xref: /openbmc/linux/fs/nfs/proc.c (revision 253a9533)
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/lockd/bind.h>
45 #include <linux/freezer.h>
46 #include "internal.h"
47 
48 #define NFSDBG_FACILITY		NFSDBG_PROC
49 
50 /*
51  * Bare-bones access to getattr: this is for nfs_read_super.
52  */
53 static int
54 nfs_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
55 		  struct nfs_fsinfo *info)
56 {
57 	struct nfs_fattr *fattr = info->fattr;
58 	struct nfs2_fsstat fsinfo;
59 	struct rpc_message msg = {
60 		.rpc_proc	= &nfs_procedures[NFSPROC_GETATTR],
61 		.rpc_argp	= fhandle,
62 		.rpc_resp	= fattr,
63 	};
64 	int status;
65 
66 	dprintk("%s: call getattr\n", __func__);
67 	nfs_fattr_init(fattr);
68 	status = rpc_call_sync(server->client, &msg, 0);
69 	/* Retry with default authentication if different */
70 	if (status && server->nfs_client->cl_rpcclient != server->client)
71 		status = rpc_call_sync(server->nfs_client->cl_rpcclient, &msg, 0);
72 	dprintk("%s: reply getattr: %d\n", __func__, status);
73 	if (status)
74 		return status;
75 	dprintk("%s: call statfs\n", __func__);
76 	msg.rpc_proc = &nfs_procedures[NFSPROC_STATFS];
77 	msg.rpc_resp = &fsinfo;
78 	status = rpc_call_sync(server->client, &msg, 0);
79 	/* Retry with default authentication if different */
80 	if (status && server->nfs_client->cl_rpcclient != server->client)
81 		status = rpc_call_sync(server->nfs_client->cl_rpcclient, &msg, 0);
82 	dprintk("%s: reply statfs: %d\n", __func__, status);
83 	if (status)
84 		return status;
85 	info->rtmax  = NFS_MAXDATA;
86 	info->rtpref = fsinfo.tsize;
87 	info->rtmult = fsinfo.bsize;
88 	info->wtmax  = NFS_MAXDATA;
89 	info->wtpref = fsinfo.tsize;
90 	info->wtmult = fsinfo.bsize;
91 	info->dtpref = fsinfo.tsize;
92 	info->maxfilesize = 0x7FFFFFFF;
93 	info->lease_time = 0;
94 	info->change_attr_type = NFS4_CHANGE_TYPE_IS_UNDEFINED;
95 	info->xattr_support = 0;
96 	return 0;
97 }
98 
99 /*
100  * One function for each procedure in the NFS protocol.
101  */
102 static int
103 nfs_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle,
104 		struct nfs_fattr *fattr, struct nfs4_label *label,
105 		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,
158 		struct nfs_fh *fhandle, struct nfs_fattr *fattr,
159 		struct nfs4_label *label)
160 {
161 	struct nfs_diropargs	arg = {
162 		.fh		= NFS_FH(dir),
163 		.name		= dentry->d_name.name,
164 		.len		= dentry->d_name.len
165 	};
166 	struct nfs_diropok	res = {
167 		.fh		= fhandle,
168 		.fattr		= fattr
169 	};
170 	struct rpc_message msg = {
171 		.rpc_proc	= &nfs_procedures[NFSPROC_LOOKUP],
172 		.rpc_argp	= &arg,
173 		.rpc_resp	= &res,
174 	};
175 	int			status;
176 	unsigned short task_flags = 0;
177 
178 	/* Is this is an attribute revalidation, subject to softreval? */
179 	if (nfs_lookup_is_soft_revalidate(dentry))
180 		task_flags |= RPC_TASK_TIMEOUT;
181 
182 	dprintk("NFS call  lookup %pd2\n", dentry);
183 	nfs_fattr_init(fattr);
184 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, task_flags);
185 	dprintk("NFS reply lookup: %d\n", status);
186 	return status;
187 }
188 
189 static int nfs_proc_readlink(struct inode *inode, struct page *page,
190 		unsigned int pgbase, unsigned int pglen)
191 {
192 	struct nfs_readlinkargs	args = {
193 		.fh		= NFS_FH(inode),
194 		.pgbase		= pgbase,
195 		.pglen		= pglen,
196 		.pages		= &page
197 	};
198 	struct rpc_message msg = {
199 		.rpc_proc	= &nfs_procedures[NFSPROC_READLINK],
200 		.rpc_argp	= &args,
201 	};
202 	int			status;
203 
204 	dprintk("NFS call  readlink\n");
205 	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
206 	dprintk("NFS reply readlink: %d\n", status);
207 	return status;
208 }
209 
210 struct nfs_createdata {
211 	struct nfs_createargs arg;
212 	struct nfs_diropok res;
213 	struct nfs_fh fhandle;
214 	struct nfs_fattr fattr;
215 };
216 
217 static struct nfs_createdata *nfs_alloc_createdata(struct inode *dir,
218 		struct dentry *dentry, struct iattr *sattr)
219 {
220 	struct nfs_createdata *data;
221 
222 	data = kmalloc(sizeof(*data), GFP_KERNEL);
223 
224 	if (data != NULL) {
225 		data->arg.fh = NFS_FH(dir);
226 		data->arg.name = dentry->d_name.name;
227 		data->arg.len = dentry->d_name.len;
228 		data->arg.sattr = sattr;
229 		nfs_fattr_init(&data->fattr);
230 		data->fhandle.size = 0;
231 		data->res.fh = &data->fhandle;
232 		data->res.fattr = &data->fattr;
233 	}
234 	return data;
235 };
236 
237 static void nfs_free_createdata(const struct nfs_createdata *data)
238 {
239 	kfree(data);
240 }
241 
242 static int
243 nfs_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
244 		int flags)
245 {
246 	struct nfs_createdata *data;
247 	struct rpc_message msg = {
248 		.rpc_proc	= &nfs_procedures[NFSPROC_CREATE],
249 	};
250 	int status = -ENOMEM;
251 
252 	dprintk("NFS call  create %pd\n", dentry);
253 	data = nfs_alloc_createdata(dir, dentry, sattr);
254 	if (data == NULL)
255 		goto out;
256 	msg.rpc_argp = &data->arg;
257 	msg.rpc_resp = &data->res;
258 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
259 	nfs_mark_for_revalidate(dir);
260 	if (status == 0)
261 		status = nfs_instantiate(dentry, data->res.fh, data->res.fattr, NULL);
262 	nfs_free_createdata(data);
263 out:
264 	dprintk("NFS reply create: %d\n", status);
265 	return status;
266 }
267 
268 /*
269  * In NFSv2, mknod is grafted onto the create call.
270  */
271 static int
272 nfs_proc_mknod(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
273 	       dev_t rdev)
274 {
275 	struct nfs_createdata *data;
276 	struct rpc_message msg = {
277 		.rpc_proc	= &nfs_procedures[NFSPROC_CREATE],
278 	};
279 	umode_t mode;
280 	int status = -ENOMEM;
281 
282 	dprintk("NFS call  mknod %pd\n", dentry);
283 
284 	mode = sattr->ia_mode;
285 	if (S_ISFIFO(mode)) {
286 		sattr->ia_mode = (mode & ~S_IFMT) | S_IFCHR;
287 		sattr->ia_valid &= ~ATTR_SIZE;
288 	} else if (S_ISCHR(mode) || S_ISBLK(mode)) {
289 		sattr->ia_valid |= ATTR_SIZE;
290 		sattr->ia_size = new_encode_dev(rdev);/* get out your barf bag */
291 	}
292 
293 	data = nfs_alloc_createdata(dir, dentry, sattr);
294 	if (data == NULL)
295 		goto out;
296 	msg.rpc_argp = &data->arg;
297 	msg.rpc_resp = &data->res;
298 
299 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
300 	nfs_mark_for_revalidate(dir);
301 
302 	if (status == -EINVAL && S_ISFIFO(mode)) {
303 		sattr->ia_mode = mode;
304 		nfs_fattr_init(data->res.fattr);
305 		status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
306 	}
307 	if (status == 0)
308 		status = nfs_instantiate(dentry, data->res.fh, data->res.fattr, NULL);
309 	nfs_free_createdata(data);
310 out:
311 	dprintk("NFS reply mknod: %d\n", status);
312 	return status;
313 }
314 
315 static int
316 nfs_proc_remove(struct inode *dir, struct dentry *dentry)
317 {
318 	struct nfs_removeargs arg = {
319 		.fh = NFS_FH(dir),
320 		.name = dentry->d_name,
321 	};
322 	struct rpc_message msg = {
323 		.rpc_proc = &nfs_procedures[NFSPROC_REMOVE],
324 		.rpc_argp = &arg,
325 	};
326 	int			status;
327 
328 	dprintk("NFS call  remove %pd2\n",dentry);
329 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
330 	nfs_mark_for_revalidate(dir);
331 
332 	dprintk("NFS reply remove: %d\n", status);
333 	return status;
334 }
335 
336 static void
337 nfs_proc_unlink_setup(struct rpc_message *msg,
338 		struct dentry *dentry,
339 		struct inode *inode)
340 {
341 	msg->rpc_proc = &nfs_procedures[NFSPROC_REMOVE];
342 }
343 
344 static void nfs_proc_unlink_rpc_prepare(struct rpc_task *task, struct nfs_unlinkdata *data)
345 {
346 	rpc_call_start(task);
347 }
348 
349 static int nfs_proc_unlink_done(struct rpc_task *task, struct inode *dir)
350 {
351 	nfs_mark_for_revalidate(dir);
352 	return 1;
353 }
354 
355 static void
356 nfs_proc_rename_setup(struct rpc_message *msg,
357 		struct dentry *old_dentry,
358 		struct dentry *new_dentry)
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 page *page,
402 		 unsigned int len, struct iattr *sattr)
403 {
404 	struct nfs_fh *fh;
405 	struct nfs_fattr *fattr;
406 	struct nfs_symlinkargs	arg = {
407 		.fromfh		= NFS_FH(dir),
408 		.fromname	= dentry->d_name.name,
409 		.fromlen	= dentry->d_name.len,
410 		.pages		= &page,
411 		.pathlen	= len,
412 		.sattr		= sattr
413 	};
414 	struct rpc_message msg = {
415 		.rpc_proc	= &nfs_procedures[NFSPROC_SYMLINK],
416 		.rpc_argp	= &arg,
417 	};
418 	int status = -ENAMETOOLONG;
419 
420 	dprintk("NFS call  symlink %pd\n", dentry);
421 
422 	if (len > NFS2_MAXPATHLEN)
423 		goto out;
424 
425 	fh = nfs_alloc_fhandle();
426 	fattr = nfs_alloc_fattr();
427 	status = -ENOMEM;
428 	if (fh == NULL || fattr == NULL)
429 		goto out_free;
430 
431 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
432 	nfs_mark_for_revalidate(dir);
433 
434 	/*
435 	 * V2 SYMLINK requests don't return any attributes.  Setting the
436 	 * filehandle size to zero indicates to nfs_instantiate that it
437 	 * should fill in the data with a LOOKUP call on the wire.
438 	 */
439 	if (status == 0)
440 		status = nfs_instantiate(dentry, fh, fattr, NULL);
441 
442 out_free:
443 	nfs_free_fattr(fattr);
444 	nfs_free_fhandle(fh);
445 out:
446 	dprintk("NFS reply symlink: %d\n", status);
447 	return status;
448 }
449 
450 static int
451 nfs_proc_mkdir(struct inode *dir, struct dentry *dentry, struct iattr *sattr)
452 {
453 	struct nfs_createdata *data;
454 	struct rpc_message msg = {
455 		.rpc_proc	= &nfs_procedures[NFSPROC_MKDIR],
456 	};
457 	int status = -ENOMEM;
458 
459 	dprintk("NFS call  mkdir %pd\n", dentry);
460 	data = nfs_alloc_createdata(dir, dentry, sattr);
461 	if (data == NULL)
462 		goto out;
463 	msg.rpc_argp = &data->arg;
464 	msg.rpc_resp = &data->res;
465 
466 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
467 	nfs_mark_for_revalidate(dir);
468 	if (status == 0)
469 		status = nfs_instantiate(dentry, data->res.fh, data->res.fattr, NULL);
470 	nfs_free_createdata(data);
471 out:
472 	dprintk("NFS reply mkdir: %d\n", status);
473 	return status;
474 }
475 
476 static int
477 nfs_proc_rmdir(struct inode *dir, const struct qstr *name)
478 {
479 	struct nfs_diropargs	arg = {
480 		.fh		= NFS_FH(dir),
481 		.name		= name->name,
482 		.len		= name->len
483 	};
484 	struct rpc_message msg = {
485 		.rpc_proc	= &nfs_procedures[NFSPROC_RMDIR],
486 		.rpc_argp	= &arg,
487 	};
488 	int			status;
489 
490 	dprintk("NFS call  rmdir %s\n", name->name);
491 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
492 	nfs_mark_for_revalidate(dir);
493 	dprintk("NFS reply rmdir: %d\n", status);
494 	return status;
495 }
496 
497 /*
498  * The READDIR implementation is somewhat hackish - we pass a temporary
499  * buffer to the encode function, which installs it in the receive
500  * the receive iovec. The decode function just parses the reply to make
501  * sure it is syntactically correct; the entries itself are decoded
502  * from nfs_readdir by calling the decode_entry function directly.
503  */
504 static int nfs_proc_readdir(struct nfs_readdir_arg *nr_arg,
505 			    struct nfs_readdir_res *nr_res)
506 {
507 	struct inode		*dir = d_inode(nr_arg->dentry);
508 	struct nfs_readdirargs	arg = {
509 		.fh		= NFS_FH(dir),
510 		.cookie		= nr_arg->cookie,
511 		.count		= nr_arg->page_len,
512 		.pages		= nr_arg->pages,
513 	};
514 	struct rpc_message	msg = {
515 		.rpc_proc	= &nfs_procedures[NFSPROC_READDIR],
516 		.rpc_argp	= &arg,
517 		.rpc_cred	= nr_arg->cred,
518 	};
519 	int			status;
520 
521 	dprintk("NFS call  readdir %llu\n", (unsigned long long)nr_arg->cookie);
522 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
523 	nr_res->verf[0] = nr_res->verf[1] = 0;
524 
525 	nfs_invalidate_atime(dir);
526 
527 	dprintk("NFS reply readdir: %d\n", status);
528 	return status;
529 }
530 
531 static int
532 nfs_proc_statfs(struct nfs_server *server, struct nfs_fh *fhandle,
533 			struct nfs_fsstat *stat)
534 {
535 	struct nfs2_fsstat fsinfo;
536 	struct rpc_message msg = {
537 		.rpc_proc	= &nfs_procedures[NFSPROC_STATFS],
538 		.rpc_argp	= fhandle,
539 		.rpc_resp	= &fsinfo,
540 	};
541 	int	status;
542 
543 	dprintk("NFS call  statfs\n");
544 	nfs_fattr_init(stat->fattr);
545 	status = rpc_call_sync(server->client, &msg, 0);
546 	dprintk("NFS reply statfs: %d\n", status);
547 	if (status)
548 		goto out;
549 	stat->tbytes = (u64)fsinfo.blocks * fsinfo.bsize;
550 	stat->fbytes = (u64)fsinfo.bfree  * fsinfo.bsize;
551 	stat->abytes = (u64)fsinfo.bavail * fsinfo.bsize;
552 	stat->tfiles = 0;
553 	stat->ffiles = 0;
554 	stat->afiles = 0;
555 out:
556 	return status;
557 }
558 
559 static int
560 nfs_proc_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle,
561 			struct nfs_fsinfo *info)
562 {
563 	struct nfs2_fsstat fsinfo;
564 	struct rpc_message msg = {
565 		.rpc_proc	= &nfs_procedures[NFSPROC_STATFS],
566 		.rpc_argp	= fhandle,
567 		.rpc_resp	= &fsinfo,
568 	};
569 	int	status;
570 
571 	dprintk("NFS call  fsinfo\n");
572 	nfs_fattr_init(info->fattr);
573 	status = rpc_call_sync(server->client, &msg, 0);
574 	dprintk("NFS reply fsinfo: %d\n", status);
575 	if (status)
576 		goto out;
577 	info->rtmax  = NFS_MAXDATA;
578 	info->rtpref = fsinfo.tsize;
579 	info->rtmult = fsinfo.bsize;
580 	info->wtmax  = NFS_MAXDATA;
581 	info->wtpref = fsinfo.tsize;
582 	info->wtmult = fsinfo.bsize;
583 	info->dtpref = fsinfo.tsize;
584 	info->maxfilesize = 0x7FFFFFFF;
585 	info->lease_time = 0;
586 out:
587 	return status;
588 }
589 
590 static int
591 nfs_proc_pathconf(struct nfs_server *server, struct nfs_fh *fhandle,
592 		  struct nfs_pathconf *info)
593 {
594 	info->max_link = 0;
595 	info->max_namelen = NFS2_MAXNAMLEN;
596 	return 0;
597 }
598 
599 static int nfs_read_done(struct rpc_task *task, struct nfs_pgio_header *hdr)
600 {
601 	struct inode *inode = hdr->inode;
602 
603 	nfs_invalidate_atime(inode);
604 	if (task->tk_status >= 0) {
605 		nfs_refresh_inode(inode, hdr->res.fattr);
606 		/* Emulate the eof flag, which isn't normally needed in NFSv2
607 		 * as it is guaranteed to always return the file attributes
608 		 */
609 		if ((hdr->res.count == 0 && hdr->args.count > 0) ||
610 		    hdr->args.offset + hdr->res.count >= hdr->res.fattr->size)
611 			hdr->res.eof = 1;
612 	}
613 	return 0;
614 }
615 
616 static void nfs_proc_read_setup(struct nfs_pgio_header *hdr,
617 				struct rpc_message *msg)
618 {
619 	msg->rpc_proc = &nfs_procedures[NFSPROC_READ];
620 }
621 
622 static int nfs_proc_pgio_rpc_prepare(struct rpc_task *task,
623 				     struct nfs_pgio_header *hdr)
624 {
625 	rpc_call_start(task);
626 	return 0;
627 }
628 
629 static int nfs_write_done(struct rpc_task *task, struct nfs_pgio_header *hdr)
630 {
631 	if (task->tk_status >= 0) {
632 		hdr->res.count = hdr->args.count;
633 		nfs_writeback_update_inode(hdr);
634 	}
635 	return 0;
636 }
637 
638 static void nfs_proc_write_setup(struct nfs_pgio_header *hdr,
639 				 struct rpc_message *msg,
640 				 struct rpc_clnt **clnt)
641 {
642 	/* Note: NFSv2 ignores @stable and always uses NFS_FILE_SYNC */
643 	hdr->args.stable = NFS_FILE_SYNC;
644 	msg->rpc_proc = &nfs_procedures[NFSPROC_WRITE];
645 }
646 
647 static void nfs_proc_commit_rpc_prepare(struct rpc_task *task, struct nfs_commit_data *data)
648 {
649 	BUG();
650 }
651 
652 static void
653 nfs_proc_commit_setup(struct nfs_commit_data *data, struct rpc_message *msg,
654 			struct rpc_clnt **clnt)
655 {
656 	BUG();
657 }
658 
659 static int
660 nfs_proc_lock(struct file *filp, int cmd, struct file_lock *fl)
661 {
662 	struct inode *inode = file_inode(filp);
663 
664 	return nlmclnt_proc(NFS_SERVER(inode)->nlm_host, cmd, fl, NULL);
665 }
666 
667 /* Helper functions for NFS lock bounds checking */
668 #define NFS_LOCK32_OFFSET_MAX ((__s32)0x7fffffffUL)
669 static int nfs_lock_check_bounds(const struct file_lock *fl)
670 {
671 	__s32 start, end;
672 
673 	start = (__s32)fl->fl_start;
674 	if ((loff_t)start != fl->fl_start)
675 		goto out_einval;
676 
677 	if (fl->fl_end != OFFSET_MAX) {
678 		end = (__s32)fl->fl_end;
679 		if ((loff_t)end != fl->fl_end)
680 			goto out_einval;
681 	} else
682 		end = NFS_LOCK32_OFFSET_MAX;
683 
684 	if (start < 0 || start > end)
685 		goto out_einval;
686 	return 0;
687 out_einval:
688 	return -EINVAL;
689 }
690 
691 static int nfs_have_delegation(struct inode *inode, fmode_t flags)
692 {
693 	return 0;
694 }
695 
696 static const struct inode_operations nfs_dir_inode_operations = {
697 	.create		= nfs_create,
698 	.lookup		= nfs_lookup,
699 	.link		= nfs_link,
700 	.unlink		= nfs_unlink,
701 	.symlink	= nfs_symlink,
702 	.mkdir		= nfs_mkdir,
703 	.rmdir		= nfs_rmdir,
704 	.mknod		= nfs_mknod,
705 	.rename		= nfs_rename,
706 	.permission	= nfs_permission,
707 	.getattr	= nfs_getattr,
708 	.setattr	= nfs_setattr,
709 };
710 
711 static const struct inode_operations nfs_file_inode_operations = {
712 	.permission	= nfs_permission,
713 	.getattr	= nfs_getattr,
714 	.setattr	= nfs_setattr,
715 };
716 
717 const struct nfs_rpc_ops nfs_v2_clientops = {
718 	.version	= 2,		       /* protocol version */
719 	.dentry_ops	= &nfs_dentry_operations,
720 	.dir_inode_ops	= &nfs_dir_inode_operations,
721 	.file_inode_ops	= &nfs_file_inode_operations,
722 	.file_ops	= &nfs_file_operations,
723 	.getroot	= nfs_proc_get_root,
724 	.submount	= nfs_submount,
725 	.try_get_tree	= nfs_try_get_tree,
726 	.getattr	= nfs_proc_getattr,
727 	.setattr	= nfs_proc_setattr,
728 	.lookup		= nfs_proc_lookup,
729 	.access		= NULL,		       /* access */
730 	.readlink	= nfs_proc_readlink,
731 	.create		= nfs_proc_create,
732 	.remove		= nfs_proc_remove,
733 	.unlink_setup	= nfs_proc_unlink_setup,
734 	.unlink_rpc_prepare = nfs_proc_unlink_rpc_prepare,
735 	.unlink_done	= nfs_proc_unlink_done,
736 	.rename_setup	= nfs_proc_rename_setup,
737 	.rename_rpc_prepare = nfs_proc_rename_rpc_prepare,
738 	.rename_done	= nfs_proc_rename_done,
739 	.link		= nfs_proc_link,
740 	.symlink	= nfs_proc_symlink,
741 	.mkdir		= nfs_proc_mkdir,
742 	.rmdir		= nfs_proc_rmdir,
743 	.readdir	= nfs_proc_readdir,
744 	.mknod		= nfs_proc_mknod,
745 	.statfs		= nfs_proc_statfs,
746 	.fsinfo		= nfs_proc_fsinfo,
747 	.pathconf	= nfs_proc_pathconf,
748 	.decode_dirent	= nfs2_decode_dirent,
749 	.pgio_rpc_prepare = nfs_proc_pgio_rpc_prepare,
750 	.read_setup	= nfs_proc_read_setup,
751 	.read_done	= nfs_read_done,
752 	.write_setup	= nfs_proc_write_setup,
753 	.write_done	= nfs_write_done,
754 	.commit_setup	= nfs_proc_commit_setup,
755 	.commit_rpc_prepare = nfs_proc_commit_rpc_prepare,
756 	.lock		= nfs_proc_lock,
757 	.lock_check_bounds = nfs_lock_check_bounds,
758 	.close_context	= nfs_close_context,
759 	.have_delegation = nfs_have_delegation,
760 	.alloc_client	= nfs_alloc_client,
761 	.init_client	= nfs_init_client,
762 	.free_client	= nfs_free_client,
763 	.create_server	= nfs_create_server,
764 	.clone_server	= nfs_clone_server,
765 };
766