xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision 3cea11cd)
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 #include <linux/sunrpc/addr.h>
44 #include <linux/xattr.h>
45 #include <uapi/linux/xattr.h>
46 
47 #include "idmap.h"
48 #include "acl.h"
49 #include "xdr4.h"
50 #include "vfs.h"
51 #include "state.h"
52 #include "cache.h"
53 #include "netns.h"
54 #include "pnfs.h"
55 #include "filecache.h"
56 
57 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
58 #include <linux/security.h>
59 #endif
60 
61 
62 #define NFSDDBG_FACILITY		NFSDDBG_XDR
63 
64 const u32 nfsd_suppattrs[3][3] = {
65 	{NFSD4_SUPPORTED_ATTRS_WORD0,
66 	 NFSD4_SUPPORTED_ATTRS_WORD1,
67 	 NFSD4_SUPPORTED_ATTRS_WORD2},
68 
69 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
70 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
71 	 NFSD4_1_SUPPORTED_ATTRS_WORD2},
72 
73 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
74 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
75 	 NFSD4_2_SUPPORTED_ATTRS_WORD2},
76 };
77 
78 /*
79  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
80  * directory in order to indicate to the client that a filesystem boundary is present
81  * We use a fixed fsid for a referral
82  */
83 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
84 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
85 
86 static __be32
87 check_filename(char *str, int len)
88 {
89 	int i;
90 
91 	if (len == 0)
92 		return nfserr_inval;
93 	if (isdotent(str, len))
94 		return nfserr_badname;
95 	for (i = 0; i < len; i++)
96 		if (str[i] == '/')
97 			return nfserr_badname;
98 	return 0;
99 }
100 
101 #define DECODE_HEAD				\
102 	__be32 *p;				\
103 	__be32 status
104 #define DECODE_TAIL				\
105 	status = 0;				\
106 out:						\
107 	return status;				\
108 xdr_error:					\
109 	dprintk("NFSD: xdr error (%s:%d)\n",	\
110 			__FILE__, __LINE__);	\
111 	status = nfserr_bad_xdr;		\
112 	goto out
113 
114 #define READMEM(x,nbytes) do {			\
115 	x = (char *)p;				\
116 	p += XDR_QUADLEN(nbytes);		\
117 } while (0)
118 #define SAVEMEM(x,nbytes) do {			\
119 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
120  		savemem(argp, p, nbytes) :	\
121  		(char *)p)) {			\
122 		dprintk("NFSD: xdr error (%s:%d)\n", \
123 				__FILE__, __LINE__); \
124 		goto xdr_error;			\
125 		}				\
126 	p += XDR_QUADLEN(nbytes);		\
127 } while (0)
128 #define COPYMEM(x,nbytes) do {			\
129 	memcpy((x), p, nbytes);			\
130 	p += XDR_QUADLEN(nbytes);		\
131 } while (0)
132 
133 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
134 #define READ_BUF(nbytes)  do {			\
135 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
136 		p = argp->p;			\
137 		argp->p += XDR_QUADLEN(nbytes);	\
138 	} else if (!(p = read_buf(argp, nbytes))) { \
139 		dprintk("NFSD: xdr error (%s:%d)\n", \
140 				__FILE__, __LINE__); \
141 		goto xdr_error;			\
142 	}					\
143 } while (0)
144 
145 static void next_decode_page(struct nfsd4_compoundargs *argp)
146 {
147 	argp->p = page_address(argp->pagelist[0]);
148 	argp->pagelist++;
149 	if (argp->pagelen < PAGE_SIZE) {
150 		argp->end = argp->p + XDR_QUADLEN(argp->pagelen);
151 		argp->pagelen = 0;
152 	} else {
153 		argp->end = argp->p + (PAGE_SIZE>>2);
154 		argp->pagelen -= PAGE_SIZE;
155 	}
156 }
157 
158 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
159 {
160 	/* We want more bytes than seem to be available.
161 	 * Maybe we need a new page, maybe we have just run out
162 	 */
163 	unsigned int avail = (char *)argp->end - (char *)argp->p;
164 	__be32 *p;
165 
166 	if (argp->pagelen == 0) {
167 		struct kvec *vec = &argp->rqstp->rq_arg.tail[0];
168 
169 		if (!argp->tail) {
170 			argp->tail = true;
171 			avail = vec->iov_len;
172 			argp->p = vec->iov_base;
173 			argp->end = vec->iov_base + avail;
174 		}
175 
176 		if (avail < nbytes)
177 			return NULL;
178 
179 		p = argp->p;
180 		argp->p += XDR_QUADLEN(nbytes);
181 		return p;
182 	}
183 
184 	if (avail + argp->pagelen < nbytes)
185 		return NULL;
186 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
187 		return NULL;
188 	/* ok, we can do it with the current plus the next page */
189 	if (nbytes <= sizeof(argp->tmp))
190 		p = argp->tmp;
191 	else {
192 		kfree(argp->tmpp);
193 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
194 		if (!p)
195 			return NULL;
196 
197 	}
198 	/*
199 	 * The following memcpy is safe because read_buf is always
200 	 * called with nbytes > avail, and the two cases above both
201 	 * guarantee p points to at least nbytes bytes.
202 	 */
203 	memcpy(p, argp->p, avail);
204 	next_decode_page(argp);
205 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
206 	argp->p += XDR_QUADLEN(nbytes - avail);
207 	return p;
208 }
209 
210 static unsigned int compoundargs_bytes_left(struct nfsd4_compoundargs *argp)
211 {
212 	unsigned int this = (char *)argp->end - (char *)argp->p;
213 
214 	return this + argp->pagelen;
215 }
216 
217 static int zero_clientid(clientid_t *clid)
218 {
219 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
220 }
221 
222 /**
223  * svcxdr_tmpalloc - allocate memory to be freed after compound processing
224  * @argp: NFSv4 compound argument structure
225  * @len: length of buffer to allocate
226  *
227  * Allocates a buffer of size @len to be freed when processing the compound
228  * operation described in @argp finishes.
229  */
230 static void *
231 svcxdr_tmpalloc(struct nfsd4_compoundargs *argp, u32 len)
232 {
233 	struct svcxdr_tmpbuf *tb;
234 
235 	tb = kmalloc(sizeof(*tb) + len, GFP_KERNEL);
236 	if (!tb)
237 		return NULL;
238 	tb->next = argp->to_free;
239 	argp->to_free = tb;
240 	return tb->buf;
241 }
242 
243 /*
244  * For xdr strings that need to be passed to other kernel api's
245  * as null-terminated strings.
246  *
247  * Note null-terminating in place usually isn't safe since the
248  * buffer might end on a page boundary.
249  */
250 static char *
251 svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len)
252 {
253 	char *p = svcxdr_tmpalloc(argp, len + 1);
254 
255 	if (!p)
256 		return NULL;
257 	memcpy(p, buf, len);
258 	p[len] = '\0';
259 	return p;
260 }
261 
262 static __be32
263 svcxdr_construct_vector(struct nfsd4_compoundargs *argp, struct kvec *head,
264 			struct page ***pagelist, u32 buflen)
265 {
266 	int avail;
267 	int len;
268 	int pages;
269 
270 	/* Sorry .. no magic macros for this.. *
271 	 * READ_BUF(write->wr_buflen);
272 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
273 	 */
274 	avail = (char *)argp->end - (char *)argp->p;
275 	if (avail + argp->pagelen < buflen) {
276 		dprintk("NFSD: xdr error (%s:%d)\n",
277 			       __FILE__, __LINE__);
278 		return nfserr_bad_xdr;
279 	}
280 	head->iov_base = argp->p;
281 	head->iov_len = avail;
282 	*pagelist = argp->pagelist;
283 
284 	len = XDR_QUADLEN(buflen) << 2;
285 	if (len >= avail) {
286 		len -= avail;
287 
288 		pages = len >> PAGE_SHIFT;
289 		argp->pagelist += pages;
290 		argp->pagelen -= pages * PAGE_SIZE;
291 		len -= pages * PAGE_SIZE;
292 
293 		next_decode_page(argp);
294 	}
295 	argp->p += XDR_QUADLEN(len);
296 
297 	return 0;
298 }
299 
300 /**
301  * savemem - duplicate a chunk of memory for later processing
302  * @argp: NFSv4 compound argument structure to be freed with
303  * @p: pointer to be duplicated
304  * @nbytes: length to be duplicated
305  *
306  * Returns a pointer to a copy of @nbytes bytes of memory at @p
307  * that are preserved until processing of the NFSv4 compound
308  * operation described by @argp finishes.
309  */
310 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
311 {
312 	void *ret;
313 
314 	ret = svcxdr_tmpalloc(argp, nbytes);
315 	if (!ret)
316 		return NULL;
317 	memcpy(ret, p, nbytes);
318 	return ret;
319 }
320 
321 static __be32
322 nfsd4_decode_time(struct nfsd4_compoundargs *argp, struct timespec64 *tv)
323 {
324 	DECODE_HEAD;
325 
326 	READ_BUF(12);
327 	p = xdr_decode_hyper(p, &tv->tv_sec);
328 	tv->tv_nsec = be32_to_cpup(p++);
329 	if (tv->tv_nsec >= (u32)1000000000)
330 		return nfserr_inval;
331 
332 	DECODE_TAIL;
333 }
334 
335 static __be32
336 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
337 {
338 	u32 bmlen;
339 	DECODE_HEAD;
340 
341 	bmval[0] = 0;
342 	bmval[1] = 0;
343 	bmval[2] = 0;
344 
345 	READ_BUF(4);
346 	bmlen = be32_to_cpup(p++);
347 	if (bmlen > 1000)
348 		goto xdr_error;
349 
350 	READ_BUF(bmlen << 2);
351 	if (bmlen > 0)
352 		bmval[0] = be32_to_cpup(p++);
353 	if (bmlen > 1)
354 		bmval[1] = be32_to_cpup(p++);
355 	if (bmlen > 2)
356 		bmval[2] = be32_to_cpup(p++);
357 
358 	DECODE_TAIL;
359 }
360 
361 static __be32
362 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
363 		   struct iattr *iattr, struct nfs4_acl **acl,
364 		   struct xdr_netobj *label, int *umask)
365 {
366 	int expected_len, len = 0;
367 	u32 dummy32;
368 	char *buf;
369 
370 	DECODE_HEAD;
371 	iattr->ia_valid = 0;
372 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
373 		return status;
374 
375 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
376 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
377 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2) {
378 		if (nfsd_attrs_supported(argp->minorversion, bmval))
379 			return nfserr_inval;
380 		return nfserr_attrnotsupp;
381 	}
382 
383 	READ_BUF(4);
384 	expected_len = be32_to_cpup(p++);
385 
386 	if (bmval[0] & FATTR4_WORD0_SIZE) {
387 		READ_BUF(8);
388 		len += 8;
389 		p = xdr_decode_hyper(p, &iattr->ia_size);
390 		iattr->ia_valid |= ATTR_SIZE;
391 	}
392 	if (bmval[0] & FATTR4_WORD0_ACL) {
393 		u32 nace;
394 		struct nfs4_ace *ace;
395 
396 		READ_BUF(4); len += 4;
397 		nace = be32_to_cpup(p++);
398 
399 		if (nace > compoundargs_bytes_left(argp)/20)
400 			/*
401 			 * Even with 4-byte names there wouldn't be
402 			 * space for that many aces; something fishy is
403 			 * going on:
404 			 */
405 			return nfserr_fbig;
406 
407 		*acl = svcxdr_tmpalloc(argp, nfs4_acl_bytes(nace));
408 		if (*acl == NULL)
409 			return nfserr_jukebox;
410 
411 		(*acl)->naces = nace;
412 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
413 			READ_BUF(16); len += 16;
414 			ace->type = be32_to_cpup(p++);
415 			ace->flag = be32_to_cpup(p++);
416 			ace->access_mask = be32_to_cpup(p++);
417 			dummy32 = be32_to_cpup(p++);
418 			READ_BUF(dummy32);
419 			len += XDR_QUADLEN(dummy32) << 2;
420 			READMEM(buf, dummy32);
421 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
422 			status = nfs_ok;
423 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
424 				;
425 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
426 				status = nfsd_map_name_to_gid(argp->rqstp,
427 						buf, dummy32, &ace->who_gid);
428 			else
429 				status = nfsd_map_name_to_uid(argp->rqstp,
430 						buf, dummy32, &ace->who_uid);
431 			if (status)
432 				return status;
433 		}
434 	} else
435 		*acl = NULL;
436 	if (bmval[1] & FATTR4_WORD1_MODE) {
437 		READ_BUF(4);
438 		len += 4;
439 		iattr->ia_mode = be32_to_cpup(p++);
440 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
441 		iattr->ia_valid |= ATTR_MODE;
442 	}
443 	if (bmval[1] & FATTR4_WORD1_OWNER) {
444 		READ_BUF(4);
445 		len += 4;
446 		dummy32 = be32_to_cpup(p++);
447 		READ_BUF(dummy32);
448 		len += (XDR_QUADLEN(dummy32) << 2);
449 		READMEM(buf, dummy32);
450 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
451 			return status;
452 		iattr->ia_valid |= ATTR_UID;
453 	}
454 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
455 		READ_BUF(4);
456 		len += 4;
457 		dummy32 = be32_to_cpup(p++);
458 		READ_BUF(dummy32);
459 		len += (XDR_QUADLEN(dummy32) << 2);
460 		READMEM(buf, dummy32);
461 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
462 			return status;
463 		iattr->ia_valid |= ATTR_GID;
464 	}
465 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
466 		READ_BUF(4);
467 		len += 4;
468 		dummy32 = be32_to_cpup(p++);
469 		switch (dummy32) {
470 		case NFS4_SET_TO_CLIENT_TIME:
471 			len += 12;
472 			status = nfsd4_decode_time(argp, &iattr->ia_atime);
473 			if (status)
474 				return status;
475 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
476 			break;
477 		case NFS4_SET_TO_SERVER_TIME:
478 			iattr->ia_valid |= ATTR_ATIME;
479 			break;
480 		default:
481 			goto xdr_error;
482 		}
483 	}
484 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
485 		READ_BUF(4);
486 		len += 4;
487 		dummy32 = be32_to_cpup(p++);
488 		switch (dummy32) {
489 		case NFS4_SET_TO_CLIENT_TIME:
490 			len += 12;
491 			status = nfsd4_decode_time(argp, &iattr->ia_mtime);
492 			if (status)
493 				return status;
494 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
495 			break;
496 		case NFS4_SET_TO_SERVER_TIME:
497 			iattr->ia_valid |= ATTR_MTIME;
498 			break;
499 		default:
500 			goto xdr_error;
501 		}
502 	}
503 
504 	label->len = 0;
505 	if (IS_ENABLED(CONFIG_NFSD_V4_SECURITY_LABEL) &&
506 	    bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
507 		READ_BUF(4);
508 		len += 4;
509 		dummy32 = be32_to_cpup(p++); /* lfs: we don't use it */
510 		READ_BUF(4);
511 		len += 4;
512 		dummy32 = be32_to_cpup(p++); /* pi: we don't use it either */
513 		READ_BUF(4);
514 		len += 4;
515 		dummy32 = be32_to_cpup(p++);
516 		READ_BUF(dummy32);
517 		if (dummy32 > NFS4_MAXLABELLEN)
518 			return nfserr_badlabel;
519 		len += (XDR_QUADLEN(dummy32) << 2);
520 		READMEM(buf, dummy32);
521 		label->len = dummy32;
522 		label->data = svcxdr_dupstr(argp, buf, dummy32);
523 		if (!label->data)
524 			return nfserr_jukebox;
525 	}
526 	if (bmval[2] & FATTR4_WORD2_MODE_UMASK) {
527 		if (!umask)
528 			goto xdr_error;
529 		READ_BUF(8);
530 		len += 8;
531 		dummy32 = be32_to_cpup(p++);
532 		iattr->ia_mode = dummy32 & (S_IFMT | S_IALLUGO);
533 		dummy32 = be32_to_cpup(p++);
534 		*umask = dummy32 & S_IRWXUGO;
535 		iattr->ia_valid |= ATTR_MODE;
536 	}
537 	if (len != expected_len)
538 		goto xdr_error;
539 
540 	DECODE_TAIL;
541 }
542 
543 static __be32
544 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
545 {
546 	DECODE_HEAD;
547 
548 	READ_BUF(sizeof(stateid_t));
549 	sid->si_generation = be32_to_cpup(p++);
550 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
551 
552 	DECODE_TAIL;
553 }
554 
555 static __be32
556 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
557 {
558 	DECODE_HEAD;
559 
560 	READ_BUF(4);
561 	access->ac_req_access = be32_to_cpup(p++);
562 
563 	DECODE_TAIL;
564 }
565 
566 static __be32 nfsd4_decode_cb_sec(struct nfsd4_compoundargs *argp, struct nfsd4_cb_sec *cbs)
567 {
568 	DECODE_HEAD;
569 	struct user_namespace *userns = nfsd_user_namespace(argp->rqstp);
570 	u32 dummy, uid, gid;
571 	char *machine_name;
572 	int i;
573 	int nr_secflavs;
574 
575 	/* callback_sec_params4 */
576 	READ_BUF(4);
577 	nr_secflavs = be32_to_cpup(p++);
578 	if (nr_secflavs)
579 		cbs->flavor = (u32)(-1);
580 	else
581 		/* Is this legal? Be generous, take it to mean AUTH_NONE: */
582 		cbs->flavor = 0;
583 	for (i = 0; i < nr_secflavs; ++i) {
584 		READ_BUF(4);
585 		dummy = be32_to_cpup(p++);
586 		switch (dummy) {
587 		case RPC_AUTH_NULL:
588 			/* Nothing to read */
589 			if (cbs->flavor == (u32)(-1))
590 				cbs->flavor = RPC_AUTH_NULL;
591 			break;
592 		case RPC_AUTH_UNIX:
593 			READ_BUF(8);
594 			/* stamp */
595 			dummy = be32_to_cpup(p++);
596 
597 			/* machine name */
598 			dummy = be32_to_cpup(p++);
599 			READ_BUF(dummy);
600 			SAVEMEM(machine_name, dummy);
601 
602 			/* uid, gid */
603 			READ_BUF(8);
604 			uid = be32_to_cpup(p++);
605 			gid = be32_to_cpup(p++);
606 
607 			/* more gids */
608 			READ_BUF(4);
609 			dummy = be32_to_cpup(p++);
610 			READ_BUF(dummy * 4);
611 			if (cbs->flavor == (u32)(-1)) {
612 				kuid_t kuid = make_kuid(userns, uid);
613 				kgid_t kgid = make_kgid(userns, gid);
614 				if (uid_valid(kuid) && gid_valid(kgid)) {
615 					cbs->uid = kuid;
616 					cbs->gid = kgid;
617 					cbs->flavor = RPC_AUTH_UNIX;
618 				} else {
619 					dprintk("RPC_AUTH_UNIX with invalid"
620 						"uid or gid ignoring!\n");
621 				}
622 			}
623 			break;
624 		case RPC_AUTH_GSS:
625 			dprintk("RPC_AUTH_GSS callback secflavor "
626 				"not supported!\n");
627 			READ_BUF(8);
628 			/* gcbp_service */
629 			dummy = be32_to_cpup(p++);
630 			/* gcbp_handle_from_server */
631 			dummy = be32_to_cpup(p++);
632 			READ_BUF(dummy);
633 			p += XDR_QUADLEN(dummy);
634 			/* gcbp_handle_from_client */
635 			READ_BUF(4);
636 			dummy = be32_to_cpup(p++);
637 			READ_BUF(dummy);
638 			break;
639 		default:
640 			dprintk("Illegal callback secflavor\n");
641 			return nfserr_inval;
642 		}
643 	}
644 	DECODE_TAIL;
645 }
646 
647 static __be32 nfsd4_decode_backchannel_ctl(struct nfsd4_compoundargs *argp, struct nfsd4_backchannel_ctl *bc)
648 {
649 	DECODE_HEAD;
650 
651 	READ_BUF(4);
652 	bc->bc_cb_program = be32_to_cpup(p++);
653 	nfsd4_decode_cb_sec(argp, &bc->bc_cb_sec);
654 
655 	DECODE_TAIL;
656 }
657 
658 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
659 {
660 	DECODE_HEAD;
661 
662 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
663 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
664 	bcts->dir = be32_to_cpup(p++);
665 	/* XXX: skipping ctsa_use_conn_in_rdma_mode.  Perhaps Tom Tucker
666 	 * could help us figure out we should be using it. */
667 	DECODE_TAIL;
668 }
669 
670 static __be32
671 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
672 {
673 	DECODE_HEAD;
674 
675 	READ_BUF(4);
676 	close->cl_seqid = be32_to_cpup(p++);
677 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
678 
679 	DECODE_TAIL;
680 }
681 
682 
683 static __be32
684 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
685 {
686 	DECODE_HEAD;
687 
688 	READ_BUF(12);
689 	p = xdr_decode_hyper(p, &commit->co_offset);
690 	commit->co_count = be32_to_cpup(p++);
691 
692 	DECODE_TAIL;
693 }
694 
695 static __be32
696 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
697 {
698 	DECODE_HEAD;
699 
700 	READ_BUF(4);
701 	create->cr_type = be32_to_cpup(p++);
702 	switch (create->cr_type) {
703 	case NF4LNK:
704 		READ_BUF(4);
705 		create->cr_datalen = be32_to_cpup(p++);
706 		READ_BUF(create->cr_datalen);
707 		create->cr_data = svcxdr_dupstr(argp, p, create->cr_datalen);
708 		if (!create->cr_data)
709 			return nfserr_jukebox;
710 		break;
711 	case NF4BLK:
712 	case NF4CHR:
713 		READ_BUF(8);
714 		create->cr_specdata1 = be32_to_cpup(p++);
715 		create->cr_specdata2 = be32_to_cpup(p++);
716 		break;
717 	case NF4SOCK:
718 	case NF4FIFO:
719 	case NF4DIR:
720 	default:
721 		break;
722 	}
723 
724 	READ_BUF(4);
725 	create->cr_namelen = be32_to_cpup(p++);
726 	READ_BUF(create->cr_namelen);
727 	SAVEMEM(create->cr_name, create->cr_namelen);
728 	if ((status = check_filename(create->cr_name, create->cr_namelen)))
729 		return status;
730 
731 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
732 				    &create->cr_acl, &create->cr_label,
733 				    &create->cr_umask);
734 	if (status)
735 		goto out;
736 
737 	DECODE_TAIL;
738 }
739 
740 static inline __be32
741 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
742 {
743 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
744 }
745 
746 static inline __be32
747 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
748 {
749 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
750 }
751 
752 static __be32
753 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
754 {
755 	DECODE_HEAD;
756 
757 	READ_BUF(4);
758 	link->li_namelen = be32_to_cpup(p++);
759 	READ_BUF(link->li_namelen);
760 	SAVEMEM(link->li_name, link->li_namelen);
761 	if ((status = check_filename(link->li_name, link->li_namelen)))
762 		return status;
763 
764 	DECODE_TAIL;
765 }
766 
767 static __be32
768 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
769 {
770 	DECODE_HEAD;
771 
772 	/*
773 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
774 	*/
775 	READ_BUF(28);
776 	lock->lk_type = be32_to_cpup(p++);
777 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
778 		goto xdr_error;
779 	lock->lk_reclaim = be32_to_cpup(p++);
780 	p = xdr_decode_hyper(p, &lock->lk_offset);
781 	p = xdr_decode_hyper(p, &lock->lk_length);
782 	lock->lk_is_new = be32_to_cpup(p++);
783 
784 	if (lock->lk_is_new) {
785 		READ_BUF(4);
786 		lock->lk_new_open_seqid = be32_to_cpup(p++);
787 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
788 		if (status)
789 			return status;
790 		READ_BUF(8 + sizeof(clientid_t));
791 		lock->lk_new_lock_seqid = be32_to_cpup(p++);
792 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
793 		lock->lk_new_owner.len = be32_to_cpup(p++);
794 		READ_BUF(lock->lk_new_owner.len);
795 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
796 	} else {
797 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
798 		if (status)
799 			return status;
800 		READ_BUF(4);
801 		lock->lk_old_lock_seqid = be32_to_cpup(p++);
802 	}
803 
804 	DECODE_TAIL;
805 }
806 
807 static __be32
808 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
809 {
810 	DECODE_HEAD;
811 
812 	READ_BUF(32);
813 	lockt->lt_type = be32_to_cpup(p++);
814 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
815 		goto xdr_error;
816 	p = xdr_decode_hyper(p, &lockt->lt_offset);
817 	p = xdr_decode_hyper(p, &lockt->lt_length);
818 	COPYMEM(&lockt->lt_clientid, 8);
819 	lockt->lt_owner.len = be32_to_cpup(p++);
820 	READ_BUF(lockt->lt_owner.len);
821 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
822 
823 	DECODE_TAIL;
824 }
825 
826 static __be32
827 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
828 {
829 	DECODE_HEAD;
830 
831 	READ_BUF(8);
832 	locku->lu_type = be32_to_cpup(p++);
833 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
834 		goto xdr_error;
835 	locku->lu_seqid = be32_to_cpup(p++);
836 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
837 	if (status)
838 		return status;
839 	READ_BUF(16);
840 	p = xdr_decode_hyper(p, &locku->lu_offset);
841 	p = xdr_decode_hyper(p, &locku->lu_length);
842 
843 	DECODE_TAIL;
844 }
845 
846 static __be32
847 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
848 {
849 	DECODE_HEAD;
850 
851 	READ_BUF(4);
852 	lookup->lo_len = be32_to_cpup(p++);
853 	READ_BUF(lookup->lo_len);
854 	SAVEMEM(lookup->lo_name, lookup->lo_len);
855 	if ((status = check_filename(lookup->lo_name, lookup->lo_len)))
856 		return status;
857 
858 	DECODE_TAIL;
859 }
860 
861 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
862 {
863 	__be32 *p;
864 	u32 w;
865 
866 	READ_BUF(4);
867 	w = be32_to_cpup(p++);
868 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
869 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
870 	if (deleg_when)
871 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
872 
873 	switch (w & NFS4_SHARE_ACCESS_MASK) {
874 	case NFS4_SHARE_ACCESS_READ:
875 	case NFS4_SHARE_ACCESS_WRITE:
876 	case NFS4_SHARE_ACCESS_BOTH:
877 		break;
878 	default:
879 		return nfserr_bad_xdr;
880 	}
881 	w &= ~NFS4_SHARE_ACCESS_MASK;
882 	if (!w)
883 		return nfs_ok;
884 	if (!argp->minorversion)
885 		return nfserr_bad_xdr;
886 	switch (w & NFS4_SHARE_WANT_MASK) {
887 	case NFS4_SHARE_WANT_NO_PREFERENCE:
888 	case NFS4_SHARE_WANT_READ_DELEG:
889 	case NFS4_SHARE_WANT_WRITE_DELEG:
890 	case NFS4_SHARE_WANT_ANY_DELEG:
891 	case NFS4_SHARE_WANT_NO_DELEG:
892 	case NFS4_SHARE_WANT_CANCEL:
893 		break;
894 	default:
895 		return nfserr_bad_xdr;
896 	}
897 	w &= ~NFS4_SHARE_WANT_MASK;
898 	if (!w)
899 		return nfs_ok;
900 
901 	if (!deleg_when)	/* open_downgrade */
902 		return nfserr_inval;
903 	switch (w) {
904 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
905 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
906 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
907 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
908 		return nfs_ok;
909 	}
910 xdr_error:
911 	return nfserr_bad_xdr;
912 }
913 
914 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
915 {
916 	__be32 *p;
917 
918 	READ_BUF(4);
919 	*x = be32_to_cpup(p++);
920 	/* Note: unlinke access bits, deny bits may be zero. */
921 	if (*x & ~NFS4_SHARE_DENY_BOTH)
922 		return nfserr_bad_xdr;
923 	return nfs_ok;
924 xdr_error:
925 	return nfserr_bad_xdr;
926 }
927 
928 static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
929 {
930 	__be32 *p;
931 
932 	READ_BUF(4);
933 	o->len = be32_to_cpup(p++);
934 
935 	if (o->len == 0 || o->len > NFS4_OPAQUE_LIMIT)
936 		return nfserr_bad_xdr;
937 
938 	READ_BUF(o->len);
939 	SAVEMEM(o->data, o->len);
940 	return nfs_ok;
941 xdr_error:
942 	return nfserr_bad_xdr;
943 }
944 
945 static __be32
946 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
947 {
948 	DECODE_HEAD;
949 	u32 dummy;
950 
951 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
952 	open->op_iattr.ia_valid = 0;
953 	open->op_openowner = NULL;
954 
955 	open->op_xdr_error = 0;
956 	/* seqid, share_access, share_deny, clientid, ownerlen */
957 	READ_BUF(4);
958 	open->op_seqid = be32_to_cpup(p++);
959 	/* decode, yet ignore deleg_when until supported */
960 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
961 					   &open->op_deleg_want, &dummy);
962 	if (status)
963 		goto xdr_error;
964 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
965 	if (status)
966 		goto xdr_error;
967 	READ_BUF(sizeof(clientid_t));
968 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
969 	status = nfsd4_decode_opaque(argp, &open->op_owner);
970 	if (status)
971 		goto xdr_error;
972 	READ_BUF(4);
973 	open->op_create = be32_to_cpup(p++);
974 	switch (open->op_create) {
975 	case NFS4_OPEN_NOCREATE:
976 		break;
977 	case NFS4_OPEN_CREATE:
978 		READ_BUF(4);
979 		open->op_createmode = be32_to_cpup(p++);
980 		switch (open->op_createmode) {
981 		case NFS4_CREATE_UNCHECKED:
982 		case NFS4_CREATE_GUARDED:
983 			status = nfsd4_decode_fattr(argp, open->op_bmval,
984 				&open->op_iattr, &open->op_acl, &open->op_label,
985 				&open->op_umask);
986 			if (status)
987 				goto out;
988 			break;
989 		case NFS4_CREATE_EXCLUSIVE:
990 			READ_BUF(NFS4_VERIFIER_SIZE);
991 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
992 			break;
993 		case NFS4_CREATE_EXCLUSIVE4_1:
994 			if (argp->minorversion < 1)
995 				goto xdr_error;
996 			READ_BUF(NFS4_VERIFIER_SIZE);
997 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
998 			status = nfsd4_decode_fattr(argp, open->op_bmval,
999 				&open->op_iattr, &open->op_acl, &open->op_label,
1000 				&open->op_umask);
1001 			if (status)
1002 				goto out;
1003 			break;
1004 		default:
1005 			goto xdr_error;
1006 		}
1007 		break;
1008 	default:
1009 		goto xdr_error;
1010 	}
1011 
1012 	/* open_claim */
1013 	READ_BUF(4);
1014 	open->op_claim_type = be32_to_cpup(p++);
1015 	switch (open->op_claim_type) {
1016 	case NFS4_OPEN_CLAIM_NULL:
1017 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
1018 		READ_BUF(4);
1019 		open->op_fname.len = be32_to_cpup(p++);
1020 		READ_BUF(open->op_fname.len);
1021 		SAVEMEM(open->op_fname.data, open->op_fname.len);
1022 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
1023 			return status;
1024 		break;
1025 	case NFS4_OPEN_CLAIM_PREVIOUS:
1026 		READ_BUF(4);
1027 		open->op_delegate_type = be32_to_cpup(p++);
1028 		break;
1029 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
1030 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
1031 		if (status)
1032 			return status;
1033 		READ_BUF(4);
1034 		open->op_fname.len = be32_to_cpup(p++);
1035 		READ_BUF(open->op_fname.len);
1036 		SAVEMEM(open->op_fname.data, open->op_fname.len);
1037 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
1038 			return status;
1039 		break;
1040 	case NFS4_OPEN_CLAIM_FH:
1041 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
1042 		if (argp->minorversion < 1)
1043 			goto xdr_error;
1044 		/* void */
1045 		break;
1046 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
1047 		if (argp->minorversion < 1)
1048 			goto xdr_error;
1049 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
1050 		if (status)
1051 			return status;
1052 		break;
1053 	default:
1054 		goto xdr_error;
1055 	}
1056 
1057 	DECODE_TAIL;
1058 }
1059 
1060 static __be32
1061 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
1062 {
1063 	DECODE_HEAD;
1064 
1065 	if (argp->minorversion >= 1)
1066 		return nfserr_notsupp;
1067 
1068 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
1069 	if (status)
1070 		return status;
1071 	READ_BUF(4);
1072 	open_conf->oc_seqid = be32_to_cpup(p++);
1073 
1074 	DECODE_TAIL;
1075 }
1076 
1077 static __be32
1078 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
1079 {
1080 	DECODE_HEAD;
1081 
1082 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
1083 	if (status)
1084 		return status;
1085 	READ_BUF(4);
1086 	open_down->od_seqid = be32_to_cpup(p++);
1087 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
1088 					   &open_down->od_deleg_want, NULL);
1089 	if (status)
1090 		return status;
1091 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
1092 	if (status)
1093 		return status;
1094 	DECODE_TAIL;
1095 }
1096 
1097 static __be32
1098 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
1099 {
1100 	DECODE_HEAD;
1101 
1102 	READ_BUF(4);
1103 	putfh->pf_fhlen = be32_to_cpup(p++);
1104 	if (putfh->pf_fhlen > NFS4_FHSIZE)
1105 		goto xdr_error;
1106 	READ_BUF(putfh->pf_fhlen);
1107 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
1108 
1109 	DECODE_TAIL;
1110 }
1111 
1112 static __be32
1113 nfsd4_decode_putpubfh(struct nfsd4_compoundargs *argp, void *p)
1114 {
1115 	if (argp->minorversion == 0)
1116 		return nfs_ok;
1117 	return nfserr_notsupp;
1118 }
1119 
1120 static __be32
1121 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
1122 {
1123 	DECODE_HEAD;
1124 
1125 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
1126 	if (status)
1127 		return status;
1128 	READ_BUF(12);
1129 	p = xdr_decode_hyper(p, &read->rd_offset);
1130 	read->rd_length = be32_to_cpup(p++);
1131 
1132 	DECODE_TAIL;
1133 }
1134 
1135 static __be32
1136 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
1137 {
1138 	DECODE_HEAD;
1139 
1140 	READ_BUF(24);
1141 	p = xdr_decode_hyper(p, &readdir->rd_cookie);
1142 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
1143 	readdir->rd_dircount = be32_to_cpup(p++);
1144 	readdir->rd_maxcount = be32_to_cpup(p++);
1145 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
1146 		goto out;
1147 
1148 	DECODE_TAIL;
1149 }
1150 
1151 static __be32
1152 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
1153 {
1154 	DECODE_HEAD;
1155 
1156 	READ_BUF(4);
1157 	remove->rm_namelen = be32_to_cpup(p++);
1158 	READ_BUF(remove->rm_namelen);
1159 	SAVEMEM(remove->rm_name, remove->rm_namelen);
1160 	if ((status = check_filename(remove->rm_name, remove->rm_namelen)))
1161 		return status;
1162 
1163 	DECODE_TAIL;
1164 }
1165 
1166 static __be32
1167 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
1168 {
1169 	DECODE_HEAD;
1170 
1171 	READ_BUF(4);
1172 	rename->rn_snamelen = be32_to_cpup(p++);
1173 	READ_BUF(rename->rn_snamelen);
1174 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1175 	READ_BUF(4);
1176 	rename->rn_tnamelen = be32_to_cpup(p++);
1177 	READ_BUF(rename->rn_tnamelen);
1178 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1179 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1180 		return status;
1181 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1182 		return status;
1183 
1184 	DECODE_TAIL;
1185 }
1186 
1187 static __be32
1188 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1189 {
1190 	DECODE_HEAD;
1191 
1192 	if (argp->minorversion >= 1)
1193 		return nfserr_notsupp;
1194 
1195 	READ_BUF(sizeof(clientid_t));
1196 	COPYMEM(clientid, sizeof(clientid_t));
1197 
1198 	DECODE_TAIL;
1199 }
1200 
1201 static __be32
1202 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1203 		     struct nfsd4_secinfo *secinfo)
1204 {
1205 	DECODE_HEAD;
1206 
1207 	READ_BUF(4);
1208 	secinfo->si_namelen = be32_to_cpup(p++);
1209 	READ_BUF(secinfo->si_namelen);
1210 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1211 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1212 	if (status)
1213 		return status;
1214 	DECODE_TAIL;
1215 }
1216 
1217 static __be32
1218 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1219 		     struct nfsd4_secinfo_no_name *sin)
1220 {
1221 	DECODE_HEAD;
1222 
1223 	READ_BUF(4);
1224 	sin->sin_style = be32_to_cpup(p++);
1225 	DECODE_TAIL;
1226 }
1227 
1228 static __be32
1229 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1230 {
1231 	__be32 status;
1232 
1233 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1234 	if (status)
1235 		return status;
1236 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1237 				  &setattr->sa_acl, &setattr->sa_label, NULL);
1238 }
1239 
1240 static __be32
1241 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1242 {
1243 	DECODE_HEAD;
1244 
1245 	if (argp->minorversion >= 1)
1246 		return nfserr_notsupp;
1247 
1248 	READ_BUF(NFS4_VERIFIER_SIZE);
1249 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1250 
1251 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1252 	if (status)
1253 		return nfserr_bad_xdr;
1254 	READ_BUF(8);
1255 	setclientid->se_callback_prog = be32_to_cpup(p++);
1256 	setclientid->se_callback_netid_len = be32_to_cpup(p++);
1257 	READ_BUF(setclientid->se_callback_netid_len);
1258 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1259 	READ_BUF(4);
1260 	setclientid->se_callback_addr_len = be32_to_cpup(p++);
1261 
1262 	READ_BUF(setclientid->se_callback_addr_len);
1263 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1264 	READ_BUF(4);
1265 	setclientid->se_callback_ident = be32_to_cpup(p++);
1266 
1267 	DECODE_TAIL;
1268 }
1269 
1270 static __be32
1271 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1272 {
1273 	DECODE_HEAD;
1274 
1275 	if (argp->minorversion >= 1)
1276 		return nfserr_notsupp;
1277 
1278 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1279 	COPYMEM(&scd_c->sc_clientid, 8);
1280 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1281 
1282 	DECODE_TAIL;
1283 }
1284 
1285 /* Also used for NVERIFY */
1286 static __be32
1287 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1288 {
1289 	DECODE_HEAD;
1290 
1291 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1292 		goto out;
1293 
1294 	/* For convenience's sake, we compare raw xdr'd attributes in
1295 	 * nfsd4_proc_verify */
1296 
1297 	READ_BUF(4);
1298 	verify->ve_attrlen = be32_to_cpup(p++);
1299 	READ_BUF(verify->ve_attrlen);
1300 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1301 
1302 	DECODE_TAIL;
1303 }
1304 
1305 static __be32
1306 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1307 {
1308 	DECODE_HEAD;
1309 
1310 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1311 	if (status)
1312 		return status;
1313 	READ_BUF(16);
1314 	p = xdr_decode_hyper(p, &write->wr_offset);
1315 	write->wr_stable_how = be32_to_cpup(p++);
1316 	if (write->wr_stable_how > NFS_FILE_SYNC)
1317 		goto xdr_error;
1318 	write->wr_buflen = be32_to_cpup(p++);
1319 
1320 	status = svcxdr_construct_vector(argp, &write->wr_head,
1321 					 &write->wr_pagelist, write->wr_buflen);
1322 	if (status)
1323 		return status;
1324 
1325 	DECODE_TAIL;
1326 }
1327 
1328 static __be32
1329 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1330 {
1331 	DECODE_HEAD;
1332 
1333 	if (argp->minorversion >= 1)
1334 		return nfserr_notsupp;
1335 
1336 	READ_BUF(12);
1337 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1338 	rlockowner->rl_owner.len = be32_to_cpup(p++);
1339 	READ_BUF(rlockowner->rl_owner.len);
1340 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1341 
1342 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1343 		return nfserr_inval;
1344 	DECODE_TAIL;
1345 }
1346 
1347 static __be32
1348 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1349 			 struct nfsd4_exchange_id *exid)
1350 {
1351 	int dummy, tmp;
1352 	DECODE_HEAD;
1353 
1354 	READ_BUF(NFS4_VERIFIER_SIZE);
1355 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1356 
1357 	status = nfsd4_decode_opaque(argp, &exid->clname);
1358 	if (status)
1359 		return nfserr_bad_xdr;
1360 
1361 	READ_BUF(4);
1362 	exid->flags = be32_to_cpup(p++);
1363 
1364 	/* Ignore state_protect4_a */
1365 	READ_BUF(4);
1366 	exid->spa_how = be32_to_cpup(p++);
1367 	switch (exid->spa_how) {
1368 	case SP4_NONE:
1369 		break;
1370 	case SP4_MACH_CRED:
1371 		/* spo_must_enforce */
1372 		status = nfsd4_decode_bitmap(argp,
1373 					exid->spo_must_enforce);
1374 		if (status)
1375 			goto out;
1376 		/* spo_must_allow */
1377 		status = nfsd4_decode_bitmap(argp, exid->spo_must_allow);
1378 		if (status)
1379 			goto out;
1380 		break;
1381 	case SP4_SSV:
1382 		/* ssp_ops */
1383 		READ_BUF(4);
1384 		dummy = be32_to_cpup(p++);
1385 		READ_BUF(dummy * 4);
1386 		p += dummy;
1387 
1388 		READ_BUF(4);
1389 		dummy = be32_to_cpup(p++);
1390 		READ_BUF(dummy * 4);
1391 		p += dummy;
1392 
1393 		/* ssp_hash_algs<> */
1394 		READ_BUF(4);
1395 		tmp = be32_to_cpup(p++);
1396 		while (tmp--) {
1397 			READ_BUF(4);
1398 			dummy = be32_to_cpup(p++);
1399 			READ_BUF(dummy);
1400 			p += XDR_QUADLEN(dummy);
1401 		}
1402 
1403 		/* ssp_encr_algs<> */
1404 		READ_BUF(4);
1405 		tmp = be32_to_cpup(p++);
1406 		while (tmp--) {
1407 			READ_BUF(4);
1408 			dummy = be32_to_cpup(p++);
1409 			READ_BUF(dummy);
1410 			p += XDR_QUADLEN(dummy);
1411 		}
1412 
1413 		/* ignore ssp_window and ssp_num_gss_handles: */
1414 		READ_BUF(8);
1415 		break;
1416 	default:
1417 		goto xdr_error;
1418 	}
1419 
1420 	READ_BUF(4);    /* nfs_impl_id4 array length */
1421 	dummy = be32_to_cpup(p++);
1422 
1423 	if (dummy > 1)
1424 		goto xdr_error;
1425 
1426 	if (dummy == 1) {
1427 		status = nfsd4_decode_opaque(argp, &exid->nii_domain);
1428 		if (status)
1429 			goto xdr_error;
1430 
1431 		/* nii_name */
1432 		status = nfsd4_decode_opaque(argp, &exid->nii_name);
1433 		if (status)
1434 			goto xdr_error;
1435 
1436 		/* nii_date */
1437 		status = nfsd4_decode_time(argp, &exid->nii_time);
1438 		if (status)
1439 			goto xdr_error;
1440 	}
1441 	DECODE_TAIL;
1442 }
1443 
1444 static __be32
1445 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1446 			    struct nfsd4_create_session *sess)
1447 {
1448 	DECODE_HEAD;
1449 
1450 	READ_BUF(16);
1451 	COPYMEM(&sess->clientid, 8);
1452 	sess->seqid = be32_to_cpup(p++);
1453 	sess->flags = be32_to_cpup(p++);
1454 
1455 	/* Fore channel attrs */
1456 	READ_BUF(28);
1457 	p++; /* headerpadsz is always 0 */
1458 	sess->fore_channel.maxreq_sz = be32_to_cpup(p++);
1459 	sess->fore_channel.maxresp_sz = be32_to_cpup(p++);
1460 	sess->fore_channel.maxresp_cached = be32_to_cpup(p++);
1461 	sess->fore_channel.maxops = be32_to_cpup(p++);
1462 	sess->fore_channel.maxreqs = be32_to_cpup(p++);
1463 	sess->fore_channel.nr_rdma_attrs = be32_to_cpup(p++);
1464 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1465 		READ_BUF(4);
1466 		sess->fore_channel.rdma_attrs = be32_to_cpup(p++);
1467 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1468 		dprintk("Too many fore channel attr bitmaps!\n");
1469 		goto xdr_error;
1470 	}
1471 
1472 	/* Back channel attrs */
1473 	READ_BUF(28);
1474 	p++; /* headerpadsz is always 0 */
1475 	sess->back_channel.maxreq_sz = be32_to_cpup(p++);
1476 	sess->back_channel.maxresp_sz = be32_to_cpup(p++);
1477 	sess->back_channel.maxresp_cached = be32_to_cpup(p++);
1478 	sess->back_channel.maxops = be32_to_cpup(p++);
1479 	sess->back_channel.maxreqs = be32_to_cpup(p++);
1480 	sess->back_channel.nr_rdma_attrs = be32_to_cpup(p++);
1481 	if (sess->back_channel.nr_rdma_attrs == 1) {
1482 		READ_BUF(4);
1483 		sess->back_channel.rdma_attrs = be32_to_cpup(p++);
1484 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1485 		dprintk("Too many back channel attr bitmaps!\n");
1486 		goto xdr_error;
1487 	}
1488 
1489 	READ_BUF(4);
1490 	sess->callback_prog = be32_to_cpup(p++);
1491 	nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1492 	DECODE_TAIL;
1493 }
1494 
1495 static __be32
1496 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1497 			     struct nfsd4_destroy_session *destroy_session)
1498 {
1499 	DECODE_HEAD;
1500 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1501 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1502 
1503 	DECODE_TAIL;
1504 }
1505 
1506 static __be32
1507 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1508 			  struct nfsd4_free_stateid *free_stateid)
1509 {
1510 	DECODE_HEAD;
1511 
1512 	READ_BUF(sizeof(stateid_t));
1513 	free_stateid->fr_stateid.si_generation = be32_to_cpup(p++);
1514 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1515 
1516 	DECODE_TAIL;
1517 }
1518 
1519 static __be32
1520 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1521 		      struct nfsd4_sequence *seq)
1522 {
1523 	DECODE_HEAD;
1524 
1525 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1526 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1527 	seq->seqid = be32_to_cpup(p++);
1528 	seq->slotid = be32_to_cpup(p++);
1529 	seq->maxslots = be32_to_cpup(p++);
1530 	seq->cachethis = be32_to_cpup(p++);
1531 
1532 	DECODE_TAIL;
1533 }
1534 
1535 static __be32
1536 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1537 {
1538 	int i;
1539 	__be32 *p, status;
1540 	struct nfsd4_test_stateid_id *stateid;
1541 
1542 	READ_BUF(4);
1543 	test_stateid->ts_num_ids = ntohl(*p++);
1544 
1545 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1546 
1547 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1548 		stateid = svcxdr_tmpalloc(argp, sizeof(*stateid));
1549 		if (!stateid) {
1550 			status = nfserrno(-ENOMEM);
1551 			goto out;
1552 		}
1553 
1554 		INIT_LIST_HEAD(&stateid->ts_id_list);
1555 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1556 
1557 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1558 		if (status)
1559 			goto out;
1560 	}
1561 
1562 	status = 0;
1563 out:
1564 	return status;
1565 xdr_error:
1566 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1567 	status = nfserr_bad_xdr;
1568 	goto out;
1569 }
1570 
1571 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1572 {
1573 	DECODE_HEAD;
1574 
1575 	READ_BUF(8);
1576 	COPYMEM(&dc->clientid, 8);
1577 
1578 	DECODE_TAIL;
1579 }
1580 
1581 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1582 {
1583 	DECODE_HEAD;
1584 
1585 	READ_BUF(4);
1586 	rc->rca_one_fs = be32_to_cpup(p++);
1587 
1588 	DECODE_TAIL;
1589 }
1590 
1591 #ifdef CONFIG_NFSD_PNFS
1592 static __be32
1593 nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp,
1594 		struct nfsd4_getdeviceinfo *gdev)
1595 {
1596 	DECODE_HEAD;
1597 	u32 num, i;
1598 
1599 	READ_BUF(sizeof(struct nfsd4_deviceid) + 3 * 4);
1600 	COPYMEM(&gdev->gd_devid, sizeof(struct nfsd4_deviceid));
1601 	gdev->gd_layout_type = be32_to_cpup(p++);
1602 	gdev->gd_maxcount = be32_to_cpup(p++);
1603 	num = be32_to_cpup(p++);
1604 	if (num) {
1605 		if (num > 1000)
1606 			goto xdr_error;
1607 		READ_BUF(4 * num);
1608 		gdev->gd_notify_types = be32_to_cpup(p++);
1609 		for (i = 1; i < num; i++) {
1610 			if (be32_to_cpup(p++)) {
1611 				status = nfserr_inval;
1612 				goto out;
1613 			}
1614 		}
1615 	}
1616 	DECODE_TAIL;
1617 }
1618 
1619 static __be32
1620 nfsd4_decode_layoutget(struct nfsd4_compoundargs *argp,
1621 		struct nfsd4_layoutget *lgp)
1622 {
1623 	DECODE_HEAD;
1624 
1625 	READ_BUF(36);
1626 	lgp->lg_signal = be32_to_cpup(p++);
1627 	lgp->lg_layout_type = be32_to_cpup(p++);
1628 	lgp->lg_seg.iomode = be32_to_cpup(p++);
1629 	p = xdr_decode_hyper(p, &lgp->lg_seg.offset);
1630 	p = xdr_decode_hyper(p, &lgp->lg_seg.length);
1631 	p = xdr_decode_hyper(p, &lgp->lg_minlength);
1632 
1633 	status = nfsd4_decode_stateid(argp, &lgp->lg_sid);
1634 	if (status)
1635 		return status;
1636 
1637 	READ_BUF(4);
1638 	lgp->lg_maxcount = be32_to_cpup(p++);
1639 
1640 	DECODE_TAIL;
1641 }
1642 
1643 static __be32
1644 nfsd4_decode_layoutcommit(struct nfsd4_compoundargs *argp,
1645 		struct nfsd4_layoutcommit *lcp)
1646 {
1647 	DECODE_HEAD;
1648 	u32 timechange;
1649 
1650 	READ_BUF(20);
1651 	p = xdr_decode_hyper(p, &lcp->lc_seg.offset);
1652 	p = xdr_decode_hyper(p, &lcp->lc_seg.length);
1653 	lcp->lc_reclaim = be32_to_cpup(p++);
1654 
1655 	status = nfsd4_decode_stateid(argp, &lcp->lc_sid);
1656 	if (status)
1657 		return status;
1658 
1659 	READ_BUF(4);
1660 	lcp->lc_newoffset = be32_to_cpup(p++);
1661 	if (lcp->lc_newoffset) {
1662 		READ_BUF(8);
1663 		p = xdr_decode_hyper(p, &lcp->lc_last_wr);
1664 	} else
1665 		lcp->lc_last_wr = 0;
1666 	READ_BUF(4);
1667 	timechange = be32_to_cpup(p++);
1668 	if (timechange) {
1669 		status = nfsd4_decode_time(argp, &lcp->lc_mtime);
1670 		if (status)
1671 			return status;
1672 	} else {
1673 		lcp->lc_mtime.tv_nsec = UTIME_NOW;
1674 	}
1675 	READ_BUF(8);
1676 	lcp->lc_layout_type = be32_to_cpup(p++);
1677 
1678 	/*
1679 	 * Save the layout update in XDR format and let the layout driver deal
1680 	 * with it later.
1681 	 */
1682 	lcp->lc_up_len = be32_to_cpup(p++);
1683 	if (lcp->lc_up_len > 0) {
1684 		READ_BUF(lcp->lc_up_len);
1685 		READMEM(lcp->lc_up_layout, lcp->lc_up_len);
1686 	}
1687 
1688 	DECODE_TAIL;
1689 }
1690 
1691 static __be32
1692 nfsd4_decode_layoutreturn(struct nfsd4_compoundargs *argp,
1693 		struct nfsd4_layoutreturn *lrp)
1694 {
1695 	DECODE_HEAD;
1696 
1697 	READ_BUF(16);
1698 	lrp->lr_reclaim = be32_to_cpup(p++);
1699 	lrp->lr_layout_type = be32_to_cpup(p++);
1700 	lrp->lr_seg.iomode = be32_to_cpup(p++);
1701 	lrp->lr_return_type = be32_to_cpup(p++);
1702 	if (lrp->lr_return_type == RETURN_FILE) {
1703 		READ_BUF(16);
1704 		p = xdr_decode_hyper(p, &lrp->lr_seg.offset);
1705 		p = xdr_decode_hyper(p, &lrp->lr_seg.length);
1706 
1707 		status = nfsd4_decode_stateid(argp, &lrp->lr_sid);
1708 		if (status)
1709 			return status;
1710 
1711 		READ_BUF(4);
1712 		lrp->lrf_body_len = be32_to_cpup(p++);
1713 		if (lrp->lrf_body_len > 0) {
1714 			READ_BUF(lrp->lrf_body_len);
1715 			READMEM(lrp->lrf_body, lrp->lrf_body_len);
1716 		}
1717 	} else {
1718 		lrp->lr_seg.offset = 0;
1719 		lrp->lr_seg.length = NFS4_MAX_UINT64;
1720 	}
1721 
1722 	DECODE_TAIL;
1723 }
1724 #endif /* CONFIG_NFSD_PNFS */
1725 
1726 static __be32
1727 nfsd4_decode_fallocate(struct nfsd4_compoundargs *argp,
1728 		       struct nfsd4_fallocate *fallocate)
1729 {
1730 	DECODE_HEAD;
1731 
1732 	status = nfsd4_decode_stateid(argp, &fallocate->falloc_stateid);
1733 	if (status)
1734 		return status;
1735 
1736 	READ_BUF(16);
1737 	p = xdr_decode_hyper(p, &fallocate->falloc_offset);
1738 	xdr_decode_hyper(p, &fallocate->falloc_length);
1739 
1740 	DECODE_TAIL;
1741 }
1742 
1743 static __be32
1744 nfsd4_decode_clone(struct nfsd4_compoundargs *argp, struct nfsd4_clone *clone)
1745 {
1746 	DECODE_HEAD;
1747 
1748 	status = nfsd4_decode_stateid(argp, &clone->cl_src_stateid);
1749 	if (status)
1750 		return status;
1751 	status = nfsd4_decode_stateid(argp, &clone->cl_dst_stateid);
1752 	if (status)
1753 		return status;
1754 
1755 	READ_BUF(8 + 8 + 8);
1756 	p = xdr_decode_hyper(p, &clone->cl_src_pos);
1757 	p = xdr_decode_hyper(p, &clone->cl_dst_pos);
1758 	p = xdr_decode_hyper(p, &clone->cl_count);
1759 	DECODE_TAIL;
1760 }
1761 
1762 static __be32 nfsd4_decode_nl4_server(struct nfsd4_compoundargs *argp,
1763 				      struct nl4_server *ns)
1764 {
1765 	DECODE_HEAD;
1766 	struct nfs42_netaddr *naddr;
1767 
1768 	READ_BUF(4);
1769 	ns->nl4_type = be32_to_cpup(p++);
1770 
1771 	/* currently support for 1 inter-server source server */
1772 	switch (ns->nl4_type) {
1773 	case NL4_NETADDR:
1774 		naddr = &ns->u.nl4_addr;
1775 
1776 		READ_BUF(4);
1777 		naddr->netid_len = be32_to_cpup(p++);
1778 		if (naddr->netid_len > RPCBIND_MAXNETIDLEN)
1779 			goto xdr_error;
1780 
1781 		READ_BUF(naddr->netid_len + 4); /* 4 for uaddr len */
1782 		COPYMEM(naddr->netid, naddr->netid_len);
1783 
1784 		naddr->addr_len = be32_to_cpup(p++);
1785 		if (naddr->addr_len > RPCBIND_MAXUADDRLEN)
1786 			goto xdr_error;
1787 
1788 		READ_BUF(naddr->addr_len);
1789 		COPYMEM(naddr->addr, naddr->addr_len);
1790 		break;
1791 	default:
1792 		goto xdr_error;
1793 	}
1794 	DECODE_TAIL;
1795 }
1796 
1797 static __be32
1798 nfsd4_decode_copy(struct nfsd4_compoundargs *argp, struct nfsd4_copy *copy)
1799 {
1800 	DECODE_HEAD;
1801 	struct nl4_server *ns_dummy;
1802 	int i, count;
1803 
1804 	status = nfsd4_decode_stateid(argp, &copy->cp_src_stateid);
1805 	if (status)
1806 		return status;
1807 	status = nfsd4_decode_stateid(argp, &copy->cp_dst_stateid);
1808 	if (status)
1809 		return status;
1810 
1811 	READ_BUF(8 + 8 + 8 + 4 + 4 + 4);
1812 	p = xdr_decode_hyper(p, &copy->cp_src_pos);
1813 	p = xdr_decode_hyper(p, &copy->cp_dst_pos);
1814 	p = xdr_decode_hyper(p, &copy->cp_count);
1815 	p++; /* ca_consecutive: we always do consecutive copies */
1816 	copy->cp_synchronous = be32_to_cpup(p++);
1817 
1818 	count = be32_to_cpup(p++);
1819 
1820 	copy->cp_intra = false;
1821 	if (count == 0) { /* intra-server copy */
1822 		copy->cp_intra = true;
1823 		goto intra;
1824 	}
1825 
1826 	/* decode all the supplied server addresses but use first */
1827 	status = nfsd4_decode_nl4_server(argp, &copy->cp_src);
1828 	if (status)
1829 		return status;
1830 
1831 	ns_dummy = kmalloc(sizeof(struct nl4_server), GFP_KERNEL);
1832 	if (ns_dummy == NULL)
1833 		return nfserrno(-ENOMEM);
1834 	for (i = 0; i < count - 1; i++) {
1835 		status = nfsd4_decode_nl4_server(argp, ns_dummy);
1836 		if (status) {
1837 			kfree(ns_dummy);
1838 			return status;
1839 		}
1840 	}
1841 	kfree(ns_dummy);
1842 intra:
1843 
1844 	DECODE_TAIL;
1845 }
1846 
1847 static __be32
1848 nfsd4_decode_offload_status(struct nfsd4_compoundargs *argp,
1849 			    struct nfsd4_offload_status *os)
1850 {
1851 	return nfsd4_decode_stateid(argp, &os->stateid);
1852 }
1853 
1854 static __be32
1855 nfsd4_decode_copy_notify(struct nfsd4_compoundargs *argp,
1856 			 struct nfsd4_copy_notify *cn)
1857 {
1858 	__be32 status;
1859 
1860 	status = nfsd4_decode_stateid(argp, &cn->cpn_src_stateid);
1861 	if (status)
1862 		return status;
1863 	return nfsd4_decode_nl4_server(argp, &cn->cpn_dst);
1864 }
1865 
1866 static __be32
1867 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
1868 {
1869 	DECODE_HEAD;
1870 
1871 	status = nfsd4_decode_stateid(argp, &seek->seek_stateid);
1872 	if (status)
1873 		return status;
1874 
1875 	READ_BUF(8 + 4);
1876 	p = xdr_decode_hyper(p, &seek->seek_offset);
1877 	seek->seek_whence = be32_to_cpup(p);
1878 
1879 	DECODE_TAIL;
1880 }
1881 
1882 /*
1883  * XDR data that is more than PAGE_SIZE in size is normally part of a
1884  * read or write. However, the size of extended attributes is limited
1885  * by the maximum request size, and then further limited by the underlying
1886  * filesystem limits. This can exceed PAGE_SIZE (currently, XATTR_SIZE_MAX
1887  * is 64k). Since there is no kvec- or page-based interface to xattrs,
1888  * and we're not dealing with contiguous pages, we need to do some copying.
1889  */
1890 
1891 /*
1892  * Decode data into buffer. Uses head and pages constructed by
1893  * svcxdr_construct_vector.
1894  */
1895 static __be32
1896 nfsd4_vbuf_from_vector(struct nfsd4_compoundargs *argp, struct kvec *head,
1897 		       struct page **pages, char **bufp, u32 buflen)
1898 {
1899 	char *tmp, *dp;
1900 	u32 len;
1901 
1902 	if (buflen <= head->iov_len) {
1903 		/*
1904 		 * We're in luck, the head has enough space. Just return
1905 		 * the head, no need for copying.
1906 		 */
1907 		*bufp = head->iov_base;
1908 		return 0;
1909 	}
1910 
1911 	tmp = svcxdr_tmpalloc(argp, buflen);
1912 	if (tmp == NULL)
1913 		return nfserr_jukebox;
1914 
1915 	dp = tmp;
1916 	memcpy(dp, head->iov_base, head->iov_len);
1917 	buflen -= head->iov_len;
1918 	dp += head->iov_len;
1919 
1920 	while (buflen > 0) {
1921 		len = min_t(u32, buflen, PAGE_SIZE);
1922 		memcpy(dp, page_address(*pages), len);
1923 
1924 		buflen -= len;
1925 		dp += len;
1926 		pages++;
1927 	}
1928 
1929 	*bufp = tmp;
1930 	return 0;
1931 }
1932 
1933 /*
1934  * Get a user extended attribute name from the XDR buffer.
1935  * It will not have the "user." prefix, so prepend it.
1936  * Lastly, check for nul characters in the name.
1937  */
1938 static __be32
1939 nfsd4_decode_xattr_name(struct nfsd4_compoundargs *argp, char **namep)
1940 {
1941 	DECODE_HEAD;
1942 	char *name, *sp, *dp;
1943 	u32 namelen, cnt;
1944 
1945 	READ_BUF(4);
1946 	namelen = be32_to_cpup(p++);
1947 
1948 	if (namelen > (XATTR_NAME_MAX - XATTR_USER_PREFIX_LEN))
1949 		return nfserr_nametoolong;
1950 
1951 	if (namelen == 0)
1952 		goto xdr_error;
1953 
1954 	READ_BUF(namelen);
1955 
1956 	name = svcxdr_tmpalloc(argp, namelen + XATTR_USER_PREFIX_LEN + 1);
1957 	if (!name)
1958 		return nfserr_jukebox;
1959 
1960 	memcpy(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
1961 
1962 	/*
1963 	 * Copy the extended attribute name over while checking for 0
1964 	 * characters.
1965 	 */
1966 	sp = (char *)p;
1967 	dp = name + XATTR_USER_PREFIX_LEN;
1968 	cnt = namelen;
1969 
1970 	while (cnt-- > 0) {
1971 		if (*sp == '\0')
1972 			goto xdr_error;
1973 		*dp++ = *sp++;
1974 	}
1975 	*dp = '\0';
1976 
1977 	*namep = name;
1978 
1979 	DECODE_TAIL;
1980 }
1981 
1982 /*
1983  * A GETXATTR op request comes without a length specifier. We just set the
1984  * maximum length for the reply based on XATTR_SIZE_MAX and the maximum
1985  * channel reply size. nfsd_getxattr will probe the length of the xattr,
1986  * check it against getxa_len, and allocate + return the value.
1987  */
1988 static __be32
1989 nfsd4_decode_getxattr(struct nfsd4_compoundargs *argp,
1990 		      struct nfsd4_getxattr *getxattr)
1991 {
1992 	__be32 status;
1993 	u32 maxcount;
1994 
1995 	status = nfsd4_decode_xattr_name(argp, &getxattr->getxa_name);
1996 	if (status)
1997 		return status;
1998 
1999 	maxcount = svc_max_payload(argp->rqstp);
2000 	maxcount = min_t(u32, XATTR_SIZE_MAX, maxcount);
2001 
2002 	getxattr->getxa_len = maxcount;
2003 
2004 	return status;
2005 }
2006 
2007 static __be32
2008 nfsd4_decode_setxattr(struct nfsd4_compoundargs *argp,
2009 		      struct nfsd4_setxattr *setxattr)
2010 {
2011 	DECODE_HEAD;
2012 	u32 flags, maxcount, size;
2013 	struct kvec head;
2014 	struct page **pagelist;
2015 
2016 	READ_BUF(4);
2017 	flags = be32_to_cpup(p++);
2018 
2019 	if (flags > SETXATTR4_REPLACE)
2020 		return nfserr_inval;
2021 	setxattr->setxa_flags = flags;
2022 
2023 	status = nfsd4_decode_xattr_name(argp, &setxattr->setxa_name);
2024 	if (status)
2025 		return status;
2026 
2027 	maxcount = svc_max_payload(argp->rqstp);
2028 	maxcount = min_t(u32, XATTR_SIZE_MAX, maxcount);
2029 
2030 	READ_BUF(4);
2031 	size = be32_to_cpup(p++);
2032 	if (size > maxcount)
2033 		return nfserr_xattr2big;
2034 
2035 	setxattr->setxa_len = size;
2036 	if (size > 0) {
2037 		status = svcxdr_construct_vector(argp, &head, &pagelist, size);
2038 		if (status)
2039 			return status;
2040 
2041 		status = nfsd4_vbuf_from_vector(argp, &head, pagelist,
2042 		    &setxattr->setxa_buf, size);
2043 	}
2044 
2045 	DECODE_TAIL;
2046 }
2047 
2048 static __be32
2049 nfsd4_decode_listxattrs(struct nfsd4_compoundargs *argp,
2050 			struct nfsd4_listxattrs *listxattrs)
2051 {
2052 	DECODE_HEAD;
2053 	u32 maxcount;
2054 
2055 	READ_BUF(12);
2056 	p = xdr_decode_hyper(p, &listxattrs->lsxa_cookie);
2057 
2058 	/*
2059 	 * If the cookie  is too large to have even one user.x attribute
2060 	 * plus trailing '\0' left in a maximum size buffer, it's invalid.
2061 	 */
2062 	if (listxattrs->lsxa_cookie >=
2063 	    (XATTR_LIST_MAX / (XATTR_USER_PREFIX_LEN + 2)))
2064 		return nfserr_badcookie;
2065 
2066 	maxcount = be32_to_cpup(p++);
2067 	if (maxcount < 8)
2068 		/* Always need at least 2 words (length and one character) */
2069 		return nfserr_inval;
2070 
2071 	maxcount = min(maxcount, svc_max_payload(argp->rqstp));
2072 	listxattrs->lsxa_maxcount = maxcount;
2073 
2074 	DECODE_TAIL;
2075 }
2076 
2077 static __be32
2078 nfsd4_decode_removexattr(struct nfsd4_compoundargs *argp,
2079 			 struct nfsd4_removexattr *removexattr)
2080 {
2081 	return nfsd4_decode_xattr_name(argp, &removexattr->rmxa_name);
2082 }
2083 
2084 static __be32
2085 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
2086 {
2087 	return nfs_ok;
2088 }
2089 
2090 static __be32
2091 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
2092 {
2093 	return nfserr_notsupp;
2094 }
2095 
2096 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
2097 
2098 static const nfsd4_dec nfsd4_dec_ops[] = {
2099 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
2100 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
2101 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
2102 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
2103 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
2104 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
2105 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
2106 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
2107 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
2108 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
2109 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
2110 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
2111 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
2112 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
2113 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
2114 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
2115 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
2116 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
2117 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
2118 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
2119 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_putpubfh,
2120 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
2121 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
2122 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
2123 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
2124 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
2125 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
2126 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
2127 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
2128 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
2129 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
2130 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
2131 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
2132 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
2133 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
2134 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
2135 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
2136 
2137 	/* new operations for NFSv4.1 */
2138 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_backchannel_ctl,
2139 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
2140 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
2141 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
2142 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
2143 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
2144 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
2145 #ifdef CONFIG_NFSD_PNFS
2146 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_getdeviceinfo,
2147 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
2148 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_layoutcommit,
2149 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_layoutget,
2150 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_layoutreturn,
2151 #else
2152 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
2153 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
2154 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
2155 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
2156 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
2157 #endif
2158 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
2159 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
2160 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
2161 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
2162 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
2163 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
2164 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
2165 
2166 	/* new operations for NFSv4.2 */
2167 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
2168 	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_copy,
2169 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_copy_notify,
2170 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
2171 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
2172 	[OP_LAYOUTERROR]	= (nfsd4_dec)nfsd4_decode_notsupp,
2173 	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,
2174 	[OP_OFFLOAD_CANCEL]	= (nfsd4_dec)nfsd4_decode_offload_status,
2175 	[OP_OFFLOAD_STATUS]	= (nfsd4_dec)nfsd4_decode_offload_status,
2176 	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_read,
2177 	[OP_SEEK]		= (nfsd4_dec)nfsd4_decode_seek,
2178 	[OP_WRITE_SAME]		= (nfsd4_dec)nfsd4_decode_notsupp,
2179 	[OP_CLONE]		= (nfsd4_dec)nfsd4_decode_clone,
2180 	/* RFC 8276 extended atributes operations */
2181 	[OP_GETXATTR]		= (nfsd4_dec)nfsd4_decode_getxattr,
2182 	[OP_SETXATTR]		= (nfsd4_dec)nfsd4_decode_setxattr,
2183 	[OP_LISTXATTRS]		= (nfsd4_dec)nfsd4_decode_listxattrs,
2184 	[OP_REMOVEXATTR]	= (nfsd4_dec)nfsd4_decode_removexattr,
2185 };
2186 
2187 static inline bool
2188 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
2189 {
2190 	if (op->opnum < FIRST_NFS4_OP)
2191 		return false;
2192 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
2193 		return false;
2194 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
2195 		return false;
2196 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
2197 		return false;
2198 	return true;
2199 }
2200 
2201 static __be32
2202 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
2203 {
2204 	DECODE_HEAD;
2205 	struct nfsd4_op *op;
2206 	bool cachethis = false;
2207 	int auth_slack= argp->rqstp->rq_auth_slack;
2208 	int max_reply = auth_slack + 8; /* opcnt, status */
2209 	int readcount = 0;
2210 	int readbytes = 0;
2211 	int i;
2212 
2213 	READ_BUF(4);
2214 	argp->taglen = be32_to_cpup(p++);
2215 	READ_BUF(argp->taglen);
2216 	SAVEMEM(argp->tag, argp->taglen);
2217 	READ_BUF(8);
2218 	argp->minorversion = be32_to_cpup(p++);
2219 	argp->opcnt = be32_to_cpup(p++);
2220 	max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
2221 
2222 	if (argp->taglen > NFSD4_MAX_TAGLEN)
2223 		goto xdr_error;
2224 	/*
2225 	 * NFS4ERR_RESOURCE is a more helpful error than GARBAGE_ARGS
2226 	 * here, so we return success at the xdr level so that
2227 	 * nfsd4_proc can handle this is an NFS-level error.
2228 	 */
2229 	if (argp->opcnt > NFSD_MAX_OPS_PER_COMPOUND)
2230 		return 0;
2231 
2232 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
2233 		argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
2234 		if (!argp->ops) {
2235 			argp->ops = argp->iops;
2236 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
2237 			goto xdr_error;
2238 		}
2239 	}
2240 
2241 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
2242 		argp->opcnt = 0;
2243 
2244 	for (i = 0; i < argp->opcnt; i++) {
2245 		op = &argp->ops[i];
2246 		op->replay = NULL;
2247 
2248 		READ_BUF(4);
2249 		op->opnum = be32_to_cpup(p++);
2250 
2251 		if (nfsd4_opnum_in_range(argp, op))
2252 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
2253 		else {
2254 			op->opnum = OP_ILLEGAL;
2255 			op->status = nfserr_op_illegal;
2256 		}
2257 		op->opdesc = OPDESC(op);
2258 		/*
2259 		 * We'll try to cache the result in the DRC if any one
2260 		 * op in the compound wants to be cached:
2261 		 */
2262 		cachethis |= nfsd4_cache_this_op(op);
2263 
2264 		if (op->opnum == OP_READ || op->opnum == OP_READ_PLUS) {
2265 			readcount++;
2266 			readbytes += nfsd4_max_reply(argp->rqstp, op);
2267 		} else
2268 			max_reply += nfsd4_max_reply(argp->rqstp, op);
2269 		/*
2270 		 * OP_LOCK and OP_LOCKT may return a conflicting lock.
2271 		 * (Special case because it will just skip encoding this
2272 		 * if it runs out of xdr buffer space, and it is the only
2273 		 * operation that behaves this way.)
2274 		 */
2275 		if (op->opnum == OP_LOCK || op->opnum == OP_LOCKT)
2276 			max_reply += NFS4_OPAQUE_LIMIT;
2277 
2278 		if (op->status) {
2279 			argp->opcnt = i+1;
2280 			break;
2281 		}
2282 	}
2283 	/* Sessions make the DRC unnecessary: */
2284 	if (argp->minorversion)
2285 		cachethis = false;
2286 	svc_reserve(argp->rqstp, max_reply + readbytes);
2287 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
2288 
2289 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
2290 		clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
2291 
2292 	DECODE_TAIL;
2293 }
2294 
2295 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode,
2296 			     struct svc_export *exp)
2297 {
2298 	if (exp->ex_flags & NFSEXP_V4ROOT) {
2299 		*p++ = cpu_to_be32(convert_to_wallclock(exp->cd->flush_time));
2300 		*p++ = 0;
2301 	} else if (IS_I_VERSION(inode)) {
2302 		p = xdr_encode_hyper(p, nfsd4_change_attribute(stat, inode));
2303 	} else {
2304 		*p++ = cpu_to_be32(stat->ctime.tv_sec);
2305 		*p++ = cpu_to_be32(stat->ctime.tv_nsec);
2306 	}
2307 	return p;
2308 }
2309 
2310 /*
2311  * ctime (in NFSv4, time_metadata) is not writeable, and the client
2312  * doesn't really care what resolution could theoretically be stored by
2313  * the filesystem.
2314  *
2315  * The client cares how close together changes can be while still
2316  * guaranteeing ctime changes.  For most filesystems (which have
2317  * timestamps with nanosecond fields) that is limited by the resolution
2318  * of the time returned from current_time() (which I'm assuming to be
2319  * 1/HZ).
2320  */
2321 static __be32 *encode_time_delta(__be32 *p, struct inode *inode)
2322 {
2323 	struct timespec64 ts;
2324 	u32 ns;
2325 
2326 	ns = max_t(u32, NSEC_PER_SEC/HZ, inode->i_sb->s_time_gran);
2327 	ts = ns_to_timespec64(ns);
2328 
2329 	p = xdr_encode_hyper(p, ts.tv_sec);
2330 	*p++ = cpu_to_be32(ts.tv_nsec);
2331 
2332 	return p;
2333 }
2334 
2335 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
2336 {
2337 	*p++ = cpu_to_be32(c->atomic);
2338 	if (c->change_supported) {
2339 		p = xdr_encode_hyper(p, c->before_change);
2340 		p = xdr_encode_hyper(p, c->after_change);
2341 	} else {
2342 		*p++ = cpu_to_be32(c->before_ctime_sec);
2343 		*p++ = cpu_to_be32(c->before_ctime_nsec);
2344 		*p++ = cpu_to_be32(c->after_ctime_sec);
2345 		*p++ = cpu_to_be32(c->after_ctime_nsec);
2346 	}
2347 	return p;
2348 }
2349 
2350 /* Encode as an array of strings the string given with components
2351  * separated @sep, escaped with esc_enter and esc_exit.
2352  */
2353 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
2354 					  char *components, char esc_enter,
2355 					  char esc_exit)
2356 {
2357 	__be32 *p;
2358 	__be32 pathlen;
2359 	int pathlen_offset;
2360 	int strlen, count=0;
2361 	char *str, *end, *next;
2362 
2363 	dprintk("nfsd4_encode_components(%s)\n", components);
2364 
2365 	pathlen_offset = xdr->buf->len;
2366 	p = xdr_reserve_space(xdr, 4);
2367 	if (!p)
2368 		return nfserr_resource;
2369 	p++; /* We will fill this in with @count later */
2370 
2371 	end = str = components;
2372 	while (*end) {
2373 		bool found_esc = false;
2374 
2375 		/* try to parse as esc_start, ..., esc_end, sep */
2376 		if (*str == esc_enter) {
2377 			for (; *end && (*end != esc_exit); end++)
2378 				/* find esc_exit or end of string */;
2379 			next = end + 1;
2380 			if (*end && (!*next || *next == sep)) {
2381 				str++;
2382 				found_esc = true;
2383 			}
2384 		}
2385 
2386 		if (!found_esc)
2387 			for (; *end && (*end != sep); end++)
2388 				/* find sep or end of string */;
2389 
2390 		strlen = end - str;
2391 		if (strlen) {
2392 			p = xdr_reserve_space(xdr, strlen + 4);
2393 			if (!p)
2394 				return nfserr_resource;
2395 			p = xdr_encode_opaque(p, str, strlen);
2396 			count++;
2397 		}
2398 		else
2399 			end++;
2400 		if (found_esc)
2401 			end = next;
2402 
2403 		str = end;
2404 	}
2405 	pathlen = htonl(count);
2406 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
2407 	return 0;
2408 }
2409 
2410 /* Encode as an array of strings the string given with components
2411  * separated @sep.
2412  */
2413 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
2414 				      char *components)
2415 {
2416 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
2417 }
2418 
2419 /*
2420  * encode a location element of a fs_locations structure
2421  */
2422 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
2423 					struct nfsd4_fs_location *location)
2424 {
2425 	__be32 status;
2426 
2427 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
2428 						'[', ']');
2429 	if (status)
2430 		return status;
2431 	status = nfsd4_encode_components(xdr, '/', location->path);
2432 	if (status)
2433 		return status;
2434 	return 0;
2435 }
2436 
2437 /*
2438  * Encode a path in RFC3530 'pathname4' format
2439  */
2440 static __be32 nfsd4_encode_path(struct xdr_stream *xdr,
2441 				const struct path *root,
2442 				const struct path *path)
2443 {
2444 	struct path cur = *path;
2445 	__be32 *p;
2446 	struct dentry **components = NULL;
2447 	unsigned int ncomponents = 0;
2448 	__be32 err = nfserr_jukebox;
2449 
2450 	dprintk("nfsd4_encode_components(");
2451 
2452 	path_get(&cur);
2453 	/* First walk the path up to the nfsd root, and store the
2454 	 * dentries/path components in an array.
2455 	 */
2456 	for (;;) {
2457 		if (path_equal(&cur, root))
2458 			break;
2459 		if (cur.dentry == cur.mnt->mnt_root) {
2460 			if (follow_up(&cur))
2461 				continue;
2462 			goto out_free;
2463 		}
2464 		if ((ncomponents & 15) == 0) {
2465 			struct dentry **new;
2466 			new = krealloc(components,
2467 					sizeof(*new) * (ncomponents + 16),
2468 					GFP_KERNEL);
2469 			if (!new)
2470 				goto out_free;
2471 			components = new;
2472 		}
2473 		components[ncomponents++] = cur.dentry;
2474 		cur.dentry = dget_parent(cur.dentry);
2475 	}
2476 	err = nfserr_resource;
2477 	p = xdr_reserve_space(xdr, 4);
2478 	if (!p)
2479 		goto out_free;
2480 	*p++ = cpu_to_be32(ncomponents);
2481 
2482 	while (ncomponents) {
2483 		struct dentry *dentry = components[ncomponents - 1];
2484 		unsigned int len;
2485 
2486 		spin_lock(&dentry->d_lock);
2487 		len = dentry->d_name.len;
2488 		p = xdr_reserve_space(xdr, len + 4);
2489 		if (!p) {
2490 			spin_unlock(&dentry->d_lock);
2491 			goto out_free;
2492 		}
2493 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
2494 		dprintk("/%pd", dentry);
2495 		spin_unlock(&dentry->d_lock);
2496 		dput(dentry);
2497 		ncomponents--;
2498 	}
2499 
2500 	err = 0;
2501 out_free:
2502 	dprintk(")\n");
2503 	while (ncomponents)
2504 		dput(components[--ncomponents]);
2505 	kfree(components);
2506 	path_put(&cur);
2507 	return err;
2508 }
2509 
2510 static __be32 nfsd4_encode_fsloc_fsroot(struct xdr_stream *xdr,
2511 			struct svc_rqst *rqstp, const struct path *path)
2512 {
2513 	struct svc_export *exp_ps;
2514 	__be32 res;
2515 
2516 	exp_ps = rqst_find_fsidzero_export(rqstp);
2517 	if (IS_ERR(exp_ps))
2518 		return nfserrno(PTR_ERR(exp_ps));
2519 	res = nfsd4_encode_path(xdr, &exp_ps->ex_path, path);
2520 	exp_put(exp_ps);
2521 	return res;
2522 }
2523 
2524 /*
2525  *  encode a fs_locations structure
2526  */
2527 static __be32 nfsd4_encode_fs_locations(struct xdr_stream *xdr,
2528 			struct svc_rqst *rqstp, struct svc_export *exp)
2529 {
2530 	__be32 status;
2531 	int i;
2532 	__be32 *p;
2533 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
2534 
2535 	status = nfsd4_encode_fsloc_fsroot(xdr, rqstp, &exp->ex_path);
2536 	if (status)
2537 		return status;
2538 	p = xdr_reserve_space(xdr, 4);
2539 	if (!p)
2540 		return nfserr_resource;
2541 	*p++ = cpu_to_be32(fslocs->locations_count);
2542 	for (i=0; i<fslocs->locations_count; i++) {
2543 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
2544 		if (status)
2545 			return status;
2546 	}
2547 	return 0;
2548 }
2549 
2550 static u32 nfs4_file_type(umode_t mode)
2551 {
2552 	switch (mode & S_IFMT) {
2553 	case S_IFIFO:	return NF4FIFO;
2554 	case S_IFCHR:	return NF4CHR;
2555 	case S_IFDIR:	return NF4DIR;
2556 	case S_IFBLK:	return NF4BLK;
2557 	case S_IFLNK:	return NF4LNK;
2558 	case S_IFREG:	return NF4REG;
2559 	case S_IFSOCK:	return NF4SOCK;
2560 	default:	return NF4BAD;
2561 	};
2562 }
2563 
2564 static inline __be32
2565 nfsd4_encode_aclname(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2566 		     struct nfs4_ace *ace)
2567 {
2568 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
2569 		return nfs4_acl_write_who(xdr, ace->whotype);
2570 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
2571 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
2572 	else
2573 		return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
2574 }
2575 
2576 static inline __be32
2577 nfsd4_encode_layout_types(struct xdr_stream *xdr, u32 layout_types)
2578 {
2579 	__be32		*p;
2580 	unsigned long	i = hweight_long(layout_types);
2581 
2582 	p = xdr_reserve_space(xdr, 4 + 4 * i);
2583 	if (!p)
2584 		return nfserr_resource;
2585 
2586 	*p++ = cpu_to_be32(i);
2587 
2588 	for (i = LAYOUT_NFSV4_1_FILES; i < LAYOUT_TYPE_MAX; ++i)
2589 		if (layout_types & (1 << i))
2590 			*p++ = cpu_to_be32(i);
2591 
2592 	return 0;
2593 }
2594 
2595 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
2596 			      FATTR4_WORD0_RDATTR_ERROR)
2597 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2598 #define WORD2_ABSENT_FS_ATTRS 0
2599 
2600 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2601 static inline __be32
2602 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2603 			    void *context, int len)
2604 {
2605 	__be32 *p;
2606 
2607 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2608 	if (!p)
2609 		return nfserr_resource;
2610 
2611 	/*
2612 	 * For now we use a 0 here to indicate the null translation; in
2613 	 * the future we may place a call to translation code here.
2614 	 */
2615 	*p++ = cpu_to_be32(0); /* lfs */
2616 	*p++ = cpu_to_be32(0); /* pi */
2617 	p = xdr_encode_opaque(p, context, len);
2618 	return 0;
2619 }
2620 #else
2621 static inline __be32
2622 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2623 			    void *context, int len)
2624 { return 0; }
2625 #endif
2626 
2627 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *bmval2, u32 *rdattr_err)
2628 {
2629 	/* As per referral draft:  */
2630 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2631 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2632 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2633 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2634 			*rdattr_err = NFSERR_MOVED;
2635 		else
2636 			return nfserr_moved;
2637 	}
2638 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2639 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2640 	*bmval2 &= WORD2_ABSENT_FS_ATTRS;
2641 	return 0;
2642 }
2643 
2644 
2645 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2646 {
2647 	struct path path = exp->ex_path;
2648 	int err;
2649 
2650 	path_get(&path);
2651 	while (follow_up(&path)) {
2652 		if (path.dentry != path.mnt->mnt_root)
2653 			break;
2654 	}
2655 	err = vfs_getattr(&path, stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
2656 	path_put(&path);
2657 	return err;
2658 }
2659 
2660 static __be32
2661 nfsd4_encode_bitmap(struct xdr_stream *xdr, u32 bmval0, u32 bmval1, u32 bmval2)
2662 {
2663 	__be32 *p;
2664 
2665 	if (bmval2) {
2666 		p = xdr_reserve_space(xdr, 16);
2667 		if (!p)
2668 			goto out_resource;
2669 		*p++ = cpu_to_be32(3);
2670 		*p++ = cpu_to_be32(bmval0);
2671 		*p++ = cpu_to_be32(bmval1);
2672 		*p++ = cpu_to_be32(bmval2);
2673 	} else if (bmval1) {
2674 		p = xdr_reserve_space(xdr, 12);
2675 		if (!p)
2676 			goto out_resource;
2677 		*p++ = cpu_to_be32(2);
2678 		*p++ = cpu_to_be32(bmval0);
2679 		*p++ = cpu_to_be32(bmval1);
2680 	} else {
2681 		p = xdr_reserve_space(xdr, 8);
2682 		if (!p)
2683 			goto out_resource;
2684 		*p++ = cpu_to_be32(1);
2685 		*p++ = cpu_to_be32(bmval0);
2686 	}
2687 
2688 	return 0;
2689 out_resource:
2690 	return nfserr_resource;
2691 }
2692 
2693 /*
2694  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2695  * ourselves.
2696  */
2697 static __be32
2698 nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
2699 		struct svc_export *exp,
2700 		struct dentry *dentry, u32 *bmval,
2701 		struct svc_rqst *rqstp, int ignore_crossmnt)
2702 {
2703 	u32 bmval0 = bmval[0];
2704 	u32 bmval1 = bmval[1];
2705 	u32 bmval2 = bmval[2];
2706 	struct kstat stat;
2707 	struct svc_fh *tempfh = NULL;
2708 	struct kstatfs statfs;
2709 	__be32 *p;
2710 	int starting_len = xdr->buf->len;
2711 	int attrlen_offset;
2712 	__be32 attrlen;
2713 	u32 dummy;
2714 	u64 dummy64;
2715 	u32 rdattr_err = 0;
2716 	__be32 status;
2717 	int err;
2718 	struct nfs4_acl *acl = NULL;
2719 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2720 	void *context = NULL;
2721 	int contextlen;
2722 #endif
2723 	bool contextsupport = false;
2724 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2725 	u32 minorversion = resp->cstate.minorversion;
2726 	struct path path = {
2727 		.mnt	= exp->ex_path.mnt,
2728 		.dentry	= dentry,
2729 	};
2730 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2731 
2732 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2733 	BUG_ON(!nfsd_attrs_supported(minorversion, bmval));
2734 
2735 	if (exp->ex_fslocs.migrated) {
2736 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &bmval2, &rdattr_err);
2737 		if (status)
2738 			goto out;
2739 	}
2740 
2741 	err = vfs_getattr(&path, &stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
2742 	if (err)
2743 		goto out_nfserr;
2744 	if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
2745 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
2746 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2747 		       FATTR4_WORD1_SPACE_TOTAL))) {
2748 		err = vfs_statfs(&path, &statfs);
2749 		if (err)
2750 			goto out_nfserr;
2751 	}
2752 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2753 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2754 		status = nfserr_jukebox;
2755 		if (!tempfh)
2756 			goto out;
2757 		fh_init(tempfh, NFS4_FHSIZE);
2758 		status = fh_compose(tempfh, exp, dentry, NULL);
2759 		if (status)
2760 			goto out;
2761 		fhp = tempfh;
2762 	}
2763 	if (bmval0 & FATTR4_WORD0_ACL) {
2764 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2765 		if (err == -EOPNOTSUPP)
2766 			bmval0 &= ~FATTR4_WORD0_ACL;
2767 		else if (err == -EINVAL) {
2768 			status = nfserr_attrnotsupp;
2769 			goto out;
2770 		} else if (err != 0)
2771 			goto out_nfserr;
2772 	}
2773 
2774 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2775 	if ((bmval2 & FATTR4_WORD2_SECURITY_LABEL) ||
2776 	     bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2777 		if (exp->ex_flags & NFSEXP_SECURITY_LABEL)
2778 			err = security_inode_getsecctx(d_inode(dentry),
2779 						&context, &contextlen);
2780 		else
2781 			err = -EOPNOTSUPP;
2782 		contextsupport = (err == 0);
2783 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2784 			if (err == -EOPNOTSUPP)
2785 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2786 			else if (err)
2787 				goto out_nfserr;
2788 		}
2789 	}
2790 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2791 
2792 	status = nfsd4_encode_bitmap(xdr, bmval0, bmval1, bmval2);
2793 	if (status)
2794 		goto out;
2795 
2796 	attrlen_offset = xdr->buf->len;
2797 	p = xdr_reserve_space(xdr, 4);
2798 	if (!p)
2799 		goto out_resource;
2800 	p++;                /* to be backfilled later */
2801 
2802 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2803 		u32 supp[3];
2804 
2805 		memcpy(supp, nfsd_suppattrs[minorversion], sizeof(supp));
2806 
2807 		if (!IS_POSIXACL(dentry->d_inode))
2808 			supp[0] &= ~FATTR4_WORD0_ACL;
2809 		if (!contextsupport)
2810 			supp[2] &= ~FATTR4_WORD2_SECURITY_LABEL;
2811 		if (!supp[2]) {
2812 			p = xdr_reserve_space(xdr, 12);
2813 			if (!p)
2814 				goto out_resource;
2815 			*p++ = cpu_to_be32(2);
2816 			*p++ = cpu_to_be32(supp[0]);
2817 			*p++ = cpu_to_be32(supp[1]);
2818 		} else {
2819 			p = xdr_reserve_space(xdr, 16);
2820 			if (!p)
2821 				goto out_resource;
2822 			*p++ = cpu_to_be32(3);
2823 			*p++ = cpu_to_be32(supp[0]);
2824 			*p++ = cpu_to_be32(supp[1]);
2825 			*p++ = cpu_to_be32(supp[2]);
2826 		}
2827 	}
2828 	if (bmval0 & FATTR4_WORD0_TYPE) {
2829 		p = xdr_reserve_space(xdr, 4);
2830 		if (!p)
2831 			goto out_resource;
2832 		dummy = nfs4_file_type(stat.mode);
2833 		if (dummy == NF4BAD) {
2834 			status = nfserr_serverfault;
2835 			goto out;
2836 		}
2837 		*p++ = cpu_to_be32(dummy);
2838 	}
2839 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2840 		p = xdr_reserve_space(xdr, 4);
2841 		if (!p)
2842 			goto out_resource;
2843 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2844 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT);
2845 		else
2846 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT|
2847 						NFS4_FH_VOL_RENAME);
2848 	}
2849 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2850 		p = xdr_reserve_space(xdr, 8);
2851 		if (!p)
2852 			goto out_resource;
2853 		p = encode_change(p, &stat, d_inode(dentry), exp);
2854 	}
2855 	if (bmval0 & FATTR4_WORD0_SIZE) {
2856 		p = xdr_reserve_space(xdr, 8);
2857 		if (!p)
2858 			goto out_resource;
2859 		p = xdr_encode_hyper(p, stat.size);
2860 	}
2861 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2862 		p = xdr_reserve_space(xdr, 4);
2863 		if (!p)
2864 			goto out_resource;
2865 		*p++ = cpu_to_be32(1);
2866 	}
2867 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2868 		p = xdr_reserve_space(xdr, 4);
2869 		if (!p)
2870 			goto out_resource;
2871 		*p++ = cpu_to_be32(1);
2872 	}
2873 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2874 		p = xdr_reserve_space(xdr, 4);
2875 		if (!p)
2876 			goto out_resource;
2877 		*p++ = cpu_to_be32(0);
2878 	}
2879 	if (bmval0 & FATTR4_WORD0_FSID) {
2880 		p = xdr_reserve_space(xdr, 16);
2881 		if (!p)
2882 			goto out_resource;
2883 		if (exp->ex_fslocs.migrated) {
2884 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
2885 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
2886 		} else switch(fsid_source(fhp)) {
2887 		case FSIDSOURCE_FSID:
2888 			p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
2889 			p = xdr_encode_hyper(p, (u64)0);
2890 			break;
2891 		case FSIDSOURCE_DEV:
2892 			*p++ = cpu_to_be32(0);
2893 			*p++ = cpu_to_be32(MAJOR(stat.dev));
2894 			*p++ = cpu_to_be32(0);
2895 			*p++ = cpu_to_be32(MINOR(stat.dev));
2896 			break;
2897 		case FSIDSOURCE_UUID:
2898 			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
2899 								EX_UUID_LEN);
2900 			break;
2901 		}
2902 	}
2903 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2904 		p = xdr_reserve_space(xdr, 4);
2905 		if (!p)
2906 			goto out_resource;
2907 		*p++ = cpu_to_be32(0);
2908 	}
2909 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2910 		p = xdr_reserve_space(xdr, 4);
2911 		if (!p)
2912 			goto out_resource;
2913 		*p++ = cpu_to_be32(nn->nfsd4_lease);
2914 	}
2915 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2916 		p = xdr_reserve_space(xdr, 4);
2917 		if (!p)
2918 			goto out_resource;
2919 		*p++ = cpu_to_be32(rdattr_err);
2920 	}
2921 	if (bmval0 & FATTR4_WORD0_ACL) {
2922 		struct nfs4_ace *ace;
2923 
2924 		if (acl == NULL) {
2925 			p = xdr_reserve_space(xdr, 4);
2926 			if (!p)
2927 				goto out_resource;
2928 
2929 			*p++ = cpu_to_be32(0);
2930 			goto out_acl;
2931 		}
2932 		p = xdr_reserve_space(xdr, 4);
2933 		if (!p)
2934 			goto out_resource;
2935 		*p++ = cpu_to_be32(acl->naces);
2936 
2937 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2938 			p = xdr_reserve_space(xdr, 4*3);
2939 			if (!p)
2940 				goto out_resource;
2941 			*p++ = cpu_to_be32(ace->type);
2942 			*p++ = cpu_to_be32(ace->flag);
2943 			*p++ = cpu_to_be32(ace->access_mask &
2944 							NFS4_ACE_MASK_ALL);
2945 			status = nfsd4_encode_aclname(xdr, rqstp, ace);
2946 			if (status)
2947 				goto out;
2948 		}
2949 	}
2950 out_acl:
2951 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2952 		p = xdr_reserve_space(xdr, 4);
2953 		if (!p)
2954 			goto out_resource;
2955 		*p++ = cpu_to_be32(IS_POSIXACL(dentry->d_inode) ?
2956 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2957 	}
2958 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2959 		p = xdr_reserve_space(xdr, 4);
2960 		if (!p)
2961 			goto out_resource;
2962 		*p++ = cpu_to_be32(1);
2963 	}
2964 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2965 		p = xdr_reserve_space(xdr, 4);
2966 		if (!p)
2967 			goto out_resource;
2968 		*p++ = cpu_to_be32(0);
2969 	}
2970 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2971 		p = xdr_reserve_space(xdr, 4);
2972 		if (!p)
2973 			goto out_resource;
2974 		*p++ = cpu_to_be32(1);
2975 	}
2976 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2977 		p = xdr_reserve_space(xdr, 4);
2978 		if (!p)
2979 			goto out_resource;
2980 		*p++ = cpu_to_be32(1);
2981 	}
2982 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2983 		p = xdr_reserve_space(xdr, fhp->fh_handle.fh_size + 4);
2984 		if (!p)
2985 			goto out_resource;
2986 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base,
2987 					fhp->fh_handle.fh_size);
2988 	}
2989 	if (bmval0 & FATTR4_WORD0_FILEID) {
2990 		p = xdr_reserve_space(xdr, 8);
2991 		if (!p)
2992 			goto out_resource;
2993 		p = xdr_encode_hyper(p, stat.ino);
2994 	}
2995 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2996 		p = xdr_reserve_space(xdr, 8);
2997 		if (!p)
2998 			goto out_resource;
2999 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
3000 	}
3001 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
3002 		p = xdr_reserve_space(xdr, 8);
3003 		if (!p)
3004 			goto out_resource;
3005 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
3006 	}
3007 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
3008 		p = xdr_reserve_space(xdr, 8);
3009 		if (!p)
3010 			goto out_resource;
3011 		p = xdr_encode_hyper(p, (u64) statfs.f_files);
3012 	}
3013 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
3014 		status = nfsd4_encode_fs_locations(xdr, rqstp, exp);
3015 		if (status)
3016 			goto out;
3017 	}
3018 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
3019 		p = xdr_reserve_space(xdr, 4);
3020 		if (!p)
3021 			goto out_resource;
3022 		*p++ = cpu_to_be32(1);
3023 	}
3024 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
3025 		p = xdr_reserve_space(xdr, 8);
3026 		if (!p)
3027 			goto out_resource;
3028 		p = xdr_encode_hyper(p, exp->ex_path.mnt->mnt_sb->s_maxbytes);
3029 	}
3030 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
3031 		p = xdr_reserve_space(xdr, 4);
3032 		if (!p)
3033 			goto out_resource;
3034 		*p++ = cpu_to_be32(255);
3035 	}
3036 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
3037 		p = xdr_reserve_space(xdr, 4);
3038 		if (!p)
3039 			goto out_resource;
3040 		*p++ = cpu_to_be32(statfs.f_namelen);
3041 	}
3042 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
3043 		p = xdr_reserve_space(xdr, 8);
3044 		if (!p)
3045 			goto out_resource;
3046 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
3047 	}
3048 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
3049 		p = xdr_reserve_space(xdr, 8);
3050 		if (!p)
3051 			goto out_resource;
3052 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
3053 	}
3054 	if (bmval1 & FATTR4_WORD1_MODE) {
3055 		p = xdr_reserve_space(xdr, 4);
3056 		if (!p)
3057 			goto out_resource;
3058 		*p++ = cpu_to_be32(stat.mode & S_IALLUGO);
3059 	}
3060 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
3061 		p = xdr_reserve_space(xdr, 4);
3062 		if (!p)
3063 			goto out_resource;
3064 		*p++ = cpu_to_be32(1);
3065 	}
3066 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
3067 		p = xdr_reserve_space(xdr, 4);
3068 		if (!p)
3069 			goto out_resource;
3070 		*p++ = cpu_to_be32(stat.nlink);
3071 	}
3072 	if (bmval1 & FATTR4_WORD1_OWNER) {
3073 		status = nfsd4_encode_user(xdr, rqstp, stat.uid);
3074 		if (status)
3075 			goto out;
3076 	}
3077 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
3078 		status = nfsd4_encode_group(xdr, rqstp, stat.gid);
3079 		if (status)
3080 			goto out;
3081 	}
3082 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
3083 		p = xdr_reserve_space(xdr, 8);
3084 		if (!p)
3085 			goto out_resource;
3086 		*p++ = cpu_to_be32((u32) MAJOR(stat.rdev));
3087 		*p++ = cpu_to_be32((u32) MINOR(stat.rdev));
3088 	}
3089 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
3090 		p = xdr_reserve_space(xdr, 8);
3091 		if (!p)
3092 			goto out_resource;
3093 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
3094 		p = xdr_encode_hyper(p, dummy64);
3095 	}
3096 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
3097 		p = xdr_reserve_space(xdr, 8);
3098 		if (!p)
3099 			goto out_resource;
3100 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
3101 		p = xdr_encode_hyper(p, dummy64);
3102 	}
3103 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
3104 		p = xdr_reserve_space(xdr, 8);
3105 		if (!p)
3106 			goto out_resource;
3107 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
3108 		p = xdr_encode_hyper(p, dummy64);
3109 	}
3110 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
3111 		p = xdr_reserve_space(xdr, 8);
3112 		if (!p)
3113 			goto out_resource;
3114 		dummy64 = (u64)stat.blocks << 9;
3115 		p = xdr_encode_hyper(p, dummy64);
3116 	}
3117 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
3118 		p = xdr_reserve_space(xdr, 12);
3119 		if (!p)
3120 			goto out_resource;
3121 		p = xdr_encode_hyper(p, (s64)stat.atime.tv_sec);
3122 		*p++ = cpu_to_be32(stat.atime.tv_nsec);
3123 	}
3124 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
3125 		p = xdr_reserve_space(xdr, 12);
3126 		if (!p)
3127 			goto out_resource;
3128 		p = encode_time_delta(p, d_inode(dentry));
3129 	}
3130 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
3131 		p = xdr_reserve_space(xdr, 12);
3132 		if (!p)
3133 			goto out_resource;
3134 		p = xdr_encode_hyper(p, (s64)stat.ctime.tv_sec);
3135 		*p++ = cpu_to_be32(stat.ctime.tv_nsec);
3136 	}
3137 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
3138 		p = xdr_reserve_space(xdr, 12);
3139 		if (!p)
3140 			goto out_resource;
3141 		p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
3142 		*p++ = cpu_to_be32(stat.mtime.tv_nsec);
3143 	}
3144 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
3145 		struct kstat parent_stat;
3146 		u64 ino = stat.ino;
3147 
3148 		p = xdr_reserve_space(xdr, 8);
3149 		if (!p)
3150                 	goto out_resource;
3151 		/*
3152 		 * Get parent's attributes if not ignoring crossmount
3153 		 * and this is the root of a cross-mounted filesystem.
3154 		 */
3155 		if (ignore_crossmnt == 0 &&
3156 		    dentry == exp->ex_path.mnt->mnt_root) {
3157 			err = get_parent_attributes(exp, &parent_stat);
3158 			if (err)
3159 				goto out_nfserr;
3160 			ino = parent_stat.ino;
3161 		}
3162 		p = xdr_encode_hyper(p, ino);
3163 	}
3164 #ifdef CONFIG_NFSD_PNFS
3165 	if (bmval1 & FATTR4_WORD1_FS_LAYOUT_TYPES) {
3166 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
3167 		if (status)
3168 			goto out;
3169 	}
3170 
3171 	if (bmval2 & FATTR4_WORD2_LAYOUT_TYPES) {
3172 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
3173 		if (status)
3174 			goto out;
3175 	}
3176 
3177 	if (bmval2 & FATTR4_WORD2_LAYOUT_BLKSIZE) {
3178 		p = xdr_reserve_space(xdr, 4);
3179 		if (!p)
3180 			goto out_resource;
3181 		*p++ = cpu_to_be32(stat.blksize);
3182 	}
3183 #endif /* CONFIG_NFSD_PNFS */
3184 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
3185 		u32 supp[3];
3186 
3187 		memcpy(supp, nfsd_suppattrs[minorversion], sizeof(supp));
3188 		supp[0] &= NFSD_SUPPATTR_EXCLCREAT_WORD0;
3189 		supp[1] &= NFSD_SUPPATTR_EXCLCREAT_WORD1;
3190 		supp[2] &= NFSD_SUPPATTR_EXCLCREAT_WORD2;
3191 
3192 		status = nfsd4_encode_bitmap(xdr, supp[0], supp[1], supp[2]);
3193 		if (status)
3194 			goto out;
3195 	}
3196 
3197 	if (bmval2 & FATTR4_WORD2_CHANGE_ATTR_TYPE) {
3198 		p = xdr_reserve_space(xdr, 4);
3199 		if (!p)
3200 			goto out_resource;
3201 		if (IS_I_VERSION(d_inode(dentry)))
3202 			*p++ = cpu_to_be32(NFS4_CHANGE_TYPE_IS_MONOTONIC_INCR);
3203 		else
3204 			*p++ = cpu_to_be32(NFS4_CHANGE_TYPE_IS_TIME_METADATA);
3205 	}
3206 
3207 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
3208 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
3209 		status = nfsd4_encode_security_label(xdr, rqstp, context,
3210 								contextlen);
3211 		if (status)
3212 			goto out;
3213 	}
3214 #endif
3215 
3216 	if (bmval2 & FATTR4_WORD2_XATTR_SUPPORT) {
3217 		p = xdr_reserve_space(xdr, 4);
3218 		if (!p)
3219 			goto out_resource;
3220 		err = xattr_supported_namespace(d_inode(dentry),
3221 						XATTR_USER_PREFIX);
3222 		*p++ = cpu_to_be32(err == 0);
3223 	}
3224 
3225 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
3226 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
3227 	status = nfs_ok;
3228 
3229 out:
3230 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
3231 	if (context)
3232 		security_release_secctx(context, contextlen);
3233 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
3234 	kfree(acl);
3235 	if (tempfh) {
3236 		fh_put(tempfh);
3237 		kfree(tempfh);
3238 	}
3239 	if (status)
3240 		xdr_truncate_encode(xdr, starting_len);
3241 	return status;
3242 out_nfserr:
3243 	status = nfserrno(err);
3244 	goto out;
3245 out_resource:
3246 	status = nfserr_resource;
3247 	goto out;
3248 }
3249 
3250 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
3251 				struct xdr_buf *buf, __be32 *p, int bytes)
3252 {
3253 	xdr->scratch.iov_len = 0;
3254 	memset(buf, 0, sizeof(struct xdr_buf));
3255 	buf->head[0].iov_base = p;
3256 	buf->head[0].iov_len = 0;
3257 	buf->len = 0;
3258 	xdr->buf = buf;
3259 	xdr->iov = buf->head;
3260 	xdr->p = p;
3261 	xdr->end = (void *)p + bytes;
3262 	buf->buflen = bytes;
3263 }
3264 
3265 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
3266 			struct svc_fh *fhp, struct svc_export *exp,
3267 			struct dentry *dentry, u32 *bmval,
3268 			struct svc_rqst *rqstp, int ignore_crossmnt)
3269 {
3270 	struct xdr_buf dummy;
3271 	struct xdr_stream xdr;
3272 	__be32 ret;
3273 
3274 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
3275 	ret = nfsd4_encode_fattr(&xdr, fhp, exp, dentry, bmval, rqstp,
3276 							ignore_crossmnt);
3277 	*p = xdr.p;
3278 	return ret;
3279 }
3280 
3281 static inline int attributes_need_mount(u32 *bmval)
3282 {
3283 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
3284 		return 1;
3285 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
3286 		return 1;
3287 	return 0;
3288 }
3289 
3290 static __be32
3291 nfsd4_encode_dirent_fattr(struct xdr_stream *xdr, struct nfsd4_readdir *cd,
3292 			const char *name, int namlen)
3293 {
3294 	struct svc_export *exp = cd->rd_fhp->fh_export;
3295 	struct dentry *dentry;
3296 	__be32 nfserr;
3297 	int ignore_crossmnt = 0;
3298 
3299 	dentry = lookup_positive_unlocked(name, cd->rd_fhp->fh_dentry, namlen);
3300 	if (IS_ERR(dentry))
3301 		return nfserrno(PTR_ERR(dentry));
3302 
3303 	exp_get(exp);
3304 	/*
3305 	 * In the case of a mountpoint, the client may be asking for
3306 	 * attributes that are only properties of the underlying filesystem
3307 	 * as opposed to the cross-mounted file system. In such a case,
3308 	 * we will not follow the cross mount and will fill the attribtutes
3309 	 * directly from the mountpoint dentry.
3310 	 */
3311 	if (nfsd_mountpoint(dentry, exp)) {
3312 		int err;
3313 
3314 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
3315 				&& !attributes_need_mount(cd->rd_bmval)) {
3316 			ignore_crossmnt = 1;
3317 			goto out_encode;
3318 		}
3319 		/*
3320 		 * Why the heck aren't we just using nfsd_lookup??
3321 		 * Different "."/".." handling?  Something else?
3322 		 * At least, add a comment here to explain....
3323 		 */
3324 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
3325 		if (err) {
3326 			nfserr = nfserrno(err);
3327 			goto out_put;
3328 		}
3329 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
3330 		if (nfserr)
3331 			goto out_put;
3332 
3333 	}
3334 out_encode:
3335 	nfserr = nfsd4_encode_fattr(xdr, NULL, exp, dentry, cd->rd_bmval,
3336 					cd->rd_rqstp, ignore_crossmnt);
3337 out_put:
3338 	dput(dentry);
3339 	exp_put(exp);
3340 	return nfserr;
3341 }
3342 
3343 static __be32 *
3344 nfsd4_encode_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
3345 {
3346 	__be32 *p;
3347 
3348 	p = xdr_reserve_space(xdr, 20);
3349 	if (!p)
3350 		return NULL;
3351 	*p++ = htonl(2);
3352 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
3353 	*p++ = htonl(0);			 /* bmval1 */
3354 
3355 	*p++ = htonl(4);     /* attribute length */
3356 	*p++ = nfserr;       /* no htonl */
3357 	return p;
3358 }
3359 
3360 static int
3361 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
3362 		    loff_t offset, u64 ino, unsigned int d_type)
3363 {
3364 	struct readdir_cd *ccd = ccdv;
3365 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
3366 	struct xdr_stream *xdr = cd->xdr;
3367 	int start_offset = xdr->buf->len;
3368 	int cookie_offset;
3369 	u32 name_and_cookie;
3370 	int entry_bytes;
3371 	__be32 nfserr = nfserr_toosmall;
3372 	__be64 wire_offset;
3373 	__be32 *p;
3374 
3375 	/* In nfsv4, "." and ".." never make it onto the wire.. */
3376 	if (name && isdotent(name, namlen)) {
3377 		cd->common.err = nfs_ok;
3378 		return 0;
3379 	}
3380 
3381 	if (cd->cookie_offset) {
3382 		wire_offset = cpu_to_be64(offset);
3383 		write_bytes_to_xdr_buf(xdr->buf, cd->cookie_offset,
3384 							&wire_offset, 8);
3385 	}
3386 
3387 	p = xdr_reserve_space(xdr, 4);
3388 	if (!p)
3389 		goto fail;
3390 	*p++ = xdr_one;                             /* mark entry present */
3391 	cookie_offset = xdr->buf->len;
3392 	p = xdr_reserve_space(xdr, 3*4 + namlen);
3393 	if (!p)
3394 		goto fail;
3395 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
3396 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
3397 
3398 	nfserr = nfsd4_encode_dirent_fattr(xdr, cd, name, namlen);
3399 	switch (nfserr) {
3400 	case nfs_ok:
3401 		break;
3402 	case nfserr_resource:
3403 		nfserr = nfserr_toosmall;
3404 		goto fail;
3405 	case nfserr_noent:
3406 		xdr_truncate_encode(xdr, start_offset);
3407 		goto skip_entry;
3408 	default:
3409 		/*
3410 		 * If the client requested the RDATTR_ERROR attribute,
3411 		 * we stuff the error code into this attribute
3412 		 * and continue.  If this attribute was not requested,
3413 		 * then in accordance with the spec, we fail the
3414 		 * entire READDIR operation(!)
3415 		 */
3416 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
3417 			goto fail;
3418 		p = nfsd4_encode_rdattr_error(xdr, nfserr);
3419 		if (p == NULL) {
3420 			nfserr = nfserr_toosmall;
3421 			goto fail;
3422 		}
3423 	}
3424 	nfserr = nfserr_toosmall;
3425 	entry_bytes = xdr->buf->len - start_offset;
3426 	if (entry_bytes > cd->rd_maxcount)
3427 		goto fail;
3428 	cd->rd_maxcount -= entry_bytes;
3429 	/*
3430 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so
3431 	 * let's always let through the first entry, at least:
3432 	 */
3433 	if (!cd->rd_dircount)
3434 		goto fail;
3435 	name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8;
3436 	if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
3437 		goto fail;
3438 	cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
3439 
3440 	cd->cookie_offset = cookie_offset;
3441 skip_entry:
3442 	cd->common.err = nfs_ok;
3443 	return 0;
3444 fail:
3445 	xdr_truncate_encode(xdr, start_offset);
3446 	cd->common.err = nfserr;
3447 	return -EINVAL;
3448 }
3449 
3450 static __be32
3451 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
3452 {
3453 	__be32 *p;
3454 
3455 	p = xdr_reserve_space(xdr, sizeof(stateid_t));
3456 	if (!p)
3457 		return nfserr_resource;
3458 	*p++ = cpu_to_be32(sid->si_generation);
3459 	p = xdr_encode_opaque_fixed(p, &sid->si_opaque,
3460 					sizeof(stateid_opaque_t));
3461 	return 0;
3462 }
3463 
3464 static __be32
3465 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
3466 {
3467 	struct xdr_stream *xdr = &resp->xdr;
3468 	__be32 *p;
3469 
3470 	p = xdr_reserve_space(xdr, 8);
3471 	if (!p)
3472 		return nfserr_resource;
3473 	*p++ = cpu_to_be32(access->ac_supported);
3474 	*p++ = cpu_to_be32(access->ac_resp_access);
3475 	return 0;
3476 }
3477 
3478 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
3479 {
3480 	struct xdr_stream *xdr = &resp->xdr;
3481 	__be32 *p;
3482 
3483 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 8);
3484 	if (!p)
3485 		return nfserr_resource;
3486 	p = xdr_encode_opaque_fixed(p, bcts->sessionid.data,
3487 					NFS4_MAX_SESSIONID_LEN);
3488 	*p++ = cpu_to_be32(bcts->dir);
3489 	/* Upshifting from TCP to RDMA is not supported */
3490 	*p++ = cpu_to_be32(0);
3491 	return 0;
3492 }
3493 
3494 static __be32
3495 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
3496 {
3497 	struct xdr_stream *xdr = &resp->xdr;
3498 
3499 	return nfsd4_encode_stateid(xdr, &close->cl_stateid);
3500 }
3501 
3502 
3503 static __be32
3504 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
3505 {
3506 	struct xdr_stream *xdr = &resp->xdr;
3507 	__be32 *p;
3508 
3509 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3510 	if (!p)
3511 		return nfserr_resource;
3512 	p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
3513 						NFS4_VERIFIER_SIZE);
3514 	return 0;
3515 }
3516 
3517 static __be32
3518 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
3519 {
3520 	struct xdr_stream *xdr = &resp->xdr;
3521 	__be32 *p;
3522 
3523 	p = xdr_reserve_space(xdr, 20);
3524 	if (!p)
3525 		return nfserr_resource;
3526 	encode_cinfo(p, &create->cr_cinfo);
3527 	return nfsd4_encode_bitmap(xdr, create->cr_bmval[0],
3528 			create->cr_bmval[1], create->cr_bmval[2]);
3529 }
3530 
3531 static __be32
3532 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
3533 {
3534 	struct svc_fh *fhp = getattr->ga_fhp;
3535 	struct xdr_stream *xdr = &resp->xdr;
3536 
3537 	return nfsd4_encode_fattr(xdr, fhp, fhp->fh_export, fhp->fh_dentry,
3538 				    getattr->ga_bmval, resp->rqstp, 0);
3539 }
3540 
3541 static __be32
3542 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
3543 {
3544 	struct xdr_stream *xdr = &resp->xdr;
3545 	struct svc_fh *fhp = *fhpp;
3546 	unsigned int len;
3547 	__be32 *p;
3548 
3549 	len = fhp->fh_handle.fh_size;
3550 	p = xdr_reserve_space(xdr, len + 4);
3551 	if (!p)
3552 		return nfserr_resource;
3553 	p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base, len);
3554 	return 0;
3555 }
3556 
3557 /*
3558 * Including all fields other than the name, a LOCK4denied structure requires
3559 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
3560 */
3561 static __be32
3562 nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld)
3563 {
3564 	struct xdr_netobj *conf = &ld->ld_owner;
3565 	__be32 *p;
3566 
3567 again:
3568 	p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len));
3569 	if (!p) {
3570 		/*
3571 		 * Don't fail to return the result just because we can't
3572 		 * return the conflicting open:
3573 		 */
3574 		if (conf->len) {
3575 			kfree(conf->data);
3576 			conf->len = 0;
3577 			conf->data = NULL;
3578 			goto again;
3579 		}
3580 		return nfserr_resource;
3581 	}
3582 	p = xdr_encode_hyper(p, ld->ld_start);
3583 	p = xdr_encode_hyper(p, ld->ld_length);
3584 	*p++ = cpu_to_be32(ld->ld_type);
3585 	if (conf->len) {
3586 		p = xdr_encode_opaque_fixed(p, &ld->ld_clientid, 8);
3587 		p = xdr_encode_opaque(p, conf->data, conf->len);
3588 		kfree(conf->data);
3589 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
3590 		p = xdr_encode_hyper(p, (u64)0); /* clientid */
3591 		*p++ = cpu_to_be32(0); /* length of owner name */
3592 	}
3593 	return nfserr_denied;
3594 }
3595 
3596 static __be32
3597 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
3598 {
3599 	struct xdr_stream *xdr = &resp->xdr;
3600 
3601 	if (!nfserr)
3602 		nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid);
3603 	else if (nfserr == nfserr_denied)
3604 		nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied);
3605 
3606 	return nfserr;
3607 }
3608 
3609 static __be32
3610 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
3611 {
3612 	struct xdr_stream *xdr = &resp->xdr;
3613 
3614 	if (nfserr == nfserr_denied)
3615 		nfsd4_encode_lock_denied(xdr, &lockt->lt_denied);
3616 	return nfserr;
3617 }
3618 
3619 static __be32
3620 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
3621 {
3622 	struct xdr_stream *xdr = &resp->xdr;
3623 
3624 	return nfsd4_encode_stateid(xdr, &locku->lu_stateid);
3625 }
3626 
3627 
3628 static __be32
3629 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
3630 {
3631 	struct xdr_stream *xdr = &resp->xdr;
3632 	__be32 *p;
3633 
3634 	p = xdr_reserve_space(xdr, 20);
3635 	if (!p)
3636 		return nfserr_resource;
3637 	p = encode_cinfo(p, &link->li_cinfo);
3638 	return 0;
3639 }
3640 
3641 
3642 static __be32
3643 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
3644 {
3645 	struct xdr_stream *xdr = &resp->xdr;
3646 	__be32 *p;
3647 
3648 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
3649 	if (nfserr)
3650 		return nfserr;
3651 	p = xdr_reserve_space(xdr, 24);
3652 	if (!p)
3653 		return nfserr_resource;
3654 	p = encode_cinfo(p, &open->op_cinfo);
3655 	*p++ = cpu_to_be32(open->op_rflags);
3656 
3657 	nfserr = nfsd4_encode_bitmap(xdr, open->op_bmval[0], open->op_bmval[1],
3658 					open->op_bmval[2]);
3659 	if (nfserr)
3660 		return nfserr;
3661 
3662 	p = xdr_reserve_space(xdr, 4);
3663 	if (!p)
3664 		return nfserr_resource;
3665 
3666 	*p++ = cpu_to_be32(open->op_delegate_type);
3667 	switch (open->op_delegate_type) {
3668 	case NFS4_OPEN_DELEGATE_NONE:
3669 		break;
3670 	case NFS4_OPEN_DELEGATE_READ:
3671 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3672 		if (nfserr)
3673 			return nfserr;
3674 		p = xdr_reserve_space(xdr, 20);
3675 		if (!p)
3676 			return nfserr_resource;
3677 		*p++ = cpu_to_be32(open->op_recall);
3678 
3679 		/*
3680 		 * TODO: ACE's in delegations
3681 		 */
3682 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3683 		*p++ = cpu_to_be32(0);
3684 		*p++ = cpu_to_be32(0);
3685 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3686 		break;
3687 	case NFS4_OPEN_DELEGATE_WRITE:
3688 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3689 		if (nfserr)
3690 			return nfserr;
3691 		p = xdr_reserve_space(xdr, 32);
3692 		if (!p)
3693 			return nfserr_resource;
3694 		*p++ = cpu_to_be32(0);
3695 
3696 		/*
3697 		 * TODO: space_limit's in delegations
3698 		 */
3699 		*p++ = cpu_to_be32(NFS4_LIMIT_SIZE);
3700 		*p++ = cpu_to_be32(~(u32)0);
3701 		*p++ = cpu_to_be32(~(u32)0);
3702 
3703 		/*
3704 		 * TODO: ACE's in delegations
3705 		 */
3706 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3707 		*p++ = cpu_to_be32(0);
3708 		*p++ = cpu_to_be32(0);
3709 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3710 		break;
3711 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
3712 		switch (open->op_why_no_deleg) {
3713 		case WND4_CONTENTION:
3714 		case WND4_RESOURCE:
3715 			p = xdr_reserve_space(xdr, 8);
3716 			if (!p)
3717 				return nfserr_resource;
3718 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3719 			/* deleg signaling not supported yet: */
3720 			*p++ = cpu_to_be32(0);
3721 			break;
3722 		default:
3723 			p = xdr_reserve_space(xdr, 4);
3724 			if (!p)
3725 				return nfserr_resource;
3726 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3727 		}
3728 		break;
3729 	default:
3730 		BUG();
3731 	}
3732 	/* XXX save filehandle here */
3733 	return 0;
3734 }
3735 
3736 static __be32
3737 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
3738 {
3739 	struct xdr_stream *xdr = &resp->xdr;
3740 
3741 	return nfsd4_encode_stateid(xdr, &oc->oc_resp_stateid);
3742 }
3743 
3744 static __be32
3745 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
3746 {
3747 	struct xdr_stream *xdr = &resp->xdr;
3748 
3749 	return nfsd4_encode_stateid(xdr, &od->od_stateid);
3750 }
3751 
3752 static __be32 nfsd4_encode_splice_read(
3753 				struct nfsd4_compoundres *resp,
3754 				struct nfsd4_read *read,
3755 				struct file *file, unsigned long maxcount)
3756 {
3757 	struct xdr_stream *xdr = &resp->xdr;
3758 	struct xdr_buf *buf = xdr->buf;
3759 	u32 eof;
3760 	int space_left;
3761 	__be32 nfserr;
3762 	__be32 *p = xdr->p - 2;
3763 
3764 	/* Make sure there will be room for padding if needed */
3765 	if (xdr->end - xdr->p < 1)
3766 		return nfserr_resource;
3767 
3768 	nfserr = nfsd_splice_read(read->rd_rqstp, read->rd_fhp,
3769 				  file, read->rd_offset, &maxcount, &eof);
3770 	read->rd_length = maxcount;
3771 	if (nfserr) {
3772 		/*
3773 		 * nfsd_splice_actor may have already messed with the
3774 		 * page length; reset it so as not to confuse
3775 		 * xdr_truncate_encode:
3776 		 */
3777 		buf->page_len = 0;
3778 		return nfserr;
3779 	}
3780 
3781 	*(p++) = htonl(eof);
3782 	*(p++) = htonl(maxcount);
3783 
3784 	buf->page_len = maxcount;
3785 	buf->len += maxcount;
3786 	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
3787 							/ PAGE_SIZE;
3788 
3789 	/* Use rest of head for padding and remaining ops: */
3790 	buf->tail[0].iov_base = xdr->p;
3791 	buf->tail[0].iov_len = 0;
3792 	xdr->iov = buf->tail;
3793 	if (maxcount&3) {
3794 		int pad = 4 - (maxcount&3);
3795 
3796 		*(xdr->p++) = 0;
3797 
3798 		buf->tail[0].iov_base += maxcount&3;
3799 		buf->tail[0].iov_len = pad;
3800 		buf->len += pad;
3801 	}
3802 
3803 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
3804 				buf->buflen - buf->len);
3805 	buf->buflen = buf->len + space_left;
3806 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
3807 
3808 	return 0;
3809 }
3810 
3811 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
3812 				 struct nfsd4_read *read,
3813 				 struct file *file, unsigned long maxcount)
3814 {
3815 	struct xdr_stream *xdr = &resp->xdr;
3816 	u32 eof;
3817 	int starting_len = xdr->buf->len - 8;
3818 	__be32 nfserr;
3819 	__be32 tmp;
3820 	int pad;
3821 
3822 	read->rd_vlen = xdr_reserve_space_vec(xdr, resp->rqstp->rq_vec, maxcount);
3823 	if (read->rd_vlen < 0)
3824 		return nfserr_resource;
3825 
3826 	nfserr = nfsd_readv(resp->rqstp, read->rd_fhp, file, read->rd_offset,
3827 			    resp->rqstp->rq_vec, read->rd_vlen, &maxcount,
3828 			    &eof);
3829 	read->rd_length = maxcount;
3830 	if (nfserr)
3831 		return nfserr;
3832 	if (svc_encode_read_payload(resp->rqstp, starting_len + 8, maxcount))
3833 		return nfserr_io;
3834 	xdr_truncate_encode(xdr, starting_len + 8 + xdr_align_size(maxcount));
3835 
3836 	tmp = htonl(eof);
3837 	write_bytes_to_xdr_buf(xdr->buf, starting_len    , &tmp, 4);
3838 	tmp = htonl(maxcount);
3839 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
3840 
3841 	tmp = xdr_zero;
3842 	pad = (maxcount&3) ? 4 - (maxcount&3) : 0;
3843 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 8 + maxcount,
3844 								&tmp, pad);
3845 	return 0;
3846 
3847 }
3848 
3849 static __be32
3850 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
3851 		  struct nfsd4_read *read)
3852 {
3853 	unsigned long maxcount;
3854 	struct xdr_stream *xdr = &resp->xdr;
3855 	struct file *file;
3856 	int starting_len = xdr->buf->len;
3857 	__be32 *p;
3858 
3859 	if (nfserr)
3860 		return nfserr;
3861 	file = read->rd_nf->nf_file;
3862 
3863 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
3864 	if (!p) {
3865 		WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
3866 		return nfserr_resource;
3867 	}
3868 	if (resp->xdr.buf->page_len &&
3869 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
3870 		WARN_ON_ONCE(1);
3871 		return nfserr_resource;
3872 	}
3873 	xdr_commit_encode(xdr);
3874 
3875 	maxcount = svc_max_payload(resp->rqstp);
3876 	maxcount = min_t(unsigned long, maxcount,
3877 			 (xdr->buf->buflen - xdr->buf->len));
3878 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
3879 
3880 	if (file->f_op->splice_read &&
3881 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
3882 		nfserr = nfsd4_encode_splice_read(resp, read, file, maxcount);
3883 	else
3884 		nfserr = nfsd4_encode_readv(resp, read, file, maxcount);
3885 
3886 	if (nfserr)
3887 		xdr_truncate_encode(xdr, starting_len);
3888 
3889 	return nfserr;
3890 }
3891 
3892 static __be32
3893 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3894 {
3895 	int maxcount;
3896 	__be32 wire_count;
3897 	int zero = 0;
3898 	struct xdr_stream *xdr = &resp->xdr;
3899 	int length_offset = xdr->buf->len;
3900 	__be32 *p;
3901 
3902 	p = xdr_reserve_space(xdr, 4);
3903 	if (!p)
3904 		return nfserr_resource;
3905 	maxcount = PAGE_SIZE;
3906 
3907 	p = xdr_reserve_space(xdr, maxcount);
3908 	if (!p)
3909 		return nfserr_resource;
3910 	/*
3911 	 * XXX: By default, vfs_readlink() will truncate symlinks if they
3912 	 * would overflow the buffer.  Is this kosher in NFSv4?  If not, one
3913 	 * easy fix is: if vfs_readlink() precisely fills the buffer, assume
3914 	 * that truncation occurred, and return NFS4ERR_RESOURCE.
3915 	 */
3916 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
3917 						(char *)p, &maxcount);
3918 	if (nfserr == nfserr_isdir)
3919 		nfserr = nfserr_inval;
3920 	if (nfserr) {
3921 		xdr_truncate_encode(xdr, length_offset);
3922 		return nfserr;
3923 	}
3924 
3925 	wire_count = htonl(maxcount);
3926 	write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
3927 	xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
3928 	if (maxcount & 3)
3929 		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
3930 						&zero, 4 - (maxcount&3));
3931 	return 0;
3932 }
3933 
3934 static __be32
3935 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3936 {
3937 	int maxcount;
3938 	int bytes_left;
3939 	loff_t offset;
3940 	__be64 wire_offset;
3941 	struct xdr_stream *xdr = &resp->xdr;
3942 	int starting_len = xdr->buf->len;
3943 	__be32 *p;
3944 
3945 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3946 	if (!p)
3947 		return nfserr_resource;
3948 
3949 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3950 	*p++ = cpu_to_be32(0);
3951 	*p++ = cpu_to_be32(0);
3952 	resp->xdr.buf->head[0].iov_len = ((char *)resp->xdr.p)
3953 				- (char *)resp->xdr.buf->head[0].iov_base;
3954 
3955 	/*
3956 	 * Number of bytes left for directory entries allowing for the
3957 	 * final 8 bytes of the readdir and a following failed op:
3958 	 */
3959 	bytes_left = xdr->buf->buflen - xdr->buf->len
3960 			- COMPOUND_ERR_SLACK_SPACE - 8;
3961 	if (bytes_left < 0) {
3962 		nfserr = nfserr_resource;
3963 		goto err_no_verf;
3964 	}
3965 	maxcount = svc_max_payload(resp->rqstp);
3966 	maxcount = min_t(u32, readdir->rd_maxcount, maxcount);
3967 	/*
3968 	 * Note the rfc defines rd_maxcount as the size of the
3969 	 * READDIR4resok structure, which includes the verifier above
3970 	 * and the 8 bytes encoded at the end of this function:
3971 	 */
3972 	if (maxcount < 16) {
3973 		nfserr = nfserr_toosmall;
3974 		goto err_no_verf;
3975 	}
3976 	maxcount = min_t(int, maxcount-16, bytes_left);
3977 
3978 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
3979 	if (!readdir->rd_dircount)
3980 		readdir->rd_dircount = svc_max_payload(resp->rqstp);
3981 
3982 	readdir->xdr = xdr;
3983 	readdir->rd_maxcount = maxcount;
3984 	readdir->common.err = 0;
3985 	readdir->cookie_offset = 0;
3986 
3987 	offset = readdir->rd_cookie;
3988 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3989 			      &offset,
3990 			      &readdir->common, nfsd4_encode_dirent);
3991 	if (nfserr == nfs_ok &&
3992 	    readdir->common.err == nfserr_toosmall &&
3993 	    xdr->buf->len == starting_len + 8) {
3994 		/* nothing encoded; which limit did we hit?: */
3995 		if (maxcount - 16 < bytes_left)
3996 			/* It was the fault of rd_maxcount: */
3997 			nfserr = nfserr_toosmall;
3998 		else
3999 			/* We ran out of buffer space: */
4000 			nfserr = nfserr_resource;
4001 	}
4002 	if (nfserr)
4003 		goto err_no_verf;
4004 
4005 	if (readdir->cookie_offset) {
4006 		wire_offset = cpu_to_be64(offset);
4007 		write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset,
4008 							&wire_offset, 8);
4009 	}
4010 
4011 	p = xdr_reserve_space(xdr, 8);
4012 	if (!p) {
4013 		WARN_ON_ONCE(1);
4014 		goto err_no_verf;
4015 	}
4016 	*p++ = 0;	/* no more entries */
4017 	*p++ = htonl(readdir->common.err == nfserr_eof);
4018 
4019 	return 0;
4020 err_no_verf:
4021 	xdr_truncate_encode(xdr, starting_len);
4022 	return nfserr;
4023 }
4024 
4025 static __be32
4026 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
4027 {
4028 	struct xdr_stream *xdr = &resp->xdr;
4029 	__be32 *p;
4030 
4031 	p = xdr_reserve_space(xdr, 20);
4032 	if (!p)
4033 		return nfserr_resource;
4034 	p = encode_cinfo(p, &remove->rm_cinfo);
4035 	return 0;
4036 }
4037 
4038 static __be32
4039 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
4040 {
4041 	struct xdr_stream *xdr = &resp->xdr;
4042 	__be32 *p;
4043 
4044 	p = xdr_reserve_space(xdr, 40);
4045 	if (!p)
4046 		return nfserr_resource;
4047 	p = encode_cinfo(p, &rename->rn_sinfo);
4048 	p = encode_cinfo(p, &rename->rn_tinfo);
4049 	return 0;
4050 }
4051 
4052 static __be32
4053 nfsd4_do_encode_secinfo(struct xdr_stream *xdr, struct svc_export *exp)
4054 {
4055 	u32 i, nflavs, supported;
4056 	struct exp_flavor_info *flavs;
4057 	struct exp_flavor_info def_flavs[2];
4058 	__be32 *p, *flavorsp;
4059 	static bool report = true;
4060 
4061 	if (exp->ex_nflavors) {
4062 		flavs = exp->ex_flavors;
4063 		nflavs = exp->ex_nflavors;
4064 	} else { /* Handling of some defaults in absence of real secinfo: */
4065 		flavs = def_flavs;
4066 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
4067 			nflavs = 2;
4068 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
4069 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
4070 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
4071 			nflavs = 1;
4072 			flavs[0].pseudoflavor
4073 					= svcauth_gss_flavor(exp->ex_client);
4074 		} else {
4075 			nflavs = 1;
4076 			flavs[0].pseudoflavor
4077 					= exp->ex_client->flavour->flavour;
4078 		}
4079 	}
4080 
4081 	supported = 0;
4082 	p = xdr_reserve_space(xdr, 4);
4083 	if (!p)
4084 		return nfserr_resource;
4085 	flavorsp = p++;		/* to be backfilled later */
4086 
4087 	for (i = 0; i < nflavs; i++) {
4088 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
4089 		struct rpcsec_gss_info info;
4090 
4091 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
4092 			supported++;
4093 			p = xdr_reserve_space(xdr, 4 + 4 +
4094 					      XDR_LEN(info.oid.len) + 4 + 4);
4095 			if (!p)
4096 				return nfserr_resource;
4097 			*p++ = cpu_to_be32(RPC_AUTH_GSS);
4098 			p = xdr_encode_opaque(p,  info.oid.data, info.oid.len);
4099 			*p++ = cpu_to_be32(info.qop);
4100 			*p++ = cpu_to_be32(info.service);
4101 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
4102 			supported++;
4103 			p = xdr_reserve_space(xdr, 4);
4104 			if (!p)
4105 				return nfserr_resource;
4106 			*p++ = cpu_to_be32(pf);
4107 		} else {
4108 			if (report)
4109 				pr_warn("NFS: SECINFO: security flavor %u "
4110 					"is not supported\n", pf);
4111 		}
4112 	}
4113 
4114 	if (nflavs != supported)
4115 		report = false;
4116 	*flavorsp = htonl(supported);
4117 	return 0;
4118 }
4119 
4120 static __be32
4121 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
4122 		     struct nfsd4_secinfo *secinfo)
4123 {
4124 	struct xdr_stream *xdr = &resp->xdr;
4125 
4126 	return nfsd4_do_encode_secinfo(xdr, secinfo->si_exp);
4127 }
4128 
4129 static __be32
4130 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
4131 		     struct nfsd4_secinfo_no_name *secinfo)
4132 {
4133 	struct xdr_stream *xdr = &resp->xdr;
4134 
4135 	return nfsd4_do_encode_secinfo(xdr, secinfo->sin_exp);
4136 }
4137 
4138 /*
4139  * The SETATTR encode routine is special -- it always encodes a bitmap,
4140  * regardless of the error status.
4141  */
4142 static __be32
4143 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
4144 {
4145 	struct xdr_stream *xdr = &resp->xdr;
4146 	__be32 *p;
4147 
4148 	p = xdr_reserve_space(xdr, 16);
4149 	if (!p)
4150 		return nfserr_resource;
4151 	if (nfserr) {
4152 		*p++ = cpu_to_be32(3);
4153 		*p++ = cpu_to_be32(0);
4154 		*p++ = cpu_to_be32(0);
4155 		*p++ = cpu_to_be32(0);
4156 	}
4157 	else {
4158 		*p++ = cpu_to_be32(3);
4159 		*p++ = cpu_to_be32(setattr->sa_bmval[0]);
4160 		*p++ = cpu_to_be32(setattr->sa_bmval[1]);
4161 		*p++ = cpu_to_be32(setattr->sa_bmval[2]);
4162 	}
4163 	return nfserr;
4164 }
4165 
4166 static __be32
4167 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
4168 {
4169 	struct xdr_stream *xdr = &resp->xdr;
4170 	__be32 *p;
4171 
4172 	if (!nfserr) {
4173 		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
4174 		if (!p)
4175 			return nfserr_resource;
4176 		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
4177 		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
4178 						NFS4_VERIFIER_SIZE);
4179 	}
4180 	else if (nfserr == nfserr_clid_inuse) {
4181 		p = xdr_reserve_space(xdr, 8);
4182 		if (!p)
4183 			return nfserr_resource;
4184 		*p++ = cpu_to_be32(0);
4185 		*p++ = cpu_to_be32(0);
4186 	}
4187 	return nfserr;
4188 }
4189 
4190 static __be32
4191 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
4192 {
4193 	struct xdr_stream *xdr = &resp->xdr;
4194 	__be32 *p;
4195 
4196 	p = xdr_reserve_space(xdr, 16);
4197 	if (!p)
4198 		return nfserr_resource;
4199 	*p++ = cpu_to_be32(write->wr_bytes_written);
4200 	*p++ = cpu_to_be32(write->wr_how_written);
4201 	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
4202 						NFS4_VERIFIER_SIZE);
4203 	return 0;
4204 }
4205 
4206 static __be32
4207 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
4208 			 struct nfsd4_exchange_id *exid)
4209 {
4210 	struct xdr_stream *xdr = &resp->xdr;
4211 	__be32 *p;
4212 	char *major_id;
4213 	char *server_scope;
4214 	int major_id_sz;
4215 	int server_scope_sz;
4216 	uint64_t minor_id = 0;
4217 	struct nfsd_net *nn = net_generic(SVC_NET(resp->rqstp), nfsd_net_id);
4218 
4219 	major_id = nn->nfsd_name;
4220 	major_id_sz = strlen(nn->nfsd_name);
4221 	server_scope = nn->nfsd_name;
4222 	server_scope_sz = strlen(nn->nfsd_name);
4223 
4224 	p = xdr_reserve_space(xdr,
4225 		8 /* eir_clientid */ +
4226 		4 /* eir_sequenceid */ +
4227 		4 /* eir_flags */ +
4228 		4 /* spr_how */);
4229 	if (!p)
4230 		return nfserr_resource;
4231 
4232 	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
4233 	*p++ = cpu_to_be32(exid->seqid);
4234 	*p++ = cpu_to_be32(exid->flags);
4235 
4236 	*p++ = cpu_to_be32(exid->spa_how);
4237 
4238 	switch (exid->spa_how) {
4239 	case SP4_NONE:
4240 		break;
4241 	case SP4_MACH_CRED:
4242 		/* spo_must_enforce bitmap: */
4243 		nfserr = nfsd4_encode_bitmap(xdr,
4244 					exid->spo_must_enforce[0],
4245 					exid->spo_must_enforce[1],
4246 					exid->spo_must_enforce[2]);
4247 		if (nfserr)
4248 			return nfserr;
4249 		/* spo_must_allow bitmap: */
4250 		nfserr = nfsd4_encode_bitmap(xdr,
4251 					exid->spo_must_allow[0],
4252 					exid->spo_must_allow[1],
4253 					exid->spo_must_allow[2]);
4254 		if (nfserr)
4255 			return nfserr;
4256 		break;
4257 	default:
4258 		WARN_ON_ONCE(1);
4259 	}
4260 
4261 	p = xdr_reserve_space(xdr,
4262 		8 /* so_minor_id */ +
4263 		4 /* so_major_id.len */ +
4264 		(XDR_QUADLEN(major_id_sz) * 4) +
4265 		4 /* eir_server_scope.len */ +
4266 		(XDR_QUADLEN(server_scope_sz) * 4) +
4267 		4 /* eir_server_impl_id.count (0) */);
4268 	if (!p)
4269 		return nfserr_resource;
4270 
4271 	/* The server_owner struct */
4272 	p = xdr_encode_hyper(p, minor_id);      /* Minor id */
4273 	/* major id */
4274 	p = xdr_encode_opaque(p, major_id, major_id_sz);
4275 
4276 	/* Server scope */
4277 	p = xdr_encode_opaque(p, server_scope, server_scope_sz);
4278 
4279 	/* Implementation id */
4280 	*p++ = cpu_to_be32(0);	/* zero length nfs_impl_id4 array */
4281 	return 0;
4282 }
4283 
4284 static __be32
4285 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
4286 			    struct nfsd4_create_session *sess)
4287 {
4288 	struct xdr_stream *xdr = &resp->xdr;
4289 	__be32 *p;
4290 
4291 	p = xdr_reserve_space(xdr, 24);
4292 	if (!p)
4293 		return nfserr_resource;
4294 	p = xdr_encode_opaque_fixed(p, sess->sessionid.data,
4295 					NFS4_MAX_SESSIONID_LEN);
4296 	*p++ = cpu_to_be32(sess->seqid);
4297 	*p++ = cpu_to_be32(sess->flags);
4298 
4299 	p = xdr_reserve_space(xdr, 28);
4300 	if (!p)
4301 		return nfserr_resource;
4302 	*p++ = cpu_to_be32(0); /* headerpadsz */
4303 	*p++ = cpu_to_be32(sess->fore_channel.maxreq_sz);
4304 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_sz);
4305 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_cached);
4306 	*p++ = cpu_to_be32(sess->fore_channel.maxops);
4307 	*p++ = cpu_to_be32(sess->fore_channel.maxreqs);
4308 	*p++ = cpu_to_be32(sess->fore_channel.nr_rdma_attrs);
4309 
4310 	if (sess->fore_channel.nr_rdma_attrs) {
4311 		p = xdr_reserve_space(xdr, 4);
4312 		if (!p)
4313 			return nfserr_resource;
4314 		*p++ = cpu_to_be32(sess->fore_channel.rdma_attrs);
4315 	}
4316 
4317 	p = xdr_reserve_space(xdr, 28);
4318 	if (!p)
4319 		return nfserr_resource;
4320 	*p++ = cpu_to_be32(0); /* headerpadsz */
4321 	*p++ = cpu_to_be32(sess->back_channel.maxreq_sz);
4322 	*p++ = cpu_to_be32(sess->back_channel.maxresp_sz);
4323 	*p++ = cpu_to_be32(sess->back_channel.maxresp_cached);
4324 	*p++ = cpu_to_be32(sess->back_channel.maxops);
4325 	*p++ = cpu_to_be32(sess->back_channel.maxreqs);
4326 	*p++ = cpu_to_be32(sess->back_channel.nr_rdma_attrs);
4327 
4328 	if (sess->back_channel.nr_rdma_attrs) {
4329 		p = xdr_reserve_space(xdr, 4);
4330 		if (!p)
4331 			return nfserr_resource;
4332 		*p++ = cpu_to_be32(sess->back_channel.rdma_attrs);
4333 	}
4334 	return 0;
4335 }
4336 
4337 static __be32
4338 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
4339 		      struct nfsd4_sequence *seq)
4340 {
4341 	struct xdr_stream *xdr = &resp->xdr;
4342 	__be32 *p;
4343 
4344 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 20);
4345 	if (!p)
4346 		return nfserr_resource;
4347 	p = xdr_encode_opaque_fixed(p, seq->sessionid.data,
4348 					NFS4_MAX_SESSIONID_LEN);
4349 	*p++ = cpu_to_be32(seq->seqid);
4350 	*p++ = cpu_to_be32(seq->slotid);
4351 	/* Note slotid's are numbered from zero: */
4352 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_highest_slotid */
4353 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_target_highest_slotid */
4354 	*p++ = cpu_to_be32(seq->status_flags);
4355 
4356 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
4357 	return 0;
4358 }
4359 
4360 static __be32
4361 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
4362 			  struct nfsd4_test_stateid *test_stateid)
4363 {
4364 	struct xdr_stream *xdr = &resp->xdr;
4365 	struct nfsd4_test_stateid_id *stateid, *next;
4366 	__be32 *p;
4367 
4368 	p = xdr_reserve_space(xdr, 4 + (4 * test_stateid->ts_num_ids));
4369 	if (!p)
4370 		return nfserr_resource;
4371 	*p++ = htonl(test_stateid->ts_num_ids);
4372 
4373 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
4374 		*p++ = stateid->ts_id_status;
4375 	}
4376 
4377 	return 0;
4378 }
4379 
4380 #ifdef CONFIG_NFSD_PNFS
4381 static __be32
4382 nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
4383 		struct nfsd4_getdeviceinfo *gdev)
4384 {
4385 	struct xdr_stream *xdr = &resp->xdr;
4386 	const struct nfsd4_layout_ops *ops;
4387 	u32 starting_len = xdr->buf->len, needed_len;
4388 	__be32 *p;
4389 
4390 	p = xdr_reserve_space(xdr, 4);
4391 	if (!p)
4392 		return nfserr_resource;
4393 
4394 	*p++ = cpu_to_be32(gdev->gd_layout_type);
4395 
4396 	/* If maxcount is 0 then just update notifications */
4397 	if (gdev->gd_maxcount != 0) {
4398 		ops = nfsd4_layout_ops[gdev->gd_layout_type];
4399 		nfserr = ops->encode_getdeviceinfo(xdr, gdev);
4400 		if (nfserr) {
4401 			/*
4402 			 * We don't bother to burden the layout drivers with
4403 			 * enforcing gd_maxcount, just tell the client to
4404 			 * come back with a bigger buffer if it's not enough.
4405 			 */
4406 			if (xdr->buf->len + 4 > gdev->gd_maxcount)
4407 				goto toosmall;
4408 			return nfserr;
4409 		}
4410 	}
4411 
4412 	if (gdev->gd_notify_types) {
4413 		p = xdr_reserve_space(xdr, 4 + 4);
4414 		if (!p)
4415 			return nfserr_resource;
4416 		*p++ = cpu_to_be32(1);			/* bitmap length */
4417 		*p++ = cpu_to_be32(gdev->gd_notify_types);
4418 	} else {
4419 		p = xdr_reserve_space(xdr, 4);
4420 		if (!p)
4421 			return nfserr_resource;
4422 		*p++ = 0;
4423 	}
4424 
4425 	return 0;
4426 toosmall:
4427 	dprintk("%s: maxcount too small\n", __func__);
4428 	needed_len = xdr->buf->len + 4 /* notifications */;
4429 	xdr_truncate_encode(xdr, starting_len);
4430 	p = xdr_reserve_space(xdr, 4);
4431 	if (!p)
4432 		return nfserr_resource;
4433 	*p++ = cpu_to_be32(needed_len);
4434 	return nfserr_toosmall;
4435 }
4436 
4437 static __be32
4438 nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr,
4439 		struct nfsd4_layoutget *lgp)
4440 {
4441 	struct xdr_stream *xdr = &resp->xdr;
4442 	const struct nfsd4_layout_ops *ops;
4443 	__be32 *p;
4444 
4445 	p = xdr_reserve_space(xdr, 36 + sizeof(stateid_opaque_t));
4446 	if (!p)
4447 		return nfserr_resource;
4448 
4449 	*p++ = cpu_to_be32(1);	/* we always set return-on-close */
4450 	*p++ = cpu_to_be32(lgp->lg_sid.si_generation);
4451 	p = xdr_encode_opaque_fixed(p, &lgp->lg_sid.si_opaque,
4452 				    sizeof(stateid_opaque_t));
4453 
4454 	*p++ = cpu_to_be32(1);	/* we always return a single layout */
4455 	p = xdr_encode_hyper(p, lgp->lg_seg.offset);
4456 	p = xdr_encode_hyper(p, lgp->lg_seg.length);
4457 	*p++ = cpu_to_be32(lgp->lg_seg.iomode);
4458 	*p++ = cpu_to_be32(lgp->lg_layout_type);
4459 
4460 	ops = nfsd4_layout_ops[lgp->lg_layout_type];
4461 	return ops->encode_layoutget(xdr, lgp);
4462 }
4463 
4464 static __be32
4465 nfsd4_encode_layoutcommit(struct nfsd4_compoundres *resp, __be32 nfserr,
4466 			  struct nfsd4_layoutcommit *lcp)
4467 {
4468 	struct xdr_stream *xdr = &resp->xdr;
4469 	__be32 *p;
4470 
4471 	p = xdr_reserve_space(xdr, 4);
4472 	if (!p)
4473 		return nfserr_resource;
4474 	*p++ = cpu_to_be32(lcp->lc_size_chg);
4475 	if (lcp->lc_size_chg) {
4476 		p = xdr_reserve_space(xdr, 8);
4477 		if (!p)
4478 			return nfserr_resource;
4479 		p = xdr_encode_hyper(p, lcp->lc_newsize);
4480 	}
4481 
4482 	return 0;
4483 }
4484 
4485 static __be32
4486 nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
4487 		struct nfsd4_layoutreturn *lrp)
4488 {
4489 	struct xdr_stream *xdr = &resp->xdr;
4490 	__be32 *p;
4491 
4492 	p = xdr_reserve_space(xdr, 4);
4493 	if (!p)
4494 		return nfserr_resource;
4495 	*p++ = cpu_to_be32(lrp->lrs_present);
4496 	if (lrp->lrs_present)
4497 		return nfsd4_encode_stateid(xdr, &lrp->lr_sid);
4498 	return 0;
4499 }
4500 #endif /* CONFIG_NFSD_PNFS */
4501 
4502 static __be32
4503 nfsd42_encode_write_res(struct nfsd4_compoundres *resp,
4504 		struct nfsd42_write_res *write, bool sync)
4505 {
4506 	__be32 *p;
4507 	p = xdr_reserve_space(&resp->xdr, 4);
4508 	if (!p)
4509 		return nfserr_resource;
4510 
4511 	if (sync)
4512 		*p++ = cpu_to_be32(0);
4513 	else {
4514 		__be32 nfserr;
4515 		*p++ = cpu_to_be32(1);
4516 		nfserr = nfsd4_encode_stateid(&resp->xdr, &write->cb_stateid);
4517 		if (nfserr)
4518 			return nfserr;
4519 	}
4520 	p = xdr_reserve_space(&resp->xdr, 8 + 4 + NFS4_VERIFIER_SIZE);
4521 	if (!p)
4522 		return nfserr_resource;
4523 
4524 	p = xdr_encode_hyper(p, write->wr_bytes_written);
4525 	*p++ = cpu_to_be32(write->wr_stable_how);
4526 	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
4527 				    NFS4_VERIFIER_SIZE);
4528 	return nfs_ok;
4529 }
4530 
4531 static __be32
4532 nfsd42_encode_nl4_server(struct nfsd4_compoundres *resp, struct nl4_server *ns)
4533 {
4534 	struct xdr_stream *xdr = &resp->xdr;
4535 	struct nfs42_netaddr *addr;
4536 	__be32 *p;
4537 
4538 	p = xdr_reserve_space(xdr, 4);
4539 	*p++ = cpu_to_be32(ns->nl4_type);
4540 
4541 	switch (ns->nl4_type) {
4542 	case NL4_NETADDR:
4543 		addr = &ns->u.nl4_addr;
4544 
4545 		/* netid_len, netid, uaddr_len, uaddr (port included
4546 		 * in RPCBIND_MAXUADDRLEN)
4547 		 */
4548 		p = xdr_reserve_space(xdr,
4549 			4 /* netid len */ +
4550 			(XDR_QUADLEN(addr->netid_len) * 4) +
4551 			4 /* uaddr len */ +
4552 			(XDR_QUADLEN(addr->addr_len) * 4));
4553 		if (!p)
4554 			return nfserr_resource;
4555 
4556 		*p++ = cpu_to_be32(addr->netid_len);
4557 		p = xdr_encode_opaque_fixed(p, addr->netid,
4558 					    addr->netid_len);
4559 		*p++ = cpu_to_be32(addr->addr_len);
4560 		p = xdr_encode_opaque_fixed(p, addr->addr,
4561 					addr->addr_len);
4562 		break;
4563 	default:
4564 		WARN_ON_ONCE(ns->nl4_type != NL4_NETADDR);
4565 		return nfserr_inval;
4566 	}
4567 
4568 	return 0;
4569 }
4570 
4571 static __be32
4572 nfsd4_encode_copy(struct nfsd4_compoundres *resp, __be32 nfserr,
4573 		  struct nfsd4_copy *copy)
4574 {
4575 	__be32 *p;
4576 
4577 	nfserr = nfsd42_encode_write_res(resp, &copy->cp_res,
4578 			copy->cp_synchronous);
4579 	if (nfserr)
4580 		return nfserr;
4581 
4582 	p = xdr_reserve_space(&resp->xdr, 4 + 4);
4583 	*p++ = xdr_one; /* cr_consecutive */
4584 	*p++ = cpu_to_be32(copy->cp_synchronous);
4585 	return 0;
4586 }
4587 
4588 static __be32
4589 nfsd4_encode_offload_status(struct nfsd4_compoundres *resp, __be32 nfserr,
4590 			    struct nfsd4_offload_status *os)
4591 {
4592 	struct xdr_stream *xdr = &resp->xdr;
4593 	__be32 *p;
4594 
4595 	p = xdr_reserve_space(xdr, 8 + 4);
4596 	if (!p)
4597 		return nfserr_resource;
4598 	p = xdr_encode_hyper(p, os->count);
4599 	*p++ = cpu_to_be32(0);
4600 	return nfserr;
4601 }
4602 
4603 static __be32
4604 nfsd4_encode_read_plus_data(struct nfsd4_compoundres *resp,
4605 			    struct nfsd4_read *read,
4606 			    unsigned long *maxcount, u32 *eof,
4607 			    loff_t *pos)
4608 {
4609 	struct xdr_stream *xdr = &resp->xdr;
4610 	struct file *file = read->rd_nf->nf_file;
4611 	int starting_len = xdr->buf->len;
4612 	loff_t hole_pos;
4613 	__be32 nfserr;
4614 	__be32 *p, tmp;
4615 	__be64 tmp64;
4616 
4617 	hole_pos = pos ? *pos : vfs_llseek(file, read->rd_offset, SEEK_HOLE);
4618 	if (hole_pos > read->rd_offset)
4619 		*maxcount = min_t(unsigned long, *maxcount, hole_pos - read->rd_offset);
4620 	*maxcount = min_t(unsigned long, *maxcount, (xdr->buf->buflen - xdr->buf->len));
4621 
4622 	/* Content type, offset, byte count */
4623 	p = xdr_reserve_space(xdr, 4 + 8 + 4);
4624 	if (!p)
4625 		return nfserr_resource;
4626 
4627 	read->rd_vlen = xdr_reserve_space_vec(xdr, resp->rqstp->rq_vec, *maxcount);
4628 	if (read->rd_vlen < 0)
4629 		return nfserr_resource;
4630 
4631 	nfserr = nfsd_readv(resp->rqstp, read->rd_fhp, file, read->rd_offset,
4632 			    resp->rqstp->rq_vec, read->rd_vlen, maxcount, eof);
4633 	if (nfserr)
4634 		return nfserr;
4635 
4636 	tmp = htonl(NFS4_CONTENT_DATA);
4637 	write_bytes_to_xdr_buf(xdr->buf, starting_len,      &tmp,   4);
4638 	tmp64 = cpu_to_be64(read->rd_offset);
4639 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4,  &tmp64, 8);
4640 	tmp = htonl(*maxcount);
4641 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 12, &tmp,   4);
4642 	return nfs_ok;
4643 }
4644 
4645 static __be32
4646 nfsd4_encode_read_plus_hole(struct nfsd4_compoundres *resp,
4647 			    struct nfsd4_read *read,
4648 			    unsigned long *maxcount, u32 *eof)
4649 {
4650 	struct file *file = read->rd_nf->nf_file;
4651 	loff_t data_pos = vfs_llseek(file, read->rd_offset, SEEK_DATA);
4652 	loff_t f_size = i_size_read(file_inode(file));
4653 	unsigned long count;
4654 	__be32 *p;
4655 
4656 	if (data_pos == -ENXIO)
4657 		data_pos = f_size;
4658 	else if (data_pos <= read->rd_offset || (data_pos < f_size && data_pos % PAGE_SIZE))
4659 		return nfsd4_encode_read_plus_data(resp, read, maxcount, eof, &f_size);
4660 	count = data_pos - read->rd_offset;
4661 
4662 	/* Content type, offset, byte count */
4663 	p = xdr_reserve_space(&resp->xdr, 4 + 8 + 8);
4664 	if (!p)
4665 		return nfserr_resource;
4666 
4667 	*p++ = htonl(NFS4_CONTENT_HOLE);
4668 	 p   = xdr_encode_hyper(p, read->rd_offset);
4669 	 p   = xdr_encode_hyper(p, count);
4670 
4671 	*eof = (read->rd_offset + count) >= f_size;
4672 	*maxcount = min_t(unsigned long, count, *maxcount);
4673 	return nfs_ok;
4674 }
4675 
4676 static __be32
4677 nfsd4_encode_read_plus(struct nfsd4_compoundres *resp, __be32 nfserr,
4678 		       struct nfsd4_read *read)
4679 {
4680 	unsigned long maxcount, count;
4681 	struct xdr_stream *xdr = &resp->xdr;
4682 	struct file *file;
4683 	int starting_len = xdr->buf->len;
4684 	int last_segment = xdr->buf->len;
4685 	int segments = 0;
4686 	__be32 *p, tmp;
4687 	bool is_data;
4688 	loff_t pos;
4689 	u32 eof;
4690 
4691 	if (nfserr)
4692 		return nfserr;
4693 	file = read->rd_nf->nf_file;
4694 
4695 	/* eof flag, segment count */
4696 	p = xdr_reserve_space(xdr, 4 + 4);
4697 	if (!p)
4698 		return nfserr_resource;
4699 	xdr_commit_encode(xdr);
4700 
4701 	maxcount = svc_max_payload(resp->rqstp);
4702 	maxcount = min_t(unsigned long, maxcount,
4703 			 (xdr->buf->buflen - xdr->buf->len));
4704 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
4705 	count    = maxcount;
4706 
4707 	eof = read->rd_offset >= i_size_read(file_inode(file));
4708 	if (eof)
4709 		goto out;
4710 
4711 	pos = vfs_llseek(file, read->rd_offset, SEEK_HOLE);
4712 	is_data = pos > read->rd_offset;
4713 
4714 	while (count > 0 && !eof) {
4715 		maxcount = count;
4716 		if (is_data)
4717 			nfserr = nfsd4_encode_read_plus_data(resp, read, &maxcount, &eof,
4718 						segments == 0 ? &pos : NULL);
4719 		else
4720 			nfserr = nfsd4_encode_read_plus_hole(resp, read, &maxcount, &eof);
4721 		if (nfserr)
4722 			goto out;
4723 		count -= maxcount;
4724 		read->rd_offset += maxcount;
4725 		is_data = !is_data;
4726 		last_segment = xdr->buf->len;
4727 		segments++;
4728 	}
4729 
4730 out:
4731 	if (nfserr && segments == 0)
4732 		xdr_truncate_encode(xdr, starting_len);
4733 	else {
4734 		tmp = htonl(eof);
4735 		write_bytes_to_xdr_buf(xdr->buf, starting_len,     &tmp, 4);
4736 		tmp = htonl(segments);
4737 		write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
4738 		if (nfserr) {
4739 			xdr_truncate_encode(xdr, last_segment);
4740 			nfserr = nfs_ok;
4741 		}
4742 	}
4743 
4744 	return nfserr;
4745 }
4746 
4747 static __be32
4748 nfsd4_encode_copy_notify(struct nfsd4_compoundres *resp, __be32 nfserr,
4749 			 struct nfsd4_copy_notify *cn)
4750 {
4751 	struct xdr_stream *xdr = &resp->xdr;
4752 	__be32 *p;
4753 
4754 	if (nfserr)
4755 		return nfserr;
4756 
4757 	/* 8 sec, 4 nsec */
4758 	p = xdr_reserve_space(xdr, 12);
4759 	if (!p)
4760 		return nfserr_resource;
4761 
4762 	/* cnr_lease_time */
4763 	p = xdr_encode_hyper(p, cn->cpn_sec);
4764 	*p++ = cpu_to_be32(cn->cpn_nsec);
4765 
4766 	/* cnr_stateid */
4767 	nfserr = nfsd4_encode_stateid(xdr, &cn->cpn_cnr_stateid);
4768 	if (nfserr)
4769 		return nfserr;
4770 
4771 	/* cnr_src.nl_nsvr */
4772 	p = xdr_reserve_space(xdr, 4);
4773 	if (!p)
4774 		return nfserr_resource;
4775 
4776 	*p++ = cpu_to_be32(1);
4777 
4778 	return nfsd42_encode_nl4_server(resp, &cn->cpn_src);
4779 }
4780 
4781 static __be32
4782 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
4783 		  struct nfsd4_seek *seek)
4784 {
4785 	__be32 *p;
4786 
4787 	p = xdr_reserve_space(&resp->xdr, 4 + 8);
4788 	*p++ = cpu_to_be32(seek->seek_eof);
4789 	p = xdr_encode_hyper(p, seek->seek_pos);
4790 
4791 	return 0;
4792 }
4793 
4794 static __be32
4795 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
4796 {
4797 	return nfserr;
4798 }
4799 
4800 /*
4801  * Encode kmalloc-ed buffer in to XDR stream.
4802  */
4803 static __be32
4804 nfsd4_vbuf_to_stream(struct xdr_stream *xdr, char *buf, u32 buflen)
4805 {
4806 	u32 cplen;
4807 	__be32 *p;
4808 
4809 	cplen = min_t(unsigned long, buflen,
4810 		      ((void *)xdr->end - (void *)xdr->p));
4811 	p = xdr_reserve_space(xdr, cplen);
4812 	if (!p)
4813 		return nfserr_resource;
4814 
4815 	memcpy(p, buf, cplen);
4816 	buf += cplen;
4817 	buflen -= cplen;
4818 
4819 	while (buflen) {
4820 		cplen = min_t(u32, buflen, PAGE_SIZE);
4821 		p = xdr_reserve_space(xdr, cplen);
4822 		if (!p)
4823 			return nfserr_resource;
4824 
4825 		memcpy(p, buf, cplen);
4826 
4827 		if (cplen < PAGE_SIZE) {
4828 			/*
4829 			 * We're done, with a length that wasn't page
4830 			 * aligned, so possibly not word aligned. Pad
4831 			 * any trailing bytes with 0.
4832 			 */
4833 			xdr_encode_opaque_fixed(p, NULL, cplen);
4834 			break;
4835 		}
4836 
4837 		buflen -= PAGE_SIZE;
4838 		buf += PAGE_SIZE;
4839 	}
4840 
4841 	return 0;
4842 }
4843 
4844 static __be32
4845 nfsd4_encode_getxattr(struct nfsd4_compoundres *resp, __be32 nfserr,
4846 		      struct nfsd4_getxattr *getxattr)
4847 {
4848 	struct xdr_stream *xdr = &resp->xdr;
4849 	__be32 *p, err;
4850 
4851 	p = xdr_reserve_space(xdr, 4);
4852 	if (!p)
4853 		return nfserr_resource;
4854 
4855 	*p = cpu_to_be32(getxattr->getxa_len);
4856 
4857 	if (getxattr->getxa_len == 0)
4858 		return 0;
4859 
4860 	err = nfsd4_vbuf_to_stream(xdr, getxattr->getxa_buf,
4861 				    getxattr->getxa_len);
4862 
4863 	kvfree(getxattr->getxa_buf);
4864 
4865 	return err;
4866 }
4867 
4868 static __be32
4869 nfsd4_encode_setxattr(struct nfsd4_compoundres *resp, __be32 nfserr,
4870 		      struct nfsd4_setxattr *setxattr)
4871 {
4872 	struct xdr_stream *xdr = &resp->xdr;
4873 	__be32 *p;
4874 
4875 	p = xdr_reserve_space(xdr, 20);
4876 	if (!p)
4877 		return nfserr_resource;
4878 
4879 	encode_cinfo(p, &setxattr->setxa_cinfo);
4880 
4881 	return 0;
4882 }
4883 
4884 /*
4885  * See if there are cookie values that can be rejected outright.
4886  */
4887 static __be32
4888 nfsd4_listxattr_validate_cookie(struct nfsd4_listxattrs *listxattrs,
4889 				u32 *offsetp)
4890 {
4891 	u64 cookie = listxattrs->lsxa_cookie;
4892 
4893 	/*
4894 	 * If the cookie is larger than the maximum number we can fit
4895 	 * in either the buffer we just got back from vfs_listxattr, or,
4896 	 * XDR-encoded, in the return buffer, it's invalid.
4897 	 */
4898 	if (cookie > (listxattrs->lsxa_len) / (XATTR_USER_PREFIX_LEN + 2))
4899 		return nfserr_badcookie;
4900 
4901 	if (cookie > (listxattrs->lsxa_maxcount /
4902 		      (XDR_QUADLEN(XATTR_USER_PREFIX_LEN + 2) + 4)))
4903 		return nfserr_badcookie;
4904 
4905 	*offsetp = (u32)cookie;
4906 	return 0;
4907 }
4908 
4909 static __be32
4910 nfsd4_encode_listxattrs(struct nfsd4_compoundres *resp, __be32 nfserr,
4911 			struct nfsd4_listxattrs *listxattrs)
4912 {
4913 	struct xdr_stream *xdr = &resp->xdr;
4914 	u32 cookie_offset, count_offset, eof;
4915 	u32 left, xdrleft, slen, count;
4916 	u32 xdrlen, offset;
4917 	u64 cookie;
4918 	char *sp;
4919 	__be32 status, tmp;
4920 	__be32 *p;
4921 	u32 nuser;
4922 
4923 	eof = 1;
4924 
4925 	status = nfsd4_listxattr_validate_cookie(listxattrs, &offset);
4926 	if (status)
4927 		goto out;
4928 
4929 	/*
4930 	 * Reserve space for the cookie and the name array count. Record
4931 	 * the offsets to save them later.
4932 	 */
4933 	cookie_offset = xdr->buf->len;
4934 	count_offset = cookie_offset + 8;
4935 	p = xdr_reserve_space(xdr, 12);
4936 	if (!p) {
4937 		status = nfserr_resource;
4938 		goto out;
4939 	}
4940 
4941 	count = 0;
4942 	left = listxattrs->lsxa_len;
4943 	sp = listxattrs->lsxa_buf;
4944 	nuser = 0;
4945 
4946 	xdrleft = listxattrs->lsxa_maxcount;
4947 
4948 	while (left > 0 && xdrleft > 0) {
4949 		slen = strlen(sp);
4950 
4951 		/*
4952 		 * Check if this is a "user." attribute, skip it if not.
4953 		 */
4954 		if (strncmp(sp, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN))
4955 			goto contloop;
4956 
4957 		slen -= XATTR_USER_PREFIX_LEN;
4958 		xdrlen = 4 + ((slen + 3) & ~3);
4959 		if (xdrlen > xdrleft) {
4960 			if (count == 0) {
4961 				/*
4962 				 * Can't even fit the first attribute name.
4963 				 */
4964 				status = nfserr_toosmall;
4965 				goto out;
4966 			}
4967 			eof = 0;
4968 			goto wreof;
4969 		}
4970 
4971 		left -= XATTR_USER_PREFIX_LEN;
4972 		sp += XATTR_USER_PREFIX_LEN;
4973 		if (nuser++ < offset)
4974 			goto contloop;
4975 
4976 
4977 		p = xdr_reserve_space(xdr, xdrlen);
4978 		if (!p) {
4979 			status = nfserr_resource;
4980 			goto out;
4981 		}
4982 
4983 		xdr_encode_opaque(p, sp, slen);
4984 
4985 		xdrleft -= xdrlen;
4986 		count++;
4987 contloop:
4988 		sp += slen + 1;
4989 		left -= slen + 1;
4990 	}
4991 
4992 	/*
4993 	 * If there were user attributes to copy, but we didn't copy
4994 	 * any, the offset was too large (e.g. the cookie was invalid).
4995 	 */
4996 	if (nuser > 0 && count == 0) {
4997 		status = nfserr_badcookie;
4998 		goto out;
4999 	}
5000 
5001 wreof:
5002 	p = xdr_reserve_space(xdr, 4);
5003 	if (!p) {
5004 		status = nfserr_resource;
5005 		goto out;
5006 	}
5007 	*p = cpu_to_be32(eof);
5008 
5009 	cookie = offset + count;
5010 
5011 	write_bytes_to_xdr_buf(xdr->buf, cookie_offset, &cookie, 8);
5012 	tmp = cpu_to_be32(count);
5013 	write_bytes_to_xdr_buf(xdr->buf, count_offset, &tmp, 4);
5014 out:
5015 	if (listxattrs->lsxa_len)
5016 		kvfree(listxattrs->lsxa_buf);
5017 	return status;
5018 }
5019 
5020 static __be32
5021 nfsd4_encode_removexattr(struct nfsd4_compoundres *resp, __be32 nfserr,
5022 			 struct nfsd4_removexattr *removexattr)
5023 {
5024 	struct xdr_stream *xdr = &resp->xdr;
5025 	__be32 *p;
5026 
5027 	p = xdr_reserve_space(xdr, 20);
5028 	if (!p)
5029 		return nfserr_resource;
5030 
5031 	p = encode_cinfo(p, &removexattr->rmxa_cinfo);
5032 	return 0;
5033 }
5034 
5035 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
5036 
5037 /*
5038  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
5039  * since we don't need to filter out obsolete ops as this is
5040  * done in the decoding phase.
5041  */
5042 static const nfsd4_enc nfsd4_enc_ops[] = {
5043 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
5044 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
5045 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
5046 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
5047 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
5048 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
5049 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
5050 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
5051 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
5052 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
5053 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
5054 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
5055 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
5056 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
5057 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
5058 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
5059 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
5060 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
5061 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
5062 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
5063 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
5064 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
5065 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
5066 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
5067 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
5068 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
5069 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
5070 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
5071 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
5072 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
5073 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
5074 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
5075 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
5076 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
5077 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
5078 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
5079 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
5080 
5081 	/* NFSv4.1 operations */
5082 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
5083 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
5084 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
5085 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
5086 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
5087 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
5088 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
5089 #ifdef CONFIG_NFSD_PNFS
5090 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_getdeviceinfo,
5091 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
5092 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_layoutcommit,
5093 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_layoutget,
5094 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_layoutreturn,
5095 #else
5096 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
5097 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
5098 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
5099 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
5100 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
5101 #endif
5102 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
5103 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
5104 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
5105 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
5106 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
5107 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
5108 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
5109 
5110 	/* NFSv4.2 operations */
5111 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
5112 	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_copy,
5113 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_copy_notify,
5114 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
5115 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
5116 	[OP_LAYOUTERROR]	= (nfsd4_enc)nfsd4_encode_noop,
5117 	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,
5118 	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,
5119 	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_offload_status,
5120 	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_read_plus,
5121 	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,
5122 	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,
5123 	[OP_CLONE]		= (nfsd4_enc)nfsd4_encode_noop,
5124 
5125 	/* RFC 8276 extended atributes operations */
5126 	[OP_GETXATTR]		= (nfsd4_enc)nfsd4_encode_getxattr,
5127 	[OP_SETXATTR]		= (nfsd4_enc)nfsd4_encode_setxattr,
5128 	[OP_LISTXATTRS]		= (nfsd4_enc)nfsd4_encode_listxattrs,
5129 	[OP_REMOVEXATTR]	= (nfsd4_enc)nfsd4_encode_removexattr,
5130 };
5131 
5132 /*
5133  * Calculate whether we still have space to encode repsize bytes.
5134  * There are two considerations:
5135  *     - For NFS versions >=4.1, the size of the reply must stay within
5136  *       session limits
5137  *     - For all NFS versions, we must stay within limited preallocated
5138  *       buffer space.
5139  *
5140  * This is called before the operation is processed, so can only provide
5141  * an upper estimate.  For some nonidempotent operations (such as
5142  * getattr), it's not necessarily a problem if that estimate is wrong,
5143  * as we can fail it after processing without significant side effects.
5144  */
5145 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
5146 {
5147 	struct xdr_buf *buf = &resp->rqstp->rq_res;
5148 	struct nfsd4_slot *slot = resp->cstate.slot;
5149 
5150 	if (buf->len + respsize <= buf->buflen)
5151 		return nfs_ok;
5152 	if (!nfsd4_has_session(&resp->cstate))
5153 		return nfserr_resource;
5154 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
5155 		WARN_ON_ONCE(1);
5156 		return nfserr_rep_too_big_to_cache;
5157 	}
5158 	return nfserr_rep_too_big;
5159 }
5160 
5161 void
5162 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
5163 {
5164 	struct xdr_stream *xdr = &resp->xdr;
5165 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
5166 	struct svc_rqst *rqstp = resp->rqstp;
5167 	const struct nfsd4_operation *opdesc = op->opdesc;
5168 	int post_err_offset;
5169 	nfsd4_enc encoder;
5170 	__be32 *p;
5171 
5172 	p = xdr_reserve_space(xdr, 8);
5173 	if (!p) {
5174 		WARN_ON_ONCE(1);
5175 		return;
5176 	}
5177 	*p++ = cpu_to_be32(op->opnum);
5178 	post_err_offset = xdr->buf->len;
5179 
5180 	if (op->opnum == OP_ILLEGAL)
5181 		goto status;
5182 	if (op->status && opdesc &&
5183 			!(opdesc->op_flags & OP_NONTRIVIAL_ERROR_ENCODE))
5184 		goto status;
5185 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
5186 	       !nfsd4_enc_ops[op->opnum]);
5187 	encoder = nfsd4_enc_ops[op->opnum];
5188 	op->status = encoder(resp, op->status, &op->u);
5189 	if (opdesc && opdesc->op_release)
5190 		opdesc->op_release(&op->u);
5191 	xdr_commit_encode(xdr);
5192 
5193 	/* nfsd4_check_resp_size guarantees enough room for error status */
5194 	if (!op->status) {
5195 		int space_needed = 0;
5196 		if (!nfsd4_last_compound_op(rqstp))
5197 			space_needed = COMPOUND_ERR_SLACK_SPACE;
5198 		op->status = nfsd4_check_resp_size(resp, space_needed);
5199 	}
5200 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
5201 		struct nfsd4_slot *slot = resp->cstate.slot;
5202 
5203 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
5204 			op->status = nfserr_rep_too_big_to_cache;
5205 		else
5206 			op->status = nfserr_rep_too_big;
5207 	}
5208 	if (op->status == nfserr_resource ||
5209 	    op->status == nfserr_rep_too_big ||
5210 	    op->status == nfserr_rep_too_big_to_cache) {
5211 		/*
5212 		 * The operation may have already been encoded or
5213 		 * partially encoded.  No op returns anything additional
5214 		 * in the case of one of these three errors, so we can
5215 		 * just truncate back to after the status.  But it's a
5216 		 * bug if we had to do this on a non-idempotent op:
5217 		 */
5218 		warn_on_nonidempotent_op(op);
5219 		xdr_truncate_encode(xdr, post_err_offset);
5220 	}
5221 	if (so) {
5222 		int len = xdr->buf->len - post_err_offset;
5223 
5224 		so->so_replay.rp_status = op->status;
5225 		so->so_replay.rp_buflen = len;
5226 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
5227 						so->so_replay.rp_buf, len);
5228 	}
5229 status:
5230 	/* Note that op->status is already in network byte order: */
5231 	write_bytes_to_xdr_buf(xdr->buf, post_err_offset - 4, &op->status, 4);
5232 }
5233 
5234 /*
5235  * Encode the reply stored in the stateowner reply cache
5236  *
5237  * XDR note: do not encode rp->rp_buflen: the buffer contains the
5238  * previously sent already encoded operation.
5239  */
5240 void
5241 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
5242 {
5243 	__be32 *p;
5244 	struct nfs4_replay *rp = op->replay;
5245 
5246 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
5247 	if (!p) {
5248 		WARN_ON_ONCE(1);
5249 		return;
5250 	}
5251 	*p++ = cpu_to_be32(op->opnum);
5252 	*p++ = rp->rp_status;  /* already xdr'ed */
5253 
5254 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
5255 }
5256 
5257 int
5258 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p)
5259 {
5260         return xdr_ressize_check(rqstp, p);
5261 }
5262 
5263 void nfsd4_release_compoundargs(struct svc_rqst *rqstp)
5264 {
5265 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
5266 
5267 	if (args->ops != args->iops) {
5268 		kfree(args->ops);
5269 		args->ops = args->iops;
5270 	}
5271 	kfree(args->tmpp);
5272 	args->tmpp = NULL;
5273 	while (args->to_free) {
5274 		struct svcxdr_tmpbuf *tb = args->to_free;
5275 		args->to_free = tb->next;
5276 		kfree(tb);
5277 	}
5278 }
5279 
5280 int
5281 nfs4svc_decode_voidarg(struct svc_rqst *rqstp, __be32 *p)
5282 {
5283 	return 1;
5284 }
5285 
5286 int
5287 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p)
5288 {
5289 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
5290 
5291 	if (rqstp->rq_arg.head[0].iov_len % 4) {
5292 		/* client is nuts */
5293 		dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)",
5294 			__func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid));
5295 		return 0;
5296 	}
5297 	args->p = p;
5298 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
5299 	args->pagelist = rqstp->rq_arg.pages;
5300 	args->pagelen = rqstp->rq_arg.page_len;
5301 	args->tail = false;
5302 	args->tmpp = NULL;
5303 	args->to_free = NULL;
5304 	args->ops = args->iops;
5305 	args->rqstp = rqstp;
5306 
5307 	return !nfsd4_decode_compound(args);
5308 }
5309 
5310 int
5311 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p)
5312 {
5313 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
5314 	struct xdr_buf *buf = resp->xdr.buf;
5315 
5316 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
5317 				 buf->tail[0].iov_len);
5318 
5319 	*p = resp->cstate.status;
5320 
5321 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
5322 
5323 	p = resp->tagp;
5324 	*p++ = htonl(resp->taglen);
5325 	memcpy(p, resp->tag, resp->taglen);
5326 	p += XDR_QUADLEN(resp->taglen);
5327 	*p++ = htonl(resp->opcnt);
5328 
5329 	nfsd4_sequence_done(resp);
5330 	return 1;
5331 }
5332 
5333 /*
5334  * Local variables:
5335  *  c-basic-offset: 8
5336  * End:
5337  */
5338