nfs_open_context doesn't need struct path either
[GitHub/mt8127/android_kernel_alcatel_ttab.git] / fs / nfs / dir.c
CommitLineData
1da177e4
LT
1/*
2 * linux/fs/nfs/dir.c
3 *
4 * Copyright (C) 1992 Rick Sladkey
5 *
6 * nfs directory handling functions
7 *
8 * 10 Apr 1996 Added silly rename for unlink --okir
9 * 28 Sep 1996 Improved directory cache --okir
10 * 23 Aug 1997 Claus Heine claus@momo.math.rwth-aachen.de
11 * Re-implemented silly rename for unlink, newly implemented
12 * silly rename for nfs_rename() following the suggestions
13 * of Olaf Kirch (okir) found in this file.
14 * Following Linus comments on my original hack, this version
15 * depends only on the dcache stuff and doesn't touch the inode
16 * layer (iput() and friends).
17 * 6 Jun 1999 Cache readdir lookups in the page cache. -DaveM
18 */
19
20#include <linux/time.h>
21#include <linux/errno.h>
22#include <linux/stat.h>
23#include <linux/fcntl.h>
24#include <linux/string.h>
25#include <linux/kernel.h>
26#include <linux/slab.h>
27#include <linux/mm.h>
28#include <linux/sunrpc/clnt.h>
29#include <linux/nfs_fs.h>
30#include <linux/nfs_mount.h>
31#include <linux/pagemap.h>
873101b3 32#include <linux/pagevec.h>
1da177e4 33#include <linux/namei.h>
54ceac45 34#include <linux/mount.h>
e8edc6e0 35#include <linux/sched.h>
04e4bd1c 36#include <linux/kmemleak.h>
64c2ce8b 37#include <linux/xattr.h>
1da177e4
LT
38
39#include "delegation.h"
91d5b470 40#include "iostat.h"
4c30d56e 41#include "internal.h"
cd9a1c0e 42#include "fscache.h"
1da177e4 43
1da177e4
LT
44/* #define NFS_DEBUG_VERBOSE 1 */
45
46static int nfs_opendir(struct inode *, struct file *);
480c2006 47static int nfs_closedir(struct inode *, struct file *);
1da177e4
LT
48static int nfs_readdir(struct file *, void *, filldir_t);
49static struct dentry *nfs_lookup(struct inode *, struct dentry *, struct nameidata *);
50static int nfs_create(struct inode *, struct dentry *, int, struct nameidata *);
51static int nfs_mkdir(struct inode *, struct dentry *, int);
52static int nfs_rmdir(struct inode *, struct dentry *);
53static int nfs_unlink(struct inode *, struct dentry *);
54static int nfs_symlink(struct inode *, struct dentry *, const char *);
55static int nfs_link(struct dentry *, struct inode *, struct dentry *);
56static int nfs_mknod(struct inode *, struct dentry *, int, dev_t);
57static int nfs_rename(struct inode *, struct dentry *,
58 struct inode *, struct dentry *);
7ea80859 59static int nfs_fsync_dir(struct file *, int);
f0dd2136 60static loff_t nfs_llseek_dir(struct file *, loff_t, int);
11de3b11 61static void nfs_readdir_clear_array(struct page*);
1da177e4 62
4b6f5d20 63const struct file_operations nfs_dir_operations = {
f0dd2136 64 .llseek = nfs_llseek_dir,
1da177e4
LT
65 .read = generic_read_dir,
66 .readdir = nfs_readdir,
67 .open = nfs_opendir,
480c2006 68 .release = nfs_closedir,
1da177e4
LT
69 .fsync = nfs_fsync_dir,
70};
71
92e1d5be 72const struct inode_operations nfs_dir_inode_operations = {
1da177e4
LT
73 .create = nfs_create,
74 .lookup = nfs_lookup,
75 .link = nfs_link,
76 .unlink = nfs_unlink,
77 .symlink = nfs_symlink,
78 .mkdir = nfs_mkdir,
79 .rmdir = nfs_rmdir,
80 .mknod = nfs_mknod,
81 .rename = nfs_rename,
82 .permission = nfs_permission,
83 .getattr = nfs_getattr,
84 .setattr = nfs_setattr,
85};
86
11de3b11
TM
87const struct address_space_operations nfs_dir_aops = {
88 .freepage = nfs_readdir_clear_array,
d1bacf9e
BS
89};
90
b7fa0554 91#ifdef CONFIG_NFS_V3
92e1d5be 92const struct inode_operations nfs3_dir_inode_operations = {
b7fa0554
AG
93 .create = nfs_create,
94 .lookup = nfs_lookup,
95 .link = nfs_link,
96 .unlink = nfs_unlink,
97 .symlink = nfs_symlink,
98 .mkdir = nfs_mkdir,
99 .rmdir = nfs_rmdir,
100 .mknod = nfs_mknod,
101 .rename = nfs_rename,
102 .permission = nfs_permission,
103 .getattr = nfs_getattr,
104 .setattr = nfs_setattr,
105 .listxattr = nfs3_listxattr,
106 .getxattr = nfs3_getxattr,
107 .setxattr = nfs3_setxattr,
108 .removexattr = nfs3_removexattr,
109};
110#endif /* CONFIG_NFS_V3 */
111
1da177e4
LT
112#ifdef CONFIG_NFS_V4
113
114static struct dentry *nfs_atomic_lookup(struct inode *, struct dentry *, struct nameidata *);
c0204fd2 115static int nfs_open_create(struct inode *dir, struct dentry *dentry, int mode, struct nameidata *nd);
92e1d5be 116const struct inode_operations nfs4_dir_inode_operations = {
c0204fd2 117 .create = nfs_open_create,
1da177e4
LT
118 .lookup = nfs_atomic_lookup,
119 .link = nfs_link,
120 .unlink = nfs_unlink,
121 .symlink = nfs_symlink,
122 .mkdir = nfs_mkdir,
123 .rmdir = nfs_rmdir,
124 .mknod = nfs_mknod,
125 .rename = nfs_rename,
126 .permission = nfs_permission,
127 .getattr = nfs_getattr,
128 .setattr = nfs_setattr,
64c2ce8b
AK
129 .getxattr = generic_getxattr,
130 .setxattr = generic_setxattr,
131 .listxattr = generic_listxattr,
132 .removexattr = generic_removexattr,
1da177e4
LT
133};
134
135#endif /* CONFIG_NFS_V4 */
136
480c2006
BS
137static struct nfs_open_dir_context *alloc_nfs_open_dir_context(struct rpc_cred *cred)
138{
139 struct nfs_open_dir_context *ctx;
140 ctx = kmalloc(sizeof(*ctx), GFP_KERNEL);
141 if (ctx != NULL) {
8ef2ce3e 142 ctx->duped = 0;
480c2006 143 ctx->dir_cookie = 0;
8ef2ce3e 144 ctx->dup_cookie = 0;
480c2006
BS
145 ctx->cred = get_rpccred(cred);
146 } else
147 ctx = ERR_PTR(-ENOMEM);
148 return ctx;
149}
150
151static void put_nfs_open_dir_context(struct nfs_open_dir_context *ctx)
152{
153 put_rpccred(ctx->cred);
154 kfree(ctx);
155}
156
1da177e4
LT
157/*
158 * Open file
159 */
160static int
161nfs_opendir(struct inode *inode, struct file *filp)
162{
480c2006
BS
163 int res = 0;
164 struct nfs_open_dir_context *ctx;
165 struct rpc_cred *cred;
1da177e4 166
6da24bc9 167 dfprintk(FILE, "NFS: open dir(%s/%s)\n",
cc0dd2d1
CL
168 filp->f_path.dentry->d_parent->d_name.name,
169 filp->f_path.dentry->d_name.name);
170
171 nfs_inc_stats(inode, NFSIOS_VFSOPEN);
1e7cb3dc 172
480c2006
BS
173 cred = rpc_lookup_cred();
174 if (IS_ERR(cred))
175 return PTR_ERR(cred);
176 ctx = alloc_nfs_open_dir_context(cred);
177 if (IS_ERR(ctx)) {
178 res = PTR_ERR(ctx);
179 goto out;
180 }
181 filp->private_data = ctx;
f5a73672
NB
182 if (filp->f_path.dentry == filp->f_path.mnt->mnt_root) {
183 /* This is a mountpoint, so d_revalidate will never
184 * have been called, so we need to refresh the
185 * inode (for close-open consistency) ourselves.
186 */
187 __nfs_revalidate_inode(NFS_SERVER(inode), inode);
188 }
480c2006
BS
189out:
190 put_rpccred(cred);
1da177e4
LT
191 return res;
192}
193
480c2006
BS
194static int
195nfs_closedir(struct inode *inode, struct file *filp)
196{
197 put_nfs_open_dir_context(filp->private_data);
198 return 0;
199}
200
d1bacf9e
BS
201struct nfs_cache_array_entry {
202 u64 cookie;
203 u64 ino;
204 struct qstr string;
0b26a0bf 205 unsigned char d_type;
d1bacf9e
BS
206};
207
208struct nfs_cache_array {
209 unsigned int size;
210 int eof_index;
211 u64 last_cookie;
212 struct nfs_cache_array_entry array[0];
213};
214
573c4e1e 215typedef int (*decode_dirent_t)(struct xdr_stream *, struct nfs_entry *, int);
1da177e4
LT
216typedef struct {
217 struct file *file;
218 struct page *page;
219 unsigned long page_index;
f0dd2136 220 u64 *dir_cookie;
0aded708 221 u64 last_cookie;
f0dd2136 222 loff_t current_index;
1da177e4 223 decode_dirent_t decode;
d1bacf9e 224
1f4eab7e 225 unsigned long timestamp;
4704f0e2 226 unsigned long gencount;
d1bacf9e
BS
227 unsigned int cache_entry_index;
228 unsigned int plus:1;
229 unsigned int eof:1;
1da177e4
LT
230} nfs_readdir_descriptor_t;
231
d1bacf9e
BS
232/*
233 * The caller is responsible for calling nfs_readdir_release_array(page)
1da177e4
LT
234 */
235static
d1bacf9e
BS
236struct nfs_cache_array *nfs_readdir_get_array(struct page *page)
237{
8cd51a0c 238 void *ptr;
d1bacf9e
BS
239 if (page == NULL)
240 return ERR_PTR(-EIO);
8cd51a0c
TM
241 ptr = kmap(page);
242 if (ptr == NULL)
243 return ERR_PTR(-ENOMEM);
244 return ptr;
d1bacf9e
BS
245}
246
247static
248void nfs_readdir_release_array(struct page *page)
249{
250 kunmap(page);
251}
252
253/*
254 * we are freeing strings created by nfs_add_to_readdir_array()
255 */
256static
11de3b11 257void nfs_readdir_clear_array(struct page *page)
d1bacf9e 258{
11de3b11 259 struct nfs_cache_array *array;
d1bacf9e 260 int i;
8cd51a0c 261
11de3b11 262 array = kmap_atomic(page, KM_USER0);
d1bacf9e
BS
263 for (i = 0; i < array->size; i++)
264 kfree(array->array[i].string.name);
11de3b11 265 kunmap_atomic(array, KM_USER0);
d1bacf9e
BS
266}
267
268/*
269 * the caller is responsible for freeing qstr.name
270 * when called by nfs_readdir_add_to_array, the strings will be freed in
271 * nfs_clear_readdir_array()
272 */
273static
4a201d6e 274int nfs_readdir_make_qstr(struct qstr *string, const char *name, unsigned int len)
d1bacf9e
BS
275{
276 string->len = len;
277 string->name = kmemdup(name, len, GFP_KERNEL);
4a201d6e
TM
278 if (string->name == NULL)
279 return -ENOMEM;
04e4bd1c
CM
280 /*
281 * Avoid a kmemleak false positive. The pointer to the name is stored
282 * in a page cache page which kmemleak does not scan.
283 */
284 kmemleak_not_leak(string->name);
4a201d6e
TM
285 string->hash = full_name_hash(name, len);
286 return 0;
d1bacf9e
BS
287}
288
289static
290int nfs_readdir_add_to_array(struct nfs_entry *entry, struct page *page)
291{
292 struct nfs_cache_array *array = nfs_readdir_get_array(page);
4a201d6e
TM
293 struct nfs_cache_array_entry *cache_entry;
294 int ret;
295
d1bacf9e
BS
296 if (IS_ERR(array))
297 return PTR_ERR(array);
3020093f
TM
298
299 cache_entry = &array->array[array->size];
300
301 /* Check that this entry lies within the page bounds */
8cd51a0c 302 ret = -ENOSPC;
3020093f 303 if ((char *)&cache_entry[1] - (char *)page_address(page) > PAGE_SIZE)
4a201d6e 304 goto out;
d1bacf9e 305
4a201d6e
TM
306 cache_entry->cookie = entry->prev_cookie;
307 cache_entry->ino = entry->ino;
0b26a0bf 308 cache_entry->d_type = entry->d_type;
4a201d6e
TM
309 ret = nfs_readdir_make_qstr(&cache_entry->string, entry->name, entry->len);
310 if (ret)
311 goto out;
d1bacf9e 312 array->last_cookie = entry->cookie;
8cd51a0c 313 array->size++;
47c716cb 314 if (entry->eof != 0)
d1bacf9e 315 array->eof_index = array->size;
4a201d6e 316out:
d1bacf9e 317 nfs_readdir_release_array(page);
4a201d6e 318 return ret;
d1bacf9e
BS
319}
320
321static
322int nfs_readdir_search_for_pos(struct nfs_cache_array *array, nfs_readdir_descriptor_t *desc)
323{
324 loff_t diff = desc->file->f_pos - desc->current_index;
325 unsigned int index;
8ef2ce3e 326 struct nfs_open_dir_context *ctx = desc->file->private_data;
d1bacf9e
BS
327
328 if (diff < 0)
329 goto out_eof;
330 if (diff >= array->size) {
8cd51a0c 331 if (array->eof_index >= 0)
d1bacf9e 332 goto out_eof;
d1bacf9e
BS
333 return -EAGAIN;
334 }
335
336 index = (unsigned int)diff;
337 *desc->dir_cookie = array->array[index].cookie;
338 desc->cache_entry_index = index;
8ef2ce3e 339 ctx->duped = 0;
d1bacf9e
BS
340 return 0;
341out_eof:
342 desc->eof = 1;
343 return -EBADCOOKIE;
344}
345
346static
347int nfs_readdir_search_for_cookie(struct nfs_cache_array *array, nfs_readdir_descriptor_t *desc)
348{
349 int i;
8ef2ce3e 350 loff_t new_pos;
d1bacf9e 351 int status = -EAGAIN;
8ef2ce3e 352 struct nfs_open_dir_context *ctx = desc->file->private_data;
d1bacf9e
BS
353
354 for (i = 0; i < array->size; i++) {
d1bacf9e 355 if (array->array[i].cookie == *desc->dir_cookie) {
8ef2ce3e
BS
356 new_pos = desc->current_index + i;
357 if (new_pos < desc->file->f_pos) {
358 ctx->dup_cookie = *desc->dir_cookie;
359 ctx->duped = 1;
360 }
361 desc->file->f_pos = new_pos;
d1bacf9e 362 desc->cache_entry_index = i;
47c716cb 363 return 0;
d1bacf9e
BS
364 }
365 }
47c716cb 366 if (array->eof_index >= 0) {
8cd51a0c 367 status = -EBADCOOKIE;
18fb5fe4
TM
368 if (*desc->dir_cookie == array->last_cookie)
369 desc->eof = 1;
8cd51a0c 370 }
d1bacf9e
BS
371 return status;
372}
373
374static
375int nfs_readdir_search_array(nfs_readdir_descriptor_t *desc)
376{
377 struct nfs_cache_array *array;
47c716cb 378 int status;
d1bacf9e
BS
379
380 array = nfs_readdir_get_array(desc->page);
381 if (IS_ERR(array)) {
382 status = PTR_ERR(array);
383 goto out;
384 }
385
386 if (*desc->dir_cookie == 0)
387 status = nfs_readdir_search_for_pos(array, desc);
388 else
389 status = nfs_readdir_search_for_cookie(array, desc);
390
47c716cb 391 if (status == -EAGAIN) {
0aded708 392 desc->last_cookie = array->last_cookie;
e47c085a 393 desc->current_index += array->size;
47c716cb
TM
394 desc->page_index++;
395 }
d1bacf9e
BS
396 nfs_readdir_release_array(desc->page);
397out:
398 return status;
399}
400
401/* Fill a page with xdr information before transferring to the cache page */
402static
56e4ebf8 403int nfs_readdir_xdr_filler(struct page **pages, nfs_readdir_descriptor_t *desc,
d1bacf9e 404 struct nfs_entry *entry, struct file *file, struct inode *inode)
1da177e4 405{
480c2006
BS
406 struct nfs_open_dir_context *ctx = file->private_data;
407 struct rpc_cred *cred = ctx->cred;
4704f0e2 408 unsigned long timestamp, gencount;
1da177e4
LT
409 int error;
410
1da177e4
LT
411 again:
412 timestamp = jiffies;
4704f0e2 413 gencount = nfs_inc_attr_generation_counter();
56e4ebf8 414 error = NFS_PROTO(inode)->readdir(file->f_path.dentry, cred, entry->cookie, pages,
1da177e4
LT
415 NFS_SERVER(inode)->dtsize, desc->plus);
416 if (error < 0) {
417 /* We requested READDIRPLUS, but the server doesn't grok it */
418 if (error == -ENOTSUPP && desc->plus) {
419 NFS_SERVER(inode)->caps &= ~NFS_CAP_READDIRPLUS;
3a10c30a 420 clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
1da177e4
LT
421 desc->plus = 0;
422 goto again;
423 }
424 goto error;
425 }
1f4eab7e 426 desc->timestamp = timestamp;
4704f0e2 427 desc->gencount = gencount;
d1bacf9e
BS
428error:
429 return error;
1da177e4
LT
430}
431
573c4e1e
CL
432static int xdr_decode(nfs_readdir_descriptor_t *desc,
433 struct nfs_entry *entry, struct xdr_stream *xdr)
1da177e4 434{
573c4e1e 435 int error;
1da177e4 436
573c4e1e
CL
437 error = desc->decode(xdr, entry, desc->plus);
438 if (error)
439 return error;
d1bacf9e
BS
440 entry->fattr->time_start = desc->timestamp;
441 entry->fattr->gencount = desc->gencount;
442 return 0;
1da177e4
LT
443}
444
d39ab9de
BS
445static
446int nfs_same_file(struct dentry *dentry, struct nfs_entry *entry)
447{
d39ab9de
BS
448 if (dentry->d_inode == NULL)
449 goto different;
37a09f07 450 if (nfs_compare_fh(entry->fh, NFS_FH(dentry->d_inode)) != 0)
d39ab9de
BS
451 goto different;
452 return 1;
453different:
454 return 0;
455}
456
457static
458void nfs_prime_dcache(struct dentry *parent, struct nfs_entry *entry)
459{
4a201d6e
TM
460 struct qstr filename = {
461 .len = entry->len,
462 .name = entry->name,
463 };
464 struct dentry *dentry;
465 struct dentry *alias;
d39ab9de
BS
466 struct inode *dir = parent->d_inode;
467 struct inode *inode;
468
4a201d6e
TM
469 if (filename.name[0] == '.') {
470 if (filename.len == 1)
471 return;
472 if (filename.len == 2 && filename.name[1] == '.')
473 return;
474 }
475 filename.hash = full_name_hash(filename.name, filename.len);
d39ab9de 476
4a201d6e 477 dentry = d_lookup(parent, &filename);
d39ab9de
BS
478 if (dentry != NULL) {
479 if (nfs_same_file(dentry, entry)) {
480 nfs_refresh_inode(dentry->d_inode, entry->fattr);
481 goto out;
482 } else {
483 d_drop(dentry);
484 dput(dentry);
485 }
486 }
487
488 dentry = d_alloc(parent, &filename);
4a201d6e
TM
489 if (dentry == NULL)
490 return;
491
d39ab9de
BS
492 inode = nfs_fhget(dentry->d_sb, entry->fh, entry->fattr);
493 if (IS_ERR(inode))
494 goto out;
495
496 alias = d_materialise_unique(dentry, inode);
497 if (IS_ERR(alias))
498 goto out;
499 else if (alias) {
500 nfs_set_verifier(alias, nfs_save_change_attribute(dir));
501 dput(alias);
502 } else
503 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
504
505out:
506 dput(dentry);
d39ab9de
BS
507}
508
d1bacf9e
BS
509/* Perform conversion from xdr to cache array */
510static
8cd51a0c 511int nfs_readdir_page_filler(nfs_readdir_descriptor_t *desc, struct nfs_entry *entry,
6650239a 512 struct page **xdr_pages, struct page *page, unsigned int buflen)
1da177e4 513{
babddc72 514 struct xdr_stream stream;
f7da7a12 515 struct xdr_buf buf;
6650239a 516 struct page *scratch;
99424380 517 struct nfs_cache_array *array;
5c346854
TM
518 unsigned int count = 0;
519 int status;
babddc72 520
6650239a
TM
521 scratch = alloc_page(GFP_KERNEL);
522 if (scratch == NULL)
523 return -ENOMEM;
babddc72 524
f7da7a12 525 xdr_init_decode_pages(&stream, &buf, xdr_pages, buflen);
6650239a 526 xdr_set_scratch_buffer(&stream, page_address(scratch), PAGE_SIZE);
99424380
BS
527
528 do {
529 status = xdr_decode(desc, entry, &stream);
8cd51a0c
TM
530 if (status != 0) {
531 if (status == -EAGAIN)
532 status = 0;
99424380 533 break;
8cd51a0c 534 }
99424380 535
5c346854
TM
536 count++;
537
47c716cb 538 if (desc->plus != 0)
d39ab9de 539 nfs_prime_dcache(desc->file->f_path.dentry, entry);
8cd51a0c
TM
540
541 status = nfs_readdir_add_to_array(entry, page);
542 if (status != 0)
543 break;
99424380
BS
544 } while (!entry->eof);
545
47c716cb 546 if (count == 0 || (status == -EBADCOOKIE && entry->eof != 0)) {
99424380 547 array = nfs_readdir_get_array(page);
8cd51a0c
TM
548 if (!IS_ERR(array)) {
549 array->eof_index = array->size;
550 status = 0;
551 nfs_readdir_release_array(page);
5c346854
TM
552 } else
553 status = PTR_ERR(array);
1da177e4 554 }
6650239a
TM
555
556 put_page(scratch);
8cd51a0c 557 return status;
56e4ebf8
BS
558}
559
560static
561void nfs_readdir_free_pagearray(struct page **pages, unsigned int npages)
562{
563 unsigned int i;
564 for (i = 0; i < npages; i++)
565 put_page(pages[i]);
566}
567
568static
569void nfs_readdir_free_large_page(void *ptr, struct page **pages,
570 unsigned int npages)
571{
56e4ebf8
BS
572 nfs_readdir_free_pagearray(pages, npages);
573}
574
575/*
576 * nfs_readdir_large_page will allocate pages that must be freed with a call
577 * to nfs_readdir_free_large_page
578 */
579static
6650239a 580int nfs_readdir_large_page(struct page **pages, unsigned int npages)
56e4ebf8 581{
56e4ebf8
BS
582 unsigned int i;
583
584 for (i = 0; i < npages; i++) {
585 struct page *page = alloc_page(GFP_KERNEL);
586 if (page == NULL)
587 goto out_freepages;
588 pages[i] = page;
589 }
6650239a 590 return 0;
56e4ebf8 591
56e4ebf8
BS
592out_freepages:
593 nfs_readdir_free_pagearray(pages, i);
6650239a 594 return -ENOMEM;
1da177e4
LT
595}
596
d1bacf9e
BS
597static
598int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t *desc, struct page *page, struct inode *inode)
00a92642 599{
56e4ebf8
BS
600 struct page *pages[NFS_MAX_READDIR_PAGES];
601 void *pages_ptr = NULL;
d1bacf9e
BS
602 struct nfs_entry entry;
603 struct file *file = desc->file;
604 struct nfs_cache_array *array;
8cd51a0c 605 int status = -ENOMEM;
56e4ebf8 606 unsigned int array_size = ARRAY_SIZE(pages);
d1bacf9e
BS
607
608 entry.prev_cookie = 0;
0aded708 609 entry.cookie = desc->last_cookie;
d1bacf9e
BS
610 entry.eof = 0;
611 entry.fh = nfs_alloc_fhandle();
612 entry.fattr = nfs_alloc_fattr();
573c4e1e 613 entry.server = NFS_SERVER(inode);
d1bacf9e
BS
614 if (entry.fh == NULL || entry.fattr == NULL)
615 goto out;
00a92642 616
d1bacf9e 617 array = nfs_readdir_get_array(page);
8cd51a0c
TM
618 if (IS_ERR(array)) {
619 status = PTR_ERR(array);
620 goto out;
621 }
d1bacf9e
BS
622 memset(array, 0, sizeof(struct nfs_cache_array));
623 array->eof_index = -1;
00a92642 624
6650239a
TM
625 status = nfs_readdir_large_page(pages, array_size);
626 if (status < 0)
d1bacf9e
BS
627 goto out_release_array;
628 do {
ac396128 629 unsigned int pglen;
56e4ebf8 630 status = nfs_readdir_xdr_filler(pages, desc, &entry, file, inode);
babddc72 631
d1bacf9e 632 if (status < 0)
00a92642 633 break;
ac396128 634 pglen = status;
6650239a 635 status = nfs_readdir_page_filler(desc, &entry, pages, page, pglen);
8cd51a0c
TM
636 if (status < 0) {
637 if (status == -ENOSPC)
638 status = 0;
639 break;
640 }
641 } while (array->eof_index < 0);
d1bacf9e 642
56e4ebf8 643 nfs_readdir_free_large_page(pages_ptr, pages, array_size);
d1bacf9e
BS
644out_release_array:
645 nfs_readdir_release_array(page);
646out:
647 nfs_free_fattr(entry.fattr);
648 nfs_free_fhandle(entry.fh);
00a92642
OG
649 return status;
650}
651
652/*
d1bacf9e
BS
653 * Now we cache directories properly, by converting xdr information
654 * to an array that can be used for lookups later. This results in
655 * fewer cache pages, since we can store more information on each page.
656 * We only need to convert from xdr once so future lookups are much simpler
1da177e4 657 */
d1bacf9e
BS
658static
659int nfs_readdir_filler(nfs_readdir_descriptor_t *desc, struct page* page)
1da177e4 660{
01cce933 661 struct inode *inode = desc->file->f_path.dentry->d_inode;
8cd51a0c 662 int ret;
1da177e4 663
8cd51a0c
TM
664 ret = nfs_readdir_xdr_to_array(desc, page, inode);
665 if (ret < 0)
d1bacf9e
BS
666 goto error;
667 SetPageUptodate(page);
1da177e4 668
d1bacf9e
BS
669 if (invalidate_inode_pages2_range(inode->i_mapping, page->index + 1, -1) < 0) {
670 /* Should never happen */
671 nfs_zap_mapping(inode, inode->i_mapping);
1da177e4 672 }
d1bacf9e
BS
673 unlock_page(page);
674 return 0;
675 error:
676 unlock_page(page);
8cd51a0c 677 return ret;
d1bacf9e 678}
1da177e4 679
d1bacf9e
BS
680static
681void cache_page_release(nfs_readdir_descriptor_t *desc)
682{
11de3b11
TM
683 if (!desc->page->mapping)
684 nfs_readdir_clear_array(desc->page);
d1bacf9e
BS
685 page_cache_release(desc->page);
686 desc->page = NULL;
687}
688
689static
690struct page *get_cache_page(nfs_readdir_descriptor_t *desc)
691{
8cd51a0c 692 return read_cache_page(desc->file->f_path.dentry->d_inode->i_mapping,
d1bacf9e 693 desc->page_index, (filler_t *)nfs_readdir_filler, desc);
1da177e4
LT
694}
695
696/*
d1bacf9e 697 * Returns 0 if desc->dir_cookie was found on page desc->page_index
1da177e4 698 */
d1bacf9e
BS
699static
700int find_cache_page(nfs_readdir_descriptor_t *desc)
701{
702 int res;
703
704 desc->page = get_cache_page(desc);
705 if (IS_ERR(desc->page))
706 return PTR_ERR(desc->page);
707
708 res = nfs_readdir_search_array(desc);
47c716cb
TM
709 if (res != 0)
710 cache_page_release(desc);
d1bacf9e
BS
711 return res;
712}
713
714/* Search for desc->dir_cookie from the beginning of the page cache */
1da177e4
LT
715static inline
716int readdir_search_pagecache(nfs_readdir_descriptor_t *desc)
717{
8cd51a0c 718 int res;
d1bacf9e 719
0aded708 720 if (desc->page_index == 0) {
8cd51a0c 721 desc->current_index = 0;
0aded708
TM
722 desc->last_cookie = 0;
723 }
47c716cb 724 do {
d1bacf9e 725 res = find_cache_page(desc);
47c716cb 726 } while (res == -EAGAIN);
1da177e4
LT
727 return res;
728}
729
1da177e4
LT
730/*
731 * Once we've found the start of the dirent within a page: fill 'er up...
732 */
733static
734int nfs_do_filldir(nfs_readdir_descriptor_t *desc, void *dirent,
735 filldir_t filldir)
736{
737 struct file *file = desc->file;
d1bacf9e
BS
738 int i = 0;
739 int res = 0;
740 struct nfs_cache_array *array = NULL;
8ef2ce3e
BS
741 struct nfs_open_dir_context *ctx = file->private_data;
742
743 if (ctx->duped != 0 && ctx->dup_cookie == *desc->dir_cookie) {
744 if (printk_ratelimit()) {
745 pr_notice("NFS: directory %s/%s contains a readdir loop. "
746 "Please contact your server vendor. "
747 "Offending cookie: %llu\n",
748 file->f_dentry->d_parent->d_name.name,
749 file->f_dentry->d_name.name,
750 *desc->dir_cookie);
751 }
752 res = -ELOOP;
753 goto out;
754 }
d1bacf9e
BS
755
756 array = nfs_readdir_get_array(desc->page);
e7c58e97
TM
757 if (IS_ERR(array)) {
758 res = PTR_ERR(array);
759 goto out;
760 }
d1bacf9e
BS
761
762 for (i = desc->cache_entry_index; i < array->size; i++) {
ece0b423 763 struct nfs_cache_array_entry *ent;
1da177e4 764
ece0b423
TM
765 ent = &array->array[i];
766 if (filldir(dirent, ent->string.name, ent->string.len,
0b26a0bf
TM
767 file->f_pos, nfs_compat_user_ino64(ent->ino),
768 ent->d_type) < 0) {
ece0b423 769 desc->eof = 1;
1da177e4 770 break;
ece0b423 771 }
00a92642 772 file->f_pos++;
d1bacf9e
BS
773 if (i < (array->size-1))
774 *desc->dir_cookie = array->array[i+1].cookie;
775 else
776 *desc->dir_cookie = array->last_cookie;
1da177e4 777 }
47c716cb 778 if (array->eof_index >= 0)
8cd51a0c 779 desc->eof = 1;
d1bacf9e
BS
780
781 nfs_readdir_release_array(desc->page);
e7c58e97 782out:
d1bacf9e 783 cache_page_release(desc);
1e7cb3dc
CL
784 dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n",
785 (unsigned long long)*desc->dir_cookie, res);
1da177e4
LT
786 return res;
787}
788
789/*
790 * If we cannot find a cookie in our cache, we suspect that this is
791 * because it points to a deleted file, so we ask the server to return
792 * whatever it thinks is the next entry. We then feed this to filldir.
793 * If all goes well, we should then be able to find our way round the
794 * cache on the next call to readdir_search_pagecache();
795 *
796 * NOTE: we cannot add the anonymous page to the pagecache because
797 * the data it contains might not be page aligned. Besides,
798 * we should already have a complete representation of the
799 * directory in the page cache by the time we get here.
800 */
801static inline
802int uncached_readdir(nfs_readdir_descriptor_t *desc, void *dirent,
803 filldir_t filldir)
804{
1da177e4
LT
805 struct page *page = NULL;
806 int status;
d1bacf9e 807 struct inode *inode = desc->file->f_path.dentry->d_inode;
1da177e4 808
1e7cb3dc
CL
809 dfprintk(DIRCACHE, "NFS: uncached_readdir() searching for cookie %Lu\n",
810 (unsigned long long)*desc->dir_cookie);
1da177e4
LT
811
812 page = alloc_page(GFP_HIGHUSER);
813 if (!page) {
814 status = -ENOMEM;
815 goto out;
816 }
d1bacf9e 817
7a8e1dc3 818 desc->page_index = 0;
0aded708 819 desc->last_cookie = *desc->dir_cookie;
7a8e1dc3
TM
820 desc->page = page;
821
85f8607e
TM
822 status = nfs_readdir_xdr_to_array(desc, page, inode);
823 if (status < 0)
1da177e4
LT
824 goto out_release;
825
826 status = nfs_do_filldir(desc, dirent, filldir);
827
1da177e4 828 out:
1e7cb3dc 829 dfprintk(DIRCACHE, "NFS: %s: returns %d\n",
3110ff80 830 __func__, status);
1da177e4
LT
831 return status;
832 out_release:
d1bacf9e 833 cache_page_release(desc);
1da177e4
LT
834 goto out;
835}
836
00a92642
OG
837/* The file offset position represents the dirent entry number. A
838 last cookie cache takes care of the common case of reading the
839 whole directory.
1da177e4
LT
840 */
841static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
842{
01cce933 843 struct dentry *dentry = filp->f_path.dentry;
1da177e4
LT
844 struct inode *inode = dentry->d_inode;
845 nfs_readdir_descriptor_t my_desc,
846 *desc = &my_desc;
480c2006 847 struct nfs_open_dir_context *dir_ctx = filp->private_data;
47c716cb 848 int res;
1da177e4 849
6da24bc9 850 dfprintk(FILE, "NFS: readdir(%s/%s) starting at cookie %llu\n",
1e7cb3dc
CL
851 dentry->d_parent->d_name.name, dentry->d_name.name,
852 (long long)filp->f_pos);
91d5b470
CL
853 nfs_inc_stats(inode, NFSIOS_VFSGETDENTS);
854
1da177e4 855 /*
00a92642 856 * filp->f_pos points to the dirent entry number.
f0dd2136 857 * *desc->dir_cookie has the cookie for the next entry. We have
00a92642
OG
858 * to either find the entry with the appropriate number or
859 * revalidate the cookie.
1da177e4
LT
860 */
861 memset(desc, 0, sizeof(*desc));
862
863 desc->file = filp;
480c2006 864 desc->dir_cookie = &dir_ctx->dir_cookie;
1da177e4
LT
865 desc->decode = NFS_PROTO(inode)->decode_dirent;
866 desc->plus = NFS_USE_READDIRPLUS(inode);
867
565277f6 868 nfs_block_sillyrename(dentry);
1cda707d 869 res = nfs_revalidate_mapping(inode, filp->f_mapping);
fccca7fc
TM
870 if (res < 0)
871 goto out;
872
47c716cb 873 do {
1da177e4 874 res = readdir_search_pagecache(desc);
00a92642 875
1da177e4 876 if (res == -EBADCOOKIE) {
ece0b423 877 res = 0;
1da177e4 878 /* This means either end of directory */
d1bacf9e 879 if (*desc->dir_cookie && desc->eof == 0) {
1da177e4
LT
880 /* Or that the server has 'lost' a cookie */
881 res = uncached_readdir(desc, dirent, filldir);
ece0b423 882 if (res == 0)
1da177e4
LT
883 continue;
884 }
1da177e4
LT
885 break;
886 }
887 if (res == -ETOOSMALL && desc->plus) {
3a10c30a 888 clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
1da177e4 889 nfs_zap_caches(inode);
baf57a09 890 desc->page_index = 0;
1da177e4 891 desc->plus = 0;
d1bacf9e 892 desc->eof = 0;
1da177e4
LT
893 continue;
894 }
895 if (res < 0)
896 break;
897
898 res = nfs_do_filldir(desc, dirent, filldir);
ece0b423 899 if (res < 0)
1da177e4 900 break;
47c716cb 901 } while (!desc->eof);
fccca7fc 902out:
565277f6 903 nfs_unblock_sillyrename(dentry);
1e7cb3dc
CL
904 if (res > 0)
905 res = 0;
aa49b4cf 906 dfprintk(FILE, "NFS: readdir(%s/%s) returns %d\n",
1e7cb3dc
CL
907 dentry->d_parent->d_name.name, dentry->d_name.name,
908 res);
909 return res;
1da177e4
LT
910}
911
10afec90 912static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int origin)
f0dd2136 913{
b84e06c5
CL
914 struct dentry *dentry = filp->f_path.dentry;
915 struct inode *inode = dentry->d_inode;
480c2006 916 struct nfs_open_dir_context *dir_ctx = filp->private_data;
b84e06c5 917
6da24bc9 918 dfprintk(FILE, "NFS: llseek dir(%s/%s, %lld, %d)\n",
b84e06c5
CL
919 dentry->d_parent->d_name.name,
920 dentry->d_name.name,
921 offset, origin);
922
923 mutex_lock(&inode->i_mutex);
f0dd2136
TM
924 switch (origin) {
925 case 1:
926 offset += filp->f_pos;
927 case 0:
928 if (offset >= 0)
929 break;
930 default:
931 offset = -EINVAL;
932 goto out;
933 }
934 if (offset != filp->f_pos) {
935 filp->f_pos = offset;
480c2006 936 dir_ctx->dir_cookie = 0;
8ef2ce3e 937 dir_ctx->duped = 0;
f0dd2136
TM
938 }
939out:
b84e06c5 940 mutex_unlock(&inode->i_mutex);
f0dd2136
TM
941 return offset;
942}
943
1da177e4
LT
944/*
945 * All directory operations under NFS are synchronous, so fsync()
946 * is a dummy operation.
947 */
7ea80859 948static int nfs_fsync_dir(struct file *filp, int datasync)
1da177e4 949{
7ea80859
CH
950 struct dentry *dentry = filp->f_path.dentry;
951
6da24bc9 952 dfprintk(FILE, "NFS: fsync dir(%s/%s) datasync %d\n",
1e7cb3dc
CL
953 dentry->d_parent->d_name.name, dentry->d_name.name,
954 datasync);
955
54917786 956 nfs_inc_stats(dentry->d_inode, NFSIOS_VFSFSYNC);
1da177e4
LT
957 return 0;
958}
959
bfc69a45
TM
960/**
961 * nfs_force_lookup_revalidate - Mark the directory as having changed
962 * @dir - pointer to directory inode
963 *
964 * This forces the revalidation code in nfs_lookup_revalidate() to do a
965 * full lookup on all child dentries of 'dir' whenever a change occurs
966 * on the server that might have invalidated our dcache.
967 *
968 * The caller should be holding dir->i_lock
969 */
970void nfs_force_lookup_revalidate(struct inode *dir)
971{
011935a0 972 NFS_I(dir)->cache_change_attribute++;
bfc69a45
TM
973}
974
1da177e4
LT
975/*
976 * A check for whether or not the parent directory has changed.
977 * In the case it has, we assume that the dentries are untrustworthy
978 * and may need to be looked up again.
979 */
c79ba787 980static int nfs_check_verifier(struct inode *dir, struct dentry *dentry)
1da177e4
LT
981{
982 if (IS_ROOT(dentry))
983 return 1;
4eec952e
TM
984 if (NFS_SERVER(dir)->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
985 return 0;
f2c77f4e
TM
986 if (!nfs_verify_change_attribute(dir, dentry->d_time))
987 return 0;
988 /* Revalidate nfsi->cache_change_attribute before we declare a match */
989 if (nfs_revalidate_inode(NFS_SERVER(dir), dir) < 0)
990 return 0;
991 if (!nfs_verify_change_attribute(dir, dentry->d_time))
992 return 0;
993 return 1;
1da177e4
LT
994}
995
1d6757fb
TM
996/*
997 * Return the intent data that applies to this particular path component
998 *
999 * Note that the current set of intents only apply to the very last
1000 * component of the path.
1001 * We check for this using LOOKUP_CONTINUE and LOOKUP_PARENT.
1002 */
34286d66
NP
1003static inline unsigned int nfs_lookup_check_intent(struct nameidata *nd,
1004 unsigned int mask)
1d6757fb
TM
1005{
1006 if (nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT))
1007 return 0;
1008 return nd->flags & mask;
1009}
1010
a12802ca
TM
1011/*
1012 * Use intent information to check whether or not we're going to do
1013 * an O_EXCL create using this path component.
1014 */
1015static int nfs_is_exclusive_create(struct inode *dir, struct nameidata *nd)
1016{
1017 if (NFS_PROTO(dir)->version == 2)
1018 return 0;
3516586a 1019 return nd && nfs_lookup_check_intent(nd, LOOKUP_EXCL);
a12802ca
TM
1020}
1021
1d6757fb
TM
1022/*
1023 * Inode and filehandle revalidation for lookups.
1024 *
1025 * We force revalidation in the cases where the VFS sets LOOKUP_REVAL,
1026 * or if the intent information indicates that we're about to open this
1027 * particular file and the "nocto" mount flag is not set.
1028 *
1029 */
1da177e4
LT
1030static inline
1031int nfs_lookup_verify_inode(struct inode *inode, struct nameidata *nd)
1032{
1033 struct nfs_server *server = NFS_SERVER(inode);
1034
36d43a43 1035 if (IS_AUTOMOUNT(inode))
4e99a1ff 1036 return 0;
1da177e4 1037 if (nd != NULL) {
1da177e4 1038 /* VFS wants an on-the-wire revalidation */
1d6757fb 1039 if (nd->flags & LOOKUP_REVAL)
1da177e4
LT
1040 goto out_force;
1041 /* This is an open(2) */
1d6757fb 1042 if (nfs_lookup_check_intent(nd, LOOKUP_OPEN) != 0 &&
4e0641a7
TM
1043 !(server->flags & NFS_MOUNT_NOCTO) &&
1044 (S_ISREG(inode->i_mode) ||
1045 S_ISDIR(inode->i_mode)))
1da177e4 1046 goto out_force;
4f48af45 1047 return 0;
1da177e4
LT
1048 }
1049 return nfs_revalidate_inode(server, inode);
1050out_force:
1051 return __nfs_revalidate_inode(server, inode);
1052}
1053
1054/*
1055 * We judge how long we want to trust negative
1056 * dentries by looking at the parent inode mtime.
1057 *
1058 * If parent mtime has changed, we revalidate, else we wait for a
1059 * period corresponding to the parent's attribute cache timeout value.
1060 */
1061static inline
1062int nfs_neg_need_reval(struct inode *dir, struct dentry *dentry,
1063 struct nameidata *nd)
1064{
1da177e4 1065 /* Don't revalidate a negative dentry if we're creating a new file */
1d6757fb 1066 if (nd != NULL && nfs_lookup_check_intent(nd, LOOKUP_CREATE) != 0)
1da177e4 1067 return 0;
4eec952e
TM
1068 if (NFS_SERVER(dir)->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG)
1069 return 1;
1da177e4
LT
1070 return !nfs_check_verifier(dir, dentry);
1071}
1072
1073/*
1074 * This is called every time the dcache has a lookup hit,
1075 * and we should check whether we can really trust that
1076 * lookup.
1077 *
1078 * NOTE! The hit can be a negative hit too, don't assume
1079 * we have an inode!
1080 *
1081 * If the parent directory is seen to have changed, we throw out the
1082 * cached dentry and do a new lookup.
1083 */
34286d66 1084static int nfs_lookup_revalidate(struct dentry *dentry, struct nameidata *nd)
1da177e4
LT
1085{
1086 struct inode *dir;
1087 struct inode *inode;
1088 struct dentry *parent;
e1fb4d05
TM
1089 struct nfs_fh *fhandle = NULL;
1090 struct nfs_fattr *fattr = NULL;
1da177e4 1091 int error;
1da177e4 1092
34286d66
NP
1093 if (nd->flags & LOOKUP_RCU)
1094 return -ECHILD;
1095
1da177e4 1096 parent = dget_parent(dentry);
1da177e4 1097 dir = parent->d_inode;
91d5b470 1098 nfs_inc_stats(dir, NFSIOS_DENTRYREVALIDATE);
1da177e4
LT
1099 inode = dentry->d_inode;
1100
1101 if (!inode) {
1102 if (nfs_neg_need_reval(dir, dentry, nd))
1103 goto out_bad;
1104 goto out_valid;
1105 }
1106
1107 if (is_bad_inode(inode)) {
1e7cb3dc 1108 dfprintk(LOOKUPCACHE, "%s: %s/%s has dud inode\n",
3110ff80 1109 __func__, dentry->d_parent->d_name.name,
1e7cb3dc 1110 dentry->d_name.name);
1da177e4
LT
1111 goto out_bad;
1112 }
1113
15860ab1
TM
1114 if (nfs_have_delegation(inode, FMODE_READ))
1115 goto out_set_verifier;
1116
1da177e4 1117 /* Force a full look up iff the parent directory has changed */
a12802ca 1118 if (!nfs_is_exclusive_create(dir, nd) && nfs_check_verifier(dir, dentry)) {
1da177e4
LT
1119 if (nfs_lookup_verify_inode(inode, nd))
1120 goto out_zap_parent;
1121 goto out_valid;
1122 }
1123
1124 if (NFS_STALE(inode))
1125 goto out_bad;
1126
e1fb4d05
TM
1127 error = -ENOMEM;
1128 fhandle = nfs_alloc_fhandle();
1129 fattr = nfs_alloc_fattr();
1130 if (fhandle == NULL || fattr == NULL)
1131 goto out_error;
1132
7c513058 1133 error = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, &dentry->d_name, fhandle, fattr);
1da177e4
LT
1134 if (error)
1135 goto out_bad;
e1fb4d05 1136 if (nfs_compare_fh(NFS_FH(inode), fhandle))
1da177e4 1137 goto out_bad;
e1fb4d05 1138 if ((error = nfs_refresh_inode(inode, fattr)) != 0)
1da177e4
LT
1139 goto out_bad;
1140
e1fb4d05
TM
1141 nfs_free_fattr(fattr);
1142 nfs_free_fhandle(fhandle);
15860ab1 1143out_set_verifier:
cf8ba45e 1144 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1da177e4 1145 out_valid:
1da177e4 1146 dput(parent);
1e7cb3dc 1147 dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is valid\n",
3110ff80 1148 __func__, dentry->d_parent->d_name.name,
1e7cb3dc 1149 dentry->d_name.name);
1da177e4
LT
1150 return 1;
1151out_zap_parent:
1152 nfs_zap_caches(dir);
1153 out_bad:
a1643a92 1154 nfs_mark_for_revalidate(dir);
1da177e4
LT
1155 if (inode && S_ISDIR(inode->i_mode)) {
1156 /* Purge readdir caches. */
1157 nfs_zap_caches(inode);
1158 /* If we have submounts, don't unhash ! */
1159 if (have_submounts(dentry))
1160 goto out_valid;
d9e80b7d
AV
1161 if (dentry->d_flags & DCACHE_DISCONNECTED)
1162 goto out_valid;
1da177e4
LT
1163 shrink_dcache_parent(dentry);
1164 }
1165 d_drop(dentry);
e1fb4d05
TM
1166 nfs_free_fattr(fattr);
1167 nfs_free_fhandle(fhandle);
1da177e4 1168 dput(parent);
1e7cb3dc 1169 dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is invalid\n",
3110ff80 1170 __func__, dentry->d_parent->d_name.name,
1e7cb3dc 1171 dentry->d_name.name);
1da177e4 1172 return 0;
e1fb4d05
TM
1173out_error:
1174 nfs_free_fattr(fattr);
1175 nfs_free_fhandle(fhandle);
1176 dput(parent);
1177 dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) lookup returned error %d\n",
1178 __func__, dentry->d_parent->d_name.name,
1179 dentry->d_name.name, error);
1180 return error;
1da177e4
LT
1181}
1182
1183/*
1184 * This is called from dput() when d_count is going to 0.
1185 */
fe15ce44 1186static int nfs_dentry_delete(const struct dentry *dentry)
1da177e4
LT
1187{
1188 dfprintk(VFS, "NFS: dentry_delete(%s/%s, %x)\n",
1189 dentry->d_parent->d_name.name, dentry->d_name.name,
1190 dentry->d_flags);
1191
77f11192
TM
1192 /* Unhash any dentry with a stale inode */
1193 if (dentry->d_inode != NULL && NFS_STALE(dentry->d_inode))
1194 return 1;
1195
1da177e4
LT
1196 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
1197 /* Unhash it, so that ->d_iput() would be called */
1198 return 1;
1199 }
1200 if (!(dentry->d_sb->s_flags & MS_ACTIVE)) {
1201 /* Unhash it, so that ancestors of killed async unlink
1202 * files will be cleaned up during umount */
1203 return 1;
1204 }
1205 return 0;
1206
1207}
1208
1b83d707
TM
1209static void nfs_drop_nlink(struct inode *inode)
1210{
1211 spin_lock(&inode->i_lock);
1212 if (inode->i_nlink > 0)
1213 drop_nlink(inode);
1214 spin_unlock(&inode->i_lock);
1215}
1216
1da177e4
LT
1217/*
1218 * Called when the dentry loses inode.
1219 * We use it to clean up silly-renamed files.
1220 */
1221static void nfs_dentry_iput(struct dentry *dentry, struct inode *inode)
1222{
83672d39
NB
1223 if (S_ISDIR(inode->i_mode))
1224 /* drop any readdir cache as it could easily be old */
1225 NFS_I(inode)->cache_validity |= NFS_INO_INVALID_DATA;
1226
1da177e4 1227 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
9a53c3a7 1228 drop_nlink(inode);
e4eff1a6 1229 nfs_complete_unlink(dentry, inode);
1da177e4 1230 }
1da177e4
LT
1231 iput(inode);
1232}
1233
b1942c5f
AV
1234static void nfs_d_release(struct dentry *dentry)
1235{
1236 /* free cached devname value, if it survived that far */
1237 if (unlikely(dentry->d_fsdata)) {
1238 if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
1239 WARN_ON(1);
1240 else
1241 kfree(dentry->d_fsdata);
1242 }
1243}
1244
f786aa90 1245const struct dentry_operations nfs_dentry_operations = {
1da177e4
LT
1246 .d_revalidate = nfs_lookup_revalidate,
1247 .d_delete = nfs_dentry_delete,
1248 .d_iput = nfs_dentry_iput,
36d43a43 1249 .d_automount = nfs_d_automount,
b1942c5f 1250 .d_release = nfs_d_release,
1da177e4
LT
1251};
1252
1da177e4
LT
1253static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
1254{
1255 struct dentry *res;
565277f6 1256 struct dentry *parent;
1da177e4 1257 struct inode *inode = NULL;
e1fb4d05
TM
1258 struct nfs_fh *fhandle = NULL;
1259 struct nfs_fattr *fattr = NULL;
1da177e4 1260 int error;
1da177e4
LT
1261
1262 dfprintk(VFS, "NFS: lookup(%s/%s)\n",
1263 dentry->d_parent->d_name.name, dentry->d_name.name);
91d5b470 1264 nfs_inc_stats(dir, NFSIOS_VFSLOOKUP);
1da177e4
LT
1265
1266 res = ERR_PTR(-ENAMETOOLONG);
1267 if (dentry->d_name.len > NFS_SERVER(dir)->namelen)
1268 goto out;
1269
fd684071
TM
1270 /*
1271 * If we're doing an exclusive create, optimize away the lookup
1272 * but don't hash the dentry.
1273 */
1274 if (nfs_is_exclusive_create(dir, nd)) {
1275 d_instantiate(dentry, NULL);
1276 res = NULL;
fc0f684c 1277 goto out;
fd684071 1278 }
1da177e4 1279
e1fb4d05
TM
1280 res = ERR_PTR(-ENOMEM);
1281 fhandle = nfs_alloc_fhandle();
1282 fattr = nfs_alloc_fattr();
1283 if (fhandle == NULL || fattr == NULL)
1284 goto out;
1285
565277f6
TM
1286 parent = dentry->d_parent;
1287 /* Protect against concurrent sillydeletes */
1288 nfs_block_sillyrename(parent);
7c513058 1289 error = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, &dentry->d_name, fhandle, fattr);
1da177e4
LT
1290 if (error == -ENOENT)
1291 goto no_entry;
1292 if (error < 0) {
1293 res = ERR_PTR(error);
565277f6 1294 goto out_unblock_sillyrename;
1da177e4 1295 }
e1fb4d05 1296 inode = nfs_fhget(dentry->d_sb, fhandle, fattr);
bf0c84f1 1297 res = ERR_CAST(inode);
03f28e3a 1298 if (IS_ERR(res))
565277f6 1299 goto out_unblock_sillyrename;
54ceac45 1300
1da177e4 1301no_entry:
54ceac45 1302 res = d_materialise_unique(dentry, inode);
9eaef27b
TM
1303 if (res != NULL) {
1304 if (IS_ERR(res))
565277f6 1305 goto out_unblock_sillyrename;
1da177e4 1306 dentry = res;
9eaef27b 1307 }
1da177e4 1308 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
565277f6
TM
1309out_unblock_sillyrename:
1310 nfs_unblock_sillyrename(parent);
1da177e4 1311out:
e1fb4d05
TM
1312 nfs_free_fattr(fattr);
1313 nfs_free_fhandle(fhandle);
1da177e4
LT
1314 return res;
1315}
1316
1317#ifdef CONFIG_NFS_V4
1318static int nfs_open_revalidate(struct dentry *, struct nameidata *);
1319
f786aa90 1320const struct dentry_operations nfs4_dentry_operations = {
1da177e4
LT
1321 .d_revalidate = nfs_open_revalidate,
1322 .d_delete = nfs_dentry_delete,
1323 .d_iput = nfs_dentry_iput,
36d43a43 1324 .d_automount = nfs_d_automount,
b1942c5f 1325 .d_release = nfs_d_release,
1da177e4
LT
1326};
1327
1d6757fb
TM
1328/*
1329 * Use intent information to determine whether we need to substitute
1330 * the NFSv4-style stateful OPEN for the LOOKUP call
1331 */
5584c306 1332static int is_atomic_open(struct nameidata *nd)
1da177e4 1333{
1d6757fb 1334 if (nd == NULL || nfs_lookup_check_intent(nd, LOOKUP_OPEN) == 0)
1da177e4
LT
1335 return 0;
1336 /* NFS does not (yet) have a stateful open for directories */
1337 if (nd->flags & LOOKUP_DIRECTORY)
1338 return 0;
1339 /* Are we trying to write to a read only partition? */
2c463e95
DH
1340 if (__mnt_is_readonly(nd->path.mnt) &&
1341 (nd->intent.open.flags & (O_CREAT|O_TRUNC|FMODE_WRITE)))
1da177e4
LT
1342 return 0;
1343 return 1;
1344}
1345
cd9a1c0e
TM
1346static struct nfs_open_context *nameidata_to_nfs_open_context(struct dentry *dentry, struct nameidata *nd)
1347{
cd9a1c0e
TM
1348 struct nfs_open_context *ctx;
1349 struct rpc_cred *cred;
1350 fmode_t fmode = nd->intent.open.flags & (FMODE_READ | FMODE_WRITE | FMODE_EXEC);
1351
1352 cred = rpc_lookup_cred();
1353 if (IS_ERR(cred))
1354 return ERR_CAST(cred);
3d4ff43d 1355 ctx = alloc_nfs_open_context(dentry, cred, fmode);
cd9a1c0e
TM
1356 put_rpccred(cred);
1357 if (ctx == NULL)
1358 return ERR_PTR(-ENOMEM);
1359 return ctx;
1360}
1361
1362static int do_open(struct inode *inode, struct file *filp)
1363{
1364 nfs_fscache_set_inode_cookie(inode, filp);
1365 return 0;
1366}
1367
1368static int nfs_intent_set_file(struct nameidata *nd, struct nfs_open_context *ctx)
1369{
1370 struct file *filp;
1371 int ret = 0;
1372
1373 /* If the open_intent is for execute, we have an extra check to make */
1374 if (ctx->mode & FMODE_EXEC) {
3d4ff43d 1375 ret = nfs_may_open(ctx->dentry->d_inode,
cd9a1c0e
TM
1376 ctx->cred,
1377 nd->intent.open.flags);
1378 if (ret < 0)
1379 goto out;
1380 }
3d4ff43d 1381 filp = lookup_instantiate_filp(nd, ctx->dentry, do_open);
cd9a1c0e
TM
1382 if (IS_ERR(filp))
1383 ret = PTR_ERR(filp);
1384 else
1385 nfs_file_set_open_context(filp, ctx);
1386out:
1387 put_nfs_open_context(ctx);
1388 return ret;
1389}
1390
1da177e4
LT
1391static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
1392{
cd9a1c0e
TM
1393 struct nfs_open_context *ctx;
1394 struct iattr attr;
1da177e4 1395 struct dentry *res = NULL;
f46e0bd3 1396 struct inode *inode;
cd9a1c0e 1397 int open_flags;
898f635c 1398 int err;
1da177e4 1399
1e7cb3dc
CL
1400 dfprintk(VFS, "NFS: atomic_lookup(%s/%ld), %s\n",
1401 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1402
1da177e4 1403 /* Check that we are indeed trying to open this file */
5584c306 1404 if (!is_atomic_open(nd))
1da177e4
LT
1405 goto no_open;
1406
1407 if (dentry->d_name.len > NFS_SERVER(dir)->namelen) {
1408 res = ERR_PTR(-ENAMETOOLONG);
1409 goto out;
1410 }
1da177e4 1411
d4d9cdcb
TM
1412 /* Let vfs_create() deal with O_EXCL. Instantiate, but don't hash
1413 * the dentry. */
3516586a 1414 if (nd->flags & LOOKUP_EXCL) {
d4d9cdcb 1415 d_instantiate(dentry, NULL);
02a913a7
TM
1416 goto out;
1417 }
1da177e4 1418
cd9a1c0e
TM
1419 ctx = nameidata_to_nfs_open_context(dentry, nd);
1420 res = ERR_CAST(ctx);
1421 if (IS_ERR(ctx))
1422 goto out;
1423
1424 open_flags = nd->intent.open.flags;
1425 if (nd->flags & LOOKUP_CREATE) {
1426 attr.ia_mode = nd->intent.open.create_mode;
1427 attr.ia_valid = ATTR_MODE;
a8a5da99 1428 attr.ia_mode &= ~current_umask();
cd9a1c0e 1429 } else {
898f635c 1430 open_flags &= ~(O_EXCL | O_CREAT);
cd9a1c0e 1431 attr.ia_valid = 0;
cd9a1c0e
TM
1432 }
1433
1da177e4 1434 /* Open the file on the server */
f46e0bd3 1435 nfs_block_sillyrename(dentry->d_parent);
2b484297 1436 inode = NFS_PROTO(dir)->open_context(dir, ctx, open_flags, &attr);
f46e0bd3
TM
1437 if (IS_ERR(inode)) {
1438 nfs_unblock_sillyrename(dentry->d_parent);
cd9a1c0e 1439 put_nfs_open_context(ctx);
f46e0bd3 1440 switch (PTR_ERR(inode)) {
1da177e4
LT
1441 /* Make a negative dentry */
1442 case -ENOENT:
f46e0bd3 1443 d_add(dentry, NULL);
02a913a7
TM
1444 res = NULL;
1445 goto out;
1da177e4 1446 /* This turned out not to be a regular file */
6f926b5b
TM
1447 case -ENOTDIR:
1448 goto no_open;
1da177e4
LT
1449 case -ELOOP:
1450 if (!(nd->intent.open.flags & O_NOFOLLOW))
1451 goto no_open;
23ebbd9a 1452 /* case -EISDIR: */
1da177e4
LT
1453 /* case -EINVAL: */
1454 default:
f46e0bd3 1455 res = ERR_CAST(inode);
1da177e4
LT
1456 goto out;
1457 }
cd9a1c0e 1458 }
f46e0bd3 1459 res = d_add_unique(dentry, inode);
898f635c 1460 nfs_unblock_sillyrename(dentry->d_parent);
f46e0bd3 1461 if (res != NULL) {
3d4ff43d
AV
1462 dput(ctx->dentry);
1463 ctx->dentry = dget(res);
1da177e4 1464 dentry = res;
f46e0bd3 1465 }
898f635c
TM
1466 err = nfs_intent_set_file(nd, ctx);
1467 if (err < 0) {
1468 if (res != NULL)
1469 dput(res);
1470 return ERR_PTR(err);
1471 }
1da177e4 1472out:
f46e0bd3 1473 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1da177e4
LT
1474 return res;
1475no_open:
1476 return nfs_lookup(dir, dentry, nd);
1477}
1478
1479static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
1480{
1481 struct dentry *parent = NULL;
657e94b6 1482 struct inode *inode;
1da177e4 1483 struct inode *dir;
b8d4cadd 1484 struct nfs_open_context *ctx;
1da177e4
LT
1485 int openflags, ret = 0;
1486
657e94b6
NP
1487 if (nd->flags & LOOKUP_RCU)
1488 return -ECHILD;
1489
1490 inode = dentry->d_inode;
1f063d2c 1491 if (!is_atomic_open(nd) || d_mountpoint(dentry))
5584c306 1492 goto no_open;
2b484297 1493
1da177e4
LT
1494 parent = dget_parent(dentry);
1495 dir = parent->d_inode;
2b484297 1496
1da177e4
LT
1497 /* We can't create new files in nfs_open_revalidate(), so we
1498 * optimize away revalidation of negative dentries.
1499 */
216d5d06
TM
1500 if (inode == NULL) {
1501 if (!nfs_neg_need_reval(dir, dentry, nd))
1502 ret = 1;
1da177e4 1503 goto out;
216d5d06
TM
1504 }
1505
1da177e4
LT
1506 /* NFS only supports OPEN on regular files */
1507 if (!S_ISREG(inode->i_mode))
5584c306 1508 goto no_open_dput;
1da177e4
LT
1509 openflags = nd->intent.open.flags;
1510 /* We cannot do exclusive creation on a positive dentry */
1511 if ((openflags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL))
5584c306 1512 goto no_open_dput;
1da177e4 1513 /* We can't create new files, or truncate existing ones here */
0a377cff 1514 openflags &= ~(O_CREAT|O_EXCL|O_TRUNC);
1da177e4 1515
b8d4cadd
TM
1516 ctx = nameidata_to_nfs_open_context(dentry, nd);
1517 ret = PTR_ERR(ctx);
1518 if (IS_ERR(ctx))
1519 goto out;
1da177e4 1520 /*
1b1dcc1b 1521 * Note: we're not holding inode->i_mutex and so may be racing with
1da177e4
LT
1522 * operations that change the directory. We therefore save the
1523 * change attribute *before* we do the RPC call.
1524 */
2b484297 1525 inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, NULL);
535918f1
TM
1526 if (IS_ERR(inode)) {
1527 ret = PTR_ERR(inode);
1528 switch (ret) {
1529 case -EPERM:
1530 case -EACCES:
1531 case -EDQUOT:
1532 case -ENOSPC:
1533 case -EROFS:
1534 goto out_put_ctx;
1535 default:
1536 goto out_drop;
1537 }
1538 }
1539 iput(inode);
898f635c 1540 if (inode != dentry->d_inode)
535918f1 1541 goto out_drop;
898f635c
TM
1542
1543 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1544 ret = nfs_intent_set_file(nd, ctx);
1545 if (ret >= 0)
1546 ret = 1;
1da177e4
LT
1547out:
1548 dput(parent);
1da177e4 1549 return ret;
535918f1
TM
1550out_drop:
1551 d_drop(dentry);
1552 ret = 0;
1553out_put_ctx:
1554 put_nfs_open_context(ctx);
1555 goto out;
1556
5584c306 1557no_open_dput:
1da177e4 1558 dput(parent);
5584c306 1559no_open:
1da177e4
LT
1560 return nfs_lookup_revalidate(dentry, nd);
1561}
c0204fd2
TM
1562
1563static int nfs_open_create(struct inode *dir, struct dentry *dentry, int mode,
1564 struct nameidata *nd)
1565{
1566 struct nfs_open_context *ctx = NULL;
1567 struct iattr attr;
1568 int error;
1569 int open_flags = 0;
1570
1571 dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
1572 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1573
1574 attr.ia_mode = mode;
1575 attr.ia_valid = ATTR_MODE;
1576
1577 if ((nd->flags & LOOKUP_CREATE) != 0) {
1578 open_flags = nd->intent.open.flags;
1579
1580 ctx = nameidata_to_nfs_open_context(dentry, nd);
1581 error = PTR_ERR(ctx);
1582 if (IS_ERR(ctx))
898f635c 1583 goto out_err_drop;
c0204fd2
TM
1584 }
1585
1586 error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, ctx);
1587 if (error != 0)
1588 goto out_put_ctx;
898f635c
TM
1589 if (ctx != NULL) {
1590 error = nfs_intent_set_file(nd, ctx);
1591 if (error < 0)
1592 goto out_err;
1593 }
c0204fd2
TM
1594 return 0;
1595out_put_ctx:
1596 if (ctx != NULL)
1597 put_nfs_open_context(ctx);
898f635c 1598out_err_drop:
c0204fd2 1599 d_drop(dentry);
898f635c 1600out_err:
c0204fd2
TM
1601 return error;
1602}
1603
1da177e4
LT
1604#endif /* CONFIG_NFSV4 */
1605
1da177e4
LT
1606/*
1607 * Code common to create, mkdir, and mknod.
1608 */
1609int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fhandle,
1610 struct nfs_fattr *fattr)
1611{
fab728e1
TM
1612 struct dentry *parent = dget_parent(dentry);
1613 struct inode *dir = parent->d_inode;
1da177e4
LT
1614 struct inode *inode;
1615 int error = -EACCES;
1616
fab728e1
TM
1617 d_drop(dentry);
1618
1da177e4
LT
1619 /* We may have been initialized further down */
1620 if (dentry->d_inode)
fab728e1 1621 goto out;
1da177e4 1622 if (fhandle->size == 0) {
7c513058 1623 error = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, &dentry->d_name, fhandle, fattr);
1da177e4 1624 if (error)
fab728e1 1625 goto out_error;
1da177e4 1626 }
5724ab37 1627 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1da177e4
LT
1628 if (!(fattr->valid & NFS_ATTR_FATTR)) {
1629 struct nfs_server *server = NFS_SB(dentry->d_sb);
8fa5c000 1630 error = server->nfs_client->rpc_ops->getattr(server, fhandle, fattr);
1da177e4 1631 if (error < 0)
fab728e1 1632 goto out_error;
1da177e4 1633 }
1da177e4 1634 inode = nfs_fhget(dentry->d_sb, fhandle, fattr);
03f28e3a
TM
1635 error = PTR_ERR(inode);
1636 if (IS_ERR(inode))
fab728e1
TM
1637 goto out_error;
1638 d_add(dentry, inode);
1639out:
1640 dput(parent);
1da177e4 1641 return 0;
fab728e1
TM
1642out_error:
1643 nfs_mark_for_revalidate(dir);
1644 dput(parent);
1645 return error;
1da177e4
LT
1646}
1647
1648/*
1649 * Following a failed create operation, we drop the dentry rather
1650 * than retain a negative dentry. This avoids a problem in the event
1651 * that the operation succeeded on the server, but an error in the
1652 * reply path made it appear to have failed.
1653 */
1654static int nfs_create(struct inode *dir, struct dentry *dentry, int mode,
1655 struct nameidata *nd)
1656{
1657 struct iattr attr;
1658 int error;
8a0eebf6 1659 int open_flags = 0;
1da177e4 1660
1e7cb3dc
CL
1661 dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
1662 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1da177e4
LT
1663
1664 attr.ia_mode = mode;
1665 attr.ia_valid = ATTR_MODE;
1666
8a0eebf6
TM
1667 if ((nd->flags & LOOKUP_CREATE) != 0)
1668 open_flags = nd->intent.open.flags;
1669
1670 error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, NULL);
1da177e4
LT
1671 if (error != 0)
1672 goto out_err;
1da177e4
LT
1673 return 0;
1674out_err:
1da177e4
LT
1675 d_drop(dentry);
1676 return error;
1677}
1678
1679/*
1680 * See comments for nfs_proc_create regarding failed operations.
1681 */
1682static int
1683nfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
1684{
1685 struct iattr attr;
1686 int status;
1687
1e7cb3dc
CL
1688 dfprintk(VFS, "NFS: mknod(%s/%ld), %s\n",
1689 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1da177e4
LT
1690
1691 if (!new_valid_dev(rdev))
1692 return -EINVAL;
1693
1694 attr.ia_mode = mode;
1695 attr.ia_valid = ATTR_MODE;
1696
1da177e4 1697 status = NFS_PROTO(dir)->mknod(dir, dentry, &attr, rdev);
1da177e4
LT
1698 if (status != 0)
1699 goto out_err;
1da177e4
LT
1700 return 0;
1701out_err:
1da177e4
LT
1702 d_drop(dentry);
1703 return status;
1704}
1705
1706/*
1707 * See comments for nfs_proc_create regarding failed operations.
1708 */
1709static int nfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
1710{
1711 struct iattr attr;
1712 int error;
1713
1e7cb3dc
CL
1714 dfprintk(VFS, "NFS: mkdir(%s/%ld), %s\n",
1715 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1da177e4
LT
1716
1717 attr.ia_valid = ATTR_MODE;
1718 attr.ia_mode = mode | S_IFDIR;
1719
1da177e4 1720 error = NFS_PROTO(dir)->mkdir(dir, dentry, &attr);
1da177e4
LT
1721 if (error != 0)
1722 goto out_err;
1da177e4
LT
1723 return 0;
1724out_err:
1725 d_drop(dentry);
1da177e4
LT
1726 return error;
1727}
1728
d45b9d8b
TM
1729static void nfs_dentry_handle_enoent(struct dentry *dentry)
1730{
1731 if (dentry->d_inode != NULL && !d_unhashed(dentry))
1732 d_delete(dentry);
1733}
1734
1da177e4
LT
1735static int nfs_rmdir(struct inode *dir, struct dentry *dentry)
1736{
1737 int error;
1738
1e7cb3dc
CL
1739 dfprintk(VFS, "NFS: rmdir(%s/%ld), %s\n",
1740 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1da177e4 1741
1da177e4
LT
1742 error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name);
1743 /* Ensure the VFS deletes this inode */
1744 if (error == 0 && dentry->d_inode != NULL)
ce71ec36 1745 clear_nlink(dentry->d_inode);
d45b9d8b
TM
1746 else if (error == -ENOENT)
1747 nfs_dentry_handle_enoent(dentry);
1da177e4
LT
1748
1749 return error;
1750}
1751
1da177e4
LT
1752/*
1753 * Remove a file after making sure there are no pending writes,
1754 * and after checking that the file has only one user.
1755 *
1756 * We invalidate the attribute cache and free the inode prior to the operation
1757 * to avoid possible races if the server reuses the inode.
1758 */
1759static int nfs_safe_remove(struct dentry *dentry)
1760{
1761 struct inode *dir = dentry->d_parent->d_inode;
1762 struct inode *inode = dentry->d_inode;
1763 int error = -EBUSY;
1764
1765 dfprintk(VFS, "NFS: safe_remove(%s/%s)\n",
1766 dentry->d_parent->d_name.name, dentry->d_name.name);
1767
1768 /* If the dentry was sillyrenamed, we simply call d_delete() */
1769 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
1770 error = 0;
1771 goto out;
1772 }
1773
1da177e4 1774 if (inode != NULL) {
cae7a073 1775 nfs_inode_return_delegation(inode);
1da177e4
LT
1776 error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
1777 /* The VFS may want to delete this inode */
1778 if (error == 0)
1b83d707 1779 nfs_drop_nlink(inode);
5ba7cc48 1780 nfs_mark_for_revalidate(inode);
1da177e4
LT
1781 } else
1782 error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
d45b9d8b
TM
1783 if (error == -ENOENT)
1784 nfs_dentry_handle_enoent(dentry);
1da177e4
LT
1785out:
1786 return error;
1787}
1788
1789/* We do silly rename. In case sillyrename() returns -EBUSY, the inode
1790 * belongs to an active ".nfs..." file and we return -EBUSY.
1791 *
1792 * If sillyrename() returns 0, we do nothing, otherwise we unlink.
1793 */
1794static int nfs_unlink(struct inode *dir, struct dentry *dentry)
1795{
1796 int error;
1797 int need_rehash = 0;
1798
1799 dfprintk(VFS, "NFS: unlink(%s/%ld, %s)\n", dir->i_sb->s_id,
1800 dir->i_ino, dentry->d_name.name);
1801
1da177e4 1802 spin_lock(&dentry->d_lock);
b7ab39f6 1803 if (dentry->d_count > 1) {
1da177e4 1804 spin_unlock(&dentry->d_lock);
ccfeb506
TM
1805 /* Start asynchronous writeout of the inode */
1806 write_inode_now(dentry->d_inode, 0);
1da177e4 1807 error = nfs_sillyrename(dir, dentry);
1da177e4
LT
1808 return error;
1809 }
1810 if (!d_unhashed(dentry)) {
1811 __d_drop(dentry);
1812 need_rehash = 1;
1813 }
1814 spin_unlock(&dentry->d_lock);
1da177e4 1815 error = nfs_safe_remove(dentry);
d45b9d8b 1816 if (!error || error == -ENOENT) {
1da177e4
LT
1817 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1818 } else if (need_rehash)
1819 d_rehash(dentry);
1da177e4
LT
1820 return error;
1821}
1822
873101b3
CL
1823/*
1824 * To create a symbolic link, most file systems instantiate a new inode,
1825 * add a page to it containing the path, then write it out to the disk
1826 * using prepare_write/commit_write.
1827 *
1828 * Unfortunately the NFS client can't create the in-core inode first
1829 * because it needs a file handle to create an in-core inode (see
1830 * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the
1831 * symlink request has completed on the server.
1832 *
1833 * So instead we allocate a raw page, copy the symname into it, then do
1834 * the SYMLINK request with the page as the buffer. If it succeeds, we
1835 * now have a new file handle and can instantiate an in-core NFS inode
1836 * and move the raw page into its mapping.
1837 */
1838static int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
1da177e4 1839{
873101b3
CL
1840 struct pagevec lru_pvec;
1841 struct page *page;
1842 char *kaddr;
1da177e4 1843 struct iattr attr;
873101b3 1844 unsigned int pathlen = strlen(symname);
1da177e4
LT
1845 int error;
1846
1847 dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s)\n", dir->i_sb->s_id,
1848 dir->i_ino, dentry->d_name.name, symname);
1849
873101b3
CL
1850 if (pathlen > PAGE_SIZE)
1851 return -ENAMETOOLONG;
1da177e4 1852
873101b3
CL
1853 attr.ia_mode = S_IFLNK | S_IRWXUGO;
1854 attr.ia_valid = ATTR_MODE;
1da177e4 1855
83d93f22 1856 page = alloc_page(GFP_HIGHUSER);
76566991 1857 if (!page)
873101b3 1858 return -ENOMEM;
873101b3
CL
1859
1860 kaddr = kmap_atomic(page, KM_USER0);
1861 memcpy(kaddr, symname, pathlen);
1862 if (pathlen < PAGE_SIZE)
1863 memset(kaddr + pathlen, 0, PAGE_SIZE - pathlen);
1864 kunmap_atomic(kaddr, KM_USER0);
1865
94a6d753 1866 error = NFS_PROTO(dir)->symlink(dir, dentry, page, pathlen, &attr);
873101b3
CL
1867 if (error != 0) {
1868 dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s) error %d\n",
1869 dir->i_sb->s_id, dir->i_ino,
1870 dentry->d_name.name, symname, error);
1da177e4 1871 d_drop(dentry);
873101b3 1872 __free_page(page);
873101b3
CL
1873 return error;
1874 }
1875
1876 /*
1877 * No big deal if we can't add this page to the page cache here.
1878 * READLINK will get the missing page from the server if needed.
1879 */
1880 pagevec_init(&lru_pvec, 0);
1881 if (!add_to_page_cache(page, dentry->d_inode->i_mapping, 0,
1882 GFP_KERNEL)) {
39cf8a13 1883 pagevec_add(&lru_pvec, page);
4f98a2fe 1884 pagevec_lru_add_file(&lru_pvec);
873101b3
CL
1885 SetPageUptodate(page);
1886 unlock_page(page);
1887 } else
1888 __free_page(page);
1889
873101b3 1890 return 0;
1da177e4
LT
1891}
1892
1893static int
1894nfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
1895{
1896 struct inode *inode = old_dentry->d_inode;
1897 int error;
1898
1899 dfprintk(VFS, "NFS: link(%s/%s -> %s/%s)\n",
1900 old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
1901 dentry->d_parent->d_name.name, dentry->d_name.name);
1902
9a3936aa
TM
1903 nfs_inode_return_delegation(inode);
1904
9697d234 1905 d_drop(dentry);
1da177e4 1906 error = NFS_PROTO(dir)->link(inode, dir, &dentry->d_name);
cf809556 1907 if (error == 0) {
7de9c6ee 1908 ihold(inode);
9697d234 1909 d_add(dentry, inode);
cf809556 1910 }
1da177e4
LT
1911 return error;
1912}
1913
1914/*
1915 * RENAME
1916 * FIXME: Some nfsds, like the Linux user space nfsd, may generate a
1917 * different file handle for the same inode after a rename (e.g. when
1918 * moving to a different directory). A fail-safe method to do so would
1919 * be to look up old_dir/old_name, create a link to new_dir/new_name and
1920 * rename the old file using the sillyrename stuff. This way, the original
1921 * file in old_dir will go away when the last process iput()s the inode.
1922 *
1923 * FIXED.
1924 *
1925 * It actually works quite well. One needs to have the possibility for
1926 * at least one ".nfs..." file in each directory the file ever gets
1927 * moved or linked to which happens automagically with the new
1928 * implementation that only depends on the dcache stuff instead of
1929 * using the inode layer
1930 *
1931 * Unfortunately, things are a little more complicated than indicated
1932 * above. For a cross-directory move, we want to make sure we can get
1933 * rid of the old inode after the operation. This means there must be
1934 * no pending writes (if it's a file), and the use count must be 1.
1935 * If these conditions are met, we can drop the dentries before doing
1936 * the rename.
1937 */
1938static int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
1939 struct inode *new_dir, struct dentry *new_dentry)
1940{
1941 struct inode *old_inode = old_dentry->d_inode;
1942 struct inode *new_inode = new_dentry->d_inode;
1943 struct dentry *dentry = NULL, *rehash = NULL;
1944 int error = -EBUSY;
1945
1da177e4
LT
1946 dfprintk(VFS, "NFS: rename(%s/%s -> %s/%s, ct=%d)\n",
1947 old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
1948 new_dentry->d_parent->d_name.name, new_dentry->d_name.name,
b7ab39f6 1949 new_dentry->d_count);
1da177e4
LT
1950
1951 /*
28f79a1a
MS
1952 * For non-directories, check whether the target is busy and if so,
1953 * make a copy of the dentry and then do a silly-rename. If the
1954 * silly-rename succeeds, the copied dentry is hashed and becomes
1955 * the new target.
1da177e4 1956 */
27226104
MS
1957 if (new_inode && !S_ISDIR(new_inode->i_mode)) {
1958 /*
1959 * To prevent any new references to the target during the
1960 * rename, we unhash the dentry in advance.
1961 */
1962 if (!d_unhashed(new_dentry)) {
1963 d_drop(new_dentry);
1964 rehash = new_dentry;
1965 }
1da177e4 1966
b7ab39f6 1967 if (new_dentry->d_count > 2) {
27226104
MS
1968 int err;
1969
1970 /* copy the target dentry's name */
1971 dentry = d_alloc(new_dentry->d_parent,
1972 &new_dentry->d_name);
1973 if (!dentry)
1974 goto out;
1975
1976 /* silly-rename the existing target ... */
1977 err = nfs_sillyrename(new_dir, new_dentry);
24e93025 1978 if (err)
27226104 1979 goto out;
24e93025
MS
1980
1981 new_dentry = dentry;
56335936 1982 rehash = NULL;
24e93025 1983 new_inode = NULL;
27226104 1984 }
b1e4adf4 1985 }
1da177e4 1986
cae7a073 1987 nfs_inode_return_delegation(old_inode);
b1e4adf4 1988 if (new_inode != NULL)
24174119 1989 nfs_inode_return_delegation(new_inode);
1da177e4 1990
1da177e4
LT
1991 error = NFS_PROTO(old_dir)->rename(old_dir, &old_dentry->d_name,
1992 new_dir, &new_dentry->d_name);
5ba7cc48 1993 nfs_mark_for_revalidate(old_inode);
1da177e4
LT
1994out:
1995 if (rehash)
1996 d_rehash(rehash);
1997 if (!error) {
b1e4adf4
TM
1998 if (new_inode != NULL)
1999 nfs_drop_nlink(new_inode);
349457cc 2000 d_move(old_dentry, new_dentry);
8fb559f8
CL
2001 nfs_set_verifier(new_dentry,
2002 nfs_save_change_attribute(new_dir));
d45b9d8b
TM
2003 } else if (error == -ENOENT)
2004 nfs_dentry_handle_enoent(old_dentry);
1da177e4
LT
2005
2006 /* new dentry created? */
2007 if (dentry)
2008 dput(dentry);
1da177e4
LT
2009 return error;
2010}
2011
cfcea3e8
TM
2012static DEFINE_SPINLOCK(nfs_access_lru_lock);
2013static LIST_HEAD(nfs_access_lru_list);
2014static atomic_long_t nfs_access_nr_entries;
2015
1c3c07e9
TM
2016static void nfs_access_free_entry(struct nfs_access_entry *entry)
2017{
2018 put_rpccred(entry->cred);
2019 kfree(entry);
cfcea3e8
TM
2020 smp_mb__before_atomic_dec();
2021 atomic_long_dec(&nfs_access_nr_entries);
2022 smp_mb__after_atomic_dec();
1c3c07e9
TM
2023}
2024
1a81bb8a
TM
2025static void nfs_access_free_list(struct list_head *head)
2026{
2027 struct nfs_access_entry *cache;
2028
2029 while (!list_empty(head)) {
2030 cache = list_entry(head->next, struct nfs_access_entry, lru);
2031 list_del(&cache->lru);
2032 nfs_access_free_entry(cache);
2033 }
2034}
2035
1495f230
YH
2036int nfs_access_cache_shrinker(struct shrinker *shrink,
2037 struct shrink_control *sc)
979df72e
TM
2038{
2039 LIST_HEAD(head);
aa510da5 2040 struct nfs_inode *nfsi, *next;
979df72e 2041 struct nfs_access_entry *cache;
1495f230
YH
2042 int nr_to_scan = sc->nr_to_scan;
2043 gfp_t gfp_mask = sc->gfp_mask;
979df72e 2044
61d5eb29
TM
2045 if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
2046 return (nr_to_scan == 0) ? 0 : -1;
9c7e7e23 2047
a50f7951 2048 spin_lock(&nfs_access_lru_lock);
aa510da5 2049 list_for_each_entry_safe(nfsi, next, &nfs_access_lru_list, access_cache_inode_lru) {
979df72e
TM
2050 struct inode *inode;
2051
2052 if (nr_to_scan-- == 0)
2053 break;
9c7e7e23 2054 inode = &nfsi->vfs_inode;
979df72e
TM
2055 spin_lock(&inode->i_lock);
2056 if (list_empty(&nfsi->access_cache_entry_lru))
2057 goto remove_lru_entry;
2058 cache = list_entry(nfsi->access_cache_entry_lru.next,
2059 struct nfs_access_entry, lru);
2060 list_move(&cache->lru, &head);
2061 rb_erase(&cache->rb_node, &nfsi->access_cache);
2062 if (!list_empty(&nfsi->access_cache_entry_lru))
2063 list_move_tail(&nfsi->access_cache_inode_lru,
2064 &nfs_access_lru_list);
2065 else {
2066remove_lru_entry:
2067 list_del_init(&nfsi->access_cache_inode_lru);
9c7e7e23 2068 smp_mb__before_clear_bit();
979df72e 2069 clear_bit(NFS_INO_ACL_LRU_SET, &nfsi->flags);
9c7e7e23 2070 smp_mb__after_clear_bit();
979df72e 2071 }
59844a9b 2072 spin_unlock(&inode->i_lock);
979df72e
TM
2073 }
2074 spin_unlock(&nfs_access_lru_lock);
1a81bb8a 2075 nfs_access_free_list(&head);
979df72e
TM
2076 return (atomic_long_read(&nfs_access_nr_entries) / 100) * sysctl_vfs_cache_pressure;
2077}
2078
1a81bb8a 2079static void __nfs_access_zap_cache(struct nfs_inode *nfsi, struct list_head *head)
1da177e4 2080{
1c3c07e9 2081 struct rb_root *root_node = &nfsi->access_cache;
1a81bb8a 2082 struct rb_node *n;
1c3c07e9
TM
2083 struct nfs_access_entry *entry;
2084
2085 /* Unhook entries from the cache */
2086 while ((n = rb_first(root_node)) != NULL) {
2087 entry = rb_entry(n, struct nfs_access_entry, rb_node);
2088 rb_erase(n, root_node);
1a81bb8a 2089 list_move(&entry->lru, head);
1c3c07e9
TM
2090 }
2091 nfsi->cache_validity &= ~NFS_INO_INVALID_ACCESS;
1da177e4
LT
2092}
2093
1c3c07e9 2094void nfs_access_zap_cache(struct inode *inode)
1da177e4 2095{
1a81bb8a
TM
2096 LIST_HEAD(head);
2097
2098 if (test_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags) == 0)
2099 return;
cfcea3e8 2100 /* Remove from global LRU init */
1a81bb8a
TM
2101 spin_lock(&nfs_access_lru_lock);
2102 if (test_and_clear_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags))
cfcea3e8 2103 list_del_init(&NFS_I(inode)->access_cache_inode_lru);
cfcea3e8 2104
1c3c07e9 2105 spin_lock(&inode->i_lock);
1a81bb8a
TM
2106 __nfs_access_zap_cache(NFS_I(inode), &head);
2107 spin_unlock(&inode->i_lock);
2108 spin_unlock(&nfs_access_lru_lock);
2109 nfs_access_free_list(&head);
1c3c07e9 2110}
1da177e4 2111
1c3c07e9
TM
2112static struct nfs_access_entry *nfs_access_search_rbtree(struct inode *inode, struct rpc_cred *cred)
2113{
2114 struct rb_node *n = NFS_I(inode)->access_cache.rb_node;
2115 struct nfs_access_entry *entry;
2116
2117 while (n != NULL) {
2118 entry = rb_entry(n, struct nfs_access_entry, rb_node);
2119
2120 if (cred < entry->cred)
2121 n = n->rb_left;
2122 else if (cred > entry->cred)
2123 n = n->rb_right;
2124 else
2125 return entry;
1da177e4 2126 }
1c3c07e9
TM
2127 return NULL;
2128}
2129
af22f94a 2130static int nfs_access_get_cached(struct inode *inode, struct rpc_cred *cred, struct nfs_access_entry *res)
1c3c07e9
TM
2131{
2132 struct nfs_inode *nfsi = NFS_I(inode);
2133 struct nfs_access_entry *cache;
2134 int err = -ENOENT;
2135
dc59250c 2136 spin_lock(&inode->i_lock);
1c3c07e9
TM
2137 if (nfsi->cache_validity & NFS_INO_INVALID_ACCESS)
2138 goto out_zap;
2139 cache = nfs_access_search_rbtree(inode, cred);
2140 if (cache == NULL)
2141 goto out;
b4d2314b 2142 if (!nfs_have_delegated_attributes(inode) &&
64672d55 2143 !time_in_range_open(jiffies, cache->jiffies, cache->jiffies + nfsi->attrtimeo))
1c3c07e9
TM
2144 goto out_stale;
2145 res->jiffies = cache->jiffies;
2146 res->cred = cache->cred;
2147 res->mask = cache->mask;
cfcea3e8 2148 list_move_tail(&cache->lru, &nfsi->access_cache_entry_lru);
1c3c07e9
TM
2149 err = 0;
2150out:
2151 spin_unlock(&inode->i_lock);
2152 return err;
2153out_stale:
2154 rb_erase(&cache->rb_node, &nfsi->access_cache);
cfcea3e8 2155 list_del(&cache->lru);
1c3c07e9
TM
2156 spin_unlock(&inode->i_lock);
2157 nfs_access_free_entry(cache);
2158 return -ENOENT;
2159out_zap:
1a81bb8a
TM
2160 spin_unlock(&inode->i_lock);
2161 nfs_access_zap_cache(inode);
1c3c07e9
TM
2162 return -ENOENT;
2163}
2164
2165static void nfs_access_add_rbtree(struct inode *inode, struct nfs_access_entry *set)
2166{
cfcea3e8
TM
2167 struct nfs_inode *nfsi = NFS_I(inode);
2168 struct rb_root *root_node = &nfsi->access_cache;
1c3c07e9
TM
2169 struct rb_node **p = &root_node->rb_node;
2170 struct rb_node *parent = NULL;
2171 struct nfs_access_entry *entry;
2172
2173 spin_lock(&inode->i_lock);
2174 while (*p != NULL) {
2175 parent = *p;
2176 entry = rb_entry(parent, struct nfs_access_entry, rb_node);
2177
2178 if (set->cred < entry->cred)
2179 p = &parent->rb_left;
2180 else if (set->cred > entry->cred)
2181 p = &parent->rb_right;
2182 else
2183 goto found;
2184 }
2185 rb_link_node(&set->rb_node, parent, p);
2186 rb_insert_color(&set->rb_node, root_node);
cfcea3e8 2187 list_add_tail(&set->lru, &nfsi->access_cache_entry_lru);
dc59250c 2188 spin_unlock(&inode->i_lock);
1c3c07e9
TM
2189 return;
2190found:
2191 rb_replace_node(parent, &set->rb_node, root_node);
cfcea3e8
TM
2192 list_add_tail(&set->lru, &nfsi->access_cache_entry_lru);
2193 list_del(&entry->lru);
1c3c07e9
TM
2194 spin_unlock(&inode->i_lock);
2195 nfs_access_free_entry(entry);
2196}
2197
af22f94a 2198static void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set)
1c3c07e9
TM
2199{
2200 struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_KERNEL);
2201 if (cache == NULL)
2202 return;
2203 RB_CLEAR_NODE(&cache->rb_node);
1da177e4 2204 cache->jiffies = set->jiffies;
1c3c07e9 2205 cache->cred = get_rpccred(set->cred);
1da177e4 2206 cache->mask = set->mask;
1c3c07e9
TM
2207
2208 nfs_access_add_rbtree(inode, cache);
cfcea3e8
TM
2209
2210 /* Update accounting */
2211 smp_mb__before_atomic_inc();
2212 atomic_long_inc(&nfs_access_nr_entries);
2213 smp_mb__after_atomic_inc();
2214
2215 /* Add inode to global LRU list */
1a81bb8a 2216 if (!test_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags)) {
cfcea3e8 2217 spin_lock(&nfs_access_lru_lock);
1a81bb8a
TM
2218 if (!test_and_set_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags))
2219 list_add_tail(&NFS_I(inode)->access_cache_inode_lru,
2220 &nfs_access_lru_list);
cfcea3e8
TM
2221 spin_unlock(&nfs_access_lru_lock);
2222 }
1da177e4
LT
2223}
2224
2225static int nfs_do_access(struct inode *inode, struct rpc_cred *cred, int mask)
2226{
2227 struct nfs_access_entry cache;
2228 int status;
2229
2230 status = nfs_access_get_cached(inode, cred, &cache);
2231 if (status == 0)
2232 goto out;
2233
2234 /* Be clever: ask server to check for all possible rights */
2235 cache.mask = MAY_EXEC | MAY_WRITE | MAY_READ;
2236 cache.cred = cred;
2237 cache.jiffies = jiffies;
2238 status = NFS_PROTO(inode)->access(inode, &cache);
a71ee337
SJ
2239 if (status != 0) {
2240 if (status == -ESTALE) {
2241 nfs_zap_caches(inode);
2242 if (!S_ISDIR(inode->i_mode))
2243 set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
2244 }
1da177e4 2245 return status;
a71ee337 2246 }
1da177e4
LT
2247 nfs_access_add_cache(inode, &cache);
2248out:
e6305c43 2249 if ((mask & ~cache.mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) == 0)
1da177e4
LT
2250 return 0;
2251 return -EACCES;
2252}
2253
af22f94a
TM
2254static int nfs_open_permission_mask(int openflags)
2255{
2256 int mask = 0;
2257
2258 if (openflags & FMODE_READ)
2259 mask |= MAY_READ;
2260 if (openflags & FMODE_WRITE)
2261 mask |= MAY_WRITE;
2262 if (openflags & FMODE_EXEC)
2263 mask |= MAY_EXEC;
2264 return mask;
2265}
2266
2267int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags)
2268{
2269 return nfs_do_access(inode, cred, nfs_open_permission_mask(openflags));
2270}
2271
10556cb2 2272int nfs_permission(struct inode *inode, int mask)
1da177e4
LT
2273{
2274 struct rpc_cred *cred;
2275 int res = 0;
2276
10556cb2 2277 if (mask & MAY_NOT_BLOCK)
b74c79e9
NP
2278 return -ECHILD;
2279
91d5b470
CL
2280 nfs_inc_stats(inode, NFSIOS_VFSACCESS);
2281
e6305c43 2282 if ((mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) == 0)
1da177e4
LT
2283 goto out;
2284 /* Is this sys_access() ? */
9cfcac81 2285 if (mask & (MAY_ACCESS | MAY_CHDIR))
1da177e4
LT
2286 goto force_lookup;
2287
2288 switch (inode->i_mode & S_IFMT) {
2289 case S_IFLNK:
2290 goto out;
2291 case S_IFREG:
2292 /* NFSv4 has atomic_open... */
2293 if (nfs_server_capable(inode, NFS_CAP_ATOMIC_OPEN)
7ee2cb7f
FF
2294 && (mask & MAY_OPEN)
2295 && !(mask & MAY_EXEC))
1da177e4
LT
2296 goto out;
2297 break;
2298 case S_IFDIR:
2299 /*
2300 * Optimize away all write operations, since the server
2301 * will check permissions when we perform the op.
2302 */
2303 if ((mask & MAY_WRITE) && !(mask & MAY_READ))
2304 goto out;
2305 }
2306
2307force_lookup:
1da177e4
LT
2308 if (!NFS_PROTO(inode)->access)
2309 goto out_notsup;
2310
98a8e323 2311 cred = rpc_lookup_cred();
1da177e4
LT
2312 if (!IS_ERR(cred)) {
2313 res = nfs_do_access(inode, cred, mask);
2314 put_rpccred(cred);
2315 } else
2316 res = PTR_ERR(cred);
1da177e4 2317out:
f696a365
MS
2318 if (!res && (mask & MAY_EXEC) && !execute_ok(inode))
2319 res = -EACCES;
2320
1e7cb3dc
CL
2321 dfprintk(VFS, "NFS: permission(%s/%ld), mask=0x%x, res=%d\n",
2322 inode->i_sb->s_id, inode->i_ino, mask, res);
1da177e4
LT
2323 return res;
2324out_notsup:
2325 res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
2326 if (res == 0)
2830ba7f 2327 res = generic_permission(inode, mask);
1e7cb3dc 2328 goto out;
1da177e4
LT
2329}
2330
2331/*
2332 * Local variables:
2333 * version-control: t
2334 * kept-new-versions: 5
2335 * End:
2336 */