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_shared
= 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
{
152 struct nfs_cache_array_entry array
[0];
155 typedef int (*decode_dirent_t
)(struct xdr_stream
*, struct nfs_entry
*, int);
159 struct dir_context
*ctx
;
160 unsigned long page_index
;
163 loff_t current_index
;
164 decode_dirent_t decode
;
166 unsigned long timestamp
;
167 unsigned long gencount
;
168 unsigned int cache_entry_index
;
171 } nfs_readdir_descriptor_t
;
174 * The caller is responsible for calling nfs_readdir_release_array(page)
177 struct nfs_cache_array
*nfs_readdir_get_array(struct page
*page
)
181 return ERR_PTR(-EIO
);
184 return ERR_PTR(-ENOMEM
);
189 void nfs_readdir_release_array(struct page
*page
)
195 * we are freeing strings created by nfs_add_to_readdir_array()
198 void nfs_readdir_clear_array(struct page
*page
)
200 struct nfs_cache_array
*array
;
203 array
= kmap_atomic(page
);
204 if (atomic_dec_and_test(&array
->refcount
))
205 for (i
= 0; i
< array
->size
; i
++)
206 kfree(array
->array
[i
].string
.name
);
207 kunmap_atomic(array
);
210 static bool grab_page(struct page
*page
)
212 struct nfs_cache_array
*array
= kmap_atomic(page
);
213 bool res
= atomic_inc_not_zero(&array
->refcount
);
214 kunmap_atomic(array
);
219 * the caller is responsible for freeing qstr.name
220 * when called by nfs_readdir_add_to_array, the strings will be freed in
221 * nfs_clear_readdir_array()
224 int nfs_readdir_make_qstr(struct qstr
*string
, const char *name
, unsigned int len
)
227 string
->name
= kmemdup(name
, len
, GFP_KERNEL
);
228 if (string
->name
== NULL
)
231 * Avoid a kmemleak false positive. The pointer to the name is stored
232 * in a page cache page which kmemleak does not scan.
234 kmemleak_not_leak(string
->name
);
235 string
->hash
= full_name_hash(name
, len
);
240 int nfs_readdir_add_to_array(struct nfs_entry
*entry
, struct page
*page
)
242 struct nfs_cache_array
*array
= nfs_readdir_get_array(page
);
243 struct nfs_cache_array_entry
*cache_entry
;
247 return PTR_ERR(array
);
249 cache_entry
= &array
->array
[array
->size
];
251 /* Check that this entry lies within the page bounds */
253 if ((char *)&cache_entry
[1] - (char *)page_address(page
) > PAGE_SIZE
)
256 cache_entry
->cookie
= entry
->prev_cookie
;
257 cache_entry
->ino
= entry
->ino
;
258 cache_entry
->d_type
= entry
->d_type
;
259 ret
= nfs_readdir_make_qstr(&cache_entry
->string
, entry
->name
, entry
->len
);
262 array
->last_cookie
= entry
->cookie
;
265 array
->eof_index
= array
->size
;
267 nfs_readdir_release_array(page
);
272 int nfs_readdir_search_for_pos(struct nfs_cache_array
*array
, nfs_readdir_descriptor_t
*desc
)
274 loff_t diff
= desc
->ctx
->pos
- desc
->current_index
;
279 if (diff
>= array
->size
) {
280 if (array
->eof_index
>= 0)
285 index
= (unsigned int)diff
;
286 *desc
->dir_cookie
= array
->array
[index
].cookie
;
287 desc
->cache_entry_index
= index
;
295 nfs_readdir_inode_mapping_valid(struct nfs_inode
*nfsi
)
297 if (nfsi
->cache_validity
& (NFS_INO_INVALID_ATTR
|NFS_INO_INVALID_DATA
))
300 return !test_bit(NFS_INO_INVALIDATING
, &nfsi
->flags
);
304 int nfs_readdir_search_for_cookie(struct nfs_cache_array
*array
, nfs_readdir_descriptor_t
*desc
)
308 int status
= -EAGAIN
;
310 for (i
= 0; i
< array
->size
; i
++) {
311 if (array
->array
[i
].cookie
== *desc
->dir_cookie
) {
312 struct nfs_inode
*nfsi
= NFS_I(file_inode(desc
->file
));
313 struct nfs_open_dir_context
*ctx
= desc
->file
->private_data
;
315 new_pos
= desc
->current_index
+ i
;
316 if (ctx
->attr_gencount
!= nfsi
->attr_gencount
||
317 !nfs_readdir_inode_mapping_valid(nfsi
)) {
319 ctx
->attr_gencount
= nfsi
->attr_gencount
;
320 } else if (new_pos
< desc
->ctx
->pos
) {
322 && ctx
->dup_cookie
== *desc
->dir_cookie
) {
323 if (printk_ratelimit()) {
324 pr_notice("NFS: directory %pD2 contains a readdir loop."
325 "Please contact your server vendor. "
326 "The file: %.*s has duplicate cookie %llu\n",
327 desc
->file
, array
->array
[i
].string
.len
,
328 array
->array
[i
].string
.name
, *desc
->dir_cookie
);
333 ctx
->dup_cookie
= *desc
->dir_cookie
;
336 desc
->ctx
->pos
= new_pos
;
337 desc
->cache_entry_index
= i
;
341 if (array
->eof_index
>= 0) {
342 status
= -EBADCOOKIE
;
343 if (*desc
->dir_cookie
== array
->last_cookie
)
351 int nfs_readdir_search_array(nfs_readdir_descriptor_t
*desc
)
353 struct nfs_cache_array
*array
;
356 array
= nfs_readdir_get_array(desc
->page
);
358 status
= PTR_ERR(array
);
362 if (*desc
->dir_cookie
== 0)
363 status
= nfs_readdir_search_for_pos(array
, desc
);
365 status
= nfs_readdir_search_for_cookie(array
, desc
);
367 if (status
== -EAGAIN
) {
368 desc
->last_cookie
= array
->last_cookie
;
369 desc
->current_index
+= array
->size
;
372 nfs_readdir_release_array(desc
->page
);
377 /* Fill a page with xdr information before transferring to the cache page */
379 int nfs_readdir_xdr_filler(struct page
**pages
, nfs_readdir_descriptor_t
*desc
,
380 struct nfs_entry
*entry
, struct file
*file
, struct inode
*inode
)
382 struct nfs_open_dir_context
*ctx
= file
->private_data
;
383 struct rpc_cred
*cred
= ctx
->cred
;
384 unsigned long timestamp
, gencount
;
389 gencount
= nfs_inc_attr_generation_counter();
390 error
= NFS_PROTO(inode
)->readdir(file_dentry(file
), cred
, entry
->cookie
, pages
,
391 NFS_SERVER(inode
)->dtsize
, desc
->plus
);
393 /* We requested READDIRPLUS, but the server doesn't grok it */
394 if (error
== -ENOTSUPP
&& desc
->plus
) {
395 NFS_SERVER(inode
)->caps
&= ~NFS_CAP_READDIRPLUS
;
396 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
402 desc
->timestamp
= timestamp
;
403 desc
->gencount
= gencount
;
408 static int xdr_decode(nfs_readdir_descriptor_t
*desc
,
409 struct nfs_entry
*entry
, struct xdr_stream
*xdr
)
413 error
= desc
->decode(xdr
, entry
, desc
->plus
);
416 entry
->fattr
->time_start
= desc
->timestamp
;
417 entry
->fattr
->gencount
= desc
->gencount
;
421 /* Match file and dirent using either filehandle or fileid
422 * Note: caller is responsible for checking the fsid
425 int nfs_same_file(struct dentry
*dentry
, struct nfs_entry
*entry
)
427 struct nfs_inode
*nfsi
;
429 if (d_really_is_negative(dentry
))
432 nfsi
= NFS_I(d_inode(dentry
));
433 if (entry
->fattr
->fileid
== nfsi
->fileid
)
435 if (nfs_compare_fh(entry
->fh
, &nfsi
->fh
) == 0)
441 bool nfs_use_readdirplus(struct inode
*dir
, struct dir_context
*ctx
)
443 if (!nfs_server_capable(dir
, NFS_CAP_READDIRPLUS
))
445 if (test_and_clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(dir
)->flags
))
453 * This function is called by the lookup code to request the use of
454 * readdirplus to accelerate any future lookups in the same
458 void nfs_advise_use_readdirplus(struct inode
*dir
)
460 set_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(dir
)->flags
);
464 * This function is mainly for use by nfs_getattr().
466 * If this is an 'ls -l', we want to force use of readdirplus.
467 * Do this by checking if there is an active file descriptor
468 * and calling nfs_advise_use_readdirplus, then forcing a
471 void nfs_force_use_readdirplus(struct inode
*dir
)
473 if (!list_empty(&NFS_I(dir
)->open_files
)) {
474 nfs_advise_use_readdirplus(dir
);
475 nfs_zap_mapping(dir
, dir
->i_mapping
);
480 void nfs_prime_dcache(struct dentry
*parent
, struct nfs_entry
*entry
)
482 struct qstr filename
= QSTR_INIT(entry
->name
, entry
->len
);
483 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq
);
484 struct dentry
*dentry
;
485 struct dentry
*alias
;
486 struct inode
*dir
= d_inode(parent
);
490 if (!(entry
->fattr
->valid
& NFS_ATTR_FATTR_FILEID
))
492 if (!(entry
->fattr
->valid
& NFS_ATTR_FATTR_FSID
))
494 if (filename
.name
[0] == '.') {
495 if (filename
.len
== 1)
497 if (filename
.len
== 2 && filename
.name
[1] == '.')
500 filename
.hash
= full_name_hash(filename
.name
, filename
.len
);
502 dentry
= d_lookup(parent
, &filename
);
505 dentry
= d_alloc_parallel(parent
, &filename
, &wq
);
509 if (!d_in_lookup(dentry
)) {
510 /* Is there a mountpoint here? If so, just exit */
511 if (!nfs_fsid_equal(&NFS_SB(dentry
->d_sb
)->fsid
,
512 &entry
->fattr
->fsid
))
514 if (nfs_same_file(dentry
, entry
)) {
515 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
516 status
= nfs_refresh_inode(d_inode(dentry
), entry
->fattr
);
518 nfs_setsecurity(d_inode(dentry
), entry
->fattr
, entry
->label
);
521 d_invalidate(dentry
);
528 inode
= nfs_fhget(dentry
->d_sb
, entry
->fh
, entry
->fattr
, entry
->label
);
529 alias
= d_splice_alias(inode
, dentry
);
530 d_lookup_done(dentry
);
537 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
542 /* Perform conversion from xdr to cache array */
544 int nfs_readdir_page_filler(nfs_readdir_descriptor_t
*desc
, struct nfs_entry
*entry
,
545 struct page
**xdr_pages
, struct page
*page
, unsigned int buflen
)
547 struct xdr_stream stream
;
549 struct page
*scratch
;
550 struct nfs_cache_array
*array
;
551 unsigned int count
= 0;
554 scratch
= alloc_page(GFP_KERNEL
);
561 xdr_init_decode_pages(&stream
, &buf
, xdr_pages
, buflen
);
562 xdr_set_scratch_buffer(&stream
, page_address(scratch
), PAGE_SIZE
);
565 status
= xdr_decode(desc
, entry
, &stream
);
567 if (status
== -EAGAIN
)
575 nfs_prime_dcache(file_dentry(desc
->file
), entry
);
577 status
= nfs_readdir_add_to_array(entry
, page
);
580 } while (!entry
->eof
);
583 if (count
== 0 || (status
== -EBADCOOKIE
&& entry
->eof
!= 0)) {
584 array
= nfs_readdir_get_array(page
);
585 if (!IS_ERR(array
)) {
586 array
->eof_index
= array
->size
;
588 nfs_readdir_release_array(page
);
590 status
= PTR_ERR(array
);
598 void nfs_readdir_free_pages(struct page
**pages
, unsigned int npages
)
601 for (i
= 0; i
< npages
; i
++)
606 * nfs_readdir_large_page will allocate pages that must be freed with a call
607 * to nfs_readdir_free_pagearray
610 int nfs_readdir_alloc_pages(struct page
**pages
, unsigned int npages
)
614 for (i
= 0; i
< npages
; i
++) {
615 struct page
*page
= alloc_page(GFP_KERNEL
);
623 nfs_readdir_free_pages(pages
, i
);
628 int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t
*desc
, struct page
*page
, struct inode
*inode
)
630 struct page
*pages
[NFS_MAX_READDIR_PAGES
];
631 struct nfs_entry entry
;
632 struct file
*file
= desc
->file
;
633 struct nfs_cache_array
*array
;
634 int status
= -ENOMEM
;
635 unsigned int array_size
= ARRAY_SIZE(pages
);
637 entry
.prev_cookie
= 0;
638 entry
.cookie
= desc
->last_cookie
;
640 entry
.fh
= nfs_alloc_fhandle();
641 entry
.fattr
= nfs_alloc_fattr();
642 entry
.server
= NFS_SERVER(inode
);
643 if (entry
.fh
== NULL
|| entry
.fattr
== NULL
)
646 entry
.label
= nfs4_label_alloc(NFS_SERVER(inode
), GFP_NOWAIT
);
647 if (IS_ERR(entry
.label
)) {
648 status
= PTR_ERR(entry
.label
);
652 array
= nfs_readdir_get_array(page
);
654 status
= PTR_ERR(array
);
657 memset(array
, 0, sizeof(struct nfs_cache_array
));
658 atomic_set(&array
->refcount
, 1);
659 array
->eof_index
= -1;
661 status
= nfs_readdir_alloc_pages(pages
, array_size
);
663 goto out_release_array
;
666 status
= nfs_readdir_xdr_filler(pages
, desc
, &entry
, file
, inode
);
671 status
= nfs_readdir_page_filler(desc
, &entry
, pages
, page
, pglen
);
673 if (status
== -ENOSPC
)
677 } while (array
->eof_index
< 0);
679 nfs_readdir_free_pages(pages
, array_size
);
681 nfs_readdir_release_array(page
);
683 nfs4_label_free(entry
.label
);
685 nfs_free_fattr(entry
.fattr
);
686 nfs_free_fhandle(entry
.fh
);
691 * Now we cache directories properly, by converting xdr information
692 * to an array that can be used for lookups later. This results in
693 * fewer cache pages, since we can store more information on each page.
694 * We only need to convert from xdr once so future lookups are much simpler
697 int nfs_readdir_filler(nfs_readdir_descriptor_t
*desc
, struct page
* page
)
699 struct inode
*inode
= file_inode(desc
->file
);
702 ret
= nfs_readdir_xdr_to_array(desc
, page
, inode
);
705 SetPageUptodate(page
);
707 if (invalidate_inode_pages2_range(inode
->i_mapping
, page
->index
+ 1, -1) < 0) {
708 /* Should never happen */
709 nfs_zap_mapping(inode
, inode
->i_mapping
);
719 void cache_page_release(nfs_readdir_descriptor_t
*desc
)
721 nfs_readdir_clear_array(desc
->page
);
722 put_page(desc
->page
);
727 struct page
*get_cache_page(nfs_readdir_descriptor_t
*desc
)
732 page
= read_cache_page(file_inode(desc
->file
)->i_mapping
,
733 desc
->page_index
, (filler_t
*)nfs_readdir_filler
, desc
);
734 if (IS_ERR(page
) || grab_page(page
))
742 * Returns 0 if desc->dir_cookie was found on page desc->page_index
745 int find_cache_page(nfs_readdir_descriptor_t
*desc
)
749 desc
->page
= get_cache_page(desc
);
750 if (IS_ERR(desc
->page
))
751 return PTR_ERR(desc
->page
);
753 res
= nfs_readdir_search_array(desc
);
755 cache_page_release(desc
);
759 /* Search for desc->dir_cookie from the beginning of the page cache */
761 int readdir_search_pagecache(nfs_readdir_descriptor_t
*desc
)
765 if (desc
->page_index
== 0) {
766 desc
->current_index
= 0;
767 desc
->last_cookie
= 0;
770 res
= find_cache_page(desc
);
771 } while (res
== -EAGAIN
);
776 * Once we've found the start of the dirent within a page: fill 'er up...
779 int nfs_do_filldir(nfs_readdir_descriptor_t
*desc
)
781 struct file
*file
= desc
->file
;
784 struct nfs_cache_array
*array
= NULL
;
785 struct nfs_open_dir_context
*ctx
= file
->private_data
;
787 array
= nfs_readdir_get_array(desc
->page
);
789 res
= PTR_ERR(array
);
793 for (i
= desc
->cache_entry_index
; i
< array
->size
; i
++) {
794 struct nfs_cache_array_entry
*ent
;
796 ent
= &array
->array
[i
];
797 if (!dir_emit(desc
->ctx
, ent
->string
.name
, ent
->string
.len
,
798 nfs_compat_user_ino64(ent
->ino
), ent
->d_type
)) {
803 if (i
< (array
->size
-1))
804 *desc
->dir_cookie
= array
->array
[i
+1].cookie
;
806 *desc
->dir_cookie
= array
->last_cookie
;
810 if (array
->eof_index
>= 0)
813 nfs_readdir_release_array(desc
->page
);
815 cache_page_release(desc
);
816 dfprintk(DIRCACHE
, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n",
817 (unsigned long long)*desc
->dir_cookie
, res
);
822 * If we cannot find a cookie in our cache, we suspect that this is
823 * because it points to a deleted file, so we ask the server to return
824 * whatever it thinks is the next entry. We then feed this to filldir.
825 * If all goes well, we should then be able to find our way round the
826 * cache on the next call to readdir_search_pagecache();
828 * NOTE: we cannot add the anonymous page to the pagecache because
829 * the data it contains might not be page aligned. Besides,
830 * we should already have a complete representation of the
831 * directory in the page cache by the time we get here.
834 int uncached_readdir(nfs_readdir_descriptor_t
*desc
)
836 struct page
*page
= NULL
;
838 struct inode
*inode
= file_inode(desc
->file
);
839 struct nfs_open_dir_context
*ctx
= desc
->file
->private_data
;
841 dfprintk(DIRCACHE
, "NFS: uncached_readdir() searching for cookie %Lu\n",
842 (unsigned long long)*desc
->dir_cookie
);
844 page
= alloc_page(GFP_HIGHUSER
);
850 desc
->page_index
= 0;
851 desc
->last_cookie
= *desc
->dir_cookie
;
855 status
= nfs_readdir_xdr_to_array(desc
, page
, inode
);
859 status
= nfs_do_filldir(desc
);
862 dfprintk(DIRCACHE
, "NFS: %s: returns %d\n",
866 cache_page_release(desc
);
870 static bool nfs_dir_mapping_need_revalidate(struct inode
*dir
)
872 struct nfs_inode
*nfsi
= NFS_I(dir
);
874 if (nfs_attribute_cache_expired(dir
))
876 if (nfsi
->cache_validity
& NFS_INO_INVALID_DATA
)
881 /* The file offset position represents the dirent entry number. A
882 last cookie cache takes care of the common case of reading the
885 static int nfs_readdir(struct file
*file
, struct dir_context
*ctx
)
887 struct dentry
*dentry
= file_dentry(file
);
888 struct inode
*inode
= d_inode(dentry
);
889 nfs_readdir_descriptor_t my_desc
,
891 struct nfs_open_dir_context
*dir_ctx
= file
->private_data
;
894 dfprintk(FILE, "NFS: readdir(%pD2) starting at cookie %llu\n",
895 file
, (long long)ctx
->pos
);
896 nfs_inc_stats(inode
, NFSIOS_VFSGETDENTS
);
899 * ctx->pos points to the dirent entry number.
900 * *desc->dir_cookie has the cookie for the next entry. We have
901 * to either find the entry with the appropriate number or
902 * revalidate the cookie.
904 memset(desc
, 0, sizeof(*desc
));
908 desc
->dir_cookie
= &dir_ctx
->dir_cookie
;
909 desc
->decode
= NFS_PROTO(inode
)->decode_dirent
;
910 desc
->plus
= nfs_use_readdirplus(inode
, ctx
) ? 1 : 0;
912 if (ctx
->pos
== 0 || nfs_dir_mapping_need_revalidate(inode
))
913 res
= nfs_revalidate_mapping(inode
, file
->f_mapping
);
918 res
= readdir_search_pagecache(desc
);
920 if (res
== -EBADCOOKIE
) {
922 /* This means either end of directory */
923 if (*desc
->dir_cookie
&& desc
->eof
== 0) {
924 /* Or that the server has 'lost' a cookie */
925 res
= uncached_readdir(desc
);
931 if (res
== -ETOOSMALL
&& desc
->plus
) {
932 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
933 nfs_zap_caches(inode
);
934 desc
->page_index
= 0;
942 res
= nfs_do_filldir(desc
);
945 } while (!desc
->eof
);
949 dfprintk(FILE, "NFS: readdir(%pD2) returns %d\n", file
, res
);
953 static loff_t
nfs_llseek_dir(struct file
*filp
, loff_t offset
, int whence
)
955 struct nfs_open_dir_context
*dir_ctx
= filp
->private_data
;
957 dfprintk(FILE, "NFS: llseek dir(%pD2, %lld, %d)\n",
958 filp
, offset
, whence
);
962 offset
+= filp
->f_pos
;
969 if (offset
!= filp
->f_pos
) {
970 filp
->f_pos
= offset
;
971 dir_ctx
->dir_cookie
= 0;
978 * All directory operations under NFS are synchronous, so fsync()
979 * is a dummy operation.
981 static int nfs_fsync_dir(struct file
*filp
, loff_t start
, loff_t end
,
984 struct inode
*inode
= file_inode(filp
);
986 dfprintk(FILE, "NFS: fsync dir(%pD2) datasync %d\n", filp
, datasync
);
989 nfs_inc_stats(inode
, NFSIOS_VFSFSYNC
);
995 * nfs_force_lookup_revalidate - Mark the directory as having changed
996 * @dir - pointer to directory inode
998 * This forces the revalidation code in nfs_lookup_revalidate() to do a
999 * full lookup on all child dentries of 'dir' whenever a change occurs
1000 * on the server that might have invalidated our dcache.
1002 * The caller should be holding dir->i_lock
1004 void nfs_force_lookup_revalidate(struct inode
*dir
)
1006 NFS_I(dir
)->cache_change_attribute
++;
1008 EXPORT_SYMBOL_GPL(nfs_force_lookup_revalidate
);
1011 * A check for whether or not the parent directory has changed.
1012 * In the case it has, we assume that the dentries are untrustworthy
1013 * and may need to be looked up again.
1014 * If rcu_walk prevents us from performing a full check, return 0.
1016 static int nfs_check_verifier(struct inode
*dir
, struct dentry
*dentry
,
1021 if (IS_ROOT(dentry
))
1023 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONE
)
1025 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
1027 /* Revalidate nfsi->cache_change_attribute before we declare a match */
1029 ret
= nfs_revalidate_inode_rcu(NFS_SERVER(dir
), dir
);
1031 ret
= nfs_revalidate_inode(NFS_SERVER(dir
), dir
);
1034 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
1040 * Use intent information to check whether or not we're going to do
1041 * an O_EXCL create using this path component.
1043 static int nfs_is_exclusive_create(struct inode
*dir
, unsigned int flags
)
1045 if (NFS_PROTO(dir
)->version
== 2)
1047 return flags
& LOOKUP_EXCL
;
1051 * Inode and filehandle revalidation for lookups.
1053 * We force revalidation in the cases where the VFS sets LOOKUP_REVAL,
1054 * or if the intent information indicates that we're about to open this
1055 * particular file and the "nocto" mount flag is not set.
1059 int nfs_lookup_verify_inode(struct inode
*inode
, unsigned int flags
)
1061 struct nfs_server
*server
= NFS_SERVER(inode
);
1064 if (IS_AUTOMOUNT(inode
))
1066 /* VFS wants an on-the-wire revalidation */
1067 if (flags
& LOOKUP_REVAL
)
1069 /* This is an open(2) */
1070 if ((flags
& LOOKUP_OPEN
) && !(server
->flags
& NFS_MOUNT_NOCTO
) &&
1071 (S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
)))
1074 return (inode
->i_nlink
== 0) ? -ENOENT
: 0;
1076 if (flags
& LOOKUP_RCU
)
1078 ret
= __nfs_revalidate_inode(server
, inode
);
1085 * We judge how long we want to trust negative
1086 * dentries by looking at the parent inode mtime.
1088 * If parent mtime has changed, we revalidate, else we wait for a
1089 * period corresponding to the parent's attribute cache timeout value.
1091 * If LOOKUP_RCU prevents us from performing a full check, return 1
1092 * suggesting a reval is needed.
1095 int nfs_neg_need_reval(struct inode
*dir
, struct dentry
*dentry
,
1098 /* Don't revalidate a negative dentry if we're creating a new file */
1099 if (flags
& LOOKUP_CREATE
)
1101 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONEG
)
1103 return !nfs_check_verifier(dir
, dentry
, flags
& LOOKUP_RCU
);
1107 * This is called every time the dcache has a lookup hit,
1108 * and we should check whether we can really trust that
1111 * NOTE! The hit can be a negative hit too, don't assume
1114 * If the parent directory is seen to have changed, we throw out the
1115 * cached dentry and do a new lookup.
1117 static int nfs_lookup_revalidate(struct dentry
*dentry
, unsigned int flags
)
1120 struct inode
*inode
;
1121 struct dentry
*parent
;
1122 struct nfs_fh
*fhandle
= NULL
;
1123 struct nfs_fattr
*fattr
= NULL
;
1124 struct nfs4_label
*label
= NULL
;
1127 if (flags
& LOOKUP_RCU
) {
1128 parent
= ACCESS_ONCE(dentry
->d_parent
);
1129 dir
= d_inode_rcu(parent
);
1133 parent
= dget_parent(dentry
);
1134 dir
= d_inode(parent
);
1136 nfs_inc_stats(dir
, NFSIOS_DENTRYREVALIDATE
);
1137 inode
= d_inode(dentry
);
1140 if (nfs_neg_need_reval(dir
, dentry
, flags
)) {
1141 if (flags
& LOOKUP_RCU
)
1145 goto out_valid_noent
;
1148 if (is_bad_inode(inode
)) {
1149 if (flags
& LOOKUP_RCU
)
1151 dfprintk(LOOKUPCACHE
, "%s: %pd2 has dud inode\n",
1156 if (NFS_PROTO(dir
)->have_delegation(inode
, FMODE_READ
))
1157 goto out_set_verifier
;
1159 /* Force a full look up iff the parent directory has changed */
1160 if (!nfs_is_exclusive_create(dir
, flags
) &&
1161 nfs_check_verifier(dir
, dentry
, flags
& LOOKUP_RCU
)) {
1163 if (nfs_lookup_verify_inode(inode
, flags
)) {
1164 if (flags
& LOOKUP_RCU
)
1166 goto out_zap_parent
;
1171 if (flags
& LOOKUP_RCU
)
1174 if (NFS_STALE(inode
))
1178 fhandle
= nfs_alloc_fhandle();
1179 fattr
= nfs_alloc_fattr();
1180 if (fhandle
== NULL
|| fattr
== NULL
)
1183 label
= nfs4_label_alloc(NFS_SERVER(inode
), GFP_NOWAIT
);
1187 trace_nfs_lookup_revalidate_enter(dir
, dentry
, flags
);
1188 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
, label
);
1189 trace_nfs_lookup_revalidate_exit(dir
, dentry
, flags
, error
);
1192 if (nfs_compare_fh(NFS_FH(inode
), fhandle
))
1194 if ((error
= nfs_refresh_inode(inode
, fattr
)) != 0)
1197 nfs_setsecurity(inode
, fattr
, label
);
1199 nfs_free_fattr(fattr
);
1200 nfs_free_fhandle(fhandle
);
1201 nfs4_label_free(label
);
1204 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1206 /* Success: notify readdir to use READDIRPLUS */
1207 nfs_advise_use_readdirplus(dir
);
1209 if (flags
& LOOKUP_RCU
) {
1210 if (parent
!= ACCESS_ONCE(dentry
->d_parent
))
1214 dfprintk(LOOKUPCACHE
, "NFS: %s(%pd2) is valid\n",
1218 nfs_zap_caches(dir
);
1220 WARN_ON(flags
& LOOKUP_RCU
);
1221 nfs_free_fattr(fattr
);
1222 nfs_free_fhandle(fhandle
);
1223 nfs4_label_free(label
);
1224 nfs_mark_for_revalidate(dir
);
1225 if (inode
&& S_ISDIR(inode
->i_mode
)) {
1226 /* Purge readdir caches. */
1227 nfs_zap_caches(inode
);
1229 * We can't d_drop the root of a disconnected tree:
1230 * its d_hash is on the s_anon list and d_drop() would hide
1231 * it from shrink_dcache_for_unmount(), leading to busy
1232 * inodes on unmount and further oopses.
1234 if (IS_ROOT(dentry
))
1238 dfprintk(LOOKUPCACHE
, "NFS: %s(%pd2) is invalid\n",
1242 WARN_ON(flags
& LOOKUP_RCU
);
1243 nfs_free_fattr(fattr
);
1244 nfs_free_fhandle(fhandle
);
1245 nfs4_label_free(label
);
1247 dfprintk(LOOKUPCACHE
, "NFS: %s(%pd2) lookup returned error %d\n",
1248 __func__
, dentry
, error
);
1253 * A weaker form of d_revalidate for revalidating just the d_inode(dentry)
1254 * when we don't really care about the dentry name. This is called when a
1255 * pathwalk ends on a dentry that was not found via a normal lookup in the
1256 * parent dir (e.g.: ".", "..", procfs symlinks or mountpoint traversals).
1258 * In this situation, we just want to verify that the inode itself is OK
1259 * since the dentry might have changed on the server.
1261 static int nfs_weak_revalidate(struct dentry
*dentry
, unsigned int flags
)
1264 struct inode
*inode
= d_inode(dentry
);
1267 * I believe we can only get a negative dentry here in the case of a
1268 * procfs-style symlink. Just assume it's correct for now, but we may
1269 * eventually need to do something more here.
1272 dfprintk(LOOKUPCACHE
, "%s: %pd2 has negative inode\n",
1277 if (is_bad_inode(inode
)) {
1278 dfprintk(LOOKUPCACHE
, "%s: %pd2 has dud inode\n",
1283 error
= nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
1284 dfprintk(LOOKUPCACHE
, "NFS: %s: inode %lu is %s\n",
1285 __func__
, inode
->i_ino
, error
? "invalid" : "valid");
1290 * This is called from dput() when d_count is going to 0.
1292 static int nfs_dentry_delete(const struct dentry
*dentry
)
1294 dfprintk(VFS
, "NFS: dentry_delete(%pd2, %x)\n",
1295 dentry
, dentry
->d_flags
);
1297 /* Unhash any dentry with a stale inode */
1298 if (d_really_is_positive(dentry
) && NFS_STALE(d_inode(dentry
)))
1301 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1302 /* Unhash it, so that ->d_iput() would be called */
1305 if (!(dentry
->d_sb
->s_flags
& MS_ACTIVE
)) {
1306 /* Unhash it, so that ancestors of killed async unlink
1307 * files will be cleaned up during umount */
1314 /* Ensure that we revalidate inode->i_nlink */
1315 static void nfs_drop_nlink(struct inode
*inode
)
1317 spin_lock(&inode
->i_lock
);
1318 /* drop the inode if we're reasonably sure this is the last link */
1319 if (inode
->i_nlink
== 1)
1321 NFS_I(inode
)->cache_validity
|= NFS_INO_INVALID_ATTR
;
1322 spin_unlock(&inode
->i_lock
);
1326 * Called when the dentry loses inode.
1327 * We use it to clean up silly-renamed files.
1329 static void nfs_dentry_iput(struct dentry
*dentry
, struct inode
*inode
)
1331 if (S_ISDIR(inode
->i_mode
))
1332 /* drop any readdir cache as it could easily be old */
1333 NFS_I(inode
)->cache_validity
|= NFS_INO_INVALID_DATA
;
1335 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1336 nfs_complete_unlink(dentry
, inode
);
1337 nfs_drop_nlink(inode
);
1342 static void nfs_d_release(struct dentry
*dentry
)
1344 /* free cached devname value, if it survived that far */
1345 if (unlikely(dentry
->d_fsdata
)) {
1346 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
)
1349 kfree(dentry
->d_fsdata
);
1353 const struct dentry_operations nfs_dentry_operations
= {
1354 .d_revalidate
= nfs_lookup_revalidate
,
1355 .d_weak_revalidate
= nfs_weak_revalidate
,
1356 .d_delete
= nfs_dentry_delete
,
1357 .d_iput
= nfs_dentry_iput
,
1358 .d_automount
= nfs_d_automount
,
1359 .d_release
= nfs_d_release
,
1361 EXPORT_SYMBOL_GPL(nfs_dentry_operations
);
1363 struct dentry
*nfs_lookup(struct inode
*dir
, struct dentry
* dentry
, unsigned int flags
)
1366 struct dentry
*parent
;
1367 struct inode
*inode
= NULL
;
1368 struct nfs_fh
*fhandle
= NULL
;
1369 struct nfs_fattr
*fattr
= NULL
;
1370 struct nfs4_label
*label
= NULL
;
1373 dfprintk(VFS
, "NFS: lookup(%pd2)\n", dentry
);
1374 nfs_inc_stats(dir
, NFSIOS_VFSLOOKUP
);
1376 if (unlikely(dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
))
1377 return ERR_PTR(-ENAMETOOLONG
);
1380 * If we're doing an exclusive create, optimize away the lookup
1381 * but don't hash the dentry.
1383 if (nfs_is_exclusive_create(dir
, flags
))
1386 res
= ERR_PTR(-ENOMEM
);
1387 fhandle
= nfs_alloc_fhandle();
1388 fattr
= nfs_alloc_fattr();
1389 if (fhandle
== NULL
|| fattr
== NULL
)
1392 label
= nfs4_label_alloc(NFS_SERVER(dir
), GFP_NOWAIT
);
1396 parent
= dentry
->d_parent
;
1397 /* Protect against concurrent sillydeletes */
1398 trace_nfs_lookup_enter(dir
, dentry
, flags
);
1399 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
, label
);
1400 if (error
== -ENOENT
)
1403 res
= ERR_PTR(error
);
1404 goto out_unblock_sillyrename
;
1406 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
, label
);
1407 res
= ERR_CAST(inode
);
1409 goto out_unblock_sillyrename
;
1411 /* Success: notify readdir to use READDIRPLUS */
1412 nfs_advise_use_readdirplus(dir
);
1415 res
= d_splice_alias(inode
, dentry
);
1418 goto out_unblock_sillyrename
;
1421 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1422 out_unblock_sillyrename
:
1423 trace_nfs_lookup_exit(dir
, dentry
, flags
, error
);
1424 nfs4_label_free(label
);
1426 nfs_free_fattr(fattr
);
1427 nfs_free_fhandle(fhandle
);
1430 EXPORT_SYMBOL_GPL(nfs_lookup
);
1432 #if IS_ENABLED(CONFIG_NFS_V4)
1433 static int nfs4_lookup_revalidate(struct dentry
*, unsigned int);
1435 const struct dentry_operations nfs4_dentry_operations
= {
1436 .d_revalidate
= nfs4_lookup_revalidate
,
1437 .d_delete
= nfs_dentry_delete
,
1438 .d_iput
= nfs_dentry_iput
,
1439 .d_automount
= nfs_d_automount
,
1440 .d_release
= nfs_d_release
,
1442 EXPORT_SYMBOL_GPL(nfs4_dentry_operations
);
1444 static fmode_t
flags_to_mode(int flags
)
1446 fmode_t res
= (__force fmode_t
)flags
& FMODE_EXEC
;
1447 if ((flags
& O_ACCMODE
) != O_WRONLY
)
1449 if ((flags
& O_ACCMODE
) != O_RDONLY
)
1454 static struct nfs_open_context
*create_nfs_open_context(struct dentry
*dentry
, int open_flags
)
1456 return alloc_nfs_open_context(dentry
, flags_to_mode(open_flags
));
1459 static int do_open(struct inode
*inode
, struct file
*filp
)
1461 nfs_fscache_open_file(inode
, filp
);
1465 static int nfs_finish_open(struct nfs_open_context
*ctx
,
1466 struct dentry
*dentry
,
1467 struct file
*file
, unsigned open_flags
,
1472 err
= finish_open(file
, dentry
, do_open
, opened
);
1475 nfs_file_set_open_context(file
, ctx
);
1481 int nfs_atomic_open(struct inode
*dir
, struct dentry
*dentry
,
1482 struct file
*file
, unsigned open_flags
,
1483 umode_t mode
, int *opened
)
1485 struct nfs_open_context
*ctx
;
1487 struct iattr attr
= { .ia_valid
= ATTR_OPEN
};
1488 struct inode
*inode
;
1489 unsigned int lookup_flags
= 0;
1492 /* Expect a negative dentry */
1493 BUG_ON(d_inode(dentry
));
1495 dfprintk(VFS
, "NFS: atomic_open(%s/%lu), %pd\n",
1496 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1498 err
= nfs_check_flags(open_flags
);
1502 /* NFS only supports OPEN on regular files */
1503 if ((open_flags
& O_DIRECTORY
)) {
1504 if (!d_unhashed(dentry
)) {
1506 * Hashed negative dentry with O_DIRECTORY: dentry was
1507 * revalidated and is fine, no need to perform lookup
1512 lookup_flags
= LOOKUP_OPEN
|LOOKUP_DIRECTORY
;
1516 if (dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
)
1517 return -ENAMETOOLONG
;
1519 if (open_flags
& O_CREAT
) {
1520 attr
.ia_valid
|= ATTR_MODE
;
1521 attr
.ia_mode
= mode
& ~current_umask();
1523 if (open_flags
& O_TRUNC
) {
1524 attr
.ia_valid
|= ATTR_SIZE
;
1528 ctx
= create_nfs_open_context(dentry
, open_flags
);
1533 trace_nfs_atomic_open_enter(dir
, ctx
, open_flags
);
1534 inode
= NFS_PROTO(dir
)->open_context(dir
, ctx
, open_flags
, &attr
, opened
);
1535 if (IS_ERR(inode
)) {
1536 err
= PTR_ERR(inode
);
1537 trace_nfs_atomic_open_exit(dir
, ctx
, open_flags
, err
);
1538 put_nfs_open_context(ctx
);
1542 d_add(dentry
, NULL
);
1543 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1549 if (!(open_flags
& O_NOFOLLOW
))
1559 err
= nfs_finish_open(ctx
, ctx
->dentry
, file
, open_flags
, opened
);
1560 trace_nfs_atomic_open_exit(dir
, ctx
, open_flags
, err
);
1561 put_nfs_open_context(ctx
);
1566 res
= nfs_lookup(dir
, dentry
, lookup_flags
);
1571 return finish_no_open(file
, res
);
1573 EXPORT_SYMBOL_GPL(nfs_atomic_open
);
1575 static int nfs4_lookup_revalidate(struct dentry
*dentry
, unsigned int flags
)
1577 struct inode
*inode
;
1580 if (!(flags
& LOOKUP_OPEN
) || (flags
& LOOKUP_DIRECTORY
))
1582 if (d_mountpoint(dentry
))
1584 if (NFS_SB(dentry
->d_sb
)->caps
& NFS_CAP_ATOMIC_OPEN_V1
)
1587 inode
= d_inode(dentry
);
1589 /* We can't create new files in nfs_open_revalidate(), so we
1590 * optimize away revalidation of negative dentries.
1592 if (inode
== NULL
) {
1593 struct dentry
*parent
;
1596 if (flags
& LOOKUP_RCU
) {
1597 parent
= ACCESS_ONCE(dentry
->d_parent
);
1598 dir
= d_inode_rcu(parent
);
1602 parent
= dget_parent(dentry
);
1603 dir
= d_inode(parent
);
1605 if (!nfs_neg_need_reval(dir
, dentry
, flags
))
1607 else if (flags
& LOOKUP_RCU
)
1609 if (!(flags
& LOOKUP_RCU
))
1611 else if (parent
!= ACCESS_ONCE(dentry
->d_parent
))
1616 /* NFS only supports OPEN on regular files */
1617 if (!S_ISREG(inode
->i_mode
))
1619 /* We cannot do exclusive creation on a positive dentry */
1620 if (flags
& LOOKUP_EXCL
)
1623 /* Let f_op->open() actually open (and revalidate) the file */
1630 return nfs_lookup_revalidate(dentry
, flags
);
1633 #endif /* CONFIG_NFSV4 */
1636 * Code common to create, mkdir, and mknod.
1638 int nfs_instantiate(struct dentry
*dentry
, struct nfs_fh
*fhandle
,
1639 struct nfs_fattr
*fattr
,
1640 struct nfs4_label
*label
)
1642 struct dentry
*parent
= dget_parent(dentry
);
1643 struct inode
*dir
= d_inode(parent
);
1644 struct inode
*inode
;
1645 int error
= -EACCES
;
1649 /* We may have been initialized further down */
1650 if (d_really_is_positive(dentry
))
1652 if (fhandle
->size
== 0) {
1653 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
, NULL
);
1657 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1658 if (!(fattr
->valid
& NFS_ATTR_FATTR
)) {
1659 struct nfs_server
*server
= NFS_SB(dentry
->d_sb
);
1660 error
= server
->nfs_client
->rpc_ops
->getattr(server
, fhandle
, fattr
, NULL
);
1664 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
, label
);
1665 error
= PTR_ERR(inode
);
1668 d_add(dentry
, inode
);
1673 nfs_mark_for_revalidate(dir
);
1677 EXPORT_SYMBOL_GPL(nfs_instantiate
);
1680 * Following a failed create operation, we drop the dentry rather
1681 * than retain a negative dentry. This avoids a problem in the event
1682 * that the operation succeeded on the server, but an error in the
1683 * reply path made it appear to have failed.
1685 int nfs_create(struct inode
*dir
, struct dentry
*dentry
,
1686 umode_t mode
, bool excl
)
1689 int open_flags
= excl
? O_CREAT
| O_EXCL
: O_CREAT
;
1692 dfprintk(VFS
, "NFS: create(%s/%lu), %pd\n",
1693 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1695 attr
.ia_mode
= mode
;
1696 attr
.ia_valid
= ATTR_MODE
;
1698 trace_nfs_create_enter(dir
, dentry
, open_flags
);
1699 error
= NFS_PROTO(dir
)->create(dir
, dentry
, &attr
, open_flags
);
1700 trace_nfs_create_exit(dir
, dentry
, open_flags
, error
);
1708 EXPORT_SYMBOL_GPL(nfs_create
);
1711 * See comments for nfs_proc_create regarding failed operations.
1714 nfs_mknod(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
, dev_t rdev
)
1719 dfprintk(VFS
, "NFS: mknod(%s/%lu), %pd\n",
1720 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1722 attr
.ia_mode
= mode
;
1723 attr
.ia_valid
= ATTR_MODE
;
1725 trace_nfs_mknod_enter(dir
, dentry
);
1726 status
= NFS_PROTO(dir
)->mknod(dir
, dentry
, &attr
, rdev
);
1727 trace_nfs_mknod_exit(dir
, dentry
, status
);
1735 EXPORT_SYMBOL_GPL(nfs_mknod
);
1738 * See comments for nfs_proc_create regarding failed operations.
1740 int nfs_mkdir(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
)
1745 dfprintk(VFS
, "NFS: mkdir(%s/%lu), %pd\n",
1746 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1748 attr
.ia_valid
= ATTR_MODE
;
1749 attr
.ia_mode
= mode
| S_IFDIR
;
1751 trace_nfs_mkdir_enter(dir
, dentry
);
1752 error
= NFS_PROTO(dir
)->mkdir(dir
, dentry
, &attr
);
1753 trace_nfs_mkdir_exit(dir
, dentry
, error
);
1761 EXPORT_SYMBOL_GPL(nfs_mkdir
);
1763 static void nfs_dentry_handle_enoent(struct dentry
*dentry
)
1765 if (simple_positive(dentry
))
1769 int nfs_rmdir(struct inode
*dir
, struct dentry
*dentry
)
1773 dfprintk(VFS
, "NFS: rmdir(%s/%lu), %pd\n",
1774 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1776 trace_nfs_rmdir_enter(dir
, dentry
);
1777 if (d_really_is_positive(dentry
)) {
1778 down_write(&NFS_I(d_inode(dentry
))->rmdir_sem
);
1779 error
= NFS_PROTO(dir
)->rmdir(dir
, &dentry
->d_name
);
1780 /* Ensure the VFS deletes this inode */
1783 clear_nlink(d_inode(dentry
));
1786 nfs_dentry_handle_enoent(dentry
);
1788 up_write(&NFS_I(d_inode(dentry
))->rmdir_sem
);
1790 error
= NFS_PROTO(dir
)->rmdir(dir
, &dentry
->d_name
);
1791 trace_nfs_rmdir_exit(dir
, dentry
, error
);
1795 EXPORT_SYMBOL_GPL(nfs_rmdir
);
1798 * Remove a file after making sure there are no pending writes,
1799 * and after checking that the file has only one user.
1801 * We invalidate the attribute cache and free the inode prior to the operation
1802 * to avoid possible races if the server reuses the inode.
1804 static int nfs_safe_remove(struct dentry
*dentry
)
1806 struct inode
*dir
= d_inode(dentry
->d_parent
);
1807 struct inode
*inode
= d_inode(dentry
);
1810 dfprintk(VFS
, "NFS: safe_remove(%pd2)\n", dentry
);
1812 /* If the dentry was sillyrenamed, we simply call d_delete() */
1813 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1818 trace_nfs_remove_enter(dir
, dentry
);
1819 if (inode
!= NULL
) {
1820 NFS_PROTO(inode
)->return_delegation(inode
);
1821 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1823 nfs_drop_nlink(inode
);
1825 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1826 if (error
== -ENOENT
)
1827 nfs_dentry_handle_enoent(dentry
);
1828 trace_nfs_remove_exit(dir
, dentry
, error
);
1833 /* We do silly rename. In case sillyrename() returns -EBUSY, the inode
1834 * belongs to an active ".nfs..." file and we return -EBUSY.
1836 * If sillyrename() returns 0, we do nothing, otherwise we unlink.
1838 int nfs_unlink(struct inode
*dir
, struct dentry
*dentry
)
1841 int need_rehash
= 0;
1843 dfprintk(VFS
, "NFS: unlink(%s/%lu, %pd)\n", dir
->i_sb
->s_id
,
1844 dir
->i_ino
, dentry
);
1846 trace_nfs_unlink_enter(dir
, dentry
);
1847 spin_lock(&dentry
->d_lock
);
1848 if (d_count(dentry
) > 1) {
1849 spin_unlock(&dentry
->d_lock
);
1850 /* Start asynchronous writeout of the inode */
1851 write_inode_now(d_inode(dentry
), 0);
1852 error
= nfs_sillyrename(dir
, dentry
);
1855 if (!d_unhashed(dentry
)) {
1859 spin_unlock(&dentry
->d_lock
);
1860 error
= nfs_safe_remove(dentry
);
1861 if (!error
|| error
== -ENOENT
) {
1862 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1863 } else if (need_rehash
)
1866 trace_nfs_unlink_exit(dir
, dentry
, error
);
1869 EXPORT_SYMBOL_GPL(nfs_unlink
);
1872 * To create a symbolic link, most file systems instantiate a new inode,
1873 * add a page to it containing the path, then write it out to the disk
1874 * using prepare_write/commit_write.
1876 * Unfortunately the NFS client can't create the in-core inode first
1877 * because it needs a file handle to create an in-core inode (see
1878 * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the
1879 * symlink request has completed on the server.
1881 * So instead we allocate a raw page, copy the symname into it, then do
1882 * the SYMLINK request with the page as the buffer. If it succeeds, we
1883 * now have a new file handle and can instantiate an in-core NFS inode
1884 * and move the raw page into its mapping.
1886 int nfs_symlink(struct inode
*dir
, struct dentry
*dentry
, const char *symname
)
1891 unsigned int pathlen
= strlen(symname
);
1894 dfprintk(VFS
, "NFS: symlink(%s/%lu, %pd, %s)\n", dir
->i_sb
->s_id
,
1895 dir
->i_ino
, dentry
, symname
);
1897 if (pathlen
> PAGE_SIZE
)
1898 return -ENAMETOOLONG
;
1900 attr
.ia_mode
= S_IFLNK
| S_IRWXUGO
;
1901 attr
.ia_valid
= ATTR_MODE
;
1903 page
= alloc_page(GFP_USER
);
1907 kaddr
= page_address(page
);
1908 memcpy(kaddr
, symname
, pathlen
);
1909 if (pathlen
< PAGE_SIZE
)
1910 memset(kaddr
+ pathlen
, 0, PAGE_SIZE
- pathlen
);
1912 trace_nfs_symlink_enter(dir
, dentry
);
1913 error
= NFS_PROTO(dir
)->symlink(dir
, dentry
, page
, pathlen
, &attr
);
1914 trace_nfs_symlink_exit(dir
, dentry
, error
);
1916 dfprintk(VFS
, "NFS: symlink(%s/%lu, %pd, %s) error %d\n",
1917 dir
->i_sb
->s_id
, dir
->i_ino
,
1918 dentry
, symname
, error
);
1925 * No big deal if we can't add this page to the page cache here.
1926 * READLINK will get the missing page from the server if needed.
1928 if (!add_to_page_cache_lru(page
, d_inode(dentry
)->i_mapping
, 0,
1930 SetPageUptodate(page
);
1933 * add_to_page_cache_lru() grabs an extra page refcount.
1934 * Drop it here to avoid leaking this page later.
1942 EXPORT_SYMBOL_GPL(nfs_symlink
);
1945 nfs_link(struct dentry
*old_dentry
, struct inode
*dir
, struct dentry
*dentry
)
1947 struct inode
*inode
= d_inode(old_dentry
);
1950 dfprintk(VFS
, "NFS: link(%pd2 -> %pd2)\n",
1951 old_dentry
, dentry
);
1953 trace_nfs_link_enter(inode
, dir
, dentry
);
1954 NFS_PROTO(inode
)->return_delegation(inode
);
1957 error
= NFS_PROTO(dir
)->link(inode
, dir
, &dentry
->d_name
);
1960 d_add(dentry
, inode
);
1962 trace_nfs_link_exit(inode
, dir
, dentry
, error
);
1965 EXPORT_SYMBOL_GPL(nfs_link
);
1969 * FIXME: Some nfsds, like the Linux user space nfsd, may generate a
1970 * different file handle for the same inode after a rename (e.g. when
1971 * moving to a different directory). A fail-safe method to do so would
1972 * be to look up old_dir/old_name, create a link to new_dir/new_name and
1973 * rename the old file using the sillyrename stuff. This way, the original
1974 * file in old_dir will go away when the last process iput()s the inode.
1978 * It actually works quite well. One needs to have the possibility for
1979 * at least one ".nfs..." file in each directory the file ever gets
1980 * moved or linked to which happens automagically with the new
1981 * implementation that only depends on the dcache stuff instead of
1982 * using the inode layer
1984 * Unfortunately, things are a little more complicated than indicated
1985 * above. For a cross-directory move, we want to make sure we can get
1986 * rid of the old inode after the operation. This means there must be
1987 * no pending writes (if it's a file), and the use count must be 1.
1988 * If these conditions are met, we can drop the dentries before doing
1991 int nfs_rename(struct inode
*old_dir
, struct dentry
*old_dentry
,
1992 struct inode
*new_dir
, struct dentry
*new_dentry
)
1994 struct inode
*old_inode
= d_inode(old_dentry
);
1995 struct inode
*new_inode
= d_inode(new_dentry
);
1996 struct dentry
*dentry
= NULL
, *rehash
= NULL
;
1997 struct rpc_task
*task
;
2000 dfprintk(VFS
, "NFS: rename(%pd2 -> %pd2, ct=%d)\n",
2001 old_dentry
, new_dentry
,
2002 d_count(new_dentry
));
2004 trace_nfs_rename_enter(old_dir
, old_dentry
, new_dir
, new_dentry
);
2006 * For non-directories, check whether the target is busy and if so,
2007 * make a copy of the dentry and then do a silly-rename. If the
2008 * silly-rename succeeds, the copied dentry is hashed and becomes
2011 if (new_inode
&& !S_ISDIR(new_inode
->i_mode
)) {
2013 * To prevent any new references to the target during the
2014 * rename, we unhash the dentry in advance.
2016 if (!d_unhashed(new_dentry
)) {
2018 rehash
= new_dentry
;
2021 if (d_count(new_dentry
) > 2) {
2024 /* copy the target dentry's name */
2025 dentry
= d_alloc(new_dentry
->d_parent
,
2026 &new_dentry
->d_name
);
2030 /* silly-rename the existing target ... */
2031 err
= nfs_sillyrename(new_dir
, new_dentry
);
2035 new_dentry
= dentry
;
2041 NFS_PROTO(old_inode
)->return_delegation(old_inode
);
2042 if (new_inode
!= NULL
)
2043 NFS_PROTO(new_inode
)->return_delegation(new_inode
);
2045 task
= nfs_async_rename(old_dir
, new_dir
, old_dentry
, new_dentry
, NULL
);
2047 error
= PTR_ERR(task
);
2051 error
= rpc_wait_for_completion_task(task
);
2053 error
= task
->tk_status
;
2055 nfs_mark_for_revalidate(old_inode
);
2059 trace_nfs_rename_exit(old_dir
, old_dentry
,
2060 new_dir
, new_dentry
, error
);
2062 if (new_inode
!= NULL
)
2063 nfs_drop_nlink(new_inode
);
2064 d_move(old_dentry
, new_dentry
);
2065 nfs_set_verifier(new_dentry
,
2066 nfs_save_change_attribute(new_dir
));
2067 } else if (error
== -ENOENT
)
2068 nfs_dentry_handle_enoent(old_dentry
);
2070 /* new dentry created? */
2075 EXPORT_SYMBOL_GPL(nfs_rename
);
2077 static DEFINE_SPINLOCK(nfs_access_lru_lock
);
2078 static LIST_HEAD(nfs_access_lru_list
);
2079 static atomic_long_t nfs_access_nr_entries
;
2081 static unsigned long nfs_access_max_cachesize
= ULONG_MAX
;
2082 module_param(nfs_access_max_cachesize
, ulong
, 0644);
2083 MODULE_PARM_DESC(nfs_access_max_cachesize
, "NFS access maximum total cache length");
2085 static void nfs_access_free_entry(struct nfs_access_entry
*entry
)
2087 put_rpccred(entry
->cred
);
2088 kfree_rcu(entry
, rcu_head
);
2089 smp_mb__before_atomic();
2090 atomic_long_dec(&nfs_access_nr_entries
);
2091 smp_mb__after_atomic();
2094 static void nfs_access_free_list(struct list_head
*head
)
2096 struct nfs_access_entry
*cache
;
2098 while (!list_empty(head
)) {
2099 cache
= list_entry(head
->next
, struct nfs_access_entry
, lru
);
2100 list_del(&cache
->lru
);
2101 nfs_access_free_entry(cache
);
2105 static unsigned long
2106 nfs_do_access_cache_scan(unsigned int nr_to_scan
)
2109 struct nfs_inode
*nfsi
, *next
;
2110 struct nfs_access_entry
*cache
;
2113 spin_lock(&nfs_access_lru_lock
);
2114 list_for_each_entry_safe(nfsi
, next
, &nfs_access_lru_list
, access_cache_inode_lru
) {
2115 struct inode
*inode
;
2117 if (nr_to_scan
-- == 0)
2119 inode
= &nfsi
->vfs_inode
;
2120 spin_lock(&inode
->i_lock
);
2121 if (list_empty(&nfsi
->access_cache_entry_lru
))
2122 goto remove_lru_entry
;
2123 cache
= list_entry(nfsi
->access_cache_entry_lru
.next
,
2124 struct nfs_access_entry
, lru
);
2125 list_move(&cache
->lru
, &head
);
2126 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
2128 if (!list_empty(&nfsi
->access_cache_entry_lru
))
2129 list_move_tail(&nfsi
->access_cache_inode_lru
,
2130 &nfs_access_lru_list
);
2133 list_del_init(&nfsi
->access_cache_inode_lru
);
2134 smp_mb__before_atomic();
2135 clear_bit(NFS_INO_ACL_LRU_SET
, &nfsi
->flags
);
2136 smp_mb__after_atomic();
2138 spin_unlock(&inode
->i_lock
);
2140 spin_unlock(&nfs_access_lru_lock
);
2141 nfs_access_free_list(&head
);
2146 nfs_access_cache_scan(struct shrinker
*shrink
, struct shrink_control
*sc
)
2148 int nr_to_scan
= sc
->nr_to_scan
;
2149 gfp_t gfp_mask
= sc
->gfp_mask
;
2151 if ((gfp_mask
& GFP_KERNEL
) != GFP_KERNEL
)
2153 return nfs_do_access_cache_scan(nr_to_scan
);
2158 nfs_access_cache_count(struct shrinker
*shrink
, struct shrink_control
*sc
)
2160 return vfs_pressure_ratio(atomic_long_read(&nfs_access_nr_entries
));
2164 nfs_access_cache_enforce_limit(void)
2166 long nr_entries
= atomic_long_read(&nfs_access_nr_entries
);
2168 unsigned int nr_to_scan
;
2170 if (nr_entries
< 0 || nr_entries
<= nfs_access_max_cachesize
)
2173 diff
= nr_entries
- nfs_access_max_cachesize
;
2174 if (diff
< nr_to_scan
)
2176 nfs_do_access_cache_scan(nr_to_scan
);
2179 static void __nfs_access_zap_cache(struct nfs_inode
*nfsi
, struct list_head
*head
)
2181 struct rb_root
*root_node
= &nfsi
->access_cache
;
2183 struct nfs_access_entry
*entry
;
2185 /* Unhook entries from the cache */
2186 while ((n
= rb_first(root_node
)) != NULL
) {
2187 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
2188 rb_erase(n
, root_node
);
2189 list_move(&entry
->lru
, head
);
2191 nfsi
->cache_validity
&= ~NFS_INO_INVALID_ACCESS
;
2194 void nfs_access_zap_cache(struct inode
*inode
)
2198 if (test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
) == 0)
2200 /* Remove from global LRU init */
2201 spin_lock(&nfs_access_lru_lock
);
2202 if (test_and_clear_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
2203 list_del_init(&NFS_I(inode
)->access_cache_inode_lru
);
2205 spin_lock(&inode
->i_lock
);
2206 __nfs_access_zap_cache(NFS_I(inode
), &head
);
2207 spin_unlock(&inode
->i_lock
);
2208 spin_unlock(&nfs_access_lru_lock
);
2209 nfs_access_free_list(&head
);
2211 EXPORT_SYMBOL_GPL(nfs_access_zap_cache
);
2213 static struct nfs_access_entry
*nfs_access_search_rbtree(struct inode
*inode
, struct rpc_cred
*cred
)
2215 struct rb_node
*n
= NFS_I(inode
)->access_cache
.rb_node
;
2216 struct nfs_access_entry
*entry
;
2219 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
2221 if (cred
< entry
->cred
)
2223 else if (cred
> entry
->cred
)
2231 static int nfs_access_get_cached(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_access_entry
*res
)
2233 struct nfs_inode
*nfsi
= NFS_I(inode
);
2234 struct nfs_access_entry
*cache
;
2237 spin_lock(&inode
->i_lock
);
2238 if (nfsi
->cache_validity
& NFS_INO_INVALID_ACCESS
)
2240 cache
= nfs_access_search_rbtree(inode
, cred
);
2243 if (!nfs_have_delegated_attributes(inode
) &&
2244 !time_in_range_open(jiffies
, cache
->jiffies
, cache
->jiffies
+ nfsi
->attrtimeo
))
2246 res
->jiffies
= cache
->jiffies
;
2247 res
->cred
= cache
->cred
;
2248 res
->mask
= cache
->mask
;
2249 list_move_tail(&cache
->lru
, &nfsi
->access_cache_entry_lru
);
2252 spin_unlock(&inode
->i_lock
);
2255 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
2256 list_del(&cache
->lru
);
2257 spin_unlock(&inode
->i_lock
);
2258 nfs_access_free_entry(cache
);
2261 spin_unlock(&inode
->i_lock
);
2262 nfs_access_zap_cache(inode
);
2266 static int nfs_access_get_cached_rcu(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_access_entry
*res
)
2268 /* Only check the most recently returned cache entry,
2269 * but do it without locking.
2271 struct nfs_inode
*nfsi
= NFS_I(inode
);
2272 struct nfs_access_entry
*cache
;
2274 struct list_head
*lh
;
2277 if (nfsi
->cache_validity
& NFS_INO_INVALID_ACCESS
)
2279 lh
= rcu_dereference(nfsi
->access_cache_entry_lru
.prev
);
2280 cache
= list_entry(lh
, struct nfs_access_entry
, lru
);
2281 if (lh
== &nfsi
->access_cache_entry_lru
||
2282 cred
!= cache
->cred
)
2286 if (!nfs_have_delegated_attributes(inode
) &&
2287 !time_in_range_open(jiffies
, cache
->jiffies
, cache
->jiffies
+ nfsi
->attrtimeo
))
2289 res
->jiffies
= cache
->jiffies
;
2290 res
->cred
= cache
->cred
;
2291 res
->mask
= cache
->mask
;
2298 static void nfs_access_add_rbtree(struct inode
*inode
, struct nfs_access_entry
*set
)
2300 struct nfs_inode
*nfsi
= NFS_I(inode
);
2301 struct rb_root
*root_node
= &nfsi
->access_cache
;
2302 struct rb_node
**p
= &root_node
->rb_node
;
2303 struct rb_node
*parent
= NULL
;
2304 struct nfs_access_entry
*entry
;
2306 spin_lock(&inode
->i_lock
);
2307 while (*p
!= NULL
) {
2309 entry
= rb_entry(parent
, struct nfs_access_entry
, rb_node
);
2311 if (set
->cred
< entry
->cred
)
2312 p
= &parent
->rb_left
;
2313 else if (set
->cred
> entry
->cred
)
2314 p
= &parent
->rb_right
;
2318 rb_link_node(&set
->rb_node
, parent
, p
);
2319 rb_insert_color(&set
->rb_node
, root_node
);
2320 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2321 spin_unlock(&inode
->i_lock
);
2324 rb_replace_node(parent
, &set
->rb_node
, root_node
);
2325 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2326 list_del(&entry
->lru
);
2327 spin_unlock(&inode
->i_lock
);
2328 nfs_access_free_entry(entry
);
2331 void nfs_access_add_cache(struct inode
*inode
, struct nfs_access_entry
*set
)
2333 struct nfs_access_entry
*cache
= kmalloc(sizeof(*cache
), GFP_KERNEL
);
2336 RB_CLEAR_NODE(&cache
->rb_node
);
2337 cache
->jiffies
= set
->jiffies
;
2338 cache
->cred
= get_rpccred(set
->cred
);
2339 cache
->mask
= set
->mask
;
2341 /* The above field assignments must be visible
2342 * before this item appears on the lru. We cannot easily
2343 * use rcu_assign_pointer, so just force the memory barrier.
2346 nfs_access_add_rbtree(inode
, cache
);
2348 /* Update accounting */
2349 smp_mb__before_atomic();
2350 atomic_long_inc(&nfs_access_nr_entries
);
2351 smp_mb__after_atomic();
2353 /* Add inode to global LRU list */
2354 if (!test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
)) {
2355 spin_lock(&nfs_access_lru_lock
);
2356 if (!test_and_set_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
2357 list_add_tail(&NFS_I(inode
)->access_cache_inode_lru
,
2358 &nfs_access_lru_list
);
2359 spin_unlock(&nfs_access_lru_lock
);
2361 nfs_access_cache_enforce_limit();
2363 EXPORT_SYMBOL_GPL(nfs_access_add_cache
);
2365 void nfs_access_set_mask(struct nfs_access_entry
*entry
, u32 access_result
)
2368 if (access_result
& NFS4_ACCESS_READ
)
2369 entry
->mask
|= MAY_READ
;
2371 (NFS4_ACCESS_MODIFY
| NFS4_ACCESS_EXTEND
| NFS4_ACCESS_DELETE
))
2372 entry
->mask
|= MAY_WRITE
;
2373 if (access_result
& (NFS4_ACCESS_LOOKUP
|NFS4_ACCESS_EXECUTE
))
2374 entry
->mask
|= MAY_EXEC
;
2376 EXPORT_SYMBOL_GPL(nfs_access_set_mask
);
2378 static int nfs_do_access(struct inode
*inode
, struct rpc_cred
*cred
, int mask
)
2380 struct nfs_access_entry cache
;
2383 trace_nfs_access_enter(inode
);
2385 status
= nfs_access_get_cached_rcu(inode
, cred
, &cache
);
2387 status
= nfs_access_get_cached(inode
, cred
, &cache
);
2392 if (mask
& MAY_NOT_BLOCK
)
2395 /* Be clever: ask server to check for all possible rights */
2396 cache
.mask
= MAY_EXEC
| MAY_WRITE
| MAY_READ
;
2398 cache
.jiffies
= jiffies
;
2399 status
= NFS_PROTO(inode
)->access(inode
, &cache
);
2401 if (status
== -ESTALE
) {
2402 nfs_zap_caches(inode
);
2403 if (!S_ISDIR(inode
->i_mode
))
2404 set_bit(NFS_INO_STALE
, &NFS_I(inode
)->flags
);
2408 nfs_access_add_cache(inode
, &cache
);
2410 if ((mask
& ~cache
.mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) != 0)
2413 trace_nfs_access_exit(inode
, status
);
2417 static int nfs_open_permission_mask(int openflags
)
2421 if (openflags
& __FMODE_EXEC
) {
2422 /* ONLY check exec rights */
2425 if ((openflags
& O_ACCMODE
) != O_WRONLY
)
2427 if ((openflags
& O_ACCMODE
) != O_RDONLY
)
2434 int nfs_may_open(struct inode
*inode
, struct rpc_cred
*cred
, int openflags
)
2436 return nfs_do_access(inode
, cred
, nfs_open_permission_mask(openflags
));
2438 EXPORT_SYMBOL_GPL(nfs_may_open
);
2440 static int nfs_execute_ok(struct inode
*inode
, int mask
)
2442 struct nfs_server
*server
= NFS_SERVER(inode
);
2445 if (mask
& MAY_NOT_BLOCK
)
2446 ret
= nfs_revalidate_inode_rcu(server
, inode
);
2448 ret
= nfs_revalidate_inode(server
, inode
);
2449 if (ret
== 0 && !execute_ok(inode
))
2454 int nfs_permission(struct inode
*inode
, int mask
)
2456 struct rpc_cred
*cred
;
2459 nfs_inc_stats(inode
, NFSIOS_VFSACCESS
);
2461 if ((mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) == 0)
2463 /* Is this sys_access() ? */
2464 if (mask
& (MAY_ACCESS
| MAY_CHDIR
))
2467 switch (inode
->i_mode
& S_IFMT
) {
2471 if ((mask
& MAY_OPEN
) &&
2472 nfs_server_capable(inode
, NFS_CAP_ATOMIC_OPEN
))
2477 * Optimize away all write operations, since the server
2478 * will check permissions when we perform the op.
2480 if ((mask
& MAY_WRITE
) && !(mask
& MAY_READ
))
2485 if (!NFS_PROTO(inode
)->access
)
2488 /* Always try fast lookups first */
2490 cred
= rpc_lookup_cred_nonblock();
2492 res
= nfs_do_access(inode
, cred
, mask
|MAY_NOT_BLOCK
);
2494 res
= PTR_ERR(cred
);
2496 if (res
== -ECHILD
&& !(mask
& MAY_NOT_BLOCK
)) {
2497 /* Fast lookup failed, try the slow way */
2498 cred
= rpc_lookup_cred();
2499 if (!IS_ERR(cred
)) {
2500 res
= nfs_do_access(inode
, cred
, mask
);
2503 res
= PTR_ERR(cred
);
2506 if (!res
&& (mask
& MAY_EXEC
))
2507 res
= nfs_execute_ok(inode
, mask
);
2509 dfprintk(VFS
, "NFS: permission(%s/%lu), mask=0x%x, res=%d\n",
2510 inode
->i_sb
->s_id
, inode
->i_ino
, mask
, res
);
2513 if (mask
& MAY_NOT_BLOCK
)
2516 res
= nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
2518 res
= generic_permission(inode
, mask
);
2521 EXPORT_SYMBOL_GPL(nfs_permission
);
2525 * version-control: t
2526 * kept-new-versions: 5