xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision aac5987a)
1 /*
2  *  Server-side XDR for NFSv4
3  *
4  *  Copyright (c) 2002 The Regents of the University of Michigan.
5  *  All rights reserved.
6  *
7  *  Kendrick Smith <kmsmith@umich.edu>
8  *  Andy Adamson   <andros@umich.edu>
9  *
10  *  Redistribution and use in source and binary forms, with or without
11  *  modification, are permitted provided that the following conditions
12  *  are met:
13  *
14  *  1. Redistributions of source code must retain the above copyright
15  *     notice, this list of conditions and the following disclaimer.
16  *  2. Redistributions in binary form must reproduce the above copyright
17  *     notice, this list of conditions and the following disclaimer in the
18  *     documentation and/or other materials provided with the distribution.
19  *  3. Neither the name of the University nor the names of its
20  *     contributors may be used to endorse or promote products derived
21  *     from this software without specific prior written permission.
22  *
23  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
24  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
30  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 #include <linux/fs_struct.h>
37 #include <linux/file.h>
38 #include <linux/slab.h>
39 #include <linux/namei.h>
40 #include <linux/statfs.h>
41 #include <linux/utsname.h>
42 #include <linux/pagemap.h>
43 #include <linux/sunrpc/svcauth_gss.h>
44 
45 #include "idmap.h"
46 #include "acl.h"
47 #include "xdr4.h"
48 #include "vfs.h"
49 #include "state.h"
50 #include "cache.h"
51 #include "netns.h"
52 #include "pnfs.h"
53 
54 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
55 #include <linux/security.h>
56 #endif
57 
58 
59 #define NFSDDBG_FACILITY		NFSDDBG_XDR
60 
61 const u32 nfsd_suppattrs[3][3] = {
62 	{NFSD4_SUPPORTED_ATTRS_WORD0,
63 	 NFSD4_SUPPORTED_ATTRS_WORD1,
64 	 NFSD4_SUPPORTED_ATTRS_WORD2},
65 
66 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
67 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
68 	 NFSD4_1_SUPPORTED_ATTRS_WORD2},
69 
70 	{NFSD4_1_SUPPORTED_ATTRS_WORD0,
71 	 NFSD4_1_SUPPORTED_ATTRS_WORD1,
72 	 NFSD4_2_SUPPORTED_ATTRS_WORD2},
73 };
74 
75 /*
76  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
77  * directory in order to indicate to the client that a filesystem boundary is present
78  * We use a fixed fsid for a referral
79  */
80 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
81 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
82 
83 static __be32
84 check_filename(char *str, int len)
85 {
86 	int i;
87 
88 	if (len == 0)
89 		return nfserr_inval;
90 	if (isdotent(str, len))
91 		return nfserr_badname;
92 	for (i = 0; i < len; i++)
93 		if (str[i] == '/')
94 			return nfserr_badname;
95 	return 0;
96 }
97 
98 #define DECODE_HEAD				\
99 	__be32 *p;				\
100 	__be32 status
101 #define DECODE_TAIL				\
102 	status = 0;				\
103 out:						\
104 	return status;				\
105 xdr_error:					\
106 	dprintk("NFSD: xdr error (%s:%d)\n",	\
107 			__FILE__, __LINE__);	\
108 	status = nfserr_bad_xdr;		\
109 	goto out
110 
111 #define READMEM(x,nbytes) do {			\
112 	x = (char *)p;				\
113 	p += XDR_QUADLEN(nbytes);		\
114 } while (0)
115 #define SAVEMEM(x,nbytes) do {			\
116 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
117  		savemem(argp, p, nbytes) :	\
118  		(char *)p)) {			\
119 		dprintk("NFSD: xdr error (%s:%d)\n", \
120 				__FILE__, __LINE__); \
121 		goto xdr_error;			\
122 		}				\
123 	p += XDR_QUADLEN(nbytes);		\
124 } while (0)
125 #define COPYMEM(x,nbytes) do {			\
126 	memcpy((x), p, nbytes);			\
127 	p += XDR_QUADLEN(nbytes);		\
128 } while (0)
129 
130 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
131 #define READ_BUF(nbytes)  do {			\
132 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
133 		p = argp->p;			\
134 		argp->p += XDR_QUADLEN(nbytes);	\
135 	} else if (!(p = read_buf(argp, nbytes))) { \
136 		dprintk("NFSD: xdr error (%s:%d)\n", \
137 				__FILE__, __LINE__); \
138 		goto xdr_error;			\
139 	}					\
140 } while (0)
141 
142 static void next_decode_page(struct nfsd4_compoundargs *argp)
143 {
144 	argp->p = page_address(argp->pagelist[0]);
145 	argp->pagelist++;
146 	if (argp->pagelen < PAGE_SIZE) {
147 		argp->end = argp->p + (argp->pagelen>>2);
148 		argp->pagelen = 0;
149 	} else {
150 		argp->end = argp->p + (PAGE_SIZE>>2);
151 		argp->pagelen -= PAGE_SIZE;
152 	}
153 }
154 
155 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
156 {
157 	/* We want more bytes than seem to be available.
158 	 * Maybe we need a new page, maybe we have just run out
159 	 */
160 	unsigned int avail = (char *)argp->end - (char *)argp->p;
161 	__be32 *p;
162 	if (avail + argp->pagelen < nbytes)
163 		return NULL;
164 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
165 		return NULL;
166 	/* ok, we can do it with the current plus the next page */
167 	if (nbytes <= sizeof(argp->tmp))
168 		p = argp->tmp;
169 	else {
170 		kfree(argp->tmpp);
171 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
172 		if (!p)
173 			return NULL;
174 
175 	}
176 	/*
177 	 * The following memcpy is safe because read_buf is always
178 	 * called with nbytes > avail, and the two cases above both
179 	 * guarantee p points to at least nbytes bytes.
180 	 */
181 	memcpy(p, argp->p, avail);
182 	next_decode_page(argp);
183 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
184 	argp->p += XDR_QUADLEN(nbytes - avail);
185 	return p;
186 }
187 
188 static int zero_clientid(clientid_t *clid)
189 {
190 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
191 }
192 
193 /**
194  * svcxdr_tmpalloc - allocate memory to be freed after compound processing
195  * @argp: NFSv4 compound argument structure
196  * @p: pointer to be freed (with kfree())
197  *
198  * Marks @p to be freed when processing the compound operation
199  * described in @argp finishes.
200  */
201 static void *
202 svcxdr_tmpalloc(struct nfsd4_compoundargs *argp, u32 len)
203 {
204 	struct svcxdr_tmpbuf *tb;
205 
206 	tb = kmalloc(sizeof(*tb) + len, GFP_KERNEL);
207 	if (!tb)
208 		return NULL;
209 	tb->next = argp->to_free;
210 	argp->to_free = tb;
211 	return tb->buf;
212 }
213 
214 /*
215  * For xdr strings that need to be passed to other kernel api's
216  * as null-terminated strings.
217  *
218  * Note null-terminating in place usually isn't safe since the
219  * buffer might end on a page boundary.
220  */
221 static char *
222 svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len)
223 {
224 	char *p = svcxdr_tmpalloc(argp, len + 1);
225 
226 	if (!p)
227 		return NULL;
228 	memcpy(p, buf, len);
229 	p[len] = '\0';
230 	return p;
231 }
232 
233 /**
234  * savemem - duplicate a chunk of memory for later processing
235  * @argp: NFSv4 compound argument structure to be freed with
236  * @p: pointer to be duplicated
237  * @nbytes: length to be duplicated
238  *
239  * Returns a pointer to a copy of @nbytes bytes of memory at @p
240  * that are preserved until processing of the NFSv4 compound
241  * operation described by @argp finishes.
242  */
243 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
244 {
245 	void *ret;
246 
247 	ret = svcxdr_tmpalloc(argp, nbytes);
248 	if (!ret)
249 		return NULL;
250 	memcpy(ret, p, nbytes);
251 	return ret;
252 }
253 
254 /*
255  * We require the high 32 bits of 'seconds' to be 0, and
256  * we ignore all 32 bits of 'nseconds'.
257  */
258 static __be32
259 nfsd4_decode_time(struct nfsd4_compoundargs *argp, struct timespec *tv)
260 {
261 	DECODE_HEAD;
262 	u64 sec;
263 
264 	READ_BUF(12);
265 	p = xdr_decode_hyper(p, &sec);
266 	tv->tv_sec = sec;
267 	tv->tv_nsec = be32_to_cpup(p++);
268 	if (tv->tv_nsec >= (u32)1000000000)
269 		return nfserr_inval;
270 
271 	DECODE_TAIL;
272 }
273 
274 static __be32
275 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
276 {
277 	u32 bmlen;
278 	DECODE_HEAD;
279 
280 	bmval[0] = 0;
281 	bmval[1] = 0;
282 	bmval[2] = 0;
283 
284 	READ_BUF(4);
285 	bmlen = be32_to_cpup(p++);
286 	if (bmlen > 1000)
287 		goto xdr_error;
288 
289 	READ_BUF(bmlen << 2);
290 	if (bmlen > 0)
291 		bmval[0] = be32_to_cpup(p++);
292 	if (bmlen > 1)
293 		bmval[1] = be32_to_cpup(p++);
294 	if (bmlen > 2)
295 		bmval[2] = be32_to_cpup(p++);
296 
297 	DECODE_TAIL;
298 }
299 
300 static __be32
301 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
302 		   struct iattr *iattr, struct nfs4_acl **acl,
303 		   struct xdr_netobj *label, int *umask)
304 {
305 	int expected_len, len = 0;
306 	u32 dummy32;
307 	char *buf;
308 
309 	DECODE_HEAD;
310 	iattr->ia_valid = 0;
311 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
312 		return status;
313 
314 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
315 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
316 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2) {
317 		if (nfsd_attrs_supported(argp->minorversion, bmval))
318 			return nfserr_inval;
319 		return nfserr_attrnotsupp;
320 	}
321 
322 	READ_BUF(4);
323 	expected_len = be32_to_cpup(p++);
324 
325 	if (bmval[0] & FATTR4_WORD0_SIZE) {
326 		READ_BUF(8);
327 		len += 8;
328 		p = xdr_decode_hyper(p, &iattr->ia_size);
329 		iattr->ia_valid |= ATTR_SIZE;
330 	}
331 	if (bmval[0] & FATTR4_WORD0_ACL) {
332 		u32 nace;
333 		struct nfs4_ace *ace;
334 
335 		READ_BUF(4); len += 4;
336 		nace = be32_to_cpup(p++);
337 
338 		if (nace > NFS4_ACL_MAX)
339 			return nfserr_fbig;
340 
341 		*acl = svcxdr_tmpalloc(argp, nfs4_acl_bytes(nace));
342 		if (*acl == NULL)
343 			return nfserr_jukebox;
344 
345 		(*acl)->naces = nace;
346 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
347 			READ_BUF(16); len += 16;
348 			ace->type = be32_to_cpup(p++);
349 			ace->flag = be32_to_cpup(p++);
350 			ace->access_mask = be32_to_cpup(p++);
351 			dummy32 = be32_to_cpup(p++);
352 			READ_BUF(dummy32);
353 			len += XDR_QUADLEN(dummy32) << 2;
354 			READMEM(buf, dummy32);
355 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
356 			status = nfs_ok;
357 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
358 				;
359 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
360 				status = nfsd_map_name_to_gid(argp->rqstp,
361 						buf, dummy32, &ace->who_gid);
362 			else
363 				status = nfsd_map_name_to_uid(argp->rqstp,
364 						buf, dummy32, &ace->who_uid);
365 			if (status)
366 				return status;
367 		}
368 	} else
369 		*acl = NULL;
370 	if (bmval[1] & FATTR4_WORD1_MODE) {
371 		READ_BUF(4);
372 		len += 4;
373 		iattr->ia_mode = be32_to_cpup(p++);
374 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
375 		iattr->ia_valid |= ATTR_MODE;
376 	}
377 	if (bmval[1] & FATTR4_WORD1_OWNER) {
378 		READ_BUF(4);
379 		len += 4;
380 		dummy32 = be32_to_cpup(p++);
381 		READ_BUF(dummy32);
382 		len += (XDR_QUADLEN(dummy32) << 2);
383 		READMEM(buf, dummy32);
384 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
385 			return status;
386 		iattr->ia_valid |= ATTR_UID;
387 	}
388 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
389 		READ_BUF(4);
390 		len += 4;
391 		dummy32 = be32_to_cpup(p++);
392 		READ_BUF(dummy32);
393 		len += (XDR_QUADLEN(dummy32) << 2);
394 		READMEM(buf, dummy32);
395 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
396 			return status;
397 		iattr->ia_valid |= ATTR_GID;
398 	}
399 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
400 		READ_BUF(4);
401 		len += 4;
402 		dummy32 = be32_to_cpup(p++);
403 		switch (dummy32) {
404 		case NFS4_SET_TO_CLIENT_TIME:
405 			len += 12;
406 			status = nfsd4_decode_time(argp, &iattr->ia_atime);
407 			if (status)
408 				return status;
409 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
410 			break;
411 		case NFS4_SET_TO_SERVER_TIME:
412 			iattr->ia_valid |= ATTR_ATIME;
413 			break;
414 		default:
415 			goto xdr_error;
416 		}
417 	}
418 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
419 		READ_BUF(4);
420 		len += 4;
421 		dummy32 = be32_to_cpup(p++);
422 		switch (dummy32) {
423 		case NFS4_SET_TO_CLIENT_TIME:
424 			len += 12;
425 			status = nfsd4_decode_time(argp, &iattr->ia_mtime);
426 			if (status)
427 				return status;
428 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
429 			break;
430 		case NFS4_SET_TO_SERVER_TIME:
431 			iattr->ia_valid |= ATTR_MTIME;
432 			break;
433 		default:
434 			goto xdr_error;
435 		}
436 	}
437 
438 	label->len = 0;
439 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
440 	if (bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
441 		READ_BUF(4);
442 		len += 4;
443 		dummy32 = be32_to_cpup(p++); /* lfs: we don't use it */
444 		READ_BUF(4);
445 		len += 4;
446 		dummy32 = be32_to_cpup(p++); /* pi: we don't use it either */
447 		READ_BUF(4);
448 		len += 4;
449 		dummy32 = be32_to_cpup(p++);
450 		READ_BUF(dummy32);
451 		if (dummy32 > NFS4_MAXLABELLEN)
452 			return nfserr_badlabel;
453 		len += (XDR_QUADLEN(dummy32) << 2);
454 		READMEM(buf, dummy32);
455 		label->len = dummy32;
456 		label->data = svcxdr_dupstr(argp, buf, dummy32);
457 		if (!label->data)
458 			return nfserr_jukebox;
459 	}
460 #endif
461 	if (bmval[2] & FATTR4_WORD2_MODE_UMASK) {
462 		if (!umask)
463 			goto xdr_error;
464 		READ_BUF(8);
465 		len += 8;
466 		dummy32 = be32_to_cpup(p++);
467 		iattr->ia_mode = dummy32 & (S_IFMT | S_IALLUGO);
468 		dummy32 = be32_to_cpup(p++);
469 		*umask = dummy32 & S_IRWXUGO;
470 		iattr->ia_valid |= ATTR_MODE;
471 	}
472 	if (len != expected_len)
473 		goto xdr_error;
474 
475 	DECODE_TAIL;
476 }
477 
478 static __be32
479 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
480 {
481 	DECODE_HEAD;
482 
483 	READ_BUF(sizeof(stateid_t));
484 	sid->si_generation = be32_to_cpup(p++);
485 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
486 
487 	DECODE_TAIL;
488 }
489 
490 static __be32
491 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
492 {
493 	DECODE_HEAD;
494 
495 	READ_BUF(4);
496 	access->ac_req_access = be32_to_cpup(p++);
497 
498 	DECODE_TAIL;
499 }
500 
501 static __be32 nfsd4_decode_cb_sec(struct nfsd4_compoundargs *argp, struct nfsd4_cb_sec *cbs)
502 {
503 	DECODE_HEAD;
504 	u32 dummy, uid, gid;
505 	char *machine_name;
506 	int i;
507 	int nr_secflavs;
508 
509 	/* callback_sec_params4 */
510 	READ_BUF(4);
511 	nr_secflavs = be32_to_cpup(p++);
512 	if (nr_secflavs)
513 		cbs->flavor = (u32)(-1);
514 	else
515 		/* Is this legal? Be generous, take it to mean AUTH_NONE: */
516 		cbs->flavor = 0;
517 	for (i = 0; i < nr_secflavs; ++i) {
518 		READ_BUF(4);
519 		dummy = be32_to_cpup(p++);
520 		switch (dummy) {
521 		case RPC_AUTH_NULL:
522 			/* Nothing to read */
523 			if (cbs->flavor == (u32)(-1))
524 				cbs->flavor = RPC_AUTH_NULL;
525 			break;
526 		case RPC_AUTH_UNIX:
527 			READ_BUF(8);
528 			/* stamp */
529 			dummy = be32_to_cpup(p++);
530 
531 			/* machine name */
532 			dummy = be32_to_cpup(p++);
533 			READ_BUF(dummy);
534 			SAVEMEM(machine_name, dummy);
535 
536 			/* uid, gid */
537 			READ_BUF(8);
538 			uid = be32_to_cpup(p++);
539 			gid = be32_to_cpup(p++);
540 
541 			/* more gids */
542 			READ_BUF(4);
543 			dummy = be32_to_cpup(p++);
544 			READ_BUF(dummy * 4);
545 			if (cbs->flavor == (u32)(-1)) {
546 				kuid_t kuid = make_kuid(&init_user_ns, uid);
547 				kgid_t kgid = make_kgid(&init_user_ns, gid);
548 				if (uid_valid(kuid) && gid_valid(kgid)) {
549 					cbs->uid = kuid;
550 					cbs->gid = kgid;
551 					cbs->flavor = RPC_AUTH_UNIX;
552 				} else {
553 					dprintk("RPC_AUTH_UNIX with invalid"
554 						"uid or gid ignoring!\n");
555 				}
556 			}
557 			break;
558 		case RPC_AUTH_GSS:
559 			dprintk("RPC_AUTH_GSS callback secflavor "
560 				"not supported!\n");
561 			READ_BUF(8);
562 			/* gcbp_service */
563 			dummy = be32_to_cpup(p++);
564 			/* gcbp_handle_from_server */
565 			dummy = be32_to_cpup(p++);
566 			READ_BUF(dummy);
567 			p += XDR_QUADLEN(dummy);
568 			/* gcbp_handle_from_client */
569 			READ_BUF(4);
570 			dummy = be32_to_cpup(p++);
571 			READ_BUF(dummy);
572 			break;
573 		default:
574 			dprintk("Illegal callback secflavor\n");
575 			return nfserr_inval;
576 		}
577 	}
578 	DECODE_TAIL;
579 }
580 
581 static __be32 nfsd4_decode_backchannel_ctl(struct nfsd4_compoundargs *argp, struct nfsd4_backchannel_ctl *bc)
582 {
583 	DECODE_HEAD;
584 
585 	READ_BUF(4);
586 	bc->bc_cb_program = be32_to_cpup(p++);
587 	nfsd4_decode_cb_sec(argp, &bc->bc_cb_sec);
588 
589 	DECODE_TAIL;
590 }
591 
592 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
593 {
594 	DECODE_HEAD;
595 
596 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
597 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
598 	bcts->dir = be32_to_cpup(p++);
599 	/* XXX: skipping ctsa_use_conn_in_rdma_mode.  Perhaps Tom Tucker
600 	 * could help us figure out we should be using it. */
601 	DECODE_TAIL;
602 }
603 
604 static __be32
605 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
606 {
607 	DECODE_HEAD;
608 
609 	READ_BUF(4);
610 	close->cl_seqid = be32_to_cpup(p++);
611 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
612 
613 	DECODE_TAIL;
614 }
615 
616 
617 static __be32
618 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
619 {
620 	DECODE_HEAD;
621 
622 	READ_BUF(12);
623 	p = xdr_decode_hyper(p, &commit->co_offset);
624 	commit->co_count = be32_to_cpup(p++);
625 
626 	DECODE_TAIL;
627 }
628 
629 static __be32
630 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
631 {
632 	DECODE_HEAD;
633 
634 	READ_BUF(4);
635 	create->cr_type = be32_to_cpup(p++);
636 	switch (create->cr_type) {
637 	case NF4LNK:
638 		READ_BUF(4);
639 		create->cr_datalen = be32_to_cpup(p++);
640 		READ_BUF(create->cr_datalen);
641 		create->cr_data = svcxdr_dupstr(argp, p, create->cr_datalen);
642 		if (!create->cr_data)
643 			return nfserr_jukebox;
644 		break;
645 	case NF4BLK:
646 	case NF4CHR:
647 		READ_BUF(8);
648 		create->cr_specdata1 = be32_to_cpup(p++);
649 		create->cr_specdata2 = be32_to_cpup(p++);
650 		break;
651 	case NF4SOCK:
652 	case NF4FIFO:
653 	case NF4DIR:
654 	default:
655 		break;
656 	}
657 
658 	READ_BUF(4);
659 	create->cr_namelen = be32_to_cpup(p++);
660 	READ_BUF(create->cr_namelen);
661 	SAVEMEM(create->cr_name, create->cr_namelen);
662 	if ((status = check_filename(create->cr_name, create->cr_namelen)))
663 		return status;
664 
665 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
666 				    &create->cr_acl, &create->cr_label,
667 				    &current->fs->umask);
668 	if (status)
669 		goto out;
670 
671 	DECODE_TAIL;
672 }
673 
674 static inline __be32
675 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
676 {
677 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
678 }
679 
680 static inline __be32
681 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
682 {
683 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
684 }
685 
686 static __be32
687 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
688 {
689 	DECODE_HEAD;
690 
691 	READ_BUF(4);
692 	link->li_namelen = be32_to_cpup(p++);
693 	READ_BUF(link->li_namelen);
694 	SAVEMEM(link->li_name, link->li_namelen);
695 	if ((status = check_filename(link->li_name, link->li_namelen)))
696 		return status;
697 
698 	DECODE_TAIL;
699 }
700 
701 static __be32
702 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
703 {
704 	DECODE_HEAD;
705 
706 	/*
707 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
708 	*/
709 	READ_BUF(28);
710 	lock->lk_type = be32_to_cpup(p++);
711 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
712 		goto xdr_error;
713 	lock->lk_reclaim = be32_to_cpup(p++);
714 	p = xdr_decode_hyper(p, &lock->lk_offset);
715 	p = xdr_decode_hyper(p, &lock->lk_length);
716 	lock->lk_is_new = be32_to_cpup(p++);
717 
718 	if (lock->lk_is_new) {
719 		READ_BUF(4);
720 		lock->lk_new_open_seqid = be32_to_cpup(p++);
721 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
722 		if (status)
723 			return status;
724 		READ_BUF(8 + sizeof(clientid_t));
725 		lock->lk_new_lock_seqid = be32_to_cpup(p++);
726 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
727 		lock->lk_new_owner.len = be32_to_cpup(p++);
728 		READ_BUF(lock->lk_new_owner.len);
729 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
730 	} else {
731 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
732 		if (status)
733 			return status;
734 		READ_BUF(4);
735 		lock->lk_old_lock_seqid = be32_to_cpup(p++);
736 	}
737 
738 	DECODE_TAIL;
739 }
740 
741 static __be32
742 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
743 {
744 	DECODE_HEAD;
745 
746 	READ_BUF(32);
747 	lockt->lt_type = be32_to_cpup(p++);
748 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
749 		goto xdr_error;
750 	p = xdr_decode_hyper(p, &lockt->lt_offset);
751 	p = xdr_decode_hyper(p, &lockt->lt_length);
752 	COPYMEM(&lockt->lt_clientid, 8);
753 	lockt->lt_owner.len = be32_to_cpup(p++);
754 	READ_BUF(lockt->lt_owner.len);
755 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
756 
757 	DECODE_TAIL;
758 }
759 
760 static __be32
761 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
762 {
763 	DECODE_HEAD;
764 
765 	READ_BUF(8);
766 	locku->lu_type = be32_to_cpup(p++);
767 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
768 		goto xdr_error;
769 	locku->lu_seqid = be32_to_cpup(p++);
770 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
771 	if (status)
772 		return status;
773 	READ_BUF(16);
774 	p = xdr_decode_hyper(p, &locku->lu_offset);
775 	p = xdr_decode_hyper(p, &locku->lu_length);
776 
777 	DECODE_TAIL;
778 }
779 
780 static __be32
781 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
782 {
783 	DECODE_HEAD;
784 
785 	READ_BUF(4);
786 	lookup->lo_len = be32_to_cpup(p++);
787 	READ_BUF(lookup->lo_len);
788 	SAVEMEM(lookup->lo_name, lookup->lo_len);
789 	if ((status = check_filename(lookup->lo_name, lookup->lo_len)))
790 		return status;
791 
792 	DECODE_TAIL;
793 }
794 
795 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
796 {
797 	__be32 *p;
798 	u32 w;
799 
800 	READ_BUF(4);
801 	w = be32_to_cpup(p++);
802 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
803 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
804 	if (deleg_when)
805 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
806 
807 	switch (w & NFS4_SHARE_ACCESS_MASK) {
808 	case NFS4_SHARE_ACCESS_READ:
809 	case NFS4_SHARE_ACCESS_WRITE:
810 	case NFS4_SHARE_ACCESS_BOTH:
811 		break;
812 	default:
813 		return nfserr_bad_xdr;
814 	}
815 	w &= ~NFS4_SHARE_ACCESS_MASK;
816 	if (!w)
817 		return nfs_ok;
818 	if (!argp->minorversion)
819 		return nfserr_bad_xdr;
820 	switch (w & NFS4_SHARE_WANT_MASK) {
821 	case NFS4_SHARE_WANT_NO_PREFERENCE:
822 	case NFS4_SHARE_WANT_READ_DELEG:
823 	case NFS4_SHARE_WANT_WRITE_DELEG:
824 	case NFS4_SHARE_WANT_ANY_DELEG:
825 	case NFS4_SHARE_WANT_NO_DELEG:
826 	case NFS4_SHARE_WANT_CANCEL:
827 		break;
828 	default:
829 		return nfserr_bad_xdr;
830 	}
831 	w &= ~NFS4_SHARE_WANT_MASK;
832 	if (!w)
833 		return nfs_ok;
834 
835 	if (!deleg_when)	/* open_downgrade */
836 		return nfserr_inval;
837 	switch (w) {
838 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
839 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
840 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
841 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
842 		return nfs_ok;
843 	}
844 xdr_error:
845 	return nfserr_bad_xdr;
846 }
847 
848 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
849 {
850 	__be32 *p;
851 
852 	READ_BUF(4);
853 	*x = be32_to_cpup(p++);
854 	/* Note: unlinke access bits, deny bits may be zero. */
855 	if (*x & ~NFS4_SHARE_DENY_BOTH)
856 		return nfserr_bad_xdr;
857 	return nfs_ok;
858 xdr_error:
859 	return nfserr_bad_xdr;
860 }
861 
862 static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
863 {
864 	__be32 *p;
865 
866 	READ_BUF(4);
867 	o->len = be32_to_cpup(p++);
868 
869 	if (o->len == 0 || o->len > NFS4_OPAQUE_LIMIT)
870 		return nfserr_bad_xdr;
871 
872 	READ_BUF(o->len);
873 	SAVEMEM(o->data, o->len);
874 	return nfs_ok;
875 xdr_error:
876 	return nfserr_bad_xdr;
877 }
878 
879 static __be32
880 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
881 {
882 	DECODE_HEAD;
883 	u32 dummy;
884 
885 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
886 	open->op_iattr.ia_valid = 0;
887 	open->op_openowner = NULL;
888 
889 	open->op_xdr_error = 0;
890 	/* seqid, share_access, share_deny, clientid, ownerlen */
891 	READ_BUF(4);
892 	open->op_seqid = be32_to_cpup(p++);
893 	/* decode, yet ignore deleg_when until supported */
894 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
895 					   &open->op_deleg_want, &dummy);
896 	if (status)
897 		goto xdr_error;
898 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
899 	if (status)
900 		goto xdr_error;
901 	READ_BUF(sizeof(clientid_t));
902 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
903 	status = nfsd4_decode_opaque(argp, &open->op_owner);
904 	if (status)
905 		goto xdr_error;
906 	READ_BUF(4);
907 	open->op_create = be32_to_cpup(p++);
908 	switch (open->op_create) {
909 	case NFS4_OPEN_NOCREATE:
910 		break;
911 	case NFS4_OPEN_CREATE:
912 		current->fs->umask = 0;
913 		READ_BUF(4);
914 		open->op_createmode = be32_to_cpup(p++);
915 		switch (open->op_createmode) {
916 		case NFS4_CREATE_UNCHECKED:
917 		case NFS4_CREATE_GUARDED:
918 			status = nfsd4_decode_fattr(argp, open->op_bmval,
919 				&open->op_iattr, &open->op_acl, &open->op_label,
920 				&current->fs->umask);
921 			if (status)
922 				goto out;
923 			break;
924 		case NFS4_CREATE_EXCLUSIVE:
925 			READ_BUF(NFS4_VERIFIER_SIZE);
926 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
927 			break;
928 		case NFS4_CREATE_EXCLUSIVE4_1:
929 			if (argp->minorversion < 1)
930 				goto xdr_error;
931 			READ_BUF(NFS4_VERIFIER_SIZE);
932 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
933 			status = nfsd4_decode_fattr(argp, open->op_bmval,
934 				&open->op_iattr, &open->op_acl, &open->op_label,
935 				&current->fs->umask);
936 			if (status)
937 				goto out;
938 			break;
939 		default:
940 			goto xdr_error;
941 		}
942 		break;
943 	default:
944 		goto xdr_error;
945 	}
946 
947 	/* open_claim */
948 	READ_BUF(4);
949 	open->op_claim_type = be32_to_cpup(p++);
950 	switch (open->op_claim_type) {
951 	case NFS4_OPEN_CLAIM_NULL:
952 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
953 		READ_BUF(4);
954 		open->op_fname.len = be32_to_cpup(p++);
955 		READ_BUF(open->op_fname.len);
956 		SAVEMEM(open->op_fname.data, open->op_fname.len);
957 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
958 			return status;
959 		break;
960 	case NFS4_OPEN_CLAIM_PREVIOUS:
961 		READ_BUF(4);
962 		open->op_delegate_type = be32_to_cpup(p++);
963 		break;
964 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
965 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
966 		if (status)
967 			return status;
968 		READ_BUF(4);
969 		open->op_fname.len = be32_to_cpup(p++);
970 		READ_BUF(open->op_fname.len);
971 		SAVEMEM(open->op_fname.data, open->op_fname.len);
972 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
973 			return status;
974 		break;
975 	case NFS4_OPEN_CLAIM_FH:
976 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
977 		if (argp->minorversion < 1)
978 			goto xdr_error;
979 		/* void */
980 		break;
981 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
982 		if (argp->minorversion < 1)
983 			goto xdr_error;
984 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
985 		if (status)
986 			return status;
987 		break;
988 	default:
989 		goto xdr_error;
990 	}
991 
992 	DECODE_TAIL;
993 }
994 
995 static __be32
996 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
997 {
998 	DECODE_HEAD;
999 
1000 	if (argp->minorversion >= 1)
1001 		return nfserr_notsupp;
1002 
1003 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
1004 	if (status)
1005 		return status;
1006 	READ_BUF(4);
1007 	open_conf->oc_seqid = be32_to_cpup(p++);
1008 
1009 	DECODE_TAIL;
1010 }
1011 
1012 static __be32
1013 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
1014 {
1015 	DECODE_HEAD;
1016 
1017 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
1018 	if (status)
1019 		return status;
1020 	READ_BUF(4);
1021 	open_down->od_seqid = be32_to_cpup(p++);
1022 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
1023 					   &open_down->od_deleg_want, NULL);
1024 	if (status)
1025 		return status;
1026 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
1027 	if (status)
1028 		return status;
1029 	DECODE_TAIL;
1030 }
1031 
1032 static __be32
1033 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
1034 {
1035 	DECODE_HEAD;
1036 
1037 	READ_BUF(4);
1038 	putfh->pf_fhlen = be32_to_cpup(p++);
1039 	if (putfh->pf_fhlen > NFS4_FHSIZE)
1040 		goto xdr_error;
1041 	READ_BUF(putfh->pf_fhlen);
1042 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
1043 
1044 	DECODE_TAIL;
1045 }
1046 
1047 static __be32
1048 nfsd4_decode_putpubfh(struct nfsd4_compoundargs *argp, void *p)
1049 {
1050 	if (argp->minorversion == 0)
1051 		return nfs_ok;
1052 	return nfserr_notsupp;
1053 }
1054 
1055 static __be32
1056 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
1057 {
1058 	DECODE_HEAD;
1059 
1060 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
1061 	if (status)
1062 		return status;
1063 	READ_BUF(12);
1064 	p = xdr_decode_hyper(p, &read->rd_offset);
1065 	read->rd_length = be32_to_cpup(p++);
1066 
1067 	DECODE_TAIL;
1068 }
1069 
1070 static __be32
1071 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
1072 {
1073 	DECODE_HEAD;
1074 
1075 	READ_BUF(24);
1076 	p = xdr_decode_hyper(p, &readdir->rd_cookie);
1077 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
1078 	readdir->rd_dircount = be32_to_cpup(p++);
1079 	readdir->rd_maxcount = be32_to_cpup(p++);
1080 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
1081 		goto out;
1082 
1083 	DECODE_TAIL;
1084 }
1085 
1086 static __be32
1087 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
1088 {
1089 	DECODE_HEAD;
1090 
1091 	READ_BUF(4);
1092 	remove->rm_namelen = be32_to_cpup(p++);
1093 	READ_BUF(remove->rm_namelen);
1094 	SAVEMEM(remove->rm_name, remove->rm_namelen);
1095 	if ((status = check_filename(remove->rm_name, remove->rm_namelen)))
1096 		return status;
1097 
1098 	DECODE_TAIL;
1099 }
1100 
1101 static __be32
1102 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
1103 {
1104 	DECODE_HEAD;
1105 
1106 	READ_BUF(4);
1107 	rename->rn_snamelen = be32_to_cpup(p++);
1108 	READ_BUF(rename->rn_snamelen);
1109 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1110 	READ_BUF(4);
1111 	rename->rn_tnamelen = be32_to_cpup(p++);
1112 	READ_BUF(rename->rn_tnamelen);
1113 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1114 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1115 		return status;
1116 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1117 		return status;
1118 
1119 	DECODE_TAIL;
1120 }
1121 
1122 static __be32
1123 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1124 {
1125 	DECODE_HEAD;
1126 
1127 	if (argp->minorversion >= 1)
1128 		return nfserr_notsupp;
1129 
1130 	READ_BUF(sizeof(clientid_t));
1131 	COPYMEM(clientid, sizeof(clientid_t));
1132 
1133 	DECODE_TAIL;
1134 }
1135 
1136 static __be32
1137 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1138 		     struct nfsd4_secinfo *secinfo)
1139 {
1140 	DECODE_HEAD;
1141 
1142 	READ_BUF(4);
1143 	secinfo->si_namelen = be32_to_cpup(p++);
1144 	READ_BUF(secinfo->si_namelen);
1145 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1146 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1147 	if (status)
1148 		return status;
1149 	DECODE_TAIL;
1150 }
1151 
1152 static __be32
1153 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1154 		     struct nfsd4_secinfo_no_name *sin)
1155 {
1156 	DECODE_HEAD;
1157 
1158 	READ_BUF(4);
1159 	sin->sin_style = be32_to_cpup(p++);
1160 	DECODE_TAIL;
1161 }
1162 
1163 static __be32
1164 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1165 {
1166 	__be32 status;
1167 
1168 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1169 	if (status)
1170 		return status;
1171 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1172 				  &setattr->sa_acl, &setattr->sa_label, NULL);
1173 }
1174 
1175 static __be32
1176 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1177 {
1178 	DECODE_HEAD;
1179 
1180 	if (argp->minorversion >= 1)
1181 		return nfserr_notsupp;
1182 
1183 	READ_BUF(NFS4_VERIFIER_SIZE);
1184 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1185 
1186 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1187 	if (status)
1188 		return nfserr_bad_xdr;
1189 	READ_BUF(8);
1190 	setclientid->se_callback_prog = be32_to_cpup(p++);
1191 	setclientid->se_callback_netid_len = be32_to_cpup(p++);
1192 	READ_BUF(setclientid->se_callback_netid_len);
1193 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1194 	READ_BUF(4);
1195 	setclientid->se_callback_addr_len = be32_to_cpup(p++);
1196 
1197 	READ_BUF(setclientid->se_callback_addr_len);
1198 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1199 	READ_BUF(4);
1200 	setclientid->se_callback_ident = be32_to_cpup(p++);
1201 
1202 	DECODE_TAIL;
1203 }
1204 
1205 static __be32
1206 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1207 {
1208 	DECODE_HEAD;
1209 
1210 	if (argp->minorversion >= 1)
1211 		return nfserr_notsupp;
1212 
1213 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1214 	COPYMEM(&scd_c->sc_clientid, 8);
1215 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1216 
1217 	DECODE_TAIL;
1218 }
1219 
1220 /* Also used for NVERIFY */
1221 static __be32
1222 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1223 {
1224 	DECODE_HEAD;
1225 
1226 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1227 		goto out;
1228 
1229 	/* For convenience's sake, we compare raw xdr'd attributes in
1230 	 * nfsd4_proc_verify */
1231 
1232 	READ_BUF(4);
1233 	verify->ve_attrlen = be32_to_cpup(p++);
1234 	READ_BUF(verify->ve_attrlen);
1235 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1236 
1237 	DECODE_TAIL;
1238 }
1239 
1240 static __be32
1241 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1242 {
1243 	int avail;
1244 	int len;
1245 	DECODE_HEAD;
1246 
1247 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1248 	if (status)
1249 		return status;
1250 	READ_BUF(16);
1251 	p = xdr_decode_hyper(p, &write->wr_offset);
1252 	write->wr_stable_how = be32_to_cpup(p++);
1253 	if (write->wr_stable_how > NFS_FILE_SYNC)
1254 		goto xdr_error;
1255 	write->wr_buflen = be32_to_cpup(p++);
1256 
1257 	/* Sorry .. no magic macros for this.. *
1258 	 * READ_BUF(write->wr_buflen);
1259 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1260 	 */
1261 	avail = (char*)argp->end - (char*)argp->p;
1262 	if (avail + argp->pagelen < write->wr_buflen) {
1263 		dprintk("NFSD: xdr error (%s:%d)\n",
1264 				__FILE__, __LINE__);
1265 		goto xdr_error;
1266 	}
1267 	write->wr_head.iov_base = p;
1268 	write->wr_head.iov_len = avail;
1269 	write->wr_pagelist = argp->pagelist;
1270 
1271 	len = XDR_QUADLEN(write->wr_buflen) << 2;
1272 	if (len >= avail) {
1273 		int pages;
1274 
1275 		len -= avail;
1276 
1277 		pages = len >> PAGE_SHIFT;
1278 		argp->pagelist += pages;
1279 		argp->pagelen -= pages * PAGE_SIZE;
1280 		len -= pages * PAGE_SIZE;
1281 
1282 		argp->p = (__be32 *)page_address(argp->pagelist[0]);
1283 		argp->pagelist++;
1284 		argp->end = argp->p + XDR_QUADLEN(PAGE_SIZE);
1285 	}
1286 	argp->p += XDR_QUADLEN(len);
1287 
1288 	DECODE_TAIL;
1289 }
1290 
1291 static __be32
1292 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1293 {
1294 	DECODE_HEAD;
1295 
1296 	if (argp->minorversion >= 1)
1297 		return nfserr_notsupp;
1298 
1299 	READ_BUF(12);
1300 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1301 	rlockowner->rl_owner.len = be32_to_cpup(p++);
1302 	READ_BUF(rlockowner->rl_owner.len);
1303 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1304 
1305 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1306 		return nfserr_inval;
1307 	DECODE_TAIL;
1308 }
1309 
1310 static __be32
1311 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1312 			 struct nfsd4_exchange_id *exid)
1313 {
1314 	int dummy, tmp;
1315 	DECODE_HEAD;
1316 
1317 	READ_BUF(NFS4_VERIFIER_SIZE);
1318 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1319 
1320 	status = nfsd4_decode_opaque(argp, &exid->clname);
1321 	if (status)
1322 		return nfserr_bad_xdr;
1323 
1324 	READ_BUF(4);
1325 	exid->flags = be32_to_cpup(p++);
1326 
1327 	/* Ignore state_protect4_a */
1328 	READ_BUF(4);
1329 	exid->spa_how = be32_to_cpup(p++);
1330 	switch (exid->spa_how) {
1331 	case SP4_NONE:
1332 		break;
1333 	case SP4_MACH_CRED:
1334 		/* spo_must_enforce */
1335 		status = nfsd4_decode_bitmap(argp,
1336 					exid->spo_must_enforce);
1337 		if (status)
1338 			goto out;
1339 		/* spo_must_allow */
1340 		status = nfsd4_decode_bitmap(argp, exid->spo_must_allow);
1341 		if (status)
1342 			goto out;
1343 		break;
1344 	case SP4_SSV:
1345 		/* ssp_ops */
1346 		READ_BUF(4);
1347 		dummy = be32_to_cpup(p++);
1348 		READ_BUF(dummy * 4);
1349 		p += dummy;
1350 
1351 		READ_BUF(4);
1352 		dummy = be32_to_cpup(p++);
1353 		READ_BUF(dummy * 4);
1354 		p += dummy;
1355 
1356 		/* ssp_hash_algs<> */
1357 		READ_BUF(4);
1358 		tmp = be32_to_cpup(p++);
1359 		while (tmp--) {
1360 			READ_BUF(4);
1361 			dummy = be32_to_cpup(p++);
1362 			READ_BUF(dummy);
1363 			p += XDR_QUADLEN(dummy);
1364 		}
1365 
1366 		/* ssp_encr_algs<> */
1367 		READ_BUF(4);
1368 		tmp = be32_to_cpup(p++);
1369 		while (tmp--) {
1370 			READ_BUF(4);
1371 			dummy = be32_to_cpup(p++);
1372 			READ_BUF(dummy);
1373 			p += XDR_QUADLEN(dummy);
1374 		}
1375 
1376 		/* ssp_window and ssp_num_gss_handles */
1377 		READ_BUF(8);
1378 		dummy = be32_to_cpup(p++);
1379 		dummy = be32_to_cpup(p++);
1380 		break;
1381 	default:
1382 		goto xdr_error;
1383 	}
1384 
1385 	/* Ignore Implementation ID */
1386 	READ_BUF(4);    /* nfs_impl_id4 array length */
1387 	dummy = be32_to_cpup(p++);
1388 
1389 	if (dummy > 1)
1390 		goto xdr_error;
1391 
1392 	if (dummy == 1) {
1393 		/* nii_domain */
1394 		READ_BUF(4);
1395 		dummy = be32_to_cpup(p++);
1396 		READ_BUF(dummy);
1397 		p += XDR_QUADLEN(dummy);
1398 
1399 		/* nii_name */
1400 		READ_BUF(4);
1401 		dummy = be32_to_cpup(p++);
1402 		READ_BUF(dummy);
1403 		p += XDR_QUADLEN(dummy);
1404 
1405 		/* nii_date */
1406 		READ_BUF(12);
1407 		p += 3;
1408 	}
1409 	DECODE_TAIL;
1410 }
1411 
1412 static __be32
1413 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1414 			    struct nfsd4_create_session *sess)
1415 {
1416 	DECODE_HEAD;
1417 	u32 dummy;
1418 
1419 	READ_BUF(16);
1420 	COPYMEM(&sess->clientid, 8);
1421 	sess->seqid = be32_to_cpup(p++);
1422 	sess->flags = be32_to_cpup(p++);
1423 
1424 	/* Fore channel attrs */
1425 	READ_BUF(28);
1426 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1427 	sess->fore_channel.maxreq_sz = be32_to_cpup(p++);
1428 	sess->fore_channel.maxresp_sz = be32_to_cpup(p++);
1429 	sess->fore_channel.maxresp_cached = be32_to_cpup(p++);
1430 	sess->fore_channel.maxops = be32_to_cpup(p++);
1431 	sess->fore_channel.maxreqs = be32_to_cpup(p++);
1432 	sess->fore_channel.nr_rdma_attrs = be32_to_cpup(p++);
1433 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1434 		READ_BUF(4);
1435 		sess->fore_channel.rdma_attrs = be32_to_cpup(p++);
1436 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1437 		dprintk("Too many fore channel attr bitmaps!\n");
1438 		goto xdr_error;
1439 	}
1440 
1441 	/* Back channel attrs */
1442 	READ_BUF(28);
1443 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1444 	sess->back_channel.maxreq_sz = be32_to_cpup(p++);
1445 	sess->back_channel.maxresp_sz = be32_to_cpup(p++);
1446 	sess->back_channel.maxresp_cached = be32_to_cpup(p++);
1447 	sess->back_channel.maxops = be32_to_cpup(p++);
1448 	sess->back_channel.maxreqs = be32_to_cpup(p++);
1449 	sess->back_channel.nr_rdma_attrs = be32_to_cpup(p++);
1450 	if (sess->back_channel.nr_rdma_attrs == 1) {
1451 		READ_BUF(4);
1452 		sess->back_channel.rdma_attrs = be32_to_cpup(p++);
1453 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1454 		dprintk("Too many back channel attr bitmaps!\n");
1455 		goto xdr_error;
1456 	}
1457 
1458 	READ_BUF(4);
1459 	sess->callback_prog = be32_to_cpup(p++);
1460 	nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1461 	DECODE_TAIL;
1462 }
1463 
1464 static __be32
1465 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1466 			     struct nfsd4_destroy_session *destroy_session)
1467 {
1468 	DECODE_HEAD;
1469 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1470 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1471 
1472 	DECODE_TAIL;
1473 }
1474 
1475 static __be32
1476 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1477 			  struct nfsd4_free_stateid *free_stateid)
1478 {
1479 	DECODE_HEAD;
1480 
1481 	READ_BUF(sizeof(stateid_t));
1482 	free_stateid->fr_stateid.si_generation = be32_to_cpup(p++);
1483 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1484 
1485 	DECODE_TAIL;
1486 }
1487 
1488 static __be32
1489 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1490 		      struct nfsd4_sequence *seq)
1491 {
1492 	DECODE_HEAD;
1493 
1494 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1495 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1496 	seq->seqid = be32_to_cpup(p++);
1497 	seq->slotid = be32_to_cpup(p++);
1498 	seq->maxslots = be32_to_cpup(p++);
1499 	seq->cachethis = be32_to_cpup(p++);
1500 
1501 	DECODE_TAIL;
1502 }
1503 
1504 static __be32
1505 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1506 {
1507 	int i;
1508 	__be32 *p, status;
1509 	struct nfsd4_test_stateid_id *stateid;
1510 
1511 	READ_BUF(4);
1512 	test_stateid->ts_num_ids = ntohl(*p++);
1513 
1514 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1515 
1516 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1517 		stateid = svcxdr_tmpalloc(argp, sizeof(*stateid));
1518 		if (!stateid) {
1519 			status = nfserrno(-ENOMEM);
1520 			goto out;
1521 		}
1522 
1523 		INIT_LIST_HEAD(&stateid->ts_id_list);
1524 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1525 
1526 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1527 		if (status)
1528 			goto out;
1529 	}
1530 
1531 	status = 0;
1532 out:
1533 	return status;
1534 xdr_error:
1535 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1536 	status = nfserr_bad_xdr;
1537 	goto out;
1538 }
1539 
1540 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1541 {
1542 	DECODE_HEAD;
1543 
1544 	READ_BUF(8);
1545 	COPYMEM(&dc->clientid, 8);
1546 
1547 	DECODE_TAIL;
1548 }
1549 
1550 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1551 {
1552 	DECODE_HEAD;
1553 
1554 	READ_BUF(4);
1555 	rc->rca_one_fs = be32_to_cpup(p++);
1556 
1557 	DECODE_TAIL;
1558 }
1559 
1560 #ifdef CONFIG_NFSD_PNFS
1561 static __be32
1562 nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp,
1563 		struct nfsd4_getdeviceinfo *gdev)
1564 {
1565 	DECODE_HEAD;
1566 	u32 num, i;
1567 
1568 	READ_BUF(sizeof(struct nfsd4_deviceid) + 3 * 4);
1569 	COPYMEM(&gdev->gd_devid, sizeof(struct nfsd4_deviceid));
1570 	gdev->gd_layout_type = be32_to_cpup(p++);
1571 	gdev->gd_maxcount = be32_to_cpup(p++);
1572 	num = be32_to_cpup(p++);
1573 	if (num) {
1574 		READ_BUF(4 * num);
1575 		gdev->gd_notify_types = be32_to_cpup(p++);
1576 		for (i = 1; i < num; i++) {
1577 			if (be32_to_cpup(p++)) {
1578 				status = nfserr_inval;
1579 				goto out;
1580 			}
1581 		}
1582 	}
1583 	DECODE_TAIL;
1584 }
1585 
1586 static __be32
1587 nfsd4_decode_layoutget(struct nfsd4_compoundargs *argp,
1588 		struct nfsd4_layoutget *lgp)
1589 {
1590 	DECODE_HEAD;
1591 
1592 	READ_BUF(36);
1593 	lgp->lg_signal = be32_to_cpup(p++);
1594 	lgp->lg_layout_type = be32_to_cpup(p++);
1595 	lgp->lg_seg.iomode = be32_to_cpup(p++);
1596 	p = xdr_decode_hyper(p, &lgp->lg_seg.offset);
1597 	p = xdr_decode_hyper(p, &lgp->lg_seg.length);
1598 	p = xdr_decode_hyper(p, &lgp->lg_minlength);
1599 
1600 	status = nfsd4_decode_stateid(argp, &lgp->lg_sid);
1601 	if (status)
1602 		return status;
1603 
1604 	READ_BUF(4);
1605 	lgp->lg_maxcount = be32_to_cpup(p++);
1606 
1607 	DECODE_TAIL;
1608 }
1609 
1610 static __be32
1611 nfsd4_decode_layoutcommit(struct nfsd4_compoundargs *argp,
1612 		struct nfsd4_layoutcommit *lcp)
1613 {
1614 	DECODE_HEAD;
1615 	u32 timechange;
1616 
1617 	READ_BUF(20);
1618 	p = xdr_decode_hyper(p, &lcp->lc_seg.offset);
1619 	p = xdr_decode_hyper(p, &lcp->lc_seg.length);
1620 	lcp->lc_reclaim = be32_to_cpup(p++);
1621 
1622 	status = nfsd4_decode_stateid(argp, &lcp->lc_sid);
1623 	if (status)
1624 		return status;
1625 
1626 	READ_BUF(4);
1627 	lcp->lc_newoffset = be32_to_cpup(p++);
1628 	if (lcp->lc_newoffset) {
1629 		READ_BUF(8);
1630 		p = xdr_decode_hyper(p, &lcp->lc_last_wr);
1631 	} else
1632 		lcp->lc_last_wr = 0;
1633 	READ_BUF(4);
1634 	timechange = be32_to_cpup(p++);
1635 	if (timechange) {
1636 		status = nfsd4_decode_time(argp, &lcp->lc_mtime);
1637 		if (status)
1638 			return status;
1639 	} else {
1640 		lcp->lc_mtime.tv_nsec = UTIME_NOW;
1641 	}
1642 	READ_BUF(8);
1643 	lcp->lc_layout_type = be32_to_cpup(p++);
1644 
1645 	/*
1646 	 * Save the layout update in XDR format and let the layout driver deal
1647 	 * with it later.
1648 	 */
1649 	lcp->lc_up_len = be32_to_cpup(p++);
1650 	if (lcp->lc_up_len > 0) {
1651 		READ_BUF(lcp->lc_up_len);
1652 		READMEM(lcp->lc_up_layout, lcp->lc_up_len);
1653 	}
1654 
1655 	DECODE_TAIL;
1656 }
1657 
1658 static __be32
1659 nfsd4_decode_layoutreturn(struct nfsd4_compoundargs *argp,
1660 		struct nfsd4_layoutreturn *lrp)
1661 {
1662 	DECODE_HEAD;
1663 
1664 	READ_BUF(16);
1665 	lrp->lr_reclaim = be32_to_cpup(p++);
1666 	lrp->lr_layout_type = be32_to_cpup(p++);
1667 	lrp->lr_seg.iomode = be32_to_cpup(p++);
1668 	lrp->lr_return_type = be32_to_cpup(p++);
1669 	if (lrp->lr_return_type == RETURN_FILE) {
1670 		READ_BUF(16);
1671 		p = xdr_decode_hyper(p, &lrp->lr_seg.offset);
1672 		p = xdr_decode_hyper(p, &lrp->lr_seg.length);
1673 
1674 		status = nfsd4_decode_stateid(argp, &lrp->lr_sid);
1675 		if (status)
1676 			return status;
1677 
1678 		READ_BUF(4);
1679 		lrp->lrf_body_len = be32_to_cpup(p++);
1680 		if (lrp->lrf_body_len > 0) {
1681 			READ_BUF(lrp->lrf_body_len);
1682 			READMEM(lrp->lrf_body, lrp->lrf_body_len);
1683 		}
1684 	} else {
1685 		lrp->lr_seg.offset = 0;
1686 		lrp->lr_seg.length = NFS4_MAX_UINT64;
1687 	}
1688 
1689 	DECODE_TAIL;
1690 }
1691 #endif /* CONFIG_NFSD_PNFS */
1692 
1693 static __be32
1694 nfsd4_decode_fallocate(struct nfsd4_compoundargs *argp,
1695 		       struct nfsd4_fallocate *fallocate)
1696 {
1697 	DECODE_HEAD;
1698 
1699 	status = nfsd4_decode_stateid(argp, &fallocate->falloc_stateid);
1700 	if (status)
1701 		return status;
1702 
1703 	READ_BUF(16);
1704 	p = xdr_decode_hyper(p, &fallocate->falloc_offset);
1705 	xdr_decode_hyper(p, &fallocate->falloc_length);
1706 
1707 	DECODE_TAIL;
1708 }
1709 
1710 static __be32
1711 nfsd4_decode_clone(struct nfsd4_compoundargs *argp, struct nfsd4_clone *clone)
1712 {
1713 	DECODE_HEAD;
1714 
1715 	status = nfsd4_decode_stateid(argp, &clone->cl_src_stateid);
1716 	if (status)
1717 		return status;
1718 	status = nfsd4_decode_stateid(argp, &clone->cl_dst_stateid);
1719 	if (status)
1720 		return status;
1721 
1722 	READ_BUF(8 + 8 + 8);
1723 	p = xdr_decode_hyper(p, &clone->cl_src_pos);
1724 	p = xdr_decode_hyper(p, &clone->cl_dst_pos);
1725 	p = xdr_decode_hyper(p, &clone->cl_count);
1726 	DECODE_TAIL;
1727 }
1728 
1729 static __be32
1730 nfsd4_decode_copy(struct nfsd4_compoundargs *argp, struct nfsd4_copy *copy)
1731 {
1732 	DECODE_HEAD;
1733 	unsigned int tmp;
1734 
1735 	status = nfsd4_decode_stateid(argp, &copy->cp_src_stateid);
1736 	if (status)
1737 		return status;
1738 	status = nfsd4_decode_stateid(argp, &copy->cp_dst_stateid);
1739 	if (status)
1740 		return status;
1741 
1742 	READ_BUF(8 + 8 + 8 + 4 + 4 + 4);
1743 	p = xdr_decode_hyper(p, &copy->cp_src_pos);
1744 	p = xdr_decode_hyper(p, &copy->cp_dst_pos);
1745 	p = xdr_decode_hyper(p, &copy->cp_count);
1746 	copy->cp_consecutive = be32_to_cpup(p++);
1747 	copy->cp_synchronous = be32_to_cpup(p++);
1748 	tmp = be32_to_cpup(p); /* Source server list not supported */
1749 
1750 	DECODE_TAIL;
1751 }
1752 
1753 static __be32
1754 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
1755 {
1756 	DECODE_HEAD;
1757 
1758 	status = nfsd4_decode_stateid(argp, &seek->seek_stateid);
1759 	if (status)
1760 		return status;
1761 
1762 	READ_BUF(8 + 4);
1763 	p = xdr_decode_hyper(p, &seek->seek_offset);
1764 	seek->seek_whence = be32_to_cpup(p);
1765 
1766 	DECODE_TAIL;
1767 }
1768 
1769 static __be32
1770 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1771 {
1772 	return nfs_ok;
1773 }
1774 
1775 static __be32
1776 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1777 {
1778 	return nfserr_notsupp;
1779 }
1780 
1781 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1782 
1783 static nfsd4_dec nfsd4_dec_ops[] = {
1784 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1785 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1786 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1787 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1788 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1789 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1790 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1791 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1792 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1793 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1794 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1795 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1796 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1797 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1798 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1799 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1800 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1801 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1802 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1803 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1804 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_putpubfh,
1805 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1806 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1807 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1808 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1809 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1810 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1811 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1812 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1813 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1814 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1815 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1816 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1817 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1818 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1819 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1820 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1821 
1822 	/* new operations for NFSv4.1 */
1823 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_backchannel_ctl,
1824 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1825 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1826 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1827 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1828 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
1829 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1830 #ifdef CONFIG_NFSD_PNFS
1831 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_getdeviceinfo,
1832 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1833 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_layoutcommit,
1834 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_layoutget,
1835 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_layoutreturn,
1836 #else
1837 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1838 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1839 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1840 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1841 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1842 #endif
1843 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1844 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1845 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1846 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
1847 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1848 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
1849 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1850 
1851 	/* new operations for NFSv4.2 */
1852 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1853 	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_copy,
1854 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
1855 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1856 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1857 	[OP_LAYOUTERROR]	= (nfsd4_dec)nfsd4_decode_notsupp,
1858 	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1859 	[OP_OFFLOAD_CANCEL]	= (nfsd4_dec)nfsd4_decode_notsupp,
1860 	[OP_OFFLOAD_STATUS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1861 	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_notsupp,
1862 	[OP_SEEK]		= (nfsd4_dec)nfsd4_decode_seek,
1863 	[OP_WRITE_SAME]		= (nfsd4_dec)nfsd4_decode_notsupp,
1864 	[OP_CLONE]		= (nfsd4_dec)nfsd4_decode_clone,
1865 };
1866 
1867 static inline bool
1868 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
1869 {
1870 	if (op->opnum < FIRST_NFS4_OP)
1871 		return false;
1872 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
1873 		return false;
1874 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
1875 		return false;
1876 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
1877 		return false;
1878 	return true;
1879 }
1880 
1881 static __be32
1882 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1883 {
1884 	DECODE_HEAD;
1885 	struct nfsd4_op *op;
1886 	bool cachethis = false;
1887 	int auth_slack= argp->rqstp->rq_auth_slack;
1888 	int max_reply = auth_slack + 8; /* opcnt, status */
1889 	int readcount = 0;
1890 	int readbytes = 0;
1891 	int i;
1892 
1893 	READ_BUF(4);
1894 	argp->taglen = be32_to_cpup(p++);
1895 	READ_BUF(argp->taglen);
1896 	SAVEMEM(argp->tag, argp->taglen);
1897 	READ_BUF(8);
1898 	argp->minorversion = be32_to_cpup(p++);
1899 	argp->opcnt = be32_to_cpup(p++);
1900 	max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
1901 
1902 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1903 		goto xdr_error;
1904 	if (argp->opcnt > 100)
1905 		goto xdr_error;
1906 
1907 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1908 		argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1909 		if (!argp->ops) {
1910 			argp->ops = argp->iops;
1911 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1912 			goto xdr_error;
1913 		}
1914 	}
1915 
1916 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
1917 		argp->opcnt = 0;
1918 
1919 	for (i = 0; i < argp->opcnt; i++) {
1920 		op = &argp->ops[i];
1921 		op->replay = NULL;
1922 
1923 		READ_BUF(4);
1924 		op->opnum = be32_to_cpup(p++);
1925 
1926 		if (nfsd4_opnum_in_range(argp, op))
1927 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
1928 		else {
1929 			op->opnum = OP_ILLEGAL;
1930 			op->status = nfserr_op_illegal;
1931 		}
1932 		/*
1933 		 * We'll try to cache the result in the DRC if any one
1934 		 * op in the compound wants to be cached:
1935 		 */
1936 		cachethis |= nfsd4_cache_this_op(op);
1937 
1938 		if (op->opnum == OP_READ) {
1939 			readcount++;
1940 			readbytes += nfsd4_max_reply(argp->rqstp, op);
1941 		} else
1942 			max_reply += nfsd4_max_reply(argp->rqstp, op);
1943 		/*
1944 		 * OP_LOCK and OP_LOCKT may return a conflicting lock.
1945 		 * (Special case because it will just skip encoding this
1946 		 * if it runs out of xdr buffer space, and it is the only
1947 		 * operation that behaves this way.)
1948 		 */
1949 		if (op->opnum == OP_LOCK || op->opnum == OP_LOCKT)
1950 			max_reply += NFS4_OPAQUE_LIMIT;
1951 
1952 		if (op->status) {
1953 			argp->opcnt = i+1;
1954 			break;
1955 		}
1956 	}
1957 	/* Sessions make the DRC unnecessary: */
1958 	if (argp->minorversion)
1959 		cachethis = false;
1960 	svc_reserve(argp->rqstp, max_reply + readbytes);
1961 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1962 
1963 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
1964 		clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
1965 
1966 	DECODE_TAIL;
1967 }
1968 
1969 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode,
1970 			     struct svc_export *exp)
1971 {
1972 	if (exp->ex_flags & NFSEXP_V4ROOT) {
1973 		*p++ = cpu_to_be32(convert_to_wallclock(exp->cd->flush_time));
1974 		*p++ = 0;
1975 	} else if (IS_I_VERSION(inode)) {
1976 		p = xdr_encode_hyper(p, inode->i_version);
1977 	} else {
1978 		*p++ = cpu_to_be32(stat->ctime.tv_sec);
1979 		*p++ = cpu_to_be32(stat->ctime.tv_nsec);
1980 	}
1981 	return p;
1982 }
1983 
1984 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
1985 {
1986 	*p++ = cpu_to_be32(c->atomic);
1987 	if (c->change_supported) {
1988 		p = xdr_encode_hyper(p, c->before_change);
1989 		p = xdr_encode_hyper(p, c->after_change);
1990 	} else {
1991 		*p++ = cpu_to_be32(c->before_ctime_sec);
1992 		*p++ = cpu_to_be32(c->before_ctime_nsec);
1993 		*p++ = cpu_to_be32(c->after_ctime_sec);
1994 		*p++ = cpu_to_be32(c->after_ctime_nsec);
1995 	}
1996 	return p;
1997 }
1998 
1999 /* Encode as an array of strings the string given with components
2000  * separated @sep, escaped with esc_enter and esc_exit.
2001  */
2002 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
2003 					  char *components, char esc_enter,
2004 					  char esc_exit)
2005 {
2006 	__be32 *p;
2007 	__be32 pathlen;
2008 	int pathlen_offset;
2009 	int strlen, count=0;
2010 	char *str, *end, *next;
2011 
2012 	dprintk("nfsd4_encode_components(%s)\n", components);
2013 
2014 	pathlen_offset = xdr->buf->len;
2015 	p = xdr_reserve_space(xdr, 4);
2016 	if (!p)
2017 		return nfserr_resource;
2018 	p++; /* We will fill this in with @count later */
2019 
2020 	end = str = components;
2021 	while (*end) {
2022 		bool found_esc = false;
2023 
2024 		/* try to parse as esc_start, ..., esc_end, sep */
2025 		if (*str == esc_enter) {
2026 			for (; *end && (*end != esc_exit); end++)
2027 				/* find esc_exit or end of string */;
2028 			next = end + 1;
2029 			if (*end && (!*next || *next == sep)) {
2030 				str++;
2031 				found_esc = true;
2032 			}
2033 		}
2034 
2035 		if (!found_esc)
2036 			for (; *end && (*end != sep); end++)
2037 				/* find sep or end of string */;
2038 
2039 		strlen = end - str;
2040 		if (strlen) {
2041 			p = xdr_reserve_space(xdr, strlen + 4);
2042 			if (!p)
2043 				return nfserr_resource;
2044 			p = xdr_encode_opaque(p, str, strlen);
2045 			count++;
2046 		}
2047 		else
2048 			end++;
2049 		if (found_esc)
2050 			end = next;
2051 
2052 		str = end;
2053 	}
2054 	pathlen = htonl(count);
2055 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
2056 	return 0;
2057 }
2058 
2059 /* Encode as an array of strings the string given with components
2060  * separated @sep.
2061  */
2062 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
2063 				      char *components)
2064 {
2065 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
2066 }
2067 
2068 /*
2069  * encode a location element of a fs_locations structure
2070  */
2071 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
2072 					struct nfsd4_fs_location *location)
2073 {
2074 	__be32 status;
2075 
2076 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
2077 						'[', ']');
2078 	if (status)
2079 		return status;
2080 	status = nfsd4_encode_components(xdr, '/', location->path);
2081 	if (status)
2082 		return status;
2083 	return 0;
2084 }
2085 
2086 /*
2087  * Encode a path in RFC3530 'pathname4' format
2088  */
2089 static __be32 nfsd4_encode_path(struct xdr_stream *xdr,
2090 				const struct path *root,
2091 				const struct path *path)
2092 {
2093 	struct path cur = *path;
2094 	__be32 *p;
2095 	struct dentry **components = NULL;
2096 	unsigned int ncomponents = 0;
2097 	__be32 err = nfserr_jukebox;
2098 
2099 	dprintk("nfsd4_encode_components(");
2100 
2101 	path_get(&cur);
2102 	/* First walk the path up to the nfsd root, and store the
2103 	 * dentries/path components in an array.
2104 	 */
2105 	for (;;) {
2106 		if (path_equal(&cur, root))
2107 			break;
2108 		if (cur.dentry == cur.mnt->mnt_root) {
2109 			if (follow_up(&cur))
2110 				continue;
2111 			goto out_free;
2112 		}
2113 		if ((ncomponents & 15) == 0) {
2114 			struct dentry **new;
2115 			new = krealloc(components,
2116 					sizeof(*new) * (ncomponents + 16),
2117 					GFP_KERNEL);
2118 			if (!new)
2119 				goto out_free;
2120 			components = new;
2121 		}
2122 		components[ncomponents++] = cur.dentry;
2123 		cur.dentry = dget_parent(cur.dentry);
2124 	}
2125 	err = nfserr_resource;
2126 	p = xdr_reserve_space(xdr, 4);
2127 	if (!p)
2128 		goto out_free;
2129 	*p++ = cpu_to_be32(ncomponents);
2130 
2131 	while (ncomponents) {
2132 		struct dentry *dentry = components[ncomponents - 1];
2133 		unsigned int len;
2134 
2135 		spin_lock(&dentry->d_lock);
2136 		len = dentry->d_name.len;
2137 		p = xdr_reserve_space(xdr, len + 4);
2138 		if (!p) {
2139 			spin_unlock(&dentry->d_lock);
2140 			goto out_free;
2141 		}
2142 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
2143 		dprintk("/%pd", dentry);
2144 		spin_unlock(&dentry->d_lock);
2145 		dput(dentry);
2146 		ncomponents--;
2147 	}
2148 
2149 	err = 0;
2150 out_free:
2151 	dprintk(")\n");
2152 	while (ncomponents)
2153 		dput(components[--ncomponents]);
2154 	kfree(components);
2155 	path_put(&cur);
2156 	return err;
2157 }
2158 
2159 static __be32 nfsd4_encode_fsloc_fsroot(struct xdr_stream *xdr,
2160 			struct svc_rqst *rqstp, const struct path *path)
2161 {
2162 	struct svc_export *exp_ps;
2163 	__be32 res;
2164 
2165 	exp_ps = rqst_find_fsidzero_export(rqstp);
2166 	if (IS_ERR(exp_ps))
2167 		return nfserrno(PTR_ERR(exp_ps));
2168 	res = nfsd4_encode_path(xdr, &exp_ps->ex_path, path);
2169 	exp_put(exp_ps);
2170 	return res;
2171 }
2172 
2173 /*
2174  *  encode a fs_locations structure
2175  */
2176 static __be32 nfsd4_encode_fs_locations(struct xdr_stream *xdr,
2177 			struct svc_rqst *rqstp, struct svc_export *exp)
2178 {
2179 	__be32 status;
2180 	int i;
2181 	__be32 *p;
2182 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
2183 
2184 	status = nfsd4_encode_fsloc_fsroot(xdr, rqstp, &exp->ex_path);
2185 	if (status)
2186 		return status;
2187 	p = xdr_reserve_space(xdr, 4);
2188 	if (!p)
2189 		return nfserr_resource;
2190 	*p++ = cpu_to_be32(fslocs->locations_count);
2191 	for (i=0; i<fslocs->locations_count; i++) {
2192 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
2193 		if (status)
2194 			return status;
2195 	}
2196 	return 0;
2197 }
2198 
2199 static u32 nfs4_file_type(umode_t mode)
2200 {
2201 	switch (mode & S_IFMT) {
2202 	case S_IFIFO:	return NF4FIFO;
2203 	case S_IFCHR:	return NF4CHR;
2204 	case S_IFDIR:	return NF4DIR;
2205 	case S_IFBLK:	return NF4BLK;
2206 	case S_IFLNK:	return NF4LNK;
2207 	case S_IFREG:	return NF4REG;
2208 	case S_IFSOCK:	return NF4SOCK;
2209 	default:	return NF4BAD;
2210 	};
2211 }
2212 
2213 static inline __be32
2214 nfsd4_encode_aclname(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2215 		     struct nfs4_ace *ace)
2216 {
2217 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
2218 		return nfs4_acl_write_who(xdr, ace->whotype);
2219 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
2220 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
2221 	else
2222 		return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
2223 }
2224 
2225 static inline __be32
2226 nfsd4_encode_layout_types(struct xdr_stream *xdr, u32 layout_types)
2227 {
2228 	__be32		*p;
2229 	unsigned long	i = hweight_long(layout_types);
2230 
2231 	p = xdr_reserve_space(xdr, 4 + 4 * i);
2232 	if (!p)
2233 		return nfserr_resource;
2234 
2235 	*p++ = cpu_to_be32(i);
2236 
2237 	for (i = LAYOUT_NFSV4_1_FILES; i < LAYOUT_TYPE_MAX; ++i)
2238 		if (layout_types & (1 << i))
2239 			*p++ = cpu_to_be32(i);
2240 
2241 	return 0;
2242 }
2243 
2244 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
2245 			      FATTR4_WORD0_RDATTR_ERROR)
2246 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2247 #define WORD2_ABSENT_FS_ATTRS 0
2248 
2249 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2250 static inline __be32
2251 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2252 			    void *context, int len)
2253 {
2254 	__be32 *p;
2255 
2256 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2257 	if (!p)
2258 		return nfserr_resource;
2259 
2260 	/*
2261 	 * For now we use a 0 here to indicate the null translation; in
2262 	 * the future we may place a call to translation code here.
2263 	 */
2264 	*p++ = cpu_to_be32(0); /* lfs */
2265 	*p++ = cpu_to_be32(0); /* pi */
2266 	p = xdr_encode_opaque(p, context, len);
2267 	return 0;
2268 }
2269 #else
2270 static inline __be32
2271 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2272 			    void *context, int len)
2273 { return 0; }
2274 #endif
2275 
2276 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *bmval2, u32 *rdattr_err)
2277 {
2278 	/* As per referral draft:  */
2279 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2280 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2281 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2282 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2283 			*rdattr_err = NFSERR_MOVED;
2284 		else
2285 			return nfserr_moved;
2286 	}
2287 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2288 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2289 	*bmval2 &= WORD2_ABSENT_FS_ATTRS;
2290 	return 0;
2291 }
2292 
2293 
2294 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2295 {
2296 	struct path path = exp->ex_path;
2297 	int err;
2298 
2299 	path_get(&path);
2300 	while (follow_up(&path)) {
2301 		if (path.dentry != path.mnt->mnt_root)
2302 			break;
2303 	}
2304 	err = vfs_getattr(&path, stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
2305 	path_put(&path);
2306 	return err;
2307 }
2308 
2309 static __be32
2310 nfsd4_encode_bitmap(struct xdr_stream *xdr, u32 bmval0, u32 bmval1, u32 bmval2)
2311 {
2312 	__be32 *p;
2313 
2314 	if (bmval2) {
2315 		p = xdr_reserve_space(xdr, 16);
2316 		if (!p)
2317 			goto out_resource;
2318 		*p++ = cpu_to_be32(3);
2319 		*p++ = cpu_to_be32(bmval0);
2320 		*p++ = cpu_to_be32(bmval1);
2321 		*p++ = cpu_to_be32(bmval2);
2322 	} else if (bmval1) {
2323 		p = xdr_reserve_space(xdr, 12);
2324 		if (!p)
2325 			goto out_resource;
2326 		*p++ = cpu_to_be32(2);
2327 		*p++ = cpu_to_be32(bmval0);
2328 		*p++ = cpu_to_be32(bmval1);
2329 	} else {
2330 		p = xdr_reserve_space(xdr, 8);
2331 		if (!p)
2332 			goto out_resource;
2333 		*p++ = cpu_to_be32(1);
2334 		*p++ = cpu_to_be32(bmval0);
2335 	}
2336 
2337 	return 0;
2338 out_resource:
2339 	return nfserr_resource;
2340 }
2341 
2342 /*
2343  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2344  * ourselves.
2345  */
2346 static __be32
2347 nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
2348 		struct svc_export *exp,
2349 		struct dentry *dentry, u32 *bmval,
2350 		struct svc_rqst *rqstp, int ignore_crossmnt)
2351 {
2352 	u32 bmval0 = bmval[0];
2353 	u32 bmval1 = bmval[1];
2354 	u32 bmval2 = bmval[2];
2355 	struct kstat stat;
2356 	struct svc_fh *tempfh = NULL;
2357 	struct kstatfs statfs;
2358 	__be32 *p;
2359 	int starting_len = xdr->buf->len;
2360 	int attrlen_offset;
2361 	__be32 attrlen;
2362 	u32 dummy;
2363 	u64 dummy64;
2364 	u32 rdattr_err = 0;
2365 	__be32 status;
2366 	int err;
2367 	struct nfs4_acl *acl = NULL;
2368 	void *context = NULL;
2369 	int contextlen;
2370 	bool contextsupport = false;
2371 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2372 	u32 minorversion = resp->cstate.minorversion;
2373 	struct path path = {
2374 		.mnt	= exp->ex_path.mnt,
2375 		.dentry	= dentry,
2376 	};
2377 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2378 
2379 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2380 	BUG_ON(!nfsd_attrs_supported(minorversion, bmval));
2381 
2382 	if (exp->ex_fslocs.migrated) {
2383 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &bmval2, &rdattr_err);
2384 		if (status)
2385 			goto out;
2386 	}
2387 
2388 	err = vfs_getattr(&path, &stat, STATX_BASIC_STATS, AT_STATX_SYNC_AS_STAT);
2389 	if (err)
2390 		goto out_nfserr;
2391 	if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
2392 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
2393 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2394 		       FATTR4_WORD1_SPACE_TOTAL))) {
2395 		err = vfs_statfs(&path, &statfs);
2396 		if (err)
2397 			goto out_nfserr;
2398 	}
2399 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2400 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2401 		status = nfserr_jukebox;
2402 		if (!tempfh)
2403 			goto out;
2404 		fh_init(tempfh, NFS4_FHSIZE);
2405 		status = fh_compose(tempfh, exp, dentry, NULL);
2406 		if (status)
2407 			goto out;
2408 		fhp = tempfh;
2409 	}
2410 	if (bmval0 & FATTR4_WORD0_ACL) {
2411 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2412 		if (err == -EOPNOTSUPP)
2413 			bmval0 &= ~FATTR4_WORD0_ACL;
2414 		else if (err == -EINVAL) {
2415 			status = nfserr_attrnotsupp;
2416 			goto out;
2417 		} else if (err != 0)
2418 			goto out_nfserr;
2419 	}
2420 
2421 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2422 	if ((bmval2 & FATTR4_WORD2_SECURITY_LABEL) ||
2423 	     bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2424 		if (exp->ex_flags & NFSEXP_SECURITY_LABEL)
2425 			err = security_inode_getsecctx(d_inode(dentry),
2426 						&context, &contextlen);
2427 		else
2428 			err = -EOPNOTSUPP;
2429 		contextsupport = (err == 0);
2430 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2431 			if (err == -EOPNOTSUPP)
2432 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2433 			else if (err)
2434 				goto out_nfserr;
2435 		}
2436 	}
2437 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2438 
2439 	status = nfsd4_encode_bitmap(xdr, bmval0, bmval1, bmval2);
2440 	if (status)
2441 		goto out;
2442 
2443 	attrlen_offset = xdr->buf->len;
2444 	p = xdr_reserve_space(xdr, 4);
2445 	if (!p)
2446 		goto out_resource;
2447 	p++;                /* to be backfilled later */
2448 
2449 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2450 		u32 supp[3];
2451 
2452 		memcpy(supp, nfsd_suppattrs[minorversion], sizeof(supp));
2453 
2454 		if (!IS_POSIXACL(dentry->d_inode))
2455 			supp[0] &= ~FATTR4_WORD0_ACL;
2456 		if (!contextsupport)
2457 			supp[2] &= ~FATTR4_WORD2_SECURITY_LABEL;
2458 		if (!supp[2]) {
2459 			p = xdr_reserve_space(xdr, 12);
2460 			if (!p)
2461 				goto out_resource;
2462 			*p++ = cpu_to_be32(2);
2463 			*p++ = cpu_to_be32(supp[0]);
2464 			*p++ = cpu_to_be32(supp[1]);
2465 		} else {
2466 			p = xdr_reserve_space(xdr, 16);
2467 			if (!p)
2468 				goto out_resource;
2469 			*p++ = cpu_to_be32(3);
2470 			*p++ = cpu_to_be32(supp[0]);
2471 			*p++ = cpu_to_be32(supp[1]);
2472 			*p++ = cpu_to_be32(supp[2]);
2473 		}
2474 	}
2475 	if (bmval0 & FATTR4_WORD0_TYPE) {
2476 		p = xdr_reserve_space(xdr, 4);
2477 		if (!p)
2478 			goto out_resource;
2479 		dummy = nfs4_file_type(stat.mode);
2480 		if (dummy == NF4BAD) {
2481 			status = nfserr_serverfault;
2482 			goto out;
2483 		}
2484 		*p++ = cpu_to_be32(dummy);
2485 	}
2486 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2487 		p = xdr_reserve_space(xdr, 4);
2488 		if (!p)
2489 			goto out_resource;
2490 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2491 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT);
2492 		else
2493 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT|
2494 						NFS4_FH_VOL_RENAME);
2495 	}
2496 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2497 		p = xdr_reserve_space(xdr, 8);
2498 		if (!p)
2499 			goto out_resource;
2500 		p = encode_change(p, &stat, d_inode(dentry), exp);
2501 	}
2502 	if (bmval0 & FATTR4_WORD0_SIZE) {
2503 		p = xdr_reserve_space(xdr, 8);
2504 		if (!p)
2505 			goto out_resource;
2506 		p = xdr_encode_hyper(p, stat.size);
2507 	}
2508 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2509 		p = xdr_reserve_space(xdr, 4);
2510 		if (!p)
2511 			goto out_resource;
2512 		*p++ = cpu_to_be32(1);
2513 	}
2514 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2515 		p = xdr_reserve_space(xdr, 4);
2516 		if (!p)
2517 			goto out_resource;
2518 		*p++ = cpu_to_be32(1);
2519 	}
2520 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2521 		p = xdr_reserve_space(xdr, 4);
2522 		if (!p)
2523 			goto out_resource;
2524 		*p++ = cpu_to_be32(0);
2525 	}
2526 	if (bmval0 & FATTR4_WORD0_FSID) {
2527 		p = xdr_reserve_space(xdr, 16);
2528 		if (!p)
2529 			goto out_resource;
2530 		if (exp->ex_fslocs.migrated) {
2531 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
2532 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
2533 		} else switch(fsid_source(fhp)) {
2534 		case FSIDSOURCE_FSID:
2535 			p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
2536 			p = xdr_encode_hyper(p, (u64)0);
2537 			break;
2538 		case FSIDSOURCE_DEV:
2539 			*p++ = cpu_to_be32(0);
2540 			*p++ = cpu_to_be32(MAJOR(stat.dev));
2541 			*p++ = cpu_to_be32(0);
2542 			*p++ = cpu_to_be32(MINOR(stat.dev));
2543 			break;
2544 		case FSIDSOURCE_UUID:
2545 			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
2546 								EX_UUID_LEN);
2547 			break;
2548 		}
2549 	}
2550 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2551 		p = xdr_reserve_space(xdr, 4);
2552 		if (!p)
2553 			goto out_resource;
2554 		*p++ = cpu_to_be32(0);
2555 	}
2556 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2557 		p = xdr_reserve_space(xdr, 4);
2558 		if (!p)
2559 			goto out_resource;
2560 		*p++ = cpu_to_be32(nn->nfsd4_lease);
2561 	}
2562 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2563 		p = xdr_reserve_space(xdr, 4);
2564 		if (!p)
2565 			goto out_resource;
2566 		*p++ = cpu_to_be32(rdattr_err);
2567 	}
2568 	if (bmval0 & FATTR4_WORD0_ACL) {
2569 		struct nfs4_ace *ace;
2570 
2571 		if (acl == NULL) {
2572 			p = xdr_reserve_space(xdr, 4);
2573 			if (!p)
2574 				goto out_resource;
2575 
2576 			*p++ = cpu_to_be32(0);
2577 			goto out_acl;
2578 		}
2579 		p = xdr_reserve_space(xdr, 4);
2580 		if (!p)
2581 			goto out_resource;
2582 		*p++ = cpu_to_be32(acl->naces);
2583 
2584 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2585 			p = xdr_reserve_space(xdr, 4*3);
2586 			if (!p)
2587 				goto out_resource;
2588 			*p++ = cpu_to_be32(ace->type);
2589 			*p++ = cpu_to_be32(ace->flag);
2590 			*p++ = cpu_to_be32(ace->access_mask &
2591 							NFS4_ACE_MASK_ALL);
2592 			status = nfsd4_encode_aclname(xdr, rqstp, ace);
2593 			if (status)
2594 				goto out;
2595 		}
2596 	}
2597 out_acl:
2598 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2599 		p = xdr_reserve_space(xdr, 4);
2600 		if (!p)
2601 			goto out_resource;
2602 		*p++ = cpu_to_be32(IS_POSIXACL(dentry->d_inode) ?
2603 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2604 	}
2605 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2606 		p = xdr_reserve_space(xdr, 4);
2607 		if (!p)
2608 			goto out_resource;
2609 		*p++ = cpu_to_be32(1);
2610 	}
2611 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2612 		p = xdr_reserve_space(xdr, 4);
2613 		if (!p)
2614 			goto out_resource;
2615 		*p++ = cpu_to_be32(0);
2616 	}
2617 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2618 		p = xdr_reserve_space(xdr, 4);
2619 		if (!p)
2620 			goto out_resource;
2621 		*p++ = cpu_to_be32(1);
2622 	}
2623 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2624 		p = xdr_reserve_space(xdr, 4);
2625 		if (!p)
2626 			goto out_resource;
2627 		*p++ = cpu_to_be32(1);
2628 	}
2629 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2630 		p = xdr_reserve_space(xdr, fhp->fh_handle.fh_size + 4);
2631 		if (!p)
2632 			goto out_resource;
2633 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base,
2634 					fhp->fh_handle.fh_size);
2635 	}
2636 	if (bmval0 & FATTR4_WORD0_FILEID) {
2637 		p = xdr_reserve_space(xdr, 8);
2638 		if (!p)
2639 			goto out_resource;
2640 		p = xdr_encode_hyper(p, stat.ino);
2641 	}
2642 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2643 		p = xdr_reserve_space(xdr, 8);
2644 		if (!p)
2645 			goto out_resource;
2646 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2647 	}
2648 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2649 		p = xdr_reserve_space(xdr, 8);
2650 		if (!p)
2651 			goto out_resource;
2652 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2653 	}
2654 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2655 		p = xdr_reserve_space(xdr, 8);
2656 		if (!p)
2657 			goto out_resource;
2658 		p = xdr_encode_hyper(p, (u64) statfs.f_files);
2659 	}
2660 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2661 		status = nfsd4_encode_fs_locations(xdr, rqstp, exp);
2662 		if (status)
2663 			goto out;
2664 	}
2665 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
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_MAXFILESIZE) {
2672 		p = xdr_reserve_space(xdr, 8);
2673 		if (!p)
2674 			goto out_resource;
2675 		p = xdr_encode_hyper(p, exp->ex_path.mnt->mnt_sb->s_maxbytes);
2676 	}
2677 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2678 		p = xdr_reserve_space(xdr, 4);
2679 		if (!p)
2680 			goto out_resource;
2681 		*p++ = cpu_to_be32(255);
2682 	}
2683 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2684 		p = xdr_reserve_space(xdr, 4);
2685 		if (!p)
2686 			goto out_resource;
2687 		*p++ = cpu_to_be32(statfs.f_namelen);
2688 	}
2689 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2690 		p = xdr_reserve_space(xdr, 8);
2691 		if (!p)
2692 			goto out_resource;
2693 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2694 	}
2695 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2696 		p = xdr_reserve_space(xdr, 8);
2697 		if (!p)
2698 			goto out_resource;
2699 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2700 	}
2701 	if (bmval1 & FATTR4_WORD1_MODE) {
2702 		p = xdr_reserve_space(xdr, 4);
2703 		if (!p)
2704 			goto out_resource;
2705 		*p++ = cpu_to_be32(stat.mode & S_IALLUGO);
2706 	}
2707 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2708 		p = xdr_reserve_space(xdr, 4);
2709 		if (!p)
2710 			goto out_resource;
2711 		*p++ = cpu_to_be32(1);
2712 	}
2713 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2714 		p = xdr_reserve_space(xdr, 4);
2715 		if (!p)
2716 			goto out_resource;
2717 		*p++ = cpu_to_be32(stat.nlink);
2718 	}
2719 	if (bmval1 & FATTR4_WORD1_OWNER) {
2720 		status = nfsd4_encode_user(xdr, rqstp, stat.uid);
2721 		if (status)
2722 			goto out;
2723 	}
2724 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2725 		status = nfsd4_encode_group(xdr, rqstp, stat.gid);
2726 		if (status)
2727 			goto out;
2728 	}
2729 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2730 		p = xdr_reserve_space(xdr, 8);
2731 		if (!p)
2732 			goto out_resource;
2733 		*p++ = cpu_to_be32((u32) MAJOR(stat.rdev));
2734 		*p++ = cpu_to_be32((u32) MINOR(stat.rdev));
2735 	}
2736 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2737 		p = xdr_reserve_space(xdr, 8);
2738 		if (!p)
2739 			goto out_resource;
2740 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2741 		p = xdr_encode_hyper(p, dummy64);
2742 	}
2743 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2744 		p = xdr_reserve_space(xdr, 8);
2745 		if (!p)
2746 			goto out_resource;
2747 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2748 		p = xdr_encode_hyper(p, dummy64);
2749 	}
2750 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2751 		p = xdr_reserve_space(xdr, 8);
2752 		if (!p)
2753 			goto out_resource;
2754 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2755 		p = xdr_encode_hyper(p, dummy64);
2756 	}
2757 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2758 		p = xdr_reserve_space(xdr, 8);
2759 		if (!p)
2760 			goto out_resource;
2761 		dummy64 = (u64)stat.blocks << 9;
2762 		p = xdr_encode_hyper(p, dummy64);
2763 	}
2764 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2765 		p = xdr_reserve_space(xdr, 12);
2766 		if (!p)
2767 			goto out_resource;
2768 		p = xdr_encode_hyper(p, (s64)stat.atime.tv_sec);
2769 		*p++ = cpu_to_be32(stat.atime.tv_nsec);
2770 	}
2771 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2772 		p = xdr_reserve_space(xdr, 12);
2773 		if (!p)
2774 			goto out_resource;
2775 		*p++ = cpu_to_be32(0);
2776 		*p++ = cpu_to_be32(1);
2777 		*p++ = cpu_to_be32(0);
2778 	}
2779 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2780 		p = xdr_reserve_space(xdr, 12);
2781 		if (!p)
2782 			goto out_resource;
2783 		p = xdr_encode_hyper(p, (s64)stat.ctime.tv_sec);
2784 		*p++ = cpu_to_be32(stat.ctime.tv_nsec);
2785 	}
2786 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2787 		p = xdr_reserve_space(xdr, 12);
2788 		if (!p)
2789 			goto out_resource;
2790 		p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
2791 		*p++ = cpu_to_be32(stat.mtime.tv_nsec);
2792 	}
2793 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2794 		struct kstat parent_stat;
2795 		u64 ino = stat.ino;
2796 
2797 		p = xdr_reserve_space(xdr, 8);
2798 		if (!p)
2799                 	goto out_resource;
2800 		/*
2801 		 * Get parent's attributes if not ignoring crossmount
2802 		 * and this is the root of a cross-mounted filesystem.
2803 		 */
2804 		if (ignore_crossmnt == 0 &&
2805 		    dentry == exp->ex_path.mnt->mnt_root) {
2806 			err = get_parent_attributes(exp, &parent_stat);
2807 			if (err)
2808 				goto out_nfserr;
2809 			ino = parent_stat.ino;
2810 		}
2811 		p = xdr_encode_hyper(p, ino);
2812 	}
2813 #ifdef CONFIG_NFSD_PNFS
2814 	if (bmval1 & FATTR4_WORD1_FS_LAYOUT_TYPES) {
2815 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
2816 		if (status)
2817 			goto out;
2818 	}
2819 
2820 	if (bmval2 & FATTR4_WORD2_LAYOUT_TYPES) {
2821 		status = nfsd4_encode_layout_types(xdr, exp->ex_layout_types);
2822 		if (status)
2823 			goto out;
2824 	}
2825 
2826 	if (bmval2 & FATTR4_WORD2_LAYOUT_BLKSIZE) {
2827 		p = xdr_reserve_space(xdr, 4);
2828 		if (!p)
2829 			goto out_resource;
2830 		*p++ = cpu_to_be32(stat.blksize);
2831 	}
2832 #endif /* CONFIG_NFSD_PNFS */
2833 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2834 		status = nfsd4_encode_bitmap(xdr, NFSD_SUPPATTR_EXCLCREAT_WORD0,
2835 						  NFSD_SUPPATTR_EXCLCREAT_WORD1,
2836 						  NFSD_SUPPATTR_EXCLCREAT_WORD2);
2837 		if (status)
2838 			goto out;
2839 	}
2840 
2841 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2842 		status = nfsd4_encode_security_label(xdr, rqstp, context,
2843 								contextlen);
2844 		if (status)
2845 			goto out;
2846 	}
2847 
2848 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
2849 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
2850 	status = nfs_ok;
2851 
2852 out:
2853 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2854 	if (context)
2855 		security_release_secctx(context, contextlen);
2856 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2857 	kfree(acl);
2858 	if (tempfh) {
2859 		fh_put(tempfh);
2860 		kfree(tempfh);
2861 	}
2862 	if (status)
2863 		xdr_truncate_encode(xdr, starting_len);
2864 	return status;
2865 out_nfserr:
2866 	status = nfserrno(err);
2867 	goto out;
2868 out_resource:
2869 	status = nfserr_resource;
2870 	goto out;
2871 }
2872 
2873 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
2874 				struct xdr_buf *buf, __be32 *p, int bytes)
2875 {
2876 	xdr->scratch.iov_len = 0;
2877 	memset(buf, 0, sizeof(struct xdr_buf));
2878 	buf->head[0].iov_base = p;
2879 	buf->head[0].iov_len = 0;
2880 	buf->len = 0;
2881 	xdr->buf = buf;
2882 	xdr->iov = buf->head;
2883 	xdr->p = p;
2884 	xdr->end = (void *)p + bytes;
2885 	buf->buflen = bytes;
2886 }
2887 
2888 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
2889 			struct svc_fh *fhp, struct svc_export *exp,
2890 			struct dentry *dentry, u32 *bmval,
2891 			struct svc_rqst *rqstp, int ignore_crossmnt)
2892 {
2893 	struct xdr_buf dummy;
2894 	struct xdr_stream xdr;
2895 	__be32 ret;
2896 
2897 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
2898 	ret = nfsd4_encode_fattr(&xdr, fhp, exp, dentry, bmval, rqstp,
2899 							ignore_crossmnt);
2900 	*p = xdr.p;
2901 	return ret;
2902 }
2903 
2904 static inline int attributes_need_mount(u32 *bmval)
2905 {
2906 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2907 		return 1;
2908 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2909 		return 1;
2910 	return 0;
2911 }
2912 
2913 static __be32
2914 nfsd4_encode_dirent_fattr(struct xdr_stream *xdr, struct nfsd4_readdir *cd,
2915 			const char *name, int namlen)
2916 {
2917 	struct svc_export *exp = cd->rd_fhp->fh_export;
2918 	struct dentry *dentry;
2919 	__be32 nfserr;
2920 	int ignore_crossmnt = 0;
2921 
2922 	dentry = lookup_one_len_unlocked(name, cd->rd_fhp->fh_dentry, namlen);
2923 	if (IS_ERR(dentry))
2924 		return nfserrno(PTR_ERR(dentry));
2925 	if (d_really_is_negative(dentry)) {
2926 		/*
2927 		 * we're not holding the i_mutex here, so there's
2928 		 * a window where this directory entry could have gone
2929 		 * away.
2930 		 */
2931 		dput(dentry);
2932 		return nfserr_noent;
2933 	}
2934 
2935 	exp_get(exp);
2936 	/*
2937 	 * In the case of a mountpoint, the client may be asking for
2938 	 * attributes that are only properties of the underlying filesystem
2939 	 * as opposed to the cross-mounted file system. In such a case,
2940 	 * we will not follow the cross mount and will fill the attribtutes
2941 	 * directly from the mountpoint dentry.
2942 	 */
2943 	if (nfsd_mountpoint(dentry, exp)) {
2944 		int err;
2945 
2946 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
2947 				&& !attributes_need_mount(cd->rd_bmval)) {
2948 			ignore_crossmnt = 1;
2949 			goto out_encode;
2950 		}
2951 		/*
2952 		 * Why the heck aren't we just using nfsd_lookup??
2953 		 * Different "."/".." handling?  Something else?
2954 		 * At least, add a comment here to explain....
2955 		 */
2956 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
2957 		if (err) {
2958 			nfserr = nfserrno(err);
2959 			goto out_put;
2960 		}
2961 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
2962 		if (nfserr)
2963 			goto out_put;
2964 
2965 	}
2966 out_encode:
2967 	nfserr = nfsd4_encode_fattr(xdr, NULL, exp, dentry, cd->rd_bmval,
2968 					cd->rd_rqstp, ignore_crossmnt);
2969 out_put:
2970 	dput(dentry);
2971 	exp_put(exp);
2972 	return nfserr;
2973 }
2974 
2975 static __be32 *
2976 nfsd4_encode_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
2977 {
2978 	__be32 *p;
2979 
2980 	p = xdr_reserve_space(xdr, 20);
2981 	if (!p)
2982 		return NULL;
2983 	*p++ = htonl(2);
2984 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
2985 	*p++ = htonl(0);			 /* bmval1 */
2986 
2987 	*p++ = htonl(4);     /* attribute length */
2988 	*p++ = nfserr;       /* no htonl */
2989 	return p;
2990 }
2991 
2992 static int
2993 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
2994 		    loff_t offset, u64 ino, unsigned int d_type)
2995 {
2996 	struct readdir_cd *ccd = ccdv;
2997 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
2998 	struct xdr_stream *xdr = cd->xdr;
2999 	int start_offset = xdr->buf->len;
3000 	int cookie_offset;
3001 	u32 name_and_cookie;
3002 	int entry_bytes;
3003 	__be32 nfserr = nfserr_toosmall;
3004 	__be64 wire_offset;
3005 	__be32 *p;
3006 
3007 	/* In nfsv4, "." and ".." never make it onto the wire.. */
3008 	if (name && isdotent(name, namlen)) {
3009 		cd->common.err = nfs_ok;
3010 		return 0;
3011 	}
3012 
3013 	if (cd->cookie_offset) {
3014 		wire_offset = cpu_to_be64(offset);
3015 		write_bytes_to_xdr_buf(xdr->buf, cd->cookie_offset,
3016 							&wire_offset, 8);
3017 	}
3018 
3019 	p = xdr_reserve_space(xdr, 4);
3020 	if (!p)
3021 		goto fail;
3022 	*p++ = xdr_one;                             /* mark entry present */
3023 	cookie_offset = xdr->buf->len;
3024 	p = xdr_reserve_space(xdr, 3*4 + namlen);
3025 	if (!p)
3026 		goto fail;
3027 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
3028 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
3029 
3030 	nfserr = nfsd4_encode_dirent_fattr(xdr, cd, name, namlen);
3031 	switch (nfserr) {
3032 	case nfs_ok:
3033 		break;
3034 	case nfserr_resource:
3035 		nfserr = nfserr_toosmall;
3036 		goto fail;
3037 	case nfserr_noent:
3038 		xdr_truncate_encode(xdr, start_offset);
3039 		goto skip_entry;
3040 	default:
3041 		/*
3042 		 * If the client requested the RDATTR_ERROR attribute,
3043 		 * we stuff the error code into this attribute
3044 		 * and continue.  If this attribute was not requested,
3045 		 * then in accordance with the spec, we fail the
3046 		 * entire READDIR operation(!)
3047 		 */
3048 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
3049 			goto fail;
3050 		p = nfsd4_encode_rdattr_error(xdr, nfserr);
3051 		if (p == NULL) {
3052 			nfserr = nfserr_toosmall;
3053 			goto fail;
3054 		}
3055 	}
3056 	nfserr = nfserr_toosmall;
3057 	entry_bytes = xdr->buf->len - start_offset;
3058 	if (entry_bytes > cd->rd_maxcount)
3059 		goto fail;
3060 	cd->rd_maxcount -= entry_bytes;
3061 	/*
3062 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so
3063 	 * let's always let through the first entry, at least:
3064 	 */
3065 	if (!cd->rd_dircount)
3066 		goto fail;
3067 	name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8;
3068 	if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
3069 		goto fail;
3070 	cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
3071 
3072 	cd->cookie_offset = cookie_offset;
3073 skip_entry:
3074 	cd->common.err = nfs_ok;
3075 	return 0;
3076 fail:
3077 	xdr_truncate_encode(xdr, start_offset);
3078 	cd->common.err = nfserr;
3079 	return -EINVAL;
3080 }
3081 
3082 static __be32
3083 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
3084 {
3085 	__be32 *p;
3086 
3087 	p = xdr_reserve_space(xdr, sizeof(stateid_t));
3088 	if (!p)
3089 		return nfserr_resource;
3090 	*p++ = cpu_to_be32(sid->si_generation);
3091 	p = xdr_encode_opaque_fixed(p, &sid->si_opaque,
3092 					sizeof(stateid_opaque_t));
3093 	return 0;
3094 }
3095 
3096 static __be32
3097 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
3098 {
3099 	struct xdr_stream *xdr = &resp->xdr;
3100 	__be32 *p;
3101 
3102 	if (!nfserr) {
3103 		p = xdr_reserve_space(xdr, 8);
3104 		if (!p)
3105 			return nfserr_resource;
3106 		*p++ = cpu_to_be32(access->ac_supported);
3107 		*p++ = cpu_to_be32(access->ac_resp_access);
3108 	}
3109 	return nfserr;
3110 }
3111 
3112 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
3113 {
3114 	struct xdr_stream *xdr = &resp->xdr;
3115 	__be32 *p;
3116 
3117 	if (!nfserr) {
3118 		p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 8);
3119 		if (!p)
3120 			return nfserr_resource;
3121 		p = xdr_encode_opaque_fixed(p, bcts->sessionid.data,
3122 						NFS4_MAX_SESSIONID_LEN);
3123 		*p++ = cpu_to_be32(bcts->dir);
3124 		/* Upshifting from TCP to RDMA is not supported */
3125 		*p++ = cpu_to_be32(0);
3126 	}
3127 	return nfserr;
3128 }
3129 
3130 static __be32
3131 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
3132 {
3133 	struct xdr_stream *xdr = &resp->xdr;
3134 
3135 	if (!nfserr)
3136 		nfserr = nfsd4_encode_stateid(xdr, &close->cl_stateid);
3137 
3138 	return nfserr;
3139 }
3140 
3141 
3142 static __be32
3143 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
3144 {
3145 	struct xdr_stream *xdr = &resp->xdr;
3146 	__be32 *p;
3147 
3148 	if (!nfserr) {
3149 		p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3150 		if (!p)
3151 			return nfserr_resource;
3152 		p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
3153 						NFS4_VERIFIER_SIZE);
3154 	}
3155 	return nfserr;
3156 }
3157 
3158 static __be32
3159 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
3160 {
3161 	struct xdr_stream *xdr = &resp->xdr;
3162 	__be32 *p;
3163 
3164 	if (!nfserr) {
3165 		p = xdr_reserve_space(xdr, 20);
3166 		if (!p)
3167 			return nfserr_resource;
3168 		encode_cinfo(p, &create->cr_cinfo);
3169 		nfserr = nfsd4_encode_bitmap(xdr, create->cr_bmval[0],
3170 				create->cr_bmval[1], create->cr_bmval[2]);
3171 	}
3172 	return nfserr;
3173 }
3174 
3175 static __be32
3176 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
3177 {
3178 	struct svc_fh *fhp = getattr->ga_fhp;
3179 	struct xdr_stream *xdr = &resp->xdr;
3180 
3181 	if (nfserr)
3182 		return nfserr;
3183 
3184 	nfserr = nfsd4_encode_fattr(xdr, fhp, fhp->fh_export, fhp->fh_dentry,
3185 				    getattr->ga_bmval,
3186 				    resp->rqstp, 0);
3187 	return nfserr;
3188 }
3189 
3190 static __be32
3191 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
3192 {
3193 	struct xdr_stream *xdr = &resp->xdr;
3194 	struct svc_fh *fhp = *fhpp;
3195 	unsigned int len;
3196 	__be32 *p;
3197 
3198 	if (!nfserr) {
3199 		len = fhp->fh_handle.fh_size;
3200 		p = xdr_reserve_space(xdr, len + 4);
3201 		if (!p)
3202 			return nfserr_resource;
3203 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base, len);
3204 	}
3205 	return nfserr;
3206 }
3207 
3208 /*
3209 * Including all fields other than the name, a LOCK4denied structure requires
3210 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
3211 */
3212 static __be32
3213 nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld)
3214 {
3215 	struct xdr_netobj *conf = &ld->ld_owner;
3216 	__be32 *p;
3217 
3218 again:
3219 	p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len));
3220 	if (!p) {
3221 		/*
3222 		 * Don't fail to return the result just because we can't
3223 		 * return the conflicting open:
3224 		 */
3225 		if (conf->len) {
3226 			kfree(conf->data);
3227 			conf->len = 0;
3228 			conf->data = NULL;
3229 			goto again;
3230 		}
3231 		return nfserr_resource;
3232 	}
3233 	p = xdr_encode_hyper(p, ld->ld_start);
3234 	p = xdr_encode_hyper(p, ld->ld_length);
3235 	*p++ = cpu_to_be32(ld->ld_type);
3236 	if (conf->len) {
3237 		p = xdr_encode_opaque_fixed(p, &ld->ld_clientid, 8);
3238 		p = xdr_encode_opaque(p, conf->data, conf->len);
3239 		kfree(conf->data);
3240 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
3241 		p = xdr_encode_hyper(p, (u64)0); /* clientid */
3242 		*p++ = cpu_to_be32(0); /* length of owner name */
3243 	}
3244 	return nfserr_denied;
3245 }
3246 
3247 static __be32
3248 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
3249 {
3250 	struct xdr_stream *xdr = &resp->xdr;
3251 
3252 	if (!nfserr)
3253 		nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid);
3254 	else if (nfserr == nfserr_denied)
3255 		nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied);
3256 
3257 	return nfserr;
3258 }
3259 
3260 static __be32
3261 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
3262 {
3263 	struct xdr_stream *xdr = &resp->xdr;
3264 
3265 	if (nfserr == nfserr_denied)
3266 		nfsd4_encode_lock_denied(xdr, &lockt->lt_denied);
3267 	return nfserr;
3268 }
3269 
3270 static __be32
3271 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
3272 {
3273 	struct xdr_stream *xdr = &resp->xdr;
3274 
3275 	if (!nfserr)
3276 		nfserr = nfsd4_encode_stateid(xdr, &locku->lu_stateid);
3277 
3278 	return nfserr;
3279 }
3280 
3281 
3282 static __be32
3283 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
3284 {
3285 	struct xdr_stream *xdr = &resp->xdr;
3286 	__be32 *p;
3287 
3288 	if (!nfserr) {
3289 		p = xdr_reserve_space(xdr, 20);
3290 		if (!p)
3291 			return nfserr_resource;
3292 		p = encode_cinfo(p, &link->li_cinfo);
3293 	}
3294 	return nfserr;
3295 }
3296 
3297 
3298 static __be32
3299 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
3300 {
3301 	struct xdr_stream *xdr = &resp->xdr;
3302 	__be32 *p;
3303 
3304 	if (nfserr)
3305 		goto out;
3306 
3307 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
3308 	if (nfserr)
3309 		goto out;
3310 	p = xdr_reserve_space(xdr, 24);
3311 	if (!p)
3312 		return nfserr_resource;
3313 	p = encode_cinfo(p, &open->op_cinfo);
3314 	*p++ = cpu_to_be32(open->op_rflags);
3315 
3316 	nfserr = nfsd4_encode_bitmap(xdr, open->op_bmval[0], open->op_bmval[1],
3317 					open->op_bmval[2]);
3318 	if (nfserr)
3319 		goto out;
3320 
3321 	p = xdr_reserve_space(xdr, 4);
3322 	if (!p)
3323 		return nfserr_resource;
3324 
3325 	*p++ = cpu_to_be32(open->op_delegate_type);
3326 	switch (open->op_delegate_type) {
3327 	case NFS4_OPEN_DELEGATE_NONE:
3328 		break;
3329 	case NFS4_OPEN_DELEGATE_READ:
3330 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3331 		if (nfserr)
3332 			return nfserr;
3333 		p = xdr_reserve_space(xdr, 20);
3334 		if (!p)
3335 			return nfserr_resource;
3336 		*p++ = cpu_to_be32(open->op_recall);
3337 
3338 		/*
3339 		 * TODO: ACE's in delegations
3340 		 */
3341 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3342 		*p++ = cpu_to_be32(0);
3343 		*p++ = cpu_to_be32(0);
3344 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3345 		break;
3346 	case NFS4_OPEN_DELEGATE_WRITE:
3347 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3348 		if (nfserr)
3349 			return nfserr;
3350 		p = xdr_reserve_space(xdr, 32);
3351 		if (!p)
3352 			return nfserr_resource;
3353 		*p++ = cpu_to_be32(0);
3354 
3355 		/*
3356 		 * TODO: space_limit's in delegations
3357 		 */
3358 		*p++ = cpu_to_be32(NFS4_LIMIT_SIZE);
3359 		*p++ = cpu_to_be32(~(u32)0);
3360 		*p++ = cpu_to_be32(~(u32)0);
3361 
3362 		/*
3363 		 * TODO: ACE's in delegations
3364 		 */
3365 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3366 		*p++ = cpu_to_be32(0);
3367 		*p++ = cpu_to_be32(0);
3368 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3369 		break;
3370 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
3371 		switch (open->op_why_no_deleg) {
3372 		case WND4_CONTENTION:
3373 		case WND4_RESOURCE:
3374 			p = xdr_reserve_space(xdr, 8);
3375 			if (!p)
3376 				return nfserr_resource;
3377 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3378 			/* deleg signaling not supported yet: */
3379 			*p++ = cpu_to_be32(0);
3380 			break;
3381 		default:
3382 			p = xdr_reserve_space(xdr, 4);
3383 			if (!p)
3384 				return nfserr_resource;
3385 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3386 		}
3387 		break;
3388 	default:
3389 		BUG();
3390 	}
3391 	/* XXX save filehandle here */
3392 out:
3393 	return nfserr;
3394 }
3395 
3396 static __be32
3397 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
3398 {
3399 	struct xdr_stream *xdr = &resp->xdr;
3400 
3401 	if (!nfserr)
3402 		nfserr = nfsd4_encode_stateid(xdr, &oc->oc_resp_stateid);
3403 
3404 	return nfserr;
3405 }
3406 
3407 static __be32
3408 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
3409 {
3410 	struct xdr_stream *xdr = &resp->xdr;
3411 
3412 	if (!nfserr)
3413 		nfserr = nfsd4_encode_stateid(xdr, &od->od_stateid);
3414 
3415 	return nfserr;
3416 }
3417 
3418 static __be32 nfsd4_encode_splice_read(
3419 				struct nfsd4_compoundres *resp,
3420 				struct nfsd4_read *read,
3421 				struct file *file, unsigned long maxcount)
3422 {
3423 	struct xdr_stream *xdr = &resp->xdr;
3424 	struct xdr_buf *buf = xdr->buf;
3425 	u32 eof;
3426 	long len;
3427 	int space_left;
3428 	__be32 nfserr;
3429 	__be32 *p = xdr->p - 2;
3430 
3431 	/* Make sure there will be room for padding if needed */
3432 	if (xdr->end - xdr->p < 1)
3433 		return nfserr_resource;
3434 
3435 	len = maxcount;
3436 	nfserr = nfsd_splice_read(read->rd_rqstp, file,
3437 				  read->rd_offset, &maxcount);
3438 	if (nfserr) {
3439 		/*
3440 		 * nfsd_splice_actor may have already messed with the
3441 		 * page length; reset it so as not to confuse
3442 		 * xdr_truncate_encode:
3443 		 */
3444 		buf->page_len = 0;
3445 		return nfserr;
3446 	}
3447 
3448 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3449 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3450 
3451 	*(p++) = htonl(eof);
3452 	*(p++) = htonl(maxcount);
3453 
3454 	buf->page_len = maxcount;
3455 	buf->len += maxcount;
3456 	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
3457 							/ PAGE_SIZE;
3458 
3459 	/* Use rest of head for padding and remaining ops: */
3460 	buf->tail[0].iov_base = xdr->p;
3461 	buf->tail[0].iov_len = 0;
3462 	xdr->iov = buf->tail;
3463 	if (maxcount&3) {
3464 		int pad = 4 - (maxcount&3);
3465 
3466 		*(xdr->p++) = 0;
3467 
3468 		buf->tail[0].iov_base += maxcount&3;
3469 		buf->tail[0].iov_len = pad;
3470 		buf->len += pad;
3471 	}
3472 
3473 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
3474 				buf->buflen - buf->len);
3475 	buf->buflen = buf->len + space_left;
3476 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
3477 
3478 	return 0;
3479 }
3480 
3481 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
3482 				 struct nfsd4_read *read,
3483 				 struct file *file, unsigned long maxcount)
3484 {
3485 	struct xdr_stream *xdr = &resp->xdr;
3486 	u32 eof;
3487 	int v;
3488 	int starting_len = xdr->buf->len - 8;
3489 	long len;
3490 	int thislen;
3491 	__be32 nfserr;
3492 	__be32 tmp;
3493 	__be32 *p;
3494 	u32 zzz = 0;
3495 	int pad;
3496 
3497 	len = maxcount;
3498 	v = 0;
3499 
3500 	thislen = min_t(long, len, ((void *)xdr->end - (void *)xdr->p));
3501 	p = xdr_reserve_space(xdr, (thislen+3)&~3);
3502 	WARN_ON_ONCE(!p);
3503 	resp->rqstp->rq_vec[v].iov_base = p;
3504 	resp->rqstp->rq_vec[v].iov_len = thislen;
3505 	v++;
3506 	len -= thislen;
3507 
3508 	while (len) {
3509 		thislen = min_t(long, len, PAGE_SIZE);
3510 		p = xdr_reserve_space(xdr, (thislen+3)&~3);
3511 		WARN_ON_ONCE(!p);
3512 		resp->rqstp->rq_vec[v].iov_base = p;
3513 		resp->rqstp->rq_vec[v].iov_len = thislen;
3514 		v++;
3515 		len -= thislen;
3516 	}
3517 	read->rd_vlen = v;
3518 
3519 	len = maxcount;
3520 	nfserr = nfsd_readv(file, read->rd_offset, resp->rqstp->rq_vec,
3521 			read->rd_vlen, &maxcount);
3522 	if (nfserr)
3523 		return nfserr;
3524 	xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3));
3525 
3526 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3527 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3528 
3529 	tmp = htonl(eof);
3530 	write_bytes_to_xdr_buf(xdr->buf, starting_len    , &tmp, 4);
3531 	tmp = htonl(maxcount);
3532 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
3533 
3534 	pad = (maxcount&3) ? 4 - (maxcount&3) : 0;
3535 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 8 + maxcount,
3536 								&zzz, pad);
3537 	return 0;
3538 
3539 }
3540 
3541 static __be32
3542 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
3543 		  struct nfsd4_read *read)
3544 {
3545 	unsigned long maxcount;
3546 	struct xdr_stream *xdr = &resp->xdr;
3547 	struct file *file = read->rd_filp;
3548 	int starting_len = xdr->buf->len;
3549 	struct raparms *ra = NULL;
3550 	__be32 *p;
3551 
3552 	if (nfserr)
3553 		goto out;
3554 
3555 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
3556 	if (!p) {
3557 		WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
3558 		nfserr = nfserr_resource;
3559 		goto out;
3560 	}
3561 	if (resp->xdr.buf->page_len &&
3562 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
3563 		WARN_ON_ONCE(1);
3564 		nfserr = nfserr_resource;
3565 		goto out;
3566 	}
3567 	xdr_commit_encode(xdr);
3568 
3569 	maxcount = svc_max_payload(resp->rqstp);
3570 	maxcount = min_t(unsigned long, maxcount,
3571 			 (xdr->buf->buflen - xdr->buf->len));
3572 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
3573 
3574 	if (read->rd_tmp_file)
3575 		ra = nfsd_init_raparms(file);
3576 
3577 	if (file->f_op->splice_read &&
3578 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
3579 		nfserr = nfsd4_encode_splice_read(resp, read, file, maxcount);
3580 	else
3581 		nfserr = nfsd4_encode_readv(resp, read, file, maxcount);
3582 
3583 	if (ra)
3584 		nfsd_put_raparams(file, ra);
3585 
3586 	if (nfserr)
3587 		xdr_truncate_encode(xdr, starting_len);
3588 
3589 out:
3590 	if (file)
3591 		fput(file);
3592 	return nfserr;
3593 }
3594 
3595 static __be32
3596 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3597 {
3598 	int maxcount;
3599 	__be32 wire_count;
3600 	int zero = 0;
3601 	struct xdr_stream *xdr = &resp->xdr;
3602 	int length_offset = xdr->buf->len;
3603 	__be32 *p;
3604 
3605 	if (nfserr)
3606 		return nfserr;
3607 
3608 	p = xdr_reserve_space(xdr, 4);
3609 	if (!p)
3610 		return nfserr_resource;
3611 	maxcount = PAGE_SIZE;
3612 
3613 	p = xdr_reserve_space(xdr, maxcount);
3614 	if (!p)
3615 		return nfserr_resource;
3616 	/*
3617 	 * XXX: By default, vfs_readlink() will truncate symlinks if they
3618 	 * would overflow the buffer.  Is this kosher in NFSv4?  If not, one
3619 	 * easy fix is: if vfs_readlink() precisely fills the buffer, assume
3620 	 * that truncation occurred, and return NFS4ERR_RESOURCE.
3621 	 */
3622 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
3623 						(char *)p, &maxcount);
3624 	if (nfserr == nfserr_isdir)
3625 		nfserr = nfserr_inval;
3626 	if (nfserr) {
3627 		xdr_truncate_encode(xdr, length_offset);
3628 		return nfserr;
3629 	}
3630 
3631 	wire_count = htonl(maxcount);
3632 	write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
3633 	xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
3634 	if (maxcount & 3)
3635 		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
3636 						&zero, 4 - (maxcount&3));
3637 	return 0;
3638 }
3639 
3640 static __be32
3641 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3642 {
3643 	int maxcount;
3644 	int bytes_left;
3645 	loff_t offset;
3646 	__be64 wire_offset;
3647 	struct xdr_stream *xdr = &resp->xdr;
3648 	int starting_len = xdr->buf->len;
3649 	__be32 *p;
3650 
3651 	if (nfserr)
3652 		return nfserr;
3653 
3654 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3655 	if (!p)
3656 		return nfserr_resource;
3657 
3658 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3659 	*p++ = cpu_to_be32(0);
3660 	*p++ = cpu_to_be32(0);
3661 	resp->xdr.buf->head[0].iov_len = ((char *)resp->xdr.p)
3662 				- (char *)resp->xdr.buf->head[0].iov_base;
3663 
3664 	/*
3665 	 * Number of bytes left for directory entries allowing for the
3666 	 * final 8 bytes of the readdir and a following failed op:
3667 	 */
3668 	bytes_left = xdr->buf->buflen - xdr->buf->len
3669 			- COMPOUND_ERR_SLACK_SPACE - 8;
3670 	if (bytes_left < 0) {
3671 		nfserr = nfserr_resource;
3672 		goto err_no_verf;
3673 	}
3674 	maxcount = min_t(u32, readdir->rd_maxcount, INT_MAX);
3675 	/*
3676 	 * Note the rfc defines rd_maxcount as the size of the
3677 	 * READDIR4resok structure, which includes the verifier above
3678 	 * and the 8 bytes encoded at the end of this function:
3679 	 */
3680 	if (maxcount < 16) {
3681 		nfserr = nfserr_toosmall;
3682 		goto err_no_verf;
3683 	}
3684 	maxcount = min_t(int, maxcount-16, bytes_left);
3685 
3686 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
3687 	if (!readdir->rd_dircount)
3688 		readdir->rd_dircount = INT_MAX;
3689 
3690 	readdir->xdr = xdr;
3691 	readdir->rd_maxcount = maxcount;
3692 	readdir->common.err = 0;
3693 	readdir->cookie_offset = 0;
3694 
3695 	offset = readdir->rd_cookie;
3696 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3697 			      &offset,
3698 			      &readdir->common, nfsd4_encode_dirent);
3699 	if (nfserr == nfs_ok &&
3700 	    readdir->common.err == nfserr_toosmall &&
3701 	    xdr->buf->len == starting_len + 8) {
3702 		/* nothing encoded; which limit did we hit?: */
3703 		if (maxcount - 16 < bytes_left)
3704 			/* It was the fault of rd_maxcount: */
3705 			nfserr = nfserr_toosmall;
3706 		else
3707 			/* We ran out of buffer space: */
3708 			nfserr = nfserr_resource;
3709 	}
3710 	if (nfserr)
3711 		goto err_no_verf;
3712 
3713 	if (readdir->cookie_offset) {
3714 		wire_offset = cpu_to_be64(offset);
3715 		write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset,
3716 							&wire_offset, 8);
3717 	}
3718 
3719 	p = xdr_reserve_space(xdr, 8);
3720 	if (!p) {
3721 		WARN_ON_ONCE(1);
3722 		goto err_no_verf;
3723 	}
3724 	*p++ = 0;	/* no more entries */
3725 	*p++ = htonl(readdir->common.err == nfserr_eof);
3726 
3727 	return 0;
3728 err_no_verf:
3729 	xdr_truncate_encode(xdr, starting_len);
3730 	return nfserr;
3731 }
3732 
3733 static __be32
3734 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3735 {
3736 	struct xdr_stream *xdr = &resp->xdr;
3737 	__be32 *p;
3738 
3739 	if (!nfserr) {
3740 		p = xdr_reserve_space(xdr, 20);
3741 		if (!p)
3742 			return nfserr_resource;
3743 		p = encode_cinfo(p, &remove->rm_cinfo);
3744 	}
3745 	return nfserr;
3746 }
3747 
3748 static __be32
3749 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3750 {
3751 	struct xdr_stream *xdr = &resp->xdr;
3752 	__be32 *p;
3753 
3754 	if (!nfserr) {
3755 		p = xdr_reserve_space(xdr, 40);
3756 		if (!p)
3757 			return nfserr_resource;
3758 		p = encode_cinfo(p, &rename->rn_sinfo);
3759 		p = encode_cinfo(p, &rename->rn_tinfo);
3760 	}
3761 	return nfserr;
3762 }
3763 
3764 static __be32
3765 nfsd4_do_encode_secinfo(struct xdr_stream *xdr,
3766 			 __be32 nfserr, struct svc_export *exp)
3767 {
3768 	u32 i, nflavs, supported;
3769 	struct exp_flavor_info *flavs;
3770 	struct exp_flavor_info def_flavs[2];
3771 	__be32 *p, *flavorsp;
3772 	static bool report = true;
3773 
3774 	if (nfserr)
3775 		goto out;
3776 	nfserr = nfserr_resource;
3777 	if (exp->ex_nflavors) {
3778 		flavs = exp->ex_flavors;
3779 		nflavs = exp->ex_nflavors;
3780 	} else { /* Handling of some defaults in absence of real secinfo: */
3781 		flavs = def_flavs;
3782 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3783 			nflavs = 2;
3784 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3785 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3786 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3787 			nflavs = 1;
3788 			flavs[0].pseudoflavor
3789 					= svcauth_gss_flavor(exp->ex_client);
3790 		} else {
3791 			nflavs = 1;
3792 			flavs[0].pseudoflavor
3793 					= exp->ex_client->flavour->flavour;
3794 		}
3795 	}
3796 
3797 	supported = 0;
3798 	p = xdr_reserve_space(xdr, 4);
3799 	if (!p)
3800 		goto out;
3801 	flavorsp = p++;		/* to be backfilled later */
3802 
3803 	for (i = 0; i < nflavs; i++) {
3804 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
3805 		struct rpcsec_gss_info info;
3806 
3807 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
3808 			supported++;
3809 			p = xdr_reserve_space(xdr, 4 + 4 +
3810 					      XDR_LEN(info.oid.len) + 4 + 4);
3811 			if (!p)
3812 				goto out;
3813 			*p++ = cpu_to_be32(RPC_AUTH_GSS);
3814 			p = xdr_encode_opaque(p,  info.oid.data, info.oid.len);
3815 			*p++ = cpu_to_be32(info.qop);
3816 			*p++ = cpu_to_be32(info.service);
3817 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
3818 			supported++;
3819 			p = xdr_reserve_space(xdr, 4);
3820 			if (!p)
3821 				goto out;
3822 			*p++ = cpu_to_be32(pf);
3823 		} else {
3824 			if (report)
3825 				pr_warn("NFS: SECINFO: security flavor %u "
3826 					"is not supported\n", pf);
3827 		}
3828 	}
3829 
3830 	if (nflavs != supported)
3831 		report = false;
3832 	*flavorsp = htonl(supported);
3833 	nfserr = 0;
3834 out:
3835 	if (exp)
3836 		exp_put(exp);
3837 	return nfserr;
3838 }
3839 
3840 static __be32
3841 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3842 		     struct nfsd4_secinfo *secinfo)
3843 {
3844 	struct xdr_stream *xdr = &resp->xdr;
3845 
3846 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->si_exp);
3847 }
3848 
3849 static __be32
3850 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3851 		     struct nfsd4_secinfo_no_name *secinfo)
3852 {
3853 	struct xdr_stream *xdr = &resp->xdr;
3854 
3855 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->sin_exp);
3856 }
3857 
3858 /*
3859  * The SETATTR encode routine is special -- it always encodes a bitmap,
3860  * regardless of the error status.
3861  */
3862 static __be32
3863 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3864 {
3865 	struct xdr_stream *xdr = &resp->xdr;
3866 	__be32 *p;
3867 
3868 	p = xdr_reserve_space(xdr, 16);
3869 	if (!p)
3870 		return nfserr_resource;
3871 	if (nfserr) {
3872 		*p++ = cpu_to_be32(3);
3873 		*p++ = cpu_to_be32(0);
3874 		*p++ = cpu_to_be32(0);
3875 		*p++ = cpu_to_be32(0);
3876 	}
3877 	else {
3878 		*p++ = cpu_to_be32(3);
3879 		*p++ = cpu_to_be32(setattr->sa_bmval[0]);
3880 		*p++ = cpu_to_be32(setattr->sa_bmval[1]);
3881 		*p++ = cpu_to_be32(setattr->sa_bmval[2]);
3882 	}
3883 	return nfserr;
3884 }
3885 
3886 static __be32
3887 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3888 {
3889 	struct xdr_stream *xdr = &resp->xdr;
3890 	__be32 *p;
3891 
3892 	if (!nfserr) {
3893 		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
3894 		if (!p)
3895 			return nfserr_resource;
3896 		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
3897 		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
3898 						NFS4_VERIFIER_SIZE);
3899 	}
3900 	else if (nfserr == nfserr_clid_inuse) {
3901 		p = xdr_reserve_space(xdr, 8);
3902 		if (!p)
3903 			return nfserr_resource;
3904 		*p++ = cpu_to_be32(0);
3905 		*p++ = cpu_to_be32(0);
3906 	}
3907 	return nfserr;
3908 }
3909 
3910 static __be32
3911 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3912 {
3913 	struct xdr_stream *xdr = &resp->xdr;
3914 	__be32 *p;
3915 
3916 	if (!nfserr) {
3917 		p = xdr_reserve_space(xdr, 16);
3918 		if (!p)
3919 			return nfserr_resource;
3920 		*p++ = cpu_to_be32(write->wr_bytes_written);
3921 		*p++ = cpu_to_be32(write->wr_how_written);
3922 		p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
3923 							NFS4_VERIFIER_SIZE);
3924 	}
3925 	return nfserr;
3926 }
3927 
3928 static __be32
3929 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
3930 			 struct nfsd4_exchange_id *exid)
3931 {
3932 	struct xdr_stream *xdr = &resp->xdr;
3933 	__be32 *p;
3934 	char *major_id;
3935 	char *server_scope;
3936 	int major_id_sz;
3937 	int server_scope_sz;
3938 	int status = 0;
3939 	uint64_t minor_id = 0;
3940 
3941 	if (nfserr)
3942 		return nfserr;
3943 
3944 	major_id = utsname()->nodename;
3945 	major_id_sz = strlen(major_id);
3946 	server_scope = utsname()->nodename;
3947 	server_scope_sz = strlen(server_scope);
3948 
3949 	p = xdr_reserve_space(xdr,
3950 		8 /* eir_clientid */ +
3951 		4 /* eir_sequenceid */ +
3952 		4 /* eir_flags */ +
3953 		4 /* spr_how */);
3954 	if (!p)
3955 		return nfserr_resource;
3956 
3957 	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
3958 	*p++ = cpu_to_be32(exid->seqid);
3959 	*p++ = cpu_to_be32(exid->flags);
3960 
3961 	*p++ = cpu_to_be32(exid->spa_how);
3962 
3963 	switch (exid->spa_how) {
3964 	case SP4_NONE:
3965 		break;
3966 	case SP4_MACH_CRED:
3967 		/* spo_must_enforce bitmap: */
3968 		status = nfsd4_encode_bitmap(xdr,
3969 					exid->spo_must_enforce[0],
3970 					exid->spo_must_enforce[1],
3971 					exid->spo_must_enforce[2]);
3972 		if (status)
3973 			goto out;
3974 		/* spo_must_allow bitmap: */
3975 		status = nfsd4_encode_bitmap(xdr,
3976 					exid->spo_must_allow[0],
3977 					exid->spo_must_allow[1],
3978 					exid->spo_must_allow[2]);
3979 		if (status)
3980 			goto out;
3981 		break;
3982 	default:
3983 		WARN_ON_ONCE(1);
3984 	}
3985 
3986 	p = xdr_reserve_space(xdr,
3987 		8 /* so_minor_id */ +
3988 		4 /* so_major_id.len */ +
3989 		(XDR_QUADLEN(major_id_sz) * 4) +
3990 		4 /* eir_server_scope.len */ +
3991 		(XDR_QUADLEN(server_scope_sz) * 4) +
3992 		4 /* eir_server_impl_id.count (0) */);
3993 	if (!p)
3994 		return nfserr_resource;
3995 
3996 	/* The server_owner struct */
3997 	p = xdr_encode_hyper(p, minor_id);      /* Minor id */
3998 	/* major id */
3999 	p = xdr_encode_opaque(p, major_id, major_id_sz);
4000 
4001 	/* Server scope */
4002 	p = xdr_encode_opaque(p, server_scope, server_scope_sz);
4003 
4004 	/* Implementation id */
4005 	*p++ = cpu_to_be32(0);	/* zero length nfs_impl_id4 array */
4006 	return 0;
4007 out:
4008 	return status;
4009 }
4010 
4011 static __be32
4012 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
4013 			    struct nfsd4_create_session *sess)
4014 {
4015 	struct xdr_stream *xdr = &resp->xdr;
4016 	__be32 *p;
4017 
4018 	if (nfserr)
4019 		return nfserr;
4020 
4021 	p = xdr_reserve_space(xdr, 24);
4022 	if (!p)
4023 		return nfserr_resource;
4024 	p = xdr_encode_opaque_fixed(p, sess->sessionid.data,
4025 					NFS4_MAX_SESSIONID_LEN);
4026 	*p++ = cpu_to_be32(sess->seqid);
4027 	*p++ = cpu_to_be32(sess->flags);
4028 
4029 	p = xdr_reserve_space(xdr, 28);
4030 	if (!p)
4031 		return nfserr_resource;
4032 	*p++ = cpu_to_be32(0); /* headerpadsz */
4033 	*p++ = cpu_to_be32(sess->fore_channel.maxreq_sz);
4034 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_sz);
4035 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_cached);
4036 	*p++ = cpu_to_be32(sess->fore_channel.maxops);
4037 	*p++ = cpu_to_be32(sess->fore_channel.maxreqs);
4038 	*p++ = cpu_to_be32(sess->fore_channel.nr_rdma_attrs);
4039 
4040 	if (sess->fore_channel.nr_rdma_attrs) {
4041 		p = xdr_reserve_space(xdr, 4);
4042 		if (!p)
4043 			return nfserr_resource;
4044 		*p++ = cpu_to_be32(sess->fore_channel.rdma_attrs);
4045 	}
4046 
4047 	p = xdr_reserve_space(xdr, 28);
4048 	if (!p)
4049 		return nfserr_resource;
4050 	*p++ = cpu_to_be32(0); /* headerpadsz */
4051 	*p++ = cpu_to_be32(sess->back_channel.maxreq_sz);
4052 	*p++ = cpu_to_be32(sess->back_channel.maxresp_sz);
4053 	*p++ = cpu_to_be32(sess->back_channel.maxresp_cached);
4054 	*p++ = cpu_to_be32(sess->back_channel.maxops);
4055 	*p++ = cpu_to_be32(sess->back_channel.maxreqs);
4056 	*p++ = cpu_to_be32(sess->back_channel.nr_rdma_attrs);
4057 
4058 	if (sess->back_channel.nr_rdma_attrs) {
4059 		p = xdr_reserve_space(xdr, 4);
4060 		if (!p)
4061 			return nfserr_resource;
4062 		*p++ = cpu_to_be32(sess->back_channel.rdma_attrs);
4063 	}
4064 	return 0;
4065 }
4066 
4067 static __be32
4068 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
4069 		      struct nfsd4_sequence *seq)
4070 {
4071 	struct xdr_stream *xdr = &resp->xdr;
4072 	__be32 *p;
4073 
4074 	if (nfserr)
4075 		return nfserr;
4076 
4077 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 20);
4078 	if (!p)
4079 		return nfserr_resource;
4080 	p = xdr_encode_opaque_fixed(p, seq->sessionid.data,
4081 					NFS4_MAX_SESSIONID_LEN);
4082 	*p++ = cpu_to_be32(seq->seqid);
4083 	*p++ = cpu_to_be32(seq->slotid);
4084 	/* Note slotid's are numbered from zero: */
4085 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_highest_slotid */
4086 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_target_highest_slotid */
4087 	*p++ = cpu_to_be32(seq->status_flags);
4088 
4089 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
4090 	return 0;
4091 }
4092 
4093 static __be32
4094 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
4095 			  struct nfsd4_test_stateid *test_stateid)
4096 {
4097 	struct xdr_stream *xdr = &resp->xdr;
4098 	struct nfsd4_test_stateid_id *stateid, *next;
4099 	__be32 *p;
4100 
4101 	if (nfserr)
4102 		return nfserr;
4103 
4104 	p = xdr_reserve_space(xdr, 4 + (4 * test_stateid->ts_num_ids));
4105 	if (!p)
4106 		return nfserr_resource;
4107 	*p++ = htonl(test_stateid->ts_num_ids);
4108 
4109 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
4110 		*p++ = stateid->ts_id_status;
4111 	}
4112 
4113 	return nfserr;
4114 }
4115 
4116 #ifdef CONFIG_NFSD_PNFS
4117 static __be32
4118 nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
4119 		struct nfsd4_getdeviceinfo *gdev)
4120 {
4121 	struct xdr_stream *xdr = &resp->xdr;
4122 	const struct nfsd4_layout_ops *ops =
4123 		nfsd4_layout_ops[gdev->gd_layout_type];
4124 	u32 starting_len = xdr->buf->len, needed_len;
4125 	__be32 *p;
4126 
4127 	dprintk("%s: err %d\n", __func__, be32_to_cpu(nfserr));
4128 	if (nfserr)
4129 		goto out;
4130 
4131 	nfserr = nfserr_resource;
4132 	p = xdr_reserve_space(xdr, 4);
4133 	if (!p)
4134 		goto out;
4135 
4136 	*p++ = cpu_to_be32(gdev->gd_layout_type);
4137 
4138 	/* If maxcount is 0 then just update notifications */
4139 	if (gdev->gd_maxcount != 0) {
4140 		nfserr = ops->encode_getdeviceinfo(xdr, gdev);
4141 		if (nfserr) {
4142 			/*
4143 			 * We don't bother to burden the layout drivers with
4144 			 * enforcing gd_maxcount, just tell the client to
4145 			 * come back with a bigger buffer if it's not enough.
4146 			 */
4147 			if (xdr->buf->len + 4 > gdev->gd_maxcount)
4148 				goto toosmall;
4149 			goto out;
4150 		}
4151 	}
4152 
4153 	nfserr = nfserr_resource;
4154 	if (gdev->gd_notify_types) {
4155 		p = xdr_reserve_space(xdr, 4 + 4);
4156 		if (!p)
4157 			goto out;
4158 		*p++ = cpu_to_be32(1);			/* bitmap length */
4159 		*p++ = cpu_to_be32(gdev->gd_notify_types);
4160 	} else {
4161 		p = xdr_reserve_space(xdr, 4);
4162 		if (!p)
4163 			goto out;
4164 		*p++ = 0;
4165 	}
4166 
4167 	nfserr = 0;
4168 out:
4169 	kfree(gdev->gd_device);
4170 	dprintk("%s: done: %d\n", __func__, be32_to_cpu(nfserr));
4171 	return nfserr;
4172 
4173 toosmall:
4174 	dprintk("%s: maxcount too small\n", __func__);
4175 	needed_len = xdr->buf->len + 4 /* notifications */;
4176 	xdr_truncate_encode(xdr, starting_len);
4177 	p = xdr_reserve_space(xdr, 4);
4178 	if (!p) {
4179 		nfserr = nfserr_resource;
4180 	} else {
4181 		*p++ = cpu_to_be32(needed_len);
4182 		nfserr = nfserr_toosmall;
4183 	}
4184 	goto out;
4185 }
4186 
4187 static __be32
4188 nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr,
4189 		struct nfsd4_layoutget *lgp)
4190 {
4191 	struct xdr_stream *xdr = &resp->xdr;
4192 	const struct nfsd4_layout_ops *ops =
4193 		nfsd4_layout_ops[lgp->lg_layout_type];
4194 	__be32 *p;
4195 
4196 	dprintk("%s: err %d\n", __func__, nfserr);
4197 	if (nfserr)
4198 		goto out;
4199 
4200 	nfserr = nfserr_resource;
4201 	p = xdr_reserve_space(xdr, 36 + sizeof(stateid_opaque_t));
4202 	if (!p)
4203 		goto out;
4204 
4205 	*p++ = cpu_to_be32(1);	/* we always set return-on-close */
4206 	*p++ = cpu_to_be32(lgp->lg_sid.si_generation);
4207 	p = xdr_encode_opaque_fixed(p, &lgp->lg_sid.si_opaque,
4208 				    sizeof(stateid_opaque_t));
4209 
4210 	*p++ = cpu_to_be32(1);	/* we always return a single layout */
4211 	p = xdr_encode_hyper(p, lgp->lg_seg.offset);
4212 	p = xdr_encode_hyper(p, lgp->lg_seg.length);
4213 	*p++ = cpu_to_be32(lgp->lg_seg.iomode);
4214 	*p++ = cpu_to_be32(lgp->lg_layout_type);
4215 
4216 	nfserr = ops->encode_layoutget(xdr, lgp);
4217 out:
4218 	kfree(lgp->lg_content);
4219 	return nfserr;
4220 }
4221 
4222 static __be32
4223 nfsd4_encode_layoutcommit(struct nfsd4_compoundres *resp, __be32 nfserr,
4224 			  struct nfsd4_layoutcommit *lcp)
4225 {
4226 	struct xdr_stream *xdr = &resp->xdr;
4227 	__be32 *p;
4228 
4229 	if (nfserr)
4230 		return nfserr;
4231 
4232 	p = xdr_reserve_space(xdr, 4);
4233 	if (!p)
4234 		return nfserr_resource;
4235 	*p++ = cpu_to_be32(lcp->lc_size_chg);
4236 	if (lcp->lc_size_chg) {
4237 		p = xdr_reserve_space(xdr, 8);
4238 		if (!p)
4239 			return nfserr_resource;
4240 		p = xdr_encode_hyper(p, lcp->lc_newsize);
4241 	}
4242 
4243 	return nfs_ok;
4244 }
4245 
4246 static __be32
4247 nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
4248 		struct nfsd4_layoutreturn *lrp)
4249 {
4250 	struct xdr_stream *xdr = &resp->xdr;
4251 	__be32 *p;
4252 
4253 	if (nfserr)
4254 		return nfserr;
4255 
4256 	p = xdr_reserve_space(xdr, 4);
4257 	if (!p)
4258 		return nfserr_resource;
4259 	*p++ = cpu_to_be32(lrp->lrs_present);
4260 	if (lrp->lrs_present)
4261 		return nfsd4_encode_stateid(xdr, &lrp->lr_sid);
4262 	return nfs_ok;
4263 }
4264 #endif /* CONFIG_NFSD_PNFS */
4265 
4266 static __be32
4267 nfsd42_encode_write_res(struct nfsd4_compoundres *resp, struct nfsd42_write_res *write)
4268 {
4269 	__be32 *p;
4270 
4271 	p = xdr_reserve_space(&resp->xdr, 4 + 8 + 4 + NFS4_VERIFIER_SIZE);
4272 	if (!p)
4273 		return nfserr_resource;
4274 
4275 	*p++ = cpu_to_be32(0);
4276 	p = xdr_encode_hyper(p, write->wr_bytes_written);
4277 	*p++ = cpu_to_be32(write->wr_stable_how);
4278 	p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
4279 				    NFS4_VERIFIER_SIZE);
4280 	return nfs_ok;
4281 }
4282 
4283 static __be32
4284 nfsd4_encode_copy(struct nfsd4_compoundres *resp, __be32 nfserr,
4285 		  struct nfsd4_copy *copy)
4286 {
4287 	__be32 *p;
4288 
4289 	if (!nfserr) {
4290 		nfserr = nfsd42_encode_write_res(resp, &copy->cp_res);
4291 		if (nfserr)
4292 			return nfserr;
4293 
4294 		p = xdr_reserve_space(&resp->xdr, 4 + 4);
4295 		*p++ = cpu_to_be32(copy->cp_consecutive);
4296 		*p++ = cpu_to_be32(copy->cp_synchronous);
4297 	}
4298 	return nfserr;
4299 }
4300 
4301 static __be32
4302 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
4303 		  struct nfsd4_seek *seek)
4304 {
4305 	__be32 *p;
4306 
4307 	if (nfserr)
4308 		return nfserr;
4309 
4310 	p = xdr_reserve_space(&resp->xdr, 4 + 8);
4311 	*p++ = cpu_to_be32(seek->seek_eof);
4312 	p = xdr_encode_hyper(p, seek->seek_pos);
4313 
4314 	return nfserr;
4315 }
4316 
4317 static __be32
4318 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
4319 {
4320 	return nfserr;
4321 }
4322 
4323 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
4324 
4325 /*
4326  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
4327  * since we don't need to filter out obsolete ops as this is
4328  * done in the decoding phase.
4329  */
4330 static nfsd4_enc nfsd4_enc_ops[] = {
4331 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
4332 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
4333 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
4334 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
4335 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
4336 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4337 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
4338 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
4339 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
4340 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
4341 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
4342 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
4343 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
4344 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
4345 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4346 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
4347 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
4348 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
4349 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
4350 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4351 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
4352 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4353 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
4354 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
4355 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
4356 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
4357 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
4358 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
4359 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
4360 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
4361 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
4362 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
4363 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
4364 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
4365 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4366 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
4367 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
4368 
4369 	/* NFSv4.1 operations */
4370 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
4371 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
4372 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
4373 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
4374 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
4375 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
4376 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4377 #ifdef CONFIG_NFSD_PNFS
4378 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_getdeviceinfo,
4379 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4380 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_layoutcommit,
4381 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_layoutget,
4382 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_layoutreturn,
4383 #else
4384 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
4385 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4386 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
4387 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
4388 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4389 #endif
4390 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
4391 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
4392 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
4393 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
4394 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4395 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
4396 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
4397 
4398 	/* NFSv4.2 operations */
4399 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4400 	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_copy,
4401 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
4402 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4403 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
4404 	[OP_LAYOUTERROR]	= (nfsd4_enc)nfsd4_encode_noop,
4405 	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,
4406 	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,
4407 	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_noop,
4408 	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_noop,
4409 	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,
4410 	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,
4411 	[OP_CLONE]		= (nfsd4_enc)nfsd4_encode_noop,
4412 };
4413 
4414 /*
4415  * Calculate whether we still have space to encode repsize bytes.
4416  * There are two considerations:
4417  *     - For NFS versions >=4.1, the size of the reply must stay within
4418  *       session limits
4419  *     - For all NFS versions, we must stay within limited preallocated
4420  *       buffer space.
4421  *
4422  * This is called before the operation is processed, so can only provide
4423  * an upper estimate.  For some nonidempotent operations (such as
4424  * getattr), it's not necessarily a problem if that estimate is wrong,
4425  * as we can fail it after processing without significant side effects.
4426  */
4427 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
4428 {
4429 	struct xdr_buf *buf = &resp->rqstp->rq_res;
4430 	struct nfsd4_slot *slot = resp->cstate.slot;
4431 
4432 	if (buf->len + respsize <= buf->buflen)
4433 		return nfs_ok;
4434 	if (!nfsd4_has_session(&resp->cstate))
4435 		return nfserr_resource;
4436 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
4437 		WARN_ON_ONCE(1);
4438 		return nfserr_rep_too_big_to_cache;
4439 	}
4440 	return nfserr_rep_too_big;
4441 }
4442 
4443 void
4444 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
4445 {
4446 	struct xdr_stream *xdr = &resp->xdr;
4447 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
4448 	struct svc_rqst *rqstp = resp->rqstp;
4449 	int post_err_offset;
4450 	nfsd4_enc encoder;
4451 	__be32 *p;
4452 
4453 	p = xdr_reserve_space(xdr, 8);
4454 	if (!p) {
4455 		WARN_ON_ONCE(1);
4456 		return;
4457 	}
4458 	*p++ = cpu_to_be32(op->opnum);
4459 	post_err_offset = xdr->buf->len;
4460 
4461 	if (op->opnum == OP_ILLEGAL)
4462 		goto status;
4463 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
4464 	       !nfsd4_enc_ops[op->opnum]);
4465 	encoder = nfsd4_enc_ops[op->opnum];
4466 	op->status = encoder(resp, op->status, &op->u);
4467 	xdr_commit_encode(xdr);
4468 
4469 	/* nfsd4_check_resp_size guarantees enough room for error status */
4470 	if (!op->status) {
4471 		int space_needed = 0;
4472 		if (!nfsd4_last_compound_op(rqstp))
4473 			space_needed = COMPOUND_ERR_SLACK_SPACE;
4474 		op->status = nfsd4_check_resp_size(resp, space_needed);
4475 	}
4476 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
4477 		struct nfsd4_slot *slot = resp->cstate.slot;
4478 
4479 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
4480 			op->status = nfserr_rep_too_big_to_cache;
4481 		else
4482 			op->status = nfserr_rep_too_big;
4483 	}
4484 	if (op->status == nfserr_resource ||
4485 	    op->status == nfserr_rep_too_big ||
4486 	    op->status == nfserr_rep_too_big_to_cache) {
4487 		/*
4488 		 * The operation may have already been encoded or
4489 		 * partially encoded.  No op returns anything additional
4490 		 * in the case of one of these three errors, so we can
4491 		 * just truncate back to after the status.  But it's a
4492 		 * bug if we had to do this on a non-idempotent op:
4493 		 */
4494 		warn_on_nonidempotent_op(op);
4495 		xdr_truncate_encode(xdr, post_err_offset);
4496 	}
4497 	if (so) {
4498 		int len = xdr->buf->len - post_err_offset;
4499 
4500 		so->so_replay.rp_status = op->status;
4501 		so->so_replay.rp_buflen = len;
4502 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
4503 						so->so_replay.rp_buf, len);
4504 	}
4505 status:
4506 	/* Note that op->status is already in network byte order: */
4507 	write_bytes_to_xdr_buf(xdr->buf, post_err_offset - 4, &op->status, 4);
4508 }
4509 
4510 /*
4511  * Encode the reply stored in the stateowner reply cache
4512  *
4513  * XDR note: do not encode rp->rp_buflen: the buffer contains the
4514  * previously sent already encoded operation.
4515  */
4516 void
4517 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
4518 {
4519 	__be32 *p;
4520 	struct nfs4_replay *rp = op->replay;
4521 
4522 	BUG_ON(!rp);
4523 
4524 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
4525 	if (!p) {
4526 		WARN_ON_ONCE(1);
4527 		return;
4528 	}
4529 	*p++ = cpu_to_be32(op->opnum);
4530 	*p++ = rp->rp_status;  /* already xdr'ed */
4531 
4532 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
4533 }
4534 
4535 int
4536 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
4537 {
4538         return xdr_ressize_check(rqstp, p);
4539 }
4540 
4541 int nfsd4_release_compoundargs(void *rq, __be32 *p, void *resp)
4542 {
4543 	struct svc_rqst *rqstp = rq;
4544 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4545 
4546 	if (args->ops != args->iops) {
4547 		kfree(args->ops);
4548 		args->ops = args->iops;
4549 	}
4550 	kfree(args->tmpp);
4551 	args->tmpp = NULL;
4552 	while (args->to_free) {
4553 		struct svcxdr_tmpbuf *tb = args->to_free;
4554 		args->to_free = tb->next;
4555 		kfree(tb);
4556 	}
4557 	return 1;
4558 }
4559 
4560 int
4561 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundargs *args)
4562 {
4563 	if (rqstp->rq_arg.head[0].iov_len % 4) {
4564 		/* client is nuts */
4565 		dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)",
4566 			__func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid));
4567 		return 0;
4568 	}
4569 	args->p = p;
4570 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
4571 	args->pagelist = rqstp->rq_arg.pages;
4572 	args->pagelen = rqstp->rq_arg.page_len;
4573 	args->tmpp = NULL;
4574 	args->to_free = NULL;
4575 	args->ops = args->iops;
4576 	args->rqstp = rqstp;
4577 
4578 	return !nfsd4_decode_compound(args);
4579 }
4580 
4581 int
4582 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundres *resp)
4583 {
4584 	/*
4585 	 * All that remains is to write the tag and operation count...
4586 	 */
4587 	struct xdr_buf *buf = resp->xdr.buf;
4588 
4589 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
4590 				 buf->tail[0].iov_len);
4591 
4592 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
4593 
4594 	p = resp->tagp;
4595 	*p++ = htonl(resp->taglen);
4596 	memcpy(p, resp->tag, resp->taglen);
4597 	p += XDR_QUADLEN(resp->taglen);
4598 	*p++ = htonl(resp->opcnt);
4599 
4600 	nfsd4_sequence_done(resp);
4601 	return 1;
4602 }
4603 
4604 /*
4605  * Local variables:
4606  *  c-basic-offset: 8
4607  * End:
4608  */
4609