xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision 32981ea5)
1 /*
2  *  Server-side XDR for NFSv4
3  *
4  *  Copyright (c) 2002 The Regents of the University of Michigan.
5  *  All rights reserved.
6  *
7  *  Kendrick Smith <kmsmith@umich.edu>
8  *  Andy Adamson   <andros@umich.edu>
9  *
10  *  Redistribution and use in source and binary forms, with or without
11  *  modification, are permitted provided that the following conditions
12  *  are met:
13  *
14  *  1. Redistributions of source code must retain the above copyright
15  *     notice, this list of conditions and the following disclaimer.
16  *  2. Redistributions in binary form must reproduce the above copyright
17  *     notice, this list of conditions and the following disclaimer in the
18  *     documentation and/or other materials provided with the distribution.
19  *  3. Neither the name of the University nor the names of its
20  *     contributors may be used to endorse or promote products derived
21  *     from this software without specific prior written permission.
22  *
23  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
24  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
30  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 #include <linux/file.h>
37 #include <linux/slab.h>
38 #include <linux/namei.h>
39 #include <linux/statfs.h>
40 #include <linux/utsname.h>
41 #include <linux/pagemap.h>
42 #include <linux/sunrpc/svcauth_gss.h>
43 
44 #include "idmap.h"
45 #include "acl.h"
46 #include "xdr4.h"
47 #include "vfs.h"
48 #include "state.h"
49 #include "cache.h"
50 #include "netns.h"
51 #include "pnfs.h"
52 
53 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
54 #include <linux/security.h>
55 #endif
56 
57 
58 #define NFSDDBG_FACILITY		NFSDDBG_XDR
59 
60 /*
61  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
62  * directory in order to indicate to the client that a filesystem boundary is present
63  * We use a fixed fsid for a referral
64  */
65 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
66 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
67 
68 static __be32
69 check_filename(char *str, int len)
70 {
71 	int i;
72 
73 	if (len == 0)
74 		return nfserr_inval;
75 	if (isdotent(str, len))
76 		return nfserr_badname;
77 	for (i = 0; i < len; i++)
78 		if (str[i] == '/')
79 			return nfserr_badname;
80 	return 0;
81 }
82 
83 #define DECODE_HEAD				\
84 	__be32 *p;				\
85 	__be32 status
86 #define DECODE_TAIL				\
87 	status = 0;				\
88 out:						\
89 	return status;				\
90 xdr_error:					\
91 	dprintk("NFSD: xdr error (%s:%d)\n",	\
92 			__FILE__, __LINE__);	\
93 	status = nfserr_bad_xdr;		\
94 	goto out
95 
96 #define READMEM(x,nbytes) do {			\
97 	x = (char *)p;				\
98 	p += XDR_QUADLEN(nbytes);		\
99 } while (0)
100 #define SAVEMEM(x,nbytes) do {			\
101 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
102  		savemem(argp, p, nbytes) :	\
103  		(char *)p)) {			\
104 		dprintk("NFSD: xdr error (%s:%d)\n", \
105 				__FILE__, __LINE__); \
106 		goto xdr_error;			\
107 		}				\
108 	p += XDR_QUADLEN(nbytes);		\
109 } while (0)
110 #define COPYMEM(x,nbytes) do {			\
111 	memcpy((x), p, nbytes);			\
112 	p += XDR_QUADLEN(nbytes);		\
113 } while (0)
114 
115 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
116 #define READ_BUF(nbytes)  do {			\
117 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
118 		p = argp->p;			\
119 		argp->p += XDR_QUADLEN(nbytes);	\
120 	} else if (!(p = read_buf(argp, nbytes))) { \
121 		dprintk("NFSD: xdr error (%s:%d)\n", \
122 				__FILE__, __LINE__); \
123 		goto xdr_error;			\
124 	}					\
125 } while (0)
126 
127 static void next_decode_page(struct nfsd4_compoundargs *argp)
128 {
129 	argp->p = page_address(argp->pagelist[0]);
130 	argp->pagelist++;
131 	if (argp->pagelen < PAGE_SIZE) {
132 		argp->end = argp->p + (argp->pagelen>>2);
133 		argp->pagelen = 0;
134 	} else {
135 		argp->end = argp->p + (PAGE_SIZE>>2);
136 		argp->pagelen -= PAGE_SIZE;
137 	}
138 }
139 
140 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
141 {
142 	/* We want more bytes than seem to be available.
143 	 * Maybe we need a new page, maybe we have just run out
144 	 */
145 	unsigned int avail = (char *)argp->end - (char *)argp->p;
146 	__be32 *p;
147 	if (avail + argp->pagelen < nbytes)
148 		return NULL;
149 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
150 		return NULL;
151 	/* ok, we can do it with the current plus the next page */
152 	if (nbytes <= sizeof(argp->tmp))
153 		p = argp->tmp;
154 	else {
155 		kfree(argp->tmpp);
156 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
157 		if (!p)
158 			return NULL;
159 
160 	}
161 	/*
162 	 * The following memcpy is safe because read_buf is always
163 	 * called with nbytes > avail, and the two cases above both
164 	 * guarantee p points to at least nbytes bytes.
165 	 */
166 	memcpy(p, argp->p, avail);
167 	next_decode_page(argp);
168 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
169 	argp->p += XDR_QUADLEN(nbytes - avail);
170 	return p;
171 }
172 
173 static int zero_clientid(clientid_t *clid)
174 {
175 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
176 }
177 
178 /**
179  * svcxdr_tmpalloc - allocate memory to be freed after compound processing
180  * @argp: NFSv4 compound argument structure
181  * @p: pointer to be freed (with kfree())
182  *
183  * Marks @p to be freed when processing the compound operation
184  * described in @argp finishes.
185  */
186 static void *
187 svcxdr_tmpalloc(struct nfsd4_compoundargs *argp, u32 len)
188 {
189 	struct svcxdr_tmpbuf *tb;
190 
191 	tb = kmalloc(sizeof(*tb) + len, GFP_KERNEL);
192 	if (!tb)
193 		return NULL;
194 	tb->next = argp->to_free;
195 	argp->to_free = tb;
196 	return tb->buf;
197 }
198 
199 /*
200  * For xdr strings that need to be passed to other kernel api's
201  * as null-terminated strings.
202  *
203  * Note null-terminating in place usually isn't safe since the
204  * buffer might end on a page boundary.
205  */
206 static char *
207 svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len)
208 {
209 	char *p = svcxdr_tmpalloc(argp, len + 1);
210 
211 	if (!p)
212 		return NULL;
213 	memcpy(p, buf, len);
214 	p[len] = '\0';
215 	return p;
216 }
217 
218 /**
219  * savemem - duplicate a chunk of memory for later processing
220  * @argp: NFSv4 compound argument structure to be freed with
221  * @p: pointer to be duplicated
222  * @nbytes: length to be duplicated
223  *
224  * Returns a pointer to a copy of @nbytes bytes of memory at @p
225  * that are preserved until processing of the NFSv4 compound
226  * operation described by @argp finishes.
227  */
228 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
229 {
230 	void *ret;
231 
232 	ret = svcxdr_tmpalloc(argp, nbytes);
233 	if (!ret)
234 		return NULL;
235 	memcpy(ret, p, nbytes);
236 	return ret;
237 }
238 
239 /*
240  * We require the high 32 bits of 'seconds' to be 0, and
241  * we ignore all 32 bits of 'nseconds'.
242  */
243 static __be32
244 nfsd4_decode_time(struct nfsd4_compoundargs *argp, struct timespec *tv)
245 {
246 	DECODE_HEAD;
247 	u64 sec;
248 
249 	READ_BUF(12);
250 	p = xdr_decode_hyper(p, &sec);
251 	tv->tv_sec = sec;
252 	tv->tv_nsec = be32_to_cpup(p++);
253 	if (tv->tv_nsec >= (u32)1000000000)
254 		return nfserr_inval;
255 
256 	DECODE_TAIL;
257 }
258 
259 static __be32
260 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
261 {
262 	u32 bmlen;
263 	DECODE_HEAD;
264 
265 	bmval[0] = 0;
266 	bmval[1] = 0;
267 	bmval[2] = 0;
268 
269 	READ_BUF(4);
270 	bmlen = be32_to_cpup(p++);
271 	if (bmlen > 1000)
272 		goto xdr_error;
273 
274 	READ_BUF(bmlen << 2);
275 	if (bmlen > 0)
276 		bmval[0] = be32_to_cpup(p++);
277 	if (bmlen > 1)
278 		bmval[1] = be32_to_cpup(p++);
279 	if (bmlen > 2)
280 		bmval[2] = be32_to_cpup(p++);
281 
282 	DECODE_TAIL;
283 }
284 
285 static __be32
286 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
287 		   struct iattr *iattr, struct nfs4_acl **acl,
288 		   struct xdr_netobj *label)
289 {
290 	int expected_len, len = 0;
291 	u32 dummy32;
292 	char *buf;
293 
294 	DECODE_HEAD;
295 	iattr->ia_valid = 0;
296 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
297 		return status;
298 
299 	READ_BUF(4);
300 	expected_len = be32_to_cpup(p++);
301 
302 	if (bmval[0] & FATTR4_WORD0_SIZE) {
303 		READ_BUF(8);
304 		len += 8;
305 		p = xdr_decode_hyper(p, &iattr->ia_size);
306 		iattr->ia_valid |= ATTR_SIZE;
307 	}
308 	if (bmval[0] & FATTR4_WORD0_ACL) {
309 		u32 nace;
310 		struct nfs4_ace *ace;
311 
312 		READ_BUF(4); len += 4;
313 		nace = be32_to_cpup(p++);
314 
315 		if (nace > NFS4_ACL_MAX)
316 			return nfserr_fbig;
317 
318 		*acl = svcxdr_tmpalloc(argp, nfs4_acl_bytes(nace));
319 		if (*acl == NULL)
320 			return nfserr_jukebox;
321 
322 		(*acl)->naces = nace;
323 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
324 			READ_BUF(16); len += 16;
325 			ace->type = be32_to_cpup(p++);
326 			ace->flag = be32_to_cpup(p++);
327 			ace->access_mask = be32_to_cpup(p++);
328 			dummy32 = be32_to_cpup(p++);
329 			READ_BUF(dummy32);
330 			len += XDR_QUADLEN(dummy32) << 2;
331 			READMEM(buf, dummy32);
332 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
333 			status = nfs_ok;
334 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
335 				;
336 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
337 				status = nfsd_map_name_to_gid(argp->rqstp,
338 						buf, dummy32, &ace->who_gid);
339 			else
340 				status = nfsd_map_name_to_uid(argp->rqstp,
341 						buf, dummy32, &ace->who_uid);
342 			if (status)
343 				return status;
344 		}
345 	} else
346 		*acl = NULL;
347 	if (bmval[1] & FATTR4_WORD1_MODE) {
348 		READ_BUF(4);
349 		len += 4;
350 		iattr->ia_mode = be32_to_cpup(p++);
351 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
352 		iattr->ia_valid |= ATTR_MODE;
353 	}
354 	if (bmval[1] & FATTR4_WORD1_OWNER) {
355 		READ_BUF(4);
356 		len += 4;
357 		dummy32 = be32_to_cpup(p++);
358 		READ_BUF(dummy32);
359 		len += (XDR_QUADLEN(dummy32) << 2);
360 		READMEM(buf, dummy32);
361 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
362 			return status;
363 		iattr->ia_valid |= ATTR_UID;
364 	}
365 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
366 		READ_BUF(4);
367 		len += 4;
368 		dummy32 = be32_to_cpup(p++);
369 		READ_BUF(dummy32);
370 		len += (XDR_QUADLEN(dummy32) << 2);
371 		READMEM(buf, dummy32);
372 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
373 			return status;
374 		iattr->ia_valid |= ATTR_GID;
375 	}
376 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
377 		READ_BUF(4);
378 		len += 4;
379 		dummy32 = be32_to_cpup(p++);
380 		switch (dummy32) {
381 		case NFS4_SET_TO_CLIENT_TIME:
382 			len += 12;
383 			status = nfsd4_decode_time(argp, &iattr->ia_atime);
384 			if (status)
385 				return status;
386 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
387 			break;
388 		case NFS4_SET_TO_SERVER_TIME:
389 			iattr->ia_valid |= ATTR_ATIME;
390 			break;
391 		default:
392 			goto xdr_error;
393 		}
394 	}
395 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
396 		READ_BUF(4);
397 		len += 4;
398 		dummy32 = be32_to_cpup(p++);
399 		switch (dummy32) {
400 		case NFS4_SET_TO_CLIENT_TIME:
401 			len += 12;
402 			status = nfsd4_decode_time(argp, &iattr->ia_mtime);
403 			if (status)
404 				return status;
405 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
406 			break;
407 		case NFS4_SET_TO_SERVER_TIME:
408 			iattr->ia_valid |= ATTR_MTIME;
409 			break;
410 		default:
411 			goto xdr_error;
412 		}
413 	}
414 
415 	label->len = 0;
416 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
417 	if (bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
418 		READ_BUF(4);
419 		len += 4;
420 		dummy32 = be32_to_cpup(p++); /* lfs: we don't use it */
421 		READ_BUF(4);
422 		len += 4;
423 		dummy32 = be32_to_cpup(p++); /* pi: we don't use it either */
424 		READ_BUF(4);
425 		len += 4;
426 		dummy32 = be32_to_cpup(p++);
427 		READ_BUF(dummy32);
428 		if (dummy32 > NFS4_MAXLABELLEN)
429 			return nfserr_badlabel;
430 		len += (XDR_QUADLEN(dummy32) << 2);
431 		READMEM(buf, dummy32);
432 		label->len = dummy32;
433 		label->data = svcxdr_dupstr(argp, buf, dummy32);
434 		if (!label->data)
435 			return nfserr_jukebox;
436 	}
437 #endif
438 
439 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
440 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
441 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2)
442 		READ_BUF(expected_len - len);
443 	else if (len != expected_len)
444 		goto xdr_error;
445 
446 	DECODE_TAIL;
447 }
448 
449 static __be32
450 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
451 {
452 	DECODE_HEAD;
453 
454 	READ_BUF(sizeof(stateid_t));
455 	sid->si_generation = be32_to_cpup(p++);
456 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
457 
458 	DECODE_TAIL;
459 }
460 
461 static __be32
462 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
463 {
464 	DECODE_HEAD;
465 
466 	READ_BUF(4);
467 	access->ac_req_access = be32_to_cpup(p++);
468 
469 	DECODE_TAIL;
470 }
471 
472 static __be32 nfsd4_decode_cb_sec(struct nfsd4_compoundargs *argp, struct nfsd4_cb_sec *cbs)
473 {
474 	DECODE_HEAD;
475 	u32 dummy, uid, gid;
476 	char *machine_name;
477 	int i;
478 	int nr_secflavs;
479 
480 	/* callback_sec_params4 */
481 	READ_BUF(4);
482 	nr_secflavs = be32_to_cpup(p++);
483 	if (nr_secflavs)
484 		cbs->flavor = (u32)(-1);
485 	else
486 		/* Is this legal? Be generous, take it to mean AUTH_NONE: */
487 		cbs->flavor = 0;
488 	for (i = 0; i < nr_secflavs; ++i) {
489 		READ_BUF(4);
490 		dummy = be32_to_cpup(p++);
491 		switch (dummy) {
492 		case RPC_AUTH_NULL:
493 			/* Nothing to read */
494 			if (cbs->flavor == (u32)(-1))
495 				cbs->flavor = RPC_AUTH_NULL;
496 			break;
497 		case RPC_AUTH_UNIX:
498 			READ_BUF(8);
499 			/* stamp */
500 			dummy = be32_to_cpup(p++);
501 
502 			/* machine name */
503 			dummy = be32_to_cpup(p++);
504 			READ_BUF(dummy);
505 			SAVEMEM(machine_name, dummy);
506 
507 			/* uid, gid */
508 			READ_BUF(8);
509 			uid = be32_to_cpup(p++);
510 			gid = be32_to_cpup(p++);
511 
512 			/* more gids */
513 			READ_BUF(4);
514 			dummy = be32_to_cpup(p++);
515 			READ_BUF(dummy * 4);
516 			if (cbs->flavor == (u32)(-1)) {
517 				kuid_t kuid = make_kuid(&init_user_ns, uid);
518 				kgid_t kgid = make_kgid(&init_user_ns, gid);
519 				if (uid_valid(kuid) && gid_valid(kgid)) {
520 					cbs->uid = kuid;
521 					cbs->gid = kgid;
522 					cbs->flavor = RPC_AUTH_UNIX;
523 				} else {
524 					dprintk("RPC_AUTH_UNIX with invalid"
525 						"uid or gid ignoring!\n");
526 				}
527 			}
528 			break;
529 		case RPC_AUTH_GSS:
530 			dprintk("RPC_AUTH_GSS callback secflavor "
531 				"not supported!\n");
532 			READ_BUF(8);
533 			/* gcbp_service */
534 			dummy = be32_to_cpup(p++);
535 			/* gcbp_handle_from_server */
536 			dummy = be32_to_cpup(p++);
537 			READ_BUF(dummy);
538 			p += XDR_QUADLEN(dummy);
539 			/* gcbp_handle_from_client */
540 			READ_BUF(4);
541 			dummy = be32_to_cpup(p++);
542 			READ_BUF(dummy);
543 			break;
544 		default:
545 			dprintk("Illegal callback secflavor\n");
546 			return nfserr_inval;
547 		}
548 	}
549 	DECODE_TAIL;
550 }
551 
552 static __be32 nfsd4_decode_backchannel_ctl(struct nfsd4_compoundargs *argp, struct nfsd4_backchannel_ctl *bc)
553 {
554 	DECODE_HEAD;
555 
556 	READ_BUF(4);
557 	bc->bc_cb_program = be32_to_cpup(p++);
558 	nfsd4_decode_cb_sec(argp, &bc->bc_cb_sec);
559 
560 	DECODE_TAIL;
561 }
562 
563 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
564 {
565 	DECODE_HEAD;
566 
567 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
568 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
569 	bcts->dir = be32_to_cpup(p++);
570 	/* XXX: skipping ctsa_use_conn_in_rdma_mode.  Perhaps Tom Tucker
571 	 * could help us figure out we should be using it. */
572 	DECODE_TAIL;
573 }
574 
575 static __be32
576 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
577 {
578 	DECODE_HEAD;
579 
580 	READ_BUF(4);
581 	close->cl_seqid = be32_to_cpup(p++);
582 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
583 
584 	DECODE_TAIL;
585 }
586 
587 
588 static __be32
589 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
590 {
591 	DECODE_HEAD;
592 
593 	READ_BUF(12);
594 	p = xdr_decode_hyper(p, &commit->co_offset);
595 	commit->co_count = be32_to_cpup(p++);
596 
597 	DECODE_TAIL;
598 }
599 
600 static __be32
601 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
602 {
603 	DECODE_HEAD;
604 
605 	READ_BUF(4);
606 	create->cr_type = be32_to_cpup(p++);
607 	switch (create->cr_type) {
608 	case NF4LNK:
609 		READ_BUF(4);
610 		create->cr_datalen = be32_to_cpup(p++);
611 		READ_BUF(create->cr_datalen);
612 		create->cr_data = svcxdr_dupstr(argp, p, create->cr_datalen);
613 		if (!create->cr_data)
614 			return nfserr_jukebox;
615 		break;
616 	case NF4BLK:
617 	case NF4CHR:
618 		READ_BUF(8);
619 		create->cr_specdata1 = be32_to_cpup(p++);
620 		create->cr_specdata2 = be32_to_cpup(p++);
621 		break;
622 	case NF4SOCK:
623 	case NF4FIFO:
624 	case NF4DIR:
625 	default:
626 		break;
627 	}
628 
629 	READ_BUF(4);
630 	create->cr_namelen = be32_to_cpup(p++);
631 	READ_BUF(create->cr_namelen);
632 	SAVEMEM(create->cr_name, create->cr_namelen);
633 	if ((status = check_filename(create->cr_name, create->cr_namelen)))
634 		return status;
635 
636 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
637 				    &create->cr_acl, &create->cr_label);
638 	if (status)
639 		goto out;
640 
641 	DECODE_TAIL;
642 }
643 
644 static inline __be32
645 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
646 {
647 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
648 }
649 
650 static inline __be32
651 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
652 {
653 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
654 }
655 
656 static __be32
657 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
658 {
659 	DECODE_HEAD;
660 
661 	READ_BUF(4);
662 	link->li_namelen = be32_to_cpup(p++);
663 	READ_BUF(link->li_namelen);
664 	SAVEMEM(link->li_name, link->li_namelen);
665 	if ((status = check_filename(link->li_name, link->li_namelen)))
666 		return status;
667 
668 	DECODE_TAIL;
669 }
670 
671 static __be32
672 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
673 {
674 	DECODE_HEAD;
675 
676 	/*
677 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
678 	*/
679 	READ_BUF(28);
680 	lock->lk_type = be32_to_cpup(p++);
681 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
682 		goto xdr_error;
683 	lock->lk_reclaim = be32_to_cpup(p++);
684 	p = xdr_decode_hyper(p, &lock->lk_offset);
685 	p = xdr_decode_hyper(p, &lock->lk_length);
686 	lock->lk_is_new = be32_to_cpup(p++);
687 
688 	if (lock->lk_is_new) {
689 		READ_BUF(4);
690 		lock->lk_new_open_seqid = be32_to_cpup(p++);
691 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
692 		if (status)
693 			return status;
694 		READ_BUF(8 + sizeof(clientid_t));
695 		lock->lk_new_lock_seqid = be32_to_cpup(p++);
696 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
697 		lock->lk_new_owner.len = be32_to_cpup(p++);
698 		READ_BUF(lock->lk_new_owner.len);
699 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
700 	} else {
701 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
702 		if (status)
703 			return status;
704 		READ_BUF(4);
705 		lock->lk_old_lock_seqid = be32_to_cpup(p++);
706 	}
707 
708 	DECODE_TAIL;
709 }
710 
711 static __be32
712 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
713 {
714 	DECODE_HEAD;
715 
716 	READ_BUF(32);
717 	lockt->lt_type = be32_to_cpup(p++);
718 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
719 		goto xdr_error;
720 	p = xdr_decode_hyper(p, &lockt->lt_offset);
721 	p = xdr_decode_hyper(p, &lockt->lt_length);
722 	COPYMEM(&lockt->lt_clientid, 8);
723 	lockt->lt_owner.len = be32_to_cpup(p++);
724 	READ_BUF(lockt->lt_owner.len);
725 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
726 
727 	DECODE_TAIL;
728 }
729 
730 static __be32
731 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
732 {
733 	DECODE_HEAD;
734 
735 	READ_BUF(8);
736 	locku->lu_type = be32_to_cpup(p++);
737 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
738 		goto xdr_error;
739 	locku->lu_seqid = be32_to_cpup(p++);
740 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
741 	if (status)
742 		return status;
743 	READ_BUF(16);
744 	p = xdr_decode_hyper(p, &locku->lu_offset);
745 	p = xdr_decode_hyper(p, &locku->lu_length);
746 
747 	DECODE_TAIL;
748 }
749 
750 static __be32
751 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
752 {
753 	DECODE_HEAD;
754 
755 	READ_BUF(4);
756 	lookup->lo_len = be32_to_cpup(p++);
757 	READ_BUF(lookup->lo_len);
758 	SAVEMEM(lookup->lo_name, lookup->lo_len);
759 	if ((status = check_filename(lookup->lo_name, lookup->lo_len)))
760 		return status;
761 
762 	DECODE_TAIL;
763 }
764 
765 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
766 {
767 	__be32 *p;
768 	u32 w;
769 
770 	READ_BUF(4);
771 	w = be32_to_cpup(p++);
772 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
773 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
774 	if (deleg_when)
775 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
776 
777 	switch (w & NFS4_SHARE_ACCESS_MASK) {
778 	case NFS4_SHARE_ACCESS_READ:
779 	case NFS4_SHARE_ACCESS_WRITE:
780 	case NFS4_SHARE_ACCESS_BOTH:
781 		break;
782 	default:
783 		return nfserr_bad_xdr;
784 	}
785 	w &= ~NFS4_SHARE_ACCESS_MASK;
786 	if (!w)
787 		return nfs_ok;
788 	if (!argp->minorversion)
789 		return nfserr_bad_xdr;
790 	switch (w & NFS4_SHARE_WANT_MASK) {
791 	case NFS4_SHARE_WANT_NO_PREFERENCE:
792 	case NFS4_SHARE_WANT_READ_DELEG:
793 	case NFS4_SHARE_WANT_WRITE_DELEG:
794 	case NFS4_SHARE_WANT_ANY_DELEG:
795 	case NFS4_SHARE_WANT_NO_DELEG:
796 	case NFS4_SHARE_WANT_CANCEL:
797 		break;
798 	default:
799 		return nfserr_bad_xdr;
800 	}
801 	w &= ~NFS4_SHARE_WANT_MASK;
802 	if (!w)
803 		return nfs_ok;
804 
805 	if (!deleg_when)	/* open_downgrade */
806 		return nfserr_inval;
807 	switch (w) {
808 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
809 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
810 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
811 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
812 		return nfs_ok;
813 	}
814 xdr_error:
815 	return nfserr_bad_xdr;
816 }
817 
818 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
819 {
820 	__be32 *p;
821 
822 	READ_BUF(4);
823 	*x = be32_to_cpup(p++);
824 	/* Note: unlinke access bits, deny bits may be zero. */
825 	if (*x & ~NFS4_SHARE_DENY_BOTH)
826 		return nfserr_bad_xdr;
827 	return nfs_ok;
828 xdr_error:
829 	return nfserr_bad_xdr;
830 }
831 
832 static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
833 {
834 	__be32 *p;
835 
836 	READ_BUF(4);
837 	o->len = be32_to_cpup(p++);
838 
839 	if (o->len == 0 || o->len > NFS4_OPAQUE_LIMIT)
840 		return nfserr_bad_xdr;
841 
842 	READ_BUF(o->len);
843 	SAVEMEM(o->data, o->len);
844 	return nfs_ok;
845 xdr_error:
846 	return nfserr_bad_xdr;
847 }
848 
849 static __be32
850 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
851 {
852 	DECODE_HEAD;
853 	u32 dummy;
854 
855 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
856 	open->op_iattr.ia_valid = 0;
857 	open->op_openowner = NULL;
858 
859 	open->op_xdr_error = 0;
860 	/* seqid, share_access, share_deny, clientid, ownerlen */
861 	READ_BUF(4);
862 	open->op_seqid = be32_to_cpup(p++);
863 	/* decode, yet ignore deleg_when until supported */
864 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
865 					   &open->op_deleg_want, &dummy);
866 	if (status)
867 		goto xdr_error;
868 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
869 	if (status)
870 		goto xdr_error;
871 	READ_BUF(sizeof(clientid_t));
872 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
873 	status = nfsd4_decode_opaque(argp, &open->op_owner);
874 	if (status)
875 		goto xdr_error;
876 	READ_BUF(4);
877 	open->op_create = be32_to_cpup(p++);
878 	switch (open->op_create) {
879 	case NFS4_OPEN_NOCREATE:
880 		break;
881 	case NFS4_OPEN_CREATE:
882 		READ_BUF(4);
883 		open->op_createmode = be32_to_cpup(p++);
884 		switch (open->op_createmode) {
885 		case NFS4_CREATE_UNCHECKED:
886 		case NFS4_CREATE_GUARDED:
887 			status = nfsd4_decode_fattr(argp, open->op_bmval,
888 				&open->op_iattr, &open->op_acl, &open->op_label);
889 			if (status)
890 				goto out;
891 			break;
892 		case NFS4_CREATE_EXCLUSIVE:
893 			READ_BUF(NFS4_VERIFIER_SIZE);
894 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
895 			break;
896 		case NFS4_CREATE_EXCLUSIVE4_1:
897 			if (argp->minorversion < 1)
898 				goto xdr_error;
899 			READ_BUF(NFS4_VERIFIER_SIZE);
900 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
901 			status = nfsd4_decode_fattr(argp, open->op_bmval,
902 				&open->op_iattr, &open->op_acl, &open->op_label);
903 			if (status)
904 				goto out;
905 			break;
906 		default:
907 			goto xdr_error;
908 		}
909 		break;
910 	default:
911 		goto xdr_error;
912 	}
913 
914 	/* open_claim */
915 	READ_BUF(4);
916 	open->op_claim_type = be32_to_cpup(p++);
917 	switch (open->op_claim_type) {
918 	case NFS4_OPEN_CLAIM_NULL:
919 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
920 		READ_BUF(4);
921 		open->op_fname.len = be32_to_cpup(p++);
922 		READ_BUF(open->op_fname.len);
923 		SAVEMEM(open->op_fname.data, open->op_fname.len);
924 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
925 			return status;
926 		break;
927 	case NFS4_OPEN_CLAIM_PREVIOUS:
928 		READ_BUF(4);
929 		open->op_delegate_type = be32_to_cpup(p++);
930 		break;
931 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
932 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
933 		if (status)
934 			return status;
935 		READ_BUF(4);
936 		open->op_fname.len = be32_to_cpup(p++);
937 		READ_BUF(open->op_fname.len);
938 		SAVEMEM(open->op_fname.data, open->op_fname.len);
939 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
940 			return status;
941 		break;
942 	case NFS4_OPEN_CLAIM_FH:
943 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
944 		if (argp->minorversion < 1)
945 			goto xdr_error;
946 		/* void */
947 		break;
948 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
949 		if (argp->minorversion < 1)
950 			goto xdr_error;
951 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
952 		if (status)
953 			return status;
954 		break;
955 	default:
956 		goto xdr_error;
957 	}
958 
959 	DECODE_TAIL;
960 }
961 
962 static __be32
963 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
964 {
965 	DECODE_HEAD;
966 
967 	if (argp->minorversion >= 1)
968 		return nfserr_notsupp;
969 
970 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
971 	if (status)
972 		return status;
973 	READ_BUF(4);
974 	open_conf->oc_seqid = be32_to_cpup(p++);
975 
976 	DECODE_TAIL;
977 }
978 
979 static __be32
980 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
981 {
982 	DECODE_HEAD;
983 
984 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
985 	if (status)
986 		return status;
987 	READ_BUF(4);
988 	open_down->od_seqid = be32_to_cpup(p++);
989 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
990 					   &open_down->od_deleg_want, NULL);
991 	if (status)
992 		return status;
993 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
994 	if (status)
995 		return status;
996 	DECODE_TAIL;
997 }
998 
999 static __be32
1000 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
1001 {
1002 	DECODE_HEAD;
1003 
1004 	READ_BUF(4);
1005 	putfh->pf_fhlen = be32_to_cpup(p++);
1006 	if (putfh->pf_fhlen > NFS4_FHSIZE)
1007 		goto xdr_error;
1008 	READ_BUF(putfh->pf_fhlen);
1009 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
1010 
1011 	DECODE_TAIL;
1012 }
1013 
1014 static __be32
1015 nfsd4_decode_putpubfh(struct nfsd4_compoundargs *argp, void *p)
1016 {
1017 	if (argp->minorversion == 0)
1018 		return nfs_ok;
1019 	return nfserr_notsupp;
1020 }
1021 
1022 static __be32
1023 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
1024 {
1025 	DECODE_HEAD;
1026 
1027 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
1028 	if (status)
1029 		return status;
1030 	READ_BUF(12);
1031 	p = xdr_decode_hyper(p, &read->rd_offset);
1032 	read->rd_length = be32_to_cpup(p++);
1033 
1034 	DECODE_TAIL;
1035 }
1036 
1037 static __be32
1038 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
1039 {
1040 	DECODE_HEAD;
1041 
1042 	READ_BUF(24);
1043 	p = xdr_decode_hyper(p, &readdir->rd_cookie);
1044 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
1045 	readdir->rd_dircount = be32_to_cpup(p++);
1046 	readdir->rd_maxcount = be32_to_cpup(p++);
1047 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
1048 		goto out;
1049 
1050 	DECODE_TAIL;
1051 }
1052 
1053 static __be32
1054 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
1055 {
1056 	DECODE_HEAD;
1057 
1058 	READ_BUF(4);
1059 	remove->rm_namelen = be32_to_cpup(p++);
1060 	READ_BUF(remove->rm_namelen);
1061 	SAVEMEM(remove->rm_name, remove->rm_namelen);
1062 	if ((status = check_filename(remove->rm_name, remove->rm_namelen)))
1063 		return status;
1064 
1065 	DECODE_TAIL;
1066 }
1067 
1068 static __be32
1069 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
1070 {
1071 	DECODE_HEAD;
1072 
1073 	READ_BUF(4);
1074 	rename->rn_snamelen = be32_to_cpup(p++);
1075 	READ_BUF(rename->rn_snamelen);
1076 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1077 	READ_BUF(4);
1078 	rename->rn_tnamelen = be32_to_cpup(p++);
1079 	READ_BUF(rename->rn_tnamelen);
1080 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1081 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1082 		return status;
1083 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1084 		return status;
1085 
1086 	DECODE_TAIL;
1087 }
1088 
1089 static __be32
1090 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1091 {
1092 	DECODE_HEAD;
1093 
1094 	if (argp->minorversion >= 1)
1095 		return nfserr_notsupp;
1096 
1097 	READ_BUF(sizeof(clientid_t));
1098 	COPYMEM(clientid, sizeof(clientid_t));
1099 
1100 	DECODE_TAIL;
1101 }
1102 
1103 static __be32
1104 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1105 		     struct nfsd4_secinfo *secinfo)
1106 {
1107 	DECODE_HEAD;
1108 
1109 	READ_BUF(4);
1110 	secinfo->si_namelen = be32_to_cpup(p++);
1111 	READ_BUF(secinfo->si_namelen);
1112 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1113 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1114 	if (status)
1115 		return status;
1116 	DECODE_TAIL;
1117 }
1118 
1119 static __be32
1120 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1121 		     struct nfsd4_secinfo_no_name *sin)
1122 {
1123 	DECODE_HEAD;
1124 
1125 	READ_BUF(4);
1126 	sin->sin_style = be32_to_cpup(p++);
1127 	DECODE_TAIL;
1128 }
1129 
1130 static __be32
1131 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1132 {
1133 	__be32 status;
1134 
1135 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1136 	if (status)
1137 		return status;
1138 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1139 				  &setattr->sa_acl, &setattr->sa_label);
1140 }
1141 
1142 static __be32
1143 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1144 {
1145 	DECODE_HEAD;
1146 
1147 	if (argp->minorversion >= 1)
1148 		return nfserr_notsupp;
1149 
1150 	READ_BUF(NFS4_VERIFIER_SIZE);
1151 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1152 
1153 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1154 	if (status)
1155 		return nfserr_bad_xdr;
1156 	READ_BUF(8);
1157 	setclientid->se_callback_prog = be32_to_cpup(p++);
1158 	setclientid->se_callback_netid_len = be32_to_cpup(p++);
1159 	READ_BUF(setclientid->se_callback_netid_len);
1160 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1161 	READ_BUF(4);
1162 	setclientid->se_callback_addr_len = be32_to_cpup(p++);
1163 
1164 	READ_BUF(setclientid->se_callback_addr_len);
1165 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1166 	READ_BUF(4);
1167 	setclientid->se_callback_ident = be32_to_cpup(p++);
1168 
1169 	DECODE_TAIL;
1170 }
1171 
1172 static __be32
1173 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1174 {
1175 	DECODE_HEAD;
1176 
1177 	if (argp->minorversion >= 1)
1178 		return nfserr_notsupp;
1179 
1180 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1181 	COPYMEM(&scd_c->sc_clientid, 8);
1182 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1183 
1184 	DECODE_TAIL;
1185 }
1186 
1187 /* Also used for NVERIFY */
1188 static __be32
1189 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1190 {
1191 	DECODE_HEAD;
1192 
1193 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1194 		goto out;
1195 
1196 	/* For convenience's sake, we compare raw xdr'd attributes in
1197 	 * nfsd4_proc_verify */
1198 
1199 	READ_BUF(4);
1200 	verify->ve_attrlen = be32_to_cpup(p++);
1201 	READ_BUF(verify->ve_attrlen);
1202 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1203 
1204 	DECODE_TAIL;
1205 }
1206 
1207 static __be32
1208 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1209 {
1210 	int avail;
1211 	int len;
1212 	DECODE_HEAD;
1213 
1214 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1215 	if (status)
1216 		return status;
1217 	READ_BUF(16);
1218 	p = xdr_decode_hyper(p, &write->wr_offset);
1219 	write->wr_stable_how = be32_to_cpup(p++);
1220 	if (write->wr_stable_how > 2)
1221 		goto xdr_error;
1222 	write->wr_buflen = be32_to_cpup(p++);
1223 
1224 	/* Sorry .. no magic macros for this.. *
1225 	 * READ_BUF(write->wr_buflen);
1226 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1227 	 */
1228 	avail = (char*)argp->end - (char*)argp->p;
1229 	if (avail + argp->pagelen < write->wr_buflen) {
1230 		dprintk("NFSD: xdr error (%s:%d)\n",
1231 				__FILE__, __LINE__);
1232 		goto xdr_error;
1233 	}
1234 	write->wr_head.iov_base = p;
1235 	write->wr_head.iov_len = avail;
1236 	write->wr_pagelist = argp->pagelist;
1237 
1238 	len = XDR_QUADLEN(write->wr_buflen) << 2;
1239 	if (len >= avail) {
1240 		int pages;
1241 
1242 		len -= avail;
1243 
1244 		pages = len >> PAGE_SHIFT;
1245 		argp->pagelist += pages;
1246 		argp->pagelen -= pages * PAGE_SIZE;
1247 		len -= pages * PAGE_SIZE;
1248 
1249 		argp->p = (__be32 *)page_address(argp->pagelist[0]);
1250 		argp->pagelist++;
1251 		argp->end = argp->p + XDR_QUADLEN(PAGE_SIZE);
1252 	}
1253 	argp->p += XDR_QUADLEN(len);
1254 
1255 	DECODE_TAIL;
1256 }
1257 
1258 static __be32
1259 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1260 {
1261 	DECODE_HEAD;
1262 
1263 	if (argp->minorversion >= 1)
1264 		return nfserr_notsupp;
1265 
1266 	READ_BUF(12);
1267 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1268 	rlockowner->rl_owner.len = be32_to_cpup(p++);
1269 	READ_BUF(rlockowner->rl_owner.len);
1270 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1271 
1272 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1273 		return nfserr_inval;
1274 	DECODE_TAIL;
1275 }
1276 
1277 static __be32
1278 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1279 			 struct nfsd4_exchange_id *exid)
1280 {
1281 	int dummy, tmp;
1282 	DECODE_HEAD;
1283 
1284 	READ_BUF(NFS4_VERIFIER_SIZE);
1285 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1286 
1287 	status = nfsd4_decode_opaque(argp, &exid->clname);
1288 	if (status)
1289 		return nfserr_bad_xdr;
1290 
1291 	READ_BUF(4);
1292 	exid->flags = be32_to_cpup(p++);
1293 
1294 	/* Ignore state_protect4_a */
1295 	READ_BUF(4);
1296 	exid->spa_how = be32_to_cpup(p++);
1297 	switch (exid->spa_how) {
1298 	case SP4_NONE:
1299 		break;
1300 	case SP4_MACH_CRED:
1301 		/* spo_must_enforce */
1302 		READ_BUF(4);
1303 		dummy = be32_to_cpup(p++);
1304 		READ_BUF(dummy * 4);
1305 		p += dummy;
1306 
1307 		/* spo_must_allow */
1308 		READ_BUF(4);
1309 		dummy = be32_to_cpup(p++);
1310 		READ_BUF(dummy * 4);
1311 		p += dummy;
1312 		break;
1313 	case SP4_SSV:
1314 		/* ssp_ops */
1315 		READ_BUF(4);
1316 		dummy = be32_to_cpup(p++);
1317 		READ_BUF(dummy * 4);
1318 		p += dummy;
1319 
1320 		READ_BUF(4);
1321 		dummy = be32_to_cpup(p++);
1322 		READ_BUF(dummy * 4);
1323 		p += dummy;
1324 
1325 		/* ssp_hash_algs<> */
1326 		READ_BUF(4);
1327 		tmp = be32_to_cpup(p++);
1328 		while (tmp--) {
1329 			READ_BUF(4);
1330 			dummy = be32_to_cpup(p++);
1331 			READ_BUF(dummy);
1332 			p += XDR_QUADLEN(dummy);
1333 		}
1334 
1335 		/* ssp_encr_algs<> */
1336 		READ_BUF(4);
1337 		tmp = be32_to_cpup(p++);
1338 		while (tmp--) {
1339 			READ_BUF(4);
1340 			dummy = be32_to_cpup(p++);
1341 			READ_BUF(dummy);
1342 			p += XDR_QUADLEN(dummy);
1343 		}
1344 
1345 		/* ssp_window and ssp_num_gss_handles */
1346 		READ_BUF(8);
1347 		dummy = be32_to_cpup(p++);
1348 		dummy = be32_to_cpup(p++);
1349 		break;
1350 	default:
1351 		goto xdr_error;
1352 	}
1353 
1354 	/* Ignore Implementation ID */
1355 	READ_BUF(4);    /* nfs_impl_id4 array length */
1356 	dummy = be32_to_cpup(p++);
1357 
1358 	if (dummy > 1)
1359 		goto xdr_error;
1360 
1361 	if (dummy == 1) {
1362 		/* nii_domain */
1363 		READ_BUF(4);
1364 		dummy = be32_to_cpup(p++);
1365 		READ_BUF(dummy);
1366 		p += XDR_QUADLEN(dummy);
1367 
1368 		/* nii_name */
1369 		READ_BUF(4);
1370 		dummy = be32_to_cpup(p++);
1371 		READ_BUF(dummy);
1372 		p += XDR_QUADLEN(dummy);
1373 
1374 		/* nii_date */
1375 		READ_BUF(12);
1376 		p += 3;
1377 	}
1378 	DECODE_TAIL;
1379 }
1380 
1381 static __be32
1382 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1383 			    struct nfsd4_create_session *sess)
1384 {
1385 	DECODE_HEAD;
1386 	u32 dummy;
1387 
1388 	READ_BUF(16);
1389 	COPYMEM(&sess->clientid, 8);
1390 	sess->seqid = be32_to_cpup(p++);
1391 	sess->flags = be32_to_cpup(p++);
1392 
1393 	/* Fore channel attrs */
1394 	READ_BUF(28);
1395 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1396 	sess->fore_channel.maxreq_sz = be32_to_cpup(p++);
1397 	sess->fore_channel.maxresp_sz = be32_to_cpup(p++);
1398 	sess->fore_channel.maxresp_cached = be32_to_cpup(p++);
1399 	sess->fore_channel.maxops = be32_to_cpup(p++);
1400 	sess->fore_channel.maxreqs = be32_to_cpup(p++);
1401 	sess->fore_channel.nr_rdma_attrs = be32_to_cpup(p++);
1402 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1403 		READ_BUF(4);
1404 		sess->fore_channel.rdma_attrs = be32_to_cpup(p++);
1405 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1406 		dprintk("Too many fore channel attr bitmaps!\n");
1407 		goto xdr_error;
1408 	}
1409 
1410 	/* Back channel attrs */
1411 	READ_BUF(28);
1412 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1413 	sess->back_channel.maxreq_sz = be32_to_cpup(p++);
1414 	sess->back_channel.maxresp_sz = be32_to_cpup(p++);
1415 	sess->back_channel.maxresp_cached = be32_to_cpup(p++);
1416 	sess->back_channel.maxops = be32_to_cpup(p++);
1417 	sess->back_channel.maxreqs = be32_to_cpup(p++);
1418 	sess->back_channel.nr_rdma_attrs = be32_to_cpup(p++);
1419 	if (sess->back_channel.nr_rdma_attrs == 1) {
1420 		READ_BUF(4);
1421 		sess->back_channel.rdma_attrs = be32_to_cpup(p++);
1422 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1423 		dprintk("Too many back channel attr bitmaps!\n");
1424 		goto xdr_error;
1425 	}
1426 
1427 	READ_BUF(4);
1428 	sess->callback_prog = be32_to_cpup(p++);
1429 	nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1430 	DECODE_TAIL;
1431 }
1432 
1433 static __be32
1434 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1435 			     struct nfsd4_destroy_session *destroy_session)
1436 {
1437 	DECODE_HEAD;
1438 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1439 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1440 
1441 	DECODE_TAIL;
1442 }
1443 
1444 static __be32
1445 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1446 			  struct nfsd4_free_stateid *free_stateid)
1447 {
1448 	DECODE_HEAD;
1449 
1450 	READ_BUF(sizeof(stateid_t));
1451 	free_stateid->fr_stateid.si_generation = be32_to_cpup(p++);
1452 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1453 
1454 	DECODE_TAIL;
1455 }
1456 
1457 static __be32
1458 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1459 		      struct nfsd4_sequence *seq)
1460 {
1461 	DECODE_HEAD;
1462 
1463 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1464 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1465 	seq->seqid = be32_to_cpup(p++);
1466 	seq->slotid = be32_to_cpup(p++);
1467 	seq->maxslots = be32_to_cpup(p++);
1468 	seq->cachethis = be32_to_cpup(p++);
1469 
1470 	DECODE_TAIL;
1471 }
1472 
1473 static __be32
1474 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1475 {
1476 	int i;
1477 	__be32 *p, status;
1478 	struct nfsd4_test_stateid_id *stateid;
1479 
1480 	READ_BUF(4);
1481 	test_stateid->ts_num_ids = ntohl(*p++);
1482 
1483 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1484 
1485 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1486 		stateid = svcxdr_tmpalloc(argp, sizeof(*stateid));
1487 		if (!stateid) {
1488 			status = nfserrno(-ENOMEM);
1489 			goto out;
1490 		}
1491 
1492 		INIT_LIST_HEAD(&stateid->ts_id_list);
1493 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1494 
1495 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1496 		if (status)
1497 			goto out;
1498 	}
1499 
1500 	status = 0;
1501 out:
1502 	return status;
1503 xdr_error:
1504 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1505 	status = nfserr_bad_xdr;
1506 	goto out;
1507 }
1508 
1509 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1510 {
1511 	DECODE_HEAD;
1512 
1513 	READ_BUF(8);
1514 	COPYMEM(&dc->clientid, 8);
1515 
1516 	DECODE_TAIL;
1517 }
1518 
1519 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1520 {
1521 	DECODE_HEAD;
1522 
1523 	READ_BUF(4);
1524 	rc->rca_one_fs = be32_to_cpup(p++);
1525 
1526 	DECODE_TAIL;
1527 }
1528 
1529 #ifdef CONFIG_NFSD_PNFS
1530 static __be32
1531 nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp,
1532 		struct nfsd4_getdeviceinfo *gdev)
1533 {
1534 	DECODE_HEAD;
1535 	u32 num, i;
1536 
1537 	READ_BUF(sizeof(struct nfsd4_deviceid) + 3 * 4);
1538 	COPYMEM(&gdev->gd_devid, sizeof(struct nfsd4_deviceid));
1539 	gdev->gd_layout_type = be32_to_cpup(p++);
1540 	gdev->gd_maxcount = be32_to_cpup(p++);
1541 	num = be32_to_cpup(p++);
1542 	if (num) {
1543 		READ_BUF(4 * num);
1544 		gdev->gd_notify_types = be32_to_cpup(p++);
1545 		for (i = 1; i < num; i++) {
1546 			if (be32_to_cpup(p++)) {
1547 				status = nfserr_inval;
1548 				goto out;
1549 			}
1550 		}
1551 	}
1552 	DECODE_TAIL;
1553 }
1554 
1555 static __be32
1556 nfsd4_decode_layoutget(struct nfsd4_compoundargs *argp,
1557 		struct nfsd4_layoutget *lgp)
1558 {
1559 	DECODE_HEAD;
1560 
1561 	READ_BUF(36);
1562 	lgp->lg_signal = be32_to_cpup(p++);
1563 	lgp->lg_layout_type = be32_to_cpup(p++);
1564 	lgp->lg_seg.iomode = be32_to_cpup(p++);
1565 	p = xdr_decode_hyper(p, &lgp->lg_seg.offset);
1566 	p = xdr_decode_hyper(p, &lgp->lg_seg.length);
1567 	p = xdr_decode_hyper(p, &lgp->lg_minlength);
1568 
1569 	status = nfsd4_decode_stateid(argp, &lgp->lg_sid);
1570 	if (status)
1571 		return status;
1572 
1573 	READ_BUF(4);
1574 	lgp->lg_maxcount = be32_to_cpup(p++);
1575 
1576 	DECODE_TAIL;
1577 }
1578 
1579 static __be32
1580 nfsd4_decode_layoutcommit(struct nfsd4_compoundargs *argp,
1581 		struct nfsd4_layoutcommit *lcp)
1582 {
1583 	DECODE_HEAD;
1584 	u32 timechange;
1585 
1586 	READ_BUF(20);
1587 	p = xdr_decode_hyper(p, &lcp->lc_seg.offset);
1588 	p = xdr_decode_hyper(p, &lcp->lc_seg.length);
1589 	lcp->lc_reclaim = be32_to_cpup(p++);
1590 
1591 	status = nfsd4_decode_stateid(argp, &lcp->lc_sid);
1592 	if (status)
1593 		return status;
1594 
1595 	READ_BUF(4);
1596 	lcp->lc_newoffset = be32_to_cpup(p++);
1597 	if (lcp->lc_newoffset) {
1598 		READ_BUF(8);
1599 		p = xdr_decode_hyper(p, &lcp->lc_last_wr);
1600 	} else
1601 		lcp->lc_last_wr = 0;
1602 	READ_BUF(4);
1603 	timechange = be32_to_cpup(p++);
1604 	if (timechange) {
1605 		status = nfsd4_decode_time(argp, &lcp->lc_mtime);
1606 		if (status)
1607 			return status;
1608 	} else {
1609 		lcp->lc_mtime.tv_nsec = UTIME_NOW;
1610 	}
1611 	READ_BUF(8);
1612 	lcp->lc_layout_type = be32_to_cpup(p++);
1613 
1614 	/*
1615 	 * Save the layout update in XDR format and let the layout driver deal
1616 	 * with it later.
1617 	 */
1618 	lcp->lc_up_len = be32_to_cpup(p++);
1619 	if (lcp->lc_up_len > 0) {
1620 		READ_BUF(lcp->lc_up_len);
1621 		READMEM(lcp->lc_up_layout, lcp->lc_up_len);
1622 	}
1623 
1624 	DECODE_TAIL;
1625 }
1626 
1627 static __be32
1628 nfsd4_decode_layoutreturn(struct nfsd4_compoundargs *argp,
1629 		struct nfsd4_layoutreturn *lrp)
1630 {
1631 	DECODE_HEAD;
1632 
1633 	READ_BUF(16);
1634 	lrp->lr_reclaim = be32_to_cpup(p++);
1635 	lrp->lr_layout_type = be32_to_cpup(p++);
1636 	lrp->lr_seg.iomode = be32_to_cpup(p++);
1637 	lrp->lr_return_type = be32_to_cpup(p++);
1638 	if (lrp->lr_return_type == RETURN_FILE) {
1639 		READ_BUF(16);
1640 		p = xdr_decode_hyper(p, &lrp->lr_seg.offset);
1641 		p = xdr_decode_hyper(p, &lrp->lr_seg.length);
1642 
1643 		status = nfsd4_decode_stateid(argp, &lrp->lr_sid);
1644 		if (status)
1645 			return status;
1646 
1647 		READ_BUF(4);
1648 		lrp->lrf_body_len = be32_to_cpup(p++);
1649 		if (lrp->lrf_body_len > 0) {
1650 			READ_BUF(lrp->lrf_body_len);
1651 			READMEM(lrp->lrf_body, lrp->lrf_body_len);
1652 		}
1653 	} else {
1654 		lrp->lr_seg.offset = 0;
1655 		lrp->lr_seg.length = NFS4_MAX_UINT64;
1656 	}
1657 
1658 	DECODE_TAIL;
1659 }
1660 #endif /* CONFIG_NFSD_PNFS */
1661 
1662 static __be32
1663 nfsd4_decode_fallocate(struct nfsd4_compoundargs *argp,
1664 		       struct nfsd4_fallocate *fallocate)
1665 {
1666 	DECODE_HEAD;
1667 
1668 	status = nfsd4_decode_stateid(argp, &fallocate->falloc_stateid);
1669 	if (status)
1670 		return status;
1671 
1672 	READ_BUF(16);
1673 	p = xdr_decode_hyper(p, &fallocate->falloc_offset);
1674 	xdr_decode_hyper(p, &fallocate->falloc_length);
1675 
1676 	DECODE_TAIL;
1677 }
1678 
1679 static __be32
1680 nfsd4_decode_clone(struct nfsd4_compoundargs *argp, struct nfsd4_clone *clone)
1681 {
1682 	DECODE_HEAD;
1683 
1684 	status = nfsd4_decode_stateid(argp, &clone->cl_src_stateid);
1685 	if (status)
1686 		return status;
1687 	status = nfsd4_decode_stateid(argp, &clone->cl_dst_stateid);
1688 	if (status)
1689 		return status;
1690 
1691 	READ_BUF(8 + 8 + 8);
1692 	p = xdr_decode_hyper(p, &clone->cl_src_pos);
1693 	p = xdr_decode_hyper(p, &clone->cl_dst_pos);
1694 	p = xdr_decode_hyper(p, &clone->cl_count);
1695 	DECODE_TAIL;
1696 }
1697 
1698 static __be32
1699 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
1700 {
1701 	DECODE_HEAD;
1702 
1703 	status = nfsd4_decode_stateid(argp, &seek->seek_stateid);
1704 	if (status)
1705 		return status;
1706 
1707 	READ_BUF(8 + 4);
1708 	p = xdr_decode_hyper(p, &seek->seek_offset);
1709 	seek->seek_whence = be32_to_cpup(p);
1710 
1711 	DECODE_TAIL;
1712 }
1713 
1714 static __be32
1715 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1716 {
1717 	return nfs_ok;
1718 }
1719 
1720 static __be32
1721 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1722 {
1723 	return nfserr_notsupp;
1724 }
1725 
1726 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1727 
1728 static nfsd4_dec nfsd4_dec_ops[] = {
1729 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1730 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1731 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1732 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1733 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1734 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1735 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1736 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1737 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1738 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1739 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1740 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1741 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1742 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1743 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1744 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1745 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1746 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1747 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1748 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1749 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_putpubfh,
1750 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1751 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1752 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1753 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1754 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1755 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1756 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1757 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1758 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1759 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1760 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1761 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1762 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1763 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1764 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1765 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1766 
1767 	/* new operations for NFSv4.1 */
1768 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_backchannel_ctl,
1769 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1770 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1771 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1772 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1773 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
1774 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1775 #ifdef CONFIG_NFSD_PNFS
1776 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_getdeviceinfo,
1777 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1778 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_layoutcommit,
1779 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_layoutget,
1780 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_layoutreturn,
1781 #else
1782 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1783 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1784 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1785 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1786 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1787 #endif
1788 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1789 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1790 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1791 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
1792 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1793 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
1794 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1795 
1796 	/* new operations for NFSv4.2 */
1797 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1798 	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_notsupp,
1799 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
1800 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1801 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1802 	[OP_LAYOUTERROR]	= (nfsd4_dec)nfsd4_decode_notsupp,
1803 	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1804 	[OP_OFFLOAD_CANCEL]	= (nfsd4_dec)nfsd4_decode_notsupp,
1805 	[OP_OFFLOAD_STATUS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1806 	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_notsupp,
1807 	[OP_SEEK]		= (nfsd4_dec)nfsd4_decode_seek,
1808 	[OP_WRITE_SAME]		= (nfsd4_dec)nfsd4_decode_notsupp,
1809 	[OP_CLONE]		= (nfsd4_dec)nfsd4_decode_clone,
1810 };
1811 
1812 static inline bool
1813 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
1814 {
1815 	if (op->opnum < FIRST_NFS4_OP)
1816 		return false;
1817 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
1818 		return false;
1819 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
1820 		return false;
1821 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
1822 		return false;
1823 	return true;
1824 }
1825 
1826 static __be32
1827 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1828 {
1829 	DECODE_HEAD;
1830 	struct nfsd4_op *op;
1831 	bool cachethis = false;
1832 	int auth_slack= argp->rqstp->rq_auth_slack;
1833 	int max_reply = auth_slack + 8; /* opcnt, status */
1834 	int readcount = 0;
1835 	int readbytes = 0;
1836 	int i;
1837 
1838 	READ_BUF(4);
1839 	argp->taglen = be32_to_cpup(p++);
1840 	READ_BUF(argp->taglen);
1841 	SAVEMEM(argp->tag, argp->taglen);
1842 	READ_BUF(8);
1843 	argp->minorversion = be32_to_cpup(p++);
1844 	argp->opcnt = be32_to_cpup(p++);
1845 	max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
1846 
1847 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1848 		goto xdr_error;
1849 	if (argp->opcnt > 100)
1850 		goto xdr_error;
1851 
1852 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1853 		argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1854 		if (!argp->ops) {
1855 			argp->ops = argp->iops;
1856 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1857 			goto xdr_error;
1858 		}
1859 	}
1860 
1861 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
1862 		argp->opcnt = 0;
1863 
1864 	for (i = 0; i < argp->opcnt; i++) {
1865 		op = &argp->ops[i];
1866 		op->replay = NULL;
1867 
1868 		READ_BUF(4);
1869 		op->opnum = be32_to_cpup(p++);
1870 
1871 		if (nfsd4_opnum_in_range(argp, op))
1872 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
1873 		else {
1874 			op->opnum = OP_ILLEGAL;
1875 			op->status = nfserr_op_illegal;
1876 		}
1877 		/*
1878 		 * We'll try to cache the result in the DRC if any one
1879 		 * op in the compound wants to be cached:
1880 		 */
1881 		cachethis |= nfsd4_cache_this_op(op);
1882 
1883 		if (op->opnum == OP_READ) {
1884 			readcount++;
1885 			readbytes += nfsd4_max_reply(argp->rqstp, op);
1886 		} else
1887 			max_reply += nfsd4_max_reply(argp->rqstp, op);
1888 		/*
1889 		 * OP_LOCK may return a conflicting lock.  (Special case
1890 		 * because it will just skip encoding this if it runs
1891 		 * out of xdr buffer space, and it is the only operation
1892 		 * that behaves this way.)
1893 		 */
1894 		if (op->opnum == OP_LOCK)
1895 			max_reply += NFS4_OPAQUE_LIMIT;
1896 
1897 		if (op->status) {
1898 			argp->opcnt = i+1;
1899 			break;
1900 		}
1901 	}
1902 	/* Sessions make the DRC unnecessary: */
1903 	if (argp->minorversion)
1904 		cachethis = false;
1905 	svc_reserve(argp->rqstp, max_reply + readbytes);
1906 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1907 
1908 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
1909 		clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
1910 
1911 	DECODE_TAIL;
1912 }
1913 
1914 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode)
1915 {
1916 	if (IS_I_VERSION(inode)) {
1917 		p = xdr_encode_hyper(p, inode->i_version);
1918 	} else {
1919 		*p++ = cpu_to_be32(stat->ctime.tv_sec);
1920 		*p++ = cpu_to_be32(stat->ctime.tv_nsec);
1921 	}
1922 	return p;
1923 }
1924 
1925 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
1926 {
1927 	*p++ = cpu_to_be32(c->atomic);
1928 	if (c->change_supported) {
1929 		p = xdr_encode_hyper(p, c->before_change);
1930 		p = xdr_encode_hyper(p, c->after_change);
1931 	} else {
1932 		*p++ = cpu_to_be32(c->before_ctime_sec);
1933 		*p++ = cpu_to_be32(c->before_ctime_nsec);
1934 		*p++ = cpu_to_be32(c->after_ctime_sec);
1935 		*p++ = cpu_to_be32(c->after_ctime_nsec);
1936 	}
1937 	return p;
1938 }
1939 
1940 /* Encode as an array of strings the string given with components
1941  * separated @sep, escaped with esc_enter and esc_exit.
1942  */
1943 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
1944 					  char *components, char esc_enter,
1945 					  char esc_exit)
1946 {
1947 	__be32 *p;
1948 	__be32 pathlen;
1949 	int pathlen_offset;
1950 	int strlen, count=0;
1951 	char *str, *end, *next;
1952 
1953 	dprintk("nfsd4_encode_components(%s)\n", components);
1954 
1955 	pathlen_offset = xdr->buf->len;
1956 	p = xdr_reserve_space(xdr, 4);
1957 	if (!p)
1958 		return nfserr_resource;
1959 	p++; /* We will fill this in with @count later */
1960 
1961 	end = str = components;
1962 	while (*end) {
1963 		bool found_esc = false;
1964 
1965 		/* try to parse as esc_start, ..., esc_end, sep */
1966 		if (*str == esc_enter) {
1967 			for (; *end && (*end != esc_exit); end++)
1968 				/* find esc_exit or end of string */;
1969 			next = end + 1;
1970 			if (*end && (!*next || *next == sep)) {
1971 				str++;
1972 				found_esc = true;
1973 			}
1974 		}
1975 
1976 		if (!found_esc)
1977 			for (; *end && (*end != sep); end++)
1978 				/* find sep or end of string */;
1979 
1980 		strlen = end - str;
1981 		if (strlen) {
1982 			p = xdr_reserve_space(xdr, strlen + 4);
1983 			if (!p)
1984 				return nfserr_resource;
1985 			p = xdr_encode_opaque(p, str, strlen);
1986 			count++;
1987 		}
1988 		else
1989 			end++;
1990 		if (found_esc)
1991 			end = next;
1992 
1993 		str = end;
1994 	}
1995 	pathlen = htonl(count);
1996 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
1997 	return 0;
1998 }
1999 
2000 /* Encode as an array of strings the string given with components
2001  * separated @sep.
2002  */
2003 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
2004 				      char *components)
2005 {
2006 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
2007 }
2008 
2009 /*
2010  * encode a location element of a fs_locations structure
2011  */
2012 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
2013 					struct nfsd4_fs_location *location)
2014 {
2015 	__be32 status;
2016 
2017 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
2018 						'[', ']');
2019 	if (status)
2020 		return status;
2021 	status = nfsd4_encode_components(xdr, '/', location->path);
2022 	if (status)
2023 		return status;
2024 	return 0;
2025 }
2026 
2027 /*
2028  * Encode a path in RFC3530 'pathname4' format
2029  */
2030 static __be32 nfsd4_encode_path(struct xdr_stream *xdr,
2031 				const struct path *root,
2032 				const struct path *path)
2033 {
2034 	struct path cur = *path;
2035 	__be32 *p;
2036 	struct dentry **components = NULL;
2037 	unsigned int ncomponents = 0;
2038 	__be32 err = nfserr_jukebox;
2039 
2040 	dprintk("nfsd4_encode_components(");
2041 
2042 	path_get(&cur);
2043 	/* First walk the path up to the nfsd root, and store the
2044 	 * dentries/path components in an array.
2045 	 */
2046 	for (;;) {
2047 		if (path_equal(&cur, root))
2048 			break;
2049 		if (cur.dentry == cur.mnt->mnt_root) {
2050 			if (follow_up(&cur))
2051 				continue;
2052 			goto out_free;
2053 		}
2054 		if ((ncomponents & 15) == 0) {
2055 			struct dentry **new;
2056 			new = krealloc(components,
2057 					sizeof(*new) * (ncomponents + 16),
2058 					GFP_KERNEL);
2059 			if (!new)
2060 				goto out_free;
2061 			components = new;
2062 		}
2063 		components[ncomponents++] = cur.dentry;
2064 		cur.dentry = dget_parent(cur.dentry);
2065 	}
2066 	err = nfserr_resource;
2067 	p = xdr_reserve_space(xdr, 4);
2068 	if (!p)
2069 		goto out_free;
2070 	*p++ = cpu_to_be32(ncomponents);
2071 
2072 	while (ncomponents) {
2073 		struct dentry *dentry = components[ncomponents - 1];
2074 		unsigned int len;
2075 
2076 		spin_lock(&dentry->d_lock);
2077 		len = dentry->d_name.len;
2078 		p = xdr_reserve_space(xdr, len + 4);
2079 		if (!p) {
2080 			spin_unlock(&dentry->d_lock);
2081 			goto out_free;
2082 		}
2083 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
2084 		dprintk("/%pd", dentry);
2085 		spin_unlock(&dentry->d_lock);
2086 		dput(dentry);
2087 		ncomponents--;
2088 	}
2089 
2090 	err = 0;
2091 out_free:
2092 	dprintk(")\n");
2093 	while (ncomponents)
2094 		dput(components[--ncomponents]);
2095 	kfree(components);
2096 	path_put(&cur);
2097 	return err;
2098 }
2099 
2100 static __be32 nfsd4_encode_fsloc_fsroot(struct xdr_stream *xdr,
2101 			struct svc_rqst *rqstp, const struct path *path)
2102 {
2103 	struct svc_export *exp_ps;
2104 	__be32 res;
2105 
2106 	exp_ps = rqst_find_fsidzero_export(rqstp);
2107 	if (IS_ERR(exp_ps))
2108 		return nfserrno(PTR_ERR(exp_ps));
2109 	res = nfsd4_encode_path(xdr, &exp_ps->ex_path, path);
2110 	exp_put(exp_ps);
2111 	return res;
2112 }
2113 
2114 /*
2115  *  encode a fs_locations structure
2116  */
2117 static __be32 nfsd4_encode_fs_locations(struct xdr_stream *xdr,
2118 			struct svc_rqst *rqstp, struct svc_export *exp)
2119 {
2120 	__be32 status;
2121 	int i;
2122 	__be32 *p;
2123 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
2124 
2125 	status = nfsd4_encode_fsloc_fsroot(xdr, rqstp, &exp->ex_path);
2126 	if (status)
2127 		return status;
2128 	p = xdr_reserve_space(xdr, 4);
2129 	if (!p)
2130 		return nfserr_resource;
2131 	*p++ = cpu_to_be32(fslocs->locations_count);
2132 	for (i=0; i<fslocs->locations_count; i++) {
2133 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
2134 		if (status)
2135 			return status;
2136 	}
2137 	return 0;
2138 }
2139 
2140 static u32 nfs4_file_type(umode_t mode)
2141 {
2142 	switch (mode & S_IFMT) {
2143 	case S_IFIFO:	return NF4FIFO;
2144 	case S_IFCHR:	return NF4CHR;
2145 	case S_IFDIR:	return NF4DIR;
2146 	case S_IFBLK:	return NF4BLK;
2147 	case S_IFLNK:	return NF4LNK;
2148 	case S_IFREG:	return NF4REG;
2149 	case S_IFSOCK:	return NF4SOCK;
2150 	default:	return NF4BAD;
2151 	};
2152 }
2153 
2154 static inline __be32
2155 nfsd4_encode_aclname(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2156 		     struct nfs4_ace *ace)
2157 {
2158 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
2159 		return nfs4_acl_write_who(xdr, ace->whotype);
2160 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
2161 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
2162 	else
2163 		return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
2164 }
2165 
2166 static inline __be32
2167 nfsd4_encode_layout_type(struct xdr_stream *xdr, enum pnfs_layouttype layout_type)
2168 {
2169 	__be32 *p;
2170 
2171 	if (layout_type) {
2172 		p = xdr_reserve_space(xdr, 8);
2173 		if (!p)
2174 			return nfserr_resource;
2175 		*p++ = cpu_to_be32(1);
2176 		*p++ = cpu_to_be32(layout_type);
2177 	} else {
2178 		p = xdr_reserve_space(xdr, 4);
2179 		if (!p)
2180 			return nfserr_resource;
2181 		*p++ = cpu_to_be32(0);
2182 	}
2183 
2184 	return 0;
2185 }
2186 
2187 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
2188 			      FATTR4_WORD0_RDATTR_ERROR)
2189 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2190 #define WORD2_ABSENT_FS_ATTRS 0
2191 
2192 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2193 static inline __be32
2194 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2195 			    void *context, int len)
2196 {
2197 	__be32 *p;
2198 
2199 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2200 	if (!p)
2201 		return nfserr_resource;
2202 
2203 	/*
2204 	 * For now we use a 0 here to indicate the null translation; in
2205 	 * the future we may place a call to translation code here.
2206 	 */
2207 	*p++ = cpu_to_be32(0); /* lfs */
2208 	*p++ = cpu_to_be32(0); /* pi */
2209 	p = xdr_encode_opaque(p, context, len);
2210 	return 0;
2211 }
2212 #else
2213 static inline __be32
2214 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2215 			    void *context, int len)
2216 { return 0; }
2217 #endif
2218 
2219 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *bmval2, u32 *rdattr_err)
2220 {
2221 	/* As per referral draft:  */
2222 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2223 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2224 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2225 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2226 			*rdattr_err = NFSERR_MOVED;
2227 		else
2228 			return nfserr_moved;
2229 	}
2230 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2231 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2232 	*bmval2 &= WORD2_ABSENT_FS_ATTRS;
2233 	return 0;
2234 }
2235 
2236 
2237 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2238 {
2239 	struct path path = exp->ex_path;
2240 	int err;
2241 
2242 	path_get(&path);
2243 	while (follow_up(&path)) {
2244 		if (path.dentry != path.mnt->mnt_root)
2245 			break;
2246 	}
2247 	err = vfs_getattr(&path, stat);
2248 	path_put(&path);
2249 	return err;
2250 }
2251 
2252 static __be32
2253 nfsd4_encode_bitmap(struct xdr_stream *xdr, u32 bmval0, u32 bmval1, u32 bmval2)
2254 {
2255 	__be32 *p;
2256 
2257 	if (bmval2) {
2258 		p = xdr_reserve_space(xdr, 16);
2259 		if (!p)
2260 			goto out_resource;
2261 		*p++ = cpu_to_be32(3);
2262 		*p++ = cpu_to_be32(bmval0);
2263 		*p++ = cpu_to_be32(bmval1);
2264 		*p++ = cpu_to_be32(bmval2);
2265 	} else if (bmval1) {
2266 		p = xdr_reserve_space(xdr, 12);
2267 		if (!p)
2268 			goto out_resource;
2269 		*p++ = cpu_to_be32(2);
2270 		*p++ = cpu_to_be32(bmval0);
2271 		*p++ = cpu_to_be32(bmval1);
2272 	} else {
2273 		p = xdr_reserve_space(xdr, 8);
2274 		if (!p)
2275 			goto out_resource;
2276 		*p++ = cpu_to_be32(1);
2277 		*p++ = cpu_to_be32(bmval0);
2278 	}
2279 
2280 	return 0;
2281 out_resource:
2282 	return nfserr_resource;
2283 }
2284 
2285 /*
2286  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2287  * ourselves.
2288  */
2289 static __be32
2290 nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
2291 		struct svc_export *exp,
2292 		struct dentry *dentry, u32 *bmval,
2293 		struct svc_rqst *rqstp, int ignore_crossmnt)
2294 {
2295 	u32 bmval0 = bmval[0];
2296 	u32 bmval1 = bmval[1];
2297 	u32 bmval2 = bmval[2];
2298 	struct kstat stat;
2299 	struct svc_fh *tempfh = NULL;
2300 	struct kstatfs statfs;
2301 	__be32 *p;
2302 	int starting_len = xdr->buf->len;
2303 	int attrlen_offset;
2304 	__be32 attrlen;
2305 	u32 dummy;
2306 	u64 dummy64;
2307 	u32 rdattr_err = 0;
2308 	__be32 status;
2309 	int err;
2310 	struct nfs4_acl *acl = NULL;
2311 	void *context = NULL;
2312 	int contextlen;
2313 	bool contextsupport = false;
2314 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2315 	u32 minorversion = resp->cstate.minorversion;
2316 	struct path path = {
2317 		.mnt	= exp->ex_path.mnt,
2318 		.dentry	= dentry,
2319 	};
2320 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2321 
2322 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2323 	BUG_ON(bmval0 & ~nfsd_suppattrs0(minorversion));
2324 	BUG_ON(bmval1 & ~nfsd_suppattrs1(minorversion));
2325 	BUG_ON(bmval2 & ~nfsd_suppattrs2(minorversion));
2326 
2327 	if (exp->ex_fslocs.migrated) {
2328 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &bmval2, &rdattr_err);
2329 		if (status)
2330 			goto out;
2331 	}
2332 
2333 	err = vfs_getattr(&path, &stat);
2334 	if (err)
2335 		goto out_nfserr;
2336 	if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
2337 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
2338 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2339 		       FATTR4_WORD1_SPACE_TOTAL))) {
2340 		err = vfs_statfs(&path, &statfs);
2341 		if (err)
2342 			goto out_nfserr;
2343 	}
2344 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2345 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2346 		status = nfserr_jukebox;
2347 		if (!tempfh)
2348 			goto out;
2349 		fh_init(tempfh, NFS4_FHSIZE);
2350 		status = fh_compose(tempfh, exp, dentry, NULL);
2351 		if (status)
2352 			goto out;
2353 		fhp = tempfh;
2354 	}
2355 	if (bmval0 & FATTR4_WORD0_ACL) {
2356 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2357 		if (err == -EOPNOTSUPP)
2358 			bmval0 &= ~FATTR4_WORD0_ACL;
2359 		else if (err == -EINVAL) {
2360 			status = nfserr_attrnotsupp;
2361 			goto out;
2362 		} else if (err != 0)
2363 			goto out_nfserr;
2364 	}
2365 
2366 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2367 	if ((bmval2 & FATTR4_WORD2_SECURITY_LABEL) ||
2368 	     bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2369 		err = security_inode_getsecctx(d_inode(dentry),
2370 						&context, &contextlen);
2371 		contextsupport = (err == 0);
2372 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2373 			if (err == -EOPNOTSUPP)
2374 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2375 			else if (err)
2376 				goto out_nfserr;
2377 		}
2378 	}
2379 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2380 
2381 	status = nfsd4_encode_bitmap(xdr, bmval0, bmval1, bmval2);
2382 	if (status)
2383 		goto out;
2384 
2385 	attrlen_offset = xdr->buf->len;
2386 	p = xdr_reserve_space(xdr, 4);
2387 	if (!p)
2388 		goto out_resource;
2389 	p++;                /* to be backfilled later */
2390 
2391 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2392 		u32 word0 = nfsd_suppattrs0(minorversion);
2393 		u32 word1 = nfsd_suppattrs1(minorversion);
2394 		u32 word2 = nfsd_suppattrs2(minorversion);
2395 
2396 		if (!IS_POSIXACL(dentry->d_inode))
2397 			word0 &= ~FATTR4_WORD0_ACL;
2398 		if (!contextsupport)
2399 			word2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2400 		if (!word2) {
2401 			p = xdr_reserve_space(xdr, 12);
2402 			if (!p)
2403 				goto out_resource;
2404 			*p++ = cpu_to_be32(2);
2405 			*p++ = cpu_to_be32(word0);
2406 			*p++ = cpu_to_be32(word1);
2407 		} else {
2408 			p = xdr_reserve_space(xdr, 16);
2409 			if (!p)
2410 				goto out_resource;
2411 			*p++ = cpu_to_be32(3);
2412 			*p++ = cpu_to_be32(word0);
2413 			*p++ = cpu_to_be32(word1);
2414 			*p++ = cpu_to_be32(word2);
2415 		}
2416 	}
2417 	if (bmval0 & FATTR4_WORD0_TYPE) {
2418 		p = xdr_reserve_space(xdr, 4);
2419 		if (!p)
2420 			goto out_resource;
2421 		dummy = nfs4_file_type(stat.mode);
2422 		if (dummy == NF4BAD) {
2423 			status = nfserr_serverfault;
2424 			goto out;
2425 		}
2426 		*p++ = cpu_to_be32(dummy);
2427 	}
2428 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2429 		p = xdr_reserve_space(xdr, 4);
2430 		if (!p)
2431 			goto out_resource;
2432 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2433 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT);
2434 		else
2435 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT|
2436 						NFS4_FH_VOL_RENAME);
2437 	}
2438 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2439 		p = xdr_reserve_space(xdr, 8);
2440 		if (!p)
2441 			goto out_resource;
2442 		p = encode_change(p, &stat, d_inode(dentry));
2443 	}
2444 	if (bmval0 & FATTR4_WORD0_SIZE) {
2445 		p = xdr_reserve_space(xdr, 8);
2446 		if (!p)
2447 			goto out_resource;
2448 		p = xdr_encode_hyper(p, stat.size);
2449 	}
2450 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2451 		p = xdr_reserve_space(xdr, 4);
2452 		if (!p)
2453 			goto out_resource;
2454 		*p++ = cpu_to_be32(1);
2455 	}
2456 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2457 		p = xdr_reserve_space(xdr, 4);
2458 		if (!p)
2459 			goto out_resource;
2460 		*p++ = cpu_to_be32(1);
2461 	}
2462 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2463 		p = xdr_reserve_space(xdr, 4);
2464 		if (!p)
2465 			goto out_resource;
2466 		*p++ = cpu_to_be32(0);
2467 	}
2468 	if (bmval0 & FATTR4_WORD0_FSID) {
2469 		p = xdr_reserve_space(xdr, 16);
2470 		if (!p)
2471 			goto out_resource;
2472 		if (exp->ex_fslocs.migrated) {
2473 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
2474 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
2475 		} else switch(fsid_source(fhp)) {
2476 		case FSIDSOURCE_FSID:
2477 			p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
2478 			p = xdr_encode_hyper(p, (u64)0);
2479 			break;
2480 		case FSIDSOURCE_DEV:
2481 			*p++ = cpu_to_be32(0);
2482 			*p++ = cpu_to_be32(MAJOR(stat.dev));
2483 			*p++ = cpu_to_be32(0);
2484 			*p++ = cpu_to_be32(MINOR(stat.dev));
2485 			break;
2486 		case FSIDSOURCE_UUID:
2487 			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
2488 								EX_UUID_LEN);
2489 			break;
2490 		}
2491 	}
2492 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2493 		p = xdr_reserve_space(xdr, 4);
2494 		if (!p)
2495 			goto out_resource;
2496 		*p++ = cpu_to_be32(0);
2497 	}
2498 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2499 		p = xdr_reserve_space(xdr, 4);
2500 		if (!p)
2501 			goto out_resource;
2502 		*p++ = cpu_to_be32(nn->nfsd4_lease);
2503 	}
2504 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2505 		p = xdr_reserve_space(xdr, 4);
2506 		if (!p)
2507 			goto out_resource;
2508 		*p++ = cpu_to_be32(rdattr_err);
2509 	}
2510 	if (bmval0 & FATTR4_WORD0_ACL) {
2511 		struct nfs4_ace *ace;
2512 
2513 		if (acl == NULL) {
2514 			p = xdr_reserve_space(xdr, 4);
2515 			if (!p)
2516 				goto out_resource;
2517 
2518 			*p++ = cpu_to_be32(0);
2519 			goto out_acl;
2520 		}
2521 		p = xdr_reserve_space(xdr, 4);
2522 		if (!p)
2523 			goto out_resource;
2524 		*p++ = cpu_to_be32(acl->naces);
2525 
2526 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2527 			p = xdr_reserve_space(xdr, 4*3);
2528 			if (!p)
2529 				goto out_resource;
2530 			*p++ = cpu_to_be32(ace->type);
2531 			*p++ = cpu_to_be32(ace->flag);
2532 			*p++ = cpu_to_be32(ace->access_mask &
2533 							NFS4_ACE_MASK_ALL);
2534 			status = nfsd4_encode_aclname(xdr, rqstp, ace);
2535 			if (status)
2536 				goto out;
2537 		}
2538 	}
2539 out_acl:
2540 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2541 		p = xdr_reserve_space(xdr, 4);
2542 		if (!p)
2543 			goto out_resource;
2544 		*p++ = cpu_to_be32(IS_POSIXACL(dentry->d_inode) ?
2545 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2546 	}
2547 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2548 		p = xdr_reserve_space(xdr, 4);
2549 		if (!p)
2550 			goto out_resource;
2551 		*p++ = cpu_to_be32(1);
2552 	}
2553 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2554 		p = xdr_reserve_space(xdr, 4);
2555 		if (!p)
2556 			goto out_resource;
2557 		*p++ = cpu_to_be32(0);
2558 	}
2559 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2560 		p = xdr_reserve_space(xdr, 4);
2561 		if (!p)
2562 			goto out_resource;
2563 		*p++ = cpu_to_be32(1);
2564 	}
2565 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2566 		p = xdr_reserve_space(xdr, 4);
2567 		if (!p)
2568 			goto out_resource;
2569 		*p++ = cpu_to_be32(1);
2570 	}
2571 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2572 		p = xdr_reserve_space(xdr, fhp->fh_handle.fh_size + 4);
2573 		if (!p)
2574 			goto out_resource;
2575 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base,
2576 					fhp->fh_handle.fh_size);
2577 	}
2578 	if (bmval0 & FATTR4_WORD0_FILEID) {
2579 		p = xdr_reserve_space(xdr, 8);
2580 		if (!p)
2581 			goto out_resource;
2582 		p = xdr_encode_hyper(p, stat.ino);
2583 	}
2584 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2585 		p = xdr_reserve_space(xdr, 8);
2586 		if (!p)
2587 			goto out_resource;
2588 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2589 	}
2590 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2591 		p = xdr_reserve_space(xdr, 8);
2592 		if (!p)
2593 			goto out_resource;
2594 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2595 	}
2596 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2597 		p = xdr_reserve_space(xdr, 8);
2598 		if (!p)
2599 			goto out_resource;
2600 		p = xdr_encode_hyper(p, (u64) statfs.f_files);
2601 	}
2602 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2603 		status = nfsd4_encode_fs_locations(xdr, rqstp, exp);
2604 		if (status)
2605 			goto out;
2606 	}
2607 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2608 		p = xdr_reserve_space(xdr, 4);
2609 		if (!p)
2610 			goto out_resource;
2611 		*p++ = cpu_to_be32(1);
2612 	}
2613 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2614 		p = xdr_reserve_space(xdr, 8);
2615 		if (!p)
2616 			goto out_resource;
2617 		p = xdr_encode_hyper(p, exp->ex_path.mnt->mnt_sb->s_maxbytes);
2618 	}
2619 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2620 		p = xdr_reserve_space(xdr, 4);
2621 		if (!p)
2622 			goto out_resource;
2623 		*p++ = cpu_to_be32(255);
2624 	}
2625 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2626 		p = xdr_reserve_space(xdr, 4);
2627 		if (!p)
2628 			goto out_resource;
2629 		*p++ = cpu_to_be32(statfs.f_namelen);
2630 	}
2631 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2632 		p = xdr_reserve_space(xdr, 8);
2633 		if (!p)
2634 			goto out_resource;
2635 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2636 	}
2637 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2638 		p = xdr_reserve_space(xdr, 8);
2639 		if (!p)
2640 			goto out_resource;
2641 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2642 	}
2643 	if (bmval1 & FATTR4_WORD1_MODE) {
2644 		p = xdr_reserve_space(xdr, 4);
2645 		if (!p)
2646 			goto out_resource;
2647 		*p++ = cpu_to_be32(stat.mode & S_IALLUGO);
2648 	}
2649 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2650 		p = xdr_reserve_space(xdr, 4);
2651 		if (!p)
2652 			goto out_resource;
2653 		*p++ = cpu_to_be32(1);
2654 	}
2655 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2656 		p = xdr_reserve_space(xdr, 4);
2657 		if (!p)
2658 			goto out_resource;
2659 		*p++ = cpu_to_be32(stat.nlink);
2660 	}
2661 	if (bmval1 & FATTR4_WORD1_OWNER) {
2662 		status = nfsd4_encode_user(xdr, rqstp, stat.uid);
2663 		if (status)
2664 			goto out;
2665 	}
2666 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2667 		status = nfsd4_encode_group(xdr, rqstp, stat.gid);
2668 		if (status)
2669 			goto out;
2670 	}
2671 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2672 		p = xdr_reserve_space(xdr, 8);
2673 		if (!p)
2674 			goto out_resource;
2675 		*p++ = cpu_to_be32((u32) MAJOR(stat.rdev));
2676 		*p++ = cpu_to_be32((u32) MINOR(stat.rdev));
2677 	}
2678 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2679 		p = xdr_reserve_space(xdr, 8);
2680 		if (!p)
2681 			goto out_resource;
2682 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2683 		p = xdr_encode_hyper(p, dummy64);
2684 	}
2685 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2686 		p = xdr_reserve_space(xdr, 8);
2687 		if (!p)
2688 			goto out_resource;
2689 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2690 		p = xdr_encode_hyper(p, dummy64);
2691 	}
2692 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2693 		p = xdr_reserve_space(xdr, 8);
2694 		if (!p)
2695 			goto out_resource;
2696 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2697 		p = xdr_encode_hyper(p, dummy64);
2698 	}
2699 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2700 		p = xdr_reserve_space(xdr, 8);
2701 		if (!p)
2702 			goto out_resource;
2703 		dummy64 = (u64)stat.blocks << 9;
2704 		p = xdr_encode_hyper(p, dummy64);
2705 	}
2706 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2707 		p = xdr_reserve_space(xdr, 12);
2708 		if (!p)
2709 			goto out_resource;
2710 		p = xdr_encode_hyper(p, (s64)stat.atime.tv_sec);
2711 		*p++ = cpu_to_be32(stat.atime.tv_nsec);
2712 	}
2713 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2714 		p = xdr_reserve_space(xdr, 12);
2715 		if (!p)
2716 			goto out_resource;
2717 		*p++ = cpu_to_be32(0);
2718 		*p++ = cpu_to_be32(1);
2719 		*p++ = cpu_to_be32(0);
2720 	}
2721 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2722 		p = xdr_reserve_space(xdr, 12);
2723 		if (!p)
2724 			goto out_resource;
2725 		p = xdr_encode_hyper(p, (s64)stat.ctime.tv_sec);
2726 		*p++ = cpu_to_be32(stat.ctime.tv_nsec);
2727 	}
2728 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2729 		p = xdr_reserve_space(xdr, 12);
2730 		if (!p)
2731 			goto out_resource;
2732 		p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
2733 		*p++ = cpu_to_be32(stat.mtime.tv_nsec);
2734 	}
2735 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2736 		struct kstat parent_stat;
2737 		u64 ino = stat.ino;
2738 
2739 		p = xdr_reserve_space(xdr, 8);
2740 		if (!p)
2741                 	goto out_resource;
2742 		/*
2743 		 * Get parent's attributes if not ignoring crossmount
2744 		 * and this is the root of a cross-mounted filesystem.
2745 		 */
2746 		if (ignore_crossmnt == 0 &&
2747 		    dentry == exp->ex_path.mnt->mnt_root) {
2748 			err = get_parent_attributes(exp, &parent_stat);
2749 			if (err)
2750 				goto out_nfserr;
2751 			ino = parent_stat.ino;
2752 		}
2753 		p = xdr_encode_hyper(p, ino);
2754 	}
2755 #ifdef CONFIG_NFSD_PNFS
2756 	if (bmval1 & FATTR4_WORD1_FS_LAYOUT_TYPES) {
2757 		status = nfsd4_encode_layout_type(xdr, exp->ex_layout_type);
2758 		if (status)
2759 			goto out;
2760 	}
2761 
2762 	if (bmval2 & FATTR4_WORD2_LAYOUT_TYPES) {
2763 		status = nfsd4_encode_layout_type(xdr, exp->ex_layout_type);
2764 		if (status)
2765 			goto out;
2766 	}
2767 
2768 	if (bmval2 & FATTR4_WORD2_LAYOUT_BLKSIZE) {
2769 		p = xdr_reserve_space(xdr, 4);
2770 		if (!p)
2771 			goto out_resource;
2772 		*p++ = cpu_to_be32(stat.blksize);
2773 	}
2774 #endif /* CONFIG_NFSD_PNFS */
2775 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2776 		status = nfsd4_encode_bitmap(xdr, NFSD_SUPPATTR_EXCLCREAT_WORD0,
2777 						  NFSD_SUPPATTR_EXCLCREAT_WORD1,
2778 						  NFSD_SUPPATTR_EXCLCREAT_WORD2);
2779 		if (status)
2780 			goto out;
2781 	}
2782 
2783 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2784 		status = nfsd4_encode_security_label(xdr, rqstp, context,
2785 								contextlen);
2786 		if (status)
2787 			goto out;
2788 	}
2789 
2790 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
2791 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
2792 	status = nfs_ok;
2793 
2794 out:
2795 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2796 	if (context)
2797 		security_release_secctx(context, contextlen);
2798 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2799 	kfree(acl);
2800 	if (tempfh) {
2801 		fh_put(tempfh);
2802 		kfree(tempfh);
2803 	}
2804 	if (status)
2805 		xdr_truncate_encode(xdr, starting_len);
2806 	return status;
2807 out_nfserr:
2808 	status = nfserrno(err);
2809 	goto out;
2810 out_resource:
2811 	status = nfserr_resource;
2812 	goto out;
2813 }
2814 
2815 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
2816 				struct xdr_buf *buf, __be32 *p, int bytes)
2817 {
2818 	xdr->scratch.iov_len = 0;
2819 	memset(buf, 0, sizeof(struct xdr_buf));
2820 	buf->head[0].iov_base = p;
2821 	buf->head[0].iov_len = 0;
2822 	buf->len = 0;
2823 	xdr->buf = buf;
2824 	xdr->iov = buf->head;
2825 	xdr->p = p;
2826 	xdr->end = (void *)p + bytes;
2827 	buf->buflen = bytes;
2828 }
2829 
2830 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
2831 			struct svc_fh *fhp, struct svc_export *exp,
2832 			struct dentry *dentry, u32 *bmval,
2833 			struct svc_rqst *rqstp, int ignore_crossmnt)
2834 {
2835 	struct xdr_buf dummy;
2836 	struct xdr_stream xdr;
2837 	__be32 ret;
2838 
2839 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
2840 	ret = nfsd4_encode_fattr(&xdr, fhp, exp, dentry, bmval, rqstp,
2841 							ignore_crossmnt);
2842 	*p = xdr.p;
2843 	return ret;
2844 }
2845 
2846 static inline int attributes_need_mount(u32 *bmval)
2847 {
2848 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2849 		return 1;
2850 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2851 		return 1;
2852 	return 0;
2853 }
2854 
2855 static __be32
2856 nfsd4_encode_dirent_fattr(struct xdr_stream *xdr, struct nfsd4_readdir *cd,
2857 			const char *name, int namlen)
2858 {
2859 	struct svc_export *exp = cd->rd_fhp->fh_export;
2860 	struct dentry *dentry;
2861 	__be32 nfserr;
2862 	int ignore_crossmnt = 0;
2863 
2864 	dentry = lookup_one_len_unlocked(name, cd->rd_fhp->fh_dentry, namlen);
2865 	if (IS_ERR(dentry))
2866 		return nfserrno(PTR_ERR(dentry));
2867 	if (d_really_is_negative(dentry)) {
2868 		/*
2869 		 * we're not holding the i_mutex here, so there's
2870 		 * a window where this directory entry could have gone
2871 		 * away.
2872 		 */
2873 		dput(dentry);
2874 		return nfserr_noent;
2875 	}
2876 
2877 	exp_get(exp);
2878 	/*
2879 	 * In the case of a mountpoint, the client may be asking for
2880 	 * attributes that are only properties of the underlying filesystem
2881 	 * as opposed to the cross-mounted file system. In such a case,
2882 	 * we will not follow the cross mount and will fill the attribtutes
2883 	 * directly from the mountpoint dentry.
2884 	 */
2885 	if (nfsd_mountpoint(dentry, exp)) {
2886 		int err;
2887 
2888 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
2889 				&& !attributes_need_mount(cd->rd_bmval)) {
2890 			ignore_crossmnt = 1;
2891 			goto out_encode;
2892 		}
2893 		/*
2894 		 * Why the heck aren't we just using nfsd_lookup??
2895 		 * Different "."/".." handling?  Something else?
2896 		 * At least, add a comment here to explain....
2897 		 */
2898 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
2899 		if (err) {
2900 			nfserr = nfserrno(err);
2901 			goto out_put;
2902 		}
2903 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
2904 		if (nfserr)
2905 			goto out_put;
2906 
2907 	}
2908 out_encode:
2909 	nfserr = nfsd4_encode_fattr(xdr, NULL, exp, dentry, cd->rd_bmval,
2910 					cd->rd_rqstp, ignore_crossmnt);
2911 out_put:
2912 	dput(dentry);
2913 	exp_put(exp);
2914 	return nfserr;
2915 }
2916 
2917 static __be32 *
2918 nfsd4_encode_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
2919 {
2920 	__be32 *p;
2921 
2922 	p = xdr_reserve_space(xdr, 20);
2923 	if (!p)
2924 		return NULL;
2925 	*p++ = htonl(2);
2926 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
2927 	*p++ = htonl(0);			 /* bmval1 */
2928 
2929 	*p++ = htonl(4);     /* attribute length */
2930 	*p++ = nfserr;       /* no htonl */
2931 	return p;
2932 }
2933 
2934 static int
2935 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
2936 		    loff_t offset, u64 ino, unsigned int d_type)
2937 {
2938 	struct readdir_cd *ccd = ccdv;
2939 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
2940 	struct xdr_stream *xdr = cd->xdr;
2941 	int start_offset = xdr->buf->len;
2942 	int cookie_offset;
2943 	u32 name_and_cookie;
2944 	int entry_bytes;
2945 	__be32 nfserr = nfserr_toosmall;
2946 	__be64 wire_offset;
2947 	__be32 *p;
2948 
2949 	/* In nfsv4, "." and ".." never make it onto the wire.. */
2950 	if (name && isdotent(name, namlen)) {
2951 		cd->common.err = nfs_ok;
2952 		return 0;
2953 	}
2954 
2955 	if (cd->cookie_offset) {
2956 		wire_offset = cpu_to_be64(offset);
2957 		write_bytes_to_xdr_buf(xdr->buf, cd->cookie_offset,
2958 							&wire_offset, 8);
2959 	}
2960 
2961 	p = xdr_reserve_space(xdr, 4);
2962 	if (!p)
2963 		goto fail;
2964 	*p++ = xdr_one;                             /* mark entry present */
2965 	cookie_offset = xdr->buf->len;
2966 	p = xdr_reserve_space(xdr, 3*4 + namlen);
2967 	if (!p)
2968 		goto fail;
2969 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
2970 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
2971 
2972 	nfserr = nfsd4_encode_dirent_fattr(xdr, cd, name, namlen);
2973 	switch (nfserr) {
2974 	case nfs_ok:
2975 		break;
2976 	case nfserr_resource:
2977 		nfserr = nfserr_toosmall;
2978 		goto fail;
2979 	case nfserr_noent:
2980 		xdr_truncate_encode(xdr, start_offset);
2981 		goto skip_entry;
2982 	default:
2983 		/*
2984 		 * If the client requested the RDATTR_ERROR attribute,
2985 		 * we stuff the error code into this attribute
2986 		 * and continue.  If this attribute was not requested,
2987 		 * then in accordance with the spec, we fail the
2988 		 * entire READDIR operation(!)
2989 		 */
2990 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
2991 			goto fail;
2992 		p = nfsd4_encode_rdattr_error(xdr, nfserr);
2993 		if (p == NULL) {
2994 			nfserr = nfserr_toosmall;
2995 			goto fail;
2996 		}
2997 	}
2998 	nfserr = nfserr_toosmall;
2999 	entry_bytes = xdr->buf->len - start_offset;
3000 	if (entry_bytes > cd->rd_maxcount)
3001 		goto fail;
3002 	cd->rd_maxcount -= entry_bytes;
3003 	/*
3004 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so
3005 	 * let's always let through the first entry, at least:
3006 	 */
3007 	if (!cd->rd_dircount)
3008 		goto fail;
3009 	name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8;
3010 	if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
3011 		goto fail;
3012 	cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
3013 
3014 	cd->cookie_offset = cookie_offset;
3015 skip_entry:
3016 	cd->common.err = nfs_ok;
3017 	return 0;
3018 fail:
3019 	xdr_truncate_encode(xdr, start_offset);
3020 	cd->common.err = nfserr;
3021 	return -EINVAL;
3022 }
3023 
3024 static __be32
3025 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
3026 {
3027 	__be32 *p;
3028 
3029 	p = xdr_reserve_space(xdr, sizeof(stateid_t));
3030 	if (!p)
3031 		return nfserr_resource;
3032 	*p++ = cpu_to_be32(sid->si_generation);
3033 	p = xdr_encode_opaque_fixed(p, &sid->si_opaque,
3034 					sizeof(stateid_opaque_t));
3035 	return 0;
3036 }
3037 
3038 static __be32
3039 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
3040 {
3041 	struct xdr_stream *xdr = &resp->xdr;
3042 	__be32 *p;
3043 
3044 	if (!nfserr) {
3045 		p = xdr_reserve_space(xdr, 8);
3046 		if (!p)
3047 			return nfserr_resource;
3048 		*p++ = cpu_to_be32(access->ac_supported);
3049 		*p++ = cpu_to_be32(access->ac_resp_access);
3050 	}
3051 	return nfserr;
3052 }
3053 
3054 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
3055 {
3056 	struct xdr_stream *xdr = &resp->xdr;
3057 	__be32 *p;
3058 
3059 	if (!nfserr) {
3060 		p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 8);
3061 		if (!p)
3062 			return nfserr_resource;
3063 		p = xdr_encode_opaque_fixed(p, bcts->sessionid.data,
3064 						NFS4_MAX_SESSIONID_LEN);
3065 		*p++ = cpu_to_be32(bcts->dir);
3066 		/* Upshifting from TCP to RDMA is not supported */
3067 		*p++ = cpu_to_be32(0);
3068 	}
3069 	return nfserr;
3070 }
3071 
3072 static __be32
3073 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
3074 {
3075 	struct xdr_stream *xdr = &resp->xdr;
3076 
3077 	if (!nfserr)
3078 		nfserr = nfsd4_encode_stateid(xdr, &close->cl_stateid);
3079 
3080 	return nfserr;
3081 }
3082 
3083 
3084 static __be32
3085 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
3086 {
3087 	struct xdr_stream *xdr = &resp->xdr;
3088 	__be32 *p;
3089 
3090 	if (!nfserr) {
3091 		p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3092 		if (!p)
3093 			return nfserr_resource;
3094 		p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
3095 						NFS4_VERIFIER_SIZE);
3096 	}
3097 	return nfserr;
3098 }
3099 
3100 static __be32
3101 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
3102 {
3103 	struct xdr_stream *xdr = &resp->xdr;
3104 	__be32 *p;
3105 
3106 	if (!nfserr) {
3107 		p = xdr_reserve_space(xdr, 20);
3108 		if (!p)
3109 			return nfserr_resource;
3110 		encode_cinfo(p, &create->cr_cinfo);
3111 		nfserr = nfsd4_encode_bitmap(xdr, create->cr_bmval[0],
3112 				create->cr_bmval[1], create->cr_bmval[2]);
3113 	}
3114 	return nfserr;
3115 }
3116 
3117 static __be32
3118 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
3119 {
3120 	struct svc_fh *fhp = getattr->ga_fhp;
3121 	struct xdr_stream *xdr = &resp->xdr;
3122 
3123 	if (nfserr)
3124 		return nfserr;
3125 
3126 	nfserr = nfsd4_encode_fattr(xdr, fhp, fhp->fh_export, fhp->fh_dentry,
3127 				    getattr->ga_bmval,
3128 				    resp->rqstp, 0);
3129 	return nfserr;
3130 }
3131 
3132 static __be32
3133 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
3134 {
3135 	struct xdr_stream *xdr = &resp->xdr;
3136 	struct svc_fh *fhp = *fhpp;
3137 	unsigned int len;
3138 	__be32 *p;
3139 
3140 	if (!nfserr) {
3141 		len = fhp->fh_handle.fh_size;
3142 		p = xdr_reserve_space(xdr, len + 4);
3143 		if (!p)
3144 			return nfserr_resource;
3145 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base, len);
3146 	}
3147 	return nfserr;
3148 }
3149 
3150 /*
3151 * Including all fields other than the name, a LOCK4denied structure requires
3152 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
3153 */
3154 static __be32
3155 nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld)
3156 {
3157 	struct xdr_netobj *conf = &ld->ld_owner;
3158 	__be32 *p;
3159 
3160 again:
3161 	p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len));
3162 	if (!p) {
3163 		/*
3164 		 * Don't fail to return the result just because we can't
3165 		 * return the conflicting open:
3166 		 */
3167 		if (conf->len) {
3168 			kfree(conf->data);
3169 			conf->len = 0;
3170 			conf->data = NULL;
3171 			goto again;
3172 		}
3173 		return nfserr_resource;
3174 	}
3175 	p = xdr_encode_hyper(p, ld->ld_start);
3176 	p = xdr_encode_hyper(p, ld->ld_length);
3177 	*p++ = cpu_to_be32(ld->ld_type);
3178 	if (conf->len) {
3179 		p = xdr_encode_opaque_fixed(p, &ld->ld_clientid, 8);
3180 		p = xdr_encode_opaque(p, conf->data, conf->len);
3181 		kfree(conf->data);
3182 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
3183 		p = xdr_encode_hyper(p, (u64)0); /* clientid */
3184 		*p++ = cpu_to_be32(0); /* length of owner name */
3185 	}
3186 	return nfserr_denied;
3187 }
3188 
3189 static __be32
3190 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
3191 {
3192 	struct xdr_stream *xdr = &resp->xdr;
3193 
3194 	if (!nfserr)
3195 		nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid);
3196 	else if (nfserr == nfserr_denied)
3197 		nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied);
3198 
3199 	return nfserr;
3200 }
3201 
3202 static __be32
3203 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
3204 {
3205 	struct xdr_stream *xdr = &resp->xdr;
3206 
3207 	if (nfserr == nfserr_denied)
3208 		nfsd4_encode_lock_denied(xdr, &lockt->lt_denied);
3209 	return nfserr;
3210 }
3211 
3212 static __be32
3213 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
3214 {
3215 	struct xdr_stream *xdr = &resp->xdr;
3216 
3217 	if (!nfserr)
3218 		nfserr = nfsd4_encode_stateid(xdr, &locku->lu_stateid);
3219 
3220 	return nfserr;
3221 }
3222 
3223 
3224 static __be32
3225 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
3226 {
3227 	struct xdr_stream *xdr = &resp->xdr;
3228 	__be32 *p;
3229 
3230 	if (!nfserr) {
3231 		p = xdr_reserve_space(xdr, 20);
3232 		if (!p)
3233 			return nfserr_resource;
3234 		p = encode_cinfo(p, &link->li_cinfo);
3235 	}
3236 	return nfserr;
3237 }
3238 
3239 
3240 static __be32
3241 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
3242 {
3243 	struct xdr_stream *xdr = &resp->xdr;
3244 	__be32 *p;
3245 
3246 	if (nfserr)
3247 		goto out;
3248 
3249 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
3250 	if (nfserr)
3251 		goto out;
3252 	p = xdr_reserve_space(xdr, 24);
3253 	if (!p)
3254 		return nfserr_resource;
3255 	p = encode_cinfo(p, &open->op_cinfo);
3256 	*p++ = cpu_to_be32(open->op_rflags);
3257 
3258 	nfserr = nfsd4_encode_bitmap(xdr, open->op_bmval[0], open->op_bmval[1],
3259 					open->op_bmval[2]);
3260 	if (nfserr)
3261 		goto out;
3262 
3263 	p = xdr_reserve_space(xdr, 4);
3264 	if (!p)
3265 		return nfserr_resource;
3266 
3267 	*p++ = cpu_to_be32(open->op_delegate_type);
3268 	switch (open->op_delegate_type) {
3269 	case NFS4_OPEN_DELEGATE_NONE:
3270 		break;
3271 	case NFS4_OPEN_DELEGATE_READ:
3272 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3273 		if (nfserr)
3274 			return nfserr;
3275 		p = xdr_reserve_space(xdr, 20);
3276 		if (!p)
3277 			return nfserr_resource;
3278 		*p++ = cpu_to_be32(open->op_recall);
3279 
3280 		/*
3281 		 * TODO: ACE's in delegations
3282 		 */
3283 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3284 		*p++ = cpu_to_be32(0);
3285 		*p++ = cpu_to_be32(0);
3286 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3287 		break;
3288 	case NFS4_OPEN_DELEGATE_WRITE:
3289 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3290 		if (nfserr)
3291 			return nfserr;
3292 		p = xdr_reserve_space(xdr, 32);
3293 		if (!p)
3294 			return nfserr_resource;
3295 		*p++ = cpu_to_be32(0);
3296 
3297 		/*
3298 		 * TODO: space_limit's in delegations
3299 		 */
3300 		*p++ = cpu_to_be32(NFS4_LIMIT_SIZE);
3301 		*p++ = cpu_to_be32(~(u32)0);
3302 		*p++ = cpu_to_be32(~(u32)0);
3303 
3304 		/*
3305 		 * TODO: ACE's in delegations
3306 		 */
3307 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3308 		*p++ = cpu_to_be32(0);
3309 		*p++ = cpu_to_be32(0);
3310 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3311 		break;
3312 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
3313 		switch (open->op_why_no_deleg) {
3314 		case WND4_CONTENTION:
3315 		case WND4_RESOURCE:
3316 			p = xdr_reserve_space(xdr, 8);
3317 			if (!p)
3318 				return nfserr_resource;
3319 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3320 			/* deleg signaling not supported yet: */
3321 			*p++ = cpu_to_be32(0);
3322 			break;
3323 		default:
3324 			p = xdr_reserve_space(xdr, 4);
3325 			if (!p)
3326 				return nfserr_resource;
3327 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3328 		}
3329 		break;
3330 	default:
3331 		BUG();
3332 	}
3333 	/* XXX save filehandle here */
3334 out:
3335 	return nfserr;
3336 }
3337 
3338 static __be32
3339 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
3340 {
3341 	struct xdr_stream *xdr = &resp->xdr;
3342 
3343 	if (!nfserr)
3344 		nfserr = nfsd4_encode_stateid(xdr, &oc->oc_resp_stateid);
3345 
3346 	return nfserr;
3347 }
3348 
3349 static __be32
3350 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
3351 {
3352 	struct xdr_stream *xdr = &resp->xdr;
3353 
3354 	if (!nfserr)
3355 		nfserr = nfsd4_encode_stateid(xdr, &od->od_stateid);
3356 
3357 	return nfserr;
3358 }
3359 
3360 static __be32 nfsd4_encode_splice_read(
3361 				struct nfsd4_compoundres *resp,
3362 				struct nfsd4_read *read,
3363 				struct file *file, unsigned long maxcount)
3364 {
3365 	struct xdr_stream *xdr = &resp->xdr;
3366 	struct xdr_buf *buf = xdr->buf;
3367 	u32 eof;
3368 	long len;
3369 	int space_left;
3370 	__be32 nfserr;
3371 	__be32 *p = xdr->p - 2;
3372 
3373 	/* Make sure there will be room for padding if needed */
3374 	if (xdr->end - xdr->p < 1)
3375 		return nfserr_resource;
3376 
3377 	len = maxcount;
3378 	nfserr = nfsd_splice_read(read->rd_rqstp, file,
3379 				  read->rd_offset, &maxcount);
3380 	if (nfserr) {
3381 		/*
3382 		 * nfsd_splice_actor may have already messed with the
3383 		 * page length; reset it so as not to confuse
3384 		 * xdr_truncate_encode:
3385 		 */
3386 		buf->page_len = 0;
3387 		return nfserr;
3388 	}
3389 
3390 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3391 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3392 
3393 	*(p++) = htonl(eof);
3394 	*(p++) = htonl(maxcount);
3395 
3396 	buf->page_len = maxcount;
3397 	buf->len += maxcount;
3398 	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
3399 							/ PAGE_SIZE;
3400 
3401 	/* Use rest of head for padding and remaining ops: */
3402 	buf->tail[0].iov_base = xdr->p;
3403 	buf->tail[0].iov_len = 0;
3404 	xdr->iov = buf->tail;
3405 	if (maxcount&3) {
3406 		int pad = 4 - (maxcount&3);
3407 
3408 		*(xdr->p++) = 0;
3409 
3410 		buf->tail[0].iov_base += maxcount&3;
3411 		buf->tail[0].iov_len = pad;
3412 		buf->len += pad;
3413 	}
3414 
3415 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
3416 				buf->buflen - buf->len);
3417 	buf->buflen = buf->len + space_left;
3418 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
3419 
3420 	return 0;
3421 }
3422 
3423 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
3424 				 struct nfsd4_read *read,
3425 				 struct file *file, unsigned long maxcount)
3426 {
3427 	struct xdr_stream *xdr = &resp->xdr;
3428 	u32 eof;
3429 	int v;
3430 	int starting_len = xdr->buf->len - 8;
3431 	long len;
3432 	int thislen;
3433 	__be32 nfserr;
3434 	__be32 tmp;
3435 	__be32 *p;
3436 	u32 zzz = 0;
3437 	int pad;
3438 
3439 	len = maxcount;
3440 	v = 0;
3441 
3442 	thislen = min_t(long, len, ((void *)xdr->end - (void *)xdr->p));
3443 	p = xdr_reserve_space(xdr, (thislen+3)&~3);
3444 	WARN_ON_ONCE(!p);
3445 	resp->rqstp->rq_vec[v].iov_base = p;
3446 	resp->rqstp->rq_vec[v].iov_len = thislen;
3447 	v++;
3448 	len -= thislen;
3449 
3450 	while (len) {
3451 		thislen = min_t(long, len, PAGE_SIZE);
3452 		p = xdr_reserve_space(xdr, (thislen+3)&~3);
3453 		WARN_ON_ONCE(!p);
3454 		resp->rqstp->rq_vec[v].iov_base = p;
3455 		resp->rqstp->rq_vec[v].iov_len = thislen;
3456 		v++;
3457 		len -= thislen;
3458 	}
3459 	read->rd_vlen = v;
3460 
3461 	len = maxcount;
3462 	nfserr = nfsd_readv(file, read->rd_offset, resp->rqstp->rq_vec,
3463 			read->rd_vlen, &maxcount);
3464 	if (nfserr)
3465 		return nfserr;
3466 	xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3));
3467 
3468 	eof = nfsd_eof_on_read(len, maxcount, read->rd_offset,
3469 				d_inode(read->rd_fhp->fh_dentry)->i_size);
3470 
3471 	tmp = htonl(eof);
3472 	write_bytes_to_xdr_buf(xdr->buf, starting_len    , &tmp, 4);
3473 	tmp = htonl(maxcount);
3474 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
3475 
3476 	pad = (maxcount&3) ? 4 - (maxcount&3) : 0;
3477 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 8 + maxcount,
3478 								&zzz, pad);
3479 	return 0;
3480 
3481 }
3482 
3483 static __be32
3484 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
3485 		  struct nfsd4_read *read)
3486 {
3487 	unsigned long maxcount;
3488 	struct xdr_stream *xdr = &resp->xdr;
3489 	struct file *file = read->rd_filp;
3490 	int starting_len = xdr->buf->len;
3491 	struct raparms *ra = NULL;
3492 	__be32 *p;
3493 
3494 	if (nfserr)
3495 		goto out;
3496 
3497 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
3498 	if (!p) {
3499 		WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
3500 		nfserr = nfserr_resource;
3501 		goto out;
3502 	}
3503 	if (resp->xdr.buf->page_len &&
3504 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
3505 		WARN_ON_ONCE(1);
3506 		nfserr = nfserr_resource;
3507 		goto out;
3508 	}
3509 	xdr_commit_encode(xdr);
3510 
3511 	maxcount = svc_max_payload(resp->rqstp);
3512 	maxcount = min_t(unsigned long, maxcount,
3513 			 (xdr->buf->buflen - xdr->buf->len));
3514 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
3515 
3516 	if (read->rd_tmp_file)
3517 		ra = nfsd_init_raparms(file);
3518 
3519 	if (file->f_op->splice_read &&
3520 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
3521 		nfserr = nfsd4_encode_splice_read(resp, read, file, maxcount);
3522 	else
3523 		nfserr = nfsd4_encode_readv(resp, read, file, maxcount);
3524 
3525 	if (ra)
3526 		nfsd_put_raparams(file, ra);
3527 
3528 	if (nfserr)
3529 		xdr_truncate_encode(xdr, starting_len);
3530 
3531 out:
3532 	if (file)
3533 		fput(file);
3534 	return nfserr;
3535 }
3536 
3537 static __be32
3538 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3539 {
3540 	int maxcount;
3541 	__be32 wire_count;
3542 	int zero = 0;
3543 	struct xdr_stream *xdr = &resp->xdr;
3544 	int length_offset = xdr->buf->len;
3545 	__be32 *p;
3546 
3547 	if (nfserr)
3548 		return nfserr;
3549 
3550 	p = xdr_reserve_space(xdr, 4);
3551 	if (!p)
3552 		return nfserr_resource;
3553 	maxcount = PAGE_SIZE;
3554 
3555 	p = xdr_reserve_space(xdr, maxcount);
3556 	if (!p)
3557 		return nfserr_resource;
3558 	/*
3559 	 * XXX: By default, the ->readlink() VFS op will truncate symlinks
3560 	 * if they would overflow the buffer.  Is this kosher in NFSv4?  If
3561 	 * not, one easy fix is: if ->readlink() precisely fills the buffer,
3562 	 * assume that truncation occurred, and return NFS4ERR_RESOURCE.
3563 	 */
3564 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
3565 						(char *)p, &maxcount);
3566 	if (nfserr == nfserr_isdir)
3567 		nfserr = nfserr_inval;
3568 	if (nfserr) {
3569 		xdr_truncate_encode(xdr, length_offset);
3570 		return nfserr;
3571 	}
3572 
3573 	wire_count = htonl(maxcount);
3574 	write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
3575 	xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
3576 	if (maxcount & 3)
3577 		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
3578 						&zero, 4 - (maxcount&3));
3579 	return 0;
3580 }
3581 
3582 static __be32
3583 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3584 {
3585 	int maxcount;
3586 	int bytes_left;
3587 	loff_t offset;
3588 	__be64 wire_offset;
3589 	struct xdr_stream *xdr = &resp->xdr;
3590 	int starting_len = xdr->buf->len;
3591 	__be32 *p;
3592 
3593 	if (nfserr)
3594 		return nfserr;
3595 
3596 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3597 	if (!p)
3598 		return nfserr_resource;
3599 
3600 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3601 	*p++ = cpu_to_be32(0);
3602 	*p++ = cpu_to_be32(0);
3603 	resp->xdr.buf->head[0].iov_len = ((char *)resp->xdr.p)
3604 				- (char *)resp->xdr.buf->head[0].iov_base;
3605 
3606 	/*
3607 	 * Number of bytes left for directory entries allowing for the
3608 	 * final 8 bytes of the readdir and a following failed op:
3609 	 */
3610 	bytes_left = xdr->buf->buflen - xdr->buf->len
3611 			- COMPOUND_ERR_SLACK_SPACE - 8;
3612 	if (bytes_left < 0) {
3613 		nfserr = nfserr_resource;
3614 		goto err_no_verf;
3615 	}
3616 	maxcount = min_t(u32, readdir->rd_maxcount, INT_MAX);
3617 	/*
3618 	 * Note the rfc defines rd_maxcount as the size of the
3619 	 * READDIR4resok structure, which includes the verifier above
3620 	 * and the 8 bytes encoded at the end of this function:
3621 	 */
3622 	if (maxcount < 16) {
3623 		nfserr = nfserr_toosmall;
3624 		goto err_no_verf;
3625 	}
3626 	maxcount = min_t(int, maxcount-16, bytes_left);
3627 
3628 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
3629 	if (!readdir->rd_dircount)
3630 		readdir->rd_dircount = INT_MAX;
3631 
3632 	readdir->xdr = xdr;
3633 	readdir->rd_maxcount = maxcount;
3634 	readdir->common.err = 0;
3635 	readdir->cookie_offset = 0;
3636 
3637 	offset = readdir->rd_cookie;
3638 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3639 			      &offset,
3640 			      &readdir->common, nfsd4_encode_dirent);
3641 	if (nfserr == nfs_ok &&
3642 	    readdir->common.err == nfserr_toosmall &&
3643 	    xdr->buf->len == starting_len + 8) {
3644 		/* nothing encoded; which limit did we hit?: */
3645 		if (maxcount - 16 < bytes_left)
3646 			/* It was the fault of rd_maxcount: */
3647 			nfserr = nfserr_toosmall;
3648 		else
3649 			/* We ran out of buffer space: */
3650 			nfserr = nfserr_resource;
3651 	}
3652 	if (nfserr)
3653 		goto err_no_verf;
3654 
3655 	if (readdir->cookie_offset) {
3656 		wire_offset = cpu_to_be64(offset);
3657 		write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset,
3658 							&wire_offset, 8);
3659 	}
3660 
3661 	p = xdr_reserve_space(xdr, 8);
3662 	if (!p) {
3663 		WARN_ON_ONCE(1);
3664 		goto err_no_verf;
3665 	}
3666 	*p++ = 0;	/* no more entries */
3667 	*p++ = htonl(readdir->common.err == nfserr_eof);
3668 
3669 	return 0;
3670 err_no_verf:
3671 	xdr_truncate_encode(xdr, starting_len);
3672 	return nfserr;
3673 }
3674 
3675 static __be32
3676 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3677 {
3678 	struct xdr_stream *xdr = &resp->xdr;
3679 	__be32 *p;
3680 
3681 	if (!nfserr) {
3682 		p = xdr_reserve_space(xdr, 20);
3683 		if (!p)
3684 			return nfserr_resource;
3685 		p = encode_cinfo(p, &remove->rm_cinfo);
3686 	}
3687 	return nfserr;
3688 }
3689 
3690 static __be32
3691 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3692 {
3693 	struct xdr_stream *xdr = &resp->xdr;
3694 	__be32 *p;
3695 
3696 	if (!nfserr) {
3697 		p = xdr_reserve_space(xdr, 40);
3698 		if (!p)
3699 			return nfserr_resource;
3700 		p = encode_cinfo(p, &rename->rn_sinfo);
3701 		p = encode_cinfo(p, &rename->rn_tinfo);
3702 	}
3703 	return nfserr;
3704 }
3705 
3706 static __be32
3707 nfsd4_do_encode_secinfo(struct xdr_stream *xdr,
3708 			 __be32 nfserr, struct svc_export *exp)
3709 {
3710 	u32 i, nflavs, supported;
3711 	struct exp_flavor_info *flavs;
3712 	struct exp_flavor_info def_flavs[2];
3713 	__be32 *p, *flavorsp;
3714 	static bool report = true;
3715 
3716 	if (nfserr)
3717 		goto out;
3718 	nfserr = nfserr_resource;
3719 	if (exp->ex_nflavors) {
3720 		flavs = exp->ex_flavors;
3721 		nflavs = exp->ex_nflavors;
3722 	} else { /* Handling of some defaults in absence of real secinfo: */
3723 		flavs = def_flavs;
3724 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3725 			nflavs = 2;
3726 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3727 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3728 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3729 			nflavs = 1;
3730 			flavs[0].pseudoflavor
3731 					= svcauth_gss_flavor(exp->ex_client);
3732 		} else {
3733 			nflavs = 1;
3734 			flavs[0].pseudoflavor
3735 					= exp->ex_client->flavour->flavour;
3736 		}
3737 	}
3738 
3739 	supported = 0;
3740 	p = xdr_reserve_space(xdr, 4);
3741 	if (!p)
3742 		goto out;
3743 	flavorsp = p++;		/* to be backfilled later */
3744 
3745 	for (i = 0; i < nflavs; i++) {
3746 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
3747 		struct rpcsec_gss_info info;
3748 
3749 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
3750 			supported++;
3751 			p = xdr_reserve_space(xdr, 4 + 4 +
3752 					      XDR_LEN(info.oid.len) + 4 + 4);
3753 			if (!p)
3754 				goto out;
3755 			*p++ = cpu_to_be32(RPC_AUTH_GSS);
3756 			p = xdr_encode_opaque(p,  info.oid.data, info.oid.len);
3757 			*p++ = cpu_to_be32(info.qop);
3758 			*p++ = cpu_to_be32(info.service);
3759 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
3760 			supported++;
3761 			p = xdr_reserve_space(xdr, 4);
3762 			if (!p)
3763 				goto out;
3764 			*p++ = cpu_to_be32(pf);
3765 		} else {
3766 			if (report)
3767 				pr_warn("NFS: SECINFO: security flavor %u "
3768 					"is not supported\n", pf);
3769 		}
3770 	}
3771 
3772 	if (nflavs != supported)
3773 		report = false;
3774 	*flavorsp = htonl(supported);
3775 	nfserr = 0;
3776 out:
3777 	if (exp)
3778 		exp_put(exp);
3779 	return nfserr;
3780 }
3781 
3782 static __be32
3783 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3784 		     struct nfsd4_secinfo *secinfo)
3785 {
3786 	struct xdr_stream *xdr = &resp->xdr;
3787 
3788 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->si_exp);
3789 }
3790 
3791 static __be32
3792 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3793 		     struct nfsd4_secinfo_no_name *secinfo)
3794 {
3795 	struct xdr_stream *xdr = &resp->xdr;
3796 
3797 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->sin_exp);
3798 }
3799 
3800 /*
3801  * The SETATTR encode routine is special -- it always encodes a bitmap,
3802  * regardless of the error status.
3803  */
3804 static __be32
3805 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3806 {
3807 	struct xdr_stream *xdr = &resp->xdr;
3808 	__be32 *p;
3809 
3810 	p = xdr_reserve_space(xdr, 16);
3811 	if (!p)
3812 		return nfserr_resource;
3813 	if (nfserr) {
3814 		*p++ = cpu_to_be32(3);
3815 		*p++ = cpu_to_be32(0);
3816 		*p++ = cpu_to_be32(0);
3817 		*p++ = cpu_to_be32(0);
3818 	}
3819 	else {
3820 		*p++ = cpu_to_be32(3);
3821 		*p++ = cpu_to_be32(setattr->sa_bmval[0]);
3822 		*p++ = cpu_to_be32(setattr->sa_bmval[1]);
3823 		*p++ = cpu_to_be32(setattr->sa_bmval[2]);
3824 	}
3825 	return nfserr;
3826 }
3827 
3828 static __be32
3829 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3830 {
3831 	struct xdr_stream *xdr = &resp->xdr;
3832 	__be32 *p;
3833 
3834 	if (!nfserr) {
3835 		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
3836 		if (!p)
3837 			return nfserr_resource;
3838 		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
3839 		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
3840 						NFS4_VERIFIER_SIZE);
3841 	}
3842 	else if (nfserr == nfserr_clid_inuse) {
3843 		p = xdr_reserve_space(xdr, 8);
3844 		if (!p)
3845 			return nfserr_resource;
3846 		*p++ = cpu_to_be32(0);
3847 		*p++ = cpu_to_be32(0);
3848 	}
3849 	return nfserr;
3850 }
3851 
3852 static __be32
3853 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3854 {
3855 	struct xdr_stream *xdr = &resp->xdr;
3856 	__be32 *p;
3857 
3858 	if (!nfserr) {
3859 		p = xdr_reserve_space(xdr, 16);
3860 		if (!p)
3861 			return nfserr_resource;
3862 		*p++ = cpu_to_be32(write->wr_bytes_written);
3863 		*p++ = cpu_to_be32(write->wr_how_written);
3864 		p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
3865 							NFS4_VERIFIER_SIZE);
3866 	}
3867 	return nfserr;
3868 }
3869 
3870 static const u32 nfs4_minimal_spo_must_enforce[2] = {
3871 	[1] = 1 << (OP_BIND_CONN_TO_SESSION - 32) |
3872 	      1 << (OP_EXCHANGE_ID - 32) |
3873 	      1 << (OP_CREATE_SESSION - 32) |
3874 	      1 << (OP_DESTROY_SESSION - 32) |
3875 	      1 << (OP_DESTROY_CLIENTID - 32)
3876 };
3877 
3878 static __be32
3879 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
3880 			 struct nfsd4_exchange_id *exid)
3881 {
3882 	struct xdr_stream *xdr = &resp->xdr;
3883 	__be32 *p;
3884 	char *major_id;
3885 	char *server_scope;
3886 	int major_id_sz;
3887 	int server_scope_sz;
3888 	uint64_t minor_id = 0;
3889 
3890 	if (nfserr)
3891 		return nfserr;
3892 
3893 	major_id = utsname()->nodename;
3894 	major_id_sz = strlen(major_id);
3895 	server_scope = utsname()->nodename;
3896 	server_scope_sz = strlen(server_scope);
3897 
3898 	p = xdr_reserve_space(xdr,
3899 		8 /* eir_clientid */ +
3900 		4 /* eir_sequenceid */ +
3901 		4 /* eir_flags */ +
3902 		4 /* spr_how */);
3903 	if (!p)
3904 		return nfserr_resource;
3905 
3906 	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
3907 	*p++ = cpu_to_be32(exid->seqid);
3908 	*p++ = cpu_to_be32(exid->flags);
3909 
3910 	*p++ = cpu_to_be32(exid->spa_how);
3911 
3912 	switch (exid->spa_how) {
3913 	case SP4_NONE:
3914 		break;
3915 	case SP4_MACH_CRED:
3916 		/* spo_must_enforce, spo_must_allow */
3917 		p = xdr_reserve_space(xdr, 16);
3918 		if (!p)
3919 			return nfserr_resource;
3920 
3921 		/* spo_must_enforce bitmap: */
3922 		*p++ = cpu_to_be32(2);
3923 		*p++ = cpu_to_be32(nfs4_minimal_spo_must_enforce[0]);
3924 		*p++ = cpu_to_be32(nfs4_minimal_spo_must_enforce[1]);
3925 		/* empty spo_must_allow bitmap: */
3926 		*p++ = cpu_to_be32(0);
3927 
3928 		break;
3929 	default:
3930 		WARN_ON_ONCE(1);
3931 	}
3932 
3933 	p = xdr_reserve_space(xdr,
3934 		8 /* so_minor_id */ +
3935 		4 /* so_major_id.len */ +
3936 		(XDR_QUADLEN(major_id_sz) * 4) +
3937 		4 /* eir_server_scope.len */ +
3938 		(XDR_QUADLEN(server_scope_sz) * 4) +
3939 		4 /* eir_server_impl_id.count (0) */);
3940 	if (!p)
3941 		return nfserr_resource;
3942 
3943 	/* The server_owner struct */
3944 	p = xdr_encode_hyper(p, minor_id);      /* Minor id */
3945 	/* major id */
3946 	p = xdr_encode_opaque(p, major_id, major_id_sz);
3947 
3948 	/* Server scope */
3949 	p = xdr_encode_opaque(p, server_scope, server_scope_sz);
3950 
3951 	/* Implementation id */
3952 	*p++ = cpu_to_be32(0);	/* zero length nfs_impl_id4 array */
3953 	return 0;
3954 }
3955 
3956 static __be32
3957 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
3958 			    struct nfsd4_create_session *sess)
3959 {
3960 	struct xdr_stream *xdr = &resp->xdr;
3961 	__be32 *p;
3962 
3963 	if (nfserr)
3964 		return nfserr;
3965 
3966 	p = xdr_reserve_space(xdr, 24);
3967 	if (!p)
3968 		return nfserr_resource;
3969 	p = xdr_encode_opaque_fixed(p, sess->sessionid.data,
3970 					NFS4_MAX_SESSIONID_LEN);
3971 	*p++ = cpu_to_be32(sess->seqid);
3972 	*p++ = cpu_to_be32(sess->flags);
3973 
3974 	p = xdr_reserve_space(xdr, 28);
3975 	if (!p)
3976 		return nfserr_resource;
3977 	*p++ = cpu_to_be32(0); /* headerpadsz */
3978 	*p++ = cpu_to_be32(sess->fore_channel.maxreq_sz);
3979 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_sz);
3980 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_cached);
3981 	*p++ = cpu_to_be32(sess->fore_channel.maxops);
3982 	*p++ = cpu_to_be32(sess->fore_channel.maxreqs);
3983 	*p++ = cpu_to_be32(sess->fore_channel.nr_rdma_attrs);
3984 
3985 	if (sess->fore_channel.nr_rdma_attrs) {
3986 		p = xdr_reserve_space(xdr, 4);
3987 		if (!p)
3988 			return nfserr_resource;
3989 		*p++ = cpu_to_be32(sess->fore_channel.rdma_attrs);
3990 	}
3991 
3992 	p = xdr_reserve_space(xdr, 28);
3993 	if (!p)
3994 		return nfserr_resource;
3995 	*p++ = cpu_to_be32(0); /* headerpadsz */
3996 	*p++ = cpu_to_be32(sess->back_channel.maxreq_sz);
3997 	*p++ = cpu_to_be32(sess->back_channel.maxresp_sz);
3998 	*p++ = cpu_to_be32(sess->back_channel.maxresp_cached);
3999 	*p++ = cpu_to_be32(sess->back_channel.maxops);
4000 	*p++ = cpu_to_be32(sess->back_channel.maxreqs);
4001 	*p++ = cpu_to_be32(sess->back_channel.nr_rdma_attrs);
4002 
4003 	if (sess->back_channel.nr_rdma_attrs) {
4004 		p = xdr_reserve_space(xdr, 4);
4005 		if (!p)
4006 			return nfserr_resource;
4007 		*p++ = cpu_to_be32(sess->back_channel.rdma_attrs);
4008 	}
4009 	return 0;
4010 }
4011 
4012 static __be32
4013 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
4014 		      struct nfsd4_sequence *seq)
4015 {
4016 	struct xdr_stream *xdr = &resp->xdr;
4017 	__be32 *p;
4018 
4019 	if (nfserr)
4020 		return nfserr;
4021 
4022 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 20);
4023 	if (!p)
4024 		return nfserr_resource;
4025 	p = xdr_encode_opaque_fixed(p, seq->sessionid.data,
4026 					NFS4_MAX_SESSIONID_LEN);
4027 	*p++ = cpu_to_be32(seq->seqid);
4028 	*p++ = cpu_to_be32(seq->slotid);
4029 	/* Note slotid's are numbered from zero: */
4030 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_highest_slotid */
4031 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_target_highest_slotid */
4032 	*p++ = cpu_to_be32(seq->status_flags);
4033 
4034 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
4035 	return 0;
4036 }
4037 
4038 static __be32
4039 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
4040 			  struct nfsd4_test_stateid *test_stateid)
4041 {
4042 	struct xdr_stream *xdr = &resp->xdr;
4043 	struct nfsd4_test_stateid_id *stateid, *next;
4044 	__be32 *p;
4045 
4046 	if (nfserr)
4047 		return nfserr;
4048 
4049 	p = xdr_reserve_space(xdr, 4 + (4 * test_stateid->ts_num_ids));
4050 	if (!p)
4051 		return nfserr_resource;
4052 	*p++ = htonl(test_stateid->ts_num_ids);
4053 
4054 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
4055 		*p++ = stateid->ts_id_status;
4056 	}
4057 
4058 	return nfserr;
4059 }
4060 
4061 #ifdef CONFIG_NFSD_PNFS
4062 static __be32
4063 nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
4064 		struct nfsd4_getdeviceinfo *gdev)
4065 {
4066 	struct xdr_stream *xdr = &resp->xdr;
4067 	const struct nfsd4_layout_ops *ops =
4068 		nfsd4_layout_ops[gdev->gd_layout_type];
4069 	u32 starting_len = xdr->buf->len, needed_len;
4070 	__be32 *p;
4071 
4072 	dprintk("%s: err %d\n", __func__, nfserr);
4073 	if (nfserr)
4074 		goto out;
4075 
4076 	nfserr = nfserr_resource;
4077 	p = xdr_reserve_space(xdr, 4);
4078 	if (!p)
4079 		goto out;
4080 
4081 	*p++ = cpu_to_be32(gdev->gd_layout_type);
4082 
4083 	/* If maxcount is 0 then just update notifications */
4084 	if (gdev->gd_maxcount != 0) {
4085 		nfserr = ops->encode_getdeviceinfo(xdr, gdev);
4086 		if (nfserr) {
4087 			/*
4088 			 * We don't bother to burden the layout drivers with
4089 			 * enforcing gd_maxcount, just tell the client to
4090 			 * come back with a bigger buffer if it's not enough.
4091 			 */
4092 			if (xdr->buf->len + 4 > gdev->gd_maxcount)
4093 				goto toosmall;
4094 			goto out;
4095 		}
4096 	}
4097 
4098 	nfserr = nfserr_resource;
4099 	if (gdev->gd_notify_types) {
4100 		p = xdr_reserve_space(xdr, 4 + 4);
4101 		if (!p)
4102 			goto out;
4103 		*p++ = cpu_to_be32(1);			/* bitmap length */
4104 		*p++ = cpu_to_be32(gdev->gd_notify_types);
4105 	} else {
4106 		p = xdr_reserve_space(xdr, 4);
4107 		if (!p)
4108 			goto out;
4109 		*p++ = 0;
4110 	}
4111 
4112 	nfserr = 0;
4113 out:
4114 	kfree(gdev->gd_device);
4115 	dprintk("%s: done: %d\n", __func__, be32_to_cpu(nfserr));
4116 	return nfserr;
4117 
4118 toosmall:
4119 	dprintk("%s: maxcount too small\n", __func__);
4120 	needed_len = xdr->buf->len + 4 /* notifications */;
4121 	xdr_truncate_encode(xdr, starting_len);
4122 	p = xdr_reserve_space(xdr, 4);
4123 	if (!p) {
4124 		nfserr = nfserr_resource;
4125 	} else {
4126 		*p++ = cpu_to_be32(needed_len);
4127 		nfserr = nfserr_toosmall;
4128 	}
4129 	goto out;
4130 }
4131 
4132 static __be32
4133 nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr,
4134 		struct nfsd4_layoutget *lgp)
4135 {
4136 	struct xdr_stream *xdr = &resp->xdr;
4137 	const struct nfsd4_layout_ops *ops =
4138 		nfsd4_layout_ops[lgp->lg_layout_type];
4139 	__be32 *p;
4140 
4141 	dprintk("%s: err %d\n", __func__, nfserr);
4142 	if (nfserr)
4143 		goto out;
4144 
4145 	nfserr = nfserr_resource;
4146 	p = xdr_reserve_space(xdr, 36 + sizeof(stateid_opaque_t));
4147 	if (!p)
4148 		goto out;
4149 
4150 	*p++ = cpu_to_be32(1);	/* we always set return-on-close */
4151 	*p++ = cpu_to_be32(lgp->lg_sid.si_generation);
4152 	p = xdr_encode_opaque_fixed(p, &lgp->lg_sid.si_opaque,
4153 				    sizeof(stateid_opaque_t));
4154 
4155 	*p++ = cpu_to_be32(1);	/* we always return a single layout */
4156 	p = xdr_encode_hyper(p, lgp->lg_seg.offset);
4157 	p = xdr_encode_hyper(p, lgp->lg_seg.length);
4158 	*p++ = cpu_to_be32(lgp->lg_seg.iomode);
4159 	*p++ = cpu_to_be32(lgp->lg_layout_type);
4160 
4161 	nfserr = ops->encode_layoutget(xdr, lgp);
4162 out:
4163 	kfree(lgp->lg_content);
4164 	return nfserr;
4165 }
4166 
4167 static __be32
4168 nfsd4_encode_layoutcommit(struct nfsd4_compoundres *resp, __be32 nfserr,
4169 			  struct nfsd4_layoutcommit *lcp)
4170 {
4171 	struct xdr_stream *xdr = &resp->xdr;
4172 	__be32 *p;
4173 
4174 	if (nfserr)
4175 		return nfserr;
4176 
4177 	p = xdr_reserve_space(xdr, 4);
4178 	if (!p)
4179 		return nfserr_resource;
4180 	*p++ = cpu_to_be32(lcp->lc_size_chg);
4181 	if (lcp->lc_size_chg) {
4182 		p = xdr_reserve_space(xdr, 8);
4183 		if (!p)
4184 			return nfserr_resource;
4185 		p = xdr_encode_hyper(p, lcp->lc_newsize);
4186 	}
4187 
4188 	return nfs_ok;
4189 }
4190 
4191 static __be32
4192 nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
4193 		struct nfsd4_layoutreturn *lrp)
4194 {
4195 	struct xdr_stream *xdr = &resp->xdr;
4196 	__be32 *p;
4197 
4198 	if (nfserr)
4199 		return nfserr;
4200 
4201 	p = xdr_reserve_space(xdr, 4);
4202 	if (!p)
4203 		return nfserr_resource;
4204 	*p++ = cpu_to_be32(lrp->lrs_present);
4205 	if (lrp->lrs_present)
4206 		return nfsd4_encode_stateid(xdr, &lrp->lr_sid);
4207 	return nfs_ok;
4208 }
4209 #endif /* CONFIG_NFSD_PNFS */
4210 
4211 static __be32
4212 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
4213 		  struct nfsd4_seek *seek)
4214 {
4215 	__be32 *p;
4216 
4217 	if (nfserr)
4218 		return nfserr;
4219 
4220 	p = xdr_reserve_space(&resp->xdr, 4 + 8);
4221 	*p++ = cpu_to_be32(seek->seek_eof);
4222 	p = xdr_encode_hyper(p, seek->seek_pos);
4223 
4224 	return nfserr;
4225 }
4226 
4227 static __be32
4228 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
4229 {
4230 	return nfserr;
4231 }
4232 
4233 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
4234 
4235 /*
4236  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
4237  * since we don't need to filter out obsolete ops as this is
4238  * done in the decoding phase.
4239  */
4240 static nfsd4_enc nfsd4_enc_ops[] = {
4241 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
4242 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
4243 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
4244 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
4245 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
4246 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4247 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
4248 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
4249 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
4250 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
4251 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
4252 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
4253 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
4254 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
4255 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4256 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
4257 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
4258 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
4259 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
4260 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4261 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
4262 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4263 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
4264 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
4265 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
4266 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
4267 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
4268 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
4269 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
4270 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
4271 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
4272 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
4273 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
4274 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
4275 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4276 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
4277 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
4278 
4279 	/* NFSv4.1 operations */
4280 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
4281 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
4282 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
4283 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
4284 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
4285 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
4286 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4287 #ifdef CONFIG_NFSD_PNFS
4288 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_getdeviceinfo,
4289 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4290 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_layoutcommit,
4291 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_layoutget,
4292 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_layoutreturn,
4293 #else
4294 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
4295 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4296 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
4297 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
4298 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4299 #endif
4300 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
4301 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
4302 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
4303 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
4304 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4305 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
4306 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
4307 
4308 	/* NFSv4.2 operations */
4309 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4310 	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_noop,
4311 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
4312 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4313 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
4314 	[OP_LAYOUTERROR]	= (nfsd4_enc)nfsd4_encode_noop,
4315 	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,
4316 	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,
4317 	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_noop,
4318 	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_noop,
4319 	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,
4320 	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,
4321 	[OP_CLONE]		= (nfsd4_enc)nfsd4_encode_noop,
4322 };
4323 
4324 /*
4325  * Calculate whether we still have space to encode repsize bytes.
4326  * There are two considerations:
4327  *     - For NFS versions >=4.1, the size of the reply must stay within
4328  *       session limits
4329  *     - For all NFS versions, we must stay within limited preallocated
4330  *       buffer space.
4331  *
4332  * This is called before the operation is processed, so can only provide
4333  * an upper estimate.  For some nonidempotent operations (such as
4334  * getattr), it's not necessarily a problem if that estimate is wrong,
4335  * as we can fail it after processing without significant side effects.
4336  */
4337 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
4338 {
4339 	struct xdr_buf *buf = &resp->rqstp->rq_res;
4340 	struct nfsd4_slot *slot = resp->cstate.slot;
4341 
4342 	if (buf->len + respsize <= buf->buflen)
4343 		return nfs_ok;
4344 	if (!nfsd4_has_session(&resp->cstate))
4345 		return nfserr_resource;
4346 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
4347 		WARN_ON_ONCE(1);
4348 		return nfserr_rep_too_big_to_cache;
4349 	}
4350 	return nfserr_rep_too_big;
4351 }
4352 
4353 void
4354 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
4355 {
4356 	struct xdr_stream *xdr = &resp->xdr;
4357 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
4358 	struct svc_rqst *rqstp = resp->rqstp;
4359 	int post_err_offset;
4360 	nfsd4_enc encoder;
4361 	__be32 *p;
4362 
4363 	p = xdr_reserve_space(xdr, 8);
4364 	if (!p) {
4365 		WARN_ON_ONCE(1);
4366 		return;
4367 	}
4368 	*p++ = cpu_to_be32(op->opnum);
4369 	post_err_offset = xdr->buf->len;
4370 
4371 	if (op->opnum == OP_ILLEGAL)
4372 		goto status;
4373 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
4374 	       !nfsd4_enc_ops[op->opnum]);
4375 	encoder = nfsd4_enc_ops[op->opnum];
4376 	op->status = encoder(resp, op->status, &op->u);
4377 	xdr_commit_encode(xdr);
4378 
4379 	/* nfsd4_check_resp_size guarantees enough room for error status */
4380 	if (!op->status) {
4381 		int space_needed = 0;
4382 		if (!nfsd4_last_compound_op(rqstp))
4383 			space_needed = COMPOUND_ERR_SLACK_SPACE;
4384 		op->status = nfsd4_check_resp_size(resp, space_needed);
4385 	}
4386 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
4387 		struct nfsd4_slot *slot = resp->cstate.slot;
4388 
4389 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
4390 			op->status = nfserr_rep_too_big_to_cache;
4391 		else
4392 			op->status = nfserr_rep_too_big;
4393 	}
4394 	if (op->status == nfserr_resource ||
4395 	    op->status == nfserr_rep_too_big ||
4396 	    op->status == nfserr_rep_too_big_to_cache) {
4397 		/*
4398 		 * The operation may have already been encoded or
4399 		 * partially encoded.  No op returns anything additional
4400 		 * in the case of one of these three errors, so we can
4401 		 * just truncate back to after the status.  But it's a
4402 		 * bug if we had to do this on a non-idempotent op:
4403 		 */
4404 		warn_on_nonidempotent_op(op);
4405 		xdr_truncate_encode(xdr, post_err_offset);
4406 	}
4407 	if (so) {
4408 		int len = xdr->buf->len - post_err_offset;
4409 
4410 		so->so_replay.rp_status = op->status;
4411 		so->so_replay.rp_buflen = len;
4412 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
4413 						so->so_replay.rp_buf, len);
4414 	}
4415 status:
4416 	/* Note that op->status is already in network byte order: */
4417 	write_bytes_to_xdr_buf(xdr->buf, post_err_offset - 4, &op->status, 4);
4418 }
4419 
4420 /*
4421  * Encode the reply stored in the stateowner reply cache
4422  *
4423  * XDR note: do not encode rp->rp_buflen: the buffer contains the
4424  * previously sent already encoded operation.
4425  */
4426 void
4427 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
4428 {
4429 	__be32 *p;
4430 	struct nfs4_replay *rp = op->replay;
4431 
4432 	BUG_ON(!rp);
4433 
4434 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
4435 	if (!p) {
4436 		WARN_ON_ONCE(1);
4437 		return;
4438 	}
4439 	*p++ = cpu_to_be32(op->opnum);
4440 	*p++ = rp->rp_status;  /* already xdr'ed */
4441 
4442 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
4443 }
4444 
4445 int
4446 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
4447 {
4448         return xdr_ressize_check(rqstp, p);
4449 }
4450 
4451 int nfsd4_release_compoundargs(void *rq, __be32 *p, void *resp)
4452 {
4453 	struct svc_rqst *rqstp = rq;
4454 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4455 
4456 	if (args->ops != args->iops) {
4457 		kfree(args->ops);
4458 		args->ops = args->iops;
4459 	}
4460 	kfree(args->tmpp);
4461 	args->tmpp = NULL;
4462 	while (args->to_free) {
4463 		struct svcxdr_tmpbuf *tb = args->to_free;
4464 		args->to_free = tb->next;
4465 		kfree(tb);
4466 	}
4467 	return 1;
4468 }
4469 
4470 int
4471 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundargs *args)
4472 {
4473 	if (rqstp->rq_arg.head[0].iov_len % 4) {
4474 		/* client is nuts */
4475 		dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)",
4476 			__func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid));
4477 		return 0;
4478 	}
4479 	args->p = p;
4480 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
4481 	args->pagelist = rqstp->rq_arg.pages;
4482 	args->pagelen = rqstp->rq_arg.page_len;
4483 	args->tmpp = NULL;
4484 	args->to_free = NULL;
4485 	args->ops = args->iops;
4486 	args->rqstp = rqstp;
4487 
4488 	return !nfsd4_decode_compound(args);
4489 }
4490 
4491 int
4492 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundres *resp)
4493 {
4494 	/*
4495 	 * All that remains is to write the tag and operation count...
4496 	 */
4497 	struct xdr_buf *buf = resp->xdr.buf;
4498 
4499 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
4500 				 buf->tail[0].iov_len);
4501 
4502 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
4503 
4504 	p = resp->tagp;
4505 	*p++ = htonl(resp->taglen);
4506 	memcpy(p, resp->tag, resp->taglen);
4507 	p += XDR_QUADLEN(resp->taglen);
4508 	*p++ = htonl(resp->opcnt);
4509 
4510 	nfsd4_sequence_done(resp);
4511 	return 1;
4512 }
4513 
4514 /*
4515  * Local variables:
4516  *  c-basic-offset: 8
4517  * End:
4518  */
4519