xref: /linux/fs/nfsd/nfs4xdr.c (revision 9a4e47ef98a3041f6d2869ba2cd3401701776275)
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 <linux/vmalloc.h>
46 
47 #include <uapi/linux/xattr.h>
48 
49 #include "idmap.h"
50 #include "acl.h"
51 #include "xdr4.h"
52 #include "vfs.h"
53 #include "state.h"
54 #include "cache.h"
55 #include "netns.h"
56 #include "pnfs.h"
57 #include "filecache.h"
58 
59 #include "trace.h"
60 
61 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
62 #include <linux/security.h>
63 #endif
64 
65 
66 #define NFSDDBG_FACILITY		NFSDDBG_XDR
67 
68 const u32 nfsd_suppattrs[3][3] = {
69 	{NFSD4_SUPPORTED_ATTRS_WORD0,
70 	 NFSD4_SUPPORTED_ATTRS_WORD1,
71 	 NFSD4_SUPPORTED_ATTRS_WORD2},
72 
73 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
74 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
75 	 NFSD4_1_SUPPORTED_ATTRS_WORD2},
76 
77 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
78 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
79 	 NFSD4_2_SUPPORTED_ATTRS_WORD2},
80 };
81 
82 /*
83  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
84  * directory in order to indicate to the client that a filesystem boundary is present
85  * We use a fixed fsid for a referral
86  */
87 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
88 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
89 
90 static __be32
91 check_filename(char *str, int len)
92 {
93 	int i;
94 
95 	if (len == 0)
96 		return nfserr_inval;
97 	if (len > NFS4_MAXNAMLEN)
98 		return nfserr_nametoolong;
99 	if (isdotent(str, len))
100 		return nfserr_badname;
101 	for (i = 0; i < len; i++)
102 		if (str[i] == '/')
103 			return nfserr_badname;
104 	return 0;
105 }
106 
107 static int zero_clientid(clientid_t *clid)
108 {
109 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
110 }
111 
112 /**
113  * svcxdr_tmpalloc - allocate memory to be freed after compound processing
114  * @argp: NFSv4 compound argument structure
115  * @len: length of buffer to allocate
116  *
117  * Allocates a buffer of size @len to be freed when processing the compound
118  * operation described in @argp finishes.
119  */
120 static void *
121 svcxdr_tmpalloc(struct nfsd4_compoundargs *argp, u32 len)
122 {
123 	struct svcxdr_tmpbuf *tb;
124 
125 	tb = kmalloc(sizeof(*tb) + len, GFP_KERNEL);
126 	if (!tb)
127 		return NULL;
128 	tb->next = argp->to_free;
129 	argp->to_free = tb;
130 	return tb->buf;
131 }
132 
133 /*
134  * For xdr strings that need to be passed to other kernel api's
135  * as null-terminated strings.
136  *
137  * Note null-terminating in place usually isn't safe since the
138  * buffer might end on a page boundary.
139  */
140 static char *
141 svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len)
142 {
143 	char *p = svcxdr_tmpalloc(argp, len + 1);
144 
145 	if (!p)
146 		return NULL;
147 	memcpy(p, buf, len);
148 	p[len] = '\0';
149 	return p;
150 }
151 
152 static void *
153 svcxdr_savemem(struct nfsd4_compoundargs *argp, __be32 *p, u32 len)
154 {
155 	__be32 *tmp;
156 
157 	/*
158 	 * The location of the decoded data item is stable,
159 	 * so @p is OK to use. This is the common case.
160 	 */
161 	if (p != argp->xdr->scratch.iov_base)
162 		return p;
163 
164 	tmp = svcxdr_tmpalloc(argp, len);
165 	if (!tmp)
166 		return NULL;
167 	memcpy(tmp, p, len);
168 	return tmp;
169 }
170 
171 /*
172  * NFSv4 basic data type decoders
173  */
174 
175 /*
176  * This helper handles variable-length opaques which belong to protocol
177  * elements that this implementation does not support.
178  */
179 static __be32
180 nfsd4_decode_ignored_string(struct nfsd4_compoundargs *argp, u32 maxlen)
181 {
182 	u32 len;
183 
184 	if (xdr_stream_decode_u32(argp->xdr, &len) < 0)
185 		return nfserr_bad_xdr;
186 	if (maxlen && len > maxlen)
187 		return nfserr_bad_xdr;
188 	if (!xdr_inline_decode(argp->xdr, len))
189 		return nfserr_bad_xdr;
190 
191 	return nfs_ok;
192 }
193 
194 static __be32
195 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
196 {
197 	__be32 *p;
198 	u32 len;
199 
200 	if (xdr_stream_decode_u32(argp->xdr, &len) < 0)
201 		return nfserr_bad_xdr;
202 	if (len == 0 || len > NFS4_OPAQUE_LIMIT)
203 		return nfserr_bad_xdr;
204 	p = xdr_inline_decode(argp->xdr, len);
205 	if (!p)
206 		return nfserr_bad_xdr;
207 	o->data = svcxdr_savemem(argp, p, len);
208 	if (!o->data)
209 		return nfserr_jukebox;
210 	o->len = len;
211 
212 	return nfs_ok;
213 }
214 
215 static __be32
216 nfsd4_decode_component4(struct nfsd4_compoundargs *argp, char **namp, u32 *lenp)
217 {
218 	__be32 *p, status;
219 
220 	if (xdr_stream_decode_u32(argp->xdr, lenp) < 0)
221 		return nfserr_bad_xdr;
222 	p = xdr_inline_decode(argp->xdr, *lenp);
223 	if (!p)
224 		return nfserr_bad_xdr;
225 	status = check_filename((char *)p, *lenp);
226 	if (status)
227 		return status;
228 	*namp = svcxdr_savemem(argp, p, *lenp);
229 	if (!*namp)
230 		return nfserr_jukebox;
231 
232 	return nfs_ok;
233 }
234 
235 static __be32
236 nfsd4_decode_nfstime4(struct nfsd4_compoundargs *argp, struct timespec64 *tv)
237 {
238 	__be32 *p;
239 
240 	p = xdr_inline_decode(argp->xdr, XDR_UNIT * 3);
241 	if (!p)
242 		return nfserr_bad_xdr;
243 	p = xdr_decode_hyper(p, &tv->tv_sec);
244 	tv->tv_nsec = be32_to_cpup(p++);
245 	if (tv->tv_nsec >= (u32)1000000000)
246 		return nfserr_inval;
247 	return nfs_ok;
248 }
249 
250 static __be32
251 nfsd4_decode_verifier4(struct nfsd4_compoundargs *argp, nfs4_verifier *verf)
252 {
253 	__be32 *p;
254 
255 	p = xdr_inline_decode(argp->xdr, NFS4_VERIFIER_SIZE);
256 	if (!p)
257 		return nfserr_bad_xdr;
258 	memcpy(verf->data, p, sizeof(verf->data));
259 	return nfs_ok;
260 }
261 
262 /**
263  * nfsd4_decode_bitmap4 - Decode an NFSv4 bitmap4
264  * @argp: NFSv4 compound argument structure
265  * @bmval: pointer to an array of u32's to decode into
266  * @bmlen: size of the @bmval array
267  *
268  * The server needs to return nfs_ok rather than nfserr_bad_xdr when
269  * encountering bitmaps containing bits it does not recognize. This
270  * includes bits in bitmap words past WORDn, where WORDn is the last
271  * bitmap WORD the implementation currently supports. Thus we are
272  * careful here to simply ignore bits in bitmap words that this
273  * implementation has yet to support explicitly.
274  *
275  * Return values:
276  *   %nfs_ok: @bmval populated successfully
277  *   %nfserr_bad_xdr: the encoded bitmap was invalid
278  */
279 static __be32
280 nfsd4_decode_bitmap4(struct nfsd4_compoundargs *argp, u32 *bmval, u32 bmlen)
281 {
282 	ssize_t status;
283 
284 	status = xdr_stream_decode_uint32_array(argp->xdr, bmval, bmlen);
285 	return status == -EBADMSG ? nfserr_bad_xdr : nfs_ok;
286 }
287 
288 static __be32
289 nfsd4_decode_nfsace4(struct nfsd4_compoundargs *argp, struct nfs4_ace *ace)
290 {
291 	__be32 *p, status;
292 	u32 length;
293 
294 	if (xdr_stream_decode_u32(argp->xdr, &ace->type) < 0)
295 		return nfserr_bad_xdr;
296 	if (xdr_stream_decode_u32(argp->xdr, &ace->flag) < 0)
297 		return nfserr_bad_xdr;
298 	if (xdr_stream_decode_u32(argp->xdr, &ace->access_mask) < 0)
299 		return nfserr_bad_xdr;
300 
301 	if (xdr_stream_decode_u32(argp->xdr, &length) < 0)
302 		return nfserr_bad_xdr;
303 	p = xdr_inline_decode(argp->xdr, length);
304 	if (!p)
305 		return nfserr_bad_xdr;
306 	ace->whotype = nfs4_acl_get_whotype((char *)p, length);
307 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
308 		status = nfs_ok;
309 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
310 		status = nfsd_map_name_to_gid(argp->rqstp,
311 				(char *)p, length, &ace->who_gid);
312 	else
313 		status = nfsd_map_name_to_uid(argp->rqstp,
314 				(char *)p, length, &ace->who_uid);
315 
316 	return status;
317 }
318 
319 /* A counted array of nfsace4's */
320 static noinline __be32
321 nfsd4_decode_acl(struct nfsd4_compoundargs *argp, struct nfs4_acl **acl)
322 {
323 	struct nfs4_ace *ace;
324 	__be32 status;
325 	u32 count;
326 
327 	if (xdr_stream_decode_u32(argp->xdr, &count) < 0)
328 		return nfserr_bad_xdr;
329 
330 	if (count > xdr_stream_remaining(argp->xdr) / 20)
331 		/*
332 		 * Even with 4-byte names there wouldn't be
333 		 * space for that many aces; something fishy is
334 		 * going on:
335 		 */
336 		return nfserr_fbig;
337 
338 	*acl = svcxdr_tmpalloc(argp, nfs4_acl_bytes(count));
339 	if (*acl == NULL)
340 		return nfserr_jukebox;
341 
342 	(*acl)->naces = count;
343 	for (ace = (*acl)->aces; ace < (*acl)->aces + count; ace++) {
344 		status = nfsd4_decode_nfsace4(argp, ace);
345 		if (status)
346 			return status;
347 	}
348 
349 	return nfs_ok;
350 }
351 
352 static noinline __be32
353 nfsd4_decode_security_label(struct nfsd4_compoundargs *argp,
354 			    struct xdr_netobj *label)
355 {
356 	u32 lfs, pi, length;
357 	__be32 *p;
358 
359 	if (xdr_stream_decode_u32(argp->xdr, &lfs) < 0)
360 		return nfserr_bad_xdr;
361 	if (xdr_stream_decode_u32(argp->xdr, &pi) < 0)
362 		return nfserr_bad_xdr;
363 
364 	if (xdr_stream_decode_u32(argp->xdr, &length) < 0)
365 		return nfserr_bad_xdr;
366 	if (length > NFS4_MAXLABELLEN)
367 		return nfserr_badlabel;
368 	p = xdr_inline_decode(argp->xdr, length);
369 	if (!p)
370 		return nfserr_bad_xdr;
371 	label->len = length;
372 	label->data = svcxdr_dupstr(argp, p, length);
373 	if (!label->data)
374 		return nfserr_jukebox;
375 
376 	return nfs_ok;
377 }
378 
379 static __be32
380 nfsd4_decode_fattr4(struct nfsd4_compoundargs *argp, u32 *bmval, u32 bmlen,
381 		    struct iattr *iattr, struct nfs4_acl **acl,
382 		    struct xdr_netobj *label, int *umask)
383 {
384 	unsigned int starting_pos;
385 	u32 attrlist4_count;
386 	__be32 *p, status;
387 
388 	iattr->ia_valid = 0;
389 	status = nfsd4_decode_bitmap4(argp, bmval, bmlen);
390 	if (status)
391 		return nfserr_bad_xdr;
392 
393 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
394 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
395 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2) {
396 		if (nfsd_attrs_supported(argp->minorversion, bmval))
397 			return nfserr_inval;
398 		return nfserr_attrnotsupp;
399 	}
400 
401 	if (xdr_stream_decode_u32(argp->xdr, &attrlist4_count) < 0)
402 		return nfserr_bad_xdr;
403 	starting_pos = xdr_stream_pos(argp->xdr);
404 
405 	if (bmval[0] & FATTR4_WORD0_SIZE) {
406 		u64 size;
407 
408 		if (xdr_stream_decode_u64(argp->xdr, &size) < 0)
409 			return nfserr_bad_xdr;
410 		iattr->ia_size = size;
411 		iattr->ia_valid |= ATTR_SIZE;
412 	}
413 	if (bmval[0] & FATTR4_WORD0_ACL) {
414 		status = nfsd4_decode_acl(argp, acl);
415 		if (status)
416 			return status;
417 	} else
418 		*acl = NULL;
419 	if (bmval[1] & FATTR4_WORD1_MODE) {
420 		u32 mode;
421 
422 		if (xdr_stream_decode_u32(argp->xdr, &mode) < 0)
423 			return nfserr_bad_xdr;
424 		iattr->ia_mode = mode;
425 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
426 		iattr->ia_valid |= ATTR_MODE;
427 	}
428 	if (bmval[1] & FATTR4_WORD1_OWNER) {
429 		u32 length;
430 
431 		if (xdr_stream_decode_u32(argp->xdr, &length) < 0)
432 			return nfserr_bad_xdr;
433 		p = xdr_inline_decode(argp->xdr, length);
434 		if (!p)
435 			return nfserr_bad_xdr;
436 		status = nfsd_map_name_to_uid(argp->rqstp, (char *)p, length,
437 					      &iattr->ia_uid);
438 		if (status)
439 			return status;
440 		iattr->ia_valid |= ATTR_UID;
441 	}
442 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
443 		u32 length;
444 
445 		if (xdr_stream_decode_u32(argp->xdr, &length) < 0)
446 			return nfserr_bad_xdr;
447 		p = xdr_inline_decode(argp->xdr, length);
448 		if (!p)
449 			return nfserr_bad_xdr;
450 		status = nfsd_map_name_to_gid(argp->rqstp, (char *)p, length,
451 					      &iattr->ia_gid);
452 		if (status)
453 			return status;
454 		iattr->ia_valid |= ATTR_GID;
455 	}
456 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
457 		u32 set_it;
458 
459 		if (xdr_stream_decode_u32(argp->xdr, &set_it) < 0)
460 			return nfserr_bad_xdr;
461 		switch (set_it) {
462 		case NFS4_SET_TO_CLIENT_TIME:
463 			status = nfsd4_decode_nfstime4(argp, &iattr->ia_atime);
464 			if (status)
465 				return status;
466 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
467 			break;
468 		case NFS4_SET_TO_SERVER_TIME:
469 			iattr->ia_valid |= ATTR_ATIME;
470 			break;
471 		default:
472 			return nfserr_bad_xdr;
473 		}
474 	}
475 	if (bmval[1] & FATTR4_WORD1_TIME_CREATE) {
476 		struct timespec64 ts;
477 
478 		/* No Linux filesystem supports setting this attribute. */
479 		bmval[1] &= ~FATTR4_WORD1_TIME_CREATE;
480 		status = nfsd4_decode_nfstime4(argp, &ts);
481 		if (status)
482 			return status;
483 	}
484 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
485 		u32 set_it;
486 
487 		if (xdr_stream_decode_u32(argp->xdr, &set_it) < 0)
488 			return nfserr_bad_xdr;
489 		switch (set_it) {
490 		case NFS4_SET_TO_CLIENT_TIME:
491 			status = nfsd4_decode_nfstime4(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 			return nfserr_bad_xdr;
501 		}
502 	}
503 	label->len = 0;
504 	if (IS_ENABLED(CONFIG_NFSD_V4_SECURITY_LABEL) &&
505 	    bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
506 		status = nfsd4_decode_security_label(argp, label);
507 		if (status)
508 			return status;
509 	}
510 	if (bmval[2] & FATTR4_WORD2_MODE_UMASK) {
511 		u32 mode, mask;
512 
513 		if (!umask)
514 			return nfserr_bad_xdr;
515 		if (xdr_stream_decode_u32(argp->xdr, &mode) < 0)
516 			return nfserr_bad_xdr;
517 		iattr->ia_mode = mode & (S_IFMT | S_IALLUGO);
518 		if (xdr_stream_decode_u32(argp->xdr, &mask) < 0)
519 			return nfserr_bad_xdr;
520 		*umask = mask & S_IRWXUGO;
521 		iattr->ia_valid |= ATTR_MODE;
522 	}
523 
524 	/* request sanity: did attrlist4 contain the expected number of words? */
525 	if (attrlist4_count != xdr_stream_pos(argp->xdr) - starting_pos)
526 		return nfserr_bad_xdr;
527 
528 	return nfs_ok;
529 }
530 
531 static __be32
532 nfsd4_decode_stateid4(struct nfsd4_compoundargs *argp, stateid_t *sid)
533 {
534 	__be32 *p;
535 
536 	p = xdr_inline_decode(argp->xdr, NFS4_STATEID_SIZE);
537 	if (!p)
538 		return nfserr_bad_xdr;
539 	sid->si_generation = be32_to_cpup(p++);
540 	memcpy(&sid->si_opaque, p, sizeof(sid->si_opaque));
541 	return nfs_ok;
542 }
543 
544 static __be32
545 nfsd4_decode_clientid4(struct nfsd4_compoundargs *argp, clientid_t *clientid)
546 {
547 	__be32 *p;
548 
549 	p = xdr_inline_decode(argp->xdr, sizeof(__be64));
550 	if (!p)
551 		return nfserr_bad_xdr;
552 	memcpy(clientid, p, sizeof(*clientid));
553 	return nfs_ok;
554 }
555 
556 static __be32
557 nfsd4_decode_state_owner4(struct nfsd4_compoundargs *argp,
558 			  clientid_t *clientid, struct xdr_netobj *owner)
559 {
560 	__be32 status;
561 
562 	status = nfsd4_decode_clientid4(argp, clientid);
563 	if (status)
564 		return status;
565 	return nfsd4_decode_opaque(argp, owner);
566 }
567 
568 #ifdef CONFIG_NFSD_PNFS
569 static __be32
570 nfsd4_decode_deviceid4(struct nfsd4_compoundargs *argp,
571 		       struct nfsd4_deviceid *devid)
572 {
573 	__be32 *p;
574 
575 	p = xdr_inline_decode(argp->xdr, NFS4_DEVICEID4_SIZE);
576 	if (!p)
577 		return nfserr_bad_xdr;
578 	memcpy(devid, p, sizeof(*devid));
579 	return nfs_ok;
580 }
581 
582 static __be32
583 nfsd4_decode_layoutupdate4(struct nfsd4_compoundargs *argp,
584 			   struct nfsd4_layoutcommit *lcp)
585 {
586 	if (xdr_stream_decode_u32(argp->xdr, &lcp->lc_layout_type) < 0)
587 		return nfserr_bad_xdr;
588 	if (lcp->lc_layout_type < LAYOUT_NFSV4_1_FILES)
589 		return nfserr_bad_xdr;
590 	if (lcp->lc_layout_type >= LAYOUT_TYPE_MAX)
591 		return nfserr_bad_xdr;
592 
593 	if (xdr_stream_decode_u32(argp->xdr, &lcp->lc_up_len) < 0)
594 		return nfserr_bad_xdr;
595 	if (lcp->lc_up_len > 0) {
596 		lcp->lc_up_layout = xdr_inline_decode(argp->xdr, lcp->lc_up_len);
597 		if (!lcp->lc_up_layout)
598 			return nfserr_bad_xdr;
599 	}
600 
601 	return nfs_ok;
602 }
603 
604 static __be32
605 nfsd4_decode_layoutreturn4(struct nfsd4_compoundargs *argp,
606 			   struct nfsd4_layoutreturn *lrp)
607 {
608 	__be32 status;
609 
610 	if (xdr_stream_decode_u32(argp->xdr, &lrp->lr_return_type) < 0)
611 		return nfserr_bad_xdr;
612 	switch (lrp->lr_return_type) {
613 	case RETURN_FILE:
614 		if (xdr_stream_decode_u64(argp->xdr, &lrp->lr_seg.offset) < 0)
615 			return nfserr_bad_xdr;
616 		if (xdr_stream_decode_u64(argp->xdr, &lrp->lr_seg.length) < 0)
617 			return nfserr_bad_xdr;
618 		status = nfsd4_decode_stateid4(argp, &lrp->lr_sid);
619 		if (status)
620 			return status;
621 		if (xdr_stream_decode_u32(argp->xdr, &lrp->lrf_body_len) < 0)
622 			return nfserr_bad_xdr;
623 		if (lrp->lrf_body_len > 0) {
624 			lrp->lrf_body = xdr_inline_decode(argp->xdr, lrp->lrf_body_len);
625 			if (!lrp->lrf_body)
626 				return nfserr_bad_xdr;
627 		}
628 		break;
629 	case RETURN_FSID:
630 	case RETURN_ALL:
631 		lrp->lr_seg.offset = 0;
632 		lrp->lr_seg.length = NFS4_MAX_UINT64;
633 		break;
634 	default:
635 		return nfserr_bad_xdr;
636 	}
637 
638 	return nfs_ok;
639 }
640 
641 #endif /* CONFIG_NFSD_PNFS */
642 
643 static __be32
644 nfsd4_decode_sessionid4(struct nfsd4_compoundargs *argp,
645 			struct nfs4_sessionid *sessionid)
646 {
647 	__be32 *p;
648 
649 	p = xdr_inline_decode(argp->xdr, NFS4_MAX_SESSIONID_LEN);
650 	if (!p)
651 		return nfserr_bad_xdr;
652 	memcpy(sessionid->data, p, sizeof(sessionid->data));
653 	return nfs_ok;
654 }
655 
656 /* Defined in Appendix A of RFC 5531 */
657 static __be32
658 nfsd4_decode_authsys_parms(struct nfsd4_compoundargs *argp,
659 			   struct nfsd4_cb_sec *cbs)
660 {
661 	u32 stamp, gidcount, uid, gid;
662 	__be32 *p, status;
663 
664 	if (xdr_stream_decode_u32(argp->xdr, &stamp) < 0)
665 		return nfserr_bad_xdr;
666 	/* machine name */
667 	status = nfsd4_decode_ignored_string(argp, 255);
668 	if (status)
669 		return status;
670 	if (xdr_stream_decode_u32(argp->xdr, &uid) < 0)
671 		return nfserr_bad_xdr;
672 	if (xdr_stream_decode_u32(argp->xdr, &gid) < 0)
673 		return nfserr_bad_xdr;
674 	if (xdr_stream_decode_u32(argp->xdr, &gidcount) < 0)
675 		return nfserr_bad_xdr;
676 	if (gidcount > 16)
677 		return nfserr_bad_xdr;
678 	p = xdr_inline_decode(argp->xdr, gidcount << 2);
679 	if (!p)
680 		return nfserr_bad_xdr;
681 	if (cbs->flavor == (u32)(-1)) {
682 		struct user_namespace *userns = nfsd_user_namespace(argp->rqstp);
683 
684 		kuid_t kuid = make_kuid(userns, uid);
685 		kgid_t kgid = make_kgid(userns, gid);
686 		if (uid_valid(kuid) && gid_valid(kgid)) {
687 			cbs->uid = kuid;
688 			cbs->gid = kgid;
689 			cbs->flavor = RPC_AUTH_UNIX;
690 		} else {
691 			dprintk("RPC_AUTH_UNIX with invalid uid or gid, ignoring!\n");
692 		}
693 	}
694 
695 	return nfs_ok;
696 }
697 
698 static __be32
699 nfsd4_decode_gss_cb_handles4(struct nfsd4_compoundargs *argp,
700 			     struct nfsd4_cb_sec *cbs)
701 {
702 	__be32 status;
703 	u32 service;
704 
705 	dprintk("RPC_AUTH_GSS callback secflavor not supported!\n");
706 
707 	if (xdr_stream_decode_u32(argp->xdr, &service) < 0)
708 		return nfserr_bad_xdr;
709 	if (service < RPC_GSS_SVC_NONE || service > RPC_GSS_SVC_PRIVACY)
710 		return nfserr_bad_xdr;
711 	/* gcbp_handle_from_server */
712 	status = nfsd4_decode_ignored_string(argp, 0);
713 	if (status)
714 		return status;
715 	/* gcbp_handle_from_client */
716 	status = nfsd4_decode_ignored_string(argp, 0);
717 	if (status)
718 		return status;
719 
720 	return nfs_ok;
721 }
722 
723 /* a counted array of callback_sec_parms4 items */
724 static __be32
725 nfsd4_decode_cb_sec(struct nfsd4_compoundargs *argp, struct nfsd4_cb_sec *cbs)
726 {
727 	u32 i, secflavor, nr_secflavs;
728 	__be32 status;
729 
730 	/* callback_sec_params4 */
731 	if (xdr_stream_decode_u32(argp->xdr, &nr_secflavs) < 0)
732 		return nfserr_bad_xdr;
733 	if (nr_secflavs)
734 		cbs->flavor = (u32)(-1);
735 	else
736 		/* Is this legal? Be generous, take it to mean AUTH_NONE: */
737 		cbs->flavor = 0;
738 
739 	for (i = 0; i < nr_secflavs; ++i) {
740 		if (xdr_stream_decode_u32(argp->xdr, &secflavor) < 0)
741 			return nfserr_bad_xdr;
742 		switch (secflavor) {
743 		case RPC_AUTH_NULL:
744 			/* void */
745 			if (cbs->flavor == (u32)(-1))
746 				cbs->flavor = RPC_AUTH_NULL;
747 			break;
748 		case RPC_AUTH_UNIX:
749 			status = nfsd4_decode_authsys_parms(argp, cbs);
750 			if (status)
751 				return status;
752 			break;
753 		case RPC_AUTH_GSS:
754 			status = nfsd4_decode_gss_cb_handles4(argp, cbs);
755 			if (status)
756 				return status;
757 			break;
758 		default:
759 			return nfserr_inval;
760 		}
761 	}
762 
763 	return nfs_ok;
764 }
765 
766 
767 /*
768  * NFSv4 operation argument decoders
769  */
770 
771 static __be32
772 nfsd4_decode_access(struct nfsd4_compoundargs *argp,
773 		    union nfsd4_op_u *u)
774 {
775 	struct nfsd4_access *access = &u->access;
776 	if (xdr_stream_decode_u32(argp->xdr, &access->ac_req_access) < 0)
777 		return nfserr_bad_xdr;
778 	return nfs_ok;
779 }
780 
781 static __be32
782 nfsd4_decode_close(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
783 {
784 	struct nfsd4_close *close = &u->close;
785 	if (xdr_stream_decode_u32(argp->xdr, &close->cl_seqid) < 0)
786 		return nfserr_bad_xdr;
787 	return nfsd4_decode_stateid4(argp, &close->cl_stateid);
788 }
789 
790 
791 static __be32
792 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
793 {
794 	struct nfsd4_commit *commit = &u->commit;
795 	if (xdr_stream_decode_u64(argp->xdr, &commit->co_offset) < 0)
796 		return nfserr_bad_xdr;
797 	if (xdr_stream_decode_u32(argp->xdr, &commit->co_count) < 0)
798 		return nfserr_bad_xdr;
799 	memset(&commit->co_verf, 0, sizeof(commit->co_verf));
800 	return nfs_ok;
801 }
802 
803 static __be32
804 nfsd4_decode_create(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
805 {
806 	struct nfsd4_create *create = &u->create;
807 	__be32 *p, status;
808 
809 	memset(create, 0, sizeof(*create));
810 	if (xdr_stream_decode_u32(argp->xdr, &create->cr_type) < 0)
811 		return nfserr_bad_xdr;
812 	switch (create->cr_type) {
813 	case NF4LNK:
814 		if (xdr_stream_decode_u32(argp->xdr, &create->cr_datalen) < 0)
815 			return nfserr_bad_xdr;
816 		p = xdr_inline_decode(argp->xdr, create->cr_datalen);
817 		if (!p)
818 			return nfserr_bad_xdr;
819 		create->cr_data = svcxdr_dupstr(argp, p, create->cr_datalen);
820 		if (!create->cr_data)
821 			return nfserr_jukebox;
822 		break;
823 	case NF4BLK:
824 	case NF4CHR:
825 		if (xdr_stream_decode_u32(argp->xdr, &create->cr_specdata1) < 0)
826 			return nfserr_bad_xdr;
827 		if (xdr_stream_decode_u32(argp->xdr, &create->cr_specdata2) < 0)
828 			return nfserr_bad_xdr;
829 		break;
830 	case NF4SOCK:
831 	case NF4FIFO:
832 	case NF4DIR:
833 	default:
834 		break;
835 	}
836 	status = nfsd4_decode_component4(argp, &create->cr_name,
837 					 &create->cr_namelen);
838 	if (status)
839 		return status;
840 	status = nfsd4_decode_fattr4(argp, create->cr_bmval,
841 				    ARRAY_SIZE(create->cr_bmval),
842 				    &create->cr_iattr, &create->cr_acl,
843 				    &create->cr_label, &create->cr_umask);
844 	if (status)
845 		return status;
846 
847 	return nfs_ok;
848 }
849 
850 static inline __be32
851 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
852 {
853 	struct nfsd4_delegreturn *dr = &u->delegreturn;
854 	return nfsd4_decode_stateid4(argp, &dr->dr_stateid);
855 }
856 
857 static inline __be32
858 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
859 {
860 	struct nfsd4_getattr *getattr = &u->getattr;
861 	memset(getattr, 0, sizeof(*getattr));
862 	return nfsd4_decode_bitmap4(argp, getattr->ga_bmval,
863 				    ARRAY_SIZE(getattr->ga_bmval));
864 }
865 
866 static __be32
867 nfsd4_decode_link(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
868 {
869 	struct nfsd4_link *link = &u->link;
870 	memset(link, 0, sizeof(*link));
871 	return nfsd4_decode_component4(argp, &link->li_name, &link->li_namelen);
872 }
873 
874 static __be32
875 nfsd4_decode_open_to_lock_owner4(struct nfsd4_compoundargs *argp,
876 				 struct nfsd4_lock *lock)
877 {
878 	__be32 status;
879 
880 	if (xdr_stream_decode_u32(argp->xdr, &lock->lk_new_open_seqid) < 0)
881 		return nfserr_bad_xdr;
882 	status = nfsd4_decode_stateid4(argp, &lock->lk_new_open_stateid);
883 	if (status)
884 		return status;
885 	if (xdr_stream_decode_u32(argp->xdr, &lock->lk_new_lock_seqid) < 0)
886 		return nfserr_bad_xdr;
887 	return nfsd4_decode_state_owner4(argp, &lock->lk_new_clientid,
888 					 &lock->lk_new_owner);
889 }
890 
891 static __be32
892 nfsd4_decode_exist_lock_owner4(struct nfsd4_compoundargs *argp,
893 			       struct nfsd4_lock *lock)
894 {
895 	__be32 status;
896 
897 	status = nfsd4_decode_stateid4(argp, &lock->lk_old_lock_stateid);
898 	if (status)
899 		return status;
900 	if (xdr_stream_decode_u32(argp->xdr, &lock->lk_old_lock_seqid) < 0)
901 		return nfserr_bad_xdr;
902 
903 	return nfs_ok;
904 }
905 
906 static __be32
907 nfsd4_decode_locker4(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
908 {
909 	if (xdr_stream_decode_bool(argp->xdr, &lock->lk_is_new) < 0)
910 		return nfserr_bad_xdr;
911 	if (lock->lk_is_new)
912 		return nfsd4_decode_open_to_lock_owner4(argp, lock);
913 	return nfsd4_decode_exist_lock_owner4(argp, lock);
914 }
915 
916 static __be32
917 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
918 {
919 	struct nfsd4_lock *lock = &u->lock;
920 	memset(lock, 0, sizeof(*lock));
921 	if (xdr_stream_decode_u32(argp->xdr, &lock->lk_type) < 0)
922 		return nfserr_bad_xdr;
923 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
924 		return nfserr_bad_xdr;
925 	if (xdr_stream_decode_bool(argp->xdr, &lock->lk_reclaim) < 0)
926 		return nfserr_bad_xdr;
927 	if (xdr_stream_decode_u64(argp->xdr, &lock->lk_offset) < 0)
928 		return nfserr_bad_xdr;
929 	if (xdr_stream_decode_u64(argp->xdr, &lock->lk_length) < 0)
930 		return nfserr_bad_xdr;
931 	return nfsd4_decode_locker4(argp, lock);
932 }
933 
934 static __be32
935 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
936 {
937 	struct nfsd4_lockt *lockt = &u->lockt;
938 	memset(lockt, 0, sizeof(*lockt));
939 	if (xdr_stream_decode_u32(argp->xdr, &lockt->lt_type) < 0)
940 		return nfserr_bad_xdr;
941 	if ((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
942 		return nfserr_bad_xdr;
943 	if (xdr_stream_decode_u64(argp->xdr, &lockt->lt_offset) < 0)
944 		return nfserr_bad_xdr;
945 	if (xdr_stream_decode_u64(argp->xdr, &lockt->lt_length) < 0)
946 		return nfserr_bad_xdr;
947 	return nfsd4_decode_state_owner4(argp, &lockt->lt_clientid,
948 					 &lockt->lt_owner);
949 }
950 
951 static __be32
952 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
953 {
954 	struct nfsd4_locku *locku = &u->locku;
955 	__be32 status;
956 
957 	if (xdr_stream_decode_u32(argp->xdr, &locku->lu_type) < 0)
958 		return nfserr_bad_xdr;
959 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
960 		return nfserr_bad_xdr;
961 	if (xdr_stream_decode_u32(argp->xdr, &locku->lu_seqid) < 0)
962 		return nfserr_bad_xdr;
963 	status = nfsd4_decode_stateid4(argp, &locku->lu_stateid);
964 	if (status)
965 		return status;
966 	if (xdr_stream_decode_u64(argp->xdr, &locku->lu_offset) < 0)
967 		return nfserr_bad_xdr;
968 	if (xdr_stream_decode_u64(argp->xdr, &locku->lu_length) < 0)
969 		return nfserr_bad_xdr;
970 
971 	return nfs_ok;
972 }
973 
974 static __be32
975 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
976 {
977 	struct nfsd4_lookup *lookup = &u->lookup;
978 	return nfsd4_decode_component4(argp, &lookup->lo_name, &lookup->lo_len);
979 }
980 
981 static __be32
982 nfsd4_decode_createhow4(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
983 {
984 	__be32 status;
985 
986 	if (xdr_stream_decode_u32(argp->xdr, &open->op_createmode) < 0)
987 		return nfserr_bad_xdr;
988 	switch (open->op_createmode) {
989 	case NFS4_CREATE_UNCHECKED:
990 	case NFS4_CREATE_GUARDED:
991 		status = nfsd4_decode_fattr4(argp, open->op_bmval,
992 					     ARRAY_SIZE(open->op_bmval),
993 					     &open->op_iattr, &open->op_acl,
994 					     &open->op_label, &open->op_umask);
995 		if (status)
996 			return status;
997 		break;
998 	case NFS4_CREATE_EXCLUSIVE:
999 		status = nfsd4_decode_verifier4(argp, &open->op_verf);
1000 		if (status)
1001 			return status;
1002 		break;
1003 	case NFS4_CREATE_EXCLUSIVE4_1:
1004 		if (argp->minorversion < 1)
1005 			return nfserr_bad_xdr;
1006 		status = nfsd4_decode_verifier4(argp, &open->op_verf);
1007 		if (status)
1008 			return status;
1009 		status = nfsd4_decode_fattr4(argp, open->op_bmval,
1010 					     ARRAY_SIZE(open->op_bmval),
1011 					     &open->op_iattr, &open->op_acl,
1012 					     &open->op_label, &open->op_umask);
1013 		if (status)
1014 			return status;
1015 		break;
1016 	default:
1017 		return nfserr_bad_xdr;
1018 	}
1019 
1020 	return nfs_ok;
1021 }
1022 
1023 static __be32
1024 nfsd4_decode_openflag4(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
1025 {
1026 	__be32 status;
1027 
1028 	if (xdr_stream_decode_u32(argp->xdr, &open->op_create) < 0)
1029 		return nfserr_bad_xdr;
1030 	switch (open->op_create) {
1031 	case NFS4_OPEN_NOCREATE:
1032 		break;
1033 	case NFS4_OPEN_CREATE:
1034 		status = nfsd4_decode_createhow4(argp, open);
1035 		if (status)
1036 			return status;
1037 		break;
1038 	default:
1039 		return nfserr_bad_xdr;
1040 	}
1041 
1042 	return nfs_ok;
1043 }
1044 
1045 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
1046 {
1047 	u32 w;
1048 
1049 	if (xdr_stream_decode_u32(argp->xdr, &w) < 0)
1050 		return nfserr_bad_xdr;
1051 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
1052 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
1053 	if (deleg_when)
1054 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
1055 
1056 	switch (w & NFS4_SHARE_ACCESS_MASK) {
1057 	case NFS4_SHARE_ACCESS_READ:
1058 	case NFS4_SHARE_ACCESS_WRITE:
1059 	case NFS4_SHARE_ACCESS_BOTH:
1060 		break;
1061 	default:
1062 		return nfserr_bad_xdr;
1063 	}
1064 	w &= ~NFS4_SHARE_ACCESS_MASK;
1065 	if (!w)
1066 		return nfs_ok;
1067 	if (!argp->minorversion)
1068 		return nfserr_bad_xdr;
1069 	switch (w & NFS4_SHARE_WANT_MASK) {
1070 	case NFS4_SHARE_WANT_NO_PREFERENCE:
1071 	case NFS4_SHARE_WANT_READ_DELEG:
1072 	case NFS4_SHARE_WANT_WRITE_DELEG:
1073 	case NFS4_SHARE_WANT_ANY_DELEG:
1074 	case NFS4_SHARE_WANT_NO_DELEG:
1075 	case NFS4_SHARE_WANT_CANCEL:
1076 		break;
1077 	default:
1078 		return nfserr_bad_xdr;
1079 	}
1080 	w &= ~NFS4_SHARE_WANT_MASK;
1081 	if (!w)
1082 		return nfs_ok;
1083 
1084 	if (!deleg_when)	/* open_downgrade */
1085 		return nfserr_inval;
1086 	switch (w) {
1087 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
1088 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
1089 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
1090 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
1091 		return nfs_ok;
1092 	}
1093 	return nfserr_bad_xdr;
1094 }
1095 
1096 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
1097 {
1098 	if (xdr_stream_decode_u32(argp->xdr, x) < 0)
1099 		return nfserr_bad_xdr;
1100 	/* Note: unlike access bits, deny bits may be zero. */
1101 	if (*x & ~NFS4_SHARE_DENY_BOTH)
1102 		return nfserr_bad_xdr;
1103 
1104 	return nfs_ok;
1105 }
1106 
1107 static __be32
1108 nfsd4_decode_open_claim4(struct nfsd4_compoundargs *argp,
1109 			 struct nfsd4_open *open)
1110 {
1111 	__be32 status;
1112 
1113 	if (xdr_stream_decode_u32(argp->xdr, &open->op_claim_type) < 0)
1114 		return nfserr_bad_xdr;
1115 	switch (open->op_claim_type) {
1116 	case NFS4_OPEN_CLAIM_NULL:
1117 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
1118 		status = nfsd4_decode_component4(argp, &open->op_fname,
1119 						 &open->op_fnamelen);
1120 		if (status)
1121 			return status;
1122 		break;
1123 	case NFS4_OPEN_CLAIM_PREVIOUS:
1124 		if (xdr_stream_decode_u32(argp->xdr, &open->op_delegate_type) < 0)
1125 			return nfserr_bad_xdr;
1126 		break;
1127 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
1128 		status = nfsd4_decode_stateid4(argp, &open->op_delegate_stateid);
1129 		if (status)
1130 			return status;
1131 		status = nfsd4_decode_component4(argp, &open->op_fname,
1132 						 &open->op_fnamelen);
1133 		if (status)
1134 			return status;
1135 		break;
1136 	case NFS4_OPEN_CLAIM_FH:
1137 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
1138 		if (argp->minorversion < 1)
1139 			return nfserr_bad_xdr;
1140 		/* void */
1141 		break;
1142 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
1143 		if (argp->minorversion < 1)
1144 			return nfserr_bad_xdr;
1145 		status = nfsd4_decode_stateid4(argp, &open->op_delegate_stateid);
1146 		if (status)
1147 			return status;
1148 		break;
1149 	default:
1150 		return nfserr_bad_xdr;
1151 	}
1152 
1153 	return nfs_ok;
1154 }
1155 
1156 static __be32
1157 nfsd4_decode_open(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
1158 {
1159 	struct nfsd4_open *open = &u->open;
1160 	__be32 status;
1161 	u32 dummy;
1162 
1163 	memset(open, 0, sizeof(*open));
1164 
1165 	if (xdr_stream_decode_u32(argp->xdr, &open->op_seqid) < 0)
1166 		return nfserr_bad_xdr;
1167 	/* deleg_want is ignored */
1168 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
1169 					   &open->op_deleg_want, &dummy);
1170 	if (status)
1171 		return status;
1172 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
1173 	if (status)
1174 		return status;
1175 	status = nfsd4_decode_state_owner4(argp, &open->op_clientid,
1176 					   &open->op_owner);
1177 	if (status)
1178 		return status;
1179 	status = nfsd4_decode_openflag4(argp, open);
1180 	if (status)
1181 		return status;
1182 	return nfsd4_decode_open_claim4(argp, open);
1183 }
1184 
1185 static __be32
1186 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp,
1187 			  union nfsd4_op_u *u)
1188 {
1189 	struct nfsd4_open_confirm *open_conf = &u->open_confirm;
1190 	__be32 status;
1191 
1192 	if (argp->minorversion >= 1)
1193 		return nfserr_notsupp;
1194 
1195 	status = nfsd4_decode_stateid4(argp, &open_conf->oc_req_stateid);
1196 	if (status)
1197 		return status;
1198 	if (xdr_stream_decode_u32(argp->xdr, &open_conf->oc_seqid) < 0)
1199 		return nfserr_bad_xdr;
1200 
1201 	memset(&open_conf->oc_resp_stateid, 0,
1202 	       sizeof(open_conf->oc_resp_stateid));
1203 	return nfs_ok;
1204 }
1205 
1206 static __be32
1207 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp,
1208 			    union nfsd4_op_u *u)
1209 {
1210 	struct nfsd4_open_downgrade *open_down = &u->open_downgrade;
1211 	__be32 status;
1212 
1213 	memset(open_down, 0, sizeof(*open_down));
1214 	status = nfsd4_decode_stateid4(argp, &open_down->od_stateid);
1215 	if (status)
1216 		return status;
1217 	if (xdr_stream_decode_u32(argp->xdr, &open_down->od_seqid) < 0)
1218 		return nfserr_bad_xdr;
1219 	/* deleg_want is ignored */
1220 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
1221 					   &open_down->od_deleg_want, NULL);
1222 	if (status)
1223 		return status;
1224 	return nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
1225 }
1226 
1227 static __be32
1228 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
1229 {
1230 	struct nfsd4_putfh *putfh = &u->putfh;
1231 	__be32 *p;
1232 
1233 	if (xdr_stream_decode_u32(argp->xdr, &putfh->pf_fhlen) < 0)
1234 		return nfserr_bad_xdr;
1235 	if (putfh->pf_fhlen > NFS4_FHSIZE)
1236 		return nfserr_bad_xdr;
1237 	p = xdr_inline_decode(argp->xdr, putfh->pf_fhlen);
1238 	if (!p)
1239 		return nfserr_bad_xdr;
1240 	putfh->pf_fhval = svcxdr_savemem(argp, p, putfh->pf_fhlen);
1241 	if (!putfh->pf_fhval)
1242 		return nfserr_jukebox;
1243 
1244 	putfh->no_verify = false;
1245 	return nfs_ok;
1246 }
1247 
1248 static __be32
1249 nfsd4_decode_putpubfh(struct nfsd4_compoundargs *argp, union nfsd4_op_u *p)
1250 {
1251 	if (argp->minorversion == 0)
1252 		return nfs_ok;
1253 	return nfserr_notsupp;
1254 }
1255 
1256 static __be32
1257 nfsd4_decode_read(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
1258 {
1259 	struct nfsd4_read *read = &u->read;
1260 	__be32 status;
1261 
1262 	memset(read, 0, sizeof(*read));
1263 	status = nfsd4_decode_stateid4(argp, &read->rd_stateid);
1264 	if (status)
1265 		return status;
1266 	if (xdr_stream_decode_u64(argp->xdr, &read->rd_offset) < 0)
1267 		return nfserr_bad_xdr;
1268 	if (xdr_stream_decode_u32(argp->xdr, &read->rd_length) < 0)
1269 		return nfserr_bad_xdr;
1270 
1271 	return nfs_ok;
1272 }
1273 
1274 static __be32
1275 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
1276 {
1277 	struct nfsd4_readdir *readdir = &u->readdir;
1278 	__be32 status;
1279 
1280 	memset(readdir, 0, sizeof(*readdir));
1281 	if (xdr_stream_decode_u64(argp->xdr, &readdir->rd_cookie) < 0)
1282 		return nfserr_bad_xdr;
1283 	status = nfsd4_decode_verifier4(argp, &readdir->rd_verf);
1284 	if (status)
1285 		return status;
1286 	if (xdr_stream_decode_u32(argp->xdr, &readdir->rd_dircount) < 0)
1287 		return nfserr_bad_xdr;
1288 	if (xdr_stream_decode_u32(argp->xdr, &readdir->rd_maxcount) < 0)
1289 		return nfserr_bad_xdr;
1290 	if (xdr_stream_decode_uint32_array(argp->xdr, readdir->rd_bmval,
1291 					   ARRAY_SIZE(readdir->rd_bmval)) < 0)
1292 		return nfserr_bad_xdr;
1293 
1294 	return nfs_ok;
1295 }
1296 
1297 static __be32
1298 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
1299 {
1300 	struct nfsd4_remove *remove = &u->remove;
1301 	memset(&remove->rm_cinfo, 0, sizeof(remove->rm_cinfo));
1302 	return nfsd4_decode_component4(argp, &remove->rm_name, &remove->rm_namelen);
1303 }
1304 
1305 static __be32
1306 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
1307 {
1308 	struct nfsd4_rename *rename = &u->rename;
1309 	__be32 status;
1310 
1311 	memset(rename, 0, sizeof(*rename));
1312 	status = nfsd4_decode_component4(argp, &rename->rn_sname, &rename->rn_snamelen);
1313 	if (status)
1314 		return status;
1315 	return nfsd4_decode_component4(argp, &rename->rn_tname, &rename->rn_tnamelen);
1316 }
1317 
1318 static __be32
1319 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
1320 {
1321 	clientid_t *clientid = &u->renew;
1322 	return nfsd4_decode_clientid4(argp, clientid);
1323 }
1324 
1325 static __be32
1326 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1327 		     union nfsd4_op_u *u)
1328 {
1329 	struct nfsd4_secinfo *secinfo = &u->secinfo;
1330 	secinfo->si_exp = NULL;
1331 	return nfsd4_decode_component4(argp, &secinfo->si_name, &secinfo->si_namelen);
1332 }
1333 
1334 static __be32
1335 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
1336 {
1337 	struct nfsd4_setattr *setattr = &u->setattr;
1338 	__be32 status;
1339 
1340 	memset(setattr, 0, sizeof(*setattr));
1341 	status = nfsd4_decode_stateid4(argp, &setattr->sa_stateid);
1342 	if (status)
1343 		return status;
1344 	return nfsd4_decode_fattr4(argp, setattr->sa_bmval,
1345 				   ARRAY_SIZE(setattr->sa_bmval),
1346 				   &setattr->sa_iattr, &setattr->sa_acl,
1347 				   &setattr->sa_label, NULL);
1348 }
1349 
1350 static __be32
1351 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
1352 {
1353 	struct nfsd4_setclientid *setclientid = &u->setclientid;
1354 	__be32 *p, status;
1355 
1356 	memset(setclientid, 0, sizeof(*setclientid));
1357 
1358 	if (argp->minorversion >= 1)
1359 		return nfserr_notsupp;
1360 
1361 	status = nfsd4_decode_verifier4(argp, &setclientid->se_verf);
1362 	if (status)
1363 		return status;
1364 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1365 	if (status)
1366 		return status;
1367 	if (xdr_stream_decode_u32(argp->xdr, &setclientid->se_callback_prog) < 0)
1368 		return nfserr_bad_xdr;
1369 	if (xdr_stream_decode_u32(argp->xdr, &setclientid->se_callback_netid_len) < 0)
1370 		return nfserr_bad_xdr;
1371 	p = xdr_inline_decode(argp->xdr, setclientid->se_callback_netid_len);
1372 	if (!p)
1373 		return nfserr_bad_xdr;
1374 	setclientid->se_callback_netid_val = svcxdr_savemem(argp, p,
1375 						setclientid->se_callback_netid_len);
1376 	if (!setclientid->se_callback_netid_val)
1377 		return nfserr_jukebox;
1378 
1379 	if (xdr_stream_decode_u32(argp->xdr, &setclientid->se_callback_addr_len) < 0)
1380 		return nfserr_bad_xdr;
1381 	p = xdr_inline_decode(argp->xdr, setclientid->se_callback_addr_len);
1382 	if (!p)
1383 		return nfserr_bad_xdr;
1384 	setclientid->se_callback_addr_val = svcxdr_savemem(argp, p,
1385 						setclientid->se_callback_addr_len);
1386 	if (!setclientid->se_callback_addr_val)
1387 		return nfserr_jukebox;
1388 	if (xdr_stream_decode_u32(argp->xdr, &setclientid->se_callback_ident) < 0)
1389 		return nfserr_bad_xdr;
1390 
1391 	return nfs_ok;
1392 }
1393 
1394 static __be32
1395 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp,
1396 				 union nfsd4_op_u *u)
1397 {
1398 	struct nfsd4_setclientid_confirm *scd_c = &u->setclientid_confirm;
1399 	__be32 status;
1400 
1401 	if (argp->minorversion >= 1)
1402 		return nfserr_notsupp;
1403 
1404 	status = nfsd4_decode_clientid4(argp, &scd_c->sc_clientid);
1405 	if (status)
1406 		return status;
1407 	return nfsd4_decode_verifier4(argp, &scd_c->sc_confirm);
1408 }
1409 
1410 /* Also used for NVERIFY */
1411 static __be32
1412 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
1413 {
1414 	struct nfsd4_verify *verify = &u->verify;
1415 	__be32 *p, status;
1416 
1417 	memset(verify, 0, sizeof(*verify));
1418 
1419 	status = nfsd4_decode_bitmap4(argp, verify->ve_bmval,
1420 				      ARRAY_SIZE(verify->ve_bmval));
1421 	if (status)
1422 		return status;
1423 
1424 	/* For convenience's sake, we compare raw xdr'd attributes in
1425 	 * nfsd4_proc_verify */
1426 
1427 	if (xdr_stream_decode_u32(argp->xdr, &verify->ve_attrlen) < 0)
1428 		return nfserr_bad_xdr;
1429 	p = xdr_inline_decode(argp->xdr, verify->ve_attrlen);
1430 	if (!p)
1431 		return nfserr_bad_xdr;
1432 	verify->ve_attrval = svcxdr_savemem(argp, p, verify->ve_attrlen);
1433 	if (!verify->ve_attrval)
1434 		return nfserr_jukebox;
1435 
1436 	return nfs_ok;
1437 }
1438 
1439 static __be32
1440 nfsd4_decode_write(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
1441 {
1442 	struct nfsd4_write *write = &u->write;
1443 	__be32 status;
1444 
1445 	status = nfsd4_decode_stateid4(argp, &write->wr_stateid);
1446 	if (status)
1447 		return status;
1448 	if (xdr_stream_decode_u64(argp->xdr, &write->wr_offset) < 0)
1449 		return nfserr_bad_xdr;
1450 	if (xdr_stream_decode_u32(argp->xdr, &write->wr_stable_how) < 0)
1451 		return nfserr_bad_xdr;
1452 	if (write->wr_stable_how > NFS_FILE_SYNC)
1453 		return nfserr_bad_xdr;
1454 	if (xdr_stream_decode_u32(argp->xdr, &write->wr_buflen) < 0)
1455 		return nfserr_bad_xdr;
1456 	if (!xdr_stream_subsegment(argp->xdr, &write->wr_payload, write->wr_buflen))
1457 		return nfserr_bad_xdr;
1458 
1459 	write->wr_bytes_written = 0;
1460 	write->wr_how_written = 0;
1461 	memset(&write->wr_verifier, 0, sizeof(write->wr_verifier));
1462 	return nfs_ok;
1463 }
1464 
1465 static __be32
1466 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp,
1467 			       union nfsd4_op_u *u)
1468 {
1469 	struct nfsd4_release_lockowner *rlockowner = &u->release_lockowner;
1470 	__be32 status;
1471 
1472 	if (argp->minorversion >= 1)
1473 		return nfserr_notsupp;
1474 
1475 	status = nfsd4_decode_state_owner4(argp, &rlockowner->rl_clientid,
1476 					   &rlockowner->rl_owner);
1477 	if (status)
1478 		return status;
1479 
1480 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1481 		return nfserr_inval;
1482 
1483 	return nfs_ok;
1484 }
1485 
1486 static __be32 nfsd4_decode_backchannel_ctl(struct nfsd4_compoundargs *argp,
1487 					   union nfsd4_op_u *u)
1488 {
1489 	struct nfsd4_backchannel_ctl *bc = &u->backchannel_ctl;
1490 	memset(bc, 0, sizeof(*bc));
1491 	if (xdr_stream_decode_u32(argp->xdr, &bc->bc_cb_program) < 0)
1492 		return nfserr_bad_xdr;
1493 	return nfsd4_decode_cb_sec(argp, &bc->bc_cb_sec);
1494 }
1495 
1496 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp,
1497 						union nfsd4_op_u *u)
1498 {
1499 	struct nfsd4_bind_conn_to_session *bcts = &u->bind_conn_to_session;
1500 	u32 use_conn_in_rdma_mode;
1501 	__be32 status;
1502 
1503 	memset(bcts, 0, sizeof(*bcts));
1504 	status = nfsd4_decode_sessionid4(argp, &bcts->sessionid);
1505 	if (status)
1506 		return status;
1507 	if (xdr_stream_decode_u32(argp->xdr, &bcts->dir) < 0)
1508 		return nfserr_bad_xdr;
1509 	if (xdr_stream_decode_u32(argp->xdr, &use_conn_in_rdma_mode) < 0)
1510 		return nfserr_bad_xdr;
1511 
1512 	return nfs_ok;
1513 }
1514 
1515 static __be32
1516 nfsd4_decode_state_protect_ops(struct nfsd4_compoundargs *argp,
1517 			       struct nfsd4_exchange_id *exid)
1518 {
1519 	__be32 status;
1520 
1521 	status = nfsd4_decode_bitmap4(argp, exid->spo_must_enforce,
1522 				      ARRAY_SIZE(exid->spo_must_enforce));
1523 	if (status)
1524 		return nfserr_bad_xdr;
1525 	status = nfsd4_decode_bitmap4(argp, exid->spo_must_allow,
1526 				      ARRAY_SIZE(exid->spo_must_allow));
1527 	if (status)
1528 		return nfserr_bad_xdr;
1529 
1530 	return nfs_ok;
1531 }
1532 
1533 /*
1534  * This implementation currently does not support SP4_SSV.
1535  * This decoder simply skips over these arguments.
1536  */
1537 static noinline __be32
1538 nfsd4_decode_ssv_sp_parms(struct nfsd4_compoundargs *argp,
1539 			  struct nfsd4_exchange_id *exid)
1540 {
1541 	u32 count, window, num_gss_handles;
1542 	__be32 status;
1543 
1544 	/* ssp_ops */
1545 	status = nfsd4_decode_state_protect_ops(argp, exid);
1546 	if (status)
1547 		return status;
1548 
1549 	/* ssp_hash_algs<> */
1550 	if (xdr_stream_decode_u32(argp->xdr, &count) < 0)
1551 		return nfserr_bad_xdr;
1552 	while (count--) {
1553 		status = nfsd4_decode_ignored_string(argp, 0);
1554 		if (status)
1555 			return status;
1556 	}
1557 
1558 	/* ssp_encr_algs<> */
1559 	if (xdr_stream_decode_u32(argp->xdr, &count) < 0)
1560 		return nfserr_bad_xdr;
1561 	while (count--) {
1562 		status = nfsd4_decode_ignored_string(argp, 0);
1563 		if (status)
1564 			return status;
1565 	}
1566 
1567 	if (xdr_stream_decode_u32(argp->xdr, &window) < 0)
1568 		return nfserr_bad_xdr;
1569 	if (xdr_stream_decode_u32(argp->xdr, &num_gss_handles) < 0)
1570 		return nfserr_bad_xdr;
1571 
1572 	return nfs_ok;
1573 }
1574 
1575 static __be32
1576 nfsd4_decode_state_protect4_a(struct nfsd4_compoundargs *argp,
1577 			      struct nfsd4_exchange_id *exid)
1578 {
1579 	__be32 status;
1580 
1581 	if (xdr_stream_decode_u32(argp->xdr, &exid->spa_how) < 0)
1582 		return nfserr_bad_xdr;
1583 	switch (exid->spa_how) {
1584 	case SP4_NONE:
1585 		break;
1586 	case SP4_MACH_CRED:
1587 		status = nfsd4_decode_state_protect_ops(argp, exid);
1588 		if (status)
1589 			return status;
1590 		break;
1591 	case SP4_SSV:
1592 		status = nfsd4_decode_ssv_sp_parms(argp, exid);
1593 		if (status)
1594 			return status;
1595 		break;
1596 	default:
1597 		return nfserr_bad_xdr;
1598 	}
1599 
1600 	return nfs_ok;
1601 }
1602 
1603 static __be32
1604 nfsd4_decode_nfs_impl_id4(struct nfsd4_compoundargs *argp,
1605 			  struct nfsd4_exchange_id *exid)
1606 {
1607 	__be32 status;
1608 	u32 count;
1609 
1610 	if (xdr_stream_decode_u32(argp->xdr, &count) < 0)
1611 		return nfserr_bad_xdr;
1612 	switch (count) {
1613 	case 0:
1614 		break;
1615 	case 1:
1616 		/* Note that RFC 8881 places no length limit on
1617 		 * nii_domain, but this implementation permits no
1618 		 * more than NFS4_OPAQUE_LIMIT bytes */
1619 		status = nfsd4_decode_opaque(argp, &exid->nii_domain);
1620 		if (status)
1621 			return status;
1622 		/* Note that RFC 8881 places no length limit on
1623 		 * nii_name, but this implementation permits no
1624 		 * more than NFS4_OPAQUE_LIMIT bytes */
1625 		status = nfsd4_decode_opaque(argp, &exid->nii_name);
1626 		if (status)
1627 			return status;
1628 		status = nfsd4_decode_nfstime4(argp, &exid->nii_time);
1629 		if (status)
1630 			return status;
1631 		break;
1632 	default:
1633 		return nfserr_bad_xdr;
1634 	}
1635 
1636 	return nfs_ok;
1637 }
1638 
1639 static __be32
1640 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1641 			 union nfsd4_op_u *u)
1642 {
1643 	struct nfsd4_exchange_id *exid = &u->exchange_id;
1644 	__be32 status;
1645 
1646 	memset(exid, 0, sizeof(*exid));
1647 	status = nfsd4_decode_verifier4(argp, &exid->verifier);
1648 	if (status)
1649 		return status;
1650 	status = nfsd4_decode_opaque(argp, &exid->clname);
1651 	if (status)
1652 		return status;
1653 	if (xdr_stream_decode_u32(argp->xdr, &exid->flags) < 0)
1654 		return nfserr_bad_xdr;
1655 	status = nfsd4_decode_state_protect4_a(argp, exid);
1656 	if (status)
1657 		return status;
1658 	return nfsd4_decode_nfs_impl_id4(argp, exid);
1659 }
1660 
1661 static __be32
1662 nfsd4_decode_channel_attrs4(struct nfsd4_compoundargs *argp,
1663 			    struct nfsd4_channel_attrs *ca)
1664 {
1665 	__be32 *p;
1666 
1667 	p = xdr_inline_decode(argp->xdr, XDR_UNIT * 7);
1668 	if (!p)
1669 		return nfserr_bad_xdr;
1670 
1671 	/* headerpadsz is ignored */
1672 	p++;
1673 	ca->maxreq_sz = be32_to_cpup(p++);
1674 	ca->maxresp_sz = be32_to_cpup(p++);
1675 	ca->maxresp_cached = be32_to_cpup(p++);
1676 	ca->maxops = be32_to_cpup(p++);
1677 	ca->maxreqs = be32_to_cpup(p++);
1678 	ca->nr_rdma_attrs = be32_to_cpup(p);
1679 	switch (ca->nr_rdma_attrs) {
1680 	case 0:
1681 		break;
1682 	case 1:
1683 		if (xdr_stream_decode_u32(argp->xdr, &ca->rdma_attrs) < 0)
1684 			return nfserr_bad_xdr;
1685 		break;
1686 	default:
1687 		return nfserr_bad_xdr;
1688 	}
1689 
1690 	return nfs_ok;
1691 }
1692 
1693 static __be32
1694 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1695 			    union nfsd4_op_u *u)
1696 {
1697 	struct nfsd4_create_session *sess = &u->create_session;
1698 	__be32 status;
1699 
1700 	memset(sess, 0, sizeof(*sess));
1701 	status = nfsd4_decode_clientid4(argp, &sess->clientid);
1702 	if (status)
1703 		return status;
1704 	if (xdr_stream_decode_u32(argp->xdr, &sess->seqid) < 0)
1705 		return nfserr_bad_xdr;
1706 	if (xdr_stream_decode_u32(argp->xdr, &sess->flags) < 0)
1707 		return nfserr_bad_xdr;
1708 	status = nfsd4_decode_channel_attrs4(argp, &sess->fore_channel);
1709 	if (status)
1710 		return status;
1711 	status = nfsd4_decode_channel_attrs4(argp, &sess->back_channel);
1712 	if (status)
1713 		return status;
1714 	if (xdr_stream_decode_u32(argp->xdr, &sess->callback_prog) < 0)
1715 		return nfserr_bad_xdr;
1716 	return nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1717 }
1718 
1719 static __be32
1720 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1721 			     union nfsd4_op_u *u)
1722 {
1723 	struct nfsd4_destroy_session *destroy_session = &u->destroy_session;
1724 	return nfsd4_decode_sessionid4(argp, &destroy_session->sessionid);
1725 }
1726 
1727 static __be32
1728 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1729 			  union nfsd4_op_u *u)
1730 {
1731 	struct nfsd4_free_stateid *free_stateid = &u->free_stateid;
1732 	return nfsd4_decode_stateid4(argp, &free_stateid->fr_stateid);
1733 }
1734 
1735 #ifdef CONFIG_NFSD_PNFS
1736 static __be32
1737 nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp,
1738 		union nfsd4_op_u *u)
1739 {
1740 	struct nfsd4_getdeviceinfo *gdev = &u->getdeviceinfo;
1741 	__be32 status;
1742 
1743 	memset(gdev, 0, sizeof(*gdev));
1744 	status = nfsd4_decode_deviceid4(argp, &gdev->gd_devid);
1745 	if (status)
1746 		return status;
1747 	if (xdr_stream_decode_u32(argp->xdr, &gdev->gd_layout_type) < 0)
1748 		return nfserr_bad_xdr;
1749 	if (xdr_stream_decode_u32(argp->xdr, &gdev->gd_maxcount) < 0)
1750 		return nfserr_bad_xdr;
1751 	if (xdr_stream_decode_uint32_array(argp->xdr,
1752 					   &gdev->gd_notify_types, 1) < 0)
1753 		return nfserr_bad_xdr;
1754 
1755 	return nfs_ok;
1756 }
1757 
1758 static __be32
1759 nfsd4_decode_layoutcommit(struct nfsd4_compoundargs *argp,
1760 			  union nfsd4_op_u *u)
1761 {
1762 	struct nfsd4_layoutcommit *lcp = &u->layoutcommit;
1763 	__be32 *p, status;
1764 
1765 	memset(lcp, 0, sizeof(*lcp));
1766 	if (xdr_stream_decode_u64(argp->xdr, &lcp->lc_seg.offset) < 0)
1767 		return nfserr_bad_xdr;
1768 	if (xdr_stream_decode_u64(argp->xdr, &lcp->lc_seg.length) < 0)
1769 		return nfserr_bad_xdr;
1770 	if (xdr_stream_decode_bool(argp->xdr, &lcp->lc_reclaim) < 0)
1771 		return nfserr_bad_xdr;
1772 	status = nfsd4_decode_stateid4(argp, &lcp->lc_sid);
1773 	if (status)
1774 		return status;
1775 	if (xdr_stream_decode_u32(argp->xdr, &lcp->lc_newoffset) < 0)
1776 		return nfserr_bad_xdr;
1777 	if (lcp->lc_newoffset) {
1778 		if (xdr_stream_decode_u64(argp->xdr, &lcp->lc_last_wr) < 0)
1779 			return nfserr_bad_xdr;
1780 	} else
1781 		lcp->lc_last_wr = 0;
1782 	p = xdr_inline_decode(argp->xdr, XDR_UNIT);
1783 	if (!p)
1784 		return nfserr_bad_xdr;
1785 	if (xdr_item_is_present(p)) {
1786 		status = nfsd4_decode_nfstime4(argp, &lcp->lc_mtime);
1787 		if (status)
1788 			return status;
1789 	} else {
1790 		lcp->lc_mtime.tv_nsec = UTIME_NOW;
1791 	}
1792 	return nfsd4_decode_layoutupdate4(argp, lcp);
1793 }
1794 
1795 static __be32
1796 nfsd4_decode_layoutget(struct nfsd4_compoundargs *argp,
1797 		union nfsd4_op_u *u)
1798 {
1799 	struct nfsd4_layoutget *lgp = &u->layoutget;
1800 	__be32 status;
1801 
1802 	memset(lgp, 0, sizeof(*lgp));
1803 	if (xdr_stream_decode_u32(argp->xdr, &lgp->lg_signal) < 0)
1804 		return nfserr_bad_xdr;
1805 	if (xdr_stream_decode_u32(argp->xdr, &lgp->lg_layout_type) < 0)
1806 		return nfserr_bad_xdr;
1807 	if (xdr_stream_decode_u32(argp->xdr, &lgp->lg_seg.iomode) < 0)
1808 		return nfserr_bad_xdr;
1809 	if (xdr_stream_decode_u64(argp->xdr, &lgp->lg_seg.offset) < 0)
1810 		return nfserr_bad_xdr;
1811 	if (xdr_stream_decode_u64(argp->xdr, &lgp->lg_seg.length) < 0)
1812 		return nfserr_bad_xdr;
1813 	if (xdr_stream_decode_u64(argp->xdr, &lgp->lg_minlength) < 0)
1814 		return nfserr_bad_xdr;
1815 	status = nfsd4_decode_stateid4(argp, &lgp->lg_sid);
1816 	if (status)
1817 		return status;
1818 	if (xdr_stream_decode_u32(argp->xdr, &lgp->lg_maxcount) < 0)
1819 		return nfserr_bad_xdr;
1820 
1821 	return nfs_ok;
1822 }
1823 
1824 static __be32
1825 nfsd4_decode_layoutreturn(struct nfsd4_compoundargs *argp,
1826 		union nfsd4_op_u *u)
1827 {
1828 	struct nfsd4_layoutreturn *lrp = &u->layoutreturn;
1829 	memset(lrp, 0, sizeof(*lrp));
1830 	if (xdr_stream_decode_bool(argp->xdr, &lrp->lr_reclaim) < 0)
1831 		return nfserr_bad_xdr;
1832 	if (xdr_stream_decode_u32(argp->xdr, &lrp->lr_layout_type) < 0)
1833 		return nfserr_bad_xdr;
1834 	if (xdr_stream_decode_u32(argp->xdr, &lrp->lr_seg.iomode) < 0)
1835 		return nfserr_bad_xdr;
1836 	return nfsd4_decode_layoutreturn4(argp, lrp);
1837 }
1838 #endif /* CONFIG_NFSD_PNFS */
1839 
1840 static __be32 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1841 					   union nfsd4_op_u *u)
1842 {
1843 	struct nfsd4_secinfo_no_name *sin = &u->secinfo_no_name;
1844 	if (xdr_stream_decode_u32(argp->xdr, &sin->sin_style) < 0)
1845 		return nfserr_bad_xdr;
1846 
1847 	sin->sin_exp = NULL;
1848 	return nfs_ok;
1849 }
1850 
1851 static __be32
1852 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1853 		      union nfsd4_op_u *u)
1854 {
1855 	struct nfsd4_sequence *seq = &u->sequence;
1856 	__be32 *p, status;
1857 
1858 	status = nfsd4_decode_sessionid4(argp, &seq->sessionid);
1859 	if (status)
1860 		return status;
1861 	p = xdr_inline_decode(argp->xdr, XDR_UNIT * 4);
1862 	if (!p)
1863 		return nfserr_bad_xdr;
1864 	seq->seqid = be32_to_cpup(p++);
1865 	seq->slotid = be32_to_cpup(p++);
1866 	seq->maxslots = be32_to_cpup(p++);
1867 	seq->cachethis = be32_to_cpup(p);
1868 
1869 	seq->status_flags = 0;
1870 	return nfs_ok;
1871 }
1872 
1873 static __be32
1874 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp,
1875 			  union nfsd4_op_u *u)
1876 {
1877 	struct nfsd4_test_stateid *test_stateid = &u->test_stateid;
1878 	struct nfsd4_test_stateid_id *stateid;
1879 	__be32 status;
1880 	u32 i;
1881 
1882 	memset(test_stateid, 0, sizeof(*test_stateid));
1883 	if (xdr_stream_decode_u32(argp->xdr, &test_stateid->ts_num_ids) < 0)
1884 		return nfserr_bad_xdr;
1885 
1886 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1887 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1888 		stateid = svcxdr_tmpalloc(argp, sizeof(*stateid));
1889 		if (!stateid)
1890 			return nfserr_jukebox;
1891 		INIT_LIST_HEAD(&stateid->ts_id_list);
1892 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1893 		status = nfsd4_decode_stateid4(argp, &stateid->ts_id_stateid);
1894 		if (status)
1895 			return status;
1896 	}
1897 
1898 	return nfs_ok;
1899 }
1900 
1901 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp,
1902 					    union nfsd4_op_u *u)
1903 {
1904 	struct nfsd4_destroy_clientid *dc = &u->destroy_clientid;
1905 	return nfsd4_decode_clientid4(argp, &dc->clientid);
1906 }
1907 
1908 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp,
1909 					    union nfsd4_op_u *u)
1910 {
1911 	struct nfsd4_reclaim_complete *rc = &u->reclaim_complete;
1912 	if (xdr_stream_decode_bool(argp->xdr, &rc->rca_one_fs) < 0)
1913 		return nfserr_bad_xdr;
1914 	return nfs_ok;
1915 }
1916 
1917 static __be32
1918 nfsd4_decode_fallocate(struct nfsd4_compoundargs *argp,
1919 		       union nfsd4_op_u *u)
1920 {
1921 	struct nfsd4_fallocate *fallocate = &u->allocate;
1922 	__be32 status;
1923 
1924 	status = nfsd4_decode_stateid4(argp, &fallocate->falloc_stateid);
1925 	if (status)
1926 		return status;
1927 	if (xdr_stream_decode_u64(argp->xdr, &fallocate->falloc_offset) < 0)
1928 		return nfserr_bad_xdr;
1929 	if (xdr_stream_decode_u64(argp->xdr, &fallocate->falloc_length) < 0)
1930 		return nfserr_bad_xdr;
1931 
1932 	return nfs_ok;
1933 }
1934 
1935 static __be32 nfsd4_decode_nl4_server(struct nfsd4_compoundargs *argp,
1936 				      struct nl4_server *ns)
1937 {
1938 	struct nfs42_netaddr *naddr;
1939 	__be32 *p;
1940 
1941 	if (xdr_stream_decode_u32(argp->xdr, &ns->nl4_type) < 0)
1942 		return nfserr_bad_xdr;
1943 
1944 	/* currently support for 1 inter-server source server */
1945 	switch (ns->nl4_type) {
1946 	case NL4_NETADDR:
1947 		naddr = &ns->u.nl4_addr;
1948 
1949 		if (xdr_stream_decode_u32(argp->xdr, &naddr->netid_len) < 0)
1950 			return nfserr_bad_xdr;
1951 		if (naddr->netid_len > RPCBIND_MAXNETIDLEN)
1952 			return nfserr_bad_xdr;
1953 
1954 		p = xdr_inline_decode(argp->xdr, naddr->netid_len);
1955 		if (!p)
1956 			return nfserr_bad_xdr;
1957 		memcpy(naddr->netid, p, naddr->netid_len);
1958 
1959 		if (xdr_stream_decode_u32(argp->xdr, &naddr->addr_len) < 0)
1960 			return nfserr_bad_xdr;
1961 		if (naddr->addr_len > RPCBIND_MAXUADDRLEN)
1962 			return nfserr_bad_xdr;
1963 
1964 		p = xdr_inline_decode(argp->xdr, naddr->addr_len);
1965 		if (!p)
1966 			return nfserr_bad_xdr;
1967 		memcpy(naddr->addr, p, naddr->addr_len);
1968 		break;
1969 	default:
1970 		return nfserr_bad_xdr;
1971 	}
1972 
1973 	return nfs_ok;
1974 }
1975 
1976 static __be32
1977 nfsd4_decode_copy(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
1978 {
1979 	struct nfsd4_copy *copy = &u->copy;
1980 	u32 consecutive, i, count, sync;
1981 	struct nl4_server *ns_dummy;
1982 	__be32 status;
1983 
1984 	memset(copy, 0, sizeof(*copy));
1985 	status = nfsd4_decode_stateid4(argp, &copy->cp_src_stateid);
1986 	if (status)
1987 		return status;
1988 	status = nfsd4_decode_stateid4(argp, &copy->cp_dst_stateid);
1989 	if (status)
1990 		return status;
1991 	if (xdr_stream_decode_u64(argp->xdr, &copy->cp_src_pos) < 0)
1992 		return nfserr_bad_xdr;
1993 	if (xdr_stream_decode_u64(argp->xdr, &copy->cp_dst_pos) < 0)
1994 		return nfserr_bad_xdr;
1995 	if (xdr_stream_decode_u64(argp->xdr, &copy->cp_count) < 0)
1996 		return nfserr_bad_xdr;
1997 	/* ca_consecutive: we always do consecutive copies */
1998 	if (xdr_stream_decode_u32(argp->xdr, &consecutive) < 0)
1999 		return nfserr_bad_xdr;
2000 	if (xdr_stream_decode_bool(argp->xdr, &sync) < 0)
2001 		return nfserr_bad_xdr;
2002 	nfsd4_copy_set_sync(copy, sync);
2003 
2004 	if (xdr_stream_decode_u32(argp->xdr, &count) < 0)
2005 		return nfserr_bad_xdr;
2006 	copy->cp_src = svcxdr_tmpalloc(argp, sizeof(*copy->cp_src));
2007 	if (copy->cp_src == NULL)
2008 		return nfserr_jukebox;
2009 	if (count == 0) { /* intra-server copy */
2010 		__set_bit(NFSD4_COPY_F_INTRA, &copy->cp_flags);
2011 		return nfs_ok;
2012 	}
2013 
2014 	/* decode all the supplied server addresses but use only the first */
2015 	status = nfsd4_decode_nl4_server(argp, copy->cp_src);
2016 	if (status)
2017 		return status;
2018 
2019 	ns_dummy = kmalloc(sizeof(struct nl4_server), GFP_KERNEL);
2020 	if (ns_dummy == NULL)
2021 		return nfserr_jukebox;
2022 	for (i = 0; i < count - 1; i++) {
2023 		status = nfsd4_decode_nl4_server(argp, ns_dummy);
2024 		if (status) {
2025 			kfree(ns_dummy);
2026 			return status;
2027 		}
2028 	}
2029 	kfree(ns_dummy);
2030 
2031 	return nfs_ok;
2032 }
2033 
2034 static __be32
2035 nfsd4_decode_copy_notify(struct nfsd4_compoundargs *argp,
2036 			 union nfsd4_op_u *u)
2037 {
2038 	struct nfsd4_copy_notify *cn = &u->copy_notify;
2039 	__be32 status;
2040 
2041 	memset(cn, 0, sizeof(*cn));
2042 	cn->cpn_src = svcxdr_tmpalloc(argp, sizeof(*cn->cpn_src));
2043 	if (cn->cpn_src == NULL)
2044 		return nfserr_jukebox;
2045 	cn->cpn_dst = svcxdr_tmpalloc(argp, sizeof(*cn->cpn_dst));
2046 	if (cn->cpn_dst == NULL)
2047 		return nfserr_jukebox;
2048 
2049 	status = nfsd4_decode_stateid4(argp, &cn->cpn_src_stateid);
2050 	if (status)
2051 		return status;
2052 	return nfsd4_decode_nl4_server(argp, cn->cpn_dst);
2053 }
2054 
2055 static __be32
2056 nfsd4_decode_offload_status(struct nfsd4_compoundargs *argp,
2057 			    union nfsd4_op_u *u)
2058 {
2059 	struct nfsd4_offload_status *os = &u->offload_status;
2060 	os->count = 0;
2061 	os->status = 0;
2062 	return nfsd4_decode_stateid4(argp, &os->stateid);
2063 }
2064 
2065 static __be32
2066 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
2067 {
2068 	struct nfsd4_seek *seek = &u->seek;
2069 	__be32 status;
2070 
2071 	status = nfsd4_decode_stateid4(argp, &seek->seek_stateid);
2072 	if (status)
2073 		return status;
2074 	if (xdr_stream_decode_u64(argp->xdr, &seek->seek_offset) < 0)
2075 		return nfserr_bad_xdr;
2076 	if (xdr_stream_decode_u32(argp->xdr, &seek->seek_whence) < 0)
2077 		return nfserr_bad_xdr;
2078 
2079 	seek->seek_eof = 0;
2080 	seek->seek_pos = 0;
2081 	return nfs_ok;
2082 }
2083 
2084 static __be32
2085 nfsd4_decode_clone(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u)
2086 {
2087 	struct nfsd4_clone *clone = &u->clone;
2088 	__be32 status;
2089 
2090 	status = nfsd4_decode_stateid4(argp, &clone->cl_src_stateid);
2091 	if (status)
2092 		return status;
2093 	status = nfsd4_decode_stateid4(argp, &clone->cl_dst_stateid);
2094 	if (status)
2095 		return status;
2096 	if (xdr_stream_decode_u64(argp->xdr, &clone->cl_src_pos) < 0)
2097 		return nfserr_bad_xdr;
2098 	if (xdr_stream_decode_u64(argp->xdr, &clone->cl_dst_pos) < 0)
2099 		return nfserr_bad_xdr;
2100 	if (xdr_stream_decode_u64(argp->xdr, &clone->cl_count) < 0)
2101 		return nfserr_bad_xdr;
2102 
2103 	return nfs_ok;
2104 }
2105 
2106 /*
2107  * XDR data that is more than PAGE_SIZE in size is normally part of a
2108  * read or write. However, the size of extended attributes is limited
2109  * by the maximum request size, and then further limited by the underlying
2110  * filesystem limits. This can exceed PAGE_SIZE (currently, XATTR_SIZE_MAX
2111  * is 64k). Since there is no kvec- or page-based interface to xattrs,
2112  * and we're not dealing with contiguous pages, we need to do some copying.
2113  */
2114 
2115 /*
2116  * Decode data into buffer.
2117  */
2118 static __be32
2119 nfsd4_vbuf_from_vector(struct nfsd4_compoundargs *argp, struct xdr_buf *xdr,
2120 		       char **bufp, u32 buflen)
2121 {
2122 	struct page **pages = xdr->pages;
2123 	struct kvec *head = xdr->head;
2124 	char *tmp, *dp;
2125 	u32 len;
2126 
2127 	if (buflen <= head->iov_len) {
2128 		/*
2129 		 * We're in luck, the head has enough space. Just return
2130 		 * the head, no need for copying.
2131 		 */
2132 		*bufp = head->iov_base;
2133 		return 0;
2134 	}
2135 
2136 	tmp = svcxdr_tmpalloc(argp, buflen);
2137 	if (tmp == NULL)
2138 		return nfserr_jukebox;
2139 
2140 	dp = tmp;
2141 	memcpy(dp, head->iov_base, head->iov_len);
2142 	buflen -= head->iov_len;
2143 	dp += head->iov_len;
2144 
2145 	while (buflen > 0) {
2146 		len = min_t(u32, buflen, PAGE_SIZE);
2147 		memcpy(dp, page_address(*pages), len);
2148 
2149 		buflen -= len;
2150 		dp += len;
2151 		pages++;
2152 	}
2153 
2154 	*bufp = tmp;
2155 	return 0;
2156 }
2157 
2158 /*
2159  * Get a user extended attribute name from the XDR buffer.
2160  * It will not have the "user." prefix, so prepend it.
2161  * Lastly, check for nul characters in the name.
2162  */
2163 static __be32
2164 nfsd4_decode_xattr_name(struct nfsd4_compoundargs *argp, char **namep)
2165 {
2166 	char *name, *sp, *dp;
2167 	u32 namelen, cnt;
2168 	__be32 *p;
2169 
2170 	if (xdr_stream_decode_u32(argp->xdr, &namelen) < 0)
2171 		return nfserr_bad_xdr;
2172 	if (namelen > (XATTR_NAME_MAX - XATTR_USER_PREFIX_LEN))
2173 		return nfserr_nametoolong;
2174 	if (namelen == 0)
2175 		return nfserr_bad_xdr;
2176 	p = xdr_inline_decode(argp->xdr, namelen);
2177 	if (!p)
2178 		return nfserr_bad_xdr;
2179 	name = svcxdr_tmpalloc(argp, namelen + XATTR_USER_PREFIX_LEN + 1);
2180 	if (!name)
2181 		return nfserr_jukebox;
2182 	memcpy(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
2183 
2184 	/*
2185 	 * Copy the extended attribute name over while checking for 0
2186 	 * characters.
2187 	 */
2188 	sp = (char *)p;
2189 	dp = name + XATTR_USER_PREFIX_LEN;
2190 	cnt = namelen;
2191 
2192 	while (cnt-- > 0) {
2193 		if (*sp == '\0')
2194 			return nfserr_bad_xdr;
2195 		*dp++ = *sp++;
2196 	}
2197 	*dp = '\0';
2198 
2199 	*namep = name;
2200 
2201 	return nfs_ok;
2202 }
2203 
2204 /*
2205  * A GETXATTR op request comes without a length specifier. We just set the
2206  * maximum length for the reply based on XATTR_SIZE_MAX and the maximum
2207  * channel reply size. nfsd_getxattr will probe the length of the xattr,
2208  * check it against getxa_len, and allocate + return the value.
2209  */
2210 static __be32
2211 nfsd4_decode_getxattr(struct nfsd4_compoundargs *argp,
2212 		      union nfsd4_op_u *u)
2213 {
2214 	struct nfsd4_getxattr *getxattr = &u->getxattr;
2215 	__be32 status;
2216 	u32 maxcount;
2217 
2218 	memset(getxattr, 0, sizeof(*getxattr));
2219 	status = nfsd4_decode_xattr_name(argp, &getxattr->getxa_name);
2220 	if (status)
2221 		return status;
2222 
2223 	maxcount = svc_max_payload(argp->rqstp);
2224 	maxcount = min_t(u32, XATTR_SIZE_MAX, maxcount);
2225 
2226 	getxattr->getxa_len = maxcount;
2227 	return nfs_ok;
2228 }
2229 
2230 static __be32
2231 nfsd4_decode_setxattr(struct nfsd4_compoundargs *argp,
2232 		      union nfsd4_op_u *u)
2233 {
2234 	struct nfsd4_setxattr *setxattr = &u->setxattr;
2235 	u32 flags, maxcount, size;
2236 	__be32 status;
2237 
2238 	memset(setxattr, 0, sizeof(*setxattr));
2239 
2240 	if (xdr_stream_decode_u32(argp->xdr, &flags) < 0)
2241 		return nfserr_bad_xdr;
2242 
2243 	if (flags > SETXATTR4_REPLACE)
2244 		return nfserr_inval;
2245 	setxattr->setxa_flags = flags;
2246 
2247 	status = nfsd4_decode_xattr_name(argp, &setxattr->setxa_name);
2248 	if (status)
2249 		return status;
2250 
2251 	maxcount = svc_max_payload(argp->rqstp);
2252 	maxcount = min_t(u32, XATTR_SIZE_MAX, maxcount);
2253 
2254 	if (xdr_stream_decode_u32(argp->xdr, &size) < 0)
2255 		return nfserr_bad_xdr;
2256 	if (size > maxcount)
2257 		return nfserr_xattr2big;
2258 
2259 	setxattr->setxa_len = size;
2260 	if (size > 0) {
2261 		struct xdr_buf payload;
2262 
2263 		if (!xdr_stream_subsegment(argp->xdr, &payload, size))
2264 			return nfserr_bad_xdr;
2265 		status = nfsd4_vbuf_from_vector(argp, &payload,
2266 						&setxattr->setxa_buf, size);
2267 	}
2268 
2269 	return nfs_ok;
2270 }
2271 
2272 static __be32
2273 nfsd4_decode_listxattrs(struct nfsd4_compoundargs *argp,
2274 			union nfsd4_op_u *u)
2275 {
2276 	struct nfsd4_listxattrs *listxattrs = &u->listxattrs;
2277 	u32 maxcount;
2278 
2279 	memset(listxattrs, 0, sizeof(*listxattrs));
2280 
2281 	if (xdr_stream_decode_u64(argp->xdr, &listxattrs->lsxa_cookie) < 0)
2282 		return nfserr_bad_xdr;
2283 
2284 	/*
2285 	 * If the cookie  is too large to have even one user.x attribute
2286 	 * plus trailing '\0' left in a maximum size buffer, it's invalid.
2287 	 */
2288 	if (listxattrs->lsxa_cookie >=
2289 	    (XATTR_LIST_MAX / (XATTR_USER_PREFIX_LEN + 2)))
2290 		return nfserr_badcookie;
2291 
2292 	if (xdr_stream_decode_u32(argp->xdr, &maxcount) < 0)
2293 		return nfserr_bad_xdr;
2294 	if (maxcount < 8)
2295 		/* Always need at least 2 words (length and one character) */
2296 		return nfserr_inval;
2297 
2298 	maxcount = min(maxcount, svc_max_payload(argp->rqstp));
2299 	listxattrs->lsxa_maxcount = maxcount;
2300 
2301 	return nfs_ok;
2302 }
2303 
2304 static __be32
2305 nfsd4_decode_removexattr(struct nfsd4_compoundargs *argp,
2306 			 union nfsd4_op_u *u)
2307 {
2308 	struct nfsd4_removexattr *removexattr = &u->removexattr;
2309 	memset(removexattr, 0, sizeof(*removexattr));
2310 	return nfsd4_decode_xattr_name(argp, &removexattr->rmxa_name);
2311 }
2312 
2313 static __be32
2314 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, union nfsd4_op_u *p)
2315 {
2316 	return nfs_ok;
2317 }
2318 
2319 static __be32
2320 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, union nfsd4_op_u *p)
2321 {
2322 	return nfserr_notsupp;
2323 }
2324 
2325 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, union nfsd4_op_u *u);
2326 
2327 static const nfsd4_dec nfsd4_dec_ops[] = {
2328 	[OP_ACCESS]		= nfsd4_decode_access,
2329 	[OP_CLOSE]		= nfsd4_decode_close,
2330 	[OP_COMMIT]		= nfsd4_decode_commit,
2331 	[OP_CREATE]		= nfsd4_decode_create,
2332 	[OP_DELEGPURGE]		= nfsd4_decode_notsupp,
2333 	[OP_DELEGRETURN]	= nfsd4_decode_delegreturn,
2334 	[OP_GETATTR]		= nfsd4_decode_getattr,
2335 	[OP_GETFH]		= nfsd4_decode_noop,
2336 	[OP_LINK]		= nfsd4_decode_link,
2337 	[OP_LOCK]		= nfsd4_decode_lock,
2338 	[OP_LOCKT]		= nfsd4_decode_lockt,
2339 	[OP_LOCKU]		= nfsd4_decode_locku,
2340 	[OP_LOOKUP]		= nfsd4_decode_lookup,
2341 	[OP_LOOKUPP]		= nfsd4_decode_noop,
2342 	[OP_NVERIFY]		= nfsd4_decode_verify,
2343 	[OP_OPEN]		= nfsd4_decode_open,
2344 	[OP_OPENATTR]		= nfsd4_decode_notsupp,
2345 	[OP_OPEN_CONFIRM]	= nfsd4_decode_open_confirm,
2346 	[OP_OPEN_DOWNGRADE]	= nfsd4_decode_open_downgrade,
2347 	[OP_PUTFH]		= nfsd4_decode_putfh,
2348 	[OP_PUTPUBFH]		= nfsd4_decode_putpubfh,
2349 	[OP_PUTROOTFH]		= nfsd4_decode_noop,
2350 	[OP_READ]		= nfsd4_decode_read,
2351 	[OP_READDIR]		= nfsd4_decode_readdir,
2352 	[OP_READLINK]		= nfsd4_decode_noop,
2353 	[OP_REMOVE]		= nfsd4_decode_remove,
2354 	[OP_RENAME]		= nfsd4_decode_rename,
2355 	[OP_RENEW]		= nfsd4_decode_renew,
2356 	[OP_RESTOREFH]		= nfsd4_decode_noop,
2357 	[OP_SAVEFH]		= nfsd4_decode_noop,
2358 	[OP_SECINFO]		= nfsd4_decode_secinfo,
2359 	[OP_SETATTR]		= nfsd4_decode_setattr,
2360 	[OP_SETCLIENTID]	= nfsd4_decode_setclientid,
2361 	[OP_SETCLIENTID_CONFIRM] = nfsd4_decode_setclientid_confirm,
2362 	[OP_VERIFY]		= nfsd4_decode_verify,
2363 	[OP_WRITE]		= nfsd4_decode_write,
2364 	[OP_RELEASE_LOCKOWNER]	= nfsd4_decode_release_lockowner,
2365 
2366 	/* new operations for NFSv4.1 */
2367 	[OP_BACKCHANNEL_CTL]	= nfsd4_decode_backchannel_ctl,
2368 	[OP_BIND_CONN_TO_SESSION] = nfsd4_decode_bind_conn_to_session,
2369 	[OP_EXCHANGE_ID]	= nfsd4_decode_exchange_id,
2370 	[OP_CREATE_SESSION]	= nfsd4_decode_create_session,
2371 	[OP_DESTROY_SESSION]	= nfsd4_decode_destroy_session,
2372 	[OP_FREE_STATEID]	= nfsd4_decode_free_stateid,
2373 	[OP_GET_DIR_DELEGATION]	= nfsd4_decode_notsupp,
2374 #ifdef CONFIG_NFSD_PNFS
2375 	[OP_GETDEVICEINFO]	= nfsd4_decode_getdeviceinfo,
2376 	[OP_GETDEVICELIST]	= nfsd4_decode_notsupp,
2377 	[OP_LAYOUTCOMMIT]	= nfsd4_decode_layoutcommit,
2378 	[OP_LAYOUTGET]		= nfsd4_decode_layoutget,
2379 	[OP_LAYOUTRETURN]	= nfsd4_decode_layoutreturn,
2380 #else
2381 	[OP_GETDEVICEINFO]	= nfsd4_decode_notsupp,
2382 	[OP_GETDEVICELIST]	= nfsd4_decode_notsupp,
2383 	[OP_LAYOUTCOMMIT]	= nfsd4_decode_notsupp,
2384 	[OP_LAYOUTGET]		= nfsd4_decode_notsupp,
2385 	[OP_LAYOUTRETURN]	= nfsd4_decode_notsupp,
2386 #endif
2387 	[OP_SECINFO_NO_NAME]	= nfsd4_decode_secinfo_no_name,
2388 	[OP_SEQUENCE]		= nfsd4_decode_sequence,
2389 	[OP_SET_SSV]		= nfsd4_decode_notsupp,
2390 	[OP_TEST_STATEID]	= nfsd4_decode_test_stateid,
2391 	[OP_WANT_DELEGATION]	= nfsd4_decode_notsupp,
2392 	[OP_DESTROY_CLIENTID]	= nfsd4_decode_destroy_clientid,
2393 	[OP_RECLAIM_COMPLETE]	= nfsd4_decode_reclaim_complete,
2394 
2395 	/* new operations for NFSv4.2 */
2396 	[OP_ALLOCATE]		= nfsd4_decode_fallocate,
2397 	[OP_COPY]		= nfsd4_decode_copy,
2398 	[OP_COPY_NOTIFY]	= nfsd4_decode_copy_notify,
2399 	[OP_DEALLOCATE]		= nfsd4_decode_fallocate,
2400 	[OP_IO_ADVISE]		= nfsd4_decode_notsupp,
2401 	[OP_LAYOUTERROR]	= nfsd4_decode_notsupp,
2402 	[OP_LAYOUTSTATS]	= nfsd4_decode_notsupp,
2403 	[OP_OFFLOAD_CANCEL]	= nfsd4_decode_offload_status,
2404 	[OP_OFFLOAD_STATUS]	= nfsd4_decode_offload_status,
2405 	[OP_READ_PLUS]		= nfsd4_decode_read,
2406 	[OP_SEEK]		= nfsd4_decode_seek,
2407 	[OP_WRITE_SAME]		= nfsd4_decode_notsupp,
2408 	[OP_CLONE]		= nfsd4_decode_clone,
2409 	/* RFC 8276 extended atributes operations */
2410 	[OP_GETXATTR]		= nfsd4_decode_getxattr,
2411 	[OP_SETXATTR]		= nfsd4_decode_setxattr,
2412 	[OP_LISTXATTRS]		= nfsd4_decode_listxattrs,
2413 	[OP_REMOVEXATTR]	= nfsd4_decode_removexattr,
2414 };
2415 
2416 static inline bool
2417 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
2418 {
2419 	if (op->opnum < FIRST_NFS4_OP)
2420 		return false;
2421 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
2422 		return false;
2423 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
2424 		return false;
2425 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
2426 		return false;
2427 	return true;
2428 }
2429 
2430 static bool
2431 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
2432 {
2433 	struct nfsd4_op *op;
2434 	bool cachethis = false;
2435 	int auth_slack= argp->rqstp->rq_auth_slack;
2436 	int max_reply = auth_slack + 8; /* opcnt, status */
2437 	int readcount = 0;
2438 	int readbytes = 0;
2439 	__be32 *p;
2440 	int i;
2441 
2442 	if (xdr_stream_decode_u32(argp->xdr, &argp->taglen) < 0)
2443 		return false;
2444 	max_reply += XDR_UNIT;
2445 	argp->tag = NULL;
2446 	if (unlikely(argp->taglen)) {
2447 		if (argp->taglen > NFSD4_MAX_TAGLEN)
2448 			return false;
2449 		p = xdr_inline_decode(argp->xdr, argp->taglen);
2450 		if (!p)
2451 			return false;
2452 		argp->tag = svcxdr_savemem(argp, p, argp->taglen);
2453 		if (!argp->tag)
2454 			return false;
2455 		max_reply += xdr_align_size(argp->taglen);
2456 	}
2457 
2458 	if (xdr_stream_decode_u32(argp->xdr, &argp->minorversion) < 0)
2459 		return false;
2460 	if (xdr_stream_decode_u32(argp->xdr, &argp->client_opcnt) < 0)
2461 		return false;
2462 	argp->opcnt = min_t(u32, argp->client_opcnt,
2463 			    NFSD_MAX_OPS_PER_COMPOUND);
2464 
2465 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
2466 		argp->ops = vcalloc(argp->opcnt, sizeof(*argp->ops));
2467 		if (!argp->ops) {
2468 			argp->ops = argp->iops;
2469 			return false;
2470 		}
2471 	}
2472 
2473 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
2474 		argp->opcnt = 0;
2475 
2476 	for (i = 0; i < argp->opcnt; i++) {
2477 		op = &argp->ops[i];
2478 		op->replay = NULL;
2479 		op->opdesc = NULL;
2480 
2481 		if (xdr_stream_decode_u32(argp->xdr, &op->opnum) < 0)
2482 			return false;
2483 		if (nfsd4_opnum_in_range(argp, op)) {
2484 			op->opdesc = OPDESC(op);
2485 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
2486 			if (op->status != nfs_ok)
2487 				trace_nfsd_compound_decode_err(argp->rqstp,
2488 							       argp->opcnt, i,
2489 							       op->opnum,
2490 							       op->status);
2491 		} else {
2492 			op->opnum = OP_ILLEGAL;
2493 			op->status = nfserr_op_illegal;
2494 		}
2495 
2496 		/*
2497 		 * We'll try to cache the result in the DRC if any one
2498 		 * op in the compound wants to be cached:
2499 		 */
2500 		cachethis |= nfsd4_cache_this_op(op);
2501 
2502 		if (op->opnum == OP_READ || op->opnum == OP_READ_PLUS) {
2503 			readcount++;
2504 			readbytes += nfsd4_max_reply(argp->rqstp, op);
2505 		} else
2506 			max_reply += nfsd4_max_reply(argp->rqstp, op);
2507 		/*
2508 		 * OP_LOCK and OP_LOCKT may return a conflicting lock.
2509 		 * (Special case because it will just skip encoding this
2510 		 * if it runs out of xdr buffer space, and it is the only
2511 		 * operation that behaves this way.)
2512 		 */
2513 		if (op->opnum == OP_LOCK || op->opnum == OP_LOCKT)
2514 			max_reply += NFS4_OPAQUE_LIMIT;
2515 
2516 		if (op->status) {
2517 			argp->opcnt = i+1;
2518 			break;
2519 		}
2520 	}
2521 	/* Sessions make the DRC unnecessary: */
2522 	if (argp->minorversion)
2523 		cachethis = false;
2524 	svc_reserve(argp->rqstp, max_reply + readbytes);
2525 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
2526 
2527 	argp->splice_ok = nfsd_read_splice_ok(argp->rqstp);
2528 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
2529 		argp->splice_ok = false;
2530 
2531 	return true;
2532 }
2533 
2534 static __be32 nfsd4_encode_nfs_fh4(struct xdr_stream *xdr,
2535 				   struct knfsd_fh *fh_handle)
2536 {
2537 	return nfsd4_encode_opaque(xdr, fh_handle->fh_raw, fh_handle->fh_size);
2538 }
2539 
2540 /* This is a frequently-encoded type; open-coded for speed */
2541 static __be32 nfsd4_encode_nfstime4(struct xdr_stream *xdr,
2542 				    const struct timespec64 *tv)
2543 {
2544 	__be32 *p;
2545 
2546 	p = xdr_reserve_space(xdr, XDR_UNIT * 3);
2547 	if (!p)
2548 		return nfserr_resource;
2549 	p = xdr_encode_hyper(p, tv->tv_sec);
2550 	*p = cpu_to_be32(tv->tv_nsec);
2551 	return nfs_ok;
2552 }
2553 
2554 static __be32 nfsd4_encode_specdata4(struct xdr_stream *xdr,
2555 				     unsigned int major, unsigned int minor)
2556 {
2557 	__be32 status;
2558 
2559 	status = nfsd4_encode_uint32_t(xdr, major);
2560 	if (status != nfs_ok)
2561 		return status;
2562 	return nfsd4_encode_uint32_t(xdr, minor);
2563 }
2564 
2565 static __be32
2566 nfsd4_encode_change_info4(struct xdr_stream *xdr, const struct nfsd4_change_info *c)
2567 {
2568 	__be32 status;
2569 
2570 	status = nfsd4_encode_bool(xdr, c->atomic);
2571 	if (status != nfs_ok)
2572 		return status;
2573 	status = nfsd4_encode_changeid4(xdr, c->before_change);
2574 	if (status != nfs_ok)
2575 		return status;
2576 	return nfsd4_encode_changeid4(xdr, c->after_change);
2577 }
2578 
2579 static __be32 nfsd4_encode_netaddr4(struct xdr_stream *xdr,
2580 				    const struct nfs42_netaddr *addr)
2581 {
2582 	__be32 status;
2583 
2584 	/* na_r_netid */
2585 	status = nfsd4_encode_opaque(xdr, addr->netid, addr->netid_len);
2586 	if (status != nfs_ok)
2587 		return status;
2588 	/* na_r_addr */
2589 	return nfsd4_encode_opaque(xdr, addr->addr, addr->addr_len);
2590 }
2591 
2592 /* Encode as an array of strings the string given with components
2593  * separated @sep, escaped with esc_enter and esc_exit.
2594  */
2595 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
2596 					  char *components, char esc_enter,
2597 					  char esc_exit)
2598 {
2599 	__be32 *p;
2600 	__be32 pathlen;
2601 	int pathlen_offset;
2602 	int strlen, count=0;
2603 	char *str, *end, *next;
2604 
2605 	dprintk("nfsd4_encode_components(%s)\n", components);
2606 
2607 	pathlen_offset = xdr->buf->len;
2608 	p = xdr_reserve_space(xdr, 4);
2609 	if (!p)
2610 		return nfserr_resource;
2611 	p++; /* We will fill this in with @count later */
2612 
2613 	end = str = components;
2614 	while (*end) {
2615 		bool found_esc = false;
2616 
2617 		/* try to parse as esc_start, ..., esc_end, sep */
2618 		if (*str == esc_enter) {
2619 			for (; *end && (*end != esc_exit); end++)
2620 				/* find esc_exit or end of string */;
2621 			next = end + 1;
2622 			if (*end && (!*next || *next == sep)) {
2623 				str++;
2624 				found_esc = true;
2625 			}
2626 		}
2627 
2628 		if (!found_esc)
2629 			for (; *end && (*end != sep); end++)
2630 				/* find sep or end of string */;
2631 
2632 		strlen = end - str;
2633 		if (strlen) {
2634 			p = xdr_reserve_space(xdr, strlen + 4);
2635 			if (!p)
2636 				return nfserr_resource;
2637 			p = xdr_encode_opaque(p, str, strlen);
2638 			count++;
2639 		}
2640 		else
2641 			end++;
2642 		if (found_esc)
2643 			end = next;
2644 
2645 		str = end;
2646 	}
2647 	pathlen = htonl(count);
2648 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
2649 	return 0;
2650 }
2651 
2652 /* Encode as an array of strings the string given with components
2653  * separated @sep.
2654  */
2655 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
2656 				      char *components)
2657 {
2658 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
2659 }
2660 
2661 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
2662 					struct nfsd4_fs_location *location)
2663 {
2664 	__be32 status;
2665 
2666 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
2667 						'[', ']');
2668 	if (status)
2669 		return status;
2670 	status = nfsd4_encode_components(xdr, '/', location->path);
2671 	if (status)
2672 		return status;
2673 	return nfs_ok;
2674 }
2675 
2676 static __be32 nfsd4_encode_pathname4(struct xdr_stream *xdr,
2677 				     const struct path *root,
2678 				     const struct path *path)
2679 {
2680 	struct path cur = *path;
2681 	__be32 *p;
2682 	struct dentry **components = NULL;
2683 	unsigned int ncomponents = 0;
2684 	__be32 err = nfserr_jukebox;
2685 
2686 	dprintk("nfsd4_encode_components(");
2687 
2688 	path_get(&cur);
2689 	/* First walk the path up to the nfsd root, and store the
2690 	 * dentries/path components in an array.
2691 	 */
2692 	for (;;) {
2693 		if (path_equal(&cur, root))
2694 			break;
2695 		if (cur.dentry == cur.mnt->mnt_root) {
2696 			if (follow_up(&cur))
2697 				continue;
2698 			goto out_free;
2699 		}
2700 		if ((ncomponents & 15) == 0) {
2701 			struct dentry **new;
2702 			new = krealloc(components,
2703 					sizeof(*new) * (ncomponents + 16),
2704 					GFP_KERNEL);
2705 			if (!new)
2706 				goto out_free;
2707 			components = new;
2708 		}
2709 		components[ncomponents++] = cur.dentry;
2710 		cur.dentry = dget_parent(cur.dentry);
2711 	}
2712 	err = nfserr_resource;
2713 	p = xdr_reserve_space(xdr, 4);
2714 	if (!p)
2715 		goto out_free;
2716 	*p++ = cpu_to_be32(ncomponents);
2717 
2718 	while (ncomponents) {
2719 		struct dentry *dentry = components[ncomponents - 1];
2720 		unsigned int len;
2721 
2722 		spin_lock(&dentry->d_lock);
2723 		len = dentry->d_name.len;
2724 		p = xdr_reserve_space(xdr, len + 4);
2725 		if (!p) {
2726 			spin_unlock(&dentry->d_lock);
2727 			goto out_free;
2728 		}
2729 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
2730 		dprintk("/%pd", dentry);
2731 		spin_unlock(&dentry->d_lock);
2732 		dput(dentry);
2733 		ncomponents--;
2734 	}
2735 
2736 	err = 0;
2737 out_free:
2738 	dprintk(")\n");
2739 	while (ncomponents)
2740 		dput(components[--ncomponents]);
2741 	kfree(components);
2742 	path_put(&cur);
2743 	return err;
2744 }
2745 
2746 static __be32 nfsd4_encode_fs_locations4(struct xdr_stream *xdr,
2747 					 struct svc_rqst *rqstp,
2748 					 struct svc_export *exp)
2749 {
2750 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
2751 	struct svc_export *exp_ps;
2752 	unsigned int i;
2753 	__be32 status;
2754 
2755 	/* fs_root */
2756 	exp_ps = rqst_find_fsidzero_export(rqstp);
2757 	if (IS_ERR(exp_ps))
2758 		return nfserrno(PTR_ERR(exp_ps));
2759 	status = nfsd4_encode_pathname4(xdr, &exp_ps->ex_path, &exp->ex_path);
2760 	exp_put(exp_ps);
2761 	if (status != nfs_ok)
2762 		return status;
2763 
2764 	/* locations<> */
2765 	if (xdr_stream_encode_u32(xdr, fslocs->locations_count) != XDR_UNIT)
2766 		return nfserr_resource;
2767 	for (i = 0; i < fslocs->locations_count; i++) {
2768 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
2769 		if (status != nfs_ok)
2770 			return status;
2771 	}
2772 
2773 	return nfs_ok;
2774 }
2775 
2776 static __be32 nfsd4_encode_nfsace4(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2777 				   struct nfs4_ace *ace)
2778 {
2779 	__be32 status;
2780 
2781 	/* type */
2782 	status = nfsd4_encode_acetype4(xdr, ace->type);
2783 	if (status != nfs_ok)
2784 		return nfserr_resource;
2785 	/* flag */
2786 	status = nfsd4_encode_aceflag4(xdr, ace->flag);
2787 	if (status != nfs_ok)
2788 		return nfserr_resource;
2789 	/* access mask */
2790 	status = nfsd4_encode_acemask4(xdr, ace->access_mask & NFS4_ACE_MASK_ALL);
2791 	if (status != nfs_ok)
2792 		return nfserr_resource;
2793 	/* who */
2794 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
2795 		return nfs4_acl_write_who(xdr, ace->whotype);
2796 	if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
2797 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
2798 	return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
2799 }
2800 
2801 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
2802 			      FATTR4_WORD0_RDATTR_ERROR)
2803 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2804 #define WORD2_ABSENT_FS_ATTRS 0
2805 
2806 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2807 static inline __be32
2808 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2809 			    void *context, int len)
2810 {
2811 	__be32 *p;
2812 
2813 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2814 	if (!p)
2815 		return nfserr_resource;
2816 
2817 	/*
2818 	 * For now we use a 0 here to indicate the null translation; in
2819 	 * the future we may place a call to translation code here.
2820 	 */
2821 	*p++ = cpu_to_be32(0); /* lfs */
2822 	*p++ = cpu_to_be32(0); /* pi */
2823 	p = xdr_encode_opaque(p, context, len);
2824 	return 0;
2825 }
2826 #else
2827 static inline __be32
2828 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2829 			    void *context, int len)
2830 { return 0; }
2831 #endif
2832 
2833 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *bmval2, u32 *rdattr_err)
2834 {
2835 	/* As per referral draft:  */
2836 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2837 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2838 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2839 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2840 			*rdattr_err = NFSERR_MOVED;
2841 		else
2842 			return nfserr_moved;
2843 	}
2844 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2845 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2846 	*bmval2 &= WORD2_ABSENT_FS_ATTRS;
2847 	return 0;
2848 }
2849 
2850 
2851 static int nfsd4_get_mounted_on_ino(struct svc_export *exp, u64 *pino)
2852 {
2853 	struct path path = exp->ex_path;
2854 	struct kstat stat;
2855 	int err;
2856 
2857 	path_get(&path);
2858 	while (follow_up(&path)) {
2859 		if (path.dentry != path.mnt->mnt_root)
2860 			break;
2861 	}
2862 	err = vfs_getattr(&path, &stat, STATX_INO, AT_STATX_SYNC_AS_STAT);
2863 	path_put(&path);
2864 	if (!err)
2865 		*pino = stat.ino;
2866 	return err;
2867 }
2868 
2869 static __be32
2870 nfsd4_encode_bitmap4(struct xdr_stream *xdr, u32 bmval0, u32 bmval1, u32 bmval2)
2871 {
2872 	__be32 *p;
2873 
2874 	if (bmval2) {
2875 		p = xdr_reserve_space(xdr, XDR_UNIT * 4);
2876 		if (!p)
2877 			goto out_resource;
2878 		*p++ = cpu_to_be32(3);
2879 		*p++ = cpu_to_be32(bmval0);
2880 		*p++ = cpu_to_be32(bmval1);
2881 		*p++ = cpu_to_be32(bmval2);
2882 	} else if (bmval1) {
2883 		p = xdr_reserve_space(xdr, XDR_UNIT * 3);
2884 		if (!p)
2885 			goto out_resource;
2886 		*p++ = cpu_to_be32(2);
2887 		*p++ = cpu_to_be32(bmval0);
2888 		*p++ = cpu_to_be32(bmval1);
2889 	} else {
2890 		p = xdr_reserve_space(xdr, XDR_UNIT * 2);
2891 		if (!p)
2892 			goto out_resource;
2893 		*p++ = cpu_to_be32(1);
2894 		*p++ = cpu_to_be32(bmval0);
2895 	}
2896 
2897 	return nfs_ok;
2898 out_resource:
2899 	return nfserr_resource;
2900 }
2901 
2902 struct nfsd4_fattr_args {
2903 	struct svc_rqst		*rqstp;
2904 	struct svc_fh		*fhp;
2905 	struct svc_export	*exp;
2906 	struct dentry		*dentry;
2907 	struct kstat		stat;
2908 	struct kstatfs		statfs;
2909 	struct nfs4_acl		*acl;
2910 	u64			size;
2911 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2912 	void			*context;
2913 	int			contextlen;
2914 #endif
2915 	u32			rdattr_err;
2916 	bool			contextsupport;
2917 	bool			ignore_crossmnt;
2918 };
2919 
2920 typedef __be32(*nfsd4_enc_attr)(struct xdr_stream *xdr,
2921 				const struct nfsd4_fattr_args *args);
2922 
2923 static __be32 nfsd4_encode_fattr4__noop(struct xdr_stream *xdr,
2924 					const struct nfsd4_fattr_args *args)
2925 {
2926 	return nfs_ok;
2927 }
2928 
2929 static __be32 nfsd4_encode_fattr4__true(struct xdr_stream *xdr,
2930 					const struct nfsd4_fattr_args *args)
2931 {
2932 	return nfsd4_encode_bool(xdr, true);
2933 }
2934 
2935 static __be32 nfsd4_encode_fattr4__false(struct xdr_stream *xdr,
2936 					 const struct nfsd4_fattr_args *args)
2937 {
2938 	return nfsd4_encode_bool(xdr, false);
2939 }
2940 
2941 static __be32 nfsd4_encode_fattr4_supported_attrs(struct xdr_stream *xdr,
2942 						  const struct nfsd4_fattr_args *args)
2943 {
2944 	struct nfsd4_compoundres *resp = args->rqstp->rq_resp;
2945 	u32 minorversion = resp->cstate.minorversion;
2946 	u32 supp[3];
2947 
2948 	memcpy(supp, nfsd_suppattrs[minorversion], sizeof(supp));
2949 	if (!IS_POSIXACL(d_inode(args->dentry)))
2950 		supp[0] &= ~FATTR4_WORD0_ACL;
2951 	if (!args->contextsupport)
2952 		supp[2] &= ~FATTR4_WORD2_SECURITY_LABEL;
2953 
2954 	return nfsd4_encode_bitmap4(xdr, supp[0], supp[1], supp[2]);
2955 }
2956 
2957 static __be32 nfsd4_encode_fattr4_type(struct xdr_stream *xdr,
2958 				       const struct nfsd4_fattr_args *args)
2959 {
2960 	__be32 *p;
2961 
2962 	p = xdr_reserve_space(xdr, XDR_UNIT);
2963 	if (!p)
2964 		return nfserr_resource;
2965 
2966 	switch (args->stat.mode & S_IFMT) {
2967 	case S_IFIFO:
2968 		*p = cpu_to_be32(NF4FIFO);
2969 		break;
2970 	case S_IFCHR:
2971 		*p = cpu_to_be32(NF4CHR);
2972 		break;
2973 	case S_IFDIR:
2974 		*p = cpu_to_be32(NF4DIR);
2975 		break;
2976 	case S_IFBLK:
2977 		*p = cpu_to_be32(NF4BLK);
2978 		break;
2979 	case S_IFLNK:
2980 		*p = cpu_to_be32(NF4LNK);
2981 		break;
2982 	case S_IFREG:
2983 		*p = cpu_to_be32(NF4REG);
2984 		break;
2985 	case S_IFSOCK:
2986 		*p = cpu_to_be32(NF4SOCK);
2987 		break;
2988 	default:
2989 		return nfserr_serverfault;
2990 	}
2991 
2992 	return nfs_ok;
2993 }
2994 
2995 static __be32 nfsd4_encode_fattr4_fh_expire_type(struct xdr_stream *xdr,
2996 						 const struct nfsd4_fattr_args *args)
2997 {
2998 	u32 mask;
2999 
3000 	mask = NFS4_FH_PERSISTENT;
3001 	if (!(args->exp->ex_flags & NFSEXP_NOSUBTREECHECK))
3002 		mask |= NFS4_FH_VOL_RENAME;
3003 	return nfsd4_encode_uint32_t(xdr, mask);
3004 }
3005 
3006 static __be32 nfsd4_encode_fattr4_change(struct xdr_stream *xdr,
3007 					 const struct nfsd4_fattr_args *args)
3008 {
3009 	const struct svc_export *exp = args->exp;
3010 	u64 c;
3011 
3012 	if (unlikely(exp->ex_flags & NFSEXP_V4ROOT)) {
3013 		u32 flush_time = convert_to_wallclock(exp->cd->flush_time);
3014 
3015 		if (xdr_stream_encode_u32(xdr, flush_time) != XDR_UNIT)
3016 			return nfserr_resource;
3017 		if (xdr_stream_encode_u32(xdr, 0) != XDR_UNIT)
3018 			return nfserr_resource;
3019 		return nfs_ok;
3020 	}
3021 
3022 	c = nfsd4_change_attribute(&args->stat, d_inode(args->dentry));
3023 	return nfsd4_encode_changeid4(xdr, c);
3024 }
3025 
3026 static __be32 nfsd4_encode_fattr4_size(struct xdr_stream *xdr,
3027 				       const struct nfsd4_fattr_args *args)
3028 {
3029 	return nfsd4_encode_uint64_t(xdr, args->size);
3030 }
3031 
3032 static __be32 nfsd4_encode_fattr4_fsid(struct xdr_stream *xdr,
3033 				       const struct nfsd4_fattr_args *args)
3034 {
3035 	__be32 *p;
3036 
3037 	p = xdr_reserve_space(xdr, XDR_UNIT * 2 + XDR_UNIT * 2);
3038 	if (!p)
3039 		return nfserr_resource;
3040 
3041 	if (unlikely(args->exp->ex_fslocs.migrated)) {
3042 		p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
3043 		xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
3044 		return nfs_ok;
3045 	}
3046 	switch (fsid_source(args->fhp)) {
3047 	case FSIDSOURCE_FSID:
3048 		p = xdr_encode_hyper(p, (u64)args->exp->ex_fsid);
3049 		xdr_encode_hyper(p, (u64)0);
3050 		break;
3051 	case FSIDSOURCE_DEV:
3052 		*p++ = xdr_zero;
3053 		*p++ = cpu_to_be32(MAJOR(args->stat.dev));
3054 		*p++ = xdr_zero;
3055 		*p   = cpu_to_be32(MINOR(args->stat.dev));
3056 		break;
3057 	case FSIDSOURCE_UUID:
3058 		xdr_encode_opaque_fixed(p, args->exp->ex_uuid, EX_UUID_LEN);
3059 		break;
3060 	}
3061 
3062 	return nfs_ok;
3063 }
3064 
3065 static __be32 nfsd4_encode_fattr4_lease_time(struct xdr_stream *xdr,
3066 					     const struct nfsd4_fattr_args *args)
3067 {
3068 	struct nfsd_net *nn = net_generic(SVC_NET(args->rqstp), nfsd_net_id);
3069 
3070 	return nfsd4_encode_nfs_lease4(xdr, nn->nfsd4_lease);
3071 }
3072 
3073 static __be32 nfsd4_encode_fattr4_rdattr_error(struct xdr_stream *xdr,
3074 					       const struct nfsd4_fattr_args *args)
3075 {
3076 	return nfsd4_encode_uint32_t(xdr, args->rdattr_err);
3077 }
3078 
3079 static __be32 nfsd4_encode_fattr4_aclsupport(struct xdr_stream *xdr,
3080 					     const struct nfsd4_fattr_args *args)
3081 {
3082 	u32 mask;
3083 
3084 	mask = 0;
3085 	if (IS_POSIXACL(d_inode(args->dentry)))
3086 		mask = ACL4_SUPPORT_ALLOW_ACL | ACL4_SUPPORT_DENY_ACL;
3087 	return nfsd4_encode_uint32_t(xdr, mask);
3088 }
3089 
3090 static __be32 nfsd4_encode_fattr4_acl(struct xdr_stream *xdr,
3091 				      const struct nfsd4_fattr_args *args)
3092 {
3093 	struct nfs4_acl *acl = args->acl;
3094 	struct nfs4_ace *ace;
3095 	__be32 status;
3096 
3097 	/* nfsace4<> */
3098 	if (!acl) {
3099 		if (xdr_stream_encode_u32(xdr, 0) != XDR_UNIT)
3100 			return nfserr_resource;
3101 	} else {
3102 		if (xdr_stream_encode_u32(xdr, acl->naces) != XDR_UNIT)
3103 			return nfserr_resource;
3104 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
3105 			status = nfsd4_encode_nfsace4(xdr, args->rqstp, ace);
3106 			if (status != nfs_ok)
3107 				return status;
3108 		}
3109 	}
3110 	return nfs_ok;
3111 }
3112 
3113 static __be32 nfsd4_encode_fattr4_filehandle(struct xdr_stream *xdr,
3114 					     const struct nfsd4_fattr_args *args)
3115 {
3116 	return nfsd4_encode_nfs_fh4(xdr, &args->fhp->fh_handle);
3117 }
3118 
3119 static __be32 nfsd4_encode_fattr4_fileid(struct xdr_stream *xdr,
3120 					 const struct nfsd4_fattr_args *args)
3121 {
3122 	return nfsd4_encode_uint64_t(xdr, args->stat.ino);
3123 }
3124 
3125 static __be32 nfsd4_encode_fattr4_files_avail(struct xdr_stream *xdr,
3126 					      const struct nfsd4_fattr_args *args)
3127 {
3128 	return nfsd4_encode_uint64_t(xdr, args->statfs.f_ffree);
3129 }
3130 
3131 static __be32 nfsd4_encode_fattr4_files_free(struct xdr_stream *xdr,
3132 					     const struct nfsd4_fattr_args *args)
3133 {
3134 	return nfsd4_encode_uint64_t(xdr, args->statfs.f_ffree);
3135 }
3136 
3137 static __be32 nfsd4_encode_fattr4_files_total(struct xdr_stream *xdr,
3138 					      const struct nfsd4_fattr_args *args)
3139 {
3140 	return nfsd4_encode_uint64_t(xdr, args->statfs.f_files);
3141 }
3142 
3143 static __be32 nfsd4_encode_fattr4_fs_locations(struct xdr_stream *xdr,
3144 					       const struct nfsd4_fattr_args *args)
3145 {
3146 	return nfsd4_encode_fs_locations4(xdr, args->rqstp, args->exp);
3147 }
3148 
3149 static __be32 nfsd4_encode_fattr4_maxfilesize(struct xdr_stream *xdr,
3150 					      const struct nfsd4_fattr_args *args)
3151 {
3152 	struct super_block *sb = args->exp->ex_path.mnt->mnt_sb;
3153 
3154 	return nfsd4_encode_uint64_t(xdr, sb->s_maxbytes);
3155 }
3156 
3157 static __be32 nfsd4_encode_fattr4_maxlink(struct xdr_stream *xdr,
3158 					  const struct nfsd4_fattr_args *args)
3159 {
3160 	return nfsd4_encode_uint32_t(xdr, 255);
3161 }
3162 
3163 static __be32 nfsd4_encode_fattr4_maxname(struct xdr_stream *xdr,
3164 					  const struct nfsd4_fattr_args *args)
3165 {
3166 	return nfsd4_encode_uint32_t(xdr, args->statfs.f_namelen);
3167 }
3168 
3169 static __be32 nfsd4_encode_fattr4_maxread(struct xdr_stream *xdr,
3170 					  const struct nfsd4_fattr_args *args)
3171 {
3172 	return nfsd4_encode_uint64_t(xdr, svc_max_payload(args->rqstp));
3173 }
3174 
3175 static __be32 nfsd4_encode_fattr4_maxwrite(struct xdr_stream *xdr,
3176 					   const struct nfsd4_fattr_args *args)
3177 {
3178 	return nfsd4_encode_uint64_t(xdr, svc_max_payload(args->rqstp));
3179 }
3180 
3181 static __be32 nfsd4_encode_fattr4_mode(struct xdr_stream *xdr,
3182 				       const struct nfsd4_fattr_args *args)
3183 {
3184 	return nfsd4_encode_mode4(xdr, args->stat.mode & S_IALLUGO);
3185 }
3186 
3187 static __be32 nfsd4_encode_fattr4_numlinks(struct xdr_stream *xdr,
3188 					   const struct nfsd4_fattr_args *args)
3189 {
3190 	return nfsd4_encode_uint32_t(xdr, args->stat.nlink);
3191 }
3192 
3193 static __be32 nfsd4_encode_fattr4_owner(struct xdr_stream *xdr,
3194 					const struct nfsd4_fattr_args *args)
3195 {
3196 	return nfsd4_encode_user(xdr, args->rqstp, args->stat.uid);
3197 }
3198 
3199 static __be32 nfsd4_encode_fattr4_owner_group(struct xdr_stream *xdr,
3200 					      const struct nfsd4_fattr_args *args)
3201 {
3202 	return nfsd4_encode_group(xdr, args->rqstp, args->stat.gid);
3203 }
3204 
3205 static __be32 nfsd4_encode_fattr4_rawdev(struct xdr_stream *xdr,
3206 					 const struct nfsd4_fattr_args *args)
3207 {
3208 	return nfsd4_encode_specdata4(xdr, MAJOR(args->stat.rdev),
3209 				      MINOR(args->stat.rdev));
3210 }
3211 
3212 static __be32 nfsd4_encode_fattr4_space_avail(struct xdr_stream *xdr,
3213 					      const struct nfsd4_fattr_args *args)
3214 {
3215 	u64 avail = (u64)args->statfs.f_bavail * (u64)args->statfs.f_bsize;
3216 
3217 	return nfsd4_encode_uint64_t(xdr, avail);
3218 }
3219 
3220 static __be32 nfsd4_encode_fattr4_space_free(struct xdr_stream *xdr,
3221 					     const struct nfsd4_fattr_args *args)
3222 {
3223 	u64 free = (u64)args->statfs.f_bfree * (u64)args->statfs.f_bsize;
3224 
3225 	return nfsd4_encode_uint64_t(xdr, free);
3226 }
3227 
3228 static __be32 nfsd4_encode_fattr4_space_total(struct xdr_stream *xdr,
3229 					      const struct nfsd4_fattr_args *args)
3230 {
3231 	u64 total = (u64)args->statfs.f_blocks * (u64)args->statfs.f_bsize;
3232 
3233 	return nfsd4_encode_uint64_t(xdr, total);
3234 }
3235 
3236 static __be32 nfsd4_encode_fattr4_space_used(struct xdr_stream *xdr,
3237 					     const struct nfsd4_fattr_args *args)
3238 {
3239 	return nfsd4_encode_uint64_t(xdr, (u64)args->stat.blocks << 9);
3240 }
3241 
3242 static __be32 nfsd4_encode_fattr4_time_access(struct xdr_stream *xdr,
3243 					      const struct nfsd4_fattr_args *args)
3244 {
3245 	return nfsd4_encode_nfstime4(xdr, &args->stat.atime);
3246 }
3247 
3248 static __be32 nfsd4_encode_fattr4_time_create(struct xdr_stream *xdr,
3249 					      const struct nfsd4_fattr_args *args)
3250 {
3251 	return nfsd4_encode_nfstime4(xdr, &args->stat.btime);
3252 }
3253 
3254 /*
3255  * ctime (in NFSv4, time_metadata) is not writeable, and the client
3256  * doesn't really care what resolution could theoretically be stored by
3257  * the filesystem.
3258  *
3259  * The client cares how close together changes can be while still
3260  * guaranteeing ctime changes.  For most filesystems (which have
3261  * timestamps with nanosecond fields) that is limited by the resolution
3262  * of the time returned from current_time() (which I'm assuming to be
3263  * 1/HZ).
3264  */
3265 static __be32 nfsd4_encode_fattr4_time_delta(struct xdr_stream *xdr,
3266 					     const struct nfsd4_fattr_args *args)
3267 {
3268 	const struct inode *inode = d_inode(args->dentry);
3269 	u32 ns = max_t(u32, NSEC_PER_SEC/HZ, inode->i_sb->s_time_gran);
3270 	struct timespec64 ts = ns_to_timespec64(ns);
3271 
3272 	return nfsd4_encode_nfstime4(xdr, &ts);
3273 }
3274 
3275 static __be32 nfsd4_encode_fattr4_time_metadata(struct xdr_stream *xdr,
3276 						const struct nfsd4_fattr_args *args)
3277 {
3278 	return nfsd4_encode_nfstime4(xdr, &args->stat.ctime);
3279 }
3280 
3281 static __be32 nfsd4_encode_fattr4_time_modify(struct xdr_stream *xdr,
3282 					      const struct nfsd4_fattr_args *args)
3283 {
3284 	return nfsd4_encode_nfstime4(xdr, &args->stat.mtime);
3285 }
3286 
3287 static __be32 nfsd4_encode_fattr4_mounted_on_fileid(struct xdr_stream *xdr,
3288 						    const struct nfsd4_fattr_args *args)
3289 {
3290 	u64 ino;
3291 	int err;
3292 
3293 	if (!args->ignore_crossmnt &&
3294 	    args->dentry == args->exp->ex_path.mnt->mnt_root) {
3295 		err = nfsd4_get_mounted_on_ino(args->exp, &ino);
3296 		if (err)
3297 			return nfserrno(err);
3298 	} else
3299 		ino = args->stat.ino;
3300 
3301 	return nfsd4_encode_uint64_t(xdr, ino);
3302 }
3303 
3304 #ifdef CONFIG_NFSD_PNFS
3305 
3306 static __be32 nfsd4_encode_fattr4_fs_layout_types(struct xdr_stream *xdr,
3307 						  const struct nfsd4_fattr_args *args)
3308 {
3309 	unsigned long mask = args->exp->ex_layout_types;
3310 	int i;
3311 
3312 	/* Hamming weight of @mask is the number of layout types to return */
3313 	if (xdr_stream_encode_u32(xdr, hweight_long(mask)) != XDR_UNIT)
3314 		return nfserr_resource;
3315 	for (i = LAYOUT_NFSV4_1_FILES; i < LAYOUT_TYPE_MAX; ++i)
3316 		if (mask & BIT(i)) {
3317 			/* layouttype4 */
3318 			if (xdr_stream_encode_u32(xdr, i) != XDR_UNIT)
3319 				return nfserr_resource;
3320 		}
3321 	return nfs_ok;
3322 }
3323 
3324 static __be32 nfsd4_encode_fattr4_layout_types(struct xdr_stream *xdr,
3325 					       const struct nfsd4_fattr_args *args)
3326 {
3327 	unsigned long mask = args->exp->ex_layout_types;
3328 	int i;
3329 
3330 	/* Hamming weight of @mask is the number of layout types to return */
3331 	if (xdr_stream_encode_u32(xdr, hweight_long(mask)) != XDR_UNIT)
3332 		return nfserr_resource;
3333 	for (i = LAYOUT_NFSV4_1_FILES; i < LAYOUT_TYPE_MAX; ++i)
3334 		if (mask & BIT(i)) {
3335 			/* layouttype4 */
3336 			if (xdr_stream_encode_u32(xdr, i) != XDR_UNIT)
3337 				return nfserr_resource;
3338 		}
3339 	return nfs_ok;
3340 }
3341 
3342 static __be32 nfsd4_encode_fattr4_layout_blksize(struct xdr_stream *xdr,
3343 						 const struct nfsd4_fattr_args *args)
3344 {
3345 	return nfsd4_encode_uint32_t(xdr, args->stat.blksize);
3346 }
3347 
3348 #endif
3349 
3350 static __be32 nfsd4_encode_fattr4_suppattr_exclcreat(struct xdr_stream *xdr,
3351 						     const struct nfsd4_fattr_args *args)
3352 {
3353 	struct nfsd4_compoundres *resp = args->rqstp->rq_resp;
3354 	u32 supp[3];
3355 
3356 	memcpy(supp, nfsd_suppattrs[resp->cstate.minorversion], sizeof(supp));
3357 	supp[0] &= NFSD_SUPPATTR_EXCLCREAT_WORD0;
3358 	supp[1] &= NFSD_SUPPATTR_EXCLCREAT_WORD1;
3359 	supp[2] &= NFSD_SUPPATTR_EXCLCREAT_WORD2;
3360 
3361 	return nfsd4_encode_bitmap4(xdr, supp[0], supp[1], supp[2]);
3362 }
3363 
3364 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
3365 static __be32 nfsd4_encode_fattr4_sec_label(struct xdr_stream *xdr,
3366 					    const struct nfsd4_fattr_args *args)
3367 {
3368 	return nfsd4_encode_security_label(xdr, args->rqstp,
3369 					   args->context, args->contextlen);
3370 }
3371 #endif
3372 
3373 static __be32 nfsd4_encode_fattr4_xattr_support(struct xdr_stream *xdr,
3374 						const struct nfsd4_fattr_args *args)
3375 {
3376 	int err = xattr_supports_user_prefix(d_inode(args->dentry));
3377 
3378 	return nfsd4_encode_bool(xdr, err == 0);
3379 }
3380 
3381 static const nfsd4_enc_attr nfsd4_enc_fattr4_encode_ops[] = {
3382 	[FATTR4_SUPPORTED_ATTRS]	= nfsd4_encode_fattr4_supported_attrs,
3383 	[FATTR4_TYPE]			= nfsd4_encode_fattr4_type,
3384 	[FATTR4_FH_EXPIRE_TYPE]		= nfsd4_encode_fattr4_fh_expire_type,
3385 	[FATTR4_CHANGE]			= nfsd4_encode_fattr4_change,
3386 	[FATTR4_SIZE]			= nfsd4_encode_fattr4_size,
3387 	[FATTR4_LINK_SUPPORT]		= nfsd4_encode_fattr4__true,
3388 	[FATTR4_SYMLINK_SUPPORT]	= nfsd4_encode_fattr4__true,
3389 	[FATTR4_NAMED_ATTR]		= nfsd4_encode_fattr4__false,
3390 	[FATTR4_FSID]			= nfsd4_encode_fattr4_fsid,
3391 	[FATTR4_UNIQUE_HANDLES]		= nfsd4_encode_fattr4__true,
3392 	[FATTR4_LEASE_TIME]		= nfsd4_encode_fattr4_lease_time,
3393 	[FATTR4_RDATTR_ERROR]		= nfsd4_encode_fattr4_rdattr_error,
3394 	[FATTR4_ACL]			= nfsd4_encode_fattr4_acl,
3395 	[FATTR4_ACLSUPPORT]		= nfsd4_encode_fattr4_aclsupport,
3396 	[FATTR4_ARCHIVE]		= nfsd4_encode_fattr4__noop,
3397 	[FATTR4_CANSETTIME]		= nfsd4_encode_fattr4__true,
3398 	[FATTR4_CASE_INSENSITIVE]	= nfsd4_encode_fattr4__false,
3399 	[FATTR4_CASE_PRESERVING]	= nfsd4_encode_fattr4__true,
3400 	[FATTR4_CHOWN_RESTRICTED]	= nfsd4_encode_fattr4__true,
3401 	[FATTR4_FILEHANDLE]		= nfsd4_encode_fattr4_filehandle,
3402 	[FATTR4_FILEID]			= nfsd4_encode_fattr4_fileid,
3403 	[FATTR4_FILES_AVAIL]		= nfsd4_encode_fattr4_files_avail,
3404 	[FATTR4_FILES_FREE]		= nfsd4_encode_fattr4_files_free,
3405 	[FATTR4_FILES_TOTAL]		= nfsd4_encode_fattr4_files_total,
3406 	[FATTR4_FS_LOCATIONS]		= nfsd4_encode_fattr4_fs_locations,
3407 	[FATTR4_HIDDEN]			= nfsd4_encode_fattr4__noop,
3408 	[FATTR4_HOMOGENEOUS]		= nfsd4_encode_fattr4__true,
3409 	[FATTR4_MAXFILESIZE]		= nfsd4_encode_fattr4_maxfilesize,
3410 	[FATTR4_MAXLINK]		= nfsd4_encode_fattr4_maxlink,
3411 	[FATTR4_MAXNAME]		= nfsd4_encode_fattr4_maxname,
3412 	[FATTR4_MAXREAD]		= nfsd4_encode_fattr4_maxread,
3413 	[FATTR4_MAXWRITE]		= nfsd4_encode_fattr4_maxwrite,
3414 	[FATTR4_MIMETYPE]		= nfsd4_encode_fattr4__noop,
3415 	[FATTR4_MODE]			= nfsd4_encode_fattr4_mode,
3416 	[FATTR4_NO_TRUNC]		= nfsd4_encode_fattr4__true,
3417 	[FATTR4_NUMLINKS]		= nfsd4_encode_fattr4_numlinks,
3418 	[FATTR4_OWNER]			= nfsd4_encode_fattr4_owner,
3419 	[FATTR4_OWNER_GROUP]		= nfsd4_encode_fattr4_owner_group,
3420 	[FATTR4_QUOTA_AVAIL_HARD]	= nfsd4_encode_fattr4__noop,
3421 	[FATTR4_QUOTA_AVAIL_SOFT]	= nfsd4_encode_fattr4__noop,
3422 	[FATTR4_QUOTA_USED]		= nfsd4_encode_fattr4__noop,
3423 	[FATTR4_RAWDEV]			= nfsd4_encode_fattr4_rawdev,
3424 	[FATTR4_SPACE_AVAIL]		= nfsd4_encode_fattr4_space_avail,
3425 	[FATTR4_SPACE_FREE]		= nfsd4_encode_fattr4_space_free,
3426 	[FATTR4_SPACE_TOTAL]		= nfsd4_encode_fattr4_space_total,
3427 	[FATTR4_SPACE_USED]		= nfsd4_encode_fattr4_space_used,
3428 	[FATTR4_SYSTEM]			= nfsd4_encode_fattr4__noop,
3429 	[FATTR4_TIME_ACCESS]		= nfsd4_encode_fattr4_time_access,
3430 	[FATTR4_TIME_ACCESS_SET]	= nfsd4_encode_fattr4__noop,
3431 	[FATTR4_TIME_BACKUP]		= nfsd4_encode_fattr4__noop,
3432 	[FATTR4_TIME_CREATE]		= nfsd4_encode_fattr4_time_create,
3433 	[FATTR4_TIME_DELTA]		= nfsd4_encode_fattr4_time_delta,
3434 	[FATTR4_TIME_METADATA]		= nfsd4_encode_fattr4_time_metadata,
3435 	[FATTR4_TIME_MODIFY]		= nfsd4_encode_fattr4_time_modify,
3436 	[FATTR4_TIME_MODIFY_SET]	= nfsd4_encode_fattr4__noop,
3437 	[FATTR4_MOUNTED_ON_FILEID]	= nfsd4_encode_fattr4_mounted_on_fileid,
3438 	[FATTR4_DIR_NOTIF_DELAY]	= nfsd4_encode_fattr4__noop,
3439 	[FATTR4_DIRENT_NOTIF_DELAY]	= nfsd4_encode_fattr4__noop,
3440 	[FATTR4_DACL]			= nfsd4_encode_fattr4__noop,
3441 	[FATTR4_SACL]			= nfsd4_encode_fattr4__noop,
3442 	[FATTR4_CHANGE_POLICY]		= nfsd4_encode_fattr4__noop,
3443 	[FATTR4_FS_STATUS]		= nfsd4_encode_fattr4__noop,
3444 
3445 #ifdef CONFIG_NFSD_PNFS
3446 	[FATTR4_FS_LAYOUT_TYPES]	= nfsd4_encode_fattr4_fs_layout_types,
3447 	[FATTR4_LAYOUT_HINT]		= nfsd4_encode_fattr4__noop,
3448 	[FATTR4_LAYOUT_TYPES]		= nfsd4_encode_fattr4_layout_types,
3449 	[FATTR4_LAYOUT_BLKSIZE]		= nfsd4_encode_fattr4_layout_blksize,
3450 	[FATTR4_LAYOUT_ALIGNMENT]	= nfsd4_encode_fattr4__noop,
3451 #else
3452 	[FATTR4_FS_LAYOUT_TYPES]	= nfsd4_encode_fattr4__noop,
3453 	[FATTR4_LAYOUT_HINT]		= nfsd4_encode_fattr4__noop,
3454 	[FATTR4_LAYOUT_TYPES]		= nfsd4_encode_fattr4__noop,
3455 	[FATTR4_LAYOUT_BLKSIZE]		= nfsd4_encode_fattr4__noop,
3456 	[FATTR4_LAYOUT_ALIGNMENT]	= nfsd4_encode_fattr4__noop,
3457 #endif
3458 
3459 	[FATTR4_FS_LOCATIONS_INFO]	= nfsd4_encode_fattr4__noop,
3460 	[FATTR4_MDSTHRESHOLD]		= nfsd4_encode_fattr4__noop,
3461 	[FATTR4_RETENTION_GET]		= nfsd4_encode_fattr4__noop,
3462 	[FATTR4_RETENTION_SET]		= nfsd4_encode_fattr4__noop,
3463 	[FATTR4_RETENTEVT_GET]		= nfsd4_encode_fattr4__noop,
3464 	[FATTR4_RETENTEVT_SET]		= nfsd4_encode_fattr4__noop,
3465 	[FATTR4_RETENTION_HOLD]		= nfsd4_encode_fattr4__noop,
3466 	[FATTR4_MODE_SET_MASKED]	= nfsd4_encode_fattr4__noop,
3467 	[FATTR4_SUPPATTR_EXCLCREAT]	= nfsd4_encode_fattr4_suppattr_exclcreat,
3468 	[FATTR4_FS_CHARSET_CAP]		= nfsd4_encode_fattr4__noop,
3469 	[FATTR4_CLONE_BLKSIZE]		= nfsd4_encode_fattr4__noop,
3470 	[FATTR4_SPACE_FREED]		= nfsd4_encode_fattr4__noop,
3471 	[FATTR4_CHANGE_ATTR_TYPE]	= nfsd4_encode_fattr4__noop,
3472 
3473 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
3474 	[FATTR4_SEC_LABEL]		= nfsd4_encode_fattr4_sec_label,
3475 #else
3476 	[FATTR4_SEC_LABEL]		= nfsd4_encode_fattr4__noop,
3477 #endif
3478 
3479 	[FATTR4_MODE_UMASK]		= nfsd4_encode_fattr4__noop,
3480 	[FATTR4_XATTR_SUPPORT]		= nfsd4_encode_fattr4_xattr_support,
3481 };
3482 
3483 /*
3484  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
3485  * ourselves.
3486  */
3487 static __be32
3488 nfsd4_encode_fattr4(struct svc_rqst *rqstp, struct xdr_stream *xdr,
3489 		    struct svc_fh *fhp, struct svc_export *exp,
3490 		    struct dentry *dentry, const u32 *bmval,
3491 		    int ignore_crossmnt)
3492 {
3493 	struct nfsd4_fattr_args args;
3494 	struct svc_fh *tempfh = NULL;
3495 	int starting_len = xdr->buf->len;
3496 	__be32 *attrlen_p, status;
3497 	int attrlen_offset;
3498 	int err;
3499 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
3500 	u32 minorversion = resp->cstate.minorversion;
3501 	struct path path = {
3502 		.mnt	= exp->ex_path.mnt,
3503 		.dentry	= dentry,
3504 	};
3505 	union {
3506 		u32		attrmask[3];
3507 		unsigned long	mask[2];
3508 	} u;
3509 	unsigned long bit;
3510 
3511 	WARN_ON_ONCE(bmval[1] & NFSD_WRITEONLY_ATTRS_WORD1);
3512 	WARN_ON_ONCE(!nfsd_attrs_supported(minorversion, bmval));
3513 
3514 	args.rqstp = rqstp;
3515 	args.exp = exp;
3516 	args.dentry = dentry;
3517 	args.ignore_crossmnt = (ignore_crossmnt != 0);
3518 
3519 	/*
3520 	 * Make a local copy of the attribute bitmap that can be modified.
3521 	 */
3522 	memset(&u, 0, sizeof(u));
3523 	u.attrmask[0] = bmval[0];
3524 	u.attrmask[1] = bmval[1];
3525 	u.attrmask[2] = bmval[2];
3526 
3527 	args.rdattr_err = 0;
3528 	if (exp->ex_fslocs.migrated) {
3529 		status = fattr_handle_absent_fs(&u.attrmask[0], &u.attrmask[1],
3530 						&u.attrmask[2], &args.rdattr_err);
3531 		if (status)
3532 			goto out;
3533 	}
3534 	args.size = 0;
3535 	if (u.attrmask[0] & (FATTR4_WORD0_CHANGE | FATTR4_WORD0_SIZE)) {
3536 		status = nfsd4_deleg_getattr_conflict(rqstp, d_inode(dentry));
3537 		if (status)
3538 			goto out;
3539 	}
3540 
3541 	err = vfs_getattr(&path, &args.stat,
3542 			  STATX_BASIC_STATS | STATX_BTIME | STATX_CHANGE_COOKIE,
3543 			  AT_STATX_SYNC_AS_STAT);
3544 	if (err)
3545 		goto out_nfserr;
3546 	args.size = args.stat.size;
3547 
3548 	if (!(args.stat.result_mask & STATX_BTIME))
3549 		/* underlying FS does not offer btime so we can't share it */
3550 		u.attrmask[1] &= ~FATTR4_WORD1_TIME_CREATE;
3551 	if ((u.attrmask[0] & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
3552 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
3553 	    (u.attrmask[1] & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
3554 		       FATTR4_WORD1_SPACE_TOTAL))) {
3555 		err = vfs_statfs(&path, &args.statfs);
3556 		if (err)
3557 			goto out_nfserr;
3558 	}
3559 	if ((u.attrmask[0] & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) &&
3560 	    !fhp) {
3561 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
3562 		status = nfserr_jukebox;
3563 		if (!tempfh)
3564 			goto out;
3565 		fh_init(tempfh, NFS4_FHSIZE);
3566 		status = fh_compose(tempfh, exp, dentry, NULL);
3567 		if (status)
3568 			goto out;
3569 		args.fhp = tempfh;
3570 	} else
3571 		args.fhp = fhp;
3572 
3573 	args.acl = NULL;
3574 	if (u.attrmask[0] & FATTR4_WORD0_ACL) {
3575 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &args.acl);
3576 		if (err == -EOPNOTSUPP)
3577 			u.attrmask[0] &= ~FATTR4_WORD0_ACL;
3578 		else if (err == -EINVAL) {
3579 			status = nfserr_attrnotsupp;
3580 			goto out;
3581 		} else if (err != 0)
3582 			goto out_nfserr;
3583 	}
3584 
3585 	args.contextsupport = false;
3586 
3587 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
3588 	args.context = NULL;
3589 	if ((u.attrmask[2] & FATTR4_WORD2_SECURITY_LABEL) ||
3590 	     u.attrmask[0] & FATTR4_WORD0_SUPPORTED_ATTRS) {
3591 		if (exp->ex_flags & NFSEXP_SECURITY_LABEL)
3592 			err = security_inode_getsecctx(d_inode(dentry),
3593 						&args.context, &args.contextlen);
3594 		else
3595 			err = -EOPNOTSUPP;
3596 		args.contextsupport = (err == 0);
3597 		if (u.attrmask[2] & FATTR4_WORD2_SECURITY_LABEL) {
3598 			if (err == -EOPNOTSUPP)
3599 				u.attrmask[2] &= ~FATTR4_WORD2_SECURITY_LABEL;
3600 			else if (err)
3601 				goto out_nfserr;
3602 		}
3603 	}
3604 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
3605 
3606 	/* attrmask */
3607 	status = nfsd4_encode_bitmap4(xdr, u.attrmask[0],
3608 				      u.attrmask[1], u.attrmask[2]);
3609 	if (status)
3610 		goto out;
3611 
3612 	/* attr_vals */
3613 	attrlen_offset = xdr->buf->len;
3614 	attrlen_p = xdr_reserve_space(xdr, XDR_UNIT);
3615 	if (!attrlen_p)
3616 		goto out_resource;
3617 	for_each_set_bit(bit, (const unsigned long *)&u.mask,
3618 			 ARRAY_SIZE(nfsd4_enc_fattr4_encode_ops)) {
3619 		status = nfsd4_enc_fattr4_encode_ops[bit](xdr, &args);
3620 		if (status != nfs_ok)
3621 			goto out;
3622 	}
3623 	*attrlen_p = cpu_to_be32(xdr->buf->len - attrlen_offset - XDR_UNIT);
3624 	status = nfs_ok;
3625 
3626 out:
3627 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
3628 	if (args.context)
3629 		security_release_secctx(args.context, args.contextlen);
3630 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
3631 	kfree(args.acl);
3632 	if (tempfh) {
3633 		fh_put(tempfh);
3634 		kfree(tempfh);
3635 	}
3636 	if (status)
3637 		xdr_truncate_encode(xdr, starting_len);
3638 	return status;
3639 out_nfserr:
3640 	status = nfserrno(err);
3641 	goto out;
3642 out_resource:
3643 	status = nfserr_resource;
3644 	goto out;
3645 }
3646 
3647 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
3648 				struct xdr_buf *buf, __be32 *p, int bytes)
3649 {
3650 	xdr->scratch.iov_len = 0;
3651 	memset(buf, 0, sizeof(struct xdr_buf));
3652 	buf->head[0].iov_base = p;
3653 	buf->head[0].iov_len = 0;
3654 	buf->len = 0;
3655 	xdr->buf = buf;
3656 	xdr->iov = buf->head;
3657 	xdr->p = p;
3658 	xdr->end = (void *)p + bytes;
3659 	buf->buflen = bytes;
3660 }
3661 
3662 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
3663 			struct svc_fh *fhp, struct svc_export *exp,
3664 			struct dentry *dentry, u32 *bmval,
3665 			struct svc_rqst *rqstp, int ignore_crossmnt)
3666 {
3667 	struct xdr_buf dummy;
3668 	struct xdr_stream xdr;
3669 	__be32 ret;
3670 
3671 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
3672 	ret = nfsd4_encode_fattr4(rqstp, &xdr, fhp, exp, dentry, bmval,
3673 				  ignore_crossmnt);
3674 	*p = xdr.p;
3675 	return ret;
3676 }
3677 
3678 /*
3679  * The buffer space for this field was reserved during a previous
3680  * call to nfsd4_encode_entry4().
3681  */
3682 static void nfsd4_encode_entry4_nfs_cookie4(const struct nfsd4_readdir *readdir,
3683 					    u64 offset)
3684 {
3685 	__be64 cookie = cpu_to_be64(offset);
3686 	struct xdr_stream *xdr = readdir->xdr;
3687 
3688 	if (!readdir->cookie_offset)
3689 		return;
3690 	write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset, &cookie,
3691 			       sizeof(cookie));
3692 }
3693 
3694 static inline int attributes_need_mount(u32 *bmval)
3695 {
3696 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
3697 		return 1;
3698 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
3699 		return 1;
3700 	return 0;
3701 }
3702 
3703 static __be32
3704 nfsd4_encode_entry4_fattr(struct nfsd4_readdir *cd, const char *name,
3705 			  int namlen)
3706 {
3707 	struct svc_export *exp = cd->rd_fhp->fh_export;
3708 	struct dentry *dentry;
3709 	__be32 nfserr;
3710 	int ignore_crossmnt = 0;
3711 
3712 	dentry = lookup_positive_unlocked(name, cd->rd_fhp->fh_dentry, namlen);
3713 	if (IS_ERR(dentry))
3714 		return nfserrno(PTR_ERR(dentry));
3715 
3716 	exp_get(exp);
3717 	/*
3718 	 * In the case of a mountpoint, the client may be asking for
3719 	 * attributes that are only properties of the underlying filesystem
3720 	 * as opposed to the cross-mounted file system. In such a case,
3721 	 * we will not follow the cross mount and will fill the attribtutes
3722 	 * directly from the mountpoint dentry.
3723 	 */
3724 	if (nfsd_mountpoint(dentry, exp)) {
3725 		int err;
3726 
3727 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
3728 				&& !attributes_need_mount(cd->rd_bmval)) {
3729 			ignore_crossmnt = 1;
3730 			goto out_encode;
3731 		}
3732 		/*
3733 		 * Why the heck aren't we just using nfsd_lookup??
3734 		 * Different "."/".." handling?  Something else?
3735 		 * At least, add a comment here to explain....
3736 		 */
3737 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
3738 		if (err) {
3739 			nfserr = nfserrno(err);
3740 			goto out_put;
3741 		}
3742 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
3743 		if (nfserr)
3744 			goto out_put;
3745 
3746 	}
3747 out_encode:
3748 	nfserr = nfsd4_encode_fattr4(cd->rd_rqstp, cd->xdr, NULL, exp, dentry,
3749 				     cd->rd_bmval, ignore_crossmnt);
3750 out_put:
3751 	dput(dentry);
3752 	exp_put(exp);
3753 	return nfserr;
3754 }
3755 
3756 static __be32
3757 nfsd4_encode_entry4_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
3758 {
3759 	__be32 status;
3760 
3761 	/* attrmask */
3762 	status = nfsd4_encode_bitmap4(xdr, FATTR4_WORD0_RDATTR_ERROR, 0, 0);
3763 	if (status != nfs_ok)
3764 		return status;
3765 	/* attr_vals */
3766 	if (xdr_stream_encode_u32(xdr, XDR_UNIT) != XDR_UNIT)
3767 		return nfserr_resource;
3768 	/* rdattr_error */
3769 	if (xdr_stream_encode_be32(xdr, nfserr) != XDR_UNIT)
3770 		return nfserr_resource;
3771 	return nfs_ok;
3772 }
3773 
3774 static int
3775 nfsd4_encode_entry4(void *ccdv, const char *name, int namlen,
3776 		    loff_t offset, u64 ino, unsigned int d_type)
3777 {
3778 	struct readdir_cd *ccd = ccdv;
3779 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
3780 	struct xdr_stream *xdr = cd->xdr;
3781 	int start_offset = xdr->buf->len;
3782 	int cookie_offset;
3783 	u32 name_and_cookie;
3784 	int entry_bytes;
3785 	__be32 nfserr = nfserr_toosmall;
3786 
3787 	/* In nfsv4, "." and ".." never make it onto the wire.. */
3788 	if (name && isdotent(name, namlen)) {
3789 		cd->common.err = nfs_ok;
3790 		return 0;
3791 	}
3792 
3793 	/* Encode the previous entry's cookie value */
3794 	nfsd4_encode_entry4_nfs_cookie4(cd, offset);
3795 
3796 	if (xdr_stream_encode_item_present(xdr) != XDR_UNIT)
3797 		goto fail;
3798 
3799 	/* Reserve send buffer space for this entry's cookie value. */
3800 	cookie_offset = xdr->buf->len;
3801 	if (nfsd4_encode_nfs_cookie4(xdr, OFFSET_MAX) != nfs_ok)
3802 		goto fail;
3803 	if (nfsd4_encode_component4(xdr, name, namlen) != nfs_ok)
3804 		goto fail;
3805 	nfserr = nfsd4_encode_entry4_fattr(cd, name, namlen);
3806 	switch (nfserr) {
3807 	case nfs_ok:
3808 		break;
3809 	case nfserr_resource:
3810 		nfserr = nfserr_toosmall;
3811 		goto fail;
3812 	case nfserr_noent:
3813 		xdr_truncate_encode(xdr, start_offset);
3814 		goto skip_entry;
3815 	case nfserr_jukebox:
3816 		/*
3817 		 * The pseudoroot should only display dentries that lead to
3818 		 * exports. If we get EJUKEBOX here, then we can't tell whether
3819 		 * this entry should be included. Just fail the whole READDIR
3820 		 * with NFS4ERR_DELAY in that case, and hope that the situation
3821 		 * will resolve itself by the client's next attempt.
3822 		 */
3823 		if (cd->rd_fhp->fh_export->ex_flags & NFSEXP_V4ROOT)
3824 			goto fail;
3825 		fallthrough;
3826 	default:
3827 		/*
3828 		 * If the client requested the RDATTR_ERROR attribute,
3829 		 * we stuff the error code into this attribute
3830 		 * and continue.  If this attribute was not requested,
3831 		 * then in accordance with the spec, we fail the
3832 		 * entire READDIR operation(!)
3833 		 */
3834 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
3835 			goto fail;
3836 		if (nfsd4_encode_entry4_rdattr_error(xdr, nfserr)) {
3837 			nfserr = nfserr_toosmall;
3838 			goto fail;
3839 		}
3840 	}
3841 	nfserr = nfserr_toosmall;
3842 	entry_bytes = xdr->buf->len - start_offset;
3843 	if (entry_bytes > cd->rd_maxcount)
3844 		goto fail;
3845 	cd->rd_maxcount -= entry_bytes;
3846 	/*
3847 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", and
3848 	 * notes that it could be zero. If it is zero, then the server
3849 	 * should enforce only the rd_maxcount value.
3850 	 */
3851 	if (cd->rd_dircount) {
3852 		name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8;
3853 		if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
3854 			goto fail;
3855 		cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
3856 		if (!cd->rd_dircount)
3857 			cd->rd_maxcount = 0;
3858 	}
3859 
3860 	cd->cookie_offset = cookie_offset;
3861 skip_entry:
3862 	cd->common.err = nfs_ok;
3863 	return 0;
3864 fail:
3865 	xdr_truncate_encode(xdr, start_offset);
3866 	cd->common.err = nfserr;
3867 	return -EINVAL;
3868 }
3869 
3870 static __be32
3871 nfsd4_encode_verifier4(struct xdr_stream *xdr, const nfs4_verifier *verf)
3872 {
3873 	__be32 *p;
3874 
3875 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3876 	if (!p)
3877 		return nfserr_resource;
3878 	memcpy(p, verf->data, sizeof(verf->data));
3879 	return nfs_ok;
3880 }
3881 
3882 static __be32
3883 nfsd4_encode_clientid4(struct xdr_stream *xdr, const clientid_t *clientid)
3884 {
3885 	__be32 *p;
3886 
3887 	p = xdr_reserve_space(xdr, sizeof(__be64));
3888 	if (!p)
3889 		return nfserr_resource;
3890 	memcpy(p, clientid, sizeof(*clientid));
3891 	return nfs_ok;
3892 }
3893 
3894 /* This is a frequently-encoded item; open-coded for speed */
3895 static __be32
3896 nfsd4_encode_stateid4(struct xdr_stream *xdr, const stateid_t *sid)
3897 {
3898 	__be32 *p;
3899 
3900 	p = xdr_reserve_space(xdr, NFS4_STATEID_SIZE);
3901 	if (!p)
3902 		return nfserr_resource;
3903 	*p++ = cpu_to_be32(sid->si_generation);
3904 	memcpy(p, &sid->si_opaque, sizeof(sid->si_opaque));
3905 	return nfs_ok;
3906 }
3907 
3908 static __be32
3909 nfsd4_encode_sessionid4(struct xdr_stream *xdr,
3910 			const struct nfs4_sessionid *sessionid)
3911 {
3912 	return nfsd4_encode_opaque_fixed(xdr, sessionid->data,
3913 					 NFS4_MAX_SESSIONID_LEN);
3914 }
3915 
3916 static __be32
3917 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr,
3918 		    union nfsd4_op_u *u)
3919 {
3920 	struct nfsd4_access *access = &u->access;
3921 	struct xdr_stream *xdr = resp->xdr;
3922 	__be32 status;
3923 
3924 	/* supported */
3925 	status = nfsd4_encode_uint32_t(xdr, access->ac_supported);
3926 	if (status != nfs_ok)
3927 		return status;
3928 	/* access */
3929 	return nfsd4_encode_uint32_t(xdr, access->ac_resp_access);
3930 }
3931 
3932 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr,
3933 						union nfsd4_op_u *u)
3934 {
3935 	struct nfsd4_bind_conn_to_session *bcts = &u->bind_conn_to_session;
3936 	struct xdr_stream *xdr = resp->xdr;
3937 
3938 	/* bctsr_sessid */
3939 	nfserr = nfsd4_encode_sessionid4(xdr, &bcts->sessionid);
3940 	if (nfserr != nfs_ok)
3941 		return nfserr;
3942 	/* bctsr_dir */
3943 	if (xdr_stream_encode_u32(xdr, bcts->dir) != XDR_UNIT)
3944 		return nfserr_resource;
3945 	/* bctsr_use_conn_in_rdma_mode */
3946 	return nfsd4_encode_bool(xdr, false);
3947 }
3948 
3949 static __be32
3950 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr,
3951 		   union nfsd4_op_u *u)
3952 {
3953 	struct nfsd4_close *close = &u->close;
3954 	struct xdr_stream *xdr = resp->xdr;
3955 
3956 	/* open_stateid */
3957 	return nfsd4_encode_stateid4(xdr, &close->cl_stateid);
3958 }
3959 
3960 
3961 static __be32
3962 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr,
3963 		    union nfsd4_op_u *u)
3964 {
3965 	struct nfsd4_commit *commit = &u->commit;
3966 
3967 	return nfsd4_encode_verifier4(resp->xdr, &commit->co_verf);
3968 }
3969 
3970 static __be32
3971 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr,
3972 		    union nfsd4_op_u *u)
3973 {
3974 	struct nfsd4_create *create = &u->create;
3975 	struct xdr_stream *xdr = resp->xdr;
3976 
3977 	/* cinfo */
3978 	nfserr = nfsd4_encode_change_info4(xdr, &create->cr_cinfo);
3979 	if (nfserr)
3980 		return nfserr;
3981 	/* attrset */
3982 	return nfsd4_encode_bitmap4(xdr, create->cr_bmval[0],
3983 				    create->cr_bmval[1], create->cr_bmval[2]);
3984 }
3985 
3986 static __be32
3987 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr,
3988 		     union nfsd4_op_u *u)
3989 {
3990 	struct nfsd4_getattr *getattr = &u->getattr;
3991 	struct svc_fh *fhp = getattr->ga_fhp;
3992 	struct xdr_stream *xdr = resp->xdr;
3993 
3994 	/* obj_attributes */
3995 	return nfsd4_encode_fattr4(resp->rqstp, xdr, fhp, fhp->fh_export,
3996 				   fhp->fh_dentry, getattr->ga_bmval, 0);
3997 }
3998 
3999 static __be32
4000 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr,
4001 		   union nfsd4_op_u *u)
4002 {
4003 	struct xdr_stream *xdr = resp->xdr;
4004 	struct svc_fh *fhp = u->getfh;
4005 
4006 	/* object */
4007 	return nfsd4_encode_nfs_fh4(xdr, &fhp->fh_handle);
4008 }
4009 
4010 static __be32
4011 nfsd4_encode_lock_owner4(struct xdr_stream *xdr, const clientid_t *clientid,
4012 			 const struct xdr_netobj *owner)
4013 {
4014 	__be32 status;
4015 
4016 	/* clientid */
4017 	status = nfsd4_encode_clientid4(xdr, clientid);
4018 	if (status != nfs_ok)
4019 		return status;
4020 	/* owner */
4021 	return nfsd4_encode_opaque(xdr, owner->data, owner->len);
4022 }
4023 
4024 static __be32
4025 nfsd4_encode_lock4denied(struct xdr_stream *xdr,
4026 			 const struct nfsd4_lock_denied *ld)
4027 {
4028 	__be32 status;
4029 
4030 	/* offset */
4031 	status = nfsd4_encode_offset4(xdr, ld->ld_start);
4032 	if (status != nfs_ok)
4033 		return status;
4034 	/* length */
4035 	status = nfsd4_encode_length4(xdr, ld->ld_length);
4036 	if (status != nfs_ok)
4037 		return status;
4038 	/* locktype */
4039 	if (xdr_stream_encode_u32(xdr, ld->ld_type) != XDR_UNIT)
4040 		return nfserr_resource;
4041 	/* owner */
4042 	return nfsd4_encode_lock_owner4(xdr, &ld->ld_clientid,
4043 					&ld->ld_owner);
4044 }
4045 
4046 static __be32
4047 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr,
4048 		  union nfsd4_op_u *u)
4049 {
4050 	struct nfsd4_lock *lock = &u->lock;
4051 	struct xdr_stream *xdr = resp->xdr;
4052 	__be32 status;
4053 
4054 	switch (nfserr) {
4055 	case nfs_ok:
4056 		/* resok4 */
4057 		status = nfsd4_encode_stateid4(xdr, &lock->lk_resp_stateid);
4058 		break;
4059 	case nfserr_denied:
4060 		/* denied */
4061 		status = nfsd4_encode_lock4denied(xdr, &lock->lk_denied);
4062 		break;
4063 	default:
4064 		return nfserr;
4065 	}
4066 	return status != nfs_ok ? status : nfserr;
4067 }
4068 
4069 static __be32
4070 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr,
4071 		   union nfsd4_op_u *u)
4072 {
4073 	struct nfsd4_lockt *lockt = &u->lockt;
4074 	struct xdr_stream *xdr = resp->xdr;
4075 	__be32 status;
4076 
4077 	if (nfserr == nfserr_denied) {
4078 		/* denied */
4079 		status = nfsd4_encode_lock4denied(xdr, &lockt->lt_denied);
4080 		if (status != nfs_ok)
4081 			return status;
4082 	}
4083 	return nfserr;
4084 }
4085 
4086 static __be32
4087 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr,
4088 		   union nfsd4_op_u *u)
4089 {
4090 	struct nfsd4_locku *locku = &u->locku;
4091 	struct xdr_stream *xdr = resp->xdr;
4092 
4093 	/* lock_stateid */
4094 	return nfsd4_encode_stateid4(xdr, &locku->lu_stateid);
4095 }
4096 
4097 
4098 static __be32
4099 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr,
4100 		  union nfsd4_op_u *u)
4101 {
4102 	struct nfsd4_link *link = &u->link;
4103 	struct xdr_stream *xdr = resp->xdr;
4104 
4105 	return nfsd4_encode_change_info4(xdr, &link->li_cinfo);
4106 }
4107 
4108 /*
4109  * This implementation does not yet support returning an ACE in an
4110  * OPEN that offers a delegation.
4111  */
4112 static __be32
4113 nfsd4_encode_open_nfsace4(struct xdr_stream *xdr)
4114 {
4115 	__be32 status;
4116 
4117 	/* type */
4118 	status = nfsd4_encode_acetype4(xdr, NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
4119 	if (status != nfs_ok)
4120 		return nfserr_resource;
4121 	/* flag */
4122 	status = nfsd4_encode_aceflag4(xdr, 0);
4123 	if (status != nfs_ok)
4124 		return nfserr_resource;
4125 	/* access mask */
4126 	status = nfsd4_encode_acemask4(xdr, 0);
4127 	if (status != nfs_ok)
4128 		return nfserr_resource;
4129 	/* who - empty for now */
4130 	if (xdr_stream_encode_u32(xdr, 0) != XDR_UNIT)
4131 		return nfserr_resource;
4132 	return nfs_ok;
4133 }
4134 
4135 static __be32
4136 nfsd4_encode_open_read_delegation4(struct xdr_stream *xdr, struct nfsd4_open *open)
4137 {
4138 	__be32 status;
4139 
4140 	/* stateid */
4141 	status = nfsd4_encode_stateid4(xdr, &open->op_delegate_stateid);
4142 	if (status != nfs_ok)
4143 		return status;
4144 	/* recall */
4145 	status = nfsd4_encode_bool(xdr, open->op_recall);
4146 	if (status != nfs_ok)
4147 		return status;
4148 	/* permissions */
4149 	return nfsd4_encode_open_nfsace4(xdr);
4150 }
4151 
4152 static __be32
4153 nfsd4_encode_nfs_space_limit4(struct xdr_stream *xdr, u64 filesize)
4154 {
4155 	/* limitby */
4156 	if (xdr_stream_encode_u32(xdr, NFS4_LIMIT_SIZE) != XDR_UNIT)
4157 		return nfserr_resource;
4158 	/* filesize */
4159 	return nfsd4_encode_uint64_t(xdr, filesize);
4160 }
4161 
4162 static __be32
4163 nfsd4_encode_open_write_delegation4(struct xdr_stream *xdr,
4164 				    struct nfsd4_open *open)
4165 {
4166 	__be32 status;
4167 
4168 	/* stateid */
4169 	status = nfsd4_encode_stateid4(xdr, &open->op_delegate_stateid);
4170 	if (status != nfs_ok)
4171 		return status;
4172 	/* recall */
4173 	status = nfsd4_encode_bool(xdr, open->op_recall);
4174 	if (status != nfs_ok)
4175 		return status;
4176 	/* space_limit */
4177 	status = nfsd4_encode_nfs_space_limit4(xdr, 0);
4178 	if (status != nfs_ok)
4179 		return status;
4180 	return nfsd4_encode_open_nfsace4(xdr);
4181 }
4182 
4183 static __be32
4184 nfsd4_encode_open_none_delegation4(struct xdr_stream *xdr,
4185 				   struct nfsd4_open *open)
4186 {
4187 	__be32 status = nfs_ok;
4188 
4189 	/* ond_why */
4190 	if (xdr_stream_encode_u32(xdr, open->op_why_no_deleg) != XDR_UNIT)
4191 		return nfserr_resource;
4192 	switch (open->op_why_no_deleg) {
4193 	case WND4_CONTENTION:
4194 		/* ond_server_will_push_deleg */
4195 		status = nfsd4_encode_bool(xdr, false);
4196 		break;
4197 	case WND4_RESOURCE:
4198 		/* ond_server_will_signal_avail */
4199 		status = nfsd4_encode_bool(xdr, false);
4200 	}
4201 	return status;
4202 }
4203 
4204 static __be32
4205 nfsd4_encode_open_delegation4(struct xdr_stream *xdr, struct nfsd4_open *open)
4206 {
4207 	__be32 status;
4208 
4209 	/* delegation_type */
4210 	if (xdr_stream_encode_u32(xdr, open->op_delegate_type) != XDR_UNIT)
4211 		return nfserr_resource;
4212 	switch (open->op_delegate_type) {
4213 	case NFS4_OPEN_DELEGATE_NONE:
4214 		status = nfs_ok;
4215 		break;
4216 	case NFS4_OPEN_DELEGATE_READ:
4217 		/* read */
4218 		status = nfsd4_encode_open_read_delegation4(xdr, open);
4219 		break;
4220 	case NFS4_OPEN_DELEGATE_WRITE:
4221 		/* write */
4222 		status = nfsd4_encode_open_write_delegation4(xdr, open);
4223 		break;
4224 	case NFS4_OPEN_DELEGATE_NONE_EXT:
4225 		/* od_whynone */
4226 		status = nfsd4_encode_open_none_delegation4(xdr, open);
4227 		break;
4228 	default:
4229 		status = nfserr_serverfault;
4230 	}
4231 
4232 	return status;
4233 }
4234 
4235 static __be32
4236 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr,
4237 		  union nfsd4_op_u *u)
4238 {
4239 	struct nfsd4_open *open = &u->open;
4240 	struct xdr_stream *xdr = resp->xdr;
4241 
4242 	/* stateid */
4243 	nfserr = nfsd4_encode_stateid4(xdr, &open->op_stateid);
4244 	if (nfserr != nfs_ok)
4245 		return nfserr;
4246 	/* cinfo */
4247 	nfserr = nfsd4_encode_change_info4(xdr, &open->op_cinfo);
4248 	if (nfserr != nfs_ok)
4249 		return nfserr;
4250 	/* rflags */
4251 	nfserr = nfsd4_encode_uint32_t(xdr, open->op_rflags);
4252 	if (nfserr != nfs_ok)
4253 		return nfserr;
4254 	/* attrset */
4255 	nfserr = nfsd4_encode_bitmap4(xdr, open->op_bmval[0],
4256 				      open->op_bmval[1], open->op_bmval[2]);
4257 	if (nfserr != nfs_ok)
4258 		return nfserr;
4259 	/* delegation */
4260 	return nfsd4_encode_open_delegation4(xdr, open);
4261 }
4262 
4263 static __be32
4264 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr,
4265 			  union nfsd4_op_u *u)
4266 {
4267 	struct nfsd4_open_confirm *oc = &u->open_confirm;
4268 	struct xdr_stream *xdr = resp->xdr;
4269 
4270 	/* open_stateid */
4271 	return nfsd4_encode_stateid4(xdr, &oc->oc_resp_stateid);
4272 }
4273 
4274 static __be32
4275 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr,
4276 			    union nfsd4_op_u *u)
4277 {
4278 	struct nfsd4_open_downgrade *od = &u->open_downgrade;
4279 	struct xdr_stream *xdr = resp->xdr;
4280 
4281 	/* open_stateid */
4282 	return nfsd4_encode_stateid4(xdr, &od->od_stateid);
4283 }
4284 
4285 /*
4286  * The operation of this function assumes that this is the only
4287  * READ operation in the COMPOUND. If there are multiple READs,
4288  * we use nfsd4_encode_readv().
4289  */
4290 static __be32 nfsd4_encode_splice_read(
4291 				struct nfsd4_compoundres *resp,
4292 				struct nfsd4_read *read,
4293 				struct file *file, unsigned long maxcount)
4294 {
4295 	struct xdr_stream *xdr = resp->xdr;
4296 	struct xdr_buf *buf = xdr->buf;
4297 	int status, space_left;
4298 	__be32 nfserr;
4299 
4300 	/*
4301 	 * Make sure there is room at the end of buf->head for
4302 	 * svcxdr_encode_opaque_pages() to create a tail buffer
4303 	 * to XDR-pad the payload.
4304 	 */
4305 	if (xdr->iov != xdr->buf->head || xdr->end - xdr->p < 1)
4306 		return nfserr_resource;
4307 
4308 	nfserr = nfsd_splice_read(read->rd_rqstp, read->rd_fhp,
4309 				  file, read->rd_offset, &maxcount,
4310 				  &read->rd_eof);
4311 	read->rd_length = maxcount;
4312 	if (nfserr)
4313 		goto out_err;
4314 	svcxdr_encode_opaque_pages(read->rd_rqstp, xdr, buf->pages,
4315 				   buf->page_base, maxcount);
4316 	status = svc_encode_result_payload(read->rd_rqstp,
4317 					   buf->head[0].iov_len, maxcount);
4318 	if (status) {
4319 		nfserr = nfserrno(status);
4320 		goto out_err;
4321 	}
4322 
4323 	/*
4324 	 * Prepare to encode subsequent operations.
4325 	 *
4326 	 * xdr_truncate_encode() is not safe to use after a successful
4327 	 * splice read has been done, so the following stream
4328 	 * manipulations are open-coded.
4329 	 */
4330 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
4331 				buf->buflen - buf->len);
4332 	buf->buflen = buf->len + space_left;
4333 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
4334 
4335 	return nfs_ok;
4336 
4337 out_err:
4338 	/*
4339 	 * nfsd_splice_actor may have already messed with the
4340 	 * page length; reset it so as not to confuse
4341 	 * xdr_truncate_encode in our caller.
4342 	 */
4343 	buf->page_len = 0;
4344 	return nfserr;
4345 }
4346 
4347 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
4348 				 struct nfsd4_read *read,
4349 				 struct file *file, unsigned long maxcount)
4350 {
4351 	struct xdr_stream *xdr = resp->xdr;
4352 	unsigned int base = xdr->buf->page_len & ~PAGE_MASK;
4353 	unsigned int starting_len = xdr->buf->len;
4354 	__be32 zero = xdr_zero;
4355 	__be32 nfserr;
4356 
4357 	if (xdr_reserve_space_vec(xdr, maxcount) < 0)
4358 		return nfserr_resource;
4359 
4360 	nfserr = nfsd_iter_read(resp->rqstp, read->rd_fhp, file,
4361 				read->rd_offset, &maxcount, base,
4362 				&read->rd_eof);
4363 	read->rd_length = maxcount;
4364 	if (nfserr)
4365 		return nfserr;
4366 	if (svc_encode_result_payload(resp->rqstp, starting_len, maxcount))
4367 		return nfserr_io;
4368 	xdr_truncate_encode(xdr, starting_len + xdr_align_size(maxcount));
4369 
4370 	write_bytes_to_xdr_buf(xdr->buf, starting_len + maxcount, &zero,
4371 			       xdr_pad_size(maxcount));
4372 	return nfs_ok;
4373 }
4374 
4375 static __be32
4376 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
4377 		  union nfsd4_op_u *u)
4378 {
4379 	struct nfsd4_compoundargs *argp = resp->rqstp->rq_argp;
4380 	struct nfsd4_read *read = &u->read;
4381 	struct xdr_stream *xdr = resp->xdr;
4382 	int starting_len = xdr->buf->len;
4383 	bool splice_ok = argp->splice_ok;
4384 	unsigned long maxcount;
4385 	struct file *file;
4386 	__be32 *p;
4387 
4388 	if (nfserr)
4389 		return nfserr;
4390 	file = read->rd_nf->nf_file;
4391 
4392 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
4393 	if (!p) {
4394 		WARN_ON_ONCE(splice_ok);
4395 		return nfserr_resource;
4396 	}
4397 	if (resp->xdr->buf->page_len && splice_ok) {
4398 		WARN_ON_ONCE(1);
4399 		return nfserr_serverfault;
4400 	}
4401 	xdr_commit_encode(xdr);
4402 
4403 	maxcount = min_t(unsigned long, read->rd_length,
4404 			 (xdr->buf->buflen - xdr->buf->len));
4405 
4406 	if (file->f_op->splice_read && splice_ok)
4407 		nfserr = nfsd4_encode_splice_read(resp, read, file, maxcount);
4408 	else
4409 		nfserr = nfsd4_encode_readv(resp, read, file, maxcount);
4410 	if (nfserr) {
4411 		xdr_truncate_encode(xdr, starting_len);
4412 		return nfserr;
4413 	}
4414 
4415 	p = xdr_encode_bool(p, read->rd_eof);
4416 	*p = cpu_to_be32(read->rd_length);
4417 	return nfs_ok;
4418 }
4419 
4420 static __be32
4421 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr,
4422 		      union nfsd4_op_u *u)
4423 {
4424 	struct nfsd4_readlink *readlink = &u->readlink;
4425 	__be32 *p, *maxcount_p, zero = xdr_zero;
4426 	struct xdr_stream *xdr = resp->xdr;
4427 	int length_offset = xdr->buf->len;
4428 	int maxcount, status;
4429 
4430 	maxcount_p = xdr_reserve_space(xdr, XDR_UNIT);
4431 	if (!maxcount_p)
4432 		return nfserr_resource;
4433 	maxcount = PAGE_SIZE;
4434 
4435 	p = xdr_reserve_space(xdr, maxcount);
4436 	if (!p)
4437 		return nfserr_resource;
4438 	/*
4439 	 * XXX: By default, vfs_readlink() will truncate symlinks if they
4440 	 * would overflow the buffer.  Is this kosher in NFSv4?  If not, one
4441 	 * easy fix is: if vfs_readlink() precisely fills the buffer, assume
4442 	 * that truncation occurred, and return NFS4ERR_RESOURCE.
4443 	 */
4444 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
4445 						(char *)p, &maxcount);
4446 	if (nfserr == nfserr_isdir)
4447 		nfserr = nfserr_inval;
4448 	if (nfserr)
4449 		goto out_err;
4450 	status = svc_encode_result_payload(readlink->rl_rqstp, length_offset,
4451 					   maxcount);
4452 	if (status) {
4453 		nfserr = nfserrno(status);
4454 		goto out_err;
4455 	}
4456 	*maxcount_p = cpu_to_be32(maxcount);
4457 	xdr_truncate_encode(xdr, length_offset + 4 + xdr_align_size(maxcount));
4458 	write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount, &zero,
4459 			       xdr_pad_size(maxcount));
4460 	return nfs_ok;
4461 
4462 out_err:
4463 	xdr_truncate_encode(xdr, length_offset);
4464 	return nfserr;
4465 }
4466 
4467 static __be32 nfsd4_encode_dirlist4(struct xdr_stream *xdr,
4468 				    struct nfsd4_readdir *readdir,
4469 				    u32 max_payload)
4470 {
4471 	int bytes_left, maxcount, starting_len = xdr->buf->len;
4472 	loff_t offset;
4473 	__be32 status;
4474 
4475 	/*
4476 	 * Number of bytes left for directory entries allowing for the
4477 	 * final 8 bytes of the readdir and a following failed op.
4478 	 */
4479 	bytes_left = xdr->buf->buflen - xdr->buf->len -
4480 		COMPOUND_ERR_SLACK_SPACE - XDR_UNIT * 2;
4481 	if (bytes_left < 0)
4482 		return nfserr_resource;
4483 	maxcount = min_t(u32, readdir->rd_maxcount, max_payload);
4484 
4485 	/*
4486 	 * The RFC defines rd_maxcount as the size of the
4487 	 * READDIR4resok structure, which includes the verifier
4488 	 * and the 8 bytes encoded at the end of this function.
4489 	 */
4490 	if (maxcount < XDR_UNIT * 4)
4491 		return nfserr_toosmall;
4492 	maxcount = min_t(int, maxcount - XDR_UNIT * 4, bytes_left);
4493 
4494 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0 */
4495 	if (!readdir->rd_dircount)
4496 		readdir->rd_dircount = max_payload;
4497 
4498 	/* *entries */
4499 	readdir->xdr = xdr;
4500 	readdir->rd_maxcount = maxcount;
4501 	readdir->common.err = 0;
4502 	readdir->cookie_offset = 0;
4503 	offset = readdir->rd_cookie;
4504 	status = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp, &offset,
4505 			      &readdir->common, nfsd4_encode_entry4);
4506 	if (status)
4507 		return status;
4508 	if (readdir->common.err == nfserr_toosmall &&
4509 	    xdr->buf->len == starting_len) {
4510 		/* No entries were encoded. Which limit did we hit? */
4511 		if (maxcount - XDR_UNIT * 4 < bytes_left)
4512 			/* It was the fault of rd_maxcount */
4513 			return nfserr_toosmall;
4514 		/* We ran out of buffer space */
4515 		return nfserr_resource;
4516 	}
4517 	/* Encode the final entry's cookie value */
4518 	nfsd4_encode_entry4_nfs_cookie4(readdir, offset);
4519 	/* No entries follow */
4520 	if (xdr_stream_encode_item_absent(xdr) != XDR_UNIT)
4521 		return nfserr_resource;
4522 
4523 	/* eof */
4524 	return nfsd4_encode_bool(xdr, readdir->common.err == nfserr_eof);
4525 }
4526 
4527 static __be32
4528 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr,
4529 		     union nfsd4_op_u *u)
4530 {
4531 	struct nfsd4_readdir *readdir = &u->readdir;
4532 	struct xdr_stream *xdr = resp->xdr;
4533 	int starting_len = xdr->buf->len;
4534 
4535 	/* cookieverf */
4536 	nfserr = nfsd4_encode_verifier4(xdr, &readdir->rd_verf);
4537 	if (nfserr != nfs_ok)
4538 		return nfserr;
4539 
4540 	/* reply */
4541 	nfserr = nfsd4_encode_dirlist4(xdr, readdir, svc_max_payload(resp->rqstp));
4542 	if (nfserr != nfs_ok)
4543 		xdr_truncate_encode(xdr, starting_len);
4544 	return nfserr;
4545 }
4546 
4547 static __be32
4548 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr,
4549 		    union nfsd4_op_u *u)
4550 {
4551 	struct nfsd4_remove *remove = &u->remove;
4552 	struct xdr_stream *xdr = resp->xdr;
4553 
4554 	return nfsd4_encode_change_info4(xdr, &remove->rm_cinfo);
4555 }
4556 
4557 static __be32
4558 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr,
4559 		    union nfsd4_op_u *u)
4560 {
4561 	struct nfsd4_rename *rename = &u->rename;
4562 	struct xdr_stream *xdr = resp->xdr;
4563 
4564 	nfserr = nfsd4_encode_change_info4(xdr, &rename->rn_sinfo);
4565 	if (nfserr)
4566 		return nfserr;
4567 	return nfsd4_encode_change_info4(xdr, &rename->rn_tinfo);
4568 }
4569 
4570 static __be32
4571 nfsd4_encode_rpcsec_gss_info(struct xdr_stream *xdr,
4572 			     struct rpcsec_gss_info *info)
4573 {
4574 	__be32 status;
4575 
4576 	/* oid */
4577 	if (xdr_stream_encode_opaque(xdr, info->oid.data, info->oid.len) < 0)
4578 		return nfserr_resource;
4579 	/* qop */
4580 	status = nfsd4_encode_qop4(xdr, info->qop);
4581 	if (status != nfs_ok)
4582 		return status;
4583 	/* service */
4584 	if (xdr_stream_encode_u32(xdr, info->service) != XDR_UNIT)
4585 		return nfserr_resource;
4586 
4587 	return nfs_ok;
4588 }
4589 
4590 static __be32
4591 nfsd4_do_encode_secinfo(struct xdr_stream *xdr, struct svc_export *exp)
4592 {
4593 	u32 i, nflavs, supported;
4594 	struct exp_flavor_info *flavs;
4595 	struct exp_flavor_info def_flavs[2];
4596 	static bool report = true;
4597 	__be32 *flavorsp;
4598 	__be32 status;
4599 
4600 	if (exp->ex_nflavors) {
4601 		flavs = exp->ex_flavors;
4602 		nflavs = exp->ex_nflavors;
4603 	} else { /* Handling of some defaults in absence of real secinfo: */
4604 		flavs = def_flavs;
4605 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
4606 			nflavs = 2;
4607 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
4608 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
4609 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
4610 			nflavs = 1;
4611 			flavs[0].pseudoflavor
4612 					= svcauth_gss_flavor(exp->ex_client);
4613 		} else {
4614 			nflavs = 1;
4615 			flavs[0].pseudoflavor
4616 					= exp->ex_client->flavour->flavour;
4617 		}
4618 	}
4619 
4620 	supported = 0;
4621 	flavorsp = xdr_reserve_space(xdr, XDR_UNIT);
4622 	if (!flavorsp)
4623 		return nfserr_resource;
4624 
4625 	for (i = 0; i < nflavs; i++) {
4626 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
4627 		struct rpcsec_gss_info info;
4628 
4629 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
4630 			supported++;
4631 
4632 			/* flavor */
4633 			status = nfsd4_encode_uint32_t(xdr, RPC_AUTH_GSS);
4634 			if (status != nfs_ok)
4635 				return status;
4636 			/* flavor_info */
4637 			status = nfsd4_encode_rpcsec_gss_info(xdr, &info);
4638 			if (status != nfs_ok)
4639 				return status;
4640 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
4641 			supported++;
4642 
4643 			/* flavor */
4644 			status = nfsd4_encode_uint32_t(xdr, pf);
4645 			if (status != nfs_ok)
4646 				return status;
4647 		} else {
4648 			if (report)
4649 				pr_warn("NFS: SECINFO: security flavor %u "
4650 					"is not supported\n", pf);
4651 		}
4652 	}
4653 
4654 	if (nflavs != supported)
4655 		report = false;
4656 	*flavorsp = cpu_to_be32(supported);
4657 	return 0;
4658 }
4659 
4660 static __be32
4661 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
4662 		     union nfsd4_op_u *u)
4663 {
4664 	struct nfsd4_secinfo *secinfo = &u->secinfo;
4665 	struct xdr_stream *xdr = resp->xdr;
4666 
4667 	return nfsd4_do_encode_secinfo(xdr, secinfo->si_exp);
4668 }
4669 
4670 static __be32
4671 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
4672 		     union nfsd4_op_u *u)
4673 {
4674 	struct nfsd4_secinfo_no_name *secinfo = &u->secinfo_no_name;
4675 	struct xdr_stream *xdr = resp->xdr;
4676 
4677 	return nfsd4_do_encode_secinfo(xdr, secinfo->sin_exp);
4678 }
4679 
4680 static __be32
4681 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr,
4682 		     union nfsd4_op_u *u)
4683 {
4684 	struct nfsd4_setattr *setattr = &u->setattr;
4685 	__be32 status;
4686 
4687 	switch (nfserr) {
4688 	case nfs_ok:
4689 		/* attrsset */
4690 		status = nfsd4_encode_bitmap4(resp->xdr, setattr->sa_bmval[0],
4691 					      setattr->sa_bmval[1],
4692 					      setattr->sa_bmval[2]);
4693 		break;
4694 	default:
4695 		/* attrsset */
4696 		status = nfsd4_encode_bitmap4(resp->xdr, 0, 0, 0);
4697 	}
4698 	return status != nfs_ok ? status : nfserr;
4699 }
4700 
4701 static __be32
4702 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr,
4703 			 union nfsd4_op_u *u)
4704 {
4705 	struct nfsd4_setclientid *scd = &u->setclientid;
4706 	struct xdr_stream *xdr = resp->xdr;
4707 
4708 	if (!nfserr) {
4709 		nfserr = nfsd4_encode_clientid4(xdr, &scd->se_clientid);
4710 		if (nfserr != nfs_ok)
4711 			goto out;
4712 		nfserr = nfsd4_encode_verifier4(xdr, &scd->se_confirm);
4713 	} else if (nfserr == nfserr_clid_inuse) {
4714 		/* empty network id */
4715 		if (xdr_stream_encode_u32(xdr, 0) < 0) {
4716 			nfserr = nfserr_resource;
4717 			goto out;
4718 		}
4719 		/* empty universal address */
4720 		if (xdr_stream_encode_u32(xdr, 0) < 0) {
4721 			nfserr = nfserr_resource;
4722 			goto out;
4723 		}
4724 	}
4725 out:
4726 	return nfserr;
4727 }
4728 
4729 static __be32
4730 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr,
4731 		   union nfsd4_op_u *u)
4732 {
4733 	struct nfsd4_write *write = &u->write;
4734 	struct xdr_stream *xdr = resp->xdr;
4735 
4736 	/* count */
4737 	nfserr = nfsd4_encode_count4(xdr, write->wr_bytes_written);
4738 	if (nfserr)
4739 		return nfserr;
4740 	/* committed */
4741 	if (xdr_stream_encode_u32(xdr, write->wr_how_written) != XDR_UNIT)
4742 		return nfserr_resource;
4743 	/* writeverf */
4744 	return nfsd4_encode_verifier4(xdr, &write->wr_verifier);
4745 }
4746 
4747 static __be32
4748 nfsd4_encode_state_protect_ops4(struct xdr_stream *xdr,
4749 				struct nfsd4_exchange_id *exid)
4750 {
4751 	__be32 status;
4752 
4753 	/* spo_must_enforce */
4754 	status = nfsd4_encode_bitmap4(xdr, exid->spo_must_enforce[0],
4755 				      exid->spo_must_enforce[1],
4756 				      exid->spo_must_enforce[2]);
4757 	if (status != nfs_ok)
4758 		return status;
4759 	/* spo_must_allow */
4760 	return nfsd4_encode_bitmap4(xdr, exid->spo_must_allow[0],
4761 				    exid->spo_must_allow[1],
4762 				    exid->spo_must_allow[2]);
4763 }
4764 
4765 static __be32
4766 nfsd4_encode_state_protect4_r(struct xdr_stream *xdr, struct nfsd4_exchange_id *exid)
4767 {
4768 	__be32 status;
4769 
4770 	if (xdr_stream_encode_u32(xdr, exid->spa_how) != XDR_UNIT)
4771 		return nfserr_resource;
4772 	switch (exid->spa_how) {
4773 	case SP4_NONE:
4774 		status = nfs_ok;
4775 		break;
4776 	case SP4_MACH_CRED:
4777 		/* spr_mach_ops */
4778 		status = nfsd4_encode_state_protect_ops4(xdr, exid);
4779 		break;
4780 	default:
4781 		status = nfserr_serverfault;
4782 	}
4783 	return status;
4784 }
4785 
4786 static __be32
4787 nfsd4_encode_server_owner4(struct xdr_stream *xdr, struct svc_rqst *rqstp)
4788 {
4789 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
4790 	__be32 status;
4791 
4792 	/* so_minor_id */
4793 	status = nfsd4_encode_uint64_t(xdr, 0);
4794 	if (status != nfs_ok)
4795 		return status;
4796 	/* so_major_id */
4797 	return nfsd4_encode_opaque(xdr, nn->nfsd_name, strlen(nn->nfsd_name));
4798 }
4799 
4800 static __be32
4801 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
4802 			 union nfsd4_op_u *u)
4803 {
4804 	struct nfsd_net *nn = net_generic(SVC_NET(resp->rqstp), nfsd_net_id);
4805 	struct nfsd4_exchange_id *exid = &u->exchange_id;
4806 	struct xdr_stream *xdr = resp->xdr;
4807 
4808 	/* eir_clientid */
4809 	nfserr = nfsd4_encode_clientid4(xdr, &exid->clientid);
4810 	if (nfserr != nfs_ok)
4811 		return nfserr;
4812 	/* eir_sequenceid */
4813 	nfserr = nfsd4_encode_sequenceid4(xdr, exid->seqid);
4814 	if (nfserr != nfs_ok)
4815 		return nfserr;
4816 	/* eir_flags */
4817 	nfserr = nfsd4_encode_uint32_t(xdr, exid->flags);
4818 	if (nfserr != nfs_ok)
4819 		return nfserr;
4820 	/* eir_state_protect */
4821 	nfserr = nfsd4_encode_state_protect4_r(xdr, exid);
4822 	if (nfserr != nfs_ok)
4823 		return nfserr;
4824 	/* eir_server_owner */
4825 	nfserr = nfsd4_encode_server_owner4(xdr, resp->rqstp);
4826 	if (nfserr != nfs_ok)
4827 		return nfserr;
4828 	/* eir_server_scope */
4829 	nfserr = nfsd4_encode_opaque(xdr, nn->nfsd_name,
4830 				     strlen(nn->nfsd_name));
4831 	if (nfserr != nfs_ok)
4832 		return nfserr;
4833 	/* eir_server_impl_id<1> */
4834 	if (xdr_stream_encode_u32(xdr, 0) != XDR_UNIT)
4835 		return nfserr_resource;
4836 
4837 	return nfs_ok;
4838 }
4839 
4840 static __be32
4841 nfsd4_encode_channel_attrs4(struct xdr_stream *xdr,
4842 			    const struct nfsd4_channel_attrs *attrs)
4843 {
4844 	__be32 status;
4845 
4846 	/* ca_headerpadsize */
4847 	status = nfsd4_encode_count4(xdr, 0);
4848 	if (status != nfs_ok)
4849 		return status;
4850 	/* ca_maxrequestsize */
4851 	status = nfsd4_encode_count4(xdr, attrs->maxreq_sz);
4852 	if (status != nfs_ok)
4853 		return status;
4854 	/* ca_maxresponsesize */
4855 	status = nfsd4_encode_count4(xdr, attrs->maxresp_sz);
4856 	if (status != nfs_ok)
4857 		return status;
4858 	/* ca_maxresponsesize_cached */
4859 	status = nfsd4_encode_count4(xdr, attrs->maxresp_cached);
4860 	if (status != nfs_ok)
4861 		return status;
4862 	/* ca_maxoperations */
4863 	status = nfsd4_encode_count4(xdr, attrs->maxops);
4864 	if (status != nfs_ok)
4865 		return status;
4866 	/* ca_maxrequests */
4867 	status = nfsd4_encode_count4(xdr, attrs->maxreqs);
4868 	if (status != nfs_ok)
4869 		return status;
4870 	/* ca_rdma_ird<1> */
4871 	if (xdr_stream_encode_u32(xdr, attrs->nr_rdma_attrs) != XDR_UNIT)
4872 		return nfserr_resource;
4873 	if (attrs->nr_rdma_attrs)
4874 		return nfsd4_encode_uint32_t(xdr, attrs->rdma_attrs);
4875 	return nfs_ok;
4876 }
4877 
4878 static __be32
4879 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
4880 			    union nfsd4_op_u *u)
4881 {
4882 	struct nfsd4_create_session *sess = &u->create_session;
4883 	struct xdr_stream *xdr = resp->xdr;
4884 
4885 	/* csr_sessionid */
4886 	nfserr = nfsd4_encode_sessionid4(xdr, &sess->sessionid);
4887 	if (nfserr != nfs_ok)
4888 		return nfserr;
4889 	/* csr_sequence */
4890 	nfserr = nfsd4_encode_sequenceid4(xdr, sess->seqid);
4891 	if (nfserr != nfs_ok)
4892 		return nfserr;
4893 	/* csr_flags */
4894 	nfserr = nfsd4_encode_uint32_t(xdr, sess->flags);
4895 	if (nfserr != nfs_ok)
4896 		return nfserr;
4897 	/* csr_fore_chan_attrs */
4898 	nfserr = nfsd4_encode_channel_attrs4(xdr, &sess->fore_channel);
4899 	if (nfserr != nfs_ok)
4900 		return nfserr;
4901 	/* csr_back_chan_attrs */
4902 	return nfsd4_encode_channel_attrs4(xdr, &sess->back_channel);
4903 }
4904 
4905 static __be32
4906 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
4907 		      union nfsd4_op_u *u)
4908 {
4909 	struct nfsd4_sequence *seq = &u->sequence;
4910 	struct xdr_stream *xdr = resp->xdr;
4911 
4912 	/* sr_sessionid */
4913 	nfserr = nfsd4_encode_sessionid4(xdr, &seq->sessionid);
4914 	if (nfserr != nfs_ok)
4915 		return nfserr;
4916 	/* sr_sequenceid */
4917 	nfserr = nfsd4_encode_sequenceid4(xdr, seq->seqid);
4918 	if (nfserr != nfs_ok)
4919 		return nfserr;
4920 	/* sr_slotid */
4921 	nfserr = nfsd4_encode_slotid4(xdr, seq->slotid);
4922 	if (nfserr != nfs_ok)
4923 		return nfserr;
4924 	/* Note slotid's are numbered from zero: */
4925 	/* sr_highest_slotid */
4926 	nfserr = nfsd4_encode_slotid4(xdr, seq->maxslots - 1);
4927 	if (nfserr != nfs_ok)
4928 		return nfserr;
4929 	/* sr_target_highest_slotid */
4930 	nfserr = nfsd4_encode_slotid4(xdr, seq->maxslots - 1);
4931 	if (nfserr != nfs_ok)
4932 		return nfserr;
4933 	/* sr_status_flags */
4934 	nfserr = nfsd4_encode_uint32_t(xdr, seq->status_flags);
4935 	if (nfserr != nfs_ok)
4936 		return nfserr;
4937 
4938 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
4939 	return nfs_ok;
4940 }
4941 
4942 static __be32
4943 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
4944 			  union nfsd4_op_u *u)
4945 {
4946 	struct nfsd4_test_stateid *test_stateid = &u->test_stateid;
4947 	struct nfsd4_test_stateid_id *stateid, *next;
4948 	struct xdr_stream *xdr = resp->xdr;
4949 
4950 	/* tsr_status_codes<> */
4951 	if (xdr_stream_encode_u32(xdr, test_stateid->ts_num_ids) != XDR_UNIT)
4952 		return nfserr_resource;
4953 	list_for_each_entry_safe(stateid, next,
4954 				 &test_stateid->ts_stateid_list, ts_id_list) {
4955 		if (xdr_stream_encode_be32(xdr, stateid->ts_id_status) != XDR_UNIT)
4956 			return nfserr_resource;
4957 	}
4958 	return nfs_ok;
4959 }
4960 
4961 #ifdef CONFIG_NFSD_PNFS
4962 static __be32
4963 nfsd4_encode_device_addr4(struct xdr_stream *xdr,
4964 			  const struct nfsd4_getdeviceinfo *gdev)
4965 {
4966 	u32 needed_len, starting_len = xdr->buf->len;
4967 	const struct nfsd4_layout_ops *ops;
4968 	__be32 status;
4969 
4970 	/* da_layout_type */
4971 	if (xdr_stream_encode_u32(xdr, gdev->gd_layout_type) != XDR_UNIT)
4972 		return nfserr_resource;
4973 	/* da_addr_body */
4974 	ops = nfsd4_layout_ops[gdev->gd_layout_type];
4975 	status = ops->encode_getdeviceinfo(xdr, gdev);
4976 	if (status != nfs_ok) {
4977 		/*
4978 		 * Don't burden the layout drivers with enforcing
4979 		 * gd_maxcount. Just tell the client to come back
4980 		 * with a bigger buffer if it's not enough.
4981 		 */
4982 		if (xdr->buf->len + XDR_UNIT > gdev->gd_maxcount)
4983 			goto toosmall;
4984 		return status;
4985 	}
4986 
4987 	return nfs_ok;
4988 
4989 toosmall:
4990 	needed_len = xdr->buf->len + XDR_UNIT;	/* notifications */
4991 	xdr_truncate_encode(xdr, starting_len);
4992 
4993 	status = nfsd4_encode_count4(xdr, needed_len);
4994 	if (status != nfs_ok)
4995 		return status;
4996 	return nfserr_toosmall;
4997 }
4998 
4999 static __be32
5000 nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
5001 		union nfsd4_op_u *u)
5002 {
5003 	struct nfsd4_getdeviceinfo *gdev = &u->getdeviceinfo;
5004 	struct xdr_stream *xdr = resp->xdr;
5005 
5006 	/* gdir_device_addr */
5007 	nfserr = nfsd4_encode_device_addr4(xdr, gdev);
5008 	if (nfserr)
5009 		return nfserr;
5010 	/* gdir_notification */
5011 	return nfsd4_encode_bitmap4(xdr, gdev->gd_notify_types, 0, 0);
5012 }
5013 
5014 static __be32
5015 nfsd4_encode_layout4(struct xdr_stream *xdr, const struct nfsd4_layoutget *lgp)
5016 {
5017 	const struct nfsd4_layout_ops *ops = nfsd4_layout_ops[lgp->lg_layout_type];
5018 	__be32 status;
5019 
5020 	/* lo_offset */
5021 	status = nfsd4_encode_offset4(xdr, lgp->lg_seg.offset);
5022 	if (status != nfs_ok)
5023 		return status;
5024 	/* lo_length */
5025 	status = nfsd4_encode_length4(xdr, lgp->lg_seg.length);
5026 	if (status != nfs_ok)
5027 		return status;
5028 	/* lo_iomode */
5029 	if (xdr_stream_encode_u32(xdr, lgp->lg_seg.iomode) != XDR_UNIT)
5030 		return nfserr_resource;
5031 	/* lo_content */
5032 	if (xdr_stream_encode_u32(xdr, lgp->lg_layout_type) != XDR_UNIT)
5033 		return nfserr_resource;
5034 	return ops->encode_layoutget(xdr, lgp);
5035 }
5036 
5037 static __be32
5038 nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr,
5039 		union nfsd4_op_u *u)
5040 {
5041 	struct nfsd4_layoutget *lgp = &u->layoutget;
5042 	struct xdr_stream *xdr = resp->xdr;
5043 
5044 	/* logr_return_on_close */
5045 	nfserr = nfsd4_encode_bool(xdr, true);
5046 	if (nfserr != nfs_ok)
5047 		return nfserr;
5048 	/* logr_stateid */
5049 	nfserr = nfsd4_encode_stateid4(xdr, &lgp->lg_sid);
5050 	if (nfserr != nfs_ok)
5051 		return nfserr;
5052 	/* logr_layout<> */
5053 	if (xdr_stream_encode_u32(xdr, 1) != XDR_UNIT)
5054 		return nfserr_resource;
5055 	return nfsd4_encode_layout4(xdr, lgp);
5056 }
5057 
5058 static __be32
5059 nfsd4_encode_layoutcommit(struct nfsd4_compoundres *resp, __be32 nfserr,
5060 			  union nfsd4_op_u *u)
5061 {
5062 	struct nfsd4_layoutcommit *lcp = &u->layoutcommit;
5063 	struct xdr_stream *xdr = resp->xdr;
5064 
5065 	/* ns_sizechanged */
5066 	nfserr = nfsd4_encode_bool(xdr, lcp->lc_size_chg);
5067 	if (nfserr != nfs_ok)
5068 		return nfserr;
5069 	if (lcp->lc_size_chg)
5070 		/* ns_size */
5071 		return nfsd4_encode_length4(xdr, lcp->lc_newsize);
5072 	return nfs_ok;
5073 }
5074 
5075 static __be32
5076 nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
5077 		union nfsd4_op_u *u)
5078 {
5079 	struct nfsd4_layoutreturn *lrp = &u->layoutreturn;
5080 	struct xdr_stream *xdr = resp->xdr;
5081 
5082 	/* lrs_present */
5083 	nfserr = nfsd4_encode_bool(xdr, lrp->lrs_present);
5084 	if (nfserr != nfs_ok)
5085 		return nfserr;
5086 	if (lrp->lrs_present)
5087 		/* lrs_stateid */
5088 		return nfsd4_encode_stateid4(xdr, &lrp->lr_sid);
5089 	return nfs_ok;
5090 }
5091 #endif /* CONFIG_NFSD_PNFS */
5092 
5093 static __be32
5094 nfsd4_encode_write_response4(struct xdr_stream *xdr,
5095 			     const struct nfsd4_copy *copy)
5096 {
5097 	const struct nfsd42_write_res *write = &copy->cp_res;
5098 	u32 count = nfsd4_copy_is_sync(copy) ? 0 : 1;
5099 	__be32 status;
5100 
5101 	/* wr_callback_id<1> */
5102 	if (xdr_stream_encode_u32(xdr, count) != XDR_UNIT)
5103 		return nfserr_resource;
5104 	if (count) {
5105 		status = nfsd4_encode_stateid4(xdr, &write->cb_stateid);
5106 		if (status != nfs_ok)
5107 			return status;
5108 	}
5109 
5110 	/* wr_count */
5111 	status = nfsd4_encode_length4(xdr, write->wr_bytes_written);
5112 	if (status != nfs_ok)
5113 		return status;
5114 	/* wr_committed */
5115 	if (xdr_stream_encode_u32(xdr, write->wr_stable_how) != XDR_UNIT)
5116 		return nfserr_resource;
5117 	/* wr_writeverf */
5118 	return nfsd4_encode_verifier4(xdr, &write->wr_verifier);
5119 }
5120 
5121 static __be32 nfsd4_encode_copy_requirements4(struct xdr_stream *xdr,
5122 					      const struct nfsd4_copy *copy)
5123 {
5124 	__be32 status;
5125 
5126 	/* cr_consecutive */
5127 	status = nfsd4_encode_bool(xdr, true);
5128 	if (status != nfs_ok)
5129 		return status;
5130 	/* cr_synchronous */
5131 	return nfsd4_encode_bool(xdr, nfsd4_copy_is_sync(copy));
5132 }
5133 
5134 static __be32
5135 nfsd4_encode_copy(struct nfsd4_compoundres *resp, __be32 nfserr,
5136 		  union nfsd4_op_u *u)
5137 {
5138 	struct nfsd4_copy *copy = &u->copy;
5139 
5140 	nfserr = nfsd4_encode_write_response4(resp->xdr, copy);
5141 	if (nfserr != nfs_ok)
5142 		return nfserr;
5143 	return nfsd4_encode_copy_requirements4(resp->xdr, copy);
5144 }
5145 
5146 static __be32
5147 nfsd4_encode_netloc4(struct xdr_stream *xdr, const struct nl4_server *ns)
5148 {
5149 	__be32 status;
5150 
5151 	if (xdr_stream_encode_u32(xdr, ns->nl4_type) != XDR_UNIT)
5152 		return nfserr_resource;
5153 	switch (ns->nl4_type) {
5154 	case NL4_NETADDR:
5155 		/* nl_addr */
5156 		status = nfsd4_encode_netaddr4(xdr, &ns->u.nl4_addr);
5157 		break;
5158 	default:
5159 		status = nfserr_serverfault;
5160 	}
5161 	return status;
5162 }
5163 
5164 static __be32
5165 nfsd4_encode_copy_notify(struct nfsd4_compoundres *resp, __be32 nfserr,
5166 			 union nfsd4_op_u *u)
5167 {
5168 	struct nfsd4_copy_notify *cn = &u->copy_notify;
5169 	struct xdr_stream *xdr = resp->xdr;
5170 
5171 	/* cnr_lease_time */
5172 	nfserr = nfsd4_encode_nfstime4(xdr, &cn->cpn_lease_time);
5173 	if (nfserr)
5174 		return nfserr;
5175 	/* cnr_stateid */
5176 	nfserr = nfsd4_encode_stateid4(xdr, &cn->cpn_cnr_stateid);
5177 	if (nfserr)
5178 		return nfserr;
5179 	/* cnr_source_server<> */
5180 	if (xdr_stream_encode_u32(xdr, 1) != XDR_UNIT)
5181 		return nfserr_resource;
5182 	return nfsd4_encode_netloc4(xdr, cn->cpn_src);
5183 }
5184 
5185 static __be32
5186 nfsd4_encode_offload_status(struct nfsd4_compoundres *resp, __be32 nfserr,
5187 			    union nfsd4_op_u *u)
5188 {
5189 	struct nfsd4_offload_status *os = &u->offload_status;
5190 	struct xdr_stream *xdr = resp->xdr;
5191 
5192 	/* osr_count */
5193 	nfserr = nfsd4_encode_length4(xdr, os->count);
5194 	if (nfserr != nfs_ok)
5195 		return nfserr;
5196 	/* osr_complete<1> */
5197 	if (xdr_stream_encode_u32(xdr, 0) != XDR_UNIT)
5198 		return nfserr_resource;
5199 	return nfs_ok;
5200 }
5201 
5202 static __be32
5203 nfsd4_encode_read_plus_data(struct nfsd4_compoundres *resp,
5204 			    struct nfsd4_read *read)
5205 {
5206 	struct nfsd4_compoundargs *argp = resp->rqstp->rq_argp;
5207 	struct file *file = read->rd_nf->nf_file;
5208 	struct xdr_stream *xdr = resp->xdr;
5209 	bool splice_ok = argp->splice_ok;
5210 	unsigned long maxcount;
5211 	__be32 nfserr, *p;
5212 
5213 	/* Content type, offset, byte count */
5214 	p = xdr_reserve_space(xdr, 4 + 8 + 4);
5215 	if (!p)
5216 		return nfserr_io;
5217 	if (resp->xdr->buf->page_len && splice_ok) {
5218 		WARN_ON_ONCE(splice_ok);
5219 		return nfserr_serverfault;
5220 	}
5221 
5222 	maxcount = min_t(unsigned long, read->rd_length,
5223 			 (xdr->buf->buflen - xdr->buf->len));
5224 
5225 	if (file->f_op->splice_read && splice_ok)
5226 		nfserr = nfsd4_encode_splice_read(resp, read, file, maxcount);
5227 	else
5228 		nfserr = nfsd4_encode_readv(resp, read, file, maxcount);
5229 	if (nfserr)
5230 		return nfserr;
5231 
5232 	*p++ = cpu_to_be32(NFS4_CONTENT_DATA);
5233 	p = xdr_encode_hyper(p, read->rd_offset);
5234 	*p = cpu_to_be32(read->rd_length);
5235 
5236 	return nfs_ok;
5237 }
5238 
5239 static __be32
5240 nfsd4_encode_read_plus(struct nfsd4_compoundres *resp, __be32 nfserr,
5241 		       union nfsd4_op_u *u)
5242 {
5243 	struct nfsd4_read *read = &u->read;
5244 	struct file *file = read->rd_nf->nf_file;
5245 	struct xdr_stream *xdr = resp->xdr;
5246 	int starting_len = xdr->buf->len;
5247 	u32 segments = 0;
5248 	__be32 *p;
5249 
5250 	if (nfserr)
5251 		return nfserr;
5252 
5253 	/* eof flag, segment count */
5254 	p = xdr_reserve_space(xdr, 4 + 4);
5255 	if (!p)
5256 		return nfserr_io;
5257 	xdr_commit_encode(xdr);
5258 
5259 	read->rd_eof = read->rd_offset >= i_size_read(file_inode(file));
5260 	if (read->rd_eof)
5261 		goto out;
5262 
5263 	nfserr = nfsd4_encode_read_plus_data(resp, read);
5264 	if (nfserr) {
5265 		xdr_truncate_encode(xdr, starting_len);
5266 		return nfserr;
5267 	}
5268 
5269 	segments++;
5270 
5271 out:
5272 	p = xdr_encode_bool(p, read->rd_eof);
5273 	*p = cpu_to_be32(segments);
5274 	return nfserr;
5275 }
5276 
5277 static __be32
5278 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
5279 		  union nfsd4_op_u *u)
5280 {
5281 	struct nfsd4_seek *seek = &u->seek;
5282 	struct xdr_stream *xdr = resp->xdr;
5283 
5284 	/* sr_eof */
5285 	nfserr = nfsd4_encode_bool(xdr, seek->seek_eof);
5286 	if (nfserr != nfs_ok)
5287 		return nfserr;
5288 	/* sr_offset */
5289 	return nfsd4_encode_offset4(xdr, seek->seek_pos);
5290 }
5291 
5292 static __be32
5293 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr,
5294 		  union nfsd4_op_u *p)
5295 {
5296 	return nfserr;
5297 }
5298 
5299 /*
5300  * Encode kmalloc-ed buffer in to XDR stream.
5301  */
5302 static __be32
5303 nfsd4_vbuf_to_stream(struct xdr_stream *xdr, char *buf, u32 buflen)
5304 {
5305 	u32 cplen;
5306 	__be32 *p;
5307 
5308 	cplen = min_t(unsigned long, buflen,
5309 		      ((void *)xdr->end - (void *)xdr->p));
5310 	p = xdr_reserve_space(xdr, cplen);
5311 	if (!p)
5312 		return nfserr_resource;
5313 
5314 	memcpy(p, buf, cplen);
5315 	buf += cplen;
5316 	buflen -= cplen;
5317 
5318 	while (buflen) {
5319 		cplen = min_t(u32, buflen, PAGE_SIZE);
5320 		p = xdr_reserve_space(xdr, cplen);
5321 		if (!p)
5322 			return nfserr_resource;
5323 
5324 		memcpy(p, buf, cplen);
5325 
5326 		if (cplen < PAGE_SIZE) {
5327 			/*
5328 			 * We're done, with a length that wasn't page
5329 			 * aligned, so possibly not word aligned. Pad
5330 			 * any trailing bytes with 0.
5331 			 */
5332 			xdr_encode_opaque_fixed(p, NULL, cplen);
5333 			break;
5334 		}
5335 
5336 		buflen -= PAGE_SIZE;
5337 		buf += PAGE_SIZE;
5338 	}
5339 
5340 	return 0;
5341 }
5342 
5343 static __be32
5344 nfsd4_encode_getxattr(struct nfsd4_compoundres *resp, __be32 nfserr,
5345 		      union nfsd4_op_u *u)
5346 {
5347 	struct nfsd4_getxattr *getxattr = &u->getxattr;
5348 	struct xdr_stream *xdr = resp->xdr;
5349 	__be32 *p, err;
5350 
5351 	p = xdr_reserve_space(xdr, 4);
5352 	if (!p)
5353 		return nfserr_resource;
5354 
5355 	*p = cpu_to_be32(getxattr->getxa_len);
5356 
5357 	if (getxattr->getxa_len == 0)
5358 		return 0;
5359 
5360 	err = nfsd4_vbuf_to_stream(xdr, getxattr->getxa_buf,
5361 				    getxattr->getxa_len);
5362 
5363 	kvfree(getxattr->getxa_buf);
5364 
5365 	return err;
5366 }
5367 
5368 static __be32
5369 nfsd4_encode_setxattr(struct nfsd4_compoundres *resp, __be32 nfserr,
5370 		      union nfsd4_op_u *u)
5371 {
5372 	struct nfsd4_setxattr *setxattr = &u->setxattr;
5373 	struct xdr_stream *xdr = resp->xdr;
5374 
5375 	return nfsd4_encode_change_info4(xdr, &setxattr->setxa_cinfo);
5376 }
5377 
5378 /*
5379  * See if there are cookie values that can be rejected outright.
5380  */
5381 static __be32
5382 nfsd4_listxattr_validate_cookie(struct nfsd4_listxattrs *listxattrs,
5383 				u32 *offsetp)
5384 {
5385 	u64 cookie = listxattrs->lsxa_cookie;
5386 
5387 	/*
5388 	 * If the cookie is larger than the maximum number we can fit
5389 	 * in either the buffer we just got back from vfs_listxattr, or,
5390 	 * XDR-encoded, in the return buffer, it's invalid.
5391 	 */
5392 	if (cookie > (listxattrs->lsxa_len) / (XATTR_USER_PREFIX_LEN + 2))
5393 		return nfserr_badcookie;
5394 
5395 	if (cookie > (listxattrs->lsxa_maxcount /
5396 		      (XDR_QUADLEN(XATTR_USER_PREFIX_LEN + 2) + 4)))
5397 		return nfserr_badcookie;
5398 
5399 	*offsetp = (u32)cookie;
5400 	return 0;
5401 }
5402 
5403 static __be32
5404 nfsd4_encode_listxattrs(struct nfsd4_compoundres *resp, __be32 nfserr,
5405 			union nfsd4_op_u *u)
5406 {
5407 	struct nfsd4_listxattrs *listxattrs = &u->listxattrs;
5408 	struct xdr_stream *xdr = resp->xdr;
5409 	u32 cookie_offset, count_offset, eof;
5410 	u32 left, xdrleft, slen, count;
5411 	u32 xdrlen, offset;
5412 	u64 cookie;
5413 	char *sp;
5414 	__be32 status, tmp;
5415 	__be32 *p;
5416 	u32 nuser;
5417 
5418 	eof = 1;
5419 
5420 	status = nfsd4_listxattr_validate_cookie(listxattrs, &offset);
5421 	if (status)
5422 		goto out;
5423 
5424 	/*
5425 	 * Reserve space for the cookie and the name array count. Record
5426 	 * the offsets to save them later.
5427 	 */
5428 	cookie_offset = xdr->buf->len;
5429 	count_offset = cookie_offset + 8;
5430 	p = xdr_reserve_space(xdr, 12);
5431 	if (!p) {
5432 		status = nfserr_resource;
5433 		goto out;
5434 	}
5435 
5436 	count = 0;
5437 	left = listxattrs->lsxa_len;
5438 	sp = listxattrs->lsxa_buf;
5439 	nuser = 0;
5440 
5441 	xdrleft = listxattrs->lsxa_maxcount;
5442 
5443 	while (left > 0 && xdrleft > 0) {
5444 		slen = strlen(sp);
5445 
5446 		/*
5447 		 * Check if this is a "user." attribute, skip it if not.
5448 		 */
5449 		if (strncmp(sp, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN))
5450 			goto contloop;
5451 
5452 		slen -= XATTR_USER_PREFIX_LEN;
5453 		xdrlen = 4 + ((slen + 3) & ~3);
5454 		if (xdrlen > xdrleft) {
5455 			if (count == 0) {
5456 				/*
5457 				 * Can't even fit the first attribute name.
5458 				 */
5459 				status = nfserr_toosmall;
5460 				goto out;
5461 			}
5462 			eof = 0;
5463 			goto wreof;
5464 		}
5465 
5466 		left -= XATTR_USER_PREFIX_LEN;
5467 		sp += XATTR_USER_PREFIX_LEN;
5468 		if (nuser++ < offset)
5469 			goto contloop;
5470 
5471 
5472 		p = xdr_reserve_space(xdr, xdrlen);
5473 		if (!p) {
5474 			status = nfserr_resource;
5475 			goto out;
5476 		}
5477 
5478 		xdr_encode_opaque(p, sp, slen);
5479 
5480 		xdrleft -= xdrlen;
5481 		count++;
5482 contloop:
5483 		sp += slen + 1;
5484 		left -= slen + 1;
5485 	}
5486 
5487 	/*
5488 	 * If there were user attributes to copy, but we didn't copy
5489 	 * any, the offset was too large (e.g. the cookie was invalid).
5490 	 */
5491 	if (nuser > 0 && count == 0) {
5492 		status = nfserr_badcookie;
5493 		goto out;
5494 	}
5495 
5496 wreof:
5497 	p = xdr_reserve_space(xdr, 4);
5498 	if (!p) {
5499 		status = nfserr_resource;
5500 		goto out;
5501 	}
5502 	*p = cpu_to_be32(eof);
5503 
5504 	cookie = offset + count;
5505 
5506 	write_bytes_to_xdr_buf(xdr->buf, cookie_offset, &cookie, 8);
5507 	tmp = cpu_to_be32(count);
5508 	write_bytes_to_xdr_buf(xdr->buf, count_offset, &tmp, 4);
5509 out:
5510 	if (listxattrs->lsxa_len)
5511 		kvfree(listxattrs->lsxa_buf);
5512 	return status;
5513 }
5514 
5515 static __be32
5516 nfsd4_encode_removexattr(struct nfsd4_compoundres *resp, __be32 nfserr,
5517 			 union nfsd4_op_u *u)
5518 {
5519 	struct nfsd4_removexattr *removexattr = &u->removexattr;
5520 	struct xdr_stream *xdr = resp->xdr;
5521 
5522 	return nfsd4_encode_change_info4(xdr, &removexattr->rmxa_cinfo);
5523 }
5524 
5525 typedef __be32(*nfsd4_enc)(struct nfsd4_compoundres *, __be32, union nfsd4_op_u *u);
5526 
5527 /*
5528  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
5529  * since we don't need to filter out obsolete ops as this is
5530  * done in the decoding phase.
5531  */
5532 static const nfsd4_enc nfsd4_enc_ops[] = {
5533 	[OP_ACCESS]		= nfsd4_encode_access,
5534 	[OP_CLOSE]		= nfsd4_encode_close,
5535 	[OP_COMMIT]		= nfsd4_encode_commit,
5536 	[OP_CREATE]		= nfsd4_encode_create,
5537 	[OP_DELEGPURGE]		= nfsd4_encode_noop,
5538 	[OP_DELEGRETURN]	= nfsd4_encode_noop,
5539 	[OP_GETATTR]		= nfsd4_encode_getattr,
5540 	[OP_GETFH]		= nfsd4_encode_getfh,
5541 	[OP_LINK]		= nfsd4_encode_link,
5542 	[OP_LOCK]		= nfsd4_encode_lock,
5543 	[OP_LOCKT]		= nfsd4_encode_lockt,
5544 	[OP_LOCKU]		= nfsd4_encode_locku,
5545 	[OP_LOOKUP]		= nfsd4_encode_noop,
5546 	[OP_LOOKUPP]		= nfsd4_encode_noop,
5547 	[OP_NVERIFY]		= nfsd4_encode_noop,
5548 	[OP_OPEN]		= nfsd4_encode_open,
5549 	[OP_OPENATTR]		= nfsd4_encode_noop,
5550 	[OP_OPEN_CONFIRM]	= nfsd4_encode_open_confirm,
5551 	[OP_OPEN_DOWNGRADE]	= nfsd4_encode_open_downgrade,
5552 	[OP_PUTFH]		= nfsd4_encode_noop,
5553 	[OP_PUTPUBFH]		= nfsd4_encode_noop,
5554 	[OP_PUTROOTFH]		= nfsd4_encode_noop,
5555 	[OP_READ]		= nfsd4_encode_read,
5556 	[OP_READDIR]		= nfsd4_encode_readdir,
5557 	[OP_READLINK]		= nfsd4_encode_readlink,
5558 	[OP_REMOVE]		= nfsd4_encode_remove,
5559 	[OP_RENAME]		= nfsd4_encode_rename,
5560 	[OP_RENEW]		= nfsd4_encode_noop,
5561 	[OP_RESTOREFH]		= nfsd4_encode_noop,
5562 	[OP_SAVEFH]		= nfsd4_encode_noop,
5563 	[OP_SECINFO]		= nfsd4_encode_secinfo,
5564 	[OP_SETATTR]		= nfsd4_encode_setattr,
5565 	[OP_SETCLIENTID]	= nfsd4_encode_setclientid,
5566 	[OP_SETCLIENTID_CONFIRM] = nfsd4_encode_noop,
5567 	[OP_VERIFY]		= nfsd4_encode_noop,
5568 	[OP_WRITE]		= nfsd4_encode_write,
5569 	[OP_RELEASE_LOCKOWNER]	= nfsd4_encode_noop,
5570 
5571 	/* NFSv4.1 operations */
5572 	[OP_BACKCHANNEL_CTL]	= nfsd4_encode_noop,
5573 	[OP_BIND_CONN_TO_SESSION] = nfsd4_encode_bind_conn_to_session,
5574 	[OP_EXCHANGE_ID]	= nfsd4_encode_exchange_id,
5575 	[OP_CREATE_SESSION]	= nfsd4_encode_create_session,
5576 	[OP_DESTROY_SESSION]	= nfsd4_encode_noop,
5577 	[OP_FREE_STATEID]	= nfsd4_encode_noop,
5578 	[OP_GET_DIR_DELEGATION]	= nfsd4_encode_noop,
5579 #ifdef CONFIG_NFSD_PNFS
5580 	[OP_GETDEVICEINFO]	= nfsd4_encode_getdeviceinfo,
5581 	[OP_GETDEVICELIST]	= nfsd4_encode_noop,
5582 	[OP_LAYOUTCOMMIT]	= nfsd4_encode_layoutcommit,
5583 	[OP_LAYOUTGET]		= nfsd4_encode_layoutget,
5584 	[OP_LAYOUTRETURN]	= nfsd4_encode_layoutreturn,
5585 #else
5586 	[OP_GETDEVICEINFO]	= nfsd4_encode_noop,
5587 	[OP_GETDEVICELIST]	= nfsd4_encode_noop,
5588 	[OP_LAYOUTCOMMIT]	= nfsd4_encode_noop,
5589 	[OP_LAYOUTGET]		= nfsd4_encode_noop,
5590 	[OP_LAYOUTRETURN]	= nfsd4_encode_noop,
5591 #endif
5592 	[OP_SECINFO_NO_NAME]	= nfsd4_encode_secinfo_no_name,
5593 	[OP_SEQUENCE]		= nfsd4_encode_sequence,
5594 	[OP_SET_SSV]		= nfsd4_encode_noop,
5595 	[OP_TEST_STATEID]	= nfsd4_encode_test_stateid,
5596 	[OP_WANT_DELEGATION]	= nfsd4_encode_noop,
5597 	[OP_DESTROY_CLIENTID]	= nfsd4_encode_noop,
5598 	[OP_RECLAIM_COMPLETE]	= nfsd4_encode_noop,
5599 
5600 	/* NFSv4.2 operations */
5601 	[OP_ALLOCATE]		= nfsd4_encode_noop,
5602 	[OP_COPY]		= nfsd4_encode_copy,
5603 	[OP_COPY_NOTIFY]	= nfsd4_encode_copy_notify,
5604 	[OP_DEALLOCATE]		= nfsd4_encode_noop,
5605 	[OP_IO_ADVISE]		= nfsd4_encode_noop,
5606 	[OP_LAYOUTERROR]	= nfsd4_encode_noop,
5607 	[OP_LAYOUTSTATS]	= nfsd4_encode_noop,
5608 	[OP_OFFLOAD_CANCEL]	= nfsd4_encode_noop,
5609 	[OP_OFFLOAD_STATUS]	= nfsd4_encode_offload_status,
5610 	[OP_READ_PLUS]		= nfsd4_encode_read_plus,
5611 	[OP_SEEK]		= nfsd4_encode_seek,
5612 	[OP_WRITE_SAME]		= nfsd4_encode_noop,
5613 	[OP_CLONE]		= nfsd4_encode_noop,
5614 
5615 	/* RFC 8276 extended atributes operations */
5616 	[OP_GETXATTR]		= nfsd4_encode_getxattr,
5617 	[OP_SETXATTR]		= nfsd4_encode_setxattr,
5618 	[OP_LISTXATTRS]		= nfsd4_encode_listxattrs,
5619 	[OP_REMOVEXATTR]	= nfsd4_encode_removexattr,
5620 };
5621 
5622 /*
5623  * Calculate whether we still have space to encode repsize bytes.
5624  * There are two considerations:
5625  *     - For NFS versions >=4.1, the size of the reply must stay within
5626  *       session limits
5627  *     - For all NFS versions, we must stay within limited preallocated
5628  *       buffer space.
5629  *
5630  * This is called before the operation is processed, so can only provide
5631  * an upper estimate.  For some nonidempotent operations (such as
5632  * getattr), it's not necessarily a problem if that estimate is wrong,
5633  * as we can fail it after processing without significant side effects.
5634  */
5635 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
5636 {
5637 	struct xdr_buf *buf = &resp->rqstp->rq_res;
5638 	struct nfsd4_slot *slot = resp->cstate.slot;
5639 
5640 	if (buf->len + respsize <= buf->buflen)
5641 		return nfs_ok;
5642 	if (!nfsd4_has_session(&resp->cstate))
5643 		return nfserr_resource;
5644 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
5645 		WARN_ON_ONCE(1);
5646 		return nfserr_rep_too_big_to_cache;
5647 	}
5648 	return nfserr_rep_too_big;
5649 }
5650 
5651 void
5652 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
5653 {
5654 	struct xdr_stream *xdr = resp->xdr;
5655 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
5656 	struct svc_rqst *rqstp = resp->rqstp;
5657 	const struct nfsd4_operation *opdesc = op->opdesc;
5658 	int post_err_offset;
5659 	nfsd4_enc encoder;
5660 	__be32 *p;
5661 
5662 	p = xdr_reserve_space(xdr, 8);
5663 	if (!p)
5664 		goto release;
5665 	*p++ = cpu_to_be32(op->opnum);
5666 	post_err_offset = xdr->buf->len;
5667 
5668 	if (op->opnum == OP_ILLEGAL)
5669 		goto status;
5670 	if (op->status && opdesc &&
5671 			!(opdesc->op_flags & OP_NONTRIVIAL_ERROR_ENCODE))
5672 		goto status;
5673 	BUG_ON(op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
5674 	       !nfsd4_enc_ops[op->opnum]);
5675 	encoder = nfsd4_enc_ops[op->opnum];
5676 	op->status = encoder(resp, op->status, &op->u);
5677 	if (op->status)
5678 		trace_nfsd_compound_encode_err(rqstp, op->opnum, op->status);
5679 	xdr_commit_encode(xdr);
5680 
5681 	/* nfsd4_check_resp_size guarantees enough room for error status */
5682 	if (!op->status) {
5683 		int space_needed = 0;
5684 		if (!nfsd4_last_compound_op(rqstp))
5685 			space_needed = COMPOUND_ERR_SLACK_SPACE;
5686 		op->status = nfsd4_check_resp_size(resp, space_needed);
5687 	}
5688 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
5689 		struct nfsd4_slot *slot = resp->cstate.slot;
5690 
5691 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
5692 			op->status = nfserr_rep_too_big_to_cache;
5693 		else
5694 			op->status = nfserr_rep_too_big;
5695 	}
5696 	if (op->status == nfserr_resource ||
5697 	    op->status == nfserr_rep_too_big ||
5698 	    op->status == nfserr_rep_too_big_to_cache) {
5699 		/*
5700 		 * The operation may have already been encoded or
5701 		 * partially encoded.  No op returns anything additional
5702 		 * in the case of one of these three errors, so we can
5703 		 * just truncate back to after the status.  But it's a
5704 		 * bug if we had to do this on a non-idempotent op:
5705 		 */
5706 		warn_on_nonidempotent_op(op);
5707 		xdr_truncate_encode(xdr, post_err_offset);
5708 	}
5709 	if (so) {
5710 		int len = xdr->buf->len - post_err_offset;
5711 
5712 		so->so_replay.rp_status = op->status;
5713 		so->so_replay.rp_buflen = len;
5714 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
5715 						so->so_replay.rp_buf, len);
5716 	}
5717 status:
5718 	*p = op->status;
5719 release:
5720 	if (opdesc && opdesc->op_release)
5721 		opdesc->op_release(&op->u);
5722 
5723 	/*
5724 	 * Account for pages consumed while encoding this operation.
5725 	 * The xdr_stream primitives don't manage rq_next_page.
5726 	 */
5727 	rqstp->rq_next_page = xdr->page_ptr + 1;
5728 }
5729 
5730 /*
5731  * Encode the reply stored in the stateowner reply cache
5732  *
5733  * XDR note: do not encode rp->rp_buflen: the buffer contains the
5734  * previously sent already encoded operation.
5735  */
5736 void
5737 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
5738 {
5739 	__be32 *p;
5740 	struct nfs4_replay *rp = op->replay;
5741 
5742 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
5743 	if (!p) {
5744 		WARN_ON_ONCE(1);
5745 		return;
5746 	}
5747 	*p++ = cpu_to_be32(op->opnum);
5748 	*p++ = rp->rp_status;  /* already xdr'ed */
5749 
5750 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
5751 }
5752 
5753 void nfsd4_release_compoundargs(struct svc_rqst *rqstp)
5754 {
5755 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
5756 
5757 	if (args->ops != args->iops) {
5758 		vfree(args->ops);
5759 		args->ops = args->iops;
5760 	}
5761 	while (args->to_free) {
5762 		struct svcxdr_tmpbuf *tb = args->to_free;
5763 		args->to_free = tb->next;
5764 		kfree(tb);
5765 	}
5766 }
5767 
5768 bool
5769 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, struct xdr_stream *xdr)
5770 {
5771 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
5772 
5773 	/* svcxdr_tmp_alloc */
5774 	args->to_free = NULL;
5775 
5776 	args->xdr = xdr;
5777 	args->ops = args->iops;
5778 	args->rqstp = rqstp;
5779 
5780 	return nfsd4_decode_compound(args);
5781 }
5782 
5783 bool
5784 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, struct xdr_stream *xdr)
5785 {
5786 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
5787 	__be32 *p;
5788 
5789 	/*
5790 	 * Send buffer space for the following items is reserved
5791 	 * at the top of nfsd4_proc_compound().
5792 	 */
5793 	p = resp->statusp;
5794 
5795 	*p++ = resp->cstate.status;
5796 	*p++ = htonl(resp->taglen);
5797 	memcpy(p, resp->tag, resp->taglen);
5798 	p += XDR_QUADLEN(resp->taglen);
5799 	*p++ = htonl(resp->opcnt);
5800 
5801 	nfsd4_sequence_done(resp);
5802 	return true;
5803 }
5804