_res.head[0];
3328 	iov->iov_len = ((char*)resp->p) - (char*)iov->iov_base;
3329 	BUG_ON(iov->iov_len > PAGE_SIZE);
3330 	if (nfsd4_has_session(cs)) {
3331 		if (cs->status != nfserr_replay_cache) {
3332 			nfsd4_store_cache_entry(resp);
3333 			dprintk("%s: SET SLOT STATE TO AVAILABLE\n", __func__);
3334 			cs->slot->sl_inuse = false;
3335 		}
3336 		/* Renew the clientid on success and on replay */
3337 		release_session_client(cs->session);
3338 		nfsd4_put_session(cs->session);
3339 	}
3340 	return 1;
3341 }
3342 
3343 /*
3344  * Local variables:
3345  *  c-basic-offset: 8
3346  * End:
3347  */
3348