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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{
1348 struct path path = {
1349 .mnt = nd->path.mnt,
1350 .dentry = dentry,
1351 };
1352 struct nfs_open_context *ctx;
1353 struct rpc_cred *cred;
1354 fmode_t fmode = nd->intent.open.flags & (FMODE_READ | FMODE_WRITE | FMODE_EXEC);
1355
1356 cred = rpc_lookup_cred();
1357 if (IS_ERR(cred))
1358 return ERR_CAST(cred);
1359 ctx = alloc_nfs_open_context(&path, cred, fmode);
1360 put_rpccred(cred);
1361 if (ctx == NULL)
1362 return ERR_PTR(-ENOMEM);
1363 return ctx;
1364}
1365
1366static int do_open(struct inode *inode, struct file *filp)
1367{
1368 nfs_fscache_set_inode_cookie(inode, filp);
1369 return 0;
1370}
1371
1372static int nfs_intent_set_file(struct nameidata *nd, struct nfs_open_context *ctx)
1373{
1374 struct file *filp;
1375 int ret = 0;
1376
1377 /* If the open_intent is for execute, we have an extra check to make */
1378 if (ctx->mode & FMODE_EXEC) {
1379 ret = nfs_may_open(ctx->path.dentry->d_inode,
1380 ctx->cred,
1381 nd->intent.open.flags);
1382 if (ret < 0)
1383 goto out;
1384 }
1385 filp = lookup_instantiate_filp(nd, ctx->path.dentry, do_open);
1386 if (IS_ERR(filp))
1387 ret = PTR_ERR(filp);
1388 else
1389 nfs_file_set_open_context(filp, ctx);
1390out:
1391 put_nfs_open_context(ctx);
1392 return ret;
1393}
1394
1da177e4
LT
1395static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
1396{
cd9a1c0e
TM
1397 struct nfs_open_context *ctx;
1398 struct iattr attr;
1da177e4 1399 struct dentry *res = NULL;
f46e0bd3 1400 struct inode *inode;
cd9a1c0e 1401 int open_flags;
898f635c 1402 int err;
1da177e4 1403
1e7cb3dc
CL
1404 dfprintk(VFS, "NFS: atomic_lookup(%s/%ld), %s\n",
1405 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1406
1da177e4 1407 /* Check that we are indeed trying to open this file */
5584c306 1408 if (!is_atomic_open(nd))
1da177e4
LT
1409 goto no_open;
1410
1411 if (dentry->d_name.len > NFS_SERVER(dir)->namelen) {
1412 res = ERR_PTR(-ENAMETOOLONG);
1413 goto out;
1414 }
1da177e4 1415
d4d9cdcb
TM
1416 /* Let vfs_create() deal with O_EXCL. Instantiate, but don't hash
1417 * the dentry. */
3516586a 1418 if (nd->flags & LOOKUP_EXCL) {
d4d9cdcb 1419 d_instantiate(dentry, NULL);
02a913a7
TM
1420 goto out;
1421 }
1da177e4 1422
cd9a1c0e
TM
1423 ctx = nameidata_to_nfs_open_context(dentry, nd);
1424 res = ERR_CAST(ctx);
1425 if (IS_ERR(ctx))
1426 goto out;
1427
1428 open_flags = nd->intent.open.flags;
1429 if (nd->flags & LOOKUP_CREATE) {
1430 attr.ia_mode = nd->intent.open.create_mode;
1431 attr.ia_valid = ATTR_MODE;
a8a5da99 1432 attr.ia_mode &= ~current_umask();
cd9a1c0e 1433 } else {
898f635c 1434 open_flags &= ~(O_EXCL | O_CREAT);
cd9a1c0e 1435 attr.ia_valid = 0;
cd9a1c0e
TM
1436 }
1437
1da177e4 1438 /* Open the file on the server */
f46e0bd3 1439 nfs_block_sillyrename(dentry->d_parent);
2b484297 1440 inode = NFS_PROTO(dir)->open_context(dir, ctx, open_flags, &attr);
f46e0bd3
TM
1441 if (IS_ERR(inode)) {
1442 nfs_unblock_sillyrename(dentry->d_parent);
cd9a1c0e 1443 put_nfs_open_context(ctx);
f46e0bd3 1444 switch (PTR_ERR(inode)) {
1da177e4
LT
1445 /* Make a negative dentry */
1446 case -ENOENT:
f46e0bd3 1447 d_add(dentry, NULL);
02a913a7
TM
1448 res = NULL;
1449 goto out;
1da177e4 1450 /* This turned out not to be a regular file */
6f926b5b
TM
1451 case -ENOTDIR:
1452 goto no_open;
1da177e4
LT
1453 case -ELOOP:
1454 if (!(nd->intent.open.flags & O_NOFOLLOW))
1455 goto no_open;
23ebbd9a 1456 /* case -EISDIR: */
1da177e4
LT
1457 /* case -EINVAL: */
1458 default:
f46e0bd3 1459 res = ERR_CAST(inode);
1da177e4
LT
1460 goto out;
1461 }
cd9a1c0e 1462 }
f46e0bd3 1463 res = d_add_unique(dentry, inode);
898f635c 1464 nfs_unblock_sillyrename(dentry->d_parent);
f46e0bd3
TM
1465 if (res != NULL) {
1466 dput(ctx->path.dentry);
1467 ctx->path.dentry = dget(res);
1da177e4 1468 dentry = res;
f46e0bd3 1469 }
898f635c
TM
1470 err = nfs_intent_set_file(nd, ctx);
1471 if (err < 0) {
1472 if (res != NULL)
1473 dput(res);
1474 return ERR_PTR(err);
1475 }
1da177e4 1476out:
f46e0bd3 1477 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1da177e4
LT
1478 return res;
1479no_open:
1480 return nfs_lookup(dir, dentry, nd);
1481}
1482
1483static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
1484{
1485 struct dentry *parent = NULL;
657e94b6 1486 struct inode *inode;
1da177e4 1487 struct inode *dir;
b8d4cadd 1488 struct nfs_open_context *ctx;
1da177e4
LT
1489 int openflags, ret = 0;
1490
657e94b6
NP
1491 if (nd->flags & LOOKUP_RCU)
1492 return -ECHILD;
1493
1494 inode = dentry->d_inode;
1f063d2c 1495 if (!is_atomic_open(nd) || d_mountpoint(dentry))
5584c306 1496 goto no_open;
2b484297 1497
1da177e4
LT
1498 parent = dget_parent(dentry);
1499 dir = parent->d_inode;
2b484297 1500
1da177e4
LT
1501 /* We can't create new files in nfs_open_revalidate(), so we
1502 * optimize away revalidation of negative dentries.
1503 */
216d5d06
TM
1504 if (inode == NULL) {
1505 if (!nfs_neg_need_reval(dir, dentry, nd))
1506 ret = 1;
1da177e4 1507 goto out;
216d5d06
TM
1508 }
1509
1da177e4
LT
1510 /* NFS only supports OPEN on regular files */
1511 if (!S_ISREG(inode->i_mode))
5584c306 1512 goto no_open_dput;
1da177e4
LT
1513 openflags = nd->intent.open.flags;
1514 /* We cannot do exclusive creation on a positive dentry */
1515 if ((openflags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL))
5584c306 1516 goto no_open_dput;
1da177e4 1517 /* We can't create new files, or truncate existing ones here */
0a377cff 1518 openflags &= ~(O_CREAT|O_EXCL|O_TRUNC);
1da177e4 1519
b8d4cadd
TM
1520 ctx = nameidata_to_nfs_open_context(dentry, nd);
1521 ret = PTR_ERR(ctx);
1522 if (IS_ERR(ctx))
1523 goto out;
1da177e4 1524 /*
1b1dcc1b 1525 * Note: we're not holding inode->i_mutex and so may be racing with
1da177e4
LT
1526 * operations that change the directory. We therefore save the
1527 * change attribute *before* we do the RPC call.
1528 */
2b484297 1529 inode = NFS_PROTO(dir)->open_context(dir, ctx, openflags, NULL);
535918f1
TM
1530 if (IS_ERR(inode)) {
1531 ret = PTR_ERR(inode);
1532 switch (ret) {
1533 case -EPERM:
1534 case -EACCES:
1535 case -EDQUOT:
1536 case -ENOSPC:
1537 case -EROFS:
1538 goto out_put_ctx;
1539 default:
1540 goto out_drop;
1541 }
1542 }
1543 iput(inode);
898f635c 1544 if (inode != dentry->d_inode)
535918f1 1545 goto out_drop;
898f635c
TM
1546
1547 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1548 ret = nfs_intent_set_file(nd, ctx);
1549 if (ret >= 0)
1550 ret = 1;
1da177e4
LT
1551out:
1552 dput(parent);
1da177e4 1553 return ret;
535918f1
TM
1554out_drop:
1555 d_drop(dentry);
1556 ret = 0;
1557out_put_ctx:
1558 put_nfs_open_context(ctx);
1559 goto out;
1560
5584c306 1561no_open_dput:
1da177e4 1562 dput(parent);
5584c306 1563no_open:
1da177e4
LT
1564 return nfs_lookup_revalidate(dentry, nd);
1565}
c0204fd2
TM
1566
1567static int nfs_open_create(struct inode *dir, struct dentry *dentry, int mode,
1568 struct nameidata *nd)
1569{
1570 struct nfs_open_context *ctx = NULL;
1571 struct iattr attr;
1572 int error;
1573 int open_flags = 0;
1574
1575 dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
1576 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1577
1578 attr.ia_mode = mode;
1579 attr.ia_valid = ATTR_MODE;
1580
1581 if ((nd->flags & LOOKUP_CREATE) != 0) {
1582 open_flags = nd->intent.open.flags;
1583
1584 ctx = nameidata_to_nfs_open_context(dentry, nd);
1585 error = PTR_ERR(ctx);
1586 if (IS_ERR(ctx))
898f635c 1587 goto out_err_drop;
c0204fd2
TM
1588 }
1589
1590 error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, ctx);
1591 if (error != 0)
1592 goto out_put_ctx;
898f635c
TM
1593 if (ctx != NULL) {
1594 error = nfs_intent_set_file(nd, ctx);
1595 if (error < 0)
1596 goto out_err;
1597 }
c0204fd2
TM
1598 return 0;
1599out_put_ctx:
1600 if (ctx != NULL)
1601 put_nfs_open_context(ctx);
898f635c 1602out_err_drop:
c0204fd2 1603 d_drop(dentry);
898f635c 1604out_err:
c0204fd2
TM
1605 return error;
1606}
1607
1da177e4
LT
1608#endif /* CONFIG_NFSV4 */
1609
1da177e4
LT
1610/*
1611 * Code common to create, mkdir, and mknod.
1612 */
1613int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fhandle,
1614 struct nfs_fattr *fattr)
1615{
fab728e1
TM
1616 struct dentry *parent = dget_parent(dentry);
1617 struct inode *dir = parent->d_inode;
1da177e4
LT
1618 struct inode *inode;
1619 int error = -EACCES;
1620
fab728e1
TM
1621 d_drop(dentry);
1622
1da177e4
LT
1623 /* We may have been initialized further down */
1624 if (dentry->d_inode)
fab728e1 1625 goto out;
1da177e4 1626 if (fhandle->size == 0) {
7c513058 1627 error = NFS_PROTO(dir)->lookup(NFS_SERVER(dir)->client, dir, &dentry->d_name, fhandle, fattr);
1da177e4 1628 if (error)
fab728e1 1629 goto out_error;
1da177e4 1630 }
5724ab37 1631 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1da177e4
LT
1632 if (!(fattr->valid & NFS_ATTR_FATTR)) {
1633 struct nfs_server *server = NFS_SB(dentry->d_sb);
8fa5c000 1634 error = server->nfs_client->rpc_ops->getattr(server, fhandle, fattr);
1da177e4 1635 if (error < 0)
fab728e1 1636 goto out_error;
1da177e4 1637 }
1da177e4 1638 inode = nfs_fhget(dentry->d_sb, fhandle, fattr);
03f28e3a
TM
1639 error = PTR_ERR(inode);
1640 if (IS_ERR(inode))
fab728e1
TM
1641 goto out_error;
1642 d_add(dentry, inode);
1643out:
1644 dput(parent);
1da177e4 1645 return 0;
fab728e1
TM
1646out_error:
1647 nfs_mark_for_revalidate(dir);
1648 dput(parent);
1649 return error;
1da177e4
LT
1650}
1651
1652/*
1653 * Following a failed create operation, we drop the dentry rather
1654 * than retain a negative dentry. This avoids a problem in the event
1655 * that the operation succeeded on the server, but an error in the
1656 * reply path made it appear to have failed.
1657 */
1658static int nfs_create(struct inode *dir, struct dentry *dentry, int mode,
1659 struct nameidata *nd)
1660{
1661 struct iattr attr;
1662 int error;
8a0eebf6 1663 int open_flags = 0;
1da177e4 1664
1e7cb3dc
CL
1665 dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
1666 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1da177e4
LT
1667
1668 attr.ia_mode = mode;
1669 attr.ia_valid = ATTR_MODE;
1670
8a0eebf6
TM
1671 if ((nd->flags & LOOKUP_CREATE) != 0)
1672 open_flags = nd->intent.open.flags;
1673
1674 error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, NULL);
1da177e4
LT
1675 if (error != 0)
1676 goto out_err;
1da177e4
LT
1677 return 0;
1678out_err:
1da177e4
LT
1679 d_drop(dentry);
1680 return error;
1681}
1682
1683/*
1684 * See comments for nfs_proc_create regarding failed operations.
1685 */
1686static int
1687nfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
1688{
1689 struct iattr attr;
1690 int status;
1691
1e7cb3dc
CL
1692 dfprintk(VFS, "NFS: mknod(%s/%ld), %s\n",
1693 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1da177e4
LT
1694
1695 if (!new_valid_dev(rdev))
1696 return -EINVAL;
1697
1698 attr.ia_mode = mode;
1699 attr.ia_valid = ATTR_MODE;
1700
1da177e4 1701 status = NFS_PROTO(dir)->mknod(dir, dentry, &attr, rdev);
1da177e4
LT
1702 if (status != 0)
1703 goto out_err;
1da177e4
LT
1704 return 0;
1705out_err:
1da177e4
LT
1706 d_drop(dentry);
1707 return status;
1708}
1709
1710/*
1711 * See comments for nfs_proc_create regarding failed operations.
1712 */
1713static int nfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
1714{
1715 struct iattr attr;
1716 int error;
1717
1e7cb3dc
CL
1718 dfprintk(VFS, "NFS: mkdir(%s/%ld), %s\n",
1719 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1da177e4
LT
1720
1721 attr.ia_valid = ATTR_MODE;
1722 attr.ia_mode = mode | S_IFDIR;
1723
1da177e4 1724 error = NFS_PROTO(dir)->mkdir(dir, dentry, &attr);
1da177e4
LT
1725 if (error != 0)
1726 goto out_err;
1da177e4
LT
1727 return 0;
1728out_err:
1729 d_drop(dentry);
1da177e4
LT
1730 return error;
1731}
1732
d45b9d8b
TM
1733static void nfs_dentry_handle_enoent(struct dentry *dentry)
1734{
1735 if (dentry->d_inode != NULL && !d_unhashed(dentry))
1736 d_delete(dentry);
1737}
1738
1da177e4
LT
1739static int nfs_rmdir(struct inode *dir, struct dentry *dentry)
1740{
1741 int error;
1742
1e7cb3dc
CL
1743 dfprintk(VFS, "NFS: rmdir(%s/%ld), %s\n",
1744 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1da177e4 1745
1da177e4
LT
1746 error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name);
1747 /* Ensure the VFS deletes this inode */
1748 if (error == 0 && dentry->d_inode != NULL)
ce71ec36 1749 clear_nlink(dentry->d_inode);
d45b9d8b
TM
1750 else if (error == -ENOENT)
1751 nfs_dentry_handle_enoent(dentry);
1da177e4
LT
1752
1753 return error;
1754}
1755
1da177e4
LT
1756/*
1757 * Remove a file after making sure there are no pending writes,
1758 * and after checking that the file has only one user.
1759 *
1760 * We invalidate the attribute cache and free the inode prior to the operation
1761 * to avoid possible races if the server reuses the inode.
1762 */
1763static int nfs_safe_remove(struct dentry *dentry)
1764{
1765 struct inode *dir = dentry->d_parent->d_inode;
1766 struct inode *inode = dentry->d_inode;
1767 int error = -EBUSY;
1768
1769 dfprintk(VFS, "NFS: safe_remove(%s/%s)\n",
1770 dentry->d_parent->d_name.name, dentry->d_name.name);
1771
1772 /* If the dentry was sillyrenamed, we simply call d_delete() */
1773 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
1774 error = 0;
1775 goto out;
1776 }
1777
1da177e4 1778 if (inode != NULL) {
cae7a073 1779 nfs_inode_return_delegation(inode);
1da177e4
LT
1780 error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
1781 /* The VFS may want to delete this inode */
1782 if (error == 0)
1b83d707 1783 nfs_drop_nlink(inode);
5ba7cc48 1784 nfs_mark_for_revalidate(inode);
1da177e4
LT
1785 } else
1786 error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
d45b9d8b
TM
1787 if (error == -ENOENT)
1788 nfs_dentry_handle_enoent(dentry);
1da177e4
LT
1789out:
1790 return error;
1791}
1792
1793/* We do silly rename. In case sillyrename() returns -EBUSY, the inode
1794 * belongs to an active ".nfs..." file and we return -EBUSY.
1795 *
1796 * If sillyrename() returns 0, we do nothing, otherwise we unlink.
1797 */
1798static int nfs_unlink(struct inode *dir, struct dentry *dentry)
1799{
1800 int error;
1801 int need_rehash = 0;
1802
1803 dfprintk(VFS, "NFS: unlink(%s/%ld, %s)\n", dir->i_sb->s_id,
1804 dir->i_ino, dentry->d_name.name);
1805
1da177e4 1806 spin_lock(&dentry->d_lock);
b7ab39f6 1807 if (dentry->d_count > 1) {
1da177e4 1808 spin_unlock(&dentry->d_lock);
ccfeb506
TM
1809 /* Start asynchronous writeout of the inode */
1810 write_inode_now(dentry->d_inode, 0);
1da177e4 1811 error = nfs_sillyrename(dir, dentry);
1da177e4
LT
1812 return error;
1813 }
1814 if (!d_unhashed(dentry)) {
1815 __d_drop(dentry);
1816 need_rehash = 1;
1817 }
1818 spin_unlock(&dentry->d_lock);
1da177e4 1819 error = nfs_safe_remove(dentry);
d45b9d8b 1820 if (!error || error == -ENOENT) {
1da177e4
LT
1821 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1822 } else if (need_rehash)
1823 d_rehash(dentry);
1da177e4
LT
1824 return error;
1825}
1826
873101b3
CL
1827/*
1828 * To create a symbolic link, most file systems instantiate a new inode,
1829 * add a page to it containing the path, then write it out to the disk
1830 * using prepare_write/commit_write.
1831 *
1832 * Unfortunately the NFS client can't create the in-core inode first
1833 * because it needs a file handle to create an in-core inode (see
1834 * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the
1835 * symlink request has completed on the server.
1836 *
1837 * So instead we allocate a raw page, copy the symname into it, then do
1838 * the SYMLINK request with the page as the buffer. If it succeeds, we
1839 * now have a new file handle and can instantiate an in-core NFS inode
1840 * and move the raw page into its mapping.
1841 */
1842static int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
1da177e4 1843{
873101b3
CL
1844 struct pagevec lru_pvec;
1845 struct page *page;
1846 char *kaddr;
1da177e4 1847 struct iattr attr;
873101b3 1848 unsigned int pathlen = strlen(symname);
1da177e4
LT
1849 int error;
1850
1851 dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s)\n", dir->i_sb->s_id,
1852 dir->i_ino, dentry->d_name.name, symname);
1853
873101b3
CL
1854 if (pathlen > PAGE_SIZE)
1855 return -ENAMETOOLONG;
1da177e4 1856
873101b3
CL
1857 attr.ia_mode = S_IFLNK | S_IRWXUGO;
1858 attr.ia_valid = ATTR_MODE;
1da177e4 1859
83d93f22 1860 page = alloc_page(GFP_HIGHUSER);
76566991 1861 if (!page)
873101b3 1862 return -ENOMEM;
873101b3
CL
1863
1864 kaddr = kmap_atomic(page, KM_USER0);
1865 memcpy(kaddr, symname, pathlen);
1866 if (pathlen < PAGE_SIZE)
1867 memset(kaddr + pathlen, 0, PAGE_SIZE - pathlen);
1868 kunmap_atomic(kaddr, KM_USER0);
1869
94a6d753 1870 error = NFS_PROTO(dir)->symlink(dir, dentry, page, pathlen, &attr);
873101b3
CL
1871 if (error != 0) {
1872 dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s) error %d\n",
1873 dir->i_sb->s_id, dir->i_ino,
1874 dentry->d_name.name, symname, error);
1da177e4 1875 d_drop(dentry);
873101b3 1876 __free_page(page);
873101b3
CL
1877 return error;
1878 }
1879
1880 /*
1881 * No big deal if we can't add this page to the page cache here.
1882 * READLINK will get the missing page from the server if needed.
1883 */
1884 pagevec_init(&lru_pvec, 0);
1885 if (!add_to_page_cache(page, dentry->d_inode->i_mapping, 0,
1886 GFP_KERNEL)) {
39cf8a13 1887 pagevec_add(&lru_pvec, page);
4f98a2fe 1888 pagevec_lru_add_file(&lru_pvec);
873101b3
CL
1889 SetPageUptodate(page);
1890 unlock_page(page);
1891 } else
1892 __free_page(page);
1893
873101b3 1894 return 0;
1da177e4
LT
1895}
1896
1897static int
1898nfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
1899{
1900 struct inode *inode = old_dentry->d_inode;
1901 int error;
1902
1903 dfprintk(VFS, "NFS: link(%s/%s -> %s/%s)\n",
1904 old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
1905 dentry->d_parent->d_name.name, dentry->d_name.name);
1906
9a3936aa
TM
1907 nfs_inode_return_delegation(inode);
1908
9697d234 1909 d_drop(dentry);
1da177e4 1910 error = NFS_PROTO(dir)->link(inode, dir, &dentry->d_name);
cf809556 1911 if (error == 0) {
7de9c6ee 1912 ihold(inode);
9697d234 1913 d_add(dentry, inode);
cf809556 1914 }
1da177e4
LT
1915 return error;
1916}
1917
1918/*
1919 * RENAME
1920 * FIXME: Some nfsds, like the Linux user space nfsd, may generate a
1921 * different file handle for the same inode after a rename (e.g. when
1922 * moving to a different directory). A fail-safe method to do so would
1923 * be to look up old_dir/old_name, create a link to new_dir/new_name and
1924 * rename the old file using the sillyrename stuff. This way, the original
1925 * file in old_dir will go away when the last process iput()s the inode.
1926 *
1927 * FIXED.
1928 *
1929 * It actually works quite well. One needs to have the possibility for
1930 * at least one ".nfs..." file in each directory the file ever gets
1931 * moved or linked to which happens automagically with the new
1932 * implementation that only depends on the dcache stuff instead of
1933 * using the inode layer
1934 *
1935 * Unfortunately, things are a little more complicated than indicated
1936 * above. For a cross-directory move, we want to make sure we can get
1937 * rid of the old inode after the operation. This means there must be
1938 * no pending writes (if it's a file), and the use count must be 1.
1939 * If these conditions are met, we can drop the dentries before doing
1940 * the rename.
1941 */
1942static int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
1943 struct inode *new_dir, struct dentry *new_dentry)
1944{
1945 struct inode *old_inode = old_dentry->d_inode;
1946 struct inode *new_inode = new_dentry->d_inode;
1947 struct dentry *dentry = NULL, *rehash = NULL;
1948 int error = -EBUSY;
1949
1da177e4
LT
1950 dfprintk(VFS, "NFS: rename(%s/%s -> %s/%s, ct=%d)\n",
1951 old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
1952 new_dentry->d_parent->d_name.name, new_dentry->d_name.name,
b7ab39f6 1953 new_dentry->d_count);
1da177e4
LT
1954
1955 /*
28f79a1a
MS
1956 * For non-directories, check whether the target is busy and if so,
1957 * make a copy of the dentry and then do a silly-rename. If the
1958 * silly-rename succeeds, the copied dentry is hashed and becomes
1959 * the new target.
1da177e4 1960 */
27226104
MS
1961 if (new_inode && !S_ISDIR(new_inode->i_mode)) {
1962 /*
1963 * To prevent any new references to the target during the
1964 * rename, we unhash the dentry in advance.
1965 */
1966 if (!d_unhashed(new_dentry)) {
1967 d_drop(new_dentry);
1968 rehash = new_dentry;
1969 }
1da177e4 1970
b7ab39f6 1971 if (new_dentry->d_count > 2) {
27226104
MS
1972 int err;
1973
1974 /* copy the target dentry's name */
1975 dentry = d_alloc(new_dentry->d_parent,
1976 &new_dentry->d_name);
1977 if (!dentry)
1978 goto out;
1979
1980 /* silly-rename the existing target ... */
1981 err = nfs_sillyrename(new_dir, new_dentry);
24e93025 1982 if (err)
27226104 1983 goto out;
24e93025
MS
1984
1985 new_dentry = dentry;
56335936 1986 rehash = NULL;
24e93025 1987 new_inode = NULL;
27226104 1988 }
b1e4adf4 1989 }
1da177e4 1990
cae7a073 1991 nfs_inode_return_delegation(old_inode);
b1e4adf4 1992 if (new_inode != NULL)
24174119 1993 nfs_inode_return_delegation(new_inode);
1da177e4 1994
1da177e4
LT
1995 error = NFS_PROTO(old_dir)->rename(old_dir, &old_dentry->d_name,
1996 new_dir, &new_dentry->d_name);
5ba7cc48 1997 nfs_mark_for_revalidate(old_inode);
1da177e4
LT
1998out:
1999 if (rehash)
2000 d_rehash(rehash);
2001 if (!error) {
b1e4adf4
TM
2002 if (new_inode != NULL)
2003 nfs_drop_nlink(new_inode);
349457cc 2004 d_move(old_dentry, new_dentry);
8fb559f8
CL
2005 nfs_set_verifier(new_dentry,
2006 nfs_save_change_attribute(new_dir));
d45b9d8b
TM
2007 } else if (error == -ENOENT)
2008 nfs_dentry_handle_enoent(old_dentry);
1da177e4
LT
2009
2010 /* new dentry created? */
2011 if (dentry)
2012 dput(dentry);
1da177e4
LT
2013 return error;
2014}
2015
cfcea3e8
TM
2016static DEFINE_SPINLOCK(nfs_access_lru_lock);
2017static LIST_HEAD(nfs_access_lru_list);
2018static atomic_long_t nfs_access_nr_entries;
2019
1c3c07e9
TM
2020static void nfs_access_free_entry(struct nfs_access_entry *entry)
2021{
2022 put_rpccred(entry->cred);
2023 kfree(entry);
cfcea3e8
TM
2024 smp_mb__before_atomic_dec();
2025 atomic_long_dec(&nfs_access_nr_entries);
2026 smp_mb__after_atomic_dec();
1c3c07e9
TM
2027}
2028
1a81bb8a
TM
2029static void nfs_access_free_list(struct list_head *head)
2030{
2031 struct nfs_access_entry *cache;
2032
2033 while (!list_empty(head)) {
2034 cache = list_entry(head->next, struct nfs_access_entry, lru);
2035 list_del(&cache->lru);
2036 nfs_access_free_entry(cache);
2037 }
2038}
2039
1495f230
YH
2040int nfs_access_cache_shrinker(struct shrinker *shrink,
2041 struct shrink_control *sc)
979df72e
TM
2042{
2043 LIST_HEAD(head);
aa510da5 2044 struct nfs_inode *nfsi, *next;
979df72e 2045 struct nfs_access_entry *cache;
1495f230
YH
2046 int nr_to_scan = sc->nr_to_scan;
2047 gfp_t gfp_mask = sc->gfp_mask;
979df72e 2048
61d5eb29
TM
2049 if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
2050 return (nr_to_scan == 0) ? 0 : -1;
9c7e7e23 2051
a50f7951 2052 spin_lock(&nfs_access_lru_lock);
aa510da5 2053 list_for_each_entry_safe(nfsi, next, &nfs_access_lru_list, access_cache_inode_lru) {
979df72e
TM
2054 struct inode *inode;
2055
2056 if (nr_to_scan-- == 0)
2057 break;
9c7e7e23 2058 inode = &nfsi->vfs_inode;
979df72e
TM
2059 spin_lock(&inode->i_lock);
2060 if (list_empty(&nfsi->access_cache_entry_lru))
2061 goto remove_lru_entry;
2062 cache = list_entry(nfsi->access_cache_entry_lru.next,
2063 struct nfs_access_entry, lru);
2064 list_move(&cache->lru, &head);
2065 rb_erase(&cache->rb_node, &nfsi->access_cache);
2066 if (!list_empty(&nfsi->access_cache_entry_lru))
2067 list_move_tail(&nfsi->access_cache_inode_lru,
2068 &nfs_access_lru_list);
2069 else {
2070remove_lru_entry:
2071 list_del_init(&nfsi->access_cache_inode_lru);
9c7e7e23 2072 smp_mb__before_clear_bit();
979df72e 2073 clear_bit(NFS_INO_ACL_LRU_SET, &nfsi->flags);
9c7e7e23 2074 smp_mb__after_clear_bit();
979df72e 2075 }
59844a9b 2076 spin_unlock(&inode->i_lock);
979df72e
TM
2077 }
2078 spin_unlock(&nfs_access_lru_lock);
1a81bb8a 2079 nfs_access_free_list(&head);
979df72e
TM
2080 return (atomic_long_read(&nfs_access_nr_entries) / 100) * sysctl_vfs_cache_pressure;
2081}
2082
1a81bb8a 2083static void __nfs_access_zap_cache(struct nfs_inode *nfsi, struct list_head *head)
1da177e4 2084{
1c3c07e9 2085 struct rb_root *root_node = &nfsi->access_cache;
1a81bb8a 2086 struct rb_node *n;
1c3c07e9
TM
2087 struct nfs_access_entry *entry;
2088
2089 /* Unhook entries from the cache */
2090 while ((n = rb_first(root_node)) != NULL) {
2091 entry = rb_entry(n, struct nfs_access_entry, rb_node);
2092 rb_erase(n, root_node);
1a81bb8a 2093 list_move(&entry->lru, head);
1c3c07e9
TM
2094 }
2095 nfsi->cache_validity &= ~NFS_INO_INVALID_ACCESS;
1da177e4
LT
2096}
2097
1c3c07e9 2098void nfs_access_zap_cache(struct inode *inode)
1da177e4 2099{
1a81bb8a
TM
2100 LIST_HEAD(head);
2101
2102 if (test_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags) == 0)
2103 return;
cfcea3e8 2104 /* Remove from global LRU init */
1a81bb8a
TM
2105 spin_lock(&nfs_access_lru_lock);
2106 if (test_and_clear_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags))
cfcea3e8 2107 list_del_init(&NFS_I(inode)->access_cache_inode_lru);
cfcea3e8 2108
1c3c07e9 2109 spin_lock(&inode->i_lock);
1a81bb8a
TM
2110 __nfs_access_zap_cache(NFS_I(inode), &head);
2111 spin_unlock(&inode->i_lock);
2112 spin_unlock(&nfs_access_lru_lock);
2113 nfs_access_free_list(&head);
1c3c07e9 2114}
1da177e4 2115
1c3c07e9
TM
2116static struct nfs_access_entry *nfs_access_search_rbtree(struct inode *inode, struct rpc_cred *cred)
2117{
2118 struct rb_node *n = NFS_I(inode)->access_cache.rb_node;
2119 struct nfs_access_entry *entry;
2120
2121 while (n != NULL) {
2122 entry = rb_entry(n, struct nfs_access_entry, rb_node);
2123
2124 if (cred < entry->cred)
2125 n = n->rb_left;
2126 else if (cred > entry->cred)
2127 n = n->rb_right;
2128 else
2129 return entry;
1da177e4 2130 }
1c3c07e9
TM
2131 return NULL;
2132}
2133
af22f94a 2134static int nfs_access_get_cached(struct inode *inode, struct rpc_cred *cred, struct nfs_access_entry *res)
1c3c07e9
TM
2135{
2136 struct nfs_inode *nfsi = NFS_I(inode);
2137 struct nfs_access_entry *cache;
2138 int err = -ENOENT;
2139
dc59250c 2140 spin_lock(&inode->i_lock);
1c3c07e9
TM
2141 if (nfsi->cache_validity & NFS_INO_INVALID_ACCESS)
2142 goto out_zap;
2143 cache = nfs_access_search_rbtree(inode, cred);
2144 if (cache == NULL)
2145 goto out;
b4d2314b 2146 if (!nfs_have_delegated_attributes(inode) &&
64672d55 2147 !time_in_range_open(jiffies, cache->jiffies, cache->jiffies + nfsi->attrtimeo))
1c3c07e9
TM
2148 goto out_stale;
2149 res->jiffies = cache->jiffies;
2150 res->cred = cache->cred;
2151 res->mask = cache->mask;
cfcea3e8 2152 list_move_tail(&cache->lru, &nfsi->access_cache_entry_lru);
1c3c07e9
TM
2153 err = 0;
2154out:
2155 spin_unlock(&inode->i_lock);
2156 return err;
2157out_stale:
2158 rb_erase(&cache->rb_node, &nfsi->access_cache);
cfcea3e8 2159 list_del(&cache->lru);
1c3c07e9
TM
2160 spin_unlock(&inode->i_lock);
2161 nfs_access_free_entry(cache);
2162 return -ENOENT;
2163out_zap:
1a81bb8a
TM
2164 spin_unlock(&inode->i_lock);
2165 nfs_access_zap_cache(inode);
1c3c07e9
TM
2166 return -ENOENT;
2167}
2168
2169static void nfs_access_add_rbtree(struct inode *inode, struct nfs_access_entry *set)
2170{
cfcea3e8
TM
2171 struct nfs_inode *nfsi = NFS_I(inode);
2172 struct rb_root *root_node = &nfsi->access_cache;
1c3c07e9
TM
2173 struct rb_node **p = &root_node->rb_node;
2174 struct rb_node *parent = NULL;
2175 struct nfs_access_entry *entry;
2176
2177 spin_lock(&inode->i_lock);
2178 while (*p != NULL) {
2179 parent = *p;
2180 entry = rb_entry(parent, struct nfs_access_entry, rb_node);
2181
2182 if (set->cred < entry->cred)
2183 p = &parent->rb_left;
2184 else if (set->cred > entry->cred)
2185 p = &parent->rb_right;
2186 else
2187 goto found;
2188 }
2189 rb_link_node(&set->rb_node, parent, p);
2190 rb_insert_color(&set->rb_node, root_node);
cfcea3e8 2191 list_add_tail(&set->lru, &nfsi->access_cache_entry_lru);
dc59250c 2192 spin_unlock(&inode->i_lock);
1c3c07e9
TM
2193 return;
2194found:
2195 rb_replace_node(parent, &set->rb_node, root_node);
cfcea3e8
TM
2196 list_add_tail(&set->lru, &nfsi->access_cache_entry_lru);
2197 list_del(&entry->lru);
1c3c07e9
TM
2198 spin_unlock(&inode->i_lock);
2199 nfs_access_free_entry(entry);
2200}
2201
af22f94a 2202static void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set)
1c3c07e9
TM
2203{
2204 struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_KERNEL);
2205 if (cache == NULL)
2206 return;
2207 RB_CLEAR_NODE(&cache->rb_node);
1da177e4 2208 cache->jiffies = set->jiffies;
1c3c07e9 2209 cache->cred = get_rpccred(set->cred);
1da177e4 2210 cache->mask = set->mask;
1c3c07e9
TM
2211
2212 nfs_access_add_rbtree(inode, cache);
cfcea3e8
TM
2213
2214 /* Update accounting */
2215 smp_mb__before_atomic_inc();
2216 atomic_long_inc(&nfs_access_nr_entries);
2217 smp_mb__after_atomic_inc();
2218
2219 /* Add inode to global LRU list */
1a81bb8a 2220 if (!test_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags)) {
cfcea3e8 2221 spin_lock(&nfs_access_lru_lock);
1a81bb8a
TM
2222 if (!test_and_set_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags))
2223 list_add_tail(&NFS_I(inode)->access_cache_inode_lru,
2224 &nfs_access_lru_list);
cfcea3e8
TM
2225 spin_unlock(&nfs_access_lru_lock);
2226 }
1da177e4
LT
2227}
2228
2229static int nfs_do_access(struct inode *inode, struct rpc_cred *cred, int mask)
2230{
2231 struct nfs_access_entry cache;
2232 int status;
2233
2234 status = nfs_access_get_cached(inode, cred, &cache);
2235 if (status == 0)
2236 goto out;
2237
2238 /* Be clever: ask server to check for all possible rights */
2239 cache.mask = MAY_EXEC | MAY_WRITE | MAY_READ;
2240 cache.cred = cred;
2241 cache.jiffies = jiffies;
2242 status = NFS_PROTO(inode)->access(inode, &cache);
a71ee337
SJ
2243 if (status != 0) {
2244 if (status == -ESTALE) {
2245 nfs_zap_caches(inode);
2246 if (!S_ISDIR(inode->i_mode))
2247 set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
2248 }
1da177e4 2249 return status;
a71ee337 2250 }
1da177e4
LT
2251 nfs_access_add_cache(inode, &cache);
2252out:
e6305c43 2253 if ((mask & ~cache.mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) == 0)
1da177e4
LT
2254 return 0;
2255 return -EACCES;
2256}
2257
af22f94a
TM
2258static int nfs_open_permission_mask(int openflags)
2259{
2260 int mask = 0;
2261
2262 if (openflags & FMODE_READ)
2263 mask |= MAY_READ;
2264 if (openflags & FMODE_WRITE)
2265 mask |= MAY_WRITE;
2266 if (openflags & FMODE_EXEC)
2267 mask |= MAY_EXEC;
2268 return mask;
2269}
2270
2271int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags)
2272{
2273 return nfs_do_access(inode, cred, nfs_open_permission_mask(openflags));
2274}
2275
b74c79e9 2276int nfs_permission(struct inode *inode, int mask, unsigned int flags)
1da177e4
LT
2277{
2278 struct rpc_cred *cred;
2279 int res = 0;
2280
b74c79e9
NP
2281 if (flags & IPERM_FLAG_RCU)
2282 return -ECHILD;
2283
91d5b470
CL
2284 nfs_inc_stats(inode, NFSIOS_VFSACCESS);
2285
e6305c43 2286 if ((mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) == 0)
1da177e4
LT
2287 goto out;
2288 /* Is this sys_access() ? */
9cfcac81 2289 if (mask & (MAY_ACCESS | MAY_CHDIR))
1da177e4
LT
2290 goto force_lookup;
2291
2292 switch (inode->i_mode & S_IFMT) {
2293 case S_IFLNK:
2294 goto out;
2295 case S_IFREG:
2296 /* NFSv4 has atomic_open... */
2297 if (nfs_server_capable(inode, NFS_CAP_ATOMIC_OPEN)
7ee2cb7f
FF
2298 && (mask & MAY_OPEN)
2299 && !(mask & MAY_EXEC))
1da177e4
LT
2300 goto out;
2301 break;
2302 case S_IFDIR:
2303 /*
2304 * Optimize away all write operations, since the server
2305 * will check permissions when we perform the op.
2306 */
2307 if ((mask & MAY_WRITE) && !(mask & MAY_READ))
2308 goto out;
2309 }
2310
2311force_lookup:
1da177e4
LT
2312 if (!NFS_PROTO(inode)->access)
2313 goto out_notsup;
2314
98a8e323 2315 cred = rpc_lookup_cred();
1da177e4
LT
2316 if (!IS_ERR(cred)) {
2317 res = nfs_do_access(inode, cred, mask);
2318 put_rpccred(cred);
2319 } else
2320 res = PTR_ERR(cred);
1da177e4 2321out:
f696a365
MS
2322 if (!res && (mask & MAY_EXEC) && !execute_ok(inode))
2323 res = -EACCES;
2324
1e7cb3dc
CL
2325 dfprintk(VFS, "NFS: permission(%s/%ld), mask=0x%x, res=%d\n",
2326 inode->i_sb->s_id, inode->i_ino, mask, res);
1da177e4
LT
2327 return res;
2328out_notsup:
2329 res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
2330 if (res == 0)
178ea735 2331 res = generic_permission(inode, mask, flags);
1e7cb3dc 2332 goto out;
1da177e4
LT
2333}
2334
2335/*
2336 * Local variables:
2337 * version-control: t
2338 * kept-new-versions: 5
2339 * End:
2340 */