xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision b8d312aa)
1 /*
2  *  Server-side XDR for NFSv4
3  *
4  *  Copyright (c) 2002 The Regents of the University of Michigan.
5  *  All rights reserved.
6  *
7  *  Kendrick Smith <kmsmith@umich.edu>
8  *  Andy Adamson   <andros@umich.edu>
9  *
10  *  Redistribution and use in source and binary forms, with or without
11  *  modification, are permitted provided that the following conditions
12  *  are met:
13  *
14  *  1. Redistributions of source code must retain the above copyright
15  *     notice, this list of conditions and the following disclaimer.
16  *  2. Redistributions in binary form must reproduce the above copyright
17  *     notice, this list of conditions and the following disclaimer in the
18  *     documentation and/or other materials provided with the distribution.
19  *  3. Neither the name of the University nor the names of its
20  *     contributors may be used to endorse or promote products derived
21  *     from this software without specific prior written permission.
22  *
23  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
24  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
30  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 #include <linux/file.h>
37 #include <linux/slab.h>
38 #include <linux/namei.h>
39 #include <linux/statfs.h>
40 #include <linux/utsname.h>
41 #include <linux/pagemap.h>
42 #include <linux/sunrpc/svcauth_gss.h>
43 
44 #include "idmap.h"
45 #include "acl.h"
46 #include "xdr4.h"
47 #include "vfs.h"
48 #include "state.h"
49 #include "cache.h"
50 #include "netns.h"
51 #include "pnfs.h"
52 
53 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
54 #include <linux/security.h>
55 #endif
56 
57 
58 #define NFSDDBG_FACILITY		NFSDDBG_XDR
59 
60 const u32 nfsd_suppattrs[3][3] = {
61 	{NFSD4_SUPPORTED_ATTRS_WORD0,
62 	 NFSD4_SUPPORTED_ATTRS_WORD1,
63 	 NFSD4_SUPPORTED_ATTRS_WORD2},
64 
65 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
66 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
67 	 NFSD4_1_SUPPORTED_ATTRS_WORD2},
68 
69 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
70 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
71 	 NFSD4_2_SUPPORTED_ATTRS_WORD2},
72 };
73 
74 /*
75  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
76  * directory in order to indicate to the client that a filesystem boundary is present
77  * We use a fixed fsid for a referral
78  */
79 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
80 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
81 
82 static __be32
83 check_filename(char *str, int len)
84 {
85 	int i;
86 
87 	if (len == 0)
88 		return nfserr_inval;
89 	if (isdotent(str, len))
90 		return nfserr_badname;
91 	for (i = 0; i < len; i++)
92 		if (str[i] == '/')
93 			return nfserr_badname;
94 	return 0;
95 }
96 
97 #define DECODE_HEAD				\
98 	__be32 *p;				\
99 	__be32 status
100 #define DECODE_TAIL				\
101 	status = 0;				\
102 out:						\
103 	return status;				\
104 xdr_error:					\
105 	dprintk("NFSD: xdr error (%s:%d)\n",	\
106 			__FILE__, __LINE__);	\
107 	status = nfserr_bad_xdr;		\
108 	goto out
109 
110 #define READMEM(x,nbytes) do {			\
111 	x = (char *)p;				\
112 	p += XDR_QUADLEN(nbytes);		\
113 } while (0)
114 #define SAVEMEM(x,nbytes) do {			\
115 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
116  		savemem(argp, p, nbytes) :	\
117  		(char *)p)) {			\
118 		dprintk("NFSD: xdr error (%s:%d)\n", \
119 				__FILE__, __LINE__); \
120 		goto xdr_error;			\
121 		}				\
122 	p += XDR_QUADLEN(nbytes);		\
123 } while (0)
124 #define COPYMEM(x,nbytes) do {			\
125 	memcpy((x), p, nbytes);			\
126 	p += XDR_QUADLEN(nbytes);		\
127 } while (0)
128 
129 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
130 #define READ_BUF(nbytes)  do {			\
131 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
132 		p = argp->p;			\
133 		argp->p += XDR_QUADLEN(nbytes);	\
134 	} else if (!(p = read_buf(argp, nbytes))) { \
135 		dprintk("NFSD: xdr error (%s:%d)\n", \
136 				__FILE__, __LINE__); \
137 		goto xdr_error;			\
138 	}					\
139 } while (0)
140 
141 static void next_decode_page(struct nfsd4_compoundargs *argp)
142 {
143 	argp->p = page_address(argp->pagelist[0]);
144 	argp->pagelist++;
145 	if (argp->pagelen < PAGE_SIZE) {
146 		argp->end = argp->p + XDR_QUADLEN(argp->pagelen);
147 		argp->pagelen = 0;
148 	} else {
149 		argp->end = argp->p + (PAGE_SIZE>>2);
150 		argp->pagelen -= PAGE_SIZE;
151 	}
152 }
153 
154 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
155 {
156 	/* We want more bytes than seem to be available.
157 	 * Maybe we need a new page, maybe we have just run out
158 	 */
159 	unsigned int avail = (char *)argp->end - (char *)argp->p;
160 	__be32 *p;
161 
162 	if (argp->pagelen == 0) {
163 		struct kvec *vec = &argp->rqstp->rq_arg.tail[0];
164 
165 		if (!argp->tail) {
166 			argp->tail = true;
167 			avail = vec->iov_len;
168 			argp->p = vec->iov_base;
169 			argp->end = vec->iov_base + avail;
170 		}
171 
172 		if (avail < nbytes)
173 			return NULL;
174 
175 		p = argp->p;
176 		argp->p += XDR_QUADLEN(nbytes);
177 		return p;
178 	}
179 
180 	if (avail + argp->pagelen < nbytes)
181 		return NULL;
182 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
183 		return NULL;
184 	/* ok, we can do it with the current plus the next page */
185 	if (nbytes <= sizeof(argp->tmp))
186 		p = argp->tmp;
187 	else {
188 		kfree(argp->tmpp);
189 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
190 		if (!p)
191 			return NULL;
192 
193 	}
194 	/*
195 	 * The following memcpy is safe because read_buf is always
196 	 * called with nbytes > avail, and the two cases above both
197 	 * guarantee p points to at least nbytes bytes.
198 	 */
199 	memcpy(p, argp->p, avail);
200 	next_decode_page(argp);
201 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
202 	argp->p += XDR_QUADLEN(nbytes - avail);
203 	return p;
204 }
205 
206 static int zero_clientid(clientid_t *clid)
207 {
208 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
209 }
210 
211 /**
212  * svcxdr_tmpalloc - allocate memory to be freed after compound processing
213  * @argp: NFSv4 compound argument structure
214  * @p: pointer to be freed (with kfree())
215  *
216  * Marks @p to be freed when processing the compound operation
217  * described in @argp finishes.
218  */
219 static void *
220 svcxdr_tmpalloc(struct nfsd4_compoundargs *argp, u32 len)
221 {
222 	struct svcxdr_tmpbuf *tb;
223 
224 	tb = kmalloc(sizeof(*tb) + len, GFP_KERNEL);
225 	if (!tb)
226 		return NULL;
227 	tb->next = argp->to_free;
228 	argp->to_free = tb;
229 	return tb->buf;
230 }
231 
232 /*
233  * For xdr strings that need to be passed to other kernel api's
234  * as null-terminated strings.
235  *
236  * Note null-terminating in place usually isn't safe since the
237  * buffer might end on a page boundary.
238  */
239 static char *
240 svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len)
241 {
242 	char *p = svcxdr_tmpalloc(argp, len + 1);
243 
244 	if (!p)
245 		return NULL;
246 	memcpy(p, buf, len);
247 	p[len] = '\0';
248 	return p;
249 }
250 
251 /**
252  * savemem - duplicate a chunk of memory for later processing
253  * @argp: NFSv4 compound argument structure to be freed with
254  * @p: pointer to be duplicated
255  * @nbytes: length to be duplicated
256  *
257  * Returns a pointer to a copy of @nbytes bytes of memory at @p
258  * that are preserved until processing of the NFSv4 compound
259  * operation described by @argp finishes.
260  */
261 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
262 {
263 	void *ret;
264 
265 	ret = svcxdr_tmpalloc(argp, nbytes);
266 	if (!ret)
267 		return NULL;
268 	memcpy(ret, p, nbytes);
269 	return ret;
270 }
271 
272 static __be32
273 nfsd4_decode_time(struct nfsd4_compoundargs *argp, struct timespec64 *tv)
274 {
275 	DECODE_HEAD;
276 
277 	READ_BUF(12);
278 	p = xdr_decode_hyper(p, &tv->tv_sec);
279 	tv->tv_nsec = be32_to_cpup(p++);
280 	if (tv->tv_nsec >= (u32)1000000000)
281 		return nfserr_inval;
282 
283 	DECODE_TAIL;
284 }
285 
286 static __be32
287 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
288 {
289 	u32 bmlen;
290 	DECODE_HEAD;
291 
292 	bmval[0] = 0;
293 	bmval[1] = 0;
294 	bmval[2] = 0;
295 
296 	READ_BUF(4);
297 	bmlen = be32_to_cpup(p++);
298 	if (bmlen > 1000)
299 		goto xdr_error;
300 
301 	READ_BUF(bmlen << 2);
302 	if (bmlen > 0)
303 		bmval[0] = be32_to_cpup(p++);
304 	if (bmlen > 1)
305 		bmval[1] = be32_to_cpup(p++);
306 	if (bmlen > 2)
307 		bmval[2] = be32_to_cpup(p++);
308 
309 	DECODE_TAIL;
310 }
311 
312 static __be32
313 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
314 		   struct iattr *iattr, struct nfs4_acl **acl,
315 		   struct xdr_netobj *label, int *umask)
316 {
317 	int expected_len, len = 0;
318 	u32 dummy32;
319 	char *buf;
320 
321 	DECODE_HEAD;
322 	iattr->ia_valid = 0;
323 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
324 		return status;
325 
326 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
327 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
328 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2) {
329 		if (nfsd_attrs_supported(argp->minorversion, bmval))
330 			return nfserr_inval;
331 		return nfserr_attrnotsupp;
332 	}
333 
334 	READ_BUF(4);
335 	expected_len = be32_to_cpup(p++);
336 
337 	if (bmval[0] & FATTR4_WORD0_SIZE) {
338 		READ_BUF(8);
339 		len += 8;
340 		p = xdr_decode_hyper(p, &iattr->ia_size);
341 		iattr->ia_valid |= ATTR_SIZE;
342 	}
343 	if (bmval[0] & FATTR4_WORD0_ACL) {
344 		u32 nace;
345 		struct nfs4_ace *ace;
346 
347 		READ_BUF(4); len += 4;
348 		nace = be32_to_cpup(p++);
349 
350 		if (nace > NFS4_ACL_MAX)
351 			return nfserr_fbig;
352 
353 		*acl = svcxdr_tmpalloc(argp, nfs4_acl_bytes(nace));
354 		if (*acl == NULL)
355 			return nfserr_jukebox;
356 
357 		(*acl)->naces = nace;
358 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
359 			READ_BUF(16); len += 16;
360 			ace->type = be32_to_cpup(p++);
361 			ace->flag = be32_to_cpup(p++);
362 			ace->access_mask = be32_to_cpup(p++);
363 			dummy32 = be32_to_cpup(p++);
364 			READ_BUF(dummy32);
365 			len += XDR_QUADLEN(dummy32) << 2;
366 			READMEM(buf, dummy32);
367 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
368 			status = nfs_ok;
369 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
370 				;
371 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
372 				status = nfsd_map_name_to_gid(argp->rqstp,
373 						buf, dummy32, &ace->who_gid);
374 			else
375 				status = nfsd_map_name_to_uid(argp->rqstp,
376 						buf, dummy32, &ace->who_uid);
377 			if (status)
378 				return status;
379 		}
380 	} else
381 		*acl = NULL;
382 	if (bmval[1] & FATTR4_WORD1_MODE) {
383 		READ_BUF(4);
384 		len += 4;
385 		iattr->ia_mode = be32_to_cpup(p++);
386 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
387 		iattr->ia_valid |= ATTR_MODE;
388 	}
389 	if (bmval[1] & FATTR4_WORD1_OWNER) {
390 		READ_BUF(4);
391 		len += 4;
392 		dummy32 = be32_to_cpup(p++);
393 		READ_BUF(dummy32);
394 		len += (XDR_QUADLEN(dummy32) << 2);
395 		READMEM(buf, dummy32);
396 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
397 			return status;
398 		iattr->ia_valid |= ATTR_UID;
399 	}
400 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
401 		READ_BUF(4);
402 		len += 4;
403 		dummy32 = be32_to_cpup(p++);
404 		READ_BUF(dummy32);
405 		len += (XDR_QUADLEN(dummy32) << 2);
406 		READMEM(buf, dummy32);
407 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
408 			return status;
409 		iattr->ia_valid |= ATTR_GID;
410 	}
411 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
412 		READ_BUF(4);
413 		len += 4;
414 		dummy32 = be32_to_cpup(p++);
415 		switch (dummy32) {
416 		case NFS4_SET_TO_CLIENT_TIME:
417 			len += 12;
418 			status = nfsd4_decode_time(argp, &iattr->ia_atime);
419 			if (status)
420 				return status;
421 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
422 			break;
423 		case NFS4_SET_TO_SERVER_TIME:
424 			iattr->ia_valid |= ATTR_ATIME;
425 			break;
426 		default:
427 			goto xdr_error;
428 		}
429 	}
430 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
431 		READ_BUF(4);
432 		len += 4;
433 		dummy32 = be32_to_cpup(p++);
434 		switch (dummy32) {
435 		case NFS4_SET_TO_CLIENT_TIME:
436 			len += 12;
437 			status = nfsd4_decode_time(argp, &iattr->ia_mtime);
438 			if (status)
439 				return status;
440 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
441 			break;
442 		case NFS4_SET_TO_SERVER_TIME:
443 			iattr->ia_valid |= ATTR_MTIME;
444 			break;
445 		default:
446 			goto xdr_error;
447 		}
448 	}
449 
450 	label->len = 0;
451 	if (IS_ENABLED(CONFIG_NFSD_V4_SECURITY_LABEL) &&
452 	    bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
453 		READ_BUF(4);
454 		len += 4;
455 		dummy32 = be32_to_cpup(p++); /* lfs: we don't use it */
456 		READ_BUF(4);
457 		len += 4;
458 		dummy32 = be32_to_cpup(p++); /* pi: we don't use it either */
459 		READ_BUF(4);
460 		len += 4;
461 		dummy32 = be32_to_cpup(p++);
462 		READ_BUF(dummy32);
463 		if (dummy32 > NFS4_MAXLABELLEN)
464 			return nfserr_badlabel;
465 		len += (XDR_QUADLEN(dummy32) << 2);
466 		READMEM(buf, dummy32);
467 		label->len = dummy32;
468 		label->data = svcxdr_dupstr(argp, buf, dummy32);
469 		if (!label->data)
470 			return nfserr_jukebox;
471 	}
472 	if (bmval[2] & FATTR4_WORD2_MODE_UMASK) {
473 		if (!umask)
474 			goto xdr_error;
475 		READ_BUF(8);
476 		len += 8;
477 		dummy32 = be32_to_cpup(p++);
478 		iattr->ia_mode = dummy32 & (S_IFMT | S_IALLUGO);
479 		dummy32 = be32_to_cpup(p++);
480 		*umask = dummy32 & S_IRWXUGO;
481 		iattr->ia_valid |= ATTR_MODE;
482 	}
483 	if (len != expected_len)
484 		goto xdr_error;
485 
486 	DECODE_TAIL;
487 }
488 
489 static __be32
490 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
491 {
492 	DECODE_HEAD;
493 
494 	READ_BUF(sizeof(stateid_t));
495 	sid->si_generation = be32_to_cpup(p++);
496 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
497 
498 	DECODE_TAIL;
499 }
500 
501 static __be32
502 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
503 {
504 	DECODE_HEAD;
505 
506 	READ_BUF(4);
507 	access->ac_req_access = be32_to_cpup(p++);
508 
509 	DECODE_TAIL;
510 }
511 
512 static __be32 nfsd4_decode_cb_sec(struct nfsd4_compoundargs *argp, struct nfsd4_cb_sec *cbs)
513 {
514 	DECODE_HEAD;
515 	struct user_namespace *userns = nfsd_user_namespace(argp->rqstp);
516 	u32 dummy, uid, gid;
517 	char *machine_name;
518 	int i;
519 	int nr_secflavs;
520 
521 	/* callback_sec_params4 */
522 	READ_BUF(4);
523 	nr_secflavs = be32_to_cpup(p++);
524 	if (nr_secflavs)
525 		cbs->flavor = (u32)(-1);
526 	else
527 		/* Is this legal? Be generous, take it to mean AUTH_NONE: */
528 		cbs->flavor = 0;
529 	for (i = 0; i < nr_secflavs; ++i) {
530 		READ_BUF(4);
531 		dummy = be32_to_cpup(p++);
532 		switch (dummy) {
533 		case RPC_AUTH_NULL:
534 			/* Nothing to read */
535 			if (cbs->flavor == (u32)(-1))
536 				cbs->flavor = RPC_AUTH_NULL;
537 			break;
538 		case RPC_AUTH_UNIX:
539 			READ_BUF(8);
540 			/* stamp */
541 			dummy = be32_to_cpup(p++);
542 
543 			/* machine name */
544 			dummy = be32_to_cpup(p++);
545 			READ_BUF(dummy);
546 			SAVEMEM(machine_name, dummy);
547 
548 			/* uid, gid */
549 			READ_BUF(8);
550 			uid = be32_to_cpup(p++);
551 			gid = be32_to_cpup(p++);
552 
553 			/* more gids */
554 			READ_BUF(4);
555 			dummy = be32_to_cpup(p++);
556 			READ_BUF(dummy * 4);
557 			if (cbs->flavor == (u32)(-1)) {
558 				kuid_t kuid = make_kuid(userns, uid);
559 				kgid_t kgid = make_kgid(userns, gid);
560 				if (uid_valid(kuid) && gid_valid(kgid)) {
561 					cbs->uid = kuid;
562 					cbs->gid = kgid;
563 					cbs->flavor = RPC_AUTH_UNIX;
564 				} else {
565 					dprintk("RPC_AUTH_UNIX with invalid"
566 						"uid or gid ignoring!\n");
567 				}
568 			}
569 			break;
570 		case RPC_AUTH_GSS:
571 			dprintk("RPC_AUTH_GSS callback secflavor "
572 				"not supported!\n");
573 			READ_BUF(8);
574 			/* gcbp_service */
575 			dummy = be32_to_cpup(p++);
576 			/* gcbp_handle_from_server */
577 			dummy = be32_to_cpup(p++);
578 			READ_BUF(dummy);
579 			p += XDR_QUADLEN(dummy);
580 			/* gcbp_handle_from_client */
581 			READ_BUF(4);
582 			dummy = be32_to_cpup(p++);
583 			READ_BUF(dummy);
584 			break;
585 		default:
586 			dprintk("Illegal callback secflavor\n");
587 			return nfserr_inval;
588 		}
589 	}
590 	DECODE_TAIL;
591 }
592 
593 static __be32 nfsd4_decode_backchannel_ctl(struct nfsd4_compoundargs *argp, struct nfsd4_backchannel_ctl *bc)
594 {
595 	DECODE_HEAD;
596 
597 	READ_BUF(4);
598 	bc->bc_cb_program = be32_to_cpup(p++);
599 	nfsd4_decode_cb_sec(argp, &bc->bc_cb_sec);
600 
601 	DECODE_TAIL;
602 }
603 
604 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
605 {
606 	DECODE_HEAD;
607 
608 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
609 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
610 	bcts->dir = be32_to_cpup(p++);
611 	/* XXX: skipping ctsa_use_conn_in_rdma_mode.  Perhaps Tom Tucker
612 	 * could help us figure out we should be using it. */
613 	DECODE_TAIL;
614 }
615 
616 static __be32
617 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
618 {
619 	DECODE_HEAD;
620 
621 	READ_BUF(4);
622 	close->cl_seqid = be32_to_cpup(p++);
623 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
624 
625 	DECODE_TAIL;
626 }
627 
628 
629 static __be32
630 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
631 {
632 	DECODE_HEAD;
633 
634 	READ_BUF(12);
635 	p = xdr_decode_hyper(p, &commit->co_offset);
636 	commit->co_count = be32_to_cpup(p++);
637 
638 	DECODE_TAIL;
639 }
640 
641 static __be32
642 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
643 {
644 	DECODE_HEAD;
645 
646 	READ_BUF(4);
647 	create->cr_type = be32_to_cpup(p++);
648 	switch (create->cr_type) {
649 	case NF4LNK:
650 		READ_BUF(4);
651 		create->cr_datalen = be32_to_cpup(p++);
652 		READ_BUF(create->cr_datalen);
653 		create->cr_data = svcxdr_dupstr(argp, p, create->cr_datalen);
654 		if (!create->cr_data)
655 			return nfserr_jukebox;
656 		break;
657 	case NF4BLK:
658 	case NF4CHR:
659 		READ_BUF(8);
660 		create->cr_specdata1 = be32_to_cpup(p++);
661 		create->cr_specdata2 = be32_to_cpup(p++);
662 		break;
663 	case NF4SOCK:
664 	case NF4FIFO:
665 	case NF4DIR:
666 	default:
667 		break;
668 	}
669 
670 	READ_BUF(4);
671 	create->cr_namelen = be32_to_cpup(p++);
672 	READ_BUF(create->cr_namelen);
673 	SAVEMEM(create->cr_name, create->cr_namelen);
674 	if ((status = check_filename(create->cr_name, create->cr_namelen)))
675 		return status;
676 
677 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
678 				    &create->cr_acl, &create->cr_label,
679 				    &create->cr_umask);
680 	if (status)
681 		goto out;
682 
683 	DECODE_TAIL;
684 }
685 
686 static inline __be32
687 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
688 {
689 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
690 }
691 
692 static inline __be32
693 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
694 {
695 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
696 }
697 
698 static __be32
699 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
700 {
701 	DECODE_HEAD;
702 
703 	READ_BUF(4);
704 	link->li_namelen = be32_to_cpup(p++);
705 	READ_BUF(link->li_namelen);
706 	SAVEMEM(link->li_name, link->li_namelen);
707 	if ((status = check_filename(link->li_name, link->li_namelen)))
708 		return status;
709 
710 	DECODE_TAIL;
711 }
712 
713 static __be32
714 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
715 {
716 	DECODE_HEAD;
717 
718 	/*
719 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
720 	*/
721 	READ_BUF(28);
722 	lock->lk_type = be32_to_cpup(p++);
723 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
724 		goto xdr_error;
725 	lock->lk_reclaim = be32_to_cpup(p++);
726 	p = xdr_decode_hyper(p, &lock->lk_offset);
727 	p = xdr_decode_hyper(p, &lock->lk_length);
728 	lock->lk_is_new = be32_to_cpup(p++);
729 
730 	if (lock->lk_is_new) {
731 		READ_BUF(4);
732 		lock->lk_new_open_seqid = be32_to_cpup(p++);
733 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
734 		if (status)
735 			return status;
736 		READ_BUF(8 + sizeof(clientid_t));
737 		lock->lk_new_lock_seqid = be32_to_cpup(p++);
738 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
739 		lock->lk_new_owner.len = be32_to_cpup(p++);
740 		READ_BUF(lock->lk_new_owner.len);
741 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
742 	} else {
743 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
744 		if (status)
745 			return status;
746 		READ_BUF(4);
747 		lock->lk_old_lock_seqid = be32_to_cpup(p++);
748 	}
749 
750 	DECODE_TAIL;
751 }
752 
753 static __be32
754 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
755 {
756 	DECODE_HEAD;
757 
758 	READ_BUF(32);
759 	lockt->lt_type = be32_to_cpup(p++);
760 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
761 		goto xdr_error;
762 	p = xdr_decode_hyper(p, &lockt->lt_offset);
763 	p = xdr_decode_hyper(p, &lockt->lt_length);
764 	COPYMEM(&lockt->lt_clientid, 8);
765 	lockt->lt_owner.len = be32_to_cpup(p++);
766 	READ_BUF(lockt->lt_owner.len);
767 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
768 
769 	DECODE_TAIL;
770 }
771 
772 static __be32
773 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
774 {
775 	DECODE_HEAD;
776 
777 	READ_BUF(8);
778 	locku->lu_type = be32_to_cpup(p++);
779 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
780 		goto xdr_error;
781 	locku->lu_seqid = be32_to_cpup(p++);
782 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
783 	if (status)
784 		return status;
785 	READ_BUF(16);
786 	p = xdr_decode_hyper(p, &locku->lu_offset);
787 	p = xdr_decode_hyper(p, &locku->lu_length);
788 
789 	DECODE_TAIL;
790 }
791 
792 static __be32
793 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
794 {
795 	DECODE_HEAD;
796 
797 	READ_BUF(4);
798 	lookup->lo_len = be32_to_cpup(p++);
799 	READ_BUF(lookup->lo_len);
800 	SAVEMEM(lookup->lo_name, lookup->lo_len);
801 	if ((status = check_filename(lookup->lo_name, lookup->lo_len)))
802 		return status;
803 
804 	DECODE_TAIL;
805 }
806 
807 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
808 {
809 	__be32 *p;
810 	u32 w;
811 
812 	READ_BUF(4);
813 	w = be32_to_cpup(p++);
814 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
815 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
816 	if (deleg_when)
817 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
818 
819 	switch (w & NFS4_SHARE_ACCESS_MASK) {
820 	case NFS4_SHARE_ACCESS_READ:
821 	case NFS4_SHARE_ACCESS_WRITE:
822 	case NFS4_SHARE_ACCESS_BOTH:
823 		break;
824 	default:
825 		return nfserr_bad_xdr;
826 	}
827 	w &= ~NFS4_SHARE_ACCESS_MASK;
828 	if (!w)
829 		return nfs_ok;
830 	if (!argp->minorversion)
831 		return nfserr_bad_xdr;
832 	switch (w & NFS4_SHARE_WANT_MASK) {
833 	case NFS4_SHARE_WANT_NO_PREFERENCE:
834 	case NFS4_SHARE_WANT_READ_DELEG:
835 	case NFS4_SHARE_WANT_WRITE_DELEG:
836 	case NFS4_SHARE_WANT_ANY_DELEG:
837 	case NFS4_SHARE_WANT_NO_DELEG:
838 	case NFS4_SHARE_WANT_CANCEL:
839 		break;
840 	default:
841 		return nfserr_bad_xdr;
842 	}
843 	w &= ~NFS4_SHARE_WANT_MASK;
844 	if (!w)
845 		return nfs_ok;
846 
847 	if (!deleg_when)	/* open_downgrade */
848 		return nfserr_inval;
849 	switch (w) {
850 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
851 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
852 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
853 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
854 		return nfs_ok;
855 	}
856 xdr_error:
857 	return nfserr_bad_xdr;
858 }
859 
860 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
861 {
862 	__be32 *p;
863 
864 	READ_BUF(4);
865 	*x = be32_to_cpup(p++);
866 	/* Note: unlinke access bits, deny bits may be zero. */
867 	if (*x & ~NFS4_SHARE_DENY_BOTH)
868 		return nfserr_bad_xdr;
869 	return nfs_ok;
870 xdr_error:
871 	return nfserr_bad_xdr;
872 }
873 
874 static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
875 {
876 	__be32 *p;
877 
878 	READ_BUF(4);
879 	o->len = be32_to_cpup(p++);
880 
881 	if (o->len == 0 || o->len > NFS4_OPAQUE_LIMIT)
882 		return nfserr_bad_xdr;
883 
884 	READ_BUF(o->len);
885 	SAVEMEM(o->data, o->len);
886 	return nfs_ok;
887 xdr_error:
888 	return nfserr_bad_xdr;
889 }
890 
891 static __be32
892 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
893 {
894 	DECODE_HEAD;
895 	u32 dummy;
896 
897 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
898 	open->op_iattr.ia_valid = 0;
899 	open->op_openowner = NULL;
900 
901 	open->op_xdr_error = 0;
902 	/* seqid, share_access, share_deny, clientid, ownerlen */
903 	READ_BUF(4);
904 	open->op_seqid = be32_to_cpup(p++);
905 	/* decode, yet ignore deleg_when until supported */
906 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
907 					   &open->op_deleg_want, &dummy);
908 	if (status)
909 		goto xdr_error;
910 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
911 	if (status)
912 		goto xdr_error;
913 	READ_BUF(sizeof(clientid_t));
914 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
915 	status = nfsd4_decode_opaque(argp, &open->op_owner);
916 	if (status)
917 		goto xdr_error;
918 	READ_BUF(4);
919 	open->op_create = be32_to_cpup(p++);
920 	switch (open->op_create) {
921 	case NFS4_OPEN_NOCREATE:
922 		break;
923 	case NFS4_OPEN_CREATE:
924 		READ_BUF(4);
925 		open->op_createmode = be32_to_cpup(p++);
926 		switch (open->op_createmode) {
927 		case NFS4_CREATE_UNCHECKED:
928 		case NFS4_CREATE_GUARDED:
929 			status = nfsd4_decode_fattr(argp, open->op_bmval,
930 				&open->op_iattr, &open->op_acl, &open->op_label,
931 				&open->op_umask);
932 			if (status)
933 				goto out;
934 			break;
935 		case NFS4_CREATE_EXCLUSIVE:
936 			READ_BUF(NFS4_VERIFIER_SIZE);
937 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
938 			break;
939 		case NFS4_CREATE_EXCLUSIVE4_1:
940 			if (argp->minorversion < 1)
941 				goto xdr_error;
942 			READ_BUF(NFS4_VERIFIER_SIZE);
943 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
944 			status = nfsd4_decode_fattr(argp, open->op_bmval,
945 				&open->op_iattr, &open->op_acl, &open->op_label,
946 				&open->op_umask);
947 			if (status)
948 				goto out;
949 			break;
950 		default:
951 			goto xdr_error;
952 		}
953 		break;
954 	default:
955 		goto xdr_error;
956 	}
957 
958 	/* open_claim */
959 	READ_BUF(4);
960 	open->op_claim_type = be32_to_cpup(p++);
961 	switch (open->op_claim_type) {
962 	case NFS4_OPEN_CLAIM_NULL:
963 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
964 		READ_BUF(4);
965 		open->op_fname.len = be32_to_cpup(p++);
966 		READ_BUF(open->op_fname.len);
967 		SAVEMEM(open->op_fname.data, open->op_fname.len);
968 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
969 			return status;
970 		break;
971 	case NFS4_OPEN_CLAIM_PREVIOUS:
972 		READ_BUF(4);
973 		open->op_delegate_type = be32_to_cpup(p++);
974 		break;
975 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
976 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
977 		if (status)
978 			return status;
979 		READ_BUF(4);
980 		open->op_fname.len = be32_to_cpup(p++);
981 		READ_BUF(open->op_fname.len);
982 		SAVEMEM(open->op_fname.data, open->op_fname.len);
983 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
984 			return status;
985 		break;
986 	case NFS4_OPEN_CLAIM_FH:
987 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
988 		if (argp->minorversion < 1)
989 			goto xdr_error;
990 		/* void */
991 		break;
992 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
993 		if (argp->minorversion < 1)
994 			goto xdr_error;
995 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
996 		if (status)
997 			return status;
998 		break;
999 	default:
1000 		goto xdr_error;
1001 	}
1002 
1003 	DECODE_TAIL;
1004 }
1005 
1006 static __be32
1007 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
1008 {
1009 	DECODE_HEAD;
1010 
1011 	if (argp->minorversion >= 1)
1012 		return nfserr_notsupp;
1013 
1014 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
1015 	if (status)
1016 		return status;
1017 	READ_BUF(4);
1018 	open_conf->oc_seqid = be32_to_cpup(p++);
1019 
1020 	DECODE_TAIL;
1021 }
1022 
1023 static __be32
1024 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
1025 {
1026 	DECODE_HEAD;
1027 
1028 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
1029 	if (status)
1030 		return status;
1031 	READ_BUF(4);
1032 	open_down->od_seqid = be32_to_cpup(p++);
1033 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
1034 					   &open_down->od_deleg_want, NULL);
1035 	if (status)
1036 		return status;
1037 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
1038 	if (status)
1039 		return status;
1040 	DECODE_TAIL;
1041 }
1042 
1043 static __be32
1044 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
1045 {
1046 	DECODE_HEAD;
1047 
1048 	READ_BUF(4);
1049 	putfh->pf_fhlen = be32_to_cpup(p++);
1050 	if (putfh->pf_fhlen > NFS4_FHSIZE)
1051 		goto xdr_error;
1052 	READ_BUF(putfh->pf_fhlen);
1053 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
1054 
1055 	DECODE_TAIL;
1056 }
1057 
1058 static __be32
1059 nfsd4_decode_putpubfh(struct nfsd4_compoundargs *argp, void *p)
1060 {
1061 	if (argp->minorversion == 0)
1062 		return nfs_ok;
1063 	return nfserr_notsupp;
1064 }
1065 
1066 static __be32
1067 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
1068 {
1069 	DECODE_HEAD;
1070 
1071 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
1072 	if (status)
1073 		return status;
1074 	READ_BUF(12);
1075 	p = xdr_decode_hyper(p, &read->rd_offset);
1076 	read->rd_length = be32_to_cpup(p++);
1077 
1078 	DECODE_TAIL;
1079 }
1080 
1081 static __be32
1082 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
1083 {
1084 	DECODE_HEAD;
1085 
1086 	READ_BUF(24);
1087 	p = xdr_decode_hyper(p, &readdir->rd_cookie);
1088 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
1089 	readdir->rd_dircount = be32_to_cpup(p++);
1090 	readdir->rd_maxcount = be32_to_cpup(p++);
1091 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
1092 		goto out;
1093 
1094 	DECODE_TAIL;
1095 }
1096 
1097 static __be32
1098 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
1099 {
1100 	DECODE_HEAD;
1101 
1102 	READ_BUF(4);
1103 	remove->rm_namelen = be32_to_cpup(p++);
1104 	READ_BUF(remove->rm_namelen);
1105 	SAVEMEM(remove->rm_name, remove->rm_namelen);
1106 	if ((status = check_filename(remove->rm_name, remove->rm_namelen)))
1107 		return status;
1108 
1109 	DECODE_TAIL;
1110 }
1111 
1112 static __be32
1113 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
1114 {
1115 	DECODE_HEAD;
1116 
1117 	READ_BUF(4);
1118 	rename->rn_snamelen = be32_to_cpup(p++);
1119 	READ_BUF(rename->rn_snamelen);
1120 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1121 	READ_BUF(4);
1122 	rename->rn_tnamelen = be32_to_cpup(p++);
1123 	READ_BUF(rename->rn_tnamelen);
1124 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1125 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1126 		return status;
1127 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1128 		return status;
1129 
1130 	DECODE_TAIL;
1131 }
1132 
1133 static __be32
1134 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1135 {
1136 	DECODE_HEAD;
1137 
1138 	if (argp->minorversion >= 1)
1139 		return nfserr_notsupp;
1140 
1141 	READ_BUF(sizeof(clientid_t));
1142 	COPYMEM(clientid, sizeof(clientid_t));
1143 
1144 	DECODE_TAIL;
1145 }
1146 
1147 static __be32
1148 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1149 		     struct nfsd4_secinfo *secinfo)
1150 {
1151 	DECODE_HEAD;
1152 
1153 	READ_BUF(4);
1154 	secinfo->si_namelen = be32_to_cpup(p++);
1155 	READ_BUF(secinfo->si_namelen);
1156 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1157 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1158 	if (status)
1159 		return status;
1160 	DECODE_TAIL;
1161 }
1162 
1163 static __be32
1164 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1165 		     struct nfsd4_secinfo_no_name *sin)
1166 {
1167 	DECODE_HEAD;
1168 
1169 	READ_BUF(4);
1170 	sin->sin_style = be32_to_cpup(p++);
1171 	DECODE_TAIL;
1172 }
1173 
1174 static __be32
1175 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1176 {
1177 	__be32 status;
1178 
1179 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1180 	if (status)
1181 		return status;
1182 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1183 				  &setattr->sa_acl, &setattr->sa_label, NULL);
1184 }
1185 
1186 static __be32
1187 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1188 {
1189 	DECODE_HEAD;
1190 
1191 	if (argp->minorversion >= 1)
1192 		return nfserr_notsupp;
1193 
1194 	READ_BUF(NFS4_VERIFIER_SIZE);
1195 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1196 
1197 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1198 	if (status)
1199 		return nfserr_bad_xdr;
1200 	READ_BUF(8);
1201 	setclientid->se_callback_prog = be32_to_cpup(p++);
1202 	setclientid->se_callback_netid_len = be32_to_cpup(p++);
1203 	READ_BUF(setclientid->se_callback_netid_len);
1204 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1205 	READ_BUF(4);
1206 	setclientid->se_callback_addr_len = be32_to_cpup(p++);
1207 
1208 	READ_BUF(setclientid->se_callback_addr_len);
1209 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1210 	READ_BUF(4);
1211 	setclientid->se_callback_ident = be32_to_cpup(p++);
1212 
1213 	DECODE_TAIL;
1214 }
1215 
1216 static __be32
1217 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1218 {
1219 	DECODE_HEAD;
1220 
1221 	if (argp->minorversion >= 1)
1222 		return nfserr_notsupp;
1223 
1224 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1225 	COPYMEM(&scd_c->sc_clientid, 8);
1226 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1227 
1228 	DECODE_TAIL;
1229 }
1230 
1231 /* Also used for NVERIFY */
1232 static __be32
1233 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1234 {
1235 	DECODE_HEAD;
1236 
1237 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1238 		goto out;
1239 
1240 	/* For convenience's sake, we compare raw xdr'd attributes in
1241 	 * nfsd4_proc_verify */
1242 
1243 	READ_BUF(4);
1244 	verify->ve_attrlen = be32_to_cpup(p++);
1245 	READ_BUF(verify->ve_attrlen);
1246 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1247 
1248 	DECODE_TAIL;
1249 }
1250 
1251 static __be32
1252 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1253 {
1254 	int avail;
1255 	int len;
1256 	DECODE_HEAD;
1257 
1258 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1259 	if (status)
1260 		return status;
1261 	READ_BUF(16);
1262 	p = xdr_decode_hyper(p, &write->wr_offset);
1263 	write->wr_stable_how = be32_to_cpup(p++);
1264 	if (write->wr_stable_how > NFS_FILE_SYNC)
1265 		goto xdr_error;
1266 	write->wr_buflen = be32_to_cpup(p++);
1267 
1268 	/* Sorry .. no magic macros for this.. *
1269 	 * READ_BUF(write->wr_buflen);
1270 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1271 	 */
1272 	avail = (char*)argp->end - (char*)argp->p;
1273 	if (avail + argp->pagelen < write->wr_buflen) {
1274 		dprintk("NFSD: xdr error (%s:%d)\n",
1275 				__FILE__, __LINE__);
1276 		goto xdr_error;
1277 	}
1278 	write->wr_head.iov_base = p;
1279 	write->wr_head.iov_len = avail;
1280 	write->wr_pagelist = argp->pagelist;
1281 
1282 	len = XDR_QUADLEN(write->wr_buflen) << 2;
1283 	if (len >= avail) {
1284 		int pages;
1285 
1286 		len -= avail;
1287 
1288 		pages = len >> PAGE_SHIFT;
1289 		argp->pagelist += pages;
1290 		argp->pagelen -= pages * PAGE_SIZE;
1291 		len -= pages * PAGE_SIZE;
1292 
1293 		next_decode_page(argp);
1294 	}
1295 	argp->p += XDR_QUADLEN(len);
1296 
1297 	DECODE_TAIL;
1298 }
1299 
1300 static __be32
1301 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1302 {
1303 	DECODE_HEAD;
1304 
1305 	if (argp->minorversion >= 1)
1306 		return nfserr_notsupp;
1307 
1308 	READ_BUF(12);
1309 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1310 	rlockowner->rl_owner.len = be32_to_cpup(p++);
1311 	READ_BUF(rlockowner->rl_owner.len);
1312 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1313 
1314 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1315 		return nfserr_inval;
1316 	DECODE_TAIL;
1317 }
1318 
1319 static __be32
1320 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1321 			 struct nfsd4_exchange_id *exid)
1322 {
1323 	int dummy, tmp;
1324 	DECODE_HEAD;
1325 
1326 	READ_BUF(NFS4_VERIFIER_SIZE);
1327 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1328 
1329 	status = nfsd4_decode_opaque(argp, &exid->clname);
1330 	if (status)
1331 		return nfserr_bad_xdr;
1332 
1333 	READ_BUF(4);
1334 	exid->flags = be32_to_cpup(p++);
1335 
1336 	/* Ignore state_protect4_a */
1337 	READ_BUF(4);
1338 	exid->spa_how = be32_to_cpup(p++);
1339 	switch (exid->spa_how) {
1340 	case SP4_NONE:
1341 		break;
1342 	case SP4_MACH_CRED:
1343 		/* spo_must_enforce */
1344 		status = nfsd4_decode_bitmap(argp,
1345 					exid->spo_must_enforce);
1346 		if (status)
1347 			goto out;
1348 		/* spo_must_allow */
1349 		status = nfsd4_decode_bitmap(argp, exid->spo_must_allow);
1350 		if (status)
1351 			goto out;
1352 		break;
1353 	case SP4_SSV:
1354 		/* ssp_ops */
1355 		READ_BUF(4);
1356 		dummy = be32_to_cpup(p++);
1357 		READ_BUF(dummy * 4);
1358 		p += dummy;
1359 
1360 		READ_BUF(4);
1361 		dummy = be32_to_cpup(p++);
1362 		READ_BUF(dummy * 4);
1363 		p += dummy;
1364 
1365 		/* ssp_hash_algs<> */
1366 		READ_BUF(4);
1367 		tmp = be32_to_cpup(p++);
1368 		while (tmp--) {
1369 			READ_BUF(4);
1370 			dummy = be32_to_cpup(p++);
1371 			READ_BUF(dummy);
1372 			p += XDR_QUADLEN(dummy);
1373 		}
1374 
1375 		/* ssp_encr_algs<> */
1376 		READ_BUF(4);
1377 		tmp = be32_to_cpup(p++);
1378 		while (tmp--) {
1379 			READ_BUF(4);
1380 			dummy = be32_to_cpup(p++);
1381 			READ_BUF(dummy);
1382 			p += XDR_QUADLEN(dummy);
1383 		}
1384 
1385 		/* ignore ssp_window and ssp_num_gss_handles: */
1386 		READ_BUF(8);
1387 		break;
1388 	default:
1389 		goto xdr_error;
1390 	}
1391 
1392 	READ_BUF(4);    /* nfs_impl_id4 array length */
1393 	dummy = be32_to_cpup(p++);
1394 
1395 	if (dummy > 1)
1396 		goto xdr_error;
1397 
1398 	if (dummy == 1) {
1399 		status = nfsd4_decode_opaque(argp, &exid->nii_domain);
1400 		if (status)
1401 			goto xdr_error;
1402 
1403 		/* nii_name */
1404 		status = nfsd4_decode_opaque(argp, &exid->nii_name);
1405 		if (status)
1406 			goto xdr_error;
1407 
1408 		/* nii_date */
1409 		status = nfsd4_decode_time(argp, &exid->nii_time);
1410 		if (status)
1411 			goto xdr_error;
1412 	}
1413 	DECODE_TAIL;
1414 }
1415 
1416 static __be32
1417 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1418 			    struct nfsd4_create_session *sess)
1419 {
1420 	DECODE_HEAD;
1421 	u32 dummy;
1422 
1423 	READ_BUF(16);
1424 	COPYMEM(&sess->clientid, 8);
1425 	sess->seqid = be32_to_cpup(p++);
1426 	sess->flags = be32_to_cpup(p++);
1427 
1428 	/* Fore channel attrs */
1429 	READ_BUF(28);
1430 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1431 	sess->fore_channel.maxreq_sz = be32_to_cpup(p++);
1432 	sess->fore_channel.maxresp_sz = be32_to_cpup(p++);
1433 	sess->fore_channel.maxresp_cached = be32_to_cpup(p++);
1434 	sess->fore_channel.maxops = be32_to_cpup(p++);
1435 	sess->fore_channel.maxreqs = be32_to_cpup(p++);
1436 	sess->fore_channel.nr_rdma_attrs = be32_to_cpup(p++);
1437 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1438 		READ_BUF(4);
1439 		sess->fore_channel.rdma_attrs = be32_to_cpup(p++);
1440 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1441 		dprintk("Too many fore channel attr bitmaps!\n");
1442 		goto xdr_error;
1443 	}
1444 
1445 	/* Back channel attrs */
1446 	READ_BUF(28);
1447 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1448 	sess->back_channel.maxreq_sz = be32_to_cpup(p++);
1449 	sess->back_channel.maxresp_sz = be32_to_cpup(p++);
1450 	sess->back_channel.maxresp_cached = be32_to_cpup(p++);
1451 	sess->back_channel.maxops = be32_to_cpup(p++);
1452 	sess->back_channel.maxreqs = be32_to_cpup(p++);
1453 	sess->back_channel.nr_rdma_attrs = be32_to_cpup(p++);
1454 	if (sess->back_channel.nr_rdma_attrs == 1) {
1455 		READ_BUF(4);
1456 		sess->back_channel.rdma_attrs = be32_to_cpup(p++);
1457 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1458 		dprintk("Too many back channel attr bitmaps!\n");
1459 		goto xdr_error;
1460 	}
1461 
1462 	READ_BUF(4);
1463 	sess->callback_prog = be32_to_cpup(p++);
1464 	nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1465 	DECODE_TAIL;
1466 }
1467 
1468 static __be32
1469 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1470 			     struct nfsd4_destroy_session *destroy_session)
1471 {
1472 	DECODE_HEAD;
1473 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1474 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1475 
1476 	DECODE_TAIL;
1477 }
1478 
1479 static __be32
1480 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1481 			  struct nfsd4_free_stateid *free_stateid)
1482 {
1483 	DECODE_HEAD;
1484 
1485 	READ_BUF(sizeof(stateid_t));
1486 	free_stateid->fr_stateid.si_generation = be32_to_cpup(p++);
1487 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1488 
1489 	DECODE_TAIL;
1490 }
1491 
1492 static __be32
1493 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1494 		      struct nfsd4_sequence *seq)
1495 {
1496 	DECODE_HEAD;
1497 
1498 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1499 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1500 	seq->seqid = be32_to_cpup(p++);
1501 	seq->slotid = be32_to_cpup(p++);
1502 	seq->maxslots = be32_to_cpup(p++);
1503 	seq->cachethis = be32_to_cpup(p++);
1504 
1505 	DECODE_TAIL;
1506 }
1507 
1508 static __be32
1509 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1510 {
1511 	int i;
1512 	__be32 *p, status;
1513 	struct nfsd4_test_stateid_id *stateid;
1514 
1515 	READ_BUF(4);
1516 	test_stateid->ts_num_ids = ntohl(*p++);
1517 
1518 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1519 
1520 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1521 		stateid = svcxdr_tmpalloc(argp, sizeof(*stateid));
1522 		if (!stateid) {
1523 			status = nfserrno(-ENOMEM);
1524 			goto out;
1525 		}
1526 
1527 		INIT_LIST_HEAD(&stateid->ts_id_list);
1528 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1529 
1530 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1531 		if (status)
1532 			goto out;
1533 	}
1534 
1535 	status = 0;
1536 out:
1537 	return status;
1538 xdr_error:
1539 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1540 	status = nfserr_bad_xdr;
1541 	goto out;
1542 }
1543 
1544 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1545 {
1546 	DECODE_HEAD;
1547 
1548 	READ_BUF(8);
1549 	COPYMEM(&dc->clientid, 8);
1550 
1551 	DECODE_TAIL;
1552 }
1553 
1554 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1555 {
1556 	DECODE_HEAD;
1557 
1558 	READ_BUF(4);
1559 	rc->rca_one_fs = be32_to_cpup(p++);
1560 
1561 	DECODE_TAIL;
1562 }
1563 
1564 #ifdef CONFIG_NFSD_PNFS
1565 static __be32
1566 nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp,
1567 		struct nfsd4_getdeviceinfo *gdev)
1568 {
1569 	DECODE_HEAD;
1570 	u32 num, i;
1571 
1572 	READ_BUF(sizeof(struct nfsd4_deviceid) + 3 * 4);
1573 	COPYMEM(&gdev->gd_devid, sizeof(struct nfsd4_deviceid));
1574 	gdev->gd_layout_type = be32_to_cpup(p++);
1575 	gdev->gd_maxcount = be32_to_cpup(p++);
1576 	num = be32_to_cpup(p++);
1577 	if (num) {
1578 		if (num > 1000)
1579 			goto xdr_error;
1580 		READ_BUF(4 * num);
1581 		gdev->gd_notify_types = be32_to_cpup(p++);
1582 		for (i = 1; i < num; i++) {
1583 			if (be32_to_cpup(p++)) {
1584 				status = nfserr_inval;
1585 				goto out;
1586 			}
1587 		}
1588 	}
1589 	DECODE_TAIL;
1590 }
1591 
1592 static __be32
1593 nfsd4_decode_layoutget(struct nfsd4_compoundargs *argp,
1594 		struct nfsd4_layoutget *lgp)
1595 {
1596 	DECODE_HEAD;
1597 
1598 	READ_BUF(36);
1599 	lgp->lg_signal = be32_to_cpup(p++);
1600 	lgp->lg_layout_type = be32_to_cpup(p++);
1601 	lgp->lg_seg.iomode = be32_to_cpup(p++);
1602 	p = xdr_decode_hyper(p, &lgp->lg_seg.offset);
1603 	p = xdr_decode_hyper(p, &lgp->lg_seg.length);
1604 	p = xdr_decode_hyper(p, &lgp->lg_minlength);
1605 
1606 	status = nfsd4_decode_stateid(argp, &lgp->lg_sid);
1607 	if (status)
1608 		return status;
1609 
1610 	READ_BUF(4);
1611 	lgp->lg_maxcount = be32_to_cpup(p++);
1612 
1613 	DECODE_TAIL;
1614 }
1615 
1616 static __be32
1617 nfsd4_decode_layoutcommit(struct nfsd4_compoundargs *argp,
1618 		struct nfsd4_layoutcommit *lcp)
1619 {
1620 	DECODE_HEAD;
1621 	u32 timechange;
1622 
1623 	READ_BUF(20);
1624 	p = xdr_decode_hyper(p, &lcp->lc_seg.offset);
1625 	p = xdr_decode_hyper(p, &lcp->lc_seg.length);
1626 	lcp->lc_reclaim = be32_to_cpup(p++);
1627 
1628 	status = nfsd4_decode_stateid(argp, &lcp->lc_sid);
1629 	if (status)
1630 		return status;
1631 
1632 	READ_BUF(4);
1633 	lcp->lc_newoffset = be32_to_cpup(p++);
1634 	if (lcp->lc_newoffset) {
1635 		READ_BUF(8);
1636 		p = xdr_decode_hyper(p, &lcp->lc_last_wr);
1637 	} else
1638 		lcp->lc_last_wr = 0;
1639 	READ_BUF(4);
1640 	timechange = be32_to_cpup(p++);
1641 	if (timechange) {
1642 		status = nfsd4_decode_time(argp, &lcp->lc_mtime);
1643 		if (status)
1644 			return status;
1645 	} else {
1646 		lcp->lc_mtime.tv_nsec = UTIME_NOW;
1647 	}
1648 	READ_BUF(8);
1649 	lcp->lc_layout_type = be32_to_cpup(p++);
1650 
1651 	/*
1652 	 * Save the layout update in XDR format and let the layout driver deal
1653 	 * with it later.
1654 	 */
1655 	lcp->lc_up_len = be32_to_cpup(p++);
1656 	if (lcp->lc_up_len > 0) {
1657 		READ_BUF(lcp->lc_up_len);
1658 		READMEM(lcp->lc_up_layout, lcp->lc_up_len);
1659 	}
1660 
1661 	DECODE_TAIL;
1662 }
1663 
1664 static __be32
1665 nfsd4_decode_layoutreturn(struct nfsd4_compoundargs *argp,
1666 		struct nfsd4_layoutreturn *lrp)
1667 {
1668 	DECODE_HEAD;
1669 
1670 	READ_BUF(16);
1671 	lrp->lr_reclaim = be32_to_cpup(p++);
1672 	lrp->lr_layout_type = be32_to_cpup(p++);
1673 	lrp->lr_seg.iomode = be32_to_cpup(p++);
1674 	lrp->lr_return_type = be32_to_cpup(p++);
1675 	if (lrp->lr_return_type == RETURN_FILE) {
1676 		READ_BUF(16);
1677 		p = xdr_decode_hyper(p, &lrp->lr_seg.offset);
1678 		p = xdr_decode_hyper(p, &lrp->lr_seg.length);
1679 
1680 		status = nfsd4_decode_stateid(argp, &lrp->lr_sid);
1681 		if (status)
1682 			return status;
1683 
1684 		READ_BUF(4);
1685 		lrp->lrf_body_len = be32_to_cpup(p++);
1686 		if (lrp->lrf_body_len > 0) {
1687 			READ_BUF(lrp->lrf_body_len);
1688 			READMEM(lrp->lrf_body, lrp->lrf_body_len);
1689 		}
1690 	} else {
1691 		lrp->lr_seg.offset = 0;
1692 		lrp->lr_seg.length = NFS4_MAX_UINT64;
1693 	}
1694 
1695 	DECODE_TAIL;
1696 }
1697 #endif /* CONFIG_NFSD_PNFS */
1698 
1699 static __be32
1700 nfsd4_decode_fallocate(struct nfsd4_compoundargs *argp,
1701 		       struct nfsd4_fallocate *fallocate)
1702 {
1703 	DECODE_HEAD;
1704 
1705 	status = nfsd4_decode_stateid(argp, &fallocate->falloc_stateid);
1706 	if (status)
1707 		return status;
1708 
1709 	READ_BUF(16);
1710 	p = xdr_decode_hyper(p, &fallocate->falloc_offset);
1711 	xdr_decode_hyper(p, &fallocate->falloc_length);
1712 
1713 	DECODE_TAIL;
1714 }
1715 
1716 static __be32
1717 nfsd4_decode_clone(struct nfsd4_compoundargs *argp, struct nfsd4_clone *clone)
1718 {
1719 	DECODE_HEAD;
1720 
1721 	status = nfsd4_decode_stateid(argp, &clone->cl_src_stateid);
1722 	if (status)
1723 		return status;
1724 	status = nfsd4_decode_stateid(argp, &clone->cl_dst_stateid);
1725 	if (status)
1726 		return status;
1727 
1728 	READ_BUF(8 + 8 + 8);
1729 	p = xdr_decode_hyper(p, &clone->cl_src_pos);
1730 	p = xdr_decode_hyper(p, &clone->cl_dst_pos);
1731 	p = xdr_decode_hyper(p, &clone->cl_count);
1732 	DECODE_TAIL;
1733 }
1734 
1735 static __be32
1736 nfsd4_decode_copy(struct nfsd4_compoundargs *argp, struct nfsd4_copy *copy)
1737 {
1738 	DECODE_HEAD;
1739 	unsigned int tmp;
1740 
1741 	status = nfsd4_decode_stateid(argp, &copy->cp_src_stateid);
1742 	if (status)
1743 		return status;
1744 	status = nfsd4_decode_stateid(argp, &copy->cp_dst_stateid);
1745 	if (status)
1746 		return status;
1747 
1748 	READ_BUF(8 + 8 + 8 + 4 + 4 + 4);
1749 	p = xdr_decode_hyper(p, &copy->cp_src_pos);
1750 	p = xdr_decode_hyper(p, &copy->cp_dst_pos);
1751 	p = xdr_decode_hyper(p, &copy->cp_count);
1752 	p++; /* ca_consecutive: we always do consecutive copies */
1753 	copy->cp_synchronous = be32_to_cpup(p++);
1754 	tmp = be32_to_cpup(p); /* Source server list not supported */
1755 
1756 	DECODE_TAIL;
1757 }
1758 
1759 static __be32
1760 nfsd4_decode_offload_status(struct nfsd4_compoundargs *argp,
1761 			    struct nfsd4_offload_status *os)
1762 {
1763 	return nfsd4_decode_stateid(argp, &os->stateid);
1764 }
1765 
1766 static __be32
1767 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
1768 {
1769 	DECODE_HEAD;
1770 
1771 	status = nfsd4_decode_stateid(argp, &seek->seek_stateid);
1772 	if (status)
1773 		return status;
1774 
1775 	READ_BUF(8 + 4);
1776 	p = xdr_decode_hyper(p, &seek->seek_offset);
1777 	seek->seek_whence = be32_to_cpup(p);
1778 
1779 	DECODE_TAIL;
1780 }
1781 
1782 static __be32
1783 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1784 {
1785 	return nfs_ok;
1786 }
1787 
1788 static __be32
1789 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1790 {
1791 	return nfserr_notsupp;
1792 }
1793 
1794 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1795 
1796 static const nfsd4_dec nfsd4_dec_ops[] = {
1797 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1798 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1799 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1800 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1801 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1802 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1803 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1804 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1805 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1806 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1807 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1808 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1809 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1810 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1811 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1812 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1813 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1814 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1815 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1816 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1817 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_putpubfh,
1818 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1819 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1820 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1821 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1822 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1823 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1824 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1825 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1826 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1827 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1828 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1829 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1830 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1831 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1832 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1833 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1834 
1835 	/* new operations for NFSv4.1 */
1836 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_backchannel_ctl,
1837 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1838 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1839 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1840 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1841 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
1842 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1843 #ifdef CONFIG_NFSD_PNFS
1844 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_getdeviceinfo,
1845 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1846 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_layoutcommit,
1847 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_layoutget,
1848 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_layoutreturn,
1849 #else
1850 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1851 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1852 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1853 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1854 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1855 #endif
1856 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1857 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1858 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1859 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
1860 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1861 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
1862 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1863 
1864 	/* new operations for NFSv4.2 */
1865 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1866 	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_copy,
1867 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
1868 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1869 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1870 	[OP_LAYOUTERROR]	= (nfsd4_dec)nfsd4_decode_notsupp,
1871 	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1872 	[OP_OFFLOAD_CANCEL]	= (nfsd4_dec)nfsd4_decode_offload_status,
1873 	[OP_OFFLOAD_STATUS]	= (nfsd4_dec)nfsd4_decode_offload_status,
1874 	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_notsupp,
1875 	[OP_SEEK]		= (nfsd4_dec)nfsd4_decode_seek,
1876 	[OP_WRITE_SAME]		= (nfsd4_dec)nfsd4_decode_notsupp,
1877 	[OP_CLONE]		= (nfsd4_dec)nfsd4_decode_clone,
1878 };
1879 
1880 static inline bool
1881 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
1882 {
1883 	if (op->opnum < FIRST_NFS4_OP)
1884 		return false;
1885 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
1886 		return false;
1887 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
1888 		return false;
1889 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
1890 		return false;
1891 	return true;
1892 }
1893 
1894 static __be32
1895 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1896 {
1897 	DECODE_HEAD;
1898 	struct nfsd4_op *op;
1899 	bool cachethis = false;
1900 	int auth_slack= argp->rqstp->rq_auth_slack;
1901 	int max_reply = auth_slack + 8; /* opcnt, status */
1902 	int readcount = 0;
1903 	int readbytes = 0;
1904 	int i;
1905 
1906 	READ_BUF(4);
1907 	argp->taglen = be32_to_cpup(p++);
1908 	READ_BUF(argp->taglen);
1909 	SAVEMEM(argp->tag, argp->taglen);
1910 	READ_BUF(8);
1911 	argp->minorversion = be32_to_cpup(p++);
1912 	argp->opcnt = be32_to_cpup(p++);
1913 	max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
1914 
1915 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1916 		goto xdr_error;
1917 	/*
1918 	 * NFS4ERR_RESOURCE is a more helpful error than GARBAGE_ARGS
1919 	 * here, so we return success at the xdr level so that
1920 	 * nfsd4_proc can handle this is an NFS-level error.
1921 	 */
1922 	if (argp->opcnt > NFSD_MAX_OPS_PER_COMPOUND)
1923 		return 0;
1924 
1925 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1926 		argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1927 		if (!argp->ops) {
1928 			argp->ops = argp->iops;
1929 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1930 			goto xdr_error;
1931 		}
1932 	}
1933 
1934 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
1935 		argp->opcnt = 0;
1936 
1937 	for (i = 0; i < argp->opcnt; i++) {
1938 		op = &argp->ops[i];
1939 		op->replay = NULL;
1940 
1941 		READ_BUF(4);
1942 		op->opnum = be32_to_cpup(p++);
1943 
1944 		if (nfsd4_opnum_in_range(argp, op))
1945 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
1946 		else {
1947 			op->opnum = OP_ILLEGAL;
1948 			op->status = nfserr_op_illegal;
1949 		}
1950 		op->opdesc = OPDESC(op);
1951 		/*
1952 		 * We'll try to cache the result in the DRC if any one
1953 		 * op in the compound wants to be cached:
1954 		 */
1955 		cachethis |= nfsd4_cache_this_op(op);
1956 
1957 		if (op->opnum == OP_READ) {
1958 			readcount++;
1959 			readbytes += nfsd4_max_reply(argp->rqstp, op);
1960 		} else
1961 			max_reply += nfsd4_max_reply(argp->rqstp, op);
1962 		/*
1963 		 * OP_LOCK and OP_LOCKT may return a conflicting lock.
1964 		 * (Special case because it will just skip encoding this
1965 		 * if it runs out of xdr buffer space, and it is the only
1966 		 * operation that behaves this way.)
1967 		 */
1968 		if (op->opnum == OP_LOCK || op->opnum == OP_LOCKT)
1969 			max_reply += NFS4_OPAQUE_LIMIT;
1970 
1971 		if (op->status) {
1972 			argp->opcnt = i+1;
1973 			break;
1974 		}
1975 	}
1976 	/* Sessions make the DRC unnecessary: */
1977 	if (argp->minorversion)
1978 		cachethis = false;
1979 	svc_reserve(argp->rqstp, max_reply + readbytes);
1980 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1981 
1982 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
1983 		clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
1984 
1985 	DECODE_TAIL;
1986 }
1987 
1988 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode,
1989 			     struct svc_export *exp)
1990 {
1991 	if (exp->ex_flags & NFSEXP_V4ROOT) {
1992 		*p++ = cpu_to_be32(convert_to_wallclock(exp->cd->flush_time));
1993 		*p++ = 0;
1994 	} else if (IS_I_VERSION(inode)) {
1995 		p = xdr_encode_hyper(p, nfsd4_change_attribute(stat, inode));
1996 	} else {
1997 		*p++ = cpu_to_be32(stat->ctime.tv_sec);
1998 		*p++ = cpu_to_be32(stat->ctime.tv_nsec);
1999 	}
2000 	return p;
2001 }
2002 
2003 /*
2004  * ctime (in NFSv4, time_metadata) is not writeable, and the client
2005  * doesn't really care what resolution could theoretically be stored by
2006  * the filesystem.
2007  *
2008  * The client cares how close together changes can be while still
2009  * guaranteeing ctime changes.  For most filesystems (which have
2010  * timestamps with nanosecond fields) that is limited by the resolution
2011  * of the time returned from current_time() (which I'm assuming to be
2012  * 1/HZ).
2013  */
2014 static __be32 *encode_time_delta(__be32 *p, struct inode *inode)
2015 {
2016 	struct timespec ts;
2017 	u32 ns;
2018 
2019 	ns = max_t(u32, NSEC_PER_SEC/HZ, inode->i_sb->s_time_gran);
2020 	ts = ns_to_timespec(ns);
2021 
2022 	p = xdr_encode_hyper(p, ts.tv_sec);
2023 	*p++ = cpu_to_be32(ts.tv_nsec);
2024 
2025 	return p;
2026 }
2027 
2028 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
2029 {
2030 	*p++ = cpu_to_be32(c->atomic);
2031 	if (c->change_supported) {
2032 		p = xdr_encode_hyper(p, c->before_change);
2033 		p = xdr_encode_hyper(p, c->after_change);
2034 	} else {
2035 		*p++ = cpu_to_be32(c->before_ctime_sec);
2036 		*p++ = cpu_to_be32(c->before_ctime_nsec);
2037 		*p++ = cpu_to_be32(c->after_ctime_sec);
2038 		*p++ = cpu_to_be32(c->after_ctime_nsec);
2039 	}
2040 	return p;
2041 }
2042 
2043 /* Encode as an array of strings the string given with components
2044  * separated @sep, escaped with esc_enter and esc_exit.
2045  */
2046 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
2047 					  char *components, char esc_enter,
2048 					  char esc_exit)
2049 {
2050 	__be32 *p;
2051 	__be32 pathlen;
2052 	int pathlen_offset;
2053 	int strlen, count=0;
2054 	char *str, *end, *next;
2055 
2056 	dprintk("nfsd4_encode_components(%s)\n", components);
2057 
2058 	pathlen_offset = xdr->buf->len;
2059 	p = xdr_reserve_space(xdr, 4);
2060 	if (!p)
2061 		return nfserr_resource;
2062 	p++; /* We will fill this in with @count later */
2063 
2064 	end = str = components;
2065 	while (*end) {
2066 		bool found_esc = false;
2067 
2068 		/* try to parse as esc_start, ..., esc_end, sep */
2069 		if (*str == esc_enter) {
2070 			for (; *end && (*end != esc_exit); end++)
2071 				/* find esc_exit or end of string */;
2072 			next = end + 1;
2073 			if (*end && (!*next || *next == sep)) {
2074 				str++;
2075 				found_esc = true;
2076 			}
2077 		}
2078 
2079 		if (!found_esc)
2080 			for (; *end && (*end != sep); end++)
2081 				/* find sep or end of string */;
2082 
2083 		strlen = end - str;
2084 		if (strlen) {
2085 			p = xdr_reserve_space(xdr, strlen + 4);
2086 			if (!p)
2087 				return nfserr_resource;
2088 			p = xdr_encode_opaque(p, str, strlen);
2089 			count++;
2090 		}
2091 		else
2092 			end++;
2093 		if (found_esc)
2094 			end = next;
2095 
2096 		str = end;
2097 	}
2098 	pathlen = htonl(count);
2099 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
2100 	return 0;
2101 }
2102 
2103 /* Encode as an array of strings the string given with components
2104  * separated @sep.
2105  */
2106 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
2107 				      char *components)
2108 {
2109 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
2110 }
2111 
2112 /*
2113  * encode a location element of a fs_locations structure
2114  */
2115 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
2116 					struct nfsd4_fs_location *location)
2117 {
2118 	__be32 status;
2119 
2120 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
2121 						'[', ']');
2122 	if (status)
2123 		return status;
2124 	status = nfsd4_encode_components(xdr, '/', location->path);
2125 	if (status)
2126 		return status;
2127 	return 0;
2128 }
2129 
2130 /*
2131  * Encode a path in RFC3530 'pathname4' format
2132  */
2133 static __be32 nfsd4_encode_path(struct xdr_stream *xdr,
2134 				const struct path *root,
2135 				const struct path *path)
2136 {
2137 	struct path cur = *path;
2138 	__be32 *p;
2139 	struct dentry **components = NULL;
2140 	unsigned int ncomponents = 0;
2141 	__be32 err = nfserr_jukebox;
2142 
2143 	dprintk("nfsd4_encode_components(");
2144 
2145 	path_get(&cur);
2146 	/* First walk the path up to the nfsd root, and store the
2147 	 * dentries/path components in an array.
2148 	 */
2149 	for (;;) {
2150 		if (path_equal(&cur, root))
2151 			break;
2152 		if (cur.dentry == cur.mnt->mnt_root) {
2153 			if (follow_up(&cur))
2154 				continue;
2155 			goto out_free;
2156 		}
2157 		if ((ncomponents & 15) == 0) {
2158 			struct dentry **new;
2159 			new = krealloc(components,
2160 					sizeof(*new) * (ncomponents + 16),
2161 					GFP_KERNEL);
2162 			if (!new)
2163 				goto out_free;
2164 			components = new;
2165 		}
2166 		components[ncomponents++] = cur.dentry;
2167 		cur.dentry = dget_parent(cur.dentry);
2168 	}
2169 	err = nfserr_resource;
2170 	p = xdr_reserve_space(xdr, 4);
2171 	if (!p)
2172 		goto out_free;
2173 	*p++ = cpu_to_be32(ncomponents);
2174 
2175 	while (ncomponents) {
2176 		struct dentry *dentry = components[ncomponents - 1];
2177 		unsigned int len;
2178 
2179 		spin_lock(&dentry->d_lock);
2180 		len = dentry->d_name.len;
2181 		p = xdr_reserve_space(xdr, len + 4);
2182 		if (!p) {
2183 			spin_unlock(&dentry->d_lock);
2184 			goto out_free;
2185 		}
2186 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
2187 		dprintk("/%pd", dentry);
2188 		spin_unlock(&dentry->d_lock);
2189 		dput(dentry);
2190 		ncomponents--;
2191 	}
2192 
2193 	err = 0;
2194 out_free:
2195 	dprintk(")\n");
2196 	while (ncomponents)
2197 		dput(components[--ncomponents]);
2198 	kfree(components);
2199 	path_put(&cur);
2200 	return err;
2201 }
2202 
2203 static __be32 nfsd4_encode_fsloc_fsroot(struct xdr_stream *xdr,
2204 			struct svc_rqst *rqstp, const struct path *path)
2205 {
2206 	struct svc_export *exp_ps;
2207 	__be32 res;
2208 
2209 	exp_ps = rqst_find_fsidzero_export(rqstp);
2210 	if (IS_ERR(exp_ps))
2211 		return nfserrno(PTR_ERR(exp_ps));
2212 	res = nfsd4_encode_path(xdr, &exp_ps->ex_path, path);
2213 	exp_put(exp_ps);
2214 	return res;
2215 }
2216 
2217 /*
2218  *  encode a fs_locations structure
2219  */
2220 static __be32 nfsd4_encode_fs_locations(struct xdr_stream *xdr,
2221 			struct svc_rqst *rqstp, struct svc_export *exp)
2222 {
2223 	__be32 status;
2224 	int i;
2225 	__be32 *p;
2226 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
2227 
2228 	status = nfsd4_encode_fsloc_fsroot(xdr, rqstp, &exp->ex_path);
2229 	if (status)
2230 		return status;
2231 	p = xdr_reserve_space(xdr, 4);
2232 	if (!p)
2233 		return nfserr_resource;
2234 	*p++ = cpu_to_be32(fslocs->locations_count);
2235 	for (i=0; i<fslocs->locations_count; i++) {
2236 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
2237 		if (status)
2238 			return status;
2239 	}
2240 	return 0;
2241 }
2242 
2243 static u32 nfs4_file_type(umode_t mode)
2244 {
2245 	switch (mode & S_IFMT) {
2246 	case S_IFIFO:	return NF4FIFO;
2247 	case S_IFCHR:	return NF4CHR;
2248 	case S_IFDIR:	return NF4DIR;
2249 	case S_IFBLK:	return NF4BLK;
2250 	case S_IFLNK:	return NF4LNK;
2251 	case S_IFREG:	return NF4REG;
2252 	case S_IFSOCK:	return NF4SOCK;
2253 	default:	return NF4BAD;
2254 	};
2255 }
2256 
2257 static inline __be32
2258 nfsd4_encode_aclname(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2259 		     struct nfs4_ace *ace)
2260 {
2261 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
2262 		return nfs4_acl_write_who(xdr, ace->whotype);
2263 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
2264 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
2265 	else
2266 		return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
2267 }
2268 
2269 static inline __be32
2270 nfsd4_encode_layout_types(struct xdr_stream *xdr, u32 layout_types)
2271 {
2272 	__be32		*p;
2273 	unsigned long	i = hweight_long(layout_types);
2274 
2275 	p = xdr_reserve_space(xdr, 4 + 4 * i);
2276 	if (!p)
2277 		return nfserr_resource;
2278 
2279 	*p++ = cpu_to_be32(i);
2280 
2281 	for (i = LAYOUT_NFSV4_1_FILES; i < LAYOUT_TYPE_MAX; ++i)
2282 		if (layout_types & (1 << i))
2283 			*p++ = cpu_to_be32(i);
2284 
2285 	return 0;
2286 }
2287 
2288 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
2289 			      FATTR4_WORD0_RDATTR_ERROR)
2290 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2291 #define WORD2_ABSENT_FS_ATTRS 0
2292 
2293 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2294 static inline __be32
2295 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2296 			    void *context, int len)
2297 {
2298 	__be32 *p;
2299 
2300 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2301 	if (!p)
2302 		return nfserr_resource;
2303 
2304 	/*
2305 	 * For now we use a 0 here to indicate the null translation; in
2306 	 * the future we may place a call to translation code here.
2307 	 */
2308 	*p++ = cpu_to_be32(0); /* lfs */
2309 	*p++ = cpu_to_be32(0); /* pi */
2310 	p = xdr_encode_opaque(p, context, len);
2311 	return 0;
2312 }
2313 #else
2314 static inline __be32
2315 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2316 			    void *context, int len)
2317 { return 0; }
2318 #endif
2319 
2320 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *bmval2, u32 *rdattr_err)
2321 {
2322 	/* As per referral draft:  */
2323 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2324 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2325 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2326 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2327 			*rdattr_err = NFSERR_MOVED;
2328 		else
2329 			return nfserr_moved;
2330 	}
2331 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2332 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2333 	*bmval2 &= WORD2_ABSENT_FS_ATTRS;
2334 	return 0;
2335 }
2336 
2337 
2338 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2339 {
2340 	struct path path = exp->ex_path;
2341 	int err;
2342 
2343 	path_get(&path);
2344 	while (follow_up(&path)) {
2345 		if (path.dentry != path.mnt->mnt_root)
2346 			break;
2347 	}
2348 	err = vfs_getattr(&path, stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
2349 	path_put(&path);
2350 	return err;
2351 }
2352 
2353 static __be32
2354 nfsd4_encode_bitmap(struct xdr_stream *xdr, u32 bmval0, u32 bmval1, u32 bmval2)
2355 {
2356 	__be32 *p;
2357 
2358 	if (bmval2) {
2359 		p = xdr_reserve_space(xdr, 16);
2360 		if (!p)
2361 			goto out_resource;
2362 		*p++ = cpu_to_be32(3);
2363 		*p++ = cpu_to_be32(bmval0);
2364 		*p++ = cpu_to_be32(bmval1);
2365 		*p++ = cpu_to_be32(bmval2);
2366 	} else if (bmval1) {
2367 		p = xdr_reserve_space(xdr, 12);
2368 		if (!p)
2369 			goto out_resource;
2370 		*p++ = cpu_to_be32(2);
2371 		*p++ = cpu_to_be32(bmval0);
2372 		*p++ = cpu_to_be32(bmval1);
2373 	} else {
2374 		p = xdr_reserve_space(xdr, 8);
2375 		if (!p)
2376 			goto out_resource;
2377 		*p++ = cpu_to_be32(1);
2378 		*p++ = cpu_to_be32(bmval0);
2379 	}
2380 
2381 	return 0;
2382 out_resource:
2383 	return nfserr_resource;
2384 }
2385 
2386 /*
2387  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2388  * ourselves.
2389  */
2390 static __be32
2391 nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
2392 		struct svc_export *exp,
2393 		struct dentry *dentry, u32 *bmval,
2394 		struct svc_rqst *rqstp, int ignore_crossmnt)
2395 {
2396 	u32 bmval0 = bmval[0];
2397 	u32 bmval1 = bmval[1];
2398 	u32 bmval2 = bmval[2];
2399 	struct kstat stat;
2400 	struct svc_fh *tempfh = NULL;
2401 	struct kstatfs statfs;
2402 	__be32 *p;
2403 	int starting_len = xdr->buf->len;
2404 	int attrlen_offset;
2405 	__be32 attrlen;
2406 	u32 dummy;
2407 	u64 dummy64;
2408 	u32 rdattr_err = 0;
2409 	__be32 status;
2410 	int err;
2411 	struct nfs4_acl *acl = NULL;
2412 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2413 	void *context = NULL;
2414 	int contextlen;
2415 #endif
2416 	bool contextsupport = false;
2417 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2418 	u32 minorversion = resp->cstate.minorversion;
2419 	struct path path = {
2420 		.mnt	= exp->ex_path.mnt,
2421 		.dentry	= dentry,
2422 	};
2423 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2424 
2425 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2426 	BUG_ON(!nfsd_attrs_supported(minorversion, bmval));
2427 
2428 	if (exp->ex_fslocs.migrated) {
2429 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &bmval2, &rdattr_err);
2430 		if (status)
2431 			goto out;
2432 	}
2433 
2434 	err = vfs_getattr(&path, &stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
2435 	if (err)
2436 		goto out_nfserr;
2437 	if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
2438 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
2439 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2440 		       FATTR4_WORD1_SPACE_TOTAL))) {
2441 		err = vfs_statfs(&path, &statfs);
2442 		if (err)
2443 			goto out_nfserr;
2444 	}
2445 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2446 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2447 		status = nfserr_jukebox;
2448 		if (!tempfh)
2449 			goto out;
2450 		fh_init(tempfh, NFS4_FHSIZE);
2451 		status = fh_compose(tempfh, exp, dentry, NULL);
2452 		if (status)
2453 			goto out;
2454 		fhp = tempfh;
2455 	}
2456 	if (bmval0 & FATTR4_WORD0_ACL) {
2457 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2458 		if (err == -EOPNOTSUPP)
2459 			bmval0 &= ~FATTR4_WORD0_ACL;
2460 		else if (err == -EINVAL) {
2461 			status = nfserr_attrnotsupp;
2462 			goto out;
2463 		} else if (err != 0)
2464 			goto out_nfserr;
2465 	}
2466 
2467 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2468 	if ((bmval2 & FATTR4_WORD2_SECURITY_LABEL) ||
2469 	     bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2470 		if (exp->ex_flags & NFSEXP_SECURITY_LABEL)
2471 			err = security_inode_getsecctx(d_inode(dentry),
2472 						&context, &contextlen);
2473 		else
2474 			err = -EOPNOTSUPP;
2475 		contextsupport = (err == 0);
2476 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2477 			if (err == -EOPNOTSUPP)
2478 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2479 			else if (err)
2480 				goto out_nfserr;
2481 		}
2482 	}
2483 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2484 
2485 	status = nfsd4_encode_bitmap(xdr, bmval0, bmval1, bmval2);
2486 	if (status)
2487 		goto out;
2488 
2489 	attrlen_offset = xdr->buf->len;
2490 	p = xdr_reserve_space(xdr, 4);
2491 	if (!p)
2492 		goto out_resource;
2493 	p++;                /* to be backfilled later */
2494 
2495 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2496 		u32 supp[3];
2497 
2498 		memcpy(supp, nfsd_suppattrs[minorversion], sizeof(supp));
2499 
2500 		if (!IS_POSIXACL(dentry->d_inode))
2501 			supp[0] &= ~FATTR4_WORD0_ACL;
2502 		if (!contextsupport)
2503 			supp[2] &= ~FATTR4_WORD2_SECURITY_LABEL;
2504 		if (!supp[2]) {
2505 			p = xdr_reserve_space(xdr, 12);
2506 			if (!p)
2507 				goto out_resource;
2508 			*p++ = cpu_to_be32(2);
2509 			*p++ = cpu_to_be32(supp[0]);
2510 			*p++ = cpu_to_be32(supp[1]);
2511 		} else {
2512 			p = xdr_reserve_space(xdr, 16);
2513 			if (!p)
2514 				goto out_resource;
2515 			*p++ = cpu_to_be32(3);
2516 			*p++ = cpu_to_be32(supp[0]);
2517 			*p++ = cpu_to_be32(supp[1]);
2518 			*p++ = cpu_to_be32(supp[2]);
2519 		}
2520 	}
2521 	if (bmval0 & FATTR4_WORD0_TYPE) {
2522 		p = xdr_reserve_space(xdr, 4);
2523 		if (!p)
2524 			goto out_resource;
2525 		dummy = nfs4_file_type(stat.mode);
2526 		if (dummy == NF4BAD) {
2527 			status = nfserr_serverfault;
2528 			goto out;
2529 		}
2530 		*p++ = cpu_to_be32(dummy);
2531 	}
2532 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2533 		p = xdr_reserve_space(xdr, 4);
2534 		if (!p)
2535 			goto out_resource;
2536 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2537 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT);
2538 		else
2539 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT|
2540 						NFS4_FH_VOL_RENAME);
2541 	}
2542 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2543 		p = xdr_reserve_space(xdr, 8);
2544 		if (!p)
2545 			goto out_resource;
2546 		p = encode_change(p, &stat, d_inode(dentry), exp);
2547 	}
2548 	if (bmval0 & FATTR4_WORD0_SIZE) {
2549 		p = xdr_reserve_space(xdr, 8);
2550 		if (!p)
2551 			goto out_resource;
2552 		p = xdr_encode_hyper(p, stat.size);
2553 	}
2554 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2555 		p = xdr_reserve_space(xdr, 4);
2556 		if (!p)
2557 			goto out_resource;
2558 		*p++ = cpu_to_be32(1);
2559 	}
2560 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2561 		p = xdr_reserve_space(xdr, 4);
2562 		if (!p)
2563 			goto out_resource;
2564 		*p++ = cpu_to_be32(1);
2565 	}
2566 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2567 		p = xdr_reserve_space(xdr, 4);
2568 		if (!p)
2569 			goto out_resource;
2570 		*p++ = cpu_to_be32(0);
2571 	}
2572 	if (bmval0 & FATTR4_WORD0_FSID) {
2573 		p = xdr_reserve_space(xdr, 16);
2574 		if (!p)
2575 			goto out_resource;
2576 		if (exp->ex_fslocs.migrated) {
2577 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
2578 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
2579 		} else switch(fsid_source(fhp)) {
2580 		case FSIDSOURCE_FSID:
2581 			p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
2582 			p = xdr_encode_hyper(p, (u64)0);
2583 			break;
2584 		case FSIDSOURCE_DEV:
2585 			*p++ = cpu_to_be32(0);
2586 			*p++ = cpu_to_be32(MAJOR(stat.dev));
2587 			*p++ = cpu_to_be32(0);
2588 			*p++ = cpu_to_be32(MINOR(stat.dev));
2589 			break;
2590 		case FSIDSOURCE_UUID:
2591 			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
2592 								EX_UUID_LEN);
2593 			break;
2594 		}
2595 	}
2596 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2597 		p = xdr_reserve_space(xdr, 4);
2598 		if (!p)
2599 			goto out_resource;
2600 		*p++ = cpu_to_be32(0);
2601 	}
2602 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2603 		p = xdr_reserve_space(xdr, 4);
2604 		if (!p)
2605 			goto out_resource;
2606 		*p++ = cpu_to_be32(nn->nfsd4_lease);
2607 	}
2608 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2609 		p = xdr_reserve_space(xdr, 4);
2610 		if (!p)
2611 			goto out_resource;
2612 		*p++ = cpu_to_be32(rdattr_err);
2613 	}
2614 	if (bmval0 & FATTR4_WORD0_ACL) {
2615 		struct nfs4_ace *ace;
2616 
2617 		if (acl == NULL) {
2618 			p = xdr_reserve_space(xdr, 4);
2619 			if (!p)
2620 				goto out_resource;
2621 
2622 			*p++ = cpu_to_be32(0);
2623 			goto out_acl;
2624 		}
2625 		p = xdr_reserve_space(xdr, 4);
2626 		if (!p)
2627 			goto out_resource;
2628 		*p++ = cpu_to_be32(acl->naces);
2629 
2630 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2631 			p = xdr_reserve_space(xdr, 4*3);
2632 			if (!p)
2633 				goto out_resource;
2634 			*p++ = cpu_to_be32(ace->type);
2635 			*p++ = cpu_to_be32(ace->flag);
2636 			*p++ = cpu_to_be32(ace->access_mask &
2637 							NFS4_ACE_MASK_ALL);
2638 			status = nfsd4_encode_aclname(xdr, rqstp, ace);
2639 			if (status)
2640 				goto out;
2641 		}
2642 	}
2643 out_acl:
2644 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2645 		p = xdr_reserve_space(xdr, 4);
2646 		if (!p)
2647 			goto out_resource;
2648 		*p++ = cpu_to_be32(IS_POSIXACL(dentry->d_inode) ?
2649 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2650 	}
2651 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2652 		p = xdr_reserve_space(xdr, 4);
2653 		if (!p)
2654 			goto out_resource;
2655 		*p++ = cpu_to_be32(1);
2656 	}
2657 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2658 		p = xdr_reserve_space(xdr, 4);
2659 		if (!p)
2660 			goto out_resource;
2661 		*p++ = cpu_to_be32(0);
2662 	}
2663 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2664 		p = xdr_reserve_space(xdr, 4);
2665 		if (!p)
2666 			goto out_resource;
2667 		*p++ = cpu_to_be32(1);
2668 	}
2669 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2670 		p = xdr_reserve_space(xdr, 4);
2671 		if (!p)
2672 			goto out_resource;
2673 		*p++ = cpu_to_be32(1);
2674 	}
2675 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2676 		p = xdr_reserve_space(xdr, fhp->fh_handle.fh_size + 4);
2677 		if (!p)
2678 			goto out_resource;
2679 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base,
2680 					fhp->fh_handle.fh_size);
2681 	}
2682 	if (bmval0 & FATTR4_WORD0_FILEID) {
2683 		p = xdr_reserve_space(xdr, 8);
2684 		if (!p)
2685 			goto out_resource;
2686 		p = xdr_encode_hyper(p, stat.ino);
2687 	}
2688 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2689 		p = xdr_reserve_space(xdr, 8);
2690 		if (!p)
2691 			goto out_resource;
2692 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2693 	}
2694 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2695 		p = xdr_reserve_space(xdr, 8);
2696 		if (!p)
2697 			goto out_resource;
2698 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2699 	}
2700 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2701 		p = xdr_reserve_space(xdr, 8);
2702 		if (!p)
2703 			goto out_resource;
2704 		p = xdr_encode_hyper(p, (u64) statfs.f_files);
2705 	}
2706 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2707 		status = nfsd4_encode_fs_locations(xdr, rqstp, exp);
2708 		if (status)
2709 			goto out;
2710 	}
2711 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2712 		p = xdr_reserve_space(xdr, 4);
2713 		if (!p)
2714 			goto out_resource;
2715 		*p++ = cpu_to_be32(1);
2716 	}
2717 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2718 		p = xdr_reserve_space(xdr, 8);
2719 		if (!p)
2720 			goto out_resource;
2721 		p = xdr_encode_hyper(p, exp->ex_path.mnt->mnt_sb->s_maxbytes);
2722 	}
2723 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2724 		p = xdr_reserve_space(xdr, 4);
2725 		if (!p)
2726 			goto out_resource;
2727 		*p++ = cpu_to_be32(255);
2728 	}
2729 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2730 		p = xdr_reserve_space(xdr, 4);
2731 		if (!p)
2732 			goto out_resource;
2733 		*p++ = cpu_to_be32(statfs.f_namelen);
2734 	}
2735 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2736 		p = xdr_reserve_space(xdr, 8);
2737 		if (!p)
2738 			goto out_resource;
2739 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2740 	}
2741 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2742 		p = xdr_reserve_space(xdr, 8);
2743 		if (!p)
2744 			goto out_resource;
2745 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2746 	}
2747 	if (bmval1 & FATTR4_WORD1_MODE) {
2748 		p = xdr_reserve_space(xdr, 4);
2749 		if (!p)
2750 			goto out_resource;
2751 		*p++ = cpu_to_be32(stat.mode & S_IALLUGO);
2752 	}
2753 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2754 		p = xdr_reserve_space(xdr, 4);
2755 		if (!p)
2756 			goto out_resource;
2757 		*p++ = cpu_to_be32(1);
2758 	}
2759 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2760 		p = xdr_reserve_space(xdr, 4);
2761 		if (!p)
2762 			goto out_resource;
2763 		*p++ = cpu_to_be32(stat.nlink);
2764 	}
2765 	if (bmval1 & FATTR4_WORD1_OWNER) {
2766 		status = nfsd4_encode_user(xdr, rqstp, stat.uid);
2767 		if (status)
2768 			goto out;
2769 	}
2770 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2771 		status = nfsd4_encode_group(xdr, rqstp, stat.gid);
2772 		if (status)
2773 			goto out;
2774 	}
2775 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2776 		p = xdr_reserve_space(xdr, 8);
2777 		if (!p)
2778 			goto out_resource;
2779 		*p++ = cpu_to_be32((u32) MAJOR(stat.rdev));
2780 		*p++ = cpu_to_be32((u32) MINOR(stat.rdev));
2781 	}
2782 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2783 		p = xdr_reserve_space(xdr, 8);
2784 		if (!p)
2785 			goto out_resource;
2786 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2787 		p = xdr_encode_hyper(p, dummy64);
2788 	}
2789 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2790 		p = xdr_reserve_space(xdr, 8);
2791 		if (!p)
2792 			goto out_resource;
2793 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2794 		p = xdr_encode_hyper(p, dummy64);
2795 	}
2796 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2797 		p = xdr_reserve_space(xdr, 8);
2798 		if (!p)
2799 			goto out_resource;
2800 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2801 		p = xdr_encode_hyper(p, dummy64);
2802 	}
2803 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2804 		p = xdr_reserve_space(xdr, 8);
2805 		if (!p)
2806 			goto out_resource;
2807 		dummy64 = (u64)stat.blocks << 9;
2808 		p = xdr_encode_hyper(p, dummy64);
2809 	}
2810 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2811 		p = xdr_reserve_space(xdr, 12);
2812 		if (!p)
2813 			goto out_resource;
2814 		p = xdr_encode_hyper(p, (s64)stat.atime.tv_sec);
2815 		*p++ = cpu_to_be32(stat.atime.tv_nsec);
2816 	}
2817 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2818 		p = xdr_reserve_space(xdr, 12);
2819 		if (!p)
2820 			goto out_resource;
2821 		p = encode_time_delta(p, d_inode(dentry));
2822 	}
2823 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2824 		p = xdr_reserve_space(xdr, 12);
2825 		if (!p)
2826 			goto out_resource;
2827 		p = xdr_encode_hyper(p, (s64)stat.ctime.tv_sec);
2828 		*p++ = cpu_to_be32(stat.ctime.tv_nsec);
2829 	}
2830 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2831 		p = xdr_reserve_space(xdr, 12);
2832 		if (!p)
2833 			goto out_resource;
2834 		p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
2835 		*p++ = cpu_to_be32(stat.mtime.tv_nsec);
2836 	}
2837 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2838 		struct kstat parent_stat;
2839 		u64 ino = stat.ino;
2840 
2841 		p = xdr_reserve_space(xdr, 8);
2842 		if (!p)
2843                 	goto out_resource;
2844 		/*
2845 		 * Get parent's attributes if not ignoring crossmount
2846 		 * and this is the root of a cross-mounted filesystem.
2847 		 */
2848 		if (ignore_crossmnt == 0 &&
2849 		    dentry == exp->ex_path.mnt->mnt_root) {
2850 			err = get_parent_attributes(exp, &parent_stat);
2851 			if (err)
2852 				goto out_nfserr;
2853 			ino = parent_stat.ino;
2854 		}
2855 		p = xdr_encode_hyper(p, ino);
2856 	}
2857 #ifdef CONFIG_NFSD_PNFS
2858 	if (bmval1 & FATTR4_WORD1_FS_LAYOUT_TYPES) {
2859 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
2860 		if (status)
2861 			goto out;
2862 	}
2863 
2864 	if (bmval2 & FATTR4_WORD2_LAYOUT_TYPES) {
2865 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
2866 		if (status)
2867 			goto out;
2868 	}
2869 
2870 	if (bmval2 & FATTR4_WORD2_LAYOUT_BLKSIZE) {
2871 		p = xdr_reserve_space(xdr, 4);
2872 		if (!p)
2873 			goto out_resource;
2874 		*p++ = cpu_to_be32(stat.blksize);
2875 	}
2876 #endif /* CONFIG_NFSD_PNFS */
2877 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2878 		u32 supp[3];
2879 
2880 		memcpy(supp, nfsd_suppattrs[minorversion], sizeof(supp));
2881 		supp[0] &= NFSD_SUPPATTR_EXCLCREAT_WORD0;
2882 		supp[1] &= NFSD_SUPPATTR_EXCLCREAT_WORD1;
2883 		supp[2] &= NFSD_SUPPATTR_EXCLCREAT_WORD2;
2884 
2885 		status = nfsd4_encode_bitmap(xdr, supp[0], supp[1], supp[2]);
2886 		if (status)
2887 			goto out;
2888 	}
2889 
2890 	if (bmval2 & FATTR4_WORD2_CHANGE_ATTR_TYPE) {
2891 		p = xdr_reserve_space(xdr, 4);
2892 		if (!p)
2893 			goto out_resource;
2894 		if (IS_I_VERSION(d_inode(dentry)))
2895 			*p++ = cpu_to_be32(NFS4_CHANGE_TYPE_IS_MONOTONIC_INCR);
2896 		else
2897 			*p++ = cpu_to_be32(NFS4_CHANGE_TYPE_IS_TIME_METADATA);
2898 	}
2899 
2900 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2901 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2902 		status = nfsd4_encode_security_label(xdr, rqstp, context,
2903 								contextlen);
2904 		if (status)
2905 			goto out;
2906 	}
2907 #endif
2908 
2909 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
2910 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
2911 	status = nfs_ok;
2912 
2913 out:
2914 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2915 	if (context)
2916 		security_release_secctx(context, contextlen);
2917 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2918 	kfree(acl);
2919 	if (tempfh) {
2920 		fh_put(tempfh);
2921 		kfree(tempfh);
2922 	}
2923 	if (status)
2924 		xdr_truncate_encode(xdr, starting_len);
2925 	return status;
2926 out_nfserr:
2927 	status = nfserrno(err);
2928 	goto out;
2929 out_resource:
2930 	status = nfserr_resource;
2931 	goto out;
2932 }
2933 
2934 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
2935 				struct xdr_buf *buf, __be32 *p, int bytes)
2936 {
2937 	xdr->scratch.iov_len = 0;
2938 	memset(buf, 0, sizeof(struct xdr_buf));
2939 	buf->head[0].iov_base = p;
2940 	buf->head[0].iov_len = 0;
2941 	buf->len = 0;
2942 	xdr->buf = buf;
2943 	xdr->iov = buf->head;
2944 	xdr->p = p;
2945 	xdr->end = (void *)p + bytes;
2946 	buf->buflen = bytes;
2947 }
2948 
2949 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
2950 			struct svc_fh *fhp, struct svc_export *exp,
2951 			struct dentry *dentry, u32 *bmval,
2952 			struct svc_rqst *rqstp, int ignore_crossmnt)
2953 {
2954 	struct xdr_buf dummy;
2955 	struct xdr_stream xdr;
2956 	__be32 ret;
2957 
2958 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
2959 	ret = nfsd4_encode_fattr(&xdr, fhp, exp, dentry, bmval, rqstp,
2960 							ignore_crossmnt);
2961 	*p = xdr.p;
2962 	return ret;
2963 }
2964 
2965 static inline int attributes_need_mount(u32 *bmval)
2966 {
2967 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2968 		return 1;
2969 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2970 		return 1;
2971 	return 0;
2972 }
2973 
2974 static __be32
2975 nfsd4_encode_dirent_fattr(struct xdr_stream *xdr, struct nfsd4_readdir *cd,
2976 			const char *name, int namlen)
2977 {
2978 	struct svc_export *exp = cd->rd_fhp->fh_export;
2979 	struct dentry *dentry;
2980 	__be32 nfserr;
2981 	int ignore_crossmnt = 0;
2982 
2983 	dentry = lookup_one_len_unlocked(name, cd->rd_fhp->fh_dentry, namlen);
2984 	if (IS_ERR(dentry))
2985 		return nfserrno(PTR_ERR(dentry));
2986 	if (d_really_is_negative(dentry)) {
2987 		/*
2988 		 * we're not holding the i_mutex here, so there's
2989 		 * a window where this directory entry could have gone
2990 		 * away.
2991 		 */
2992 		dput(dentry);
2993 		return nfserr_noent;
2994 	}
2995 
2996 	exp_get(exp);
2997 	/*
2998 	 * In the case of a mountpoint, the client may be asking for
2999 	 * attributes that are only properties of the underlying filesystem
3000 	 * as opposed to the cross-mounted file system. In such a case,
3001 	 * we will not follow the cross mount and will fill the attribtutes
3002 	 * directly from the mountpoint dentry.
3003 	 */
3004 	if (nfsd_mountpoint(dentry, exp)) {
3005 		int err;
3006 
3007 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
3008 				&& !attributes_need_mount(cd->rd_bmval)) {
3009 			ignore_crossmnt = 1;
3010 			goto out_encode;
3011 		}
3012 		/*
3013 		 * Why the heck aren't we just using nfsd_lookup??
3014 		 * Different "."/".." handling?  Something else?
3015 		 * At least, add a comment here to explain....
3016 		 */
3017 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
3018 		if (err) {
3019 			nfserr = nfserrno(err);
3020 			goto out_put;
3021 		}
3022 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
3023 		if (nfserr)
3024 			goto out_put;
3025 
3026 	}
3027 out_encode:
3028 	nfserr = nfsd4_encode_fattr(xdr, NULL, exp, dentry, cd->rd_bmval,
3029 					cd->rd_rqstp, ignore_crossmnt);
3030 out_put:
3031 	dput(dentry);
3032 	exp_put(exp);
3033 	return nfserr;
3034 }
3035 
3036 static __be32 *
3037 nfsd4_encode_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
3038 {
3039 	__be32 *p;
3040 
3041 	p = xdr_reserve_space(xdr, 20);
3042 	if (!p)
3043 		return NULL;
3044 	*p++ = htonl(2);
3045 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
3046 	*p++ = htonl(0);			 /* bmval1 */
3047 
3048 	*p++ = htonl(4);     /* attribute length */
3049 	*p++ = nfserr;       /* no htonl */
3050 	return p;
3051 }
3052 
3053 static int
3054 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
3055 		    loff_t offset, u64 ino, unsigned int d_type)
3056 {
3057 	struct readdir_cd *ccd = ccdv;
3058 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
3059 	struct xdr_stream *xdr = cd->xdr;
3060 	int start_offset = xdr->buf->len;
3061 	int cookie_offset;
3062 	u32 name_and_cookie;
3063 	int entry_bytes;
3064 	__be32 nfserr = nfserr_toosmall;
3065 	__be64 wire_offset;
3066 	__be32 *p;
3067 
3068 	/* In nfsv4, "." and ".." never make it onto the wire.. */
3069 	if (name && isdotent(name, namlen)) {
3070 		cd->common.err = nfs_ok;
3071 		return 0;
3072 	}
3073 
3074 	if (cd->cookie_offset) {
3075 		wire_offset = cpu_to_be64(offset);
3076 		write_bytes_to_xdr_buf(xdr->buf, cd->cookie_offset,
3077 							&wire_offset, 8);
3078 	}
3079 
3080 	p = xdr_reserve_space(xdr, 4);
3081 	if (!p)
3082 		goto fail;
3083 	*p++ = xdr_one;                             /* mark entry present */
3084 	cookie_offset = xdr->buf->len;
3085 	p = xdr_reserve_space(xdr, 3*4 + namlen);
3086 	if (!p)
3087 		goto fail;
3088 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
3089 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
3090 
3091 	nfserr = nfsd4_encode_dirent_fattr(xdr, cd, name, namlen);
3092 	switch (nfserr) {
3093 	case nfs_ok:
3094 		break;
3095 	case nfserr_resource:
3096 		nfserr = nfserr_toosmall;
3097 		goto fail;
3098 	case nfserr_noent:
3099 		xdr_truncate_encode(xdr, start_offset);
3100 		goto skip_entry;
3101 	default:
3102 		/*
3103 		 * If the client requested the RDATTR_ERROR attribute,
3104 		 * we stuff the error code into this attribute
3105 		 * and continue.  If this attribute was not requested,
3106 		 * then in accordance with the spec, we fail the
3107 		 * entire READDIR operation(!)
3108 		 */
3109 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
3110 			goto fail;
3111 		p = nfsd4_encode_rdattr_error(xdr, nfserr);
3112 		if (p == NULL) {
3113 			nfserr = nfserr_toosmall;
3114 			goto fail;
3115 		}
3116 	}
3117 	nfserr = nfserr_toosmall;
3118 	entry_bytes = xdr->buf->len - start_offset;
3119 	if (entry_bytes > cd->rd_maxcount)
3120 		goto fail;
3121 	cd->rd_maxcount -= entry_bytes;
3122 	/*
3123 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so
3124 	 * let's always let through the first entry, at least:
3125 	 */
3126 	if (!cd->rd_dircount)
3127 		goto fail;
3128 	name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8;
3129 	if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
3130 		goto fail;
3131 	cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
3132 
3133 	cd->cookie_offset = cookie_offset;
3134 skip_entry:
3135 	cd->common.err = nfs_ok;
3136 	return 0;
3137 fail:
3138 	xdr_truncate_encode(xdr, start_offset);
3139 	cd->common.err = nfserr;
3140 	return -EINVAL;
3141 }
3142 
3143 static __be32
3144 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
3145 {
3146 	__be32 *p;
3147 
3148 	p = xdr_reserve_space(xdr, sizeof(stateid_t));
3149 	if (!p)
3150 		return nfserr_resource;
3151 	*p++ = cpu_to_be32(sid->si_generation);
3152 	p = xdr_encode_opaque_fixed(p, &sid->si_opaque,
3153 					sizeof(stateid_opaque_t));
3154 	return 0;
3155 }
3156 
3157 static __be32
3158 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
3159 {
3160 	struct xdr_stream *xdr = &resp->xdr;
3161 	__be32 *p;
3162 
3163 	p = xdr_reserve_space(xdr, 8);
3164 	if (!p)
3165 		return nfserr_resource;
3166 	*p++ = cpu_to_be32(access->ac_supported);
3167 	*p++ = cpu_to_be32(access->ac_resp_access);
3168 	return 0;
3169 }
3170 
3171 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
3172 {
3173 	struct xdr_stream *xdr = &resp->xdr;
3174 	__be32 *p;
3175 
3176 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 8);
3177 	if (!p)
3178 		return nfserr_resource;
3179 	p = xdr_encode_opaque_fixed(p, bcts->sessionid.data,
3180 					NFS4_MAX_SESSIONID_LEN);
3181 	*p++ = cpu_to_be32(bcts->dir);
3182 	/* Upshifting from TCP to RDMA is not supported */
3183 	*p++ = cpu_to_be32(0);
3184 	return 0;
3185 }
3186 
3187 static __be32
3188 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
3189 {
3190 	struct xdr_stream *xdr = &resp->xdr;
3191 
3192 	return nfsd4_encode_stateid(xdr, &close->cl_stateid);
3193 }
3194 
3195 
3196 static __be32
3197 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
3198 {
3199 	struct xdr_stream *xdr = &resp->xdr;
3200 	__be32 *p;
3201 
3202 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3203 	if (!p)
3204 		return nfserr_resource;
3205 	p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
3206 						NFS4_VERIFIER_SIZE);
3207 	return 0;
3208 }
3209 
3210 static __be32
3211 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
3212 {
3213 	struct xdr_stream *xdr = &resp->xdr;
3214 	__be32 *p;
3215 
3216 	p = xdr_reserve_space(xdr, 20);
3217 	if (!p)
3218 		return nfserr_resource;
3219 	encode_cinfo(p, &create->cr_cinfo);
3220 	nfserr = nfsd4_encode_bitmap(xdr, create->cr_bmval[0],
3221 			create->cr_bmval[1], create->cr_bmval[2]);
3222 	return 0;
3223 }
3224 
3225 static __be32
3226 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
3227 {
3228 	struct svc_fh *fhp = getattr->ga_fhp;
3229 	struct xdr_stream *xdr = &resp->xdr;
3230 
3231 	return nfsd4_encode_fattr(xdr, fhp, fhp->fh_export, fhp->fh_dentry,
3232 				    getattr->ga_bmval, resp->rqstp, 0);
3233 }
3234 
3235 static __be32
3236 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
3237 {
3238 	struct xdr_stream *xdr = &resp->xdr;
3239 	struct svc_fh *fhp = *fhpp;
3240 	unsigned int len;
3241 	__be32 *p;
3242 
3243 	len = fhp->fh_handle.fh_size;
3244 	p = xdr_reserve_space(xdr, len + 4);
3245 	if (!p)
3246 		return nfserr_resource;
3247 	p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base, len);
3248 	return 0;
3249 }
3250 
3251 /*
3252 * Including all fields other than the name, a LOCK4denied structure requires
3253 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
3254 */
3255 static __be32
3256 nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld)
3257 {
3258 	struct xdr_netobj *conf = &ld->ld_owner;
3259 	__be32 *p;
3260 
3261 again:
3262 	p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len));
3263 	if (!p) {
3264 		/*
3265 		 * Don't fail to return the result just because we can't
3266 		 * return the conflicting open:
3267 		 */
3268 		if (conf->len) {
3269 			kfree(conf->data);
3270 			conf->len = 0;
3271 			conf->data = NULL;
3272 			goto again;
3273 		}
3274 		return nfserr_resource;
3275 	}
3276 	p = xdr_encode_hyper(p, ld->ld_start);
3277 	p = xdr_encode_hyper(p, ld->ld_length);
3278 	*p++ = cpu_to_be32(ld->ld_type);
3279 	if (conf->len) {
3280 		p = xdr_encode_opaque_fixed(p, &ld->ld_clientid, 8);
3281 		p = xdr_encode_opaque(p, conf->data, conf->len);
3282 		kfree(conf->data);
3283 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
3284 		p = xdr_encode_hyper(p, (u64)0); /* clientid */
3285 		*p++ = cpu_to_be32(0); /* length of owner name */
3286 	}
3287 	return nfserr_denied;
3288 }
3289 
3290 static __be32
3291 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
3292 {
3293 	struct xdr_stream *xdr = &resp->xdr;
3294 
3295 	if (!nfserr)
3296 		nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid);
3297 	else if (nfserr == nfserr_denied)
3298 		nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied);
3299 
3300 	return nfserr;
3301 }
3302 
3303 static __be32
3304 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
3305 {
3306 	struct xdr_stream *xdr = &resp->xdr;
3307 
3308 	if (nfserr == nfserr_denied)
3309 		nfsd4_encode_lock_denied(xdr, &lockt->lt_denied);
3310 	return nfserr;
3311 }
3312 
3313 static __be32
3314 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
3315 {
3316 	struct xdr_stream *xdr = &resp->xdr;
3317 
3318 	return nfsd4_encode_stateid(xdr, &locku->lu_stateid);
3319 }
3320 
3321 
3322 static __be32
3323 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
3324 {
3325 	struct xdr_stream *xdr = &resp->xdr;
3326 	__be32 *p;
3327 
3328 	p = xdr_reserve_space(xdr, 20);
3329 	if (!p)
3330 		return nfserr_resource;
3331 	p = encode_cinfo(p, &link->li_cinfo);
3332 	return 0;
3333 }
3334 
3335 
3336 static __be32
3337 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
3338 {
3339 	struct xdr_stream *xdr = &resp->xdr;
3340 	__be32 *p;
3341 
3342 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
3343 	if (nfserr)
3344 		return nfserr;
3345 	p = xdr_reserve_space(xdr, 24);
3346 	if (!p)
3347 		return nfserr_resource;
3348 	p = encode_cinfo(p, &open->op_cinfo);
3349 	*p++ = cpu_to_be32(open->op_rflags);
3350 
3351 	nfserr = nfsd4_encode_bitmap(xdr, open->op_bmval[0], open->op_bmval[1],
3352 					open->op_bmval[2]);
3353 	if (nfserr)
3354 		return nfserr;
3355 
3356 	p = xdr_reserve_space(xdr, 4);
3357 	if (!p)
3358 		return nfserr_resource;
3359 
3360 	*p++ = cpu_to_be32(open->op_delegate_type);
3361 	switch (open->op_delegate_type) {
3362 	case NFS4_OPEN_DELEGATE_NONE:
3363 		break;
3364 	case NFS4_OPEN_DELEGATE_READ:
3365 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3366 		if (nfserr)
3367 			return nfserr;
3368 		p = xdr_reserve_space(xdr, 20);
3369 		if (!p)
3370 			return nfserr_resource;
3371 		*p++ = cpu_to_be32(open->op_recall);
3372 
3373 		/*
3374 		 * TODO: ACE's in delegations
3375 		 */
3376 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3377 		*p++ = cpu_to_be32(0);
3378 		*p++ = cpu_to_be32(0);
3379 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3380 		break;
3381 	case NFS4_OPEN_DELEGATE_WRITE:
3382 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3383 		if (nfserr)
3384 			return nfserr;
3385 		p = xdr_reserve_space(xdr, 32);
3386 		if (!p)
3387 			return nfserr_resource;
3388 		*p++ = cpu_to_be32(0);
3389 
3390 		/*
3391 		 * TODO: space_limit's in delegations
3392 		 */
3393 		*p++ = cpu_to_be32(NFS4_LIMIT_SIZE);
3394 		*p++ = cpu_to_be32(~(u32)0);
3395 		*p++ = cpu_to_be32(~(u32)0);
3396 
3397 		/*
3398 		 * TODO: ACE's in delegations
3399 		 */
3400 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3401 		*p++ = cpu_to_be32(0);
3402 		*p++ = cpu_to_be32(0);
3403 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3404 		break;
3405 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
3406 		switch (open->op_why_no_deleg) {
3407 		case WND4_CONTENTION:
3408 		case WND4_RESOURCE:
3409 			p = xdr_reserve_space(xdr, 8);
3410 			if (!p)
3411 				return nfserr_resource;
3412 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3413 			/* deleg signaling not supported yet: */
3414 			*p++ = cpu_to_be32(0);
3415 			break;
3416 		default:
3417 			p = xdr_reserve_space(xdr, 4);
3418 			if (!p)
3419 				return nfserr_resource;
3420 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3421 		}
3422 		break;
3423 	default:
3424 		BUG();
3425 	}
3426 	/* XXX save filehandle here */
3427 	return 0;
3428 }
3429 
3430 static __be32
3431 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
3432 {
3433 	struct xdr_stream *xdr = &resp->xdr;
3434 
3435 	return nfsd4_encode_stateid(xdr, &oc->oc_resp_stateid);
3436 }
3437 
3438 static __be32
3439 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
3440 {
3441 	struct xdr_stream *xdr = &resp->xdr;
3442 
3443 	return nfsd4_encode_stateid(xdr, &od->od_stateid);
3444 }
3445 
3446 static __be32 nfsd4_encode_splice_read(
3447 				struct nfsd4_compoundres *resp,
3448 				struct nfsd4_read *read,
3449 				struct file *file, unsigned long maxcount)
3450 {
3451 	struct xdr_stream *xdr = &resp->xdr;
3452 	struct xdr_buf *buf = xdr->buf;
3453 	u32 eof;
3454 	long len;
3455 	int space_left;
3456 	__be32 nfserr;
3457 	__be32 *p = xdr->p - 2;
3458 
3459 	/* Make sure there will be room for padding if needed */
3460 	if (xdr->end - xdr->p < 1)
3461 		return nfserr_resource;
3462 
3463 	len = maxcount;
3464 	nfserr = nfsd_splice_read(read->rd_rqstp, read->rd_fhp,
3465 				  file, read->rd_offset, &maxcount);
3466 	read->rd_length = maxcount;
3467 	if (nfserr) {
3468 		/*
3469 		 * nfsd_splice_actor may have already messed with the
3470 		 * page length; reset it so as not to confuse
3471 		 * xdr_truncate_encode:
3472 		 */
3473 		buf->page_len = 0;
3474 		return nfserr;
3475 	}
3476 
3477 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3478 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3479 
3480 	*(p++) = htonl(eof);
3481 	*(p++) = htonl(maxcount);
3482 
3483 	buf->page_len = maxcount;
3484 	buf->len += maxcount;
3485 	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
3486 							/ PAGE_SIZE;
3487 
3488 	/* Use rest of head for padding and remaining ops: */
3489 	buf->tail[0].iov_base = xdr->p;
3490 	buf->tail[0].iov_len = 0;
3491 	xdr->iov = buf->tail;
3492 	if (maxcount&3) {
3493 		int pad = 4 - (maxcount&3);
3494 
3495 		*(xdr->p++) = 0;
3496 
3497 		buf->tail[0].iov_base += maxcount&3;
3498 		buf->tail[0].iov_len = pad;
3499 		buf->len += pad;
3500 	}
3501 
3502 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
3503 				buf->buflen - buf->len);
3504 	buf->buflen = buf->len + space_left;
3505 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
3506 
3507 	return 0;
3508 }
3509 
3510 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
3511 				 struct nfsd4_read *read,
3512 				 struct file *file, unsigned long maxcount)
3513 {
3514 	struct xdr_stream *xdr = &resp->xdr;
3515 	u32 eof;
3516 	int v;
3517 	int starting_len = xdr->buf->len - 8;
3518 	long len;
3519 	int thislen;
3520 	__be32 nfserr;
3521 	__be32 tmp;
3522 	__be32 *p;
3523 	u32 zzz = 0;
3524 	int pad;
3525 
3526 	len = maxcount;
3527 	v = 0;
3528 
3529 	thislen = min_t(long, len, ((void *)xdr->end - (void *)xdr->p));
3530 	p = xdr_reserve_space(xdr, (thislen+3)&~3);
3531 	WARN_ON_ONCE(!p);
3532 	resp->rqstp->rq_vec[v].iov_base = p;
3533 	resp->rqstp->rq_vec[v].iov_len = thislen;
3534 	v++;
3535 	len -= thislen;
3536 
3537 	while (len) {
3538 		thislen = min_t(long, len, PAGE_SIZE);
3539 		p = xdr_reserve_space(xdr, (thislen+3)&~3);
3540 		WARN_ON_ONCE(!p);
3541 		resp->rqstp->rq_vec[v].iov_base = p;
3542 		resp->rqstp->rq_vec[v].iov_len = thislen;
3543 		v++;
3544 		len -= thislen;
3545 	}
3546 	read->rd_vlen = v;
3547 
3548 	len = maxcount;
3549 	nfserr = nfsd_readv(resp->rqstp, read->rd_fhp, file, read->rd_offset,
3550 			    resp->rqstp->rq_vec, read->rd_vlen, &maxcount);
3551 	read->rd_length = maxcount;
3552 	if (nfserr)
3553 		return nfserr;
3554 	xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3));
3555 
3556 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3557 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3558 
3559 	tmp = htonl(eof);
3560 	write_bytes_to_xdr_buf(xdr->buf, starting_len    , &tmp, 4);
3561 	tmp = htonl(maxcount);
3562 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
3563 
3564 	pad = (maxcount&3) ? 4 - (maxcount&3) : 0;
3565 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 8 + maxcount,
3566 								&zzz, pad);
3567 	return 0;
3568 
3569 }
3570 
3571 static __be32
3572 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
3573 		  struct nfsd4_read *read)
3574 {
3575 	unsigned long maxcount;
3576 	struct xdr_stream *xdr = &resp->xdr;
3577 	struct file *file = read->rd_filp;
3578 	int starting_len = xdr->buf->len;
3579 	struct raparms *ra = NULL;
3580 	__be32 *p;
3581 
3582 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
3583 	if (!p) {
3584 		WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
3585 		return nfserr_resource;
3586 	}
3587 	if (resp->xdr.buf->page_len &&
3588 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
3589 		WARN_ON_ONCE(1);
3590 		return nfserr_resource;
3591 	}
3592 	xdr_commit_encode(xdr);
3593 
3594 	maxcount = svc_max_payload(resp->rqstp);
3595 	maxcount = min_t(unsigned long, maxcount,
3596 			 (xdr->buf->buflen - xdr->buf->len));
3597 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
3598 
3599 	if (read->rd_tmp_file)
3600 		ra = nfsd_init_raparms(file);
3601 
3602 	if (file->f_op->splice_read &&
3603 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
3604 		nfserr = nfsd4_encode_splice_read(resp, read, file, maxcount);
3605 	else
3606 		nfserr = nfsd4_encode_readv(resp, read, file, maxcount);
3607 
3608 	if (ra)
3609 		nfsd_put_raparams(file, ra);
3610 
3611 	if (nfserr)
3612 		xdr_truncate_encode(xdr, starting_len);
3613 
3614 	return nfserr;
3615 }
3616 
3617 static __be32
3618 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3619 {
3620 	int maxcount;
3621 	__be32 wire_count;
3622 	int zero = 0;
3623 	struct xdr_stream *xdr = &resp->xdr;
3624 	int length_offset = xdr->buf->len;
3625 	__be32 *p;
3626 
3627 	p = xdr_reserve_space(xdr, 4);
3628 	if (!p)
3629 		return nfserr_resource;
3630 	maxcount = PAGE_SIZE;
3631 
3632 	p = xdr_reserve_space(xdr, maxcount);
3633 	if (!p)
3634 		return nfserr_resource;
3635 	/*
3636 	 * XXX: By default, vfs_readlink() will truncate symlinks if they
3637 	 * would overflow the buffer.  Is this kosher in NFSv4?  If not, one
3638 	 * easy fix is: if vfs_readlink() precisely fills the buffer, assume
3639 	 * that truncation occurred, and return NFS4ERR_RESOURCE.
3640 	 */
3641 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
3642 						(char *)p, &maxcount);
3643 	if (nfserr == nfserr_isdir)
3644 		nfserr = nfserr_inval;
3645 	if (nfserr) {
3646 		xdr_truncate_encode(xdr, length_offset);
3647 		return nfserr;
3648 	}
3649 
3650 	wire_count = htonl(maxcount);
3651 	write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
3652 	xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
3653 	if (maxcount & 3)
3654 		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
3655 						&zero, 4 - (maxcount&3));
3656 	return 0;
3657 }
3658 
3659 static __be32
3660 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3661 {
3662 	int maxcount;
3663 	int bytes_left;
3664 	loff_t offset;
3665 	__be64 wire_offset;
3666 	struct xdr_stream *xdr = &resp->xdr;
3667 	int starting_len = xdr->buf->len;
3668 	__be32 *p;
3669 
3670 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3671 	if (!p)
3672 		return nfserr_resource;
3673 
3674 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3675 	*p++ = cpu_to_be32(0);
3676 	*p++ = cpu_to_be32(0);
3677 	resp->xdr.buf->head[0].iov_len = ((char *)resp->xdr.p)
3678 				- (char *)resp->xdr.buf->head[0].iov_base;
3679 
3680 	/*
3681 	 * Number of bytes left for directory entries allowing for the
3682 	 * final 8 bytes of the readdir and a following failed op:
3683 	 */
3684 	bytes_left = xdr->buf->buflen - xdr->buf->len
3685 			- COMPOUND_ERR_SLACK_SPACE - 8;
3686 	if (bytes_left < 0) {
3687 		nfserr = nfserr_resource;
3688 		goto err_no_verf;
3689 	}
3690 	maxcount = svc_max_payload(resp->rqstp);
3691 	maxcount = min_t(u32, readdir->rd_maxcount, maxcount);
3692 	/*
3693 	 * Note the rfc defines rd_maxcount as the size of the
3694 	 * READDIR4resok structure, which includes the verifier above
3695 	 * and the 8 bytes encoded at the end of this function:
3696 	 */
3697 	if (maxcount < 16) {
3698 		nfserr = nfserr_toosmall;
3699 		goto err_no_verf;
3700 	}
3701 	maxcount = min_t(int, maxcount-16, bytes_left);
3702 
3703 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
3704 	if (!readdir->rd_dircount)
3705 		readdir->rd_dircount = svc_max_payload(resp->rqstp);
3706 
3707 	readdir->xdr = xdr;
3708 	readdir->rd_maxcount = maxcount;
3709 	readdir->common.err = 0;
3710 	readdir->cookie_offset = 0;
3711 
3712 	offset = readdir->rd_cookie;
3713 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3714 			      &offset,
3715 			      &readdir->common, nfsd4_encode_dirent);
3716 	if (nfserr == nfs_ok &&
3717 	    readdir->common.err == nfserr_toosmall &&
3718 	    xdr->buf->len == starting_len + 8) {
3719 		/* nothing encoded; which limit did we hit?: */
3720 		if (maxcount - 16 < bytes_left)
3721 			/* It was the fault of rd_maxcount: */
3722 			nfserr = nfserr_toosmall;
3723 		else
3724 			/* We ran out of buffer space: */
3725 			nfserr = nfserr_resource;
3726 	}
3727 	if (nfserr)
3728 		goto err_no_verf;
3729 
3730 	if (readdir->cookie_offset) {
3731 		wire_offset = cpu_to_be64(offset);
3732 		write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset,
3733 							&wire_offset, 8);
3734 	}
3735 
3736 	p = xdr_reserve_space(xdr, 8);
3737 	if (!p) {
3738 		WARN_ON_ONCE(1);
3739 		goto err_no_verf;
3740 	}
3741 	*p++ = 0;	/* no more entries */
3742 	*p++ = htonl(readdir->common.err == nfserr_eof);
3743 
3744 	return 0;
3745 err_no_verf:
3746 	xdr_truncate_encode(xdr, starting_len);
3747 	return nfserr;
3748 }
3749 
3750 static __be32
3751 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3752 {
3753 	struct xdr_stream *xdr = &resp->xdr;
3754 	__be32 *p;
3755 
3756 	p = xdr_reserve_space(xdr, 20);
3757 	if (!p)
3758 		return nfserr_resource;
3759 	p = encode_cinfo(p, &remove->rm_cinfo);
3760 	return 0;
3761 }
3762 
3763 static __be32
3764 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3765 {
3766 	struct xdr_stream *xdr = &resp->xdr;
3767 	__be32 *p;
3768 
3769 	p = xdr_reserve_space(xdr, 40);
3770 	if (!p)
3771 		return nfserr_resource;
3772 	p = encode_cinfo(p, &rename->rn_sinfo);
3773 	p = encode_cinfo(p, &rename->rn_tinfo);
3774 	return 0;
3775 }
3776 
3777 static __be32
3778 nfsd4_do_encode_secinfo(struct xdr_stream *xdr, struct svc_export *exp)
3779 {
3780 	u32 i, nflavs, supported;
3781 	struct exp_flavor_info *flavs;
3782 	struct exp_flavor_info def_flavs[2];
3783 	__be32 *p, *flavorsp;
3784 	static bool report = true;
3785 
3786 	if (exp->ex_nflavors) {
3787 		flavs = exp->ex_flavors;
3788 		nflavs = exp->ex_nflavors;
3789 	} else { /* Handling of some defaults in absence of real secinfo: */
3790 		flavs = def_flavs;
3791 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3792 			nflavs = 2;
3793 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3794 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3795 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3796 			nflavs = 1;
3797 			flavs[0].pseudoflavor
3798 					= svcauth_gss_flavor(exp->ex_client);
3799 		} else {
3800 			nflavs = 1;
3801 			flavs[0].pseudoflavor
3802 					= exp->ex_client->flavour->flavour;
3803 		}
3804 	}
3805 
3806 	supported = 0;
3807 	p = xdr_reserve_space(xdr, 4);
3808 	if (!p)
3809 		return nfserr_resource;
3810 	flavorsp = p++;		/* to be backfilled later */
3811 
3812 	for (i = 0; i < nflavs; i++) {
3813 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
3814 		struct rpcsec_gss_info info;
3815 
3816 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
3817 			supported++;
3818 			p = xdr_reserve_space(xdr, 4 + 4 +
3819 					      XDR_LEN(info.oid.len) + 4 + 4);
3820 			if (!p)
3821 				return nfserr_resource;
3822 			*p++ = cpu_to_be32(RPC_AUTH_GSS);
3823 			p = xdr_encode_opaque(p,  info.oid.data, info.oid.len);
3824 			*p++ = cpu_to_be32(info.qop);
3825 			*p++ = cpu_to_be32(info.service);
3826 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
3827 			supported++;
3828 			p = xdr_reserve_space(xdr, 4);
3829 			if (!p)
3830 				return nfserr_resource;
3831 			*p++ = cpu_to_be32(pf);
3832 		} else {
3833 			if (report)
3834 				pr_warn("NFS: SECINFO: security flavor %u "
3835 					"is not supported\n", pf);
3836 		}
3837 	}
3838 
3839 	if (nflavs != supported)
3840 		report = false;
3841 	*flavorsp = htonl(supported);
3842 	return 0;
3843 }
3844 
3845 static __be32
3846 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3847 		     struct nfsd4_secinfo *secinfo)
3848 {
3849 	struct xdr_stream *xdr = &resp->xdr;
3850 
3851 	return nfsd4_do_encode_secinfo(xdr, secinfo->si_exp);
3852 }
3853 
3854 static __be32
3855 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3856 		     struct nfsd4_secinfo_no_name *secinfo)
3857 {
3858 	struct xdr_stream *xdr = &resp->xdr;
3859 
3860 	return nfsd4_do_encode_secinfo(xdr, secinfo->sin_exp);
3861 }
3862 
3863 /*
3864  * The SETATTR encode routine is special -- it always encodes a bitmap,
3865  * regardless of the error status.
3866  */
3867 static __be32
3868 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3869 {
3870 	struct xdr_stream *xdr = &resp->xdr;
3871 	__be32 *p;
3872 
3873 	p = xdr_reserve_space(xdr, 16);
3874 	if (!p)
3875 		return nfserr_resource;
3876 	if (nfserr) {
3877 		*p++ = cpu_to_be32(3);
3878 		*p++ = cpu_to_be32(0);
3879 		*p++ = cpu_to_be32(0);
3880 		*p++ = cpu_to_be32(0);
3881 	}
3882 	else {
3883 		*p++ = cpu_to_be32(3);
3884 		*p++ = cpu_to_be32(setattr->sa_bmval[0]);
3885 		*p++ = cpu_to_be32(setattr->sa_bmval[1]);
3886 		*p++ = cpu_to_be32(setattr->sa_bmval[2]);
3887 	}
3888 	return nfserr;
3889 }
3890 
3891 static __be32
3892 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3893 {
3894 	struct xdr_stream *xdr = &resp->xdr;
3895 	__be32 *p;
3896 
3897 	if (!nfserr) {
3898 		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
3899 		if (!p)
3900 			return nfserr_resource;
3901 		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
3902 		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
3903 						NFS4_VERIFIER_SIZE);
3904 	}
3905 	else if (nfserr == nfserr_clid_inuse) {
3906 		p = xdr_reserve_space(xdr, 8);
3907 		if (!p)
3908 			return nfserr_resource;
3909 		*p++ = cpu_to_be32(0);
3910 		*p++ = cpu_to_be32(0);
3911 	}
3912 	return nfserr;
3913 }
3914 
3915 static __be32
3916 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3917 {
3918 	struct xdr_stream *xdr = &resp->xdr;
3919 	__be32 *p;
3920 
3921 	p = xdr_reserve_space(xdr, 16);
3922 	if (!p)
3923 		return nfserr_resource;
3924 	*p++ = cpu_to_be32(write->wr_bytes_written);
3925 	*p++ = cpu_to_be32(write->wr_how_written);
3926 	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
3927 						NFS4_VERIFIER_SIZE);
3928 	return 0;
3929 }
3930 
3931 static __be32
3932 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
3933 			 struct nfsd4_exchange_id *exid)
3934 {
3935 	struct xdr_stream *xdr = &resp->xdr;
3936 	__be32 *p;
3937 	char *major_id;
3938 	char *server_scope;
3939 	int major_id_sz;
3940 	int server_scope_sz;
3941 	uint64_t minor_id = 0;
3942 
3943 	major_id = utsname()->nodename;
3944 	major_id_sz = strlen(major_id);
3945 	server_scope = utsname()->nodename;
3946 	server_scope_sz = strlen(server_scope);
3947 
3948 	p = xdr_reserve_space(xdr,
3949 		8 /* eir_clientid */ +
3950 		4 /* eir_sequenceid */ +
3951 		4 /* eir_flags */ +
3952 		4 /* spr_how */);
3953 	if (!p)
3954 		return nfserr_resource;
3955 
3956 	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
3957 	*p++ = cpu_to_be32(exid->seqid);
3958 	*p++ = cpu_to_be32(exid->flags);
3959 
3960 	*p++ = cpu_to_be32(exid->spa_how);
3961 
3962 	switch (exid->spa_how) {
3963 	case SP4_NONE:
3964 		break;
3965 	case SP4_MACH_CRED:
3966 		/* spo_must_enforce bitmap: */
3967 		nfserr = nfsd4_encode_bitmap(xdr,
3968 					exid->spo_must_enforce[0],
3969 					exid->spo_must_enforce[1],
3970 					exid->spo_must_enforce[2]);
3971 		if (nfserr)
3972 			return nfserr;
3973 		/* spo_must_allow bitmap: */
3974 		nfserr = nfsd4_encode_bitmap(xdr,
3975 					exid->spo_must_allow[0],
3976 					exid->spo_must_allow[1],
3977 					exid->spo_must_allow[2]);
3978 		if (nfserr)
3979 			return nfserr;
3980 		break;
3981 	default:
3982 		WARN_ON_ONCE(1);
3983 	}
3984 
3985 	p = xdr_reserve_space(xdr,
3986 		8 /* so_minor_id */ +
3987 		4 /* so_major_id.len */ +
3988 		(XDR_QUADLEN(major_id_sz) * 4) +
3989 		4 /* eir_server_scope.len */ +
3990 		(XDR_QUADLEN(server_scope_sz) * 4) +
3991 		4 /* eir_server_impl_id.count (0) */);
3992 	if (!p)
3993 		return nfserr_resource;
3994 
3995 	/* The server_owner struct */
3996 	p = xdr_encode_hyper(p, minor_id);      /* Minor id */
3997 	/* major id */
3998 	p = xdr_encode_opaque(p, major_id, major_id_sz);
3999 
4000 	/* Server scope */
4001 	p = xdr_encode_opaque(p, server_scope, server_scope_sz);
4002 
4003 	/* Implementation id */
4004 	*p++ = cpu_to_be32(0);	/* zero length nfs_impl_id4 array */
4005 	return 0;
4006 }
4007 
4008 static __be32
4009 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
4010 			    struct nfsd4_create_session *sess)
4011 {
4012 	struct xdr_stream *xdr = &resp->xdr;
4013 	__be32 *p;
4014 
4015 	p = xdr_reserve_space(xdr, 24);
4016 	if (!p)
4017 		return nfserr_resource;
4018 	p = xdr_encode_opaque_fixed(p, sess->sessionid.data,
4019 					NFS4_MAX_SESSIONID_LEN);
4020 	*p++ = cpu_to_be32(sess->seqid);
4021 	*p++ = cpu_to_be32(sess->flags);
4022 
4023 	p = xdr_reserve_space(xdr, 28);
4024 	if (!p)
4025 		return nfserr_resource;
4026 	*p++ = cpu_to_be32(0); /* headerpadsz */
4027 	*p++ = cpu_to_be32(sess->fore_channel.maxreq_sz);
4028 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_sz);
4029 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_cached);
4030 	*p++ = cpu_to_be32(sess->fore_channel.maxops);
4031 	*p++ = cpu_to_be32(sess->fore_channel.maxreqs);
4032 	*p++ = cpu_to_be32(sess->fore_channel.nr_rdma_attrs);
4033 
4034 	if (sess->fore_channel.nr_rdma_attrs) {
4035 		p = xdr_reserve_space(xdr, 4);
4036 		if (!p)
4037 			return nfserr_resource;
4038 		*p++ = cpu_to_be32(sess->fore_channel.rdma_attrs);
4039 	}
4040 
4041 	p = xdr_reserve_space(xdr, 28);
4042 	if (!p)
4043 		return nfserr_resource;
4044 	*p++ = cpu_to_be32(0); /* headerpadsz */
4045 	*p++ = cpu_to_be32(sess->back_channel.maxreq_sz);
4046 	*p++ = cpu_to_be32(sess->back_channel.maxresp_sz);
4047 	*p++ = cpu_to_be32(sess->back_channel.maxresp_cached);
4048 	*p++ = cpu_to_be32(sess->back_channel.maxops);
4049 	*p++ = cpu_to_be32(sess->back_channel.maxreqs);
4050 	*p++ = cpu_to_be32(sess->back_channel.nr_rdma_attrs);
4051 
4052 	if (sess->back_channel.nr_rdma_attrs) {
4053 		p = xdr_reserve_space(xdr, 4);
4054 		if (!p)
4055 			return nfserr_resource;
4056 		*p++ = cpu_to_be32(sess->back_channel.rdma_attrs);
4057 	}
4058 	return 0;
4059 }
4060 
4061 static __be32
4062 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
4063 		      struct nfsd4_sequence *seq)
4064 {
4065 	struct xdr_stream *xdr = &resp->xdr;
4066 	__be32 *p;
4067 
4068 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 20);
4069 	if (!p)
4070 		return nfserr_resource;
4071 	p = xdr_encode_opaque_fixed(p, seq->sessionid.data,
4072 					NFS4_MAX_SESSIONID_LEN);
4073 	*p++ = cpu_to_be32(seq->seqid);
4074 	*p++ = cpu_to_be32(seq->slotid);
4075 	/* Note slotid's are numbered from zero: */
4076 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_highest_slotid */
4077 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_target_highest_slotid */
4078 	*p++ = cpu_to_be32(seq->status_flags);
4079 
4080 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
4081 	return 0;
4082 }
4083 
4084 static __be32
4085 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
4086 			  struct nfsd4_test_stateid *test_stateid)
4087 {
4088 	struct xdr_stream *xdr = &resp->xdr;
4089 	struct nfsd4_test_stateid_id *stateid, *next;
4090 	__be32 *p;
4091 
4092 	p = xdr_reserve_space(xdr, 4 + (4 * test_stateid->ts_num_ids));
4093 	if (!p)
4094 		return nfserr_resource;
4095 	*p++ = htonl(test_stateid->ts_num_ids);
4096 
4097 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
4098 		*p++ = stateid->ts_id_status;
4099 	}
4100 
4101 	return 0;
4102 }
4103 
4104 #ifdef CONFIG_NFSD_PNFS
4105 static __be32
4106 nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
4107 		struct nfsd4_getdeviceinfo *gdev)
4108 {
4109 	struct xdr_stream *xdr = &resp->xdr;
4110 	const struct nfsd4_layout_ops *ops;
4111 	u32 starting_len = xdr->buf->len, needed_len;
4112 	__be32 *p;
4113 
4114 	p = xdr_reserve_space(xdr, 4);
4115 	if (!p)
4116 		return nfserr_resource;
4117 
4118 	*p++ = cpu_to_be32(gdev->gd_layout_type);
4119 
4120 	/* If maxcount is 0 then just update notifications */
4121 	if (gdev->gd_maxcount != 0) {
4122 		ops = nfsd4_layout_ops[gdev->gd_layout_type];
4123 		nfserr = ops->encode_getdeviceinfo(xdr, gdev);
4124 		if (nfserr) {
4125 			/*
4126 			 * We don't bother to burden the layout drivers with
4127 			 * enforcing gd_maxcount, just tell the client to
4128 			 * come back with a bigger buffer if it's not enough.
4129 			 */
4130 			if (xdr->buf->len + 4 > gdev->gd_maxcount)
4131 				goto toosmall;
4132 			return nfserr;
4133 		}
4134 	}
4135 
4136 	if (gdev->gd_notify_types) {
4137 		p = xdr_reserve_space(xdr, 4 + 4);
4138 		if (!p)
4139 			return nfserr_resource;
4140 		*p++ = cpu_to_be32(1);			/* bitmap length */
4141 		*p++ = cpu_to_be32(gdev->gd_notify_types);
4142 	} else {
4143 		p = xdr_reserve_space(xdr, 4);
4144 		if (!p)
4145 			return nfserr_resource;
4146 		*p++ = 0;
4147 	}
4148 
4149 	return 0;
4150 toosmall:
4151 	dprintk("%s: maxcount too small\n", __func__);
4152 	needed_len = xdr->buf->len + 4 /* notifications */;
4153 	xdr_truncate_encode(xdr, starting_len);
4154 	p = xdr_reserve_space(xdr, 4);
4155 	if (!p)
4156 		return nfserr_resource;
4157 	*p++ = cpu_to_be32(needed_len);
4158 	return nfserr_toosmall;
4159 }
4160 
4161 static __be32
4162 nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr,
4163 		struct nfsd4_layoutget *lgp)
4164 {
4165 	struct xdr_stream *xdr = &resp->xdr;
4166 	const struct nfsd4_layout_ops *ops;
4167 	__be32 *p;
4168 
4169 	p = xdr_reserve_space(xdr, 36 + sizeof(stateid_opaque_t));
4170 	if (!p)
4171 		return nfserr_resource;
4172 
4173 	*p++ = cpu_to_be32(1);	/* we always set return-on-close */
4174 	*p++ = cpu_to_be32(lgp->lg_sid.si_generation);
4175 	p = xdr_encode_opaque_fixed(p, &lgp->lg_sid.si_opaque,
4176 				    sizeof(stateid_opaque_t));
4177 
4178 	*p++ = cpu_to_be32(1);	/* we always return a single layout */
4179 	p = xdr_encode_hyper(p, lgp->lg_seg.offset);
4180 	p = xdr_encode_hyper(p, lgp->lg_seg.length);
4181 	*p++ = cpu_to_be32(lgp->lg_seg.iomode);
4182 	*p++ = cpu_to_be32(lgp->lg_layout_type);
4183 
4184 	ops = nfsd4_layout_ops[lgp->lg_layout_type];
4185 	return ops->encode_layoutget(xdr, lgp);
4186 }
4187 
4188 static __be32
4189 nfsd4_encode_layoutcommit(struct nfsd4_compoundres *resp, __be32 nfserr,
4190 			  struct nfsd4_layoutcommit *lcp)
4191 {
4192 	struct xdr_stream *xdr = &resp->xdr;
4193 	__be32 *p;
4194 
4195 	p = xdr_reserve_space(xdr, 4);
4196 	if (!p)
4197 		return nfserr_resource;
4198 	*p++ = cpu_to_be32(lcp->lc_size_chg);
4199 	if (lcp->lc_size_chg) {
4200 		p = xdr_reserve_space(xdr, 8);
4201 		if (!p)
4202 			return nfserr_resource;
4203 		p = xdr_encode_hyper(p, lcp->lc_newsize);
4204 	}
4205 
4206 	return 0;
4207 }
4208 
4209 static __be32
4210 nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
4211 		struct nfsd4_layoutreturn *lrp)
4212 {
4213 	struct xdr_stream *xdr = &resp->xdr;
4214 	__be32 *p;
4215 
4216 	p = xdr_reserve_space(xdr, 4);
4217 	if (!p)
4218 		return nfserr_resource;
4219 	*p++ = cpu_to_be32(lrp->lrs_present);
4220 	if (lrp->lrs_present)
4221 		return nfsd4_encode_stateid(xdr, &lrp->lr_sid);
4222 	return 0;
4223 }
4224 #endif /* CONFIG_NFSD_PNFS */
4225 
4226 static __be32
4227 nfsd42_encode_write_res(struct nfsd4_compoundres *resp,
4228 		struct nfsd42_write_res *write, bool sync)
4229 {
4230 	__be32 *p;
4231 	p = xdr_reserve_space(&resp->xdr, 4);
4232 	if (!p)
4233 		return nfserr_resource;
4234 
4235 	if (sync)
4236 		*p++ = cpu_to_be32(0);
4237 	else {
4238 		__be32 nfserr;
4239 		*p++ = cpu_to_be32(1);
4240 		nfserr = nfsd4_encode_stateid(&resp->xdr, &write->cb_stateid);
4241 		if (nfserr)
4242 			return nfserr;
4243 	}
4244 	p = xdr_reserve_space(&resp->xdr, 8 + 4 + NFS4_VERIFIER_SIZE);
4245 	if (!p)
4246 		return nfserr_resource;
4247 
4248 	p = xdr_encode_hyper(p, write->wr_bytes_written);
4249 	*p++ = cpu_to_be32(write->wr_stable_how);
4250 	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
4251 				    NFS4_VERIFIER_SIZE);
4252 	return nfs_ok;
4253 }
4254 
4255 static __be32
4256 nfsd4_encode_copy(struct nfsd4_compoundres *resp, __be32 nfserr,
4257 		  struct nfsd4_copy *copy)
4258 {
4259 	__be32 *p;
4260 
4261 	nfserr = nfsd42_encode_write_res(resp, &copy->cp_res,
4262 			copy->cp_synchronous);
4263 	if (nfserr)
4264 		return nfserr;
4265 
4266 	p = xdr_reserve_space(&resp->xdr, 4 + 4);
4267 	*p++ = xdr_one; /* cr_consecutive */
4268 	*p++ = cpu_to_be32(copy->cp_synchronous);
4269 	return 0;
4270 }
4271 
4272 static __be32
4273 nfsd4_encode_offload_status(struct nfsd4_compoundres *resp, __be32 nfserr,
4274 			    struct nfsd4_offload_status *os)
4275 {
4276 	struct xdr_stream *xdr = &resp->xdr;
4277 	__be32 *p;
4278 
4279 	p = xdr_reserve_space(xdr, 8 + 4);
4280 	if (!p)
4281 		return nfserr_resource;
4282 	p = xdr_encode_hyper(p, os->count);
4283 	*p++ = cpu_to_be32(0);
4284 
4285 	return nfserr;
4286 }
4287 
4288 static __be32
4289 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
4290 		  struct nfsd4_seek *seek)
4291 {
4292 	__be32 *p;
4293 
4294 	p = xdr_reserve_space(&resp->xdr, 4 + 8);
4295 	*p++ = cpu_to_be32(seek->seek_eof);
4296 	p = xdr_encode_hyper(p, seek->seek_pos);
4297 
4298 	return 0;
4299 }
4300 
4301 static __be32
4302 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
4303 {
4304 	return nfserr;
4305 }
4306 
4307 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
4308 
4309 /*
4310  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
4311  * since we don't need to filter out obsolete ops as this is
4312  * done in the decoding phase.
4313  */
4314 static const nfsd4_enc nfsd4_enc_ops[] = {
4315 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
4316 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
4317 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
4318 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
4319 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
4320 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4321 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
4322 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
4323 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
4324 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
4325 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
4326 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
4327 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
4328 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
4329 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4330 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
4331 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
4332 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
4333 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
4334 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4335 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
4336 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4337 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
4338 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
4339 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
4340 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
4341 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
4342 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
4343 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
4344 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
4345 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
4346 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
4347 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
4348 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
4349 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4350 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
4351 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
4352 
4353 	/* NFSv4.1 operations */
4354 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
4355 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
4356 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
4357 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
4358 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
4359 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
4360 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4361 #ifdef CONFIG_NFSD_PNFS
4362 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_getdeviceinfo,
4363 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4364 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_layoutcommit,
4365 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_layoutget,
4366 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_layoutreturn,
4367 #else
4368 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
4369 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4370 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
4371 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
4372 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4373 #endif
4374 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
4375 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
4376 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
4377 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
4378 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4379 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
4380 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
4381 
4382 	/* NFSv4.2 operations */
4383 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4384 	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_copy,
4385 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
4386 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4387 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
4388 	[OP_LAYOUTERROR]	= (nfsd4_enc)nfsd4_encode_noop,
4389 	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,
4390 	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,
4391 	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_offload_status,
4392 	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_noop,
4393 	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,
4394 	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,
4395 	[OP_CLONE]		= (nfsd4_enc)nfsd4_encode_noop,
4396 };
4397 
4398 /*
4399  * Calculate whether we still have space to encode repsize bytes.
4400  * There are two considerations:
4401  *     - For NFS versions >=4.1, the size of the reply must stay within
4402  *       session limits
4403  *     - For all NFS versions, we must stay within limited preallocated
4404  *       buffer space.
4405  *
4406  * This is called before the operation is processed, so can only provide
4407  * an upper estimate.  For some nonidempotent operations (such as
4408  * getattr), it's not necessarily a problem if that estimate is wrong,
4409  * as we can fail it after processing without significant side effects.
4410  */
4411 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
4412 {
4413 	struct xdr_buf *buf = &resp->rqstp->rq_res;
4414 	struct nfsd4_slot *slot = resp->cstate.slot;
4415 
4416 	if (buf->len + respsize <= buf->buflen)
4417 		return nfs_ok;
4418 	if (!nfsd4_has_session(&resp->cstate))
4419 		return nfserr_resource;
4420 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
4421 		WARN_ON_ONCE(1);
4422 		return nfserr_rep_too_big_to_cache;
4423 	}
4424 	return nfserr_rep_too_big;
4425 }
4426 
4427 void
4428 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
4429 {
4430 	struct xdr_stream *xdr = &resp->xdr;
4431 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
4432 	struct svc_rqst *rqstp = resp->rqstp;
4433 	const struct nfsd4_operation *opdesc = op->opdesc;
4434 	int post_err_offset;
4435 	nfsd4_enc encoder;
4436 	__be32 *p;
4437 
4438 	p = xdr_reserve_space(xdr, 8);
4439 	if (!p) {
4440 		WARN_ON_ONCE(1);
4441 		return;
4442 	}
4443 	*p++ = cpu_to_be32(op->opnum);
4444 	post_err_offset = xdr->buf->len;
4445 
4446 	if (op->opnum == OP_ILLEGAL)
4447 		goto status;
4448 	if (op->status && opdesc &&
4449 			!(opdesc->op_flags & OP_NONTRIVIAL_ERROR_ENCODE))
4450 		goto status;
4451 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
4452 	       !nfsd4_enc_ops[op->opnum]);
4453 	encoder = nfsd4_enc_ops[op->opnum];
4454 	op->status = encoder(resp, op->status, &op->u);
4455 	if (opdesc && opdesc->op_release)
4456 		opdesc->op_release(&op->u);
4457 	xdr_commit_encode(xdr);
4458 
4459 	/* nfsd4_check_resp_size guarantees enough room for error status */
4460 	if (!op->status) {
4461 		int space_needed = 0;
4462 		if (!nfsd4_last_compound_op(rqstp))
4463 			space_needed = COMPOUND_ERR_SLACK_SPACE;
4464 		op->status = nfsd4_check_resp_size(resp, space_needed);
4465 	}
4466 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
4467 		struct nfsd4_slot *slot = resp->cstate.slot;
4468 
4469 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
4470 			op->status = nfserr_rep_too_big_to_cache;
4471 		else
4472 			op->status = nfserr_rep_too_big;
4473 	}
4474 	if (op->status == nfserr_resource ||
4475 	    op->status == nfserr_rep_too_big ||
4476 	    op->status == nfserr_rep_too_big_to_cache) {
4477 		/*
4478 		 * The operation may have already been encoded or
4479 		 * partially encoded.  No op returns anything additional
4480 		 * in the case of one of these three errors, so we can
4481 		 * just truncate back to after the status.  But it's a
4482 		 * bug if we had to do this on a non-idempotent op:
4483 		 */
4484 		warn_on_nonidempotent_op(op);
4485 		xdr_truncate_encode(xdr, post_err_offset);
4486 	}
4487 	if (so) {
4488 		int len = xdr->buf->len - post_err_offset;
4489 
4490 		so->so_replay.rp_status = op->status;
4491 		so->so_replay.rp_buflen = len;
4492 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
4493 						so->so_replay.rp_buf, len);
4494 	}
4495 status:
4496 	/* Note that op->status is already in network byte order: */
4497 	write_bytes_to_xdr_buf(xdr->buf, post_err_offset - 4, &op->status, 4);
4498 }
4499 
4500 /*
4501  * Encode the reply stored in the stateowner reply cache
4502  *
4503  * XDR note: do not encode rp->rp_buflen: the buffer contains the
4504  * previously sent already encoded operation.
4505  */
4506 void
4507 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
4508 {
4509 	__be32 *p;
4510 	struct nfs4_replay *rp = op->replay;
4511 
4512 	BUG_ON(!rp);
4513 
4514 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
4515 	if (!p) {
4516 		WARN_ON_ONCE(1);
4517 		return;
4518 	}
4519 	*p++ = cpu_to_be32(op->opnum);
4520 	*p++ = rp->rp_status;  /* already xdr'ed */
4521 
4522 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
4523 }
4524 
4525 int
4526 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p)
4527 {
4528         return xdr_ressize_check(rqstp, p);
4529 }
4530 
4531 void nfsd4_release_compoundargs(struct svc_rqst *rqstp)
4532 {
4533 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4534 
4535 	if (args->ops != args->iops) {
4536 		kfree(args->ops);
4537 		args->ops = args->iops;
4538 	}
4539 	kfree(args->tmpp);
4540 	args->tmpp = NULL;
4541 	while (args->to_free) {
4542 		struct svcxdr_tmpbuf *tb = args->to_free;
4543 		args->to_free = tb->next;
4544 		kfree(tb);
4545 	}
4546 }
4547 
4548 int
4549 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p)
4550 {
4551 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4552 
4553 	if (rqstp->rq_arg.head[0].iov_len % 4) {
4554 		/* client is nuts */
4555 		dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)",
4556 			__func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid));
4557 		return 0;
4558 	}
4559 	args->p = p;
4560 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
4561 	args->pagelist = rqstp->rq_arg.pages;
4562 	args->pagelen = rqstp->rq_arg.page_len;
4563 	args->tail = false;
4564 	args->tmpp = NULL;
4565 	args->to_free = NULL;
4566 	args->ops = args->iops;
4567 	args->rqstp = rqstp;
4568 
4569 	return !nfsd4_decode_compound(args);
4570 }
4571 
4572 int
4573 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p)
4574 {
4575 	/*
4576 	 * All that remains is to write the tag and operation count...
4577 	 */
4578 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
4579 	struct xdr_buf *buf = resp->xdr.buf;
4580 
4581 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
4582 				 buf->tail[0].iov_len);
4583 
4584 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
4585 
4586 	p = resp->tagp;
4587 	*p++ = htonl(resp->taglen);
4588 	memcpy(p, resp->tag, resp->taglen);
4589 	p += XDR_QUADLEN(resp->taglen);
4590 	*p++ = htonl(resp->opcnt);
4591 
4592 	nfsd4_sequence_done(resp);
4593 	return 1;
4594 }
4595 
4596 /*
4597  * Local variables:
4598  *  c-basic-offset: 8
4599  * End:
4600  */
4601