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NFS: Optimise inode attribute cache updates
[linux-2.6-block.git] / fs / nfs / proc.c
CommitLineData
1da177e4
LT		 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/slab.h>
33#include <linux/time.h>
34#include <linux/mm.h>
35#include <linux/utsname.h>
36#include <linux/errno.h>
37#include <linux/string.h>
38#include <linux/in.h>
39#include <linux/pagemap.h>
40#include <linux/sunrpc/clnt.h>
41#include <linux/nfs.h>
42#include <linux/nfs2.h>
43#include <linux/nfs_fs.h>
44#include <linux/nfs_page.h>
45#include <linux/lockd/bind.h>
46#include <linux/smp_lock.h>
47
48#define NFSDBG_FACILITY NFSDBG_PROC
49
50extern struct rpc_procinfo nfs_procedures[];
51
52/*
53 * Bare-bones access to getattr: this is for nfs_read_super.
54 */
55static int
56nfs_proc_get_root(struct nfs_server *server, struct nfs_fh *fhandle,
57 struct nfs_fsinfo *info)
58{
59 struct nfs_fattr *fattr = info->fattr;
60 struct nfs2_fsstat fsinfo;
61 int status;
62
63 dprintk("%s: call getattr\n", __FUNCTION__);
0e574af1 64 nfs_fattr_init(fattr);
1da177e4
LT		 65 status = rpc_call(server->client_sys, NFSPROC_GETATTR, fhandle, fattr, 0);
66 dprintk("%s: reply getattr: %d\n", __FUNCTION__, status);
67 if (status)
68 return status;
69 dprintk("%s: call statfs\n", __FUNCTION__);
70 status = rpc_call(server->client_sys, NFSPROC_STATFS, fhandle, &fsinfo, 0);
71 dprintk("%s: reply statfs: %d\n", __FUNCTION__, status);
72 if (status)
73 return status;
74 info->rtmax = NFS_MAXDATA;
75 info->rtpref = fsinfo.tsize;
76 info->rtmult = fsinfo.bsize;
77 info->wtmax = NFS_MAXDATA;
78 info->wtpref = fsinfo.tsize;
79 info->wtmult = fsinfo.bsize;
80 info->dtpref = fsinfo.tsize;
81 info->maxfilesize = 0x7FFFFFFF;
82 info->lease_time = 0;
83 return 0;
84}
85
86/*
87 * One function for each procedure in the NFS protocol.
88 */
89static int
90nfs_proc_getattr(struct nfs_server *server, struct nfs_fh *fhandle,
91 struct nfs_fattr *fattr)
92{
93 int status;
94
95 dprintk("NFS call getattr\n");
0e574af1 96 nfs_fattr_init(fattr);
1da177e4
LT		 97 status = rpc_call(server->client, NFSPROC_GETATTR,
98 fhandle, fattr, 0);
99 dprintk("NFS reply getattr: %d\n", status);
100 return status;
101}
102
103static int
104nfs_proc_setattr(struct dentry *dentry, struct nfs_fattr *fattr,
105 struct iattr *sattr)
106{
107 struct inode *inode = dentry->d_inode;
108 struct nfs_sattrargs arg = {
109 .fh = NFS_FH(inode),
110 .sattr = sattr
111 };
112 int status;
113
114 dprintk("NFS call setattr\n");
0e574af1 115 nfs_fattr_init(fattr);
1da177e4 116 status = rpc_call(NFS_CLIENT(inode), NFSPROC_SETATTR, &arg, fattr, 0);
65e4308d
TM		 117 if (status == 0)
118 nfs_setattr_update_inode(inode, sattr);
1da177e4
LT		 119 dprintk("NFS reply setattr: %d\n", status);
120 return status;
121}
122
123static int
124nfs_proc_lookup(struct inode *dir, struct qstr *name,
125 struct nfs_fh *fhandle, struct nfs_fattr *fattr)
126{
127 struct nfs_diropargs arg = {
128 .fh = NFS_FH(dir),
129 .name = name->name,
130 .len = name->len
131 };
132 struct nfs_diropok res = {
133 .fh = fhandle,
134 .fattr = fattr
135 };
136 int status;
137
138 dprintk("NFS call lookup %s\n", name->name);
0e574af1 139 nfs_fattr_init(fattr);
1da177e4
LT		 140 status = rpc_call(NFS_CLIENT(dir), NFSPROC_LOOKUP, &arg, &res, 0);
141 dprintk("NFS reply lookup: %d\n", status);
142 return status;
143}
144
145static int nfs_proc_readlink(struct inode *inode, struct page *page,
146 unsigned int pgbase, unsigned int pglen)
147{
148 struct nfs_readlinkargs args = {
149 .fh = NFS_FH(inode),
150 .pgbase = pgbase,
151 .pglen = pglen,
152 .pages = &page
153 };
154 int status;
155
156 dprintk("NFS call readlink\n");
157 status = rpc_call(NFS_CLIENT(inode), NFSPROC_READLINK, &args, NULL, 0);
158 dprintk("NFS reply readlink: %d\n", status);
159 return status;
160}
161
162static int nfs_proc_read(struct nfs_read_data *rdata)
163{
164 int flags = rdata->flags;
165 struct inode * inode = rdata->inode;
166 struct nfs_fattr * fattr = rdata->res.fattr;
167 struct rpc_message msg = {
168 .rpc_proc = &nfs_procedures[NFSPROC_READ],
169 .rpc_argp = &rdata->args,
170 .rpc_resp = &rdata->res,
171 .rpc_cred = rdata->cred,
172 };
173 int status;
174
175 dprintk("NFS call read %d @ %Ld\n", rdata->args.count,
176 (long long) rdata->args.offset);
0e574af1 177 nfs_fattr_init(fattr);
1da177e4
LT		 178 status = rpc_call_sync(NFS_CLIENT(inode), &msg, flags);
179 if (status >= 0) {
180 nfs_refresh_inode(inode, fattr);
181 /* Emulate the eof flag, which isn't normally needed in NFSv2
182 * as it is guaranteed to always return the file attributes
183 */
184 if (rdata->args.offset + rdata->args.count >= fattr->size)
185 rdata->res.eof = 1;
186 }
187 dprintk("NFS reply read: %d\n", status);
188 return status;
189}
190
191static int nfs_proc_write(struct nfs_write_data *wdata)
192{
193 int flags = wdata->flags;
194 struct inode * inode = wdata->inode;
195 struct nfs_fattr * fattr = wdata->res.fattr;
196 struct rpc_message msg = {
197 .rpc_proc = &nfs_procedures[NFSPROC_WRITE],
198 .rpc_argp = &wdata->args,
199 .rpc_resp = &wdata->res,
200 .rpc_cred = wdata->cred,
201 };
202 int status;
203
204 dprintk("NFS call write %d @ %Ld\n", wdata->args.count,
205 (long long) wdata->args.offset);
0e574af1 206 nfs_fattr_init(fattr);
1da177e4
LT		 207 status = rpc_call_sync(NFS_CLIENT(inode), &msg, flags);
208 if (status >= 0) {
209 nfs_refresh_inode(inode, fattr);
210 wdata->res.count = wdata->args.count;
211 wdata->verf.committed = NFS_FILE_SYNC;
212 }
213 dprintk("NFS reply write: %d\n", status);
214 return status < 0? status : wdata->res.count;
215}
216
217static int
218nfs_proc_create(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
02a913a7 219 int flags, struct nameidata *nd)
1da177e4
LT		 220{
221 struct nfs_fh fhandle;
222 struct nfs_fattr fattr;
223 struct nfs_createargs arg = {
224 .fh = NFS_FH(dir),
225 .name = dentry->d_name.name,
226 .len = dentry->d_name.len,
227 .sattr = sattr
228 };
229 struct nfs_diropok res = {
230 .fh = &fhandle,
231 .fattr = &fattr
232 };
233 int status;
234
0e574af1 235 nfs_fattr_init(&fattr);
1da177e4
LT		 236 dprintk("NFS call create %s\n", dentry->d_name.name);
237 status = rpc_call(NFS_CLIENT(dir), NFSPROC_CREATE, &arg, &res, 0);
238 if (status == 0)
239 status = nfs_instantiate(dentry, &fhandle, &fattr);
240 dprintk("NFS reply create: %d\n", status);
241 return status;
242}
243
244/*
245 * In NFSv2, mknod is grafted onto the create call.
246 */
247static int
248nfs_proc_mknod(struct inode *dir, struct dentry *dentry, struct iattr *sattr,
249 dev_t rdev)
250{
251 struct nfs_fh fhandle;
252 struct nfs_fattr fattr;
253 struct nfs_createargs arg = {
254 .fh = NFS_FH(dir),
255 .name = dentry->d_name.name,
256 .len = dentry->d_name.len,
257 .sattr = sattr
258 };
259 struct nfs_diropok res = {
260 .fh = &fhandle,
261 .fattr = &fattr
262 };
263 int status, mode;
264
265 dprintk("NFS call mknod %s\n", dentry->d_name.name);
266
267 mode = sattr->ia_mode;
268 if (S_ISFIFO(mode)) {
269 sattr->ia_mode = (mode & ~S_IFMT) | S_IFCHR;
270 sattr->ia_valid &= ~ATTR_SIZE;
271 } else if (S_ISCHR(mode) || S_ISBLK(mode)) {
272 sattr->ia_valid |= ATTR_SIZE;
273 sattr->ia_size = new_encode_dev(rdev);/* get out your barf bag */
274 }
275
0e574af1 276 nfs_fattr_init(&fattr);
1da177e4
LT		 277 status = rpc_call(NFS_CLIENT(dir), NFSPROC_CREATE, &arg, &res, 0);
278
279 if (status == -EINVAL && S_ISFIFO(mode)) {
280 sattr->ia_mode = mode;
0e574af1 281 nfs_fattr_init(&fattr);
1da177e4
LT		 282 status = rpc_call(NFS_CLIENT(dir), NFSPROC_CREATE, &arg, &res, 0);
283 }
284 if (status == 0)
285 status = nfs_instantiate(dentry, &fhandle, &fattr);
286 dprintk("NFS reply mknod: %d\n", status);
287 return status;
288}
289
290static int
291nfs_proc_remove(struct inode *dir, struct qstr *name)
292{
293 struct nfs_diropargs arg = {
294 .fh = NFS_FH(dir),
295 .name = name->name,
296 .len = name->len
297 };
298 struct rpc_message msg = {
299 .rpc_proc = &nfs_procedures[NFSPROC_REMOVE],
300 .rpc_argp = &arg,
301 .rpc_resp = NULL,
302 .rpc_cred = NULL
303 };
304 int status;
305
306 dprintk("NFS call remove %s\n", name->name);
307 status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
308
309 dprintk("NFS reply remove: %d\n", status);
310 return status;
311}
312
313static int
314nfs_proc_unlink_setup(struct rpc_message *msg, struct dentry *dir, struct qstr *name)
315{
316 struct nfs_diropargs *arg;
317
318 arg = (struct nfs_diropargs *)kmalloc(sizeof(*arg), GFP_KERNEL);
319 if (!arg)
320 return -ENOMEM;
321 arg->fh = NFS_FH(dir->d_inode);
322 arg->name = name->name;
323 arg->len = name->len;
324 msg->rpc_proc = &nfs_procedures[NFSPROC_REMOVE];
325 msg->rpc_argp = arg;
326 return 0;
327}
328
329static int
330nfs_proc_unlink_done(struct dentry *dir, struct rpc_task *task)
331{
332 struct rpc_message *msg = &task->tk_msg;
333
334 if (msg->rpc_argp)
335 kfree(msg->rpc_argp);
336 return 0;
337}
338
339static int
340nfs_proc_rename(struct inode *old_dir, struct qstr *old_name,
341 struct inode *new_dir, struct qstr *new_name)
342{
343 struct nfs_renameargs arg = {
344 .fromfh = NFS_FH(old_dir),
345 .fromname = old_name->name,
346 .fromlen = old_name->len,
347 .tofh = NFS_FH(new_dir),
348 .toname = new_name->name,
349 .tolen = new_name->len
350 };
351 int status;
352
353 dprintk("NFS call rename %s -> %s\n", old_name->name, new_name->name);
354 status = rpc_call(NFS_CLIENT(old_dir), NFSPROC_RENAME, &arg, NULL, 0);
355 dprintk("NFS reply rename: %d\n", status);
356 return status;
357}
358
359static int
360nfs_proc_link(struct inode *inode, struct inode *dir, struct qstr *name)
361{
362 struct nfs_linkargs arg = {
363 .fromfh = NFS_FH(inode),
364 .tofh = NFS_FH(dir),
365 .toname = name->name,
366 .tolen = name->len
367 };
368 int status;
369
370 dprintk("NFS call link %s\n", name->name);
371 status = rpc_call(NFS_CLIENT(inode), NFSPROC_LINK, &arg, NULL, 0);
372 dprintk("NFS reply link: %d\n", status);
373 return status;
374}
375
376static int
377nfs_proc_symlink(struct inode *dir, struct qstr *name, struct qstr *path,
378 struct iattr *sattr, struct nfs_fh *fhandle,
379 struct nfs_fattr *fattr)
380{
381 struct nfs_symlinkargs arg = {
382 .fromfh = NFS_FH(dir),
383 .fromname = name->name,
384 .fromlen = name->len,
385 .topath = path->name,
386 .tolen = path->len,
387 .sattr = sattr
388 };
389 int status;
390
391 if (path->len > NFS2_MAXPATHLEN)
392 return -ENAMETOOLONG;
393 dprintk("NFS call symlink %s -> %s\n", name->name, path->name);
0e574af1 394 nfs_fattr_init(fattr);
1da177e4
LT		 395 fhandle->size = 0;
396 status = rpc_call(NFS_CLIENT(dir), NFSPROC_SYMLINK, &arg, NULL, 0);
397 dprintk("NFS reply symlink: %d\n", status);
398 return status;
399}
400
401static int
402nfs_proc_mkdir(struct inode *dir, struct dentry *dentry, struct iattr *sattr)
403{
404 struct nfs_fh fhandle;
405 struct nfs_fattr fattr;
406 struct nfs_createargs arg = {
407 .fh = NFS_FH(dir),
408 .name = dentry->d_name.name,
409 .len = dentry->d_name.len,
410 .sattr = sattr
411 };
412 struct nfs_diropok res = {
413 .fh = &fhandle,
414 .fattr = &fattr
415 };
416 int status;
417
418 dprintk("NFS call mkdir %s\n", dentry->d_name.name);
0e574af1 419 nfs_fattr_init(&fattr);
1da177e4
LT		 420 status = rpc_call(NFS_CLIENT(dir), NFSPROC_MKDIR, &arg, &res, 0);
421 if (status == 0)
422 status = nfs_instantiate(dentry, &fhandle, &fattr);
423 dprintk("NFS reply mkdir: %d\n", status);
424 return status;
425}
426
427static int
428nfs_proc_rmdir(struct inode *dir, struct qstr *name)
429{
430 struct nfs_diropargs arg = {
431 .fh = NFS_FH(dir),
432 .name = name->name,
433 .len = name->len
434 };
435 int status;
436
437 dprintk("NFS call rmdir %s\n", name->name);
438 status = rpc_call(NFS_CLIENT(dir), NFSPROC_RMDIR, &arg, NULL, 0);
439 dprintk("NFS reply rmdir: %d\n", status);
440 return status;
441}
442
443/*
444 * The READDIR implementation is somewhat hackish - we pass a temporary
445 * buffer to the encode function, which installs it in the receive
446 * the receive iovec. The decode function just parses the reply to make
447 * sure it is syntactically correct; the entries itself are decoded
448 * from nfs_readdir by calling the decode_entry function directly.
449 */
450static int
451nfs_proc_readdir(struct dentry *dentry, struct rpc_cred *cred,
452 u64 cookie, struct page *page, unsigned int count, int plus)
453{
454 struct inode *dir = dentry->d_inode;
455 struct nfs_readdirargs arg = {
456 .fh = NFS_FH(dir),
457 .cookie = cookie,
458 .count = count,
459 .pages = &page
460 };
461 struct rpc_message msg = {
462 .rpc_proc = &nfs_procedures[NFSPROC_READDIR],
463 .rpc_argp = &arg,
464 .rpc_resp = NULL,
465 .rpc_cred = cred
466 };
467 int status;
468
469 lock_kernel();
470
471 dprintk("NFS call readdir %d\n", (unsigned int)cookie);
472 status = rpc_call_sync(NFS_CLIENT(dir), &msg, 0);
473
474 dprintk("NFS reply readdir: %d\n", status);
475 unlock_kernel();
476 return status;
477}
478
479static int
480nfs_proc_statfs(struct nfs_server *server, struct nfs_fh *fhandle,
481 struct nfs_fsstat *stat)
482{
483 struct nfs2_fsstat fsinfo;
484 int status;
485
486 dprintk("NFS call statfs\n");
0e574af1 487 nfs_fattr_init(stat->fattr);
1da177e4
LT		 488 status = rpc_call(server->client, NFSPROC_STATFS, fhandle, &fsinfo, 0);
489 dprintk("NFS reply statfs: %d\n", status);
490 if (status)
491 goto out;
492 stat->tbytes = (u64)fsinfo.blocks * fsinfo.bsize;
493 stat->fbytes = (u64)fsinfo.bfree * fsinfo.bsize;
494 stat->abytes = (u64)fsinfo.bavail * fsinfo.bsize;
495 stat->tfiles = 0;
496 stat->ffiles = 0;
497 stat->afiles = 0;
498out:
499 return status;
500}
501
502static int
503nfs_proc_fsinfo(struct nfs_server *server, struct nfs_fh *fhandle,
504 struct nfs_fsinfo *info)
505{
506 struct nfs2_fsstat fsinfo;
507 int status;
508
509 dprintk("NFS call fsinfo\n");
0e574af1 510 nfs_fattr_init(info->fattr);
1da177e4
LT		 511 status = rpc_call(server->client, NFSPROC_STATFS, fhandle, &fsinfo, 0);
512 dprintk("NFS reply fsinfo: %d\n", status);
513 if (status)
514 goto out;
515 info->rtmax = NFS_MAXDATA;
516 info->rtpref = fsinfo.tsize;
517 info->rtmult = fsinfo.bsize;
518 info->wtmax = NFS_MAXDATA;
519 info->wtpref = fsinfo.tsize;
520 info->wtmult = fsinfo.bsize;
521 info->dtpref = fsinfo.tsize;
522 info->maxfilesize = 0x7FFFFFFF;
523 info->lease_time = 0;
524out:
525 return status;
526}
527
528static int
529nfs_proc_pathconf(struct nfs_server *server, struct nfs_fh *fhandle,
530 struct nfs_pathconf *info)
531{
532 info->max_link = 0;
533 info->max_namelen = NFS2_MAXNAMLEN;
534 return 0;
535}
536
537extern u32 * nfs_decode_dirent(u32 *, struct nfs_entry *, int);
538
539static void
540nfs_read_done(struct rpc_task *task)
541{
542 struct nfs_read_data *data = (struct nfs_read_data *) task->tk_calldata;
543
544 if (task->tk_status >= 0) {
545 nfs_refresh_inode(data->inode, data->res.fattr);
546 /* Emulate the eof flag, which isn't normally needed in NFSv2
547 * as it is guaranteed to always return the file attributes
548 */
549 if (data->args.offset + data->args.count >= data->res.fattr->size)
550 data->res.eof = 1;
551 }
552 nfs_readpage_result(task);
553}
554
555static void
556nfs_proc_read_setup(struct nfs_read_data *data)
557{
558 struct rpc_task *task = &data->task;
559 struct inode *inode = data->inode;
560 int flags;
561 struct rpc_message msg = {
562 .rpc_proc = &nfs_procedures[NFSPROC_READ],
563 .rpc_argp = &data->args,
564 .rpc_resp = &data->res,
565 .rpc_cred = data->cred,
566 };
567
568 /* N.B. Do we need to test? Never called for swapfile inode */
569 flags = RPC_TASK_ASYNC | (IS_SWAPFILE(inode)? NFS_RPC_SWAPFLAGS : 0);
570
571 /* Finalize the task. */
572 rpc_init_task(task, NFS_CLIENT(inode), nfs_read_done, flags);
573 rpc_call_setup(task, &msg, 0);
574}
575
576static void
577nfs_write_done(struct rpc_task *task)
578{
579 struct nfs_write_data *data = (struct nfs_write_data *) task->tk_calldata;
580
581 if (task->tk_status >= 0)
582 nfs_refresh_inode(data->inode, data->res.fattr);
583 nfs_writeback_done(task);
584}
585
586static void
587nfs_proc_write_setup(struct nfs_write_data *data, int how)
588{
589 struct rpc_task *task = &data->task;
590 struct inode *inode = data->inode;
591 int flags;
592 struct rpc_message msg = {
593 .rpc_proc = &nfs_procedures[NFSPROC_WRITE],
594 .rpc_argp = &data->args,
595 .rpc_resp = &data->res,
596 .rpc_cred = data->cred,
597 };
598
599 /* Note: NFSv2 ignores @stable and always uses NFS_FILE_SYNC */
600 data->args.stable = NFS_FILE_SYNC;
601
602 /* Set the initial flags for the task. */
603 flags = (how & FLUSH_SYNC) ? 0 : RPC_TASK_ASYNC;
604
605 /* Finalize the task. */
606 rpc_init_task(task, NFS_CLIENT(inode), nfs_write_done, flags);
607 rpc_call_setup(task, &msg, 0);
608}
609
610static void
611nfs_proc_commit_setup(struct nfs_write_data *data, int how)
612{
613 BUG();
614}
615
616static int
617nfs_proc_lock(struct file *filp, int cmd, struct file_lock *fl)
618{
619 return nlmclnt_proc(filp->f_dentry->d_inode, cmd, fl);
620}
621
622
623struct nfs_rpc_ops nfs_v2_clientops = {
624 .version = 2, /* protocol version */
625 .dentry_ops = &nfs_dentry_operations,
626 .dir_inode_ops = &nfs_dir_inode_operations,
92cfc62c 627 .file_inode_ops = &nfs_file_inode_operations,
1da177e4
LT		 628 .getroot = nfs_proc_get_root,
629 .getattr = nfs_proc_getattr,
630 .setattr = nfs_proc_setattr,
631 .lookup = nfs_proc_lookup,
632 .access = NULL, /* access */
633 .readlink = nfs_proc_readlink,
634 .read = nfs_proc_read,
635 .write = nfs_proc_write,
636 .commit = NULL, /* commit */
637 .create = nfs_proc_create,
638 .remove = nfs_proc_remove,
639 .unlink_setup = nfs_proc_unlink_setup,
640 .unlink_done = nfs_proc_unlink_done,
641 .rename = nfs_proc_rename,
642 .link = nfs_proc_link,
643 .symlink = nfs_proc_symlink,
644 .mkdir = nfs_proc_mkdir,
645 .rmdir = nfs_proc_rmdir,
646 .readdir = nfs_proc_readdir,
647 .mknod = nfs_proc_mknod,
648 .statfs = nfs_proc_statfs,
649 .fsinfo = nfs_proc_fsinfo,
650 .pathconf = nfs_proc_pathconf,
651 .decode_dirent = nfs_decode_dirent,
652 .read_setup = nfs_proc_read_setup,
653 .write_setup = nfs_proc_write_setup,
654 .commit_setup = nfs_proc_commit_setup,
655 .file_open = nfs_open,
656 .file_release = nfs_release,
657 .lock = nfs_proc_lock,
658};
Linux 6.x block layer and io_uring tree(s)