xref: /linux/fs/nfsd/nfs4xdr.c (revision 4949009eb8d40a441dcddcd96e101e77d31cf1b2)
1 /*
2  *  Server-side XDR for NFSv4
3  *
4  *  Copyright (c) 2002 The Regents of the University of Michigan.
5  *  All rights reserved.
6  *
7  *  Kendrick Smith <kmsmith@umich.edu>
8  *  Andy Adamson   <andros@umich.edu>
9  *
10  *  Redistribution and use in source and binary forms, with or without
11  *  modification, are permitted provided that the following conditions
12  *  are met:
13  *
14  *  1. Redistributions of source code must retain the above copyright
15  *     notice, this list of conditions and the following disclaimer.
16  *  2. Redistributions in binary form must reproduce the above copyright
17  *     notice, this list of conditions and the following disclaimer in the
18  *     documentation and/or other materials provided with the distribution.
19  *  3. Neither the name of the University nor the names of its
20  *     contributors may be used to endorse or promote products derived
21  *     from this software without specific prior written permission.
22  *
23  *  THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
24  *  WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
25  *  MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
26  *  DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
27  *  FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
28  *  CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
29  *  SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
30  *  BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
31  *  LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
32  *  NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
33  *  SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
34  */
35 
36 #include <linux/slab.h>
37 #include <linux/namei.h>
38 #include <linux/statfs.h>
39 #include <linux/utsname.h>
40 #include <linux/pagemap.h>
41 #include <linux/sunrpc/svcauth_gss.h>
42 
43 #include "idmap.h"
44 #include "acl.h"
45 #include "xdr4.h"
46 #include "vfs.h"
47 #include "state.h"
48 #include "cache.h"
49 #include "netns.h"
50 
51 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
52 #include <linux/security.h>
53 #endif
54 
55 
56 #define NFSDDBG_FACILITY		NFSDDBG_XDR
57 
58 /*
59  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
60  * directory in order to indicate to the client that a filesystem boundary is present
61  * We use a fixed fsid for a referral
62  */
63 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
64 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
65 
66 static __be32
67 check_filename(char *str, int len)
68 {
69 	int i;
70 
71 	if (len == 0)
72 		return nfserr_inval;
73 	if (isdotent(str, len))
74 		return nfserr_badname;
75 	for (i = 0; i < len; i++)
76 		if (str[i] == '/')
77 			return nfserr_badname;
78 	return 0;
79 }
80 
81 #define DECODE_HEAD				\
82 	__be32 *p;				\
83 	__be32 status
84 #define DECODE_TAIL				\
85 	status = 0;				\
86 out:						\
87 	return status;				\
88 xdr_error:					\
89 	dprintk("NFSD: xdr error (%s:%d)\n",	\
90 			__FILE__, __LINE__);	\
91 	status = nfserr_bad_xdr;		\
92 	goto out
93 
94 #define READMEM(x,nbytes) do {			\
95 	x = (char *)p;				\
96 	p += XDR_QUADLEN(nbytes);		\
97 } while (0)
98 #define SAVEMEM(x,nbytes) do {			\
99 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
100  		savemem(argp, p, nbytes) :	\
101  		(char *)p)) {			\
102 		dprintk("NFSD: xdr error (%s:%d)\n", \
103 				__FILE__, __LINE__); \
104 		goto xdr_error;			\
105 		}				\
106 	p += XDR_QUADLEN(nbytes);		\
107 } while (0)
108 #define COPYMEM(x,nbytes) do {			\
109 	memcpy((x), p, nbytes);			\
110 	p += XDR_QUADLEN(nbytes);		\
111 } while (0)
112 
113 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
114 #define READ_BUF(nbytes)  do {			\
115 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
116 		p = argp->p;			\
117 		argp->p += XDR_QUADLEN(nbytes);	\
118 	} else if (!(p = read_buf(argp, nbytes))) { \
119 		dprintk("NFSD: xdr error (%s:%d)\n", \
120 				__FILE__, __LINE__); \
121 		goto xdr_error;			\
122 	}					\
123 } while (0)
124 
125 static void next_decode_page(struct nfsd4_compoundargs *argp)
126 {
127 	argp->p = page_address(argp->pagelist[0]);
128 	argp->pagelist++;
129 	if (argp->pagelen < PAGE_SIZE) {
130 		argp->end = argp->p + (argp->pagelen>>2);
131 		argp->pagelen = 0;
132 	} else {
133 		argp->end = argp->p + (PAGE_SIZE>>2);
134 		argp->pagelen -= PAGE_SIZE;
135 	}
136 }
137 
138 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
139 {
140 	/* We want more bytes than seem to be available.
141 	 * Maybe we need a new page, maybe we have just run out
142 	 */
143 	unsigned int avail = (char *)argp->end - (char *)argp->p;
144 	__be32 *p;
145 	if (avail + argp->pagelen < nbytes)
146 		return NULL;
147 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
148 		return NULL;
149 	/* ok, we can do it with the current plus the next page */
150 	if (nbytes <= sizeof(argp->tmp))
151 		p = argp->tmp;
152 	else {
153 		kfree(argp->tmpp);
154 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
155 		if (!p)
156 			return NULL;
157 
158 	}
159 	/*
160 	 * The following memcpy is safe because read_buf is always
161 	 * called with nbytes > avail, and the two cases above both
162 	 * guarantee p points to at least nbytes bytes.
163 	 */
164 	memcpy(p, argp->p, avail);
165 	next_decode_page(argp);
166 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
167 	argp->p += XDR_QUADLEN(nbytes - avail);
168 	return p;
169 }
170 
171 static int zero_clientid(clientid_t *clid)
172 {
173 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
174 }
175 
176 /**
177  * svcxdr_tmpalloc - allocate memory to be freed after compound processing
178  * @argp: NFSv4 compound argument structure
179  * @p: pointer to be freed (with kfree())
180  *
181  * Marks @p to be freed when processing the compound operation
182  * described in @argp finishes.
183  */
184 static void *
185 svcxdr_tmpalloc(struct nfsd4_compoundargs *argp, u32 len)
186 {
187 	struct svcxdr_tmpbuf *tb;
188 
189 	tb = kmalloc(sizeof(*tb) + len, GFP_KERNEL);
190 	if (!tb)
191 		return NULL;
192 	tb->next = argp->to_free;
193 	argp->to_free = tb;
194 	return tb->buf;
195 }
196 
197 /*
198  * For xdr strings that need to be passed to other kernel api's
199  * as null-terminated strings.
200  *
201  * Note null-terminating in place usually isn't safe since the
202  * buffer might end on a page boundary.
203  */
204 static char *
205 svcxdr_dupstr(struct nfsd4_compoundargs *argp, void *buf, u32 len)
206 {
207 	char *p = svcxdr_tmpalloc(argp, len + 1);
208 
209 	if (!p)
210 		return NULL;
211 	memcpy(p, buf, len);
212 	p[len] = '\0';
213 	return p;
214 }
215 
216 /**
217  * savemem - duplicate a chunk of memory for later processing
218  * @argp: NFSv4 compound argument structure to be freed with
219  * @p: pointer to be duplicated
220  * @nbytes: length to be duplicated
221  *
222  * Returns a pointer to a copy of @nbytes bytes of memory at @p
223  * that are preserved until processing of the NFSv4 compound
224  * operation described by @argp finishes.
225  */
226 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
227 {
228 	void *ret;
229 
230 	ret = svcxdr_tmpalloc(argp, nbytes);
231 	if (!ret)
232 		return NULL;
233 	memcpy(ret, p, nbytes);
234 	return ret;
235 }
236 
237 static __be32
238 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
239 {
240 	u32 bmlen;
241 	DECODE_HEAD;
242 
243 	bmval[0] = 0;
244 	bmval[1] = 0;
245 	bmval[2] = 0;
246 
247 	READ_BUF(4);
248 	bmlen = be32_to_cpup(p++);
249 	if (bmlen > 1000)
250 		goto xdr_error;
251 
252 	READ_BUF(bmlen << 2);
253 	if (bmlen > 0)
254 		bmval[0] = be32_to_cpup(p++);
255 	if (bmlen > 1)
256 		bmval[1] = be32_to_cpup(p++);
257 	if (bmlen > 2)
258 		bmval[2] = be32_to_cpup(p++);
259 
260 	DECODE_TAIL;
261 }
262 
263 static __be32
264 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
265 		   struct iattr *iattr, struct nfs4_acl **acl,
266 		   struct xdr_netobj *label)
267 {
268 	int expected_len, len = 0;
269 	u32 dummy32;
270 	u64 sec;
271 	char *buf;
272 
273 	DECODE_HEAD;
274 	iattr->ia_valid = 0;
275 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
276 		return status;
277 
278 	READ_BUF(4);
279 	expected_len = be32_to_cpup(p++);
280 
281 	if (bmval[0] & FATTR4_WORD0_SIZE) {
282 		READ_BUF(8);
283 		len += 8;
284 		p = xdr_decode_hyper(p, &iattr->ia_size);
285 		iattr->ia_valid |= ATTR_SIZE;
286 	}
287 	if (bmval[0] & FATTR4_WORD0_ACL) {
288 		u32 nace;
289 		struct nfs4_ace *ace;
290 
291 		READ_BUF(4); len += 4;
292 		nace = be32_to_cpup(p++);
293 
294 		if (nace > NFS4_ACL_MAX)
295 			return nfserr_fbig;
296 
297 		*acl = svcxdr_tmpalloc(argp, nfs4_acl_bytes(nace));
298 		if (*acl == NULL)
299 			return nfserr_jukebox;
300 
301 		(*acl)->naces = nace;
302 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
303 			READ_BUF(16); len += 16;
304 			ace->type = be32_to_cpup(p++);
305 			ace->flag = be32_to_cpup(p++);
306 			ace->access_mask = be32_to_cpup(p++);
307 			dummy32 = be32_to_cpup(p++);
308 			READ_BUF(dummy32);
309 			len += XDR_QUADLEN(dummy32) << 2;
310 			READMEM(buf, dummy32);
311 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
312 			status = nfs_ok;
313 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
314 				;
315 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
316 				status = nfsd_map_name_to_gid(argp->rqstp,
317 						buf, dummy32, &ace->who_gid);
318 			else
319 				status = nfsd_map_name_to_uid(argp->rqstp,
320 						buf, dummy32, &ace->who_uid);
321 			if (status)
322 				return status;
323 		}
324 	} else
325 		*acl = NULL;
326 	if (bmval[1] & FATTR4_WORD1_MODE) {
327 		READ_BUF(4);
328 		len += 4;
329 		iattr->ia_mode = be32_to_cpup(p++);
330 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
331 		iattr->ia_valid |= ATTR_MODE;
332 	}
333 	if (bmval[1] & FATTR4_WORD1_OWNER) {
334 		READ_BUF(4);
335 		len += 4;
336 		dummy32 = be32_to_cpup(p++);
337 		READ_BUF(dummy32);
338 		len += (XDR_QUADLEN(dummy32) << 2);
339 		READMEM(buf, dummy32);
340 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
341 			return status;
342 		iattr->ia_valid |= ATTR_UID;
343 	}
344 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
345 		READ_BUF(4);
346 		len += 4;
347 		dummy32 = be32_to_cpup(p++);
348 		READ_BUF(dummy32);
349 		len += (XDR_QUADLEN(dummy32) << 2);
350 		READMEM(buf, dummy32);
351 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
352 			return status;
353 		iattr->ia_valid |= ATTR_GID;
354 	}
355 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
356 		READ_BUF(4);
357 		len += 4;
358 		dummy32 = be32_to_cpup(p++);
359 		switch (dummy32) {
360 		case NFS4_SET_TO_CLIENT_TIME:
361 			/* We require the high 32 bits of 'seconds' to be 0, and we ignore
362 			   all 32 bits of 'nseconds'. */
363 			READ_BUF(12);
364 			len += 12;
365 			p = xdr_decode_hyper(p, &sec);
366 			iattr->ia_atime.tv_sec = (time_t)sec;
367 			iattr->ia_atime.tv_nsec = be32_to_cpup(p++);
368 			if (iattr->ia_atime.tv_nsec >= (u32)1000000000)
369 				return nfserr_inval;
370 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
371 			break;
372 		case NFS4_SET_TO_SERVER_TIME:
373 			iattr->ia_valid |= ATTR_ATIME;
374 			break;
375 		default:
376 			goto xdr_error;
377 		}
378 	}
379 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
380 		READ_BUF(4);
381 		len += 4;
382 		dummy32 = be32_to_cpup(p++);
383 		switch (dummy32) {
384 		case NFS4_SET_TO_CLIENT_TIME:
385 			/* We require the high 32 bits of 'seconds' to be 0, and we ignore
386 			   all 32 bits of 'nseconds'. */
387 			READ_BUF(12);
388 			len += 12;
389 			p = xdr_decode_hyper(p, &sec);
390 			iattr->ia_mtime.tv_sec = sec;
391 			iattr->ia_mtime.tv_nsec = be32_to_cpup(p++);
392 			if (iattr->ia_mtime.tv_nsec >= (u32)1000000000)
393 				return nfserr_inval;
394 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
395 			break;
396 		case NFS4_SET_TO_SERVER_TIME:
397 			iattr->ia_valid |= ATTR_MTIME;
398 			break;
399 		default:
400 			goto xdr_error;
401 		}
402 	}
403 
404 	label->len = 0;
405 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
406 	if (bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
407 		READ_BUF(4);
408 		len += 4;
409 		dummy32 = be32_to_cpup(p++); /* lfs: we don't use it */
410 		READ_BUF(4);
411 		len += 4;
412 		dummy32 = be32_to_cpup(p++); /* pi: we don't use it either */
413 		READ_BUF(4);
414 		len += 4;
415 		dummy32 = be32_to_cpup(p++);
416 		READ_BUF(dummy32);
417 		if (dummy32 > NFSD4_MAX_SEC_LABEL_LEN)
418 			return nfserr_badlabel;
419 		len += (XDR_QUADLEN(dummy32) << 2);
420 		READMEM(buf, dummy32);
421 		label->len = dummy32;
422 		label->data = svcxdr_dupstr(argp, buf, dummy32);
423 		if (!label->data)
424 			return nfserr_jukebox;
425 	}
426 #endif
427 
428 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
429 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
430 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2)
431 		READ_BUF(expected_len - len);
432 	else if (len != expected_len)
433 		goto xdr_error;
434 
435 	DECODE_TAIL;
436 }
437 
438 static __be32
439 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
440 {
441 	DECODE_HEAD;
442 
443 	READ_BUF(sizeof(stateid_t));
444 	sid->si_generation = be32_to_cpup(p++);
445 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
446 
447 	DECODE_TAIL;
448 }
449 
450 static __be32
451 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
452 {
453 	DECODE_HEAD;
454 
455 	READ_BUF(4);
456 	access->ac_req_access = be32_to_cpup(p++);
457 
458 	DECODE_TAIL;
459 }
460 
461 static __be32 nfsd4_decode_cb_sec(struct nfsd4_compoundargs *argp, struct nfsd4_cb_sec *cbs)
462 {
463 	DECODE_HEAD;
464 	u32 dummy, uid, gid;
465 	char *machine_name;
466 	int i;
467 	int nr_secflavs;
468 
469 	/* callback_sec_params4 */
470 	READ_BUF(4);
471 	nr_secflavs = be32_to_cpup(p++);
472 	if (nr_secflavs)
473 		cbs->flavor = (u32)(-1);
474 	else
475 		/* Is this legal? Be generous, take it to mean AUTH_NONE: */
476 		cbs->flavor = 0;
477 	for (i = 0; i < nr_secflavs; ++i) {
478 		READ_BUF(4);
479 		dummy = be32_to_cpup(p++);
480 		switch (dummy) {
481 		case RPC_AUTH_NULL:
482 			/* Nothing to read */
483 			if (cbs->flavor == (u32)(-1))
484 				cbs->flavor = RPC_AUTH_NULL;
485 			break;
486 		case RPC_AUTH_UNIX:
487 			READ_BUF(8);
488 			/* stamp */
489 			dummy = be32_to_cpup(p++);
490 
491 			/* machine name */
492 			dummy = be32_to_cpup(p++);
493 			READ_BUF(dummy);
494 			SAVEMEM(machine_name, dummy);
495 
496 			/* uid, gid */
497 			READ_BUF(8);
498 			uid = be32_to_cpup(p++);
499 			gid = be32_to_cpup(p++);
500 
501 			/* more gids */
502 			READ_BUF(4);
503 			dummy = be32_to_cpup(p++);
504 			READ_BUF(dummy * 4);
505 			if (cbs->flavor == (u32)(-1)) {
506 				kuid_t kuid = make_kuid(&init_user_ns, uid);
507 				kgid_t kgid = make_kgid(&init_user_ns, gid);
508 				if (uid_valid(kuid) && gid_valid(kgid)) {
509 					cbs->uid = kuid;
510 					cbs->gid = kgid;
511 					cbs->flavor = RPC_AUTH_UNIX;
512 				} else {
513 					dprintk("RPC_AUTH_UNIX with invalid"
514 						"uid or gid ignoring!\n");
515 				}
516 			}
517 			break;
518 		case RPC_AUTH_GSS:
519 			dprintk("RPC_AUTH_GSS callback secflavor "
520 				"not supported!\n");
521 			READ_BUF(8);
522 			/* gcbp_service */
523 			dummy = be32_to_cpup(p++);
524 			/* gcbp_handle_from_server */
525 			dummy = be32_to_cpup(p++);
526 			READ_BUF(dummy);
527 			p += XDR_QUADLEN(dummy);
528 			/* gcbp_handle_from_client */
529 			READ_BUF(4);
530 			dummy = be32_to_cpup(p++);
531 			READ_BUF(dummy);
532 			break;
533 		default:
534 			dprintk("Illegal callback secflavor\n");
535 			return nfserr_inval;
536 		}
537 	}
538 	DECODE_TAIL;
539 }
540 
541 static __be32 nfsd4_decode_backchannel_ctl(struct nfsd4_compoundargs *argp, struct nfsd4_backchannel_ctl *bc)
542 {
543 	DECODE_HEAD;
544 
545 	READ_BUF(4);
546 	bc->bc_cb_program = be32_to_cpup(p++);
547 	nfsd4_decode_cb_sec(argp, &bc->bc_cb_sec);
548 
549 	DECODE_TAIL;
550 }
551 
552 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
553 {
554 	DECODE_HEAD;
555 
556 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
557 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
558 	bcts->dir = be32_to_cpup(p++);
559 	/* XXX: skipping ctsa_use_conn_in_rdma_mode.  Perhaps Tom Tucker
560 	 * could help us figure out we should be using it. */
561 	DECODE_TAIL;
562 }
563 
564 static __be32
565 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
566 {
567 	DECODE_HEAD;
568 
569 	READ_BUF(4);
570 	close->cl_seqid = be32_to_cpup(p++);
571 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
572 
573 	DECODE_TAIL;
574 }
575 
576 
577 static __be32
578 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
579 {
580 	DECODE_HEAD;
581 
582 	READ_BUF(12);
583 	p = xdr_decode_hyper(p, &commit->co_offset);
584 	commit->co_count = be32_to_cpup(p++);
585 
586 	DECODE_TAIL;
587 }
588 
589 static __be32
590 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
591 {
592 	DECODE_HEAD;
593 
594 	READ_BUF(4);
595 	create->cr_type = be32_to_cpup(p++);
596 	switch (create->cr_type) {
597 	case NF4LNK:
598 		READ_BUF(4);
599 		create->cr_datalen = be32_to_cpup(p++);
600 		READ_BUF(create->cr_datalen);
601 		create->cr_data = svcxdr_dupstr(argp, p, create->cr_datalen);
602 		if (!create->cr_data)
603 			return nfserr_jukebox;
604 		break;
605 	case NF4BLK:
606 	case NF4CHR:
607 		READ_BUF(8);
608 		create->cr_specdata1 = be32_to_cpup(p++);
609 		create->cr_specdata2 = be32_to_cpup(p++);
610 		break;
611 	case NF4SOCK:
612 	case NF4FIFO:
613 	case NF4DIR:
614 	default:
615 		break;
616 	}
617 
618 	READ_BUF(4);
619 	create->cr_namelen = be32_to_cpup(p++);
620 	READ_BUF(create->cr_namelen);
621 	SAVEMEM(create->cr_name, create->cr_namelen);
622 	if ((status = check_filename(create->cr_name, create->cr_namelen)))
623 		return status;
624 
625 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
626 				    &create->cr_acl, &create->cr_label);
627 	if (status)
628 		goto out;
629 
630 	DECODE_TAIL;
631 }
632 
633 static inline __be32
634 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
635 {
636 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
637 }
638 
639 static inline __be32
640 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
641 {
642 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
643 }
644 
645 static __be32
646 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
647 {
648 	DECODE_HEAD;
649 
650 	READ_BUF(4);
651 	link->li_namelen = be32_to_cpup(p++);
652 	READ_BUF(link->li_namelen);
653 	SAVEMEM(link->li_name, link->li_namelen);
654 	if ((status = check_filename(link->li_name, link->li_namelen)))
655 		return status;
656 
657 	DECODE_TAIL;
658 }
659 
660 static __be32
661 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
662 {
663 	DECODE_HEAD;
664 
665 	/*
666 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
667 	*/
668 	READ_BUF(28);
669 	lock->lk_type = be32_to_cpup(p++);
670 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
671 		goto xdr_error;
672 	lock->lk_reclaim = be32_to_cpup(p++);
673 	p = xdr_decode_hyper(p, &lock->lk_offset);
674 	p = xdr_decode_hyper(p, &lock->lk_length);
675 	lock->lk_is_new = be32_to_cpup(p++);
676 
677 	if (lock->lk_is_new) {
678 		READ_BUF(4);
679 		lock->lk_new_open_seqid = be32_to_cpup(p++);
680 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
681 		if (status)
682 			return status;
683 		READ_BUF(8 + sizeof(clientid_t));
684 		lock->lk_new_lock_seqid = be32_to_cpup(p++);
685 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
686 		lock->lk_new_owner.len = be32_to_cpup(p++);
687 		READ_BUF(lock->lk_new_owner.len);
688 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
689 	} else {
690 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
691 		if (status)
692 			return status;
693 		READ_BUF(4);
694 		lock->lk_old_lock_seqid = be32_to_cpup(p++);
695 	}
696 
697 	DECODE_TAIL;
698 }
699 
700 static __be32
701 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
702 {
703 	DECODE_HEAD;
704 
705 	READ_BUF(32);
706 	lockt->lt_type = be32_to_cpup(p++);
707 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
708 		goto xdr_error;
709 	p = xdr_decode_hyper(p, &lockt->lt_offset);
710 	p = xdr_decode_hyper(p, &lockt->lt_length);
711 	COPYMEM(&lockt->lt_clientid, 8);
712 	lockt->lt_owner.len = be32_to_cpup(p++);
713 	READ_BUF(lockt->lt_owner.len);
714 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
715 
716 	DECODE_TAIL;
717 }
718 
719 static __be32
720 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
721 {
722 	DECODE_HEAD;
723 
724 	READ_BUF(8);
725 	locku->lu_type = be32_to_cpup(p++);
726 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
727 		goto xdr_error;
728 	locku->lu_seqid = be32_to_cpup(p++);
729 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
730 	if (status)
731 		return status;
732 	READ_BUF(16);
733 	p = xdr_decode_hyper(p, &locku->lu_offset);
734 	p = xdr_decode_hyper(p, &locku->lu_length);
735 
736 	DECODE_TAIL;
737 }
738 
739 static __be32
740 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
741 {
742 	DECODE_HEAD;
743 
744 	READ_BUF(4);
745 	lookup->lo_len = be32_to_cpup(p++);
746 	READ_BUF(lookup->lo_len);
747 	SAVEMEM(lookup->lo_name, lookup->lo_len);
748 	if ((status = check_filename(lookup->lo_name, lookup->lo_len)))
749 		return status;
750 
751 	DECODE_TAIL;
752 }
753 
754 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
755 {
756 	__be32 *p;
757 	u32 w;
758 
759 	READ_BUF(4);
760 	w = be32_to_cpup(p++);
761 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
762 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
763 	if (deleg_when)
764 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
765 
766 	switch (w & NFS4_SHARE_ACCESS_MASK) {
767 	case NFS4_SHARE_ACCESS_READ:
768 	case NFS4_SHARE_ACCESS_WRITE:
769 	case NFS4_SHARE_ACCESS_BOTH:
770 		break;
771 	default:
772 		return nfserr_bad_xdr;
773 	}
774 	w &= ~NFS4_SHARE_ACCESS_MASK;
775 	if (!w)
776 		return nfs_ok;
777 	if (!argp->minorversion)
778 		return nfserr_bad_xdr;
779 	switch (w & NFS4_SHARE_WANT_MASK) {
780 	case NFS4_SHARE_WANT_NO_PREFERENCE:
781 	case NFS4_SHARE_WANT_READ_DELEG:
782 	case NFS4_SHARE_WANT_WRITE_DELEG:
783 	case NFS4_SHARE_WANT_ANY_DELEG:
784 	case NFS4_SHARE_WANT_NO_DELEG:
785 	case NFS4_SHARE_WANT_CANCEL:
786 		break;
787 	default:
788 		return nfserr_bad_xdr;
789 	}
790 	w &= ~NFS4_SHARE_WANT_MASK;
791 	if (!w)
792 		return nfs_ok;
793 
794 	if (!deleg_when)	/* open_downgrade */
795 		return nfserr_inval;
796 	switch (w) {
797 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
798 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
799 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
800 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
801 		return nfs_ok;
802 	}
803 xdr_error:
804 	return nfserr_bad_xdr;
805 }
806 
807 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
808 {
809 	__be32 *p;
810 
811 	READ_BUF(4);
812 	*x = be32_to_cpup(p++);
813 	/* Note: unlinke access bits, deny bits may be zero. */
814 	if (*x & ~NFS4_SHARE_DENY_BOTH)
815 		return nfserr_bad_xdr;
816 	return nfs_ok;
817 xdr_error:
818 	return nfserr_bad_xdr;
819 }
820 
821 static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
822 {
823 	__be32 *p;
824 
825 	READ_BUF(4);
826 	o->len = be32_to_cpup(p++);
827 
828 	if (o->len == 0 || o->len > NFS4_OPAQUE_LIMIT)
829 		return nfserr_bad_xdr;
830 
831 	READ_BUF(o->len);
832 	SAVEMEM(o->data, o->len);
833 	return nfs_ok;
834 xdr_error:
835 	return nfserr_bad_xdr;
836 }
837 
838 static __be32
839 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
840 {
841 	DECODE_HEAD;
842 	u32 dummy;
843 
844 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
845 	open->op_iattr.ia_valid = 0;
846 	open->op_openowner = NULL;
847 
848 	open->op_xdr_error = 0;
849 	/* seqid, share_access, share_deny, clientid, ownerlen */
850 	READ_BUF(4);
851 	open->op_seqid = be32_to_cpup(p++);
852 	/* decode, yet ignore deleg_when until supported */
853 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
854 					   &open->op_deleg_want, &dummy);
855 	if (status)
856 		goto xdr_error;
857 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
858 	if (status)
859 		goto xdr_error;
860 	READ_BUF(sizeof(clientid_t));
861 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
862 	status = nfsd4_decode_opaque(argp, &open->op_owner);
863 	if (status)
864 		goto xdr_error;
865 	READ_BUF(4);
866 	open->op_create = be32_to_cpup(p++);
867 	switch (open->op_create) {
868 	case NFS4_OPEN_NOCREATE:
869 		break;
870 	case NFS4_OPEN_CREATE:
871 		READ_BUF(4);
872 		open->op_createmode = be32_to_cpup(p++);
873 		switch (open->op_createmode) {
874 		case NFS4_CREATE_UNCHECKED:
875 		case NFS4_CREATE_GUARDED:
876 			status = nfsd4_decode_fattr(argp, open->op_bmval,
877 				&open->op_iattr, &open->op_acl, &open->op_label);
878 			if (status)
879 				goto out;
880 			break;
881 		case NFS4_CREATE_EXCLUSIVE:
882 			READ_BUF(NFS4_VERIFIER_SIZE);
883 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
884 			break;
885 		case NFS4_CREATE_EXCLUSIVE4_1:
886 			if (argp->minorversion < 1)
887 				goto xdr_error;
888 			READ_BUF(NFS4_VERIFIER_SIZE);
889 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
890 			status = nfsd4_decode_fattr(argp, open->op_bmval,
891 				&open->op_iattr, &open->op_acl, &open->op_label);
892 			if (status)
893 				goto out;
894 			break;
895 		default:
896 			goto xdr_error;
897 		}
898 		break;
899 	default:
900 		goto xdr_error;
901 	}
902 
903 	/* open_claim */
904 	READ_BUF(4);
905 	open->op_claim_type = be32_to_cpup(p++);
906 	switch (open->op_claim_type) {
907 	case NFS4_OPEN_CLAIM_NULL:
908 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
909 		READ_BUF(4);
910 		open->op_fname.len = be32_to_cpup(p++);
911 		READ_BUF(open->op_fname.len);
912 		SAVEMEM(open->op_fname.data, open->op_fname.len);
913 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
914 			return status;
915 		break;
916 	case NFS4_OPEN_CLAIM_PREVIOUS:
917 		READ_BUF(4);
918 		open->op_delegate_type = be32_to_cpup(p++);
919 		break;
920 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
921 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
922 		if (status)
923 			return status;
924 		READ_BUF(4);
925 		open->op_fname.len = be32_to_cpup(p++);
926 		READ_BUF(open->op_fname.len);
927 		SAVEMEM(open->op_fname.data, open->op_fname.len);
928 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
929 			return status;
930 		break;
931 	case NFS4_OPEN_CLAIM_FH:
932 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
933 		if (argp->minorversion < 1)
934 			goto xdr_error;
935 		/* void */
936 		break;
937 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
938 		if (argp->minorversion < 1)
939 			goto xdr_error;
940 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
941 		if (status)
942 			return status;
943 		break;
944 	default:
945 		goto xdr_error;
946 	}
947 
948 	DECODE_TAIL;
949 }
950 
951 static __be32
952 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
953 {
954 	DECODE_HEAD;
955 
956 	if (argp->minorversion >= 1)
957 		return nfserr_notsupp;
958 
959 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
960 	if (status)
961 		return status;
962 	READ_BUF(4);
963 	open_conf->oc_seqid = be32_to_cpup(p++);
964 
965 	DECODE_TAIL;
966 }
967 
968 static __be32
969 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
970 {
971 	DECODE_HEAD;
972 
973 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
974 	if (status)
975 		return status;
976 	READ_BUF(4);
977 	open_down->od_seqid = be32_to_cpup(p++);
978 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
979 					   &open_down->od_deleg_want, NULL);
980 	if (status)
981 		return status;
982 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
983 	if (status)
984 		return status;
985 	DECODE_TAIL;
986 }
987 
988 static __be32
989 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
990 {
991 	DECODE_HEAD;
992 
993 	READ_BUF(4);
994 	putfh->pf_fhlen = be32_to_cpup(p++);
995 	if (putfh->pf_fhlen > NFS4_FHSIZE)
996 		goto xdr_error;
997 	READ_BUF(putfh->pf_fhlen);
998 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
999 
1000 	DECODE_TAIL;
1001 }
1002 
1003 static __be32
1004 nfsd4_decode_putpubfh(struct nfsd4_compoundargs *argp, void *p)
1005 {
1006 	if (argp->minorversion == 0)
1007 		return nfs_ok;
1008 	return nfserr_notsupp;
1009 }
1010 
1011 static __be32
1012 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
1013 {
1014 	DECODE_HEAD;
1015 
1016 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
1017 	if (status)
1018 		return status;
1019 	READ_BUF(12);
1020 	p = xdr_decode_hyper(p, &read->rd_offset);
1021 	read->rd_length = be32_to_cpup(p++);
1022 
1023 	DECODE_TAIL;
1024 }
1025 
1026 static __be32
1027 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
1028 {
1029 	DECODE_HEAD;
1030 
1031 	READ_BUF(24);
1032 	p = xdr_decode_hyper(p, &readdir->rd_cookie);
1033 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
1034 	readdir->rd_dircount = be32_to_cpup(p++);
1035 	readdir->rd_maxcount = be32_to_cpup(p++);
1036 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
1037 		goto out;
1038 
1039 	DECODE_TAIL;
1040 }
1041 
1042 static __be32
1043 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
1044 {
1045 	DECODE_HEAD;
1046 
1047 	READ_BUF(4);
1048 	remove->rm_namelen = be32_to_cpup(p++);
1049 	READ_BUF(remove->rm_namelen);
1050 	SAVEMEM(remove->rm_name, remove->rm_namelen);
1051 	if ((status = check_filename(remove->rm_name, remove->rm_namelen)))
1052 		return status;
1053 
1054 	DECODE_TAIL;
1055 }
1056 
1057 static __be32
1058 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
1059 {
1060 	DECODE_HEAD;
1061 
1062 	READ_BUF(4);
1063 	rename->rn_snamelen = be32_to_cpup(p++);
1064 	READ_BUF(rename->rn_snamelen + 4);
1065 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1066 	rename->rn_tnamelen = be32_to_cpup(p++);
1067 	READ_BUF(rename->rn_tnamelen);
1068 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1069 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1070 		return status;
1071 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1072 		return status;
1073 
1074 	DECODE_TAIL;
1075 }
1076 
1077 static __be32
1078 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1079 {
1080 	DECODE_HEAD;
1081 
1082 	if (argp->minorversion >= 1)
1083 		return nfserr_notsupp;
1084 
1085 	READ_BUF(sizeof(clientid_t));
1086 	COPYMEM(clientid, sizeof(clientid_t));
1087 
1088 	DECODE_TAIL;
1089 }
1090 
1091 static __be32
1092 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1093 		     struct nfsd4_secinfo *secinfo)
1094 {
1095 	DECODE_HEAD;
1096 
1097 	READ_BUF(4);
1098 	secinfo->si_namelen = be32_to_cpup(p++);
1099 	READ_BUF(secinfo->si_namelen);
1100 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1101 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1102 	if (status)
1103 		return status;
1104 	DECODE_TAIL;
1105 }
1106 
1107 static __be32
1108 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1109 		     struct nfsd4_secinfo_no_name *sin)
1110 {
1111 	DECODE_HEAD;
1112 
1113 	READ_BUF(4);
1114 	sin->sin_style = be32_to_cpup(p++);
1115 	DECODE_TAIL;
1116 }
1117 
1118 static __be32
1119 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1120 {
1121 	__be32 status;
1122 
1123 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1124 	if (status)
1125 		return status;
1126 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1127 				  &setattr->sa_acl, &setattr->sa_label);
1128 }
1129 
1130 static __be32
1131 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1132 {
1133 	DECODE_HEAD;
1134 
1135 	if (argp->minorversion >= 1)
1136 		return nfserr_notsupp;
1137 
1138 	READ_BUF(NFS4_VERIFIER_SIZE);
1139 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1140 
1141 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1142 	if (status)
1143 		return nfserr_bad_xdr;
1144 	READ_BUF(8);
1145 	setclientid->se_callback_prog = be32_to_cpup(p++);
1146 	setclientid->se_callback_netid_len = be32_to_cpup(p++);
1147 
1148 	READ_BUF(setclientid->se_callback_netid_len + 4);
1149 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1150 	setclientid->se_callback_addr_len = be32_to_cpup(p++);
1151 
1152 	READ_BUF(setclientid->se_callback_addr_len + 4);
1153 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1154 	setclientid->se_callback_ident = be32_to_cpup(p++);
1155 
1156 	DECODE_TAIL;
1157 }
1158 
1159 static __be32
1160 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1161 {
1162 	DECODE_HEAD;
1163 
1164 	if (argp->minorversion >= 1)
1165 		return nfserr_notsupp;
1166 
1167 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1168 	COPYMEM(&scd_c->sc_clientid, 8);
1169 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1170 
1171 	DECODE_TAIL;
1172 }
1173 
1174 /* Also used for NVERIFY */
1175 static __be32
1176 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1177 {
1178 	DECODE_HEAD;
1179 
1180 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1181 		goto out;
1182 
1183 	/* For convenience's sake, we compare raw xdr'd attributes in
1184 	 * nfsd4_proc_verify */
1185 
1186 	READ_BUF(4);
1187 	verify->ve_attrlen = be32_to_cpup(p++);
1188 	READ_BUF(verify->ve_attrlen);
1189 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1190 
1191 	DECODE_TAIL;
1192 }
1193 
1194 static __be32
1195 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1196 {
1197 	int avail;
1198 	int len;
1199 	DECODE_HEAD;
1200 
1201 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1202 	if (status)
1203 		return status;
1204 	READ_BUF(16);
1205 	p = xdr_decode_hyper(p, &write->wr_offset);
1206 	write->wr_stable_how = be32_to_cpup(p++);
1207 	if (write->wr_stable_how > 2)
1208 		goto xdr_error;
1209 	write->wr_buflen = be32_to_cpup(p++);
1210 
1211 	/* Sorry .. no magic macros for this.. *
1212 	 * READ_BUF(write->wr_buflen);
1213 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1214 	 */
1215 	avail = (char*)argp->end - (char*)argp->p;
1216 	if (avail + argp->pagelen < write->wr_buflen) {
1217 		dprintk("NFSD: xdr error (%s:%d)\n",
1218 				__FILE__, __LINE__);
1219 		goto xdr_error;
1220 	}
1221 	write->wr_head.iov_base = p;
1222 	write->wr_head.iov_len = avail;
1223 	write->wr_pagelist = argp->pagelist;
1224 
1225 	len = XDR_QUADLEN(write->wr_buflen) << 2;
1226 	if (len >= avail) {
1227 		int pages;
1228 
1229 		len -= avail;
1230 
1231 		pages = len >> PAGE_SHIFT;
1232 		argp->pagelist += pages;
1233 		argp->pagelen -= pages * PAGE_SIZE;
1234 		len -= pages * PAGE_SIZE;
1235 
1236 		argp->p = (__be32 *)page_address(argp->pagelist[0]);
1237 		argp->pagelist++;
1238 		argp->end = argp->p + XDR_QUADLEN(PAGE_SIZE);
1239 	}
1240 	argp->p += XDR_QUADLEN(len);
1241 
1242 	DECODE_TAIL;
1243 }
1244 
1245 static __be32
1246 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1247 {
1248 	DECODE_HEAD;
1249 
1250 	if (argp->minorversion >= 1)
1251 		return nfserr_notsupp;
1252 
1253 	READ_BUF(12);
1254 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1255 	rlockowner->rl_owner.len = be32_to_cpup(p++);
1256 	READ_BUF(rlockowner->rl_owner.len);
1257 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1258 
1259 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1260 		return nfserr_inval;
1261 	DECODE_TAIL;
1262 }
1263 
1264 static __be32
1265 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1266 			 struct nfsd4_exchange_id *exid)
1267 {
1268 	int dummy, tmp;
1269 	DECODE_HEAD;
1270 
1271 	READ_BUF(NFS4_VERIFIER_SIZE);
1272 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1273 
1274 	status = nfsd4_decode_opaque(argp, &exid->clname);
1275 	if (status)
1276 		return nfserr_bad_xdr;
1277 
1278 	READ_BUF(4);
1279 	exid->flags = be32_to_cpup(p++);
1280 
1281 	/* Ignore state_protect4_a */
1282 	READ_BUF(4);
1283 	exid->spa_how = be32_to_cpup(p++);
1284 	switch (exid->spa_how) {
1285 	case SP4_NONE:
1286 		break;
1287 	case SP4_MACH_CRED:
1288 		/* spo_must_enforce */
1289 		READ_BUF(4);
1290 		dummy = be32_to_cpup(p++);
1291 		READ_BUF(dummy * 4);
1292 		p += dummy;
1293 
1294 		/* spo_must_allow */
1295 		READ_BUF(4);
1296 		dummy = be32_to_cpup(p++);
1297 		READ_BUF(dummy * 4);
1298 		p += dummy;
1299 		break;
1300 	case SP4_SSV:
1301 		/* ssp_ops */
1302 		READ_BUF(4);
1303 		dummy = be32_to_cpup(p++);
1304 		READ_BUF(dummy * 4);
1305 		p += dummy;
1306 
1307 		READ_BUF(4);
1308 		dummy = be32_to_cpup(p++);
1309 		READ_BUF(dummy * 4);
1310 		p += dummy;
1311 
1312 		/* ssp_hash_algs<> */
1313 		READ_BUF(4);
1314 		tmp = be32_to_cpup(p++);
1315 		while (tmp--) {
1316 			READ_BUF(4);
1317 			dummy = be32_to_cpup(p++);
1318 			READ_BUF(dummy);
1319 			p += XDR_QUADLEN(dummy);
1320 		}
1321 
1322 		/* ssp_encr_algs<> */
1323 		READ_BUF(4);
1324 		tmp = be32_to_cpup(p++);
1325 		while (tmp--) {
1326 			READ_BUF(4);
1327 			dummy = be32_to_cpup(p++);
1328 			READ_BUF(dummy);
1329 			p += XDR_QUADLEN(dummy);
1330 		}
1331 
1332 		/* ssp_window and ssp_num_gss_handles */
1333 		READ_BUF(8);
1334 		dummy = be32_to_cpup(p++);
1335 		dummy = be32_to_cpup(p++);
1336 		break;
1337 	default:
1338 		goto xdr_error;
1339 	}
1340 
1341 	/* Ignore Implementation ID */
1342 	READ_BUF(4);    /* nfs_impl_id4 array length */
1343 	dummy = be32_to_cpup(p++);
1344 
1345 	if (dummy > 1)
1346 		goto xdr_error;
1347 
1348 	if (dummy == 1) {
1349 		/* nii_domain */
1350 		READ_BUF(4);
1351 		dummy = be32_to_cpup(p++);
1352 		READ_BUF(dummy);
1353 		p += XDR_QUADLEN(dummy);
1354 
1355 		/* nii_name */
1356 		READ_BUF(4);
1357 		dummy = be32_to_cpup(p++);
1358 		READ_BUF(dummy);
1359 		p += XDR_QUADLEN(dummy);
1360 
1361 		/* nii_date */
1362 		READ_BUF(12);
1363 		p += 3;
1364 	}
1365 	DECODE_TAIL;
1366 }
1367 
1368 static __be32
1369 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1370 			    struct nfsd4_create_session *sess)
1371 {
1372 	DECODE_HEAD;
1373 	u32 dummy;
1374 
1375 	READ_BUF(16);
1376 	COPYMEM(&sess->clientid, 8);
1377 	sess->seqid = be32_to_cpup(p++);
1378 	sess->flags = be32_to_cpup(p++);
1379 
1380 	/* Fore channel attrs */
1381 	READ_BUF(28);
1382 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1383 	sess->fore_channel.maxreq_sz = be32_to_cpup(p++);
1384 	sess->fore_channel.maxresp_sz = be32_to_cpup(p++);
1385 	sess->fore_channel.maxresp_cached = be32_to_cpup(p++);
1386 	sess->fore_channel.maxops = be32_to_cpup(p++);
1387 	sess->fore_channel.maxreqs = be32_to_cpup(p++);
1388 	sess->fore_channel.nr_rdma_attrs = be32_to_cpup(p++);
1389 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1390 		READ_BUF(4);
1391 		sess->fore_channel.rdma_attrs = be32_to_cpup(p++);
1392 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1393 		dprintk("Too many fore channel attr bitmaps!\n");
1394 		goto xdr_error;
1395 	}
1396 
1397 	/* Back channel attrs */
1398 	READ_BUF(28);
1399 	dummy = be32_to_cpup(p++); /* headerpadsz is always 0 */
1400 	sess->back_channel.maxreq_sz = be32_to_cpup(p++);
1401 	sess->back_channel.maxresp_sz = be32_to_cpup(p++);
1402 	sess->back_channel.maxresp_cached = be32_to_cpup(p++);
1403 	sess->back_channel.maxops = be32_to_cpup(p++);
1404 	sess->back_channel.maxreqs = be32_to_cpup(p++);
1405 	sess->back_channel.nr_rdma_attrs = be32_to_cpup(p++);
1406 	if (sess->back_channel.nr_rdma_attrs == 1) {
1407 		READ_BUF(4);
1408 		sess->back_channel.rdma_attrs = be32_to_cpup(p++);
1409 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1410 		dprintk("Too many back channel attr bitmaps!\n");
1411 		goto xdr_error;
1412 	}
1413 
1414 	READ_BUF(4);
1415 	sess->callback_prog = be32_to_cpup(p++);
1416 	nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1417 	DECODE_TAIL;
1418 }
1419 
1420 static __be32
1421 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1422 			     struct nfsd4_destroy_session *destroy_session)
1423 {
1424 	DECODE_HEAD;
1425 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1426 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1427 
1428 	DECODE_TAIL;
1429 }
1430 
1431 static __be32
1432 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1433 			  struct nfsd4_free_stateid *free_stateid)
1434 {
1435 	DECODE_HEAD;
1436 
1437 	READ_BUF(sizeof(stateid_t));
1438 	free_stateid->fr_stateid.si_generation = be32_to_cpup(p++);
1439 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1440 
1441 	DECODE_TAIL;
1442 }
1443 
1444 static __be32
1445 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1446 		      struct nfsd4_sequence *seq)
1447 {
1448 	DECODE_HEAD;
1449 
1450 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1451 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1452 	seq->seqid = be32_to_cpup(p++);
1453 	seq->slotid = be32_to_cpup(p++);
1454 	seq->maxslots = be32_to_cpup(p++);
1455 	seq->cachethis = be32_to_cpup(p++);
1456 
1457 	DECODE_TAIL;
1458 }
1459 
1460 static __be32
1461 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1462 {
1463 	int i;
1464 	__be32 *p, status;
1465 	struct nfsd4_test_stateid_id *stateid;
1466 
1467 	READ_BUF(4);
1468 	test_stateid->ts_num_ids = ntohl(*p++);
1469 
1470 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1471 
1472 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1473 		stateid = svcxdr_tmpalloc(argp, sizeof(*stateid));
1474 		if (!stateid) {
1475 			status = nfserrno(-ENOMEM);
1476 			goto out;
1477 		}
1478 
1479 		INIT_LIST_HEAD(&stateid->ts_id_list);
1480 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1481 
1482 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1483 		if (status)
1484 			goto out;
1485 	}
1486 
1487 	status = 0;
1488 out:
1489 	return status;
1490 xdr_error:
1491 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1492 	status = nfserr_bad_xdr;
1493 	goto out;
1494 }
1495 
1496 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1497 {
1498 	DECODE_HEAD;
1499 
1500 	READ_BUF(8);
1501 	COPYMEM(&dc->clientid, 8);
1502 
1503 	DECODE_TAIL;
1504 }
1505 
1506 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1507 {
1508 	DECODE_HEAD;
1509 
1510 	READ_BUF(4);
1511 	rc->rca_one_fs = be32_to_cpup(p++);
1512 
1513 	DECODE_TAIL;
1514 }
1515 
1516 static __be32
1517 nfsd4_decode_fallocate(struct nfsd4_compoundargs *argp,
1518 		       struct nfsd4_fallocate *fallocate)
1519 {
1520 	DECODE_HEAD;
1521 
1522 	status = nfsd4_decode_stateid(argp, &fallocate->falloc_stateid);
1523 	if (status)
1524 		return status;
1525 
1526 	READ_BUF(16);
1527 	p = xdr_decode_hyper(p, &fallocate->falloc_offset);
1528 	xdr_decode_hyper(p, &fallocate->falloc_length);
1529 
1530 	DECODE_TAIL;
1531 }
1532 
1533 static __be32
1534 nfsd4_decode_seek(struct nfsd4_compoundargs *argp, struct nfsd4_seek *seek)
1535 {
1536 	DECODE_HEAD;
1537 
1538 	status = nfsd4_decode_stateid(argp, &seek->seek_stateid);
1539 	if (status)
1540 		return status;
1541 
1542 	READ_BUF(8 + 4);
1543 	p = xdr_decode_hyper(p, &seek->seek_offset);
1544 	seek->seek_whence = be32_to_cpup(p);
1545 
1546 	DECODE_TAIL;
1547 }
1548 
1549 static __be32
1550 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1551 {
1552 	return nfs_ok;
1553 }
1554 
1555 static __be32
1556 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1557 {
1558 	return nfserr_notsupp;
1559 }
1560 
1561 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1562 
1563 static nfsd4_dec nfsd4_dec_ops[] = {
1564 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1565 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1566 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1567 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1568 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1569 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1570 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1571 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1572 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1573 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1574 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1575 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1576 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1577 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1578 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1579 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1580 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1581 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1582 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1583 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1584 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_putpubfh,
1585 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1586 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1587 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1588 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1589 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1590 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1591 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1592 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1593 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1594 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1595 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1596 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1597 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1598 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1599 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1600 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1601 
1602 	/* new operations for NFSv4.1 */
1603 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_backchannel_ctl,
1604 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1605 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1606 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1607 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1608 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
1609 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1610 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1611 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1612 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1613 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1614 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1615 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1616 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1617 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1618 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
1619 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1620 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
1621 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1622 
1623 	/* new operations for NFSv4.2 */
1624 	[OP_ALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1625 	[OP_COPY]		= (nfsd4_dec)nfsd4_decode_notsupp,
1626 	[OP_COPY_NOTIFY]	= (nfsd4_dec)nfsd4_decode_notsupp,
1627 	[OP_DEALLOCATE]		= (nfsd4_dec)nfsd4_decode_fallocate,
1628 	[OP_IO_ADVISE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1629 	[OP_LAYOUTERROR]	= (nfsd4_dec)nfsd4_decode_notsupp,
1630 	[OP_LAYOUTSTATS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1631 	[OP_OFFLOAD_CANCEL]	= (nfsd4_dec)nfsd4_decode_notsupp,
1632 	[OP_OFFLOAD_STATUS]	= (nfsd4_dec)nfsd4_decode_notsupp,
1633 	[OP_READ_PLUS]		= (nfsd4_dec)nfsd4_decode_notsupp,
1634 	[OP_SEEK]		= (nfsd4_dec)nfsd4_decode_seek,
1635 	[OP_WRITE_SAME]		= (nfsd4_dec)nfsd4_decode_notsupp,
1636 };
1637 
1638 static inline bool
1639 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
1640 {
1641 	if (op->opnum < FIRST_NFS4_OP)
1642 		return false;
1643 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
1644 		return false;
1645 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
1646 		return false;
1647 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
1648 		return false;
1649 	return true;
1650 }
1651 
1652 static __be32
1653 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1654 {
1655 	DECODE_HEAD;
1656 	struct nfsd4_op *op;
1657 	bool cachethis = false;
1658 	int auth_slack= argp->rqstp->rq_auth_slack;
1659 	int max_reply = auth_slack + 8; /* opcnt, status */
1660 	int readcount = 0;
1661 	int readbytes = 0;
1662 	int i;
1663 
1664 	READ_BUF(4);
1665 	argp->taglen = be32_to_cpup(p++);
1666 	READ_BUF(argp->taglen + 8);
1667 	SAVEMEM(argp->tag, argp->taglen);
1668 	argp->minorversion = be32_to_cpup(p++);
1669 	argp->opcnt = be32_to_cpup(p++);
1670 	max_reply += 4 + (XDR_QUADLEN(argp->taglen) << 2);
1671 
1672 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1673 		goto xdr_error;
1674 	if (argp->opcnt > 100)
1675 		goto xdr_error;
1676 
1677 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1678 		argp->ops = kzalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1679 		if (!argp->ops) {
1680 			argp->ops = argp->iops;
1681 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1682 			goto xdr_error;
1683 		}
1684 	}
1685 
1686 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
1687 		argp->opcnt = 0;
1688 
1689 	for (i = 0; i < argp->opcnt; i++) {
1690 		op = &argp->ops[i];
1691 		op->replay = NULL;
1692 
1693 		READ_BUF(4);
1694 		op->opnum = be32_to_cpup(p++);
1695 
1696 		if (nfsd4_opnum_in_range(argp, op))
1697 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
1698 		else {
1699 			op->opnum = OP_ILLEGAL;
1700 			op->status = nfserr_op_illegal;
1701 		}
1702 		/*
1703 		 * We'll try to cache the result in the DRC if any one
1704 		 * op in the compound wants to be cached:
1705 		 */
1706 		cachethis |= nfsd4_cache_this_op(op);
1707 
1708 		if (op->opnum == OP_READ) {
1709 			readcount++;
1710 			readbytes += nfsd4_max_reply(argp->rqstp, op);
1711 		} else
1712 			max_reply += nfsd4_max_reply(argp->rqstp, op);
1713 		/*
1714 		 * OP_LOCK may return a conflicting lock.  (Special case
1715 		 * because it will just skip encoding this if it runs
1716 		 * out of xdr buffer space, and it is the only operation
1717 		 * that behaves this way.)
1718 		 */
1719 		if (op->opnum == OP_LOCK)
1720 			max_reply += NFS4_OPAQUE_LIMIT;
1721 
1722 		if (op->status) {
1723 			argp->opcnt = i+1;
1724 			break;
1725 		}
1726 	}
1727 	/* Sessions make the DRC unnecessary: */
1728 	if (argp->minorversion)
1729 		cachethis = false;
1730 	svc_reserve(argp->rqstp, max_reply + readbytes);
1731 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1732 
1733 	if (readcount > 1 || max_reply > PAGE_SIZE - auth_slack)
1734 		clear_bit(RQ_SPLICE_OK, &argp->rqstp->rq_flags);
1735 
1736 	DECODE_TAIL;
1737 }
1738 
1739 static __be32 *encode_change(__be32 *p, struct kstat *stat, struct inode *inode)
1740 {
1741 	if (IS_I_VERSION(inode)) {
1742 		p = xdr_encode_hyper(p, inode->i_version);
1743 	} else {
1744 		*p++ = cpu_to_be32(stat->ctime.tv_sec);
1745 		*p++ = cpu_to_be32(stat->ctime.tv_nsec);
1746 	}
1747 	return p;
1748 }
1749 
1750 static __be32 *encode_cinfo(__be32 *p, struct nfsd4_change_info *c)
1751 {
1752 	*p++ = cpu_to_be32(c->atomic);
1753 	if (c->change_supported) {
1754 		p = xdr_encode_hyper(p, c->before_change);
1755 		p = xdr_encode_hyper(p, c->after_change);
1756 	} else {
1757 		*p++ = cpu_to_be32(c->before_ctime_sec);
1758 		*p++ = cpu_to_be32(c->before_ctime_nsec);
1759 		*p++ = cpu_to_be32(c->after_ctime_sec);
1760 		*p++ = cpu_to_be32(c->after_ctime_nsec);
1761 	}
1762 	return p;
1763 }
1764 
1765 /* Encode as an array of strings the string given with components
1766  * separated @sep, escaped with esc_enter and esc_exit.
1767  */
1768 static __be32 nfsd4_encode_components_esc(struct xdr_stream *xdr, char sep,
1769 					  char *components, char esc_enter,
1770 					  char esc_exit)
1771 {
1772 	__be32 *p;
1773 	__be32 pathlen;
1774 	int pathlen_offset;
1775 	int strlen, count=0;
1776 	char *str, *end, *next;
1777 
1778 	dprintk("nfsd4_encode_components(%s)\n", components);
1779 
1780 	pathlen_offset = xdr->buf->len;
1781 	p = xdr_reserve_space(xdr, 4);
1782 	if (!p)
1783 		return nfserr_resource;
1784 	p++; /* We will fill this in with @count later */
1785 
1786 	end = str = components;
1787 	while (*end) {
1788 		bool found_esc = false;
1789 
1790 		/* try to parse as esc_start, ..., esc_end, sep */
1791 		if (*str == esc_enter) {
1792 			for (; *end && (*end != esc_exit); end++)
1793 				/* find esc_exit or end of string */;
1794 			next = end + 1;
1795 			if (*end && (!*next || *next == sep)) {
1796 				str++;
1797 				found_esc = true;
1798 			}
1799 		}
1800 
1801 		if (!found_esc)
1802 			for (; *end && (*end != sep); end++)
1803 				/* find sep or end of string */;
1804 
1805 		strlen = end - str;
1806 		if (strlen) {
1807 			p = xdr_reserve_space(xdr, strlen + 4);
1808 			if (!p)
1809 				return nfserr_resource;
1810 			p = xdr_encode_opaque(p, str, strlen);
1811 			count++;
1812 		}
1813 		else
1814 			end++;
1815 		if (found_esc)
1816 			end = next;
1817 
1818 		str = end;
1819 	}
1820 	pathlen = htonl(count);
1821 	write_bytes_to_xdr_buf(xdr->buf, pathlen_offset, &pathlen, 4);
1822 	return 0;
1823 }
1824 
1825 /* Encode as an array of strings the string given with components
1826  * separated @sep.
1827  */
1828 static __be32 nfsd4_encode_components(struct xdr_stream *xdr, char sep,
1829 				      char *components)
1830 {
1831 	return nfsd4_encode_components_esc(xdr, sep, components, 0, 0);
1832 }
1833 
1834 /*
1835  * encode a location element of a fs_locations structure
1836  */
1837 static __be32 nfsd4_encode_fs_location4(struct xdr_stream *xdr,
1838 					struct nfsd4_fs_location *location)
1839 {
1840 	__be32 status;
1841 
1842 	status = nfsd4_encode_components_esc(xdr, ':', location->hosts,
1843 						'[', ']');
1844 	if (status)
1845 		return status;
1846 	status = nfsd4_encode_components(xdr, '/', location->path);
1847 	if (status)
1848 		return status;
1849 	return 0;
1850 }
1851 
1852 /*
1853  * Encode a path in RFC3530 'pathname4' format
1854  */
1855 static __be32 nfsd4_encode_path(struct xdr_stream *xdr,
1856 				const struct path *root,
1857 				const struct path *path)
1858 {
1859 	struct path cur = *path;
1860 	__be32 *p;
1861 	struct dentry **components = NULL;
1862 	unsigned int ncomponents = 0;
1863 	__be32 err = nfserr_jukebox;
1864 
1865 	dprintk("nfsd4_encode_components(");
1866 
1867 	path_get(&cur);
1868 	/* First walk the path up to the nfsd root, and store the
1869 	 * dentries/path components in an array.
1870 	 */
1871 	for (;;) {
1872 		if (cur.dentry == root->dentry && cur.mnt == root->mnt)
1873 			break;
1874 		if (cur.dentry == cur.mnt->mnt_root) {
1875 			if (follow_up(&cur))
1876 				continue;
1877 			goto out_free;
1878 		}
1879 		if ((ncomponents & 15) == 0) {
1880 			struct dentry **new;
1881 			new = krealloc(components,
1882 					sizeof(*new) * (ncomponents + 16),
1883 					GFP_KERNEL);
1884 			if (!new)
1885 				goto out_free;
1886 			components = new;
1887 		}
1888 		components[ncomponents++] = cur.dentry;
1889 		cur.dentry = dget_parent(cur.dentry);
1890 	}
1891 	err = nfserr_resource;
1892 	p = xdr_reserve_space(xdr, 4);
1893 	if (!p)
1894 		goto out_free;
1895 	*p++ = cpu_to_be32(ncomponents);
1896 
1897 	while (ncomponents) {
1898 		struct dentry *dentry = components[ncomponents - 1];
1899 		unsigned int len;
1900 
1901 		spin_lock(&dentry->d_lock);
1902 		len = dentry->d_name.len;
1903 		p = xdr_reserve_space(xdr, len + 4);
1904 		if (!p) {
1905 			spin_unlock(&dentry->d_lock);
1906 			goto out_free;
1907 		}
1908 		p = xdr_encode_opaque(p, dentry->d_name.name, len);
1909 		dprintk("/%pd", dentry);
1910 		spin_unlock(&dentry->d_lock);
1911 		dput(dentry);
1912 		ncomponents--;
1913 	}
1914 
1915 	err = 0;
1916 out_free:
1917 	dprintk(")\n");
1918 	while (ncomponents)
1919 		dput(components[--ncomponents]);
1920 	kfree(components);
1921 	path_put(&cur);
1922 	return err;
1923 }
1924 
1925 static __be32 nfsd4_encode_fsloc_fsroot(struct xdr_stream *xdr,
1926 			struct svc_rqst *rqstp, const struct path *path)
1927 {
1928 	struct svc_export *exp_ps;
1929 	__be32 res;
1930 
1931 	exp_ps = rqst_find_fsidzero_export(rqstp);
1932 	if (IS_ERR(exp_ps))
1933 		return nfserrno(PTR_ERR(exp_ps));
1934 	res = nfsd4_encode_path(xdr, &exp_ps->ex_path, path);
1935 	exp_put(exp_ps);
1936 	return res;
1937 }
1938 
1939 /*
1940  *  encode a fs_locations structure
1941  */
1942 static __be32 nfsd4_encode_fs_locations(struct xdr_stream *xdr,
1943 			struct svc_rqst *rqstp, struct svc_export *exp)
1944 {
1945 	__be32 status;
1946 	int i;
1947 	__be32 *p;
1948 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
1949 
1950 	status = nfsd4_encode_fsloc_fsroot(xdr, rqstp, &exp->ex_path);
1951 	if (status)
1952 		return status;
1953 	p = xdr_reserve_space(xdr, 4);
1954 	if (!p)
1955 		return nfserr_resource;
1956 	*p++ = cpu_to_be32(fslocs->locations_count);
1957 	for (i=0; i<fslocs->locations_count; i++) {
1958 		status = nfsd4_encode_fs_location4(xdr, &fslocs->locations[i]);
1959 		if (status)
1960 			return status;
1961 	}
1962 	return 0;
1963 }
1964 
1965 static u32 nfs4_file_type(umode_t mode)
1966 {
1967 	switch (mode & S_IFMT) {
1968 	case S_IFIFO:	return NF4FIFO;
1969 	case S_IFCHR:	return NF4CHR;
1970 	case S_IFDIR:	return NF4DIR;
1971 	case S_IFBLK:	return NF4BLK;
1972 	case S_IFLNK:	return NF4LNK;
1973 	case S_IFREG:	return NF4REG;
1974 	case S_IFSOCK:	return NF4SOCK;
1975 	default:	return NF4BAD;
1976 	};
1977 }
1978 
1979 static inline __be32
1980 nfsd4_encode_aclname(struct xdr_stream *xdr, struct svc_rqst *rqstp,
1981 		     struct nfs4_ace *ace)
1982 {
1983 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
1984 		return nfs4_acl_write_who(xdr, ace->whotype);
1985 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
1986 		return nfsd4_encode_group(xdr, rqstp, ace->who_gid);
1987 	else
1988 		return nfsd4_encode_user(xdr, rqstp, ace->who_uid);
1989 }
1990 
1991 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
1992 			      FATTR4_WORD0_RDATTR_ERROR)
1993 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
1994 
1995 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
1996 static inline __be32
1997 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
1998 			    void *context, int len)
1999 {
2000 	__be32 *p;
2001 
2002 	p = xdr_reserve_space(xdr, len + 4 + 4 + 4);
2003 	if (!p)
2004 		return nfserr_resource;
2005 
2006 	/*
2007 	 * For now we use a 0 here to indicate the null translation; in
2008 	 * the future we may place a call to translation code here.
2009 	 */
2010 	*p++ = cpu_to_be32(0); /* lfs */
2011 	*p++ = cpu_to_be32(0); /* pi */
2012 	p = xdr_encode_opaque(p, context, len);
2013 	return 0;
2014 }
2015 #else
2016 static inline __be32
2017 nfsd4_encode_security_label(struct xdr_stream *xdr, struct svc_rqst *rqstp,
2018 			    void *context, int len)
2019 { return 0; }
2020 #endif
2021 
2022 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *rdattr_err)
2023 {
2024 	/* As per referral draft:  */
2025 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2026 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2027 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2028 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2029 			*rdattr_err = NFSERR_MOVED;
2030 		else
2031 			return nfserr_moved;
2032 	}
2033 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2034 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2035 	return 0;
2036 }
2037 
2038 
2039 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2040 {
2041 	struct path path = exp->ex_path;
2042 	int err;
2043 
2044 	path_get(&path);
2045 	while (follow_up(&path)) {
2046 		if (path.dentry != path.mnt->mnt_root)
2047 			break;
2048 	}
2049 	err = vfs_getattr(&path, stat);
2050 	path_put(&path);
2051 	return err;
2052 }
2053 
2054 /*
2055  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2056  * ourselves.
2057  */
2058 static __be32
2059 nfsd4_encode_fattr(struct xdr_stream *xdr, struct svc_fh *fhp,
2060 		struct svc_export *exp,
2061 		struct dentry *dentry, u32 *bmval,
2062 		struct svc_rqst *rqstp, int ignore_crossmnt)
2063 {
2064 	u32 bmval0 = bmval[0];
2065 	u32 bmval1 = bmval[1];
2066 	u32 bmval2 = bmval[2];
2067 	struct kstat stat;
2068 	struct svc_fh *tempfh = NULL;
2069 	struct kstatfs statfs;
2070 	__be32 *p;
2071 	int starting_len = xdr->buf->len;
2072 	int attrlen_offset;
2073 	__be32 attrlen;
2074 	u32 dummy;
2075 	u64 dummy64;
2076 	u32 rdattr_err = 0;
2077 	__be32 status;
2078 	int err;
2079 	int aclsupport = 0;
2080 	struct nfs4_acl *acl = NULL;
2081 	void *context = NULL;
2082 	int contextlen;
2083 	bool contextsupport = false;
2084 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2085 	u32 minorversion = resp->cstate.minorversion;
2086 	struct path path = {
2087 		.mnt	= exp->ex_path.mnt,
2088 		.dentry	= dentry,
2089 	};
2090 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2091 
2092 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2093 	BUG_ON(bmval0 & ~nfsd_suppattrs0(minorversion));
2094 	BUG_ON(bmval1 & ~nfsd_suppattrs1(minorversion));
2095 	BUG_ON(bmval2 & ~nfsd_suppattrs2(minorversion));
2096 
2097 	if (exp->ex_fslocs.migrated) {
2098 		BUG_ON(bmval[2]);
2099 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &rdattr_err);
2100 		if (status)
2101 			goto out;
2102 	}
2103 
2104 	err = vfs_getattr(&path, &stat);
2105 	if (err)
2106 		goto out_nfserr;
2107 	if ((bmval0 & (FATTR4_WORD0_FILES_AVAIL | FATTR4_WORD0_FILES_FREE |
2108 			FATTR4_WORD0_FILES_TOTAL | FATTR4_WORD0_MAXNAME)) ||
2109 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2110 		       FATTR4_WORD1_SPACE_TOTAL))) {
2111 		err = vfs_statfs(&path, &statfs);
2112 		if (err)
2113 			goto out_nfserr;
2114 	}
2115 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2116 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2117 		status = nfserr_jukebox;
2118 		if (!tempfh)
2119 			goto out;
2120 		fh_init(tempfh, NFS4_FHSIZE);
2121 		status = fh_compose(tempfh, exp, dentry, NULL);
2122 		if (status)
2123 			goto out;
2124 		fhp = tempfh;
2125 	}
2126 	if (bmval0 & (FATTR4_WORD0_ACL | FATTR4_WORD0_ACLSUPPORT
2127 			| FATTR4_WORD0_SUPPORTED_ATTRS)) {
2128 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2129 		aclsupport = (err == 0);
2130 		if (bmval0 & FATTR4_WORD0_ACL) {
2131 			if (err == -EOPNOTSUPP)
2132 				bmval0 &= ~FATTR4_WORD0_ACL;
2133 			else if (err == -EINVAL) {
2134 				status = nfserr_attrnotsupp;
2135 				goto out;
2136 			} else if (err != 0)
2137 				goto out_nfserr;
2138 		}
2139 	}
2140 
2141 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2142 	if ((bmval[2] & FATTR4_WORD2_SECURITY_LABEL) ||
2143 			bmval[0] & FATTR4_WORD0_SUPPORTED_ATTRS) {
2144 		err = security_inode_getsecctx(dentry->d_inode,
2145 						&context, &contextlen);
2146 		contextsupport = (err == 0);
2147 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2148 			if (err == -EOPNOTSUPP)
2149 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2150 			else if (err)
2151 				goto out_nfserr;
2152 		}
2153 	}
2154 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2155 
2156 	if (bmval2) {
2157 		p = xdr_reserve_space(xdr, 16);
2158 		if (!p)
2159 			goto out_resource;
2160 		*p++ = cpu_to_be32(3);
2161 		*p++ = cpu_to_be32(bmval0);
2162 		*p++ = cpu_to_be32(bmval1);
2163 		*p++ = cpu_to_be32(bmval2);
2164 	} else if (bmval1) {
2165 		p = xdr_reserve_space(xdr, 12);
2166 		if (!p)
2167 			goto out_resource;
2168 		*p++ = cpu_to_be32(2);
2169 		*p++ = cpu_to_be32(bmval0);
2170 		*p++ = cpu_to_be32(bmval1);
2171 	} else {
2172 		p = xdr_reserve_space(xdr, 8);
2173 		if (!p)
2174 			goto out_resource;
2175 		*p++ = cpu_to_be32(1);
2176 		*p++ = cpu_to_be32(bmval0);
2177 	}
2178 
2179 	attrlen_offset = xdr->buf->len;
2180 	p = xdr_reserve_space(xdr, 4);
2181 	if (!p)
2182 		goto out_resource;
2183 	p++;                /* to be backfilled later */
2184 
2185 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2186 		u32 word0 = nfsd_suppattrs0(minorversion);
2187 		u32 word1 = nfsd_suppattrs1(minorversion);
2188 		u32 word2 = nfsd_suppattrs2(minorversion);
2189 
2190 		if (!aclsupport)
2191 			word0 &= ~FATTR4_WORD0_ACL;
2192 		if (!contextsupport)
2193 			word2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2194 		if (!word2) {
2195 			p = xdr_reserve_space(xdr, 12);
2196 			if (!p)
2197 				goto out_resource;
2198 			*p++ = cpu_to_be32(2);
2199 			*p++ = cpu_to_be32(word0);
2200 			*p++ = cpu_to_be32(word1);
2201 		} else {
2202 			p = xdr_reserve_space(xdr, 16);
2203 			if (!p)
2204 				goto out_resource;
2205 			*p++ = cpu_to_be32(3);
2206 			*p++ = cpu_to_be32(word0);
2207 			*p++ = cpu_to_be32(word1);
2208 			*p++ = cpu_to_be32(word2);
2209 		}
2210 	}
2211 	if (bmval0 & FATTR4_WORD0_TYPE) {
2212 		p = xdr_reserve_space(xdr, 4);
2213 		if (!p)
2214 			goto out_resource;
2215 		dummy = nfs4_file_type(stat.mode);
2216 		if (dummy == NF4BAD) {
2217 			status = nfserr_serverfault;
2218 			goto out;
2219 		}
2220 		*p++ = cpu_to_be32(dummy);
2221 	}
2222 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2223 		p = xdr_reserve_space(xdr, 4);
2224 		if (!p)
2225 			goto out_resource;
2226 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2227 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT);
2228 		else
2229 			*p++ = cpu_to_be32(NFS4_FH_PERSISTENT|
2230 						NFS4_FH_VOL_RENAME);
2231 	}
2232 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2233 		p = xdr_reserve_space(xdr, 8);
2234 		if (!p)
2235 			goto out_resource;
2236 		p = encode_change(p, &stat, dentry->d_inode);
2237 	}
2238 	if (bmval0 & FATTR4_WORD0_SIZE) {
2239 		p = xdr_reserve_space(xdr, 8);
2240 		if (!p)
2241 			goto out_resource;
2242 		p = xdr_encode_hyper(p, stat.size);
2243 	}
2244 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2245 		p = xdr_reserve_space(xdr, 4);
2246 		if (!p)
2247 			goto out_resource;
2248 		*p++ = cpu_to_be32(1);
2249 	}
2250 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2251 		p = xdr_reserve_space(xdr, 4);
2252 		if (!p)
2253 			goto out_resource;
2254 		*p++ = cpu_to_be32(1);
2255 	}
2256 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2257 		p = xdr_reserve_space(xdr, 4);
2258 		if (!p)
2259 			goto out_resource;
2260 		*p++ = cpu_to_be32(0);
2261 	}
2262 	if (bmval0 & FATTR4_WORD0_FSID) {
2263 		p = xdr_reserve_space(xdr, 16);
2264 		if (!p)
2265 			goto out_resource;
2266 		if (exp->ex_fslocs.migrated) {
2267 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MAJOR);
2268 			p = xdr_encode_hyper(p, NFS4_REFERRAL_FSID_MINOR);
2269 		} else switch(fsid_source(fhp)) {
2270 		case FSIDSOURCE_FSID:
2271 			p = xdr_encode_hyper(p, (u64)exp->ex_fsid);
2272 			p = xdr_encode_hyper(p, (u64)0);
2273 			break;
2274 		case FSIDSOURCE_DEV:
2275 			*p++ = cpu_to_be32(0);
2276 			*p++ = cpu_to_be32(MAJOR(stat.dev));
2277 			*p++ = cpu_to_be32(0);
2278 			*p++ = cpu_to_be32(MINOR(stat.dev));
2279 			break;
2280 		case FSIDSOURCE_UUID:
2281 			p = xdr_encode_opaque_fixed(p, exp->ex_uuid,
2282 								EX_UUID_LEN);
2283 			break;
2284 		}
2285 	}
2286 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2287 		p = xdr_reserve_space(xdr, 4);
2288 		if (!p)
2289 			goto out_resource;
2290 		*p++ = cpu_to_be32(0);
2291 	}
2292 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2293 		p = xdr_reserve_space(xdr, 4);
2294 		if (!p)
2295 			goto out_resource;
2296 		*p++ = cpu_to_be32(nn->nfsd4_lease);
2297 	}
2298 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2299 		p = xdr_reserve_space(xdr, 4);
2300 		if (!p)
2301 			goto out_resource;
2302 		*p++ = cpu_to_be32(rdattr_err);
2303 	}
2304 	if (bmval0 & FATTR4_WORD0_ACL) {
2305 		struct nfs4_ace *ace;
2306 
2307 		if (acl == NULL) {
2308 			p = xdr_reserve_space(xdr, 4);
2309 			if (!p)
2310 				goto out_resource;
2311 
2312 			*p++ = cpu_to_be32(0);
2313 			goto out_acl;
2314 		}
2315 		p = xdr_reserve_space(xdr, 4);
2316 		if (!p)
2317 			goto out_resource;
2318 		*p++ = cpu_to_be32(acl->naces);
2319 
2320 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2321 			p = xdr_reserve_space(xdr, 4*3);
2322 			if (!p)
2323 				goto out_resource;
2324 			*p++ = cpu_to_be32(ace->type);
2325 			*p++ = cpu_to_be32(ace->flag);
2326 			*p++ = cpu_to_be32(ace->access_mask &
2327 							NFS4_ACE_MASK_ALL);
2328 			status = nfsd4_encode_aclname(xdr, rqstp, ace);
2329 			if (status)
2330 				goto out;
2331 		}
2332 	}
2333 out_acl:
2334 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2335 		p = xdr_reserve_space(xdr, 4);
2336 		if (!p)
2337 			goto out_resource;
2338 		*p++ = cpu_to_be32(aclsupport ?
2339 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2340 	}
2341 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2342 		p = xdr_reserve_space(xdr, 4);
2343 		if (!p)
2344 			goto out_resource;
2345 		*p++ = cpu_to_be32(1);
2346 	}
2347 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2348 		p = xdr_reserve_space(xdr, 4);
2349 		if (!p)
2350 			goto out_resource;
2351 		*p++ = cpu_to_be32(0);
2352 	}
2353 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2354 		p = xdr_reserve_space(xdr, 4);
2355 		if (!p)
2356 			goto out_resource;
2357 		*p++ = cpu_to_be32(1);
2358 	}
2359 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2360 		p = xdr_reserve_space(xdr, 4);
2361 		if (!p)
2362 			goto out_resource;
2363 		*p++ = cpu_to_be32(1);
2364 	}
2365 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2366 		p = xdr_reserve_space(xdr, fhp->fh_handle.fh_size + 4);
2367 		if (!p)
2368 			goto out_resource;
2369 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base,
2370 					fhp->fh_handle.fh_size);
2371 	}
2372 	if (bmval0 & FATTR4_WORD0_FILEID) {
2373 		p = xdr_reserve_space(xdr, 8);
2374 		if (!p)
2375 			goto out_resource;
2376 		p = xdr_encode_hyper(p, stat.ino);
2377 	}
2378 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2379 		p = xdr_reserve_space(xdr, 8);
2380 		if (!p)
2381 			goto out_resource;
2382 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2383 	}
2384 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2385 		p = xdr_reserve_space(xdr, 8);
2386 		if (!p)
2387 			goto out_resource;
2388 		p = xdr_encode_hyper(p, (u64) statfs.f_ffree);
2389 	}
2390 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2391 		p = xdr_reserve_space(xdr, 8);
2392 		if (!p)
2393 			goto out_resource;
2394 		p = xdr_encode_hyper(p, (u64) statfs.f_files);
2395 	}
2396 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2397 		status = nfsd4_encode_fs_locations(xdr, rqstp, exp);
2398 		if (status)
2399 			goto out;
2400 	}
2401 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2402 		p = xdr_reserve_space(xdr, 4);
2403 		if (!p)
2404 			goto out_resource;
2405 		*p++ = cpu_to_be32(1);
2406 	}
2407 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2408 		p = xdr_reserve_space(xdr, 8);
2409 		if (!p)
2410 			goto out_resource;
2411 		p = xdr_encode_hyper(p, exp->ex_path.mnt->mnt_sb->s_maxbytes);
2412 	}
2413 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2414 		p = xdr_reserve_space(xdr, 4);
2415 		if (!p)
2416 			goto out_resource;
2417 		*p++ = cpu_to_be32(255);
2418 	}
2419 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2420 		p = xdr_reserve_space(xdr, 4);
2421 		if (!p)
2422 			goto out_resource;
2423 		*p++ = cpu_to_be32(statfs.f_namelen);
2424 	}
2425 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2426 		p = xdr_reserve_space(xdr, 8);
2427 		if (!p)
2428 			goto out_resource;
2429 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2430 	}
2431 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2432 		p = xdr_reserve_space(xdr, 8);
2433 		if (!p)
2434 			goto out_resource;
2435 		p = xdr_encode_hyper(p, (u64) svc_max_payload(rqstp));
2436 	}
2437 	if (bmval1 & FATTR4_WORD1_MODE) {
2438 		p = xdr_reserve_space(xdr, 4);
2439 		if (!p)
2440 			goto out_resource;
2441 		*p++ = cpu_to_be32(stat.mode & S_IALLUGO);
2442 	}
2443 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2444 		p = xdr_reserve_space(xdr, 4);
2445 		if (!p)
2446 			goto out_resource;
2447 		*p++ = cpu_to_be32(1);
2448 	}
2449 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2450 		p = xdr_reserve_space(xdr, 4);
2451 		if (!p)
2452 			goto out_resource;
2453 		*p++ = cpu_to_be32(stat.nlink);
2454 	}
2455 	if (bmval1 & FATTR4_WORD1_OWNER) {
2456 		status = nfsd4_encode_user(xdr, rqstp, stat.uid);
2457 		if (status)
2458 			goto out;
2459 	}
2460 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2461 		status = nfsd4_encode_group(xdr, rqstp, stat.gid);
2462 		if (status)
2463 			goto out;
2464 	}
2465 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2466 		p = xdr_reserve_space(xdr, 8);
2467 		if (!p)
2468 			goto out_resource;
2469 		*p++ = cpu_to_be32((u32) MAJOR(stat.rdev));
2470 		*p++ = cpu_to_be32((u32) MINOR(stat.rdev));
2471 	}
2472 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2473 		p = xdr_reserve_space(xdr, 8);
2474 		if (!p)
2475 			goto out_resource;
2476 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2477 		p = xdr_encode_hyper(p, dummy64);
2478 	}
2479 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2480 		p = xdr_reserve_space(xdr, 8);
2481 		if (!p)
2482 			goto out_resource;
2483 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2484 		p = xdr_encode_hyper(p, dummy64);
2485 	}
2486 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2487 		p = xdr_reserve_space(xdr, 8);
2488 		if (!p)
2489 			goto out_resource;
2490 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2491 		p = xdr_encode_hyper(p, dummy64);
2492 	}
2493 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2494 		p = xdr_reserve_space(xdr, 8);
2495 		if (!p)
2496 			goto out_resource;
2497 		dummy64 = (u64)stat.blocks << 9;
2498 		p = xdr_encode_hyper(p, dummy64);
2499 	}
2500 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2501 		p = xdr_reserve_space(xdr, 12);
2502 		if (!p)
2503 			goto out_resource;
2504 		p = xdr_encode_hyper(p, (s64)stat.atime.tv_sec);
2505 		*p++ = cpu_to_be32(stat.atime.tv_nsec);
2506 	}
2507 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2508 		p = xdr_reserve_space(xdr, 12);
2509 		if (!p)
2510 			goto out_resource;
2511 		*p++ = cpu_to_be32(0);
2512 		*p++ = cpu_to_be32(1);
2513 		*p++ = cpu_to_be32(0);
2514 	}
2515 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2516 		p = xdr_reserve_space(xdr, 12);
2517 		if (!p)
2518 			goto out_resource;
2519 		p = xdr_encode_hyper(p, (s64)stat.ctime.tv_sec);
2520 		*p++ = cpu_to_be32(stat.ctime.tv_nsec);
2521 	}
2522 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2523 		p = xdr_reserve_space(xdr, 12);
2524 		if (!p)
2525 			goto out_resource;
2526 		p = xdr_encode_hyper(p, (s64)stat.mtime.tv_sec);
2527 		*p++ = cpu_to_be32(stat.mtime.tv_nsec);
2528 	}
2529 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2530 		p = xdr_reserve_space(xdr, 8);
2531 		if (!p)
2532                 	goto out_resource;
2533 		/*
2534 		 * Get parent's attributes if not ignoring crossmount
2535 		 * and this is the root of a cross-mounted filesystem.
2536 		 */
2537 		if (ignore_crossmnt == 0 &&
2538 		    dentry == exp->ex_path.mnt->mnt_root)
2539 			get_parent_attributes(exp, &stat);
2540 		p = xdr_encode_hyper(p, stat.ino);
2541 	}
2542 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2543 		status = nfsd4_encode_security_label(xdr, rqstp, context,
2544 								contextlen);
2545 		if (status)
2546 			goto out;
2547 	}
2548 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2549 		p = xdr_reserve_space(xdr, 16);
2550 		if (!p)
2551 			goto out_resource;
2552 		*p++ = cpu_to_be32(3);
2553 		*p++ = cpu_to_be32(NFSD_SUPPATTR_EXCLCREAT_WORD0);
2554 		*p++ = cpu_to_be32(NFSD_SUPPATTR_EXCLCREAT_WORD1);
2555 		*p++ = cpu_to_be32(NFSD_SUPPATTR_EXCLCREAT_WORD2);
2556 	}
2557 
2558 	attrlen = htonl(xdr->buf->len - attrlen_offset - 4);
2559 	write_bytes_to_xdr_buf(xdr->buf, attrlen_offset, &attrlen, 4);
2560 	status = nfs_ok;
2561 
2562 out:
2563 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2564 	if (context)
2565 		security_release_secctx(context, contextlen);
2566 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2567 	kfree(acl);
2568 	if (tempfh) {
2569 		fh_put(tempfh);
2570 		kfree(tempfh);
2571 	}
2572 	if (status)
2573 		xdr_truncate_encode(xdr, starting_len);
2574 	return status;
2575 out_nfserr:
2576 	status = nfserrno(err);
2577 	goto out;
2578 out_resource:
2579 	status = nfserr_resource;
2580 	goto out;
2581 }
2582 
2583 static void svcxdr_init_encode_from_buffer(struct xdr_stream *xdr,
2584 				struct xdr_buf *buf, __be32 *p, int bytes)
2585 {
2586 	xdr->scratch.iov_len = 0;
2587 	memset(buf, 0, sizeof(struct xdr_buf));
2588 	buf->head[0].iov_base = p;
2589 	buf->head[0].iov_len = 0;
2590 	buf->len = 0;
2591 	xdr->buf = buf;
2592 	xdr->iov = buf->head;
2593 	xdr->p = p;
2594 	xdr->end = (void *)p + bytes;
2595 	buf->buflen = bytes;
2596 }
2597 
2598 __be32 nfsd4_encode_fattr_to_buf(__be32 **p, int words,
2599 			struct svc_fh *fhp, struct svc_export *exp,
2600 			struct dentry *dentry, u32 *bmval,
2601 			struct svc_rqst *rqstp, int ignore_crossmnt)
2602 {
2603 	struct xdr_buf dummy;
2604 	struct xdr_stream xdr;
2605 	__be32 ret;
2606 
2607 	svcxdr_init_encode_from_buffer(&xdr, &dummy, *p, words << 2);
2608 	ret = nfsd4_encode_fattr(&xdr, fhp, exp, dentry, bmval, rqstp,
2609 							ignore_crossmnt);
2610 	*p = xdr.p;
2611 	return ret;
2612 }
2613 
2614 static inline int attributes_need_mount(u32 *bmval)
2615 {
2616 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2617 		return 1;
2618 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2619 		return 1;
2620 	return 0;
2621 }
2622 
2623 static __be32
2624 nfsd4_encode_dirent_fattr(struct xdr_stream *xdr, struct nfsd4_readdir *cd,
2625 			const char *name, int namlen)
2626 {
2627 	struct svc_export *exp = cd->rd_fhp->fh_export;
2628 	struct dentry *dentry;
2629 	__be32 nfserr;
2630 	int ignore_crossmnt = 0;
2631 
2632 	dentry = lookup_one_len(name, cd->rd_fhp->fh_dentry, namlen);
2633 	if (IS_ERR(dentry))
2634 		return nfserrno(PTR_ERR(dentry));
2635 	if (!dentry->d_inode) {
2636 		/*
2637 		 * nfsd_buffered_readdir drops the i_mutex between
2638 		 * readdir and calling this callback, leaving a window
2639 		 * where this directory entry could have gone away.
2640 		 */
2641 		dput(dentry);
2642 		return nfserr_noent;
2643 	}
2644 
2645 	exp_get(exp);
2646 	/*
2647 	 * In the case of a mountpoint, the client may be asking for
2648 	 * attributes that are only properties of the underlying filesystem
2649 	 * as opposed to the cross-mounted file system. In such a case,
2650 	 * we will not follow the cross mount and will fill the attribtutes
2651 	 * directly from the mountpoint dentry.
2652 	 */
2653 	if (nfsd_mountpoint(dentry, exp)) {
2654 		int err;
2655 
2656 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
2657 				&& !attributes_need_mount(cd->rd_bmval)) {
2658 			ignore_crossmnt = 1;
2659 			goto out_encode;
2660 		}
2661 		/*
2662 		 * Why the heck aren't we just using nfsd_lookup??
2663 		 * Different "."/".." handling?  Something else?
2664 		 * At least, add a comment here to explain....
2665 		 */
2666 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
2667 		if (err) {
2668 			nfserr = nfserrno(err);
2669 			goto out_put;
2670 		}
2671 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
2672 		if (nfserr)
2673 			goto out_put;
2674 
2675 	}
2676 out_encode:
2677 	nfserr = nfsd4_encode_fattr(xdr, NULL, exp, dentry, cd->rd_bmval,
2678 					cd->rd_rqstp, ignore_crossmnt);
2679 out_put:
2680 	dput(dentry);
2681 	exp_put(exp);
2682 	return nfserr;
2683 }
2684 
2685 static __be32 *
2686 nfsd4_encode_rdattr_error(struct xdr_stream *xdr, __be32 nfserr)
2687 {
2688 	__be32 *p;
2689 
2690 	p = xdr_reserve_space(xdr, 20);
2691 	if (!p)
2692 		return NULL;
2693 	*p++ = htonl(2);
2694 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
2695 	*p++ = htonl(0);			 /* bmval1 */
2696 
2697 	*p++ = htonl(4);     /* attribute length */
2698 	*p++ = nfserr;       /* no htonl */
2699 	return p;
2700 }
2701 
2702 static int
2703 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
2704 		    loff_t offset, u64 ino, unsigned int d_type)
2705 {
2706 	struct readdir_cd *ccd = ccdv;
2707 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
2708 	struct xdr_stream *xdr = cd->xdr;
2709 	int start_offset = xdr->buf->len;
2710 	int cookie_offset;
2711 	u32 name_and_cookie;
2712 	int entry_bytes;
2713 	__be32 nfserr = nfserr_toosmall;
2714 	__be64 wire_offset;
2715 	__be32 *p;
2716 
2717 	/* In nfsv4, "." and ".." never make it onto the wire.. */
2718 	if (name && isdotent(name, namlen)) {
2719 		cd->common.err = nfs_ok;
2720 		return 0;
2721 	}
2722 
2723 	if (cd->cookie_offset) {
2724 		wire_offset = cpu_to_be64(offset);
2725 		write_bytes_to_xdr_buf(xdr->buf, cd->cookie_offset,
2726 							&wire_offset, 8);
2727 	}
2728 
2729 	p = xdr_reserve_space(xdr, 4);
2730 	if (!p)
2731 		goto fail;
2732 	*p++ = xdr_one;                             /* mark entry present */
2733 	cookie_offset = xdr->buf->len;
2734 	p = xdr_reserve_space(xdr, 3*4 + namlen);
2735 	if (!p)
2736 		goto fail;
2737 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
2738 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
2739 
2740 	nfserr = nfsd4_encode_dirent_fattr(xdr, cd, name, namlen);
2741 	switch (nfserr) {
2742 	case nfs_ok:
2743 		break;
2744 	case nfserr_resource:
2745 		nfserr = nfserr_toosmall;
2746 		goto fail;
2747 	case nfserr_noent:
2748 		xdr_truncate_encode(xdr, start_offset);
2749 		goto skip_entry;
2750 	default:
2751 		/*
2752 		 * If the client requested the RDATTR_ERROR attribute,
2753 		 * we stuff the error code into this attribute
2754 		 * and continue.  If this attribute was not requested,
2755 		 * then in accordance with the spec, we fail the
2756 		 * entire READDIR operation(!)
2757 		 */
2758 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
2759 			goto fail;
2760 		p = nfsd4_encode_rdattr_error(xdr, nfserr);
2761 		if (p == NULL) {
2762 			nfserr = nfserr_toosmall;
2763 			goto fail;
2764 		}
2765 	}
2766 	nfserr = nfserr_toosmall;
2767 	entry_bytes = xdr->buf->len - start_offset;
2768 	if (entry_bytes > cd->rd_maxcount)
2769 		goto fail;
2770 	cd->rd_maxcount -= entry_bytes;
2771 	if (!cd->rd_dircount)
2772 		goto fail;
2773 	/*
2774 	 * RFC 3530 14.2.24 describes rd_dircount as only a "hint", so
2775 	 * let's always let through the first entry, at least:
2776 	 */
2777 	name_and_cookie = 4 * XDR_QUADLEN(namlen) + 8;
2778 	if (name_and_cookie > cd->rd_dircount && cd->cookie_offset)
2779 		goto fail;
2780 	cd->rd_dircount -= min(cd->rd_dircount, name_and_cookie);
2781 	cd->cookie_offset = cookie_offset;
2782 skip_entry:
2783 	cd->common.err = nfs_ok;
2784 	return 0;
2785 fail:
2786 	xdr_truncate_encode(xdr, start_offset);
2787 	cd->common.err = nfserr;
2788 	return -EINVAL;
2789 }
2790 
2791 static __be32
2792 nfsd4_encode_stateid(struct xdr_stream *xdr, stateid_t *sid)
2793 {
2794 	__be32 *p;
2795 
2796 	p = xdr_reserve_space(xdr, sizeof(stateid_t));
2797 	if (!p)
2798 		return nfserr_resource;
2799 	*p++ = cpu_to_be32(sid->si_generation);
2800 	p = xdr_encode_opaque_fixed(p, &sid->si_opaque,
2801 					sizeof(stateid_opaque_t));
2802 	return 0;
2803 }
2804 
2805 static __be32
2806 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
2807 {
2808 	struct xdr_stream *xdr = &resp->xdr;
2809 	__be32 *p;
2810 
2811 	if (!nfserr) {
2812 		p = xdr_reserve_space(xdr, 8);
2813 		if (!p)
2814 			return nfserr_resource;
2815 		*p++ = cpu_to_be32(access->ac_supported);
2816 		*p++ = cpu_to_be32(access->ac_resp_access);
2817 	}
2818 	return nfserr;
2819 }
2820 
2821 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
2822 {
2823 	struct xdr_stream *xdr = &resp->xdr;
2824 	__be32 *p;
2825 
2826 	if (!nfserr) {
2827 		p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 8);
2828 		if (!p)
2829 			return nfserr_resource;
2830 		p = xdr_encode_opaque_fixed(p, bcts->sessionid.data,
2831 						NFS4_MAX_SESSIONID_LEN);
2832 		*p++ = cpu_to_be32(bcts->dir);
2833 		/* Sorry, we do not yet support RDMA over 4.1: */
2834 		*p++ = cpu_to_be32(0);
2835 	}
2836 	return nfserr;
2837 }
2838 
2839 static __be32
2840 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
2841 {
2842 	struct xdr_stream *xdr = &resp->xdr;
2843 
2844 	if (!nfserr)
2845 		nfserr = nfsd4_encode_stateid(xdr, &close->cl_stateid);
2846 
2847 	return nfserr;
2848 }
2849 
2850 
2851 static __be32
2852 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
2853 {
2854 	struct xdr_stream *xdr = &resp->xdr;
2855 	__be32 *p;
2856 
2857 	if (!nfserr) {
2858 		p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
2859 		if (!p)
2860 			return nfserr_resource;
2861 		p = xdr_encode_opaque_fixed(p, commit->co_verf.data,
2862 						NFS4_VERIFIER_SIZE);
2863 	}
2864 	return nfserr;
2865 }
2866 
2867 static __be32
2868 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
2869 {
2870 	struct xdr_stream *xdr = &resp->xdr;
2871 	__be32 *p;
2872 
2873 	if (!nfserr) {
2874 		p = xdr_reserve_space(xdr, 32);
2875 		if (!p)
2876 			return nfserr_resource;
2877 		p = encode_cinfo(p, &create->cr_cinfo);
2878 		*p++ = cpu_to_be32(2);
2879 		*p++ = cpu_to_be32(create->cr_bmval[0]);
2880 		*p++ = cpu_to_be32(create->cr_bmval[1]);
2881 	}
2882 	return nfserr;
2883 }
2884 
2885 static __be32
2886 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
2887 {
2888 	struct svc_fh *fhp = getattr->ga_fhp;
2889 	struct xdr_stream *xdr = &resp->xdr;
2890 
2891 	if (nfserr)
2892 		return nfserr;
2893 
2894 	nfserr = nfsd4_encode_fattr(xdr, fhp, fhp->fh_export, fhp->fh_dentry,
2895 				    getattr->ga_bmval,
2896 				    resp->rqstp, 0);
2897 	return nfserr;
2898 }
2899 
2900 static __be32
2901 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
2902 {
2903 	struct xdr_stream *xdr = &resp->xdr;
2904 	struct svc_fh *fhp = *fhpp;
2905 	unsigned int len;
2906 	__be32 *p;
2907 
2908 	if (!nfserr) {
2909 		len = fhp->fh_handle.fh_size;
2910 		p = xdr_reserve_space(xdr, len + 4);
2911 		if (!p)
2912 			return nfserr_resource;
2913 		p = xdr_encode_opaque(p, &fhp->fh_handle.fh_base, len);
2914 	}
2915 	return nfserr;
2916 }
2917 
2918 /*
2919 * Including all fields other than the name, a LOCK4denied structure requires
2920 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
2921 */
2922 static __be32
2923 nfsd4_encode_lock_denied(struct xdr_stream *xdr, struct nfsd4_lock_denied *ld)
2924 {
2925 	struct xdr_netobj *conf = &ld->ld_owner;
2926 	__be32 *p;
2927 
2928 again:
2929 	p = xdr_reserve_space(xdr, 32 + XDR_LEN(conf->len));
2930 	if (!p) {
2931 		/*
2932 		 * Don't fail to return the result just because we can't
2933 		 * return the conflicting open:
2934 		 */
2935 		if (conf->len) {
2936 			kfree(conf->data);
2937 			conf->len = 0;
2938 			conf->data = NULL;
2939 			goto again;
2940 		}
2941 		return nfserr_resource;
2942 	}
2943 	p = xdr_encode_hyper(p, ld->ld_start);
2944 	p = xdr_encode_hyper(p, ld->ld_length);
2945 	*p++ = cpu_to_be32(ld->ld_type);
2946 	if (conf->len) {
2947 		p = xdr_encode_opaque_fixed(p, &ld->ld_clientid, 8);
2948 		p = xdr_encode_opaque(p, conf->data, conf->len);
2949 		kfree(conf->data);
2950 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
2951 		p = xdr_encode_hyper(p, (u64)0); /* clientid */
2952 		*p++ = cpu_to_be32(0); /* length of owner name */
2953 	}
2954 	return nfserr_denied;
2955 }
2956 
2957 static __be32
2958 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
2959 {
2960 	struct xdr_stream *xdr = &resp->xdr;
2961 
2962 	if (!nfserr)
2963 		nfserr = nfsd4_encode_stateid(xdr, &lock->lk_resp_stateid);
2964 	else if (nfserr == nfserr_denied)
2965 		nfserr = nfsd4_encode_lock_denied(xdr, &lock->lk_denied);
2966 
2967 	return nfserr;
2968 }
2969 
2970 static __be32
2971 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
2972 {
2973 	struct xdr_stream *xdr = &resp->xdr;
2974 
2975 	if (nfserr == nfserr_denied)
2976 		nfsd4_encode_lock_denied(xdr, &lockt->lt_denied);
2977 	return nfserr;
2978 }
2979 
2980 static __be32
2981 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
2982 {
2983 	struct xdr_stream *xdr = &resp->xdr;
2984 
2985 	if (!nfserr)
2986 		nfserr = nfsd4_encode_stateid(xdr, &locku->lu_stateid);
2987 
2988 	return nfserr;
2989 }
2990 
2991 
2992 static __be32
2993 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
2994 {
2995 	struct xdr_stream *xdr = &resp->xdr;
2996 	__be32 *p;
2997 
2998 	if (!nfserr) {
2999 		p = xdr_reserve_space(xdr, 20);
3000 		if (!p)
3001 			return nfserr_resource;
3002 		p = encode_cinfo(p, &link->li_cinfo);
3003 	}
3004 	return nfserr;
3005 }
3006 
3007 
3008 static __be32
3009 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
3010 {
3011 	struct xdr_stream *xdr = &resp->xdr;
3012 	__be32 *p;
3013 
3014 	if (nfserr)
3015 		goto out;
3016 
3017 	nfserr = nfsd4_encode_stateid(xdr, &open->op_stateid);
3018 	if (nfserr)
3019 		goto out;
3020 	p = xdr_reserve_space(xdr, 40);
3021 	if (!p)
3022 		return nfserr_resource;
3023 	p = encode_cinfo(p, &open->op_cinfo);
3024 	*p++ = cpu_to_be32(open->op_rflags);
3025 	*p++ = cpu_to_be32(2);
3026 	*p++ = cpu_to_be32(open->op_bmval[0]);
3027 	*p++ = cpu_to_be32(open->op_bmval[1]);
3028 	*p++ = cpu_to_be32(open->op_delegate_type);
3029 
3030 	switch (open->op_delegate_type) {
3031 	case NFS4_OPEN_DELEGATE_NONE:
3032 		break;
3033 	case NFS4_OPEN_DELEGATE_READ:
3034 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3035 		if (nfserr)
3036 			return nfserr;
3037 		p = xdr_reserve_space(xdr, 20);
3038 		if (!p)
3039 			return nfserr_resource;
3040 		*p++ = cpu_to_be32(open->op_recall);
3041 
3042 		/*
3043 		 * TODO: ACE's in delegations
3044 		 */
3045 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3046 		*p++ = cpu_to_be32(0);
3047 		*p++ = cpu_to_be32(0);
3048 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3049 		break;
3050 	case NFS4_OPEN_DELEGATE_WRITE:
3051 		nfserr = nfsd4_encode_stateid(xdr, &open->op_delegate_stateid);
3052 		if (nfserr)
3053 			return nfserr;
3054 		p = xdr_reserve_space(xdr, 32);
3055 		if (!p)
3056 			return nfserr_resource;
3057 		*p++ = cpu_to_be32(0);
3058 
3059 		/*
3060 		 * TODO: space_limit's in delegations
3061 		 */
3062 		*p++ = cpu_to_be32(NFS4_LIMIT_SIZE);
3063 		*p++ = cpu_to_be32(~(u32)0);
3064 		*p++ = cpu_to_be32(~(u32)0);
3065 
3066 		/*
3067 		 * TODO: ACE's in delegations
3068 		 */
3069 		*p++ = cpu_to_be32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
3070 		*p++ = cpu_to_be32(0);
3071 		*p++ = cpu_to_be32(0);
3072 		*p++ = cpu_to_be32(0);   /* XXX: is NULL principal ok? */
3073 		break;
3074 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
3075 		switch (open->op_why_no_deleg) {
3076 		case WND4_CONTENTION:
3077 		case WND4_RESOURCE:
3078 			p = xdr_reserve_space(xdr, 8);
3079 			if (!p)
3080 				return nfserr_resource;
3081 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3082 			/* deleg signaling not supported yet: */
3083 			*p++ = cpu_to_be32(0);
3084 			break;
3085 		default:
3086 			p = xdr_reserve_space(xdr, 4);
3087 			if (!p)
3088 				return nfserr_resource;
3089 			*p++ = cpu_to_be32(open->op_why_no_deleg);
3090 		}
3091 		break;
3092 	default:
3093 		BUG();
3094 	}
3095 	/* XXX save filehandle here */
3096 out:
3097 	return nfserr;
3098 }
3099 
3100 static __be32
3101 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
3102 {
3103 	struct xdr_stream *xdr = &resp->xdr;
3104 
3105 	if (!nfserr)
3106 		nfserr = nfsd4_encode_stateid(xdr, &oc->oc_resp_stateid);
3107 
3108 	return nfserr;
3109 }
3110 
3111 static __be32
3112 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
3113 {
3114 	struct xdr_stream *xdr = &resp->xdr;
3115 
3116 	if (!nfserr)
3117 		nfserr = nfsd4_encode_stateid(xdr, &od->od_stateid);
3118 
3119 	return nfserr;
3120 }
3121 
3122 static __be32 nfsd4_encode_splice_read(
3123 				struct nfsd4_compoundres *resp,
3124 				struct nfsd4_read *read,
3125 				struct file *file, unsigned long maxcount)
3126 {
3127 	struct xdr_stream *xdr = &resp->xdr;
3128 	struct xdr_buf *buf = xdr->buf;
3129 	u32 eof;
3130 	int space_left;
3131 	__be32 nfserr;
3132 	__be32 *p = xdr->p - 2;
3133 
3134 	/* Make sure there will be room for padding if needed */
3135 	if (xdr->end - xdr->p < 1)
3136 		return nfserr_resource;
3137 
3138 	nfserr = nfsd_splice_read(read->rd_rqstp, file,
3139 				  read->rd_offset, &maxcount);
3140 	if (nfserr) {
3141 		/*
3142 		 * nfsd_splice_actor may have already messed with the
3143 		 * page length; reset it so as not to confuse
3144 		 * xdr_truncate_encode:
3145 		 */
3146 		buf->page_len = 0;
3147 		return nfserr;
3148 	}
3149 
3150 	eof = (read->rd_offset + maxcount >=
3151 	       read->rd_fhp->fh_dentry->d_inode->i_size);
3152 
3153 	*(p++) = htonl(eof);
3154 	*(p++) = htonl(maxcount);
3155 
3156 	buf->page_len = maxcount;
3157 	buf->len += maxcount;
3158 	xdr->page_ptr += (buf->page_base + maxcount + PAGE_SIZE - 1)
3159 							/ PAGE_SIZE;
3160 
3161 	/* Use rest of head for padding and remaining ops: */
3162 	buf->tail[0].iov_base = xdr->p;
3163 	buf->tail[0].iov_len = 0;
3164 	xdr->iov = buf->tail;
3165 	if (maxcount&3) {
3166 		int pad = 4 - (maxcount&3);
3167 
3168 		*(xdr->p++) = 0;
3169 
3170 		buf->tail[0].iov_base += maxcount&3;
3171 		buf->tail[0].iov_len = pad;
3172 		buf->len += pad;
3173 	}
3174 
3175 	space_left = min_t(int, (void *)xdr->end - (void *)xdr->p,
3176 				buf->buflen - buf->len);
3177 	buf->buflen = buf->len + space_left;
3178 	xdr->end = (__be32 *)((void *)xdr->end + space_left);
3179 
3180 	return 0;
3181 }
3182 
3183 static __be32 nfsd4_encode_readv(struct nfsd4_compoundres *resp,
3184 				 struct nfsd4_read *read,
3185 				 struct file *file, unsigned long maxcount)
3186 {
3187 	struct xdr_stream *xdr = &resp->xdr;
3188 	u32 eof;
3189 	int v;
3190 	int starting_len = xdr->buf->len - 8;
3191 	long len;
3192 	int thislen;
3193 	__be32 nfserr;
3194 	__be32 tmp;
3195 	__be32 *p;
3196 	u32 zzz = 0;
3197 	int pad;
3198 
3199 	len = maxcount;
3200 	v = 0;
3201 
3202 	thislen = min_t(long, len, ((void *)xdr->end - (void *)xdr->p));
3203 	p = xdr_reserve_space(xdr, (thislen+3)&~3);
3204 	WARN_ON_ONCE(!p);
3205 	resp->rqstp->rq_vec[v].iov_base = p;
3206 	resp->rqstp->rq_vec[v].iov_len = thislen;
3207 	v++;
3208 	len -= thislen;
3209 
3210 	while (len) {
3211 		thislen = min_t(long, len, PAGE_SIZE);
3212 		p = xdr_reserve_space(xdr, (thislen+3)&~3);
3213 		WARN_ON_ONCE(!p);
3214 		resp->rqstp->rq_vec[v].iov_base = p;
3215 		resp->rqstp->rq_vec[v].iov_len = thislen;
3216 		v++;
3217 		len -= thislen;
3218 	}
3219 	read->rd_vlen = v;
3220 
3221 	nfserr = nfsd_readv(file, read->rd_offset, resp->rqstp->rq_vec,
3222 			read->rd_vlen, &maxcount);
3223 	if (nfserr)
3224 		return nfserr;
3225 	xdr_truncate_encode(xdr, starting_len + 8 + ((maxcount+3)&~3));
3226 
3227 	eof = (read->rd_offset + maxcount >=
3228 	       read->rd_fhp->fh_dentry->d_inode->i_size);
3229 
3230 	tmp = htonl(eof);
3231 	write_bytes_to_xdr_buf(xdr->buf, starting_len    , &tmp, 4);
3232 	tmp = htonl(maxcount);
3233 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 4, &tmp, 4);
3234 
3235 	pad = (maxcount&3) ? 4 - (maxcount&3) : 0;
3236 	write_bytes_to_xdr_buf(xdr->buf, starting_len + 8 + maxcount,
3237 								&zzz, pad);
3238 	return 0;
3239 
3240 }
3241 
3242 static __be32
3243 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
3244 		  struct nfsd4_read *read)
3245 {
3246 	unsigned long maxcount;
3247 	struct xdr_stream *xdr = &resp->xdr;
3248 	struct file *file = read->rd_filp;
3249 	int starting_len = xdr->buf->len;
3250 	struct raparms *ra;
3251 	__be32 *p;
3252 	__be32 err;
3253 
3254 	if (nfserr)
3255 		return nfserr;
3256 
3257 	p = xdr_reserve_space(xdr, 8); /* eof flag and byte count */
3258 	if (!p) {
3259 		WARN_ON_ONCE(test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags));
3260 		return nfserr_resource;
3261 	}
3262 	if (resp->xdr.buf->page_len && test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags)) {
3263 		WARN_ON_ONCE(1);
3264 		return nfserr_resource;
3265 	}
3266 	xdr_commit_encode(xdr);
3267 
3268 	maxcount = svc_max_payload(resp->rqstp);
3269 	maxcount = min_t(unsigned long, maxcount, (xdr->buf->buflen - xdr->buf->len));
3270 	maxcount = min_t(unsigned long, maxcount, read->rd_length);
3271 
3272 	if (!read->rd_filp) {
3273 		err = nfsd_get_tmp_read_open(resp->rqstp, read->rd_fhp,
3274 						&file, &ra);
3275 		if (err)
3276 			goto err_truncate;
3277 	}
3278 
3279 	if (file->f_op->splice_read && test_bit(RQ_SPLICE_OK, &resp->rqstp->rq_flags))
3280 		err = nfsd4_encode_splice_read(resp, read, file, maxcount);
3281 	else
3282 		err = nfsd4_encode_readv(resp, read, file, maxcount);
3283 
3284 	if (!read->rd_filp)
3285 		nfsd_put_tmp_read_open(file, ra);
3286 
3287 err_truncate:
3288 	if (err)
3289 		xdr_truncate_encode(xdr, starting_len);
3290 	return err;
3291 }
3292 
3293 static __be32
3294 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3295 {
3296 	int maxcount;
3297 	__be32 wire_count;
3298 	int zero = 0;
3299 	struct xdr_stream *xdr = &resp->xdr;
3300 	int length_offset = xdr->buf->len;
3301 	__be32 *p;
3302 
3303 	if (nfserr)
3304 		return nfserr;
3305 
3306 	p = xdr_reserve_space(xdr, 4);
3307 	if (!p)
3308 		return nfserr_resource;
3309 	maxcount = PAGE_SIZE;
3310 
3311 	p = xdr_reserve_space(xdr, maxcount);
3312 	if (!p)
3313 		return nfserr_resource;
3314 	/*
3315 	 * XXX: By default, the ->readlink() VFS op will truncate symlinks
3316 	 * if they would overflow the buffer.  Is this kosher in NFSv4?  If
3317 	 * not, one easy fix is: if ->readlink() precisely fills the buffer,
3318 	 * assume that truncation occurred, and return NFS4ERR_RESOURCE.
3319 	 */
3320 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp,
3321 						(char *)p, &maxcount);
3322 	if (nfserr == nfserr_isdir)
3323 		nfserr = nfserr_inval;
3324 	if (nfserr) {
3325 		xdr_truncate_encode(xdr, length_offset);
3326 		return nfserr;
3327 	}
3328 
3329 	wire_count = htonl(maxcount);
3330 	write_bytes_to_xdr_buf(xdr->buf, length_offset, &wire_count, 4);
3331 	xdr_truncate_encode(xdr, length_offset + 4 + ALIGN(maxcount, 4));
3332 	if (maxcount & 3)
3333 		write_bytes_to_xdr_buf(xdr->buf, length_offset + 4 + maxcount,
3334 						&zero, 4 - (maxcount&3));
3335 	return 0;
3336 }
3337 
3338 static __be32
3339 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3340 {
3341 	int maxcount;
3342 	int bytes_left;
3343 	loff_t offset;
3344 	__be64 wire_offset;
3345 	struct xdr_stream *xdr = &resp->xdr;
3346 	int starting_len = xdr->buf->len;
3347 	__be32 *p;
3348 
3349 	if (nfserr)
3350 		return nfserr;
3351 
3352 	p = xdr_reserve_space(xdr, NFS4_VERIFIER_SIZE);
3353 	if (!p)
3354 		return nfserr_resource;
3355 
3356 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3357 	*p++ = cpu_to_be32(0);
3358 	*p++ = cpu_to_be32(0);
3359 	resp->xdr.buf->head[0].iov_len = ((char *)resp->xdr.p)
3360 				- (char *)resp->xdr.buf->head[0].iov_base;
3361 
3362 	/*
3363 	 * Number of bytes left for directory entries allowing for the
3364 	 * final 8 bytes of the readdir and a following failed op:
3365 	 */
3366 	bytes_left = xdr->buf->buflen - xdr->buf->len
3367 			- COMPOUND_ERR_SLACK_SPACE - 8;
3368 	if (bytes_left < 0) {
3369 		nfserr = nfserr_resource;
3370 		goto err_no_verf;
3371 	}
3372 	maxcount = min_t(u32, readdir->rd_maxcount, INT_MAX);
3373 	/*
3374 	 * Note the rfc defines rd_maxcount as the size of the
3375 	 * READDIR4resok structure, which includes the verifier above
3376 	 * and the 8 bytes encoded at the end of this function:
3377 	 */
3378 	if (maxcount < 16) {
3379 		nfserr = nfserr_toosmall;
3380 		goto err_no_verf;
3381 	}
3382 	maxcount = min_t(int, maxcount-16, bytes_left);
3383 
3384 	/* RFC 3530 14.2.24 allows us to ignore dircount when it's 0: */
3385 	if (!readdir->rd_dircount)
3386 		readdir->rd_dircount = INT_MAX;
3387 
3388 	readdir->xdr = xdr;
3389 	readdir->rd_maxcount = maxcount;
3390 	readdir->common.err = 0;
3391 	readdir->cookie_offset = 0;
3392 
3393 	offset = readdir->rd_cookie;
3394 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3395 			      &offset,
3396 			      &readdir->common, nfsd4_encode_dirent);
3397 	if (nfserr == nfs_ok &&
3398 	    readdir->common.err == nfserr_toosmall &&
3399 	    xdr->buf->len == starting_len + 8) {
3400 		/* nothing encoded; which limit did we hit?: */
3401 		if (maxcount - 16 < bytes_left)
3402 			/* It was the fault of rd_maxcount: */
3403 			nfserr = nfserr_toosmall;
3404 		else
3405 			/* We ran out of buffer space: */
3406 			nfserr = nfserr_resource;
3407 	}
3408 	if (nfserr)
3409 		goto err_no_verf;
3410 
3411 	if (readdir->cookie_offset) {
3412 		wire_offset = cpu_to_be64(offset);
3413 		write_bytes_to_xdr_buf(xdr->buf, readdir->cookie_offset,
3414 							&wire_offset, 8);
3415 	}
3416 
3417 	p = xdr_reserve_space(xdr, 8);
3418 	if (!p) {
3419 		WARN_ON_ONCE(1);
3420 		goto err_no_verf;
3421 	}
3422 	*p++ = 0;	/* no more entries */
3423 	*p++ = htonl(readdir->common.err == nfserr_eof);
3424 
3425 	return 0;
3426 err_no_verf:
3427 	xdr_truncate_encode(xdr, starting_len);
3428 	return nfserr;
3429 }
3430 
3431 static __be32
3432 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3433 {
3434 	struct xdr_stream *xdr = &resp->xdr;
3435 	__be32 *p;
3436 
3437 	if (!nfserr) {
3438 		p = xdr_reserve_space(xdr, 20);
3439 		if (!p)
3440 			return nfserr_resource;
3441 		p = encode_cinfo(p, &remove->rm_cinfo);
3442 	}
3443 	return nfserr;
3444 }
3445 
3446 static __be32
3447 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3448 {
3449 	struct xdr_stream *xdr = &resp->xdr;
3450 	__be32 *p;
3451 
3452 	if (!nfserr) {
3453 		p = xdr_reserve_space(xdr, 40);
3454 		if (!p)
3455 			return nfserr_resource;
3456 		p = encode_cinfo(p, &rename->rn_sinfo);
3457 		p = encode_cinfo(p, &rename->rn_tinfo);
3458 	}
3459 	return nfserr;
3460 }
3461 
3462 static __be32
3463 nfsd4_do_encode_secinfo(struct xdr_stream *xdr,
3464 			 __be32 nfserr, struct svc_export *exp)
3465 {
3466 	u32 i, nflavs, supported;
3467 	struct exp_flavor_info *flavs;
3468 	struct exp_flavor_info def_flavs[2];
3469 	__be32 *p, *flavorsp;
3470 	static bool report = true;
3471 
3472 	if (nfserr)
3473 		goto out;
3474 	nfserr = nfserr_resource;
3475 	if (exp->ex_nflavors) {
3476 		flavs = exp->ex_flavors;
3477 		nflavs = exp->ex_nflavors;
3478 	} else { /* Handling of some defaults in absence of real secinfo: */
3479 		flavs = def_flavs;
3480 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3481 			nflavs = 2;
3482 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3483 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3484 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3485 			nflavs = 1;
3486 			flavs[0].pseudoflavor
3487 					= svcauth_gss_flavor(exp->ex_client);
3488 		} else {
3489 			nflavs = 1;
3490 			flavs[0].pseudoflavor
3491 					= exp->ex_client->flavour->flavour;
3492 		}
3493 	}
3494 
3495 	supported = 0;
3496 	p = xdr_reserve_space(xdr, 4);
3497 	if (!p)
3498 		goto out;
3499 	flavorsp = p++;		/* to be backfilled later */
3500 
3501 	for (i = 0; i < nflavs; i++) {
3502 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
3503 		struct rpcsec_gss_info info;
3504 
3505 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
3506 			supported++;
3507 			p = xdr_reserve_space(xdr, 4 + 4 +
3508 					      XDR_LEN(info.oid.len) + 4 + 4);
3509 			if (!p)
3510 				goto out;
3511 			*p++ = cpu_to_be32(RPC_AUTH_GSS);
3512 			p = xdr_encode_opaque(p,  info.oid.data, info.oid.len);
3513 			*p++ = cpu_to_be32(info.qop);
3514 			*p++ = cpu_to_be32(info.service);
3515 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
3516 			supported++;
3517 			p = xdr_reserve_space(xdr, 4);
3518 			if (!p)
3519 				goto out;
3520 			*p++ = cpu_to_be32(pf);
3521 		} else {
3522 			if (report)
3523 				pr_warn("NFS: SECINFO: security flavor %u "
3524 					"is not supported\n", pf);
3525 		}
3526 	}
3527 
3528 	if (nflavs != supported)
3529 		report = false;
3530 	*flavorsp = htonl(supported);
3531 	nfserr = 0;
3532 out:
3533 	if (exp)
3534 		exp_put(exp);
3535 	return nfserr;
3536 }
3537 
3538 static __be32
3539 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3540 		     struct nfsd4_secinfo *secinfo)
3541 {
3542 	struct xdr_stream *xdr = &resp->xdr;
3543 
3544 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->si_exp);
3545 }
3546 
3547 static __be32
3548 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3549 		     struct nfsd4_secinfo_no_name *secinfo)
3550 {
3551 	struct xdr_stream *xdr = &resp->xdr;
3552 
3553 	return nfsd4_do_encode_secinfo(xdr, nfserr, secinfo->sin_exp);
3554 }
3555 
3556 /*
3557  * The SETATTR encode routine is special -- it always encodes a bitmap,
3558  * regardless of the error status.
3559  */
3560 static __be32
3561 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3562 {
3563 	struct xdr_stream *xdr = &resp->xdr;
3564 	__be32 *p;
3565 
3566 	p = xdr_reserve_space(xdr, 16);
3567 	if (!p)
3568 		return nfserr_resource;
3569 	if (nfserr) {
3570 		*p++ = cpu_to_be32(3);
3571 		*p++ = cpu_to_be32(0);
3572 		*p++ = cpu_to_be32(0);
3573 		*p++ = cpu_to_be32(0);
3574 	}
3575 	else {
3576 		*p++ = cpu_to_be32(3);
3577 		*p++ = cpu_to_be32(setattr->sa_bmval[0]);
3578 		*p++ = cpu_to_be32(setattr->sa_bmval[1]);
3579 		*p++ = cpu_to_be32(setattr->sa_bmval[2]);
3580 	}
3581 	return nfserr;
3582 }
3583 
3584 static __be32
3585 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3586 {
3587 	struct xdr_stream *xdr = &resp->xdr;
3588 	__be32 *p;
3589 
3590 	if (!nfserr) {
3591 		p = xdr_reserve_space(xdr, 8 + NFS4_VERIFIER_SIZE);
3592 		if (!p)
3593 			return nfserr_resource;
3594 		p = xdr_encode_opaque_fixed(p, &scd->se_clientid, 8);
3595 		p = xdr_encode_opaque_fixed(p, &scd->se_confirm,
3596 						NFS4_VERIFIER_SIZE);
3597 	}
3598 	else if (nfserr == nfserr_clid_inuse) {
3599 		p = xdr_reserve_space(xdr, 8);
3600 		if (!p)
3601 			return nfserr_resource;
3602 		*p++ = cpu_to_be32(0);
3603 		*p++ = cpu_to_be32(0);
3604 	}
3605 	return nfserr;
3606 }
3607 
3608 static __be32
3609 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3610 {
3611 	struct xdr_stream *xdr = &resp->xdr;
3612 	__be32 *p;
3613 
3614 	if (!nfserr) {
3615 		p = xdr_reserve_space(xdr, 16);
3616 		if (!p)
3617 			return nfserr_resource;
3618 		*p++ = cpu_to_be32(write->wr_bytes_written);
3619 		*p++ = cpu_to_be32(write->wr_how_written);
3620 		p = xdr_encode_opaque_fixed(p, write->wr_verifier.data,
3621 							NFS4_VERIFIER_SIZE);
3622 	}
3623 	return nfserr;
3624 }
3625 
3626 static const u32 nfs4_minimal_spo_must_enforce[2] = {
3627 	[1] = 1 << (OP_BIND_CONN_TO_SESSION - 32) |
3628 	      1 << (OP_EXCHANGE_ID - 32) |
3629 	      1 << (OP_CREATE_SESSION - 32) |
3630 	      1 << (OP_DESTROY_SESSION - 32) |
3631 	      1 << (OP_DESTROY_CLIENTID - 32)
3632 };
3633 
3634 static __be32
3635 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
3636 			 struct nfsd4_exchange_id *exid)
3637 {
3638 	struct xdr_stream *xdr = &resp->xdr;
3639 	__be32 *p;
3640 	char *major_id;
3641 	char *server_scope;
3642 	int major_id_sz;
3643 	int server_scope_sz;
3644 	uint64_t minor_id = 0;
3645 
3646 	if (nfserr)
3647 		return nfserr;
3648 
3649 	major_id = utsname()->nodename;
3650 	major_id_sz = strlen(major_id);
3651 	server_scope = utsname()->nodename;
3652 	server_scope_sz = strlen(server_scope);
3653 
3654 	p = xdr_reserve_space(xdr,
3655 		8 /* eir_clientid */ +
3656 		4 /* eir_sequenceid */ +
3657 		4 /* eir_flags */ +
3658 		4 /* spr_how */);
3659 	if (!p)
3660 		return nfserr_resource;
3661 
3662 	p = xdr_encode_opaque_fixed(p, &exid->clientid, 8);
3663 	*p++ = cpu_to_be32(exid->seqid);
3664 	*p++ = cpu_to_be32(exid->flags);
3665 
3666 	*p++ = cpu_to_be32(exid->spa_how);
3667 
3668 	switch (exid->spa_how) {
3669 	case SP4_NONE:
3670 		break;
3671 	case SP4_MACH_CRED:
3672 		/* spo_must_enforce, spo_must_allow */
3673 		p = xdr_reserve_space(xdr, 16);
3674 		if (!p)
3675 			return nfserr_resource;
3676 
3677 		/* spo_must_enforce bitmap: */
3678 		*p++ = cpu_to_be32(2);
3679 		*p++ = cpu_to_be32(nfs4_minimal_spo_must_enforce[0]);
3680 		*p++ = cpu_to_be32(nfs4_minimal_spo_must_enforce[1]);
3681 		/* empty spo_must_allow bitmap: */
3682 		*p++ = cpu_to_be32(0);
3683 
3684 		break;
3685 	default:
3686 		WARN_ON_ONCE(1);
3687 	}
3688 
3689 	p = xdr_reserve_space(xdr,
3690 		8 /* so_minor_id */ +
3691 		4 /* so_major_id.len */ +
3692 		(XDR_QUADLEN(major_id_sz) * 4) +
3693 		4 /* eir_server_scope.len */ +
3694 		(XDR_QUADLEN(server_scope_sz) * 4) +
3695 		4 /* eir_server_impl_id.count (0) */);
3696 	if (!p)
3697 		return nfserr_resource;
3698 
3699 	/* The server_owner struct */
3700 	p = xdr_encode_hyper(p, minor_id);      /* Minor id */
3701 	/* major id */
3702 	p = xdr_encode_opaque(p, major_id, major_id_sz);
3703 
3704 	/* Server scope */
3705 	p = xdr_encode_opaque(p, server_scope, server_scope_sz);
3706 
3707 	/* Implementation id */
3708 	*p++ = cpu_to_be32(0);	/* zero length nfs_impl_id4 array */
3709 	return 0;
3710 }
3711 
3712 static __be32
3713 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
3714 			    struct nfsd4_create_session *sess)
3715 {
3716 	struct xdr_stream *xdr = &resp->xdr;
3717 	__be32 *p;
3718 
3719 	if (nfserr)
3720 		return nfserr;
3721 
3722 	p = xdr_reserve_space(xdr, 24);
3723 	if (!p)
3724 		return nfserr_resource;
3725 	p = xdr_encode_opaque_fixed(p, sess->sessionid.data,
3726 					NFS4_MAX_SESSIONID_LEN);
3727 	*p++ = cpu_to_be32(sess->seqid);
3728 	*p++ = cpu_to_be32(sess->flags);
3729 
3730 	p = xdr_reserve_space(xdr, 28);
3731 	if (!p)
3732 		return nfserr_resource;
3733 	*p++ = cpu_to_be32(0); /* headerpadsz */
3734 	*p++ = cpu_to_be32(sess->fore_channel.maxreq_sz);
3735 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_sz);
3736 	*p++ = cpu_to_be32(sess->fore_channel.maxresp_cached);
3737 	*p++ = cpu_to_be32(sess->fore_channel.maxops);
3738 	*p++ = cpu_to_be32(sess->fore_channel.maxreqs);
3739 	*p++ = cpu_to_be32(sess->fore_channel.nr_rdma_attrs);
3740 
3741 	if (sess->fore_channel.nr_rdma_attrs) {
3742 		p = xdr_reserve_space(xdr, 4);
3743 		if (!p)
3744 			return nfserr_resource;
3745 		*p++ = cpu_to_be32(sess->fore_channel.rdma_attrs);
3746 	}
3747 
3748 	p = xdr_reserve_space(xdr, 28);
3749 	if (!p)
3750 		return nfserr_resource;
3751 	*p++ = cpu_to_be32(0); /* headerpadsz */
3752 	*p++ = cpu_to_be32(sess->back_channel.maxreq_sz);
3753 	*p++ = cpu_to_be32(sess->back_channel.maxresp_sz);
3754 	*p++ = cpu_to_be32(sess->back_channel.maxresp_cached);
3755 	*p++ = cpu_to_be32(sess->back_channel.maxops);
3756 	*p++ = cpu_to_be32(sess->back_channel.maxreqs);
3757 	*p++ = cpu_to_be32(sess->back_channel.nr_rdma_attrs);
3758 
3759 	if (sess->back_channel.nr_rdma_attrs) {
3760 		p = xdr_reserve_space(xdr, 4);
3761 		if (!p)
3762 			return nfserr_resource;
3763 		*p++ = cpu_to_be32(sess->back_channel.rdma_attrs);
3764 	}
3765 	return 0;
3766 }
3767 
3768 static __be32
3769 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
3770 		      struct nfsd4_sequence *seq)
3771 {
3772 	struct xdr_stream *xdr = &resp->xdr;
3773 	__be32 *p;
3774 
3775 	if (nfserr)
3776 		return nfserr;
3777 
3778 	p = xdr_reserve_space(xdr, NFS4_MAX_SESSIONID_LEN + 20);
3779 	if (!p)
3780 		return nfserr_resource;
3781 	p = xdr_encode_opaque_fixed(p, seq->sessionid.data,
3782 					NFS4_MAX_SESSIONID_LEN);
3783 	*p++ = cpu_to_be32(seq->seqid);
3784 	*p++ = cpu_to_be32(seq->slotid);
3785 	/* Note slotid's are numbered from zero: */
3786 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_highest_slotid */
3787 	*p++ = cpu_to_be32(seq->maxslots - 1); /* sr_target_highest_slotid */
3788 	*p++ = cpu_to_be32(seq->status_flags);
3789 
3790 	resp->cstate.data_offset = xdr->buf->len; /* DRC cache data pointer */
3791 	return 0;
3792 }
3793 
3794 static __be32
3795 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
3796 			  struct nfsd4_test_stateid *test_stateid)
3797 {
3798 	struct xdr_stream *xdr = &resp->xdr;
3799 	struct nfsd4_test_stateid_id *stateid, *next;
3800 	__be32 *p;
3801 
3802 	if (nfserr)
3803 		return nfserr;
3804 
3805 	p = xdr_reserve_space(xdr, 4 + (4 * test_stateid->ts_num_ids));
3806 	if (!p)
3807 		return nfserr_resource;
3808 	*p++ = htonl(test_stateid->ts_num_ids);
3809 
3810 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
3811 		*p++ = stateid->ts_id_status;
3812 	}
3813 
3814 	return nfserr;
3815 }
3816 
3817 static __be32
3818 nfsd4_encode_seek(struct nfsd4_compoundres *resp, __be32 nfserr,
3819 		  struct nfsd4_seek *seek)
3820 {
3821 	__be32 *p;
3822 
3823 	if (nfserr)
3824 		return nfserr;
3825 
3826 	p = xdr_reserve_space(&resp->xdr, 4 + 8);
3827 	*p++ = cpu_to_be32(seek->seek_eof);
3828 	p = xdr_encode_hyper(p, seek->seek_pos);
3829 
3830 	return nfserr;
3831 }
3832 
3833 static __be32
3834 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
3835 {
3836 	return nfserr;
3837 }
3838 
3839 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
3840 
3841 /*
3842  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
3843  * since we don't need to filter out obsolete ops as this is
3844  * done in the decoding phase.
3845  */
3846 static nfsd4_enc nfsd4_enc_ops[] = {
3847 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
3848 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
3849 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
3850 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
3851 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
3852 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
3853 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
3854 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
3855 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
3856 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
3857 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
3858 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
3859 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
3860 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
3861 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
3862 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
3863 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
3864 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
3865 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
3866 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
3867 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
3868 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
3869 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
3870 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
3871 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
3872 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
3873 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
3874 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
3875 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
3876 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
3877 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
3878 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
3879 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
3880 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
3881 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
3882 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
3883 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
3884 
3885 	/* NFSv4.1 operations */
3886 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
3887 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
3888 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
3889 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
3890 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
3891 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
3892 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
3893 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
3894 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
3895 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
3896 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
3897 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
3898 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
3899 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
3900 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
3901 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
3902 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
3903 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
3904 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
3905 
3906 	/* NFSv4.2 operations */
3907 	[OP_ALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
3908 	[OP_COPY]		= (nfsd4_enc)nfsd4_encode_noop,
3909 	[OP_COPY_NOTIFY]	= (nfsd4_enc)nfsd4_encode_noop,
3910 	[OP_DEALLOCATE]		= (nfsd4_enc)nfsd4_encode_noop,
3911 	[OP_IO_ADVISE]		= (nfsd4_enc)nfsd4_encode_noop,
3912 	[OP_LAYOUTERROR]	= (nfsd4_enc)nfsd4_encode_noop,
3913 	[OP_LAYOUTSTATS]	= (nfsd4_enc)nfsd4_encode_noop,
3914 	[OP_OFFLOAD_CANCEL]	= (nfsd4_enc)nfsd4_encode_noop,
3915 	[OP_OFFLOAD_STATUS]	= (nfsd4_enc)nfsd4_encode_noop,
3916 	[OP_READ_PLUS]		= (nfsd4_enc)nfsd4_encode_noop,
3917 	[OP_SEEK]		= (nfsd4_enc)nfsd4_encode_seek,
3918 	[OP_WRITE_SAME]		= (nfsd4_enc)nfsd4_encode_noop,
3919 };
3920 
3921 /*
3922  * Calculate whether we still have space to encode repsize bytes.
3923  * There are two considerations:
3924  *     - For NFS versions >=4.1, the size of the reply must stay within
3925  *       session limits
3926  *     - For all NFS versions, we must stay within limited preallocated
3927  *       buffer space.
3928  *
3929  * This is called before the operation is processed, so can only provide
3930  * an upper estimate.  For some nonidempotent operations (such as
3931  * getattr), it's not necessarily a problem if that estimate is wrong,
3932  * as we can fail it after processing without significant side effects.
3933  */
3934 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 respsize)
3935 {
3936 	struct xdr_buf *buf = &resp->rqstp->rq_res;
3937 	struct nfsd4_slot *slot = resp->cstate.slot;
3938 
3939 	if (buf->len + respsize <= buf->buflen)
3940 		return nfs_ok;
3941 	if (!nfsd4_has_session(&resp->cstate))
3942 		return nfserr_resource;
3943 	if (slot->sl_flags & NFSD4_SLOT_CACHETHIS) {
3944 		WARN_ON_ONCE(1);
3945 		return nfserr_rep_too_big_to_cache;
3946 	}
3947 	return nfserr_rep_too_big;
3948 }
3949 
3950 void
3951 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
3952 {
3953 	struct xdr_stream *xdr = &resp->xdr;
3954 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
3955 	struct svc_rqst *rqstp = resp->rqstp;
3956 	int post_err_offset;
3957 	nfsd4_enc encoder;
3958 	__be32 *p;
3959 
3960 	p = xdr_reserve_space(xdr, 8);
3961 	if (!p) {
3962 		WARN_ON_ONCE(1);
3963 		return;
3964 	}
3965 	*p++ = cpu_to_be32(op->opnum);
3966 	post_err_offset = xdr->buf->len;
3967 
3968 	if (op->opnum == OP_ILLEGAL)
3969 		goto status;
3970 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
3971 	       !nfsd4_enc_ops[op->opnum]);
3972 	encoder = nfsd4_enc_ops[op->opnum];
3973 	op->status = encoder(resp, op->status, &op->u);
3974 	xdr_commit_encode(xdr);
3975 
3976 	/* nfsd4_check_resp_size guarantees enough room for error status */
3977 	if (!op->status) {
3978 		int space_needed = 0;
3979 		if (!nfsd4_last_compound_op(rqstp))
3980 			space_needed = COMPOUND_ERR_SLACK_SPACE;
3981 		op->status = nfsd4_check_resp_size(resp, space_needed);
3982 	}
3983 	if (op->status == nfserr_resource && nfsd4_has_session(&resp->cstate)) {
3984 		struct nfsd4_slot *slot = resp->cstate.slot;
3985 
3986 		if (slot->sl_flags & NFSD4_SLOT_CACHETHIS)
3987 			op->status = nfserr_rep_too_big_to_cache;
3988 		else
3989 			op->status = nfserr_rep_too_big;
3990 	}
3991 	if (op->status == nfserr_resource ||
3992 	    op->status == nfserr_rep_too_big ||
3993 	    op->status == nfserr_rep_too_big_to_cache) {
3994 		/*
3995 		 * The operation may have already been encoded or
3996 		 * partially encoded.  No op returns anything additional
3997 		 * in the case of one of these three errors, so we can
3998 		 * just truncate back to after the status.  But it's a
3999 		 * bug if we had to do this on a non-idempotent op:
4000 		 */
4001 		warn_on_nonidempotent_op(op);
4002 		xdr_truncate_encode(xdr, post_err_offset);
4003 	}
4004 	if (so) {
4005 		int len = xdr->buf->len - post_err_offset;
4006 
4007 		so->so_replay.rp_status = op->status;
4008 		so->so_replay.rp_buflen = len;
4009 		read_bytes_from_xdr_buf(xdr->buf, post_err_offset,
4010 						so->so_replay.rp_buf, len);
4011 	}
4012 status:
4013 	/* Note that op->status is already in network byte order: */
4014 	write_bytes_to_xdr_buf(xdr->buf, post_err_offset - 4, &op->status, 4);
4015 }
4016 
4017 /*
4018  * Encode the reply stored in the stateowner reply cache
4019  *
4020  * XDR note: do not encode rp->rp_buflen: the buffer contains the
4021  * previously sent already encoded operation.
4022  */
4023 void
4024 nfsd4_encode_replay(struct xdr_stream *xdr, struct nfsd4_op *op)
4025 {
4026 	__be32 *p;
4027 	struct nfs4_replay *rp = op->replay;
4028 
4029 	BUG_ON(!rp);
4030 
4031 	p = xdr_reserve_space(xdr, 8 + rp->rp_buflen);
4032 	if (!p) {
4033 		WARN_ON_ONCE(1);
4034 		return;
4035 	}
4036 	*p++ = cpu_to_be32(op->opnum);
4037 	*p++ = rp->rp_status;  /* already xdr'ed */
4038 
4039 	p = xdr_encode_opaque_fixed(p, rp->rp_buf, rp->rp_buflen);
4040 }
4041 
4042 int
4043 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
4044 {
4045         return xdr_ressize_check(rqstp, p);
4046 }
4047 
4048 int nfsd4_release_compoundargs(void *rq, __be32 *p, void *resp)
4049 {
4050 	struct svc_rqst *rqstp = rq;
4051 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
4052 
4053 	if (args->ops != args->iops) {
4054 		kfree(args->ops);
4055 		args->ops = args->iops;
4056 	}
4057 	kfree(args->tmpp);
4058 	args->tmpp = NULL;
4059 	while (args->to_free) {
4060 		struct svcxdr_tmpbuf *tb = args->to_free;
4061 		args->to_free = tb->next;
4062 		kfree(tb);
4063 	}
4064 	return 1;
4065 }
4066 
4067 int
4068 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundargs *args)
4069 {
4070 	if (rqstp->rq_arg.head[0].iov_len % 4) {
4071 		/* client is nuts */
4072 		dprintk("%s: compound not properly padded! (peeraddr=%pISc xid=0x%x)",
4073 			__func__, svc_addr(rqstp), be32_to_cpu(rqstp->rq_xid));
4074 		return 0;
4075 	}
4076 	args->p = p;
4077 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
4078 	args->pagelist = rqstp->rq_arg.pages;
4079 	args->pagelen = rqstp->rq_arg.page_len;
4080 	args->tmpp = NULL;
4081 	args->to_free = NULL;
4082 	args->ops = args->iops;
4083 	args->rqstp = rqstp;
4084 
4085 	return !nfsd4_decode_compound(args);
4086 }
4087 
4088 int
4089 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundres *resp)
4090 {
4091 	/*
4092 	 * All that remains is to write the tag and operation count...
4093 	 */
4094 	struct xdr_buf *buf = resp->xdr.buf;
4095 
4096 	WARN_ON_ONCE(buf->len != buf->head[0].iov_len + buf->page_len +
4097 				 buf->tail[0].iov_len);
4098 
4099 	rqstp->rq_next_page = resp->xdr.page_ptr + 1;
4100 
4101 	p = resp->tagp;
4102 	*p++ = htonl(resp->taglen);
4103 	memcpy(p, resp->tag, resp->taglen);
4104 	p += XDR_QUADLEN(resp->taglen);
4105 	*p++ = htonl(resp->opcnt);
4106 
4107 	nfsd4_sequence_done(resp);
4108 	return 1;
4109 }
4110 
4111 /*
4112  * Local variables:
4113  *  c-basic-offset: 8
4114  * End:
4115  */
4116