xref: /openbmc/linux/fs/nfs/nfs3xdr.c (revision 63705da3)
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_post_op_fh_sz	(1+NFS3_fh_sz)
40 #define NFS3_sattr_sz		(15)
41 #define NFS3_filename_sz	(1+(NFS3_MAXNAMLEN>>2))
42 #define NFS3_path_sz		(1+(NFS3_MAXPATHLEN>>2))
43 #define NFS3_fattr_sz		(21)
44 #define NFS3_cookieverf_sz	(NFS3_COOKIEVERFSIZE>>2)
45 #define NFS3_wcc_attr_sz	(6)
46 #define NFS3_pre_op_attr_sz	(1+NFS3_wcc_attr_sz)
47 #define NFS3_post_op_attr_sz	(1+NFS3_fattr_sz)
48 #define NFS3_wcc_data_sz	(NFS3_pre_op_attr_sz+NFS3_post_op_attr_sz)
49 #define NFS3_diropargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
50 
51 #define NFS3_getattrargs_sz	(NFS3_fh_sz)
52 #define NFS3_setattrargs_sz	(NFS3_fh_sz+NFS3_sattr_sz+3)
53 #define NFS3_lookupargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
54 #define NFS3_accessargs_sz	(NFS3_fh_sz+1)
55 #define NFS3_readlinkargs_sz	(NFS3_fh_sz)
56 #define NFS3_readargs_sz	(NFS3_fh_sz+3)
57 #define NFS3_writeargs_sz	(NFS3_fh_sz+5)
58 #define NFS3_createargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
59 #define NFS3_mkdirargs_sz	(NFS3_diropargs_sz+NFS3_sattr_sz)
60 #define NFS3_symlinkargs_sz	(NFS3_diropargs_sz+1+NFS3_sattr_sz)
61 #define NFS3_mknodargs_sz	(NFS3_diropargs_sz+2+NFS3_sattr_sz)
62 #define NFS3_removeargs_sz	(NFS3_fh_sz+NFS3_filename_sz)
63 #define NFS3_renameargs_sz	(NFS3_diropargs_sz+NFS3_diropargs_sz)
64 #define NFS3_linkargs_sz		(NFS3_fh_sz+NFS3_diropargs_sz)
65 #define NFS3_readdirargs_sz	(NFS3_fh_sz+NFS3_cookieverf_sz+3)
66 #define NFS3_readdirplusargs_sz	(NFS3_fh_sz+NFS3_cookieverf_sz+4)
67 #define NFS3_commitargs_sz	(NFS3_fh_sz+3)
68 
69 #define NFS3_getattrres_sz	(1+NFS3_fattr_sz)
70 #define NFS3_setattrres_sz	(1+NFS3_wcc_data_sz)
71 #define NFS3_removeres_sz	(NFS3_setattrres_sz)
72 #define NFS3_lookupres_sz	(1+NFS3_fh_sz+(2 * NFS3_post_op_attr_sz))
73 #define NFS3_accessres_sz	(1+NFS3_post_op_attr_sz+1)
74 #define NFS3_readlinkres_sz	(1+NFS3_post_op_attr_sz+1+NFS3_pagepad_sz)
75 #define NFS3_readres_sz		(1+NFS3_post_op_attr_sz+3+NFS3_pagepad_sz)
76 #define NFS3_writeres_sz	(1+NFS3_wcc_data_sz+4)
77 #define NFS3_createres_sz	(1+NFS3_post_op_fh_sz+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
78 #define NFS3_renameres_sz	(1+(2 * NFS3_wcc_data_sz))
79 #define NFS3_linkres_sz		(1+NFS3_post_op_attr_sz+NFS3_wcc_data_sz)
80 #define NFS3_readdirres_sz	(1+NFS3_post_op_attr_sz+2+NFS3_pagepad_sz)
81 #define NFS3_fsstatres_sz	(1+NFS3_post_op_attr_sz+13)
82 #define NFS3_fsinfores_sz	(1+NFS3_post_op_attr_sz+12)
83 #define NFS3_pathconfres_sz	(1+NFS3_post_op_attr_sz+6)
84 #define NFS3_commitres_sz	(1+NFS3_wcc_data_sz+2)
85 
86 #define ACL3_getaclargs_sz	(NFS3_fh_sz+1)
87 #define ACL3_setaclargs_sz	(NFS3_fh_sz+1+ \
88 				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE))
89 #define ACL3_getaclres_sz	(1+NFS3_post_op_attr_sz+1+ \
90 				XDR_QUADLEN(NFS_ACL_INLINE_BUFSIZE)+\
91 				NFS3_pagepad_sz)
92 #define ACL3_setaclres_sz	(1+NFS3_post_op_attr_sz)
93 
94 static int nfs3_stat_to_errno(enum nfs_stat);
95 
96 /*
97  * Map file type to S_IFMT bits
98  */
99 static const umode_t nfs_type2fmt[] = {
100 	[NF3BAD] = 0,
101 	[NF3REG] = S_IFREG,
102 	[NF3DIR] = S_IFDIR,
103 	[NF3BLK] = S_IFBLK,
104 	[NF3CHR] = S_IFCHR,
105 	[NF3LNK] = S_IFLNK,
106 	[NF3SOCK] = S_IFSOCK,
107 	[NF3FIFO] = S_IFIFO,
108 };
109 
110 static struct user_namespace *rpc_userns(const struct rpc_clnt *clnt)
111 {
112 	if (clnt && clnt->cl_cred)
113 		return clnt->cl_cred->user_ns;
114 	return &init_user_ns;
115 }
116 
117 static struct user_namespace *rpc_rqst_userns(const struct rpc_rqst *rqstp)
118 {
119 	if (rqstp->rq_task)
120 		return rpc_userns(rqstp->rq_task->tk_client);
121 	return &init_user_ns;
122 }
123 
124 /*
125  * Encode/decode NFSv3 basic data types
126  *
127  * Basic NFSv3 data types are defined in section 2.5 of RFC 1813:
128  * "NFS Version 3 Protocol Specification".
129  *
130  * Not all basic data types have their own encoding and decoding
131  * functions.  For run-time efficiency, some data types are encoded
132  * or decoded inline.
133  */
134 
135 static void encode_uint32(struct xdr_stream *xdr, u32 value)
136 {
137 	__be32 *p = xdr_reserve_space(xdr, 4);
138 	*p = cpu_to_be32(value);
139 }
140 
141 static int decode_uint32(struct xdr_stream *xdr, u32 *value)
142 {
143 	__be32 *p;
144 
145 	p = xdr_inline_decode(xdr, 4);
146 	if (unlikely(!p))
147 		return -EIO;
148 	*value = be32_to_cpup(p);
149 	return 0;
150 }
151 
152 static int decode_uint64(struct xdr_stream *xdr, u64 *value)
153 {
154 	__be32 *p;
155 
156 	p = xdr_inline_decode(xdr, 8);
157 	if (unlikely(!p))
158 		return -EIO;
159 	xdr_decode_hyper(p, value);
160 	return 0;
161 }
162 
163 /*
164  * fileid3
165  *
166  *	typedef uint64 fileid3;
167  */
168 static __be32 *xdr_decode_fileid3(__be32 *p, u64 *fileid)
169 {
170 	return xdr_decode_hyper(p, fileid);
171 }
172 
173 static int decode_fileid3(struct xdr_stream *xdr, u64 *fileid)
174 {
175 	return decode_uint64(xdr, fileid);
176 }
177 
178 /*
179  * filename3
180  *
181  *	typedef string filename3<>;
182  */
183 static void encode_filename3(struct xdr_stream *xdr,
184 			     const char *name, u32 length)
185 {
186 	__be32 *p;
187 
188 	WARN_ON_ONCE(length > NFS3_MAXNAMLEN);
189 	p = xdr_reserve_space(xdr, 4 + length);
190 	xdr_encode_opaque(p, name, length);
191 }
192 
193 static int decode_inline_filename3(struct xdr_stream *xdr,
194 				   const char **name, u32 *length)
195 {
196 	__be32 *p;
197 	u32 count;
198 
199 	p = xdr_inline_decode(xdr, 4);
200 	if (unlikely(!p))
201 		return -EIO;
202 	count = be32_to_cpup(p);
203 	if (count > NFS3_MAXNAMLEN)
204 		goto out_nametoolong;
205 	p = xdr_inline_decode(xdr, count);
206 	if (unlikely(!p))
207 		return -EIO;
208 	*name = (const char *)p;
209 	*length = count;
210 	return 0;
211 
212 out_nametoolong:
213 	dprintk("NFS: returned filename too long: %u\n", count);
214 	return -ENAMETOOLONG;
215 }
216 
217 /*
218  * nfspath3
219  *
220  *	typedef string nfspath3<>;
221  */
222 static void encode_nfspath3(struct xdr_stream *xdr, struct page **pages,
223 			    const u32 length)
224 {
225 	encode_uint32(xdr, length);
226 	xdr_write_pages(xdr, pages, 0, length);
227 }
228 
229 static int decode_nfspath3(struct xdr_stream *xdr)
230 {
231 	u32 recvd, count;
232 	__be32 *p;
233 
234 	p = xdr_inline_decode(xdr, 4);
235 	if (unlikely(!p))
236 		return -EIO;
237 	count = be32_to_cpup(p);
238 	if (unlikely(count >= xdr->buf->page_len || count > NFS3_MAXPATHLEN))
239 		goto out_nametoolong;
240 	recvd = xdr_read_pages(xdr, count);
241 	if (unlikely(count > recvd))
242 		goto out_cheating;
243 	xdr_terminate_string(xdr->buf, count);
244 	return 0;
245 
246 out_nametoolong:
247 	dprintk("NFS: returned pathname too long: %u\n", count);
248 	return -ENAMETOOLONG;
249 out_cheating:
250 	dprintk("NFS: server cheating in pathname result: "
251 		"count %u > recvd %u\n", count, recvd);
252 	return -EIO;
253 }
254 
255 /*
256  * cookie3
257  *
258  *	typedef uint64 cookie3
259  */
260 static __be32 *xdr_encode_cookie3(__be32 *p, u64 cookie)
261 {
262 	return xdr_encode_hyper(p, cookie);
263 }
264 
265 static int decode_cookie3(struct xdr_stream *xdr, u64 *cookie)
266 {
267 	return decode_uint64(xdr, cookie);
268 }
269 
270 /*
271  * cookieverf3
272  *
273  *	typedef opaque cookieverf3[NFS3_COOKIEVERFSIZE];
274  */
275 static __be32 *xdr_encode_cookieverf3(__be32 *p, const __be32 *verifier)
276 {
277 	memcpy(p, verifier, NFS3_COOKIEVERFSIZE);
278 	return p + XDR_QUADLEN(NFS3_COOKIEVERFSIZE);
279 }
280 
281 static int decode_cookieverf3(struct xdr_stream *xdr, __be32 *verifier)
282 {
283 	__be32 *p;
284 
285 	p = xdr_inline_decode(xdr, NFS3_COOKIEVERFSIZE);
286 	if (unlikely(!p))
287 		return -EIO;
288 	memcpy(verifier, p, NFS3_COOKIEVERFSIZE);
289 	return 0;
290 }
291 
292 /*
293  * createverf3
294  *
295  *	typedef opaque createverf3[NFS3_CREATEVERFSIZE];
296  */
297 static void encode_createverf3(struct xdr_stream *xdr, const __be32 *verifier)
298 {
299 	__be32 *p;
300 
301 	p = xdr_reserve_space(xdr, NFS3_CREATEVERFSIZE);
302 	memcpy(p, verifier, NFS3_CREATEVERFSIZE);
303 }
304 
305 static int decode_writeverf3(struct xdr_stream *xdr, struct nfs_write_verifier *verifier)
306 {
307 	__be32 *p;
308 
309 	p = xdr_inline_decode(xdr, NFS3_WRITEVERFSIZE);
310 	if (unlikely(!p))
311 		return -EIO;
312 	memcpy(verifier->data, p, NFS3_WRITEVERFSIZE);
313 	return 0;
314 }
315 
316 /*
317  * size3
318  *
319  *	typedef uint64 size3;
320  */
321 static __be32 *xdr_decode_size3(__be32 *p, u64 *size)
322 {
323 	return xdr_decode_hyper(p, size);
324 }
325 
326 /*
327  * nfsstat3
328  *
329  *	enum nfsstat3 {
330  *		NFS3_OK = 0,
331  *		...
332  *	}
333  */
334 #define NFS3_OK		NFS_OK
335 
336 static int decode_nfsstat3(struct xdr_stream *xdr, enum nfs_stat *status)
337 {
338 	__be32 *p;
339 
340 	p = xdr_inline_decode(xdr, 4);
341 	if (unlikely(!p))
342 		return -EIO;
343 	if (unlikely(*p != cpu_to_be32(NFS3_OK)))
344 		goto out_status;
345 	*status = 0;
346 	return 0;
347 out_status:
348 	*status = be32_to_cpup(p);
349 	trace_nfs_xdr_status(xdr, (int)*status);
350 	return 0;
351 }
352 
353 /*
354  * ftype3
355  *
356  *	enum ftype3 {
357  *		NF3REG	= 1,
358  *		NF3DIR	= 2,
359  *		NF3BLK	= 3,
360  *		NF3CHR	= 4,
361  *		NF3LNK	= 5,
362  *		NF3SOCK	= 6,
363  *		NF3FIFO	= 7
364  *	};
365  */
366 static void encode_ftype3(struct xdr_stream *xdr, const u32 type)
367 {
368 	encode_uint32(xdr, type);
369 }
370 
371 static __be32 *xdr_decode_ftype3(__be32 *p, umode_t *mode)
372 {
373 	u32 type;
374 
375 	type = be32_to_cpup(p++);
376 	if (type > NF3FIFO)
377 		type = NF3NON;
378 	*mode = nfs_type2fmt[type];
379 	return p;
380 }
381 
382 /*
383  * specdata3
384  *
385  *     struct specdata3 {
386  *             uint32  specdata1;
387  *             uint32  specdata2;
388  *     };
389  */
390 static void encode_specdata3(struct xdr_stream *xdr, const dev_t rdev)
391 {
392 	__be32 *p;
393 
394 	p = xdr_reserve_space(xdr, 8);
395 	*p++ = cpu_to_be32(MAJOR(rdev));
396 	*p = cpu_to_be32(MINOR(rdev));
397 }
398 
399 static __be32 *xdr_decode_specdata3(__be32 *p, dev_t *rdev)
400 {
401 	unsigned int major, minor;
402 
403 	major = be32_to_cpup(p++);
404 	minor = be32_to_cpup(p++);
405 	*rdev = MKDEV(major, minor);
406 	if (MAJOR(*rdev) != major || MINOR(*rdev) != minor)
407 		*rdev = 0;
408 	return p;
409 }
410 
411 /*
412  * nfs_fh3
413  *
414  *	struct nfs_fh3 {
415  *		opaque       data<NFS3_FHSIZE>;
416  *	};
417  */
418 static void encode_nfs_fh3(struct xdr_stream *xdr, const struct nfs_fh *fh)
419 {
420 	__be32 *p;
421 
422 	WARN_ON_ONCE(fh->size > NFS3_FHSIZE);
423 	p = xdr_reserve_space(xdr, 4 + fh->size);
424 	xdr_encode_opaque(p, fh->data, fh->size);
425 }
426 
427 static int decode_nfs_fh3(struct xdr_stream *xdr, struct nfs_fh *fh)
428 {
429 	u32 length;
430 	__be32 *p;
431 
432 	p = xdr_inline_decode(xdr, 4);
433 	if (unlikely(!p))
434 		return -EIO;
435 	length = be32_to_cpup(p++);
436 	if (unlikely(length > NFS3_FHSIZE || length == 0))
437 		goto out_toobig;
438 	p = xdr_inline_decode(xdr, length);
439 	if (unlikely(!p))
440 		return -EIO;
441 	fh->size = length;
442 	memcpy(fh->data, p, length);
443 	return 0;
444 out_toobig:
445 	trace_nfs_xdr_bad_filehandle(xdr, NFSERR_BADHANDLE);
446 	return -E2BIG;
447 }
448 
449 static void zero_nfs_fh3(struct nfs_fh *fh)
450 {
451 	memset(fh, 0, sizeof(*fh));
452 }
453 
454 /*
455  * nfstime3
456  *
457  *	struct nfstime3 {
458  *		uint32	seconds;
459  *		uint32	nseconds;
460  *	};
461  */
462 static __be32 *xdr_encode_nfstime3(__be32 *p, const struct timespec64 *timep)
463 {
464 	*p++ = cpu_to_be32((u32)timep->tv_sec);
465 	*p++ = cpu_to_be32(timep->tv_nsec);
466 	return p;
467 }
468 
469 static __be32 *xdr_decode_nfstime3(__be32 *p, struct timespec64 *timep)
470 {
471 	timep->tv_sec = be32_to_cpup(p++);
472 	timep->tv_nsec = be32_to_cpup(p++);
473 	return p;
474 }
475 
476 /*
477  * sattr3
478  *
479  *	enum time_how {
480  *		DONT_CHANGE		= 0,
481  *		SET_TO_SERVER_TIME	= 1,
482  *		SET_TO_CLIENT_TIME	= 2
483  *	};
484  *
485  *	union set_mode3 switch (bool set_it) {
486  *	case TRUE:
487  *		mode3	mode;
488  *	default:
489  *		void;
490  *	};
491  *
492  *	union set_uid3 switch (bool set_it) {
493  *	case TRUE:
494  *		uid3	uid;
495  *	default:
496  *		void;
497  *	};
498  *
499  *	union set_gid3 switch (bool set_it) {
500  *	case TRUE:
501  *		gid3	gid;
502  *	default:
503  *		void;
504  *	};
505  *
506  *	union set_size3 switch (bool set_it) {
507  *	case TRUE:
508  *		size3	size;
509  *	default:
510  *		void;
511  *	};
512  *
513  *	union set_atime switch (time_how set_it) {
514  *	case SET_TO_CLIENT_TIME:
515  *		nfstime3	atime;
516  *	default:
517  *		void;
518  *	};
519  *
520  *	union set_mtime switch (time_how set_it) {
521  *	case SET_TO_CLIENT_TIME:
522  *		nfstime3  mtime;
523  *	default:
524  *		void;
525  *	};
526  *
527  *	struct sattr3 {
528  *		set_mode3	mode;
529  *		set_uid3	uid;
530  *		set_gid3	gid;
531  *		set_size3	size;
532  *		set_atime	atime;
533  *		set_mtime	mtime;
534  *	};
535  */
536 static void encode_sattr3(struct xdr_stream *xdr, const struct iattr *attr,
537 		struct user_namespace *userns)
538 {
539 	u32 nbytes;
540 	__be32 *p;
541 
542 	/*
543 	 * In order to make only a single xdr_reserve_space() call,
544 	 * pre-compute the total number of bytes to be reserved.
545 	 * Six boolean values, one for each set_foo field, are always
546 	 * present in the encoded result, so start there.
547 	 */
548 	nbytes = 6 * 4;
549 	if (attr->ia_valid & ATTR_MODE)
550 		nbytes += 4;
551 	if (attr->ia_valid & ATTR_UID)
552 		nbytes += 4;
553 	if (attr->ia_valid & ATTR_GID)
554 		nbytes += 4;
555 	if (attr->ia_valid & ATTR_SIZE)
556 		nbytes += 8;
557 	if (attr->ia_valid & ATTR_ATIME_SET)
558 		nbytes += 8;
559 	if (attr->ia_valid & ATTR_MTIME_SET)
560 		nbytes += 8;
561 	p = xdr_reserve_space(xdr, nbytes);
562 
563 	if (attr->ia_valid & ATTR_MODE) {
564 		*p++ = xdr_one;
565 		*p++ = cpu_to_be32(attr->ia_mode & S_IALLUGO);
566 	} else
567 		*p++ = xdr_zero;
568 
569 	if (attr->ia_valid & ATTR_UID) {
570 		*p++ = xdr_one;
571 		*p++ = cpu_to_be32(from_kuid_munged(userns, attr->ia_uid));
572 	} else
573 		*p++ = xdr_zero;
574 
575 	if (attr->ia_valid & ATTR_GID) {
576 		*p++ = xdr_one;
577 		*p++ = cpu_to_be32(from_kgid_munged(userns, attr->ia_gid));
578 	} else
579 		*p++ = xdr_zero;
580 
581 	if (attr->ia_valid & ATTR_SIZE) {
582 		*p++ = xdr_one;
583 		p = xdr_encode_hyper(p, (u64)attr->ia_size);
584 	} else
585 		*p++ = xdr_zero;
586 
587 	if (attr->ia_valid & ATTR_ATIME_SET) {
588 		*p++ = xdr_two;
589 		p = xdr_encode_nfstime3(p, &attr->ia_atime);
590 	} else if (attr->ia_valid & ATTR_ATIME) {
591 		*p++ = xdr_one;
592 	} else
593 		*p++ = xdr_zero;
594 
595 	if (attr->ia_valid & ATTR_MTIME_SET) {
596 		*p++ = xdr_two;
597 		xdr_encode_nfstime3(p, &attr->ia_mtime);
598 	} else if (attr->ia_valid & ATTR_MTIME) {
599 		*p = xdr_one;
600 	} else
601 		*p = xdr_zero;
602 }
603 
604 /*
605  * fattr3
606  *
607  *	struct fattr3 {
608  *		ftype3		type;
609  *		mode3		mode;
610  *		uint32		nlink;
611  *		uid3		uid;
612  *		gid3		gid;
613  *		size3		size;
614  *		size3		used;
615  *		specdata3	rdev;
616  *		uint64		fsid;
617  *		fileid3		fileid;
618  *		nfstime3	atime;
619  *		nfstime3	mtime;
620  *		nfstime3	ctime;
621  *	};
622  */
623 static int decode_fattr3(struct xdr_stream *xdr, struct nfs_fattr *fattr,
624 		struct user_namespace *userns)
625 {
626 	umode_t fmode;
627 	__be32 *p;
628 
629 	p = xdr_inline_decode(xdr, NFS3_fattr_sz << 2);
630 	if (unlikely(!p))
631 		return -EIO;
632 
633 	p = xdr_decode_ftype3(p, &fmode);
634 
635 	fattr->mode = (be32_to_cpup(p++) & ~S_IFMT) | fmode;
636 	fattr->nlink = be32_to_cpup(p++);
637 	fattr->uid = make_kuid(userns, be32_to_cpup(p++));
638 	if (!uid_valid(fattr->uid))
639 		goto out_uid;
640 	fattr->gid = make_kgid(userns, be32_to_cpup(p++));
641 	if (!gid_valid(fattr->gid))
642 		goto out_gid;
643 
644 	p = xdr_decode_size3(p, &fattr->size);
645 	p = xdr_decode_size3(p, &fattr->du.nfs3.used);
646 	p = xdr_decode_specdata3(p, &fattr->rdev);
647 
648 	p = xdr_decode_hyper(p, &fattr->fsid.major);
649 	fattr->fsid.minor = 0;
650 
651 	p = xdr_decode_fileid3(p, &fattr->fileid);
652 	p = xdr_decode_nfstime3(p, &fattr->atime);
653 	p = xdr_decode_nfstime3(p, &fattr->mtime);
654 	xdr_decode_nfstime3(p, &fattr->ctime);
655 	fattr->change_attr = nfs_timespec_to_change_attr(&fattr->ctime);
656 
657 	fattr->valid |= NFS_ATTR_FATTR_V3;
658 	return 0;
659 out_uid:
660 	dprintk("NFS: returned invalid uid\n");
661 	return -EINVAL;
662 out_gid:
663 	dprintk("NFS: returned invalid gid\n");
664 	return -EINVAL;
665 }
666 
667 /*
668  * post_op_attr
669  *
670  *	union post_op_attr switch (bool attributes_follow) {
671  *	case TRUE:
672  *		fattr3	attributes;
673  *	case FALSE:
674  *		void;
675  *	};
676  */
677 static int decode_post_op_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr,
678 		struct user_namespace *userns)
679 {
680 	__be32 *p;
681 
682 	p = xdr_inline_decode(xdr, 4);
683 	if (unlikely(!p))
684 		return -EIO;
685 	if (*p != xdr_zero)
686 		return decode_fattr3(xdr, fattr, userns);
687 	return 0;
688 }
689 
690 /*
691  * wcc_attr
692  *	struct wcc_attr {
693  *		size3		size;
694  *		nfstime3	mtime;
695  *		nfstime3	ctime;
696  *	};
697  */
698 static int decode_wcc_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
699 {
700 	__be32 *p;
701 
702 	p = xdr_inline_decode(xdr, NFS3_wcc_attr_sz << 2);
703 	if (unlikely(!p))
704 		return -EIO;
705 
706 	fattr->valid |= NFS_ATTR_FATTR_PRESIZE
707 		| NFS_ATTR_FATTR_PRECHANGE
708 		| NFS_ATTR_FATTR_PREMTIME
709 		| NFS_ATTR_FATTR_PRECTIME;
710 
711 	p = xdr_decode_size3(p, &fattr->pre_size);
712 	p = xdr_decode_nfstime3(p, &fattr->pre_mtime);
713 	xdr_decode_nfstime3(p, &fattr->pre_ctime);
714 	fattr->pre_change_attr = nfs_timespec_to_change_attr(&fattr->pre_ctime);
715 
716 	return 0;
717 }
718 
719 /*
720  * pre_op_attr
721  *	union pre_op_attr switch (bool attributes_follow) {
722  *	case TRUE:
723  *		wcc_attr	attributes;
724  *	case FALSE:
725  *		void;
726  *	};
727  *
728  * wcc_data
729  *
730  *	struct wcc_data {
731  *		pre_op_attr	before;
732  *		post_op_attr	after;
733  *	};
734  */
735 static int decode_pre_op_attr(struct xdr_stream *xdr, struct nfs_fattr *fattr)
736 {
737 	__be32 *p;
738 
739 	p = xdr_inline_decode(xdr, 4);
740 	if (unlikely(!p))
741 		return -EIO;
742 	if (*p != xdr_zero)
743 		return decode_wcc_attr(xdr, fattr);
744 	return 0;
745 }
746 
747 static int decode_wcc_data(struct xdr_stream *xdr, struct nfs_fattr *fattr,
748 		struct user_namespace *userns)
749 {
750 	int error;
751 
752 	error = decode_pre_op_attr(xdr, fattr);
753 	if (unlikely(error))
754 		goto out;
755 	error = decode_post_op_attr(xdr, fattr, userns);
756 out:
757 	return error;
758 }
759 
760 /*
761  * post_op_fh3
762  *
763  *	union post_op_fh3 switch (bool handle_follows) {
764  *	case TRUE:
765  *		nfs_fh3  handle;
766  *	case FALSE:
767  *		void;
768  *	};
769  */
770 static int decode_post_op_fh3(struct xdr_stream *xdr, struct nfs_fh *fh)
771 {
772 	__be32 *p = xdr_inline_decode(xdr, 4);
773 	if (unlikely(!p))
774 		return -EIO;
775 	if (*p != xdr_zero)
776 		return decode_nfs_fh3(xdr, fh);
777 	zero_nfs_fh3(fh);
778 	return 0;
779 }
780 
781 /*
782  * diropargs3
783  *
784  *	struct diropargs3 {
785  *		nfs_fh3		dir;
786  *		filename3	name;
787  *	};
788  */
789 static void encode_diropargs3(struct xdr_stream *xdr, const struct nfs_fh *fh,
790 			      const char *name, u32 length)
791 {
792 	encode_nfs_fh3(xdr, fh);
793 	encode_filename3(xdr, name, length);
794 }
795 
796 
797 /*
798  * NFSv3 XDR encode functions
799  *
800  * NFSv3 argument types are defined in section 3.3 of RFC 1813:
801  * "NFS Version 3 Protocol Specification".
802  */
803 
804 /*
805  * 3.3.1  GETATTR3args
806  *
807  *	struct GETATTR3args {
808  *		nfs_fh3  object;
809  *	};
810  */
811 static void nfs3_xdr_enc_getattr3args(struct rpc_rqst *req,
812 				      struct xdr_stream *xdr,
813 				      const void *data)
814 {
815 	const struct nfs_fh *fh = data;
816 
817 	encode_nfs_fh3(xdr, fh);
818 }
819 
820 /*
821  * 3.3.2  SETATTR3args
822  *
823  *	union sattrguard3 switch (bool check) {
824  *	case TRUE:
825  *		nfstime3  obj_ctime;
826  *	case FALSE:
827  *		void;
828  *	};
829  *
830  *	struct SETATTR3args {
831  *		nfs_fh3		object;
832  *		sattr3		new_attributes;
833  *		sattrguard3	guard;
834  *	};
835  */
836 static void encode_sattrguard3(struct xdr_stream *xdr,
837 			       const struct nfs3_sattrargs *args)
838 {
839 	__be32 *p;
840 
841 	if (args->guard) {
842 		p = xdr_reserve_space(xdr, 4 + 8);
843 		*p++ = xdr_one;
844 		xdr_encode_nfstime3(p, &args->guardtime);
845 	} else {
846 		p = xdr_reserve_space(xdr, 4);
847 		*p = xdr_zero;
848 	}
849 }
850 
851 static void nfs3_xdr_enc_setattr3args(struct rpc_rqst *req,
852 				      struct xdr_stream *xdr,
853 				      const void *data)
854 {
855 	const struct nfs3_sattrargs *args = data;
856 	encode_nfs_fh3(xdr, args->fh);
857 	encode_sattr3(xdr, args->sattr, rpc_rqst_userns(req));
858 	encode_sattrguard3(xdr, args);
859 }
860 
861 /*
862  * 3.3.3  LOOKUP3args
863  *
864  *	struct LOOKUP3args {
865  *		diropargs3  what;
866  *	};
867  */
868 static void nfs3_xdr_enc_lookup3args(struct rpc_rqst *req,
869 				     struct xdr_stream *xdr,
870 				     const void *data)
871 {
872 	const struct nfs3_diropargs *args = data;
873 
874 	encode_diropargs3(xdr, args->fh, args->name, args->len);
875 }
876 
877 /*
878  * 3.3.4  ACCESS3args
879  *
880  *	struct ACCESS3args {
881  *		nfs_fh3		object;
882  *		uint32		access;
883  *	};
884  */
885 static void encode_access3args(struct xdr_stream *xdr,
886 			       const struct nfs3_accessargs *args)
887 {
888 	encode_nfs_fh3(xdr, args->fh);
889 	encode_uint32(xdr, args->access);
890 }
891 
892 static void nfs3_xdr_enc_access3args(struct rpc_rqst *req,
893 				     struct xdr_stream *xdr,
894 				     const void *data)
895 {
896 	const struct nfs3_accessargs *args = data;
897 
898 	encode_access3args(xdr, args);
899 }
900 
901 /*
902  * 3.3.5  READLINK3args
903  *
904  *	struct READLINK3args {
905  *		nfs_fh3	symlink;
906  *	};
907  */
908 static void nfs3_xdr_enc_readlink3args(struct rpc_rqst *req,
909 				       struct xdr_stream *xdr,
910 				       const void *data)
911 {
912 	const struct nfs3_readlinkargs *args = data;
913 
914 	encode_nfs_fh3(xdr, args->fh);
915 	rpc_prepare_reply_pages(req, args->pages, args->pgbase, args->pglen,
916 				NFS3_readlinkres_sz - NFS3_pagepad_sz);
917 }
918 
919 /*
920  * 3.3.6  READ3args
921  *
922  *	struct READ3args {
923  *		nfs_fh3		file;
924  *		offset3		offset;
925  *		count3		count;
926  *	};
927  */
928 static void encode_read3args(struct xdr_stream *xdr,
929 			     const struct nfs_pgio_args *args)
930 {
931 	__be32 *p;
932 
933 	encode_nfs_fh3(xdr, args->fh);
934 
935 	p = xdr_reserve_space(xdr, 8 + 4);
936 	p = xdr_encode_hyper(p, args->offset);
937 	*p = cpu_to_be32(args->count);
938 }
939 
940 static void nfs3_xdr_enc_read3args(struct rpc_rqst *req,
941 				   struct xdr_stream *xdr,
942 				   const void *data)
943 {
944 	const struct nfs_pgio_args *args = data;
945 	unsigned int replen = args->replen ? args->replen :
946 					     NFS3_readres_sz - NFS3_pagepad_sz;
947 
948 	encode_read3args(xdr, args);
949 	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
950 				args->count, replen);
951 	req->rq_rcv_buf.flags |= XDRBUF_READ;
952 }
953 
954 /*
955  * 3.3.7  WRITE3args
956  *
957  *	enum stable_how {
958  *		UNSTABLE  = 0,
959  *		DATA_SYNC = 1,
960  *		FILE_SYNC = 2
961  *	};
962  *
963  *	struct WRITE3args {
964  *		nfs_fh3		file;
965  *		offset3		offset;
966  *		count3		count;
967  *		stable_how	stable;
968  *		opaque		data<>;
969  *	};
970  */
971 static void encode_write3args(struct xdr_stream *xdr,
972 			      const struct nfs_pgio_args *args)
973 {
974 	__be32 *p;
975 
976 	encode_nfs_fh3(xdr, args->fh);
977 
978 	p = xdr_reserve_space(xdr, 8 + 4 + 4 + 4);
979 	p = xdr_encode_hyper(p, args->offset);
980 	*p++ = cpu_to_be32(args->count);
981 	*p++ = cpu_to_be32(args->stable);
982 	*p = cpu_to_be32(args->count);
983 	xdr_write_pages(xdr, args->pages, args->pgbase, args->count);
984 }
985 
986 static void nfs3_xdr_enc_write3args(struct rpc_rqst *req,
987 				    struct xdr_stream *xdr,
988 				    const void *data)
989 {
990 	const struct nfs_pgio_args *args = data;
991 
992 	encode_write3args(xdr, args);
993 	xdr->buf->flags |= XDRBUF_WRITE;
994 }
995 
996 /*
997  * 3.3.8  CREATE3args
998  *
999  *	enum createmode3 {
1000  *		UNCHECKED = 0,
1001  *		GUARDED   = 1,
1002  *		EXCLUSIVE = 2
1003  *	};
1004  *
1005  *	union createhow3 switch (createmode3 mode) {
1006  *	case UNCHECKED:
1007  *	case GUARDED:
1008  *		sattr3       obj_attributes;
1009  *	case EXCLUSIVE:
1010  *		createverf3  verf;
1011  *	};
1012  *
1013  *	struct CREATE3args {
1014  *		diropargs3	where;
1015  *		createhow3	how;
1016  *	};
1017  */
1018 static void encode_createhow3(struct xdr_stream *xdr,
1019 			      const struct nfs3_createargs *args,
1020 			      struct user_namespace *userns)
1021 {
1022 	encode_uint32(xdr, args->createmode);
1023 	switch (args->createmode) {
1024 	case NFS3_CREATE_UNCHECKED:
1025 	case NFS3_CREATE_GUARDED:
1026 		encode_sattr3(xdr, args->sattr, userns);
1027 		break;
1028 	case NFS3_CREATE_EXCLUSIVE:
1029 		encode_createverf3(xdr, args->verifier);
1030 		break;
1031 	default:
1032 		BUG();
1033 	}
1034 }
1035 
1036 static void nfs3_xdr_enc_create3args(struct rpc_rqst *req,
1037 				     struct xdr_stream *xdr,
1038 				     const void *data)
1039 {
1040 	const struct nfs3_createargs *args = data;
1041 
1042 	encode_diropargs3(xdr, args->fh, args->name, args->len);
1043 	encode_createhow3(xdr, args, rpc_rqst_userns(req));
1044 }
1045 
1046 /*
1047  * 3.3.9  MKDIR3args
1048  *
1049  *	struct MKDIR3args {
1050  *		diropargs3	where;
1051  *		sattr3		attributes;
1052  *	};
1053  */
1054 static void nfs3_xdr_enc_mkdir3args(struct rpc_rqst *req,
1055 				    struct xdr_stream *xdr,
1056 				    const void *data)
1057 {
1058 	const struct nfs3_mkdirargs *args = data;
1059 
1060 	encode_diropargs3(xdr, args->fh, args->name, args->len);
1061 	encode_sattr3(xdr, args->sattr, rpc_rqst_userns(req));
1062 }
1063 
1064 /*
1065  * 3.3.10  SYMLINK3args
1066  *
1067  *	struct symlinkdata3 {
1068  *		sattr3		symlink_attributes;
1069  *		nfspath3	symlink_data;
1070  *	};
1071  *
1072  *	struct SYMLINK3args {
1073  *		diropargs3	where;
1074  *		symlinkdata3	symlink;
1075  *	};
1076  */
1077 static void encode_symlinkdata3(struct xdr_stream *xdr,
1078 				const void *data,
1079 				struct user_namespace *userns)
1080 {
1081 	const struct nfs3_symlinkargs *args = data;
1082 
1083 	encode_sattr3(xdr, args->sattr, userns);
1084 	encode_nfspath3(xdr, args->pages, args->pathlen);
1085 }
1086 
1087 static void nfs3_xdr_enc_symlink3args(struct rpc_rqst *req,
1088 				      struct xdr_stream *xdr,
1089 				      const void *data)
1090 {
1091 	const struct nfs3_symlinkargs *args = data;
1092 
1093 	encode_diropargs3(xdr, args->fromfh, args->fromname, args->fromlen);
1094 	encode_symlinkdata3(xdr, args, rpc_rqst_userns(req));
1095 	xdr->buf->flags |= XDRBUF_WRITE;
1096 }
1097 
1098 /*
1099  * 3.3.11  MKNOD3args
1100  *
1101  *	struct devicedata3 {
1102  *		sattr3		dev_attributes;
1103  *		specdata3	spec;
1104  *	};
1105  *
1106  *	union mknoddata3 switch (ftype3 type) {
1107  *	case NF3CHR:
1108  *	case NF3BLK:
1109  *		devicedata3	device;
1110  *	case NF3SOCK:
1111  *	case NF3FIFO:
1112  *		sattr3		pipe_attributes;
1113  *	default:
1114  *		void;
1115  *	};
1116  *
1117  *	struct MKNOD3args {
1118  *		diropargs3	where;
1119  *		mknoddata3	what;
1120  *	};
1121  */
1122 static void encode_devicedata3(struct xdr_stream *xdr,
1123 			       const struct nfs3_mknodargs *args,
1124 			       struct user_namespace *userns)
1125 {
1126 	encode_sattr3(xdr, args->sattr, userns);
1127 	encode_specdata3(xdr, args->rdev);
1128 }
1129 
1130 static void encode_mknoddata3(struct xdr_stream *xdr,
1131 			      const struct nfs3_mknodargs *args,
1132 			      struct user_namespace *userns)
1133 {
1134 	encode_ftype3(xdr, args->type);
1135 	switch (args->type) {
1136 	case NF3CHR:
1137 	case NF3BLK:
1138 		encode_devicedata3(xdr, args, userns);
1139 		break;
1140 	case NF3SOCK:
1141 	case NF3FIFO:
1142 		encode_sattr3(xdr, args->sattr, userns);
1143 		break;
1144 	case NF3REG:
1145 	case NF3DIR:
1146 		break;
1147 	default:
1148 		BUG();
1149 	}
1150 }
1151 
1152 static void nfs3_xdr_enc_mknod3args(struct rpc_rqst *req,
1153 				    struct xdr_stream *xdr,
1154 				    const void *data)
1155 {
1156 	const struct nfs3_mknodargs *args = data;
1157 
1158 	encode_diropargs3(xdr, args->fh, args->name, args->len);
1159 	encode_mknoddata3(xdr, args, rpc_rqst_userns(req));
1160 }
1161 
1162 /*
1163  * 3.3.12  REMOVE3args
1164  *
1165  *	struct REMOVE3args {
1166  *		diropargs3  object;
1167  *	};
1168  */
1169 static void nfs3_xdr_enc_remove3args(struct rpc_rqst *req,
1170 				     struct xdr_stream *xdr,
1171 				     const void *data)
1172 {
1173 	const struct nfs_removeargs *args = data;
1174 
1175 	encode_diropargs3(xdr, args->fh, args->name.name, args->name.len);
1176 }
1177 
1178 /*
1179  * 3.3.14  RENAME3args
1180  *
1181  *	struct RENAME3args {
1182  *		diropargs3	from;
1183  *		diropargs3	to;
1184  *	};
1185  */
1186 static void nfs3_xdr_enc_rename3args(struct rpc_rqst *req,
1187 				     struct xdr_stream *xdr,
1188 				     const void *data)
1189 {
1190 	const struct nfs_renameargs *args = data;
1191 	const struct qstr *old = args->old_name;
1192 	const struct qstr *new = args->new_name;
1193 
1194 	encode_diropargs3(xdr, args->old_dir, old->name, old->len);
1195 	encode_diropargs3(xdr, args->new_dir, new->name, new->len);
1196 }
1197 
1198 /*
1199  * 3.3.15  LINK3args
1200  *
1201  *	struct LINK3args {
1202  *		nfs_fh3		file;
1203  *		diropargs3	link;
1204  *	};
1205  */
1206 static void nfs3_xdr_enc_link3args(struct rpc_rqst *req,
1207 				   struct xdr_stream *xdr,
1208 				   const void *data)
1209 {
1210 	const struct nfs3_linkargs *args = data;
1211 
1212 	encode_nfs_fh3(xdr, args->fromfh);
1213 	encode_diropargs3(xdr, args->tofh, args->toname, args->tolen);
1214 }
1215 
1216 /*
1217  * 3.3.16  READDIR3args
1218  *
1219  *	struct READDIR3args {
1220  *		nfs_fh3		dir;
1221  *		cookie3		cookie;
1222  *		cookieverf3	cookieverf;
1223  *		count3		count;
1224  *	};
1225  */
1226 static void encode_readdir3args(struct xdr_stream *xdr,
1227 				const struct nfs3_readdirargs *args)
1228 {
1229 	__be32 *p;
1230 
1231 	encode_nfs_fh3(xdr, args->fh);
1232 
1233 	p = xdr_reserve_space(xdr, 8 + NFS3_COOKIEVERFSIZE + 4);
1234 	p = xdr_encode_cookie3(p, args->cookie);
1235 	p = xdr_encode_cookieverf3(p, args->verf);
1236 	*p = cpu_to_be32(args->count);
1237 }
1238 
1239 static void nfs3_xdr_enc_readdir3args(struct rpc_rqst *req,
1240 				      struct xdr_stream *xdr,
1241 				      const void *data)
1242 {
1243 	const struct nfs3_readdirargs *args = data;
1244 
1245 	encode_readdir3args(xdr, args);
1246 	rpc_prepare_reply_pages(req, args->pages, 0, args->count,
1247 				NFS3_readdirres_sz - NFS3_pagepad_sz);
1248 }
1249 
1250 /*
1251  * 3.3.17  READDIRPLUS3args
1252  *
1253  *	struct READDIRPLUS3args {
1254  *		nfs_fh3		dir;
1255  *		cookie3		cookie;
1256  *		cookieverf3	cookieverf;
1257  *		count3		dircount;
1258  *		count3		maxcount;
1259  *	};
1260  */
1261 static void encode_readdirplus3args(struct xdr_stream *xdr,
1262 				    const struct nfs3_readdirargs *args)
1263 {
1264 	__be32 *p;
1265 
1266 	encode_nfs_fh3(xdr, args->fh);
1267 
1268 	p = xdr_reserve_space(xdr, 8 + NFS3_COOKIEVERFSIZE + 4 + 4);
1269 	p = xdr_encode_cookie3(p, args->cookie);
1270 	p = xdr_encode_cookieverf3(p, args->verf);
1271 
1272 	/*
1273 	 * readdirplus: need dircount + buffer size.
1274 	 * We just make sure we make dircount big enough
1275 	 */
1276 	*p++ = cpu_to_be32(args->count >> 3);
1277 
1278 	*p = cpu_to_be32(args->count);
1279 }
1280 
1281 static void nfs3_xdr_enc_readdirplus3args(struct rpc_rqst *req,
1282 					  struct xdr_stream *xdr,
1283 					  const void *data)
1284 {
1285 	const struct nfs3_readdirargs *args = data;
1286 
1287 	encode_readdirplus3args(xdr, args);
1288 	rpc_prepare_reply_pages(req, args->pages, 0, args->count,
1289 				NFS3_readdirres_sz - NFS3_pagepad_sz);
1290 }
1291 
1292 /*
1293  * 3.3.21  COMMIT3args
1294  *
1295  *	struct COMMIT3args {
1296  *		nfs_fh3		file;
1297  *		offset3		offset;
1298  *		count3		count;
1299  *	};
1300  */
1301 static void encode_commit3args(struct xdr_stream *xdr,
1302 			       const struct nfs_commitargs *args)
1303 {
1304 	__be32 *p;
1305 
1306 	encode_nfs_fh3(xdr, args->fh);
1307 
1308 	p = xdr_reserve_space(xdr, 8 + 4);
1309 	p = xdr_encode_hyper(p, args->offset);
1310 	*p = cpu_to_be32(args->count);
1311 }
1312 
1313 static void nfs3_xdr_enc_commit3args(struct rpc_rqst *req,
1314 				     struct xdr_stream *xdr,
1315 				     const void *data)
1316 {
1317 	const struct nfs_commitargs *args = data;
1318 
1319 	encode_commit3args(xdr, args);
1320 }
1321 
1322 #ifdef CONFIG_NFS_V3_ACL
1323 
1324 static void nfs3_xdr_enc_getacl3args(struct rpc_rqst *req,
1325 				     struct xdr_stream *xdr,
1326 				     const void *data)
1327 {
1328 	const struct nfs3_getaclargs *args = data;
1329 
1330 	encode_nfs_fh3(xdr, args->fh);
1331 	encode_uint32(xdr, args->mask);
1332 	if (args->mask & (NFS_ACL | NFS_DFACL)) {
1333 		rpc_prepare_reply_pages(req, args->pages, 0,
1334 					NFSACL_MAXPAGES << PAGE_SHIFT,
1335 					ACL3_getaclres_sz - NFS3_pagepad_sz);
1336 		req->rq_rcv_buf.flags |= XDRBUF_SPARSE_PAGES;
1337 	}
1338 }
1339 
1340 static void nfs3_xdr_enc_setacl3args(struct rpc_rqst *req,
1341 				     struct xdr_stream *xdr,
1342 				     const void *data)
1343 {
1344 	const struct nfs3_setaclargs *args = data;
1345 	unsigned int base;
1346 	int error;
1347 
1348 	encode_nfs_fh3(xdr, NFS_FH(args->inode));
1349 	encode_uint32(xdr, args->mask);
1350 
1351 	base = req->rq_slen;
1352 	if (args->npages != 0)
1353 		xdr_write_pages(xdr, args->pages, 0, args->len);
1354 	else
1355 		xdr_reserve_space(xdr, args->len);
1356 
1357 	error = nfsacl_encode(xdr->buf, base, args->inode,
1358 			    (args->mask & NFS_ACL) ?
1359 			    args->acl_access : NULL, 1, 0);
1360 	/* FIXME: this is just broken */
1361 	BUG_ON(error < 0);
1362 	error = nfsacl_encode(xdr->buf, base + error, args->inode,
1363 			    (args->mask & NFS_DFACL) ?
1364 			    args->acl_default : NULL, 1,
1365 			    NFS_ACL_DEFAULT);
1366 	BUG_ON(error < 0);
1367 }
1368 
1369 #endif  /* CONFIG_NFS_V3_ACL */
1370 
1371 /*
1372  * NFSv3 XDR decode functions
1373  *
1374  * NFSv3 result types are defined in section 3.3 of RFC 1813:
1375  * "NFS Version 3 Protocol Specification".
1376  */
1377 
1378 /*
1379  * 3.3.1  GETATTR3res
1380  *
1381  *	struct GETATTR3resok {
1382  *		fattr3		obj_attributes;
1383  *	};
1384  *
1385  *	union GETATTR3res switch (nfsstat3 status) {
1386  *	case NFS3_OK:
1387  *		GETATTR3resok  resok;
1388  *	default:
1389  *		void;
1390  *	};
1391  */
1392 static int nfs3_xdr_dec_getattr3res(struct rpc_rqst *req,
1393 				    struct xdr_stream *xdr,
1394 				    void *result)
1395 {
1396 	enum nfs_stat status;
1397 	int error;
1398 
1399 	error = decode_nfsstat3(xdr, &status);
1400 	if (unlikely(error))
1401 		goto out;
1402 	if (status != NFS3_OK)
1403 		goto out_default;
1404 	error = decode_fattr3(xdr, result, rpc_rqst_userns(req));
1405 out:
1406 	return error;
1407 out_default:
1408 	return nfs3_stat_to_errno(status);
1409 }
1410 
1411 /*
1412  * 3.3.2  SETATTR3res
1413  *
1414  *	struct SETATTR3resok {
1415  *		wcc_data  obj_wcc;
1416  *	};
1417  *
1418  *	struct SETATTR3resfail {
1419  *		wcc_data  obj_wcc;
1420  *	};
1421  *
1422  *	union SETATTR3res switch (nfsstat3 status) {
1423  *	case NFS3_OK:
1424  *		SETATTR3resok   resok;
1425  *	default:
1426  *		SETATTR3resfail resfail;
1427  *	};
1428  */
1429 static int nfs3_xdr_dec_setattr3res(struct rpc_rqst *req,
1430 				    struct xdr_stream *xdr,
1431 				    void *result)
1432 {
1433 	enum nfs_stat status;
1434 	int error;
1435 
1436 	error = decode_nfsstat3(xdr, &status);
1437 	if (unlikely(error))
1438 		goto out;
1439 	error = decode_wcc_data(xdr, result, rpc_rqst_userns(req));
1440 	if (unlikely(error))
1441 		goto out;
1442 	if (status != NFS3_OK)
1443 		goto out_status;
1444 out:
1445 	return error;
1446 out_status:
1447 	return nfs3_stat_to_errno(status);
1448 }
1449 
1450 /*
1451  * 3.3.3  LOOKUP3res
1452  *
1453  *	struct LOOKUP3resok {
1454  *		nfs_fh3		object;
1455  *		post_op_attr	obj_attributes;
1456  *		post_op_attr	dir_attributes;
1457  *	};
1458  *
1459  *	struct LOOKUP3resfail {
1460  *		post_op_attr	dir_attributes;
1461  *	};
1462  *
1463  *	union LOOKUP3res switch (nfsstat3 status) {
1464  *	case NFS3_OK:
1465  *		LOOKUP3resok	resok;
1466  *	default:
1467  *		LOOKUP3resfail	resfail;
1468  *	};
1469  */
1470 static int nfs3_xdr_dec_lookup3res(struct rpc_rqst *req,
1471 				   struct xdr_stream *xdr,
1472 				   void *data)
1473 {
1474 	struct user_namespace *userns = rpc_rqst_userns(req);
1475 	struct nfs3_diropres *result = data;
1476 	enum nfs_stat status;
1477 	int error;
1478 
1479 	error = decode_nfsstat3(xdr, &status);
1480 	if (unlikely(error))
1481 		goto out;
1482 	if (status != NFS3_OK)
1483 		goto out_default;
1484 	error = decode_nfs_fh3(xdr, result->fh);
1485 	if (unlikely(error))
1486 		goto out;
1487 	error = decode_post_op_attr(xdr, result->fattr, userns);
1488 	if (unlikely(error))
1489 		goto out;
1490 	error = decode_post_op_attr(xdr, result->dir_attr, userns);
1491 out:
1492 	return error;
1493 out_default:
1494 	error = decode_post_op_attr(xdr, result->dir_attr, userns);
1495 	if (unlikely(error))
1496 		goto out;
1497 	return nfs3_stat_to_errno(status);
1498 }
1499 
1500 /*
1501  * 3.3.4  ACCESS3res
1502  *
1503  *	struct ACCESS3resok {
1504  *		post_op_attr	obj_attributes;
1505  *		uint32		access;
1506  *	};
1507  *
1508  *	struct ACCESS3resfail {
1509  *		post_op_attr	obj_attributes;
1510  *	};
1511  *
1512  *	union ACCESS3res switch (nfsstat3 status) {
1513  *	case NFS3_OK:
1514  *		ACCESS3resok	resok;
1515  *	default:
1516  *		ACCESS3resfail	resfail;
1517  *	};
1518  */
1519 static int nfs3_xdr_dec_access3res(struct rpc_rqst *req,
1520 				   struct xdr_stream *xdr,
1521 				   void *data)
1522 {
1523 	struct nfs3_accessres *result = data;
1524 	enum nfs_stat status;
1525 	int error;
1526 
1527 	error = decode_nfsstat3(xdr, &status);
1528 	if (unlikely(error))
1529 		goto out;
1530 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
1531 	if (unlikely(error))
1532 		goto out;
1533 	if (status != NFS3_OK)
1534 		goto out_default;
1535 	error = decode_uint32(xdr, &result->access);
1536 out:
1537 	return error;
1538 out_default:
1539 	return nfs3_stat_to_errno(status);
1540 }
1541 
1542 /*
1543  * 3.3.5  READLINK3res
1544  *
1545  *	struct READLINK3resok {
1546  *		post_op_attr	symlink_attributes;
1547  *		nfspath3	data;
1548  *	};
1549  *
1550  *	struct READLINK3resfail {
1551  *		post_op_attr	symlink_attributes;
1552  *	};
1553  *
1554  *	union READLINK3res switch (nfsstat3 status) {
1555  *	case NFS3_OK:
1556  *		READLINK3resok	resok;
1557  *	default:
1558  *		READLINK3resfail resfail;
1559  *	};
1560  */
1561 static int nfs3_xdr_dec_readlink3res(struct rpc_rqst *req,
1562 				     struct xdr_stream *xdr,
1563 				     void *result)
1564 {
1565 	enum nfs_stat status;
1566 	int error;
1567 
1568 	error = decode_nfsstat3(xdr, &status);
1569 	if (unlikely(error))
1570 		goto out;
1571 	error = decode_post_op_attr(xdr, result, rpc_rqst_userns(req));
1572 	if (unlikely(error))
1573 		goto out;
1574 	if (status != NFS3_OK)
1575 		goto out_default;
1576 	error = decode_nfspath3(xdr);
1577 out:
1578 	return error;
1579 out_default:
1580 	return nfs3_stat_to_errno(status);
1581 }
1582 
1583 /*
1584  * 3.3.6  READ3res
1585  *
1586  *	struct READ3resok {
1587  *		post_op_attr	file_attributes;
1588  *		count3		count;
1589  *		bool		eof;
1590  *		opaque		data<>;
1591  *	};
1592  *
1593  *	struct READ3resfail {
1594  *		post_op_attr	file_attributes;
1595  *	};
1596  *
1597  *	union READ3res switch (nfsstat3 status) {
1598  *	case NFS3_OK:
1599  *		READ3resok	resok;
1600  *	default:
1601  *		READ3resfail	resfail;
1602  *	};
1603  */
1604 static int decode_read3resok(struct xdr_stream *xdr,
1605 			     struct nfs_pgio_res *result)
1606 {
1607 	u32 eof, count, ocount, recvd;
1608 	__be32 *p;
1609 
1610 	p = xdr_inline_decode(xdr, 4 + 4 + 4);
1611 	if (unlikely(!p))
1612 		return -EIO;
1613 	count = be32_to_cpup(p++);
1614 	eof = be32_to_cpup(p++);
1615 	ocount = be32_to_cpup(p++);
1616 	if (unlikely(ocount != count))
1617 		goto out_mismatch;
1618 	recvd = xdr_read_pages(xdr, count);
1619 	if (unlikely(count > recvd))
1620 		goto out_cheating;
1621 out:
1622 	result->eof = eof;
1623 	result->count = count;
1624 	return count;
1625 out_mismatch:
1626 	dprintk("NFS: READ count doesn't match length of opaque: "
1627 		"count %u != ocount %u\n", count, ocount);
1628 	return -EIO;
1629 out_cheating:
1630 	dprintk("NFS: server cheating in read result: "
1631 		"count %u > recvd %u\n", count, recvd);
1632 	count = recvd;
1633 	eof = 0;
1634 	goto out;
1635 }
1636 
1637 static int nfs3_xdr_dec_read3res(struct rpc_rqst *req, struct xdr_stream *xdr,
1638 				 void *data)
1639 {
1640 	struct nfs_pgio_res *result = data;
1641 	unsigned int pos;
1642 	enum nfs_stat status;
1643 	int error;
1644 
1645 	pos = xdr_stream_pos(xdr);
1646 	error = decode_nfsstat3(xdr, &status);
1647 	if (unlikely(error))
1648 		goto out;
1649 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
1650 	if (unlikely(error))
1651 		goto out;
1652 	result->op_status = status;
1653 	if (status != NFS3_OK)
1654 		goto out_status;
1655 	result->replen = 3 + ((xdr_stream_pos(xdr) - pos) >> 2);
1656 	error = decode_read3resok(xdr, result);
1657 out:
1658 	return error;
1659 out_status:
1660 	return nfs3_stat_to_errno(status);
1661 }
1662 
1663 /*
1664  * 3.3.7  WRITE3res
1665  *
1666  *	enum stable_how {
1667  *		UNSTABLE  = 0,
1668  *		DATA_SYNC = 1,
1669  *		FILE_SYNC = 2
1670  *	};
1671  *
1672  *	struct WRITE3resok {
1673  *		wcc_data	file_wcc;
1674  *		count3		count;
1675  *		stable_how	committed;
1676  *		writeverf3	verf;
1677  *	};
1678  *
1679  *	struct WRITE3resfail {
1680  *		wcc_data	file_wcc;
1681  *	};
1682  *
1683  *	union WRITE3res switch (nfsstat3 status) {
1684  *	case NFS3_OK:
1685  *		WRITE3resok	resok;
1686  *	default:
1687  *		WRITE3resfail	resfail;
1688  *	};
1689  */
1690 static int decode_write3resok(struct xdr_stream *xdr,
1691 			      struct nfs_pgio_res *result)
1692 {
1693 	__be32 *p;
1694 
1695 	p = xdr_inline_decode(xdr, 4 + 4);
1696 	if (unlikely(!p))
1697 		return -EIO;
1698 	result->count = be32_to_cpup(p++);
1699 	result->verf->committed = be32_to_cpup(p++);
1700 	if (unlikely(result->verf->committed > NFS_FILE_SYNC))
1701 		goto out_badvalue;
1702 	if (decode_writeverf3(xdr, &result->verf->verifier))
1703 		return -EIO;
1704 	return result->count;
1705 out_badvalue:
1706 	dprintk("NFS: bad stable_how value: %u\n", result->verf->committed);
1707 	return -EIO;
1708 }
1709 
1710 static int nfs3_xdr_dec_write3res(struct rpc_rqst *req, struct xdr_stream *xdr,
1711 				  void *data)
1712 {
1713 	struct nfs_pgio_res *result = data;
1714 	enum nfs_stat status;
1715 	int error;
1716 
1717 	error = decode_nfsstat3(xdr, &status);
1718 	if (unlikely(error))
1719 		goto out;
1720 	error = decode_wcc_data(xdr, result->fattr, rpc_rqst_userns(req));
1721 	if (unlikely(error))
1722 		goto out;
1723 	result->op_status = status;
1724 	if (status != NFS3_OK)
1725 		goto out_status;
1726 	error = decode_write3resok(xdr, result);
1727 out:
1728 	return error;
1729 out_status:
1730 	return nfs3_stat_to_errno(status);
1731 }
1732 
1733 /*
1734  * 3.3.8  CREATE3res
1735  *
1736  *	struct CREATE3resok {
1737  *		post_op_fh3	obj;
1738  *		post_op_attr	obj_attributes;
1739  *		wcc_data	dir_wcc;
1740  *	};
1741  *
1742  *	struct CREATE3resfail {
1743  *		wcc_data	dir_wcc;
1744  *	};
1745  *
1746  *	union CREATE3res switch (nfsstat3 status) {
1747  *	case NFS3_OK:
1748  *		CREATE3resok	resok;
1749  *	default:
1750  *		CREATE3resfail	resfail;
1751  *	};
1752  */
1753 static int decode_create3resok(struct xdr_stream *xdr,
1754 			       struct nfs3_diropres *result,
1755 			       struct user_namespace *userns)
1756 {
1757 	int error;
1758 
1759 	error = decode_post_op_fh3(xdr, result->fh);
1760 	if (unlikely(error))
1761 		goto out;
1762 	error = decode_post_op_attr(xdr, result->fattr, userns);
1763 	if (unlikely(error))
1764 		goto out;
1765 	/* The server isn't required to return a file handle.
1766 	 * If it didn't, force the client to perform a LOOKUP
1767 	 * to determine the correct file handle and attribute
1768 	 * values for the new object. */
1769 	if (result->fh->size == 0)
1770 		result->fattr->valid = 0;
1771 	error = decode_wcc_data(xdr, result->dir_attr, userns);
1772 out:
1773 	return error;
1774 }
1775 
1776 static int nfs3_xdr_dec_create3res(struct rpc_rqst *req,
1777 				   struct xdr_stream *xdr,
1778 				   void *data)
1779 {
1780 	struct user_namespace *userns = rpc_rqst_userns(req);
1781 	struct nfs3_diropres *result = data;
1782 	enum nfs_stat status;
1783 	int error;
1784 
1785 	error = decode_nfsstat3(xdr, &status);
1786 	if (unlikely(error))
1787 		goto out;
1788 	if (status != NFS3_OK)
1789 		goto out_default;
1790 	error = decode_create3resok(xdr, result, userns);
1791 out:
1792 	return error;
1793 out_default:
1794 	error = decode_wcc_data(xdr, result->dir_attr, userns);
1795 	if (unlikely(error))
1796 		goto out;
1797 	return nfs3_stat_to_errno(status);
1798 }
1799 
1800 /*
1801  * 3.3.12  REMOVE3res
1802  *
1803  *	struct REMOVE3resok {
1804  *		wcc_data    dir_wcc;
1805  *	};
1806  *
1807  *	struct REMOVE3resfail {
1808  *		wcc_data    dir_wcc;
1809  *	};
1810  *
1811  *	union REMOVE3res switch (nfsstat3 status) {
1812  *	case NFS3_OK:
1813  *		REMOVE3resok   resok;
1814  *	default:
1815  *		REMOVE3resfail resfail;
1816  *	};
1817  */
1818 static int nfs3_xdr_dec_remove3res(struct rpc_rqst *req,
1819 				   struct xdr_stream *xdr,
1820 				   void *data)
1821 {
1822 	struct nfs_removeres *result = data;
1823 	enum nfs_stat status;
1824 	int error;
1825 
1826 	error = decode_nfsstat3(xdr, &status);
1827 	if (unlikely(error))
1828 		goto out;
1829 	error = decode_wcc_data(xdr, result->dir_attr, rpc_rqst_userns(req));
1830 	if (unlikely(error))
1831 		goto out;
1832 	if (status != NFS3_OK)
1833 		goto out_status;
1834 out:
1835 	return error;
1836 out_status:
1837 	return nfs3_stat_to_errno(status);
1838 }
1839 
1840 /*
1841  * 3.3.14  RENAME3res
1842  *
1843  *	struct RENAME3resok {
1844  *		wcc_data	fromdir_wcc;
1845  *		wcc_data	todir_wcc;
1846  *	};
1847  *
1848  *	struct RENAME3resfail {
1849  *		wcc_data	fromdir_wcc;
1850  *		wcc_data	todir_wcc;
1851  *	};
1852  *
1853  *	union RENAME3res switch (nfsstat3 status) {
1854  *	case NFS3_OK:
1855  *		RENAME3resok   resok;
1856  *	default:
1857  *		RENAME3resfail resfail;
1858  *	};
1859  */
1860 static int nfs3_xdr_dec_rename3res(struct rpc_rqst *req,
1861 				   struct xdr_stream *xdr,
1862 				   void *data)
1863 {
1864 	struct user_namespace *userns = rpc_rqst_userns(req);
1865 	struct nfs_renameres *result = data;
1866 	enum nfs_stat status;
1867 	int error;
1868 
1869 	error = decode_nfsstat3(xdr, &status);
1870 	if (unlikely(error))
1871 		goto out;
1872 	error = decode_wcc_data(xdr, result->old_fattr, userns);
1873 	if (unlikely(error))
1874 		goto out;
1875 	error = decode_wcc_data(xdr, result->new_fattr, userns);
1876 	if (unlikely(error))
1877 		goto out;
1878 	if (status != NFS3_OK)
1879 		goto out_status;
1880 out:
1881 	return error;
1882 out_status:
1883 	return nfs3_stat_to_errno(status);
1884 }
1885 
1886 /*
1887  * 3.3.15  LINK3res
1888  *
1889  *	struct LINK3resok {
1890  *		post_op_attr	file_attributes;
1891  *		wcc_data	linkdir_wcc;
1892  *	};
1893  *
1894  *	struct LINK3resfail {
1895  *		post_op_attr	file_attributes;
1896  *		wcc_data	linkdir_wcc;
1897  *	};
1898  *
1899  *	union LINK3res switch (nfsstat3 status) {
1900  *	case NFS3_OK:
1901  *		LINK3resok	resok;
1902  *	default:
1903  *		LINK3resfail	resfail;
1904  *	};
1905  */
1906 static int nfs3_xdr_dec_link3res(struct rpc_rqst *req, struct xdr_stream *xdr,
1907 				 void *data)
1908 {
1909 	struct user_namespace *userns = rpc_rqst_userns(req);
1910 	struct nfs3_linkres *result = data;
1911 	enum nfs_stat status;
1912 	int error;
1913 
1914 	error = decode_nfsstat3(xdr, &status);
1915 	if (unlikely(error))
1916 		goto out;
1917 	error = decode_post_op_attr(xdr, result->fattr, userns);
1918 	if (unlikely(error))
1919 		goto out;
1920 	error = decode_wcc_data(xdr, result->dir_attr, userns);
1921 	if (unlikely(error))
1922 		goto out;
1923 	if (status != NFS3_OK)
1924 		goto out_status;
1925 out:
1926 	return error;
1927 out_status:
1928 	return nfs3_stat_to_errno(status);
1929 }
1930 
1931 /**
1932  * nfs3_decode_dirent - Decode a single NFSv3 directory entry stored in
1933  *			the local page cache
1934  * @xdr: XDR stream where entry resides
1935  * @entry: buffer to fill in with entry data
1936  * @plus: boolean indicating whether this should be a readdirplus entry
1937  *
1938  * Returns zero if successful, otherwise a negative errno value is
1939  * returned.
1940  *
1941  * This function is not invoked during READDIR reply decoding, but
1942  * rather whenever an application invokes the getdents(2) system call
1943  * on a directory already in our cache.
1944  *
1945  * 3.3.16  entry3
1946  *
1947  *	struct entry3 {
1948  *		fileid3		fileid;
1949  *		filename3	name;
1950  *		cookie3		cookie;
1951  *		fhandle3	filehandle;
1952  *		post_op_attr3	attributes;
1953  *		entry3		*nextentry;
1954  *	};
1955  *
1956  * 3.3.17  entryplus3
1957  *	struct entryplus3 {
1958  *		fileid3		fileid;
1959  *		filename3	name;
1960  *		cookie3		cookie;
1961  *		post_op_attr	name_attributes;
1962  *		post_op_fh3	name_handle;
1963  *		entryplus3	*nextentry;
1964  *	};
1965  */
1966 int nfs3_decode_dirent(struct xdr_stream *xdr, struct nfs_entry *entry,
1967 		       bool plus)
1968 {
1969 	struct user_namespace *userns = rpc_userns(entry->server->client);
1970 	struct nfs_entry old = *entry;
1971 	__be32 *p;
1972 	int error;
1973 	u64 new_cookie;
1974 
1975 	p = xdr_inline_decode(xdr, 4);
1976 	if (unlikely(!p))
1977 		return -EAGAIN;
1978 	if (*p == xdr_zero) {
1979 		p = xdr_inline_decode(xdr, 4);
1980 		if (unlikely(!p))
1981 			return -EAGAIN;
1982 		if (*p == xdr_zero)
1983 			return -EAGAIN;
1984 		entry->eof = 1;
1985 		return -EBADCOOKIE;
1986 	}
1987 
1988 	error = decode_fileid3(xdr, &entry->ino);
1989 	if (unlikely(error))
1990 		return error;
1991 
1992 	error = decode_inline_filename3(xdr, &entry->name, &entry->len);
1993 	if (unlikely(error))
1994 		return error;
1995 
1996 	error = decode_cookie3(xdr, &new_cookie);
1997 	if (unlikely(error))
1998 		return error;
1999 
2000 	entry->d_type = DT_UNKNOWN;
2001 
2002 	if (plus) {
2003 		entry->fattr->valid = 0;
2004 		error = decode_post_op_attr(xdr, entry->fattr, userns);
2005 		if (unlikely(error))
2006 			return error;
2007 		if (entry->fattr->valid & NFS_ATTR_FATTR_V3)
2008 			entry->d_type = nfs_umode_to_dtype(entry->fattr->mode);
2009 
2010 		if (entry->fattr->fileid != entry->ino) {
2011 			entry->fattr->mounted_on_fileid = entry->ino;
2012 			entry->fattr->valid |= NFS_ATTR_FATTR_MOUNTED_ON_FILEID;
2013 		}
2014 
2015 		/* In fact, a post_op_fh3: */
2016 		p = xdr_inline_decode(xdr, 4);
2017 		if (unlikely(!p))
2018 			return -EAGAIN;
2019 		if (*p != xdr_zero) {
2020 			error = decode_nfs_fh3(xdr, entry->fh);
2021 			if (unlikely(error)) {
2022 				if (error == -E2BIG)
2023 					goto out_truncated;
2024 				return error;
2025 			}
2026 		} else
2027 			zero_nfs_fh3(entry->fh);
2028 	}
2029 
2030 	entry->prev_cookie = entry->cookie;
2031 	entry->cookie = new_cookie;
2032 
2033 	return 0;
2034 
2035 out_truncated:
2036 	dprintk("NFS: directory entry contains invalid file handle\n");
2037 	*entry = old;
2038 	return -EAGAIN;
2039 }
2040 
2041 /*
2042  * 3.3.16  READDIR3res
2043  *
2044  *	struct dirlist3 {
2045  *		entry3		*entries;
2046  *		bool		eof;
2047  *	};
2048  *
2049  *	struct READDIR3resok {
2050  *		post_op_attr	dir_attributes;
2051  *		cookieverf3	cookieverf;
2052  *		dirlist3	reply;
2053  *	};
2054  *
2055  *	struct READDIR3resfail {
2056  *		post_op_attr	dir_attributes;
2057  *	};
2058  *
2059  *	union READDIR3res switch (nfsstat3 status) {
2060  *	case NFS3_OK:
2061  *		READDIR3resok	resok;
2062  *	default:
2063  *		READDIR3resfail	resfail;
2064  *	};
2065  *
2066  * Read the directory contents into the page cache, but otherwise
2067  * don't touch them.  The actual decoding is done by nfs3_decode_entry()
2068  * during subsequent nfs_readdir() calls.
2069  */
2070 static int decode_dirlist3(struct xdr_stream *xdr)
2071 {
2072 	return xdr_read_pages(xdr, xdr->buf->page_len);
2073 }
2074 
2075 static int decode_readdir3resok(struct xdr_stream *xdr,
2076 				struct nfs3_readdirres *result,
2077 				struct user_namespace *userns)
2078 {
2079 	int error;
2080 
2081 	error = decode_post_op_attr(xdr, result->dir_attr, userns);
2082 	if (unlikely(error))
2083 		goto out;
2084 	/* XXX: do we need to check if result->verf != NULL ? */
2085 	error = decode_cookieverf3(xdr, result->verf);
2086 	if (unlikely(error))
2087 		goto out;
2088 	error = decode_dirlist3(xdr);
2089 out:
2090 	return error;
2091 }
2092 
2093 static int nfs3_xdr_dec_readdir3res(struct rpc_rqst *req,
2094 				    struct xdr_stream *xdr,
2095 				    void *data)
2096 {
2097 	struct nfs3_readdirres *result = data;
2098 	enum nfs_stat status;
2099 	int error;
2100 
2101 	error = decode_nfsstat3(xdr, &status);
2102 	if (unlikely(error))
2103 		goto out;
2104 	if (status != NFS3_OK)
2105 		goto out_default;
2106 	error = decode_readdir3resok(xdr, result, rpc_rqst_userns(req));
2107 out:
2108 	return error;
2109 out_default:
2110 	error = decode_post_op_attr(xdr, result->dir_attr, rpc_rqst_userns(req));
2111 	if (unlikely(error))
2112 		goto out;
2113 	return nfs3_stat_to_errno(status);
2114 }
2115 
2116 /*
2117  * 3.3.18  FSSTAT3res
2118  *
2119  *	struct FSSTAT3resok {
2120  *		post_op_attr	obj_attributes;
2121  *		size3		tbytes;
2122  *		size3		fbytes;
2123  *		size3		abytes;
2124  *		size3		tfiles;
2125  *		size3		ffiles;
2126  *		size3		afiles;
2127  *		uint32		invarsec;
2128  *	};
2129  *
2130  *	struct FSSTAT3resfail {
2131  *		post_op_attr	obj_attributes;
2132  *	};
2133  *
2134  *	union FSSTAT3res switch (nfsstat3 status) {
2135  *	case NFS3_OK:
2136  *		FSSTAT3resok	resok;
2137  *	default:
2138  *		FSSTAT3resfail	resfail;
2139  *	};
2140  */
2141 static int decode_fsstat3resok(struct xdr_stream *xdr,
2142 			       struct nfs_fsstat *result)
2143 {
2144 	__be32 *p;
2145 
2146 	p = xdr_inline_decode(xdr, 8 * 6 + 4);
2147 	if (unlikely(!p))
2148 		return -EIO;
2149 	p = xdr_decode_size3(p, &result->tbytes);
2150 	p = xdr_decode_size3(p, &result->fbytes);
2151 	p = xdr_decode_size3(p, &result->abytes);
2152 	p = xdr_decode_size3(p, &result->tfiles);
2153 	p = xdr_decode_size3(p, &result->ffiles);
2154 	xdr_decode_size3(p, &result->afiles);
2155 	/* ignore invarsec */
2156 	return 0;
2157 }
2158 
2159 static int nfs3_xdr_dec_fsstat3res(struct rpc_rqst *req,
2160 				   struct xdr_stream *xdr,
2161 				   void *data)
2162 {
2163 	struct nfs_fsstat *result = data;
2164 	enum nfs_stat status;
2165 	int error;
2166 
2167 	error = decode_nfsstat3(xdr, &status);
2168 	if (unlikely(error))
2169 		goto out;
2170 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
2171 	if (unlikely(error))
2172 		goto out;
2173 	if (status != NFS3_OK)
2174 		goto out_status;
2175 	error = decode_fsstat3resok(xdr, result);
2176 out:
2177 	return error;
2178 out_status:
2179 	return nfs3_stat_to_errno(status);
2180 }
2181 
2182 /*
2183  * 3.3.19  FSINFO3res
2184  *
2185  *	struct FSINFO3resok {
2186  *		post_op_attr	obj_attributes;
2187  *		uint32		rtmax;
2188  *		uint32		rtpref;
2189  *		uint32		rtmult;
2190  *		uint32		wtmax;
2191  *		uint32		wtpref;
2192  *		uint32		wtmult;
2193  *		uint32		dtpref;
2194  *		size3		maxfilesize;
2195  *		nfstime3	time_delta;
2196  *		uint32		properties;
2197  *	};
2198  *
2199  *	struct FSINFO3resfail {
2200  *		post_op_attr	obj_attributes;
2201  *	};
2202  *
2203  *	union FSINFO3res switch (nfsstat3 status) {
2204  *	case NFS3_OK:
2205  *		FSINFO3resok	resok;
2206  *	default:
2207  *		FSINFO3resfail	resfail;
2208  *	};
2209  */
2210 static int decode_fsinfo3resok(struct xdr_stream *xdr,
2211 			       struct nfs_fsinfo *result)
2212 {
2213 	__be32 *p;
2214 
2215 	p = xdr_inline_decode(xdr, 4 * 7 + 8 + 8 + 4);
2216 	if (unlikely(!p))
2217 		return -EIO;
2218 	result->rtmax  = be32_to_cpup(p++);
2219 	result->rtpref = be32_to_cpup(p++);
2220 	result->rtmult = be32_to_cpup(p++);
2221 	result->wtmax  = be32_to_cpup(p++);
2222 	result->wtpref = be32_to_cpup(p++);
2223 	result->wtmult = be32_to_cpup(p++);
2224 	result->dtpref = be32_to_cpup(p++);
2225 	p = xdr_decode_size3(p, &result->maxfilesize);
2226 	xdr_decode_nfstime3(p, &result->time_delta);
2227 
2228 	/* ignore properties */
2229 	result->lease_time = 0;
2230 	result->change_attr_type = NFS4_CHANGE_TYPE_IS_UNDEFINED;
2231 	return 0;
2232 }
2233 
2234 static int nfs3_xdr_dec_fsinfo3res(struct rpc_rqst *req,
2235 				   struct xdr_stream *xdr,
2236 				   void *data)
2237 {
2238 	struct nfs_fsinfo *result = data;
2239 	enum nfs_stat status;
2240 	int error;
2241 
2242 	error = decode_nfsstat3(xdr, &status);
2243 	if (unlikely(error))
2244 		goto out;
2245 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
2246 	if (unlikely(error))
2247 		goto out;
2248 	if (status != NFS3_OK)
2249 		goto out_status;
2250 	error = decode_fsinfo3resok(xdr, result);
2251 out:
2252 	return error;
2253 out_status:
2254 	return nfs3_stat_to_errno(status);
2255 }
2256 
2257 /*
2258  * 3.3.20  PATHCONF3res
2259  *
2260  *	struct PATHCONF3resok {
2261  *		post_op_attr	obj_attributes;
2262  *		uint32		linkmax;
2263  *		uint32		name_max;
2264  *		bool		no_trunc;
2265  *		bool		chown_restricted;
2266  *		bool		case_insensitive;
2267  *		bool		case_preserving;
2268  *	};
2269  *
2270  *	struct PATHCONF3resfail {
2271  *		post_op_attr	obj_attributes;
2272  *	};
2273  *
2274  *	union PATHCONF3res switch (nfsstat3 status) {
2275  *	case NFS3_OK:
2276  *		PATHCONF3resok	resok;
2277  *	default:
2278  *		PATHCONF3resfail resfail;
2279  *	};
2280  */
2281 static int decode_pathconf3resok(struct xdr_stream *xdr,
2282 				 struct nfs_pathconf *result)
2283 {
2284 	__be32 *p;
2285 
2286 	p = xdr_inline_decode(xdr, 4 * 6);
2287 	if (unlikely(!p))
2288 		return -EIO;
2289 	result->max_link = be32_to_cpup(p++);
2290 	result->max_namelen = be32_to_cpup(p);
2291 	/* ignore remaining fields */
2292 	return 0;
2293 }
2294 
2295 static int nfs3_xdr_dec_pathconf3res(struct rpc_rqst *req,
2296 				     struct xdr_stream *xdr,
2297 				     void *data)
2298 {
2299 	struct nfs_pathconf *result = data;
2300 	enum nfs_stat status;
2301 	int error;
2302 
2303 	error = decode_nfsstat3(xdr, &status);
2304 	if (unlikely(error))
2305 		goto out;
2306 	error = decode_post_op_attr(xdr, result->fattr, rpc_rqst_userns(req));
2307 	if (unlikely(error))
2308 		goto out;
2309 	if (status != NFS3_OK)
2310 		goto out_status;
2311 	error = decode_pathconf3resok(xdr, result);
2312 out:
2313 	return error;
2314 out_status:
2315 	return nfs3_stat_to_errno(status);
2316 }
2317 
2318 /*
2319  * 3.3.21  COMMIT3res
2320  *
2321  *	struct COMMIT3resok {
2322  *		wcc_data	file_wcc;
2323  *		writeverf3	verf;
2324  *	};
2325  *
2326  *	struct COMMIT3resfail {
2327  *		wcc_data	file_wcc;
2328  *	};
2329  *
2330  *	union COMMIT3res switch (nfsstat3 status) {
2331  *	case NFS3_OK:
2332  *		COMMIT3resok	resok;
2333  *	default:
2334  *		COMMIT3resfail	resfail;
2335  *	};
2336  */
2337 static int nfs3_xdr_dec_commit3res(struct rpc_rqst *req,
2338 				   struct xdr_stream *xdr,
2339 				   void *data)
2340 {
2341 	struct nfs_commitres *result = data;
2342 	struct nfs_writeverf *verf = result->verf;
2343 	enum nfs_stat status;
2344 	int error;
2345 
2346 	error = decode_nfsstat3(xdr, &status);
2347 	if (unlikely(error))
2348 		goto out;
2349 	error = decode_wcc_data(xdr, result->fattr, rpc_rqst_userns(req));
2350 	if (unlikely(error))
2351 		goto out;
2352 	result->op_status = status;
2353 	if (status != NFS3_OK)
2354 		goto out_status;
2355 	error = decode_writeverf3(xdr, &verf->verifier);
2356 	if (!error)
2357 		verf->committed = NFS_FILE_SYNC;
2358 out:
2359 	return error;
2360 out_status:
2361 	return nfs3_stat_to_errno(status);
2362 }
2363 
2364 #ifdef CONFIG_NFS_V3_ACL
2365 
2366 static inline int decode_getacl3resok(struct xdr_stream *xdr,
2367 				      struct nfs3_getaclres *result,
2368 				      struct user_namespace *userns)
2369 {
2370 	struct posix_acl **acl;
2371 	unsigned int *aclcnt;
2372 	size_t hdrlen;
2373 	int error;
2374 
2375 	error = decode_post_op_attr(xdr, result->fattr, userns);
2376 	if (unlikely(error))
2377 		goto out;
2378 	error = decode_uint32(xdr, &result->mask);
2379 	if (unlikely(error))
2380 		goto out;
2381 	error = -EINVAL;
2382 	if (result->mask & ~(NFS_ACL|NFS_ACLCNT|NFS_DFACL|NFS_DFACLCNT))
2383 		goto out;
2384 
2385 	hdrlen = xdr_stream_pos(xdr);
2386 
2387 	acl = NULL;
2388 	if (result->mask & NFS_ACL)
2389 		acl = &result->acl_access;
2390 	aclcnt = NULL;
2391 	if (result->mask & NFS_ACLCNT)
2392 		aclcnt = &result->acl_access_count;
2393 	error = nfsacl_decode(xdr->buf, hdrlen, aclcnt, acl);
2394 	if (unlikely(error <= 0))
2395 		goto out;
2396 
2397 	acl = NULL;
2398 	if (result->mask & NFS_DFACL)
2399 		acl = &result->acl_default;
2400 	aclcnt = NULL;
2401 	if (result->mask & NFS_DFACLCNT)
2402 		aclcnt = &result->acl_default_count;
2403 	error = nfsacl_decode(xdr->buf, hdrlen + error, aclcnt, acl);
2404 	if (unlikely(error <= 0))
2405 		return error;
2406 	error = 0;
2407 out:
2408 	return error;
2409 }
2410 
2411 static int nfs3_xdr_dec_getacl3res(struct rpc_rqst *req,
2412 				   struct xdr_stream *xdr,
2413 				   void *result)
2414 {
2415 	enum nfs_stat status;
2416 	int error;
2417 
2418 	error = decode_nfsstat3(xdr, &status);
2419 	if (unlikely(error))
2420 		goto out;
2421 	if (status != NFS3_OK)
2422 		goto out_default;
2423 	error = decode_getacl3resok(xdr, result, rpc_rqst_userns(req));
2424 out:
2425 	return error;
2426 out_default:
2427 	return nfs3_stat_to_errno(status);
2428 }
2429 
2430 static int nfs3_xdr_dec_setacl3res(struct rpc_rqst *req,
2431 				   struct xdr_stream *xdr,
2432 				   void *result)
2433 {
2434 	enum nfs_stat status;
2435 	int error;
2436 
2437 	error = decode_nfsstat3(xdr, &status);
2438 	if (unlikely(error))
2439 		goto out;
2440 	if (status != NFS3_OK)
2441 		goto out_default;
2442 	error = decode_post_op_attr(xdr, result, rpc_rqst_userns(req));
2443 out:
2444 	return error;
2445 out_default:
2446 	return nfs3_stat_to_errno(status);
2447 }
2448 
2449 #endif  /* CONFIG_NFS_V3_ACL */
2450 
2451 
2452 /*
2453  * We need to translate between nfs status return values and
2454  * the local errno values which may not be the same.
2455  */
2456 static const struct {
2457 	int stat;
2458 	int errno;
2459 } nfs_errtbl[] = {
2460 	{ NFS_OK,		0		},
2461 	{ NFSERR_PERM,		-EPERM		},
2462 	{ NFSERR_NOENT,		-ENOENT		},
2463 	{ NFSERR_IO,		-errno_NFSERR_IO},
2464 	{ NFSERR_NXIO,		-ENXIO		},
2465 /*	{ NFSERR_EAGAIN,	-EAGAIN		}, */
2466 	{ NFSERR_ACCES,		-EACCES		},
2467 	{ NFSERR_EXIST,		-EEXIST		},
2468 	{ NFSERR_XDEV,		-EXDEV		},
2469 	{ NFSERR_NODEV,		-ENODEV		},
2470 	{ NFSERR_NOTDIR,	-ENOTDIR	},
2471 	{ NFSERR_ISDIR,		-EISDIR		},
2472 	{ NFSERR_INVAL,		-EINVAL		},
2473 	{ NFSERR_FBIG,		-EFBIG		},
2474 	{ NFSERR_NOSPC,		-ENOSPC		},
2475 	{ NFSERR_ROFS,		-EROFS		},
2476 	{ NFSERR_MLINK,		-EMLINK		},
2477 	{ NFSERR_NAMETOOLONG,	-ENAMETOOLONG	},
2478 	{ NFSERR_NOTEMPTY,	-ENOTEMPTY	},
2479 	{ NFSERR_DQUOT,		-EDQUOT		},
2480 	{ NFSERR_STALE,		-ESTALE		},
2481 	{ NFSERR_REMOTE,	-EREMOTE	},
2482 #ifdef EWFLUSH
2483 	{ NFSERR_WFLUSH,	-EWFLUSH	},
2484 #endif
2485 	{ NFSERR_BADHANDLE,	-EBADHANDLE	},
2486 	{ NFSERR_NOT_SYNC,	-ENOTSYNC	},
2487 	{ NFSERR_BAD_COOKIE,	-EBADCOOKIE	},
2488 	{ NFSERR_NOTSUPP,	-ENOTSUPP	},
2489 	{ NFSERR_TOOSMALL,	-ETOOSMALL	},
2490 	{ NFSERR_SERVERFAULT,	-EREMOTEIO	},
2491 	{ NFSERR_BADTYPE,	-EBADTYPE	},
2492 	{ NFSERR_JUKEBOX,	-EJUKEBOX	},
2493 	{ -1,			-EIO		}
2494 };
2495 
2496 /**
2497  * nfs3_stat_to_errno - convert an NFS status code to a local errno
2498  * @status: NFS status code to convert
2499  *
2500  * Returns a local errno value, or -EIO if the NFS status code is
2501  * not recognized.  This function is used jointly by NFSv2 and NFSv3.
2502  */
2503 static int nfs3_stat_to_errno(enum nfs_stat status)
2504 {
2505 	int i;
2506 
2507 	for (i = 0; nfs_errtbl[i].stat != -1; i++) {
2508 		if (nfs_errtbl[i].stat == (int)status)
2509 			return nfs_errtbl[i].errno;
2510 	}
2511 	dprintk("NFS: Unrecognized nfs status value: %u\n", status);
2512 	return nfs_errtbl[i].errno;
2513 }
2514 
2515 
2516 #define PROC(proc, argtype, restype, timer)				\
2517 [NFS3PROC_##proc] = {							\
2518 	.p_proc      = NFS3PROC_##proc,					\
2519 	.p_encode    = nfs3_xdr_enc_##argtype##3args,			\
2520 	.p_decode    = nfs3_xdr_dec_##restype##3res,			\
2521 	.p_arglen    = NFS3_##argtype##args_sz,				\
2522 	.p_replen    = NFS3_##restype##res_sz,				\
2523 	.p_timer     = timer,						\
2524 	.p_statidx   = NFS3PROC_##proc,					\
2525 	.p_name      = #proc,						\
2526 	}
2527 
2528 const struct rpc_procinfo nfs3_procedures[] = {
2529 	PROC(GETATTR,		getattr,	getattr,	1),
2530 	PROC(SETATTR,		setattr,	setattr,	0),
2531 	PROC(LOOKUP,		lookup,		lookup,		2),
2532 	PROC(ACCESS,		access,		access,		1),
2533 	PROC(READLINK,		readlink,	readlink,	3),
2534 	PROC(READ,		read,		read,		3),
2535 	PROC(WRITE,		write,		write,		4),
2536 	PROC(CREATE,		create,		create,		0),
2537 	PROC(MKDIR,		mkdir,		create,		0),
2538 	PROC(SYMLINK,		symlink,	create,		0),
2539 	PROC(MKNOD,		mknod,		create,		0),
2540 	PROC(REMOVE,		remove,		remove,		0),
2541 	PROC(RMDIR,		lookup,		setattr,	0),
2542 	PROC(RENAME,		rename,		rename,		0),
2543 	PROC(LINK,		link,		link,		0),
2544 	PROC(READDIR,		readdir,	readdir,	3),
2545 	PROC(READDIRPLUS,	readdirplus,	readdir,	3),
2546 	PROC(FSSTAT,		getattr,	fsstat,		0),
2547 	PROC(FSINFO,		getattr,	fsinfo,		0),
2548 	PROC(PATHCONF,		getattr,	pathconf,	0),
2549 	PROC(COMMIT,		commit,		commit,		5),
2550 };
2551 
2552 static unsigned int nfs_version3_counts[ARRAY_SIZE(nfs3_procedures)];
2553 const struct rpc_version nfs_version3 = {
2554 	.number			= 3,
2555 	.nrprocs		= ARRAY_SIZE(nfs3_procedures),
2556 	.procs			= nfs3_procedures,
2557 	.counts			= nfs_version3_counts,
2558 };
2559 
2560 #ifdef CONFIG_NFS_V3_ACL
2561 static const struct rpc_procinfo nfs3_acl_procedures[] = {
2562 	[ACLPROC3_GETACL] = {
2563 		.p_proc = ACLPROC3_GETACL,
2564 		.p_encode = nfs3_xdr_enc_getacl3args,
2565 		.p_decode = nfs3_xdr_dec_getacl3res,
2566 		.p_arglen = ACL3_getaclargs_sz,
2567 		.p_replen = ACL3_getaclres_sz,
2568 		.p_timer = 1,
2569 		.p_name = "GETACL",
2570 	},
2571 	[ACLPROC3_SETACL] = {
2572 		.p_proc = ACLPROC3_SETACL,
2573 		.p_encode = nfs3_xdr_enc_setacl3args,
2574 		.p_decode = nfs3_xdr_dec_setacl3res,
2575 		.p_arglen = ACL3_setaclargs_sz,
2576 		.p_replen = ACL3_setaclres_sz,
2577 		.p_timer = 0,
2578 		.p_name = "SETACL",
2579 	},
2580 };
2581 
2582 static unsigned int nfs3_acl_counts[ARRAY_SIZE(nfs3_acl_procedures)];
2583 const struct rpc_version nfsacl_version3 = {
2584 	.number			= 3,
2585 	.nrprocs		= ARRAY_SIZE(nfs3_acl_procedures),
2586 	.procs			= nfs3_acl_procedures,
2587 	.counts			= nfs3_acl_counts,
2588 };
2589 #endif  /* CONFIG_NFS_V3_ACL */
2590