xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision b9ccfda2)
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/pagemap.h>
48 #include <linux/sunrpc/svcauth_gss.h>
49 
50 #include "idmap.h"
51 #include "acl.h"
52 #include "xdr4.h"
53 #include "vfs.h"
54 #include "state.h"
55 #include "cache.h"
56 
57 #define NFSDDBG_FACILITY		NFSDDBG_XDR
58 
59 /*
60  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
61  * directory in order to indicate to the client that a filesystem boundary is present
62  * We use a fixed fsid for a referral
63  */
64 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
65 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
66 
67 static __be32
68 check_filename(char *str, int len, __be32 err)
69 {
70 	int i;
71 
72 	if (len == 0)
73 		return nfserr_inval;
74 	if (isdotent(str, len))
75 		return err;
76 	for (i = 0; i < len; i++)
77 		if (str[i] == '/')
78 			return err;
79 	return 0;
80 }
81 
82 #define DECODE_HEAD				\
83 	__be32 *p;				\
84 	__be32 status
85 #define DECODE_TAIL				\
86 	status = 0;				\
87 out:						\
88 	return status;				\
89 xdr_error:					\
90 	dprintk("NFSD: xdr error (%s:%d)\n",	\
91 			__FILE__, __LINE__);	\
92 	status = nfserr_bad_xdr;		\
93 	goto out
94 
95 #define READ32(x)         (x) = ntohl(*p++)
96 #define READ64(x)         do {			\
97 	(x) = (u64)ntohl(*p++) << 32;		\
98 	(x) |= ntohl(*p++);			\
99 } while (0)
100 #define READTIME(x)       do {			\
101 	p++;					\
102 	(x) = ntohl(*p++);			\
103 	p++;					\
104 } while (0)
105 #define READMEM(x,nbytes) do {			\
106 	x = (char *)p;				\
107 	p += XDR_QUADLEN(nbytes);		\
108 } while (0)
109 #define SAVEMEM(x,nbytes) do {			\
110 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
111  		savemem(argp, p, nbytes) :	\
112  		(char *)p)) {			\
113 		dprintk("NFSD: xdr error (%s:%d)\n", \
114 				__FILE__, __LINE__); \
115 		goto xdr_error;			\
116 		}				\
117 	p += XDR_QUADLEN(nbytes);		\
118 } while (0)
119 #define COPYMEM(x,nbytes) do {			\
120 	memcpy((x), p, nbytes);			\
121 	p += XDR_QUADLEN(nbytes);		\
122 } while (0)
123 
124 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
125 #define READ_BUF(nbytes)  do {			\
126 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
127 		p = argp->p;			\
128 		argp->p += XDR_QUADLEN(nbytes);	\
129 	} else if (!(p = read_buf(argp, nbytes))) { \
130 		dprintk("NFSD: xdr error (%s:%d)\n", \
131 				__FILE__, __LINE__); \
132 		goto xdr_error;			\
133 	}					\
134 } while (0)
135 
136 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
137 {
138 	/* We want more bytes than seem to be available.
139 	 * Maybe we need a new page, maybe we have just run out
140 	 */
141 	unsigned int avail = (char *)argp->end - (char *)argp->p;
142 	__be32 *p;
143 	if (avail + argp->pagelen < nbytes)
144 		return NULL;
145 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
146 		return NULL;
147 	/* ok, we can do it with the current plus the next page */
148 	if (nbytes <= sizeof(argp->tmp))
149 		p = argp->tmp;
150 	else {
151 		kfree(argp->tmpp);
152 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
153 		if (!p)
154 			return NULL;
155 
156 	}
157 	/*
158 	 * The following memcpy is safe because read_buf is always
159 	 * called with nbytes > avail, and the two cases above both
160 	 * guarantee p points to at least nbytes bytes.
161 	 */
162 	memcpy(p, argp->p, avail);
163 	/* step to next page */
164 	argp->p = page_address(argp->pagelist[0]);
165 	argp->pagelist++;
166 	if (argp->pagelen < PAGE_SIZE) {
167 		argp->end = argp->p + (argp->pagelen>>2);
168 		argp->pagelen = 0;
169 	} else {
170 		argp->end = argp->p + (PAGE_SIZE>>2);
171 		argp->pagelen -= PAGE_SIZE;
172 	}
173 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
174 	argp->p += XDR_QUADLEN(nbytes - avail);
175 	return p;
176 }
177 
178 static int zero_clientid(clientid_t *clid)
179 {
180 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
181 }
182 
183 static int
184 defer_free(struct nfsd4_compoundargs *argp,
185 		void (*release)(const void *), void *p)
186 {
187 	struct tmpbuf *tb;
188 
189 	tb = kmalloc(sizeof(*tb), GFP_KERNEL);
190 	if (!tb)
191 		return -ENOMEM;
192 	tb->buf = p;
193 	tb->release = release;
194 	tb->next = argp->to_free;
195 	argp->to_free = tb;
196 	return 0;
197 }
198 
199 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
200 {
201 	if (p == argp->tmp) {
202 		p = kmemdup(argp->tmp, nbytes, GFP_KERNEL);
203 		if (!p)
204 			return NULL;
205 	} else {
206 		BUG_ON(p != argp->tmpp);
207 		argp->tmpp = NULL;
208 	}
209 	if (defer_free(argp, kfree, p)) {
210 		kfree(p);
211 		return NULL;
212 	} else
213 		return (char *)p;
214 }
215 
216 static __be32
217 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
218 {
219 	u32 bmlen;
220 	DECODE_HEAD;
221 
222 	bmval[0] = 0;
223 	bmval[1] = 0;
224 	bmval[2] = 0;
225 
226 	READ_BUF(4);
227 	READ32(bmlen);
228 	if (bmlen > 1000)
229 		goto xdr_error;
230 
231 	READ_BUF(bmlen << 2);
232 	if (bmlen > 0)
233 		READ32(bmval[0]);
234 	if (bmlen > 1)
235 		READ32(bmval[1]);
236 	if (bmlen > 2)
237 		READ32(bmval[2]);
238 
239 	DECODE_TAIL;
240 }
241 
242 static __be32
243 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
244 		   struct iattr *iattr, struct nfs4_acl **acl)
245 {
246 	int expected_len, len = 0;
247 	u32 dummy32;
248 	char *buf;
249 	int host_err;
250 
251 	DECODE_HEAD;
252 	iattr->ia_valid = 0;
253 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
254 		return status;
255 
256 	READ_BUF(4);
257 	READ32(expected_len);
258 
259 	if (bmval[0] & FATTR4_WORD0_SIZE) {
260 		READ_BUF(8);
261 		len += 8;
262 		READ64(iattr->ia_size);
263 		iattr->ia_valid |= ATTR_SIZE;
264 	}
265 	if (bmval[0] & FATTR4_WORD0_ACL) {
266 		int nace;
267 		struct nfs4_ace *ace;
268 
269 		READ_BUF(4); len += 4;
270 		READ32(nace);
271 
272 		if (nace > NFS4_ACL_MAX)
273 			return nfserr_resource;
274 
275 		*acl = nfs4_acl_new(nace);
276 		if (*acl == NULL) {
277 			host_err = -ENOMEM;
278 			goto out_nfserr;
279 		}
280 		defer_free(argp, kfree, *acl);
281 
282 		(*acl)->naces = nace;
283 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
284 			READ_BUF(16); len += 16;
285 			READ32(ace->type);
286 			READ32(ace->flag);
287 			READ32(ace->access_mask);
288 			READ32(dummy32);
289 			READ_BUF(dummy32);
290 			len += XDR_QUADLEN(dummy32) << 2;
291 			READMEM(buf, dummy32);
292 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
293 			status = nfs_ok;
294 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
295 				ace->who = 0;
296 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
297 				status = nfsd_map_name_to_gid(argp->rqstp,
298 						buf, dummy32, &ace->who);
299 			else
300 				status = nfsd_map_name_to_uid(argp->rqstp,
301 						buf, dummy32, &ace->who);
302 			if (status)
303 				return status;
304 		}
305 	} else
306 		*acl = NULL;
307 	if (bmval[1] & FATTR4_WORD1_MODE) {
308 		READ_BUF(4);
309 		len += 4;
310 		READ32(iattr->ia_mode);
311 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
312 		iattr->ia_valid |= ATTR_MODE;
313 	}
314 	if (bmval[1] & FATTR4_WORD1_OWNER) {
315 		READ_BUF(4);
316 		len += 4;
317 		READ32(dummy32);
318 		READ_BUF(dummy32);
319 		len += (XDR_QUADLEN(dummy32) << 2);
320 		READMEM(buf, dummy32);
321 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
322 			return status;
323 		iattr->ia_valid |= ATTR_UID;
324 	}
325 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
326 		READ_BUF(4);
327 		len += 4;
328 		READ32(dummy32);
329 		READ_BUF(dummy32);
330 		len += (XDR_QUADLEN(dummy32) << 2);
331 		READMEM(buf, dummy32);
332 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
333 			return status;
334 		iattr->ia_valid |= ATTR_GID;
335 	}
336 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
337 		READ_BUF(4);
338 		len += 4;
339 		READ32(dummy32);
340 		switch (dummy32) {
341 		case NFS4_SET_TO_CLIENT_TIME:
342 			/* We require the high 32 bits of 'seconds' to be 0, and we ignore
343 			   all 32 bits of 'nseconds'. */
344 			READ_BUF(12);
345 			len += 12;
346 			READ32(dummy32);
347 			if (dummy32)
348 				return nfserr_inval;
349 			READ32(iattr->ia_atime.tv_sec);
350 			READ32(iattr->ia_atime.tv_nsec);
351 			if (iattr->ia_atime.tv_nsec >= (u32)1000000000)
352 				return nfserr_inval;
353 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
354 			break;
355 		case NFS4_SET_TO_SERVER_TIME:
356 			iattr->ia_valid |= ATTR_ATIME;
357 			break;
358 		default:
359 			goto xdr_error;
360 		}
361 	}
362 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
363 		READ_BUF(4);
364 		len += 4;
365 		READ32(dummy32);
366 		switch (dummy32) {
367 		case NFS4_SET_TO_CLIENT_TIME:
368 			/* We require the high 32 bits of 'seconds' to be 0, and we ignore
369 			   all 32 bits of 'nseconds'. */
370 			READ_BUF(12);
371 			len += 12;
372 			READ32(dummy32);
373 			if (dummy32)
374 				return nfserr_inval;
375 			READ32(iattr->ia_mtime.tv_sec);
376 			READ32(iattr->ia_mtime.tv_nsec);
377 			if (iattr->ia_mtime.tv_nsec >= (u32)1000000000)
378 				return nfserr_inval;
379 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
380 			break;
381 		case NFS4_SET_TO_SERVER_TIME:
382 			iattr->ia_valid |= ATTR_MTIME;
383 			break;
384 		default:
385 			goto xdr_error;
386 		}
387 	}
388 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
389 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
390 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2)
391 		READ_BUF(expected_len - len);
392 	else if (len != expected_len)
393 		goto xdr_error;
394 
395 	DECODE_TAIL;
396 
397 out_nfserr:
398 	status = nfserrno(host_err);
399 	goto out;
400 }
401 
402 static __be32
403 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
404 {
405 	DECODE_HEAD;
406 
407 	READ_BUF(sizeof(stateid_t));
408 	READ32(sid->si_generation);
409 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
410 
411 	DECODE_TAIL;
412 }
413 
414 static __be32
415 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
416 {
417 	DECODE_HEAD;
418 
419 	READ_BUF(4);
420 	READ32(access->ac_req_access);
421 
422 	DECODE_TAIL;
423 }
424 
425 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
426 {
427 	DECODE_HEAD;
428 
429 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
430 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
431 	READ32(bcts->dir);
432 	/* XXX: skipping ctsa_use_conn_in_rdma_mode.  Perhaps Tom Tucker
433 	 * could help us figure out we should be using it. */
434 	DECODE_TAIL;
435 }
436 
437 static __be32
438 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
439 {
440 	DECODE_HEAD;
441 
442 	READ_BUF(4);
443 	READ32(close->cl_seqid);
444 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
445 
446 	DECODE_TAIL;
447 }
448 
449 
450 static __be32
451 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
452 {
453 	DECODE_HEAD;
454 
455 	READ_BUF(12);
456 	READ64(commit->co_offset);
457 	READ32(commit->co_count);
458 
459 	DECODE_TAIL;
460 }
461 
462 static __be32
463 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
464 {
465 	DECODE_HEAD;
466 
467 	READ_BUF(4);
468 	READ32(create->cr_type);
469 	switch (create->cr_type) {
470 	case NF4LNK:
471 		READ_BUF(4);
472 		READ32(create->cr_linklen);
473 		READ_BUF(create->cr_linklen);
474 		SAVEMEM(create->cr_linkname, create->cr_linklen);
475 		break;
476 	case NF4BLK:
477 	case NF4CHR:
478 		READ_BUF(8);
479 		READ32(create->cr_specdata1);
480 		READ32(create->cr_specdata2);
481 		break;
482 	case NF4SOCK:
483 	case NF4FIFO:
484 	case NF4DIR:
485 	default:
486 		break;
487 	}
488 
489 	READ_BUF(4);
490 	READ32(create->cr_namelen);
491 	READ_BUF(create->cr_namelen);
492 	SAVEMEM(create->cr_name, create->cr_namelen);
493 	if ((status = check_filename(create->cr_name, create->cr_namelen, nfserr_inval)))
494 		return status;
495 
496 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
497 				    &create->cr_acl);
498 	if (status)
499 		goto out;
500 
501 	DECODE_TAIL;
502 }
503 
504 static inline __be32
505 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
506 {
507 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
508 }
509 
510 static inline __be32
511 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
512 {
513 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
514 }
515 
516 static __be32
517 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
518 {
519 	DECODE_HEAD;
520 
521 	READ_BUF(4);
522 	READ32(link->li_namelen);
523 	READ_BUF(link->li_namelen);
524 	SAVEMEM(link->li_name, link->li_namelen);
525 	if ((status = check_filename(link->li_name, link->li_namelen, nfserr_inval)))
526 		return status;
527 
528 	DECODE_TAIL;
529 }
530 
531 static __be32
532 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
533 {
534 	DECODE_HEAD;
535 
536 	/*
537 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
538 	*/
539 	READ_BUF(28);
540 	READ32(lock->lk_type);
541 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
542 		goto xdr_error;
543 	READ32(lock->lk_reclaim);
544 	READ64(lock->lk_offset);
545 	READ64(lock->lk_length);
546 	READ32(lock->lk_is_new);
547 
548 	if (lock->lk_is_new) {
549 		READ_BUF(4);
550 		READ32(lock->lk_new_open_seqid);
551 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
552 		if (status)
553 			return status;
554 		READ_BUF(8 + sizeof(clientid_t));
555 		READ32(lock->lk_new_lock_seqid);
556 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
557 		READ32(lock->lk_new_owner.len);
558 		READ_BUF(lock->lk_new_owner.len);
559 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
560 	} else {
561 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
562 		if (status)
563 			return status;
564 		READ_BUF(4);
565 		READ32(lock->lk_old_lock_seqid);
566 	}
567 
568 	DECODE_TAIL;
569 }
570 
571 static __be32
572 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
573 {
574 	DECODE_HEAD;
575 
576 	READ_BUF(32);
577 	READ32(lockt->lt_type);
578 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
579 		goto xdr_error;
580 	READ64(lockt->lt_offset);
581 	READ64(lockt->lt_length);
582 	COPYMEM(&lockt->lt_clientid, 8);
583 	READ32(lockt->lt_owner.len);
584 	READ_BUF(lockt->lt_owner.len);
585 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
586 
587 	DECODE_TAIL;
588 }
589 
590 static __be32
591 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
592 {
593 	DECODE_HEAD;
594 
595 	READ_BUF(8);
596 	READ32(locku->lu_type);
597 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
598 		goto xdr_error;
599 	READ32(locku->lu_seqid);
600 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
601 	if (status)
602 		return status;
603 	READ_BUF(16);
604 	READ64(locku->lu_offset);
605 	READ64(locku->lu_length);
606 
607 	DECODE_TAIL;
608 }
609 
610 static __be32
611 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
612 {
613 	DECODE_HEAD;
614 
615 	READ_BUF(4);
616 	READ32(lookup->lo_len);
617 	READ_BUF(lookup->lo_len);
618 	SAVEMEM(lookup->lo_name, lookup->lo_len);
619 	if ((status = check_filename(lookup->lo_name, lookup->lo_len, nfserr_noent)))
620 		return status;
621 
622 	DECODE_TAIL;
623 }
624 
625 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
626 {
627 	__be32 *p;
628 	u32 w;
629 
630 	READ_BUF(4);
631 	READ32(w);
632 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
633 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
634 	if (deleg_when)
635 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
636 
637 	switch (w & NFS4_SHARE_ACCESS_MASK) {
638 	case NFS4_SHARE_ACCESS_READ:
639 	case NFS4_SHARE_ACCESS_WRITE:
640 	case NFS4_SHARE_ACCESS_BOTH:
641 		break;
642 	default:
643 		return nfserr_bad_xdr;
644 	}
645 	w &= ~NFS4_SHARE_ACCESS_MASK;
646 	if (!w)
647 		return nfs_ok;
648 	if (!argp->minorversion)
649 		return nfserr_bad_xdr;
650 	switch (w & NFS4_SHARE_WANT_MASK) {
651 	case NFS4_SHARE_WANT_NO_PREFERENCE:
652 	case NFS4_SHARE_WANT_READ_DELEG:
653 	case NFS4_SHARE_WANT_WRITE_DELEG:
654 	case NFS4_SHARE_WANT_ANY_DELEG:
655 	case NFS4_SHARE_WANT_NO_DELEG:
656 	case NFS4_SHARE_WANT_CANCEL:
657 		break;
658 	default:
659 		return nfserr_bad_xdr;
660 	}
661 	w &= ~NFS4_SHARE_WANT_MASK;
662 	if (!w)
663 		return nfs_ok;
664 
665 	if (!deleg_when)	/* open_downgrade */
666 		return nfserr_inval;
667 	switch (w) {
668 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
669 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
670 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
671 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
672 		return nfs_ok;
673 	}
674 xdr_error:
675 	return nfserr_bad_xdr;
676 }
677 
678 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
679 {
680 	__be32 *p;
681 
682 	READ_BUF(4);
683 	READ32(*x);
684 	/* Note: unlinke access bits, deny bits may be zero. */
685 	if (*x & ~NFS4_SHARE_DENY_BOTH)
686 		return nfserr_bad_xdr;
687 	return nfs_ok;
688 xdr_error:
689 	return nfserr_bad_xdr;
690 }
691 
692 static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
693 {
694 	__be32 *p;
695 
696 	READ_BUF(4);
697 	READ32(o->len);
698 
699 	if (o->len == 0 || o->len > NFS4_OPAQUE_LIMIT)
700 		return nfserr_bad_xdr;
701 
702 	READ_BUF(o->len);
703 	SAVEMEM(o->data, o->len);
704 	return nfs_ok;
705 xdr_error:
706 	return nfserr_bad_xdr;
707 }
708 
709 static __be32
710 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
711 {
712 	DECODE_HEAD;
713 	u32 dummy;
714 
715 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
716 	open->op_iattr.ia_valid = 0;
717 	open->op_openowner = NULL;
718 
719 	/* seqid, share_access, share_deny, clientid, ownerlen */
720 	READ_BUF(4);
721 	READ32(open->op_seqid);
722 	/* decode, yet ignore deleg_when until supported */
723 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
724 					   &open->op_deleg_want, &dummy);
725 	if (status)
726 		goto xdr_error;
727 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
728 	if (status)
729 		goto xdr_error;
730 	READ_BUF(sizeof(clientid_t));
731 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
732 	status = nfsd4_decode_opaque(argp, &open->op_owner);
733 	if (status)
734 		goto xdr_error;
735 	READ_BUF(4);
736 	READ32(open->op_create);
737 	switch (open->op_create) {
738 	case NFS4_OPEN_NOCREATE:
739 		break;
740 	case NFS4_OPEN_CREATE:
741 		READ_BUF(4);
742 		READ32(open->op_createmode);
743 		switch (open->op_createmode) {
744 		case NFS4_CREATE_UNCHECKED:
745 		case NFS4_CREATE_GUARDED:
746 			status = nfsd4_decode_fattr(argp, open->op_bmval,
747 				&open->op_iattr, &open->op_acl);
748 			if (status)
749 				goto out;
750 			break;
751 		case NFS4_CREATE_EXCLUSIVE:
752 			READ_BUF(NFS4_VERIFIER_SIZE);
753 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
754 			break;
755 		case NFS4_CREATE_EXCLUSIVE4_1:
756 			if (argp->minorversion < 1)
757 				goto xdr_error;
758 			READ_BUF(NFS4_VERIFIER_SIZE);
759 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
760 			status = nfsd4_decode_fattr(argp, open->op_bmval,
761 				&open->op_iattr, &open->op_acl);
762 			if (status)
763 				goto out;
764 			break;
765 		default:
766 			goto xdr_error;
767 		}
768 		break;
769 	default:
770 		goto xdr_error;
771 	}
772 
773 	/* open_claim */
774 	READ_BUF(4);
775 	READ32(open->op_claim_type);
776 	switch (open->op_claim_type) {
777 	case NFS4_OPEN_CLAIM_NULL:
778 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
779 		READ_BUF(4);
780 		READ32(open->op_fname.len);
781 		READ_BUF(open->op_fname.len);
782 		SAVEMEM(open->op_fname.data, open->op_fname.len);
783 		if ((status = check_filename(open->op_fname.data, open->op_fname.len, nfserr_inval)))
784 			return status;
785 		break;
786 	case NFS4_OPEN_CLAIM_PREVIOUS:
787 		READ_BUF(4);
788 		READ32(open->op_delegate_type);
789 		break;
790 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
791 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
792 		if (status)
793 			return status;
794 		READ_BUF(4);
795 		READ32(open->op_fname.len);
796 		READ_BUF(open->op_fname.len);
797 		SAVEMEM(open->op_fname.data, open->op_fname.len);
798 		if ((status = check_filename(open->op_fname.data, open->op_fname.len, nfserr_inval)))
799 			return status;
800 		break;
801 	case NFS4_OPEN_CLAIM_FH:
802 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
803 		if (argp->minorversion < 1)
804 			goto xdr_error;
805 		/* void */
806 		break;
807 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
808 		if (argp->minorversion < 1)
809 			goto xdr_error;
810 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
811 		if (status)
812 			return status;
813 		break;
814 	default:
815 		goto xdr_error;
816 	}
817 
818 	DECODE_TAIL;
819 }
820 
821 static __be32
822 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
823 {
824 	DECODE_HEAD;
825 
826 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
827 	if (status)
828 		return status;
829 	READ_BUF(4);
830 	READ32(open_conf->oc_seqid);
831 
832 	DECODE_TAIL;
833 }
834 
835 static __be32
836 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
837 {
838 	DECODE_HEAD;
839 
840 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
841 	if (status)
842 		return status;
843 	READ_BUF(4);
844 	READ32(open_down->od_seqid);
845 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
846 					   &open_down->od_deleg_want, NULL);
847 	if (status)
848 		return status;
849 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
850 	if (status)
851 		return status;
852 	DECODE_TAIL;
853 }
854 
855 static __be32
856 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
857 {
858 	DECODE_HEAD;
859 
860 	READ_BUF(4);
861 	READ32(putfh->pf_fhlen);
862 	if (putfh->pf_fhlen > NFS4_FHSIZE)
863 		goto xdr_error;
864 	READ_BUF(putfh->pf_fhlen);
865 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
866 
867 	DECODE_TAIL;
868 }
869 
870 static __be32
871 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
872 {
873 	DECODE_HEAD;
874 
875 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
876 	if (status)
877 		return status;
878 	READ_BUF(12);
879 	READ64(read->rd_offset);
880 	READ32(read->rd_length);
881 
882 	DECODE_TAIL;
883 }
884 
885 static __be32
886 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
887 {
888 	DECODE_HEAD;
889 
890 	READ_BUF(24);
891 	READ64(readdir->rd_cookie);
892 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
893 	READ32(readdir->rd_dircount);    /* just in case you needed a useless field... */
894 	READ32(readdir->rd_maxcount);
895 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
896 		goto out;
897 
898 	DECODE_TAIL;
899 }
900 
901 static __be32
902 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
903 {
904 	DECODE_HEAD;
905 
906 	READ_BUF(4);
907 	READ32(remove->rm_namelen);
908 	READ_BUF(remove->rm_namelen);
909 	SAVEMEM(remove->rm_name, remove->rm_namelen);
910 	if ((status = check_filename(remove->rm_name, remove->rm_namelen, nfserr_noent)))
911 		return status;
912 
913 	DECODE_TAIL;
914 }
915 
916 static __be32
917 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
918 {
919 	DECODE_HEAD;
920 
921 	READ_BUF(4);
922 	READ32(rename->rn_snamelen);
923 	READ_BUF(rename->rn_snamelen + 4);
924 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
925 	READ32(rename->rn_tnamelen);
926 	READ_BUF(rename->rn_tnamelen);
927 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
928 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen, nfserr_noent)))
929 		return status;
930 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen, nfserr_inval)))
931 		return status;
932 
933 	DECODE_TAIL;
934 }
935 
936 static __be32
937 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
938 {
939 	DECODE_HEAD;
940 
941 	READ_BUF(sizeof(clientid_t));
942 	COPYMEM(clientid, sizeof(clientid_t));
943 
944 	DECODE_TAIL;
945 }
946 
947 static __be32
948 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
949 		     struct nfsd4_secinfo *secinfo)
950 {
951 	DECODE_HEAD;
952 
953 	READ_BUF(4);
954 	READ32(secinfo->si_namelen);
955 	READ_BUF(secinfo->si_namelen);
956 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
957 	status = check_filename(secinfo->si_name, secinfo->si_namelen,
958 								nfserr_noent);
959 	if (status)
960 		return status;
961 	DECODE_TAIL;
962 }
963 
964 static __be32
965 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
966 		     struct nfsd4_secinfo_no_name *sin)
967 {
968 	DECODE_HEAD;
969 
970 	READ_BUF(4);
971 	READ32(sin->sin_style);
972 	DECODE_TAIL;
973 }
974 
975 static __be32
976 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
977 {
978 	__be32 status;
979 
980 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
981 	if (status)
982 		return status;
983 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
984 				  &setattr->sa_acl);
985 }
986 
987 static __be32
988 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
989 {
990 	DECODE_HEAD;
991 
992 	READ_BUF(NFS4_VERIFIER_SIZE);
993 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
994 
995 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
996 	if (status)
997 		return nfserr_bad_xdr;
998 	READ_BUF(8);
999 	READ32(setclientid->se_callback_prog);
1000 	READ32(setclientid->se_callback_netid_len);
1001 
1002 	READ_BUF(setclientid->se_callback_netid_len + 4);
1003 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1004 	READ32(setclientid->se_callback_addr_len);
1005 
1006 	READ_BUF(setclientid->se_callback_addr_len + 4);
1007 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1008 	READ32(setclientid->se_callback_ident);
1009 
1010 	DECODE_TAIL;
1011 }
1012 
1013 static __be32
1014 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1015 {
1016 	DECODE_HEAD;
1017 
1018 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1019 	COPYMEM(&scd_c->sc_clientid, 8);
1020 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1021 
1022 	DECODE_TAIL;
1023 }
1024 
1025 /* Also used for NVERIFY */
1026 static __be32
1027 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1028 {
1029 #if 0
1030 	struct nfsd4_compoundargs save = {
1031 		.p = argp->p,
1032 		.end = argp->end,
1033 		.rqstp = argp->rqstp,
1034 	};
1035 	u32             ve_bmval[2];
1036 	struct iattr    ve_iattr;           /* request */
1037 	struct nfs4_acl *ve_acl;            /* request */
1038 #endif
1039 	DECODE_HEAD;
1040 
1041 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1042 		goto out;
1043 
1044 	/* For convenience's sake, we compare raw xdr'd attributes in
1045 	 * nfsd4_proc_verify; however we still decode here just to return
1046 	 * correct error in case of bad xdr. */
1047 #if 0
1048 	status = nfsd4_decode_fattr(ve_bmval, &ve_iattr, &ve_acl);
1049 	if (status == nfserr_inval) {
1050 		status = nfserrno(status);
1051 		goto out;
1052 	}
1053 #endif
1054 	READ_BUF(4);
1055 	READ32(verify->ve_attrlen);
1056 	READ_BUF(verify->ve_attrlen);
1057 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1058 
1059 	DECODE_TAIL;
1060 }
1061 
1062 static __be32
1063 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1064 {
1065 	int avail;
1066 	int v;
1067 	int len;
1068 	DECODE_HEAD;
1069 
1070 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1071 	if (status)
1072 		return status;
1073 	READ_BUF(16);
1074 	READ64(write->wr_offset);
1075 	READ32(write->wr_stable_how);
1076 	if (write->wr_stable_how > 2)
1077 		goto xdr_error;
1078 	READ32(write->wr_buflen);
1079 
1080 	/* Sorry .. no magic macros for this.. *
1081 	 * READ_BUF(write->wr_buflen);
1082 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1083 	 */
1084 	avail = (char*)argp->end - (char*)argp->p;
1085 	if (avail + argp->pagelen < write->wr_buflen) {
1086 		dprintk("NFSD: xdr error (%s:%d)\n",
1087 				__FILE__, __LINE__);
1088 		goto xdr_error;
1089 	}
1090 	argp->rqstp->rq_vec[0].iov_base = p;
1091 	argp->rqstp->rq_vec[0].iov_len = avail;
1092 	v = 0;
1093 	len = write->wr_buflen;
1094 	while (len > argp->rqstp->rq_vec[v].iov_len) {
1095 		len -= argp->rqstp->rq_vec[v].iov_len;
1096 		v++;
1097 		argp->rqstp->rq_vec[v].iov_base = page_address(argp->pagelist[0]);
1098 		argp->pagelist++;
1099 		if (argp->pagelen >= PAGE_SIZE) {
1100 			argp->rqstp->rq_vec[v].iov_len = PAGE_SIZE;
1101 			argp->pagelen -= PAGE_SIZE;
1102 		} else {
1103 			argp->rqstp->rq_vec[v].iov_len = argp->pagelen;
1104 			argp->pagelen -= len;
1105 		}
1106 	}
1107 	argp->end = (__be32*) (argp->rqstp->rq_vec[v].iov_base + argp->rqstp->rq_vec[v].iov_len);
1108 	argp->p = (__be32*)  (argp->rqstp->rq_vec[v].iov_base + (XDR_QUADLEN(len) << 2));
1109 	argp->rqstp->rq_vec[v].iov_len = len;
1110 	write->wr_vlen = v+1;
1111 
1112 	DECODE_TAIL;
1113 }
1114 
1115 static __be32
1116 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1117 {
1118 	DECODE_HEAD;
1119 
1120 	READ_BUF(12);
1121 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1122 	READ32(rlockowner->rl_owner.len);
1123 	READ_BUF(rlockowner->rl_owner.len);
1124 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1125 
1126 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1127 		return nfserr_inval;
1128 	DECODE_TAIL;
1129 }
1130 
1131 static __be32
1132 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1133 			 struct nfsd4_exchange_id *exid)
1134 {
1135 	int dummy, tmp;
1136 	DECODE_HEAD;
1137 
1138 	READ_BUF(NFS4_VERIFIER_SIZE);
1139 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1140 
1141 	status = nfsd4_decode_opaque(argp, &exid->clname);
1142 	if (status)
1143 		return nfserr_bad_xdr;
1144 
1145 	READ_BUF(4);
1146 	READ32(exid->flags);
1147 
1148 	/* Ignore state_protect4_a */
1149 	READ_BUF(4);
1150 	READ32(exid->spa_how);
1151 	switch (exid->spa_how) {
1152 	case SP4_NONE:
1153 		break;
1154 	case SP4_MACH_CRED:
1155 		/* spo_must_enforce */
1156 		READ_BUF(4);
1157 		READ32(dummy);
1158 		READ_BUF(dummy * 4);
1159 		p += dummy;
1160 
1161 		/* spo_must_allow */
1162 		READ_BUF(4);
1163 		READ32(dummy);
1164 		READ_BUF(dummy * 4);
1165 		p += dummy;
1166 		break;
1167 	case SP4_SSV:
1168 		/* ssp_ops */
1169 		READ_BUF(4);
1170 		READ32(dummy);
1171 		READ_BUF(dummy * 4);
1172 		p += dummy;
1173 
1174 		READ_BUF(4);
1175 		READ32(dummy);
1176 		READ_BUF(dummy * 4);
1177 		p += dummy;
1178 
1179 		/* ssp_hash_algs<> */
1180 		READ_BUF(4);
1181 		READ32(tmp);
1182 		while (tmp--) {
1183 			READ_BUF(4);
1184 			READ32(dummy);
1185 			READ_BUF(dummy);
1186 			p += XDR_QUADLEN(dummy);
1187 		}
1188 
1189 		/* ssp_encr_algs<> */
1190 		READ_BUF(4);
1191 		READ32(tmp);
1192 		while (tmp--) {
1193 			READ_BUF(4);
1194 			READ32(dummy);
1195 			READ_BUF(dummy);
1196 			p += XDR_QUADLEN(dummy);
1197 		}
1198 
1199 		/* ssp_window and ssp_num_gss_handles */
1200 		READ_BUF(8);
1201 		READ32(dummy);
1202 		READ32(dummy);
1203 		break;
1204 	default:
1205 		goto xdr_error;
1206 	}
1207 
1208 	/* Ignore Implementation ID */
1209 	READ_BUF(4);    /* nfs_impl_id4 array length */
1210 	READ32(dummy);
1211 
1212 	if (dummy > 1)
1213 		goto xdr_error;
1214 
1215 	if (dummy == 1) {
1216 		/* nii_domain */
1217 		READ_BUF(4);
1218 		READ32(dummy);
1219 		READ_BUF(dummy);
1220 		p += XDR_QUADLEN(dummy);
1221 
1222 		/* nii_name */
1223 		READ_BUF(4);
1224 		READ32(dummy);
1225 		READ_BUF(dummy);
1226 		p += XDR_QUADLEN(dummy);
1227 
1228 		/* nii_date */
1229 		READ_BUF(12);
1230 		p += 3;
1231 	}
1232 	DECODE_TAIL;
1233 }
1234 
1235 static __be32
1236 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1237 			    struct nfsd4_create_session *sess)
1238 {
1239 	DECODE_HEAD;
1240 
1241 	u32 dummy;
1242 	char *machine_name;
1243 	int i;
1244 	int nr_secflavs;
1245 
1246 	READ_BUF(16);
1247 	COPYMEM(&sess->clientid, 8);
1248 	READ32(sess->seqid);
1249 	READ32(sess->flags);
1250 
1251 	/* Fore channel attrs */
1252 	READ_BUF(28);
1253 	READ32(dummy); /* headerpadsz is always 0 */
1254 	READ32(sess->fore_channel.maxreq_sz);
1255 	READ32(sess->fore_channel.maxresp_sz);
1256 	READ32(sess->fore_channel.maxresp_cached);
1257 	READ32(sess->fore_channel.maxops);
1258 	READ32(sess->fore_channel.maxreqs);
1259 	READ32(sess->fore_channel.nr_rdma_attrs);
1260 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1261 		READ_BUF(4);
1262 		READ32(sess->fore_channel.rdma_attrs);
1263 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1264 		dprintk("Too many fore channel attr bitmaps!\n");
1265 		goto xdr_error;
1266 	}
1267 
1268 	/* Back channel attrs */
1269 	READ_BUF(28);
1270 	READ32(dummy); /* headerpadsz is always 0 */
1271 	READ32(sess->back_channel.maxreq_sz);
1272 	READ32(sess->back_channel.maxresp_sz);
1273 	READ32(sess->back_channel.maxresp_cached);
1274 	READ32(sess->back_channel.maxops);
1275 	READ32(sess->back_channel.maxreqs);
1276 	READ32(sess->back_channel.nr_rdma_attrs);
1277 	if (sess->back_channel.nr_rdma_attrs == 1) {
1278 		READ_BUF(4);
1279 		READ32(sess->back_channel.rdma_attrs);
1280 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1281 		dprintk("Too many back channel attr bitmaps!\n");
1282 		goto xdr_error;
1283 	}
1284 
1285 	READ_BUF(8);
1286 	READ32(sess->callback_prog);
1287 
1288 	/* callback_sec_params4 */
1289 	READ32(nr_secflavs);
1290 	for (i = 0; i < nr_secflavs; ++i) {
1291 		READ_BUF(4);
1292 		READ32(dummy);
1293 		switch (dummy) {
1294 		case RPC_AUTH_NULL:
1295 			/* Nothing to read */
1296 			break;
1297 		case RPC_AUTH_UNIX:
1298 			READ_BUF(8);
1299 			/* stamp */
1300 			READ32(dummy);
1301 
1302 			/* machine name */
1303 			READ32(dummy);
1304 			READ_BUF(dummy);
1305 			SAVEMEM(machine_name, dummy);
1306 
1307 			/* uid, gid */
1308 			READ_BUF(8);
1309 			READ32(sess->uid);
1310 			READ32(sess->gid);
1311 
1312 			/* more gids */
1313 			READ_BUF(4);
1314 			READ32(dummy);
1315 			READ_BUF(dummy * 4);
1316 			break;
1317 		case RPC_AUTH_GSS:
1318 			dprintk("RPC_AUTH_GSS callback secflavor "
1319 				"not supported!\n");
1320 			READ_BUF(8);
1321 			/* gcbp_service */
1322 			READ32(dummy);
1323 			/* gcbp_handle_from_server */
1324 			READ32(dummy);
1325 			READ_BUF(dummy);
1326 			p += XDR_QUADLEN(dummy);
1327 			/* gcbp_handle_from_client */
1328 			READ_BUF(4);
1329 			READ32(dummy);
1330 			READ_BUF(dummy);
1331 			break;
1332 		default:
1333 			dprintk("Illegal callback secflavor\n");
1334 			return nfserr_inval;
1335 		}
1336 	}
1337 	DECODE_TAIL;
1338 }
1339 
1340 static __be32
1341 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1342 			     struct nfsd4_destroy_session *destroy_session)
1343 {
1344 	DECODE_HEAD;
1345 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1346 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1347 
1348 	DECODE_TAIL;
1349 }
1350 
1351 static __be32
1352 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1353 			  struct nfsd4_free_stateid *free_stateid)
1354 {
1355 	DECODE_HEAD;
1356 
1357 	READ_BUF(sizeof(stateid_t));
1358 	READ32(free_stateid->fr_stateid.si_generation);
1359 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1360 
1361 	DECODE_TAIL;
1362 }
1363 
1364 static __be32
1365 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1366 		      struct nfsd4_sequence *seq)
1367 {
1368 	DECODE_HEAD;
1369 
1370 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1371 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1372 	READ32(seq->seqid);
1373 	READ32(seq->slotid);
1374 	READ32(seq->maxslots);
1375 	READ32(seq->cachethis);
1376 
1377 	DECODE_TAIL;
1378 }
1379 
1380 static __be32
1381 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1382 {
1383 	int i;
1384 	__be32 *p, status;
1385 	struct nfsd4_test_stateid_id *stateid;
1386 
1387 	READ_BUF(4);
1388 	test_stateid->ts_num_ids = ntohl(*p++);
1389 
1390 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1391 
1392 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1393 		stateid = kmalloc(sizeof(struct nfsd4_test_stateid_id), GFP_KERNEL);
1394 		if (!stateid) {
1395 			status = nfserrno(-ENOMEM);
1396 			goto out;
1397 		}
1398 
1399 		defer_free(argp, kfree, stateid);
1400 		INIT_LIST_HEAD(&stateid->ts_id_list);
1401 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1402 
1403 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1404 		if (status)
1405 			goto out;
1406 	}
1407 
1408 	status = 0;
1409 out:
1410 	return status;
1411 xdr_error:
1412 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1413 	status = nfserr_bad_xdr;
1414 	goto out;
1415 }
1416 
1417 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1418 {
1419 	DECODE_HEAD;
1420 
1421 	READ_BUF(8);
1422 	COPYMEM(&dc->clientid, 8);
1423 
1424 	DECODE_TAIL;
1425 }
1426 
1427 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1428 {
1429 	DECODE_HEAD;
1430 
1431 	READ_BUF(4);
1432 	READ32(rc->rca_one_fs);
1433 
1434 	DECODE_TAIL;
1435 }
1436 
1437 static __be32
1438 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1439 {
1440 	return nfs_ok;
1441 }
1442 
1443 static __be32
1444 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1445 {
1446 	return nfserr_notsupp;
1447 }
1448 
1449 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1450 
1451 static nfsd4_dec nfsd4_dec_ops[] = {
1452 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1453 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1454 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1455 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1456 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1457 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1458 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1459 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1460 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1461 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1462 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1463 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1464 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1465 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1466 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1467 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1468 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1469 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1470 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1471 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1472 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_noop,
1473 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1474 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1475 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1476 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1477 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1478 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1479 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1480 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1481 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1482 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1483 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1484 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1485 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1486 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1487 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1488 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1489 };
1490 
1491 static nfsd4_dec nfsd41_dec_ops[] = {
1492 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1493 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1494 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1495 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1496 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1497 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1498 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1499 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1500 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1501 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1502 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1503 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1504 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1505 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1506 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1507 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1508 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1509 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_notsupp,
1510 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1511 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1512 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_notsupp,
1513 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1514 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1515 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1516 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1517 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1518 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1519 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_notsupp,
1520 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1521 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1522 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1523 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1524 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_notsupp,
1525 	[OP_SETCLIENTID_CONFIRM]= (nfsd4_dec)nfsd4_decode_notsupp,
1526 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1527 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1528 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_notsupp,
1529 
1530 	/* new operations for NFSv4.1 */
1531 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_notsupp,
1532 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1533 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1534 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1535 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1536 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
1537 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1538 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1539 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1540 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1541 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1542 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1543 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1544 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1545 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1546 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
1547 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1548 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
1549 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1550 };
1551 
1552 struct nfsd4_minorversion_ops {
1553 	nfsd4_dec *decoders;
1554 	int nops;
1555 };
1556 
1557 static struct nfsd4_minorversion_ops nfsd4_minorversion[] = {
1558 	[0] = { nfsd4_dec_ops, ARRAY_SIZE(nfsd4_dec_ops) },
1559 	[1] = { nfsd41_dec_ops, ARRAY_SIZE(nfsd41_dec_ops) },
1560 };
1561 
1562 static __be32
1563 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1564 {
1565 	DECODE_HEAD;
1566 	struct nfsd4_op *op;
1567 	struct nfsd4_minorversion_ops *ops;
1568 	bool cachethis = false;
1569 	int i;
1570 
1571 	/*
1572 	 * XXX: According to spec, we should check the tag
1573 	 * for UTF-8 compliance.  I'm postponing this for
1574 	 * now because it seems that some clients do use
1575 	 * binary tags.
1576 	 */
1577 	READ_BUF(4);
1578 	READ32(argp->taglen);
1579 	READ_BUF(argp->taglen + 8);
1580 	SAVEMEM(argp->tag, argp->taglen);
1581 	READ32(argp->minorversion);
1582 	READ32(argp->opcnt);
1583 
1584 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1585 		goto xdr_error;
1586 	if (argp->opcnt > 100)
1587 		goto xdr_error;
1588 
1589 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1590 		argp->ops = kmalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1591 		if (!argp->ops) {
1592 			argp->ops = argp->iops;
1593 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1594 			goto xdr_error;
1595 		}
1596 	}
1597 
1598 	if (argp->minorversion >= ARRAY_SIZE(nfsd4_minorversion))
1599 		argp->opcnt = 0;
1600 
1601 	ops = &nfsd4_minorversion[argp->minorversion];
1602 	for (i = 0; i < argp->opcnt; i++) {
1603 		op = &argp->ops[i];
1604 		op->replay = NULL;
1605 
1606 		/*
1607 		 * We can't use READ_BUF() here because we need to handle
1608 		 * a missing opcode as an OP_WRITE + 1. So we need to check
1609 		 * to see if we're truly at the end of our buffer or if there
1610 		 * is another page we need to flip to.
1611 		 */
1612 
1613 		if (argp->p == argp->end) {
1614 			if (argp->pagelen < 4) {
1615 				/* There isn't an opcode still on the wire */
1616 				op->opnum = OP_WRITE + 1;
1617 				op->status = nfserr_bad_xdr;
1618 				argp->opcnt = i+1;
1619 				break;
1620 			}
1621 
1622 			/*
1623 			 * False alarm. We just hit a page boundary, but there
1624 			 * is still data available.  Move pointer across page
1625 			 * boundary.  *snip from READ_BUF*
1626 			 */
1627 			argp->p = page_address(argp->pagelist[0]);
1628 			argp->pagelist++;
1629 			if (argp->pagelen < PAGE_SIZE) {
1630 				argp->end = argp->p + (argp->pagelen>>2);
1631 				argp->pagelen = 0;
1632 			} else {
1633 				argp->end = argp->p + (PAGE_SIZE>>2);
1634 				argp->pagelen -= PAGE_SIZE;
1635 			}
1636 		}
1637 		op->opnum = ntohl(*argp->p++);
1638 
1639 		if (op->opnum >= FIRST_NFS4_OP && op->opnum <= LAST_NFS4_OP)
1640 			op->status = ops->decoders[op->opnum](argp, &op->u);
1641 		else {
1642 			op->opnum = OP_ILLEGAL;
1643 			op->status = nfserr_op_illegal;
1644 		}
1645 
1646 		if (op->status) {
1647 			argp->opcnt = i+1;
1648 			break;
1649 		}
1650 		/*
1651 		 * We'll try to cache the result in the DRC if any one
1652 		 * op in the compound wants to be cached:
1653 		 */
1654 		cachethis |= nfsd4_cache_this_op(op);
1655 	}
1656 	/* Sessions make the DRC unnecessary: */
1657 	if (argp->minorversion)
1658 		cachethis = false;
1659 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1660 
1661 	DECODE_TAIL;
1662 }
1663 
1664 #define WRITE32(n)               *p++ = htonl(n)
1665 #define WRITE64(n)               do {				\
1666 	*p++ = htonl((u32)((n) >> 32));				\
1667 	*p++ = htonl((u32)(n));					\
1668 } while (0)
1669 #define WRITEMEM(ptr,nbytes)     do { if (nbytes > 0) {		\
1670 	*(p + XDR_QUADLEN(nbytes) -1) = 0;                      \
1671 	memcpy(p, ptr, nbytes);					\
1672 	p += XDR_QUADLEN(nbytes);				\
1673 }} while (0)
1674 
1675 static void write32(__be32 **p, u32 n)
1676 {
1677 	*(*p)++ = htonl(n);
1678 }
1679 
1680 static void write64(__be32 **p, u64 n)
1681 {
1682 	write32(p, (n >> 32));
1683 	write32(p, (u32)n);
1684 }
1685 
1686 static void write_change(__be32 **p, struct kstat *stat, struct inode *inode)
1687 {
1688 	if (IS_I_VERSION(inode)) {
1689 		write64(p, inode->i_version);
1690 	} else {
1691 		write32(p, stat->ctime.tv_sec);
1692 		write32(p, stat->ctime.tv_nsec);
1693 	}
1694 }
1695 
1696 static void write_cinfo(__be32 **p, struct nfsd4_change_info *c)
1697 {
1698 	write32(p, c->atomic);
1699 	if (c->change_supported) {
1700 		write64(p, c->before_change);
1701 		write64(p, c->after_change);
1702 	} else {
1703 		write32(p, c->before_ctime_sec);
1704 		write32(p, c->before_ctime_nsec);
1705 		write32(p, c->after_ctime_sec);
1706 		write32(p, c->after_ctime_nsec);
1707 	}
1708 }
1709 
1710 #define RESERVE_SPACE(nbytes)	do {				\
1711 	p = resp->p;						\
1712 	BUG_ON(p + XDR_QUADLEN(nbytes) > resp->end);		\
1713 } while (0)
1714 #define ADJUST_ARGS()		resp->p = p
1715 
1716 /*
1717  * Header routine to setup seqid operation replay cache
1718  */
1719 #define ENCODE_SEQID_OP_HEAD					\
1720 	__be32 *save;						\
1721 								\
1722 	save = resp->p;
1723 
1724 /*
1725  * Routine for encoding the result of a "seqid-mutating" NFSv4 operation.  This
1726  * is where sequence id's are incremented, and the replay cache is filled.
1727  * Note that we increment sequence id's here, at the last moment, so we're sure
1728  * we know whether the error to be returned is a sequence id mutating error.
1729  */
1730 
1731 static void encode_seqid_op_tail(struct nfsd4_compoundres *resp, __be32 *save, __be32 nfserr)
1732 {
1733 	struct nfs4_stateowner *stateowner = resp->cstate.replay_owner;
1734 
1735 	if (seqid_mutating_err(ntohl(nfserr)) && stateowner) {
1736 		stateowner->so_seqid++;
1737 		stateowner->so_replay.rp_status = nfserr;
1738 		stateowner->so_replay.rp_buflen =
1739 			  (char *)resp->p - (char *)save;
1740 		memcpy(stateowner->so_replay.rp_buf, save,
1741 			stateowner->so_replay.rp_buflen);
1742 		nfsd4_purge_closed_stateid(stateowner);
1743 	}
1744 }
1745 
1746 /* Encode as an array of strings the string given with components
1747  * separated @sep, escaped with esc_enter and esc_exit.
1748  */
1749 static __be32 nfsd4_encode_components_esc(char sep, char *components,
1750 				   __be32 **pp, int *buflen,
1751 				   char esc_enter, char esc_exit)
1752 {
1753 	__be32 *p = *pp;
1754 	__be32 *countp = p;
1755 	int strlen, count=0;
1756 	char *str, *end, *next;
1757 
1758 	dprintk("nfsd4_encode_components(%s)\n", components);
1759 	if ((*buflen -= 4) < 0)
1760 		return nfserr_resource;
1761 	WRITE32(0); /* We will fill this in with @count later */
1762 	end = str = components;
1763 	while (*end) {
1764 		bool found_esc = false;
1765 
1766 		/* try to parse as esc_start, ..., esc_end, sep */
1767 		if (*str == esc_enter) {
1768 			for (; *end && (*end != esc_exit); end++)
1769 				/* find esc_exit or end of string */;
1770 			next = end + 1;
1771 			if (*end && (!*next || *next == sep)) {
1772 				str++;
1773 				found_esc = true;
1774 			}
1775 		}
1776 
1777 		if (!found_esc)
1778 			for (; *end && (*end != sep); end++)
1779 				/* find sep or end of string */;
1780 
1781 		strlen = end - str;
1782 		if (strlen) {
1783 			if ((*buflen -= ((XDR_QUADLEN(strlen) << 2) + 4)) < 0)
1784 				return nfserr_resource;
1785 			WRITE32(strlen);
1786 			WRITEMEM(str, strlen);
1787 			count++;
1788 		}
1789 		else
1790 			end++;
1791 		str = end;
1792 	}
1793 	*pp = p;
1794 	p = countp;
1795 	WRITE32(count);
1796 	return 0;
1797 }
1798 
1799 /* Encode as an array of strings the string given with components
1800  * separated @sep.
1801  */
1802 static __be32 nfsd4_encode_components(char sep, char *components,
1803 				   __be32 **pp, int *buflen)
1804 {
1805 	return nfsd4_encode_components_esc(sep, components, pp, buflen, 0, 0);
1806 }
1807 
1808 /*
1809  * encode a location element of a fs_locations structure
1810  */
1811 static __be32 nfsd4_encode_fs_location4(struct nfsd4_fs_location *location,
1812 				    __be32 **pp, int *buflen)
1813 {
1814 	__be32 status;
1815 	__be32 *p = *pp;
1816 
1817 	status = nfsd4_encode_components_esc(':', location->hosts, &p, buflen,
1818 						'[', ']');
1819 	if (status)
1820 		return status;
1821 	status = nfsd4_encode_components('/', location->path, &p, buflen);
1822 	if (status)
1823 		return status;
1824 	*pp = p;
1825 	return 0;
1826 }
1827 
1828 /*
1829  * Encode a path in RFC3530 'pathname4' format
1830  */
1831 static __be32 nfsd4_encode_path(const struct path *root,
1832 		const struct path *path, __be32 **pp, int *buflen)
1833 {
1834 	struct path cur = {
1835 		.mnt = path->mnt,
1836 		.dentry = path->dentry,
1837 	};
1838 	__be32 *p = *pp;
1839 	struct dentry **components = NULL;
1840 	unsigned int ncomponents = 0;
1841 	__be32 err = nfserr_jukebox;
1842 
1843 	dprintk("nfsd4_encode_components(");
1844 
1845 	path_get(&cur);
1846 	/* First walk the path up to the nfsd root, and store the
1847 	 * dentries/path components in an array.
1848 	 */
1849 	for (;;) {
1850 		if (cur.dentry == root->dentry && cur.mnt == root->mnt)
1851 			break;
1852 		if (cur.dentry == cur.mnt->mnt_root) {
1853 			if (follow_up(&cur))
1854 				continue;
1855 			goto out_free;
1856 		}
1857 		if ((ncomponents & 15) == 0) {
1858 			struct dentry **new;
1859 			new = krealloc(components,
1860 					sizeof(*new) * (ncomponents + 16),
1861 					GFP_KERNEL);
1862 			if (!new)
1863 				goto out_free;
1864 			components = new;
1865 		}
1866 		components[ncomponents++] = cur.dentry;
1867 		cur.dentry = dget_parent(cur.dentry);
1868 	}
1869 
1870 	*buflen -= 4;
1871 	if (*buflen < 0)
1872 		goto out_free;
1873 	WRITE32(ncomponents);
1874 
1875 	while (ncomponents) {
1876 		struct dentry *dentry = components[ncomponents - 1];
1877 		unsigned int len = dentry->d_name.len;
1878 
1879 		*buflen -= 4 + (XDR_QUADLEN(len) << 2);
1880 		if (*buflen < 0)
1881 			goto out_free;
1882 		WRITE32(len);
1883 		WRITEMEM(dentry->d_name.name, len);
1884 		dprintk("/%s", dentry->d_name.name);
1885 		dput(dentry);
1886 		ncomponents--;
1887 	}
1888 
1889 	*pp = p;
1890 	err = 0;
1891 out_free:
1892 	dprintk(")\n");
1893 	while (ncomponents)
1894 		dput(components[--ncomponents]);
1895 	kfree(components);
1896 	path_put(&cur);
1897 	return err;
1898 }
1899 
1900 static __be32 nfsd4_encode_fsloc_fsroot(struct svc_rqst *rqstp,
1901 		const struct path *path, __be32 **pp, int *buflen)
1902 {
1903 	struct svc_export *exp_ps;
1904 	__be32 res;
1905 
1906 	exp_ps = rqst_find_fsidzero_export(rqstp);
1907 	if (IS_ERR(exp_ps))
1908 		return nfserrno(PTR_ERR(exp_ps));
1909 	res = nfsd4_encode_path(&exp_ps->ex_path, path, pp, buflen);
1910 	exp_put(exp_ps);
1911 	return res;
1912 }
1913 
1914 /*
1915  *  encode a fs_locations structure
1916  */
1917 static __be32 nfsd4_encode_fs_locations(struct svc_rqst *rqstp,
1918 				     struct svc_export *exp,
1919 				     __be32 **pp, int *buflen)
1920 {
1921 	__be32 status;
1922 	int i;
1923 	__be32 *p = *pp;
1924 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
1925 
1926 	status = nfsd4_encode_fsloc_fsroot(rqstp, &exp->ex_path, &p, buflen);
1927 	if (status)
1928 		return status;
1929 	if ((*buflen -= 4) < 0)
1930 		return nfserr_resource;
1931 	WRITE32(fslocs->locations_count);
1932 	for (i=0; i<fslocs->locations_count; i++) {
1933 		status = nfsd4_encode_fs_location4(&fslocs->locations[i],
1934 						   &p, buflen);
1935 		if (status)
1936 			return status;
1937 	}
1938 	*pp = p;
1939 	return 0;
1940 }
1941 
1942 static u32 nfs4_file_type(umode_t mode)
1943 {
1944 	switch (mode & S_IFMT) {
1945 	case S_IFIFO:	return NF4FIFO;
1946 	case S_IFCHR:	return NF4CHR;
1947 	case S_IFDIR:	return NF4DIR;
1948 	case S_IFBLK:	return NF4BLK;
1949 	case S_IFLNK:	return NF4LNK;
1950 	case S_IFREG:	return NF4REG;
1951 	case S_IFSOCK:	return NF4SOCK;
1952 	default:	return NF4BAD;
1953 	};
1954 }
1955 
1956 static __be32
1957 nfsd4_encode_name(struct svc_rqst *rqstp, int whotype, uid_t id, int group,
1958 			__be32 **p, int *buflen)
1959 {
1960 	int status;
1961 
1962 	if (*buflen < (XDR_QUADLEN(IDMAP_NAMESZ) << 2) + 4)
1963 		return nfserr_resource;
1964 	if (whotype != NFS4_ACL_WHO_NAMED)
1965 		status = nfs4_acl_write_who(whotype, (u8 *)(*p + 1));
1966 	else if (group)
1967 		status = nfsd_map_gid_to_name(rqstp, id, (u8 *)(*p + 1));
1968 	else
1969 		status = nfsd_map_uid_to_name(rqstp, id, (u8 *)(*p + 1));
1970 	if (status < 0)
1971 		return nfserrno(status);
1972 	*p = xdr_encode_opaque(*p, NULL, status);
1973 	*buflen -= (XDR_QUADLEN(status) << 2) + 4;
1974 	BUG_ON(*buflen < 0);
1975 	return 0;
1976 }
1977 
1978 static inline __be32
1979 nfsd4_encode_user(struct svc_rqst *rqstp, uid_t uid, __be32 **p, int *buflen)
1980 {
1981 	return nfsd4_encode_name(rqstp, NFS4_ACL_WHO_NAMED, uid, 0, p, buflen);
1982 }
1983 
1984 static inline __be32
1985 nfsd4_encode_group(struct svc_rqst *rqstp, uid_t gid, __be32 **p, int *buflen)
1986 {
1987 	return nfsd4_encode_name(rqstp, NFS4_ACL_WHO_NAMED, gid, 1, p, buflen);
1988 }
1989 
1990 static inline __be32
1991 nfsd4_encode_aclname(struct svc_rqst *rqstp, int whotype, uid_t id, int group,
1992 		__be32 **p, int *buflen)
1993 {
1994 	return nfsd4_encode_name(rqstp, whotype, id, group, p, buflen);
1995 }
1996 
1997 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
1998 			      FATTR4_WORD0_RDATTR_ERROR)
1999 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2000 
2001 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *rdattr_err)
2002 {
2003 	/* As per referral draft:  */
2004 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2005 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2006 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2007 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2008 			*rdattr_err = NFSERR_MOVED;
2009 		else
2010 			return nfserr_moved;
2011 	}
2012 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2013 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2014 	return 0;
2015 }
2016 
2017 /*
2018  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2019  * ourselves.
2020  *
2021  * @countp is the buffer size in _words_; upon successful return this becomes
2022  * replaced with the number of words written.
2023  */
2024 __be32
2025 nfsd4_encode_fattr(struct svc_fh *fhp, struct svc_export *exp,
2026 		struct dentry *dentry, __be32 *buffer, int *countp, u32 *bmval,
2027 		struct svc_rqst *rqstp, int ignore_crossmnt)
2028 {
2029 	u32 bmval0 = bmval[0];
2030 	u32 bmval1 = bmval[1];
2031 	u32 bmval2 = bmval[2];
2032 	struct kstat stat;
2033 	struct svc_fh tempfh;
2034 	struct kstatfs statfs;
2035 	int buflen = *countp << 2;
2036 	__be32 *attrlenp;
2037 	u32 dummy;
2038 	u64 dummy64;
2039 	u32 rdattr_err = 0;
2040 	__be32 *p = buffer;
2041 	__be32 status;
2042 	int err;
2043 	int aclsupport = 0;
2044 	struct nfs4_acl *acl = NULL;
2045 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2046 	u32 minorversion = resp->cstate.minorversion;
2047 	struct path path = {
2048 		.mnt	= exp->ex_path.mnt,
2049 		.dentry	= dentry,
2050 	};
2051 
2052 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2053 	BUG_ON(bmval0 & ~nfsd_suppattrs0(minorversion));
2054 	BUG_ON(bmval1 & ~nfsd_suppattrs1(minorversion));
2055 	BUG_ON(bmval2 & ~nfsd_suppattrs2(minorversion));
2056 
2057 	if (exp->ex_fslocs.migrated) {
2058 		BUG_ON(bmval[2]);
2059 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &rdattr_err);
2060 		if (status)
2061 			goto out;
2062 	}
2063 
2064 	err = vfs_getattr(exp->ex_path.mnt, dentry, &stat);
2065 	if (err)
2066 		goto out_nfserr;
2067 	if ((bmval0 & (FATTR4_WORD0_FILES_FREE | FATTR4_WORD0_FILES_TOTAL |
2068 			FATTR4_WORD0_MAXNAME)) ||
2069 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2070 		       FATTR4_WORD1_SPACE_TOTAL))) {
2071 		err = vfs_statfs(&path, &statfs);
2072 		if (err)
2073 			goto out_nfserr;
2074 	}
2075 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2076 		fh_init(&tempfh, NFS4_FHSIZE);
2077 		status = fh_compose(&tempfh, exp, dentry, NULL);
2078 		if (status)
2079 			goto out;
2080 		fhp = &tempfh;
2081 	}
2082 	if (bmval0 & (FATTR4_WORD0_ACL | FATTR4_WORD0_ACLSUPPORT
2083 			| FATTR4_WORD0_SUPPORTED_ATTRS)) {
2084 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2085 		aclsupport = (err == 0);
2086 		if (bmval0 & FATTR4_WORD0_ACL) {
2087 			if (err == -EOPNOTSUPP)
2088 				bmval0 &= ~FATTR4_WORD0_ACL;
2089 			else if (err == -EINVAL) {
2090 				status = nfserr_attrnotsupp;
2091 				goto out;
2092 			} else if (err != 0)
2093 				goto out_nfserr;
2094 		}
2095 	}
2096 
2097 	if (bmval2) {
2098 		if ((buflen -= 16) < 0)
2099 			goto out_resource;
2100 		WRITE32(3);
2101 		WRITE32(bmval0);
2102 		WRITE32(bmval1);
2103 		WRITE32(bmval2);
2104 	} else if (bmval1) {
2105 		if ((buflen -= 12) < 0)
2106 			goto out_resource;
2107 		WRITE32(2);
2108 		WRITE32(bmval0);
2109 		WRITE32(bmval1);
2110 	} else {
2111 		if ((buflen -= 8) < 0)
2112 			goto out_resource;
2113 		WRITE32(1);
2114 		WRITE32(bmval0);
2115 	}
2116 	attrlenp = p++;                /* to be backfilled later */
2117 
2118 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2119 		u32 word0 = nfsd_suppattrs0(minorversion);
2120 		u32 word1 = nfsd_suppattrs1(minorversion);
2121 		u32 word2 = nfsd_suppattrs2(minorversion);
2122 
2123 		if (!aclsupport)
2124 			word0 &= ~FATTR4_WORD0_ACL;
2125 		if (!word2) {
2126 			if ((buflen -= 12) < 0)
2127 				goto out_resource;
2128 			WRITE32(2);
2129 			WRITE32(word0);
2130 			WRITE32(word1);
2131 		} else {
2132 			if ((buflen -= 16) < 0)
2133 				goto out_resource;
2134 			WRITE32(3);
2135 			WRITE32(word0);
2136 			WRITE32(word1);
2137 			WRITE32(word2);
2138 		}
2139 	}
2140 	if (bmval0 & FATTR4_WORD0_TYPE) {
2141 		if ((buflen -= 4) < 0)
2142 			goto out_resource;
2143 		dummy = nfs4_file_type(stat.mode);
2144 		if (dummy == NF4BAD)
2145 			goto out_serverfault;
2146 		WRITE32(dummy);
2147 	}
2148 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2149 		if ((buflen -= 4) < 0)
2150 			goto out_resource;
2151 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2152 			WRITE32(NFS4_FH_PERSISTENT);
2153 		else
2154 			WRITE32(NFS4_FH_PERSISTENT|NFS4_FH_VOL_RENAME);
2155 	}
2156 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2157 		if ((buflen -= 8) < 0)
2158 			goto out_resource;
2159 		write_change(&p, &stat, dentry->d_inode);
2160 	}
2161 	if (bmval0 & FATTR4_WORD0_SIZE) {
2162 		if ((buflen -= 8) < 0)
2163 			goto out_resource;
2164 		WRITE64(stat.size);
2165 	}
2166 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2167 		if ((buflen -= 4) < 0)
2168 			goto out_resource;
2169 		WRITE32(1);
2170 	}
2171 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2172 		if ((buflen -= 4) < 0)
2173 			goto out_resource;
2174 		WRITE32(1);
2175 	}
2176 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2177 		if ((buflen -= 4) < 0)
2178 			goto out_resource;
2179 		WRITE32(0);
2180 	}
2181 	if (bmval0 & FATTR4_WORD0_FSID) {
2182 		if ((buflen -= 16) < 0)
2183 			goto out_resource;
2184 		if (exp->ex_fslocs.migrated) {
2185 			WRITE64(NFS4_REFERRAL_FSID_MAJOR);
2186 			WRITE64(NFS4_REFERRAL_FSID_MINOR);
2187 		} else switch(fsid_source(fhp)) {
2188 		case FSIDSOURCE_FSID:
2189 			WRITE64((u64)exp->ex_fsid);
2190 			WRITE64((u64)0);
2191 			break;
2192 		case FSIDSOURCE_DEV:
2193 			WRITE32(0);
2194 			WRITE32(MAJOR(stat.dev));
2195 			WRITE32(0);
2196 			WRITE32(MINOR(stat.dev));
2197 			break;
2198 		case FSIDSOURCE_UUID:
2199 			WRITEMEM(exp->ex_uuid, 16);
2200 			break;
2201 		}
2202 	}
2203 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2204 		if ((buflen -= 4) < 0)
2205 			goto out_resource;
2206 		WRITE32(0);
2207 	}
2208 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2209 		if ((buflen -= 4) < 0)
2210 			goto out_resource;
2211 		WRITE32(nfsd4_lease);
2212 	}
2213 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2214 		if ((buflen -= 4) < 0)
2215 			goto out_resource;
2216 		WRITE32(rdattr_err);
2217 	}
2218 	if (bmval0 & FATTR4_WORD0_ACL) {
2219 		struct nfs4_ace *ace;
2220 
2221 		if (acl == NULL) {
2222 			if ((buflen -= 4) < 0)
2223 				goto out_resource;
2224 
2225 			WRITE32(0);
2226 			goto out_acl;
2227 		}
2228 		if ((buflen -= 4) < 0)
2229 			goto out_resource;
2230 		WRITE32(acl->naces);
2231 
2232 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2233 			if ((buflen -= 4*3) < 0)
2234 				goto out_resource;
2235 			WRITE32(ace->type);
2236 			WRITE32(ace->flag);
2237 			WRITE32(ace->access_mask & NFS4_ACE_MASK_ALL);
2238 			status = nfsd4_encode_aclname(rqstp, ace->whotype,
2239 				ace->who, ace->flag & NFS4_ACE_IDENTIFIER_GROUP,
2240 				&p, &buflen);
2241 			if (status == nfserr_resource)
2242 				goto out_resource;
2243 			if (status)
2244 				goto out;
2245 		}
2246 	}
2247 out_acl:
2248 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2249 		if ((buflen -= 4) < 0)
2250 			goto out_resource;
2251 		WRITE32(aclsupport ?
2252 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2253 	}
2254 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2255 		if ((buflen -= 4) < 0)
2256 			goto out_resource;
2257 		WRITE32(1);
2258 	}
2259 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2260 		if ((buflen -= 4) < 0)
2261 			goto out_resource;
2262 		WRITE32(1);
2263 	}
2264 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2265 		if ((buflen -= 4) < 0)
2266 			goto out_resource;
2267 		WRITE32(1);
2268 	}
2269 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2270 		if ((buflen -= 4) < 0)
2271 			goto out_resource;
2272 		WRITE32(1);
2273 	}
2274 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2275 		buflen -= (XDR_QUADLEN(fhp->fh_handle.fh_size) << 2) + 4;
2276 		if (buflen < 0)
2277 			goto out_resource;
2278 		WRITE32(fhp->fh_handle.fh_size);
2279 		WRITEMEM(&fhp->fh_handle.fh_base, fhp->fh_handle.fh_size);
2280 	}
2281 	if (bmval0 & FATTR4_WORD0_FILEID) {
2282 		if ((buflen -= 8) < 0)
2283 			goto out_resource;
2284 		WRITE64(stat.ino);
2285 	}
2286 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2287 		if ((buflen -= 8) < 0)
2288 			goto out_resource;
2289 		WRITE64((u64) statfs.f_ffree);
2290 	}
2291 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2292 		if ((buflen -= 8) < 0)
2293 			goto out_resource;
2294 		WRITE64((u64) statfs.f_ffree);
2295 	}
2296 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2297 		if ((buflen -= 8) < 0)
2298 			goto out_resource;
2299 		WRITE64((u64) statfs.f_files);
2300 	}
2301 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2302 		status = nfsd4_encode_fs_locations(rqstp, exp, &p, &buflen);
2303 		if (status == nfserr_resource)
2304 			goto out_resource;
2305 		if (status)
2306 			goto out;
2307 	}
2308 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2309 		if ((buflen -= 4) < 0)
2310 			goto out_resource;
2311 		WRITE32(1);
2312 	}
2313 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2314 		if ((buflen -= 8) < 0)
2315 			goto out_resource;
2316 		WRITE64(~(u64)0);
2317 	}
2318 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2319 		if ((buflen -= 4) < 0)
2320 			goto out_resource;
2321 		WRITE32(255);
2322 	}
2323 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2324 		if ((buflen -= 4) < 0)
2325 			goto out_resource;
2326 		WRITE32(statfs.f_namelen);
2327 	}
2328 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2329 		if ((buflen -= 8) < 0)
2330 			goto out_resource;
2331 		WRITE64((u64) svc_max_payload(rqstp));
2332 	}
2333 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2334 		if ((buflen -= 8) < 0)
2335 			goto out_resource;
2336 		WRITE64((u64) svc_max_payload(rqstp));
2337 	}
2338 	if (bmval1 & FATTR4_WORD1_MODE) {
2339 		if ((buflen -= 4) < 0)
2340 			goto out_resource;
2341 		WRITE32(stat.mode & S_IALLUGO);
2342 	}
2343 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2344 		if ((buflen -= 4) < 0)
2345 			goto out_resource;
2346 		WRITE32(1);
2347 	}
2348 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2349 		if ((buflen -= 4) < 0)
2350 			goto out_resource;
2351 		WRITE32(stat.nlink);
2352 	}
2353 	if (bmval1 & FATTR4_WORD1_OWNER) {
2354 		status = nfsd4_encode_user(rqstp, stat.uid, &p, &buflen);
2355 		if (status == nfserr_resource)
2356 			goto out_resource;
2357 		if (status)
2358 			goto out;
2359 	}
2360 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2361 		status = nfsd4_encode_group(rqstp, stat.gid, &p, &buflen);
2362 		if (status == nfserr_resource)
2363 			goto out_resource;
2364 		if (status)
2365 			goto out;
2366 	}
2367 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2368 		if ((buflen -= 8) < 0)
2369 			goto out_resource;
2370 		WRITE32((u32) MAJOR(stat.rdev));
2371 		WRITE32((u32) MINOR(stat.rdev));
2372 	}
2373 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2374 		if ((buflen -= 8) < 0)
2375 			goto out_resource;
2376 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2377 		WRITE64(dummy64);
2378 	}
2379 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2380 		if ((buflen -= 8) < 0)
2381 			goto out_resource;
2382 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2383 		WRITE64(dummy64);
2384 	}
2385 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2386 		if ((buflen -= 8) < 0)
2387 			goto out_resource;
2388 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2389 		WRITE64(dummy64);
2390 	}
2391 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2392 		if ((buflen -= 8) < 0)
2393 			goto out_resource;
2394 		dummy64 = (u64)stat.blocks << 9;
2395 		WRITE64(dummy64);
2396 	}
2397 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2398 		if ((buflen -= 12) < 0)
2399 			goto out_resource;
2400 		WRITE32(0);
2401 		WRITE32(stat.atime.tv_sec);
2402 		WRITE32(stat.atime.tv_nsec);
2403 	}
2404 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2405 		if ((buflen -= 12) < 0)
2406 			goto out_resource;
2407 		WRITE32(0);
2408 		WRITE32(1);
2409 		WRITE32(0);
2410 	}
2411 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2412 		if ((buflen -= 12) < 0)
2413 			goto out_resource;
2414 		WRITE32(0);
2415 		WRITE32(stat.ctime.tv_sec);
2416 		WRITE32(stat.ctime.tv_nsec);
2417 	}
2418 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2419 		if ((buflen -= 12) < 0)
2420 			goto out_resource;
2421 		WRITE32(0);
2422 		WRITE32(stat.mtime.tv_sec);
2423 		WRITE32(stat.mtime.tv_nsec);
2424 	}
2425 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2426 		if ((buflen -= 8) < 0)
2427                 	goto out_resource;
2428 		/*
2429 		 * Get parent's attributes if not ignoring crossmount
2430 		 * and this is the root of a cross-mounted filesystem.
2431 		 */
2432 		if (ignore_crossmnt == 0 &&
2433 		    dentry == exp->ex_path.mnt->mnt_root) {
2434 			struct path path = exp->ex_path;
2435 			path_get(&path);
2436 			while (follow_up(&path)) {
2437 				if (path.dentry != path.mnt->mnt_root)
2438 					break;
2439 			}
2440 			err = vfs_getattr(path.mnt, path.dentry, &stat);
2441 			path_put(&path);
2442 			if (err)
2443 				goto out_nfserr;
2444 		}
2445 		WRITE64(stat.ino);
2446 	}
2447 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2448 		WRITE32(3);
2449 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD0);
2450 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD1);
2451 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD2);
2452 	}
2453 
2454 	*attrlenp = htonl((char *)p - (char *)attrlenp - 4);
2455 	*countp = p - buffer;
2456 	status = nfs_ok;
2457 
2458 out:
2459 	kfree(acl);
2460 	if (fhp == &tempfh)
2461 		fh_put(&tempfh);
2462 	return status;
2463 out_nfserr:
2464 	status = nfserrno(err);
2465 	goto out;
2466 out_resource:
2467 	*countp = 0;
2468 	status = nfserr_resource;
2469 	goto out;
2470 out_serverfault:
2471 	status = nfserr_serverfault;
2472 	goto out;
2473 }
2474 
2475 static inline int attributes_need_mount(u32 *bmval)
2476 {
2477 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2478 		return 1;
2479 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2480 		return 1;
2481 	return 0;
2482 }
2483 
2484 static __be32
2485 nfsd4_encode_dirent_fattr(struct nfsd4_readdir *cd,
2486 		const char *name, int namlen, __be32 *p, int *buflen)
2487 {
2488 	struct svc_export *exp = cd->rd_fhp->fh_export;
2489 	struct dentry *dentry;
2490 	__be32 nfserr;
2491 	int ignore_crossmnt = 0;
2492 
2493 	dentry = lookup_one_len(name, cd->rd_fhp->fh_dentry, namlen);
2494 	if (IS_ERR(dentry))
2495 		return nfserrno(PTR_ERR(dentry));
2496 	if (!dentry->d_inode) {
2497 		/*
2498 		 * nfsd_buffered_readdir drops the i_mutex between
2499 		 * readdir and calling this callback, leaving a window
2500 		 * where this directory entry could have gone away.
2501 		 */
2502 		dput(dentry);
2503 		return nfserr_noent;
2504 	}
2505 
2506 	exp_get(exp);
2507 	/*
2508 	 * In the case of a mountpoint, the client may be asking for
2509 	 * attributes that are only properties of the underlying filesystem
2510 	 * as opposed to the cross-mounted file system. In such a case,
2511 	 * we will not follow the cross mount and will fill the attribtutes
2512 	 * directly from the mountpoint dentry.
2513 	 */
2514 	if (nfsd_mountpoint(dentry, exp)) {
2515 		int err;
2516 
2517 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
2518 				&& !attributes_need_mount(cd->rd_bmval)) {
2519 			ignore_crossmnt = 1;
2520 			goto out_encode;
2521 		}
2522 		/*
2523 		 * Why the heck aren't we just using nfsd_lookup??
2524 		 * Different "."/".." handling?  Something else?
2525 		 * At least, add a comment here to explain....
2526 		 */
2527 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
2528 		if (err) {
2529 			nfserr = nfserrno(err);
2530 			goto out_put;
2531 		}
2532 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
2533 		if (nfserr)
2534 			goto out_put;
2535 
2536 	}
2537 out_encode:
2538 	nfserr = nfsd4_encode_fattr(NULL, exp, dentry, p, buflen, cd->rd_bmval,
2539 					cd->rd_rqstp, ignore_crossmnt);
2540 out_put:
2541 	dput(dentry);
2542 	exp_put(exp);
2543 	return nfserr;
2544 }
2545 
2546 static __be32 *
2547 nfsd4_encode_rdattr_error(__be32 *p, int buflen, __be32 nfserr)
2548 {
2549 	__be32 *attrlenp;
2550 
2551 	if (buflen < 6)
2552 		return NULL;
2553 	*p++ = htonl(2);
2554 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
2555 	*p++ = htonl(0);			 /* bmval1 */
2556 
2557 	attrlenp = p++;
2558 	*p++ = nfserr;       /* no htonl */
2559 	*attrlenp = htonl((char *)p - (char *)attrlenp - 4);
2560 	return p;
2561 }
2562 
2563 static int
2564 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
2565 		    loff_t offset, u64 ino, unsigned int d_type)
2566 {
2567 	struct readdir_cd *ccd = ccdv;
2568 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
2569 	int buflen;
2570 	__be32 *p = cd->buffer;
2571 	__be32 *cookiep;
2572 	__be32 nfserr = nfserr_toosmall;
2573 
2574 	/* In nfsv4, "." and ".." never make it onto the wire.. */
2575 	if (name && isdotent(name, namlen)) {
2576 		cd->common.err = nfs_ok;
2577 		return 0;
2578 	}
2579 
2580 	if (cd->offset)
2581 		xdr_encode_hyper(cd->offset, (u64) offset);
2582 
2583 	buflen = cd->buflen - 4 - XDR_QUADLEN(namlen);
2584 	if (buflen < 0)
2585 		goto fail;
2586 
2587 	*p++ = xdr_one;                             /* mark entry present */
2588 	cookiep = p;
2589 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
2590 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
2591 
2592 	nfserr = nfsd4_encode_dirent_fattr(cd, name, namlen, p, &buflen);
2593 	switch (nfserr) {
2594 	case nfs_ok:
2595 		p += buflen;
2596 		break;
2597 	case nfserr_resource:
2598 		nfserr = nfserr_toosmall;
2599 		goto fail;
2600 	case nfserr_noent:
2601 		goto skip_entry;
2602 	default:
2603 		/*
2604 		 * If the client requested the RDATTR_ERROR attribute,
2605 		 * we stuff the error code into this attribute
2606 		 * and continue.  If this attribute was not requested,
2607 		 * then in accordance with the spec, we fail the
2608 		 * entire READDIR operation(!)
2609 		 */
2610 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
2611 			goto fail;
2612 		p = nfsd4_encode_rdattr_error(p, buflen, nfserr);
2613 		if (p == NULL) {
2614 			nfserr = nfserr_toosmall;
2615 			goto fail;
2616 		}
2617 	}
2618 	cd->buflen -= (p - cd->buffer);
2619 	cd->buffer = p;
2620 	cd->offset = cookiep;
2621 skip_entry:
2622 	cd->common.err = nfs_ok;
2623 	return 0;
2624 fail:
2625 	cd->common.err = nfserr;
2626 	return -EINVAL;
2627 }
2628 
2629 static void
2630 nfsd4_encode_stateid(struct nfsd4_compoundres *resp, stateid_t *sid)
2631 {
2632 	__be32 *p;
2633 
2634 	RESERVE_SPACE(sizeof(stateid_t));
2635 	WRITE32(sid->si_generation);
2636 	WRITEMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
2637 	ADJUST_ARGS();
2638 }
2639 
2640 static __be32
2641 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
2642 {
2643 	__be32 *p;
2644 
2645 	if (!nfserr) {
2646 		RESERVE_SPACE(8);
2647 		WRITE32(access->ac_supported);
2648 		WRITE32(access->ac_resp_access);
2649 		ADJUST_ARGS();
2650 	}
2651 	return nfserr;
2652 }
2653 
2654 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
2655 {
2656 	__be32 *p;
2657 
2658 	if (!nfserr) {
2659 		RESERVE_SPACE(NFS4_MAX_SESSIONID_LEN + 8);
2660 		WRITEMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
2661 		WRITE32(bcts->dir);
2662 		/* XXX: ? */
2663 		WRITE32(0);
2664 		ADJUST_ARGS();
2665 	}
2666 	return nfserr;
2667 }
2668 
2669 static __be32
2670 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
2671 {
2672 	ENCODE_SEQID_OP_HEAD;
2673 
2674 	if (!nfserr)
2675 		nfsd4_encode_stateid(resp, &close->cl_stateid);
2676 
2677 	encode_seqid_op_tail(resp, save, nfserr);
2678 	return nfserr;
2679 }
2680 
2681 
2682 static __be32
2683 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
2684 {
2685 	__be32 *p;
2686 
2687 	if (!nfserr) {
2688 		RESERVE_SPACE(NFS4_VERIFIER_SIZE);
2689 		WRITEMEM(commit->co_verf.data, NFS4_VERIFIER_SIZE);
2690 		ADJUST_ARGS();
2691 	}
2692 	return nfserr;
2693 }
2694 
2695 static __be32
2696 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
2697 {
2698 	__be32 *p;
2699 
2700 	if (!nfserr) {
2701 		RESERVE_SPACE(32);
2702 		write_cinfo(&p, &create->cr_cinfo);
2703 		WRITE32(2);
2704 		WRITE32(create->cr_bmval[0]);
2705 		WRITE32(create->cr_bmval[1]);
2706 		ADJUST_ARGS();
2707 	}
2708 	return nfserr;
2709 }
2710 
2711 static __be32
2712 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
2713 {
2714 	struct svc_fh *fhp = getattr->ga_fhp;
2715 	int buflen;
2716 
2717 	if (nfserr)
2718 		return nfserr;
2719 
2720 	buflen = resp->end - resp->p - (COMPOUND_ERR_SLACK_SPACE >> 2);
2721 	nfserr = nfsd4_encode_fattr(fhp, fhp->fh_export, fhp->fh_dentry,
2722 				    resp->p, &buflen, getattr->ga_bmval,
2723 				    resp->rqstp, 0);
2724 	if (!nfserr)
2725 		resp->p += buflen;
2726 	return nfserr;
2727 }
2728 
2729 static __be32
2730 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
2731 {
2732 	struct svc_fh *fhp = *fhpp;
2733 	unsigned int len;
2734 	__be32 *p;
2735 
2736 	if (!nfserr) {
2737 		len = fhp->fh_handle.fh_size;
2738 		RESERVE_SPACE(len + 4);
2739 		WRITE32(len);
2740 		WRITEMEM(&fhp->fh_handle.fh_base, len);
2741 		ADJUST_ARGS();
2742 	}
2743 	return nfserr;
2744 }
2745 
2746 /*
2747 * Including all fields other than the name, a LOCK4denied structure requires
2748 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
2749 */
2750 static void
2751 nfsd4_encode_lock_denied(struct nfsd4_compoundres *resp, struct nfsd4_lock_denied *ld)
2752 {
2753 	struct xdr_netobj *conf = &ld->ld_owner;
2754 	__be32 *p;
2755 
2756 	RESERVE_SPACE(32 + XDR_LEN(conf->len));
2757 	WRITE64(ld->ld_start);
2758 	WRITE64(ld->ld_length);
2759 	WRITE32(ld->ld_type);
2760 	if (conf->len) {
2761 		WRITEMEM(&ld->ld_clientid, 8);
2762 		WRITE32(conf->len);
2763 		WRITEMEM(conf->data, conf->len);
2764 		kfree(conf->data);
2765 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
2766 		WRITE64((u64)0); /* clientid */
2767 		WRITE32(0); /* length of owner name */
2768 	}
2769 	ADJUST_ARGS();
2770 }
2771 
2772 static __be32
2773 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
2774 {
2775 	ENCODE_SEQID_OP_HEAD;
2776 
2777 	if (!nfserr)
2778 		nfsd4_encode_stateid(resp, &lock->lk_resp_stateid);
2779 	else if (nfserr == nfserr_denied)
2780 		nfsd4_encode_lock_denied(resp, &lock->lk_denied);
2781 
2782 	encode_seqid_op_tail(resp, save, nfserr);
2783 	return nfserr;
2784 }
2785 
2786 static __be32
2787 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
2788 {
2789 	if (nfserr == nfserr_denied)
2790 		nfsd4_encode_lock_denied(resp, &lockt->lt_denied);
2791 	return nfserr;
2792 }
2793 
2794 static __be32
2795 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
2796 {
2797 	ENCODE_SEQID_OP_HEAD;
2798 
2799 	if (!nfserr)
2800 		nfsd4_encode_stateid(resp, &locku->lu_stateid);
2801 
2802 	encode_seqid_op_tail(resp, save, nfserr);
2803 	return nfserr;
2804 }
2805 
2806 
2807 static __be32
2808 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
2809 {
2810 	__be32 *p;
2811 
2812 	if (!nfserr) {
2813 		RESERVE_SPACE(20);
2814 		write_cinfo(&p, &link->li_cinfo);
2815 		ADJUST_ARGS();
2816 	}
2817 	return nfserr;
2818 }
2819 
2820 
2821 static __be32
2822 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
2823 {
2824 	__be32 *p;
2825 	ENCODE_SEQID_OP_HEAD;
2826 
2827 	if (nfserr)
2828 		goto out;
2829 
2830 	nfsd4_encode_stateid(resp, &open->op_stateid);
2831 	RESERVE_SPACE(40);
2832 	write_cinfo(&p, &open->op_cinfo);
2833 	WRITE32(open->op_rflags);
2834 	WRITE32(2);
2835 	WRITE32(open->op_bmval[0]);
2836 	WRITE32(open->op_bmval[1]);
2837 	WRITE32(open->op_delegate_type);
2838 	ADJUST_ARGS();
2839 
2840 	switch (open->op_delegate_type) {
2841 	case NFS4_OPEN_DELEGATE_NONE:
2842 		break;
2843 	case NFS4_OPEN_DELEGATE_READ:
2844 		nfsd4_encode_stateid(resp, &open->op_delegate_stateid);
2845 		RESERVE_SPACE(20);
2846 		WRITE32(open->op_recall);
2847 
2848 		/*
2849 		 * TODO: ACE's in delegations
2850 		 */
2851 		WRITE32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
2852 		WRITE32(0);
2853 		WRITE32(0);
2854 		WRITE32(0);   /* XXX: is NULL principal ok? */
2855 		ADJUST_ARGS();
2856 		break;
2857 	case NFS4_OPEN_DELEGATE_WRITE:
2858 		nfsd4_encode_stateid(resp, &open->op_delegate_stateid);
2859 		RESERVE_SPACE(32);
2860 		WRITE32(0);
2861 
2862 		/*
2863 		 * TODO: space_limit's in delegations
2864 		 */
2865 		WRITE32(NFS4_LIMIT_SIZE);
2866 		WRITE32(~(u32)0);
2867 		WRITE32(~(u32)0);
2868 
2869 		/*
2870 		 * TODO: ACE's in delegations
2871 		 */
2872 		WRITE32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
2873 		WRITE32(0);
2874 		WRITE32(0);
2875 		WRITE32(0);   /* XXX: is NULL principal ok? */
2876 		ADJUST_ARGS();
2877 		break;
2878 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
2879 		switch (open->op_why_no_deleg) {
2880 		case WND4_CONTENTION:
2881 		case WND4_RESOURCE:
2882 			RESERVE_SPACE(8);
2883 			WRITE32(open->op_why_no_deleg);
2884 			WRITE32(0);	/* deleg signaling not supported yet */
2885 			break;
2886 		default:
2887 			RESERVE_SPACE(4);
2888 			WRITE32(open->op_why_no_deleg);
2889 		}
2890 		ADJUST_ARGS();
2891 		break;
2892 	default:
2893 		BUG();
2894 	}
2895 	/* XXX save filehandle here */
2896 out:
2897 	encode_seqid_op_tail(resp, save, nfserr);
2898 	return nfserr;
2899 }
2900 
2901 static __be32
2902 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
2903 {
2904 	ENCODE_SEQID_OP_HEAD;
2905 
2906 	if (!nfserr)
2907 		nfsd4_encode_stateid(resp, &oc->oc_resp_stateid);
2908 
2909 	encode_seqid_op_tail(resp, save, nfserr);
2910 	return nfserr;
2911 }
2912 
2913 static __be32
2914 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
2915 {
2916 	ENCODE_SEQID_OP_HEAD;
2917 
2918 	if (!nfserr)
2919 		nfsd4_encode_stateid(resp, &od->od_stateid);
2920 
2921 	encode_seqid_op_tail(resp, save, nfserr);
2922 	return nfserr;
2923 }
2924 
2925 static __be32
2926 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
2927 		  struct nfsd4_read *read)
2928 {
2929 	u32 eof;
2930 	int v, pn;
2931 	unsigned long maxcount;
2932 	long len;
2933 	__be32 *p;
2934 
2935 	if (nfserr)
2936 		return nfserr;
2937 	if (resp->xbuf->page_len)
2938 		return nfserr_resource;
2939 
2940 	RESERVE_SPACE(8); /* eof flag and byte count */
2941 
2942 	maxcount = svc_max_payload(resp->rqstp);
2943 	if (maxcount > read->rd_length)
2944 		maxcount = read->rd_length;
2945 
2946 	len = maxcount;
2947 	v = 0;
2948 	while (len > 0) {
2949 		pn = resp->rqstp->rq_resused++;
2950 		resp->rqstp->rq_vec[v].iov_base =
2951 			page_address(resp->rqstp->rq_respages[pn]);
2952 		resp->rqstp->rq_vec[v].iov_len =
2953 			len < PAGE_SIZE ? len : PAGE_SIZE;
2954 		v++;
2955 		len -= PAGE_SIZE;
2956 	}
2957 	read->rd_vlen = v;
2958 
2959 	nfserr = nfsd_read_file(read->rd_rqstp, read->rd_fhp, read->rd_filp,
2960 			read->rd_offset, resp->rqstp->rq_vec, read->rd_vlen,
2961 			&maxcount);
2962 
2963 	if (nfserr)
2964 		return nfserr;
2965 	eof = (read->rd_offset + maxcount >=
2966 	       read->rd_fhp->fh_dentry->d_inode->i_size);
2967 
2968 	WRITE32(eof);
2969 	WRITE32(maxcount);
2970 	ADJUST_ARGS();
2971 	resp->xbuf->head[0].iov_len = (char*)p
2972 					- (char*)resp->xbuf->head[0].iov_base;
2973 	resp->xbuf->page_len = maxcount;
2974 
2975 	/* Use rest of head for padding and remaining ops: */
2976 	resp->xbuf->tail[0].iov_base = p;
2977 	resp->xbuf->tail[0].iov_len = 0;
2978 	if (maxcount&3) {
2979 		RESERVE_SPACE(4);
2980 		WRITE32(0);
2981 		resp->xbuf->tail[0].iov_base += maxcount&3;
2982 		resp->xbuf->tail[0].iov_len = 4 - (maxcount&3);
2983 		ADJUST_ARGS();
2984 	}
2985 	return 0;
2986 }
2987 
2988 static __be32
2989 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
2990 {
2991 	int maxcount;
2992 	char *page;
2993 	__be32 *p;
2994 
2995 	if (nfserr)
2996 		return nfserr;
2997 	if (resp->xbuf->page_len)
2998 		return nfserr_resource;
2999 
3000 	page = page_address(resp->rqstp->rq_respages[resp->rqstp->rq_resused++]);
3001 
3002 	maxcount = PAGE_SIZE;
3003 	RESERVE_SPACE(4);
3004 
3005 	/*
3006 	 * XXX: By default, the ->readlink() VFS op will truncate symlinks
3007 	 * if they would overflow the buffer.  Is this kosher in NFSv4?  If
3008 	 * not, one easy fix is: if ->readlink() precisely fills the buffer,
3009 	 * assume that truncation occurred, and return NFS4ERR_RESOURCE.
3010 	 */
3011 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp, page, &maxcount);
3012 	if (nfserr == nfserr_isdir)
3013 		return nfserr_inval;
3014 	if (nfserr)
3015 		return nfserr;
3016 
3017 	WRITE32(maxcount);
3018 	ADJUST_ARGS();
3019 	resp->xbuf->head[0].iov_len = (char*)p
3020 				- (char*)resp->xbuf->head[0].iov_base;
3021 	resp->xbuf->page_len = maxcount;
3022 
3023 	/* Use rest of head for padding and remaining ops: */
3024 	resp->xbuf->tail[0].iov_base = p;
3025 	resp->xbuf->tail[0].iov_len = 0;
3026 	if (maxcount&3) {
3027 		RESERVE_SPACE(4);
3028 		WRITE32(0);
3029 		resp->xbuf->tail[0].iov_base += maxcount&3;
3030 		resp->xbuf->tail[0].iov_len = 4 - (maxcount&3);
3031 		ADJUST_ARGS();
3032 	}
3033 	return 0;
3034 }
3035 
3036 static __be32
3037 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3038 {
3039 	int maxcount;
3040 	loff_t offset;
3041 	__be32 *page, *savep, *tailbase;
3042 	__be32 *p;
3043 
3044 	if (nfserr)
3045 		return nfserr;
3046 	if (resp->xbuf->page_len)
3047 		return nfserr_resource;
3048 
3049 	RESERVE_SPACE(NFS4_VERIFIER_SIZE);
3050 	savep = p;
3051 
3052 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3053 	WRITE32(0);
3054 	WRITE32(0);
3055 	ADJUST_ARGS();
3056 	resp->xbuf->head[0].iov_len = ((char*)resp->p) - (char*)resp->xbuf->head[0].iov_base;
3057 	tailbase = p;
3058 
3059 	maxcount = PAGE_SIZE;
3060 	if (maxcount > readdir->rd_maxcount)
3061 		maxcount = readdir->rd_maxcount;
3062 
3063 	/*
3064 	 * Convert from bytes to words, account for the two words already
3065 	 * written, make sure to leave two words at the end for the next
3066 	 * pointer and eof field.
3067 	 */
3068 	maxcount = (maxcount >> 2) - 4;
3069 	if (maxcount < 0) {
3070 		nfserr =  nfserr_toosmall;
3071 		goto err_no_verf;
3072 	}
3073 
3074 	page = page_address(resp->rqstp->rq_respages[resp->rqstp->rq_resused++]);
3075 	readdir->common.err = 0;
3076 	readdir->buflen = maxcount;
3077 	readdir->buffer = page;
3078 	readdir->offset = NULL;
3079 
3080 	offset = readdir->rd_cookie;
3081 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3082 			      &offset,
3083 			      &readdir->common, nfsd4_encode_dirent);
3084 	if (nfserr == nfs_ok &&
3085 	    readdir->common.err == nfserr_toosmall &&
3086 	    readdir->buffer == page)
3087 		nfserr = nfserr_toosmall;
3088 	if (nfserr)
3089 		goto err_no_verf;
3090 
3091 	if (readdir->offset)
3092 		xdr_encode_hyper(readdir->offset, offset);
3093 
3094 	p = readdir->buffer;
3095 	*p++ = 0;	/* no more entries */
3096 	*p++ = htonl(readdir->common.err == nfserr_eof);
3097 	resp->xbuf->page_len = ((char*)p) - (char*)page_address(
3098 		resp->rqstp->rq_respages[resp->rqstp->rq_resused-1]);
3099 
3100 	/* Use rest of head for padding and remaining ops: */
3101 	resp->xbuf->tail[0].iov_base = tailbase;
3102 	resp->xbuf->tail[0].iov_len = 0;
3103 	resp->p = resp->xbuf->tail[0].iov_base;
3104 	resp->end = resp->p + (PAGE_SIZE - resp->xbuf->head[0].iov_len)/4;
3105 
3106 	return 0;
3107 err_no_verf:
3108 	p = savep;
3109 	ADJUST_ARGS();
3110 	return nfserr;
3111 }
3112 
3113 static __be32
3114 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3115 {
3116 	__be32 *p;
3117 
3118 	if (!nfserr) {
3119 		RESERVE_SPACE(20);
3120 		write_cinfo(&p, &remove->rm_cinfo);
3121 		ADJUST_ARGS();
3122 	}
3123 	return nfserr;
3124 }
3125 
3126 static __be32
3127 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3128 {
3129 	__be32 *p;
3130 
3131 	if (!nfserr) {
3132 		RESERVE_SPACE(40);
3133 		write_cinfo(&p, &rename->rn_sinfo);
3134 		write_cinfo(&p, &rename->rn_tinfo);
3135 		ADJUST_ARGS();
3136 	}
3137 	return nfserr;
3138 }
3139 
3140 static __be32
3141 nfsd4_do_encode_secinfo(struct nfsd4_compoundres *resp,
3142 			 __be32 nfserr,struct svc_export *exp)
3143 {
3144 	int i = 0;
3145 	u32 nflavs;
3146 	struct exp_flavor_info *flavs;
3147 	struct exp_flavor_info def_flavs[2];
3148 	__be32 *p;
3149 
3150 	if (nfserr)
3151 		goto out;
3152 	if (exp->ex_nflavors) {
3153 		flavs = exp->ex_flavors;
3154 		nflavs = exp->ex_nflavors;
3155 	} else { /* Handling of some defaults in absence of real secinfo: */
3156 		flavs = def_flavs;
3157 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3158 			nflavs = 2;
3159 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3160 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3161 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3162 			nflavs = 1;
3163 			flavs[0].pseudoflavor
3164 					= svcauth_gss_flavor(exp->ex_client);
3165 		} else {
3166 			nflavs = 1;
3167 			flavs[0].pseudoflavor
3168 					= exp->ex_client->flavour->flavour;
3169 		}
3170 	}
3171 
3172 	RESERVE_SPACE(4);
3173 	WRITE32(nflavs);
3174 	ADJUST_ARGS();
3175 	for (i = 0; i < nflavs; i++) {
3176 		u32 flav = flavs[i].pseudoflavor;
3177 		struct gss_api_mech *gm = gss_mech_get_by_pseudoflavor(flav);
3178 
3179 		if (gm) {
3180 			RESERVE_SPACE(4);
3181 			WRITE32(RPC_AUTH_GSS);
3182 			ADJUST_ARGS();
3183 			RESERVE_SPACE(4 + gm->gm_oid.len);
3184 			WRITE32(gm->gm_oid.len);
3185 			WRITEMEM(gm->gm_oid.data, gm->gm_oid.len);
3186 			ADJUST_ARGS();
3187 			RESERVE_SPACE(4);
3188 			WRITE32(0); /* qop */
3189 			ADJUST_ARGS();
3190 			RESERVE_SPACE(4);
3191 			WRITE32(gss_pseudoflavor_to_service(gm, flav));
3192 			ADJUST_ARGS();
3193 			gss_mech_put(gm);
3194 		} else {
3195 			RESERVE_SPACE(4);
3196 			WRITE32(flav);
3197 			ADJUST_ARGS();
3198 		}
3199 	}
3200 out:
3201 	if (exp)
3202 		exp_put(exp);
3203 	return nfserr;
3204 }
3205 
3206 static __be32
3207 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3208 		     struct nfsd4_secinfo *secinfo)
3209 {
3210 	return nfsd4_do_encode_secinfo(resp, nfserr, secinfo->si_exp);
3211 }
3212 
3213 static __be32
3214 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3215 		     struct nfsd4_secinfo_no_name *secinfo)
3216 {
3217 	return nfsd4_do_encode_secinfo(resp, nfserr, secinfo->sin_exp);
3218 }
3219 
3220 /*
3221  * The SETATTR encode routine is special -- it always encodes a bitmap,
3222  * regardless of the error status.
3223  */
3224 static __be32
3225 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3226 {
3227 	__be32 *p;
3228 
3229 	RESERVE_SPACE(12);
3230 	if (nfserr) {
3231 		WRITE32(2);
3232 		WRITE32(0);
3233 		WRITE32(0);
3234 	}
3235 	else {
3236 		WRITE32(2);
3237 		WRITE32(setattr->sa_bmval[0]);
3238 		WRITE32(setattr->sa_bmval[1]);
3239 	}
3240 	ADJUST_ARGS();
3241 	return nfserr;
3242 }
3243 
3244 static __be32
3245 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3246 {
3247 	__be32 *p;
3248 
3249 	if (!nfserr) {
3250 		RESERVE_SPACE(8 + NFS4_VERIFIER_SIZE);
3251 		WRITEMEM(&scd->se_clientid, 8);
3252 		WRITEMEM(&scd->se_confirm, NFS4_VERIFIER_SIZE);
3253 		ADJUST_ARGS();
3254 	}
3255 	else if (nfserr == nfserr_clid_inuse) {
3256 		RESERVE_SPACE(8);
3257 		WRITE32(0);
3258 		WRITE32(0);
3259 		ADJUST_ARGS();
3260 	}
3261 	return nfserr;
3262 }
3263 
3264 static __be32
3265 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3266 {
3267 	__be32 *p;
3268 
3269 	if (!nfserr) {
3270 		RESERVE_SPACE(16);
3271 		WRITE32(write->wr_bytes_written);
3272 		WRITE32(write->wr_how_written);
3273 		WRITEMEM(write->wr_verifier.data, NFS4_VERIFIER_SIZE);
3274 		ADJUST_ARGS();
3275 	}
3276 	return nfserr;
3277 }
3278 
3279 static __be32
3280 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
3281 			 struct nfsd4_exchange_id *exid)
3282 {
3283 	__be32 *p;
3284 	char *major_id;
3285 	char *server_scope;
3286 	int major_id_sz;
3287 	int server_scope_sz;
3288 	uint64_t minor_id = 0;
3289 
3290 	if (nfserr)
3291 		return nfserr;
3292 
3293 	major_id = utsname()->nodename;
3294 	major_id_sz = strlen(major_id);
3295 	server_scope = utsname()->nodename;
3296 	server_scope_sz = strlen(server_scope);
3297 
3298 	RESERVE_SPACE(
3299 		8 /* eir_clientid */ +
3300 		4 /* eir_sequenceid */ +
3301 		4 /* eir_flags */ +
3302 		4 /* spr_how (SP4_NONE) */ +
3303 		8 /* so_minor_id */ +
3304 		4 /* so_major_id.len */ +
3305 		(XDR_QUADLEN(major_id_sz) * 4) +
3306 		4 /* eir_server_scope.len */ +
3307 		(XDR_QUADLEN(server_scope_sz) * 4) +
3308 		4 /* eir_server_impl_id.count (0) */);
3309 
3310 	WRITEMEM(&exid->clientid, 8);
3311 	WRITE32(exid->seqid);
3312 	WRITE32(exid->flags);
3313 
3314 	/* state_protect4_r. Currently only support SP4_NONE */
3315 	BUG_ON(exid->spa_how != SP4_NONE);
3316 	WRITE32(exid->spa_how);
3317 
3318 	/* The server_owner struct */
3319 	WRITE64(minor_id);      /* Minor id */
3320 	/* major id */
3321 	WRITE32(major_id_sz);
3322 	WRITEMEM(major_id, major_id_sz);
3323 
3324 	/* Server scope */
3325 	WRITE32(server_scope_sz);
3326 	WRITEMEM(server_scope, server_scope_sz);
3327 
3328 	/* Implementation id */
3329 	WRITE32(0);	/* zero length nfs_impl_id4 array */
3330 	ADJUST_ARGS();
3331 	return 0;
3332 }
3333 
3334 static __be32
3335 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
3336 			    struct nfsd4_create_session *sess)
3337 {
3338 	__be32 *p;
3339 
3340 	if (nfserr)
3341 		return nfserr;
3342 
3343 	RESERVE_SPACE(24);
3344 	WRITEMEM(sess->sessionid.data, NFS4_MAX_SESSIONID_LEN);
3345 	WRITE32(sess->seqid);
3346 	WRITE32(sess->flags);
3347 	ADJUST_ARGS();
3348 
3349 	RESERVE_SPACE(28);
3350 	WRITE32(0); /* headerpadsz */
3351 	WRITE32(sess->fore_channel.maxreq_sz);
3352 	WRITE32(sess->fore_channel.maxresp_sz);
3353 	WRITE32(sess->fore_channel.maxresp_cached);
3354 	WRITE32(sess->fore_channel.maxops);
3355 	WRITE32(sess->fore_channel.maxreqs);
3356 	WRITE32(sess->fore_channel.nr_rdma_attrs);
3357 	ADJUST_ARGS();
3358 
3359 	if (sess->fore_channel.nr_rdma_attrs) {
3360 		RESERVE_SPACE(4);
3361 		WRITE32(sess->fore_channel.rdma_attrs);
3362 		ADJUST_ARGS();
3363 	}
3364 
3365 	RESERVE_SPACE(28);
3366 	WRITE32(0); /* headerpadsz */
3367 	WRITE32(sess->back_channel.maxreq_sz);
3368 	WRITE32(sess->back_channel.maxresp_sz);
3369 	WRITE32(sess->back_channel.maxresp_cached);
3370 	WRITE32(sess->back_channel.maxops);
3371 	WRITE32(sess->back_channel.maxreqs);
3372 	WRITE32(sess->back_channel.nr_rdma_attrs);
3373 	ADJUST_ARGS();
3374 
3375 	if (sess->back_channel.nr_rdma_attrs) {
3376 		RESERVE_SPACE(4);
3377 		WRITE32(sess->back_channel.rdma_attrs);
3378 		ADJUST_ARGS();
3379 	}
3380 	return 0;
3381 }
3382 
3383 static __be32
3384 nfsd4_encode_destroy_session(struct nfsd4_compoundres *resp, __be32 nfserr,
3385 			     struct nfsd4_destroy_session *destroy_session)
3386 {
3387 	return nfserr;
3388 }
3389 
3390 static __be32
3391 nfsd4_encode_free_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
3392 			  struct nfsd4_free_stateid *free_stateid)
3393 {
3394 	__be32 *p;
3395 
3396 	if (nfserr)
3397 		return nfserr;
3398 
3399 	RESERVE_SPACE(4);
3400 	*p++ = nfserr;
3401 	ADJUST_ARGS();
3402 	return nfserr;
3403 }
3404 
3405 static __be32
3406 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
3407 		      struct nfsd4_sequence *seq)
3408 {
3409 	__be32 *p;
3410 
3411 	if (nfserr)
3412 		return nfserr;
3413 
3414 	RESERVE_SPACE(NFS4_MAX_SESSIONID_LEN + 20);
3415 	WRITEMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
3416 	WRITE32(seq->seqid);
3417 	WRITE32(seq->slotid);
3418 	/* Note slotid's are numbered from zero: */
3419 	WRITE32(seq->maxslots - 1); /* sr_highest_slotid */
3420 	WRITE32(seq->maxslots - 1); /* sr_target_highest_slotid */
3421 	WRITE32(seq->status_flags);
3422 
3423 	ADJUST_ARGS();
3424 	resp->cstate.datap = p; /* DRC cache data pointer */
3425 	return 0;
3426 }
3427 
3428 static __be32
3429 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
3430 			  struct nfsd4_test_stateid *test_stateid)
3431 {
3432 	struct nfsd4_test_stateid_id *stateid, *next;
3433 	__be32 *p;
3434 
3435 	RESERVE_SPACE(4 + (4 * test_stateid->ts_num_ids));
3436 	*p++ = htonl(test_stateid->ts_num_ids);
3437 
3438 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
3439 		*p++ = stateid->ts_id_status;
3440 	}
3441 
3442 	ADJUST_ARGS();
3443 	return nfserr;
3444 }
3445 
3446 static __be32
3447 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
3448 {
3449 	return nfserr;
3450 }
3451 
3452 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
3453 
3454 /*
3455  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
3456  * since we don't need to filter out obsolete ops as this is
3457  * done in the decoding phase.
3458  */
3459 static nfsd4_enc nfsd4_enc_ops[] = {
3460 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
3461 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
3462 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
3463 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
3464 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
3465 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
3466 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
3467 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
3468 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
3469 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
3470 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
3471 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
3472 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
3473 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
3474 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
3475 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
3476 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
3477 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
3478 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
3479 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
3480 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
3481 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
3482 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
3483 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
3484 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
3485 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
3486 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
3487 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
3488 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
3489 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
3490 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
3491 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
3492 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
3493 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
3494 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
3495 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
3496 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
3497 
3498 	/* NFSv4.1 operations */
3499 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
3500 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
3501 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
3502 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
3503 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_destroy_session,
3504 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_free_stateid,
3505 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
3506 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
3507 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
3508 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
3509 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
3510 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
3511 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
3512 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
3513 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
3514 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
3515 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
3516 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
3517 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
3518 };
3519 
3520 /*
3521  * Calculate the total amount of memory that the compound response has taken
3522  * after encoding the current operation with pad.
3523  *
3524  * pad: if operation is non-idempotent, pad was calculate by op_rsize_bop()
3525  *      which was specified at nfsd4_operation, else pad is zero.
3526  *
3527  * Compare this length to the session se_fmaxresp_sz and se_fmaxresp_cached.
3528  *
3529  * Our se_fmaxresp_cached will always be a multiple of PAGE_SIZE, and so
3530  * will be at least a page and will therefore hold the xdr_buf head.
3531  */
3532 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 pad)
3533 {
3534 	struct xdr_buf *xb = &resp->rqstp->rq_res;
3535 	struct nfsd4_session *session = NULL;
3536 	struct nfsd4_slot *slot = resp->cstate.slot;
3537 	u32 length, tlen = 0;
3538 
3539 	if (!nfsd4_has_session(&resp->cstate))
3540 		return 0;
3541 
3542 	session = resp->cstate.session;
3543 	if (session == NULL)
3544 		return 0;
3545 
3546 	if (xb->page_len == 0) {
3547 		length = (char *)resp->p - (char *)xb->head[0].iov_base + pad;
3548 	} else {
3549 		if (xb->tail[0].iov_base && xb->tail[0].iov_len > 0)
3550 			tlen = (char *)resp->p - (char *)xb->tail[0].iov_base;
3551 
3552 		length = xb->head[0].iov_len + xb->page_len + tlen + pad;
3553 	}
3554 	dprintk("%s length %u, xb->page_len %u tlen %u pad %u\n", __func__,
3555 		length, xb->page_len, tlen, pad);
3556 
3557 	if (length > session->se_fchannel.maxresp_sz)
3558 		return nfserr_rep_too_big;
3559 
3560 	if ((slot->sl_flags & NFSD4_SLOT_CACHETHIS) &&
3561 	    length > session->se_fchannel.maxresp_cached)
3562 		return nfserr_rep_too_big_to_cache;
3563 
3564 	return 0;
3565 }
3566 
3567 void
3568 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
3569 {
3570 	__be32 *statp;
3571 	__be32 *p;
3572 
3573 	RESERVE_SPACE(8);
3574 	WRITE32(op->opnum);
3575 	statp = p++;	/* to be backfilled at the end */
3576 	ADJUST_ARGS();
3577 
3578 	if (op->opnum == OP_ILLEGAL)
3579 		goto status;
3580 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
3581 	       !nfsd4_enc_ops[op->opnum]);
3582 	op->status = nfsd4_enc_ops[op->opnum](resp, op->status, &op->u);
3583 	/* nfsd4_check_drc_limit guarantees enough room for error status */
3584 	if (!op->status)
3585 		op->status = nfsd4_check_resp_size(resp, 0);
3586 status:
3587 	/*
3588 	 * Note: We write the status directly, instead of using WRITE32(),
3589 	 * since it is already in network byte order.
3590 	 */
3591 	*statp = op->status;
3592 }
3593 
3594 /*
3595  * Encode the reply stored in the stateowner reply cache
3596  *
3597  * XDR note: do not encode rp->rp_buflen: the buffer contains the
3598  * previously sent already encoded operation.
3599  *
3600  * called with nfs4_lock_state() held
3601  */
3602 void
3603 nfsd4_encode_replay(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
3604 {
3605 	__be32 *p;
3606 	struct nfs4_replay *rp = op->replay;
3607 
3608 	BUG_ON(!rp);
3609 
3610 	RESERVE_SPACE(8);
3611 	WRITE32(op->opnum);
3612 	*p++ = rp->rp_status;  /* already xdr'ed */
3613 	ADJUST_ARGS();
3614 
3615 	RESERVE_SPACE(rp->rp_buflen);
3616 	WRITEMEM(rp->rp_buf, rp->rp_buflen);
3617 	ADJUST_ARGS();
3618 }
3619 
3620 int
3621 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
3622 {
3623         return xdr_ressize_check(rqstp, p);
3624 }
3625 
3626 int nfsd4_release_compoundargs(void *rq, __be32 *p, void *resp)
3627 {
3628 	struct svc_rqst *rqstp = rq;
3629 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
3630 
3631 	if (args->ops != args->iops) {
3632 		kfree(args->ops);
3633 		args->ops = args->iops;
3634 	}
3635 	kfree(args->tmpp);
3636 	args->tmpp = NULL;
3637 	while (args->to_free) {
3638 		struct tmpbuf *tb = args->to_free;
3639 		args->to_free = tb->next;
3640 		tb->release(tb->buf);
3641 		kfree(tb);
3642 	}
3643 	return 1;
3644 }
3645 
3646 int
3647 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundargs *args)
3648 {
3649 	args->p = p;
3650 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
3651 	args->pagelist = rqstp->rq_arg.pages;
3652 	args->pagelen = rqstp->rq_arg.page_len;
3653 	args->tmpp = NULL;
3654 	args->to_free = NULL;
3655 	args->ops = args->iops;
3656 	args->rqstp = rqstp;
3657 
3658 	return !nfsd4_decode_compound(args);
3659 }
3660 
3661 int
3662 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundres *resp)
3663 {
3664 	/*
3665 	 * All that remains is to write the tag and operation count...
3666 	 */
3667 	struct nfsd4_compound_state *cs = &resp->cstate;
3668 	struct kvec *iov;
3669 	p = resp->tagp;
3670 	*p++ = htonl(resp->taglen);
3671 	memcpy(p, resp->tag, resp->taglen);
3672 	p += XDR_QUADLEN(resp->taglen);
3673 	*p++ = htonl(resp->opcnt);
3674 
3675 	if (rqstp->rq_res.page_len)
3676 		iov = &rqstp->rq_res.tail[0];
3677 	else
3678 		iov = &rqstp->rq_res.head[0];
3679 	iov->iov_len = ((char*)resp->p) - (char*)iov->iov_base;
3680 	BUG_ON(iov->iov_len > PAGE_SIZE);
3681 	if (nfsd4_has_session(cs)) {
3682 		if (cs->status != nfserr_replay_cache) {
3683 			nfsd4_store_cache_entry(resp);
3684 			cs->slot->sl_flags &= ~NFSD4_SLOT_INUSE;
3685 		}
3686 		/* Renew the clientid on success and on replay */
3687 		release_session_client(cs->session);
3688 		nfsd4_put_session(cs->session);
3689 	}
3690 	return 1;
3691 }
3692 
3693 /*
3694  * Local variables:
3695  *  c-basic-offset: 8
3696  * End:
3697  */
3698