xref: /linux/fs/nfs/proc.c (revision d524dac9279b6a41ffdf7ff7958c577f2e387db6)
1 /*
2  *  linux/fs/nfs/proc.c
3  *
4  *  Copyright (C) 1992, 1993, 1994  Rick Sladkey
5  *
6  *  OS-independent nfs remote procedure call functions
7  *
8  *  Tuned by Alan Cox <A.Cox@swansea.ac.uk> for >3K buffers
9  *  so at last we can have decent(ish) throughput off a
10  *  Sun server.
11  *
12  *  Coding optimized and cleaned up by Florian La Roche.
13  *  Note: Error returns are optimized for NFS_OK, which isn't translated via
14  *  nfs_stat_to_errno(), but happens to be already the right return code.
15  *
16  *  Also, the code currently doesn't check the size of the packet, when
17  *  it decodes the packet.
18  *
19  *  Feel free to fix it and mail me the diffs if it worries you.
20  *
21  *  Completely rewritten to support the new RPC call interface;
22  *  rewrote and moved the entire XDR stuff to xdr.c
23  *  --Olaf Kirch June 1996
24  *
25  *  The code below initializes all auto variables explicitly, otherwise
26  *  it will fail to work as a module (gcc generates a memset call for an
27  *  incomplete struct).
28  */
29 
30 #include <linux/types.h>
31 #include <linux/param.h>
32 #include <linux/time.h>
33 #include <linux/mm.h>
34 #include <linux/errno.h>
35 #include <linux/string.h>
36 #include <linux/in.h>
37 #include <linux/pagemap.h>
38 #include <linux/sunrpc/clnt.h>
39 #include <linux/nfs.h>
40 #include <linux/nfs2.h>
41 #include <linux/nfs_fs.h>
42 #include <linux/nfs_page.h>
43 #include <linux/lockd/bind.h>
44 #include "internal.h"
45 
46 #define NFSDBG_FACILITY		NFSDBG_PROC
47 
48 /*
49  * wrapper to handle the -EKEYEXPIRED error message. This should generally
50  * only happen if using krb5 auth and a user's TGT expires. NFSv2 doesn't
51  * support the NFSERR_JUKEBOX error code, but we handle this situation in the
52  * same way that we handle that error with NFSv3.
53  */
54 static int
55 nfs_rpc_wrapper(struct rpc_clnt *clnt, struct rpc_message *msg, int flags)
56 {
57 	int res;
58 	do {
59 		res = rpc_call_sync(clnt, msg, flags);
60 		if (res != -EKEYEXPIRED)
61 			break;
62 		schedule_timeout_killable(NFS_JUKEBOX_RETRY_TIME);
63 		res = -ERESTARTSYS;
64 	} while (!fatal_signal_pending(current));
65 	return res;
66 }
67 
68 #define rpc_call_sync(clnt, msg, flags)	nfs_rpc_wrapper(clnt, msg, flags)
69 
70 static int
71 nfs_async_handle_expired_key(struct rpc_task *task)
72 {
73 	if (task->tk_status != -EKEYEXPIRED)
74 		return 0;
75 	task->tk_status = 0;
76 	rpc_restart_call(task);
77 	rpc_delay(task, NFS_JUKEBOX_RETRY_TIME);
78 	return 1;
79 }
80 
81 /*
82  * Bare-bones access to getattr: this is for nfs_read_super.
83  */
84 static int
85 nfs_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
86 		  struct nfs_fsinfo *info)
87 {
88 	struct nfs_fattr *fattr = info->fattr;
89 	struct nfs2_fsstat fsinfo;
90 	struct rpc_message msg = {
91 		.rpc_proc	= &nfs_procedures[NFSPROC_GETATTR],
92 		.rpc_argp	= fhandle,
93 		.rpc_resp	= fattr,
94 	};
95 	int status;
96 
97 	dprintk("%s: call getattr\n", __func__);
98 	nfs_fattr_init(fattr);
99 	status = rpc_call_sync(server->client, &msg, 0);
100 	/* Retry with default authentication if different */
101 	if (status && server->nfs_client->cl_rpcclient != server->client)
102 		status = rpc_call_sync(server->nfs_client->cl_rpcclient, &msg, 0);
103 	dprintk("%s: reply getattr: %d\n", __func__, status);
104 	if (status)
105 		return status;
106 	dprintk("%s: call statfs\n", __func__);
107 	msg.rpc_proc = &nfs_procedures[NFSPROC_STATFS];
108 	msg.rpc_resp = &fsinfo;
109 	status = rpc_call_sync(server->client, &msg, 0);
110 	/* Retry with default authentication if different */
111 	if (status && server->nfs_client->cl_rpcclient != server->client)
112 		status = rpc_call_sync(server->nfs_client->cl_rpcclient, &msg, 0);
113 	dprintk("%s: reply statfs: %d\n", __func__, status);
114 	if (status)
115 		return status;
116 	info->rtmax  = NFS_MAXDATA;
117 	info->rtpref = fsinfo.tsize;
118 	info->rtmult = fsinfo.bsize;
119 	info->wtmax  = NFS_MAXDATA;
120 	info->wtpref = fsinfo.tsize;
121 	info->wtmult = fsinfo.bsize;
122 	info->dtpref = fsinfo.tsize;
123 	info->maxfilesize = 0x7FFFFFFF;
124 	info->lease_time = 0;
125 	return 0;
126 }
127 
128 /*
129  * One function for each procedure in the NFS protocol.
130  */
131 static int
132 nfs_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle,
133 		struct nfs_fattr *fattr)
134 {
135 	struct rpc_message msg = {
136 		.rpc_proc	= &nfs_procedures[NFSPROC_GETATTR],
137 		.rpc_argp	= fhandle,
138 		.rpc_resp	= fattr,
139 	};
140 	int	status;
141 
142 	dprintk("NFS call  getattr\n");
143 	nfs_fattr_init(fattr);
144 	status = rpc_call_sync(server->client, &msg, 0);
145 	dprintk("NFS reply getattr: %d\n", status);
146 	return status;
147 }
148 
149 static int
150 nfs_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
151 		 struct iattr *sattr)
152 {
153 	struct inode *inode = dentry->d_inode;
154 	struct nfs_sattrargs	arg = {
155 		.fh	= NFS_FH(inode),
156 		.sattr	= sattr
157 	};
158 	struct rpc_message msg = {
159 		.rpc_proc	= &nfs_procedures[NFSPROC_SETATTR],
160 		.rpc_argp	= &arg,
161 		.rpc_resp	= fattr,
162 	};
163 	int	status;
164 
165 	/* Mask out the non-modebit related stuff from attr->ia_mode */
166 	sattr->ia_mode &= S_IALLUGO;
167 
168 	dprintk("NFS call  setattr\n");
169 	if (sattr->ia_valid & ATTR_FILE)
170 		msg.rpc_cred = nfs_file_cred(sattr->ia_file);
171 	nfs_fattr_init(fattr);
172 	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
173 	if (status == 0)
174 		nfs_setattr_update_inode(inode, sattr);
175 	dprintk("NFS reply setattr: %d\n", status);
176 	return status;
177 }
178 
179 static int
180 nfs_proc_lookup(struct inode *dir, struct qstr *name,
181 		struct nfs_fh *fhandle, struct nfs_fattr *fattr)
182 {
183 	struct nfs_diropargs	arg = {
184 		.fh		= NFS_FH(dir),
185 		.name		= name->name,
186 		.len		= name->len
187 	};
188 	struct nfs_diropok	res = {
189 		.fh		= fhandle,
190 		.fattr		= fattr
191 	};
192 	struct rpc_message msg = {
193 		.rpc_proc	= &nfs_procedures[NFSPROC_LOOKUP],
194 		.rpc_argp	= &arg,
195 		.rpc_resp	= &res,
196 	};
197 	int			status;
198 
199 	dprintk("NFS call  lookup %s\n", name->name);
200 	nfs_fattr_init(fattr);
201 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
202 	dprintk("NFS reply lookup: %d\n", status);
203 	return status;
204 }
205 
206 static int nfs_proc_readlink(struct inode *inode, struct page *page,
207 		unsigned int pgbase, unsigned int pglen)
208 {
209 	struct nfs_readlinkargs	args = {
210 		.fh		= NFS_FH(inode),
211 		.pgbase		= pgbase,
212 		.pglen		= pglen,
213 		.pages		= &page
214 	};
215 	struct rpc_message msg = {
216 		.rpc_proc	= &nfs_procedures[NFSPROC_READLINK],
217 		.rpc_argp	= &args,
218 	};
219 	int			status;
220 
221 	dprintk("NFS call  readlink\n");
222 	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
223 	dprintk("NFS reply readlink: %d\n", status);
224 	return status;
225 }
226 
227 struct nfs_createdata {
228 	struct nfs_createargs arg;
229 	struct nfs_diropok res;
230 	struct nfs_fh fhandle;
231 	struct nfs_fattr fattr;
232 };
233 
234 static struct nfs_createdata *nfs_alloc_createdata(struct inode *dir,
235 		struct dentry *dentry, struct iattr *sattr)
236 {
237 	struct nfs_createdata *data;
238 
239 	data = kmalloc(sizeof(*data), GFP_KERNEL);
240 
241 	if (data != NULL) {
242 		data->arg.fh = NFS_FH(dir);
243 		data->arg.name = dentry->d_name.name;
244 		data->arg.len = dentry->d_name.len;
245 		data->arg.sattr = sattr;
246 		nfs_fattr_init(&data->fattr);
247 		data->fhandle.size = 0;
248 		data->res.fh = &data->fhandle;
249 		data->res.fattr = &data->fattr;
250 	}
251 	return data;
252 };
253 
254 static void nfs_free_createdata(const struct nfs_createdata *data)
255 {
256 	kfree(data);
257 }
258 
259 static int
260 nfs_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
261 		int flags, struct nfs_open_context *ctx)
262 {
263 	struct nfs_createdata *data;
264 	struct rpc_message msg = {
265 		.rpc_proc	= &nfs_procedures[NFSPROC_CREATE],
266 	};
267 	int status = -ENOMEM;
268 
269 	dprintk("NFS call  create %s\n", dentry->d_name.name);
270 	data = nfs_alloc_createdata(dir, dentry, sattr);
271 	if (data == NULL)
272 		goto out;
273 	msg.rpc_argp = &data->arg;
274 	msg.rpc_resp = &data->res;
275 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
276 	nfs_mark_for_revalidate(dir);
277 	if (status == 0)
278 		status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
279 	nfs_free_createdata(data);
280 out:
281 	dprintk("NFS reply create: %d\n", status);
282 	return status;
283 }
284 
285 /*
286  * In NFSv2, mknod is grafted onto the create call.
287  */
288 static int
289 nfs_proc_mknod(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
290 	       dev_t rdev)
291 {
292 	struct nfs_createdata *data;
293 	struct rpc_message msg = {
294 		.rpc_proc	= &nfs_procedures[NFSPROC_CREATE],
295 	};
296 	umode_t mode;
297 	int status = -ENOMEM;
298 
299 	dprintk("NFS call  mknod %s\n", dentry->d_name.name);
300 
301 	mode = sattr->ia_mode;
302 	if (S_ISFIFO(mode)) {
303 		sattr->ia_mode = (mode & ~S_IFMT) | S_IFCHR;
304 		sattr->ia_valid &= ~ATTR_SIZE;
305 	} else if (S_ISCHR(mode) || S_ISBLK(mode)) {
306 		sattr->ia_valid |= ATTR_SIZE;
307 		sattr->ia_size = new_encode_dev(rdev);/* get out your barf bag */
308 	}
309 
310 	data = nfs_alloc_createdata(dir, dentry, sattr);
311 	if (data == NULL)
312 		goto out;
313 	msg.rpc_argp = &data->arg;
314 	msg.rpc_resp = &data->res;
315 
316 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
317 	nfs_mark_for_revalidate(dir);
318 
319 	if (status == -EINVAL && S_ISFIFO(mode)) {
320 		sattr->ia_mode = mode;
321 		nfs_fattr_init(data->res.fattr);
322 		status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
323 	}
324 	if (status == 0)
325 		status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
326 	nfs_free_createdata(data);
327 out:
328 	dprintk("NFS reply mknod: %d\n", status);
329 	return status;
330 }
331 
332 static int
333 nfs_proc_remove(struct inode *dir, struct qstr *name)
334 {
335 	struct nfs_removeargs arg = {
336 		.fh = NFS_FH(dir),
337 		.name.len = name->len,
338 		.name.name = name->name,
339 	};
340 	struct rpc_message msg = {
341 		.rpc_proc = &nfs_procedures[NFSPROC_REMOVE],
342 		.rpc_argp = &arg,
343 	};
344 	int			status;
345 
346 	dprintk("NFS call  remove %s\n", name->name);
347 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
348 	nfs_mark_for_revalidate(dir);
349 
350 	dprintk("NFS reply remove: %d\n", status);
351 	return status;
352 }
353 
354 static void
355 nfs_proc_unlink_setup(struct rpc_message *msg, struct inode *dir)
356 {
357 	msg->rpc_proc = &nfs_procedures[NFSPROC_REMOVE];
358 }
359 
360 static int nfs_proc_unlink_done(struct rpc_task *task, struct inode *dir)
361 {
362 	if (nfs_async_handle_expired_key(task))
363 		return 0;
364 	nfs_mark_for_revalidate(dir);
365 	return 1;
366 }
367 
368 static void
369 nfs_proc_rename_setup(struct rpc_message *msg, struct inode *dir)
370 {
371 	msg->rpc_proc = &nfs_procedures[NFSPROC_RENAME];
372 }
373 
374 static int
375 nfs_proc_rename_done(struct rpc_task *task, struct inode *old_dir,
376 		     struct inode *new_dir)
377 {
378 	if (nfs_async_handle_expired_key(task))
379 		return 0;
380 	nfs_mark_for_revalidate(old_dir);
381 	nfs_mark_for_revalidate(new_dir);
382 	return 1;
383 }
384 
385 static int
386 nfs_proc_rename(struct inode *old_dir, struct qstr *old_name,
387 		struct inode *new_dir, struct qstr *new_name)
388 {
389 	struct nfs_renameargs	arg = {
390 		.old_dir	= NFS_FH(old_dir),
391 		.old_name	= old_name,
392 		.new_dir	= NFS_FH(new_dir),
393 		.new_name	= new_name,
394 	};
395 	struct rpc_message msg = {
396 		.rpc_proc	= &nfs_procedures[NFSPROC_RENAME],
397 		.rpc_argp	= &arg,
398 	};
399 	int			status;
400 
401 	dprintk("NFS call  rename %s -> %s\n", old_name->name, new_name->name);
402 	status = rpc_call_sync(NFS_CLIENT(old_dir), &msg, 0);
403 	nfs_mark_for_revalidate(old_dir);
404 	nfs_mark_for_revalidate(new_dir);
405 	dprintk("NFS reply rename: %d\n", status);
406 	return status;
407 }
408 
409 static int
410 nfs_proc_link(struct inode *inode, struct inode *dir, struct qstr *name)
411 {
412 	struct nfs_linkargs	arg = {
413 		.fromfh		= NFS_FH(inode),
414 		.tofh		= NFS_FH(dir),
415 		.toname		= name->name,
416 		.tolen		= name->len
417 	};
418 	struct rpc_message msg = {
419 		.rpc_proc	= &nfs_procedures[NFSPROC_LINK],
420 		.rpc_argp	= &arg,
421 	};
422 	int			status;
423 
424 	dprintk("NFS call  link %s\n", name->name);
425 	status = rpc_call_sync(NFS_CLIENT(inode), &msg, 0);
426 	nfs_mark_for_revalidate(inode);
427 	nfs_mark_for_revalidate(dir);
428 	dprintk("NFS reply link: %d\n", status);
429 	return status;
430 }
431 
432 static int
433 nfs_proc_symlink(struct inode *dir, struct dentry *dentry, struct page *page,
434 		 unsigned int len, struct iattr *sattr)
435 {
436 	struct nfs_fh *fh;
437 	struct nfs_fattr *fattr;
438 	struct nfs_symlinkargs	arg = {
439 		.fromfh		= NFS_FH(dir),
440 		.fromname	= dentry->d_name.name,
441 		.fromlen	= dentry->d_name.len,
442 		.pages		= &page,
443 		.pathlen	= len,
444 		.sattr		= sattr
445 	};
446 	struct rpc_message msg = {
447 		.rpc_proc	= &nfs_procedures[NFSPROC_SYMLINK],
448 		.rpc_argp	= &arg,
449 	};
450 	int status = -ENAMETOOLONG;
451 
452 	dprintk("NFS call  symlink %s\n", dentry->d_name.name);
453 
454 	if (len > NFS2_MAXPATHLEN)
455 		goto out;
456 
457 	fh = nfs_alloc_fhandle();
458 	fattr = nfs_alloc_fattr();
459 	status = -ENOMEM;
460 	if (fh == NULL || fattr == NULL)
461 		goto out_free;
462 
463 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
464 	nfs_mark_for_revalidate(dir);
465 
466 	/*
467 	 * V2 SYMLINK requests don't return any attributes.  Setting the
468 	 * filehandle size to zero indicates to nfs_instantiate that it
469 	 * should fill in the data with a LOOKUP call on the wire.
470 	 */
471 	if (status == 0)
472 		status = nfs_instantiate(dentry, fh, fattr);
473 
474 out_free:
475 	nfs_free_fattr(fattr);
476 	nfs_free_fhandle(fh);
477 out:
478 	dprintk("NFS reply symlink: %d\n", status);
479 	return status;
480 }
481 
482 static int
483 nfs_proc_mkdir(struct inode *dir, struct dentry *dentry, struct iattr *sattr)
484 {
485 	struct nfs_createdata *data;
486 	struct rpc_message msg = {
487 		.rpc_proc	= &nfs_procedures[NFSPROC_MKDIR],
488 	};
489 	int status = -ENOMEM;
490 
491 	dprintk("NFS call  mkdir %s\n", dentry->d_name.name);
492 	data = nfs_alloc_createdata(dir, dentry, sattr);
493 	if (data == NULL)
494 		goto out;
495 	msg.rpc_argp = &data->arg;
496 	msg.rpc_resp = &data->res;
497 
498 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
499 	nfs_mark_for_revalidate(dir);
500 	if (status == 0)
501 		status = nfs_instantiate(dentry, data->res.fh, data->res.fattr);
502 	nfs_free_createdata(data);
503 out:
504 	dprintk("NFS reply mkdir: %d\n", status);
505 	return status;
506 }
507 
508 static int
509 nfs_proc_rmdir(struct inode *dir, struct qstr *name)
510 {
511 	struct nfs_diropargs	arg = {
512 		.fh		= NFS_FH(dir),
513 		.name		= name->name,
514 		.len		= name->len
515 	};
516 	struct rpc_message msg = {
517 		.rpc_proc	= &nfs_procedures[NFSPROC_RMDIR],
518 		.rpc_argp	= &arg,
519 	};
520 	int			status;
521 
522 	dprintk("NFS call  rmdir %s\n", name->name);
523 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
524 	nfs_mark_for_revalidate(dir);
525 	dprintk("NFS reply rmdir: %d\n", status);
526 	return status;
527 }
528 
529 /*
530  * The READDIR implementation is somewhat hackish - we pass a temporary
531  * buffer to the encode function, which installs it in the receive
532  * the receive iovec. The decode function just parses the reply to make
533  * sure it is syntactically correct; the entries itself are decoded
534  * from nfs_readdir by calling the decode_entry function directly.
535  */
536 static int
537 nfs_proc_readdir(struct dentry *dentry, struct rpc_cred *cred,
538 		 u64 cookie, struct page **pages, unsigned int count, int plus)
539 {
540 	struct inode		*dir = dentry->d_inode;
541 	struct nfs_readdirargs	arg = {
542 		.fh		= NFS_FH(dir),
543 		.cookie		= cookie,
544 		.count		= count,
545 		.pages		= pages,
546 	};
547 	struct rpc_message	msg = {
548 		.rpc_proc	= &nfs_procedures[NFSPROC_READDIR],
549 		.rpc_argp	= &arg,
550 		.rpc_cred	= cred,
551 	};
552 	int			status;
553 
554 	dprintk("NFS call  readdir %d\n", (unsigned int)cookie);
555 	status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
556 
557 	nfs_invalidate_atime(dir);
558 
559 	dprintk("NFS reply readdir: %d\n", status);
560 	return status;
561 }
562 
563 static int
564 nfs_proc_statfs(struct nfs_server *server, struct nfs_fh *fhandle,
565 			struct nfs_fsstat *stat)
566 {
567 	struct nfs2_fsstat fsinfo;
568 	struct rpc_message msg = {
569 		.rpc_proc	= &nfs_procedures[NFSPROC_STATFS],
570 		.rpc_argp	= fhandle,
571 		.rpc_resp	= &fsinfo,
572 	};
573 	int	status;
574 
575 	dprintk("NFS call  statfs\n");
576 	nfs_fattr_init(stat->fattr);
577 	status = rpc_call_sync(server->client, &msg, 0);
578 	dprintk("NFS reply statfs: %d\n", status);
579 	if (status)
580 		goto out;
581 	stat->tbytes = (u64)fsinfo.blocks * fsinfo.bsize;
582 	stat->fbytes = (u64)fsinfo.bfree  * fsinfo.bsize;
583 	stat->abytes = (u64)fsinfo.bavail * fsinfo.bsize;
584 	stat->tfiles = 0;
585 	stat->ffiles = 0;
586 	stat->afiles = 0;
587 out:
588 	return status;
589 }
590 
591 static int
592 nfs_proc_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle,
593 			struct nfs_fsinfo *info)
594 {
595 	struct nfs2_fsstat fsinfo;
596 	struct rpc_message msg = {
597 		.rpc_proc	= &nfs_procedures[NFSPROC_STATFS],
598 		.rpc_argp	= fhandle,
599 		.rpc_resp	= &fsinfo,
600 	};
601 	int	status;
602 
603 	dprintk("NFS call  fsinfo\n");
604 	nfs_fattr_init(info->fattr);
605 	status = rpc_call_sync(server->client, &msg, 0);
606 	dprintk("NFS reply fsinfo: %d\n", status);
607 	if (status)
608 		goto out;
609 	info->rtmax  = NFS_MAXDATA;
610 	info->rtpref = fsinfo.tsize;
611 	info->rtmult = fsinfo.bsize;
612 	info->wtmax  = NFS_MAXDATA;
613 	info->wtpref = fsinfo.tsize;
614 	info->wtmult = fsinfo.bsize;
615 	info->dtpref = fsinfo.tsize;
616 	info->maxfilesize = 0x7FFFFFFF;
617 	info->lease_time = 0;
618 out:
619 	return status;
620 }
621 
622 static int
623 nfs_proc_pathconf(struct nfs_server *server, struct nfs_fh *fhandle,
624 		  struct nfs_pathconf *info)
625 {
626 	info->max_link = 0;
627 	info->max_namelen = NFS2_MAXNAMLEN;
628 	return 0;
629 }
630 
631 static int nfs_read_done(struct rpc_task *task, struct nfs_read_data *data)
632 {
633 	if (nfs_async_handle_expired_key(task))
634 		return -EAGAIN;
635 
636 	nfs_invalidate_atime(data->inode);
637 	if (task->tk_status >= 0) {
638 		nfs_refresh_inode(data->inode, data->res.fattr);
639 		/* Emulate the eof flag, which isn't normally needed in NFSv2
640 		 * as it is guaranteed to always return the file attributes
641 		 */
642 		if (data->args.offset + data->args.count >= data->res.fattr->size)
643 			data->res.eof = 1;
644 	}
645 	return 0;
646 }
647 
648 static void nfs_proc_read_setup(struct nfs_read_data *data, struct rpc_message *msg)
649 {
650 	msg->rpc_proc = &nfs_procedures[NFSPROC_READ];
651 }
652 
653 static int nfs_write_done(struct rpc_task *task, struct nfs_write_data *data)
654 {
655 	if (nfs_async_handle_expired_key(task))
656 		return -EAGAIN;
657 
658 	if (task->tk_status >= 0)
659 		nfs_post_op_update_inode_force_wcc(data->inode, data->res.fattr);
660 	return 0;
661 }
662 
663 static void nfs_proc_write_setup(struct nfs_write_data *data, struct rpc_message *msg)
664 {
665 	/* Note: NFSv2 ignores @stable and always uses NFS_FILE_SYNC */
666 	data->args.stable = NFS_FILE_SYNC;
667 	msg->rpc_proc = &nfs_procedures[NFSPROC_WRITE];
668 }
669 
670 static void
671 nfs_proc_commit_setup(struct nfs_write_data *data, struct rpc_message *msg)
672 {
673 	BUG();
674 }
675 
676 static int
677 nfs_proc_lock(struct file *filp, int cmd, struct file_lock *fl)
678 {
679 	struct inode *inode = filp->f_path.dentry->d_inode;
680 
681 	return nlmclnt_proc(NFS_SERVER(inode)->nlm_host, cmd, fl);
682 }
683 
684 /* Helper functions for NFS lock bounds checking */
685 #define NFS_LOCK32_OFFSET_MAX ((__s32)0x7fffffffUL)
686 static int nfs_lock_check_bounds(const struct file_lock *fl)
687 {
688 	__s32 start, end;
689 
690 	start = (__s32)fl->fl_start;
691 	if ((loff_t)start != fl->fl_start)
692 		goto out_einval;
693 
694 	if (fl->fl_end != OFFSET_MAX) {
695 		end = (__s32)fl->fl_end;
696 		if ((loff_t)end != fl->fl_end)
697 			goto out_einval;
698 	} else
699 		end = NFS_LOCK32_OFFSET_MAX;
700 
701 	if (start < 0 || start > end)
702 		goto out_einval;
703 	return 0;
704 out_einval:
705 	return -EINVAL;
706 }
707 
708 const struct nfs_rpc_ops nfs_v2_clientops = {
709 	.version	= 2,		       /* protocol version */
710 	.dentry_ops	= &nfs_dentry_operations,
711 	.dir_inode_ops	= &nfs_dir_inode_operations,
712 	.file_inode_ops	= &nfs_file_inode_operations,
713 	.getroot	= nfs_proc_get_root,
714 	.getattr	= nfs_proc_getattr,
715 	.setattr	= nfs_proc_setattr,
716 	.lookup		= nfs_proc_lookup,
717 	.access		= NULL,		       /* access */
718 	.readlink	= nfs_proc_readlink,
719 	.create		= nfs_proc_create,
720 	.remove		= nfs_proc_remove,
721 	.unlink_setup	= nfs_proc_unlink_setup,
722 	.unlink_done	= nfs_proc_unlink_done,
723 	.rename		= nfs_proc_rename,
724 	.rename_setup	= nfs_proc_rename_setup,
725 	.rename_done	= nfs_proc_rename_done,
726 	.link		= nfs_proc_link,
727 	.symlink	= nfs_proc_symlink,
728 	.mkdir		= nfs_proc_mkdir,
729 	.rmdir		= nfs_proc_rmdir,
730 	.readdir	= nfs_proc_readdir,
731 	.mknod		= nfs_proc_mknod,
732 	.statfs		= nfs_proc_statfs,
733 	.fsinfo		= nfs_proc_fsinfo,
734 	.pathconf	= nfs_proc_pathconf,
735 	.decode_dirent	= nfs2_decode_dirent,
736 	.read_setup	= nfs_proc_read_setup,
737 	.read_done	= nfs_read_done,
738 	.write_setup	= nfs_proc_write_setup,
739 	.write_done	= nfs_write_done,
740 	.commit_setup	= nfs_proc_commit_setup,
741 	.lock		= nfs_proc_lock,
742 	.lock_check_bounds = nfs_lock_check_bounds,
743 	.close_context	= nfs_close_context,
744 };
745