xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision ae213c44)
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 const u32 nfsd_suppattrs[3][3] = {
61 	{NFSD4_SUPPORTED_ATTRS_WORD0,
62 	 NFSD4_SUPPORTED_ATTRS_WORD1,
63 	 NFSD4_SUPPORTED_ATTRS_WORD2},
64 
65 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
66 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
67 	 NFSD4_1_SUPPORTED_ATTRS_WORD2},
68 
69 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
70 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
71 	 NFSD4_2_SUPPORTED_ATTRS_WORD2},
72 };
73 
74 /*
75  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
76  * directory in order to indicate to the client that a filesystem boundary is present
77  * We use a fixed fsid for a referral
78  */
79 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
80 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
81 
82 static __be32
83 check_filename(char *str, int len)
84 {
85 	int i;
86 
87 	if (len == 0)
88 		return nfserr_inval;
89 	if (isdotent(str, len))
90 		return nfserr_badname;
91 	for (i = 0; i < len; i++)
92 		if (str[i] == '/')
93 			return nfserr_badname;
94 	return 0;
95 }
96 
97 #define DECODE_HEAD				\
98 	__be32 *p;				\
99 	__be32 status
100 #define DECODE_TAIL				\
101 	status = 0;				\
102 out:						\
103 	return status;				\
104 xdr_error:					\
105 	dprintk("NFSD: xdr error (%s:%d)\n",	\
106 			__FILE__, __LINE__);	\
107 	status = nfserr_bad_xdr;		\
108 	goto out
109 
110 #define READMEM(x,nbytes) do {			\
111 	x = (char *)p;				\
112 	p += XDR_QUADLEN(nbytes);		\
113 } while (0)
114 #define SAVEMEM(x,nbytes) do {			\
115 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
116  		savemem(argp, p, nbytes) :	\
117  		(char *)p)) {			\
118 		dprintk("NFSD: xdr error (%s:%d)\n", \
119 				__FILE__, __LINE__); \
120 		goto xdr_error;			\
121 		}				\
122 	p += XDR_QUADLEN(nbytes);		\
123 } while (0)
124 #define COPYMEM(x,nbytes) do {			\
125 	memcpy((x), p, nbytes);			\
126 	p += XDR_QUADLEN(nbytes);		\
127 } while (0)
128 
129 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
130 #define READ_BUF(nbytes)  do {			\
131 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
132 		p = argp->p;			\
133 		argp->p += XDR_QUADLEN(nbytes);	\
134 	} else if (!(p = read_buf(argp, nbytes))) { \
135 		dprintk("NFSD: xdr error (%s:%d)\n", \
136 				__FILE__, __LINE__); \
137 		goto xdr_error;			\
138 	}					\
139 } while (0)
140 
141 static void next_decode_page(struct nfsd4_compoundargs *argp)
142 {
143 	argp->p = page_address(argp->pagelist[0]);
144 	argp->pagelist++;
145 	if (argp->pagelen < PAGE_SIZE) {
146 		argp->end = argp->p + XDR_QUADLEN(argp->pagelen);
147 		argp->pagelen = 0;
148 	} else {
149 		argp->end = argp->p + (PAGE_SIZE>>2);
150 		argp->pagelen -= PAGE_SIZE;
151 	}
152 }
153 
154 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
155 {
156 	/* We want more bytes than seem to be available.
157 	 * Maybe we need a new page, maybe we have just run out
158 	 */
159 	unsigned int avail = (char *)argp->end - (char *)argp->p;
160 	__be32 *p;
161 
162 	if (argp->pagelen == 0) {
163 		struct kvec *vec = &argp->rqstp->rq_arg.tail[0];
164 
165 		if (!argp->tail) {
166 			argp->tail = true;
167 			avail = vec->iov_len;
168 			argp->p = vec->iov_base;
169 			argp->end = vec->iov_base + avail;
170 		}
171 
172 		if (avail < nbytes)
173 			return NULL;
174 
175 		p = argp->p;
176 		argp->p += XDR_QUADLEN(nbytes);
177 		return p;
178 	}
179 
180 	if (avail + argp->pagelen < nbytes)
181 		return NULL;
182 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
183 		return NULL;
184 	/* ok, we can do it with the current plus the next page */
185 	if (nbytes <= sizeof(argp->tmp))
186 		p = argp->tmp;
187 	else {
188 		kfree(argp->tmpp);
189 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
190 		if (!p)
191 			return NULL;
192 
193 	}
194 	/*
195 	 * The following memcpy is safe because read_buf is always
196 	 * called with nbytes > avail, and the two cases above both
197 	 * guarantee p points to at least nbytes bytes.
198 	 */
199 	memcpy(p, argp->p, avail);
200 	next_decode_page(argp);
201 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
202 	argp->p += XDR_QUADLEN(nbytes - avail);
203 	return p;
204 }
205 
206 static int zero_clientid(clientid_t *clid)
207 {
208 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
209 }
210 
211 /**
212  * svcxdr_tmpalloc - allocate memory to be freed after compound processing
213  * @argp: NFSv4 compound argument structure
214  * @p: pointer to be freed (with kfree())
215  *
216  * Marks @p to be freed when processing the compound operation
217  * described in @argp finishes.
218  */
219 static void *
220 svcxdr_tmpalloc(struct nfsd4_compoundargs *argp, u32 len)
221 {
222 	struct svcxdr_tmpbuf *tb;
223 
224 	tb = kmalloc(sizeof(*tb) + len, GFP_KERNEL);
225 	if (!tb)
226 		return NULL;
227 	tb->next = argp->to_free;
228 	argp->to_free = tb;
229 	return tb->buf;
230 }
231 
232 /*
233  * For xdr strings that need to be passed to other kernel api's
234  * as null-terminated strings.
235  *
236  * Note null-terminating in place usually isn't safe since the
237  * buffer might end on a page boundary.
238  */
239 static char *
240 svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len)
241 {
242 	char *p = svcxdr_tmpalloc(argp, len + 1);
243 
244 	if (!p)
245 		return NULL;
246 	memcpy(p, buf, len);
247 	p[len] = '\0';
248 	return p;
249 }
250 
251 /**
252  * savemem - duplicate a chunk of memory for later processing
253  * @argp: NFSv4 compound argument structure to be freed with
254  * @p: pointer to be duplicated
255  * @nbytes: length to be duplicated
256  *
257  * Returns a pointer to a copy of @nbytes bytes of memory at @p
258  * that are preserved until processing of the NFSv4 compound
259  * operation described by @argp finishes.
260  */
261 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
262 {
263 	void *ret;
264 
265 	ret = svcxdr_tmpalloc(argp, nbytes);
266 	if (!ret)
267 		return NULL;
268 	memcpy(ret, p, nbytes);
269 	return ret;
270 }
271 
272 /*
273  * We require the high 32 bits of 'seconds' to be 0, and
274  * we ignore all 32 bits of 'nseconds'.
275  */
276 static __be32
277 nfsd4_decode_time(struct nfsd4_compoundargs *argp, struct timespec *tv)
278 {
279 	DECODE_HEAD;
280 	u64 sec;
281 
282 	READ_BUF(12);
283 	p = xdr_decode_hyper(p, &sec);
284 	tv->tv_sec = sec;
285 	tv->tv_nsec = be32_to_cpup(p++);
286 	if (tv->tv_nsec >= (u32)1000000000)
287 		return nfserr_inval;
288 
289 	DECODE_TAIL;
290 }
291 
292 static __be32
293 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
294 {
295 	u32 bmlen;
296 	DECODE_HEAD;
297 
298 	bmval[0] = 0;
299 	bmval[1] = 0;
300 	bmval[2] = 0;
301 
302 	READ_BUF(4);
303 	bmlen = be32_to_cpup(p++);
304 	if (bmlen > 1000)
305 		goto xdr_error;
306 
307 	READ_BUF(bmlen << 2);
308 	if (bmlen > 0)
309 		bmval[0] = be32_to_cpup(p++);
310 	if (bmlen > 1)
311 		bmval[1] = be32_to_cpup(p++);
312 	if (bmlen > 2)
313 		bmval[2] = be32_to_cpup(p++);
314 
315 	DECODE_TAIL;
316 }
317 
318 static __be32
319 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
320 		   struct iattr *iattr, struct nfs4_acl **acl,
321 		   struct xdr_netobj *label, int *umask)
322 {
323 	struct timespec ts;
324 	int expected_len, len = 0;
325 	u32 dummy32;
326 	char *buf;
327 
328 	DECODE_HEAD;
329 	iattr->ia_valid = 0;
330 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
331 		return status;
332 
333 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
334 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
335 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2) {
336 		if (nfsd_attrs_supported(argp->minorversion, bmval))
337 			return nfserr_inval;
338 		return nfserr_attrnotsupp;
339 	}
340 
341 	READ_BUF(4);
342 	expected_len = be32_to_cpup(p++);
343 
344 	if (bmval[0] & FATTR4_WORD0_SIZE) {
345 		READ_BUF(8);
346 		len += 8;
347 		p = xdr_decode_hyper(p, &iattr->ia_size);
348 		iattr->ia_valid |= ATTR_SIZE;
349 	}
350 	if (bmval[0] & FATTR4_WORD0_ACL) {
351 		u32 nace;
352 		struct nfs4_ace *ace;
353 
354 		READ_BUF(4); len += 4;
355 		nace = be32_to_cpup(p++);
356 
357 		if (nace > NFS4_ACL_MAX)
358 			return nfserr_fbig;
359 
360 		*acl = svcxdr_tmpalloc(argp, nfs4_acl_bytes(nace));
361 		if (*acl == NULL)
362 			return nfserr_jukebox;
363 
364 		(*acl)->naces = nace;
365 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
366 			READ_BUF(16); len += 16;
367 			ace->type = be32_to_cpup(p++);
368 			ace->flag = be32_to_cpup(p++);
369 			ace->access_mask = be32_to_cpup(p++);
370 			dummy32 = be32_to_cpup(p++);
371 			READ_BUF(dummy32);
372 			len += XDR_QUADLEN(dummy32) << 2;
373 			READMEM(buf, dummy32);
374 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
375 			status = nfs_ok;
376 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
377 				;
378 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
379 				status = nfsd_map_name_to_gid(argp->rqstp,
380 						buf, dummy32, &ace->who_gid);
381 			else
382 				status = nfsd_map_name_to_uid(argp->rqstp,
383 						buf, dummy32, &ace->who_uid);
384 			if (status)
385 				return status;
386 		}
387 	} else
388 		*acl = NULL;
389 	if (bmval[1] & FATTR4_WORD1_MODE) {
390 		READ_BUF(4);
391 		len += 4;
392 		iattr->ia_mode = be32_to_cpup(p++);
393 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
394 		iattr->ia_valid |= ATTR_MODE;
395 	}
396 	if (bmval[1] & FATTR4_WORD1_OWNER) {
397 		READ_BUF(4);
398 		len += 4;
399 		dummy32 = be32_to_cpup(p++);
400 		READ_BUF(dummy32);
401 		len += (XDR_QUADLEN(dummy32) << 2);
402 		READMEM(buf, dummy32);
403 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
404 			return status;
405 		iattr->ia_valid |= ATTR_UID;
406 	}
407 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
408 		READ_BUF(4);
409 		len += 4;
410 		dummy32 = be32_to_cpup(p++);
411 		READ_BUF(dummy32);
412 		len += (XDR_QUADLEN(dummy32) << 2);
413 		READMEM(buf, dummy32);
414 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
415 			return status;
416 		iattr->ia_valid |= ATTR_GID;
417 	}
418 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
419 		READ_BUF(4);
420 		len += 4;
421 		dummy32 = be32_to_cpup(p++);
422 		switch (dummy32) {
423 		case NFS4_SET_TO_CLIENT_TIME:
424 			len += 12;
425 			status = nfsd4_decode_time(argp, &ts);
426 			iattr->ia_atime = timespec_to_timespec64(ts);
427 			if (status)
428 				return status;
429 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
430 			break;
431 		case NFS4_SET_TO_SERVER_TIME:
432 			iattr->ia_valid |= ATTR_ATIME;
433 			break;
434 		default:
435 			goto xdr_error;
436 		}
437 	}
438 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
439 		READ_BUF(4);
440 		len += 4;
441 		dummy32 = be32_to_cpup(p++);
442 		switch (dummy32) {
443 		case NFS4_SET_TO_CLIENT_TIME:
444 			len += 12;
445 			status = nfsd4_decode_time(argp, &ts);
446 			iattr->ia_mtime = timespec_to_timespec64(ts);
447 			if (status)
448 				return status;
449 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
450 			break;
451 		case NFS4_SET_TO_SERVER_TIME:
452 			iattr->ia_valid |= ATTR_MTIME;
453 			break;
454 		default:
455 			goto xdr_error;
456 		}
457 	}
458 
459 	label->len = 0;
460 	if (IS_ENABLED(CONFIG_NFSD_V4_SECURITY_LABEL) &&
461 	    bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
462 		READ_BUF(4);
463 		len += 4;
464 		dummy32 = be32_to_cpup(p++); /* lfs: we don't use it */
465 		READ_BUF(4);
466 		len += 4;
467 		dummy32 = be32_to_cpup(p++); /* pi: we don't use it either */
468 		READ_BUF(4);
469 		len += 4;
470 		dummy32 = be32_to_cpup(p++);
471 		READ_BUF(dummy32);
472 		if (dummy32 > NFS4_MAXLABELLEN)
473 			return nfserr_badlabel;
474 		len += (XDR_QUADLEN(dummy32) << 2);
475 		READMEM(buf, dummy32);
476 		label->len = dummy32;
477 		label->data = svcxdr_dupstr(argp, buf, dummy32);
478 		if (!label->data)
479 			return nfserr_jukebox;
480 	}
481 	if (bmval[2] & FATTR4_WORD2_MODE_UMASK) {
482 		if (!umask)
483 			goto xdr_error;
484 		READ_BUF(8);
485 		len += 8;
486 		dummy32 = be32_to_cpup(p++);
487 		iattr->ia_mode = dummy32 & (S_IFMT | S_IALLUGO);
488 		dummy32 = be32_to_cpup(p++);
489 		*umask = dummy32 & S_IRWXUGO;
490 		iattr->ia_valid |= ATTR_MODE;
491 	}
492 	if (len != expected_len)
493 		goto xdr_error;
494 
495 	DECODE_TAIL;
496 }
497 
498 static __be32
499 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
500 {
501 	DECODE_HEAD;
502 
503 	READ_BUF(sizeof(stateid_t));
504 	sid->si_generation = be32_to_cpup(p++);
505 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
506 
507 	DECODE_TAIL;
508 }
509 
510 static __be32
511 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
512 {
513 	DECODE_HEAD;
514 
515 	READ_BUF(4);
516 	access->ac_req_access = be32_to_cpup(p++);
517 
518 	DECODE_TAIL;
519 }
520 
521 static __be32 nfsd4_decode_cb_sec(struct nfsd4_compoundargs *argp, struct nfsd4_cb_sec *cbs)
522 {
523 	DECODE_HEAD;
524 	struct user_namespace *userns = nfsd_user_namespace(argp->rqstp);
525 	u32 dummy, uid, gid;
526 	char *machine_name;
527 	int i;
528 	int nr_secflavs;
529 
530 	/* callback_sec_params4 */
531 	READ_BUF(4);
532 	nr_secflavs = be32_to_cpup(p++);
533 	if (nr_secflavs)
534 		cbs->flavor = (u32)(-1);
535 	else
536 		/* Is this legal? Be generous, take it to mean AUTH_NONE: */
537 		cbs->flavor = 0;
538 	for (i = 0; i < nr_secflavs; ++i) {
539 		READ_BUF(4);
540 		dummy = be32_to_cpup(p++);
541 		switch (dummy) {
542 		case RPC_AUTH_NULL:
543 			/* Nothing to read */
544 			if (cbs->flavor == (u32)(-1))
545 				cbs->flavor = RPC_AUTH_NULL;
546 			break;
547 		case RPC_AUTH_UNIX:
548 			READ_BUF(8);
549 			/* stamp */
550 			dummy = be32_to_cpup(p++);
551 
552 			/* machine name */
553 			dummy = be32_to_cpup(p++);
554 			READ_BUF(dummy);
555 			SAVEMEM(machine_name, dummy);
556 
557 			/* uid, gid */
558 			READ_BUF(8);
559 			uid = be32_to_cpup(p++);
560 			gid = be32_to_cpup(p++);
561 
562 			/* more gids */
563 			READ_BUF(4);
564 			dummy = be32_to_cpup(p++);
565 			READ_BUF(dummy * 4);
566 			if (cbs->flavor == (u32)(-1)) {
567 				kuid_t kuid = make_kuid(userns, uid);
568 				kgid_t kgid = make_kgid(userns, gid);
569 				if (uid_valid(kuid) && gid_valid(kgid)) {
570 					cbs->uid = kuid;
571 					cbs->gid = kgid;
572 					cbs->flavor = RPC_AUTH_UNIX;
573 				} else {
574 					dprintk("RPC_AUTH_UNIX with invalid"
575 						"uid or gid ignoring!\n");
576 				}
577 			}
578 			break;
579 		case RPC_AUTH_GSS:
580 			dprintk("RPC_AUTH_GSS callback secflavor "
581 				"not supported!\n");
582 			READ_BUF(8);
583 			/* gcbp_service */
584 			dummy = be32_to_cpup(p++);
585 			/* gcbp_handle_from_server */
586 			dummy = be32_to_cpup(p++);
587 			READ_BUF(dummy);
588 			p += XDR_QUADLEN(dummy);
589 			/* gcbp_handle_from_client */
590 			READ_BUF(4);
591 			dummy = be32_to_cpup(p++);
592 			READ_BUF(dummy);
593 			break;
594 		default:
595 			dprintk("Illegal callback secflavor\n");
596 			return nfserr_inval;
597 		}
598 	}
599 	DECODE_TAIL;
600 }
601 
602 static __be32 nfsd4_decode_backchannel_ctl(struct nfsd4_compoundargs *argp, struct nfsd4_backchannel_ctl *bc)
603 {
604 	DECODE_HEAD;
605 
606 	READ_BUF(4);
607 	bc->bc_cb_program = be32_to_cpup(p++);
608 	nfsd4_decode_cb_sec(argp, &bc->bc_cb_sec);
609 
610 	DECODE_TAIL;
611 }
612 
613 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
614 {
615 	DECODE_HEAD;
616 
617 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
618 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
619 	bcts->dir = be32_to_cpup(p++);
620 	/* XXX: skipping ctsa_use_conn_in_rdma_mode.  Perhaps Tom Tucker
621 	 * could help us figure out we should be using it. */
622 	DECODE_TAIL;
623 }
624 
625 static __be32
626 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
627 {
628 	DECODE_HEAD;
629 
630 	READ_BUF(4);
631 	close->cl_seqid = be32_to_cpup(p++);
632 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
633 
634 	DECODE_TAIL;
635 }
636 
637 
638 static __be32
639 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
640 {
641 	DECODE_HEAD;
642 
643 	READ_BUF(12);
644 	p = xdr_decode_hyper(p, &commit->co_offset);
645 	commit->co_count = be32_to_cpup(p++);
646 
647 	DECODE_TAIL;
648 }
649 
650 static __be32
651 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
652 {
653 	DECODE_HEAD;
654 
655 	READ_BUF(4);
656 	create->cr_type = be32_to_cpup(p++);
657 	switch (create->cr_type) {
658 	case NF4LNK:
659 		READ_BUF(4);
660 		create->cr_datalen = be32_to_cpup(p++);
661 		READ_BUF(create->cr_datalen);
662 		create->cr_data = svcxdr_dupstr(argp, p, create->cr_datalen);
663 		if (!create->cr_data)
664 			return nfserr_jukebox;
665 		break;
666 	case NF4BLK:
667 	case NF4CHR:
668 		READ_BUF(8);
669 		create->cr_specdata1 = be32_to_cpup(p++);
670 		create->cr_specdata2 = be32_to_cpup(p++);
671 		break;
672 	case NF4SOCK:
673 	case NF4FIFO:
674 	case NF4DIR:
675 	default:
676 		break;
677 	}
678 
679 	READ_BUF(4);
680 	create->cr_namelen = be32_to_cpup(p++);
681 	READ_BUF(create->cr_namelen);
682 	SAVEMEM(create->cr_name, create->cr_namelen);
683 	if ((status = check_filename(create->cr_name, create->cr_namelen)))
684 		return status;
685 
686 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
687 				    &create->cr_acl, &create->cr_label,
688 				    &create->cr_umask);
689 	if (status)
690 		goto out;
691 
692 	DECODE_TAIL;
693 }
694 
695 static inline __be32
696 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
697 {
698 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
699 }
700 
701 static inline __be32
702 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
703 {
704 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
705 }
706 
707 static __be32
708 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
709 {
710 	DECODE_HEAD;
711 
712 	READ_BUF(4);
713 	link->li_namelen = be32_to_cpup(p++);
714 	READ_BUF(link->li_namelen);
715 	SAVEMEM(link->li_name, link->li_namelen);
716 	if ((status = check_filename(link->li_name, link->li_namelen)))
717 		return status;
718 
719 	DECODE_TAIL;
720 }
721 
722 static __be32
723 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
724 {
725 	DECODE_HEAD;
726 
727 	/*
728 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
729 	*/
730 	READ_BUF(28);
731 	lock->lk_type = be32_to_cpup(p++);
732 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
733 		goto xdr_error;
734 	lock->lk_reclaim = be32_to_cpup(p++);
735 	p = xdr_decode_hyper(p, &lock->lk_offset);
736 	p = xdr_decode_hyper(p, &lock->lk_length);
737 	lock->lk_is_new = be32_to_cpup(p++);
738 
739 	if (lock->lk_is_new) {
740 		READ_BUF(4);
741 		lock->lk_new_open_seqid = be32_to_cpup(p++);
742 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
743 		if (status)
744 			return status;
745 		READ_BUF(8 + sizeof(clientid_t));
746 		lock->lk_new_lock_seqid = be32_to_cpup(p++);
747 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
748 		lock->lk_new_owner.len = be32_to_cpup(p++);
749 		READ_BUF(lock->lk_new_owner.len);
750 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
751 	} else {
752 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
753 		if (status)
754 			return status;
755 		READ_BUF(4);
756 		lock->lk_old_lock_seqid = be32_to_cpup(p++);
757 	}
758 
759 	DECODE_TAIL;
760 }
761 
762 static __be32
763 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
764 {
765 	DECODE_HEAD;
766 
767 	READ_BUF(32);
768 	lockt->lt_type = be32_to_cpup(p++);
769 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
770 		goto xdr_error;
771 	p = xdr_decode_hyper(p, &lockt->lt_offset);
772 	p = xdr_decode_hyper(p, &lockt->lt_length);
773 	COPYMEM(&lockt->lt_clientid, 8);
774 	lockt->lt_owner.len = be32_to_cpup(p++);
775 	READ_BUF(lockt->lt_owner.len);
776 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
777 
778 	DECODE_TAIL;
779 }
780 
781 static __be32
782 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
783 {
784 	DECODE_HEAD;
785 
786 	READ_BUF(8);
787 	locku->lu_type = be32_to_cpup(p++);
788 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
789 		goto xdr_error;
790 	locku->lu_seqid = be32_to_cpup(p++);
791 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
792 	if (status)
793 		return status;
794 	READ_BUF(16);
795 	p = xdr_decode_hyper(p, &locku->lu_offset);
796 	p = xdr_decode_hyper(p, &locku->lu_length);
797 
798 	DECODE_TAIL;
799 }
800 
801 static __be32
802 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
803 {
804 	DECODE_HEAD;
805 
806 	READ_BUF(4);
807 	lookup->lo_len = be32_to_cpup(p++);
808 	READ_BUF(lookup->lo_len);
809 	SAVEMEM(lookup->lo_name, lookup->lo_len);
810 	if ((status = check_filename(lookup->lo_name, lookup->lo_len)))
811 		return status;
812 
813 	DECODE_TAIL;
814 }
815 
816 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
817 {
818 	__be32 *p;
819 	u32 w;
820 
821 	READ_BUF(4);
822 	w = be32_to_cpup(p++);
823 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
824 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
825 	if (deleg_when)
826 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
827 
828 	switch (w & NFS4_SHARE_ACCESS_MASK) {
829 	case NFS4_SHARE_ACCESS_READ:
830 	case NFS4_SHARE_ACCESS_WRITE:
831 	case NFS4_SHARE_ACCESS_BOTH:
832 		break;
833 	default:
834 		return nfserr_bad_xdr;
835 	}
836 	w &= ~NFS4_SHARE_ACCESS_MASK;
837 	if (!w)
838 		return nfs_ok;
839 	if (!argp->minorversion)
840 		return nfserr_bad_xdr;
841 	switch (w & NFS4_SHARE_WANT_MASK) {
842 	case NFS4_SHARE_WANT_NO_PREFERENCE:
843 	case NFS4_SHARE_WANT_READ_DELEG:
844 	case NFS4_SHARE_WANT_WRITE_DELEG:
845 	case NFS4_SHARE_WANT_ANY_DELEG:
846 	case NFS4_SHARE_WANT_NO_DELEG:
847 	case NFS4_SHARE_WANT_CANCEL:
848 		break;
849 	default:
850 		return nfserr_bad_xdr;
851 	}
852 	w &= ~NFS4_SHARE_WANT_MASK;
853 	if (!w)
854 		return nfs_ok;
855 
856 	if (!deleg_when)	/* open_downgrade */
857 		return nfserr_inval;
858 	switch (w) {
859 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
860 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
861 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
862 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
863 		return nfs_ok;
864 	}
865 xdr_error:
866 	return nfserr_bad_xdr;
867 }
868 
869 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
870 {
871 	__be32 *p;
872 
873 	READ_BUF(4);
874 	*x = be32_to_cpup(p++);
875 	/* Note: unlinke access bits, deny bits may be zero. */
876 	if (*x & ~NFS4_SHARE_DENY_BOTH)
877 		return nfserr_bad_xdr;
878 	return nfs_ok;
879 xdr_error:
880 	return nfserr_bad_xdr;
881 }
882 
883 static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
884 {
885 	__be32 *p;
886 
887 	READ_BUF(4);
888 	o->len = be32_to_cpup(p++);
889 
890 	if (o->len == 0 || o->len > NFS4_OPAQUE_LIMIT)
891 		return nfserr_bad_xdr;
892 
893 	READ_BUF(o->len);
894 	SAVEMEM(o->data, o->len);
895 	return nfs_ok;
896 xdr_error:
897 	return nfserr_bad_xdr;
898 }
899 
900 static __be32
901 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
902 {
903 	DECODE_HEAD;
904 	u32 dummy;
905 
906 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
907 	open->op_iattr.ia_valid = 0;
908 	open->op_openowner = NULL;
909 
910 	open->op_xdr_error = 0;
911 	/* seqid, share_access, share_deny, clientid, ownerlen */
912 	READ_BUF(4);
913 	open->op_seqid = be32_to_cpup(p++);
914 	/* decode, yet ignore deleg_when until supported */
915 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
916 					   &open->op_deleg_want, &dummy);
917 	if (status)
918 		goto xdr_error;
919 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
920 	if (status)
921 		goto xdr_error;
922 	READ_BUF(sizeof(clientid_t));
923 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
924 	status = nfsd4_decode_opaque(argp, &open->op_owner);
925 	if (status)
926 		goto xdr_error;
927 	READ_BUF(4);
928 	open->op_create = be32_to_cpup(p++);
929 	switch (open->op_create) {
930 	case NFS4_OPEN_NOCREATE:
931 		break;
932 	case NFS4_OPEN_CREATE:
933 		READ_BUF(4);
934 		open->op_createmode = be32_to_cpup(p++);
935 		switch (open->op_createmode) {
936 		case NFS4_CREATE_UNCHECKED:
937 		case NFS4_CREATE_GUARDED:
938 			status = nfsd4_decode_fattr(argp, open->op_bmval,
939 				&open->op_iattr, &open->op_acl, &open->op_label,
940 				&open->op_umask);
941 			if (status)
942 				goto out;
943 			break;
944 		case NFS4_CREATE_EXCLUSIVE:
945 			READ_BUF(NFS4_VERIFIER_SIZE);
946 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
947 			break;
948 		case NFS4_CREATE_EXCLUSIVE4_1:
949 			if (argp->minorversion < 1)
950 				goto xdr_error;
951 			READ_BUF(NFS4_VERIFIER_SIZE);
952 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
953 			status = nfsd4_decode_fattr(argp, open->op_bmval,
954 				&open->op_iattr, &open->op_acl, &open->op_label,
955 				&open->op_umask);
956 			if (status)
957 				goto out;
958 			break;
959 		default:
960 			goto xdr_error;
961 		}
962 		break;
963 	default:
964 		goto xdr_error;
965 	}
966 
967 	/* open_claim */
968 	READ_BUF(4);
969 	open->op_claim_type = be32_to_cpup(p++);
970 	switch (open->op_claim_type) {
971 	case NFS4_OPEN_CLAIM_NULL:
972 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
973 		READ_BUF(4);
974 		open->op_fname.len = be32_to_cpup(p++);
975 		READ_BUF(open->op_fname.len);
976 		SAVEMEM(open->op_fname.data, open->op_fname.len);
977 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
978 			return status;
979 		break;
980 	case NFS4_OPEN_CLAIM_PREVIOUS:
981 		READ_BUF(4);
982 		open->op_delegate_type = be32_to_cpup(p++);
983 		break;
984 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
985 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
986 		if (status)
987 			return status;
988 		READ_BUF(4);
989 		open->op_fname.len = be32_to_cpup(p++);
990 		READ_BUF(open->op_fname.len);
991 		SAVEMEM(open->op_fname.data, open->op_fname.len);
992 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
993 			return status;
994 		break;
995 	case NFS4_OPEN_CLAIM_FH:
996 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
997 		if (argp->minorversion < 1)
998 			goto xdr_error;
999 		/* void */
1000 		break;
1001 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
1002 		if (argp->minorversion < 1)
1003 			goto xdr_error;
1004 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
1005 		if (status)
1006 			return status;
1007 		break;
1008 	default:
1009 		goto xdr_error;
1010 	}
1011 
1012 	DECODE_TAIL;
1013 }
1014 
1015 static __be32
1016 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
1017 {
1018 	DECODE_HEAD;
1019 
1020 	if (argp->minorversion >= 1)
1021 		return nfserr_notsupp;
1022 
1023 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
1024 	if (status)
1025 		return status;
1026 	READ_BUF(4);
1027 	open_conf->oc_seqid = be32_to_cpup(p++);
1028 
1029 	DECODE_TAIL;
1030 }
1031 
1032 static __be32
1033 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
1034 {
1035 	DECODE_HEAD;
1036 
1037 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
1038 	if (status)
1039 		return status;
1040 	READ_BUF(4);
1041 	open_down->od_seqid = be32_to_cpup(p++);
1042 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
1043 					   &open_down->od_deleg_want, NULL);
1044 	if (status)
1045 		return status;
1046 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
1047 	if (status)
1048 		return status;
1049 	DECODE_TAIL;
1050 }
1051 
1052 static __be32
1053 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
1054 {
1055 	DECODE_HEAD;
1056 
1057 	READ_BUF(4);
1058 	putfh->pf_fhlen = be32_to_cpup(p++);
1059 	if (putfh->pf_fhlen > NFS4_FHSIZE)
1060 		goto xdr_error;
1061 	READ_BUF(putfh->pf_fhlen);
1062 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
1063 
1064 	DECODE_TAIL;
1065 }
1066 
1067 static __be32
1068 nfsd4_decode_putpubfh(struct nfsd4_compoundargs *argp, void *p)
1069 {
1070 	if (argp->minorversion == 0)
1071 		return nfs_ok;
1072 	return nfserr_notsupp;
1073 }
1074 
1075 static __be32
1076 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
1077 {
1078 	DECODE_HEAD;
1079 
1080 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
1081 	if (status)
1082 		return status;
1083 	READ_BUF(12);
1084 	p = xdr_decode_hyper(p, &read->rd_offset);
1085 	read->rd_length = be32_to_cpup(p++);
1086 
1087 	DECODE_TAIL;
1088 }
1089 
1090 static __be32
1091 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
1092 {
1093 	DECODE_HEAD;
1094 
1095 	READ_BUF(24);
1096 	p = xdr_decode_hyper(p, &readdir->rd_cookie);
1097 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
1098 	readdir->rd_dircount = be32_to_cpup(p++);
1099 	readdir->rd_maxcount = be32_to_cpup(p++);
1100 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
1101 		goto out;
1102 
1103 	DECODE_TAIL;
1104 }
1105 
1106 static __be32
1107 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
1108 {
1109 	DECODE_HEAD;
1110 
1111 	READ_BUF(4);
1112 	remove->rm_namelen = be32_to_cpup(p++);
1113 	READ_BUF(remove->rm_namelen);
1114 	SAVEMEM(remove->rm_name, remove->rm_namelen);
1115 	if ((status = check_filename(remove->rm_name, remove->rm_namelen)))
1116 		return status;
1117 
1118 	DECODE_TAIL;
1119 }
1120 
1121 static __be32
1122 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
1123 {
1124 	DECODE_HEAD;
1125 
1126 	READ_BUF(4);
1127 	rename->rn_snamelen = be32_to_cpup(p++);
1128 	READ_BUF(rename->rn_snamelen);
1129 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1130 	READ_BUF(4);
1131 	rename->rn_tnamelen = be32_to_cpup(p++);
1132 	READ_BUF(rename->rn_tnamelen);
1133 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1134 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1135 		return status;
1136 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1137 		return status;
1138 
1139 	DECODE_TAIL;
1140 }
1141 
1142 static __be32
1143 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1144 {
1145 	DECODE_HEAD;
1146 
1147 	if (argp->minorversion >= 1)
1148 		return nfserr_notsupp;
1149 
1150 	READ_BUF(sizeof(clientid_t));
1151 	COPYMEM(clientid, sizeof(clientid_t));
1152 
1153 	DECODE_TAIL;
1154 }
1155 
1156 static __be32
1157 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1158 		     struct nfsd4_secinfo *secinfo)
1159 {
1160 	DECODE_HEAD;
1161 
1162 	READ_BUF(4);
1163 	secinfo->si_namelen = be32_to_cpup(p++);
1164 	READ_BUF(secinfo->si_namelen);
1165 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1166 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1167 	if (status)
1168 		return status;
1169 	DECODE_TAIL;
1170 }
1171 
1172 static __be32
1173 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1174 		     struct nfsd4_secinfo_no_name *sin)
1175 {
1176 	DECODE_HEAD;
1177 
1178 	READ_BUF(4);
1179 	sin->sin_style = be32_to_cpup(p++);
1180 	DECODE_TAIL;
1181 }
1182 
1183 static __be32
1184 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1185 {
1186 	__be32 status;
1187 
1188 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1189 	if (status)
1190 		return status;
1191 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1192 				  &setattr->sa_acl, &setattr->sa_label, NULL);
1193 }
1194 
1195 static __be32
1196 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1197 {
1198 	DECODE_HEAD;
1199 
1200 	if (argp->minorversion >= 1)
1201 		return nfserr_notsupp;
1202 
1203 	READ_BUF(NFS4_VERIFIER_SIZE);
1204 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1205 
1206 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1207 	if (status)
1208 		return nfserr_bad_xdr;
1209 	READ_BUF(8);
1210 	setclientid->se_callback_prog = be32_to_cpup(p++);
1211 	setclientid->se_callback_netid_len = be32_to_cpup(p++);
1212 	READ_BUF(setclientid->se_callback_netid_len);
1213 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1214 	READ_BUF(4);
1215 	setclientid->se_callback_addr_len = be32_to_cpup(p++);
1216 
1217 	READ_BUF(setclientid->se_callback_addr_len);
1218 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1219 	READ_BUF(4);
1220 	setclientid->se_callback_ident = be32_to_cpup(p++);
1221 
1222 	DECODE_TAIL;
1223 }
1224 
1225 static __be32
1226 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1227 {
1228 	DECODE_HEAD;
1229 
1230 	if (argp->minorversion >= 1)
1231 		return nfserr_notsupp;
1232 
1233 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1234 	COPYMEM(&scd_c->sc_clientid, 8);
1235 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1236 
1237 	DECODE_TAIL;
1238 }
1239 
1240 /* Also used for NVERIFY */
1241 static __be32
1242 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1243 {
1244 	DECODE_HEAD;
1245 
1246 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1247 		goto out;
1248 
1249 	/* For convenience's sake, we compare raw xdr'd attributes in
1250 	 * nfsd4_proc_verify */
1251 
1252 	READ_BUF(4);
1253 	verify->ve_attrlen = be32_to_cpup(p++);
1254 	READ_BUF(verify->ve_attrlen);
1255 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1256 
1257 	DECODE_TAIL;
1258 }
1259 
1260 static __be32
1261 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1262 {
1263 	int avail;
1264 	int len;
1265 	DECODE_HEAD;
1266 
1267 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1268 	if (status)
1269 		return status;
1270 	READ_BUF(16);
1271 	p = xdr_decode_hyper(p, &write->wr_offset);
1272 	write->wr_stable_how = be32_to_cpup(p++);
1273 	if (write->wr_stable_how > NFS_FILE_SYNC)
1274 		goto xdr_error;
1275 	write->wr_buflen = be32_to_cpup(p++);
1276 
1277 	/* Sorry .. no magic macros for this.. *
1278 	 * READ_BUF(write->wr_buflen);
1279 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1280 	 */
1281 	avail = (char*)argp->end - (char*)argp->p;
1282 	if (avail + argp->pagelen < write->wr_buflen) {
1283 		dprintk("NFSD: xdr error (%s:%d)\n",
1284 				__FILE__, __LINE__);
1285 		goto xdr_error;
1286 	}
1287 	write->wr_head.iov_base = p;
1288 	write->wr_head.iov_len = avail;
1289 	write->wr_pagelist = argp->pagelist;
1290 
1291 	len = XDR_QUADLEN(write->wr_buflen) << 2;
1292 	if (len >= avail) {
1293 		int pages;
1294 
1295 		len -= avail;
1296 
1297 		pages = len >> PAGE_SHIFT;
1298 		argp->pagelist += pages;
1299 		argp->pagelen -= pages * PAGE_SIZE;
1300 		len -= pages * PAGE_SIZE;
1301 
1302 		next_decode_page(argp);
1303 	}
1304 	argp->p += XDR_QUADLEN(len);
1305 
1306 	DECODE_TAIL;
1307 }
1308 
1309 static __be32
1310 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1311 {
1312 	DECODE_HEAD;
1313 
1314 	if (argp->minorversion >= 1)
1315 		return nfserr_notsupp;
1316 
1317 	READ_BUF(12);
1318 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1319 	rlockowner->rl_owner.len = be32_to_cpup(p++);
1320 	READ_BUF(rlockowner->rl_owner.len);
1321 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1322 
1323 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1324 		return nfserr_inval;
1325 	DECODE_TAIL;
1326 }
1327 
1328 static __be32
1329 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1330 			 struct nfsd4_exchange_id *exid)
1331 {
1332 	int dummy, tmp;
1333 	DECODE_HEAD;
1334 
1335 	READ_BUF(NFS4_VERIFIER_SIZE);
1336 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1337 
1338 	status = nfsd4_decode_opaque(argp, &exid->clname);
1339 	if (status)
1340 		return nfserr_bad_xdr;
1341 
1342 	READ_BUF(4);
1343 	exid->flags = be32_to_cpup(p++);
1344 
1345 	/* Ignore state_protect4_a */
1346 	READ_BUF(4);
1347 	exid->spa_how = be32_to_cpup(p++);
1348 	switch (exid->spa_how) {
1349 	case SP4_NONE:
1350 		break;
1351 	case SP4_MACH_CRED:
1352 		/* spo_must_enforce */
1353 		status = nfsd4_decode_bitmap(argp,
1354 					exid->spo_must_enforce);
1355 		if (status)
1356 			goto out;
1357 		/* spo_must_allow */
1358 		status = nfsd4_decode_bitmap(argp, exid->spo_must_allow);
1359 		if (status)
1360 			goto out;
1361 		break;
1362 	case SP4_SSV:
1363 		/* ssp_ops */
1364 		READ_BUF(4);
1365 		dummy = be32_to_cpup(p++);
1366 		READ_BUF(dummy * 4);
1367 		p += dummy;
1368 
1369 		READ_BUF(4);
1370 		dummy = be32_to_cpup(p++);
1371 		READ_BUF(dummy * 4);
1372 		p += dummy;
1373 
1374 		/* ssp_hash_algs<> */
1375 		READ_BUF(4);
1376 		tmp = be32_to_cpup(p++);
1377 		while (tmp--) {
1378 			READ_BUF(4);
1379 			dummy = be32_to_cpup(p++);
1380 			READ_BUF(dummy);
1381 			p += XDR_QUADLEN(dummy);
1382 		}
1383 
1384 		/* ssp_encr_algs<> */
1385 		READ_BUF(4);
1386 		tmp = be32_to_cpup(p++);
1387 		while (tmp--) {
1388 			READ_BUF(4);
1389 			dummy = be32_to_cpup(p++);
1390 			READ_BUF(dummy);
1391 			p += XDR_QUADLEN(dummy);
1392 		}
1393 
1394 		/* ignore ssp_window and ssp_num_gss_handles: */
1395 		READ_BUF(8);
1396 		break;
1397 	default:
1398 		goto xdr_error;
1399 	}
1400 
1401 	/* Ignore Implementation ID */
1402 	READ_BUF(4);    /* nfs_impl_id4 array length */
1403 	dummy = be32_to_cpup(p++);
1404 
1405 	if (dummy > 1)
1406 		goto xdr_error;
1407 
1408 	if (dummy == 1) {
1409 		/* nii_domain */
1410 		READ_BUF(4);
1411 		dummy = be32_to_cpup(p++);
1412 		READ_BUF(dummy);
1413 		p += XDR_QUADLEN(dummy);
1414 
1415 		/* nii_name */
1416 		READ_BUF(4);
1417 		dummy = be32_to_cpup(p++);
1418 		READ_BUF(dummy);
1419 		p += XDR_QUADLEN(dummy);
1420 
1421 		/* nii_date */
1422 		READ_BUF(12);
1423 		p += 3;
1424 	}
1425 	DECODE_TAIL;
1426 }
1427 
1428 static __be32
1429 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1430 			    struct nfsd4_create_session *sess)
1431 {
1432 	DECODE_HEAD;
1433 	u32 dummy;
1434 
1435 	READ_BUF(16);
1436 	COPYMEM(&sess->clientid, 8);
1437 	sess->seqid = be32_to_cpup(p++);
1438 	sess->flags = be32_to_cpup(p++);
1439 
1440 	/* Fore channel attrs */
1441 	READ_BUF(28);
1442 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1443 	sess->fore_channel.maxreq_sz = be32_to_cpup(p++);
1444 	sess->fore_channel.maxresp_sz = be32_to_cpup(p++);
1445 	sess->fore_channel.maxresp_cached = be32_to_cpup(p++);
1446 	sess->fore_channel.maxops = be32_to_cpup(p++);
1447 	sess->fore_channel.maxreqs = be32_to_cpup(p++);
1448 	sess->fore_channel.nr_rdma_attrs = be32_to_cpup(p++);
1449 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1450 		READ_BUF(4);
1451 		sess->fore_channel.rdma_attrs = be32_to_cpup(p++);
1452 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1453 		dprintk("Too many fore channel attr bitmaps!\n");
1454 		goto xdr_error;
1455 	}
1456 
1457 	/* Back channel attrs */
1458 	READ_BUF(28);
1459 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1460 	sess->back_channel.maxreq_sz = be32_to_cpup(p++);
1461 	sess->back_channel.maxresp_sz = be32_to_cpup(p++);
1462 	sess->back_channel.maxresp_cached = be32_to_cpup(p++);
1463 	sess->back_channel.maxops = be32_to_cpup(p++);
1464 	sess->back_channel.maxreqs = be32_to_cpup(p++);
1465 	sess->back_channel.nr_rdma_attrs = be32_to_cpup(p++);
1466 	if (sess->back_channel.nr_rdma_attrs == 1) {
1467 		READ_BUF(4);
1468 		sess->back_channel.rdma_attrs = be32_to_cpup(p++);
1469 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1470 		dprintk("Too many back channel attr bitmaps!\n");
1471 		goto xdr_error;
1472 	}
1473 
1474 	READ_BUF(4);
1475 	sess->callback_prog = be32_to_cpup(p++);
1476 	nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1477 	DECODE_TAIL;
1478 }
1479 
1480 static __be32
1481 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1482 			     struct nfsd4_destroy_session *destroy_session)
1483 {
1484 	DECODE_HEAD;
1485 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1486 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1487 
1488 	DECODE_TAIL;
1489 }
1490 
1491 static __be32
1492 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1493 			  struct nfsd4_free_stateid *free_stateid)
1494 {
1495 	DECODE_HEAD;
1496 
1497 	READ_BUF(sizeof(stateid_t));
1498 	free_stateid->fr_stateid.si_generation = be32_to_cpup(p++);
1499 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1500 
1501 	DECODE_TAIL;
1502 }
1503 
1504 static __be32
1505 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1506 		      struct nfsd4_sequence *seq)
1507 {
1508 	DECODE_HEAD;
1509 
1510 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1511 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1512 	seq->seqid = be32_to_cpup(p++);
1513 	seq->slotid = be32_to_cpup(p++);
1514 	seq->maxslots = be32_to_cpup(p++);
1515 	seq->cachethis = be32_to_cpup(p++);
1516 
1517 	DECODE_TAIL;
1518 }
1519 
1520 static __be32
1521 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1522 {
1523 	int i;
1524 	__be32 *p, status;
1525 	struct nfsd4_test_stateid_id *stateid;
1526 
1527 	READ_BUF(4);
1528 	test_stateid->ts_num_ids = ntohl(*p++);
1529 
1530 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1531 
1532 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1533 		stateid = svcxdr_tmpalloc(argp, sizeof(*stateid));
1534 		if (!stateid) {
1535 			status = nfserrno(-ENOMEM);
1536 			goto out;
1537 		}
1538 
1539 		INIT_LIST_HEAD(&stateid->ts_id_list);
1540 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1541 
1542 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1543 		if (status)
1544 			goto out;
1545 	}
1546 
1547 	status = 0;
1548 out:
1549 	return status;
1550 xdr_error:
1551 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1552 	status = nfserr_bad_xdr;
1553 	goto out;
1554 }
1555 
1556 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1557 {
1558 	DECODE_HEAD;
1559 
1560 	READ_BUF(8);
1561 	COPYMEM(&dc->clientid, 8);
1562 
1563 	DECODE_TAIL;
1564 }
1565 
1566 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1567 {
1568 	DECODE_HEAD;
1569 
1570 	READ_BUF(4);
1571 	rc->rca_one_fs = be32_to_cpup(p++);
1572 
1573 	DECODE_TAIL;
1574 }
1575 
1576 #ifdef CONFIG_NFSD_PNFS
1577 static __be32
1578 nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp,
1579 		struct nfsd4_getdeviceinfo *gdev)
1580 {
1581 	DECODE_HEAD;
1582 	u32 num, i;
1583 
1584 	READ_BUF(sizeof(struct nfsd4_deviceid) + 3 * 4);
1585 	COPYMEM(&gdev->gd_devid, sizeof(struct nfsd4_deviceid));
1586 	gdev->gd_layout_type = be32_to_cpup(p++);
1587 	gdev->gd_maxcount = be32_to_cpup(p++);
1588 	num = be32_to_cpup(p++);
1589 	if (num) {
1590 		if (num > 1000)
1591 			goto xdr_error;
1592 		READ_BUF(4 * num);
1593 		gdev->gd_notify_types = be32_to_cpup(p++);
1594 		for (i = 1; i < num; i++) {
1595 			if (be32_to_cpup(p++)) {
1596 				status = nfserr_inval;
1597 				goto out;
1598 			}
1599 		}
1600 	}
1601 	DECODE_TAIL;
1602 }
1603 
1604 static __be32
1605 nfsd4_decode_layoutget(struct nfsd4_compoundargs *argp,
1606 		struct nfsd4_layoutget *lgp)
1607 {
1608 	DECODE_HEAD;
1609 
1610 	READ_BUF(36);
1611 	lgp->lg_signal = be32_to_cpup(p++);
1612 	lgp->lg_layout_type = be32_to_cpup(p++);
1613 	lgp->lg_seg.iomode = be32_to_cpup(p++);
1614 	p = xdr_decode_hyper(p, &lgp->lg_seg.offset);
1615 	p = xdr_decode_hyper(p, &lgp->lg_seg.length);
1616 	p = xdr_decode_hyper(p, &lgp->lg_minlength);
1617 
1618 	status = nfsd4_decode_stateid(argp, &lgp->lg_sid);
1619 	if (status)
1620 		return status;
1621 
1622 	READ_BUF(4);
1623 	lgp->lg_maxcount = be32_to_cpup(p++);
1624 
1625 	DECODE_TAIL;
1626 }
1627 
1628 static __be32
1629 nfsd4_decode_layoutcommit(struct nfsd4_compoundargs *argp,
1630 		struct nfsd4_layoutcommit *lcp)
1631 {
1632 	DECODE_HEAD;
1633 	u32 timechange;
1634 
1635 	READ_BUF(20);
1636 	p = xdr_decode_hyper(p, &lcp->lc_seg.offset);
1637 	p = xdr_decode_hyper(p, &lcp->lc_seg.length);
1638 	lcp->lc_reclaim = be32_to_cpup(p++);
1639 
1640 	status = nfsd4_decode_stateid(argp, &lcp->lc_sid);
1641 	if (status)
1642 		return status;
1643 
1644 	READ_BUF(4);
1645 	lcp->lc_newoffset = be32_to_cpup(p++);
1646 	if (lcp->lc_newoffset) {
1647 		READ_BUF(8);
1648 		p = xdr_decode_hyper(p, &lcp->lc_last_wr);
1649 	} else
1650 		lcp->lc_last_wr = 0;
1651 	READ_BUF(4);
1652 	timechange = be32_to_cpup(p++);
1653 	if (timechange) {
1654 		status = nfsd4_decode_time(argp, &lcp->lc_mtime);
1655 		if (status)
1656 			return status;
1657 	} else {
1658 		lcp->lc_mtime.tv_nsec = UTIME_NOW;
1659 	}
1660 	READ_BUF(8);
1661 	lcp->lc_layout_type = be32_to_cpup(p++);
1662 
1663 	/*
1664 	 * Save the layout update in XDR format and let the layout driver deal
1665 	 * with it later.
1666 	 */
1667 	lcp->lc_up_len = be32_to_cpup(p++);
1668 	if (lcp->lc_up_len > 0) {
1669 		READ_BUF(lcp->lc_up_len);
1670 		READMEM(lcp->lc_up_layout, lcp->lc_up_len);
1671 	}
1672 
1673 	DECODE_TAIL;
1674 }
1675 
1676 static __be32
1677 nfsd4_decode_layoutreturn(struct nfsd4_compoundargs *argp,
1678 		struct nfsd4_layoutreturn *lrp)
1679 {
1680 	DECODE_HEAD;
1681 
1682 	READ_BUF(16);
1683 	lrp->lr_reclaim = be32_to_cpup(p++);
1684 	lrp->lr_layout_type = be32_to_cpup(p++);
1685 	lrp->lr_seg.iomode = be32_to_cpup(p++);
1686 	lrp->lr_return_type = be32_to_cpup(p++);
1687 	if (lrp->lr_return_type == RETURN_FILE) {
1688 		READ_BUF(16);
1689 		p = xdr_decode_hyper(p, &lrp->lr_seg.offset);
1690 		p = xdr_decode_hyper(p, &lrp->lr_seg.length);
1691 
1692 		status = nfsd4_decode_stateid(argp, &lrp->lr_sid);
1693 		if (status)
1694 			return status;
1695 
1696 		READ_BUF(4);
1697 		lrp->lrf_body_len = be32_to_cpup(p++);
1698 		if (lrp->lrf_body_len > 0) {
1699 			READ_BUF(lrp->lrf_body_len);
1700 			READMEM(lrp->lrf_body, lrp->lrf_body_len);
1701 		}
1702 	} else {
1703 		lrp->lr_seg.offset = 0;
1704 		lrp->lr_seg.length = NFS4_MAX_UINT64;
1705 	}
1706 
1707 	DECODE_TAIL;
1708 }
1709 #endif /* CONFIG_NFSD_PNFS */
1710 
1711 static __be32
1712 nfsd4_decode_fallocate(struct nfsd4_compoundargs *argp,
1713 		       struct nfsd4_fallocate *fallocate)
1714 {
1715 	DECODE_HEAD;
1716 
1717 	status = nfsd4_decode_stateid(argp, &fallocate->falloc_stateid);
1718 	if (status)
1719 		return status;
1720 
1721 	READ_BUF(16);
1722 	p = xdr_decode_hyper(p, &fallocate->falloc_offset);
1723 	xdr_decode_hyper(p, &fallocate->falloc_length);
1724 
1725 	DECODE_TAIL;
1726 }
1727 
1728 static __be32
1729 nfsd4_decode_clone(struct nfsd4_compoundargs *argp, struct nfsd4_clone *clone)
1730 {
1731 	DECODE_HEAD;
1732 
1733 	status = nfsd4_decode_stateid(argp, &clone->cl_src_stateid);
1734 	if (status)
1735 		return status;
1736 	status = nfsd4_decode_stateid(argp, &clone->cl_dst_stateid);
1737 	if (status)
1738 		return status;
1739 
1740 	READ_BUF(8 + 8 + 8);
1741 	p = xdr_decode_hyper(p, &clone->cl_src_pos);
1742 	p = xdr_decode_hyper(p, &clone->cl_dst_pos);
1743 	p = xdr_decode_hyper(p, &clone->cl_count);
1744 	DECODE_TAIL;
1745 }
1746 
1747 static __be32
1748 nfsd4_decode_copy(struct nfsd4_compoundargs *argp, struct nfsd4_copy *copy)
1749 {
1750 	DECODE_HEAD;
1751 	unsigned int tmp;
1752 
1753 	status = nfsd4_decode_stateid(argp, &copy->cp_src_stateid);
1754 	if (status)
1755 		return status;
1756 	status = nfsd4_decode_stateid(argp, &copy->cp_dst_stateid);
1757 	if (status)
1758 		return status;
1759 
1760 	READ_BUF(8 + 8 + 8 + 4 + 4 + 4);
1761 	p = xdr_decode_hyper(p, &copy->cp_src_pos);
1762 	p = xdr_decode_hyper(p, &copy->cp_dst_pos);
1763 	p = xdr_decode_hyper(p, &copy->cp_count);
1764 	p++; /* ca_consecutive: we always do consecutive copies */
1765 	copy->cp_synchronous = be32_to_cpup(p++);
1766 	tmp = be32_to_cpup(p); /* Source server list not supported */
1767 
1768 	DECODE_TAIL;
1769 }
1770 
1771 static __be32
1772 nfsd4_decode_offload_status(struct nfsd4_compoundargs *argp,
1773 			    struct nfsd4_offload_status *os)
1774 {
1775 	return nfsd4_decode_stateid(argp, &os->stateid);
1776 }
1777 
1778 static __be32
1779 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
1780 {
1781 	DECODE_HEAD;
1782 
1783 	status = nfsd4_decode_stateid(argp, &seek->seek_stateid);
1784 	if (status)
1785 		return status;
1786 
1787 	READ_BUF(8 + 4);
1788 	p = xdr_decode_hyper(p, &seek->seek_offset);
1789 	seek->seek_whence = be32_to_cpup(p);
1790 
1791 	DECODE_TAIL;
1792 }
1793 
1794 static __be32
1795 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1796 {
1797 	return nfs_ok;
1798 }
1799 
1800 static __be32
1801 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1802 {
1803 	return nfserr_notsupp;
1804 }
1805 
1806 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1807 
1808 static const nfsd4_dec nfsd4_dec_ops[] = {
1809 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1810 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1811 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1812 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1813 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1814 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1815 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1816 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1817 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1818 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1819 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1820 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1821 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1822 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1823 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1824 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1825 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1826 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1827 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1828 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1829 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_putpubfh,
1830 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1831 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1832 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1833 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1834 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1835 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1836 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1837 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1838 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1839 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1840 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1841 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1842 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1843 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1844 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1845 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1846 
1847 	/* new operations for NFSv4.1 */
1848 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_backchannel_ctl,
1849 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1850 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1851 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1852 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1853 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
1854 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1855 #ifdef CONFIG_NFSD_PNFS
1856 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_getdeviceinfo,
1857 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1858 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_layoutcommit,
1859 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_layoutget,
1860 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_layoutreturn,
1861 #else
1862 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1863 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1864 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1865 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1866 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1867 #endif
1868 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1869 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1870 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1871 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
1872 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1873 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
1874 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1875 
1876 	/* new operations for NFSv4.2 */
1877 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1878 	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_copy,
1879 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
1880 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1881 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1882 	[OP_LAYOUTERROR]	= (nfsd4_dec)nfsd4_decode_notsupp,
1883 	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1884 	[OP_OFFLOAD_CANCEL]	= (nfsd4_dec)nfsd4_decode_offload_status,
1885 	[OP_OFFLOAD_STATUS]	= (nfsd4_dec)nfsd4_decode_offload_status,
1886 	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_notsupp,
1887 	[OP_SEEK]		= (nfsd4_dec)nfsd4_decode_seek,
1888 	[OP_WRITE_SAME]		= (nfsd4_dec)nfsd4_decode_notsupp,
1889 	[OP_CLONE]		= (nfsd4_dec)nfsd4_decode_clone,
1890 };
1891 
1892 static inline bool
1893 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
1894 {
1895 	if (op->opnum < FIRST_NFS4_OP)
1896 		return false;
1897 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
1898 		return false;
1899 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
1900 		return false;
1901 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
1902 		return false;
1903 	return true;
1904 }
1905 
1906 static __be32
1907 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1908 {
1909 	DECODE_HEAD;
1910 	struct nfsd4_op *op;
1911 	bool cachethis = false;
1912 	int auth_slack= argp->rqstp->rq_auth_slack;
1913 	int max_reply = auth_slack + 8; /* opcnt, status */
1914 	int readcount = 0;
1915 	int readbytes = 0;
1916 	int i;
1917 
1918 	READ_BUF(4);
1919 	argp->taglen = be32_to_cpup(p++);
1920 	READ_BUF(argp->taglen);
1921 	SAVEMEM(argp->tag, argp->taglen);
1922 	READ_BUF(8);
1923 	argp->minorversion = be32_to_cpup(p++);
1924 	argp->opcnt = be32_to_cpup(p++);
1925 	max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
1926 
1927 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1928 		goto xdr_error;
1929 	/*
1930 	 * NFS4ERR_RESOURCE is a more helpful error than GARBAGE_ARGS
1931 	 * here, so we return success at the xdr level so that
1932 	 * nfsd4_proc can handle this is an NFS-level error.
1933 	 */
1934 	if (argp->opcnt > NFSD_MAX_OPS_PER_COMPOUND)
1935 		return 0;
1936 
1937 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1938 		argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1939 		if (!argp->ops) {
1940 			argp->ops = argp->iops;
1941 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1942 			goto xdr_error;
1943 		}
1944 	}
1945 
1946 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
1947 		argp->opcnt = 0;
1948 
1949 	for (i = 0; i < argp->opcnt; i++) {
1950 		op = &argp->ops[i];
1951 		op->replay = NULL;
1952 
1953 		READ_BUF(4);
1954 		op->opnum = be32_to_cpup(p++);
1955 
1956 		if (nfsd4_opnum_in_range(argp, op))
1957 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
1958 		else {
1959 			op->opnum = OP_ILLEGAL;
1960 			op->status = nfserr_op_illegal;
1961 		}
1962 		op->opdesc = OPDESC(op);
1963 		/*
1964 		 * We'll try to cache the result in the DRC if any one
1965 		 * op in the compound wants to be cached:
1966 		 */
1967 		cachethis |= nfsd4_cache_this_op(op);
1968 
1969 		if (op->opnum == OP_READ) {
1970 			readcount++;
1971 			readbytes += nfsd4_max_reply(argp->rqstp, op);
1972 		} else
1973 			max_reply += nfsd4_max_reply(argp->rqstp, op);
1974 		/*
1975 		 * OP_LOCK and OP_LOCKT may return a conflicting lock.
1976 		 * (Special case because it will just skip encoding this
1977 		 * if it runs out of xdr buffer space, and it is the only
1978 		 * operation that behaves this way.)
1979 		 */
1980 		if (op->opnum == OP_LOCK || op->opnum == OP_LOCKT)
1981 			max_reply += NFS4_OPAQUE_LIMIT;
1982 
1983 		if (op->status) {
1984 			argp->opcnt = i+1;
1985 			break;
1986 		}
1987 	}
1988 	/* Sessions make the DRC unnecessary: */
1989 	if (argp->minorversion)
1990 		cachethis = false;
1991 	svc_reserve(argp->rqstp, max_reply + readbytes);
1992 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1993 
1994 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
1995 		clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
1996 
1997 	DECODE_TAIL;
1998 }
1999 
2000 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode,
2001 			     struct svc_export *exp)
2002 {
2003 	if (exp->ex_flags & NFSEXP_V4ROOT) {
2004 		*p++ = cpu_to_be32(convert_to_wallclock(exp->cd->flush_time));
2005 		*p++ = 0;
2006 	} else if (IS_I_VERSION(inode)) {
2007 		p = xdr_encode_hyper(p, nfsd4_change_attribute(stat, inode));
2008 	} else {
2009 		*p++ = cpu_to_be32(stat->ctime.tv_sec);
2010 		*p++ = cpu_to_be32(stat->ctime.tv_nsec);
2011 	}
2012 	return p;
2013 }
2014 
2015 /*
2016  * ctime (in NFSv4, time_metadata) is not writeable, and the client
2017  * doesn't really care what resolution could theoretically be stored by
2018  * the filesystem.
2019  *
2020  * The client cares how close together changes can be while still
2021  * guaranteeing ctime changes.  For most filesystems (which have
2022  * timestamps with nanosecond fields) that is limited by the resolution
2023  * of the time returned from current_time() (which I'm assuming to be
2024  * 1/HZ).
2025  */
2026 static __be32 *encode_time_delta(__be32 *p, struct inode *inode)
2027 {
2028 	struct timespec ts;
2029 	u32 ns;
2030 
2031 	ns = max_t(u32, NSEC_PER_SEC/HZ, inode->i_sb->s_time_gran);
2032 	ts = ns_to_timespec(ns);
2033 
2034 	p = xdr_encode_hyper(p, ts.tv_sec);
2035 	*p++ = cpu_to_be32(ts.tv_nsec);
2036 
2037 	return p;
2038 }
2039 
2040 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
2041 {
2042 	*p++ = cpu_to_be32(c->atomic);
2043 	if (c->change_supported) {
2044 		p = xdr_encode_hyper(p, c->before_change);
2045 		p = xdr_encode_hyper(p, c->after_change);
2046 	} else {
2047 		*p++ = cpu_to_be32(c->before_ctime_sec);
2048 		*p++ = cpu_to_be32(c->before_ctime_nsec);
2049 		*p++ = cpu_to_be32(c->after_ctime_sec);
2050 		*p++ = cpu_to_be32(c->after_ctime_nsec);
2051 	}
2052 	return p;
2053 }
2054 
2055 /* Encode as an array of strings the string given with components
2056  * separated @sep, escaped with esc_enter and esc_exit.
2057  */
2058 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
2059 					  char *components, char esc_enter,
2060 					  char esc_exit)
2061 {
2062 	__be32 *p;
2063 	__be32 pathlen;
2064 	int pathlen_offset;
2065 	int strlen, count=0;
2066 	char *str, *end, *next;
2067 
2068 	dprintk("nfsd4_encode_components(%s)\n", components);
2069 
2070 	pathlen_offset = xdr->buf->len;
2071 	p = xdr_reserve_space(xdr, 4);
2072 	if (!p)
2073 		return nfserr_resource;
2074 	p++; /* We will fill this in with @count later */
2075 
2076 	end = str = components;
2077 	while (*end) {
2078 		bool found_esc = false;
2079 
2080 		/* try to parse as esc_start, ..., esc_end, sep */
2081 		if (*str == esc_enter) {
2082 			for (; *end && (*end != esc_exit); end++)
2083 				/* find esc_exit or end of string */;
2084 			next = end + 1;
2085 			if (*end && (!*next || *next == sep)) {
2086 				str++;
2087 				found_esc = true;
2088 			}
2089 		}
2090 
2091 		if (!found_esc)
2092 			for (; *end && (*end != sep); end++)
2093 				/* find sep or end of string */;
2094 
2095 		strlen = end - str;
2096 		if (strlen) {
2097 			p = xdr_reserve_space(xdr, strlen + 4);
2098 			if (!p)
2099 				return nfserr_resource;
2100 			p = xdr_encode_opaque(p, str, strlen);
2101 			count++;
2102 		}
2103 		else
2104 			end++;
2105 		if (found_esc)
2106 			end = next;
2107 
2108 		str = end;
2109 	}
2110 	pathlen = htonl(count);
2111 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
2112 	return 0;
2113 }
2114 
2115 /* Encode as an array of strings the string given with components
2116  * separated @sep.
2117  */
2118 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
2119 				      char *components)
2120 {
2121 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
2122 }
2123 
2124 /*
2125  * encode a location element of a fs_locations structure
2126  */
2127 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
2128 					struct nfsd4_fs_location *location)
2129 {
2130 	__be32 status;
2131 
2132 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
2133 						'[', ']');
2134 	if (status)
2135 		return status;
2136 	status = nfsd4_encode_components(xdr, '/', location->path);
2137 	if (status)
2138 		return status;
2139 	return 0;
2140 }
2141 
2142 /*
2143  * Encode a path in RFC3530 'pathname4' format
2144  */
2145 static __be32 nfsd4_encode_path(struct xdr_stream *xdr,
2146 				const struct path *root,
2147 				const struct path *path)
2148 {
2149 	struct path cur = *path;
2150 	__be32 *p;
2151 	struct dentry **components = NULL;
2152 	unsigned int ncomponents = 0;
2153 	__be32 err = nfserr_jukebox;
2154 
2155 	dprintk("nfsd4_encode_components(");
2156 
2157 	path_get(&cur);
2158 	/* First walk the path up to the nfsd root, and store the
2159 	 * dentries/path components in an array.
2160 	 */
2161 	for (;;) {
2162 		if (path_equal(&cur, root))
2163 			break;
2164 		if (cur.dentry == cur.mnt->mnt_root) {
2165 			if (follow_up(&cur))
2166 				continue;
2167 			goto out_free;
2168 		}
2169 		if ((ncomponents & 15) == 0) {
2170 			struct dentry **new;
2171 			new = krealloc(components,
2172 					sizeof(*new) * (ncomponents + 16),
2173 					GFP_KERNEL);
2174 			if (!new)
2175 				goto out_free;
2176 			components = new;
2177 		}
2178 		components[ncomponents++] = cur.dentry;
2179 		cur.dentry = dget_parent(cur.dentry);
2180 	}
2181 	err = nfserr_resource;
2182 	p = xdr_reserve_space(xdr, 4);
2183 	if (!p)
2184 		goto out_free;
2185 	*p++ = cpu_to_be32(ncomponents);
2186 
2187 	while (ncomponents) {
2188 		struct dentry *dentry = components[ncomponents - 1];
2189 		unsigned int len;
2190 
2191 		spin_lock(&dentry->d_lock);
2192 		len = dentry->d_name.len;
2193 		p = xdr_reserve_space(xdr, len + 4);
2194 		if (!p) {
2195 			spin_unlock(&dentry->d_lock);
2196 			goto out_free;
2197 		}
2198 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
2199 		dprintk("/%pd", dentry);
2200 		spin_unlock(&dentry->d_lock);
2201 		dput(dentry);
2202 		ncomponents--;
2203 	}
2204 
2205 	err = 0;
2206 out_free:
2207 	dprintk(")\n");
2208 	while (ncomponents)
2209 		dput(components[--ncomponents]);
2210 	kfree(components);
2211 	path_put(&cur);
2212 	return err;
2213 }
2214 
2215 static __be32 nfsd4_encode_fsloc_fsroot(struct xdr_stream *xdr,
2216 			struct svc_rqst *rqstp, const struct path *path)
2217 {
2218 	struct svc_export *exp_ps;
2219 	__be32 res;
2220 
2221 	exp_ps = rqst_find_fsidzero_export(rqstp);
2222 	if (IS_ERR(exp_ps))
2223 		return nfserrno(PTR_ERR(exp_ps));
2224 	res = nfsd4_encode_path(xdr, &exp_ps->ex_path, path);
2225 	exp_put(exp_ps);
2226 	return res;
2227 }
2228 
2229 /*
2230  *  encode a fs_locations structure
2231  */
2232 static __be32 nfsd4_encode_fs_locations(struct xdr_stream *xdr,
2233 			struct svc_rqst *rqstp, struct svc_export *exp)
2234 {
2235 	__be32 status;
2236 	int i;
2237 	__be32 *p;
2238 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
2239 
2240 	status = nfsd4_encode_fsloc_fsroot(xdr, rqstp, &exp->ex_path);
2241 	if (status)
2242 		return status;
2243 	p = xdr_reserve_space(xdr, 4);
2244 	if (!p)
2245 		return nfserr_resource;
2246 	*p++ = cpu_to_be32(fslocs->locations_count);
2247 	for (i=0; i<fslocs->locations_count; i++) {
2248 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
2249 		if (status)
2250 			return status;
2251 	}
2252 	return 0;
2253 }
2254 
2255 static u32 nfs4_file_type(umode_t mode)
2256 {
2257 	switch (mode & S_IFMT) {
2258 	case S_IFIFO:	return NF4FIFO;
2259 	case S_IFCHR:	return NF4CHR;
2260 	case S_IFDIR:	return NF4DIR;
2261 	case S_IFBLK:	return NF4BLK;
2262 	case S_IFLNK:	return NF4LNK;
2263 	case S_IFREG:	return NF4REG;
2264 	case S_IFSOCK:	return NF4SOCK;
2265 	default:	return NF4BAD;
2266 	};
2267 }
2268 
2269 static inline __be32
2270 nfsd4_encode_aclname(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2271 		     struct nfs4_ace *ace)
2272 {
2273 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
2274 		return nfs4_acl_write_who(xdr, ace->whotype);
2275 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
2276 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
2277 	else
2278 		return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
2279 }
2280 
2281 static inline __be32
2282 nfsd4_encode_layout_types(struct xdr_stream *xdr, u32 layout_types)
2283 {
2284 	__be32		*p;
2285 	unsigned long	i = hweight_long(layout_types);
2286 
2287 	p = xdr_reserve_space(xdr, 4 + 4 * i);
2288 	if (!p)
2289 		return nfserr_resource;
2290 
2291 	*p++ = cpu_to_be32(i);
2292 
2293 	for (i = LAYOUT_NFSV4_1_FILES; i < LAYOUT_TYPE_MAX; ++i)
2294 		if (layout_types & (1 << i))
2295 			*p++ = cpu_to_be32(i);
2296 
2297 	return 0;
2298 }
2299 
2300 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
2301 			      FATTR4_WORD0_RDATTR_ERROR)
2302 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2303 #define WORD2_ABSENT_FS_ATTRS 0
2304 
2305 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2306 static inline __be32
2307 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2308 			    void *context, int len)
2309 {
2310 	__be32 *p;
2311 
2312 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2313 	if (!p)
2314 		return nfserr_resource;
2315 
2316 	/*
2317 	 * For now we use a 0 here to indicate the null translation; in
2318 	 * the future we may place a call to translation code here.
2319 	 */
2320 	*p++ = cpu_to_be32(0); /* lfs */
2321 	*p++ = cpu_to_be32(0); /* pi */
2322 	p = xdr_encode_opaque(p, context, len);
2323 	return 0;
2324 }
2325 #else
2326 static inline __be32
2327 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2328 			    void *context, int len)
2329 { return 0; }
2330 #endif
2331 
2332 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *bmval2, u32 *rdattr_err)
2333 {
2334 	/* As per referral draft:  */
2335 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2336 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2337 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2338 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2339 			*rdattr_err = NFSERR_MOVED;
2340 		else
2341 			return nfserr_moved;
2342 	}
2343 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2344 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2345 	*bmval2 &= WORD2_ABSENT_FS_ATTRS;
2346 	return 0;
2347 }
2348 
2349 
2350 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2351 {
2352 	struct path path = exp->ex_path;
2353 	int err;
2354 
2355 	path_get(&path);
2356 	while (follow_up(&path)) {
2357 		if (path.dentry != path.mnt->mnt_root)
2358 			break;
2359 	}
2360 	err = vfs_getattr(&path, stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
2361 	path_put(&path);
2362 	return err;
2363 }
2364 
2365 static __be32
2366 nfsd4_encode_bitmap(struct xdr_stream *xdr, u32 bmval0, u32 bmval1, u32 bmval2)
2367 {
2368 	__be32 *p;
2369 
2370 	if (bmval2) {
2371 		p = xdr_reserve_space(xdr, 16);
2372 		if (!p)
2373 			goto out_resource;
2374 		*p++ = cpu_to_be32(3);
2375 		*p++ = cpu_to_be32(bmval0);
2376 		*p++ = cpu_to_be32(bmval1);
2377 		*p++ = cpu_to_be32(bmval2);
2378 	} else if (bmval1) {
2379 		p = xdr_reserve_space(xdr, 12);
2380 		if (!p)
2381 			goto out_resource;
2382 		*p++ = cpu_to_be32(2);
2383 		*p++ = cpu_to_be32(bmval0);
2384 		*p++ = cpu_to_be32(bmval1);
2385 	} else {
2386 		p = xdr_reserve_space(xdr, 8);
2387 		if (!p)
2388 			goto out_resource;
2389 		*p++ = cpu_to_be32(1);
2390 		*p++ = cpu_to_be32(bmval0);
2391 	}
2392 
2393 	return 0;
2394 out_resource:
2395 	return nfserr_resource;
2396 }
2397 
2398 /*
2399  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2400  * ourselves.
2401  */
2402 static __be32
2403 nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
2404 		struct svc_export *exp,
2405 		struct dentry *dentry, u32 *bmval,
2406 		struct svc_rqst *rqstp, int ignore_crossmnt)
2407 {
2408 	u32 bmval0 = bmval[0];
2409 	u32 bmval1 = bmval[1];
2410 	u32 bmval2 = bmval[2];
2411 	struct kstat stat;
2412 	struct svc_fh *tempfh = NULL;
2413 	struct kstatfs statfs;
2414 	__be32 *p;
2415 	int starting_len = xdr->buf->len;
2416 	int attrlen_offset;
2417 	__be32 attrlen;
2418 	u32 dummy;
2419 	u64 dummy64;
2420 	u32 rdattr_err = 0;
2421 	__be32 status;
2422 	int err;
2423 	struct nfs4_acl *acl = NULL;
2424 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2425 	void *context = NULL;
2426 	int contextlen;
2427 #endif
2428 	bool contextsupport = false;
2429 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2430 	u32 minorversion = resp->cstate.minorversion;
2431 	struct path path = {
2432 		.mnt	= exp->ex_path.mnt,
2433 		.dentry	= dentry,
2434 	};
2435 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2436 
2437 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2438 	BUG_ON(!nfsd_attrs_supported(minorversion, bmval));
2439 
2440 	if (exp->ex_fslocs.migrated) {
2441 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &bmval2, &rdattr_err);
2442 		if (status)
2443 			goto out;
2444 	}
2445 
2446 	err = vfs_getattr(&path, &stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
2447 	if (err)
2448 		goto out_nfserr;
2449 	if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
2450 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
2451 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2452 		       FATTR4_WORD1_SPACE_TOTAL))) {
2453 		err = vfs_statfs(&path, &statfs);
2454 		if (err)
2455 			goto out_nfserr;
2456 	}
2457 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2458 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2459 		status = nfserr_jukebox;
2460 		if (!tempfh)
2461 			goto out;
2462 		fh_init(tempfh, NFS4_FHSIZE);
2463 		status = fh_compose(tempfh, exp, dentry, NULL);
2464 		if (status)
2465 			goto out;
2466 		fhp = tempfh;
2467 	}
2468 	if (bmval0 & FATTR4_WORD0_ACL) {
2469 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2470 		if (err == -EOPNOTSUPP)
2471 			bmval0 &= ~FATTR4_WORD0_ACL;
2472 		else if (err == -EINVAL) {
2473 			status = nfserr_attrnotsupp;
2474 			goto out;
2475 		} else if (err != 0)
2476 			goto out_nfserr;
2477 	}
2478 
2479 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2480 	if ((bmval2 & FATTR4_WORD2_SECURITY_LABEL) ||
2481 	     bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2482 		if (exp->ex_flags & NFSEXP_SECURITY_LABEL)
2483 			err = security_inode_getsecctx(d_inode(dentry),
2484 						&context, &contextlen);
2485 		else
2486 			err = -EOPNOTSUPP;
2487 		contextsupport = (err == 0);
2488 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2489 			if (err == -EOPNOTSUPP)
2490 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2491 			else if (err)
2492 				goto out_nfserr;
2493 		}
2494 	}
2495 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2496 
2497 	status = nfsd4_encode_bitmap(xdr, bmval0, bmval1, bmval2);
2498 	if (status)
2499 		goto out;
2500 
2501 	attrlen_offset = xdr->buf->len;
2502 	p = xdr_reserve_space(xdr, 4);
2503 	if (!p)
2504 		goto out_resource;
2505 	p++;                /* to be backfilled later */
2506 
2507 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2508 		u32 supp[3];
2509 
2510 		memcpy(supp, nfsd_suppattrs[minorversion], sizeof(supp));
2511 
2512 		if (!IS_POSIXACL(dentry->d_inode))
2513 			supp[0] &= ~FATTR4_WORD0_ACL;
2514 		if (!contextsupport)
2515 			supp[2] &= ~FATTR4_WORD2_SECURITY_LABEL;
2516 		if (!supp[2]) {
2517 			p = xdr_reserve_space(xdr, 12);
2518 			if (!p)
2519 				goto out_resource;
2520 			*p++ = cpu_to_be32(2);
2521 			*p++ = cpu_to_be32(supp[0]);
2522 			*p++ = cpu_to_be32(supp[1]);
2523 		} else {
2524 			p = xdr_reserve_space(xdr, 16);
2525 			if (!p)
2526 				goto out_resource;
2527 			*p++ = cpu_to_be32(3);
2528 			*p++ = cpu_to_be32(supp[0]);
2529 			*p++ = cpu_to_be32(supp[1]);
2530 			*p++ = cpu_to_be32(supp[2]);
2531 		}
2532 	}
2533 	if (bmval0 & FATTR4_WORD0_TYPE) {
2534 		p = xdr_reserve_space(xdr, 4);
2535 		if (!p)
2536 			goto out_resource;
2537 		dummy = nfs4_file_type(stat.mode);
2538 		if (dummy == NF4BAD) {
2539 			status = nfserr_serverfault;
2540 			goto out;
2541 		}
2542 		*p++ = cpu_to_be32(dummy);
2543 	}
2544 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2545 		p = xdr_reserve_space(xdr, 4);
2546 		if (!p)
2547 			goto out_resource;
2548 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2549 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT);
2550 		else
2551 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT|
2552 						NFS4_FH_VOL_RENAME);
2553 	}
2554 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2555 		p = xdr_reserve_space(xdr, 8);
2556 		if (!p)
2557 			goto out_resource;
2558 		p = encode_change(p, &stat, d_inode(dentry), exp);
2559 	}
2560 	if (bmval0 & FATTR4_WORD0_SIZE) {
2561 		p = xdr_reserve_space(xdr, 8);
2562 		if (!p)
2563 			goto out_resource;
2564 		p = xdr_encode_hyper(p, stat.size);
2565 	}
2566 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2567 		p = xdr_reserve_space(xdr, 4);
2568 		if (!p)
2569 			goto out_resource;
2570 		*p++ = cpu_to_be32(1);
2571 	}
2572 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2573 		p = xdr_reserve_space(xdr, 4);
2574 		if (!p)
2575 			goto out_resource;
2576 		*p++ = cpu_to_be32(1);
2577 	}
2578 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2579 		p = xdr_reserve_space(xdr, 4);
2580 		if (!p)
2581 			goto out_resource;
2582 		*p++ = cpu_to_be32(0);
2583 	}
2584 	if (bmval0 & FATTR4_WORD0_FSID) {
2585 		p = xdr_reserve_space(xdr, 16);
2586 		if (!p)
2587 			goto out_resource;
2588 		if (exp->ex_fslocs.migrated) {
2589 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
2590 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
2591 		} else switch(fsid_source(fhp)) {
2592 		case FSIDSOURCE_FSID:
2593 			p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
2594 			p = xdr_encode_hyper(p, (u64)0);
2595 			break;
2596 		case FSIDSOURCE_DEV:
2597 			*p++ = cpu_to_be32(0);
2598 			*p++ = cpu_to_be32(MAJOR(stat.dev));
2599 			*p++ = cpu_to_be32(0);
2600 			*p++ = cpu_to_be32(MINOR(stat.dev));
2601 			break;
2602 		case FSIDSOURCE_UUID:
2603 			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
2604 								EX_UUID_LEN);
2605 			break;
2606 		}
2607 	}
2608 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2609 		p = xdr_reserve_space(xdr, 4);
2610 		if (!p)
2611 			goto out_resource;
2612 		*p++ = cpu_to_be32(0);
2613 	}
2614 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2615 		p = xdr_reserve_space(xdr, 4);
2616 		if (!p)
2617 			goto out_resource;
2618 		*p++ = cpu_to_be32(nn->nfsd4_lease);
2619 	}
2620 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2621 		p = xdr_reserve_space(xdr, 4);
2622 		if (!p)
2623 			goto out_resource;
2624 		*p++ = cpu_to_be32(rdattr_err);
2625 	}
2626 	if (bmval0 & FATTR4_WORD0_ACL) {
2627 		struct nfs4_ace *ace;
2628 
2629 		if (acl == NULL) {
2630 			p = xdr_reserve_space(xdr, 4);
2631 			if (!p)
2632 				goto out_resource;
2633 
2634 			*p++ = cpu_to_be32(0);
2635 			goto out_acl;
2636 		}
2637 		p = xdr_reserve_space(xdr, 4);
2638 		if (!p)
2639 			goto out_resource;
2640 		*p++ = cpu_to_be32(acl->naces);
2641 
2642 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2643 			p = xdr_reserve_space(xdr, 4*3);
2644 			if (!p)
2645 				goto out_resource;
2646 			*p++ = cpu_to_be32(ace->type);
2647 			*p++ = cpu_to_be32(ace->flag);
2648 			*p++ = cpu_to_be32(ace->access_mask &
2649 							NFS4_ACE_MASK_ALL);
2650 			status = nfsd4_encode_aclname(xdr, rqstp, ace);
2651 			if (status)
2652 				goto out;
2653 		}
2654 	}
2655 out_acl:
2656 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2657 		p = xdr_reserve_space(xdr, 4);
2658 		if (!p)
2659 			goto out_resource;
2660 		*p++ = cpu_to_be32(IS_POSIXACL(dentry->d_inode) ?
2661 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2662 	}
2663 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2664 		p = xdr_reserve_space(xdr, 4);
2665 		if (!p)
2666 			goto out_resource;
2667 		*p++ = cpu_to_be32(1);
2668 	}
2669 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2670 		p = xdr_reserve_space(xdr, 4);
2671 		if (!p)
2672 			goto out_resource;
2673 		*p++ = cpu_to_be32(0);
2674 	}
2675 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2676 		p = xdr_reserve_space(xdr, 4);
2677 		if (!p)
2678 			goto out_resource;
2679 		*p++ = cpu_to_be32(1);
2680 	}
2681 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2682 		p = xdr_reserve_space(xdr, 4);
2683 		if (!p)
2684 			goto out_resource;
2685 		*p++ = cpu_to_be32(1);
2686 	}
2687 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2688 		p = xdr_reserve_space(xdr, fhp->fh_handle.fh_size + 4);
2689 		if (!p)
2690 			goto out_resource;
2691 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base,
2692 					fhp->fh_handle.fh_size);
2693 	}
2694 	if (bmval0 & FATTR4_WORD0_FILEID) {
2695 		p = xdr_reserve_space(xdr, 8);
2696 		if (!p)
2697 			goto out_resource;
2698 		p = xdr_encode_hyper(p, stat.ino);
2699 	}
2700 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2701 		p = xdr_reserve_space(xdr, 8);
2702 		if (!p)
2703 			goto out_resource;
2704 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2705 	}
2706 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2707 		p = xdr_reserve_space(xdr, 8);
2708 		if (!p)
2709 			goto out_resource;
2710 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2711 	}
2712 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2713 		p = xdr_reserve_space(xdr, 8);
2714 		if (!p)
2715 			goto out_resource;
2716 		p = xdr_encode_hyper(p, (u64) statfs.f_files);
2717 	}
2718 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2719 		status = nfsd4_encode_fs_locations(xdr, rqstp, exp);
2720 		if (status)
2721 			goto out;
2722 	}
2723 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2724 		p = xdr_reserve_space(xdr, 4);
2725 		if (!p)
2726 			goto out_resource;
2727 		*p++ = cpu_to_be32(1);
2728 	}
2729 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2730 		p = xdr_reserve_space(xdr, 8);
2731 		if (!p)
2732 			goto out_resource;
2733 		p = xdr_encode_hyper(p, exp->ex_path.mnt->mnt_sb->s_maxbytes);
2734 	}
2735 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2736 		p = xdr_reserve_space(xdr, 4);
2737 		if (!p)
2738 			goto out_resource;
2739 		*p++ = cpu_to_be32(255);
2740 	}
2741 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2742 		p = xdr_reserve_space(xdr, 4);
2743 		if (!p)
2744 			goto out_resource;
2745 		*p++ = cpu_to_be32(statfs.f_namelen);
2746 	}
2747 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2748 		p = xdr_reserve_space(xdr, 8);
2749 		if (!p)
2750 			goto out_resource;
2751 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2752 	}
2753 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2754 		p = xdr_reserve_space(xdr, 8);
2755 		if (!p)
2756 			goto out_resource;
2757 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2758 	}
2759 	if (bmval1 & FATTR4_WORD1_MODE) {
2760 		p = xdr_reserve_space(xdr, 4);
2761 		if (!p)
2762 			goto out_resource;
2763 		*p++ = cpu_to_be32(stat.mode & S_IALLUGO);
2764 	}
2765 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2766 		p = xdr_reserve_space(xdr, 4);
2767 		if (!p)
2768 			goto out_resource;
2769 		*p++ = cpu_to_be32(1);
2770 	}
2771 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2772 		p = xdr_reserve_space(xdr, 4);
2773 		if (!p)
2774 			goto out_resource;
2775 		*p++ = cpu_to_be32(stat.nlink);
2776 	}
2777 	if (bmval1 & FATTR4_WORD1_OWNER) {
2778 		status = nfsd4_encode_user(xdr, rqstp, stat.uid);
2779 		if (status)
2780 			goto out;
2781 	}
2782 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2783 		status = nfsd4_encode_group(xdr, rqstp, stat.gid);
2784 		if (status)
2785 			goto out;
2786 	}
2787 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2788 		p = xdr_reserve_space(xdr, 8);
2789 		if (!p)
2790 			goto out_resource;
2791 		*p++ = cpu_to_be32((u32) MAJOR(stat.rdev));
2792 		*p++ = cpu_to_be32((u32) MINOR(stat.rdev));
2793 	}
2794 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2795 		p = xdr_reserve_space(xdr, 8);
2796 		if (!p)
2797 			goto out_resource;
2798 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2799 		p = xdr_encode_hyper(p, dummy64);
2800 	}
2801 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2802 		p = xdr_reserve_space(xdr, 8);
2803 		if (!p)
2804 			goto out_resource;
2805 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2806 		p = xdr_encode_hyper(p, dummy64);
2807 	}
2808 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2809 		p = xdr_reserve_space(xdr, 8);
2810 		if (!p)
2811 			goto out_resource;
2812 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2813 		p = xdr_encode_hyper(p, dummy64);
2814 	}
2815 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2816 		p = xdr_reserve_space(xdr, 8);
2817 		if (!p)
2818 			goto out_resource;
2819 		dummy64 = (u64)stat.blocks << 9;
2820 		p = xdr_encode_hyper(p, dummy64);
2821 	}
2822 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2823 		p = xdr_reserve_space(xdr, 12);
2824 		if (!p)
2825 			goto out_resource;
2826 		p = xdr_encode_hyper(p, (s64)stat.atime.tv_sec);
2827 		*p++ = cpu_to_be32(stat.atime.tv_nsec);
2828 	}
2829 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2830 		p = xdr_reserve_space(xdr, 12);
2831 		if (!p)
2832 			goto out_resource;
2833 		p = encode_time_delta(p, d_inode(dentry));
2834 	}
2835 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2836 		p = xdr_reserve_space(xdr, 12);
2837 		if (!p)
2838 			goto out_resource;
2839 		p = xdr_encode_hyper(p, (s64)stat.ctime.tv_sec);
2840 		*p++ = cpu_to_be32(stat.ctime.tv_nsec);
2841 	}
2842 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2843 		p = xdr_reserve_space(xdr, 12);
2844 		if (!p)
2845 			goto out_resource;
2846 		p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
2847 		*p++ = cpu_to_be32(stat.mtime.tv_nsec);
2848 	}
2849 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2850 		struct kstat parent_stat;
2851 		u64 ino = stat.ino;
2852 
2853 		p = xdr_reserve_space(xdr, 8);
2854 		if (!p)
2855                 	goto out_resource;
2856 		/*
2857 		 * Get parent's attributes if not ignoring crossmount
2858 		 * and this is the root of a cross-mounted filesystem.
2859 		 */
2860 		if (ignore_crossmnt == 0 &&
2861 		    dentry == exp->ex_path.mnt->mnt_root) {
2862 			err = get_parent_attributes(exp, &parent_stat);
2863 			if (err)
2864 				goto out_nfserr;
2865 			ino = parent_stat.ino;
2866 		}
2867 		p = xdr_encode_hyper(p, ino);
2868 	}
2869 #ifdef CONFIG_NFSD_PNFS
2870 	if (bmval1 & FATTR4_WORD1_FS_LAYOUT_TYPES) {
2871 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
2872 		if (status)
2873 			goto out;
2874 	}
2875 
2876 	if (bmval2 & FATTR4_WORD2_LAYOUT_TYPES) {
2877 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
2878 		if (status)
2879 			goto out;
2880 	}
2881 
2882 	if (bmval2 & FATTR4_WORD2_LAYOUT_BLKSIZE) {
2883 		p = xdr_reserve_space(xdr, 4);
2884 		if (!p)
2885 			goto out_resource;
2886 		*p++ = cpu_to_be32(stat.blksize);
2887 	}
2888 #endif /* CONFIG_NFSD_PNFS */
2889 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2890 		u32 supp[3];
2891 
2892 		memcpy(supp, nfsd_suppattrs[minorversion], sizeof(supp));
2893 		supp[0] &= NFSD_SUPPATTR_EXCLCREAT_WORD0;
2894 		supp[1] &= NFSD_SUPPATTR_EXCLCREAT_WORD1;
2895 		supp[2] &= NFSD_SUPPATTR_EXCLCREAT_WORD2;
2896 
2897 		status = nfsd4_encode_bitmap(xdr, supp[0], supp[1], supp[2]);
2898 		if (status)
2899 			goto out;
2900 	}
2901 
2902 	if (bmval2 & FATTR4_WORD2_CHANGE_ATTR_TYPE) {
2903 		p = xdr_reserve_space(xdr, 4);
2904 		if (!p)
2905 			goto out_resource;
2906 		if (IS_I_VERSION(d_inode(dentry)))
2907 			*p++ = cpu_to_be32(NFS4_CHANGE_TYPE_IS_MONOTONIC_INCR);
2908 		else
2909 			*p++ = cpu_to_be32(NFS4_CHANGE_TYPE_IS_TIME_METADATA);
2910 	}
2911 
2912 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2913 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2914 		status = nfsd4_encode_security_label(xdr, rqstp, context,
2915 								contextlen);
2916 		if (status)
2917 			goto out;
2918 	}
2919 #endif
2920 
2921 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
2922 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
2923 	status = nfs_ok;
2924 
2925 out:
2926 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2927 	if (context)
2928 		security_release_secctx(context, contextlen);
2929 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2930 	kfree(acl);
2931 	if (tempfh) {
2932 		fh_put(tempfh);
2933 		kfree(tempfh);
2934 	}
2935 	if (status)
2936 		xdr_truncate_encode(xdr, starting_len);
2937 	return status;
2938 out_nfserr:
2939 	status = nfserrno(err);
2940 	goto out;
2941 out_resource:
2942 	status = nfserr_resource;
2943 	goto out;
2944 }
2945 
2946 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
2947 				struct xdr_buf *buf, __be32 *p, int bytes)
2948 {
2949 	xdr->scratch.iov_len = 0;
2950 	memset(buf, 0, sizeof(struct xdr_buf));
2951 	buf->head[0].iov_base = p;
2952 	buf->head[0].iov_len = 0;
2953 	buf->len = 0;
2954 	xdr->buf = buf;
2955 	xdr->iov = buf->head;
2956 	xdr->p = p;
2957 	xdr->end = (void *)p + bytes;
2958 	buf->buflen = bytes;
2959 }
2960 
2961 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
2962 			struct svc_fh *fhp, struct svc_export *exp,
2963 			struct dentry *dentry, u32 *bmval,
2964 			struct svc_rqst *rqstp, int ignore_crossmnt)
2965 {
2966 	struct xdr_buf dummy;
2967 	struct xdr_stream xdr;
2968 	__be32 ret;
2969 
2970 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
2971 	ret = nfsd4_encode_fattr(&xdr, fhp, exp, dentry, bmval, rqstp,
2972 							ignore_crossmnt);
2973 	*p = xdr.p;
2974 	return ret;
2975 }
2976 
2977 static inline int attributes_need_mount(u32 *bmval)
2978 {
2979 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2980 		return 1;
2981 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2982 		return 1;
2983 	return 0;
2984 }
2985 
2986 static __be32
2987 nfsd4_encode_dirent_fattr(struct xdr_stream *xdr, struct nfsd4_readdir *cd,
2988 			const char *name, int namlen)
2989 {
2990 	struct svc_export *exp = cd->rd_fhp->fh_export;
2991 	struct dentry *dentry;
2992 	__be32 nfserr;
2993 	int ignore_crossmnt = 0;
2994 
2995 	dentry = lookup_one_len_unlocked(name, cd->rd_fhp->fh_dentry, namlen);
2996 	if (IS_ERR(dentry))
2997 		return nfserrno(PTR_ERR(dentry));
2998 	if (d_really_is_negative(dentry)) {
2999 		/*
3000 		 * we're not holding the i_mutex here, so there's
3001 		 * a window where this directory entry could have gone
3002 		 * away.
3003 		 */
3004 		dput(dentry);
3005 		return nfserr_noent;
3006 	}
3007 
3008 	exp_get(exp);
3009 	/*
3010 	 * In the case of a mountpoint, the client may be asking for
3011 	 * attributes that are only properties of the underlying filesystem
3012 	 * as opposed to the cross-mounted file system. In such a case,
3013 	 * we will not follow the cross mount and will fill the attribtutes
3014 	 * directly from the mountpoint dentry.
3015 	 */
3016 	if (nfsd_mountpoint(dentry, exp)) {
3017 		int err;
3018 
3019 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
3020 				&& !attributes_need_mount(cd->rd_bmval)) {
3021 			ignore_crossmnt = 1;
3022 			goto out_encode;
3023 		}
3024 		/*
3025 		 * Why the heck aren't we just using nfsd_lookup??
3026 		 * Different "."/".." handling?  Something else?
3027 		 * At least, add a comment here to explain....
3028 		 */
3029 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
3030 		if (err) {
3031 			nfserr = nfserrno(err);
3032 			goto out_put;
3033 		}
3034 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
3035 		if (nfserr)
3036 			goto out_put;
3037 
3038 	}
3039 out_encode:
3040 	nfserr = nfsd4_encode_fattr(xdr, NULL, exp, dentry, cd->rd_bmval,
3041 					cd->rd_rqstp, ignore_crossmnt);
3042 out_put:
3043 	dput(dentry);
3044 	exp_put(exp);
3045 	return nfserr;
3046 }
3047 
3048 static __be32 *
3049 nfsd4_encode_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
3050 {
3051 	__be32 *p;
3052 
3053 	p = xdr_reserve_space(xdr, 20);
3054 	if (!p)
3055 		return NULL;
3056 	*p++ = htonl(2);
3057 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
3058 	*p++ = htonl(0);			 /* bmval1 */
3059 
3060 	*p++ = htonl(4);     /* attribute length */
3061 	*p++ = nfserr;       /* no htonl */
3062 	return p;
3063 }
3064 
3065 static int
3066 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
3067 		    loff_t offset, u64 ino, unsigned int d_type)
3068 {
3069 	struct readdir_cd *ccd = ccdv;
3070 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
3071 	struct xdr_stream *xdr = cd->xdr;
3072 	int start_offset = xdr->buf->len;
3073 	int cookie_offset;
3074 	u32 name_and_cookie;
3075 	int entry_bytes;
3076 	__be32 nfserr = nfserr_toosmall;
3077 	__be64 wire_offset;
3078 	__be32 *p;
3079 
3080 	/* In nfsv4, "." and ".." never make it onto the wire.. */
3081 	if (name && isdotent(name, namlen)) {
3082 		cd->common.err = nfs_ok;
3083 		return 0;
3084 	}
3085 
3086 	if (cd->cookie_offset) {
3087 		wire_offset = cpu_to_be64(offset);
3088 		write_bytes_to_xdr_buf(xdr->buf, cd->cookie_offset,
3089 							&wire_offset, 8);
3090 	}
3091 
3092 	p = xdr_reserve_space(xdr, 4);
3093 	if (!p)
3094 		goto fail;
3095 	*p++ = xdr_one;                             /* mark entry present */
3096 	cookie_offset = xdr->buf->len;
3097 	p = xdr_reserve_space(xdr, 3*4 + namlen);
3098 	if (!p)
3099 		goto fail;
3100 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
3101 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
3102 
3103 	nfserr = nfsd4_encode_dirent_fattr(xdr, cd, name, namlen);
3104 	switch (nfserr) {
3105 	case nfs_ok:
3106 		break;
3107 	case nfserr_resource:
3108 		nfserr = nfserr_toosmall;
3109 		goto fail;
3110 	case nfserr_noent:
3111 		xdr_truncate_encode(xdr, start_offset);
3112 		goto skip_entry;
3113 	default:
3114 		/*
3115 		 * If the client requested the RDATTR_ERROR attribute,
3116 		 * we stuff the error code into this attribute
3117 		 * and continue.  If this attribute was not requested,
3118 		 * then in accordance with the spec, we fail the
3119 		 * entire READDIR operation(!)
3120 		 */
3121 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
3122 			goto fail;
3123 		p = nfsd4_encode_rdattr_error(xdr, nfserr);
3124 		if (p == NULL) {
3125 			nfserr = nfserr_toosmall;
3126 			goto fail;
3127 		}
3128 	}
3129 	nfserr = nfserr_toosmall;
3130 	entry_bytes = xdr->buf->len - start_offset;
3131 	if (entry_bytes > cd->rd_maxcount)
3132 		goto fail;
3133 	cd->rd_maxcount -= entry_bytes;
3134 	/*
3135 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so
3136 	 * let's always let through the first entry, at least:
3137 	 */
3138 	if (!cd->rd_dircount)
3139 		goto fail;
3140 	name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8;
3141 	if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
3142 		goto fail;
3143 	cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
3144 
3145 	cd->cookie_offset = cookie_offset;
3146 skip_entry:
3147 	cd->common.err = nfs_ok;
3148 	return 0;
3149 fail:
3150 	xdr_truncate_encode(xdr, start_offset);
3151 	cd->common.err = nfserr;
3152 	return -EINVAL;
3153 }
3154 
3155 static __be32
3156 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
3157 {
3158 	__be32 *p;
3159 
3160 	p = xdr_reserve_space(xdr, sizeof(stateid_t));
3161 	if (!p)
3162 		return nfserr_resource;
3163 	*p++ = cpu_to_be32(sid->si_generation);
3164 	p = xdr_encode_opaque_fixed(p, &sid->si_opaque,
3165 					sizeof(stateid_opaque_t));
3166 	return 0;
3167 }
3168 
3169 static __be32
3170 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
3171 {
3172 	struct xdr_stream *xdr = &resp->xdr;
3173 	__be32 *p;
3174 
3175 	p = xdr_reserve_space(xdr, 8);
3176 	if (!p)
3177 		return nfserr_resource;
3178 	*p++ = cpu_to_be32(access->ac_supported);
3179 	*p++ = cpu_to_be32(access->ac_resp_access);
3180 	return 0;
3181 }
3182 
3183 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
3184 {
3185 	struct xdr_stream *xdr = &resp->xdr;
3186 	__be32 *p;
3187 
3188 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 8);
3189 	if (!p)
3190 		return nfserr_resource;
3191 	p = xdr_encode_opaque_fixed(p, bcts->sessionid.data,
3192 					NFS4_MAX_SESSIONID_LEN);
3193 	*p++ = cpu_to_be32(bcts->dir);
3194 	/* Upshifting from TCP to RDMA is not supported */
3195 	*p++ = cpu_to_be32(0);
3196 	return 0;
3197 }
3198 
3199 static __be32
3200 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
3201 {
3202 	struct xdr_stream *xdr = &resp->xdr;
3203 
3204 	return nfsd4_encode_stateid(xdr, &close->cl_stateid);
3205 }
3206 
3207 
3208 static __be32
3209 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
3210 {
3211 	struct xdr_stream *xdr = &resp->xdr;
3212 	__be32 *p;
3213 
3214 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3215 	if (!p)
3216 		return nfserr_resource;
3217 	p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
3218 						NFS4_VERIFIER_SIZE);
3219 	return 0;
3220 }
3221 
3222 static __be32
3223 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
3224 {
3225 	struct xdr_stream *xdr = &resp->xdr;
3226 	__be32 *p;
3227 
3228 	p = xdr_reserve_space(xdr, 20);
3229 	if (!p)
3230 		return nfserr_resource;
3231 	encode_cinfo(p, &create->cr_cinfo);
3232 	nfserr = nfsd4_encode_bitmap(xdr, create->cr_bmval[0],
3233 			create->cr_bmval[1], create->cr_bmval[2]);
3234 	return 0;
3235 }
3236 
3237 static __be32
3238 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
3239 {
3240 	struct svc_fh *fhp = getattr->ga_fhp;
3241 	struct xdr_stream *xdr = &resp->xdr;
3242 
3243 	return nfsd4_encode_fattr(xdr, fhp, fhp->fh_export, fhp->fh_dentry,
3244 				    getattr->ga_bmval, resp->rqstp, 0);
3245 }
3246 
3247 static __be32
3248 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
3249 {
3250 	struct xdr_stream *xdr = &resp->xdr;
3251 	struct svc_fh *fhp = *fhpp;
3252 	unsigned int len;
3253 	__be32 *p;
3254 
3255 	len = fhp->fh_handle.fh_size;
3256 	p = xdr_reserve_space(xdr, len + 4);
3257 	if (!p)
3258 		return nfserr_resource;
3259 	p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base, len);
3260 	return 0;
3261 }
3262 
3263 /*
3264 * Including all fields other than the name, a LOCK4denied structure requires
3265 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
3266 */
3267 static __be32
3268 nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld)
3269 {
3270 	struct xdr_netobj *conf = &ld->ld_owner;
3271 	__be32 *p;
3272 
3273 again:
3274 	p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len));
3275 	if (!p) {
3276 		/*
3277 		 * Don't fail to return the result just because we can't
3278 		 * return the conflicting open:
3279 		 */
3280 		if (conf->len) {
3281 			kfree(conf->data);
3282 			conf->len = 0;
3283 			conf->data = NULL;
3284 			goto again;
3285 		}
3286 		return nfserr_resource;
3287 	}
3288 	p = xdr_encode_hyper(p, ld->ld_start);
3289 	p = xdr_encode_hyper(p, ld->ld_length);
3290 	*p++ = cpu_to_be32(ld->ld_type);
3291 	if (conf->len) {
3292 		p = xdr_encode_opaque_fixed(p, &ld->ld_clientid, 8);
3293 		p = xdr_encode_opaque(p, conf->data, conf->len);
3294 		kfree(conf->data);
3295 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
3296 		p = xdr_encode_hyper(p, (u64)0); /* clientid */
3297 		*p++ = cpu_to_be32(0); /* length of owner name */
3298 	}
3299 	return nfserr_denied;
3300 }
3301 
3302 static __be32
3303 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
3304 {
3305 	struct xdr_stream *xdr = &resp->xdr;
3306 
3307 	if (!nfserr)
3308 		nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid);
3309 	else if (nfserr == nfserr_denied)
3310 		nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied);
3311 
3312 	return nfserr;
3313 }
3314 
3315 static __be32
3316 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
3317 {
3318 	struct xdr_stream *xdr = &resp->xdr;
3319 
3320 	if (nfserr == nfserr_denied)
3321 		nfsd4_encode_lock_denied(xdr, &lockt->lt_denied);
3322 	return nfserr;
3323 }
3324 
3325 static __be32
3326 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
3327 {
3328 	struct xdr_stream *xdr = &resp->xdr;
3329 
3330 	return nfsd4_encode_stateid(xdr, &locku->lu_stateid);
3331 }
3332 
3333 
3334 static __be32
3335 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
3336 {
3337 	struct xdr_stream *xdr = &resp->xdr;
3338 	__be32 *p;
3339 
3340 	p = xdr_reserve_space(xdr, 20);
3341 	if (!p)
3342 		return nfserr_resource;
3343 	p = encode_cinfo(p, &link->li_cinfo);
3344 	return 0;
3345 }
3346 
3347 
3348 static __be32
3349 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
3350 {
3351 	struct xdr_stream *xdr = &resp->xdr;
3352 	__be32 *p;
3353 
3354 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
3355 	if (nfserr)
3356 		return nfserr;
3357 	p = xdr_reserve_space(xdr, 24);
3358 	if (!p)
3359 		return nfserr_resource;
3360 	p = encode_cinfo(p, &open->op_cinfo);
3361 	*p++ = cpu_to_be32(open->op_rflags);
3362 
3363 	nfserr = nfsd4_encode_bitmap(xdr, open->op_bmval[0], open->op_bmval[1],
3364 					open->op_bmval[2]);
3365 	if (nfserr)
3366 		return nfserr;
3367 
3368 	p = xdr_reserve_space(xdr, 4);
3369 	if (!p)
3370 		return nfserr_resource;
3371 
3372 	*p++ = cpu_to_be32(open->op_delegate_type);
3373 	switch (open->op_delegate_type) {
3374 	case NFS4_OPEN_DELEGATE_NONE:
3375 		break;
3376 	case NFS4_OPEN_DELEGATE_READ:
3377 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3378 		if (nfserr)
3379 			return nfserr;
3380 		p = xdr_reserve_space(xdr, 20);
3381 		if (!p)
3382 			return nfserr_resource;
3383 		*p++ = cpu_to_be32(open->op_recall);
3384 
3385 		/*
3386 		 * TODO: ACE's in delegations
3387 		 */
3388 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3389 		*p++ = cpu_to_be32(0);
3390 		*p++ = cpu_to_be32(0);
3391 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3392 		break;
3393 	case NFS4_OPEN_DELEGATE_WRITE:
3394 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3395 		if (nfserr)
3396 			return nfserr;
3397 		p = xdr_reserve_space(xdr, 32);
3398 		if (!p)
3399 			return nfserr_resource;
3400 		*p++ = cpu_to_be32(0);
3401 
3402 		/*
3403 		 * TODO: space_limit's in delegations
3404 		 */
3405 		*p++ = cpu_to_be32(NFS4_LIMIT_SIZE);
3406 		*p++ = cpu_to_be32(~(u32)0);
3407 		*p++ = cpu_to_be32(~(u32)0);
3408 
3409 		/*
3410 		 * TODO: ACE's in delegations
3411 		 */
3412 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3413 		*p++ = cpu_to_be32(0);
3414 		*p++ = cpu_to_be32(0);
3415 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3416 		break;
3417 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
3418 		switch (open->op_why_no_deleg) {
3419 		case WND4_CONTENTION:
3420 		case WND4_RESOURCE:
3421 			p = xdr_reserve_space(xdr, 8);
3422 			if (!p)
3423 				return nfserr_resource;
3424 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3425 			/* deleg signaling not supported yet: */
3426 			*p++ = cpu_to_be32(0);
3427 			break;
3428 		default:
3429 			p = xdr_reserve_space(xdr, 4);
3430 			if (!p)
3431 				return nfserr_resource;
3432 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3433 		}
3434 		break;
3435 	default:
3436 		BUG();
3437 	}
3438 	/* XXX save filehandle here */
3439 	return 0;
3440 }
3441 
3442 static __be32
3443 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
3444 {
3445 	struct xdr_stream *xdr = &resp->xdr;
3446 
3447 	return nfsd4_encode_stateid(xdr, &oc->oc_resp_stateid);
3448 }
3449 
3450 static __be32
3451 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
3452 {
3453 	struct xdr_stream *xdr = &resp->xdr;
3454 
3455 	return nfsd4_encode_stateid(xdr, &od->od_stateid);
3456 }
3457 
3458 static __be32 nfsd4_encode_splice_read(
3459 				struct nfsd4_compoundres *resp,
3460 				struct nfsd4_read *read,
3461 				struct file *file, unsigned long maxcount)
3462 {
3463 	struct xdr_stream *xdr = &resp->xdr;
3464 	struct xdr_buf *buf = xdr->buf;
3465 	u32 eof;
3466 	long len;
3467 	int space_left;
3468 	__be32 nfserr;
3469 	__be32 *p = xdr->p - 2;
3470 
3471 	/* Make sure there will be room for padding if needed */
3472 	if (xdr->end - xdr->p < 1)
3473 		return nfserr_resource;
3474 
3475 	len = maxcount;
3476 	nfserr = nfsd_splice_read(read->rd_rqstp, read->rd_fhp,
3477 				  file, read->rd_offset, &maxcount);
3478 	read->rd_length = maxcount;
3479 	if (nfserr) {
3480 		/*
3481 		 * nfsd_splice_actor may have already messed with the
3482 		 * page length; reset it so as not to confuse
3483 		 * xdr_truncate_encode:
3484 		 */
3485 		buf->page_len = 0;
3486 		return nfserr;
3487 	}
3488 
3489 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3490 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3491 
3492 	*(p++) = htonl(eof);
3493 	*(p++) = htonl(maxcount);
3494 
3495 	buf->page_len = maxcount;
3496 	buf->len += maxcount;
3497 	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
3498 							/ PAGE_SIZE;
3499 
3500 	/* Use rest of head for padding and remaining ops: */
3501 	buf->tail[0].iov_base = xdr->p;
3502 	buf->tail[0].iov_len = 0;
3503 	xdr->iov = buf->tail;
3504 	if (maxcount&3) {
3505 		int pad = 4 - (maxcount&3);
3506 
3507 		*(xdr->p++) = 0;
3508 
3509 		buf->tail[0].iov_base += maxcount&3;
3510 		buf->tail[0].iov_len = pad;
3511 		buf->len += pad;
3512 	}
3513 
3514 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
3515 				buf->buflen - buf->len);
3516 	buf->buflen = buf->len + space_left;
3517 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
3518 
3519 	return 0;
3520 }
3521 
3522 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
3523 				 struct nfsd4_read *read,
3524 				 struct file *file, unsigned long maxcount)
3525 {
3526 	struct xdr_stream *xdr = &resp->xdr;
3527 	u32 eof;
3528 	int v;
3529 	int starting_len = xdr->buf->len - 8;
3530 	long len;
3531 	int thislen;
3532 	__be32 nfserr;
3533 	__be32 tmp;
3534 	__be32 *p;
3535 	u32 zzz = 0;
3536 	int pad;
3537 
3538 	len = maxcount;
3539 	v = 0;
3540 
3541 	thislen = min_t(long, len, ((void *)xdr->end - (void *)xdr->p));
3542 	p = xdr_reserve_space(xdr, (thislen+3)&~3);
3543 	WARN_ON_ONCE(!p);
3544 	resp->rqstp->rq_vec[v].iov_base = p;
3545 	resp->rqstp->rq_vec[v].iov_len = thislen;
3546 	v++;
3547 	len -= thislen;
3548 
3549 	while (len) {
3550 		thislen = min_t(long, len, PAGE_SIZE);
3551 		p = xdr_reserve_space(xdr, (thislen+3)&~3);
3552 		WARN_ON_ONCE(!p);
3553 		resp->rqstp->rq_vec[v].iov_base = p;
3554 		resp->rqstp->rq_vec[v].iov_len = thislen;
3555 		v++;
3556 		len -= thislen;
3557 	}
3558 	read->rd_vlen = v;
3559 
3560 	len = maxcount;
3561 	nfserr = nfsd_readv(resp->rqstp, read->rd_fhp, file, read->rd_offset,
3562 			    resp->rqstp->rq_vec, read->rd_vlen, &maxcount);
3563 	read->rd_length = maxcount;
3564 	if (nfserr)
3565 		return nfserr;
3566 	xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3));
3567 
3568 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3569 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3570 
3571 	tmp = htonl(eof);
3572 	write_bytes_to_xdr_buf(xdr->buf, starting_len    , &tmp, 4);
3573 	tmp = htonl(maxcount);
3574 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
3575 
3576 	pad = (maxcount&3) ? 4 - (maxcount&3) : 0;
3577 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 8 + maxcount,
3578 								&zzz, pad);
3579 	return 0;
3580 
3581 }
3582 
3583 static __be32
3584 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
3585 		  struct nfsd4_read *read)
3586 {
3587 	unsigned long maxcount;
3588 	struct xdr_stream *xdr = &resp->xdr;
3589 	struct file *file = read->rd_filp;
3590 	int starting_len = xdr->buf->len;
3591 	struct raparms *ra = NULL;
3592 	__be32 *p;
3593 
3594 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
3595 	if (!p) {
3596 		WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
3597 		return nfserr_resource;
3598 	}
3599 	if (resp->xdr.buf->page_len &&
3600 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
3601 		WARN_ON_ONCE(1);
3602 		return nfserr_resource;
3603 	}
3604 	xdr_commit_encode(xdr);
3605 
3606 	maxcount = svc_max_payload(resp->rqstp);
3607 	maxcount = min_t(unsigned long, maxcount,
3608 			 (xdr->buf->buflen - xdr->buf->len));
3609 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
3610 
3611 	if (read->rd_tmp_file)
3612 		ra = nfsd_init_raparms(file);
3613 
3614 	if (file->f_op->splice_read &&
3615 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
3616 		nfserr = nfsd4_encode_splice_read(resp, read, file, maxcount);
3617 	else
3618 		nfserr = nfsd4_encode_readv(resp, read, file, maxcount);
3619 
3620 	if (ra)
3621 		nfsd_put_raparams(file, ra);
3622 
3623 	if (nfserr)
3624 		xdr_truncate_encode(xdr, starting_len);
3625 
3626 	return nfserr;
3627 }
3628 
3629 static __be32
3630 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3631 {
3632 	int maxcount;
3633 	__be32 wire_count;
3634 	int zero = 0;
3635 	struct xdr_stream *xdr = &resp->xdr;
3636 	int length_offset = xdr->buf->len;
3637 	__be32 *p;
3638 
3639 	p = xdr_reserve_space(xdr, 4);
3640 	if (!p)
3641 		return nfserr_resource;
3642 	maxcount = PAGE_SIZE;
3643 
3644 	p = xdr_reserve_space(xdr, maxcount);
3645 	if (!p)
3646 		return nfserr_resource;
3647 	/*
3648 	 * XXX: By default, vfs_readlink() will truncate symlinks if they
3649 	 * would overflow the buffer.  Is this kosher in NFSv4?  If not, one
3650 	 * easy fix is: if vfs_readlink() precisely fills the buffer, assume
3651 	 * that truncation occurred, and return NFS4ERR_RESOURCE.
3652 	 */
3653 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
3654 						(char *)p, &maxcount);
3655 	if (nfserr == nfserr_isdir)
3656 		nfserr = nfserr_inval;
3657 	if (nfserr) {
3658 		xdr_truncate_encode(xdr, length_offset);
3659 		return nfserr;
3660 	}
3661 
3662 	wire_count = htonl(maxcount);
3663 	write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
3664 	xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
3665 	if (maxcount & 3)
3666 		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
3667 						&zero, 4 - (maxcount&3));
3668 	return 0;
3669 }
3670 
3671 static __be32
3672 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3673 {
3674 	int maxcount;
3675 	int bytes_left;
3676 	loff_t offset;
3677 	__be64 wire_offset;
3678 	struct xdr_stream *xdr = &resp->xdr;
3679 	int starting_len = xdr->buf->len;
3680 	__be32 *p;
3681 
3682 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3683 	if (!p)
3684 		return nfserr_resource;
3685 
3686 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3687 	*p++ = cpu_to_be32(0);
3688 	*p++ = cpu_to_be32(0);
3689 	resp->xdr.buf->head[0].iov_len = ((char *)resp->xdr.p)
3690 				- (char *)resp->xdr.buf->head[0].iov_base;
3691 
3692 	/*
3693 	 * Number of bytes left for directory entries allowing for the
3694 	 * final 8 bytes of the readdir and a following failed op:
3695 	 */
3696 	bytes_left = xdr->buf->buflen - xdr->buf->len
3697 			- COMPOUND_ERR_SLACK_SPACE - 8;
3698 	if (bytes_left < 0) {
3699 		nfserr = nfserr_resource;
3700 		goto err_no_verf;
3701 	}
3702 	maxcount = svc_max_payload(resp->rqstp);
3703 	maxcount = min_t(u32, readdir->rd_maxcount, maxcount);
3704 	/*
3705 	 * Note the rfc defines rd_maxcount as the size of the
3706 	 * READDIR4resok structure, which includes the verifier above
3707 	 * and the 8 bytes encoded at the end of this function:
3708 	 */
3709 	if (maxcount < 16) {
3710 		nfserr = nfserr_toosmall;
3711 		goto err_no_verf;
3712 	}
3713 	maxcount = min_t(int, maxcount-16, bytes_left);
3714 
3715 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
3716 	if (!readdir->rd_dircount)
3717 		readdir->rd_dircount = svc_max_payload(resp->rqstp);
3718 
3719 	readdir->xdr = xdr;
3720 	readdir->rd_maxcount = maxcount;
3721 	readdir->common.err = 0;
3722 	readdir->cookie_offset = 0;
3723 
3724 	offset = readdir->rd_cookie;
3725 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3726 			      &offset,
3727 			      &readdir->common, nfsd4_encode_dirent);
3728 	if (nfserr == nfs_ok &&
3729 	    readdir->common.err == nfserr_toosmall &&
3730 	    xdr->buf->len == starting_len + 8) {
3731 		/* nothing encoded; which limit did we hit?: */
3732 		if (maxcount - 16 < bytes_left)
3733 			/* It was the fault of rd_maxcount: */
3734 			nfserr = nfserr_toosmall;
3735 		else
3736 			/* We ran out of buffer space: */
3737 			nfserr = nfserr_resource;
3738 	}
3739 	if (nfserr)
3740 		goto err_no_verf;
3741 
3742 	if (readdir->cookie_offset) {
3743 		wire_offset = cpu_to_be64(offset);
3744 		write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset,
3745 							&wire_offset, 8);
3746 	}
3747 
3748 	p = xdr_reserve_space(xdr, 8);
3749 	if (!p) {
3750 		WARN_ON_ONCE(1);
3751 		goto err_no_verf;
3752 	}
3753 	*p++ = 0;	/* no more entries */
3754 	*p++ = htonl(readdir->common.err == nfserr_eof);
3755 
3756 	return 0;
3757 err_no_verf:
3758 	xdr_truncate_encode(xdr, starting_len);
3759 	return nfserr;
3760 }
3761 
3762 static __be32
3763 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3764 {
3765 	struct xdr_stream *xdr = &resp->xdr;
3766 	__be32 *p;
3767 
3768 	p = xdr_reserve_space(xdr, 20);
3769 	if (!p)
3770 		return nfserr_resource;
3771 	p = encode_cinfo(p, &remove->rm_cinfo);
3772 	return 0;
3773 }
3774 
3775 static __be32
3776 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3777 {
3778 	struct xdr_stream *xdr = &resp->xdr;
3779 	__be32 *p;
3780 
3781 	p = xdr_reserve_space(xdr, 40);
3782 	if (!p)
3783 		return nfserr_resource;
3784 	p = encode_cinfo(p, &rename->rn_sinfo);
3785 	p = encode_cinfo(p, &rename->rn_tinfo);
3786 	return 0;
3787 }
3788 
3789 static __be32
3790 nfsd4_do_encode_secinfo(struct xdr_stream *xdr, struct svc_export *exp)
3791 {
3792 	u32 i, nflavs, supported;
3793 	struct exp_flavor_info *flavs;
3794 	struct exp_flavor_info def_flavs[2];
3795 	__be32 *p, *flavorsp;
3796 	static bool report = true;
3797 
3798 	if (exp->ex_nflavors) {
3799 		flavs = exp->ex_flavors;
3800 		nflavs = exp->ex_nflavors;
3801 	} else { /* Handling of some defaults in absence of real secinfo: */
3802 		flavs = def_flavs;
3803 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3804 			nflavs = 2;
3805 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3806 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3807 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3808 			nflavs = 1;
3809 			flavs[0].pseudoflavor
3810 					= svcauth_gss_flavor(exp->ex_client);
3811 		} else {
3812 			nflavs = 1;
3813 			flavs[0].pseudoflavor
3814 					= exp->ex_client->flavour->flavour;
3815 		}
3816 	}
3817 
3818 	supported = 0;
3819 	p = xdr_reserve_space(xdr, 4);
3820 	if (!p)
3821 		return nfserr_resource;
3822 	flavorsp = p++;		/* to be backfilled later */
3823 
3824 	for (i = 0; i < nflavs; i++) {
3825 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
3826 		struct rpcsec_gss_info info;
3827 
3828 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
3829 			supported++;
3830 			p = xdr_reserve_space(xdr, 4 + 4 +
3831 					      XDR_LEN(info.oid.len) + 4 + 4);
3832 			if (!p)
3833 				return nfserr_resource;
3834 			*p++ = cpu_to_be32(RPC_AUTH_GSS);
3835 			p = xdr_encode_opaque(p,  info.oid.data, info.oid.len);
3836 			*p++ = cpu_to_be32(info.qop);
3837 			*p++ = cpu_to_be32(info.service);
3838 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
3839 			supported++;
3840 			p = xdr_reserve_space(xdr, 4);
3841 			if (!p)
3842 				return nfserr_resource;
3843 			*p++ = cpu_to_be32(pf);
3844 		} else {
3845 			if (report)
3846 				pr_warn("NFS: SECINFO: security flavor %u "
3847 					"is not supported\n", pf);
3848 		}
3849 	}
3850 
3851 	if (nflavs != supported)
3852 		report = false;
3853 	*flavorsp = htonl(supported);
3854 	return 0;
3855 }
3856 
3857 static __be32
3858 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3859 		     struct nfsd4_secinfo *secinfo)
3860 {
3861 	struct xdr_stream *xdr = &resp->xdr;
3862 
3863 	return nfsd4_do_encode_secinfo(xdr, secinfo->si_exp);
3864 }
3865 
3866 static __be32
3867 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3868 		     struct nfsd4_secinfo_no_name *secinfo)
3869 {
3870 	struct xdr_stream *xdr = &resp->xdr;
3871 
3872 	return nfsd4_do_encode_secinfo(xdr, secinfo->sin_exp);
3873 }
3874 
3875 /*
3876  * The SETATTR encode routine is special -- it always encodes a bitmap,
3877  * regardless of the error status.
3878  */
3879 static __be32
3880 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3881 {
3882 	struct xdr_stream *xdr = &resp->xdr;
3883 	__be32 *p;
3884 
3885 	p = xdr_reserve_space(xdr, 16);
3886 	if (!p)
3887 		return nfserr_resource;
3888 	if (nfserr) {
3889 		*p++ = cpu_to_be32(3);
3890 		*p++ = cpu_to_be32(0);
3891 		*p++ = cpu_to_be32(0);
3892 		*p++ = cpu_to_be32(0);
3893 	}
3894 	else {
3895 		*p++ = cpu_to_be32(3);
3896 		*p++ = cpu_to_be32(setattr->sa_bmval[0]);
3897 		*p++ = cpu_to_be32(setattr->sa_bmval[1]);
3898 		*p++ = cpu_to_be32(setattr->sa_bmval[2]);
3899 	}
3900 	return nfserr;
3901 }
3902 
3903 static __be32
3904 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3905 {
3906 	struct xdr_stream *xdr = &resp->xdr;
3907 	__be32 *p;
3908 
3909 	if (!nfserr) {
3910 		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
3911 		if (!p)
3912 			return nfserr_resource;
3913 		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
3914 		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
3915 						NFS4_VERIFIER_SIZE);
3916 	}
3917 	else if (nfserr == nfserr_clid_inuse) {
3918 		p = xdr_reserve_space(xdr, 8);
3919 		if (!p)
3920 			return nfserr_resource;
3921 		*p++ = cpu_to_be32(0);
3922 		*p++ = cpu_to_be32(0);
3923 	}
3924 	return nfserr;
3925 }
3926 
3927 static __be32
3928 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3929 {
3930 	struct xdr_stream *xdr = &resp->xdr;
3931 	__be32 *p;
3932 
3933 	p = xdr_reserve_space(xdr, 16);
3934 	if (!p)
3935 		return nfserr_resource;
3936 	*p++ = cpu_to_be32(write->wr_bytes_written);
3937 	*p++ = cpu_to_be32(write->wr_how_written);
3938 	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
3939 						NFS4_VERIFIER_SIZE);
3940 	return 0;
3941 }
3942 
3943 static __be32
3944 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
3945 			 struct nfsd4_exchange_id *exid)
3946 {
3947 	struct xdr_stream *xdr = &resp->xdr;
3948 	__be32 *p;
3949 	char *major_id;
3950 	char *server_scope;
3951 	int major_id_sz;
3952 	int server_scope_sz;
3953 	uint64_t minor_id = 0;
3954 
3955 	major_id = utsname()->nodename;
3956 	major_id_sz = strlen(major_id);
3957 	server_scope = utsname()->nodename;
3958 	server_scope_sz = strlen(server_scope);
3959 
3960 	p = xdr_reserve_space(xdr,
3961 		8 /* eir_clientid */ +
3962 		4 /* eir_sequenceid */ +
3963 		4 /* eir_flags */ +
3964 		4 /* spr_how */);
3965 	if (!p)
3966 		return nfserr_resource;
3967 
3968 	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
3969 	*p++ = cpu_to_be32(exid->seqid);
3970 	*p++ = cpu_to_be32(exid->flags);
3971 
3972 	*p++ = cpu_to_be32(exid->spa_how);
3973 
3974 	switch (exid->spa_how) {
3975 	case SP4_NONE:
3976 		break;
3977 	case SP4_MACH_CRED:
3978 		/* spo_must_enforce bitmap: */
3979 		nfserr = nfsd4_encode_bitmap(xdr,
3980 					exid->spo_must_enforce[0],
3981 					exid->spo_must_enforce[1],
3982 					exid->spo_must_enforce[2]);
3983 		if (nfserr)
3984 			return nfserr;
3985 		/* spo_must_allow bitmap: */
3986 		nfserr = nfsd4_encode_bitmap(xdr,
3987 					exid->spo_must_allow[0],
3988 					exid->spo_must_allow[1],
3989 					exid->spo_must_allow[2]);
3990 		if (nfserr)
3991 			return nfserr;
3992 		break;
3993 	default:
3994 		WARN_ON_ONCE(1);
3995 	}
3996 
3997 	p = xdr_reserve_space(xdr,
3998 		8 /* so_minor_id */ +
3999 		4 /* so_major_id.len */ +
4000 		(XDR_QUADLEN(major_id_sz) * 4) +
4001 		4 /* eir_server_scope.len */ +
4002 		(XDR_QUADLEN(server_scope_sz) * 4) +
4003 		4 /* eir_server_impl_id.count (0) */);
4004 	if (!p)
4005 		return nfserr_resource;
4006 
4007 	/* The server_owner struct */
4008 	p = xdr_encode_hyper(p, minor_id);      /* Minor id */
4009 	/* major id */
4010 	p = xdr_encode_opaque(p, major_id, major_id_sz);
4011 
4012 	/* Server scope */
4013 	p = xdr_encode_opaque(p, server_scope, server_scope_sz);
4014 
4015 	/* Implementation id */
4016 	*p++ = cpu_to_be32(0);	/* zero length nfs_impl_id4 array */
4017 	return 0;
4018 }
4019 
4020 static __be32
4021 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
4022 			    struct nfsd4_create_session *sess)
4023 {
4024 	struct xdr_stream *xdr = &resp->xdr;
4025 	__be32 *p;
4026 
4027 	p = xdr_reserve_space(xdr, 24);
4028 	if (!p)
4029 		return nfserr_resource;
4030 	p = xdr_encode_opaque_fixed(p, sess->sessionid.data,
4031 					NFS4_MAX_SESSIONID_LEN);
4032 	*p++ = cpu_to_be32(sess->seqid);
4033 	*p++ = cpu_to_be32(sess->flags);
4034 
4035 	p = xdr_reserve_space(xdr, 28);
4036 	if (!p)
4037 		return nfserr_resource;
4038 	*p++ = cpu_to_be32(0); /* headerpadsz */
4039 	*p++ = cpu_to_be32(sess->fore_channel.maxreq_sz);
4040 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_sz);
4041 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_cached);
4042 	*p++ = cpu_to_be32(sess->fore_channel.maxops);
4043 	*p++ = cpu_to_be32(sess->fore_channel.maxreqs);
4044 	*p++ = cpu_to_be32(sess->fore_channel.nr_rdma_attrs);
4045 
4046 	if (sess->fore_channel.nr_rdma_attrs) {
4047 		p = xdr_reserve_space(xdr, 4);
4048 		if (!p)
4049 			return nfserr_resource;
4050 		*p++ = cpu_to_be32(sess->fore_channel.rdma_attrs);
4051 	}
4052 
4053 	p = xdr_reserve_space(xdr, 28);
4054 	if (!p)
4055 		return nfserr_resource;
4056 	*p++ = cpu_to_be32(0); /* headerpadsz */
4057 	*p++ = cpu_to_be32(sess->back_channel.maxreq_sz);
4058 	*p++ = cpu_to_be32(sess->back_channel.maxresp_sz);
4059 	*p++ = cpu_to_be32(sess->back_channel.maxresp_cached);
4060 	*p++ = cpu_to_be32(sess->back_channel.maxops);
4061 	*p++ = cpu_to_be32(sess->back_channel.maxreqs);
4062 	*p++ = cpu_to_be32(sess->back_channel.nr_rdma_attrs);
4063 
4064 	if (sess->back_channel.nr_rdma_attrs) {
4065 		p = xdr_reserve_space(xdr, 4);
4066 		if (!p)
4067 			return nfserr_resource;
4068 		*p++ = cpu_to_be32(sess->back_channel.rdma_attrs);
4069 	}
4070 	return 0;
4071 }
4072 
4073 static __be32
4074 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
4075 		      struct nfsd4_sequence *seq)
4076 {
4077 	struct xdr_stream *xdr = &resp->xdr;
4078 	__be32 *p;
4079 
4080 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 20);
4081 	if (!p)
4082 		return nfserr_resource;
4083 	p = xdr_encode_opaque_fixed(p, seq->sessionid.data,
4084 					NFS4_MAX_SESSIONID_LEN);
4085 	*p++ = cpu_to_be32(seq->seqid);
4086 	*p++ = cpu_to_be32(seq->slotid);
4087 	/* Note slotid's are numbered from zero: */
4088 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_highest_slotid */
4089 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_target_highest_slotid */
4090 	*p++ = cpu_to_be32(seq->status_flags);
4091 
4092 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
4093 	return 0;
4094 }
4095 
4096 static __be32
4097 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
4098 			  struct nfsd4_test_stateid *test_stateid)
4099 {
4100 	struct xdr_stream *xdr = &resp->xdr;
4101 	struct nfsd4_test_stateid_id *stateid, *next;
4102 	__be32 *p;
4103 
4104 	p = xdr_reserve_space(xdr, 4 + (4 * test_stateid->ts_num_ids));
4105 	if (!p)
4106 		return nfserr_resource;
4107 	*p++ = htonl(test_stateid->ts_num_ids);
4108 
4109 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
4110 		*p++ = stateid->ts_id_status;
4111 	}
4112 
4113 	return 0;
4114 }
4115 
4116 #ifdef CONFIG_NFSD_PNFS
4117 static __be32
4118 nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
4119 		struct nfsd4_getdeviceinfo *gdev)
4120 {
4121 	struct xdr_stream *xdr = &resp->xdr;
4122 	const struct nfsd4_layout_ops *ops;
4123 	u32 starting_len = xdr->buf->len, needed_len;
4124 	__be32 *p;
4125 
4126 	p = xdr_reserve_space(xdr, 4);
4127 	if (!p)
4128 		return nfserr_resource;
4129 
4130 	*p++ = cpu_to_be32(gdev->gd_layout_type);
4131 
4132 	/* If maxcount is 0 then just update notifications */
4133 	if (gdev->gd_maxcount != 0) {
4134 		ops = nfsd4_layout_ops[gdev->gd_layout_type];
4135 		nfserr = ops->encode_getdeviceinfo(xdr, gdev);
4136 		if (nfserr) {
4137 			/*
4138 			 * We don't bother to burden the layout drivers with
4139 			 * enforcing gd_maxcount, just tell the client to
4140 			 * come back with a bigger buffer if it's not enough.
4141 			 */
4142 			if (xdr->buf->len + 4 > gdev->gd_maxcount)
4143 				goto toosmall;
4144 			return nfserr;
4145 		}
4146 	}
4147 
4148 	if (gdev->gd_notify_types) {
4149 		p = xdr_reserve_space(xdr, 4 + 4);
4150 		if (!p)
4151 			return nfserr_resource;
4152 		*p++ = cpu_to_be32(1);			/* bitmap length */
4153 		*p++ = cpu_to_be32(gdev->gd_notify_types);
4154 	} else {
4155 		p = xdr_reserve_space(xdr, 4);
4156 		if (!p)
4157 			return nfserr_resource;
4158 		*p++ = 0;
4159 	}
4160 
4161 	return 0;
4162 toosmall:
4163 	dprintk("%s: maxcount too small\n", __func__);
4164 	needed_len = xdr->buf->len + 4 /* notifications */;
4165 	xdr_truncate_encode(xdr, starting_len);
4166 	p = xdr_reserve_space(xdr, 4);
4167 	if (!p)
4168 		return nfserr_resource;
4169 	*p++ = cpu_to_be32(needed_len);
4170 	return nfserr_toosmall;
4171 }
4172 
4173 static __be32
4174 nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr,
4175 		struct nfsd4_layoutget *lgp)
4176 {
4177 	struct xdr_stream *xdr = &resp->xdr;
4178 	const struct nfsd4_layout_ops *ops;
4179 	__be32 *p;
4180 
4181 	p = xdr_reserve_space(xdr, 36 + sizeof(stateid_opaque_t));
4182 	if (!p)
4183 		return nfserr_resource;
4184 
4185 	*p++ = cpu_to_be32(1);	/* we always set return-on-close */
4186 	*p++ = cpu_to_be32(lgp->lg_sid.si_generation);
4187 	p = xdr_encode_opaque_fixed(p, &lgp->lg_sid.si_opaque,
4188 				    sizeof(stateid_opaque_t));
4189 
4190 	*p++ = cpu_to_be32(1);	/* we always return a single layout */
4191 	p = xdr_encode_hyper(p, lgp->lg_seg.offset);
4192 	p = xdr_encode_hyper(p, lgp->lg_seg.length);
4193 	*p++ = cpu_to_be32(lgp->lg_seg.iomode);
4194 	*p++ = cpu_to_be32(lgp->lg_layout_type);
4195 
4196 	ops = nfsd4_layout_ops[lgp->lg_layout_type];
4197 	return ops->encode_layoutget(xdr, lgp);
4198 }
4199 
4200 static __be32
4201 nfsd4_encode_layoutcommit(struct nfsd4_compoundres *resp, __be32 nfserr,
4202 			  struct nfsd4_layoutcommit *lcp)
4203 {
4204 	struct xdr_stream *xdr = &resp->xdr;
4205 	__be32 *p;
4206 
4207 	p = xdr_reserve_space(xdr, 4);
4208 	if (!p)
4209 		return nfserr_resource;
4210 	*p++ = cpu_to_be32(lcp->lc_size_chg);
4211 	if (lcp->lc_size_chg) {
4212 		p = xdr_reserve_space(xdr, 8);
4213 		if (!p)
4214 			return nfserr_resource;
4215 		p = xdr_encode_hyper(p, lcp->lc_newsize);
4216 	}
4217 
4218 	return 0;
4219 }
4220 
4221 static __be32
4222 nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
4223 		struct nfsd4_layoutreturn *lrp)
4224 {
4225 	struct xdr_stream *xdr = &resp->xdr;
4226 	__be32 *p;
4227 
4228 	p = xdr_reserve_space(xdr, 4);
4229 	if (!p)
4230 		return nfserr_resource;
4231 	*p++ = cpu_to_be32(lrp->lrs_present);
4232 	if (lrp->lrs_present)
4233 		return nfsd4_encode_stateid(xdr, &lrp->lr_sid);
4234 	return 0;
4235 }
4236 #endif /* CONFIG_NFSD_PNFS */
4237 
4238 static __be32
4239 nfsd42_encode_write_res(struct nfsd4_compoundres *resp,
4240 		struct nfsd42_write_res *write, bool sync)
4241 {
4242 	__be32 *p;
4243 	p = xdr_reserve_space(&resp->xdr, 4);
4244 	if (!p)
4245 		return nfserr_resource;
4246 
4247 	if (sync)
4248 		*p++ = cpu_to_be32(0);
4249 	else {
4250 		__be32 nfserr;
4251 		*p++ = cpu_to_be32(1);
4252 		nfserr = nfsd4_encode_stateid(&resp->xdr, &write->cb_stateid);
4253 		if (nfserr)
4254 			return nfserr;
4255 	}
4256 	p = xdr_reserve_space(&resp->xdr, 8 + 4 + NFS4_VERIFIER_SIZE);
4257 	if (!p)
4258 		return nfserr_resource;
4259 
4260 	p = xdr_encode_hyper(p, write->wr_bytes_written);
4261 	*p++ = cpu_to_be32(write->wr_stable_how);
4262 	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
4263 				    NFS4_VERIFIER_SIZE);
4264 	return nfs_ok;
4265 }
4266 
4267 static __be32
4268 nfsd4_encode_copy(struct nfsd4_compoundres *resp, __be32 nfserr,
4269 		  struct nfsd4_copy *copy)
4270 {
4271 	__be32 *p;
4272 
4273 	nfserr = nfsd42_encode_write_res(resp, &copy->cp_res,
4274 			copy->cp_synchronous);
4275 	if (nfserr)
4276 		return nfserr;
4277 
4278 	p = xdr_reserve_space(&resp->xdr, 4 + 4);
4279 	*p++ = xdr_one; /* cr_consecutive */
4280 	*p++ = cpu_to_be32(copy->cp_synchronous);
4281 	return 0;
4282 }
4283 
4284 static __be32
4285 nfsd4_encode_offload_status(struct nfsd4_compoundres *resp, __be32 nfserr,
4286 			    struct nfsd4_offload_status *os)
4287 {
4288 	struct xdr_stream *xdr = &resp->xdr;
4289 	__be32 *p;
4290 
4291 	p = xdr_reserve_space(xdr, 8 + 4);
4292 	if (!p)
4293 		return nfserr_resource;
4294 	p = xdr_encode_hyper(p, os->count);
4295 	*p++ = cpu_to_be32(0);
4296 
4297 	return nfserr;
4298 }
4299 
4300 static __be32
4301 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
4302 		  struct nfsd4_seek *seek)
4303 {
4304 	__be32 *p;
4305 
4306 	p = xdr_reserve_space(&resp->xdr, 4 + 8);
4307 	*p++ = cpu_to_be32(seek->seek_eof);
4308 	p = xdr_encode_hyper(p, seek->seek_pos);
4309 
4310 	return 0;
4311 }
4312 
4313 static __be32
4314 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
4315 {
4316 	return nfserr;
4317 }
4318 
4319 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
4320 
4321 /*
4322  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
4323  * since we don't need to filter out obsolete ops as this is
4324  * done in the decoding phase.
4325  */
4326 static const nfsd4_enc nfsd4_enc_ops[] = {
4327 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
4328 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
4329 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
4330 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
4331 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
4332 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4333 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
4334 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
4335 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
4336 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
4337 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
4338 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
4339 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
4340 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
4341 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4342 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
4343 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
4344 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
4345 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
4346 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4347 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
4348 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4349 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
4350 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
4351 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
4352 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
4353 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
4354 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
4355 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
4356 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
4357 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
4358 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
4359 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
4360 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
4361 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4362 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
4363 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
4364 
4365 	/* NFSv4.1 operations */
4366 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
4367 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
4368 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
4369 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
4370 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
4371 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
4372 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4373 #ifdef CONFIG_NFSD_PNFS
4374 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_getdeviceinfo,
4375 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4376 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_layoutcommit,
4377 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_layoutget,
4378 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_layoutreturn,
4379 #else
4380 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
4381 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4382 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
4383 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
4384 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4385 #endif
4386 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
4387 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
4388 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
4389 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
4390 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4391 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
4392 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
4393 
4394 	/* NFSv4.2 operations */
4395 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4396 	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_copy,
4397 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
4398 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4399 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
4400 	[OP_LAYOUTERROR]	= (nfsd4_enc)nfsd4_encode_noop,
4401 	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,
4402 	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,
4403 	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_offload_status,
4404 	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_noop,
4405 	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,
4406 	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,
4407 	[OP_CLONE]		= (nfsd4_enc)nfsd4_encode_noop,
4408 };
4409 
4410 /*
4411  * Calculate whether we still have space to encode repsize bytes.
4412  * There are two considerations:
4413  *     - For NFS versions >=4.1, the size of the reply must stay within
4414  *       session limits
4415  *     - For all NFS versions, we must stay within limited preallocated
4416  *       buffer space.
4417  *
4418  * This is called before the operation is processed, so can only provide
4419  * an upper estimate.  For some nonidempotent operations (such as
4420  * getattr), it's not necessarily a problem if that estimate is wrong,
4421  * as we can fail it after processing without significant side effects.
4422  */
4423 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
4424 {
4425 	struct xdr_buf *buf = &resp->rqstp->rq_res;
4426 	struct nfsd4_slot *slot = resp->cstate.slot;
4427 
4428 	if (buf->len + respsize <= buf->buflen)
4429 		return nfs_ok;
4430 	if (!nfsd4_has_session(&resp->cstate))
4431 		return nfserr_resource;
4432 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
4433 		WARN_ON_ONCE(1);
4434 		return nfserr_rep_too_big_to_cache;
4435 	}
4436 	return nfserr_rep_too_big;
4437 }
4438 
4439 void
4440 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
4441 {
4442 	struct xdr_stream *xdr = &resp->xdr;
4443 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
4444 	struct svc_rqst *rqstp = resp->rqstp;
4445 	const struct nfsd4_operation *opdesc = op->opdesc;
4446 	int post_err_offset;
4447 	nfsd4_enc encoder;
4448 	__be32 *p;
4449 
4450 	p = xdr_reserve_space(xdr, 8);
4451 	if (!p) {
4452 		WARN_ON_ONCE(1);
4453 		return;
4454 	}
4455 	*p++ = cpu_to_be32(op->opnum);
4456 	post_err_offset = xdr->buf->len;
4457 
4458 	if (op->opnum == OP_ILLEGAL)
4459 		goto status;
4460 	if (op->status && opdesc &&
4461 			!(opdesc->op_flags & OP_NONTRIVIAL_ERROR_ENCODE))
4462 		goto status;
4463 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
4464 	       !nfsd4_enc_ops[op->opnum]);
4465 	encoder = nfsd4_enc_ops[op->opnum];
4466 	op->status = encoder(resp, op->status, &op->u);
4467 	if (opdesc && opdesc->op_release)
4468 		opdesc->op_release(&op->u);
4469 	xdr_commit_encode(xdr);
4470 
4471 	/* nfsd4_check_resp_size guarantees enough room for error status */
4472 	if (!op->status) {
4473 		int space_needed = 0;
4474 		if (!nfsd4_last_compound_op(rqstp))
4475 			space_needed = COMPOUND_ERR_SLACK_SPACE;
4476 		op->status = nfsd4_check_resp_size(resp, space_needed);
4477 	}
4478 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
4479 		struct nfsd4_slot *slot = resp->cstate.slot;
4480 
4481 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
4482 			op->status = nfserr_rep_too_big_to_cache;
4483 		else
4484 			op->status = nfserr_rep_too_big;
4485 	}
4486 	if (op->status == nfserr_resource ||
4487 	    op->status == nfserr_rep_too_big ||
4488 	    op->status == nfserr_rep_too_big_to_cache) {
4489 		/*
4490 		 * The operation may have already been encoded or
4491 		 * partially encoded.  No op returns anything additional
4492 		 * in the case of one of these three errors, so we can
4493 		 * just truncate back to after the status.  But it's a
4494 		 * bug if we had to do this on a non-idempotent op:
4495 		 */
4496 		warn_on_nonidempotent_op(op);
4497 		xdr_truncate_encode(xdr, post_err_offset);
4498 	}
4499 	if (so) {
4500 		int len = xdr->buf->len - post_err_offset;
4501 
4502 		so->so_replay.rp_status = op->status;
4503 		so->so_replay.rp_buflen = len;
4504 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
4505 						so->so_replay.rp_buf, len);
4506 	}
4507 status:
4508 	/* Note that op->status is already in network byte order: */
4509 	write_bytes_to_xdr_buf(xdr->buf, post_err_offset - 4, &op->status, 4);
4510 }
4511 
4512 /*
4513  * Encode the reply stored in the stateowner reply cache
4514  *
4515  * XDR note: do not encode rp->rp_buflen: the buffer contains the
4516  * previously sent already encoded operation.
4517  */
4518 void
4519 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
4520 {
4521 	__be32 *p;
4522 	struct nfs4_replay *rp = op->replay;
4523 
4524 	BUG_ON(!rp);
4525 
4526 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
4527 	if (!p) {
4528 		WARN_ON_ONCE(1);
4529 		return;
4530 	}
4531 	*p++ = cpu_to_be32(op->opnum);
4532 	*p++ = rp->rp_status;  /* already xdr'ed */
4533 
4534 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
4535 }
4536 
4537 int
4538 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p)
4539 {
4540         return xdr_ressize_check(rqstp, p);
4541 }
4542 
4543 void nfsd4_release_compoundargs(struct svc_rqst *rqstp)
4544 {
4545 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4546 
4547 	if (args->ops != args->iops) {
4548 		kfree(args->ops);
4549 		args->ops = args->iops;
4550 	}
4551 	kfree(args->tmpp);
4552 	args->tmpp = NULL;
4553 	while (args->to_free) {
4554 		struct svcxdr_tmpbuf *tb = args->to_free;
4555 		args->to_free = tb->next;
4556 		kfree(tb);
4557 	}
4558 }
4559 
4560 int
4561 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p)
4562 {
4563 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4564 
4565 	if (rqstp->rq_arg.head[0].iov_len % 4) {
4566 		/* client is nuts */
4567 		dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)",
4568 			__func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid));
4569 		return 0;
4570 	}
4571 	args->p = p;
4572 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
4573 	args->pagelist = rqstp->rq_arg.pages;
4574 	args->pagelen = rqstp->rq_arg.page_len;
4575 	args->tail = false;
4576 	args->tmpp = NULL;
4577 	args->to_free = NULL;
4578 	args->ops = args->iops;
4579 	args->rqstp = rqstp;
4580 
4581 	return !nfsd4_decode_compound(args);
4582 }
4583 
4584 int
4585 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p)
4586 {
4587 	/*
4588 	 * All that remains is to write the tag and operation count...
4589 	 */
4590 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
4591 	struct xdr_buf *buf = resp->xdr.buf;
4592 
4593 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
4594 				 buf->tail[0].iov_len);
4595 
4596 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
4597 
4598 	p = resp->tagp;
4599 	*p++ = htonl(resp->taglen);
4600 	memcpy(p, resp->tag, resp->taglen);
4601 	p += XDR_QUADLEN(resp->taglen);
4602 	*p++ = htonl(resp->opcnt);
4603 
4604 	nfsd4_sequence_done(resp);
4605 	return 1;
4606 }
4607 
4608 /*
4609  * Local variables:
4610  *  c-basic-offset: 8
4611  * End:
4612  */
4613