xref: /linux/fs/nfs/proc.c (revision 5ea5880764cbb164afb17a62e76ca75dc371409d)
1 // SPDX-License-Identifier: GPL-2.0
2 /*
3  *  linux/fs/nfs/proc.c
4  *
5  *  Copyright (C) 1992, 1993, 1994  Rick Sladkey
6  *
7  *  OS-independent nfs remote procedure call functions
8  *
9  *  Tuned by Alan Cox <A.Cox@swansea.ac.uk> for >3K buffers
10  *  so at last we can have decent(ish) throughput off a
11  *  Sun server.
12  *
13  *  Coding optimized and cleaned up by Florian La Roche.
14  *  Note: Error returns are optimized for NFS_OK, which isn't translated via
15  *  nfs_stat_to_errno(), but happens to be already the right return code.
16  *
17  *  Also, the code currently doesn't check the size of the packet, when
18  *  it decodes the packet.
19  *
20  *  Feel free to fix it and mail me the diffs if it worries you.
21  *
22  *  Completely rewritten to support the new RPC call interface;
23  *  rewrote and moved the entire XDR stuff to xdr.c
24  *  --Olaf Kirch June 1996
25  *
26  *  The code below initializes all auto variables explicitly, otherwise
27  *  it will fail to work as a module (gcc generates a memset call for an
28  *  incomplete struct).
29  */
30 
31 #include <linux/types.h>
32 #include <linux/param.h>
33 #include <linux/time.h>
34 #include <linux/mm.h>
35 #include <linux/errno.h>
36 #include <linux/string.h>
37 #include <linux/in.h>
38 #include <linux/pagemap.h>
39 #include <linux/sunrpc/clnt.h>
40 #include <linux/nfs.h>
41 #include <linux/nfs2.h>
42 #include <linux/nfs_fs.h>
43 #include <linux/nfs_page.h>
44 #include <linux/filelock.h>
45 #include <linux/lockd/bind.h>
46 #include <linux/freezer.h>
47 #include "internal.h"
48 
49 #define NFSDBG_FACILITY		NFSDBG_PROC
50 
51 /*
52  * Bare-bones access to getattr: this is for nfs_read_super.
53  */
54 static int
55 nfs_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
56 		  struct nfs_fsinfo *info)
57 {
58 	struct nfs_fattr *fattr = info->fattr;
59 	struct nfs2_fsstat fsinfo;
60 	struct rpc_message msg = {
61 		.rpc_proc	= &nfs_procedures[NFSPROC_GETATTR],
62 		.rpc_argp	= fhandle,
63 		.rpc_resp	= fattr,
64 	};
65 	int status;
66 
67 	dprintk("%s: call getattr\n", __func__);
68 	nfs_fattr_init(fattr);
69 	status = rpc_call_sync(server->client, &msg, 0);
70 	/* Retry with default authentication if different */
71 	if (status && server->nfs_client->cl_rpcclient != server->client)
72 		status = rpc_call_sync(server->nfs_client->cl_rpcclient, &msg, 0);
73 	dprintk("%s: reply getattr: %d\n", __func__, status);
74 	if (status)
75 		return status;
76 	dprintk("%s: call statfs\n", __func__);
77 	msg.rpc_proc = &nfs_procedures[NFSPROC_STATFS];
78 	msg.rpc_resp = &fsinfo;
79 	status = rpc_call_sync(server->client, &msg, 0);
80 	/* Retry with default authentication if different */
81 	if (status && server->nfs_client->cl_rpcclient != server->client)
82 		status = rpc_call_sync(server->nfs_client->cl_rpcclient, &msg, 0);
83 	dprintk("%s: reply statfs: %d\n", __func__, status);
84 	if (status)
85 		return status;
86 	info->rtmax  = NFS_MAXDATA;
87 	info->rtpref = fsinfo.tsize;
88 	info->rtmult = fsinfo.bsize;
89 	info->wtmax  = NFS_MAXDATA;
90 	info->wtpref = fsinfo.tsize;
91 	info->wtmult = fsinfo.bsize;
92 	info->dtpref = fsinfo.tsize;
93 	info->maxfilesize = 0x7FFFFFFF;
94 	info->lease_time = 0;
95 	info->change_attr_type = NFS4_CHANGE_TYPE_IS_UNDEFINED;
96 	info->xattr_support = 0;
97 	return 0;
98 }
99 
100 /*
101  * One function for each procedure in the NFS protocol.
102  */
103 static int
104 nfs_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle,
105 		struct nfs_fattr *fattr, struct inode *inode)
106 {
107 	struct rpc_message msg = {
108 		.rpc_proc	= &nfs_procedures[NFSPROC_GETATTR],
109 		.rpc_argp	= fhandle,
110 		.rpc_resp	= fattr,
111 	};
112 	int	status;
113 	unsigned short task_flags = 0;
114 
115 	/* Is this is an attribute revalidation, subject to softreval? */
116 	if (inode && (server->flags & NFS_MOUNT_SOFTREVAL))
117 		task_flags |= RPC_TASK_TIMEOUT;
118 
119 	dprintk("NFS call  getattr\n");
120 	nfs_fattr_init(fattr);
121 	status = rpc_call_sync(server->client, &msg, task_flags);
122 	dprintk("NFS reply getattr: %d\n", status);
123 	return status;
124 }
125 
126 static int
127 nfs_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
128 		 struct iattr *sattr)
129 {
130 	struct inode *inode = d_inode(dentry);
131 	struct nfs_sattrargs	arg = {
132 		.fh	= NFS_FH(inode),
133 		.sattr	= sattr
134 	};
135 	struct rpc_message msg = {
136 		.rpc_proc	= &nfs_procedures[NFSPROC_SETATTR],
137 		.rpc_argp	= &arg,
138 		.rpc_resp	= fattr,
139 	};
140 	int	status;
141 
142 	/* Mask out the non-modebit related stuff from attr->ia_mode */
143 	sattr->ia_mode &= S_IALLUGO;
144 
145 	dprintk("NFS call  setattr\n");
146 	if (sattr->ia_valid & ATTR_FILE)
147 		msg.rpc_cred = nfs_file_cred(sattr->ia_file);
148 	nfs_fattr_init(fattr);
149 	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
150 	if (status == 0)
151 		nfs_setattr_update_inode(inode, sattr, fattr);
152 	dprintk("NFS reply setattr: %d\n", status);
153 	return status;
154 }
155 
156 static int
157 nfs_proc_lookup(struct inode *dir, struct dentry *dentry, const struct qstr *name,
158 		struct nfs_fh *fhandle, struct nfs_fattr *fattr)
159 {
160 	struct nfs_diropargs	arg = {
161 		.fh		= NFS_FH(dir),
162 		.name		= name->name,
163 		.len		= name->len
164 	};
165 	struct nfs_diropok	res = {
166 		.fh		= fhandle,
167 		.fattr		= fattr
168 	};
169 	struct rpc_message msg = {
170 		.rpc_proc	= &nfs_procedures[NFSPROC_LOOKUP],
171 		.rpc_argp	= &arg,
172 		.rpc_resp	= &res,
173 	};
174 	int			status;
175 	unsigned short task_flags = 0;
176 
177 	/* Is this is an attribute revalidation, subject to softreval? */
178 	if (nfs_lookup_is_soft_revalidate(dentry))
179 		task_flags |= RPC_TASK_TIMEOUT;
180 
181 	dprintk("NFS call  lookup %pd2\n", dentry);
182 	nfs_fattr_init(fattr);
183 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, task_flags);
184 	dprintk("NFS reply lookup: %d\n", status);
185 	return status;
186 }
187 
188 static int nfs_proc_readlink(struct inode *inode, struct page *page,
189 		unsigned int pgbase, unsigned int pglen)
190 {
191 	struct nfs_readlinkargs	args = {
192 		.fh		= NFS_FH(inode),
193 		.pgbase		= pgbase,
194 		.pglen		= pglen,
195 		.pages		= &page
196 	};
197 	struct rpc_message msg = {
198 		.rpc_proc	= &nfs_procedures[NFSPROC_READLINK],
199 		.rpc_argp	= &args,
200 	};
201 	int			status;
202 
203 	dprintk("NFS call  readlink\n");
204 	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
205 	dprintk("NFS reply readlink: %d\n", status);
206 	return status;
207 }
208 
209 struct nfs_createdata {
210 	struct nfs_createargs arg;
211 	struct nfs_diropok res;
212 	struct nfs_fh fhandle;
213 	struct nfs_fattr fattr;
214 };
215 
216 static struct nfs_createdata *nfs_alloc_createdata(struct inode *dir,
217 		struct dentry *dentry, struct iattr *sattr)
218 {
219 	struct nfs_createdata *data;
220 
221 	data = kmalloc_obj(*data);
222 
223 	if (data != NULL) {
224 		data->arg.fh = NFS_FH(dir);
225 		data->arg.name = dentry->d_name.name;
226 		data->arg.len = dentry->d_name.len;
227 		data->arg.sattr = sattr;
228 		nfs_fattr_init(&data->fattr);
229 		data->fhandle.size = 0;
230 		data->res.fh = &data->fhandle;
231 		data->res.fattr = &data->fattr;
232 	}
233 	return data;
234 };
235 
236 static void nfs_free_createdata(const struct nfs_createdata *data)
237 {
238 	kfree(data);
239 }
240 
241 static int
242 nfs_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
243 		int flags)
244 {
245 	struct nfs_createdata *data;
246 	struct rpc_message msg = {
247 		.rpc_proc	= &nfs_procedures[NFSPROC_CREATE],
248 	};
249 	int status = -ENOMEM;
250 
251 	dprintk("NFS call  create %pd\n", dentry);
252 	data = nfs_alloc_createdata(dir, dentry, sattr);
253 	if (data == NULL)
254 		goto out;
255 	msg.rpc_argp = &data->arg;
256 	msg.rpc_resp = &data->res;
257 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
258 	nfs_mark_for_revalidate(dir);
259 	if (status == 0)
260 		status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
261 	nfs_free_createdata(data);
262 out:
263 	dprintk("NFS reply create: %d\n", status);
264 	return status;
265 }
266 
267 /*
268  * In NFSv2, mknod is grafted onto the create call.
269  */
270 static int
271 nfs_proc_mknod(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
272 	       dev_t rdev)
273 {
274 	struct nfs_createdata *data;
275 	struct rpc_message msg = {
276 		.rpc_proc	= &nfs_procedures[NFSPROC_CREATE],
277 	};
278 	umode_t mode;
279 	int status = -ENOMEM;
280 
281 	dprintk("NFS call  mknod %pd\n", dentry);
282 
283 	mode = sattr->ia_mode;
284 	if (S_ISFIFO(mode)) {
285 		sattr->ia_mode = (mode & ~S_IFMT) | S_IFCHR;
286 		sattr->ia_valid &= ~ATTR_SIZE;
287 	} else if (S_ISCHR(mode) || S_ISBLK(mode)) {
288 		sattr->ia_valid |= ATTR_SIZE;
289 		sattr->ia_size = new_encode_dev(rdev);/* get out your barf bag */
290 	}
291 
292 	data = nfs_alloc_createdata(dir, dentry, sattr);
293 	if (data == NULL)
294 		goto out;
295 	msg.rpc_argp = &data->arg;
296 	msg.rpc_resp = &data->res;
297 
298 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
299 	nfs_mark_for_revalidate(dir);
300 
301 	if (status == -EINVAL && S_ISFIFO(mode)) {
302 		sattr->ia_mode = mode;
303 		nfs_fattr_init(data->res.fattr);
304 		status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
305 	}
306 	if (status == 0)
307 		status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
308 	nfs_free_createdata(data);
309 out:
310 	dprintk("NFS reply mknod: %d\n", status);
311 	return status;
312 }
313 
314 static int
315 nfs_proc_remove(struct inode *dir, struct dentry *dentry)
316 {
317 	struct nfs_removeargs arg = {
318 		.fh = NFS_FH(dir),
319 		.name = dentry->d_name,
320 	};
321 	struct rpc_message msg = {
322 		.rpc_proc = &nfs_procedures[NFSPROC_REMOVE],
323 		.rpc_argp = &arg,
324 	};
325 	int			status;
326 
327 	dprintk("NFS call  remove %pd2\n",dentry);
328 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
329 	nfs_mark_for_revalidate(dir);
330 
331 	dprintk("NFS reply remove: %d\n", status);
332 	return status;
333 }
334 
335 static void
336 nfs_proc_unlink_setup(struct rpc_message *msg,
337 		struct dentry *dentry,
338 		struct inode *inode)
339 {
340 	msg->rpc_proc = &nfs_procedures[NFSPROC_REMOVE];
341 }
342 
343 static void nfs_proc_unlink_rpc_prepare(struct rpc_task *task, struct nfs_unlinkdata *data)
344 {
345 	rpc_call_start(task);
346 }
347 
348 static int nfs_proc_unlink_done(struct rpc_task *task, struct inode *dir)
349 {
350 	nfs_mark_for_revalidate(dir);
351 	return 1;
352 }
353 
354 static void
355 nfs_proc_rename_setup(struct rpc_message *msg,
356 		struct dentry *old_dentry,
357 		struct dentry *new_dentry,
358 		struct inode *same_parent)
359 {
360 	msg->rpc_proc = &nfs_procedures[NFSPROC_RENAME];
361 }
362 
363 static void nfs_proc_rename_rpc_prepare(struct rpc_task *task, struct nfs_renamedata *data)
364 {
365 	rpc_call_start(task);
366 }
367 
368 static int
369 nfs_proc_rename_done(struct rpc_task *task, struct inode *old_dir,
370 		     struct inode *new_dir)
371 {
372 	nfs_mark_for_revalidate(old_dir);
373 	nfs_mark_for_revalidate(new_dir);
374 	return 1;
375 }
376 
377 static int
378 nfs_proc_link(struct inode *inode, struct inode *dir, const struct qstr *name)
379 {
380 	struct nfs_linkargs	arg = {
381 		.fromfh		= NFS_FH(inode),
382 		.tofh		= NFS_FH(dir),
383 		.toname		= name->name,
384 		.tolen		= name->len
385 	};
386 	struct rpc_message msg = {
387 		.rpc_proc	= &nfs_procedures[NFSPROC_LINK],
388 		.rpc_argp	= &arg,
389 	};
390 	int			status;
391 
392 	dprintk("NFS call  link %s\n", name->name);
393 	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
394 	nfs_mark_for_revalidate(inode);
395 	nfs_mark_for_revalidate(dir);
396 	dprintk("NFS reply link: %d\n", status);
397 	return status;
398 }
399 
400 static int
401 nfs_proc_symlink(struct inode *dir, struct dentry *dentry, struct folio *folio,
402 		 unsigned int len, struct iattr *sattr)
403 {
404 	struct page *page = &folio->page;
405 	struct nfs_fh *fh;
406 	struct nfs_fattr *fattr;
407 	struct nfs_symlinkargs	arg = {
408 		.fromfh		= NFS_FH(dir),
409 		.fromname	= dentry->d_name.name,
410 		.fromlen	= dentry->d_name.len,
411 		.pages		= &page,
412 		.pathlen	= len,
413 		.sattr		= sattr
414 	};
415 	struct rpc_message msg = {
416 		.rpc_proc	= &nfs_procedures[NFSPROC_SYMLINK],
417 		.rpc_argp	= &arg,
418 	};
419 	int status = -ENAMETOOLONG;
420 
421 	dprintk("NFS call  symlink %pd\n", dentry);
422 
423 	if (len > NFS2_MAXPATHLEN)
424 		goto out;
425 
426 	fh = nfs_alloc_fhandle();
427 	fattr = nfs_alloc_fattr();
428 	status = -ENOMEM;
429 	if (fh == NULL || fattr == NULL)
430 		goto out_free;
431 
432 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
433 	nfs_mark_for_revalidate(dir);
434 
435 	/*
436 	 * V2 SYMLINK requests don't return any attributes.  Setting the
437 	 * filehandle size to zero indicates to nfs_instantiate that it
438 	 * should fill in the data with a LOOKUP call on the wire.
439 	 */
440 	if (status == 0)
441 		status = nfs_instantiate(dentry, fh, fattr);
442 
443 out_free:
444 	nfs_free_fattr(fattr);
445 	nfs_free_fhandle(fh);
446 out:
447 	dprintk("NFS reply symlink: %d\n", status);
448 	return status;
449 }
450 
451 static struct dentry *
452 nfs_proc_mkdir(struct inode *dir, struct dentry *dentry, struct iattr *sattr)
453 {
454 	struct nfs_createdata *data;
455 	struct rpc_message msg = {
456 		.rpc_proc	= &nfs_procedures[NFSPROC_MKDIR],
457 	};
458 	struct dentry *alias = NULL;
459 	int status = -ENOMEM;
460 
461 	dprintk("NFS call  mkdir %pd\n", dentry);
462 	data = nfs_alloc_createdata(dir, dentry, sattr);
463 	if (data == NULL)
464 		goto out;
465 	msg.rpc_argp = &data->arg;
466 	msg.rpc_resp = &data->res;
467 
468 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
469 	nfs_mark_for_revalidate(dir);
470 	if (status == 0) {
471 		alias = nfs_add_or_obtain(dentry, data->res.fh, data->res.fattr);
472 		status = PTR_ERR_OR_ZERO(alias);
473 	} else
474 		alias = ERR_PTR(status);
475 	nfs_free_createdata(data);
476 out:
477 	dprintk("NFS reply mkdir: %d\n", status);
478 	return alias;
479 }
480 
481 static int
482 nfs_proc_rmdir(struct inode *dir, const struct qstr *name)
483 {
484 	struct nfs_diropargs	arg = {
485 		.fh		= NFS_FH(dir),
486 		.name		= name->name,
487 		.len		= name->len
488 	};
489 	struct rpc_message msg = {
490 		.rpc_proc	= &nfs_procedures[NFSPROC_RMDIR],
491 		.rpc_argp	= &arg,
492 	};
493 	int			status;
494 
495 	dprintk("NFS call  rmdir %s\n", name->name);
496 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
497 	nfs_mark_for_revalidate(dir);
498 	dprintk("NFS reply rmdir: %d\n", status);
499 	return status;
500 }
501 
502 /*
503  * The READDIR implementation is somewhat hackish - we pass a temporary
504  * buffer to the encode function, which installs it in the receive
505  * the receive iovec. The decode function just parses the reply to make
506  * sure it is syntactically correct; the entries itself are decoded
507  * from nfs_readdir by calling the decode_entry function directly.
508  */
509 static int nfs_proc_readdir(struct nfs_readdir_arg *nr_arg,
510 			    struct nfs_readdir_res *nr_res)
511 {
512 	struct inode		*dir = d_inode(nr_arg->dentry);
513 	struct nfs_readdirargs	arg = {
514 		.fh		= NFS_FH(dir),
515 		.cookie		= nr_arg->cookie,
516 		.count		= nr_arg->page_len,
517 		.pages		= nr_arg->pages,
518 	};
519 	struct rpc_message	msg = {
520 		.rpc_proc	= &nfs_procedures[NFSPROC_READDIR],
521 		.rpc_argp	= &arg,
522 		.rpc_cred	= nr_arg->cred,
523 	};
524 	int			status;
525 
526 	dprintk("NFS call  readdir %llu\n", (unsigned long long)nr_arg->cookie);
527 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
528 	nr_res->verf[0] = nr_res->verf[1] = 0;
529 
530 	nfs_invalidate_atime(dir);
531 
532 	dprintk("NFS reply readdir: %d\n", status);
533 	return status;
534 }
535 
536 static int
537 nfs_proc_statfs(struct nfs_server *server, struct nfs_fh *fhandle,
538 			struct nfs_fsstat *stat)
539 {
540 	struct nfs2_fsstat fsinfo;
541 	struct rpc_message msg = {
542 		.rpc_proc	= &nfs_procedures[NFSPROC_STATFS],
543 		.rpc_argp	= fhandle,
544 		.rpc_resp	= &fsinfo,
545 	};
546 	int	status;
547 
548 	dprintk("NFS call  statfs\n");
549 	nfs_fattr_init(stat->fattr);
550 	status = rpc_call_sync(server->client, &msg, 0);
551 	dprintk("NFS reply statfs: %d\n", status);
552 	if (status)
553 		goto out;
554 	stat->tbytes = (u64)fsinfo.blocks * fsinfo.bsize;
555 	stat->fbytes = (u64)fsinfo.bfree  * fsinfo.bsize;
556 	stat->abytes = (u64)fsinfo.bavail * fsinfo.bsize;
557 	stat->tfiles = 0;
558 	stat->ffiles = 0;
559 	stat->afiles = 0;
560 out:
561 	return status;
562 }
563 
564 static int
565 nfs_proc_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle,
566 			struct nfs_fsinfo *info)
567 {
568 	struct nfs2_fsstat fsinfo;
569 	struct rpc_message msg = {
570 		.rpc_proc	= &nfs_procedures[NFSPROC_STATFS],
571 		.rpc_argp	= fhandle,
572 		.rpc_resp	= &fsinfo,
573 	};
574 	int	status;
575 
576 	dprintk("NFS call  fsinfo\n");
577 	nfs_fattr_init(info->fattr);
578 	status = rpc_call_sync(server->client, &msg, 0);
579 	dprintk("NFS reply fsinfo: %d\n", status);
580 	if (status)
581 		goto out;
582 	info->rtmax  = NFS_MAXDATA;
583 	info->rtpref = fsinfo.tsize;
584 	info->rtmult = fsinfo.bsize;
585 	info->wtmax  = NFS_MAXDATA;
586 	info->wtpref = fsinfo.tsize;
587 	info->wtmult = fsinfo.bsize;
588 	info->dtpref = fsinfo.tsize;
589 	info->maxfilesize = 0x7FFFFFFF;
590 	info->lease_time = 0;
591 out:
592 	return status;
593 }
594 
595 static int
596 nfs_proc_pathconf(struct nfs_server *server, struct nfs_fh *fhandle,
597 		  struct nfs_pathconf *info)
598 {
599 	info->max_link = 0;
600 	info->max_namelen = NFS2_MAXNAMLEN;
601 	return 0;
602 }
603 
604 static int nfs_read_done(struct rpc_task *task, struct nfs_pgio_header *hdr)
605 {
606 	struct inode *inode = hdr->inode;
607 
608 	nfs_invalidate_atime(inode);
609 	if (task->tk_status >= 0) {
610 		nfs_refresh_inode(inode, hdr->res.fattr);
611 		/* Emulate the eof flag, which isn't normally needed in NFSv2
612 		 * as it is guaranteed to always return the file attributes
613 		 */
614 		if ((hdr->res.count == 0 && hdr->args.count > 0) ||
615 		    hdr->args.offset + hdr->res.count >= hdr->res.fattr->size)
616 			hdr->res.eof = 1;
617 	}
618 	return 0;
619 }
620 
621 static void nfs_proc_read_setup(struct nfs_pgio_header *hdr,
622 				struct rpc_message *msg)
623 {
624 	msg->rpc_proc = &nfs_procedures[NFSPROC_READ];
625 }
626 
627 static int nfs_proc_pgio_rpc_prepare(struct rpc_task *task,
628 				     struct nfs_pgio_header *hdr)
629 {
630 	rpc_call_start(task);
631 	return 0;
632 }
633 
634 static int nfs_write_done(struct rpc_task *task, struct nfs_pgio_header *hdr)
635 {
636 	if (task->tk_status >= 0) {
637 		hdr->res.count = hdr->args.count;
638 		nfs_writeback_update_inode(hdr);
639 	}
640 	return 0;
641 }
642 
643 static void nfs_proc_write_setup(struct nfs_pgio_header *hdr,
644 				 struct rpc_message *msg,
645 				 struct rpc_clnt **clnt)
646 {
647 	/* Note: NFSv2 ignores @stable and always uses NFS_FILE_SYNC */
648 	hdr->args.stable = NFS_FILE_SYNC;
649 	msg->rpc_proc = &nfs_procedures[NFSPROC_WRITE];
650 }
651 
652 static void nfs_proc_commit_rpc_prepare(struct rpc_task *task, struct nfs_commit_data *data)
653 {
654 	BUG();
655 }
656 
657 static void
658 nfs_proc_commit_setup(struct nfs_commit_data *data, struct rpc_message *msg,
659 			struct rpc_clnt **clnt)
660 {
661 	BUG();
662 }
663 
664 static int
665 nfs_proc_lock(struct file *filp, int cmd, struct file_lock *fl)
666 {
667 	struct inode *inode = file_inode(filp);
668 
669 	return nlmclnt_proc(NFS_SERVER(inode)->nlm_host, cmd, fl, NULL);
670 }
671 
672 /* Helper functions for NFS lock bounds checking */
673 #define NFS_LOCK32_OFFSET_MAX ((__s32)0x7fffffffUL)
674 static int nfs_lock_check_bounds(const struct file_lock *fl)
675 {
676 	__s32 start, end;
677 
678 	start = (__s32)fl->fl_start;
679 	if ((loff_t)start != fl->fl_start)
680 		goto out_einval;
681 
682 	if (fl->fl_end != OFFSET_MAX) {
683 		end = (__s32)fl->fl_end;
684 		if ((loff_t)end != fl->fl_end)
685 			goto out_einval;
686 	} else
687 		end = NFS_LOCK32_OFFSET_MAX;
688 
689 	if (start < 0 || start > end)
690 		goto out_einval;
691 	return 0;
692 out_einval:
693 	return -EINVAL;
694 }
695 
696 static int nfs_have_delegation(struct inode *inode, fmode_t type, int flags)
697 {
698 	return 0;
699 }
700 
701 static void nfs_return_delegation(struct inode *inode)
702 {
703 	if (S_ISREG(inode->i_mode))
704 		nfs_wb_all(inode);
705 }
706 
707 static const struct inode_operations nfs_dir_inode_operations = {
708 	.create		= nfs_create,
709 	.lookup		= nfs_lookup,
710 	.atomic_open	= nfs_atomic_open_v23,
711 	.link		= nfs_link,
712 	.unlink		= nfs_unlink,
713 	.symlink	= nfs_symlink,
714 	.mkdir		= nfs_mkdir,
715 	.rmdir		= nfs_rmdir,
716 	.mknod		= nfs_mknod,
717 	.rename		= nfs_rename,
718 	.permission	= nfs_permission,
719 	.getattr	= nfs_getattr,
720 	.setattr	= nfs_setattr,
721 };
722 
723 static const struct inode_operations nfs_file_inode_operations = {
724 	.permission	= nfs_permission,
725 	.getattr	= nfs_getattr,
726 	.setattr	= nfs_setattr,
727 };
728 
729 const struct nfs_rpc_ops nfs_v2_clientops = {
730 	.version	= 2,		       /* protocol version */
731 	.dentry_ops	= &nfs_dentry_operations,
732 	.dir_inode_ops	= &nfs_dir_inode_operations,
733 	.file_inode_ops	= &nfs_file_inode_operations,
734 	.file_ops	= &nfs_file_operations,
735 	.getroot	= nfs_proc_get_root,
736 	.submount	= nfs_submount,
737 	.try_get_tree	= nfs_try_get_tree,
738 	.getattr	= nfs_proc_getattr,
739 	.setattr	= nfs_proc_setattr,
740 	.lookup		= nfs_proc_lookup,
741 	.access		= NULL,		       /* access */
742 	.readlink	= nfs_proc_readlink,
743 	.create		= nfs_proc_create,
744 	.remove		= nfs_proc_remove,
745 	.unlink_setup	= nfs_proc_unlink_setup,
746 	.unlink_rpc_prepare = nfs_proc_unlink_rpc_prepare,
747 	.unlink_done	= nfs_proc_unlink_done,
748 	.rename_setup	= nfs_proc_rename_setup,
749 	.rename_rpc_prepare = nfs_proc_rename_rpc_prepare,
750 	.rename_done	= nfs_proc_rename_done,
751 	.link		= nfs_proc_link,
752 	.symlink	= nfs_proc_symlink,
753 	.mkdir		= nfs_proc_mkdir,
754 	.rmdir		= nfs_proc_rmdir,
755 	.readdir	= nfs_proc_readdir,
756 	.mknod		= nfs_proc_mknod,
757 	.statfs		= nfs_proc_statfs,
758 	.fsinfo		= nfs_proc_fsinfo,
759 	.pathconf	= nfs_proc_pathconf,
760 	.decode_dirent	= nfs2_decode_dirent,
761 	.pgio_rpc_prepare = nfs_proc_pgio_rpc_prepare,
762 	.read_setup	= nfs_proc_read_setup,
763 	.read_done	= nfs_read_done,
764 	.write_setup	= nfs_proc_write_setup,
765 	.write_done	= nfs_write_done,
766 	.commit_setup	= nfs_proc_commit_setup,
767 	.commit_rpc_prepare = nfs_proc_commit_rpc_prepare,
768 	.lock		= nfs_proc_lock,
769 	.lock_check_bounds = nfs_lock_check_bounds,
770 	.close_context	= nfs_close_context,
771 	.have_delegation = nfs_have_delegation,
772 	.return_delegation = nfs_return_delegation,
773 	.alloc_client	= nfs_alloc_client,
774 	.init_client	= nfs_init_client,
775 	.free_client	= nfs_free_client,
776 	.create_server	= nfs_create_server,
777 	.clone_server	= nfs_clone_server,
778 };
779