xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision 9be08a27)
1 /*
2  *  Server-side XDR for NFSv4
3  *
4  *  Copyright (c) 2002 The Regents of the University of Michigan.
5  *  All rights reserved.
6  *
7  *  Kendrick Smith <kmsmith@umich.edu>
8  *  Andy Adamson   <andros@umich.edu>
9  *
10  *  Redistribution and use in source and binary forms, with or without
11  *  modification, are permitted provided that the following conditions
12  *  are met:
13  *
14  *  1. Redistributions of source code must retain the above copyright
15  *     notice, this list of conditions and the following disclaimer.
16  *  2. Redistributions in binary form must reproduce the above copyright
17  *     notice, this list of conditions and the following disclaimer in the
18  *     documentation and/or other materials provided with the distribution.
19  *  3. Neither the name of the University nor the names of its
20  *     contributors may be used to endorse or promote products derived
21  *     from this software without specific prior written permission.
22  *
23  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
24  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
30  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 #include <linux/file.h>
37 #include <linux/slab.h>
38 #include <linux/namei.h>
39 #include <linux/statfs.h>
40 #include <linux/utsname.h>
41 #include <linux/pagemap.h>
42 #include <linux/sunrpc/svcauth_gss.h>
43 
44 #include "idmap.h"
45 #include "acl.h"
46 #include "xdr4.h"
47 #include "vfs.h"
48 #include "state.h"
49 #include "cache.h"
50 #include "netns.h"
51 #include "pnfs.h"
52 
53 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
54 #include <linux/security.h>
55 #endif
56 
57 
58 #define NFSDDBG_FACILITY		NFSDDBG_XDR
59 
60 const u32 nfsd_suppattrs[3][3] = {
61 	{NFSD4_SUPPORTED_ATTRS_WORD0,
62 	 NFSD4_SUPPORTED_ATTRS_WORD1,
63 	 NFSD4_SUPPORTED_ATTRS_WORD2},
64 
65 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
66 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
67 	 NFSD4_1_SUPPORTED_ATTRS_WORD2},
68 
69 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
70 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
71 	 NFSD4_2_SUPPORTED_ATTRS_WORD2},
72 };
73 
74 /*
75  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
76  * directory in order to indicate to the client that a filesystem boundary is present
77  * We use a fixed fsid for a referral
78  */
79 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
80 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
81 
82 static __be32
83 check_filename(char *str, int len)
84 {
85 	int i;
86 
87 	if (len == 0)
88 		return nfserr_inval;
89 	if (isdotent(str, len))
90 		return nfserr_badname;
91 	for (i = 0; i < len; i++)
92 		if (str[i] == '/')
93 			return nfserr_badname;
94 	return 0;
95 }
96 
97 #define DECODE_HEAD				\
98 	__be32 *p;				\
99 	__be32 status
100 #define DECODE_TAIL				\
101 	status = 0;				\
102 out:						\
103 	return status;				\
104 xdr_error:					\
105 	dprintk("NFSD: xdr error (%s:%d)\n",	\
106 			__FILE__, __LINE__);	\
107 	status = nfserr_bad_xdr;		\
108 	goto out
109 
110 #define READMEM(x,nbytes) do {			\
111 	x = (char *)p;				\
112 	p += XDR_QUADLEN(nbytes);		\
113 } while (0)
114 #define SAVEMEM(x,nbytes) do {			\
115 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
116  		savemem(argp, p, nbytes) :	\
117  		(char *)p)) {			\
118 		dprintk("NFSD: xdr error (%s:%d)\n", \
119 				__FILE__, __LINE__); \
120 		goto xdr_error;			\
121 		}				\
122 	p += XDR_QUADLEN(nbytes);		\
123 } while (0)
124 #define COPYMEM(x,nbytes) do {			\
125 	memcpy((x), p, nbytes);			\
126 	p += XDR_QUADLEN(nbytes);		\
127 } while (0)
128 
129 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
130 #define READ_BUF(nbytes)  do {			\
131 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
132 		p = argp->p;			\
133 		argp->p += XDR_QUADLEN(nbytes);	\
134 	} else if (!(p = read_buf(argp, nbytes))) { \
135 		dprintk("NFSD: xdr error (%s:%d)\n", \
136 				__FILE__, __LINE__); \
137 		goto xdr_error;			\
138 	}					\
139 } while (0)
140 
141 static void next_decode_page(struct nfsd4_compoundargs *argp)
142 {
143 	argp->p = page_address(argp->pagelist[0]);
144 	argp->pagelist++;
145 	if (argp->pagelen < PAGE_SIZE) {
146 		argp->end = argp->p + XDR_QUADLEN(argp->pagelen);
147 		argp->pagelen = 0;
148 	} else {
149 		argp->end = argp->p + (PAGE_SIZE>>2);
150 		argp->pagelen -= PAGE_SIZE;
151 	}
152 }
153 
154 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
155 {
156 	/* We want more bytes than seem to be available.
157 	 * Maybe we need a new page, maybe we have just run out
158 	 */
159 	unsigned int avail = (char *)argp->end - (char *)argp->p;
160 	__be32 *p;
161 
162 	if (argp->pagelen == 0) {
163 		struct kvec *vec = &argp->rqstp->rq_arg.tail[0];
164 
165 		if (!argp->tail) {
166 			argp->tail = true;
167 			avail = vec->iov_len;
168 			argp->p = vec->iov_base;
169 			argp->end = vec->iov_base + avail;
170 		}
171 
172 		if (avail < nbytes)
173 			return NULL;
174 
175 		p = argp->p;
176 		argp->p += XDR_QUADLEN(nbytes);
177 		return p;
178 	}
179 
180 	if (avail + argp->pagelen < nbytes)
181 		return NULL;
182 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
183 		return NULL;
184 	/* ok, we can do it with the current plus the next page */
185 	if (nbytes <= sizeof(argp->tmp))
186 		p = argp->tmp;
187 	else {
188 		kfree(argp->tmpp);
189 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
190 		if (!p)
191 			return NULL;
192 
193 	}
194 	/*
195 	 * The following memcpy is safe because read_buf is always
196 	 * called with nbytes > avail, and the two cases above both
197 	 * guarantee p points to at least nbytes bytes.
198 	 */
199 	memcpy(p, argp->p, avail);
200 	next_decode_page(argp);
201 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
202 	argp->p += XDR_QUADLEN(nbytes - avail);
203 	return p;
204 }
205 
206 static int zero_clientid(clientid_t *clid)
207 {
208 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
209 }
210 
211 /**
212  * svcxdr_tmpalloc - allocate memory to be freed after compound processing
213  * @argp: NFSv4 compound argument structure
214  * @p: pointer to be freed (with kfree())
215  *
216  * Marks @p to be freed when processing the compound operation
217  * described in @argp finishes.
218  */
219 static void *
220 svcxdr_tmpalloc(struct nfsd4_compoundargs *argp, u32 len)
221 {
222 	struct svcxdr_tmpbuf *tb;
223 
224 	tb = kmalloc(sizeof(*tb) + len, GFP_KERNEL);
225 	if (!tb)
226 		return NULL;
227 	tb->next = argp->to_free;
228 	argp->to_free = tb;
229 	return tb->buf;
230 }
231 
232 /*
233  * For xdr strings that need to be passed to other kernel api's
234  * as null-terminated strings.
235  *
236  * Note null-terminating in place usually isn't safe since the
237  * buffer might end on a page boundary.
238  */
239 static char *
240 svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len)
241 {
242 	char *p = svcxdr_tmpalloc(argp, len + 1);
243 
244 	if (!p)
245 		return NULL;
246 	memcpy(p, buf, len);
247 	p[len] = '\0';
248 	return p;
249 }
250 
251 /**
252  * savemem - duplicate a chunk of memory for later processing
253  * @argp: NFSv4 compound argument structure to be freed with
254  * @p: pointer to be duplicated
255  * @nbytes: length to be duplicated
256  *
257  * Returns a pointer to a copy of @nbytes bytes of memory at @p
258  * that are preserved until processing of the NFSv4 compound
259  * operation described by @argp finishes.
260  */
261 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
262 {
263 	void *ret;
264 
265 	ret = svcxdr_tmpalloc(argp, nbytes);
266 	if (!ret)
267 		return NULL;
268 	memcpy(ret, p, nbytes);
269 	return ret;
270 }
271 
272 /*
273  * We require the high 32 bits of 'seconds' to be 0, and
274  * we ignore all 32 bits of 'nseconds'.
275  */
276 static __be32
277 nfsd4_decode_time(struct nfsd4_compoundargs *argp, struct timespec *tv)
278 {
279 	DECODE_HEAD;
280 	u64 sec;
281 
282 	READ_BUF(12);
283 	p = xdr_decode_hyper(p, &sec);
284 	tv->tv_sec = sec;
285 	tv->tv_nsec = be32_to_cpup(p++);
286 	if (tv->tv_nsec >= (u32)1000000000)
287 		return nfserr_inval;
288 
289 	DECODE_TAIL;
290 }
291 
292 static __be32
293 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
294 {
295 	u32 bmlen;
296 	DECODE_HEAD;
297 
298 	bmval[0] = 0;
299 	bmval[1] = 0;
300 	bmval[2] = 0;
301 
302 	READ_BUF(4);
303 	bmlen = be32_to_cpup(p++);
304 	if (bmlen > 1000)
305 		goto xdr_error;
306 
307 	READ_BUF(bmlen << 2);
308 	if (bmlen > 0)
309 		bmval[0] = be32_to_cpup(p++);
310 	if (bmlen > 1)
311 		bmval[1] = be32_to_cpup(p++);
312 	if (bmlen > 2)
313 		bmval[2] = be32_to_cpup(p++);
314 
315 	DECODE_TAIL;
316 }
317 
318 static __be32
319 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
320 		   struct iattr *iattr, struct nfs4_acl **acl,
321 		   struct xdr_netobj *label, int *umask)
322 {
323 	struct timespec ts;
324 	int expected_len, len = 0;
325 	u32 dummy32;
326 	char *buf;
327 
328 	DECODE_HEAD;
329 	iattr->ia_valid = 0;
330 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
331 		return status;
332 
333 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
334 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
335 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2) {
336 		if (nfsd_attrs_supported(argp->minorversion, bmval))
337 			return nfserr_inval;
338 		return nfserr_attrnotsupp;
339 	}
340 
341 	READ_BUF(4);
342 	expected_len = be32_to_cpup(p++);
343 
344 	if (bmval[0] & FATTR4_WORD0_SIZE) {
345 		READ_BUF(8);
346 		len += 8;
347 		p = xdr_decode_hyper(p, &iattr->ia_size);
348 		iattr->ia_valid |= ATTR_SIZE;
349 	}
350 	if (bmval[0] & FATTR4_WORD0_ACL) {
351 		u32 nace;
352 		struct nfs4_ace *ace;
353 
354 		READ_BUF(4); len += 4;
355 		nace = be32_to_cpup(p++);
356 
357 		if (nace > NFS4_ACL_MAX)
358 			return nfserr_fbig;
359 
360 		*acl = svcxdr_tmpalloc(argp, nfs4_acl_bytes(nace));
361 		if (*acl == NULL)
362 			return nfserr_jukebox;
363 
364 		(*acl)->naces = nace;
365 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
366 			READ_BUF(16); len += 16;
367 			ace->type = be32_to_cpup(p++);
368 			ace->flag = be32_to_cpup(p++);
369 			ace->access_mask = be32_to_cpup(p++);
370 			dummy32 = be32_to_cpup(p++);
371 			READ_BUF(dummy32);
372 			len += XDR_QUADLEN(dummy32) << 2;
373 			READMEM(buf, dummy32);
374 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
375 			status = nfs_ok;
376 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
377 				;
378 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
379 				status = nfsd_map_name_to_gid(argp->rqstp,
380 						buf, dummy32, &ace->who_gid);
381 			else
382 				status = nfsd_map_name_to_uid(argp->rqstp,
383 						buf, dummy32, &ace->who_uid);
384 			if (status)
385 				return status;
386 		}
387 	} else
388 		*acl = NULL;
389 	if (bmval[1] & FATTR4_WORD1_MODE) {
390 		READ_BUF(4);
391 		len += 4;
392 		iattr->ia_mode = be32_to_cpup(p++);
393 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
394 		iattr->ia_valid |= ATTR_MODE;
395 	}
396 	if (bmval[1] & FATTR4_WORD1_OWNER) {
397 		READ_BUF(4);
398 		len += 4;
399 		dummy32 = be32_to_cpup(p++);
400 		READ_BUF(dummy32);
401 		len += (XDR_QUADLEN(dummy32) << 2);
402 		READMEM(buf, dummy32);
403 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
404 			return status;
405 		iattr->ia_valid |= ATTR_UID;
406 	}
407 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
408 		READ_BUF(4);
409 		len += 4;
410 		dummy32 = be32_to_cpup(p++);
411 		READ_BUF(dummy32);
412 		len += (XDR_QUADLEN(dummy32) << 2);
413 		READMEM(buf, dummy32);
414 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
415 			return status;
416 		iattr->ia_valid |= ATTR_GID;
417 	}
418 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
419 		READ_BUF(4);
420 		len += 4;
421 		dummy32 = be32_to_cpup(p++);
422 		switch (dummy32) {
423 		case NFS4_SET_TO_CLIENT_TIME:
424 			len += 12;
425 			status = nfsd4_decode_time(argp, &ts);
426 			iattr->ia_atime = timespec_to_timespec64(ts);
427 			if (status)
428 				return status;
429 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
430 			break;
431 		case NFS4_SET_TO_SERVER_TIME:
432 			iattr->ia_valid |= ATTR_ATIME;
433 			break;
434 		default:
435 			goto xdr_error;
436 		}
437 	}
438 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
439 		READ_BUF(4);
440 		len += 4;
441 		dummy32 = be32_to_cpup(p++);
442 		switch (dummy32) {
443 		case NFS4_SET_TO_CLIENT_TIME:
444 			len += 12;
445 			status = nfsd4_decode_time(argp, &ts);
446 			iattr->ia_mtime = timespec_to_timespec64(ts);
447 			if (status)
448 				return status;
449 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
450 			break;
451 		case NFS4_SET_TO_SERVER_TIME:
452 			iattr->ia_valid |= ATTR_MTIME;
453 			break;
454 		default:
455 			goto xdr_error;
456 		}
457 	}
458 
459 	label->len = 0;
460 	if (IS_ENABLED(CONFIG_NFSD_V4_SECURITY_LABEL) &&
461 	    bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
462 		READ_BUF(4);
463 		len += 4;
464 		dummy32 = be32_to_cpup(p++); /* lfs: we don't use it */
465 		READ_BUF(4);
466 		len += 4;
467 		dummy32 = be32_to_cpup(p++); /* pi: we don't use it either */
468 		READ_BUF(4);
469 		len += 4;
470 		dummy32 = be32_to_cpup(p++);
471 		READ_BUF(dummy32);
472 		if (dummy32 > NFS4_MAXLABELLEN)
473 			return nfserr_badlabel;
474 		len += (XDR_QUADLEN(dummy32) << 2);
475 		READMEM(buf, dummy32);
476 		label->len = dummy32;
477 		label->data = svcxdr_dupstr(argp, buf, dummy32);
478 		if (!label->data)
479 			return nfserr_jukebox;
480 	}
481 	if (bmval[2] & FATTR4_WORD2_MODE_UMASK) {
482 		if (!umask)
483 			goto xdr_error;
484 		READ_BUF(8);
485 		len += 8;
486 		dummy32 = be32_to_cpup(p++);
487 		iattr->ia_mode = dummy32 & (S_IFMT | S_IALLUGO);
488 		dummy32 = be32_to_cpup(p++);
489 		*umask = dummy32 & S_IRWXUGO;
490 		iattr->ia_valid |= ATTR_MODE;
491 	}
492 	if (len != expected_len)
493 		goto xdr_error;
494 
495 	DECODE_TAIL;
496 }
497 
498 static __be32
499 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
500 {
501 	DECODE_HEAD;
502 
503 	READ_BUF(sizeof(stateid_t));
504 	sid->si_generation = be32_to_cpup(p++);
505 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
506 
507 	DECODE_TAIL;
508 }
509 
510 static __be32
511 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
512 {
513 	DECODE_HEAD;
514 
515 	READ_BUF(4);
516 	access->ac_req_access = be32_to_cpup(p++);
517 
518 	DECODE_TAIL;
519 }
520 
521 static __be32 nfsd4_decode_cb_sec(struct nfsd4_compoundargs *argp, struct nfsd4_cb_sec *cbs)
522 {
523 	DECODE_HEAD;
524 	u32 dummy, uid, gid;
525 	char *machine_name;
526 	int i;
527 	int nr_secflavs;
528 
529 	/* callback_sec_params4 */
530 	READ_BUF(4);
531 	nr_secflavs = be32_to_cpup(p++);
532 	if (nr_secflavs)
533 		cbs->flavor = (u32)(-1);
534 	else
535 		/* Is this legal? Be generous, take it to mean AUTH_NONE: */
536 		cbs->flavor = 0;
537 	for (i = 0; i < nr_secflavs; ++i) {
538 		READ_BUF(4);
539 		dummy = be32_to_cpup(p++);
540 		switch (dummy) {
541 		case RPC_AUTH_NULL:
542 			/* Nothing to read */
543 			if (cbs->flavor == (u32)(-1))
544 				cbs->flavor = RPC_AUTH_NULL;
545 			break;
546 		case RPC_AUTH_UNIX:
547 			READ_BUF(8);
548 			/* stamp */
549 			dummy = be32_to_cpup(p++);
550 
551 			/* machine name */
552 			dummy = be32_to_cpup(p++);
553 			READ_BUF(dummy);
554 			SAVEMEM(machine_name, dummy);
555 
556 			/* uid, gid */
557 			READ_BUF(8);
558 			uid = be32_to_cpup(p++);
559 			gid = be32_to_cpup(p++);
560 
561 			/* more gids */
562 			READ_BUF(4);
563 			dummy = be32_to_cpup(p++);
564 			READ_BUF(dummy * 4);
565 			if (cbs->flavor == (u32)(-1)) {
566 				kuid_t kuid = make_kuid(&init_user_ns, uid);
567 				kgid_t kgid = make_kgid(&init_user_ns, gid);
568 				if (uid_valid(kuid) && gid_valid(kgid)) {
569 					cbs->uid = kuid;
570 					cbs->gid = kgid;
571 					cbs->flavor = RPC_AUTH_UNIX;
572 				} else {
573 					dprintk("RPC_AUTH_UNIX with invalid"
574 						"uid or gid ignoring!\n");
575 				}
576 			}
577 			break;
578 		case RPC_AUTH_GSS:
579 			dprintk("RPC_AUTH_GSS callback secflavor "
580 				"not supported!\n");
581 			READ_BUF(8);
582 			/* gcbp_service */
583 			dummy = be32_to_cpup(p++);
584 			/* gcbp_handle_from_server */
585 			dummy = be32_to_cpup(p++);
586 			READ_BUF(dummy);
587 			p += XDR_QUADLEN(dummy);
588 			/* gcbp_handle_from_client */
589 			READ_BUF(4);
590 			dummy = be32_to_cpup(p++);
591 			READ_BUF(dummy);
592 			break;
593 		default:
594 			dprintk("Illegal callback secflavor\n");
595 			return nfserr_inval;
596 		}
597 	}
598 	DECODE_TAIL;
599 }
600 
601 static __be32 nfsd4_decode_backchannel_ctl(struct nfsd4_compoundargs *argp, struct nfsd4_backchannel_ctl *bc)
602 {
603 	DECODE_HEAD;
604 
605 	READ_BUF(4);
606 	bc->bc_cb_program = be32_to_cpup(p++);
607 	nfsd4_decode_cb_sec(argp, &bc->bc_cb_sec);
608 
609 	DECODE_TAIL;
610 }
611 
612 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
613 {
614 	DECODE_HEAD;
615 
616 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
617 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
618 	bcts->dir = be32_to_cpup(p++);
619 	/* XXX: skipping ctsa_use_conn_in_rdma_mode.  Perhaps Tom Tucker
620 	 * could help us figure out we should be using it. */
621 	DECODE_TAIL;
622 }
623 
624 static __be32
625 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
626 {
627 	DECODE_HEAD;
628 
629 	READ_BUF(4);
630 	close->cl_seqid = be32_to_cpup(p++);
631 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
632 
633 	DECODE_TAIL;
634 }
635 
636 
637 static __be32
638 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
639 {
640 	DECODE_HEAD;
641 
642 	READ_BUF(12);
643 	p = xdr_decode_hyper(p, &commit->co_offset);
644 	commit->co_count = be32_to_cpup(p++);
645 
646 	DECODE_TAIL;
647 }
648 
649 static __be32
650 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
651 {
652 	DECODE_HEAD;
653 
654 	READ_BUF(4);
655 	create->cr_type = be32_to_cpup(p++);
656 	switch (create->cr_type) {
657 	case NF4LNK:
658 		READ_BUF(4);
659 		create->cr_datalen = be32_to_cpup(p++);
660 		READ_BUF(create->cr_datalen);
661 		create->cr_data = svcxdr_dupstr(argp, p, create->cr_datalen);
662 		if (!create->cr_data)
663 			return nfserr_jukebox;
664 		break;
665 	case NF4BLK:
666 	case NF4CHR:
667 		READ_BUF(8);
668 		create->cr_specdata1 = be32_to_cpup(p++);
669 		create->cr_specdata2 = be32_to_cpup(p++);
670 		break;
671 	case NF4SOCK:
672 	case NF4FIFO:
673 	case NF4DIR:
674 	default:
675 		break;
676 	}
677 
678 	READ_BUF(4);
679 	create->cr_namelen = be32_to_cpup(p++);
680 	READ_BUF(create->cr_namelen);
681 	SAVEMEM(create->cr_name, create->cr_namelen);
682 	if ((status = check_filename(create->cr_name, create->cr_namelen)))
683 		return status;
684 
685 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
686 				    &create->cr_acl, &create->cr_label,
687 				    &create->cr_umask);
688 	if (status)
689 		goto out;
690 
691 	DECODE_TAIL;
692 }
693 
694 static inline __be32
695 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
696 {
697 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
698 }
699 
700 static inline __be32
701 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
702 {
703 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
704 }
705 
706 static __be32
707 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
708 {
709 	DECODE_HEAD;
710 
711 	READ_BUF(4);
712 	link->li_namelen = be32_to_cpup(p++);
713 	READ_BUF(link->li_namelen);
714 	SAVEMEM(link->li_name, link->li_namelen);
715 	if ((status = check_filename(link->li_name, link->li_namelen)))
716 		return status;
717 
718 	DECODE_TAIL;
719 }
720 
721 static __be32
722 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
723 {
724 	DECODE_HEAD;
725 
726 	/*
727 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
728 	*/
729 	READ_BUF(28);
730 	lock->lk_type = be32_to_cpup(p++);
731 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
732 		goto xdr_error;
733 	lock->lk_reclaim = be32_to_cpup(p++);
734 	p = xdr_decode_hyper(p, &lock->lk_offset);
735 	p = xdr_decode_hyper(p, &lock->lk_length);
736 	lock->lk_is_new = be32_to_cpup(p++);
737 
738 	if (lock->lk_is_new) {
739 		READ_BUF(4);
740 		lock->lk_new_open_seqid = be32_to_cpup(p++);
741 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
742 		if (status)
743 			return status;
744 		READ_BUF(8 + sizeof(clientid_t));
745 		lock->lk_new_lock_seqid = be32_to_cpup(p++);
746 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
747 		lock->lk_new_owner.len = be32_to_cpup(p++);
748 		READ_BUF(lock->lk_new_owner.len);
749 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
750 	} else {
751 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
752 		if (status)
753 			return status;
754 		READ_BUF(4);
755 		lock->lk_old_lock_seqid = be32_to_cpup(p++);
756 	}
757 
758 	DECODE_TAIL;
759 }
760 
761 static __be32
762 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
763 {
764 	DECODE_HEAD;
765 
766 	READ_BUF(32);
767 	lockt->lt_type = be32_to_cpup(p++);
768 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
769 		goto xdr_error;
770 	p = xdr_decode_hyper(p, &lockt->lt_offset);
771 	p = xdr_decode_hyper(p, &lockt->lt_length);
772 	COPYMEM(&lockt->lt_clientid, 8);
773 	lockt->lt_owner.len = be32_to_cpup(p++);
774 	READ_BUF(lockt->lt_owner.len);
775 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
776 
777 	DECODE_TAIL;
778 }
779 
780 static __be32
781 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
782 {
783 	DECODE_HEAD;
784 
785 	READ_BUF(8);
786 	locku->lu_type = be32_to_cpup(p++);
787 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
788 		goto xdr_error;
789 	locku->lu_seqid = be32_to_cpup(p++);
790 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
791 	if (status)
792 		return status;
793 	READ_BUF(16);
794 	p = xdr_decode_hyper(p, &locku->lu_offset);
795 	p = xdr_decode_hyper(p, &locku->lu_length);
796 
797 	DECODE_TAIL;
798 }
799 
800 static __be32
801 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
802 {
803 	DECODE_HEAD;
804 
805 	READ_BUF(4);
806 	lookup->lo_len = be32_to_cpup(p++);
807 	READ_BUF(lookup->lo_len);
808 	SAVEMEM(lookup->lo_name, lookup->lo_len);
809 	if ((status = check_filename(lookup->lo_name, lookup->lo_len)))
810 		return status;
811 
812 	DECODE_TAIL;
813 }
814 
815 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
816 {
817 	__be32 *p;
818 	u32 w;
819 
820 	READ_BUF(4);
821 	w = be32_to_cpup(p++);
822 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
823 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
824 	if (deleg_when)
825 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
826 
827 	switch (w & NFS4_SHARE_ACCESS_MASK) {
828 	case NFS4_SHARE_ACCESS_READ:
829 	case NFS4_SHARE_ACCESS_WRITE:
830 	case NFS4_SHARE_ACCESS_BOTH:
831 		break;
832 	default:
833 		return nfserr_bad_xdr;
834 	}
835 	w &= ~NFS4_SHARE_ACCESS_MASK;
836 	if (!w)
837 		return nfs_ok;
838 	if (!argp->minorversion)
839 		return nfserr_bad_xdr;
840 	switch (w & NFS4_SHARE_WANT_MASK) {
841 	case NFS4_SHARE_WANT_NO_PREFERENCE:
842 	case NFS4_SHARE_WANT_READ_DELEG:
843 	case NFS4_SHARE_WANT_WRITE_DELEG:
844 	case NFS4_SHARE_WANT_ANY_DELEG:
845 	case NFS4_SHARE_WANT_NO_DELEG:
846 	case NFS4_SHARE_WANT_CANCEL:
847 		break;
848 	default:
849 		return nfserr_bad_xdr;
850 	}
851 	w &= ~NFS4_SHARE_WANT_MASK;
852 	if (!w)
853 		return nfs_ok;
854 
855 	if (!deleg_when)	/* open_downgrade */
856 		return nfserr_inval;
857 	switch (w) {
858 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
859 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
860 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
861 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
862 		return nfs_ok;
863 	}
864 xdr_error:
865 	return nfserr_bad_xdr;
866 }
867 
868 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
869 {
870 	__be32 *p;
871 
872 	READ_BUF(4);
873 	*x = be32_to_cpup(p++);
874 	/* Note: unlinke access bits, deny bits may be zero. */
875 	if (*x & ~NFS4_SHARE_DENY_BOTH)
876 		return nfserr_bad_xdr;
877 	return nfs_ok;
878 xdr_error:
879 	return nfserr_bad_xdr;
880 }
881 
882 static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
883 {
884 	__be32 *p;
885 
886 	READ_BUF(4);
887 	o->len = be32_to_cpup(p++);
888 
889 	if (o->len == 0 || o->len > NFS4_OPAQUE_LIMIT)
890 		return nfserr_bad_xdr;
891 
892 	READ_BUF(o->len);
893 	SAVEMEM(o->data, o->len);
894 	return nfs_ok;
895 xdr_error:
896 	return nfserr_bad_xdr;
897 }
898 
899 static __be32
900 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
901 {
902 	DECODE_HEAD;
903 	u32 dummy;
904 
905 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
906 	open->op_iattr.ia_valid = 0;
907 	open->op_openowner = NULL;
908 
909 	open->op_xdr_error = 0;
910 	/* seqid, share_access, share_deny, clientid, ownerlen */
911 	READ_BUF(4);
912 	open->op_seqid = be32_to_cpup(p++);
913 	/* decode, yet ignore deleg_when until supported */
914 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
915 					   &open->op_deleg_want, &dummy);
916 	if (status)
917 		goto xdr_error;
918 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
919 	if (status)
920 		goto xdr_error;
921 	READ_BUF(sizeof(clientid_t));
922 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
923 	status = nfsd4_decode_opaque(argp, &open->op_owner);
924 	if (status)
925 		goto xdr_error;
926 	READ_BUF(4);
927 	open->op_create = be32_to_cpup(p++);
928 	switch (open->op_create) {
929 	case NFS4_OPEN_NOCREATE:
930 		break;
931 	case NFS4_OPEN_CREATE:
932 		READ_BUF(4);
933 		open->op_createmode = be32_to_cpup(p++);
934 		switch (open->op_createmode) {
935 		case NFS4_CREATE_UNCHECKED:
936 		case NFS4_CREATE_GUARDED:
937 			status = nfsd4_decode_fattr(argp, open->op_bmval,
938 				&open->op_iattr, &open->op_acl, &open->op_label,
939 				&open->op_umask);
940 			if (status)
941 				goto out;
942 			break;
943 		case NFS4_CREATE_EXCLUSIVE:
944 			READ_BUF(NFS4_VERIFIER_SIZE);
945 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
946 			break;
947 		case NFS4_CREATE_EXCLUSIVE4_1:
948 			if (argp->minorversion < 1)
949 				goto xdr_error;
950 			READ_BUF(NFS4_VERIFIER_SIZE);
951 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
952 			status = nfsd4_decode_fattr(argp, open->op_bmval,
953 				&open->op_iattr, &open->op_acl, &open->op_label,
954 				&open->op_umask);
955 			if (status)
956 				goto out;
957 			break;
958 		default:
959 			goto xdr_error;
960 		}
961 		break;
962 	default:
963 		goto xdr_error;
964 	}
965 
966 	/* open_claim */
967 	READ_BUF(4);
968 	open->op_claim_type = be32_to_cpup(p++);
969 	switch (open->op_claim_type) {
970 	case NFS4_OPEN_CLAIM_NULL:
971 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
972 		READ_BUF(4);
973 		open->op_fname.len = be32_to_cpup(p++);
974 		READ_BUF(open->op_fname.len);
975 		SAVEMEM(open->op_fname.data, open->op_fname.len);
976 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
977 			return status;
978 		break;
979 	case NFS4_OPEN_CLAIM_PREVIOUS:
980 		READ_BUF(4);
981 		open->op_delegate_type = be32_to_cpup(p++);
982 		break;
983 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
984 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
985 		if (status)
986 			return status;
987 		READ_BUF(4);
988 		open->op_fname.len = be32_to_cpup(p++);
989 		READ_BUF(open->op_fname.len);
990 		SAVEMEM(open->op_fname.data, open->op_fname.len);
991 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
992 			return status;
993 		break;
994 	case NFS4_OPEN_CLAIM_FH:
995 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
996 		if (argp->minorversion < 1)
997 			goto xdr_error;
998 		/* void */
999 		break;
1000 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
1001 		if (argp->minorversion < 1)
1002 			goto xdr_error;
1003 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
1004 		if (status)
1005 			return status;
1006 		break;
1007 	default:
1008 		goto xdr_error;
1009 	}
1010 
1011 	DECODE_TAIL;
1012 }
1013 
1014 static __be32
1015 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
1016 {
1017 	DECODE_HEAD;
1018 
1019 	if (argp->minorversion >= 1)
1020 		return nfserr_notsupp;
1021 
1022 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
1023 	if (status)
1024 		return status;
1025 	READ_BUF(4);
1026 	open_conf->oc_seqid = be32_to_cpup(p++);
1027 
1028 	DECODE_TAIL;
1029 }
1030 
1031 static __be32
1032 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
1033 {
1034 	DECODE_HEAD;
1035 
1036 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
1037 	if (status)
1038 		return status;
1039 	READ_BUF(4);
1040 	open_down->od_seqid = be32_to_cpup(p++);
1041 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
1042 					   &open_down->od_deleg_want, NULL);
1043 	if (status)
1044 		return status;
1045 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
1046 	if (status)
1047 		return status;
1048 	DECODE_TAIL;
1049 }
1050 
1051 static __be32
1052 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
1053 {
1054 	DECODE_HEAD;
1055 
1056 	READ_BUF(4);
1057 	putfh->pf_fhlen = be32_to_cpup(p++);
1058 	if (putfh->pf_fhlen > NFS4_FHSIZE)
1059 		goto xdr_error;
1060 	READ_BUF(putfh->pf_fhlen);
1061 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
1062 
1063 	DECODE_TAIL;
1064 }
1065 
1066 static __be32
1067 nfsd4_decode_putpubfh(struct nfsd4_compoundargs *argp, void *p)
1068 {
1069 	if (argp->minorversion == 0)
1070 		return nfs_ok;
1071 	return nfserr_notsupp;
1072 }
1073 
1074 static __be32
1075 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
1076 {
1077 	DECODE_HEAD;
1078 
1079 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
1080 	if (status)
1081 		return status;
1082 	READ_BUF(12);
1083 	p = xdr_decode_hyper(p, &read->rd_offset);
1084 	read->rd_length = be32_to_cpup(p++);
1085 
1086 	DECODE_TAIL;
1087 }
1088 
1089 static __be32
1090 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
1091 {
1092 	DECODE_HEAD;
1093 
1094 	READ_BUF(24);
1095 	p = xdr_decode_hyper(p, &readdir->rd_cookie);
1096 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
1097 	readdir->rd_dircount = be32_to_cpup(p++);
1098 	readdir->rd_maxcount = be32_to_cpup(p++);
1099 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
1100 		goto out;
1101 
1102 	DECODE_TAIL;
1103 }
1104 
1105 static __be32
1106 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
1107 {
1108 	DECODE_HEAD;
1109 
1110 	READ_BUF(4);
1111 	remove->rm_namelen = be32_to_cpup(p++);
1112 	READ_BUF(remove->rm_namelen);
1113 	SAVEMEM(remove->rm_name, remove->rm_namelen);
1114 	if ((status = check_filename(remove->rm_name, remove->rm_namelen)))
1115 		return status;
1116 
1117 	DECODE_TAIL;
1118 }
1119 
1120 static __be32
1121 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
1122 {
1123 	DECODE_HEAD;
1124 
1125 	READ_BUF(4);
1126 	rename->rn_snamelen = be32_to_cpup(p++);
1127 	READ_BUF(rename->rn_snamelen);
1128 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1129 	READ_BUF(4);
1130 	rename->rn_tnamelen = be32_to_cpup(p++);
1131 	READ_BUF(rename->rn_tnamelen);
1132 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1133 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1134 		return status;
1135 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1136 		return status;
1137 
1138 	DECODE_TAIL;
1139 }
1140 
1141 static __be32
1142 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1143 {
1144 	DECODE_HEAD;
1145 
1146 	if (argp->minorversion >= 1)
1147 		return nfserr_notsupp;
1148 
1149 	READ_BUF(sizeof(clientid_t));
1150 	COPYMEM(clientid, sizeof(clientid_t));
1151 
1152 	DECODE_TAIL;
1153 }
1154 
1155 static __be32
1156 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1157 		     struct nfsd4_secinfo *secinfo)
1158 {
1159 	DECODE_HEAD;
1160 
1161 	READ_BUF(4);
1162 	secinfo->si_namelen = be32_to_cpup(p++);
1163 	READ_BUF(secinfo->si_namelen);
1164 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1165 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1166 	if (status)
1167 		return status;
1168 	DECODE_TAIL;
1169 }
1170 
1171 static __be32
1172 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1173 		     struct nfsd4_secinfo_no_name *sin)
1174 {
1175 	DECODE_HEAD;
1176 
1177 	READ_BUF(4);
1178 	sin->sin_style = be32_to_cpup(p++);
1179 	DECODE_TAIL;
1180 }
1181 
1182 static __be32
1183 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1184 {
1185 	__be32 status;
1186 
1187 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1188 	if (status)
1189 		return status;
1190 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1191 				  &setattr->sa_acl, &setattr->sa_label, NULL);
1192 }
1193 
1194 static __be32
1195 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1196 {
1197 	DECODE_HEAD;
1198 
1199 	if (argp->minorversion >= 1)
1200 		return nfserr_notsupp;
1201 
1202 	READ_BUF(NFS4_VERIFIER_SIZE);
1203 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1204 
1205 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1206 	if (status)
1207 		return nfserr_bad_xdr;
1208 	READ_BUF(8);
1209 	setclientid->se_callback_prog = be32_to_cpup(p++);
1210 	setclientid->se_callback_netid_len = be32_to_cpup(p++);
1211 	READ_BUF(setclientid->se_callback_netid_len);
1212 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1213 	READ_BUF(4);
1214 	setclientid->se_callback_addr_len = be32_to_cpup(p++);
1215 
1216 	READ_BUF(setclientid->se_callback_addr_len);
1217 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1218 	READ_BUF(4);
1219 	setclientid->se_callback_ident = be32_to_cpup(p++);
1220 
1221 	DECODE_TAIL;
1222 }
1223 
1224 static __be32
1225 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1226 {
1227 	DECODE_HEAD;
1228 
1229 	if (argp->minorversion >= 1)
1230 		return nfserr_notsupp;
1231 
1232 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1233 	COPYMEM(&scd_c->sc_clientid, 8);
1234 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1235 
1236 	DECODE_TAIL;
1237 }
1238 
1239 /* Also used for NVERIFY */
1240 static __be32
1241 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1242 {
1243 	DECODE_HEAD;
1244 
1245 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1246 		goto out;
1247 
1248 	/* For convenience's sake, we compare raw xdr'd attributes in
1249 	 * nfsd4_proc_verify */
1250 
1251 	READ_BUF(4);
1252 	verify->ve_attrlen = be32_to_cpup(p++);
1253 	READ_BUF(verify->ve_attrlen);
1254 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1255 
1256 	DECODE_TAIL;
1257 }
1258 
1259 static __be32
1260 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1261 {
1262 	int avail;
1263 	int len;
1264 	DECODE_HEAD;
1265 
1266 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1267 	if (status)
1268 		return status;
1269 	READ_BUF(16);
1270 	p = xdr_decode_hyper(p, &write->wr_offset);
1271 	write->wr_stable_how = be32_to_cpup(p++);
1272 	if (write->wr_stable_how > NFS_FILE_SYNC)
1273 		goto xdr_error;
1274 	write->wr_buflen = be32_to_cpup(p++);
1275 
1276 	/* Sorry .. no magic macros for this.. *
1277 	 * READ_BUF(write->wr_buflen);
1278 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1279 	 */
1280 	avail = (char*)argp->end - (char*)argp->p;
1281 	if (avail + argp->pagelen < write->wr_buflen) {
1282 		dprintk("NFSD: xdr error (%s:%d)\n",
1283 				__FILE__, __LINE__);
1284 		goto xdr_error;
1285 	}
1286 	write->wr_head.iov_base = p;
1287 	write->wr_head.iov_len = avail;
1288 	write->wr_pagelist = argp->pagelist;
1289 
1290 	len = XDR_QUADLEN(write->wr_buflen) << 2;
1291 	if (len >= avail) {
1292 		int pages;
1293 
1294 		len -= avail;
1295 
1296 		pages = len >> PAGE_SHIFT;
1297 		argp->pagelist += pages;
1298 		argp->pagelen -= pages * PAGE_SIZE;
1299 		len -= pages * PAGE_SIZE;
1300 
1301 		next_decode_page(argp);
1302 	}
1303 	argp->p += XDR_QUADLEN(len);
1304 
1305 	DECODE_TAIL;
1306 }
1307 
1308 static __be32
1309 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1310 {
1311 	DECODE_HEAD;
1312 
1313 	if (argp->minorversion >= 1)
1314 		return nfserr_notsupp;
1315 
1316 	READ_BUF(12);
1317 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1318 	rlockowner->rl_owner.len = be32_to_cpup(p++);
1319 	READ_BUF(rlockowner->rl_owner.len);
1320 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1321 
1322 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1323 		return nfserr_inval;
1324 	DECODE_TAIL;
1325 }
1326 
1327 static __be32
1328 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1329 			 struct nfsd4_exchange_id *exid)
1330 {
1331 	int dummy, tmp;
1332 	DECODE_HEAD;
1333 
1334 	READ_BUF(NFS4_VERIFIER_SIZE);
1335 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1336 
1337 	status = nfsd4_decode_opaque(argp, &exid->clname);
1338 	if (status)
1339 		return nfserr_bad_xdr;
1340 
1341 	READ_BUF(4);
1342 	exid->flags = be32_to_cpup(p++);
1343 
1344 	/* Ignore state_protect4_a */
1345 	READ_BUF(4);
1346 	exid->spa_how = be32_to_cpup(p++);
1347 	switch (exid->spa_how) {
1348 	case SP4_NONE:
1349 		break;
1350 	case SP4_MACH_CRED:
1351 		/* spo_must_enforce */
1352 		status = nfsd4_decode_bitmap(argp,
1353 					exid->spo_must_enforce);
1354 		if (status)
1355 			goto out;
1356 		/* spo_must_allow */
1357 		status = nfsd4_decode_bitmap(argp, exid->spo_must_allow);
1358 		if (status)
1359 			goto out;
1360 		break;
1361 	case SP4_SSV:
1362 		/* ssp_ops */
1363 		READ_BUF(4);
1364 		dummy = be32_to_cpup(p++);
1365 		READ_BUF(dummy * 4);
1366 		p += dummy;
1367 
1368 		READ_BUF(4);
1369 		dummy = be32_to_cpup(p++);
1370 		READ_BUF(dummy * 4);
1371 		p += dummy;
1372 
1373 		/* ssp_hash_algs<> */
1374 		READ_BUF(4);
1375 		tmp = be32_to_cpup(p++);
1376 		while (tmp--) {
1377 			READ_BUF(4);
1378 			dummy = be32_to_cpup(p++);
1379 			READ_BUF(dummy);
1380 			p += XDR_QUADLEN(dummy);
1381 		}
1382 
1383 		/* ssp_encr_algs<> */
1384 		READ_BUF(4);
1385 		tmp = be32_to_cpup(p++);
1386 		while (tmp--) {
1387 			READ_BUF(4);
1388 			dummy = be32_to_cpup(p++);
1389 			READ_BUF(dummy);
1390 			p += XDR_QUADLEN(dummy);
1391 		}
1392 
1393 		/* ignore ssp_window and ssp_num_gss_handles: */
1394 		READ_BUF(8);
1395 		break;
1396 	default:
1397 		goto xdr_error;
1398 	}
1399 
1400 	/* Ignore Implementation ID */
1401 	READ_BUF(4);    /* nfs_impl_id4 array length */
1402 	dummy = be32_to_cpup(p++);
1403 
1404 	if (dummy > 1)
1405 		goto xdr_error;
1406 
1407 	if (dummy == 1) {
1408 		/* nii_domain */
1409 		READ_BUF(4);
1410 		dummy = be32_to_cpup(p++);
1411 		READ_BUF(dummy);
1412 		p += XDR_QUADLEN(dummy);
1413 
1414 		/* nii_name */
1415 		READ_BUF(4);
1416 		dummy = be32_to_cpup(p++);
1417 		READ_BUF(dummy);
1418 		p += XDR_QUADLEN(dummy);
1419 
1420 		/* nii_date */
1421 		READ_BUF(12);
1422 		p += 3;
1423 	}
1424 	DECODE_TAIL;
1425 }
1426 
1427 static __be32
1428 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1429 			    struct nfsd4_create_session *sess)
1430 {
1431 	DECODE_HEAD;
1432 	u32 dummy;
1433 
1434 	READ_BUF(16);
1435 	COPYMEM(&sess->clientid, 8);
1436 	sess->seqid = be32_to_cpup(p++);
1437 	sess->flags = be32_to_cpup(p++);
1438 
1439 	/* Fore channel attrs */
1440 	READ_BUF(28);
1441 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1442 	sess->fore_channel.maxreq_sz = be32_to_cpup(p++);
1443 	sess->fore_channel.maxresp_sz = be32_to_cpup(p++);
1444 	sess->fore_channel.maxresp_cached = be32_to_cpup(p++);
1445 	sess->fore_channel.maxops = be32_to_cpup(p++);
1446 	sess->fore_channel.maxreqs = be32_to_cpup(p++);
1447 	sess->fore_channel.nr_rdma_attrs = be32_to_cpup(p++);
1448 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1449 		READ_BUF(4);
1450 		sess->fore_channel.rdma_attrs = be32_to_cpup(p++);
1451 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1452 		dprintk("Too many fore channel attr bitmaps!\n");
1453 		goto xdr_error;
1454 	}
1455 
1456 	/* Back channel attrs */
1457 	READ_BUF(28);
1458 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1459 	sess->back_channel.maxreq_sz = be32_to_cpup(p++);
1460 	sess->back_channel.maxresp_sz = be32_to_cpup(p++);
1461 	sess->back_channel.maxresp_cached = be32_to_cpup(p++);
1462 	sess->back_channel.maxops = be32_to_cpup(p++);
1463 	sess->back_channel.maxreqs = be32_to_cpup(p++);
1464 	sess->back_channel.nr_rdma_attrs = be32_to_cpup(p++);
1465 	if (sess->back_channel.nr_rdma_attrs == 1) {
1466 		READ_BUF(4);
1467 		sess->back_channel.rdma_attrs = be32_to_cpup(p++);
1468 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1469 		dprintk("Too many back channel attr bitmaps!\n");
1470 		goto xdr_error;
1471 	}
1472 
1473 	READ_BUF(4);
1474 	sess->callback_prog = be32_to_cpup(p++);
1475 	nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1476 	DECODE_TAIL;
1477 }
1478 
1479 static __be32
1480 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1481 			     struct nfsd4_destroy_session *destroy_session)
1482 {
1483 	DECODE_HEAD;
1484 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1485 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1486 
1487 	DECODE_TAIL;
1488 }
1489 
1490 static __be32
1491 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1492 			  struct nfsd4_free_stateid *free_stateid)
1493 {
1494 	DECODE_HEAD;
1495 
1496 	READ_BUF(sizeof(stateid_t));
1497 	free_stateid->fr_stateid.si_generation = be32_to_cpup(p++);
1498 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1499 
1500 	DECODE_TAIL;
1501 }
1502 
1503 static __be32
1504 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1505 		      struct nfsd4_sequence *seq)
1506 {
1507 	DECODE_HEAD;
1508 
1509 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1510 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1511 	seq->seqid = be32_to_cpup(p++);
1512 	seq->slotid = be32_to_cpup(p++);
1513 	seq->maxslots = be32_to_cpup(p++);
1514 	seq->cachethis = be32_to_cpup(p++);
1515 
1516 	DECODE_TAIL;
1517 }
1518 
1519 static __be32
1520 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1521 {
1522 	int i;
1523 	__be32 *p, status;
1524 	struct nfsd4_test_stateid_id *stateid;
1525 
1526 	READ_BUF(4);
1527 	test_stateid->ts_num_ids = ntohl(*p++);
1528 
1529 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1530 
1531 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1532 		stateid = svcxdr_tmpalloc(argp, sizeof(*stateid));
1533 		if (!stateid) {
1534 			status = nfserrno(-ENOMEM);
1535 			goto out;
1536 		}
1537 
1538 		INIT_LIST_HEAD(&stateid->ts_id_list);
1539 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1540 
1541 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1542 		if (status)
1543 			goto out;
1544 	}
1545 
1546 	status = 0;
1547 out:
1548 	return status;
1549 xdr_error:
1550 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1551 	status = nfserr_bad_xdr;
1552 	goto out;
1553 }
1554 
1555 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1556 {
1557 	DECODE_HEAD;
1558 
1559 	READ_BUF(8);
1560 	COPYMEM(&dc->clientid, 8);
1561 
1562 	DECODE_TAIL;
1563 }
1564 
1565 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1566 {
1567 	DECODE_HEAD;
1568 
1569 	READ_BUF(4);
1570 	rc->rca_one_fs = be32_to_cpup(p++);
1571 
1572 	DECODE_TAIL;
1573 }
1574 
1575 #ifdef CONFIG_NFSD_PNFS
1576 static __be32
1577 nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp,
1578 		struct nfsd4_getdeviceinfo *gdev)
1579 {
1580 	DECODE_HEAD;
1581 	u32 num, i;
1582 
1583 	READ_BUF(sizeof(struct nfsd4_deviceid) + 3 * 4);
1584 	COPYMEM(&gdev->gd_devid, sizeof(struct nfsd4_deviceid));
1585 	gdev->gd_layout_type = be32_to_cpup(p++);
1586 	gdev->gd_maxcount = be32_to_cpup(p++);
1587 	num = be32_to_cpup(p++);
1588 	if (num) {
1589 		if (num > 1000)
1590 			goto xdr_error;
1591 		READ_BUF(4 * num);
1592 		gdev->gd_notify_types = be32_to_cpup(p++);
1593 		for (i = 1; i < num; i++) {
1594 			if (be32_to_cpup(p++)) {
1595 				status = nfserr_inval;
1596 				goto out;
1597 			}
1598 		}
1599 	}
1600 	DECODE_TAIL;
1601 }
1602 
1603 static __be32
1604 nfsd4_decode_layoutget(struct nfsd4_compoundargs *argp,
1605 		struct nfsd4_layoutget *lgp)
1606 {
1607 	DECODE_HEAD;
1608 
1609 	READ_BUF(36);
1610 	lgp->lg_signal = be32_to_cpup(p++);
1611 	lgp->lg_layout_type = be32_to_cpup(p++);
1612 	lgp->lg_seg.iomode = be32_to_cpup(p++);
1613 	p = xdr_decode_hyper(p, &lgp->lg_seg.offset);
1614 	p = xdr_decode_hyper(p, &lgp->lg_seg.length);
1615 	p = xdr_decode_hyper(p, &lgp->lg_minlength);
1616 
1617 	status = nfsd4_decode_stateid(argp, &lgp->lg_sid);
1618 	if (status)
1619 		return status;
1620 
1621 	READ_BUF(4);
1622 	lgp->lg_maxcount = be32_to_cpup(p++);
1623 
1624 	DECODE_TAIL;
1625 }
1626 
1627 static __be32
1628 nfsd4_decode_layoutcommit(struct nfsd4_compoundargs *argp,
1629 		struct nfsd4_layoutcommit *lcp)
1630 {
1631 	DECODE_HEAD;
1632 	u32 timechange;
1633 
1634 	READ_BUF(20);
1635 	p = xdr_decode_hyper(p, &lcp->lc_seg.offset);
1636 	p = xdr_decode_hyper(p, &lcp->lc_seg.length);
1637 	lcp->lc_reclaim = be32_to_cpup(p++);
1638 
1639 	status = nfsd4_decode_stateid(argp, &lcp->lc_sid);
1640 	if (status)
1641 		return status;
1642 
1643 	READ_BUF(4);
1644 	lcp->lc_newoffset = be32_to_cpup(p++);
1645 	if (lcp->lc_newoffset) {
1646 		READ_BUF(8);
1647 		p = xdr_decode_hyper(p, &lcp->lc_last_wr);
1648 	} else
1649 		lcp->lc_last_wr = 0;
1650 	READ_BUF(4);
1651 	timechange = be32_to_cpup(p++);
1652 	if (timechange) {
1653 		status = nfsd4_decode_time(argp, &lcp->lc_mtime);
1654 		if (status)
1655 			return status;
1656 	} else {
1657 		lcp->lc_mtime.tv_nsec = UTIME_NOW;
1658 	}
1659 	READ_BUF(8);
1660 	lcp->lc_layout_type = be32_to_cpup(p++);
1661 
1662 	/*
1663 	 * Save the layout update in XDR format and let the layout driver deal
1664 	 * with it later.
1665 	 */
1666 	lcp->lc_up_len = be32_to_cpup(p++);
1667 	if (lcp->lc_up_len > 0) {
1668 		READ_BUF(lcp->lc_up_len);
1669 		READMEM(lcp->lc_up_layout, lcp->lc_up_len);
1670 	}
1671 
1672 	DECODE_TAIL;
1673 }
1674 
1675 static __be32
1676 nfsd4_decode_layoutreturn(struct nfsd4_compoundargs *argp,
1677 		struct nfsd4_layoutreturn *lrp)
1678 {
1679 	DECODE_HEAD;
1680 
1681 	READ_BUF(16);
1682 	lrp->lr_reclaim = be32_to_cpup(p++);
1683 	lrp->lr_layout_type = be32_to_cpup(p++);
1684 	lrp->lr_seg.iomode = be32_to_cpup(p++);
1685 	lrp->lr_return_type = be32_to_cpup(p++);
1686 	if (lrp->lr_return_type == RETURN_FILE) {
1687 		READ_BUF(16);
1688 		p = xdr_decode_hyper(p, &lrp->lr_seg.offset);
1689 		p = xdr_decode_hyper(p, &lrp->lr_seg.length);
1690 
1691 		status = nfsd4_decode_stateid(argp, &lrp->lr_sid);
1692 		if (status)
1693 			return status;
1694 
1695 		READ_BUF(4);
1696 		lrp->lrf_body_len = be32_to_cpup(p++);
1697 		if (lrp->lrf_body_len > 0) {
1698 			READ_BUF(lrp->lrf_body_len);
1699 			READMEM(lrp->lrf_body, lrp->lrf_body_len);
1700 		}
1701 	} else {
1702 		lrp->lr_seg.offset = 0;
1703 		lrp->lr_seg.length = NFS4_MAX_UINT64;
1704 	}
1705 
1706 	DECODE_TAIL;
1707 }
1708 #endif /* CONFIG_NFSD_PNFS */
1709 
1710 static __be32
1711 nfsd4_decode_fallocate(struct nfsd4_compoundargs *argp,
1712 		       struct nfsd4_fallocate *fallocate)
1713 {
1714 	DECODE_HEAD;
1715 
1716 	status = nfsd4_decode_stateid(argp, &fallocate->falloc_stateid);
1717 	if (status)
1718 		return status;
1719 
1720 	READ_BUF(16);
1721 	p = xdr_decode_hyper(p, &fallocate->falloc_offset);
1722 	xdr_decode_hyper(p, &fallocate->falloc_length);
1723 
1724 	DECODE_TAIL;
1725 }
1726 
1727 static __be32
1728 nfsd4_decode_clone(struct nfsd4_compoundargs *argp, struct nfsd4_clone *clone)
1729 {
1730 	DECODE_HEAD;
1731 
1732 	status = nfsd4_decode_stateid(argp, &clone->cl_src_stateid);
1733 	if (status)
1734 		return status;
1735 	status = nfsd4_decode_stateid(argp, &clone->cl_dst_stateid);
1736 	if (status)
1737 		return status;
1738 
1739 	READ_BUF(8 + 8 + 8);
1740 	p = xdr_decode_hyper(p, &clone->cl_src_pos);
1741 	p = xdr_decode_hyper(p, &clone->cl_dst_pos);
1742 	p = xdr_decode_hyper(p, &clone->cl_count);
1743 	DECODE_TAIL;
1744 }
1745 
1746 static __be32
1747 nfsd4_decode_copy(struct nfsd4_compoundargs *argp, struct nfsd4_copy *copy)
1748 {
1749 	DECODE_HEAD;
1750 	unsigned int tmp;
1751 
1752 	status = nfsd4_decode_stateid(argp, &copy->cp_src_stateid);
1753 	if (status)
1754 		return status;
1755 	status = nfsd4_decode_stateid(argp, &copy->cp_dst_stateid);
1756 	if (status)
1757 		return status;
1758 
1759 	READ_BUF(8 + 8 + 8 + 4 + 4 + 4);
1760 	p = xdr_decode_hyper(p, &copy->cp_src_pos);
1761 	p = xdr_decode_hyper(p, &copy->cp_dst_pos);
1762 	p = xdr_decode_hyper(p, &copy->cp_count);
1763 	p++; /* ca_consecutive: we always do consecutive copies */
1764 	copy->cp_synchronous = be32_to_cpup(p++);
1765 	tmp = be32_to_cpup(p); /* Source server list not supported */
1766 
1767 	DECODE_TAIL;
1768 }
1769 
1770 static __be32
1771 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
1772 {
1773 	DECODE_HEAD;
1774 
1775 	status = nfsd4_decode_stateid(argp, &seek->seek_stateid);
1776 	if (status)
1777 		return status;
1778 
1779 	READ_BUF(8 + 4);
1780 	p = xdr_decode_hyper(p, &seek->seek_offset);
1781 	seek->seek_whence = be32_to_cpup(p);
1782 
1783 	DECODE_TAIL;
1784 }
1785 
1786 static __be32
1787 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1788 {
1789 	return nfs_ok;
1790 }
1791 
1792 static __be32
1793 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1794 {
1795 	return nfserr_notsupp;
1796 }
1797 
1798 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1799 
1800 static const nfsd4_dec nfsd4_dec_ops[] = {
1801 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1802 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1803 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1804 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1805 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1806 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1807 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1808 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1809 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1810 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1811 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1812 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1813 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1814 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1815 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1816 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1817 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1818 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1819 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1820 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1821 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_putpubfh,
1822 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1823 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1824 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1825 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1826 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1827 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1828 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1829 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1830 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1831 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1832 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1833 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1834 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1835 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1836 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1837 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1838 
1839 	/* new operations for NFSv4.1 */
1840 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_backchannel_ctl,
1841 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1842 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1843 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1844 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1845 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
1846 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1847 #ifdef CONFIG_NFSD_PNFS
1848 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_getdeviceinfo,
1849 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1850 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_layoutcommit,
1851 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_layoutget,
1852 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_layoutreturn,
1853 #else
1854 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1855 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1856 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1857 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1858 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1859 #endif
1860 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1861 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1862 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1863 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
1864 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1865 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
1866 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1867 
1868 	/* new operations for NFSv4.2 */
1869 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1870 	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_copy,
1871 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
1872 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1873 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1874 	[OP_LAYOUTERROR]	= (nfsd4_dec)nfsd4_decode_notsupp,
1875 	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1876 	[OP_OFFLOAD_CANCEL]	= (nfsd4_dec)nfsd4_decode_notsupp,
1877 	[OP_OFFLOAD_STATUS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1878 	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_notsupp,
1879 	[OP_SEEK]		= (nfsd4_dec)nfsd4_decode_seek,
1880 	[OP_WRITE_SAME]		= (nfsd4_dec)nfsd4_decode_notsupp,
1881 	[OP_CLONE]		= (nfsd4_dec)nfsd4_decode_clone,
1882 };
1883 
1884 static inline bool
1885 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
1886 {
1887 	if (op->opnum < FIRST_NFS4_OP)
1888 		return false;
1889 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
1890 		return false;
1891 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
1892 		return false;
1893 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
1894 		return false;
1895 	return true;
1896 }
1897 
1898 static __be32
1899 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1900 {
1901 	DECODE_HEAD;
1902 	struct nfsd4_op *op;
1903 	bool cachethis = false;
1904 	int auth_slack= argp->rqstp->rq_auth_slack;
1905 	int max_reply = auth_slack + 8; /* opcnt, status */
1906 	int readcount = 0;
1907 	int readbytes = 0;
1908 	int i;
1909 
1910 	READ_BUF(4);
1911 	argp->taglen = be32_to_cpup(p++);
1912 	READ_BUF(argp->taglen);
1913 	SAVEMEM(argp->tag, argp->taglen);
1914 	READ_BUF(8);
1915 	argp->minorversion = be32_to_cpup(p++);
1916 	argp->opcnt = be32_to_cpup(p++);
1917 	max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
1918 
1919 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1920 		goto xdr_error;
1921 	/*
1922 	 * NFS4ERR_RESOURCE is a more helpful error than GARBAGE_ARGS
1923 	 * here, so we return success at the xdr level so that
1924 	 * nfsd4_proc can handle this is an NFS-level error.
1925 	 */
1926 	if (argp->opcnt > NFSD_MAX_OPS_PER_COMPOUND)
1927 		return 0;
1928 
1929 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1930 		argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1931 		if (!argp->ops) {
1932 			argp->ops = argp->iops;
1933 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1934 			goto xdr_error;
1935 		}
1936 	}
1937 
1938 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
1939 		argp->opcnt = 0;
1940 
1941 	for (i = 0; i < argp->opcnt; i++) {
1942 		op = &argp->ops[i];
1943 		op->replay = NULL;
1944 
1945 		READ_BUF(4);
1946 		op->opnum = be32_to_cpup(p++);
1947 
1948 		if (nfsd4_opnum_in_range(argp, op))
1949 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
1950 		else {
1951 			op->opnum = OP_ILLEGAL;
1952 			op->status = nfserr_op_illegal;
1953 		}
1954 		op->opdesc = OPDESC(op);
1955 		/*
1956 		 * We'll try to cache the result in the DRC if any one
1957 		 * op in the compound wants to be cached:
1958 		 */
1959 		cachethis |= nfsd4_cache_this_op(op);
1960 
1961 		if (op->opnum == OP_READ) {
1962 			readcount++;
1963 			readbytes += nfsd4_max_reply(argp->rqstp, op);
1964 		} else
1965 			max_reply += nfsd4_max_reply(argp->rqstp, op);
1966 		/*
1967 		 * OP_LOCK and OP_LOCKT may return a conflicting lock.
1968 		 * (Special case because it will just skip encoding this
1969 		 * if it runs out of xdr buffer space, and it is the only
1970 		 * operation that behaves this way.)
1971 		 */
1972 		if (op->opnum == OP_LOCK || op->opnum == OP_LOCKT)
1973 			max_reply += NFS4_OPAQUE_LIMIT;
1974 
1975 		if (op->status) {
1976 			argp->opcnt = i+1;
1977 			break;
1978 		}
1979 	}
1980 	/* Sessions make the DRC unnecessary: */
1981 	if (argp->minorversion)
1982 		cachethis = false;
1983 	svc_reserve(argp->rqstp, max_reply + readbytes);
1984 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1985 
1986 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
1987 		clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
1988 
1989 	DECODE_TAIL;
1990 }
1991 
1992 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode,
1993 			     struct svc_export *exp)
1994 {
1995 	if (exp->ex_flags & NFSEXP_V4ROOT) {
1996 		*p++ = cpu_to_be32(convert_to_wallclock(exp->cd->flush_time));
1997 		*p++ = 0;
1998 	} else if (IS_I_VERSION(inode)) {
1999 		p = xdr_encode_hyper(p, nfsd4_change_attribute(stat, inode));
2000 	} else {
2001 		*p++ = cpu_to_be32(stat->ctime.tv_sec);
2002 		*p++ = cpu_to_be32(stat->ctime.tv_nsec);
2003 	}
2004 	return p;
2005 }
2006 
2007 /*
2008  * ctime (in NFSv4, time_metadata) is not writeable, and the client
2009  * doesn't really care what resolution could theoretically be stored by
2010  * the filesystem.
2011  *
2012  * The client cares how close together changes can be while still
2013  * guaranteeing ctime changes.  For most filesystems (which have
2014  * timestamps with nanosecond fields) that is limited by the resolution
2015  * of the time returned from current_time() (which I'm assuming to be
2016  * 1/HZ).
2017  */
2018 static __be32 *encode_time_delta(__be32 *p, struct inode *inode)
2019 {
2020 	struct timespec ts;
2021 	u32 ns;
2022 
2023 	ns = max_t(u32, NSEC_PER_SEC/HZ, inode->i_sb->s_time_gran);
2024 	ts = ns_to_timespec(ns);
2025 
2026 	p = xdr_encode_hyper(p, ts.tv_sec);
2027 	*p++ = cpu_to_be32(ts.tv_nsec);
2028 
2029 	return p;
2030 }
2031 
2032 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
2033 {
2034 	*p++ = cpu_to_be32(c->atomic);
2035 	if (c->change_supported) {
2036 		p = xdr_encode_hyper(p, c->before_change);
2037 		p = xdr_encode_hyper(p, c->after_change);
2038 	} else {
2039 		*p++ = cpu_to_be32(c->before_ctime_sec);
2040 		*p++ = cpu_to_be32(c->before_ctime_nsec);
2041 		*p++ = cpu_to_be32(c->after_ctime_sec);
2042 		*p++ = cpu_to_be32(c->after_ctime_nsec);
2043 	}
2044 	return p;
2045 }
2046 
2047 /* Encode as an array of strings the string given with components
2048  * separated @sep, escaped with esc_enter and esc_exit.
2049  */
2050 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
2051 					  char *components, char esc_enter,
2052 					  char esc_exit)
2053 {
2054 	__be32 *p;
2055 	__be32 pathlen;
2056 	int pathlen_offset;
2057 	int strlen, count=0;
2058 	char *str, *end, *next;
2059 
2060 	dprintk("nfsd4_encode_components(%s)\n", components);
2061 
2062 	pathlen_offset = xdr->buf->len;
2063 	p = xdr_reserve_space(xdr, 4);
2064 	if (!p)
2065 		return nfserr_resource;
2066 	p++; /* We will fill this in with @count later */
2067 
2068 	end = str = components;
2069 	while (*end) {
2070 		bool found_esc = false;
2071 
2072 		/* try to parse as esc_start, ..., esc_end, sep */
2073 		if (*str == esc_enter) {
2074 			for (; *end && (*end != esc_exit); end++)
2075 				/* find esc_exit or end of string */;
2076 			next = end + 1;
2077 			if (*end && (!*next || *next == sep)) {
2078 				str++;
2079 				found_esc = true;
2080 			}
2081 		}
2082 
2083 		if (!found_esc)
2084 			for (; *end && (*end != sep); end++)
2085 				/* find sep or end of string */;
2086 
2087 		strlen = end - str;
2088 		if (strlen) {
2089 			p = xdr_reserve_space(xdr, strlen + 4);
2090 			if (!p)
2091 				return nfserr_resource;
2092 			p = xdr_encode_opaque(p, str, strlen);
2093 			count++;
2094 		}
2095 		else
2096 			end++;
2097 		if (found_esc)
2098 			end = next;
2099 
2100 		str = end;
2101 	}
2102 	pathlen = htonl(count);
2103 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
2104 	return 0;
2105 }
2106 
2107 /* Encode as an array of strings the string given with components
2108  * separated @sep.
2109  */
2110 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
2111 				      char *components)
2112 {
2113 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
2114 }
2115 
2116 /*
2117  * encode a location element of a fs_locations structure
2118  */
2119 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
2120 					struct nfsd4_fs_location *location)
2121 {
2122 	__be32 status;
2123 
2124 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
2125 						'[', ']');
2126 	if (status)
2127 		return status;
2128 	status = nfsd4_encode_components(xdr, '/', location->path);
2129 	if (status)
2130 		return status;
2131 	return 0;
2132 }
2133 
2134 /*
2135  * Encode a path in RFC3530 'pathname4' format
2136  */
2137 static __be32 nfsd4_encode_path(struct xdr_stream *xdr,
2138 				const struct path *root,
2139 				const struct path *path)
2140 {
2141 	struct path cur = *path;
2142 	__be32 *p;
2143 	struct dentry **components = NULL;
2144 	unsigned int ncomponents = 0;
2145 	__be32 err = nfserr_jukebox;
2146 
2147 	dprintk("nfsd4_encode_components(");
2148 
2149 	path_get(&cur);
2150 	/* First walk the path up to the nfsd root, and store the
2151 	 * dentries/path components in an array.
2152 	 */
2153 	for (;;) {
2154 		if (path_equal(&cur, root))
2155 			break;
2156 		if (cur.dentry == cur.mnt->mnt_root) {
2157 			if (follow_up(&cur))
2158 				continue;
2159 			goto out_free;
2160 		}
2161 		if ((ncomponents & 15) == 0) {
2162 			struct dentry **new;
2163 			new = krealloc(components,
2164 					sizeof(*new) * (ncomponents + 16),
2165 					GFP_KERNEL);
2166 			if (!new)
2167 				goto out_free;
2168 			components = new;
2169 		}
2170 		components[ncomponents++] = cur.dentry;
2171 		cur.dentry = dget_parent(cur.dentry);
2172 	}
2173 	err = nfserr_resource;
2174 	p = xdr_reserve_space(xdr, 4);
2175 	if (!p)
2176 		goto out_free;
2177 	*p++ = cpu_to_be32(ncomponents);
2178 
2179 	while (ncomponents) {
2180 		struct dentry *dentry = components[ncomponents - 1];
2181 		unsigned int len;
2182 
2183 		spin_lock(&dentry->d_lock);
2184 		len = dentry->d_name.len;
2185 		p = xdr_reserve_space(xdr, len + 4);
2186 		if (!p) {
2187 			spin_unlock(&dentry->d_lock);
2188 			goto out_free;
2189 		}
2190 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
2191 		dprintk("/%pd", dentry);
2192 		spin_unlock(&dentry->d_lock);
2193 		dput(dentry);
2194 		ncomponents--;
2195 	}
2196 
2197 	err = 0;
2198 out_free:
2199 	dprintk(")\n");
2200 	while (ncomponents)
2201 		dput(components[--ncomponents]);
2202 	kfree(components);
2203 	path_put(&cur);
2204 	return err;
2205 }
2206 
2207 static __be32 nfsd4_encode_fsloc_fsroot(struct xdr_stream *xdr,
2208 			struct svc_rqst *rqstp, const struct path *path)
2209 {
2210 	struct svc_export *exp_ps;
2211 	__be32 res;
2212 
2213 	exp_ps = rqst_find_fsidzero_export(rqstp);
2214 	if (IS_ERR(exp_ps))
2215 		return nfserrno(PTR_ERR(exp_ps));
2216 	res = nfsd4_encode_path(xdr, &exp_ps->ex_path, path);
2217 	exp_put(exp_ps);
2218 	return res;
2219 }
2220 
2221 /*
2222  *  encode a fs_locations structure
2223  */
2224 static __be32 nfsd4_encode_fs_locations(struct xdr_stream *xdr,
2225 			struct svc_rqst *rqstp, struct svc_export *exp)
2226 {
2227 	__be32 status;
2228 	int i;
2229 	__be32 *p;
2230 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
2231 
2232 	status = nfsd4_encode_fsloc_fsroot(xdr, rqstp, &exp->ex_path);
2233 	if (status)
2234 		return status;
2235 	p = xdr_reserve_space(xdr, 4);
2236 	if (!p)
2237 		return nfserr_resource;
2238 	*p++ = cpu_to_be32(fslocs->locations_count);
2239 	for (i=0; i<fslocs->locations_count; i++) {
2240 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
2241 		if (status)
2242 			return status;
2243 	}
2244 	return 0;
2245 }
2246 
2247 static u32 nfs4_file_type(umode_t mode)
2248 {
2249 	switch (mode & S_IFMT) {
2250 	case S_IFIFO:	return NF4FIFO;
2251 	case S_IFCHR:	return NF4CHR;
2252 	case S_IFDIR:	return NF4DIR;
2253 	case S_IFBLK:	return NF4BLK;
2254 	case S_IFLNK:	return NF4LNK;
2255 	case S_IFREG:	return NF4REG;
2256 	case S_IFSOCK:	return NF4SOCK;
2257 	default:	return NF4BAD;
2258 	};
2259 }
2260 
2261 static inline __be32
2262 nfsd4_encode_aclname(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2263 		     struct nfs4_ace *ace)
2264 {
2265 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
2266 		return nfs4_acl_write_who(xdr, ace->whotype);
2267 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
2268 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
2269 	else
2270 		return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
2271 }
2272 
2273 static inline __be32
2274 nfsd4_encode_layout_types(struct xdr_stream *xdr, u32 layout_types)
2275 {
2276 	__be32		*p;
2277 	unsigned long	i = hweight_long(layout_types);
2278 
2279 	p = xdr_reserve_space(xdr, 4 + 4 * i);
2280 	if (!p)
2281 		return nfserr_resource;
2282 
2283 	*p++ = cpu_to_be32(i);
2284 
2285 	for (i = LAYOUT_NFSV4_1_FILES; i < LAYOUT_TYPE_MAX; ++i)
2286 		if (layout_types & (1 << i))
2287 			*p++ = cpu_to_be32(i);
2288 
2289 	return 0;
2290 }
2291 
2292 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
2293 			      FATTR4_WORD0_RDATTR_ERROR)
2294 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2295 #define WORD2_ABSENT_FS_ATTRS 0
2296 
2297 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2298 static inline __be32
2299 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2300 			    void *context, int len)
2301 {
2302 	__be32 *p;
2303 
2304 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2305 	if (!p)
2306 		return nfserr_resource;
2307 
2308 	/*
2309 	 * For now we use a 0 here to indicate the null translation; in
2310 	 * the future we may place a call to translation code here.
2311 	 */
2312 	*p++ = cpu_to_be32(0); /* lfs */
2313 	*p++ = cpu_to_be32(0); /* pi */
2314 	p = xdr_encode_opaque(p, context, len);
2315 	return 0;
2316 }
2317 #else
2318 static inline __be32
2319 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2320 			    void *context, int len)
2321 { return 0; }
2322 #endif
2323 
2324 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *bmval2, u32 *rdattr_err)
2325 {
2326 	/* As per referral draft:  */
2327 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2328 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2329 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2330 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2331 			*rdattr_err = NFSERR_MOVED;
2332 		else
2333 			return nfserr_moved;
2334 	}
2335 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2336 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2337 	*bmval2 &= WORD2_ABSENT_FS_ATTRS;
2338 	return 0;
2339 }
2340 
2341 
2342 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2343 {
2344 	struct path path = exp->ex_path;
2345 	int err;
2346 
2347 	path_get(&path);
2348 	while (follow_up(&path)) {
2349 		if (path.dentry != path.mnt->mnt_root)
2350 			break;
2351 	}
2352 	err = vfs_getattr(&path, stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
2353 	path_put(&path);
2354 	return err;
2355 }
2356 
2357 static __be32
2358 nfsd4_encode_bitmap(struct xdr_stream *xdr, u32 bmval0, u32 bmval1, u32 bmval2)
2359 {
2360 	__be32 *p;
2361 
2362 	if (bmval2) {
2363 		p = xdr_reserve_space(xdr, 16);
2364 		if (!p)
2365 			goto out_resource;
2366 		*p++ = cpu_to_be32(3);
2367 		*p++ = cpu_to_be32(bmval0);
2368 		*p++ = cpu_to_be32(bmval1);
2369 		*p++ = cpu_to_be32(bmval2);
2370 	} else if (bmval1) {
2371 		p = xdr_reserve_space(xdr, 12);
2372 		if (!p)
2373 			goto out_resource;
2374 		*p++ = cpu_to_be32(2);
2375 		*p++ = cpu_to_be32(bmval0);
2376 		*p++ = cpu_to_be32(bmval1);
2377 	} else {
2378 		p = xdr_reserve_space(xdr, 8);
2379 		if (!p)
2380 			goto out_resource;
2381 		*p++ = cpu_to_be32(1);
2382 		*p++ = cpu_to_be32(bmval0);
2383 	}
2384 
2385 	return 0;
2386 out_resource:
2387 	return nfserr_resource;
2388 }
2389 
2390 /*
2391  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2392  * ourselves.
2393  */
2394 static __be32
2395 nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
2396 		struct svc_export *exp,
2397 		struct dentry *dentry, u32 *bmval,
2398 		struct svc_rqst *rqstp, int ignore_crossmnt)
2399 {
2400 	u32 bmval0 = bmval[0];
2401 	u32 bmval1 = bmval[1];
2402 	u32 bmval2 = bmval[2];
2403 	struct kstat stat;
2404 	struct svc_fh *tempfh = NULL;
2405 	struct kstatfs statfs;
2406 	__be32 *p;
2407 	int starting_len = xdr->buf->len;
2408 	int attrlen_offset;
2409 	__be32 attrlen;
2410 	u32 dummy;
2411 	u64 dummy64;
2412 	u32 rdattr_err = 0;
2413 	__be32 status;
2414 	int err;
2415 	struct nfs4_acl *acl = NULL;
2416 	void *context = NULL;
2417 	int contextlen;
2418 	bool contextsupport = false;
2419 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2420 	u32 minorversion = resp->cstate.minorversion;
2421 	struct path path = {
2422 		.mnt	= exp->ex_path.mnt,
2423 		.dentry	= dentry,
2424 	};
2425 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2426 
2427 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2428 	BUG_ON(!nfsd_attrs_supported(minorversion, bmval));
2429 
2430 	if (exp->ex_fslocs.migrated) {
2431 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &bmval2, &rdattr_err);
2432 		if (status)
2433 			goto out;
2434 	}
2435 
2436 	err = vfs_getattr(&path, &stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
2437 	if (err)
2438 		goto out_nfserr;
2439 	if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
2440 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
2441 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2442 		       FATTR4_WORD1_SPACE_TOTAL))) {
2443 		err = vfs_statfs(&path, &statfs);
2444 		if (err)
2445 			goto out_nfserr;
2446 	}
2447 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2448 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2449 		status = nfserr_jukebox;
2450 		if (!tempfh)
2451 			goto out;
2452 		fh_init(tempfh, NFS4_FHSIZE);
2453 		status = fh_compose(tempfh, exp, dentry, NULL);
2454 		if (status)
2455 			goto out;
2456 		fhp = tempfh;
2457 	}
2458 	if (bmval0 & FATTR4_WORD0_ACL) {
2459 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2460 		if (err == -EOPNOTSUPP)
2461 			bmval0 &= ~FATTR4_WORD0_ACL;
2462 		else if (err == -EINVAL) {
2463 			status = nfserr_attrnotsupp;
2464 			goto out;
2465 		} else if (err != 0)
2466 			goto out_nfserr;
2467 	}
2468 
2469 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2470 	if ((bmval2 & FATTR4_WORD2_SECURITY_LABEL) ||
2471 	     bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2472 		if (exp->ex_flags & NFSEXP_SECURITY_LABEL)
2473 			err = security_inode_getsecctx(d_inode(dentry),
2474 						&context, &contextlen);
2475 		else
2476 			err = -EOPNOTSUPP;
2477 		contextsupport = (err == 0);
2478 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2479 			if (err == -EOPNOTSUPP)
2480 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2481 			else if (err)
2482 				goto out_nfserr;
2483 		}
2484 	}
2485 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2486 
2487 	status = nfsd4_encode_bitmap(xdr, bmval0, bmval1, bmval2);
2488 	if (status)
2489 		goto out;
2490 
2491 	attrlen_offset = xdr->buf->len;
2492 	p = xdr_reserve_space(xdr, 4);
2493 	if (!p)
2494 		goto out_resource;
2495 	p++;                /* to be backfilled later */
2496 
2497 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2498 		u32 supp[3];
2499 
2500 		memcpy(supp, nfsd_suppattrs[minorversion], sizeof(supp));
2501 
2502 		if (!IS_POSIXACL(dentry->d_inode))
2503 			supp[0] &= ~FATTR4_WORD0_ACL;
2504 		if (!contextsupport)
2505 			supp[2] &= ~FATTR4_WORD2_SECURITY_LABEL;
2506 		if (!supp[2]) {
2507 			p = xdr_reserve_space(xdr, 12);
2508 			if (!p)
2509 				goto out_resource;
2510 			*p++ = cpu_to_be32(2);
2511 			*p++ = cpu_to_be32(supp[0]);
2512 			*p++ = cpu_to_be32(supp[1]);
2513 		} else {
2514 			p = xdr_reserve_space(xdr, 16);
2515 			if (!p)
2516 				goto out_resource;
2517 			*p++ = cpu_to_be32(3);
2518 			*p++ = cpu_to_be32(supp[0]);
2519 			*p++ = cpu_to_be32(supp[1]);
2520 			*p++ = cpu_to_be32(supp[2]);
2521 		}
2522 	}
2523 	if (bmval0 & FATTR4_WORD0_TYPE) {
2524 		p = xdr_reserve_space(xdr, 4);
2525 		if (!p)
2526 			goto out_resource;
2527 		dummy = nfs4_file_type(stat.mode);
2528 		if (dummy == NF4BAD) {
2529 			status = nfserr_serverfault;
2530 			goto out;
2531 		}
2532 		*p++ = cpu_to_be32(dummy);
2533 	}
2534 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2535 		p = xdr_reserve_space(xdr, 4);
2536 		if (!p)
2537 			goto out_resource;
2538 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2539 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT);
2540 		else
2541 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT|
2542 						NFS4_FH_VOL_RENAME);
2543 	}
2544 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2545 		p = xdr_reserve_space(xdr, 8);
2546 		if (!p)
2547 			goto out_resource;
2548 		p = encode_change(p, &stat, d_inode(dentry), exp);
2549 	}
2550 	if (bmval0 & FATTR4_WORD0_SIZE) {
2551 		p = xdr_reserve_space(xdr, 8);
2552 		if (!p)
2553 			goto out_resource;
2554 		p = xdr_encode_hyper(p, stat.size);
2555 	}
2556 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2557 		p = xdr_reserve_space(xdr, 4);
2558 		if (!p)
2559 			goto out_resource;
2560 		*p++ = cpu_to_be32(1);
2561 	}
2562 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2563 		p = xdr_reserve_space(xdr, 4);
2564 		if (!p)
2565 			goto out_resource;
2566 		*p++ = cpu_to_be32(1);
2567 	}
2568 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2569 		p = xdr_reserve_space(xdr, 4);
2570 		if (!p)
2571 			goto out_resource;
2572 		*p++ = cpu_to_be32(0);
2573 	}
2574 	if (bmval0 & FATTR4_WORD0_FSID) {
2575 		p = xdr_reserve_space(xdr, 16);
2576 		if (!p)
2577 			goto out_resource;
2578 		if (exp->ex_fslocs.migrated) {
2579 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
2580 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
2581 		} else switch(fsid_source(fhp)) {
2582 		case FSIDSOURCE_FSID:
2583 			p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
2584 			p = xdr_encode_hyper(p, (u64)0);
2585 			break;
2586 		case FSIDSOURCE_DEV:
2587 			*p++ = cpu_to_be32(0);
2588 			*p++ = cpu_to_be32(MAJOR(stat.dev));
2589 			*p++ = cpu_to_be32(0);
2590 			*p++ = cpu_to_be32(MINOR(stat.dev));
2591 			break;
2592 		case FSIDSOURCE_UUID:
2593 			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
2594 								EX_UUID_LEN);
2595 			break;
2596 		}
2597 	}
2598 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2599 		p = xdr_reserve_space(xdr, 4);
2600 		if (!p)
2601 			goto out_resource;
2602 		*p++ = cpu_to_be32(0);
2603 	}
2604 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2605 		p = xdr_reserve_space(xdr, 4);
2606 		if (!p)
2607 			goto out_resource;
2608 		*p++ = cpu_to_be32(nn->nfsd4_lease);
2609 	}
2610 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2611 		p = xdr_reserve_space(xdr, 4);
2612 		if (!p)
2613 			goto out_resource;
2614 		*p++ = cpu_to_be32(rdattr_err);
2615 	}
2616 	if (bmval0 & FATTR4_WORD0_ACL) {
2617 		struct nfs4_ace *ace;
2618 
2619 		if (acl == NULL) {
2620 			p = xdr_reserve_space(xdr, 4);
2621 			if (!p)
2622 				goto out_resource;
2623 
2624 			*p++ = cpu_to_be32(0);
2625 			goto out_acl;
2626 		}
2627 		p = xdr_reserve_space(xdr, 4);
2628 		if (!p)
2629 			goto out_resource;
2630 		*p++ = cpu_to_be32(acl->naces);
2631 
2632 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2633 			p = xdr_reserve_space(xdr, 4*3);
2634 			if (!p)
2635 				goto out_resource;
2636 			*p++ = cpu_to_be32(ace->type);
2637 			*p++ = cpu_to_be32(ace->flag);
2638 			*p++ = cpu_to_be32(ace->access_mask &
2639 							NFS4_ACE_MASK_ALL);
2640 			status = nfsd4_encode_aclname(xdr, rqstp, ace);
2641 			if (status)
2642 				goto out;
2643 		}
2644 	}
2645 out_acl:
2646 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2647 		p = xdr_reserve_space(xdr, 4);
2648 		if (!p)
2649 			goto out_resource;
2650 		*p++ = cpu_to_be32(IS_POSIXACL(dentry->d_inode) ?
2651 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2652 	}
2653 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2654 		p = xdr_reserve_space(xdr, 4);
2655 		if (!p)
2656 			goto out_resource;
2657 		*p++ = cpu_to_be32(1);
2658 	}
2659 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2660 		p = xdr_reserve_space(xdr, 4);
2661 		if (!p)
2662 			goto out_resource;
2663 		*p++ = cpu_to_be32(0);
2664 	}
2665 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2666 		p = xdr_reserve_space(xdr, 4);
2667 		if (!p)
2668 			goto out_resource;
2669 		*p++ = cpu_to_be32(1);
2670 	}
2671 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2672 		p = xdr_reserve_space(xdr, 4);
2673 		if (!p)
2674 			goto out_resource;
2675 		*p++ = cpu_to_be32(1);
2676 	}
2677 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2678 		p = xdr_reserve_space(xdr, fhp->fh_handle.fh_size + 4);
2679 		if (!p)
2680 			goto out_resource;
2681 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base,
2682 					fhp->fh_handle.fh_size);
2683 	}
2684 	if (bmval0 & FATTR4_WORD0_FILEID) {
2685 		p = xdr_reserve_space(xdr, 8);
2686 		if (!p)
2687 			goto out_resource;
2688 		p = xdr_encode_hyper(p, stat.ino);
2689 	}
2690 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2691 		p = xdr_reserve_space(xdr, 8);
2692 		if (!p)
2693 			goto out_resource;
2694 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2695 	}
2696 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2697 		p = xdr_reserve_space(xdr, 8);
2698 		if (!p)
2699 			goto out_resource;
2700 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2701 	}
2702 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2703 		p = xdr_reserve_space(xdr, 8);
2704 		if (!p)
2705 			goto out_resource;
2706 		p = xdr_encode_hyper(p, (u64) statfs.f_files);
2707 	}
2708 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2709 		status = nfsd4_encode_fs_locations(xdr, rqstp, exp);
2710 		if (status)
2711 			goto out;
2712 	}
2713 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2714 		p = xdr_reserve_space(xdr, 4);
2715 		if (!p)
2716 			goto out_resource;
2717 		*p++ = cpu_to_be32(1);
2718 	}
2719 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2720 		p = xdr_reserve_space(xdr, 8);
2721 		if (!p)
2722 			goto out_resource;
2723 		p = xdr_encode_hyper(p, exp->ex_path.mnt->mnt_sb->s_maxbytes);
2724 	}
2725 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2726 		p = xdr_reserve_space(xdr, 4);
2727 		if (!p)
2728 			goto out_resource;
2729 		*p++ = cpu_to_be32(255);
2730 	}
2731 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2732 		p = xdr_reserve_space(xdr, 4);
2733 		if (!p)
2734 			goto out_resource;
2735 		*p++ = cpu_to_be32(statfs.f_namelen);
2736 	}
2737 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2738 		p = xdr_reserve_space(xdr, 8);
2739 		if (!p)
2740 			goto out_resource;
2741 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2742 	}
2743 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2744 		p = xdr_reserve_space(xdr, 8);
2745 		if (!p)
2746 			goto out_resource;
2747 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2748 	}
2749 	if (bmval1 & FATTR4_WORD1_MODE) {
2750 		p = xdr_reserve_space(xdr, 4);
2751 		if (!p)
2752 			goto out_resource;
2753 		*p++ = cpu_to_be32(stat.mode & S_IALLUGO);
2754 	}
2755 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2756 		p = xdr_reserve_space(xdr, 4);
2757 		if (!p)
2758 			goto out_resource;
2759 		*p++ = cpu_to_be32(1);
2760 	}
2761 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2762 		p = xdr_reserve_space(xdr, 4);
2763 		if (!p)
2764 			goto out_resource;
2765 		*p++ = cpu_to_be32(stat.nlink);
2766 	}
2767 	if (bmval1 & FATTR4_WORD1_OWNER) {
2768 		status = nfsd4_encode_user(xdr, rqstp, stat.uid);
2769 		if (status)
2770 			goto out;
2771 	}
2772 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2773 		status = nfsd4_encode_group(xdr, rqstp, stat.gid);
2774 		if (status)
2775 			goto out;
2776 	}
2777 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2778 		p = xdr_reserve_space(xdr, 8);
2779 		if (!p)
2780 			goto out_resource;
2781 		*p++ = cpu_to_be32((u32) MAJOR(stat.rdev));
2782 		*p++ = cpu_to_be32((u32) MINOR(stat.rdev));
2783 	}
2784 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2785 		p = xdr_reserve_space(xdr, 8);
2786 		if (!p)
2787 			goto out_resource;
2788 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2789 		p = xdr_encode_hyper(p, dummy64);
2790 	}
2791 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2792 		p = xdr_reserve_space(xdr, 8);
2793 		if (!p)
2794 			goto out_resource;
2795 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2796 		p = xdr_encode_hyper(p, dummy64);
2797 	}
2798 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2799 		p = xdr_reserve_space(xdr, 8);
2800 		if (!p)
2801 			goto out_resource;
2802 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2803 		p = xdr_encode_hyper(p, dummy64);
2804 	}
2805 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2806 		p = xdr_reserve_space(xdr, 8);
2807 		if (!p)
2808 			goto out_resource;
2809 		dummy64 = (u64)stat.blocks << 9;
2810 		p = xdr_encode_hyper(p, dummy64);
2811 	}
2812 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2813 		p = xdr_reserve_space(xdr, 12);
2814 		if (!p)
2815 			goto out_resource;
2816 		p = xdr_encode_hyper(p, (s64)stat.atime.tv_sec);
2817 		*p++ = cpu_to_be32(stat.atime.tv_nsec);
2818 	}
2819 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2820 		p = xdr_reserve_space(xdr, 12);
2821 		if (!p)
2822 			goto out_resource;
2823 		p = encode_time_delta(p, d_inode(dentry));
2824 	}
2825 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2826 		p = xdr_reserve_space(xdr, 12);
2827 		if (!p)
2828 			goto out_resource;
2829 		p = xdr_encode_hyper(p, (s64)stat.ctime.tv_sec);
2830 		*p++ = cpu_to_be32(stat.ctime.tv_nsec);
2831 	}
2832 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2833 		p = xdr_reserve_space(xdr, 12);
2834 		if (!p)
2835 			goto out_resource;
2836 		p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
2837 		*p++ = cpu_to_be32(stat.mtime.tv_nsec);
2838 	}
2839 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2840 		struct kstat parent_stat;
2841 		u64 ino = stat.ino;
2842 
2843 		p = xdr_reserve_space(xdr, 8);
2844 		if (!p)
2845                 	goto out_resource;
2846 		/*
2847 		 * Get parent's attributes if not ignoring crossmount
2848 		 * and this is the root of a cross-mounted filesystem.
2849 		 */
2850 		if (ignore_crossmnt == 0 &&
2851 		    dentry == exp->ex_path.mnt->mnt_root) {
2852 			err = get_parent_attributes(exp, &parent_stat);
2853 			if (err)
2854 				goto out_nfserr;
2855 			ino = parent_stat.ino;
2856 		}
2857 		p = xdr_encode_hyper(p, ino);
2858 	}
2859 #ifdef CONFIG_NFSD_PNFS
2860 	if (bmval1 & FATTR4_WORD1_FS_LAYOUT_TYPES) {
2861 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
2862 		if (status)
2863 			goto out;
2864 	}
2865 
2866 	if (bmval2 & FATTR4_WORD2_LAYOUT_TYPES) {
2867 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
2868 		if (status)
2869 			goto out;
2870 	}
2871 
2872 	if (bmval2 & FATTR4_WORD2_LAYOUT_BLKSIZE) {
2873 		p = xdr_reserve_space(xdr, 4);
2874 		if (!p)
2875 			goto out_resource;
2876 		*p++ = cpu_to_be32(stat.blksize);
2877 	}
2878 #endif /* CONFIG_NFSD_PNFS */
2879 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2880 		u32 supp[3];
2881 
2882 		memcpy(supp, nfsd_suppattrs[minorversion], sizeof(supp));
2883 		supp[0] &= NFSD_SUPPATTR_EXCLCREAT_WORD0;
2884 		supp[1] &= NFSD_SUPPATTR_EXCLCREAT_WORD1;
2885 		supp[2] &= NFSD_SUPPATTR_EXCLCREAT_WORD2;
2886 
2887 		status = nfsd4_encode_bitmap(xdr, supp[0], supp[1], supp[2]);
2888 		if (status)
2889 			goto out;
2890 	}
2891 
2892 	if (bmval2 & FATTR4_WORD2_CHANGE_ATTR_TYPE) {
2893 		p = xdr_reserve_space(xdr, 4);
2894 		if (!p)
2895 			goto out_resource;
2896 		if (IS_I_VERSION(d_inode(dentry)))
2897 			*p++ = cpu_to_be32(NFS4_CHANGE_TYPE_IS_MONOTONIC_INCR);
2898 		else
2899 			*p++ = cpu_to_be32(NFS4_CHANGE_TYPE_IS_TIME_METADATA);
2900 	}
2901 
2902 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2903 		status = nfsd4_encode_security_label(xdr, rqstp, context,
2904 								contextlen);
2905 		if (status)
2906 			goto out;
2907 	}
2908 
2909 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
2910 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
2911 	status = nfs_ok;
2912 
2913 out:
2914 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2915 	if (context)
2916 		security_release_secctx(context, contextlen);
2917 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2918 	kfree(acl);
2919 	if (tempfh) {
2920 		fh_put(tempfh);
2921 		kfree(tempfh);
2922 	}
2923 	if (status)
2924 		xdr_truncate_encode(xdr, starting_len);
2925 	return status;
2926 out_nfserr:
2927 	status = nfserrno(err);
2928 	goto out;
2929 out_resource:
2930 	status = nfserr_resource;
2931 	goto out;
2932 }
2933 
2934 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
2935 				struct xdr_buf *buf, __be32 *p, int bytes)
2936 {
2937 	xdr->scratch.iov_len = 0;
2938 	memset(buf, 0, sizeof(struct xdr_buf));
2939 	buf->head[0].iov_base = p;
2940 	buf->head[0].iov_len = 0;
2941 	buf->len = 0;
2942 	xdr->buf = buf;
2943 	xdr->iov = buf->head;
2944 	xdr->p = p;
2945 	xdr->end = (void *)p + bytes;
2946 	buf->buflen = bytes;
2947 }
2948 
2949 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
2950 			struct svc_fh *fhp, struct svc_export *exp,
2951 			struct dentry *dentry, u32 *bmval,
2952 			struct svc_rqst *rqstp, int ignore_crossmnt)
2953 {
2954 	struct xdr_buf dummy;
2955 	struct xdr_stream xdr;
2956 	__be32 ret;
2957 
2958 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
2959 	ret = nfsd4_encode_fattr(&xdr, fhp, exp, dentry, bmval, rqstp,
2960 							ignore_crossmnt);
2961 	*p = xdr.p;
2962 	return ret;
2963 }
2964 
2965 static inline int attributes_need_mount(u32 *bmval)
2966 {
2967 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2968 		return 1;
2969 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2970 		return 1;
2971 	return 0;
2972 }
2973 
2974 static __be32
2975 nfsd4_encode_dirent_fattr(struct xdr_stream *xdr, struct nfsd4_readdir *cd,
2976 			const char *name, int namlen)
2977 {
2978 	struct svc_export *exp = cd->rd_fhp->fh_export;
2979 	struct dentry *dentry;
2980 	__be32 nfserr;
2981 	int ignore_crossmnt = 0;
2982 
2983 	dentry = lookup_one_len_unlocked(name, cd->rd_fhp->fh_dentry, namlen);
2984 	if (IS_ERR(dentry))
2985 		return nfserrno(PTR_ERR(dentry));
2986 	if (d_really_is_negative(dentry)) {
2987 		/*
2988 		 * we're not holding the i_mutex here, so there's
2989 		 * a window where this directory entry could have gone
2990 		 * away.
2991 		 */
2992 		dput(dentry);
2993 		return nfserr_noent;
2994 	}
2995 
2996 	exp_get(exp);
2997 	/*
2998 	 * In the case of a mountpoint, the client may be asking for
2999 	 * attributes that are only properties of the underlying filesystem
3000 	 * as opposed to the cross-mounted file system. In such a case,
3001 	 * we will not follow the cross mount and will fill the attribtutes
3002 	 * directly from the mountpoint dentry.
3003 	 */
3004 	if (nfsd_mountpoint(dentry, exp)) {
3005 		int err;
3006 
3007 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
3008 				&& !attributes_need_mount(cd->rd_bmval)) {
3009 			ignore_crossmnt = 1;
3010 			goto out_encode;
3011 		}
3012 		/*
3013 		 * Why the heck aren't we just using nfsd_lookup??
3014 		 * Different "."/".." handling?  Something else?
3015 		 * At least, add a comment here to explain....
3016 		 */
3017 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
3018 		if (err) {
3019 			nfserr = nfserrno(err);
3020 			goto out_put;
3021 		}
3022 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
3023 		if (nfserr)
3024 			goto out_put;
3025 
3026 	}
3027 out_encode:
3028 	nfserr = nfsd4_encode_fattr(xdr, NULL, exp, dentry, cd->rd_bmval,
3029 					cd->rd_rqstp, ignore_crossmnt);
3030 out_put:
3031 	dput(dentry);
3032 	exp_put(exp);
3033 	return nfserr;
3034 }
3035 
3036 static __be32 *
3037 nfsd4_encode_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
3038 {
3039 	__be32 *p;
3040 
3041 	p = xdr_reserve_space(xdr, 20);
3042 	if (!p)
3043 		return NULL;
3044 	*p++ = htonl(2);
3045 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
3046 	*p++ = htonl(0);			 /* bmval1 */
3047 
3048 	*p++ = htonl(4);     /* attribute length */
3049 	*p++ = nfserr;       /* no htonl */
3050 	return p;
3051 }
3052 
3053 static int
3054 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
3055 		    loff_t offset, u64 ino, unsigned int d_type)
3056 {
3057 	struct readdir_cd *ccd = ccdv;
3058 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
3059 	struct xdr_stream *xdr = cd->xdr;
3060 	int start_offset = xdr->buf->len;
3061 	int cookie_offset;
3062 	u32 name_and_cookie;
3063 	int entry_bytes;
3064 	__be32 nfserr = nfserr_toosmall;
3065 	__be64 wire_offset;
3066 	__be32 *p;
3067 
3068 	/* In nfsv4, "." and ".." never make it onto the wire.. */
3069 	if (name && isdotent(name, namlen)) {
3070 		cd->common.err = nfs_ok;
3071 		return 0;
3072 	}
3073 
3074 	if (cd->cookie_offset) {
3075 		wire_offset = cpu_to_be64(offset);
3076 		write_bytes_to_xdr_buf(xdr->buf, cd->cookie_offset,
3077 							&wire_offset, 8);
3078 	}
3079 
3080 	p = xdr_reserve_space(xdr, 4);
3081 	if (!p)
3082 		goto fail;
3083 	*p++ = xdr_one;                             /* mark entry present */
3084 	cookie_offset = xdr->buf->len;
3085 	p = xdr_reserve_space(xdr, 3*4 + namlen);
3086 	if (!p)
3087 		goto fail;
3088 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
3089 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
3090 
3091 	nfserr = nfsd4_encode_dirent_fattr(xdr, cd, name, namlen);
3092 	switch (nfserr) {
3093 	case nfs_ok:
3094 		break;
3095 	case nfserr_resource:
3096 		nfserr = nfserr_toosmall;
3097 		goto fail;
3098 	case nfserr_noent:
3099 		xdr_truncate_encode(xdr, start_offset);
3100 		goto skip_entry;
3101 	default:
3102 		/*
3103 		 * If the client requested the RDATTR_ERROR attribute,
3104 		 * we stuff the error code into this attribute
3105 		 * and continue.  If this attribute was not requested,
3106 		 * then in accordance with the spec, we fail the
3107 		 * entire READDIR operation(!)
3108 		 */
3109 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
3110 			goto fail;
3111 		p = nfsd4_encode_rdattr_error(xdr, nfserr);
3112 		if (p == NULL) {
3113 			nfserr = nfserr_toosmall;
3114 			goto fail;
3115 		}
3116 	}
3117 	nfserr = nfserr_toosmall;
3118 	entry_bytes = xdr->buf->len - start_offset;
3119 	if (entry_bytes > cd->rd_maxcount)
3120 		goto fail;
3121 	cd->rd_maxcount -= entry_bytes;
3122 	/*
3123 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so
3124 	 * let's always let through the first entry, at least:
3125 	 */
3126 	if (!cd->rd_dircount)
3127 		goto fail;
3128 	name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8;
3129 	if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
3130 		goto fail;
3131 	cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
3132 
3133 	cd->cookie_offset = cookie_offset;
3134 skip_entry:
3135 	cd->common.err = nfs_ok;
3136 	return 0;
3137 fail:
3138 	xdr_truncate_encode(xdr, start_offset);
3139 	cd->common.err = nfserr;
3140 	return -EINVAL;
3141 }
3142 
3143 static __be32
3144 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
3145 {
3146 	__be32 *p;
3147 
3148 	p = xdr_reserve_space(xdr, sizeof(stateid_t));
3149 	if (!p)
3150 		return nfserr_resource;
3151 	*p++ = cpu_to_be32(sid->si_generation);
3152 	p = xdr_encode_opaque_fixed(p, &sid->si_opaque,
3153 					sizeof(stateid_opaque_t));
3154 	return 0;
3155 }
3156 
3157 static __be32
3158 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
3159 {
3160 	struct xdr_stream *xdr = &resp->xdr;
3161 	__be32 *p;
3162 
3163 	p = xdr_reserve_space(xdr, 8);
3164 	if (!p)
3165 		return nfserr_resource;
3166 	*p++ = cpu_to_be32(access->ac_supported);
3167 	*p++ = cpu_to_be32(access->ac_resp_access);
3168 	return 0;
3169 }
3170 
3171 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
3172 {
3173 	struct xdr_stream *xdr = &resp->xdr;
3174 	__be32 *p;
3175 
3176 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 8);
3177 	if (!p)
3178 		return nfserr_resource;
3179 	p = xdr_encode_opaque_fixed(p, bcts->sessionid.data,
3180 					NFS4_MAX_SESSIONID_LEN);
3181 	*p++ = cpu_to_be32(bcts->dir);
3182 	/* Upshifting from TCP to RDMA is not supported */
3183 	*p++ = cpu_to_be32(0);
3184 	return 0;
3185 }
3186 
3187 static __be32
3188 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
3189 {
3190 	struct xdr_stream *xdr = &resp->xdr;
3191 
3192 	return nfsd4_encode_stateid(xdr, &close->cl_stateid);
3193 }
3194 
3195 
3196 static __be32
3197 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
3198 {
3199 	struct xdr_stream *xdr = &resp->xdr;
3200 	__be32 *p;
3201 
3202 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3203 	if (!p)
3204 		return nfserr_resource;
3205 	p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
3206 						NFS4_VERIFIER_SIZE);
3207 	return 0;
3208 }
3209 
3210 static __be32
3211 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
3212 {
3213 	struct xdr_stream *xdr = &resp->xdr;
3214 	__be32 *p;
3215 
3216 	p = xdr_reserve_space(xdr, 20);
3217 	if (!p)
3218 		return nfserr_resource;
3219 	encode_cinfo(p, &create->cr_cinfo);
3220 	nfserr = nfsd4_encode_bitmap(xdr, create->cr_bmval[0],
3221 			create->cr_bmval[1], create->cr_bmval[2]);
3222 	return 0;
3223 }
3224 
3225 static __be32
3226 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
3227 {
3228 	struct svc_fh *fhp = getattr->ga_fhp;
3229 	struct xdr_stream *xdr = &resp->xdr;
3230 
3231 	return nfsd4_encode_fattr(xdr, fhp, fhp->fh_export, fhp->fh_dentry,
3232 				    getattr->ga_bmval, resp->rqstp, 0);
3233 }
3234 
3235 static __be32
3236 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
3237 {
3238 	struct xdr_stream *xdr = &resp->xdr;
3239 	struct svc_fh *fhp = *fhpp;
3240 	unsigned int len;
3241 	__be32 *p;
3242 
3243 	len = fhp->fh_handle.fh_size;
3244 	p = xdr_reserve_space(xdr, len + 4);
3245 	if (!p)
3246 		return nfserr_resource;
3247 	p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base, len);
3248 	return 0;
3249 }
3250 
3251 /*
3252 * Including all fields other than the name, a LOCK4denied structure requires
3253 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
3254 */
3255 static __be32
3256 nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld)
3257 {
3258 	struct xdr_netobj *conf = &ld->ld_owner;
3259 	__be32 *p;
3260 
3261 again:
3262 	p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len));
3263 	if (!p) {
3264 		/*
3265 		 * Don't fail to return the result just because we can't
3266 		 * return the conflicting open:
3267 		 */
3268 		if (conf->len) {
3269 			kfree(conf->data);
3270 			conf->len = 0;
3271 			conf->data = NULL;
3272 			goto again;
3273 		}
3274 		return nfserr_resource;
3275 	}
3276 	p = xdr_encode_hyper(p, ld->ld_start);
3277 	p = xdr_encode_hyper(p, ld->ld_length);
3278 	*p++ = cpu_to_be32(ld->ld_type);
3279 	if (conf->len) {
3280 		p = xdr_encode_opaque_fixed(p, &ld->ld_clientid, 8);
3281 		p = xdr_encode_opaque(p, conf->data, conf->len);
3282 		kfree(conf->data);
3283 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
3284 		p = xdr_encode_hyper(p, (u64)0); /* clientid */
3285 		*p++ = cpu_to_be32(0); /* length of owner name */
3286 	}
3287 	return nfserr_denied;
3288 }
3289 
3290 static __be32
3291 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
3292 {
3293 	struct xdr_stream *xdr = &resp->xdr;
3294 
3295 	if (!nfserr)
3296 		nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid);
3297 	else if (nfserr == nfserr_denied)
3298 		nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied);
3299 
3300 	return nfserr;
3301 }
3302 
3303 static __be32
3304 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
3305 {
3306 	struct xdr_stream *xdr = &resp->xdr;
3307 
3308 	if (nfserr == nfserr_denied)
3309 		nfsd4_encode_lock_denied(xdr, &lockt->lt_denied);
3310 	return nfserr;
3311 }
3312 
3313 static __be32
3314 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
3315 {
3316 	struct xdr_stream *xdr = &resp->xdr;
3317 
3318 	return nfsd4_encode_stateid(xdr, &locku->lu_stateid);
3319 }
3320 
3321 
3322 static __be32
3323 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
3324 {
3325 	struct xdr_stream *xdr = &resp->xdr;
3326 	__be32 *p;
3327 
3328 	p = xdr_reserve_space(xdr, 20);
3329 	if (!p)
3330 		return nfserr_resource;
3331 	p = encode_cinfo(p, &link->li_cinfo);
3332 	return 0;
3333 }
3334 
3335 
3336 static __be32
3337 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
3338 {
3339 	struct xdr_stream *xdr = &resp->xdr;
3340 	__be32 *p;
3341 
3342 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
3343 	if (nfserr)
3344 		return nfserr;
3345 	p = xdr_reserve_space(xdr, 24);
3346 	if (!p)
3347 		return nfserr_resource;
3348 	p = encode_cinfo(p, &open->op_cinfo);
3349 	*p++ = cpu_to_be32(open->op_rflags);
3350 
3351 	nfserr = nfsd4_encode_bitmap(xdr, open->op_bmval[0], open->op_bmval[1],
3352 					open->op_bmval[2]);
3353 	if (nfserr)
3354 		return nfserr;
3355 
3356 	p = xdr_reserve_space(xdr, 4);
3357 	if (!p)
3358 		return nfserr_resource;
3359 
3360 	*p++ = cpu_to_be32(open->op_delegate_type);
3361 	switch (open->op_delegate_type) {
3362 	case NFS4_OPEN_DELEGATE_NONE:
3363 		break;
3364 	case NFS4_OPEN_DELEGATE_READ:
3365 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3366 		if (nfserr)
3367 			return nfserr;
3368 		p = xdr_reserve_space(xdr, 20);
3369 		if (!p)
3370 			return nfserr_resource;
3371 		*p++ = cpu_to_be32(open->op_recall);
3372 
3373 		/*
3374 		 * TODO: ACE's in delegations
3375 		 */
3376 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3377 		*p++ = cpu_to_be32(0);
3378 		*p++ = cpu_to_be32(0);
3379 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3380 		break;
3381 	case NFS4_OPEN_DELEGATE_WRITE:
3382 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3383 		if (nfserr)
3384 			return nfserr;
3385 		p = xdr_reserve_space(xdr, 32);
3386 		if (!p)
3387 			return nfserr_resource;
3388 		*p++ = cpu_to_be32(0);
3389 
3390 		/*
3391 		 * TODO: space_limit's in delegations
3392 		 */
3393 		*p++ = cpu_to_be32(NFS4_LIMIT_SIZE);
3394 		*p++ = cpu_to_be32(~(u32)0);
3395 		*p++ = cpu_to_be32(~(u32)0);
3396 
3397 		/*
3398 		 * TODO: ACE's in delegations
3399 		 */
3400 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3401 		*p++ = cpu_to_be32(0);
3402 		*p++ = cpu_to_be32(0);
3403 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3404 		break;
3405 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
3406 		switch (open->op_why_no_deleg) {
3407 		case WND4_CONTENTION:
3408 		case WND4_RESOURCE:
3409 			p = xdr_reserve_space(xdr, 8);
3410 			if (!p)
3411 				return nfserr_resource;
3412 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3413 			/* deleg signaling not supported yet: */
3414 			*p++ = cpu_to_be32(0);
3415 			break;
3416 		default:
3417 			p = xdr_reserve_space(xdr, 4);
3418 			if (!p)
3419 				return nfserr_resource;
3420 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3421 		}
3422 		break;
3423 	default:
3424 		BUG();
3425 	}
3426 	/* XXX save filehandle here */
3427 	return 0;
3428 }
3429 
3430 static __be32
3431 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
3432 {
3433 	struct xdr_stream *xdr = &resp->xdr;
3434 
3435 	return nfsd4_encode_stateid(xdr, &oc->oc_resp_stateid);
3436 }
3437 
3438 static __be32
3439 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
3440 {
3441 	struct xdr_stream *xdr = &resp->xdr;
3442 
3443 	return nfsd4_encode_stateid(xdr, &od->od_stateid);
3444 }
3445 
3446 static __be32 nfsd4_encode_splice_read(
3447 				struct nfsd4_compoundres *resp,
3448 				struct nfsd4_read *read,
3449 				struct file *file, unsigned long maxcount)
3450 {
3451 	struct xdr_stream *xdr = &resp->xdr;
3452 	struct xdr_buf *buf = xdr->buf;
3453 	u32 eof;
3454 	long len;
3455 	int space_left;
3456 	__be32 nfserr;
3457 	__be32 *p = xdr->p - 2;
3458 
3459 	/* Make sure there will be room for padding if needed */
3460 	if (xdr->end - xdr->p < 1)
3461 		return nfserr_resource;
3462 
3463 	len = maxcount;
3464 	nfserr = nfsd_splice_read(read->rd_rqstp, read->rd_fhp,
3465 				  file, read->rd_offset, &maxcount);
3466 	read->rd_length = maxcount;
3467 	if (nfserr) {
3468 		/*
3469 		 * nfsd_splice_actor may have already messed with the
3470 		 * page length; reset it so as not to confuse
3471 		 * xdr_truncate_encode:
3472 		 */
3473 		buf->page_len = 0;
3474 		return nfserr;
3475 	}
3476 
3477 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3478 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3479 
3480 	*(p++) = htonl(eof);
3481 	*(p++) = htonl(maxcount);
3482 
3483 	buf->page_len = maxcount;
3484 	buf->len += maxcount;
3485 	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
3486 							/ PAGE_SIZE;
3487 
3488 	/* Use rest of head for padding and remaining ops: */
3489 	buf->tail[0].iov_base = xdr->p;
3490 	buf->tail[0].iov_len = 0;
3491 	xdr->iov = buf->tail;
3492 	if (maxcount&3) {
3493 		int pad = 4 - (maxcount&3);
3494 
3495 		*(xdr->p++) = 0;
3496 
3497 		buf->tail[0].iov_base += maxcount&3;
3498 		buf->tail[0].iov_len = pad;
3499 		buf->len += pad;
3500 	}
3501 
3502 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
3503 				buf->buflen - buf->len);
3504 	buf->buflen = buf->len + space_left;
3505 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
3506 
3507 	return 0;
3508 }
3509 
3510 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
3511 				 struct nfsd4_read *read,
3512 				 struct file *file, unsigned long maxcount)
3513 {
3514 	struct xdr_stream *xdr = &resp->xdr;
3515 	u32 eof;
3516 	int v;
3517 	int starting_len = xdr->buf->len - 8;
3518 	long len;
3519 	int thislen;
3520 	__be32 nfserr;
3521 	__be32 tmp;
3522 	__be32 *p;
3523 	u32 zzz = 0;
3524 	int pad;
3525 
3526 	len = maxcount;
3527 	v = 0;
3528 
3529 	thislen = min_t(long, len, ((void *)xdr->end - (void *)xdr->p));
3530 	p = xdr_reserve_space(xdr, (thislen+3)&~3);
3531 	WARN_ON_ONCE(!p);
3532 	resp->rqstp->rq_vec[v].iov_base = p;
3533 	resp->rqstp->rq_vec[v].iov_len = thislen;
3534 	v++;
3535 	len -= thislen;
3536 
3537 	while (len) {
3538 		thislen = min_t(long, len, PAGE_SIZE);
3539 		p = xdr_reserve_space(xdr, (thislen+3)&~3);
3540 		WARN_ON_ONCE(!p);
3541 		resp->rqstp->rq_vec[v].iov_base = p;
3542 		resp->rqstp->rq_vec[v].iov_len = thislen;
3543 		v++;
3544 		len -= thislen;
3545 	}
3546 	read->rd_vlen = v;
3547 
3548 	len = maxcount;
3549 	nfserr = nfsd_readv(resp->rqstp, read->rd_fhp, file, read->rd_offset,
3550 			    resp->rqstp->rq_vec, read->rd_vlen, &maxcount);
3551 	read->rd_length = maxcount;
3552 	if (nfserr)
3553 		return nfserr;
3554 	xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3));
3555 
3556 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3557 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3558 
3559 	tmp = htonl(eof);
3560 	write_bytes_to_xdr_buf(xdr->buf, starting_len    , &tmp, 4);
3561 	tmp = htonl(maxcount);
3562 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
3563 
3564 	pad = (maxcount&3) ? 4 - (maxcount&3) : 0;
3565 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 8 + maxcount,
3566 								&zzz, pad);
3567 	return 0;
3568 
3569 }
3570 
3571 static __be32
3572 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
3573 		  struct nfsd4_read *read)
3574 {
3575 	unsigned long maxcount;
3576 	struct xdr_stream *xdr = &resp->xdr;
3577 	struct file *file = read->rd_filp;
3578 	int starting_len = xdr->buf->len;
3579 	struct raparms *ra = NULL;
3580 	__be32 *p;
3581 
3582 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
3583 	if (!p) {
3584 		WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
3585 		return nfserr_resource;
3586 	}
3587 	if (resp->xdr.buf->page_len &&
3588 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
3589 		WARN_ON_ONCE(1);
3590 		return nfserr_resource;
3591 	}
3592 	xdr_commit_encode(xdr);
3593 
3594 	maxcount = svc_max_payload(resp->rqstp);
3595 	maxcount = min_t(unsigned long, maxcount,
3596 			 (xdr->buf->buflen - xdr->buf->len));
3597 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
3598 
3599 	if (read->rd_tmp_file)
3600 		ra = nfsd_init_raparms(file);
3601 
3602 	if (file->f_op->splice_read &&
3603 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
3604 		nfserr = nfsd4_encode_splice_read(resp, read, file, maxcount);
3605 	else
3606 		nfserr = nfsd4_encode_readv(resp, read, file, maxcount);
3607 
3608 	if (ra)
3609 		nfsd_put_raparams(file, ra);
3610 
3611 	if (nfserr)
3612 		xdr_truncate_encode(xdr, starting_len);
3613 
3614 	return nfserr;
3615 }
3616 
3617 static __be32
3618 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3619 {
3620 	int maxcount;
3621 	__be32 wire_count;
3622 	int zero = 0;
3623 	struct xdr_stream *xdr = &resp->xdr;
3624 	int length_offset = xdr->buf->len;
3625 	__be32 *p;
3626 
3627 	p = xdr_reserve_space(xdr, 4);
3628 	if (!p)
3629 		return nfserr_resource;
3630 	maxcount = PAGE_SIZE;
3631 
3632 	p = xdr_reserve_space(xdr, maxcount);
3633 	if (!p)
3634 		return nfserr_resource;
3635 	/*
3636 	 * XXX: By default, vfs_readlink() will truncate symlinks if they
3637 	 * would overflow the buffer.  Is this kosher in NFSv4?  If not, one
3638 	 * easy fix is: if vfs_readlink() precisely fills the buffer, assume
3639 	 * that truncation occurred, and return NFS4ERR_RESOURCE.
3640 	 */
3641 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
3642 						(char *)p, &maxcount);
3643 	if (nfserr == nfserr_isdir)
3644 		nfserr = nfserr_inval;
3645 	if (nfserr) {
3646 		xdr_truncate_encode(xdr, length_offset);
3647 		return nfserr;
3648 	}
3649 
3650 	wire_count = htonl(maxcount);
3651 	write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
3652 	xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
3653 	if (maxcount & 3)
3654 		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
3655 						&zero, 4 - (maxcount&3));
3656 	return 0;
3657 }
3658 
3659 static __be32
3660 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3661 {
3662 	int maxcount;
3663 	int bytes_left;
3664 	loff_t offset;
3665 	__be64 wire_offset;
3666 	struct xdr_stream *xdr = &resp->xdr;
3667 	int starting_len = xdr->buf->len;
3668 	__be32 *p;
3669 
3670 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3671 	if (!p)
3672 		return nfserr_resource;
3673 
3674 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3675 	*p++ = cpu_to_be32(0);
3676 	*p++ = cpu_to_be32(0);
3677 	resp->xdr.buf->head[0].iov_len = ((char *)resp->xdr.p)
3678 				- (char *)resp->xdr.buf->head[0].iov_base;
3679 
3680 	/*
3681 	 * Number of bytes left for directory entries allowing for the
3682 	 * final 8 bytes of the readdir and a following failed op:
3683 	 */
3684 	bytes_left = xdr->buf->buflen - xdr->buf->len
3685 			- COMPOUND_ERR_SLACK_SPACE - 8;
3686 	if (bytes_left < 0) {
3687 		nfserr = nfserr_resource;
3688 		goto err_no_verf;
3689 	}
3690 	maxcount = svc_max_payload(resp->rqstp);
3691 	maxcount = min_t(u32, readdir->rd_maxcount, maxcount);
3692 	/*
3693 	 * Note the rfc defines rd_maxcount as the size of the
3694 	 * READDIR4resok structure, which includes the verifier above
3695 	 * and the 8 bytes encoded at the end of this function:
3696 	 */
3697 	if (maxcount < 16) {
3698 		nfserr = nfserr_toosmall;
3699 		goto err_no_verf;
3700 	}
3701 	maxcount = min_t(int, maxcount-16, bytes_left);
3702 
3703 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
3704 	if (!readdir->rd_dircount)
3705 		readdir->rd_dircount = svc_max_payload(resp->rqstp);
3706 
3707 	readdir->xdr = xdr;
3708 	readdir->rd_maxcount = maxcount;
3709 	readdir->common.err = 0;
3710 	readdir->cookie_offset = 0;
3711 
3712 	offset = readdir->rd_cookie;
3713 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3714 			      &offset,
3715 			      &readdir->common, nfsd4_encode_dirent);
3716 	if (nfserr == nfs_ok &&
3717 	    readdir->common.err == nfserr_toosmall &&
3718 	    xdr->buf->len == starting_len + 8) {
3719 		/* nothing encoded; which limit did we hit?: */
3720 		if (maxcount - 16 < bytes_left)
3721 			/* It was the fault of rd_maxcount: */
3722 			nfserr = nfserr_toosmall;
3723 		else
3724 			/* We ran out of buffer space: */
3725 			nfserr = nfserr_resource;
3726 	}
3727 	if (nfserr)
3728 		goto err_no_verf;
3729 
3730 	if (readdir->cookie_offset) {
3731 		wire_offset = cpu_to_be64(offset);
3732 		write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset,
3733 							&wire_offset, 8);
3734 	}
3735 
3736 	p = xdr_reserve_space(xdr, 8);
3737 	if (!p) {
3738 		WARN_ON_ONCE(1);
3739 		goto err_no_verf;
3740 	}
3741 	*p++ = 0;	/* no more entries */
3742 	*p++ = htonl(readdir->common.err == nfserr_eof);
3743 
3744 	return 0;
3745 err_no_verf:
3746 	xdr_truncate_encode(xdr, starting_len);
3747 	return nfserr;
3748 }
3749 
3750 static __be32
3751 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3752 {
3753 	struct xdr_stream *xdr = &resp->xdr;
3754 	__be32 *p;
3755 
3756 	p = xdr_reserve_space(xdr, 20);
3757 	if (!p)
3758 		return nfserr_resource;
3759 	p = encode_cinfo(p, &remove->rm_cinfo);
3760 	return 0;
3761 }
3762 
3763 static __be32
3764 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3765 {
3766 	struct xdr_stream *xdr = &resp->xdr;
3767 	__be32 *p;
3768 
3769 	p = xdr_reserve_space(xdr, 40);
3770 	if (!p)
3771 		return nfserr_resource;
3772 	p = encode_cinfo(p, &rename->rn_sinfo);
3773 	p = encode_cinfo(p, &rename->rn_tinfo);
3774 	return 0;
3775 }
3776 
3777 static __be32
3778 nfsd4_do_encode_secinfo(struct xdr_stream *xdr, struct svc_export *exp)
3779 {
3780 	u32 i, nflavs, supported;
3781 	struct exp_flavor_info *flavs;
3782 	struct exp_flavor_info def_flavs[2];
3783 	__be32 *p, *flavorsp;
3784 	static bool report = true;
3785 
3786 	if (exp->ex_nflavors) {
3787 		flavs = exp->ex_flavors;
3788 		nflavs = exp->ex_nflavors;
3789 	} else { /* Handling of some defaults in absence of real secinfo: */
3790 		flavs = def_flavs;
3791 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3792 			nflavs = 2;
3793 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3794 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3795 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3796 			nflavs = 1;
3797 			flavs[0].pseudoflavor
3798 					= svcauth_gss_flavor(exp->ex_client);
3799 		} else {
3800 			nflavs = 1;
3801 			flavs[0].pseudoflavor
3802 					= exp->ex_client->flavour->flavour;
3803 		}
3804 	}
3805 
3806 	supported = 0;
3807 	p = xdr_reserve_space(xdr, 4);
3808 	if (!p)
3809 		return nfserr_resource;
3810 	flavorsp = p++;		/* to be backfilled later */
3811 
3812 	for (i = 0; i < nflavs; i++) {
3813 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
3814 		struct rpcsec_gss_info info;
3815 
3816 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
3817 			supported++;
3818 			p = xdr_reserve_space(xdr, 4 + 4 +
3819 					      XDR_LEN(info.oid.len) + 4 + 4);
3820 			if (!p)
3821 				return nfserr_resource;
3822 			*p++ = cpu_to_be32(RPC_AUTH_GSS);
3823 			p = xdr_encode_opaque(p,  info.oid.data, info.oid.len);
3824 			*p++ = cpu_to_be32(info.qop);
3825 			*p++ = cpu_to_be32(info.service);
3826 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
3827 			supported++;
3828 			p = xdr_reserve_space(xdr, 4);
3829 			if (!p)
3830 				return nfserr_resource;
3831 			*p++ = cpu_to_be32(pf);
3832 		} else {
3833 			if (report)
3834 				pr_warn("NFS: SECINFO: security flavor %u "
3835 					"is not supported\n", pf);
3836 		}
3837 	}
3838 
3839 	if (nflavs != supported)
3840 		report = false;
3841 	*flavorsp = htonl(supported);
3842 	return 0;
3843 }
3844 
3845 static __be32
3846 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3847 		     struct nfsd4_secinfo *secinfo)
3848 {
3849 	struct xdr_stream *xdr = &resp->xdr;
3850 
3851 	return nfsd4_do_encode_secinfo(xdr, secinfo->si_exp);
3852 }
3853 
3854 static __be32
3855 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3856 		     struct nfsd4_secinfo_no_name *secinfo)
3857 {
3858 	struct xdr_stream *xdr = &resp->xdr;
3859 
3860 	return nfsd4_do_encode_secinfo(xdr, secinfo->sin_exp);
3861 }
3862 
3863 /*
3864  * The SETATTR encode routine is special -- it always encodes a bitmap,
3865  * regardless of the error status.
3866  */
3867 static __be32
3868 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3869 {
3870 	struct xdr_stream *xdr = &resp->xdr;
3871 	__be32 *p;
3872 
3873 	p = xdr_reserve_space(xdr, 16);
3874 	if (!p)
3875 		return nfserr_resource;
3876 	if (nfserr) {
3877 		*p++ = cpu_to_be32(3);
3878 		*p++ = cpu_to_be32(0);
3879 		*p++ = cpu_to_be32(0);
3880 		*p++ = cpu_to_be32(0);
3881 	}
3882 	else {
3883 		*p++ = cpu_to_be32(3);
3884 		*p++ = cpu_to_be32(setattr->sa_bmval[0]);
3885 		*p++ = cpu_to_be32(setattr->sa_bmval[1]);
3886 		*p++ = cpu_to_be32(setattr->sa_bmval[2]);
3887 	}
3888 	return nfserr;
3889 }
3890 
3891 static __be32
3892 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3893 {
3894 	struct xdr_stream *xdr = &resp->xdr;
3895 	__be32 *p;
3896 
3897 	if (!nfserr) {
3898 		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
3899 		if (!p)
3900 			return nfserr_resource;
3901 		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
3902 		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
3903 						NFS4_VERIFIER_SIZE);
3904 	}
3905 	else if (nfserr == nfserr_clid_inuse) {
3906 		p = xdr_reserve_space(xdr, 8);
3907 		if (!p)
3908 			return nfserr_resource;
3909 		*p++ = cpu_to_be32(0);
3910 		*p++ = cpu_to_be32(0);
3911 	}
3912 	return nfserr;
3913 }
3914 
3915 static __be32
3916 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3917 {
3918 	struct xdr_stream *xdr = &resp->xdr;
3919 	__be32 *p;
3920 
3921 	p = xdr_reserve_space(xdr, 16);
3922 	if (!p)
3923 		return nfserr_resource;
3924 	*p++ = cpu_to_be32(write->wr_bytes_written);
3925 	*p++ = cpu_to_be32(write->wr_how_written);
3926 	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
3927 						NFS4_VERIFIER_SIZE);
3928 	return 0;
3929 }
3930 
3931 static __be32
3932 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
3933 			 struct nfsd4_exchange_id *exid)
3934 {
3935 	struct xdr_stream *xdr = &resp->xdr;
3936 	__be32 *p;
3937 	char *major_id;
3938 	char *server_scope;
3939 	int major_id_sz;
3940 	int server_scope_sz;
3941 	uint64_t minor_id = 0;
3942 
3943 	major_id = utsname()->nodename;
3944 	major_id_sz = strlen(major_id);
3945 	server_scope = utsname()->nodename;
3946 	server_scope_sz = strlen(server_scope);
3947 
3948 	p = xdr_reserve_space(xdr,
3949 		8 /* eir_clientid */ +
3950 		4 /* eir_sequenceid */ +
3951 		4 /* eir_flags */ +
3952 		4 /* spr_how */);
3953 	if (!p)
3954 		return nfserr_resource;
3955 
3956 	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
3957 	*p++ = cpu_to_be32(exid->seqid);
3958 	*p++ = cpu_to_be32(exid->flags);
3959 
3960 	*p++ = cpu_to_be32(exid->spa_how);
3961 
3962 	switch (exid->spa_how) {
3963 	case SP4_NONE:
3964 		break;
3965 	case SP4_MACH_CRED:
3966 		/* spo_must_enforce bitmap: */
3967 		nfserr = nfsd4_encode_bitmap(xdr,
3968 					exid->spo_must_enforce[0],
3969 					exid->spo_must_enforce[1],
3970 					exid->spo_must_enforce[2]);
3971 		if (nfserr)
3972 			return nfserr;
3973 		/* spo_must_allow bitmap: */
3974 		nfserr = nfsd4_encode_bitmap(xdr,
3975 					exid->spo_must_allow[0],
3976 					exid->spo_must_allow[1],
3977 					exid->spo_must_allow[2]);
3978 		if (nfserr)
3979 			return nfserr;
3980 		break;
3981 	default:
3982 		WARN_ON_ONCE(1);
3983 	}
3984 
3985 	p = xdr_reserve_space(xdr,
3986 		8 /* so_minor_id */ +
3987 		4 /* so_major_id.len */ +
3988 		(XDR_QUADLEN(major_id_sz) * 4) +
3989 		4 /* eir_server_scope.len */ +
3990 		(XDR_QUADLEN(server_scope_sz) * 4) +
3991 		4 /* eir_server_impl_id.count (0) */);
3992 	if (!p)
3993 		return nfserr_resource;
3994 
3995 	/* The server_owner struct */
3996 	p = xdr_encode_hyper(p, minor_id);      /* Minor id */
3997 	/* major id */
3998 	p = xdr_encode_opaque(p, major_id, major_id_sz);
3999 
4000 	/* Server scope */
4001 	p = xdr_encode_opaque(p, server_scope, server_scope_sz);
4002 
4003 	/* Implementation id */
4004 	*p++ = cpu_to_be32(0);	/* zero length nfs_impl_id4 array */
4005 	return 0;
4006 }
4007 
4008 static __be32
4009 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
4010 			    struct nfsd4_create_session *sess)
4011 {
4012 	struct xdr_stream *xdr = &resp->xdr;
4013 	__be32 *p;
4014 
4015 	p = xdr_reserve_space(xdr, 24);
4016 	if (!p)
4017 		return nfserr_resource;
4018 	p = xdr_encode_opaque_fixed(p, sess->sessionid.data,
4019 					NFS4_MAX_SESSIONID_LEN);
4020 	*p++ = cpu_to_be32(sess->seqid);
4021 	*p++ = cpu_to_be32(sess->flags);
4022 
4023 	p = xdr_reserve_space(xdr, 28);
4024 	if (!p)
4025 		return nfserr_resource;
4026 	*p++ = cpu_to_be32(0); /* headerpadsz */
4027 	*p++ = cpu_to_be32(sess->fore_channel.maxreq_sz);
4028 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_sz);
4029 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_cached);
4030 	*p++ = cpu_to_be32(sess->fore_channel.maxops);
4031 	*p++ = cpu_to_be32(sess->fore_channel.maxreqs);
4032 	*p++ = cpu_to_be32(sess->fore_channel.nr_rdma_attrs);
4033 
4034 	if (sess->fore_channel.nr_rdma_attrs) {
4035 		p = xdr_reserve_space(xdr, 4);
4036 		if (!p)
4037 			return nfserr_resource;
4038 		*p++ = cpu_to_be32(sess->fore_channel.rdma_attrs);
4039 	}
4040 
4041 	p = xdr_reserve_space(xdr, 28);
4042 	if (!p)
4043 		return nfserr_resource;
4044 	*p++ = cpu_to_be32(0); /* headerpadsz */
4045 	*p++ = cpu_to_be32(sess->back_channel.maxreq_sz);
4046 	*p++ = cpu_to_be32(sess->back_channel.maxresp_sz);
4047 	*p++ = cpu_to_be32(sess->back_channel.maxresp_cached);
4048 	*p++ = cpu_to_be32(sess->back_channel.maxops);
4049 	*p++ = cpu_to_be32(sess->back_channel.maxreqs);
4050 	*p++ = cpu_to_be32(sess->back_channel.nr_rdma_attrs);
4051 
4052 	if (sess->back_channel.nr_rdma_attrs) {
4053 		p = xdr_reserve_space(xdr, 4);
4054 		if (!p)
4055 			return nfserr_resource;
4056 		*p++ = cpu_to_be32(sess->back_channel.rdma_attrs);
4057 	}
4058 	return 0;
4059 }
4060 
4061 static __be32
4062 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
4063 		      struct nfsd4_sequence *seq)
4064 {
4065 	struct xdr_stream *xdr = &resp->xdr;
4066 	__be32 *p;
4067 
4068 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 20);
4069 	if (!p)
4070 		return nfserr_resource;
4071 	p = xdr_encode_opaque_fixed(p, seq->sessionid.data,
4072 					NFS4_MAX_SESSIONID_LEN);
4073 	*p++ = cpu_to_be32(seq->seqid);
4074 	*p++ = cpu_to_be32(seq->slotid);
4075 	/* Note slotid's are numbered from zero: */
4076 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_highest_slotid */
4077 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_target_highest_slotid */
4078 	*p++ = cpu_to_be32(seq->status_flags);
4079 
4080 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
4081 	return 0;
4082 }
4083 
4084 static __be32
4085 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
4086 			  struct nfsd4_test_stateid *test_stateid)
4087 {
4088 	struct xdr_stream *xdr = &resp->xdr;
4089 	struct nfsd4_test_stateid_id *stateid, *next;
4090 	__be32 *p;
4091 
4092 	p = xdr_reserve_space(xdr, 4 + (4 * test_stateid->ts_num_ids));
4093 	if (!p)
4094 		return nfserr_resource;
4095 	*p++ = htonl(test_stateid->ts_num_ids);
4096 
4097 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
4098 		*p++ = stateid->ts_id_status;
4099 	}
4100 
4101 	return 0;
4102 }
4103 
4104 #ifdef CONFIG_NFSD_PNFS
4105 static __be32
4106 nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
4107 		struct nfsd4_getdeviceinfo *gdev)
4108 {
4109 	struct xdr_stream *xdr = &resp->xdr;
4110 	const struct nfsd4_layout_ops *ops;
4111 	u32 starting_len = xdr->buf->len, needed_len;
4112 	__be32 *p;
4113 
4114 	p = xdr_reserve_space(xdr, 4);
4115 	if (!p)
4116 		return nfserr_resource;
4117 
4118 	*p++ = cpu_to_be32(gdev->gd_layout_type);
4119 
4120 	/* If maxcount is 0 then just update notifications */
4121 	if (gdev->gd_maxcount != 0) {
4122 		ops = nfsd4_layout_ops[gdev->gd_layout_type];
4123 		nfserr = ops->encode_getdeviceinfo(xdr, gdev);
4124 		if (nfserr) {
4125 			/*
4126 			 * We don't bother to burden the layout drivers with
4127 			 * enforcing gd_maxcount, just tell the client to
4128 			 * come back with a bigger buffer if it's not enough.
4129 			 */
4130 			if (xdr->buf->len + 4 > gdev->gd_maxcount)
4131 				goto toosmall;
4132 			return nfserr;
4133 		}
4134 	}
4135 
4136 	if (gdev->gd_notify_types) {
4137 		p = xdr_reserve_space(xdr, 4 + 4);
4138 		if (!p)
4139 			return nfserr_resource;
4140 		*p++ = cpu_to_be32(1);			/* bitmap length */
4141 		*p++ = cpu_to_be32(gdev->gd_notify_types);
4142 	} else {
4143 		p = xdr_reserve_space(xdr, 4);
4144 		if (!p)
4145 			return nfserr_resource;
4146 		*p++ = 0;
4147 	}
4148 
4149 	return 0;
4150 toosmall:
4151 	dprintk("%s: maxcount too small\n", __func__);
4152 	needed_len = xdr->buf->len + 4 /* notifications */;
4153 	xdr_truncate_encode(xdr, starting_len);
4154 	p = xdr_reserve_space(xdr, 4);
4155 	if (!p)
4156 		return nfserr_resource;
4157 	*p++ = cpu_to_be32(needed_len);
4158 	return nfserr_toosmall;
4159 }
4160 
4161 static __be32
4162 nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr,
4163 		struct nfsd4_layoutget *lgp)
4164 {
4165 	struct xdr_stream *xdr = &resp->xdr;
4166 	const struct nfsd4_layout_ops *ops;
4167 	__be32 *p;
4168 
4169 	p = xdr_reserve_space(xdr, 36 + sizeof(stateid_opaque_t));
4170 	if (!p)
4171 		return nfserr_resource;
4172 
4173 	*p++ = cpu_to_be32(1);	/* we always set return-on-close */
4174 	*p++ = cpu_to_be32(lgp->lg_sid.si_generation);
4175 	p = xdr_encode_opaque_fixed(p, &lgp->lg_sid.si_opaque,
4176 				    sizeof(stateid_opaque_t));
4177 
4178 	*p++ = cpu_to_be32(1);	/* we always return a single layout */
4179 	p = xdr_encode_hyper(p, lgp->lg_seg.offset);
4180 	p = xdr_encode_hyper(p, lgp->lg_seg.length);
4181 	*p++ = cpu_to_be32(lgp->lg_seg.iomode);
4182 	*p++ = cpu_to_be32(lgp->lg_layout_type);
4183 
4184 	ops = nfsd4_layout_ops[lgp->lg_layout_type];
4185 	return ops->encode_layoutget(xdr, lgp);
4186 }
4187 
4188 static __be32
4189 nfsd4_encode_layoutcommit(struct nfsd4_compoundres *resp, __be32 nfserr,
4190 			  struct nfsd4_layoutcommit *lcp)
4191 {
4192 	struct xdr_stream *xdr = &resp->xdr;
4193 	__be32 *p;
4194 
4195 	p = xdr_reserve_space(xdr, 4);
4196 	if (!p)
4197 		return nfserr_resource;
4198 	*p++ = cpu_to_be32(lcp->lc_size_chg);
4199 	if (lcp->lc_size_chg) {
4200 		p = xdr_reserve_space(xdr, 8);
4201 		if (!p)
4202 			return nfserr_resource;
4203 		p = xdr_encode_hyper(p, lcp->lc_newsize);
4204 	}
4205 
4206 	return 0;
4207 }
4208 
4209 static __be32
4210 nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
4211 		struct nfsd4_layoutreturn *lrp)
4212 {
4213 	struct xdr_stream *xdr = &resp->xdr;
4214 	__be32 *p;
4215 
4216 	p = xdr_reserve_space(xdr, 4);
4217 	if (!p)
4218 		return nfserr_resource;
4219 	*p++ = cpu_to_be32(lrp->lrs_present);
4220 	if (lrp->lrs_present)
4221 		return nfsd4_encode_stateid(xdr, &lrp->lr_sid);
4222 	return 0;
4223 }
4224 #endif /* CONFIG_NFSD_PNFS */
4225 
4226 static __be32
4227 nfsd42_encode_write_res(struct nfsd4_compoundres *resp, struct nfsd42_write_res *write)
4228 {
4229 	__be32 *p;
4230 
4231 	p = xdr_reserve_space(&resp->xdr, 4 + 8 + 4 + NFS4_VERIFIER_SIZE);
4232 	if (!p)
4233 		return nfserr_resource;
4234 
4235 	*p++ = cpu_to_be32(0);
4236 	p = xdr_encode_hyper(p, write->wr_bytes_written);
4237 	*p++ = cpu_to_be32(write->wr_stable_how);
4238 	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
4239 				    NFS4_VERIFIER_SIZE);
4240 	return nfs_ok;
4241 }
4242 
4243 static __be32
4244 nfsd4_encode_copy(struct nfsd4_compoundres *resp, __be32 nfserr,
4245 		  struct nfsd4_copy *copy)
4246 {
4247 	__be32 *p;
4248 
4249 	nfserr = nfsd42_encode_write_res(resp, &copy->cp_res);
4250 	if (nfserr)
4251 		return nfserr;
4252 
4253 	p = xdr_reserve_space(&resp->xdr, 4 + 4);
4254 	*p++ = xdr_one; /* cr_consecutive */
4255 	*p++ = cpu_to_be32(copy->cp_synchronous);
4256 	return 0;
4257 }
4258 
4259 static __be32
4260 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
4261 		  struct nfsd4_seek *seek)
4262 {
4263 	__be32 *p;
4264 
4265 	p = xdr_reserve_space(&resp->xdr, 4 + 8);
4266 	*p++ = cpu_to_be32(seek->seek_eof);
4267 	p = xdr_encode_hyper(p, seek->seek_pos);
4268 
4269 	return 0;
4270 }
4271 
4272 static __be32
4273 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
4274 {
4275 	return nfserr;
4276 }
4277 
4278 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
4279 
4280 /*
4281  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
4282  * since we don't need to filter out obsolete ops as this is
4283  * done in the decoding phase.
4284  */
4285 static const nfsd4_enc nfsd4_enc_ops[] = {
4286 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
4287 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
4288 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
4289 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
4290 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
4291 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4292 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
4293 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
4294 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
4295 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
4296 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
4297 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
4298 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
4299 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
4300 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4301 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
4302 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
4303 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
4304 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
4305 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4306 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
4307 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4308 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
4309 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
4310 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
4311 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
4312 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
4313 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
4314 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
4315 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
4316 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
4317 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
4318 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
4319 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
4320 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4321 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
4322 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
4323 
4324 	/* NFSv4.1 operations */
4325 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
4326 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
4327 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
4328 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
4329 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
4330 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
4331 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4332 #ifdef CONFIG_NFSD_PNFS
4333 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_getdeviceinfo,
4334 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4335 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_layoutcommit,
4336 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_layoutget,
4337 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_layoutreturn,
4338 #else
4339 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
4340 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4341 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
4342 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
4343 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4344 #endif
4345 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
4346 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
4347 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
4348 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
4349 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4350 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
4351 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
4352 
4353 	/* NFSv4.2 operations */
4354 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4355 	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_copy,
4356 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
4357 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4358 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
4359 	[OP_LAYOUTERROR]	= (nfsd4_enc)nfsd4_encode_noop,
4360 	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,
4361 	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,
4362 	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_noop,
4363 	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_noop,
4364 	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,
4365 	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,
4366 	[OP_CLONE]		= (nfsd4_enc)nfsd4_encode_noop,
4367 };
4368 
4369 /*
4370  * Calculate whether we still have space to encode repsize bytes.
4371  * There are two considerations:
4372  *     - For NFS versions >=4.1, the size of the reply must stay within
4373  *       session limits
4374  *     - For all NFS versions, we must stay within limited preallocated
4375  *       buffer space.
4376  *
4377  * This is called before the operation is processed, so can only provide
4378  * an upper estimate.  For some nonidempotent operations (such as
4379  * getattr), it's not necessarily a problem if that estimate is wrong,
4380  * as we can fail it after processing without significant side effects.
4381  */
4382 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
4383 {
4384 	struct xdr_buf *buf = &resp->rqstp->rq_res;
4385 	struct nfsd4_slot *slot = resp->cstate.slot;
4386 
4387 	if (buf->len + respsize <= buf->buflen)
4388 		return nfs_ok;
4389 	if (!nfsd4_has_session(&resp->cstate))
4390 		return nfserr_resource;
4391 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
4392 		WARN_ON_ONCE(1);
4393 		return nfserr_rep_too_big_to_cache;
4394 	}
4395 	return nfserr_rep_too_big;
4396 }
4397 
4398 void
4399 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
4400 {
4401 	struct xdr_stream *xdr = &resp->xdr;
4402 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
4403 	struct svc_rqst *rqstp = resp->rqstp;
4404 	const struct nfsd4_operation *opdesc = op->opdesc;
4405 	int post_err_offset;
4406 	nfsd4_enc encoder;
4407 	__be32 *p;
4408 
4409 	p = xdr_reserve_space(xdr, 8);
4410 	if (!p) {
4411 		WARN_ON_ONCE(1);
4412 		return;
4413 	}
4414 	*p++ = cpu_to_be32(op->opnum);
4415 	post_err_offset = xdr->buf->len;
4416 
4417 	if (op->opnum == OP_ILLEGAL)
4418 		goto status;
4419 	if (op->status && opdesc &&
4420 			!(opdesc->op_flags & OP_NONTRIVIAL_ERROR_ENCODE))
4421 		goto status;
4422 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
4423 	       !nfsd4_enc_ops[op->opnum]);
4424 	encoder = nfsd4_enc_ops[op->opnum];
4425 	op->status = encoder(resp, op->status, &op->u);
4426 	if (opdesc && opdesc->op_release)
4427 		opdesc->op_release(&op->u);
4428 	xdr_commit_encode(xdr);
4429 
4430 	/* nfsd4_check_resp_size guarantees enough room for error status */
4431 	if (!op->status) {
4432 		int space_needed = 0;
4433 		if (!nfsd4_last_compound_op(rqstp))
4434 			space_needed = COMPOUND_ERR_SLACK_SPACE;
4435 		op->status = nfsd4_check_resp_size(resp, space_needed);
4436 	}
4437 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
4438 		struct nfsd4_slot *slot = resp->cstate.slot;
4439 
4440 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
4441 			op->status = nfserr_rep_too_big_to_cache;
4442 		else
4443 			op->status = nfserr_rep_too_big;
4444 	}
4445 	if (op->status == nfserr_resource ||
4446 	    op->status == nfserr_rep_too_big ||
4447 	    op->status == nfserr_rep_too_big_to_cache) {
4448 		/*
4449 		 * The operation may have already been encoded or
4450 		 * partially encoded.  No op returns anything additional
4451 		 * in the case of one of these three errors, so we can
4452 		 * just truncate back to after the status.  But it's a
4453 		 * bug if we had to do this on a non-idempotent op:
4454 		 */
4455 		warn_on_nonidempotent_op(op);
4456 		xdr_truncate_encode(xdr, post_err_offset);
4457 	}
4458 	if (so) {
4459 		int len = xdr->buf->len - post_err_offset;
4460 
4461 		so->so_replay.rp_status = op->status;
4462 		so->so_replay.rp_buflen = len;
4463 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
4464 						so->so_replay.rp_buf, len);
4465 	}
4466 status:
4467 	/* Note that op->status is already in network byte order: */
4468 	write_bytes_to_xdr_buf(xdr->buf, post_err_offset - 4, &op->status, 4);
4469 }
4470 
4471 /*
4472  * Encode the reply stored in the stateowner reply cache
4473  *
4474  * XDR note: do not encode rp->rp_buflen: the buffer contains the
4475  * previously sent already encoded operation.
4476  */
4477 void
4478 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
4479 {
4480 	__be32 *p;
4481 	struct nfs4_replay *rp = op->replay;
4482 
4483 	BUG_ON(!rp);
4484 
4485 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
4486 	if (!p) {
4487 		WARN_ON_ONCE(1);
4488 		return;
4489 	}
4490 	*p++ = cpu_to_be32(op->opnum);
4491 	*p++ = rp->rp_status;  /* already xdr'ed */
4492 
4493 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
4494 }
4495 
4496 int
4497 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p)
4498 {
4499         return xdr_ressize_check(rqstp, p);
4500 }
4501 
4502 void nfsd4_release_compoundargs(struct svc_rqst *rqstp)
4503 {
4504 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4505 
4506 	if (args->ops != args->iops) {
4507 		kfree(args->ops);
4508 		args->ops = args->iops;
4509 	}
4510 	kfree(args->tmpp);
4511 	args->tmpp = NULL;
4512 	while (args->to_free) {
4513 		struct svcxdr_tmpbuf *tb = args->to_free;
4514 		args->to_free = tb->next;
4515 		kfree(tb);
4516 	}
4517 }
4518 
4519 int
4520 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p)
4521 {
4522 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4523 
4524 	if (rqstp->rq_arg.head[0].iov_len % 4) {
4525 		/* client is nuts */
4526 		dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)",
4527 			__func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid));
4528 		return 0;
4529 	}
4530 	args->p = p;
4531 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
4532 	args->pagelist = rqstp->rq_arg.pages;
4533 	args->pagelen = rqstp->rq_arg.page_len;
4534 	args->tail = false;
4535 	args->tmpp = NULL;
4536 	args->to_free = NULL;
4537 	args->ops = args->iops;
4538 	args->rqstp = rqstp;
4539 
4540 	return !nfsd4_decode_compound(args);
4541 }
4542 
4543 int
4544 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p)
4545 {
4546 	/*
4547 	 * All that remains is to write the tag and operation count...
4548 	 */
4549 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
4550 	struct xdr_buf *buf = resp->xdr.buf;
4551 
4552 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
4553 				 buf->tail[0].iov_len);
4554 
4555 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
4556 
4557 	p = resp->tagp;
4558 	*p++ = htonl(resp->taglen);
4559 	memcpy(p, resp->tag, resp->taglen);
4560 	p += XDR_QUADLEN(resp->taglen);
4561 	*p++ = htonl(resp->opcnt);
4562 
4563 	nfsd4_sequence_done(resp);
4564 	return 1;
4565 }
4566 
4567 /*
4568  * Local variables:
4569  *  c-basic-offset: 8
4570  * End:
4571  */
4572