xref: /openbmc/linux/fs/nfs/nfs3xdr.c (revision e2028c8e)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * linux/fs/nfs/nfs3xdr.c
4  *
5  * XDR functions to encode/decode NFSv3 RPC arguments and results.
6  *
7  * Copyright (C) 1996, 1997 Olaf Kirch
8  */
9 
10 #include <linux/param.h>
11 #include <linux/time.h>
12 #include <linux/mm.h>
13 #include <linux/errno.h>
14 #include <linux/string.h>
15 #include <linux/in.h>
16 #include <linux/pagemap.h>
17 #include <linux/proc_fs.h>
18 #include <linux/kdev_t.h>
19 #include <linux/sunrpc/clnt.h>
20 #include <linux/nfs.h>
21 #include <linux/nfs3.h>
22 #include <linux/nfs_fs.h>
23 #include <linux/nfsacl.h>
24 #include "nfstrace.h"
25 #include "internal.h"
26 
27 #define NFSDBG_FACILITY		NFSDBG_XDR
28 
29 /* Mapping from NFS error code to "errno" error code. */
30 #define errno_NFSERR_IO		EIO
31 
32 /*
33  * Declare the space requirements for NFS arguments and replies as
34  * number of 32bit-words
35  */
36 #define NFS3_fhandle_sz		(1+16)
37 #define NFS3_fh_sz		(NFS3_fhandle_sz)	/* shorthand */
38 #define NFS3_sattr_sz		(15)
39 #define NFS3_filename_sz	(1+(NFS3_MAXNAMLEN>>2))
40 #define NFS3_path_sz		(1+(NFS3_MAXPATHLEN>>2))
41 #define NFS3_fattr_sz		(21)
42 #define NFS3_cookieverf_sz	(NFS3_COOKIEVERFSIZE>>2)
43 #define NFS3_wcc_attr_sz	(6)
44 #define NFS3_pre_op_attr_sz	(1+NFS3_wcc_attr_sz)
45 #define NFS3_post_op_attr_sz	(1+NFS3_fattr_sz)
46 #define NFS3_wcc_data_sz	(NFS3_pre_op_attr_sz+NFS3_post_op_attr_sz)
47 #define NFS3_diropargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
48 
49 #define NFS3_getattrargs_sz	(NFS3_fh_sz)
50 #define NFS3_setattrargs_sz	(NFS3_fh_sz+NFS3_sattr_sz+3)
51 #define NFS3_lookupargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
52 #define NFS3_accessargs_sz	(NFS3_fh_sz+1)
53 #define NFS3_readlinkargs_sz	(NFS3_fh_sz)
54 #define NFS3_readargs_sz	(NFS3_fh_sz+3)
55 #define NFS3_writeargs_sz	(NFS3_fh_sz+5)
56 #define NFS3_createargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
57 #define NFS3_mkdirargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
58 #define NFS3_symlinkargs_sz	(NFS3_diropargs_sz+1+NFS3_sattr_sz)
59 #define NFS3_mknodargs_sz	(NFS3_diropargs_sz+2+NFS3_sattr_sz)
60 #define NFS3_removeargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
61 #define NFS3_renameargs_sz	(NFS3_diropargs_sz+NFS3_diropargs_sz)
62 #define NFS3_linkargs_sz		(NFS3_fh_sz+NFS3_diropargs_sz)
63 #define NFS3_readdirargs_sz	(NFS3_fh_sz+NFS3_cookieverf_sz+3)
64 #define NFS3_readdirplusargs_sz	(NFS3_fh_sz+NFS3_cookieverf_sz+4)
65 #define NFS3_commitargs_sz	(NFS3_fh_sz+3)
66 
67 #define NFS3_getattrres_sz	(1+NFS3_fattr_sz)
68 #define NFS3_setattrres_sz	(1+NFS3_wcc_data_sz)
69 #define NFS3_removeres_sz	(NFS3_setattrres_sz)
70 #define NFS3_lookupres_sz	(1+NFS3_fh_sz+(2 * NFS3_post_op_attr_sz))
71 #define NFS3_accessres_sz	(1+NFS3_post_op_attr_sz+1)
72 #define NFS3_readlinkres_sz	(1+NFS3_post_op_attr_sz+1+1)
73 #define NFS3_readres_sz		(1+NFS3_post_op_attr_sz+3+1)
74 #define NFS3_writeres_sz	(1+NFS3_wcc_data_sz+4)
75 #define NFS3_createres_sz	(1+NFS3_fh_sz+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
76 #define NFS3_renameres_sz	(1+(2 * NFS3_wcc_data_sz))
77 #define NFS3_linkres_sz		(1+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
78 #define NFS3_readdirres_sz	(1+NFS3_post_op_attr_sz+2+1)
79 #define NFS3_fsstatres_sz	(1+NFS3_post_op_attr_sz+13)
80 #define NFS3_fsinfores_sz	(1+NFS3_post_op_attr_sz+12)
81 #define NFS3_pathconfres_sz	(1+NFS3_post_op_attr_sz+6)
82 #define NFS3_commitres_sz	(1+NFS3_wcc_data_sz+2)
83 
84 #define ACL3_getaclargs_sz	(NFS3_fh_sz+1)
85 #define ACL3_setaclargs_sz	(NFS3_fh_sz+1+ \
86 				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE))
87 #define ACL3_getaclres_sz	(1+NFS3_post_op_attr_sz+1+ \
88 				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE)+1)
89 #define ACL3_setaclres_sz	(1+NFS3_post_op_attr_sz)
90 
91 static int nfs3_stat_to_errno(enum nfs_stat);
92 
93 /*
94  * Map file type to S_IFMT bits
95  */
96 static const umode_t nfs_type2fmt[] = {
97 	[NF3BAD] = 0,
98 	[NF3REG] = S_IFREG,
99 	[NF3DIR] = S_IFDIR,
100 	[NF3BLK] = S_IFBLK,
101 	[NF3CHR] = S_IFCHR,
102 	[NF3LNK] = S_IFLNK,
103 	[NF3SOCK] = S_IFSOCK,
104 	[NF3FIFO] = S_IFIFO,
105 };
106 
107 static struct user_namespace *rpc_userns(const struct rpc_clnt *clnt)
108 {
109 	if (clnt && clnt->cl_cred)
110 		return clnt->cl_cred->user_ns;
111 	return &init_user_ns;
112 }
113 
114 static struct user_namespace *rpc_rqst_userns(const struct rpc_rqst *rqstp)
115 {
116 	if (rqstp->rq_task)
117 		return rpc_userns(rqstp->rq_task->tk_client);
118 	return &init_user_ns;
119 }
120 
121 /*
122  * Encode/decode NFSv3 basic data types
123  *
124  * Basic NFSv3 data types are defined in section 2.5 of RFC 1813:
125  * "NFS Version 3 Protocol Specification".
126  *
127  * Not all basic data types have their own encoding and decoding
128  * functions.  For run-time efficiency, some data types are encoded
129  * or decoded inline.
130  */
131 
132 static void encode_uint32(struct xdr_stream *xdr, u32 value)
133 {
134 	__be32 *p = xdr_reserve_space(xdr, 4);
135 	*p = cpu_to_be32(value);
136 }
137 
138 static int decode_uint32(struct xdr_stream *xdr, u32 *value)
139 {
140 	__be32 *p;
141 
142 	p = xdr_inline_decode(xdr, 4);
143 	if (unlikely(!p))
144 		return -EIO;
145 	*value = be32_to_cpup(p);
146 	return 0;
147 }
148 
149 static int decode_uint64(struct xdr_stream *xdr, u64 *value)
150 {
151 	__be32 *p;
152 
153 	p = xdr_inline_decode(xdr, 8);
154 	if (unlikely(!p))
155 		return -EIO;
156 	xdr_decode_hyper(p, value);
157 	return 0;
158 }
159 
160 /*
161  * fileid3
162  *
163  *	typedef uint64 fileid3;
164  */
165 static __be32 *xdr_decode_fileid3(__be32 *p, u64 *fileid)
166 {
167 	return xdr_decode_hyper(p, fileid);
168 }
169 
170 static int decode_fileid3(struct xdr_stream *xdr, u64 *fileid)
171 {
172 	return decode_uint64(xdr, fileid);
173 }
174 
175 /*
176  * filename3
177  *
178  *	typedef string filename3<>;
179  */
180 static void encode_filename3(struct xdr_stream *xdr,
181 			     const char *name, u32 length)
182 {
183 	__be32 *p;
184 
185 	WARN_ON_ONCE(length > NFS3_MAXNAMLEN);
186 	p = xdr_reserve_space(xdr, 4 + length);
187 	xdr_encode_opaque(p, name, length);
188 }
189 
190 static int decode_inline_filename3(struct xdr_stream *xdr,
191 				   const char **name, u32 *length)
192 {
193 	__be32 *p;
194 	u32 count;
195 
196 	p = xdr_inline_decode(xdr, 4);
197 	if (unlikely(!p))
198 		return -EIO;
199 	count = be32_to_cpup(p);
200 	if (count > NFS3_MAXNAMLEN)
201 		goto out_nametoolong;
202 	p = xdr_inline_decode(xdr, count);
203 	if (unlikely(!p))
204 		return -EIO;
205 	*name = (const char *)p;
206 	*length = count;
207 	return 0;
208 
209 out_nametoolong:
210 	dprintk("NFS: returned filename too long: %u\n", count);
211 	return -ENAMETOOLONG;
212 }
213 
214 /*
215  * nfspath3
216  *
217  *	typedef string nfspath3<>;
218  */
219 static void encode_nfspath3(struct xdr_stream *xdr, struct page **pages,
220 			    const u32 length)
221 {
222 	encode_uint32(xdr, length);
223 	xdr_write_pages(xdr, pages, 0, length);
224 }
225 
226 static int decode_nfspath3(struct xdr_stream *xdr)
227 {
228 	u32 recvd, count;
229 	__be32 *p;
230 
231 	p = xdr_inline_decode(xdr, 4);
232 	if (unlikely(!p))
233 		return -EIO;
234 	count = be32_to_cpup(p);
235 	if (unlikely(count >= xdr->buf->page_len || count > NFS3_MAXPATHLEN))
236 		goto out_nametoolong;
237 	recvd = xdr_read_pages(xdr, count);
238 	if (unlikely(count > recvd))
239 		goto out_cheating;
240 	xdr_terminate_string(xdr->buf, count);
241 	return 0;
242 
243 out_nametoolong:
244 	dprintk("NFS: returned pathname too long: %u\n", count);
245 	return -ENAMETOOLONG;
246 out_cheating:
247 	dprintk("NFS: server cheating in pathname result: "
248 		"count %u > recvd %u\n", count, recvd);
249 	return -EIO;
250 }
251 
252 /*
253  * cookie3
254  *
255  *	typedef uint64 cookie3
256  */
257 static __be32 *xdr_encode_cookie3(__be32 *p, u64 cookie)
258 {
259 	return xdr_encode_hyper(p, cookie);
260 }
261 
262 static int decode_cookie3(struct xdr_stream *xdr, u64 *cookie)
263 {
264 	return decode_uint64(xdr, cookie);
265 }
266 
267 /*
268  * cookieverf3
269  *
270  *	typedef opaque cookieverf3[NFS3_COOKIEVERFSIZE];
271  */
272 static __be32 *xdr_encode_cookieverf3(__be32 *p, const __be32 *verifier)
273 {
274 	memcpy(p, verifier, NFS3_COOKIEVERFSIZE);
275 	return p + XDR_QUADLEN(NFS3_COOKIEVERFSIZE);
276 }
277 
278 static int decode_cookieverf3(struct xdr_stream *xdr, __be32 *verifier)
279 {
280 	__be32 *p;
281 
282 	p = xdr_inline_decode(xdr, NFS3_COOKIEVERFSIZE);
283 	if (unlikely(!p))
284 		return -EIO;
285 	memcpy(verifier, p, NFS3_COOKIEVERFSIZE);
286 	return 0;
287 }
288 
289 /*
290  * createverf3
291  *
292  *	typedef opaque createverf3[NFS3_CREATEVERFSIZE];
293  */
294 static void encode_createverf3(struct xdr_stream *xdr, const __be32 *verifier)
295 {
296 	__be32 *p;
297 
298 	p = xdr_reserve_space(xdr, NFS3_CREATEVERFSIZE);
299 	memcpy(p, verifier, NFS3_CREATEVERFSIZE);
300 }
301 
302 static int decode_writeverf3(struct xdr_stream *xdr, struct nfs_write_verifier *verifier)
303 {
304 	__be32 *p;
305 
306 	p = xdr_inline_decode(xdr, NFS3_WRITEVERFSIZE);
307 	if (unlikely(!p))
308 		return -EIO;
309 	memcpy(verifier->data, p, NFS3_WRITEVERFSIZE);
310 	return 0;
311 }
312 
313 /*
314  * size3
315  *
316  *	typedef uint64 size3;
317  */
318 static __be32 *xdr_decode_size3(__be32 *p, u64 *size)
319 {
320 	return xdr_decode_hyper(p, size);
321 }
322 
323 /*
324  * nfsstat3
325  *
326  *	enum nfsstat3 {
327  *		NFS3_OK = 0,
328  *		...
329  *	}
330  */
331 #define NFS3_OK		NFS_OK
332 
333 static int decode_nfsstat3(struct xdr_stream *xdr, enum nfs_stat *status)
334 {
335 	__be32 *p;
336 
337 	p = xdr_inline_decode(xdr, 4);
338 	if (unlikely(!p))
339 		return -EIO;
340 	if (unlikely(*p != cpu_to_be32(NFS3_OK)))
341 		goto out_status;
342 	*status = 0;
343 	return 0;
344 out_status:
345 	*status = be32_to_cpup(p);
346 	trace_nfs_xdr_status(xdr, (int)*status);
347 	return 0;
348 }
349 
350 /*
351  * ftype3
352  *
353  *	enum ftype3 {
354  *		NF3REG	= 1,
355  *		NF3DIR	= 2,
356  *		NF3BLK	= 3,
357  *		NF3CHR	= 4,
358  *		NF3LNK	= 5,
359  *		NF3SOCK	= 6,
360  *		NF3FIFO	= 7
361  *	};
362  */
363 static void encode_ftype3(struct xdr_stream *xdr, const u32 type)
364 {
365 	encode_uint32(xdr, type);
366 }
367 
368 static __be32 *xdr_decode_ftype3(__be32 *p, umode_t *mode)
369 {
370 	u32 type;
371 
372 	type = be32_to_cpup(p++);
373 	if (type > NF3FIFO)
374 		type = NF3NON;
375 	*mode = nfs_type2fmt[type];
376 	return p;
377 }
378 
379 /*
380  * specdata3
381  *
382  *     struct specdata3 {
383  *             uint32  specdata1;
384  *             uint32  specdata2;
385  *     };
386  */
387 static void encode_specdata3(struct xdr_stream *xdr, const dev_t rdev)
388 {
389 	__be32 *p;
390 
391 	p = xdr_reserve_space(xdr, 8);
392 	*p++ = cpu_to_be32(MAJOR(rdev));
393 	*p = cpu_to_be32(MINOR(rdev));
394 }
395 
396 static __be32 *xdr_decode_specdata3(__be32 *p, dev_t *rdev)
397 {
398 	unsigned int major, minor;
399 
400 	major = be32_to_cpup(p++);
401 	minor = be32_to_cpup(p++);
402 	*rdev = MKDEV(major, minor);
403 	if (MAJOR(*rdev) != major || MINOR(*rdev) != minor)
404 		*rdev = 0;
405 	return p;
406 }
407 
408 /*
409  * nfs_fh3
410  *
411  *	struct nfs_fh3 {
412  *		opaque       data<NFS3_FHSIZE>;
413  *	};
414  */
415 static void encode_nfs_fh3(struct xdr_stream *xdr, const struct nfs_fh *fh)
416 {
417 	__be32 *p;
418 
419 	WARN_ON_ONCE(fh->size > NFS3_FHSIZE);
420 	p = xdr_reserve_space(xdr, 4 + fh->size);
421 	xdr_encode_opaque(p, fh->data, fh->size);
422 }
423 
424 static int decode_nfs_fh3(struct xdr_stream *xdr, struct nfs_fh *fh)
425 {
426 	u32 length;
427 	__be32 *p;
428 
429 	p = xdr_inline_decode(xdr, 4);
430 	if (unlikely(!p))
431 		return -EIO;
432 	length = be32_to_cpup(p++);
433 	if (unlikely(length > NFS3_FHSIZE))
434 		goto out_toobig;
435 	p = xdr_inline_decode(xdr, length);
436 	if (unlikely(!p))
437 		return -EIO;
438 	fh->size = length;
439 	memcpy(fh->data, p, length);
440 	return 0;
441 out_toobig:
442 	dprintk("NFS: file handle size (%u) too big\n", length);
443 	return -E2BIG;
444 }
445 
446 static void zero_nfs_fh3(struct nfs_fh *fh)
447 {
448 	memset(fh, 0, sizeof(*fh));
449 }
450 
451 /*
452  * nfstime3
453  *
454  *	struct nfstime3 {
455  *		uint32	seconds;
456  *		uint32	nseconds;
457  *	};
458  */
459 static __be32 *xdr_encode_nfstime3(__be32 *p, const struct timespec64 *timep)
460 {
461 	*p++ = cpu_to_be32((u32)timep->tv_sec);
462 	*p++ = cpu_to_be32(timep->tv_nsec);
463 	return p;
464 }
465 
466 static __be32 *xdr_decode_nfstime3(__be32 *p, struct timespec64 *timep)
467 {
468 	timep->tv_sec = be32_to_cpup(p++);
469 	timep->tv_nsec = be32_to_cpup(p++);
470 	return p;
471 }
472 
473 /*
474  * sattr3
475  *
476  *	enum time_how {
477  *		DONT_CHANGE		= 0,
478  *		SET_TO_SERVER_TIME	= 1,
479  *		SET_TO_CLIENT_TIME	= 2
480  *	};
481  *
482  *	union set_mode3 switch (bool set_it) {
483  *	case TRUE:
484  *		mode3	mode;
485  *	default:
486  *		void;
487  *	};
488  *
489  *	union set_uid3 switch (bool set_it) {
490  *	case TRUE:
491  *		uid3	uid;
492  *	default:
493  *		void;
494  *	};
495  *
496  *	union set_gid3 switch (bool set_it) {
497  *	case TRUE:
498  *		gid3	gid;
499  *	default:
500  *		void;
501  *	};
502  *
503  *	union set_size3 switch (bool set_it) {
504  *	case TRUE:
505  *		size3	size;
506  *	default:
507  *		void;
508  *	};
509  *
510  *	union set_atime switch (time_how set_it) {
511  *	case SET_TO_CLIENT_TIME:
512  *		nfstime3	atime;
513  *	default:
514  *		void;
515  *	};
516  *
517  *	union set_mtime switch (time_how set_it) {
518  *	case SET_TO_CLIENT_TIME:
519  *		nfstime3  mtime;
520  *	default:
521  *		void;
522  *	};
523  *
524  *	struct sattr3 {
525  *		set_mode3	mode;
526  *		set_uid3	uid;
527  *		set_gid3	gid;
528  *		set_size3	size;
529  *		set_atime	atime;
530  *		set_mtime	mtime;
531  *	};
532  */
533 static void encode_sattr3(struct xdr_stream *xdr, const struct iattr *attr,
534 		struct user_namespace *userns)
535 {
536 	u32 nbytes;
537 	__be32 *p;
538 
539 	/*
540 	 * In order to make only a single xdr_reserve_space() call,
541 	 * pre-compute the total number of bytes to be reserved.
542 	 * Six boolean values, one for each set_foo field, are always
543 	 * present in the encoded result, so start there.
544 	 */
545 	nbytes = 6 * 4;
546 	if (attr->ia_valid & ATTR_MODE)
547 		nbytes += 4;
548 	if (attr->ia_valid & ATTR_UID)
549 		nbytes += 4;
550 	if (attr->ia_valid & ATTR_GID)
551 		nbytes += 4;
552 	if (attr->ia_valid & ATTR_SIZE)
553 		nbytes += 8;
554 	if (attr->ia_valid & ATTR_ATIME_SET)
555 		nbytes += 8;
556 	if (attr->ia_valid & ATTR_MTIME_SET)
557 		nbytes += 8;
558 	p = xdr_reserve_space(xdr, nbytes);
559 
560 	if (attr->ia_valid & ATTR_MODE) {
561 		*p++ = xdr_one;
562 		*p++ = cpu_to_be32(attr->ia_mode & S_IALLUGO);
563 	} else
564 		*p++ = xdr_zero;
565 
566 	if (attr->ia_valid & ATTR_UID) {
567 		*p++ = xdr_one;
568 		*p++ = cpu_to_be32(from_kuid_munged(userns, attr->ia_uid));
569 	} else
570 		*p++ = xdr_zero;
571 
572 	if (attr->ia_valid & ATTR_GID) {
573 		*p++ = xdr_one;
574 		*p++ = cpu_to_be32(from_kgid_munged(userns, attr->ia_gid));
575 	} else
576 		*p++ = xdr_zero;
577 
578 	if (attr->ia_valid & ATTR_SIZE) {
579 		*p++ = xdr_one;
580 		p = xdr_encode_hyper(p, (u64)attr->ia_size);
581 	} else
582 		*p++ = xdr_zero;
583 
584 	if (attr->ia_valid & ATTR_ATIME_SET) {
585 		*p++ = xdr_two;
586 		p = xdr_encode_nfstime3(p, &attr->ia_atime);
587 	} else if (attr->ia_valid & ATTR_ATIME) {
588 		*p++ = xdr_one;
589 	} else
590 		*p++ = xdr_zero;
591 
592 	if (attr->ia_valid & ATTR_MTIME_SET) {
593 		*p++ = xdr_two;
594 		xdr_encode_nfstime3(p, &attr->ia_mtime);
595 	} else if (attr->ia_valid & ATTR_MTIME) {
596 		*p = xdr_one;
597 	} else
598 		*p = xdr_zero;
599 }
600 
601 /*
602  * fattr3
603  *
604  *	struct fattr3 {
605  *		ftype3		type;
606  *		mode3		mode;
607  *		uint32		nlink;
608  *		uid3		uid;
609  *		gid3		gid;
610  *		size3		size;
611  *		size3		used;
612  *		specdata3	rdev;
613  *		uint64		fsid;
614  *		fileid3		fileid;
615  *		nfstime3	atime;
616  *		nfstime3	mtime;
617  *		nfstime3	ctime;
618  *	};
619  */
620 static int decode_fattr3(struct xdr_stream *xdr, struct nfs_fattr *fattr,
621 		struct user_namespace *userns)
622 {
623 	umode_t fmode;
624 	__be32 *p;
625 
626 	p = xdr_inline_decode(xdr, NFS3_fattr_sz << 2);
627 	if (unlikely(!p))
628 		return -EIO;
629 
630 	p = xdr_decode_ftype3(p, &fmode);
631 
632 	fattr->mode = (be32_to_cpup(p++) & ~S_IFMT) | fmode;
633 	fattr->nlink = be32_to_cpup(p++);
634 	fattr->uid = make_kuid(userns, be32_to_cpup(p++));
635 	if (!uid_valid(fattr->uid))
636 		goto out_uid;
637 	fattr->gid = make_kgid(userns, be32_to_cpup(p++));
638 	if (!gid_valid(fattr->gid))
639 		goto out_gid;
640 
641 	p = xdr_decode_size3(p, &fattr->size);
642 	p = xdr_decode_size3(p, &fattr->du.nfs3.used);
643 	p = xdr_decode_specdata3(p, &fattr->rdev);
644 
645 	p = xdr_decode_hyper(p, &fattr->fsid.major);
646 	fattr->fsid.minor = 0;
647 
648 	p = xdr_decode_fileid3(p, &fattr->fileid);
649 	p = xdr_decode_nfstime3(p, &fattr->atime);
650 	p = xdr_decode_nfstime3(p, &fattr->mtime);
651 	xdr_decode_nfstime3(p, &fattr->ctime);
652 	fattr->change_attr = nfs_timespec_to_change_attr(&fattr->ctime);
653 
654 	fattr->valid |= NFS_ATTR_FATTR_V3;
655 	return 0;
656 out_uid:
657 	dprintk("NFS: returned invalid uid\n");
658 	return -EINVAL;
659 out_gid:
660 	dprintk("NFS: returned invalid gid\n");
661 	return -EINVAL;
662 }
663 
664 /*
665  * post_op_attr
666  *
667  *	union post_op_attr switch (bool attributes_follow) {
668  *	case TRUE:
669  *		fattr3	attributes;
670  *	case FALSE:
671  *		void;
672  *	};
673  */
674 static int decode_post_op_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr,
675 		struct user_namespace *userns)
676 {
677 	__be32 *p;
678 
679 	p = xdr_inline_decode(xdr, 4);
680 	if (unlikely(!p))
681 		return -EIO;
682 	if (*p != xdr_zero)
683 		return decode_fattr3(xdr, fattr, userns);
684 	return 0;
685 }
686 
687 /*
688  * wcc_attr
689  *	struct wcc_attr {
690  *		size3		size;
691  *		nfstime3	mtime;
692  *		nfstime3	ctime;
693  *	};
694  */
695 static int decode_wcc_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
696 {
697 	__be32 *p;
698 
699 	p = xdr_inline_decode(xdr, NFS3_wcc_attr_sz << 2);
700 	if (unlikely(!p))
701 		return -EIO;
702 
703 	fattr->valid |= NFS_ATTR_FATTR_PRESIZE
704 		| NFS_ATTR_FATTR_PRECHANGE
705 		| NFS_ATTR_FATTR_PREMTIME
706 		| NFS_ATTR_FATTR_PRECTIME;
707 
708 	p = xdr_decode_size3(p, &fattr->pre_size);
709 	p = xdr_decode_nfstime3(p, &fattr->pre_mtime);
710 	xdr_decode_nfstime3(p, &fattr->pre_ctime);
711 	fattr->pre_change_attr = nfs_timespec_to_change_attr(&fattr->pre_ctime);
712 
713 	return 0;
714 }
715 
716 /*
717  * pre_op_attr
718  *	union pre_op_attr switch (bool attributes_follow) {
719  *	case TRUE:
720  *		wcc_attr	attributes;
721  *	case FALSE:
722  *		void;
723  *	};
724  *
725  * wcc_data
726  *
727  *	struct wcc_data {
728  *		pre_op_attr	before;
729  *		post_op_attr	after;
730  *	};
731  */
732 static int decode_pre_op_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
733 {
734 	__be32 *p;
735 
736 	p = xdr_inline_decode(xdr, 4);
737 	if (unlikely(!p))
738 		return -EIO;
739 	if (*p != xdr_zero)
740 		return decode_wcc_attr(xdr, fattr);
741 	return 0;
742 }
743 
744 static int decode_wcc_data(struct xdr_stream *xdr, struct nfs_fattr *fattr,
745 		struct user_namespace *userns)
746 {
747 	int error;
748 
749 	error = decode_pre_op_attr(xdr, fattr);
750 	if (unlikely(error))
751 		goto out;
752 	error = decode_post_op_attr(xdr, fattr, userns);
753 out:
754 	return error;
755 }
756 
757 /*
758  * post_op_fh3
759  *
760  *	union post_op_fh3 switch (bool handle_follows) {
761  *	case TRUE:
762  *		nfs_fh3  handle;
763  *	case FALSE:
764  *		void;
765  *	};
766  */
767 static int decode_post_op_fh3(struct xdr_stream *xdr, struct nfs_fh *fh)
768 {
769 	__be32 *p = xdr_inline_decode(xdr, 4);
770 	if (unlikely(!p))
771 		return -EIO;
772 	if (*p != xdr_zero)
773 		return decode_nfs_fh3(xdr, fh);
774 	zero_nfs_fh3(fh);
775 	return 0;
776 }
777 
778 /*
779  * diropargs3
780  *
781  *	struct diropargs3 {
782  *		nfs_fh3		dir;
783  *		filename3	name;
784  *	};
785  */
786 static void encode_diropargs3(struct xdr_stream *xdr, const struct nfs_fh *fh,
787 			      const char *name, u32 length)
788 {
789 	encode_nfs_fh3(xdr, fh);
790 	encode_filename3(xdr, name, length);
791 }
792 
793 
794 /*
795  * NFSv3 XDR encode functions
796  *
797  * NFSv3 argument types are defined in section 3.3 of RFC 1813:
798  * "NFS Version 3 Protocol Specification".
799  */
800 
801 /*
802  * 3.3.1  GETATTR3args
803  *
804  *	struct GETATTR3args {
805  *		nfs_fh3  object;
806  *	};
807  */
808 static void nfs3_xdr_enc_getattr3args(struct rpc_rqst *req,
809 				      struct xdr_stream *xdr,
810 				      const void *data)
811 {
812 	const struct nfs_fh *fh = data;
813 
814 	encode_nfs_fh3(xdr, fh);
815 }
816 
817 /*
818  * 3.3.2  SETATTR3args
819  *
820  *	union sattrguard3 switch (bool check) {
821  *	case TRUE:
822  *		nfstime3  obj_ctime;
823  *	case FALSE:
824  *		void;
825  *	};
826  *
827  *	struct SETATTR3args {
828  *		nfs_fh3		object;
829  *		sattr3		new_attributes;
830  *		sattrguard3	guard;
831  *	};
832  */
833 static void encode_sattrguard3(struct xdr_stream *xdr,
834 			       const struct nfs3_sattrargs *args)
835 {
836 	__be32 *p;
837 
838 	if (args->guard) {
839 		p = xdr_reserve_space(xdr, 4 + 8);
840 		*p++ = xdr_one;
841 		xdr_encode_nfstime3(p, &args->guardtime);
842 	} else {
843 		p = xdr_reserve_space(xdr, 4);
844 		*p = xdr_zero;
845 	}
846 }
847 
848 static void nfs3_xdr_enc_setattr3args(struct rpc_rqst *req,
849 				      struct xdr_stream *xdr,
850 				      const void *data)
851 {
852 	const struct nfs3_sattrargs *args = data;
853 	encode_nfs_fh3(xdr, args->fh);
854 	encode_sattr3(xdr, args->sattr, rpc_rqst_userns(req));
855 	encode_sattrguard3(xdr, args);
856 }
857 
858 /*
859  * 3.3.3  LOOKUP3args
860  *
861  *	struct LOOKUP3args {
862  *		diropargs3  what;
863  *	};
864  */
865 static void nfs3_xdr_enc_lookup3args(struct rpc_rqst *req,
866 				     struct xdr_stream *xdr,
867 				     const void *data)
868 {
869 	const struct nfs3_diropargs *args = data;
870 
871 	encode_diropargs3(xdr, args->fh, args->name, args->len);
872 }
873 
874 /*
875  * 3.3.4  ACCESS3args
876  *
877  *	struct ACCESS3args {
878  *		nfs_fh3		object;
879  *		uint32		access;
880  *	};
881  */
882 static void encode_access3args(struct xdr_stream *xdr,
883 			       const struct nfs3_accessargs *args)
884 {
885 	encode_nfs_fh3(xdr, args->fh);
886 	encode_uint32(xdr, args->access);
887 }
888 
889 static void nfs3_xdr_enc_access3args(struct rpc_rqst *req,
890 				     struct xdr_stream *xdr,
891 				     const void *data)
892 {
893 	const struct nfs3_accessargs *args = data;
894 
895 	encode_access3args(xdr, args);
896 }
897 
898 /*
899  * 3.3.5  READLINK3args
900  *
901  *	struct READLINK3args {
902  *		nfs_fh3	symlink;
903  *	};
904  */
905 static void nfs3_xdr_enc_readlink3args(struct rpc_rqst *req,
906 				       struct xdr_stream *xdr,
907 				       const void *data)
908 {
909 	const struct nfs3_readlinkargs *args = data;
910 
911 	encode_nfs_fh3(xdr, args->fh);
912 	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
913 				args->pglen, NFS3_readlinkres_sz);
914 }
915 
916 /*
917  * 3.3.6  READ3args
918  *
919  *	struct READ3args {
920  *		nfs_fh3		file;
921  *		offset3		offset;
922  *		count3		count;
923  *	};
924  */
925 static void encode_read3args(struct xdr_stream *xdr,
926 			     const struct nfs_pgio_args *args)
927 {
928 	__be32 *p;
929 
930 	encode_nfs_fh3(xdr, args->fh);
931 
932 	p = xdr_reserve_space(xdr, 8 + 4);
933 	p = xdr_encode_hyper(p, args->offset);
934 	*p = cpu_to_be32(args->count);
935 }
936 
937 static void nfs3_xdr_enc_read3args(struct rpc_rqst *req,
938 				   struct xdr_stream *xdr,
939 				   const void *data)
940 {
941 	const struct nfs_pgio_args *args = data;
942 	unsigned int replen = args->replen ? args->replen : NFS3_readres_sz;
943 
944 	encode_read3args(xdr, args);
945 	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
946 				args->count, replen);
947 	req->rq_rcv_buf.flags |= XDRBUF_READ;
948 }
949 
950 /*
951  * 3.3.7  WRITE3args
952  *
953  *	enum stable_how {
954  *		UNSTABLE  = 0,
955  *		DATA_SYNC = 1,
956  *		FILE_SYNC = 2
957  *	};
958  *
959  *	struct WRITE3args {
960  *		nfs_fh3		file;
961  *		offset3		offset;
962  *		count3		count;
963  *		stable_how	stable;
964  *		opaque		data<>;
965  *	};
966  */
967 static void encode_write3args(struct xdr_stream *xdr,
968 			      const struct nfs_pgio_args *args)
969 {
970 	__be32 *p;
971 
972 	encode_nfs_fh3(xdr, args->fh);
973 
974 	p = xdr_reserve_space(xdr, 8 + 4 + 4 + 4);
975 	p = xdr_encode_hyper(p, args->offset);
976 	*p++ = cpu_to_be32(args->count);
977 	*p++ = cpu_to_be32(args->stable);
978 	*p = cpu_to_be32(args->count);
979 	xdr_write_pages(xdr, args->pages, args->pgbase, args->count);
980 }
981 
982 static void nfs3_xdr_enc_write3args(struct rpc_rqst *req,
983 				    struct xdr_stream *xdr,
984 				    const void *data)
985 {
986 	const struct nfs_pgio_args *args = data;
987 
988 	encode_write3args(xdr, args);
989 	xdr->buf->flags |= XDRBUF_WRITE;
990 }
991 
992 /*
993  * 3.3.8  CREATE3args
994  *
995  *	enum createmode3 {
996  *		UNCHECKED = 0,
997  *		GUARDED   = 1,
998  *		EXCLUSIVE = 2
999  *	};
1000  *
1001  *	union createhow3 switch (createmode3 mode) {
1002  *	case UNCHECKED:
1003  *	case GUARDED:
1004  *		sattr3       obj_attributes;
1005  *	case EXCLUSIVE:
1006  *		createverf3  verf;
1007  *	};
1008  *
1009  *	struct CREATE3args {
1010  *		diropargs3	where;
1011  *		createhow3	how;
1012  *	};
1013  */
1014 static void encode_createhow3(struct xdr_stream *xdr,
1015 			      const struct nfs3_createargs *args,
1016 			      struct user_namespace *userns)
1017 {
1018 	encode_uint32(xdr, args->createmode);
1019 	switch (args->createmode) {
1020 	case NFS3_CREATE_UNCHECKED:
1021 	case NFS3_CREATE_GUARDED:
1022 		encode_sattr3(xdr, args->sattr, userns);
1023 		break;
1024 	case NFS3_CREATE_EXCLUSIVE:
1025 		encode_createverf3(xdr, args->verifier);
1026 		break;
1027 	default:
1028 		BUG();
1029 	}
1030 }
1031 
1032 static void nfs3_xdr_enc_create3args(struct rpc_rqst *req,
1033 				     struct xdr_stream *xdr,
1034 				     const void *data)
1035 {
1036 	const struct nfs3_createargs *args = data;
1037 
1038 	encode_diropargs3(xdr, args->fh, args->name, args->len);
1039 	encode_createhow3(xdr, args, rpc_rqst_userns(req));
1040 }
1041 
1042 /*
1043  * 3.3.9  MKDIR3args
1044  *
1045  *	struct MKDIR3args {
1046  *		diropargs3	where;
1047  *		sattr3		attributes;
1048  *	};
1049  */
1050 static void nfs3_xdr_enc_mkdir3args(struct rpc_rqst *req,
1051 				    struct xdr_stream *xdr,
1052 				    const void *data)
1053 {
1054 	const struct nfs3_mkdirargs *args = data;
1055 
1056 	encode_diropargs3(xdr, args->fh, args->name, args->len);
1057 	encode_sattr3(xdr, args->sattr, rpc_rqst_userns(req));
1058 }
1059 
1060 /*
1061  * 3.3.10  SYMLINK3args
1062  *
1063  *	struct symlinkdata3 {
1064  *		sattr3		symlink_attributes;
1065  *		nfspath3	symlink_data;
1066  *	};
1067  *
1068  *	struct SYMLINK3args {
1069  *		diropargs3	where;
1070  *		symlinkdata3	symlink;
1071  *	};
1072  */
1073 static void encode_symlinkdata3(struct xdr_stream *xdr,
1074 				const void *data,
1075 				struct user_namespace *userns)
1076 {
1077 	const struct nfs3_symlinkargs *args = data;
1078 
1079 	encode_sattr3(xdr, args->sattr, userns);
1080 	encode_nfspath3(xdr, args->pages, args->pathlen);
1081 }
1082 
1083 static void nfs3_xdr_enc_symlink3args(struct rpc_rqst *req,
1084 				      struct xdr_stream *xdr,
1085 				      const void *data)
1086 {
1087 	const struct nfs3_symlinkargs *args = data;
1088 
1089 	encode_diropargs3(xdr, args->fromfh, args->fromname, args->fromlen);
1090 	encode_symlinkdata3(xdr, args, rpc_rqst_userns(req));
1091 	xdr->buf->flags |= XDRBUF_WRITE;
1092 }
1093 
1094 /*
1095  * 3.3.11  MKNOD3args
1096  *
1097  *	struct devicedata3 {
1098  *		sattr3		dev_attributes;
1099  *		specdata3	spec;
1100  *	};
1101  *
1102  *	union mknoddata3 switch (ftype3 type) {
1103  *	case NF3CHR:
1104  *	case NF3BLK:
1105  *		devicedata3	device;
1106  *	case NF3SOCK:
1107  *	case NF3FIFO:
1108  *		sattr3		pipe_attributes;
1109  *	default:
1110  *		void;
1111  *	};
1112  *
1113  *	struct MKNOD3args {
1114  *		diropargs3	where;
1115  *		mknoddata3	what;
1116  *	};
1117  */
1118 static void encode_devicedata3(struct xdr_stream *xdr,
1119 			       const struct nfs3_mknodargs *args,
1120 			       struct user_namespace *userns)
1121 {
1122 	encode_sattr3(xdr, args->sattr, userns);
1123 	encode_specdata3(xdr, args->rdev);
1124 }
1125 
1126 static void encode_mknoddata3(struct xdr_stream *xdr,
1127 			      const struct nfs3_mknodargs *args,
1128 			      struct user_namespace *userns)
1129 {
1130 	encode_ftype3(xdr, args->type);
1131 	switch (args->type) {
1132 	case NF3CHR:
1133 	case NF3BLK:
1134 		encode_devicedata3(xdr, args, userns);
1135 		break;
1136 	case NF3SOCK:
1137 	case NF3FIFO:
1138 		encode_sattr3(xdr, args->sattr, userns);
1139 		break;
1140 	case NF3REG:
1141 	case NF3DIR:
1142 		break;
1143 	default:
1144 		BUG();
1145 	}
1146 }
1147 
1148 static void nfs3_xdr_enc_mknod3args(struct rpc_rqst *req,
1149 				    struct xdr_stream *xdr,
1150 				    const void *data)
1151 {
1152 	const struct nfs3_mknodargs *args = data;
1153 
1154 	encode_diropargs3(xdr, args->fh, args->name, args->len);
1155 	encode_mknoddata3(xdr, args, rpc_rqst_userns(req));
1156 }
1157 
1158 /*
1159  * 3.3.12  REMOVE3args
1160  *
1161  *	struct REMOVE3args {
1162  *		diropargs3  object;
1163  *	};
1164  */
1165 static void nfs3_xdr_enc_remove3args(struct rpc_rqst *req,
1166 				     struct xdr_stream *xdr,
1167 				     const void *data)
1168 {
1169 	const struct nfs_removeargs *args = data;
1170 
1171 	encode_diropargs3(xdr, args->fh, args->name.name, args->name.len);
1172 }
1173 
1174 /*
1175  * 3.3.14  RENAME3args
1176  *
1177  *	struct RENAME3args {
1178  *		diropargs3	from;
1179  *		diropargs3	to;
1180  *	};
1181  */
1182 static void nfs3_xdr_enc_rename3args(struct rpc_rqst *req,
1183 				     struct xdr_stream *xdr,
1184 				     const void *data)
1185 {
1186 	const struct nfs_renameargs *args = data;
1187 	const struct qstr *old = args->old_name;
1188 	const struct qstr *new = args->new_name;
1189 
1190 	encode_diropargs3(xdr, args->old_dir, old->name, old->len);
1191 	encode_diropargs3(xdr, args->new_dir, new->name, new->len);
1192 }
1193 
1194 /*
1195  * 3.3.15  LINK3args
1196  *
1197  *	struct LINK3args {
1198  *		nfs_fh3		file;
1199  *		diropargs3	link;
1200  *	};
1201  */
1202 static void nfs3_xdr_enc_link3args(struct rpc_rqst *req,
1203 				   struct xdr_stream *xdr,
1204 				   const void *data)
1205 {
1206 	const struct nfs3_linkargs *args = data;
1207 
1208 	encode_nfs_fh3(xdr, args->fromfh);
1209 	encode_diropargs3(xdr, args->tofh, args->toname, args->tolen);
1210 }
1211 
1212 /*
1213  * 3.3.16  READDIR3args
1214  *
1215  *	struct READDIR3args {
1216  *		nfs_fh3		dir;
1217  *		cookie3		cookie;
1218  *		cookieverf3	cookieverf;
1219  *		count3		count;
1220  *	};
1221  */
1222 static void encode_readdir3args(struct xdr_stream *xdr,
1223 				const struct nfs3_readdirargs *args)
1224 {
1225 	__be32 *p;
1226 
1227 	encode_nfs_fh3(xdr, args->fh);
1228 
1229 	p = xdr_reserve_space(xdr, 8 + NFS3_COOKIEVERFSIZE + 4);
1230 	p = xdr_encode_cookie3(p, args->cookie);
1231 	p = xdr_encode_cookieverf3(p, args->verf);
1232 	*p = cpu_to_be32(args->count);
1233 }
1234 
1235 static void nfs3_xdr_enc_readdir3args(struct rpc_rqst *req,
1236 				      struct xdr_stream *xdr,
1237 				      const void *data)
1238 {
1239 	const struct nfs3_readdirargs *args = data;
1240 
1241 	encode_readdir3args(xdr, args);
1242 	rpc_prepare_reply_pages(req, args->pages, 0,
1243 				args->count, NFS3_readdirres_sz);
1244 }
1245 
1246 /*
1247  * 3.3.17  READDIRPLUS3args
1248  *
1249  *	struct READDIRPLUS3args {
1250  *		nfs_fh3		dir;
1251  *		cookie3		cookie;
1252  *		cookieverf3	cookieverf;
1253  *		count3		dircount;
1254  *		count3		maxcount;
1255  *	};
1256  */
1257 static void encode_readdirplus3args(struct xdr_stream *xdr,
1258 				    const struct nfs3_readdirargs *args)
1259 {
1260 	__be32 *p;
1261 
1262 	encode_nfs_fh3(xdr, args->fh);
1263 
1264 	p = xdr_reserve_space(xdr, 8 + NFS3_COOKIEVERFSIZE + 4 + 4);
1265 	p = xdr_encode_cookie3(p, args->cookie);
1266 	p = xdr_encode_cookieverf3(p, args->verf);
1267 
1268 	/*
1269 	 * readdirplus: need dircount + buffer size.
1270 	 * We just make sure we make dircount big enough
1271 	 */
1272 	*p++ = cpu_to_be32(args->count >> 3);
1273 
1274 	*p = cpu_to_be32(args->count);
1275 }
1276 
1277 static void nfs3_xdr_enc_readdirplus3args(struct rpc_rqst *req,
1278 					  struct xdr_stream *xdr,
1279 					  const void *data)
1280 {
1281 	const struct nfs3_readdirargs *args = data;
1282 
1283 	encode_readdirplus3args(xdr, args);
1284 	rpc_prepare_reply_pages(req, args->pages, 0,
1285 				args->count, NFS3_readdirres_sz);
1286 }
1287 
1288 /*
1289  * 3.3.21  COMMIT3args
1290  *
1291  *	struct COMMIT3args {
1292  *		nfs_fh3		file;
1293  *		offset3		offset;
1294  *		count3		count;
1295  *	};
1296  */
1297 static void encode_commit3args(struct xdr_stream *xdr,
1298 			       const struct nfs_commitargs *args)
1299 {
1300 	__be32 *p;
1301 
1302 	encode_nfs_fh3(xdr, args->fh);
1303 
1304 	p = xdr_reserve_space(xdr, 8 + 4);
1305 	p = xdr_encode_hyper(p, args->offset);
1306 	*p = cpu_to_be32(args->count);
1307 }
1308 
1309 static void nfs3_xdr_enc_commit3args(struct rpc_rqst *req,
1310 				     struct xdr_stream *xdr,
1311 				     const void *data)
1312 {
1313 	const struct nfs_commitargs *args = data;
1314 
1315 	encode_commit3args(xdr, args);
1316 }
1317 
1318 #ifdef CONFIG_NFS_V3_ACL
1319 
1320 static void nfs3_xdr_enc_getacl3args(struct rpc_rqst *req,
1321 				     struct xdr_stream *xdr,
1322 				     const void *data)
1323 {
1324 	const struct nfs3_getaclargs *args = data;
1325 
1326 	encode_nfs_fh3(xdr, args->fh);
1327 	encode_uint32(xdr, args->mask);
1328 	if (args->mask & (NFS_ACL | NFS_DFACL)) {
1329 		rpc_prepare_reply_pages(req, args->pages, 0,
1330 					NFSACL_MAXPAGES << PAGE_SHIFT,
1331 					ACL3_getaclres_sz);
1332 		req->rq_rcv_buf.flags |= XDRBUF_SPARSE_PAGES;
1333 	}
1334 }
1335 
1336 static void nfs3_xdr_enc_setacl3args(struct rpc_rqst *req,
1337 				     struct xdr_stream *xdr,
1338 				     const void *data)
1339 {
1340 	const struct nfs3_setaclargs *args = data;
1341 	unsigned int base;
1342 	int error;
1343 
1344 	encode_nfs_fh3(xdr, NFS_FH(args->inode));
1345 	encode_uint32(xdr, args->mask);
1346 
1347 	base = req->rq_slen;
1348 	if (args->npages != 0)
1349 		xdr_write_pages(xdr, args->pages, 0, args->len);
1350 	else
1351 		xdr_reserve_space(xdr, args->len);
1352 
1353 	error = nfsacl_encode(xdr->buf, base, args->inode,
1354 			    (args->mask & NFS_ACL) ?
1355 			    args->acl_access : NULL, 1, 0);
1356 	/* FIXME: this is just broken */
1357 	BUG_ON(error < 0);
1358 	error = nfsacl_encode(xdr->buf, base + error, args->inode,
1359 			    (args->mask & NFS_DFACL) ?
1360 			    args->acl_default : NULL, 1,
1361 			    NFS_ACL_DEFAULT);
1362 	BUG_ON(error < 0);
1363 }
1364 
1365 #endif  /* CONFIG_NFS_V3_ACL */
1366 
1367 /*
1368  * NFSv3 XDR decode functions
1369  *
1370  * NFSv3 result types are defined in section 3.3 of RFC 1813:
1371  * "NFS Version 3 Protocol Specification".
1372  */
1373 
1374 /*
1375  * 3.3.1  GETATTR3res
1376  *
1377  *	struct GETATTR3resok {
1378  *		fattr3		obj_attributes;
1379  *	};
1380  *
1381  *	union GETATTR3res switch (nfsstat3 status) {
1382  *	case NFS3_OK:
1383  *		GETATTR3resok  resok;
1384  *	default:
1385  *		void;
1386  *	};
1387  */
1388 static int nfs3_xdr_dec_getattr3res(struct rpc_rqst *req,
1389 				    struct xdr_stream *xdr,
1390 				    void *result)
1391 {
1392 	enum nfs_stat status;
1393 	int error;
1394 
1395 	error = decode_nfsstat3(xdr, &status);
1396 	if (unlikely(error))
1397 		goto out;
1398 	if (status != NFS3_OK)
1399 		goto out_default;
1400 	error = decode_fattr3(xdr, result, rpc_rqst_userns(req));
1401 out:
1402 	return error;
1403 out_default:
1404 	return nfs3_stat_to_errno(status);
1405 }
1406 
1407 /*
1408  * 3.3.2  SETATTR3res
1409  *
1410  *	struct SETATTR3resok {
1411  *		wcc_data  obj_wcc;
1412  *	};
1413  *
1414  *	struct SETATTR3resfail {
1415  *		wcc_data  obj_wcc;
1416  *	};
1417  *
1418  *	union SETATTR3res switch (nfsstat3 status) {
1419  *	case NFS3_OK:
1420  *		SETATTR3resok   resok;
1421  *	default:
1422  *		SETATTR3resfail resfail;
1423  *	};
1424  */
1425 static int nfs3_xdr_dec_setattr3res(struct rpc_rqst *req,
1426 				    struct xdr_stream *xdr,
1427 				    void *result)
1428 {
1429 	enum nfs_stat status;
1430 	int error;
1431 
1432 	error = decode_nfsstat3(xdr, &status);
1433 	if (unlikely(error))
1434 		goto out;
1435 	error = decode_wcc_data(xdr, result, rpc_rqst_userns(req));
1436 	if (unlikely(error))
1437 		goto out;
1438 	if (status != NFS3_OK)
1439 		goto out_status;
1440 out:
1441 	return error;
1442 out_status:
1443 	return nfs3_stat_to_errno(status);
1444 }
1445 
1446 /*
1447  * 3.3.3  LOOKUP3res
1448  *
1449  *	struct LOOKUP3resok {
1450  *		nfs_fh3		object;
1451  *		post_op_attr	obj_attributes;
1452  *		post_op_attr	dir_attributes;
1453  *	};
1454  *
1455  *	struct LOOKUP3resfail {
1456  *		post_op_attr	dir_attributes;
1457  *	};
1458  *
1459  *	union LOOKUP3res switch (nfsstat3 status) {
1460  *	case NFS3_OK:
1461  *		LOOKUP3resok	resok;
1462  *	default:
1463  *		LOOKUP3resfail	resfail;
1464  *	};
1465  */
1466 static int nfs3_xdr_dec_lookup3res(struct rpc_rqst *req,
1467 				   struct xdr_stream *xdr,
1468 				   void *data)
1469 {
1470 	struct user_namespace *userns = rpc_rqst_userns(req);
1471 	struct nfs3_diropres *result = data;
1472 	enum nfs_stat status;
1473 	int error;
1474 
1475 	error = decode_nfsstat3(xdr, &status);
1476 	if (unlikely(error))
1477 		goto out;
1478 	if (status != NFS3_OK)
1479 		goto out_default;
1480 	error = decode_nfs_fh3(xdr, result->fh);
1481 	if (unlikely(error))
1482 		goto out;
1483 	error = decode_post_op_attr(xdr, result->fattr, userns);
1484 	if (unlikely(error))
1485 		goto out;
1486 	error = decode_post_op_attr(xdr, result->dir_attr, userns);
1487 out:
1488 	return error;
1489 out_default:
1490 	error = decode_post_op_attr(xdr, result->dir_attr, userns);
1491 	if (unlikely(error))
1492 		goto out;
1493 	return nfs3_stat_to_errno(status);
1494 }
1495 
1496 /*
1497  * 3.3.4  ACCESS3res
1498  *
1499  *	struct ACCESS3resok {
1500  *		post_op_attr	obj_attributes;
1501  *		uint32		access;
1502  *	};
1503  *
1504  *	struct ACCESS3resfail {
1505  *		post_op_attr	obj_attributes;
1506  *	};
1507  *
1508  *	union ACCESS3res switch (nfsstat3 status) {
1509  *	case NFS3_OK:
1510  *		ACCESS3resok	resok;
1511  *	default:
1512  *		ACCESS3resfail	resfail;
1513  *	};
1514  */
1515 static int nfs3_xdr_dec_access3res(struct rpc_rqst *req,
1516 				   struct xdr_stream *xdr,
1517 				   void *data)
1518 {
1519 	struct nfs3_accessres *result = data;
1520 	enum nfs_stat status;
1521 	int error;
1522 
1523 	error = decode_nfsstat3(xdr, &status);
1524 	if (unlikely(error))
1525 		goto out;
1526 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
1527 	if (unlikely(error))
1528 		goto out;
1529 	if (status != NFS3_OK)
1530 		goto out_default;
1531 	error = decode_uint32(xdr, &result->access);
1532 out:
1533 	return error;
1534 out_default:
1535 	return nfs3_stat_to_errno(status);
1536 }
1537 
1538 /*
1539  * 3.3.5  READLINK3res
1540  *
1541  *	struct READLINK3resok {
1542  *		post_op_attr	symlink_attributes;
1543  *		nfspath3	data;
1544  *	};
1545  *
1546  *	struct READLINK3resfail {
1547  *		post_op_attr	symlink_attributes;
1548  *	};
1549  *
1550  *	union READLINK3res switch (nfsstat3 status) {
1551  *	case NFS3_OK:
1552  *		READLINK3resok	resok;
1553  *	default:
1554  *		READLINK3resfail resfail;
1555  *	};
1556  */
1557 static int nfs3_xdr_dec_readlink3res(struct rpc_rqst *req,
1558 				     struct xdr_stream *xdr,
1559 				     void *result)
1560 {
1561 	enum nfs_stat status;
1562 	int error;
1563 
1564 	error = decode_nfsstat3(xdr, &status);
1565 	if (unlikely(error))
1566 		goto out;
1567 	error = decode_post_op_attr(xdr, result, rpc_rqst_userns(req));
1568 	if (unlikely(error))
1569 		goto out;
1570 	if (status != NFS3_OK)
1571 		goto out_default;
1572 	error = decode_nfspath3(xdr);
1573 out:
1574 	return error;
1575 out_default:
1576 	return nfs3_stat_to_errno(status);
1577 }
1578 
1579 /*
1580  * 3.3.6  READ3res
1581  *
1582  *	struct READ3resok {
1583  *		post_op_attr	file_attributes;
1584  *		count3		count;
1585  *		bool		eof;
1586  *		opaque		data<>;
1587  *	};
1588  *
1589  *	struct READ3resfail {
1590  *		post_op_attr	file_attributes;
1591  *	};
1592  *
1593  *	union READ3res switch (nfsstat3 status) {
1594  *	case NFS3_OK:
1595  *		READ3resok	resok;
1596  *	default:
1597  *		READ3resfail	resfail;
1598  *	};
1599  */
1600 static int decode_read3resok(struct xdr_stream *xdr,
1601 			     struct nfs_pgio_res *result)
1602 {
1603 	u32 eof, count, ocount, recvd;
1604 	__be32 *p;
1605 
1606 	p = xdr_inline_decode(xdr, 4 + 4 + 4);
1607 	if (unlikely(!p))
1608 		return -EIO;
1609 	count = be32_to_cpup(p++);
1610 	eof = be32_to_cpup(p++);
1611 	ocount = be32_to_cpup(p++);
1612 	if (unlikely(ocount != count))
1613 		goto out_mismatch;
1614 	recvd = xdr_read_pages(xdr, count);
1615 	if (unlikely(count > recvd))
1616 		goto out_cheating;
1617 out:
1618 	result->eof = eof;
1619 	result->count = count;
1620 	return count;
1621 out_mismatch:
1622 	dprintk("NFS: READ count doesn't match length of opaque: "
1623 		"count %u != ocount %u\n", count, ocount);
1624 	return -EIO;
1625 out_cheating:
1626 	dprintk("NFS: server cheating in read result: "
1627 		"count %u > recvd %u\n", count, recvd);
1628 	count = recvd;
1629 	eof = 0;
1630 	goto out;
1631 }
1632 
1633 static int nfs3_xdr_dec_read3res(struct rpc_rqst *req, struct xdr_stream *xdr,
1634 				 void *data)
1635 {
1636 	struct nfs_pgio_res *result = data;
1637 	unsigned int pos;
1638 	enum nfs_stat status;
1639 	int error;
1640 
1641 	pos = xdr_stream_pos(xdr);
1642 	error = decode_nfsstat3(xdr, &status);
1643 	if (unlikely(error))
1644 		goto out;
1645 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
1646 	if (unlikely(error))
1647 		goto out;
1648 	result->op_status = status;
1649 	if (status != NFS3_OK)
1650 		goto out_status;
1651 	result->replen = 4 + ((xdr_stream_pos(xdr) - pos) >> 2);
1652 	error = decode_read3resok(xdr, result);
1653 out:
1654 	return error;
1655 out_status:
1656 	return nfs3_stat_to_errno(status);
1657 }
1658 
1659 /*
1660  * 3.3.7  WRITE3res
1661  *
1662  *	enum stable_how {
1663  *		UNSTABLE  = 0,
1664  *		DATA_SYNC = 1,
1665  *		FILE_SYNC = 2
1666  *	};
1667  *
1668  *	struct WRITE3resok {
1669  *		wcc_data	file_wcc;
1670  *		count3		count;
1671  *		stable_how	committed;
1672  *		writeverf3	verf;
1673  *	};
1674  *
1675  *	struct WRITE3resfail {
1676  *		wcc_data	file_wcc;
1677  *	};
1678  *
1679  *	union WRITE3res switch (nfsstat3 status) {
1680  *	case NFS3_OK:
1681  *		WRITE3resok	resok;
1682  *	default:
1683  *		WRITE3resfail	resfail;
1684  *	};
1685  */
1686 static int decode_write3resok(struct xdr_stream *xdr,
1687 			      struct nfs_pgio_res *result)
1688 {
1689 	__be32 *p;
1690 
1691 	p = xdr_inline_decode(xdr, 4 + 4);
1692 	if (unlikely(!p))
1693 		return -EIO;
1694 	result->count = be32_to_cpup(p++);
1695 	result->verf->committed = be32_to_cpup(p++);
1696 	if (unlikely(result->verf->committed > NFS_FILE_SYNC))
1697 		goto out_badvalue;
1698 	if (decode_writeverf3(xdr, &result->verf->verifier))
1699 		return -EIO;
1700 	return result->count;
1701 out_badvalue:
1702 	dprintk("NFS: bad stable_how value: %u\n", result->verf->committed);
1703 	return -EIO;
1704 }
1705 
1706 static int nfs3_xdr_dec_write3res(struct rpc_rqst *req, struct xdr_stream *xdr,
1707 				  void *data)
1708 {
1709 	struct nfs_pgio_res *result = data;
1710 	enum nfs_stat status;
1711 	int error;
1712 
1713 	error = decode_nfsstat3(xdr, &status);
1714 	if (unlikely(error))
1715 		goto out;
1716 	error = decode_wcc_data(xdr, result->fattr, rpc_rqst_userns(req));
1717 	if (unlikely(error))
1718 		goto out;
1719 	result->op_status = status;
1720 	if (status != NFS3_OK)
1721 		goto out_status;
1722 	error = decode_write3resok(xdr, result);
1723 out:
1724 	return error;
1725 out_status:
1726 	return nfs3_stat_to_errno(status);
1727 }
1728 
1729 /*
1730  * 3.3.8  CREATE3res
1731  *
1732  *	struct CREATE3resok {
1733  *		post_op_fh3	obj;
1734  *		post_op_attr	obj_attributes;
1735  *		wcc_data	dir_wcc;
1736  *	};
1737  *
1738  *	struct CREATE3resfail {
1739  *		wcc_data	dir_wcc;
1740  *	};
1741  *
1742  *	union CREATE3res switch (nfsstat3 status) {
1743  *	case NFS3_OK:
1744  *		CREATE3resok	resok;
1745  *	default:
1746  *		CREATE3resfail	resfail;
1747  *	};
1748  */
1749 static int decode_create3resok(struct xdr_stream *xdr,
1750 			       struct nfs3_diropres *result,
1751 			       struct user_namespace *userns)
1752 {
1753 	int error;
1754 
1755 	error = decode_post_op_fh3(xdr, result->fh);
1756 	if (unlikely(error))
1757 		goto out;
1758 	error = decode_post_op_attr(xdr, result->fattr, userns);
1759 	if (unlikely(error))
1760 		goto out;
1761 	/* The server isn't required to return a file handle.
1762 	 * If it didn't, force the client to perform a LOOKUP
1763 	 * to determine the correct file handle and attribute
1764 	 * values for the new object. */
1765 	if (result->fh->size == 0)
1766 		result->fattr->valid = 0;
1767 	error = decode_wcc_data(xdr, result->dir_attr, userns);
1768 out:
1769 	return error;
1770 }
1771 
1772 static int nfs3_xdr_dec_create3res(struct rpc_rqst *req,
1773 				   struct xdr_stream *xdr,
1774 				   void *data)
1775 {
1776 	struct user_namespace *userns = rpc_rqst_userns(req);
1777 	struct nfs3_diropres *result = data;
1778 	enum nfs_stat status;
1779 	int error;
1780 
1781 	error = decode_nfsstat3(xdr, &status);
1782 	if (unlikely(error))
1783 		goto out;
1784 	if (status != NFS3_OK)
1785 		goto out_default;
1786 	error = decode_create3resok(xdr, result, userns);
1787 out:
1788 	return error;
1789 out_default:
1790 	error = decode_wcc_data(xdr, result->dir_attr, userns);
1791 	if (unlikely(error))
1792 		goto out;
1793 	return nfs3_stat_to_errno(status);
1794 }
1795 
1796 /*
1797  * 3.3.12  REMOVE3res
1798  *
1799  *	struct REMOVE3resok {
1800  *		wcc_data    dir_wcc;
1801  *	};
1802  *
1803  *	struct REMOVE3resfail {
1804  *		wcc_data    dir_wcc;
1805  *	};
1806  *
1807  *	union REMOVE3res switch (nfsstat3 status) {
1808  *	case NFS3_OK:
1809  *		REMOVE3resok   resok;
1810  *	default:
1811  *		REMOVE3resfail resfail;
1812  *	};
1813  */
1814 static int nfs3_xdr_dec_remove3res(struct rpc_rqst *req,
1815 				   struct xdr_stream *xdr,
1816 				   void *data)
1817 {
1818 	struct nfs_removeres *result = data;
1819 	enum nfs_stat status;
1820 	int error;
1821 
1822 	error = decode_nfsstat3(xdr, &status);
1823 	if (unlikely(error))
1824 		goto out;
1825 	error = decode_wcc_data(xdr, result->dir_attr, rpc_rqst_userns(req));
1826 	if (unlikely(error))
1827 		goto out;
1828 	if (status != NFS3_OK)
1829 		goto out_status;
1830 out:
1831 	return error;
1832 out_status:
1833 	return nfs3_stat_to_errno(status);
1834 }
1835 
1836 /*
1837  * 3.3.14  RENAME3res
1838  *
1839  *	struct RENAME3resok {
1840  *		wcc_data	fromdir_wcc;
1841  *		wcc_data	todir_wcc;
1842  *	};
1843  *
1844  *	struct RENAME3resfail {
1845  *		wcc_data	fromdir_wcc;
1846  *		wcc_data	todir_wcc;
1847  *	};
1848  *
1849  *	union RENAME3res switch (nfsstat3 status) {
1850  *	case NFS3_OK:
1851  *		RENAME3resok   resok;
1852  *	default:
1853  *		RENAME3resfail resfail;
1854  *	};
1855  */
1856 static int nfs3_xdr_dec_rename3res(struct rpc_rqst *req,
1857 				   struct xdr_stream *xdr,
1858 				   void *data)
1859 {
1860 	struct user_namespace *userns = rpc_rqst_userns(req);
1861 	struct nfs_renameres *result = data;
1862 	enum nfs_stat status;
1863 	int error;
1864 
1865 	error = decode_nfsstat3(xdr, &status);
1866 	if (unlikely(error))
1867 		goto out;
1868 	error = decode_wcc_data(xdr, result->old_fattr, userns);
1869 	if (unlikely(error))
1870 		goto out;
1871 	error = decode_wcc_data(xdr, result->new_fattr, userns);
1872 	if (unlikely(error))
1873 		goto out;
1874 	if (status != NFS3_OK)
1875 		goto out_status;
1876 out:
1877 	return error;
1878 out_status:
1879 	return nfs3_stat_to_errno(status);
1880 }
1881 
1882 /*
1883  * 3.3.15  LINK3res
1884  *
1885  *	struct LINK3resok {
1886  *		post_op_attr	file_attributes;
1887  *		wcc_data	linkdir_wcc;
1888  *	};
1889  *
1890  *	struct LINK3resfail {
1891  *		post_op_attr	file_attributes;
1892  *		wcc_data	linkdir_wcc;
1893  *	};
1894  *
1895  *	union LINK3res switch (nfsstat3 status) {
1896  *	case NFS3_OK:
1897  *		LINK3resok	resok;
1898  *	default:
1899  *		LINK3resfail	resfail;
1900  *	};
1901  */
1902 static int nfs3_xdr_dec_link3res(struct rpc_rqst *req, struct xdr_stream *xdr,
1903 				 void *data)
1904 {
1905 	struct user_namespace *userns = rpc_rqst_userns(req);
1906 	struct nfs3_linkres *result = data;
1907 	enum nfs_stat status;
1908 	int error;
1909 
1910 	error = decode_nfsstat3(xdr, &status);
1911 	if (unlikely(error))
1912 		goto out;
1913 	error = decode_post_op_attr(xdr, result->fattr, userns);
1914 	if (unlikely(error))
1915 		goto out;
1916 	error = decode_wcc_data(xdr, result->dir_attr, userns);
1917 	if (unlikely(error))
1918 		goto out;
1919 	if (status != NFS3_OK)
1920 		goto out_status;
1921 out:
1922 	return error;
1923 out_status:
1924 	return nfs3_stat_to_errno(status);
1925 }
1926 
1927 /**
1928  * nfs3_decode_dirent - Decode a single NFSv3 directory entry stored in
1929  *			the local page cache
1930  * @xdr: XDR stream where entry resides
1931  * @entry: buffer to fill in with entry data
1932  * @plus: boolean indicating whether this should be a readdirplus entry
1933  *
1934  * Returns zero if successful, otherwise a negative errno value is
1935  * returned.
1936  *
1937  * This function is not invoked during READDIR reply decoding, but
1938  * rather whenever an application invokes the getdents(2) system call
1939  * on a directory already in our cache.
1940  *
1941  * 3.3.16  entry3
1942  *
1943  *	struct entry3 {
1944  *		fileid3		fileid;
1945  *		filename3	name;
1946  *		cookie3		cookie;
1947  *		fhandle3	filehandle;
1948  *		post_op_attr3	attributes;
1949  *		entry3		*nextentry;
1950  *	};
1951  *
1952  * 3.3.17  entryplus3
1953  *	struct entryplus3 {
1954  *		fileid3		fileid;
1955  *		filename3	name;
1956  *		cookie3		cookie;
1957  *		post_op_attr	name_attributes;
1958  *		post_op_fh3	name_handle;
1959  *		entryplus3	*nextentry;
1960  *	};
1961  */
1962 int nfs3_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry,
1963 		       bool plus)
1964 {
1965 	struct user_namespace *userns = rpc_userns(entry->server->client);
1966 	struct nfs_entry old = *entry;
1967 	__be32 *p;
1968 	int error;
1969 	u64 new_cookie;
1970 
1971 	p = xdr_inline_decode(xdr, 4);
1972 	if (unlikely(!p))
1973 		return -EAGAIN;
1974 	if (*p == xdr_zero) {
1975 		p = xdr_inline_decode(xdr, 4);
1976 		if (unlikely(!p))
1977 			return -EAGAIN;
1978 		if (*p == xdr_zero)
1979 			return -EAGAIN;
1980 		entry->eof = 1;
1981 		return -EBADCOOKIE;
1982 	}
1983 
1984 	error = decode_fileid3(xdr, &entry->ino);
1985 	if (unlikely(error))
1986 		return error;
1987 
1988 	error = decode_inline_filename3(xdr, &entry->name, &entry->len);
1989 	if (unlikely(error))
1990 		return error;
1991 
1992 	error = decode_cookie3(xdr, &new_cookie);
1993 	if (unlikely(error))
1994 		return error;
1995 
1996 	entry->d_type = DT_UNKNOWN;
1997 
1998 	if (plus) {
1999 		entry->fattr->valid = 0;
2000 		error = decode_post_op_attr(xdr, entry->fattr, userns);
2001 		if (unlikely(error))
2002 			return error;
2003 		if (entry->fattr->valid & NFS_ATTR_FATTR_V3)
2004 			entry->d_type = nfs_umode_to_dtype(entry->fattr->mode);
2005 
2006 		if (entry->fattr->fileid != entry->ino) {
2007 			entry->fattr->mounted_on_fileid = entry->ino;
2008 			entry->fattr->valid |= NFS_ATTR_FATTR_MOUNTED_ON_FILEID;
2009 		}
2010 
2011 		/* In fact, a post_op_fh3: */
2012 		p = xdr_inline_decode(xdr, 4);
2013 		if (unlikely(!p))
2014 			return -EAGAIN;
2015 		if (*p != xdr_zero) {
2016 			error = decode_nfs_fh3(xdr, entry->fh);
2017 			if (unlikely(error)) {
2018 				if (error == -E2BIG)
2019 					goto out_truncated;
2020 				return error;
2021 			}
2022 		} else
2023 			zero_nfs_fh3(entry->fh);
2024 	}
2025 
2026 	entry->prev_cookie = entry->cookie;
2027 	entry->cookie = new_cookie;
2028 
2029 	return 0;
2030 
2031 out_truncated:
2032 	dprintk("NFS: directory entry contains invalid file handle\n");
2033 	*entry = old;
2034 	return -EAGAIN;
2035 }
2036 
2037 /*
2038  * 3.3.16  READDIR3res
2039  *
2040  *	struct dirlist3 {
2041  *		entry3		*entries;
2042  *		bool		eof;
2043  *	};
2044  *
2045  *	struct READDIR3resok {
2046  *		post_op_attr	dir_attributes;
2047  *		cookieverf3	cookieverf;
2048  *		dirlist3	reply;
2049  *	};
2050  *
2051  *	struct READDIR3resfail {
2052  *		post_op_attr	dir_attributes;
2053  *	};
2054  *
2055  *	union READDIR3res switch (nfsstat3 status) {
2056  *	case NFS3_OK:
2057  *		READDIR3resok	resok;
2058  *	default:
2059  *		READDIR3resfail	resfail;
2060  *	};
2061  *
2062  * Read the directory contents into the page cache, but otherwise
2063  * don't touch them.  The actual decoding is done by nfs3_decode_entry()
2064  * during subsequent nfs_readdir() calls.
2065  */
2066 static int decode_dirlist3(struct xdr_stream *xdr)
2067 {
2068 	return xdr_read_pages(xdr, xdr->buf->page_len);
2069 }
2070 
2071 static int decode_readdir3resok(struct xdr_stream *xdr,
2072 				struct nfs3_readdirres *result,
2073 				struct user_namespace *userns)
2074 {
2075 	int error;
2076 
2077 	error = decode_post_op_attr(xdr, result->dir_attr, userns);
2078 	if (unlikely(error))
2079 		goto out;
2080 	/* XXX: do we need to check if result->verf != NULL ? */
2081 	error = decode_cookieverf3(xdr, result->verf);
2082 	if (unlikely(error))
2083 		goto out;
2084 	error = decode_dirlist3(xdr);
2085 out:
2086 	return error;
2087 }
2088 
2089 static int nfs3_xdr_dec_readdir3res(struct rpc_rqst *req,
2090 				    struct xdr_stream *xdr,
2091 				    void *data)
2092 {
2093 	struct nfs3_readdirres *result = data;
2094 	enum nfs_stat status;
2095 	int error;
2096 
2097 	error = decode_nfsstat3(xdr, &status);
2098 	if (unlikely(error))
2099 		goto out;
2100 	if (status != NFS3_OK)
2101 		goto out_default;
2102 	error = decode_readdir3resok(xdr, result, rpc_rqst_userns(req));
2103 out:
2104 	return error;
2105 out_default:
2106 	error = decode_post_op_attr(xdr, result->dir_attr, rpc_rqst_userns(req));
2107 	if (unlikely(error))
2108 		goto out;
2109 	return nfs3_stat_to_errno(status);
2110 }
2111 
2112 /*
2113  * 3.3.18  FSSTAT3res
2114  *
2115  *	struct FSSTAT3resok {
2116  *		post_op_attr	obj_attributes;
2117  *		size3		tbytes;
2118  *		size3		fbytes;
2119  *		size3		abytes;
2120  *		size3		tfiles;
2121  *		size3		ffiles;
2122  *		size3		afiles;
2123  *		uint32		invarsec;
2124  *	};
2125  *
2126  *	struct FSSTAT3resfail {
2127  *		post_op_attr	obj_attributes;
2128  *	};
2129  *
2130  *	union FSSTAT3res switch (nfsstat3 status) {
2131  *	case NFS3_OK:
2132  *		FSSTAT3resok	resok;
2133  *	default:
2134  *		FSSTAT3resfail	resfail;
2135  *	};
2136  */
2137 static int decode_fsstat3resok(struct xdr_stream *xdr,
2138 			       struct nfs_fsstat *result)
2139 {
2140 	__be32 *p;
2141 
2142 	p = xdr_inline_decode(xdr, 8 * 6 + 4);
2143 	if (unlikely(!p))
2144 		return -EIO;
2145 	p = xdr_decode_size3(p, &result->tbytes);
2146 	p = xdr_decode_size3(p, &result->fbytes);
2147 	p = xdr_decode_size3(p, &result->abytes);
2148 	p = xdr_decode_size3(p, &result->tfiles);
2149 	p = xdr_decode_size3(p, &result->ffiles);
2150 	xdr_decode_size3(p, &result->afiles);
2151 	/* ignore invarsec */
2152 	return 0;
2153 }
2154 
2155 static int nfs3_xdr_dec_fsstat3res(struct rpc_rqst *req,
2156 				   struct xdr_stream *xdr,
2157 				   void *data)
2158 {
2159 	struct nfs_fsstat *result = data;
2160 	enum nfs_stat status;
2161 	int error;
2162 
2163 	error = decode_nfsstat3(xdr, &status);
2164 	if (unlikely(error))
2165 		goto out;
2166 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
2167 	if (unlikely(error))
2168 		goto out;
2169 	if (status != NFS3_OK)
2170 		goto out_status;
2171 	error = decode_fsstat3resok(xdr, result);
2172 out:
2173 	return error;
2174 out_status:
2175 	return nfs3_stat_to_errno(status);
2176 }
2177 
2178 /*
2179  * 3.3.19  FSINFO3res
2180  *
2181  *	struct FSINFO3resok {
2182  *		post_op_attr	obj_attributes;
2183  *		uint32		rtmax;
2184  *		uint32		rtpref;
2185  *		uint32		rtmult;
2186  *		uint32		wtmax;
2187  *		uint32		wtpref;
2188  *		uint32		wtmult;
2189  *		uint32		dtpref;
2190  *		size3		maxfilesize;
2191  *		nfstime3	time_delta;
2192  *		uint32		properties;
2193  *	};
2194  *
2195  *	struct FSINFO3resfail {
2196  *		post_op_attr	obj_attributes;
2197  *	};
2198  *
2199  *	union FSINFO3res switch (nfsstat3 status) {
2200  *	case NFS3_OK:
2201  *		FSINFO3resok	resok;
2202  *	default:
2203  *		FSINFO3resfail	resfail;
2204  *	};
2205  */
2206 static int decode_fsinfo3resok(struct xdr_stream *xdr,
2207 			       struct nfs_fsinfo *result)
2208 {
2209 	__be32 *p;
2210 
2211 	p = xdr_inline_decode(xdr, 4 * 7 + 8 + 8 + 4);
2212 	if (unlikely(!p))
2213 		return -EIO;
2214 	result->rtmax  = be32_to_cpup(p++);
2215 	result->rtpref = be32_to_cpup(p++);
2216 	result->rtmult = be32_to_cpup(p++);
2217 	result->wtmax  = be32_to_cpup(p++);
2218 	result->wtpref = be32_to_cpup(p++);
2219 	result->wtmult = be32_to_cpup(p++);
2220 	result->dtpref = be32_to_cpup(p++);
2221 	p = xdr_decode_size3(p, &result->maxfilesize);
2222 	xdr_decode_nfstime3(p, &result->time_delta);
2223 
2224 	/* ignore properties */
2225 	result->lease_time = 0;
2226 	return 0;
2227 }
2228 
2229 static int nfs3_xdr_dec_fsinfo3res(struct rpc_rqst *req,
2230 				   struct xdr_stream *xdr,
2231 				   void *data)
2232 {
2233 	struct nfs_fsinfo *result = data;
2234 	enum nfs_stat status;
2235 	int error;
2236 
2237 	error = decode_nfsstat3(xdr, &status);
2238 	if (unlikely(error))
2239 		goto out;
2240 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
2241 	if (unlikely(error))
2242 		goto out;
2243 	if (status != NFS3_OK)
2244 		goto out_status;
2245 	error = decode_fsinfo3resok(xdr, result);
2246 out:
2247 	return error;
2248 out_status:
2249 	return nfs3_stat_to_errno(status);
2250 }
2251 
2252 /*
2253  * 3.3.20  PATHCONF3res
2254  *
2255  *	struct PATHCONF3resok {
2256  *		post_op_attr	obj_attributes;
2257  *		uint32		linkmax;
2258  *		uint32		name_max;
2259  *		bool		no_trunc;
2260  *		bool		chown_restricted;
2261  *		bool		case_insensitive;
2262  *		bool		case_preserving;
2263  *	};
2264  *
2265  *	struct PATHCONF3resfail {
2266  *		post_op_attr	obj_attributes;
2267  *	};
2268  *
2269  *	union PATHCONF3res switch (nfsstat3 status) {
2270  *	case NFS3_OK:
2271  *		PATHCONF3resok	resok;
2272  *	default:
2273  *		PATHCONF3resfail resfail;
2274  *	};
2275  */
2276 static int decode_pathconf3resok(struct xdr_stream *xdr,
2277 				 struct nfs_pathconf *result)
2278 {
2279 	__be32 *p;
2280 
2281 	p = xdr_inline_decode(xdr, 4 * 6);
2282 	if (unlikely(!p))
2283 		return -EIO;
2284 	result->max_link = be32_to_cpup(p++);
2285 	result->max_namelen = be32_to_cpup(p);
2286 	/* ignore remaining fields */
2287 	return 0;
2288 }
2289 
2290 static int nfs3_xdr_dec_pathconf3res(struct rpc_rqst *req,
2291 				     struct xdr_stream *xdr,
2292 				     void *data)
2293 {
2294 	struct nfs_pathconf *result = data;
2295 	enum nfs_stat status;
2296 	int error;
2297 
2298 	error = decode_nfsstat3(xdr, &status);
2299 	if (unlikely(error))
2300 		goto out;
2301 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
2302 	if (unlikely(error))
2303 		goto out;
2304 	if (status != NFS3_OK)
2305 		goto out_status;
2306 	error = decode_pathconf3resok(xdr, result);
2307 out:
2308 	return error;
2309 out_status:
2310 	return nfs3_stat_to_errno(status);
2311 }
2312 
2313 /*
2314  * 3.3.21  COMMIT3res
2315  *
2316  *	struct COMMIT3resok {
2317  *		wcc_data	file_wcc;
2318  *		writeverf3	verf;
2319  *	};
2320  *
2321  *	struct COMMIT3resfail {
2322  *		wcc_data	file_wcc;
2323  *	};
2324  *
2325  *	union COMMIT3res switch (nfsstat3 status) {
2326  *	case NFS3_OK:
2327  *		COMMIT3resok	resok;
2328  *	default:
2329  *		COMMIT3resfail	resfail;
2330  *	};
2331  */
2332 static int nfs3_xdr_dec_commit3res(struct rpc_rqst *req,
2333 				   struct xdr_stream *xdr,
2334 				   void *data)
2335 {
2336 	struct nfs_commitres *result = data;
2337 	struct nfs_writeverf *verf = result->verf;
2338 	enum nfs_stat status;
2339 	int error;
2340 
2341 	error = decode_nfsstat3(xdr, &status);
2342 	if (unlikely(error))
2343 		goto out;
2344 	error = decode_wcc_data(xdr, result->fattr, rpc_rqst_userns(req));
2345 	if (unlikely(error))
2346 		goto out;
2347 	result->op_status = status;
2348 	if (status != NFS3_OK)
2349 		goto out_status;
2350 	error = decode_writeverf3(xdr, &verf->verifier);
2351 	if (!error)
2352 		verf->committed = NFS_FILE_SYNC;
2353 out:
2354 	return error;
2355 out_status:
2356 	return nfs3_stat_to_errno(status);
2357 }
2358 
2359 #ifdef CONFIG_NFS_V3_ACL
2360 
2361 static inline int decode_getacl3resok(struct xdr_stream *xdr,
2362 				      struct nfs3_getaclres *result,
2363 				      struct user_namespace *userns)
2364 {
2365 	struct posix_acl **acl;
2366 	unsigned int *aclcnt;
2367 	size_t hdrlen;
2368 	int error;
2369 
2370 	error = decode_post_op_attr(xdr, result->fattr, userns);
2371 	if (unlikely(error))
2372 		goto out;
2373 	error = decode_uint32(xdr, &result->mask);
2374 	if (unlikely(error))
2375 		goto out;
2376 	error = -EINVAL;
2377 	if (result->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT))
2378 		goto out;
2379 
2380 	hdrlen = xdr_stream_pos(xdr);
2381 
2382 	acl = NULL;
2383 	if (result->mask & NFS_ACL)
2384 		acl = &result->acl_access;
2385 	aclcnt = NULL;
2386 	if (result->mask & NFS_ACLCNT)
2387 		aclcnt = &result->acl_access_count;
2388 	error = nfsacl_decode(xdr->buf, hdrlen, aclcnt, acl);
2389 	if (unlikely(error <= 0))
2390 		goto out;
2391 
2392 	acl = NULL;
2393 	if (result->mask & NFS_DFACL)
2394 		acl = &result->acl_default;
2395 	aclcnt = NULL;
2396 	if (result->mask & NFS_DFACLCNT)
2397 		aclcnt = &result->acl_default_count;
2398 	error = nfsacl_decode(xdr->buf, hdrlen + error, aclcnt, acl);
2399 	if (unlikely(error <= 0))
2400 		return error;
2401 	error = 0;
2402 out:
2403 	return error;
2404 }
2405 
2406 static int nfs3_xdr_dec_getacl3res(struct rpc_rqst *req,
2407 				   struct xdr_stream *xdr,
2408 				   void *result)
2409 {
2410 	enum nfs_stat status;
2411 	int error;
2412 
2413 	error = decode_nfsstat3(xdr, &status);
2414 	if (unlikely(error))
2415 		goto out;
2416 	if (status != NFS3_OK)
2417 		goto out_default;
2418 	error = decode_getacl3resok(xdr, result, rpc_rqst_userns(req));
2419 out:
2420 	return error;
2421 out_default:
2422 	return nfs3_stat_to_errno(status);
2423 }
2424 
2425 static int nfs3_xdr_dec_setacl3res(struct rpc_rqst *req,
2426 				   struct xdr_stream *xdr,
2427 				   void *result)
2428 {
2429 	enum nfs_stat status;
2430 	int error;
2431 
2432 	error = decode_nfsstat3(xdr, &status);
2433 	if (unlikely(error))
2434 		goto out;
2435 	if (status != NFS3_OK)
2436 		goto out_default;
2437 	error = decode_post_op_attr(xdr, result, rpc_rqst_userns(req));
2438 out:
2439 	return error;
2440 out_default:
2441 	return nfs3_stat_to_errno(status);
2442 }
2443 
2444 #endif  /* CONFIG_NFS_V3_ACL */
2445 
2446 
2447 /*
2448  * We need to translate between nfs status return values and
2449  * the local errno values which may not be the same.
2450  */
2451 static const struct {
2452 	int stat;
2453 	int errno;
2454 } nfs_errtbl[] = {
2455 	{ NFS_OK,		0		},
2456 	{ NFSERR_PERM,		-EPERM		},
2457 	{ NFSERR_NOENT,		-ENOENT		},
2458 	{ NFSERR_IO,		-errno_NFSERR_IO},
2459 	{ NFSERR_NXIO,		-ENXIO		},
2460 /*	{ NFSERR_EAGAIN,	-EAGAIN		}, */
2461 	{ NFSERR_ACCES,		-EACCES		},
2462 	{ NFSERR_EXIST,		-EEXIST		},
2463 	{ NFSERR_XDEV,		-EXDEV		},
2464 	{ NFSERR_NODEV,		-ENODEV		},
2465 	{ NFSERR_NOTDIR,	-ENOTDIR	},
2466 	{ NFSERR_ISDIR,		-EISDIR		},
2467 	{ NFSERR_INVAL,		-EINVAL		},
2468 	{ NFSERR_FBIG,		-EFBIG		},
2469 	{ NFSERR_NOSPC,		-ENOSPC		},
2470 	{ NFSERR_ROFS,		-EROFS		},
2471 	{ NFSERR_MLINK,		-EMLINK		},
2472 	{ NFSERR_NAMETOOLONG,	-ENAMETOOLONG	},
2473 	{ NFSERR_NOTEMPTY,	-ENOTEMPTY	},
2474 	{ NFSERR_DQUOT,		-EDQUOT		},
2475 	{ NFSERR_STALE,		-ESTALE		},
2476 	{ NFSERR_REMOTE,	-EREMOTE	},
2477 #ifdef EWFLUSH
2478 	{ NFSERR_WFLUSH,	-EWFLUSH	},
2479 #endif
2480 	{ NFSERR_BADHANDLE,	-EBADHANDLE	},
2481 	{ NFSERR_NOT_SYNC,	-ENOTSYNC	},
2482 	{ NFSERR_BAD_COOKIE,	-EBADCOOKIE	},
2483 	{ NFSERR_NOTSUPP,	-ENOTSUPP	},
2484 	{ NFSERR_TOOSMALL,	-ETOOSMALL	},
2485 	{ NFSERR_SERVERFAULT,	-EREMOTEIO	},
2486 	{ NFSERR_BADTYPE,	-EBADTYPE	},
2487 	{ NFSERR_JUKEBOX,	-EJUKEBOX	},
2488 	{ -1,			-EIO		}
2489 };
2490 
2491 /**
2492  * nfs3_stat_to_errno - convert an NFS status code to a local errno
2493  * @status: NFS status code to convert
2494  *
2495  * Returns a local errno value, or -EIO if the NFS status code is
2496  * not recognized.  This function is used jointly by NFSv2 and NFSv3.
2497  */
2498 static int nfs3_stat_to_errno(enum nfs_stat status)
2499 {
2500 	int i;
2501 
2502 	for (i = 0; nfs_errtbl[i].stat != -1; i++) {
2503 		if (nfs_errtbl[i].stat == (int)status)
2504 			return nfs_errtbl[i].errno;
2505 	}
2506 	dprintk("NFS: Unrecognized nfs status value: %u\n", status);
2507 	return nfs_errtbl[i].errno;
2508 }
2509 
2510 
2511 #define PROC(proc, argtype, restype, timer)				\
2512 [NFS3PROC_##proc] = {							\
2513 	.p_proc      = NFS3PROC_##proc,					\
2514 	.p_encode    = nfs3_xdr_enc_##argtype##3args,			\
2515 	.p_decode    = nfs3_xdr_dec_##restype##3res,			\
2516 	.p_arglen    = NFS3_##argtype##args_sz,				\
2517 	.p_replen    = NFS3_##restype##res_sz,				\
2518 	.p_timer     = timer,						\
2519 	.p_statidx   = NFS3PROC_##proc,					\
2520 	.p_name      = #proc,						\
2521 	}
2522 
2523 const struct rpc_procinfo nfs3_procedures[] = {
2524 	PROC(GETATTR,		getattr,	getattr,	1),
2525 	PROC(SETATTR,		setattr,	setattr,	0),
2526 	PROC(LOOKUP,		lookup,		lookup,		2),
2527 	PROC(ACCESS,		access,		access,		1),
2528 	PROC(READLINK,		readlink,	readlink,	3),
2529 	PROC(READ,		read,		read,		3),
2530 	PROC(WRITE,		write,		write,		4),
2531 	PROC(CREATE,		create,		create,		0),
2532 	PROC(MKDIR,		mkdir,		create,		0),
2533 	PROC(SYMLINK,		symlink,	create,		0),
2534 	PROC(MKNOD,		mknod,		create,		0),
2535 	PROC(REMOVE,		remove,		remove,		0),
2536 	PROC(RMDIR,		lookup,		setattr,	0),
2537 	PROC(RENAME,		rename,		rename,		0),
2538 	PROC(LINK,		link,		link,		0),
2539 	PROC(READDIR,		readdir,	readdir,	3),
2540 	PROC(READDIRPLUS,	readdirplus,	readdir,	3),
2541 	PROC(FSSTAT,		getattr,	fsstat,		0),
2542 	PROC(FSINFO,		getattr,	fsinfo,		0),
2543 	PROC(PATHCONF,		getattr,	pathconf,	0),
2544 	PROC(COMMIT,		commit,		commit,		5),
2545 };
2546 
2547 static unsigned int nfs_version3_counts[ARRAY_SIZE(nfs3_procedures)];
2548 const struct rpc_version nfs_version3 = {
2549 	.number			= 3,
2550 	.nrprocs		= ARRAY_SIZE(nfs3_procedures),
2551 	.procs			= nfs3_procedures,
2552 	.counts			= nfs_version3_counts,
2553 };
2554 
2555 #ifdef CONFIG_NFS_V3_ACL
2556 static const struct rpc_procinfo nfs3_acl_procedures[] = {
2557 	[ACLPROC3_GETACL] = {
2558 		.p_proc = ACLPROC3_GETACL,
2559 		.p_encode = nfs3_xdr_enc_getacl3args,
2560 		.p_decode = nfs3_xdr_dec_getacl3res,
2561 		.p_arglen = ACL3_getaclargs_sz,
2562 		.p_replen = ACL3_getaclres_sz,
2563 		.p_timer = 1,
2564 		.p_name = "GETACL",
2565 	},
2566 	[ACLPROC3_SETACL] = {
2567 		.p_proc = ACLPROC3_SETACL,
2568 		.p_encode = nfs3_xdr_enc_setacl3args,
2569 		.p_decode = nfs3_xdr_dec_setacl3res,
2570 		.p_arglen = ACL3_setaclargs_sz,
2571 		.p_replen = ACL3_setaclres_sz,
2572 		.p_timer = 0,
2573 		.p_name = "SETACL",
2574 	},
2575 };
2576 
2577 static unsigned int nfs3_acl_counts[ARRAY_SIZE(nfs3_acl_procedures)];
2578 const struct rpc_version nfsacl_version3 = {
2579 	.number			= 3,
2580 	.nrprocs		= ARRAY_SIZE(nfs3_acl_procedures),
2581 	.procs			= nfs3_acl_procedures,
2582 	.counts			= nfs3_acl_counts,
2583 };
2584 #endif  /* CONFIG_NFS_V3_ACL */
2585