xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision bc5aa3a0)
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);
1076 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1077 	READ_BUF(4);
1078 	rename->rn_tnamelen = be32_to_cpup(p++);
1079 	READ_BUF(rename->rn_tnamelen);
1080 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1081 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1082 		return status;
1083 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1084 		return status;
1085 
1086 	DECODE_TAIL;
1087 }
1088 
1089 static __be32
1090 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1091 {
1092 	DECODE_HEAD;
1093 
1094 	if (argp->minorversion >= 1)
1095 		return nfserr_notsupp;
1096 
1097 	READ_BUF(sizeof(clientid_t));
1098 	COPYMEM(clientid, sizeof(clientid_t));
1099 
1100 	DECODE_TAIL;
1101 }
1102 
1103 static __be32
1104 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1105 		     struct nfsd4_secinfo *secinfo)
1106 {
1107 	DECODE_HEAD;
1108 
1109 	READ_BUF(4);
1110 	secinfo->si_namelen = be32_to_cpup(p++);
1111 	READ_BUF(secinfo->si_namelen);
1112 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1113 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1114 	if (status)
1115 		return status;
1116 	DECODE_TAIL;
1117 }
1118 
1119 static __be32
1120 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1121 		     struct nfsd4_secinfo_no_name *sin)
1122 {
1123 	DECODE_HEAD;
1124 
1125 	READ_BUF(4);
1126 	sin->sin_style = be32_to_cpup(p++);
1127 	DECODE_TAIL;
1128 }
1129 
1130 static __be32
1131 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1132 {
1133 	__be32 status;
1134 
1135 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1136 	if (status)
1137 		return status;
1138 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1139 				  &setattr->sa_acl, &setattr->sa_label);
1140 }
1141 
1142 static __be32
1143 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1144 {
1145 	DECODE_HEAD;
1146 
1147 	if (argp->minorversion >= 1)
1148 		return nfserr_notsupp;
1149 
1150 	READ_BUF(NFS4_VERIFIER_SIZE);
1151 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1152 
1153 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1154 	if (status)
1155 		return nfserr_bad_xdr;
1156 	READ_BUF(8);
1157 	setclientid->se_callback_prog = be32_to_cpup(p++);
1158 	setclientid->se_callback_netid_len = be32_to_cpup(p++);
1159 	READ_BUF(setclientid->se_callback_netid_len);
1160 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1161 	READ_BUF(4);
1162 	setclientid->se_callback_addr_len = be32_to_cpup(p++);
1163 
1164 	READ_BUF(setclientid->se_callback_addr_len);
1165 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1166 	READ_BUF(4);
1167 	setclientid->se_callback_ident = be32_to_cpup(p++);
1168 
1169 	DECODE_TAIL;
1170 }
1171 
1172 static __be32
1173 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1174 {
1175 	DECODE_HEAD;
1176 
1177 	if (argp->minorversion >= 1)
1178 		return nfserr_notsupp;
1179 
1180 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1181 	COPYMEM(&scd_c->sc_clientid, 8);
1182 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1183 
1184 	DECODE_TAIL;
1185 }
1186 
1187 /* Also used for NVERIFY */
1188 static __be32
1189 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1190 {
1191 	DECODE_HEAD;
1192 
1193 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1194 		goto out;
1195 
1196 	/* For convenience's sake, we compare raw xdr'd attributes in
1197 	 * nfsd4_proc_verify */
1198 
1199 	READ_BUF(4);
1200 	verify->ve_attrlen = be32_to_cpup(p++);
1201 	READ_BUF(verify->ve_attrlen);
1202 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1203 
1204 	DECODE_TAIL;
1205 }
1206 
1207 static __be32
1208 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1209 {
1210 	int avail;
1211 	int len;
1212 	DECODE_HEAD;
1213 
1214 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1215 	if (status)
1216 		return status;
1217 	READ_BUF(16);
1218 	p = xdr_decode_hyper(p, &write->wr_offset);
1219 	write->wr_stable_how = be32_to_cpup(p++);
1220 	if (write->wr_stable_how > 2)
1221 		goto xdr_error;
1222 	write->wr_buflen = be32_to_cpup(p++);
1223 
1224 	/* Sorry .. no magic macros for this.. *
1225 	 * READ_BUF(write->wr_buflen);
1226 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1227 	 */
1228 	avail = (char*)argp->end - (char*)argp->p;
1229 	if (avail + argp->pagelen < write->wr_buflen) {
1230 		dprintk("NFSD: xdr error (%s:%d)\n",
1231 				__FILE__, __LINE__);
1232 		goto xdr_error;
1233 	}
1234 	write->wr_head.iov_base = p;
1235 	write->wr_head.iov_len = avail;
1236 	write->wr_pagelist = argp->pagelist;
1237 
1238 	len = XDR_QUADLEN(write->wr_buflen) << 2;
1239 	if (len >= avail) {
1240 		int pages;
1241 
1242 		len -= avail;
1243 
1244 		pages = len >> PAGE_SHIFT;
1245 		argp->pagelist += pages;
1246 		argp->pagelen -= pages * PAGE_SIZE;
1247 		len -= pages * PAGE_SIZE;
1248 
1249 		argp->p = (__be32 *)page_address(argp->pagelist[0]);
1250 		argp->pagelist++;
1251 		argp->end = argp->p + XDR_QUADLEN(PAGE_SIZE);
1252 	}
1253 	argp->p += XDR_QUADLEN(len);
1254 
1255 	DECODE_TAIL;
1256 }
1257 
1258 static __be32
1259 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1260 {
1261 	DECODE_HEAD;
1262 
1263 	if (argp->minorversion >= 1)
1264 		return nfserr_notsupp;
1265 
1266 	READ_BUF(12);
1267 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1268 	rlockowner->rl_owner.len = be32_to_cpup(p++);
1269 	READ_BUF(rlockowner->rl_owner.len);
1270 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1271 
1272 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1273 		return nfserr_inval;
1274 	DECODE_TAIL;
1275 }
1276 
1277 static __be32
1278 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1279 			 struct nfsd4_exchange_id *exid)
1280 {
1281 	int dummy, tmp;
1282 	DECODE_HEAD;
1283 
1284 	READ_BUF(NFS4_VERIFIER_SIZE);
1285 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1286 
1287 	status = nfsd4_decode_opaque(argp, &exid->clname);
1288 	if (status)
1289 		return nfserr_bad_xdr;
1290 
1291 	READ_BUF(4);
1292 	exid->flags = be32_to_cpup(p++);
1293 
1294 	/* Ignore state_protect4_a */
1295 	READ_BUF(4);
1296 	exid->spa_how = be32_to_cpup(p++);
1297 	switch (exid->spa_how) {
1298 	case SP4_NONE:
1299 		break;
1300 	case SP4_MACH_CRED:
1301 		/* spo_must_enforce */
1302 		status = nfsd4_decode_bitmap(argp,
1303 					exid->spo_must_enforce);
1304 		if (status)
1305 			goto out;
1306 		/* spo_must_allow */
1307 		status = nfsd4_decode_bitmap(argp, exid->spo_must_allow);
1308 		if (status)
1309 			goto out;
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);
1839 	SAVEMEM(argp->tag, argp->taglen);
1840 	READ_BUF(8);
1841 	argp->minorversion = be32_to_cpup(p++);
1842 	argp->opcnt = be32_to_cpup(p++);
1843 	max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
1844 
1845 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1846 		goto xdr_error;
1847 	if (argp->opcnt > 100)
1848 		goto xdr_error;
1849 
1850 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1851 		argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1852 		if (!argp->ops) {
1853 			argp->ops = argp->iops;
1854 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1855 			goto xdr_error;
1856 		}
1857 	}
1858 
1859 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
1860 		argp->opcnt = 0;
1861 
1862 	for (i = 0; i < argp->opcnt; i++) {
1863 		op = &argp->ops[i];
1864 		op->replay = NULL;
1865 
1866 		READ_BUF(4);
1867 		op->opnum = be32_to_cpup(p++);
1868 
1869 		if (nfsd4_opnum_in_range(argp, op))
1870 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
1871 		else {
1872 			op->opnum = OP_ILLEGAL;
1873 			op->status = nfserr_op_illegal;
1874 		}
1875 		/*
1876 		 * We'll try to cache the result in the DRC if any one
1877 		 * op in the compound wants to be cached:
1878 		 */
1879 		cachethis |= nfsd4_cache_this_op(op);
1880 
1881 		if (op->opnum == OP_READ) {
1882 			readcount++;
1883 			readbytes += nfsd4_max_reply(argp->rqstp, op);
1884 		} else
1885 			max_reply += nfsd4_max_reply(argp->rqstp, op);
1886 		/*
1887 		 * OP_LOCK may return a conflicting lock.  (Special case
1888 		 * because it will just skip encoding this if it runs
1889 		 * out of xdr buffer space, and it is the only operation
1890 		 * that behaves this way.)
1891 		 */
1892 		if (op->opnum == OP_LOCK)
1893 			max_reply += NFS4_OPAQUE_LIMIT;
1894 
1895 		if (op->status) {
1896 			argp->opcnt = i+1;
1897 			break;
1898 		}
1899 	}
1900 	/* Sessions make the DRC unnecessary: */
1901 	if (argp->minorversion)
1902 		cachethis = false;
1903 	svc_reserve(argp->rqstp, max_reply + readbytes);
1904 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1905 
1906 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
1907 		clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
1908 
1909 	DECODE_TAIL;
1910 }
1911 
1912 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode)
1913 {
1914 	if (IS_I_VERSION(inode)) {
1915 		p = xdr_encode_hyper(p, inode->i_version);
1916 	} else {
1917 		*p++ = cpu_to_be32(stat->ctime.tv_sec);
1918 		*p++ = cpu_to_be32(stat->ctime.tv_nsec);
1919 	}
1920 	return p;
1921 }
1922 
1923 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
1924 {
1925 	*p++ = cpu_to_be32(c->atomic);
1926 	if (c->change_supported) {
1927 		p = xdr_encode_hyper(p, c->before_change);
1928 		p = xdr_encode_hyper(p, c->after_change);
1929 	} else {
1930 		*p++ = cpu_to_be32(c->before_ctime_sec);
1931 		*p++ = cpu_to_be32(c->before_ctime_nsec);
1932 		*p++ = cpu_to_be32(c->after_ctime_sec);
1933 		*p++ = cpu_to_be32(c->after_ctime_nsec);
1934 	}
1935 	return p;
1936 }
1937 
1938 /* Encode as an array of strings the string given with components
1939  * separated @sep, escaped with esc_enter and esc_exit.
1940  */
1941 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
1942 					  char *components, char esc_enter,
1943 					  char esc_exit)
1944 {
1945 	__be32 *p;
1946 	__be32 pathlen;
1947 	int pathlen_offset;
1948 	int strlen, count=0;
1949 	char *str, *end, *next;
1950 
1951 	dprintk("nfsd4_encode_components(%s)\n", components);
1952 
1953 	pathlen_offset = xdr->buf->len;
1954 	p = xdr_reserve_space(xdr, 4);
1955 	if (!p)
1956 		return nfserr_resource;
1957 	p++; /* We will fill this in with @count later */
1958 
1959 	end = str = components;
1960 	while (*end) {
1961 		bool found_esc = false;
1962 
1963 		/* try to parse as esc_start, ..., esc_end, sep */
1964 		if (*str == esc_enter) {
1965 			for (; *end && (*end != esc_exit); end++)
1966 				/* find esc_exit or end of string */;
1967 			next = end + 1;
1968 			if (*end && (!*next || *next == sep)) {
1969 				str++;
1970 				found_esc = true;
1971 			}
1972 		}
1973 
1974 		if (!found_esc)
1975 			for (; *end && (*end != sep); end++)
1976 				/* find sep or end of string */;
1977 
1978 		strlen = end - str;
1979 		if (strlen) {
1980 			p = xdr_reserve_space(xdr, strlen + 4);
1981 			if (!p)
1982 				return nfserr_resource;
1983 			p = xdr_encode_opaque(p, str, strlen);
1984 			count++;
1985 		}
1986 		else
1987 			end++;
1988 		if (found_esc)
1989 			end = next;
1990 
1991 		str = end;
1992 	}
1993 	pathlen = htonl(count);
1994 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
1995 	return 0;
1996 }
1997 
1998 /* Encode as an array of strings the string given with components
1999  * separated @sep.
2000  */
2001 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
2002 				      char *components)
2003 {
2004 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
2005 }
2006 
2007 /*
2008  * encode a location element of a fs_locations structure
2009  */
2010 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
2011 					struct nfsd4_fs_location *location)
2012 {
2013 	__be32 status;
2014 
2015 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
2016 						'[', ']');
2017 	if (status)
2018 		return status;
2019 	status = nfsd4_encode_components(xdr, '/', location->path);
2020 	if (status)
2021 		return status;
2022 	return 0;
2023 }
2024 
2025 /*
2026  * Encode a path in RFC3530 'pathname4' format
2027  */
2028 static __be32 nfsd4_encode_path(struct xdr_stream *xdr,
2029 				const struct path *root,
2030 				const struct path *path)
2031 {
2032 	struct path cur = *path;
2033 	__be32 *p;
2034 	struct dentry **components = NULL;
2035 	unsigned int ncomponents = 0;
2036 	__be32 err = nfserr_jukebox;
2037 
2038 	dprintk("nfsd4_encode_components(");
2039 
2040 	path_get(&cur);
2041 	/* First walk the path up to the nfsd root, and store the
2042 	 * dentries/path components in an array.
2043 	 */
2044 	for (;;) {
2045 		if (path_equal(&cur, root))
2046 			break;
2047 		if (cur.dentry == cur.mnt->mnt_root) {
2048 			if (follow_up(&cur))
2049 				continue;
2050 			goto out_free;
2051 		}
2052 		if ((ncomponents & 15) == 0) {
2053 			struct dentry **new;
2054 			new = krealloc(components,
2055 					sizeof(*new) * (ncomponents + 16),
2056 					GFP_KERNEL);
2057 			if (!new)
2058 				goto out_free;
2059 			components = new;
2060 		}
2061 		components[ncomponents++] = cur.dentry;
2062 		cur.dentry = dget_parent(cur.dentry);
2063 	}
2064 	err = nfserr_resource;
2065 	p = xdr_reserve_space(xdr, 4);
2066 	if (!p)
2067 		goto out_free;
2068 	*p++ = cpu_to_be32(ncomponents);
2069 
2070 	while (ncomponents) {
2071 		struct dentry *dentry = components[ncomponents - 1];
2072 		unsigned int len;
2073 
2074 		spin_lock(&dentry->d_lock);
2075 		len = dentry->d_name.len;
2076 		p = xdr_reserve_space(xdr, len + 4);
2077 		if (!p) {
2078 			spin_unlock(&dentry->d_lock);
2079 			goto out_free;
2080 		}
2081 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
2082 		dprintk("/%pd", dentry);
2083 		spin_unlock(&dentry->d_lock);
2084 		dput(dentry);
2085 		ncomponents--;
2086 	}
2087 
2088 	err = 0;
2089 out_free:
2090 	dprintk(")\n");
2091 	while (ncomponents)
2092 		dput(components[--ncomponents]);
2093 	kfree(components);
2094 	path_put(&cur);
2095 	return err;
2096 }
2097 
2098 static __be32 nfsd4_encode_fsloc_fsroot(struct xdr_stream *xdr,
2099 			struct svc_rqst *rqstp, const struct path *path)
2100 {
2101 	struct svc_export *exp_ps;
2102 	__be32 res;
2103 
2104 	exp_ps = rqst_find_fsidzero_export(rqstp);
2105 	if (IS_ERR(exp_ps))
2106 		return nfserrno(PTR_ERR(exp_ps));
2107 	res = nfsd4_encode_path(xdr, &exp_ps->ex_path, path);
2108 	exp_put(exp_ps);
2109 	return res;
2110 }
2111 
2112 /*
2113  *  encode a fs_locations structure
2114  */
2115 static __be32 nfsd4_encode_fs_locations(struct xdr_stream *xdr,
2116 			struct svc_rqst *rqstp, struct svc_export *exp)
2117 {
2118 	__be32 status;
2119 	int i;
2120 	__be32 *p;
2121 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
2122 
2123 	status = nfsd4_encode_fsloc_fsroot(xdr, rqstp, &exp->ex_path);
2124 	if (status)
2125 		return status;
2126 	p = xdr_reserve_space(xdr, 4);
2127 	if (!p)
2128 		return nfserr_resource;
2129 	*p++ = cpu_to_be32(fslocs->locations_count);
2130 	for (i=0; i<fslocs->locations_count; i++) {
2131 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
2132 		if (status)
2133 			return status;
2134 	}
2135 	return 0;
2136 }
2137 
2138 static u32 nfs4_file_type(umode_t mode)
2139 {
2140 	switch (mode & S_IFMT) {
2141 	case S_IFIFO:	return NF4FIFO;
2142 	case S_IFCHR:	return NF4CHR;
2143 	case S_IFDIR:	return NF4DIR;
2144 	case S_IFBLK:	return NF4BLK;
2145 	case S_IFLNK:	return NF4LNK;
2146 	case S_IFREG:	return NF4REG;
2147 	case S_IFSOCK:	return NF4SOCK;
2148 	default:	return NF4BAD;
2149 	};
2150 }
2151 
2152 static inline __be32
2153 nfsd4_encode_aclname(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2154 		     struct nfs4_ace *ace)
2155 {
2156 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
2157 		return nfs4_acl_write_who(xdr, ace->whotype);
2158 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
2159 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
2160 	else
2161 		return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
2162 }
2163 
2164 static inline __be32
2165 nfsd4_encode_layout_types(struct xdr_stream *xdr, u32 layout_types)
2166 {
2167 	__be32		*p;
2168 	unsigned long	i = hweight_long(layout_types);
2169 
2170 	p = xdr_reserve_space(xdr, 4 + 4 * i);
2171 	if (!p)
2172 		return nfserr_resource;
2173 
2174 	*p++ = cpu_to_be32(i);
2175 
2176 	for (i = LAYOUT_NFSV4_1_FILES; i < LAYOUT_TYPE_MAX; ++i)
2177 		if (layout_types & (1 << i))
2178 			*p++ = cpu_to_be32(i);
2179 
2180 	return 0;
2181 }
2182 
2183 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
2184 			      FATTR4_WORD0_RDATTR_ERROR)
2185 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2186 #define WORD2_ABSENT_FS_ATTRS 0
2187 
2188 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2189 static inline __be32
2190 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2191 			    void *context, int len)
2192 {
2193 	__be32 *p;
2194 
2195 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2196 	if (!p)
2197 		return nfserr_resource;
2198 
2199 	/*
2200 	 * For now we use a 0 here to indicate the null translation; in
2201 	 * the future we may place a call to translation code here.
2202 	 */
2203 	*p++ = cpu_to_be32(0); /* lfs */
2204 	*p++ = cpu_to_be32(0); /* pi */
2205 	p = xdr_encode_opaque(p, context, len);
2206 	return 0;
2207 }
2208 #else
2209 static inline __be32
2210 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2211 			    void *context, int len)
2212 { return 0; }
2213 #endif
2214 
2215 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *bmval2, u32 *rdattr_err)
2216 {
2217 	/* As per referral draft:  */
2218 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2219 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2220 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2221 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2222 			*rdattr_err = NFSERR_MOVED;
2223 		else
2224 			return nfserr_moved;
2225 	}
2226 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2227 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2228 	*bmval2 &= WORD2_ABSENT_FS_ATTRS;
2229 	return 0;
2230 }
2231 
2232 
2233 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2234 {
2235 	struct path path = exp->ex_path;
2236 	int err;
2237 
2238 	path_get(&path);
2239 	while (follow_up(&path)) {
2240 		if (path.dentry != path.mnt->mnt_root)
2241 			break;
2242 	}
2243 	err = vfs_getattr(&path, stat);
2244 	path_put(&path);
2245 	return err;
2246 }
2247 
2248 static __be32
2249 nfsd4_encode_bitmap(struct xdr_stream *xdr, u32 bmval0, u32 bmval1, u32 bmval2)
2250 {
2251 	__be32 *p;
2252 
2253 	if (bmval2) {
2254 		p = xdr_reserve_space(xdr, 16);
2255 		if (!p)
2256 			goto out_resource;
2257 		*p++ = cpu_to_be32(3);
2258 		*p++ = cpu_to_be32(bmval0);
2259 		*p++ = cpu_to_be32(bmval1);
2260 		*p++ = cpu_to_be32(bmval2);
2261 	} else if (bmval1) {
2262 		p = xdr_reserve_space(xdr, 12);
2263 		if (!p)
2264 			goto out_resource;
2265 		*p++ = cpu_to_be32(2);
2266 		*p++ = cpu_to_be32(bmval0);
2267 		*p++ = cpu_to_be32(bmval1);
2268 	} else {
2269 		p = xdr_reserve_space(xdr, 8);
2270 		if (!p)
2271 			goto out_resource;
2272 		*p++ = cpu_to_be32(1);
2273 		*p++ = cpu_to_be32(bmval0);
2274 	}
2275 
2276 	return 0;
2277 out_resource:
2278 	return nfserr_resource;
2279 }
2280 
2281 /*
2282  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2283  * ourselves.
2284  */
2285 static __be32
2286 nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
2287 		struct svc_export *exp,
2288 		struct dentry *dentry, u32 *bmval,
2289 		struct svc_rqst *rqstp, int ignore_crossmnt)
2290 {
2291 	u32 bmval0 = bmval[0];
2292 	u32 bmval1 = bmval[1];
2293 	u32 bmval2 = bmval[2];
2294 	struct kstat stat;
2295 	struct svc_fh *tempfh = NULL;
2296 	struct kstatfs statfs;
2297 	__be32 *p;
2298 	int starting_len = xdr->buf->len;
2299 	int attrlen_offset;
2300 	__be32 attrlen;
2301 	u32 dummy;
2302 	u64 dummy64;
2303 	u32 rdattr_err = 0;
2304 	__be32 status;
2305 	int err;
2306 	struct nfs4_acl *acl = NULL;
2307 	void *context = NULL;
2308 	int contextlen;
2309 	bool contextsupport = false;
2310 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2311 	u32 minorversion = resp->cstate.minorversion;
2312 	struct path path = {
2313 		.mnt	= exp->ex_path.mnt,
2314 		.dentry	= dentry,
2315 	};
2316 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2317 
2318 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2319 	BUG_ON(bmval0 & ~nfsd_suppattrs0(minorversion));
2320 	BUG_ON(bmval1 & ~nfsd_suppattrs1(minorversion));
2321 	BUG_ON(bmval2 & ~nfsd_suppattrs2(minorversion));
2322 
2323 	if (exp->ex_fslocs.migrated) {
2324 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &bmval2, &rdattr_err);
2325 		if (status)
2326 			goto out;
2327 	}
2328 
2329 	err = vfs_getattr(&path, &stat);
2330 	if (err)
2331 		goto out_nfserr;
2332 	if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
2333 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
2334 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2335 		       FATTR4_WORD1_SPACE_TOTAL))) {
2336 		err = vfs_statfs(&path, &statfs);
2337 		if (err)
2338 			goto out_nfserr;
2339 	}
2340 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2341 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2342 		status = nfserr_jukebox;
2343 		if (!tempfh)
2344 			goto out;
2345 		fh_init(tempfh, NFS4_FHSIZE);
2346 		status = fh_compose(tempfh, exp, dentry, NULL);
2347 		if (status)
2348 			goto out;
2349 		fhp = tempfh;
2350 	}
2351 	if (bmval0 & FATTR4_WORD0_ACL) {
2352 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2353 		if (err == -EOPNOTSUPP)
2354 			bmval0 &= ~FATTR4_WORD0_ACL;
2355 		else if (err == -EINVAL) {
2356 			status = nfserr_attrnotsupp;
2357 			goto out;
2358 		} else if (err != 0)
2359 			goto out_nfserr;
2360 	}
2361 
2362 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2363 	if ((bmval2 & FATTR4_WORD2_SECURITY_LABEL) ||
2364 	     bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2365 		err = security_inode_getsecctx(d_inode(dentry),
2366 						&context, &contextlen);
2367 		contextsupport = (err == 0);
2368 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2369 			if (err == -EOPNOTSUPP)
2370 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2371 			else if (err)
2372 				goto out_nfserr;
2373 		}
2374 	}
2375 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2376 
2377 	status = nfsd4_encode_bitmap(xdr, bmval0, bmval1, bmval2);
2378 	if (status)
2379 		goto out;
2380 
2381 	attrlen_offset = xdr->buf->len;
2382 	p = xdr_reserve_space(xdr, 4);
2383 	if (!p)
2384 		goto out_resource;
2385 	p++;                /* to be backfilled later */
2386 
2387 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2388 		u32 word0 = nfsd_suppattrs0(minorversion);
2389 		u32 word1 = nfsd_suppattrs1(minorversion);
2390 		u32 word2 = nfsd_suppattrs2(minorversion);
2391 
2392 		if (!IS_POSIXACL(dentry->d_inode))
2393 			word0 &= ~FATTR4_WORD0_ACL;
2394 		if (!contextsupport)
2395 			word2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2396 		if (!word2) {
2397 			p = xdr_reserve_space(xdr, 12);
2398 			if (!p)
2399 				goto out_resource;
2400 			*p++ = cpu_to_be32(2);
2401 			*p++ = cpu_to_be32(word0);
2402 			*p++ = cpu_to_be32(word1);
2403 		} else {
2404 			p = xdr_reserve_space(xdr, 16);
2405 			if (!p)
2406 				goto out_resource;
2407 			*p++ = cpu_to_be32(3);
2408 			*p++ = cpu_to_be32(word0);
2409 			*p++ = cpu_to_be32(word1);
2410 			*p++ = cpu_to_be32(word2);
2411 		}
2412 	}
2413 	if (bmval0 & FATTR4_WORD0_TYPE) {
2414 		p = xdr_reserve_space(xdr, 4);
2415 		if (!p)
2416 			goto out_resource;
2417 		dummy = nfs4_file_type(stat.mode);
2418 		if (dummy == NF4BAD) {
2419 			status = nfserr_serverfault;
2420 			goto out;
2421 		}
2422 		*p++ = cpu_to_be32(dummy);
2423 	}
2424 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2425 		p = xdr_reserve_space(xdr, 4);
2426 		if (!p)
2427 			goto out_resource;
2428 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2429 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT);
2430 		else
2431 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT|
2432 						NFS4_FH_VOL_RENAME);
2433 	}
2434 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2435 		p = xdr_reserve_space(xdr, 8);
2436 		if (!p)
2437 			goto out_resource;
2438 		p = encode_change(p, &stat, d_inode(dentry));
2439 	}
2440 	if (bmval0 & FATTR4_WORD0_SIZE) {
2441 		p = xdr_reserve_space(xdr, 8);
2442 		if (!p)
2443 			goto out_resource;
2444 		p = xdr_encode_hyper(p, stat.size);
2445 	}
2446 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2447 		p = xdr_reserve_space(xdr, 4);
2448 		if (!p)
2449 			goto out_resource;
2450 		*p++ = cpu_to_be32(1);
2451 	}
2452 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2453 		p = xdr_reserve_space(xdr, 4);
2454 		if (!p)
2455 			goto out_resource;
2456 		*p++ = cpu_to_be32(1);
2457 	}
2458 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2459 		p = xdr_reserve_space(xdr, 4);
2460 		if (!p)
2461 			goto out_resource;
2462 		*p++ = cpu_to_be32(0);
2463 	}
2464 	if (bmval0 & FATTR4_WORD0_FSID) {
2465 		p = xdr_reserve_space(xdr, 16);
2466 		if (!p)
2467 			goto out_resource;
2468 		if (exp->ex_fslocs.migrated) {
2469 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
2470 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
2471 		} else switch(fsid_source(fhp)) {
2472 		case FSIDSOURCE_FSID:
2473 			p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
2474 			p = xdr_encode_hyper(p, (u64)0);
2475 			break;
2476 		case FSIDSOURCE_DEV:
2477 			*p++ = cpu_to_be32(0);
2478 			*p++ = cpu_to_be32(MAJOR(stat.dev));
2479 			*p++ = cpu_to_be32(0);
2480 			*p++ = cpu_to_be32(MINOR(stat.dev));
2481 			break;
2482 		case FSIDSOURCE_UUID:
2483 			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
2484 								EX_UUID_LEN);
2485 			break;
2486 		}
2487 	}
2488 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2489 		p = xdr_reserve_space(xdr, 4);
2490 		if (!p)
2491 			goto out_resource;
2492 		*p++ = cpu_to_be32(0);
2493 	}
2494 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2495 		p = xdr_reserve_space(xdr, 4);
2496 		if (!p)
2497 			goto out_resource;
2498 		*p++ = cpu_to_be32(nn->nfsd4_lease);
2499 	}
2500 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2501 		p = xdr_reserve_space(xdr, 4);
2502 		if (!p)
2503 			goto out_resource;
2504 		*p++ = cpu_to_be32(rdattr_err);
2505 	}
2506 	if (bmval0 & FATTR4_WORD0_ACL) {
2507 		struct nfs4_ace *ace;
2508 
2509 		if (acl == NULL) {
2510 			p = xdr_reserve_space(xdr, 4);
2511 			if (!p)
2512 				goto out_resource;
2513 
2514 			*p++ = cpu_to_be32(0);
2515 			goto out_acl;
2516 		}
2517 		p = xdr_reserve_space(xdr, 4);
2518 		if (!p)
2519 			goto out_resource;
2520 		*p++ = cpu_to_be32(acl->naces);
2521 
2522 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2523 			p = xdr_reserve_space(xdr, 4*3);
2524 			if (!p)
2525 				goto out_resource;
2526 			*p++ = cpu_to_be32(ace->type);
2527 			*p++ = cpu_to_be32(ace->flag);
2528 			*p++ = cpu_to_be32(ace->access_mask &
2529 							NFS4_ACE_MASK_ALL);
2530 			status = nfsd4_encode_aclname(xdr, rqstp, ace);
2531 			if (status)
2532 				goto out;
2533 		}
2534 	}
2535 out_acl:
2536 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2537 		p = xdr_reserve_space(xdr, 4);
2538 		if (!p)
2539 			goto out_resource;
2540 		*p++ = cpu_to_be32(IS_POSIXACL(dentry->d_inode) ?
2541 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2542 	}
2543 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2544 		p = xdr_reserve_space(xdr, 4);
2545 		if (!p)
2546 			goto out_resource;
2547 		*p++ = cpu_to_be32(1);
2548 	}
2549 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2550 		p = xdr_reserve_space(xdr, 4);
2551 		if (!p)
2552 			goto out_resource;
2553 		*p++ = cpu_to_be32(0);
2554 	}
2555 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2556 		p = xdr_reserve_space(xdr, 4);
2557 		if (!p)
2558 			goto out_resource;
2559 		*p++ = cpu_to_be32(1);
2560 	}
2561 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2562 		p = xdr_reserve_space(xdr, 4);
2563 		if (!p)
2564 			goto out_resource;
2565 		*p++ = cpu_to_be32(1);
2566 	}
2567 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2568 		p = xdr_reserve_space(xdr, fhp->fh_handle.fh_size + 4);
2569 		if (!p)
2570 			goto out_resource;
2571 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base,
2572 					fhp->fh_handle.fh_size);
2573 	}
2574 	if (bmval0 & FATTR4_WORD0_FILEID) {
2575 		p = xdr_reserve_space(xdr, 8);
2576 		if (!p)
2577 			goto out_resource;
2578 		p = xdr_encode_hyper(p, stat.ino);
2579 	}
2580 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2581 		p = xdr_reserve_space(xdr, 8);
2582 		if (!p)
2583 			goto out_resource;
2584 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2585 	}
2586 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2587 		p = xdr_reserve_space(xdr, 8);
2588 		if (!p)
2589 			goto out_resource;
2590 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2591 	}
2592 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2593 		p = xdr_reserve_space(xdr, 8);
2594 		if (!p)
2595 			goto out_resource;
2596 		p = xdr_encode_hyper(p, (u64) statfs.f_files);
2597 	}
2598 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2599 		status = nfsd4_encode_fs_locations(xdr, rqstp, exp);
2600 		if (status)
2601 			goto out;
2602 	}
2603 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2604 		p = xdr_reserve_space(xdr, 4);
2605 		if (!p)
2606 			goto out_resource;
2607 		*p++ = cpu_to_be32(1);
2608 	}
2609 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2610 		p = xdr_reserve_space(xdr, 8);
2611 		if (!p)
2612 			goto out_resource;
2613 		p = xdr_encode_hyper(p, exp->ex_path.mnt->mnt_sb->s_maxbytes);
2614 	}
2615 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2616 		p = xdr_reserve_space(xdr, 4);
2617 		if (!p)
2618 			goto out_resource;
2619 		*p++ = cpu_to_be32(255);
2620 	}
2621 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2622 		p = xdr_reserve_space(xdr, 4);
2623 		if (!p)
2624 			goto out_resource;
2625 		*p++ = cpu_to_be32(statfs.f_namelen);
2626 	}
2627 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2628 		p = xdr_reserve_space(xdr, 8);
2629 		if (!p)
2630 			goto out_resource;
2631 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2632 	}
2633 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2634 		p = xdr_reserve_space(xdr, 8);
2635 		if (!p)
2636 			goto out_resource;
2637 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2638 	}
2639 	if (bmval1 & FATTR4_WORD1_MODE) {
2640 		p = xdr_reserve_space(xdr, 4);
2641 		if (!p)
2642 			goto out_resource;
2643 		*p++ = cpu_to_be32(stat.mode & S_IALLUGO);
2644 	}
2645 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2646 		p = xdr_reserve_space(xdr, 4);
2647 		if (!p)
2648 			goto out_resource;
2649 		*p++ = cpu_to_be32(1);
2650 	}
2651 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2652 		p = xdr_reserve_space(xdr, 4);
2653 		if (!p)
2654 			goto out_resource;
2655 		*p++ = cpu_to_be32(stat.nlink);
2656 	}
2657 	if (bmval1 & FATTR4_WORD1_OWNER) {
2658 		status = nfsd4_encode_user(xdr, rqstp, stat.uid);
2659 		if (status)
2660 			goto out;
2661 	}
2662 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2663 		status = nfsd4_encode_group(xdr, rqstp, stat.gid);
2664 		if (status)
2665 			goto out;
2666 	}
2667 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2668 		p = xdr_reserve_space(xdr, 8);
2669 		if (!p)
2670 			goto out_resource;
2671 		*p++ = cpu_to_be32((u32) MAJOR(stat.rdev));
2672 		*p++ = cpu_to_be32((u32) MINOR(stat.rdev));
2673 	}
2674 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2675 		p = xdr_reserve_space(xdr, 8);
2676 		if (!p)
2677 			goto out_resource;
2678 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2679 		p = xdr_encode_hyper(p, dummy64);
2680 	}
2681 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2682 		p = xdr_reserve_space(xdr, 8);
2683 		if (!p)
2684 			goto out_resource;
2685 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2686 		p = xdr_encode_hyper(p, dummy64);
2687 	}
2688 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2689 		p = xdr_reserve_space(xdr, 8);
2690 		if (!p)
2691 			goto out_resource;
2692 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2693 		p = xdr_encode_hyper(p, dummy64);
2694 	}
2695 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2696 		p = xdr_reserve_space(xdr, 8);
2697 		if (!p)
2698 			goto out_resource;
2699 		dummy64 = (u64)stat.blocks << 9;
2700 		p = xdr_encode_hyper(p, dummy64);
2701 	}
2702 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2703 		p = xdr_reserve_space(xdr, 12);
2704 		if (!p)
2705 			goto out_resource;
2706 		p = xdr_encode_hyper(p, (s64)stat.atime.tv_sec);
2707 		*p++ = cpu_to_be32(stat.atime.tv_nsec);
2708 	}
2709 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2710 		p = xdr_reserve_space(xdr, 12);
2711 		if (!p)
2712 			goto out_resource;
2713 		*p++ = cpu_to_be32(0);
2714 		*p++ = cpu_to_be32(1);
2715 		*p++ = cpu_to_be32(0);
2716 	}
2717 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2718 		p = xdr_reserve_space(xdr, 12);
2719 		if (!p)
2720 			goto out_resource;
2721 		p = xdr_encode_hyper(p, (s64)stat.ctime.tv_sec);
2722 		*p++ = cpu_to_be32(stat.ctime.tv_nsec);
2723 	}
2724 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2725 		p = xdr_reserve_space(xdr, 12);
2726 		if (!p)
2727 			goto out_resource;
2728 		p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
2729 		*p++ = cpu_to_be32(stat.mtime.tv_nsec);
2730 	}
2731 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2732 		struct kstat parent_stat;
2733 		u64 ino = stat.ino;
2734 
2735 		p = xdr_reserve_space(xdr, 8);
2736 		if (!p)
2737                 	goto out_resource;
2738 		/*
2739 		 * Get parent's attributes if not ignoring crossmount
2740 		 * and this is the root of a cross-mounted filesystem.
2741 		 */
2742 		if (ignore_crossmnt == 0 &&
2743 		    dentry == exp->ex_path.mnt->mnt_root) {
2744 			err = get_parent_attributes(exp, &parent_stat);
2745 			if (err)
2746 				goto out_nfserr;
2747 			ino = parent_stat.ino;
2748 		}
2749 		p = xdr_encode_hyper(p, ino);
2750 	}
2751 #ifdef CONFIG_NFSD_PNFS
2752 	if (bmval1 & FATTR4_WORD1_FS_LAYOUT_TYPES) {
2753 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
2754 		if (status)
2755 			goto out;
2756 	}
2757 
2758 	if (bmval2 & FATTR4_WORD2_LAYOUT_TYPES) {
2759 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
2760 		if (status)
2761 			goto out;
2762 	}
2763 
2764 	if (bmval2 & FATTR4_WORD2_LAYOUT_BLKSIZE) {
2765 		p = xdr_reserve_space(xdr, 4);
2766 		if (!p)
2767 			goto out_resource;
2768 		*p++ = cpu_to_be32(stat.blksize);
2769 	}
2770 #endif /* CONFIG_NFSD_PNFS */
2771 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2772 		status = nfsd4_encode_bitmap(xdr, NFSD_SUPPATTR_EXCLCREAT_WORD0,
2773 						  NFSD_SUPPATTR_EXCLCREAT_WORD1,
2774 						  NFSD_SUPPATTR_EXCLCREAT_WORD2);
2775 		if (status)
2776 			goto out;
2777 	}
2778 
2779 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2780 		status = nfsd4_encode_security_label(xdr, rqstp, context,
2781 								contextlen);
2782 		if (status)
2783 			goto out;
2784 	}
2785 
2786 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
2787 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
2788 	status = nfs_ok;
2789 
2790 out:
2791 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2792 	if (context)
2793 		security_release_secctx(context, contextlen);
2794 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2795 	kfree(acl);
2796 	if (tempfh) {
2797 		fh_put(tempfh);
2798 		kfree(tempfh);
2799 	}
2800 	if (status)
2801 		xdr_truncate_encode(xdr, starting_len);
2802 	return status;
2803 out_nfserr:
2804 	status = nfserrno(err);
2805 	goto out;
2806 out_resource:
2807 	status = nfserr_resource;
2808 	goto out;
2809 }
2810 
2811 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
2812 				struct xdr_buf *buf, __be32 *p, int bytes)
2813 {
2814 	xdr->scratch.iov_len = 0;
2815 	memset(buf, 0, sizeof(struct xdr_buf));
2816 	buf->head[0].iov_base = p;
2817 	buf->head[0].iov_len = 0;
2818 	buf->len = 0;
2819 	xdr->buf = buf;
2820 	xdr->iov = buf->head;
2821 	xdr->p = p;
2822 	xdr->end = (void *)p + bytes;
2823 	buf->buflen = bytes;
2824 }
2825 
2826 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
2827 			struct svc_fh *fhp, struct svc_export *exp,
2828 			struct dentry *dentry, u32 *bmval,
2829 			struct svc_rqst *rqstp, int ignore_crossmnt)
2830 {
2831 	struct xdr_buf dummy;
2832 	struct xdr_stream xdr;
2833 	__be32 ret;
2834 
2835 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
2836 	ret = nfsd4_encode_fattr(&xdr, fhp, exp, dentry, bmval, rqstp,
2837 							ignore_crossmnt);
2838 	*p = xdr.p;
2839 	return ret;
2840 }
2841 
2842 static inline int attributes_need_mount(u32 *bmval)
2843 {
2844 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2845 		return 1;
2846 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2847 		return 1;
2848 	return 0;
2849 }
2850 
2851 static __be32
2852 nfsd4_encode_dirent_fattr(struct xdr_stream *xdr, struct nfsd4_readdir *cd,
2853 			const char *name, int namlen)
2854 {
2855 	struct svc_export *exp = cd->rd_fhp->fh_export;
2856 	struct dentry *dentry;
2857 	__be32 nfserr;
2858 	int ignore_crossmnt = 0;
2859 
2860 	dentry = lookup_one_len_unlocked(name, cd->rd_fhp->fh_dentry, namlen);
2861 	if (IS_ERR(dentry))
2862 		return nfserrno(PTR_ERR(dentry));
2863 	if (d_really_is_negative(dentry)) {
2864 		/*
2865 		 * we're not holding the i_mutex here, so there's
2866 		 * a window where this directory entry could have gone
2867 		 * away.
2868 		 */
2869 		dput(dentry);
2870 		return nfserr_noent;
2871 	}
2872 
2873 	exp_get(exp);
2874 	/*
2875 	 * In the case of a mountpoint, the client may be asking for
2876 	 * attributes that are only properties of the underlying filesystem
2877 	 * as opposed to the cross-mounted file system. In such a case,
2878 	 * we will not follow the cross mount and will fill the attribtutes
2879 	 * directly from the mountpoint dentry.
2880 	 */
2881 	if (nfsd_mountpoint(dentry, exp)) {
2882 		int err;
2883 
2884 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
2885 				&& !attributes_need_mount(cd->rd_bmval)) {
2886 			ignore_crossmnt = 1;
2887 			goto out_encode;
2888 		}
2889 		/*
2890 		 * Why the heck aren't we just using nfsd_lookup??
2891 		 * Different "."/".." handling?  Something else?
2892 		 * At least, add a comment here to explain....
2893 		 */
2894 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
2895 		if (err) {
2896 			nfserr = nfserrno(err);
2897 			goto out_put;
2898 		}
2899 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
2900 		if (nfserr)
2901 			goto out_put;
2902 
2903 	}
2904 out_encode:
2905 	nfserr = nfsd4_encode_fattr(xdr, NULL, exp, dentry, cd->rd_bmval,
2906 					cd->rd_rqstp, ignore_crossmnt);
2907 out_put:
2908 	dput(dentry);
2909 	exp_put(exp);
2910 	return nfserr;
2911 }
2912 
2913 static __be32 *
2914 nfsd4_encode_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
2915 {
2916 	__be32 *p;
2917 
2918 	p = xdr_reserve_space(xdr, 20);
2919 	if (!p)
2920 		return NULL;
2921 	*p++ = htonl(2);
2922 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
2923 	*p++ = htonl(0);			 /* bmval1 */
2924 
2925 	*p++ = htonl(4);     /* attribute length */
2926 	*p++ = nfserr;       /* no htonl */
2927 	return p;
2928 }
2929 
2930 static int
2931 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
2932 		    loff_t offset, u64 ino, unsigned int d_type)
2933 {
2934 	struct readdir_cd *ccd = ccdv;
2935 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
2936 	struct xdr_stream *xdr = cd->xdr;
2937 	int start_offset = xdr->buf->len;
2938 	int cookie_offset;
2939 	u32 name_and_cookie;
2940 	int entry_bytes;
2941 	__be32 nfserr = nfserr_toosmall;
2942 	__be64 wire_offset;
2943 	__be32 *p;
2944 
2945 	/* In nfsv4, "." and ".." never make it onto the wire.. */
2946 	if (name && isdotent(name, namlen)) {
2947 		cd->common.err = nfs_ok;
2948 		return 0;
2949 	}
2950 
2951 	if (cd->cookie_offset) {
2952 		wire_offset = cpu_to_be64(offset);
2953 		write_bytes_to_xdr_buf(xdr->buf, cd->cookie_offset,
2954 							&wire_offset, 8);
2955 	}
2956 
2957 	p = xdr_reserve_space(xdr, 4);
2958 	if (!p)
2959 		goto fail;
2960 	*p++ = xdr_one;                             /* mark entry present */
2961 	cookie_offset = xdr->buf->len;
2962 	p = xdr_reserve_space(xdr, 3*4 + namlen);
2963 	if (!p)
2964 		goto fail;
2965 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
2966 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
2967 
2968 	nfserr = nfsd4_encode_dirent_fattr(xdr, cd, name, namlen);
2969 	switch (nfserr) {
2970 	case nfs_ok:
2971 		break;
2972 	case nfserr_resource:
2973 		nfserr = nfserr_toosmall;
2974 		goto fail;
2975 	case nfserr_noent:
2976 		xdr_truncate_encode(xdr, start_offset);
2977 		goto skip_entry;
2978 	default:
2979 		/*
2980 		 * If the client requested the RDATTR_ERROR attribute,
2981 		 * we stuff the error code into this attribute
2982 		 * and continue.  If this attribute was not requested,
2983 		 * then in accordance with the spec, we fail the
2984 		 * entire READDIR operation(!)
2985 		 */
2986 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
2987 			goto fail;
2988 		p = nfsd4_encode_rdattr_error(xdr, nfserr);
2989 		if (p == NULL) {
2990 			nfserr = nfserr_toosmall;
2991 			goto fail;
2992 		}
2993 	}
2994 	nfserr = nfserr_toosmall;
2995 	entry_bytes = xdr->buf->len - start_offset;
2996 	if (entry_bytes > cd->rd_maxcount)
2997 		goto fail;
2998 	cd->rd_maxcount -= entry_bytes;
2999 	/*
3000 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so
3001 	 * let's always let through the first entry, at least:
3002 	 */
3003 	if (!cd->rd_dircount)
3004 		goto fail;
3005 	name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8;
3006 	if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
3007 		goto fail;
3008 	cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
3009 
3010 	cd->cookie_offset = cookie_offset;
3011 skip_entry:
3012 	cd->common.err = nfs_ok;
3013 	return 0;
3014 fail:
3015 	xdr_truncate_encode(xdr, start_offset);
3016 	cd->common.err = nfserr;
3017 	return -EINVAL;
3018 }
3019 
3020 static __be32
3021 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
3022 {
3023 	__be32 *p;
3024 
3025 	p = xdr_reserve_space(xdr, sizeof(stateid_t));
3026 	if (!p)
3027 		return nfserr_resource;
3028 	*p++ = cpu_to_be32(sid->si_generation);
3029 	p = xdr_encode_opaque_fixed(p, &sid->si_opaque,
3030 					sizeof(stateid_opaque_t));
3031 	return 0;
3032 }
3033 
3034 static __be32
3035 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
3036 {
3037 	struct xdr_stream *xdr = &resp->xdr;
3038 	__be32 *p;
3039 
3040 	if (!nfserr) {
3041 		p = xdr_reserve_space(xdr, 8);
3042 		if (!p)
3043 			return nfserr_resource;
3044 		*p++ = cpu_to_be32(access->ac_supported);
3045 		*p++ = cpu_to_be32(access->ac_resp_access);
3046 	}
3047 	return nfserr;
3048 }
3049 
3050 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
3051 {
3052 	struct xdr_stream *xdr = &resp->xdr;
3053 	__be32 *p;
3054 
3055 	if (!nfserr) {
3056 		p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 8);
3057 		if (!p)
3058 			return nfserr_resource;
3059 		p = xdr_encode_opaque_fixed(p, bcts->sessionid.data,
3060 						NFS4_MAX_SESSIONID_LEN);
3061 		*p++ = cpu_to_be32(bcts->dir);
3062 		/* Upshifting from TCP to RDMA is not supported */
3063 		*p++ = cpu_to_be32(0);
3064 	}
3065 	return nfserr;
3066 }
3067 
3068 static __be32
3069 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
3070 {
3071 	struct xdr_stream *xdr = &resp->xdr;
3072 
3073 	if (!nfserr)
3074 		nfserr = nfsd4_encode_stateid(xdr, &close->cl_stateid);
3075 
3076 	return nfserr;
3077 }
3078 
3079 
3080 static __be32
3081 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
3082 {
3083 	struct xdr_stream *xdr = &resp->xdr;
3084 	__be32 *p;
3085 
3086 	if (!nfserr) {
3087 		p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3088 		if (!p)
3089 			return nfserr_resource;
3090 		p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
3091 						NFS4_VERIFIER_SIZE);
3092 	}
3093 	return nfserr;
3094 }
3095 
3096 static __be32
3097 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
3098 {
3099 	struct xdr_stream *xdr = &resp->xdr;
3100 	__be32 *p;
3101 
3102 	if (!nfserr) {
3103 		p = xdr_reserve_space(xdr, 20);
3104 		if (!p)
3105 			return nfserr_resource;
3106 		encode_cinfo(p, &create->cr_cinfo);
3107 		nfserr = nfsd4_encode_bitmap(xdr, create->cr_bmval[0],
3108 				create->cr_bmval[1], create->cr_bmval[2]);
3109 	}
3110 	return nfserr;
3111 }
3112 
3113 static __be32
3114 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
3115 {
3116 	struct svc_fh *fhp = getattr->ga_fhp;
3117 	struct xdr_stream *xdr = &resp->xdr;
3118 
3119 	if (nfserr)
3120 		return nfserr;
3121 
3122 	nfserr = nfsd4_encode_fattr(xdr, fhp, fhp->fh_export, fhp->fh_dentry,
3123 				    getattr->ga_bmval,
3124 				    resp->rqstp, 0);
3125 	return nfserr;
3126 }
3127 
3128 static __be32
3129 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
3130 {
3131 	struct xdr_stream *xdr = &resp->xdr;
3132 	struct svc_fh *fhp = *fhpp;
3133 	unsigned int len;
3134 	__be32 *p;
3135 
3136 	if (!nfserr) {
3137 		len = fhp->fh_handle.fh_size;
3138 		p = xdr_reserve_space(xdr, len + 4);
3139 		if (!p)
3140 			return nfserr_resource;
3141 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base, len);
3142 	}
3143 	return nfserr;
3144 }
3145 
3146 /*
3147 * Including all fields other than the name, a LOCK4denied structure requires
3148 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
3149 */
3150 static __be32
3151 nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld)
3152 {
3153 	struct xdr_netobj *conf = &ld->ld_owner;
3154 	__be32 *p;
3155 
3156 again:
3157 	p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len));
3158 	if (!p) {
3159 		/*
3160 		 * Don't fail to return the result just because we can't
3161 		 * return the conflicting open:
3162 		 */
3163 		if (conf->len) {
3164 			kfree(conf->data);
3165 			conf->len = 0;
3166 			conf->data = NULL;
3167 			goto again;
3168 		}
3169 		return nfserr_resource;
3170 	}
3171 	p = xdr_encode_hyper(p, ld->ld_start);
3172 	p = xdr_encode_hyper(p, ld->ld_length);
3173 	*p++ = cpu_to_be32(ld->ld_type);
3174 	if (conf->len) {
3175 		p = xdr_encode_opaque_fixed(p, &ld->ld_clientid, 8);
3176 		p = xdr_encode_opaque(p, conf->data, conf->len);
3177 		kfree(conf->data);
3178 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
3179 		p = xdr_encode_hyper(p, (u64)0); /* clientid */
3180 		*p++ = cpu_to_be32(0); /* length of owner name */
3181 	}
3182 	return nfserr_denied;
3183 }
3184 
3185 static __be32
3186 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
3187 {
3188 	struct xdr_stream *xdr = &resp->xdr;
3189 
3190 	if (!nfserr)
3191 		nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid);
3192 	else if (nfserr == nfserr_denied)
3193 		nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied);
3194 
3195 	return nfserr;
3196 }
3197 
3198 static __be32
3199 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
3200 {
3201 	struct xdr_stream *xdr = &resp->xdr;
3202 
3203 	if (nfserr == nfserr_denied)
3204 		nfsd4_encode_lock_denied(xdr, &lockt->lt_denied);
3205 	return nfserr;
3206 }
3207 
3208 static __be32
3209 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
3210 {
3211 	struct xdr_stream *xdr = &resp->xdr;
3212 
3213 	if (!nfserr)
3214 		nfserr = nfsd4_encode_stateid(xdr, &locku->lu_stateid);
3215 
3216 	return nfserr;
3217 }
3218 
3219 
3220 static __be32
3221 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
3222 {
3223 	struct xdr_stream *xdr = &resp->xdr;
3224 	__be32 *p;
3225 
3226 	if (!nfserr) {
3227 		p = xdr_reserve_space(xdr, 20);
3228 		if (!p)
3229 			return nfserr_resource;
3230 		p = encode_cinfo(p, &link->li_cinfo);
3231 	}
3232 	return nfserr;
3233 }
3234 
3235 
3236 static __be32
3237 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
3238 {
3239 	struct xdr_stream *xdr = &resp->xdr;
3240 	__be32 *p;
3241 
3242 	if (nfserr)
3243 		goto out;
3244 
3245 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
3246 	if (nfserr)
3247 		goto out;
3248 	p = xdr_reserve_space(xdr, 24);
3249 	if (!p)
3250 		return nfserr_resource;
3251 	p = encode_cinfo(p, &open->op_cinfo);
3252 	*p++ = cpu_to_be32(open->op_rflags);
3253 
3254 	nfserr = nfsd4_encode_bitmap(xdr, open->op_bmval[0], open->op_bmval[1],
3255 					open->op_bmval[2]);
3256 	if (nfserr)
3257 		goto out;
3258 
3259 	p = xdr_reserve_space(xdr, 4);
3260 	if (!p)
3261 		return nfserr_resource;
3262 
3263 	*p++ = cpu_to_be32(open->op_delegate_type);
3264 	switch (open->op_delegate_type) {
3265 	case NFS4_OPEN_DELEGATE_NONE:
3266 		break;
3267 	case NFS4_OPEN_DELEGATE_READ:
3268 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3269 		if (nfserr)
3270 			return nfserr;
3271 		p = xdr_reserve_space(xdr, 20);
3272 		if (!p)
3273 			return nfserr_resource;
3274 		*p++ = cpu_to_be32(open->op_recall);
3275 
3276 		/*
3277 		 * TODO: ACE's in delegations
3278 		 */
3279 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3280 		*p++ = cpu_to_be32(0);
3281 		*p++ = cpu_to_be32(0);
3282 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3283 		break;
3284 	case NFS4_OPEN_DELEGATE_WRITE:
3285 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3286 		if (nfserr)
3287 			return nfserr;
3288 		p = xdr_reserve_space(xdr, 32);
3289 		if (!p)
3290 			return nfserr_resource;
3291 		*p++ = cpu_to_be32(0);
3292 
3293 		/*
3294 		 * TODO: space_limit's in delegations
3295 		 */
3296 		*p++ = cpu_to_be32(NFS4_LIMIT_SIZE);
3297 		*p++ = cpu_to_be32(~(u32)0);
3298 		*p++ = cpu_to_be32(~(u32)0);
3299 
3300 		/*
3301 		 * TODO: ACE's in delegations
3302 		 */
3303 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3304 		*p++ = cpu_to_be32(0);
3305 		*p++ = cpu_to_be32(0);
3306 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3307 		break;
3308 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
3309 		switch (open->op_why_no_deleg) {
3310 		case WND4_CONTENTION:
3311 		case WND4_RESOURCE:
3312 			p = xdr_reserve_space(xdr, 8);
3313 			if (!p)
3314 				return nfserr_resource;
3315 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3316 			/* deleg signaling not supported yet: */
3317 			*p++ = cpu_to_be32(0);
3318 			break;
3319 		default:
3320 			p = xdr_reserve_space(xdr, 4);
3321 			if (!p)
3322 				return nfserr_resource;
3323 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3324 		}
3325 		break;
3326 	default:
3327 		BUG();
3328 	}
3329 	/* XXX save filehandle here */
3330 out:
3331 	return nfserr;
3332 }
3333 
3334 static __be32
3335 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
3336 {
3337 	struct xdr_stream *xdr = &resp->xdr;
3338 
3339 	if (!nfserr)
3340 		nfserr = nfsd4_encode_stateid(xdr, &oc->oc_resp_stateid);
3341 
3342 	return nfserr;
3343 }
3344 
3345 static __be32
3346 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
3347 {
3348 	struct xdr_stream *xdr = &resp->xdr;
3349 
3350 	if (!nfserr)
3351 		nfserr = nfsd4_encode_stateid(xdr, &od->od_stateid);
3352 
3353 	return nfserr;
3354 }
3355 
3356 static __be32 nfsd4_encode_splice_read(
3357 				struct nfsd4_compoundres *resp,
3358 				struct nfsd4_read *read,
3359 				struct file *file, unsigned long maxcount)
3360 {
3361 	struct xdr_stream *xdr = &resp->xdr;
3362 	struct xdr_buf *buf = xdr->buf;
3363 	u32 eof;
3364 	long len;
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 	len = maxcount;
3374 	nfserr = nfsd_splice_read(read->rd_rqstp, file,
3375 				  read->rd_offset, &maxcount);
3376 	if (nfserr) {
3377 		/*
3378 		 * nfsd_splice_actor may have already messed with the
3379 		 * page length; reset it so as not to confuse
3380 		 * xdr_truncate_encode:
3381 		 */
3382 		buf->page_len = 0;
3383 		return nfserr;
3384 	}
3385 
3386 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3387 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3388 
3389 	*(p++) = htonl(eof);
3390 	*(p++) = htonl(maxcount);
3391 
3392 	buf->page_len = maxcount;
3393 	buf->len += maxcount;
3394 	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
3395 							/ PAGE_SIZE;
3396 
3397 	/* Use rest of head for padding and remaining ops: */
3398 	buf->tail[0].iov_base = xdr->p;
3399 	buf->tail[0].iov_len = 0;
3400 	xdr->iov = buf->tail;
3401 	if (maxcount&3) {
3402 		int pad = 4 - (maxcount&3);
3403 
3404 		*(xdr->p++) = 0;
3405 
3406 		buf->tail[0].iov_base += maxcount&3;
3407 		buf->tail[0].iov_len = pad;
3408 		buf->len += pad;
3409 	}
3410 
3411 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
3412 				buf->buflen - buf->len);
3413 	buf->buflen = buf->len + space_left;
3414 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
3415 
3416 	return 0;
3417 }
3418 
3419 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
3420 				 struct nfsd4_read *read,
3421 				 struct file *file, unsigned long maxcount)
3422 {
3423 	struct xdr_stream *xdr = &resp->xdr;
3424 	u32 eof;
3425 	int v;
3426 	int starting_len = xdr->buf->len - 8;
3427 	long len;
3428 	int thislen;
3429 	__be32 nfserr;
3430 	__be32 tmp;
3431 	__be32 *p;
3432 	u32 zzz = 0;
3433 	int pad;
3434 
3435 	len = maxcount;
3436 	v = 0;
3437 
3438 	thislen = min_t(long, len, ((void *)xdr->end - (void *)xdr->p));
3439 	p = xdr_reserve_space(xdr, (thislen+3)&~3);
3440 	WARN_ON_ONCE(!p);
3441 	resp->rqstp->rq_vec[v].iov_base = p;
3442 	resp->rqstp->rq_vec[v].iov_len = thislen;
3443 	v++;
3444 	len -= thislen;
3445 
3446 	while (len) {
3447 		thislen = min_t(long, len, PAGE_SIZE);
3448 		p = xdr_reserve_space(xdr, (thislen+3)&~3);
3449 		WARN_ON_ONCE(!p);
3450 		resp->rqstp->rq_vec[v].iov_base = p;
3451 		resp->rqstp->rq_vec[v].iov_len = thislen;
3452 		v++;
3453 		len -= thislen;
3454 	}
3455 	read->rd_vlen = v;
3456 
3457 	len = maxcount;
3458 	nfserr = nfsd_readv(file, read->rd_offset, resp->rqstp->rq_vec,
3459 			read->rd_vlen, &maxcount);
3460 	if (nfserr)
3461 		return nfserr;
3462 	xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3));
3463 
3464 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3465 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3466 
3467 	tmp = htonl(eof);
3468 	write_bytes_to_xdr_buf(xdr->buf, starting_len    , &tmp, 4);
3469 	tmp = htonl(maxcount);
3470 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
3471 
3472 	pad = (maxcount&3) ? 4 - (maxcount&3) : 0;
3473 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 8 + maxcount,
3474 								&zzz, pad);
3475 	return 0;
3476 
3477 }
3478 
3479 static __be32
3480 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
3481 		  struct nfsd4_read *read)
3482 {
3483 	unsigned long maxcount;
3484 	struct xdr_stream *xdr = &resp->xdr;
3485 	struct file *file = read->rd_filp;
3486 	int starting_len = xdr->buf->len;
3487 	struct raparms *ra = NULL;
3488 	__be32 *p;
3489 
3490 	if (nfserr)
3491 		goto out;
3492 
3493 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
3494 	if (!p) {
3495 		WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
3496 		nfserr = nfserr_resource;
3497 		goto out;
3498 	}
3499 	if (resp->xdr.buf->page_len &&
3500 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
3501 		WARN_ON_ONCE(1);
3502 		nfserr = nfserr_resource;
3503 		goto out;
3504 	}
3505 	xdr_commit_encode(xdr);
3506 
3507 	maxcount = svc_max_payload(resp->rqstp);
3508 	maxcount = min_t(unsigned long, maxcount,
3509 			 (xdr->buf->buflen - xdr->buf->len));
3510 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
3511 
3512 	if (read->rd_tmp_file)
3513 		ra = nfsd_init_raparms(file);
3514 
3515 	if (file->f_op->splice_read &&
3516 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
3517 		nfserr = nfsd4_encode_splice_read(resp, read, file, maxcount);
3518 	else
3519 		nfserr = nfsd4_encode_readv(resp, read, file, maxcount);
3520 
3521 	if (ra)
3522 		nfsd_put_raparams(file, ra);
3523 
3524 	if (nfserr)
3525 		xdr_truncate_encode(xdr, starting_len);
3526 
3527 out:
3528 	if (file)
3529 		fput(file);
3530 	return nfserr;
3531 }
3532 
3533 static __be32
3534 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3535 {
3536 	int maxcount;
3537 	__be32 wire_count;
3538 	int zero = 0;
3539 	struct xdr_stream *xdr = &resp->xdr;
3540 	int length_offset = xdr->buf->len;
3541 	__be32 *p;
3542 
3543 	if (nfserr)
3544 		return nfserr;
3545 
3546 	p = xdr_reserve_space(xdr, 4);
3547 	if (!p)
3548 		return nfserr_resource;
3549 	maxcount = PAGE_SIZE;
3550 
3551 	p = xdr_reserve_space(xdr, maxcount);
3552 	if (!p)
3553 		return nfserr_resource;
3554 	/*
3555 	 * XXX: By default, the ->readlink() VFS op will truncate symlinks
3556 	 * if they would overflow the buffer.  Is this kosher in NFSv4?  If
3557 	 * not, one easy fix is: if ->readlink() precisely fills the buffer,
3558 	 * assume that truncation occurred, and return NFS4ERR_RESOURCE.
3559 	 */
3560 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
3561 						(char *)p, &maxcount);
3562 	if (nfserr == nfserr_isdir)
3563 		nfserr = nfserr_inval;
3564 	if (nfserr) {
3565 		xdr_truncate_encode(xdr, length_offset);
3566 		return nfserr;
3567 	}
3568 
3569 	wire_count = htonl(maxcount);
3570 	write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
3571 	xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
3572 	if (maxcount & 3)
3573 		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
3574 						&zero, 4 - (maxcount&3));
3575 	return 0;
3576 }
3577 
3578 static __be32
3579 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3580 {
3581 	int maxcount;
3582 	int bytes_left;
3583 	loff_t offset;
3584 	__be64 wire_offset;
3585 	struct xdr_stream *xdr = &resp->xdr;
3586 	int starting_len = xdr->buf->len;
3587 	__be32 *p;
3588 
3589 	if (nfserr)
3590 		return nfserr;
3591 
3592 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3593 	if (!p)
3594 		return nfserr_resource;
3595 
3596 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3597 	*p++ = cpu_to_be32(0);
3598 	*p++ = cpu_to_be32(0);
3599 	resp->xdr.buf->head[0].iov_len = ((char *)resp->xdr.p)
3600 				- (char *)resp->xdr.buf->head[0].iov_base;
3601 
3602 	/*
3603 	 * Number of bytes left for directory entries allowing for the
3604 	 * final 8 bytes of the readdir and a following failed op:
3605 	 */
3606 	bytes_left = xdr->buf->buflen - xdr->buf->len
3607 			- COMPOUND_ERR_SLACK_SPACE - 8;
3608 	if (bytes_left < 0) {
3609 		nfserr = nfserr_resource;
3610 		goto err_no_verf;
3611 	}
3612 	maxcount = min_t(u32, readdir->rd_maxcount, INT_MAX);
3613 	/*
3614 	 * Note the rfc defines rd_maxcount as the size of the
3615 	 * READDIR4resok structure, which includes the verifier above
3616 	 * and the 8 bytes encoded at the end of this function:
3617 	 */
3618 	if (maxcount < 16) {
3619 		nfserr = nfserr_toosmall;
3620 		goto err_no_verf;
3621 	}
3622 	maxcount = min_t(int, maxcount-16, bytes_left);
3623 
3624 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
3625 	if (!readdir->rd_dircount)
3626 		readdir->rd_dircount = INT_MAX;
3627 
3628 	readdir->xdr = xdr;
3629 	readdir->rd_maxcount = maxcount;
3630 	readdir->common.err = 0;
3631 	readdir->cookie_offset = 0;
3632 
3633 	offset = readdir->rd_cookie;
3634 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3635 			      &offset,
3636 			      &readdir->common, nfsd4_encode_dirent);
3637 	if (nfserr == nfs_ok &&
3638 	    readdir->common.err == nfserr_toosmall &&
3639 	    xdr->buf->len == starting_len + 8) {
3640 		/* nothing encoded; which limit did we hit?: */
3641 		if (maxcount - 16 < bytes_left)
3642 			/* It was the fault of rd_maxcount: */
3643 			nfserr = nfserr_toosmall;
3644 		else
3645 			/* We ran out of buffer space: */
3646 			nfserr = nfserr_resource;
3647 	}
3648 	if (nfserr)
3649 		goto err_no_verf;
3650 
3651 	if (readdir->cookie_offset) {
3652 		wire_offset = cpu_to_be64(offset);
3653 		write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset,
3654 							&wire_offset, 8);
3655 	}
3656 
3657 	p = xdr_reserve_space(xdr, 8);
3658 	if (!p) {
3659 		WARN_ON_ONCE(1);
3660 		goto err_no_verf;
3661 	}
3662 	*p++ = 0;	/* no more entries */
3663 	*p++ = htonl(readdir->common.err == nfserr_eof);
3664 
3665 	return 0;
3666 err_no_verf:
3667 	xdr_truncate_encode(xdr, starting_len);
3668 	return nfserr;
3669 }
3670 
3671 static __be32
3672 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3673 {
3674 	struct xdr_stream *xdr = &resp->xdr;
3675 	__be32 *p;
3676 
3677 	if (!nfserr) {
3678 		p = xdr_reserve_space(xdr, 20);
3679 		if (!p)
3680 			return nfserr_resource;
3681 		p = encode_cinfo(p, &remove->rm_cinfo);
3682 	}
3683 	return nfserr;
3684 }
3685 
3686 static __be32
3687 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3688 {
3689 	struct xdr_stream *xdr = &resp->xdr;
3690 	__be32 *p;
3691 
3692 	if (!nfserr) {
3693 		p = xdr_reserve_space(xdr, 40);
3694 		if (!p)
3695 			return nfserr_resource;
3696 		p = encode_cinfo(p, &rename->rn_sinfo);
3697 		p = encode_cinfo(p, &rename->rn_tinfo);
3698 	}
3699 	return nfserr;
3700 }
3701 
3702 static __be32
3703 nfsd4_do_encode_secinfo(struct xdr_stream *xdr,
3704 			 __be32 nfserr, struct svc_export *exp)
3705 {
3706 	u32 i, nflavs, supported;
3707 	struct exp_flavor_info *flavs;
3708 	struct exp_flavor_info def_flavs[2];
3709 	__be32 *p, *flavorsp;
3710 	static bool report = true;
3711 
3712 	if (nfserr)
3713 		goto out;
3714 	nfserr = nfserr_resource;
3715 	if (exp->ex_nflavors) {
3716 		flavs = exp->ex_flavors;
3717 		nflavs = exp->ex_nflavors;
3718 	} else { /* Handling of some defaults in absence of real secinfo: */
3719 		flavs = def_flavs;
3720 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3721 			nflavs = 2;
3722 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3723 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3724 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3725 			nflavs = 1;
3726 			flavs[0].pseudoflavor
3727 					= svcauth_gss_flavor(exp->ex_client);
3728 		} else {
3729 			nflavs = 1;
3730 			flavs[0].pseudoflavor
3731 					= exp->ex_client->flavour->flavour;
3732 		}
3733 	}
3734 
3735 	supported = 0;
3736 	p = xdr_reserve_space(xdr, 4);
3737 	if (!p)
3738 		goto out;
3739 	flavorsp = p++;		/* to be backfilled later */
3740 
3741 	for (i = 0; i < nflavs; i++) {
3742 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
3743 		struct rpcsec_gss_info info;
3744 
3745 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
3746 			supported++;
3747 			p = xdr_reserve_space(xdr, 4 + 4 +
3748 					      XDR_LEN(info.oid.len) + 4 + 4);
3749 			if (!p)
3750 				goto out;
3751 			*p++ = cpu_to_be32(RPC_AUTH_GSS);
3752 			p = xdr_encode_opaque(p,  info.oid.data, info.oid.len);
3753 			*p++ = cpu_to_be32(info.qop);
3754 			*p++ = cpu_to_be32(info.service);
3755 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
3756 			supported++;
3757 			p = xdr_reserve_space(xdr, 4);
3758 			if (!p)
3759 				goto out;
3760 			*p++ = cpu_to_be32(pf);
3761 		} else {
3762 			if (report)
3763 				pr_warn("NFS: SECINFO: security flavor %u "
3764 					"is not supported\n", pf);
3765 		}
3766 	}
3767 
3768 	if (nflavs != supported)
3769 		report = false;
3770 	*flavorsp = htonl(supported);
3771 	nfserr = 0;
3772 out:
3773 	if (exp)
3774 		exp_put(exp);
3775 	return nfserr;
3776 }
3777 
3778 static __be32
3779 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3780 		     struct nfsd4_secinfo *secinfo)
3781 {
3782 	struct xdr_stream *xdr = &resp->xdr;
3783 
3784 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->si_exp);
3785 }
3786 
3787 static __be32
3788 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3789 		     struct nfsd4_secinfo_no_name *secinfo)
3790 {
3791 	struct xdr_stream *xdr = &resp->xdr;
3792 
3793 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->sin_exp);
3794 }
3795 
3796 /*
3797  * The SETATTR encode routine is special -- it always encodes a bitmap,
3798  * regardless of the error status.
3799  */
3800 static __be32
3801 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3802 {
3803 	struct xdr_stream *xdr = &resp->xdr;
3804 	__be32 *p;
3805 
3806 	p = xdr_reserve_space(xdr, 16);
3807 	if (!p)
3808 		return nfserr_resource;
3809 	if (nfserr) {
3810 		*p++ = cpu_to_be32(3);
3811 		*p++ = cpu_to_be32(0);
3812 		*p++ = cpu_to_be32(0);
3813 		*p++ = cpu_to_be32(0);
3814 	}
3815 	else {
3816 		*p++ = cpu_to_be32(3);
3817 		*p++ = cpu_to_be32(setattr->sa_bmval[0]);
3818 		*p++ = cpu_to_be32(setattr->sa_bmval[1]);
3819 		*p++ = cpu_to_be32(setattr->sa_bmval[2]);
3820 	}
3821 	return nfserr;
3822 }
3823 
3824 static __be32
3825 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3826 {
3827 	struct xdr_stream *xdr = &resp->xdr;
3828 	__be32 *p;
3829 
3830 	if (!nfserr) {
3831 		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
3832 		if (!p)
3833 			return nfserr_resource;
3834 		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
3835 		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
3836 						NFS4_VERIFIER_SIZE);
3837 	}
3838 	else if (nfserr == nfserr_clid_inuse) {
3839 		p = xdr_reserve_space(xdr, 8);
3840 		if (!p)
3841 			return nfserr_resource;
3842 		*p++ = cpu_to_be32(0);
3843 		*p++ = cpu_to_be32(0);
3844 	}
3845 	return nfserr;
3846 }
3847 
3848 static __be32
3849 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3850 {
3851 	struct xdr_stream *xdr = &resp->xdr;
3852 	__be32 *p;
3853 
3854 	if (!nfserr) {
3855 		p = xdr_reserve_space(xdr, 16);
3856 		if (!p)
3857 			return nfserr_resource;
3858 		*p++ = cpu_to_be32(write->wr_bytes_written);
3859 		*p++ = cpu_to_be32(write->wr_how_written);
3860 		p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
3861 							NFS4_VERIFIER_SIZE);
3862 	}
3863 	return nfserr;
3864 }
3865 
3866 static __be32
3867 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
3868 			 struct nfsd4_exchange_id *exid)
3869 {
3870 	struct xdr_stream *xdr = &resp->xdr;
3871 	__be32 *p;
3872 	char *major_id;
3873 	char *server_scope;
3874 	int major_id_sz;
3875 	int server_scope_sz;
3876 	int status = 0;
3877 	uint64_t minor_id = 0;
3878 
3879 	if (nfserr)
3880 		return nfserr;
3881 
3882 	major_id = utsname()->nodename;
3883 	major_id_sz = strlen(major_id);
3884 	server_scope = utsname()->nodename;
3885 	server_scope_sz = strlen(server_scope);
3886 
3887 	p = xdr_reserve_space(xdr,
3888 		8 /* eir_clientid */ +
3889 		4 /* eir_sequenceid */ +
3890 		4 /* eir_flags */ +
3891 		4 /* spr_how */);
3892 	if (!p)
3893 		return nfserr_resource;
3894 
3895 	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
3896 	*p++ = cpu_to_be32(exid->seqid);
3897 	*p++ = cpu_to_be32(exid->flags);
3898 
3899 	*p++ = cpu_to_be32(exid->spa_how);
3900 
3901 	switch (exid->spa_how) {
3902 	case SP4_NONE:
3903 		break;
3904 	case SP4_MACH_CRED:
3905 		/* spo_must_enforce bitmap: */
3906 		status = nfsd4_encode_bitmap(xdr,
3907 					exid->spo_must_enforce[0],
3908 					exid->spo_must_enforce[1],
3909 					exid->spo_must_enforce[2]);
3910 		if (status)
3911 			goto out;
3912 		/* spo_must_allow bitmap: */
3913 		status = nfsd4_encode_bitmap(xdr,
3914 					exid->spo_must_allow[0],
3915 					exid->spo_must_allow[1],
3916 					exid->spo_must_allow[2]);
3917 		if (status)
3918 			goto out;
3919 		break;
3920 	default:
3921 		WARN_ON_ONCE(1);
3922 	}
3923 
3924 	p = xdr_reserve_space(xdr,
3925 		8 /* so_minor_id */ +
3926 		4 /* so_major_id.len */ +
3927 		(XDR_QUADLEN(major_id_sz) * 4) +
3928 		4 /* eir_server_scope.len */ +
3929 		(XDR_QUADLEN(server_scope_sz) * 4) +
3930 		4 /* eir_server_impl_id.count (0) */);
3931 	if (!p)
3932 		return nfserr_resource;
3933 
3934 	/* The server_owner struct */
3935 	p = xdr_encode_hyper(p, minor_id);      /* Minor id */
3936 	/* major id */
3937 	p = xdr_encode_opaque(p, major_id, major_id_sz);
3938 
3939 	/* Server scope */
3940 	p = xdr_encode_opaque(p, server_scope, server_scope_sz);
3941 
3942 	/* Implementation id */
3943 	*p++ = cpu_to_be32(0);	/* zero length nfs_impl_id4 array */
3944 	return 0;
3945 out:
3946 	return status;
3947 }
3948 
3949 static __be32
3950 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
3951 			    struct nfsd4_create_session *sess)
3952 {
3953 	struct xdr_stream *xdr = &resp->xdr;
3954 	__be32 *p;
3955 
3956 	if (nfserr)
3957 		return nfserr;
3958 
3959 	p = xdr_reserve_space(xdr, 24);
3960 	if (!p)
3961 		return nfserr_resource;
3962 	p = xdr_encode_opaque_fixed(p, sess->sessionid.data,
3963 					NFS4_MAX_SESSIONID_LEN);
3964 	*p++ = cpu_to_be32(sess->seqid);
3965 	*p++ = cpu_to_be32(sess->flags);
3966 
3967 	p = xdr_reserve_space(xdr, 28);
3968 	if (!p)
3969 		return nfserr_resource;
3970 	*p++ = cpu_to_be32(0); /* headerpadsz */
3971 	*p++ = cpu_to_be32(sess->fore_channel.maxreq_sz);
3972 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_sz);
3973 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_cached);
3974 	*p++ = cpu_to_be32(sess->fore_channel.maxops);
3975 	*p++ = cpu_to_be32(sess->fore_channel.maxreqs);
3976 	*p++ = cpu_to_be32(sess->fore_channel.nr_rdma_attrs);
3977 
3978 	if (sess->fore_channel.nr_rdma_attrs) {
3979 		p = xdr_reserve_space(xdr, 4);
3980 		if (!p)
3981 			return nfserr_resource;
3982 		*p++ = cpu_to_be32(sess->fore_channel.rdma_attrs);
3983 	}
3984 
3985 	p = xdr_reserve_space(xdr, 28);
3986 	if (!p)
3987 		return nfserr_resource;
3988 	*p++ = cpu_to_be32(0); /* headerpadsz */
3989 	*p++ = cpu_to_be32(sess->back_channel.maxreq_sz);
3990 	*p++ = cpu_to_be32(sess->back_channel.maxresp_sz);
3991 	*p++ = cpu_to_be32(sess->back_channel.maxresp_cached);
3992 	*p++ = cpu_to_be32(sess->back_channel.maxops);
3993 	*p++ = cpu_to_be32(sess->back_channel.maxreqs);
3994 	*p++ = cpu_to_be32(sess->back_channel.nr_rdma_attrs);
3995 
3996 	if (sess->back_channel.nr_rdma_attrs) {
3997 		p = xdr_reserve_space(xdr, 4);
3998 		if (!p)
3999 			return nfserr_resource;
4000 		*p++ = cpu_to_be32(sess->back_channel.rdma_attrs);
4001 	}
4002 	return 0;
4003 }
4004 
4005 static __be32
4006 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
4007 		      struct nfsd4_sequence *seq)
4008 {
4009 	struct xdr_stream *xdr = &resp->xdr;
4010 	__be32 *p;
4011 
4012 	if (nfserr)
4013 		return nfserr;
4014 
4015 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 20);
4016 	if (!p)
4017 		return nfserr_resource;
4018 	p = xdr_encode_opaque_fixed(p, seq->sessionid.data,
4019 					NFS4_MAX_SESSIONID_LEN);
4020 	*p++ = cpu_to_be32(seq->seqid);
4021 	*p++ = cpu_to_be32(seq->slotid);
4022 	/* Note slotid's are numbered from zero: */
4023 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_highest_slotid */
4024 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_target_highest_slotid */
4025 	*p++ = cpu_to_be32(seq->status_flags);
4026 
4027 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
4028 	return 0;
4029 }
4030 
4031 static __be32
4032 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
4033 			  struct nfsd4_test_stateid *test_stateid)
4034 {
4035 	struct xdr_stream *xdr = &resp->xdr;
4036 	struct nfsd4_test_stateid_id *stateid, *next;
4037 	__be32 *p;
4038 
4039 	if (nfserr)
4040 		return nfserr;
4041 
4042 	p = xdr_reserve_space(xdr, 4 + (4 * test_stateid->ts_num_ids));
4043 	if (!p)
4044 		return nfserr_resource;
4045 	*p++ = htonl(test_stateid->ts_num_ids);
4046 
4047 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
4048 		*p++ = stateid->ts_id_status;
4049 	}
4050 
4051 	return nfserr;
4052 }
4053 
4054 #ifdef CONFIG_NFSD_PNFS
4055 static __be32
4056 nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
4057 		struct nfsd4_getdeviceinfo *gdev)
4058 {
4059 	struct xdr_stream *xdr = &resp->xdr;
4060 	const struct nfsd4_layout_ops *ops =
4061 		nfsd4_layout_ops[gdev->gd_layout_type];
4062 	u32 starting_len = xdr->buf->len, needed_len;
4063 	__be32 *p;
4064 
4065 	dprintk("%s: err %d\n", __func__, nfserr);
4066 	if (nfserr)
4067 		goto out;
4068 
4069 	nfserr = nfserr_resource;
4070 	p = xdr_reserve_space(xdr, 4);
4071 	if (!p)
4072 		goto out;
4073 
4074 	*p++ = cpu_to_be32(gdev->gd_layout_type);
4075 
4076 	/* If maxcount is 0 then just update notifications */
4077 	if (gdev->gd_maxcount != 0) {
4078 		nfserr = ops->encode_getdeviceinfo(xdr, gdev);
4079 		if (nfserr) {
4080 			/*
4081 			 * We don't bother to burden the layout drivers with
4082 			 * enforcing gd_maxcount, just tell the client to
4083 			 * come back with a bigger buffer if it's not enough.
4084 			 */
4085 			if (xdr->buf->len + 4 > gdev->gd_maxcount)
4086 				goto toosmall;
4087 			goto out;
4088 		}
4089 	}
4090 
4091 	nfserr = nfserr_resource;
4092 	if (gdev->gd_notify_types) {
4093 		p = xdr_reserve_space(xdr, 4 + 4);
4094 		if (!p)
4095 			goto out;
4096 		*p++ = cpu_to_be32(1);			/* bitmap length */
4097 		*p++ = cpu_to_be32(gdev->gd_notify_types);
4098 	} else {
4099 		p = xdr_reserve_space(xdr, 4);
4100 		if (!p)
4101 			goto out;
4102 		*p++ = 0;
4103 	}
4104 
4105 	nfserr = 0;
4106 out:
4107 	kfree(gdev->gd_device);
4108 	dprintk("%s: done: %d\n", __func__, be32_to_cpu(nfserr));
4109 	return nfserr;
4110 
4111 toosmall:
4112 	dprintk("%s: maxcount too small\n", __func__);
4113 	needed_len = xdr->buf->len + 4 /* notifications */;
4114 	xdr_truncate_encode(xdr, starting_len);
4115 	p = xdr_reserve_space(xdr, 4);
4116 	if (!p) {
4117 		nfserr = nfserr_resource;
4118 	} else {
4119 		*p++ = cpu_to_be32(needed_len);
4120 		nfserr = nfserr_toosmall;
4121 	}
4122 	goto out;
4123 }
4124 
4125 static __be32
4126 nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr,
4127 		struct nfsd4_layoutget *lgp)
4128 {
4129 	struct xdr_stream *xdr = &resp->xdr;
4130 	const struct nfsd4_layout_ops *ops =
4131 		nfsd4_layout_ops[lgp->lg_layout_type];
4132 	__be32 *p;
4133 
4134 	dprintk("%s: err %d\n", __func__, nfserr);
4135 	if (nfserr)
4136 		goto out;
4137 
4138 	nfserr = nfserr_resource;
4139 	p = xdr_reserve_space(xdr, 36 + sizeof(stateid_opaque_t));
4140 	if (!p)
4141 		goto out;
4142 
4143 	*p++ = cpu_to_be32(1);	/* we always set return-on-close */
4144 	*p++ = cpu_to_be32(lgp->lg_sid.si_generation);
4145 	p = xdr_encode_opaque_fixed(p, &lgp->lg_sid.si_opaque,
4146 				    sizeof(stateid_opaque_t));
4147 
4148 	*p++ = cpu_to_be32(1);	/* we always return a single layout */
4149 	p = xdr_encode_hyper(p, lgp->lg_seg.offset);
4150 	p = xdr_encode_hyper(p, lgp->lg_seg.length);
4151 	*p++ = cpu_to_be32(lgp->lg_seg.iomode);
4152 	*p++ = cpu_to_be32(lgp->lg_layout_type);
4153 
4154 	nfserr = ops->encode_layoutget(xdr, lgp);
4155 out:
4156 	kfree(lgp->lg_content);
4157 	return nfserr;
4158 }
4159 
4160 static __be32
4161 nfsd4_encode_layoutcommit(struct nfsd4_compoundres *resp, __be32 nfserr,
4162 			  struct nfsd4_layoutcommit *lcp)
4163 {
4164 	struct xdr_stream *xdr = &resp->xdr;
4165 	__be32 *p;
4166 
4167 	if (nfserr)
4168 		return nfserr;
4169 
4170 	p = xdr_reserve_space(xdr, 4);
4171 	if (!p)
4172 		return nfserr_resource;
4173 	*p++ = cpu_to_be32(lcp->lc_size_chg);
4174 	if (lcp->lc_size_chg) {
4175 		p = xdr_reserve_space(xdr, 8);
4176 		if (!p)
4177 			return nfserr_resource;
4178 		p = xdr_encode_hyper(p, lcp->lc_newsize);
4179 	}
4180 
4181 	return nfs_ok;
4182 }
4183 
4184 static __be32
4185 nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
4186 		struct nfsd4_layoutreturn *lrp)
4187 {
4188 	struct xdr_stream *xdr = &resp->xdr;
4189 	__be32 *p;
4190 
4191 	if (nfserr)
4192 		return nfserr;
4193 
4194 	p = xdr_reserve_space(xdr, 4);
4195 	if (!p)
4196 		return nfserr_resource;
4197 	*p++ = cpu_to_be32(lrp->lrs_present);
4198 	if (lrp->lrs_present)
4199 		return nfsd4_encode_stateid(xdr, &lrp->lr_sid);
4200 	return nfs_ok;
4201 }
4202 #endif /* CONFIG_NFSD_PNFS */
4203 
4204 static __be32
4205 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
4206 		  struct nfsd4_seek *seek)
4207 {
4208 	__be32 *p;
4209 
4210 	if (nfserr)
4211 		return nfserr;
4212 
4213 	p = xdr_reserve_space(&resp->xdr, 4 + 8);
4214 	*p++ = cpu_to_be32(seek->seek_eof);
4215 	p = xdr_encode_hyper(p, seek->seek_pos);
4216 
4217 	return nfserr;
4218 }
4219 
4220 static __be32
4221 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
4222 {
4223 	return nfserr;
4224 }
4225 
4226 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
4227 
4228 /*
4229  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
4230  * since we don't need to filter out obsolete ops as this is
4231  * done in the decoding phase.
4232  */
4233 static nfsd4_enc nfsd4_enc_ops[] = {
4234 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
4235 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
4236 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
4237 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
4238 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
4239 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4240 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
4241 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
4242 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
4243 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
4244 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
4245 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
4246 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
4247 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
4248 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4249 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
4250 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
4251 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
4252 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
4253 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4254 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
4255 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4256 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
4257 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
4258 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
4259 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
4260 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
4261 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
4262 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
4263 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
4264 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
4265 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
4266 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
4267 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
4268 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4269 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
4270 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
4271 
4272 	/* NFSv4.1 operations */
4273 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
4274 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
4275 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
4276 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
4277 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
4278 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
4279 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4280 #ifdef CONFIG_NFSD_PNFS
4281 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_getdeviceinfo,
4282 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4283 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_layoutcommit,
4284 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_layoutget,
4285 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_layoutreturn,
4286 #else
4287 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
4288 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4289 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
4290 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
4291 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4292 #endif
4293 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
4294 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
4295 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
4296 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
4297 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4298 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
4299 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
4300 
4301 	/* NFSv4.2 operations */
4302 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4303 	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_noop,
4304 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
4305 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4306 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
4307 	[OP_LAYOUTERROR]	= (nfsd4_enc)nfsd4_encode_noop,
4308 	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,
4309 	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,
4310 	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_noop,
4311 	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_noop,
4312 	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,
4313 	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,
4314 	[OP_CLONE]		= (nfsd4_enc)nfsd4_encode_noop,
4315 };
4316 
4317 /*
4318  * Calculate whether we still have space to encode repsize bytes.
4319  * There are two considerations:
4320  *     - For NFS versions >=4.1, the size of the reply must stay within
4321  *       session limits
4322  *     - For all NFS versions, we must stay within limited preallocated
4323  *       buffer space.
4324  *
4325  * This is called before the operation is processed, so can only provide
4326  * an upper estimate.  For some nonidempotent operations (such as
4327  * getattr), it's not necessarily a problem if that estimate is wrong,
4328  * as we can fail it after processing without significant side effects.
4329  */
4330 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
4331 {
4332 	struct xdr_buf *buf = &resp->rqstp->rq_res;
4333 	struct nfsd4_slot *slot = resp->cstate.slot;
4334 
4335 	if (buf->len + respsize <= buf->buflen)
4336 		return nfs_ok;
4337 	if (!nfsd4_has_session(&resp->cstate))
4338 		return nfserr_resource;
4339 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
4340 		WARN_ON_ONCE(1);
4341 		return nfserr_rep_too_big_to_cache;
4342 	}
4343 	return nfserr_rep_too_big;
4344 }
4345 
4346 void
4347 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
4348 {
4349 	struct xdr_stream *xdr = &resp->xdr;
4350 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
4351 	struct svc_rqst *rqstp = resp->rqstp;
4352 	int post_err_offset;
4353 	nfsd4_enc encoder;
4354 	__be32 *p;
4355 
4356 	p = xdr_reserve_space(xdr, 8);
4357 	if (!p) {
4358 		WARN_ON_ONCE(1);
4359 		return;
4360 	}
4361 	*p++ = cpu_to_be32(op->opnum);
4362 	post_err_offset = xdr->buf->len;
4363 
4364 	if (op->opnum == OP_ILLEGAL)
4365 		goto status;
4366 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
4367 	       !nfsd4_enc_ops[op->opnum]);
4368 	encoder = nfsd4_enc_ops[op->opnum];
4369 	op->status = encoder(resp, op->status, &op->u);
4370 	xdr_commit_encode(xdr);
4371 
4372 	/* nfsd4_check_resp_size guarantees enough room for error status */
4373 	if (!op->status) {
4374 		int space_needed = 0;
4375 		if (!nfsd4_last_compound_op(rqstp))
4376 			space_needed = COMPOUND_ERR_SLACK_SPACE;
4377 		op->status = nfsd4_check_resp_size(resp, space_needed);
4378 	}
4379 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
4380 		struct nfsd4_slot *slot = resp->cstate.slot;
4381 
4382 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
4383 			op->status = nfserr_rep_too_big_to_cache;
4384 		else
4385 			op->status = nfserr_rep_too_big;
4386 	}
4387 	if (op->status == nfserr_resource ||
4388 	    op->status == nfserr_rep_too_big ||
4389 	    op->status == nfserr_rep_too_big_to_cache) {
4390 		/*
4391 		 * The operation may have already been encoded or
4392 		 * partially encoded.  No op returns anything additional
4393 		 * in the case of one of these three errors, so we can
4394 		 * just truncate back to after the status.  But it's a
4395 		 * bug if we had to do this on a non-idempotent op:
4396 		 */
4397 		warn_on_nonidempotent_op(op);
4398 		xdr_truncate_encode(xdr, post_err_offset);
4399 	}
4400 	if (so) {
4401 		int len = xdr->buf->len - post_err_offset;
4402 
4403 		so->so_replay.rp_status = op->status;
4404 		so->so_replay.rp_buflen = len;
4405 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
4406 						so->so_replay.rp_buf, len);
4407 	}
4408 status:
4409 	/* Note that op->status is already in network byte order: */
4410 	write_bytes_to_xdr_buf(xdr->buf, post_err_offset - 4, &op->status, 4);
4411 }
4412 
4413 /*
4414  * Encode the reply stored in the stateowner reply cache
4415  *
4416  * XDR note: do not encode rp->rp_buflen: the buffer contains the
4417  * previously sent already encoded operation.
4418  */
4419 void
4420 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
4421 {
4422 	__be32 *p;
4423 	struct nfs4_replay *rp = op->replay;
4424 
4425 	BUG_ON(!rp);
4426 
4427 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
4428 	if (!p) {
4429 		WARN_ON_ONCE(1);
4430 		return;
4431 	}
4432 	*p++ = cpu_to_be32(op->opnum);
4433 	*p++ = rp->rp_status;  /* already xdr'ed */
4434 
4435 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
4436 }
4437 
4438 int
4439 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
4440 {
4441         return xdr_ressize_check(rqstp, p);
4442 }
4443 
4444 int nfsd4_release_compoundargs(void *rq, __be32 *p, void *resp)
4445 {
4446 	struct svc_rqst *rqstp = rq;
4447 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4448 
4449 	if (args->ops != args->iops) {
4450 		kfree(args->ops);
4451 		args->ops = args->iops;
4452 	}
4453 	kfree(args->tmpp);
4454 	args->tmpp = NULL;
4455 	while (args->to_free) {
4456 		struct svcxdr_tmpbuf *tb = args->to_free;
4457 		args->to_free = tb->next;
4458 		kfree(tb);
4459 	}
4460 	return 1;
4461 }
4462 
4463 int
4464 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundargs *args)
4465 {
4466 	if (rqstp->rq_arg.head[0].iov_len % 4) {
4467 		/* client is nuts */
4468 		dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)",
4469 			__func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid));
4470 		return 0;
4471 	}
4472 	args->p = p;
4473 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
4474 	args->pagelist = rqstp->rq_arg.pages;
4475 	args->pagelen = rqstp->rq_arg.page_len;
4476 	args->tmpp = NULL;
4477 	args->to_free = NULL;
4478 	args->ops = args->iops;
4479 	args->rqstp = rqstp;
4480 
4481 	return !nfsd4_decode_compound(args);
4482 }
4483 
4484 int
4485 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundres *resp)
4486 {
4487 	/*
4488 	 * All that remains is to write the tag and operation count...
4489 	 */
4490 	struct xdr_buf *buf = resp->xdr.buf;
4491 
4492 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
4493 				 buf->tail[0].iov_len);
4494 
4495 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
4496 
4497 	p = resp->tagp;
4498 	*p++ = htonl(resp->taglen);
4499 	memcpy(p, resp->tag, resp->taglen);
4500 	p += XDR_QUADLEN(resp->taglen);
4501 	*p++ = htonl(resp->opcnt);
4502 
4503 	nfsd4_sequence_done(resp);
4504 	return 1;
4505 }
4506 
4507 /*
4508  * Local variables:
4509  *  c-basic-offset: 8
4510  * End:
4511  */
4512