xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision 4cd968ef)
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 
36 #include <linux/slab.h>
37 #include <linux/namei.h>
38 #include <linux/statfs.h>
39 #include <linux/utsname.h>
40 #include <linux/pagemap.h>
41 #include <linux/sunrpc/svcauth_gss.h>
42 
43 #include "idmap.h"
44 #include "acl.h"
45 #include "xdr4.h"
46 #include "vfs.h"
47 #include "state.h"
48 #include "cache.h"
49 #include "netns.h"
50 #include "pnfs.h"
51 
52 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
53 #include <linux/security.h>
54 #endif
55 
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)
69 {
70 	int i;
71 
72 	if (len == 0)
73 		return nfserr_inval;
74 	if (isdotent(str, len))
75 		return nfserr_badname;
76 	for (i = 0; i < len; i++)
77 		if (str[i] == '/')
78 			return nfserr_badname;
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 READMEM(x,nbytes) do {			\
96 	x = (char *)p;				\
97 	p += XDR_QUADLEN(nbytes);		\
98 } while (0)
99 #define SAVEMEM(x,nbytes) do {			\
100 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
101  		savemem(argp, p, nbytes) :	\
102  		(char *)p)) {			\
103 		dprintk("NFSD: xdr error (%s:%d)\n", \
104 				__FILE__, __LINE__); \
105 		goto xdr_error;			\
106 		}				\
107 	p += XDR_QUADLEN(nbytes);		\
108 } while (0)
109 #define COPYMEM(x,nbytes) do {			\
110 	memcpy((x), p, nbytes);			\
111 	p += XDR_QUADLEN(nbytes);		\
112 } while (0)
113 
114 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
115 #define READ_BUF(nbytes)  do {			\
116 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
117 		p = argp->p;			\
118 		argp->p += XDR_QUADLEN(nbytes);	\
119 	} else if (!(p = read_buf(argp, nbytes))) { \
120 		dprintk("NFSD: xdr error (%s:%d)\n", \
121 				__FILE__, __LINE__); \
122 		goto xdr_error;			\
123 	}					\
124 } while (0)
125 
126 static void next_decode_page(struct nfsd4_compoundargs *argp)
127 {
128 	argp->p = page_address(argp->pagelist[0]);
129 	argp->pagelist++;
130 	if (argp->pagelen < PAGE_SIZE) {
131 		argp->end = argp->p + (argp->pagelen>>2);
132 		argp->pagelen = 0;
133 	} else {
134 		argp->end = argp->p + (PAGE_SIZE>>2);
135 		argp->pagelen -= PAGE_SIZE;
136 	}
137 }
138 
139 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
140 {
141 	/* We want more bytes than seem to be available.
142 	 * Maybe we need a new page, maybe we have just run out
143 	 */
144 	unsigned int avail = (char *)argp->end - (char *)argp->p;
145 	__be32 *p;
146 	if (avail + argp->pagelen < nbytes)
147 		return NULL;
148 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
149 		return NULL;
150 	/* ok, we can do it with the current plus the next page */
151 	if (nbytes <= sizeof(argp->tmp))
152 		p = argp->tmp;
153 	else {
154 		kfree(argp->tmpp);
155 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
156 		if (!p)
157 			return NULL;
158 
159 	}
160 	/*
161 	 * The following memcpy is safe because read_buf is always
162 	 * called with nbytes > avail, and the two cases above both
163 	 * guarantee p points to at least nbytes bytes.
164 	 */
165 	memcpy(p, argp->p, avail);
166 	next_decode_page(argp);
167 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
168 	argp->p += XDR_QUADLEN(nbytes - avail);
169 	return p;
170 }
171 
172 static int zero_clientid(clientid_t *clid)
173 {
174 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
175 }
176 
177 /**
178  * svcxdr_tmpalloc - allocate memory to be freed after compound processing
179  * @argp: NFSv4 compound argument structure
180  * @p: pointer to be freed (with kfree())
181  *
182  * Marks @p to be freed when processing the compound operation
183  * described in @argp finishes.
184  */
185 static void *
186 svcxdr_tmpalloc(struct nfsd4_compoundargs *argp, u32 len)
187 {
188 	struct svcxdr_tmpbuf *tb;
189 
190 	tb = kmalloc(sizeof(*tb) + len, GFP_KERNEL);
191 	if (!tb)
192 		return NULL;
193 	tb->next = argp->to_free;
194 	argp->to_free = tb;
195 	return tb->buf;
196 }
197 
198 /*
199  * For xdr strings that need to be passed to other kernel api's
200  * as null-terminated strings.
201  *
202  * Note null-terminating in place usually isn't safe since the
203  * buffer might end on a page boundary.
204  */
205 static char *
206 svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len)
207 {
208 	char *p = svcxdr_tmpalloc(argp, len + 1);
209 
210 	if (!p)
211 		return NULL;
212 	memcpy(p, buf, len);
213 	p[len] = '\0';
214 	return p;
215 }
216 
217 /**
218  * savemem - duplicate a chunk of memory for later processing
219  * @argp: NFSv4 compound argument structure to be freed with
220  * @p: pointer to be duplicated
221  * @nbytes: length to be duplicated
222  *
223  * Returns a pointer to a copy of @nbytes bytes of memory at @p
224  * that are preserved until processing of the NFSv4 compound
225  * operation described by @argp finishes.
226  */
227 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
228 {
229 	void *ret;
230 
231 	ret = svcxdr_tmpalloc(argp, nbytes);
232 	if (!ret)
233 		return NULL;
234 	memcpy(ret, p, nbytes);
235 	return ret;
236 }
237 
238 /*
239  * We require the high 32 bits of 'seconds' to be 0, and
240  * we ignore all 32 bits of 'nseconds'.
241  */
242 static __be32
243 nfsd4_decode_time(struct nfsd4_compoundargs *argp, struct timespec *tv)
244 {
245 	DECODE_HEAD;
246 	u64 sec;
247 
248 	READ_BUF(12);
249 	p = xdr_decode_hyper(p, &sec);
250 	tv->tv_sec = sec;
251 	tv->tv_nsec = be32_to_cpup(p++);
252 	if (tv->tv_nsec >= (u32)1000000000)
253 		return nfserr_inval;
254 
255 	DECODE_TAIL;
256 }
257 
258 static __be32
259 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
260 {
261 	u32 bmlen;
262 	DECODE_HEAD;
263 
264 	bmval[0] = 0;
265 	bmval[1] = 0;
266 	bmval[2] = 0;
267 
268 	READ_BUF(4);
269 	bmlen = be32_to_cpup(p++);
270 	if (bmlen > 1000)
271 		goto xdr_error;
272 
273 	READ_BUF(bmlen << 2);
274 	if (bmlen > 0)
275 		bmval[0] = be32_to_cpup(p++);
276 	if (bmlen > 1)
277 		bmval[1] = be32_to_cpup(p++);
278 	if (bmlen > 2)
279 		bmval[2] = be32_to_cpup(p++);
280 
281 	DECODE_TAIL;
282 }
283 
284 static __be32
285 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
286 		   struct iattr *iattr, struct nfs4_acl **acl,
287 		   struct xdr_netobj *label)
288 {
289 	int expected_len, len = 0;
290 	u32 dummy32;
291 	char *buf;
292 
293 	DECODE_HEAD;
294 	iattr->ia_valid = 0;
295 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
296 		return status;
297 
298 	READ_BUF(4);
299 	expected_len = be32_to_cpup(p++);
300 
301 	if (bmval[0] & FATTR4_WORD0_SIZE) {
302 		READ_BUF(8);
303 		len += 8;
304 		p = xdr_decode_hyper(p, &iattr->ia_size);
305 		iattr->ia_valid |= ATTR_SIZE;
306 	}
307 	if (bmval[0] & FATTR4_WORD0_ACL) {
308 		u32 nace;
309 		struct nfs4_ace *ace;
310 
311 		READ_BUF(4); len += 4;
312 		nace = be32_to_cpup(p++);
313 
314 		if (nace > NFS4_ACL_MAX)
315 			return nfserr_fbig;
316 
317 		*acl = svcxdr_tmpalloc(argp, nfs4_acl_bytes(nace));
318 		if (*acl == NULL)
319 			return nfserr_jukebox;
320 
321 		(*acl)->naces = nace;
322 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
323 			READ_BUF(16); len += 16;
324 			ace->type = be32_to_cpup(p++);
325 			ace->flag = be32_to_cpup(p++);
326 			ace->access_mask = be32_to_cpup(p++);
327 			dummy32 = be32_to_cpup(p++);
328 			READ_BUF(dummy32);
329 			len += XDR_QUADLEN(dummy32) << 2;
330 			READMEM(buf, dummy32);
331 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
332 			status = nfs_ok;
333 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
334 				;
335 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
336 				status = nfsd_map_name_to_gid(argp->rqstp,
337 						buf, dummy32, &ace->who_gid);
338 			else
339 				status = nfsd_map_name_to_uid(argp->rqstp,
340 						buf, dummy32, &ace->who_uid);
341 			if (status)
342 				return status;
343 		}
344 	} else
345 		*acl = NULL;
346 	if (bmval[1] & FATTR4_WORD1_MODE) {
347 		READ_BUF(4);
348 		len += 4;
349 		iattr->ia_mode = be32_to_cpup(p++);
350 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
351 		iattr->ia_valid |= ATTR_MODE;
352 	}
353 	if (bmval[1] & FATTR4_WORD1_OWNER) {
354 		READ_BUF(4);
355 		len += 4;
356 		dummy32 = be32_to_cpup(p++);
357 		READ_BUF(dummy32);
358 		len += (XDR_QUADLEN(dummy32) << 2);
359 		READMEM(buf, dummy32);
360 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
361 			return status;
362 		iattr->ia_valid |= ATTR_UID;
363 	}
364 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
365 		READ_BUF(4);
366 		len += 4;
367 		dummy32 = be32_to_cpup(p++);
368 		READ_BUF(dummy32);
369 		len += (XDR_QUADLEN(dummy32) << 2);
370 		READMEM(buf, dummy32);
371 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
372 			return status;
373 		iattr->ia_valid |= ATTR_GID;
374 	}
375 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
376 		READ_BUF(4);
377 		len += 4;
378 		dummy32 = be32_to_cpup(p++);
379 		switch (dummy32) {
380 		case NFS4_SET_TO_CLIENT_TIME:
381 			len += 12;
382 			status = nfsd4_decode_time(argp, &iattr->ia_atime);
383 			if (status)
384 				return status;
385 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
386 			break;
387 		case NFS4_SET_TO_SERVER_TIME:
388 			iattr->ia_valid |= ATTR_ATIME;
389 			break;
390 		default:
391 			goto xdr_error;
392 		}
393 	}
394 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
395 		READ_BUF(4);
396 		len += 4;
397 		dummy32 = be32_to_cpup(p++);
398 		switch (dummy32) {
399 		case NFS4_SET_TO_CLIENT_TIME:
400 			len += 12;
401 			status = nfsd4_decode_time(argp, &iattr->ia_mtime);
402 			if (status)
403 				return status;
404 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
405 			break;
406 		case NFS4_SET_TO_SERVER_TIME:
407 			iattr->ia_valid |= ATTR_MTIME;
408 			break;
409 		default:
410 			goto xdr_error;
411 		}
412 	}
413 
414 	label->len = 0;
415 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
416 	if (bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
417 		READ_BUF(4);
418 		len += 4;
419 		dummy32 = be32_to_cpup(p++); /* lfs: we don't use it */
420 		READ_BUF(4);
421 		len += 4;
422 		dummy32 = be32_to_cpup(p++); /* pi: we don't use it either */
423 		READ_BUF(4);
424 		len += 4;
425 		dummy32 = be32_to_cpup(p++);
426 		READ_BUF(dummy32);
427 		if (dummy32 > NFSD4_MAX_SEC_LABEL_LEN)
428 			return nfserr_badlabel;
429 		len += (XDR_QUADLEN(dummy32) << 2);
430 		READMEM(buf, dummy32);
431 		label->len = dummy32;
432 		label->data = svcxdr_dupstr(argp, buf, dummy32);
433 		if (!label->data)
434 			return nfserr_jukebox;
435 	}
436 #endif
437 
438 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
439 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
440 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2)
441 		READ_BUF(expected_len - len);
442 	else if (len != expected_len)
443 		goto xdr_error;
444 
445 	DECODE_TAIL;
446 }
447 
448 static __be32
449 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
450 {
451 	DECODE_HEAD;
452 
453 	READ_BUF(sizeof(stateid_t));
454 	sid->si_generation = be32_to_cpup(p++);
455 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
456 
457 	DECODE_TAIL;
458 }
459 
460 static __be32
461 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
462 {
463 	DECODE_HEAD;
464 
465 	READ_BUF(4);
466 	access->ac_req_access = be32_to_cpup(p++);
467 
468 	DECODE_TAIL;
469 }
470 
471 static __be32 nfsd4_decode_cb_sec(struct nfsd4_compoundargs *argp, struct nfsd4_cb_sec *cbs)
472 {
473 	DECODE_HEAD;
474 	u32 dummy, uid, gid;
475 	char *machine_name;
476 	int i;
477 	int nr_secflavs;
478 
479 	/* callback_sec_params4 */
480 	READ_BUF(4);
481 	nr_secflavs = be32_to_cpup(p++);
482 	if (nr_secflavs)
483 		cbs->flavor = (u32)(-1);
484 	else
485 		/* Is this legal? Be generous, take it to mean AUTH_NONE: */
486 		cbs->flavor = 0;
487 	for (i = 0; i < nr_secflavs; ++i) {
488 		READ_BUF(4);
489 		dummy = be32_to_cpup(p++);
490 		switch (dummy) {
491 		case RPC_AUTH_NULL:
492 			/* Nothing to read */
493 			if (cbs->flavor == (u32)(-1))
494 				cbs->flavor = RPC_AUTH_NULL;
495 			break;
496 		case RPC_AUTH_UNIX:
497 			READ_BUF(8);
498 			/* stamp */
499 			dummy = be32_to_cpup(p++);
500 
501 			/* machine name */
502 			dummy = be32_to_cpup(p++);
503 			READ_BUF(dummy);
504 			SAVEMEM(machine_name, dummy);
505 
506 			/* uid, gid */
507 			READ_BUF(8);
508 			uid = be32_to_cpup(p++);
509 			gid = be32_to_cpup(p++);
510 
511 			/* more gids */
512 			READ_BUF(4);
513 			dummy = be32_to_cpup(p++);
514 			READ_BUF(dummy * 4);
515 			if (cbs->flavor == (u32)(-1)) {
516 				kuid_t kuid = make_kuid(&init_user_ns, uid);
517 				kgid_t kgid = make_kgid(&init_user_ns, gid);
518 				if (uid_valid(kuid) && gid_valid(kgid)) {
519 					cbs->uid = kuid;
520 					cbs->gid = kgid;
521 					cbs->flavor = RPC_AUTH_UNIX;
522 				} else {
523 					dprintk("RPC_AUTH_UNIX with invalid"
524 						"uid or gid ignoring!\n");
525 				}
526 			}
527 			break;
528 		case RPC_AUTH_GSS:
529 			dprintk("RPC_AUTH_GSS callback secflavor "
530 				"not supported!\n");
531 			READ_BUF(8);
532 			/* gcbp_service */
533 			dummy = be32_to_cpup(p++);
534 			/* gcbp_handle_from_server */
535 			dummy = be32_to_cpup(p++);
536 			READ_BUF(dummy);
537 			p += XDR_QUADLEN(dummy);
538 			/* gcbp_handle_from_client */
539 			READ_BUF(4);
540 			dummy = be32_to_cpup(p++);
541 			READ_BUF(dummy);
542 			break;
543 		default:
544 			dprintk("Illegal callback secflavor\n");
545 			return nfserr_inval;
546 		}
547 	}
548 	DECODE_TAIL;
549 }
550 
551 static __be32 nfsd4_decode_backchannel_ctl(struct nfsd4_compoundargs *argp, struct nfsd4_backchannel_ctl *bc)
552 {
553 	DECODE_HEAD;
554 
555 	READ_BUF(4);
556 	bc->bc_cb_program = be32_to_cpup(p++);
557 	nfsd4_decode_cb_sec(argp, &bc->bc_cb_sec);
558 
559 	DECODE_TAIL;
560 }
561 
562 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
563 {
564 	DECODE_HEAD;
565 
566 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
567 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
568 	bcts->dir = be32_to_cpup(p++);
569 	/* XXX: skipping ctsa_use_conn_in_rdma_mode.  Perhaps Tom Tucker
570 	 * could help us figure out we should be using it. */
571 	DECODE_TAIL;
572 }
573 
574 static __be32
575 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
576 {
577 	DECODE_HEAD;
578 
579 	READ_BUF(4);
580 	close->cl_seqid = be32_to_cpup(p++);
581 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
582 
583 	DECODE_TAIL;
584 }
585 
586 
587 static __be32
588 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
589 {
590 	DECODE_HEAD;
591 
592 	READ_BUF(12);
593 	p = xdr_decode_hyper(p, &commit->co_offset);
594 	commit->co_count = be32_to_cpup(p++);
595 
596 	DECODE_TAIL;
597 }
598 
599 static __be32
600 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
601 {
602 	DECODE_HEAD;
603 
604 	READ_BUF(4);
605 	create->cr_type = be32_to_cpup(p++);
606 	switch (create->cr_type) {
607 	case NF4LNK:
608 		READ_BUF(4);
609 		create->cr_datalen = be32_to_cpup(p++);
610 		READ_BUF(create->cr_datalen);
611 		create->cr_data = svcxdr_dupstr(argp, p, create->cr_datalen);
612 		if (!create->cr_data)
613 			return nfserr_jukebox;
614 		break;
615 	case NF4BLK:
616 	case NF4CHR:
617 		READ_BUF(8);
618 		create->cr_specdata1 = be32_to_cpup(p++);
619 		create->cr_specdata2 = be32_to_cpup(p++);
620 		break;
621 	case NF4SOCK:
622 	case NF4FIFO:
623 	case NF4DIR:
624 	default:
625 		break;
626 	}
627 
628 	READ_BUF(4);
629 	create->cr_namelen = be32_to_cpup(p++);
630 	READ_BUF(create->cr_namelen);
631 	SAVEMEM(create->cr_name, create->cr_namelen);
632 	if ((status = check_filename(create->cr_name, create->cr_namelen)))
633 		return status;
634 
635 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
636 				    &create->cr_acl, &create->cr_label);
637 	if (status)
638 		goto out;
639 
640 	DECODE_TAIL;
641 }
642 
643 static inline __be32
644 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
645 {
646 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
647 }
648 
649 static inline __be32
650 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
651 {
652 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
653 }
654 
655 static __be32
656 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
657 {
658 	DECODE_HEAD;
659 
660 	READ_BUF(4);
661 	link->li_namelen = be32_to_cpup(p++);
662 	READ_BUF(link->li_namelen);
663 	SAVEMEM(link->li_name, link->li_namelen);
664 	if ((status = check_filename(link->li_name, link->li_namelen)))
665 		return status;
666 
667 	DECODE_TAIL;
668 }
669 
670 static __be32
671 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
672 {
673 	DECODE_HEAD;
674 
675 	/*
676 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
677 	*/
678 	READ_BUF(28);
679 	lock->lk_type = be32_to_cpup(p++);
680 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
681 		goto xdr_error;
682 	lock->lk_reclaim = be32_to_cpup(p++);
683 	p = xdr_decode_hyper(p, &lock->lk_offset);
684 	p = xdr_decode_hyper(p, &lock->lk_length);
685 	lock->lk_is_new = be32_to_cpup(p++);
686 
687 	if (lock->lk_is_new) {
688 		READ_BUF(4);
689 		lock->lk_new_open_seqid = be32_to_cpup(p++);
690 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
691 		if (status)
692 			return status;
693 		READ_BUF(8 + sizeof(clientid_t));
694 		lock->lk_new_lock_seqid = be32_to_cpup(p++);
695 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
696 		lock->lk_new_owner.len = be32_to_cpup(p++);
697 		READ_BUF(lock->lk_new_owner.len);
698 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
699 	} else {
700 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
701 		if (status)
702 			return status;
703 		READ_BUF(4);
704 		lock->lk_old_lock_seqid = be32_to_cpup(p++);
705 	}
706 
707 	DECODE_TAIL;
708 }
709 
710 static __be32
711 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
712 {
713 	DECODE_HEAD;
714 
715 	READ_BUF(32);
716 	lockt->lt_type = be32_to_cpup(p++);
717 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
718 		goto xdr_error;
719 	p = xdr_decode_hyper(p, &lockt->lt_offset);
720 	p = xdr_decode_hyper(p, &lockt->lt_length);
721 	COPYMEM(&lockt->lt_clientid, 8);
722 	lockt->lt_owner.len = be32_to_cpup(p++);
723 	READ_BUF(lockt->lt_owner.len);
724 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
725 
726 	DECODE_TAIL;
727 }
728 
729 static __be32
730 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
731 {
732 	DECODE_HEAD;
733 
734 	READ_BUF(8);
735 	locku->lu_type = be32_to_cpup(p++);
736 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
737 		goto xdr_error;
738 	locku->lu_seqid = be32_to_cpup(p++);
739 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
740 	if (status)
741 		return status;
742 	READ_BUF(16);
743 	p = xdr_decode_hyper(p, &locku->lu_offset);
744 	p = xdr_decode_hyper(p, &locku->lu_length);
745 
746 	DECODE_TAIL;
747 }
748 
749 static __be32
750 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
751 {
752 	DECODE_HEAD;
753 
754 	READ_BUF(4);
755 	lookup->lo_len = be32_to_cpup(p++);
756 	READ_BUF(lookup->lo_len);
757 	SAVEMEM(lookup->lo_name, lookup->lo_len);
758 	if ((status = check_filename(lookup->lo_name, lookup->lo_len)))
759 		return status;
760 
761 	DECODE_TAIL;
762 }
763 
764 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
765 {
766 	__be32 *p;
767 	u32 w;
768 
769 	READ_BUF(4);
770 	w = be32_to_cpup(p++);
771 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
772 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
773 	if (deleg_when)
774 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
775 
776 	switch (w & NFS4_SHARE_ACCESS_MASK) {
777 	case NFS4_SHARE_ACCESS_READ:
778 	case NFS4_SHARE_ACCESS_WRITE:
779 	case NFS4_SHARE_ACCESS_BOTH:
780 		break;
781 	default:
782 		return nfserr_bad_xdr;
783 	}
784 	w &= ~NFS4_SHARE_ACCESS_MASK;
785 	if (!w)
786 		return nfs_ok;
787 	if (!argp->minorversion)
788 		return nfserr_bad_xdr;
789 	switch (w & NFS4_SHARE_WANT_MASK) {
790 	case NFS4_SHARE_WANT_NO_PREFERENCE:
791 	case NFS4_SHARE_WANT_READ_DELEG:
792 	case NFS4_SHARE_WANT_WRITE_DELEG:
793 	case NFS4_SHARE_WANT_ANY_DELEG:
794 	case NFS4_SHARE_WANT_NO_DELEG:
795 	case NFS4_SHARE_WANT_CANCEL:
796 		break;
797 	default:
798 		return nfserr_bad_xdr;
799 	}
800 	w &= ~NFS4_SHARE_WANT_MASK;
801 	if (!w)
802 		return nfs_ok;
803 
804 	if (!deleg_when)	/* open_downgrade */
805 		return nfserr_inval;
806 	switch (w) {
807 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
808 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
809 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
810 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
811 		return nfs_ok;
812 	}
813 xdr_error:
814 	return nfserr_bad_xdr;
815 }
816 
817 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
818 {
819 	__be32 *p;
820 
821 	READ_BUF(4);
822 	*x = be32_to_cpup(p++);
823 	/* Note: unlinke access bits, deny bits may be zero. */
824 	if (*x & ~NFS4_SHARE_DENY_BOTH)
825 		return nfserr_bad_xdr;
826 	return nfs_ok;
827 xdr_error:
828 	return nfserr_bad_xdr;
829 }
830 
831 static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
832 {
833 	__be32 *p;
834 
835 	READ_BUF(4);
836 	o->len = be32_to_cpup(p++);
837 
838 	if (o->len == 0 || o->len > NFS4_OPAQUE_LIMIT)
839 		return nfserr_bad_xdr;
840 
841 	READ_BUF(o->len);
842 	SAVEMEM(o->data, o->len);
843 	return nfs_ok;
844 xdr_error:
845 	return nfserr_bad_xdr;
846 }
847 
848 static __be32
849 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
850 {
851 	DECODE_HEAD;
852 	u32 dummy;
853 
854 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
855 	open->op_iattr.ia_valid = 0;
856 	open->op_openowner = NULL;
857 
858 	open->op_xdr_error = 0;
859 	/* seqid, share_access, share_deny, clientid, ownerlen */
860 	READ_BUF(4);
861 	open->op_seqid = be32_to_cpup(p++);
862 	/* decode, yet ignore deleg_when until supported */
863 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
864 					   &open->op_deleg_want, &dummy);
865 	if (status)
866 		goto xdr_error;
867 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
868 	if (status)
869 		goto xdr_error;
870 	READ_BUF(sizeof(clientid_t));
871 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
872 	status = nfsd4_decode_opaque(argp, &open->op_owner);
873 	if (status)
874 		goto xdr_error;
875 	READ_BUF(4);
876 	open->op_create = be32_to_cpup(p++);
877 	switch (open->op_create) {
878 	case NFS4_OPEN_NOCREATE:
879 		break;
880 	case NFS4_OPEN_CREATE:
881 		READ_BUF(4);
882 		open->op_createmode = be32_to_cpup(p++);
883 		switch (open->op_createmode) {
884 		case NFS4_CREATE_UNCHECKED:
885 		case NFS4_CREATE_GUARDED:
886 			status = nfsd4_decode_fattr(argp, open->op_bmval,
887 				&open->op_iattr, &open->op_acl, &open->op_label);
888 			if (status)
889 				goto out;
890 			break;
891 		case NFS4_CREATE_EXCLUSIVE:
892 			READ_BUF(NFS4_VERIFIER_SIZE);
893 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
894 			break;
895 		case NFS4_CREATE_EXCLUSIVE4_1:
896 			if (argp->minorversion < 1)
897 				goto xdr_error;
898 			READ_BUF(NFS4_VERIFIER_SIZE);
899 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
900 			status = nfsd4_decode_fattr(argp, open->op_bmval,
901 				&open->op_iattr, &open->op_acl, &open->op_label);
902 			if (status)
903 				goto out;
904 			break;
905 		default:
906 			goto xdr_error;
907 		}
908 		break;
909 	default:
910 		goto xdr_error;
911 	}
912 
913 	/* open_claim */
914 	READ_BUF(4);
915 	open->op_claim_type = be32_to_cpup(p++);
916 	switch (open->op_claim_type) {
917 	case NFS4_OPEN_CLAIM_NULL:
918 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
919 		READ_BUF(4);
920 		open->op_fname.len = be32_to_cpup(p++);
921 		READ_BUF(open->op_fname.len);
922 		SAVEMEM(open->op_fname.data, open->op_fname.len);
923 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
924 			return status;
925 		break;
926 	case NFS4_OPEN_CLAIM_PREVIOUS:
927 		READ_BUF(4);
928 		open->op_delegate_type = be32_to_cpup(p++);
929 		break;
930 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
931 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
932 		if (status)
933 			return status;
934 		READ_BUF(4);
935 		open->op_fname.len = be32_to_cpup(p++);
936 		READ_BUF(open->op_fname.len);
937 		SAVEMEM(open->op_fname.data, open->op_fname.len);
938 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
939 			return status;
940 		break;
941 	case NFS4_OPEN_CLAIM_FH:
942 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
943 		if (argp->minorversion < 1)
944 			goto xdr_error;
945 		/* void */
946 		break;
947 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
948 		if (argp->minorversion < 1)
949 			goto xdr_error;
950 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
951 		if (status)
952 			return status;
953 		break;
954 	default:
955 		goto xdr_error;
956 	}
957 
958 	DECODE_TAIL;
959 }
960 
961 static __be32
962 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
963 {
964 	DECODE_HEAD;
965 
966 	if (argp->minorversion >= 1)
967 		return nfserr_notsupp;
968 
969 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
970 	if (status)
971 		return status;
972 	READ_BUF(4);
973 	open_conf->oc_seqid = be32_to_cpup(p++);
974 
975 	DECODE_TAIL;
976 }
977 
978 static __be32
979 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
980 {
981 	DECODE_HEAD;
982 
983 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
984 	if (status)
985 		return status;
986 	READ_BUF(4);
987 	open_down->od_seqid = be32_to_cpup(p++);
988 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
989 					   &open_down->od_deleg_want, NULL);
990 	if (status)
991 		return status;
992 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
993 	if (status)
994 		return status;
995 	DECODE_TAIL;
996 }
997 
998 static __be32
999 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
1000 {
1001 	DECODE_HEAD;
1002 
1003 	READ_BUF(4);
1004 	putfh->pf_fhlen = be32_to_cpup(p++);
1005 	if (putfh->pf_fhlen > NFS4_FHSIZE)
1006 		goto xdr_error;
1007 	READ_BUF(putfh->pf_fhlen);
1008 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
1009 
1010 	DECODE_TAIL;
1011 }
1012 
1013 static __be32
1014 nfsd4_decode_putpubfh(struct nfsd4_compoundargs *argp, void *p)
1015 {
1016 	if (argp->minorversion == 0)
1017 		return nfs_ok;
1018 	return nfserr_notsupp;
1019 }
1020 
1021 static __be32
1022 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
1023 {
1024 	DECODE_HEAD;
1025 
1026 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
1027 	if (status)
1028 		return status;
1029 	READ_BUF(12);
1030 	p = xdr_decode_hyper(p, &read->rd_offset);
1031 	read->rd_length = be32_to_cpup(p++);
1032 
1033 	DECODE_TAIL;
1034 }
1035 
1036 static __be32
1037 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
1038 {
1039 	DECODE_HEAD;
1040 
1041 	READ_BUF(24);
1042 	p = xdr_decode_hyper(p, &readdir->rd_cookie);
1043 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
1044 	readdir->rd_dircount = be32_to_cpup(p++);
1045 	readdir->rd_maxcount = be32_to_cpup(p++);
1046 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
1047 		goto out;
1048 
1049 	DECODE_TAIL;
1050 }
1051 
1052 static __be32
1053 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
1054 {
1055 	DECODE_HEAD;
1056 
1057 	READ_BUF(4);
1058 	remove->rm_namelen = be32_to_cpup(p++);
1059 	READ_BUF(remove->rm_namelen);
1060 	SAVEMEM(remove->rm_name, remove->rm_namelen);
1061 	if ((status = check_filename(remove->rm_name, remove->rm_namelen)))
1062 		return status;
1063 
1064 	DECODE_TAIL;
1065 }
1066 
1067 static __be32
1068 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
1069 {
1070 	DECODE_HEAD;
1071 
1072 	READ_BUF(4);
1073 	rename->rn_snamelen = be32_to_cpup(p++);
1074 	READ_BUF(rename->rn_snamelen + 4);
1075 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1076 	rename->rn_tnamelen = be32_to_cpup(p++);
1077 	READ_BUF(rename->rn_tnamelen);
1078 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1079 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1080 		return status;
1081 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1082 		return status;
1083 
1084 	DECODE_TAIL;
1085 }
1086 
1087 static __be32
1088 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1089 {
1090 	DECODE_HEAD;
1091 
1092 	if (argp->minorversion >= 1)
1093 		return nfserr_notsupp;
1094 
1095 	READ_BUF(sizeof(clientid_t));
1096 	COPYMEM(clientid, sizeof(clientid_t));
1097 
1098 	DECODE_TAIL;
1099 }
1100 
1101 static __be32
1102 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1103 		     struct nfsd4_secinfo *secinfo)
1104 {
1105 	DECODE_HEAD;
1106 
1107 	READ_BUF(4);
1108 	secinfo->si_namelen = be32_to_cpup(p++);
1109 	READ_BUF(secinfo->si_namelen);
1110 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1111 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1112 	if (status)
1113 		return status;
1114 	DECODE_TAIL;
1115 }
1116 
1117 static __be32
1118 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1119 		     struct nfsd4_secinfo_no_name *sin)
1120 {
1121 	DECODE_HEAD;
1122 
1123 	READ_BUF(4);
1124 	sin->sin_style = be32_to_cpup(p++);
1125 	DECODE_TAIL;
1126 }
1127 
1128 static __be32
1129 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1130 {
1131 	__be32 status;
1132 
1133 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1134 	if (status)
1135 		return status;
1136 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1137 				  &setattr->sa_acl, &setattr->sa_label);
1138 }
1139 
1140 static __be32
1141 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1142 {
1143 	DECODE_HEAD;
1144 
1145 	if (argp->minorversion >= 1)
1146 		return nfserr_notsupp;
1147 
1148 	READ_BUF(NFS4_VERIFIER_SIZE);
1149 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1150 
1151 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1152 	if (status)
1153 		return nfserr_bad_xdr;
1154 	READ_BUF(8);
1155 	setclientid->se_callback_prog = be32_to_cpup(p++);
1156 	setclientid->se_callback_netid_len = be32_to_cpup(p++);
1157 
1158 	READ_BUF(setclientid->se_callback_netid_len + 4);
1159 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1160 	setclientid->se_callback_addr_len = be32_to_cpup(p++);
1161 
1162 	READ_BUF(setclientid->se_callback_addr_len + 4);
1163 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1164 	setclientid->se_callback_ident = be32_to_cpup(p++);
1165 
1166 	DECODE_TAIL;
1167 }
1168 
1169 static __be32
1170 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1171 {
1172 	DECODE_HEAD;
1173 
1174 	if (argp->minorversion >= 1)
1175 		return nfserr_notsupp;
1176 
1177 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1178 	COPYMEM(&scd_c->sc_clientid, 8);
1179 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1180 
1181 	DECODE_TAIL;
1182 }
1183 
1184 /* Also used for NVERIFY */
1185 static __be32
1186 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1187 {
1188 	DECODE_HEAD;
1189 
1190 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1191 		goto out;
1192 
1193 	/* For convenience's sake, we compare raw xdr'd attributes in
1194 	 * nfsd4_proc_verify */
1195 
1196 	READ_BUF(4);
1197 	verify->ve_attrlen = be32_to_cpup(p++);
1198 	READ_BUF(verify->ve_attrlen);
1199 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1200 
1201 	DECODE_TAIL;
1202 }
1203 
1204 static __be32
1205 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1206 {
1207 	int avail;
1208 	int len;
1209 	DECODE_HEAD;
1210 
1211 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1212 	if (status)
1213 		return status;
1214 	READ_BUF(16);
1215 	p = xdr_decode_hyper(p, &write->wr_offset);
1216 	write->wr_stable_how = be32_to_cpup(p++);
1217 	if (write->wr_stable_how > 2)
1218 		goto xdr_error;
1219 	write->wr_buflen = be32_to_cpup(p++);
1220 
1221 	/* Sorry .. no magic macros for this.. *
1222 	 * READ_BUF(write->wr_buflen);
1223 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1224 	 */
1225 	avail = (char*)argp->end - (char*)argp->p;
1226 	if (avail + argp->pagelen < write->wr_buflen) {
1227 		dprintk("NFSD: xdr error (%s:%d)\n",
1228 				__FILE__, __LINE__);
1229 		goto xdr_error;
1230 	}
1231 	write->wr_head.iov_base = p;
1232 	write->wr_head.iov_len = avail;
1233 	write->wr_pagelist = argp->pagelist;
1234 
1235 	len = XDR_QUADLEN(write->wr_buflen) << 2;
1236 	if (len >= avail) {
1237 		int pages;
1238 
1239 		len -= avail;
1240 
1241 		pages = len >> PAGE_SHIFT;
1242 		argp->pagelist += pages;
1243 		argp->pagelen -= pages * PAGE_SIZE;
1244 		len -= pages * PAGE_SIZE;
1245 
1246 		argp->p = (__be32 *)page_address(argp->pagelist[0]);
1247 		argp->pagelist++;
1248 		argp->end = argp->p + XDR_QUADLEN(PAGE_SIZE);
1249 	}
1250 	argp->p += XDR_QUADLEN(len);
1251 
1252 	DECODE_TAIL;
1253 }
1254 
1255 static __be32
1256 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1257 {
1258 	DECODE_HEAD;
1259 
1260 	if (argp->minorversion >= 1)
1261 		return nfserr_notsupp;
1262 
1263 	READ_BUF(12);
1264 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1265 	rlockowner->rl_owner.len = be32_to_cpup(p++);
1266 	READ_BUF(rlockowner->rl_owner.len);
1267 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1268 
1269 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1270 		return nfserr_inval;
1271 	DECODE_TAIL;
1272 }
1273 
1274 static __be32
1275 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1276 			 struct nfsd4_exchange_id *exid)
1277 {
1278 	int dummy, tmp;
1279 	DECODE_HEAD;
1280 
1281 	READ_BUF(NFS4_VERIFIER_SIZE);
1282 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1283 
1284 	status = nfsd4_decode_opaque(argp, &exid->clname);
1285 	if (status)
1286 		return nfserr_bad_xdr;
1287 
1288 	READ_BUF(4);
1289 	exid->flags = be32_to_cpup(p++);
1290 
1291 	/* Ignore state_protect4_a */
1292 	READ_BUF(4);
1293 	exid->spa_how = be32_to_cpup(p++);
1294 	switch (exid->spa_how) {
1295 	case SP4_NONE:
1296 		break;
1297 	case SP4_MACH_CRED:
1298 		/* spo_must_enforce */
1299 		READ_BUF(4);
1300 		dummy = be32_to_cpup(p++);
1301 		READ_BUF(dummy * 4);
1302 		p += dummy;
1303 
1304 		/* spo_must_allow */
1305 		READ_BUF(4);
1306 		dummy = be32_to_cpup(p++);
1307 		READ_BUF(dummy * 4);
1308 		p += dummy;
1309 		break;
1310 	case SP4_SSV:
1311 		/* ssp_ops */
1312 		READ_BUF(4);
1313 		dummy = be32_to_cpup(p++);
1314 		READ_BUF(dummy * 4);
1315 		p += dummy;
1316 
1317 		READ_BUF(4);
1318 		dummy = be32_to_cpup(p++);
1319 		READ_BUF(dummy * 4);
1320 		p += dummy;
1321 
1322 		/* ssp_hash_algs<> */
1323 		READ_BUF(4);
1324 		tmp = be32_to_cpup(p++);
1325 		while (tmp--) {
1326 			READ_BUF(4);
1327 			dummy = be32_to_cpup(p++);
1328 			READ_BUF(dummy);
1329 			p += XDR_QUADLEN(dummy);
1330 		}
1331 
1332 		/* ssp_encr_algs<> */
1333 		READ_BUF(4);
1334 		tmp = be32_to_cpup(p++);
1335 		while (tmp--) {
1336 			READ_BUF(4);
1337 			dummy = be32_to_cpup(p++);
1338 			READ_BUF(dummy);
1339 			p += XDR_QUADLEN(dummy);
1340 		}
1341 
1342 		/* ssp_window and ssp_num_gss_handles */
1343 		READ_BUF(8);
1344 		dummy = be32_to_cpup(p++);
1345 		dummy = be32_to_cpup(p++);
1346 		break;
1347 	default:
1348 		goto xdr_error;
1349 	}
1350 
1351 	/* Ignore Implementation ID */
1352 	READ_BUF(4);    /* nfs_impl_id4 array length */
1353 	dummy = be32_to_cpup(p++);
1354 
1355 	if (dummy > 1)
1356 		goto xdr_error;
1357 
1358 	if (dummy == 1) {
1359 		/* nii_domain */
1360 		READ_BUF(4);
1361 		dummy = be32_to_cpup(p++);
1362 		READ_BUF(dummy);
1363 		p += XDR_QUADLEN(dummy);
1364 
1365 		/* nii_name */
1366 		READ_BUF(4);
1367 		dummy = be32_to_cpup(p++);
1368 		READ_BUF(dummy);
1369 		p += XDR_QUADLEN(dummy);
1370 
1371 		/* nii_date */
1372 		READ_BUF(12);
1373 		p += 3;
1374 	}
1375 	DECODE_TAIL;
1376 }
1377 
1378 static __be32
1379 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1380 			    struct nfsd4_create_session *sess)
1381 {
1382 	DECODE_HEAD;
1383 	u32 dummy;
1384 
1385 	READ_BUF(16);
1386 	COPYMEM(&sess->clientid, 8);
1387 	sess->seqid = be32_to_cpup(p++);
1388 	sess->flags = be32_to_cpup(p++);
1389 
1390 	/* Fore channel attrs */
1391 	READ_BUF(28);
1392 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1393 	sess->fore_channel.maxreq_sz = be32_to_cpup(p++);
1394 	sess->fore_channel.maxresp_sz = be32_to_cpup(p++);
1395 	sess->fore_channel.maxresp_cached = be32_to_cpup(p++);
1396 	sess->fore_channel.maxops = be32_to_cpup(p++);
1397 	sess->fore_channel.maxreqs = be32_to_cpup(p++);
1398 	sess->fore_channel.nr_rdma_attrs = be32_to_cpup(p++);
1399 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1400 		READ_BUF(4);
1401 		sess->fore_channel.rdma_attrs = be32_to_cpup(p++);
1402 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1403 		dprintk("Too many fore channel attr bitmaps!\n");
1404 		goto xdr_error;
1405 	}
1406 
1407 	/* Back channel attrs */
1408 	READ_BUF(28);
1409 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1410 	sess->back_channel.maxreq_sz = be32_to_cpup(p++);
1411 	sess->back_channel.maxresp_sz = be32_to_cpup(p++);
1412 	sess->back_channel.maxresp_cached = be32_to_cpup(p++);
1413 	sess->back_channel.maxops = be32_to_cpup(p++);
1414 	sess->back_channel.maxreqs = be32_to_cpup(p++);
1415 	sess->back_channel.nr_rdma_attrs = be32_to_cpup(p++);
1416 	if (sess->back_channel.nr_rdma_attrs == 1) {
1417 		READ_BUF(4);
1418 		sess->back_channel.rdma_attrs = be32_to_cpup(p++);
1419 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1420 		dprintk("Too many back channel attr bitmaps!\n");
1421 		goto xdr_error;
1422 	}
1423 
1424 	READ_BUF(4);
1425 	sess->callback_prog = be32_to_cpup(p++);
1426 	nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1427 	DECODE_TAIL;
1428 }
1429 
1430 static __be32
1431 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1432 			     struct nfsd4_destroy_session *destroy_session)
1433 {
1434 	DECODE_HEAD;
1435 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1436 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1437 
1438 	DECODE_TAIL;
1439 }
1440 
1441 static __be32
1442 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1443 			  struct nfsd4_free_stateid *free_stateid)
1444 {
1445 	DECODE_HEAD;
1446 
1447 	READ_BUF(sizeof(stateid_t));
1448 	free_stateid->fr_stateid.si_generation = be32_to_cpup(p++);
1449 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1450 
1451 	DECODE_TAIL;
1452 }
1453 
1454 static __be32
1455 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1456 		      struct nfsd4_sequence *seq)
1457 {
1458 	DECODE_HEAD;
1459 
1460 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1461 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1462 	seq->seqid = be32_to_cpup(p++);
1463 	seq->slotid = be32_to_cpup(p++);
1464 	seq->maxslots = be32_to_cpup(p++);
1465 	seq->cachethis = be32_to_cpup(p++);
1466 
1467 	DECODE_TAIL;
1468 }
1469 
1470 static __be32
1471 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1472 {
1473 	int i;
1474 	__be32 *p, status;
1475 	struct nfsd4_test_stateid_id *stateid;
1476 
1477 	READ_BUF(4);
1478 	test_stateid->ts_num_ids = ntohl(*p++);
1479 
1480 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1481 
1482 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1483 		stateid = svcxdr_tmpalloc(argp, sizeof(*stateid));
1484 		if (!stateid) {
1485 			status = nfserrno(-ENOMEM);
1486 			goto out;
1487 		}
1488 
1489 		INIT_LIST_HEAD(&stateid->ts_id_list);
1490 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1491 
1492 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1493 		if (status)
1494 			goto out;
1495 	}
1496 
1497 	status = 0;
1498 out:
1499 	return status;
1500 xdr_error:
1501 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1502 	status = nfserr_bad_xdr;
1503 	goto out;
1504 }
1505 
1506 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1507 {
1508 	DECODE_HEAD;
1509 
1510 	READ_BUF(8);
1511 	COPYMEM(&dc->clientid, 8);
1512 
1513 	DECODE_TAIL;
1514 }
1515 
1516 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1517 {
1518 	DECODE_HEAD;
1519 
1520 	READ_BUF(4);
1521 	rc->rca_one_fs = be32_to_cpup(p++);
1522 
1523 	DECODE_TAIL;
1524 }
1525 
1526 #ifdef CONFIG_NFSD_PNFS
1527 static __be32
1528 nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp,
1529 		struct nfsd4_getdeviceinfo *gdev)
1530 {
1531 	DECODE_HEAD;
1532 	u32 num, i;
1533 
1534 	READ_BUF(sizeof(struct nfsd4_deviceid) + 3 * 4);
1535 	COPYMEM(&gdev->gd_devid, sizeof(struct nfsd4_deviceid));
1536 	gdev->gd_layout_type = be32_to_cpup(p++);
1537 	gdev->gd_maxcount = be32_to_cpup(p++);
1538 	num = be32_to_cpup(p++);
1539 	if (num) {
1540 		READ_BUF(4 * num);
1541 		gdev->gd_notify_types = be32_to_cpup(p++);
1542 		for (i = 1; i < num; i++) {
1543 			if (be32_to_cpup(p++)) {
1544 				status = nfserr_inval;
1545 				goto out;
1546 			}
1547 		}
1548 	}
1549 	DECODE_TAIL;
1550 }
1551 
1552 static __be32
1553 nfsd4_decode_layoutget(struct nfsd4_compoundargs *argp,
1554 		struct nfsd4_layoutget *lgp)
1555 {
1556 	DECODE_HEAD;
1557 
1558 	READ_BUF(36);
1559 	lgp->lg_signal = be32_to_cpup(p++);
1560 	lgp->lg_layout_type = be32_to_cpup(p++);
1561 	lgp->lg_seg.iomode = be32_to_cpup(p++);
1562 	p = xdr_decode_hyper(p, &lgp->lg_seg.offset);
1563 	p = xdr_decode_hyper(p, &lgp->lg_seg.length);
1564 	p = xdr_decode_hyper(p, &lgp->lg_minlength);
1565 	nfsd4_decode_stateid(argp, &lgp->lg_sid);
1566 	READ_BUF(4);
1567 	lgp->lg_maxcount = be32_to_cpup(p++);
1568 
1569 	DECODE_TAIL;
1570 }
1571 
1572 static __be32
1573 nfsd4_decode_layoutcommit(struct nfsd4_compoundargs *argp,
1574 		struct nfsd4_layoutcommit *lcp)
1575 {
1576 	DECODE_HEAD;
1577 	u32 timechange;
1578 
1579 	READ_BUF(20);
1580 	p = xdr_decode_hyper(p, &lcp->lc_seg.offset);
1581 	p = xdr_decode_hyper(p, &lcp->lc_seg.length);
1582 	lcp->lc_reclaim = be32_to_cpup(p++);
1583 	nfsd4_decode_stateid(argp, &lcp->lc_sid);
1584 	READ_BUF(4);
1585 	lcp->lc_newoffset = be32_to_cpup(p++);
1586 	if (lcp->lc_newoffset) {
1587 		READ_BUF(8);
1588 		p = xdr_decode_hyper(p, &lcp->lc_last_wr);
1589 	} else
1590 		lcp->lc_last_wr = 0;
1591 	READ_BUF(4);
1592 	timechange = be32_to_cpup(p++);
1593 	if (timechange) {
1594 		status = nfsd4_decode_time(argp, &lcp->lc_mtime);
1595 		if (status)
1596 			return status;
1597 	} else {
1598 		lcp->lc_mtime.tv_nsec = UTIME_NOW;
1599 	}
1600 	READ_BUF(8);
1601 	lcp->lc_layout_type = be32_to_cpup(p++);
1602 
1603 	/*
1604 	 * Save the layout update in XDR format and let the layout driver deal
1605 	 * with it later.
1606 	 */
1607 	lcp->lc_up_len = be32_to_cpup(p++);
1608 	if (lcp->lc_up_len > 0) {
1609 		READ_BUF(lcp->lc_up_len);
1610 		READMEM(lcp->lc_up_layout, lcp->lc_up_len);
1611 	}
1612 
1613 	DECODE_TAIL;
1614 }
1615 
1616 static __be32
1617 nfsd4_decode_layoutreturn(struct nfsd4_compoundargs *argp,
1618 		struct nfsd4_layoutreturn *lrp)
1619 {
1620 	DECODE_HEAD;
1621 
1622 	READ_BUF(16);
1623 	lrp->lr_reclaim = be32_to_cpup(p++);
1624 	lrp->lr_layout_type = be32_to_cpup(p++);
1625 	lrp->lr_seg.iomode = be32_to_cpup(p++);
1626 	lrp->lr_return_type = be32_to_cpup(p++);
1627 	if (lrp->lr_return_type == RETURN_FILE) {
1628 		READ_BUF(16);
1629 		p = xdr_decode_hyper(p, &lrp->lr_seg.offset);
1630 		p = xdr_decode_hyper(p, &lrp->lr_seg.length);
1631 		nfsd4_decode_stateid(argp, &lrp->lr_sid);
1632 		READ_BUF(4);
1633 		lrp->lrf_body_len = be32_to_cpup(p++);
1634 		if (lrp->lrf_body_len > 0) {
1635 			READ_BUF(lrp->lrf_body_len);
1636 			READMEM(lrp->lrf_body, lrp->lrf_body_len);
1637 		}
1638 	} else {
1639 		lrp->lr_seg.offset = 0;
1640 		lrp->lr_seg.length = NFS4_MAX_UINT64;
1641 	}
1642 
1643 	DECODE_TAIL;
1644 }
1645 #endif /* CONFIG_NFSD_PNFS */
1646 
1647 static __be32
1648 nfsd4_decode_fallocate(struct nfsd4_compoundargs *argp,
1649 		       struct nfsd4_fallocate *fallocate)
1650 {
1651 	DECODE_HEAD;
1652 
1653 	status = nfsd4_decode_stateid(argp, &fallocate->falloc_stateid);
1654 	if (status)
1655 		return status;
1656 
1657 	READ_BUF(16);
1658 	p = xdr_decode_hyper(p, &fallocate->falloc_offset);
1659 	xdr_decode_hyper(p, &fallocate->falloc_length);
1660 
1661 	DECODE_TAIL;
1662 }
1663 
1664 static __be32
1665 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
1666 {
1667 	DECODE_HEAD;
1668 
1669 	status = nfsd4_decode_stateid(argp, &seek->seek_stateid);
1670 	if (status)
1671 		return status;
1672 
1673 	READ_BUF(8 + 4);
1674 	p = xdr_decode_hyper(p, &seek->seek_offset);
1675 	seek->seek_whence = be32_to_cpup(p);
1676 
1677 	DECODE_TAIL;
1678 }
1679 
1680 static __be32
1681 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1682 {
1683 	return nfs_ok;
1684 }
1685 
1686 static __be32
1687 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1688 {
1689 	return nfserr_notsupp;
1690 }
1691 
1692 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1693 
1694 static nfsd4_dec nfsd4_dec_ops[] = {
1695 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1696 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1697 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1698 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1699 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1700 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1701 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1702 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1703 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1704 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1705 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1706 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1707 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1708 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1709 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1710 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1711 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1712 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1713 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1714 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1715 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_putpubfh,
1716 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1717 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1718 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1719 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1720 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1721 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1722 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1723 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1724 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1725 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1726 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1727 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1728 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1729 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1730 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1731 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1732 
1733 	/* new operations for NFSv4.1 */
1734 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_backchannel_ctl,
1735 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1736 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1737 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1738 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1739 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
1740 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1741 #ifdef CONFIG_NFSD_PNFS
1742 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_getdeviceinfo,
1743 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1744 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_layoutcommit,
1745 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_layoutget,
1746 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_layoutreturn,
1747 #else
1748 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1749 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1750 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1751 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1752 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1753 #endif
1754 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1755 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1756 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1757 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
1758 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1759 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
1760 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1761 
1762 	/* new operations for NFSv4.2 */
1763 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1764 	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_notsupp,
1765 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
1766 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1767 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1768 	[OP_LAYOUTERROR]	= (nfsd4_dec)nfsd4_decode_notsupp,
1769 	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1770 	[OP_OFFLOAD_CANCEL]	= (nfsd4_dec)nfsd4_decode_notsupp,
1771 	[OP_OFFLOAD_STATUS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1772 	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_notsupp,
1773 	[OP_SEEK]		= (nfsd4_dec)nfsd4_decode_seek,
1774 	[OP_WRITE_SAME]		= (nfsd4_dec)nfsd4_decode_notsupp,
1775 };
1776 
1777 static inline bool
1778 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
1779 {
1780 	if (op->opnum < FIRST_NFS4_OP)
1781 		return false;
1782 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
1783 		return false;
1784 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
1785 		return false;
1786 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
1787 		return false;
1788 	return true;
1789 }
1790 
1791 static __be32
1792 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1793 {
1794 	DECODE_HEAD;
1795 	struct nfsd4_op *op;
1796 	bool cachethis = false;
1797 	int auth_slack= argp->rqstp->rq_auth_slack;
1798 	int max_reply = auth_slack + 8; /* opcnt, status */
1799 	int readcount = 0;
1800 	int readbytes = 0;
1801 	int i;
1802 
1803 	READ_BUF(4);
1804 	argp->taglen = be32_to_cpup(p++);
1805 	READ_BUF(argp->taglen + 8);
1806 	SAVEMEM(argp->tag, argp->taglen);
1807 	argp->minorversion = be32_to_cpup(p++);
1808 	argp->opcnt = be32_to_cpup(p++);
1809 	max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
1810 
1811 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1812 		goto xdr_error;
1813 	if (argp->opcnt > 100)
1814 		goto xdr_error;
1815 
1816 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1817 		argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1818 		if (!argp->ops) {
1819 			argp->ops = argp->iops;
1820 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1821 			goto xdr_error;
1822 		}
1823 	}
1824 
1825 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
1826 		argp->opcnt = 0;
1827 
1828 	for (i = 0; i < argp->opcnt; i++) {
1829 		op = &argp->ops[i];
1830 		op->replay = NULL;
1831 
1832 		READ_BUF(4);
1833 		op->opnum = be32_to_cpup(p++);
1834 
1835 		if (nfsd4_opnum_in_range(argp, op))
1836 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
1837 		else {
1838 			op->opnum = OP_ILLEGAL;
1839 			op->status = nfserr_op_illegal;
1840 		}
1841 		/*
1842 		 * We'll try to cache the result in the DRC if any one
1843 		 * op in the compound wants to be cached:
1844 		 */
1845 		cachethis |= nfsd4_cache_this_op(op);
1846 
1847 		if (op->opnum == OP_READ) {
1848 			readcount++;
1849 			readbytes += nfsd4_max_reply(argp->rqstp, op);
1850 		} else
1851 			max_reply += nfsd4_max_reply(argp->rqstp, op);
1852 		/*
1853 		 * OP_LOCK may return a conflicting lock.  (Special case
1854 		 * because it will just skip encoding this if it runs
1855 		 * out of xdr buffer space, and it is the only operation
1856 		 * that behaves this way.)
1857 		 */
1858 		if (op->opnum == OP_LOCK)
1859 			max_reply += NFS4_OPAQUE_LIMIT;
1860 
1861 		if (op->status) {
1862 			argp->opcnt = i+1;
1863 			break;
1864 		}
1865 	}
1866 	/* Sessions make the DRC unnecessary: */
1867 	if (argp->minorversion)
1868 		cachethis = false;
1869 	svc_reserve(argp->rqstp, max_reply + readbytes);
1870 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1871 
1872 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
1873 		clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
1874 
1875 	DECODE_TAIL;
1876 }
1877 
1878 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode)
1879 {
1880 	if (IS_I_VERSION(inode)) {
1881 		p = xdr_encode_hyper(p, inode->i_version);
1882 	} else {
1883 		*p++ = cpu_to_be32(stat->ctime.tv_sec);
1884 		*p++ = cpu_to_be32(stat->ctime.tv_nsec);
1885 	}
1886 	return p;
1887 }
1888 
1889 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
1890 {
1891 	*p++ = cpu_to_be32(c->atomic);
1892 	if (c->change_supported) {
1893 		p = xdr_encode_hyper(p, c->before_change);
1894 		p = xdr_encode_hyper(p, c->after_change);
1895 	} else {
1896 		*p++ = cpu_to_be32(c->before_ctime_sec);
1897 		*p++ = cpu_to_be32(c->before_ctime_nsec);
1898 		*p++ = cpu_to_be32(c->after_ctime_sec);
1899 		*p++ = cpu_to_be32(c->after_ctime_nsec);
1900 	}
1901 	return p;
1902 }
1903 
1904 /* Encode as an array of strings the string given with components
1905  * separated @sep, escaped with esc_enter and esc_exit.
1906  */
1907 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
1908 					  char *components, char esc_enter,
1909 					  char esc_exit)
1910 {
1911 	__be32 *p;
1912 	__be32 pathlen;
1913 	int pathlen_offset;
1914 	int strlen, count=0;
1915 	char *str, *end, *next;
1916 
1917 	dprintk("nfsd4_encode_components(%s)\n", components);
1918 
1919 	pathlen_offset = xdr->buf->len;
1920 	p = xdr_reserve_space(xdr, 4);
1921 	if (!p)
1922 		return nfserr_resource;
1923 	p++; /* We will fill this in with @count later */
1924 
1925 	end = str = components;
1926 	while (*end) {
1927 		bool found_esc = false;
1928 
1929 		/* try to parse as esc_start, ..., esc_end, sep */
1930 		if (*str == esc_enter) {
1931 			for (; *end && (*end != esc_exit); end++)
1932 				/* find esc_exit or end of string */;
1933 			next = end + 1;
1934 			if (*end && (!*next || *next == sep)) {
1935 				str++;
1936 				found_esc = true;
1937 			}
1938 		}
1939 
1940 		if (!found_esc)
1941 			for (; *end && (*end != sep); end++)
1942 				/* find sep or end of string */;
1943 
1944 		strlen = end - str;
1945 		if (strlen) {
1946 			p = xdr_reserve_space(xdr, strlen + 4);
1947 			if (!p)
1948 				return nfserr_resource;
1949 			p = xdr_encode_opaque(p, str, strlen);
1950 			count++;
1951 		}
1952 		else
1953 			end++;
1954 		if (found_esc)
1955 			end = next;
1956 
1957 		str = end;
1958 	}
1959 	pathlen = htonl(count);
1960 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
1961 	return 0;
1962 }
1963 
1964 /* Encode as an array of strings the string given with components
1965  * separated @sep.
1966  */
1967 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
1968 				      char *components)
1969 {
1970 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
1971 }
1972 
1973 /*
1974  * encode a location element of a fs_locations structure
1975  */
1976 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
1977 					struct nfsd4_fs_location *location)
1978 {
1979 	__be32 status;
1980 
1981 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
1982 						'[', ']');
1983 	if (status)
1984 		return status;
1985 	status = nfsd4_encode_components(xdr, '/', location->path);
1986 	if (status)
1987 		return status;
1988 	return 0;
1989 }
1990 
1991 /*
1992  * Encode a path in RFC3530 'pathname4' format
1993  */
1994 static __be32 nfsd4_encode_path(struct xdr_stream *xdr,
1995 				const struct path *root,
1996 				const struct path *path)
1997 {
1998 	struct path cur = *path;
1999 	__be32 *p;
2000 	struct dentry **components = NULL;
2001 	unsigned int ncomponents = 0;
2002 	__be32 err = nfserr_jukebox;
2003 
2004 	dprintk("nfsd4_encode_components(");
2005 
2006 	path_get(&cur);
2007 	/* First walk the path up to the nfsd root, and store the
2008 	 * dentries/path components in an array.
2009 	 */
2010 	for (;;) {
2011 		if (cur.dentry == root->dentry && cur.mnt == root->mnt)
2012 			break;
2013 		if (cur.dentry == cur.mnt->mnt_root) {
2014 			if (follow_up(&cur))
2015 				continue;
2016 			goto out_free;
2017 		}
2018 		if ((ncomponents & 15) == 0) {
2019 			struct dentry **new;
2020 			new = krealloc(components,
2021 					sizeof(*new) * (ncomponents + 16),
2022 					GFP_KERNEL);
2023 			if (!new)
2024 				goto out_free;
2025 			components = new;
2026 		}
2027 		components[ncomponents++] = cur.dentry;
2028 		cur.dentry = dget_parent(cur.dentry);
2029 	}
2030 	err = nfserr_resource;
2031 	p = xdr_reserve_space(xdr, 4);
2032 	if (!p)
2033 		goto out_free;
2034 	*p++ = cpu_to_be32(ncomponents);
2035 
2036 	while (ncomponents) {
2037 		struct dentry *dentry = components[ncomponents - 1];
2038 		unsigned int len;
2039 
2040 		spin_lock(&dentry->d_lock);
2041 		len = dentry->d_name.len;
2042 		p = xdr_reserve_space(xdr, len + 4);
2043 		if (!p) {
2044 			spin_unlock(&dentry->d_lock);
2045 			goto out_free;
2046 		}
2047 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
2048 		dprintk("/%pd", dentry);
2049 		spin_unlock(&dentry->d_lock);
2050 		dput(dentry);
2051 		ncomponents--;
2052 	}
2053 
2054 	err = 0;
2055 out_free:
2056 	dprintk(")\n");
2057 	while (ncomponents)
2058 		dput(components[--ncomponents]);
2059 	kfree(components);
2060 	path_put(&cur);
2061 	return err;
2062 }
2063 
2064 static __be32 nfsd4_encode_fsloc_fsroot(struct xdr_stream *xdr,
2065 			struct svc_rqst *rqstp, const struct path *path)
2066 {
2067 	struct svc_export *exp_ps;
2068 	__be32 res;
2069 
2070 	exp_ps = rqst_find_fsidzero_export(rqstp);
2071 	if (IS_ERR(exp_ps))
2072 		return nfserrno(PTR_ERR(exp_ps));
2073 	res = nfsd4_encode_path(xdr, &exp_ps->ex_path, path);
2074 	exp_put(exp_ps);
2075 	return res;
2076 }
2077 
2078 /*
2079  *  encode a fs_locations structure
2080  */
2081 static __be32 nfsd4_encode_fs_locations(struct xdr_stream *xdr,
2082 			struct svc_rqst *rqstp, struct svc_export *exp)
2083 {
2084 	__be32 status;
2085 	int i;
2086 	__be32 *p;
2087 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
2088 
2089 	status = nfsd4_encode_fsloc_fsroot(xdr, rqstp, &exp->ex_path);
2090 	if (status)
2091 		return status;
2092 	p = xdr_reserve_space(xdr, 4);
2093 	if (!p)
2094 		return nfserr_resource;
2095 	*p++ = cpu_to_be32(fslocs->locations_count);
2096 	for (i=0; i<fslocs->locations_count; i++) {
2097 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
2098 		if (status)
2099 			return status;
2100 	}
2101 	return 0;
2102 }
2103 
2104 static u32 nfs4_file_type(umode_t mode)
2105 {
2106 	switch (mode & S_IFMT) {
2107 	case S_IFIFO:	return NF4FIFO;
2108 	case S_IFCHR:	return NF4CHR;
2109 	case S_IFDIR:	return NF4DIR;
2110 	case S_IFBLK:	return NF4BLK;
2111 	case S_IFLNK:	return NF4LNK;
2112 	case S_IFREG:	return NF4REG;
2113 	case S_IFSOCK:	return NF4SOCK;
2114 	default:	return NF4BAD;
2115 	};
2116 }
2117 
2118 static inline __be32
2119 nfsd4_encode_aclname(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2120 		     struct nfs4_ace *ace)
2121 {
2122 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
2123 		return nfs4_acl_write_who(xdr, ace->whotype);
2124 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
2125 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
2126 	else
2127 		return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
2128 }
2129 
2130 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
2131 			      FATTR4_WORD0_RDATTR_ERROR)
2132 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2133 
2134 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2135 static inline __be32
2136 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2137 			    void *context, int len)
2138 {
2139 	__be32 *p;
2140 
2141 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2142 	if (!p)
2143 		return nfserr_resource;
2144 
2145 	/*
2146 	 * For now we use a 0 here to indicate the null translation; in
2147 	 * the future we may place a call to translation code here.
2148 	 */
2149 	*p++ = cpu_to_be32(0); /* lfs */
2150 	*p++ = cpu_to_be32(0); /* pi */
2151 	p = xdr_encode_opaque(p, context, len);
2152 	return 0;
2153 }
2154 #else
2155 static inline __be32
2156 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2157 			    void *context, int len)
2158 { return 0; }
2159 #endif
2160 
2161 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *rdattr_err)
2162 {
2163 	/* As per referral draft:  */
2164 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2165 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2166 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2167 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2168 			*rdattr_err = NFSERR_MOVED;
2169 		else
2170 			return nfserr_moved;
2171 	}
2172 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2173 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2174 	return 0;
2175 }
2176 
2177 
2178 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2179 {
2180 	struct path path = exp->ex_path;
2181 	int err;
2182 
2183 	path_get(&path);
2184 	while (follow_up(&path)) {
2185 		if (path.dentry != path.mnt->mnt_root)
2186 			break;
2187 	}
2188 	err = vfs_getattr(&path, stat);
2189 	path_put(&path);
2190 	return err;
2191 }
2192 
2193 /*
2194  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2195  * ourselves.
2196  */
2197 static __be32
2198 nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
2199 		struct svc_export *exp,
2200 		struct dentry *dentry, u32 *bmval,
2201 		struct svc_rqst *rqstp, int ignore_crossmnt)
2202 {
2203 	u32 bmval0 = bmval[0];
2204 	u32 bmval1 = bmval[1];
2205 	u32 bmval2 = bmval[2];
2206 	struct kstat stat;
2207 	struct svc_fh *tempfh = NULL;
2208 	struct kstatfs statfs;
2209 	__be32 *p;
2210 	int starting_len = xdr->buf->len;
2211 	int attrlen_offset;
2212 	__be32 attrlen;
2213 	u32 dummy;
2214 	u64 dummy64;
2215 	u32 rdattr_err = 0;
2216 	__be32 status;
2217 	int err;
2218 	int aclsupport = 0;
2219 	struct nfs4_acl *acl = NULL;
2220 	void *context = NULL;
2221 	int contextlen;
2222 	bool contextsupport = false;
2223 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2224 	u32 minorversion = resp->cstate.minorversion;
2225 	struct path path = {
2226 		.mnt	= exp->ex_path.mnt,
2227 		.dentry	= dentry,
2228 	};
2229 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2230 
2231 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2232 	BUG_ON(bmval0 & ~nfsd_suppattrs0(minorversion));
2233 	BUG_ON(bmval1 & ~nfsd_suppattrs1(minorversion));
2234 	BUG_ON(bmval2 & ~nfsd_suppattrs2(minorversion));
2235 
2236 	if (exp->ex_fslocs.migrated) {
2237 		BUG_ON(bmval[2]);
2238 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &rdattr_err);
2239 		if (status)
2240 			goto out;
2241 	}
2242 
2243 	err = vfs_getattr(&path, &stat);
2244 	if (err)
2245 		goto out_nfserr;
2246 	if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
2247 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
2248 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2249 		       FATTR4_WORD1_SPACE_TOTAL))) {
2250 		err = vfs_statfs(&path, &statfs);
2251 		if (err)
2252 			goto out_nfserr;
2253 	}
2254 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2255 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2256 		status = nfserr_jukebox;
2257 		if (!tempfh)
2258 			goto out;
2259 		fh_init(tempfh, NFS4_FHSIZE);
2260 		status = fh_compose(tempfh, exp, dentry, NULL);
2261 		if (status)
2262 			goto out;
2263 		fhp = tempfh;
2264 	}
2265 	if (bmval0 & (FATTR4_WORD0_ACL | FATTR4_WORD0_ACLSUPPORT
2266 			| FATTR4_WORD0_SUPPORTED_ATTRS)) {
2267 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2268 		aclsupport = (err == 0);
2269 		if (bmval0 & FATTR4_WORD0_ACL) {
2270 			if (err == -EOPNOTSUPP)
2271 				bmval0 &= ~FATTR4_WORD0_ACL;
2272 			else if (err == -EINVAL) {
2273 				status = nfserr_attrnotsupp;
2274 				goto out;
2275 			} else if (err != 0)
2276 				goto out_nfserr;
2277 		}
2278 	}
2279 
2280 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2281 	if ((bmval[2] & FATTR4_WORD2_SECURITY_LABEL) ||
2282 			bmval[0] & FATTR4_WORD0_SUPPORTED_ATTRS) {
2283 		err = security_inode_getsecctx(dentry->d_inode,
2284 						&context, &contextlen);
2285 		contextsupport = (err == 0);
2286 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2287 			if (err == -EOPNOTSUPP)
2288 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2289 			else if (err)
2290 				goto out_nfserr;
2291 		}
2292 	}
2293 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2294 
2295 	if (bmval2) {
2296 		p = xdr_reserve_space(xdr, 16);
2297 		if (!p)
2298 			goto out_resource;
2299 		*p++ = cpu_to_be32(3);
2300 		*p++ = cpu_to_be32(bmval0);
2301 		*p++ = cpu_to_be32(bmval1);
2302 		*p++ = cpu_to_be32(bmval2);
2303 	} else if (bmval1) {
2304 		p = xdr_reserve_space(xdr, 12);
2305 		if (!p)
2306 			goto out_resource;
2307 		*p++ = cpu_to_be32(2);
2308 		*p++ = cpu_to_be32(bmval0);
2309 		*p++ = cpu_to_be32(bmval1);
2310 	} else {
2311 		p = xdr_reserve_space(xdr, 8);
2312 		if (!p)
2313 			goto out_resource;
2314 		*p++ = cpu_to_be32(1);
2315 		*p++ = cpu_to_be32(bmval0);
2316 	}
2317 
2318 	attrlen_offset = xdr->buf->len;
2319 	p = xdr_reserve_space(xdr, 4);
2320 	if (!p)
2321 		goto out_resource;
2322 	p++;                /* to be backfilled later */
2323 
2324 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2325 		u32 word0 = nfsd_suppattrs0(minorversion);
2326 		u32 word1 = nfsd_suppattrs1(minorversion);
2327 		u32 word2 = nfsd_suppattrs2(minorversion);
2328 
2329 		if (!aclsupport)
2330 			word0 &= ~FATTR4_WORD0_ACL;
2331 		if (!contextsupport)
2332 			word2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2333 		if (!word2) {
2334 			p = xdr_reserve_space(xdr, 12);
2335 			if (!p)
2336 				goto out_resource;
2337 			*p++ = cpu_to_be32(2);
2338 			*p++ = cpu_to_be32(word0);
2339 			*p++ = cpu_to_be32(word1);
2340 		} else {
2341 			p = xdr_reserve_space(xdr, 16);
2342 			if (!p)
2343 				goto out_resource;
2344 			*p++ = cpu_to_be32(3);
2345 			*p++ = cpu_to_be32(word0);
2346 			*p++ = cpu_to_be32(word1);
2347 			*p++ = cpu_to_be32(word2);
2348 		}
2349 	}
2350 	if (bmval0 & FATTR4_WORD0_TYPE) {
2351 		p = xdr_reserve_space(xdr, 4);
2352 		if (!p)
2353 			goto out_resource;
2354 		dummy = nfs4_file_type(stat.mode);
2355 		if (dummy == NF4BAD) {
2356 			status = nfserr_serverfault;
2357 			goto out;
2358 		}
2359 		*p++ = cpu_to_be32(dummy);
2360 	}
2361 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2362 		p = xdr_reserve_space(xdr, 4);
2363 		if (!p)
2364 			goto out_resource;
2365 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2366 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT);
2367 		else
2368 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT|
2369 						NFS4_FH_VOL_RENAME);
2370 	}
2371 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2372 		p = xdr_reserve_space(xdr, 8);
2373 		if (!p)
2374 			goto out_resource;
2375 		p = encode_change(p, &stat, dentry->d_inode);
2376 	}
2377 	if (bmval0 & FATTR4_WORD0_SIZE) {
2378 		p = xdr_reserve_space(xdr, 8);
2379 		if (!p)
2380 			goto out_resource;
2381 		p = xdr_encode_hyper(p, stat.size);
2382 	}
2383 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2384 		p = xdr_reserve_space(xdr, 4);
2385 		if (!p)
2386 			goto out_resource;
2387 		*p++ = cpu_to_be32(1);
2388 	}
2389 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2390 		p = xdr_reserve_space(xdr, 4);
2391 		if (!p)
2392 			goto out_resource;
2393 		*p++ = cpu_to_be32(1);
2394 	}
2395 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2396 		p = xdr_reserve_space(xdr, 4);
2397 		if (!p)
2398 			goto out_resource;
2399 		*p++ = cpu_to_be32(0);
2400 	}
2401 	if (bmval0 & FATTR4_WORD0_FSID) {
2402 		p = xdr_reserve_space(xdr, 16);
2403 		if (!p)
2404 			goto out_resource;
2405 		if (exp->ex_fslocs.migrated) {
2406 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
2407 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
2408 		} else switch(fsid_source(fhp)) {
2409 		case FSIDSOURCE_FSID:
2410 			p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
2411 			p = xdr_encode_hyper(p, (u64)0);
2412 			break;
2413 		case FSIDSOURCE_DEV:
2414 			*p++ = cpu_to_be32(0);
2415 			*p++ = cpu_to_be32(MAJOR(stat.dev));
2416 			*p++ = cpu_to_be32(0);
2417 			*p++ = cpu_to_be32(MINOR(stat.dev));
2418 			break;
2419 		case FSIDSOURCE_UUID:
2420 			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
2421 								EX_UUID_LEN);
2422 			break;
2423 		}
2424 	}
2425 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2426 		p = xdr_reserve_space(xdr, 4);
2427 		if (!p)
2428 			goto out_resource;
2429 		*p++ = cpu_to_be32(0);
2430 	}
2431 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2432 		p = xdr_reserve_space(xdr, 4);
2433 		if (!p)
2434 			goto out_resource;
2435 		*p++ = cpu_to_be32(nn->nfsd4_lease);
2436 	}
2437 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2438 		p = xdr_reserve_space(xdr, 4);
2439 		if (!p)
2440 			goto out_resource;
2441 		*p++ = cpu_to_be32(rdattr_err);
2442 	}
2443 	if (bmval0 & FATTR4_WORD0_ACL) {
2444 		struct nfs4_ace *ace;
2445 
2446 		if (acl == NULL) {
2447 			p = xdr_reserve_space(xdr, 4);
2448 			if (!p)
2449 				goto out_resource;
2450 
2451 			*p++ = cpu_to_be32(0);
2452 			goto out_acl;
2453 		}
2454 		p = xdr_reserve_space(xdr, 4);
2455 		if (!p)
2456 			goto out_resource;
2457 		*p++ = cpu_to_be32(acl->naces);
2458 
2459 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2460 			p = xdr_reserve_space(xdr, 4*3);
2461 			if (!p)
2462 				goto out_resource;
2463 			*p++ = cpu_to_be32(ace->type);
2464 			*p++ = cpu_to_be32(ace->flag);
2465 			*p++ = cpu_to_be32(ace->access_mask &
2466 							NFS4_ACE_MASK_ALL);
2467 			status = nfsd4_encode_aclname(xdr, rqstp, ace);
2468 			if (status)
2469 				goto out;
2470 		}
2471 	}
2472 out_acl:
2473 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2474 		p = xdr_reserve_space(xdr, 4);
2475 		if (!p)
2476 			goto out_resource;
2477 		*p++ = cpu_to_be32(aclsupport ?
2478 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2479 	}
2480 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2481 		p = xdr_reserve_space(xdr, 4);
2482 		if (!p)
2483 			goto out_resource;
2484 		*p++ = cpu_to_be32(1);
2485 	}
2486 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2487 		p = xdr_reserve_space(xdr, 4);
2488 		if (!p)
2489 			goto out_resource;
2490 		*p++ = cpu_to_be32(0);
2491 	}
2492 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2493 		p = xdr_reserve_space(xdr, 4);
2494 		if (!p)
2495 			goto out_resource;
2496 		*p++ = cpu_to_be32(1);
2497 	}
2498 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2499 		p = xdr_reserve_space(xdr, 4);
2500 		if (!p)
2501 			goto out_resource;
2502 		*p++ = cpu_to_be32(1);
2503 	}
2504 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2505 		p = xdr_reserve_space(xdr, fhp->fh_handle.fh_size + 4);
2506 		if (!p)
2507 			goto out_resource;
2508 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base,
2509 					fhp->fh_handle.fh_size);
2510 	}
2511 	if (bmval0 & FATTR4_WORD0_FILEID) {
2512 		p = xdr_reserve_space(xdr, 8);
2513 		if (!p)
2514 			goto out_resource;
2515 		p = xdr_encode_hyper(p, stat.ino);
2516 	}
2517 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2518 		p = xdr_reserve_space(xdr, 8);
2519 		if (!p)
2520 			goto out_resource;
2521 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2522 	}
2523 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2524 		p = xdr_reserve_space(xdr, 8);
2525 		if (!p)
2526 			goto out_resource;
2527 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2528 	}
2529 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2530 		p = xdr_reserve_space(xdr, 8);
2531 		if (!p)
2532 			goto out_resource;
2533 		p = xdr_encode_hyper(p, (u64) statfs.f_files);
2534 	}
2535 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2536 		status = nfsd4_encode_fs_locations(xdr, rqstp, exp);
2537 		if (status)
2538 			goto out;
2539 	}
2540 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2541 		p = xdr_reserve_space(xdr, 4);
2542 		if (!p)
2543 			goto out_resource;
2544 		*p++ = cpu_to_be32(1);
2545 	}
2546 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2547 		p = xdr_reserve_space(xdr, 8);
2548 		if (!p)
2549 			goto out_resource;
2550 		p = xdr_encode_hyper(p, exp->ex_path.mnt->mnt_sb->s_maxbytes);
2551 	}
2552 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2553 		p = xdr_reserve_space(xdr, 4);
2554 		if (!p)
2555 			goto out_resource;
2556 		*p++ = cpu_to_be32(255);
2557 	}
2558 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2559 		p = xdr_reserve_space(xdr, 4);
2560 		if (!p)
2561 			goto out_resource;
2562 		*p++ = cpu_to_be32(statfs.f_namelen);
2563 	}
2564 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2565 		p = xdr_reserve_space(xdr, 8);
2566 		if (!p)
2567 			goto out_resource;
2568 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2569 	}
2570 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2571 		p = xdr_reserve_space(xdr, 8);
2572 		if (!p)
2573 			goto out_resource;
2574 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2575 	}
2576 	if (bmval1 & FATTR4_WORD1_MODE) {
2577 		p = xdr_reserve_space(xdr, 4);
2578 		if (!p)
2579 			goto out_resource;
2580 		*p++ = cpu_to_be32(stat.mode & S_IALLUGO);
2581 	}
2582 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2583 		p = xdr_reserve_space(xdr, 4);
2584 		if (!p)
2585 			goto out_resource;
2586 		*p++ = cpu_to_be32(1);
2587 	}
2588 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2589 		p = xdr_reserve_space(xdr, 4);
2590 		if (!p)
2591 			goto out_resource;
2592 		*p++ = cpu_to_be32(stat.nlink);
2593 	}
2594 	if (bmval1 & FATTR4_WORD1_OWNER) {
2595 		status = nfsd4_encode_user(xdr, rqstp, stat.uid);
2596 		if (status)
2597 			goto out;
2598 	}
2599 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2600 		status = nfsd4_encode_group(xdr, rqstp, stat.gid);
2601 		if (status)
2602 			goto out;
2603 	}
2604 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2605 		p = xdr_reserve_space(xdr, 8);
2606 		if (!p)
2607 			goto out_resource;
2608 		*p++ = cpu_to_be32((u32) MAJOR(stat.rdev));
2609 		*p++ = cpu_to_be32((u32) MINOR(stat.rdev));
2610 	}
2611 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2612 		p = xdr_reserve_space(xdr, 8);
2613 		if (!p)
2614 			goto out_resource;
2615 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2616 		p = xdr_encode_hyper(p, dummy64);
2617 	}
2618 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2619 		p = xdr_reserve_space(xdr, 8);
2620 		if (!p)
2621 			goto out_resource;
2622 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2623 		p = xdr_encode_hyper(p, dummy64);
2624 	}
2625 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2626 		p = xdr_reserve_space(xdr, 8);
2627 		if (!p)
2628 			goto out_resource;
2629 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2630 		p = xdr_encode_hyper(p, dummy64);
2631 	}
2632 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2633 		p = xdr_reserve_space(xdr, 8);
2634 		if (!p)
2635 			goto out_resource;
2636 		dummy64 = (u64)stat.blocks << 9;
2637 		p = xdr_encode_hyper(p, dummy64);
2638 	}
2639 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2640 		p = xdr_reserve_space(xdr, 12);
2641 		if (!p)
2642 			goto out_resource;
2643 		p = xdr_encode_hyper(p, (s64)stat.atime.tv_sec);
2644 		*p++ = cpu_to_be32(stat.atime.tv_nsec);
2645 	}
2646 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2647 		p = xdr_reserve_space(xdr, 12);
2648 		if (!p)
2649 			goto out_resource;
2650 		*p++ = cpu_to_be32(0);
2651 		*p++ = cpu_to_be32(1);
2652 		*p++ = cpu_to_be32(0);
2653 	}
2654 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2655 		p = xdr_reserve_space(xdr, 12);
2656 		if (!p)
2657 			goto out_resource;
2658 		p = xdr_encode_hyper(p, (s64)stat.ctime.tv_sec);
2659 		*p++ = cpu_to_be32(stat.ctime.tv_nsec);
2660 	}
2661 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2662 		p = xdr_reserve_space(xdr, 12);
2663 		if (!p)
2664 			goto out_resource;
2665 		p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
2666 		*p++ = cpu_to_be32(stat.mtime.tv_nsec);
2667 	}
2668 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2669 		p = xdr_reserve_space(xdr, 8);
2670 		if (!p)
2671                 	goto out_resource;
2672 		/*
2673 		 * Get parent's attributes if not ignoring crossmount
2674 		 * and this is the root of a cross-mounted filesystem.
2675 		 */
2676 		if (ignore_crossmnt == 0 &&
2677 		    dentry == exp->ex_path.mnt->mnt_root)
2678 			get_parent_attributes(exp, &stat);
2679 		p = xdr_encode_hyper(p, stat.ino);
2680 	}
2681 #ifdef CONFIG_NFSD_PNFS
2682 	if ((bmval1 & FATTR4_WORD1_FS_LAYOUT_TYPES) ||
2683 	    (bmval2 & FATTR4_WORD2_LAYOUT_TYPES)) {
2684 		if (exp->ex_layout_type) {
2685 			p = xdr_reserve_space(xdr, 8);
2686 			if (!p)
2687 				goto out_resource;
2688 			*p++ = cpu_to_be32(1);
2689 			*p++ = cpu_to_be32(exp->ex_layout_type);
2690 		} else {
2691 			p = xdr_reserve_space(xdr, 4);
2692 			if (!p)
2693 				goto out_resource;
2694 			*p++ = cpu_to_be32(0);
2695 		}
2696 	}
2697 
2698 	if (bmval2 & FATTR4_WORD2_LAYOUT_BLKSIZE) {
2699 		p = xdr_reserve_space(xdr, 4);
2700 		if (!p)
2701 			goto out_resource;
2702 		*p++ = cpu_to_be32(stat.blksize);
2703 	}
2704 #endif /* CONFIG_NFSD_PNFS */
2705 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2706 		status = nfsd4_encode_security_label(xdr, rqstp, context,
2707 								contextlen);
2708 		if (status)
2709 			goto out;
2710 	}
2711 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2712 		p = xdr_reserve_space(xdr, 16);
2713 		if (!p)
2714 			goto out_resource;
2715 		*p++ = cpu_to_be32(3);
2716 		*p++ = cpu_to_be32(NFSD_SUPPATTR_EXCLCREAT_WORD0);
2717 		*p++ = cpu_to_be32(NFSD_SUPPATTR_EXCLCREAT_WORD1);
2718 		*p++ = cpu_to_be32(NFSD_SUPPATTR_EXCLCREAT_WORD2);
2719 	}
2720 
2721 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
2722 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
2723 	status = nfs_ok;
2724 
2725 out:
2726 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2727 	if (context)
2728 		security_release_secctx(context, contextlen);
2729 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2730 	kfree(acl);
2731 	if (tempfh) {
2732 		fh_put(tempfh);
2733 		kfree(tempfh);
2734 	}
2735 	if (status)
2736 		xdr_truncate_encode(xdr, starting_len);
2737 	return status;
2738 out_nfserr:
2739 	status = nfserrno(err);
2740 	goto out;
2741 out_resource:
2742 	status = nfserr_resource;
2743 	goto out;
2744 }
2745 
2746 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
2747 				struct xdr_buf *buf, __be32 *p, int bytes)
2748 {
2749 	xdr->scratch.iov_len = 0;
2750 	memset(buf, 0, sizeof(struct xdr_buf));
2751 	buf->head[0].iov_base = p;
2752 	buf->head[0].iov_len = 0;
2753 	buf->len = 0;
2754 	xdr->buf = buf;
2755 	xdr->iov = buf->head;
2756 	xdr->p = p;
2757 	xdr->end = (void *)p + bytes;
2758 	buf->buflen = bytes;
2759 }
2760 
2761 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
2762 			struct svc_fh *fhp, struct svc_export *exp,
2763 			struct dentry *dentry, u32 *bmval,
2764 			struct svc_rqst *rqstp, int ignore_crossmnt)
2765 {
2766 	struct xdr_buf dummy;
2767 	struct xdr_stream xdr;
2768 	__be32 ret;
2769 
2770 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
2771 	ret = nfsd4_encode_fattr(&xdr, fhp, exp, dentry, bmval, rqstp,
2772 							ignore_crossmnt);
2773 	*p = xdr.p;
2774 	return ret;
2775 }
2776 
2777 static inline int attributes_need_mount(u32 *bmval)
2778 {
2779 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2780 		return 1;
2781 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2782 		return 1;
2783 	return 0;
2784 }
2785 
2786 static __be32
2787 nfsd4_encode_dirent_fattr(struct xdr_stream *xdr, struct nfsd4_readdir *cd,
2788 			const char *name, int namlen)
2789 {
2790 	struct svc_export *exp = cd->rd_fhp->fh_export;
2791 	struct dentry *dentry;
2792 	__be32 nfserr;
2793 	int ignore_crossmnt = 0;
2794 
2795 	dentry = lookup_one_len(name, cd->rd_fhp->fh_dentry, namlen);
2796 	if (IS_ERR(dentry))
2797 		return nfserrno(PTR_ERR(dentry));
2798 	if (!dentry->d_inode) {
2799 		/*
2800 		 * nfsd_buffered_readdir drops the i_mutex between
2801 		 * readdir and calling this callback, leaving a window
2802 		 * where this directory entry could have gone away.
2803 		 */
2804 		dput(dentry);
2805 		return nfserr_noent;
2806 	}
2807 
2808 	exp_get(exp);
2809 	/*
2810 	 * In the case of a mountpoint, the client may be asking for
2811 	 * attributes that are only properties of the underlying filesystem
2812 	 * as opposed to the cross-mounted file system. In such a case,
2813 	 * we will not follow the cross mount and will fill the attribtutes
2814 	 * directly from the mountpoint dentry.
2815 	 */
2816 	if (nfsd_mountpoint(dentry, exp)) {
2817 		int err;
2818 
2819 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
2820 				&& !attributes_need_mount(cd->rd_bmval)) {
2821 			ignore_crossmnt = 1;
2822 			goto out_encode;
2823 		}
2824 		/*
2825 		 * Why the heck aren't we just using nfsd_lookup??
2826 		 * Different "."/".." handling?  Something else?
2827 		 * At least, add a comment here to explain....
2828 		 */
2829 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
2830 		if (err) {
2831 			nfserr = nfserrno(err);
2832 			goto out_put;
2833 		}
2834 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
2835 		if (nfserr)
2836 			goto out_put;
2837 
2838 	}
2839 out_encode:
2840 	nfserr = nfsd4_encode_fattr(xdr, NULL, exp, dentry, cd->rd_bmval,
2841 					cd->rd_rqstp, ignore_crossmnt);
2842 out_put:
2843 	dput(dentry);
2844 	exp_put(exp);
2845 	return nfserr;
2846 }
2847 
2848 static __be32 *
2849 nfsd4_encode_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
2850 {
2851 	__be32 *p;
2852 
2853 	p = xdr_reserve_space(xdr, 20);
2854 	if (!p)
2855 		return NULL;
2856 	*p++ = htonl(2);
2857 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
2858 	*p++ = htonl(0);			 /* bmval1 */
2859 
2860 	*p++ = htonl(4);     /* attribute length */
2861 	*p++ = nfserr;       /* no htonl */
2862 	return p;
2863 }
2864 
2865 static int
2866 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
2867 		    loff_t offset, u64 ino, unsigned int d_type)
2868 {
2869 	struct readdir_cd *ccd = ccdv;
2870 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
2871 	struct xdr_stream *xdr = cd->xdr;
2872 	int start_offset = xdr->buf->len;
2873 	int cookie_offset;
2874 	u32 name_and_cookie;
2875 	int entry_bytes;
2876 	__be32 nfserr = nfserr_toosmall;
2877 	__be64 wire_offset;
2878 	__be32 *p;
2879 
2880 	/* In nfsv4, "." and ".." never make it onto the wire.. */
2881 	if (name && isdotent(name, namlen)) {
2882 		cd->common.err = nfs_ok;
2883 		return 0;
2884 	}
2885 
2886 	if (cd->cookie_offset) {
2887 		wire_offset = cpu_to_be64(offset);
2888 		write_bytes_to_xdr_buf(xdr->buf, cd->cookie_offset,
2889 							&wire_offset, 8);
2890 	}
2891 
2892 	p = xdr_reserve_space(xdr, 4);
2893 	if (!p)
2894 		goto fail;
2895 	*p++ = xdr_one;                             /* mark entry present */
2896 	cookie_offset = xdr->buf->len;
2897 	p = xdr_reserve_space(xdr, 3*4 + namlen);
2898 	if (!p)
2899 		goto fail;
2900 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
2901 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
2902 
2903 	nfserr = nfsd4_encode_dirent_fattr(xdr, cd, name, namlen);
2904 	switch (nfserr) {
2905 	case nfs_ok:
2906 		break;
2907 	case nfserr_resource:
2908 		nfserr = nfserr_toosmall;
2909 		goto fail;
2910 	case nfserr_noent:
2911 		xdr_truncate_encode(xdr, start_offset);
2912 		goto skip_entry;
2913 	default:
2914 		/*
2915 		 * If the client requested the RDATTR_ERROR attribute,
2916 		 * we stuff the error code into this attribute
2917 		 * and continue.  If this attribute was not requested,
2918 		 * then in accordance with the spec, we fail the
2919 		 * entire READDIR operation(!)
2920 		 */
2921 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
2922 			goto fail;
2923 		p = nfsd4_encode_rdattr_error(xdr, nfserr);
2924 		if (p == NULL) {
2925 			nfserr = nfserr_toosmall;
2926 			goto fail;
2927 		}
2928 	}
2929 	nfserr = nfserr_toosmall;
2930 	entry_bytes = xdr->buf->len - start_offset;
2931 	if (entry_bytes > cd->rd_maxcount)
2932 		goto fail;
2933 	cd->rd_maxcount -= entry_bytes;
2934 	/*
2935 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so
2936 	 * let's always let through the first entry, at least:
2937 	 */
2938 	if (!cd->rd_dircount)
2939 		goto fail;
2940 	name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8;
2941 	if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
2942 		goto fail;
2943 	cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
2944 
2945 	cd->cookie_offset = cookie_offset;
2946 skip_entry:
2947 	cd->common.err = nfs_ok;
2948 	return 0;
2949 fail:
2950 	xdr_truncate_encode(xdr, start_offset);
2951 	cd->common.err = nfserr;
2952 	return -EINVAL;
2953 }
2954 
2955 static __be32
2956 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
2957 {
2958 	__be32 *p;
2959 
2960 	p = xdr_reserve_space(xdr, sizeof(stateid_t));
2961 	if (!p)
2962 		return nfserr_resource;
2963 	*p++ = cpu_to_be32(sid->si_generation);
2964 	p = xdr_encode_opaque_fixed(p, &sid->si_opaque,
2965 					sizeof(stateid_opaque_t));
2966 	return 0;
2967 }
2968 
2969 static __be32
2970 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
2971 {
2972 	struct xdr_stream *xdr = &resp->xdr;
2973 	__be32 *p;
2974 
2975 	if (!nfserr) {
2976 		p = xdr_reserve_space(xdr, 8);
2977 		if (!p)
2978 			return nfserr_resource;
2979 		*p++ = cpu_to_be32(access->ac_supported);
2980 		*p++ = cpu_to_be32(access->ac_resp_access);
2981 	}
2982 	return nfserr;
2983 }
2984 
2985 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
2986 {
2987 	struct xdr_stream *xdr = &resp->xdr;
2988 	__be32 *p;
2989 
2990 	if (!nfserr) {
2991 		p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 8);
2992 		if (!p)
2993 			return nfserr_resource;
2994 		p = xdr_encode_opaque_fixed(p, bcts->sessionid.data,
2995 						NFS4_MAX_SESSIONID_LEN);
2996 		*p++ = cpu_to_be32(bcts->dir);
2997 		/* Sorry, we do not yet support RDMA over 4.1: */
2998 		*p++ = cpu_to_be32(0);
2999 	}
3000 	return nfserr;
3001 }
3002 
3003 static __be32
3004 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
3005 {
3006 	struct xdr_stream *xdr = &resp->xdr;
3007 
3008 	if (!nfserr)
3009 		nfserr = nfsd4_encode_stateid(xdr, &close->cl_stateid);
3010 
3011 	return nfserr;
3012 }
3013 
3014 
3015 static __be32
3016 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
3017 {
3018 	struct xdr_stream *xdr = &resp->xdr;
3019 	__be32 *p;
3020 
3021 	if (!nfserr) {
3022 		p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3023 		if (!p)
3024 			return nfserr_resource;
3025 		p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
3026 						NFS4_VERIFIER_SIZE);
3027 	}
3028 	return nfserr;
3029 }
3030 
3031 static __be32
3032 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
3033 {
3034 	struct xdr_stream *xdr = &resp->xdr;
3035 	__be32 *p;
3036 
3037 	if (!nfserr) {
3038 		p = xdr_reserve_space(xdr, 32);
3039 		if (!p)
3040 			return nfserr_resource;
3041 		p = encode_cinfo(p, &create->cr_cinfo);
3042 		*p++ = cpu_to_be32(2);
3043 		*p++ = cpu_to_be32(create->cr_bmval[0]);
3044 		*p++ = cpu_to_be32(create->cr_bmval[1]);
3045 	}
3046 	return nfserr;
3047 }
3048 
3049 static __be32
3050 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
3051 {
3052 	struct svc_fh *fhp = getattr->ga_fhp;
3053 	struct xdr_stream *xdr = &resp->xdr;
3054 
3055 	if (nfserr)
3056 		return nfserr;
3057 
3058 	nfserr = nfsd4_encode_fattr(xdr, fhp, fhp->fh_export, fhp->fh_dentry,
3059 				    getattr->ga_bmval,
3060 				    resp->rqstp, 0);
3061 	return nfserr;
3062 }
3063 
3064 static __be32
3065 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
3066 {
3067 	struct xdr_stream *xdr = &resp->xdr;
3068 	struct svc_fh *fhp = *fhpp;
3069 	unsigned int len;
3070 	__be32 *p;
3071 
3072 	if (!nfserr) {
3073 		len = fhp->fh_handle.fh_size;
3074 		p = xdr_reserve_space(xdr, len + 4);
3075 		if (!p)
3076 			return nfserr_resource;
3077 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base, len);
3078 	}
3079 	return nfserr;
3080 }
3081 
3082 /*
3083 * Including all fields other than the name, a LOCK4denied structure requires
3084 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
3085 */
3086 static __be32
3087 nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld)
3088 {
3089 	struct xdr_netobj *conf = &ld->ld_owner;
3090 	__be32 *p;
3091 
3092 again:
3093 	p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len));
3094 	if (!p) {
3095 		/*
3096 		 * Don't fail to return the result just because we can't
3097 		 * return the conflicting open:
3098 		 */
3099 		if (conf->len) {
3100 			kfree(conf->data);
3101 			conf->len = 0;
3102 			conf->data = NULL;
3103 			goto again;
3104 		}
3105 		return nfserr_resource;
3106 	}
3107 	p = xdr_encode_hyper(p, ld->ld_start);
3108 	p = xdr_encode_hyper(p, ld->ld_length);
3109 	*p++ = cpu_to_be32(ld->ld_type);
3110 	if (conf->len) {
3111 		p = xdr_encode_opaque_fixed(p, &ld->ld_clientid, 8);
3112 		p = xdr_encode_opaque(p, conf->data, conf->len);
3113 		kfree(conf->data);
3114 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
3115 		p = xdr_encode_hyper(p, (u64)0); /* clientid */
3116 		*p++ = cpu_to_be32(0); /* length of owner name */
3117 	}
3118 	return nfserr_denied;
3119 }
3120 
3121 static __be32
3122 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
3123 {
3124 	struct xdr_stream *xdr = &resp->xdr;
3125 
3126 	if (!nfserr)
3127 		nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid);
3128 	else if (nfserr == nfserr_denied)
3129 		nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied);
3130 
3131 	return nfserr;
3132 }
3133 
3134 static __be32
3135 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
3136 {
3137 	struct xdr_stream *xdr = &resp->xdr;
3138 
3139 	if (nfserr == nfserr_denied)
3140 		nfsd4_encode_lock_denied(xdr, &lockt->lt_denied);
3141 	return nfserr;
3142 }
3143 
3144 static __be32
3145 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
3146 {
3147 	struct xdr_stream *xdr = &resp->xdr;
3148 
3149 	if (!nfserr)
3150 		nfserr = nfsd4_encode_stateid(xdr, &locku->lu_stateid);
3151 
3152 	return nfserr;
3153 }
3154 
3155 
3156 static __be32
3157 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
3158 {
3159 	struct xdr_stream *xdr = &resp->xdr;
3160 	__be32 *p;
3161 
3162 	if (!nfserr) {
3163 		p = xdr_reserve_space(xdr, 20);
3164 		if (!p)
3165 			return nfserr_resource;
3166 		p = encode_cinfo(p, &link->li_cinfo);
3167 	}
3168 	return nfserr;
3169 }
3170 
3171 
3172 static __be32
3173 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
3174 {
3175 	struct xdr_stream *xdr = &resp->xdr;
3176 	__be32 *p;
3177 
3178 	if (nfserr)
3179 		goto out;
3180 
3181 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
3182 	if (nfserr)
3183 		goto out;
3184 	p = xdr_reserve_space(xdr, 40);
3185 	if (!p)
3186 		return nfserr_resource;
3187 	p = encode_cinfo(p, &open->op_cinfo);
3188 	*p++ = cpu_to_be32(open->op_rflags);
3189 	*p++ = cpu_to_be32(2);
3190 	*p++ = cpu_to_be32(open->op_bmval[0]);
3191 	*p++ = cpu_to_be32(open->op_bmval[1]);
3192 	*p++ = cpu_to_be32(open->op_delegate_type);
3193 
3194 	switch (open->op_delegate_type) {
3195 	case NFS4_OPEN_DELEGATE_NONE:
3196 		break;
3197 	case NFS4_OPEN_DELEGATE_READ:
3198 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3199 		if (nfserr)
3200 			return nfserr;
3201 		p = xdr_reserve_space(xdr, 20);
3202 		if (!p)
3203 			return nfserr_resource;
3204 		*p++ = cpu_to_be32(open->op_recall);
3205 
3206 		/*
3207 		 * TODO: ACE's in delegations
3208 		 */
3209 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3210 		*p++ = cpu_to_be32(0);
3211 		*p++ = cpu_to_be32(0);
3212 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3213 		break;
3214 	case NFS4_OPEN_DELEGATE_WRITE:
3215 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3216 		if (nfserr)
3217 			return nfserr;
3218 		p = xdr_reserve_space(xdr, 32);
3219 		if (!p)
3220 			return nfserr_resource;
3221 		*p++ = cpu_to_be32(0);
3222 
3223 		/*
3224 		 * TODO: space_limit's in delegations
3225 		 */
3226 		*p++ = cpu_to_be32(NFS4_LIMIT_SIZE);
3227 		*p++ = cpu_to_be32(~(u32)0);
3228 		*p++ = cpu_to_be32(~(u32)0);
3229 
3230 		/*
3231 		 * TODO: ACE's in delegations
3232 		 */
3233 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3234 		*p++ = cpu_to_be32(0);
3235 		*p++ = cpu_to_be32(0);
3236 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3237 		break;
3238 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
3239 		switch (open->op_why_no_deleg) {
3240 		case WND4_CONTENTION:
3241 		case WND4_RESOURCE:
3242 			p = xdr_reserve_space(xdr, 8);
3243 			if (!p)
3244 				return nfserr_resource;
3245 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3246 			/* deleg signaling not supported yet: */
3247 			*p++ = cpu_to_be32(0);
3248 			break;
3249 		default:
3250 			p = xdr_reserve_space(xdr, 4);
3251 			if (!p)
3252 				return nfserr_resource;
3253 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3254 		}
3255 		break;
3256 	default:
3257 		BUG();
3258 	}
3259 	/* XXX save filehandle here */
3260 out:
3261 	return nfserr;
3262 }
3263 
3264 static __be32
3265 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
3266 {
3267 	struct xdr_stream *xdr = &resp->xdr;
3268 
3269 	if (!nfserr)
3270 		nfserr = nfsd4_encode_stateid(xdr, &oc->oc_resp_stateid);
3271 
3272 	return nfserr;
3273 }
3274 
3275 static __be32
3276 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
3277 {
3278 	struct xdr_stream *xdr = &resp->xdr;
3279 
3280 	if (!nfserr)
3281 		nfserr = nfsd4_encode_stateid(xdr, &od->od_stateid);
3282 
3283 	return nfserr;
3284 }
3285 
3286 static __be32 nfsd4_encode_splice_read(
3287 				struct nfsd4_compoundres *resp,
3288 				struct nfsd4_read *read,
3289 				struct file *file, unsigned long maxcount)
3290 {
3291 	struct xdr_stream *xdr = &resp->xdr;
3292 	struct xdr_buf *buf = xdr->buf;
3293 	u32 eof;
3294 	int space_left;
3295 	__be32 nfserr;
3296 	__be32 *p = xdr->p - 2;
3297 
3298 	/* Make sure there will be room for padding if needed */
3299 	if (xdr->end - xdr->p < 1)
3300 		return nfserr_resource;
3301 
3302 	nfserr = nfsd_splice_read(read->rd_rqstp, file,
3303 				  read->rd_offset, &maxcount);
3304 	if (nfserr) {
3305 		/*
3306 		 * nfsd_splice_actor may have already messed with the
3307 		 * page length; reset it so as not to confuse
3308 		 * xdr_truncate_encode:
3309 		 */
3310 		buf->page_len = 0;
3311 		return nfserr;
3312 	}
3313 
3314 	eof = (read->rd_offset + maxcount >=
3315 	       read->rd_fhp->fh_dentry->d_inode->i_size);
3316 
3317 	*(p++) = htonl(eof);
3318 	*(p++) = htonl(maxcount);
3319 
3320 	buf->page_len = maxcount;
3321 	buf->len += maxcount;
3322 	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
3323 							/ PAGE_SIZE;
3324 
3325 	/* Use rest of head for padding and remaining ops: */
3326 	buf->tail[0].iov_base = xdr->p;
3327 	buf->tail[0].iov_len = 0;
3328 	xdr->iov = buf->tail;
3329 	if (maxcount&3) {
3330 		int pad = 4 - (maxcount&3);
3331 
3332 		*(xdr->p++) = 0;
3333 
3334 		buf->tail[0].iov_base += maxcount&3;
3335 		buf->tail[0].iov_len = pad;
3336 		buf->len += pad;
3337 	}
3338 
3339 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
3340 				buf->buflen - buf->len);
3341 	buf->buflen = buf->len + space_left;
3342 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
3343 
3344 	return 0;
3345 }
3346 
3347 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
3348 				 struct nfsd4_read *read,
3349 				 struct file *file, unsigned long maxcount)
3350 {
3351 	struct xdr_stream *xdr = &resp->xdr;
3352 	u32 eof;
3353 	int v;
3354 	int starting_len = xdr->buf->len - 8;
3355 	long len;
3356 	int thislen;
3357 	__be32 nfserr;
3358 	__be32 tmp;
3359 	__be32 *p;
3360 	u32 zzz = 0;
3361 	int pad;
3362 
3363 	len = maxcount;
3364 	v = 0;
3365 
3366 	thislen = min_t(long, len, ((void *)xdr->end - (void *)xdr->p));
3367 	p = xdr_reserve_space(xdr, (thislen+3)&~3);
3368 	WARN_ON_ONCE(!p);
3369 	resp->rqstp->rq_vec[v].iov_base = p;
3370 	resp->rqstp->rq_vec[v].iov_len = thislen;
3371 	v++;
3372 	len -= thislen;
3373 
3374 	while (len) {
3375 		thislen = min_t(long, len, PAGE_SIZE);
3376 		p = xdr_reserve_space(xdr, (thislen+3)&~3);
3377 		WARN_ON_ONCE(!p);
3378 		resp->rqstp->rq_vec[v].iov_base = p;
3379 		resp->rqstp->rq_vec[v].iov_len = thislen;
3380 		v++;
3381 		len -= thislen;
3382 	}
3383 	read->rd_vlen = v;
3384 
3385 	nfserr = nfsd_readv(file, read->rd_offset, resp->rqstp->rq_vec,
3386 			read->rd_vlen, &maxcount);
3387 	if (nfserr)
3388 		return nfserr;
3389 	xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3));
3390 
3391 	eof = (read->rd_offset + maxcount >=
3392 	       read->rd_fhp->fh_dentry->d_inode->i_size);
3393 
3394 	tmp = htonl(eof);
3395 	write_bytes_to_xdr_buf(xdr->buf, starting_len    , &tmp, 4);
3396 	tmp = htonl(maxcount);
3397 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
3398 
3399 	pad = (maxcount&3) ? 4 - (maxcount&3) : 0;
3400 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 8 + maxcount,
3401 								&zzz, pad);
3402 	return 0;
3403 
3404 }
3405 
3406 static __be32
3407 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
3408 		  struct nfsd4_read *read)
3409 {
3410 	unsigned long maxcount;
3411 	struct xdr_stream *xdr = &resp->xdr;
3412 	struct file *file = read->rd_filp;
3413 	int starting_len = xdr->buf->len;
3414 	struct raparms *ra;
3415 	__be32 *p;
3416 	__be32 err;
3417 
3418 	if (nfserr)
3419 		return nfserr;
3420 
3421 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
3422 	if (!p) {
3423 		WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
3424 		return nfserr_resource;
3425 	}
3426 	if (resp->xdr.buf->page_len && test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
3427 		WARN_ON_ONCE(1);
3428 		return nfserr_resource;
3429 	}
3430 	xdr_commit_encode(xdr);
3431 
3432 	maxcount = svc_max_payload(resp->rqstp);
3433 	maxcount = min_t(unsigned long, maxcount, (xdr->buf->buflen - xdr->buf->len));
3434 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
3435 
3436 	if (!read->rd_filp) {
3437 		err = nfsd_get_tmp_read_open(resp->rqstp, read->rd_fhp,
3438 						&file, &ra);
3439 		if (err)
3440 			goto err_truncate;
3441 	}
3442 
3443 	if (file->f_op->splice_read && test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
3444 		err = nfsd4_encode_splice_read(resp, read, file, maxcount);
3445 	else
3446 		err = nfsd4_encode_readv(resp, read, file, maxcount);
3447 
3448 	if (!read->rd_filp)
3449 		nfsd_put_tmp_read_open(file, ra);
3450 
3451 err_truncate:
3452 	if (err)
3453 		xdr_truncate_encode(xdr, starting_len);
3454 	return err;
3455 }
3456 
3457 static __be32
3458 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3459 {
3460 	int maxcount;
3461 	__be32 wire_count;
3462 	int zero = 0;
3463 	struct xdr_stream *xdr = &resp->xdr;
3464 	int length_offset = xdr->buf->len;
3465 	__be32 *p;
3466 
3467 	if (nfserr)
3468 		return nfserr;
3469 
3470 	p = xdr_reserve_space(xdr, 4);
3471 	if (!p)
3472 		return nfserr_resource;
3473 	maxcount = PAGE_SIZE;
3474 
3475 	p = xdr_reserve_space(xdr, maxcount);
3476 	if (!p)
3477 		return nfserr_resource;
3478 	/*
3479 	 * XXX: By default, the ->readlink() VFS op will truncate symlinks
3480 	 * if they would overflow the buffer.  Is this kosher in NFSv4?  If
3481 	 * not, one easy fix is: if ->readlink() precisely fills the buffer,
3482 	 * assume that truncation occurred, and return NFS4ERR_RESOURCE.
3483 	 */
3484 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
3485 						(char *)p, &maxcount);
3486 	if (nfserr == nfserr_isdir)
3487 		nfserr = nfserr_inval;
3488 	if (nfserr) {
3489 		xdr_truncate_encode(xdr, length_offset);
3490 		return nfserr;
3491 	}
3492 
3493 	wire_count = htonl(maxcount);
3494 	write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
3495 	xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
3496 	if (maxcount & 3)
3497 		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
3498 						&zero, 4 - (maxcount&3));
3499 	return 0;
3500 }
3501 
3502 static __be32
3503 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3504 {
3505 	int maxcount;
3506 	int bytes_left;
3507 	loff_t offset;
3508 	__be64 wire_offset;
3509 	struct xdr_stream *xdr = &resp->xdr;
3510 	int starting_len = xdr->buf->len;
3511 	__be32 *p;
3512 
3513 	if (nfserr)
3514 		return nfserr;
3515 
3516 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3517 	if (!p)
3518 		return nfserr_resource;
3519 
3520 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3521 	*p++ = cpu_to_be32(0);
3522 	*p++ = cpu_to_be32(0);
3523 	resp->xdr.buf->head[0].iov_len = ((char *)resp->xdr.p)
3524 				- (char *)resp->xdr.buf->head[0].iov_base;
3525 
3526 	/*
3527 	 * Number of bytes left for directory entries allowing for the
3528 	 * final 8 bytes of the readdir and a following failed op:
3529 	 */
3530 	bytes_left = xdr->buf->buflen - xdr->buf->len
3531 			- COMPOUND_ERR_SLACK_SPACE - 8;
3532 	if (bytes_left < 0) {
3533 		nfserr = nfserr_resource;
3534 		goto err_no_verf;
3535 	}
3536 	maxcount = min_t(u32, readdir->rd_maxcount, INT_MAX);
3537 	/*
3538 	 * Note the rfc defines rd_maxcount as the size of the
3539 	 * READDIR4resok structure, which includes the verifier above
3540 	 * and the 8 bytes encoded at the end of this function:
3541 	 */
3542 	if (maxcount < 16) {
3543 		nfserr = nfserr_toosmall;
3544 		goto err_no_verf;
3545 	}
3546 	maxcount = min_t(int, maxcount-16, bytes_left);
3547 
3548 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
3549 	if (!readdir->rd_dircount)
3550 		readdir->rd_dircount = INT_MAX;
3551 
3552 	readdir->xdr = xdr;
3553 	readdir->rd_maxcount = maxcount;
3554 	readdir->common.err = 0;
3555 	readdir->cookie_offset = 0;
3556 
3557 	offset = readdir->rd_cookie;
3558 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3559 			      &offset,
3560 			      &readdir->common, nfsd4_encode_dirent);
3561 	if (nfserr == nfs_ok &&
3562 	    readdir->common.err == nfserr_toosmall &&
3563 	    xdr->buf->len == starting_len + 8) {
3564 		/* nothing encoded; which limit did we hit?: */
3565 		if (maxcount - 16 < bytes_left)
3566 			/* It was the fault of rd_maxcount: */
3567 			nfserr = nfserr_toosmall;
3568 		else
3569 			/* We ran out of buffer space: */
3570 			nfserr = nfserr_resource;
3571 	}
3572 	if (nfserr)
3573 		goto err_no_verf;
3574 
3575 	if (readdir->cookie_offset) {
3576 		wire_offset = cpu_to_be64(offset);
3577 		write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset,
3578 							&wire_offset, 8);
3579 	}
3580 
3581 	p = xdr_reserve_space(xdr, 8);
3582 	if (!p) {
3583 		WARN_ON_ONCE(1);
3584 		goto err_no_verf;
3585 	}
3586 	*p++ = 0;	/* no more entries */
3587 	*p++ = htonl(readdir->common.err == nfserr_eof);
3588 
3589 	return 0;
3590 err_no_verf:
3591 	xdr_truncate_encode(xdr, starting_len);
3592 	return nfserr;
3593 }
3594 
3595 static __be32
3596 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3597 {
3598 	struct xdr_stream *xdr = &resp->xdr;
3599 	__be32 *p;
3600 
3601 	if (!nfserr) {
3602 		p = xdr_reserve_space(xdr, 20);
3603 		if (!p)
3604 			return nfserr_resource;
3605 		p = encode_cinfo(p, &remove->rm_cinfo);
3606 	}
3607 	return nfserr;
3608 }
3609 
3610 static __be32
3611 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3612 {
3613 	struct xdr_stream *xdr = &resp->xdr;
3614 	__be32 *p;
3615 
3616 	if (!nfserr) {
3617 		p = xdr_reserve_space(xdr, 40);
3618 		if (!p)
3619 			return nfserr_resource;
3620 		p = encode_cinfo(p, &rename->rn_sinfo);
3621 		p = encode_cinfo(p, &rename->rn_tinfo);
3622 	}
3623 	return nfserr;
3624 }
3625 
3626 static __be32
3627 nfsd4_do_encode_secinfo(struct xdr_stream *xdr,
3628 			 __be32 nfserr, struct svc_export *exp)
3629 {
3630 	u32 i, nflavs, supported;
3631 	struct exp_flavor_info *flavs;
3632 	struct exp_flavor_info def_flavs[2];
3633 	__be32 *p, *flavorsp;
3634 	static bool report = true;
3635 
3636 	if (nfserr)
3637 		goto out;
3638 	nfserr = nfserr_resource;
3639 	if (exp->ex_nflavors) {
3640 		flavs = exp->ex_flavors;
3641 		nflavs = exp->ex_nflavors;
3642 	} else { /* Handling of some defaults in absence of real secinfo: */
3643 		flavs = def_flavs;
3644 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3645 			nflavs = 2;
3646 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3647 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3648 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3649 			nflavs = 1;
3650 			flavs[0].pseudoflavor
3651 					= svcauth_gss_flavor(exp->ex_client);
3652 		} else {
3653 			nflavs = 1;
3654 			flavs[0].pseudoflavor
3655 					= exp->ex_client->flavour->flavour;
3656 		}
3657 	}
3658 
3659 	supported = 0;
3660 	p = xdr_reserve_space(xdr, 4);
3661 	if (!p)
3662 		goto out;
3663 	flavorsp = p++;		/* to be backfilled later */
3664 
3665 	for (i = 0; i < nflavs; i++) {
3666 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
3667 		struct rpcsec_gss_info info;
3668 
3669 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
3670 			supported++;
3671 			p = xdr_reserve_space(xdr, 4 + 4 +
3672 					      XDR_LEN(info.oid.len) + 4 + 4);
3673 			if (!p)
3674 				goto out;
3675 			*p++ = cpu_to_be32(RPC_AUTH_GSS);
3676 			p = xdr_encode_opaque(p,  info.oid.data, info.oid.len);
3677 			*p++ = cpu_to_be32(info.qop);
3678 			*p++ = cpu_to_be32(info.service);
3679 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
3680 			supported++;
3681 			p = xdr_reserve_space(xdr, 4);
3682 			if (!p)
3683 				goto out;
3684 			*p++ = cpu_to_be32(pf);
3685 		} else {
3686 			if (report)
3687 				pr_warn("NFS: SECINFO: security flavor %u "
3688 					"is not supported\n", pf);
3689 		}
3690 	}
3691 
3692 	if (nflavs != supported)
3693 		report = false;
3694 	*flavorsp = htonl(supported);
3695 	nfserr = 0;
3696 out:
3697 	if (exp)
3698 		exp_put(exp);
3699 	return nfserr;
3700 }
3701 
3702 static __be32
3703 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3704 		     struct nfsd4_secinfo *secinfo)
3705 {
3706 	struct xdr_stream *xdr = &resp->xdr;
3707 
3708 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->si_exp);
3709 }
3710 
3711 static __be32
3712 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3713 		     struct nfsd4_secinfo_no_name *secinfo)
3714 {
3715 	struct xdr_stream *xdr = &resp->xdr;
3716 
3717 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->sin_exp);
3718 }
3719 
3720 /*
3721  * The SETATTR encode routine is special -- it always encodes a bitmap,
3722  * regardless of the error status.
3723  */
3724 static __be32
3725 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3726 {
3727 	struct xdr_stream *xdr = &resp->xdr;
3728 	__be32 *p;
3729 
3730 	p = xdr_reserve_space(xdr, 16);
3731 	if (!p)
3732 		return nfserr_resource;
3733 	if (nfserr) {
3734 		*p++ = cpu_to_be32(3);
3735 		*p++ = cpu_to_be32(0);
3736 		*p++ = cpu_to_be32(0);
3737 		*p++ = cpu_to_be32(0);
3738 	}
3739 	else {
3740 		*p++ = cpu_to_be32(3);
3741 		*p++ = cpu_to_be32(setattr->sa_bmval[0]);
3742 		*p++ = cpu_to_be32(setattr->sa_bmval[1]);
3743 		*p++ = cpu_to_be32(setattr->sa_bmval[2]);
3744 	}
3745 	return nfserr;
3746 }
3747 
3748 static __be32
3749 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3750 {
3751 	struct xdr_stream *xdr = &resp->xdr;
3752 	__be32 *p;
3753 
3754 	if (!nfserr) {
3755 		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
3756 		if (!p)
3757 			return nfserr_resource;
3758 		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
3759 		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
3760 						NFS4_VERIFIER_SIZE);
3761 	}
3762 	else if (nfserr == nfserr_clid_inuse) {
3763 		p = xdr_reserve_space(xdr, 8);
3764 		if (!p)
3765 			return nfserr_resource;
3766 		*p++ = cpu_to_be32(0);
3767 		*p++ = cpu_to_be32(0);
3768 	}
3769 	return nfserr;
3770 }
3771 
3772 static __be32
3773 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3774 {
3775 	struct xdr_stream *xdr = &resp->xdr;
3776 	__be32 *p;
3777 
3778 	if (!nfserr) {
3779 		p = xdr_reserve_space(xdr, 16);
3780 		if (!p)
3781 			return nfserr_resource;
3782 		*p++ = cpu_to_be32(write->wr_bytes_written);
3783 		*p++ = cpu_to_be32(write->wr_how_written);
3784 		p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
3785 							NFS4_VERIFIER_SIZE);
3786 	}
3787 	return nfserr;
3788 }
3789 
3790 static const u32 nfs4_minimal_spo_must_enforce[2] = {
3791 	[1] = 1 << (OP_BIND_CONN_TO_SESSION - 32) |
3792 	      1 << (OP_EXCHANGE_ID - 32) |
3793 	      1 << (OP_CREATE_SESSION - 32) |
3794 	      1 << (OP_DESTROY_SESSION - 32) |
3795 	      1 << (OP_DESTROY_CLIENTID - 32)
3796 };
3797 
3798 static __be32
3799 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
3800 			 struct nfsd4_exchange_id *exid)
3801 {
3802 	struct xdr_stream *xdr = &resp->xdr;
3803 	__be32 *p;
3804 	char *major_id;
3805 	char *server_scope;
3806 	int major_id_sz;
3807 	int server_scope_sz;
3808 	uint64_t minor_id = 0;
3809 
3810 	if (nfserr)
3811 		return nfserr;
3812 
3813 	major_id = utsname()->nodename;
3814 	major_id_sz = strlen(major_id);
3815 	server_scope = utsname()->nodename;
3816 	server_scope_sz = strlen(server_scope);
3817 
3818 	p = xdr_reserve_space(xdr,
3819 		8 /* eir_clientid */ +
3820 		4 /* eir_sequenceid */ +
3821 		4 /* eir_flags */ +
3822 		4 /* spr_how */);
3823 	if (!p)
3824 		return nfserr_resource;
3825 
3826 	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
3827 	*p++ = cpu_to_be32(exid->seqid);
3828 	*p++ = cpu_to_be32(exid->flags);
3829 
3830 	*p++ = cpu_to_be32(exid->spa_how);
3831 
3832 	switch (exid->spa_how) {
3833 	case SP4_NONE:
3834 		break;
3835 	case SP4_MACH_CRED:
3836 		/* spo_must_enforce, spo_must_allow */
3837 		p = xdr_reserve_space(xdr, 16);
3838 		if (!p)
3839 			return nfserr_resource;
3840 
3841 		/* spo_must_enforce bitmap: */
3842 		*p++ = cpu_to_be32(2);
3843 		*p++ = cpu_to_be32(nfs4_minimal_spo_must_enforce[0]);
3844 		*p++ = cpu_to_be32(nfs4_minimal_spo_must_enforce[1]);
3845 		/* empty spo_must_allow bitmap: */
3846 		*p++ = cpu_to_be32(0);
3847 
3848 		break;
3849 	default:
3850 		WARN_ON_ONCE(1);
3851 	}
3852 
3853 	p = xdr_reserve_space(xdr,
3854 		8 /* so_minor_id */ +
3855 		4 /* so_major_id.len */ +
3856 		(XDR_QUADLEN(major_id_sz) * 4) +
3857 		4 /* eir_server_scope.len */ +
3858 		(XDR_QUADLEN(server_scope_sz) * 4) +
3859 		4 /* eir_server_impl_id.count (0) */);
3860 	if (!p)
3861 		return nfserr_resource;
3862 
3863 	/* The server_owner struct */
3864 	p = xdr_encode_hyper(p, minor_id);      /* Minor id */
3865 	/* major id */
3866 	p = xdr_encode_opaque(p, major_id, major_id_sz);
3867 
3868 	/* Server scope */
3869 	p = xdr_encode_opaque(p, server_scope, server_scope_sz);
3870 
3871 	/* Implementation id */
3872 	*p++ = cpu_to_be32(0);	/* zero length nfs_impl_id4 array */
3873 	return 0;
3874 }
3875 
3876 static __be32
3877 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
3878 			    struct nfsd4_create_session *sess)
3879 {
3880 	struct xdr_stream *xdr = &resp->xdr;
3881 	__be32 *p;
3882 
3883 	if (nfserr)
3884 		return nfserr;
3885 
3886 	p = xdr_reserve_space(xdr, 24);
3887 	if (!p)
3888 		return nfserr_resource;
3889 	p = xdr_encode_opaque_fixed(p, sess->sessionid.data,
3890 					NFS4_MAX_SESSIONID_LEN);
3891 	*p++ = cpu_to_be32(sess->seqid);
3892 	*p++ = cpu_to_be32(sess->flags);
3893 
3894 	p = xdr_reserve_space(xdr, 28);
3895 	if (!p)
3896 		return nfserr_resource;
3897 	*p++ = cpu_to_be32(0); /* headerpadsz */
3898 	*p++ = cpu_to_be32(sess->fore_channel.maxreq_sz);
3899 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_sz);
3900 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_cached);
3901 	*p++ = cpu_to_be32(sess->fore_channel.maxops);
3902 	*p++ = cpu_to_be32(sess->fore_channel.maxreqs);
3903 	*p++ = cpu_to_be32(sess->fore_channel.nr_rdma_attrs);
3904 
3905 	if (sess->fore_channel.nr_rdma_attrs) {
3906 		p = xdr_reserve_space(xdr, 4);
3907 		if (!p)
3908 			return nfserr_resource;
3909 		*p++ = cpu_to_be32(sess->fore_channel.rdma_attrs);
3910 	}
3911 
3912 	p = xdr_reserve_space(xdr, 28);
3913 	if (!p)
3914 		return nfserr_resource;
3915 	*p++ = cpu_to_be32(0); /* headerpadsz */
3916 	*p++ = cpu_to_be32(sess->back_channel.maxreq_sz);
3917 	*p++ = cpu_to_be32(sess->back_channel.maxresp_sz);
3918 	*p++ = cpu_to_be32(sess->back_channel.maxresp_cached);
3919 	*p++ = cpu_to_be32(sess->back_channel.maxops);
3920 	*p++ = cpu_to_be32(sess->back_channel.maxreqs);
3921 	*p++ = cpu_to_be32(sess->back_channel.nr_rdma_attrs);
3922 
3923 	if (sess->back_channel.nr_rdma_attrs) {
3924 		p = xdr_reserve_space(xdr, 4);
3925 		if (!p)
3926 			return nfserr_resource;
3927 		*p++ = cpu_to_be32(sess->back_channel.rdma_attrs);
3928 	}
3929 	return 0;
3930 }
3931 
3932 static __be32
3933 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
3934 		      struct nfsd4_sequence *seq)
3935 {
3936 	struct xdr_stream *xdr = &resp->xdr;
3937 	__be32 *p;
3938 
3939 	if (nfserr)
3940 		return nfserr;
3941 
3942 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 20);
3943 	if (!p)
3944 		return nfserr_resource;
3945 	p = xdr_encode_opaque_fixed(p, seq->sessionid.data,
3946 					NFS4_MAX_SESSIONID_LEN);
3947 	*p++ = cpu_to_be32(seq->seqid);
3948 	*p++ = cpu_to_be32(seq->slotid);
3949 	/* Note slotid's are numbered from zero: */
3950 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_highest_slotid */
3951 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_target_highest_slotid */
3952 	*p++ = cpu_to_be32(seq->status_flags);
3953 
3954 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
3955 	return 0;
3956 }
3957 
3958 static __be32
3959 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
3960 			  struct nfsd4_test_stateid *test_stateid)
3961 {
3962 	struct xdr_stream *xdr = &resp->xdr;
3963 	struct nfsd4_test_stateid_id *stateid, *next;
3964 	__be32 *p;
3965 
3966 	if (nfserr)
3967 		return nfserr;
3968 
3969 	p = xdr_reserve_space(xdr, 4 + (4 * test_stateid->ts_num_ids));
3970 	if (!p)
3971 		return nfserr_resource;
3972 	*p++ = htonl(test_stateid->ts_num_ids);
3973 
3974 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
3975 		*p++ = stateid->ts_id_status;
3976 	}
3977 
3978 	return nfserr;
3979 }
3980 
3981 #ifdef CONFIG_NFSD_PNFS
3982 static __be32
3983 nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3984 		struct nfsd4_getdeviceinfo *gdev)
3985 {
3986 	struct xdr_stream *xdr = &resp->xdr;
3987 	const struct nfsd4_layout_ops *ops =
3988 		nfsd4_layout_ops[gdev->gd_layout_type];
3989 	u32 starting_len = xdr->buf->len, needed_len;
3990 	__be32 *p;
3991 
3992 	dprintk("%s: err %d\n", __func__, nfserr);
3993 	if (nfserr)
3994 		goto out;
3995 
3996 	nfserr = nfserr_resource;
3997 	p = xdr_reserve_space(xdr, 4);
3998 	if (!p)
3999 		goto out;
4000 
4001 	*p++ = cpu_to_be32(gdev->gd_layout_type);
4002 
4003 	/* If maxcount is 0 then just update notifications */
4004 	if (gdev->gd_maxcount != 0) {
4005 		nfserr = ops->encode_getdeviceinfo(xdr, gdev);
4006 		if (nfserr) {
4007 			/*
4008 			 * We don't bother to burden the layout drivers with
4009 			 * enforcing gd_maxcount, just tell the client to
4010 			 * come back with a bigger buffer if it's not enough.
4011 			 */
4012 			if (xdr->buf->len + 4 > gdev->gd_maxcount)
4013 				goto toosmall;
4014 			goto out;
4015 		}
4016 	}
4017 
4018 	nfserr = nfserr_resource;
4019 	if (gdev->gd_notify_types) {
4020 		p = xdr_reserve_space(xdr, 4 + 4);
4021 		if (!p)
4022 			goto out;
4023 		*p++ = cpu_to_be32(1);			/* bitmap length */
4024 		*p++ = cpu_to_be32(gdev->gd_notify_types);
4025 	} else {
4026 		p = xdr_reserve_space(xdr, 4);
4027 		if (!p)
4028 			goto out;
4029 		*p++ = 0;
4030 	}
4031 
4032 	nfserr = 0;
4033 out:
4034 	kfree(gdev->gd_device);
4035 	dprintk("%s: done: %d\n", __func__, be32_to_cpu(nfserr));
4036 	return nfserr;
4037 
4038 toosmall:
4039 	dprintk("%s: maxcount too small\n", __func__);
4040 	needed_len = xdr->buf->len + 4 /* notifications */;
4041 	xdr_truncate_encode(xdr, starting_len);
4042 	p = xdr_reserve_space(xdr, 4);
4043 	if (!p) {
4044 		nfserr = nfserr_resource;
4045 	} else {
4046 		*p++ = cpu_to_be32(needed_len);
4047 		nfserr = nfserr_toosmall;
4048 	}
4049 	goto out;
4050 }
4051 
4052 static __be32
4053 nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr,
4054 		struct nfsd4_layoutget *lgp)
4055 {
4056 	struct xdr_stream *xdr = &resp->xdr;
4057 	const struct nfsd4_layout_ops *ops =
4058 		nfsd4_layout_ops[lgp->lg_layout_type];
4059 	__be32 *p;
4060 
4061 	dprintk("%s: err %d\n", __func__, nfserr);
4062 	if (nfserr)
4063 		goto out;
4064 
4065 	nfserr = nfserr_resource;
4066 	p = xdr_reserve_space(xdr, 36 + sizeof(stateid_opaque_t));
4067 	if (!p)
4068 		goto out;
4069 
4070 	*p++ = cpu_to_be32(1);	/* we always set return-on-close */
4071 	*p++ = cpu_to_be32(lgp->lg_sid.si_generation);
4072 	p = xdr_encode_opaque_fixed(p, &lgp->lg_sid.si_opaque,
4073 				    sizeof(stateid_opaque_t));
4074 
4075 	*p++ = cpu_to_be32(1);	/* we always return a single layout */
4076 	p = xdr_encode_hyper(p, lgp->lg_seg.offset);
4077 	p = xdr_encode_hyper(p, lgp->lg_seg.length);
4078 	*p++ = cpu_to_be32(lgp->lg_seg.iomode);
4079 	*p++ = cpu_to_be32(lgp->lg_layout_type);
4080 
4081 	nfserr = ops->encode_layoutget(xdr, lgp);
4082 out:
4083 	kfree(lgp->lg_content);
4084 	return nfserr;
4085 }
4086 
4087 static __be32
4088 nfsd4_encode_layoutcommit(struct nfsd4_compoundres *resp, __be32 nfserr,
4089 			  struct nfsd4_layoutcommit *lcp)
4090 {
4091 	struct xdr_stream *xdr = &resp->xdr;
4092 	__be32 *p;
4093 
4094 	if (nfserr)
4095 		return nfserr;
4096 
4097 	p = xdr_reserve_space(xdr, 4);
4098 	if (!p)
4099 		return nfserr_resource;
4100 	*p++ = cpu_to_be32(lcp->lc_size_chg);
4101 	if (lcp->lc_size_chg) {
4102 		p = xdr_reserve_space(xdr, 8);
4103 		if (!p)
4104 			return nfserr_resource;
4105 		p = xdr_encode_hyper(p, lcp->lc_newsize);
4106 	}
4107 
4108 	return nfs_ok;
4109 }
4110 
4111 static __be32
4112 nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
4113 		struct nfsd4_layoutreturn *lrp)
4114 {
4115 	struct xdr_stream *xdr = &resp->xdr;
4116 	__be32 *p;
4117 
4118 	if (nfserr)
4119 		return nfserr;
4120 
4121 	p = xdr_reserve_space(xdr, 4);
4122 	if (!p)
4123 		return nfserr_resource;
4124 	*p++ = cpu_to_be32(lrp->lrs_present);
4125 	if (lrp->lrs_present)
4126 		nfsd4_encode_stateid(xdr, &lrp->lr_sid);
4127 	return nfs_ok;
4128 }
4129 #endif /* CONFIG_NFSD_PNFS */
4130 
4131 static __be32
4132 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
4133 		  struct nfsd4_seek *seek)
4134 {
4135 	__be32 *p;
4136 
4137 	if (nfserr)
4138 		return nfserr;
4139 
4140 	p = xdr_reserve_space(&resp->xdr, 4 + 8);
4141 	*p++ = cpu_to_be32(seek->seek_eof);
4142 	p = xdr_encode_hyper(p, seek->seek_pos);
4143 
4144 	return nfserr;
4145 }
4146 
4147 static __be32
4148 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
4149 {
4150 	return nfserr;
4151 }
4152 
4153 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
4154 
4155 /*
4156  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
4157  * since we don't need to filter out obsolete ops as this is
4158  * done in the decoding phase.
4159  */
4160 static nfsd4_enc nfsd4_enc_ops[] = {
4161 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
4162 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
4163 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
4164 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
4165 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
4166 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4167 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
4168 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
4169 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
4170 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
4171 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
4172 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
4173 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
4174 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
4175 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4176 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
4177 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
4178 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
4179 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
4180 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4181 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
4182 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4183 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
4184 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
4185 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
4186 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
4187 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
4188 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
4189 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
4190 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
4191 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
4192 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
4193 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
4194 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
4195 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4196 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
4197 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
4198 
4199 	/* NFSv4.1 operations */
4200 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
4201 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
4202 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
4203 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
4204 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
4205 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
4206 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4207 #ifdef CONFIG_NFSD_PNFS
4208 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_getdeviceinfo,
4209 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4210 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_layoutcommit,
4211 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_layoutget,
4212 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_layoutreturn,
4213 #else
4214 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
4215 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4216 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
4217 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
4218 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4219 #endif
4220 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
4221 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
4222 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
4223 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
4224 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4225 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
4226 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
4227 
4228 	/* NFSv4.2 operations */
4229 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4230 	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_noop,
4231 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
4232 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4233 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
4234 	[OP_LAYOUTERROR]	= (nfsd4_enc)nfsd4_encode_noop,
4235 	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,
4236 	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,
4237 	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_noop,
4238 	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_noop,
4239 	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,
4240 	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,
4241 };
4242 
4243 /*
4244  * Calculate whether we still have space to encode repsize bytes.
4245  * There are two considerations:
4246  *     - For NFS versions >=4.1, the size of the reply must stay within
4247  *       session limits
4248  *     - For all NFS versions, we must stay within limited preallocated
4249  *       buffer space.
4250  *
4251  * This is called before the operation is processed, so can only provide
4252  * an upper estimate.  For some nonidempotent operations (such as
4253  * getattr), it's not necessarily a problem if that estimate is wrong,
4254  * as we can fail it after processing without significant side effects.
4255  */
4256 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
4257 {
4258 	struct xdr_buf *buf = &resp->rqstp->rq_res;
4259 	struct nfsd4_slot *slot = resp->cstate.slot;
4260 
4261 	if (buf->len + respsize <= buf->buflen)
4262 		return nfs_ok;
4263 	if (!nfsd4_has_session(&resp->cstate))
4264 		return nfserr_resource;
4265 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
4266 		WARN_ON_ONCE(1);
4267 		return nfserr_rep_too_big_to_cache;
4268 	}
4269 	return nfserr_rep_too_big;
4270 }
4271 
4272 void
4273 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
4274 {
4275 	struct xdr_stream *xdr = &resp->xdr;
4276 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
4277 	struct svc_rqst *rqstp = resp->rqstp;
4278 	int post_err_offset;
4279 	nfsd4_enc encoder;
4280 	__be32 *p;
4281 
4282 	p = xdr_reserve_space(xdr, 8);
4283 	if (!p) {
4284 		WARN_ON_ONCE(1);
4285 		return;
4286 	}
4287 	*p++ = cpu_to_be32(op->opnum);
4288 	post_err_offset = xdr->buf->len;
4289 
4290 	if (op->opnum == OP_ILLEGAL)
4291 		goto status;
4292 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
4293 	       !nfsd4_enc_ops[op->opnum]);
4294 	encoder = nfsd4_enc_ops[op->opnum];
4295 	op->status = encoder(resp, op->status, &op->u);
4296 	xdr_commit_encode(xdr);
4297 
4298 	/* nfsd4_check_resp_size guarantees enough room for error status */
4299 	if (!op->status) {
4300 		int space_needed = 0;
4301 		if (!nfsd4_last_compound_op(rqstp))
4302 			space_needed = COMPOUND_ERR_SLACK_SPACE;
4303 		op->status = nfsd4_check_resp_size(resp, space_needed);
4304 	}
4305 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
4306 		struct nfsd4_slot *slot = resp->cstate.slot;
4307 
4308 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
4309 			op->status = nfserr_rep_too_big_to_cache;
4310 		else
4311 			op->status = nfserr_rep_too_big;
4312 	}
4313 	if (op->status == nfserr_resource ||
4314 	    op->status == nfserr_rep_too_big ||
4315 	    op->status == nfserr_rep_too_big_to_cache) {
4316 		/*
4317 		 * The operation may have already been encoded or
4318 		 * partially encoded.  No op returns anything additional
4319 		 * in the case of one of these three errors, so we can
4320 		 * just truncate back to after the status.  But it's a
4321 		 * bug if we had to do this on a non-idempotent op:
4322 		 */
4323 		warn_on_nonidempotent_op(op);
4324 		xdr_truncate_encode(xdr, post_err_offset);
4325 	}
4326 	if (so) {
4327 		int len = xdr->buf->len - post_err_offset;
4328 
4329 		so->so_replay.rp_status = op->status;
4330 		so->so_replay.rp_buflen = len;
4331 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
4332 						so->so_replay.rp_buf, len);
4333 	}
4334 status:
4335 	/* Note that op->status is already in network byte order: */
4336 	write_bytes_to_xdr_buf(xdr->buf, post_err_offset - 4, &op->status, 4);
4337 }
4338 
4339 /*
4340  * Encode the reply stored in the stateowner reply cache
4341  *
4342  * XDR note: do not encode rp->rp_buflen: the buffer contains the
4343  * previously sent already encoded operation.
4344  */
4345 void
4346 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
4347 {
4348 	__be32 *p;
4349 	struct nfs4_replay *rp = op->replay;
4350 
4351 	BUG_ON(!rp);
4352 
4353 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
4354 	if (!p) {
4355 		WARN_ON_ONCE(1);
4356 		return;
4357 	}
4358 	*p++ = cpu_to_be32(op->opnum);
4359 	*p++ = rp->rp_status;  /* already xdr'ed */
4360 
4361 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
4362 }
4363 
4364 int
4365 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
4366 {
4367         return xdr_ressize_check(rqstp, p);
4368 }
4369 
4370 int nfsd4_release_compoundargs(void *rq, __be32 *p, void *resp)
4371 {
4372 	struct svc_rqst *rqstp = rq;
4373 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4374 
4375 	if (args->ops != args->iops) {
4376 		kfree(args->ops);
4377 		args->ops = args->iops;
4378 	}
4379 	kfree(args->tmpp);
4380 	args->tmpp = NULL;
4381 	while (args->to_free) {
4382 		struct svcxdr_tmpbuf *tb = args->to_free;
4383 		args->to_free = tb->next;
4384 		kfree(tb);
4385 	}
4386 	return 1;
4387 }
4388 
4389 int
4390 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundargs *args)
4391 {
4392 	if (rqstp->rq_arg.head[0].iov_len % 4) {
4393 		/* client is nuts */
4394 		dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)",
4395 			__func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid));
4396 		return 0;
4397 	}
4398 	args->p = p;
4399 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
4400 	args->pagelist = rqstp->rq_arg.pages;
4401 	args->pagelen = rqstp->rq_arg.page_len;
4402 	args->tmpp = NULL;
4403 	args->to_free = NULL;
4404 	args->ops = args->iops;
4405 	args->rqstp = rqstp;
4406 
4407 	return !nfsd4_decode_compound(args);
4408 }
4409 
4410 int
4411 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundres *resp)
4412 {
4413 	/*
4414 	 * All that remains is to write the tag and operation count...
4415 	 */
4416 	struct xdr_buf *buf = resp->xdr.buf;
4417 
4418 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
4419 				 buf->tail[0].iov_len);
4420 
4421 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
4422 
4423 	p = resp->tagp;
4424 	*p++ = htonl(resp->taglen);
4425 	memcpy(p, resp->tag, resp->taglen);
4426 	p += XDR_QUADLEN(resp->taglen);
4427 	*p++ = htonl(resp->opcnt);
4428 
4429 	nfsd4_sequence_done(resp);
4430 	return 1;
4431 }
4432 
4433 /*
4434  * Local variables:
4435  *  c-basic-offset: 8
4436  * End:
4437  */
4438