xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision 2572f00d)
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 + 4);
1076 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1077 	rename->rn_tnamelen = be32_to_cpup(p++);
1078 	READ_BUF(rename->rn_tnamelen);
1079 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1080 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1081 		return status;
1082 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1083 		return status;
1084 
1085 	DECODE_TAIL;
1086 }
1087 
1088 static __be32
1089 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1090 {
1091 	DECODE_HEAD;
1092 
1093 	if (argp->minorversion >= 1)
1094 		return nfserr_notsupp;
1095 
1096 	READ_BUF(sizeof(clientid_t));
1097 	COPYMEM(clientid, sizeof(clientid_t));
1098 
1099 	DECODE_TAIL;
1100 }
1101 
1102 static __be32
1103 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1104 		     struct nfsd4_secinfo *secinfo)
1105 {
1106 	DECODE_HEAD;
1107 
1108 	READ_BUF(4);
1109 	secinfo->si_namelen = be32_to_cpup(p++);
1110 	READ_BUF(secinfo->si_namelen);
1111 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1112 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1113 	if (status)
1114 		return status;
1115 	DECODE_TAIL;
1116 }
1117 
1118 static __be32
1119 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1120 		     struct nfsd4_secinfo_no_name *sin)
1121 {
1122 	DECODE_HEAD;
1123 
1124 	READ_BUF(4);
1125 	sin->sin_style = be32_to_cpup(p++);
1126 	DECODE_TAIL;
1127 }
1128 
1129 static __be32
1130 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1131 {
1132 	__be32 status;
1133 
1134 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1135 	if (status)
1136 		return status;
1137 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1138 				  &setattr->sa_acl, &setattr->sa_label);
1139 }
1140 
1141 static __be32
1142 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1143 {
1144 	DECODE_HEAD;
1145 
1146 	if (argp->minorversion >= 1)
1147 		return nfserr_notsupp;
1148 
1149 	READ_BUF(NFS4_VERIFIER_SIZE);
1150 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1151 
1152 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1153 	if (status)
1154 		return nfserr_bad_xdr;
1155 	READ_BUF(8);
1156 	setclientid->se_callback_prog = be32_to_cpup(p++);
1157 	setclientid->se_callback_netid_len = be32_to_cpup(p++);
1158 
1159 	READ_BUF(setclientid->se_callback_netid_len + 4);
1160 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1161 	setclientid->se_callback_addr_len = be32_to_cpup(p++);
1162 
1163 	READ_BUF(setclientid->se_callback_addr_len + 4);
1164 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1165 	setclientid->se_callback_ident = be32_to_cpup(p++);
1166 
1167 	DECODE_TAIL;
1168 }
1169 
1170 static __be32
1171 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1172 {
1173 	DECODE_HEAD;
1174 
1175 	if (argp->minorversion >= 1)
1176 		return nfserr_notsupp;
1177 
1178 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1179 	COPYMEM(&scd_c->sc_clientid, 8);
1180 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1181 
1182 	DECODE_TAIL;
1183 }
1184 
1185 /* Also used for NVERIFY */
1186 static __be32
1187 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1188 {
1189 	DECODE_HEAD;
1190 
1191 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1192 		goto out;
1193 
1194 	/* For convenience's sake, we compare raw xdr'd attributes in
1195 	 * nfsd4_proc_verify */
1196 
1197 	READ_BUF(4);
1198 	verify->ve_attrlen = be32_to_cpup(p++);
1199 	READ_BUF(verify->ve_attrlen);
1200 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1201 
1202 	DECODE_TAIL;
1203 }
1204 
1205 static __be32
1206 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1207 {
1208 	int avail;
1209 	int len;
1210 	DECODE_HEAD;
1211 
1212 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1213 	if (status)
1214 		return status;
1215 	READ_BUF(16);
1216 	p = xdr_decode_hyper(p, &write->wr_offset);
1217 	write->wr_stable_how = be32_to_cpup(p++);
1218 	if (write->wr_stable_how > 2)
1219 		goto xdr_error;
1220 	write->wr_buflen = be32_to_cpup(p++);
1221 
1222 	/* Sorry .. no magic macros for this.. *
1223 	 * READ_BUF(write->wr_buflen);
1224 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1225 	 */
1226 	avail = (char*)argp->end - (char*)argp->p;
1227 	if (avail + argp->pagelen < write->wr_buflen) {
1228 		dprintk("NFSD: xdr error (%s:%d)\n",
1229 				__FILE__, __LINE__);
1230 		goto xdr_error;
1231 	}
1232 	write->wr_head.iov_base = p;
1233 	write->wr_head.iov_len = avail;
1234 	write->wr_pagelist = argp->pagelist;
1235 
1236 	len = XDR_QUADLEN(write->wr_buflen) << 2;
1237 	if (len >= avail) {
1238 		int pages;
1239 
1240 		len -= avail;
1241 
1242 		pages = len >> PAGE_SHIFT;
1243 		argp->pagelist += pages;
1244 		argp->pagelen -= pages * PAGE_SIZE;
1245 		len -= pages * PAGE_SIZE;
1246 
1247 		argp->p = (__be32 *)page_address(argp->pagelist[0]);
1248 		argp->pagelist++;
1249 		argp->end = argp->p + XDR_QUADLEN(PAGE_SIZE);
1250 	}
1251 	argp->p += XDR_QUADLEN(len);
1252 
1253 	DECODE_TAIL;
1254 }
1255 
1256 static __be32
1257 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1258 {
1259 	DECODE_HEAD;
1260 
1261 	if (argp->minorversion >= 1)
1262 		return nfserr_notsupp;
1263 
1264 	READ_BUF(12);
1265 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1266 	rlockowner->rl_owner.len = be32_to_cpup(p++);
1267 	READ_BUF(rlockowner->rl_owner.len);
1268 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1269 
1270 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1271 		return nfserr_inval;
1272 	DECODE_TAIL;
1273 }
1274 
1275 static __be32
1276 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1277 			 struct nfsd4_exchange_id *exid)
1278 {
1279 	int dummy, tmp;
1280 	DECODE_HEAD;
1281 
1282 	READ_BUF(NFS4_VERIFIER_SIZE);
1283 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1284 
1285 	status = nfsd4_decode_opaque(argp, &exid->clname);
1286 	if (status)
1287 		return nfserr_bad_xdr;
1288 
1289 	READ_BUF(4);
1290 	exid->flags = be32_to_cpup(p++);
1291 
1292 	/* Ignore state_protect4_a */
1293 	READ_BUF(4);
1294 	exid->spa_how = be32_to_cpup(p++);
1295 	switch (exid->spa_how) {
1296 	case SP4_NONE:
1297 		break;
1298 	case SP4_MACH_CRED:
1299 		/* spo_must_enforce */
1300 		READ_BUF(4);
1301 		dummy = be32_to_cpup(p++);
1302 		READ_BUF(dummy * 4);
1303 		p += dummy;
1304 
1305 		/* spo_must_allow */
1306 		READ_BUF(4);
1307 		dummy = be32_to_cpup(p++);
1308 		READ_BUF(dummy * 4);
1309 		p += dummy;
1310 		break;
1311 	case SP4_SSV:
1312 		/* ssp_ops */
1313 		READ_BUF(4);
1314 		dummy = be32_to_cpup(p++);
1315 		READ_BUF(dummy * 4);
1316 		p += dummy;
1317 
1318 		READ_BUF(4);
1319 		dummy = be32_to_cpup(p++);
1320 		READ_BUF(dummy * 4);
1321 		p += dummy;
1322 
1323 		/* ssp_hash_algs<> */
1324 		READ_BUF(4);
1325 		tmp = be32_to_cpup(p++);
1326 		while (tmp--) {
1327 			READ_BUF(4);
1328 			dummy = be32_to_cpup(p++);
1329 			READ_BUF(dummy);
1330 			p += XDR_QUADLEN(dummy);
1331 		}
1332 
1333 		/* ssp_encr_algs<> */
1334 		READ_BUF(4);
1335 		tmp = be32_to_cpup(p++);
1336 		while (tmp--) {
1337 			READ_BUF(4);
1338 			dummy = be32_to_cpup(p++);
1339 			READ_BUF(dummy);
1340 			p += XDR_QUADLEN(dummy);
1341 		}
1342 
1343 		/* ssp_window and ssp_num_gss_handles */
1344 		READ_BUF(8);
1345 		dummy = be32_to_cpup(p++);
1346 		dummy = be32_to_cpup(p++);
1347 		break;
1348 	default:
1349 		goto xdr_error;
1350 	}
1351 
1352 	/* Ignore Implementation ID */
1353 	READ_BUF(4);    /* nfs_impl_id4 array length */
1354 	dummy = be32_to_cpup(p++);
1355 
1356 	if (dummy > 1)
1357 		goto xdr_error;
1358 
1359 	if (dummy == 1) {
1360 		/* nii_domain */
1361 		READ_BUF(4);
1362 		dummy = be32_to_cpup(p++);
1363 		READ_BUF(dummy);
1364 		p += XDR_QUADLEN(dummy);
1365 
1366 		/* nii_name */
1367 		READ_BUF(4);
1368 		dummy = be32_to_cpup(p++);
1369 		READ_BUF(dummy);
1370 		p += XDR_QUADLEN(dummy);
1371 
1372 		/* nii_date */
1373 		READ_BUF(12);
1374 		p += 3;
1375 	}
1376 	DECODE_TAIL;
1377 }
1378 
1379 static __be32
1380 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1381 			    struct nfsd4_create_session *sess)
1382 {
1383 	DECODE_HEAD;
1384 	u32 dummy;
1385 
1386 	READ_BUF(16);
1387 	COPYMEM(&sess->clientid, 8);
1388 	sess->seqid = be32_to_cpup(p++);
1389 	sess->flags = be32_to_cpup(p++);
1390 
1391 	/* Fore channel attrs */
1392 	READ_BUF(28);
1393 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1394 	sess->fore_channel.maxreq_sz = be32_to_cpup(p++);
1395 	sess->fore_channel.maxresp_sz = be32_to_cpup(p++);
1396 	sess->fore_channel.maxresp_cached = be32_to_cpup(p++);
1397 	sess->fore_channel.maxops = be32_to_cpup(p++);
1398 	sess->fore_channel.maxreqs = be32_to_cpup(p++);
1399 	sess->fore_channel.nr_rdma_attrs = be32_to_cpup(p++);
1400 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1401 		READ_BUF(4);
1402 		sess->fore_channel.rdma_attrs = be32_to_cpup(p++);
1403 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1404 		dprintk("Too many fore channel attr bitmaps!\n");
1405 		goto xdr_error;
1406 	}
1407 
1408 	/* Back channel attrs */
1409 	READ_BUF(28);
1410 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1411 	sess->back_channel.maxreq_sz = be32_to_cpup(p++);
1412 	sess->back_channel.maxresp_sz = be32_to_cpup(p++);
1413 	sess->back_channel.maxresp_cached = be32_to_cpup(p++);
1414 	sess->back_channel.maxops = be32_to_cpup(p++);
1415 	sess->back_channel.maxreqs = be32_to_cpup(p++);
1416 	sess->back_channel.nr_rdma_attrs = be32_to_cpup(p++);
1417 	if (sess->back_channel.nr_rdma_attrs == 1) {
1418 		READ_BUF(4);
1419 		sess->back_channel.rdma_attrs = be32_to_cpup(p++);
1420 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1421 		dprintk("Too many back channel attr bitmaps!\n");
1422 		goto xdr_error;
1423 	}
1424 
1425 	READ_BUF(4);
1426 	sess->callback_prog = be32_to_cpup(p++);
1427 	nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1428 	DECODE_TAIL;
1429 }
1430 
1431 static __be32
1432 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1433 			     struct nfsd4_destroy_session *destroy_session)
1434 {
1435 	DECODE_HEAD;
1436 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1437 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1438 
1439 	DECODE_TAIL;
1440 }
1441 
1442 static __be32
1443 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1444 			  struct nfsd4_free_stateid *free_stateid)
1445 {
1446 	DECODE_HEAD;
1447 
1448 	READ_BUF(sizeof(stateid_t));
1449 	free_stateid->fr_stateid.si_generation = be32_to_cpup(p++);
1450 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1451 
1452 	DECODE_TAIL;
1453 }
1454 
1455 static __be32
1456 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1457 		      struct nfsd4_sequence *seq)
1458 {
1459 	DECODE_HEAD;
1460 
1461 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1462 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1463 	seq->seqid = be32_to_cpup(p++);
1464 	seq->slotid = be32_to_cpup(p++);
1465 	seq->maxslots = be32_to_cpup(p++);
1466 	seq->cachethis = be32_to_cpup(p++);
1467 
1468 	DECODE_TAIL;
1469 }
1470 
1471 static __be32
1472 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1473 {
1474 	int i;
1475 	__be32 *p, status;
1476 	struct nfsd4_test_stateid_id *stateid;
1477 
1478 	READ_BUF(4);
1479 	test_stateid->ts_num_ids = ntohl(*p++);
1480 
1481 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1482 
1483 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1484 		stateid = svcxdr_tmpalloc(argp, sizeof(*stateid));
1485 		if (!stateid) {
1486 			status = nfserrno(-ENOMEM);
1487 			goto out;
1488 		}
1489 
1490 		INIT_LIST_HEAD(&stateid->ts_id_list);
1491 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1492 
1493 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1494 		if (status)
1495 			goto out;
1496 	}
1497 
1498 	status = 0;
1499 out:
1500 	return status;
1501 xdr_error:
1502 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1503 	status = nfserr_bad_xdr;
1504 	goto out;
1505 }
1506 
1507 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1508 {
1509 	DECODE_HEAD;
1510 
1511 	READ_BUF(8);
1512 	COPYMEM(&dc->clientid, 8);
1513 
1514 	DECODE_TAIL;
1515 }
1516 
1517 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1518 {
1519 	DECODE_HEAD;
1520 
1521 	READ_BUF(4);
1522 	rc->rca_one_fs = be32_to_cpup(p++);
1523 
1524 	DECODE_TAIL;
1525 }
1526 
1527 #ifdef CONFIG_NFSD_PNFS
1528 static __be32
1529 nfsd4_decode_getdeviceinfo(struct nfsd4_compoundargs *argp,
1530 		struct nfsd4_getdeviceinfo *gdev)
1531 {
1532 	DECODE_HEAD;
1533 	u32 num, i;
1534 
1535 	READ_BUF(sizeof(struct nfsd4_deviceid) + 3 * 4);
1536 	COPYMEM(&gdev->gd_devid, sizeof(struct nfsd4_deviceid));
1537 	gdev->gd_layout_type = be32_to_cpup(p++);
1538 	gdev->gd_maxcount = be32_to_cpup(p++);
1539 	num = be32_to_cpup(p++);
1540 	if (num) {
1541 		READ_BUF(4 * num);
1542 		gdev->gd_notify_types = be32_to_cpup(p++);
1543 		for (i = 1; i < num; i++) {
1544 			if (be32_to_cpup(p++)) {
1545 				status = nfserr_inval;
1546 				goto out;
1547 			}
1548 		}
1549 	}
1550 	DECODE_TAIL;
1551 }
1552 
1553 static __be32
1554 nfsd4_decode_layoutget(struct nfsd4_compoundargs *argp,
1555 		struct nfsd4_layoutget *lgp)
1556 {
1557 	DECODE_HEAD;
1558 
1559 	READ_BUF(36);
1560 	lgp->lg_signal = be32_to_cpup(p++);
1561 	lgp->lg_layout_type = be32_to_cpup(p++);
1562 	lgp->lg_seg.iomode = be32_to_cpup(p++);
1563 	p = xdr_decode_hyper(p, &lgp->lg_seg.offset);
1564 	p = xdr_decode_hyper(p, &lgp->lg_seg.length);
1565 	p = xdr_decode_hyper(p, &lgp->lg_minlength);
1566 
1567 	status = nfsd4_decode_stateid(argp, &lgp->lg_sid);
1568 	if (status)
1569 		return status;
1570 
1571 	READ_BUF(4);
1572 	lgp->lg_maxcount = be32_to_cpup(p++);
1573 
1574 	DECODE_TAIL;
1575 }
1576 
1577 static __be32
1578 nfsd4_decode_layoutcommit(struct nfsd4_compoundargs *argp,
1579 		struct nfsd4_layoutcommit *lcp)
1580 {
1581 	DECODE_HEAD;
1582 	u32 timechange;
1583 
1584 	READ_BUF(20);
1585 	p = xdr_decode_hyper(p, &lcp->lc_seg.offset);
1586 	p = xdr_decode_hyper(p, &lcp->lc_seg.length);
1587 	lcp->lc_reclaim = be32_to_cpup(p++);
1588 
1589 	status = nfsd4_decode_stateid(argp, &lcp->lc_sid);
1590 	if (status)
1591 		return status;
1592 
1593 	READ_BUF(4);
1594 	lcp->lc_newoffset = be32_to_cpup(p++);
1595 	if (lcp->lc_newoffset) {
1596 		READ_BUF(8);
1597 		p = xdr_decode_hyper(p, &lcp->lc_last_wr);
1598 	} else
1599 		lcp->lc_last_wr = 0;
1600 	READ_BUF(4);
1601 	timechange = be32_to_cpup(p++);
1602 	if (timechange) {
1603 		status = nfsd4_decode_time(argp, &lcp->lc_mtime);
1604 		if (status)
1605 			return status;
1606 	} else {
1607 		lcp->lc_mtime.tv_nsec = UTIME_NOW;
1608 	}
1609 	READ_BUF(8);
1610 	lcp->lc_layout_type = be32_to_cpup(p++);
1611 
1612 	/*
1613 	 * Save the layout update in XDR format and let the layout driver deal
1614 	 * with it later.
1615 	 */
1616 	lcp->lc_up_len = be32_to_cpup(p++);
1617 	if (lcp->lc_up_len > 0) {
1618 		READ_BUF(lcp->lc_up_len);
1619 		READMEM(lcp->lc_up_layout, lcp->lc_up_len);
1620 	}
1621 
1622 	DECODE_TAIL;
1623 }
1624 
1625 static __be32
1626 nfsd4_decode_layoutreturn(struct nfsd4_compoundargs *argp,
1627 		struct nfsd4_layoutreturn *lrp)
1628 {
1629 	DECODE_HEAD;
1630 
1631 	READ_BUF(16);
1632 	lrp->lr_reclaim = be32_to_cpup(p++);
1633 	lrp->lr_layout_type = be32_to_cpup(p++);
1634 	lrp->lr_seg.iomode = be32_to_cpup(p++);
1635 	lrp->lr_return_type = be32_to_cpup(p++);
1636 	if (lrp->lr_return_type == RETURN_FILE) {
1637 		READ_BUF(16);
1638 		p = xdr_decode_hyper(p, &lrp->lr_seg.offset);
1639 		p = xdr_decode_hyper(p, &lrp->lr_seg.length);
1640 
1641 		status = nfsd4_decode_stateid(argp, &lrp->lr_sid);
1642 		if (status)
1643 			return status;
1644 
1645 		READ_BUF(4);
1646 		lrp->lrf_body_len = be32_to_cpup(p++);
1647 		if (lrp->lrf_body_len > 0) {
1648 			READ_BUF(lrp->lrf_body_len);
1649 			READMEM(lrp->lrf_body, lrp->lrf_body_len);
1650 		}
1651 	} else {
1652 		lrp->lr_seg.offset = 0;
1653 		lrp->lr_seg.length = NFS4_MAX_UINT64;
1654 	}
1655 
1656 	DECODE_TAIL;
1657 }
1658 #endif /* CONFIG_NFSD_PNFS */
1659 
1660 static __be32
1661 nfsd4_decode_fallocate(struct nfsd4_compoundargs *argp,
1662 		       struct nfsd4_fallocate *fallocate)
1663 {
1664 	DECODE_HEAD;
1665 
1666 	status = nfsd4_decode_stateid(argp, &fallocate->falloc_stateid);
1667 	if (status)
1668 		return status;
1669 
1670 	READ_BUF(16);
1671 	p = xdr_decode_hyper(p, &fallocate->falloc_offset);
1672 	xdr_decode_hyper(p, &fallocate->falloc_length);
1673 
1674 	DECODE_TAIL;
1675 }
1676 
1677 static __be32
1678 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
1679 {
1680 	DECODE_HEAD;
1681 
1682 	status = nfsd4_decode_stateid(argp, &seek->seek_stateid);
1683 	if (status)
1684 		return status;
1685 
1686 	READ_BUF(8 + 4);
1687 	p = xdr_decode_hyper(p, &seek->seek_offset);
1688 	seek->seek_whence = be32_to_cpup(p);
1689 
1690 	DECODE_TAIL;
1691 }
1692 
1693 static __be32
1694 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1695 {
1696 	return nfs_ok;
1697 }
1698 
1699 static __be32
1700 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1701 {
1702 	return nfserr_notsupp;
1703 }
1704 
1705 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1706 
1707 static nfsd4_dec nfsd4_dec_ops[] = {
1708 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1709 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1710 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1711 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1712 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1713 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1714 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1715 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1716 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1717 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1718 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1719 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1720 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1721 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1722 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1723 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1724 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1725 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1726 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1727 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1728 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_putpubfh,
1729 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1730 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1731 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1732 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1733 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1734 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1735 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1736 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1737 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1738 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1739 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1740 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1741 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1742 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1743 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1744 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1745 
1746 	/* new operations for NFSv4.1 */
1747 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_backchannel_ctl,
1748 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1749 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1750 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1751 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1752 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
1753 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1754 #ifdef CONFIG_NFSD_PNFS
1755 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_getdeviceinfo,
1756 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1757 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_layoutcommit,
1758 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_layoutget,
1759 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_layoutreturn,
1760 #else
1761 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1762 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1763 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1764 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1765 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1766 #endif
1767 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1768 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1769 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1770 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
1771 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1772 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
1773 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1774 
1775 	/* new operations for NFSv4.2 */
1776 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1777 	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_notsupp,
1778 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
1779 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1780 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1781 	[OP_LAYOUTERROR]	= (nfsd4_dec)nfsd4_decode_notsupp,
1782 	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1783 	[OP_OFFLOAD_CANCEL]	= (nfsd4_dec)nfsd4_decode_notsupp,
1784 	[OP_OFFLOAD_STATUS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1785 	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_notsupp,
1786 	[OP_SEEK]		= (nfsd4_dec)nfsd4_decode_seek,
1787 	[OP_WRITE_SAME]		= (nfsd4_dec)nfsd4_decode_notsupp,
1788 };
1789 
1790 static inline bool
1791 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
1792 {
1793 	if (op->opnum < FIRST_NFS4_OP)
1794 		return false;
1795 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
1796 		return false;
1797 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
1798 		return false;
1799 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
1800 		return false;
1801 	return true;
1802 }
1803 
1804 static __be32
1805 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1806 {
1807 	DECODE_HEAD;
1808 	struct nfsd4_op *op;
1809 	bool cachethis = false;
1810 	int auth_slack= argp->rqstp->rq_auth_slack;
1811 	int max_reply = auth_slack + 8; /* opcnt, status */
1812 	int readcount = 0;
1813 	int readbytes = 0;
1814 	int i;
1815 
1816 	READ_BUF(4);
1817 	argp->taglen = be32_to_cpup(p++);
1818 	READ_BUF(argp->taglen + 8);
1819 	SAVEMEM(argp->tag, argp->taglen);
1820 	argp->minorversion = be32_to_cpup(p++);
1821 	argp->opcnt = be32_to_cpup(p++);
1822 	max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
1823 
1824 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1825 		goto xdr_error;
1826 	if (argp->opcnt > 100)
1827 		goto xdr_error;
1828 
1829 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1830 		argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1831 		if (!argp->ops) {
1832 			argp->ops = argp->iops;
1833 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1834 			goto xdr_error;
1835 		}
1836 	}
1837 
1838 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
1839 		argp->opcnt = 0;
1840 
1841 	for (i = 0; i < argp->opcnt; i++) {
1842 		op = &argp->ops[i];
1843 		op->replay = NULL;
1844 
1845 		READ_BUF(4);
1846 		op->opnum = be32_to_cpup(p++);
1847 
1848 		if (nfsd4_opnum_in_range(argp, op))
1849 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
1850 		else {
1851 			op->opnum = OP_ILLEGAL;
1852 			op->status = nfserr_op_illegal;
1853 		}
1854 		/*
1855 		 * We'll try to cache the result in the DRC if any one
1856 		 * op in the compound wants to be cached:
1857 		 */
1858 		cachethis |= nfsd4_cache_this_op(op);
1859 
1860 		if (op->opnum == OP_READ) {
1861 			readcount++;
1862 			readbytes += nfsd4_max_reply(argp->rqstp, op);
1863 		} else
1864 			max_reply += nfsd4_max_reply(argp->rqstp, op);
1865 		/*
1866 		 * OP_LOCK may return a conflicting lock.  (Special case
1867 		 * because it will just skip encoding this if it runs
1868 		 * out of xdr buffer space, and it is the only operation
1869 		 * that behaves this way.)
1870 		 */
1871 		if (op->opnum == OP_LOCK)
1872 			max_reply += NFS4_OPAQUE_LIMIT;
1873 
1874 		if (op->status) {
1875 			argp->opcnt = i+1;
1876 			break;
1877 		}
1878 	}
1879 	/* Sessions make the DRC unnecessary: */
1880 	if (argp->minorversion)
1881 		cachethis = false;
1882 	svc_reserve(argp->rqstp, max_reply + readbytes);
1883 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1884 
1885 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
1886 		clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
1887 
1888 	DECODE_TAIL;
1889 }
1890 
1891 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode)
1892 {
1893 	if (IS_I_VERSION(inode)) {
1894 		p = xdr_encode_hyper(p, inode->i_version);
1895 	} else {
1896 		*p++ = cpu_to_be32(stat->ctime.tv_sec);
1897 		*p++ = cpu_to_be32(stat->ctime.tv_nsec);
1898 	}
1899 	return p;
1900 }
1901 
1902 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
1903 {
1904 	*p++ = cpu_to_be32(c->atomic);
1905 	if (c->change_supported) {
1906 		p = xdr_encode_hyper(p, c->before_change);
1907 		p = xdr_encode_hyper(p, c->after_change);
1908 	} else {
1909 		*p++ = cpu_to_be32(c->before_ctime_sec);
1910 		*p++ = cpu_to_be32(c->before_ctime_nsec);
1911 		*p++ = cpu_to_be32(c->after_ctime_sec);
1912 		*p++ = cpu_to_be32(c->after_ctime_nsec);
1913 	}
1914 	return p;
1915 }
1916 
1917 /* Encode as an array of strings the string given with components
1918  * separated @sep, escaped with esc_enter and esc_exit.
1919  */
1920 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
1921 					  char *components, char esc_enter,
1922 					  char esc_exit)
1923 {
1924 	__be32 *p;
1925 	__be32 pathlen;
1926 	int pathlen_offset;
1927 	int strlen, count=0;
1928 	char *str, *end, *next;
1929 
1930 	dprintk("nfsd4_encode_components(%s)\n", components);
1931 
1932 	pathlen_offset = xdr->buf->len;
1933 	p = xdr_reserve_space(xdr, 4);
1934 	if (!p)
1935 		return nfserr_resource;
1936 	p++; /* We will fill this in with @count later */
1937 
1938 	end = str = components;
1939 	while (*end) {
1940 		bool found_esc = false;
1941 
1942 		/* try to parse as esc_start, ..., esc_end, sep */
1943 		if (*str == esc_enter) {
1944 			for (; *end && (*end != esc_exit); end++)
1945 				/* find esc_exit or end of string */;
1946 			next = end + 1;
1947 			if (*end && (!*next || *next == sep)) {
1948 				str++;
1949 				found_esc = true;
1950 			}
1951 		}
1952 
1953 		if (!found_esc)
1954 			for (; *end && (*end != sep); end++)
1955 				/* find sep or end of string */;
1956 
1957 		strlen = end - str;
1958 		if (strlen) {
1959 			p = xdr_reserve_space(xdr, strlen + 4);
1960 			if (!p)
1961 				return nfserr_resource;
1962 			p = xdr_encode_opaque(p, str, strlen);
1963 			count++;
1964 		}
1965 		else
1966 			end++;
1967 		if (found_esc)
1968 			end = next;
1969 
1970 		str = end;
1971 	}
1972 	pathlen = htonl(count);
1973 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
1974 	return 0;
1975 }
1976 
1977 /* Encode as an array of strings the string given with components
1978  * separated @sep.
1979  */
1980 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
1981 				      char *components)
1982 {
1983 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
1984 }
1985 
1986 /*
1987  * encode a location element of a fs_locations structure
1988  */
1989 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
1990 					struct nfsd4_fs_location *location)
1991 {
1992 	__be32 status;
1993 
1994 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
1995 						'[', ']');
1996 	if (status)
1997 		return status;
1998 	status = nfsd4_encode_components(xdr, '/', location->path);
1999 	if (status)
2000 		return status;
2001 	return 0;
2002 }
2003 
2004 /*
2005  * Encode a path in RFC3530 'pathname4' format
2006  */
2007 static __be32 nfsd4_encode_path(struct xdr_stream *xdr,
2008 				const struct path *root,
2009 				const struct path *path)
2010 {
2011 	struct path cur = *path;
2012 	__be32 *p;
2013 	struct dentry **components = NULL;
2014 	unsigned int ncomponents = 0;
2015 	__be32 err = nfserr_jukebox;
2016 
2017 	dprintk("nfsd4_encode_components(");
2018 
2019 	path_get(&cur);
2020 	/* First walk the path up to the nfsd root, and store the
2021 	 * dentries/path components in an array.
2022 	 */
2023 	for (;;) {
2024 		if (path_equal(&cur, root))
2025 			break;
2026 		if (cur.dentry == cur.mnt->mnt_root) {
2027 			if (follow_up(&cur))
2028 				continue;
2029 			goto out_free;
2030 		}
2031 		if ((ncomponents & 15) == 0) {
2032 			struct dentry **new;
2033 			new = krealloc(components,
2034 					sizeof(*new) * (ncomponents + 16),
2035 					GFP_KERNEL);
2036 			if (!new)
2037 				goto out_free;
2038 			components = new;
2039 		}
2040 		components[ncomponents++] = cur.dentry;
2041 		cur.dentry = dget_parent(cur.dentry);
2042 	}
2043 	err = nfserr_resource;
2044 	p = xdr_reserve_space(xdr, 4);
2045 	if (!p)
2046 		goto out_free;
2047 	*p++ = cpu_to_be32(ncomponents);
2048 
2049 	while (ncomponents) {
2050 		struct dentry *dentry = components[ncomponents - 1];
2051 		unsigned int len;
2052 
2053 		spin_lock(&dentry->d_lock);
2054 		len = dentry->d_name.len;
2055 		p = xdr_reserve_space(xdr, len + 4);
2056 		if (!p) {
2057 			spin_unlock(&dentry->d_lock);
2058 			goto out_free;
2059 		}
2060 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
2061 		dprintk("/%pd", dentry);
2062 		spin_unlock(&dentry->d_lock);
2063 		dput(dentry);
2064 		ncomponents--;
2065 	}
2066 
2067 	err = 0;
2068 out_free:
2069 	dprintk(")\n");
2070 	while (ncomponents)
2071 		dput(components[--ncomponents]);
2072 	kfree(components);
2073 	path_put(&cur);
2074 	return err;
2075 }
2076 
2077 static __be32 nfsd4_encode_fsloc_fsroot(struct xdr_stream *xdr,
2078 			struct svc_rqst *rqstp, const struct path *path)
2079 {
2080 	struct svc_export *exp_ps;
2081 	__be32 res;
2082 
2083 	exp_ps = rqst_find_fsidzero_export(rqstp);
2084 	if (IS_ERR(exp_ps))
2085 		return nfserrno(PTR_ERR(exp_ps));
2086 	res = nfsd4_encode_path(xdr, &exp_ps->ex_path, path);
2087 	exp_put(exp_ps);
2088 	return res;
2089 }
2090 
2091 /*
2092  *  encode a fs_locations structure
2093  */
2094 static __be32 nfsd4_encode_fs_locations(struct xdr_stream *xdr,
2095 			struct svc_rqst *rqstp, struct svc_export *exp)
2096 {
2097 	__be32 status;
2098 	int i;
2099 	__be32 *p;
2100 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
2101 
2102 	status = nfsd4_encode_fsloc_fsroot(xdr, rqstp, &exp->ex_path);
2103 	if (status)
2104 		return status;
2105 	p = xdr_reserve_space(xdr, 4);
2106 	if (!p)
2107 		return nfserr_resource;
2108 	*p++ = cpu_to_be32(fslocs->locations_count);
2109 	for (i=0; i<fslocs->locations_count; i++) {
2110 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
2111 		if (status)
2112 			return status;
2113 	}
2114 	return 0;
2115 }
2116 
2117 static u32 nfs4_file_type(umode_t mode)
2118 {
2119 	switch (mode & S_IFMT) {
2120 	case S_IFIFO:	return NF4FIFO;
2121 	case S_IFCHR:	return NF4CHR;
2122 	case S_IFDIR:	return NF4DIR;
2123 	case S_IFBLK:	return NF4BLK;
2124 	case S_IFLNK:	return NF4LNK;
2125 	case S_IFREG:	return NF4REG;
2126 	case S_IFSOCK:	return NF4SOCK;
2127 	default:	return NF4BAD;
2128 	};
2129 }
2130 
2131 static inline __be32
2132 nfsd4_encode_aclname(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2133 		     struct nfs4_ace *ace)
2134 {
2135 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
2136 		return nfs4_acl_write_who(xdr, ace->whotype);
2137 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
2138 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
2139 	else
2140 		return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
2141 }
2142 
2143 static inline __be32
2144 nfsd4_encode_layout_type(struct xdr_stream *xdr, enum pnfs_layouttype layout_type)
2145 {
2146 	__be32 *p;
2147 
2148 	if (layout_type) {
2149 		p = xdr_reserve_space(xdr, 8);
2150 		if (!p)
2151 			return nfserr_resource;
2152 		*p++ = cpu_to_be32(1);
2153 		*p++ = cpu_to_be32(layout_type);
2154 	} else {
2155 		p = xdr_reserve_space(xdr, 4);
2156 		if (!p)
2157 			return nfserr_resource;
2158 		*p++ = cpu_to_be32(0);
2159 	}
2160 
2161 	return 0;
2162 }
2163 
2164 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
2165 			      FATTR4_WORD0_RDATTR_ERROR)
2166 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
2167 #define WORD2_ABSENT_FS_ATTRS 0
2168 
2169 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2170 static inline __be32
2171 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2172 			    void *context, int len)
2173 {
2174 	__be32 *p;
2175 
2176 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2177 	if (!p)
2178 		return nfserr_resource;
2179 
2180 	/*
2181 	 * For now we use a 0 here to indicate the null translation; in
2182 	 * the future we may place a call to translation code here.
2183 	 */
2184 	*p++ = cpu_to_be32(0); /* lfs */
2185 	*p++ = cpu_to_be32(0); /* pi */
2186 	p = xdr_encode_opaque(p, context, len);
2187 	return 0;
2188 }
2189 #else
2190 static inline __be32
2191 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2192 			    void *context, int len)
2193 { return 0; }
2194 #endif
2195 
2196 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *bmval2, u32 *rdattr_err)
2197 {
2198 	/* As per referral draft:  */
2199 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2200 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2201 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2202 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2203 			*rdattr_err = NFSERR_MOVED;
2204 		else
2205 			return nfserr_moved;
2206 	}
2207 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2208 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2209 	*bmval2 &= WORD2_ABSENT_FS_ATTRS;
2210 	return 0;
2211 }
2212 
2213 
2214 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2215 {
2216 	struct path path = exp->ex_path;
2217 	int err;
2218 
2219 	path_get(&path);
2220 	while (follow_up(&path)) {
2221 		if (path.dentry != path.mnt->mnt_root)
2222 			break;
2223 	}
2224 	err = vfs_getattr(&path, stat);
2225 	path_put(&path);
2226 	return err;
2227 }
2228 
2229 static __be32
2230 nfsd4_encode_bitmap(struct xdr_stream *xdr, u32 bmval0, u32 bmval1, u32 bmval2)
2231 {
2232 	__be32 *p;
2233 
2234 	if (bmval2) {
2235 		p = xdr_reserve_space(xdr, 16);
2236 		if (!p)
2237 			goto out_resource;
2238 		*p++ = cpu_to_be32(3);
2239 		*p++ = cpu_to_be32(bmval0);
2240 		*p++ = cpu_to_be32(bmval1);
2241 		*p++ = cpu_to_be32(bmval2);
2242 	} else if (bmval1) {
2243 		p = xdr_reserve_space(xdr, 12);
2244 		if (!p)
2245 			goto out_resource;
2246 		*p++ = cpu_to_be32(2);
2247 		*p++ = cpu_to_be32(bmval0);
2248 		*p++ = cpu_to_be32(bmval1);
2249 	} else {
2250 		p = xdr_reserve_space(xdr, 8);
2251 		if (!p)
2252 			goto out_resource;
2253 		*p++ = cpu_to_be32(1);
2254 		*p++ = cpu_to_be32(bmval0);
2255 	}
2256 
2257 	return 0;
2258 out_resource:
2259 	return nfserr_resource;
2260 }
2261 
2262 /*
2263  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2264  * ourselves.
2265  */
2266 static __be32
2267 nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
2268 		struct svc_export *exp,
2269 		struct dentry *dentry, u32 *bmval,
2270 		struct svc_rqst *rqstp, int ignore_crossmnt)
2271 {
2272 	u32 bmval0 = bmval[0];
2273 	u32 bmval1 = bmval[1];
2274 	u32 bmval2 = bmval[2];
2275 	struct kstat stat;
2276 	struct svc_fh *tempfh = NULL;
2277 	struct kstatfs statfs;
2278 	__be32 *p;
2279 	int starting_len = xdr->buf->len;
2280 	int attrlen_offset;
2281 	__be32 attrlen;
2282 	u32 dummy;
2283 	u64 dummy64;
2284 	u32 rdattr_err = 0;
2285 	__be32 status;
2286 	int err;
2287 	struct nfs4_acl *acl = NULL;
2288 	void *context = NULL;
2289 	int contextlen;
2290 	bool contextsupport = false;
2291 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2292 	u32 minorversion = resp->cstate.minorversion;
2293 	struct path path = {
2294 		.mnt	= exp->ex_path.mnt,
2295 		.dentry	= dentry,
2296 	};
2297 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2298 
2299 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2300 	BUG_ON(bmval0 & ~nfsd_suppattrs0(minorversion));
2301 	BUG_ON(bmval1 & ~nfsd_suppattrs1(minorversion));
2302 	BUG_ON(bmval2 & ~nfsd_suppattrs2(minorversion));
2303 
2304 	if (exp->ex_fslocs.migrated) {
2305 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &bmval2, &rdattr_err);
2306 		if (status)
2307 			goto out;
2308 	}
2309 
2310 	err = vfs_getattr(&path, &stat);
2311 	if (err)
2312 		goto out_nfserr;
2313 	if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
2314 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
2315 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2316 		       FATTR4_WORD1_SPACE_TOTAL))) {
2317 		err = vfs_statfs(&path, &statfs);
2318 		if (err)
2319 			goto out_nfserr;
2320 	}
2321 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2322 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2323 		status = nfserr_jukebox;
2324 		if (!tempfh)
2325 			goto out;
2326 		fh_init(tempfh, NFS4_FHSIZE);
2327 		status = fh_compose(tempfh, exp, dentry, NULL);
2328 		if (status)
2329 			goto out;
2330 		fhp = tempfh;
2331 	}
2332 	if (bmval0 & FATTR4_WORD0_ACL) {
2333 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2334 		if (err == -EOPNOTSUPP)
2335 			bmval0 &= ~FATTR4_WORD0_ACL;
2336 		else if (err == -EINVAL) {
2337 			status = nfserr_attrnotsupp;
2338 			goto out;
2339 		} else if (err != 0)
2340 			goto out_nfserr;
2341 	}
2342 
2343 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2344 	if ((bmval2 & FATTR4_WORD2_SECURITY_LABEL) ||
2345 	     bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2346 		err = security_inode_getsecctx(d_inode(dentry),
2347 						&context, &contextlen);
2348 		contextsupport = (err == 0);
2349 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2350 			if (err == -EOPNOTSUPP)
2351 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2352 			else if (err)
2353 				goto out_nfserr;
2354 		}
2355 	}
2356 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2357 
2358 	status = nfsd4_encode_bitmap(xdr, bmval0, bmval1, bmval2);
2359 	if (status)
2360 		goto out;
2361 
2362 	attrlen_offset = xdr->buf->len;
2363 	p = xdr_reserve_space(xdr, 4);
2364 	if (!p)
2365 		goto out_resource;
2366 	p++;                /* to be backfilled later */
2367 
2368 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2369 		u32 word0 = nfsd_suppattrs0(minorversion);
2370 		u32 word1 = nfsd_suppattrs1(minorversion);
2371 		u32 word2 = nfsd_suppattrs2(minorversion);
2372 
2373 		if (!IS_POSIXACL(dentry->d_inode))
2374 			word0 &= ~FATTR4_WORD0_ACL;
2375 		if (!contextsupport)
2376 			word2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2377 		if (!word2) {
2378 			p = xdr_reserve_space(xdr, 12);
2379 			if (!p)
2380 				goto out_resource;
2381 			*p++ = cpu_to_be32(2);
2382 			*p++ = cpu_to_be32(word0);
2383 			*p++ = cpu_to_be32(word1);
2384 		} else {
2385 			p = xdr_reserve_space(xdr, 16);
2386 			if (!p)
2387 				goto out_resource;
2388 			*p++ = cpu_to_be32(3);
2389 			*p++ = cpu_to_be32(word0);
2390 			*p++ = cpu_to_be32(word1);
2391 			*p++ = cpu_to_be32(word2);
2392 		}
2393 	}
2394 	if (bmval0 & FATTR4_WORD0_TYPE) {
2395 		p = xdr_reserve_space(xdr, 4);
2396 		if (!p)
2397 			goto out_resource;
2398 		dummy = nfs4_file_type(stat.mode);
2399 		if (dummy == NF4BAD) {
2400 			status = nfserr_serverfault;
2401 			goto out;
2402 		}
2403 		*p++ = cpu_to_be32(dummy);
2404 	}
2405 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2406 		p = xdr_reserve_space(xdr, 4);
2407 		if (!p)
2408 			goto out_resource;
2409 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2410 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT);
2411 		else
2412 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT|
2413 						NFS4_FH_VOL_RENAME);
2414 	}
2415 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2416 		p = xdr_reserve_space(xdr, 8);
2417 		if (!p)
2418 			goto out_resource;
2419 		p = encode_change(p, &stat, d_inode(dentry));
2420 	}
2421 	if (bmval0 & FATTR4_WORD0_SIZE) {
2422 		p = xdr_reserve_space(xdr, 8);
2423 		if (!p)
2424 			goto out_resource;
2425 		p = xdr_encode_hyper(p, stat.size);
2426 	}
2427 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2428 		p = xdr_reserve_space(xdr, 4);
2429 		if (!p)
2430 			goto out_resource;
2431 		*p++ = cpu_to_be32(1);
2432 	}
2433 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2434 		p = xdr_reserve_space(xdr, 4);
2435 		if (!p)
2436 			goto out_resource;
2437 		*p++ = cpu_to_be32(1);
2438 	}
2439 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2440 		p = xdr_reserve_space(xdr, 4);
2441 		if (!p)
2442 			goto out_resource;
2443 		*p++ = cpu_to_be32(0);
2444 	}
2445 	if (bmval0 & FATTR4_WORD0_FSID) {
2446 		p = xdr_reserve_space(xdr, 16);
2447 		if (!p)
2448 			goto out_resource;
2449 		if (exp->ex_fslocs.migrated) {
2450 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
2451 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
2452 		} else switch(fsid_source(fhp)) {
2453 		case FSIDSOURCE_FSID:
2454 			p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
2455 			p = xdr_encode_hyper(p, (u64)0);
2456 			break;
2457 		case FSIDSOURCE_DEV:
2458 			*p++ = cpu_to_be32(0);
2459 			*p++ = cpu_to_be32(MAJOR(stat.dev));
2460 			*p++ = cpu_to_be32(0);
2461 			*p++ = cpu_to_be32(MINOR(stat.dev));
2462 			break;
2463 		case FSIDSOURCE_UUID:
2464 			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
2465 								EX_UUID_LEN);
2466 			break;
2467 		}
2468 	}
2469 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2470 		p = xdr_reserve_space(xdr, 4);
2471 		if (!p)
2472 			goto out_resource;
2473 		*p++ = cpu_to_be32(0);
2474 	}
2475 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2476 		p = xdr_reserve_space(xdr, 4);
2477 		if (!p)
2478 			goto out_resource;
2479 		*p++ = cpu_to_be32(nn->nfsd4_lease);
2480 	}
2481 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2482 		p = xdr_reserve_space(xdr, 4);
2483 		if (!p)
2484 			goto out_resource;
2485 		*p++ = cpu_to_be32(rdattr_err);
2486 	}
2487 	if (bmval0 & FATTR4_WORD0_ACL) {
2488 		struct nfs4_ace *ace;
2489 
2490 		if (acl == NULL) {
2491 			p = xdr_reserve_space(xdr, 4);
2492 			if (!p)
2493 				goto out_resource;
2494 
2495 			*p++ = cpu_to_be32(0);
2496 			goto out_acl;
2497 		}
2498 		p = xdr_reserve_space(xdr, 4);
2499 		if (!p)
2500 			goto out_resource;
2501 		*p++ = cpu_to_be32(acl->naces);
2502 
2503 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2504 			p = xdr_reserve_space(xdr, 4*3);
2505 			if (!p)
2506 				goto out_resource;
2507 			*p++ = cpu_to_be32(ace->type);
2508 			*p++ = cpu_to_be32(ace->flag);
2509 			*p++ = cpu_to_be32(ace->access_mask &
2510 							NFS4_ACE_MASK_ALL);
2511 			status = nfsd4_encode_aclname(xdr, rqstp, ace);
2512 			if (status)
2513 				goto out;
2514 		}
2515 	}
2516 out_acl:
2517 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2518 		p = xdr_reserve_space(xdr, 4);
2519 		if (!p)
2520 			goto out_resource;
2521 		*p++ = cpu_to_be32(IS_POSIXACL(dentry->d_inode) ?
2522 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2523 	}
2524 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2525 		p = xdr_reserve_space(xdr, 4);
2526 		if (!p)
2527 			goto out_resource;
2528 		*p++ = cpu_to_be32(1);
2529 	}
2530 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2531 		p = xdr_reserve_space(xdr, 4);
2532 		if (!p)
2533 			goto out_resource;
2534 		*p++ = cpu_to_be32(0);
2535 	}
2536 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2537 		p = xdr_reserve_space(xdr, 4);
2538 		if (!p)
2539 			goto out_resource;
2540 		*p++ = cpu_to_be32(1);
2541 	}
2542 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2543 		p = xdr_reserve_space(xdr, 4);
2544 		if (!p)
2545 			goto out_resource;
2546 		*p++ = cpu_to_be32(1);
2547 	}
2548 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2549 		p = xdr_reserve_space(xdr, fhp->fh_handle.fh_size + 4);
2550 		if (!p)
2551 			goto out_resource;
2552 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base,
2553 					fhp->fh_handle.fh_size);
2554 	}
2555 	if (bmval0 & FATTR4_WORD0_FILEID) {
2556 		p = xdr_reserve_space(xdr, 8);
2557 		if (!p)
2558 			goto out_resource;
2559 		p = xdr_encode_hyper(p, stat.ino);
2560 	}
2561 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2562 		p = xdr_reserve_space(xdr, 8);
2563 		if (!p)
2564 			goto out_resource;
2565 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2566 	}
2567 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2568 		p = xdr_reserve_space(xdr, 8);
2569 		if (!p)
2570 			goto out_resource;
2571 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2572 	}
2573 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2574 		p = xdr_reserve_space(xdr, 8);
2575 		if (!p)
2576 			goto out_resource;
2577 		p = xdr_encode_hyper(p, (u64) statfs.f_files);
2578 	}
2579 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2580 		status = nfsd4_encode_fs_locations(xdr, rqstp, exp);
2581 		if (status)
2582 			goto out;
2583 	}
2584 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2585 		p = xdr_reserve_space(xdr, 4);
2586 		if (!p)
2587 			goto out_resource;
2588 		*p++ = cpu_to_be32(1);
2589 	}
2590 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2591 		p = xdr_reserve_space(xdr, 8);
2592 		if (!p)
2593 			goto out_resource;
2594 		p = xdr_encode_hyper(p, exp->ex_path.mnt->mnt_sb->s_maxbytes);
2595 	}
2596 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2597 		p = xdr_reserve_space(xdr, 4);
2598 		if (!p)
2599 			goto out_resource;
2600 		*p++ = cpu_to_be32(255);
2601 	}
2602 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2603 		p = xdr_reserve_space(xdr, 4);
2604 		if (!p)
2605 			goto out_resource;
2606 		*p++ = cpu_to_be32(statfs.f_namelen);
2607 	}
2608 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2609 		p = xdr_reserve_space(xdr, 8);
2610 		if (!p)
2611 			goto out_resource;
2612 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2613 	}
2614 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2615 		p = xdr_reserve_space(xdr, 8);
2616 		if (!p)
2617 			goto out_resource;
2618 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2619 	}
2620 	if (bmval1 & FATTR4_WORD1_MODE) {
2621 		p = xdr_reserve_space(xdr, 4);
2622 		if (!p)
2623 			goto out_resource;
2624 		*p++ = cpu_to_be32(stat.mode & S_IALLUGO);
2625 	}
2626 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2627 		p = xdr_reserve_space(xdr, 4);
2628 		if (!p)
2629 			goto out_resource;
2630 		*p++ = cpu_to_be32(1);
2631 	}
2632 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2633 		p = xdr_reserve_space(xdr, 4);
2634 		if (!p)
2635 			goto out_resource;
2636 		*p++ = cpu_to_be32(stat.nlink);
2637 	}
2638 	if (bmval1 & FATTR4_WORD1_OWNER) {
2639 		status = nfsd4_encode_user(xdr, rqstp, stat.uid);
2640 		if (status)
2641 			goto out;
2642 	}
2643 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2644 		status = nfsd4_encode_group(xdr, rqstp, stat.gid);
2645 		if (status)
2646 			goto out;
2647 	}
2648 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2649 		p = xdr_reserve_space(xdr, 8);
2650 		if (!p)
2651 			goto out_resource;
2652 		*p++ = cpu_to_be32((u32) MAJOR(stat.rdev));
2653 		*p++ = cpu_to_be32((u32) MINOR(stat.rdev));
2654 	}
2655 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2656 		p = xdr_reserve_space(xdr, 8);
2657 		if (!p)
2658 			goto out_resource;
2659 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2660 		p = xdr_encode_hyper(p, dummy64);
2661 	}
2662 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2663 		p = xdr_reserve_space(xdr, 8);
2664 		if (!p)
2665 			goto out_resource;
2666 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2667 		p = xdr_encode_hyper(p, dummy64);
2668 	}
2669 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2670 		p = xdr_reserve_space(xdr, 8);
2671 		if (!p)
2672 			goto out_resource;
2673 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2674 		p = xdr_encode_hyper(p, dummy64);
2675 	}
2676 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2677 		p = xdr_reserve_space(xdr, 8);
2678 		if (!p)
2679 			goto out_resource;
2680 		dummy64 = (u64)stat.blocks << 9;
2681 		p = xdr_encode_hyper(p, dummy64);
2682 	}
2683 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2684 		p = xdr_reserve_space(xdr, 12);
2685 		if (!p)
2686 			goto out_resource;
2687 		p = xdr_encode_hyper(p, (s64)stat.atime.tv_sec);
2688 		*p++ = cpu_to_be32(stat.atime.tv_nsec);
2689 	}
2690 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2691 		p = xdr_reserve_space(xdr, 12);
2692 		if (!p)
2693 			goto out_resource;
2694 		*p++ = cpu_to_be32(0);
2695 		*p++ = cpu_to_be32(1);
2696 		*p++ = cpu_to_be32(0);
2697 	}
2698 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2699 		p = xdr_reserve_space(xdr, 12);
2700 		if (!p)
2701 			goto out_resource;
2702 		p = xdr_encode_hyper(p, (s64)stat.ctime.tv_sec);
2703 		*p++ = cpu_to_be32(stat.ctime.tv_nsec);
2704 	}
2705 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2706 		p = xdr_reserve_space(xdr, 12);
2707 		if (!p)
2708 			goto out_resource;
2709 		p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
2710 		*p++ = cpu_to_be32(stat.mtime.tv_nsec);
2711 	}
2712 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2713 		struct kstat parent_stat;
2714 		u64 ino = stat.ino;
2715 
2716 		p = xdr_reserve_space(xdr, 8);
2717 		if (!p)
2718                 	goto out_resource;
2719 		/*
2720 		 * Get parent's attributes if not ignoring crossmount
2721 		 * and this is the root of a cross-mounted filesystem.
2722 		 */
2723 		if (ignore_crossmnt == 0 &&
2724 		    dentry == exp->ex_path.mnt->mnt_root) {
2725 			err = get_parent_attributes(exp, &parent_stat);
2726 			if (err)
2727 				goto out_nfserr;
2728 			ino = parent_stat.ino;
2729 		}
2730 		p = xdr_encode_hyper(p, ino);
2731 	}
2732 #ifdef CONFIG_NFSD_PNFS
2733 	if (bmval1 & FATTR4_WORD1_FS_LAYOUT_TYPES) {
2734 		status = nfsd4_encode_layout_type(xdr, exp->ex_layout_type);
2735 		if (status)
2736 			goto out;
2737 	}
2738 
2739 	if (bmval2 & FATTR4_WORD2_LAYOUT_TYPES) {
2740 		status = nfsd4_encode_layout_type(xdr, exp->ex_layout_type);
2741 		if (status)
2742 			goto out;
2743 	}
2744 
2745 	if (bmval2 & FATTR4_WORD2_LAYOUT_BLKSIZE) {
2746 		p = xdr_reserve_space(xdr, 4);
2747 		if (!p)
2748 			goto out_resource;
2749 		*p++ = cpu_to_be32(stat.blksize);
2750 	}
2751 #endif /* CONFIG_NFSD_PNFS */
2752 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2753 		status = nfsd4_encode_bitmap(xdr, NFSD_SUPPATTR_EXCLCREAT_WORD0,
2754 						  NFSD_SUPPATTR_EXCLCREAT_WORD1,
2755 						  NFSD_SUPPATTR_EXCLCREAT_WORD2);
2756 		if (status)
2757 			goto out;
2758 	}
2759 
2760 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2761 		status = nfsd4_encode_security_label(xdr, rqstp, context,
2762 								contextlen);
2763 		if (status)
2764 			goto out;
2765 	}
2766 
2767 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
2768 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
2769 	status = nfs_ok;
2770 
2771 out:
2772 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2773 	if (context)
2774 		security_release_secctx(context, contextlen);
2775 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2776 	kfree(acl);
2777 	if (tempfh) {
2778 		fh_put(tempfh);
2779 		kfree(tempfh);
2780 	}
2781 	if (status)
2782 		xdr_truncate_encode(xdr, starting_len);
2783 	return status;
2784 out_nfserr:
2785 	status = nfserrno(err);
2786 	goto out;
2787 out_resource:
2788 	status = nfserr_resource;
2789 	goto out;
2790 }
2791 
2792 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
2793 				struct xdr_buf *buf, __be32 *p, int bytes)
2794 {
2795 	xdr->scratch.iov_len = 0;
2796 	memset(buf, 0, sizeof(struct xdr_buf));
2797 	buf->head[0].iov_base = p;
2798 	buf->head[0].iov_len = 0;
2799 	buf->len = 0;
2800 	xdr->buf = buf;
2801 	xdr->iov = buf->head;
2802 	xdr->p = p;
2803 	xdr->end = (void *)p + bytes;
2804 	buf->buflen = bytes;
2805 }
2806 
2807 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
2808 			struct svc_fh *fhp, struct svc_export *exp,
2809 			struct dentry *dentry, u32 *bmval,
2810 			struct svc_rqst *rqstp, int ignore_crossmnt)
2811 {
2812 	struct xdr_buf dummy;
2813 	struct xdr_stream xdr;
2814 	__be32 ret;
2815 
2816 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
2817 	ret = nfsd4_encode_fattr(&xdr, fhp, exp, dentry, bmval, rqstp,
2818 							ignore_crossmnt);
2819 	*p = xdr.p;
2820 	return ret;
2821 }
2822 
2823 static inline int attributes_need_mount(u32 *bmval)
2824 {
2825 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2826 		return 1;
2827 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2828 		return 1;
2829 	return 0;
2830 }
2831 
2832 static __be32
2833 nfsd4_encode_dirent_fattr(struct xdr_stream *xdr, struct nfsd4_readdir *cd,
2834 			const char *name, int namlen)
2835 {
2836 	struct svc_export *exp = cd->rd_fhp->fh_export;
2837 	struct dentry *dentry;
2838 	__be32 nfserr;
2839 	int ignore_crossmnt = 0;
2840 
2841 	dentry = lookup_one_len(name, cd->rd_fhp->fh_dentry, namlen);
2842 	if (IS_ERR(dentry))
2843 		return nfserrno(PTR_ERR(dentry));
2844 	if (d_really_is_negative(dentry)) {
2845 		/*
2846 		 * nfsd_buffered_readdir drops the i_mutex between
2847 		 * readdir and calling this callback, leaving a window
2848 		 * where this directory entry could have gone away.
2849 		 */
2850 		dput(dentry);
2851 		return nfserr_noent;
2852 	}
2853 
2854 	exp_get(exp);
2855 	/*
2856 	 * In the case of a mountpoint, the client may be asking for
2857 	 * attributes that are only properties of the underlying filesystem
2858 	 * as opposed to the cross-mounted file system. In such a case,
2859 	 * we will not follow the cross mount and will fill the attribtutes
2860 	 * directly from the mountpoint dentry.
2861 	 */
2862 	if (nfsd_mountpoint(dentry, exp)) {
2863 		int err;
2864 
2865 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
2866 				&& !attributes_need_mount(cd->rd_bmval)) {
2867 			ignore_crossmnt = 1;
2868 			goto out_encode;
2869 		}
2870 		/*
2871 		 * Why the heck aren't we just using nfsd_lookup??
2872 		 * Different "."/".." handling?  Something else?
2873 		 * At least, add a comment here to explain....
2874 		 */
2875 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
2876 		if (err) {
2877 			nfserr = nfserrno(err);
2878 			goto out_put;
2879 		}
2880 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
2881 		if (nfserr)
2882 			goto out_put;
2883 
2884 	}
2885 out_encode:
2886 	nfserr = nfsd4_encode_fattr(xdr, NULL, exp, dentry, cd->rd_bmval,
2887 					cd->rd_rqstp, ignore_crossmnt);
2888 out_put:
2889 	dput(dentry);
2890 	exp_put(exp);
2891 	return nfserr;
2892 }
2893 
2894 static __be32 *
2895 nfsd4_encode_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
2896 {
2897 	__be32 *p;
2898 
2899 	p = xdr_reserve_space(xdr, 20);
2900 	if (!p)
2901 		return NULL;
2902 	*p++ = htonl(2);
2903 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
2904 	*p++ = htonl(0);			 /* bmval1 */
2905 
2906 	*p++ = htonl(4);     /* attribute length */
2907 	*p++ = nfserr;       /* no htonl */
2908 	return p;
2909 }
2910 
2911 static int
2912 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
2913 		    loff_t offset, u64 ino, unsigned int d_type)
2914 {
2915 	struct readdir_cd *ccd = ccdv;
2916 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
2917 	struct xdr_stream *xdr = cd->xdr;
2918 	int start_offset = xdr->buf->len;
2919 	int cookie_offset;
2920 	u32 name_and_cookie;
2921 	int entry_bytes;
2922 	__be32 nfserr = nfserr_toosmall;
2923 	__be64 wire_offset;
2924 	__be32 *p;
2925 
2926 	/* In nfsv4, "." and ".." never make it onto the wire.. */
2927 	if (name && isdotent(name, namlen)) {
2928 		cd->common.err = nfs_ok;
2929 		return 0;
2930 	}
2931 
2932 	if (cd->cookie_offset) {
2933 		wire_offset = cpu_to_be64(offset);
2934 		write_bytes_to_xdr_buf(xdr->buf, cd->cookie_offset,
2935 							&wire_offset, 8);
2936 	}
2937 
2938 	p = xdr_reserve_space(xdr, 4);
2939 	if (!p)
2940 		goto fail;
2941 	*p++ = xdr_one;                             /* mark entry present */
2942 	cookie_offset = xdr->buf->len;
2943 	p = xdr_reserve_space(xdr, 3*4 + namlen);
2944 	if (!p)
2945 		goto fail;
2946 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
2947 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
2948 
2949 	nfserr = nfsd4_encode_dirent_fattr(xdr, cd, name, namlen);
2950 	switch (nfserr) {
2951 	case nfs_ok:
2952 		break;
2953 	case nfserr_resource:
2954 		nfserr = nfserr_toosmall;
2955 		goto fail;
2956 	case nfserr_noent:
2957 		xdr_truncate_encode(xdr, start_offset);
2958 		goto skip_entry;
2959 	default:
2960 		/*
2961 		 * If the client requested the RDATTR_ERROR attribute,
2962 		 * we stuff the error code into this attribute
2963 		 * and continue.  If this attribute was not requested,
2964 		 * then in accordance with the spec, we fail the
2965 		 * entire READDIR operation(!)
2966 		 */
2967 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
2968 			goto fail;
2969 		p = nfsd4_encode_rdattr_error(xdr, nfserr);
2970 		if (p == NULL) {
2971 			nfserr = nfserr_toosmall;
2972 			goto fail;
2973 		}
2974 	}
2975 	nfserr = nfserr_toosmall;
2976 	entry_bytes = xdr->buf->len - start_offset;
2977 	if (entry_bytes > cd->rd_maxcount)
2978 		goto fail;
2979 	cd->rd_maxcount -= entry_bytes;
2980 	/*
2981 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so
2982 	 * let's always let through the first entry, at least:
2983 	 */
2984 	if (!cd->rd_dircount)
2985 		goto fail;
2986 	name_and_cookie = 4 + 4 * XDR_QUADLEN(namlen) + 8;
2987 	if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
2988 		goto fail;
2989 	cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
2990 
2991 	cd->cookie_offset = cookie_offset;
2992 skip_entry:
2993 	cd->common.err = nfs_ok;
2994 	return 0;
2995 fail:
2996 	xdr_truncate_encode(xdr, start_offset);
2997 	cd->common.err = nfserr;
2998 	return -EINVAL;
2999 }
3000 
3001 static __be32
3002 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
3003 {
3004 	__be32 *p;
3005 
3006 	p = xdr_reserve_space(xdr, sizeof(stateid_t));
3007 	if (!p)
3008 		return nfserr_resource;
3009 	*p++ = cpu_to_be32(sid->si_generation);
3010 	p = xdr_encode_opaque_fixed(p, &sid->si_opaque,
3011 					sizeof(stateid_opaque_t));
3012 	return 0;
3013 }
3014 
3015 static __be32
3016 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
3017 {
3018 	struct xdr_stream *xdr = &resp->xdr;
3019 	__be32 *p;
3020 
3021 	if (!nfserr) {
3022 		p = xdr_reserve_space(xdr, 8);
3023 		if (!p)
3024 			return nfserr_resource;
3025 		*p++ = cpu_to_be32(access->ac_supported);
3026 		*p++ = cpu_to_be32(access->ac_resp_access);
3027 	}
3028 	return nfserr;
3029 }
3030 
3031 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
3032 {
3033 	struct xdr_stream *xdr = &resp->xdr;
3034 	__be32 *p;
3035 
3036 	if (!nfserr) {
3037 		p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 8);
3038 		if (!p)
3039 			return nfserr_resource;
3040 		p = xdr_encode_opaque_fixed(p, bcts->sessionid.data,
3041 						NFS4_MAX_SESSIONID_LEN);
3042 		*p++ = cpu_to_be32(bcts->dir);
3043 		/* Sorry, we do not yet support RDMA over 4.1: */
3044 		*p++ = cpu_to_be32(0);
3045 	}
3046 	return nfserr;
3047 }
3048 
3049 static __be32
3050 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
3051 {
3052 	struct xdr_stream *xdr = &resp->xdr;
3053 
3054 	if (!nfserr)
3055 		nfserr = nfsd4_encode_stateid(xdr, &close->cl_stateid);
3056 
3057 	return nfserr;
3058 }
3059 
3060 
3061 static __be32
3062 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
3063 {
3064 	struct xdr_stream *xdr = &resp->xdr;
3065 	__be32 *p;
3066 
3067 	if (!nfserr) {
3068 		p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3069 		if (!p)
3070 			return nfserr_resource;
3071 		p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
3072 						NFS4_VERIFIER_SIZE);
3073 	}
3074 	return nfserr;
3075 }
3076 
3077 static __be32
3078 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
3079 {
3080 	struct xdr_stream *xdr = &resp->xdr;
3081 	__be32 *p;
3082 
3083 	if (!nfserr) {
3084 		p = xdr_reserve_space(xdr, 20);
3085 		if (!p)
3086 			return nfserr_resource;
3087 		encode_cinfo(p, &create->cr_cinfo);
3088 		nfserr = nfsd4_encode_bitmap(xdr, create->cr_bmval[0],
3089 				create->cr_bmval[1], create->cr_bmval[2]);
3090 	}
3091 	return nfserr;
3092 }
3093 
3094 static __be32
3095 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
3096 {
3097 	struct svc_fh *fhp = getattr->ga_fhp;
3098 	struct xdr_stream *xdr = &resp->xdr;
3099 
3100 	if (nfserr)
3101 		return nfserr;
3102 
3103 	nfserr = nfsd4_encode_fattr(xdr, fhp, fhp->fh_export, fhp->fh_dentry,
3104 				    getattr->ga_bmval,
3105 				    resp->rqstp, 0);
3106 	return nfserr;
3107 }
3108 
3109 static __be32
3110 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
3111 {
3112 	struct xdr_stream *xdr = &resp->xdr;
3113 	struct svc_fh *fhp = *fhpp;
3114 	unsigned int len;
3115 	__be32 *p;
3116 
3117 	if (!nfserr) {
3118 		len = fhp->fh_handle.fh_size;
3119 		p = xdr_reserve_space(xdr, len + 4);
3120 		if (!p)
3121 			return nfserr_resource;
3122 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base, len);
3123 	}
3124 	return nfserr;
3125 }
3126 
3127 /*
3128 * Including all fields other than the name, a LOCK4denied structure requires
3129 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
3130 */
3131 static __be32
3132 nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld)
3133 {
3134 	struct xdr_netobj *conf = &ld->ld_owner;
3135 	__be32 *p;
3136 
3137 again:
3138 	p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len));
3139 	if (!p) {
3140 		/*
3141 		 * Don't fail to return the result just because we can't
3142 		 * return the conflicting open:
3143 		 */
3144 		if (conf->len) {
3145 			kfree(conf->data);
3146 			conf->len = 0;
3147 			conf->data = NULL;
3148 			goto again;
3149 		}
3150 		return nfserr_resource;
3151 	}
3152 	p = xdr_encode_hyper(p, ld->ld_start);
3153 	p = xdr_encode_hyper(p, ld->ld_length);
3154 	*p++ = cpu_to_be32(ld->ld_type);
3155 	if (conf->len) {
3156 		p = xdr_encode_opaque_fixed(p, &ld->ld_clientid, 8);
3157 		p = xdr_encode_opaque(p, conf->data, conf->len);
3158 		kfree(conf->data);
3159 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
3160 		p = xdr_encode_hyper(p, (u64)0); /* clientid */
3161 		*p++ = cpu_to_be32(0); /* length of owner name */
3162 	}
3163 	return nfserr_denied;
3164 }
3165 
3166 static __be32
3167 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
3168 {
3169 	struct xdr_stream *xdr = &resp->xdr;
3170 
3171 	if (!nfserr)
3172 		nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid);
3173 	else if (nfserr == nfserr_denied)
3174 		nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied);
3175 
3176 	return nfserr;
3177 }
3178 
3179 static __be32
3180 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
3181 {
3182 	struct xdr_stream *xdr = &resp->xdr;
3183 
3184 	if (nfserr == nfserr_denied)
3185 		nfsd4_encode_lock_denied(xdr, &lockt->lt_denied);
3186 	return nfserr;
3187 }
3188 
3189 static __be32
3190 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
3191 {
3192 	struct xdr_stream *xdr = &resp->xdr;
3193 
3194 	if (!nfserr)
3195 		nfserr = nfsd4_encode_stateid(xdr, &locku->lu_stateid);
3196 
3197 	return nfserr;
3198 }
3199 
3200 
3201 static __be32
3202 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
3203 {
3204 	struct xdr_stream *xdr = &resp->xdr;
3205 	__be32 *p;
3206 
3207 	if (!nfserr) {
3208 		p = xdr_reserve_space(xdr, 20);
3209 		if (!p)
3210 			return nfserr_resource;
3211 		p = encode_cinfo(p, &link->li_cinfo);
3212 	}
3213 	return nfserr;
3214 }
3215 
3216 
3217 static __be32
3218 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
3219 {
3220 	struct xdr_stream *xdr = &resp->xdr;
3221 	__be32 *p;
3222 
3223 	if (nfserr)
3224 		goto out;
3225 
3226 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
3227 	if (nfserr)
3228 		goto out;
3229 	p = xdr_reserve_space(xdr, 24);
3230 	if (!p)
3231 		return nfserr_resource;
3232 	p = encode_cinfo(p, &open->op_cinfo);
3233 	*p++ = cpu_to_be32(open->op_rflags);
3234 
3235 	nfserr = nfsd4_encode_bitmap(xdr, open->op_bmval[0], open->op_bmval[1],
3236 					open->op_bmval[2]);
3237 	if (nfserr)
3238 		goto out;
3239 
3240 	p = xdr_reserve_space(xdr, 4);
3241 	if (!p)
3242 		return nfserr_resource;
3243 
3244 	*p++ = cpu_to_be32(open->op_delegate_type);
3245 	switch (open->op_delegate_type) {
3246 	case NFS4_OPEN_DELEGATE_NONE:
3247 		break;
3248 	case NFS4_OPEN_DELEGATE_READ:
3249 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3250 		if (nfserr)
3251 			return nfserr;
3252 		p = xdr_reserve_space(xdr, 20);
3253 		if (!p)
3254 			return nfserr_resource;
3255 		*p++ = cpu_to_be32(open->op_recall);
3256 
3257 		/*
3258 		 * TODO: ACE's in delegations
3259 		 */
3260 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3261 		*p++ = cpu_to_be32(0);
3262 		*p++ = cpu_to_be32(0);
3263 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3264 		break;
3265 	case NFS4_OPEN_DELEGATE_WRITE:
3266 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3267 		if (nfserr)
3268 			return nfserr;
3269 		p = xdr_reserve_space(xdr, 32);
3270 		if (!p)
3271 			return nfserr_resource;
3272 		*p++ = cpu_to_be32(0);
3273 
3274 		/*
3275 		 * TODO: space_limit's in delegations
3276 		 */
3277 		*p++ = cpu_to_be32(NFS4_LIMIT_SIZE);
3278 		*p++ = cpu_to_be32(~(u32)0);
3279 		*p++ = cpu_to_be32(~(u32)0);
3280 
3281 		/*
3282 		 * TODO: ACE's in delegations
3283 		 */
3284 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3285 		*p++ = cpu_to_be32(0);
3286 		*p++ = cpu_to_be32(0);
3287 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3288 		break;
3289 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
3290 		switch (open->op_why_no_deleg) {
3291 		case WND4_CONTENTION:
3292 		case WND4_RESOURCE:
3293 			p = xdr_reserve_space(xdr, 8);
3294 			if (!p)
3295 				return nfserr_resource;
3296 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3297 			/* deleg signaling not supported yet: */
3298 			*p++ = cpu_to_be32(0);
3299 			break;
3300 		default:
3301 			p = xdr_reserve_space(xdr, 4);
3302 			if (!p)
3303 				return nfserr_resource;
3304 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3305 		}
3306 		break;
3307 	default:
3308 		BUG();
3309 	}
3310 	/* XXX save filehandle here */
3311 out:
3312 	return nfserr;
3313 }
3314 
3315 static __be32
3316 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
3317 {
3318 	struct xdr_stream *xdr = &resp->xdr;
3319 
3320 	if (!nfserr)
3321 		nfserr = nfsd4_encode_stateid(xdr, &oc->oc_resp_stateid);
3322 
3323 	return nfserr;
3324 }
3325 
3326 static __be32
3327 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
3328 {
3329 	struct xdr_stream *xdr = &resp->xdr;
3330 
3331 	if (!nfserr)
3332 		nfserr = nfsd4_encode_stateid(xdr, &od->od_stateid);
3333 
3334 	return nfserr;
3335 }
3336 
3337 static __be32 nfsd4_encode_splice_read(
3338 				struct nfsd4_compoundres *resp,
3339 				struct nfsd4_read *read,
3340 				struct file *file, unsigned long maxcount)
3341 {
3342 	struct xdr_stream *xdr = &resp->xdr;
3343 	struct xdr_buf *buf = xdr->buf;
3344 	u32 eof;
3345 	int space_left;
3346 	__be32 nfserr;
3347 	__be32 *p = xdr->p - 2;
3348 
3349 	/* Make sure there will be room for padding if needed */
3350 	if (xdr->end - xdr->p < 1)
3351 		return nfserr_resource;
3352 
3353 	nfserr = nfsd_splice_read(read->rd_rqstp, file,
3354 				  read->rd_offset, &maxcount);
3355 	if (nfserr) {
3356 		/*
3357 		 * nfsd_splice_actor may have already messed with the
3358 		 * page length; reset it so as not to confuse
3359 		 * xdr_truncate_encode:
3360 		 */
3361 		buf->page_len = 0;
3362 		return nfserr;
3363 	}
3364 
3365 	eof = (read->rd_offset + maxcount >=
3366 	       d_inode(read->rd_fhp->fh_dentry)->i_size);
3367 
3368 	*(p++) = htonl(eof);
3369 	*(p++) = htonl(maxcount);
3370 
3371 	buf->page_len = maxcount;
3372 	buf->len += maxcount;
3373 	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
3374 							/ PAGE_SIZE;
3375 
3376 	/* Use rest of head for padding and remaining ops: */
3377 	buf->tail[0].iov_base = xdr->p;
3378 	buf->tail[0].iov_len = 0;
3379 	xdr->iov = buf->tail;
3380 	if (maxcount&3) {
3381 		int pad = 4 - (maxcount&3);
3382 
3383 		*(xdr->p++) = 0;
3384 
3385 		buf->tail[0].iov_base += maxcount&3;
3386 		buf->tail[0].iov_len = pad;
3387 		buf->len += pad;
3388 	}
3389 
3390 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
3391 				buf->buflen - buf->len);
3392 	buf->buflen = buf->len + space_left;
3393 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
3394 
3395 	return 0;
3396 }
3397 
3398 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
3399 				 struct nfsd4_read *read,
3400 				 struct file *file, unsigned long maxcount)
3401 {
3402 	struct xdr_stream *xdr = &resp->xdr;
3403 	u32 eof;
3404 	int v;
3405 	int starting_len = xdr->buf->len - 8;
3406 	long len;
3407 	int thislen;
3408 	__be32 nfserr;
3409 	__be32 tmp;
3410 	__be32 *p;
3411 	u32 zzz = 0;
3412 	int pad;
3413 
3414 	len = maxcount;
3415 	v = 0;
3416 
3417 	thislen = min_t(long, len, ((void *)xdr->end - (void *)xdr->p));
3418 	p = xdr_reserve_space(xdr, (thislen+3)&~3);
3419 	WARN_ON_ONCE(!p);
3420 	resp->rqstp->rq_vec[v].iov_base = p;
3421 	resp->rqstp->rq_vec[v].iov_len = thislen;
3422 	v++;
3423 	len -= thislen;
3424 
3425 	while (len) {
3426 		thislen = min_t(long, len, PAGE_SIZE);
3427 		p = xdr_reserve_space(xdr, (thislen+3)&~3);
3428 		WARN_ON_ONCE(!p);
3429 		resp->rqstp->rq_vec[v].iov_base = p;
3430 		resp->rqstp->rq_vec[v].iov_len = thislen;
3431 		v++;
3432 		len -= thislen;
3433 	}
3434 	read->rd_vlen = v;
3435 
3436 	nfserr = nfsd_readv(file, read->rd_offset, resp->rqstp->rq_vec,
3437 			read->rd_vlen, &maxcount);
3438 	if (nfserr)
3439 		return nfserr;
3440 	xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3));
3441 
3442 	eof = (read->rd_offset + maxcount >=
3443 	       d_inode(read->rd_fhp->fh_dentry)->i_size);
3444 
3445 	tmp = htonl(eof);
3446 	write_bytes_to_xdr_buf(xdr->buf, starting_len    , &tmp, 4);
3447 	tmp = htonl(maxcount);
3448 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
3449 
3450 	pad = (maxcount&3) ? 4 - (maxcount&3) : 0;
3451 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 8 + maxcount,
3452 								&zzz, pad);
3453 	return 0;
3454 
3455 }
3456 
3457 static __be32
3458 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
3459 		  struct nfsd4_read *read)
3460 {
3461 	unsigned long maxcount;
3462 	struct xdr_stream *xdr = &resp->xdr;
3463 	struct file *file = read->rd_filp;
3464 	int starting_len = xdr->buf->len;
3465 	struct raparms *ra = NULL;
3466 	__be32 *p;
3467 
3468 	if (nfserr)
3469 		goto out;
3470 
3471 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
3472 	if (!p) {
3473 		WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
3474 		nfserr = nfserr_resource;
3475 		goto out;
3476 	}
3477 	if (resp->xdr.buf->page_len &&
3478 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
3479 		WARN_ON_ONCE(1);
3480 		nfserr = nfserr_resource;
3481 		goto out;
3482 	}
3483 	xdr_commit_encode(xdr);
3484 
3485 	maxcount = svc_max_payload(resp->rqstp);
3486 	maxcount = min_t(unsigned long, maxcount,
3487 			 (xdr->buf->buflen - xdr->buf->len));
3488 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
3489 
3490 	if (read->rd_tmp_file)
3491 		ra = nfsd_init_raparms(file);
3492 
3493 	if (file->f_op->splice_read &&
3494 	    test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
3495 		nfserr = nfsd4_encode_splice_read(resp, read, file, maxcount);
3496 	else
3497 		nfserr = nfsd4_encode_readv(resp, read, file, maxcount);
3498 
3499 	if (ra)
3500 		nfsd_put_raparams(file, ra);
3501 
3502 	if (nfserr)
3503 		xdr_truncate_encode(xdr, starting_len);
3504 
3505 out:
3506 	if (file)
3507 		fput(file);
3508 	return nfserr;
3509 }
3510 
3511 static __be32
3512 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3513 {
3514 	int maxcount;
3515 	__be32 wire_count;
3516 	int zero = 0;
3517 	struct xdr_stream *xdr = &resp->xdr;
3518 	int length_offset = xdr->buf->len;
3519 	__be32 *p;
3520 
3521 	if (nfserr)
3522 		return nfserr;
3523 
3524 	p = xdr_reserve_space(xdr, 4);
3525 	if (!p)
3526 		return nfserr_resource;
3527 	maxcount = PAGE_SIZE;
3528 
3529 	p = xdr_reserve_space(xdr, maxcount);
3530 	if (!p)
3531 		return nfserr_resource;
3532 	/*
3533 	 * XXX: By default, the ->readlink() VFS op will truncate symlinks
3534 	 * if they would overflow the buffer.  Is this kosher in NFSv4?  If
3535 	 * not, one easy fix is: if ->readlink() precisely fills the buffer,
3536 	 * assume that truncation occurred, and return NFS4ERR_RESOURCE.
3537 	 */
3538 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
3539 						(char *)p, &maxcount);
3540 	if (nfserr == nfserr_isdir)
3541 		nfserr = nfserr_inval;
3542 	if (nfserr) {
3543 		xdr_truncate_encode(xdr, length_offset);
3544 		return nfserr;
3545 	}
3546 
3547 	wire_count = htonl(maxcount);
3548 	write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
3549 	xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
3550 	if (maxcount & 3)
3551 		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
3552 						&zero, 4 - (maxcount&3));
3553 	return 0;
3554 }
3555 
3556 static __be32
3557 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3558 {
3559 	int maxcount;
3560 	int bytes_left;
3561 	loff_t offset;
3562 	__be64 wire_offset;
3563 	struct xdr_stream *xdr = &resp->xdr;
3564 	int starting_len = xdr->buf->len;
3565 	__be32 *p;
3566 
3567 	if (nfserr)
3568 		return nfserr;
3569 
3570 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3571 	if (!p)
3572 		return nfserr_resource;
3573 
3574 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3575 	*p++ = cpu_to_be32(0);
3576 	*p++ = cpu_to_be32(0);
3577 	resp->xdr.buf->head[0].iov_len = ((char *)resp->xdr.p)
3578 				- (char *)resp->xdr.buf->head[0].iov_base;
3579 
3580 	/*
3581 	 * Number of bytes left for directory entries allowing for the
3582 	 * final 8 bytes of the readdir and a following failed op:
3583 	 */
3584 	bytes_left = xdr->buf->buflen - xdr->buf->len
3585 			- COMPOUND_ERR_SLACK_SPACE - 8;
3586 	if (bytes_left < 0) {
3587 		nfserr = nfserr_resource;
3588 		goto err_no_verf;
3589 	}
3590 	maxcount = min_t(u32, readdir->rd_maxcount, INT_MAX);
3591 	/*
3592 	 * Note the rfc defines rd_maxcount as the size of the
3593 	 * READDIR4resok structure, which includes the verifier above
3594 	 * and the 8 bytes encoded at the end of this function:
3595 	 */
3596 	if (maxcount < 16) {
3597 		nfserr = nfserr_toosmall;
3598 		goto err_no_verf;
3599 	}
3600 	maxcount = min_t(int, maxcount-16, bytes_left);
3601 
3602 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
3603 	if (!readdir->rd_dircount)
3604 		readdir->rd_dircount = INT_MAX;
3605 
3606 	readdir->xdr = xdr;
3607 	readdir->rd_maxcount = maxcount;
3608 	readdir->common.err = 0;
3609 	readdir->cookie_offset = 0;
3610 
3611 	offset = readdir->rd_cookie;
3612 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3613 			      &offset,
3614 			      &readdir->common, nfsd4_encode_dirent);
3615 	if (nfserr == nfs_ok &&
3616 	    readdir->common.err == nfserr_toosmall &&
3617 	    xdr->buf->len == starting_len + 8) {
3618 		/* nothing encoded; which limit did we hit?: */
3619 		if (maxcount - 16 < bytes_left)
3620 			/* It was the fault of rd_maxcount: */
3621 			nfserr = nfserr_toosmall;
3622 		else
3623 			/* We ran out of buffer space: */
3624 			nfserr = nfserr_resource;
3625 	}
3626 	if (nfserr)
3627 		goto err_no_verf;
3628 
3629 	if (readdir->cookie_offset) {
3630 		wire_offset = cpu_to_be64(offset);
3631 		write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset,
3632 							&wire_offset, 8);
3633 	}
3634 
3635 	p = xdr_reserve_space(xdr, 8);
3636 	if (!p) {
3637 		WARN_ON_ONCE(1);
3638 		goto err_no_verf;
3639 	}
3640 	*p++ = 0;	/* no more entries */
3641 	*p++ = htonl(readdir->common.err == nfserr_eof);
3642 
3643 	return 0;
3644 err_no_verf:
3645 	xdr_truncate_encode(xdr, starting_len);
3646 	return nfserr;
3647 }
3648 
3649 static __be32
3650 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3651 {
3652 	struct xdr_stream *xdr = &resp->xdr;
3653 	__be32 *p;
3654 
3655 	if (!nfserr) {
3656 		p = xdr_reserve_space(xdr, 20);
3657 		if (!p)
3658 			return nfserr_resource;
3659 		p = encode_cinfo(p, &remove->rm_cinfo);
3660 	}
3661 	return nfserr;
3662 }
3663 
3664 static __be32
3665 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3666 {
3667 	struct xdr_stream *xdr = &resp->xdr;
3668 	__be32 *p;
3669 
3670 	if (!nfserr) {
3671 		p = xdr_reserve_space(xdr, 40);
3672 		if (!p)
3673 			return nfserr_resource;
3674 		p = encode_cinfo(p, &rename->rn_sinfo);
3675 		p = encode_cinfo(p, &rename->rn_tinfo);
3676 	}
3677 	return nfserr;
3678 }
3679 
3680 static __be32
3681 nfsd4_do_encode_secinfo(struct xdr_stream *xdr,
3682 			 __be32 nfserr, struct svc_export *exp)
3683 {
3684 	u32 i, nflavs, supported;
3685 	struct exp_flavor_info *flavs;
3686 	struct exp_flavor_info def_flavs[2];
3687 	__be32 *p, *flavorsp;
3688 	static bool report = true;
3689 
3690 	if (nfserr)
3691 		goto out;
3692 	nfserr = nfserr_resource;
3693 	if (exp->ex_nflavors) {
3694 		flavs = exp->ex_flavors;
3695 		nflavs = exp->ex_nflavors;
3696 	} else { /* Handling of some defaults in absence of real secinfo: */
3697 		flavs = def_flavs;
3698 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3699 			nflavs = 2;
3700 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3701 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3702 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3703 			nflavs = 1;
3704 			flavs[0].pseudoflavor
3705 					= svcauth_gss_flavor(exp->ex_client);
3706 		} else {
3707 			nflavs = 1;
3708 			flavs[0].pseudoflavor
3709 					= exp->ex_client->flavour->flavour;
3710 		}
3711 	}
3712 
3713 	supported = 0;
3714 	p = xdr_reserve_space(xdr, 4);
3715 	if (!p)
3716 		goto out;
3717 	flavorsp = p++;		/* to be backfilled later */
3718 
3719 	for (i = 0; i < nflavs; i++) {
3720 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
3721 		struct rpcsec_gss_info info;
3722 
3723 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
3724 			supported++;
3725 			p = xdr_reserve_space(xdr, 4 + 4 +
3726 					      XDR_LEN(info.oid.len) + 4 + 4);
3727 			if (!p)
3728 				goto out;
3729 			*p++ = cpu_to_be32(RPC_AUTH_GSS);
3730 			p = xdr_encode_opaque(p,  info.oid.data, info.oid.len);
3731 			*p++ = cpu_to_be32(info.qop);
3732 			*p++ = cpu_to_be32(info.service);
3733 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
3734 			supported++;
3735 			p = xdr_reserve_space(xdr, 4);
3736 			if (!p)
3737 				goto out;
3738 			*p++ = cpu_to_be32(pf);
3739 		} else {
3740 			if (report)
3741 				pr_warn("NFS: SECINFO: security flavor %u "
3742 					"is not supported\n", pf);
3743 		}
3744 	}
3745 
3746 	if (nflavs != supported)
3747 		report = false;
3748 	*flavorsp = htonl(supported);
3749 	nfserr = 0;
3750 out:
3751 	if (exp)
3752 		exp_put(exp);
3753 	return nfserr;
3754 }
3755 
3756 static __be32
3757 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3758 		     struct nfsd4_secinfo *secinfo)
3759 {
3760 	struct xdr_stream *xdr = &resp->xdr;
3761 
3762 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->si_exp);
3763 }
3764 
3765 static __be32
3766 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3767 		     struct nfsd4_secinfo_no_name *secinfo)
3768 {
3769 	struct xdr_stream *xdr = &resp->xdr;
3770 
3771 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->sin_exp);
3772 }
3773 
3774 /*
3775  * The SETATTR encode routine is special -- it always encodes a bitmap,
3776  * regardless of the error status.
3777  */
3778 static __be32
3779 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3780 {
3781 	struct xdr_stream *xdr = &resp->xdr;
3782 	__be32 *p;
3783 
3784 	p = xdr_reserve_space(xdr, 16);
3785 	if (!p)
3786 		return nfserr_resource;
3787 	if (nfserr) {
3788 		*p++ = cpu_to_be32(3);
3789 		*p++ = cpu_to_be32(0);
3790 		*p++ = cpu_to_be32(0);
3791 		*p++ = cpu_to_be32(0);
3792 	}
3793 	else {
3794 		*p++ = cpu_to_be32(3);
3795 		*p++ = cpu_to_be32(setattr->sa_bmval[0]);
3796 		*p++ = cpu_to_be32(setattr->sa_bmval[1]);
3797 		*p++ = cpu_to_be32(setattr->sa_bmval[2]);
3798 	}
3799 	return nfserr;
3800 }
3801 
3802 static __be32
3803 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3804 {
3805 	struct xdr_stream *xdr = &resp->xdr;
3806 	__be32 *p;
3807 
3808 	if (!nfserr) {
3809 		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
3810 		if (!p)
3811 			return nfserr_resource;
3812 		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
3813 		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
3814 						NFS4_VERIFIER_SIZE);
3815 	}
3816 	else if (nfserr == nfserr_clid_inuse) {
3817 		p = xdr_reserve_space(xdr, 8);
3818 		if (!p)
3819 			return nfserr_resource;
3820 		*p++ = cpu_to_be32(0);
3821 		*p++ = cpu_to_be32(0);
3822 	}
3823 	return nfserr;
3824 }
3825 
3826 static __be32
3827 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3828 {
3829 	struct xdr_stream *xdr = &resp->xdr;
3830 	__be32 *p;
3831 
3832 	if (!nfserr) {
3833 		p = xdr_reserve_space(xdr, 16);
3834 		if (!p)
3835 			return nfserr_resource;
3836 		*p++ = cpu_to_be32(write->wr_bytes_written);
3837 		*p++ = cpu_to_be32(write->wr_how_written);
3838 		p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
3839 							NFS4_VERIFIER_SIZE);
3840 	}
3841 	return nfserr;
3842 }
3843 
3844 static const u32 nfs4_minimal_spo_must_enforce[2] = {
3845 	[1] = 1 << (OP_BIND_CONN_TO_SESSION - 32) |
3846 	      1 << (OP_EXCHANGE_ID - 32) |
3847 	      1 << (OP_CREATE_SESSION - 32) |
3848 	      1 << (OP_DESTROY_SESSION - 32) |
3849 	      1 << (OP_DESTROY_CLIENTID - 32)
3850 };
3851 
3852 static __be32
3853 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
3854 			 struct nfsd4_exchange_id *exid)
3855 {
3856 	struct xdr_stream *xdr = &resp->xdr;
3857 	__be32 *p;
3858 	char *major_id;
3859 	char *server_scope;
3860 	int major_id_sz;
3861 	int server_scope_sz;
3862 	uint64_t minor_id = 0;
3863 
3864 	if (nfserr)
3865 		return nfserr;
3866 
3867 	major_id = utsname()->nodename;
3868 	major_id_sz = strlen(major_id);
3869 	server_scope = utsname()->nodename;
3870 	server_scope_sz = strlen(server_scope);
3871 
3872 	p = xdr_reserve_space(xdr,
3873 		8 /* eir_clientid */ +
3874 		4 /* eir_sequenceid */ +
3875 		4 /* eir_flags */ +
3876 		4 /* spr_how */);
3877 	if (!p)
3878 		return nfserr_resource;
3879 
3880 	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
3881 	*p++ = cpu_to_be32(exid->seqid);
3882 	*p++ = cpu_to_be32(exid->flags);
3883 
3884 	*p++ = cpu_to_be32(exid->spa_how);
3885 
3886 	switch (exid->spa_how) {
3887 	case SP4_NONE:
3888 		break;
3889 	case SP4_MACH_CRED:
3890 		/* spo_must_enforce, spo_must_allow */
3891 		p = xdr_reserve_space(xdr, 16);
3892 		if (!p)
3893 			return nfserr_resource;
3894 
3895 		/* spo_must_enforce bitmap: */
3896 		*p++ = cpu_to_be32(2);
3897 		*p++ = cpu_to_be32(nfs4_minimal_spo_must_enforce[0]);
3898 		*p++ = cpu_to_be32(nfs4_minimal_spo_must_enforce[1]);
3899 		/* empty spo_must_allow bitmap: */
3900 		*p++ = cpu_to_be32(0);
3901 
3902 		break;
3903 	default:
3904 		WARN_ON_ONCE(1);
3905 	}
3906 
3907 	p = xdr_reserve_space(xdr,
3908 		8 /* so_minor_id */ +
3909 		4 /* so_major_id.len */ +
3910 		(XDR_QUADLEN(major_id_sz) * 4) +
3911 		4 /* eir_server_scope.len */ +
3912 		(XDR_QUADLEN(server_scope_sz) * 4) +
3913 		4 /* eir_server_impl_id.count (0) */);
3914 	if (!p)
3915 		return nfserr_resource;
3916 
3917 	/* The server_owner struct */
3918 	p = xdr_encode_hyper(p, minor_id);      /* Minor id */
3919 	/* major id */
3920 	p = xdr_encode_opaque(p, major_id, major_id_sz);
3921 
3922 	/* Server scope */
3923 	p = xdr_encode_opaque(p, server_scope, server_scope_sz);
3924 
3925 	/* Implementation id */
3926 	*p++ = cpu_to_be32(0);	/* zero length nfs_impl_id4 array */
3927 	return 0;
3928 }
3929 
3930 static __be32
3931 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
3932 			    struct nfsd4_create_session *sess)
3933 {
3934 	struct xdr_stream *xdr = &resp->xdr;
3935 	__be32 *p;
3936 
3937 	if (nfserr)
3938 		return nfserr;
3939 
3940 	p = xdr_reserve_space(xdr, 24);
3941 	if (!p)
3942 		return nfserr_resource;
3943 	p = xdr_encode_opaque_fixed(p, sess->sessionid.data,
3944 					NFS4_MAX_SESSIONID_LEN);
3945 	*p++ = cpu_to_be32(sess->seqid);
3946 	*p++ = cpu_to_be32(sess->flags);
3947 
3948 	p = xdr_reserve_space(xdr, 28);
3949 	if (!p)
3950 		return nfserr_resource;
3951 	*p++ = cpu_to_be32(0); /* headerpadsz */
3952 	*p++ = cpu_to_be32(sess->fore_channel.maxreq_sz);
3953 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_sz);
3954 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_cached);
3955 	*p++ = cpu_to_be32(sess->fore_channel.maxops);
3956 	*p++ = cpu_to_be32(sess->fore_channel.maxreqs);
3957 	*p++ = cpu_to_be32(sess->fore_channel.nr_rdma_attrs);
3958 
3959 	if (sess->fore_channel.nr_rdma_attrs) {
3960 		p = xdr_reserve_space(xdr, 4);
3961 		if (!p)
3962 			return nfserr_resource;
3963 		*p++ = cpu_to_be32(sess->fore_channel.rdma_attrs);
3964 	}
3965 
3966 	p = xdr_reserve_space(xdr, 28);
3967 	if (!p)
3968 		return nfserr_resource;
3969 	*p++ = cpu_to_be32(0); /* headerpadsz */
3970 	*p++ = cpu_to_be32(sess->back_channel.maxreq_sz);
3971 	*p++ = cpu_to_be32(sess->back_channel.maxresp_sz);
3972 	*p++ = cpu_to_be32(sess->back_channel.maxresp_cached);
3973 	*p++ = cpu_to_be32(sess->back_channel.maxops);
3974 	*p++ = cpu_to_be32(sess->back_channel.maxreqs);
3975 	*p++ = cpu_to_be32(sess->back_channel.nr_rdma_attrs);
3976 
3977 	if (sess->back_channel.nr_rdma_attrs) {
3978 		p = xdr_reserve_space(xdr, 4);
3979 		if (!p)
3980 			return nfserr_resource;
3981 		*p++ = cpu_to_be32(sess->back_channel.rdma_attrs);
3982 	}
3983 	return 0;
3984 }
3985 
3986 static __be32
3987 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
3988 		      struct nfsd4_sequence *seq)
3989 {
3990 	struct xdr_stream *xdr = &resp->xdr;
3991 	__be32 *p;
3992 
3993 	if (nfserr)
3994 		return nfserr;
3995 
3996 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 20);
3997 	if (!p)
3998 		return nfserr_resource;
3999 	p = xdr_encode_opaque_fixed(p, seq->sessionid.data,
4000 					NFS4_MAX_SESSIONID_LEN);
4001 	*p++ = cpu_to_be32(seq->seqid);
4002 	*p++ = cpu_to_be32(seq->slotid);
4003 	/* Note slotid's are numbered from zero: */
4004 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_highest_slotid */
4005 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_target_highest_slotid */
4006 	*p++ = cpu_to_be32(seq->status_flags);
4007 
4008 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
4009 	return 0;
4010 }
4011 
4012 static __be32
4013 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
4014 			  struct nfsd4_test_stateid *test_stateid)
4015 {
4016 	struct xdr_stream *xdr = &resp->xdr;
4017 	struct nfsd4_test_stateid_id *stateid, *next;
4018 	__be32 *p;
4019 
4020 	if (nfserr)
4021 		return nfserr;
4022 
4023 	p = xdr_reserve_space(xdr, 4 + (4 * test_stateid->ts_num_ids));
4024 	if (!p)
4025 		return nfserr_resource;
4026 	*p++ = htonl(test_stateid->ts_num_ids);
4027 
4028 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
4029 		*p++ = stateid->ts_id_status;
4030 	}
4031 
4032 	return nfserr;
4033 }
4034 
4035 #ifdef CONFIG_NFSD_PNFS
4036 static __be32
4037 nfsd4_encode_getdeviceinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
4038 		struct nfsd4_getdeviceinfo *gdev)
4039 {
4040 	struct xdr_stream *xdr = &resp->xdr;
4041 	const struct nfsd4_layout_ops *ops =
4042 		nfsd4_layout_ops[gdev->gd_layout_type];
4043 	u32 starting_len = xdr->buf->len, needed_len;
4044 	__be32 *p;
4045 
4046 	dprintk("%s: err %d\n", __func__, nfserr);
4047 	if (nfserr)
4048 		goto out;
4049 
4050 	nfserr = nfserr_resource;
4051 	p = xdr_reserve_space(xdr, 4);
4052 	if (!p)
4053 		goto out;
4054 
4055 	*p++ = cpu_to_be32(gdev->gd_layout_type);
4056 
4057 	/* If maxcount is 0 then just update notifications */
4058 	if (gdev->gd_maxcount != 0) {
4059 		nfserr = ops->encode_getdeviceinfo(xdr, gdev);
4060 		if (nfserr) {
4061 			/*
4062 			 * We don't bother to burden the layout drivers with
4063 			 * enforcing gd_maxcount, just tell the client to
4064 			 * come back with a bigger buffer if it's not enough.
4065 			 */
4066 			if (xdr->buf->len + 4 > gdev->gd_maxcount)
4067 				goto toosmall;
4068 			goto out;
4069 		}
4070 	}
4071 
4072 	nfserr = nfserr_resource;
4073 	if (gdev->gd_notify_types) {
4074 		p = xdr_reserve_space(xdr, 4 + 4);
4075 		if (!p)
4076 			goto out;
4077 		*p++ = cpu_to_be32(1);			/* bitmap length */
4078 		*p++ = cpu_to_be32(gdev->gd_notify_types);
4079 	} else {
4080 		p = xdr_reserve_space(xdr, 4);
4081 		if (!p)
4082 			goto out;
4083 		*p++ = 0;
4084 	}
4085 
4086 	nfserr = 0;
4087 out:
4088 	kfree(gdev->gd_device);
4089 	dprintk("%s: done: %d\n", __func__, be32_to_cpu(nfserr));
4090 	return nfserr;
4091 
4092 toosmall:
4093 	dprintk("%s: maxcount too small\n", __func__);
4094 	needed_len = xdr->buf->len + 4 /* notifications */;
4095 	xdr_truncate_encode(xdr, starting_len);
4096 	p = xdr_reserve_space(xdr, 4);
4097 	if (!p) {
4098 		nfserr = nfserr_resource;
4099 	} else {
4100 		*p++ = cpu_to_be32(needed_len);
4101 		nfserr = nfserr_toosmall;
4102 	}
4103 	goto out;
4104 }
4105 
4106 static __be32
4107 nfsd4_encode_layoutget(struct nfsd4_compoundres *resp, __be32 nfserr,
4108 		struct nfsd4_layoutget *lgp)
4109 {
4110 	struct xdr_stream *xdr = &resp->xdr;
4111 	const struct nfsd4_layout_ops *ops =
4112 		nfsd4_layout_ops[lgp->lg_layout_type];
4113 	__be32 *p;
4114 
4115 	dprintk("%s: err %d\n", __func__, nfserr);
4116 	if (nfserr)
4117 		goto out;
4118 
4119 	nfserr = nfserr_resource;
4120 	p = xdr_reserve_space(xdr, 36 + sizeof(stateid_opaque_t));
4121 	if (!p)
4122 		goto out;
4123 
4124 	*p++ = cpu_to_be32(1);	/* we always set return-on-close */
4125 	*p++ = cpu_to_be32(lgp->lg_sid.si_generation);
4126 	p = xdr_encode_opaque_fixed(p, &lgp->lg_sid.si_opaque,
4127 				    sizeof(stateid_opaque_t));
4128 
4129 	*p++ = cpu_to_be32(1);	/* we always return a single layout */
4130 	p = xdr_encode_hyper(p, lgp->lg_seg.offset);
4131 	p = xdr_encode_hyper(p, lgp->lg_seg.length);
4132 	*p++ = cpu_to_be32(lgp->lg_seg.iomode);
4133 	*p++ = cpu_to_be32(lgp->lg_layout_type);
4134 
4135 	nfserr = ops->encode_layoutget(xdr, lgp);
4136 out:
4137 	kfree(lgp->lg_content);
4138 	return nfserr;
4139 }
4140 
4141 static __be32
4142 nfsd4_encode_layoutcommit(struct nfsd4_compoundres *resp, __be32 nfserr,
4143 			  struct nfsd4_layoutcommit *lcp)
4144 {
4145 	struct xdr_stream *xdr = &resp->xdr;
4146 	__be32 *p;
4147 
4148 	if (nfserr)
4149 		return nfserr;
4150 
4151 	p = xdr_reserve_space(xdr, 4);
4152 	if (!p)
4153 		return nfserr_resource;
4154 	*p++ = cpu_to_be32(lcp->lc_size_chg);
4155 	if (lcp->lc_size_chg) {
4156 		p = xdr_reserve_space(xdr, 8);
4157 		if (!p)
4158 			return nfserr_resource;
4159 		p = xdr_encode_hyper(p, lcp->lc_newsize);
4160 	}
4161 
4162 	return nfs_ok;
4163 }
4164 
4165 static __be32
4166 nfsd4_encode_layoutreturn(struct nfsd4_compoundres *resp, __be32 nfserr,
4167 		struct nfsd4_layoutreturn *lrp)
4168 {
4169 	struct xdr_stream *xdr = &resp->xdr;
4170 	__be32 *p;
4171 
4172 	if (nfserr)
4173 		return nfserr;
4174 
4175 	p = xdr_reserve_space(xdr, 4);
4176 	if (!p)
4177 		return nfserr_resource;
4178 	*p++ = cpu_to_be32(lrp->lrs_present);
4179 	if (lrp->lrs_present)
4180 		return nfsd4_encode_stateid(xdr, &lrp->lr_sid);
4181 	return nfs_ok;
4182 }
4183 #endif /* CONFIG_NFSD_PNFS */
4184 
4185 static __be32
4186 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
4187 		  struct nfsd4_seek *seek)
4188 {
4189 	__be32 *p;
4190 
4191 	if (nfserr)
4192 		return nfserr;
4193 
4194 	p = xdr_reserve_space(&resp->xdr, 4 + 8);
4195 	*p++ = cpu_to_be32(seek->seek_eof);
4196 	p = xdr_encode_hyper(p, seek->seek_pos);
4197 
4198 	return nfserr;
4199 }
4200 
4201 static __be32
4202 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
4203 {
4204 	return nfserr;
4205 }
4206 
4207 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
4208 
4209 /*
4210  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
4211  * since we don't need to filter out obsolete ops as this is
4212  * done in the decoding phase.
4213  */
4214 static nfsd4_enc nfsd4_enc_ops[] = {
4215 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
4216 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
4217 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
4218 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
4219 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
4220 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4221 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
4222 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
4223 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
4224 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
4225 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
4226 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
4227 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
4228 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
4229 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4230 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
4231 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
4232 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
4233 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
4234 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4235 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
4236 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
4237 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
4238 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
4239 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
4240 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
4241 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
4242 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
4243 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
4244 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
4245 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
4246 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
4247 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
4248 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
4249 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
4250 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
4251 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
4252 
4253 	/* NFSv4.1 operations */
4254 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
4255 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
4256 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
4257 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
4258 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
4259 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
4260 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4261 #ifdef CONFIG_NFSD_PNFS
4262 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_getdeviceinfo,
4263 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4264 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_layoutcommit,
4265 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_layoutget,
4266 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_layoutreturn,
4267 #else
4268 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
4269 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
4270 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
4271 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
4272 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
4273 #endif
4274 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
4275 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
4276 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
4277 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
4278 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
4279 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
4280 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
4281 
4282 	/* NFSv4.2 operations */
4283 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4284 	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_noop,
4285 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
4286 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
4287 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
4288 	[OP_LAYOUTERROR]	= (nfsd4_enc)nfsd4_encode_noop,
4289 	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,
4290 	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,
4291 	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_noop,
4292 	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_noop,
4293 	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,
4294 	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,
4295 };
4296 
4297 /*
4298  * Calculate whether we still have space to encode repsize bytes.
4299  * There are two considerations:
4300  *     - For NFS versions >=4.1, the size of the reply must stay within
4301  *       session limits
4302  *     - For all NFS versions, we must stay within limited preallocated
4303  *       buffer space.
4304  *
4305  * This is called before the operation is processed, so can only provide
4306  * an upper estimate.  For some nonidempotent operations (such as
4307  * getattr), it's not necessarily a problem if that estimate is wrong,
4308  * as we can fail it after processing without significant side effects.
4309  */
4310 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
4311 {
4312 	struct xdr_buf *buf = &resp->rqstp->rq_res;
4313 	struct nfsd4_slot *slot = resp->cstate.slot;
4314 
4315 	if (buf->len + respsize <= buf->buflen)
4316 		return nfs_ok;
4317 	if (!nfsd4_has_session(&resp->cstate))
4318 		return nfserr_resource;
4319 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
4320 		WARN_ON_ONCE(1);
4321 		return nfserr_rep_too_big_to_cache;
4322 	}
4323 	return nfserr_rep_too_big;
4324 }
4325 
4326 void
4327 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
4328 {
4329 	struct xdr_stream *xdr = &resp->xdr;
4330 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
4331 	struct svc_rqst *rqstp = resp->rqstp;
4332 	int post_err_offset;
4333 	nfsd4_enc encoder;
4334 	__be32 *p;
4335 
4336 	p = xdr_reserve_space(xdr, 8);
4337 	if (!p) {
4338 		WARN_ON_ONCE(1);
4339 		return;
4340 	}
4341 	*p++ = cpu_to_be32(op->opnum);
4342 	post_err_offset = xdr->buf->len;
4343 
4344 	if (op->opnum == OP_ILLEGAL)
4345 		goto status;
4346 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
4347 	       !nfsd4_enc_ops[op->opnum]);
4348 	encoder = nfsd4_enc_ops[op->opnum];
4349 	op->status = encoder(resp, op->status, &op->u);
4350 	xdr_commit_encode(xdr);
4351 
4352 	/* nfsd4_check_resp_size guarantees enough room for error status */
4353 	if (!op->status) {
4354 		int space_needed = 0;
4355 		if (!nfsd4_last_compound_op(rqstp))
4356 			space_needed = COMPOUND_ERR_SLACK_SPACE;
4357 		op->status = nfsd4_check_resp_size(resp, space_needed);
4358 	}
4359 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
4360 		struct nfsd4_slot *slot = resp->cstate.slot;
4361 
4362 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
4363 			op->status = nfserr_rep_too_big_to_cache;
4364 		else
4365 			op->status = nfserr_rep_too_big;
4366 	}
4367 	if (op->status == nfserr_resource ||
4368 	    op->status == nfserr_rep_too_big ||
4369 	    op->status == nfserr_rep_too_big_to_cache) {
4370 		/*
4371 		 * The operation may have already been encoded or
4372 		 * partially encoded.  No op returns anything additional
4373 		 * in the case of one of these three errors, so we can
4374 		 * just truncate back to after the status.  But it's a
4375 		 * bug if we had to do this on a non-idempotent op:
4376 		 */
4377 		warn_on_nonidempotent_op(op);
4378 		xdr_truncate_encode(xdr, post_err_offset);
4379 	}
4380 	if (so) {
4381 		int len = xdr->buf->len - post_err_offset;
4382 
4383 		so->so_replay.rp_status = op->status;
4384 		so->so_replay.rp_buflen = len;
4385 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
4386 						so->so_replay.rp_buf, len);
4387 	}
4388 status:
4389 	/* Note that op->status is already in network byte order: */
4390 	write_bytes_to_xdr_buf(xdr->buf, post_err_offset - 4, &op->status, 4);
4391 }
4392 
4393 /*
4394  * Encode the reply stored in the stateowner reply cache
4395  *
4396  * XDR note: do not encode rp->rp_buflen: the buffer contains the
4397  * previously sent already encoded operation.
4398  */
4399 void
4400 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
4401 {
4402 	__be32 *p;
4403 	struct nfs4_replay *rp = op->replay;
4404 
4405 	BUG_ON(!rp);
4406 
4407 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
4408 	if (!p) {
4409 		WARN_ON_ONCE(1);
4410 		return;
4411 	}
4412 	*p++ = cpu_to_be32(op->opnum);
4413 	*p++ = rp->rp_status;  /* already xdr'ed */
4414 
4415 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
4416 }
4417 
4418 int
4419 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
4420 {
4421         return xdr_ressize_check(rqstp, p);
4422 }
4423 
4424 int nfsd4_release_compoundargs(void *rq, __be32 *p, void *resp)
4425 {
4426 	struct svc_rqst *rqstp = rq;
4427 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4428 
4429 	if (args->ops != args->iops) {
4430 		kfree(args->ops);
4431 		args->ops = args->iops;
4432 	}
4433 	kfree(args->tmpp);
4434 	args->tmpp = NULL;
4435 	while (args->to_free) {
4436 		struct svcxdr_tmpbuf *tb = args->to_free;
4437 		args->to_free = tb->next;
4438 		kfree(tb);
4439 	}
4440 	return 1;
4441 }
4442 
4443 int
4444 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundargs *args)
4445 {
4446 	if (rqstp->rq_arg.head[0].iov_len % 4) {
4447 		/* client is nuts */
4448 		dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)",
4449 			__func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid));
4450 		return 0;
4451 	}
4452 	args->p = p;
4453 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
4454 	args->pagelist = rqstp->rq_arg.pages;
4455 	args->pagelen = rqstp->rq_arg.page_len;
4456 	args->tmpp = NULL;
4457 	args->to_free = NULL;
4458 	args->ops = args->iops;
4459 	args->rqstp = rqstp;
4460 
4461 	return !nfsd4_decode_compound(args);
4462 }
4463 
4464 int
4465 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundres *resp)
4466 {
4467 	/*
4468 	 * All that remains is to write the tag and operation count...
4469 	 */
4470 	struct xdr_buf *buf = resp->xdr.buf;
4471 
4472 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
4473 				 buf->tail[0].iov_len);
4474 
4475 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
4476 
4477 	p = resp->tagp;
4478 	*p++ = htonl(resp->taglen);
4479 	memcpy(p, resp->tag, resp->taglen);
4480 	p += XDR_QUADLEN(resp->taglen);
4481 	*p++ = htonl(resp->opcnt);
4482 
4483 	nfsd4_sequence_done(resp);
4484 	return 1;
4485 }
4486 
4487 /*
4488  * Local variables:
4489  *  c-basic-offset: 8
4490  * End:
4491  */
4492