xref: /openbmc/linux/fs/nfs/nfs3xdr.c (revision 275876e2)
1 /*
2  * linux/fs/nfs/nfs3xdr.c
3  *
4  * XDR functions to encode/decode NFSv3 RPC arguments and results.
5  *
6  * Copyright (C) 1996, 1997 Olaf Kirch
7  */
8 
9 #include <linux/param.h>
10 #include <linux/time.h>
11 #include <linux/mm.h>
12 #include <linux/errno.h>
13 #include <linux/string.h>
14 #include <linux/in.h>
15 #include <linux/pagemap.h>
16 #include <linux/proc_fs.h>
17 #include <linux/kdev_t.h>
18 #include <linux/sunrpc/clnt.h>
19 #include <linux/nfs.h>
20 #include <linux/nfs3.h>
21 #include <linux/nfs_fs.h>
22 #include <linux/nfsacl.h>
23 #include "internal.h"
24 
25 #define NFSDBG_FACILITY		NFSDBG_XDR
26 
27 /* Mapping from NFS error code to "errno" error code. */
28 #define errno_NFSERR_IO		EIO
29 
30 /*
31  * Declare the space requirements for NFS arguments and replies as
32  * number of 32bit-words
33  */
34 #define NFS3_fhandle_sz		(1+16)
35 #define NFS3_fh_sz		(NFS3_fhandle_sz)	/* shorthand */
36 #define NFS3_sattr_sz		(15)
37 #define NFS3_filename_sz	(1+(NFS3_MAXNAMLEN>>2))
38 #define NFS3_path_sz		(1+(NFS3_MAXPATHLEN>>2))
39 #define NFS3_fattr_sz		(21)
40 #define NFS3_cookieverf_sz	(NFS3_COOKIEVERFSIZE>>2)
41 #define NFS3_wcc_attr_sz	(6)
42 #define NFS3_pre_op_attr_sz	(1+NFS3_wcc_attr_sz)
43 #define NFS3_post_op_attr_sz	(1+NFS3_fattr_sz)
44 #define NFS3_wcc_data_sz	(NFS3_pre_op_attr_sz+NFS3_post_op_attr_sz)
45 #define NFS3_diropargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
46 
47 #define NFS3_getattrargs_sz	(NFS3_fh_sz)
48 #define NFS3_setattrargs_sz	(NFS3_fh_sz+NFS3_sattr_sz+3)
49 #define NFS3_lookupargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
50 #define NFS3_accessargs_sz	(NFS3_fh_sz+1)
51 #define NFS3_readlinkargs_sz	(NFS3_fh_sz)
52 #define NFS3_readargs_sz	(NFS3_fh_sz+3)
53 #define NFS3_writeargs_sz	(NFS3_fh_sz+5)
54 #define NFS3_createargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
55 #define NFS3_mkdirargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
56 #define NFS3_symlinkargs_sz	(NFS3_diropargs_sz+1+NFS3_sattr_sz)
57 #define NFS3_mknodargs_sz	(NFS3_diropargs_sz+2+NFS3_sattr_sz)
58 #define NFS3_removeargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
59 #define NFS3_renameargs_sz	(NFS3_diropargs_sz+NFS3_diropargs_sz)
60 #define NFS3_linkargs_sz		(NFS3_fh_sz+NFS3_diropargs_sz)
61 #define NFS3_readdirargs_sz	(NFS3_fh_sz+NFS3_cookieverf_sz+3)
62 #define NFS3_readdirplusargs_sz	(NFS3_fh_sz+NFS3_cookieverf_sz+4)
63 #define NFS3_commitargs_sz	(NFS3_fh_sz+3)
64 
65 #define NFS3_getattrres_sz	(1+NFS3_fattr_sz)
66 #define NFS3_setattrres_sz	(1+NFS3_wcc_data_sz)
67 #define NFS3_removeres_sz	(NFS3_setattrres_sz)
68 #define NFS3_lookupres_sz	(1+NFS3_fh_sz+(2 * NFS3_post_op_attr_sz))
69 #define NFS3_accessres_sz	(1+NFS3_post_op_attr_sz+1)
70 #define NFS3_readlinkres_sz	(1+NFS3_post_op_attr_sz+1)
71 #define NFS3_readres_sz		(1+NFS3_post_op_attr_sz+3)
72 #define NFS3_writeres_sz	(1+NFS3_wcc_data_sz+4)
73 #define NFS3_createres_sz	(1+NFS3_fh_sz+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
74 #define NFS3_renameres_sz	(1+(2 * NFS3_wcc_data_sz))
75 #define NFS3_linkres_sz		(1+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
76 #define NFS3_readdirres_sz	(1+NFS3_post_op_attr_sz+2)
77 #define NFS3_fsstatres_sz	(1+NFS3_post_op_attr_sz+13)
78 #define NFS3_fsinfores_sz	(1+NFS3_post_op_attr_sz+12)
79 #define NFS3_pathconfres_sz	(1+NFS3_post_op_attr_sz+6)
80 #define NFS3_commitres_sz	(1+NFS3_wcc_data_sz+2)
81 
82 #define ACL3_getaclargs_sz	(NFS3_fh_sz+1)
83 #define ACL3_setaclargs_sz	(NFS3_fh_sz+1+ \
84 				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE))
85 #define ACL3_getaclres_sz	(1+NFS3_post_op_attr_sz+1+ \
86 				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE))
87 #define ACL3_setaclres_sz	(1+NFS3_post_op_attr_sz)
88 
89 static int nfs3_stat_to_errno(enum nfs_stat);
90 
91 /*
92  * Map file type to S_IFMT bits
93  */
94 static const umode_t nfs_type2fmt[] = {
95 	[NF3BAD] = 0,
96 	[NF3REG] = S_IFREG,
97 	[NF3DIR] = S_IFDIR,
98 	[NF3BLK] = S_IFBLK,
99 	[NF3CHR] = S_IFCHR,
100 	[NF3LNK] = S_IFLNK,
101 	[NF3SOCK] = S_IFSOCK,
102 	[NF3FIFO] = S_IFIFO,
103 };
104 
105 /*
106  * While encoding arguments, set up the reply buffer in advance to
107  * receive reply data directly into the page cache.
108  */
109 static void prepare_reply_buffer(struct rpc_rqst *req, struct page **pages,
110 				 unsigned int base, unsigned int len,
111 				 unsigned int bufsize)
112 {
113 	struct rpc_auth	*auth = req->rq_cred->cr_auth;
114 	unsigned int replen;
115 
116 	replen = RPC_REPHDRSIZE + auth->au_rslack + bufsize;
117 	xdr_inline_pages(&req->rq_rcv_buf, replen << 2, pages, base, len);
118 }
119 
120 /*
121  * Handle decode buffer overflows out-of-line.
122  */
123 static void print_overflow_msg(const char *func, const struct xdr_stream *xdr)
124 {
125 	dprintk("NFS: %s prematurely hit the end of our receive buffer. "
126 		"Remaining buffer length is %tu words.\n",
127 		func, xdr->end - xdr->p);
128 }
129 
130 
131 /*
132  * Encode/decode NFSv3 basic data types
133  *
134  * Basic NFSv3 data types are defined in section 2.5 of RFC 1813:
135  * "NFS Version 3 Protocol Specification".
136  *
137  * Not all basic data types have their own encoding and decoding
138  * functions.  For run-time efficiency, some data types are encoded
139  * or decoded inline.
140  */
141 
142 static void encode_uint32(struct xdr_stream *xdr, u32 value)
143 {
144 	__be32 *p = xdr_reserve_space(xdr, 4);
145 	*p = cpu_to_be32(value);
146 }
147 
148 static int decode_uint32(struct xdr_stream *xdr, u32 *value)
149 {
150 	__be32 *p;
151 
152 	p = xdr_inline_decode(xdr, 4);
153 	if (unlikely(p == NULL))
154 		goto out_overflow;
155 	*value = be32_to_cpup(p);
156 	return 0;
157 out_overflow:
158 	print_overflow_msg(__func__, xdr);
159 	return -EIO;
160 }
161 
162 static int decode_uint64(struct xdr_stream *xdr, u64 *value)
163 {
164 	__be32 *p;
165 
166 	p = xdr_inline_decode(xdr, 8);
167 	if (unlikely(p == NULL))
168 		goto out_overflow;
169 	xdr_decode_hyper(p, value);
170 	return 0;
171 out_overflow:
172 	print_overflow_msg(__func__, xdr);
173 	return -EIO;
174 }
175 
176 /*
177  * fileid3
178  *
179  *	typedef uint64 fileid3;
180  */
181 static __be32 *xdr_decode_fileid3(__be32 *p, u64 *fileid)
182 {
183 	return xdr_decode_hyper(p, fileid);
184 }
185 
186 static int decode_fileid3(struct xdr_stream *xdr, u64 *fileid)
187 {
188 	return decode_uint64(xdr, fileid);
189 }
190 
191 /*
192  * filename3
193  *
194  *	typedef string filename3<>;
195  */
196 static void encode_filename3(struct xdr_stream *xdr,
197 			     const char *name, u32 length)
198 {
199 	__be32 *p;
200 
201 	WARN_ON_ONCE(length > NFS3_MAXNAMLEN);
202 	p = xdr_reserve_space(xdr, 4 + length);
203 	xdr_encode_opaque(p, name, length);
204 }
205 
206 static int decode_inline_filename3(struct xdr_stream *xdr,
207 				   const char **name, u32 *length)
208 {
209 	__be32 *p;
210 	u32 count;
211 
212 	p = xdr_inline_decode(xdr, 4);
213 	if (unlikely(p == NULL))
214 		goto out_overflow;
215 	count = be32_to_cpup(p);
216 	if (count > NFS3_MAXNAMLEN)
217 		goto out_nametoolong;
218 	p = xdr_inline_decode(xdr, count);
219 	if (unlikely(p == NULL))
220 		goto out_overflow;
221 	*name = (const char *)p;
222 	*length = count;
223 	return 0;
224 
225 out_nametoolong:
226 	dprintk("NFS: returned filename too long: %u\n", count);
227 	return -ENAMETOOLONG;
228 out_overflow:
229 	print_overflow_msg(__func__, xdr);
230 	return -EIO;
231 }
232 
233 /*
234  * nfspath3
235  *
236  *	typedef string nfspath3<>;
237  */
238 static void encode_nfspath3(struct xdr_stream *xdr, struct page **pages,
239 			    const u32 length)
240 {
241 	encode_uint32(xdr, length);
242 	xdr_write_pages(xdr, pages, 0, length);
243 }
244 
245 static int decode_nfspath3(struct xdr_stream *xdr)
246 {
247 	u32 recvd, count;
248 	__be32 *p;
249 
250 	p = xdr_inline_decode(xdr, 4);
251 	if (unlikely(p == NULL))
252 		goto out_overflow;
253 	count = be32_to_cpup(p);
254 	if (unlikely(count >= xdr->buf->page_len || count > NFS3_MAXPATHLEN))
255 		goto out_nametoolong;
256 	recvd = xdr_read_pages(xdr, count);
257 	if (unlikely(count > recvd))
258 		goto out_cheating;
259 	xdr_terminate_string(xdr->buf, count);
260 	return 0;
261 
262 out_nametoolong:
263 	dprintk("NFS: returned pathname too long: %u\n", count);
264 	return -ENAMETOOLONG;
265 out_cheating:
266 	dprintk("NFS: server cheating in pathname result: "
267 		"count %u > recvd %u\n", count, recvd);
268 	return -EIO;
269 out_overflow:
270 	print_overflow_msg(__func__, xdr);
271 	return -EIO;
272 }
273 
274 /*
275  * cookie3
276  *
277  *	typedef uint64 cookie3
278  */
279 static __be32 *xdr_encode_cookie3(__be32 *p, u64 cookie)
280 {
281 	return xdr_encode_hyper(p, cookie);
282 }
283 
284 static int decode_cookie3(struct xdr_stream *xdr, u64 *cookie)
285 {
286 	return decode_uint64(xdr, cookie);
287 }
288 
289 /*
290  * cookieverf3
291  *
292  *	typedef opaque cookieverf3[NFS3_COOKIEVERFSIZE];
293  */
294 static __be32 *xdr_encode_cookieverf3(__be32 *p, const __be32 *verifier)
295 {
296 	memcpy(p, verifier, NFS3_COOKIEVERFSIZE);
297 	return p + XDR_QUADLEN(NFS3_COOKIEVERFSIZE);
298 }
299 
300 static int decode_cookieverf3(struct xdr_stream *xdr, __be32 *verifier)
301 {
302 	__be32 *p;
303 
304 	p = xdr_inline_decode(xdr, NFS3_COOKIEVERFSIZE);
305 	if (unlikely(p == NULL))
306 		goto out_overflow;
307 	memcpy(verifier, p, NFS3_COOKIEVERFSIZE);
308 	return 0;
309 out_overflow:
310 	print_overflow_msg(__func__, xdr);
311 	return -EIO;
312 }
313 
314 /*
315  * createverf3
316  *
317  *	typedef opaque createverf3[NFS3_CREATEVERFSIZE];
318  */
319 static void encode_createverf3(struct xdr_stream *xdr, const __be32 *verifier)
320 {
321 	__be32 *p;
322 
323 	p = xdr_reserve_space(xdr, NFS3_CREATEVERFSIZE);
324 	memcpy(p, verifier, NFS3_CREATEVERFSIZE);
325 }
326 
327 static int decode_writeverf3(struct xdr_stream *xdr, struct nfs_write_verifier *verifier)
328 {
329 	__be32 *p;
330 
331 	p = xdr_inline_decode(xdr, NFS3_WRITEVERFSIZE);
332 	if (unlikely(p == NULL))
333 		goto out_overflow;
334 	memcpy(verifier->data, p, NFS3_WRITEVERFSIZE);
335 	return 0;
336 out_overflow:
337 	print_overflow_msg(__func__, xdr);
338 	return -EIO;
339 }
340 
341 /*
342  * size3
343  *
344  *	typedef uint64 size3;
345  */
346 static __be32 *xdr_decode_size3(__be32 *p, u64 *size)
347 {
348 	return xdr_decode_hyper(p, size);
349 }
350 
351 /*
352  * nfsstat3
353  *
354  *	enum nfsstat3 {
355  *		NFS3_OK = 0,
356  *		...
357  *	}
358  */
359 #define NFS3_OK		NFS_OK
360 
361 static int decode_nfsstat3(struct xdr_stream *xdr, enum nfs_stat *status)
362 {
363 	__be32 *p;
364 
365 	p = xdr_inline_decode(xdr, 4);
366 	if (unlikely(p == NULL))
367 		goto out_overflow;
368 	*status = be32_to_cpup(p);
369 	return 0;
370 out_overflow:
371 	print_overflow_msg(__func__, xdr);
372 	return -EIO;
373 }
374 
375 /*
376  * ftype3
377  *
378  *	enum ftype3 {
379  *		NF3REG	= 1,
380  *		NF3DIR	= 2,
381  *		NF3BLK	= 3,
382  *		NF3CHR	= 4,
383  *		NF3LNK	= 5,
384  *		NF3SOCK	= 6,
385  *		NF3FIFO	= 7
386  *	};
387  */
388 static void encode_ftype3(struct xdr_stream *xdr, const u32 type)
389 {
390 	encode_uint32(xdr, type);
391 }
392 
393 static __be32 *xdr_decode_ftype3(__be32 *p, umode_t *mode)
394 {
395 	u32 type;
396 
397 	type = be32_to_cpup(p++);
398 	if (type > NF3FIFO)
399 		type = NF3NON;
400 	*mode = nfs_type2fmt[type];
401 	return p;
402 }
403 
404 /*
405  * specdata3
406  *
407  *     struct specdata3 {
408  *             uint32  specdata1;
409  *             uint32  specdata2;
410  *     };
411  */
412 static void encode_specdata3(struct xdr_stream *xdr, const dev_t rdev)
413 {
414 	__be32 *p;
415 
416 	p = xdr_reserve_space(xdr, 8);
417 	*p++ = cpu_to_be32(MAJOR(rdev));
418 	*p = cpu_to_be32(MINOR(rdev));
419 }
420 
421 static __be32 *xdr_decode_specdata3(__be32 *p, dev_t *rdev)
422 {
423 	unsigned int major, minor;
424 
425 	major = be32_to_cpup(p++);
426 	minor = be32_to_cpup(p++);
427 	*rdev = MKDEV(major, minor);
428 	if (MAJOR(*rdev) != major || MINOR(*rdev) != minor)
429 		*rdev = 0;
430 	return p;
431 }
432 
433 /*
434  * nfs_fh3
435  *
436  *	struct nfs_fh3 {
437  *		opaque       data<NFS3_FHSIZE>;
438  *	};
439  */
440 static void encode_nfs_fh3(struct xdr_stream *xdr, const struct nfs_fh *fh)
441 {
442 	__be32 *p;
443 
444 	WARN_ON_ONCE(fh->size > NFS3_FHSIZE);
445 	p = xdr_reserve_space(xdr, 4 + fh->size);
446 	xdr_encode_opaque(p, fh->data, fh->size);
447 }
448 
449 static int decode_nfs_fh3(struct xdr_stream *xdr, struct nfs_fh *fh)
450 {
451 	u32 length;
452 	__be32 *p;
453 
454 	p = xdr_inline_decode(xdr, 4);
455 	if (unlikely(p == NULL))
456 		goto out_overflow;
457 	length = be32_to_cpup(p++);
458 	if (unlikely(length > NFS3_FHSIZE))
459 		goto out_toobig;
460 	p = xdr_inline_decode(xdr, length);
461 	if (unlikely(p == NULL))
462 		goto out_overflow;
463 	fh->size = length;
464 	memcpy(fh->data, p, length);
465 	return 0;
466 out_toobig:
467 	dprintk("NFS: file handle size (%u) too big\n", length);
468 	return -E2BIG;
469 out_overflow:
470 	print_overflow_msg(__func__, xdr);
471 	return -EIO;
472 }
473 
474 static void zero_nfs_fh3(struct nfs_fh *fh)
475 {
476 	memset(fh, 0, sizeof(*fh));
477 }
478 
479 /*
480  * nfstime3
481  *
482  *	struct nfstime3 {
483  *		uint32	seconds;
484  *		uint32	nseconds;
485  *	};
486  */
487 static __be32 *xdr_encode_nfstime3(__be32 *p, const struct timespec *timep)
488 {
489 	*p++ = cpu_to_be32(timep->tv_sec);
490 	*p++ = cpu_to_be32(timep->tv_nsec);
491 	return p;
492 }
493 
494 static __be32 *xdr_decode_nfstime3(__be32 *p, struct timespec *timep)
495 {
496 	timep->tv_sec = be32_to_cpup(p++);
497 	timep->tv_nsec = be32_to_cpup(p++);
498 	return p;
499 }
500 
501 /*
502  * sattr3
503  *
504  *	enum time_how {
505  *		DONT_CHANGE		= 0,
506  *		SET_TO_SERVER_TIME	= 1,
507  *		SET_TO_CLIENT_TIME	= 2
508  *	};
509  *
510  *	union set_mode3 switch (bool set_it) {
511  *	case TRUE:
512  *		mode3	mode;
513  *	default:
514  *		void;
515  *	};
516  *
517  *	union set_uid3 switch (bool set_it) {
518  *	case TRUE:
519  *		uid3	uid;
520  *	default:
521  *		void;
522  *	};
523  *
524  *	union set_gid3 switch (bool set_it) {
525  *	case TRUE:
526  *		gid3	gid;
527  *	default:
528  *		void;
529  *	};
530  *
531  *	union set_size3 switch (bool set_it) {
532  *	case TRUE:
533  *		size3	size;
534  *	default:
535  *		void;
536  *	};
537  *
538  *	union set_atime switch (time_how set_it) {
539  *	case SET_TO_CLIENT_TIME:
540  *		nfstime3	atime;
541  *	default:
542  *		void;
543  *	};
544  *
545  *	union set_mtime switch (time_how set_it) {
546  *	case SET_TO_CLIENT_TIME:
547  *		nfstime3  mtime;
548  *	default:
549  *		void;
550  *	};
551  *
552  *	struct sattr3 {
553  *		set_mode3	mode;
554  *		set_uid3	uid;
555  *		set_gid3	gid;
556  *		set_size3	size;
557  *		set_atime	atime;
558  *		set_mtime	mtime;
559  *	};
560  */
561 static void encode_sattr3(struct xdr_stream *xdr, const struct iattr *attr)
562 {
563 	u32 nbytes;
564 	__be32 *p;
565 
566 	/*
567 	 * In order to make only a single xdr_reserve_space() call,
568 	 * pre-compute the total number of bytes to be reserved.
569 	 * Six boolean values, one for each set_foo field, are always
570 	 * present in the encoded result, so start there.
571 	 */
572 	nbytes = 6 * 4;
573 	if (attr->ia_valid & ATTR_MODE)
574 		nbytes += 4;
575 	if (attr->ia_valid & ATTR_UID)
576 		nbytes += 4;
577 	if (attr->ia_valid & ATTR_GID)
578 		nbytes += 4;
579 	if (attr->ia_valid & ATTR_SIZE)
580 		nbytes += 8;
581 	if (attr->ia_valid & ATTR_ATIME_SET)
582 		nbytes += 8;
583 	if (attr->ia_valid & ATTR_MTIME_SET)
584 		nbytes += 8;
585 	p = xdr_reserve_space(xdr, nbytes);
586 
587 	if (attr->ia_valid & ATTR_MODE) {
588 		*p++ = xdr_one;
589 		*p++ = cpu_to_be32(attr->ia_mode & S_IALLUGO);
590 	} else
591 		*p++ = xdr_zero;
592 
593 	if (attr->ia_valid & ATTR_UID) {
594 		*p++ = xdr_one;
595 		*p++ = cpu_to_be32(from_kuid(&init_user_ns, attr->ia_uid));
596 	} else
597 		*p++ = xdr_zero;
598 
599 	if (attr->ia_valid & ATTR_GID) {
600 		*p++ = xdr_one;
601 		*p++ = cpu_to_be32(from_kgid(&init_user_ns, attr->ia_gid));
602 	} else
603 		*p++ = xdr_zero;
604 
605 	if (attr->ia_valid & ATTR_SIZE) {
606 		*p++ = xdr_one;
607 		p = xdr_encode_hyper(p, (u64)attr->ia_size);
608 	} else
609 		*p++ = xdr_zero;
610 
611 	if (attr->ia_valid & ATTR_ATIME_SET) {
612 		*p++ = xdr_two;
613 		p = xdr_encode_nfstime3(p, &attr->ia_atime);
614 	} else if (attr->ia_valid & ATTR_ATIME) {
615 		*p++ = xdr_one;
616 	} else
617 		*p++ = xdr_zero;
618 
619 	if (attr->ia_valid & ATTR_MTIME_SET) {
620 		*p++ = xdr_two;
621 		xdr_encode_nfstime3(p, &attr->ia_mtime);
622 	} else if (attr->ia_valid & ATTR_MTIME) {
623 		*p = xdr_one;
624 	} else
625 		*p = xdr_zero;
626 }
627 
628 /*
629  * fattr3
630  *
631  *	struct fattr3 {
632  *		ftype3		type;
633  *		mode3		mode;
634  *		uint32		nlink;
635  *		uid3		uid;
636  *		gid3		gid;
637  *		size3		size;
638  *		size3		used;
639  *		specdata3	rdev;
640  *		uint64		fsid;
641  *		fileid3		fileid;
642  *		nfstime3	atime;
643  *		nfstime3	mtime;
644  *		nfstime3	ctime;
645  *	};
646  */
647 static int decode_fattr3(struct xdr_stream *xdr, struct nfs_fattr *fattr)
648 {
649 	umode_t fmode;
650 	__be32 *p;
651 
652 	p = xdr_inline_decode(xdr, NFS3_fattr_sz << 2);
653 	if (unlikely(p == NULL))
654 		goto out_overflow;
655 
656 	p = xdr_decode_ftype3(p, &fmode);
657 
658 	fattr->mode = (be32_to_cpup(p++) & ~S_IFMT) | fmode;
659 	fattr->nlink = be32_to_cpup(p++);
660 	fattr->uid = make_kuid(&init_user_ns, be32_to_cpup(p++));
661 	if (!uid_valid(fattr->uid))
662 		goto out_uid;
663 	fattr->gid = make_kgid(&init_user_ns, be32_to_cpup(p++));
664 	if (!gid_valid(fattr->gid))
665 		goto out_gid;
666 
667 	p = xdr_decode_size3(p, &fattr->size);
668 	p = xdr_decode_size3(p, &fattr->du.nfs3.used);
669 	p = xdr_decode_specdata3(p, &fattr->rdev);
670 
671 	p = xdr_decode_hyper(p, &fattr->fsid.major);
672 	fattr->fsid.minor = 0;
673 
674 	p = xdr_decode_fileid3(p, &fattr->fileid);
675 	p = xdr_decode_nfstime3(p, &fattr->atime);
676 	p = xdr_decode_nfstime3(p, &fattr->mtime);
677 	xdr_decode_nfstime3(p, &fattr->ctime);
678 	fattr->change_attr = nfs_timespec_to_change_attr(&fattr->ctime);
679 
680 	fattr->valid |= NFS_ATTR_FATTR_V3;
681 	return 0;
682 out_uid:
683 	dprintk("NFS: returned invalid uid\n");
684 	return -EINVAL;
685 out_gid:
686 	dprintk("NFS: returned invalid gid\n");
687 	return -EINVAL;
688 out_overflow:
689 	print_overflow_msg(__func__, xdr);
690 	return -EIO;
691 }
692 
693 /*
694  * post_op_attr
695  *
696  *	union post_op_attr switch (bool attributes_follow) {
697  *	case TRUE:
698  *		fattr3	attributes;
699  *	case FALSE:
700  *		void;
701  *	};
702  */
703 static int decode_post_op_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
704 {
705 	__be32 *p;
706 
707 	p = xdr_inline_decode(xdr, 4);
708 	if (unlikely(p == NULL))
709 		goto out_overflow;
710 	if (*p != xdr_zero)
711 		return decode_fattr3(xdr, fattr);
712 	return 0;
713 out_overflow:
714 	print_overflow_msg(__func__, xdr);
715 	return -EIO;
716 }
717 
718 /*
719  * wcc_attr
720  *	struct wcc_attr {
721  *		size3		size;
722  *		nfstime3	mtime;
723  *		nfstime3	ctime;
724  *	};
725  */
726 static int decode_wcc_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
727 {
728 	__be32 *p;
729 
730 	p = xdr_inline_decode(xdr, NFS3_wcc_attr_sz << 2);
731 	if (unlikely(p == NULL))
732 		goto out_overflow;
733 
734 	fattr->valid |= NFS_ATTR_FATTR_PRESIZE
735 		| NFS_ATTR_FATTR_PRECHANGE
736 		| NFS_ATTR_FATTR_PREMTIME
737 		| NFS_ATTR_FATTR_PRECTIME;
738 
739 	p = xdr_decode_size3(p, &fattr->pre_size);
740 	p = xdr_decode_nfstime3(p, &fattr->pre_mtime);
741 	xdr_decode_nfstime3(p, &fattr->pre_ctime);
742 	fattr->pre_change_attr = nfs_timespec_to_change_attr(&fattr->pre_ctime);
743 
744 	return 0;
745 out_overflow:
746 	print_overflow_msg(__func__, xdr);
747 	return -EIO;
748 }
749 
750 /*
751  * pre_op_attr
752  *	union pre_op_attr switch (bool attributes_follow) {
753  *	case TRUE:
754  *		wcc_attr	attributes;
755  *	case FALSE:
756  *		void;
757  *	};
758  *
759  * wcc_data
760  *
761  *	struct wcc_data {
762  *		pre_op_attr	before;
763  *		post_op_attr	after;
764  *	};
765  */
766 static int decode_pre_op_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
767 {
768 	__be32 *p;
769 
770 	p = xdr_inline_decode(xdr, 4);
771 	if (unlikely(p == NULL))
772 		goto out_overflow;
773 	if (*p != xdr_zero)
774 		return decode_wcc_attr(xdr, fattr);
775 	return 0;
776 out_overflow:
777 	print_overflow_msg(__func__, xdr);
778 	return -EIO;
779 }
780 
781 static int decode_wcc_data(struct xdr_stream *xdr, struct nfs_fattr *fattr)
782 {
783 	int error;
784 
785 	error = decode_pre_op_attr(xdr, fattr);
786 	if (unlikely(error))
787 		goto out;
788 	error = decode_post_op_attr(xdr, fattr);
789 out:
790 	return error;
791 }
792 
793 /*
794  * post_op_fh3
795  *
796  *	union post_op_fh3 switch (bool handle_follows) {
797  *	case TRUE:
798  *		nfs_fh3  handle;
799  *	case FALSE:
800  *		void;
801  *	};
802  */
803 static int decode_post_op_fh3(struct xdr_stream *xdr, struct nfs_fh *fh)
804 {
805 	__be32 *p = xdr_inline_decode(xdr, 4);
806 	if (unlikely(p == NULL))
807 		goto out_overflow;
808 	if (*p != xdr_zero)
809 		return decode_nfs_fh3(xdr, fh);
810 	zero_nfs_fh3(fh);
811 	return 0;
812 out_overflow:
813 	print_overflow_msg(__func__, xdr);
814 	return -EIO;
815 }
816 
817 /*
818  * diropargs3
819  *
820  *	struct diropargs3 {
821  *		nfs_fh3		dir;
822  *		filename3	name;
823  *	};
824  */
825 static void encode_diropargs3(struct xdr_stream *xdr, const struct nfs_fh *fh,
826 			      const char *name, u32 length)
827 {
828 	encode_nfs_fh3(xdr, fh);
829 	encode_filename3(xdr, name, length);
830 }
831 
832 
833 /*
834  * NFSv3 XDR encode functions
835  *
836  * NFSv3 argument types are defined in section 3.3 of RFC 1813:
837  * "NFS Version 3 Protocol Specification".
838  */
839 
840 /*
841  * 3.3.1  GETATTR3args
842  *
843  *	struct GETATTR3args {
844  *		nfs_fh3  object;
845  *	};
846  */
847 static void nfs3_xdr_enc_getattr3args(struct rpc_rqst *req,
848 				      struct xdr_stream *xdr,
849 				      const struct nfs_fh *fh)
850 {
851 	encode_nfs_fh3(xdr, fh);
852 }
853 
854 /*
855  * 3.3.2  SETATTR3args
856  *
857  *	union sattrguard3 switch (bool check) {
858  *	case TRUE:
859  *		nfstime3  obj_ctime;
860  *	case FALSE:
861  *		void;
862  *	};
863  *
864  *	struct SETATTR3args {
865  *		nfs_fh3		object;
866  *		sattr3		new_attributes;
867  *		sattrguard3	guard;
868  *	};
869  */
870 static void encode_sattrguard3(struct xdr_stream *xdr,
871 			       const struct nfs3_sattrargs *args)
872 {
873 	__be32 *p;
874 
875 	if (args->guard) {
876 		p = xdr_reserve_space(xdr, 4 + 8);
877 		*p++ = xdr_one;
878 		xdr_encode_nfstime3(p, &args->guardtime);
879 	} else {
880 		p = xdr_reserve_space(xdr, 4);
881 		*p = xdr_zero;
882 	}
883 }
884 
885 static void nfs3_xdr_enc_setattr3args(struct rpc_rqst *req,
886 				      struct xdr_stream *xdr,
887 				      const struct nfs3_sattrargs *args)
888 {
889 	encode_nfs_fh3(xdr, args->fh);
890 	encode_sattr3(xdr, args->sattr);
891 	encode_sattrguard3(xdr, args);
892 }
893 
894 /*
895  * 3.3.3  LOOKUP3args
896  *
897  *	struct LOOKUP3args {
898  *		diropargs3  what;
899  *	};
900  */
901 static void nfs3_xdr_enc_lookup3args(struct rpc_rqst *req,
902 				     struct xdr_stream *xdr,
903 				     const struct nfs3_diropargs *args)
904 {
905 	encode_diropargs3(xdr, args->fh, args->name, args->len);
906 }
907 
908 /*
909  * 3.3.4  ACCESS3args
910  *
911  *	struct ACCESS3args {
912  *		nfs_fh3		object;
913  *		uint32		access;
914  *	};
915  */
916 static void encode_access3args(struct xdr_stream *xdr,
917 			       const struct nfs3_accessargs *args)
918 {
919 	encode_nfs_fh3(xdr, args->fh);
920 	encode_uint32(xdr, args->access);
921 }
922 
923 static void nfs3_xdr_enc_access3args(struct rpc_rqst *req,
924 				     struct xdr_stream *xdr,
925 				     const struct nfs3_accessargs *args)
926 {
927 	encode_access3args(xdr, args);
928 }
929 
930 /*
931  * 3.3.5  READLINK3args
932  *
933  *	struct READLINK3args {
934  *		nfs_fh3	symlink;
935  *	};
936  */
937 static void nfs3_xdr_enc_readlink3args(struct rpc_rqst *req,
938 				       struct xdr_stream *xdr,
939 				       const struct nfs3_readlinkargs *args)
940 {
941 	encode_nfs_fh3(xdr, args->fh);
942 	prepare_reply_buffer(req, args->pages, args->pgbase,
943 					args->pglen, NFS3_readlinkres_sz);
944 }
945 
946 /*
947  * 3.3.6  READ3args
948  *
949  *	struct READ3args {
950  *		nfs_fh3		file;
951  *		offset3		offset;
952  *		count3		count;
953  *	};
954  */
955 static void encode_read3args(struct xdr_stream *xdr,
956 			     const struct nfs_pgio_args *args)
957 {
958 	__be32 *p;
959 
960 	encode_nfs_fh3(xdr, args->fh);
961 
962 	p = xdr_reserve_space(xdr, 8 + 4);
963 	p = xdr_encode_hyper(p, args->offset);
964 	*p = cpu_to_be32(args->count);
965 }
966 
967 static void nfs3_xdr_enc_read3args(struct rpc_rqst *req,
968 				   struct xdr_stream *xdr,
969 				   const struct nfs_pgio_args *args)
970 {
971 	encode_read3args(xdr, args);
972 	prepare_reply_buffer(req, args->pages, args->pgbase,
973 					args->count, NFS3_readres_sz);
974 	req->rq_rcv_buf.flags |= XDRBUF_READ;
975 }
976 
977 /*
978  * 3.3.7  WRITE3args
979  *
980  *	enum stable_how {
981  *		UNSTABLE  = 0,
982  *		DATA_SYNC = 1,
983  *		FILE_SYNC = 2
984  *	};
985  *
986  *	struct WRITE3args {
987  *		nfs_fh3		file;
988  *		offset3		offset;
989  *		count3		count;
990  *		stable_how	stable;
991  *		opaque		data<>;
992  *	};
993  */
994 static void encode_write3args(struct xdr_stream *xdr,
995 			      const struct nfs_pgio_args *args)
996 {
997 	__be32 *p;
998 
999 	encode_nfs_fh3(xdr, args->fh);
1000 
1001 	p = xdr_reserve_space(xdr, 8 + 4 + 4 + 4);
1002 	p = xdr_encode_hyper(p, args->offset);
1003 	*p++ = cpu_to_be32(args->count);
1004 	*p++ = cpu_to_be32(args->stable);
1005 	*p = cpu_to_be32(args->count);
1006 	xdr_write_pages(xdr, args->pages, args->pgbase, args->count);
1007 }
1008 
1009 static void nfs3_xdr_enc_write3args(struct rpc_rqst *req,
1010 				    struct xdr_stream *xdr,
1011 				    const struct nfs_pgio_args *args)
1012 {
1013 	encode_write3args(xdr, args);
1014 	xdr->buf->flags |= XDRBUF_WRITE;
1015 }
1016 
1017 /*
1018  * 3.3.8  CREATE3args
1019  *
1020  *	enum createmode3 {
1021  *		UNCHECKED = 0,
1022  *		GUARDED   = 1,
1023  *		EXCLUSIVE = 2
1024  *	};
1025  *
1026  *	union createhow3 switch (createmode3 mode) {
1027  *	case UNCHECKED:
1028  *	case GUARDED:
1029  *		sattr3       obj_attributes;
1030  *	case EXCLUSIVE:
1031  *		createverf3  verf;
1032  *	};
1033  *
1034  *	struct CREATE3args {
1035  *		diropargs3	where;
1036  *		createhow3	how;
1037  *	};
1038  */
1039 static void encode_createhow3(struct xdr_stream *xdr,
1040 			      const struct nfs3_createargs *args)
1041 {
1042 	encode_uint32(xdr, args->createmode);
1043 	switch (args->createmode) {
1044 	case NFS3_CREATE_UNCHECKED:
1045 	case NFS3_CREATE_GUARDED:
1046 		encode_sattr3(xdr, args->sattr);
1047 		break;
1048 	case NFS3_CREATE_EXCLUSIVE:
1049 		encode_createverf3(xdr, args->verifier);
1050 		break;
1051 	default:
1052 		BUG();
1053 	}
1054 }
1055 
1056 static void nfs3_xdr_enc_create3args(struct rpc_rqst *req,
1057 				     struct xdr_stream *xdr,
1058 				     const struct nfs3_createargs *args)
1059 {
1060 	encode_diropargs3(xdr, args->fh, args->name, args->len);
1061 	encode_createhow3(xdr, args);
1062 }
1063 
1064 /*
1065  * 3.3.9  MKDIR3args
1066  *
1067  *	struct MKDIR3args {
1068  *		diropargs3	where;
1069  *		sattr3		attributes;
1070  *	};
1071  */
1072 static void nfs3_xdr_enc_mkdir3args(struct rpc_rqst *req,
1073 				    struct xdr_stream *xdr,
1074 				    const struct nfs3_mkdirargs *args)
1075 {
1076 	encode_diropargs3(xdr, args->fh, args->name, args->len);
1077 	encode_sattr3(xdr, args->sattr);
1078 }
1079 
1080 /*
1081  * 3.3.10  SYMLINK3args
1082  *
1083  *	struct symlinkdata3 {
1084  *		sattr3		symlink_attributes;
1085  *		nfspath3	symlink_data;
1086  *	};
1087  *
1088  *	struct SYMLINK3args {
1089  *		diropargs3	where;
1090  *		symlinkdata3	symlink;
1091  *	};
1092  */
1093 static void encode_symlinkdata3(struct xdr_stream *xdr,
1094 				const struct nfs3_symlinkargs *args)
1095 {
1096 	encode_sattr3(xdr, args->sattr);
1097 	encode_nfspath3(xdr, args->pages, args->pathlen);
1098 }
1099 
1100 static void nfs3_xdr_enc_symlink3args(struct rpc_rqst *req,
1101 				      struct xdr_stream *xdr,
1102 				      const struct nfs3_symlinkargs *args)
1103 {
1104 	encode_diropargs3(xdr, args->fromfh, args->fromname, args->fromlen);
1105 	encode_symlinkdata3(xdr, args);
1106 }
1107 
1108 /*
1109  * 3.3.11  MKNOD3args
1110  *
1111  *	struct devicedata3 {
1112  *		sattr3		dev_attributes;
1113  *		specdata3	spec;
1114  *	};
1115  *
1116  *	union mknoddata3 switch (ftype3 type) {
1117  *	case NF3CHR:
1118  *	case NF3BLK:
1119  *		devicedata3	device;
1120  *	case NF3SOCK:
1121  *	case NF3FIFO:
1122  *		sattr3		pipe_attributes;
1123  *	default:
1124  *		void;
1125  *	};
1126  *
1127  *	struct MKNOD3args {
1128  *		diropargs3	where;
1129  *		mknoddata3	what;
1130  *	};
1131  */
1132 static void encode_devicedata3(struct xdr_stream *xdr,
1133 			       const struct nfs3_mknodargs *args)
1134 {
1135 	encode_sattr3(xdr, args->sattr);
1136 	encode_specdata3(xdr, args->rdev);
1137 }
1138 
1139 static void encode_mknoddata3(struct xdr_stream *xdr,
1140 			      const struct nfs3_mknodargs *args)
1141 {
1142 	encode_ftype3(xdr, args->type);
1143 	switch (args->type) {
1144 	case NF3CHR:
1145 	case NF3BLK:
1146 		encode_devicedata3(xdr, args);
1147 		break;
1148 	case NF3SOCK:
1149 	case NF3FIFO:
1150 		encode_sattr3(xdr, args->sattr);
1151 		break;
1152 	case NF3REG:
1153 	case NF3DIR:
1154 		break;
1155 	default:
1156 		BUG();
1157 	}
1158 }
1159 
1160 static void nfs3_xdr_enc_mknod3args(struct rpc_rqst *req,
1161 				    struct xdr_stream *xdr,
1162 				    const struct nfs3_mknodargs *args)
1163 {
1164 	encode_diropargs3(xdr, args->fh, args->name, args->len);
1165 	encode_mknoddata3(xdr, args);
1166 }
1167 
1168 /*
1169  * 3.3.12  REMOVE3args
1170  *
1171  *	struct REMOVE3args {
1172  *		diropargs3  object;
1173  *	};
1174  */
1175 static void nfs3_xdr_enc_remove3args(struct rpc_rqst *req,
1176 				     struct xdr_stream *xdr,
1177 				     const struct nfs_removeargs *args)
1178 {
1179 	encode_diropargs3(xdr, args->fh, args->name.name, args->name.len);
1180 }
1181 
1182 /*
1183  * 3.3.14  RENAME3args
1184  *
1185  *	struct RENAME3args {
1186  *		diropargs3	from;
1187  *		diropargs3	to;
1188  *	};
1189  */
1190 static void nfs3_xdr_enc_rename3args(struct rpc_rqst *req,
1191 				     struct xdr_stream *xdr,
1192 				     const struct nfs_renameargs *args)
1193 {
1194 	const struct qstr *old = args->old_name;
1195 	const struct qstr *new = args->new_name;
1196 
1197 	encode_diropargs3(xdr, args->old_dir, old->name, old->len);
1198 	encode_diropargs3(xdr, args->new_dir, new->name, new->len);
1199 }
1200 
1201 /*
1202  * 3.3.15  LINK3args
1203  *
1204  *	struct LINK3args {
1205  *		nfs_fh3		file;
1206  *		diropargs3	link;
1207  *	};
1208  */
1209 static void nfs3_xdr_enc_link3args(struct rpc_rqst *req,
1210 				   struct xdr_stream *xdr,
1211 				   const struct nfs3_linkargs *args)
1212 {
1213 	encode_nfs_fh3(xdr, args->fromfh);
1214 	encode_diropargs3(xdr, args->tofh, args->toname, args->tolen);
1215 }
1216 
1217 /*
1218  * 3.3.16  READDIR3args
1219  *
1220  *	struct READDIR3args {
1221  *		nfs_fh3		dir;
1222  *		cookie3		cookie;
1223  *		cookieverf3	cookieverf;
1224  *		count3		count;
1225  *	};
1226  */
1227 static void encode_readdir3args(struct xdr_stream *xdr,
1228 				const struct nfs3_readdirargs *args)
1229 {
1230 	__be32 *p;
1231 
1232 	encode_nfs_fh3(xdr, args->fh);
1233 
1234 	p = xdr_reserve_space(xdr, 8 + NFS3_COOKIEVERFSIZE + 4);
1235 	p = xdr_encode_cookie3(p, args->cookie);
1236 	p = xdr_encode_cookieverf3(p, args->verf);
1237 	*p = cpu_to_be32(args->count);
1238 }
1239 
1240 static void nfs3_xdr_enc_readdir3args(struct rpc_rqst *req,
1241 				      struct xdr_stream *xdr,
1242 				      const struct nfs3_readdirargs *args)
1243 {
1244 	encode_readdir3args(xdr, args);
1245 	prepare_reply_buffer(req, args->pages, 0,
1246 				args->count, NFS3_readdirres_sz);
1247 }
1248 
1249 /*
1250  * 3.3.17  READDIRPLUS3args
1251  *
1252  *	struct READDIRPLUS3args {
1253  *		nfs_fh3		dir;
1254  *		cookie3		cookie;
1255  *		cookieverf3	cookieverf;
1256  *		count3		dircount;
1257  *		count3		maxcount;
1258  *	};
1259  */
1260 static void encode_readdirplus3args(struct xdr_stream *xdr,
1261 				    const struct nfs3_readdirargs *args)
1262 {
1263 	__be32 *p;
1264 
1265 	encode_nfs_fh3(xdr, args->fh);
1266 
1267 	p = xdr_reserve_space(xdr, 8 + NFS3_COOKIEVERFSIZE + 4 + 4);
1268 	p = xdr_encode_cookie3(p, args->cookie);
1269 	p = xdr_encode_cookieverf3(p, args->verf);
1270 
1271 	/*
1272 	 * readdirplus: need dircount + buffer size.
1273 	 * We just make sure we make dircount big enough
1274 	 */
1275 	*p++ = cpu_to_be32(args->count >> 3);
1276 
1277 	*p = cpu_to_be32(args->count);
1278 }
1279 
1280 static void nfs3_xdr_enc_readdirplus3args(struct rpc_rqst *req,
1281 					  struct xdr_stream *xdr,
1282 					  const struct nfs3_readdirargs *args)
1283 {
1284 	encode_readdirplus3args(xdr, args);
1285 	prepare_reply_buffer(req, args->pages, 0,
1286 				args->count, NFS3_readdirres_sz);
1287 }
1288 
1289 /*
1290  * 3.3.21  COMMIT3args
1291  *
1292  *	struct COMMIT3args {
1293  *		nfs_fh3		file;
1294  *		offset3		offset;
1295  *		count3		count;
1296  *	};
1297  */
1298 static void encode_commit3args(struct xdr_stream *xdr,
1299 			       const struct nfs_commitargs *args)
1300 {
1301 	__be32 *p;
1302 
1303 	encode_nfs_fh3(xdr, args->fh);
1304 
1305 	p = xdr_reserve_space(xdr, 8 + 4);
1306 	p = xdr_encode_hyper(p, args->offset);
1307 	*p = cpu_to_be32(args->count);
1308 }
1309 
1310 static void nfs3_xdr_enc_commit3args(struct rpc_rqst *req,
1311 				     struct xdr_stream *xdr,
1312 				     const struct nfs_commitargs *args)
1313 {
1314 	encode_commit3args(xdr, args);
1315 }
1316 
1317 #ifdef CONFIG_NFS_V3_ACL
1318 
1319 static void nfs3_xdr_enc_getacl3args(struct rpc_rqst *req,
1320 				     struct xdr_stream *xdr,
1321 				     const struct nfs3_getaclargs *args)
1322 {
1323 	encode_nfs_fh3(xdr, args->fh);
1324 	encode_uint32(xdr, args->mask);
1325 	if (args->mask & (NFS_ACL | NFS_DFACL))
1326 		prepare_reply_buffer(req, args->pages, 0,
1327 					NFSACL_MAXPAGES << PAGE_SHIFT,
1328 					ACL3_getaclres_sz);
1329 }
1330 
1331 static void nfs3_xdr_enc_setacl3args(struct rpc_rqst *req,
1332 				     struct xdr_stream *xdr,
1333 				     const struct nfs3_setaclargs *args)
1334 {
1335 	unsigned int base;
1336 	int error;
1337 
1338 	encode_nfs_fh3(xdr, NFS_FH(args->inode));
1339 	encode_uint32(xdr, args->mask);
1340 
1341 	base = req->rq_slen;
1342 	if (args->npages != 0)
1343 		xdr_write_pages(xdr, args->pages, 0, args->len);
1344 	else
1345 		xdr_reserve_space(xdr, NFS_ACL_INLINE_BUFSIZE);
1346 
1347 	error = nfsacl_encode(xdr->buf, base, args->inode,
1348 			    (args->mask & NFS_ACL) ?
1349 			    args->acl_access : NULL, 1, 0);
1350 	/* FIXME: this is just broken */
1351 	BUG_ON(error < 0);
1352 	error = nfsacl_encode(xdr->buf, base + error, args->inode,
1353 			    (args->mask & NFS_DFACL) ?
1354 			    args->acl_default : NULL, 1,
1355 			    NFS_ACL_DEFAULT);
1356 	BUG_ON(error < 0);
1357 }
1358 
1359 #endif  /* CONFIG_NFS_V3_ACL */
1360 
1361 /*
1362  * NFSv3 XDR decode functions
1363  *
1364  * NFSv3 result types are defined in section 3.3 of RFC 1813:
1365  * "NFS Version 3 Protocol Specification".
1366  */
1367 
1368 /*
1369  * 3.3.1  GETATTR3res
1370  *
1371  *	struct GETATTR3resok {
1372  *		fattr3		obj_attributes;
1373  *	};
1374  *
1375  *	union GETATTR3res switch (nfsstat3 status) {
1376  *	case NFS3_OK:
1377  *		GETATTR3resok  resok;
1378  *	default:
1379  *		void;
1380  *	};
1381  */
1382 static int nfs3_xdr_dec_getattr3res(struct rpc_rqst *req,
1383 				    struct xdr_stream *xdr,
1384 				    struct nfs_fattr *result)
1385 {
1386 	enum nfs_stat status;
1387 	int error;
1388 
1389 	error = decode_nfsstat3(xdr, &status);
1390 	if (unlikely(error))
1391 		goto out;
1392 	if (status != NFS3_OK)
1393 		goto out_default;
1394 	error = decode_fattr3(xdr, result);
1395 out:
1396 	return error;
1397 out_default:
1398 	return nfs3_stat_to_errno(status);
1399 }
1400 
1401 /*
1402  * 3.3.2  SETATTR3res
1403  *
1404  *	struct SETATTR3resok {
1405  *		wcc_data  obj_wcc;
1406  *	};
1407  *
1408  *	struct SETATTR3resfail {
1409  *		wcc_data  obj_wcc;
1410  *	};
1411  *
1412  *	union SETATTR3res switch (nfsstat3 status) {
1413  *	case NFS3_OK:
1414  *		SETATTR3resok   resok;
1415  *	default:
1416  *		SETATTR3resfail resfail;
1417  *	};
1418  */
1419 static int nfs3_xdr_dec_setattr3res(struct rpc_rqst *req,
1420 				    struct xdr_stream *xdr,
1421 				    struct nfs_fattr *result)
1422 {
1423 	enum nfs_stat status;
1424 	int error;
1425 
1426 	error = decode_nfsstat3(xdr, &status);
1427 	if (unlikely(error))
1428 		goto out;
1429 	error = decode_wcc_data(xdr, result);
1430 	if (unlikely(error))
1431 		goto out;
1432 	if (status != NFS3_OK)
1433 		goto out_status;
1434 out:
1435 	return error;
1436 out_status:
1437 	return nfs3_stat_to_errno(status);
1438 }
1439 
1440 /*
1441  * 3.3.3  LOOKUP3res
1442  *
1443  *	struct LOOKUP3resok {
1444  *		nfs_fh3		object;
1445  *		post_op_attr	obj_attributes;
1446  *		post_op_attr	dir_attributes;
1447  *	};
1448  *
1449  *	struct LOOKUP3resfail {
1450  *		post_op_attr	dir_attributes;
1451  *	};
1452  *
1453  *	union LOOKUP3res switch (nfsstat3 status) {
1454  *	case NFS3_OK:
1455  *		LOOKUP3resok	resok;
1456  *	default:
1457  *		LOOKUP3resfail	resfail;
1458  *	};
1459  */
1460 static int nfs3_xdr_dec_lookup3res(struct rpc_rqst *req,
1461 				   struct xdr_stream *xdr,
1462 				   struct nfs3_diropres *result)
1463 {
1464 	enum nfs_stat status;
1465 	int error;
1466 
1467 	error = decode_nfsstat3(xdr, &status);
1468 	if (unlikely(error))
1469 		goto out;
1470 	if (status != NFS3_OK)
1471 		goto out_default;
1472 	error = decode_nfs_fh3(xdr, result->fh);
1473 	if (unlikely(error))
1474 		goto out;
1475 	error = decode_post_op_attr(xdr, result->fattr);
1476 	if (unlikely(error))
1477 		goto out;
1478 	error = decode_post_op_attr(xdr, result->dir_attr);
1479 out:
1480 	return error;
1481 out_default:
1482 	error = decode_post_op_attr(xdr, result->dir_attr);
1483 	if (unlikely(error))
1484 		goto out;
1485 	return nfs3_stat_to_errno(status);
1486 }
1487 
1488 /*
1489  * 3.3.4  ACCESS3res
1490  *
1491  *	struct ACCESS3resok {
1492  *		post_op_attr	obj_attributes;
1493  *		uint32		access;
1494  *	};
1495  *
1496  *	struct ACCESS3resfail {
1497  *		post_op_attr	obj_attributes;
1498  *	};
1499  *
1500  *	union ACCESS3res switch (nfsstat3 status) {
1501  *	case NFS3_OK:
1502  *		ACCESS3resok	resok;
1503  *	default:
1504  *		ACCESS3resfail	resfail;
1505  *	};
1506  */
1507 static int nfs3_xdr_dec_access3res(struct rpc_rqst *req,
1508 				   struct xdr_stream *xdr,
1509 				   struct nfs3_accessres *result)
1510 {
1511 	enum nfs_stat status;
1512 	int error;
1513 
1514 	error = decode_nfsstat3(xdr, &status);
1515 	if (unlikely(error))
1516 		goto out;
1517 	error = decode_post_op_attr(xdr, result->fattr);
1518 	if (unlikely(error))
1519 		goto out;
1520 	if (status != NFS3_OK)
1521 		goto out_default;
1522 	error = decode_uint32(xdr, &result->access);
1523 out:
1524 	return error;
1525 out_default:
1526 	return nfs3_stat_to_errno(status);
1527 }
1528 
1529 /*
1530  * 3.3.5  READLINK3res
1531  *
1532  *	struct READLINK3resok {
1533  *		post_op_attr	symlink_attributes;
1534  *		nfspath3	data;
1535  *	};
1536  *
1537  *	struct READLINK3resfail {
1538  *		post_op_attr	symlink_attributes;
1539  *	};
1540  *
1541  *	union READLINK3res switch (nfsstat3 status) {
1542  *	case NFS3_OK:
1543  *		READLINK3resok	resok;
1544  *	default:
1545  *		READLINK3resfail resfail;
1546  *	};
1547  */
1548 static int nfs3_xdr_dec_readlink3res(struct rpc_rqst *req,
1549 				     struct xdr_stream *xdr,
1550 				     struct nfs_fattr *result)
1551 {
1552 	enum nfs_stat status;
1553 	int error;
1554 
1555 	error = decode_nfsstat3(xdr, &status);
1556 	if (unlikely(error))
1557 		goto out;
1558 	error = decode_post_op_attr(xdr, result);
1559 	if (unlikely(error))
1560 		goto out;
1561 	if (status != NFS3_OK)
1562 		goto out_default;
1563 	error = decode_nfspath3(xdr);
1564 out:
1565 	return error;
1566 out_default:
1567 	return nfs3_stat_to_errno(status);
1568 }
1569 
1570 /*
1571  * 3.3.6  READ3res
1572  *
1573  *	struct READ3resok {
1574  *		post_op_attr	file_attributes;
1575  *		count3		count;
1576  *		bool		eof;
1577  *		opaque		data<>;
1578  *	};
1579  *
1580  *	struct READ3resfail {
1581  *		post_op_attr	file_attributes;
1582  *	};
1583  *
1584  *	union READ3res switch (nfsstat3 status) {
1585  *	case NFS3_OK:
1586  *		READ3resok	resok;
1587  *	default:
1588  *		READ3resfail	resfail;
1589  *	};
1590  */
1591 static int decode_read3resok(struct xdr_stream *xdr,
1592 			     struct nfs_pgio_res *result)
1593 {
1594 	u32 eof, count, ocount, recvd;
1595 	__be32 *p;
1596 
1597 	p = xdr_inline_decode(xdr, 4 + 4 + 4);
1598 	if (unlikely(p == NULL))
1599 		goto out_overflow;
1600 	count = be32_to_cpup(p++);
1601 	eof = be32_to_cpup(p++);
1602 	ocount = be32_to_cpup(p++);
1603 	if (unlikely(ocount != count))
1604 		goto out_mismatch;
1605 	recvd = xdr_read_pages(xdr, count);
1606 	if (unlikely(count > recvd))
1607 		goto out_cheating;
1608 out:
1609 	result->eof = eof;
1610 	result->count = count;
1611 	return count;
1612 out_mismatch:
1613 	dprintk("NFS: READ count doesn't match length of opaque: "
1614 		"count %u != ocount %u\n", count, ocount);
1615 	return -EIO;
1616 out_cheating:
1617 	dprintk("NFS: server cheating in read result: "
1618 		"count %u > recvd %u\n", count, recvd);
1619 	count = recvd;
1620 	eof = 0;
1621 	goto out;
1622 out_overflow:
1623 	print_overflow_msg(__func__, xdr);
1624 	return -EIO;
1625 }
1626 
1627 static int nfs3_xdr_dec_read3res(struct rpc_rqst *req, struct xdr_stream *xdr,
1628 				 struct nfs_pgio_res *result)
1629 {
1630 	enum nfs_stat status;
1631 	int error;
1632 
1633 	error = decode_nfsstat3(xdr, &status);
1634 	if (unlikely(error))
1635 		goto out;
1636 	error = decode_post_op_attr(xdr, result->fattr);
1637 	if (unlikely(error))
1638 		goto out;
1639 	if (status != NFS3_OK)
1640 		goto out_status;
1641 	error = decode_read3resok(xdr, result);
1642 out:
1643 	return error;
1644 out_status:
1645 	return nfs3_stat_to_errno(status);
1646 }
1647 
1648 /*
1649  * 3.3.7  WRITE3res
1650  *
1651  *	enum stable_how {
1652  *		UNSTABLE  = 0,
1653  *		DATA_SYNC = 1,
1654  *		FILE_SYNC = 2
1655  *	};
1656  *
1657  *	struct WRITE3resok {
1658  *		wcc_data	file_wcc;
1659  *		count3		count;
1660  *		stable_how	committed;
1661  *		writeverf3	verf;
1662  *	};
1663  *
1664  *	struct WRITE3resfail {
1665  *		wcc_data	file_wcc;
1666  *	};
1667  *
1668  *	union WRITE3res switch (nfsstat3 status) {
1669  *	case NFS3_OK:
1670  *		WRITE3resok	resok;
1671  *	default:
1672  *		WRITE3resfail	resfail;
1673  *	};
1674  */
1675 static int decode_write3resok(struct xdr_stream *xdr,
1676 			      struct nfs_pgio_res *result)
1677 {
1678 	__be32 *p;
1679 
1680 	p = xdr_inline_decode(xdr, 4 + 4);
1681 	if (unlikely(p == NULL))
1682 		goto out_overflow;
1683 	result->count = be32_to_cpup(p++);
1684 	result->verf->committed = be32_to_cpup(p++);
1685 	if (unlikely(result->verf->committed > NFS_FILE_SYNC))
1686 		goto out_badvalue;
1687 	if (decode_writeverf3(xdr, &result->verf->verifier))
1688 		goto out_eio;
1689 	return result->count;
1690 out_badvalue:
1691 	dprintk("NFS: bad stable_how value: %u\n", result->verf->committed);
1692 	return -EIO;
1693 out_overflow:
1694 	print_overflow_msg(__func__, xdr);
1695 out_eio:
1696 	return -EIO;
1697 }
1698 
1699 static int nfs3_xdr_dec_write3res(struct rpc_rqst *req, struct xdr_stream *xdr,
1700 				  struct nfs_pgio_res *result)
1701 {
1702 	enum nfs_stat status;
1703 	int error;
1704 
1705 	error = decode_nfsstat3(xdr, &status);
1706 	if (unlikely(error))
1707 		goto out;
1708 	error = decode_wcc_data(xdr, result->fattr);
1709 	if (unlikely(error))
1710 		goto out;
1711 	if (status != NFS3_OK)
1712 		goto out_status;
1713 	error = decode_write3resok(xdr, result);
1714 out:
1715 	return error;
1716 out_status:
1717 	return nfs3_stat_to_errno(status);
1718 }
1719 
1720 /*
1721  * 3.3.8  CREATE3res
1722  *
1723  *	struct CREATE3resok {
1724  *		post_op_fh3	obj;
1725  *		post_op_attr	obj_attributes;
1726  *		wcc_data	dir_wcc;
1727  *	};
1728  *
1729  *	struct CREATE3resfail {
1730  *		wcc_data	dir_wcc;
1731  *	};
1732  *
1733  *	union CREATE3res switch (nfsstat3 status) {
1734  *	case NFS3_OK:
1735  *		CREATE3resok	resok;
1736  *	default:
1737  *		CREATE3resfail	resfail;
1738  *	};
1739  */
1740 static int decode_create3resok(struct xdr_stream *xdr,
1741 			       struct nfs3_diropres *result)
1742 {
1743 	int error;
1744 
1745 	error = decode_post_op_fh3(xdr, result->fh);
1746 	if (unlikely(error))
1747 		goto out;
1748 	error = decode_post_op_attr(xdr, result->fattr);
1749 	if (unlikely(error))
1750 		goto out;
1751 	/* The server isn't required to return a file handle.
1752 	 * If it didn't, force the client to perform a LOOKUP
1753 	 * to determine the correct file handle and attribute
1754 	 * values for the new object. */
1755 	if (result->fh->size == 0)
1756 		result->fattr->valid = 0;
1757 	error = decode_wcc_data(xdr, result->dir_attr);
1758 out:
1759 	return error;
1760 }
1761 
1762 static int nfs3_xdr_dec_create3res(struct rpc_rqst *req,
1763 				   struct xdr_stream *xdr,
1764 				   struct nfs3_diropres *result)
1765 {
1766 	enum nfs_stat status;
1767 	int error;
1768 
1769 	error = decode_nfsstat3(xdr, &status);
1770 	if (unlikely(error))
1771 		goto out;
1772 	if (status != NFS3_OK)
1773 		goto out_default;
1774 	error = decode_create3resok(xdr, result);
1775 out:
1776 	return error;
1777 out_default:
1778 	error = decode_wcc_data(xdr, result->dir_attr);
1779 	if (unlikely(error))
1780 		goto out;
1781 	return nfs3_stat_to_errno(status);
1782 }
1783 
1784 /*
1785  * 3.3.12  REMOVE3res
1786  *
1787  *	struct REMOVE3resok {
1788  *		wcc_data    dir_wcc;
1789  *	};
1790  *
1791  *	struct REMOVE3resfail {
1792  *		wcc_data    dir_wcc;
1793  *	};
1794  *
1795  *	union REMOVE3res switch (nfsstat3 status) {
1796  *	case NFS3_OK:
1797  *		REMOVE3resok   resok;
1798  *	default:
1799  *		REMOVE3resfail resfail;
1800  *	};
1801  */
1802 static int nfs3_xdr_dec_remove3res(struct rpc_rqst *req,
1803 				   struct xdr_stream *xdr,
1804 				   struct nfs_removeres *result)
1805 {
1806 	enum nfs_stat status;
1807 	int error;
1808 
1809 	error = decode_nfsstat3(xdr, &status);
1810 	if (unlikely(error))
1811 		goto out;
1812 	error = decode_wcc_data(xdr, result->dir_attr);
1813 	if (unlikely(error))
1814 		goto out;
1815 	if (status != NFS3_OK)
1816 		goto out_status;
1817 out:
1818 	return error;
1819 out_status:
1820 	return nfs3_stat_to_errno(status);
1821 }
1822 
1823 /*
1824  * 3.3.14  RENAME3res
1825  *
1826  *	struct RENAME3resok {
1827  *		wcc_data	fromdir_wcc;
1828  *		wcc_data	todir_wcc;
1829  *	};
1830  *
1831  *	struct RENAME3resfail {
1832  *		wcc_data	fromdir_wcc;
1833  *		wcc_data	todir_wcc;
1834  *	};
1835  *
1836  *	union RENAME3res switch (nfsstat3 status) {
1837  *	case NFS3_OK:
1838  *		RENAME3resok   resok;
1839  *	default:
1840  *		RENAME3resfail resfail;
1841  *	};
1842  */
1843 static int nfs3_xdr_dec_rename3res(struct rpc_rqst *req,
1844 				   struct xdr_stream *xdr,
1845 				   struct nfs_renameres *result)
1846 {
1847 	enum nfs_stat status;
1848 	int error;
1849 
1850 	error = decode_nfsstat3(xdr, &status);
1851 	if (unlikely(error))
1852 		goto out;
1853 	error = decode_wcc_data(xdr, result->old_fattr);
1854 	if (unlikely(error))
1855 		goto out;
1856 	error = decode_wcc_data(xdr, result->new_fattr);
1857 	if (unlikely(error))
1858 		goto out;
1859 	if (status != NFS3_OK)
1860 		goto out_status;
1861 out:
1862 	return error;
1863 out_status:
1864 	return nfs3_stat_to_errno(status);
1865 }
1866 
1867 /*
1868  * 3.3.15  LINK3res
1869  *
1870  *	struct LINK3resok {
1871  *		post_op_attr	file_attributes;
1872  *		wcc_data	linkdir_wcc;
1873  *	};
1874  *
1875  *	struct LINK3resfail {
1876  *		post_op_attr	file_attributes;
1877  *		wcc_data	linkdir_wcc;
1878  *	};
1879  *
1880  *	union LINK3res switch (nfsstat3 status) {
1881  *	case NFS3_OK:
1882  *		LINK3resok	resok;
1883  *	default:
1884  *		LINK3resfail	resfail;
1885  *	};
1886  */
1887 static int nfs3_xdr_dec_link3res(struct rpc_rqst *req, struct xdr_stream *xdr,
1888 				 struct nfs3_linkres *result)
1889 {
1890 	enum nfs_stat status;
1891 	int error;
1892 
1893 	error = decode_nfsstat3(xdr, &status);
1894 	if (unlikely(error))
1895 		goto out;
1896 	error = decode_post_op_attr(xdr, result->fattr);
1897 	if (unlikely(error))
1898 		goto out;
1899 	error = decode_wcc_data(xdr, result->dir_attr);
1900 	if (unlikely(error))
1901 		goto out;
1902 	if (status != NFS3_OK)
1903 		goto out_status;
1904 out:
1905 	return error;
1906 out_status:
1907 	return nfs3_stat_to_errno(status);
1908 }
1909 
1910 /**
1911  * nfs3_decode_dirent - Decode a single NFSv3 directory entry stored in
1912  *			the local page cache
1913  * @xdr: XDR stream where entry resides
1914  * @entry: buffer to fill in with entry data
1915  * @plus: boolean indicating whether this should be a readdirplus entry
1916  *
1917  * Returns zero if successful, otherwise a negative errno value is
1918  * returned.
1919  *
1920  * This function is not invoked during READDIR reply decoding, but
1921  * rather whenever an application invokes the getdents(2) system call
1922  * on a directory already in our cache.
1923  *
1924  * 3.3.16  entry3
1925  *
1926  *	struct entry3 {
1927  *		fileid3		fileid;
1928  *		filename3	name;
1929  *		cookie3		cookie;
1930  *		fhandle3	filehandle;
1931  *		post_op_attr3	attributes;
1932  *		entry3		*nextentry;
1933  *	};
1934  *
1935  * 3.3.17  entryplus3
1936  *	struct entryplus3 {
1937  *		fileid3		fileid;
1938  *		filename3	name;
1939  *		cookie3		cookie;
1940  *		post_op_attr	name_attributes;
1941  *		post_op_fh3	name_handle;
1942  *		entryplus3	*nextentry;
1943  *	};
1944  */
1945 int nfs3_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry,
1946 		       int plus)
1947 {
1948 	struct nfs_entry old = *entry;
1949 	__be32 *p;
1950 	int error;
1951 
1952 	p = xdr_inline_decode(xdr, 4);
1953 	if (unlikely(p == NULL))
1954 		goto out_overflow;
1955 	if (*p == xdr_zero) {
1956 		p = xdr_inline_decode(xdr, 4);
1957 		if (unlikely(p == NULL))
1958 			goto out_overflow;
1959 		if (*p == xdr_zero)
1960 			return -EAGAIN;
1961 		entry->eof = 1;
1962 		return -EBADCOOKIE;
1963 	}
1964 
1965 	error = decode_fileid3(xdr, &entry->ino);
1966 	if (unlikely(error))
1967 		return error;
1968 
1969 	error = decode_inline_filename3(xdr, &entry->name, &entry->len);
1970 	if (unlikely(error))
1971 		return error;
1972 
1973 	entry->prev_cookie = entry->cookie;
1974 	error = decode_cookie3(xdr, &entry->cookie);
1975 	if (unlikely(error))
1976 		return error;
1977 
1978 	entry->d_type = DT_UNKNOWN;
1979 
1980 	if (plus) {
1981 		entry->fattr->valid = 0;
1982 		error = decode_post_op_attr(xdr, entry->fattr);
1983 		if (unlikely(error))
1984 			return error;
1985 		if (entry->fattr->valid & NFS_ATTR_FATTR_V3)
1986 			entry->d_type = nfs_umode_to_dtype(entry->fattr->mode);
1987 
1988 		/* In fact, a post_op_fh3: */
1989 		p = xdr_inline_decode(xdr, 4);
1990 		if (unlikely(p == NULL))
1991 			goto out_overflow;
1992 		if (*p != xdr_zero) {
1993 			error = decode_nfs_fh3(xdr, entry->fh);
1994 			if (unlikely(error)) {
1995 				if (error == -E2BIG)
1996 					goto out_truncated;
1997 				return error;
1998 			}
1999 		} else
2000 			zero_nfs_fh3(entry->fh);
2001 	}
2002 
2003 	return 0;
2004 
2005 out_overflow:
2006 	print_overflow_msg(__func__, xdr);
2007 	return -EAGAIN;
2008 out_truncated:
2009 	dprintk("NFS: directory entry contains invalid file handle\n");
2010 	*entry = old;
2011 	return -EAGAIN;
2012 }
2013 
2014 /*
2015  * 3.3.16  READDIR3res
2016  *
2017  *	struct dirlist3 {
2018  *		entry3		*entries;
2019  *		bool		eof;
2020  *	};
2021  *
2022  *	struct READDIR3resok {
2023  *		post_op_attr	dir_attributes;
2024  *		cookieverf3	cookieverf;
2025  *		dirlist3	reply;
2026  *	};
2027  *
2028  *	struct READDIR3resfail {
2029  *		post_op_attr	dir_attributes;
2030  *	};
2031  *
2032  *	union READDIR3res switch (nfsstat3 status) {
2033  *	case NFS3_OK:
2034  *		READDIR3resok	resok;
2035  *	default:
2036  *		READDIR3resfail	resfail;
2037  *	};
2038  *
2039  * Read the directory contents into the page cache, but otherwise
2040  * don't touch them.  The actual decoding is done by nfs3_decode_entry()
2041  * during subsequent nfs_readdir() calls.
2042  */
2043 static int decode_dirlist3(struct xdr_stream *xdr)
2044 {
2045 	return xdr_read_pages(xdr, xdr->buf->page_len);
2046 }
2047 
2048 static int decode_readdir3resok(struct xdr_stream *xdr,
2049 				struct nfs3_readdirres *result)
2050 {
2051 	int error;
2052 
2053 	error = decode_post_op_attr(xdr, result->dir_attr);
2054 	if (unlikely(error))
2055 		goto out;
2056 	/* XXX: do we need to check if result->verf != NULL ? */
2057 	error = decode_cookieverf3(xdr, result->verf);
2058 	if (unlikely(error))
2059 		goto out;
2060 	error = decode_dirlist3(xdr);
2061 out:
2062 	return error;
2063 }
2064 
2065 static int nfs3_xdr_dec_readdir3res(struct rpc_rqst *req,
2066 				    struct xdr_stream *xdr,
2067 				    struct nfs3_readdirres *result)
2068 {
2069 	enum nfs_stat status;
2070 	int error;
2071 
2072 	error = decode_nfsstat3(xdr, &status);
2073 	if (unlikely(error))
2074 		goto out;
2075 	if (status != NFS3_OK)
2076 		goto out_default;
2077 	error = decode_readdir3resok(xdr, result);
2078 out:
2079 	return error;
2080 out_default:
2081 	error = decode_post_op_attr(xdr, result->dir_attr);
2082 	if (unlikely(error))
2083 		goto out;
2084 	return nfs3_stat_to_errno(status);
2085 }
2086 
2087 /*
2088  * 3.3.18  FSSTAT3res
2089  *
2090  *	struct FSSTAT3resok {
2091  *		post_op_attr	obj_attributes;
2092  *		size3		tbytes;
2093  *		size3		fbytes;
2094  *		size3		abytes;
2095  *		size3		tfiles;
2096  *		size3		ffiles;
2097  *		size3		afiles;
2098  *		uint32		invarsec;
2099  *	};
2100  *
2101  *	struct FSSTAT3resfail {
2102  *		post_op_attr	obj_attributes;
2103  *	};
2104  *
2105  *	union FSSTAT3res switch (nfsstat3 status) {
2106  *	case NFS3_OK:
2107  *		FSSTAT3resok	resok;
2108  *	default:
2109  *		FSSTAT3resfail	resfail;
2110  *	};
2111  */
2112 static int decode_fsstat3resok(struct xdr_stream *xdr,
2113 			       struct nfs_fsstat *result)
2114 {
2115 	__be32 *p;
2116 
2117 	p = xdr_inline_decode(xdr, 8 * 6 + 4);
2118 	if (unlikely(p == NULL))
2119 		goto out_overflow;
2120 	p = xdr_decode_size3(p, &result->tbytes);
2121 	p = xdr_decode_size3(p, &result->fbytes);
2122 	p = xdr_decode_size3(p, &result->abytes);
2123 	p = xdr_decode_size3(p, &result->tfiles);
2124 	p = xdr_decode_size3(p, &result->ffiles);
2125 	xdr_decode_size3(p, &result->afiles);
2126 	/* ignore invarsec */
2127 	return 0;
2128 out_overflow:
2129 	print_overflow_msg(__func__, xdr);
2130 	return -EIO;
2131 }
2132 
2133 static int nfs3_xdr_dec_fsstat3res(struct rpc_rqst *req,
2134 				   struct xdr_stream *xdr,
2135 				   struct nfs_fsstat *result)
2136 {
2137 	enum nfs_stat status;
2138 	int error;
2139 
2140 	error = decode_nfsstat3(xdr, &status);
2141 	if (unlikely(error))
2142 		goto out;
2143 	error = decode_post_op_attr(xdr, result->fattr);
2144 	if (unlikely(error))
2145 		goto out;
2146 	if (status != NFS3_OK)
2147 		goto out_status;
2148 	error = decode_fsstat3resok(xdr, result);
2149 out:
2150 	return error;
2151 out_status:
2152 	return nfs3_stat_to_errno(status);
2153 }
2154 
2155 /*
2156  * 3.3.19  FSINFO3res
2157  *
2158  *	struct FSINFO3resok {
2159  *		post_op_attr	obj_attributes;
2160  *		uint32		rtmax;
2161  *		uint32		rtpref;
2162  *		uint32		rtmult;
2163  *		uint32		wtmax;
2164  *		uint32		wtpref;
2165  *		uint32		wtmult;
2166  *		uint32		dtpref;
2167  *		size3		maxfilesize;
2168  *		nfstime3	time_delta;
2169  *		uint32		properties;
2170  *	};
2171  *
2172  *	struct FSINFO3resfail {
2173  *		post_op_attr	obj_attributes;
2174  *	};
2175  *
2176  *	union FSINFO3res switch (nfsstat3 status) {
2177  *	case NFS3_OK:
2178  *		FSINFO3resok	resok;
2179  *	default:
2180  *		FSINFO3resfail	resfail;
2181  *	};
2182  */
2183 static int decode_fsinfo3resok(struct xdr_stream *xdr,
2184 			       struct nfs_fsinfo *result)
2185 {
2186 	__be32 *p;
2187 
2188 	p = xdr_inline_decode(xdr, 4 * 7 + 8 + 8 + 4);
2189 	if (unlikely(p == NULL))
2190 		goto out_overflow;
2191 	result->rtmax  = be32_to_cpup(p++);
2192 	result->rtpref = be32_to_cpup(p++);
2193 	result->rtmult = be32_to_cpup(p++);
2194 	result->wtmax  = be32_to_cpup(p++);
2195 	result->wtpref = be32_to_cpup(p++);
2196 	result->wtmult = be32_to_cpup(p++);
2197 	result->dtpref = be32_to_cpup(p++);
2198 	p = xdr_decode_size3(p, &result->maxfilesize);
2199 	xdr_decode_nfstime3(p, &result->time_delta);
2200 
2201 	/* ignore properties */
2202 	result->lease_time = 0;
2203 	return 0;
2204 out_overflow:
2205 	print_overflow_msg(__func__, xdr);
2206 	return -EIO;
2207 }
2208 
2209 static int nfs3_xdr_dec_fsinfo3res(struct rpc_rqst *req,
2210 				   struct xdr_stream *xdr,
2211 				   struct nfs_fsinfo *result)
2212 {
2213 	enum nfs_stat status;
2214 	int error;
2215 
2216 	error = decode_nfsstat3(xdr, &status);
2217 	if (unlikely(error))
2218 		goto out;
2219 	error = decode_post_op_attr(xdr, result->fattr);
2220 	if (unlikely(error))
2221 		goto out;
2222 	if (status != NFS3_OK)
2223 		goto out_status;
2224 	error = decode_fsinfo3resok(xdr, result);
2225 out:
2226 	return error;
2227 out_status:
2228 	return nfs3_stat_to_errno(status);
2229 }
2230 
2231 /*
2232  * 3.3.20  PATHCONF3res
2233  *
2234  *	struct PATHCONF3resok {
2235  *		post_op_attr	obj_attributes;
2236  *		uint32		linkmax;
2237  *		uint32		name_max;
2238  *		bool		no_trunc;
2239  *		bool		chown_restricted;
2240  *		bool		case_insensitive;
2241  *		bool		case_preserving;
2242  *	};
2243  *
2244  *	struct PATHCONF3resfail {
2245  *		post_op_attr	obj_attributes;
2246  *	};
2247  *
2248  *	union PATHCONF3res switch (nfsstat3 status) {
2249  *	case NFS3_OK:
2250  *		PATHCONF3resok	resok;
2251  *	default:
2252  *		PATHCONF3resfail resfail;
2253  *	};
2254  */
2255 static int decode_pathconf3resok(struct xdr_stream *xdr,
2256 				 struct nfs_pathconf *result)
2257 {
2258 	__be32 *p;
2259 
2260 	p = xdr_inline_decode(xdr, 4 * 6);
2261 	if (unlikely(p == NULL))
2262 		goto out_overflow;
2263 	result->max_link = be32_to_cpup(p++);
2264 	result->max_namelen = be32_to_cpup(p);
2265 	/* ignore remaining fields */
2266 	return 0;
2267 out_overflow:
2268 	print_overflow_msg(__func__, xdr);
2269 	return -EIO;
2270 }
2271 
2272 static int nfs3_xdr_dec_pathconf3res(struct rpc_rqst *req,
2273 				     struct xdr_stream *xdr,
2274 				     struct nfs_pathconf *result)
2275 {
2276 	enum nfs_stat status;
2277 	int error;
2278 
2279 	error = decode_nfsstat3(xdr, &status);
2280 	if (unlikely(error))
2281 		goto out;
2282 	error = decode_post_op_attr(xdr, result->fattr);
2283 	if (unlikely(error))
2284 		goto out;
2285 	if (status != NFS3_OK)
2286 		goto out_status;
2287 	error = decode_pathconf3resok(xdr, result);
2288 out:
2289 	return error;
2290 out_status:
2291 	return nfs3_stat_to_errno(status);
2292 }
2293 
2294 /*
2295  * 3.3.21  COMMIT3res
2296  *
2297  *	struct COMMIT3resok {
2298  *		wcc_data	file_wcc;
2299  *		writeverf3	verf;
2300  *	};
2301  *
2302  *	struct COMMIT3resfail {
2303  *		wcc_data	file_wcc;
2304  *	};
2305  *
2306  *	union COMMIT3res switch (nfsstat3 status) {
2307  *	case NFS3_OK:
2308  *		COMMIT3resok	resok;
2309  *	default:
2310  *		COMMIT3resfail	resfail;
2311  *	};
2312  */
2313 static int nfs3_xdr_dec_commit3res(struct rpc_rqst *req,
2314 				   struct xdr_stream *xdr,
2315 				   struct nfs_commitres *result)
2316 {
2317 	enum nfs_stat status;
2318 	int error;
2319 
2320 	error = decode_nfsstat3(xdr, &status);
2321 	if (unlikely(error))
2322 		goto out;
2323 	error = decode_wcc_data(xdr, result->fattr);
2324 	if (unlikely(error))
2325 		goto out;
2326 	if (status != NFS3_OK)
2327 		goto out_status;
2328 	error = decode_writeverf3(xdr, &result->verf->verifier);
2329 out:
2330 	return error;
2331 out_status:
2332 	return nfs3_stat_to_errno(status);
2333 }
2334 
2335 #ifdef CONFIG_NFS_V3_ACL
2336 
2337 static inline int decode_getacl3resok(struct xdr_stream *xdr,
2338 				      struct nfs3_getaclres *result)
2339 {
2340 	struct posix_acl **acl;
2341 	unsigned int *aclcnt;
2342 	size_t hdrlen;
2343 	int error;
2344 
2345 	error = decode_post_op_attr(xdr, result->fattr);
2346 	if (unlikely(error))
2347 		goto out;
2348 	error = decode_uint32(xdr, &result->mask);
2349 	if (unlikely(error))
2350 		goto out;
2351 	error = -EINVAL;
2352 	if (result->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT))
2353 		goto out;
2354 
2355 	hdrlen = xdr_stream_pos(xdr);
2356 
2357 	acl = NULL;
2358 	if (result->mask & NFS_ACL)
2359 		acl = &result->acl_access;
2360 	aclcnt = NULL;
2361 	if (result->mask & NFS_ACLCNT)
2362 		aclcnt = &result->acl_access_count;
2363 	error = nfsacl_decode(xdr->buf, hdrlen, aclcnt, acl);
2364 	if (unlikely(error <= 0))
2365 		goto out;
2366 
2367 	acl = NULL;
2368 	if (result->mask & NFS_DFACL)
2369 		acl = &result->acl_default;
2370 	aclcnt = NULL;
2371 	if (result->mask & NFS_DFACLCNT)
2372 		aclcnt = &result->acl_default_count;
2373 	error = nfsacl_decode(xdr->buf, hdrlen + error, aclcnt, acl);
2374 	if (unlikely(error <= 0))
2375 		return error;
2376 	error = 0;
2377 out:
2378 	return error;
2379 }
2380 
2381 static int nfs3_xdr_dec_getacl3res(struct rpc_rqst *req,
2382 				   struct xdr_stream *xdr,
2383 				   struct nfs3_getaclres *result)
2384 {
2385 	enum nfs_stat status;
2386 	int error;
2387 
2388 	error = decode_nfsstat3(xdr, &status);
2389 	if (unlikely(error))
2390 		goto out;
2391 	if (status != NFS3_OK)
2392 		goto out_default;
2393 	error = decode_getacl3resok(xdr, result);
2394 out:
2395 	return error;
2396 out_default:
2397 	return nfs3_stat_to_errno(status);
2398 }
2399 
2400 static int nfs3_xdr_dec_setacl3res(struct rpc_rqst *req,
2401 				   struct xdr_stream *xdr,
2402 				   struct nfs_fattr *result)
2403 {
2404 	enum nfs_stat status;
2405 	int error;
2406 
2407 	error = decode_nfsstat3(xdr, &status);
2408 	if (unlikely(error))
2409 		goto out;
2410 	if (status != NFS3_OK)
2411 		goto out_default;
2412 	error = decode_post_op_attr(xdr, result);
2413 out:
2414 	return error;
2415 out_default:
2416 	return nfs3_stat_to_errno(status);
2417 }
2418 
2419 #endif  /* CONFIG_NFS_V3_ACL */
2420 
2421 
2422 /*
2423  * We need to translate between nfs status return values and
2424  * the local errno values which may not be the same.
2425  */
2426 static const struct {
2427 	int stat;
2428 	int errno;
2429 } nfs_errtbl[] = {
2430 	{ NFS_OK,		0		},
2431 	{ NFSERR_PERM,		-EPERM		},
2432 	{ NFSERR_NOENT,		-ENOENT		},
2433 	{ NFSERR_IO,		-errno_NFSERR_IO},
2434 	{ NFSERR_NXIO,		-ENXIO		},
2435 /*	{ NFSERR_EAGAIN,	-EAGAIN		}, */
2436 	{ NFSERR_ACCES,		-EACCES		},
2437 	{ NFSERR_EXIST,		-EEXIST		},
2438 	{ NFSERR_XDEV,		-EXDEV		},
2439 	{ NFSERR_NODEV,		-ENODEV		},
2440 	{ NFSERR_NOTDIR,	-ENOTDIR	},
2441 	{ NFSERR_ISDIR,		-EISDIR		},
2442 	{ NFSERR_INVAL,		-EINVAL		},
2443 	{ NFSERR_FBIG,		-EFBIG		},
2444 	{ NFSERR_NOSPC,		-ENOSPC		},
2445 	{ NFSERR_ROFS,		-EROFS		},
2446 	{ NFSERR_MLINK,		-EMLINK		},
2447 	{ NFSERR_NAMETOOLONG,	-ENAMETOOLONG	},
2448 	{ NFSERR_NOTEMPTY,	-ENOTEMPTY	},
2449 	{ NFSERR_DQUOT,		-EDQUOT		},
2450 	{ NFSERR_STALE,		-ESTALE		},
2451 	{ NFSERR_REMOTE,	-EREMOTE	},
2452 #ifdef EWFLUSH
2453 	{ NFSERR_WFLUSH,	-EWFLUSH	},
2454 #endif
2455 	{ NFSERR_BADHANDLE,	-EBADHANDLE	},
2456 	{ NFSERR_NOT_SYNC,	-ENOTSYNC	},
2457 	{ NFSERR_BAD_COOKIE,	-EBADCOOKIE	},
2458 	{ NFSERR_NOTSUPP,	-ENOTSUPP	},
2459 	{ NFSERR_TOOSMALL,	-ETOOSMALL	},
2460 	{ NFSERR_SERVERFAULT,	-EREMOTEIO	},
2461 	{ NFSERR_BADTYPE,	-EBADTYPE	},
2462 	{ NFSERR_JUKEBOX,	-EJUKEBOX	},
2463 	{ -1,			-EIO		}
2464 };
2465 
2466 /**
2467  * nfs3_stat_to_errno - convert an NFS status code to a local errno
2468  * @status: NFS status code to convert
2469  *
2470  * Returns a local errno value, or -EIO if the NFS status code is
2471  * not recognized.  This function is used jointly by NFSv2 and NFSv3.
2472  */
2473 static int nfs3_stat_to_errno(enum nfs_stat status)
2474 {
2475 	int i;
2476 
2477 	for (i = 0; nfs_errtbl[i].stat != -1; i++) {
2478 		if (nfs_errtbl[i].stat == (int)status)
2479 			return nfs_errtbl[i].errno;
2480 	}
2481 	dprintk("NFS: Unrecognized nfs status value: %u\n", status);
2482 	return nfs_errtbl[i].errno;
2483 }
2484 
2485 
2486 #define PROC(proc, argtype, restype, timer)				\
2487 [NFS3PROC_##proc] = {							\
2488 	.p_proc      = NFS3PROC_##proc,					\
2489 	.p_encode    = (kxdreproc_t)nfs3_xdr_enc_##argtype##3args,	\
2490 	.p_decode    = (kxdrdproc_t)nfs3_xdr_dec_##restype##3res,	\
2491 	.p_arglen    = NFS3_##argtype##args_sz,				\
2492 	.p_replen    = NFS3_##restype##res_sz,				\
2493 	.p_timer     = timer,						\
2494 	.p_statidx   = NFS3PROC_##proc,					\
2495 	.p_name      = #proc,						\
2496 	}
2497 
2498 struct rpc_procinfo	nfs3_procedures[] = {
2499 	PROC(GETATTR,		getattr,	getattr,	1),
2500 	PROC(SETATTR,		setattr,	setattr,	0),
2501 	PROC(LOOKUP,		lookup,		lookup,		2),
2502 	PROC(ACCESS,		access,		access,		1),
2503 	PROC(READLINK,		readlink,	readlink,	3),
2504 	PROC(READ,		read,		read,		3),
2505 	PROC(WRITE,		write,		write,		4),
2506 	PROC(CREATE,		create,		create,		0),
2507 	PROC(MKDIR,		mkdir,		create,		0),
2508 	PROC(SYMLINK,		symlink,	create,		0),
2509 	PROC(MKNOD,		mknod,		create,		0),
2510 	PROC(REMOVE,		remove,		remove,		0),
2511 	PROC(RMDIR,		lookup,		setattr,	0),
2512 	PROC(RENAME,		rename,		rename,		0),
2513 	PROC(LINK,		link,		link,		0),
2514 	PROC(READDIR,		readdir,	readdir,	3),
2515 	PROC(READDIRPLUS,	readdirplus,	readdir,	3),
2516 	PROC(FSSTAT,		getattr,	fsstat,		0),
2517 	PROC(FSINFO,		getattr,	fsinfo,		0),
2518 	PROC(PATHCONF,		getattr,	pathconf,	0),
2519 	PROC(COMMIT,		commit,		commit,		5),
2520 };
2521 
2522 const struct rpc_version nfs_version3 = {
2523 	.number			= 3,
2524 	.nrprocs		= ARRAY_SIZE(nfs3_procedures),
2525 	.procs			= nfs3_procedures
2526 };
2527 
2528 #ifdef CONFIG_NFS_V3_ACL
2529 static struct rpc_procinfo	nfs3_acl_procedures[] = {
2530 	[ACLPROC3_GETACL] = {
2531 		.p_proc = ACLPROC3_GETACL,
2532 		.p_encode = (kxdreproc_t)nfs3_xdr_enc_getacl3args,
2533 		.p_decode = (kxdrdproc_t)nfs3_xdr_dec_getacl3res,
2534 		.p_arglen = ACL3_getaclargs_sz,
2535 		.p_replen = ACL3_getaclres_sz,
2536 		.p_timer = 1,
2537 		.p_name = "GETACL",
2538 	},
2539 	[ACLPROC3_SETACL] = {
2540 		.p_proc = ACLPROC3_SETACL,
2541 		.p_encode = (kxdreproc_t)nfs3_xdr_enc_setacl3args,
2542 		.p_decode = (kxdrdproc_t)nfs3_xdr_dec_setacl3res,
2543 		.p_arglen = ACL3_setaclargs_sz,
2544 		.p_replen = ACL3_setaclres_sz,
2545 		.p_timer = 0,
2546 		.p_name = "SETACL",
2547 	},
2548 };
2549 
2550 const struct rpc_version nfsacl_version3 = {
2551 	.number			= 3,
2552 	.nrprocs		= sizeof(nfs3_acl_procedures)/
2553 				  sizeof(nfs3_acl_procedures[0]),
2554 	.procs			= nfs3_acl_procedures,
2555 };
2556 #endif  /* CONFIG_NFS_V3_ACL */
2557