xref: /openbmc/linux/fs/nfsd/nfs4xdr.c (revision 8e9356c6)
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  * TODO: Neil Brown made the following observation:  We currently
36  * initially reserve NFSD_BUFSIZE space on the transmit queue and
37  * never release any of that until the request is complete.
38  * It would be good to calculate a new maximum response size while
39  * decoding the COMPOUND, and call svc_reserve with this number
40  * at the end of nfs4svc_decode_compoundargs.
41  */
42 
43 #include <linux/slab.h>
44 #include <linux/namei.h>
45 #include <linux/statfs.h>
46 #include <linux/utsname.h>
47 #include <linux/pagemap.h>
48 #include <linux/sunrpc/svcauth_gss.h>
49 
50 #include "idmap.h"
51 #include "acl.h"
52 #include "xdr4.h"
53 #include "vfs.h"
54 #include "state.h"
55 #include "cache.h"
56 #include "netns.h"
57 
58 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
59 #include <linux/security.h>
60 #endif
61 
62 
63 #define NFSDDBG_FACILITY		NFSDDBG_XDR
64 
65 /*
66  * As per referral draft, the fsid for a referral MUST be different from the fsid of the containing
67  * directory in order to indicate to the client that a filesystem boundary is present
68  * We use a fixed fsid for a referral
69  */
70 #define NFS4_REFERRAL_FSID_MAJOR	0x8000000ULL
71 #define NFS4_REFERRAL_FSID_MINOR	0x8000000ULL
72 
73 static __be32
74 check_filename(char *str, int len)
75 {
76 	int i;
77 
78 	if (len == 0)
79 		return nfserr_inval;
80 	if (isdotent(str, len))
81 		return nfserr_badname;
82 	for (i = 0; i < len; i++)
83 		if (str[i] == '/')
84 			return nfserr_badname;
85 	return 0;
86 }
87 
88 #define DECODE_HEAD				\
89 	__be32 *p;				\
90 	__be32 status
91 #define DECODE_TAIL				\
92 	status = 0;				\
93 out:						\
94 	return status;				\
95 xdr_error:					\
96 	dprintk("NFSD: xdr error (%s:%d)\n",	\
97 			__FILE__, __LINE__);	\
98 	status = nfserr_bad_xdr;		\
99 	goto out
100 
101 #define READ32(x)         (x) = ntohl(*p++)
102 #define READ64(x)         do {			\
103 	(x) = (u64)ntohl(*p++) << 32;		\
104 	(x) |= ntohl(*p++);			\
105 } while (0)
106 #define READMEM(x,nbytes) do {			\
107 	x = (char *)p;				\
108 	p += XDR_QUADLEN(nbytes);		\
109 } while (0)
110 #define SAVEMEM(x,nbytes) do {			\
111 	if (!(x = (p==argp->tmp || p == argp->tmpp) ? \
112  		savemem(argp, p, nbytes) :	\
113  		(char *)p)) {			\
114 		dprintk("NFSD: xdr error (%s:%d)\n", \
115 				__FILE__, __LINE__); \
116 		goto xdr_error;			\
117 		}				\
118 	p += XDR_QUADLEN(nbytes);		\
119 } while (0)
120 #define COPYMEM(x,nbytes) do {			\
121 	memcpy((x), p, nbytes);			\
122 	p += XDR_QUADLEN(nbytes);		\
123 } while (0)
124 
125 /* READ_BUF, read_buf(): nbytes must be <= PAGE_SIZE */
126 #define READ_BUF(nbytes)  do {			\
127 	if (nbytes <= (u32)((char *)argp->end - (char *)argp->p)) {	\
128 		p = argp->p;			\
129 		argp->p += XDR_QUADLEN(nbytes);	\
130 	} else if (!(p = read_buf(argp, nbytes))) { \
131 		dprintk("NFSD: xdr error (%s:%d)\n", \
132 				__FILE__, __LINE__); \
133 		goto xdr_error;			\
134 	}					\
135 } while (0)
136 
137 static void next_decode_page(struct nfsd4_compoundargs *argp)
138 {
139 	argp->p = page_address(argp->pagelist[0]);
140 	argp->pagelist++;
141 	if (argp->pagelen < PAGE_SIZE) {
142 		argp->end = argp->p + (argp->pagelen>>2);
143 		argp->pagelen = 0;
144 	} else {
145 		argp->end = argp->p + (PAGE_SIZE>>2);
146 		argp->pagelen -= PAGE_SIZE;
147 	}
148 }
149 
150 static __be32 *read_buf(struct nfsd4_compoundargs *argp, u32 nbytes)
151 {
152 	/* We want more bytes than seem to be available.
153 	 * Maybe we need a new page, maybe we have just run out
154 	 */
155 	unsigned int avail = (char *)argp->end - (char *)argp->p;
156 	__be32 *p;
157 	if (avail + argp->pagelen < nbytes)
158 		return NULL;
159 	if (avail + PAGE_SIZE < nbytes) /* need more than a page !! */
160 		return NULL;
161 	/* ok, we can do it with the current plus the next page */
162 	if (nbytes <= sizeof(argp->tmp))
163 		p = argp->tmp;
164 	else {
165 		kfree(argp->tmpp);
166 		p = argp->tmpp = kmalloc(nbytes, GFP_KERNEL);
167 		if (!p)
168 			return NULL;
169 
170 	}
171 	/*
172 	 * The following memcpy is safe because read_buf is always
173 	 * called with nbytes > avail, and the two cases above both
174 	 * guarantee p points to at least nbytes bytes.
175 	 */
176 	memcpy(p, argp->p, avail);
177 	next_decode_page(argp);
178 	memcpy(((char*)p)+avail, argp->p, (nbytes - avail));
179 	argp->p += XDR_QUADLEN(nbytes - avail);
180 	return p;
181 }
182 
183 static int zero_clientid(clientid_t *clid)
184 {
185 	return (clid->cl_boot == 0) && (clid->cl_id == 0);
186 }
187 
188 /**
189  * defer_free - mark an allocation as deferred freed
190  * @argp: NFSv4 compound argument structure to be freed with
191  * @release: release callback to free @p, typically kfree()
192  * @p: pointer to be freed
193  *
194  * Marks @p to be freed when processing the compound operation
195  * described in @argp finishes.
196  */
197 static int
198 defer_free(struct nfsd4_compoundargs *argp,
199 		void (*release)(const void *), void *p)
200 {
201 	struct tmpbuf *tb;
202 
203 	tb = kmalloc(sizeof(*tb), GFP_KERNEL);
204 	if (!tb)
205 		return -ENOMEM;
206 	tb->buf = p;
207 	tb->release = release;
208 	tb->next = argp->to_free;
209 	argp->to_free = tb;
210 	return 0;
211 }
212 
213 /**
214  * savemem - duplicate a chunk of memory for later processing
215  * @argp: NFSv4 compound argument structure to be freed with
216  * @p: pointer to be duplicated
217  * @nbytes: length to be duplicated
218  *
219  * Returns a pointer to a copy of @nbytes bytes of memory at @p
220  * that are preserved until processing of the NFSv4 compound
221  * operation described by @argp finishes.
222  */
223 static char *savemem(struct nfsd4_compoundargs *argp, __be32 *p, int nbytes)
224 {
225 	if (p == argp->tmp) {
226 		p = kmemdup(argp->tmp, nbytes, GFP_KERNEL);
227 		if (!p)
228 			return NULL;
229 	} else {
230 		BUG_ON(p != argp->tmpp);
231 		argp->tmpp = NULL;
232 	}
233 	if (defer_free(argp, kfree, p)) {
234 		kfree(p);
235 		return NULL;
236 	} else
237 		return (char *)p;
238 }
239 
240 static __be32
241 nfsd4_decode_bitmap(struct nfsd4_compoundargs *argp, u32 *bmval)
242 {
243 	u32 bmlen;
244 	DECODE_HEAD;
245 
246 	bmval[0] = 0;
247 	bmval[1] = 0;
248 	bmval[2] = 0;
249 
250 	READ_BUF(4);
251 	READ32(bmlen);
252 	if (bmlen > 1000)
253 		goto xdr_error;
254 
255 	READ_BUF(bmlen << 2);
256 	if (bmlen > 0)
257 		READ32(bmval[0]);
258 	if (bmlen > 1)
259 		READ32(bmval[1]);
260 	if (bmlen > 2)
261 		READ32(bmval[2]);
262 
263 	DECODE_TAIL;
264 }
265 
266 static __be32
267 nfsd4_decode_fattr(struct nfsd4_compoundargs *argp, u32 *bmval,
268 		   struct iattr *iattr, struct nfs4_acl **acl,
269 		   struct xdr_netobj *label)
270 {
271 	int expected_len, len = 0;
272 	u32 dummy32;
273 	char *buf;
274 
275 	DECODE_HEAD;
276 	iattr->ia_valid = 0;
277 	if ((status = nfsd4_decode_bitmap(argp, bmval)))
278 		return status;
279 
280 	READ_BUF(4);
281 	READ32(expected_len);
282 
283 	if (bmval[0] & FATTR4_WORD0_SIZE) {
284 		READ_BUF(8);
285 		len += 8;
286 		READ64(iattr->ia_size);
287 		iattr->ia_valid |= ATTR_SIZE;
288 	}
289 	if (bmval[0] & FATTR4_WORD0_ACL) {
290 		u32 nace;
291 		struct nfs4_ace *ace;
292 
293 		READ_BUF(4); len += 4;
294 		READ32(nace);
295 
296 		if (nace > NFS4_ACL_MAX)
297 			return nfserr_resource;
298 
299 		*acl = nfs4_acl_new(nace);
300 		if (*acl == NULL)
301 			return nfserr_jukebox;
302 
303 		defer_free(argp, kfree, *acl);
304 
305 		(*acl)->naces = nace;
306 		for (ace = (*acl)->aces; ace < (*acl)->aces + nace; ace++) {
307 			READ_BUF(16); len += 16;
308 			READ32(ace->type);
309 			READ32(ace->flag);
310 			READ32(ace->access_mask);
311 			READ32(dummy32);
312 			READ_BUF(dummy32);
313 			len += XDR_QUADLEN(dummy32) << 2;
314 			READMEM(buf, dummy32);
315 			ace->whotype = nfs4_acl_get_whotype(buf, dummy32);
316 			status = nfs_ok;
317 			if (ace->whotype != NFS4_ACL_WHO_NAMED)
318 				;
319 			else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
320 				status = nfsd_map_name_to_gid(argp->rqstp,
321 						buf, dummy32, &ace->who_gid);
322 			else
323 				status = nfsd_map_name_to_uid(argp->rqstp,
324 						buf, dummy32, &ace->who_uid);
325 			if (status)
326 				return status;
327 		}
328 	} else
329 		*acl = NULL;
330 	if (bmval[1] & FATTR4_WORD1_MODE) {
331 		READ_BUF(4);
332 		len += 4;
333 		READ32(iattr->ia_mode);
334 		iattr->ia_mode &= (S_IFMT | S_IALLUGO);
335 		iattr->ia_valid |= ATTR_MODE;
336 	}
337 	if (bmval[1] & FATTR4_WORD1_OWNER) {
338 		READ_BUF(4);
339 		len += 4;
340 		READ32(dummy32);
341 		READ_BUF(dummy32);
342 		len += (XDR_QUADLEN(dummy32) << 2);
343 		READMEM(buf, dummy32);
344 		if ((status = nfsd_map_name_to_uid(argp->rqstp, buf, dummy32, &iattr->ia_uid)))
345 			return status;
346 		iattr->ia_valid |= ATTR_UID;
347 	}
348 	if (bmval[1] & FATTR4_WORD1_OWNER_GROUP) {
349 		READ_BUF(4);
350 		len += 4;
351 		READ32(dummy32);
352 		READ_BUF(dummy32);
353 		len += (XDR_QUADLEN(dummy32) << 2);
354 		READMEM(buf, dummy32);
355 		if ((status = nfsd_map_name_to_gid(argp->rqstp, buf, dummy32, &iattr->ia_gid)))
356 			return status;
357 		iattr->ia_valid |= ATTR_GID;
358 	}
359 	if (bmval[1] & FATTR4_WORD1_TIME_ACCESS_SET) {
360 		READ_BUF(4);
361 		len += 4;
362 		READ32(dummy32);
363 		switch (dummy32) {
364 		case NFS4_SET_TO_CLIENT_TIME:
365 			/* We require the high 32 bits of 'seconds' to be 0, and we ignore
366 			   all 32 bits of 'nseconds'. */
367 			READ_BUF(12);
368 			len += 12;
369 			READ64(iattr->ia_atime.tv_sec);
370 			READ32(iattr->ia_atime.tv_nsec);
371 			if (iattr->ia_atime.tv_nsec >= (u32)1000000000)
372 				return nfserr_inval;
373 			iattr->ia_valid |= (ATTR_ATIME | ATTR_ATIME_SET);
374 			break;
375 		case NFS4_SET_TO_SERVER_TIME:
376 			iattr->ia_valid |= ATTR_ATIME;
377 			break;
378 		default:
379 			goto xdr_error;
380 		}
381 	}
382 	if (bmval[1] & FATTR4_WORD1_TIME_MODIFY_SET) {
383 		READ_BUF(4);
384 		len += 4;
385 		READ32(dummy32);
386 		switch (dummy32) {
387 		case NFS4_SET_TO_CLIENT_TIME:
388 			/* We require the high 32 bits of 'seconds' to be 0, and we ignore
389 			   all 32 bits of 'nseconds'. */
390 			READ_BUF(12);
391 			len += 12;
392 			READ64(iattr->ia_mtime.tv_sec);
393 			READ32(iattr->ia_mtime.tv_nsec);
394 			if (iattr->ia_mtime.tv_nsec >= (u32)1000000000)
395 				return nfserr_inval;
396 			iattr->ia_valid |= (ATTR_MTIME | ATTR_MTIME_SET);
397 			break;
398 		case NFS4_SET_TO_SERVER_TIME:
399 			iattr->ia_valid |= ATTR_MTIME;
400 			break;
401 		default:
402 			goto xdr_error;
403 		}
404 	}
405 
406 	label->len = 0;
407 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
408 	if (bmval[2] & FATTR4_WORD2_SECURITY_LABEL) {
409 		READ_BUF(4);
410 		len += 4;
411 		READ32(dummy32); /* lfs: we don't use it */
412 		READ_BUF(4);
413 		len += 4;
414 		READ32(dummy32); /* pi: we don't use it either */
415 		READ_BUF(4);
416 		len += 4;
417 		READ32(dummy32);
418 		READ_BUF(dummy32);
419 		if (dummy32 > NFSD4_MAX_SEC_LABEL_LEN)
420 			return nfserr_badlabel;
421 		len += (XDR_QUADLEN(dummy32) << 2);
422 		READMEM(buf, dummy32);
423 		label->data = kzalloc(dummy32 + 1, GFP_KERNEL);
424 		if (!label->data)
425 			return nfserr_jukebox;
426 		label->len = dummy32;
427 		defer_free(argp, kfree, label->data);
428 		memcpy(label->data, buf, dummy32);
429 	}
430 #endif
431 
432 	if (bmval[0] & ~NFSD_WRITEABLE_ATTRS_WORD0
433 	    || bmval[1] & ~NFSD_WRITEABLE_ATTRS_WORD1
434 	    || bmval[2] & ~NFSD_WRITEABLE_ATTRS_WORD2)
435 		READ_BUF(expected_len - len);
436 	else if (len != expected_len)
437 		goto xdr_error;
438 
439 	DECODE_TAIL;
440 }
441 
442 static __be32
443 nfsd4_decode_stateid(struct nfsd4_compoundargs *argp, stateid_t *sid)
444 {
445 	DECODE_HEAD;
446 
447 	READ_BUF(sizeof(stateid_t));
448 	READ32(sid->si_generation);
449 	COPYMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
450 
451 	DECODE_TAIL;
452 }
453 
454 static __be32
455 nfsd4_decode_access(struct nfsd4_compoundargs *argp, struct nfsd4_access *access)
456 {
457 	DECODE_HEAD;
458 
459 	READ_BUF(4);
460 	READ32(access->ac_req_access);
461 
462 	DECODE_TAIL;
463 }
464 
465 static __be32 nfsd4_decode_cb_sec(struct nfsd4_compoundargs *argp, struct nfsd4_cb_sec *cbs)
466 {
467 	DECODE_HEAD;
468 	u32 dummy, uid, gid;
469 	char *machine_name;
470 	int i;
471 	int nr_secflavs;
472 
473 	/* callback_sec_params4 */
474 	READ_BUF(4);
475 	READ32(nr_secflavs);
476 	if (nr_secflavs)
477 		cbs->flavor = (u32)(-1);
478 	else
479 		/* Is this legal? Be generous, take it to mean AUTH_NONE: */
480 		cbs->flavor = 0;
481 	for (i = 0; i < nr_secflavs; ++i) {
482 		READ_BUF(4);
483 		READ32(dummy);
484 		switch (dummy) {
485 		case RPC_AUTH_NULL:
486 			/* Nothing to read */
487 			if (cbs->flavor == (u32)(-1))
488 				cbs->flavor = RPC_AUTH_NULL;
489 			break;
490 		case RPC_AUTH_UNIX:
491 			READ_BUF(8);
492 			/* stamp */
493 			READ32(dummy);
494 
495 			/* machine name */
496 			READ32(dummy);
497 			READ_BUF(dummy);
498 			SAVEMEM(machine_name, dummy);
499 
500 			/* uid, gid */
501 			READ_BUF(8);
502 			READ32(uid);
503 			READ32(gid);
504 
505 			/* more gids */
506 			READ_BUF(4);
507 			READ32(dummy);
508 			READ_BUF(dummy * 4);
509 			if (cbs->flavor == (u32)(-1)) {
510 				kuid_t kuid = make_kuid(&init_user_ns, uid);
511 				kgid_t kgid = make_kgid(&init_user_ns, gid);
512 				if (uid_valid(kuid) && gid_valid(kgid)) {
513 					cbs->uid = kuid;
514 					cbs->gid = kgid;
515 					cbs->flavor = RPC_AUTH_UNIX;
516 				} else {
517 					dprintk("RPC_AUTH_UNIX with invalid"
518 						"uid or gid ignoring!\n");
519 				}
520 			}
521 			break;
522 		case RPC_AUTH_GSS:
523 			dprintk("RPC_AUTH_GSS callback secflavor "
524 				"not supported!\n");
525 			READ_BUF(8);
526 			/* gcbp_service */
527 			READ32(dummy);
528 			/* gcbp_handle_from_server */
529 			READ32(dummy);
530 			READ_BUF(dummy);
531 			p += XDR_QUADLEN(dummy);
532 			/* gcbp_handle_from_client */
533 			READ_BUF(4);
534 			READ32(dummy);
535 			READ_BUF(dummy);
536 			break;
537 		default:
538 			dprintk("Illegal callback secflavor\n");
539 			return nfserr_inval;
540 		}
541 	}
542 	DECODE_TAIL;
543 }
544 
545 static __be32 nfsd4_decode_backchannel_ctl(struct nfsd4_compoundargs *argp, struct nfsd4_backchannel_ctl *bc)
546 {
547 	DECODE_HEAD;
548 
549 	READ_BUF(4);
550 	READ32(bc->bc_cb_program);
551 	nfsd4_decode_cb_sec(argp, &bc->bc_cb_sec);
552 
553 	DECODE_TAIL;
554 }
555 
556 static __be32 nfsd4_decode_bind_conn_to_session(struct nfsd4_compoundargs *argp, struct nfsd4_bind_conn_to_session *bcts)
557 {
558 	DECODE_HEAD;
559 
560 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 8);
561 	COPYMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
562 	READ32(bcts->dir);
563 	/* XXX: skipping ctsa_use_conn_in_rdma_mode.  Perhaps Tom Tucker
564 	 * could help us figure out we should be using it. */
565 	DECODE_TAIL;
566 }
567 
568 static __be32
569 nfsd4_decode_close(struct nfsd4_compoundargs *argp, struct nfsd4_close *close)
570 {
571 	DECODE_HEAD;
572 
573 	READ_BUF(4);
574 	READ32(close->cl_seqid);
575 	return nfsd4_decode_stateid(argp, &close->cl_stateid);
576 
577 	DECODE_TAIL;
578 }
579 
580 
581 static __be32
582 nfsd4_decode_commit(struct nfsd4_compoundargs *argp, struct nfsd4_commit *commit)
583 {
584 	DECODE_HEAD;
585 
586 	READ_BUF(12);
587 	READ64(commit->co_offset);
588 	READ32(commit->co_count);
589 
590 	DECODE_TAIL;
591 }
592 
593 static __be32
594 nfsd4_decode_create(struct nfsd4_compoundargs *argp, struct nfsd4_create *create)
595 {
596 	DECODE_HEAD;
597 
598 	READ_BUF(4);
599 	READ32(create->cr_type);
600 	switch (create->cr_type) {
601 	case NF4LNK:
602 		READ_BUF(4);
603 		READ32(create->cr_linklen);
604 		READ_BUF(create->cr_linklen);
605 		SAVEMEM(create->cr_linkname, create->cr_linklen);
606 		break;
607 	case NF4BLK:
608 	case NF4CHR:
609 		READ_BUF(8);
610 		READ32(create->cr_specdata1);
611 		READ32(create->cr_specdata2);
612 		break;
613 	case NF4SOCK:
614 	case NF4FIFO:
615 	case NF4DIR:
616 	default:
617 		break;
618 	}
619 
620 	READ_BUF(4);
621 	READ32(create->cr_namelen);
622 	READ_BUF(create->cr_namelen);
623 	SAVEMEM(create->cr_name, create->cr_namelen);
624 	if ((status = check_filename(create->cr_name, create->cr_namelen)))
625 		return status;
626 
627 	status = nfsd4_decode_fattr(argp, create->cr_bmval, &create->cr_iattr,
628 				    &create->cr_acl, &create->cr_label);
629 	if (status)
630 		goto out;
631 
632 	DECODE_TAIL;
633 }
634 
635 static inline __be32
636 nfsd4_decode_delegreturn(struct nfsd4_compoundargs *argp, struct nfsd4_delegreturn *dr)
637 {
638 	return nfsd4_decode_stateid(argp, &dr->dr_stateid);
639 }
640 
641 static inline __be32
642 nfsd4_decode_getattr(struct nfsd4_compoundargs *argp, struct nfsd4_getattr *getattr)
643 {
644 	return nfsd4_decode_bitmap(argp, getattr->ga_bmval);
645 }
646 
647 static __be32
648 nfsd4_decode_link(struct nfsd4_compoundargs *argp, struct nfsd4_link *link)
649 {
650 	DECODE_HEAD;
651 
652 	READ_BUF(4);
653 	READ32(link->li_namelen);
654 	READ_BUF(link->li_namelen);
655 	SAVEMEM(link->li_name, link->li_namelen);
656 	if ((status = check_filename(link->li_name, link->li_namelen)))
657 		return status;
658 
659 	DECODE_TAIL;
660 }
661 
662 static __be32
663 nfsd4_decode_lock(struct nfsd4_compoundargs *argp, struct nfsd4_lock *lock)
664 {
665 	DECODE_HEAD;
666 
667 	/*
668 	* type, reclaim(boolean), offset, length, new_lock_owner(boolean)
669 	*/
670 	READ_BUF(28);
671 	READ32(lock->lk_type);
672 	if ((lock->lk_type < NFS4_READ_LT) || (lock->lk_type > NFS4_WRITEW_LT))
673 		goto xdr_error;
674 	READ32(lock->lk_reclaim);
675 	READ64(lock->lk_offset);
676 	READ64(lock->lk_length);
677 	READ32(lock->lk_is_new);
678 
679 	if (lock->lk_is_new) {
680 		READ_BUF(4);
681 		READ32(lock->lk_new_open_seqid);
682 		status = nfsd4_decode_stateid(argp, &lock->lk_new_open_stateid);
683 		if (status)
684 			return status;
685 		READ_BUF(8 + sizeof(clientid_t));
686 		READ32(lock->lk_new_lock_seqid);
687 		COPYMEM(&lock->lk_new_clientid, sizeof(clientid_t));
688 		READ32(lock->lk_new_owner.len);
689 		READ_BUF(lock->lk_new_owner.len);
690 		READMEM(lock->lk_new_owner.data, lock->lk_new_owner.len);
691 	} else {
692 		status = nfsd4_decode_stateid(argp, &lock->lk_old_lock_stateid);
693 		if (status)
694 			return status;
695 		READ_BUF(4);
696 		READ32(lock->lk_old_lock_seqid);
697 	}
698 
699 	DECODE_TAIL;
700 }
701 
702 static __be32
703 nfsd4_decode_lockt(struct nfsd4_compoundargs *argp, struct nfsd4_lockt *lockt)
704 {
705 	DECODE_HEAD;
706 
707 	READ_BUF(32);
708 	READ32(lockt->lt_type);
709 	if((lockt->lt_type < NFS4_READ_LT) || (lockt->lt_type > NFS4_WRITEW_LT))
710 		goto xdr_error;
711 	READ64(lockt->lt_offset);
712 	READ64(lockt->lt_length);
713 	COPYMEM(&lockt->lt_clientid, 8);
714 	READ32(lockt->lt_owner.len);
715 	READ_BUF(lockt->lt_owner.len);
716 	READMEM(lockt->lt_owner.data, lockt->lt_owner.len);
717 
718 	DECODE_TAIL;
719 }
720 
721 static __be32
722 nfsd4_decode_locku(struct nfsd4_compoundargs *argp, struct nfsd4_locku *locku)
723 {
724 	DECODE_HEAD;
725 
726 	READ_BUF(8);
727 	READ32(locku->lu_type);
728 	if ((locku->lu_type < NFS4_READ_LT) || (locku->lu_type > NFS4_WRITEW_LT))
729 		goto xdr_error;
730 	READ32(locku->lu_seqid);
731 	status = nfsd4_decode_stateid(argp, &locku->lu_stateid);
732 	if (status)
733 		return status;
734 	READ_BUF(16);
735 	READ64(locku->lu_offset);
736 	READ64(locku->lu_length);
737 
738 	DECODE_TAIL;
739 }
740 
741 static __be32
742 nfsd4_decode_lookup(struct nfsd4_compoundargs *argp, struct nfsd4_lookup *lookup)
743 {
744 	DECODE_HEAD;
745 
746 	READ_BUF(4);
747 	READ32(lookup->lo_len);
748 	READ_BUF(lookup->lo_len);
749 	SAVEMEM(lookup->lo_name, lookup->lo_len);
750 	if ((status = check_filename(lookup->lo_name, lookup->lo_len)))
751 		return status;
752 
753 	DECODE_TAIL;
754 }
755 
756 static __be32 nfsd4_decode_share_access(struct nfsd4_compoundargs *argp, u32 *share_access, u32 *deleg_want, u32 *deleg_when)
757 {
758 	__be32 *p;
759 	u32 w;
760 
761 	READ_BUF(4);
762 	READ32(w);
763 	*share_access = w & NFS4_SHARE_ACCESS_MASK;
764 	*deleg_want = w & NFS4_SHARE_WANT_MASK;
765 	if (deleg_when)
766 		*deleg_when = w & NFS4_SHARE_WHEN_MASK;
767 
768 	switch (w & NFS4_SHARE_ACCESS_MASK) {
769 	case NFS4_SHARE_ACCESS_READ:
770 	case NFS4_SHARE_ACCESS_WRITE:
771 	case NFS4_SHARE_ACCESS_BOTH:
772 		break;
773 	default:
774 		return nfserr_bad_xdr;
775 	}
776 	w &= ~NFS4_SHARE_ACCESS_MASK;
777 	if (!w)
778 		return nfs_ok;
779 	if (!argp->minorversion)
780 		return nfserr_bad_xdr;
781 	switch (w & NFS4_SHARE_WANT_MASK) {
782 	case NFS4_SHARE_WANT_NO_PREFERENCE:
783 	case NFS4_SHARE_WANT_READ_DELEG:
784 	case NFS4_SHARE_WANT_WRITE_DELEG:
785 	case NFS4_SHARE_WANT_ANY_DELEG:
786 	case NFS4_SHARE_WANT_NO_DELEG:
787 	case NFS4_SHARE_WANT_CANCEL:
788 		break;
789 	default:
790 		return nfserr_bad_xdr;
791 	}
792 	w &= ~NFS4_SHARE_WANT_MASK;
793 	if (!w)
794 		return nfs_ok;
795 
796 	if (!deleg_when)	/* open_downgrade */
797 		return nfserr_inval;
798 	switch (w) {
799 	case NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL:
800 	case NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED:
801 	case (NFS4_SHARE_SIGNAL_DELEG_WHEN_RESRC_AVAIL |
802 	      NFS4_SHARE_PUSH_DELEG_WHEN_UNCONTENDED):
803 		return nfs_ok;
804 	}
805 xdr_error:
806 	return nfserr_bad_xdr;
807 }
808 
809 static __be32 nfsd4_decode_share_deny(struct nfsd4_compoundargs *argp, u32 *x)
810 {
811 	__be32 *p;
812 
813 	READ_BUF(4);
814 	READ32(*x);
815 	/* Note: unlinke access bits, deny bits may be zero. */
816 	if (*x & ~NFS4_SHARE_DENY_BOTH)
817 		return nfserr_bad_xdr;
818 	return nfs_ok;
819 xdr_error:
820 	return nfserr_bad_xdr;
821 }
822 
823 static __be32 nfsd4_decode_opaque(struct nfsd4_compoundargs *argp, struct xdr_netobj *o)
824 {
825 	__be32 *p;
826 
827 	READ_BUF(4);
828 	READ32(o->len);
829 
830 	if (o->len == 0 || o->len > NFS4_OPAQUE_LIMIT)
831 		return nfserr_bad_xdr;
832 
833 	READ_BUF(o->len);
834 	SAVEMEM(o->data, o->len);
835 	return nfs_ok;
836 xdr_error:
837 	return nfserr_bad_xdr;
838 }
839 
840 static __be32
841 nfsd4_decode_open(struct nfsd4_compoundargs *argp, struct nfsd4_open *open)
842 {
843 	DECODE_HEAD;
844 	u32 dummy;
845 
846 	memset(open->op_bmval, 0, sizeof(open->op_bmval));
847 	open->op_iattr.ia_valid = 0;
848 	open->op_openowner = NULL;
849 
850 	open->op_xdr_error = 0;
851 	/* seqid, share_access, share_deny, clientid, ownerlen */
852 	READ_BUF(4);
853 	READ32(open->op_seqid);
854 	/* decode, yet ignore deleg_when until supported */
855 	status = nfsd4_decode_share_access(argp, &open->op_share_access,
856 					   &open->op_deleg_want, &dummy);
857 	if (status)
858 		goto xdr_error;
859 	status = nfsd4_decode_share_deny(argp, &open->op_share_deny);
860 	if (status)
861 		goto xdr_error;
862 	READ_BUF(sizeof(clientid_t));
863 	COPYMEM(&open->op_clientid, sizeof(clientid_t));
864 	status = nfsd4_decode_opaque(argp, &open->op_owner);
865 	if (status)
866 		goto xdr_error;
867 	READ_BUF(4);
868 	READ32(open->op_create);
869 	switch (open->op_create) {
870 	case NFS4_OPEN_NOCREATE:
871 		break;
872 	case NFS4_OPEN_CREATE:
873 		READ_BUF(4);
874 		READ32(open->op_createmode);
875 		switch (open->op_createmode) {
876 		case NFS4_CREATE_UNCHECKED:
877 		case NFS4_CREATE_GUARDED:
878 			status = nfsd4_decode_fattr(argp, open->op_bmval,
879 				&open->op_iattr, &open->op_acl, &open->op_label);
880 			if (status)
881 				goto out;
882 			break;
883 		case NFS4_CREATE_EXCLUSIVE:
884 			READ_BUF(NFS4_VERIFIER_SIZE);
885 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
886 			break;
887 		case NFS4_CREATE_EXCLUSIVE4_1:
888 			if (argp->minorversion < 1)
889 				goto xdr_error;
890 			READ_BUF(NFS4_VERIFIER_SIZE);
891 			COPYMEM(open->op_verf.data, NFS4_VERIFIER_SIZE);
892 			status = nfsd4_decode_fattr(argp, open->op_bmval,
893 				&open->op_iattr, &open->op_acl, &open->op_label);
894 			if (status)
895 				goto out;
896 			break;
897 		default:
898 			goto xdr_error;
899 		}
900 		break;
901 	default:
902 		goto xdr_error;
903 	}
904 
905 	/* open_claim */
906 	READ_BUF(4);
907 	READ32(open->op_claim_type);
908 	switch (open->op_claim_type) {
909 	case NFS4_OPEN_CLAIM_NULL:
910 	case NFS4_OPEN_CLAIM_DELEGATE_PREV:
911 		READ_BUF(4);
912 		READ32(open->op_fname.len);
913 		READ_BUF(open->op_fname.len);
914 		SAVEMEM(open->op_fname.data, open->op_fname.len);
915 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
916 			return status;
917 		break;
918 	case NFS4_OPEN_CLAIM_PREVIOUS:
919 		READ_BUF(4);
920 		READ32(open->op_delegate_type);
921 		break;
922 	case NFS4_OPEN_CLAIM_DELEGATE_CUR:
923 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
924 		if (status)
925 			return status;
926 		READ_BUF(4);
927 		READ32(open->op_fname.len);
928 		READ_BUF(open->op_fname.len);
929 		SAVEMEM(open->op_fname.data, open->op_fname.len);
930 		if ((status = check_filename(open->op_fname.data, open->op_fname.len)))
931 			return status;
932 		break;
933 	case NFS4_OPEN_CLAIM_FH:
934 	case NFS4_OPEN_CLAIM_DELEG_PREV_FH:
935 		if (argp->minorversion < 1)
936 			goto xdr_error;
937 		/* void */
938 		break;
939 	case NFS4_OPEN_CLAIM_DELEG_CUR_FH:
940 		if (argp->minorversion < 1)
941 			goto xdr_error;
942 		status = nfsd4_decode_stateid(argp, &open->op_delegate_stateid);
943 		if (status)
944 			return status;
945 		break;
946 	default:
947 		goto xdr_error;
948 	}
949 
950 	DECODE_TAIL;
951 }
952 
953 static __be32
954 nfsd4_decode_open_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_open_confirm *open_conf)
955 {
956 	DECODE_HEAD;
957 
958 	if (argp->minorversion >= 1)
959 		return nfserr_notsupp;
960 
961 	status = nfsd4_decode_stateid(argp, &open_conf->oc_req_stateid);
962 	if (status)
963 		return status;
964 	READ_BUF(4);
965 	READ32(open_conf->oc_seqid);
966 
967 	DECODE_TAIL;
968 }
969 
970 static __be32
971 nfsd4_decode_open_downgrade(struct nfsd4_compoundargs *argp, struct nfsd4_open_downgrade *open_down)
972 {
973 	DECODE_HEAD;
974 
975 	status = nfsd4_decode_stateid(argp, &open_down->od_stateid);
976 	if (status)
977 		return status;
978 	READ_BUF(4);
979 	READ32(open_down->od_seqid);
980 	status = nfsd4_decode_share_access(argp, &open_down->od_share_access,
981 					   &open_down->od_deleg_want, NULL);
982 	if (status)
983 		return status;
984 	status = nfsd4_decode_share_deny(argp, &open_down->od_share_deny);
985 	if (status)
986 		return status;
987 	DECODE_TAIL;
988 }
989 
990 static __be32
991 nfsd4_decode_putfh(struct nfsd4_compoundargs *argp, struct nfsd4_putfh *putfh)
992 {
993 	DECODE_HEAD;
994 
995 	READ_BUF(4);
996 	READ32(putfh->pf_fhlen);
997 	if (putfh->pf_fhlen > NFS4_FHSIZE)
998 		goto xdr_error;
999 	READ_BUF(putfh->pf_fhlen);
1000 	SAVEMEM(putfh->pf_fhval, putfh->pf_fhlen);
1001 
1002 	DECODE_TAIL;
1003 }
1004 
1005 static __be32
1006 nfsd4_decode_putpubfh(struct nfsd4_compoundargs *argp, void *p)
1007 {
1008 	if (argp->minorversion == 0)
1009 		return nfs_ok;
1010 	return nfserr_notsupp;
1011 }
1012 
1013 static __be32
1014 nfsd4_decode_read(struct nfsd4_compoundargs *argp, struct nfsd4_read *read)
1015 {
1016 	DECODE_HEAD;
1017 
1018 	status = nfsd4_decode_stateid(argp, &read->rd_stateid);
1019 	if (status)
1020 		return status;
1021 	READ_BUF(12);
1022 	READ64(read->rd_offset);
1023 	READ32(read->rd_length);
1024 
1025 	DECODE_TAIL;
1026 }
1027 
1028 static __be32
1029 nfsd4_decode_readdir(struct nfsd4_compoundargs *argp, struct nfsd4_readdir *readdir)
1030 {
1031 	DECODE_HEAD;
1032 
1033 	READ_BUF(24);
1034 	READ64(readdir->rd_cookie);
1035 	COPYMEM(readdir->rd_verf.data, sizeof(readdir->rd_verf.data));
1036 	READ32(readdir->rd_dircount);    /* just in case you needed a useless field... */
1037 	READ32(readdir->rd_maxcount);
1038 	if ((status = nfsd4_decode_bitmap(argp, readdir->rd_bmval)))
1039 		goto out;
1040 
1041 	DECODE_TAIL;
1042 }
1043 
1044 static __be32
1045 nfsd4_decode_remove(struct nfsd4_compoundargs *argp, struct nfsd4_remove *remove)
1046 {
1047 	DECODE_HEAD;
1048 
1049 	READ_BUF(4);
1050 	READ32(remove->rm_namelen);
1051 	READ_BUF(remove->rm_namelen);
1052 	SAVEMEM(remove->rm_name, remove->rm_namelen);
1053 	if ((status = check_filename(remove->rm_name, remove->rm_namelen)))
1054 		return status;
1055 
1056 	DECODE_TAIL;
1057 }
1058 
1059 static __be32
1060 nfsd4_decode_rename(struct nfsd4_compoundargs *argp, struct nfsd4_rename *rename)
1061 {
1062 	DECODE_HEAD;
1063 
1064 	READ_BUF(4);
1065 	READ32(rename->rn_snamelen);
1066 	READ_BUF(rename->rn_snamelen + 4);
1067 	SAVEMEM(rename->rn_sname, rename->rn_snamelen);
1068 	READ32(rename->rn_tnamelen);
1069 	READ_BUF(rename->rn_tnamelen);
1070 	SAVEMEM(rename->rn_tname, rename->rn_tnamelen);
1071 	if ((status = check_filename(rename->rn_sname, rename->rn_snamelen)))
1072 		return status;
1073 	if ((status = check_filename(rename->rn_tname, rename->rn_tnamelen)))
1074 		return status;
1075 
1076 	DECODE_TAIL;
1077 }
1078 
1079 static __be32
1080 nfsd4_decode_renew(struct nfsd4_compoundargs *argp, clientid_t *clientid)
1081 {
1082 	DECODE_HEAD;
1083 
1084 	if (argp->minorversion >= 1)
1085 		return nfserr_notsupp;
1086 
1087 	READ_BUF(sizeof(clientid_t));
1088 	COPYMEM(clientid, sizeof(clientid_t));
1089 
1090 	DECODE_TAIL;
1091 }
1092 
1093 static __be32
1094 nfsd4_decode_secinfo(struct nfsd4_compoundargs *argp,
1095 		     struct nfsd4_secinfo *secinfo)
1096 {
1097 	DECODE_HEAD;
1098 
1099 	READ_BUF(4);
1100 	READ32(secinfo->si_namelen);
1101 	READ_BUF(secinfo->si_namelen);
1102 	SAVEMEM(secinfo->si_name, secinfo->si_namelen);
1103 	status = check_filename(secinfo->si_name, secinfo->si_namelen);
1104 	if (status)
1105 		return status;
1106 	DECODE_TAIL;
1107 }
1108 
1109 static __be32
1110 nfsd4_decode_secinfo_no_name(struct nfsd4_compoundargs *argp,
1111 		     struct nfsd4_secinfo_no_name *sin)
1112 {
1113 	DECODE_HEAD;
1114 
1115 	READ_BUF(4);
1116 	READ32(sin->sin_style);
1117 	DECODE_TAIL;
1118 }
1119 
1120 static __be32
1121 nfsd4_decode_setattr(struct nfsd4_compoundargs *argp, struct nfsd4_setattr *setattr)
1122 {
1123 	__be32 status;
1124 
1125 	status = nfsd4_decode_stateid(argp, &setattr->sa_stateid);
1126 	if (status)
1127 		return status;
1128 	return nfsd4_decode_fattr(argp, setattr->sa_bmval, &setattr->sa_iattr,
1129 				  &setattr->sa_acl, &setattr->sa_label);
1130 }
1131 
1132 static __be32
1133 nfsd4_decode_setclientid(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid *setclientid)
1134 {
1135 	DECODE_HEAD;
1136 
1137 	if (argp->minorversion >= 1)
1138 		return nfserr_notsupp;
1139 
1140 	READ_BUF(NFS4_VERIFIER_SIZE);
1141 	COPYMEM(setclientid->se_verf.data, NFS4_VERIFIER_SIZE);
1142 
1143 	status = nfsd4_decode_opaque(argp, &setclientid->se_name);
1144 	if (status)
1145 		return nfserr_bad_xdr;
1146 	READ_BUF(8);
1147 	READ32(setclientid->se_callback_prog);
1148 	READ32(setclientid->se_callback_netid_len);
1149 
1150 	READ_BUF(setclientid->se_callback_netid_len + 4);
1151 	SAVEMEM(setclientid->se_callback_netid_val, setclientid->se_callback_netid_len);
1152 	READ32(setclientid->se_callback_addr_len);
1153 
1154 	READ_BUF(setclientid->se_callback_addr_len + 4);
1155 	SAVEMEM(setclientid->se_callback_addr_val, setclientid->se_callback_addr_len);
1156 	READ32(setclientid->se_callback_ident);
1157 
1158 	DECODE_TAIL;
1159 }
1160 
1161 static __be32
1162 nfsd4_decode_setclientid_confirm(struct nfsd4_compoundargs *argp, struct nfsd4_setclientid_confirm *scd_c)
1163 {
1164 	DECODE_HEAD;
1165 
1166 	if (argp->minorversion >= 1)
1167 		return nfserr_notsupp;
1168 
1169 	READ_BUF(8 + NFS4_VERIFIER_SIZE);
1170 	COPYMEM(&scd_c->sc_clientid, 8);
1171 	COPYMEM(&scd_c->sc_confirm, NFS4_VERIFIER_SIZE);
1172 
1173 	DECODE_TAIL;
1174 }
1175 
1176 /* Also used for NVERIFY */
1177 static __be32
1178 nfsd4_decode_verify(struct nfsd4_compoundargs *argp, struct nfsd4_verify *verify)
1179 {
1180 	DECODE_HEAD;
1181 
1182 	if ((status = nfsd4_decode_bitmap(argp, verify->ve_bmval)))
1183 		goto out;
1184 
1185 	/* For convenience's sake, we compare raw xdr'd attributes in
1186 	 * nfsd4_proc_verify */
1187 
1188 	READ_BUF(4);
1189 	READ32(verify->ve_attrlen);
1190 	READ_BUF(verify->ve_attrlen);
1191 	SAVEMEM(verify->ve_attrval, verify->ve_attrlen);
1192 
1193 	DECODE_TAIL;
1194 }
1195 
1196 static __be32
1197 nfsd4_decode_write(struct nfsd4_compoundargs *argp, struct nfsd4_write *write)
1198 {
1199 	int avail;
1200 	int len;
1201 	DECODE_HEAD;
1202 
1203 	status = nfsd4_decode_stateid(argp, &write->wr_stateid);
1204 	if (status)
1205 		return status;
1206 	READ_BUF(16);
1207 	READ64(write->wr_offset);
1208 	READ32(write->wr_stable_how);
1209 	if (write->wr_stable_how > 2)
1210 		goto xdr_error;
1211 	READ32(write->wr_buflen);
1212 
1213 	/* Sorry .. no magic macros for this.. *
1214 	 * READ_BUF(write->wr_buflen);
1215 	 * SAVEMEM(write->wr_buf, write->wr_buflen);
1216 	 */
1217 	avail = (char*)argp->end - (char*)argp->p;
1218 	if (avail + argp->pagelen < write->wr_buflen) {
1219 		dprintk("NFSD: xdr error (%s:%d)\n",
1220 				__FILE__, __LINE__);
1221 		goto xdr_error;
1222 	}
1223 	write->wr_head.iov_base = p;
1224 	write->wr_head.iov_len = avail;
1225 	WARN_ON(avail != (XDR_QUADLEN(avail) << 2));
1226 	write->wr_pagelist = argp->pagelist;
1227 
1228 	len = XDR_QUADLEN(write->wr_buflen) << 2;
1229 	if (len >= avail) {
1230 		int pages;
1231 
1232 		len -= avail;
1233 
1234 		pages = len >> PAGE_SHIFT;
1235 		argp->pagelist += pages;
1236 		argp->pagelen -= pages * PAGE_SIZE;
1237 		len -= pages * PAGE_SIZE;
1238 
1239 		argp->p = (__be32 *)page_address(argp->pagelist[0]);
1240 		argp->pagelist++;
1241 		argp->end = argp->p + XDR_QUADLEN(PAGE_SIZE);
1242 	}
1243 	argp->p += XDR_QUADLEN(len);
1244 
1245 	DECODE_TAIL;
1246 }
1247 
1248 static __be32
1249 nfsd4_decode_release_lockowner(struct nfsd4_compoundargs *argp, struct nfsd4_release_lockowner *rlockowner)
1250 {
1251 	DECODE_HEAD;
1252 
1253 	if (argp->minorversion >= 1)
1254 		return nfserr_notsupp;
1255 
1256 	READ_BUF(12);
1257 	COPYMEM(&rlockowner->rl_clientid, sizeof(clientid_t));
1258 	READ32(rlockowner->rl_owner.len);
1259 	READ_BUF(rlockowner->rl_owner.len);
1260 	READMEM(rlockowner->rl_owner.data, rlockowner->rl_owner.len);
1261 
1262 	if (argp->minorversion && !zero_clientid(&rlockowner->rl_clientid))
1263 		return nfserr_inval;
1264 	DECODE_TAIL;
1265 }
1266 
1267 static __be32
1268 nfsd4_decode_exchange_id(struct nfsd4_compoundargs *argp,
1269 			 struct nfsd4_exchange_id *exid)
1270 {
1271 	int dummy, tmp;
1272 	DECODE_HEAD;
1273 
1274 	READ_BUF(NFS4_VERIFIER_SIZE);
1275 	COPYMEM(exid->verifier.data, NFS4_VERIFIER_SIZE);
1276 
1277 	status = nfsd4_decode_opaque(argp, &exid->clname);
1278 	if (status)
1279 		return nfserr_bad_xdr;
1280 
1281 	READ_BUF(4);
1282 	READ32(exid->flags);
1283 
1284 	/* Ignore state_protect4_a */
1285 	READ_BUF(4);
1286 	READ32(exid->spa_how);
1287 	switch (exid->spa_how) {
1288 	case SP4_NONE:
1289 		break;
1290 	case SP4_MACH_CRED:
1291 		/* spo_must_enforce */
1292 		READ_BUF(4);
1293 		READ32(dummy);
1294 		READ_BUF(dummy * 4);
1295 		p += dummy;
1296 
1297 		/* spo_must_allow */
1298 		READ_BUF(4);
1299 		READ32(dummy);
1300 		READ_BUF(dummy * 4);
1301 		p += dummy;
1302 		break;
1303 	case SP4_SSV:
1304 		/* ssp_ops */
1305 		READ_BUF(4);
1306 		READ32(dummy);
1307 		READ_BUF(dummy * 4);
1308 		p += dummy;
1309 
1310 		READ_BUF(4);
1311 		READ32(dummy);
1312 		READ_BUF(dummy * 4);
1313 		p += dummy;
1314 
1315 		/* ssp_hash_algs<> */
1316 		READ_BUF(4);
1317 		READ32(tmp);
1318 		while (tmp--) {
1319 			READ_BUF(4);
1320 			READ32(dummy);
1321 			READ_BUF(dummy);
1322 			p += XDR_QUADLEN(dummy);
1323 		}
1324 
1325 		/* ssp_encr_algs<> */
1326 		READ_BUF(4);
1327 		READ32(tmp);
1328 		while (tmp--) {
1329 			READ_BUF(4);
1330 			READ32(dummy);
1331 			READ_BUF(dummy);
1332 			p += XDR_QUADLEN(dummy);
1333 		}
1334 
1335 		/* ssp_window and ssp_num_gss_handles */
1336 		READ_BUF(8);
1337 		READ32(dummy);
1338 		READ32(dummy);
1339 		break;
1340 	default:
1341 		goto xdr_error;
1342 	}
1343 
1344 	/* Ignore Implementation ID */
1345 	READ_BUF(4);    /* nfs_impl_id4 array length */
1346 	READ32(dummy);
1347 
1348 	if (dummy > 1)
1349 		goto xdr_error;
1350 
1351 	if (dummy == 1) {
1352 		/* nii_domain */
1353 		READ_BUF(4);
1354 		READ32(dummy);
1355 		READ_BUF(dummy);
1356 		p += XDR_QUADLEN(dummy);
1357 
1358 		/* nii_name */
1359 		READ_BUF(4);
1360 		READ32(dummy);
1361 		READ_BUF(dummy);
1362 		p += XDR_QUADLEN(dummy);
1363 
1364 		/* nii_date */
1365 		READ_BUF(12);
1366 		p += 3;
1367 	}
1368 	DECODE_TAIL;
1369 }
1370 
1371 static __be32
1372 nfsd4_decode_create_session(struct nfsd4_compoundargs *argp,
1373 			    struct nfsd4_create_session *sess)
1374 {
1375 	DECODE_HEAD;
1376 	u32 dummy;
1377 
1378 	READ_BUF(16);
1379 	COPYMEM(&sess->clientid, 8);
1380 	READ32(sess->seqid);
1381 	READ32(sess->flags);
1382 
1383 	/* Fore channel attrs */
1384 	READ_BUF(28);
1385 	READ32(dummy); /* headerpadsz is always 0 */
1386 	READ32(sess->fore_channel.maxreq_sz);
1387 	READ32(sess->fore_channel.maxresp_sz);
1388 	READ32(sess->fore_channel.maxresp_cached);
1389 	READ32(sess->fore_channel.maxops);
1390 	READ32(sess->fore_channel.maxreqs);
1391 	READ32(sess->fore_channel.nr_rdma_attrs);
1392 	if (sess->fore_channel.nr_rdma_attrs == 1) {
1393 		READ_BUF(4);
1394 		READ32(sess->fore_channel.rdma_attrs);
1395 	} else if (sess->fore_channel.nr_rdma_attrs > 1) {
1396 		dprintk("Too many fore channel attr bitmaps!\n");
1397 		goto xdr_error;
1398 	}
1399 
1400 	/* Back channel attrs */
1401 	READ_BUF(28);
1402 	READ32(dummy); /* headerpadsz is always 0 */
1403 	READ32(sess->back_channel.maxreq_sz);
1404 	READ32(sess->back_channel.maxresp_sz);
1405 	READ32(sess->back_channel.maxresp_cached);
1406 	READ32(sess->back_channel.maxops);
1407 	READ32(sess->back_channel.maxreqs);
1408 	READ32(sess->back_channel.nr_rdma_attrs);
1409 	if (sess->back_channel.nr_rdma_attrs == 1) {
1410 		READ_BUF(4);
1411 		READ32(sess->back_channel.rdma_attrs);
1412 	} else if (sess->back_channel.nr_rdma_attrs > 1) {
1413 		dprintk("Too many back channel attr bitmaps!\n");
1414 		goto xdr_error;
1415 	}
1416 
1417 	READ_BUF(4);
1418 	READ32(sess->callback_prog);
1419 	nfsd4_decode_cb_sec(argp, &sess->cb_sec);
1420 	DECODE_TAIL;
1421 }
1422 
1423 static __be32
1424 nfsd4_decode_destroy_session(struct nfsd4_compoundargs *argp,
1425 			     struct nfsd4_destroy_session *destroy_session)
1426 {
1427 	DECODE_HEAD;
1428 	READ_BUF(NFS4_MAX_SESSIONID_LEN);
1429 	COPYMEM(destroy_session->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1430 
1431 	DECODE_TAIL;
1432 }
1433 
1434 static __be32
1435 nfsd4_decode_free_stateid(struct nfsd4_compoundargs *argp,
1436 			  struct nfsd4_free_stateid *free_stateid)
1437 {
1438 	DECODE_HEAD;
1439 
1440 	READ_BUF(sizeof(stateid_t));
1441 	READ32(free_stateid->fr_stateid.si_generation);
1442 	COPYMEM(&free_stateid->fr_stateid.si_opaque, sizeof(stateid_opaque_t));
1443 
1444 	DECODE_TAIL;
1445 }
1446 
1447 static __be32
1448 nfsd4_decode_sequence(struct nfsd4_compoundargs *argp,
1449 		      struct nfsd4_sequence *seq)
1450 {
1451 	DECODE_HEAD;
1452 
1453 	READ_BUF(NFS4_MAX_SESSIONID_LEN + 16);
1454 	COPYMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
1455 	READ32(seq->seqid);
1456 	READ32(seq->slotid);
1457 	READ32(seq->maxslots);
1458 	READ32(seq->cachethis);
1459 
1460 	DECODE_TAIL;
1461 }
1462 
1463 static __be32
1464 nfsd4_decode_test_stateid(struct nfsd4_compoundargs *argp, struct nfsd4_test_stateid *test_stateid)
1465 {
1466 	int i;
1467 	__be32 *p, status;
1468 	struct nfsd4_test_stateid_id *stateid;
1469 
1470 	READ_BUF(4);
1471 	test_stateid->ts_num_ids = ntohl(*p++);
1472 
1473 	INIT_LIST_HEAD(&test_stateid->ts_stateid_list);
1474 
1475 	for (i = 0; i < test_stateid->ts_num_ids; i++) {
1476 		stateid = kmalloc(sizeof(struct nfsd4_test_stateid_id), GFP_KERNEL);
1477 		if (!stateid) {
1478 			status = nfserrno(-ENOMEM);
1479 			goto out;
1480 		}
1481 
1482 		defer_free(argp, kfree, stateid);
1483 		INIT_LIST_HEAD(&stateid->ts_id_list);
1484 		list_add_tail(&stateid->ts_id_list, &test_stateid->ts_stateid_list);
1485 
1486 		status = nfsd4_decode_stateid(argp, &stateid->ts_id_stateid);
1487 		if (status)
1488 			goto out;
1489 	}
1490 
1491 	status = 0;
1492 out:
1493 	return status;
1494 xdr_error:
1495 	dprintk("NFSD: xdr error (%s:%d)\n", __FILE__, __LINE__);
1496 	status = nfserr_bad_xdr;
1497 	goto out;
1498 }
1499 
1500 static __be32 nfsd4_decode_destroy_clientid(struct nfsd4_compoundargs *argp, struct nfsd4_destroy_clientid *dc)
1501 {
1502 	DECODE_HEAD;
1503 
1504 	READ_BUF(8);
1505 	COPYMEM(&dc->clientid, 8);
1506 
1507 	DECODE_TAIL;
1508 }
1509 
1510 static __be32 nfsd4_decode_reclaim_complete(struct nfsd4_compoundargs *argp, struct nfsd4_reclaim_complete *rc)
1511 {
1512 	DECODE_HEAD;
1513 
1514 	READ_BUF(4);
1515 	READ32(rc->rca_one_fs);
1516 
1517 	DECODE_TAIL;
1518 }
1519 
1520 static __be32
1521 nfsd4_decode_noop(struct nfsd4_compoundargs *argp, void *p)
1522 {
1523 	return nfs_ok;
1524 }
1525 
1526 static __be32
1527 nfsd4_decode_notsupp(struct nfsd4_compoundargs *argp, void *p)
1528 {
1529 	return nfserr_notsupp;
1530 }
1531 
1532 typedef __be32(*nfsd4_dec)(struct nfsd4_compoundargs *argp, void *);
1533 
1534 static nfsd4_dec nfsd4_dec_ops[] = {
1535 	[OP_ACCESS]		= (nfsd4_dec)nfsd4_decode_access,
1536 	[OP_CLOSE]		= (nfsd4_dec)nfsd4_decode_close,
1537 	[OP_COMMIT]		= (nfsd4_dec)nfsd4_decode_commit,
1538 	[OP_CREATE]		= (nfsd4_dec)nfsd4_decode_create,
1539 	[OP_DELEGPURGE]		= (nfsd4_dec)nfsd4_decode_notsupp,
1540 	[OP_DELEGRETURN]	= (nfsd4_dec)nfsd4_decode_delegreturn,
1541 	[OP_GETATTR]		= (nfsd4_dec)nfsd4_decode_getattr,
1542 	[OP_GETFH]		= (nfsd4_dec)nfsd4_decode_noop,
1543 	[OP_LINK]		= (nfsd4_dec)nfsd4_decode_link,
1544 	[OP_LOCK]		= (nfsd4_dec)nfsd4_decode_lock,
1545 	[OP_LOCKT]		= (nfsd4_dec)nfsd4_decode_lockt,
1546 	[OP_LOCKU]		= (nfsd4_dec)nfsd4_decode_locku,
1547 	[OP_LOOKUP]		= (nfsd4_dec)nfsd4_decode_lookup,
1548 	[OP_LOOKUPP]		= (nfsd4_dec)nfsd4_decode_noop,
1549 	[OP_NVERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1550 	[OP_OPEN]		= (nfsd4_dec)nfsd4_decode_open,
1551 	[OP_OPENATTR]		= (nfsd4_dec)nfsd4_decode_notsupp,
1552 	[OP_OPEN_CONFIRM]	= (nfsd4_dec)nfsd4_decode_open_confirm,
1553 	[OP_OPEN_DOWNGRADE]	= (nfsd4_dec)nfsd4_decode_open_downgrade,
1554 	[OP_PUTFH]		= (nfsd4_dec)nfsd4_decode_putfh,
1555 	[OP_PUTPUBFH]		= (nfsd4_dec)nfsd4_decode_putpubfh,
1556 	[OP_PUTROOTFH]		= (nfsd4_dec)nfsd4_decode_noop,
1557 	[OP_READ]		= (nfsd4_dec)nfsd4_decode_read,
1558 	[OP_READDIR]		= (nfsd4_dec)nfsd4_decode_readdir,
1559 	[OP_READLINK]		= (nfsd4_dec)nfsd4_decode_noop,
1560 	[OP_REMOVE]		= (nfsd4_dec)nfsd4_decode_remove,
1561 	[OP_RENAME]		= (nfsd4_dec)nfsd4_decode_rename,
1562 	[OP_RENEW]		= (nfsd4_dec)nfsd4_decode_renew,
1563 	[OP_RESTOREFH]		= (nfsd4_dec)nfsd4_decode_noop,
1564 	[OP_SAVEFH]		= (nfsd4_dec)nfsd4_decode_noop,
1565 	[OP_SECINFO]		= (nfsd4_dec)nfsd4_decode_secinfo,
1566 	[OP_SETATTR]		= (nfsd4_dec)nfsd4_decode_setattr,
1567 	[OP_SETCLIENTID]	= (nfsd4_dec)nfsd4_decode_setclientid,
1568 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_dec)nfsd4_decode_setclientid_confirm,
1569 	[OP_VERIFY]		= (nfsd4_dec)nfsd4_decode_verify,
1570 	[OP_WRITE]		= (nfsd4_dec)nfsd4_decode_write,
1571 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_dec)nfsd4_decode_release_lockowner,
1572 
1573 	/* new operations for NFSv4.1 */
1574 	[OP_BACKCHANNEL_CTL]	= (nfsd4_dec)nfsd4_decode_backchannel_ctl,
1575 	[OP_BIND_CONN_TO_SESSION]= (nfsd4_dec)nfsd4_decode_bind_conn_to_session,
1576 	[OP_EXCHANGE_ID]	= (nfsd4_dec)nfsd4_decode_exchange_id,
1577 	[OP_CREATE_SESSION]	= (nfsd4_dec)nfsd4_decode_create_session,
1578 	[OP_DESTROY_SESSION]	= (nfsd4_dec)nfsd4_decode_destroy_session,
1579 	[OP_FREE_STATEID]	= (nfsd4_dec)nfsd4_decode_free_stateid,
1580 	[OP_GET_DIR_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1581 	[OP_GETDEVICEINFO]	= (nfsd4_dec)nfsd4_decode_notsupp,
1582 	[OP_GETDEVICELIST]	= (nfsd4_dec)nfsd4_decode_notsupp,
1583 	[OP_LAYOUTCOMMIT]	= (nfsd4_dec)nfsd4_decode_notsupp,
1584 	[OP_LAYOUTGET]		= (nfsd4_dec)nfsd4_decode_notsupp,
1585 	[OP_LAYOUTRETURN]	= (nfsd4_dec)nfsd4_decode_notsupp,
1586 	[OP_SECINFO_NO_NAME]	= (nfsd4_dec)nfsd4_decode_secinfo_no_name,
1587 	[OP_SEQUENCE]		= (nfsd4_dec)nfsd4_decode_sequence,
1588 	[OP_SET_SSV]		= (nfsd4_dec)nfsd4_decode_notsupp,
1589 	[OP_TEST_STATEID]	= (nfsd4_dec)nfsd4_decode_test_stateid,
1590 	[OP_WANT_DELEGATION]	= (nfsd4_dec)nfsd4_decode_notsupp,
1591 	[OP_DESTROY_CLIENTID]	= (nfsd4_dec)nfsd4_decode_destroy_clientid,
1592 	[OP_RECLAIM_COMPLETE]	= (nfsd4_dec)nfsd4_decode_reclaim_complete,
1593 };
1594 
1595 static inline bool
1596 nfsd4_opnum_in_range(struct nfsd4_compoundargs *argp, struct nfsd4_op *op)
1597 {
1598 	if (op->opnum < FIRST_NFS4_OP)
1599 		return false;
1600 	else if (argp->minorversion == 0 && op->opnum > LAST_NFS40_OP)
1601 		return false;
1602 	else if (argp->minorversion == 1 && op->opnum > LAST_NFS41_OP)
1603 		return false;
1604 	else if (argp->minorversion == 2 && op->opnum > LAST_NFS42_OP)
1605 		return false;
1606 	return true;
1607 }
1608 
1609 /*
1610  * Return a rough estimate of the maximum possible reply size.  Note the
1611  * estimate includes rpc headers so is meant to be passed to
1612  * svc_reserve, not svc_reserve_auth.
1613  *
1614  * Also note the current compound encoding permits only one operation to
1615  * use pages beyond the first one, so the maximum possible length is the
1616  * maximum over these values, not the sum.
1617  */
1618 static int nfsd4_max_reply(u32 opnum)
1619 {
1620 	switch (opnum) {
1621 	case OP_READLINK:
1622 	case OP_READDIR:
1623 		/*
1624 		 * Both of these ops take a single page for data and put
1625 		 * the head and tail in another page:
1626 		 */
1627 		return 2 * PAGE_SIZE;
1628 	case OP_READ:
1629 		return INT_MAX;
1630 	default:
1631 		return PAGE_SIZE;
1632 	}
1633 }
1634 
1635 static __be32
1636 nfsd4_decode_compound(struct nfsd4_compoundargs *argp)
1637 {
1638 	DECODE_HEAD;
1639 	struct nfsd4_op *op;
1640 	bool cachethis = false;
1641 	int max_reply = PAGE_SIZE;
1642 	int i;
1643 
1644 	READ_BUF(4);
1645 	READ32(argp->taglen);
1646 	READ_BUF(argp->taglen + 8);
1647 	SAVEMEM(argp->tag, argp->taglen);
1648 	READ32(argp->minorversion);
1649 	READ32(argp->opcnt);
1650 
1651 	if (argp->taglen > NFSD4_MAX_TAGLEN)
1652 		goto xdr_error;
1653 	if (argp->opcnt > 100)
1654 		goto xdr_error;
1655 
1656 	if (argp->opcnt > ARRAY_SIZE(argp->iops)) {
1657 		argp->ops = kmalloc(argp->opcnt * sizeof(*argp->ops), GFP_KERNEL);
1658 		if (!argp->ops) {
1659 			argp->ops = argp->iops;
1660 			dprintk("nfsd: couldn't allocate room for COMPOUND\n");
1661 			goto xdr_error;
1662 		}
1663 	}
1664 
1665 	if (argp->minorversion > NFSD_SUPPORTED_MINOR_VERSION)
1666 		argp->opcnt = 0;
1667 
1668 	for (i = 0; i < argp->opcnt; i++) {
1669 		op = &argp->ops[i];
1670 		op->replay = NULL;
1671 
1672 		READ_BUF(4);
1673 		READ32(op->opnum);
1674 
1675 		if (nfsd4_opnum_in_range(argp, op))
1676 			op->status = nfsd4_dec_ops[op->opnum](argp, &op->u);
1677 		else {
1678 			op->opnum = OP_ILLEGAL;
1679 			op->status = nfserr_op_illegal;
1680 		}
1681 
1682 		if (op->status) {
1683 			argp->opcnt = i+1;
1684 			break;
1685 		}
1686 		/*
1687 		 * We'll try to cache the result in the DRC if any one
1688 		 * op in the compound wants to be cached:
1689 		 */
1690 		cachethis |= nfsd4_cache_this_op(op);
1691 
1692 		max_reply = max(max_reply, nfsd4_max_reply(op->opnum));
1693 	}
1694 	/* Sessions make the DRC unnecessary: */
1695 	if (argp->minorversion)
1696 		cachethis = false;
1697 	if (max_reply != INT_MAX)
1698 		svc_reserve(argp->rqstp, max_reply);
1699 	argp->rqstp->rq_cachetype = cachethis ? RC_REPLBUFF : RC_NOCACHE;
1700 
1701 	DECODE_TAIL;
1702 }
1703 
1704 #define WRITE32(n)               *p++ = htonl(n)
1705 #define WRITE64(n)               do {				\
1706 	*p++ = htonl((u32)((n) >> 32));				\
1707 	*p++ = htonl((u32)(n));					\
1708 } while (0)
1709 #define WRITEMEM(ptr,nbytes)     do { if (nbytes > 0) {		\
1710 	*(p + XDR_QUADLEN(nbytes) -1) = 0;                      \
1711 	memcpy(p, ptr, nbytes);					\
1712 	p += XDR_QUADLEN(nbytes);				\
1713 }} while (0)
1714 
1715 static void write32(__be32 **p, u32 n)
1716 {
1717 	*(*p)++ = htonl(n);
1718 }
1719 
1720 static void write64(__be32 **p, u64 n)
1721 {
1722 	write32(p, (n >> 32));
1723 	write32(p, (u32)n);
1724 }
1725 
1726 static void write_change(__be32 **p, struct kstat *stat, struct inode *inode)
1727 {
1728 	if (IS_I_VERSION(inode)) {
1729 		write64(p, inode->i_version);
1730 	} else {
1731 		write32(p, stat->ctime.tv_sec);
1732 		write32(p, stat->ctime.tv_nsec);
1733 	}
1734 }
1735 
1736 static void write_cinfo(__be32 **p, struct nfsd4_change_info *c)
1737 {
1738 	write32(p, c->atomic);
1739 	if (c->change_supported) {
1740 		write64(p, c->before_change);
1741 		write64(p, c->after_change);
1742 	} else {
1743 		write32(p, c->before_ctime_sec);
1744 		write32(p, c->before_ctime_nsec);
1745 		write32(p, c->after_ctime_sec);
1746 		write32(p, c->after_ctime_nsec);
1747 	}
1748 }
1749 
1750 #define RESERVE_SPACE(nbytes)	do {				\
1751 	p = resp->p;						\
1752 	BUG_ON(p + XDR_QUADLEN(nbytes) > resp->end);		\
1753 } while (0)
1754 #define ADJUST_ARGS()		resp->p = p
1755 
1756 /* Encode as an array of strings the string given with components
1757  * separated @sep, escaped with esc_enter and esc_exit.
1758  */
1759 static __be32 nfsd4_encode_components_esc(char sep, char *components,
1760 				   __be32 **pp, int *buflen,
1761 				   char esc_enter, char esc_exit)
1762 {
1763 	__be32 *p = *pp;
1764 	__be32 *countp = p;
1765 	int strlen, count=0;
1766 	char *str, *end, *next;
1767 
1768 	dprintk("nfsd4_encode_components(%s)\n", components);
1769 	if ((*buflen -= 4) < 0)
1770 		return nfserr_resource;
1771 	WRITE32(0); /* We will fill this in with @count later */
1772 	end = str = components;
1773 	while (*end) {
1774 		bool found_esc = false;
1775 
1776 		/* try to parse as esc_start, ..., esc_end, sep */
1777 		if (*str == esc_enter) {
1778 			for (; *end && (*end != esc_exit); end++)
1779 				/* find esc_exit or end of string */;
1780 			next = end + 1;
1781 			if (*end && (!*next || *next == sep)) {
1782 				str++;
1783 				found_esc = true;
1784 			}
1785 		}
1786 
1787 		if (!found_esc)
1788 			for (; *end && (*end != sep); end++)
1789 				/* find sep or end of string */;
1790 
1791 		strlen = end - str;
1792 		if (strlen) {
1793 			if ((*buflen -= ((XDR_QUADLEN(strlen) << 2) + 4)) < 0)
1794 				return nfserr_resource;
1795 			WRITE32(strlen);
1796 			WRITEMEM(str, strlen);
1797 			count++;
1798 		}
1799 		else
1800 			end++;
1801 		str = end;
1802 	}
1803 	*pp = p;
1804 	p = countp;
1805 	WRITE32(count);
1806 	return 0;
1807 }
1808 
1809 /* Encode as an array of strings the string given with components
1810  * separated @sep.
1811  */
1812 static __be32 nfsd4_encode_components(char sep, char *components,
1813 				   __be32 **pp, int *buflen)
1814 {
1815 	return nfsd4_encode_components_esc(sep, components, pp, buflen, 0, 0);
1816 }
1817 
1818 /*
1819  * encode a location element of a fs_locations structure
1820  */
1821 static __be32 nfsd4_encode_fs_location4(struct nfsd4_fs_location *location,
1822 				    __be32 **pp, int *buflen)
1823 {
1824 	__be32 status;
1825 	__be32 *p = *pp;
1826 
1827 	status = nfsd4_encode_components_esc(':', location->hosts, &p, buflen,
1828 						'[', ']');
1829 	if (status)
1830 		return status;
1831 	status = nfsd4_encode_components('/', location->path, &p, buflen);
1832 	if (status)
1833 		return status;
1834 	*pp = p;
1835 	return 0;
1836 }
1837 
1838 /*
1839  * Encode a path in RFC3530 'pathname4' format
1840  */
1841 static __be32 nfsd4_encode_path(const struct path *root,
1842 		const struct path *path, __be32 **pp, int *buflen)
1843 {
1844 	struct path cur = *path;
1845 	__be32 *p = *pp;
1846 	struct dentry **components = NULL;
1847 	unsigned int ncomponents = 0;
1848 	__be32 err = nfserr_jukebox;
1849 
1850 	dprintk("nfsd4_encode_components(");
1851 
1852 	path_get(&cur);
1853 	/* First walk the path up to the nfsd root, and store the
1854 	 * dentries/path components in an array.
1855 	 */
1856 	for (;;) {
1857 		if (cur.dentry == root->dentry && cur.mnt == root->mnt)
1858 			break;
1859 		if (cur.dentry == cur.mnt->mnt_root) {
1860 			if (follow_up(&cur))
1861 				continue;
1862 			goto out_free;
1863 		}
1864 		if ((ncomponents & 15) == 0) {
1865 			struct dentry **new;
1866 			new = krealloc(components,
1867 					sizeof(*new) * (ncomponents + 16),
1868 					GFP_KERNEL);
1869 			if (!new)
1870 				goto out_free;
1871 			components = new;
1872 		}
1873 		components[ncomponents++] = cur.dentry;
1874 		cur.dentry = dget_parent(cur.dentry);
1875 	}
1876 
1877 	*buflen -= 4;
1878 	if (*buflen < 0)
1879 		goto out_free;
1880 	WRITE32(ncomponents);
1881 
1882 	while (ncomponents) {
1883 		struct dentry *dentry = components[ncomponents - 1];
1884 		unsigned int len;
1885 
1886 		spin_lock(&dentry->d_lock);
1887 		len = dentry->d_name.len;
1888 		*buflen -= 4 + (XDR_QUADLEN(len) << 2);
1889 		if (*buflen < 0) {
1890 			spin_unlock(&dentry->d_lock);
1891 			goto out_free;
1892 		}
1893 		WRITE32(len);
1894 		WRITEMEM(dentry->d_name.name, len);
1895 		dprintk("/%s", dentry->d_name.name);
1896 		spin_unlock(&dentry->d_lock);
1897 		dput(dentry);
1898 		ncomponents--;
1899 	}
1900 
1901 	*pp = p;
1902 	err = 0;
1903 out_free:
1904 	dprintk(")\n");
1905 	while (ncomponents)
1906 		dput(components[--ncomponents]);
1907 	kfree(components);
1908 	path_put(&cur);
1909 	return err;
1910 }
1911 
1912 static __be32 nfsd4_encode_fsloc_fsroot(struct svc_rqst *rqstp,
1913 		const struct path *path, __be32 **pp, int *buflen)
1914 {
1915 	struct svc_export *exp_ps;
1916 	__be32 res;
1917 
1918 	exp_ps = rqst_find_fsidzero_export(rqstp);
1919 	if (IS_ERR(exp_ps))
1920 		return nfserrno(PTR_ERR(exp_ps));
1921 	res = nfsd4_encode_path(&exp_ps->ex_path, path, pp, buflen);
1922 	exp_put(exp_ps);
1923 	return res;
1924 }
1925 
1926 /*
1927  *  encode a fs_locations structure
1928  */
1929 static __be32 nfsd4_encode_fs_locations(struct svc_rqst *rqstp,
1930 				     struct svc_export *exp,
1931 				     __be32 **pp, int *buflen)
1932 {
1933 	__be32 status;
1934 	int i;
1935 	__be32 *p = *pp;
1936 	struct nfsd4_fs_locations *fslocs = &exp->ex_fslocs;
1937 
1938 	status = nfsd4_encode_fsloc_fsroot(rqstp, &exp->ex_path, &p, buflen);
1939 	if (status)
1940 		return status;
1941 	if ((*buflen -= 4) < 0)
1942 		return nfserr_resource;
1943 	WRITE32(fslocs->locations_count);
1944 	for (i=0; i<fslocs->locations_count; i++) {
1945 		status = nfsd4_encode_fs_location4(&fslocs->locations[i],
1946 						   &p, buflen);
1947 		if (status)
1948 			return status;
1949 	}
1950 	*pp = p;
1951 	return 0;
1952 }
1953 
1954 static u32 nfs4_file_type(umode_t mode)
1955 {
1956 	switch (mode & S_IFMT) {
1957 	case S_IFIFO:	return NF4FIFO;
1958 	case S_IFCHR:	return NF4CHR;
1959 	case S_IFDIR:	return NF4DIR;
1960 	case S_IFBLK:	return NF4BLK;
1961 	case S_IFLNK:	return NF4LNK;
1962 	case S_IFREG:	return NF4REG;
1963 	case S_IFSOCK:	return NF4SOCK;
1964 	default:	return NF4BAD;
1965 	};
1966 }
1967 
1968 static inline __be32
1969 nfsd4_encode_aclname(struct svc_rqst *rqstp, struct nfs4_ace *ace,
1970 		__be32 **p, int *buflen)
1971 {
1972 	if (ace->whotype != NFS4_ACL_WHO_NAMED)
1973 		return nfs4_acl_write_who(ace->whotype, p, buflen);
1974 	else if (ace->flag & NFS4_ACE_IDENTIFIER_GROUP)
1975 		return nfsd4_encode_group(rqstp, ace->who_gid, p, buflen);
1976 	else
1977 		return nfsd4_encode_user(rqstp, ace->who_uid, p, buflen);
1978 }
1979 
1980 #define WORD0_ABSENT_FS_ATTRS (FATTR4_WORD0_FS_LOCATIONS | FATTR4_WORD0_FSID | \
1981 			      FATTR4_WORD0_RDATTR_ERROR)
1982 #define WORD1_ABSENT_FS_ATTRS FATTR4_WORD1_MOUNTED_ON_FILEID
1983 
1984 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
1985 static inline __be32
1986 nfsd4_encode_security_label(struct svc_rqst *rqstp, void *context, int len, __be32 **pp, int *buflen)
1987 {
1988 	__be32 *p = *pp;
1989 
1990 	if (*buflen < ((XDR_QUADLEN(len) << 2) + 4 + 4 + 4))
1991 		return nfserr_resource;
1992 
1993 	/*
1994 	 * For now we use a 0 here to indicate the null translation; in
1995 	 * the future we may place a call to translation code here.
1996 	 */
1997 	if ((*buflen -= 8) < 0)
1998 		return nfserr_resource;
1999 
2000 	WRITE32(0); /* lfs */
2001 	WRITE32(0); /* pi */
2002 	p = xdr_encode_opaque(p, context, len);
2003 	*buflen -= (XDR_QUADLEN(len) << 2) + 4;
2004 
2005 	*pp = p;
2006 	return 0;
2007 }
2008 #else
2009 static inline __be32
2010 nfsd4_encode_security_label(struct svc_rqst *rqstp, void *context, int len, __be32 **pp, int *buflen)
2011 { return 0; }
2012 #endif
2013 
2014 static __be32 fattr_handle_absent_fs(u32 *bmval0, u32 *bmval1, u32 *rdattr_err)
2015 {
2016 	/* As per referral draft:  */
2017 	if (*bmval0 & ~WORD0_ABSENT_FS_ATTRS ||
2018 	    *bmval1 & ~WORD1_ABSENT_FS_ATTRS) {
2019 		if (*bmval0 & FATTR4_WORD0_RDATTR_ERROR ||
2020 	            *bmval0 & FATTR4_WORD0_FS_LOCATIONS)
2021 			*rdattr_err = NFSERR_MOVED;
2022 		else
2023 			return nfserr_moved;
2024 	}
2025 	*bmval0 &= WORD0_ABSENT_FS_ATTRS;
2026 	*bmval1 &= WORD1_ABSENT_FS_ATTRS;
2027 	return 0;
2028 }
2029 
2030 
2031 static int get_parent_attributes(struct svc_export *exp, struct kstat *stat)
2032 {
2033 	struct path path = exp->ex_path;
2034 	int err;
2035 
2036 	path_get(&path);
2037 	while (follow_up(&path)) {
2038 		if (path.dentry != path.mnt->mnt_root)
2039 			break;
2040 	}
2041 	err = vfs_getattr(&path, stat);
2042 	path_put(&path);
2043 	return err;
2044 }
2045 
2046 /*
2047  * Note: @fhp can be NULL; in this case, we might have to compose the filehandle
2048  * ourselves.
2049  *
2050  * countp is the buffer size in _words_
2051  */
2052 __be32
2053 nfsd4_encode_fattr(struct svc_fh *fhp, struct svc_export *exp,
2054 		struct dentry *dentry, __be32 **buffer, int count, u32 *bmval,
2055 		struct svc_rqst *rqstp, int ignore_crossmnt)
2056 {
2057 	u32 bmval0 = bmval[0];
2058 	u32 bmval1 = bmval[1];
2059 	u32 bmval2 = bmval[2];
2060 	struct kstat stat;
2061 	struct svc_fh *tempfh = NULL;
2062 	struct kstatfs statfs;
2063 	int buflen = count << 2;
2064 	__be32 *attrlenp;
2065 	u32 dummy;
2066 	u64 dummy64;
2067 	u32 rdattr_err = 0;
2068 	__be32 *p = *buffer;
2069 	__be32 status;
2070 	int err;
2071 	int aclsupport = 0;
2072 	struct nfs4_acl *acl = NULL;
2073 	void *context = NULL;
2074 	int contextlen;
2075 	bool contextsupport = false;
2076 	struct nfsd4_compoundres *resp = rqstp->rq_resp;
2077 	u32 minorversion = resp->cstate.minorversion;
2078 	struct path path = {
2079 		.mnt	= exp->ex_path.mnt,
2080 		.dentry	= dentry,
2081 	};
2082 	struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
2083 
2084 	BUG_ON(bmval1 & NFSD_WRITEONLY_ATTRS_WORD1);
2085 	BUG_ON(bmval0 & ~nfsd_suppattrs0(minorversion));
2086 	BUG_ON(bmval1 & ~nfsd_suppattrs1(minorversion));
2087 	BUG_ON(bmval2 & ~nfsd_suppattrs2(minorversion));
2088 
2089 	if (exp->ex_fslocs.migrated) {
2090 		BUG_ON(bmval[2]);
2091 		status = fattr_handle_absent_fs(&bmval0, &bmval1, &rdattr_err);
2092 		if (status)
2093 			goto out;
2094 	}
2095 
2096 	err = vfs_getattr(&path, &stat);
2097 	if (err)
2098 		goto out_nfserr;
2099 	if ((bmval0 & (FATTR4_WORD0_FILES_FREE | FATTR4_WORD0_FILES_TOTAL |
2100 			FATTR4_WORD0_MAXNAME)) ||
2101 	    (bmval1 & (FATTR4_WORD1_SPACE_AVAIL | FATTR4_WORD1_SPACE_FREE |
2102 		       FATTR4_WORD1_SPACE_TOTAL))) {
2103 		err = vfs_statfs(&path, &statfs);
2104 		if (err)
2105 			goto out_nfserr;
2106 	}
2107 	if ((bmval0 & (FATTR4_WORD0_FILEHANDLE | FATTR4_WORD0_FSID)) && !fhp) {
2108 		tempfh = kmalloc(sizeof(struct svc_fh), GFP_KERNEL);
2109 		status = nfserr_jukebox;
2110 		if (!tempfh)
2111 			goto out;
2112 		fh_init(tempfh, NFS4_FHSIZE);
2113 		status = fh_compose(tempfh, exp, dentry, NULL);
2114 		if (status)
2115 			goto out;
2116 		fhp = tempfh;
2117 	}
2118 	if (bmval0 & (FATTR4_WORD0_ACL | FATTR4_WORD0_ACLSUPPORT
2119 			| FATTR4_WORD0_SUPPORTED_ATTRS)) {
2120 		err = nfsd4_get_nfs4_acl(rqstp, dentry, &acl);
2121 		aclsupport = (err == 0);
2122 		if (bmval0 & FATTR4_WORD0_ACL) {
2123 			if (err == -EOPNOTSUPP)
2124 				bmval0 &= ~FATTR4_WORD0_ACL;
2125 			else if (err == -EINVAL) {
2126 				status = nfserr_attrnotsupp;
2127 				goto out;
2128 			} else if (err != 0)
2129 				goto out_nfserr;
2130 		}
2131 	}
2132 
2133 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2134 	if ((bmval[2] & FATTR4_WORD2_SECURITY_LABEL) ||
2135 			bmval[0] & FATTR4_WORD0_SUPPORTED_ATTRS) {
2136 		err = security_inode_getsecctx(dentry->d_inode,
2137 						&context, &contextlen);
2138 		contextsupport = (err == 0);
2139 		if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2140 			if (err == -EOPNOTSUPP)
2141 				bmval2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2142 			else if (err)
2143 				goto out_nfserr;
2144 		}
2145 	}
2146 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2147 
2148 	if (bmval2) {
2149 		if ((buflen -= 16) < 0)
2150 			goto out_resource;
2151 		WRITE32(3);
2152 		WRITE32(bmval0);
2153 		WRITE32(bmval1);
2154 		WRITE32(bmval2);
2155 	} else if (bmval1) {
2156 		if ((buflen -= 12) < 0)
2157 			goto out_resource;
2158 		WRITE32(2);
2159 		WRITE32(bmval0);
2160 		WRITE32(bmval1);
2161 	} else {
2162 		if ((buflen -= 8) < 0)
2163 			goto out_resource;
2164 		WRITE32(1);
2165 		WRITE32(bmval0);
2166 	}
2167 	attrlenp = p++;                /* to be backfilled later */
2168 
2169 	if (bmval0 & FATTR4_WORD0_SUPPORTED_ATTRS) {
2170 		u32 word0 = nfsd_suppattrs0(minorversion);
2171 		u32 word1 = nfsd_suppattrs1(minorversion);
2172 		u32 word2 = nfsd_suppattrs2(minorversion);
2173 
2174 		if (!aclsupport)
2175 			word0 &= ~FATTR4_WORD0_ACL;
2176 		if (!contextsupport)
2177 			word2 &= ~FATTR4_WORD2_SECURITY_LABEL;
2178 		if (!word2) {
2179 			if ((buflen -= 12) < 0)
2180 				goto out_resource;
2181 			WRITE32(2);
2182 			WRITE32(word0);
2183 			WRITE32(word1);
2184 		} else {
2185 			if ((buflen -= 16) < 0)
2186 				goto out_resource;
2187 			WRITE32(3);
2188 			WRITE32(word0);
2189 			WRITE32(word1);
2190 			WRITE32(word2);
2191 		}
2192 	}
2193 	if (bmval0 & FATTR4_WORD0_TYPE) {
2194 		if ((buflen -= 4) < 0)
2195 			goto out_resource;
2196 		dummy = nfs4_file_type(stat.mode);
2197 		if (dummy == NF4BAD) {
2198 			status = nfserr_serverfault;
2199 			goto out;
2200 		}
2201 		WRITE32(dummy);
2202 	}
2203 	if (bmval0 & FATTR4_WORD0_FH_EXPIRE_TYPE) {
2204 		if ((buflen -= 4) < 0)
2205 			goto out_resource;
2206 		if (exp->ex_flags & NFSEXP_NOSUBTREECHECK)
2207 			WRITE32(NFS4_FH_PERSISTENT);
2208 		else
2209 			WRITE32(NFS4_FH_PERSISTENT|NFS4_FH_VOL_RENAME);
2210 	}
2211 	if (bmval0 & FATTR4_WORD0_CHANGE) {
2212 		if ((buflen -= 8) < 0)
2213 			goto out_resource;
2214 		write_change(&p, &stat, dentry->d_inode);
2215 	}
2216 	if (bmval0 & FATTR4_WORD0_SIZE) {
2217 		if ((buflen -= 8) < 0)
2218 			goto out_resource;
2219 		WRITE64(stat.size);
2220 	}
2221 	if (bmval0 & FATTR4_WORD0_LINK_SUPPORT) {
2222 		if ((buflen -= 4) < 0)
2223 			goto out_resource;
2224 		WRITE32(1);
2225 	}
2226 	if (bmval0 & FATTR4_WORD0_SYMLINK_SUPPORT) {
2227 		if ((buflen -= 4) < 0)
2228 			goto out_resource;
2229 		WRITE32(1);
2230 	}
2231 	if (bmval0 & FATTR4_WORD0_NAMED_ATTR) {
2232 		if ((buflen -= 4) < 0)
2233 			goto out_resource;
2234 		WRITE32(0);
2235 	}
2236 	if (bmval0 & FATTR4_WORD0_FSID) {
2237 		if ((buflen -= 16) < 0)
2238 			goto out_resource;
2239 		if (exp->ex_fslocs.migrated) {
2240 			WRITE64(NFS4_REFERRAL_FSID_MAJOR);
2241 			WRITE64(NFS4_REFERRAL_FSID_MINOR);
2242 		} else switch(fsid_source(fhp)) {
2243 		case FSIDSOURCE_FSID:
2244 			WRITE64((u64)exp->ex_fsid);
2245 			WRITE64((u64)0);
2246 			break;
2247 		case FSIDSOURCE_DEV:
2248 			WRITE32(0);
2249 			WRITE32(MAJOR(stat.dev));
2250 			WRITE32(0);
2251 			WRITE32(MINOR(stat.dev));
2252 			break;
2253 		case FSIDSOURCE_UUID:
2254 			WRITEMEM(exp->ex_uuid, 16);
2255 			break;
2256 		}
2257 	}
2258 	if (bmval0 & FATTR4_WORD0_UNIQUE_HANDLES) {
2259 		if ((buflen -= 4) < 0)
2260 			goto out_resource;
2261 		WRITE32(0);
2262 	}
2263 	if (bmval0 & FATTR4_WORD0_LEASE_TIME) {
2264 		if ((buflen -= 4) < 0)
2265 			goto out_resource;
2266 		WRITE32(nn->nfsd4_lease);
2267 	}
2268 	if (bmval0 & FATTR4_WORD0_RDATTR_ERROR) {
2269 		if ((buflen -= 4) < 0)
2270 			goto out_resource;
2271 		WRITE32(rdattr_err);
2272 	}
2273 	if (bmval0 & FATTR4_WORD0_ACL) {
2274 		struct nfs4_ace *ace;
2275 
2276 		if (acl == NULL) {
2277 			if ((buflen -= 4) < 0)
2278 				goto out_resource;
2279 
2280 			WRITE32(0);
2281 			goto out_acl;
2282 		}
2283 		if ((buflen -= 4) < 0)
2284 			goto out_resource;
2285 		WRITE32(acl->naces);
2286 
2287 		for (ace = acl->aces; ace < acl->aces + acl->naces; ace++) {
2288 			if ((buflen -= 4*3) < 0)
2289 				goto out_resource;
2290 			WRITE32(ace->type);
2291 			WRITE32(ace->flag);
2292 			WRITE32(ace->access_mask & NFS4_ACE_MASK_ALL);
2293 			status = nfsd4_encode_aclname(rqstp, ace, &p, &buflen);
2294 			if (status)
2295 				goto out;
2296 		}
2297 	}
2298 out_acl:
2299 	if (bmval0 & FATTR4_WORD0_ACLSUPPORT) {
2300 		if ((buflen -= 4) < 0)
2301 			goto out_resource;
2302 		WRITE32(aclsupport ?
2303 			ACL4_SUPPORT_ALLOW_ACL|ACL4_SUPPORT_DENY_ACL : 0);
2304 	}
2305 	if (bmval0 & FATTR4_WORD0_CANSETTIME) {
2306 		if ((buflen -= 4) < 0)
2307 			goto out_resource;
2308 		WRITE32(1);
2309 	}
2310 	if (bmval0 & FATTR4_WORD0_CASE_INSENSITIVE) {
2311 		if ((buflen -= 4) < 0)
2312 			goto out_resource;
2313 		WRITE32(0);
2314 	}
2315 	if (bmval0 & FATTR4_WORD0_CASE_PRESERVING) {
2316 		if ((buflen -= 4) < 0)
2317 			goto out_resource;
2318 		WRITE32(1);
2319 	}
2320 	if (bmval0 & FATTR4_WORD0_CHOWN_RESTRICTED) {
2321 		if ((buflen -= 4) < 0)
2322 			goto out_resource;
2323 		WRITE32(1);
2324 	}
2325 	if (bmval0 & FATTR4_WORD0_FILEHANDLE) {
2326 		buflen -= (XDR_QUADLEN(fhp->fh_handle.fh_size) << 2) + 4;
2327 		if (buflen < 0)
2328 			goto out_resource;
2329 		WRITE32(fhp->fh_handle.fh_size);
2330 		WRITEMEM(&fhp->fh_handle.fh_base, fhp->fh_handle.fh_size);
2331 	}
2332 	if (bmval0 & FATTR4_WORD0_FILEID) {
2333 		if ((buflen -= 8) < 0)
2334 			goto out_resource;
2335 		WRITE64(stat.ino);
2336 	}
2337 	if (bmval0 & FATTR4_WORD0_FILES_AVAIL) {
2338 		if ((buflen -= 8) < 0)
2339 			goto out_resource;
2340 		WRITE64((u64) statfs.f_ffree);
2341 	}
2342 	if (bmval0 & FATTR4_WORD0_FILES_FREE) {
2343 		if ((buflen -= 8) < 0)
2344 			goto out_resource;
2345 		WRITE64((u64) statfs.f_ffree);
2346 	}
2347 	if (bmval0 & FATTR4_WORD0_FILES_TOTAL) {
2348 		if ((buflen -= 8) < 0)
2349 			goto out_resource;
2350 		WRITE64((u64) statfs.f_files);
2351 	}
2352 	if (bmval0 & FATTR4_WORD0_FS_LOCATIONS) {
2353 		status = nfsd4_encode_fs_locations(rqstp, exp, &p, &buflen);
2354 		if (status)
2355 			goto out;
2356 	}
2357 	if (bmval0 & FATTR4_WORD0_HOMOGENEOUS) {
2358 		if ((buflen -= 4) < 0)
2359 			goto out_resource;
2360 		WRITE32(1);
2361 	}
2362 	if (bmval0 & FATTR4_WORD0_MAXFILESIZE) {
2363 		if ((buflen -= 8) < 0)
2364 			goto out_resource;
2365 		WRITE64(exp->ex_path.mnt->mnt_sb->s_maxbytes);
2366 	}
2367 	if (bmval0 & FATTR4_WORD0_MAXLINK) {
2368 		if ((buflen -= 4) < 0)
2369 			goto out_resource;
2370 		WRITE32(255);
2371 	}
2372 	if (bmval0 & FATTR4_WORD0_MAXNAME) {
2373 		if ((buflen -= 4) < 0)
2374 			goto out_resource;
2375 		WRITE32(statfs.f_namelen);
2376 	}
2377 	if (bmval0 & FATTR4_WORD0_MAXREAD) {
2378 		if ((buflen -= 8) < 0)
2379 			goto out_resource;
2380 		WRITE64((u64) svc_max_payload(rqstp));
2381 	}
2382 	if (bmval0 & FATTR4_WORD0_MAXWRITE) {
2383 		if ((buflen -= 8) < 0)
2384 			goto out_resource;
2385 		WRITE64((u64) svc_max_payload(rqstp));
2386 	}
2387 	if (bmval1 & FATTR4_WORD1_MODE) {
2388 		if ((buflen -= 4) < 0)
2389 			goto out_resource;
2390 		WRITE32(stat.mode & S_IALLUGO);
2391 	}
2392 	if (bmval1 & FATTR4_WORD1_NO_TRUNC) {
2393 		if ((buflen -= 4) < 0)
2394 			goto out_resource;
2395 		WRITE32(1);
2396 	}
2397 	if (bmval1 & FATTR4_WORD1_NUMLINKS) {
2398 		if ((buflen -= 4) < 0)
2399 			goto out_resource;
2400 		WRITE32(stat.nlink);
2401 	}
2402 	if (bmval1 & FATTR4_WORD1_OWNER) {
2403 		status = nfsd4_encode_user(rqstp, stat.uid, &p, &buflen);
2404 		if (status)
2405 			goto out;
2406 	}
2407 	if (bmval1 & FATTR4_WORD1_OWNER_GROUP) {
2408 		status = nfsd4_encode_group(rqstp, stat.gid, &p, &buflen);
2409 		if (status)
2410 			goto out;
2411 	}
2412 	if (bmval1 & FATTR4_WORD1_RAWDEV) {
2413 		if ((buflen -= 8) < 0)
2414 			goto out_resource;
2415 		WRITE32((u32) MAJOR(stat.rdev));
2416 		WRITE32((u32) MINOR(stat.rdev));
2417 	}
2418 	if (bmval1 & FATTR4_WORD1_SPACE_AVAIL) {
2419 		if ((buflen -= 8) < 0)
2420 			goto out_resource;
2421 		dummy64 = (u64)statfs.f_bavail * (u64)statfs.f_bsize;
2422 		WRITE64(dummy64);
2423 	}
2424 	if (bmval1 & FATTR4_WORD1_SPACE_FREE) {
2425 		if ((buflen -= 8) < 0)
2426 			goto out_resource;
2427 		dummy64 = (u64)statfs.f_bfree * (u64)statfs.f_bsize;
2428 		WRITE64(dummy64);
2429 	}
2430 	if (bmval1 & FATTR4_WORD1_SPACE_TOTAL) {
2431 		if ((buflen -= 8) < 0)
2432 			goto out_resource;
2433 		dummy64 = (u64)statfs.f_blocks * (u64)statfs.f_bsize;
2434 		WRITE64(dummy64);
2435 	}
2436 	if (bmval1 & FATTR4_WORD1_SPACE_USED) {
2437 		if ((buflen -= 8) < 0)
2438 			goto out_resource;
2439 		dummy64 = (u64)stat.blocks << 9;
2440 		WRITE64(dummy64);
2441 	}
2442 	if (bmval1 & FATTR4_WORD1_TIME_ACCESS) {
2443 		if ((buflen -= 12) < 0)
2444 			goto out_resource;
2445 		WRITE64((s64)stat.atime.tv_sec);
2446 		WRITE32(stat.atime.tv_nsec);
2447 	}
2448 	if (bmval1 & FATTR4_WORD1_TIME_DELTA) {
2449 		if ((buflen -= 12) < 0)
2450 			goto out_resource;
2451 		WRITE32(0);
2452 		WRITE32(1);
2453 		WRITE32(0);
2454 	}
2455 	if (bmval1 & FATTR4_WORD1_TIME_METADATA) {
2456 		if ((buflen -= 12) < 0)
2457 			goto out_resource;
2458 		WRITE64((s64)stat.ctime.tv_sec);
2459 		WRITE32(stat.ctime.tv_nsec);
2460 	}
2461 	if (bmval1 & FATTR4_WORD1_TIME_MODIFY) {
2462 		if ((buflen -= 12) < 0)
2463 			goto out_resource;
2464 		WRITE64((s64)stat.mtime.tv_sec);
2465 		WRITE32(stat.mtime.tv_nsec);
2466 	}
2467 	if (bmval1 & FATTR4_WORD1_MOUNTED_ON_FILEID) {
2468 		if ((buflen -= 8) < 0)
2469                 	goto out_resource;
2470 		/*
2471 		 * Get parent's attributes if not ignoring crossmount
2472 		 * and this is the root of a cross-mounted filesystem.
2473 		 */
2474 		if (ignore_crossmnt == 0 &&
2475 		    dentry == exp->ex_path.mnt->mnt_root)
2476 			get_parent_attributes(exp, &stat);
2477 		WRITE64(stat.ino);
2478 	}
2479 	if (bmval2 & FATTR4_WORD2_SECURITY_LABEL) {
2480 		status = nfsd4_encode_security_label(rqstp, context,
2481 				contextlen, &p, &buflen);
2482 		if (status)
2483 			goto out;
2484 	}
2485 	if (bmval2 & FATTR4_WORD2_SUPPATTR_EXCLCREAT) {
2486 		WRITE32(3);
2487 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD0);
2488 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD1);
2489 		WRITE32(NFSD_SUPPATTR_EXCLCREAT_WORD2);
2490 	}
2491 
2492 	*attrlenp = htonl((char *)p - (char *)attrlenp - 4);
2493 	*buffer = p;
2494 	status = nfs_ok;
2495 
2496 out:
2497 #ifdef CONFIG_NFSD_V4_SECURITY_LABEL
2498 	if (context)
2499 		security_release_secctx(context, contextlen);
2500 #endif /* CONFIG_NFSD_V4_SECURITY_LABEL */
2501 	kfree(acl);
2502 	if (tempfh)
2503 		fh_put(tempfh);
2504 	return status;
2505 out_nfserr:
2506 	status = nfserrno(err);
2507 	goto out;
2508 out_resource:
2509 	status = nfserr_resource;
2510 	goto out;
2511 }
2512 
2513 static inline int attributes_need_mount(u32 *bmval)
2514 {
2515 	if (bmval[0] & ~(FATTR4_WORD0_RDATTR_ERROR | FATTR4_WORD0_LEASE_TIME))
2516 		return 1;
2517 	if (bmval[1] & ~FATTR4_WORD1_MOUNTED_ON_FILEID)
2518 		return 1;
2519 	return 0;
2520 }
2521 
2522 static __be32
2523 nfsd4_encode_dirent_fattr(struct nfsd4_readdir *cd,
2524 		const char *name, int namlen, __be32 **p, int buflen)
2525 {
2526 	struct svc_export *exp = cd->rd_fhp->fh_export;
2527 	struct dentry *dentry;
2528 	__be32 nfserr;
2529 	int ignore_crossmnt = 0;
2530 
2531 	dentry = lookup_one_len(name, cd->rd_fhp->fh_dentry, namlen);
2532 	if (IS_ERR(dentry))
2533 		return nfserrno(PTR_ERR(dentry));
2534 	if (!dentry->d_inode) {
2535 		/*
2536 		 * nfsd_buffered_readdir drops the i_mutex between
2537 		 * readdir and calling this callback, leaving a window
2538 		 * where this directory entry could have gone away.
2539 		 */
2540 		dput(dentry);
2541 		return nfserr_noent;
2542 	}
2543 
2544 	exp_get(exp);
2545 	/*
2546 	 * In the case of a mountpoint, the client may be asking for
2547 	 * attributes that are only properties of the underlying filesystem
2548 	 * as opposed to the cross-mounted file system. In such a case,
2549 	 * we will not follow the cross mount and will fill the attribtutes
2550 	 * directly from the mountpoint dentry.
2551 	 */
2552 	if (nfsd_mountpoint(dentry, exp)) {
2553 		int err;
2554 
2555 		if (!(exp->ex_flags & NFSEXP_V4ROOT)
2556 				&& !attributes_need_mount(cd->rd_bmval)) {
2557 			ignore_crossmnt = 1;
2558 			goto out_encode;
2559 		}
2560 		/*
2561 		 * Why the heck aren't we just using nfsd_lookup??
2562 		 * Different "."/".." handling?  Something else?
2563 		 * At least, add a comment here to explain....
2564 		 */
2565 		err = nfsd_cross_mnt(cd->rd_rqstp, &dentry, &exp);
2566 		if (err) {
2567 			nfserr = nfserrno(err);
2568 			goto out_put;
2569 		}
2570 		nfserr = check_nfsd_access(exp, cd->rd_rqstp);
2571 		if (nfserr)
2572 			goto out_put;
2573 
2574 	}
2575 out_encode:
2576 	nfserr = nfsd4_encode_fattr(NULL, exp, dentry, p, buflen, cd->rd_bmval,
2577 					cd->rd_rqstp, ignore_crossmnt);
2578 out_put:
2579 	dput(dentry);
2580 	exp_put(exp);
2581 	return nfserr;
2582 }
2583 
2584 static __be32 *
2585 nfsd4_encode_rdattr_error(__be32 *p, int buflen, __be32 nfserr)
2586 {
2587 	if (buflen < 6)
2588 		return NULL;
2589 	*p++ = htonl(2);
2590 	*p++ = htonl(FATTR4_WORD0_RDATTR_ERROR); /* bmval0 */
2591 	*p++ = htonl(0);			 /* bmval1 */
2592 
2593 	*p++ = htonl(4);     /* attribute length */
2594 	*p++ = nfserr;       /* no htonl */
2595 	return p;
2596 }
2597 
2598 static int
2599 nfsd4_encode_dirent(void *ccdv, const char *name, int namlen,
2600 		    loff_t offset, u64 ino, unsigned int d_type)
2601 {
2602 	struct readdir_cd *ccd = ccdv;
2603 	struct nfsd4_readdir *cd = container_of(ccd, struct nfsd4_readdir, common);
2604 	int buflen;
2605 	__be32 *p = cd->buffer;
2606 	__be32 *cookiep;
2607 	__be32 nfserr = nfserr_toosmall;
2608 
2609 	/* In nfsv4, "." and ".." never make it onto the wire.. */
2610 	if (name && isdotent(name, namlen)) {
2611 		cd->common.err = nfs_ok;
2612 		return 0;
2613 	}
2614 
2615 	if (cd->offset)
2616 		xdr_encode_hyper(cd->offset, (u64) offset);
2617 
2618 	buflen = cd->buflen - 4 - XDR_QUADLEN(namlen);
2619 	if (buflen < 0)
2620 		goto fail;
2621 
2622 	*p++ = xdr_one;                             /* mark entry present */
2623 	cookiep = p;
2624 	p = xdr_encode_hyper(p, NFS_OFFSET_MAX);    /* offset of next entry */
2625 	p = xdr_encode_array(p, name, namlen);      /* name length & name */
2626 
2627 	nfserr = nfsd4_encode_dirent_fattr(cd, name, namlen, &p, buflen);
2628 	switch (nfserr) {
2629 	case nfs_ok:
2630 		break;
2631 	case nfserr_resource:
2632 		nfserr = nfserr_toosmall;
2633 		goto fail;
2634 	case nfserr_noent:
2635 		goto skip_entry;
2636 	default:
2637 		/*
2638 		 * If the client requested the RDATTR_ERROR attribute,
2639 		 * we stuff the error code into this attribute
2640 		 * and continue.  If this attribute was not requested,
2641 		 * then in accordance with the spec, we fail the
2642 		 * entire READDIR operation(!)
2643 		 */
2644 		if (!(cd->rd_bmval[0] & FATTR4_WORD0_RDATTR_ERROR))
2645 			goto fail;
2646 		p = nfsd4_encode_rdattr_error(p, buflen, nfserr);
2647 		if (p == NULL) {
2648 			nfserr = nfserr_toosmall;
2649 			goto fail;
2650 		}
2651 	}
2652 	cd->buflen -= (p - cd->buffer);
2653 	cd->buffer = p;
2654 	cd->offset = cookiep;
2655 skip_entry:
2656 	cd->common.err = nfs_ok;
2657 	return 0;
2658 fail:
2659 	cd->common.err = nfserr;
2660 	return -EINVAL;
2661 }
2662 
2663 static void
2664 nfsd4_encode_stateid(struct nfsd4_compoundres *resp, stateid_t *sid)
2665 {
2666 	__be32 *p;
2667 
2668 	RESERVE_SPACE(sizeof(stateid_t));
2669 	WRITE32(sid->si_generation);
2670 	WRITEMEM(&sid->si_opaque, sizeof(stateid_opaque_t));
2671 	ADJUST_ARGS();
2672 }
2673 
2674 static __be32
2675 nfsd4_encode_access(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_access *access)
2676 {
2677 	__be32 *p;
2678 
2679 	if (!nfserr) {
2680 		RESERVE_SPACE(8);
2681 		WRITE32(access->ac_supported);
2682 		WRITE32(access->ac_resp_access);
2683 		ADJUST_ARGS();
2684 	}
2685 	return nfserr;
2686 }
2687 
2688 static __be32 nfsd4_encode_bind_conn_to_session(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_bind_conn_to_session *bcts)
2689 {
2690 	__be32 *p;
2691 
2692 	if (!nfserr) {
2693 		RESERVE_SPACE(NFS4_MAX_SESSIONID_LEN + 8);
2694 		WRITEMEM(bcts->sessionid.data, NFS4_MAX_SESSIONID_LEN);
2695 		WRITE32(bcts->dir);
2696 		/* Sorry, we do not yet support RDMA over 4.1: */
2697 		WRITE32(0);
2698 		ADJUST_ARGS();
2699 	}
2700 	return nfserr;
2701 }
2702 
2703 static __be32
2704 nfsd4_encode_close(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_close *close)
2705 {
2706 	if (!nfserr)
2707 		nfsd4_encode_stateid(resp, &close->cl_stateid);
2708 
2709 	return nfserr;
2710 }
2711 
2712 
2713 static __be32
2714 nfsd4_encode_commit(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_commit *commit)
2715 {
2716 	__be32 *p;
2717 
2718 	if (!nfserr) {
2719 		RESERVE_SPACE(NFS4_VERIFIER_SIZE);
2720 		WRITEMEM(commit->co_verf.data, NFS4_VERIFIER_SIZE);
2721 		ADJUST_ARGS();
2722 	}
2723 	return nfserr;
2724 }
2725 
2726 static __be32
2727 nfsd4_encode_create(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_create *create)
2728 {
2729 	__be32 *p;
2730 
2731 	if (!nfserr) {
2732 		RESERVE_SPACE(32);
2733 		write_cinfo(&p, &create->cr_cinfo);
2734 		WRITE32(2);
2735 		WRITE32(create->cr_bmval[0]);
2736 		WRITE32(create->cr_bmval[1]);
2737 		ADJUST_ARGS();
2738 	}
2739 	return nfserr;
2740 }
2741 
2742 static __be32
2743 nfsd4_encode_getattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_getattr *getattr)
2744 {
2745 	struct svc_fh *fhp = getattr->ga_fhp;
2746 	int buflen;
2747 
2748 	if (nfserr)
2749 		return nfserr;
2750 
2751 	buflen = resp->end - resp->p - (COMPOUND_ERR_SLACK_SPACE >> 2);
2752 	nfserr = nfsd4_encode_fattr(fhp, fhp->fh_export, fhp->fh_dentry,
2753 				    &resp->p, buflen, getattr->ga_bmval,
2754 				    resp->rqstp, 0);
2755 	return nfserr;
2756 }
2757 
2758 static __be32
2759 nfsd4_encode_getfh(struct nfsd4_compoundres *resp, __be32 nfserr, struct svc_fh **fhpp)
2760 {
2761 	struct svc_fh *fhp = *fhpp;
2762 	unsigned int len;
2763 	__be32 *p;
2764 
2765 	if (!nfserr) {
2766 		len = fhp->fh_handle.fh_size;
2767 		RESERVE_SPACE(len + 4);
2768 		WRITE32(len);
2769 		WRITEMEM(&fhp->fh_handle.fh_base, len);
2770 		ADJUST_ARGS();
2771 	}
2772 	return nfserr;
2773 }
2774 
2775 /*
2776 * Including all fields other than the name, a LOCK4denied structure requires
2777 *   8(clientid) + 4(namelen) + 8(offset) + 8(length) + 4(type) = 32 bytes.
2778 */
2779 static void
2780 nfsd4_encode_lock_denied(struct nfsd4_compoundres *resp, struct nfsd4_lock_denied *ld)
2781 {
2782 	struct xdr_netobj *conf = &ld->ld_owner;
2783 	__be32 *p;
2784 
2785 	RESERVE_SPACE(32 + XDR_LEN(conf->len));
2786 	WRITE64(ld->ld_start);
2787 	WRITE64(ld->ld_length);
2788 	WRITE32(ld->ld_type);
2789 	if (conf->len) {
2790 		WRITEMEM(&ld->ld_clientid, 8);
2791 		WRITE32(conf->len);
2792 		WRITEMEM(conf->data, conf->len);
2793 		kfree(conf->data);
2794 	}  else {  /* non - nfsv4 lock in conflict, no clientid nor owner */
2795 		WRITE64((u64)0); /* clientid */
2796 		WRITE32(0); /* length of owner name */
2797 	}
2798 	ADJUST_ARGS();
2799 }
2800 
2801 static __be32
2802 nfsd4_encode_lock(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lock *lock)
2803 {
2804 	if (!nfserr)
2805 		nfsd4_encode_stateid(resp, &lock->lk_resp_stateid);
2806 	else if (nfserr == nfserr_denied)
2807 		nfsd4_encode_lock_denied(resp, &lock->lk_denied);
2808 
2809 	return nfserr;
2810 }
2811 
2812 static __be32
2813 nfsd4_encode_lockt(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_lockt *lockt)
2814 {
2815 	if (nfserr == nfserr_denied)
2816 		nfsd4_encode_lock_denied(resp, &lockt->lt_denied);
2817 	return nfserr;
2818 }
2819 
2820 static __be32
2821 nfsd4_encode_locku(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_locku *locku)
2822 {
2823 	if (!nfserr)
2824 		nfsd4_encode_stateid(resp, &locku->lu_stateid);
2825 
2826 	return nfserr;
2827 }
2828 
2829 
2830 static __be32
2831 nfsd4_encode_link(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_link *link)
2832 {
2833 	__be32 *p;
2834 
2835 	if (!nfserr) {
2836 		RESERVE_SPACE(20);
2837 		write_cinfo(&p, &link->li_cinfo);
2838 		ADJUST_ARGS();
2839 	}
2840 	return nfserr;
2841 }
2842 
2843 
2844 static __be32
2845 nfsd4_encode_open(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open *open)
2846 {
2847 	__be32 *p;
2848 
2849 	if (nfserr)
2850 		goto out;
2851 
2852 	nfsd4_encode_stateid(resp, &open->op_stateid);
2853 	RESERVE_SPACE(40);
2854 	write_cinfo(&p, &open->op_cinfo);
2855 	WRITE32(open->op_rflags);
2856 	WRITE32(2);
2857 	WRITE32(open->op_bmval[0]);
2858 	WRITE32(open->op_bmval[1]);
2859 	WRITE32(open->op_delegate_type);
2860 	ADJUST_ARGS();
2861 
2862 	switch (open->op_delegate_type) {
2863 	case NFS4_OPEN_DELEGATE_NONE:
2864 		break;
2865 	case NFS4_OPEN_DELEGATE_READ:
2866 		nfsd4_encode_stateid(resp, &open->op_delegate_stateid);
2867 		RESERVE_SPACE(20);
2868 		WRITE32(open->op_recall);
2869 
2870 		/*
2871 		 * TODO: ACE's in delegations
2872 		 */
2873 		WRITE32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
2874 		WRITE32(0);
2875 		WRITE32(0);
2876 		WRITE32(0);   /* XXX: is NULL principal ok? */
2877 		ADJUST_ARGS();
2878 		break;
2879 	case NFS4_OPEN_DELEGATE_WRITE:
2880 		nfsd4_encode_stateid(resp, &open->op_delegate_stateid);
2881 		RESERVE_SPACE(32);
2882 		WRITE32(0);
2883 
2884 		/*
2885 		 * TODO: space_limit's in delegations
2886 		 */
2887 		WRITE32(NFS4_LIMIT_SIZE);
2888 		WRITE32(~(u32)0);
2889 		WRITE32(~(u32)0);
2890 
2891 		/*
2892 		 * TODO: ACE's in delegations
2893 		 */
2894 		WRITE32(NFS4_ACE_ACCESS_ALLOWED_ACE_TYPE);
2895 		WRITE32(0);
2896 		WRITE32(0);
2897 		WRITE32(0);   /* XXX: is NULL principal ok? */
2898 		ADJUST_ARGS();
2899 		break;
2900 	case NFS4_OPEN_DELEGATE_NONE_EXT: /* 4.1 */
2901 		switch (open->op_why_no_deleg) {
2902 		case WND4_CONTENTION:
2903 		case WND4_RESOURCE:
2904 			RESERVE_SPACE(8);
2905 			WRITE32(open->op_why_no_deleg);
2906 			WRITE32(0);	/* deleg signaling not supported yet */
2907 			break;
2908 		default:
2909 			RESERVE_SPACE(4);
2910 			WRITE32(open->op_why_no_deleg);
2911 		}
2912 		ADJUST_ARGS();
2913 		break;
2914 	default:
2915 		BUG();
2916 	}
2917 	/* XXX save filehandle here */
2918 out:
2919 	return nfserr;
2920 }
2921 
2922 static __be32
2923 nfsd4_encode_open_confirm(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_confirm *oc)
2924 {
2925 	if (!nfserr)
2926 		nfsd4_encode_stateid(resp, &oc->oc_resp_stateid);
2927 
2928 	return nfserr;
2929 }
2930 
2931 static __be32
2932 nfsd4_encode_open_downgrade(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_open_downgrade *od)
2933 {
2934 	if (!nfserr)
2935 		nfsd4_encode_stateid(resp, &od->od_stateid);
2936 
2937 	return nfserr;
2938 }
2939 
2940 static __be32
2941 nfsd4_encode_read(struct nfsd4_compoundres *resp, __be32 nfserr,
2942 		  struct nfsd4_read *read)
2943 {
2944 	u32 eof;
2945 	int v;
2946 	struct page *page;
2947 	unsigned long maxcount;
2948 	long len;
2949 	__be32 *p;
2950 
2951 	if (nfserr)
2952 		return nfserr;
2953 	if (resp->xbuf->page_len)
2954 		return nfserr_resource;
2955 
2956 	RESERVE_SPACE(8); /* eof flag and byte count */
2957 
2958 	maxcount = svc_max_payload(resp->rqstp);
2959 	if (maxcount > read->rd_length)
2960 		maxcount = read->rd_length;
2961 
2962 	len = maxcount;
2963 	v = 0;
2964 	while (len > 0) {
2965 		page = *(resp->rqstp->rq_next_page);
2966 		if (!page) { /* ran out of pages */
2967 			maxcount -= len;
2968 			break;
2969 		}
2970 		resp->rqstp->rq_vec[v].iov_base = page_address(page);
2971 		resp->rqstp->rq_vec[v].iov_len =
2972 			len < PAGE_SIZE ? len : PAGE_SIZE;
2973 		resp->rqstp->rq_next_page++;
2974 		v++;
2975 		len -= PAGE_SIZE;
2976 	}
2977 	read->rd_vlen = v;
2978 
2979 	nfserr = nfsd_read_file(read->rd_rqstp, read->rd_fhp, read->rd_filp,
2980 			read->rd_offset, resp->rqstp->rq_vec, read->rd_vlen,
2981 			&maxcount);
2982 
2983 	if (nfserr)
2984 		return nfserr;
2985 	eof = (read->rd_offset + maxcount >=
2986 	       read->rd_fhp->fh_dentry->d_inode->i_size);
2987 
2988 	WRITE32(eof);
2989 	WRITE32(maxcount);
2990 	ADJUST_ARGS();
2991 	resp->xbuf->head[0].iov_len = (char*)p
2992 					- (char*)resp->xbuf->head[0].iov_base;
2993 	resp->xbuf->page_len = maxcount;
2994 
2995 	/* Use rest of head for padding and remaining ops: */
2996 	resp->xbuf->tail[0].iov_base = p;
2997 	resp->xbuf->tail[0].iov_len = 0;
2998 	if (maxcount&3) {
2999 		RESERVE_SPACE(4);
3000 		WRITE32(0);
3001 		resp->xbuf->tail[0].iov_base += maxcount&3;
3002 		resp->xbuf->tail[0].iov_len = 4 - (maxcount&3);
3003 		ADJUST_ARGS();
3004 	}
3005 	return 0;
3006 }
3007 
3008 static __be32
3009 nfsd4_encode_readlink(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readlink *readlink)
3010 {
3011 	int maxcount;
3012 	char *page;
3013 	__be32 *p;
3014 
3015 	if (nfserr)
3016 		return nfserr;
3017 	if (resp->xbuf->page_len)
3018 		return nfserr_resource;
3019 	if (!*resp->rqstp->rq_next_page)
3020 		return nfserr_resource;
3021 
3022 	page = page_address(*(resp->rqstp->rq_next_page++));
3023 
3024 	maxcount = PAGE_SIZE;
3025 	RESERVE_SPACE(4);
3026 
3027 	/*
3028 	 * XXX: By default, the ->readlink() VFS op will truncate symlinks
3029 	 * if they would overflow the buffer.  Is this kosher in NFSv4?  If
3030 	 * not, one easy fix is: if ->readlink() precisely fills the buffer,
3031 	 * assume that truncation occurred, and return NFS4ERR_RESOURCE.
3032 	 */
3033 	nfserr = nfsd_readlink(readlink->rl_rqstp, readlink->rl_fhp, page, &maxcount);
3034 	if (nfserr == nfserr_isdir)
3035 		return nfserr_inval;
3036 	if (nfserr)
3037 		return nfserr;
3038 
3039 	WRITE32(maxcount);
3040 	ADJUST_ARGS();
3041 	resp->xbuf->head[0].iov_len = (char*)p
3042 				- (char*)resp->xbuf->head[0].iov_base;
3043 	resp->xbuf->page_len = maxcount;
3044 
3045 	/* Use rest of head for padding and remaining ops: */
3046 	resp->xbuf->tail[0].iov_base = p;
3047 	resp->xbuf->tail[0].iov_len = 0;
3048 	if (maxcount&3) {
3049 		RESERVE_SPACE(4);
3050 		WRITE32(0);
3051 		resp->xbuf->tail[0].iov_base += maxcount&3;
3052 		resp->xbuf->tail[0].iov_len = 4 - (maxcount&3);
3053 		ADJUST_ARGS();
3054 	}
3055 	return 0;
3056 }
3057 
3058 static __be32
3059 nfsd4_encode_readdir(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_readdir *readdir)
3060 {
3061 	int maxcount;
3062 	loff_t offset;
3063 	__be32 *page, *savep, *tailbase;
3064 	__be32 *p;
3065 
3066 	if (nfserr)
3067 		return nfserr;
3068 	if (resp->xbuf->page_len)
3069 		return nfserr_resource;
3070 	if (!*resp->rqstp->rq_next_page)
3071 		return nfserr_resource;
3072 
3073 	RESERVE_SPACE(NFS4_VERIFIER_SIZE);
3074 	savep = p;
3075 
3076 	/* XXX: Following NFSv3, we ignore the READDIR verifier for now. */
3077 	WRITE32(0);
3078 	WRITE32(0);
3079 	ADJUST_ARGS();
3080 	resp->xbuf->head[0].iov_len = ((char*)resp->p) - (char*)resp->xbuf->head[0].iov_base;
3081 	tailbase = p;
3082 
3083 	maxcount = PAGE_SIZE;
3084 	if (maxcount > readdir->rd_maxcount)
3085 		maxcount = readdir->rd_maxcount;
3086 
3087 	/*
3088 	 * Convert from bytes to words, account for the two words already
3089 	 * written, make sure to leave two words at the end for the next
3090 	 * pointer and eof field.
3091 	 */
3092 	maxcount = (maxcount >> 2) - 4;
3093 	if (maxcount < 0) {
3094 		nfserr =  nfserr_toosmall;
3095 		goto err_no_verf;
3096 	}
3097 
3098 	page = page_address(*(resp->rqstp->rq_next_page++));
3099 	readdir->common.err = 0;
3100 	readdir->buflen = maxcount;
3101 	readdir->buffer = page;
3102 	readdir->offset = NULL;
3103 
3104 	offset = readdir->rd_cookie;
3105 	nfserr = nfsd_readdir(readdir->rd_rqstp, readdir->rd_fhp,
3106 			      &offset,
3107 			      &readdir->common, nfsd4_encode_dirent);
3108 	if (nfserr == nfs_ok &&
3109 	    readdir->common.err == nfserr_toosmall &&
3110 	    readdir->buffer == page)
3111 		nfserr = nfserr_toosmall;
3112 	if (nfserr)
3113 		goto err_no_verf;
3114 
3115 	if (readdir->offset)
3116 		xdr_encode_hyper(readdir->offset, offset);
3117 
3118 	p = readdir->buffer;
3119 	*p++ = 0;	/* no more entries */
3120 	*p++ = htonl(readdir->common.err == nfserr_eof);
3121 	resp->xbuf->page_len = ((char*)p) -
3122 		(char*)page_address(*(resp->rqstp->rq_next_page-1));
3123 
3124 	/* Use rest of head for padding and remaining ops: */
3125 	resp->xbuf->tail[0].iov_base = tailbase;
3126 	resp->xbuf->tail[0].iov_len = 0;
3127 	resp->p = resp->xbuf->tail[0].iov_base;
3128 	resp->end = resp->p + (PAGE_SIZE - resp->xbuf->head[0].iov_len)/4;
3129 
3130 	return 0;
3131 err_no_verf:
3132 	p = savep;
3133 	ADJUST_ARGS();
3134 	return nfserr;
3135 }
3136 
3137 static __be32
3138 nfsd4_encode_remove(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_remove *remove)
3139 {
3140 	__be32 *p;
3141 
3142 	if (!nfserr) {
3143 		RESERVE_SPACE(20);
3144 		write_cinfo(&p, &remove->rm_cinfo);
3145 		ADJUST_ARGS();
3146 	}
3147 	return nfserr;
3148 }
3149 
3150 static __be32
3151 nfsd4_encode_rename(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_rename *rename)
3152 {
3153 	__be32 *p;
3154 
3155 	if (!nfserr) {
3156 		RESERVE_SPACE(40);
3157 		write_cinfo(&p, &rename->rn_sinfo);
3158 		write_cinfo(&p, &rename->rn_tinfo);
3159 		ADJUST_ARGS();
3160 	}
3161 	return nfserr;
3162 }
3163 
3164 static __be32
3165 nfsd4_do_encode_secinfo(struct nfsd4_compoundres *resp,
3166 			 __be32 nfserr, struct svc_export *exp)
3167 {
3168 	u32 i, nflavs, supported;
3169 	struct exp_flavor_info *flavs;
3170 	struct exp_flavor_info def_flavs[2];
3171 	__be32 *p, *flavorsp;
3172 	static bool report = true;
3173 
3174 	if (nfserr)
3175 		goto out;
3176 	if (exp->ex_nflavors) {
3177 		flavs = exp->ex_flavors;
3178 		nflavs = exp->ex_nflavors;
3179 	} else { /* Handling of some defaults in absence of real secinfo: */
3180 		flavs = def_flavs;
3181 		if (exp->ex_client->flavour->flavour == RPC_AUTH_UNIX) {
3182 			nflavs = 2;
3183 			flavs[0].pseudoflavor = RPC_AUTH_UNIX;
3184 			flavs[1].pseudoflavor = RPC_AUTH_NULL;
3185 		} else if (exp->ex_client->flavour->flavour == RPC_AUTH_GSS) {
3186 			nflavs = 1;
3187 			flavs[0].pseudoflavor
3188 					= svcauth_gss_flavor(exp->ex_client);
3189 		} else {
3190 			nflavs = 1;
3191 			flavs[0].pseudoflavor
3192 					= exp->ex_client->flavour->flavour;
3193 		}
3194 	}
3195 
3196 	supported = 0;
3197 	RESERVE_SPACE(4);
3198 	flavorsp = p++;		/* to be backfilled later */
3199 	ADJUST_ARGS();
3200 
3201 	for (i = 0; i < nflavs; i++) {
3202 		rpc_authflavor_t pf = flavs[i].pseudoflavor;
3203 		struct rpcsec_gss_info info;
3204 
3205 		if (rpcauth_get_gssinfo(pf, &info) == 0) {
3206 			supported++;
3207 			RESERVE_SPACE(4 + 4 + XDR_LEN(info.oid.len) + 4 + 4);
3208 			WRITE32(RPC_AUTH_GSS);
3209 			WRITE32(info.oid.len);
3210 			WRITEMEM(info.oid.data, info.oid.len);
3211 			WRITE32(info.qop);
3212 			WRITE32(info.service);
3213 			ADJUST_ARGS();
3214 		} else if (pf < RPC_AUTH_MAXFLAVOR) {
3215 			supported++;
3216 			RESERVE_SPACE(4);
3217 			WRITE32(pf);
3218 			ADJUST_ARGS();
3219 		} else {
3220 			if (report)
3221 				pr_warn("NFS: SECINFO: security flavor %u "
3222 					"is not supported\n", pf);
3223 		}
3224 	}
3225 
3226 	if (nflavs != supported)
3227 		report = false;
3228 	*flavorsp = htonl(supported);
3229 
3230 out:
3231 	if (exp)
3232 		exp_put(exp);
3233 	return nfserr;
3234 }
3235 
3236 static __be32
3237 nfsd4_encode_secinfo(struct nfsd4_compoundres *resp, __be32 nfserr,
3238 		     struct nfsd4_secinfo *secinfo)
3239 {
3240 	return nfsd4_do_encode_secinfo(resp, nfserr, secinfo->si_exp);
3241 }
3242 
3243 static __be32
3244 nfsd4_encode_secinfo_no_name(struct nfsd4_compoundres *resp, __be32 nfserr,
3245 		     struct nfsd4_secinfo_no_name *secinfo)
3246 {
3247 	return nfsd4_do_encode_secinfo(resp, nfserr, secinfo->sin_exp);
3248 }
3249 
3250 /*
3251  * The SETATTR encode routine is special -- it always encodes a bitmap,
3252  * regardless of the error status.
3253  */
3254 static __be32
3255 nfsd4_encode_setattr(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setattr *setattr)
3256 {
3257 	__be32 *p;
3258 
3259 	RESERVE_SPACE(16);
3260 	if (nfserr) {
3261 		WRITE32(3);
3262 		WRITE32(0);
3263 		WRITE32(0);
3264 		WRITE32(0);
3265 	}
3266 	else {
3267 		WRITE32(3);
3268 		WRITE32(setattr->sa_bmval[0]);
3269 		WRITE32(setattr->sa_bmval[1]);
3270 		WRITE32(setattr->sa_bmval[2]);
3271 	}
3272 	ADJUST_ARGS();
3273 	return nfserr;
3274 }
3275 
3276 static __be32
3277 nfsd4_encode_setclientid(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_setclientid *scd)
3278 {
3279 	__be32 *p;
3280 
3281 	if (!nfserr) {
3282 		RESERVE_SPACE(8 + NFS4_VERIFIER_SIZE);
3283 		WRITEMEM(&scd->se_clientid, 8);
3284 		WRITEMEM(&scd->se_confirm, NFS4_VERIFIER_SIZE);
3285 		ADJUST_ARGS();
3286 	}
3287 	else if (nfserr == nfserr_clid_inuse) {
3288 		RESERVE_SPACE(8);
3289 		WRITE32(0);
3290 		WRITE32(0);
3291 		ADJUST_ARGS();
3292 	}
3293 	return nfserr;
3294 }
3295 
3296 static __be32
3297 nfsd4_encode_write(struct nfsd4_compoundres *resp, __be32 nfserr, struct nfsd4_write *write)
3298 {
3299 	__be32 *p;
3300 
3301 	if (!nfserr) {
3302 		RESERVE_SPACE(16);
3303 		WRITE32(write->wr_bytes_written);
3304 		WRITE32(write->wr_how_written);
3305 		WRITEMEM(write->wr_verifier.data, NFS4_VERIFIER_SIZE);
3306 		ADJUST_ARGS();
3307 	}
3308 	return nfserr;
3309 }
3310 
3311 static const u32 nfs4_minimal_spo_must_enforce[2] = {
3312 	[1] = 1 << (OP_BIND_CONN_TO_SESSION - 32) |
3313 	      1 << (OP_EXCHANGE_ID - 32) |
3314 	      1 << (OP_CREATE_SESSION - 32) |
3315 	      1 << (OP_DESTROY_SESSION - 32) |
3316 	      1 << (OP_DESTROY_CLIENTID - 32)
3317 };
3318 
3319 static __be32
3320 nfsd4_encode_exchange_id(struct nfsd4_compoundres *resp, __be32 nfserr,
3321 			 struct nfsd4_exchange_id *exid)
3322 {
3323 	__be32 *p;
3324 	char *major_id;
3325 	char *server_scope;
3326 	int major_id_sz;
3327 	int server_scope_sz;
3328 	uint64_t minor_id = 0;
3329 
3330 	if (nfserr)
3331 		return nfserr;
3332 
3333 	major_id = utsname()->nodename;
3334 	major_id_sz = strlen(major_id);
3335 	server_scope = utsname()->nodename;
3336 	server_scope_sz = strlen(server_scope);
3337 
3338 	RESERVE_SPACE(
3339 		8 /* eir_clientid */ +
3340 		4 /* eir_sequenceid */ +
3341 		4 /* eir_flags */ +
3342 		4 /* spr_how */);
3343 
3344 	WRITEMEM(&exid->clientid, 8);
3345 	WRITE32(exid->seqid);
3346 	WRITE32(exid->flags);
3347 
3348 	WRITE32(exid->spa_how);
3349 	ADJUST_ARGS();
3350 
3351 	switch (exid->spa_how) {
3352 	case SP4_NONE:
3353 		break;
3354 	case SP4_MACH_CRED:
3355 		/* spo_must_enforce, spo_must_allow */
3356 		RESERVE_SPACE(16);
3357 
3358 		/* spo_must_enforce bitmap: */
3359 		WRITE32(2);
3360 		WRITE32(nfs4_minimal_spo_must_enforce[0]);
3361 		WRITE32(nfs4_minimal_spo_must_enforce[1]);
3362 		/* empty spo_must_allow bitmap: */
3363 		WRITE32(0);
3364 
3365 		ADJUST_ARGS();
3366 		break;
3367 	default:
3368 		WARN_ON_ONCE(1);
3369 	}
3370 
3371 	RESERVE_SPACE(
3372 		8 /* so_minor_id */ +
3373 		4 /* so_major_id.len */ +
3374 		(XDR_QUADLEN(major_id_sz) * 4) +
3375 		4 /* eir_server_scope.len */ +
3376 		(XDR_QUADLEN(server_scope_sz) * 4) +
3377 		4 /* eir_server_impl_id.count (0) */);
3378 
3379 	/* The server_owner struct */
3380 	WRITE64(minor_id);      /* Minor id */
3381 	/* major id */
3382 	WRITE32(major_id_sz);
3383 	WRITEMEM(major_id, major_id_sz);
3384 
3385 	/* Server scope */
3386 	WRITE32(server_scope_sz);
3387 	WRITEMEM(server_scope, server_scope_sz);
3388 
3389 	/* Implementation id */
3390 	WRITE32(0);	/* zero length nfs_impl_id4 array */
3391 	ADJUST_ARGS();
3392 	return 0;
3393 }
3394 
3395 static __be32
3396 nfsd4_encode_create_session(struct nfsd4_compoundres *resp, __be32 nfserr,
3397 			    struct nfsd4_create_session *sess)
3398 {
3399 	__be32 *p;
3400 
3401 	if (nfserr)
3402 		return nfserr;
3403 
3404 	RESERVE_SPACE(24);
3405 	WRITEMEM(sess->sessionid.data, NFS4_MAX_SESSIONID_LEN);
3406 	WRITE32(sess->seqid);
3407 	WRITE32(sess->flags);
3408 	ADJUST_ARGS();
3409 
3410 	RESERVE_SPACE(28);
3411 	WRITE32(0); /* headerpadsz */
3412 	WRITE32(sess->fore_channel.maxreq_sz);
3413 	WRITE32(sess->fore_channel.maxresp_sz);
3414 	WRITE32(sess->fore_channel.maxresp_cached);
3415 	WRITE32(sess->fore_channel.maxops);
3416 	WRITE32(sess->fore_channel.maxreqs);
3417 	WRITE32(sess->fore_channel.nr_rdma_attrs);
3418 	ADJUST_ARGS();
3419 
3420 	if (sess->fore_channel.nr_rdma_attrs) {
3421 		RESERVE_SPACE(4);
3422 		WRITE32(sess->fore_channel.rdma_attrs);
3423 		ADJUST_ARGS();
3424 	}
3425 
3426 	RESERVE_SPACE(28);
3427 	WRITE32(0); /* headerpadsz */
3428 	WRITE32(sess->back_channel.maxreq_sz);
3429 	WRITE32(sess->back_channel.maxresp_sz);
3430 	WRITE32(sess->back_channel.maxresp_cached);
3431 	WRITE32(sess->back_channel.maxops);
3432 	WRITE32(sess->back_channel.maxreqs);
3433 	WRITE32(sess->back_channel.nr_rdma_attrs);
3434 	ADJUST_ARGS();
3435 
3436 	if (sess->back_channel.nr_rdma_attrs) {
3437 		RESERVE_SPACE(4);
3438 		WRITE32(sess->back_channel.rdma_attrs);
3439 		ADJUST_ARGS();
3440 	}
3441 	return 0;
3442 }
3443 
3444 static __be32
3445 nfsd4_encode_sequence(struct nfsd4_compoundres *resp, __be32 nfserr,
3446 		      struct nfsd4_sequence *seq)
3447 {
3448 	__be32 *p;
3449 
3450 	if (nfserr)
3451 		return nfserr;
3452 
3453 	RESERVE_SPACE(NFS4_MAX_SESSIONID_LEN + 20);
3454 	WRITEMEM(seq->sessionid.data, NFS4_MAX_SESSIONID_LEN);
3455 	WRITE32(seq->seqid);
3456 	WRITE32(seq->slotid);
3457 	/* Note slotid's are numbered from zero: */
3458 	WRITE32(seq->maxslots - 1); /* sr_highest_slotid */
3459 	WRITE32(seq->maxslots - 1); /* sr_target_highest_slotid */
3460 	WRITE32(seq->status_flags);
3461 
3462 	ADJUST_ARGS();
3463 	resp->cstate.datap = p; /* DRC cache data pointer */
3464 	return 0;
3465 }
3466 
3467 static __be32
3468 nfsd4_encode_test_stateid(struct nfsd4_compoundres *resp, __be32 nfserr,
3469 			  struct nfsd4_test_stateid *test_stateid)
3470 {
3471 	struct nfsd4_test_stateid_id *stateid, *next;
3472 	__be32 *p;
3473 
3474 	RESERVE_SPACE(4 + (4 * test_stateid->ts_num_ids));
3475 	*p++ = htonl(test_stateid->ts_num_ids);
3476 
3477 	list_for_each_entry_safe(stateid, next, &test_stateid->ts_stateid_list, ts_id_list) {
3478 		*p++ = stateid->ts_id_status;
3479 	}
3480 
3481 	ADJUST_ARGS();
3482 	return nfserr;
3483 }
3484 
3485 static __be32
3486 nfsd4_encode_noop(struct nfsd4_compoundres *resp, __be32 nfserr, void *p)
3487 {
3488 	return nfserr;
3489 }
3490 
3491 typedef __be32(* nfsd4_enc)(struct nfsd4_compoundres *, __be32, void *);
3492 
3493 /*
3494  * Note: nfsd4_enc_ops vector is shared for v4.0 and v4.1
3495  * since we don't need to filter out obsolete ops as this is
3496  * done in the decoding phase.
3497  */
3498 static nfsd4_enc nfsd4_enc_ops[] = {
3499 	[OP_ACCESS]		= (nfsd4_enc)nfsd4_encode_access,
3500 	[OP_CLOSE]		= (nfsd4_enc)nfsd4_encode_close,
3501 	[OP_COMMIT]		= (nfsd4_enc)nfsd4_encode_commit,
3502 	[OP_CREATE]		= (nfsd4_enc)nfsd4_encode_create,
3503 	[OP_DELEGPURGE]		= (nfsd4_enc)nfsd4_encode_noop,
3504 	[OP_DELEGRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
3505 	[OP_GETATTR]		= (nfsd4_enc)nfsd4_encode_getattr,
3506 	[OP_GETFH]		= (nfsd4_enc)nfsd4_encode_getfh,
3507 	[OP_LINK]		= (nfsd4_enc)nfsd4_encode_link,
3508 	[OP_LOCK]		= (nfsd4_enc)nfsd4_encode_lock,
3509 	[OP_LOCKT]		= (nfsd4_enc)nfsd4_encode_lockt,
3510 	[OP_LOCKU]		= (nfsd4_enc)nfsd4_encode_locku,
3511 	[OP_LOOKUP]		= (nfsd4_enc)nfsd4_encode_noop,
3512 	[OP_LOOKUPP]		= (nfsd4_enc)nfsd4_encode_noop,
3513 	[OP_NVERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
3514 	[OP_OPEN]		= (nfsd4_enc)nfsd4_encode_open,
3515 	[OP_OPENATTR]		= (nfsd4_enc)nfsd4_encode_noop,
3516 	[OP_OPEN_CONFIRM]	= (nfsd4_enc)nfsd4_encode_open_confirm,
3517 	[OP_OPEN_DOWNGRADE]	= (nfsd4_enc)nfsd4_encode_open_downgrade,
3518 	[OP_PUTFH]		= (nfsd4_enc)nfsd4_encode_noop,
3519 	[OP_PUTPUBFH]		= (nfsd4_enc)nfsd4_encode_noop,
3520 	[OP_PUTROOTFH]		= (nfsd4_enc)nfsd4_encode_noop,
3521 	[OP_READ]		= (nfsd4_enc)nfsd4_encode_read,
3522 	[OP_READDIR]		= (nfsd4_enc)nfsd4_encode_readdir,
3523 	[OP_READLINK]		= (nfsd4_enc)nfsd4_encode_readlink,
3524 	[OP_REMOVE]		= (nfsd4_enc)nfsd4_encode_remove,
3525 	[OP_RENAME]		= (nfsd4_enc)nfsd4_encode_rename,
3526 	[OP_RENEW]		= (nfsd4_enc)nfsd4_encode_noop,
3527 	[OP_RESTOREFH]		= (nfsd4_enc)nfsd4_encode_noop,
3528 	[OP_SAVEFH]		= (nfsd4_enc)nfsd4_encode_noop,
3529 	[OP_SECINFO]		= (nfsd4_enc)nfsd4_encode_secinfo,
3530 	[OP_SETATTR]		= (nfsd4_enc)nfsd4_encode_setattr,
3531 	[OP_SETCLIENTID]	= (nfsd4_enc)nfsd4_encode_setclientid,
3532 	[OP_SETCLIENTID_CONFIRM] = (nfsd4_enc)nfsd4_encode_noop,
3533 	[OP_VERIFY]		= (nfsd4_enc)nfsd4_encode_noop,
3534 	[OP_WRITE]		= (nfsd4_enc)nfsd4_encode_write,
3535 	[OP_RELEASE_LOCKOWNER]	= (nfsd4_enc)nfsd4_encode_noop,
3536 
3537 	/* NFSv4.1 operations */
3538 	[OP_BACKCHANNEL_CTL]	= (nfsd4_enc)nfsd4_encode_noop,
3539 	[OP_BIND_CONN_TO_SESSION] = (nfsd4_enc)nfsd4_encode_bind_conn_to_session,
3540 	[OP_EXCHANGE_ID]	= (nfsd4_enc)nfsd4_encode_exchange_id,
3541 	[OP_CREATE_SESSION]	= (nfsd4_enc)nfsd4_encode_create_session,
3542 	[OP_DESTROY_SESSION]	= (nfsd4_enc)nfsd4_encode_noop,
3543 	[OP_FREE_STATEID]	= (nfsd4_enc)nfsd4_encode_noop,
3544 	[OP_GET_DIR_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
3545 	[OP_GETDEVICEINFO]	= (nfsd4_enc)nfsd4_encode_noop,
3546 	[OP_GETDEVICELIST]	= (nfsd4_enc)nfsd4_encode_noop,
3547 	[OP_LAYOUTCOMMIT]	= (nfsd4_enc)nfsd4_encode_noop,
3548 	[OP_LAYOUTGET]		= (nfsd4_enc)nfsd4_encode_noop,
3549 	[OP_LAYOUTRETURN]	= (nfsd4_enc)nfsd4_encode_noop,
3550 	[OP_SECINFO_NO_NAME]	= (nfsd4_enc)nfsd4_encode_secinfo_no_name,
3551 	[OP_SEQUENCE]		= (nfsd4_enc)nfsd4_encode_sequence,
3552 	[OP_SET_SSV]		= (nfsd4_enc)nfsd4_encode_noop,
3553 	[OP_TEST_STATEID]	= (nfsd4_enc)nfsd4_encode_test_stateid,
3554 	[OP_WANT_DELEGATION]	= (nfsd4_enc)nfsd4_encode_noop,
3555 	[OP_DESTROY_CLIENTID]	= (nfsd4_enc)nfsd4_encode_noop,
3556 	[OP_RECLAIM_COMPLETE]	= (nfsd4_enc)nfsd4_encode_noop,
3557 };
3558 
3559 /*
3560  * Calculate the total amount of memory that the compound response has taken
3561  * after encoding the current operation with pad.
3562  *
3563  * pad: if operation is non-idempotent, pad was calculate by op_rsize_bop()
3564  *      which was specified at nfsd4_operation, else pad is zero.
3565  *
3566  * Compare this length to the session se_fmaxresp_sz and se_fmaxresp_cached.
3567  *
3568  * Our se_fmaxresp_cached will always be a multiple of PAGE_SIZE, and so
3569  * will be at least a page and will therefore hold the xdr_buf head.
3570  */
3571 __be32 nfsd4_check_resp_size(struct nfsd4_compoundres *resp, u32 pad)
3572 {
3573 	struct xdr_buf *xb = &resp->rqstp->rq_res;
3574 	struct nfsd4_session *session = NULL;
3575 	struct nfsd4_slot *slot = resp->cstate.slot;
3576 	u32 length, tlen = 0;
3577 
3578 	if (!nfsd4_has_session(&resp->cstate))
3579 		return 0;
3580 
3581 	session = resp->cstate.session;
3582 	if (session == NULL)
3583 		return 0;
3584 
3585 	if (xb->page_len == 0) {
3586 		length = (char *)resp->p - (char *)xb->head[0].iov_base + pad;
3587 	} else {
3588 		if (xb->tail[0].iov_base && xb->tail[0].iov_len > 0)
3589 			tlen = (char *)resp->p - (char *)xb->tail[0].iov_base;
3590 
3591 		length = xb->head[0].iov_len + xb->page_len + tlen + pad;
3592 	}
3593 	dprintk("%s length %u, xb->page_len %u tlen %u pad %u\n", __func__,
3594 		length, xb->page_len, tlen, pad);
3595 
3596 	if (length > session->se_fchannel.maxresp_sz)
3597 		return nfserr_rep_too_big;
3598 
3599 	if ((slot->sl_flags & NFSD4_SLOT_CACHETHIS) &&
3600 	    length > session->se_fchannel.maxresp_cached)
3601 		return nfserr_rep_too_big_to_cache;
3602 
3603 	return 0;
3604 }
3605 
3606 void
3607 nfsd4_encode_operation(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
3608 {
3609 	struct nfs4_stateowner *so = resp->cstate.replay_owner;
3610 	__be32 *statp;
3611 	__be32 *p;
3612 
3613 	RESERVE_SPACE(8);
3614 	WRITE32(op->opnum);
3615 	statp = p++;	/* to be backfilled at the end */
3616 	ADJUST_ARGS();
3617 
3618 	if (op->opnum == OP_ILLEGAL)
3619 		goto status;
3620 	BUG_ON(op->opnum < 0 || op->opnum >= ARRAY_SIZE(nfsd4_enc_ops) ||
3621 	       !nfsd4_enc_ops[op->opnum]);
3622 	op->status = nfsd4_enc_ops[op->opnum](resp, op->status, &op->u);
3623 	/* nfsd4_check_drc_limit guarantees enough room for error status */
3624 	if (!op->status)
3625 		op->status = nfsd4_check_resp_size(resp, 0);
3626 	if (so) {
3627 		so->so_replay.rp_status = op->status;
3628 		so->so_replay.rp_buflen = (char *)resp->p - (char *)(statp+1);
3629 		memcpy(so->so_replay.rp_buf, statp+1, so->so_replay.rp_buflen);
3630 	}
3631 status:
3632 	/*
3633 	 * Note: We write the status directly, instead of using WRITE32(),
3634 	 * since it is already in network byte order.
3635 	 */
3636 	*statp = op->status;
3637 }
3638 
3639 /*
3640  * Encode the reply stored in the stateowner reply cache
3641  *
3642  * XDR note: do not encode rp->rp_buflen: the buffer contains the
3643  * previously sent already encoded operation.
3644  *
3645  * called with nfs4_lock_state() held
3646  */
3647 void
3648 nfsd4_encode_replay(struct nfsd4_compoundres *resp, struct nfsd4_op *op)
3649 {
3650 	__be32 *p;
3651 	struct nfs4_replay *rp = op->replay;
3652 
3653 	BUG_ON(!rp);
3654 
3655 	RESERVE_SPACE(8);
3656 	WRITE32(op->opnum);
3657 	*p++ = rp->rp_status;  /* already xdr'ed */
3658 	ADJUST_ARGS();
3659 
3660 	RESERVE_SPACE(rp->rp_buflen);
3661 	WRITEMEM(rp->rp_buf, rp->rp_buflen);
3662 	ADJUST_ARGS();
3663 }
3664 
3665 int
3666 nfs4svc_encode_voidres(struct svc_rqst *rqstp, __be32 *p, void *dummy)
3667 {
3668         return xdr_ressize_check(rqstp, p);
3669 }
3670 
3671 int nfsd4_release_compoundargs(void *rq, __be32 *p, void *resp)
3672 {
3673 	struct svc_rqst *rqstp = rq;
3674 	struct nfsd4_compoundargs *args = rqstp->rq_argp;
3675 
3676 	if (args->ops != args->iops) {
3677 		kfree(args->ops);
3678 		args->ops = args->iops;
3679 	}
3680 	kfree(args->tmpp);
3681 	args->tmpp = NULL;
3682 	while (args->to_free) {
3683 		struct tmpbuf *tb = args->to_free;
3684 		args->to_free = tb->next;
3685 		tb->release(tb->buf);
3686 		kfree(tb);
3687 	}
3688 	return 1;
3689 }
3690 
3691 int
3692 nfs4svc_decode_compoundargs(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundargs *args)
3693 {
3694 	args->p = p;
3695 	args->end = rqstp->rq_arg.head[0].iov_base + rqstp->rq_arg.head[0].iov_len;
3696 	args->pagelist = rqstp->rq_arg.pages;
3697 	args->pagelen = rqstp->rq_arg.page_len;
3698 	args->tmpp = NULL;
3699 	args->to_free = NULL;
3700 	args->ops = args->iops;
3701 	args->rqstp = rqstp;
3702 
3703 	return !nfsd4_decode_compound(args);
3704 }
3705 
3706 int
3707 nfs4svc_encode_compoundres(struct svc_rqst *rqstp, __be32 *p, struct nfsd4_compoundres *resp)
3708 {
3709 	/*
3710 	 * All that remains is to write the tag and operation count...
3711 	 */
3712 	struct nfsd4_compound_state *cs = &resp->cstate;
3713 	struct kvec *iov;
3714 	p = resp->tagp;
3715 	*p++ = htonl(resp->taglen);
3716 	memcpy(p, resp->tag, resp->taglen);
3717 	p += XDR_QUADLEN(resp->taglen);
3718 	*p++ = htonl(resp->opcnt);
3719 
3720 	if (rqstp->rq_res.page_len)
3721 		iov = &rqstp->rq_res.tail[0];
3722 	else
3723 		iov = &rqstp->rq_res.head[0];
3724 	iov->iov_len = ((char*)resp->p) - (char*)iov->iov_base;
3725 	BUG_ON(iov->iov_len > PAGE_SIZE);
3726 	if (nfsd4_has_session(cs)) {
3727 		struct nfsd_net *nn = net_generic(SVC_NET(rqstp), nfsd_net_id);
3728 		struct nfs4_client *clp = cs->session->se_client;
3729 		if (cs->status != nfserr_replay_cache) {
3730 			nfsd4_store_cache_entry(resp);
3731 			cs->slot->sl_flags &= ~NFSD4_SLOT_INUSE;
3732 		}
3733 		/* Renew the clientid on success and on replay */
3734 		spin_lock(&nn->client_lock);
3735 		nfsd4_put_session(cs->session);
3736 		spin_unlock(&nn->client_lock);
3737 		put_client_renew(clp);
3738 	}
3739 	return 1;
3740 }
3741 
3742 /*
3743  * Local variables:
3744  *  c-basic-offset: 8
3745  * End:
3746  */
3747