xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision dea54fba)
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/fs_struct.h>
37 #include <linux/file.h>
38 #include <linux/slab.h>
39 #include <linux/namei.h>
40 #include <linux/statfs.h>
41 #include <linux/utsname.h>
42 #include <linux/pagemap.h>
43 #include <linux/sunrpc/svcauth_gss.h>
44 
45 #include "idmap.h"
46 #include "acl.h"
47 #include "xdr4.h"
48 #include "vfs.h"
49 #include "state.h"
50 #include "cache.h"
51 #include "netns.h"
52 #include "pnfs.h"
53 
54 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
55 #include <linux/security.h>
56 #endif
57 
58 
59 #define NFSDDBG_FACILITY		NFSDDBG_XDR
60 
61 const u32 nfsd_suppattrs[3][3] = {
62 	{NFSD4_SUPPORTED_ATTRS_WORD0,
63 	 NFSD4_SUPPORTED_ATTRS_WORD1,
64 	 NFSD4_SUPPORTED_ATTRS_WORD2},
65 
66 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
67 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
68 	 NFSD4_1_SUPPORTED_ATTRS_WORD2},
69 
70 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
71 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
72 	 NFSD4_2_SUPPORTED_ATTRS_WORD2},
73 };
74 
75 /*
76  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
77  * directory in order to indicate to the client that a filesystem boundary is present
78  * We use a fixed fsid for a referral
79  */
80 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
81 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
82 
83 static __be32
84 check_filename(char *str, int len)
85 {
86 	int i;
87 
88 	if (len == 0)
89 		return nfserr_inval;
90 	if (isdotent(str, len))
91 		return nfserr_badname;
92 	for (i = 0; i < len; i++)
93 		if (str[i] == '/')
94 			return nfserr_badname;
95 	return 0;
96 }
97 
98 #define DECODE_HEAD				\
99 	__be32 *p;				\
100 	__be32 status
101 #define DECODE_TAIL				\
102 	status = 0;				\
103 out:						\
104 	return status;				\
105 xdr_error:					\
106 	dprintk("NFSD: xdr error (%s:%d)\n",	\
107 			__FILE__, __LINE__);	\
108 	status = nfserr_bad_xdr;		\
109 	goto out
110 
111 #define READMEM(x,nbytes) do {			\
112 	x = (char *)p;				\
113 	p += XDR_QUADLEN(nbytes);		\
114 } while (0)
115 #define SAVEMEM(x,nbytes) do {			\
116 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
117  		savemem(argp, p, nbytes) :	\
118  		(char *)p)) {			\
119 		dprintk("NFSD: xdr error (%s:%d)\n", \
120 				__FILE__, __LINE__); \
121 		goto xdr_error;			\
122 		}				\
123 	p += XDR_QUADLEN(nbytes);		\
124 } while (0)
125 #define COPYMEM(x,nbytes) do {			\
126 	memcpy((x), p, nbytes);			\
127 	p += XDR_QUADLEN(nbytes);		\
128 } while (0)
129 
130 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
131 #define READ_BUF(nbytes)  do {			\
132 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
133 		p = argp->p;			\
134 		argp->p += XDR_QUADLEN(nbytes);	\
135 	} else if (!(p = read_buf(argp, nbytes))) { \
136 		dprintk("NFSD: xdr error (%s:%d)\n", \
137 				__FILE__, __LINE__); \
138 		goto xdr_error;			\
139 	}					\
140 } while (0)
141 
142 static void next_decode_page(struct nfsd4_compoundargs *argp)
143 {
144 	argp->p = page_address(argp->pagelist[0]);
145 	argp->pagelist++;
146 	if (argp->pagelen < PAGE_SIZE) {
147 		argp->end = argp->p + XDR_QUADLEN(argp->pagelen);
148 		argp->pagelen = 0;
149 	} else {
150 		argp->end = argp->p + (PAGE_SIZE>>2);
151 		argp->pagelen -= PAGE_SIZE;
152 	}
153 }
154 
155 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
156 {
157 	/* We want more bytes than seem to be available.
158 	 * Maybe we need a new page, maybe we have just run out
159 	 */
160 	unsigned int avail = (char *)argp->end - (char *)argp->p;
161 	__be32 *p;
162 	if (avail + argp->pagelen < nbytes)
163 		return NULL;
164 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
165 		return NULL;
166 	/* ok, we can do it with the current plus the next page */
167 	if (nbytes <= sizeof(argp->tmp))
168 		p = argp->tmp;
169 	else {
170 		kfree(argp->tmpp);
171 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
172 		if (!p)
173 			return NULL;
174 
175 	}
176 	/*
177 	 * The following memcpy is safe because read_buf is always
178 	 * called with nbytes > avail, and the two cases above both
179 	 * guarantee p points to at least nbytes bytes.
180 	 */
181 	memcpy(p, argp->p, avail);
182 	next_decode_page(argp);
183 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
184 	argp->p += XDR_QUADLEN(nbytes - avail);
185 	return p;
186 }
187 
188 static int zero_clientid(clientid_t *clid)
189 {
190 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
191 }
192 
193 /**
194  * svcxdr_tmpalloc - allocate memory to be freed after compound processing
195  * @argp: NFSv4 compound argument structure
196  * @p: pointer to be freed (with kfree())
197  *
198  * Marks @p to be freed when processing the compound operation
199  * described in @argp finishes.
200  */
201 static void *
202 svcxdr_tmpalloc(struct nfsd4_compoundargs *argp, u32 len)
203 {
204 	struct svcxdr_tmpbuf *tb;
205 
206 	tb = kmalloc(sizeof(*tb) + len, GFP_KERNEL);
207 	if (!tb)
208 		return NULL;
209 	tb->next = argp->to_free;
210 	argp->to_free = tb;
211 	return tb->buf;
212 }
213 
214 /*
215  * For xdr strings that need to be passed to other kernel api's
216  * as null-terminated strings.
217  *
218  * Note null-terminating in place usually isn't safe since the
219  * buffer might end on a page boundary.
220  */
221 static char *
222 svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len)
223 {
224 	char *p = svcxdr_tmpalloc(argp, len + 1);
225 
226 	if (!p)
227 		return NULL;
228 	memcpy(p, buf, len);
229 	p[len] = '\0';
230 	return p;
231 }
232 
233 /**
234  * savemem - duplicate a chunk of memory for later processing
235  * @argp: NFSv4 compound argument structure to be freed with
236  * @p: pointer to be duplicated
237  * @nbytes: length to be duplicated
238  *
239  * Returns a pointer to a copy of @nbytes bytes of memory at @p
240  * that are preserved until processing of the NFSv4 compound
241  * operation described by @argp finishes.
242  */
243 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
244 {
245 	void *ret;
246 
247 	ret = svcxdr_tmpalloc(argp, nbytes);
248 	if (!ret)
249 		return NULL;
250 	memcpy(ret, p, nbytes);
251 	return ret;
252 }
253 
254 /*
255  * We require the high 32 bits of 'seconds' to be 0, and
256  * we ignore all 32 bits of 'nseconds'.
257  */
258 static __be32
259 nfsd4_decode_time(struct nfsd4_compoundargs *argp, struct timespec *tv)
260 {
261 	DECODE_HEAD;
262 	u64 sec;
263 
264 	READ_BUF(12);
265 	p = xdr_decode_hyper(p, &sec);
266 	tv->tv_sec = sec;
267 	tv->tv_nsec = be32_to_cpup(p++);
268 	if (tv->tv_nsec >= (u32)1000000000)
269 		return nfserr_inval;
270 
271 	DECODE_TAIL;
272 }
273 
274 static __be32
275 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
276 {
277 	u32 bmlen;
278 	DECODE_HEAD;
279 
280 	bmval[0] = 0;
281 	bmval[1] = 0;
282 	bmval[2] = 0;
283 
284 	READ_BUF(4);
285 	bmlen = be32_to_cpup(p++);
286 	if (bmlen > 1000)
287 		goto xdr_error;
288 
289 	READ_BUF(bmlen << 2);
290 	if (bmlen > 0)
291 		bmval[0] = be32_to_cpup(p++);
292 	if (bmlen > 1)
293 		bmval[1] = be32_to_cpup(p++);
294 	if (bmlen > 2)
295 		bmval[2] = be32_to_cpup(p++);
296 
297 	DECODE_TAIL;
298 }
299 
300 static __be32
301 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
302 		   struct iattr *iattr, struct nfs4_acl **acl,
303 		   struct xdr_netobj *label, int *umask)
304 {
305 	int expected_len, len = 0;
306 	u32 dummy32;
307 	char *buf;
308 
309 	DECODE_HEAD;
310 	iattr->ia_valid = 0;
311 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
312 		return status;
313 
314 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
315 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
316 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2) {
317 		if (nfsd_attrs_supported(argp->minorversion, bmval))
318 			return nfserr_inval;
319 		return nfserr_attrnotsupp;
320 	}
321 
322 	READ_BUF(4);
323 	expected_len = be32_to_cpup(p++);
324 
325 	if (bmval[0] & FATTR4_WORD0_SIZE) {
326 		READ_BUF(8);
327 		len += 8;
328 		p = xdr_decode_hyper(p, &iattr->ia_size);
329 		iattr->ia_valid |= ATTR_SIZE;
330 	}
331 	if (bmval[0] & FATTR4_WORD0_ACL) {
332 		u32 nace;
333 		struct nfs4_ace *ace;
334 
335 		READ_BUF(4); len += 4;
336 		nace = be32_to_cpup(p++);
337 
338 		if (nace > NFS4_ACL_MAX)
339 			return nfserr_fbig;
340 
341 		*acl = svcxdr_tmpalloc(argp, nfs4_acl_bytes(nace));
342 		if (*acl == NULL)
343 			return nfserr_jukebox;
344 
345 		(*acl)->naces = nace;
346 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
347 			READ_BUF(16); len += 16;
348 			ace->type = be32_to_cpup(p++);
349 			ace->flag = be32_to_cpup(p++);
350 			ace->access_mask = be32_to_cpup(p++);
351 			dummy32 = be32_to_cpup(p++);
352 			READ_BUF(dummy32);
353 			len += XDR_QUADLEN(dummy32) << 2;
354 			READMEM(buf, dummy32);
355 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
356 			status = nfs_ok;
357 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
358 				;
359 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
360 				status = nfsd_map_name_to_gid(argp->rqstp,
361 						buf, dummy32, &ace->who_gid);
362 			else
363 				status = nfsd_map_name_to_uid(argp->rqstp,
364 						buf, dummy32, &ace->who_uid);
365 			if (status)
366 				return status;
367 		}
368 	} else
369 		*acl = NULL;
370 	if (bmval[1] & FATTR4_WORD1_MODE) {
371 		READ_BUF(4);
372 		len += 4;
373 		iattr->ia_mode = be32_to_cpup(p++);
374 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
375 		iattr->ia_valid |= ATTR_MODE;
376 	}
377 	if (bmval[1] & FATTR4_WORD1_OWNER) {
378 		READ_BUF(4);
379 		len += 4;
380 		dummy32 = be32_to_cpup(p++);
381 		READ_BUF(dummy32);
382 		len += (XDR_QUADLEN(dummy32) << 2);
383 		READMEM(buf, dummy32);
384 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
385 			return status;
386 		iattr->ia_valid |= ATTR_UID;
387 	}
388 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
389 		READ_BUF(4);
390 		len += 4;
391 		dummy32 = be32_to_cpup(p++);
392 		READ_BUF(dummy32);
393 		len += (XDR_QUADLEN(dummy32) << 2);
394 		READMEM(buf, dummy32);
395 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
396 			return status;
397 		iattr->ia_valid |= ATTR_GID;
398 	}
399 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
400 		READ_BUF(4);
401 		len += 4;
402 		dummy32 = be32_to_cpup(p++);
403 		switch (dummy32) {
404 		case NFS4_SET_TO_CLIENT_TIME:
405 			len += 12;
406 			status = nfsd4_decode_time(argp, &iattr->ia_atime);
407 			if (status)
408 				return status;
409 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
410 			break;
411 		case NFS4_SET_TO_SERVER_TIME:
412 			iattr->ia_valid |= ATTR_ATIME;
413 			break;
414 		default:
415 			goto xdr_error;
416 		}
417 	}
418 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
419 		READ_BUF(4);
420 		len += 4;
421 		dummy32 = be32_to_cpup(p++);
422 		switch (dummy32) {
423 		case NFS4_SET_TO_CLIENT_TIME:
424 			len += 12;
425 			status = nfsd4_decode_time(argp, &iattr->ia_mtime);
426 			if (status)
427 				return status;
428 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
429 			break;
430 		case NFS4_SET_TO_SERVER_TIME:
431 			iattr->ia_valid |= ATTR_MTIME;
432 			break;
433 		default:
434 			goto xdr_error;
435 		}
436 	}
437 
438 	label->len = 0;
439 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
440 	if (bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
441 		READ_BUF(4);
442 		len += 4;
443 		dummy32 = be32_to_cpup(p++); /* lfs: we don't use it */
444 		READ_BUF(4);
445 		len += 4;
446 		dummy32 = be32_to_cpup(p++); /* pi: we don't use it either */
447 		READ_BUF(4);
448 		len += 4;
449 		dummy32 = be32_to_cpup(p++);
450 		READ_BUF(dummy32);
451 		if (dummy32 > NFS4_MAXLABELLEN)
452 			return nfserr_badlabel;
453 		len += (XDR_QUADLEN(dummy32) << 2);
454 		READMEM(buf, dummy32);
455 		label->len = dummy32;
456 		label->data = svcxdr_dupstr(argp, buf, dummy32);
457 		if (!label->data)
458 			return nfserr_jukebox;
459 	}
460 #endif
461 	if (bmval[2] & FATTR4_WORD2_MODE_UMASK) {
462 		if (!umask)
463 			goto xdr_error;
464 		READ_BUF(8);
465 		len += 8;
466 		dummy32 = be32_to_cpup(p++);
467 		iattr->ia_mode = dummy32 & (S_IFMT | S_IALLUGO);
468 		dummy32 = be32_to_cpup(p++);
469 		*umask = dummy32 & S_IRWXUGO;
470 		iattr->ia_valid |= ATTR_MODE;
471 	}
472 	if (len != expected_len)
473 		goto xdr_error;
474 
475 	DECODE_TAIL;
476 }
477 
478 static __be32
479 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
480 {
481 	DECODE_HEAD;
482 
483 	READ_BUF(sizeof(stateid_t));
484 	sid->si_generation = be32_to_cpup(p++);
485 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
486 
487 	DECODE_TAIL;
488 }
489 
490 static __be32
491 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
492 {
493 	DECODE_HEAD;
494 
495 	READ_BUF(4);
496 	access->ac_req_access = be32_to_cpup(p++);
497 
498 	DECODE_TAIL;
499 }
500 
501 static __be32 nfsd4_decode_cb_sec(struct nfsd4_compoundargs *argp, struct nfsd4_cb_sec *cbs)
502 {
503 	DECODE_HEAD;
504 	u32 dummy, uid, gid;
505 	char *machine_name;
506 	int i;
507 	int nr_secflavs;
508 
509 	/* callback_sec_params4 */
510 	READ_BUF(4);
511 	nr_secflavs = be32_to_cpup(p++);
512 	if (nr_secflavs)
513 		cbs->flavor = (u32)(-1);
514 	else
515 		/* Is this legal? Be generous, take it to mean AUTH_NONE: */
516 		cbs->flavor = 0;
517 	for (i = 0; i < nr_secflavs; ++i) {
518 		READ_BUF(4);
519 		dummy = be32_to_cpup(p++);
520 		switch (dummy) {
521 		case RPC_AUTH_NULL:
522 			/* Nothing to read */
523 			if (cbs->flavor == (u32)(-1))
524 				cbs->flavor = RPC_AUTH_NULL;
525 			break;
526 		case RPC_AUTH_UNIX:
527 			READ_BUF(8);
528 			/* stamp */
529 			dummy = be32_to_cpup(p++);
530 
531 			/* machine name */
532 			dummy = be32_to_cpup(p++);
533 			READ_BUF(dummy);
534 			SAVEMEM(machine_name, dummy);
535 
536 			/* uid, gid */
537 			READ_BUF(8);
538 			uid = be32_to_cpup(p++);
539 			gid = be32_to_cpup(p++);
540 
541 			/* more gids */
542 			READ_BUF(4);
543 			dummy = be32_to_cpup(p++);
544 			READ_BUF(dummy * 4);
545 			if (cbs->flavor == (u32)(-1)) {
546 				kuid_t kuid = make_kuid(&init_user_ns, uid);
547 				kgid_t kgid = make_kgid(&init_user_ns, gid);
548 				if (uid_valid(kuid) && gid_valid(kgid)) {
549 					cbs->uid = kuid;
550 					cbs->gid = kgid;
551 					cbs->flavor = RPC_AUTH_UNIX;
552 				} else {
553 					dprintk("RPC_AUTH_UNIX with invalid"
554 						"uid or gid ignoring!\n");
555 				}
556 			}
557 			break;
558 		case RPC_AUTH_GSS:
559 			dprintk("RPC_AUTH_GSS callback secflavor "
560 				"not supported!\n");
561 			READ_BUF(8);
562 			/* gcbp_service */
563 			dummy = be32_to_cpup(p++);
564 			/* gcbp_handle_from_server */
565 			dummy = be32_to_cpup(p++);
566 			READ_BUF(dummy);
567 			p += XDR_QUADLEN(dummy);
568 			/* gcbp_handle_from_client */
569 			READ_BUF(4);
570 			dummy = be32_to_cpup(p++);
571 			READ_BUF(dummy);
572 			break;
573 		default:
574 			dprintk("Illegal callback secflavor\n");
575 			return nfserr_inval;
576 		}
577 	}
578 	DECODE_TAIL;
579 }
580 
581 static __be32 nfsd4_decode_backchannel_ctl(struct nfsd4_compoundargs *argp, struct nfsd4_backchannel_ctl *bc)
582 {
583 	DECODE_HEAD;
584 
585 	READ_BUF(4);
586 	bc->bc_cb_program = be32_to_cpup(p++);
587 	nfsd4_decode_cb_sec(argp, &bc->bc_cb_sec);
588 
589 	DECODE_TAIL;
590 }
591 
592 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
593 {
594 	DECODE_HEAD;
595 
596 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
597 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
598 	bcts->dir = be32_to_cpup(p++);
599 	/* XXX: skipping ctsa_use_conn_in_rdma_mode.  Perhaps Tom Tucker
600 	 * could help us figure out we should be using it. */
601 	DECODE_TAIL;
602 }
603 
604 static __be32
605 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
606 {
607 	DECODE_HEAD;
608 
609 	READ_BUF(4);
610 	close->cl_seqid = be32_to_cpup(p++);
611 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
612 
613 	DECODE_TAIL;
614 }
615 
616 
617 static __be32
618 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
619 {
620 	DECODE_HEAD;
621 
622 	READ_BUF(12);
623 	p = xdr_decode_hyper(p, &commit->co_offset);
624 	commit->co_count = be32_to_cpup(p++);
625 
626 	DECODE_TAIL;
627 }
628 
629 static __be32
630 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
631 {
632 	DECODE_HEAD;
633 
634 	READ_BUF(4);
635 	create->cr_type = be32_to_cpup(p++);
636 	switch (create->cr_type) {
637 	case NF4LNK:
638 		READ_BUF(4);
639 		create->cr_datalen = be32_to_cpup(p++);
640 		READ_BUF(create->cr_datalen);
641 		create->cr_data = svcxdr_dupstr(argp, p, create->cr_datalen);
642 		if (!create->cr_data)
643 			return nfserr_jukebox;
644 		break;
645 	case NF4BLK:
646 	case NF4CHR:
647 		READ_BUF(8);
648 		create->cr_specdata1 = be32_to_cpup(p++);
649 		create->cr_specdata2 = be32_to_cpup(p++);
650 		break;
651 	case NF4SOCK:
652 	case NF4FIFO:
653 	case NF4DIR:
654 	default:
655 		break;
656 	}
657 
658 	READ_BUF(4);
659 	create->cr_namelen = be32_to_cpup(p++);
660 	READ_BUF(create->cr_namelen);
661 	SAVEMEM(create->cr_name, create->cr_namelen);
662 	if ((status = check_filename(create->cr_name, create->cr_namelen)))
663 		return status;
664 
665 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
666 				    &create->cr_acl, &create->cr_label,
667 				    &current->fs->umask);
668 	if (status)
669 		goto out;
670 
671 	DECODE_TAIL;
672 }
673 
674 static inline __be32
675 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
676 {
677 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
678 }
679 
680 static inline __be32
681 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
682 {
683 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
684 }
685 
686 static __be32
687 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
688 {
689 	DECODE_HEAD;
690 
691 	READ_BUF(4);
692 	link->li_namelen = be32_to_cpup(p++);
693 	READ_BUF(link->li_namelen);
694 	SAVEMEM(link->li_name, link->li_namelen);
695 	if ((status = check_filename(link->li_name, link->li_namelen)))
696 		return status;
697 
698 	DECODE_TAIL;
699 }
700 
701 static __be32
702 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
703 {
704 	DECODE_HEAD;
705 
706 	/*
707 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
708 	*/
709 	READ_BUF(28);
710 	lock->lk_type = be32_to_cpup(p++);
711 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
712 		goto xdr_error;
713 	lock->lk_reclaim = be32_to_cpup(p++);
714 	p = xdr_decode_hyper(p, &lock->lk_offset);
715 	p = xdr_decode_hyper(p, &lock->lk_length);
716 	lock->lk_is_new = be32_to_cpup(p++);
717 
718 	if (lock->lk_is_new) {
719 		READ_BUF(4);
720 		lock->lk_new_open_seqid = be32_to_cpup(p++);
721 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
722 		if (status)
723 			return status;
724 		READ_BUF(8 + sizeof(clientid_t));
725 		lock->lk_new_lock_seqid = be32_to_cpup(p++);
726 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
727 		lock->lk_new_owner.len = be32_to_cpup(p++);
728 		READ_BUF(lock->lk_new_owner.len);
729 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
730 	} else {
731 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
732 		if (status)
733 			return status;
734 		READ_BUF(4);
735 		lock->lk_old_lock_seqid = be32_to_cpup(p++);
736 	}
737 
738 	DECODE_TAIL;
739 }
740 
741 static __be32
742 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
743 {
744 	DECODE_HEAD;
745 
746 	READ_BUF(32);
747 	lockt->lt_type = be32_to_cpup(p++);
748 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
749 		goto xdr_error;
750 	p = xdr_decode_hyper(p, &lockt->lt_offset);
751 	p = xdr_decode_hyper(p, &lockt->lt_length);
752 	COPYMEM(&lockt->lt_clientid, 8);
753 	lockt->lt_owner.len = be32_to_cpup(p++);
754 	READ_BUF(lockt->lt_owner.len);
755 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
756 
757 	DECODE_TAIL;
758 }
759 
760 static __be32
761 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
762 {
763 	DECODE_HEAD;
764 
765 	READ_BUF(8);
766 	locku->lu_type = be32_to_cpup(p++);
767 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
768 		goto xdr_error;
769 	locku->lu_seqid = be32_to_cpup(p++);
770 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
771 	if (status)
772 		return status;
773 	READ_BUF(16);
774 	p = xdr_decode_hyper(p, &locku->lu_offset);
775 	p = xdr_decode_hyper(p, &locku->lu_length);
776 
777 	DECODE_TAIL;
778 }
779 
780 static __be32
781 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
782 {
783 	DECODE_HEAD;
784 
785 	READ_BUF(4);
786 	lookup->lo_len = be32_to_cpup(p++);
787 	READ_BUF(lookup->lo_len);
788 	SAVEMEM(lookup->lo_name, lookup->lo_len);
789 	if ((status = check_filename(lookup->lo_name, lookup->lo_len)))
790 		return status;
791 
792 	DECODE_TAIL;
793 }
794 
795 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
796 {
797 	__be32 *p;
798 	u32 w;
799 
800 	READ_BUF(4);
801 	w = be32_to_cpup(p++);
802 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
803 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
804 	if (deleg_when)
805 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
806 
807 	switch (w & NFS4_SHARE_ACCESS_MASK) {
808 	case NFS4_SHARE_ACCESS_READ:
809 	case NFS4_SHARE_ACCESS_WRITE:
810 	case NFS4_SHARE_ACCESS_BOTH:
811 		break;
812 	default:
813 		return nfserr_bad_xdr;
814 	}
815 	w &= ~NFS4_SHARE_ACCESS_MASK;
816 	if (!w)
817 		return nfs_ok;
818 	if (!argp->minorversion)
819 		return nfserr_bad_xdr;
820 	switch (w & NFS4_SHARE_WANT_MASK) {
821 	case NFS4_SHARE_WANT_NO_PREFERENCE:
822 	case NFS4_SHARE_WANT_READ_DELEG:
823 	case NFS4_SHARE_WANT_WRITE_DELEG:
824 	case NFS4_SHARE_WANT_ANY_DELEG:
825 	case NFS4_SHARE_WANT_NO_DELEG:
826 	case NFS4_SHARE_WANT_CANCEL:
827 		break;
828 	default:
829 		return nfserr_bad_xdr;
830 	}
831 	w &= ~NFS4_SHARE_WANT_MASK;
832 	if (!w)
833 		return nfs_ok;
834 
835 	if (!deleg_when)	/* open_downgrade */
836 		return nfserr_inval;
837 	switch (w) {
838 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
839 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
840 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
841 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
842 		return nfs_ok;
843 	}
844 xdr_error:
845 	return nfserr_bad_xdr;
846 }
847 
848 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
849 {
850 	__be32 *p;
851 
852 	READ_BUF(4);
853 	*x = be32_to_cpup(p++);
854 	/* Note: unlinke access bits, deny bits may be zero. */
855 	if (*x & ~NFS4_SHARE_DENY_BOTH)
856 		return nfserr_bad_xdr;
857 	return nfs_ok;
858 xdr_error:
859 	return nfserr_bad_xdr;
860 }
861 
862 static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
863 {
864 	__be32 *p;
865 
866 	READ_BUF(4);
867 	o->len = be32_to_cpup(p++);
868 
869 	if (o->len == 0 || o->len > NFS4_OPAQUE_LIMIT)
870 		return nfserr_bad_xdr;
871 
872 	READ_BUF(o->len);
873 	SAVEMEM(o->data, o->len);
874 	return nfs_ok;
875 xdr_error:
876 	return nfserr_bad_xdr;
877 }
878 
879 static __be32
880 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
881 {
882 	DECODE_HEAD;
883 	u32 dummy;
884 
885 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
886 	open->op_iattr.ia_valid = 0;
887 	open->op_openowner = NULL;
888 
889 	open->op_xdr_error = 0;
890 	/* seqid, share_access, share_deny, clientid, ownerlen */
891 	READ_BUF(4);
892 	open->op_seqid = be32_to_cpup(p++);
893 	/* decode, yet ignore deleg_when until supported */
894 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
895 					   &open->op_deleg_want, &dummy);
896 	if (status)
897 		goto xdr_error;
898 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
899 	if (status)
900 		goto xdr_error;
901 	READ_BUF(sizeof(clientid_t));
902 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
903 	status = nfsd4_decode_opaque(argp, &open->op_owner);
904 	if (status)
905 		goto xdr_error;
906 	READ_BUF(4);
907 	open->op_create = be32_to_cpup(p++);
908 	switch (open->op_create) {
909 	case NFS4_OPEN_NOCREATE:
910 		break;
911 	case NFS4_OPEN_CREATE:
912 		current->fs->umask = 0;
913 		READ_BUF(4);
914 		open->op_createmode = be32_to_cpup(p++);
915 		switch (open->op_createmode) {
916 		case NFS4_CREATE_UNCHECKED:
917 		case NFS4_CREATE_GUARDED:
918 			status = nfsd4_decode_fattr(argp, open->op_bmval,
919 				&open->op_iattr, &open->op_acl, &open->op_label,
920 				&current->fs->umask);
921 			if (status)
922 				goto out;
923 			break;
924 		case NFS4_CREATE_EXCLUSIVE:
925 			READ_BUF(NFS4_VERIFIER_SIZE);
926 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
927 			break;
928 		case NFS4_CREATE_EXCLUSIVE4_1:
929 			if (argp->minorversion < 1)
930 				goto xdr_error;
931 			READ_BUF(NFS4_VERIFIER_SIZE);
932 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
933 			status = nfsd4_decode_fattr(argp, open->op_bmval,
934 				&open->op_iattr, &open->op_acl, &open->op_label,
935 				&current->fs->umask);
936 			if (status)
937 				goto out;
938 			break;
939 		default:
940 			goto xdr_error;
941 		}
942 		break;
943 	default:
944 		goto xdr_error;
945 	}
946 
947 	/* open_claim */
948 	READ_BUF(4);
949 	open->op_claim_type = be32_to_cpup(p++);
950 	switch (open->op_claim_type) {
951 	case NFS4_OPEN_CLAIM_NULL:
952 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
953 		READ_BUF(4);
954 		open->op_fname.len = be32_to_cpup(p++);
955 		READ_BUF(open->op_fname.len);
956 		SAVEMEM(open->op_fname.data, open->op_fname.len);
957 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
958 			return status;
959 		break;
960 	case NFS4_OPEN_CLAIM_PREVIOUS:
961 		READ_BUF(4);
962 		open->op_delegate_type = be32_to_cpup(p++);
963 		break;
964 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
965 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
966 		if (status)
967 			return status;
968 		READ_BUF(4);
969 		open->op_fname.len = be32_to_cpup(p++);
970 		READ_BUF(open->op_fname.len);
971 		SAVEMEM(open->op_fname.data, open->op_fname.len);
972 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
973 			return status;
974 		break;
975 	case NFS4_OPEN_CLAIM_FH:
976 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
977 		if (argp->minorversion < 1)
978 			goto xdr_error;
979 		/* void */
980 		break;
981 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
982 		if (argp->minorversion < 1)
983 			goto xdr_error;
984 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
985 		if (status)
986 			return status;
987 		break;
988 	default:
989 		goto xdr_error;
990 	}
991 
992 	DECODE_TAIL;
993 }
994 
995 static __be32
996 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
997 {
998 	DECODE_HEAD;
999 
1000 	if (argp->minorversion >= 1)
1001 		return nfserr_notsupp;
1002 
1003 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
1004 	if (status)
1005 		return status;
1006 	READ_BUF(4);
1007 	open_conf->oc_seqid = be32_to_cpup(p++);
1008 
1009 	DECODE_TAIL;
1010 }
1011 
1012 static __be32
1013 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
1014 {
1015 	DECODE_HEAD;
1016 
1017 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
1018 	if (status)
1019 		return status;
1020 	READ_BUF(4);
1021 	open_down->od_seqid = be32_to_cpup(p++);
1022 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
1023 					   &open_down->od_deleg_want, NULL);
1024 	if (status)
1025 		return status;
1026 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
1027 	if (status)
1028 		return status;
1029 	DECODE_TAIL;
1030 }
1031 
1032 static __be32
1033 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
1034 {
1035 	DECODE_HEAD;
1036 
1037 	READ_BUF(4);
1038 	putfh->pf_fhlen = be32_to_cpup(p++);
1039 	if (putfh->pf_fhlen > NFS4_FHSIZE)
1040 		goto xdr_error;
1041 	READ_BUF(putfh->pf_fhlen);
1042 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
1043 
1044 	DECODE_TAIL;
1045 }
1046 
1047 static __be32
1048 nfsd4_decode_putpubfh(struct nfsd4_compoundargs *argp, void *p)
1049 {
1050 	if (argp->minorversion == 0)
1051 		return nfs_ok;
1052 	return nfserr_notsupp;
1053 }
1054 
1055 static __be32
1056 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
1057 {
1058 	DECODE_HEAD;
1059 
1060 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
1061 	if (status)
1062 		return status;
1063 	READ_BUF(12);
1064 	p = xdr_decode_hyper(p, &read->rd_offset);
1065 	read->rd_length = be32_to_cpup(p++);
1066 
1067 	DECODE_TAIL;
1068 }
1069 
1070 static __be32
1071 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
1072 {
1073 	DECODE_HEAD;
1074 
1075 	READ_BUF(24);
1076 	p = xdr_decode_hyper(p, &readdir->rd_cookie);
1077 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
1078 	readdir->rd_dircount = be32_to_cpup(p++);
1079 	readdir->rd_maxcount = be32_to_cpup(p++);
1080 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
1081 		goto out;
1082 
1083 	DECODE_TAIL;
1084 }
1085 
1086 static __be32
1087 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
1088 {
1089 	DECODE_HEAD;
1090 
1091 	READ_BUF(4);
1092 	remove->rm_namelen = be32_to_cpup(p++);
1093 	READ_BUF(remove->rm_namelen);
1094 	SAVEMEM(remove->rm_name, remove->rm_namelen);
1095 	if ((status = check_filename(remove->rm_name, remove->rm_namelen)))
1096 		return status;
1097 
1098 	DECODE_TAIL;
1099 }
1100 
1101 static __be32
1102 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
1103 {
1104 	DECODE_HEAD;
1105 
1106 	READ_BUF(4);
1107 	rename->rn_snamelen = be32_to_cpup(p++);
1108 	READ_BUF(rename->rn_snamelen);
1109 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1110 	READ_BUF(4);
1111 	rename->rn_tnamelen = be32_to_cpup(p++);
1112 	READ_BUF(rename->rn_tnamelen);
1113 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1114 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1115 		return status;
1116 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1117 		return status;
1118 
1119 	DECODE_TAIL;
1120 }
1121 
1122 static __be32
1123 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1124 {
1125 	DECODE_HEAD;
1126 
1127 	if (argp->minorversion >= 1)
1128 		return nfserr_notsupp;
1129 
1130 	READ_BUF(sizeof(clientid_t));
1131 	COPYMEM(clientid, sizeof(clientid_t));
1132 
1133 	DECODE_TAIL;
1134 }
1135 
1136 static __be32
1137 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1138 		     struct nfsd4_secinfo *secinfo)
1139 {
1140 	DECODE_HEAD;
1141 
1142 	READ_BUF(4);
1143 	secinfo->si_namelen = be32_to_cpup(p++);
1144 	READ_BUF(secinfo->si_namelen);
1145 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1146 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1147 	if (status)
1148 		return status;
1149 	DECODE_TAIL;
1150 }
1151 
1152 static __be32
1153 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1154 		     struct nfsd4_secinfo_no_name *sin)
1155 {
1156 	DECODE_HEAD;
1157 
1158 	READ_BUF(4);
1159 	sin->sin_style = be32_to_cpup(p++);
1160 	DECODE_TAIL;
1161 }
1162 
1163 static __be32
1164 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1165 {
1166 	__be32 status;
1167 
1168 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1169 	if (status)
1170 		return status;
1171 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1172 				  &setattr->sa_acl, &setattr->sa_label, NULL);
1173 }
1174 
1175 static __be32
1176 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1177 {
1178 	DECODE_HEAD;
1179 
1180 	if (argp->minorversion >= 1)
1181 		return nfserr_notsupp;
1182 
1183 	READ_BUF(NFS4_VERIFIER_SIZE);
1184 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1185 
1186 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1187 	if (status)
1188 		return nfserr_bad_xdr;
1189 	READ_BUF(8);
1190 	setclientid->se_callback_prog = be32_to_cpup(p++);
1191 	setclientid->se_callback_netid_len = be32_to_cpup(p++);
1192 	READ_BUF(setclientid->se_callback_netid_len);
1193 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1194 	READ_BUF(4);
1195 	setclientid->se_callback_addr_len = be32_to_cpup(p++);
1196 
1197 	READ_BUF(setclientid->se_callback_addr_len);
1198 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1199 	READ_BUF(4);
1200 	setclientid->se_callback_ident = be32_to_cpup(p++);
1201 
1202 	DECODE_TAIL;
1203 }
1204 
1205 static __be32
1206 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1207 {
1208 	DECODE_HEAD;
1209 
1210 	if (argp->minorversion >= 1)
1211 		return nfserr_notsupp;
1212 
1213 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1214 	COPYMEM(&scd_c->sc_clientid, 8);
1215 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1216 
1217 	DECODE_TAIL;
1218 }
1219 
1220 /* Also used for NVERIFY */
1221 static __be32
1222 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1223 {
1224 	DECODE_HEAD;
1225 
1226 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1227 		goto out;
1228 
1229 	/* For convenience's sake, we compare raw xdr'd attributes in
1230 	 * nfsd4_proc_verify */
1231 
1232 	READ_BUF(4);
1233 	verify->ve_attrlen = be32_to_cpup(p++);
1234 	READ_BUF(verify->ve_attrlen);
1235 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1236 
1237 	DECODE_TAIL;
1238 }
1239 
1240 static __be32
1241 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1242 {
1243 	int avail;
1244 	int len;
1245 	DECODE_HEAD;
1246 
1247 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1248 	if (status)
1249 		return status;
1250 	READ_BUF(16);
1251 	p = xdr_decode_hyper(p, &write->wr_offset);
1252 	write->wr_stable_how = be32_to_cpup(p++);
1253 	if (write->wr_stable_how > NFS_FILE_SYNC)
1254 		goto xdr_error;
1255 	write->wr_buflen = be32_to_cpup(p++);
1256 
1257 	/* Sorry .. no magic macros for this.. *
1258 	 * READ_BUF(write->wr_buflen);
1259 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1260 	 */
1261 	avail = (char*)argp->end - (char*)argp->p;
1262 	if (avail + argp->pagelen < write->wr_buflen) {
1263 		dprintk("NFSD: xdr error (%s:%d)\n",
1264 				__FILE__, __LINE__);
1265 		goto xdr_error;
1266 	}
1267 	write->wr_head.iov_base = p;
1268 	write->wr_head.iov_len = avail;
1269 	write->wr_pagelist = argp->pagelist;
1270 
1271 	len = XDR_QUADLEN(write->wr_buflen) << 2;
1272 	if (len >= avail) {
1273 		int pages;
1274 
1275 		len -= avail;
1276 
1277 		pages = len >> PAGE_SHIFT;
1278 		argp->pagelist += pages;
1279 		argp->pagelen -= pages * PAGE_SIZE;
1280 		len -= pages * PAGE_SIZE;
1281 
1282 		next_decode_page(argp);
1283 	}
1284 	argp->p += XDR_QUADLEN(len);
1285 
1286 	DECODE_TAIL;
1287 }
1288 
1289 static __be32
1290 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1291 {
1292 	DECODE_HEAD;
1293 
1294 	if (argp->minorversion >= 1)
1295 		return nfserr_notsupp;
1296 
1297 	READ_BUF(12);
1298 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1299 	rlockowner->rl_owner.len = be32_to_cpup(p++);
1300 	READ_BUF(rlockowner->rl_owner.len);
1301 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1302 
1303 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1304 		return nfserr_inval;
1305 	DECODE_TAIL;
1306 }
1307 
1308 static __be32
1309 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1310 			 struct nfsd4_exchange_id *exid)
1311 {
1312 	int dummy, tmp;
1313 	DECODE_HEAD;
1314 
1315 	READ_BUF(NFS4_VERIFIER_SIZE);
1316 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1317 
1318 	status = nfsd4_decode_opaque(argp, &exid->clname);
1319 	if (status)
1320 		return nfserr_bad_xdr;
1321 
1322 	READ_BUF(4);
1323 	exid->flags = be32_to_cpup(p++);
1324 
1325 	/* Ignore state_protect4_a */
1326 	READ_BUF(4);
1327 	exid->spa_how = be32_to_cpup(p++);
1328 	switch (exid->spa_how) {
1329 	case SP4_NONE:
1330 		break;
1331 	case SP4_MACH_CRED:
1332 		/* spo_must_enforce */
1333 		status = nfsd4_decode_bitmap(argp,
1334 					exid->spo_must_enforce);
1335 		if (status)
1336 			goto out;
1337 		/* spo_must_allow */
1338 		status = nfsd4_decode_bitmap(argp, exid->spo_must_allow);
1339 		if (status)
1340 			goto out;
1341 		break;
1342 	case SP4_SSV:
1343 		/* ssp_ops */
1344 		READ_BUF(4);
1345 		dummy = be32_to_cpup(p++);
1346 		READ_BUF(dummy * 4);
1347 		p += dummy;
1348 
1349 		READ_BUF(4);
1350 		dummy = be32_to_cpup(p++);
1351 		READ_BUF(dummy * 4);
1352 		p += dummy;
1353 
1354 		/* ssp_hash_algs<> */
1355 		READ_BUF(4);
1356 		tmp = be32_to_cpup(p++);
1357 		while (tmp--) {
1358 			READ_BUF(4);
1359 			dummy = be32_to_cpup(p++);
1360 			READ_BUF(dummy);
1361 			p += XDR_QUADLEN(dummy);
1362 		}
1363 
1364 		/* ssp_encr_algs<> */
1365 		READ_BUF(4);
1366 		tmp = be32_to_cpup(p++);
1367 		while (tmp--) {
1368 			READ_BUF(4);
1369 			dummy = be32_to_cpup(p++);
1370 			READ_BUF(dummy);
1371 			p += XDR_QUADLEN(dummy);
1372 		}
1373 
1374 		/* ssp_window and ssp_num_gss_handles */
1375 		READ_BUF(8);
1376 		dummy = be32_to_cpup(p++);
1377 		dummy = be32_to_cpup(p++);
1378 		break;
1379 	default:
1380 		goto xdr_error;
1381 	}
1382 
1383 	/* Ignore Implementation ID */
1384 	READ_BUF(4);    /* nfs_impl_id4 array length */
1385 	dummy = be32_to_cpup(p++);
1386 
1387 	if (dummy > 1)
1388 		goto xdr_error;
1389 
1390 	if (dummy == 1) {
1391 		/* nii_domain */
1392 		READ_BUF(4);
1393 		dummy = be32_to_cpup(p++);
1394 		READ_BUF(dummy);
1395 		p += XDR_QUADLEN(dummy);
1396 
1397 		/* nii_name */
1398 		READ_BUF(4);
1399 		dummy = be32_to_cpup(p++);
1400 		READ_BUF(dummy);
1401 		p += XDR_QUADLEN(dummy);
1402 
1403 		/* nii_date */
1404 		READ_BUF(12);
1405 		p += 3;
1406 	}
1407 	DECODE_TAIL;
1408 }
1409 
1410 static __be32
1411 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1412 			    struct nfsd4_create_session *sess)
1413 {
1414 	DECODE_HEAD;
1415 	u32 dummy;
1416 
1417 	READ_BUF(16);
1418 	COPYMEM(&sess->clientid, 8);
1419 	sess->seqid = be32_to_cpup(p++);
1420 	sess->flags = be32_to_cpup(p++);
1421 
1422 	/* Fore channel attrs */
1423 	READ_BUF(28);
1424 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1425 	sess->fore_channel.maxreq_sz = be32_to_cpup(p++);
1426 	sess->fore_channel.maxresp_sz = be32_to_cpup(p++);
1427 	sess->fore_channel.maxresp_cached = be32_to_cpup(p++);
1428 	sess->fore_channel.maxops = be32_to_cpup(p++);
1429 	sess->fore_channel.maxreqs = be32_to_cpup(p++);
1430 	sess->fore_channel.nr_rdma_attrs = be32_to_cpup(p++);
1431 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1432 		READ_BUF(4);
1433 		sess->fore_channel.rdma_attrs = be32_to_cpup(p++);
1434 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1435 		dprintk("Too many fore channel attr bitmaps!\n");
1436 		goto xdr_error;
1437 	}
1438 
1439 	/* Back channel attrs */
1440 	READ_BUF(28);
1441 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1442 	sess->back_channel.maxreq_sz = be32_to_cpup(p++);
1443 	sess->back_channel.maxresp_sz = be32_to_cpup(p++);
1444 	sess->back_channel.maxresp_cached = be32_to_cpup(p++);
1445 	sess->back_channel.maxops = be32_to_cpup(p++);
1446 	sess->back_channel.maxreqs = be32_to_cpup(p++);
1447 	sess->back_channel.nr_rdma_attrs = be32_to_cpup(p++);
1448 	if (sess->back_channel.nr_rdma_attrs == 1) {
1449 		READ_BUF(4);
1450 		sess->back_channel.rdma_attrs = be32_to_cpup(p++);
1451 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1452 		dprintk("Too many back channel attr bitmaps!\n");
1453 		goto xdr_error;
1454 	}
1455 
1456 	READ_BUF(4);
1457 	sess->callback_prog = be32_to_cpup(p++);
1458 	nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1459 	DECODE_TAIL;
1460 }
1461 
1462 static __be32
1463 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1464 			     struct nfsd4_destroy_session *destroy_session)
1465 {
1466 	DECODE_HEAD;
1467 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1468 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1469 
1470 	DECODE_TAIL;
1471 }
1472 
1473 static __be32
1474 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1475 			  struct nfsd4_free_stateid *free_stateid)
1476 {
1477 	DECODE_HEAD;
1478 
1479 	READ_BUF(sizeof(stateid_t));
1480 	free_stateid->fr_stateid.si_generation = be32_to_cpup(p++);
1481 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1482 
1483 	DECODE_TAIL;
1484 }
1485 
1486 static __be32
1487 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1488 		      struct nfsd4_sequence *seq)
1489 {
1490 	DECODE_HEAD;
1491 
1492 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1493 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1494 	seq->seqid = be32_to_cpup(p++);
1495 	seq->slotid = be32_to_cpup(p++);
1496 	seq->maxslots = be32_to_cpup(p++);
1497 	seq->cachethis = be32_to_cpup(p++);
1498 
1499 	DECODE_TAIL;
1500 }
1501 
1502 static __be32
1503 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1504 {
1505 	int i;
1506 	__be32 *p, status;
1507 	struct nfsd4_test_stateid_id *stateid;
1508 
1509 	READ_BUF(4);
1510 	test_stateid->ts_num_ids = ntohl(*p++);
1511 
1512 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1513 
1514 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1515 		stateid = svcxdr_tmpalloc(argp, sizeof(*stateid));
1516 		if (!stateid) {
1517 			status = nfserrno(-ENOMEM);
1518 			goto out;
1519 		}
1520 
1521 		INIT_LIST_HEAD(&stateid->ts_id_list);
1522 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1523 
1524 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1525 		if (status)
1526 			goto out;
1527 	}
1528 
1529 	status = 0;
1530 out:
1531 	return status;
1532 xdr_error:
1533 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1534 	status = nfserr_bad_xdr;
1535 	goto out;
1536 }
1537 
1538 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1539 {
1540 	DECODE_HEAD;
1541 
1542 	READ_BUF(8);
1543 	COPYMEM(&dc->clientid, 8);
1544 
1545 	DECODE_TAIL;
1546 }
1547 
1548 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1549 {
1550 	DECODE_HEAD;
1551 
1552 	READ_BUF(4);
1553 	rc->rca_one_fs = be32_to_cpup(p++);
1554 
1555 	DECODE_TAIL;
1556 }
1557 
1558 #ifdef CONFIG_NFSD_PNFS
1559 static __be32
1560 nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp,
1561 		struct nfsd4_getdeviceinfo *gdev)
1562 {
1563 	DECODE_HEAD;
1564 	u32 num, i;
1565 
1566 	READ_BUF(sizeof(struct nfsd4_deviceid) + 3 * 4);
1567 	COPYMEM(&gdev->gd_devid, sizeof(struct nfsd4_deviceid));
1568 	gdev->gd_layout_type = be32_to_cpup(p++);
1569 	gdev->gd_maxcount = be32_to_cpup(p++);
1570 	num = be32_to_cpup(p++);
1571 	if (num) {
1572 		READ_BUF(4 * num);
1573 		gdev->gd_notify_types = be32_to_cpup(p++);
1574 		for (i = 1; i < num; i++) {
1575 			if (be32_to_cpup(p++)) {
1576 				status = nfserr_inval;
1577 				goto out;
1578 			}
1579 		}
1580 	}
1581 	DECODE_TAIL;
1582 }
1583 
1584 static __be32
1585 nfsd4_decode_layoutget(struct nfsd4_compoundargs *argp,
1586 		struct nfsd4_layoutget *lgp)
1587 {
1588 	DECODE_HEAD;
1589 
1590 	READ_BUF(36);
1591 	lgp->lg_signal = be32_to_cpup(p++);
1592 	lgp->lg_layout_type = be32_to_cpup(p++);
1593 	lgp->lg_seg.iomode = be32_to_cpup(p++);
1594 	p = xdr_decode_hyper(p, &lgp->lg_seg.offset);
1595 	p = xdr_decode_hyper(p, &lgp->lg_seg.length);
1596 	p = xdr_decode_hyper(p, &lgp->lg_minlength);
1597 
1598 	status = nfsd4_decode_stateid(argp, &lgp->lg_sid);
1599 	if (status)
1600 		return status;
1601 
1602 	READ_BUF(4);
1603 	lgp->lg_maxcount = be32_to_cpup(p++);
1604 
1605 	DECODE_TAIL;
1606 }
1607 
1608 static __be32
1609 nfsd4_decode_layoutcommit(struct nfsd4_compoundargs *argp,
1610 		struct nfsd4_layoutcommit *lcp)
1611 {
1612 	DECODE_HEAD;
1613 	u32 timechange;
1614 
1615 	READ_BUF(20);
1616 	p = xdr_decode_hyper(p, &lcp->lc_seg.offset);
1617 	p = xdr_decode_hyper(p, &lcp->lc_seg.length);
1618 	lcp->lc_reclaim = be32_to_cpup(p++);
1619 
1620 	status = nfsd4_decode_stateid(argp, &lcp->lc_sid);
1621 	if (status)
1622 		return status;
1623 
1624 	READ_BUF(4);
1625 	lcp->lc_newoffset = be32_to_cpup(p++);
1626 	if (lcp->lc_newoffset) {
1627 		READ_BUF(8);
1628 		p = xdr_decode_hyper(p, &lcp->lc_last_wr);
1629 	} else
1630 		lcp->lc_last_wr = 0;
1631 	READ_BUF(4);
1632 	timechange = be32_to_cpup(p++);
1633 	if (timechange) {
1634 		status = nfsd4_decode_time(argp, &lcp->lc_mtime);
1635 		if (status)
1636 			return status;
1637 	} else {
1638 		lcp->lc_mtime.tv_nsec = UTIME_NOW;
1639 	}
1640 	READ_BUF(8);
1641 	lcp->lc_layout_type = be32_to_cpup(p++);
1642 
1643 	/*
1644 	 * Save the layout update in XDR format and let the layout driver deal
1645 	 * with it later.
1646 	 */
1647 	lcp->lc_up_len = be32_to_cpup(p++);
1648 	if (lcp->lc_up_len > 0) {
1649 		READ_BUF(lcp->lc_up_len);
1650 		READMEM(lcp->lc_up_layout, lcp->lc_up_len);
1651 	}
1652 
1653 	DECODE_TAIL;
1654 }
1655 
1656 static __be32
1657 nfsd4_decode_layoutreturn(struct nfsd4_compoundargs *argp,
1658 		struct nfsd4_layoutreturn *lrp)
1659 {
1660 	DECODE_HEAD;
1661 
1662 	READ_BUF(16);
1663 	lrp->lr_reclaim = be32_to_cpup(p++);
1664 	lrp->lr_layout_type = be32_to_cpup(p++);
1665 	lrp->lr_seg.iomode = be32_to_cpup(p++);
1666 	lrp->lr_return_type = be32_to_cpup(p++);
1667 	if (lrp->lr_return_type == RETURN_FILE) {
1668 		READ_BUF(16);
1669 		p = xdr_decode_hyper(p, &lrp->lr_seg.offset);
1670 		p = xdr_decode_hyper(p, &lrp->lr_seg.length);
1671 
1672 		status = nfsd4_decode_stateid(argp, &lrp->lr_sid);
1673 		if (status)
1674 			return status;
1675 
1676 		READ_BUF(4);
1677 		lrp->lrf_body_len = be32_to_cpup(p++);
1678 		if (lrp->lrf_body_len > 0) {
1679 			READ_BUF(lrp->lrf_body_len);
1680 			READMEM(lrp->lrf_body, lrp->lrf_body_len);
1681 		}
1682 	} else {
1683 		lrp->lr_seg.offset = 0;
1684 		lrp->lr_seg.length = NFS4_MAX_UINT64;
1685 	}
1686 
1687 	DECODE_TAIL;
1688 }
1689 #endif /* CONFIG_NFSD_PNFS */
1690 
1691 static __be32
1692 nfsd4_decode_fallocate(struct nfsd4_compoundargs *argp,
1693 		       struct nfsd4_fallocate *fallocate)
1694 {
1695 	DECODE_HEAD;
1696 
1697 	status = nfsd4_decode_stateid(argp, &fallocate->falloc_stateid);
1698 	if (status)
1699 		return status;
1700 
1701 	READ_BUF(16);
1702 	p = xdr_decode_hyper(p, &fallocate->falloc_offset);
1703 	xdr_decode_hyper(p, &fallocate->falloc_length);
1704 
1705 	DECODE_TAIL;
1706 }
1707 
1708 static __be32
1709 nfsd4_decode_clone(struct nfsd4_compoundargs *argp, struct nfsd4_clone *clone)
1710 {
1711 	DECODE_HEAD;
1712 
1713 	status = nfsd4_decode_stateid(argp, &clone->cl_src_stateid);
1714 	if (status)
1715 		return status;
1716 	status = nfsd4_decode_stateid(argp, &clone->cl_dst_stateid);
1717 	if (status)
1718 		return status;
1719 
1720 	READ_BUF(8 + 8 + 8);
1721 	p = xdr_decode_hyper(p, &clone->cl_src_pos);
1722 	p = xdr_decode_hyper(p, &clone->cl_dst_pos);
1723 	p = xdr_decode_hyper(p, &clone->cl_count);
1724 	DECODE_TAIL;
1725 }
1726 
1727 static __be32
1728 nfsd4_decode_copy(struct nfsd4_compoundargs *argp, struct nfsd4_copy *copy)
1729 {
1730 	DECODE_HEAD;
1731 	unsigned int tmp;
1732 
1733 	status = nfsd4_decode_stateid(argp, &copy->cp_src_stateid);
1734 	if (status)
1735 		return status;
1736 	status = nfsd4_decode_stateid(argp, &copy->cp_dst_stateid);
1737 	if (status)
1738 		return status;
1739 
1740 	READ_BUF(8 + 8 + 8 + 4 + 4 + 4);
1741 	p = xdr_decode_hyper(p, &copy->cp_src_pos);
1742 	p = xdr_decode_hyper(p, &copy->cp_dst_pos);
1743 	p = xdr_decode_hyper(p, &copy->cp_count);
1744 	copy->cp_consecutive = be32_to_cpup(p++);
1745 	copy->cp_synchronous = be32_to_cpup(p++);
1746 	tmp = be32_to_cpup(p); /* Source server list not supported */
1747 
1748 	DECODE_TAIL;
1749 }
1750 
1751 static __be32
1752 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
1753 {
1754 	DECODE_HEAD;
1755 
1756 	status = nfsd4_decode_stateid(argp, &seek->seek_stateid);
1757 	if (status)
1758 		return status;
1759 
1760 	READ_BUF(8 + 4);
1761 	p = xdr_decode_hyper(p, &seek->seek_offset);
1762 	seek->seek_whence = be32_to_cpup(p);
1763 
1764 	DECODE_TAIL;
1765 }
1766 
1767 static __be32
1768 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1769 {
1770 	return nfs_ok;
1771 }
1772 
1773 static __be32
1774 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1775 {
1776 	return nfserr_notsupp;
1777 }
1778 
1779 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1780 
1781 static nfsd4_dec nfsd4_dec_ops[] = {
1782 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1783 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1784 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1785 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1786 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1787 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1788 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1789 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1790 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1791 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1792 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1793 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1794 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1795 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1796 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1797 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1798 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1799 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1800 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1801 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1802 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_putpubfh,
1803 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1804 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1805 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1806 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1807 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1808 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1809 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1810 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1811 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1812 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1813 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1814 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1815 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1816 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1817 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1818 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1819 
1820 	/* new operations for NFSv4.1 */
1821 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_backchannel_ctl,
1822 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1823 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1824 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1825 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1826 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
1827 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1828 #ifdef CONFIG_NFSD_PNFS
1829 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_getdeviceinfo,
1830 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1831 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_layoutcommit,
1832 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_layoutget,
1833 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_layoutreturn,
1834 #else
1835 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1836 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1837 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1838 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1839 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1840 #endif
1841 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1842 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1843 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1844 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
1845 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1846 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
1847 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1848 
1849 	/* new operations for NFSv4.2 */
1850 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1851 	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_copy,
1852 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
1853 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1854 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1855 	[OP_LAYOUTERROR]	= (nfsd4_dec)nfsd4_decode_notsupp,
1856 	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1857 	[OP_OFFLOAD_CANCEL]	= (nfsd4_dec)nfsd4_decode_notsupp,
1858 	[OP_OFFLOAD_STATUS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1859 	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_notsupp,
1860 	[OP_SEEK]		= (nfsd4_dec)nfsd4_decode_seek,
1861 	[OP_WRITE_SAME]		= (nfsd4_dec)nfsd4_decode_notsupp,
1862 	[OP_CLONE]		= (nfsd4_dec)nfsd4_decode_clone,
1863 };
1864 
1865 static inline bool
1866 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
1867 {
1868 	if (op->opnum < FIRST_NFS4_OP)
1869 		return false;
1870 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
1871 		return false;
1872 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
1873 		return false;
1874 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
1875 		return false;
1876 	return true;
1877 }
1878 
1879 static __be32
1880 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1881 {
1882 	DECODE_HEAD;
1883 	struct nfsd4_op *op;
1884 	bool cachethis = false;
1885 	int auth_slack= argp->rqstp->rq_auth_slack;
1886 	int max_reply = auth_slack + 8; /* opcnt, status */
1887 	int readcount = 0;
1888 	int readbytes = 0;
1889 	int i;
1890 
1891 	READ_BUF(4);
1892 	argp->taglen = be32_to_cpup(p++);
1893 	READ_BUF(argp->taglen);
1894 	SAVEMEM(argp->tag, argp->taglen);
1895 	READ_BUF(8);
1896 	argp->minorversion = be32_to_cpup(p++);
1897 	argp->opcnt = be32_to_cpup(p++);
1898 	max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
1899 
1900 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1901 		goto xdr_error;
1902 	if (argp->opcnt > 100)
1903 		goto xdr_error;
1904 
1905 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1906 		argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1907 		if (!argp->ops) {
1908 			argp->ops = argp->iops;
1909 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1910 			goto xdr_error;
1911 		}
1912 	}
1913 
1914 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
1915 		argp->opcnt = 0;
1916 
1917 	for (i = 0; i < argp->opcnt; i++) {
1918 		op = &argp->ops[i];
1919 		op->replay = NULL;
1920 
1921 		READ_BUF(4);
1922 		op->opnum = be32_to_cpup(p++);
1923 
1924 		if (nfsd4_opnum_in_range(argp, op))
1925 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
1926 		else {
1927 			op->opnum = OP_ILLEGAL;
1928 			op->status = nfserr_op_illegal;
1929 		}
1930 		/*
1931 		 * We'll try to cache the result in the DRC if any one
1932 		 * op in the compound wants to be cached:
1933 		 */
1934 		cachethis |= nfsd4_cache_this_op(op);
1935 
1936 		if (op->opnum == OP_READ) {
1937 			readcount++;
1938 			readbytes += nfsd4_max_reply(argp->rqstp, op);
1939 		} else
1940 			max_reply += nfsd4_max_reply(argp->rqstp, op);
1941 		/*
1942 		 * OP_LOCK and OP_LOCKT may return a conflicting lock.
1943 		 * (Special case because it will just skip encoding this
1944 		 * if it runs out of xdr buffer space, and it is the only
1945 		 * operation that behaves this way.)
1946 		 */
1947 		if (op->opnum == OP_LOCK || op->opnum == OP_LOCKT)
1948 			max_reply += NFS4_OPAQUE_LIMIT;
1949 
1950 		if (op->status) {
1951 			argp->opcnt = i+1;
1952 			break;
1953 		}
1954 	}
1955 	/* Sessions make the DRC unnecessary: */
1956 	if (argp->minorversion)
1957 		cachethis = false;
1958 	svc_reserve(argp->rqstp, max_reply + readbytes);
1959 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1960 
1961 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
1962 		clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
1963 
1964 	DECODE_TAIL;
1965 }
1966 
1967 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode,
1968 			     struct svc_export *exp)
1969 {
1970 	if (exp->ex_flags & NFSEXP_V4ROOT) {
1971 		*p++ = cpu_to_be32(convert_to_wallclock(exp->cd->flush_time));
1972 		*p++ = 0;
1973 	} else if (IS_I_VERSION(inode)) {
1974 		p = xdr_encode_hyper(p, nfsd4_change_attribute(inode));
1975 	} else {
1976 		*p++ = cpu_to_be32(stat->ctime.tv_sec);
1977 		*p++ = cpu_to_be32(stat->ctime.tv_nsec);
1978 	}
1979 	return p;
1980 }
1981 
1982 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
1983 {
1984 	*p++ = cpu_to_be32(c->atomic);
1985 	if (c->change_supported) {
1986 		p = xdr_encode_hyper(p, c->before_change);
1987 		p = xdr_encode_hyper(p, c->after_change);
1988 	} else {
1989 		*p++ = cpu_to_be32(c->before_ctime_sec);
1990 		*p++ = cpu_to_be32(c->before_ctime_nsec);
1991 		*p++ = cpu_to_be32(c->after_ctime_sec);
1992 		*p++ = cpu_to_be32(c->after_ctime_nsec);
1993 	}
1994 	return p;
1995 }
1996 
1997 /* Encode as an array of strings the string given with components
1998  * separated @sep, escaped with esc_enter and esc_exit.
1999  */
2000 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
2001 					  char *components, char esc_enter,
2002 					  char esc_exit)
2003 {
2004 	__be32 *p;
2005 	__be32 pathlen;
2006 	int pathlen_offset;
2007 	int strlen, count=0;
2008 	char *str, *end, *next;
2009 
2010 	dprintk("nfsd4_encode_components(%s)\n", components);
2011 
2012 	pathlen_offset = xdr->buf->len;
2013 	p = xdr_reserve_space(xdr, 4);
2014 	if (!p)
2015 		return nfserr_resource;
2016 	p++; /* We will fill this in with @count later */
2017 
2018 	end = str = components;
2019 	while (*end) {
2020 		bool found_esc = false;
2021 
2022 		/* try to parse as esc_start, ..., esc_end, sep */
2023 		if (*str == esc_enter) {
2024 			for (; *end && (*end != esc_exit); end++)
2025 				/* find esc_exit or end of string */;
2026 			next = end + 1;
2027 			if (*end && (!*next || *next == sep)) {
2028 				str++;
2029 				found_esc = true;
2030 			}
2031 		}
2032 
2033 		if (!found_esc)
2034 			for (; *end && (*end != sep); end++)
2035 				/* find sep or end of string */;
2036 
2037 		strlen = end - str;
2038 		if (strlen) {
2039 			p = xdr_reserve_space(xdr, strlen + 4);
2040 			if (!p)
2041 				return nfserr_resource;
2042 			p = xdr_encode_opaque(p, str, strlen);
2043 			count++;
2044 		}
2045 		else
2046 			end++;
2047 		if (found_esc)
2048 			end = next;
2049 
2050 		str = end;
2051 	}
2052 	pathlen = htonl(count);
2053 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
2054 	return 0;
2055 }
2056 
2057 /* Encode as an array of strings the string given with components
2058  * separated @sep.
2059  */
2060 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
2061 				      char *components)
2062 {
2063 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
2064 }
2065 
2066 /*
2067  * encode a location element of a fs_locations structure
2068  */
2069 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
2070 					struct nfsd4_fs_location *location)
2071 {
2072 	__be32 status;
2073 
2074 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
2075 						'[', ']');
2076 	if (status)
2077 		return status;
2078 	status = nfsd4_encode_components(xdr, '/', location->path);
2079 	if (status)
2080 		return status;
2081 	return 0;
2082 }
2083 
2084 /*
2085  * Encode a path in RFC3530 'pathname4' format
2086  */
2087 static __be32 nfsd4_encode_path(struct xdr_stream *xdr,
2088 				const struct path *root,
2089 				const struct path *path)
2090 {
2091 	struct path cur = *path;
2092 	__be32 *p;
2093 	struct dentry **components = NULL;
2094 	unsigned int ncomponents = 0;
2095 	__be32 err = nfserr_jukebox;
2096 
2097 	dprintk("nfsd4_encode_components(");
2098 
2099 	path_get(&cur);
2100 	/* First walk the path up to the nfsd root, and store the
2101 	 * dentries/path components in an array.
2102 	 */
2103 	for (;;) {
2104 		if (path_equal(&cur, root))
2105 			break;
2106 		if (cur.dentry == cur.mnt->mnt_root) {
2107 			if (follow_up(&cur))
2108 				continue;
2109 			goto out_free;
2110 		}
2111 		if ((ncomponents & 15) == 0) {
2112 			struct dentry **new;
2113 			new = krealloc(components,
2114 					sizeof(*new) * (ncomponents + 16),
2115 					GFP_KERNEL);
2116 			if (!new)
2117 				goto out_free;
2118 			components = new;
2119 		}
2120 		components[ncomponents++] = cur.dentry;
2121 		cur.dentry = dget_parent(cur.dentry);
2122 	}
2123 	err = nfserr_resource;
2124 	p = xdr_reserve_space(xdr, 4);
2125 	if (!p)
2126 		goto out_free;
2127 	*p++ = cpu_to_be32(ncomponents);
2128 
2129 	while (ncomponents) {
2130 		struct dentry *dentry = components[ncomponents - 1];
2131 		unsigned int len;
2132 
2133 		spin_lock(&dentry->d_lock);
2134 		len = dentry->d_name.len;
2135 		p = xdr_reserve_space(xdr, len + 4);
2136 		if (!p) {
2137 			spin_unlock(&dentry->d_lock);
2138 			goto out_free;
2139 		}
2140 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
2141 		dprintk("/%pd", dentry);
2142 		spin_unlock(&dentry->d_lock);
2143 		dput(dentry);
2144 		ncomponents--;
2145 	}
2146 
2147 	err = 0;
2148 out_free:
2149 	dprintk(")\n");
2150 	while (ncomponents)
2151 		dput(components[--ncomponents]);
2152 	kfree(components);
2153 	path_put(&cur);
2154 	return err;
2155 }
2156 
2157 static __be32 nfsd4_encode_fsloc_fsroot(struct xdr_stream *xdr,
2158 			struct svc_rqst *rqstp, const struct path *path)
2159 {
2160 	struct svc_export *exp_ps;
2161 	__be32 res;
2162 
2163 	exp_ps = rqst_find_fsidzero_export(rqstp);
2164 	if (IS_ERR(exp_ps))
2165 		return nfserrno(PTR_ERR(exp_ps));
2166 	res = nfsd4_encode_path(xdr, &exp_ps->ex_path, path);
2167 	exp_put(exp_ps);
2168 	return res;
2169 }
2170 
2171 /*
2172  *  encode a fs_locations structure
2173  */
2174 static __be32 nfsd4_encode_fs_locations(struct xdr_stream *xdr,
2175 			struct svc_rqst *rqstp, struct svc_export *exp)
2176 {
2177 	__be32 status;
2178 	int i;
2179 	__be32 *p;
2180 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
2181 
2182 	status = nfsd4_encode_fsloc_fsroot(xdr, rqstp, &exp->ex_path);
2183 	if (status)
2184 		return status;
2185 	p = xdr_reserve_space(xdr, 4);
2186 	if (!p)
2187 		return nfserr_resource;
2188 	*p++ = cpu_to_be32(fslocs->locations_count);
2189 	for (i=0; i<fslocs->locations_count; i++) {
2190 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
2191 		if (status)
2192 			return status;
2193 	}
2194 	return 0;
2195 }
2196 
2197 static u32 nfs4_file_type(umode_t mode)
2198 {
2199 	switch (mode & S_IFMT) {
2200 	case S_IFIFO:	return NF4FIFO;
2201 	case S_IFCHR:	return NF4CHR;
2202 	case S_IFDIR:	return NF4DIR;
2203 	case S_IFBLK:	return NF4BLK;
2204 	case S_IFLNK:	return NF4LNK;
2205 	case S_IFREG:	return NF4REG;
2206 	case S_IFSOCK:	return NF4SOCK;
2207 	default:	return NF4BAD;
2208 	};
2209 }
2210 
2211 static inline __be32
2212 nfsd4_encode_aclname(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2213 		     struct nfs4_ace *ace)
2214 {
2215 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
2216 		return nfs4_acl_write_who(xdr, ace->whotype);
2217 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
2218 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
2219 	else
2220 		return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
2221 }
2222 
2223 static inline __be32
2224 nfsd4_encode_layout_types(struct xdr_stream *xdr, u32 layout_types)
2225 {
2226 	__be32		*p;
2227 	unsigned long	i = hweight_long(layout_types);
2228 
2229 	p = xdr_reserve_space(xdr, 4 + 4 * i);
2230 	if (!p)
2231 		return nfserr_resource;
2232 
2233 	*p++ = cpu_to_be32(i);
2234 
2235 	for (i = LAYOUT_NFSV4_1_FILES; i < LAYOUT_TYPE_MAX; ++i)
2236 		if (layout_types & (1 << i))
2237 			*p++ = cpu_to_be32(i);
2238 
2239 	return 0;
2240 }
2241 
2242 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
2243 			      FATTR4_WORD0_RDATTR_ERROR)
2244 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2245 #define WORD2_ABSENT_FS_ATTRS 0
2246 
2247 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2248 static inline __be32
2249 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2250 			    void *context, int len)
2251 {
2252 	__be32 *p;
2253 
2254 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2255 	if (!p)
2256 		return nfserr_resource;
2257 
2258 	/*
2259 	 * For now we use a 0 here to indicate the null translation; in
2260 	 * the future we may place a call to translation code here.
2261 	 */
2262 	*p++ = cpu_to_be32(0); /* lfs */
2263 	*p++ = cpu_to_be32(0); /* pi */
2264 	p = xdr_encode_opaque(p, context, len);
2265 	return 0;
2266 }
2267 #else
2268 static inline __be32
2269 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2270 			    void *context, int len)
2271 { return 0; }
2272 #endif
2273 
2274 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *bmval2, u32 *rdattr_err)
2275 {
2276 	/* As per referral draft:  */
2277 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2278 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2279 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2280 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2281 			*rdattr_err = NFSERR_MOVED;
2282 		else
2283 			return nfserr_moved;
2284 	}
2285 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2286 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2287 	*bmval2 &= WORD2_ABSENT_FS_ATTRS;
2288 	return 0;
2289 }
2290 
2291 
2292 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2293 {
2294 	struct path path = exp->ex_path;
2295 	int err;
2296 
2297 	path_get(&path);
2298 	while (follow_up(&path)) {
2299 		if (path.dentry != path.mnt->mnt_root)
2300 			break;
2301 	}
2302 	err = vfs_getattr(&path, stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
2303 	path_put(&path);
2304 	return err;
2305 }
2306 
2307 static __be32
2308 nfsd4_encode_bitmap(struct xdr_stream *xdr, u32 bmval0, u32 bmval1, u32 bmval2)
2309 {
2310 	__be32 *p;
2311 
2312 	if (bmval2) {
2313 		p = xdr_reserve_space(xdr, 16);
2314 		if (!p)
2315 			goto out_resource;
2316 		*p++ = cpu_to_be32(3);
2317 		*p++ = cpu_to_be32(bmval0);
2318 		*p++ = cpu_to_be32(bmval1);
2319 		*p++ = cpu_to_be32(bmval2);
2320 	} else if (bmval1) {
2321 		p = xdr_reserve_space(xdr, 12);
2322 		if (!p)
2323 			goto out_resource;
2324 		*p++ = cpu_to_be32(2);
2325 		*p++ = cpu_to_be32(bmval0);
2326 		*p++ = cpu_to_be32(bmval1);
2327 	} else {
2328 		p = xdr_reserve_space(xdr, 8);
2329 		if (!p)
2330 			goto out_resource;
2331 		*p++ = cpu_to_be32(1);
2332 		*p++ = cpu_to_be32(bmval0);
2333 	}
2334 
2335 	return 0;
2336 out_resource:
2337 	return nfserr_resource;
2338 }
2339 
2340 /*
2341  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2342  * ourselves.
2343  */
2344 static __be32
2345 nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
2346 		struct svc_export *exp,
2347 		struct dentry *dentry, u32 *bmval,
2348 		struct svc_rqst *rqstp, int ignore_crossmnt)
2349 {
2350 	u32 bmval0 = bmval[0];
2351 	u32 bmval1 = bmval[1];
2352 	u32 bmval2 = bmval[2];
2353 	struct kstat stat;
2354 	struct svc_fh *tempfh = NULL;
2355 	struct kstatfs statfs;
2356 	__be32 *p;
2357 	int starting_len = xdr->buf->len;
2358 	int attrlen_offset;
2359 	__be32 attrlen;
2360 	u32 dummy;
2361 	u64 dummy64;
2362 	u32 rdattr_err = 0;
2363 	__be32 status;
2364 	int err;
2365 	struct nfs4_acl *acl = NULL;
2366 	void *context = NULL;
2367 	int contextlen;
2368 	bool contextsupport = false;
2369 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2370 	u32 minorversion = resp->cstate.minorversion;
2371 	struct path path = {
2372 		.mnt	= exp->ex_path.mnt,
2373 		.dentry	= dentry,
2374 	};
2375 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2376 
2377 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2378 	BUG_ON(!nfsd_attrs_supported(minorversion, bmval));
2379 
2380 	if (exp->ex_fslocs.migrated) {
2381 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &bmval2, &rdattr_err);
2382 		if (status)
2383 			goto out;
2384 	}
2385 
2386 	err = vfs_getattr(&path, &stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
2387 	if (err)
2388 		goto out_nfserr;
2389 	if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
2390 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
2391 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2392 		       FATTR4_WORD1_SPACE_TOTAL))) {
2393 		err = vfs_statfs(&path, &statfs);
2394 		if (err)
2395 			goto out_nfserr;
2396 	}
2397 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2398 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2399 		status = nfserr_jukebox;
2400 		if (!tempfh)
2401 			goto out;
2402 		fh_init(tempfh, NFS4_FHSIZE);
2403 		status = fh_compose(tempfh, exp, dentry, NULL);
2404 		if (status)
2405 			goto out;
2406 		fhp = tempfh;
2407 	}
2408 	if (bmval0 & FATTR4_WORD0_ACL) {
2409 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2410 		if (err == -EOPNOTSUPP)
2411 			bmval0 &= ~FATTR4_WORD0_ACL;
2412 		else if (err == -EINVAL) {
2413 			status = nfserr_attrnotsupp;
2414 			goto out;
2415 		} else if (err != 0)
2416 			goto out_nfserr;
2417 	}
2418 
2419 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2420 	if ((bmval2 & FATTR4_WORD2_SECURITY_LABEL) ||
2421 	     bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2422 		if (exp->ex_flags & NFSEXP_SECURITY_LABEL)
2423 			err = security_inode_getsecctx(d_inode(dentry),
2424 						&context, &contextlen);
2425 		else
2426 			err = -EOPNOTSUPP;
2427 		contextsupport = (err == 0);
2428 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2429 			if (err == -EOPNOTSUPP)
2430 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2431 			else if (err)
2432 				goto out_nfserr;
2433 		}
2434 	}
2435 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2436 
2437 	status = nfsd4_encode_bitmap(xdr, bmval0, bmval1, bmval2);
2438 	if (status)
2439 		goto out;
2440 
2441 	attrlen_offset = xdr->buf->len;
2442 	p = xdr_reserve_space(xdr, 4);
2443 	if (!p)
2444 		goto out_resource;
2445 	p++;                /* to be backfilled later */
2446 
2447 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2448 		u32 supp[3];
2449 
2450 		memcpy(supp, nfsd_suppattrs[minorversion], sizeof(supp));
2451 
2452 		if (!IS_POSIXACL(dentry->d_inode))
2453 			supp[0] &= ~FATTR4_WORD0_ACL;
2454 		if (!contextsupport)
2455 			supp[2] &= ~FATTR4_WORD2_SECURITY_LABEL;
2456 		if (!supp[2]) {
2457 			p = xdr_reserve_space(xdr, 12);
2458 			if (!p)
2459 				goto out_resource;
2460 			*p++ = cpu_to_be32(2);
2461 			*p++ = cpu_to_be32(supp[0]);
2462 			*p++ = cpu_to_be32(supp[1]);
2463 		} else {
2464 			p = xdr_reserve_space(xdr, 16);
2465 			if (!p)
2466 				goto out_resource;
2467 			*p++ = cpu_to_be32(3);
2468 			*p++ = cpu_to_be32(supp[0]);
2469 			*p++ = cpu_to_be32(supp[1]);
2470 			*p++ = cpu_to_be32(supp[2]);
2471 		}
2472 	}
2473 	if (bmval0 & FATTR4_WORD0_TYPE) {
2474 		p = xdr_reserve_space(xdr, 4);
2475 		if (!p)
2476 			goto out_resource;
2477 		dummy = nfs4_file_type(stat.mode);
2478 		if (dummy == NF4BAD) {
2479 			status = nfserr_serverfault;
2480 			goto out;
2481 		}
2482 		*p++ = cpu_to_be32(dummy);
2483 	}
2484 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2485 		p = xdr_reserve_space(xdr, 4);
2486 		if (!p)
2487 			goto out_resource;
2488 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2489 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT);
2490 		else
2491 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT|
2492 						NFS4_FH_VOL_RENAME);
2493 	}
2494 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2495 		p = xdr_reserve_space(xdr, 8);
2496 		if (!p)
2497 			goto out_resource;
2498 		p = encode_change(p, &stat, d_inode(dentry), exp);
2499 	}
2500 	if (bmval0 & FATTR4_WORD0_SIZE) {
2501 		p = xdr_reserve_space(xdr, 8);
2502 		if (!p)
2503 			goto out_resource;
2504 		p = xdr_encode_hyper(p, stat.size);
2505 	}
2506 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2507 		p = xdr_reserve_space(xdr, 4);
2508 		if (!p)
2509 			goto out_resource;
2510 		*p++ = cpu_to_be32(1);
2511 	}
2512 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2513 		p = xdr_reserve_space(xdr, 4);
2514 		if (!p)
2515 			goto out_resource;
2516 		*p++ = cpu_to_be32(1);
2517 	}
2518 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2519 		p = xdr_reserve_space(xdr, 4);
2520 		if (!p)
2521 			goto out_resource;
2522 		*p++ = cpu_to_be32(0);
2523 	}
2524 	if (bmval0 & FATTR4_WORD0_FSID) {
2525 		p = xdr_reserve_space(xdr, 16);
2526 		if (!p)
2527 			goto out_resource;
2528 		if (exp->ex_fslocs.migrated) {
2529 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
2530 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
2531 		} else switch(fsid_source(fhp)) {
2532 		case FSIDSOURCE_FSID:
2533 			p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
2534 			p = xdr_encode_hyper(p, (u64)0);
2535 			break;
2536 		case FSIDSOURCE_DEV:
2537 			*p++ = cpu_to_be32(0);
2538 			*p++ = cpu_to_be32(MAJOR(stat.dev));
2539 			*p++ = cpu_to_be32(0);
2540 			*p++ = cpu_to_be32(MINOR(stat.dev));
2541 			break;
2542 		case FSIDSOURCE_UUID:
2543 			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
2544 								EX_UUID_LEN);
2545 			break;
2546 		}
2547 	}
2548 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2549 		p = xdr_reserve_space(xdr, 4);
2550 		if (!p)
2551 			goto out_resource;
2552 		*p++ = cpu_to_be32(0);
2553 	}
2554 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2555 		p = xdr_reserve_space(xdr, 4);
2556 		if (!p)
2557 			goto out_resource;
2558 		*p++ = cpu_to_be32(nn->nfsd4_lease);
2559 	}
2560 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2561 		p = xdr_reserve_space(xdr, 4);
2562 		if (!p)
2563 			goto out_resource;
2564 		*p++ = cpu_to_be32(rdattr_err);
2565 	}
2566 	if (bmval0 & FATTR4_WORD0_ACL) {
2567 		struct nfs4_ace *ace;
2568 
2569 		if (acl == NULL) {
2570 			p = xdr_reserve_space(xdr, 4);
2571 			if (!p)
2572 				goto out_resource;
2573 
2574 			*p++ = cpu_to_be32(0);
2575 			goto out_acl;
2576 		}
2577 		p = xdr_reserve_space(xdr, 4);
2578 		if (!p)
2579 			goto out_resource;
2580 		*p++ = cpu_to_be32(acl->naces);
2581 
2582 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2583 			p = xdr_reserve_space(xdr, 4*3);
2584 			if (!p)
2585 				goto out_resource;
2586 			*p++ = cpu_to_be32(ace->type);
2587 			*p++ = cpu_to_be32(ace->flag);
2588 			*p++ = cpu_to_be32(ace->access_mask &
2589 							NFS4_ACE_MASK_ALL);
2590 			status = nfsd4_encode_aclname(xdr, rqstp, ace);
2591 			if (status)
2592 				goto out;
2593 		}
2594 	}
2595 out_acl:
2596 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2597 		p = xdr_reserve_space(xdr, 4);
2598 		if (!p)
2599 			goto out_resource;
2600 		*p++ = cpu_to_be32(IS_POSIXACL(dentry->d_inode) ?
2601 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2602 	}
2603 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2604 		p = xdr_reserve_space(xdr, 4);
2605 		if (!p)
2606 			goto out_resource;
2607 		*p++ = cpu_to_be32(1);
2608 	}
2609 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2610 		p = xdr_reserve_space(xdr, 4);
2611 		if (!p)
2612 			goto out_resource;
2613 		*p++ = cpu_to_be32(0);
2614 	}
2615 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2616 		p = xdr_reserve_space(xdr, 4);
2617 		if (!p)
2618 			goto out_resource;
2619 		*p++ = cpu_to_be32(1);
2620 	}
2621 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2622 		p = xdr_reserve_space(xdr, 4);
2623 		if (!p)
2624 			goto out_resource;
2625 		*p++ = cpu_to_be32(1);
2626 	}
2627 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2628 		p = xdr_reserve_space(xdr, fhp->fh_handle.fh_size + 4);
2629 		if (!p)
2630 			goto out_resource;
2631 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base,
2632 					fhp->fh_handle.fh_size);
2633 	}
2634 	if (bmval0 & FATTR4_WORD0_FILEID) {
2635 		p = xdr_reserve_space(xdr, 8);
2636 		if (!p)
2637 			goto out_resource;
2638 		p = xdr_encode_hyper(p, stat.ino);
2639 	}
2640 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2641 		p = xdr_reserve_space(xdr, 8);
2642 		if (!p)
2643 			goto out_resource;
2644 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2645 	}
2646 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2647 		p = xdr_reserve_space(xdr, 8);
2648 		if (!p)
2649 			goto out_resource;
2650 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2651 	}
2652 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2653 		p = xdr_reserve_space(xdr, 8);
2654 		if (!p)
2655 			goto out_resource;
2656 		p = xdr_encode_hyper(p, (u64) statfs.f_files);
2657 	}
2658 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2659 		status = nfsd4_encode_fs_locations(xdr, rqstp, exp);
2660 		if (status)
2661 			goto out;
2662 	}
2663 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
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_MAXFILESIZE) {
2670 		p = xdr_reserve_space(xdr, 8);
2671 		if (!p)
2672 			goto out_resource;
2673 		p = xdr_encode_hyper(p, exp->ex_path.mnt->mnt_sb->s_maxbytes);
2674 	}
2675 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2676 		p = xdr_reserve_space(xdr, 4);
2677 		if (!p)
2678 			goto out_resource;
2679 		*p++ = cpu_to_be32(255);
2680 	}
2681 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2682 		p = xdr_reserve_space(xdr, 4);
2683 		if (!p)
2684 			goto out_resource;
2685 		*p++ = cpu_to_be32(statfs.f_namelen);
2686 	}
2687 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2688 		p = xdr_reserve_space(xdr, 8);
2689 		if (!p)
2690 			goto out_resource;
2691 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2692 	}
2693 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2694 		p = xdr_reserve_space(xdr, 8);
2695 		if (!p)
2696 			goto out_resource;
2697 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2698 	}
2699 	if (bmval1 & FATTR4_WORD1_MODE) {
2700 		p = xdr_reserve_space(xdr, 4);
2701 		if (!p)
2702 			goto out_resource;
2703 		*p++ = cpu_to_be32(stat.mode & S_IALLUGO);
2704 	}
2705 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2706 		p = xdr_reserve_space(xdr, 4);
2707 		if (!p)
2708 			goto out_resource;
2709 		*p++ = cpu_to_be32(1);
2710 	}
2711 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2712 		p = xdr_reserve_space(xdr, 4);
2713 		if (!p)
2714 			goto out_resource;
2715 		*p++ = cpu_to_be32(stat.nlink);
2716 	}
2717 	if (bmval1 & FATTR4_WORD1_OWNER) {
2718 		status = nfsd4_encode_user(xdr, rqstp, stat.uid);
2719 		if (status)
2720 			goto out;
2721 	}
2722 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2723 		status = nfsd4_encode_group(xdr, rqstp, stat.gid);
2724 		if (status)
2725 			goto out;
2726 	}
2727 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2728 		p = xdr_reserve_space(xdr, 8);
2729 		if (!p)
2730 			goto out_resource;
2731 		*p++ = cpu_to_be32((u32) MAJOR(stat.rdev));
2732 		*p++ = cpu_to_be32((u32) MINOR(stat.rdev));
2733 	}
2734 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2735 		p = xdr_reserve_space(xdr, 8);
2736 		if (!p)
2737 			goto out_resource;
2738 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2739 		p = xdr_encode_hyper(p, dummy64);
2740 	}
2741 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2742 		p = xdr_reserve_space(xdr, 8);
2743 		if (!p)
2744 			goto out_resource;
2745 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2746 		p = xdr_encode_hyper(p, dummy64);
2747 	}
2748 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2749 		p = xdr_reserve_space(xdr, 8);
2750 		if (!p)
2751 			goto out_resource;
2752 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2753 		p = xdr_encode_hyper(p, dummy64);
2754 	}
2755 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2756 		p = xdr_reserve_space(xdr, 8);
2757 		if (!p)
2758 			goto out_resource;
2759 		dummy64 = (u64)stat.blocks << 9;
2760 		p = xdr_encode_hyper(p, dummy64);
2761 	}
2762 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2763 		p = xdr_reserve_space(xdr, 12);
2764 		if (!p)
2765 			goto out_resource;
2766 		p = xdr_encode_hyper(p, (s64)stat.atime.tv_sec);
2767 		*p++ = cpu_to_be32(stat.atime.tv_nsec);
2768 	}
2769 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2770 		p = xdr_reserve_space(xdr, 12);
2771 		if (!p)
2772 			goto out_resource;
2773 		*p++ = cpu_to_be32(0);
2774 		*p++ = cpu_to_be32(1);
2775 		*p++ = cpu_to_be32(0);
2776 	}
2777 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2778 		p = xdr_reserve_space(xdr, 12);
2779 		if (!p)
2780 			goto out_resource;
2781 		p = xdr_encode_hyper(p, (s64)stat.ctime.tv_sec);
2782 		*p++ = cpu_to_be32(stat.ctime.tv_nsec);
2783 	}
2784 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2785 		p = xdr_reserve_space(xdr, 12);
2786 		if (!p)
2787 			goto out_resource;
2788 		p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
2789 		*p++ = cpu_to_be32(stat.mtime.tv_nsec);
2790 	}
2791 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2792 		struct kstat parent_stat;
2793 		u64 ino = stat.ino;
2794 
2795 		p = xdr_reserve_space(xdr, 8);
2796 		if (!p)
2797                 	goto out_resource;
2798 		/*
2799 		 * Get parent's attributes if not ignoring crossmount
2800 		 * and this is the root of a cross-mounted filesystem.
2801 		 */
2802 		if (ignore_crossmnt == 0 &&
2803 		    dentry == exp->ex_path.mnt->mnt_root) {
2804 			err = get_parent_attributes(exp, &parent_stat);
2805 			if (err)
2806 				goto out_nfserr;
2807 			ino = parent_stat.ino;
2808 		}
2809 		p = xdr_encode_hyper(p, ino);
2810 	}
2811 #ifdef CONFIG_NFSD_PNFS
2812 	if (bmval1 & FATTR4_WORD1_FS_LAYOUT_TYPES) {
2813 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
2814 		if (status)
2815 			goto out;
2816 	}
2817 
2818 	if (bmval2 & FATTR4_WORD2_LAYOUT_TYPES) {
2819 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
2820 		if (status)
2821 			goto out;
2822 	}
2823 
2824 	if (bmval2 & FATTR4_WORD2_LAYOUT_BLKSIZE) {
2825 		p = xdr_reserve_space(xdr, 4);
2826 		if (!p)
2827 			goto out_resource;
2828 		*p++ = cpu_to_be32(stat.blksize);
2829 	}
2830 #endif /* CONFIG_NFSD_PNFS */
2831 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2832 		u32 supp[3];
2833 
2834 		memcpy(supp, nfsd_suppattrs[minorversion], sizeof(supp));
2835 		supp[0] &= NFSD_SUPPATTR_EXCLCREAT_WORD0;
2836 		supp[1] &= NFSD_SUPPATTR_EXCLCREAT_WORD1;
2837 		supp[2] &= NFSD_SUPPATTR_EXCLCREAT_WORD2;
2838 
2839 		status = nfsd4_encode_bitmap(xdr, supp[0], supp[1], supp[2]);
2840 		if (status)
2841 			goto out;
2842 	}
2843 
2844 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2845 		status = nfsd4_encode_security_label(xdr, rqstp, context,
2846 								contextlen);
2847 		if (status)
2848 			goto out;
2849 	}
2850 
2851 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
2852 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
2853 	status = nfs_ok;
2854 
2855 out:
2856 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2857 	if (context)
2858 		security_release_secctx(context, contextlen);
2859 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2860 	kfree(acl);
2861 	if (tempfh) {
2862 		fh_put(tempfh);
2863 		kfree(tempfh);
2864 	}
2865 	if (status)
2866 		xdr_truncate_encode(xdr, starting_len);
2867 	return status;
2868 out_nfserr:
2869 	status = nfserrno(err);
2870 	goto out;
2871 out_resource:
2872 	status = nfserr_resource;
2873 	goto out;
2874 }
2875 
2876 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
2877 				struct xdr_buf *buf, __be32 *p, int bytes)
2878 {
2879 	xdr->scratch.iov_len = 0;
2880 	memset(buf, 0, sizeof(struct xdr_buf));
2881 	buf->head[0].iov_base = p;
2882 	buf->head[0].iov_len = 0;
2883 	buf->len = 0;
2884 	xdr->buf = buf;
2885 	xdr->iov = buf->head;
2886 	xdr->p = p;
2887 	xdr->end = (void *)p + bytes;
2888 	buf->buflen = bytes;
2889 }
2890 
2891 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
2892 			struct svc_fh *fhp, struct svc_export *exp,
2893 			struct dentry *dentry, u32 *bmval,
2894 			struct svc_rqst *rqstp, int ignore_crossmnt)
2895 {
2896 	struct xdr_buf dummy;
2897 	struct xdr_stream xdr;
2898 	__be32 ret;
2899 
2900 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
2901 	ret = nfsd4_encode_fattr(&xdr, fhp, exp, dentry, bmval, rqstp,
2902 							ignore_crossmnt);
2903 	*p = xdr.p;
2904 	return ret;
2905 }
2906 
2907 static inline int attributes_need_mount(u32 *bmval)
2908 {
2909 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2910 		return 1;
2911 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2912 		return 1;
2913 	return 0;
2914 }
2915 
2916 static __be32
2917 nfsd4_encode_dirent_fattr(struct xdr_stream *xdr, struct nfsd4_readdir *cd,
2918 			const char *name, int namlen)
2919 {
2920 	struct svc_export *exp = cd->rd_fhp->fh_export;
2921 	struct dentry *dentry;
2922 	__be32 nfserr;
2923 	int ignore_crossmnt = 0;
2924 
2925 	dentry = lookup_one_len_unlocked(name, cd->rd_fhp->fh_dentry, namlen);
2926 	if (IS_ERR(dentry))
2927 		return nfserrno(PTR_ERR(dentry));
2928 	if (d_really_is_negative(dentry)) {
2929 		/*
2930 		 * we're not holding the i_mutex here, so there's
2931 		 * a window where this directory entry could have gone
2932 		 * away.
2933 		 */
2934 		dput(dentry);
2935 		return nfserr_noent;
2936 	}
2937 
2938 	exp_get(exp);
2939 	/*
2940 	 * In the case of a mountpoint, the client may be asking for
2941 	 * attributes that are only properties of the underlying filesystem
2942 	 * as opposed to the cross-mounted file system. In such a case,
2943 	 * we will not follow the cross mount and will fill the attribtutes
2944 	 * directly from the mountpoint dentry.
2945 	 */
2946 	if (nfsd_mountpoint(dentry, exp)) {
2947 		int err;
2948 
2949 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
2950 				&& !attributes_need_mount(cd->rd_bmval)) {
2951 			ignore_crossmnt = 1;
2952 			goto out_encode;
2953 		}
2954 		/*
2955 		 * Why the heck aren't we just using nfsd_lookup??
2956 		 * Different "."/".." handling?  Something else?
2957 		 * At least, add a comment here to explain....
2958 		 */
2959 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
2960 		if (err) {
2961 			nfserr = nfserrno(err);
2962 			goto out_put;
2963 		}
2964 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
2965 		if (nfserr)
2966 			goto out_put;
2967 
2968 	}
2969 out_encode:
2970 	nfserr = nfsd4_encode_fattr(xdr, NULL, exp, dentry, cd->rd_bmval,
2971 					cd->rd_rqstp, ignore_crossmnt);
2972 out_put:
2973 	dput(dentry);
2974 	exp_put(exp);
2975 	return nfserr;
2976 }
2977 
2978 static __be32 *
2979 nfsd4_encode_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
2980 {
2981 	__be32 *p;
2982 
2983 	p = xdr_reserve_space(xdr, 20);
2984 	if (!p)
2985 		return NULL;
2986 	*p++ = htonl(2);
2987 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
2988 	*p++ = htonl(0);			 /* bmval1 */
2989 
2990 	*p++ = htonl(4);     /* attribute length */
2991 	*p++ = nfserr;       /* no htonl */
2992 	return p;
2993 }
2994 
2995 static int
2996 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
2997 		    loff_t offset, u64 ino, unsigned int d_type)
2998 {
2999 	struct readdir_cd *ccd = ccdv;
3000 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
3001 	struct xdr_stream *xdr = cd->xdr;
3002 	int start_offset = xdr->buf->len;
3003 	int cookie_offset;
3004 	u32 name_and_cookie;
3005 	int entry_bytes;
3006 	__be32 nfserr = nfserr_toosmall;
3007 	__be64 wire_offset;
3008 	__be32 *p;
3009 
3010 	/* In nfsv4, "." and ".." never make it onto the wire.. */
3011 	if (name && isdotent(name, namlen)) {
3012 		cd->common.err = nfs_ok;
3013 		return 0;
3014 	}
3015 
3016 	if (cd->cookie_offset) {
3017 		wire_offset = cpu_to_be64(offset);
3018 		write_bytes_to_xdr_buf(xdr->buf, cd->cookie_offset,
3019 							&wire_offset, 8);
3020 	}
3021 
3022 	p = xdr_reserve_space(xdr, 4);
3023 	if (!p)
3024 		goto fail;
3025 	*p++ = xdr_one;                             /* mark entry present */
3026 	cookie_offset = xdr->buf->len;
3027 	p = xdr_reserve_space(xdr, 3*4 + namlen);
3028 	if (!p)
3029 		goto fail;
3030 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
3031 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
3032 
3033 	nfserr = nfsd4_encode_dirent_fattr(xdr, cd, name, namlen);
3034 	switch (nfserr) {
3035 	case nfs_ok:
3036 		break;
3037 	case nfserr_resource:
3038 		nfserr = nfserr_toosmall;
3039 		goto fail;
3040 	case nfserr_noent:
3041 		xdr_truncate_encode(xdr, start_offset);
3042 		goto skip_entry;
3043 	default:
3044 		/*
3045 		 * If the client requested the RDATTR_ERROR attribute,
3046 		 * we stuff the error code into this attribute
3047 		 * and continue.  If this attribute was not requested,
3048 		 * then in accordance with the spec, we fail the
3049 		 * entire READDIR operation(!)
3050 		 */
3051 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
3052 			goto fail;
3053 		p = nfsd4_encode_rdattr_error(xdr, nfserr);
3054 		if (p == NULL) {
3055 			nfserr = nfserr_toosmall;
3056 			goto fail;
3057 		}
3058 	}
3059 	nfserr = nfserr_toosmall;
3060 	entry_bytes = xdr->buf->len - start_offset;
3061 	if (entry_bytes > cd->rd_maxcount)
3062 		goto fail;
3063 	cd->rd_maxcount -= entry_bytes;
3064 	/*
3065 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so
3066 	 * let's always let through the first entry, at least:
3067 	 */
3068 	if (!cd->rd_dircount)
3069 		goto fail;
3070 	name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8;
3071 	if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
3072 		goto fail;
3073 	cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
3074 
3075 	cd->cookie_offset = cookie_offset;
3076 skip_entry:
3077 	cd->common.err = nfs_ok;
3078 	return 0;
3079 fail:
3080 	xdr_truncate_encode(xdr, start_offset);
3081 	cd->common.err = nfserr;
3082 	return -EINVAL;
3083 }
3084 
3085 static __be32
3086 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
3087 {
3088 	__be32 *p;
3089 
3090 	p = xdr_reserve_space(xdr, sizeof(stateid_t));
3091 	if (!p)
3092 		return nfserr_resource;
3093 	*p++ = cpu_to_be32(sid->si_generation);
3094 	p = xdr_encode_opaque_fixed(p, &sid->si_opaque,
3095 					sizeof(stateid_opaque_t));
3096 	return 0;
3097 }
3098 
3099 static __be32
3100 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
3101 {
3102 	struct xdr_stream *xdr = &resp->xdr;
3103 	__be32 *p;
3104 
3105 	if (!nfserr) {
3106 		p = xdr_reserve_space(xdr, 8);
3107 		if (!p)
3108 			return nfserr_resource;
3109 		*p++ = cpu_to_be32(access->ac_supported);
3110 		*p++ = cpu_to_be32(access->ac_resp_access);
3111 	}
3112 	return nfserr;
3113 }
3114 
3115 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
3116 {
3117 	struct xdr_stream *xdr = &resp->xdr;
3118 	__be32 *p;
3119 
3120 	if (!nfserr) {
3121 		p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 8);
3122 		if (!p)
3123 			return nfserr_resource;
3124 		p = xdr_encode_opaque_fixed(p, bcts->sessionid.data,
3125 						NFS4_MAX_SESSIONID_LEN);
3126 		*p++ = cpu_to_be32(bcts->dir);
3127 		/* Upshifting from TCP to RDMA is not supported */
3128 		*p++ = cpu_to_be32(0);
3129 	}
3130 	return nfserr;
3131 }
3132 
3133 static __be32
3134 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
3135 {
3136 	struct xdr_stream *xdr = &resp->xdr;
3137 
3138 	if (!nfserr)
3139 		nfserr = nfsd4_encode_stateid(xdr, &close->cl_stateid);
3140 
3141 	return nfserr;
3142 }
3143 
3144 
3145 static __be32
3146 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
3147 {
3148 	struct xdr_stream *xdr = &resp->xdr;
3149 	__be32 *p;
3150 
3151 	if (!nfserr) {
3152 		p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3153 		if (!p)
3154 			return nfserr_resource;
3155 		p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
3156 						NFS4_VERIFIER_SIZE);
3157 	}
3158 	return nfserr;
3159 }
3160 
3161 static __be32
3162 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
3163 {
3164 	struct xdr_stream *xdr = &resp->xdr;
3165 	__be32 *p;
3166 
3167 	if (!nfserr) {
3168 		p = xdr_reserve_space(xdr, 20);
3169 		if (!p)
3170 			return nfserr_resource;
3171 		encode_cinfo(p, &create->cr_cinfo);
3172 		nfserr = nfsd4_encode_bitmap(xdr, create->cr_bmval[0],
3173 				create->cr_bmval[1], create->cr_bmval[2]);
3174 	}
3175 	return nfserr;
3176 }
3177 
3178 static __be32
3179 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
3180 {
3181 	struct svc_fh *fhp = getattr->ga_fhp;
3182 	struct xdr_stream *xdr = &resp->xdr;
3183 
3184 	if (nfserr)
3185 		return nfserr;
3186 
3187 	nfserr = nfsd4_encode_fattr(xdr, fhp, fhp->fh_export, fhp->fh_dentry,
3188 				    getattr->ga_bmval,
3189 				    resp->rqstp, 0);
3190 	return nfserr;
3191 }
3192 
3193 static __be32
3194 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
3195 {
3196 	struct xdr_stream *xdr = &resp->xdr;
3197 	struct svc_fh *fhp = *fhpp;
3198 	unsigned int len;
3199 	__be32 *p;
3200 
3201 	if (!nfserr) {
3202 		len = fhp->fh_handle.fh_size;
3203 		p = xdr_reserve_space(xdr, len + 4);
3204 		if (!p)
3205 			return nfserr_resource;
3206 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base, len);
3207 	}
3208 	return nfserr;
3209 }
3210 
3211 /*
3212 * Including all fields other than the name, a LOCK4denied structure requires
3213 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
3214 */
3215 static __be32
3216 nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld)
3217 {
3218 	struct xdr_netobj *conf = &ld->ld_owner;
3219 	__be32 *p;
3220 
3221 again:
3222 	p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len));
3223 	if (!p) {
3224 		/*
3225 		 * Don't fail to return the result just because we can't
3226 		 * return the conflicting open:
3227 		 */
3228 		if (conf->len) {
3229 			kfree(conf->data);
3230 			conf->len = 0;
3231 			conf->data = NULL;
3232 			goto again;
3233 		}
3234 		return nfserr_resource;
3235 	}
3236 	p = xdr_encode_hyper(p, ld->ld_start);
3237 	p = xdr_encode_hyper(p, ld->ld_length);
3238 	*p++ = cpu_to_be32(ld->ld_type);
3239 	if (conf->len) {
3240 		p = xdr_encode_opaque_fixed(p, &ld->ld_clientid, 8);
3241 		p = xdr_encode_opaque(p, conf->data, conf->len);
3242 		kfree(conf->data);
3243 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
3244 		p = xdr_encode_hyper(p, (u64)0); /* clientid */
3245 		*p++ = cpu_to_be32(0); /* length of owner name */
3246 	}
3247 	return nfserr_denied;
3248 }
3249 
3250 static __be32
3251 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
3252 {
3253 	struct xdr_stream *xdr = &resp->xdr;
3254 
3255 	if (!nfserr)
3256 		nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid);
3257 	else if (nfserr == nfserr_denied)
3258 		nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied);
3259 
3260 	return nfserr;
3261 }
3262 
3263 static __be32
3264 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
3265 {
3266 	struct xdr_stream *xdr = &resp->xdr;
3267 
3268 	if (nfserr == nfserr_denied)
3269 		nfsd4_encode_lock_denied(xdr, &lockt->lt_denied);
3270 	return nfserr;
3271 }
3272 
3273 static __be32
3274 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
3275 {
3276 	struct xdr_stream *xdr = &resp->xdr;
3277 
3278 	if (!nfserr)
3279 		nfserr = nfsd4_encode_stateid(xdr, &locku->lu_stateid);
3280 
3281 	return nfserr;
3282 }
3283 
3284 
3285 static __be32
3286 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
3287 {
3288 	struct xdr_stream *xdr = &resp->xdr;
3289 	__be32 *p;
3290 
3291 	if (!nfserr) {
3292 		p = xdr_reserve_space(xdr, 20);
3293 		if (!p)
3294 			return nfserr_resource;
3295 		p = encode_cinfo(p, &link->li_cinfo);
3296 	}
3297 	return nfserr;
3298 }
3299 
3300 
3301 static __be32
3302 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
3303 {
3304 	struct xdr_stream *xdr = &resp->xdr;
3305 	__be32 *p;
3306 
3307 	if (nfserr)
3308 		goto out;
3309 
3310 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
3311 	if (nfserr)
3312 		goto out;
3313 	p = xdr_reserve_space(xdr, 24);
3314 	if (!p)
3315 		return nfserr_resource;
3316 	p = encode_cinfo(p, &open->op_cinfo);
3317 	*p++ = cpu_to_be32(open->op_rflags);
3318 
3319 	nfserr = nfsd4_encode_bitmap(xdr, open->op_bmval[0], open->op_bmval[1],
3320 					open->op_bmval[2]);
3321 	if (nfserr)
3322 		goto out;
3323 
3324 	p = xdr_reserve_space(xdr, 4);
3325 	if (!p)
3326 		return nfserr_resource;
3327 
3328 	*p++ = cpu_to_be32(open->op_delegate_type);
3329 	switch (open->op_delegate_type) {
3330 	case NFS4_OPEN_DELEGATE_NONE:
3331 		break;
3332 	case NFS4_OPEN_DELEGATE_READ:
3333 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3334 		if (nfserr)
3335 			return nfserr;
3336 		p = xdr_reserve_space(xdr, 20);
3337 		if (!p)
3338 			return nfserr_resource;
3339 		*p++ = cpu_to_be32(open->op_recall);
3340 
3341 		/*
3342 		 * TODO: ACE's in delegations
3343 		 */
3344 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3345 		*p++ = cpu_to_be32(0);
3346 		*p++ = cpu_to_be32(0);
3347 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3348 		break;
3349 	case NFS4_OPEN_DELEGATE_WRITE:
3350 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3351 		if (nfserr)
3352 			return nfserr;
3353 		p = xdr_reserve_space(xdr, 32);
3354 		if (!p)
3355 			return nfserr_resource;
3356 		*p++ = cpu_to_be32(0);
3357 
3358 		/*
3359 		 * TODO: space_limit's in delegations
3360 		 */
3361 		*p++ = cpu_to_be32(NFS4_LIMIT_SIZE);
3362 		*p++ = cpu_to_be32(~(u32)0);
3363 		*p++ = cpu_to_be32(~(u32)0);
3364 
3365 		/*
3366 		 * TODO: ACE's in delegations
3367 		 */
3368 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3369 		*p++ = cpu_to_be32(0);
3370 		*p++ = cpu_to_be32(0);
3371 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3372 		break;
3373 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
3374 		switch (open->op_why_no_deleg) {
3375 		case WND4_CONTENTION:
3376 		case WND4_RESOURCE:
3377 			p = xdr_reserve_space(xdr, 8);
3378 			if (!p)
3379 				return nfserr_resource;
3380 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3381 			/* deleg signaling not supported yet: */
3382 			*p++ = cpu_to_be32(0);
3383 			break;
3384 		default:
3385 			p = xdr_reserve_space(xdr, 4);
3386 			if (!p)
3387 				return nfserr_resource;
3388 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3389 		}
3390 		break;
3391 	default:
3392 		BUG();
3393 	}
3394 	/* XXX save filehandle here */
3395 out:
3396 	return nfserr;
3397 }
3398 
3399 static __be32
3400 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
3401 {
3402 	struct xdr_stream *xdr = &resp->xdr;
3403 
3404 	if (!nfserr)
3405 		nfserr = nfsd4_encode_stateid(xdr, &oc->oc_resp_stateid);
3406 
3407 	return nfserr;
3408 }
3409 
3410 static __be32
3411 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
3412 {
3413 	struct xdr_stream *xdr = &resp->xdr;
3414 
3415 	if (!nfserr)
3416 		nfserr = nfsd4_encode_stateid(xdr, &od->od_stateid);
3417 
3418 	return nfserr;
3419 }
3420 
3421 static __be32 nfsd4_encode_splice_read(
3422 				struct nfsd4_compoundres *resp,
3423 				struct nfsd4_read *read,
3424 				struct file *file, unsigned long maxcount)
3425 {
3426 	struct xdr_stream *xdr = &resp->xdr;
3427 	struct xdr_buf *buf = xdr->buf;
3428 	u32 eof;
3429 	long len;
3430 	int space_left;
3431 	__be32 nfserr;
3432 	__be32 *p = xdr->p - 2;
3433 
3434 	/* Make sure there will be room for padding if needed */
3435 	if (xdr->end - xdr->p < 1)
3436 		return nfserr_resource;
3437 
3438 	len = maxcount;
3439 	nfserr = nfsd_splice_read(read->rd_rqstp, file,
3440 				  read->rd_offset, &maxcount);
3441 	if (nfserr) {
3442 		/*
3443 		 * nfsd_splice_actor may have already messed with the
3444 		 * page length; reset it so as not to confuse
3445 		 * xdr_truncate_encode:
3446 		 */
3447 		buf->page_len = 0;
3448 		return nfserr;
3449 	}
3450 
3451 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3452 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3453 
3454 	*(p++) = htonl(eof);
3455 	*(p++) = htonl(maxcount);
3456 
3457 	buf->page_len = maxcount;
3458 	buf->len += maxcount;
3459 	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
3460 							/ PAGE_SIZE;
3461 
3462 	/* Use rest of head for padding and remaining ops: */
3463 	buf->tail[0].iov_base = xdr->p;
3464 	buf->tail[0].iov_len = 0;
3465 	xdr->iov = buf->tail;
3466 	if (maxcount&3) {
3467 		int pad = 4 - (maxcount&3);
3468 
3469 		*(xdr->p++) = 0;
3470 
3471 		buf->tail[0].iov_base += maxcount&3;
3472 		buf->tail[0].iov_len = pad;
3473 		buf->len += pad;
3474 	}
3475 
3476 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
3477 				buf->buflen - buf->len);
3478 	buf->buflen = buf->len + space_left;
3479 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
3480 
3481 	return 0;
3482 }
3483 
3484 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
3485 				 struct nfsd4_read *read,
3486 				 struct file *file, unsigned long maxcount)
3487 {
3488 	struct xdr_stream *xdr = &resp->xdr;
3489 	u32 eof;
3490 	int v;
3491 	int starting_len = xdr->buf->len - 8;
3492 	long len;
3493 	int thislen;
3494 	__be32 nfserr;
3495 	__be32 tmp;
3496 	__be32 *p;
3497 	u32 zzz = 0;
3498 	int pad;
3499 
3500 	len = maxcount;
3501 	v = 0;
3502 
3503 	thislen = min_t(long, len, ((void *)xdr->end - (void *)xdr->p));
3504 	p = xdr_reserve_space(xdr, (thislen+3)&~3);
3505 	WARN_ON_ONCE(!p);
3506 	resp->rqstp->rq_vec[v].iov_base = p;
3507 	resp->rqstp->rq_vec[v].iov_len = thislen;
3508 	v++;
3509 	len -= thislen;
3510 
3511 	while (len) {
3512 		thislen = min_t(long, len, PAGE_SIZE);
3513 		p = xdr_reserve_space(xdr, (thislen+3)&~3);
3514 		WARN_ON_ONCE(!p);
3515 		resp->rqstp->rq_vec[v].iov_base = p;
3516 		resp->rqstp->rq_vec[v].iov_len = thislen;
3517 		v++;
3518 		len -= thislen;
3519 	}
3520 	read->rd_vlen = v;
3521 
3522 	len = maxcount;
3523 	nfserr = nfsd_readv(file, read->rd_offset, resp->rqstp->rq_vec,
3524 			read->rd_vlen, &maxcount);
3525 	if (nfserr)
3526 		return nfserr;
3527 	xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3));
3528 
3529 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3530 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3531 
3532 	tmp = htonl(eof);
3533 	write_bytes_to_xdr_buf(xdr->buf, starting_len    , &tmp, 4);
3534 	tmp = htonl(maxcount);
3535 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
3536 
3537 	pad = (maxcount&3) ? 4 - (maxcount&3) : 0;
3538 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 8 + maxcount,
3539 								&zzz, pad);
3540 	return 0;
3541 
3542 }
3543 
3544 static __be32
3545 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
3546 		  struct nfsd4_read *read)
3547 {
3548 	unsigned long maxcount;
3549 	struct xdr_stream *xdr = &resp->xdr;
3550 	struct file *file = read->rd_filp;
3551 	int starting_len = xdr->buf->len;
3552 	struct raparms *ra = NULL;
3553 	__be32 *p;
3554 
3555 	if (nfserr)
3556 		goto out;
3557 
3558 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
3559 	if (!p) {
3560 		WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
3561 		nfserr = nfserr_resource;
3562 		goto out;
3563 	}
3564 	if (resp->xdr.buf->page_len &&
3565 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
3566 		WARN_ON_ONCE(1);
3567 		nfserr = nfserr_resource;
3568 		goto out;
3569 	}
3570 	xdr_commit_encode(xdr);
3571 
3572 	maxcount = svc_max_payload(resp->rqstp);
3573 	maxcount = min_t(unsigned long, maxcount,
3574 			 (xdr->buf->buflen - xdr->buf->len));
3575 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
3576 
3577 	if (read->rd_tmp_file)
3578 		ra = nfsd_init_raparms(file);
3579 
3580 	if (file->f_op->splice_read &&
3581 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
3582 		nfserr = nfsd4_encode_splice_read(resp, read, file, maxcount);
3583 	else
3584 		nfserr = nfsd4_encode_readv(resp, read, file, maxcount);
3585 
3586 	if (ra)
3587 		nfsd_put_raparams(file, ra);
3588 
3589 	if (nfserr)
3590 		xdr_truncate_encode(xdr, starting_len);
3591 
3592 out:
3593 	if (file)
3594 		fput(file);
3595 	return nfserr;
3596 }
3597 
3598 static __be32
3599 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3600 {
3601 	int maxcount;
3602 	__be32 wire_count;
3603 	int zero = 0;
3604 	struct xdr_stream *xdr = &resp->xdr;
3605 	int length_offset = xdr->buf->len;
3606 	__be32 *p;
3607 
3608 	if (nfserr)
3609 		return nfserr;
3610 
3611 	p = xdr_reserve_space(xdr, 4);
3612 	if (!p)
3613 		return nfserr_resource;
3614 	maxcount = PAGE_SIZE;
3615 
3616 	p = xdr_reserve_space(xdr, maxcount);
3617 	if (!p)
3618 		return nfserr_resource;
3619 	/*
3620 	 * XXX: By default, vfs_readlink() will truncate symlinks if they
3621 	 * would overflow the buffer.  Is this kosher in NFSv4?  If not, one
3622 	 * easy fix is: if vfs_readlink() precisely fills the buffer, assume
3623 	 * that truncation occurred, and return NFS4ERR_RESOURCE.
3624 	 */
3625 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
3626 						(char *)p, &maxcount);
3627 	if (nfserr == nfserr_isdir)
3628 		nfserr = nfserr_inval;
3629 	if (nfserr) {
3630 		xdr_truncate_encode(xdr, length_offset);
3631 		return nfserr;
3632 	}
3633 
3634 	wire_count = htonl(maxcount);
3635 	write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
3636 	xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
3637 	if (maxcount & 3)
3638 		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
3639 						&zero, 4 - (maxcount&3));
3640 	return 0;
3641 }
3642 
3643 static __be32
3644 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3645 {
3646 	int maxcount;
3647 	int bytes_left;
3648 	loff_t offset;
3649 	__be64 wire_offset;
3650 	struct xdr_stream *xdr = &resp->xdr;
3651 	int starting_len = xdr->buf->len;
3652 	__be32 *p;
3653 
3654 	if (nfserr)
3655 		return nfserr;
3656 
3657 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3658 	if (!p)
3659 		return nfserr_resource;
3660 
3661 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3662 	*p++ = cpu_to_be32(0);
3663 	*p++ = cpu_to_be32(0);
3664 	resp->xdr.buf->head[0].iov_len = ((char *)resp->xdr.p)
3665 				- (char *)resp->xdr.buf->head[0].iov_base;
3666 
3667 	/*
3668 	 * Number of bytes left for directory entries allowing for the
3669 	 * final 8 bytes of the readdir and a following failed op:
3670 	 */
3671 	bytes_left = xdr->buf->buflen - xdr->buf->len
3672 			- COMPOUND_ERR_SLACK_SPACE - 8;
3673 	if (bytes_left < 0) {
3674 		nfserr = nfserr_resource;
3675 		goto err_no_verf;
3676 	}
3677 	maxcount = min_t(u32, readdir->rd_maxcount, INT_MAX);
3678 	/*
3679 	 * Note the rfc defines rd_maxcount as the size of the
3680 	 * READDIR4resok structure, which includes the verifier above
3681 	 * and the 8 bytes encoded at the end of this function:
3682 	 */
3683 	if (maxcount < 16) {
3684 		nfserr = nfserr_toosmall;
3685 		goto err_no_verf;
3686 	}
3687 	maxcount = min_t(int, maxcount-16, bytes_left);
3688 
3689 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
3690 	if (!readdir->rd_dircount)
3691 		readdir->rd_dircount = INT_MAX;
3692 
3693 	readdir->xdr = xdr;
3694 	readdir->rd_maxcount = maxcount;
3695 	readdir->common.err = 0;
3696 	readdir->cookie_offset = 0;
3697 
3698 	offset = readdir->rd_cookie;
3699 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3700 			      &offset,
3701 			      &readdir->common, nfsd4_encode_dirent);
3702 	if (nfserr == nfs_ok &&
3703 	    readdir->common.err == nfserr_toosmall &&
3704 	    xdr->buf->len == starting_len + 8) {
3705 		/* nothing encoded; which limit did we hit?: */
3706 		if (maxcount - 16 < bytes_left)
3707 			/* It was the fault of rd_maxcount: */
3708 			nfserr = nfserr_toosmall;
3709 		else
3710 			/* We ran out of buffer space: */
3711 			nfserr = nfserr_resource;
3712 	}
3713 	if (nfserr)
3714 		goto err_no_verf;
3715 
3716 	if (readdir->cookie_offset) {
3717 		wire_offset = cpu_to_be64(offset);
3718 		write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset,
3719 							&wire_offset, 8);
3720 	}
3721 
3722 	p = xdr_reserve_space(xdr, 8);
3723 	if (!p) {
3724 		WARN_ON_ONCE(1);
3725 		goto err_no_verf;
3726 	}
3727 	*p++ = 0;	/* no more entries */
3728 	*p++ = htonl(readdir->common.err == nfserr_eof);
3729 
3730 	return 0;
3731 err_no_verf:
3732 	xdr_truncate_encode(xdr, starting_len);
3733 	return nfserr;
3734 }
3735 
3736 static __be32
3737 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3738 {
3739 	struct xdr_stream *xdr = &resp->xdr;
3740 	__be32 *p;
3741 
3742 	if (!nfserr) {
3743 		p = xdr_reserve_space(xdr, 20);
3744 		if (!p)
3745 			return nfserr_resource;
3746 		p = encode_cinfo(p, &remove->rm_cinfo);
3747 	}
3748 	return nfserr;
3749 }
3750 
3751 static __be32
3752 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3753 {
3754 	struct xdr_stream *xdr = &resp->xdr;
3755 	__be32 *p;
3756 
3757 	if (!nfserr) {
3758 		p = xdr_reserve_space(xdr, 40);
3759 		if (!p)
3760 			return nfserr_resource;
3761 		p = encode_cinfo(p, &rename->rn_sinfo);
3762 		p = encode_cinfo(p, &rename->rn_tinfo);
3763 	}
3764 	return nfserr;
3765 }
3766 
3767 static __be32
3768 nfsd4_do_encode_secinfo(struct xdr_stream *xdr,
3769 			 __be32 nfserr, struct svc_export *exp)
3770 {
3771 	u32 i, nflavs, supported;
3772 	struct exp_flavor_info *flavs;
3773 	struct exp_flavor_info def_flavs[2];
3774 	__be32 *p, *flavorsp;
3775 	static bool report = true;
3776 
3777 	if (nfserr)
3778 		goto out;
3779 	nfserr = nfserr_resource;
3780 	if (exp->ex_nflavors) {
3781 		flavs = exp->ex_flavors;
3782 		nflavs = exp->ex_nflavors;
3783 	} else { /* Handling of some defaults in absence of real secinfo: */
3784 		flavs = def_flavs;
3785 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3786 			nflavs = 2;
3787 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3788 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3789 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3790 			nflavs = 1;
3791 			flavs[0].pseudoflavor
3792 					= svcauth_gss_flavor(exp->ex_client);
3793 		} else {
3794 			nflavs = 1;
3795 			flavs[0].pseudoflavor
3796 					= exp->ex_client->flavour->flavour;
3797 		}
3798 	}
3799 
3800 	supported = 0;
3801 	p = xdr_reserve_space(xdr, 4);
3802 	if (!p)
3803 		goto out;
3804 	flavorsp = p++;		/* to be backfilled later */
3805 
3806 	for (i = 0; i < nflavs; i++) {
3807 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
3808 		struct rpcsec_gss_info info;
3809 
3810 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
3811 			supported++;
3812 			p = xdr_reserve_space(xdr, 4 + 4 +
3813 					      XDR_LEN(info.oid.len) + 4 + 4);
3814 			if (!p)
3815 				goto out;
3816 			*p++ = cpu_to_be32(RPC_AUTH_GSS);
3817 			p = xdr_encode_opaque(p,  info.oid.data, info.oid.len);
3818 			*p++ = cpu_to_be32(info.qop);
3819 			*p++ = cpu_to_be32(info.service);
3820 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
3821 			supported++;
3822 			p = xdr_reserve_space(xdr, 4);
3823 			if (!p)
3824 				goto out;
3825 			*p++ = cpu_to_be32(pf);
3826 		} else {
3827 			if (report)
3828 				pr_warn("NFS: SECINFO: security flavor %u "
3829 					"is not supported\n", pf);
3830 		}
3831 	}
3832 
3833 	if (nflavs != supported)
3834 		report = false;
3835 	*flavorsp = htonl(supported);
3836 	nfserr = 0;
3837 out:
3838 	if (exp)
3839 		exp_put(exp);
3840 	return nfserr;
3841 }
3842 
3843 static __be32
3844 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3845 		     struct nfsd4_secinfo *secinfo)
3846 {
3847 	struct xdr_stream *xdr = &resp->xdr;
3848 
3849 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->si_exp);
3850 }
3851 
3852 static __be32
3853 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3854 		     struct nfsd4_secinfo_no_name *secinfo)
3855 {
3856 	struct xdr_stream *xdr = &resp->xdr;
3857 
3858 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->sin_exp);
3859 }
3860 
3861 /*
3862  * The SETATTR encode routine is special -- it always encodes a bitmap,
3863  * regardless of the error status.
3864  */
3865 static __be32
3866 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3867 {
3868 	struct xdr_stream *xdr = &resp->xdr;
3869 	__be32 *p;
3870 
3871 	p = xdr_reserve_space(xdr, 16);
3872 	if (!p)
3873 		return nfserr_resource;
3874 	if (nfserr) {
3875 		*p++ = cpu_to_be32(3);
3876 		*p++ = cpu_to_be32(0);
3877 		*p++ = cpu_to_be32(0);
3878 		*p++ = cpu_to_be32(0);
3879 	}
3880 	else {
3881 		*p++ = cpu_to_be32(3);
3882 		*p++ = cpu_to_be32(setattr->sa_bmval[0]);
3883 		*p++ = cpu_to_be32(setattr->sa_bmval[1]);
3884 		*p++ = cpu_to_be32(setattr->sa_bmval[2]);
3885 	}
3886 	return nfserr;
3887 }
3888 
3889 static __be32
3890 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3891 {
3892 	struct xdr_stream *xdr = &resp->xdr;
3893 	__be32 *p;
3894 
3895 	if (!nfserr) {
3896 		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
3897 		if (!p)
3898 			return nfserr_resource;
3899 		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
3900 		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
3901 						NFS4_VERIFIER_SIZE);
3902 	}
3903 	else if (nfserr == nfserr_clid_inuse) {
3904 		p = xdr_reserve_space(xdr, 8);
3905 		if (!p)
3906 			return nfserr_resource;
3907 		*p++ = cpu_to_be32(0);
3908 		*p++ = cpu_to_be32(0);
3909 	}
3910 	return nfserr;
3911 }
3912 
3913 static __be32
3914 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3915 {
3916 	struct xdr_stream *xdr = &resp->xdr;
3917 	__be32 *p;
3918 
3919 	if (!nfserr) {
3920 		p = xdr_reserve_space(xdr, 16);
3921 		if (!p)
3922 			return nfserr_resource;
3923 		*p++ = cpu_to_be32(write->wr_bytes_written);
3924 		*p++ = cpu_to_be32(write->wr_how_written);
3925 		p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
3926 							NFS4_VERIFIER_SIZE);
3927 	}
3928 	return nfserr;
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 	int status = 0;
3942 	uint64_t minor_id = 0;
3943 
3944 	if (nfserr)
3945 		return nfserr;
3946 
3947 	major_id = utsname()->nodename;
3948 	major_id_sz = strlen(major_id);
3949 	server_scope = utsname()->nodename;
3950 	server_scope_sz = strlen(server_scope);
3951 
3952 	p = xdr_reserve_space(xdr,
3953 		8 /* eir_clientid */ +
3954 		4 /* eir_sequenceid */ +
3955 		4 /* eir_flags */ +
3956 		4 /* spr_how */);
3957 	if (!p)
3958 		return nfserr_resource;
3959 
3960 	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
3961 	*p++ = cpu_to_be32(exid->seqid);
3962 	*p++ = cpu_to_be32(exid->flags);
3963 
3964 	*p++ = cpu_to_be32(exid->spa_how);
3965 
3966 	switch (exid->spa_how) {
3967 	case SP4_NONE:
3968 		break;
3969 	case SP4_MACH_CRED:
3970 		/* spo_must_enforce bitmap: */
3971 		status = nfsd4_encode_bitmap(xdr,
3972 					exid->spo_must_enforce[0],
3973 					exid->spo_must_enforce[1],
3974 					exid->spo_must_enforce[2]);
3975 		if (status)
3976 			goto out;
3977 		/* spo_must_allow bitmap: */
3978 		status = nfsd4_encode_bitmap(xdr,
3979 					exid->spo_must_allow[0],
3980 					exid->spo_must_allow[1],
3981 					exid->spo_must_allow[2]);
3982 		if (status)
3983 			goto out;
3984 		break;
3985 	default:
3986 		WARN_ON_ONCE(1);
3987 	}
3988 
3989 	p = xdr_reserve_space(xdr,
3990 		8 /* so_minor_id */ +
3991 		4 /* so_major_id.len */ +
3992 		(XDR_QUADLEN(major_id_sz) * 4) +
3993 		4 /* eir_server_scope.len */ +
3994 		(XDR_QUADLEN(server_scope_sz) * 4) +
3995 		4 /* eir_server_impl_id.count (0) */);
3996 	if (!p)
3997 		return nfserr_resource;
3998 
3999 	/* The server_owner struct */
4000 	p = xdr_encode_hyper(p, minor_id);      /* Minor id */
4001 	/* major id */
4002 	p = xdr_encode_opaque(p, major_id, major_id_sz);
4003 
4004 	/* Server scope */
4005 	p = xdr_encode_opaque(p, server_scope, server_scope_sz);
4006 
4007 	/* Implementation id */
4008 	*p++ = cpu_to_be32(0);	/* zero length nfs_impl_id4 array */
4009 	return 0;
4010 out:
4011 	return status;
4012 }
4013 
4014 static __be32
4015 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
4016 			    struct nfsd4_create_session *sess)
4017 {
4018 	struct xdr_stream *xdr = &resp->xdr;
4019 	__be32 *p;
4020 
4021 	if (nfserr)
4022 		return nfserr;
4023 
4024 	p = xdr_reserve_space(xdr, 24);
4025 	if (!p)
4026 		return nfserr_resource;
4027 	p = xdr_encode_opaque_fixed(p, sess->sessionid.data,
4028 					NFS4_MAX_SESSIONID_LEN);
4029 	*p++ = cpu_to_be32(sess->seqid);
4030 	*p++ = cpu_to_be32(sess->flags);
4031 
4032 	p = xdr_reserve_space(xdr, 28);
4033 	if (!p)
4034 		return nfserr_resource;
4035 	*p++ = cpu_to_be32(0); /* headerpadsz */
4036 	*p++ = cpu_to_be32(sess->fore_channel.maxreq_sz);
4037 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_sz);
4038 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_cached);
4039 	*p++ = cpu_to_be32(sess->fore_channel.maxops);
4040 	*p++ = cpu_to_be32(sess->fore_channel.maxreqs);
4041 	*p++ = cpu_to_be32(sess->fore_channel.nr_rdma_attrs);
4042 
4043 	if (sess->fore_channel.nr_rdma_attrs) {
4044 		p = xdr_reserve_space(xdr, 4);
4045 		if (!p)
4046 			return nfserr_resource;
4047 		*p++ = cpu_to_be32(sess->fore_channel.rdma_attrs);
4048 	}
4049 
4050 	p = xdr_reserve_space(xdr, 28);
4051 	if (!p)
4052 		return nfserr_resource;
4053 	*p++ = cpu_to_be32(0); /* headerpadsz */
4054 	*p++ = cpu_to_be32(sess->back_channel.maxreq_sz);
4055 	*p++ = cpu_to_be32(sess->back_channel.maxresp_sz);
4056 	*p++ = cpu_to_be32(sess->back_channel.maxresp_cached);
4057 	*p++ = cpu_to_be32(sess->back_channel.maxops);
4058 	*p++ = cpu_to_be32(sess->back_channel.maxreqs);
4059 	*p++ = cpu_to_be32(sess->back_channel.nr_rdma_attrs);
4060 
4061 	if (sess->back_channel.nr_rdma_attrs) {
4062 		p = xdr_reserve_space(xdr, 4);
4063 		if (!p)
4064 			return nfserr_resource;
4065 		*p++ = cpu_to_be32(sess->back_channel.rdma_attrs);
4066 	}
4067 	return 0;
4068 }
4069 
4070 static __be32
4071 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
4072 		      struct nfsd4_sequence *seq)
4073 {
4074 	struct xdr_stream *xdr = &resp->xdr;
4075 	__be32 *p;
4076 
4077 	if (nfserr)
4078 		return nfserr;
4079 
4080 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 20);
4081 	if (!p)
4082 		return nfserr_resource;
4083 	p = xdr_encode_opaque_fixed(p, seq->sessionid.data,
4084 					NFS4_MAX_SESSIONID_LEN);
4085 	*p++ = cpu_to_be32(seq->seqid);
4086 	*p++ = cpu_to_be32(seq->slotid);
4087 	/* Note slotid's are numbered from zero: */
4088 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_highest_slotid */
4089 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_target_highest_slotid */
4090 	*p++ = cpu_to_be32(seq->status_flags);
4091 
4092 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
4093 	return 0;
4094 }
4095 
4096 static __be32
4097 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
4098 			  struct nfsd4_test_stateid *test_stateid)
4099 {
4100 	struct xdr_stream *xdr = &resp->xdr;
4101 	struct nfsd4_test_stateid_id *stateid, *next;
4102 	__be32 *p;
4103 
4104 	if (nfserr)
4105 		return nfserr;
4106 
4107 	p = xdr_reserve_space(xdr, 4 + (4 * test_stateid->ts_num_ids));
4108 	if (!p)
4109 		return nfserr_resource;
4110 	*p++ = htonl(test_stateid->ts_num_ids);
4111 
4112 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
4113 		*p++ = stateid->ts_id_status;
4114 	}
4115 
4116 	return nfserr;
4117 }
4118 
4119 #ifdef CONFIG_NFSD_PNFS
4120 static __be32
4121 nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
4122 		struct nfsd4_getdeviceinfo *gdev)
4123 {
4124 	struct xdr_stream *xdr = &resp->xdr;
4125 	const struct nfsd4_layout_ops *ops;
4126 	u32 starting_len = xdr->buf->len, needed_len;
4127 	__be32 *p;
4128 
4129 	dprintk("%s: err %d\n", __func__, be32_to_cpu(nfserr));
4130 	if (nfserr)
4131 		goto out;
4132 
4133 	nfserr = nfserr_resource;
4134 	p = xdr_reserve_space(xdr, 4);
4135 	if (!p)
4136 		goto out;
4137 
4138 	*p++ = cpu_to_be32(gdev->gd_layout_type);
4139 
4140 	/* If maxcount is 0 then just update notifications */
4141 	if (gdev->gd_maxcount != 0) {
4142 		ops = nfsd4_layout_ops[gdev->gd_layout_type];
4143 		nfserr = ops->encode_getdeviceinfo(xdr, gdev);
4144 		if (nfserr) {
4145 			/*
4146 			 * We don't bother to burden the layout drivers with
4147 			 * enforcing gd_maxcount, just tell the client to
4148 			 * come back with a bigger buffer if it's not enough.
4149 			 */
4150 			if (xdr->buf->len + 4 > gdev->gd_maxcount)
4151 				goto toosmall;
4152 			goto out;
4153 		}
4154 	}
4155 
4156 	nfserr = nfserr_resource;
4157 	if (gdev->gd_notify_types) {
4158 		p = xdr_reserve_space(xdr, 4 + 4);
4159 		if (!p)
4160 			goto out;
4161 		*p++ = cpu_to_be32(1);			/* bitmap length */
4162 		*p++ = cpu_to_be32(gdev->gd_notify_types);
4163 	} else {
4164 		p = xdr_reserve_space(xdr, 4);
4165 		if (!p)
4166 			goto out;
4167 		*p++ = 0;
4168 	}
4169 
4170 	nfserr = 0;
4171 out:
4172 	kfree(gdev->gd_device);
4173 	dprintk("%s: done: %d\n", __func__, be32_to_cpu(nfserr));
4174 	return nfserr;
4175 
4176 toosmall:
4177 	dprintk("%s: maxcount too small\n", __func__);
4178 	needed_len = xdr->buf->len + 4 /* notifications */;
4179 	xdr_truncate_encode(xdr, starting_len);
4180 	p = xdr_reserve_space(xdr, 4);
4181 	if (!p) {
4182 		nfserr = nfserr_resource;
4183 	} else {
4184 		*p++ = cpu_to_be32(needed_len);
4185 		nfserr = nfserr_toosmall;
4186 	}
4187 	goto out;
4188 }
4189 
4190 static __be32
4191 nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr,
4192 		struct nfsd4_layoutget *lgp)
4193 {
4194 	struct xdr_stream *xdr = &resp->xdr;
4195 	const struct nfsd4_layout_ops *ops;
4196 	__be32 *p;
4197 
4198 	dprintk("%s: err %d\n", __func__, nfserr);
4199 	if (nfserr)
4200 		goto out;
4201 
4202 	nfserr = nfserr_resource;
4203 	p = xdr_reserve_space(xdr, 36 + sizeof(stateid_opaque_t));
4204 	if (!p)
4205 		goto out;
4206 
4207 	*p++ = cpu_to_be32(1);	/* we always set return-on-close */
4208 	*p++ = cpu_to_be32(lgp->lg_sid.si_generation);
4209 	p = xdr_encode_opaque_fixed(p, &lgp->lg_sid.si_opaque,
4210 				    sizeof(stateid_opaque_t));
4211 
4212 	*p++ = cpu_to_be32(1);	/* we always return a single layout */
4213 	p = xdr_encode_hyper(p, lgp->lg_seg.offset);
4214 	p = xdr_encode_hyper(p, lgp->lg_seg.length);
4215 	*p++ = cpu_to_be32(lgp->lg_seg.iomode);
4216 	*p++ = cpu_to_be32(lgp->lg_layout_type);
4217 
4218 	ops = nfsd4_layout_ops[lgp->lg_layout_type];
4219 	nfserr = ops->encode_layoutget(xdr, lgp);
4220 out:
4221 	kfree(lgp->lg_content);
4222 	return nfserr;
4223 }
4224 
4225 static __be32
4226 nfsd4_encode_layoutcommit(struct nfsd4_compoundres *resp, __be32 nfserr,
4227 			  struct nfsd4_layoutcommit *lcp)
4228 {
4229 	struct xdr_stream *xdr = &resp->xdr;
4230 	__be32 *p;
4231 
4232 	if (nfserr)
4233 		return nfserr;
4234 
4235 	p = xdr_reserve_space(xdr, 4);
4236 	if (!p)
4237 		return nfserr_resource;
4238 	*p++ = cpu_to_be32(lcp->lc_size_chg);
4239 	if (lcp->lc_size_chg) {
4240 		p = xdr_reserve_space(xdr, 8);
4241 		if (!p)
4242 			return nfserr_resource;
4243 		p = xdr_encode_hyper(p, lcp->lc_newsize);
4244 	}
4245 
4246 	return nfs_ok;
4247 }
4248 
4249 static __be32
4250 nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
4251 		struct nfsd4_layoutreturn *lrp)
4252 {
4253 	struct xdr_stream *xdr = &resp->xdr;
4254 	__be32 *p;
4255 
4256 	if (nfserr)
4257 		return nfserr;
4258 
4259 	p = xdr_reserve_space(xdr, 4);
4260 	if (!p)
4261 		return nfserr_resource;
4262 	*p++ = cpu_to_be32(lrp->lrs_present);
4263 	if (lrp->lrs_present)
4264 		return nfsd4_encode_stateid(xdr, &lrp->lr_sid);
4265 	return nfs_ok;
4266 }
4267 #endif /* CONFIG_NFSD_PNFS */
4268 
4269 static __be32
4270 nfsd42_encode_write_res(struct nfsd4_compoundres *resp, struct nfsd42_write_res *write)
4271 {
4272 	__be32 *p;
4273 
4274 	p = xdr_reserve_space(&resp->xdr, 4 + 8 + 4 + NFS4_VERIFIER_SIZE);
4275 	if (!p)
4276 		return nfserr_resource;
4277 
4278 	*p++ = cpu_to_be32(0);
4279 	p = xdr_encode_hyper(p, write->wr_bytes_written);
4280 	*p++ = cpu_to_be32(write->wr_stable_how);
4281 	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
4282 				    NFS4_VERIFIER_SIZE);
4283 	return nfs_ok;
4284 }
4285 
4286 static __be32
4287 nfsd4_encode_copy(struct nfsd4_compoundres *resp, __be32 nfserr,
4288 		  struct nfsd4_copy *copy)
4289 {
4290 	__be32 *p;
4291 
4292 	if (!nfserr) {
4293 		nfserr = nfsd42_encode_write_res(resp, &copy->cp_res);
4294 		if (nfserr)
4295 			return nfserr;
4296 
4297 		p = xdr_reserve_space(&resp->xdr, 4 + 4);
4298 		*p++ = cpu_to_be32(copy->cp_consecutive);
4299 		*p++ = cpu_to_be32(copy->cp_synchronous);
4300 	}
4301 	return nfserr;
4302 }
4303 
4304 static __be32
4305 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
4306 		  struct nfsd4_seek *seek)
4307 {
4308 	__be32 *p;
4309 
4310 	if (nfserr)
4311 		return nfserr;
4312 
4313 	p = xdr_reserve_space(&resp->xdr, 4 + 8);
4314 	*p++ = cpu_to_be32(seek->seek_eof);
4315 	p = xdr_encode_hyper(p, seek->seek_pos);
4316 
4317 	return nfserr;
4318 }
4319 
4320 static __be32
4321 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
4322 {
4323 	return nfserr;
4324 }
4325 
4326 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
4327 
4328 /*
4329  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
4330  * since we don't need to filter out obsolete ops as this is
4331  * done in the decoding phase.
4332  */
4333 static nfsd4_enc nfsd4_enc_ops[] = {
4334 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
4335 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
4336 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
4337 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
4338 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
4339 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4340 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
4341 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
4342 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
4343 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
4344 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
4345 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
4346 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
4347 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
4348 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4349 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
4350 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
4351 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
4352 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
4353 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4354 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
4355 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4356 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
4357 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
4358 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
4359 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
4360 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
4361 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
4362 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
4363 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
4364 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
4365 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
4366 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
4367 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
4368 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4369 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
4370 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
4371 
4372 	/* NFSv4.1 operations */
4373 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
4374 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
4375 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
4376 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
4377 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
4378 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
4379 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4380 #ifdef CONFIG_NFSD_PNFS
4381 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_getdeviceinfo,
4382 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4383 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_layoutcommit,
4384 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_layoutget,
4385 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_layoutreturn,
4386 #else
4387 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
4388 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4389 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
4390 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
4391 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4392 #endif
4393 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
4394 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
4395 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
4396 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
4397 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4398 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
4399 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
4400 
4401 	/* NFSv4.2 operations */
4402 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4403 	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_copy,
4404 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
4405 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4406 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
4407 	[OP_LAYOUTERROR]	= (nfsd4_enc)nfsd4_encode_noop,
4408 	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,
4409 	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,
4410 	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_noop,
4411 	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_noop,
4412 	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,
4413 	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,
4414 	[OP_CLONE]		= (nfsd4_enc)nfsd4_encode_noop,
4415 };
4416 
4417 /*
4418  * Calculate whether we still have space to encode repsize bytes.
4419  * There are two considerations:
4420  *     - For NFS versions >=4.1, the size of the reply must stay within
4421  *       session limits
4422  *     - For all NFS versions, we must stay within limited preallocated
4423  *       buffer space.
4424  *
4425  * This is called before the operation is processed, so can only provide
4426  * an upper estimate.  For some nonidempotent operations (such as
4427  * getattr), it's not necessarily a problem if that estimate is wrong,
4428  * as we can fail it after processing without significant side effects.
4429  */
4430 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
4431 {
4432 	struct xdr_buf *buf = &resp->rqstp->rq_res;
4433 	struct nfsd4_slot *slot = resp->cstate.slot;
4434 
4435 	if (buf->len + respsize <= buf->buflen)
4436 		return nfs_ok;
4437 	if (!nfsd4_has_session(&resp->cstate))
4438 		return nfserr_resource;
4439 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
4440 		WARN_ON_ONCE(1);
4441 		return nfserr_rep_too_big_to_cache;
4442 	}
4443 	return nfserr_rep_too_big;
4444 }
4445 
4446 void
4447 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
4448 {
4449 	struct xdr_stream *xdr = &resp->xdr;
4450 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
4451 	struct svc_rqst *rqstp = resp->rqstp;
4452 	int post_err_offset;
4453 	nfsd4_enc encoder;
4454 	__be32 *p;
4455 
4456 	p = xdr_reserve_space(xdr, 8);
4457 	if (!p) {
4458 		WARN_ON_ONCE(1);
4459 		return;
4460 	}
4461 	*p++ = cpu_to_be32(op->opnum);
4462 	post_err_offset = xdr->buf->len;
4463 
4464 	if (op->opnum == OP_ILLEGAL)
4465 		goto status;
4466 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
4467 	       !nfsd4_enc_ops[op->opnum]);
4468 	encoder = nfsd4_enc_ops[op->opnum];
4469 	op->status = encoder(resp, op->status, &op->u);
4470 	xdr_commit_encode(xdr);
4471 
4472 	/* nfsd4_check_resp_size guarantees enough room for error status */
4473 	if (!op->status) {
4474 		int space_needed = 0;
4475 		if (!nfsd4_last_compound_op(rqstp))
4476 			space_needed = COMPOUND_ERR_SLACK_SPACE;
4477 		op->status = nfsd4_check_resp_size(resp, space_needed);
4478 	}
4479 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
4480 		struct nfsd4_slot *slot = resp->cstate.slot;
4481 
4482 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
4483 			op->status = nfserr_rep_too_big_to_cache;
4484 		else
4485 			op->status = nfserr_rep_too_big;
4486 	}
4487 	if (op->status == nfserr_resource ||
4488 	    op->status == nfserr_rep_too_big ||
4489 	    op->status == nfserr_rep_too_big_to_cache) {
4490 		/*
4491 		 * The operation may have already been encoded or
4492 		 * partially encoded.  No op returns anything additional
4493 		 * in the case of one of these three errors, so we can
4494 		 * just truncate back to after the status.  But it's a
4495 		 * bug if we had to do this on a non-idempotent op:
4496 		 */
4497 		warn_on_nonidempotent_op(op);
4498 		xdr_truncate_encode(xdr, post_err_offset);
4499 	}
4500 	if (so) {
4501 		int len = xdr->buf->len - post_err_offset;
4502 
4503 		so->so_replay.rp_status = op->status;
4504 		so->so_replay.rp_buflen = len;
4505 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
4506 						so->so_replay.rp_buf, len);
4507 	}
4508 status:
4509 	/* Note that op->status is already in network byte order: */
4510 	write_bytes_to_xdr_buf(xdr->buf, post_err_offset - 4, &op->status, 4);
4511 }
4512 
4513 /*
4514  * Encode the reply stored in the stateowner reply cache
4515  *
4516  * XDR note: do not encode rp->rp_buflen: the buffer contains the
4517  * previously sent already encoded operation.
4518  */
4519 void
4520 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
4521 {
4522 	__be32 *p;
4523 	struct nfs4_replay *rp = op->replay;
4524 
4525 	BUG_ON(!rp);
4526 
4527 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
4528 	if (!p) {
4529 		WARN_ON_ONCE(1);
4530 		return;
4531 	}
4532 	*p++ = cpu_to_be32(op->opnum);
4533 	*p++ = rp->rp_status;  /* already xdr'ed */
4534 
4535 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
4536 }
4537 
4538 int
4539 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p)
4540 {
4541         return xdr_ressize_check(rqstp, p);
4542 }
4543 
4544 void nfsd4_release_compoundargs(struct svc_rqst *rqstp)
4545 {
4546 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4547 
4548 	if (args->ops != args->iops) {
4549 		kfree(args->ops);
4550 		args->ops = args->iops;
4551 	}
4552 	kfree(args->tmpp);
4553 	args->tmpp = NULL;
4554 	while (args->to_free) {
4555 		struct svcxdr_tmpbuf *tb = args->to_free;
4556 		args->to_free = tb->next;
4557 		kfree(tb);
4558 	}
4559 }
4560 
4561 int
4562 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p)
4563 {
4564 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4565 
4566 	if (rqstp->rq_arg.head[0].iov_len % 4) {
4567 		/* client is nuts */
4568 		dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)",
4569 			__func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid));
4570 		return 0;
4571 	}
4572 	args->p = p;
4573 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
4574 	args->pagelist = rqstp->rq_arg.pages;
4575 	args->pagelen = rqstp->rq_arg.page_len;
4576 	args->tmpp = NULL;
4577 	args->to_free = NULL;
4578 	args->ops = args->iops;
4579 	args->rqstp = rqstp;
4580 
4581 	return !nfsd4_decode_compound(args);
4582 }
4583 
4584 int
4585 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p)
4586 {
4587 	/*
4588 	 * All that remains is to write the tag and operation count...
4589 	 */
4590 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
4591 	struct xdr_buf *buf = resp->xdr.buf;
4592 
4593 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
4594 				 buf->tail[0].iov_len);
4595 
4596 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
4597 
4598 	p = resp->tagp;
4599 	*p++ = htonl(resp->taglen);
4600 	memcpy(p, resp->tag, resp->taglen);
4601 	p += XDR_QUADLEN(resp->taglen);
4602 	*p++ = htonl(resp->opcnt);
4603 
4604 	nfsd4_sequence_done(resp);
4605 	return 1;
4606 }
4607 
4608 /*
4609  * Local variables:
4610  *  c-basic-offset: 8
4611  * End:
4612  */
4613