4 * Copyright (C) 1992 Rick Sladkey
6 * nfs directory handling functions
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
20 #include <linux/module.h>
21 #include <linux/time.h>
22 #include <linux/errno.h>
23 #include <linux/stat.h>
24 #include <linux/fcntl.h>
25 #include <linux/string.h>
26 #include <linux/kernel.h>
27 #include <linux/slab.h>
29 #include <linux/sunrpc/clnt.h>
30 #include <linux/nfs_fs.h>
31 #include <linux/nfs_mount.h>
32 #include <linux/pagemap.h>
33 #include <linux/pagevec.h>
34 #include <linux/namei.h>
35 #include <linux/mount.h>
36 #include <linux/swap.h>
37 #include <linux/sched.h>
38 #include <linux/kmemleak.h>
39 #include <linux/xattr.h>
41 #include "delegation.h"
48 /* #define NFS_DEBUG_VERBOSE 1 */
50 static int nfs_opendir(struct inode
*, struct file
*);
51 static int nfs_closedir(struct inode
*, struct file
*);
52 static int nfs_readdir(struct file
*, struct dir_context
*);
53 static int nfs_fsync_dir(struct file
*, loff_t
, loff_t
, int);
54 static loff_t
nfs_llseek_dir(struct file
*, loff_t
, int);
55 static void nfs_readdir_clear_array(struct page
*);
57 const struct file_operations nfs_dir_operations
= {
58 .llseek
= nfs_llseek_dir
,
59 .read
= generic_read_dir
,
60 .iterate
= nfs_readdir
,
62 .release
= nfs_closedir
,
63 .fsync
= nfs_fsync_dir
,
66 const struct address_space_operations nfs_dir_aops
= {
67 .freepage
= nfs_readdir_clear_array
,
70 static struct nfs_open_dir_context
*alloc_nfs_open_dir_context(struct inode
*dir
, struct rpc_cred
*cred
)
72 struct nfs_inode
*nfsi
= NFS_I(dir
);
73 struct nfs_open_dir_context
*ctx
;
74 ctx
= kmalloc(sizeof(*ctx
), GFP_KERNEL
);
77 ctx
->attr_gencount
= nfsi
->attr_gencount
;
80 ctx
->cred
= get_rpccred(cred
);
81 spin_lock(&dir
->i_lock
);
82 list_add(&ctx
->list
, &nfsi
->open_files
);
83 spin_unlock(&dir
->i_lock
);
86 return ERR_PTR(-ENOMEM
);
89 static void put_nfs_open_dir_context(struct inode
*dir
, struct nfs_open_dir_context
*ctx
)
91 spin_lock(&dir
->i_lock
);
93 spin_unlock(&dir
->i_lock
);
94 put_rpccred(ctx
->cred
);
102 nfs_opendir(struct inode
*inode
, struct file
*filp
)
105 struct nfs_open_dir_context
*ctx
;
106 struct rpc_cred
*cred
;
108 dfprintk(FILE, "NFS: open dir(%pD2)\n", filp
);
110 nfs_inc_stats(inode
, NFSIOS_VFSOPEN
);
112 cred
= rpc_lookup_cred();
114 return PTR_ERR(cred
);
115 ctx
= alloc_nfs_open_dir_context(inode
, cred
);
120 filp
->private_data
= ctx
;
121 if (filp
->f_path
.dentry
== filp
->f_path
.mnt
->mnt_root
) {
122 /* This is a mountpoint, so d_revalidate will never
123 * have been called, so we need to refresh the
124 * inode (for close-open consistency) ourselves.
126 __nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
134 nfs_closedir(struct inode
*inode
, struct file
*filp
)
136 put_nfs_open_dir_context(file_inode(filp
), filp
->private_data
);
140 struct nfs_cache_array_entry
{
144 unsigned char d_type
;
147 struct nfs_cache_array
{
151 struct nfs_cache_array_entry array
[0];
154 typedef int (*decode_dirent_t
)(struct xdr_stream
*, struct nfs_entry
*, bool);
158 struct dir_context
*ctx
;
159 unsigned long page_index
;
162 loff_t current_index
;
163 decode_dirent_t decode
;
165 unsigned long timestamp
;
166 unsigned long gencount
;
167 unsigned int cache_entry_index
;
170 } nfs_readdir_descriptor_t
;
173 * we are freeing strings created by nfs_add_to_readdir_array()
176 void nfs_readdir_clear_array(struct page
*page
)
178 struct nfs_cache_array
*array
;
181 array
= kmap_atomic(page
);
182 for (i
= 0; i
< array
->size
; i
++)
183 kfree(array
->array
[i
].string
.name
);
184 kunmap_atomic(array
);
188 * the caller is responsible for freeing qstr.name
189 * when called by nfs_readdir_add_to_array, the strings will be freed in
190 * nfs_clear_readdir_array()
193 int nfs_readdir_make_qstr(struct qstr
*string
, const char *name
, unsigned int len
)
196 string
->name
= kmemdup(name
, len
, GFP_KERNEL
);
197 if (string
->name
== NULL
)
200 * Avoid a kmemleak false positive. The pointer to the name is stored
201 * in a page cache page which kmemleak does not scan.
203 kmemleak_not_leak(string
->name
);
204 string
->hash
= full_name_hash(NULL
, name
, len
);
209 int nfs_readdir_add_to_array(struct nfs_entry
*entry
, struct page
*page
)
211 struct nfs_cache_array
*array
= kmap(page
);
212 struct nfs_cache_array_entry
*cache_entry
;
215 cache_entry
= &array
->array
[array
->size
];
217 /* Check that this entry lies within the page bounds */
219 if ((char *)&cache_entry
[1] - (char *)page_address(page
) > PAGE_SIZE
)
222 cache_entry
->cookie
= entry
->prev_cookie
;
223 cache_entry
->ino
= entry
->ino
;
224 cache_entry
->d_type
= entry
->d_type
;
225 ret
= nfs_readdir_make_qstr(&cache_entry
->string
, entry
->name
, entry
->len
);
228 array
->last_cookie
= entry
->cookie
;
231 array
->eof_index
= array
->size
;
238 int nfs_readdir_search_for_pos(struct nfs_cache_array
*array
, nfs_readdir_descriptor_t
*desc
)
240 loff_t diff
= desc
->ctx
->pos
- desc
->current_index
;
245 if (diff
>= array
->size
) {
246 if (array
->eof_index
>= 0)
251 index
= (unsigned int)diff
;
252 *desc
->dir_cookie
= array
->array
[index
].cookie
;
253 desc
->cache_entry_index
= index
;
261 nfs_readdir_inode_mapping_valid(struct nfs_inode
*nfsi
)
263 if (nfsi
->cache_validity
& (NFS_INO_INVALID_ATTR
|NFS_INO_INVALID_DATA
))
266 return !test_bit(NFS_INO_INVALIDATING
, &nfsi
->flags
);
270 int nfs_readdir_search_for_cookie(struct nfs_cache_array
*array
, nfs_readdir_descriptor_t
*desc
)
274 int status
= -EAGAIN
;
276 for (i
= 0; i
< array
->size
; i
++) {
277 if (array
->array
[i
].cookie
== *desc
->dir_cookie
) {
278 struct nfs_inode
*nfsi
= NFS_I(file_inode(desc
->file
));
279 struct nfs_open_dir_context
*ctx
= desc
->file
->private_data
;
281 new_pos
= desc
->current_index
+ i
;
282 if (ctx
->attr_gencount
!= nfsi
->attr_gencount
||
283 !nfs_readdir_inode_mapping_valid(nfsi
)) {
285 ctx
->attr_gencount
= nfsi
->attr_gencount
;
286 } else if (new_pos
< desc
->ctx
->pos
) {
288 && ctx
->dup_cookie
== *desc
->dir_cookie
) {
289 if (printk_ratelimit()) {
290 pr_notice("NFS: directory %pD2 contains a readdir loop."
291 "Please contact your server vendor. "
292 "The file: %.*s has duplicate cookie %llu\n",
293 desc
->file
, array
->array
[i
].string
.len
,
294 array
->array
[i
].string
.name
, *desc
->dir_cookie
);
299 ctx
->dup_cookie
= *desc
->dir_cookie
;
302 desc
->ctx
->pos
= new_pos
;
303 desc
->cache_entry_index
= i
;
307 if (array
->eof_index
>= 0) {
308 status
= -EBADCOOKIE
;
309 if (*desc
->dir_cookie
== array
->last_cookie
)
317 int nfs_readdir_search_array(nfs_readdir_descriptor_t
*desc
)
319 struct nfs_cache_array
*array
;
322 array
= kmap(desc
->page
);
324 if (*desc
->dir_cookie
== 0)
325 status
= nfs_readdir_search_for_pos(array
, desc
);
327 status
= nfs_readdir_search_for_cookie(array
, desc
);
329 if (status
== -EAGAIN
) {
330 desc
->last_cookie
= array
->last_cookie
;
331 desc
->current_index
+= array
->size
;
338 /* Fill a page with xdr information before transferring to the cache page */
340 int nfs_readdir_xdr_filler(struct page
**pages
, nfs_readdir_descriptor_t
*desc
,
341 struct nfs_entry
*entry
, struct file
*file
, struct inode
*inode
)
343 struct nfs_open_dir_context
*ctx
= file
->private_data
;
344 struct rpc_cred
*cred
= ctx
->cred
;
345 unsigned long timestamp
, gencount
;
350 gencount
= nfs_inc_attr_generation_counter();
351 error
= NFS_PROTO(inode
)->readdir(file_dentry(file
), cred
, entry
->cookie
, pages
,
352 NFS_SERVER(inode
)->dtsize
, desc
->plus
);
354 /* We requested READDIRPLUS, but the server doesn't grok it */
355 if (error
== -ENOTSUPP
&& desc
->plus
) {
356 NFS_SERVER(inode
)->caps
&= ~NFS_CAP_READDIRPLUS
;
357 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
363 desc
->timestamp
= timestamp
;
364 desc
->gencount
= gencount
;
369 static int xdr_decode(nfs_readdir_descriptor_t
*desc
,
370 struct nfs_entry
*entry
, struct xdr_stream
*xdr
)
374 error
= desc
->decode(xdr
, entry
, desc
->plus
);
377 entry
->fattr
->time_start
= desc
->timestamp
;
378 entry
->fattr
->gencount
= desc
->gencount
;
382 /* Match file and dirent using either filehandle or fileid
383 * Note: caller is responsible for checking the fsid
386 int nfs_same_file(struct dentry
*dentry
, struct nfs_entry
*entry
)
389 struct nfs_inode
*nfsi
;
391 if (d_really_is_negative(dentry
))
394 inode
= d_inode(dentry
);
395 if (is_bad_inode(inode
) || NFS_STALE(inode
))
399 if (entry
->fattr
->fileid
!= nfsi
->fileid
)
401 if (entry
->fh
->size
&& nfs_compare_fh(entry
->fh
, &nfsi
->fh
) != 0)
407 bool nfs_use_readdirplus(struct inode
*dir
, struct dir_context
*ctx
)
409 if (!nfs_server_capable(dir
, NFS_CAP_READDIRPLUS
))
411 if (test_and_clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(dir
)->flags
))
419 * This function is called by the lookup and getattr code to request the
420 * use of readdirplus to accelerate any future lookups in the same
423 void nfs_advise_use_readdirplus(struct inode
*dir
)
425 struct nfs_inode
*nfsi
= NFS_I(dir
);
427 if (nfs_server_capable(dir
, NFS_CAP_READDIRPLUS
) &&
428 !list_empty(&nfsi
->open_files
))
429 set_bit(NFS_INO_ADVISE_RDPLUS
, &nfsi
->flags
);
433 * This function is mainly for use by nfs_getattr().
435 * If this is an 'ls -l', we want to force use of readdirplus.
436 * Do this by checking if there is an active file descriptor
437 * and calling nfs_advise_use_readdirplus, then forcing a
440 void nfs_force_use_readdirplus(struct inode
*dir
)
442 struct nfs_inode
*nfsi
= NFS_I(dir
);
444 if (nfs_server_capable(dir
, NFS_CAP_READDIRPLUS
) &&
445 !list_empty(&nfsi
->open_files
)) {
446 set_bit(NFS_INO_ADVISE_RDPLUS
, &nfsi
->flags
);
447 invalidate_mapping_pages(dir
->i_mapping
, 0, -1);
452 void nfs_prime_dcache(struct dentry
*parent
, struct nfs_entry
*entry
)
454 struct qstr filename
= QSTR_INIT(entry
->name
, entry
->len
);
455 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq
);
456 struct dentry
*dentry
;
457 struct dentry
*alias
;
458 struct inode
*dir
= d_inode(parent
);
462 if (!(entry
->fattr
->valid
& NFS_ATTR_FATTR_FILEID
))
464 if (!(entry
->fattr
->valid
& NFS_ATTR_FATTR_FSID
))
466 if (filename
.len
== 0)
468 /* Validate that the name doesn't contain any illegal '\0' */
469 if (strnlen(filename
.name
, filename
.len
) != filename
.len
)
472 if (strnchr(filename
.name
, filename
.len
, '/'))
474 if (filename
.name
[0] == '.') {
475 if (filename
.len
== 1)
477 if (filename
.len
== 2 && filename
.name
[1] == '.')
480 filename
.hash
= full_name_hash(parent
, filename
.name
, filename
.len
);
482 dentry
= d_lookup(parent
, &filename
);
485 dentry
= d_alloc_parallel(parent
, &filename
, &wq
);
489 if (!d_in_lookup(dentry
)) {
490 /* Is there a mountpoint here? If so, just exit */
491 if (!nfs_fsid_equal(&NFS_SB(dentry
->d_sb
)->fsid
,
492 &entry
->fattr
->fsid
))
494 if (nfs_same_file(dentry
, entry
)) {
495 if (!entry
->fh
->size
)
497 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
498 status
= nfs_refresh_inode(d_inode(dentry
), entry
->fattr
);
500 nfs_setsecurity(d_inode(dentry
), entry
->fattr
, entry
->label
);
503 d_invalidate(dentry
);
509 if (!entry
->fh
->size
) {
510 d_lookup_done(dentry
);
514 inode
= nfs_fhget(dentry
->d_sb
, entry
->fh
, entry
->fattr
, entry
->label
);
515 alias
= d_splice_alias(inode
, dentry
);
516 d_lookup_done(dentry
);
523 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
528 /* Perform conversion from xdr to cache array */
530 int nfs_readdir_page_filler(nfs_readdir_descriptor_t
*desc
, struct nfs_entry
*entry
,
531 struct page
**xdr_pages
, struct page
*page
, unsigned int buflen
)
533 struct xdr_stream stream
;
535 struct page
*scratch
;
536 struct nfs_cache_array
*array
;
537 unsigned int count
= 0;
540 scratch
= alloc_page(GFP_KERNEL
);
547 xdr_init_decode_pages(&stream
, &buf
, xdr_pages
, buflen
);
548 xdr_set_scratch_buffer(&stream
, page_address(scratch
), PAGE_SIZE
);
551 status
= xdr_decode(desc
, entry
, &stream
);
553 if (status
== -EAGAIN
)
561 nfs_prime_dcache(file_dentry(desc
->file
), entry
);
563 status
= nfs_readdir_add_to_array(entry
, page
);
566 } while (!entry
->eof
);
569 if (count
== 0 || (status
== -EBADCOOKIE
&& entry
->eof
!= 0)) {
571 array
->eof_index
= array
->size
;
581 void nfs_readdir_free_pages(struct page
**pages
, unsigned int npages
)
584 for (i
= 0; i
< npages
; i
++)
589 * nfs_readdir_large_page will allocate pages that must be freed with a call
590 * to nfs_readdir_free_pagearray
593 int nfs_readdir_alloc_pages(struct page
**pages
, unsigned int npages
)
597 for (i
= 0; i
< npages
; i
++) {
598 struct page
*page
= alloc_page(GFP_KERNEL
);
606 nfs_readdir_free_pages(pages
, i
);
611 int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t
*desc
, struct page
*page
, struct inode
*inode
)
613 struct page
*pages
[NFS_MAX_READDIR_PAGES
];
614 struct nfs_entry entry
;
615 struct file
*file
= desc
->file
;
616 struct nfs_cache_array
*array
;
617 int status
= -ENOMEM
;
618 unsigned int array_size
= ARRAY_SIZE(pages
);
620 entry
.prev_cookie
= 0;
621 entry
.cookie
= desc
->last_cookie
;
623 entry
.fh
= nfs_alloc_fhandle();
624 entry
.fattr
= nfs_alloc_fattr();
625 entry
.server
= NFS_SERVER(inode
);
626 if (entry
.fh
== NULL
|| entry
.fattr
== NULL
)
629 entry
.label
= nfs4_label_alloc(NFS_SERVER(inode
), GFP_NOWAIT
);
630 if (IS_ERR(entry
.label
)) {
631 status
= PTR_ERR(entry
.label
);
636 memset(array
, 0, sizeof(struct nfs_cache_array
));
637 array
->eof_index
= -1;
639 status
= nfs_readdir_alloc_pages(pages
, array_size
);
641 goto out_release_array
;
644 status
= nfs_readdir_xdr_filler(pages
, desc
, &entry
, file
, inode
);
649 status
= nfs_readdir_page_filler(desc
, &entry
, pages
, page
, pglen
);
651 if (status
== -ENOSPC
)
655 } while (array
->eof_index
< 0);
657 nfs_readdir_free_pages(pages
, array_size
);
660 nfs4_label_free(entry
.label
);
662 nfs_free_fattr(entry
.fattr
);
663 nfs_free_fhandle(entry
.fh
);
668 * Now we cache directories properly, by converting xdr information
669 * to an array that can be used for lookups later. This results in
670 * fewer cache pages, since we can store more information on each page.
671 * We only need to convert from xdr once so future lookups are much simpler
674 int nfs_readdir_filler(nfs_readdir_descriptor_t
*desc
, struct page
* page
)
676 struct inode
*inode
= file_inode(desc
->file
);
679 ret
= nfs_readdir_xdr_to_array(desc
, page
, inode
);
682 SetPageUptodate(page
);
684 if (invalidate_inode_pages2_range(inode
->i_mapping
, page
->index
+ 1, -1) < 0) {
685 /* Should never happen */
686 nfs_zap_mapping(inode
, inode
->i_mapping
);
696 void cache_page_release(nfs_readdir_descriptor_t
*desc
)
698 if (!desc
->page
->mapping
)
699 nfs_readdir_clear_array(desc
->page
);
700 put_page(desc
->page
);
705 struct page
*get_cache_page(nfs_readdir_descriptor_t
*desc
)
707 return read_cache_page(desc
->file
->f_mapping
,
708 desc
->page_index
, (filler_t
*)nfs_readdir_filler
, desc
);
712 * Returns 0 if desc->dir_cookie was found on page desc->page_index
715 int find_cache_page(nfs_readdir_descriptor_t
*desc
)
719 desc
->page
= get_cache_page(desc
);
720 if (IS_ERR(desc
->page
))
721 return PTR_ERR(desc
->page
);
723 res
= nfs_readdir_search_array(desc
);
725 cache_page_release(desc
);
729 /* Search for desc->dir_cookie from the beginning of the page cache */
731 int readdir_search_pagecache(nfs_readdir_descriptor_t
*desc
)
735 if (desc
->page_index
== 0) {
736 desc
->current_index
= 0;
737 desc
->last_cookie
= 0;
740 res
= find_cache_page(desc
);
741 } while (res
== -EAGAIN
);
746 * Once we've found the start of the dirent within a page: fill 'er up...
749 int nfs_do_filldir(nfs_readdir_descriptor_t
*desc
)
751 struct file
*file
= desc
->file
;
754 struct nfs_cache_array
*array
= NULL
;
755 struct nfs_open_dir_context
*ctx
= file
->private_data
;
757 array
= kmap(desc
->page
);
758 for (i
= desc
->cache_entry_index
; i
< array
->size
; i
++) {
759 struct nfs_cache_array_entry
*ent
;
761 ent
= &array
->array
[i
];
762 if (!dir_emit(desc
->ctx
, ent
->string
.name
, ent
->string
.len
,
763 nfs_compat_user_ino64(ent
->ino
), ent
->d_type
)) {
768 if (i
< (array
->size
-1))
769 *desc
->dir_cookie
= array
->array
[i
+1].cookie
;
771 *desc
->dir_cookie
= array
->last_cookie
;
775 if (array
->eof_index
>= 0)
779 cache_page_release(desc
);
780 dfprintk(DIRCACHE
, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n",
781 (unsigned long long)*desc
->dir_cookie
, res
);
786 * If we cannot find a cookie in our cache, we suspect that this is
787 * because it points to a deleted file, so we ask the server to return
788 * whatever it thinks is the next entry. We then feed this to filldir.
789 * If all goes well, we should then be able to find our way round the
790 * cache on the next call to readdir_search_pagecache();
792 * NOTE: we cannot add the anonymous page to the pagecache because
793 * the data it contains might not be page aligned. Besides,
794 * we should already have a complete representation of the
795 * directory in the page cache by the time we get here.
798 int uncached_readdir(nfs_readdir_descriptor_t
*desc
)
800 struct page
*page
= NULL
;
802 struct inode
*inode
= file_inode(desc
->file
);
803 struct nfs_open_dir_context
*ctx
= desc
->file
->private_data
;
805 dfprintk(DIRCACHE
, "NFS: uncached_readdir() searching for cookie %Lu\n",
806 (unsigned long long)*desc
->dir_cookie
);
808 page
= alloc_page(GFP_HIGHUSER
);
814 desc
->page_index
= 0;
815 desc
->last_cookie
= *desc
->dir_cookie
;
819 status
= nfs_readdir_xdr_to_array(desc
, page
, inode
);
823 status
= nfs_do_filldir(desc
);
826 dfprintk(DIRCACHE
, "NFS: %s: returns %d\n",
830 cache_page_release(desc
);
834 /* The file offset position represents the dirent entry number. A
835 last cookie cache takes care of the common case of reading the
838 static int nfs_readdir(struct file
*file
, struct dir_context
*ctx
)
840 struct dentry
*dentry
= file_dentry(file
);
841 struct inode
*inode
= d_inode(dentry
);
842 nfs_readdir_descriptor_t my_desc
,
844 struct nfs_open_dir_context
*dir_ctx
= file
->private_data
;
847 dfprintk(FILE, "NFS: readdir(%pD2) starting at cookie %llu\n",
848 file
, (long long)ctx
->pos
);
849 nfs_inc_stats(inode
, NFSIOS_VFSGETDENTS
);
852 * ctx->pos points to the dirent entry number.
853 * *desc->dir_cookie has the cookie for the next entry. We have
854 * to either find the entry with the appropriate number or
855 * revalidate the cookie.
857 memset(desc
, 0, sizeof(*desc
));
861 desc
->dir_cookie
= &dir_ctx
->dir_cookie
;
862 desc
->decode
= NFS_PROTO(inode
)->decode_dirent
;
863 desc
->plus
= nfs_use_readdirplus(inode
, ctx
);
865 if (ctx
->pos
== 0 || nfs_attribute_cache_expired(inode
))
866 res
= nfs_revalidate_mapping(inode
, file
->f_mapping
);
871 res
= readdir_search_pagecache(desc
);
873 if (res
== -EBADCOOKIE
) {
875 /* This means either end of directory */
876 if (*desc
->dir_cookie
&& desc
->eof
== 0) {
877 /* Or that the server has 'lost' a cookie */
878 res
= uncached_readdir(desc
);
884 if (res
== -ETOOSMALL
&& desc
->plus
) {
885 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
886 nfs_zap_caches(inode
);
887 desc
->page_index
= 0;
895 res
= nfs_do_filldir(desc
);
898 } while (!desc
->eof
);
902 dfprintk(FILE, "NFS: readdir(%pD2) returns %d\n", file
, res
);
906 static loff_t
nfs_llseek_dir(struct file
*filp
, loff_t offset
, int whence
)
908 struct inode
*inode
= file_inode(filp
);
909 struct nfs_open_dir_context
*dir_ctx
= filp
->private_data
;
911 dfprintk(FILE, "NFS: llseek dir(%pD2, %lld, %d)\n",
912 filp
, offset
, whence
);
917 offset
+= filp
->f_pos
;
925 if (offset
!= filp
->f_pos
) {
926 filp
->f_pos
= offset
;
927 dir_ctx
->dir_cookie
= 0;
936 * All directory operations under NFS are synchronous, so fsync()
937 * is a dummy operation.
939 static int nfs_fsync_dir(struct file
*filp
, loff_t start
, loff_t end
,
942 struct inode
*inode
= file_inode(filp
);
944 dfprintk(FILE, "NFS: fsync dir(%pD2) datasync %d\n", filp
, datasync
);
947 nfs_inc_stats(inode
, NFSIOS_VFSFSYNC
);
953 * nfs_force_lookup_revalidate - Mark the directory as having changed
954 * @dir - pointer to directory inode
956 * This forces the revalidation code in nfs_lookup_revalidate() to do a
957 * full lookup on all child dentries of 'dir' whenever a change occurs
958 * on the server that might have invalidated our dcache.
960 * The caller should be holding dir->i_lock
962 void nfs_force_lookup_revalidate(struct inode
*dir
)
964 NFS_I(dir
)->cache_change_attribute
++;
966 EXPORT_SYMBOL_GPL(nfs_force_lookup_revalidate
);
969 * A check for whether or not the parent directory has changed.
970 * In the case it has, we assume that the dentries are untrustworthy
971 * and may need to be looked up again.
972 * If rcu_walk prevents us from performing a full check, return 0.
974 static int nfs_check_verifier(struct inode
*dir
, struct dentry
*dentry
,
979 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONE
)
981 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
983 /* Revalidate nfsi->cache_change_attribute before we declare a match */
984 if (nfs_mapping_need_revalidate_inode(dir
)) {
987 if (__nfs_revalidate_inode(NFS_SERVER(dir
), dir
) < 0)
990 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
996 * Use intent information to check whether or not we're going to do
997 * an O_EXCL create using this path component.
999 static int nfs_is_exclusive_create(struct inode
*dir
, unsigned int flags
)
1001 if (NFS_PROTO(dir
)->version
== 2)
1003 return flags
& LOOKUP_EXCL
;
1007 * Inode and filehandle revalidation for lookups.
1009 * We force revalidation in the cases where the VFS sets LOOKUP_REVAL,
1010 * or if the intent information indicates that we're about to open this
1011 * particular file and the "nocto" mount flag is not set.
1015 int nfs_lookup_verify_inode(struct inode
*inode
, unsigned int flags
)
1017 struct nfs_server
*server
= NFS_SERVER(inode
);
1020 if (IS_AUTOMOUNT(inode
))
1022 /* VFS wants an on-the-wire revalidation */
1023 if (flags
& LOOKUP_REVAL
)
1025 /* This is an open(2) */
1026 if ((flags
& LOOKUP_OPEN
) && !(server
->flags
& NFS_MOUNT_NOCTO
) &&
1027 (S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
)))
1030 return (inode
->i_nlink
== 0) ? -ENOENT
: 0;
1032 if (flags
& LOOKUP_RCU
)
1034 ret
= __nfs_revalidate_inode(server
, inode
);
1041 * We judge how long we want to trust negative
1042 * dentries by looking at the parent inode mtime.
1044 * If parent mtime has changed, we revalidate, else we wait for a
1045 * period corresponding to the parent's attribute cache timeout value.
1047 * If LOOKUP_RCU prevents us from performing a full check, return 1
1048 * suggesting a reval is needed.
1051 int nfs_neg_need_reval(struct inode
*dir
, struct dentry
*dentry
,
1054 /* Don't revalidate a negative dentry if we're creating a new file */
1055 if (flags
& LOOKUP_CREATE
)
1057 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONEG
)
1059 return !nfs_check_verifier(dir
, dentry
, flags
& LOOKUP_RCU
);
1063 * This is called every time the dcache has a lookup hit,
1064 * and we should check whether we can really trust that
1067 * NOTE! The hit can be a negative hit too, don't assume
1070 * If the parent directory is seen to have changed, we throw out the
1071 * cached dentry and do a new lookup.
1073 static int nfs_lookup_revalidate(struct dentry
*dentry
, unsigned int flags
)
1076 struct inode
*inode
;
1077 struct dentry
*parent
;
1078 struct nfs_fh
*fhandle
= NULL
;
1079 struct nfs_fattr
*fattr
= NULL
;
1080 struct nfs4_label
*label
= NULL
;
1083 if (flags
& LOOKUP_RCU
) {
1084 parent
= ACCESS_ONCE(dentry
->d_parent
);
1085 dir
= d_inode_rcu(parent
);
1089 parent
= dget_parent(dentry
);
1090 dir
= d_inode(parent
);
1092 nfs_inc_stats(dir
, NFSIOS_DENTRYREVALIDATE
);
1093 inode
= d_inode(dentry
);
1096 if (nfs_neg_need_reval(dir
, dentry
, flags
)) {
1097 if (flags
& LOOKUP_RCU
)
1104 if (is_bad_inode(inode
)) {
1105 if (flags
& LOOKUP_RCU
)
1107 dfprintk(LOOKUPCACHE
, "%s: %pd2 has dud inode\n",
1112 if (NFS_PROTO(dir
)->have_delegation(inode
, FMODE_READ
))
1113 goto out_set_verifier
;
1115 /* Force a full look up iff the parent directory has changed */
1116 if (!nfs_is_exclusive_create(dir
, flags
) &&
1117 nfs_check_verifier(dir
, dentry
, flags
& LOOKUP_RCU
)) {
1118 error
= nfs_lookup_verify_inode(inode
, flags
);
1120 if (flags
& LOOKUP_RCU
)
1122 if (error
== -ESTALE
)
1123 goto out_zap_parent
;
1126 nfs_advise_use_readdirplus(dir
);
1130 if (flags
& LOOKUP_RCU
)
1133 if (NFS_STALE(inode
))
1137 fhandle
= nfs_alloc_fhandle();
1138 fattr
= nfs_alloc_fattr();
1139 if (fhandle
== NULL
|| fattr
== NULL
)
1142 label
= nfs4_label_alloc(NFS_SERVER(inode
), GFP_NOWAIT
);
1146 trace_nfs_lookup_revalidate_enter(dir
, dentry
, flags
);
1147 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
, label
);
1148 trace_nfs_lookup_revalidate_exit(dir
, dentry
, flags
, error
);
1149 if (error
== -ESTALE
|| error
== -ENOENT
)
1153 if (nfs_compare_fh(NFS_FH(inode
), fhandle
))
1155 if ((error
= nfs_refresh_inode(inode
, fattr
)) != 0)
1158 nfs_setsecurity(inode
, fattr
, label
);
1160 nfs_free_fattr(fattr
);
1161 nfs_free_fhandle(fhandle
);
1162 nfs4_label_free(label
);
1164 /* set a readdirplus hint that we had a cache miss */
1165 nfs_force_use_readdirplus(dir
);
1168 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1170 if (flags
& LOOKUP_RCU
) {
1171 if (parent
!= ACCESS_ONCE(dentry
->d_parent
))
1175 dfprintk(LOOKUPCACHE
, "NFS: %s(%pd2) is valid\n",
1179 nfs_zap_caches(dir
);
1181 WARN_ON(flags
& LOOKUP_RCU
);
1182 nfs_free_fattr(fattr
);
1183 nfs_free_fhandle(fhandle
);
1184 nfs4_label_free(label
);
1185 nfs_mark_for_revalidate(dir
);
1186 if (inode
&& S_ISDIR(inode
->i_mode
)) {
1187 /* Purge readdir caches. */
1188 nfs_zap_caches(inode
);
1190 * We can't d_drop the root of a disconnected tree:
1191 * its d_hash is on the s_anon list and d_drop() would hide
1192 * it from shrink_dcache_for_unmount(), leading to busy
1193 * inodes on unmount and further oopses.
1195 if (IS_ROOT(dentry
))
1199 dfprintk(LOOKUPCACHE
, "NFS: %s(%pd2) is invalid\n",
1203 WARN_ON(flags
& LOOKUP_RCU
);
1204 nfs_free_fattr(fattr
);
1205 nfs_free_fhandle(fhandle
);
1206 nfs4_label_free(label
);
1208 dfprintk(LOOKUPCACHE
, "NFS: %s(%pd2) lookup returned error %d\n",
1209 __func__
, dentry
, error
);
1214 * A weaker form of d_revalidate for revalidating just the d_inode(dentry)
1215 * when we don't really care about the dentry name. This is called when a
1216 * pathwalk ends on a dentry that was not found via a normal lookup in the
1217 * parent dir (e.g.: ".", "..", procfs symlinks or mountpoint traversals).
1219 * In this situation, we just want to verify that the inode itself is OK
1220 * since the dentry might have changed on the server.
1222 static int nfs_weak_revalidate(struct dentry
*dentry
, unsigned int flags
)
1224 struct inode
*inode
= d_inode(dentry
);
1228 * I believe we can only get a negative dentry here in the case of a
1229 * procfs-style symlink. Just assume it's correct for now, but we may
1230 * eventually need to do something more here.
1233 dfprintk(LOOKUPCACHE
, "%s: %pd2 has negative inode\n",
1238 if (is_bad_inode(inode
)) {
1239 dfprintk(LOOKUPCACHE
, "%s: %pd2 has dud inode\n",
1244 if (nfs_mapping_need_revalidate_inode(inode
))
1245 error
= __nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
1246 dfprintk(LOOKUPCACHE
, "NFS: %s: inode %lu is %s\n",
1247 __func__
, inode
->i_ino
, error
? "invalid" : "valid");
1252 * This is called from dput() when d_count is going to 0.
1254 static int nfs_dentry_delete(const struct dentry
*dentry
)
1256 dfprintk(VFS
, "NFS: dentry_delete(%pd2, %x)\n",
1257 dentry
, dentry
->d_flags
);
1259 /* Unhash any dentry with a stale inode */
1260 if (d_really_is_positive(dentry
) && NFS_STALE(d_inode(dentry
)))
1263 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1264 /* Unhash it, so that ->d_iput() would be called */
1267 if (!(dentry
->d_sb
->s_flags
& MS_ACTIVE
)) {
1268 /* Unhash it, so that ancestors of killed async unlink
1269 * files will be cleaned up during umount */
1276 /* Ensure that we revalidate inode->i_nlink */
1277 static void nfs_drop_nlink(struct inode
*inode
)
1279 spin_lock(&inode
->i_lock
);
1280 /* drop the inode if we're reasonably sure this is the last link */
1281 if (inode
->i_nlink
== 1)
1283 NFS_I(inode
)->cache_validity
|= NFS_INO_INVALID_ATTR
;
1284 spin_unlock(&inode
->i_lock
);
1288 * Called when the dentry loses inode.
1289 * We use it to clean up silly-renamed files.
1291 static void nfs_dentry_iput(struct dentry
*dentry
, struct inode
*inode
)
1293 if (S_ISDIR(inode
->i_mode
))
1294 /* drop any readdir cache as it could easily be old */
1295 NFS_I(inode
)->cache_validity
|= NFS_INO_INVALID_DATA
;
1297 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1298 nfs_complete_unlink(dentry
, inode
);
1299 nfs_drop_nlink(inode
);
1304 static void nfs_d_release(struct dentry
*dentry
)
1306 /* free cached devname value, if it survived that far */
1307 if (unlikely(dentry
->d_fsdata
)) {
1308 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
)
1311 kfree(dentry
->d_fsdata
);
1315 const struct dentry_operations nfs_dentry_operations
= {
1316 .d_revalidate
= nfs_lookup_revalidate
,
1317 .d_weak_revalidate
= nfs_weak_revalidate
,
1318 .d_delete
= nfs_dentry_delete
,
1319 .d_iput
= nfs_dentry_iput
,
1320 .d_automount
= nfs_d_automount
,
1321 .d_release
= nfs_d_release
,
1323 EXPORT_SYMBOL_GPL(nfs_dentry_operations
);
1325 struct dentry
*nfs_lookup(struct inode
*dir
, struct dentry
* dentry
, unsigned int flags
)
1328 struct inode
*inode
= NULL
;
1329 struct nfs_fh
*fhandle
= NULL
;
1330 struct nfs_fattr
*fattr
= NULL
;
1331 struct nfs4_label
*label
= NULL
;
1334 dfprintk(VFS
, "NFS: lookup(%pd2)\n", dentry
);
1335 nfs_inc_stats(dir
, NFSIOS_VFSLOOKUP
);
1337 if (unlikely(dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
))
1338 return ERR_PTR(-ENAMETOOLONG
);
1341 * If we're doing an exclusive create, optimize away the lookup
1342 * but don't hash the dentry.
1344 if (nfs_is_exclusive_create(dir
, flags
))
1347 res
= ERR_PTR(-ENOMEM
);
1348 fhandle
= nfs_alloc_fhandle();
1349 fattr
= nfs_alloc_fattr();
1350 if (fhandle
== NULL
|| fattr
== NULL
)
1353 label
= nfs4_label_alloc(NFS_SERVER(dir
), GFP_NOWAIT
);
1357 trace_nfs_lookup_enter(dir
, dentry
, flags
);
1358 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
, label
);
1359 if (error
== -ENOENT
)
1362 res
= ERR_PTR(error
);
1365 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
, label
);
1366 res
= ERR_CAST(inode
);
1370 /* Notify readdir to use READDIRPLUS */
1371 nfs_force_use_readdirplus(dir
);
1374 res
= d_splice_alias(inode
, dentry
);
1380 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1382 trace_nfs_lookup_exit(dir
, dentry
, flags
, error
);
1383 nfs4_label_free(label
);
1385 nfs_free_fattr(fattr
);
1386 nfs_free_fhandle(fhandle
);
1389 EXPORT_SYMBOL_GPL(nfs_lookup
);
1391 #if IS_ENABLED(CONFIG_NFS_V4)
1392 static int nfs4_lookup_revalidate(struct dentry
*, unsigned int);
1394 const struct dentry_operations nfs4_dentry_operations
= {
1395 .d_revalidate
= nfs4_lookup_revalidate
,
1396 .d_delete
= nfs_dentry_delete
,
1397 .d_iput
= nfs_dentry_iput
,
1398 .d_automount
= nfs_d_automount
,
1399 .d_release
= nfs_d_release
,
1401 EXPORT_SYMBOL_GPL(nfs4_dentry_operations
);
1403 static fmode_t
flags_to_mode(int flags
)
1405 fmode_t res
= (__force fmode_t
)flags
& FMODE_EXEC
;
1406 if ((flags
& O_ACCMODE
) != O_WRONLY
)
1408 if ((flags
& O_ACCMODE
) != O_RDONLY
)
1413 static struct nfs_open_context
*create_nfs_open_context(struct dentry
*dentry
, int open_flags
, struct file
*filp
)
1415 return alloc_nfs_open_context(dentry
, flags_to_mode(open_flags
), filp
);
1418 static int do_open(struct inode
*inode
, struct file
*filp
)
1420 nfs_fscache_open_file(inode
, filp
);
1424 static int nfs_finish_open(struct nfs_open_context
*ctx
,
1425 struct dentry
*dentry
,
1426 struct file
*file
, unsigned open_flags
,
1431 err
= finish_open(file
, dentry
, do_open
, opened
);
1434 if (S_ISREG(file
->f_path
.dentry
->d_inode
->i_mode
))
1435 nfs_file_set_open_context(file
, ctx
);
1442 int nfs_atomic_open(struct inode
*dir
, struct dentry
*dentry
,
1443 struct file
*file
, unsigned open_flags
,
1444 umode_t mode
, int *opened
)
1446 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq
);
1447 struct nfs_open_context
*ctx
;
1449 struct iattr attr
= { .ia_valid
= ATTR_OPEN
};
1450 struct inode
*inode
;
1451 unsigned int lookup_flags
= 0;
1452 bool switched
= false;
1455 /* Expect a negative dentry */
1456 BUG_ON(d_inode(dentry
));
1458 dfprintk(VFS
, "NFS: atomic_open(%s/%lu), %pd\n",
1459 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1461 err
= nfs_check_flags(open_flags
);
1465 /* NFS only supports OPEN on regular files */
1466 if ((open_flags
& O_DIRECTORY
)) {
1467 if (!d_in_lookup(dentry
)) {
1469 * Hashed negative dentry with O_DIRECTORY: dentry was
1470 * revalidated and is fine, no need to perform lookup
1475 lookup_flags
= LOOKUP_OPEN
|LOOKUP_DIRECTORY
;
1479 if (dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
)
1480 return -ENAMETOOLONG
;
1482 if (open_flags
& O_CREAT
) {
1483 struct nfs_server
*server
= NFS_SERVER(dir
);
1485 if (!(server
->attr_bitmask
[2] & FATTR4_WORD2_MODE_UMASK
))
1486 mode
&= ~current_umask();
1488 attr
.ia_valid
|= ATTR_MODE
;
1489 attr
.ia_mode
= mode
;
1491 if (open_flags
& O_TRUNC
) {
1492 attr
.ia_valid
|= ATTR_SIZE
;
1496 if (!(open_flags
& O_CREAT
) && !d_in_lookup(dentry
)) {
1499 dentry
= d_alloc_parallel(dentry
->d_parent
,
1500 &dentry
->d_name
, &wq
);
1502 return PTR_ERR(dentry
);
1503 if (unlikely(!d_in_lookup(dentry
)))
1504 return finish_no_open(file
, dentry
);
1507 ctx
= create_nfs_open_context(dentry
, open_flags
, file
);
1512 trace_nfs_atomic_open_enter(dir
, ctx
, open_flags
);
1513 inode
= NFS_PROTO(dir
)->open_context(dir
, ctx
, open_flags
, &attr
, opened
);
1514 if (IS_ERR(inode
)) {
1515 err
= PTR_ERR(inode
);
1516 trace_nfs_atomic_open_exit(dir
, ctx
, open_flags
, err
);
1517 put_nfs_open_context(ctx
);
1521 d_splice_alias(NULL
, dentry
);
1522 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1528 if (!(open_flags
& O_NOFOLLOW
))
1538 err
= nfs_finish_open(ctx
, ctx
->dentry
, file
, open_flags
, opened
);
1539 trace_nfs_atomic_open_exit(dir
, ctx
, open_flags
, err
);
1540 put_nfs_open_context(ctx
);
1542 if (unlikely(switched
)) {
1543 d_lookup_done(dentry
);
1549 res
= nfs_lookup(dir
, dentry
, lookup_flags
);
1551 d_lookup_done(dentry
);
1558 return PTR_ERR(res
);
1559 return finish_no_open(file
, res
);
1561 EXPORT_SYMBOL_GPL(nfs_atomic_open
);
1563 static int nfs4_lookup_revalidate(struct dentry
*dentry
, unsigned int flags
)
1565 struct inode
*inode
;
1568 if (!(flags
& LOOKUP_OPEN
) || (flags
& LOOKUP_DIRECTORY
))
1570 if (d_mountpoint(dentry
))
1572 if (NFS_SB(dentry
->d_sb
)->caps
& NFS_CAP_ATOMIC_OPEN_V1
)
1575 inode
= d_inode(dentry
);
1577 /* We can't create new files in nfs_open_revalidate(), so we
1578 * optimize away revalidation of negative dentries.
1580 if (inode
== NULL
) {
1581 struct dentry
*parent
;
1584 if (flags
& LOOKUP_RCU
) {
1585 parent
= ACCESS_ONCE(dentry
->d_parent
);
1586 dir
= d_inode_rcu(parent
);
1590 parent
= dget_parent(dentry
);
1591 dir
= d_inode(parent
);
1593 if (!nfs_neg_need_reval(dir
, dentry
, flags
))
1595 else if (flags
& LOOKUP_RCU
)
1597 if (!(flags
& LOOKUP_RCU
))
1599 else if (parent
!= ACCESS_ONCE(dentry
->d_parent
))
1604 /* NFS only supports OPEN on regular files */
1605 if (!S_ISREG(inode
->i_mode
))
1607 /* We cannot do exclusive creation on a positive dentry */
1608 if (flags
& LOOKUP_EXCL
)
1611 /* Let f_op->open() actually open (and revalidate) the file */
1618 return nfs_lookup_revalidate(dentry
, flags
);
1621 #endif /* CONFIG_NFSV4 */
1624 * Code common to create, mkdir, and mknod.
1626 int nfs_instantiate(struct dentry
*dentry
, struct nfs_fh
*fhandle
,
1627 struct nfs_fattr
*fattr
,
1628 struct nfs4_label
*label
)
1630 struct dentry
*parent
= dget_parent(dentry
);
1631 struct inode
*dir
= d_inode(parent
);
1632 struct inode
*inode
;
1633 int error
= -EACCES
;
1637 /* We may have been initialized further down */
1638 if (d_really_is_positive(dentry
))
1640 if (fhandle
->size
== 0) {
1641 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
, NULL
);
1645 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1646 if (!(fattr
->valid
& NFS_ATTR_FATTR
)) {
1647 struct nfs_server
*server
= NFS_SB(dentry
->d_sb
);
1648 error
= server
->nfs_client
->rpc_ops
->getattr(server
, fhandle
, fattr
, NULL
);
1652 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
, label
);
1653 error
= PTR_ERR(inode
);
1656 d_add(dentry
, inode
);
1661 nfs_mark_for_revalidate(dir
);
1665 EXPORT_SYMBOL_GPL(nfs_instantiate
);
1668 * Following a failed create operation, we drop the dentry rather
1669 * than retain a negative dentry. This avoids a problem in the event
1670 * that the operation succeeded on the server, but an error in the
1671 * reply path made it appear to have failed.
1673 int nfs_create(struct inode
*dir
, struct dentry
*dentry
,
1674 umode_t mode
, bool excl
)
1677 int open_flags
= excl
? O_CREAT
| O_EXCL
: O_CREAT
;
1680 dfprintk(VFS
, "NFS: create(%s/%lu), %pd\n",
1681 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1683 attr
.ia_mode
= mode
;
1684 attr
.ia_valid
= ATTR_MODE
;
1686 trace_nfs_create_enter(dir
, dentry
, open_flags
);
1687 error
= NFS_PROTO(dir
)->create(dir
, dentry
, &attr
, open_flags
);
1688 trace_nfs_create_exit(dir
, dentry
, open_flags
, error
);
1696 EXPORT_SYMBOL_GPL(nfs_create
);
1699 * See comments for nfs_proc_create regarding failed operations.
1702 nfs_mknod(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
, dev_t rdev
)
1707 dfprintk(VFS
, "NFS: mknod(%s/%lu), %pd\n",
1708 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1710 attr
.ia_mode
= mode
;
1711 attr
.ia_valid
= ATTR_MODE
;
1713 trace_nfs_mknod_enter(dir
, dentry
);
1714 status
= NFS_PROTO(dir
)->mknod(dir
, dentry
, &attr
, rdev
);
1715 trace_nfs_mknod_exit(dir
, dentry
, status
);
1723 EXPORT_SYMBOL_GPL(nfs_mknod
);
1726 * See comments for nfs_proc_create regarding failed operations.
1728 int nfs_mkdir(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
)
1733 dfprintk(VFS
, "NFS: mkdir(%s/%lu), %pd\n",
1734 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1736 attr
.ia_valid
= ATTR_MODE
;
1737 attr
.ia_mode
= mode
| S_IFDIR
;
1739 trace_nfs_mkdir_enter(dir
, dentry
);
1740 error
= NFS_PROTO(dir
)->mkdir(dir
, dentry
, &attr
);
1741 trace_nfs_mkdir_exit(dir
, dentry
, error
);
1749 EXPORT_SYMBOL_GPL(nfs_mkdir
);
1751 static void nfs_dentry_handle_enoent(struct dentry
*dentry
)
1753 if (simple_positive(dentry
))
1757 int nfs_rmdir(struct inode
*dir
, struct dentry
*dentry
)
1761 dfprintk(VFS
, "NFS: rmdir(%s/%lu), %pd\n",
1762 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1764 trace_nfs_rmdir_enter(dir
, dentry
);
1765 if (d_really_is_positive(dentry
)) {
1766 down_write(&NFS_I(d_inode(dentry
))->rmdir_sem
);
1767 error
= NFS_PROTO(dir
)->rmdir(dir
, &dentry
->d_name
);
1768 /* Ensure the VFS deletes this inode */
1771 clear_nlink(d_inode(dentry
));
1774 nfs_dentry_handle_enoent(dentry
);
1776 up_write(&NFS_I(d_inode(dentry
))->rmdir_sem
);
1778 error
= NFS_PROTO(dir
)->rmdir(dir
, &dentry
->d_name
);
1779 trace_nfs_rmdir_exit(dir
, dentry
, error
);
1783 EXPORT_SYMBOL_GPL(nfs_rmdir
);
1786 * Remove a file after making sure there are no pending writes,
1787 * and after checking that the file has only one user.
1789 * We invalidate the attribute cache and free the inode prior to the operation
1790 * to avoid possible races if the server reuses the inode.
1792 static int nfs_safe_remove(struct dentry
*dentry
)
1794 struct inode
*dir
= d_inode(dentry
->d_parent
);
1795 struct inode
*inode
= d_inode(dentry
);
1798 dfprintk(VFS
, "NFS: safe_remove(%pd2)\n", dentry
);
1800 /* If the dentry was sillyrenamed, we simply call d_delete() */
1801 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1806 trace_nfs_remove_enter(dir
, dentry
);
1807 if (inode
!= NULL
) {
1808 NFS_PROTO(inode
)->return_delegation(inode
);
1809 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1811 nfs_drop_nlink(inode
);
1813 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1814 if (error
== -ENOENT
)
1815 nfs_dentry_handle_enoent(dentry
);
1816 trace_nfs_remove_exit(dir
, dentry
, error
);
1821 /* We do silly rename. In case sillyrename() returns -EBUSY, the inode
1822 * belongs to an active ".nfs..." file and we return -EBUSY.
1824 * If sillyrename() returns 0, we do nothing, otherwise we unlink.
1826 int nfs_unlink(struct inode
*dir
, struct dentry
*dentry
)
1829 int need_rehash
= 0;
1831 dfprintk(VFS
, "NFS: unlink(%s/%lu, %pd)\n", dir
->i_sb
->s_id
,
1832 dir
->i_ino
, dentry
);
1834 trace_nfs_unlink_enter(dir
, dentry
);
1835 spin_lock(&dentry
->d_lock
);
1836 if (d_count(dentry
) > 1) {
1837 spin_unlock(&dentry
->d_lock
);
1838 /* Start asynchronous writeout of the inode */
1839 write_inode_now(d_inode(dentry
), 0);
1840 error
= nfs_sillyrename(dir
, dentry
);
1843 if (!d_unhashed(dentry
)) {
1847 spin_unlock(&dentry
->d_lock
);
1848 error
= nfs_safe_remove(dentry
);
1849 if (!error
|| error
== -ENOENT
) {
1850 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1851 } else if (need_rehash
)
1854 trace_nfs_unlink_exit(dir
, dentry
, error
);
1857 EXPORT_SYMBOL_GPL(nfs_unlink
);
1860 * To create a symbolic link, most file systems instantiate a new inode,
1861 * add a page to it containing the path, then write it out to the disk
1862 * using prepare_write/commit_write.
1864 * Unfortunately the NFS client can't create the in-core inode first
1865 * because it needs a file handle to create an in-core inode (see
1866 * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the
1867 * symlink request has completed on the server.
1869 * So instead we allocate a raw page, copy the symname into it, then do
1870 * the SYMLINK request with the page as the buffer. If it succeeds, we
1871 * now have a new file handle and can instantiate an in-core NFS inode
1872 * and move the raw page into its mapping.
1874 int nfs_symlink(struct inode
*dir
, struct dentry
*dentry
, const char *symname
)
1879 unsigned int pathlen
= strlen(symname
);
1882 dfprintk(VFS
, "NFS: symlink(%s/%lu, %pd, %s)\n", dir
->i_sb
->s_id
,
1883 dir
->i_ino
, dentry
, symname
);
1885 if (pathlen
> PAGE_SIZE
)
1886 return -ENAMETOOLONG
;
1888 attr
.ia_mode
= S_IFLNK
| S_IRWXUGO
;
1889 attr
.ia_valid
= ATTR_MODE
;
1891 page
= alloc_page(GFP_USER
);
1895 kaddr
= page_address(page
);
1896 memcpy(kaddr
, symname
, pathlen
);
1897 if (pathlen
< PAGE_SIZE
)
1898 memset(kaddr
+ pathlen
, 0, PAGE_SIZE
- pathlen
);
1900 trace_nfs_symlink_enter(dir
, dentry
);
1901 error
= NFS_PROTO(dir
)->symlink(dir
, dentry
, page
, pathlen
, &attr
);
1902 trace_nfs_symlink_exit(dir
, dentry
, error
);
1904 dfprintk(VFS
, "NFS: symlink(%s/%lu, %pd, %s) error %d\n",
1905 dir
->i_sb
->s_id
, dir
->i_ino
,
1906 dentry
, symname
, error
);
1913 * No big deal if we can't add this page to the page cache here.
1914 * READLINK will get the missing page from the server if needed.
1916 if (!add_to_page_cache_lru(page
, d_inode(dentry
)->i_mapping
, 0,
1918 SetPageUptodate(page
);
1921 * add_to_page_cache_lru() grabs an extra page refcount.
1922 * Drop it here to avoid leaking this page later.
1930 EXPORT_SYMBOL_GPL(nfs_symlink
);
1933 nfs_link(struct dentry
*old_dentry
, struct inode
*dir
, struct dentry
*dentry
)
1935 struct inode
*inode
= d_inode(old_dentry
);
1938 dfprintk(VFS
, "NFS: link(%pd2 -> %pd2)\n",
1939 old_dentry
, dentry
);
1941 trace_nfs_link_enter(inode
, dir
, dentry
);
1942 NFS_PROTO(inode
)->return_delegation(inode
);
1945 error
= NFS_PROTO(dir
)->link(inode
, dir
, &dentry
->d_name
);
1948 d_add(dentry
, inode
);
1950 trace_nfs_link_exit(inode
, dir
, dentry
, error
);
1953 EXPORT_SYMBOL_GPL(nfs_link
);
1957 * FIXME: Some nfsds, like the Linux user space nfsd, may generate a
1958 * different file handle for the same inode after a rename (e.g. when
1959 * moving to a different directory). A fail-safe method to do so would
1960 * be to look up old_dir/old_name, create a link to new_dir/new_name and
1961 * rename the old file using the sillyrename stuff. This way, the original
1962 * file in old_dir will go away when the last process iput()s the inode.
1966 * It actually works quite well. One needs to have the possibility for
1967 * at least one ".nfs..." file in each directory the file ever gets
1968 * moved or linked to which happens automagically with the new
1969 * implementation that only depends on the dcache stuff instead of
1970 * using the inode layer
1972 * Unfortunately, things are a little more complicated than indicated
1973 * above. For a cross-directory move, we want to make sure we can get
1974 * rid of the old inode after the operation. This means there must be
1975 * no pending writes (if it's a file), and the use count must be 1.
1976 * If these conditions are met, we can drop the dentries before doing
1979 int nfs_rename(struct inode
*old_dir
, struct dentry
*old_dentry
,
1980 struct inode
*new_dir
, struct dentry
*new_dentry
,
1983 struct inode
*old_inode
= d_inode(old_dentry
);
1984 struct inode
*new_inode
= d_inode(new_dentry
);
1985 struct dentry
*dentry
= NULL
, *rehash
= NULL
;
1986 struct rpc_task
*task
;
1992 dfprintk(VFS
, "NFS: rename(%pd2 -> %pd2, ct=%d)\n",
1993 old_dentry
, new_dentry
,
1994 d_count(new_dentry
));
1996 trace_nfs_rename_enter(old_dir
, old_dentry
, new_dir
, new_dentry
);
1998 * For non-directories, check whether the target is busy and if so,
1999 * make a copy of the dentry and then do a silly-rename. If the
2000 * silly-rename succeeds, the copied dentry is hashed and becomes
2003 if (new_inode
&& !S_ISDIR(new_inode
->i_mode
)) {
2005 * To prevent any new references to the target during the
2006 * rename, we unhash the dentry in advance.
2008 if (!d_unhashed(new_dentry
)) {
2010 rehash
= new_dentry
;
2013 if (d_count(new_dentry
) > 2) {
2016 /* copy the target dentry's name */
2017 dentry
= d_alloc(new_dentry
->d_parent
,
2018 &new_dentry
->d_name
);
2022 /* silly-rename the existing target ... */
2023 err
= nfs_sillyrename(new_dir
, new_dentry
);
2027 new_dentry
= dentry
;
2033 NFS_PROTO(old_inode
)->return_delegation(old_inode
);
2034 if (new_inode
!= NULL
)
2035 NFS_PROTO(new_inode
)->return_delegation(new_inode
);
2037 task
= nfs_async_rename(old_dir
, new_dir
, old_dentry
, new_dentry
, NULL
);
2039 error
= PTR_ERR(task
);
2043 error
= rpc_wait_for_completion_task(task
);
2045 ((struct nfs_renamedata
*)task
->tk_calldata
)->cancelled
= 1;
2046 /* Paired with the atomic_dec_and_test() barrier in rpc_do_put_task() */
2049 error
= task
->tk_status
;
2051 nfs_mark_for_revalidate(old_inode
);
2055 trace_nfs_rename_exit(old_dir
, old_dentry
,
2056 new_dir
, new_dentry
, error
);
2058 if (new_inode
!= NULL
)
2059 nfs_drop_nlink(new_inode
);
2061 * The d_move() should be here instead of in an async RPC completion
2062 * handler because we need the proper locks to move the dentry. If
2063 * we're interrupted by a signal, the async RPC completion handler
2064 * should mark the directories for revalidation.
2066 d_move(old_dentry
, new_dentry
);
2067 nfs_set_verifier(new_dentry
,
2068 nfs_save_change_attribute(new_dir
));
2069 } else if (error
== -ENOENT
)
2070 nfs_dentry_handle_enoent(old_dentry
);
2072 /* new dentry created? */
2077 EXPORT_SYMBOL_GPL(nfs_rename
);
2079 static DEFINE_SPINLOCK(nfs_access_lru_lock
);
2080 static LIST_HEAD(nfs_access_lru_list
);
2081 static atomic_long_t nfs_access_nr_entries
;
2083 static unsigned long nfs_access_max_cachesize
= ULONG_MAX
;
2084 module_param(nfs_access_max_cachesize
, ulong
, 0644);
2085 MODULE_PARM_DESC(nfs_access_max_cachesize
, "NFS access maximum total cache length");
2087 static void nfs_access_free_entry(struct nfs_access_entry
*entry
)
2089 put_rpccred(entry
->cred
);
2090 kfree_rcu(entry
, rcu_head
);
2091 smp_mb__before_atomic();
2092 atomic_long_dec(&nfs_access_nr_entries
);
2093 smp_mb__after_atomic();
2096 static void nfs_access_free_list(struct list_head
*head
)
2098 struct nfs_access_entry
*cache
;
2100 while (!list_empty(head
)) {
2101 cache
= list_entry(head
->next
, struct nfs_access_entry
, lru
);
2102 list_del(&cache
->lru
);
2103 nfs_access_free_entry(cache
);
2107 static unsigned long
2108 nfs_do_access_cache_scan(unsigned int nr_to_scan
)
2111 struct nfs_inode
*nfsi
, *next
;
2112 struct nfs_access_entry
*cache
;
2115 spin_lock(&nfs_access_lru_lock
);
2116 list_for_each_entry_safe(nfsi
, next
, &nfs_access_lru_list
, access_cache_inode_lru
) {
2117 struct inode
*inode
;
2119 if (nr_to_scan
-- == 0)
2121 inode
= &nfsi
->vfs_inode
;
2122 spin_lock(&inode
->i_lock
);
2123 if (list_empty(&nfsi
->access_cache_entry_lru
))
2124 goto remove_lru_entry
;
2125 cache
= list_entry(nfsi
->access_cache_entry_lru
.next
,
2126 struct nfs_access_entry
, lru
);
2127 list_move(&cache
->lru
, &head
);
2128 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
2130 if (!list_empty(&nfsi
->access_cache_entry_lru
))
2131 list_move_tail(&nfsi
->access_cache_inode_lru
,
2132 &nfs_access_lru_list
);
2135 list_del_init(&nfsi
->access_cache_inode_lru
);
2136 smp_mb__before_atomic();
2137 clear_bit(NFS_INO_ACL_LRU_SET
, &nfsi
->flags
);
2138 smp_mb__after_atomic();
2140 spin_unlock(&inode
->i_lock
);
2142 spin_unlock(&nfs_access_lru_lock
);
2143 nfs_access_free_list(&head
);
2148 nfs_access_cache_scan(struct shrinker
*shrink
, struct shrink_control
*sc
)
2150 int nr_to_scan
= sc
->nr_to_scan
;
2151 gfp_t gfp_mask
= sc
->gfp_mask
;
2153 if ((gfp_mask
& GFP_KERNEL
) != GFP_KERNEL
)
2155 return nfs_do_access_cache_scan(nr_to_scan
);
2160 nfs_access_cache_count(struct shrinker
*shrink
, struct shrink_control
*sc
)
2162 return vfs_pressure_ratio(atomic_long_read(&nfs_access_nr_entries
));
2166 nfs_access_cache_enforce_limit(void)
2168 long nr_entries
= atomic_long_read(&nfs_access_nr_entries
);
2170 unsigned int nr_to_scan
;
2172 if (nr_entries
< 0 || nr_entries
<= nfs_access_max_cachesize
)
2175 diff
= nr_entries
- nfs_access_max_cachesize
;
2176 if (diff
< nr_to_scan
)
2178 nfs_do_access_cache_scan(nr_to_scan
);
2181 static void __nfs_access_zap_cache(struct nfs_inode
*nfsi
, struct list_head
*head
)
2183 struct rb_root
*root_node
= &nfsi
->access_cache
;
2185 struct nfs_access_entry
*entry
;
2187 /* Unhook entries from the cache */
2188 while ((n
= rb_first(root_node
)) != NULL
) {
2189 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
2190 rb_erase(n
, root_node
);
2191 list_move(&entry
->lru
, head
);
2193 nfsi
->cache_validity
&= ~NFS_INO_INVALID_ACCESS
;
2196 void nfs_access_zap_cache(struct inode
*inode
)
2200 if (test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
) == 0)
2202 /* Remove from global LRU init */
2203 spin_lock(&nfs_access_lru_lock
);
2204 if (test_and_clear_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
2205 list_del_init(&NFS_I(inode
)->access_cache_inode_lru
);
2207 spin_lock(&inode
->i_lock
);
2208 __nfs_access_zap_cache(NFS_I(inode
), &head
);
2209 spin_unlock(&inode
->i_lock
);
2210 spin_unlock(&nfs_access_lru_lock
);
2211 nfs_access_free_list(&head
);
2213 EXPORT_SYMBOL_GPL(nfs_access_zap_cache
);
2215 static struct nfs_access_entry
*nfs_access_search_rbtree(struct inode
*inode
, struct rpc_cred
*cred
)
2217 struct rb_node
*n
= NFS_I(inode
)->access_cache
.rb_node
;
2218 struct nfs_access_entry
*entry
;
2221 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
2223 if (cred
< entry
->cred
)
2225 else if (cred
> entry
->cred
)
2233 static int nfs_access_get_cached(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_access_entry
*res
, bool may_block
)
2235 struct nfs_inode
*nfsi
= NFS_I(inode
);
2236 struct nfs_access_entry
*cache
;
2240 spin_lock(&inode
->i_lock
);
2242 if (nfsi
->cache_validity
& NFS_INO_INVALID_ACCESS
)
2244 cache
= nfs_access_search_rbtree(inode
, cred
);
2248 /* Found an entry, is our attribute cache valid? */
2249 if (!nfs_check_cache_invalid(inode
, NFS_INO_INVALID_ACCESS
))
2256 spin_unlock(&inode
->i_lock
);
2257 err
= __nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
2260 spin_lock(&inode
->i_lock
);
2263 res
->cred
= cache
->cred
;
2264 res
->mask
= cache
->mask
;
2265 list_move_tail(&cache
->lru
, &nfsi
->access_cache_entry_lru
);
2268 spin_unlock(&inode
->i_lock
);
2271 spin_unlock(&inode
->i_lock
);
2272 nfs_access_zap_cache(inode
);
2276 static int nfs_access_get_cached_rcu(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_access_entry
*res
)
2278 /* Only check the most recently returned cache entry,
2279 * but do it without locking.
2281 struct nfs_inode
*nfsi
= NFS_I(inode
);
2282 struct nfs_access_entry
*cache
;
2284 struct list_head
*lh
;
2287 if (nfsi
->cache_validity
& NFS_INO_INVALID_ACCESS
)
2289 lh
= rcu_dereference(nfsi
->access_cache_entry_lru
.prev
);
2290 cache
= list_entry(lh
, struct nfs_access_entry
, lru
);
2291 if (lh
== &nfsi
->access_cache_entry_lru
||
2292 cred
!= cache
->cred
)
2296 if (nfs_check_cache_invalid(inode
, NFS_INO_INVALID_ACCESS
))
2298 res
->cred
= cache
->cred
;
2299 res
->mask
= cache
->mask
;
2306 static void nfs_access_add_rbtree(struct inode
*inode
, struct nfs_access_entry
*set
)
2308 struct nfs_inode
*nfsi
= NFS_I(inode
);
2309 struct rb_root
*root_node
= &nfsi
->access_cache
;
2310 struct rb_node
**p
= &root_node
->rb_node
;
2311 struct rb_node
*parent
= NULL
;
2312 struct nfs_access_entry
*entry
;
2314 spin_lock(&inode
->i_lock
);
2315 while (*p
!= NULL
) {
2317 entry
= rb_entry(parent
, struct nfs_access_entry
, rb_node
);
2319 if (set
->cred
< entry
->cred
)
2320 p
= &parent
->rb_left
;
2321 else if (set
->cred
> entry
->cred
)
2322 p
= &parent
->rb_right
;
2326 rb_link_node(&set
->rb_node
, parent
, p
);
2327 rb_insert_color(&set
->rb_node
, root_node
);
2328 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2329 spin_unlock(&inode
->i_lock
);
2332 rb_replace_node(parent
, &set
->rb_node
, root_node
);
2333 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2334 list_del(&entry
->lru
);
2335 spin_unlock(&inode
->i_lock
);
2336 nfs_access_free_entry(entry
);
2339 void nfs_access_add_cache(struct inode
*inode
, struct nfs_access_entry
*set
)
2341 struct nfs_access_entry
*cache
= kmalloc(sizeof(*cache
), GFP_KERNEL
);
2344 RB_CLEAR_NODE(&cache
->rb_node
);
2345 cache
->cred
= get_rpccred(set
->cred
);
2346 cache
->mask
= set
->mask
;
2348 /* The above field assignments must be visible
2349 * before this item appears on the lru. We cannot easily
2350 * use rcu_assign_pointer, so just force the memory barrier.
2353 nfs_access_add_rbtree(inode
, cache
);
2355 /* Update accounting */
2356 smp_mb__before_atomic();
2357 atomic_long_inc(&nfs_access_nr_entries
);
2358 smp_mb__after_atomic();
2360 /* Add inode to global LRU list */
2361 if (!test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
)) {
2362 spin_lock(&nfs_access_lru_lock
);
2363 if (!test_and_set_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
2364 list_add_tail(&NFS_I(inode
)->access_cache_inode_lru
,
2365 &nfs_access_lru_list
);
2366 spin_unlock(&nfs_access_lru_lock
);
2368 nfs_access_cache_enforce_limit();
2370 EXPORT_SYMBOL_GPL(nfs_access_add_cache
);
2372 #define NFS_MAY_READ (NFS4_ACCESS_READ)
2373 #define NFS_MAY_WRITE (NFS4_ACCESS_MODIFY | \
2374 NFS4_ACCESS_EXTEND | \
2376 #define NFS_FILE_MAY_WRITE (NFS4_ACCESS_MODIFY | \
2378 #define NFS_DIR_MAY_WRITE NFS_MAY_WRITE
2379 #define NFS_MAY_LOOKUP (NFS4_ACCESS_LOOKUP)
2380 #define NFS_MAY_EXECUTE (NFS4_ACCESS_EXECUTE)
2382 nfs_access_calc_mask(u32 access_result
, umode_t umode
)
2386 if (access_result
& NFS_MAY_READ
)
2388 if (S_ISDIR(umode
)) {
2389 if ((access_result
& NFS_DIR_MAY_WRITE
) == NFS_DIR_MAY_WRITE
)
2391 if ((access_result
& NFS_MAY_LOOKUP
) == NFS_MAY_LOOKUP
)
2393 } else if (S_ISREG(umode
)) {
2394 if ((access_result
& NFS_FILE_MAY_WRITE
) == NFS_FILE_MAY_WRITE
)
2396 if ((access_result
& NFS_MAY_EXECUTE
) == NFS_MAY_EXECUTE
)
2398 } else if (access_result
& NFS_MAY_WRITE
)
2403 void nfs_access_set_mask(struct nfs_access_entry
*entry
, u32 access_result
)
2405 entry
->mask
= access_result
;
2407 EXPORT_SYMBOL_GPL(nfs_access_set_mask
);
2409 static int nfs_do_access(struct inode
*inode
, struct rpc_cred
*cred
, int mask
)
2411 struct nfs_access_entry cache
;
2412 bool may_block
= (mask
& MAY_NOT_BLOCK
) == 0;
2416 trace_nfs_access_enter(inode
);
2418 status
= nfs_access_get_cached_rcu(inode
, cred
, &cache
);
2420 status
= nfs_access_get_cached(inode
, cred
, &cache
, may_block
);
2428 /* Be clever: ask server to check for all possible rights */
2429 cache
.mask
= NFS_MAY_LOOKUP
| NFS_MAY_EXECUTE
2430 | NFS_MAY_WRITE
| NFS_MAY_READ
;
2432 status
= NFS_PROTO(inode
)->access(inode
, &cache
);
2434 if (status
== -ESTALE
) {
2435 nfs_zap_caches(inode
);
2436 if (!S_ISDIR(inode
->i_mode
))
2437 set_bit(NFS_INO_STALE
, &NFS_I(inode
)->flags
);
2441 nfs_access_add_cache(inode
, &cache
);
2443 cache_mask
= nfs_access_calc_mask(cache
.mask
, inode
->i_mode
);
2444 if ((mask
& ~cache_mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) != 0)
2447 trace_nfs_access_exit(inode
, status
);
2451 static int nfs_open_permission_mask(int openflags
)
2455 if (openflags
& __FMODE_EXEC
) {
2456 /* ONLY check exec rights */
2459 if ((openflags
& O_ACCMODE
) != O_WRONLY
)
2461 if ((openflags
& O_ACCMODE
) != O_RDONLY
)
2468 int nfs_may_open(struct inode
*inode
, struct rpc_cred
*cred
, int openflags
)
2470 return nfs_do_access(inode
, cred
, nfs_open_permission_mask(openflags
));
2472 EXPORT_SYMBOL_GPL(nfs_may_open
);
2474 static int nfs_execute_ok(struct inode
*inode
, int mask
)
2476 struct nfs_server
*server
= NFS_SERVER(inode
);
2479 if (nfs_check_cache_invalid(inode
, NFS_INO_INVALID_ACCESS
)) {
2480 if (mask
& MAY_NOT_BLOCK
)
2482 ret
= __nfs_revalidate_inode(server
, inode
);
2484 if (ret
== 0 && !execute_ok(inode
))
2489 int nfs_permission(struct inode
*inode
, int mask
)
2491 struct rpc_cred
*cred
;
2494 nfs_inc_stats(inode
, NFSIOS_VFSACCESS
);
2496 if ((mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) == 0)
2498 /* Is this sys_access() ? */
2499 if (mask
& (MAY_ACCESS
| MAY_CHDIR
))
2502 switch (inode
->i_mode
& S_IFMT
) {
2506 if ((mask
& MAY_OPEN
) &&
2507 nfs_server_capable(inode
, NFS_CAP_ATOMIC_OPEN
))
2512 * Optimize away all write operations, since the server
2513 * will check permissions when we perform the op.
2515 if ((mask
& MAY_WRITE
) && !(mask
& MAY_READ
))
2520 if (!NFS_PROTO(inode
)->access
)
2523 /* Always try fast lookups first */
2525 cred
= rpc_lookup_cred_nonblock();
2527 res
= nfs_do_access(inode
, cred
, mask
|MAY_NOT_BLOCK
);
2529 res
= PTR_ERR(cred
);
2531 if (res
== -ECHILD
&& !(mask
& MAY_NOT_BLOCK
)) {
2532 /* Fast lookup failed, try the slow way */
2533 cred
= rpc_lookup_cred();
2534 if (!IS_ERR(cred
)) {
2535 res
= nfs_do_access(inode
, cred
, mask
);
2538 res
= PTR_ERR(cred
);
2541 if (!res
&& (mask
& MAY_EXEC
))
2542 res
= nfs_execute_ok(inode
, mask
);
2544 dfprintk(VFS
, "NFS: permission(%s/%lu), mask=0x%x, res=%d\n",
2545 inode
->i_sb
->s_id
, inode
->i_ino
, mask
, res
);
2548 if (mask
& MAY_NOT_BLOCK
)
2551 res
= nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
2553 res
= generic_permission(inode
, mask
);
2556 EXPORT_SYMBOL_GPL(nfs_permission
);
2560 * version-control: t
2561 * kept-new-versions: 5