xref: /openbmc/linux/fs/nfs/nfs3proc.c (revision cd5d5810)
1 /*
2  *  linux/fs/nfs/nfs3proc.c
3  *
4  *  Client-side NFSv3 procedures stubs.
5  *
6  *  Copyright (C) 1997, Olaf Kirch
7  */
8 
9 #include <linux/mm.h>
10 #include <linux/errno.h>
11 #include <linux/string.h>
12 #include <linux/sunrpc/clnt.h>
13 #include <linux/slab.h>
14 #include <linux/nfs.h>
15 #include <linux/nfs3.h>
16 #include <linux/nfs_fs.h>
17 #include <linux/nfs_page.h>
18 #include <linux/lockd/bind.h>
19 #include <linux/nfs_mount.h>
20 #include <linux/freezer.h>
21 
22 #include "iostat.h"
23 #include "internal.h"
24 
25 #define NFSDBG_FACILITY		NFSDBG_PROC
26 
27 /* A wrapper to handle the EJUKEBOX error messages */
28 static int
29 nfs3_rpc_wrapper(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
30 {
31 	int res;
32 	do {
33 		res = rpc_call_sync(clnt, msg, flags);
34 		if (res != -EJUKEBOX)
35 			break;
36 		freezable_schedule_timeout_killable_unsafe(NFS_JUKEBOX_RETRY_TIME);
37 		res = -ERESTARTSYS;
38 	} while (!fatal_signal_pending(current));
39 	return res;
40 }
41 
42 #define rpc_call_sync(clnt, msg, flags)	nfs3_rpc_wrapper(clnt, msg, flags)
43 
44 static int
45 nfs3_async_handle_jukebox(struct rpc_task *task, struct inode *inode)
46 {
47 	if (task->tk_status != -EJUKEBOX)
48 		return 0;
49 	if (task->tk_status == -EJUKEBOX)
50 		nfs_inc_stats(inode, NFSIOS_DELAY);
51 	task->tk_status = 0;
52 	rpc_restart_call(task);
53 	rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
54 	return 1;
55 }
56 
57 static int
58 do_proc_get_root(struct rpc_clnt *client, struct nfs_fh *fhandle,
59 		 struct nfs_fsinfo *info)
60 {
61 	struct rpc_message msg = {
62 		.rpc_proc	= &nfs3_procedures[NFS3PROC_FSINFO],
63 		.rpc_argp	= fhandle,
64 		.rpc_resp	= info,
65 	};
66 	int	status;
67 
68 	dprintk("%s: call  fsinfo\n", __func__);
69 	nfs_fattr_init(info->fattr);
70 	status = rpc_call_sync(client, &msg, 0);
71 	dprintk("%s: reply fsinfo: %d\n", __func__, status);
72 	if (status == 0 && !(info->fattr->valid & NFS_ATTR_FATTR)) {
73 		msg.rpc_proc = &nfs3_procedures[NFS3PROC_GETATTR];
74 		msg.rpc_resp = info->fattr;
75 		status = rpc_call_sync(client, &msg, 0);
76 		dprintk("%s: reply getattr: %d\n", __func__, status);
77 	}
78 	return status;
79 }
80 
81 /*
82  * Bare-bones access to getattr: this is for nfs_get_root/nfs_get_sb
83  */
84 static int
85 nfs3_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
86 		   struct nfs_fsinfo *info)
87 {
88 	int	status;
89 
90 	status = do_proc_get_root(server->client, fhandle, info);
91 	if (status && server->nfs_client->cl_rpcclient != server->client)
92 		status = do_proc_get_root(server->nfs_client->cl_rpcclient, fhandle, info);
93 	return status;
94 }
95 
96 /*
97  * One function for each procedure in the NFS protocol.
98  */
99 static int
100 nfs3_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle,
101 		struct nfs_fattr *fattr, struct nfs4_label *label)
102 {
103 	struct rpc_message msg = {
104 		.rpc_proc	= &nfs3_procedures[NFS3PROC_GETATTR],
105 		.rpc_argp	= fhandle,
106 		.rpc_resp	= fattr,
107 	};
108 	int	status;
109 
110 	dprintk("NFS call  getattr\n");
111 	nfs_fattr_init(fattr);
112 	status = rpc_call_sync(server->client, &msg, 0);
113 	dprintk("NFS reply getattr: %d\n", status);
114 	return status;
115 }
116 
117 static int
118 nfs3_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
119 			struct iattr *sattr)
120 {
121 	struct inode *inode = dentry->d_inode;
122 	struct nfs3_sattrargs	arg = {
123 		.fh		= NFS_FH(inode),
124 		.sattr		= sattr,
125 	};
126 	struct rpc_message msg = {
127 		.rpc_proc	= &nfs3_procedures[NFS3PROC_SETATTR],
128 		.rpc_argp	= &arg,
129 		.rpc_resp	= fattr,
130 	};
131 	int	status;
132 
133 	dprintk("NFS call  setattr\n");
134 	if (sattr->ia_valid & ATTR_FILE)
135 		msg.rpc_cred = nfs_file_cred(sattr->ia_file);
136 	nfs_fattr_init(fattr);
137 	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
138 	if (status == 0)
139 		nfs_setattr_update_inode(inode, sattr);
140 	dprintk("NFS reply setattr: %d\n", status);
141 	return status;
142 }
143 
144 static int
145 nfs3_proc_lookup(struct inode *dir, struct qstr *name,
146 		 struct nfs_fh *fhandle, struct nfs_fattr *fattr,
147 		 struct nfs4_label *label)
148 {
149 	struct nfs3_diropargs	arg = {
150 		.fh		= NFS_FH(dir),
151 		.name		= name->name,
152 		.len		= name->len
153 	};
154 	struct nfs3_diropres	res = {
155 		.fh		= fhandle,
156 		.fattr		= fattr
157 	};
158 	struct rpc_message msg = {
159 		.rpc_proc	= &nfs3_procedures[NFS3PROC_LOOKUP],
160 		.rpc_argp	= &arg,
161 		.rpc_resp	= &res,
162 	};
163 	int			status;
164 
165 	dprintk("NFS call  lookup %s\n", name->name);
166 	res.dir_attr = nfs_alloc_fattr();
167 	if (res.dir_attr == NULL)
168 		return -ENOMEM;
169 
170 	nfs_fattr_init(fattr);
171 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
172 	nfs_refresh_inode(dir, res.dir_attr);
173 	if (status >= 0 && !(fattr->valid & NFS_ATTR_FATTR)) {
174 		msg.rpc_proc = &nfs3_procedures[NFS3PROC_GETATTR];
175 		msg.rpc_argp = fhandle;
176 		msg.rpc_resp = fattr;
177 		status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
178 	}
179 	nfs_free_fattr(res.dir_attr);
180 	dprintk("NFS reply lookup: %d\n", status);
181 	return status;
182 }
183 
184 static int nfs3_proc_access(struct inode *inode, struct nfs_access_entry *entry)
185 {
186 	struct nfs3_accessargs	arg = {
187 		.fh		= NFS_FH(inode),
188 	};
189 	struct nfs3_accessres	res;
190 	struct rpc_message msg = {
191 		.rpc_proc	= &nfs3_procedures[NFS3PROC_ACCESS],
192 		.rpc_argp	= &arg,
193 		.rpc_resp	= &res,
194 		.rpc_cred	= entry->cred,
195 	};
196 	int mode = entry->mask;
197 	int status = -ENOMEM;
198 
199 	dprintk("NFS call  access\n");
200 
201 	if (mode & MAY_READ)
202 		arg.access |= NFS3_ACCESS_READ;
203 	if (S_ISDIR(inode->i_mode)) {
204 		if (mode & MAY_WRITE)
205 			arg.access |= NFS3_ACCESS_MODIFY | NFS3_ACCESS_EXTEND | NFS3_ACCESS_DELETE;
206 		if (mode & MAY_EXEC)
207 			arg.access |= NFS3_ACCESS_LOOKUP;
208 	} else {
209 		if (mode & MAY_WRITE)
210 			arg.access |= NFS3_ACCESS_MODIFY | NFS3_ACCESS_EXTEND;
211 		if (mode & MAY_EXEC)
212 			arg.access |= NFS3_ACCESS_EXECUTE;
213 	}
214 
215 	res.fattr = nfs_alloc_fattr();
216 	if (res.fattr == NULL)
217 		goto out;
218 
219 	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
220 	nfs_refresh_inode(inode, res.fattr);
221 	if (status == 0) {
222 		entry->mask = 0;
223 		if (res.access & NFS3_ACCESS_READ)
224 			entry->mask |= MAY_READ;
225 		if (res.access & (NFS3_ACCESS_MODIFY | NFS3_ACCESS_EXTEND | NFS3_ACCESS_DELETE))
226 			entry->mask |= MAY_WRITE;
227 		if (res.access & (NFS3_ACCESS_LOOKUP|NFS3_ACCESS_EXECUTE))
228 			entry->mask |= MAY_EXEC;
229 	}
230 	nfs_free_fattr(res.fattr);
231 out:
232 	dprintk("NFS reply access: %d\n", status);
233 	return status;
234 }
235 
236 static int nfs3_proc_readlink(struct inode *inode, struct page *page,
237 		unsigned int pgbase, unsigned int pglen)
238 {
239 	struct nfs_fattr	*fattr;
240 	struct nfs3_readlinkargs args = {
241 		.fh		= NFS_FH(inode),
242 		.pgbase		= pgbase,
243 		.pglen		= pglen,
244 		.pages		= &page
245 	};
246 	struct rpc_message msg = {
247 		.rpc_proc	= &nfs3_procedures[NFS3PROC_READLINK],
248 		.rpc_argp	= &args,
249 	};
250 	int status = -ENOMEM;
251 
252 	dprintk("NFS call  readlink\n");
253 	fattr = nfs_alloc_fattr();
254 	if (fattr == NULL)
255 		goto out;
256 	msg.rpc_resp = fattr;
257 
258 	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
259 	nfs_refresh_inode(inode, fattr);
260 	nfs_free_fattr(fattr);
261 out:
262 	dprintk("NFS reply readlink: %d\n", status);
263 	return status;
264 }
265 
266 struct nfs3_createdata {
267 	struct rpc_message msg;
268 	union {
269 		struct nfs3_createargs create;
270 		struct nfs3_mkdirargs mkdir;
271 		struct nfs3_symlinkargs symlink;
272 		struct nfs3_mknodargs mknod;
273 	} arg;
274 	struct nfs3_diropres res;
275 	struct nfs_fh fh;
276 	struct nfs_fattr fattr;
277 	struct nfs_fattr dir_attr;
278 };
279 
280 static struct nfs3_createdata *nfs3_alloc_createdata(void)
281 {
282 	struct nfs3_createdata *data;
283 
284 	data = kzalloc(sizeof(*data), GFP_KERNEL);
285 	if (data != NULL) {
286 		data->msg.rpc_argp = &data->arg;
287 		data->msg.rpc_resp = &data->res;
288 		data->res.fh = &data->fh;
289 		data->res.fattr = &data->fattr;
290 		data->res.dir_attr = &data->dir_attr;
291 		nfs_fattr_init(data->res.fattr);
292 		nfs_fattr_init(data->res.dir_attr);
293 	}
294 	return data;
295 }
296 
297 static int nfs3_do_create(struct inode *dir, struct dentry *dentry, struct nfs3_createdata *data)
298 {
299 	int status;
300 
301 	status = rpc_call_sync(NFS_CLIENT(dir), &data->msg, 0);
302 	nfs_post_op_update_inode(dir, data->res.dir_attr);
303 	if (status == 0)
304 		status = nfs_instantiate(dentry, data->res.fh, data->res.fattr, NULL);
305 	return status;
306 }
307 
308 static void nfs3_free_createdata(struct nfs3_createdata *data)
309 {
310 	kfree(data);
311 }
312 
313 /*
314  * Create a regular file.
315  */
316 static int
317 nfs3_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
318 		 int flags)
319 {
320 	struct nfs3_createdata *data;
321 	umode_t mode = sattr->ia_mode;
322 	int status = -ENOMEM;
323 
324 	dprintk("NFS call  create %s\n", dentry->d_name.name);
325 
326 	data = nfs3_alloc_createdata();
327 	if (data == NULL)
328 		goto out;
329 
330 	data->msg.rpc_proc = &nfs3_procedures[NFS3PROC_CREATE];
331 	data->arg.create.fh = NFS_FH(dir);
332 	data->arg.create.name = dentry->d_name.name;
333 	data->arg.create.len = dentry->d_name.len;
334 	data->arg.create.sattr = sattr;
335 
336 	data->arg.create.createmode = NFS3_CREATE_UNCHECKED;
337 	if (flags & O_EXCL) {
338 		data->arg.create.createmode  = NFS3_CREATE_EXCLUSIVE;
339 		data->arg.create.verifier[0] = cpu_to_be32(jiffies);
340 		data->arg.create.verifier[1] = cpu_to_be32(current->pid);
341 	}
342 
343 	sattr->ia_mode &= ~current_umask();
344 
345 	for (;;) {
346 		status = nfs3_do_create(dir, dentry, data);
347 
348 		if (status != -ENOTSUPP)
349 			break;
350 		/* If the server doesn't support the exclusive creation
351 		 * semantics, try again with simple 'guarded' mode. */
352 		switch (data->arg.create.createmode) {
353 			case NFS3_CREATE_EXCLUSIVE:
354 				data->arg.create.createmode = NFS3_CREATE_GUARDED;
355 				break;
356 
357 			case NFS3_CREATE_GUARDED:
358 				data->arg.create.createmode = NFS3_CREATE_UNCHECKED;
359 				break;
360 
361 			case NFS3_CREATE_UNCHECKED:
362 				goto out;
363 		}
364 		nfs_fattr_init(data->res.dir_attr);
365 		nfs_fattr_init(data->res.fattr);
366 	}
367 
368 	if (status != 0)
369 		goto out;
370 
371 	/* When we created the file with exclusive semantics, make
372 	 * sure we set the attributes afterwards. */
373 	if (data->arg.create.createmode == NFS3_CREATE_EXCLUSIVE) {
374 		dprintk("NFS call  setattr (post-create)\n");
375 
376 		if (!(sattr->ia_valid & ATTR_ATIME_SET))
377 			sattr->ia_valid |= ATTR_ATIME;
378 		if (!(sattr->ia_valid & ATTR_MTIME_SET))
379 			sattr->ia_valid |= ATTR_MTIME;
380 
381 		/* Note: we could use a guarded setattr here, but I'm
382 		 * not sure this buys us anything (and I'd have
383 		 * to revamp the NFSv3 XDR code) */
384 		status = nfs3_proc_setattr(dentry, data->res.fattr, sattr);
385 		nfs_post_op_update_inode(dentry->d_inode, data->res.fattr);
386 		dprintk("NFS reply setattr (post-create): %d\n", status);
387 		if (status != 0)
388 			goto out;
389 	}
390 	status = nfs3_proc_set_default_acl(dir, dentry->d_inode, mode);
391 out:
392 	nfs3_free_createdata(data);
393 	dprintk("NFS reply create: %d\n", status);
394 	return status;
395 }
396 
397 static int
398 nfs3_proc_remove(struct inode *dir, struct qstr *name)
399 {
400 	struct nfs_removeargs arg = {
401 		.fh = NFS_FH(dir),
402 		.name = *name,
403 	};
404 	struct nfs_removeres res;
405 	struct rpc_message msg = {
406 		.rpc_proc = &nfs3_procedures[NFS3PROC_REMOVE],
407 		.rpc_argp = &arg,
408 		.rpc_resp = &res,
409 	};
410 	int status = -ENOMEM;
411 
412 	dprintk("NFS call  remove %s\n", name->name);
413 	res.dir_attr = nfs_alloc_fattr();
414 	if (res.dir_attr == NULL)
415 		goto out;
416 
417 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
418 	nfs_post_op_update_inode(dir, res.dir_attr);
419 	nfs_free_fattr(res.dir_attr);
420 out:
421 	dprintk("NFS reply remove: %d\n", status);
422 	return status;
423 }
424 
425 static void
426 nfs3_proc_unlink_setup(struct rpc_message *msg, struct inode *dir)
427 {
428 	msg->rpc_proc = &nfs3_procedures[NFS3PROC_REMOVE];
429 }
430 
431 static void nfs3_proc_unlink_rpc_prepare(struct rpc_task *task, struct nfs_unlinkdata *data)
432 {
433 	rpc_call_start(task);
434 }
435 
436 static int
437 nfs3_proc_unlink_done(struct rpc_task *task, struct inode *dir)
438 {
439 	struct nfs_removeres *res;
440 	if (nfs3_async_handle_jukebox(task, dir))
441 		return 0;
442 	res = task->tk_msg.rpc_resp;
443 	nfs_post_op_update_inode(dir, res->dir_attr);
444 	return 1;
445 }
446 
447 static void
448 nfs3_proc_rename_setup(struct rpc_message *msg, struct inode *dir)
449 {
450 	msg->rpc_proc = &nfs3_procedures[NFS3PROC_RENAME];
451 }
452 
453 static void nfs3_proc_rename_rpc_prepare(struct rpc_task *task, struct nfs_renamedata *data)
454 {
455 	rpc_call_start(task);
456 }
457 
458 static int
459 nfs3_proc_rename_done(struct rpc_task *task, struct inode *old_dir,
460 		      struct inode *new_dir)
461 {
462 	struct nfs_renameres *res;
463 
464 	if (nfs3_async_handle_jukebox(task, old_dir))
465 		return 0;
466 	res = task->tk_msg.rpc_resp;
467 
468 	nfs_post_op_update_inode(old_dir, res->old_fattr);
469 	nfs_post_op_update_inode(new_dir, res->new_fattr);
470 	return 1;
471 }
472 
473 static int
474 nfs3_proc_rename(struct inode *old_dir, struct qstr *old_name,
475 		 struct inode *new_dir, struct qstr *new_name)
476 {
477 	struct nfs_renameargs	arg = {
478 		.old_dir	= NFS_FH(old_dir),
479 		.old_name	= old_name,
480 		.new_dir	= NFS_FH(new_dir),
481 		.new_name	= new_name,
482 	};
483 	struct nfs_renameres res;
484 	struct rpc_message msg = {
485 		.rpc_proc	= &nfs3_procedures[NFS3PROC_RENAME],
486 		.rpc_argp	= &arg,
487 		.rpc_resp	= &res,
488 	};
489 	int status = -ENOMEM;
490 
491 	dprintk("NFS call  rename %s -> %s\n", old_name->name, new_name->name);
492 
493 	res.old_fattr = nfs_alloc_fattr();
494 	res.new_fattr = nfs_alloc_fattr();
495 	if (res.old_fattr == NULL || res.new_fattr == NULL)
496 		goto out;
497 
498 	status = rpc_call_sync(NFS_CLIENT(old_dir), &msg, 0);
499 	nfs_post_op_update_inode(old_dir, res.old_fattr);
500 	nfs_post_op_update_inode(new_dir, res.new_fattr);
501 out:
502 	nfs_free_fattr(res.old_fattr);
503 	nfs_free_fattr(res.new_fattr);
504 	dprintk("NFS reply rename: %d\n", status);
505 	return status;
506 }
507 
508 static int
509 nfs3_proc_link(struct inode *inode, struct inode *dir, struct qstr *name)
510 {
511 	struct nfs3_linkargs	arg = {
512 		.fromfh		= NFS_FH(inode),
513 		.tofh		= NFS_FH(dir),
514 		.toname		= name->name,
515 		.tolen		= name->len
516 	};
517 	struct nfs3_linkres	res;
518 	struct rpc_message msg = {
519 		.rpc_proc	= &nfs3_procedures[NFS3PROC_LINK],
520 		.rpc_argp	= &arg,
521 		.rpc_resp	= &res,
522 	};
523 	int status = -ENOMEM;
524 
525 	dprintk("NFS call  link %s\n", name->name);
526 	res.fattr = nfs_alloc_fattr();
527 	res.dir_attr = nfs_alloc_fattr();
528 	if (res.fattr == NULL || res.dir_attr == NULL)
529 		goto out;
530 
531 	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
532 	nfs_post_op_update_inode(dir, res.dir_attr);
533 	nfs_post_op_update_inode(inode, res.fattr);
534 out:
535 	nfs_free_fattr(res.dir_attr);
536 	nfs_free_fattr(res.fattr);
537 	dprintk("NFS reply link: %d\n", status);
538 	return status;
539 }
540 
541 static int
542 nfs3_proc_symlink(struct inode *dir, struct dentry *dentry, struct page *page,
543 		  unsigned int len, struct iattr *sattr)
544 {
545 	struct nfs3_createdata *data;
546 	int status = -ENOMEM;
547 
548 	if (len > NFS3_MAXPATHLEN)
549 		return -ENAMETOOLONG;
550 
551 	dprintk("NFS call  symlink %s\n", dentry->d_name.name);
552 
553 	data = nfs3_alloc_createdata();
554 	if (data == NULL)
555 		goto out;
556 	data->msg.rpc_proc = &nfs3_procedures[NFS3PROC_SYMLINK];
557 	data->arg.symlink.fromfh = NFS_FH(dir);
558 	data->arg.symlink.fromname = dentry->d_name.name;
559 	data->arg.symlink.fromlen = dentry->d_name.len;
560 	data->arg.symlink.pages = &page;
561 	data->arg.symlink.pathlen = len;
562 	data->arg.symlink.sattr = sattr;
563 
564 	status = nfs3_do_create(dir, dentry, data);
565 
566 	nfs3_free_createdata(data);
567 out:
568 	dprintk("NFS reply symlink: %d\n", status);
569 	return status;
570 }
571 
572 static int
573 nfs3_proc_mkdir(struct inode *dir, struct dentry *dentry, struct iattr *sattr)
574 {
575 	struct nfs3_createdata *data;
576 	umode_t mode = sattr->ia_mode;
577 	int status = -ENOMEM;
578 
579 	dprintk("NFS call  mkdir %s\n", dentry->d_name.name);
580 
581 	sattr->ia_mode &= ~current_umask();
582 
583 	data = nfs3_alloc_createdata();
584 	if (data == NULL)
585 		goto out;
586 
587 	data->msg.rpc_proc = &nfs3_procedures[NFS3PROC_MKDIR];
588 	data->arg.mkdir.fh = NFS_FH(dir);
589 	data->arg.mkdir.name = dentry->d_name.name;
590 	data->arg.mkdir.len = dentry->d_name.len;
591 	data->arg.mkdir.sattr = sattr;
592 
593 	status = nfs3_do_create(dir, dentry, data);
594 	if (status != 0)
595 		goto out;
596 
597 	status = nfs3_proc_set_default_acl(dir, dentry->d_inode, mode);
598 out:
599 	nfs3_free_createdata(data);
600 	dprintk("NFS reply mkdir: %d\n", status);
601 	return status;
602 }
603 
604 static int
605 nfs3_proc_rmdir(struct inode *dir, struct qstr *name)
606 {
607 	struct nfs_fattr	*dir_attr;
608 	struct nfs3_diropargs	arg = {
609 		.fh		= NFS_FH(dir),
610 		.name		= name->name,
611 		.len		= name->len
612 	};
613 	struct rpc_message msg = {
614 		.rpc_proc	= &nfs3_procedures[NFS3PROC_RMDIR],
615 		.rpc_argp	= &arg,
616 	};
617 	int status = -ENOMEM;
618 
619 	dprintk("NFS call  rmdir %s\n", name->name);
620 	dir_attr = nfs_alloc_fattr();
621 	if (dir_attr == NULL)
622 		goto out;
623 
624 	msg.rpc_resp = dir_attr;
625 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
626 	nfs_post_op_update_inode(dir, dir_attr);
627 	nfs_free_fattr(dir_attr);
628 out:
629 	dprintk("NFS reply rmdir: %d\n", status);
630 	return status;
631 }
632 
633 /*
634  * The READDIR implementation is somewhat hackish - we pass the user buffer
635  * to the encode function, which installs it in the receive iovec.
636  * The decode function itself doesn't perform any decoding, it just makes
637  * sure the reply is syntactically correct.
638  *
639  * Also note that this implementation handles both plain readdir and
640  * readdirplus.
641  */
642 static int
643 nfs3_proc_readdir(struct dentry *dentry, struct rpc_cred *cred,
644 		  u64 cookie, struct page **pages, unsigned int count, int plus)
645 {
646 	struct inode		*dir = dentry->d_inode;
647 	__be32			*verf = NFS_I(dir)->cookieverf;
648 	struct nfs3_readdirargs	arg = {
649 		.fh		= NFS_FH(dir),
650 		.cookie		= cookie,
651 		.verf		= {verf[0], verf[1]},
652 		.plus		= plus,
653 		.count		= count,
654 		.pages		= pages
655 	};
656 	struct nfs3_readdirres	res = {
657 		.verf		= verf,
658 		.plus		= plus
659 	};
660 	struct rpc_message	msg = {
661 		.rpc_proc	= &nfs3_procedures[NFS3PROC_READDIR],
662 		.rpc_argp	= &arg,
663 		.rpc_resp	= &res,
664 		.rpc_cred	= cred
665 	};
666 	int status = -ENOMEM;
667 
668 	if (plus)
669 		msg.rpc_proc = &nfs3_procedures[NFS3PROC_READDIRPLUS];
670 
671 	dprintk("NFS call  readdir%s %d\n",
672 			plus? "plus" : "", (unsigned int) cookie);
673 
674 	res.dir_attr = nfs_alloc_fattr();
675 	if (res.dir_attr == NULL)
676 		goto out;
677 
678 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
679 
680 	nfs_invalidate_atime(dir);
681 	nfs_refresh_inode(dir, res.dir_attr);
682 
683 	nfs_free_fattr(res.dir_attr);
684 out:
685 	dprintk("NFS reply readdir%s: %d\n",
686 			plus? "plus" : "", status);
687 	return status;
688 }
689 
690 static int
691 nfs3_proc_mknod(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
692 		dev_t rdev)
693 {
694 	struct nfs3_createdata *data;
695 	umode_t mode = sattr->ia_mode;
696 	int status = -ENOMEM;
697 
698 	dprintk("NFS call  mknod %s %u:%u\n", dentry->d_name.name,
699 			MAJOR(rdev), MINOR(rdev));
700 
701 	sattr->ia_mode &= ~current_umask();
702 
703 	data = nfs3_alloc_createdata();
704 	if (data == NULL)
705 		goto out;
706 
707 	data->msg.rpc_proc = &nfs3_procedures[NFS3PROC_MKNOD];
708 	data->arg.mknod.fh = NFS_FH(dir);
709 	data->arg.mknod.name = dentry->d_name.name;
710 	data->arg.mknod.len = dentry->d_name.len;
711 	data->arg.mknod.sattr = sattr;
712 	data->arg.mknod.rdev = rdev;
713 
714 	switch (sattr->ia_mode & S_IFMT) {
715 	case S_IFBLK:
716 		data->arg.mknod.type = NF3BLK;
717 		break;
718 	case S_IFCHR:
719 		data->arg.mknod.type = NF3CHR;
720 		break;
721 	case S_IFIFO:
722 		data->arg.mknod.type = NF3FIFO;
723 		break;
724 	case S_IFSOCK:
725 		data->arg.mknod.type = NF3SOCK;
726 		break;
727 	default:
728 		status = -EINVAL;
729 		goto out;
730 	}
731 
732 	status = nfs3_do_create(dir, dentry, data);
733 	if (status != 0)
734 		goto out;
735 	status = nfs3_proc_set_default_acl(dir, dentry->d_inode, mode);
736 out:
737 	nfs3_free_createdata(data);
738 	dprintk("NFS reply mknod: %d\n", status);
739 	return status;
740 }
741 
742 static int
743 nfs3_proc_statfs(struct nfs_server *server, struct nfs_fh *fhandle,
744 		 struct nfs_fsstat *stat)
745 {
746 	struct rpc_message msg = {
747 		.rpc_proc	= &nfs3_procedures[NFS3PROC_FSSTAT],
748 		.rpc_argp	= fhandle,
749 		.rpc_resp	= stat,
750 	};
751 	int	status;
752 
753 	dprintk("NFS call  fsstat\n");
754 	nfs_fattr_init(stat->fattr);
755 	status = rpc_call_sync(server->client, &msg, 0);
756 	dprintk("NFS reply fsstat: %d\n", status);
757 	return status;
758 }
759 
760 static int
761 do_proc_fsinfo(struct rpc_clnt *client, struct nfs_fh *fhandle,
762 		 struct nfs_fsinfo *info)
763 {
764 	struct rpc_message msg = {
765 		.rpc_proc	= &nfs3_procedures[NFS3PROC_FSINFO],
766 		.rpc_argp	= fhandle,
767 		.rpc_resp	= info,
768 	};
769 	int	status;
770 
771 	dprintk("NFS call  fsinfo\n");
772 	nfs_fattr_init(info->fattr);
773 	status = rpc_call_sync(client, &msg, 0);
774 	dprintk("NFS reply fsinfo: %d\n", status);
775 	return status;
776 }
777 
778 /*
779  * Bare-bones access to fsinfo: this is for nfs_get_root/nfs_get_sb via
780  * nfs_create_server
781  */
782 static int
783 nfs3_proc_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle,
784 		   struct nfs_fsinfo *info)
785 {
786 	int	status;
787 
788 	status = do_proc_fsinfo(server->client, fhandle, info);
789 	if (status && server->nfs_client->cl_rpcclient != server->client)
790 		status = do_proc_fsinfo(server->nfs_client->cl_rpcclient, fhandle, info);
791 	return status;
792 }
793 
794 static int
795 nfs3_proc_pathconf(struct nfs_server *server, struct nfs_fh *fhandle,
796 		   struct nfs_pathconf *info)
797 {
798 	struct rpc_message msg = {
799 		.rpc_proc	= &nfs3_procedures[NFS3PROC_PATHCONF],
800 		.rpc_argp	= fhandle,
801 		.rpc_resp	= info,
802 	};
803 	int	status;
804 
805 	dprintk("NFS call  pathconf\n");
806 	nfs_fattr_init(info->fattr);
807 	status = rpc_call_sync(server->client, &msg, 0);
808 	dprintk("NFS reply pathconf: %d\n", status);
809 	return status;
810 }
811 
812 static int nfs3_read_done(struct rpc_task *task, struct nfs_read_data *data)
813 {
814 	struct inode *inode = data->header->inode;
815 
816 	if (nfs3_async_handle_jukebox(task, inode))
817 		return -EAGAIN;
818 
819 	nfs_invalidate_atime(inode);
820 	nfs_refresh_inode(inode, &data->fattr);
821 	return 0;
822 }
823 
824 static void nfs3_proc_read_setup(struct nfs_read_data *data, struct rpc_message *msg)
825 {
826 	msg->rpc_proc = &nfs3_procedures[NFS3PROC_READ];
827 }
828 
829 static int nfs3_proc_read_rpc_prepare(struct rpc_task *task, struct nfs_read_data *data)
830 {
831 	rpc_call_start(task);
832 	return 0;
833 }
834 
835 static int nfs3_write_done(struct rpc_task *task, struct nfs_write_data *data)
836 {
837 	struct inode *inode = data->header->inode;
838 
839 	if (nfs3_async_handle_jukebox(task, inode))
840 		return -EAGAIN;
841 	if (task->tk_status >= 0)
842 		nfs_post_op_update_inode_force_wcc(inode, data->res.fattr);
843 	return 0;
844 }
845 
846 static void nfs3_proc_write_setup(struct nfs_write_data *data, struct rpc_message *msg)
847 {
848 	msg->rpc_proc = &nfs3_procedures[NFS3PROC_WRITE];
849 }
850 
851 static int nfs3_proc_write_rpc_prepare(struct rpc_task *task, struct nfs_write_data *data)
852 {
853 	rpc_call_start(task);
854 	return 0;
855 }
856 
857 static void nfs3_proc_commit_rpc_prepare(struct rpc_task *task, struct nfs_commit_data *data)
858 {
859 	rpc_call_start(task);
860 }
861 
862 static int nfs3_commit_done(struct rpc_task *task, struct nfs_commit_data *data)
863 {
864 	if (nfs3_async_handle_jukebox(task, data->inode))
865 		return -EAGAIN;
866 	nfs_refresh_inode(data->inode, data->res.fattr);
867 	return 0;
868 }
869 
870 static void nfs3_proc_commit_setup(struct nfs_commit_data *data, struct rpc_message *msg)
871 {
872 	msg->rpc_proc = &nfs3_procedures[NFS3PROC_COMMIT];
873 }
874 
875 static int
876 nfs3_proc_lock(struct file *filp, int cmd, struct file_lock *fl)
877 {
878 	struct inode *inode = file_inode(filp);
879 
880 	return nlmclnt_proc(NFS_SERVER(inode)->nlm_host, cmd, fl);
881 }
882 
883 static int nfs3_have_delegation(struct inode *inode, fmode_t flags)
884 {
885 	return 0;
886 }
887 
888 static int nfs3_return_delegation(struct inode *inode)
889 {
890 	nfs_wb_all(inode);
891 	return 0;
892 }
893 
894 static const struct inode_operations nfs3_dir_inode_operations = {
895 	.create		= nfs_create,
896 	.lookup		= nfs_lookup,
897 	.link		= nfs_link,
898 	.unlink		= nfs_unlink,
899 	.symlink	= nfs_symlink,
900 	.mkdir		= nfs_mkdir,
901 	.rmdir		= nfs_rmdir,
902 	.mknod		= nfs_mknod,
903 	.rename		= nfs_rename,
904 	.permission	= nfs_permission,
905 	.getattr	= nfs_getattr,
906 	.setattr	= nfs_setattr,
907 	.listxattr	= nfs3_listxattr,
908 	.getxattr	= nfs3_getxattr,
909 	.setxattr	= nfs3_setxattr,
910 	.removexattr	= nfs3_removexattr,
911 };
912 
913 static const struct inode_operations nfs3_file_inode_operations = {
914 	.permission	= nfs_permission,
915 	.getattr	= nfs_getattr,
916 	.setattr	= nfs_setattr,
917 	.listxattr	= nfs3_listxattr,
918 	.getxattr	= nfs3_getxattr,
919 	.setxattr	= nfs3_setxattr,
920 	.removexattr	= nfs3_removexattr,
921 };
922 
923 const struct nfs_rpc_ops nfs_v3_clientops = {
924 	.version	= 3,			/* protocol version */
925 	.dentry_ops	= &nfs_dentry_operations,
926 	.dir_inode_ops	= &nfs3_dir_inode_operations,
927 	.file_inode_ops	= &nfs3_file_inode_operations,
928 	.file_ops	= &nfs_file_operations,
929 	.getroot	= nfs3_proc_get_root,
930 	.submount	= nfs_submount,
931 	.try_mount	= nfs_try_mount,
932 	.getattr	= nfs3_proc_getattr,
933 	.setattr	= nfs3_proc_setattr,
934 	.lookup		= nfs3_proc_lookup,
935 	.access		= nfs3_proc_access,
936 	.readlink	= nfs3_proc_readlink,
937 	.create		= nfs3_proc_create,
938 	.remove		= nfs3_proc_remove,
939 	.unlink_setup	= nfs3_proc_unlink_setup,
940 	.unlink_rpc_prepare = nfs3_proc_unlink_rpc_prepare,
941 	.unlink_done	= nfs3_proc_unlink_done,
942 	.rename		= nfs3_proc_rename,
943 	.rename_setup	= nfs3_proc_rename_setup,
944 	.rename_rpc_prepare = nfs3_proc_rename_rpc_prepare,
945 	.rename_done	= nfs3_proc_rename_done,
946 	.link		= nfs3_proc_link,
947 	.symlink	= nfs3_proc_symlink,
948 	.mkdir		= nfs3_proc_mkdir,
949 	.rmdir		= nfs3_proc_rmdir,
950 	.readdir	= nfs3_proc_readdir,
951 	.mknod		= nfs3_proc_mknod,
952 	.statfs		= nfs3_proc_statfs,
953 	.fsinfo		= nfs3_proc_fsinfo,
954 	.pathconf	= nfs3_proc_pathconf,
955 	.decode_dirent	= nfs3_decode_dirent,
956 	.read_setup	= nfs3_proc_read_setup,
957 	.read_pageio_init = nfs_pageio_init_read,
958 	.read_rpc_prepare = nfs3_proc_read_rpc_prepare,
959 	.read_done	= nfs3_read_done,
960 	.write_setup	= nfs3_proc_write_setup,
961 	.write_pageio_init = nfs_pageio_init_write,
962 	.write_rpc_prepare = nfs3_proc_write_rpc_prepare,
963 	.write_done	= nfs3_write_done,
964 	.commit_setup	= nfs3_proc_commit_setup,
965 	.commit_rpc_prepare = nfs3_proc_commit_rpc_prepare,
966 	.commit_done	= nfs3_commit_done,
967 	.lock		= nfs3_proc_lock,
968 	.clear_acl_cache = nfs3_forget_cached_acls,
969 	.close_context	= nfs_close_context,
970 	.have_delegation = nfs3_have_delegation,
971 	.return_delegation = nfs3_return_delegation,
972 	.alloc_client	= nfs_alloc_client,
973 	.init_client	= nfs_init_client,
974 	.free_client	= nfs_free_client,
975 	.create_server	= nfs3_create_server,
976 	.clone_server	= nfs3_clone_server,
977 };
978