xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision 54525552)
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/sunrpc/svcauth_gss.h>
48 
49 #include "idmap.h"
50 #include "acl.h"
51 #include "xdr4.h"
52 #include "vfs.h"
53 
54 
55 #define NFSDDBG_FACILITY		NFSDDBG_XDR
56 
57 /*
58  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
59  * directory in order to indicate to the client that a filesystem boundary is present
60  * We use a fixed fsid for a referral
61  */
62 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
63 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
64 
65 static __be32
66 check_filename(char *str, int len, __be32 err)
67 {
68 	int i;
69 
70 	if (len == 0)
71 		return nfserr_inval;
72 	if (isdotent(str, len))
73 		return err;
74 	for (i = 0; i < len; i++)
75 		if (str[i] == '/')
76 			return err;
77 	return 0;
78 }
79 
80 #define DECODE_HEAD				\
81 	__be32 *p;				\
82 	__be32 status
83 #define DECODE_TAIL				\
84 	status = 0;				\
85 out:						\
86 	return status;				\
87 xdr_error:					\
88 	dprintk("NFSD: xdr error (%s:%d)\n",	\
89 			__FILE__, __LINE__);	\
90 	status = nfserr_bad_xdr;		\
91 	goto out
92 
93 #define READ32(x)         (x) = ntohl(*p++)
94 #define READ64(x)         do {			\
95 	(x) = (u64)ntohl(*p++) << 32;		\
96 	(x) |= ntohl(*p++);			\
97 } while (0)
98 #define READTIME(x)       do {			\
99 	p++;					\
100 	(x) = ntohl(*p++);			\
101 	p++;					\
102 } while (0)
103 #define READMEM(x,nbytes) do {			\
104 	x = (char *)p;				\
105 	p += XDR_QUADLEN(nbytes);		\
106 } while (0)
107 #define SAVEMEM(x,nbytes) do {			\
108 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
109  		savemem(argp, p, nbytes) :	\
110  		(char *)p)) {			\
111 		dprintk("NFSD: xdr error (%s:%d)\n", \
112 				__FILE__, __LINE__); \
113 		goto xdr_error;			\
114 		}				\
115 	p += XDR_QUADLEN(nbytes);		\
116 } while (0)
117 #define COPYMEM(x,nbytes) do {			\
118 	memcpy((x), p, nbytes);			\
119 	p += XDR_QUADLEN(nbytes);		\
120 } while (0)
121 
122 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
123 #define READ_BUF(nbytes)  do {			\
124 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
125 		p = argp->p;			\
126 		argp->p += XDR_QUADLEN(nbytes);	\
127 	} else if (!(p = read_buf(argp, nbytes))) { \
128 		dprintk("NFSD: xdr error (%s:%d)\n", \
129 				__FILE__, __LINE__); \
130 		goto xdr_error;			\
131 	}					\
132 } while (0)
133 
134 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
135 {
136 	/* We want more bytes than seem to be available.
137 	 * Maybe we need a new page, maybe we have just run out
138 	 */
139 	unsigned int avail = (char *)argp->end - (char *)argp->p;
140 	__be32 *p;
141 	if (avail + argp->pagelen < nbytes)
142 		return NULL;
143 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
144 		return NULL;
145 	/* ok, we can do it with the current plus the next page */
146 	if (nbytes <= sizeof(argp->tmp))
147 		p = argp->tmp;
148 	else {
149 		kfree(argp->tmpp);
150 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
151 		if (!p)
152 			return NULL;
153 
154 	}
155 	/*
156 	 * The following memcpy is safe because read_buf is always
157 	 * called with nbytes > avail, and the two cases above both
158 	 * guarantee p points to at least nbytes bytes.
159 	 */
160 	memcpy(p, argp->p, avail);
161 	/* step to next page */
162 	argp->p = page_address(argp->pagelist[0]);
163 	argp->pagelist++;
164 	if (argp->pagelen < PAGE_SIZE) {
165 		argp->end = argp->p + (argp->pagelen>>2);
166 		argp->pagelen = 0;
167 	} else {
168 		argp->end = argp->p + (PAGE_SIZE>>2);
169 		argp->pagelen -= PAGE_SIZE;
170 	}
171 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
172 	argp->p += XDR_QUADLEN(nbytes - avail);
173 	return p;
174 }
175 
176 static int zero_clientid(clientid_t *clid)
177 {
178 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
179 }
180 
181 static int
182 defer_free(struct nfsd4_compoundargs *argp,
183 		void (*release)(const void *), void *p)
184 {
185 	struct tmpbuf *tb;
186 
187 	tb = kmalloc(sizeof(*tb), GFP_KERNEL);
188 	if (!tb)
189 		return -ENOMEM;
190 	tb->buf = p;
191 	tb->release = release;
192 	tb->next = argp->to_free;
193 	argp->to_free = tb;
194 	return 0;
195 }
196 
197 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
198 {
199 	if (p == argp->tmp) {
200 		p = kmalloc(nbytes, GFP_KERNEL);
201 		if (!p)
202 			return NULL;
203 		memcpy(p, argp->tmp, nbytes);
204 	} else {
205 		BUG_ON(p != argp->tmpp);
206 		argp->tmpp = NULL;
207 	}
208 	if (defer_free(argp, kfree, p)) {
209 		kfree(p);
210 		return NULL;
211 	} else
212 		return (char *)p;
213 }
214 
215 static __be32
216 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
217 {
218 	u32 bmlen;
219 	DECODE_HEAD;
220 
221 	bmval[0] = 0;
222 	bmval[1] = 0;
223 	bmval[2] = 0;
224 
225 	READ_BUF(4);
226 	READ32(bmlen);
227 	if (bmlen > 1000)
228 		goto xdr_error;
229 
230 	READ_BUF(bmlen << 2);
231 	if (bmlen > 0)
232 		READ32(bmval[0]);
233 	if (bmlen > 1)
234 		READ32(bmval[1]);
235 	if (bmlen > 2)
236 		READ32(bmval[2]);
237 
238 	DECODE_TAIL;
239 }
240 
241 static __be32
242 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
243 		   struct iattr *iattr, struct nfs4_acl **acl)
244 {
245 	int expected_len, len = 0;
246 	u32 dummy32;
247 	char *buf;
248 	int host_err;
249 
250 	DECODE_HEAD;
251 	iattr->ia_valid = 0;
252 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
253 		return status;
254 
255 	READ_BUF(4);
256 	READ32(expected_len);
257 
258 	if (bmval[0] & FATTR4_WORD0_SIZE) {
259 		READ_BUF(8);
260 		len += 8;
261 		READ64(iattr->ia_size);
262 		iattr->ia_valid |= ATTR_SIZE;
263 	}
264 	if (bmval[0] & FATTR4_WORD0_ACL) {
265 		int nace;
266 		struct nfs4_ace *ace;
267 
268 		READ_BUF(4); len += 4;
269 		READ32(nace);
270 
271 		if (nace > NFS4_ACL_MAX)
272 			return nfserr_resource;
273 
274 		*acl = nfs4_acl_new(nace);
275 		if (*acl == NULL) {
276 			host_err = -ENOMEM;
277 			goto out_nfserr;
278 		}
279 		defer_free(argp, kfree, *acl);
280 
281 		(*acl)->naces = nace;
282 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
283 			READ_BUF(16); len += 16;
284 			READ32(ace->type);
285 			READ32(ace->flag);
286 			READ32(ace->access_mask);
287 			READ32(dummy32);
288 			READ_BUF(dummy32);
289 			len += XDR_QUADLEN(dummy32) << 2;
290 			READMEM(buf, dummy32);
291 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
292 			status = nfs_ok;
293 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
294 				ace->who = 0;
295 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
296 				status = nfsd_map_name_to_gid(argp->rqstp,
297 						buf, dummy32, &ace->who);
298 			else
299 				status = nfsd_map_name_to_uid(argp->rqstp,
300 						buf, dummy32, &ace->who);
301 			if (status)
302 				return status;
303 		}
304 	} else
305 		*acl = NULL;
306 	if (bmval[1] & FATTR4_WORD1_MODE) {
307 		READ_BUF(4);
308 		len += 4;
309 		READ32(iattr->ia_mode);
310 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
311 		iattr->ia_valid |= ATTR_MODE;
312 	}
313 	if (bmval[1] & FATTR4_WORD1_OWNER) {
314 		READ_BUF(4);
315 		len += 4;
316 		READ32(dummy32);
317 		READ_BUF(dummy32);
318 		len += (XDR_QUADLEN(dummy32) << 2);
319 		READMEM(buf, dummy32);
320 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
321 			return status;
322 		iattr->ia_valid |= ATTR_UID;
323 	}
324 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
325 		READ_BUF(4);
326 		len += 4;
327 		READ32(dummy32);
328 		READ_BUF(dummy32);
329 		len += (XDR_QUADLEN(dummy32) << 2);
330 		READMEM(buf, dummy32);
331 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
332 			return status;
333 		iattr->ia_valid |= ATTR_GID;
334 	}
335 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
336 		READ_BUF(4);
337 		len += 4;
338 		READ32(dummy32);
339 		switch (dummy32) {
340 		case NFS4_SET_TO_CLIENT_TIME:
341 			/* We require the high 32 bits of 'seconds' to be 0, and we ignore
342 			   all 32 bits of 'nseconds'. */
343 			READ_BUF(12);
344 			len += 12;
345 			READ32(dummy32);
346 			if (dummy32)
347 				return nfserr_inval;
348 			READ32(iattr->ia_atime.tv_sec);
349 			READ32(iattr->ia_atime.tv_nsec);
350 			if (iattr->ia_atime.tv_nsec >= (u32)1000000000)
351 				return nfserr_inval;
352 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
353 			break;
354 		case NFS4_SET_TO_SERVER_TIME:
355 			iattr->ia_valid |= ATTR_ATIME;
356 			break;
357 		default:
358 			goto xdr_error;
359 		}
360 	}
361 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
362 		READ_BUF(4);
363 		len += 4;
364 		READ32(dummy32);
365 		switch (dummy32) {
366 		case NFS4_SET_TO_CLIENT_TIME:
367 			/* We require the high 32 bits of 'seconds' to be 0, and we ignore
368 			   all 32 bits of 'nseconds'. */
369 			READ_BUF(12);
370 			len += 12;
371 			READ32(dummy32);
372 			if (dummy32)
373 				return nfserr_inval;
374 			READ32(iattr->ia_mtime.tv_sec);
375 			READ32(iattr->ia_mtime.tv_nsec);
376 			if (iattr->ia_mtime.tv_nsec >= (u32)1000000000)
377 				return nfserr_inval;
378 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
379 			break;
380 		case NFS4_SET_TO_SERVER_TIME:
381 			iattr->ia_valid |= ATTR_MTIME;
382 			break;
383 		default:
384 			goto xdr_error;
385 		}
386 	}
387 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
388 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
389 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2)
390 		READ_BUF(expected_len - len);
391 	else if (len != expected_len)
392 		goto xdr_error;
393 
394 	DECODE_TAIL;
395 
396 out_nfserr:
397 	status = nfserrno(host_err);
398 	goto out;
399 }
400 
401 static __be32
402 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
403 {
404 	DECODE_HEAD;
405 
406 	READ_BUF(sizeof(stateid_t));
407 	READ32(sid->si_generation);
408 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
409 
410 	DECODE_TAIL;
411 }
412 
413 static __be32
414 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
415 {
416 	DECODE_HEAD;
417 
418 	READ_BUF(4);
419 	READ32(access->ac_req_access);
420 
421 	DECODE_TAIL;
422 }
423 
424 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
425 {
426 	DECODE_HEAD;
427 	u32 dummy;
428 
429 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
430 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
431 	READ32(bcts->dir);
432 	/* XXX: Perhaps Tom Tucker could help us figure out how we
433 	 * should be using ctsa_use_conn_in_rdma_mode: */
434 	READ32(dummy);
435 
436 	DECODE_TAIL;
437 }
438 
439 static __be32
440 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
441 {
442 	DECODE_HEAD;
443 
444 	close->cl_stateowner = NULL;
445 	READ_BUF(4);
446 	READ32(close->cl_seqid);
447 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
448 
449 	DECODE_TAIL;
450 }
451 
452 
453 static __be32
454 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
455 {
456 	DECODE_HEAD;
457 
458 	READ_BUF(12);
459 	READ64(commit->co_offset);
460 	READ32(commit->co_count);
461 
462 	DECODE_TAIL;
463 }
464 
465 static __be32
466 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
467 {
468 	DECODE_HEAD;
469 
470 	READ_BUF(4);
471 	READ32(create->cr_type);
472 	switch (create->cr_type) {
473 	case NF4LNK:
474 		READ_BUF(4);
475 		READ32(create->cr_linklen);
476 		READ_BUF(create->cr_linklen);
477 		SAVEMEM(create->cr_linkname, create->cr_linklen);
478 		break;
479 	case NF4BLK:
480 	case NF4CHR:
481 		READ_BUF(8);
482 		READ32(create->cr_specdata1);
483 		READ32(create->cr_specdata2);
484 		break;
485 	case NF4SOCK:
486 	case NF4FIFO:
487 	case NF4DIR:
488 	default:
489 		break;
490 	}
491 
492 	READ_BUF(4);
493 	READ32(create->cr_namelen);
494 	READ_BUF(create->cr_namelen);
495 	SAVEMEM(create->cr_name, create->cr_namelen);
496 	if ((status = check_filename(create->cr_name, create->cr_namelen, nfserr_inval)))
497 		return status;
498 
499 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
500 				    &create->cr_acl);
501 	if (status)
502 		goto out;
503 
504 	DECODE_TAIL;
505 }
506 
507 static inline __be32
508 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
509 {
510 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
511 }
512 
513 static inline __be32
514 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
515 {
516 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
517 }
518 
519 static __be32
520 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
521 {
522 	DECODE_HEAD;
523 
524 	READ_BUF(4);
525 	READ32(link->li_namelen);
526 	READ_BUF(link->li_namelen);
527 	SAVEMEM(link->li_name, link->li_namelen);
528 	if ((status = check_filename(link->li_name, link->li_namelen, nfserr_inval)))
529 		return status;
530 
531 	DECODE_TAIL;
532 }
533 
534 static __be32
535 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
536 {
537 	DECODE_HEAD;
538 
539 	lock->lk_replay_owner = NULL;
540 	/*
541 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
542 	*/
543 	READ_BUF(28);
544 	READ32(lock->lk_type);
545 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
546 		goto xdr_error;
547 	READ32(lock->lk_reclaim);
548 	READ64(lock->lk_offset);
549 	READ64(lock->lk_length);
550 	READ32(lock->lk_is_new);
551 
552 	if (lock->lk_is_new) {
553 		READ_BUF(4);
554 		READ32(lock->lk_new_open_seqid);
555 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
556 		if (status)
557 			return status;
558 		READ_BUF(8 + sizeof(clientid_t));
559 		READ32(lock->lk_new_lock_seqid);
560 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
561 		READ32(lock->lk_new_owner.len);
562 		READ_BUF(lock->lk_new_owner.len);
563 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
564 	} else {
565 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
566 		if (status)
567 			return status;
568 		READ_BUF(4);
569 		READ32(lock->lk_old_lock_seqid);
570 	}
571 
572 	DECODE_TAIL;
573 }
574 
575 static __be32
576 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
577 {
578 	DECODE_HEAD;
579 
580 	READ_BUF(32);
581 	READ32(lockt->lt_type);
582 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
583 		goto xdr_error;
584 	READ64(lockt->lt_offset);
585 	READ64(lockt->lt_length);
586 	COPYMEM(&lockt->lt_clientid, 8);
587 	READ32(lockt->lt_owner.len);
588 	READ_BUF(lockt->lt_owner.len);
589 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
590 
591 	if (argp->minorversion && !zero_clientid(&lockt->lt_clientid))
592 		return nfserr_inval;
593 	DECODE_TAIL;
594 }
595 
596 static __be32
597 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
598 {
599 	DECODE_HEAD;
600 
601 	locku->lu_stateowner = NULL;
602 	READ_BUF(8);
603 	READ32(locku->lu_type);
604 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
605 		goto xdr_error;
606 	READ32(locku->lu_seqid);
607 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
608 	if (status)
609 		return status;
610 	READ_BUF(16);
611 	READ64(locku->lu_offset);
612 	READ64(locku->lu_length);
613 
614 	DECODE_TAIL;
615 }
616 
617 static __be32
618 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
619 {
620 	DECODE_HEAD;
621 
622 	READ_BUF(4);
623 	READ32(lookup->lo_len);
624 	READ_BUF(lookup->lo_len);
625 	SAVEMEM(lookup->lo_name, lookup->lo_len);
626 	if ((status = check_filename(lookup->lo_name, lookup->lo_len, nfserr_noent)))
627 		return status;
628 
629 	DECODE_TAIL;
630 }
631 
632 static __be32
633 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
634 {
635 	DECODE_HEAD;
636 
637 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
638 	open->op_iattr.ia_valid = 0;
639 	open->op_stateowner = NULL;
640 
641 	/* seqid, share_access, share_deny, clientid, ownerlen */
642 	READ_BUF(16 + sizeof(clientid_t));
643 	READ32(open->op_seqid);
644 	READ32(open->op_share_access);
645 	READ32(open->op_share_deny);
646 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
647 	READ32(open->op_owner.len);
648 
649 	/* owner, open_flag */
650 	READ_BUF(open->op_owner.len + 4);
651 	SAVEMEM(open->op_owner.data, open->op_owner.len);
652 	READ32(open->op_create);
653 	switch (open->op_create) {
654 	case NFS4_OPEN_NOCREATE:
655 		break;
656 	case NFS4_OPEN_CREATE:
657 		READ_BUF(4);
658 		READ32(open->op_createmode);
659 		switch (open->op_createmode) {
660 		case NFS4_CREATE_UNCHECKED:
661 		case NFS4_CREATE_GUARDED:
662 			status = nfsd4_decode_fattr(argp, open->op_bmval,
663 				&open->op_iattr, &open->op_acl);
664 			if (status)
665 				goto out;
666 			break;
667 		case NFS4_CREATE_EXCLUSIVE:
668 			READ_BUF(8);
669 			COPYMEM(open->op_verf.data, 8);
670 			break;
671 		case NFS4_CREATE_EXCLUSIVE4_1:
672 			if (argp->minorversion < 1)
673 				goto xdr_error;
674 			READ_BUF(8);
675 			COPYMEM(open->op_verf.data, 8);
676 			status = nfsd4_decode_fattr(argp, open->op_bmval,
677 				&open->op_iattr, &open->op_acl);
678 			if (status)
679 				goto out;
680 			break;
681 		default:
682 			goto xdr_error;
683 		}
684 		break;
685 	default:
686 		goto xdr_error;
687 	}
688 
689 	/* open_claim */
690 	READ_BUF(4);
691 	READ32(open->op_claim_type);
692 	switch (open->op_claim_type) {
693 	case NFS4_OPEN_CLAIM_NULL:
694 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
695 		READ_BUF(4);
696 		READ32(open->op_fname.len);
697 		READ_BUF(open->op_fname.len);
698 		SAVEMEM(open->op_fname.data, open->op_fname.len);
699 		if ((status = check_filename(open->op_fname.data, open->op_fname.len, nfserr_inval)))
700 			return status;
701 		break;
702 	case NFS4_OPEN_CLAIM_PREVIOUS:
703 		READ_BUF(4);
704 		READ32(open->op_delegate_type);
705 		break;
706 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
707 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
708 		if (status)
709 			return status;
710 		READ_BUF(4);
711 		READ32(open->op_fname.len);
712 		READ_BUF(open->op_fname.len);
713 		SAVEMEM(open->op_fname.data, open->op_fname.len);
714 		if ((status = check_filename(open->op_fname.data, open->op_fname.len, nfserr_inval)))
715 			return status;
716 		break;
717 	default:
718 		goto xdr_error;
719 	}
720 
721 	DECODE_TAIL;
722 }
723 
724 static __be32
725 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
726 {
727 	DECODE_HEAD;
728 
729 	open_conf->oc_stateowner = NULL;
730 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
731 	if (status)
732 		return status;
733 	READ_BUF(4);
734 	READ32(open_conf->oc_seqid);
735 
736 	DECODE_TAIL;
737 }
738 
739 static __be32
740 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
741 {
742 	DECODE_HEAD;
743 
744 	open_down->od_stateowner = NULL;
745 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
746 	if (status)
747 		return status;
748 	READ_BUF(12);
749 	READ32(open_down->od_seqid);
750 	READ32(open_down->od_share_access);
751 	READ32(open_down->od_share_deny);
752 
753 	DECODE_TAIL;
754 }
755 
756 static __be32
757 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
758 {
759 	DECODE_HEAD;
760 
761 	READ_BUF(4);
762 	READ32(putfh->pf_fhlen);
763 	if (putfh->pf_fhlen > NFS4_FHSIZE)
764 		goto xdr_error;
765 	READ_BUF(putfh->pf_fhlen);
766 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
767 
768 	DECODE_TAIL;
769 }
770 
771 static __be32
772 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
773 {
774 	DECODE_HEAD;
775 
776 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
777 	if (status)
778 		return status;
779 	READ_BUF(12);
780 	READ64(read->rd_offset);
781 	READ32(read->rd_length);
782 
783 	DECODE_TAIL;
784 }
785 
786 static __be32
787 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
788 {
789 	DECODE_HEAD;
790 
791 	READ_BUF(24);
792 	READ64(readdir->rd_cookie);
793 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
794 	READ32(readdir->rd_dircount);    /* just in case you needed a useless field... */
795 	READ32(readdir->rd_maxcount);
796 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
797 		goto out;
798 
799 	DECODE_TAIL;
800 }
801 
802 static __be32
803 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
804 {
805 	DECODE_HEAD;
806 
807 	READ_BUF(4);
808 	READ32(remove->rm_namelen);
809 	READ_BUF(remove->rm_namelen);
810 	SAVEMEM(remove->rm_name, remove->rm_namelen);
811 	if ((status = check_filename(remove->rm_name, remove->rm_namelen, nfserr_noent)))
812 		return status;
813 
814 	DECODE_TAIL;
815 }
816 
817 static __be32
818 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
819 {
820 	DECODE_HEAD;
821 
822 	READ_BUF(4);
823 	READ32(rename->rn_snamelen);
824 	READ_BUF(rename->rn_snamelen + 4);
825 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
826 	READ32(rename->rn_tnamelen);
827 	READ_BUF(rename->rn_tnamelen);
828 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
829 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen, nfserr_noent)))
830 		return status;
831 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen, nfserr_inval)))
832 		return status;
833 
834 	DECODE_TAIL;
835 }
836 
837 static __be32
838 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
839 {
840 	DECODE_HEAD;
841 
842 	READ_BUF(sizeof(clientid_t));
843 	COPYMEM(clientid, sizeof(clientid_t));
844 
845 	DECODE_TAIL;
846 }
847 
848 static __be32
849 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
850 		     struct nfsd4_secinfo *secinfo)
851 {
852 	DECODE_HEAD;
853 
854 	READ_BUF(4);
855 	READ32(secinfo->si_namelen);
856 	READ_BUF(secinfo->si_namelen);
857 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
858 	status = check_filename(secinfo->si_name, secinfo->si_namelen,
859 								nfserr_noent);
860 	if (status)
861 		return status;
862 	DECODE_TAIL;
863 }
864 
865 static __be32
866 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
867 		     struct nfsd4_secinfo_no_name *sin)
868 {
869 	DECODE_HEAD;
870 
871 	READ_BUF(4);
872 	READ32(sin->sin_style);
873 	DECODE_TAIL;
874 }
875 
876 static __be32
877 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
878 {
879 	__be32 status;
880 
881 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
882 	if (status)
883 		return status;
884 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
885 				  &setattr->sa_acl);
886 }
887 
888 static __be32
889 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
890 {
891 	DECODE_HEAD;
892 
893 	READ_BUF(12);
894 	COPYMEM(setclientid->se_verf.data, 8);
895 	READ32(setclientid->se_namelen);
896 
897 	READ_BUF(setclientid->se_namelen + 8);
898 	SAVEMEM(setclientid->se_name, setclientid->se_namelen);
899 	READ32(setclientid->se_callback_prog);
900 	READ32(setclientid->se_callback_netid_len);
901 
902 	READ_BUF(setclientid->se_callback_netid_len + 4);
903 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
904 	READ32(setclientid->se_callback_addr_len);
905 
906 	READ_BUF(setclientid->se_callback_addr_len + 4);
907 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
908 	READ32(setclientid->se_callback_ident);
909 
910 	DECODE_TAIL;
911 }
912 
913 static __be32
914 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
915 {
916 	DECODE_HEAD;
917 
918 	READ_BUF(8 + sizeof(nfs4_verifier));
919 	COPYMEM(&scd_c->sc_clientid, 8);
920 	COPYMEM(&scd_c->sc_confirm, sizeof(nfs4_verifier));
921 
922 	DECODE_TAIL;
923 }
924 
925 /* Also used for NVERIFY */
926 static __be32
927 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
928 {
929 #if 0
930 	struct nfsd4_compoundargs save = {
931 		.p = argp->p,
932 		.end = argp->end,
933 		.rqstp = argp->rqstp,
934 	};
935 	u32             ve_bmval[2];
936 	struct iattr    ve_iattr;           /* request */
937 	struct nfs4_acl *ve_acl;            /* request */
938 #endif
939 	DECODE_HEAD;
940 
941 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
942 		goto out;
943 
944 	/* For convenience's sake, we compare raw xdr'd attributes in
945 	 * nfsd4_proc_verify; however we still decode here just to return
946 	 * correct error in case of bad xdr. */
947 #if 0
948 	status = nfsd4_decode_fattr(ve_bmval, &ve_iattr, &ve_acl);
949 	if (status == nfserr_inval) {
950 		status = nfserrno(status);
951 		goto out;
952 	}
953 #endif
954 	READ_BUF(4);
955 	READ32(verify->ve_attrlen);
956 	READ_BUF(verify->ve_attrlen);
957 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
958 
959 	DECODE_TAIL;
960 }
961 
962 static __be32
963 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
964 {
965 	int avail;
966 	int v;
967 	int len;
968 	DECODE_HEAD;
969 
970 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
971 	if (status)
972 		return status;
973 	READ_BUF(16);
974 	READ64(write->wr_offset);
975 	READ32(write->wr_stable_how);
976 	if (write->wr_stable_how > 2)
977 		goto xdr_error;
978 	READ32(write->wr_buflen);
979 
980 	/* Sorry .. no magic macros for this.. *
981 	 * READ_BUF(write->wr_buflen);
982 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
983 	 */
984 	avail = (char*)argp->end - (char*)argp->p;
985 	if (avail + argp->pagelen < write->wr_buflen) {
986 		dprintk("NFSD: xdr error (%s:%d)\n",
987 				__FILE__, __LINE__);
988 		goto xdr_error;
989 	}
990 	argp->rqstp->rq_vec[0].iov_base = p;
991 	argp->rqstp->rq_vec[0].iov_len = avail;
992 	v = 0;
993 	len = write->wr_buflen;
994 	while (len > argp->rqstp->rq_vec[v].iov_len) {
995 		len -= argp->rqstp->rq_vec[v].iov_len;
996 		v++;
997 		argp->rqstp->rq_vec[v].iov_base = page_address(argp->pagelist[0]);
998 		argp->pagelist++;
999 		if (argp->pagelen >= PAGE_SIZE) {
1000 			argp->rqstp->rq_vec[v].iov_len = PAGE_SIZE;
1001 			argp->pagelen -= PAGE_SIZE;
1002 		} else {
1003 			argp->rqstp->rq_vec[v].iov_len = argp->pagelen;
1004 			argp->pagelen -= len;
1005 		}
1006 	}
1007 	argp->end = (__be32*) (argp->rqstp->rq_vec[v].iov_base + argp->rqstp->rq_vec[v].iov_len);
1008 	argp->p = (__be32*)  (argp->rqstp->rq_vec[v].iov_base + (XDR_QUADLEN(len) << 2));
1009 	argp->rqstp->rq_vec[v].iov_len = len;
1010 	write->wr_vlen = v+1;
1011 
1012 	DECODE_TAIL;
1013 }
1014 
1015 static __be32
1016 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1017 {
1018 	DECODE_HEAD;
1019 
1020 	READ_BUF(12);
1021 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1022 	READ32(rlockowner->rl_owner.len);
1023 	READ_BUF(rlockowner->rl_owner.len);
1024 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1025 
1026 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1027 		return nfserr_inval;
1028 	DECODE_TAIL;
1029 }
1030 
1031 static __be32
1032 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1033 			 struct nfsd4_exchange_id *exid)
1034 {
1035 	int dummy, tmp;
1036 	DECODE_HEAD;
1037 
1038 	READ_BUF(NFS4_VERIFIER_SIZE);
1039 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1040 
1041 	READ_BUF(4);
1042 	READ32(exid->clname.len);
1043 
1044 	READ_BUF(exid->clname.len);
1045 	SAVEMEM(exid->clname.data, exid->clname.len);
1046 
1047 	READ_BUF(4);
1048 	READ32(exid->flags);
1049 
1050 	/* Ignore state_protect4_a */
1051 	READ_BUF(4);
1052 	READ32(exid->spa_how);
1053 	switch (exid->spa_how) {
1054 	case SP4_NONE:
1055 		break;
1056 	case SP4_MACH_CRED:
1057 		/* spo_must_enforce */
1058 		READ_BUF(4);
1059 		READ32(dummy);
1060 		READ_BUF(dummy * 4);
1061 		p += dummy;
1062 
1063 		/* spo_must_allow */
1064 		READ_BUF(4);
1065 		READ32(dummy);
1066 		READ_BUF(dummy * 4);
1067 		p += dummy;
1068 		break;
1069 	case SP4_SSV:
1070 		/* ssp_ops */
1071 		READ_BUF(4);
1072 		READ32(dummy);
1073 		READ_BUF(dummy * 4);
1074 		p += dummy;
1075 
1076 		READ_BUF(4);
1077 		READ32(dummy);
1078 		READ_BUF(dummy * 4);
1079 		p += dummy;
1080 
1081 		/* ssp_hash_algs<> */
1082 		READ_BUF(4);
1083 		READ32(tmp);
1084 		while (tmp--) {
1085 			READ_BUF(4);
1086 			READ32(dummy);
1087 			READ_BUF(dummy);
1088 			p += XDR_QUADLEN(dummy);
1089 		}
1090 
1091 		/* ssp_encr_algs<> */
1092 		READ_BUF(4);
1093 		READ32(tmp);
1094 		while (tmp--) {
1095 			READ_BUF(4);
1096 			READ32(dummy);
1097 			READ_BUF(dummy);
1098 			p += XDR_QUADLEN(dummy);
1099 		}
1100 
1101 		/* ssp_window and ssp_num_gss_handles */
1102 		READ_BUF(8);
1103 		READ32(dummy);
1104 		READ32(dummy);
1105 		break;
1106 	default:
1107 		goto xdr_error;
1108 	}
1109 
1110 	/* Ignore Implementation ID */
1111 	READ_BUF(4);    /* nfs_impl_id4 array length */
1112 	READ32(dummy);
1113 
1114 	if (dummy > 1)
1115 		goto xdr_error;
1116 
1117 	if (dummy == 1) {
1118 		/* nii_domain */
1119 		READ_BUF(4);
1120 		READ32(dummy);
1121 		READ_BUF(dummy);
1122 		p += XDR_QUADLEN(dummy);
1123 
1124 		/* nii_name */
1125 		READ_BUF(4);
1126 		READ32(dummy);
1127 		READ_BUF(dummy);
1128 		p += XDR_QUADLEN(dummy);
1129 
1130 		/* nii_date */
1131 		READ_BUF(12);
1132 		p += 3;
1133 	}
1134 	DECODE_TAIL;
1135 }
1136 
1137 static __be32
1138 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1139 			    struct nfsd4_create_session *sess)
1140 {
1141 	DECODE_HEAD;
1142 
1143 	u32 dummy;
1144 	char *machine_name;
1145 	int i;
1146 	int nr_secflavs;
1147 
1148 	READ_BUF(16);
1149 	COPYMEM(&sess->clientid, 8);
1150 	READ32(sess->seqid);
1151 	READ32(sess->flags);
1152 
1153 	/* Fore channel attrs */
1154 	READ_BUF(28);
1155 	READ32(dummy); /* headerpadsz is always 0 */
1156 	READ32(sess->fore_channel.maxreq_sz);
1157 	READ32(sess->fore_channel.maxresp_sz);
1158 	READ32(sess->fore_channel.maxresp_cached);
1159 	READ32(sess->fore_channel.maxops);
1160 	READ32(sess->fore_channel.maxreqs);
1161 	READ32(sess->fore_channel.nr_rdma_attrs);
1162 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1163 		READ_BUF(4);
1164 		READ32(sess->fore_channel.rdma_attrs);
1165 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1166 		dprintk("Too many fore channel attr bitmaps!\n");
1167 		goto xdr_error;
1168 	}
1169 
1170 	/* Back channel attrs */
1171 	READ_BUF(28);
1172 	READ32(dummy); /* headerpadsz is always 0 */
1173 	READ32(sess->back_channel.maxreq_sz);
1174 	READ32(sess->back_channel.maxresp_sz);
1175 	READ32(sess->back_channel.maxresp_cached);
1176 	READ32(sess->back_channel.maxops);
1177 	READ32(sess->back_channel.maxreqs);
1178 	READ32(sess->back_channel.nr_rdma_attrs);
1179 	if (sess->back_channel.nr_rdma_attrs == 1) {
1180 		READ_BUF(4);
1181 		READ32(sess->back_channel.rdma_attrs);
1182 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1183 		dprintk("Too many back channel attr bitmaps!\n");
1184 		goto xdr_error;
1185 	}
1186 
1187 	READ_BUF(8);
1188 	READ32(sess->callback_prog);
1189 
1190 	/* callback_sec_params4 */
1191 	READ32(nr_secflavs);
1192 	for (i = 0; i < nr_secflavs; ++i) {
1193 		READ_BUF(4);
1194 		READ32(dummy);
1195 		switch (dummy) {
1196 		case RPC_AUTH_NULL:
1197 			/* Nothing to read */
1198 			break;
1199 		case RPC_AUTH_UNIX:
1200 			READ_BUF(8);
1201 			/* stamp */
1202 			READ32(dummy);
1203 
1204 			/* machine name */
1205 			READ32(dummy);
1206 			READ_BUF(dummy);
1207 			SAVEMEM(machine_name, dummy);
1208 
1209 			/* uid, gid */
1210 			READ_BUF(8);
1211 			READ32(sess->uid);
1212 			READ32(sess->gid);
1213 
1214 			/* more gids */
1215 			READ_BUF(4);
1216 			READ32(dummy);
1217 			READ_BUF(dummy * 4);
1218 			break;
1219 		case RPC_AUTH_GSS:
1220 			dprintk("RPC_AUTH_GSS callback secflavor "
1221 				"not supported!\n");
1222 			READ_BUF(8);
1223 			/* gcbp_service */
1224 			READ32(dummy);
1225 			/* gcbp_handle_from_server */
1226 			READ32(dummy);
1227 			READ_BUF(dummy);
1228 			p += XDR_QUADLEN(dummy);
1229 			/* gcbp_handle_from_client */
1230 			READ_BUF(4);
1231 			READ32(dummy);
1232 			READ_BUF(dummy);
1233 			break;
1234 		default:
1235 			dprintk("Illegal callback secflavor\n");
1236 			return nfserr_inval;
1237 		}
1238 	}
1239 	DECODE_TAIL;
1240 }
1241 
1242 static __be32
1243 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1244 			     struct nfsd4_destroy_session *destroy_session)
1245 {
1246 	DECODE_HEAD;
1247 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1248 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1249 
1250 	DECODE_TAIL;
1251 }
1252 
1253 static __be32
1254 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1255 		      struct nfsd4_sequence *seq)
1256 {
1257 	DECODE_HEAD;
1258 
1259 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1260 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1261 	READ32(seq->seqid);
1262 	READ32(seq->slotid);
1263 	READ32(seq->maxslots);
1264 	READ32(seq->cachethis);
1265 
1266 	DECODE_TAIL;
1267 }
1268 
1269 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1270 {
1271 	DECODE_HEAD;
1272 
1273 	READ_BUF(4);
1274 	READ32(rc->rca_one_fs);
1275 
1276 	DECODE_TAIL;
1277 }
1278 
1279 static __be32
1280 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1281 {
1282 	return nfs_ok;
1283 }
1284 
1285 static __be32
1286 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1287 {
1288 	return nfserr_notsupp;
1289 }
1290 
1291 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1292 
1293 static nfsd4_dec nfsd4_dec_ops[] = {
1294 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1295 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1296 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1297 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1298 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1299 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1300 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1301 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1302 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1303 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1304 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1305 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1306 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1307 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1308 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1309 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1310 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1311 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1312 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1313 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1314 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_noop,
1315 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1316 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1317 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1318 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1319 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1320 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1321 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1322 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1323 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1324 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1325 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1326 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1327 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1328 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1329 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1330 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1331 };
1332 
1333 static nfsd4_dec nfsd41_dec_ops[] = {
1334 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1335 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1336 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1337 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1338 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1339 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1340 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1341 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1342 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1343 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1344 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1345 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1346 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1347 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1348 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1349 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1350 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1351 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_notsupp,
1352 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1353 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1354 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_notsupp,
1355 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1356 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1357 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1358 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1359 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1360 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1361 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_notsupp,
1362 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1363 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1364 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1365 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1366 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_notsupp,
1367 	[OP_SETCLIENTID_CONFIRM]= (nfsd4_dec)nfsd4_decode_notsupp,
1368 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1369 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1370 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_notsupp,
1371 
1372 	/* new operations for NFSv4.1 */
1373 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_notsupp,
1374 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1375 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1376 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1377 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1378 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_notsupp,
1379 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1380 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1381 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1382 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1383 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1384 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1385 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1386 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1387 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1388 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_notsupp,
1389 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1390 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_notsupp,
1391 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1392 };
1393 
1394 struct nfsd4_minorversion_ops {
1395 	nfsd4_dec *decoders;
1396 	int nops;
1397 };
1398 
1399 static struct nfsd4_minorversion_ops nfsd4_minorversion[] = {
1400 	[0] = { nfsd4_dec_ops, ARRAY_SIZE(nfsd4_dec_ops) },
1401 	[1] = { nfsd41_dec_ops, ARRAY_SIZE(nfsd41_dec_ops) },
1402 };
1403 
1404 static __be32
1405 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1406 {
1407 	DECODE_HEAD;
1408 	struct nfsd4_op *op;
1409 	struct nfsd4_minorversion_ops *ops;
1410 	int i;
1411 
1412 	/*
1413 	 * XXX: According to spec, we should check the tag
1414 	 * for UTF-8 compliance.  I'm postponing this for
1415 	 * now because it seems that some clients do use
1416 	 * binary tags.
1417 	 */
1418 	READ_BUF(4);
1419 	READ32(argp->taglen);
1420 	READ_BUF(argp->taglen + 8);
1421 	SAVEMEM(argp->tag, argp->taglen);
1422 	READ32(argp->minorversion);
1423 	READ32(argp->opcnt);
1424 
1425 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1426 		goto xdr_error;
1427 	if (argp->opcnt > 100)
1428 		goto xdr_error;
1429 
1430 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1431 		argp->ops = kmalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1432 		if (!argp->ops) {
1433 			argp->ops = argp->iops;
1434 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1435 			goto xdr_error;
1436 		}
1437 	}
1438 
1439 	if (argp->minorversion >= ARRAY_SIZE(nfsd4_minorversion))
1440 		argp->opcnt = 0;
1441 
1442 	ops = &nfsd4_minorversion[argp->minorversion];
1443 	for (i = 0; i < argp->opcnt; i++) {
1444 		op = &argp->ops[i];
1445 		op->replay = NULL;
1446 
1447 		/*
1448 		 * We can't use READ_BUF() here because we need to handle
1449 		 * a missing opcode as an OP_WRITE + 1. So we need to check
1450 		 * to see if we're truly at the end of our buffer or if there
1451 		 * is another page we need to flip to.
1452 		 */
1453 
1454 		if (argp->p == argp->end) {
1455 			if (argp->pagelen < 4) {
1456 				/* There isn't an opcode still on the wire */
1457 				op->opnum = OP_WRITE + 1;
1458 				op->status = nfserr_bad_xdr;
1459 				argp->opcnt = i+1;
1460 				break;
1461 			}
1462 
1463 			/*
1464 			 * False alarm. We just hit a page boundary, but there
1465 			 * is still data available.  Move pointer across page
1466 			 * boundary.  *snip from READ_BUF*
1467 			 */
1468 			argp->p = page_address(argp->pagelist[0]);
1469 			argp->pagelist++;
1470 			if (argp->pagelen < PAGE_SIZE) {
1471 				argp->end = argp->p + (argp->pagelen>>2);
1472 				argp->pagelen = 0;
1473 			} else {
1474 				argp->end = argp->p + (PAGE_SIZE>>2);
1475 				argp->pagelen -= PAGE_SIZE;
1476 			}
1477 		}
1478 		op->opnum = ntohl(*argp->p++);
1479 
1480 		if (op->opnum >= FIRST_NFS4_OP && op->opnum <= LAST_NFS4_OP)
1481 			op->status = ops->decoders[op->opnum](argp, &op->u);
1482 		else {
1483 			op->opnum = OP_ILLEGAL;
1484 			op->status = nfserr_op_illegal;
1485 		}
1486 
1487 		if (op->status) {
1488 			argp->opcnt = i+1;
1489 			break;
1490 		}
1491 	}
1492 
1493 	DECODE_TAIL;
1494 }
1495 
1496 #define WRITE32(n)               *p++ = htonl(n)
1497 #define WRITE64(n)               do {				\
1498 	*p++ = htonl((u32)((n) >> 32));				\
1499 	*p++ = htonl((u32)(n));					\
1500 } while (0)
1501 #define WRITEMEM(ptr,nbytes)     do { if (nbytes > 0) {		\
1502 	*(p + XDR_QUADLEN(nbytes) -1) = 0;                      \
1503 	memcpy(p, ptr, nbytes);					\
1504 	p += XDR_QUADLEN(nbytes);				\
1505 }} while (0)
1506 
1507 static void write32(__be32 **p, u32 n)
1508 {
1509 	*(*p)++ = n;
1510 }
1511 
1512 static void write64(__be32 **p, u64 n)
1513 {
1514 	write32(p, (u32)(n >> 32));
1515 	write32(p, (u32)n);
1516 }
1517 
1518 static void write_change(__be32 **p, struct kstat *stat, struct inode *inode)
1519 {
1520 	if (IS_I_VERSION(inode)) {
1521 		write64(p, inode->i_version);
1522 	} else {
1523 		write32(p, stat->ctime.tv_sec);
1524 		write32(p, stat->ctime.tv_nsec);
1525 	}
1526 }
1527 
1528 static void write_cinfo(__be32 **p, struct nfsd4_change_info *c)
1529 {
1530 	write32(p, c->atomic);
1531 	if (c->change_supported) {
1532 		write64(p, c->before_change);
1533 		write64(p, c->after_change);
1534 	} else {
1535 		write32(p, c->before_ctime_sec);
1536 		write32(p, c->before_ctime_nsec);
1537 		write32(p, c->after_ctime_sec);
1538 		write32(p, c->after_ctime_nsec);
1539 	}
1540 }
1541 
1542 #define RESERVE_SPACE(nbytes)	do {				\
1543 	p = resp->p;						\
1544 	BUG_ON(p + XDR_QUADLEN(nbytes) > resp->end);		\
1545 } while (0)
1546 #define ADJUST_ARGS()		resp->p = p
1547 
1548 /*
1549  * Header routine to setup seqid operation replay cache
1550  */
1551 #define ENCODE_SEQID_OP_HEAD					\
1552 	__be32 *save;						\
1553 								\
1554 	save = resp->p;
1555 
1556 /*
1557  * Routine for encoding the result of a "seqid-mutating" NFSv4 operation.  This
1558  * is where sequence id's are incremented, and the replay cache is filled.
1559  * Note that we increment sequence id's here, at the last moment, so we're sure
1560  * we know whether the error to be returned is a sequence id mutating error.
1561  */
1562 
1563 #define ENCODE_SEQID_OP_TAIL(stateowner) do {			\
1564 	if (seqid_mutating_err(nfserr) && stateowner) { 	\
1565 		stateowner->so_seqid++;				\
1566 		stateowner->so_replay.rp_status = nfserr;   	\
1567 		stateowner->so_replay.rp_buflen = 		\
1568 			  (((char *)(resp)->p - (char *)save)); \
1569 		memcpy(stateowner->so_replay.rp_buf, save,      \
1570  			stateowner->so_replay.rp_buflen); 	\
1571 	} } while (0);
1572 
1573 /* Encode as an array of strings the string given with components
1574  * separated @sep.
1575  */
1576 static __be32 nfsd4_encode_components(char sep, char *components,
1577 				   __be32 **pp, int *buflen)
1578 {
1579 	__be32 *p = *pp;
1580 	__be32 *countp = p;
1581 	int strlen, count=0;
1582 	char *str, *end;
1583 
1584 	dprintk("nfsd4_encode_components(%s)\n", components);
1585 	if ((*buflen -= 4) < 0)
1586 		return nfserr_resource;
1587 	WRITE32(0); /* We will fill this in with @count later */
1588 	end = str = components;
1589 	while (*end) {
1590 		for (; *end && (*end != sep); end++)
1591 			; /* Point to end of component */
1592 		strlen = end - str;
1593 		if (strlen) {
1594 			if ((*buflen -= ((XDR_QUADLEN(strlen) << 2) + 4)) < 0)
1595 				return nfserr_resource;
1596 			WRITE32(strlen);
1597 			WRITEMEM(str, strlen);
1598 			count++;
1599 		}
1600 		else
1601 			end++;
1602 		str = end;
1603 	}
1604 	*pp = p;
1605 	p = countp;
1606 	WRITE32(count);
1607 	return 0;
1608 }
1609 
1610 /*
1611  * encode a location element of a fs_locations structure
1612  */
1613 static __be32 nfsd4_encode_fs_location4(struct nfsd4_fs_location *location,
1614 				    __be32 **pp, int *buflen)
1615 {
1616 	__be32 status;
1617 	__be32 *p = *pp;
1618 
1619 	status = nfsd4_encode_components(':', location->hosts, &p, buflen);
1620 	if (status)
1621 		return status;
1622 	status = nfsd4_encode_components('/', location->path, &p, buflen);
1623 	if (status)
1624 		return status;
1625 	*pp = p;
1626 	return 0;
1627 }
1628 
1629 /*
1630  * Return the path to an export point in the pseudo filesystem namespace
1631  * Returned string is safe to use as long as the caller holds a reference
1632  * to @exp.
1633  */
1634 static char *nfsd4_path(struct svc_rqst *rqstp, struct svc_export *exp, __be32 *stat)
1635 {
1636 	struct svc_fh tmp_fh;
1637 	char *path = NULL, *rootpath;
1638 	size_t rootlen;
1639 
1640 	fh_init(&tmp_fh, NFS4_FHSIZE);
1641 	*stat = exp_pseudoroot(rqstp, &tmp_fh);
1642 	if (*stat)
1643 		return NULL;
1644 	rootpath = tmp_fh.fh_export->ex_pathname;
1645 
1646 	path = exp->ex_pathname;
1647 
1648 	rootlen = strlen(rootpath);
1649 	if (strncmp(path, rootpath, rootlen)) {
1650 		dprintk("nfsd: fs_locations failed;"
1651 			"%s is not contained in %s\n", path, rootpath);
1652 		*stat = nfserr_notsupp;
1653 		path = NULL;
1654 		goto out;
1655 	}
1656 	path += rootlen;
1657 out:
1658 	fh_put(&tmp_fh);
1659 	return path;
1660 }
1661 
1662 /*
1663  *  encode a fs_locations structure
1664  */
1665 static __be32 nfsd4_encode_fs_locations(struct svc_rqst *rqstp,
1666 				     struct svc_export *exp,
1667 				     __be32 **pp, int *buflen)
1668 {
1669 	__be32 status;
1670 	int i;
1671 	__be32 *p = *pp;
1672 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
1673 	char *root = nfsd4_path(rqstp, exp, &status);
1674 
1675 	if (status)
1676 		return status;
1677 	status = nfsd4_encode_components('/', root, &p, buflen);
1678 	if (status)
1679 		return status;
1680 	if ((*buflen -= 4) < 0)
1681 		return nfserr_resource;
1682 	WRITE32(fslocs->locations_count);
1683 	for (i=0; i<fslocs->locations_count; i++) {
1684 		status = nfsd4_encode_fs_location4(&fslocs->locations[i],
1685 						   &p, buflen);
1686 		if (status)
1687 			return status;
1688 	}
1689 	*pp = p;
1690 	return 0;
1691 }
1692 
1693 static u32 nfs4_ftypes[16] = {
1694         NF4BAD,  NF4FIFO, NF4CHR, NF4BAD,
1695         NF4DIR,  NF4BAD,  NF4BLK, NF4BAD,
1696         NF4REG,  NF4BAD,  NF4LNK, NF4BAD,
1697         NF4SOCK, NF4BAD,  NF4LNK, NF4BAD,
1698 };
1699 
1700 static __be32
1701 nfsd4_encode_name(struct svc_rqst *rqstp, int whotype, uid_t id, int group,
1702 			__be32 **p, int *buflen)
1703 {
1704 	int status;
1705 
1706 	if (*buflen < (XDR_QUADLEN(IDMAP_NAMESZ) << 2) + 4)
1707 		return nfserr_resource;
1708 	if (whotype != NFS4_ACL_WHO_NAMED)
1709 		status = nfs4_acl_write_who(whotype, (u8 *)(*p + 1));
1710 	else if (group)
1711 		status = nfsd_map_gid_to_name(rqstp, id, (u8 *)(*p + 1));
1712 	else
1713 		status = nfsd_map_uid_to_name(rqstp, id, (u8 *)(*p + 1));
1714 	if (status < 0)
1715 		return nfserrno(status);
1716 	*p = xdr_encode_opaque(*p, NULL, status);
1717 	*buflen -= (XDR_QUADLEN(status) << 2) + 4;
1718 	BUG_ON(*buflen < 0);
1719 	return 0;
1720 }
1721 
1722 static inline __be32
1723 nfsd4_encode_user(struct svc_rqst *rqstp, uid_t uid, __be32 **p, int *buflen)
1724 {
1725 	return nfsd4_encode_name(rqstp, NFS4_ACL_WHO_NAMED, uid, 0, p, buflen);
1726 }
1727 
1728 static inline __be32
1729 nfsd4_encode_group(struct svc_rqst *rqstp, uid_t gid, __be32 **p, int *buflen)
1730 {
1731 	return nfsd4_encode_name(rqstp, NFS4_ACL_WHO_NAMED, gid, 1, p, buflen);
1732 }
1733 
1734 static inline __be32
1735 nfsd4_encode_aclname(struct svc_rqst *rqstp, int whotype, uid_t id, int group,
1736 		__be32 **p, int *buflen)
1737 {
1738 	return nfsd4_encode_name(rqstp, whotype, id, group, p, buflen);
1739 }
1740 
1741 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
1742 			      FATTR4_WORD0_RDATTR_ERROR)
1743 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
1744 
1745 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *rdattr_err)
1746 {
1747 	/* As per referral draft:  */
1748 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
1749 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
1750 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
1751 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
1752 			*rdattr_err = NFSERR_MOVED;
1753 		else
1754 			return nfserr_moved;
1755 	}
1756 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
1757 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
1758 	return 0;
1759 }
1760 
1761 /*
1762  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
1763  * ourselves.
1764  *
1765  * @countp is the buffer size in _words_; upon successful return this becomes
1766  * replaced with the number of words written.
1767  */
1768 __be32
1769 nfsd4_encode_fattr(struct svc_fh *fhp, struct svc_export *exp,
1770 		struct dentry *dentry, __be32 *buffer, int *countp, u32 *bmval,
1771 		struct svc_rqst *rqstp, int ignore_crossmnt)
1772 {
1773 	u32 bmval0 = bmval[0];
1774 	u32 bmval1 = bmval[1];
1775 	u32 bmval2 = bmval[2];
1776 	struct kstat stat;
1777 	struct svc_fh tempfh;
1778 	struct kstatfs statfs;
1779 	int buflen = *countp << 2;
1780 	__be32 *attrlenp;
1781 	u32 dummy;
1782 	u64 dummy64;
1783 	u32 rdattr_err = 0;
1784 	__be32 *p = buffer;
1785 	__be32 status;
1786 	int err;
1787 	int aclsupport = 0;
1788 	struct nfs4_acl *acl = NULL;
1789 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
1790 	u32 minorversion = resp->cstate.minorversion;
1791 	struct path path = {
1792 		.mnt	= exp->ex_path.mnt,
1793 		.dentry	= dentry,
1794 	};
1795 
1796 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
1797 	BUG_ON(bmval0 & ~nfsd_suppattrs0(minorversion));
1798 	BUG_ON(bmval1 & ~nfsd_suppattrs1(minorversion));
1799 	BUG_ON(bmval2 & ~nfsd_suppattrs2(minorversion));
1800 
1801 	if (exp->ex_fslocs.migrated) {
1802 		BUG_ON(bmval[2]);
1803 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &rdattr_err);
1804 		if (status)
1805 			goto out;
1806 	}
1807 
1808 	err = vfs_getattr(exp->ex_path.mnt, dentry, &stat);
1809 	if (err)
1810 		goto out_nfserr;
1811 	if ((bmval0 & (FATTR4_WORD0_FILES_FREE | FATTR4_WORD0_FILES_TOTAL |
1812 			FATTR4_WORD0_MAXNAME)) ||
1813 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
1814 		       FATTR4_WORD1_SPACE_TOTAL))) {
1815 		err = vfs_statfs(&path, &statfs);
1816 		if (err)
1817 			goto out_nfserr;
1818 	}
1819 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
1820 		fh_init(&tempfh, NFS4_FHSIZE);
1821 		status = fh_compose(&tempfh, exp, dentry, NULL);
1822 		if (status)
1823 			goto out;
1824 		fhp = &tempfh;
1825 	}
1826 	if (bmval0 & (FATTR4_WORD0_ACL | FATTR4_WORD0_ACLSUPPORT
1827 			| FATTR4_WORD0_SUPPORTED_ATTRS)) {
1828 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
1829 		aclsupport = (err == 0);
1830 		if (bmval0 & FATTR4_WORD0_ACL) {
1831 			if (err == -EOPNOTSUPP)
1832 				bmval0 &= ~FATTR4_WORD0_ACL;
1833 			else if (err == -EINVAL) {
1834 				status = nfserr_attrnotsupp;
1835 				goto out;
1836 			} else if (err != 0)
1837 				goto out_nfserr;
1838 		}
1839 	}
1840 
1841 	if (bmval2) {
1842 		if ((buflen -= 16) < 0)
1843 			goto out_resource;
1844 		WRITE32(3);
1845 		WRITE32(bmval0);
1846 		WRITE32(bmval1);
1847 		WRITE32(bmval2);
1848 	} else if (bmval1) {
1849 		if ((buflen -= 12) < 0)
1850 			goto out_resource;
1851 		WRITE32(2);
1852 		WRITE32(bmval0);
1853 		WRITE32(bmval1);
1854 	} else {
1855 		if ((buflen -= 8) < 0)
1856 			goto out_resource;
1857 		WRITE32(1);
1858 		WRITE32(bmval0);
1859 	}
1860 	attrlenp = p++;                /* to be backfilled later */
1861 
1862 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
1863 		u32 word0 = nfsd_suppattrs0(minorversion);
1864 		u32 word1 = nfsd_suppattrs1(minorversion);
1865 		u32 word2 = nfsd_suppattrs2(minorversion);
1866 
1867 		if (!aclsupport)
1868 			word0 &= ~FATTR4_WORD0_ACL;
1869 		if (!word2) {
1870 			if ((buflen -= 12) < 0)
1871 				goto out_resource;
1872 			WRITE32(2);
1873 			WRITE32(word0);
1874 			WRITE32(word1);
1875 		} else {
1876 			if ((buflen -= 16) < 0)
1877 				goto out_resource;
1878 			WRITE32(3);
1879 			WRITE32(word0);
1880 			WRITE32(word1);
1881 			WRITE32(word2);
1882 		}
1883 	}
1884 	if (bmval0 & FATTR4_WORD0_TYPE) {
1885 		if ((buflen -= 4) < 0)
1886 			goto out_resource;
1887 		dummy = nfs4_ftypes[(stat.mode & S_IFMT) >> 12];
1888 		if (dummy == NF4BAD)
1889 			goto out_serverfault;
1890 		WRITE32(dummy);
1891 	}
1892 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
1893 		if ((buflen -= 4) < 0)
1894 			goto out_resource;
1895 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
1896 			WRITE32(NFS4_FH_PERSISTENT);
1897 		else
1898 			WRITE32(NFS4_FH_PERSISTENT|NFS4_FH_VOL_RENAME);
1899 	}
1900 	if (bmval0 & FATTR4_WORD0_CHANGE) {
1901 		if ((buflen -= 8) < 0)
1902 			goto out_resource;
1903 		write_change(&p, &stat, dentry->d_inode);
1904 	}
1905 	if (bmval0 & FATTR4_WORD0_SIZE) {
1906 		if ((buflen -= 8) < 0)
1907 			goto out_resource;
1908 		WRITE64(stat.size);
1909 	}
1910 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
1911 		if ((buflen -= 4) < 0)
1912 			goto out_resource;
1913 		WRITE32(1);
1914 	}
1915 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
1916 		if ((buflen -= 4) < 0)
1917 			goto out_resource;
1918 		WRITE32(1);
1919 	}
1920 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
1921 		if ((buflen -= 4) < 0)
1922 			goto out_resource;
1923 		WRITE32(0);
1924 	}
1925 	if (bmval0 & FATTR4_WORD0_FSID) {
1926 		if ((buflen -= 16) < 0)
1927 			goto out_resource;
1928 		if (exp->ex_fslocs.migrated) {
1929 			WRITE64(NFS4_REFERRAL_FSID_MAJOR);
1930 			WRITE64(NFS4_REFERRAL_FSID_MINOR);
1931 		} else switch(fsid_source(fhp)) {
1932 		case FSIDSOURCE_FSID:
1933 			WRITE64((u64)exp->ex_fsid);
1934 			WRITE64((u64)0);
1935 			break;
1936 		case FSIDSOURCE_DEV:
1937 			WRITE32(0);
1938 			WRITE32(MAJOR(stat.dev));
1939 			WRITE32(0);
1940 			WRITE32(MINOR(stat.dev));
1941 			break;
1942 		case FSIDSOURCE_UUID:
1943 			WRITEMEM(exp->ex_uuid, 16);
1944 			break;
1945 		}
1946 	}
1947 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
1948 		if ((buflen -= 4) < 0)
1949 			goto out_resource;
1950 		WRITE32(0);
1951 	}
1952 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
1953 		if ((buflen -= 4) < 0)
1954 			goto out_resource;
1955 		WRITE32(nfsd4_lease);
1956 	}
1957 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
1958 		if ((buflen -= 4) < 0)
1959 			goto out_resource;
1960 		WRITE32(rdattr_err);
1961 	}
1962 	if (bmval0 & FATTR4_WORD0_ACL) {
1963 		struct nfs4_ace *ace;
1964 
1965 		if (acl == NULL) {
1966 			if ((buflen -= 4) < 0)
1967 				goto out_resource;
1968 
1969 			WRITE32(0);
1970 			goto out_acl;
1971 		}
1972 		if ((buflen -= 4) < 0)
1973 			goto out_resource;
1974 		WRITE32(acl->naces);
1975 
1976 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
1977 			if ((buflen -= 4*3) < 0)
1978 				goto out_resource;
1979 			WRITE32(ace->type);
1980 			WRITE32(ace->flag);
1981 			WRITE32(ace->access_mask & NFS4_ACE_MASK_ALL);
1982 			status = nfsd4_encode_aclname(rqstp, ace->whotype,
1983 				ace->who, ace->flag & NFS4_ACE_IDENTIFIER_GROUP,
1984 				&p, &buflen);
1985 			if (status == nfserr_resource)
1986 				goto out_resource;
1987 			if (status)
1988 				goto out;
1989 		}
1990 	}
1991 out_acl:
1992 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
1993 		if ((buflen -= 4) < 0)
1994 			goto out_resource;
1995 		WRITE32(aclsupport ?
1996 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
1997 	}
1998 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
1999 		if ((buflen -= 4) < 0)
2000 			goto out_resource;
2001 		WRITE32(1);
2002 	}
2003 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2004 		if ((buflen -= 4) < 0)
2005 			goto out_resource;
2006 		WRITE32(1);
2007 	}
2008 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2009 		if ((buflen -= 4) < 0)
2010 			goto out_resource;
2011 		WRITE32(1);
2012 	}
2013 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2014 		if ((buflen -= 4) < 0)
2015 			goto out_resource;
2016 		WRITE32(1);
2017 	}
2018 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2019 		buflen -= (XDR_QUADLEN(fhp->fh_handle.fh_size) << 2) + 4;
2020 		if (buflen < 0)
2021 			goto out_resource;
2022 		WRITE32(fhp->fh_handle.fh_size);
2023 		WRITEMEM(&fhp->fh_handle.fh_base, fhp->fh_handle.fh_size);
2024 	}
2025 	if (bmval0 & FATTR4_WORD0_FILEID) {
2026 		if ((buflen -= 8) < 0)
2027 			goto out_resource;
2028 		WRITE64(stat.ino);
2029 	}
2030 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2031 		if ((buflen -= 8) < 0)
2032 			goto out_resource;
2033 		WRITE64((u64) statfs.f_ffree);
2034 	}
2035 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2036 		if ((buflen -= 8) < 0)
2037 			goto out_resource;
2038 		WRITE64((u64) statfs.f_ffree);
2039 	}
2040 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2041 		if ((buflen -= 8) < 0)
2042 			goto out_resource;
2043 		WRITE64((u64) statfs.f_files);
2044 	}
2045 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2046 		status = nfsd4_encode_fs_locations(rqstp, exp, &p, &buflen);
2047 		if (status == nfserr_resource)
2048 			goto out_resource;
2049 		if (status)
2050 			goto out;
2051 	}
2052 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2053 		if ((buflen -= 4) < 0)
2054 			goto out_resource;
2055 		WRITE32(1);
2056 	}
2057 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2058 		if ((buflen -= 8) < 0)
2059 			goto out_resource;
2060 		WRITE64(~(u64)0);
2061 	}
2062 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2063 		if ((buflen -= 4) < 0)
2064 			goto out_resource;
2065 		WRITE32(255);
2066 	}
2067 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2068 		if ((buflen -= 4) < 0)
2069 			goto out_resource;
2070 		WRITE32(statfs.f_namelen);
2071 	}
2072 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2073 		if ((buflen -= 8) < 0)
2074 			goto out_resource;
2075 		WRITE64((u64) svc_max_payload(rqstp));
2076 	}
2077 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2078 		if ((buflen -= 8) < 0)
2079 			goto out_resource;
2080 		WRITE64((u64) svc_max_payload(rqstp));
2081 	}
2082 	if (bmval1 & FATTR4_WORD1_MODE) {
2083 		if ((buflen -= 4) < 0)
2084 			goto out_resource;
2085 		WRITE32(stat.mode & S_IALLUGO);
2086 	}
2087 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2088 		if ((buflen -= 4) < 0)
2089 			goto out_resource;
2090 		WRITE32(1);
2091 	}
2092 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2093 		if ((buflen -= 4) < 0)
2094 			goto out_resource;
2095 		WRITE32(stat.nlink);
2096 	}
2097 	if (bmval1 & FATTR4_WORD1_OWNER) {
2098 		status = nfsd4_encode_user(rqstp, stat.uid, &p, &buflen);
2099 		if (status == nfserr_resource)
2100 			goto out_resource;
2101 		if (status)
2102 			goto out;
2103 	}
2104 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2105 		status = nfsd4_encode_group(rqstp, stat.gid, &p, &buflen);
2106 		if (status == nfserr_resource)
2107 			goto out_resource;
2108 		if (status)
2109 			goto out;
2110 	}
2111 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2112 		if ((buflen -= 8) < 0)
2113 			goto out_resource;
2114 		WRITE32((u32) MAJOR(stat.rdev));
2115 		WRITE32((u32) MINOR(stat.rdev));
2116 	}
2117 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2118 		if ((buflen -= 8) < 0)
2119 			goto out_resource;
2120 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2121 		WRITE64(dummy64);
2122 	}
2123 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2124 		if ((buflen -= 8) < 0)
2125 			goto out_resource;
2126 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2127 		WRITE64(dummy64);
2128 	}
2129 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2130 		if ((buflen -= 8) < 0)
2131 			goto out_resource;
2132 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2133 		WRITE64(dummy64);
2134 	}
2135 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2136 		if ((buflen -= 8) < 0)
2137 			goto out_resource;
2138 		dummy64 = (u64)stat.blocks << 9;
2139 		WRITE64(dummy64);
2140 	}
2141 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2142 		if ((buflen -= 12) < 0)
2143 			goto out_resource;
2144 		WRITE32(0);
2145 		WRITE32(stat.atime.tv_sec);
2146 		WRITE32(stat.atime.tv_nsec);
2147 	}
2148 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2149 		if ((buflen -= 12) < 0)
2150 			goto out_resource;
2151 		WRITE32(0);
2152 		WRITE32(1);
2153 		WRITE32(0);
2154 	}
2155 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2156 		if ((buflen -= 12) < 0)
2157 			goto out_resource;
2158 		WRITE32(0);
2159 		WRITE32(stat.ctime.tv_sec);
2160 		WRITE32(stat.ctime.tv_nsec);
2161 	}
2162 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2163 		if ((buflen -= 12) < 0)
2164 			goto out_resource;
2165 		WRITE32(0);
2166 		WRITE32(stat.mtime.tv_sec);
2167 		WRITE32(stat.mtime.tv_nsec);
2168 	}
2169 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2170 		if ((buflen -= 8) < 0)
2171                 	goto out_resource;
2172 		/*
2173 		 * Get parent's attributes if not ignoring crossmount
2174 		 * and this is the root of a cross-mounted filesystem.
2175 		 */
2176 		if (ignore_crossmnt == 0 &&
2177 		    dentry == exp->ex_path.mnt->mnt_root) {
2178 			struct path path = exp->ex_path;
2179 			path_get(&path);
2180 			while (follow_up(&path)) {
2181 				if (path.dentry != path.mnt->mnt_root)
2182 					break;
2183 			}
2184 			err = vfs_getattr(path.mnt, path.dentry, &stat);
2185 			path_put(&path);
2186 			if (err)
2187 				goto out_nfserr;
2188 		}
2189 		WRITE64(stat.ino);
2190 	}
2191 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2192 		WRITE32(3);
2193 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD0);
2194 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD1);
2195 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD2);
2196 	}
2197 
2198 	*attrlenp = htonl((char *)p - (char *)attrlenp - 4);
2199 	*countp = p - buffer;
2200 	status = nfs_ok;
2201 
2202 out:
2203 	kfree(acl);
2204 	if (fhp == &tempfh)
2205 		fh_put(&tempfh);
2206 	return status;
2207 out_nfserr:
2208 	status = nfserrno(err);
2209 	goto out;
2210 out_resource:
2211 	*countp = 0;
2212 	status = nfserr_resource;
2213 	goto out;
2214 out_serverfault:
2215 	status = nfserr_serverfault;
2216 	goto out;
2217 }
2218 
2219 static inline int attributes_need_mount(u32 *bmval)
2220 {
2221 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2222 		return 1;
2223 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2224 		return 1;
2225 	return 0;
2226 }
2227 
2228 static __be32
2229 nfsd4_encode_dirent_fattr(struct nfsd4_readdir *cd,
2230 		const char *name, int namlen, __be32 *p, int *buflen)
2231 {
2232 	struct svc_export *exp = cd->rd_fhp->fh_export;
2233 	struct dentry *dentry;
2234 	__be32 nfserr;
2235 	int ignore_crossmnt = 0;
2236 
2237 	dentry = lookup_one_len(name, cd->rd_fhp->fh_dentry, namlen);
2238 	if (IS_ERR(dentry))
2239 		return nfserrno(PTR_ERR(dentry));
2240 	if (!dentry->d_inode) {
2241 		/*
2242 		 * nfsd_buffered_readdir drops the i_mutex between
2243 		 * readdir and calling this callback, leaving a window
2244 		 * where this directory entry could have gone away.
2245 		 */
2246 		dput(dentry);
2247 		return nfserr_noent;
2248 	}
2249 
2250 	exp_get(exp);
2251 	/*
2252 	 * In the case of a mountpoint, the client may be asking for
2253 	 * attributes that are only properties of the underlying filesystem
2254 	 * as opposed to the cross-mounted file system. In such a case,
2255 	 * we will not follow the cross mount and will fill the attribtutes
2256 	 * directly from the mountpoint dentry.
2257 	 */
2258 	if (nfsd_mountpoint(dentry, exp)) {
2259 		int err;
2260 
2261 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
2262 				&& !attributes_need_mount(cd->rd_bmval)) {
2263 			ignore_crossmnt = 1;
2264 			goto out_encode;
2265 		}
2266 		/*
2267 		 * Why the heck aren't we just using nfsd_lookup??
2268 		 * Different "."/".." handling?  Something else?
2269 		 * At least, add a comment here to explain....
2270 		 */
2271 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
2272 		if (err) {
2273 			nfserr = nfserrno(err);
2274 			goto out_put;
2275 		}
2276 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
2277 		if (nfserr)
2278 			goto out_put;
2279 
2280 	}
2281 out_encode:
2282 	nfserr = nfsd4_encode_fattr(NULL, exp, dentry, p, buflen, cd->rd_bmval,
2283 					cd->rd_rqstp, ignore_crossmnt);
2284 out_put:
2285 	dput(dentry);
2286 	exp_put(exp);
2287 	return nfserr;
2288 }
2289 
2290 static __be32 *
2291 nfsd4_encode_rdattr_error(__be32 *p, int buflen, __be32 nfserr)
2292 {
2293 	__be32 *attrlenp;
2294 
2295 	if (buflen < 6)
2296 		return NULL;
2297 	*p++ = htonl(2);
2298 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
2299 	*p++ = htonl(0);			 /* bmval1 */
2300 
2301 	attrlenp = p++;
2302 	*p++ = nfserr;       /* no htonl */
2303 	*attrlenp = htonl((char *)p - (char *)attrlenp - 4);
2304 	return p;
2305 }
2306 
2307 static int
2308 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
2309 		    loff_t offset, u64 ino, unsigned int d_type)
2310 {
2311 	struct readdir_cd *ccd = ccdv;
2312 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
2313 	int buflen;
2314 	__be32 *p = cd->buffer;
2315 	__be32 *cookiep;
2316 	__be32 nfserr = nfserr_toosmall;
2317 
2318 	/* In nfsv4, "." and ".." never make it onto the wire.. */
2319 	if (name && isdotent(name, namlen)) {
2320 		cd->common.err = nfs_ok;
2321 		return 0;
2322 	}
2323 
2324 	if (cd->offset)
2325 		xdr_encode_hyper(cd->offset, (u64) offset);
2326 
2327 	buflen = cd->buflen - 4 - XDR_QUADLEN(namlen);
2328 	if (buflen < 0)
2329 		goto fail;
2330 
2331 	*p++ = xdr_one;                             /* mark entry present */
2332 	cookiep = p;
2333 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
2334 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
2335 
2336 	nfserr = nfsd4_encode_dirent_fattr(cd, name, namlen, p, &buflen);
2337 	switch (nfserr) {
2338 	case nfs_ok:
2339 		p += buflen;
2340 		break;
2341 	case nfserr_resource:
2342 		nfserr = nfserr_toosmall;
2343 		goto fail;
2344 	case nfserr_noent:
2345 		goto skip_entry;
2346 	default:
2347 		/*
2348 		 * If the client requested the RDATTR_ERROR attribute,
2349 		 * we stuff the error code into this attribute
2350 		 * and continue.  If this attribute was not requested,
2351 		 * then in accordance with the spec, we fail the
2352 		 * entire READDIR operation(!)
2353 		 */
2354 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
2355 			goto fail;
2356 		p = nfsd4_encode_rdattr_error(p, buflen, nfserr);
2357 		if (p == NULL) {
2358 			nfserr = nfserr_toosmall;
2359 			goto fail;
2360 		}
2361 	}
2362 	cd->buflen -= (p - cd->buffer);
2363 	cd->buffer = p;
2364 	cd->offset = cookiep;
2365 skip_entry:
2366 	cd->common.err = nfs_ok;
2367 	return 0;
2368 fail:
2369 	cd->common.err = nfserr;
2370 	return -EINVAL;
2371 }
2372 
2373 static void
2374 nfsd4_encode_stateid(struct nfsd4_compoundres *resp, stateid_t *sid)
2375 {
2376 	__be32 *p;
2377 
2378 	RESERVE_SPACE(sizeof(stateid_t));
2379 	WRITE32(sid->si_generation);
2380 	WRITEMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
2381 	ADJUST_ARGS();
2382 }
2383 
2384 static __be32
2385 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
2386 {
2387 	__be32 *p;
2388 
2389 	if (!nfserr) {
2390 		RESERVE_SPACE(8);
2391 		WRITE32(access->ac_supported);
2392 		WRITE32(access->ac_resp_access);
2393 		ADJUST_ARGS();
2394 	}
2395 	return nfserr;
2396 }
2397 
2398 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
2399 {
2400 	__be32 *p;
2401 
2402 	if (!nfserr) {
2403 		RESERVE_SPACE(NFS4_MAX_SESSIONID_LEN + 8);
2404 		WRITEMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
2405 		WRITE32(bcts->dir);
2406 		/* XXX: ? */
2407 		WRITE32(0);
2408 		ADJUST_ARGS();
2409 	}
2410 	return nfserr;
2411 }
2412 
2413 static __be32
2414 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
2415 {
2416 	ENCODE_SEQID_OP_HEAD;
2417 
2418 	if (!nfserr)
2419 		nfsd4_encode_stateid(resp, &close->cl_stateid);
2420 
2421 	ENCODE_SEQID_OP_TAIL(close->cl_stateowner);
2422 	return nfserr;
2423 }
2424 
2425 
2426 static __be32
2427 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
2428 {
2429 	__be32 *p;
2430 
2431 	if (!nfserr) {
2432 		RESERVE_SPACE(8);
2433 		WRITEMEM(commit->co_verf.data, 8);
2434 		ADJUST_ARGS();
2435 	}
2436 	return nfserr;
2437 }
2438 
2439 static __be32
2440 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
2441 {
2442 	__be32 *p;
2443 
2444 	if (!nfserr) {
2445 		RESERVE_SPACE(32);
2446 		write_cinfo(&p, &create->cr_cinfo);
2447 		WRITE32(2);
2448 		WRITE32(create->cr_bmval[0]);
2449 		WRITE32(create->cr_bmval[1]);
2450 		ADJUST_ARGS();
2451 	}
2452 	return nfserr;
2453 }
2454 
2455 static __be32
2456 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
2457 {
2458 	struct svc_fh *fhp = getattr->ga_fhp;
2459 	int buflen;
2460 
2461 	if (nfserr)
2462 		return nfserr;
2463 
2464 	buflen = resp->end - resp->p - (COMPOUND_ERR_SLACK_SPACE >> 2);
2465 	nfserr = nfsd4_encode_fattr(fhp, fhp->fh_export, fhp->fh_dentry,
2466 				    resp->p, &buflen, getattr->ga_bmval,
2467 				    resp->rqstp, 0);
2468 	if (!nfserr)
2469 		resp->p += buflen;
2470 	return nfserr;
2471 }
2472 
2473 static __be32
2474 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
2475 {
2476 	struct svc_fh *fhp = *fhpp;
2477 	unsigned int len;
2478 	__be32 *p;
2479 
2480 	if (!nfserr) {
2481 		len = fhp->fh_handle.fh_size;
2482 		RESERVE_SPACE(len + 4);
2483 		WRITE32(len);
2484 		WRITEMEM(&fhp->fh_handle.fh_base, len);
2485 		ADJUST_ARGS();
2486 	}
2487 	return nfserr;
2488 }
2489 
2490 /*
2491 * Including all fields other than the name, a LOCK4denied structure requires
2492 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
2493 */
2494 static void
2495 nfsd4_encode_lock_denied(struct nfsd4_compoundres *resp, struct nfsd4_lock_denied *ld)
2496 {
2497 	__be32 *p;
2498 
2499 	RESERVE_SPACE(32 + XDR_LEN(ld->ld_sop ? ld->ld_sop->so_owner.len : 0));
2500 	WRITE64(ld->ld_start);
2501 	WRITE64(ld->ld_length);
2502 	WRITE32(ld->ld_type);
2503 	if (ld->ld_sop) {
2504 		WRITEMEM(&ld->ld_clientid, 8);
2505 		WRITE32(ld->ld_sop->so_owner.len);
2506 		WRITEMEM(ld->ld_sop->so_owner.data, ld->ld_sop->so_owner.len);
2507 		kref_put(&ld->ld_sop->so_ref, nfs4_free_stateowner);
2508 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
2509 		WRITE64((u64)0); /* clientid */
2510 		WRITE32(0); /* length of owner name */
2511 	}
2512 	ADJUST_ARGS();
2513 }
2514 
2515 static __be32
2516 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
2517 {
2518 	ENCODE_SEQID_OP_HEAD;
2519 
2520 	if (!nfserr)
2521 		nfsd4_encode_stateid(resp, &lock->lk_resp_stateid);
2522 	else if (nfserr == nfserr_denied)
2523 		nfsd4_encode_lock_denied(resp, &lock->lk_denied);
2524 
2525 	ENCODE_SEQID_OP_TAIL(lock->lk_replay_owner);
2526 	return nfserr;
2527 }
2528 
2529 static __be32
2530 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
2531 {
2532 	if (nfserr == nfserr_denied)
2533 		nfsd4_encode_lock_denied(resp, &lockt->lt_denied);
2534 	return nfserr;
2535 }
2536 
2537 static __be32
2538 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
2539 {
2540 	ENCODE_SEQID_OP_HEAD;
2541 
2542 	if (!nfserr)
2543 		nfsd4_encode_stateid(resp, &locku->lu_stateid);
2544 
2545 	ENCODE_SEQID_OP_TAIL(locku->lu_stateowner);
2546 	return nfserr;
2547 }
2548 
2549 
2550 static __be32
2551 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
2552 {
2553 	__be32 *p;
2554 
2555 	if (!nfserr) {
2556 		RESERVE_SPACE(20);
2557 		write_cinfo(&p, &link->li_cinfo);
2558 		ADJUST_ARGS();
2559 	}
2560 	return nfserr;
2561 }
2562 
2563 
2564 static __be32
2565 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
2566 {
2567 	__be32 *p;
2568 	ENCODE_SEQID_OP_HEAD;
2569 
2570 	if (nfserr)
2571 		goto out;
2572 
2573 	nfsd4_encode_stateid(resp, &open->op_stateid);
2574 	RESERVE_SPACE(40);
2575 	write_cinfo(&p, &open->op_cinfo);
2576 	WRITE32(open->op_rflags);
2577 	WRITE32(2);
2578 	WRITE32(open->op_bmval[0]);
2579 	WRITE32(open->op_bmval[1]);
2580 	WRITE32(open->op_delegate_type);
2581 	ADJUST_ARGS();
2582 
2583 	switch (open->op_delegate_type) {
2584 	case NFS4_OPEN_DELEGATE_NONE:
2585 		break;
2586 	case NFS4_OPEN_DELEGATE_READ:
2587 		nfsd4_encode_stateid(resp, &open->op_delegate_stateid);
2588 		RESERVE_SPACE(20);
2589 		WRITE32(open->op_recall);
2590 
2591 		/*
2592 		 * TODO: ACE's in delegations
2593 		 */
2594 		WRITE32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
2595 		WRITE32(0);
2596 		WRITE32(0);
2597 		WRITE32(0);   /* XXX: is NULL principal ok? */
2598 		ADJUST_ARGS();
2599 		break;
2600 	case NFS4_OPEN_DELEGATE_WRITE:
2601 		nfsd4_encode_stateid(resp, &open->op_delegate_stateid);
2602 		RESERVE_SPACE(32);
2603 		WRITE32(0);
2604 
2605 		/*
2606 		 * TODO: space_limit's in delegations
2607 		 */
2608 		WRITE32(NFS4_LIMIT_SIZE);
2609 		WRITE32(~(u32)0);
2610 		WRITE32(~(u32)0);
2611 
2612 		/*
2613 		 * TODO: ACE's in delegations
2614 		 */
2615 		WRITE32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
2616 		WRITE32(0);
2617 		WRITE32(0);
2618 		WRITE32(0);   /* XXX: is NULL principal ok? */
2619 		ADJUST_ARGS();
2620 		break;
2621 	default:
2622 		BUG();
2623 	}
2624 	/* XXX save filehandle here */
2625 out:
2626 	ENCODE_SEQID_OP_TAIL(open->op_stateowner);
2627 	return nfserr;
2628 }
2629 
2630 static __be32
2631 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
2632 {
2633 	ENCODE_SEQID_OP_HEAD;
2634 
2635 	if (!nfserr)
2636 		nfsd4_encode_stateid(resp, &oc->oc_resp_stateid);
2637 
2638 	ENCODE_SEQID_OP_TAIL(oc->oc_stateowner);
2639 	return nfserr;
2640 }
2641 
2642 static __be32
2643 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
2644 {
2645 	ENCODE_SEQID_OP_HEAD;
2646 
2647 	if (!nfserr)
2648 		nfsd4_encode_stateid(resp, &od->od_stateid);
2649 
2650 	ENCODE_SEQID_OP_TAIL(od->od_stateowner);
2651 	return nfserr;
2652 }
2653 
2654 static __be32
2655 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
2656 		  struct nfsd4_read *read)
2657 {
2658 	u32 eof;
2659 	int v, pn;
2660 	unsigned long maxcount;
2661 	long len;
2662 	__be32 *p;
2663 
2664 	if (nfserr)
2665 		return nfserr;
2666 	if (resp->xbuf->page_len)
2667 		return nfserr_resource;
2668 
2669 	RESERVE_SPACE(8); /* eof flag and byte count */
2670 
2671 	maxcount = svc_max_payload(resp->rqstp);
2672 	if (maxcount > read->rd_length)
2673 		maxcount = read->rd_length;
2674 
2675 	len = maxcount;
2676 	v = 0;
2677 	while (len > 0) {
2678 		pn = resp->rqstp->rq_resused++;
2679 		resp->rqstp->rq_vec[v].iov_base =
2680 			page_address(resp->rqstp->rq_respages[pn]);
2681 		resp->rqstp->rq_vec[v].iov_len =
2682 			len < PAGE_SIZE ? len : PAGE_SIZE;
2683 		v++;
2684 		len -= PAGE_SIZE;
2685 	}
2686 	read->rd_vlen = v;
2687 
2688 	nfserr = nfsd_read_file(read->rd_rqstp, read->rd_fhp, read->rd_filp,
2689 			read->rd_offset, resp->rqstp->rq_vec, read->rd_vlen,
2690 			&maxcount);
2691 
2692 	if (nfserr == nfserr_symlink)
2693 		nfserr = nfserr_inval;
2694 	if (nfserr)
2695 		return nfserr;
2696 	eof = (read->rd_offset + maxcount >=
2697 	       read->rd_fhp->fh_dentry->d_inode->i_size);
2698 
2699 	WRITE32(eof);
2700 	WRITE32(maxcount);
2701 	ADJUST_ARGS();
2702 	resp->xbuf->head[0].iov_len = (char*)p
2703 					- (char*)resp->xbuf->head[0].iov_base;
2704 	resp->xbuf->page_len = maxcount;
2705 
2706 	/* Use rest of head for padding and remaining ops: */
2707 	resp->xbuf->tail[0].iov_base = p;
2708 	resp->xbuf->tail[0].iov_len = 0;
2709 	if (maxcount&3) {
2710 		RESERVE_SPACE(4);
2711 		WRITE32(0);
2712 		resp->xbuf->tail[0].iov_base += maxcount&3;
2713 		resp->xbuf->tail[0].iov_len = 4 - (maxcount&3);
2714 		ADJUST_ARGS();
2715 	}
2716 	return 0;
2717 }
2718 
2719 static __be32
2720 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
2721 {
2722 	int maxcount;
2723 	char *page;
2724 	__be32 *p;
2725 
2726 	if (nfserr)
2727 		return nfserr;
2728 	if (resp->xbuf->page_len)
2729 		return nfserr_resource;
2730 
2731 	page = page_address(resp->rqstp->rq_respages[resp->rqstp->rq_resused++]);
2732 
2733 	maxcount = PAGE_SIZE;
2734 	RESERVE_SPACE(4);
2735 
2736 	/*
2737 	 * XXX: By default, the ->readlink() VFS op will truncate symlinks
2738 	 * if they would overflow the buffer.  Is this kosher in NFSv4?  If
2739 	 * not, one easy fix is: if ->readlink() precisely fills the buffer,
2740 	 * assume that truncation occurred, and return NFS4ERR_RESOURCE.
2741 	 */
2742 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp, page, &maxcount);
2743 	if (nfserr == nfserr_isdir)
2744 		return nfserr_inval;
2745 	if (nfserr)
2746 		return nfserr;
2747 
2748 	WRITE32(maxcount);
2749 	ADJUST_ARGS();
2750 	resp->xbuf->head[0].iov_len = (char*)p
2751 				- (char*)resp->xbuf->head[0].iov_base;
2752 	resp->xbuf->page_len = maxcount;
2753 
2754 	/* Use rest of head for padding and remaining ops: */
2755 	resp->xbuf->tail[0].iov_base = p;
2756 	resp->xbuf->tail[0].iov_len = 0;
2757 	if (maxcount&3) {
2758 		RESERVE_SPACE(4);
2759 		WRITE32(0);
2760 		resp->xbuf->tail[0].iov_base += maxcount&3;
2761 		resp->xbuf->tail[0].iov_len = 4 - (maxcount&3);
2762 		ADJUST_ARGS();
2763 	}
2764 	return 0;
2765 }
2766 
2767 static __be32
2768 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
2769 {
2770 	int maxcount;
2771 	loff_t offset;
2772 	__be32 *page, *savep, *tailbase;
2773 	__be32 *p;
2774 
2775 	if (nfserr)
2776 		return nfserr;
2777 	if (resp->xbuf->page_len)
2778 		return nfserr_resource;
2779 
2780 	RESERVE_SPACE(8);  /* verifier */
2781 	savep = p;
2782 
2783 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
2784 	WRITE32(0);
2785 	WRITE32(0);
2786 	ADJUST_ARGS();
2787 	resp->xbuf->head[0].iov_len = ((char*)resp->p) - (char*)resp->xbuf->head[0].iov_base;
2788 	tailbase = p;
2789 
2790 	maxcount = PAGE_SIZE;
2791 	if (maxcount > readdir->rd_maxcount)
2792 		maxcount = readdir->rd_maxcount;
2793 
2794 	/*
2795 	 * Convert from bytes to words, account for the two words already
2796 	 * written, make sure to leave two words at the end for the next
2797 	 * pointer and eof field.
2798 	 */
2799 	maxcount = (maxcount >> 2) - 4;
2800 	if (maxcount < 0) {
2801 		nfserr =  nfserr_toosmall;
2802 		goto err_no_verf;
2803 	}
2804 
2805 	page = page_address(resp->rqstp->rq_respages[resp->rqstp->rq_resused++]);
2806 	readdir->common.err = 0;
2807 	readdir->buflen = maxcount;
2808 	readdir->buffer = page;
2809 	readdir->offset = NULL;
2810 
2811 	offset = readdir->rd_cookie;
2812 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
2813 			      &offset,
2814 			      &readdir->common, nfsd4_encode_dirent);
2815 	if (nfserr == nfs_ok &&
2816 	    readdir->common.err == nfserr_toosmall &&
2817 	    readdir->buffer == page)
2818 		nfserr = nfserr_toosmall;
2819 	if (nfserr == nfserr_symlink)
2820 		nfserr = nfserr_notdir;
2821 	if (nfserr)
2822 		goto err_no_verf;
2823 
2824 	if (readdir->offset)
2825 		xdr_encode_hyper(readdir->offset, offset);
2826 
2827 	p = readdir->buffer;
2828 	*p++ = 0;	/* no more entries */
2829 	*p++ = htonl(readdir->common.err == nfserr_eof);
2830 	resp->xbuf->page_len = ((char*)p) - (char*)page_address(
2831 		resp->rqstp->rq_respages[resp->rqstp->rq_resused-1]);
2832 
2833 	/* Use rest of head for padding and remaining ops: */
2834 	resp->xbuf->tail[0].iov_base = tailbase;
2835 	resp->xbuf->tail[0].iov_len = 0;
2836 	resp->p = resp->xbuf->tail[0].iov_base;
2837 	resp->end = resp->p + (PAGE_SIZE - resp->xbuf->head[0].iov_len)/4;
2838 
2839 	return 0;
2840 err_no_verf:
2841 	p = savep;
2842 	ADJUST_ARGS();
2843 	return nfserr;
2844 }
2845 
2846 static __be32
2847 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
2848 {
2849 	__be32 *p;
2850 
2851 	if (!nfserr) {
2852 		RESERVE_SPACE(20);
2853 		write_cinfo(&p, &remove->rm_cinfo);
2854 		ADJUST_ARGS();
2855 	}
2856 	return nfserr;
2857 }
2858 
2859 static __be32
2860 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
2861 {
2862 	__be32 *p;
2863 
2864 	if (!nfserr) {
2865 		RESERVE_SPACE(40);
2866 		write_cinfo(&p, &rename->rn_sinfo);
2867 		write_cinfo(&p, &rename->rn_tinfo);
2868 		ADJUST_ARGS();
2869 	}
2870 	return nfserr;
2871 }
2872 
2873 static __be32
2874 nfsd4_do_encode_secinfo(struct nfsd4_compoundres *resp,
2875 			 __be32 nfserr,struct svc_export *exp)
2876 {
2877 	int i = 0;
2878 	u32 nflavs;
2879 	struct exp_flavor_info *flavs;
2880 	struct exp_flavor_info def_flavs[2];
2881 	__be32 *p;
2882 
2883 	if (nfserr)
2884 		goto out;
2885 	if (exp->ex_nflavors) {
2886 		flavs = exp->ex_flavors;
2887 		nflavs = exp->ex_nflavors;
2888 	} else { /* Handling of some defaults in absence of real secinfo: */
2889 		flavs = def_flavs;
2890 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
2891 			nflavs = 2;
2892 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
2893 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
2894 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
2895 			nflavs = 1;
2896 			flavs[0].pseudoflavor
2897 					= svcauth_gss_flavor(exp->ex_client);
2898 		} else {
2899 			nflavs = 1;
2900 			flavs[0].pseudoflavor
2901 					= exp->ex_client->flavour->flavour;
2902 		}
2903 	}
2904 
2905 	RESERVE_SPACE(4);
2906 	WRITE32(nflavs);
2907 	ADJUST_ARGS();
2908 	for (i = 0; i < nflavs; i++) {
2909 		u32 flav = flavs[i].pseudoflavor;
2910 		struct gss_api_mech *gm = gss_mech_get_by_pseudoflavor(flav);
2911 
2912 		if (gm) {
2913 			RESERVE_SPACE(4);
2914 			WRITE32(RPC_AUTH_GSS);
2915 			ADJUST_ARGS();
2916 			RESERVE_SPACE(4 + gm->gm_oid.len);
2917 			WRITE32(gm->gm_oid.len);
2918 			WRITEMEM(gm->gm_oid.data, gm->gm_oid.len);
2919 			ADJUST_ARGS();
2920 			RESERVE_SPACE(4);
2921 			WRITE32(0); /* qop */
2922 			ADJUST_ARGS();
2923 			RESERVE_SPACE(4);
2924 			WRITE32(gss_pseudoflavor_to_service(gm, flav));
2925 			ADJUST_ARGS();
2926 			gss_mech_put(gm);
2927 		} else {
2928 			RESERVE_SPACE(4);
2929 			WRITE32(flav);
2930 			ADJUST_ARGS();
2931 		}
2932 	}
2933 out:
2934 	if (exp)
2935 		exp_put(exp);
2936 	return nfserr;
2937 }
2938 
2939 static __be32
2940 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
2941 		     struct nfsd4_secinfo *secinfo)
2942 {
2943 	return nfsd4_do_encode_secinfo(resp, nfserr, secinfo->si_exp);
2944 }
2945 
2946 static __be32
2947 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
2948 		     struct nfsd4_secinfo_no_name *secinfo)
2949 {
2950 	return nfsd4_do_encode_secinfo(resp, nfserr, secinfo->sin_exp);
2951 }
2952 
2953 /*
2954  * The SETATTR encode routine is special -- it always encodes a bitmap,
2955  * regardless of the error status.
2956  */
2957 static __be32
2958 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
2959 {
2960 	__be32 *p;
2961 
2962 	RESERVE_SPACE(12);
2963 	if (nfserr) {
2964 		WRITE32(2);
2965 		WRITE32(0);
2966 		WRITE32(0);
2967 	}
2968 	else {
2969 		WRITE32(2);
2970 		WRITE32(setattr->sa_bmval[0]);
2971 		WRITE32(setattr->sa_bmval[1]);
2972 	}
2973 	ADJUST_ARGS();
2974 	return nfserr;
2975 }
2976 
2977 static __be32
2978 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
2979 {
2980 	__be32 *p;
2981 
2982 	if (!nfserr) {
2983 		RESERVE_SPACE(8 + sizeof(nfs4_verifier));
2984 		WRITEMEM(&scd->se_clientid, 8);
2985 		WRITEMEM(&scd->se_confirm, sizeof(nfs4_verifier));
2986 		ADJUST_ARGS();
2987 	}
2988 	else if (nfserr == nfserr_clid_inuse) {
2989 		RESERVE_SPACE(8);
2990 		WRITE32(0);
2991 		WRITE32(0);
2992 		ADJUST_ARGS();
2993 	}
2994 	return nfserr;
2995 }
2996 
2997 static __be32
2998 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
2999 {
3000 	__be32 *p;
3001 
3002 	if (!nfserr) {
3003 		RESERVE_SPACE(16);
3004 		WRITE32(write->wr_bytes_written);
3005 		WRITE32(write->wr_how_written);
3006 		WRITEMEM(write->wr_verifier.data, 8);
3007 		ADJUST_ARGS();
3008 	}
3009 	return nfserr;
3010 }
3011 
3012 static __be32
3013 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, int nfserr,
3014 			 struct nfsd4_exchange_id *exid)
3015 {
3016 	__be32 *p;
3017 	char *major_id;
3018 	char *server_scope;
3019 	int major_id_sz;
3020 	int server_scope_sz;
3021 	uint64_t minor_id = 0;
3022 
3023 	if (nfserr)
3024 		return nfserr;
3025 
3026 	major_id = utsname()->nodename;
3027 	major_id_sz = strlen(major_id);
3028 	server_scope = utsname()->nodename;
3029 	server_scope_sz = strlen(server_scope);
3030 
3031 	RESERVE_SPACE(
3032 		8 /* eir_clientid */ +
3033 		4 /* eir_sequenceid */ +
3034 		4 /* eir_flags */ +
3035 		4 /* spr_how (SP4_NONE) */ +
3036 		8 /* so_minor_id */ +
3037 		4 /* so_major_id.len */ +
3038 		(XDR_QUADLEN(major_id_sz) * 4) +
3039 		4 /* eir_server_scope.len */ +
3040 		(XDR_QUADLEN(server_scope_sz) * 4) +
3041 		4 /* eir_server_impl_id.count (0) */);
3042 
3043 	WRITEMEM(&exid->clientid, 8);
3044 	WRITE32(exid->seqid);
3045 	WRITE32(exid->flags);
3046 
3047 	/* state_protect4_r. Currently only support SP4_NONE */
3048 	BUG_ON(exid->spa_how != SP4_NONE);
3049 	WRITE32(exid->spa_how);
3050 
3051 	/* The server_owner struct */
3052 	WRITE64(minor_id);      /* Minor id */
3053 	/* major id */
3054 	WRITE32(major_id_sz);
3055 	WRITEMEM(major_id, major_id_sz);
3056 
3057 	/* Server scope */
3058 	WRITE32(server_scope_sz);
3059 	WRITEMEM(server_scope, server_scope_sz);
3060 
3061 	/* Implementation id */
3062 	WRITE32(0);	/* zero length nfs_impl_id4 array */
3063 	ADJUST_ARGS();
3064 	return 0;
3065 }
3066 
3067 static __be32
3068 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, int nfserr,
3069 			    struct nfsd4_create_session *sess)
3070 {
3071 	__be32 *p;
3072 
3073 	if (nfserr)
3074 		return nfserr;
3075 
3076 	RESERVE_SPACE(24);
3077 	WRITEMEM(sess->sessionid.data, NFS4_MAX_SESSIONID_LEN);
3078 	WRITE32(sess->seqid);
3079 	WRITE32(sess->flags);
3080 	ADJUST_ARGS();
3081 
3082 	RESERVE_SPACE(28);
3083 	WRITE32(0); /* headerpadsz */
3084 	WRITE32(sess->fore_channel.maxreq_sz);
3085 	WRITE32(sess->fore_channel.maxresp_sz);
3086 	WRITE32(sess->fore_channel.maxresp_cached);
3087 	WRITE32(sess->fore_channel.maxops);
3088 	WRITE32(sess->fore_channel.maxreqs);
3089 	WRITE32(sess->fore_channel.nr_rdma_attrs);
3090 	ADJUST_ARGS();
3091 
3092 	if (sess->fore_channel.nr_rdma_attrs) {
3093 		RESERVE_SPACE(4);
3094 		WRITE32(sess->fore_channel.rdma_attrs);
3095 		ADJUST_ARGS();
3096 	}
3097 
3098 	RESERVE_SPACE(28);
3099 	WRITE32(0); /* headerpadsz */
3100 	WRITE32(sess->back_channel.maxreq_sz);
3101 	WRITE32(sess->back_channel.maxresp_sz);
3102 	WRITE32(sess->back_channel.maxresp_cached);
3103 	WRITE32(sess->back_channel.maxops);
3104 	WRITE32(sess->back_channel.maxreqs);
3105 	WRITE32(sess->back_channel.nr_rdma_attrs);
3106 	ADJUST_ARGS();
3107 
3108 	if (sess->back_channel.nr_rdma_attrs) {
3109 		RESERVE_SPACE(4);
3110 		WRITE32(sess->back_channel.rdma_attrs);
3111 		ADJUST_ARGS();
3112 	}
3113 	return 0;
3114 }
3115 
3116 static __be32
3117 nfsd4_encode_destroy_session(struct nfsd4_compoundres *resp, int nfserr,
3118 			     struct nfsd4_destroy_session *destroy_session)
3119 {
3120 	return nfserr;
3121 }
3122 
3123 __be32
3124 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, int nfserr,
3125 		      struct nfsd4_sequence *seq)
3126 {
3127 	__be32 *p;
3128 
3129 	if (nfserr)
3130 		return nfserr;
3131 
3132 	RESERVE_SPACE(NFS4_MAX_SESSIONID_LEN + 20);
3133 	WRITEMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
3134 	WRITE32(seq->seqid);
3135 	WRITE32(seq->slotid);
3136 	WRITE32(seq->maxslots);
3137 	/* For now: target_maxslots = maxslots */
3138 	WRITE32(seq->maxslots);
3139 	WRITE32(seq->status_flags);
3140 
3141 	ADJUST_ARGS();
3142 	resp->cstate.datap = p; /* DRC cache data pointer */
3143 	return 0;
3144 }
3145 
3146 static __be32
3147 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
3148 {
3149 	return nfserr;
3150 }
3151 
3152 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
3153 
3154 /*
3155  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
3156  * since we don't need to filter out obsolete ops as this is
3157  * done in the decoding phase.
3158  */
3159 static nfsd4_enc nfsd4_enc_ops[] = {
3160 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
3161 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
3162 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
3163 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
3164 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
3165 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
3166 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
3167 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
3168 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
3169 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
3170 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
3171 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
3172 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
3173 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
3174 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
3175 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
3176 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
3177 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
3178 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
3179 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
3180 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
3181 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
3182 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
3183 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
3184 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
3185 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
3186 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
3187 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
3188 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
3189 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
3190 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
3191 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
3192 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
3193 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
3194 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
3195 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
3196 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
3197 
3198 	/* NFSv4.1 operations */
3199 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
3200 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
3201 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
3202 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
3203 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_destroy_session,
3204 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
3205 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
3206 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
3207 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
3208 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
3209 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
3210 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
3211 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
3212 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
3213 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
3214 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
3215 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
3216 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
3217 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
3218 };
3219 
3220 /*
3221  * Calculate the total amount of memory that the compound response has taken
3222  * after encoding the current operation.
3223  *
3224  * pad: add on 8 bytes for the next operation's op_code and status so that
3225  * there is room to cache a failure on the next operation.
3226  *
3227  * Compare this length to the session se_fmaxresp_cached.
3228  *
3229  * Our se_fmaxresp_cached will always be a multiple of PAGE_SIZE, and so
3230  * will be at least a page and will therefore hold the xdr_buf head.
3231  */
3232 static int nfsd4_check_drc_limit(struct nfsd4_compoundres *resp)
3233 {
3234 	int status = 0;
3235 	struct xdr_buf *xb = &resp->rqstp->rq_res;
3236 	struct nfsd4_compoundargs *args = resp->rqstp->rq_argp;
3237 	struct nfsd4_session *session = NULL;
3238 	struct nfsd4_slot *slot = resp->cstate.slot;
3239 	u32 length, tlen = 0, pad = 8;
3240 
3241 	if (!nfsd4_has_session(&resp->cstate))
3242 		return status;
3243 
3244 	session = resp->cstate.session;
3245 	if (session == NULL || slot->sl_cachethis == 0)
3246 		return status;
3247 
3248 	if (resp->opcnt >= args->opcnt)
3249 		pad = 0; /* this is the last operation */
3250 
3251 	if (xb->page_len == 0) {
3252 		length = (char *)resp->p - (char *)xb->head[0].iov_base + pad;
3253 	} else {
3254 		if (xb->tail[0].iov_base && xb->tail[0].iov_len > 0)
3255 			tlen = (char *)resp->p - (char *)xb->tail[0].iov_base;
3256 
3257 		length = xb->head[0].iov_len + xb->page_len + tlen + pad;
3258 	}
3259 	dprintk("%s length %u, xb->page_len %u tlen %u pad %u\n", __func__,
3260 		length, xb->page_len, tlen, pad);
3261 
3262 	if (length <= session->se_fchannel.maxresp_cached)
3263 		return status;
3264 	else
3265 		return nfserr_rep_too_big_to_cache;
3266 }
3267 
3268 void
3269 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
3270 {
3271 	__be32 *statp;
3272 	__be32 *p;
3273 
3274 	RESERVE_SPACE(8);
3275 	WRITE32(op->opnum);
3276 	statp = p++;	/* to be backfilled at the end */
3277 	ADJUST_ARGS();
3278 
3279 	if (op->opnum == OP_ILLEGAL)
3280 		goto status;
3281 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
3282 	       !nfsd4_enc_ops[op->opnum]);
3283 	op->status = nfsd4_enc_ops[op->opnum](resp, op->status, &op->u);
3284 	/* nfsd4_check_drc_limit guarantees enough room for error status */
3285 	if (!op->status && nfsd4_check_drc_limit(resp))
3286 		op->status = nfserr_rep_too_big_to_cache;
3287 status:
3288 	/*
3289 	 * Note: We write the status directly, instead of using WRITE32(),
3290 	 * since it is already in network byte order.
3291 	 */
3292 	*statp = op->status;
3293 }
3294 
3295 /*
3296  * Encode the reply stored in the stateowner reply cache
3297  *
3298  * XDR note: do not encode rp->rp_buflen: the buffer contains the
3299  * previously sent already encoded operation.
3300  *
3301  * called with nfs4_lock_state() held
3302  */
3303 void
3304 nfsd4_encode_replay(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
3305 {
3306 	__be32 *p;
3307 	struct nfs4_replay *rp = op->replay;
3308 
3309 	BUG_ON(!rp);
3310 
3311 	RESERVE_SPACE(8);
3312 	WRITE32(op->opnum);
3313 	*p++ = rp->rp_status;  /* already xdr'ed */
3314 	ADJUST_ARGS();
3315 
3316 	RESERVE_SPACE(rp->rp_buflen);
3317 	WRITEMEM(rp->rp_buf, rp->rp_buflen);
3318 	ADJUST_ARGS();
3319 }
3320 
3321 int
3322 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
3323 {
3324         return xdr_ressize_check(rqstp, p);
3325 }
3326 
3327 void nfsd4_release_compoundargs(struct nfsd4_compoundargs *args)
3328 {
3329 	if (args->ops != args->iops) {
3330 		kfree(args->ops);
3331 		args->ops = args->iops;
3332 	}
3333 	kfree(args->tmpp);
3334 	args->tmpp = NULL;
3335 	while (args->to_free) {
3336 		struct tmpbuf *tb = args->to_free;
3337 		args->to_free = tb->next;
3338 		tb->release(tb->buf);
3339 		kfree(tb);
3340 	}
3341 }
3342 
3343 int
3344 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundargs *args)
3345 {
3346 	__be32 status;
3347 
3348 	args->p = p;
3349 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
3350 	args->pagelist = rqstp->rq_arg.pages;
3351 	args->pagelen = rqstp->rq_arg.page_len;
3352 	args->tmpp = NULL;
3353 	args->to_free = NULL;
3354 	args->ops = args->iops;
3355 	args->rqstp = rqstp;
3356 
3357 	status = nfsd4_decode_compound(args);
3358 	if (status) {
3359 		nfsd4_release_compoundargs(args);
3360 	}
3361 	return !status;
3362 }
3363 
3364 int
3365 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundres *resp)
3366 {
3367 	/*
3368 	 * All that remains is to write the tag and operation count...
3369 	 */
3370 	struct nfsd4_compound_state *cs = &resp->cstate;
3371 	struct kvec *iov;
3372 	p = resp->tagp;
3373 	*p++ = htonl(resp->taglen);
3374 	memcpy(p, resp->tag, resp->taglen);
3375 	p += XDR_QUADLEN(resp->taglen);
3376 	*p++ = htonl(resp->opcnt);
3377 
3378 	if (rqstp->rq_res.page_len)
3379 		iov = &rqstp->rq_res.tail[0];
3380 	else
3381 		iov = &rqstp->rq_res.head[0];
3382 	iov->iov_len = ((char*)resp->p) - (char*)iov->iov_base;
3383 	BUG_ON(iov->iov_len > PAGE_SIZE);
3384 	if (nfsd4_has_session(cs)) {
3385 		if (cs->status != nfserr_replay_cache) {
3386 			nfsd4_store_cache_entry(resp);
3387 			dprintk("%s: SET SLOT STATE TO AVAILABLE\n", __func__);
3388 			cs->slot->sl_inuse = false;
3389 		}
3390 		/* Renew the clientid on success and on replay */
3391 		release_session_client(cs->session);
3392 		nfsd4_put_session(cs->session);
3393 	}
3394 	return 1;
3395 }
3396 
3397 /*
3398  * Local variables:
3399  *  c-basic-offset: 8
3400  * End:
3401  */
3402