xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision cd4d09ec)
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/file.h>
37 #include <linux/slab.h>
38 #include <linux/namei.h>
39 #include <linux/statfs.h>
40 #include <linux/utsname.h>
41 #include <linux/pagemap.h>
42 #include <linux/sunrpc/svcauth_gss.h>
43 
44 #include "idmap.h"
45 #include "acl.h"
46 #include "xdr4.h"
47 #include "vfs.h"
48 #include "state.h"
49 #include "cache.h"
50 #include "netns.h"
51 #include "pnfs.h"
52 
53 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
54 #include <linux/security.h>
55 #endif
56 
57 
58 #define NFSDDBG_FACILITY		NFSDDBG_XDR
59 
60 /*
61  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
62  * directory in order to indicate to the client that a filesystem boundary is present
63  * We use a fixed fsid for a referral
64  */
65 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
66 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
67 
68 static __be32
69 check_filename(char *str, int len)
70 {
71 	int i;
72 
73 	if (len == 0)
74 		return nfserr_inval;
75 	if (isdotent(str, len))
76 		return nfserr_badname;
77 	for (i = 0; i < len; i++)
78 		if (str[i] == '/')
79 			return nfserr_badname;
80 	return 0;
81 }
82 
83 #define DECODE_HEAD				\
84 	__be32 *p;				\
85 	__be32 status
86 #define DECODE_TAIL				\
87 	status = 0;				\
88 out:						\
89 	return status;				\
90 xdr_error:					\
91 	dprintk("NFSD: xdr error (%s:%d)\n",	\
92 			__FILE__, __LINE__);	\
93 	status = nfserr_bad_xdr;		\
94 	goto out
95 
96 #define READMEM(x,nbytes) do {			\
97 	x = (char *)p;				\
98 	p += XDR_QUADLEN(nbytes);		\
99 } while (0)
100 #define SAVEMEM(x,nbytes) do {			\
101 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
102  		savemem(argp, p, nbytes) :	\
103  		(char *)p)) {			\
104 		dprintk("NFSD: xdr error (%s:%d)\n", \
105 				__FILE__, __LINE__); \
106 		goto xdr_error;			\
107 		}				\
108 	p += XDR_QUADLEN(nbytes);		\
109 } while (0)
110 #define COPYMEM(x,nbytes) do {			\
111 	memcpy((x), p, nbytes);			\
112 	p += XDR_QUADLEN(nbytes);		\
113 } while (0)
114 
115 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
116 #define READ_BUF(nbytes)  do {			\
117 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
118 		p = argp->p;			\
119 		argp->p += XDR_QUADLEN(nbytes);	\
120 	} else if (!(p = read_buf(argp, nbytes))) { \
121 		dprintk("NFSD: xdr error (%s:%d)\n", \
122 				__FILE__, __LINE__); \
123 		goto xdr_error;			\
124 	}					\
125 } while (0)
126 
127 static void next_decode_page(struct nfsd4_compoundargs *argp)
128 {
129 	argp->p = page_address(argp->pagelist[0]);
130 	argp->pagelist++;
131 	if (argp->pagelen < PAGE_SIZE) {
132 		argp->end = argp->p + (argp->pagelen>>2);
133 		argp->pagelen = 0;
134 	} else {
135 		argp->end = argp->p + (PAGE_SIZE>>2);
136 		argp->pagelen -= PAGE_SIZE;
137 	}
138 }
139 
140 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
141 {
142 	/* We want more bytes than seem to be available.
143 	 * Maybe we need a new page, maybe we have just run out
144 	 */
145 	unsigned int avail = (char *)argp->end - (char *)argp->p;
146 	__be32 *p;
147 	if (avail + argp->pagelen < nbytes)
148 		return NULL;
149 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
150 		return NULL;
151 	/* ok, we can do it with the current plus the next page */
152 	if (nbytes <= sizeof(argp->tmp))
153 		p = argp->tmp;
154 	else {
155 		kfree(argp->tmpp);
156 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
157 		if (!p)
158 			return NULL;
159 
160 	}
161 	/*
162 	 * The following memcpy is safe because read_buf is always
163 	 * called with nbytes > avail, and the two cases above both
164 	 * guarantee p points to at least nbytes bytes.
165 	 */
166 	memcpy(p, argp->p, avail);
167 	next_decode_page(argp);
168 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
169 	argp->p += XDR_QUADLEN(nbytes - avail);
170 	return p;
171 }
172 
173 static int zero_clientid(clientid_t *clid)
174 {
175 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
176 }
177 
178 /**
179  * svcxdr_tmpalloc - allocate memory to be freed after compound processing
180  * @argp: NFSv4 compound argument structure
181  * @p: pointer to be freed (with kfree())
182  *
183  * Marks @p to be freed when processing the compound operation
184  * described in @argp finishes.
185  */
186 static void *
187 svcxdr_tmpalloc(struct nfsd4_compoundargs *argp, u32 len)
188 {
189 	struct svcxdr_tmpbuf *tb;
190 
191 	tb = kmalloc(sizeof(*tb) + len, GFP_KERNEL);
192 	if (!tb)
193 		return NULL;
194 	tb->next = argp->to_free;
195 	argp->to_free = tb;
196 	return tb->buf;
197 }
198 
199 /*
200  * For xdr strings that need to be passed to other kernel api's
201  * as null-terminated strings.
202  *
203  * Note null-terminating in place usually isn't safe since the
204  * buffer might end on a page boundary.
205  */
206 static char *
207 svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len)
208 {
209 	char *p = svcxdr_tmpalloc(argp, len + 1);
210 
211 	if (!p)
212 		return NULL;
213 	memcpy(p, buf, len);
214 	p[len] = '\0';
215 	return p;
216 }
217 
218 /**
219  * savemem - duplicate a chunk of memory for later processing
220  * @argp: NFSv4 compound argument structure to be freed with
221  * @p: pointer to be duplicated
222  * @nbytes: length to be duplicated
223  *
224  * Returns a pointer to a copy of @nbytes bytes of memory at @p
225  * that are preserved until processing of the NFSv4 compound
226  * operation described by @argp finishes.
227  */
228 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
229 {
230 	void *ret;
231 
232 	ret = svcxdr_tmpalloc(argp, nbytes);
233 	if (!ret)
234 		return NULL;
235 	memcpy(ret, p, nbytes);
236 	return ret;
237 }
238 
239 /*
240  * We require the high 32 bits of 'seconds' to be 0, and
241  * we ignore all 32 bits of 'nseconds'.
242  */
243 static __be32
244 nfsd4_decode_time(struct nfsd4_compoundargs *argp, struct timespec *tv)
245 {
246 	DECODE_HEAD;
247 	u64 sec;
248 
249 	READ_BUF(12);
250 	p = xdr_decode_hyper(p, &sec);
251 	tv->tv_sec = sec;
252 	tv->tv_nsec = be32_to_cpup(p++);
253 	if (tv->tv_nsec >= (u32)1000000000)
254 		return nfserr_inval;
255 
256 	DECODE_TAIL;
257 }
258 
259 static __be32
260 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
261 {
262 	u32 bmlen;
263 	DECODE_HEAD;
264 
265 	bmval[0] = 0;
266 	bmval[1] = 0;
267 	bmval[2] = 0;
268 
269 	READ_BUF(4);
270 	bmlen = be32_to_cpup(p++);
271 	if (bmlen > 1000)
272 		goto xdr_error;
273 
274 	READ_BUF(bmlen << 2);
275 	if (bmlen > 0)
276 		bmval[0] = be32_to_cpup(p++);
277 	if (bmlen > 1)
278 		bmval[1] = be32_to_cpup(p++);
279 	if (bmlen > 2)
280 		bmval[2] = be32_to_cpup(p++);
281 
282 	DECODE_TAIL;
283 }
284 
285 static __be32
286 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
287 		   struct iattr *iattr, struct nfs4_acl **acl,
288 		   struct xdr_netobj *label)
289 {
290 	int expected_len, len = 0;
291 	u32 dummy32;
292 	char *buf;
293 
294 	DECODE_HEAD;
295 	iattr->ia_valid = 0;
296 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
297 		return status;
298 
299 	READ_BUF(4);
300 	expected_len = be32_to_cpup(p++);
301 
302 	if (bmval[0] & FATTR4_WORD0_SIZE) {
303 		READ_BUF(8);
304 		len += 8;
305 		p = xdr_decode_hyper(p, &iattr->ia_size);
306 		iattr->ia_valid |= ATTR_SIZE;
307 	}
308 	if (bmval[0] & FATTR4_WORD0_ACL) {
309 		u32 nace;
310 		struct nfs4_ace *ace;
311 
312 		READ_BUF(4); len += 4;
313 		nace = be32_to_cpup(p++);
314 
315 		if (nace > NFS4_ACL_MAX)
316 			return nfserr_fbig;
317 
318 		*acl = svcxdr_tmpalloc(argp, nfs4_acl_bytes(nace));
319 		if (*acl == NULL)
320 			return nfserr_jukebox;
321 
322 		(*acl)->naces = nace;
323 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
324 			READ_BUF(16); len += 16;
325 			ace->type = be32_to_cpup(p++);
326 			ace->flag = be32_to_cpup(p++);
327 			ace->access_mask = be32_to_cpup(p++);
328 			dummy32 = be32_to_cpup(p++);
329 			READ_BUF(dummy32);
330 			len += XDR_QUADLEN(dummy32) << 2;
331 			READMEM(buf, dummy32);
332 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
333 			status = nfs_ok;
334 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
335 				;
336 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
337 				status = nfsd_map_name_to_gid(argp->rqstp,
338 						buf, dummy32, &ace->who_gid);
339 			else
340 				status = nfsd_map_name_to_uid(argp->rqstp,
341 						buf, dummy32, &ace->who_uid);
342 			if (status)
343 				return status;
344 		}
345 	} else
346 		*acl = NULL;
347 	if (bmval[1] & FATTR4_WORD1_MODE) {
348 		READ_BUF(4);
349 		len += 4;
350 		iattr->ia_mode = be32_to_cpup(p++);
351 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
352 		iattr->ia_valid |= ATTR_MODE;
353 	}
354 	if (bmval[1] & FATTR4_WORD1_OWNER) {
355 		READ_BUF(4);
356 		len += 4;
357 		dummy32 = be32_to_cpup(p++);
358 		READ_BUF(dummy32);
359 		len += (XDR_QUADLEN(dummy32) << 2);
360 		READMEM(buf, dummy32);
361 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
362 			return status;
363 		iattr->ia_valid |= ATTR_UID;
364 	}
365 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
366 		READ_BUF(4);
367 		len += 4;
368 		dummy32 = be32_to_cpup(p++);
369 		READ_BUF(dummy32);
370 		len += (XDR_QUADLEN(dummy32) << 2);
371 		READMEM(buf, dummy32);
372 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
373 			return status;
374 		iattr->ia_valid |= ATTR_GID;
375 	}
376 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
377 		READ_BUF(4);
378 		len += 4;
379 		dummy32 = be32_to_cpup(p++);
380 		switch (dummy32) {
381 		case NFS4_SET_TO_CLIENT_TIME:
382 			len += 12;
383 			status = nfsd4_decode_time(argp, &iattr->ia_atime);
384 			if (status)
385 				return status;
386 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
387 			break;
388 		case NFS4_SET_TO_SERVER_TIME:
389 			iattr->ia_valid |= ATTR_ATIME;
390 			break;
391 		default:
392 			goto xdr_error;
393 		}
394 	}
395 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
396 		READ_BUF(4);
397 		len += 4;
398 		dummy32 = be32_to_cpup(p++);
399 		switch (dummy32) {
400 		case NFS4_SET_TO_CLIENT_TIME:
401 			len += 12;
402 			status = nfsd4_decode_time(argp, &iattr->ia_mtime);
403 			if (status)
404 				return status;
405 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
406 			break;
407 		case NFS4_SET_TO_SERVER_TIME:
408 			iattr->ia_valid |= ATTR_MTIME;
409 			break;
410 		default:
411 			goto xdr_error;
412 		}
413 	}
414 
415 	label->len = 0;
416 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
417 	if (bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
418 		READ_BUF(4);
419 		len += 4;
420 		dummy32 = be32_to_cpup(p++); /* lfs: we don't use it */
421 		READ_BUF(4);
422 		len += 4;
423 		dummy32 = be32_to_cpup(p++); /* pi: we don't use it either */
424 		READ_BUF(4);
425 		len += 4;
426 		dummy32 = be32_to_cpup(p++);
427 		READ_BUF(dummy32);
428 		if (dummy32 > NFS4_MAXLABELLEN)
429 			return nfserr_badlabel;
430 		len += (XDR_QUADLEN(dummy32) << 2);
431 		READMEM(buf, dummy32);
432 		label->len = dummy32;
433 		label->data = svcxdr_dupstr(argp, buf, dummy32);
434 		if (!label->data)
435 			return nfserr_jukebox;
436 	}
437 #endif
438 
439 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
440 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
441 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2)
442 		READ_BUF(expected_len - len);
443 	else if (len != expected_len)
444 		goto xdr_error;
445 
446 	DECODE_TAIL;
447 }
448 
449 static __be32
450 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
451 {
452 	DECODE_HEAD;
453 
454 	READ_BUF(sizeof(stateid_t));
455 	sid->si_generation = be32_to_cpup(p++);
456 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
457 
458 	DECODE_TAIL;
459 }
460 
461 static __be32
462 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
463 {
464 	DECODE_HEAD;
465 
466 	READ_BUF(4);
467 	access->ac_req_access = be32_to_cpup(p++);
468 
469 	DECODE_TAIL;
470 }
471 
472 static __be32 nfsd4_decode_cb_sec(struct nfsd4_compoundargs *argp, struct nfsd4_cb_sec *cbs)
473 {
474 	DECODE_HEAD;
475 	u32 dummy, uid, gid;
476 	char *machine_name;
477 	int i;
478 	int nr_secflavs;
479 
480 	/* callback_sec_params4 */
481 	READ_BUF(4);
482 	nr_secflavs = be32_to_cpup(p++);
483 	if (nr_secflavs)
484 		cbs->flavor = (u32)(-1);
485 	else
486 		/* Is this legal? Be generous, take it to mean AUTH_NONE: */
487 		cbs->flavor = 0;
488 	for (i = 0; i < nr_secflavs; ++i) {
489 		READ_BUF(4);
490 		dummy = be32_to_cpup(p++);
491 		switch (dummy) {
492 		case RPC_AUTH_NULL:
493 			/* Nothing to read */
494 			if (cbs->flavor == (u32)(-1))
495 				cbs->flavor = RPC_AUTH_NULL;
496 			break;
497 		case RPC_AUTH_UNIX:
498 			READ_BUF(8);
499 			/* stamp */
500 			dummy = be32_to_cpup(p++);
501 
502 			/* machine name */
503 			dummy = be32_to_cpup(p++);
504 			READ_BUF(dummy);
505 			SAVEMEM(machine_name, dummy);
506 
507 			/* uid, gid */
508 			READ_BUF(8);
509 			uid = be32_to_cpup(p++);
510 			gid = be32_to_cpup(p++);
511 
512 			/* more gids */
513 			READ_BUF(4);
514 			dummy = be32_to_cpup(p++);
515 			READ_BUF(dummy * 4);
516 			if (cbs->flavor == (u32)(-1)) {
517 				kuid_t kuid = make_kuid(&init_user_ns, uid);
518 				kgid_t kgid = make_kgid(&init_user_ns, gid);
519 				if (uid_valid(kuid) && gid_valid(kgid)) {
520 					cbs->uid = kuid;
521 					cbs->gid = kgid;
522 					cbs->flavor = RPC_AUTH_UNIX;
523 				} else {
524 					dprintk("RPC_AUTH_UNIX with invalid"
525 						"uid or gid ignoring!\n");
526 				}
527 			}
528 			break;
529 		case RPC_AUTH_GSS:
530 			dprintk("RPC_AUTH_GSS callback secflavor "
531 				"not supported!\n");
532 			READ_BUF(8);
533 			/* gcbp_service */
534 			dummy = be32_to_cpup(p++);
535 			/* gcbp_handle_from_server */
536 			dummy = be32_to_cpup(p++);
537 			READ_BUF(dummy);
538 			p += XDR_QUADLEN(dummy);
539 			/* gcbp_handle_from_client */
540 			READ_BUF(4);
541 			dummy = be32_to_cpup(p++);
542 			READ_BUF(dummy);
543 			break;
544 		default:
545 			dprintk("Illegal callback secflavor\n");
546 			return nfserr_inval;
547 		}
548 	}
549 	DECODE_TAIL;
550 }
551 
552 static __be32 nfsd4_decode_backchannel_ctl(struct nfsd4_compoundargs *argp, struct nfsd4_backchannel_ctl *bc)
553 {
554 	DECODE_HEAD;
555 
556 	READ_BUF(4);
557 	bc->bc_cb_program = be32_to_cpup(p++);
558 	nfsd4_decode_cb_sec(argp, &bc->bc_cb_sec);
559 
560 	DECODE_TAIL;
561 }
562 
563 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
564 {
565 	DECODE_HEAD;
566 
567 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
568 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
569 	bcts->dir = be32_to_cpup(p++);
570 	/* XXX: skipping ctsa_use_conn_in_rdma_mode.  Perhaps Tom Tucker
571 	 * could help us figure out we should be using it. */
572 	DECODE_TAIL;
573 }
574 
575 static __be32
576 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
577 {
578 	DECODE_HEAD;
579 
580 	READ_BUF(4);
581 	close->cl_seqid = be32_to_cpup(p++);
582 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
583 
584 	DECODE_TAIL;
585 }
586 
587 
588 static __be32
589 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
590 {
591 	DECODE_HEAD;
592 
593 	READ_BUF(12);
594 	p = xdr_decode_hyper(p, &commit->co_offset);
595 	commit->co_count = be32_to_cpup(p++);
596 
597 	DECODE_TAIL;
598 }
599 
600 static __be32
601 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
602 {
603 	DECODE_HEAD;
604 
605 	READ_BUF(4);
606 	create->cr_type = be32_to_cpup(p++);
607 	switch (create->cr_type) {
608 	case NF4LNK:
609 		READ_BUF(4);
610 		create->cr_datalen = be32_to_cpup(p++);
611 		READ_BUF(create->cr_datalen);
612 		create->cr_data = svcxdr_dupstr(argp, p, create->cr_datalen);
613 		if (!create->cr_data)
614 			return nfserr_jukebox;
615 		break;
616 	case NF4BLK:
617 	case NF4CHR:
618 		READ_BUF(8);
619 		create->cr_specdata1 = be32_to_cpup(p++);
620 		create->cr_specdata2 = be32_to_cpup(p++);
621 		break;
622 	case NF4SOCK:
623 	case NF4FIFO:
624 	case NF4DIR:
625 	default:
626 		break;
627 	}
628 
629 	READ_BUF(4);
630 	create->cr_namelen = be32_to_cpup(p++);
631 	READ_BUF(create->cr_namelen);
632 	SAVEMEM(create->cr_name, create->cr_namelen);
633 	if ((status = check_filename(create->cr_name, create->cr_namelen)))
634 		return status;
635 
636 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
637 				    &create->cr_acl, &create->cr_label);
638 	if (status)
639 		goto out;
640 
641 	DECODE_TAIL;
642 }
643 
644 static inline __be32
645 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
646 {
647 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
648 }
649 
650 static inline __be32
651 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
652 {
653 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
654 }
655 
656 static __be32
657 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
658 {
659 	DECODE_HEAD;
660 
661 	READ_BUF(4);
662 	link->li_namelen = be32_to_cpup(p++);
663 	READ_BUF(link->li_namelen);
664 	SAVEMEM(link->li_name, link->li_namelen);
665 	if ((status = check_filename(link->li_name, link->li_namelen)))
666 		return status;
667 
668 	DECODE_TAIL;
669 }
670 
671 static __be32
672 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
673 {
674 	DECODE_HEAD;
675 
676 	/*
677 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
678 	*/
679 	READ_BUF(28);
680 	lock->lk_type = be32_to_cpup(p++);
681 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
682 		goto xdr_error;
683 	lock->lk_reclaim = be32_to_cpup(p++);
684 	p = xdr_decode_hyper(p, &lock->lk_offset);
685 	p = xdr_decode_hyper(p, &lock->lk_length);
686 	lock->lk_is_new = be32_to_cpup(p++);
687 
688 	if (lock->lk_is_new) {
689 		READ_BUF(4);
690 		lock->lk_new_open_seqid = be32_to_cpup(p++);
691 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
692 		if (status)
693 			return status;
694 		READ_BUF(8 + sizeof(clientid_t));
695 		lock->lk_new_lock_seqid = be32_to_cpup(p++);
696 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
697 		lock->lk_new_owner.len = be32_to_cpup(p++);
698 		READ_BUF(lock->lk_new_owner.len);
699 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
700 	} else {
701 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
702 		if (status)
703 			return status;
704 		READ_BUF(4);
705 		lock->lk_old_lock_seqid = be32_to_cpup(p++);
706 	}
707 
708 	DECODE_TAIL;
709 }
710 
711 static __be32
712 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
713 {
714 	DECODE_HEAD;
715 
716 	READ_BUF(32);
717 	lockt->lt_type = be32_to_cpup(p++);
718 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
719 		goto xdr_error;
720 	p = xdr_decode_hyper(p, &lockt->lt_offset);
721 	p = xdr_decode_hyper(p, &lockt->lt_length);
722 	COPYMEM(&lockt->lt_clientid, 8);
723 	lockt->lt_owner.len = be32_to_cpup(p++);
724 	READ_BUF(lockt->lt_owner.len);
725 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
726 
727 	DECODE_TAIL;
728 }
729 
730 static __be32
731 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
732 {
733 	DECODE_HEAD;
734 
735 	READ_BUF(8);
736 	locku->lu_type = be32_to_cpup(p++);
737 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
738 		goto xdr_error;
739 	locku->lu_seqid = be32_to_cpup(p++);
740 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
741 	if (status)
742 		return status;
743 	READ_BUF(16);
744 	p = xdr_decode_hyper(p, &locku->lu_offset);
745 	p = xdr_decode_hyper(p, &locku->lu_length);
746 
747 	DECODE_TAIL;
748 }
749 
750 static __be32
751 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
752 {
753 	DECODE_HEAD;
754 
755 	READ_BUF(4);
756 	lookup->lo_len = be32_to_cpup(p++);
757 	READ_BUF(lookup->lo_len);
758 	SAVEMEM(lookup->lo_name, lookup->lo_len);
759 	if ((status = check_filename(lookup->lo_name, lookup->lo_len)))
760 		return status;
761 
762 	DECODE_TAIL;
763 }
764 
765 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
766 {
767 	__be32 *p;
768 	u32 w;
769 
770 	READ_BUF(4);
771 	w = be32_to_cpup(p++);
772 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
773 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
774 	if (deleg_when)
775 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
776 
777 	switch (w & NFS4_SHARE_ACCESS_MASK) {
778 	case NFS4_SHARE_ACCESS_READ:
779 	case NFS4_SHARE_ACCESS_WRITE:
780 	case NFS4_SHARE_ACCESS_BOTH:
781 		break;
782 	default:
783 		return nfserr_bad_xdr;
784 	}
785 	w &= ~NFS4_SHARE_ACCESS_MASK;
786 	if (!w)
787 		return nfs_ok;
788 	if (!argp->minorversion)
789 		return nfserr_bad_xdr;
790 	switch (w & NFS4_SHARE_WANT_MASK) {
791 	case NFS4_SHARE_WANT_NO_PREFERENCE:
792 	case NFS4_SHARE_WANT_READ_DELEG:
793 	case NFS4_SHARE_WANT_WRITE_DELEG:
794 	case NFS4_SHARE_WANT_ANY_DELEG:
795 	case NFS4_SHARE_WANT_NO_DELEG:
796 	case NFS4_SHARE_WANT_CANCEL:
797 		break;
798 	default:
799 		return nfserr_bad_xdr;
800 	}
801 	w &= ~NFS4_SHARE_WANT_MASK;
802 	if (!w)
803 		return nfs_ok;
804 
805 	if (!deleg_when)	/* open_downgrade */
806 		return nfserr_inval;
807 	switch (w) {
808 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
809 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
810 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
811 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
812 		return nfs_ok;
813 	}
814 xdr_error:
815 	return nfserr_bad_xdr;
816 }
817 
818 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
819 {
820 	__be32 *p;
821 
822 	READ_BUF(4);
823 	*x = be32_to_cpup(p++);
824 	/* Note: unlinke access bits, deny bits may be zero. */
825 	if (*x & ~NFS4_SHARE_DENY_BOTH)
826 		return nfserr_bad_xdr;
827 	return nfs_ok;
828 xdr_error:
829 	return nfserr_bad_xdr;
830 }
831 
832 static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
833 {
834 	__be32 *p;
835 
836 	READ_BUF(4);
837 	o->len = be32_to_cpup(p++);
838 
839 	if (o->len == 0 || o->len > NFS4_OPAQUE_LIMIT)
840 		return nfserr_bad_xdr;
841 
842 	READ_BUF(o->len);
843 	SAVEMEM(o->data, o->len);
844 	return nfs_ok;
845 xdr_error:
846 	return nfserr_bad_xdr;
847 }
848 
849 static __be32
850 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
851 {
852 	DECODE_HEAD;
853 	u32 dummy;
854 
855 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
856 	open->op_iattr.ia_valid = 0;
857 	open->op_openowner = NULL;
858 
859 	open->op_xdr_error = 0;
860 	/* seqid, share_access, share_deny, clientid, ownerlen */
861 	READ_BUF(4);
862 	open->op_seqid = be32_to_cpup(p++);
863 	/* decode, yet ignore deleg_when until supported */
864 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
865 					   &open->op_deleg_want, &dummy);
866 	if (status)
867 		goto xdr_error;
868 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
869 	if (status)
870 		goto xdr_error;
871 	READ_BUF(sizeof(clientid_t));
872 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
873 	status = nfsd4_decode_opaque(argp, &open->op_owner);
874 	if (status)
875 		goto xdr_error;
876 	READ_BUF(4);
877 	open->op_create = be32_to_cpup(p++);
878 	switch (open->op_create) {
879 	case NFS4_OPEN_NOCREATE:
880 		break;
881 	case NFS4_OPEN_CREATE:
882 		READ_BUF(4);
883 		open->op_createmode = be32_to_cpup(p++);
884 		switch (open->op_createmode) {
885 		case NFS4_CREATE_UNCHECKED:
886 		case NFS4_CREATE_GUARDED:
887 			status = nfsd4_decode_fattr(argp, open->op_bmval,
888 				&open->op_iattr, &open->op_acl, &open->op_label);
889 			if (status)
890 				goto out;
891 			break;
892 		case NFS4_CREATE_EXCLUSIVE:
893 			READ_BUF(NFS4_VERIFIER_SIZE);
894 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
895 			break;
896 		case NFS4_CREATE_EXCLUSIVE4_1:
897 			if (argp->minorversion < 1)
898 				goto xdr_error;
899 			READ_BUF(NFS4_VERIFIER_SIZE);
900 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
901 			status = nfsd4_decode_fattr(argp, open->op_bmval,
902 				&open->op_iattr, &open->op_acl, &open->op_label);
903 			if (status)
904 				goto out;
905 			break;
906 		default:
907 			goto xdr_error;
908 		}
909 		break;
910 	default:
911 		goto xdr_error;
912 	}
913 
914 	/* open_claim */
915 	READ_BUF(4);
916 	open->op_claim_type = be32_to_cpup(p++);
917 	switch (open->op_claim_type) {
918 	case NFS4_OPEN_CLAIM_NULL:
919 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
920 		READ_BUF(4);
921 		open->op_fname.len = be32_to_cpup(p++);
922 		READ_BUF(open->op_fname.len);
923 		SAVEMEM(open->op_fname.data, open->op_fname.len);
924 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
925 			return status;
926 		break;
927 	case NFS4_OPEN_CLAIM_PREVIOUS:
928 		READ_BUF(4);
929 		open->op_delegate_type = be32_to_cpup(p++);
930 		break;
931 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
932 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
933 		if (status)
934 			return status;
935 		READ_BUF(4);
936 		open->op_fname.len = be32_to_cpup(p++);
937 		READ_BUF(open->op_fname.len);
938 		SAVEMEM(open->op_fname.data, open->op_fname.len);
939 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
940 			return status;
941 		break;
942 	case NFS4_OPEN_CLAIM_FH:
943 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
944 		if (argp->minorversion < 1)
945 			goto xdr_error;
946 		/* void */
947 		break;
948 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
949 		if (argp->minorversion < 1)
950 			goto xdr_error;
951 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
952 		if (status)
953 			return status;
954 		break;
955 	default:
956 		goto xdr_error;
957 	}
958 
959 	DECODE_TAIL;
960 }
961 
962 static __be32
963 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
964 {
965 	DECODE_HEAD;
966 
967 	if (argp->minorversion >= 1)
968 		return nfserr_notsupp;
969 
970 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
971 	if (status)
972 		return status;
973 	READ_BUF(4);
974 	open_conf->oc_seqid = be32_to_cpup(p++);
975 
976 	DECODE_TAIL;
977 }
978 
979 static __be32
980 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
981 {
982 	DECODE_HEAD;
983 
984 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
985 	if (status)
986 		return status;
987 	READ_BUF(4);
988 	open_down->od_seqid = be32_to_cpup(p++);
989 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
990 					   &open_down->od_deleg_want, NULL);
991 	if (status)
992 		return status;
993 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
994 	if (status)
995 		return status;
996 	DECODE_TAIL;
997 }
998 
999 static __be32
1000 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
1001 {
1002 	DECODE_HEAD;
1003 
1004 	READ_BUF(4);
1005 	putfh->pf_fhlen = be32_to_cpup(p++);
1006 	if (putfh->pf_fhlen > NFS4_FHSIZE)
1007 		goto xdr_error;
1008 	READ_BUF(putfh->pf_fhlen);
1009 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
1010 
1011 	DECODE_TAIL;
1012 }
1013 
1014 static __be32
1015 nfsd4_decode_putpubfh(struct nfsd4_compoundargs *argp, void *p)
1016 {
1017 	if (argp->minorversion == 0)
1018 		return nfs_ok;
1019 	return nfserr_notsupp;
1020 }
1021 
1022 static __be32
1023 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
1024 {
1025 	DECODE_HEAD;
1026 
1027 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
1028 	if (status)
1029 		return status;
1030 	READ_BUF(12);
1031 	p = xdr_decode_hyper(p, &read->rd_offset);
1032 	read->rd_length = be32_to_cpup(p++);
1033 
1034 	DECODE_TAIL;
1035 }
1036 
1037 static __be32
1038 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
1039 {
1040 	DECODE_HEAD;
1041 
1042 	READ_BUF(24);
1043 	p = xdr_decode_hyper(p, &readdir->rd_cookie);
1044 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
1045 	readdir->rd_dircount = be32_to_cpup(p++);
1046 	readdir->rd_maxcount = be32_to_cpup(p++);
1047 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
1048 		goto out;
1049 
1050 	DECODE_TAIL;
1051 }
1052 
1053 static __be32
1054 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
1055 {
1056 	DECODE_HEAD;
1057 
1058 	READ_BUF(4);
1059 	remove->rm_namelen = be32_to_cpup(p++);
1060 	READ_BUF(remove->rm_namelen);
1061 	SAVEMEM(remove->rm_name, remove->rm_namelen);
1062 	if ((status = check_filename(remove->rm_name, remove->rm_namelen)))
1063 		return status;
1064 
1065 	DECODE_TAIL;
1066 }
1067 
1068 static __be32
1069 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
1070 {
1071 	DECODE_HEAD;
1072 
1073 	READ_BUF(4);
1074 	rename->rn_snamelen = be32_to_cpup(p++);
1075 	READ_BUF(rename->rn_snamelen + 4);
1076 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1077 	rename->rn_tnamelen = be32_to_cpup(p++);
1078 	READ_BUF(rename->rn_tnamelen);
1079 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1080 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1081 		return status;
1082 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1083 		return status;
1084 
1085 	DECODE_TAIL;
1086 }
1087 
1088 static __be32
1089 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1090 {
1091 	DECODE_HEAD;
1092 
1093 	if (argp->minorversion >= 1)
1094 		return nfserr_notsupp;
1095 
1096 	READ_BUF(sizeof(clientid_t));
1097 	COPYMEM(clientid, sizeof(clientid_t));
1098 
1099 	DECODE_TAIL;
1100 }
1101 
1102 static __be32
1103 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1104 		     struct nfsd4_secinfo *secinfo)
1105 {
1106 	DECODE_HEAD;
1107 
1108 	READ_BUF(4);
1109 	secinfo->si_namelen = be32_to_cpup(p++);
1110 	READ_BUF(secinfo->si_namelen);
1111 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1112 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1113 	if (status)
1114 		return status;
1115 	DECODE_TAIL;
1116 }
1117 
1118 static __be32
1119 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1120 		     struct nfsd4_secinfo_no_name *sin)
1121 {
1122 	DECODE_HEAD;
1123 
1124 	READ_BUF(4);
1125 	sin->sin_style = be32_to_cpup(p++);
1126 	DECODE_TAIL;
1127 }
1128 
1129 static __be32
1130 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1131 {
1132 	__be32 status;
1133 
1134 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1135 	if (status)
1136 		return status;
1137 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1138 				  &setattr->sa_acl, &setattr->sa_label);
1139 }
1140 
1141 static __be32
1142 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1143 {
1144 	DECODE_HEAD;
1145 
1146 	if (argp->minorversion >= 1)
1147 		return nfserr_notsupp;
1148 
1149 	READ_BUF(NFS4_VERIFIER_SIZE);
1150 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1151 
1152 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1153 	if (status)
1154 		return nfserr_bad_xdr;
1155 	READ_BUF(8);
1156 	setclientid->se_callback_prog = be32_to_cpup(p++);
1157 	setclientid->se_callback_netid_len = be32_to_cpup(p++);
1158 
1159 	READ_BUF(setclientid->se_callback_netid_len + 4);
1160 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1161 	setclientid->se_callback_addr_len = be32_to_cpup(p++);
1162 
1163 	READ_BUF(setclientid->se_callback_addr_len + 4);
1164 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1165 	setclientid->se_callback_ident = be32_to_cpup(p++);
1166 
1167 	DECODE_TAIL;
1168 }
1169 
1170 static __be32
1171 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1172 {
1173 	DECODE_HEAD;
1174 
1175 	if (argp->minorversion >= 1)
1176 		return nfserr_notsupp;
1177 
1178 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1179 	COPYMEM(&scd_c->sc_clientid, 8);
1180 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1181 
1182 	DECODE_TAIL;
1183 }
1184 
1185 /* Also used for NVERIFY */
1186 static __be32
1187 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1188 {
1189 	DECODE_HEAD;
1190 
1191 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1192 		goto out;
1193 
1194 	/* For convenience's sake, we compare raw xdr'd attributes in
1195 	 * nfsd4_proc_verify */
1196 
1197 	READ_BUF(4);
1198 	verify->ve_attrlen = be32_to_cpup(p++);
1199 	READ_BUF(verify->ve_attrlen);
1200 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1201 
1202 	DECODE_TAIL;
1203 }
1204 
1205 static __be32
1206 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1207 {
1208 	int avail;
1209 	int len;
1210 	DECODE_HEAD;
1211 
1212 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1213 	if (status)
1214 		return status;
1215 	READ_BUF(16);
1216 	p = xdr_decode_hyper(p, &write->wr_offset);
1217 	write->wr_stable_how = be32_to_cpup(p++);
1218 	if (write->wr_stable_how > 2)
1219 		goto xdr_error;
1220 	write->wr_buflen = be32_to_cpup(p++);
1221 
1222 	/* Sorry .. no magic macros for this.. *
1223 	 * READ_BUF(write->wr_buflen);
1224 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1225 	 */
1226 	avail = (char*)argp->end - (char*)argp->p;
1227 	if (avail + argp->pagelen < write->wr_buflen) {
1228 		dprintk("NFSD: xdr error (%s:%d)\n",
1229 				__FILE__, __LINE__);
1230 		goto xdr_error;
1231 	}
1232 	write->wr_head.iov_base = p;
1233 	write->wr_head.iov_len = avail;
1234 	write->wr_pagelist = argp->pagelist;
1235 
1236 	len = XDR_QUADLEN(write->wr_buflen) << 2;
1237 	if (len >= avail) {
1238 		int pages;
1239 
1240 		len -= avail;
1241 
1242 		pages = len >> PAGE_SHIFT;
1243 		argp->pagelist += pages;
1244 		argp->pagelen -= pages * PAGE_SIZE;
1245 		len -= pages * PAGE_SIZE;
1246 
1247 		argp->p = (__be32 *)page_address(argp->pagelist[0]);
1248 		argp->pagelist++;
1249 		argp->end = argp->p + XDR_QUADLEN(PAGE_SIZE);
1250 	}
1251 	argp->p += XDR_QUADLEN(len);
1252 
1253 	DECODE_TAIL;
1254 }
1255 
1256 static __be32
1257 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1258 {
1259 	DECODE_HEAD;
1260 
1261 	if (argp->minorversion >= 1)
1262 		return nfserr_notsupp;
1263 
1264 	READ_BUF(12);
1265 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1266 	rlockowner->rl_owner.len = be32_to_cpup(p++);
1267 	READ_BUF(rlockowner->rl_owner.len);
1268 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1269 
1270 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1271 		return nfserr_inval;
1272 	DECODE_TAIL;
1273 }
1274 
1275 static __be32
1276 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1277 			 struct nfsd4_exchange_id *exid)
1278 {
1279 	int dummy, tmp;
1280 	DECODE_HEAD;
1281 
1282 	READ_BUF(NFS4_VERIFIER_SIZE);
1283 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1284 
1285 	status = nfsd4_decode_opaque(argp, &exid->clname);
1286 	if (status)
1287 		return nfserr_bad_xdr;
1288 
1289 	READ_BUF(4);
1290 	exid->flags = be32_to_cpup(p++);
1291 
1292 	/* Ignore state_protect4_a */
1293 	READ_BUF(4);
1294 	exid->spa_how = be32_to_cpup(p++);
1295 	switch (exid->spa_how) {
1296 	case SP4_NONE:
1297 		break;
1298 	case SP4_MACH_CRED:
1299 		/* spo_must_enforce */
1300 		READ_BUF(4);
1301 		dummy = be32_to_cpup(p++);
1302 		READ_BUF(dummy * 4);
1303 		p += dummy;
1304 
1305 		/* spo_must_allow */
1306 		READ_BUF(4);
1307 		dummy = be32_to_cpup(p++);
1308 		READ_BUF(dummy * 4);
1309 		p += dummy;
1310 		break;
1311 	case SP4_SSV:
1312 		/* ssp_ops */
1313 		READ_BUF(4);
1314 		dummy = be32_to_cpup(p++);
1315 		READ_BUF(dummy * 4);
1316 		p += dummy;
1317 
1318 		READ_BUF(4);
1319 		dummy = be32_to_cpup(p++);
1320 		READ_BUF(dummy * 4);
1321 		p += dummy;
1322 
1323 		/* ssp_hash_algs<> */
1324 		READ_BUF(4);
1325 		tmp = be32_to_cpup(p++);
1326 		while (tmp--) {
1327 			READ_BUF(4);
1328 			dummy = be32_to_cpup(p++);
1329 			READ_BUF(dummy);
1330 			p += XDR_QUADLEN(dummy);
1331 		}
1332 
1333 		/* ssp_encr_algs<> */
1334 		READ_BUF(4);
1335 		tmp = be32_to_cpup(p++);
1336 		while (tmp--) {
1337 			READ_BUF(4);
1338 			dummy = be32_to_cpup(p++);
1339 			READ_BUF(dummy);
1340 			p += XDR_QUADLEN(dummy);
1341 		}
1342 
1343 		/* ssp_window and ssp_num_gss_handles */
1344 		READ_BUF(8);
1345 		dummy = be32_to_cpup(p++);
1346 		dummy = be32_to_cpup(p++);
1347 		break;
1348 	default:
1349 		goto xdr_error;
1350 	}
1351 
1352 	/* Ignore Implementation ID */
1353 	READ_BUF(4);    /* nfs_impl_id4 array length */
1354 	dummy = be32_to_cpup(p++);
1355 
1356 	if (dummy > 1)
1357 		goto xdr_error;
1358 
1359 	if (dummy == 1) {
1360 		/* nii_domain */
1361 		READ_BUF(4);
1362 		dummy = be32_to_cpup(p++);
1363 		READ_BUF(dummy);
1364 		p += XDR_QUADLEN(dummy);
1365 
1366 		/* nii_name */
1367 		READ_BUF(4);
1368 		dummy = be32_to_cpup(p++);
1369 		READ_BUF(dummy);
1370 		p += XDR_QUADLEN(dummy);
1371 
1372 		/* nii_date */
1373 		READ_BUF(12);
1374 		p += 3;
1375 	}
1376 	DECODE_TAIL;
1377 }
1378 
1379 static __be32
1380 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1381 			    struct nfsd4_create_session *sess)
1382 {
1383 	DECODE_HEAD;
1384 	u32 dummy;
1385 
1386 	READ_BUF(16);
1387 	COPYMEM(&sess->clientid, 8);
1388 	sess->seqid = be32_to_cpup(p++);
1389 	sess->flags = be32_to_cpup(p++);
1390 
1391 	/* Fore channel attrs */
1392 	READ_BUF(28);
1393 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1394 	sess->fore_channel.maxreq_sz = be32_to_cpup(p++);
1395 	sess->fore_channel.maxresp_sz = be32_to_cpup(p++);
1396 	sess->fore_channel.maxresp_cached = be32_to_cpup(p++);
1397 	sess->fore_channel.maxops = be32_to_cpup(p++);
1398 	sess->fore_channel.maxreqs = be32_to_cpup(p++);
1399 	sess->fore_channel.nr_rdma_attrs = be32_to_cpup(p++);
1400 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1401 		READ_BUF(4);
1402 		sess->fore_channel.rdma_attrs = be32_to_cpup(p++);
1403 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1404 		dprintk("Too many fore channel attr bitmaps!\n");
1405 		goto xdr_error;
1406 	}
1407 
1408 	/* Back channel attrs */
1409 	READ_BUF(28);
1410 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1411 	sess->back_channel.maxreq_sz = be32_to_cpup(p++);
1412 	sess->back_channel.maxresp_sz = be32_to_cpup(p++);
1413 	sess->back_channel.maxresp_cached = be32_to_cpup(p++);
1414 	sess->back_channel.maxops = be32_to_cpup(p++);
1415 	sess->back_channel.maxreqs = be32_to_cpup(p++);
1416 	sess->back_channel.nr_rdma_attrs = be32_to_cpup(p++);
1417 	if (sess->back_channel.nr_rdma_attrs == 1) {
1418 		READ_BUF(4);
1419 		sess->back_channel.rdma_attrs = be32_to_cpup(p++);
1420 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1421 		dprintk("Too many back channel attr bitmaps!\n");
1422 		goto xdr_error;
1423 	}
1424 
1425 	READ_BUF(4);
1426 	sess->callback_prog = be32_to_cpup(p++);
1427 	nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1428 	DECODE_TAIL;
1429 }
1430 
1431 static __be32
1432 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1433 			     struct nfsd4_destroy_session *destroy_session)
1434 {
1435 	DECODE_HEAD;
1436 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1437 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1438 
1439 	DECODE_TAIL;
1440 }
1441 
1442 static __be32
1443 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1444 			  struct nfsd4_free_stateid *free_stateid)
1445 {
1446 	DECODE_HEAD;
1447 
1448 	READ_BUF(sizeof(stateid_t));
1449 	free_stateid->fr_stateid.si_generation = be32_to_cpup(p++);
1450 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1451 
1452 	DECODE_TAIL;
1453 }
1454 
1455 static __be32
1456 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1457 		      struct nfsd4_sequence *seq)
1458 {
1459 	DECODE_HEAD;
1460 
1461 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1462 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1463 	seq->seqid = be32_to_cpup(p++);
1464 	seq->slotid = be32_to_cpup(p++);
1465 	seq->maxslots = be32_to_cpup(p++);
1466 	seq->cachethis = be32_to_cpup(p++);
1467 
1468 	DECODE_TAIL;
1469 }
1470 
1471 static __be32
1472 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1473 {
1474 	int i;
1475 	__be32 *p, status;
1476 	struct nfsd4_test_stateid_id *stateid;
1477 
1478 	READ_BUF(4);
1479 	test_stateid->ts_num_ids = ntohl(*p++);
1480 
1481 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1482 
1483 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1484 		stateid = svcxdr_tmpalloc(argp, sizeof(*stateid));
1485 		if (!stateid) {
1486 			status = nfserrno(-ENOMEM);
1487 			goto out;
1488 		}
1489 
1490 		INIT_LIST_HEAD(&stateid->ts_id_list);
1491 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1492 
1493 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1494 		if (status)
1495 			goto out;
1496 	}
1497 
1498 	status = 0;
1499 out:
1500 	return status;
1501 xdr_error:
1502 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1503 	status = nfserr_bad_xdr;
1504 	goto out;
1505 }
1506 
1507 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1508 {
1509 	DECODE_HEAD;
1510 
1511 	READ_BUF(8);
1512 	COPYMEM(&dc->clientid, 8);
1513 
1514 	DECODE_TAIL;
1515 }
1516 
1517 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1518 {
1519 	DECODE_HEAD;
1520 
1521 	READ_BUF(4);
1522 	rc->rca_one_fs = be32_to_cpup(p++);
1523 
1524 	DECODE_TAIL;
1525 }
1526 
1527 #ifdef CONFIG_NFSD_PNFS
1528 static __be32
1529 nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp,
1530 		struct nfsd4_getdeviceinfo *gdev)
1531 {
1532 	DECODE_HEAD;
1533 	u32 num, i;
1534 
1535 	READ_BUF(sizeof(struct nfsd4_deviceid) + 3 * 4);
1536 	COPYMEM(&gdev->gd_devid, sizeof(struct nfsd4_deviceid));
1537 	gdev->gd_layout_type = be32_to_cpup(p++);
1538 	gdev->gd_maxcount = be32_to_cpup(p++);
1539 	num = be32_to_cpup(p++);
1540 	if (num) {
1541 		READ_BUF(4 * num);
1542 		gdev->gd_notify_types = be32_to_cpup(p++);
1543 		for (i = 1; i < num; i++) {
1544 			if (be32_to_cpup(p++)) {
1545 				status = nfserr_inval;
1546 				goto out;
1547 			}
1548 		}
1549 	}
1550 	DECODE_TAIL;
1551 }
1552 
1553 static __be32
1554 nfsd4_decode_layoutget(struct nfsd4_compoundargs *argp,
1555 		struct nfsd4_layoutget *lgp)
1556 {
1557 	DECODE_HEAD;
1558 
1559 	READ_BUF(36);
1560 	lgp->lg_signal = be32_to_cpup(p++);
1561 	lgp->lg_layout_type = be32_to_cpup(p++);
1562 	lgp->lg_seg.iomode = be32_to_cpup(p++);
1563 	p = xdr_decode_hyper(p, &lgp->lg_seg.offset);
1564 	p = xdr_decode_hyper(p, &lgp->lg_seg.length);
1565 	p = xdr_decode_hyper(p, &lgp->lg_minlength);
1566 
1567 	status = nfsd4_decode_stateid(argp, &lgp->lg_sid);
1568 	if (status)
1569 		return status;
1570 
1571 	READ_BUF(4);
1572 	lgp->lg_maxcount = be32_to_cpup(p++);
1573 
1574 	DECODE_TAIL;
1575 }
1576 
1577 static __be32
1578 nfsd4_decode_layoutcommit(struct nfsd4_compoundargs *argp,
1579 		struct nfsd4_layoutcommit *lcp)
1580 {
1581 	DECODE_HEAD;
1582 	u32 timechange;
1583 
1584 	READ_BUF(20);
1585 	p = xdr_decode_hyper(p, &lcp->lc_seg.offset);
1586 	p = xdr_decode_hyper(p, &lcp->lc_seg.length);
1587 	lcp->lc_reclaim = be32_to_cpup(p++);
1588 
1589 	status = nfsd4_decode_stateid(argp, &lcp->lc_sid);
1590 	if (status)
1591 		return status;
1592 
1593 	READ_BUF(4);
1594 	lcp->lc_newoffset = be32_to_cpup(p++);
1595 	if (lcp->lc_newoffset) {
1596 		READ_BUF(8);
1597 		p = xdr_decode_hyper(p, &lcp->lc_last_wr);
1598 	} else
1599 		lcp->lc_last_wr = 0;
1600 	READ_BUF(4);
1601 	timechange = be32_to_cpup(p++);
1602 	if (timechange) {
1603 		status = nfsd4_decode_time(argp, &lcp->lc_mtime);
1604 		if (status)
1605 			return status;
1606 	} else {
1607 		lcp->lc_mtime.tv_nsec = UTIME_NOW;
1608 	}
1609 	READ_BUF(8);
1610 	lcp->lc_layout_type = be32_to_cpup(p++);
1611 
1612 	/*
1613 	 * Save the layout update in XDR format and let the layout driver deal
1614 	 * with it later.
1615 	 */
1616 	lcp->lc_up_len = be32_to_cpup(p++);
1617 	if (lcp->lc_up_len > 0) {
1618 		READ_BUF(lcp->lc_up_len);
1619 		READMEM(lcp->lc_up_layout, lcp->lc_up_len);
1620 	}
1621 
1622 	DECODE_TAIL;
1623 }
1624 
1625 static __be32
1626 nfsd4_decode_layoutreturn(struct nfsd4_compoundargs *argp,
1627 		struct nfsd4_layoutreturn *lrp)
1628 {
1629 	DECODE_HEAD;
1630 
1631 	READ_BUF(16);
1632 	lrp->lr_reclaim = be32_to_cpup(p++);
1633 	lrp->lr_layout_type = be32_to_cpup(p++);
1634 	lrp->lr_seg.iomode = be32_to_cpup(p++);
1635 	lrp->lr_return_type = be32_to_cpup(p++);
1636 	if (lrp->lr_return_type == RETURN_FILE) {
1637 		READ_BUF(16);
1638 		p = xdr_decode_hyper(p, &lrp->lr_seg.offset);
1639 		p = xdr_decode_hyper(p, &lrp->lr_seg.length);
1640 
1641 		status = nfsd4_decode_stateid(argp, &lrp->lr_sid);
1642 		if (status)
1643 			return status;
1644 
1645 		READ_BUF(4);
1646 		lrp->lrf_body_len = be32_to_cpup(p++);
1647 		if (lrp->lrf_body_len > 0) {
1648 			READ_BUF(lrp->lrf_body_len);
1649 			READMEM(lrp->lrf_body, lrp->lrf_body_len);
1650 		}
1651 	} else {
1652 		lrp->lr_seg.offset = 0;
1653 		lrp->lr_seg.length = NFS4_MAX_UINT64;
1654 	}
1655 
1656 	DECODE_TAIL;
1657 }
1658 #endif /* CONFIG_NFSD_PNFS */
1659 
1660 static __be32
1661 nfsd4_decode_fallocate(struct nfsd4_compoundargs *argp,
1662 		       struct nfsd4_fallocate *fallocate)
1663 {
1664 	DECODE_HEAD;
1665 
1666 	status = nfsd4_decode_stateid(argp, &fallocate->falloc_stateid);
1667 	if (status)
1668 		return status;
1669 
1670 	READ_BUF(16);
1671 	p = xdr_decode_hyper(p, &fallocate->falloc_offset);
1672 	xdr_decode_hyper(p, &fallocate->falloc_length);
1673 
1674 	DECODE_TAIL;
1675 }
1676 
1677 static __be32
1678 nfsd4_decode_clone(struct nfsd4_compoundargs *argp, struct nfsd4_clone *clone)
1679 {
1680 	DECODE_HEAD;
1681 
1682 	status = nfsd4_decode_stateid(argp, &clone->cl_src_stateid);
1683 	if (status)
1684 		return status;
1685 	status = nfsd4_decode_stateid(argp, &clone->cl_dst_stateid);
1686 	if (status)
1687 		return status;
1688 
1689 	READ_BUF(8 + 8 + 8);
1690 	p = xdr_decode_hyper(p, &clone->cl_src_pos);
1691 	p = xdr_decode_hyper(p, &clone->cl_dst_pos);
1692 	p = xdr_decode_hyper(p, &clone->cl_count);
1693 	DECODE_TAIL;
1694 }
1695 
1696 static __be32
1697 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
1698 {
1699 	DECODE_HEAD;
1700 
1701 	status = nfsd4_decode_stateid(argp, &seek->seek_stateid);
1702 	if (status)
1703 		return status;
1704 
1705 	READ_BUF(8 + 4);
1706 	p = xdr_decode_hyper(p, &seek->seek_offset);
1707 	seek->seek_whence = be32_to_cpup(p);
1708 
1709 	DECODE_TAIL;
1710 }
1711 
1712 static __be32
1713 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1714 {
1715 	return nfs_ok;
1716 }
1717 
1718 static __be32
1719 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1720 {
1721 	return nfserr_notsupp;
1722 }
1723 
1724 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1725 
1726 static nfsd4_dec nfsd4_dec_ops[] = {
1727 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1728 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1729 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1730 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1731 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1732 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1733 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1734 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1735 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1736 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1737 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1738 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1739 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1740 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1741 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1742 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1743 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1744 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1745 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1746 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1747 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_putpubfh,
1748 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1749 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1750 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1751 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1752 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1753 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1754 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1755 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1756 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1757 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1758 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1759 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1760 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1761 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1762 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1763 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1764 
1765 	/* new operations for NFSv4.1 */
1766 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_backchannel_ctl,
1767 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1768 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1769 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1770 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1771 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
1772 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1773 #ifdef CONFIG_NFSD_PNFS
1774 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_getdeviceinfo,
1775 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1776 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_layoutcommit,
1777 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_layoutget,
1778 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_layoutreturn,
1779 #else
1780 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1781 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1782 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1783 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1784 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1785 #endif
1786 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1787 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1788 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1789 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
1790 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1791 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
1792 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1793 
1794 	/* new operations for NFSv4.2 */
1795 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1796 	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_notsupp,
1797 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
1798 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1799 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1800 	[OP_LAYOUTERROR]	= (nfsd4_dec)nfsd4_decode_notsupp,
1801 	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1802 	[OP_OFFLOAD_CANCEL]	= (nfsd4_dec)nfsd4_decode_notsupp,
1803 	[OP_OFFLOAD_STATUS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1804 	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_notsupp,
1805 	[OP_SEEK]		= (nfsd4_dec)nfsd4_decode_seek,
1806 	[OP_WRITE_SAME]		= (nfsd4_dec)nfsd4_decode_notsupp,
1807 	[OP_CLONE]		= (nfsd4_dec)nfsd4_decode_clone,
1808 };
1809 
1810 static inline bool
1811 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
1812 {
1813 	if (op->opnum < FIRST_NFS4_OP)
1814 		return false;
1815 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
1816 		return false;
1817 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
1818 		return false;
1819 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
1820 		return false;
1821 	return true;
1822 }
1823 
1824 static __be32
1825 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1826 {
1827 	DECODE_HEAD;
1828 	struct nfsd4_op *op;
1829 	bool cachethis = false;
1830 	int auth_slack= argp->rqstp->rq_auth_slack;
1831 	int max_reply = auth_slack + 8; /* opcnt, status */
1832 	int readcount = 0;
1833 	int readbytes = 0;
1834 	int i;
1835 
1836 	READ_BUF(4);
1837 	argp->taglen = be32_to_cpup(p++);
1838 	READ_BUF(argp->taglen + 8);
1839 	SAVEMEM(argp->tag, argp->taglen);
1840 	argp->minorversion = be32_to_cpup(p++);
1841 	argp->opcnt = be32_to_cpup(p++);
1842 	max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
1843 
1844 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1845 		goto xdr_error;
1846 	if (argp->opcnt > 100)
1847 		goto xdr_error;
1848 
1849 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1850 		argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1851 		if (!argp->ops) {
1852 			argp->ops = argp->iops;
1853 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1854 			goto xdr_error;
1855 		}
1856 	}
1857 
1858 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
1859 		argp->opcnt = 0;
1860 
1861 	for (i = 0; i < argp->opcnt; i++) {
1862 		op = &argp->ops[i];
1863 		op->replay = NULL;
1864 
1865 		READ_BUF(4);
1866 		op->opnum = be32_to_cpup(p++);
1867 
1868 		if (nfsd4_opnum_in_range(argp, op))
1869 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
1870 		else {
1871 			op->opnum = OP_ILLEGAL;
1872 			op->status = nfserr_op_illegal;
1873 		}
1874 		/*
1875 		 * We'll try to cache the result in the DRC if any one
1876 		 * op in the compound wants to be cached:
1877 		 */
1878 		cachethis |= nfsd4_cache_this_op(op);
1879 
1880 		if (op->opnum == OP_READ) {
1881 			readcount++;
1882 			readbytes += nfsd4_max_reply(argp->rqstp, op);
1883 		} else
1884 			max_reply += nfsd4_max_reply(argp->rqstp, op);
1885 		/*
1886 		 * OP_LOCK may return a conflicting lock.  (Special case
1887 		 * because it will just skip encoding this if it runs
1888 		 * out of xdr buffer space, and it is the only operation
1889 		 * that behaves this way.)
1890 		 */
1891 		if (op->opnum == OP_LOCK)
1892 			max_reply += NFS4_OPAQUE_LIMIT;
1893 
1894 		if (op->status) {
1895 			argp->opcnt = i+1;
1896 			break;
1897 		}
1898 	}
1899 	/* Sessions make the DRC unnecessary: */
1900 	if (argp->minorversion)
1901 		cachethis = false;
1902 	svc_reserve(argp->rqstp, max_reply + readbytes);
1903 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1904 
1905 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
1906 		clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
1907 
1908 	DECODE_TAIL;
1909 }
1910 
1911 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode)
1912 {
1913 	if (IS_I_VERSION(inode)) {
1914 		p = xdr_encode_hyper(p, inode->i_version);
1915 	} else {
1916 		*p++ = cpu_to_be32(stat->ctime.tv_sec);
1917 		*p++ = cpu_to_be32(stat->ctime.tv_nsec);
1918 	}
1919 	return p;
1920 }
1921 
1922 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
1923 {
1924 	*p++ = cpu_to_be32(c->atomic);
1925 	if (c->change_supported) {
1926 		p = xdr_encode_hyper(p, c->before_change);
1927 		p = xdr_encode_hyper(p, c->after_change);
1928 	} else {
1929 		*p++ = cpu_to_be32(c->before_ctime_sec);
1930 		*p++ = cpu_to_be32(c->before_ctime_nsec);
1931 		*p++ = cpu_to_be32(c->after_ctime_sec);
1932 		*p++ = cpu_to_be32(c->after_ctime_nsec);
1933 	}
1934 	return p;
1935 }
1936 
1937 /* Encode as an array of strings the string given with components
1938  * separated @sep, escaped with esc_enter and esc_exit.
1939  */
1940 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
1941 					  char *components, char esc_enter,
1942 					  char esc_exit)
1943 {
1944 	__be32 *p;
1945 	__be32 pathlen;
1946 	int pathlen_offset;
1947 	int strlen, count=0;
1948 	char *str, *end, *next;
1949 
1950 	dprintk("nfsd4_encode_components(%s)\n", components);
1951 
1952 	pathlen_offset = xdr->buf->len;
1953 	p = xdr_reserve_space(xdr, 4);
1954 	if (!p)
1955 		return nfserr_resource;
1956 	p++; /* We will fill this in with @count later */
1957 
1958 	end = str = components;
1959 	while (*end) {
1960 		bool found_esc = false;
1961 
1962 		/* try to parse as esc_start, ..., esc_end, sep */
1963 		if (*str == esc_enter) {
1964 			for (; *end && (*end != esc_exit); end++)
1965 				/* find esc_exit or end of string */;
1966 			next = end + 1;
1967 			if (*end && (!*next || *next == sep)) {
1968 				str++;
1969 				found_esc = true;
1970 			}
1971 		}
1972 
1973 		if (!found_esc)
1974 			for (; *end && (*end != sep); end++)
1975 				/* find sep or end of string */;
1976 
1977 		strlen = end - str;
1978 		if (strlen) {
1979 			p = xdr_reserve_space(xdr, strlen + 4);
1980 			if (!p)
1981 				return nfserr_resource;
1982 			p = xdr_encode_opaque(p, str, strlen);
1983 			count++;
1984 		}
1985 		else
1986 			end++;
1987 		if (found_esc)
1988 			end = next;
1989 
1990 		str = end;
1991 	}
1992 	pathlen = htonl(count);
1993 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
1994 	return 0;
1995 }
1996 
1997 /* Encode as an array of strings the string given with components
1998  * separated @sep.
1999  */
2000 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
2001 				      char *components)
2002 {
2003 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
2004 }
2005 
2006 /*
2007  * encode a location element of a fs_locations structure
2008  */
2009 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
2010 					struct nfsd4_fs_location *location)
2011 {
2012 	__be32 status;
2013 
2014 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
2015 						'[', ']');
2016 	if (status)
2017 		return status;
2018 	status = nfsd4_encode_components(xdr, '/', location->path);
2019 	if (status)
2020 		return status;
2021 	return 0;
2022 }
2023 
2024 /*
2025  * Encode a path in RFC3530 'pathname4' format
2026  */
2027 static __be32 nfsd4_encode_path(struct xdr_stream *xdr,
2028 				const struct path *root,
2029 				const struct path *path)
2030 {
2031 	struct path cur = *path;
2032 	__be32 *p;
2033 	struct dentry **components = NULL;
2034 	unsigned int ncomponents = 0;
2035 	__be32 err = nfserr_jukebox;
2036 
2037 	dprintk("nfsd4_encode_components(");
2038 
2039 	path_get(&cur);
2040 	/* First walk the path up to the nfsd root, and store the
2041 	 * dentries/path components in an array.
2042 	 */
2043 	for (;;) {
2044 		if (path_equal(&cur, root))
2045 			break;
2046 		if (cur.dentry == cur.mnt->mnt_root) {
2047 			if (follow_up(&cur))
2048 				continue;
2049 			goto out_free;
2050 		}
2051 		if ((ncomponents & 15) == 0) {
2052 			struct dentry **new;
2053 			new = krealloc(components,
2054 					sizeof(*new) * (ncomponents + 16),
2055 					GFP_KERNEL);
2056 			if (!new)
2057 				goto out_free;
2058 			components = new;
2059 		}
2060 		components[ncomponents++] = cur.dentry;
2061 		cur.dentry = dget_parent(cur.dentry);
2062 	}
2063 	err = nfserr_resource;
2064 	p = xdr_reserve_space(xdr, 4);
2065 	if (!p)
2066 		goto out_free;
2067 	*p++ = cpu_to_be32(ncomponents);
2068 
2069 	while (ncomponents) {
2070 		struct dentry *dentry = components[ncomponents - 1];
2071 		unsigned int len;
2072 
2073 		spin_lock(&dentry->d_lock);
2074 		len = dentry->d_name.len;
2075 		p = xdr_reserve_space(xdr, len + 4);
2076 		if (!p) {
2077 			spin_unlock(&dentry->d_lock);
2078 			goto out_free;
2079 		}
2080 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
2081 		dprintk("/%pd", dentry);
2082 		spin_unlock(&dentry->d_lock);
2083 		dput(dentry);
2084 		ncomponents--;
2085 	}
2086 
2087 	err = 0;
2088 out_free:
2089 	dprintk(")\n");
2090 	while (ncomponents)
2091 		dput(components[--ncomponents]);
2092 	kfree(components);
2093 	path_put(&cur);
2094 	return err;
2095 }
2096 
2097 static __be32 nfsd4_encode_fsloc_fsroot(struct xdr_stream *xdr,
2098 			struct svc_rqst *rqstp, const struct path *path)
2099 {
2100 	struct svc_export *exp_ps;
2101 	__be32 res;
2102 
2103 	exp_ps = rqst_find_fsidzero_export(rqstp);
2104 	if (IS_ERR(exp_ps))
2105 		return nfserrno(PTR_ERR(exp_ps));
2106 	res = nfsd4_encode_path(xdr, &exp_ps->ex_path, path);
2107 	exp_put(exp_ps);
2108 	return res;
2109 }
2110 
2111 /*
2112  *  encode a fs_locations structure
2113  */
2114 static __be32 nfsd4_encode_fs_locations(struct xdr_stream *xdr,
2115 			struct svc_rqst *rqstp, struct svc_export *exp)
2116 {
2117 	__be32 status;
2118 	int i;
2119 	__be32 *p;
2120 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
2121 
2122 	status = nfsd4_encode_fsloc_fsroot(xdr, rqstp, &exp->ex_path);
2123 	if (status)
2124 		return status;
2125 	p = xdr_reserve_space(xdr, 4);
2126 	if (!p)
2127 		return nfserr_resource;
2128 	*p++ = cpu_to_be32(fslocs->locations_count);
2129 	for (i=0; i<fslocs->locations_count; i++) {
2130 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
2131 		if (status)
2132 			return status;
2133 	}
2134 	return 0;
2135 }
2136 
2137 static u32 nfs4_file_type(umode_t mode)
2138 {
2139 	switch (mode & S_IFMT) {
2140 	case S_IFIFO:	return NF4FIFO;
2141 	case S_IFCHR:	return NF4CHR;
2142 	case S_IFDIR:	return NF4DIR;
2143 	case S_IFBLK:	return NF4BLK;
2144 	case S_IFLNK:	return NF4LNK;
2145 	case S_IFREG:	return NF4REG;
2146 	case S_IFSOCK:	return NF4SOCK;
2147 	default:	return NF4BAD;
2148 	};
2149 }
2150 
2151 static inline __be32
2152 nfsd4_encode_aclname(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2153 		     struct nfs4_ace *ace)
2154 {
2155 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
2156 		return nfs4_acl_write_who(xdr, ace->whotype);
2157 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
2158 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
2159 	else
2160 		return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
2161 }
2162 
2163 static inline __be32
2164 nfsd4_encode_layout_type(struct xdr_stream *xdr, enum pnfs_layouttype layout_type)
2165 {
2166 	__be32 *p;
2167 
2168 	if (layout_type) {
2169 		p = xdr_reserve_space(xdr, 8);
2170 		if (!p)
2171 			return nfserr_resource;
2172 		*p++ = cpu_to_be32(1);
2173 		*p++ = cpu_to_be32(layout_type);
2174 	} else {
2175 		p = xdr_reserve_space(xdr, 4);
2176 		if (!p)
2177 			return nfserr_resource;
2178 		*p++ = cpu_to_be32(0);
2179 	}
2180 
2181 	return 0;
2182 }
2183 
2184 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
2185 			      FATTR4_WORD0_RDATTR_ERROR)
2186 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2187 #define WORD2_ABSENT_FS_ATTRS 0
2188 
2189 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2190 static inline __be32
2191 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2192 			    void *context, int len)
2193 {
2194 	__be32 *p;
2195 
2196 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2197 	if (!p)
2198 		return nfserr_resource;
2199 
2200 	/*
2201 	 * For now we use a 0 here to indicate the null translation; in
2202 	 * the future we may place a call to translation code here.
2203 	 */
2204 	*p++ = cpu_to_be32(0); /* lfs */
2205 	*p++ = cpu_to_be32(0); /* pi */
2206 	p = xdr_encode_opaque(p, context, len);
2207 	return 0;
2208 }
2209 #else
2210 static inline __be32
2211 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2212 			    void *context, int len)
2213 { return 0; }
2214 #endif
2215 
2216 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *bmval2, u32 *rdattr_err)
2217 {
2218 	/* As per referral draft:  */
2219 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2220 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2221 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2222 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2223 			*rdattr_err = NFSERR_MOVED;
2224 		else
2225 			return nfserr_moved;
2226 	}
2227 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2228 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2229 	*bmval2 &= WORD2_ABSENT_FS_ATTRS;
2230 	return 0;
2231 }
2232 
2233 
2234 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2235 {
2236 	struct path path = exp->ex_path;
2237 	int err;
2238 
2239 	path_get(&path);
2240 	while (follow_up(&path)) {
2241 		if (path.dentry != path.mnt->mnt_root)
2242 			break;
2243 	}
2244 	err = vfs_getattr(&path, stat);
2245 	path_put(&path);
2246 	return err;
2247 }
2248 
2249 static __be32
2250 nfsd4_encode_bitmap(struct xdr_stream *xdr, u32 bmval0, u32 bmval1, u32 bmval2)
2251 {
2252 	__be32 *p;
2253 
2254 	if (bmval2) {
2255 		p = xdr_reserve_space(xdr, 16);
2256 		if (!p)
2257 			goto out_resource;
2258 		*p++ = cpu_to_be32(3);
2259 		*p++ = cpu_to_be32(bmval0);
2260 		*p++ = cpu_to_be32(bmval1);
2261 		*p++ = cpu_to_be32(bmval2);
2262 	} else if (bmval1) {
2263 		p = xdr_reserve_space(xdr, 12);
2264 		if (!p)
2265 			goto out_resource;
2266 		*p++ = cpu_to_be32(2);
2267 		*p++ = cpu_to_be32(bmval0);
2268 		*p++ = cpu_to_be32(bmval1);
2269 	} else {
2270 		p = xdr_reserve_space(xdr, 8);
2271 		if (!p)
2272 			goto out_resource;
2273 		*p++ = cpu_to_be32(1);
2274 		*p++ = cpu_to_be32(bmval0);
2275 	}
2276 
2277 	return 0;
2278 out_resource:
2279 	return nfserr_resource;
2280 }
2281 
2282 /*
2283  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2284  * ourselves.
2285  */
2286 static __be32
2287 nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
2288 		struct svc_export *exp,
2289 		struct dentry *dentry, u32 *bmval,
2290 		struct svc_rqst *rqstp, int ignore_crossmnt)
2291 {
2292 	u32 bmval0 = bmval[0];
2293 	u32 bmval1 = bmval[1];
2294 	u32 bmval2 = bmval[2];
2295 	struct kstat stat;
2296 	struct svc_fh *tempfh = NULL;
2297 	struct kstatfs statfs;
2298 	__be32 *p;
2299 	int starting_len = xdr->buf->len;
2300 	int attrlen_offset;
2301 	__be32 attrlen;
2302 	u32 dummy;
2303 	u64 dummy64;
2304 	u32 rdattr_err = 0;
2305 	__be32 status;
2306 	int err;
2307 	struct nfs4_acl *acl = NULL;
2308 	void *context = NULL;
2309 	int contextlen;
2310 	bool contextsupport = false;
2311 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2312 	u32 minorversion = resp->cstate.minorversion;
2313 	struct path path = {
2314 		.mnt	= exp->ex_path.mnt,
2315 		.dentry	= dentry,
2316 	};
2317 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2318 
2319 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2320 	BUG_ON(bmval0 & ~nfsd_suppattrs0(minorversion));
2321 	BUG_ON(bmval1 & ~nfsd_suppattrs1(minorversion));
2322 	BUG_ON(bmval2 & ~nfsd_suppattrs2(minorversion));
2323 
2324 	if (exp->ex_fslocs.migrated) {
2325 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &bmval2, &rdattr_err);
2326 		if (status)
2327 			goto out;
2328 	}
2329 
2330 	err = vfs_getattr(&path, &stat);
2331 	if (err)
2332 		goto out_nfserr;
2333 	if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
2334 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
2335 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2336 		       FATTR4_WORD1_SPACE_TOTAL))) {
2337 		err = vfs_statfs(&path, &statfs);
2338 		if (err)
2339 			goto out_nfserr;
2340 	}
2341 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2342 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2343 		status = nfserr_jukebox;
2344 		if (!tempfh)
2345 			goto out;
2346 		fh_init(tempfh, NFS4_FHSIZE);
2347 		status = fh_compose(tempfh, exp, dentry, NULL);
2348 		if (status)
2349 			goto out;
2350 		fhp = tempfh;
2351 	}
2352 	if (bmval0 & FATTR4_WORD0_ACL) {
2353 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2354 		if (err == -EOPNOTSUPP)
2355 			bmval0 &= ~FATTR4_WORD0_ACL;
2356 		else if (err == -EINVAL) {
2357 			status = nfserr_attrnotsupp;
2358 			goto out;
2359 		} else if (err != 0)
2360 			goto out_nfserr;
2361 	}
2362 
2363 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2364 	if ((bmval2 & FATTR4_WORD2_SECURITY_LABEL) ||
2365 	     bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2366 		err = security_inode_getsecctx(d_inode(dentry),
2367 						&context, &contextlen);
2368 		contextsupport = (err == 0);
2369 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2370 			if (err == -EOPNOTSUPP)
2371 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2372 			else if (err)
2373 				goto out_nfserr;
2374 		}
2375 	}
2376 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2377 
2378 	status = nfsd4_encode_bitmap(xdr, bmval0, bmval1, bmval2);
2379 	if (status)
2380 		goto out;
2381 
2382 	attrlen_offset = xdr->buf->len;
2383 	p = xdr_reserve_space(xdr, 4);
2384 	if (!p)
2385 		goto out_resource;
2386 	p++;                /* to be backfilled later */
2387 
2388 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2389 		u32 word0 = nfsd_suppattrs0(minorversion);
2390 		u32 word1 = nfsd_suppattrs1(minorversion);
2391 		u32 word2 = nfsd_suppattrs2(minorversion);
2392 
2393 		if (!IS_POSIXACL(dentry->d_inode))
2394 			word0 &= ~FATTR4_WORD0_ACL;
2395 		if (!contextsupport)
2396 			word2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2397 		if (!word2) {
2398 			p = xdr_reserve_space(xdr, 12);
2399 			if (!p)
2400 				goto out_resource;
2401 			*p++ = cpu_to_be32(2);
2402 			*p++ = cpu_to_be32(word0);
2403 			*p++ = cpu_to_be32(word1);
2404 		} else {
2405 			p = xdr_reserve_space(xdr, 16);
2406 			if (!p)
2407 				goto out_resource;
2408 			*p++ = cpu_to_be32(3);
2409 			*p++ = cpu_to_be32(word0);
2410 			*p++ = cpu_to_be32(word1);
2411 			*p++ = cpu_to_be32(word2);
2412 		}
2413 	}
2414 	if (bmval0 & FATTR4_WORD0_TYPE) {
2415 		p = xdr_reserve_space(xdr, 4);
2416 		if (!p)
2417 			goto out_resource;
2418 		dummy = nfs4_file_type(stat.mode);
2419 		if (dummy == NF4BAD) {
2420 			status = nfserr_serverfault;
2421 			goto out;
2422 		}
2423 		*p++ = cpu_to_be32(dummy);
2424 	}
2425 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2426 		p = xdr_reserve_space(xdr, 4);
2427 		if (!p)
2428 			goto out_resource;
2429 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2430 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT);
2431 		else
2432 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT|
2433 						NFS4_FH_VOL_RENAME);
2434 	}
2435 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2436 		p = xdr_reserve_space(xdr, 8);
2437 		if (!p)
2438 			goto out_resource;
2439 		p = encode_change(p, &stat, d_inode(dentry));
2440 	}
2441 	if (bmval0 & FATTR4_WORD0_SIZE) {
2442 		p = xdr_reserve_space(xdr, 8);
2443 		if (!p)
2444 			goto out_resource;
2445 		p = xdr_encode_hyper(p, stat.size);
2446 	}
2447 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2448 		p = xdr_reserve_space(xdr, 4);
2449 		if (!p)
2450 			goto out_resource;
2451 		*p++ = cpu_to_be32(1);
2452 	}
2453 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2454 		p = xdr_reserve_space(xdr, 4);
2455 		if (!p)
2456 			goto out_resource;
2457 		*p++ = cpu_to_be32(1);
2458 	}
2459 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2460 		p = xdr_reserve_space(xdr, 4);
2461 		if (!p)
2462 			goto out_resource;
2463 		*p++ = cpu_to_be32(0);
2464 	}
2465 	if (bmval0 & FATTR4_WORD0_FSID) {
2466 		p = xdr_reserve_space(xdr, 16);
2467 		if (!p)
2468 			goto out_resource;
2469 		if (exp->ex_fslocs.migrated) {
2470 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
2471 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
2472 		} else switch(fsid_source(fhp)) {
2473 		case FSIDSOURCE_FSID:
2474 			p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
2475 			p = xdr_encode_hyper(p, (u64)0);
2476 			break;
2477 		case FSIDSOURCE_DEV:
2478 			*p++ = cpu_to_be32(0);
2479 			*p++ = cpu_to_be32(MAJOR(stat.dev));
2480 			*p++ = cpu_to_be32(0);
2481 			*p++ = cpu_to_be32(MINOR(stat.dev));
2482 			break;
2483 		case FSIDSOURCE_UUID:
2484 			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
2485 								EX_UUID_LEN);
2486 			break;
2487 		}
2488 	}
2489 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2490 		p = xdr_reserve_space(xdr, 4);
2491 		if (!p)
2492 			goto out_resource;
2493 		*p++ = cpu_to_be32(0);
2494 	}
2495 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2496 		p = xdr_reserve_space(xdr, 4);
2497 		if (!p)
2498 			goto out_resource;
2499 		*p++ = cpu_to_be32(nn->nfsd4_lease);
2500 	}
2501 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2502 		p = xdr_reserve_space(xdr, 4);
2503 		if (!p)
2504 			goto out_resource;
2505 		*p++ = cpu_to_be32(rdattr_err);
2506 	}
2507 	if (bmval0 & FATTR4_WORD0_ACL) {
2508 		struct nfs4_ace *ace;
2509 
2510 		if (acl == NULL) {
2511 			p = xdr_reserve_space(xdr, 4);
2512 			if (!p)
2513 				goto out_resource;
2514 
2515 			*p++ = cpu_to_be32(0);
2516 			goto out_acl;
2517 		}
2518 		p = xdr_reserve_space(xdr, 4);
2519 		if (!p)
2520 			goto out_resource;
2521 		*p++ = cpu_to_be32(acl->naces);
2522 
2523 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2524 			p = xdr_reserve_space(xdr, 4*3);
2525 			if (!p)
2526 				goto out_resource;
2527 			*p++ = cpu_to_be32(ace->type);
2528 			*p++ = cpu_to_be32(ace->flag);
2529 			*p++ = cpu_to_be32(ace->access_mask &
2530 							NFS4_ACE_MASK_ALL);
2531 			status = nfsd4_encode_aclname(xdr, rqstp, ace);
2532 			if (status)
2533 				goto out;
2534 		}
2535 	}
2536 out_acl:
2537 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2538 		p = xdr_reserve_space(xdr, 4);
2539 		if (!p)
2540 			goto out_resource;
2541 		*p++ = cpu_to_be32(IS_POSIXACL(dentry->d_inode) ?
2542 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2543 	}
2544 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2545 		p = xdr_reserve_space(xdr, 4);
2546 		if (!p)
2547 			goto out_resource;
2548 		*p++ = cpu_to_be32(1);
2549 	}
2550 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2551 		p = xdr_reserve_space(xdr, 4);
2552 		if (!p)
2553 			goto out_resource;
2554 		*p++ = cpu_to_be32(0);
2555 	}
2556 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2557 		p = xdr_reserve_space(xdr, 4);
2558 		if (!p)
2559 			goto out_resource;
2560 		*p++ = cpu_to_be32(1);
2561 	}
2562 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2563 		p = xdr_reserve_space(xdr, 4);
2564 		if (!p)
2565 			goto out_resource;
2566 		*p++ = cpu_to_be32(1);
2567 	}
2568 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2569 		p = xdr_reserve_space(xdr, fhp->fh_handle.fh_size + 4);
2570 		if (!p)
2571 			goto out_resource;
2572 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base,
2573 					fhp->fh_handle.fh_size);
2574 	}
2575 	if (bmval0 & FATTR4_WORD0_FILEID) {
2576 		p = xdr_reserve_space(xdr, 8);
2577 		if (!p)
2578 			goto out_resource;
2579 		p = xdr_encode_hyper(p, stat.ino);
2580 	}
2581 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2582 		p = xdr_reserve_space(xdr, 8);
2583 		if (!p)
2584 			goto out_resource;
2585 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2586 	}
2587 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2588 		p = xdr_reserve_space(xdr, 8);
2589 		if (!p)
2590 			goto out_resource;
2591 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2592 	}
2593 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2594 		p = xdr_reserve_space(xdr, 8);
2595 		if (!p)
2596 			goto out_resource;
2597 		p = xdr_encode_hyper(p, (u64) statfs.f_files);
2598 	}
2599 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2600 		status = nfsd4_encode_fs_locations(xdr, rqstp, exp);
2601 		if (status)
2602 			goto out;
2603 	}
2604 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2605 		p = xdr_reserve_space(xdr, 4);
2606 		if (!p)
2607 			goto out_resource;
2608 		*p++ = cpu_to_be32(1);
2609 	}
2610 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2611 		p = xdr_reserve_space(xdr, 8);
2612 		if (!p)
2613 			goto out_resource;
2614 		p = xdr_encode_hyper(p, exp->ex_path.mnt->mnt_sb->s_maxbytes);
2615 	}
2616 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2617 		p = xdr_reserve_space(xdr, 4);
2618 		if (!p)
2619 			goto out_resource;
2620 		*p++ = cpu_to_be32(255);
2621 	}
2622 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2623 		p = xdr_reserve_space(xdr, 4);
2624 		if (!p)
2625 			goto out_resource;
2626 		*p++ = cpu_to_be32(statfs.f_namelen);
2627 	}
2628 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2629 		p = xdr_reserve_space(xdr, 8);
2630 		if (!p)
2631 			goto out_resource;
2632 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2633 	}
2634 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2635 		p = xdr_reserve_space(xdr, 8);
2636 		if (!p)
2637 			goto out_resource;
2638 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2639 	}
2640 	if (bmval1 & FATTR4_WORD1_MODE) {
2641 		p = xdr_reserve_space(xdr, 4);
2642 		if (!p)
2643 			goto out_resource;
2644 		*p++ = cpu_to_be32(stat.mode & S_IALLUGO);
2645 	}
2646 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2647 		p = xdr_reserve_space(xdr, 4);
2648 		if (!p)
2649 			goto out_resource;
2650 		*p++ = cpu_to_be32(1);
2651 	}
2652 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2653 		p = xdr_reserve_space(xdr, 4);
2654 		if (!p)
2655 			goto out_resource;
2656 		*p++ = cpu_to_be32(stat.nlink);
2657 	}
2658 	if (bmval1 & FATTR4_WORD1_OWNER) {
2659 		status = nfsd4_encode_user(xdr, rqstp, stat.uid);
2660 		if (status)
2661 			goto out;
2662 	}
2663 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2664 		status = nfsd4_encode_group(xdr, rqstp, stat.gid);
2665 		if (status)
2666 			goto out;
2667 	}
2668 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2669 		p = xdr_reserve_space(xdr, 8);
2670 		if (!p)
2671 			goto out_resource;
2672 		*p++ = cpu_to_be32((u32) MAJOR(stat.rdev));
2673 		*p++ = cpu_to_be32((u32) MINOR(stat.rdev));
2674 	}
2675 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2676 		p = xdr_reserve_space(xdr, 8);
2677 		if (!p)
2678 			goto out_resource;
2679 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2680 		p = xdr_encode_hyper(p, dummy64);
2681 	}
2682 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2683 		p = xdr_reserve_space(xdr, 8);
2684 		if (!p)
2685 			goto out_resource;
2686 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2687 		p = xdr_encode_hyper(p, dummy64);
2688 	}
2689 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2690 		p = xdr_reserve_space(xdr, 8);
2691 		if (!p)
2692 			goto out_resource;
2693 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2694 		p = xdr_encode_hyper(p, dummy64);
2695 	}
2696 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2697 		p = xdr_reserve_space(xdr, 8);
2698 		if (!p)
2699 			goto out_resource;
2700 		dummy64 = (u64)stat.blocks << 9;
2701 		p = xdr_encode_hyper(p, dummy64);
2702 	}
2703 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2704 		p = xdr_reserve_space(xdr, 12);
2705 		if (!p)
2706 			goto out_resource;
2707 		p = xdr_encode_hyper(p, (s64)stat.atime.tv_sec);
2708 		*p++ = cpu_to_be32(stat.atime.tv_nsec);
2709 	}
2710 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2711 		p = xdr_reserve_space(xdr, 12);
2712 		if (!p)
2713 			goto out_resource;
2714 		*p++ = cpu_to_be32(0);
2715 		*p++ = cpu_to_be32(1);
2716 		*p++ = cpu_to_be32(0);
2717 	}
2718 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2719 		p = xdr_reserve_space(xdr, 12);
2720 		if (!p)
2721 			goto out_resource;
2722 		p = xdr_encode_hyper(p, (s64)stat.ctime.tv_sec);
2723 		*p++ = cpu_to_be32(stat.ctime.tv_nsec);
2724 	}
2725 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2726 		p = xdr_reserve_space(xdr, 12);
2727 		if (!p)
2728 			goto out_resource;
2729 		p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
2730 		*p++ = cpu_to_be32(stat.mtime.tv_nsec);
2731 	}
2732 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2733 		struct kstat parent_stat;
2734 		u64 ino = stat.ino;
2735 
2736 		p = xdr_reserve_space(xdr, 8);
2737 		if (!p)
2738                 	goto out_resource;
2739 		/*
2740 		 * Get parent's attributes if not ignoring crossmount
2741 		 * and this is the root of a cross-mounted filesystem.
2742 		 */
2743 		if (ignore_crossmnt == 0 &&
2744 		    dentry == exp->ex_path.mnt->mnt_root) {
2745 			err = get_parent_attributes(exp, &parent_stat);
2746 			if (err)
2747 				goto out_nfserr;
2748 			ino = parent_stat.ino;
2749 		}
2750 		p = xdr_encode_hyper(p, ino);
2751 	}
2752 #ifdef CONFIG_NFSD_PNFS
2753 	if (bmval1 & FATTR4_WORD1_FS_LAYOUT_TYPES) {
2754 		status = nfsd4_encode_layout_type(xdr, exp->ex_layout_type);
2755 		if (status)
2756 			goto out;
2757 	}
2758 
2759 	if (bmval2 & FATTR4_WORD2_LAYOUT_TYPES) {
2760 		status = nfsd4_encode_layout_type(xdr, exp->ex_layout_type);
2761 		if (status)
2762 			goto out;
2763 	}
2764 
2765 	if (bmval2 & FATTR4_WORD2_LAYOUT_BLKSIZE) {
2766 		p = xdr_reserve_space(xdr, 4);
2767 		if (!p)
2768 			goto out_resource;
2769 		*p++ = cpu_to_be32(stat.blksize);
2770 	}
2771 #endif /* CONFIG_NFSD_PNFS */
2772 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2773 		status = nfsd4_encode_bitmap(xdr, NFSD_SUPPATTR_EXCLCREAT_WORD0,
2774 						  NFSD_SUPPATTR_EXCLCREAT_WORD1,
2775 						  NFSD_SUPPATTR_EXCLCREAT_WORD2);
2776 		if (status)
2777 			goto out;
2778 	}
2779 
2780 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2781 		status = nfsd4_encode_security_label(xdr, rqstp, context,
2782 								contextlen);
2783 		if (status)
2784 			goto out;
2785 	}
2786 
2787 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
2788 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
2789 	status = nfs_ok;
2790 
2791 out:
2792 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2793 	if (context)
2794 		security_release_secctx(context, contextlen);
2795 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2796 	kfree(acl);
2797 	if (tempfh) {
2798 		fh_put(tempfh);
2799 		kfree(tempfh);
2800 	}
2801 	if (status)
2802 		xdr_truncate_encode(xdr, starting_len);
2803 	return status;
2804 out_nfserr:
2805 	status = nfserrno(err);
2806 	goto out;
2807 out_resource:
2808 	status = nfserr_resource;
2809 	goto out;
2810 }
2811 
2812 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
2813 				struct xdr_buf *buf, __be32 *p, int bytes)
2814 {
2815 	xdr->scratch.iov_len = 0;
2816 	memset(buf, 0, sizeof(struct xdr_buf));
2817 	buf->head[0].iov_base = p;
2818 	buf->head[0].iov_len = 0;
2819 	buf->len = 0;
2820 	xdr->buf = buf;
2821 	xdr->iov = buf->head;
2822 	xdr->p = p;
2823 	xdr->end = (void *)p + bytes;
2824 	buf->buflen = bytes;
2825 }
2826 
2827 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
2828 			struct svc_fh *fhp, struct svc_export *exp,
2829 			struct dentry *dentry, u32 *bmval,
2830 			struct svc_rqst *rqstp, int ignore_crossmnt)
2831 {
2832 	struct xdr_buf dummy;
2833 	struct xdr_stream xdr;
2834 	__be32 ret;
2835 
2836 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
2837 	ret = nfsd4_encode_fattr(&xdr, fhp, exp, dentry, bmval, rqstp,
2838 							ignore_crossmnt);
2839 	*p = xdr.p;
2840 	return ret;
2841 }
2842 
2843 static inline int attributes_need_mount(u32 *bmval)
2844 {
2845 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2846 		return 1;
2847 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2848 		return 1;
2849 	return 0;
2850 }
2851 
2852 static __be32
2853 nfsd4_encode_dirent_fattr(struct xdr_stream *xdr, struct nfsd4_readdir *cd,
2854 			const char *name, int namlen)
2855 {
2856 	struct svc_export *exp = cd->rd_fhp->fh_export;
2857 	struct dentry *dentry;
2858 	__be32 nfserr;
2859 	int ignore_crossmnt = 0;
2860 
2861 	dentry = lookup_one_len_unlocked(name, cd->rd_fhp->fh_dentry, namlen);
2862 	if (IS_ERR(dentry))
2863 		return nfserrno(PTR_ERR(dentry));
2864 	if (d_really_is_negative(dentry)) {
2865 		/*
2866 		 * we're not holding the i_mutex here, so there's
2867 		 * a window where this directory entry could have gone
2868 		 * away.
2869 		 */
2870 		dput(dentry);
2871 		return nfserr_noent;
2872 	}
2873 
2874 	exp_get(exp);
2875 	/*
2876 	 * In the case of a mountpoint, the client may be asking for
2877 	 * attributes that are only properties of the underlying filesystem
2878 	 * as opposed to the cross-mounted file system. In such a case,
2879 	 * we will not follow the cross mount and will fill the attribtutes
2880 	 * directly from the mountpoint dentry.
2881 	 */
2882 	if (nfsd_mountpoint(dentry, exp)) {
2883 		int err;
2884 
2885 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
2886 				&& !attributes_need_mount(cd->rd_bmval)) {
2887 			ignore_crossmnt = 1;
2888 			goto out_encode;
2889 		}
2890 		/*
2891 		 * Why the heck aren't we just using nfsd_lookup??
2892 		 * Different "."/".." handling?  Something else?
2893 		 * At least, add a comment here to explain....
2894 		 */
2895 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
2896 		if (err) {
2897 			nfserr = nfserrno(err);
2898 			goto out_put;
2899 		}
2900 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
2901 		if (nfserr)
2902 			goto out_put;
2903 
2904 	}
2905 out_encode:
2906 	nfserr = nfsd4_encode_fattr(xdr, NULL, exp, dentry, cd->rd_bmval,
2907 					cd->rd_rqstp, ignore_crossmnt);
2908 out_put:
2909 	dput(dentry);
2910 	exp_put(exp);
2911 	return nfserr;
2912 }
2913 
2914 static __be32 *
2915 nfsd4_encode_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
2916 {
2917 	__be32 *p;
2918 
2919 	p = xdr_reserve_space(xdr, 20);
2920 	if (!p)
2921 		return NULL;
2922 	*p++ = htonl(2);
2923 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
2924 	*p++ = htonl(0);			 /* bmval1 */
2925 
2926 	*p++ = htonl(4);     /* attribute length */
2927 	*p++ = nfserr;       /* no htonl */
2928 	return p;
2929 }
2930 
2931 static int
2932 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
2933 		    loff_t offset, u64 ino, unsigned int d_type)
2934 {
2935 	struct readdir_cd *ccd = ccdv;
2936 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
2937 	struct xdr_stream *xdr = cd->xdr;
2938 	int start_offset = xdr->buf->len;
2939 	int cookie_offset;
2940 	u32 name_and_cookie;
2941 	int entry_bytes;
2942 	__be32 nfserr = nfserr_toosmall;
2943 	__be64 wire_offset;
2944 	__be32 *p;
2945 
2946 	/* In nfsv4, "." and ".." never make it onto the wire.. */
2947 	if (name && isdotent(name, namlen)) {
2948 		cd->common.err = nfs_ok;
2949 		return 0;
2950 	}
2951 
2952 	if (cd->cookie_offset) {
2953 		wire_offset = cpu_to_be64(offset);
2954 		write_bytes_to_xdr_buf(xdr->buf, cd->cookie_offset,
2955 							&wire_offset, 8);
2956 	}
2957 
2958 	p = xdr_reserve_space(xdr, 4);
2959 	if (!p)
2960 		goto fail;
2961 	*p++ = xdr_one;                             /* mark entry present */
2962 	cookie_offset = xdr->buf->len;
2963 	p = xdr_reserve_space(xdr, 3*4 + namlen);
2964 	if (!p)
2965 		goto fail;
2966 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
2967 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
2968 
2969 	nfserr = nfsd4_encode_dirent_fattr(xdr, cd, name, namlen);
2970 	switch (nfserr) {
2971 	case nfs_ok:
2972 		break;
2973 	case nfserr_resource:
2974 		nfserr = nfserr_toosmall;
2975 		goto fail;
2976 	case nfserr_noent:
2977 		xdr_truncate_encode(xdr, start_offset);
2978 		goto skip_entry;
2979 	default:
2980 		/*
2981 		 * If the client requested the RDATTR_ERROR attribute,
2982 		 * we stuff the error code into this attribute
2983 		 * and continue.  If this attribute was not requested,
2984 		 * then in accordance with the spec, we fail the
2985 		 * entire READDIR operation(!)
2986 		 */
2987 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
2988 			goto fail;
2989 		p = nfsd4_encode_rdattr_error(xdr, nfserr);
2990 		if (p == NULL) {
2991 			nfserr = nfserr_toosmall;
2992 			goto fail;
2993 		}
2994 	}
2995 	nfserr = nfserr_toosmall;
2996 	entry_bytes = xdr->buf->len - start_offset;
2997 	if (entry_bytes > cd->rd_maxcount)
2998 		goto fail;
2999 	cd->rd_maxcount -= entry_bytes;
3000 	/*
3001 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so
3002 	 * let's always let through the first entry, at least:
3003 	 */
3004 	if (!cd->rd_dircount)
3005 		goto fail;
3006 	name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8;
3007 	if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
3008 		goto fail;
3009 	cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
3010 
3011 	cd->cookie_offset = cookie_offset;
3012 skip_entry:
3013 	cd->common.err = nfs_ok;
3014 	return 0;
3015 fail:
3016 	xdr_truncate_encode(xdr, start_offset);
3017 	cd->common.err = nfserr;
3018 	return -EINVAL;
3019 }
3020 
3021 static __be32
3022 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
3023 {
3024 	__be32 *p;
3025 
3026 	p = xdr_reserve_space(xdr, sizeof(stateid_t));
3027 	if (!p)
3028 		return nfserr_resource;
3029 	*p++ = cpu_to_be32(sid->si_generation);
3030 	p = xdr_encode_opaque_fixed(p, &sid->si_opaque,
3031 					sizeof(stateid_opaque_t));
3032 	return 0;
3033 }
3034 
3035 static __be32
3036 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
3037 {
3038 	struct xdr_stream *xdr = &resp->xdr;
3039 	__be32 *p;
3040 
3041 	if (!nfserr) {
3042 		p = xdr_reserve_space(xdr, 8);
3043 		if (!p)
3044 			return nfserr_resource;
3045 		*p++ = cpu_to_be32(access->ac_supported);
3046 		*p++ = cpu_to_be32(access->ac_resp_access);
3047 	}
3048 	return nfserr;
3049 }
3050 
3051 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
3052 {
3053 	struct xdr_stream *xdr = &resp->xdr;
3054 	__be32 *p;
3055 
3056 	if (!nfserr) {
3057 		p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 8);
3058 		if (!p)
3059 			return nfserr_resource;
3060 		p = xdr_encode_opaque_fixed(p, bcts->sessionid.data,
3061 						NFS4_MAX_SESSIONID_LEN);
3062 		*p++ = cpu_to_be32(bcts->dir);
3063 		/* Sorry, we do not yet support RDMA over 4.1: */
3064 		*p++ = cpu_to_be32(0);
3065 	}
3066 	return nfserr;
3067 }
3068 
3069 static __be32
3070 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
3071 {
3072 	struct xdr_stream *xdr = &resp->xdr;
3073 
3074 	if (!nfserr)
3075 		nfserr = nfsd4_encode_stateid(xdr, &close->cl_stateid);
3076 
3077 	return nfserr;
3078 }
3079 
3080 
3081 static __be32
3082 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
3083 {
3084 	struct xdr_stream *xdr = &resp->xdr;
3085 	__be32 *p;
3086 
3087 	if (!nfserr) {
3088 		p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3089 		if (!p)
3090 			return nfserr_resource;
3091 		p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
3092 						NFS4_VERIFIER_SIZE);
3093 	}
3094 	return nfserr;
3095 }
3096 
3097 static __be32
3098 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
3099 {
3100 	struct xdr_stream *xdr = &resp->xdr;
3101 	__be32 *p;
3102 
3103 	if (!nfserr) {
3104 		p = xdr_reserve_space(xdr, 20);
3105 		if (!p)
3106 			return nfserr_resource;
3107 		encode_cinfo(p, &create->cr_cinfo);
3108 		nfserr = nfsd4_encode_bitmap(xdr, create->cr_bmval[0],
3109 				create->cr_bmval[1], create->cr_bmval[2]);
3110 	}
3111 	return nfserr;
3112 }
3113 
3114 static __be32
3115 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
3116 {
3117 	struct svc_fh *fhp = getattr->ga_fhp;
3118 	struct xdr_stream *xdr = &resp->xdr;
3119 
3120 	if (nfserr)
3121 		return nfserr;
3122 
3123 	nfserr = nfsd4_encode_fattr(xdr, fhp, fhp->fh_export, fhp->fh_dentry,
3124 				    getattr->ga_bmval,
3125 				    resp->rqstp, 0);
3126 	return nfserr;
3127 }
3128 
3129 static __be32
3130 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
3131 {
3132 	struct xdr_stream *xdr = &resp->xdr;
3133 	struct svc_fh *fhp = *fhpp;
3134 	unsigned int len;
3135 	__be32 *p;
3136 
3137 	if (!nfserr) {
3138 		len = fhp->fh_handle.fh_size;
3139 		p = xdr_reserve_space(xdr, len + 4);
3140 		if (!p)
3141 			return nfserr_resource;
3142 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base, len);
3143 	}
3144 	return nfserr;
3145 }
3146 
3147 /*
3148 * Including all fields other than the name, a LOCK4denied structure requires
3149 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
3150 */
3151 static __be32
3152 nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld)
3153 {
3154 	struct xdr_netobj *conf = &ld->ld_owner;
3155 	__be32 *p;
3156 
3157 again:
3158 	p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len));
3159 	if (!p) {
3160 		/*
3161 		 * Don't fail to return the result just because we can't
3162 		 * return the conflicting open:
3163 		 */
3164 		if (conf->len) {
3165 			kfree(conf->data);
3166 			conf->len = 0;
3167 			conf->data = NULL;
3168 			goto again;
3169 		}
3170 		return nfserr_resource;
3171 	}
3172 	p = xdr_encode_hyper(p, ld->ld_start);
3173 	p = xdr_encode_hyper(p, ld->ld_length);
3174 	*p++ = cpu_to_be32(ld->ld_type);
3175 	if (conf->len) {
3176 		p = xdr_encode_opaque_fixed(p, &ld->ld_clientid, 8);
3177 		p = xdr_encode_opaque(p, conf->data, conf->len);
3178 		kfree(conf->data);
3179 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
3180 		p = xdr_encode_hyper(p, (u64)0); /* clientid */
3181 		*p++ = cpu_to_be32(0); /* length of owner name */
3182 	}
3183 	return nfserr_denied;
3184 }
3185 
3186 static __be32
3187 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
3188 {
3189 	struct xdr_stream *xdr = &resp->xdr;
3190 
3191 	if (!nfserr)
3192 		nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid);
3193 	else if (nfserr == nfserr_denied)
3194 		nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied);
3195 
3196 	return nfserr;
3197 }
3198 
3199 static __be32
3200 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
3201 {
3202 	struct xdr_stream *xdr = &resp->xdr;
3203 
3204 	if (nfserr == nfserr_denied)
3205 		nfsd4_encode_lock_denied(xdr, &lockt->lt_denied);
3206 	return nfserr;
3207 }
3208 
3209 static __be32
3210 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
3211 {
3212 	struct xdr_stream *xdr = &resp->xdr;
3213 
3214 	if (!nfserr)
3215 		nfserr = nfsd4_encode_stateid(xdr, &locku->lu_stateid);
3216 
3217 	return nfserr;
3218 }
3219 
3220 
3221 static __be32
3222 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
3223 {
3224 	struct xdr_stream *xdr = &resp->xdr;
3225 	__be32 *p;
3226 
3227 	if (!nfserr) {
3228 		p = xdr_reserve_space(xdr, 20);
3229 		if (!p)
3230 			return nfserr_resource;
3231 		p = encode_cinfo(p, &link->li_cinfo);
3232 	}
3233 	return nfserr;
3234 }
3235 
3236 
3237 static __be32
3238 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
3239 {
3240 	struct xdr_stream *xdr = &resp->xdr;
3241 	__be32 *p;
3242 
3243 	if (nfserr)
3244 		goto out;
3245 
3246 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
3247 	if (nfserr)
3248 		goto out;
3249 	p = xdr_reserve_space(xdr, 24);
3250 	if (!p)
3251 		return nfserr_resource;
3252 	p = encode_cinfo(p, &open->op_cinfo);
3253 	*p++ = cpu_to_be32(open->op_rflags);
3254 
3255 	nfserr = nfsd4_encode_bitmap(xdr, open->op_bmval[0], open->op_bmval[1],
3256 					open->op_bmval[2]);
3257 	if (nfserr)
3258 		goto out;
3259 
3260 	p = xdr_reserve_space(xdr, 4);
3261 	if (!p)
3262 		return nfserr_resource;
3263 
3264 	*p++ = cpu_to_be32(open->op_delegate_type);
3265 	switch (open->op_delegate_type) {
3266 	case NFS4_OPEN_DELEGATE_NONE:
3267 		break;
3268 	case NFS4_OPEN_DELEGATE_READ:
3269 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3270 		if (nfserr)
3271 			return nfserr;
3272 		p = xdr_reserve_space(xdr, 20);
3273 		if (!p)
3274 			return nfserr_resource;
3275 		*p++ = cpu_to_be32(open->op_recall);
3276 
3277 		/*
3278 		 * TODO: ACE's in delegations
3279 		 */
3280 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3281 		*p++ = cpu_to_be32(0);
3282 		*p++ = cpu_to_be32(0);
3283 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3284 		break;
3285 	case NFS4_OPEN_DELEGATE_WRITE:
3286 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3287 		if (nfserr)
3288 			return nfserr;
3289 		p = xdr_reserve_space(xdr, 32);
3290 		if (!p)
3291 			return nfserr_resource;
3292 		*p++ = cpu_to_be32(0);
3293 
3294 		/*
3295 		 * TODO: space_limit's in delegations
3296 		 */
3297 		*p++ = cpu_to_be32(NFS4_LIMIT_SIZE);
3298 		*p++ = cpu_to_be32(~(u32)0);
3299 		*p++ = cpu_to_be32(~(u32)0);
3300 
3301 		/*
3302 		 * TODO: ACE's in delegations
3303 		 */
3304 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3305 		*p++ = cpu_to_be32(0);
3306 		*p++ = cpu_to_be32(0);
3307 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3308 		break;
3309 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
3310 		switch (open->op_why_no_deleg) {
3311 		case WND4_CONTENTION:
3312 		case WND4_RESOURCE:
3313 			p = xdr_reserve_space(xdr, 8);
3314 			if (!p)
3315 				return nfserr_resource;
3316 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3317 			/* deleg signaling not supported yet: */
3318 			*p++ = cpu_to_be32(0);
3319 			break;
3320 		default:
3321 			p = xdr_reserve_space(xdr, 4);
3322 			if (!p)
3323 				return nfserr_resource;
3324 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3325 		}
3326 		break;
3327 	default:
3328 		BUG();
3329 	}
3330 	/* XXX save filehandle here */
3331 out:
3332 	return nfserr;
3333 }
3334 
3335 static __be32
3336 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
3337 {
3338 	struct xdr_stream *xdr = &resp->xdr;
3339 
3340 	if (!nfserr)
3341 		nfserr = nfsd4_encode_stateid(xdr, &oc->oc_resp_stateid);
3342 
3343 	return nfserr;
3344 }
3345 
3346 static __be32
3347 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
3348 {
3349 	struct xdr_stream *xdr = &resp->xdr;
3350 
3351 	if (!nfserr)
3352 		nfserr = nfsd4_encode_stateid(xdr, &od->od_stateid);
3353 
3354 	return nfserr;
3355 }
3356 
3357 static __be32 nfsd4_encode_splice_read(
3358 				struct nfsd4_compoundres *resp,
3359 				struct nfsd4_read *read,
3360 				struct file *file, unsigned long maxcount)
3361 {
3362 	struct xdr_stream *xdr = &resp->xdr;
3363 	struct xdr_buf *buf = xdr->buf;
3364 	u32 eof;
3365 	int space_left;
3366 	__be32 nfserr;
3367 	__be32 *p = xdr->p - 2;
3368 
3369 	/* Make sure there will be room for padding if needed */
3370 	if (xdr->end - xdr->p < 1)
3371 		return nfserr_resource;
3372 
3373 	nfserr = nfsd_splice_read(read->rd_rqstp, file,
3374 				  read->rd_offset, &maxcount);
3375 	if (nfserr) {
3376 		/*
3377 		 * nfsd_splice_actor may have already messed with the
3378 		 * page length; reset it so as not to confuse
3379 		 * xdr_truncate_encode:
3380 		 */
3381 		buf->page_len = 0;
3382 		return nfserr;
3383 	}
3384 
3385 	eof = (read->rd_offset + maxcount >=
3386 	       d_inode(read->rd_fhp->fh_dentry)->i_size);
3387 
3388 	*(p++) = htonl(eof);
3389 	*(p++) = htonl(maxcount);
3390 
3391 	buf->page_len = maxcount;
3392 	buf->len += maxcount;
3393 	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
3394 							/ PAGE_SIZE;
3395 
3396 	/* Use rest of head for padding and remaining ops: */
3397 	buf->tail[0].iov_base = xdr->p;
3398 	buf->tail[0].iov_len = 0;
3399 	xdr->iov = buf->tail;
3400 	if (maxcount&3) {
3401 		int pad = 4 - (maxcount&3);
3402 
3403 		*(xdr->p++) = 0;
3404 
3405 		buf->tail[0].iov_base += maxcount&3;
3406 		buf->tail[0].iov_len = pad;
3407 		buf->len += pad;
3408 	}
3409 
3410 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
3411 				buf->buflen - buf->len);
3412 	buf->buflen = buf->len + space_left;
3413 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
3414 
3415 	return 0;
3416 }
3417 
3418 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
3419 				 struct nfsd4_read *read,
3420 				 struct file *file, unsigned long maxcount)
3421 {
3422 	struct xdr_stream *xdr = &resp->xdr;
3423 	u32 eof;
3424 	int v;
3425 	int starting_len = xdr->buf->len - 8;
3426 	long len;
3427 	int thislen;
3428 	__be32 nfserr;
3429 	__be32 tmp;
3430 	__be32 *p;
3431 	u32 zzz = 0;
3432 	int pad;
3433 
3434 	len = maxcount;
3435 	v = 0;
3436 
3437 	thislen = min_t(long, len, ((void *)xdr->end - (void *)xdr->p));
3438 	p = xdr_reserve_space(xdr, (thislen+3)&~3);
3439 	WARN_ON_ONCE(!p);
3440 	resp->rqstp->rq_vec[v].iov_base = p;
3441 	resp->rqstp->rq_vec[v].iov_len = thislen;
3442 	v++;
3443 	len -= thislen;
3444 
3445 	while (len) {
3446 		thislen = min_t(long, len, PAGE_SIZE);
3447 		p = xdr_reserve_space(xdr, (thislen+3)&~3);
3448 		WARN_ON_ONCE(!p);
3449 		resp->rqstp->rq_vec[v].iov_base = p;
3450 		resp->rqstp->rq_vec[v].iov_len = thislen;
3451 		v++;
3452 		len -= thislen;
3453 	}
3454 	read->rd_vlen = v;
3455 
3456 	nfserr = nfsd_readv(file, read->rd_offset, resp->rqstp->rq_vec,
3457 			read->rd_vlen, &maxcount);
3458 	if (nfserr)
3459 		return nfserr;
3460 	xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3));
3461 
3462 	eof = (read->rd_offset + maxcount >=
3463 	       d_inode(read->rd_fhp->fh_dentry)->i_size);
3464 
3465 	tmp = htonl(eof);
3466 	write_bytes_to_xdr_buf(xdr->buf, starting_len    , &tmp, 4);
3467 	tmp = htonl(maxcount);
3468 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
3469 
3470 	pad = (maxcount&3) ? 4 - (maxcount&3) : 0;
3471 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 8 + maxcount,
3472 								&zzz, pad);
3473 	return 0;
3474 
3475 }
3476 
3477 static __be32
3478 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
3479 		  struct nfsd4_read *read)
3480 {
3481 	unsigned long maxcount;
3482 	struct xdr_stream *xdr = &resp->xdr;
3483 	struct file *file = read->rd_filp;
3484 	int starting_len = xdr->buf->len;
3485 	struct raparms *ra = NULL;
3486 	__be32 *p;
3487 
3488 	if (nfserr)
3489 		goto out;
3490 
3491 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
3492 	if (!p) {
3493 		WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
3494 		nfserr = nfserr_resource;
3495 		goto out;
3496 	}
3497 	if (resp->xdr.buf->page_len &&
3498 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
3499 		WARN_ON_ONCE(1);
3500 		nfserr = nfserr_resource;
3501 		goto out;
3502 	}
3503 	xdr_commit_encode(xdr);
3504 
3505 	maxcount = svc_max_payload(resp->rqstp);
3506 	maxcount = min_t(unsigned long, maxcount,
3507 			 (xdr->buf->buflen - xdr->buf->len));
3508 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
3509 
3510 	if (read->rd_tmp_file)
3511 		ra = nfsd_init_raparms(file);
3512 
3513 	if (file->f_op->splice_read &&
3514 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
3515 		nfserr = nfsd4_encode_splice_read(resp, read, file, maxcount);
3516 	else
3517 		nfserr = nfsd4_encode_readv(resp, read, file, maxcount);
3518 
3519 	if (ra)
3520 		nfsd_put_raparams(file, ra);
3521 
3522 	if (nfserr)
3523 		xdr_truncate_encode(xdr, starting_len);
3524 
3525 out:
3526 	if (file)
3527 		fput(file);
3528 	return nfserr;
3529 }
3530 
3531 static __be32
3532 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3533 {
3534 	int maxcount;
3535 	__be32 wire_count;
3536 	int zero = 0;
3537 	struct xdr_stream *xdr = &resp->xdr;
3538 	int length_offset = xdr->buf->len;
3539 	__be32 *p;
3540 
3541 	if (nfserr)
3542 		return nfserr;
3543 
3544 	p = xdr_reserve_space(xdr, 4);
3545 	if (!p)
3546 		return nfserr_resource;
3547 	maxcount = PAGE_SIZE;
3548 
3549 	p = xdr_reserve_space(xdr, maxcount);
3550 	if (!p)
3551 		return nfserr_resource;
3552 	/*
3553 	 * XXX: By default, the ->readlink() VFS op will truncate symlinks
3554 	 * if they would overflow the buffer.  Is this kosher in NFSv4?  If
3555 	 * not, one easy fix is: if ->readlink() precisely fills the buffer,
3556 	 * assume that truncation occurred, and return NFS4ERR_RESOURCE.
3557 	 */
3558 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
3559 						(char *)p, &maxcount);
3560 	if (nfserr == nfserr_isdir)
3561 		nfserr = nfserr_inval;
3562 	if (nfserr) {
3563 		xdr_truncate_encode(xdr, length_offset);
3564 		return nfserr;
3565 	}
3566 
3567 	wire_count = htonl(maxcount);
3568 	write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
3569 	xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
3570 	if (maxcount & 3)
3571 		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
3572 						&zero, 4 - (maxcount&3));
3573 	return 0;
3574 }
3575 
3576 static __be32
3577 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3578 {
3579 	int maxcount;
3580 	int bytes_left;
3581 	loff_t offset;
3582 	__be64 wire_offset;
3583 	struct xdr_stream *xdr = &resp->xdr;
3584 	int starting_len = xdr->buf->len;
3585 	__be32 *p;
3586 
3587 	if (nfserr)
3588 		return nfserr;
3589 
3590 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3591 	if (!p)
3592 		return nfserr_resource;
3593 
3594 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3595 	*p++ = cpu_to_be32(0);
3596 	*p++ = cpu_to_be32(0);
3597 	resp->xdr.buf->head[0].iov_len = ((char *)resp->xdr.p)
3598 				- (char *)resp->xdr.buf->head[0].iov_base;
3599 
3600 	/*
3601 	 * Number of bytes left for directory entries allowing for the
3602 	 * final 8 bytes of the readdir and a following failed op:
3603 	 */
3604 	bytes_left = xdr->buf->buflen - xdr->buf->len
3605 			- COMPOUND_ERR_SLACK_SPACE - 8;
3606 	if (bytes_left < 0) {
3607 		nfserr = nfserr_resource;
3608 		goto err_no_verf;
3609 	}
3610 	maxcount = min_t(u32, readdir->rd_maxcount, INT_MAX);
3611 	/*
3612 	 * Note the rfc defines rd_maxcount as the size of the
3613 	 * READDIR4resok structure, which includes the verifier above
3614 	 * and the 8 bytes encoded at the end of this function:
3615 	 */
3616 	if (maxcount < 16) {
3617 		nfserr = nfserr_toosmall;
3618 		goto err_no_verf;
3619 	}
3620 	maxcount = min_t(int, maxcount-16, bytes_left);
3621 
3622 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
3623 	if (!readdir->rd_dircount)
3624 		readdir->rd_dircount = INT_MAX;
3625 
3626 	readdir->xdr = xdr;
3627 	readdir->rd_maxcount = maxcount;
3628 	readdir->common.err = 0;
3629 	readdir->cookie_offset = 0;
3630 
3631 	offset = readdir->rd_cookie;
3632 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3633 			      &offset,
3634 			      &readdir->common, nfsd4_encode_dirent);
3635 	if (nfserr == nfs_ok &&
3636 	    readdir->common.err == nfserr_toosmall &&
3637 	    xdr->buf->len == starting_len + 8) {
3638 		/* nothing encoded; which limit did we hit?: */
3639 		if (maxcount - 16 < bytes_left)
3640 			/* It was the fault of rd_maxcount: */
3641 			nfserr = nfserr_toosmall;
3642 		else
3643 			/* We ran out of buffer space: */
3644 			nfserr = nfserr_resource;
3645 	}
3646 	if (nfserr)
3647 		goto err_no_verf;
3648 
3649 	if (readdir->cookie_offset) {
3650 		wire_offset = cpu_to_be64(offset);
3651 		write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset,
3652 							&wire_offset, 8);
3653 	}
3654 
3655 	p = xdr_reserve_space(xdr, 8);
3656 	if (!p) {
3657 		WARN_ON_ONCE(1);
3658 		goto err_no_verf;
3659 	}
3660 	*p++ = 0;	/* no more entries */
3661 	*p++ = htonl(readdir->common.err == nfserr_eof);
3662 
3663 	return 0;
3664 err_no_verf:
3665 	xdr_truncate_encode(xdr, starting_len);
3666 	return nfserr;
3667 }
3668 
3669 static __be32
3670 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3671 {
3672 	struct xdr_stream *xdr = &resp->xdr;
3673 	__be32 *p;
3674 
3675 	if (!nfserr) {
3676 		p = xdr_reserve_space(xdr, 20);
3677 		if (!p)
3678 			return nfserr_resource;
3679 		p = encode_cinfo(p, &remove->rm_cinfo);
3680 	}
3681 	return nfserr;
3682 }
3683 
3684 static __be32
3685 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3686 {
3687 	struct xdr_stream *xdr = &resp->xdr;
3688 	__be32 *p;
3689 
3690 	if (!nfserr) {
3691 		p = xdr_reserve_space(xdr, 40);
3692 		if (!p)
3693 			return nfserr_resource;
3694 		p = encode_cinfo(p, &rename->rn_sinfo);
3695 		p = encode_cinfo(p, &rename->rn_tinfo);
3696 	}
3697 	return nfserr;
3698 }
3699 
3700 static __be32
3701 nfsd4_do_encode_secinfo(struct xdr_stream *xdr,
3702 			 __be32 nfserr, struct svc_export *exp)
3703 {
3704 	u32 i, nflavs, supported;
3705 	struct exp_flavor_info *flavs;
3706 	struct exp_flavor_info def_flavs[2];
3707 	__be32 *p, *flavorsp;
3708 	static bool report = true;
3709 
3710 	if (nfserr)
3711 		goto out;
3712 	nfserr = nfserr_resource;
3713 	if (exp->ex_nflavors) {
3714 		flavs = exp->ex_flavors;
3715 		nflavs = exp->ex_nflavors;
3716 	} else { /* Handling of some defaults in absence of real secinfo: */
3717 		flavs = def_flavs;
3718 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3719 			nflavs = 2;
3720 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3721 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3722 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3723 			nflavs = 1;
3724 			flavs[0].pseudoflavor
3725 					= svcauth_gss_flavor(exp->ex_client);
3726 		} else {
3727 			nflavs = 1;
3728 			flavs[0].pseudoflavor
3729 					= exp->ex_client->flavour->flavour;
3730 		}
3731 	}
3732 
3733 	supported = 0;
3734 	p = xdr_reserve_space(xdr, 4);
3735 	if (!p)
3736 		goto out;
3737 	flavorsp = p++;		/* to be backfilled later */
3738 
3739 	for (i = 0; i < nflavs; i++) {
3740 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
3741 		struct rpcsec_gss_info info;
3742 
3743 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
3744 			supported++;
3745 			p = xdr_reserve_space(xdr, 4 + 4 +
3746 					      XDR_LEN(info.oid.len) + 4 + 4);
3747 			if (!p)
3748 				goto out;
3749 			*p++ = cpu_to_be32(RPC_AUTH_GSS);
3750 			p = xdr_encode_opaque(p,  info.oid.data, info.oid.len);
3751 			*p++ = cpu_to_be32(info.qop);
3752 			*p++ = cpu_to_be32(info.service);
3753 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
3754 			supported++;
3755 			p = xdr_reserve_space(xdr, 4);
3756 			if (!p)
3757 				goto out;
3758 			*p++ = cpu_to_be32(pf);
3759 		} else {
3760 			if (report)
3761 				pr_warn("NFS: SECINFO: security flavor %u "
3762 					"is not supported\n", pf);
3763 		}
3764 	}
3765 
3766 	if (nflavs != supported)
3767 		report = false;
3768 	*flavorsp = htonl(supported);
3769 	nfserr = 0;
3770 out:
3771 	if (exp)
3772 		exp_put(exp);
3773 	return nfserr;
3774 }
3775 
3776 static __be32
3777 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3778 		     struct nfsd4_secinfo *secinfo)
3779 {
3780 	struct xdr_stream *xdr = &resp->xdr;
3781 
3782 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->si_exp);
3783 }
3784 
3785 static __be32
3786 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3787 		     struct nfsd4_secinfo_no_name *secinfo)
3788 {
3789 	struct xdr_stream *xdr = &resp->xdr;
3790 
3791 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->sin_exp);
3792 }
3793 
3794 /*
3795  * The SETATTR encode routine is special -- it always encodes a bitmap,
3796  * regardless of the error status.
3797  */
3798 static __be32
3799 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3800 {
3801 	struct xdr_stream *xdr = &resp->xdr;
3802 	__be32 *p;
3803 
3804 	p = xdr_reserve_space(xdr, 16);
3805 	if (!p)
3806 		return nfserr_resource;
3807 	if (nfserr) {
3808 		*p++ = cpu_to_be32(3);
3809 		*p++ = cpu_to_be32(0);
3810 		*p++ = cpu_to_be32(0);
3811 		*p++ = cpu_to_be32(0);
3812 	}
3813 	else {
3814 		*p++ = cpu_to_be32(3);
3815 		*p++ = cpu_to_be32(setattr->sa_bmval[0]);
3816 		*p++ = cpu_to_be32(setattr->sa_bmval[1]);
3817 		*p++ = cpu_to_be32(setattr->sa_bmval[2]);
3818 	}
3819 	return nfserr;
3820 }
3821 
3822 static __be32
3823 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3824 {
3825 	struct xdr_stream *xdr = &resp->xdr;
3826 	__be32 *p;
3827 
3828 	if (!nfserr) {
3829 		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
3830 		if (!p)
3831 			return nfserr_resource;
3832 		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
3833 		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
3834 						NFS4_VERIFIER_SIZE);
3835 	}
3836 	else if (nfserr == nfserr_clid_inuse) {
3837 		p = xdr_reserve_space(xdr, 8);
3838 		if (!p)
3839 			return nfserr_resource;
3840 		*p++ = cpu_to_be32(0);
3841 		*p++ = cpu_to_be32(0);
3842 	}
3843 	return nfserr;
3844 }
3845 
3846 static __be32
3847 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3848 {
3849 	struct xdr_stream *xdr = &resp->xdr;
3850 	__be32 *p;
3851 
3852 	if (!nfserr) {
3853 		p = xdr_reserve_space(xdr, 16);
3854 		if (!p)
3855 			return nfserr_resource;
3856 		*p++ = cpu_to_be32(write->wr_bytes_written);
3857 		*p++ = cpu_to_be32(write->wr_how_written);
3858 		p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
3859 							NFS4_VERIFIER_SIZE);
3860 	}
3861 	return nfserr;
3862 }
3863 
3864 static const u32 nfs4_minimal_spo_must_enforce[2] = {
3865 	[1] = 1 << (OP_BIND_CONN_TO_SESSION - 32) |
3866 	      1 << (OP_EXCHANGE_ID - 32) |
3867 	      1 << (OP_CREATE_SESSION - 32) |
3868 	      1 << (OP_DESTROY_SESSION - 32) |
3869 	      1 << (OP_DESTROY_CLIENTID - 32)
3870 };
3871 
3872 static __be32
3873 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
3874 			 struct nfsd4_exchange_id *exid)
3875 {
3876 	struct xdr_stream *xdr = &resp->xdr;
3877 	__be32 *p;
3878 	char *major_id;
3879 	char *server_scope;
3880 	int major_id_sz;
3881 	int server_scope_sz;
3882 	uint64_t minor_id = 0;
3883 
3884 	if (nfserr)
3885 		return nfserr;
3886 
3887 	major_id = utsname()->nodename;
3888 	major_id_sz = strlen(major_id);
3889 	server_scope = utsname()->nodename;
3890 	server_scope_sz = strlen(server_scope);
3891 
3892 	p = xdr_reserve_space(xdr,
3893 		8 /* eir_clientid */ +
3894 		4 /* eir_sequenceid */ +
3895 		4 /* eir_flags */ +
3896 		4 /* spr_how */);
3897 	if (!p)
3898 		return nfserr_resource;
3899 
3900 	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
3901 	*p++ = cpu_to_be32(exid->seqid);
3902 	*p++ = cpu_to_be32(exid->flags);
3903 
3904 	*p++ = cpu_to_be32(exid->spa_how);
3905 
3906 	switch (exid->spa_how) {
3907 	case SP4_NONE:
3908 		break;
3909 	case SP4_MACH_CRED:
3910 		/* spo_must_enforce, spo_must_allow */
3911 		p = xdr_reserve_space(xdr, 16);
3912 		if (!p)
3913 			return nfserr_resource;
3914 
3915 		/* spo_must_enforce bitmap: */
3916 		*p++ = cpu_to_be32(2);
3917 		*p++ = cpu_to_be32(nfs4_minimal_spo_must_enforce[0]);
3918 		*p++ = cpu_to_be32(nfs4_minimal_spo_must_enforce[1]);
3919 		/* empty spo_must_allow bitmap: */
3920 		*p++ = cpu_to_be32(0);
3921 
3922 		break;
3923 	default:
3924 		WARN_ON_ONCE(1);
3925 	}
3926 
3927 	p = xdr_reserve_space(xdr,
3928 		8 /* so_minor_id */ +
3929 		4 /* so_major_id.len */ +
3930 		(XDR_QUADLEN(major_id_sz) * 4) +
3931 		4 /* eir_server_scope.len */ +
3932 		(XDR_QUADLEN(server_scope_sz) * 4) +
3933 		4 /* eir_server_impl_id.count (0) */);
3934 	if (!p)
3935 		return nfserr_resource;
3936 
3937 	/* The server_owner struct */
3938 	p = xdr_encode_hyper(p, minor_id);      /* Minor id */
3939 	/* major id */
3940 	p = xdr_encode_opaque(p, major_id, major_id_sz);
3941 
3942 	/* Server scope */
3943 	p = xdr_encode_opaque(p, server_scope, server_scope_sz);
3944 
3945 	/* Implementation id */
3946 	*p++ = cpu_to_be32(0);	/* zero length nfs_impl_id4 array */
3947 	return 0;
3948 }
3949 
3950 static __be32
3951 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
3952 			    struct nfsd4_create_session *sess)
3953 {
3954 	struct xdr_stream *xdr = &resp->xdr;
3955 	__be32 *p;
3956 
3957 	if (nfserr)
3958 		return nfserr;
3959 
3960 	p = xdr_reserve_space(xdr, 24);
3961 	if (!p)
3962 		return nfserr_resource;
3963 	p = xdr_encode_opaque_fixed(p, sess->sessionid.data,
3964 					NFS4_MAX_SESSIONID_LEN);
3965 	*p++ = cpu_to_be32(sess->seqid);
3966 	*p++ = cpu_to_be32(sess->flags);
3967 
3968 	p = xdr_reserve_space(xdr, 28);
3969 	if (!p)
3970 		return nfserr_resource;
3971 	*p++ = cpu_to_be32(0); /* headerpadsz */
3972 	*p++ = cpu_to_be32(sess->fore_channel.maxreq_sz);
3973 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_sz);
3974 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_cached);
3975 	*p++ = cpu_to_be32(sess->fore_channel.maxops);
3976 	*p++ = cpu_to_be32(sess->fore_channel.maxreqs);
3977 	*p++ = cpu_to_be32(sess->fore_channel.nr_rdma_attrs);
3978 
3979 	if (sess->fore_channel.nr_rdma_attrs) {
3980 		p = xdr_reserve_space(xdr, 4);
3981 		if (!p)
3982 			return nfserr_resource;
3983 		*p++ = cpu_to_be32(sess->fore_channel.rdma_attrs);
3984 	}
3985 
3986 	p = xdr_reserve_space(xdr, 28);
3987 	if (!p)
3988 		return nfserr_resource;
3989 	*p++ = cpu_to_be32(0); /* headerpadsz */
3990 	*p++ = cpu_to_be32(sess->back_channel.maxreq_sz);
3991 	*p++ = cpu_to_be32(sess->back_channel.maxresp_sz);
3992 	*p++ = cpu_to_be32(sess->back_channel.maxresp_cached);
3993 	*p++ = cpu_to_be32(sess->back_channel.maxops);
3994 	*p++ = cpu_to_be32(sess->back_channel.maxreqs);
3995 	*p++ = cpu_to_be32(sess->back_channel.nr_rdma_attrs);
3996 
3997 	if (sess->back_channel.nr_rdma_attrs) {
3998 		p = xdr_reserve_space(xdr, 4);
3999 		if (!p)
4000 			return nfserr_resource;
4001 		*p++ = cpu_to_be32(sess->back_channel.rdma_attrs);
4002 	}
4003 	return 0;
4004 }
4005 
4006 static __be32
4007 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
4008 		      struct nfsd4_sequence *seq)
4009 {
4010 	struct xdr_stream *xdr = &resp->xdr;
4011 	__be32 *p;
4012 
4013 	if (nfserr)
4014 		return nfserr;
4015 
4016 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 20);
4017 	if (!p)
4018 		return nfserr_resource;
4019 	p = xdr_encode_opaque_fixed(p, seq->sessionid.data,
4020 					NFS4_MAX_SESSIONID_LEN);
4021 	*p++ = cpu_to_be32(seq->seqid);
4022 	*p++ = cpu_to_be32(seq->slotid);
4023 	/* Note slotid's are numbered from zero: */
4024 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_highest_slotid */
4025 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_target_highest_slotid */
4026 	*p++ = cpu_to_be32(seq->status_flags);
4027 
4028 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
4029 	return 0;
4030 }
4031 
4032 static __be32
4033 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
4034 			  struct nfsd4_test_stateid *test_stateid)
4035 {
4036 	struct xdr_stream *xdr = &resp->xdr;
4037 	struct nfsd4_test_stateid_id *stateid, *next;
4038 	__be32 *p;
4039 
4040 	if (nfserr)
4041 		return nfserr;
4042 
4043 	p = xdr_reserve_space(xdr, 4 + (4 * test_stateid->ts_num_ids));
4044 	if (!p)
4045 		return nfserr_resource;
4046 	*p++ = htonl(test_stateid->ts_num_ids);
4047 
4048 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
4049 		*p++ = stateid->ts_id_status;
4050 	}
4051 
4052 	return nfserr;
4053 }
4054 
4055 #ifdef CONFIG_NFSD_PNFS
4056 static __be32
4057 nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
4058 		struct nfsd4_getdeviceinfo *gdev)
4059 {
4060 	struct xdr_stream *xdr = &resp->xdr;
4061 	const struct nfsd4_layout_ops *ops =
4062 		nfsd4_layout_ops[gdev->gd_layout_type];
4063 	u32 starting_len = xdr->buf->len, needed_len;
4064 	__be32 *p;
4065 
4066 	dprintk("%s: err %d\n", __func__, nfserr);
4067 	if (nfserr)
4068 		goto out;
4069 
4070 	nfserr = nfserr_resource;
4071 	p = xdr_reserve_space(xdr, 4);
4072 	if (!p)
4073 		goto out;
4074 
4075 	*p++ = cpu_to_be32(gdev->gd_layout_type);
4076 
4077 	/* If maxcount is 0 then just update notifications */
4078 	if (gdev->gd_maxcount != 0) {
4079 		nfserr = ops->encode_getdeviceinfo(xdr, gdev);
4080 		if (nfserr) {
4081 			/*
4082 			 * We don't bother to burden the layout drivers with
4083 			 * enforcing gd_maxcount, just tell the client to
4084 			 * come back with a bigger buffer if it's not enough.
4085 			 */
4086 			if (xdr->buf->len + 4 > gdev->gd_maxcount)
4087 				goto toosmall;
4088 			goto out;
4089 		}
4090 	}
4091 
4092 	nfserr = nfserr_resource;
4093 	if (gdev->gd_notify_types) {
4094 		p = xdr_reserve_space(xdr, 4 + 4);
4095 		if (!p)
4096 			goto out;
4097 		*p++ = cpu_to_be32(1);			/* bitmap length */
4098 		*p++ = cpu_to_be32(gdev->gd_notify_types);
4099 	} else {
4100 		p = xdr_reserve_space(xdr, 4);
4101 		if (!p)
4102 			goto out;
4103 		*p++ = 0;
4104 	}
4105 
4106 	nfserr = 0;
4107 out:
4108 	kfree(gdev->gd_device);
4109 	dprintk("%s: done: %d\n", __func__, be32_to_cpu(nfserr));
4110 	return nfserr;
4111 
4112 toosmall:
4113 	dprintk("%s: maxcount too small\n", __func__);
4114 	needed_len = xdr->buf->len + 4 /* notifications */;
4115 	xdr_truncate_encode(xdr, starting_len);
4116 	p = xdr_reserve_space(xdr, 4);
4117 	if (!p) {
4118 		nfserr = nfserr_resource;
4119 	} else {
4120 		*p++ = cpu_to_be32(needed_len);
4121 		nfserr = nfserr_toosmall;
4122 	}
4123 	goto out;
4124 }
4125 
4126 static __be32
4127 nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr,
4128 		struct nfsd4_layoutget *lgp)
4129 {
4130 	struct xdr_stream *xdr = &resp->xdr;
4131 	const struct nfsd4_layout_ops *ops =
4132 		nfsd4_layout_ops[lgp->lg_layout_type];
4133 	__be32 *p;
4134 
4135 	dprintk("%s: err %d\n", __func__, nfserr);
4136 	if (nfserr)
4137 		goto out;
4138 
4139 	nfserr = nfserr_resource;
4140 	p = xdr_reserve_space(xdr, 36 + sizeof(stateid_opaque_t));
4141 	if (!p)
4142 		goto out;
4143 
4144 	*p++ = cpu_to_be32(1);	/* we always set return-on-close */
4145 	*p++ = cpu_to_be32(lgp->lg_sid.si_generation);
4146 	p = xdr_encode_opaque_fixed(p, &lgp->lg_sid.si_opaque,
4147 				    sizeof(stateid_opaque_t));
4148 
4149 	*p++ = cpu_to_be32(1);	/* we always return a single layout */
4150 	p = xdr_encode_hyper(p, lgp->lg_seg.offset);
4151 	p = xdr_encode_hyper(p, lgp->lg_seg.length);
4152 	*p++ = cpu_to_be32(lgp->lg_seg.iomode);
4153 	*p++ = cpu_to_be32(lgp->lg_layout_type);
4154 
4155 	nfserr = ops->encode_layoutget(xdr, lgp);
4156 out:
4157 	kfree(lgp->lg_content);
4158 	return nfserr;
4159 }
4160 
4161 static __be32
4162 nfsd4_encode_layoutcommit(struct nfsd4_compoundres *resp, __be32 nfserr,
4163 			  struct nfsd4_layoutcommit *lcp)
4164 {
4165 	struct xdr_stream *xdr = &resp->xdr;
4166 	__be32 *p;
4167 
4168 	if (nfserr)
4169 		return nfserr;
4170 
4171 	p = xdr_reserve_space(xdr, 4);
4172 	if (!p)
4173 		return nfserr_resource;
4174 	*p++ = cpu_to_be32(lcp->lc_size_chg);
4175 	if (lcp->lc_size_chg) {
4176 		p = xdr_reserve_space(xdr, 8);
4177 		if (!p)
4178 			return nfserr_resource;
4179 		p = xdr_encode_hyper(p, lcp->lc_newsize);
4180 	}
4181 
4182 	return nfs_ok;
4183 }
4184 
4185 static __be32
4186 nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
4187 		struct nfsd4_layoutreturn *lrp)
4188 {
4189 	struct xdr_stream *xdr = &resp->xdr;
4190 	__be32 *p;
4191 
4192 	if (nfserr)
4193 		return nfserr;
4194 
4195 	p = xdr_reserve_space(xdr, 4);
4196 	if (!p)
4197 		return nfserr_resource;
4198 	*p++ = cpu_to_be32(lrp->lrs_present);
4199 	if (lrp->lrs_present)
4200 		return nfsd4_encode_stateid(xdr, &lrp->lr_sid);
4201 	return nfs_ok;
4202 }
4203 #endif /* CONFIG_NFSD_PNFS */
4204 
4205 static __be32
4206 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
4207 		  struct nfsd4_seek *seek)
4208 {
4209 	__be32 *p;
4210 
4211 	if (nfserr)
4212 		return nfserr;
4213 
4214 	p = xdr_reserve_space(&resp->xdr, 4 + 8);
4215 	*p++ = cpu_to_be32(seek->seek_eof);
4216 	p = xdr_encode_hyper(p, seek->seek_pos);
4217 
4218 	return nfserr;
4219 }
4220 
4221 static __be32
4222 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
4223 {
4224 	return nfserr;
4225 }
4226 
4227 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
4228 
4229 /*
4230  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
4231  * since we don't need to filter out obsolete ops as this is
4232  * done in the decoding phase.
4233  */
4234 static nfsd4_enc nfsd4_enc_ops[] = {
4235 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
4236 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
4237 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
4238 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
4239 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
4240 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4241 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
4242 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
4243 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
4244 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
4245 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
4246 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
4247 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
4248 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
4249 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4250 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
4251 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
4252 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
4253 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
4254 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4255 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
4256 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4257 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
4258 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
4259 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
4260 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
4261 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
4262 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
4263 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
4264 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
4265 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
4266 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
4267 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
4268 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
4269 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4270 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
4271 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
4272 
4273 	/* NFSv4.1 operations */
4274 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
4275 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
4276 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
4277 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
4278 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
4279 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
4280 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4281 #ifdef CONFIG_NFSD_PNFS
4282 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_getdeviceinfo,
4283 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4284 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_layoutcommit,
4285 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_layoutget,
4286 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_layoutreturn,
4287 #else
4288 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
4289 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4290 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
4291 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
4292 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4293 #endif
4294 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
4295 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
4296 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
4297 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
4298 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4299 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
4300 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
4301 
4302 	/* NFSv4.2 operations */
4303 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4304 	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_noop,
4305 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
4306 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4307 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
4308 	[OP_LAYOUTERROR]	= (nfsd4_enc)nfsd4_encode_noop,
4309 	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,
4310 	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,
4311 	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_noop,
4312 	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_noop,
4313 	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,
4314 	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,
4315 	[OP_CLONE]		= (nfsd4_enc)nfsd4_encode_noop,
4316 };
4317 
4318 /*
4319  * Calculate whether we still have space to encode repsize bytes.
4320  * There are two considerations:
4321  *     - For NFS versions >=4.1, the size of the reply must stay within
4322  *       session limits
4323  *     - For all NFS versions, we must stay within limited preallocated
4324  *       buffer space.
4325  *
4326  * This is called before the operation is processed, so can only provide
4327  * an upper estimate.  For some nonidempotent operations (such as
4328  * getattr), it's not necessarily a problem if that estimate is wrong,
4329  * as we can fail it after processing without significant side effects.
4330  */
4331 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
4332 {
4333 	struct xdr_buf *buf = &resp->rqstp->rq_res;
4334 	struct nfsd4_slot *slot = resp->cstate.slot;
4335 
4336 	if (buf->len + respsize <= buf->buflen)
4337 		return nfs_ok;
4338 	if (!nfsd4_has_session(&resp->cstate))
4339 		return nfserr_resource;
4340 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
4341 		WARN_ON_ONCE(1);
4342 		return nfserr_rep_too_big_to_cache;
4343 	}
4344 	return nfserr_rep_too_big;
4345 }
4346 
4347 void
4348 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
4349 {
4350 	struct xdr_stream *xdr = &resp->xdr;
4351 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
4352 	struct svc_rqst *rqstp = resp->rqstp;
4353 	int post_err_offset;
4354 	nfsd4_enc encoder;
4355 	__be32 *p;
4356 
4357 	p = xdr_reserve_space(xdr, 8);
4358 	if (!p) {
4359 		WARN_ON_ONCE(1);
4360 		return;
4361 	}
4362 	*p++ = cpu_to_be32(op->opnum);
4363 	post_err_offset = xdr->buf->len;
4364 
4365 	if (op->opnum == OP_ILLEGAL)
4366 		goto status;
4367 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
4368 	       !nfsd4_enc_ops[op->opnum]);
4369 	encoder = nfsd4_enc_ops[op->opnum];
4370 	op->status = encoder(resp, op->status, &op->u);
4371 	xdr_commit_encode(xdr);
4372 
4373 	/* nfsd4_check_resp_size guarantees enough room for error status */
4374 	if (!op->status) {
4375 		int space_needed = 0;
4376 		if (!nfsd4_last_compound_op(rqstp))
4377 			space_needed = COMPOUND_ERR_SLACK_SPACE;
4378 		op->status = nfsd4_check_resp_size(resp, space_needed);
4379 	}
4380 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
4381 		struct nfsd4_slot *slot = resp->cstate.slot;
4382 
4383 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
4384 			op->status = nfserr_rep_too_big_to_cache;
4385 		else
4386 			op->status = nfserr_rep_too_big;
4387 	}
4388 	if (op->status == nfserr_resource ||
4389 	    op->status == nfserr_rep_too_big ||
4390 	    op->status == nfserr_rep_too_big_to_cache) {
4391 		/*
4392 		 * The operation may have already been encoded or
4393 		 * partially encoded.  No op returns anything additional
4394 		 * in the case of one of these three errors, so we can
4395 		 * just truncate back to after the status.  But it's a
4396 		 * bug if we had to do this on a non-idempotent op:
4397 		 */
4398 		warn_on_nonidempotent_op(op);
4399 		xdr_truncate_encode(xdr, post_err_offset);
4400 	}
4401 	if (so) {
4402 		int len = xdr->buf->len - post_err_offset;
4403 
4404 		so->so_replay.rp_status = op->status;
4405 		so->so_replay.rp_buflen = len;
4406 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
4407 						so->so_replay.rp_buf, len);
4408 	}
4409 status:
4410 	/* Note that op->status is already in network byte order: */
4411 	write_bytes_to_xdr_buf(xdr->buf, post_err_offset - 4, &op->status, 4);
4412 }
4413 
4414 /*
4415  * Encode the reply stored in the stateowner reply cache
4416  *
4417  * XDR note: do not encode rp->rp_buflen: the buffer contains the
4418  * previously sent already encoded operation.
4419  */
4420 void
4421 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
4422 {
4423 	__be32 *p;
4424 	struct nfs4_replay *rp = op->replay;
4425 
4426 	BUG_ON(!rp);
4427 
4428 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
4429 	if (!p) {
4430 		WARN_ON_ONCE(1);
4431 		return;
4432 	}
4433 	*p++ = cpu_to_be32(op->opnum);
4434 	*p++ = rp->rp_status;  /* already xdr'ed */
4435 
4436 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
4437 }
4438 
4439 int
4440 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
4441 {
4442         return xdr_ressize_check(rqstp, p);
4443 }
4444 
4445 int nfsd4_release_compoundargs(void *rq, __be32 *p, void *resp)
4446 {
4447 	struct svc_rqst *rqstp = rq;
4448 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4449 
4450 	if (args->ops != args->iops) {
4451 		kfree(args->ops);
4452 		args->ops = args->iops;
4453 	}
4454 	kfree(args->tmpp);
4455 	args->tmpp = NULL;
4456 	while (args->to_free) {
4457 		struct svcxdr_tmpbuf *tb = args->to_free;
4458 		args->to_free = tb->next;
4459 		kfree(tb);
4460 	}
4461 	return 1;
4462 }
4463 
4464 int
4465 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundargs *args)
4466 {
4467 	if (rqstp->rq_arg.head[0].iov_len % 4) {
4468 		/* client is nuts */
4469 		dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)",
4470 			__func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid));
4471 		return 0;
4472 	}
4473 	args->p = p;
4474 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
4475 	args->pagelist = rqstp->rq_arg.pages;
4476 	args->pagelen = rqstp->rq_arg.page_len;
4477 	args->tmpp = NULL;
4478 	args->to_free = NULL;
4479 	args->ops = args->iops;
4480 	args->rqstp = rqstp;
4481 
4482 	return !nfsd4_decode_compound(args);
4483 }
4484 
4485 int
4486 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundres *resp)
4487 {
4488 	/*
4489 	 * All that remains is to write the tag and operation count...
4490 	 */
4491 	struct xdr_buf *buf = resp->xdr.buf;
4492 
4493 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
4494 				 buf->tail[0].iov_len);
4495 
4496 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
4497 
4498 	p = resp->tagp;
4499 	*p++ = htonl(resp->taglen);
4500 	memcpy(p, resp->tag, resp->taglen);
4501 	p += XDR_QUADLEN(resp->taglen);
4502 	*p++ = htonl(resp->opcnt);
4503 
4504 	nfsd4_sequence_done(resp);
4505 	return 1;
4506 }
4507 
4508 /*
4509  * Local variables:
4510  *  c-basic-offset: 8
4511  * End:
4512  */
4513