xref: /openbmc/linux/fs/nfs/nfs42xdr.c (revision 64edd55d0f1908220f6a4a53ff40c2b42b1bbfd5)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  * Copyright (c) 2014 Anna Schumaker <Anna.Schumaker@Netapp.com>
4  */
5 #ifndef __LINUX_FS_NFS_NFS4_2XDR_H
6 #define __LINUX_FS_NFS_NFS4_2XDR_H
7 
8 #include "nfs42.h"
9 
10 /* Not limited by NFS itself, limited by the generic xattr code */
11 #define nfs4_xattr_name_maxsz   XDR_QUADLEN(XATTR_NAME_MAX)
12 
13 #define encode_fallocate_maxsz		(encode_stateid_maxsz + \
14 					 2 /* offset */ + \
15 					 2 /* length */)
16 #define NFS42_WRITE_RES_SIZE		(1 /* wr_callback_id size */ +\
17 					 XDR_QUADLEN(NFS4_STATEID_SIZE) + \
18 					 2 /* wr_count */ + \
19 					 1 /* wr_committed */ + \
20 					 XDR_QUADLEN(NFS4_VERIFIER_SIZE))
21 #define encode_allocate_maxsz		(op_encode_hdr_maxsz + \
22 					 encode_fallocate_maxsz)
23 #define decode_allocate_maxsz		(op_decode_hdr_maxsz)
24 #define encode_copy_maxsz		(op_encode_hdr_maxsz +          \
25 					 XDR_QUADLEN(NFS4_STATEID_SIZE) + \
26 					 XDR_QUADLEN(NFS4_STATEID_SIZE) + \
27 					 2 + 2 + 2 + 1 + 1 + 1 +\
28 					 1 + /* One cnr_source_server */\
29 					 1 + /* nl4_type */ \
30 					 1 + XDR_QUADLEN(NFS4_OPAQUE_LIMIT))
31 #define decode_copy_maxsz		(op_decode_hdr_maxsz + \
32 					 NFS42_WRITE_RES_SIZE + \
33 					 1 /* cr_consecutive */ + \
34 					 1 /* cr_synchronous */)
35 #define encode_offload_cancel_maxsz	(op_encode_hdr_maxsz + \
36 					 XDR_QUADLEN(NFS4_STATEID_SIZE))
37 #define decode_offload_cancel_maxsz	(op_decode_hdr_maxsz)
38 #define encode_copy_notify_maxsz	(op_encode_hdr_maxsz + \
39 					 XDR_QUADLEN(NFS4_STATEID_SIZE) + \
40 					 1 + /* nl4_type */ \
41 					 1 + XDR_QUADLEN(NFS4_OPAQUE_LIMIT))
42 #define decode_copy_notify_maxsz	(op_decode_hdr_maxsz + \
43 					 3 + /* cnr_lease_time */\
44 					 XDR_QUADLEN(NFS4_STATEID_SIZE) + \
45 					 1 + /* Support 1 cnr_source_server */\
46 					 1 + /* nl4_type */ \
47 					 1 + XDR_QUADLEN(NFS4_OPAQUE_LIMIT))
48 #define encode_deallocate_maxsz		(op_encode_hdr_maxsz + \
49 					 encode_fallocate_maxsz)
50 #define decode_deallocate_maxsz		(op_decode_hdr_maxsz)
51 #define encode_read_plus_maxsz		(op_encode_hdr_maxsz + \
52 					 encode_stateid_maxsz + 3)
53 #define NFS42_READ_PLUS_DATA_SEGMENT_SIZE \
54 					(1 /* data_content4 */ + \
55 					 2 /* data_info4.di_offset */ + \
56 					 1 /* data_info4.di_length */)
57 #define decode_read_plus_maxsz		(op_decode_hdr_maxsz + \
58 					 1 /* rpr_eof */ + \
59 					 1 /* rpr_contents count */ + \
60 					 NFS42_READ_PLUS_DATA_SEGMENT_SIZE)
61 #define encode_seek_maxsz		(op_encode_hdr_maxsz + \
62 					 encode_stateid_maxsz + \
63 					 2 /* offset */ + \
64 					 1 /* whence */)
65 #define decode_seek_maxsz		(op_decode_hdr_maxsz + \
66 					 1 /* eof */ + \
67 					 1 /* whence */ + \
68 					 2 /* offset */ + \
69 					 2 /* length */)
70 #define encode_io_info_maxsz		4
71 #define encode_layoutstats_maxsz	(op_decode_hdr_maxsz + \
72 					2 /* offset */ + \
73 					2 /* length */ + \
74 					encode_stateid_maxsz + \
75 					encode_io_info_maxsz + \
76 					encode_io_info_maxsz + \
77 					1 /* opaque devaddr4 length */ + \
78 					XDR_QUADLEN(PNFS_LAYOUTSTATS_MAXSIZE))
79 #define decode_layoutstats_maxsz	(op_decode_hdr_maxsz)
80 #define encode_device_error_maxsz	(XDR_QUADLEN(NFS4_DEVICEID4_SIZE) + \
81 					1 /* status */ + 1 /* opnum */)
82 #define encode_layouterror_maxsz	(op_decode_hdr_maxsz + \
83 					2 /* offset */ + \
84 					2 /* length */ + \
85 					encode_stateid_maxsz + \
86 					1 /* Array size */ + \
87 					encode_device_error_maxsz)
88 #define decode_layouterror_maxsz	(op_decode_hdr_maxsz)
89 #define encode_clone_maxsz		(encode_stateid_maxsz + \
90 					encode_stateid_maxsz + \
91 					2 /* src offset */ + \
92 					2 /* dst offset */ + \
93 					2 /* count */)
94 #define decode_clone_maxsz		(op_decode_hdr_maxsz)
95 #define encode_getxattr_maxsz		(op_encode_hdr_maxsz + 1 + \
96 					 nfs4_xattr_name_maxsz)
97 #define decode_getxattr_maxsz		(op_decode_hdr_maxsz + 1 + pagepad_maxsz)
98 #define encode_setxattr_maxsz		(op_encode_hdr_maxsz + \
99 					 1 + nfs4_xattr_name_maxsz + 1)
100 #define decode_setxattr_maxsz		(op_decode_hdr_maxsz + decode_change_info_maxsz)
101 #define encode_listxattrs_maxsz		(op_encode_hdr_maxsz + 2 + 1)
102 #define decode_listxattrs_maxsz		(op_decode_hdr_maxsz + 2 + 1 + 1 + 1)
103 #define encode_removexattr_maxsz	(op_encode_hdr_maxsz + 1 + \
104 					 nfs4_xattr_name_maxsz)
105 #define decode_removexattr_maxsz	(op_decode_hdr_maxsz + \
106 					 decode_change_info_maxsz)
107 
108 #define NFS4_enc_allocate_sz		(compound_encode_hdr_maxsz + \
109 					 encode_sequence_maxsz + \
110 					 encode_putfh_maxsz + \
111 					 encode_allocate_maxsz + \
112 					 encode_getattr_maxsz)
113 #define NFS4_dec_allocate_sz		(compound_decode_hdr_maxsz + \
114 					 decode_sequence_maxsz + \
115 					 decode_putfh_maxsz + \
116 					 decode_allocate_maxsz + \
117 					 decode_getattr_maxsz)
118 #define NFS4_enc_copy_sz		(compound_encode_hdr_maxsz + \
119 					 encode_sequence_maxsz + \
120 					 encode_putfh_maxsz + \
121 					 encode_savefh_maxsz + \
122 					 encode_putfh_maxsz + \
123 					 encode_copy_maxsz + \
124 					 encode_commit_maxsz)
125 #define NFS4_dec_copy_sz		(compound_decode_hdr_maxsz + \
126 					 decode_sequence_maxsz + \
127 					 decode_putfh_maxsz + \
128 					 decode_savefh_maxsz + \
129 					 decode_putfh_maxsz + \
130 					 decode_copy_maxsz + \
131 					 decode_commit_maxsz)
132 #define NFS4_enc_offload_cancel_sz	(compound_encode_hdr_maxsz + \
133 					 encode_sequence_maxsz + \
134 					 encode_putfh_maxsz + \
135 					 encode_offload_cancel_maxsz)
136 #define NFS4_dec_offload_cancel_sz	(compound_decode_hdr_maxsz + \
137 					 decode_sequence_maxsz + \
138 					 decode_putfh_maxsz + \
139 					 decode_offload_cancel_maxsz)
140 #define NFS4_enc_copy_notify_sz		(compound_encode_hdr_maxsz + \
141 					 encode_putfh_maxsz + \
142 					 encode_copy_notify_maxsz)
143 #define NFS4_dec_copy_notify_sz		(compound_decode_hdr_maxsz + \
144 					 decode_putfh_maxsz + \
145 					 decode_copy_notify_maxsz)
146 #define NFS4_enc_deallocate_sz		(compound_encode_hdr_maxsz + \
147 					 encode_sequence_maxsz + \
148 					 encode_putfh_maxsz + \
149 					 encode_deallocate_maxsz + \
150 					 encode_getattr_maxsz)
151 #define NFS4_dec_deallocate_sz		(compound_decode_hdr_maxsz + \
152 					 decode_sequence_maxsz + \
153 					 decode_putfh_maxsz + \
154 					 decode_deallocate_maxsz + \
155 					 decode_getattr_maxsz)
156 #define NFS4_enc_read_plus_sz		(compound_encode_hdr_maxsz + \
157 					 encode_sequence_maxsz + \
158 					 encode_putfh_maxsz + \
159 					 encode_read_plus_maxsz)
160 #define NFS4_dec_read_plus_sz		(compound_decode_hdr_maxsz + \
161 					 decode_sequence_maxsz + \
162 					 decode_putfh_maxsz + \
163 					 decode_read_plus_maxsz)
164 #define NFS4_enc_seek_sz		(compound_encode_hdr_maxsz + \
165 					 encode_sequence_maxsz + \
166 					 encode_putfh_maxsz + \
167 					 encode_seek_maxsz)
168 #define NFS4_dec_seek_sz		(compound_decode_hdr_maxsz + \
169 					 decode_sequence_maxsz + \
170 					 decode_putfh_maxsz + \
171 					 decode_seek_maxsz)
172 #define NFS4_enc_layoutstats_sz		(compound_encode_hdr_maxsz + \
173 					 encode_sequence_maxsz + \
174 					 encode_putfh_maxsz + \
175 					 PNFS_LAYOUTSTATS_MAXDEV * encode_layoutstats_maxsz)
176 #define NFS4_dec_layoutstats_sz		(compound_decode_hdr_maxsz + \
177 					 decode_sequence_maxsz + \
178 					 decode_putfh_maxsz + \
179 					 PNFS_LAYOUTSTATS_MAXDEV * decode_layoutstats_maxsz)
180 #define NFS4_enc_layouterror_sz		(compound_encode_hdr_maxsz + \
181 					 encode_sequence_maxsz + \
182 					 encode_putfh_maxsz + \
183 					 NFS42_LAYOUTERROR_MAX * \
184 					 encode_layouterror_maxsz)
185 #define NFS4_dec_layouterror_sz		(compound_decode_hdr_maxsz + \
186 					 decode_sequence_maxsz + \
187 					 decode_putfh_maxsz + \
188 					 NFS42_LAYOUTERROR_MAX * \
189 					 decode_layouterror_maxsz)
190 #define NFS4_enc_clone_sz		(compound_encode_hdr_maxsz + \
191 					 encode_sequence_maxsz + \
192 					 encode_putfh_maxsz + \
193 					 encode_savefh_maxsz + \
194 					 encode_putfh_maxsz + \
195 					 encode_clone_maxsz + \
196 					 encode_getattr_maxsz)
197 #define NFS4_dec_clone_sz		(compound_decode_hdr_maxsz + \
198 					 decode_sequence_maxsz + \
199 					 decode_putfh_maxsz + \
200 					 decode_savefh_maxsz + \
201 					 decode_putfh_maxsz + \
202 					 decode_clone_maxsz + \
203 					 decode_getattr_maxsz)
204 #define NFS4_enc_getxattr_sz		(compound_encode_hdr_maxsz + \
205 					 encode_sequence_maxsz + \
206 					 encode_putfh_maxsz + \
207 					 encode_getxattr_maxsz)
208 #define NFS4_dec_getxattr_sz		(compound_decode_hdr_maxsz + \
209 					 decode_sequence_maxsz + \
210 					 decode_putfh_maxsz + \
211 					 decode_getxattr_maxsz)
212 #define NFS4_enc_setxattr_sz		(compound_encode_hdr_maxsz + \
213 					 encode_sequence_maxsz + \
214 					 encode_putfh_maxsz + \
215 					 encode_setxattr_maxsz)
216 #define NFS4_dec_setxattr_sz		(compound_decode_hdr_maxsz + \
217 					 decode_sequence_maxsz + \
218 					 decode_putfh_maxsz + \
219 					 decode_setxattr_maxsz)
220 #define NFS4_enc_listxattrs_sz		(compound_encode_hdr_maxsz + \
221 					 encode_sequence_maxsz + \
222 					 encode_putfh_maxsz + \
223 					 encode_listxattrs_maxsz)
224 #define NFS4_dec_listxattrs_sz		(compound_decode_hdr_maxsz + \
225 					 decode_sequence_maxsz + \
226 					 decode_putfh_maxsz + \
227 					 decode_listxattrs_maxsz)
228 #define NFS4_enc_removexattr_sz		(compound_encode_hdr_maxsz + \
229 					 encode_sequence_maxsz + \
230 					 encode_putfh_maxsz + \
231 					 encode_removexattr_maxsz)
232 #define NFS4_dec_removexattr_sz		(compound_decode_hdr_maxsz + \
233 					 decode_sequence_maxsz + \
234 					 decode_putfh_maxsz + \
235 					 decode_removexattr_maxsz)
236 
237 /*
238  * These values specify the maximum amount of data that is not
239  * associated with the extended attribute name or extended
240  * attribute list in the SETXATTR, GETXATTR and LISTXATTR
241  * respectively.
242  */
243 const u32 nfs42_maxsetxattr_overhead = ((RPC_MAX_HEADER_WITH_AUTH +
244 					compound_encode_hdr_maxsz +
245 					encode_sequence_maxsz +
246 					encode_putfh_maxsz + 1 +
247 					nfs4_xattr_name_maxsz)
248 					* XDR_UNIT);
249 
250 const u32 nfs42_maxgetxattr_overhead = ((RPC_MAX_HEADER_WITH_AUTH +
251 					compound_decode_hdr_maxsz +
252 					decode_sequence_maxsz +
253 					decode_putfh_maxsz + 1) * XDR_UNIT);
254 
255 const u32 nfs42_maxlistxattrs_overhead = ((RPC_MAX_HEADER_WITH_AUTH +
256 					compound_decode_hdr_maxsz +
257 					decode_sequence_maxsz +
258 					decode_putfh_maxsz + 3) * XDR_UNIT);
259 
260 static void encode_fallocate(struct xdr_stream *xdr,
261 			     const struct nfs42_falloc_args *args)
262 {
263 	encode_nfs4_stateid(xdr, &args->falloc_stateid);
264 	encode_uint64(xdr, args->falloc_offset);
265 	encode_uint64(xdr, args->falloc_length);
266 }
267 
268 static void encode_allocate(struct xdr_stream *xdr,
269 			    const struct nfs42_falloc_args *args,
270 			    struct compound_hdr *hdr)
271 {
272 	encode_op_hdr(xdr, OP_ALLOCATE, decode_allocate_maxsz, hdr);
273 	encode_fallocate(xdr, args);
274 }
275 
276 static void encode_nl4_server(struct xdr_stream *xdr,
277 			      const struct nl4_server *ns)
278 {
279 	encode_uint32(xdr, ns->nl4_type);
280 	switch (ns->nl4_type) {
281 	case NL4_NAME:
282 	case NL4_URL:
283 		encode_string(xdr, ns->u.nl4_str_sz, ns->u.nl4_str);
284 		break;
285 	case NL4_NETADDR:
286 		encode_string(xdr, ns->u.nl4_addr.netid_len,
287 			      ns->u.nl4_addr.netid);
288 		encode_string(xdr, ns->u.nl4_addr.addr_len,
289 			      ns->u.nl4_addr.addr);
290 		break;
291 	default:
292 		WARN_ON_ONCE(1);
293 	}
294 }
295 
296 static void encode_copy(struct xdr_stream *xdr,
297 			const struct nfs42_copy_args *args,
298 			struct compound_hdr *hdr)
299 {
300 	encode_op_hdr(xdr, OP_COPY, decode_copy_maxsz, hdr);
301 	encode_nfs4_stateid(xdr, &args->src_stateid);
302 	encode_nfs4_stateid(xdr, &args->dst_stateid);
303 
304 	encode_uint64(xdr, args->src_pos);
305 	encode_uint64(xdr, args->dst_pos);
306 	encode_uint64(xdr, args->count);
307 
308 	encode_uint32(xdr, 1); /* consecutive = true */
309 	encode_uint32(xdr, args->sync);
310 	if (args->cp_src == NULL) { /* intra-ssc */
311 		encode_uint32(xdr, 0); /* no src server list */
312 		return;
313 	}
314 	encode_uint32(xdr, 1); /* supporting 1 server */
315 	encode_nl4_server(xdr, args->cp_src);
316 }
317 
318 static void encode_copy_commit(struct xdr_stream *xdr,
319 			  const struct nfs42_copy_args *args,
320 			  struct compound_hdr *hdr)
321 {
322 	__be32 *p;
323 
324 	encode_op_hdr(xdr, OP_COMMIT, decode_commit_maxsz, hdr);
325 	p = reserve_space(xdr, 12);
326 	p = xdr_encode_hyper(p, args->dst_pos);
327 	*p = cpu_to_be32(args->count);
328 }
329 
330 static void encode_offload_cancel(struct xdr_stream *xdr,
331 				  const struct nfs42_offload_status_args *args,
332 				  struct compound_hdr *hdr)
333 {
334 	encode_op_hdr(xdr, OP_OFFLOAD_CANCEL, decode_offload_cancel_maxsz, hdr);
335 	encode_nfs4_stateid(xdr, &args->osa_stateid);
336 }
337 
338 static void encode_copy_notify(struct xdr_stream *xdr,
339 			       const struct nfs42_copy_notify_args *args,
340 			       struct compound_hdr *hdr)
341 {
342 	encode_op_hdr(xdr, OP_COPY_NOTIFY, decode_copy_notify_maxsz, hdr);
343 	encode_nfs4_stateid(xdr, &args->cna_src_stateid);
344 	encode_nl4_server(xdr, &args->cna_dst);
345 }
346 
347 static void encode_deallocate(struct xdr_stream *xdr,
348 			      const struct nfs42_falloc_args *args,
349 			      struct compound_hdr *hdr)
350 {
351 	encode_op_hdr(xdr, OP_DEALLOCATE, decode_deallocate_maxsz, hdr);
352 	encode_fallocate(xdr, args);
353 }
354 
355 static void encode_read_plus(struct xdr_stream *xdr,
356 			     const struct nfs_pgio_args *args,
357 			     struct compound_hdr *hdr)
358 {
359 	encode_op_hdr(xdr, OP_READ_PLUS, decode_read_plus_maxsz, hdr);
360 	encode_nfs4_stateid(xdr, &args->stateid);
361 	encode_uint64(xdr, args->offset);
362 	encode_uint32(xdr, args->count);
363 }
364 
365 static void encode_seek(struct xdr_stream *xdr,
366 			const struct nfs42_seek_args *args,
367 			struct compound_hdr *hdr)
368 {
369 	encode_op_hdr(xdr, OP_SEEK, decode_seek_maxsz, hdr);
370 	encode_nfs4_stateid(xdr, &args->sa_stateid);
371 	encode_uint64(xdr, args->sa_offset);
372 	encode_uint32(xdr, args->sa_what);
373 }
374 
375 static void encode_layoutstats(struct xdr_stream *xdr,
376 			       const struct nfs42_layoutstat_args *args,
377 			       struct nfs42_layoutstat_devinfo *devinfo,
378 			       struct compound_hdr *hdr)
379 {
380 	__be32 *p;
381 
382 	encode_op_hdr(xdr, OP_LAYOUTSTATS, decode_layoutstats_maxsz, hdr);
383 	p = reserve_space(xdr, 8 + 8);
384 	p = xdr_encode_hyper(p, devinfo->offset);
385 	p = xdr_encode_hyper(p, devinfo->length);
386 	encode_nfs4_stateid(xdr, &args->stateid);
387 	p = reserve_space(xdr, 4*8 + NFS4_DEVICEID4_SIZE + 4);
388 	p = xdr_encode_hyper(p, devinfo->read_count);
389 	p = xdr_encode_hyper(p, devinfo->read_bytes);
390 	p = xdr_encode_hyper(p, devinfo->write_count);
391 	p = xdr_encode_hyper(p, devinfo->write_bytes);
392 	p = xdr_encode_opaque_fixed(p, devinfo->dev_id.data,
393 			NFS4_DEVICEID4_SIZE);
394 	/* Encode layoutupdate4 */
395 	*p++ = cpu_to_be32(devinfo->layout_type);
396 	if (devinfo->ld_private.ops)
397 		devinfo->ld_private.ops->encode(xdr, args,
398 				&devinfo->ld_private);
399 	else
400 		encode_uint32(xdr, 0);
401 }
402 
403 static void encode_clone(struct xdr_stream *xdr,
404 			 const struct nfs42_clone_args *args,
405 			 struct compound_hdr *hdr)
406 {
407 	__be32 *p;
408 
409 	encode_op_hdr(xdr, OP_CLONE, decode_clone_maxsz, hdr);
410 	encode_nfs4_stateid(xdr, &args->src_stateid);
411 	encode_nfs4_stateid(xdr, &args->dst_stateid);
412 	p = reserve_space(xdr, 3*8);
413 	p = xdr_encode_hyper(p, args->src_offset);
414 	p = xdr_encode_hyper(p, args->dst_offset);
415 	xdr_encode_hyper(p, args->count);
416 }
417 
418 static void encode_device_error(struct xdr_stream *xdr,
419 				const struct nfs42_device_error *error)
420 {
421 	__be32 *p;
422 
423 	p = reserve_space(xdr, NFS4_DEVICEID4_SIZE + 2*4);
424 	p = xdr_encode_opaque_fixed(p, error->dev_id.data,
425 			NFS4_DEVICEID4_SIZE);
426 	*p++ = cpu_to_be32(error->status);
427 	*p = cpu_to_be32(error->opnum);
428 }
429 
430 static void encode_layouterror(struct xdr_stream *xdr,
431 			       const struct nfs42_layout_error *args,
432 			       struct compound_hdr *hdr)
433 {
434 	__be32 *p;
435 
436 	encode_op_hdr(xdr, OP_LAYOUTERROR, decode_layouterror_maxsz, hdr);
437 	p = reserve_space(xdr, 8 + 8);
438 	p = xdr_encode_hyper(p, args->offset);
439 	p = xdr_encode_hyper(p, args->length);
440 	encode_nfs4_stateid(xdr, &args->stateid);
441 	p = reserve_space(xdr, 4);
442 	*p = cpu_to_be32(1);
443 	encode_device_error(xdr, &args->errors[0]);
444 }
445 
446 static void encode_setxattr(struct xdr_stream *xdr,
447 			    const struct nfs42_setxattrargs *arg,
448 			    struct compound_hdr *hdr)
449 {
450 	__be32 *p;
451 
452 	BUILD_BUG_ON(XATTR_CREATE != SETXATTR4_CREATE);
453 	BUILD_BUG_ON(XATTR_REPLACE != SETXATTR4_REPLACE);
454 
455 	encode_op_hdr(xdr, OP_SETXATTR, decode_setxattr_maxsz, hdr);
456 	p = reserve_space(xdr, 4);
457 	*p = cpu_to_be32(arg->xattr_flags);
458 	encode_string(xdr, strlen(arg->xattr_name), arg->xattr_name);
459 	p = reserve_space(xdr, 4);
460 	*p = cpu_to_be32(arg->xattr_len);
461 	if (arg->xattr_len)
462 		xdr_write_pages(xdr, arg->xattr_pages, 0, arg->xattr_len);
463 }
464 
465 static void encode_getxattr(struct xdr_stream *xdr, const char *name,
466 			    struct compound_hdr *hdr)
467 {
468 	encode_op_hdr(xdr, OP_GETXATTR, decode_getxattr_maxsz, hdr);
469 	encode_string(xdr, strlen(name), name);
470 }
471 
472 static void encode_removexattr(struct xdr_stream *xdr, const char *name,
473 			       struct compound_hdr *hdr)
474 {
475 	encode_op_hdr(xdr, OP_REMOVEXATTR, decode_removexattr_maxsz, hdr);
476 	encode_string(xdr, strlen(name), name);
477 }
478 
479 static void encode_listxattrs(struct xdr_stream *xdr,
480 			     const struct nfs42_listxattrsargs *arg,
481 			     struct compound_hdr *hdr)
482 {
483 	__be32 *p;
484 
485 	encode_op_hdr(xdr, OP_LISTXATTRS, decode_listxattrs_maxsz, hdr);
486 
487 	p = reserve_space(xdr, 12);
488 	if (unlikely(!p))
489 		return;
490 
491 	p = xdr_encode_hyper(p, arg->cookie);
492 	/*
493 	 * RFC 8276 says to specify the full max length of the LISTXATTRS
494 	 * XDR reply. Count is set to the XDR length of the names array
495 	 * plus the EOF marker. So, add the cookie and the names count.
496 	 */
497 	*p = cpu_to_be32(arg->count + 8 + 4);
498 }
499 
500 /*
501  * Encode ALLOCATE request
502  */
503 static void nfs4_xdr_enc_allocate(struct rpc_rqst *req,
504 				  struct xdr_stream *xdr,
505 				  const void *data)
506 {
507 	const struct nfs42_falloc_args *args = data;
508 	struct compound_hdr hdr = {
509 		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
510 	};
511 
512 	encode_compound_hdr(xdr, req, &hdr);
513 	encode_sequence(xdr, &args->seq_args, &hdr);
514 	encode_putfh(xdr, args->falloc_fh, &hdr);
515 	encode_allocate(xdr, args, &hdr);
516 	encode_getfattr(xdr, args->falloc_bitmask, &hdr);
517 	encode_nops(&hdr);
518 }
519 
520 /*
521  * Encode COPY request
522  */
523 static void nfs4_xdr_enc_copy(struct rpc_rqst *req,
524 			      struct xdr_stream *xdr,
525 			      const void *data)
526 {
527 	const struct nfs42_copy_args *args = data;
528 	struct compound_hdr hdr = {
529 		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
530 	};
531 
532 	encode_compound_hdr(xdr, req, &hdr);
533 	encode_sequence(xdr, &args->seq_args, &hdr);
534 	encode_putfh(xdr, args->src_fh, &hdr);
535 	encode_savefh(xdr, &hdr);
536 	encode_putfh(xdr, args->dst_fh, &hdr);
537 	encode_copy(xdr, args, &hdr);
538 	if (args->sync)
539 		encode_copy_commit(xdr, args, &hdr);
540 	encode_nops(&hdr);
541 }
542 
543 /*
544  * Encode OFFLOAD_CANEL request
545  */
546 static void nfs4_xdr_enc_offload_cancel(struct rpc_rqst *req,
547 					struct xdr_stream *xdr,
548 					const void *data)
549 {
550 	const struct nfs42_offload_status_args *args = data;
551 	struct compound_hdr hdr = {
552 		.minorversion = nfs4_xdr_minorversion(&args->osa_seq_args),
553 	};
554 
555 	encode_compound_hdr(xdr, req, &hdr);
556 	encode_sequence(xdr, &args->osa_seq_args, &hdr);
557 	encode_putfh(xdr, args->osa_src_fh, &hdr);
558 	encode_offload_cancel(xdr, args, &hdr);
559 	encode_nops(&hdr);
560 }
561 
562 /*
563  * Encode COPY_NOTIFY request
564  */
565 static void nfs4_xdr_enc_copy_notify(struct rpc_rqst *req,
566 				     struct xdr_stream *xdr,
567 				     const void *data)
568 {
569 	const struct nfs42_copy_notify_args *args = data;
570 	struct compound_hdr hdr = {
571 		.minorversion = nfs4_xdr_minorversion(&args->cna_seq_args),
572 	};
573 
574 	encode_compound_hdr(xdr, req, &hdr);
575 	encode_sequence(xdr, &args->cna_seq_args, &hdr);
576 	encode_putfh(xdr, args->cna_src_fh, &hdr);
577 	encode_copy_notify(xdr, args, &hdr);
578 	encode_nops(&hdr);
579 }
580 
581 /*
582  * Encode DEALLOCATE request
583  */
584 static void nfs4_xdr_enc_deallocate(struct rpc_rqst *req,
585 				    struct xdr_stream *xdr,
586 				    const void *data)
587 {
588 	const struct nfs42_falloc_args *args = data;
589 	struct compound_hdr hdr = {
590 		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
591 	};
592 
593 	encode_compound_hdr(xdr, req, &hdr);
594 	encode_sequence(xdr, &args->seq_args, &hdr);
595 	encode_putfh(xdr, args->falloc_fh, &hdr);
596 	encode_deallocate(xdr, args, &hdr);
597 	encode_getfattr(xdr, args->falloc_bitmask, &hdr);
598 	encode_nops(&hdr);
599 }
600 
601 /*
602  * Encode READ_PLUS request
603  */
604 static void nfs4_xdr_enc_read_plus(struct rpc_rqst *req,
605 				   struct xdr_stream *xdr,
606 				   const void *data)
607 {
608 	const struct nfs_pgio_args *args = data;
609 	struct compound_hdr hdr = {
610 		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
611 	};
612 
613 	encode_compound_hdr(xdr, req, &hdr);
614 	encode_sequence(xdr, &args->seq_args, &hdr);
615 	encode_putfh(xdr, args->fh, &hdr);
616 	encode_read_plus(xdr, args, &hdr);
617 
618 	rpc_prepare_reply_pages(req, args->pages, args->pgbase,
619 				args->count, hdr.replen);
620 	encode_nops(&hdr);
621 }
622 
623 /*
624  * Encode SEEK request
625  */
626 static void nfs4_xdr_enc_seek(struct rpc_rqst *req,
627 			      struct xdr_stream *xdr,
628 			      const void *data)
629 {
630 	const struct nfs42_seek_args *args = data;
631 	struct compound_hdr hdr = {
632 		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
633 	};
634 
635 	encode_compound_hdr(xdr, req, &hdr);
636 	encode_sequence(xdr, &args->seq_args, &hdr);
637 	encode_putfh(xdr, args->sa_fh, &hdr);
638 	encode_seek(xdr, args, &hdr);
639 	encode_nops(&hdr);
640 }
641 
642 /*
643  * Encode LAYOUTSTATS request
644  */
645 static void nfs4_xdr_enc_layoutstats(struct rpc_rqst *req,
646 				     struct xdr_stream *xdr,
647 				     const void *data)
648 {
649 	const struct nfs42_layoutstat_args *args = data;
650 	int i;
651 
652 	struct compound_hdr hdr = {
653 		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
654 	};
655 
656 	encode_compound_hdr(xdr, req, &hdr);
657 	encode_sequence(xdr, &args->seq_args, &hdr);
658 	encode_putfh(xdr, args->fh, &hdr);
659 	WARN_ON(args->num_dev > PNFS_LAYOUTSTATS_MAXDEV);
660 	for (i = 0; i < args->num_dev; i++)
661 		encode_layoutstats(xdr, args, &args->devinfo[i], &hdr);
662 	encode_nops(&hdr);
663 }
664 
665 /*
666  * Encode CLONE request
667  */
668 static void nfs4_xdr_enc_clone(struct rpc_rqst *req,
669 			       struct xdr_stream *xdr,
670 			       const void *data)
671 {
672 	const struct nfs42_clone_args *args = data;
673 	struct compound_hdr hdr = {
674 		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
675 	};
676 
677 	encode_compound_hdr(xdr, req, &hdr);
678 	encode_sequence(xdr, &args->seq_args, &hdr);
679 	encode_putfh(xdr, args->src_fh, &hdr);
680 	encode_savefh(xdr, &hdr);
681 	encode_putfh(xdr, args->dst_fh, &hdr);
682 	encode_clone(xdr, args, &hdr);
683 	encode_getfattr(xdr, args->dst_bitmask, &hdr);
684 	encode_nops(&hdr);
685 }
686 
687 /*
688  * Encode LAYOUTERROR request
689  */
690 static void nfs4_xdr_enc_layouterror(struct rpc_rqst *req,
691 				     struct xdr_stream *xdr,
692 				     const void *data)
693 {
694 	const struct nfs42_layouterror_args *args = data;
695 	struct compound_hdr hdr = {
696 		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
697 	};
698 	int i;
699 
700 	encode_compound_hdr(xdr, req, &hdr);
701 	encode_sequence(xdr, &args->seq_args, &hdr);
702 	encode_putfh(xdr, NFS_FH(args->inode), &hdr);
703 	for (i = 0; i < args->num_errors; i++)
704 		encode_layouterror(xdr, &args->errors[i], &hdr);
705 	encode_nops(&hdr);
706 }
707 
708 /*
709  * Encode SETXATTR request
710  */
711 static void nfs4_xdr_enc_setxattr(struct rpc_rqst *req, struct xdr_stream *xdr,
712 				  const void *data)
713 {
714 	const struct nfs42_setxattrargs *args = data;
715 	struct compound_hdr hdr = {
716 		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
717 	};
718 
719 	encode_compound_hdr(xdr, req, &hdr);
720 	encode_sequence(xdr, &args->seq_args, &hdr);
721 	encode_putfh(xdr, args->fh, &hdr);
722 	encode_setxattr(xdr, args, &hdr);
723 	encode_nops(&hdr);
724 }
725 
726 /*
727  * Encode GETXATTR request
728  */
729 static void nfs4_xdr_enc_getxattr(struct rpc_rqst *req, struct xdr_stream *xdr,
730 				  const void *data)
731 {
732 	const struct nfs42_getxattrargs *args = data;
733 	struct compound_hdr hdr = {
734 		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
735 	};
736 	uint32_t replen;
737 
738 	encode_compound_hdr(xdr, req, &hdr);
739 	encode_sequence(xdr, &args->seq_args, &hdr);
740 	encode_putfh(xdr, args->fh, &hdr);
741 	replen = hdr.replen + op_decode_hdr_maxsz + 1;
742 	encode_getxattr(xdr, args->xattr_name, &hdr);
743 
744 	rpc_prepare_reply_pages(req, args->xattr_pages, 0, args->xattr_len,
745 				replen);
746 
747 	encode_nops(&hdr);
748 }
749 
750 /*
751  * Encode LISTXATTR request
752  */
753 static void nfs4_xdr_enc_listxattrs(struct rpc_rqst *req,
754 				    struct xdr_stream *xdr, const void *data)
755 {
756 	const struct nfs42_listxattrsargs *args = data;
757 	struct compound_hdr hdr = {
758 		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
759 	};
760 	uint32_t replen;
761 
762 	encode_compound_hdr(xdr, req, &hdr);
763 	encode_sequence(xdr, &args->seq_args, &hdr);
764 	encode_putfh(xdr, args->fh, &hdr);
765 	replen = hdr.replen + op_decode_hdr_maxsz + 2 + 1;
766 	encode_listxattrs(xdr, args, &hdr);
767 
768 	rpc_prepare_reply_pages(req, args->xattr_pages, 0, args->count, replen);
769 
770 	encode_nops(&hdr);
771 }
772 
773 /*
774  * Encode REMOVEXATTR request
775  */
776 static void nfs4_xdr_enc_removexattr(struct rpc_rqst *req,
777 				     struct xdr_stream *xdr, const void *data)
778 {
779 	const struct nfs42_removexattrargs *args = data;
780 	struct compound_hdr hdr = {
781 		.minorversion = nfs4_xdr_minorversion(&args->seq_args),
782 	};
783 
784 	encode_compound_hdr(xdr, req, &hdr);
785 	encode_sequence(xdr, &args->seq_args, &hdr);
786 	encode_putfh(xdr, args->fh, &hdr);
787 	encode_removexattr(xdr, args->xattr_name, &hdr);
788 	encode_nops(&hdr);
789 }
790 
791 static int decode_allocate(struct xdr_stream *xdr, struct nfs42_falloc_res *res)
792 {
793 	return decode_op_hdr(xdr, OP_ALLOCATE);
794 }
795 
796 static int decode_write_response(struct xdr_stream *xdr,
797 				 struct nfs42_write_res *res)
798 {
799 	__be32 *p;
800 	int status, count;
801 
802 	p = xdr_inline_decode(xdr, 4);
803 	if (unlikely(!p))
804 		return -EIO;
805 	count = be32_to_cpup(p);
806 	if (count > 1)
807 		return -EREMOTEIO;
808 	else if (count == 1) {
809 		status = decode_opaque_fixed(xdr, &res->stateid,
810 				NFS4_STATEID_SIZE);
811 		if (unlikely(status))
812 			return -EIO;
813 	}
814 	p = xdr_inline_decode(xdr, 8 + 4);
815 	if (unlikely(!p))
816 		return -EIO;
817 	p = xdr_decode_hyper(p, &res->count);
818 	res->verifier.committed = be32_to_cpup(p);
819 	return decode_verifier(xdr, &res->verifier.verifier);
820 }
821 
822 static int decode_nl4_server(struct xdr_stream *xdr, struct nl4_server *ns)
823 {
824 	struct nfs42_netaddr *naddr;
825 	uint32_t dummy;
826 	char *dummy_str;
827 	__be32 *p;
828 	int status;
829 
830 	/* nl_type */
831 	p = xdr_inline_decode(xdr, 4);
832 	if (unlikely(!p))
833 		return -EIO;
834 	ns->nl4_type = be32_to_cpup(p);
835 	switch (ns->nl4_type) {
836 	case NL4_NAME:
837 	case NL4_URL:
838 		status = decode_opaque_inline(xdr, &dummy, &dummy_str);
839 		if (unlikely(status))
840 			return status;
841 		if (unlikely(dummy > NFS4_OPAQUE_LIMIT))
842 			return -EIO;
843 		memcpy(&ns->u.nl4_str, dummy_str, dummy);
844 		ns->u.nl4_str_sz = dummy;
845 		break;
846 	case NL4_NETADDR:
847 		naddr = &ns->u.nl4_addr;
848 
849 		/* netid string */
850 		status = decode_opaque_inline(xdr, &dummy, &dummy_str);
851 		if (unlikely(status))
852 			return status;
853 		if (unlikely(dummy > RPCBIND_MAXNETIDLEN))
854 			return -EIO;
855 		naddr->netid_len = dummy;
856 		memcpy(naddr->netid, dummy_str, naddr->netid_len);
857 
858 		/* uaddr string */
859 		status = decode_opaque_inline(xdr, &dummy, &dummy_str);
860 		if (unlikely(status))
861 			return status;
862 		if (unlikely(dummy > RPCBIND_MAXUADDRLEN))
863 			return -EIO;
864 		naddr->addr_len = dummy;
865 		memcpy(naddr->addr, dummy_str, naddr->addr_len);
866 		break;
867 	default:
868 		WARN_ON_ONCE(1);
869 		return -EIO;
870 	}
871 	return 0;
872 }
873 
874 static int decode_copy_requirements(struct xdr_stream *xdr,
875 				    struct nfs42_copy_res *res) {
876 	__be32 *p;
877 
878 	p = xdr_inline_decode(xdr, 4 + 4);
879 	if (unlikely(!p))
880 		return -EIO;
881 
882 	res->consecutive = be32_to_cpup(p++);
883 	res->synchronous = be32_to_cpup(p++);
884 	return 0;
885 }
886 
887 static int decode_copy(struct xdr_stream *xdr, struct nfs42_copy_res *res)
888 {
889 	int status;
890 
891 	status = decode_op_hdr(xdr, OP_COPY);
892 	if (status == NFS4ERR_OFFLOAD_NO_REQS) {
893 		status = decode_copy_requirements(xdr, res);
894 		if (status)
895 			return status;
896 		return NFS4ERR_OFFLOAD_NO_REQS;
897 	} else if (status)
898 		return status;
899 
900 	status = decode_write_response(xdr, &res->write_res);
901 	if (status)
902 		return status;
903 
904 	return decode_copy_requirements(xdr, res);
905 }
906 
907 static int decode_offload_cancel(struct xdr_stream *xdr,
908 				 struct nfs42_offload_status_res *res)
909 {
910 	return decode_op_hdr(xdr, OP_OFFLOAD_CANCEL);
911 }
912 
913 static int decode_copy_notify(struct xdr_stream *xdr,
914 			      struct nfs42_copy_notify_res *res)
915 {
916 	__be32 *p;
917 	int status, count;
918 
919 	status = decode_op_hdr(xdr, OP_COPY_NOTIFY);
920 	if (status)
921 		return status;
922 	/* cnr_lease_time */
923 	p = xdr_inline_decode(xdr, 12);
924 	if (unlikely(!p))
925 		return -EIO;
926 	p = xdr_decode_hyper(p, &res->cnr_lease_time.seconds);
927 	res->cnr_lease_time.nseconds = be32_to_cpup(p);
928 
929 	status = decode_opaque_fixed(xdr, &res->cnr_stateid, NFS4_STATEID_SIZE);
930 	if (unlikely(status))
931 		return -EIO;
932 
933 	/* number of source addresses */
934 	p = xdr_inline_decode(xdr, 4);
935 	if (unlikely(!p))
936 		return -EIO;
937 
938 	count = be32_to_cpup(p);
939 	if (count > 1)
940 		pr_warn("NFS: %s: nsvr %d > Supported. Use first servers\n",
941 			 __func__, count);
942 
943 	status = decode_nl4_server(xdr, &res->cnr_src);
944 	if (unlikely(status))
945 		return -EIO;
946 	return 0;
947 }
948 
949 static int decode_deallocate(struct xdr_stream *xdr, struct nfs42_falloc_res *res)
950 {
951 	return decode_op_hdr(xdr, OP_DEALLOCATE);
952 }
953 
954 struct read_plus_segment {
955 	enum data_content4 type;
956 	uint64_t offset;
957 	union {
958 		struct {
959 			uint64_t length;
960 		} hole;
961 
962 		struct {
963 			uint32_t length;
964 			unsigned int from;
965 		} data;
966 	};
967 };
968 
969 static inline uint64_t read_plus_segment_length(struct read_plus_segment *seg)
970 {
971 	return seg->type == NFS4_CONTENT_DATA ? seg->data.length : seg->hole.length;
972 }
973 
974 static int decode_read_plus_segment(struct xdr_stream *xdr,
975 				    struct read_plus_segment *seg)
976 {
977 	__be32 *p;
978 
979 	p = xdr_inline_decode(xdr, 4);
980 	if (!p)
981 		return -EIO;
982 	seg->type = be32_to_cpup(p++);
983 
984 	p = xdr_inline_decode(xdr, seg->type == NFS4_CONTENT_DATA ? 12 : 16);
985 	if (!p)
986 		return -EIO;
987 	p = xdr_decode_hyper(p, &seg->offset);
988 
989 	if (seg->type == NFS4_CONTENT_DATA) {
990 		struct xdr_buf buf;
991 		uint32_t len = be32_to_cpup(p);
992 
993 		seg->data.length = len;
994 		seg->data.from = xdr_stream_pos(xdr);
995 
996 		if (!xdr_stream_subsegment(xdr, &buf, xdr_align_size(len)))
997 			return -EIO;
998 	} else if (seg->type == NFS4_CONTENT_HOLE) {
999 		xdr_decode_hyper(p, &seg->hole.length);
1000 	} else
1001 		return -EINVAL;
1002 	return 0;
1003 }
1004 
1005 static int process_read_plus_segment(struct xdr_stream *xdr,
1006 				     struct nfs_pgio_args *args,
1007 				     struct nfs_pgio_res *res,
1008 				     struct read_plus_segment *seg)
1009 {
1010 	unsigned long offset = seg->offset;
1011 	unsigned long length = read_plus_segment_length(seg);
1012 	unsigned int bufpos;
1013 
1014 	if (offset + length < args->offset)
1015 		return 0;
1016 	else if (offset > args->offset + args->count) {
1017 		res->eof = 0;
1018 		return 0;
1019 	} else if (offset < args->offset) {
1020 		length -= (args->offset - offset);
1021 		offset = args->offset;
1022 	} else if (offset + length > args->offset + args->count) {
1023 		length = (args->offset + args->count) - offset;
1024 		res->eof = 0;
1025 	}
1026 
1027 	bufpos = xdr->buf->head[0].iov_len + (offset - args->offset);
1028 	if (seg->type == NFS4_CONTENT_HOLE)
1029 		return xdr_stream_zero(xdr, bufpos, length);
1030 	else
1031 		return xdr_stream_move_subsegment(xdr, seg->data.from, bufpos, length);
1032 }
1033 
1034 static int decode_read_plus(struct xdr_stream *xdr, struct nfs_pgio_res *res)
1035 {
1036 	struct nfs_pgio_header *hdr =
1037 		container_of(res, struct nfs_pgio_header, res);
1038 	struct nfs_pgio_args *args = &hdr->args;
1039 	uint32_t segments;
1040 	struct read_plus_segment *segs;
1041 	int status, i;
1042 	__be32 *p;
1043 
1044 	status = decode_op_hdr(xdr, OP_READ_PLUS);
1045 	if (status)
1046 		return status;
1047 
1048 	p = xdr_inline_decode(xdr, 4 + 4);
1049 	if (unlikely(!p))
1050 		return -EIO;
1051 
1052 	res->count = 0;
1053 	res->eof = be32_to_cpup(p++);
1054 	segments = be32_to_cpup(p++);
1055 	if (segments == 0)
1056 		return status;
1057 
1058 	segs = kmalloc_array(segments, sizeof(*segs), GFP_KERNEL);
1059 	if (!segs)
1060 		return -ENOMEM;
1061 
1062 	status = -EIO;
1063 	for (i = 0; i < segments; i++) {
1064 		status = decode_read_plus_segment(xdr, &segs[i]);
1065 		if (status < 0)
1066 			goto out;
1067 	}
1068 
1069 	xdr_set_pagelen(xdr, xdr_align_size(args->count));
1070 	for (i = segments; i > 0; i--)
1071 		res->count += process_read_plus_segment(xdr, args, res, &segs[i-1]);
1072 	status = 0;
1073 
1074 out:
1075 	kfree(segs);
1076 	return status;
1077 }
1078 
1079 static int decode_seek(struct xdr_stream *xdr, struct nfs42_seek_res *res)
1080 {
1081 	int status;
1082 	__be32 *p;
1083 
1084 	status = decode_op_hdr(xdr, OP_SEEK);
1085 	if (status)
1086 		return status;
1087 
1088 	p = xdr_inline_decode(xdr, 4 + 8);
1089 	if (unlikely(!p))
1090 		return -EIO;
1091 
1092 	res->sr_eof = be32_to_cpup(p++);
1093 	p = xdr_decode_hyper(p, &res->sr_offset);
1094 	return 0;
1095 }
1096 
1097 static int decode_layoutstats(struct xdr_stream *xdr)
1098 {
1099 	return decode_op_hdr(xdr, OP_LAYOUTSTATS);
1100 }
1101 
1102 static int decode_clone(struct xdr_stream *xdr)
1103 {
1104 	return decode_op_hdr(xdr, OP_CLONE);
1105 }
1106 
1107 static int decode_layouterror(struct xdr_stream *xdr)
1108 {
1109 	return decode_op_hdr(xdr, OP_LAYOUTERROR);
1110 }
1111 
1112 static int decode_setxattr(struct xdr_stream *xdr,
1113 			   struct nfs4_change_info *cinfo)
1114 {
1115 	int status;
1116 
1117 	status = decode_op_hdr(xdr, OP_SETXATTR);
1118 	if (status)
1119 		goto out;
1120 	status = decode_change_info(xdr, cinfo);
1121 out:
1122 	return status;
1123 }
1124 
1125 static int decode_getxattr(struct xdr_stream *xdr,
1126 			   struct nfs42_getxattrres *res,
1127 			   struct rpc_rqst *req)
1128 {
1129 	int status;
1130 	__be32 *p;
1131 	u32 len, rdlen;
1132 
1133 	status = decode_op_hdr(xdr, OP_GETXATTR);
1134 	if (status)
1135 		return status;
1136 
1137 	p = xdr_inline_decode(xdr, 4);
1138 	if (unlikely(!p))
1139 		return -EIO;
1140 
1141 	len = be32_to_cpup(p);
1142 
1143 	/*
1144 	 * Only check against the page length here. The actual
1145 	 * requested length may be smaller, but that is only
1146 	 * checked against after possibly caching a valid reply.
1147 	 */
1148 	if (len > req->rq_rcv_buf.page_len)
1149 		return -ERANGE;
1150 
1151 	res->xattr_len = len;
1152 
1153 	if (len > 0) {
1154 		rdlen = xdr_read_pages(xdr, len);
1155 		if (rdlen < len)
1156 			return -EIO;
1157 	}
1158 
1159 	return 0;
1160 }
1161 
1162 static int decode_removexattr(struct xdr_stream *xdr,
1163 			   struct nfs4_change_info *cinfo)
1164 {
1165 	int status;
1166 
1167 	status = decode_op_hdr(xdr, OP_REMOVEXATTR);
1168 	if (status)
1169 		goto out;
1170 
1171 	status = decode_change_info(xdr, cinfo);
1172 out:
1173 	return status;
1174 }
1175 
1176 static int decode_listxattrs(struct xdr_stream *xdr,
1177 			    struct nfs42_listxattrsres *res)
1178 {
1179 	int status;
1180 	__be32 *p;
1181 	u32 count, len, ulen;
1182 	size_t left, copied;
1183 	char *buf;
1184 
1185 	status = decode_op_hdr(xdr, OP_LISTXATTRS);
1186 	if (status) {
1187 		/*
1188 		 * Special case: for LISTXATTRS, NFS4ERR_TOOSMALL
1189 		 * should be translated to ERANGE.
1190 		 */
1191 		if (status == -ETOOSMALL)
1192 			status = -ERANGE;
1193 		/*
1194 		 * Special case: for LISTXATTRS, NFS4ERR_NOXATTR
1195 		 * should be translated to success with zero-length reply.
1196 		 */
1197 		if (status == -ENODATA) {
1198 			res->eof = true;
1199 			status = 0;
1200 		}
1201 		goto out;
1202 	}
1203 
1204 	p = xdr_inline_decode(xdr, 8);
1205 	if (unlikely(!p))
1206 		return -EIO;
1207 
1208 	xdr_decode_hyper(p, &res->cookie);
1209 
1210 	p = xdr_inline_decode(xdr, 4);
1211 	if (unlikely(!p))
1212 		return -EIO;
1213 
1214 	left = res->xattr_len;
1215 	buf = res->xattr_buf;
1216 
1217 	count = be32_to_cpup(p);
1218 	copied = 0;
1219 
1220 	/*
1221 	 * We have asked for enough room to encode the maximum number
1222 	 * of possible attribute names, so everything should fit.
1223 	 *
1224 	 * But, don't rely on that assumption. Just decode entries
1225 	 * until they don't fit anymore, just in case the server did
1226 	 * something odd.
1227 	 */
1228 	while (count--) {
1229 		p = xdr_inline_decode(xdr, 4);
1230 		if (unlikely(!p))
1231 			return -EIO;
1232 
1233 		len = be32_to_cpup(p);
1234 		if (len > (XATTR_NAME_MAX - XATTR_USER_PREFIX_LEN)) {
1235 			status = -ERANGE;
1236 			goto out;
1237 		}
1238 
1239 		p = xdr_inline_decode(xdr, len);
1240 		if (unlikely(!p))
1241 			return -EIO;
1242 
1243 		ulen = len + XATTR_USER_PREFIX_LEN + 1;
1244 		if (buf) {
1245 			if (ulen > left) {
1246 				status = -ERANGE;
1247 				goto out;
1248 			}
1249 
1250 			memcpy(buf, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN);
1251 			memcpy(buf + XATTR_USER_PREFIX_LEN, p, len);
1252 
1253 			buf[ulen - 1] = 0;
1254 			buf += ulen;
1255 			left -= ulen;
1256 		}
1257 		copied += ulen;
1258 	}
1259 
1260 	p = xdr_inline_decode(xdr, 4);
1261 	if (unlikely(!p))
1262 		return -EIO;
1263 
1264 	res->eof = be32_to_cpup(p);
1265 	res->copied = copied;
1266 
1267 out:
1268 	if (status == -ERANGE && res->xattr_len == XATTR_LIST_MAX)
1269 		status = -E2BIG;
1270 
1271 	return status;
1272 }
1273 
1274 /*
1275  * Decode ALLOCATE request
1276  */
1277 static int nfs4_xdr_dec_allocate(struct rpc_rqst *rqstp,
1278 				 struct xdr_stream *xdr,
1279 				 void *data)
1280 {
1281 	struct nfs42_falloc_res *res = data;
1282 	struct compound_hdr hdr;
1283 	int status;
1284 
1285 	status = decode_compound_hdr(xdr, &hdr);
1286 	if (status)
1287 		goto out;
1288 	status = decode_sequence(xdr, &res->seq_res, rqstp);
1289 	if (status)
1290 		goto out;
1291 	status = decode_putfh(xdr);
1292 	if (status)
1293 		goto out;
1294 	status = decode_allocate(xdr, res);
1295 	if (status)
1296 		goto out;
1297 	decode_getfattr(xdr, res->falloc_fattr, res->falloc_server);
1298 out:
1299 	return status;
1300 }
1301 
1302 /*
1303  * Decode COPY response
1304  */
1305 static int nfs4_xdr_dec_copy(struct rpc_rqst *rqstp,
1306 			     struct xdr_stream *xdr,
1307 			     void *data)
1308 {
1309 	struct nfs42_copy_res *res = data;
1310 	struct compound_hdr hdr;
1311 	int status;
1312 
1313 	status = decode_compound_hdr(xdr, &hdr);
1314 	if (status)
1315 		goto out;
1316 	status = decode_sequence(xdr, &res->seq_res, rqstp);
1317 	if (status)
1318 		goto out;
1319 	status = decode_putfh(xdr);
1320 	if (status)
1321 		goto out;
1322 	status = decode_savefh(xdr);
1323 	if (status)
1324 		goto out;
1325 	status = decode_putfh(xdr);
1326 	if (status)
1327 		goto out;
1328 	status = decode_copy(xdr, res);
1329 	if (status)
1330 		goto out;
1331 	if (res->commit_res.verf)
1332 		status = decode_commit(xdr, &res->commit_res);
1333 out:
1334 	return status;
1335 }
1336 
1337 /*
1338  * Decode OFFLOAD_CANCEL response
1339  */
1340 static int nfs4_xdr_dec_offload_cancel(struct rpc_rqst *rqstp,
1341 				       struct xdr_stream *xdr,
1342 				       void *data)
1343 {
1344 	struct nfs42_offload_status_res *res = data;
1345 	struct compound_hdr hdr;
1346 	int status;
1347 
1348 	status = decode_compound_hdr(xdr, &hdr);
1349 	if (status)
1350 		goto out;
1351 	status = decode_sequence(xdr, &res->osr_seq_res, rqstp);
1352 	if (status)
1353 		goto out;
1354 	status = decode_putfh(xdr);
1355 	if (status)
1356 		goto out;
1357 	status = decode_offload_cancel(xdr, res);
1358 
1359 out:
1360 	return status;
1361 }
1362 
1363 /*
1364  * Decode COPY_NOTIFY response
1365  */
1366 static int nfs4_xdr_dec_copy_notify(struct rpc_rqst *rqstp,
1367 				    struct xdr_stream *xdr,
1368 				    void *data)
1369 {
1370 	struct nfs42_copy_notify_res *res = data;
1371 	struct compound_hdr hdr;
1372 	int status;
1373 
1374 	status = decode_compound_hdr(xdr, &hdr);
1375 	if (status)
1376 		goto out;
1377 	status = decode_sequence(xdr, &res->cnr_seq_res, rqstp);
1378 	if (status)
1379 		goto out;
1380 	status = decode_putfh(xdr);
1381 	if (status)
1382 		goto out;
1383 	status = decode_copy_notify(xdr, res);
1384 
1385 out:
1386 	return status;
1387 }
1388 
1389 /*
1390  * Decode DEALLOCATE request
1391  */
1392 static int nfs4_xdr_dec_deallocate(struct rpc_rqst *rqstp,
1393 				   struct xdr_stream *xdr,
1394 				   void *data)
1395 {
1396 	struct nfs42_falloc_res *res = data;
1397 	struct compound_hdr hdr;
1398 	int status;
1399 
1400 	status = decode_compound_hdr(xdr, &hdr);
1401 	if (status)
1402 		goto out;
1403 	status = decode_sequence(xdr, &res->seq_res, rqstp);
1404 	if (status)
1405 		goto out;
1406 	status = decode_putfh(xdr);
1407 	if (status)
1408 		goto out;
1409 	status = decode_deallocate(xdr, res);
1410 	if (status)
1411 		goto out;
1412 	decode_getfattr(xdr, res->falloc_fattr, res->falloc_server);
1413 out:
1414 	return status;
1415 }
1416 
1417 /*
1418  * Decode READ_PLUS request
1419  */
1420 static int nfs4_xdr_dec_read_plus(struct rpc_rqst *rqstp,
1421 				  struct xdr_stream *xdr,
1422 				  void *data)
1423 {
1424 	struct nfs_pgio_res *res = data;
1425 	struct compound_hdr hdr;
1426 	int status;
1427 
1428 	xdr_set_scratch_buffer(xdr, res->scratch, sizeof(res->scratch));
1429 
1430 	status = decode_compound_hdr(xdr, &hdr);
1431 	if (status)
1432 		goto out;
1433 	status = decode_sequence(xdr, &res->seq_res, rqstp);
1434 	if (status)
1435 		goto out;
1436 	status = decode_putfh(xdr);
1437 	if (status)
1438 		goto out;
1439 	status = decode_read_plus(xdr, res);
1440 	if (!status)
1441 		status = res->count;
1442 out:
1443 	return status;
1444 }
1445 
1446 /*
1447  * Decode SEEK request
1448  */
1449 static int nfs4_xdr_dec_seek(struct rpc_rqst *rqstp,
1450 			     struct xdr_stream *xdr,
1451 			     void *data)
1452 {
1453 	struct nfs42_seek_res *res = data;
1454 	struct compound_hdr hdr;
1455 	int status;
1456 
1457 	status = decode_compound_hdr(xdr, &hdr);
1458 	if (status)
1459 		goto out;
1460 	status = decode_sequence(xdr, &res->seq_res, rqstp);
1461 	if (status)
1462 		goto out;
1463 	status = decode_putfh(xdr);
1464 	if (status)
1465 		goto out;
1466 	status = decode_seek(xdr, res);
1467 out:
1468 	return status;
1469 }
1470 
1471 /*
1472  * Decode LAYOUTSTATS request
1473  */
1474 static int nfs4_xdr_dec_layoutstats(struct rpc_rqst *rqstp,
1475 				    struct xdr_stream *xdr,
1476 				    void *data)
1477 {
1478 	struct nfs42_layoutstat_res *res = data;
1479 	struct compound_hdr hdr;
1480 	int status, i;
1481 
1482 	status = decode_compound_hdr(xdr, &hdr);
1483 	if (status)
1484 		goto out;
1485 	status = decode_sequence(xdr, &res->seq_res, rqstp);
1486 	if (status)
1487 		goto out;
1488 	status = decode_putfh(xdr);
1489 	if (status)
1490 		goto out;
1491 	WARN_ON(res->num_dev > PNFS_LAYOUTSTATS_MAXDEV);
1492 	for (i = 0; i < res->num_dev; i++) {
1493 		status = decode_layoutstats(xdr);
1494 		if (status)
1495 			goto out;
1496 	}
1497 out:
1498 	res->rpc_status = status;
1499 	return status;
1500 }
1501 
1502 /*
1503  * Decode CLONE request
1504  */
1505 static int nfs4_xdr_dec_clone(struct rpc_rqst *rqstp,
1506 			      struct xdr_stream *xdr,
1507 			      void *data)
1508 {
1509 	struct nfs42_clone_res *res = data;
1510 	struct compound_hdr hdr;
1511 	int status;
1512 
1513 	status = decode_compound_hdr(xdr, &hdr);
1514 	if (status)
1515 		goto out;
1516 	status = decode_sequence(xdr, &res->seq_res, rqstp);
1517 	if (status)
1518 		goto out;
1519 	status = decode_putfh(xdr);
1520 	if (status)
1521 		goto out;
1522 	status = decode_savefh(xdr);
1523 	if (status)
1524 		goto out;
1525 	status = decode_putfh(xdr);
1526 	if (status)
1527 		goto out;
1528 	status = decode_clone(xdr);
1529 	if (status)
1530 		goto out;
1531 	decode_getfattr(xdr, res->dst_fattr, res->server);
1532 out:
1533 	res->rpc_status = status;
1534 	return status;
1535 }
1536 
1537 /*
1538  * Decode LAYOUTERROR request
1539  */
1540 static int nfs4_xdr_dec_layouterror(struct rpc_rqst *rqstp,
1541 				    struct xdr_stream *xdr,
1542 				    void *data)
1543 {
1544 	struct nfs42_layouterror_res *res = data;
1545 	struct compound_hdr hdr;
1546 	int status, i;
1547 
1548 	status = decode_compound_hdr(xdr, &hdr);
1549 	if (status)
1550 		goto out;
1551 	status = decode_sequence(xdr, &res->seq_res, rqstp);
1552 	if (status)
1553 		goto out;
1554 	status = decode_putfh(xdr);
1555 
1556 	for (i = 0; i < res->num_errors && status == 0; i++)
1557 		status = decode_layouterror(xdr);
1558 out:
1559 	res->rpc_status = status;
1560 	return status;
1561 }
1562 
1563 /*
1564  * Decode SETXATTR request
1565  */
1566 static int nfs4_xdr_dec_setxattr(struct rpc_rqst *req, struct xdr_stream *xdr,
1567 				 void *data)
1568 {
1569 	struct nfs42_setxattrres *res = data;
1570 	struct compound_hdr hdr;
1571 	int status;
1572 
1573 	status = decode_compound_hdr(xdr, &hdr);
1574 	if (status)
1575 		goto out;
1576 	status = decode_sequence(xdr, &res->seq_res, req);
1577 	if (status)
1578 		goto out;
1579 	status = decode_putfh(xdr);
1580 	if (status)
1581 		goto out;
1582 
1583 	status = decode_setxattr(xdr, &res->cinfo);
1584 out:
1585 	return status;
1586 }
1587 
1588 /*
1589  * Decode GETXATTR request
1590  */
1591 static int nfs4_xdr_dec_getxattr(struct rpc_rqst *rqstp,
1592 				 struct xdr_stream *xdr, void *data)
1593 {
1594 	struct nfs42_getxattrres *res = data;
1595 	struct compound_hdr hdr;
1596 	int status;
1597 
1598 	status = decode_compound_hdr(xdr, &hdr);
1599 	if (status)
1600 		goto out;
1601 	status = decode_sequence(xdr, &res->seq_res, rqstp);
1602 	if (status)
1603 		goto out;
1604 	status = decode_putfh(xdr);
1605 	if (status)
1606 		goto out;
1607 	status = decode_getxattr(xdr, res, rqstp);
1608 out:
1609 	return status;
1610 }
1611 
1612 /*
1613  * Decode LISTXATTR request
1614  */
1615 static int nfs4_xdr_dec_listxattrs(struct rpc_rqst *rqstp,
1616 				   struct xdr_stream *xdr, void *data)
1617 {
1618 	struct nfs42_listxattrsres *res = data;
1619 	struct compound_hdr hdr;
1620 	int status;
1621 
1622 	xdr_set_scratch_page(xdr, res->scratch);
1623 
1624 	status = decode_compound_hdr(xdr, &hdr);
1625 	if (status)
1626 		goto out;
1627 	status = decode_sequence(xdr, &res->seq_res, rqstp);
1628 	if (status)
1629 		goto out;
1630 	status = decode_putfh(xdr);
1631 	if (status)
1632 		goto out;
1633 	status = decode_listxattrs(xdr, res);
1634 out:
1635 	return status;
1636 }
1637 
1638 /*
1639  * Decode REMOVEXATTR request
1640  */
1641 static int nfs4_xdr_dec_removexattr(struct rpc_rqst *req,
1642 				    struct xdr_stream *xdr, void *data)
1643 {
1644 	struct nfs42_removexattrres *res = data;
1645 	struct compound_hdr hdr;
1646 	int status;
1647 
1648 	status = decode_compound_hdr(xdr, &hdr);
1649 	if (status)
1650 		goto out;
1651 	status = decode_sequence(xdr, &res->seq_res, req);
1652 	if (status)
1653 		goto out;
1654 	status = decode_putfh(xdr);
1655 	if (status)
1656 		goto out;
1657 
1658 	status = decode_removexattr(xdr, &res->cinfo);
1659 out:
1660 	return status;
1661 }
1662 #endif /* __LINUX_FS_NFS_NFS4_2XDR_H */
1663