xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision 4bce6fce)
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/slab.h>
37 #include <linux/namei.h>
38 #include <linux/statfs.h>
39 #include <linux/utsname.h>
40 #include <linux/pagemap.h>
41 #include <linux/sunrpc/svcauth_gss.h>
42 
43 #include "idmap.h"
44 #include "acl.h"
45 #include "xdr4.h"
46 #include "vfs.h"
47 #include "state.h"
48 #include "cache.h"
49 #include "netns.h"
50 #include "pnfs.h"
51 
52 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
53 #include <linux/security.h>
54 #endif
55 
56 
57 #define NFSDDBG_FACILITY		NFSDDBG_XDR
58 
59 /*
60  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
61  * directory in order to indicate to the client that a filesystem boundary is present
62  * We use a fixed fsid for a referral
63  */
64 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
65 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
66 
67 static __be32
68 check_filename(char *str, int len)
69 {
70 	int i;
71 
72 	if (len == 0)
73 		return nfserr_inval;
74 	if (isdotent(str, len))
75 		return nfserr_badname;
76 	for (i = 0; i < len; i++)
77 		if (str[i] == '/')
78 			return nfserr_badname;
79 	return 0;
80 }
81 
82 #define DECODE_HEAD				\
83 	__be32 *p;				\
84 	__be32 status
85 #define DECODE_TAIL				\
86 	status = 0;				\
87 out:						\
88 	return status;				\
89 xdr_error:					\
90 	dprintk("NFSD: xdr error (%s:%d)\n",	\
91 			__FILE__, __LINE__);	\
92 	status = nfserr_bad_xdr;		\
93 	goto out
94 
95 #define READMEM(x,nbytes) do {			\
96 	x = (char *)p;				\
97 	p += XDR_QUADLEN(nbytes);		\
98 } while (0)
99 #define SAVEMEM(x,nbytes) do {			\
100 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
101  		savemem(argp, p, nbytes) :	\
102  		(char *)p)) {			\
103 		dprintk("NFSD: xdr error (%s:%d)\n", \
104 				__FILE__, __LINE__); \
105 		goto xdr_error;			\
106 		}				\
107 	p += XDR_QUADLEN(nbytes);		\
108 } while (0)
109 #define COPYMEM(x,nbytes) do {			\
110 	memcpy((x), p, nbytes);			\
111 	p += XDR_QUADLEN(nbytes);		\
112 } while (0)
113 
114 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
115 #define READ_BUF(nbytes)  do {			\
116 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
117 		p = argp->p;			\
118 		argp->p += XDR_QUADLEN(nbytes);	\
119 	} else if (!(p = read_buf(argp, nbytes))) { \
120 		dprintk("NFSD: xdr error (%s:%d)\n", \
121 				__FILE__, __LINE__); \
122 		goto xdr_error;			\
123 	}					\
124 } while (0)
125 
126 static void next_decode_page(struct nfsd4_compoundargs *argp)
127 {
128 	argp->p = page_address(argp->pagelist[0]);
129 	argp->pagelist++;
130 	if (argp->pagelen < PAGE_SIZE) {
131 		argp->end = argp->p + (argp->pagelen>>2);
132 		argp->pagelen = 0;
133 	} else {
134 		argp->end = argp->p + (PAGE_SIZE>>2);
135 		argp->pagelen -= PAGE_SIZE;
136 	}
137 }
138 
139 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
140 {
141 	/* We want more bytes than seem to be available.
142 	 * Maybe we need a new page, maybe we have just run out
143 	 */
144 	unsigned int avail = (char *)argp->end - (char *)argp->p;
145 	__be32 *p;
146 	if (avail + argp->pagelen < nbytes)
147 		return NULL;
148 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
149 		return NULL;
150 	/* ok, we can do it with the current plus the next page */
151 	if (nbytes <= sizeof(argp->tmp))
152 		p = argp->tmp;
153 	else {
154 		kfree(argp->tmpp);
155 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
156 		if (!p)
157 			return NULL;
158 
159 	}
160 	/*
161 	 * The following memcpy is safe because read_buf is always
162 	 * called with nbytes > avail, and the two cases above both
163 	 * guarantee p points to at least nbytes bytes.
164 	 */
165 	memcpy(p, argp->p, avail);
166 	next_decode_page(argp);
167 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
168 	argp->p += XDR_QUADLEN(nbytes - avail);
169 	return p;
170 }
171 
172 static int zero_clientid(clientid_t *clid)
173 {
174 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
175 }
176 
177 /**
178  * svcxdr_tmpalloc - allocate memory to be freed after compound processing
179  * @argp: NFSv4 compound argument structure
180  * @p: pointer to be freed (with kfree())
181  *
182  * Marks @p to be freed when processing the compound operation
183  * described in @argp finishes.
184  */
185 static void *
186 svcxdr_tmpalloc(struct nfsd4_compoundargs *argp, u32 len)
187 {
188 	struct svcxdr_tmpbuf *tb;
189 
190 	tb = kmalloc(sizeof(*tb) + len, GFP_KERNEL);
191 	if (!tb)
192 		return NULL;
193 	tb->next = argp->to_free;
194 	argp->to_free = tb;
195 	return tb->buf;
196 }
197 
198 /*
199  * For xdr strings that need to be passed to other kernel api's
200  * as null-terminated strings.
201  *
202  * Note null-terminating in place usually isn't safe since the
203  * buffer might end on a page boundary.
204  */
205 static char *
206 svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len)
207 {
208 	char *p = svcxdr_tmpalloc(argp, len + 1);
209 
210 	if (!p)
211 		return NULL;
212 	memcpy(p, buf, len);
213 	p[len] = '\0';
214 	return p;
215 }
216 
217 /**
218  * savemem - duplicate a chunk of memory for later processing
219  * @argp: NFSv4 compound argument structure to be freed with
220  * @p: pointer to be duplicated
221  * @nbytes: length to be duplicated
222  *
223  * Returns a pointer to a copy of @nbytes bytes of memory at @p
224  * that are preserved until processing of the NFSv4 compound
225  * operation described by @argp finishes.
226  */
227 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
228 {
229 	void *ret;
230 
231 	ret = svcxdr_tmpalloc(argp, nbytes);
232 	if (!ret)
233 		return NULL;
234 	memcpy(ret, p, nbytes);
235 	return ret;
236 }
237 
238 /*
239  * We require the high 32 bits of 'seconds' to be 0, and
240  * we ignore all 32 bits of 'nseconds'.
241  */
242 static __be32
243 nfsd4_decode_time(struct nfsd4_compoundargs *argp, struct timespec *tv)
244 {
245 	DECODE_HEAD;
246 	u64 sec;
247 
248 	READ_BUF(12);
249 	p = xdr_decode_hyper(p, &sec);
250 	tv->tv_sec = sec;
251 	tv->tv_nsec = be32_to_cpup(p++);
252 	if (tv->tv_nsec >= (u32)1000000000)
253 		return nfserr_inval;
254 
255 	DECODE_TAIL;
256 }
257 
258 static __be32
259 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
260 {
261 	u32 bmlen;
262 	DECODE_HEAD;
263 
264 	bmval[0] = 0;
265 	bmval[1] = 0;
266 	bmval[2] = 0;
267 
268 	READ_BUF(4);
269 	bmlen = be32_to_cpup(p++);
270 	if (bmlen > 1000)
271 		goto xdr_error;
272 
273 	READ_BUF(bmlen << 2);
274 	if (bmlen > 0)
275 		bmval[0] = be32_to_cpup(p++);
276 	if (bmlen > 1)
277 		bmval[1] = be32_to_cpup(p++);
278 	if (bmlen > 2)
279 		bmval[2] = be32_to_cpup(p++);
280 
281 	DECODE_TAIL;
282 }
283 
284 static __be32
285 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
286 		   struct iattr *iattr, struct nfs4_acl **acl,
287 		   struct xdr_netobj *label)
288 {
289 	int expected_len, len = 0;
290 	u32 dummy32;
291 	char *buf;
292 
293 	DECODE_HEAD;
294 	iattr->ia_valid = 0;
295 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
296 		return status;
297 
298 	READ_BUF(4);
299 	expected_len = be32_to_cpup(p++);
300 
301 	if (bmval[0] & FATTR4_WORD0_SIZE) {
302 		READ_BUF(8);
303 		len += 8;
304 		p = xdr_decode_hyper(p, &iattr->ia_size);
305 		iattr->ia_valid |= ATTR_SIZE;
306 	}
307 	if (bmval[0] & FATTR4_WORD0_ACL) {
308 		u32 nace;
309 		struct nfs4_ace *ace;
310 
311 		READ_BUF(4); len += 4;
312 		nace = be32_to_cpup(p++);
313 
314 		if (nace > NFS4_ACL_MAX)
315 			return nfserr_fbig;
316 
317 		*acl = svcxdr_tmpalloc(argp, nfs4_acl_bytes(nace));
318 		if (*acl == NULL)
319 			return nfserr_jukebox;
320 
321 		(*acl)->naces = nace;
322 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
323 			READ_BUF(16); len += 16;
324 			ace->type = be32_to_cpup(p++);
325 			ace->flag = be32_to_cpup(p++);
326 			ace->access_mask = be32_to_cpup(p++);
327 			dummy32 = be32_to_cpup(p++);
328 			READ_BUF(dummy32);
329 			len += XDR_QUADLEN(dummy32) << 2;
330 			READMEM(buf, dummy32);
331 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
332 			status = nfs_ok;
333 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
334 				;
335 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
336 				status = nfsd_map_name_to_gid(argp->rqstp,
337 						buf, dummy32, &ace->who_gid);
338 			else
339 				status = nfsd_map_name_to_uid(argp->rqstp,
340 						buf, dummy32, &ace->who_uid);
341 			if (status)
342 				return status;
343 		}
344 	} else
345 		*acl = NULL;
346 	if (bmval[1] & FATTR4_WORD1_MODE) {
347 		READ_BUF(4);
348 		len += 4;
349 		iattr->ia_mode = be32_to_cpup(p++);
350 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
351 		iattr->ia_valid |= ATTR_MODE;
352 	}
353 	if (bmval[1] & FATTR4_WORD1_OWNER) {
354 		READ_BUF(4);
355 		len += 4;
356 		dummy32 = be32_to_cpup(p++);
357 		READ_BUF(dummy32);
358 		len += (XDR_QUADLEN(dummy32) << 2);
359 		READMEM(buf, dummy32);
360 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
361 			return status;
362 		iattr->ia_valid |= ATTR_UID;
363 	}
364 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
365 		READ_BUF(4);
366 		len += 4;
367 		dummy32 = be32_to_cpup(p++);
368 		READ_BUF(dummy32);
369 		len += (XDR_QUADLEN(dummy32) << 2);
370 		READMEM(buf, dummy32);
371 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
372 			return status;
373 		iattr->ia_valid |= ATTR_GID;
374 	}
375 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
376 		READ_BUF(4);
377 		len += 4;
378 		dummy32 = be32_to_cpup(p++);
379 		switch (dummy32) {
380 		case NFS4_SET_TO_CLIENT_TIME:
381 			len += 12;
382 			status = nfsd4_decode_time(argp, &iattr->ia_atime);
383 			if (status)
384 				return status;
385 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
386 			break;
387 		case NFS4_SET_TO_SERVER_TIME:
388 			iattr->ia_valid |= ATTR_ATIME;
389 			break;
390 		default:
391 			goto xdr_error;
392 		}
393 	}
394 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
395 		READ_BUF(4);
396 		len += 4;
397 		dummy32 = be32_to_cpup(p++);
398 		switch (dummy32) {
399 		case NFS4_SET_TO_CLIENT_TIME:
400 			len += 12;
401 			status = nfsd4_decode_time(argp, &iattr->ia_mtime);
402 			if (status)
403 				return status;
404 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
405 			break;
406 		case NFS4_SET_TO_SERVER_TIME:
407 			iattr->ia_valid |= ATTR_MTIME;
408 			break;
409 		default:
410 			goto xdr_error;
411 		}
412 	}
413 
414 	label->len = 0;
415 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
416 	if (bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
417 		READ_BUF(4);
418 		len += 4;
419 		dummy32 = be32_to_cpup(p++); /* lfs: we don't use it */
420 		READ_BUF(4);
421 		len += 4;
422 		dummy32 = be32_to_cpup(p++); /* pi: we don't use it either */
423 		READ_BUF(4);
424 		len += 4;
425 		dummy32 = be32_to_cpup(p++);
426 		READ_BUF(dummy32);
427 		if (dummy32 > NFS4_MAXLABELLEN)
428 			return nfserr_badlabel;
429 		len += (XDR_QUADLEN(dummy32) << 2);
430 		READMEM(buf, dummy32);
431 		label->len = dummy32;
432 		label->data = svcxdr_dupstr(argp, buf, dummy32);
433 		if (!label->data)
434 			return nfserr_jukebox;
435 	}
436 #endif
437 
438 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
439 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
440 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2)
441 		READ_BUF(expected_len - len);
442 	else if (len != expected_len)
443 		goto xdr_error;
444 
445 	DECODE_TAIL;
446 }
447 
448 static __be32
449 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
450 {
451 	DECODE_HEAD;
452 
453 	READ_BUF(sizeof(stateid_t));
454 	sid->si_generation = be32_to_cpup(p++);
455 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
456 
457 	DECODE_TAIL;
458 }
459 
460 static __be32
461 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
462 {
463 	DECODE_HEAD;
464 
465 	READ_BUF(4);
466 	access->ac_req_access = be32_to_cpup(p++);
467 
468 	DECODE_TAIL;
469 }
470 
471 static __be32 nfsd4_decode_cb_sec(struct nfsd4_compoundargs *argp, struct nfsd4_cb_sec *cbs)
472 {
473 	DECODE_HEAD;
474 	u32 dummy, uid, gid;
475 	char *machine_name;
476 	int i;
477 	int nr_secflavs;
478 
479 	/* callback_sec_params4 */
480 	READ_BUF(4);
481 	nr_secflavs = be32_to_cpup(p++);
482 	if (nr_secflavs)
483 		cbs->flavor = (u32)(-1);
484 	else
485 		/* Is this legal? Be generous, take it to mean AUTH_NONE: */
486 		cbs->flavor = 0;
487 	for (i = 0; i < nr_secflavs; ++i) {
488 		READ_BUF(4);
489 		dummy = be32_to_cpup(p++);
490 		switch (dummy) {
491 		case RPC_AUTH_NULL:
492 			/* Nothing to read */
493 			if (cbs->flavor == (u32)(-1))
494 				cbs->flavor = RPC_AUTH_NULL;
495 			break;
496 		case RPC_AUTH_UNIX:
497 			READ_BUF(8);
498 			/* stamp */
499 			dummy = be32_to_cpup(p++);
500 
501 			/* machine name */
502 			dummy = be32_to_cpup(p++);
503 			READ_BUF(dummy);
504 			SAVEMEM(machine_name, dummy);
505 
506 			/* uid, gid */
507 			READ_BUF(8);
508 			uid = be32_to_cpup(p++);
509 			gid = be32_to_cpup(p++);
510 
511 			/* more gids */
512 			READ_BUF(4);
513 			dummy = be32_to_cpup(p++);
514 			READ_BUF(dummy * 4);
515 			if (cbs->flavor == (u32)(-1)) {
516 				kuid_t kuid = make_kuid(&init_user_ns, uid);
517 				kgid_t kgid = make_kgid(&init_user_ns, gid);
518 				if (uid_valid(kuid) && gid_valid(kgid)) {
519 					cbs->uid = kuid;
520 					cbs->gid = kgid;
521 					cbs->flavor = RPC_AUTH_UNIX;
522 				} else {
523 					dprintk("RPC_AUTH_UNIX with invalid"
524 						"uid or gid ignoring!\n");
525 				}
526 			}
527 			break;
528 		case RPC_AUTH_GSS:
529 			dprintk("RPC_AUTH_GSS callback secflavor "
530 				"not supported!\n");
531 			READ_BUF(8);
532 			/* gcbp_service */
533 			dummy = be32_to_cpup(p++);
534 			/* gcbp_handle_from_server */
535 			dummy = be32_to_cpup(p++);
536 			READ_BUF(dummy);
537 			p += XDR_QUADLEN(dummy);
538 			/* gcbp_handle_from_client */
539 			READ_BUF(4);
540 			dummy = be32_to_cpup(p++);
541 			READ_BUF(dummy);
542 			break;
543 		default:
544 			dprintk("Illegal callback secflavor\n");
545 			return nfserr_inval;
546 		}
547 	}
548 	DECODE_TAIL;
549 }
550 
551 static __be32 nfsd4_decode_backchannel_ctl(struct nfsd4_compoundargs *argp, struct nfsd4_backchannel_ctl *bc)
552 {
553 	DECODE_HEAD;
554 
555 	READ_BUF(4);
556 	bc->bc_cb_program = be32_to_cpup(p++);
557 	nfsd4_decode_cb_sec(argp, &bc->bc_cb_sec);
558 
559 	DECODE_TAIL;
560 }
561 
562 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
563 {
564 	DECODE_HEAD;
565 
566 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
567 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
568 	bcts->dir = be32_to_cpup(p++);
569 	/* XXX: skipping ctsa_use_conn_in_rdma_mode.  Perhaps Tom Tucker
570 	 * could help us figure out we should be using it. */
571 	DECODE_TAIL;
572 }
573 
574 static __be32
575 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
576 {
577 	DECODE_HEAD;
578 
579 	READ_BUF(4);
580 	close->cl_seqid = be32_to_cpup(p++);
581 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
582 
583 	DECODE_TAIL;
584 }
585 
586 
587 static __be32
588 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
589 {
590 	DECODE_HEAD;
591 
592 	READ_BUF(12);
593 	p = xdr_decode_hyper(p, &commit->co_offset);
594 	commit->co_count = be32_to_cpup(p++);
595 
596 	DECODE_TAIL;
597 }
598 
599 static __be32
600 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
601 {
602 	DECODE_HEAD;
603 
604 	READ_BUF(4);
605 	create->cr_type = be32_to_cpup(p++);
606 	switch (create->cr_type) {
607 	case NF4LNK:
608 		READ_BUF(4);
609 		create->cr_datalen = be32_to_cpup(p++);
610 		READ_BUF(create->cr_datalen);
611 		create->cr_data = svcxdr_dupstr(argp, p, create->cr_datalen);
612 		if (!create->cr_data)
613 			return nfserr_jukebox;
614 		break;
615 	case NF4BLK:
616 	case NF4CHR:
617 		READ_BUF(8);
618 		create->cr_specdata1 = be32_to_cpup(p++);
619 		create->cr_specdata2 = be32_to_cpup(p++);
620 		break;
621 	case NF4SOCK:
622 	case NF4FIFO:
623 	case NF4DIR:
624 	default:
625 		break;
626 	}
627 
628 	READ_BUF(4);
629 	create->cr_namelen = be32_to_cpup(p++);
630 	READ_BUF(create->cr_namelen);
631 	SAVEMEM(create->cr_name, create->cr_namelen);
632 	if ((status = check_filename(create->cr_name, create->cr_namelen)))
633 		return status;
634 
635 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
636 				    &create->cr_acl, &create->cr_label);
637 	if (status)
638 		goto out;
639 
640 	DECODE_TAIL;
641 }
642 
643 static inline __be32
644 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
645 {
646 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
647 }
648 
649 static inline __be32
650 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
651 {
652 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
653 }
654 
655 static __be32
656 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
657 {
658 	DECODE_HEAD;
659 
660 	READ_BUF(4);
661 	link->li_namelen = be32_to_cpup(p++);
662 	READ_BUF(link->li_namelen);
663 	SAVEMEM(link->li_name, link->li_namelen);
664 	if ((status = check_filename(link->li_name, link->li_namelen)))
665 		return status;
666 
667 	DECODE_TAIL;
668 }
669 
670 static __be32
671 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
672 {
673 	DECODE_HEAD;
674 
675 	/*
676 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
677 	*/
678 	READ_BUF(28);
679 	lock->lk_type = be32_to_cpup(p++);
680 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
681 		goto xdr_error;
682 	lock->lk_reclaim = be32_to_cpup(p++);
683 	p = xdr_decode_hyper(p, &lock->lk_offset);
684 	p = xdr_decode_hyper(p, &lock->lk_length);
685 	lock->lk_is_new = be32_to_cpup(p++);
686 
687 	if (lock->lk_is_new) {
688 		READ_BUF(4);
689 		lock->lk_new_open_seqid = be32_to_cpup(p++);
690 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
691 		if (status)
692 			return status;
693 		READ_BUF(8 + sizeof(clientid_t));
694 		lock->lk_new_lock_seqid = be32_to_cpup(p++);
695 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
696 		lock->lk_new_owner.len = be32_to_cpup(p++);
697 		READ_BUF(lock->lk_new_owner.len);
698 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
699 	} else {
700 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
701 		if (status)
702 			return status;
703 		READ_BUF(4);
704 		lock->lk_old_lock_seqid = be32_to_cpup(p++);
705 	}
706 
707 	DECODE_TAIL;
708 }
709 
710 static __be32
711 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
712 {
713 	DECODE_HEAD;
714 
715 	READ_BUF(32);
716 	lockt->lt_type = be32_to_cpup(p++);
717 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
718 		goto xdr_error;
719 	p = xdr_decode_hyper(p, &lockt->lt_offset);
720 	p = xdr_decode_hyper(p, &lockt->lt_length);
721 	COPYMEM(&lockt->lt_clientid, 8);
722 	lockt->lt_owner.len = be32_to_cpup(p++);
723 	READ_BUF(lockt->lt_owner.len);
724 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
725 
726 	DECODE_TAIL;
727 }
728 
729 static __be32
730 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
731 {
732 	DECODE_HEAD;
733 
734 	READ_BUF(8);
735 	locku->lu_type = be32_to_cpup(p++);
736 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
737 		goto xdr_error;
738 	locku->lu_seqid = be32_to_cpup(p++);
739 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
740 	if (status)
741 		return status;
742 	READ_BUF(16);
743 	p = xdr_decode_hyper(p, &locku->lu_offset);
744 	p = xdr_decode_hyper(p, &locku->lu_length);
745 
746 	DECODE_TAIL;
747 }
748 
749 static __be32
750 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
751 {
752 	DECODE_HEAD;
753 
754 	READ_BUF(4);
755 	lookup->lo_len = be32_to_cpup(p++);
756 	READ_BUF(lookup->lo_len);
757 	SAVEMEM(lookup->lo_name, lookup->lo_len);
758 	if ((status = check_filename(lookup->lo_name, lookup->lo_len)))
759 		return status;
760 
761 	DECODE_TAIL;
762 }
763 
764 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
765 {
766 	__be32 *p;
767 	u32 w;
768 
769 	READ_BUF(4);
770 	w = be32_to_cpup(p++);
771 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
772 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
773 	if (deleg_when)
774 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
775 
776 	switch (w & NFS4_SHARE_ACCESS_MASK) {
777 	case NFS4_SHARE_ACCESS_READ:
778 	case NFS4_SHARE_ACCESS_WRITE:
779 	case NFS4_SHARE_ACCESS_BOTH:
780 		break;
781 	default:
782 		return nfserr_bad_xdr;
783 	}
784 	w &= ~NFS4_SHARE_ACCESS_MASK;
785 	if (!w)
786 		return nfs_ok;
787 	if (!argp->minorversion)
788 		return nfserr_bad_xdr;
789 	switch (w & NFS4_SHARE_WANT_MASK) {
790 	case NFS4_SHARE_WANT_NO_PREFERENCE:
791 	case NFS4_SHARE_WANT_READ_DELEG:
792 	case NFS4_SHARE_WANT_WRITE_DELEG:
793 	case NFS4_SHARE_WANT_ANY_DELEG:
794 	case NFS4_SHARE_WANT_NO_DELEG:
795 	case NFS4_SHARE_WANT_CANCEL:
796 		break;
797 	default:
798 		return nfserr_bad_xdr;
799 	}
800 	w &= ~NFS4_SHARE_WANT_MASK;
801 	if (!w)
802 		return nfs_ok;
803 
804 	if (!deleg_when)	/* open_downgrade */
805 		return nfserr_inval;
806 	switch (w) {
807 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
808 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
809 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
810 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
811 		return nfs_ok;
812 	}
813 xdr_error:
814 	return nfserr_bad_xdr;
815 }
816 
817 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
818 {
819 	__be32 *p;
820 
821 	READ_BUF(4);
822 	*x = be32_to_cpup(p++);
823 	/* Note: unlinke access bits, deny bits may be zero. */
824 	if (*x & ~NFS4_SHARE_DENY_BOTH)
825 		return nfserr_bad_xdr;
826 	return nfs_ok;
827 xdr_error:
828 	return nfserr_bad_xdr;
829 }
830 
831 static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
832 {
833 	__be32 *p;
834 
835 	READ_BUF(4);
836 	o->len = be32_to_cpup(p++);
837 
838 	if (o->len == 0 || o->len > NFS4_OPAQUE_LIMIT)
839 		return nfserr_bad_xdr;
840 
841 	READ_BUF(o->len);
842 	SAVEMEM(o->data, o->len);
843 	return nfs_ok;
844 xdr_error:
845 	return nfserr_bad_xdr;
846 }
847 
848 static __be32
849 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
850 {
851 	DECODE_HEAD;
852 	u32 dummy;
853 
854 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
855 	open->op_iattr.ia_valid = 0;
856 	open->op_openowner = NULL;
857 
858 	open->op_xdr_error = 0;
859 	/* seqid, share_access, share_deny, clientid, ownerlen */
860 	READ_BUF(4);
861 	open->op_seqid = be32_to_cpup(p++);
862 	/* decode, yet ignore deleg_when until supported */
863 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
864 					   &open->op_deleg_want, &dummy);
865 	if (status)
866 		goto xdr_error;
867 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
868 	if (status)
869 		goto xdr_error;
870 	READ_BUF(sizeof(clientid_t));
871 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
872 	status = nfsd4_decode_opaque(argp, &open->op_owner);
873 	if (status)
874 		goto xdr_error;
875 	READ_BUF(4);
876 	open->op_create = be32_to_cpup(p++);
877 	switch (open->op_create) {
878 	case NFS4_OPEN_NOCREATE:
879 		break;
880 	case NFS4_OPEN_CREATE:
881 		READ_BUF(4);
882 		open->op_createmode = be32_to_cpup(p++);
883 		switch (open->op_createmode) {
884 		case NFS4_CREATE_UNCHECKED:
885 		case NFS4_CREATE_GUARDED:
886 			status = nfsd4_decode_fattr(argp, open->op_bmval,
887 				&open->op_iattr, &open->op_acl, &open->op_label);
888 			if (status)
889 				goto out;
890 			break;
891 		case NFS4_CREATE_EXCLUSIVE:
892 			READ_BUF(NFS4_VERIFIER_SIZE);
893 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
894 			break;
895 		case NFS4_CREATE_EXCLUSIVE4_1:
896 			if (argp->minorversion < 1)
897 				goto xdr_error;
898 			READ_BUF(NFS4_VERIFIER_SIZE);
899 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
900 			status = nfsd4_decode_fattr(argp, open->op_bmval,
901 				&open->op_iattr, &open->op_acl, &open->op_label);
902 			if (status)
903 				goto out;
904 			break;
905 		default:
906 			goto xdr_error;
907 		}
908 		break;
909 	default:
910 		goto xdr_error;
911 	}
912 
913 	/* open_claim */
914 	READ_BUF(4);
915 	open->op_claim_type = be32_to_cpup(p++);
916 	switch (open->op_claim_type) {
917 	case NFS4_OPEN_CLAIM_NULL:
918 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
919 		READ_BUF(4);
920 		open->op_fname.len = be32_to_cpup(p++);
921 		READ_BUF(open->op_fname.len);
922 		SAVEMEM(open->op_fname.data, open->op_fname.len);
923 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
924 			return status;
925 		break;
926 	case NFS4_OPEN_CLAIM_PREVIOUS:
927 		READ_BUF(4);
928 		open->op_delegate_type = be32_to_cpup(p++);
929 		break;
930 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
931 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
932 		if (status)
933 			return status;
934 		READ_BUF(4);
935 		open->op_fname.len = be32_to_cpup(p++);
936 		READ_BUF(open->op_fname.len);
937 		SAVEMEM(open->op_fname.data, open->op_fname.len);
938 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
939 			return status;
940 		break;
941 	case NFS4_OPEN_CLAIM_FH:
942 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
943 		if (argp->minorversion < 1)
944 			goto xdr_error;
945 		/* void */
946 		break;
947 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
948 		if (argp->minorversion < 1)
949 			goto xdr_error;
950 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
951 		if (status)
952 			return status;
953 		break;
954 	default:
955 		goto xdr_error;
956 	}
957 
958 	DECODE_TAIL;
959 }
960 
961 static __be32
962 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
963 {
964 	DECODE_HEAD;
965 
966 	if (argp->minorversion >= 1)
967 		return nfserr_notsupp;
968 
969 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
970 	if (status)
971 		return status;
972 	READ_BUF(4);
973 	open_conf->oc_seqid = be32_to_cpup(p++);
974 
975 	DECODE_TAIL;
976 }
977 
978 static __be32
979 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
980 {
981 	DECODE_HEAD;
982 
983 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
984 	if (status)
985 		return status;
986 	READ_BUF(4);
987 	open_down->od_seqid = be32_to_cpup(p++);
988 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
989 					   &open_down->od_deleg_want, NULL);
990 	if (status)
991 		return status;
992 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
993 	if (status)
994 		return status;
995 	DECODE_TAIL;
996 }
997 
998 static __be32
999 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
1000 {
1001 	DECODE_HEAD;
1002 
1003 	READ_BUF(4);
1004 	putfh->pf_fhlen = be32_to_cpup(p++);
1005 	if (putfh->pf_fhlen > NFS4_FHSIZE)
1006 		goto xdr_error;
1007 	READ_BUF(putfh->pf_fhlen);
1008 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
1009 
1010 	DECODE_TAIL;
1011 }
1012 
1013 static __be32
1014 nfsd4_decode_putpubfh(struct nfsd4_compoundargs *argp, void *p)
1015 {
1016 	if (argp->minorversion == 0)
1017 		return nfs_ok;
1018 	return nfserr_notsupp;
1019 }
1020 
1021 static __be32
1022 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
1023 {
1024 	DECODE_HEAD;
1025 
1026 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
1027 	if (status)
1028 		return status;
1029 	READ_BUF(12);
1030 	p = xdr_decode_hyper(p, &read->rd_offset);
1031 	read->rd_length = be32_to_cpup(p++);
1032 
1033 	DECODE_TAIL;
1034 }
1035 
1036 static __be32
1037 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
1038 {
1039 	DECODE_HEAD;
1040 
1041 	READ_BUF(24);
1042 	p = xdr_decode_hyper(p, &readdir->rd_cookie);
1043 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
1044 	readdir->rd_dircount = be32_to_cpup(p++);
1045 	readdir->rd_maxcount = be32_to_cpup(p++);
1046 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
1047 		goto out;
1048 
1049 	DECODE_TAIL;
1050 }
1051 
1052 static __be32
1053 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
1054 {
1055 	DECODE_HEAD;
1056 
1057 	READ_BUF(4);
1058 	remove->rm_namelen = be32_to_cpup(p++);
1059 	READ_BUF(remove->rm_namelen);
1060 	SAVEMEM(remove->rm_name, remove->rm_namelen);
1061 	if ((status = check_filename(remove->rm_name, remove->rm_namelen)))
1062 		return status;
1063 
1064 	DECODE_TAIL;
1065 }
1066 
1067 static __be32
1068 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
1069 {
1070 	DECODE_HEAD;
1071 
1072 	READ_BUF(4);
1073 	rename->rn_snamelen = be32_to_cpup(p++);
1074 	READ_BUF(rename->rn_snamelen + 4);
1075 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1076 	rename->rn_tnamelen = be32_to_cpup(p++);
1077 	READ_BUF(rename->rn_tnamelen);
1078 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1079 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1080 		return status;
1081 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1082 		return status;
1083 
1084 	DECODE_TAIL;
1085 }
1086 
1087 static __be32
1088 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1089 {
1090 	DECODE_HEAD;
1091 
1092 	if (argp->minorversion >= 1)
1093 		return nfserr_notsupp;
1094 
1095 	READ_BUF(sizeof(clientid_t));
1096 	COPYMEM(clientid, sizeof(clientid_t));
1097 
1098 	DECODE_TAIL;
1099 }
1100 
1101 static __be32
1102 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1103 		     struct nfsd4_secinfo *secinfo)
1104 {
1105 	DECODE_HEAD;
1106 
1107 	READ_BUF(4);
1108 	secinfo->si_namelen = be32_to_cpup(p++);
1109 	READ_BUF(secinfo->si_namelen);
1110 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1111 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1112 	if (status)
1113 		return status;
1114 	DECODE_TAIL;
1115 }
1116 
1117 static __be32
1118 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1119 		     struct nfsd4_secinfo_no_name *sin)
1120 {
1121 	DECODE_HEAD;
1122 
1123 	READ_BUF(4);
1124 	sin->sin_style = be32_to_cpup(p++);
1125 	DECODE_TAIL;
1126 }
1127 
1128 static __be32
1129 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1130 {
1131 	__be32 status;
1132 
1133 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1134 	if (status)
1135 		return status;
1136 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1137 				  &setattr->sa_acl, &setattr->sa_label);
1138 }
1139 
1140 static __be32
1141 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1142 {
1143 	DECODE_HEAD;
1144 
1145 	if (argp->minorversion >= 1)
1146 		return nfserr_notsupp;
1147 
1148 	READ_BUF(NFS4_VERIFIER_SIZE);
1149 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1150 
1151 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1152 	if (status)
1153 		return nfserr_bad_xdr;
1154 	READ_BUF(8);
1155 	setclientid->se_callback_prog = be32_to_cpup(p++);
1156 	setclientid->se_callback_netid_len = be32_to_cpup(p++);
1157 
1158 	READ_BUF(setclientid->se_callback_netid_len + 4);
1159 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1160 	setclientid->se_callback_addr_len = be32_to_cpup(p++);
1161 
1162 	READ_BUF(setclientid->se_callback_addr_len + 4);
1163 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1164 	setclientid->se_callback_ident = be32_to_cpup(p++);
1165 
1166 	DECODE_TAIL;
1167 }
1168 
1169 static __be32
1170 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1171 {
1172 	DECODE_HEAD;
1173 
1174 	if (argp->minorversion >= 1)
1175 		return nfserr_notsupp;
1176 
1177 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1178 	COPYMEM(&scd_c->sc_clientid, 8);
1179 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1180 
1181 	DECODE_TAIL;
1182 }
1183 
1184 /* Also used for NVERIFY */
1185 static __be32
1186 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1187 {
1188 	DECODE_HEAD;
1189 
1190 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1191 		goto out;
1192 
1193 	/* For convenience's sake, we compare raw xdr'd attributes in
1194 	 * nfsd4_proc_verify */
1195 
1196 	READ_BUF(4);
1197 	verify->ve_attrlen = be32_to_cpup(p++);
1198 	READ_BUF(verify->ve_attrlen);
1199 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1200 
1201 	DECODE_TAIL;
1202 }
1203 
1204 static __be32
1205 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1206 {
1207 	int avail;
1208 	int len;
1209 	DECODE_HEAD;
1210 
1211 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1212 	if (status)
1213 		return status;
1214 	READ_BUF(16);
1215 	p = xdr_decode_hyper(p, &write->wr_offset);
1216 	write->wr_stable_how = be32_to_cpup(p++);
1217 	if (write->wr_stable_how > 2)
1218 		goto xdr_error;
1219 	write->wr_buflen = be32_to_cpup(p++);
1220 
1221 	/* Sorry .. no magic macros for this.. *
1222 	 * READ_BUF(write->wr_buflen);
1223 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1224 	 */
1225 	avail = (char*)argp->end - (char*)argp->p;
1226 	if (avail + argp->pagelen < write->wr_buflen) {
1227 		dprintk("NFSD: xdr error (%s:%d)\n",
1228 				__FILE__, __LINE__);
1229 		goto xdr_error;
1230 	}
1231 	write->wr_head.iov_base = p;
1232 	write->wr_head.iov_len = avail;
1233 	write->wr_pagelist = argp->pagelist;
1234 
1235 	len = XDR_QUADLEN(write->wr_buflen) << 2;
1236 	if (len >= avail) {
1237 		int pages;
1238 
1239 		len -= avail;
1240 
1241 		pages = len >> PAGE_SHIFT;
1242 		argp->pagelist += pages;
1243 		argp->pagelen -= pages * PAGE_SIZE;
1244 		len -= pages * PAGE_SIZE;
1245 
1246 		argp->p = (__be32 *)page_address(argp->pagelist[0]);
1247 		argp->pagelist++;
1248 		argp->end = argp->p + XDR_QUADLEN(PAGE_SIZE);
1249 	}
1250 	argp->p += XDR_QUADLEN(len);
1251 
1252 	DECODE_TAIL;
1253 }
1254 
1255 static __be32
1256 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1257 {
1258 	DECODE_HEAD;
1259 
1260 	if (argp->minorversion >= 1)
1261 		return nfserr_notsupp;
1262 
1263 	READ_BUF(12);
1264 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1265 	rlockowner->rl_owner.len = be32_to_cpup(p++);
1266 	READ_BUF(rlockowner->rl_owner.len);
1267 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1268 
1269 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1270 		return nfserr_inval;
1271 	DECODE_TAIL;
1272 }
1273 
1274 static __be32
1275 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1276 			 struct nfsd4_exchange_id *exid)
1277 {
1278 	int dummy, tmp;
1279 	DECODE_HEAD;
1280 
1281 	READ_BUF(NFS4_VERIFIER_SIZE);
1282 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1283 
1284 	status = nfsd4_decode_opaque(argp, &exid->clname);
1285 	if (status)
1286 		return nfserr_bad_xdr;
1287 
1288 	READ_BUF(4);
1289 	exid->flags = be32_to_cpup(p++);
1290 
1291 	/* Ignore state_protect4_a */
1292 	READ_BUF(4);
1293 	exid->spa_how = be32_to_cpup(p++);
1294 	switch (exid->spa_how) {
1295 	case SP4_NONE:
1296 		break;
1297 	case SP4_MACH_CRED:
1298 		/* spo_must_enforce */
1299 		READ_BUF(4);
1300 		dummy = be32_to_cpup(p++);
1301 		READ_BUF(dummy * 4);
1302 		p += dummy;
1303 
1304 		/* spo_must_allow */
1305 		READ_BUF(4);
1306 		dummy = be32_to_cpup(p++);
1307 		READ_BUF(dummy * 4);
1308 		p += dummy;
1309 		break;
1310 	case SP4_SSV:
1311 		/* ssp_ops */
1312 		READ_BUF(4);
1313 		dummy = be32_to_cpup(p++);
1314 		READ_BUF(dummy * 4);
1315 		p += dummy;
1316 
1317 		READ_BUF(4);
1318 		dummy = be32_to_cpup(p++);
1319 		READ_BUF(dummy * 4);
1320 		p += dummy;
1321 
1322 		/* ssp_hash_algs<> */
1323 		READ_BUF(4);
1324 		tmp = be32_to_cpup(p++);
1325 		while (tmp--) {
1326 			READ_BUF(4);
1327 			dummy = be32_to_cpup(p++);
1328 			READ_BUF(dummy);
1329 			p += XDR_QUADLEN(dummy);
1330 		}
1331 
1332 		/* ssp_encr_algs<> */
1333 		READ_BUF(4);
1334 		tmp = be32_to_cpup(p++);
1335 		while (tmp--) {
1336 			READ_BUF(4);
1337 			dummy = be32_to_cpup(p++);
1338 			READ_BUF(dummy);
1339 			p += XDR_QUADLEN(dummy);
1340 		}
1341 
1342 		/* ssp_window and ssp_num_gss_handles */
1343 		READ_BUF(8);
1344 		dummy = be32_to_cpup(p++);
1345 		dummy = be32_to_cpup(p++);
1346 		break;
1347 	default:
1348 		goto xdr_error;
1349 	}
1350 
1351 	/* Ignore Implementation ID */
1352 	READ_BUF(4);    /* nfs_impl_id4 array length */
1353 	dummy = be32_to_cpup(p++);
1354 
1355 	if (dummy > 1)
1356 		goto xdr_error;
1357 
1358 	if (dummy == 1) {
1359 		/* nii_domain */
1360 		READ_BUF(4);
1361 		dummy = be32_to_cpup(p++);
1362 		READ_BUF(dummy);
1363 		p += XDR_QUADLEN(dummy);
1364 
1365 		/* nii_name */
1366 		READ_BUF(4);
1367 		dummy = be32_to_cpup(p++);
1368 		READ_BUF(dummy);
1369 		p += XDR_QUADLEN(dummy);
1370 
1371 		/* nii_date */
1372 		READ_BUF(12);
1373 		p += 3;
1374 	}
1375 	DECODE_TAIL;
1376 }
1377 
1378 static __be32
1379 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1380 			    struct nfsd4_create_session *sess)
1381 {
1382 	DECODE_HEAD;
1383 	u32 dummy;
1384 
1385 	READ_BUF(16);
1386 	COPYMEM(&sess->clientid, 8);
1387 	sess->seqid = be32_to_cpup(p++);
1388 	sess->flags = be32_to_cpup(p++);
1389 
1390 	/* Fore channel attrs */
1391 	READ_BUF(28);
1392 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1393 	sess->fore_channel.maxreq_sz = be32_to_cpup(p++);
1394 	sess->fore_channel.maxresp_sz = be32_to_cpup(p++);
1395 	sess->fore_channel.maxresp_cached = be32_to_cpup(p++);
1396 	sess->fore_channel.maxops = be32_to_cpup(p++);
1397 	sess->fore_channel.maxreqs = be32_to_cpup(p++);
1398 	sess->fore_channel.nr_rdma_attrs = be32_to_cpup(p++);
1399 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1400 		READ_BUF(4);
1401 		sess->fore_channel.rdma_attrs = be32_to_cpup(p++);
1402 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1403 		dprintk("Too many fore channel attr bitmaps!\n");
1404 		goto xdr_error;
1405 	}
1406 
1407 	/* Back channel attrs */
1408 	READ_BUF(28);
1409 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1410 	sess->back_channel.maxreq_sz = be32_to_cpup(p++);
1411 	sess->back_channel.maxresp_sz = be32_to_cpup(p++);
1412 	sess->back_channel.maxresp_cached = be32_to_cpup(p++);
1413 	sess->back_channel.maxops = be32_to_cpup(p++);
1414 	sess->back_channel.maxreqs = be32_to_cpup(p++);
1415 	sess->back_channel.nr_rdma_attrs = be32_to_cpup(p++);
1416 	if (sess->back_channel.nr_rdma_attrs == 1) {
1417 		READ_BUF(4);
1418 		sess->back_channel.rdma_attrs = be32_to_cpup(p++);
1419 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1420 		dprintk("Too many back channel attr bitmaps!\n");
1421 		goto xdr_error;
1422 	}
1423 
1424 	READ_BUF(4);
1425 	sess->callback_prog = be32_to_cpup(p++);
1426 	nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1427 	DECODE_TAIL;
1428 }
1429 
1430 static __be32
1431 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1432 			     struct nfsd4_destroy_session *destroy_session)
1433 {
1434 	DECODE_HEAD;
1435 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1436 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1437 
1438 	DECODE_TAIL;
1439 }
1440 
1441 static __be32
1442 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1443 			  struct nfsd4_free_stateid *free_stateid)
1444 {
1445 	DECODE_HEAD;
1446 
1447 	READ_BUF(sizeof(stateid_t));
1448 	free_stateid->fr_stateid.si_generation = be32_to_cpup(p++);
1449 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1450 
1451 	DECODE_TAIL;
1452 }
1453 
1454 static __be32
1455 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1456 		      struct nfsd4_sequence *seq)
1457 {
1458 	DECODE_HEAD;
1459 
1460 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1461 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1462 	seq->seqid = be32_to_cpup(p++);
1463 	seq->slotid = be32_to_cpup(p++);
1464 	seq->maxslots = be32_to_cpup(p++);
1465 	seq->cachethis = be32_to_cpup(p++);
1466 
1467 	DECODE_TAIL;
1468 }
1469 
1470 static __be32
1471 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1472 {
1473 	int i;
1474 	__be32 *p, status;
1475 	struct nfsd4_test_stateid_id *stateid;
1476 
1477 	READ_BUF(4);
1478 	test_stateid->ts_num_ids = ntohl(*p++);
1479 
1480 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1481 
1482 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1483 		stateid = svcxdr_tmpalloc(argp, sizeof(*stateid));
1484 		if (!stateid) {
1485 			status = nfserrno(-ENOMEM);
1486 			goto out;
1487 		}
1488 
1489 		INIT_LIST_HEAD(&stateid->ts_id_list);
1490 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1491 
1492 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1493 		if (status)
1494 			goto out;
1495 	}
1496 
1497 	status = 0;
1498 out:
1499 	return status;
1500 xdr_error:
1501 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1502 	status = nfserr_bad_xdr;
1503 	goto out;
1504 }
1505 
1506 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1507 {
1508 	DECODE_HEAD;
1509 
1510 	READ_BUF(8);
1511 	COPYMEM(&dc->clientid, 8);
1512 
1513 	DECODE_TAIL;
1514 }
1515 
1516 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1517 {
1518 	DECODE_HEAD;
1519 
1520 	READ_BUF(4);
1521 	rc->rca_one_fs = be32_to_cpup(p++);
1522 
1523 	DECODE_TAIL;
1524 }
1525 
1526 #ifdef CONFIG_NFSD_PNFS
1527 static __be32
1528 nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp,
1529 		struct nfsd4_getdeviceinfo *gdev)
1530 {
1531 	DECODE_HEAD;
1532 	u32 num, i;
1533 
1534 	READ_BUF(sizeof(struct nfsd4_deviceid) + 3 * 4);
1535 	COPYMEM(&gdev->gd_devid, sizeof(struct nfsd4_deviceid));
1536 	gdev->gd_layout_type = be32_to_cpup(p++);
1537 	gdev->gd_maxcount = be32_to_cpup(p++);
1538 	num = be32_to_cpup(p++);
1539 	if (num) {
1540 		READ_BUF(4 * num);
1541 		gdev->gd_notify_types = be32_to_cpup(p++);
1542 		for (i = 1; i < num; i++) {
1543 			if (be32_to_cpup(p++)) {
1544 				status = nfserr_inval;
1545 				goto out;
1546 			}
1547 		}
1548 	}
1549 	DECODE_TAIL;
1550 }
1551 
1552 static __be32
1553 nfsd4_decode_layoutget(struct nfsd4_compoundargs *argp,
1554 		struct nfsd4_layoutget *lgp)
1555 {
1556 	DECODE_HEAD;
1557 
1558 	READ_BUF(36);
1559 	lgp->lg_signal = be32_to_cpup(p++);
1560 	lgp->lg_layout_type = be32_to_cpup(p++);
1561 	lgp->lg_seg.iomode = be32_to_cpup(p++);
1562 	p = xdr_decode_hyper(p, &lgp->lg_seg.offset);
1563 	p = xdr_decode_hyper(p, &lgp->lg_seg.length);
1564 	p = xdr_decode_hyper(p, &lgp->lg_minlength);
1565 
1566 	status = nfsd4_decode_stateid(argp, &lgp->lg_sid);
1567 	if (status)
1568 		return status;
1569 
1570 	READ_BUF(4);
1571 	lgp->lg_maxcount = be32_to_cpup(p++);
1572 
1573 	DECODE_TAIL;
1574 }
1575 
1576 static __be32
1577 nfsd4_decode_layoutcommit(struct nfsd4_compoundargs *argp,
1578 		struct nfsd4_layoutcommit *lcp)
1579 {
1580 	DECODE_HEAD;
1581 	u32 timechange;
1582 
1583 	READ_BUF(20);
1584 	p = xdr_decode_hyper(p, &lcp->lc_seg.offset);
1585 	p = xdr_decode_hyper(p, &lcp->lc_seg.length);
1586 	lcp->lc_reclaim = be32_to_cpup(p++);
1587 
1588 	status = nfsd4_decode_stateid(argp, &lcp->lc_sid);
1589 	if (status)
1590 		return status;
1591 
1592 	READ_BUF(4);
1593 	lcp->lc_newoffset = be32_to_cpup(p++);
1594 	if (lcp->lc_newoffset) {
1595 		READ_BUF(8);
1596 		p = xdr_decode_hyper(p, &lcp->lc_last_wr);
1597 	} else
1598 		lcp->lc_last_wr = 0;
1599 	READ_BUF(4);
1600 	timechange = be32_to_cpup(p++);
1601 	if (timechange) {
1602 		status = nfsd4_decode_time(argp, &lcp->lc_mtime);
1603 		if (status)
1604 			return status;
1605 	} else {
1606 		lcp->lc_mtime.tv_nsec = UTIME_NOW;
1607 	}
1608 	READ_BUF(8);
1609 	lcp->lc_layout_type = be32_to_cpup(p++);
1610 
1611 	/*
1612 	 * Save the layout update in XDR format and let the layout driver deal
1613 	 * with it later.
1614 	 */
1615 	lcp->lc_up_len = be32_to_cpup(p++);
1616 	if (lcp->lc_up_len > 0) {
1617 		READ_BUF(lcp->lc_up_len);
1618 		READMEM(lcp->lc_up_layout, lcp->lc_up_len);
1619 	}
1620 
1621 	DECODE_TAIL;
1622 }
1623 
1624 static __be32
1625 nfsd4_decode_layoutreturn(struct nfsd4_compoundargs *argp,
1626 		struct nfsd4_layoutreturn *lrp)
1627 {
1628 	DECODE_HEAD;
1629 
1630 	READ_BUF(16);
1631 	lrp->lr_reclaim = be32_to_cpup(p++);
1632 	lrp->lr_layout_type = be32_to_cpup(p++);
1633 	lrp->lr_seg.iomode = be32_to_cpup(p++);
1634 	lrp->lr_return_type = be32_to_cpup(p++);
1635 	if (lrp->lr_return_type == RETURN_FILE) {
1636 		READ_BUF(16);
1637 		p = xdr_decode_hyper(p, &lrp->lr_seg.offset);
1638 		p = xdr_decode_hyper(p, &lrp->lr_seg.length);
1639 
1640 		status = nfsd4_decode_stateid(argp, &lrp->lr_sid);
1641 		if (status)
1642 			return status;
1643 
1644 		READ_BUF(4);
1645 		lrp->lrf_body_len = be32_to_cpup(p++);
1646 		if (lrp->lrf_body_len > 0) {
1647 			READ_BUF(lrp->lrf_body_len);
1648 			READMEM(lrp->lrf_body, lrp->lrf_body_len);
1649 		}
1650 	} else {
1651 		lrp->lr_seg.offset = 0;
1652 		lrp->lr_seg.length = NFS4_MAX_UINT64;
1653 	}
1654 
1655 	DECODE_TAIL;
1656 }
1657 #endif /* CONFIG_NFSD_PNFS */
1658 
1659 static __be32
1660 nfsd4_decode_fallocate(struct nfsd4_compoundargs *argp,
1661 		       struct nfsd4_fallocate *fallocate)
1662 {
1663 	DECODE_HEAD;
1664 
1665 	status = nfsd4_decode_stateid(argp, &fallocate->falloc_stateid);
1666 	if (status)
1667 		return status;
1668 
1669 	READ_BUF(16);
1670 	p = xdr_decode_hyper(p, &fallocate->falloc_offset);
1671 	xdr_decode_hyper(p, &fallocate->falloc_length);
1672 
1673 	DECODE_TAIL;
1674 }
1675 
1676 static __be32
1677 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
1678 {
1679 	DECODE_HEAD;
1680 
1681 	status = nfsd4_decode_stateid(argp, &seek->seek_stateid);
1682 	if (status)
1683 		return status;
1684 
1685 	READ_BUF(8 + 4);
1686 	p = xdr_decode_hyper(p, &seek->seek_offset);
1687 	seek->seek_whence = be32_to_cpup(p);
1688 
1689 	DECODE_TAIL;
1690 }
1691 
1692 static __be32
1693 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1694 {
1695 	return nfs_ok;
1696 }
1697 
1698 static __be32
1699 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1700 {
1701 	return nfserr_notsupp;
1702 }
1703 
1704 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1705 
1706 static nfsd4_dec nfsd4_dec_ops[] = {
1707 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1708 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1709 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1710 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1711 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1712 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1713 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1714 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1715 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1716 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1717 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1718 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1719 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1720 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1721 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1722 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1723 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1724 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1725 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1726 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1727 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_putpubfh,
1728 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1729 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1730 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1731 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1732 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1733 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1734 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1735 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1736 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1737 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1738 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1739 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1740 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1741 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1742 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1743 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1744 
1745 	/* new operations for NFSv4.1 */
1746 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_backchannel_ctl,
1747 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1748 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1749 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1750 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1751 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
1752 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1753 #ifdef CONFIG_NFSD_PNFS
1754 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_getdeviceinfo,
1755 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1756 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_layoutcommit,
1757 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_layoutget,
1758 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_layoutreturn,
1759 #else
1760 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1761 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1762 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1763 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1764 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1765 #endif
1766 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1767 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1768 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1769 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
1770 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1771 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
1772 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1773 
1774 	/* new operations for NFSv4.2 */
1775 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1776 	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_notsupp,
1777 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
1778 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1779 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1780 	[OP_LAYOUTERROR]	= (nfsd4_dec)nfsd4_decode_notsupp,
1781 	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1782 	[OP_OFFLOAD_CANCEL]	= (nfsd4_dec)nfsd4_decode_notsupp,
1783 	[OP_OFFLOAD_STATUS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1784 	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_notsupp,
1785 	[OP_SEEK]		= (nfsd4_dec)nfsd4_decode_seek,
1786 	[OP_WRITE_SAME]		= (nfsd4_dec)nfsd4_decode_notsupp,
1787 };
1788 
1789 static inline bool
1790 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
1791 {
1792 	if (op->opnum < FIRST_NFS4_OP)
1793 		return false;
1794 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
1795 		return false;
1796 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
1797 		return false;
1798 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
1799 		return false;
1800 	return true;
1801 }
1802 
1803 static __be32
1804 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1805 {
1806 	DECODE_HEAD;
1807 	struct nfsd4_op *op;
1808 	bool cachethis = false;
1809 	int auth_slack= argp->rqstp->rq_auth_slack;
1810 	int max_reply = auth_slack + 8; /* opcnt, status */
1811 	int readcount = 0;
1812 	int readbytes = 0;
1813 	int i;
1814 
1815 	READ_BUF(4);
1816 	argp->taglen = be32_to_cpup(p++);
1817 	READ_BUF(argp->taglen + 8);
1818 	SAVEMEM(argp->tag, argp->taglen);
1819 	argp->minorversion = be32_to_cpup(p++);
1820 	argp->opcnt = be32_to_cpup(p++);
1821 	max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
1822 
1823 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1824 		goto xdr_error;
1825 	if (argp->opcnt > 100)
1826 		goto xdr_error;
1827 
1828 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1829 		argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1830 		if (!argp->ops) {
1831 			argp->ops = argp->iops;
1832 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1833 			goto xdr_error;
1834 		}
1835 	}
1836 
1837 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
1838 		argp->opcnt = 0;
1839 
1840 	for (i = 0; i < argp->opcnt; i++) {
1841 		op = &argp->ops[i];
1842 		op->replay = NULL;
1843 
1844 		READ_BUF(4);
1845 		op->opnum = be32_to_cpup(p++);
1846 
1847 		if (nfsd4_opnum_in_range(argp, op))
1848 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
1849 		else {
1850 			op->opnum = OP_ILLEGAL;
1851 			op->status = nfserr_op_illegal;
1852 		}
1853 		/*
1854 		 * We'll try to cache the result in the DRC if any one
1855 		 * op in the compound wants to be cached:
1856 		 */
1857 		cachethis |= nfsd4_cache_this_op(op);
1858 
1859 		if (op->opnum == OP_READ) {
1860 			readcount++;
1861 			readbytes += nfsd4_max_reply(argp->rqstp, op);
1862 		} else
1863 			max_reply += nfsd4_max_reply(argp->rqstp, op);
1864 		/*
1865 		 * OP_LOCK may return a conflicting lock.  (Special case
1866 		 * because it will just skip encoding this if it runs
1867 		 * out of xdr buffer space, and it is the only operation
1868 		 * that behaves this way.)
1869 		 */
1870 		if (op->opnum == OP_LOCK)
1871 			max_reply += NFS4_OPAQUE_LIMIT;
1872 
1873 		if (op->status) {
1874 			argp->opcnt = i+1;
1875 			break;
1876 		}
1877 	}
1878 	/* Sessions make the DRC unnecessary: */
1879 	if (argp->minorversion)
1880 		cachethis = false;
1881 	svc_reserve(argp->rqstp, max_reply + readbytes);
1882 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1883 
1884 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
1885 		clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
1886 
1887 	DECODE_TAIL;
1888 }
1889 
1890 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode)
1891 {
1892 	if (IS_I_VERSION(inode)) {
1893 		p = xdr_encode_hyper(p, inode->i_version);
1894 	} else {
1895 		*p++ = cpu_to_be32(stat->ctime.tv_sec);
1896 		*p++ = cpu_to_be32(stat->ctime.tv_nsec);
1897 	}
1898 	return p;
1899 }
1900 
1901 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
1902 {
1903 	*p++ = cpu_to_be32(c->atomic);
1904 	if (c->change_supported) {
1905 		p = xdr_encode_hyper(p, c->before_change);
1906 		p = xdr_encode_hyper(p, c->after_change);
1907 	} else {
1908 		*p++ = cpu_to_be32(c->before_ctime_sec);
1909 		*p++ = cpu_to_be32(c->before_ctime_nsec);
1910 		*p++ = cpu_to_be32(c->after_ctime_sec);
1911 		*p++ = cpu_to_be32(c->after_ctime_nsec);
1912 	}
1913 	return p;
1914 }
1915 
1916 /* Encode as an array of strings the string given with components
1917  * separated @sep, escaped with esc_enter and esc_exit.
1918  */
1919 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
1920 					  char *components, char esc_enter,
1921 					  char esc_exit)
1922 {
1923 	__be32 *p;
1924 	__be32 pathlen;
1925 	int pathlen_offset;
1926 	int strlen, count=0;
1927 	char *str, *end, *next;
1928 
1929 	dprintk("nfsd4_encode_components(%s)\n", components);
1930 
1931 	pathlen_offset = xdr->buf->len;
1932 	p = xdr_reserve_space(xdr, 4);
1933 	if (!p)
1934 		return nfserr_resource;
1935 	p++; /* We will fill this in with @count later */
1936 
1937 	end = str = components;
1938 	while (*end) {
1939 		bool found_esc = false;
1940 
1941 		/* try to parse as esc_start, ..., esc_end, sep */
1942 		if (*str == esc_enter) {
1943 			for (; *end && (*end != esc_exit); end++)
1944 				/* find esc_exit or end of string */;
1945 			next = end + 1;
1946 			if (*end && (!*next || *next == sep)) {
1947 				str++;
1948 				found_esc = true;
1949 			}
1950 		}
1951 
1952 		if (!found_esc)
1953 			for (; *end && (*end != sep); end++)
1954 				/* find sep or end of string */;
1955 
1956 		strlen = end - str;
1957 		if (strlen) {
1958 			p = xdr_reserve_space(xdr, strlen + 4);
1959 			if (!p)
1960 				return nfserr_resource;
1961 			p = xdr_encode_opaque(p, str, strlen);
1962 			count++;
1963 		}
1964 		else
1965 			end++;
1966 		if (found_esc)
1967 			end = next;
1968 
1969 		str = end;
1970 	}
1971 	pathlen = htonl(count);
1972 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
1973 	return 0;
1974 }
1975 
1976 /* Encode as an array of strings the string given with components
1977  * separated @sep.
1978  */
1979 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
1980 				      char *components)
1981 {
1982 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
1983 }
1984 
1985 /*
1986  * encode a location element of a fs_locations structure
1987  */
1988 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
1989 					struct nfsd4_fs_location *location)
1990 {
1991 	__be32 status;
1992 
1993 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
1994 						'[', ']');
1995 	if (status)
1996 		return status;
1997 	status = nfsd4_encode_components(xdr, '/', location->path);
1998 	if (status)
1999 		return status;
2000 	return 0;
2001 }
2002 
2003 /*
2004  * Encode a path in RFC3530 'pathname4' format
2005  */
2006 static __be32 nfsd4_encode_path(struct xdr_stream *xdr,
2007 				const struct path *root,
2008 				const struct path *path)
2009 {
2010 	struct path cur = *path;
2011 	__be32 *p;
2012 	struct dentry **components = NULL;
2013 	unsigned int ncomponents = 0;
2014 	__be32 err = nfserr_jukebox;
2015 
2016 	dprintk("nfsd4_encode_components(");
2017 
2018 	path_get(&cur);
2019 	/* First walk the path up to the nfsd root, and store the
2020 	 * dentries/path components in an array.
2021 	 */
2022 	for (;;) {
2023 		if (path_equal(&cur, root))
2024 			break;
2025 		if (cur.dentry == cur.mnt->mnt_root) {
2026 			if (follow_up(&cur))
2027 				continue;
2028 			goto out_free;
2029 		}
2030 		if ((ncomponents & 15) == 0) {
2031 			struct dentry **new;
2032 			new = krealloc(components,
2033 					sizeof(*new) * (ncomponents + 16),
2034 					GFP_KERNEL);
2035 			if (!new)
2036 				goto out_free;
2037 			components = new;
2038 		}
2039 		components[ncomponents++] = cur.dentry;
2040 		cur.dentry = dget_parent(cur.dentry);
2041 	}
2042 	err = nfserr_resource;
2043 	p = xdr_reserve_space(xdr, 4);
2044 	if (!p)
2045 		goto out_free;
2046 	*p++ = cpu_to_be32(ncomponents);
2047 
2048 	while (ncomponents) {
2049 		struct dentry *dentry = components[ncomponents - 1];
2050 		unsigned int len;
2051 
2052 		spin_lock(&dentry->d_lock);
2053 		len = dentry->d_name.len;
2054 		p = xdr_reserve_space(xdr, len + 4);
2055 		if (!p) {
2056 			spin_unlock(&dentry->d_lock);
2057 			goto out_free;
2058 		}
2059 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
2060 		dprintk("/%pd", dentry);
2061 		spin_unlock(&dentry->d_lock);
2062 		dput(dentry);
2063 		ncomponents--;
2064 	}
2065 
2066 	err = 0;
2067 out_free:
2068 	dprintk(")\n");
2069 	while (ncomponents)
2070 		dput(components[--ncomponents]);
2071 	kfree(components);
2072 	path_put(&cur);
2073 	return err;
2074 }
2075 
2076 static __be32 nfsd4_encode_fsloc_fsroot(struct xdr_stream *xdr,
2077 			struct svc_rqst *rqstp, const struct path *path)
2078 {
2079 	struct svc_export *exp_ps;
2080 	__be32 res;
2081 
2082 	exp_ps = rqst_find_fsidzero_export(rqstp);
2083 	if (IS_ERR(exp_ps))
2084 		return nfserrno(PTR_ERR(exp_ps));
2085 	res = nfsd4_encode_path(xdr, &exp_ps->ex_path, path);
2086 	exp_put(exp_ps);
2087 	return res;
2088 }
2089 
2090 /*
2091  *  encode a fs_locations structure
2092  */
2093 static __be32 nfsd4_encode_fs_locations(struct xdr_stream *xdr,
2094 			struct svc_rqst *rqstp, struct svc_export *exp)
2095 {
2096 	__be32 status;
2097 	int i;
2098 	__be32 *p;
2099 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
2100 
2101 	status = nfsd4_encode_fsloc_fsroot(xdr, rqstp, &exp->ex_path);
2102 	if (status)
2103 		return status;
2104 	p = xdr_reserve_space(xdr, 4);
2105 	if (!p)
2106 		return nfserr_resource;
2107 	*p++ = cpu_to_be32(fslocs->locations_count);
2108 	for (i=0; i<fslocs->locations_count; i++) {
2109 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
2110 		if (status)
2111 			return status;
2112 	}
2113 	return 0;
2114 }
2115 
2116 static u32 nfs4_file_type(umode_t mode)
2117 {
2118 	switch (mode & S_IFMT) {
2119 	case S_IFIFO:	return NF4FIFO;
2120 	case S_IFCHR:	return NF4CHR;
2121 	case S_IFDIR:	return NF4DIR;
2122 	case S_IFBLK:	return NF4BLK;
2123 	case S_IFLNK:	return NF4LNK;
2124 	case S_IFREG:	return NF4REG;
2125 	case S_IFSOCK:	return NF4SOCK;
2126 	default:	return NF4BAD;
2127 	};
2128 }
2129 
2130 static inline __be32
2131 nfsd4_encode_aclname(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2132 		     struct nfs4_ace *ace)
2133 {
2134 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
2135 		return nfs4_acl_write_who(xdr, ace->whotype);
2136 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
2137 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
2138 	else
2139 		return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
2140 }
2141 
2142 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
2143 			      FATTR4_WORD0_RDATTR_ERROR)
2144 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2145 
2146 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2147 static inline __be32
2148 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2149 			    void *context, int len)
2150 {
2151 	__be32 *p;
2152 
2153 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2154 	if (!p)
2155 		return nfserr_resource;
2156 
2157 	/*
2158 	 * For now we use a 0 here to indicate the null translation; in
2159 	 * the future we may place a call to translation code here.
2160 	 */
2161 	*p++ = cpu_to_be32(0); /* lfs */
2162 	*p++ = cpu_to_be32(0); /* pi */
2163 	p = xdr_encode_opaque(p, context, len);
2164 	return 0;
2165 }
2166 #else
2167 static inline __be32
2168 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2169 			    void *context, int len)
2170 { return 0; }
2171 #endif
2172 
2173 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *rdattr_err)
2174 {
2175 	/* As per referral draft:  */
2176 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2177 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2178 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2179 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2180 			*rdattr_err = NFSERR_MOVED;
2181 		else
2182 			return nfserr_moved;
2183 	}
2184 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2185 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2186 	return 0;
2187 }
2188 
2189 
2190 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2191 {
2192 	struct path path = exp->ex_path;
2193 	int err;
2194 
2195 	path_get(&path);
2196 	while (follow_up(&path)) {
2197 		if (path.dentry != path.mnt->mnt_root)
2198 			break;
2199 	}
2200 	err = vfs_getattr(&path, stat);
2201 	path_put(&path);
2202 	return err;
2203 }
2204 
2205 /*
2206  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2207  * ourselves.
2208  */
2209 static __be32
2210 nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
2211 		struct svc_export *exp,
2212 		struct dentry *dentry, u32 *bmval,
2213 		struct svc_rqst *rqstp, int ignore_crossmnt)
2214 {
2215 	u32 bmval0 = bmval[0];
2216 	u32 bmval1 = bmval[1];
2217 	u32 bmval2 = bmval[2];
2218 	struct kstat stat;
2219 	struct svc_fh *tempfh = NULL;
2220 	struct kstatfs statfs;
2221 	__be32 *p;
2222 	int starting_len = xdr->buf->len;
2223 	int attrlen_offset;
2224 	__be32 attrlen;
2225 	u32 dummy;
2226 	u64 dummy64;
2227 	u32 rdattr_err = 0;
2228 	__be32 status;
2229 	int err;
2230 	int aclsupport = 0;
2231 	struct nfs4_acl *acl = NULL;
2232 	void *context = NULL;
2233 	int contextlen;
2234 	bool contextsupport = false;
2235 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2236 	u32 minorversion = resp->cstate.minorversion;
2237 	struct path path = {
2238 		.mnt	= exp->ex_path.mnt,
2239 		.dentry	= dentry,
2240 	};
2241 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2242 
2243 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2244 	BUG_ON(bmval0 & ~nfsd_suppattrs0(minorversion));
2245 	BUG_ON(bmval1 & ~nfsd_suppattrs1(minorversion));
2246 	BUG_ON(bmval2 & ~nfsd_suppattrs2(minorversion));
2247 
2248 	if (exp->ex_fslocs.migrated) {
2249 		BUG_ON(bmval[2]);
2250 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &rdattr_err);
2251 		if (status)
2252 			goto out;
2253 	}
2254 
2255 	err = vfs_getattr(&path, &stat);
2256 	if (err)
2257 		goto out_nfserr;
2258 	if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
2259 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
2260 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2261 		       FATTR4_WORD1_SPACE_TOTAL))) {
2262 		err = vfs_statfs(&path, &statfs);
2263 		if (err)
2264 			goto out_nfserr;
2265 	}
2266 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2267 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2268 		status = nfserr_jukebox;
2269 		if (!tempfh)
2270 			goto out;
2271 		fh_init(tempfh, NFS4_FHSIZE);
2272 		status = fh_compose(tempfh, exp, dentry, NULL);
2273 		if (status)
2274 			goto out;
2275 		fhp = tempfh;
2276 	}
2277 	if (bmval0 & (FATTR4_WORD0_ACL | FATTR4_WORD0_ACLSUPPORT
2278 			| FATTR4_WORD0_SUPPORTED_ATTRS)) {
2279 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2280 		aclsupport = (err == 0);
2281 		if (bmval0 & FATTR4_WORD0_ACL) {
2282 			if (err == -EOPNOTSUPP)
2283 				bmval0 &= ~FATTR4_WORD0_ACL;
2284 			else if (err == -EINVAL) {
2285 				status = nfserr_attrnotsupp;
2286 				goto out;
2287 			} else if (err != 0)
2288 				goto out_nfserr;
2289 		}
2290 	}
2291 
2292 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2293 	if ((bmval[2] & FATTR4_WORD2_SECURITY_LABEL) ||
2294 			bmval[0] & FATTR4_WORD0_SUPPORTED_ATTRS) {
2295 		err = security_inode_getsecctx(d_inode(dentry),
2296 						&context, &contextlen);
2297 		contextsupport = (err == 0);
2298 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2299 			if (err == -EOPNOTSUPP)
2300 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2301 			else if (err)
2302 				goto out_nfserr;
2303 		}
2304 	}
2305 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2306 
2307 	if (bmval2) {
2308 		p = xdr_reserve_space(xdr, 16);
2309 		if (!p)
2310 			goto out_resource;
2311 		*p++ = cpu_to_be32(3);
2312 		*p++ = cpu_to_be32(bmval0);
2313 		*p++ = cpu_to_be32(bmval1);
2314 		*p++ = cpu_to_be32(bmval2);
2315 	} else if (bmval1) {
2316 		p = xdr_reserve_space(xdr, 12);
2317 		if (!p)
2318 			goto out_resource;
2319 		*p++ = cpu_to_be32(2);
2320 		*p++ = cpu_to_be32(bmval0);
2321 		*p++ = cpu_to_be32(bmval1);
2322 	} else {
2323 		p = xdr_reserve_space(xdr, 8);
2324 		if (!p)
2325 			goto out_resource;
2326 		*p++ = cpu_to_be32(1);
2327 		*p++ = cpu_to_be32(bmval0);
2328 	}
2329 
2330 	attrlen_offset = xdr->buf->len;
2331 	p = xdr_reserve_space(xdr, 4);
2332 	if (!p)
2333 		goto out_resource;
2334 	p++;                /* to be backfilled later */
2335 
2336 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2337 		u32 word0 = nfsd_suppattrs0(minorversion);
2338 		u32 word1 = nfsd_suppattrs1(minorversion);
2339 		u32 word2 = nfsd_suppattrs2(minorversion);
2340 
2341 		if (!aclsupport)
2342 			word0 &= ~FATTR4_WORD0_ACL;
2343 		if (!contextsupport)
2344 			word2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2345 		if (!word2) {
2346 			p = xdr_reserve_space(xdr, 12);
2347 			if (!p)
2348 				goto out_resource;
2349 			*p++ = cpu_to_be32(2);
2350 			*p++ = cpu_to_be32(word0);
2351 			*p++ = cpu_to_be32(word1);
2352 		} else {
2353 			p = xdr_reserve_space(xdr, 16);
2354 			if (!p)
2355 				goto out_resource;
2356 			*p++ = cpu_to_be32(3);
2357 			*p++ = cpu_to_be32(word0);
2358 			*p++ = cpu_to_be32(word1);
2359 			*p++ = cpu_to_be32(word2);
2360 		}
2361 	}
2362 	if (bmval0 & FATTR4_WORD0_TYPE) {
2363 		p = xdr_reserve_space(xdr, 4);
2364 		if (!p)
2365 			goto out_resource;
2366 		dummy = nfs4_file_type(stat.mode);
2367 		if (dummy == NF4BAD) {
2368 			status = nfserr_serverfault;
2369 			goto out;
2370 		}
2371 		*p++ = cpu_to_be32(dummy);
2372 	}
2373 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2374 		p = xdr_reserve_space(xdr, 4);
2375 		if (!p)
2376 			goto out_resource;
2377 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2378 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT);
2379 		else
2380 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT|
2381 						NFS4_FH_VOL_RENAME);
2382 	}
2383 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2384 		p = xdr_reserve_space(xdr, 8);
2385 		if (!p)
2386 			goto out_resource;
2387 		p = encode_change(p, &stat, d_inode(dentry));
2388 	}
2389 	if (bmval0 & FATTR4_WORD0_SIZE) {
2390 		p = xdr_reserve_space(xdr, 8);
2391 		if (!p)
2392 			goto out_resource;
2393 		p = xdr_encode_hyper(p, stat.size);
2394 	}
2395 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2396 		p = xdr_reserve_space(xdr, 4);
2397 		if (!p)
2398 			goto out_resource;
2399 		*p++ = cpu_to_be32(1);
2400 	}
2401 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2402 		p = xdr_reserve_space(xdr, 4);
2403 		if (!p)
2404 			goto out_resource;
2405 		*p++ = cpu_to_be32(1);
2406 	}
2407 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2408 		p = xdr_reserve_space(xdr, 4);
2409 		if (!p)
2410 			goto out_resource;
2411 		*p++ = cpu_to_be32(0);
2412 	}
2413 	if (bmval0 & FATTR4_WORD0_FSID) {
2414 		p = xdr_reserve_space(xdr, 16);
2415 		if (!p)
2416 			goto out_resource;
2417 		if (exp->ex_fslocs.migrated) {
2418 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
2419 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
2420 		} else switch(fsid_source(fhp)) {
2421 		case FSIDSOURCE_FSID:
2422 			p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
2423 			p = xdr_encode_hyper(p, (u64)0);
2424 			break;
2425 		case FSIDSOURCE_DEV:
2426 			*p++ = cpu_to_be32(0);
2427 			*p++ = cpu_to_be32(MAJOR(stat.dev));
2428 			*p++ = cpu_to_be32(0);
2429 			*p++ = cpu_to_be32(MINOR(stat.dev));
2430 			break;
2431 		case FSIDSOURCE_UUID:
2432 			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
2433 								EX_UUID_LEN);
2434 			break;
2435 		}
2436 	}
2437 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2438 		p = xdr_reserve_space(xdr, 4);
2439 		if (!p)
2440 			goto out_resource;
2441 		*p++ = cpu_to_be32(0);
2442 	}
2443 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2444 		p = xdr_reserve_space(xdr, 4);
2445 		if (!p)
2446 			goto out_resource;
2447 		*p++ = cpu_to_be32(nn->nfsd4_lease);
2448 	}
2449 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2450 		p = xdr_reserve_space(xdr, 4);
2451 		if (!p)
2452 			goto out_resource;
2453 		*p++ = cpu_to_be32(rdattr_err);
2454 	}
2455 	if (bmval0 & FATTR4_WORD0_ACL) {
2456 		struct nfs4_ace *ace;
2457 
2458 		if (acl == NULL) {
2459 			p = xdr_reserve_space(xdr, 4);
2460 			if (!p)
2461 				goto out_resource;
2462 
2463 			*p++ = cpu_to_be32(0);
2464 			goto out_acl;
2465 		}
2466 		p = xdr_reserve_space(xdr, 4);
2467 		if (!p)
2468 			goto out_resource;
2469 		*p++ = cpu_to_be32(acl->naces);
2470 
2471 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2472 			p = xdr_reserve_space(xdr, 4*3);
2473 			if (!p)
2474 				goto out_resource;
2475 			*p++ = cpu_to_be32(ace->type);
2476 			*p++ = cpu_to_be32(ace->flag);
2477 			*p++ = cpu_to_be32(ace->access_mask &
2478 							NFS4_ACE_MASK_ALL);
2479 			status = nfsd4_encode_aclname(xdr, rqstp, ace);
2480 			if (status)
2481 				goto out;
2482 		}
2483 	}
2484 out_acl:
2485 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2486 		p = xdr_reserve_space(xdr, 4);
2487 		if (!p)
2488 			goto out_resource;
2489 		*p++ = cpu_to_be32(aclsupport ?
2490 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2491 	}
2492 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2493 		p = xdr_reserve_space(xdr, 4);
2494 		if (!p)
2495 			goto out_resource;
2496 		*p++ = cpu_to_be32(1);
2497 	}
2498 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2499 		p = xdr_reserve_space(xdr, 4);
2500 		if (!p)
2501 			goto out_resource;
2502 		*p++ = cpu_to_be32(0);
2503 	}
2504 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2505 		p = xdr_reserve_space(xdr, 4);
2506 		if (!p)
2507 			goto out_resource;
2508 		*p++ = cpu_to_be32(1);
2509 	}
2510 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2511 		p = xdr_reserve_space(xdr, 4);
2512 		if (!p)
2513 			goto out_resource;
2514 		*p++ = cpu_to_be32(1);
2515 	}
2516 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2517 		p = xdr_reserve_space(xdr, fhp->fh_handle.fh_size + 4);
2518 		if (!p)
2519 			goto out_resource;
2520 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base,
2521 					fhp->fh_handle.fh_size);
2522 	}
2523 	if (bmval0 & FATTR4_WORD0_FILEID) {
2524 		p = xdr_reserve_space(xdr, 8);
2525 		if (!p)
2526 			goto out_resource;
2527 		p = xdr_encode_hyper(p, stat.ino);
2528 	}
2529 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2530 		p = xdr_reserve_space(xdr, 8);
2531 		if (!p)
2532 			goto out_resource;
2533 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2534 	}
2535 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2536 		p = xdr_reserve_space(xdr, 8);
2537 		if (!p)
2538 			goto out_resource;
2539 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2540 	}
2541 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2542 		p = xdr_reserve_space(xdr, 8);
2543 		if (!p)
2544 			goto out_resource;
2545 		p = xdr_encode_hyper(p, (u64) statfs.f_files);
2546 	}
2547 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2548 		status = nfsd4_encode_fs_locations(xdr, rqstp, exp);
2549 		if (status)
2550 			goto out;
2551 	}
2552 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2553 		p = xdr_reserve_space(xdr, 4);
2554 		if (!p)
2555 			goto out_resource;
2556 		*p++ = cpu_to_be32(1);
2557 	}
2558 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2559 		p = xdr_reserve_space(xdr, 8);
2560 		if (!p)
2561 			goto out_resource;
2562 		p = xdr_encode_hyper(p, exp->ex_path.mnt->mnt_sb->s_maxbytes);
2563 	}
2564 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2565 		p = xdr_reserve_space(xdr, 4);
2566 		if (!p)
2567 			goto out_resource;
2568 		*p++ = cpu_to_be32(255);
2569 	}
2570 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2571 		p = xdr_reserve_space(xdr, 4);
2572 		if (!p)
2573 			goto out_resource;
2574 		*p++ = cpu_to_be32(statfs.f_namelen);
2575 	}
2576 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2577 		p = xdr_reserve_space(xdr, 8);
2578 		if (!p)
2579 			goto out_resource;
2580 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2581 	}
2582 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2583 		p = xdr_reserve_space(xdr, 8);
2584 		if (!p)
2585 			goto out_resource;
2586 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2587 	}
2588 	if (bmval1 & FATTR4_WORD1_MODE) {
2589 		p = xdr_reserve_space(xdr, 4);
2590 		if (!p)
2591 			goto out_resource;
2592 		*p++ = cpu_to_be32(stat.mode & S_IALLUGO);
2593 	}
2594 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2595 		p = xdr_reserve_space(xdr, 4);
2596 		if (!p)
2597 			goto out_resource;
2598 		*p++ = cpu_to_be32(1);
2599 	}
2600 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2601 		p = xdr_reserve_space(xdr, 4);
2602 		if (!p)
2603 			goto out_resource;
2604 		*p++ = cpu_to_be32(stat.nlink);
2605 	}
2606 	if (bmval1 & FATTR4_WORD1_OWNER) {
2607 		status = nfsd4_encode_user(xdr, rqstp, stat.uid);
2608 		if (status)
2609 			goto out;
2610 	}
2611 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2612 		status = nfsd4_encode_group(xdr, rqstp, stat.gid);
2613 		if (status)
2614 			goto out;
2615 	}
2616 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2617 		p = xdr_reserve_space(xdr, 8);
2618 		if (!p)
2619 			goto out_resource;
2620 		*p++ = cpu_to_be32((u32) MAJOR(stat.rdev));
2621 		*p++ = cpu_to_be32((u32) MINOR(stat.rdev));
2622 	}
2623 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2624 		p = xdr_reserve_space(xdr, 8);
2625 		if (!p)
2626 			goto out_resource;
2627 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2628 		p = xdr_encode_hyper(p, dummy64);
2629 	}
2630 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2631 		p = xdr_reserve_space(xdr, 8);
2632 		if (!p)
2633 			goto out_resource;
2634 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2635 		p = xdr_encode_hyper(p, dummy64);
2636 	}
2637 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2638 		p = xdr_reserve_space(xdr, 8);
2639 		if (!p)
2640 			goto out_resource;
2641 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2642 		p = xdr_encode_hyper(p, dummy64);
2643 	}
2644 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2645 		p = xdr_reserve_space(xdr, 8);
2646 		if (!p)
2647 			goto out_resource;
2648 		dummy64 = (u64)stat.blocks << 9;
2649 		p = xdr_encode_hyper(p, dummy64);
2650 	}
2651 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2652 		p = xdr_reserve_space(xdr, 12);
2653 		if (!p)
2654 			goto out_resource;
2655 		p = xdr_encode_hyper(p, (s64)stat.atime.tv_sec);
2656 		*p++ = cpu_to_be32(stat.atime.tv_nsec);
2657 	}
2658 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2659 		p = xdr_reserve_space(xdr, 12);
2660 		if (!p)
2661 			goto out_resource;
2662 		*p++ = cpu_to_be32(0);
2663 		*p++ = cpu_to_be32(1);
2664 		*p++ = cpu_to_be32(0);
2665 	}
2666 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2667 		p = xdr_reserve_space(xdr, 12);
2668 		if (!p)
2669 			goto out_resource;
2670 		p = xdr_encode_hyper(p, (s64)stat.ctime.tv_sec);
2671 		*p++ = cpu_to_be32(stat.ctime.tv_nsec);
2672 	}
2673 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2674 		p = xdr_reserve_space(xdr, 12);
2675 		if (!p)
2676 			goto out_resource;
2677 		p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
2678 		*p++ = cpu_to_be32(stat.mtime.tv_nsec);
2679 	}
2680 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2681 		p = xdr_reserve_space(xdr, 8);
2682 		if (!p)
2683                 	goto out_resource;
2684 		/*
2685 		 * Get parent's attributes if not ignoring crossmount
2686 		 * and this is the root of a cross-mounted filesystem.
2687 		 */
2688 		if (ignore_crossmnt == 0 &&
2689 		    dentry == exp->ex_path.mnt->mnt_root)
2690 			get_parent_attributes(exp, &stat);
2691 		p = xdr_encode_hyper(p, stat.ino);
2692 	}
2693 #ifdef CONFIG_NFSD_PNFS
2694 	if ((bmval1 & FATTR4_WORD1_FS_LAYOUT_TYPES) ||
2695 	    (bmval2 & FATTR4_WORD2_LAYOUT_TYPES)) {
2696 		if (exp->ex_layout_type) {
2697 			p = xdr_reserve_space(xdr, 8);
2698 			if (!p)
2699 				goto out_resource;
2700 			*p++ = cpu_to_be32(1);
2701 			*p++ = cpu_to_be32(exp->ex_layout_type);
2702 		} else {
2703 			p = xdr_reserve_space(xdr, 4);
2704 			if (!p)
2705 				goto out_resource;
2706 			*p++ = cpu_to_be32(0);
2707 		}
2708 	}
2709 
2710 	if (bmval2 & FATTR4_WORD2_LAYOUT_BLKSIZE) {
2711 		p = xdr_reserve_space(xdr, 4);
2712 		if (!p)
2713 			goto out_resource;
2714 		*p++ = cpu_to_be32(stat.blksize);
2715 	}
2716 #endif /* CONFIG_NFSD_PNFS */
2717 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2718 		status = nfsd4_encode_security_label(xdr, rqstp, context,
2719 								contextlen);
2720 		if (status)
2721 			goto out;
2722 	}
2723 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2724 		p = xdr_reserve_space(xdr, 16);
2725 		if (!p)
2726 			goto out_resource;
2727 		*p++ = cpu_to_be32(3);
2728 		*p++ = cpu_to_be32(NFSD_SUPPATTR_EXCLCREAT_WORD0);
2729 		*p++ = cpu_to_be32(NFSD_SUPPATTR_EXCLCREAT_WORD1);
2730 		*p++ = cpu_to_be32(NFSD_SUPPATTR_EXCLCREAT_WORD2);
2731 	}
2732 
2733 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
2734 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
2735 	status = nfs_ok;
2736 
2737 out:
2738 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2739 	if (context)
2740 		security_release_secctx(context, contextlen);
2741 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2742 	kfree(acl);
2743 	if (tempfh) {
2744 		fh_put(tempfh);
2745 		kfree(tempfh);
2746 	}
2747 	if (status)
2748 		xdr_truncate_encode(xdr, starting_len);
2749 	return status;
2750 out_nfserr:
2751 	status = nfserrno(err);
2752 	goto out;
2753 out_resource:
2754 	status = nfserr_resource;
2755 	goto out;
2756 }
2757 
2758 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
2759 				struct xdr_buf *buf, __be32 *p, int bytes)
2760 {
2761 	xdr->scratch.iov_len = 0;
2762 	memset(buf, 0, sizeof(struct xdr_buf));
2763 	buf->head[0].iov_base = p;
2764 	buf->head[0].iov_len = 0;
2765 	buf->len = 0;
2766 	xdr->buf = buf;
2767 	xdr->iov = buf->head;
2768 	xdr->p = p;
2769 	xdr->end = (void *)p + bytes;
2770 	buf->buflen = bytes;
2771 }
2772 
2773 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
2774 			struct svc_fh *fhp, struct svc_export *exp,
2775 			struct dentry *dentry, u32 *bmval,
2776 			struct svc_rqst *rqstp, int ignore_crossmnt)
2777 {
2778 	struct xdr_buf dummy;
2779 	struct xdr_stream xdr;
2780 	__be32 ret;
2781 
2782 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
2783 	ret = nfsd4_encode_fattr(&xdr, fhp, exp, dentry, bmval, rqstp,
2784 							ignore_crossmnt);
2785 	*p = xdr.p;
2786 	return ret;
2787 }
2788 
2789 static inline int attributes_need_mount(u32 *bmval)
2790 {
2791 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2792 		return 1;
2793 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2794 		return 1;
2795 	return 0;
2796 }
2797 
2798 static __be32
2799 nfsd4_encode_dirent_fattr(struct xdr_stream *xdr, struct nfsd4_readdir *cd,
2800 			const char *name, int namlen)
2801 {
2802 	struct svc_export *exp = cd->rd_fhp->fh_export;
2803 	struct dentry *dentry;
2804 	__be32 nfserr;
2805 	int ignore_crossmnt = 0;
2806 
2807 	dentry = lookup_one_len(name, cd->rd_fhp->fh_dentry, namlen);
2808 	if (IS_ERR(dentry))
2809 		return nfserrno(PTR_ERR(dentry));
2810 	if (d_really_is_negative(dentry)) {
2811 		/*
2812 		 * nfsd_buffered_readdir drops the i_mutex between
2813 		 * readdir and calling this callback, leaving a window
2814 		 * where this directory entry could have gone away.
2815 		 */
2816 		dput(dentry);
2817 		return nfserr_noent;
2818 	}
2819 
2820 	exp_get(exp);
2821 	/*
2822 	 * In the case of a mountpoint, the client may be asking for
2823 	 * attributes that are only properties of the underlying filesystem
2824 	 * as opposed to the cross-mounted file system. In such a case,
2825 	 * we will not follow the cross mount and will fill the attribtutes
2826 	 * directly from the mountpoint dentry.
2827 	 */
2828 	if (nfsd_mountpoint(dentry, exp)) {
2829 		int err;
2830 
2831 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
2832 				&& !attributes_need_mount(cd->rd_bmval)) {
2833 			ignore_crossmnt = 1;
2834 			goto out_encode;
2835 		}
2836 		/*
2837 		 * Why the heck aren't we just using nfsd_lookup??
2838 		 * Different "."/".." handling?  Something else?
2839 		 * At least, add a comment here to explain....
2840 		 */
2841 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
2842 		if (err) {
2843 			nfserr = nfserrno(err);
2844 			goto out_put;
2845 		}
2846 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
2847 		if (nfserr)
2848 			goto out_put;
2849 
2850 	}
2851 out_encode:
2852 	nfserr = nfsd4_encode_fattr(xdr, NULL, exp, dentry, cd->rd_bmval,
2853 					cd->rd_rqstp, ignore_crossmnt);
2854 out_put:
2855 	dput(dentry);
2856 	exp_put(exp);
2857 	return nfserr;
2858 }
2859 
2860 static __be32 *
2861 nfsd4_encode_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
2862 {
2863 	__be32 *p;
2864 
2865 	p = xdr_reserve_space(xdr, 20);
2866 	if (!p)
2867 		return NULL;
2868 	*p++ = htonl(2);
2869 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
2870 	*p++ = htonl(0);			 /* bmval1 */
2871 
2872 	*p++ = htonl(4);     /* attribute length */
2873 	*p++ = nfserr;       /* no htonl */
2874 	return p;
2875 }
2876 
2877 static int
2878 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
2879 		    loff_t offset, u64 ino, unsigned int d_type)
2880 {
2881 	struct readdir_cd *ccd = ccdv;
2882 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
2883 	struct xdr_stream *xdr = cd->xdr;
2884 	int start_offset = xdr->buf->len;
2885 	int cookie_offset;
2886 	u32 name_and_cookie;
2887 	int entry_bytes;
2888 	__be32 nfserr = nfserr_toosmall;
2889 	__be64 wire_offset;
2890 	__be32 *p;
2891 
2892 	/* In nfsv4, "." and ".." never make it onto the wire.. */
2893 	if (name && isdotent(name, namlen)) {
2894 		cd->common.err = nfs_ok;
2895 		return 0;
2896 	}
2897 
2898 	if (cd->cookie_offset) {
2899 		wire_offset = cpu_to_be64(offset);
2900 		write_bytes_to_xdr_buf(xdr->buf, cd->cookie_offset,
2901 							&wire_offset, 8);
2902 	}
2903 
2904 	p = xdr_reserve_space(xdr, 4);
2905 	if (!p)
2906 		goto fail;
2907 	*p++ = xdr_one;                             /* mark entry present */
2908 	cookie_offset = xdr->buf->len;
2909 	p = xdr_reserve_space(xdr, 3*4 + namlen);
2910 	if (!p)
2911 		goto fail;
2912 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
2913 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
2914 
2915 	nfserr = nfsd4_encode_dirent_fattr(xdr, cd, name, namlen);
2916 	switch (nfserr) {
2917 	case nfs_ok:
2918 		break;
2919 	case nfserr_resource:
2920 		nfserr = nfserr_toosmall;
2921 		goto fail;
2922 	case nfserr_noent:
2923 		xdr_truncate_encode(xdr, start_offset);
2924 		goto skip_entry;
2925 	default:
2926 		/*
2927 		 * If the client requested the RDATTR_ERROR attribute,
2928 		 * we stuff the error code into this attribute
2929 		 * and continue.  If this attribute was not requested,
2930 		 * then in accordance with the spec, we fail the
2931 		 * entire READDIR operation(!)
2932 		 */
2933 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
2934 			goto fail;
2935 		p = nfsd4_encode_rdattr_error(xdr, nfserr);
2936 		if (p == NULL) {
2937 			nfserr = nfserr_toosmall;
2938 			goto fail;
2939 		}
2940 	}
2941 	nfserr = nfserr_toosmall;
2942 	entry_bytes = xdr->buf->len - start_offset;
2943 	if (entry_bytes > cd->rd_maxcount)
2944 		goto fail;
2945 	cd->rd_maxcount -= entry_bytes;
2946 	/*
2947 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so
2948 	 * let's always let through the first entry, at least:
2949 	 */
2950 	if (!cd->rd_dircount)
2951 		goto fail;
2952 	name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8;
2953 	if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
2954 		goto fail;
2955 	cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
2956 
2957 	cd->cookie_offset = cookie_offset;
2958 skip_entry:
2959 	cd->common.err = nfs_ok;
2960 	return 0;
2961 fail:
2962 	xdr_truncate_encode(xdr, start_offset);
2963 	cd->common.err = nfserr;
2964 	return -EINVAL;
2965 }
2966 
2967 static __be32
2968 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
2969 {
2970 	__be32 *p;
2971 
2972 	p = xdr_reserve_space(xdr, sizeof(stateid_t));
2973 	if (!p)
2974 		return nfserr_resource;
2975 	*p++ = cpu_to_be32(sid->si_generation);
2976 	p = xdr_encode_opaque_fixed(p, &sid->si_opaque,
2977 					sizeof(stateid_opaque_t));
2978 	return 0;
2979 }
2980 
2981 static __be32
2982 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
2983 {
2984 	struct xdr_stream *xdr = &resp->xdr;
2985 	__be32 *p;
2986 
2987 	if (!nfserr) {
2988 		p = xdr_reserve_space(xdr, 8);
2989 		if (!p)
2990 			return nfserr_resource;
2991 		*p++ = cpu_to_be32(access->ac_supported);
2992 		*p++ = cpu_to_be32(access->ac_resp_access);
2993 	}
2994 	return nfserr;
2995 }
2996 
2997 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
2998 {
2999 	struct xdr_stream *xdr = &resp->xdr;
3000 	__be32 *p;
3001 
3002 	if (!nfserr) {
3003 		p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 8);
3004 		if (!p)
3005 			return nfserr_resource;
3006 		p = xdr_encode_opaque_fixed(p, bcts->sessionid.data,
3007 						NFS4_MAX_SESSIONID_LEN);
3008 		*p++ = cpu_to_be32(bcts->dir);
3009 		/* Sorry, we do not yet support RDMA over 4.1: */
3010 		*p++ = cpu_to_be32(0);
3011 	}
3012 	return nfserr;
3013 }
3014 
3015 static __be32
3016 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
3017 {
3018 	struct xdr_stream *xdr = &resp->xdr;
3019 
3020 	if (!nfserr)
3021 		nfserr = nfsd4_encode_stateid(xdr, &close->cl_stateid);
3022 
3023 	return nfserr;
3024 }
3025 
3026 
3027 static __be32
3028 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
3029 {
3030 	struct xdr_stream *xdr = &resp->xdr;
3031 	__be32 *p;
3032 
3033 	if (!nfserr) {
3034 		p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3035 		if (!p)
3036 			return nfserr_resource;
3037 		p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
3038 						NFS4_VERIFIER_SIZE);
3039 	}
3040 	return nfserr;
3041 }
3042 
3043 static __be32
3044 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
3045 {
3046 	struct xdr_stream *xdr = &resp->xdr;
3047 	__be32 *p;
3048 
3049 	if (!nfserr) {
3050 		p = xdr_reserve_space(xdr, 32);
3051 		if (!p)
3052 			return nfserr_resource;
3053 		p = encode_cinfo(p, &create->cr_cinfo);
3054 		*p++ = cpu_to_be32(2);
3055 		*p++ = cpu_to_be32(create->cr_bmval[0]);
3056 		*p++ = cpu_to_be32(create->cr_bmval[1]);
3057 	}
3058 	return nfserr;
3059 }
3060 
3061 static __be32
3062 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
3063 {
3064 	struct svc_fh *fhp = getattr->ga_fhp;
3065 	struct xdr_stream *xdr = &resp->xdr;
3066 
3067 	if (nfserr)
3068 		return nfserr;
3069 
3070 	nfserr = nfsd4_encode_fattr(xdr, fhp, fhp->fh_export, fhp->fh_dentry,
3071 				    getattr->ga_bmval,
3072 				    resp->rqstp, 0);
3073 	return nfserr;
3074 }
3075 
3076 static __be32
3077 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
3078 {
3079 	struct xdr_stream *xdr = &resp->xdr;
3080 	struct svc_fh *fhp = *fhpp;
3081 	unsigned int len;
3082 	__be32 *p;
3083 
3084 	if (!nfserr) {
3085 		len = fhp->fh_handle.fh_size;
3086 		p = xdr_reserve_space(xdr, len + 4);
3087 		if (!p)
3088 			return nfserr_resource;
3089 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base, len);
3090 	}
3091 	return nfserr;
3092 }
3093 
3094 /*
3095 * Including all fields other than the name, a LOCK4denied structure requires
3096 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
3097 */
3098 static __be32
3099 nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld)
3100 {
3101 	struct xdr_netobj *conf = &ld->ld_owner;
3102 	__be32 *p;
3103 
3104 again:
3105 	p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len));
3106 	if (!p) {
3107 		/*
3108 		 * Don't fail to return the result just because we can't
3109 		 * return the conflicting open:
3110 		 */
3111 		if (conf->len) {
3112 			kfree(conf->data);
3113 			conf->len = 0;
3114 			conf->data = NULL;
3115 			goto again;
3116 		}
3117 		return nfserr_resource;
3118 	}
3119 	p = xdr_encode_hyper(p, ld->ld_start);
3120 	p = xdr_encode_hyper(p, ld->ld_length);
3121 	*p++ = cpu_to_be32(ld->ld_type);
3122 	if (conf->len) {
3123 		p = xdr_encode_opaque_fixed(p, &ld->ld_clientid, 8);
3124 		p = xdr_encode_opaque(p, conf->data, conf->len);
3125 		kfree(conf->data);
3126 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
3127 		p = xdr_encode_hyper(p, (u64)0); /* clientid */
3128 		*p++ = cpu_to_be32(0); /* length of owner name */
3129 	}
3130 	return nfserr_denied;
3131 }
3132 
3133 static __be32
3134 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
3135 {
3136 	struct xdr_stream *xdr = &resp->xdr;
3137 
3138 	if (!nfserr)
3139 		nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid);
3140 	else if (nfserr == nfserr_denied)
3141 		nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied);
3142 
3143 	return nfserr;
3144 }
3145 
3146 static __be32
3147 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
3148 {
3149 	struct xdr_stream *xdr = &resp->xdr;
3150 
3151 	if (nfserr == nfserr_denied)
3152 		nfsd4_encode_lock_denied(xdr, &lockt->lt_denied);
3153 	return nfserr;
3154 }
3155 
3156 static __be32
3157 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
3158 {
3159 	struct xdr_stream *xdr = &resp->xdr;
3160 
3161 	if (!nfserr)
3162 		nfserr = nfsd4_encode_stateid(xdr, &locku->lu_stateid);
3163 
3164 	return nfserr;
3165 }
3166 
3167 
3168 static __be32
3169 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
3170 {
3171 	struct xdr_stream *xdr = &resp->xdr;
3172 	__be32 *p;
3173 
3174 	if (!nfserr) {
3175 		p = xdr_reserve_space(xdr, 20);
3176 		if (!p)
3177 			return nfserr_resource;
3178 		p = encode_cinfo(p, &link->li_cinfo);
3179 	}
3180 	return nfserr;
3181 }
3182 
3183 
3184 static __be32
3185 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
3186 {
3187 	struct xdr_stream *xdr = &resp->xdr;
3188 	__be32 *p;
3189 
3190 	if (nfserr)
3191 		goto out;
3192 
3193 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
3194 	if (nfserr)
3195 		goto out;
3196 	p = xdr_reserve_space(xdr, 40);
3197 	if (!p)
3198 		return nfserr_resource;
3199 	p = encode_cinfo(p, &open->op_cinfo);
3200 	*p++ = cpu_to_be32(open->op_rflags);
3201 	*p++ = cpu_to_be32(2);
3202 	*p++ = cpu_to_be32(open->op_bmval[0]);
3203 	*p++ = cpu_to_be32(open->op_bmval[1]);
3204 	*p++ = cpu_to_be32(open->op_delegate_type);
3205 
3206 	switch (open->op_delegate_type) {
3207 	case NFS4_OPEN_DELEGATE_NONE:
3208 		break;
3209 	case NFS4_OPEN_DELEGATE_READ:
3210 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3211 		if (nfserr)
3212 			return nfserr;
3213 		p = xdr_reserve_space(xdr, 20);
3214 		if (!p)
3215 			return nfserr_resource;
3216 		*p++ = cpu_to_be32(open->op_recall);
3217 
3218 		/*
3219 		 * TODO: ACE's in delegations
3220 		 */
3221 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3222 		*p++ = cpu_to_be32(0);
3223 		*p++ = cpu_to_be32(0);
3224 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3225 		break;
3226 	case NFS4_OPEN_DELEGATE_WRITE:
3227 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3228 		if (nfserr)
3229 			return nfserr;
3230 		p = xdr_reserve_space(xdr, 32);
3231 		if (!p)
3232 			return nfserr_resource;
3233 		*p++ = cpu_to_be32(0);
3234 
3235 		/*
3236 		 * TODO: space_limit's in delegations
3237 		 */
3238 		*p++ = cpu_to_be32(NFS4_LIMIT_SIZE);
3239 		*p++ = cpu_to_be32(~(u32)0);
3240 		*p++ = cpu_to_be32(~(u32)0);
3241 
3242 		/*
3243 		 * TODO: ACE's in delegations
3244 		 */
3245 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3246 		*p++ = cpu_to_be32(0);
3247 		*p++ = cpu_to_be32(0);
3248 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3249 		break;
3250 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
3251 		switch (open->op_why_no_deleg) {
3252 		case WND4_CONTENTION:
3253 		case WND4_RESOURCE:
3254 			p = xdr_reserve_space(xdr, 8);
3255 			if (!p)
3256 				return nfserr_resource;
3257 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3258 			/* deleg signaling not supported yet: */
3259 			*p++ = cpu_to_be32(0);
3260 			break;
3261 		default:
3262 			p = xdr_reserve_space(xdr, 4);
3263 			if (!p)
3264 				return nfserr_resource;
3265 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3266 		}
3267 		break;
3268 	default:
3269 		BUG();
3270 	}
3271 	/* XXX save filehandle here */
3272 out:
3273 	return nfserr;
3274 }
3275 
3276 static __be32
3277 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
3278 {
3279 	struct xdr_stream *xdr = &resp->xdr;
3280 
3281 	if (!nfserr)
3282 		nfserr = nfsd4_encode_stateid(xdr, &oc->oc_resp_stateid);
3283 
3284 	return nfserr;
3285 }
3286 
3287 static __be32
3288 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
3289 {
3290 	struct xdr_stream *xdr = &resp->xdr;
3291 
3292 	if (!nfserr)
3293 		nfserr = nfsd4_encode_stateid(xdr, &od->od_stateid);
3294 
3295 	return nfserr;
3296 }
3297 
3298 static __be32 nfsd4_encode_splice_read(
3299 				struct nfsd4_compoundres *resp,
3300 				struct nfsd4_read *read,
3301 				struct file *file, unsigned long maxcount)
3302 {
3303 	struct xdr_stream *xdr = &resp->xdr;
3304 	struct xdr_buf *buf = xdr->buf;
3305 	u32 eof;
3306 	int space_left;
3307 	__be32 nfserr;
3308 	__be32 *p = xdr->p - 2;
3309 
3310 	/* Make sure there will be room for padding if needed */
3311 	if (xdr->end - xdr->p < 1)
3312 		return nfserr_resource;
3313 
3314 	nfserr = nfsd_splice_read(read->rd_rqstp, file,
3315 				  read->rd_offset, &maxcount);
3316 	if (nfserr) {
3317 		/*
3318 		 * nfsd_splice_actor may have already messed with the
3319 		 * page length; reset it so as not to confuse
3320 		 * xdr_truncate_encode:
3321 		 */
3322 		buf->page_len = 0;
3323 		return nfserr;
3324 	}
3325 
3326 	eof = (read->rd_offset + maxcount >=
3327 	       d_inode(read->rd_fhp->fh_dentry)->i_size);
3328 
3329 	*(p++) = htonl(eof);
3330 	*(p++) = htonl(maxcount);
3331 
3332 	buf->page_len = maxcount;
3333 	buf->len += maxcount;
3334 	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
3335 							/ PAGE_SIZE;
3336 
3337 	/* Use rest of head for padding and remaining ops: */
3338 	buf->tail[0].iov_base = xdr->p;
3339 	buf->tail[0].iov_len = 0;
3340 	xdr->iov = buf->tail;
3341 	if (maxcount&3) {
3342 		int pad = 4 - (maxcount&3);
3343 
3344 		*(xdr->p++) = 0;
3345 
3346 		buf->tail[0].iov_base += maxcount&3;
3347 		buf->tail[0].iov_len = pad;
3348 		buf->len += pad;
3349 	}
3350 
3351 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
3352 				buf->buflen - buf->len);
3353 	buf->buflen = buf->len + space_left;
3354 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
3355 
3356 	return 0;
3357 }
3358 
3359 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
3360 				 struct nfsd4_read *read,
3361 				 struct file *file, unsigned long maxcount)
3362 {
3363 	struct xdr_stream *xdr = &resp->xdr;
3364 	u32 eof;
3365 	int v;
3366 	int starting_len = xdr->buf->len - 8;
3367 	long len;
3368 	int thislen;
3369 	__be32 nfserr;
3370 	__be32 tmp;
3371 	__be32 *p;
3372 	u32 zzz = 0;
3373 	int pad;
3374 
3375 	len = maxcount;
3376 	v = 0;
3377 
3378 	thislen = min_t(long, len, ((void *)xdr->end - (void *)xdr->p));
3379 	p = xdr_reserve_space(xdr, (thislen+3)&~3);
3380 	WARN_ON_ONCE(!p);
3381 	resp->rqstp->rq_vec[v].iov_base = p;
3382 	resp->rqstp->rq_vec[v].iov_len = thislen;
3383 	v++;
3384 	len -= thislen;
3385 
3386 	while (len) {
3387 		thislen = min_t(long, len, PAGE_SIZE);
3388 		p = xdr_reserve_space(xdr, (thislen+3)&~3);
3389 		WARN_ON_ONCE(!p);
3390 		resp->rqstp->rq_vec[v].iov_base = p;
3391 		resp->rqstp->rq_vec[v].iov_len = thislen;
3392 		v++;
3393 		len -= thislen;
3394 	}
3395 	read->rd_vlen = v;
3396 
3397 	nfserr = nfsd_readv(file, read->rd_offset, resp->rqstp->rq_vec,
3398 			read->rd_vlen, &maxcount);
3399 	if (nfserr)
3400 		return nfserr;
3401 	xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3));
3402 
3403 	eof = (read->rd_offset + maxcount >=
3404 	       d_inode(read->rd_fhp->fh_dentry)->i_size);
3405 
3406 	tmp = htonl(eof);
3407 	write_bytes_to_xdr_buf(xdr->buf, starting_len    , &tmp, 4);
3408 	tmp = htonl(maxcount);
3409 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
3410 
3411 	pad = (maxcount&3) ? 4 - (maxcount&3) : 0;
3412 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 8 + maxcount,
3413 								&zzz, pad);
3414 	return 0;
3415 
3416 }
3417 
3418 static __be32
3419 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
3420 		  struct nfsd4_read *read)
3421 {
3422 	unsigned long maxcount;
3423 	struct xdr_stream *xdr = &resp->xdr;
3424 	struct file *file = read->rd_filp;
3425 	struct svc_fh *fhp = read->rd_fhp;
3426 	int starting_len = xdr->buf->len;
3427 	struct raparms *ra;
3428 	__be32 *p;
3429 	__be32 err;
3430 
3431 	if (nfserr)
3432 		return nfserr;
3433 
3434 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
3435 	if (!p) {
3436 		WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
3437 		return nfserr_resource;
3438 	}
3439 	if (resp->xdr.buf->page_len && test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
3440 		WARN_ON_ONCE(1);
3441 		return nfserr_resource;
3442 	}
3443 	xdr_commit_encode(xdr);
3444 
3445 	maxcount = svc_max_payload(resp->rqstp);
3446 	maxcount = min_t(unsigned long, maxcount, (xdr->buf->buflen - xdr->buf->len));
3447 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
3448 
3449 	if (read->rd_filp)
3450 		err = nfsd_permission(resp->rqstp, fhp->fh_export,
3451 				fhp->fh_dentry,
3452 				NFSD_MAY_READ|NFSD_MAY_OWNER_OVERRIDE);
3453 	else
3454 		err = nfsd_get_tmp_read_open(resp->rqstp, read->rd_fhp,
3455 						&file, &ra);
3456 	if (err)
3457 		goto err_truncate;
3458 
3459 	if (file->f_op->splice_read && test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
3460 		err = nfsd4_encode_splice_read(resp, read, file, maxcount);
3461 	else
3462 		err = nfsd4_encode_readv(resp, read, file, maxcount);
3463 
3464 	if (!read->rd_filp)
3465 		nfsd_put_tmp_read_open(file, ra);
3466 
3467 err_truncate:
3468 	if (err)
3469 		xdr_truncate_encode(xdr, starting_len);
3470 	return err;
3471 }
3472 
3473 static __be32
3474 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3475 {
3476 	int maxcount;
3477 	__be32 wire_count;
3478 	int zero = 0;
3479 	struct xdr_stream *xdr = &resp->xdr;
3480 	int length_offset = xdr->buf->len;
3481 	__be32 *p;
3482 
3483 	if (nfserr)
3484 		return nfserr;
3485 
3486 	p = xdr_reserve_space(xdr, 4);
3487 	if (!p)
3488 		return nfserr_resource;
3489 	maxcount = PAGE_SIZE;
3490 
3491 	p = xdr_reserve_space(xdr, maxcount);
3492 	if (!p)
3493 		return nfserr_resource;
3494 	/*
3495 	 * XXX: By default, the ->readlink() VFS op will truncate symlinks
3496 	 * if they would overflow the buffer.  Is this kosher in NFSv4?  If
3497 	 * not, one easy fix is: if ->readlink() precisely fills the buffer,
3498 	 * assume that truncation occurred, and return NFS4ERR_RESOURCE.
3499 	 */
3500 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
3501 						(char *)p, &maxcount);
3502 	if (nfserr == nfserr_isdir)
3503 		nfserr = nfserr_inval;
3504 	if (nfserr) {
3505 		xdr_truncate_encode(xdr, length_offset);
3506 		return nfserr;
3507 	}
3508 
3509 	wire_count = htonl(maxcount);
3510 	write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
3511 	xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
3512 	if (maxcount & 3)
3513 		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
3514 						&zero, 4 - (maxcount&3));
3515 	return 0;
3516 }
3517 
3518 static __be32
3519 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3520 {
3521 	int maxcount;
3522 	int bytes_left;
3523 	loff_t offset;
3524 	__be64 wire_offset;
3525 	struct xdr_stream *xdr = &resp->xdr;
3526 	int starting_len = xdr->buf->len;
3527 	__be32 *p;
3528 
3529 	if (nfserr)
3530 		return nfserr;
3531 
3532 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3533 	if (!p)
3534 		return nfserr_resource;
3535 
3536 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3537 	*p++ = cpu_to_be32(0);
3538 	*p++ = cpu_to_be32(0);
3539 	resp->xdr.buf->head[0].iov_len = ((char *)resp->xdr.p)
3540 				- (char *)resp->xdr.buf->head[0].iov_base;
3541 
3542 	/*
3543 	 * Number of bytes left for directory entries allowing for the
3544 	 * final 8 bytes of the readdir and a following failed op:
3545 	 */
3546 	bytes_left = xdr->buf->buflen - xdr->buf->len
3547 			- COMPOUND_ERR_SLACK_SPACE - 8;
3548 	if (bytes_left < 0) {
3549 		nfserr = nfserr_resource;
3550 		goto err_no_verf;
3551 	}
3552 	maxcount = min_t(u32, readdir->rd_maxcount, INT_MAX);
3553 	/*
3554 	 * Note the rfc defines rd_maxcount as the size of the
3555 	 * READDIR4resok structure, which includes the verifier above
3556 	 * and the 8 bytes encoded at the end of this function:
3557 	 */
3558 	if (maxcount < 16) {
3559 		nfserr = nfserr_toosmall;
3560 		goto err_no_verf;
3561 	}
3562 	maxcount = min_t(int, maxcount-16, bytes_left);
3563 
3564 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
3565 	if (!readdir->rd_dircount)
3566 		readdir->rd_dircount = INT_MAX;
3567 
3568 	readdir->xdr = xdr;
3569 	readdir->rd_maxcount = maxcount;
3570 	readdir->common.err = 0;
3571 	readdir->cookie_offset = 0;
3572 
3573 	offset = readdir->rd_cookie;
3574 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3575 			      &offset,
3576 			      &readdir->common, nfsd4_encode_dirent);
3577 	if (nfserr == nfs_ok &&
3578 	    readdir->common.err == nfserr_toosmall &&
3579 	    xdr->buf->len == starting_len + 8) {
3580 		/* nothing encoded; which limit did we hit?: */
3581 		if (maxcount - 16 < bytes_left)
3582 			/* It was the fault of rd_maxcount: */
3583 			nfserr = nfserr_toosmall;
3584 		else
3585 			/* We ran out of buffer space: */
3586 			nfserr = nfserr_resource;
3587 	}
3588 	if (nfserr)
3589 		goto err_no_verf;
3590 
3591 	if (readdir->cookie_offset) {
3592 		wire_offset = cpu_to_be64(offset);
3593 		write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset,
3594 							&wire_offset, 8);
3595 	}
3596 
3597 	p = xdr_reserve_space(xdr, 8);
3598 	if (!p) {
3599 		WARN_ON_ONCE(1);
3600 		goto err_no_verf;
3601 	}
3602 	*p++ = 0;	/* no more entries */
3603 	*p++ = htonl(readdir->common.err == nfserr_eof);
3604 
3605 	return 0;
3606 err_no_verf:
3607 	xdr_truncate_encode(xdr, starting_len);
3608 	return nfserr;
3609 }
3610 
3611 static __be32
3612 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3613 {
3614 	struct xdr_stream *xdr = &resp->xdr;
3615 	__be32 *p;
3616 
3617 	if (!nfserr) {
3618 		p = xdr_reserve_space(xdr, 20);
3619 		if (!p)
3620 			return nfserr_resource;
3621 		p = encode_cinfo(p, &remove->rm_cinfo);
3622 	}
3623 	return nfserr;
3624 }
3625 
3626 static __be32
3627 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3628 {
3629 	struct xdr_stream *xdr = &resp->xdr;
3630 	__be32 *p;
3631 
3632 	if (!nfserr) {
3633 		p = xdr_reserve_space(xdr, 40);
3634 		if (!p)
3635 			return nfserr_resource;
3636 		p = encode_cinfo(p, &rename->rn_sinfo);
3637 		p = encode_cinfo(p, &rename->rn_tinfo);
3638 	}
3639 	return nfserr;
3640 }
3641 
3642 static __be32
3643 nfsd4_do_encode_secinfo(struct xdr_stream *xdr,
3644 			 __be32 nfserr, struct svc_export *exp)
3645 {
3646 	u32 i, nflavs, supported;
3647 	struct exp_flavor_info *flavs;
3648 	struct exp_flavor_info def_flavs[2];
3649 	__be32 *p, *flavorsp;
3650 	static bool report = true;
3651 
3652 	if (nfserr)
3653 		goto out;
3654 	nfserr = nfserr_resource;
3655 	if (exp->ex_nflavors) {
3656 		flavs = exp->ex_flavors;
3657 		nflavs = exp->ex_nflavors;
3658 	} else { /* Handling of some defaults in absence of real secinfo: */
3659 		flavs = def_flavs;
3660 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3661 			nflavs = 2;
3662 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3663 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3664 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3665 			nflavs = 1;
3666 			flavs[0].pseudoflavor
3667 					= svcauth_gss_flavor(exp->ex_client);
3668 		} else {
3669 			nflavs = 1;
3670 			flavs[0].pseudoflavor
3671 					= exp->ex_client->flavour->flavour;
3672 		}
3673 	}
3674 
3675 	supported = 0;
3676 	p = xdr_reserve_space(xdr, 4);
3677 	if (!p)
3678 		goto out;
3679 	flavorsp = p++;		/* to be backfilled later */
3680 
3681 	for (i = 0; i < nflavs; i++) {
3682 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
3683 		struct rpcsec_gss_info info;
3684 
3685 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
3686 			supported++;
3687 			p = xdr_reserve_space(xdr, 4 + 4 +
3688 					      XDR_LEN(info.oid.len) + 4 + 4);
3689 			if (!p)
3690 				goto out;
3691 			*p++ = cpu_to_be32(RPC_AUTH_GSS);
3692 			p = xdr_encode_opaque(p,  info.oid.data, info.oid.len);
3693 			*p++ = cpu_to_be32(info.qop);
3694 			*p++ = cpu_to_be32(info.service);
3695 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
3696 			supported++;
3697 			p = xdr_reserve_space(xdr, 4);
3698 			if (!p)
3699 				goto out;
3700 			*p++ = cpu_to_be32(pf);
3701 		} else {
3702 			if (report)
3703 				pr_warn("NFS: SECINFO: security flavor %u "
3704 					"is not supported\n", pf);
3705 		}
3706 	}
3707 
3708 	if (nflavs != supported)
3709 		report = false;
3710 	*flavorsp = htonl(supported);
3711 	nfserr = 0;
3712 out:
3713 	if (exp)
3714 		exp_put(exp);
3715 	return nfserr;
3716 }
3717 
3718 static __be32
3719 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3720 		     struct nfsd4_secinfo *secinfo)
3721 {
3722 	struct xdr_stream *xdr = &resp->xdr;
3723 
3724 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->si_exp);
3725 }
3726 
3727 static __be32
3728 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3729 		     struct nfsd4_secinfo_no_name *secinfo)
3730 {
3731 	struct xdr_stream *xdr = &resp->xdr;
3732 
3733 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->sin_exp);
3734 }
3735 
3736 /*
3737  * The SETATTR encode routine is special -- it always encodes a bitmap,
3738  * regardless of the error status.
3739  */
3740 static __be32
3741 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3742 {
3743 	struct xdr_stream *xdr = &resp->xdr;
3744 	__be32 *p;
3745 
3746 	p = xdr_reserve_space(xdr, 16);
3747 	if (!p)
3748 		return nfserr_resource;
3749 	if (nfserr) {
3750 		*p++ = cpu_to_be32(3);
3751 		*p++ = cpu_to_be32(0);
3752 		*p++ = cpu_to_be32(0);
3753 		*p++ = cpu_to_be32(0);
3754 	}
3755 	else {
3756 		*p++ = cpu_to_be32(3);
3757 		*p++ = cpu_to_be32(setattr->sa_bmval[0]);
3758 		*p++ = cpu_to_be32(setattr->sa_bmval[1]);
3759 		*p++ = cpu_to_be32(setattr->sa_bmval[2]);
3760 	}
3761 	return nfserr;
3762 }
3763 
3764 static __be32
3765 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3766 {
3767 	struct xdr_stream *xdr = &resp->xdr;
3768 	__be32 *p;
3769 
3770 	if (!nfserr) {
3771 		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
3772 		if (!p)
3773 			return nfserr_resource;
3774 		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
3775 		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
3776 						NFS4_VERIFIER_SIZE);
3777 	}
3778 	else if (nfserr == nfserr_clid_inuse) {
3779 		p = xdr_reserve_space(xdr, 8);
3780 		if (!p)
3781 			return nfserr_resource;
3782 		*p++ = cpu_to_be32(0);
3783 		*p++ = cpu_to_be32(0);
3784 	}
3785 	return nfserr;
3786 }
3787 
3788 static __be32
3789 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3790 {
3791 	struct xdr_stream *xdr = &resp->xdr;
3792 	__be32 *p;
3793 
3794 	if (!nfserr) {
3795 		p = xdr_reserve_space(xdr, 16);
3796 		if (!p)
3797 			return nfserr_resource;
3798 		*p++ = cpu_to_be32(write->wr_bytes_written);
3799 		*p++ = cpu_to_be32(write->wr_how_written);
3800 		p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
3801 							NFS4_VERIFIER_SIZE);
3802 	}
3803 	return nfserr;
3804 }
3805 
3806 static const u32 nfs4_minimal_spo_must_enforce[2] = {
3807 	[1] = 1 << (OP_BIND_CONN_TO_SESSION - 32) |
3808 	      1 << (OP_EXCHANGE_ID - 32) |
3809 	      1 << (OP_CREATE_SESSION - 32) |
3810 	      1 << (OP_DESTROY_SESSION - 32) |
3811 	      1 << (OP_DESTROY_CLIENTID - 32)
3812 };
3813 
3814 static __be32
3815 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
3816 			 struct nfsd4_exchange_id *exid)
3817 {
3818 	struct xdr_stream *xdr = &resp->xdr;
3819 	__be32 *p;
3820 	char *major_id;
3821 	char *server_scope;
3822 	int major_id_sz;
3823 	int server_scope_sz;
3824 	uint64_t minor_id = 0;
3825 
3826 	if (nfserr)
3827 		return nfserr;
3828 
3829 	major_id = utsname()->nodename;
3830 	major_id_sz = strlen(major_id);
3831 	server_scope = utsname()->nodename;
3832 	server_scope_sz = strlen(server_scope);
3833 
3834 	p = xdr_reserve_space(xdr,
3835 		8 /* eir_clientid */ +
3836 		4 /* eir_sequenceid */ +
3837 		4 /* eir_flags */ +
3838 		4 /* spr_how */);
3839 	if (!p)
3840 		return nfserr_resource;
3841 
3842 	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
3843 	*p++ = cpu_to_be32(exid->seqid);
3844 	*p++ = cpu_to_be32(exid->flags);
3845 
3846 	*p++ = cpu_to_be32(exid->spa_how);
3847 
3848 	switch (exid->spa_how) {
3849 	case SP4_NONE:
3850 		break;
3851 	case SP4_MACH_CRED:
3852 		/* spo_must_enforce, spo_must_allow */
3853 		p = xdr_reserve_space(xdr, 16);
3854 		if (!p)
3855 			return nfserr_resource;
3856 
3857 		/* spo_must_enforce bitmap: */
3858 		*p++ = cpu_to_be32(2);
3859 		*p++ = cpu_to_be32(nfs4_minimal_spo_must_enforce[0]);
3860 		*p++ = cpu_to_be32(nfs4_minimal_spo_must_enforce[1]);
3861 		/* empty spo_must_allow bitmap: */
3862 		*p++ = cpu_to_be32(0);
3863 
3864 		break;
3865 	default:
3866 		WARN_ON_ONCE(1);
3867 	}
3868 
3869 	p = xdr_reserve_space(xdr,
3870 		8 /* so_minor_id */ +
3871 		4 /* so_major_id.len */ +
3872 		(XDR_QUADLEN(major_id_sz) * 4) +
3873 		4 /* eir_server_scope.len */ +
3874 		(XDR_QUADLEN(server_scope_sz) * 4) +
3875 		4 /* eir_server_impl_id.count (0) */);
3876 	if (!p)
3877 		return nfserr_resource;
3878 
3879 	/* The server_owner struct */
3880 	p = xdr_encode_hyper(p, minor_id);      /* Minor id */
3881 	/* major id */
3882 	p = xdr_encode_opaque(p, major_id, major_id_sz);
3883 
3884 	/* Server scope */
3885 	p = xdr_encode_opaque(p, server_scope, server_scope_sz);
3886 
3887 	/* Implementation id */
3888 	*p++ = cpu_to_be32(0);	/* zero length nfs_impl_id4 array */
3889 	return 0;
3890 }
3891 
3892 static __be32
3893 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
3894 			    struct nfsd4_create_session *sess)
3895 {
3896 	struct xdr_stream *xdr = &resp->xdr;
3897 	__be32 *p;
3898 
3899 	if (nfserr)
3900 		return nfserr;
3901 
3902 	p = xdr_reserve_space(xdr, 24);
3903 	if (!p)
3904 		return nfserr_resource;
3905 	p = xdr_encode_opaque_fixed(p, sess->sessionid.data,
3906 					NFS4_MAX_SESSIONID_LEN);
3907 	*p++ = cpu_to_be32(sess->seqid);
3908 	*p++ = cpu_to_be32(sess->flags);
3909 
3910 	p = xdr_reserve_space(xdr, 28);
3911 	if (!p)
3912 		return nfserr_resource;
3913 	*p++ = cpu_to_be32(0); /* headerpadsz */
3914 	*p++ = cpu_to_be32(sess->fore_channel.maxreq_sz);
3915 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_sz);
3916 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_cached);
3917 	*p++ = cpu_to_be32(sess->fore_channel.maxops);
3918 	*p++ = cpu_to_be32(sess->fore_channel.maxreqs);
3919 	*p++ = cpu_to_be32(sess->fore_channel.nr_rdma_attrs);
3920 
3921 	if (sess->fore_channel.nr_rdma_attrs) {
3922 		p = xdr_reserve_space(xdr, 4);
3923 		if (!p)
3924 			return nfserr_resource;
3925 		*p++ = cpu_to_be32(sess->fore_channel.rdma_attrs);
3926 	}
3927 
3928 	p = xdr_reserve_space(xdr, 28);
3929 	if (!p)
3930 		return nfserr_resource;
3931 	*p++ = cpu_to_be32(0); /* headerpadsz */
3932 	*p++ = cpu_to_be32(sess->back_channel.maxreq_sz);
3933 	*p++ = cpu_to_be32(sess->back_channel.maxresp_sz);
3934 	*p++ = cpu_to_be32(sess->back_channel.maxresp_cached);
3935 	*p++ = cpu_to_be32(sess->back_channel.maxops);
3936 	*p++ = cpu_to_be32(sess->back_channel.maxreqs);
3937 	*p++ = cpu_to_be32(sess->back_channel.nr_rdma_attrs);
3938 
3939 	if (sess->back_channel.nr_rdma_attrs) {
3940 		p = xdr_reserve_space(xdr, 4);
3941 		if (!p)
3942 			return nfserr_resource;
3943 		*p++ = cpu_to_be32(sess->back_channel.rdma_attrs);
3944 	}
3945 	return 0;
3946 }
3947 
3948 static __be32
3949 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
3950 		      struct nfsd4_sequence *seq)
3951 {
3952 	struct xdr_stream *xdr = &resp->xdr;
3953 	__be32 *p;
3954 
3955 	if (nfserr)
3956 		return nfserr;
3957 
3958 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 20);
3959 	if (!p)
3960 		return nfserr_resource;
3961 	p = xdr_encode_opaque_fixed(p, seq->sessionid.data,
3962 					NFS4_MAX_SESSIONID_LEN);
3963 	*p++ = cpu_to_be32(seq->seqid);
3964 	*p++ = cpu_to_be32(seq->slotid);
3965 	/* Note slotid's are numbered from zero: */
3966 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_highest_slotid */
3967 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_target_highest_slotid */
3968 	*p++ = cpu_to_be32(seq->status_flags);
3969 
3970 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
3971 	return 0;
3972 }
3973 
3974 static __be32
3975 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
3976 			  struct nfsd4_test_stateid *test_stateid)
3977 {
3978 	struct xdr_stream *xdr = &resp->xdr;
3979 	struct nfsd4_test_stateid_id *stateid, *next;
3980 	__be32 *p;
3981 
3982 	if (nfserr)
3983 		return nfserr;
3984 
3985 	p = xdr_reserve_space(xdr, 4 + (4 * test_stateid->ts_num_ids));
3986 	if (!p)
3987 		return nfserr_resource;
3988 	*p++ = htonl(test_stateid->ts_num_ids);
3989 
3990 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
3991 		*p++ = stateid->ts_id_status;
3992 	}
3993 
3994 	return nfserr;
3995 }
3996 
3997 #ifdef CONFIG_NFSD_PNFS
3998 static __be32
3999 nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
4000 		struct nfsd4_getdeviceinfo *gdev)
4001 {
4002 	struct xdr_stream *xdr = &resp->xdr;
4003 	const struct nfsd4_layout_ops *ops =
4004 		nfsd4_layout_ops[gdev->gd_layout_type];
4005 	u32 starting_len = xdr->buf->len, needed_len;
4006 	__be32 *p;
4007 
4008 	dprintk("%s: err %d\n", __func__, nfserr);
4009 	if (nfserr)
4010 		goto out;
4011 
4012 	nfserr = nfserr_resource;
4013 	p = xdr_reserve_space(xdr, 4);
4014 	if (!p)
4015 		goto out;
4016 
4017 	*p++ = cpu_to_be32(gdev->gd_layout_type);
4018 
4019 	/* If maxcount is 0 then just update notifications */
4020 	if (gdev->gd_maxcount != 0) {
4021 		nfserr = ops->encode_getdeviceinfo(xdr, gdev);
4022 		if (nfserr) {
4023 			/*
4024 			 * We don't bother to burden the layout drivers with
4025 			 * enforcing gd_maxcount, just tell the client to
4026 			 * come back with a bigger buffer if it's not enough.
4027 			 */
4028 			if (xdr->buf->len + 4 > gdev->gd_maxcount)
4029 				goto toosmall;
4030 			goto out;
4031 		}
4032 	}
4033 
4034 	nfserr = nfserr_resource;
4035 	if (gdev->gd_notify_types) {
4036 		p = xdr_reserve_space(xdr, 4 + 4);
4037 		if (!p)
4038 			goto out;
4039 		*p++ = cpu_to_be32(1);			/* bitmap length */
4040 		*p++ = cpu_to_be32(gdev->gd_notify_types);
4041 	} else {
4042 		p = xdr_reserve_space(xdr, 4);
4043 		if (!p)
4044 			goto out;
4045 		*p++ = 0;
4046 	}
4047 
4048 	nfserr = 0;
4049 out:
4050 	kfree(gdev->gd_device);
4051 	dprintk("%s: done: %d\n", __func__, be32_to_cpu(nfserr));
4052 	return nfserr;
4053 
4054 toosmall:
4055 	dprintk("%s: maxcount too small\n", __func__);
4056 	needed_len = xdr->buf->len + 4 /* notifications */;
4057 	xdr_truncate_encode(xdr, starting_len);
4058 	p = xdr_reserve_space(xdr, 4);
4059 	if (!p) {
4060 		nfserr = nfserr_resource;
4061 	} else {
4062 		*p++ = cpu_to_be32(needed_len);
4063 		nfserr = nfserr_toosmall;
4064 	}
4065 	goto out;
4066 }
4067 
4068 static __be32
4069 nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr,
4070 		struct nfsd4_layoutget *lgp)
4071 {
4072 	struct xdr_stream *xdr = &resp->xdr;
4073 	const struct nfsd4_layout_ops *ops =
4074 		nfsd4_layout_ops[lgp->lg_layout_type];
4075 	__be32 *p;
4076 
4077 	dprintk("%s: err %d\n", __func__, nfserr);
4078 	if (nfserr)
4079 		goto out;
4080 
4081 	nfserr = nfserr_resource;
4082 	p = xdr_reserve_space(xdr, 36 + sizeof(stateid_opaque_t));
4083 	if (!p)
4084 		goto out;
4085 
4086 	*p++ = cpu_to_be32(1);	/* we always set return-on-close */
4087 	*p++ = cpu_to_be32(lgp->lg_sid.si_generation);
4088 	p = xdr_encode_opaque_fixed(p, &lgp->lg_sid.si_opaque,
4089 				    sizeof(stateid_opaque_t));
4090 
4091 	*p++ = cpu_to_be32(1);	/* we always return a single layout */
4092 	p = xdr_encode_hyper(p, lgp->lg_seg.offset);
4093 	p = xdr_encode_hyper(p, lgp->lg_seg.length);
4094 	*p++ = cpu_to_be32(lgp->lg_seg.iomode);
4095 	*p++ = cpu_to_be32(lgp->lg_layout_type);
4096 
4097 	nfserr = ops->encode_layoutget(xdr, lgp);
4098 out:
4099 	kfree(lgp->lg_content);
4100 	return nfserr;
4101 }
4102 
4103 static __be32
4104 nfsd4_encode_layoutcommit(struct nfsd4_compoundres *resp, __be32 nfserr,
4105 			  struct nfsd4_layoutcommit *lcp)
4106 {
4107 	struct xdr_stream *xdr = &resp->xdr;
4108 	__be32 *p;
4109 
4110 	if (nfserr)
4111 		return nfserr;
4112 
4113 	p = xdr_reserve_space(xdr, 4);
4114 	if (!p)
4115 		return nfserr_resource;
4116 	*p++ = cpu_to_be32(lcp->lc_size_chg);
4117 	if (lcp->lc_size_chg) {
4118 		p = xdr_reserve_space(xdr, 8);
4119 		if (!p)
4120 			return nfserr_resource;
4121 		p = xdr_encode_hyper(p, lcp->lc_newsize);
4122 	}
4123 
4124 	return nfs_ok;
4125 }
4126 
4127 static __be32
4128 nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
4129 		struct nfsd4_layoutreturn *lrp)
4130 {
4131 	struct xdr_stream *xdr = &resp->xdr;
4132 	__be32 *p;
4133 
4134 	if (nfserr)
4135 		return nfserr;
4136 
4137 	p = xdr_reserve_space(xdr, 4);
4138 	if (!p)
4139 		return nfserr_resource;
4140 	*p++ = cpu_to_be32(lrp->lrs_present);
4141 	if (lrp->lrs_present)
4142 		return nfsd4_encode_stateid(xdr, &lrp->lr_sid);
4143 	return nfs_ok;
4144 }
4145 #endif /* CONFIG_NFSD_PNFS */
4146 
4147 static __be32
4148 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
4149 		  struct nfsd4_seek *seek)
4150 {
4151 	__be32 *p;
4152 
4153 	if (nfserr)
4154 		return nfserr;
4155 
4156 	p = xdr_reserve_space(&resp->xdr, 4 + 8);
4157 	*p++ = cpu_to_be32(seek->seek_eof);
4158 	p = xdr_encode_hyper(p, seek->seek_pos);
4159 
4160 	return nfserr;
4161 }
4162 
4163 static __be32
4164 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
4165 {
4166 	return nfserr;
4167 }
4168 
4169 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
4170 
4171 /*
4172  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
4173  * since we don't need to filter out obsolete ops as this is
4174  * done in the decoding phase.
4175  */
4176 static nfsd4_enc nfsd4_enc_ops[] = {
4177 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
4178 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
4179 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
4180 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
4181 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
4182 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4183 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
4184 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
4185 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
4186 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
4187 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
4188 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
4189 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
4190 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
4191 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4192 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
4193 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
4194 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
4195 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
4196 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4197 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
4198 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4199 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
4200 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
4201 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
4202 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
4203 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
4204 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
4205 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
4206 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
4207 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
4208 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
4209 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
4210 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
4211 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4212 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
4213 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
4214 
4215 	/* NFSv4.1 operations */
4216 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
4217 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
4218 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
4219 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
4220 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
4221 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
4222 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4223 #ifdef CONFIG_NFSD_PNFS
4224 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_getdeviceinfo,
4225 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4226 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_layoutcommit,
4227 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_layoutget,
4228 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_layoutreturn,
4229 #else
4230 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
4231 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4232 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
4233 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
4234 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4235 #endif
4236 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
4237 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
4238 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
4239 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
4240 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4241 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
4242 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
4243 
4244 	/* NFSv4.2 operations */
4245 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4246 	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_noop,
4247 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
4248 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4249 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
4250 	[OP_LAYOUTERROR]	= (nfsd4_enc)nfsd4_encode_noop,
4251 	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,
4252 	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,
4253 	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_noop,
4254 	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_noop,
4255 	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,
4256 	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,
4257 };
4258 
4259 /*
4260  * Calculate whether we still have space to encode repsize bytes.
4261  * There are two considerations:
4262  *     - For NFS versions >=4.1, the size of the reply must stay within
4263  *       session limits
4264  *     - For all NFS versions, we must stay within limited preallocated
4265  *       buffer space.
4266  *
4267  * This is called before the operation is processed, so can only provide
4268  * an upper estimate.  For some nonidempotent operations (such as
4269  * getattr), it's not necessarily a problem if that estimate is wrong,
4270  * as we can fail it after processing without significant side effects.
4271  */
4272 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
4273 {
4274 	struct xdr_buf *buf = &resp->rqstp->rq_res;
4275 	struct nfsd4_slot *slot = resp->cstate.slot;
4276 
4277 	if (buf->len + respsize <= buf->buflen)
4278 		return nfs_ok;
4279 	if (!nfsd4_has_session(&resp->cstate))
4280 		return nfserr_resource;
4281 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
4282 		WARN_ON_ONCE(1);
4283 		return nfserr_rep_too_big_to_cache;
4284 	}
4285 	return nfserr_rep_too_big;
4286 }
4287 
4288 void
4289 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
4290 {
4291 	struct xdr_stream *xdr = &resp->xdr;
4292 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
4293 	struct svc_rqst *rqstp = resp->rqstp;
4294 	int post_err_offset;
4295 	nfsd4_enc encoder;
4296 	__be32 *p;
4297 
4298 	p = xdr_reserve_space(xdr, 8);
4299 	if (!p) {
4300 		WARN_ON_ONCE(1);
4301 		return;
4302 	}
4303 	*p++ = cpu_to_be32(op->opnum);
4304 	post_err_offset = xdr->buf->len;
4305 
4306 	if (op->opnum == OP_ILLEGAL)
4307 		goto status;
4308 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
4309 	       !nfsd4_enc_ops[op->opnum]);
4310 	encoder = nfsd4_enc_ops[op->opnum];
4311 	op->status = encoder(resp, op->status, &op->u);
4312 	xdr_commit_encode(xdr);
4313 
4314 	/* nfsd4_check_resp_size guarantees enough room for error status */
4315 	if (!op->status) {
4316 		int space_needed = 0;
4317 		if (!nfsd4_last_compound_op(rqstp))
4318 			space_needed = COMPOUND_ERR_SLACK_SPACE;
4319 		op->status = nfsd4_check_resp_size(resp, space_needed);
4320 	}
4321 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
4322 		struct nfsd4_slot *slot = resp->cstate.slot;
4323 
4324 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
4325 			op->status = nfserr_rep_too_big_to_cache;
4326 		else
4327 			op->status = nfserr_rep_too_big;
4328 	}
4329 	if (op->status == nfserr_resource ||
4330 	    op->status == nfserr_rep_too_big ||
4331 	    op->status == nfserr_rep_too_big_to_cache) {
4332 		/*
4333 		 * The operation may have already been encoded or
4334 		 * partially encoded.  No op returns anything additional
4335 		 * in the case of one of these three errors, so we can
4336 		 * just truncate back to after the status.  But it's a
4337 		 * bug if we had to do this on a non-idempotent op:
4338 		 */
4339 		warn_on_nonidempotent_op(op);
4340 		xdr_truncate_encode(xdr, post_err_offset);
4341 	}
4342 	if (so) {
4343 		int len = xdr->buf->len - post_err_offset;
4344 
4345 		so->so_replay.rp_status = op->status;
4346 		so->so_replay.rp_buflen = len;
4347 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
4348 						so->so_replay.rp_buf, len);
4349 	}
4350 status:
4351 	/* Note that op->status is already in network byte order: */
4352 	write_bytes_to_xdr_buf(xdr->buf, post_err_offset - 4, &op->status, 4);
4353 }
4354 
4355 /*
4356  * Encode the reply stored in the stateowner reply cache
4357  *
4358  * XDR note: do not encode rp->rp_buflen: the buffer contains the
4359  * previously sent already encoded operation.
4360  */
4361 void
4362 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
4363 {
4364 	__be32 *p;
4365 	struct nfs4_replay *rp = op->replay;
4366 
4367 	BUG_ON(!rp);
4368 
4369 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
4370 	if (!p) {
4371 		WARN_ON_ONCE(1);
4372 		return;
4373 	}
4374 	*p++ = cpu_to_be32(op->opnum);
4375 	*p++ = rp->rp_status;  /* already xdr'ed */
4376 
4377 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
4378 }
4379 
4380 int
4381 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
4382 {
4383         return xdr_ressize_check(rqstp, p);
4384 }
4385 
4386 int nfsd4_release_compoundargs(void *rq, __be32 *p, void *resp)
4387 {
4388 	struct svc_rqst *rqstp = rq;
4389 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4390 
4391 	if (args->ops != args->iops) {
4392 		kfree(args->ops);
4393 		args->ops = args->iops;
4394 	}
4395 	kfree(args->tmpp);
4396 	args->tmpp = NULL;
4397 	while (args->to_free) {
4398 		struct svcxdr_tmpbuf *tb = args->to_free;
4399 		args->to_free = tb->next;
4400 		kfree(tb);
4401 	}
4402 	return 1;
4403 }
4404 
4405 int
4406 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundargs *args)
4407 {
4408 	if (rqstp->rq_arg.head[0].iov_len % 4) {
4409 		/* client is nuts */
4410 		dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)",
4411 			__func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid));
4412 		return 0;
4413 	}
4414 	args->p = p;
4415 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
4416 	args->pagelist = rqstp->rq_arg.pages;
4417 	args->pagelen = rqstp->rq_arg.page_len;
4418 	args->tmpp = NULL;
4419 	args->to_free = NULL;
4420 	args->ops = args->iops;
4421 	args->rqstp = rqstp;
4422 
4423 	return !nfsd4_decode_compound(args);
4424 }
4425 
4426 int
4427 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundres *resp)
4428 {
4429 	/*
4430 	 * All that remains is to write the tag and operation count...
4431 	 */
4432 	struct xdr_buf *buf = resp->xdr.buf;
4433 
4434 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
4435 				 buf->tail[0].iov_len);
4436 
4437 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
4438 
4439 	p = resp->tagp;
4440 	*p++ = htonl(resp->taglen);
4441 	memcpy(p, resp->tag, resp->taglen);
4442 	p += XDR_QUADLEN(resp->taglen);
4443 	*p++ = htonl(resp->opcnt);
4444 
4445 	nfsd4_sequence_done(resp);
4446 	return 1;
4447 }
4448 
4449 /*
4450  * Local variables:
4451  *  c-basic-offset: 8
4452  * End:
4453  */
4454