xref: /openbmc/linux/fs/nfs/nfs3xdr.c (revision 5497b23e)
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_pagepad_sz		(1) /* Page padding */
37 #define NFS3_fhandle_sz		(1+16)
38 #define NFS3_fh_sz		(NFS3_fhandle_sz)	/* shorthand */
39 #define NFS3_sattr_sz		(15)
40 #define NFS3_filename_sz	(1+(NFS3_MAXNAMLEN>>2))
41 #define NFS3_path_sz		(1+(NFS3_MAXPATHLEN>>2))
42 #define NFS3_fattr_sz		(21)
43 #define NFS3_cookieverf_sz	(NFS3_COOKIEVERFSIZE>>2)
44 #define NFS3_wcc_attr_sz	(6)
45 #define NFS3_pre_op_attr_sz	(1+NFS3_wcc_attr_sz)
46 #define NFS3_post_op_attr_sz	(1+NFS3_fattr_sz)
47 #define NFS3_wcc_data_sz	(NFS3_pre_op_attr_sz+NFS3_post_op_attr_sz)
48 #define NFS3_diropargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
49 
50 #define NFS3_getattrargs_sz	(NFS3_fh_sz)
51 #define NFS3_setattrargs_sz	(NFS3_fh_sz+NFS3_sattr_sz+3)
52 #define NFS3_lookupargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
53 #define NFS3_accessargs_sz	(NFS3_fh_sz+1)
54 #define NFS3_readlinkargs_sz	(NFS3_fh_sz)
55 #define NFS3_readargs_sz	(NFS3_fh_sz+3)
56 #define NFS3_writeargs_sz	(NFS3_fh_sz+5)
57 #define NFS3_createargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
58 #define NFS3_mkdirargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
59 #define NFS3_symlinkargs_sz	(NFS3_diropargs_sz+1+NFS3_sattr_sz)
60 #define NFS3_mknodargs_sz	(NFS3_diropargs_sz+2+NFS3_sattr_sz)
61 #define NFS3_removeargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
62 #define NFS3_renameargs_sz	(NFS3_diropargs_sz+NFS3_diropargs_sz)
63 #define NFS3_linkargs_sz		(NFS3_fh_sz+NFS3_diropargs_sz)
64 #define NFS3_readdirargs_sz	(NFS3_fh_sz+NFS3_cookieverf_sz+3)
65 #define NFS3_readdirplusargs_sz	(NFS3_fh_sz+NFS3_cookieverf_sz+4)
66 #define NFS3_commitargs_sz	(NFS3_fh_sz+3)
67 
68 #define NFS3_getattrres_sz	(1+NFS3_fattr_sz)
69 #define NFS3_setattrres_sz	(1+NFS3_wcc_data_sz)
70 #define NFS3_removeres_sz	(NFS3_setattrres_sz)
71 #define NFS3_lookupres_sz	(1+NFS3_fh_sz+(2 * NFS3_post_op_attr_sz))
72 #define NFS3_accessres_sz	(1+NFS3_post_op_attr_sz+1)
73 #define NFS3_readlinkres_sz	(1+NFS3_post_op_attr_sz+1+NFS3_pagepad_sz)
74 #define NFS3_readres_sz		(1+NFS3_post_op_attr_sz+3+NFS3_pagepad_sz)
75 #define NFS3_writeres_sz	(1+NFS3_wcc_data_sz+4)
76 #define NFS3_createres_sz	(1+NFS3_fh_sz+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
77 #define NFS3_renameres_sz	(1+(2 * NFS3_wcc_data_sz))
78 #define NFS3_linkres_sz		(1+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
79 #define NFS3_readdirres_sz	(1+NFS3_post_op_attr_sz+2+NFS3_pagepad_sz)
80 #define NFS3_fsstatres_sz	(1+NFS3_post_op_attr_sz+13)
81 #define NFS3_fsinfores_sz	(1+NFS3_post_op_attr_sz+12)
82 #define NFS3_pathconfres_sz	(1+NFS3_post_op_attr_sz+6)
83 #define NFS3_commitres_sz	(1+NFS3_wcc_data_sz+2)
84 
85 #define ACL3_getaclargs_sz	(NFS3_fh_sz+1)
86 #define ACL3_setaclargs_sz	(NFS3_fh_sz+1+ \
87 				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE))
88 #define ACL3_getaclres_sz	(1+NFS3_post_op_attr_sz+1+ \
89 				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE)+\
90 				NFS3_pagepad_sz)
91 #define ACL3_setaclres_sz	(1+NFS3_post_op_attr_sz)
92 
93 static int nfs3_stat_to_errno(enum nfs_stat);
94 
95 /*
96  * Map file type to S_IFMT bits
97  */
98 static const umode_t nfs_type2fmt[] = {
99 	[NF3BAD] = 0,
100 	[NF3REG] = S_IFREG,
101 	[NF3DIR] = S_IFDIR,
102 	[NF3BLK] = S_IFBLK,
103 	[NF3CHR] = S_IFCHR,
104 	[NF3LNK] = S_IFLNK,
105 	[NF3SOCK] = S_IFSOCK,
106 	[NF3FIFO] = S_IFIFO,
107 };
108 
109 static struct user_namespace *rpc_userns(const struct rpc_clnt *clnt)
110 {
111 	if (clnt && clnt->cl_cred)
112 		return clnt->cl_cred->user_ns;
113 	return &init_user_ns;
114 }
115 
116 static struct user_namespace *rpc_rqst_userns(const struct rpc_rqst *rqstp)
117 {
118 	if (rqstp->rq_task)
119 		return rpc_userns(rqstp->rq_task->tk_client);
120 	return &init_user_ns;
121 }
122 
123 /*
124  * Encode/decode NFSv3 basic data types
125  *
126  * Basic NFSv3 data types are defined in section 2.5 of RFC 1813:
127  * "NFS Version 3 Protocol Specification".
128  *
129  * Not all basic data types have their own encoding and decoding
130  * functions.  For run-time efficiency, some data types are encoded
131  * or decoded inline.
132  */
133 
134 static void encode_uint32(struct xdr_stream *xdr, u32 value)
135 {
136 	__be32 *p = xdr_reserve_space(xdr, 4);
137 	*p = cpu_to_be32(value);
138 }
139 
140 static int decode_uint32(struct xdr_stream *xdr, u32 *value)
141 {
142 	__be32 *p;
143 
144 	p = xdr_inline_decode(xdr, 4);
145 	if (unlikely(!p))
146 		return -EIO;
147 	*value = be32_to_cpup(p);
148 	return 0;
149 }
150 
151 static int decode_uint64(struct xdr_stream *xdr, u64 *value)
152 {
153 	__be32 *p;
154 
155 	p = xdr_inline_decode(xdr, 8);
156 	if (unlikely(!p))
157 		return -EIO;
158 	xdr_decode_hyper(p, value);
159 	return 0;
160 }
161 
162 /*
163  * fileid3
164  *
165  *	typedef uint64 fileid3;
166  */
167 static __be32 *xdr_decode_fileid3(__be32 *p, u64 *fileid)
168 {
169 	return xdr_decode_hyper(p, fileid);
170 }
171 
172 static int decode_fileid3(struct xdr_stream *xdr, u64 *fileid)
173 {
174 	return decode_uint64(xdr, fileid);
175 }
176 
177 /*
178  * filename3
179  *
180  *	typedef string filename3<>;
181  */
182 static void encode_filename3(struct xdr_stream *xdr,
183 			     const char *name, u32 length)
184 {
185 	__be32 *p;
186 
187 	WARN_ON_ONCE(length > NFS3_MAXNAMLEN);
188 	p = xdr_reserve_space(xdr, 4 + length);
189 	xdr_encode_opaque(p, name, length);
190 }
191 
192 static int decode_inline_filename3(struct xdr_stream *xdr,
193 				   const char **name, u32 *length)
194 {
195 	__be32 *p;
196 	u32 count;
197 
198 	p = xdr_inline_decode(xdr, 4);
199 	if (unlikely(!p))
200 		return -EIO;
201 	count = be32_to_cpup(p);
202 	if (count > NFS3_MAXNAMLEN)
203 		goto out_nametoolong;
204 	p = xdr_inline_decode(xdr, count);
205 	if (unlikely(!p))
206 		return -EIO;
207 	*name = (const char *)p;
208 	*length = count;
209 	return 0;
210 
211 out_nametoolong:
212 	dprintk("NFS: returned filename too long: %u\n", count);
213 	return -ENAMETOOLONG;
214 }
215 
216 /*
217  * nfspath3
218  *
219  *	typedef string nfspath3<>;
220  */
221 static void encode_nfspath3(struct xdr_stream *xdr, struct page **pages,
222 			    const u32 length)
223 {
224 	encode_uint32(xdr, length);
225 	xdr_write_pages(xdr, pages, 0, length);
226 }
227 
228 static int decode_nfspath3(struct xdr_stream *xdr)
229 {
230 	u32 recvd, count;
231 	__be32 *p;
232 
233 	p = xdr_inline_decode(xdr, 4);
234 	if (unlikely(!p))
235 		return -EIO;
236 	count = be32_to_cpup(p);
237 	if (unlikely(count >= xdr->buf->page_len || count > NFS3_MAXPATHLEN))
238 		goto out_nametoolong;
239 	recvd = xdr_read_pages(xdr, count);
240 	if (unlikely(count > recvd))
241 		goto out_cheating;
242 	xdr_terminate_string(xdr->buf, count);
243 	return 0;
244 
245 out_nametoolong:
246 	dprintk("NFS: returned pathname too long: %u\n", count);
247 	return -ENAMETOOLONG;
248 out_cheating:
249 	dprintk("NFS: server cheating in pathname result: "
250 		"count %u > recvd %u\n", count, recvd);
251 	return -EIO;
252 }
253 
254 /*
255  * cookie3
256  *
257  *	typedef uint64 cookie3
258  */
259 static __be32 *xdr_encode_cookie3(__be32 *p, u64 cookie)
260 {
261 	return xdr_encode_hyper(p, cookie);
262 }
263 
264 static int decode_cookie3(struct xdr_stream *xdr, u64 *cookie)
265 {
266 	return decode_uint64(xdr, cookie);
267 }
268 
269 /*
270  * cookieverf3
271  *
272  *	typedef opaque cookieverf3[NFS3_COOKIEVERFSIZE];
273  */
274 static __be32 *xdr_encode_cookieverf3(__be32 *p, const __be32 *verifier)
275 {
276 	memcpy(p, verifier, NFS3_COOKIEVERFSIZE);
277 	return p + XDR_QUADLEN(NFS3_COOKIEVERFSIZE);
278 }
279 
280 static int decode_cookieverf3(struct xdr_stream *xdr, __be32 *verifier)
281 {
282 	__be32 *p;
283 
284 	p = xdr_inline_decode(xdr, NFS3_COOKIEVERFSIZE);
285 	if (unlikely(!p))
286 		return -EIO;
287 	memcpy(verifier, p, NFS3_COOKIEVERFSIZE);
288 	return 0;
289 }
290 
291 /*
292  * createverf3
293  *
294  *	typedef opaque createverf3[NFS3_CREATEVERFSIZE];
295  */
296 static void encode_createverf3(struct xdr_stream *xdr, const __be32 *verifier)
297 {
298 	__be32 *p;
299 
300 	p = xdr_reserve_space(xdr, NFS3_CREATEVERFSIZE);
301 	memcpy(p, verifier, NFS3_CREATEVERFSIZE);
302 }
303 
304 static int decode_writeverf3(struct xdr_stream *xdr, struct nfs_write_verifier *verifier)
305 {
306 	__be32 *p;
307 
308 	p = xdr_inline_decode(xdr, NFS3_WRITEVERFSIZE);
309 	if (unlikely(!p))
310 		return -EIO;
311 	memcpy(verifier->data, p, NFS3_WRITEVERFSIZE);
312 	return 0;
313 }
314 
315 /*
316  * size3
317  *
318  *	typedef uint64 size3;
319  */
320 static __be32 *xdr_decode_size3(__be32 *p, u64 *size)
321 {
322 	return xdr_decode_hyper(p, size);
323 }
324 
325 /*
326  * nfsstat3
327  *
328  *	enum nfsstat3 {
329  *		NFS3_OK = 0,
330  *		...
331  *	}
332  */
333 #define NFS3_OK		NFS_OK
334 
335 static int decode_nfsstat3(struct xdr_stream *xdr, enum nfs_stat *status)
336 {
337 	__be32 *p;
338 
339 	p = xdr_inline_decode(xdr, 4);
340 	if (unlikely(!p))
341 		return -EIO;
342 	if (unlikely(*p != cpu_to_be32(NFS3_OK)))
343 		goto out_status;
344 	*status = 0;
345 	return 0;
346 out_status:
347 	*status = be32_to_cpup(p);
348 	trace_nfs_xdr_status(xdr, (int)*status);
349 	return 0;
350 }
351 
352 /*
353  * ftype3
354  *
355  *	enum ftype3 {
356  *		NF3REG	= 1,
357  *		NF3DIR	= 2,
358  *		NF3BLK	= 3,
359  *		NF3CHR	= 4,
360  *		NF3LNK	= 5,
361  *		NF3SOCK	= 6,
362  *		NF3FIFO	= 7
363  *	};
364  */
365 static void encode_ftype3(struct xdr_stream *xdr, const u32 type)
366 {
367 	encode_uint32(xdr, type);
368 }
369 
370 static __be32 *xdr_decode_ftype3(__be32 *p, umode_t *mode)
371 {
372 	u32 type;
373 
374 	type = be32_to_cpup(p++);
375 	if (type > NF3FIFO)
376 		type = NF3NON;
377 	*mode = nfs_type2fmt[type];
378 	return p;
379 }
380 
381 /*
382  * specdata3
383  *
384  *     struct specdata3 {
385  *             uint32  specdata1;
386  *             uint32  specdata2;
387  *     };
388  */
389 static void encode_specdata3(struct xdr_stream *xdr, const dev_t rdev)
390 {
391 	__be32 *p;
392 
393 	p = xdr_reserve_space(xdr, 8);
394 	*p++ = cpu_to_be32(MAJOR(rdev));
395 	*p = cpu_to_be32(MINOR(rdev));
396 }
397 
398 static __be32 *xdr_decode_specdata3(__be32 *p, dev_t *rdev)
399 {
400 	unsigned int major, minor;
401 
402 	major = be32_to_cpup(p++);
403 	minor = be32_to_cpup(p++);
404 	*rdev = MKDEV(major, minor);
405 	if (MAJOR(*rdev) != major || MINOR(*rdev) != minor)
406 		*rdev = 0;
407 	return p;
408 }
409 
410 /*
411  * nfs_fh3
412  *
413  *	struct nfs_fh3 {
414  *		opaque       data<NFS3_FHSIZE>;
415  *	};
416  */
417 static void encode_nfs_fh3(struct xdr_stream *xdr, const struct nfs_fh *fh)
418 {
419 	__be32 *p;
420 
421 	WARN_ON_ONCE(fh->size > NFS3_FHSIZE);
422 	p = xdr_reserve_space(xdr, 4 + fh->size);
423 	xdr_encode_opaque(p, fh->data, fh->size);
424 }
425 
426 static int decode_nfs_fh3(struct xdr_stream *xdr, struct nfs_fh *fh)
427 {
428 	u32 length;
429 	__be32 *p;
430 
431 	p = xdr_inline_decode(xdr, 4);
432 	if (unlikely(!p))
433 		return -EIO;
434 	length = be32_to_cpup(p++);
435 	if (unlikely(length > NFS3_FHSIZE))
436 		goto out_toobig;
437 	p = xdr_inline_decode(xdr, length);
438 	if (unlikely(!p))
439 		return -EIO;
440 	fh->size = length;
441 	memcpy(fh->data, p, length);
442 	return 0;
443 out_toobig:
444 	dprintk("NFS: file handle size (%u) too big\n", length);
445 	return -E2BIG;
446 }
447 
448 static void zero_nfs_fh3(struct nfs_fh *fh)
449 {
450 	memset(fh, 0, sizeof(*fh));
451 }
452 
453 /*
454  * nfstime3
455  *
456  *	struct nfstime3 {
457  *		uint32	seconds;
458  *		uint32	nseconds;
459  *	};
460  */
461 static __be32 *xdr_encode_nfstime3(__be32 *p, const struct timespec64 *timep)
462 {
463 	*p++ = cpu_to_be32((u32)timep->tv_sec);
464 	*p++ = cpu_to_be32(timep->tv_nsec);
465 	return p;
466 }
467 
468 static __be32 *xdr_decode_nfstime3(__be32 *p, struct timespec64 *timep)
469 {
470 	timep->tv_sec = be32_to_cpup(p++);
471 	timep->tv_nsec = be32_to_cpup(p++);
472 	return p;
473 }
474 
475 /*
476  * sattr3
477  *
478  *	enum time_how {
479  *		DONT_CHANGE		= 0,
480  *		SET_TO_SERVER_TIME	= 1,
481  *		SET_TO_CLIENT_TIME	= 2
482  *	};
483  *
484  *	union set_mode3 switch (bool set_it) {
485  *	case TRUE:
486  *		mode3	mode;
487  *	default:
488  *		void;
489  *	};
490  *
491  *	union set_uid3 switch (bool set_it) {
492  *	case TRUE:
493  *		uid3	uid;
494  *	default:
495  *		void;
496  *	};
497  *
498  *	union set_gid3 switch (bool set_it) {
499  *	case TRUE:
500  *		gid3	gid;
501  *	default:
502  *		void;
503  *	};
504  *
505  *	union set_size3 switch (bool set_it) {
506  *	case TRUE:
507  *		size3	size;
508  *	default:
509  *		void;
510  *	};
511  *
512  *	union set_atime switch (time_how set_it) {
513  *	case SET_TO_CLIENT_TIME:
514  *		nfstime3	atime;
515  *	default:
516  *		void;
517  *	};
518  *
519  *	union set_mtime switch (time_how set_it) {
520  *	case SET_TO_CLIENT_TIME:
521  *		nfstime3  mtime;
522  *	default:
523  *		void;
524  *	};
525  *
526  *	struct sattr3 {
527  *		set_mode3	mode;
528  *		set_uid3	uid;
529  *		set_gid3	gid;
530  *		set_size3	size;
531  *		set_atime	atime;
532  *		set_mtime	mtime;
533  *	};
534  */
535 static void encode_sattr3(struct xdr_stream *xdr, const struct iattr *attr,
536 		struct user_namespace *userns)
537 {
538 	u32 nbytes;
539 	__be32 *p;
540 
541 	/*
542 	 * In order to make only a single xdr_reserve_space() call,
543 	 * pre-compute the total number of bytes to be reserved.
544 	 * Six boolean values, one for each set_foo field, are always
545 	 * present in the encoded result, so start there.
546 	 */
547 	nbytes = 6 * 4;
548 	if (attr->ia_valid & ATTR_MODE)
549 		nbytes += 4;
550 	if (attr->ia_valid & ATTR_UID)
551 		nbytes += 4;
552 	if (attr->ia_valid & ATTR_GID)
553 		nbytes += 4;
554 	if (attr->ia_valid & ATTR_SIZE)
555 		nbytes += 8;
556 	if (attr->ia_valid & ATTR_ATIME_SET)
557 		nbytes += 8;
558 	if (attr->ia_valid & ATTR_MTIME_SET)
559 		nbytes += 8;
560 	p = xdr_reserve_space(xdr, nbytes);
561 
562 	if (attr->ia_valid & ATTR_MODE) {
563 		*p++ = xdr_one;
564 		*p++ = cpu_to_be32(attr->ia_mode & S_IALLUGO);
565 	} else
566 		*p++ = xdr_zero;
567 
568 	if (attr->ia_valid & ATTR_UID) {
569 		*p++ = xdr_one;
570 		*p++ = cpu_to_be32(from_kuid_munged(userns, attr->ia_uid));
571 	} else
572 		*p++ = xdr_zero;
573 
574 	if (attr->ia_valid & ATTR_GID) {
575 		*p++ = xdr_one;
576 		*p++ = cpu_to_be32(from_kgid_munged(userns, attr->ia_gid));
577 	} else
578 		*p++ = xdr_zero;
579 
580 	if (attr->ia_valid & ATTR_SIZE) {
581 		*p++ = xdr_one;
582 		p = xdr_encode_hyper(p, (u64)attr->ia_size);
583 	} else
584 		*p++ = xdr_zero;
585 
586 	if (attr->ia_valid & ATTR_ATIME_SET) {
587 		*p++ = xdr_two;
588 		p = xdr_encode_nfstime3(p, &attr->ia_atime);
589 	} else if (attr->ia_valid & ATTR_ATIME) {
590 		*p++ = xdr_one;
591 	} else
592 		*p++ = xdr_zero;
593 
594 	if (attr->ia_valid & ATTR_MTIME_SET) {
595 		*p++ = xdr_two;
596 		xdr_encode_nfstime3(p, &attr->ia_mtime);
597 	} else if (attr->ia_valid & ATTR_MTIME) {
598 		*p = xdr_one;
599 	} else
600 		*p = xdr_zero;
601 }
602 
603 /*
604  * fattr3
605  *
606  *	struct fattr3 {
607  *		ftype3		type;
608  *		mode3		mode;
609  *		uint32		nlink;
610  *		uid3		uid;
611  *		gid3		gid;
612  *		size3		size;
613  *		size3		used;
614  *		specdata3	rdev;
615  *		uint64		fsid;
616  *		fileid3		fileid;
617  *		nfstime3	atime;
618  *		nfstime3	mtime;
619  *		nfstime3	ctime;
620  *	};
621  */
622 static int decode_fattr3(struct xdr_stream *xdr, struct nfs_fattr *fattr,
623 		struct user_namespace *userns)
624 {
625 	umode_t fmode;
626 	__be32 *p;
627 
628 	p = xdr_inline_decode(xdr, NFS3_fattr_sz << 2);
629 	if (unlikely(!p))
630 		return -EIO;
631 
632 	p = xdr_decode_ftype3(p, &fmode);
633 
634 	fattr->mode = (be32_to_cpup(p++) & ~S_IFMT) | fmode;
635 	fattr->nlink = be32_to_cpup(p++);
636 	fattr->uid = make_kuid(userns, be32_to_cpup(p++));
637 	if (!uid_valid(fattr->uid))
638 		goto out_uid;
639 	fattr->gid = make_kgid(userns, be32_to_cpup(p++));
640 	if (!gid_valid(fattr->gid))
641 		goto out_gid;
642 
643 	p = xdr_decode_size3(p, &fattr->size);
644 	p = xdr_decode_size3(p, &fattr->du.nfs3.used);
645 	p = xdr_decode_specdata3(p, &fattr->rdev);
646 
647 	p = xdr_decode_hyper(p, &fattr->fsid.major);
648 	fattr->fsid.minor = 0;
649 
650 	p = xdr_decode_fileid3(p, &fattr->fileid);
651 	p = xdr_decode_nfstime3(p, &fattr->atime);
652 	p = xdr_decode_nfstime3(p, &fattr->mtime);
653 	xdr_decode_nfstime3(p, &fattr->ctime);
654 	fattr->change_attr = nfs_timespec_to_change_attr(&fattr->ctime);
655 
656 	fattr->valid |= NFS_ATTR_FATTR_V3;
657 	return 0;
658 out_uid:
659 	dprintk("NFS: returned invalid uid\n");
660 	return -EINVAL;
661 out_gid:
662 	dprintk("NFS: returned invalid gid\n");
663 	return -EINVAL;
664 }
665 
666 /*
667  * post_op_attr
668  *
669  *	union post_op_attr switch (bool attributes_follow) {
670  *	case TRUE:
671  *		fattr3	attributes;
672  *	case FALSE:
673  *		void;
674  *	};
675  */
676 static int decode_post_op_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr,
677 		struct user_namespace *userns)
678 {
679 	__be32 *p;
680 
681 	p = xdr_inline_decode(xdr, 4);
682 	if (unlikely(!p))
683 		return -EIO;
684 	if (*p != xdr_zero)
685 		return decode_fattr3(xdr, fattr, userns);
686 	return 0;
687 }
688 
689 /*
690  * wcc_attr
691  *	struct wcc_attr {
692  *		size3		size;
693  *		nfstime3	mtime;
694  *		nfstime3	ctime;
695  *	};
696  */
697 static int decode_wcc_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
698 {
699 	__be32 *p;
700 
701 	p = xdr_inline_decode(xdr, NFS3_wcc_attr_sz << 2);
702 	if (unlikely(!p))
703 		return -EIO;
704 
705 	fattr->valid |= NFS_ATTR_FATTR_PRESIZE
706 		| NFS_ATTR_FATTR_PRECHANGE
707 		| NFS_ATTR_FATTR_PREMTIME
708 		| NFS_ATTR_FATTR_PRECTIME;
709 
710 	p = xdr_decode_size3(p, &fattr->pre_size);
711 	p = xdr_decode_nfstime3(p, &fattr->pre_mtime);
712 	xdr_decode_nfstime3(p, &fattr->pre_ctime);
713 	fattr->pre_change_attr = nfs_timespec_to_change_attr(&fattr->pre_ctime);
714 
715 	return 0;
716 }
717 
718 /*
719  * pre_op_attr
720  *	union pre_op_attr switch (bool attributes_follow) {
721  *	case TRUE:
722  *		wcc_attr	attributes;
723  *	case FALSE:
724  *		void;
725  *	};
726  *
727  * wcc_data
728  *
729  *	struct wcc_data {
730  *		pre_op_attr	before;
731  *		post_op_attr	after;
732  *	};
733  */
734 static int decode_pre_op_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
735 {
736 	__be32 *p;
737 
738 	p = xdr_inline_decode(xdr, 4);
739 	if (unlikely(!p))
740 		return -EIO;
741 	if (*p != xdr_zero)
742 		return decode_wcc_attr(xdr, fattr);
743 	return 0;
744 }
745 
746 static int decode_wcc_data(struct xdr_stream *xdr, struct nfs_fattr *fattr,
747 		struct user_namespace *userns)
748 {
749 	int error;
750 
751 	error = decode_pre_op_attr(xdr, fattr);
752 	if (unlikely(error))
753 		goto out;
754 	error = decode_post_op_attr(xdr, fattr, userns);
755 out:
756 	return error;
757 }
758 
759 /*
760  * post_op_fh3
761  *
762  *	union post_op_fh3 switch (bool handle_follows) {
763  *	case TRUE:
764  *		nfs_fh3  handle;
765  *	case FALSE:
766  *		void;
767  *	};
768  */
769 static int decode_post_op_fh3(struct xdr_stream *xdr, struct nfs_fh *fh)
770 {
771 	__be32 *p = xdr_inline_decode(xdr, 4);
772 	if (unlikely(!p))
773 		return -EIO;
774 	if (*p != xdr_zero)
775 		return decode_nfs_fh3(xdr, fh);
776 	zero_nfs_fh3(fh);
777 	return 0;
778 }
779 
780 /*
781  * diropargs3
782  *
783  *	struct diropargs3 {
784  *		nfs_fh3		dir;
785  *		filename3	name;
786  *	};
787  */
788 static void encode_diropargs3(struct xdr_stream *xdr, const struct nfs_fh *fh,
789 			      const char *name, u32 length)
790 {
791 	encode_nfs_fh3(xdr, fh);
792 	encode_filename3(xdr, name, length);
793 }
794 
795 
796 /*
797  * NFSv3 XDR encode functions
798  *
799  * NFSv3 argument types are defined in section 3.3 of RFC 1813:
800  * "NFS Version 3 Protocol Specification".
801  */
802 
803 /*
804  * 3.3.1  GETATTR3args
805  *
806  *	struct GETATTR3args {
807  *		nfs_fh3  object;
808  *	};
809  */
810 static void nfs3_xdr_enc_getattr3args(struct rpc_rqst *req,
811 				      struct xdr_stream *xdr,
812 				      const void *data)
813 {
814 	const struct nfs_fh *fh = data;
815 
816 	encode_nfs_fh3(xdr, fh);
817 }
818 
819 /*
820  * 3.3.2  SETATTR3args
821  *
822  *	union sattrguard3 switch (bool check) {
823  *	case TRUE:
824  *		nfstime3  obj_ctime;
825  *	case FALSE:
826  *		void;
827  *	};
828  *
829  *	struct SETATTR3args {
830  *		nfs_fh3		object;
831  *		sattr3		new_attributes;
832  *		sattrguard3	guard;
833  *	};
834  */
835 static void encode_sattrguard3(struct xdr_stream *xdr,
836 			       const struct nfs3_sattrargs *args)
837 {
838 	__be32 *p;
839 
840 	if (args->guard) {
841 		p = xdr_reserve_space(xdr, 4 + 8);
842 		*p++ = xdr_one;
843 		xdr_encode_nfstime3(p, &args->guardtime);
844 	} else {
845 		p = xdr_reserve_space(xdr, 4);
846 		*p = xdr_zero;
847 	}
848 }
849 
850 static void nfs3_xdr_enc_setattr3args(struct rpc_rqst *req,
851 				      struct xdr_stream *xdr,
852 				      const void *data)
853 {
854 	const struct nfs3_sattrargs *args = data;
855 	encode_nfs_fh3(xdr, args->fh);
856 	encode_sattr3(xdr, args->sattr, rpc_rqst_userns(req));
857 	encode_sattrguard3(xdr, args);
858 }
859 
860 /*
861  * 3.3.3  LOOKUP3args
862  *
863  *	struct LOOKUP3args {
864  *		diropargs3  what;
865  *	};
866  */
867 static void nfs3_xdr_enc_lookup3args(struct rpc_rqst *req,
868 				     struct xdr_stream *xdr,
869 				     const void *data)
870 {
871 	const struct nfs3_diropargs *args = data;
872 
873 	encode_diropargs3(xdr, args->fh, args->name, args->len);
874 }
875 
876 /*
877  * 3.3.4  ACCESS3args
878  *
879  *	struct ACCESS3args {
880  *		nfs_fh3		object;
881  *		uint32		access;
882  *	};
883  */
884 static void encode_access3args(struct xdr_stream *xdr,
885 			       const struct nfs3_accessargs *args)
886 {
887 	encode_nfs_fh3(xdr, args->fh);
888 	encode_uint32(xdr, args->access);
889 }
890 
891 static void nfs3_xdr_enc_access3args(struct rpc_rqst *req,
892 				     struct xdr_stream *xdr,
893 				     const void *data)
894 {
895 	const struct nfs3_accessargs *args = data;
896 
897 	encode_access3args(xdr, args);
898 }
899 
900 /*
901  * 3.3.5  READLINK3args
902  *
903  *	struct READLINK3args {
904  *		nfs_fh3	symlink;
905  *	};
906  */
907 static void nfs3_xdr_enc_readlink3args(struct rpc_rqst *req,
908 				       struct xdr_stream *xdr,
909 				       const void *data)
910 {
911 	const struct nfs3_readlinkargs *args = data;
912 
913 	encode_nfs_fh3(xdr, args->fh);
914 	rpc_prepare_reply_pages(req, args->pages, args->pgbase, args->pglen,
915 				NFS3_readlinkres_sz - NFS3_pagepad_sz);
916 }
917 
918 /*
919  * 3.3.6  READ3args
920  *
921  *	struct READ3args {
922  *		nfs_fh3		file;
923  *		offset3		offset;
924  *		count3		count;
925  *	};
926  */
927 static void encode_read3args(struct xdr_stream *xdr,
928 			     const struct nfs_pgio_args *args)
929 {
930 	__be32 *p;
931 
932 	encode_nfs_fh3(xdr, args->fh);
933 
934 	p = xdr_reserve_space(xdr, 8 + 4);
935 	p = xdr_encode_hyper(p, args->offset);
936 	*p = cpu_to_be32(args->count);
937 }
938 
939 static void nfs3_xdr_enc_read3args(struct rpc_rqst *req,
940 				   struct xdr_stream *xdr,
941 				   const void *data)
942 {
943 	const struct nfs_pgio_args *args = data;
944 	unsigned int replen = args->replen ? args->replen :
945 					     NFS3_readres_sz - NFS3_pagepad_sz;
946 
947 	encode_read3args(xdr, args);
948 	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
949 				args->count, replen);
950 	req->rq_rcv_buf.flags |= XDRBUF_READ;
951 }
952 
953 /*
954  * 3.3.7  WRITE3args
955  *
956  *	enum stable_how {
957  *		UNSTABLE  = 0,
958  *		DATA_SYNC = 1,
959  *		FILE_SYNC = 2
960  *	};
961  *
962  *	struct WRITE3args {
963  *		nfs_fh3		file;
964  *		offset3		offset;
965  *		count3		count;
966  *		stable_how	stable;
967  *		opaque		data<>;
968  *	};
969  */
970 static void encode_write3args(struct xdr_stream *xdr,
971 			      const struct nfs_pgio_args *args)
972 {
973 	__be32 *p;
974 
975 	encode_nfs_fh3(xdr, args->fh);
976 
977 	p = xdr_reserve_space(xdr, 8 + 4 + 4 + 4);
978 	p = xdr_encode_hyper(p, args->offset);
979 	*p++ = cpu_to_be32(args->count);
980 	*p++ = cpu_to_be32(args->stable);
981 	*p = cpu_to_be32(args->count);
982 	xdr_write_pages(xdr, args->pages, args->pgbase, args->count);
983 }
984 
985 static void nfs3_xdr_enc_write3args(struct rpc_rqst *req,
986 				    struct xdr_stream *xdr,
987 				    const void *data)
988 {
989 	const struct nfs_pgio_args *args = data;
990 
991 	encode_write3args(xdr, args);
992 	xdr->buf->flags |= XDRBUF_WRITE;
993 }
994 
995 /*
996  * 3.3.8  CREATE3args
997  *
998  *	enum createmode3 {
999  *		UNCHECKED = 0,
1000  *		GUARDED   = 1,
1001  *		EXCLUSIVE = 2
1002  *	};
1003  *
1004  *	union createhow3 switch (createmode3 mode) {
1005  *	case UNCHECKED:
1006  *	case GUARDED:
1007  *		sattr3       obj_attributes;
1008  *	case EXCLUSIVE:
1009  *		createverf3  verf;
1010  *	};
1011  *
1012  *	struct CREATE3args {
1013  *		diropargs3	where;
1014  *		createhow3	how;
1015  *	};
1016  */
1017 static void encode_createhow3(struct xdr_stream *xdr,
1018 			      const struct nfs3_createargs *args,
1019 			      struct user_namespace *userns)
1020 {
1021 	encode_uint32(xdr, args->createmode);
1022 	switch (args->createmode) {
1023 	case NFS3_CREATE_UNCHECKED:
1024 	case NFS3_CREATE_GUARDED:
1025 		encode_sattr3(xdr, args->sattr, userns);
1026 		break;
1027 	case NFS3_CREATE_EXCLUSIVE:
1028 		encode_createverf3(xdr, args->verifier);
1029 		break;
1030 	default:
1031 		BUG();
1032 	}
1033 }
1034 
1035 static void nfs3_xdr_enc_create3args(struct rpc_rqst *req,
1036 				     struct xdr_stream *xdr,
1037 				     const void *data)
1038 {
1039 	const struct nfs3_createargs *args = data;
1040 
1041 	encode_diropargs3(xdr, args->fh, args->name, args->len);
1042 	encode_createhow3(xdr, args, rpc_rqst_userns(req));
1043 }
1044 
1045 /*
1046  * 3.3.9  MKDIR3args
1047  *
1048  *	struct MKDIR3args {
1049  *		diropargs3	where;
1050  *		sattr3		attributes;
1051  *	};
1052  */
1053 static void nfs3_xdr_enc_mkdir3args(struct rpc_rqst *req,
1054 				    struct xdr_stream *xdr,
1055 				    const void *data)
1056 {
1057 	const struct nfs3_mkdirargs *args = data;
1058 
1059 	encode_diropargs3(xdr, args->fh, args->name, args->len);
1060 	encode_sattr3(xdr, args->sattr, rpc_rqst_userns(req));
1061 }
1062 
1063 /*
1064  * 3.3.10  SYMLINK3args
1065  *
1066  *	struct symlinkdata3 {
1067  *		sattr3		symlink_attributes;
1068  *		nfspath3	symlink_data;
1069  *	};
1070  *
1071  *	struct SYMLINK3args {
1072  *		diropargs3	where;
1073  *		symlinkdata3	symlink;
1074  *	};
1075  */
1076 static void encode_symlinkdata3(struct xdr_stream *xdr,
1077 				const void *data,
1078 				struct user_namespace *userns)
1079 {
1080 	const struct nfs3_symlinkargs *args = data;
1081 
1082 	encode_sattr3(xdr, args->sattr, userns);
1083 	encode_nfspath3(xdr, args->pages, args->pathlen);
1084 }
1085 
1086 static void nfs3_xdr_enc_symlink3args(struct rpc_rqst *req,
1087 				      struct xdr_stream *xdr,
1088 				      const void *data)
1089 {
1090 	const struct nfs3_symlinkargs *args = data;
1091 
1092 	encode_diropargs3(xdr, args->fromfh, args->fromname, args->fromlen);
1093 	encode_symlinkdata3(xdr, args, rpc_rqst_userns(req));
1094 	xdr->buf->flags |= XDRBUF_WRITE;
1095 }
1096 
1097 /*
1098  * 3.3.11  MKNOD3args
1099  *
1100  *	struct devicedata3 {
1101  *		sattr3		dev_attributes;
1102  *		specdata3	spec;
1103  *	};
1104  *
1105  *	union mknoddata3 switch (ftype3 type) {
1106  *	case NF3CHR:
1107  *	case NF3BLK:
1108  *		devicedata3	device;
1109  *	case NF3SOCK:
1110  *	case NF3FIFO:
1111  *		sattr3		pipe_attributes;
1112  *	default:
1113  *		void;
1114  *	};
1115  *
1116  *	struct MKNOD3args {
1117  *		diropargs3	where;
1118  *		mknoddata3	what;
1119  *	};
1120  */
1121 static void encode_devicedata3(struct xdr_stream *xdr,
1122 			       const struct nfs3_mknodargs *args,
1123 			       struct user_namespace *userns)
1124 {
1125 	encode_sattr3(xdr, args->sattr, userns);
1126 	encode_specdata3(xdr, args->rdev);
1127 }
1128 
1129 static void encode_mknoddata3(struct xdr_stream *xdr,
1130 			      const struct nfs3_mknodargs *args,
1131 			      struct user_namespace *userns)
1132 {
1133 	encode_ftype3(xdr, args->type);
1134 	switch (args->type) {
1135 	case NF3CHR:
1136 	case NF3BLK:
1137 		encode_devicedata3(xdr, args, userns);
1138 		break;
1139 	case NF3SOCK:
1140 	case NF3FIFO:
1141 		encode_sattr3(xdr, args->sattr, userns);
1142 		break;
1143 	case NF3REG:
1144 	case NF3DIR:
1145 		break;
1146 	default:
1147 		BUG();
1148 	}
1149 }
1150 
1151 static void nfs3_xdr_enc_mknod3args(struct rpc_rqst *req,
1152 				    struct xdr_stream *xdr,
1153 				    const void *data)
1154 {
1155 	const struct nfs3_mknodargs *args = data;
1156 
1157 	encode_diropargs3(xdr, args->fh, args->name, args->len);
1158 	encode_mknoddata3(xdr, args, rpc_rqst_userns(req));
1159 }
1160 
1161 /*
1162  * 3.3.12  REMOVE3args
1163  *
1164  *	struct REMOVE3args {
1165  *		diropargs3  object;
1166  *	};
1167  */
1168 static void nfs3_xdr_enc_remove3args(struct rpc_rqst *req,
1169 				     struct xdr_stream *xdr,
1170 				     const void *data)
1171 {
1172 	const struct nfs_removeargs *args = data;
1173 
1174 	encode_diropargs3(xdr, args->fh, args->name.name, args->name.len);
1175 }
1176 
1177 /*
1178  * 3.3.14  RENAME3args
1179  *
1180  *	struct RENAME3args {
1181  *		diropargs3	from;
1182  *		diropargs3	to;
1183  *	};
1184  */
1185 static void nfs3_xdr_enc_rename3args(struct rpc_rqst *req,
1186 				     struct xdr_stream *xdr,
1187 				     const void *data)
1188 {
1189 	const struct nfs_renameargs *args = data;
1190 	const struct qstr *old = args->old_name;
1191 	const struct qstr *new = args->new_name;
1192 
1193 	encode_diropargs3(xdr, args->old_dir, old->name, old->len);
1194 	encode_diropargs3(xdr, args->new_dir, new->name, new->len);
1195 }
1196 
1197 /*
1198  * 3.3.15  LINK3args
1199  *
1200  *	struct LINK3args {
1201  *		nfs_fh3		file;
1202  *		diropargs3	link;
1203  *	};
1204  */
1205 static void nfs3_xdr_enc_link3args(struct rpc_rqst *req,
1206 				   struct xdr_stream *xdr,
1207 				   const void *data)
1208 {
1209 	const struct nfs3_linkargs *args = data;
1210 
1211 	encode_nfs_fh3(xdr, args->fromfh);
1212 	encode_diropargs3(xdr, args->tofh, args->toname, args->tolen);
1213 }
1214 
1215 /*
1216  * 3.3.16  READDIR3args
1217  *
1218  *	struct READDIR3args {
1219  *		nfs_fh3		dir;
1220  *		cookie3		cookie;
1221  *		cookieverf3	cookieverf;
1222  *		count3		count;
1223  *	};
1224  */
1225 static void encode_readdir3args(struct xdr_stream *xdr,
1226 				const struct nfs3_readdirargs *args)
1227 {
1228 	__be32 *p;
1229 
1230 	encode_nfs_fh3(xdr, args->fh);
1231 
1232 	p = xdr_reserve_space(xdr, 8 + NFS3_COOKIEVERFSIZE + 4);
1233 	p = xdr_encode_cookie3(p, args->cookie);
1234 	p = xdr_encode_cookieverf3(p, args->verf);
1235 	*p = cpu_to_be32(args->count);
1236 }
1237 
1238 static void nfs3_xdr_enc_readdir3args(struct rpc_rqst *req,
1239 				      struct xdr_stream *xdr,
1240 				      const void *data)
1241 {
1242 	const struct nfs3_readdirargs *args = data;
1243 
1244 	encode_readdir3args(xdr, args);
1245 	rpc_prepare_reply_pages(req, args->pages, 0, args->count,
1246 				NFS3_readdirres_sz - NFS3_pagepad_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 void *data)
1283 {
1284 	const struct nfs3_readdirargs *args = data;
1285 
1286 	encode_readdirplus3args(xdr, args);
1287 	rpc_prepare_reply_pages(req, args->pages, 0, args->count,
1288 				NFS3_readdirres_sz - NFS3_pagepad_sz);
1289 }
1290 
1291 /*
1292  * 3.3.21  COMMIT3args
1293  *
1294  *	struct COMMIT3args {
1295  *		nfs_fh3		file;
1296  *		offset3		offset;
1297  *		count3		count;
1298  *	};
1299  */
1300 static void encode_commit3args(struct xdr_stream *xdr,
1301 			       const struct nfs_commitargs *args)
1302 {
1303 	__be32 *p;
1304 
1305 	encode_nfs_fh3(xdr, args->fh);
1306 
1307 	p = xdr_reserve_space(xdr, 8 + 4);
1308 	p = xdr_encode_hyper(p, args->offset);
1309 	*p = cpu_to_be32(args->count);
1310 }
1311 
1312 static void nfs3_xdr_enc_commit3args(struct rpc_rqst *req,
1313 				     struct xdr_stream *xdr,
1314 				     const void *data)
1315 {
1316 	const struct nfs_commitargs *args = data;
1317 
1318 	encode_commit3args(xdr, args);
1319 }
1320 
1321 #ifdef CONFIG_NFS_V3_ACL
1322 
1323 static void nfs3_xdr_enc_getacl3args(struct rpc_rqst *req,
1324 				     struct xdr_stream *xdr,
1325 				     const void *data)
1326 {
1327 	const struct nfs3_getaclargs *args = data;
1328 
1329 	encode_nfs_fh3(xdr, args->fh);
1330 	encode_uint32(xdr, args->mask);
1331 	if (args->mask & (NFS_ACL | NFS_DFACL)) {
1332 		rpc_prepare_reply_pages(req, args->pages, 0,
1333 					NFSACL_MAXPAGES << PAGE_SHIFT,
1334 					ACL3_getaclres_sz - NFS3_pagepad_sz);
1335 		req->rq_rcv_buf.flags |= XDRBUF_SPARSE_PAGES;
1336 	}
1337 }
1338 
1339 static void nfs3_xdr_enc_setacl3args(struct rpc_rqst *req,
1340 				     struct xdr_stream *xdr,
1341 				     const void *data)
1342 {
1343 	const struct nfs3_setaclargs *args = data;
1344 	unsigned int base;
1345 	int error;
1346 
1347 	encode_nfs_fh3(xdr, NFS_FH(args->inode));
1348 	encode_uint32(xdr, args->mask);
1349 
1350 	base = req->rq_slen;
1351 	if (args->npages != 0)
1352 		xdr_write_pages(xdr, args->pages, 0, args->len);
1353 	else
1354 		xdr_reserve_space(xdr, args->len);
1355 
1356 	error = nfsacl_encode(xdr->buf, base, args->inode,
1357 			    (args->mask & NFS_ACL) ?
1358 			    args->acl_access : NULL, 1, 0);
1359 	/* FIXME: this is just broken */
1360 	BUG_ON(error < 0);
1361 	error = nfsacl_encode(xdr->buf, base + error, args->inode,
1362 			    (args->mask & NFS_DFACL) ?
1363 			    args->acl_default : NULL, 1,
1364 			    NFS_ACL_DEFAULT);
1365 	BUG_ON(error < 0);
1366 }
1367 
1368 #endif  /* CONFIG_NFS_V3_ACL */
1369 
1370 /*
1371  * NFSv3 XDR decode functions
1372  *
1373  * NFSv3 result types are defined in section 3.3 of RFC 1813:
1374  * "NFS Version 3 Protocol Specification".
1375  */
1376 
1377 /*
1378  * 3.3.1  GETATTR3res
1379  *
1380  *	struct GETATTR3resok {
1381  *		fattr3		obj_attributes;
1382  *	};
1383  *
1384  *	union GETATTR3res switch (nfsstat3 status) {
1385  *	case NFS3_OK:
1386  *		GETATTR3resok  resok;
1387  *	default:
1388  *		void;
1389  *	};
1390  */
1391 static int nfs3_xdr_dec_getattr3res(struct rpc_rqst *req,
1392 				    struct xdr_stream *xdr,
1393 				    void *result)
1394 {
1395 	enum nfs_stat status;
1396 	int error;
1397 
1398 	error = decode_nfsstat3(xdr, &status);
1399 	if (unlikely(error))
1400 		goto out;
1401 	if (status != NFS3_OK)
1402 		goto out_default;
1403 	error = decode_fattr3(xdr, result, rpc_rqst_userns(req));
1404 out:
1405 	return error;
1406 out_default:
1407 	return nfs3_stat_to_errno(status);
1408 }
1409 
1410 /*
1411  * 3.3.2  SETATTR3res
1412  *
1413  *	struct SETATTR3resok {
1414  *		wcc_data  obj_wcc;
1415  *	};
1416  *
1417  *	struct SETATTR3resfail {
1418  *		wcc_data  obj_wcc;
1419  *	};
1420  *
1421  *	union SETATTR3res switch (nfsstat3 status) {
1422  *	case NFS3_OK:
1423  *		SETATTR3resok   resok;
1424  *	default:
1425  *		SETATTR3resfail resfail;
1426  *	};
1427  */
1428 static int nfs3_xdr_dec_setattr3res(struct rpc_rqst *req,
1429 				    struct xdr_stream *xdr,
1430 				    void *result)
1431 {
1432 	enum nfs_stat status;
1433 	int error;
1434 
1435 	error = decode_nfsstat3(xdr, &status);
1436 	if (unlikely(error))
1437 		goto out;
1438 	error = decode_wcc_data(xdr, result, rpc_rqst_userns(req));
1439 	if (unlikely(error))
1440 		goto out;
1441 	if (status != NFS3_OK)
1442 		goto out_status;
1443 out:
1444 	return error;
1445 out_status:
1446 	return nfs3_stat_to_errno(status);
1447 }
1448 
1449 /*
1450  * 3.3.3  LOOKUP3res
1451  *
1452  *	struct LOOKUP3resok {
1453  *		nfs_fh3		object;
1454  *		post_op_attr	obj_attributes;
1455  *		post_op_attr	dir_attributes;
1456  *	};
1457  *
1458  *	struct LOOKUP3resfail {
1459  *		post_op_attr	dir_attributes;
1460  *	};
1461  *
1462  *	union LOOKUP3res switch (nfsstat3 status) {
1463  *	case NFS3_OK:
1464  *		LOOKUP3resok	resok;
1465  *	default:
1466  *		LOOKUP3resfail	resfail;
1467  *	};
1468  */
1469 static int nfs3_xdr_dec_lookup3res(struct rpc_rqst *req,
1470 				   struct xdr_stream *xdr,
1471 				   void *data)
1472 {
1473 	struct user_namespace *userns = rpc_rqst_userns(req);
1474 	struct nfs3_diropres *result = data;
1475 	enum nfs_stat status;
1476 	int error;
1477 
1478 	error = decode_nfsstat3(xdr, &status);
1479 	if (unlikely(error))
1480 		goto out;
1481 	if (status != NFS3_OK)
1482 		goto out_default;
1483 	error = decode_nfs_fh3(xdr, result->fh);
1484 	if (unlikely(error))
1485 		goto out;
1486 	error = decode_post_op_attr(xdr, result->fattr, userns);
1487 	if (unlikely(error))
1488 		goto out;
1489 	error = decode_post_op_attr(xdr, result->dir_attr, userns);
1490 out:
1491 	return error;
1492 out_default:
1493 	error = decode_post_op_attr(xdr, result->dir_attr, userns);
1494 	if (unlikely(error))
1495 		goto out;
1496 	return nfs3_stat_to_errno(status);
1497 }
1498 
1499 /*
1500  * 3.3.4  ACCESS3res
1501  *
1502  *	struct ACCESS3resok {
1503  *		post_op_attr	obj_attributes;
1504  *		uint32		access;
1505  *	};
1506  *
1507  *	struct ACCESS3resfail {
1508  *		post_op_attr	obj_attributes;
1509  *	};
1510  *
1511  *	union ACCESS3res switch (nfsstat3 status) {
1512  *	case NFS3_OK:
1513  *		ACCESS3resok	resok;
1514  *	default:
1515  *		ACCESS3resfail	resfail;
1516  *	};
1517  */
1518 static int nfs3_xdr_dec_access3res(struct rpc_rqst *req,
1519 				   struct xdr_stream *xdr,
1520 				   void *data)
1521 {
1522 	struct nfs3_accessres *result = data;
1523 	enum nfs_stat status;
1524 	int error;
1525 
1526 	error = decode_nfsstat3(xdr, &status);
1527 	if (unlikely(error))
1528 		goto out;
1529 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
1530 	if (unlikely(error))
1531 		goto out;
1532 	if (status != NFS3_OK)
1533 		goto out_default;
1534 	error = decode_uint32(xdr, &result->access);
1535 out:
1536 	return error;
1537 out_default:
1538 	return nfs3_stat_to_errno(status);
1539 }
1540 
1541 /*
1542  * 3.3.5  READLINK3res
1543  *
1544  *	struct READLINK3resok {
1545  *		post_op_attr	symlink_attributes;
1546  *		nfspath3	data;
1547  *	};
1548  *
1549  *	struct READLINK3resfail {
1550  *		post_op_attr	symlink_attributes;
1551  *	};
1552  *
1553  *	union READLINK3res switch (nfsstat3 status) {
1554  *	case NFS3_OK:
1555  *		READLINK3resok	resok;
1556  *	default:
1557  *		READLINK3resfail resfail;
1558  *	};
1559  */
1560 static int nfs3_xdr_dec_readlink3res(struct rpc_rqst *req,
1561 				     struct xdr_stream *xdr,
1562 				     void *result)
1563 {
1564 	enum nfs_stat status;
1565 	int error;
1566 
1567 	error = decode_nfsstat3(xdr, &status);
1568 	if (unlikely(error))
1569 		goto out;
1570 	error = decode_post_op_attr(xdr, result, rpc_rqst_userns(req));
1571 	if (unlikely(error))
1572 		goto out;
1573 	if (status != NFS3_OK)
1574 		goto out_default;
1575 	error = decode_nfspath3(xdr);
1576 out:
1577 	return error;
1578 out_default:
1579 	return nfs3_stat_to_errno(status);
1580 }
1581 
1582 /*
1583  * 3.3.6  READ3res
1584  *
1585  *	struct READ3resok {
1586  *		post_op_attr	file_attributes;
1587  *		count3		count;
1588  *		bool		eof;
1589  *		opaque		data<>;
1590  *	};
1591  *
1592  *	struct READ3resfail {
1593  *		post_op_attr	file_attributes;
1594  *	};
1595  *
1596  *	union READ3res switch (nfsstat3 status) {
1597  *	case NFS3_OK:
1598  *		READ3resok	resok;
1599  *	default:
1600  *		READ3resfail	resfail;
1601  *	};
1602  */
1603 static int decode_read3resok(struct xdr_stream *xdr,
1604 			     struct nfs_pgio_res *result)
1605 {
1606 	u32 eof, count, ocount, recvd;
1607 	__be32 *p;
1608 
1609 	p = xdr_inline_decode(xdr, 4 + 4 + 4);
1610 	if (unlikely(!p))
1611 		return -EIO;
1612 	count = be32_to_cpup(p++);
1613 	eof = be32_to_cpup(p++);
1614 	ocount = be32_to_cpup(p++);
1615 	if (unlikely(ocount != count))
1616 		goto out_mismatch;
1617 	recvd = xdr_read_pages(xdr, count);
1618 	if (unlikely(count > recvd))
1619 		goto out_cheating;
1620 out:
1621 	result->eof = eof;
1622 	result->count = count;
1623 	return count;
1624 out_mismatch:
1625 	dprintk("NFS: READ count doesn't match length of opaque: "
1626 		"count %u != ocount %u\n", count, ocount);
1627 	return -EIO;
1628 out_cheating:
1629 	dprintk("NFS: server cheating in read result: "
1630 		"count %u > recvd %u\n", count, recvd);
1631 	count = recvd;
1632 	eof = 0;
1633 	goto out;
1634 }
1635 
1636 static int nfs3_xdr_dec_read3res(struct rpc_rqst *req, struct xdr_stream *xdr,
1637 				 void *data)
1638 {
1639 	struct nfs_pgio_res *result = data;
1640 	unsigned int pos;
1641 	enum nfs_stat status;
1642 	int error;
1643 
1644 	pos = xdr_stream_pos(xdr);
1645 	error = decode_nfsstat3(xdr, &status);
1646 	if (unlikely(error))
1647 		goto out;
1648 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
1649 	if (unlikely(error))
1650 		goto out;
1651 	result->op_status = status;
1652 	if (status != NFS3_OK)
1653 		goto out_status;
1654 	result->replen = 3 + ((xdr_stream_pos(xdr) - pos) >> 2);
1655 	error = decode_read3resok(xdr, result);
1656 out:
1657 	return error;
1658 out_status:
1659 	return nfs3_stat_to_errno(status);
1660 }
1661 
1662 /*
1663  * 3.3.7  WRITE3res
1664  *
1665  *	enum stable_how {
1666  *		UNSTABLE  = 0,
1667  *		DATA_SYNC = 1,
1668  *		FILE_SYNC = 2
1669  *	};
1670  *
1671  *	struct WRITE3resok {
1672  *		wcc_data	file_wcc;
1673  *		count3		count;
1674  *		stable_how	committed;
1675  *		writeverf3	verf;
1676  *	};
1677  *
1678  *	struct WRITE3resfail {
1679  *		wcc_data	file_wcc;
1680  *	};
1681  *
1682  *	union WRITE3res switch (nfsstat3 status) {
1683  *	case NFS3_OK:
1684  *		WRITE3resok	resok;
1685  *	default:
1686  *		WRITE3resfail	resfail;
1687  *	};
1688  */
1689 static int decode_write3resok(struct xdr_stream *xdr,
1690 			      struct nfs_pgio_res *result)
1691 {
1692 	__be32 *p;
1693 
1694 	p = xdr_inline_decode(xdr, 4 + 4);
1695 	if (unlikely(!p))
1696 		return -EIO;
1697 	result->count = be32_to_cpup(p++);
1698 	result->verf->committed = be32_to_cpup(p++);
1699 	if (unlikely(result->verf->committed > NFS_FILE_SYNC))
1700 		goto out_badvalue;
1701 	if (decode_writeverf3(xdr, &result->verf->verifier))
1702 		return -EIO;
1703 	return result->count;
1704 out_badvalue:
1705 	dprintk("NFS: bad stable_how value: %u\n", result->verf->committed);
1706 	return -EIO;
1707 }
1708 
1709 static int nfs3_xdr_dec_write3res(struct rpc_rqst *req, struct xdr_stream *xdr,
1710 				  void *data)
1711 {
1712 	struct nfs_pgio_res *result = data;
1713 	enum nfs_stat status;
1714 	int error;
1715 
1716 	error = decode_nfsstat3(xdr, &status);
1717 	if (unlikely(error))
1718 		goto out;
1719 	error = decode_wcc_data(xdr, result->fattr, rpc_rqst_userns(req));
1720 	if (unlikely(error))
1721 		goto out;
1722 	result->op_status = status;
1723 	if (status != NFS3_OK)
1724 		goto out_status;
1725 	error = decode_write3resok(xdr, result);
1726 out:
1727 	return error;
1728 out_status:
1729 	return nfs3_stat_to_errno(status);
1730 }
1731 
1732 /*
1733  * 3.3.8  CREATE3res
1734  *
1735  *	struct CREATE3resok {
1736  *		post_op_fh3	obj;
1737  *		post_op_attr	obj_attributes;
1738  *		wcc_data	dir_wcc;
1739  *	};
1740  *
1741  *	struct CREATE3resfail {
1742  *		wcc_data	dir_wcc;
1743  *	};
1744  *
1745  *	union CREATE3res switch (nfsstat3 status) {
1746  *	case NFS3_OK:
1747  *		CREATE3resok	resok;
1748  *	default:
1749  *		CREATE3resfail	resfail;
1750  *	};
1751  */
1752 static int decode_create3resok(struct xdr_stream *xdr,
1753 			       struct nfs3_diropres *result,
1754 			       struct user_namespace *userns)
1755 {
1756 	int error;
1757 
1758 	error = decode_post_op_fh3(xdr, result->fh);
1759 	if (unlikely(error))
1760 		goto out;
1761 	error = decode_post_op_attr(xdr, result->fattr, userns);
1762 	if (unlikely(error))
1763 		goto out;
1764 	/* The server isn't required to return a file handle.
1765 	 * If it didn't, force the client to perform a LOOKUP
1766 	 * to determine the correct file handle and attribute
1767 	 * values for the new object. */
1768 	if (result->fh->size == 0)
1769 		result->fattr->valid = 0;
1770 	error = decode_wcc_data(xdr, result->dir_attr, userns);
1771 out:
1772 	return error;
1773 }
1774 
1775 static int nfs3_xdr_dec_create3res(struct rpc_rqst *req,
1776 				   struct xdr_stream *xdr,
1777 				   void *data)
1778 {
1779 	struct user_namespace *userns = rpc_rqst_userns(req);
1780 	struct nfs3_diropres *result = data;
1781 	enum nfs_stat status;
1782 	int error;
1783 
1784 	error = decode_nfsstat3(xdr, &status);
1785 	if (unlikely(error))
1786 		goto out;
1787 	if (status != NFS3_OK)
1788 		goto out_default;
1789 	error = decode_create3resok(xdr, result, userns);
1790 out:
1791 	return error;
1792 out_default:
1793 	error = decode_wcc_data(xdr, result->dir_attr, userns);
1794 	if (unlikely(error))
1795 		goto out;
1796 	return nfs3_stat_to_errno(status);
1797 }
1798 
1799 /*
1800  * 3.3.12  REMOVE3res
1801  *
1802  *	struct REMOVE3resok {
1803  *		wcc_data    dir_wcc;
1804  *	};
1805  *
1806  *	struct REMOVE3resfail {
1807  *		wcc_data    dir_wcc;
1808  *	};
1809  *
1810  *	union REMOVE3res switch (nfsstat3 status) {
1811  *	case NFS3_OK:
1812  *		REMOVE3resok   resok;
1813  *	default:
1814  *		REMOVE3resfail resfail;
1815  *	};
1816  */
1817 static int nfs3_xdr_dec_remove3res(struct rpc_rqst *req,
1818 				   struct xdr_stream *xdr,
1819 				   void *data)
1820 {
1821 	struct nfs_removeres *result = data;
1822 	enum nfs_stat status;
1823 	int error;
1824 
1825 	error = decode_nfsstat3(xdr, &status);
1826 	if (unlikely(error))
1827 		goto out;
1828 	error = decode_wcc_data(xdr, result->dir_attr, rpc_rqst_userns(req));
1829 	if (unlikely(error))
1830 		goto out;
1831 	if (status != NFS3_OK)
1832 		goto out_status;
1833 out:
1834 	return error;
1835 out_status:
1836 	return nfs3_stat_to_errno(status);
1837 }
1838 
1839 /*
1840  * 3.3.14  RENAME3res
1841  *
1842  *	struct RENAME3resok {
1843  *		wcc_data	fromdir_wcc;
1844  *		wcc_data	todir_wcc;
1845  *	};
1846  *
1847  *	struct RENAME3resfail {
1848  *		wcc_data	fromdir_wcc;
1849  *		wcc_data	todir_wcc;
1850  *	};
1851  *
1852  *	union RENAME3res switch (nfsstat3 status) {
1853  *	case NFS3_OK:
1854  *		RENAME3resok   resok;
1855  *	default:
1856  *		RENAME3resfail resfail;
1857  *	};
1858  */
1859 static int nfs3_xdr_dec_rename3res(struct rpc_rqst *req,
1860 				   struct xdr_stream *xdr,
1861 				   void *data)
1862 {
1863 	struct user_namespace *userns = rpc_rqst_userns(req);
1864 	struct nfs_renameres *result = data;
1865 	enum nfs_stat status;
1866 	int error;
1867 
1868 	error = decode_nfsstat3(xdr, &status);
1869 	if (unlikely(error))
1870 		goto out;
1871 	error = decode_wcc_data(xdr, result->old_fattr, userns);
1872 	if (unlikely(error))
1873 		goto out;
1874 	error = decode_wcc_data(xdr, result->new_fattr, userns);
1875 	if (unlikely(error))
1876 		goto out;
1877 	if (status != NFS3_OK)
1878 		goto out_status;
1879 out:
1880 	return error;
1881 out_status:
1882 	return nfs3_stat_to_errno(status);
1883 }
1884 
1885 /*
1886  * 3.3.15  LINK3res
1887  *
1888  *	struct LINK3resok {
1889  *		post_op_attr	file_attributes;
1890  *		wcc_data	linkdir_wcc;
1891  *	};
1892  *
1893  *	struct LINK3resfail {
1894  *		post_op_attr	file_attributes;
1895  *		wcc_data	linkdir_wcc;
1896  *	};
1897  *
1898  *	union LINK3res switch (nfsstat3 status) {
1899  *	case NFS3_OK:
1900  *		LINK3resok	resok;
1901  *	default:
1902  *		LINK3resfail	resfail;
1903  *	};
1904  */
1905 static int nfs3_xdr_dec_link3res(struct rpc_rqst *req, struct xdr_stream *xdr,
1906 				 void *data)
1907 {
1908 	struct user_namespace *userns = rpc_rqst_userns(req);
1909 	struct nfs3_linkres *result = data;
1910 	enum nfs_stat status;
1911 	int error;
1912 
1913 	error = decode_nfsstat3(xdr, &status);
1914 	if (unlikely(error))
1915 		goto out;
1916 	error = decode_post_op_attr(xdr, result->fattr, userns);
1917 	if (unlikely(error))
1918 		goto out;
1919 	error = decode_wcc_data(xdr, result->dir_attr, userns);
1920 	if (unlikely(error))
1921 		goto out;
1922 	if (status != NFS3_OK)
1923 		goto out_status;
1924 out:
1925 	return error;
1926 out_status:
1927 	return nfs3_stat_to_errno(status);
1928 }
1929 
1930 /**
1931  * nfs3_decode_dirent - Decode a single NFSv3 directory entry stored in
1932  *			the local page cache
1933  * @xdr: XDR stream where entry resides
1934  * @entry: buffer to fill in with entry data
1935  * @plus: boolean indicating whether this should be a readdirplus entry
1936  *
1937  * Returns zero if successful, otherwise a negative errno value is
1938  * returned.
1939  *
1940  * This function is not invoked during READDIR reply decoding, but
1941  * rather whenever an application invokes the getdents(2) system call
1942  * on a directory already in our cache.
1943  *
1944  * 3.3.16  entry3
1945  *
1946  *	struct entry3 {
1947  *		fileid3		fileid;
1948  *		filename3	name;
1949  *		cookie3		cookie;
1950  *		fhandle3	filehandle;
1951  *		post_op_attr3	attributes;
1952  *		entry3		*nextentry;
1953  *	};
1954  *
1955  * 3.3.17  entryplus3
1956  *	struct entryplus3 {
1957  *		fileid3		fileid;
1958  *		filename3	name;
1959  *		cookie3		cookie;
1960  *		post_op_attr	name_attributes;
1961  *		post_op_fh3	name_handle;
1962  *		entryplus3	*nextentry;
1963  *	};
1964  */
1965 int nfs3_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry,
1966 		       bool plus)
1967 {
1968 	struct user_namespace *userns = rpc_userns(entry->server->client);
1969 	struct nfs_entry old = *entry;
1970 	__be32 *p;
1971 	int error;
1972 	u64 new_cookie;
1973 
1974 	p = xdr_inline_decode(xdr, 4);
1975 	if (unlikely(!p))
1976 		return -EAGAIN;
1977 	if (*p == xdr_zero) {
1978 		p = xdr_inline_decode(xdr, 4);
1979 		if (unlikely(!p))
1980 			return -EAGAIN;
1981 		if (*p == xdr_zero)
1982 			return -EAGAIN;
1983 		entry->eof = 1;
1984 		return -EBADCOOKIE;
1985 	}
1986 
1987 	error = decode_fileid3(xdr, &entry->ino);
1988 	if (unlikely(error))
1989 		return error;
1990 
1991 	error = decode_inline_filename3(xdr, &entry->name, &entry->len);
1992 	if (unlikely(error))
1993 		return error;
1994 
1995 	error = decode_cookie3(xdr, &new_cookie);
1996 	if (unlikely(error))
1997 		return error;
1998 
1999 	entry->d_type = DT_UNKNOWN;
2000 
2001 	if (plus) {
2002 		entry->fattr->valid = 0;
2003 		error = decode_post_op_attr(xdr, entry->fattr, userns);
2004 		if (unlikely(error))
2005 			return error;
2006 		if (entry->fattr->valid & NFS_ATTR_FATTR_V3)
2007 			entry->d_type = nfs_umode_to_dtype(entry->fattr->mode);
2008 
2009 		if (entry->fattr->fileid != entry->ino) {
2010 			entry->fattr->mounted_on_fileid = entry->ino;
2011 			entry->fattr->valid |= NFS_ATTR_FATTR_MOUNTED_ON_FILEID;
2012 		}
2013 
2014 		/* In fact, a post_op_fh3: */
2015 		p = xdr_inline_decode(xdr, 4);
2016 		if (unlikely(!p))
2017 			return -EAGAIN;
2018 		if (*p != xdr_zero) {
2019 			error = decode_nfs_fh3(xdr, entry->fh);
2020 			if (unlikely(error)) {
2021 				if (error == -E2BIG)
2022 					goto out_truncated;
2023 				return error;
2024 			}
2025 		} else
2026 			zero_nfs_fh3(entry->fh);
2027 	}
2028 
2029 	entry->prev_cookie = entry->cookie;
2030 	entry->cookie = new_cookie;
2031 
2032 	return 0;
2033 
2034 out_truncated:
2035 	dprintk("NFS: directory entry contains invalid file handle\n");
2036 	*entry = old;
2037 	return -EAGAIN;
2038 }
2039 
2040 /*
2041  * 3.3.16  READDIR3res
2042  *
2043  *	struct dirlist3 {
2044  *		entry3		*entries;
2045  *		bool		eof;
2046  *	};
2047  *
2048  *	struct READDIR3resok {
2049  *		post_op_attr	dir_attributes;
2050  *		cookieverf3	cookieverf;
2051  *		dirlist3	reply;
2052  *	};
2053  *
2054  *	struct READDIR3resfail {
2055  *		post_op_attr	dir_attributes;
2056  *	};
2057  *
2058  *	union READDIR3res switch (nfsstat3 status) {
2059  *	case NFS3_OK:
2060  *		READDIR3resok	resok;
2061  *	default:
2062  *		READDIR3resfail	resfail;
2063  *	};
2064  *
2065  * Read the directory contents into the page cache, but otherwise
2066  * don't touch them.  The actual decoding is done by nfs3_decode_entry()
2067  * during subsequent nfs_readdir() calls.
2068  */
2069 static int decode_dirlist3(struct xdr_stream *xdr)
2070 {
2071 	return xdr_read_pages(xdr, xdr->buf->page_len);
2072 }
2073 
2074 static int decode_readdir3resok(struct xdr_stream *xdr,
2075 				struct nfs3_readdirres *result,
2076 				struct user_namespace *userns)
2077 {
2078 	int error;
2079 
2080 	error = decode_post_op_attr(xdr, result->dir_attr, userns);
2081 	if (unlikely(error))
2082 		goto out;
2083 	/* XXX: do we need to check if result->verf != NULL ? */
2084 	error = decode_cookieverf3(xdr, result->verf);
2085 	if (unlikely(error))
2086 		goto out;
2087 	error = decode_dirlist3(xdr);
2088 out:
2089 	return error;
2090 }
2091 
2092 static int nfs3_xdr_dec_readdir3res(struct rpc_rqst *req,
2093 				    struct xdr_stream *xdr,
2094 				    void *data)
2095 {
2096 	struct nfs3_readdirres *result = data;
2097 	enum nfs_stat status;
2098 	int error;
2099 
2100 	error = decode_nfsstat3(xdr, &status);
2101 	if (unlikely(error))
2102 		goto out;
2103 	if (status != NFS3_OK)
2104 		goto out_default;
2105 	error = decode_readdir3resok(xdr, result, rpc_rqst_userns(req));
2106 out:
2107 	return error;
2108 out_default:
2109 	error = decode_post_op_attr(xdr, result->dir_attr, rpc_rqst_userns(req));
2110 	if (unlikely(error))
2111 		goto out;
2112 	return nfs3_stat_to_errno(status);
2113 }
2114 
2115 /*
2116  * 3.3.18  FSSTAT3res
2117  *
2118  *	struct FSSTAT3resok {
2119  *		post_op_attr	obj_attributes;
2120  *		size3		tbytes;
2121  *		size3		fbytes;
2122  *		size3		abytes;
2123  *		size3		tfiles;
2124  *		size3		ffiles;
2125  *		size3		afiles;
2126  *		uint32		invarsec;
2127  *	};
2128  *
2129  *	struct FSSTAT3resfail {
2130  *		post_op_attr	obj_attributes;
2131  *	};
2132  *
2133  *	union FSSTAT3res switch (nfsstat3 status) {
2134  *	case NFS3_OK:
2135  *		FSSTAT3resok	resok;
2136  *	default:
2137  *		FSSTAT3resfail	resfail;
2138  *	};
2139  */
2140 static int decode_fsstat3resok(struct xdr_stream *xdr,
2141 			       struct nfs_fsstat *result)
2142 {
2143 	__be32 *p;
2144 
2145 	p = xdr_inline_decode(xdr, 8 * 6 + 4);
2146 	if (unlikely(!p))
2147 		return -EIO;
2148 	p = xdr_decode_size3(p, &result->tbytes);
2149 	p = xdr_decode_size3(p, &result->fbytes);
2150 	p = xdr_decode_size3(p, &result->abytes);
2151 	p = xdr_decode_size3(p, &result->tfiles);
2152 	p = xdr_decode_size3(p, &result->ffiles);
2153 	xdr_decode_size3(p, &result->afiles);
2154 	/* ignore invarsec */
2155 	return 0;
2156 }
2157 
2158 static int nfs3_xdr_dec_fsstat3res(struct rpc_rqst *req,
2159 				   struct xdr_stream *xdr,
2160 				   void *data)
2161 {
2162 	struct nfs_fsstat *result = data;
2163 	enum nfs_stat status;
2164 	int error;
2165 
2166 	error = decode_nfsstat3(xdr, &status);
2167 	if (unlikely(error))
2168 		goto out;
2169 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
2170 	if (unlikely(error))
2171 		goto out;
2172 	if (status != NFS3_OK)
2173 		goto out_status;
2174 	error = decode_fsstat3resok(xdr, result);
2175 out:
2176 	return error;
2177 out_status:
2178 	return nfs3_stat_to_errno(status);
2179 }
2180 
2181 /*
2182  * 3.3.19  FSINFO3res
2183  *
2184  *	struct FSINFO3resok {
2185  *		post_op_attr	obj_attributes;
2186  *		uint32		rtmax;
2187  *		uint32		rtpref;
2188  *		uint32		rtmult;
2189  *		uint32		wtmax;
2190  *		uint32		wtpref;
2191  *		uint32		wtmult;
2192  *		uint32		dtpref;
2193  *		size3		maxfilesize;
2194  *		nfstime3	time_delta;
2195  *		uint32		properties;
2196  *	};
2197  *
2198  *	struct FSINFO3resfail {
2199  *		post_op_attr	obj_attributes;
2200  *	};
2201  *
2202  *	union FSINFO3res switch (nfsstat3 status) {
2203  *	case NFS3_OK:
2204  *		FSINFO3resok	resok;
2205  *	default:
2206  *		FSINFO3resfail	resfail;
2207  *	};
2208  */
2209 static int decode_fsinfo3resok(struct xdr_stream *xdr,
2210 			       struct nfs_fsinfo *result)
2211 {
2212 	__be32 *p;
2213 
2214 	p = xdr_inline_decode(xdr, 4 * 7 + 8 + 8 + 4);
2215 	if (unlikely(!p))
2216 		return -EIO;
2217 	result->rtmax  = be32_to_cpup(p++);
2218 	result->rtpref = be32_to_cpup(p++);
2219 	result->rtmult = be32_to_cpup(p++);
2220 	result->wtmax  = be32_to_cpup(p++);
2221 	result->wtpref = be32_to_cpup(p++);
2222 	result->wtmult = be32_to_cpup(p++);
2223 	result->dtpref = be32_to_cpup(p++);
2224 	p = xdr_decode_size3(p, &result->maxfilesize);
2225 	xdr_decode_nfstime3(p, &result->time_delta);
2226 
2227 	/* ignore properties */
2228 	result->lease_time = 0;
2229 	return 0;
2230 }
2231 
2232 static int nfs3_xdr_dec_fsinfo3res(struct rpc_rqst *req,
2233 				   struct xdr_stream *xdr,
2234 				   void *data)
2235 {
2236 	struct nfs_fsinfo *result = data;
2237 	enum nfs_stat status;
2238 	int error;
2239 
2240 	error = decode_nfsstat3(xdr, &status);
2241 	if (unlikely(error))
2242 		goto out;
2243 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
2244 	if (unlikely(error))
2245 		goto out;
2246 	if (status != NFS3_OK)
2247 		goto out_status;
2248 	error = decode_fsinfo3resok(xdr, result);
2249 out:
2250 	return error;
2251 out_status:
2252 	return nfs3_stat_to_errno(status);
2253 }
2254 
2255 /*
2256  * 3.3.20  PATHCONF3res
2257  *
2258  *	struct PATHCONF3resok {
2259  *		post_op_attr	obj_attributes;
2260  *		uint32		linkmax;
2261  *		uint32		name_max;
2262  *		bool		no_trunc;
2263  *		bool		chown_restricted;
2264  *		bool		case_insensitive;
2265  *		bool		case_preserving;
2266  *	};
2267  *
2268  *	struct PATHCONF3resfail {
2269  *		post_op_attr	obj_attributes;
2270  *	};
2271  *
2272  *	union PATHCONF3res switch (nfsstat3 status) {
2273  *	case NFS3_OK:
2274  *		PATHCONF3resok	resok;
2275  *	default:
2276  *		PATHCONF3resfail resfail;
2277  *	};
2278  */
2279 static int decode_pathconf3resok(struct xdr_stream *xdr,
2280 				 struct nfs_pathconf *result)
2281 {
2282 	__be32 *p;
2283 
2284 	p = xdr_inline_decode(xdr, 4 * 6);
2285 	if (unlikely(!p))
2286 		return -EIO;
2287 	result->max_link = be32_to_cpup(p++);
2288 	result->max_namelen = be32_to_cpup(p);
2289 	/* ignore remaining fields */
2290 	return 0;
2291 }
2292 
2293 static int nfs3_xdr_dec_pathconf3res(struct rpc_rqst *req,
2294 				     struct xdr_stream *xdr,
2295 				     void *data)
2296 {
2297 	struct nfs_pathconf *result = data;
2298 	enum nfs_stat status;
2299 	int error;
2300 
2301 	error = decode_nfsstat3(xdr, &status);
2302 	if (unlikely(error))
2303 		goto out;
2304 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
2305 	if (unlikely(error))
2306 		goto out;
2307 	if (status != NFS3_OK)
2308 		goto out_status;
2309 	error = decode_pathconf3resok(xdr, result);
2310 out:
2311 	return error;
2312 out_status:
2313 	return nfs3_stat_to_errno(status);
2314 }
2315 
2316 /*
2317  * 3.3.21  COMMIT3res
2318  *
2319  *	struct COMMIT3resok {
2320  *		wcc_data	file_wcc;
2321  *		writeverf3	verf;
2322  *	};
2323  *
2324  *	struct COMMIT3resfail {
2325  *		wcc_data	file_wcc;
2326  *	};
2327  *
2328  *	union COMMIT3res switch (nfsstat3 status) {
2329  *	case NFS3_OK:
2330  *		COMMIT3resok	resok;
2331  *	default:
2332  *		COMMIT3resfail	resfail;
2333  *	};
2334  */
2335 static int nfs3_xdr_dec_commit3res(struct rpc_rqst *req,
2336 				   struct xdr_stream *xdr,
2337 				   void *data)
2338 {
2339 	struct nfs_commitres *result = data;
2340 	struct nfs_writeverf *verf = result->verf;
2341 	enum nfs_stat status;
2342 	int error;
2343 
2344 	error = decode_nfsstat3(xdr, &status);
2345 	if (unlikely(error))
2346 		goto out;
2347 	error = decode_wcc_data(xdr, result->fattr, rpc_rqst_userns(req));
2348 	if (unlikely(error))
2349 		goto out;
2350 	result->op_status = status;
2351 	if (status != NFS3_OK)
2352 		goto out_status;
2353 	error = decode_writeverf3(xdr, &verf->verifier);
2354 	if (!error)
2355 		verf->committed = NFS_FILE_SYNC;
2356 out:
2357 	return error;
2358 out_status:
2359 	return nfs3_stat_to_errno(status);
2360 }
2361 
2362 #ifdef CONFIG_NFS_V3_ACL
2363 
2364 static inline int decode_getacl3resok(struct xdr_stream *xdr,
2365 				      struct nfs3_getaclres *result,
2366 				      struct user_namespace *userns)
2367 {
2368 	struct posix_acl **acl;
2369 	unsigned int *aclcnt;
2370 	size_t hdrlen;
2371 	int error;
2372 
2373 	error = decode_post_op_attr(xdr, result->fattr, userns);
2374 	if (unlikely(error))
2375 		goto out;
2376 	error = decode_uint32(xdr, &result->mask);
2377 	if (unlikely(error))
2378 		goto out;
2379 	error = -EINVAL;
2380 	if (result->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT))
2381 		goto out;
2382 
2383 	hdrlen = xdr_stream_pos(xdr);
2384 
2385 	acl = NULL;
2386 	if (result->mask & NFS_ACL)
2387 		acl = &result->acl_access;
2388 	aclcnt = NULL;
2389 	if (result->mask & NFS_ACLCNT)
2390 		aclcnt = &result->acl_access_count;
2391 	error = nfsacl_decode(xdr->buf, hdrlen, aclcnt, acl);
2392 	if (unlikely(error <= 0))
2393 		goto out;
2394 
2395 	acl = NULL;
2396 	if (result->mask & NFS_DFACL)
2397 		acl = &result->acl_default;
2398 	aclcnt = NULL;
2399 	if (result->mask & NFS_DFACLCNT)
2400 		aclcnt = &result->acl_default_count;
2401 	error = nfsacl_decode(xdr->buf, hdrlen + error, aclcnt, acl);
2402 	if (unlikely(error <= 0))
2403 		return error;
2404 	error = 0;
2405 out:
2406 	return error;
2407 }
2408 
2409 static int nfs3_xdr_dec_getacl3res(struct rpc_rqst *req,
2410 				   struct xdr_stream *xdr,
2411 				   void *result)
2412 {
2413 	enum nfs_stat status;
2414 	int error;
2415 
2416 	error = decode_nfsstat3(xdr, &status);
2417 	if (unlikely(error))
2418 		goto out;
2419 	if (status != NFS3_OK)
2420 		goto out_default;
2421 	error = decode_getacl3resok(xdr, result, rpc_rqst_userns(req));
2422 out:
2423 	return error;
2424 out_default:
2425 	return nfs3_stat_to_errno(status);
2426 }
2427 
2428 static int nfs3_xdr_dec_setacl3res(struct rpc_rqst *req,
2429 				   struct xdr_stream *xdr,
2430 				   void *result)
2431 {
2432 	enum nfs_stat status;
2433 	int error;
2434 
2435 	error = decode_nfsstat3(xdr, &status);
2436 	if (unlikely(error))
2437 		goto out;
2438 	if (status != NFS3_OK)
2439 		goto out_default;
2440 	error = decode_post_op_attr(xdr, result, rpc_rqst_userns(req));
2441 out:
2442 	return error;
2443 out_default:
2444 	return nfs3_stat_to_errno(status);
2445 }
2446 
2447 #endif  /* CONFIG_NFS_V3_ACL */
2448 
2449 
2450 /*
2451  * We need to translate between nfs status return values and
2452  * the local errno values which may not be the same.
2453  */
2454 static const struct {
2455 	int stat;
2456 	int errno;
2457 } nfs_errtbl[] = {
2458 	{ NFS_OK,		0		},
2459 	{ NFSERR_PERM,		-EPERM		},
2460 	{ NFSERR_NOENT,		-ENOENT		},
2461 	{ NFSERR_IO,		-errno_NFSERR_IO},
2462 	{ NFSERR_NXIO,		-ENXIO		},
2463 /*	{ NFSERR_EAGAIN,	-EAGAIN		}, */
2464 	{ NFSERR_ACCES,		-EACCES		},
2465 	{ NFSERR_EXIST,		-EEXIST		},
2466 	{ NFSERR_XDEV,		-EXDEV		},
2467 	{ NFSERR_NODEV,		-ENODEV		},
2468 	{ NFSERR_NOTDIR,	-ENOTDIR	},
2469 	{ NFSERR_ISDIR,		-EISDIR		},
2470 	{ NFSERR_INVAL,		-EINVAL		},
2471 	{ NFSERR_FBIG,		-EFBIG		},
2472 	{ NFSERR_NOSPC,		-ENOSPC		},
2473 	{ NFSERR_ROFS,		-EROFS		},
2474 	{ NFSERR_MLINK,		-EMLINK		},
2475 	{ NFSERR_NAMETOOLONG,	-ENAMETOOLONG	},
2476 	{ NFSERR_NOTEMPTY,	-ENOTEMPTY	},
2477 	{ NFSERR_DQUOT,		-EDQUOT		},
2478 	{ NFSERR_STALE,		-ESTALE		},
2479 	{ NFSERR_REMOTE,	-EREMOTE	},
2480 #ifdef EWFLUSH
2481 	{ NFSERR_WFLUSH,	-EWFLUSH	},
2482 #endif
2483 	{ NFSERR_BADHANDLE,	-EBADHANDLE	},
2484 	{ NFSERR_NOT_SYNC,	-ENOTSYNC	},
2485 	{ NFSERR_BAD_COOKIE,	-EBADCOOKIE	},
2486 	{ NFSERR_NOTSUPP,	-ENOTSUPP	},
2487 	{ NFSERR_TOOSMALL,	-ETOOSMALL	},
2488 	{ NFSERR_SERVERFAULT,	-EREMOTEIO	},
2489 	{ NFSERR_BADTYPE,	-EBADTYPE	},
2490 	{ NFSERR_JUKEBOX,	-EJUKEBOX	},
2491 	{ -1,			-EIO		}
2492 };
2493 
2494 /**
2495  * nfs3_stat_to_errno - convert an NFS status code to a local errno
2496  * @status: NFS status code to convert
2497  *
2498  * Returns a local errno value, or -EIO if the NFS status code is
2499  * not recognized.  This function is used jointly by NFSv2 and NFSv3.
2500  */
2501 static int nfs3_stat_to_errno(enum nfs_stat status)
2502 {
2503 	int i;
2504 
2505 	for (i = 0; nfs_errtbl[i].stat != -1; i++) {
2506 		if (nfs_errtbl[i].stat == (int)status)
2507 			return nfs_errtbl[i].errno;
2508 	}
2509 	dprintk("NFS: Unrecognized nfs status value: %u\n", status);
2510 	return nfs_errtbl[i].errno;
2511 }
2512 
2513 
2514 #define PROC(proc, argtype, restype, timer)				\
2515 [NFS3PROC_##proc] = {							\
2516 	.p_proc      = NFS3PROC_##proc,					\
2517 	.p_encode    = nfs3_xdr_enc_##argtype##3args,			\
2518 	.p_decode    = nfs3_xdr_dec_##restype##3res,			\
2519 	.p_arglen    = NFS3_##argtype##args_sz,				\
2520 	.p_replen    = NFS3_##restype##res_sz,				\
2521 	.p_timer     = timer,						\
2522 	.p_statidx   = NFS3PROC_##proc,					\
2523 	.p_name      = #proc,						\
2524 	}
2525 
2526 const struct rpc_procinfo nfs3_procedures[] = {
2527 	PROC(GETATTR,		getattr,	getattr,	1),
2528 	PROC(SETATTR,		setattr,	setattr,	0),
2529 	PROC(LOOKUP,		lookup,		lookup,		2),
2530 	PROC(ACCESS,		access,		access,		1),
2531 	PROC(READLINK,		readlink,	readlink,	3),
2532 	PROC(READ,		read,		read,		3),
2533 	PROC(WRITE,		write,		write,		4),
2534 	PROC(CREATE,		create,		create,		0),
2535 	PROC(MKDIR,		mkdir,		create,		0),
2536 	PROC(SYMLINK,		symlink,	create,		0),
2537 	PROC(MKNOD,		mknod,		create,		0),
2538 	PROC(REMOVE,		remove,		remove,		0),
2539 	PROC(RMDIR,		lookup,		setattr,	0),
2540 	PROC(RENAME,		rename,		rename,		0),
2541 	PROC(LINK,		link,		link,		0),
2542 	PROC(READDIR,		readdir,	readdir,	3),
2543 	PROC(READDIRPLUS,	readdirplus,	readdir,	3),
2544 	PROC(FSSTAT,		getattr,	fsstat,		0),
2545 	PROC(FSINFO,		getattr,	fsinfo,		0),
2546 	PROC(PATHCONF,		getattr,	pathconf,	0),
2547 	PROC(COMMIT,		commit,		commit,		5),
2548 };
2549 
2550 static unsigned int nfs_version3_counts[ARRAY_SIZE(nfs3_procedures)];
2551 const struct rpc_version nfs_version3 = {
2552 	.number			= 3,
2553 	.nrprocs		= ARRAY_SIZE(nfs3_procedures),
2554 	.procs			= nfs3_procedures,
2555 	.counts			= nfs_version3_counts,
2556 };
2557 
2558 #ifdef CONFIG_NFS_V3_ACL
2559 static const struct rpc_procinfo nfs3_acl_procedures[] = {
2560 	[ACLPROC3_GETACL] = {
2561 		.p_proc = ACLPROC3_GETACL,
2562 		.p_encode = nfs3_xdr_enc_getacl3args,
2563 		.p_decode = nfs3_xdr_dec_getacl3res,
2564 		.p_arglen = ACL3_getaclargs_sz,
2565 		.p_replen = ACL3_getaclres_sz,
2566 		.p_timer = 1,
2567 		.p_name = "GETACL",
2568 	},
2569 	[ACLPROC3_SETACL] = {
2570 		.p_proc = ACLPROC3_SETACL,
2571 		.p_encode = nfs3_xdr_enc_setacl3args,
2572 		.p_decode = nfs3_xdr_dec_setacl3res,
2573 		.p_arglen = ACL3_setaclargs_sz,
2574 		.p_replen = ACL3_setaclres_sz,
2575 		.p_timer = 0,
2576 		.p_name = "SETACL",
2577 	},
2578 };
2579 
2580 static unsigned int nfs3_acl_counts[ARRAY_SIZE(nfs3_acl_procedures)];
2581 const struct rpc_version nfsacl_version3 = {
2582 	.number			= 3,
2583 	.nrprocs		= ARRAY_SIZE(nfs3_acl_procedures),
2584 	.procs			= nfs3_acl_procedures,
2585 	.counts			= nfs3_acl_counts,
2586 };
2587 #endif  /* CONFIG_NFS_V3_ACL */
2588