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
*, int);
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 * The caller is responsible for calling nfs_readdir_release_array(page)
176 struct nfs_cache_array
*nfs_readdir_get_array(struct page
*page
)
180 return ERR_PTR(-EIO
);
183 return ERR_PTR(-ENOMEM
);
188 void nfs_readdir_release_array(struct page
*page
)
194 * we are freeing strings created by nfs_add_to_readdir_array()
197 void nfs_readdir_clear_array(struct page
*page
)
199 struct nfs_cache_array
*array
;
202 array
= kmap_atomic(page
);
203 for (i
= 0; i
< array
->size
; i
++)
204 kfree(array
->array
[i
].string
.name
);
205 kunmap_atomic(array
);
209 * the caller is responsible for freeing qstr.name
210 * when called by nfs_readdir_add_to_array, the strings will be freed in
211 * nfs_clear_readdir_array()
214 int nfs_readdir_make_qstr(struct qstr
*string
, const char *name
, unsigned int len
)
217 string
->name
= kmemdup(name
, len
, GFP_KERNEL
);
218 if (string
->name
== NULL
)
221 * Avoid a kmemleak false positive. The pointer to the name is stored
222 * in a page cache page which kmemleak does not scan.
224 kmemleak_not_leak(string
->name
);
225 string
->hash
= full_name_hash(name
, len
);
230 int nfs_readdir_add_to_array(struct nfs_entry
*entry
, struct page
*page
)
232 struct nfs_cache_array
*array
= nfs_readdir_get_array(page
);
233 struct nfs_cache_array_entry
*cache_entry
;
237 return PTR_ERR(array
);
239 cache_entry
= &array
->array
[array
->size
];
241 /* Check that this entry lies within the page bounds */
243 if ((char *)&cache_entry
[1] - (char *)page_address(page
) > PAGE_SIZE
)
246 cache_entry
->cookie
= entry
->prev_cookie
;
247 cache_entry
->ino
= entry
->ino
;
248 cache_entry
->d_type
= entry
->d_type
;
249 ret
= nfs_readdir_make_qstr(&cache_entry
->string
, entry
->name
, entry
->len
);
252 array
->last_cookie
= entry
->cookie
;
255 array
->eof_index
= array
->size
;
257 nfs_readdir_release_array(page
);
262 int nfs_readdir_search_for_pos(struct nfs_cache_array
*array
, nfs_readdir_descriptor_t
*desc
)
264 loff_t diff
= desc
->ctx
->pos
- desc
->current_index
;
269 if (diff
>= array
->size
) {
270 if (array
->eof_index
>= 0)
275 index
= (unsigned int)diff
;
276 *desc
->dir_cookie
= array
->array
[index
].cookie
;
277 desc
->cache_entry_index
= index
;
285 nfs_readdir_inode_mapping_valid(struct nfs_inode
*nfsi
)
287 if (nfsi
->cache_validity
& (NFS_INO_INVALID_ATTR
|NFS_INO_INVALID_DATA
))
290 return !test_bit(NFS_INO_INVALIDATING
, &nfsi
->flags
);
294 int nfs_readdir_search_for_cookie(struct nfs_cache_array
*array
, nfs_readdir_descriptor_t
*desc
)
298 int status
= -EAGAIN
;
300 for (i
= 0; i
< array
->size
; i
++) {
301 if (array
->array
[i
].cookie
== *desc
->dir_cookie
) {
302 struct nfs_inode
*nfsi
= NFS_I(file_inode(desc
->file
));
303 struct nfs_open_dir_context
*ctx
= desc
->file
->private_data
;
305 new_pos
= desc
->current_index
+ i
;
306 if (ctx
->attr_gencount
!= nfsi
->attr_gencount
||
307 !nfs_readdir_inode_mapping_valid(nfsi
)) {
309 ctx
->attr_gencount
= nfsi
->attr_gencount
;
310 } else if (new_pos
< desc
->ctx
->pos
) {
312 && ctx
->dup_cookie
== *desc
->dir_cookie
) {
313 if (printk_ratelimit()) {
314 pr_notice("NFS: directory %pD2 contains a readdir loop."
315 "Please contact your server vendor. "
316 "The file: %.*s has duplicate cookie %llu\n",
317 desc
->file
, array
->array
[i
].string
.len
,
318 array
->array
[i
].string
.name
, *desc
->dir_cookie
);
323 ctx
->dup_cookie
= *desc
->dir_cookie
;
326 desc
->ctx
->pos
= new_pos
;
327 desc
->cache_entry_index
= i
;
331 if (array
->eof_index
>= 0) {
332 status
= -EBADCOOKIE
;
333 if (*desc
->dir_cookie
== array
->last_cookie
)
341 int nfs_readdir_search_array(nfs_readdir_descriptor_t
*desc
)
343 struct nfs_cache_array
*array
;
346 array
= nfs_readdir_get_array(desc
->page
);
348 status
= PTR_ERR(array
);
352 if (*desc
->dir_cookie
== 0)
353 status
= nfs_readdir_search_for_pos(array
, desc
);
355 status
= nfs_readdir_search_for_cookie(array
, desc
);
357 if (status
== -EAGAIN
) {
358 desc
->last_cookie
= array
->last_cookie
;
359 desc
->current_index
+= array
->size
;
362 nfs_readdir_release_array(desc
->page
);
367 /* Fill a page with xdr information before transferring to the cache page */
369 int nfs_readdir_xdr_filler(struct page
**pages
, nfs_readdir_descriptor_t
*desc
,
370 struct nfs_entry
*entry
, struct file
*file
, struct inode
*inode
)
372 struct nfs_open_dir_context
*ctx
= file
->private_data
;
373 struct rpc_cred
*cred
= ctx
->cred
;
374 unsigned long timestamp
, gencount
;
379 gencount
= nfs_inc_attr_generation_counter();
380 error
= NFS_PROTO(inode
)->readdir(file
->f_path
.dentry
, cred
, entry
->cookie
, pages
,
381 NFS_SERVER(inode
)->dtsize
, desc
->plus
);
383 /* We requested READDIRPLUS, but the server doesn't grok it */
384 if (error
== -ENOTSUPP
&& desc
->plus
) {
385 NFS_SERVER(inode
)->caps
&= ~NFS_CAP_READDIRPLUS
;
386 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
392 desc
->timestamp
= timestamp
;
393 desc
->gencount
= gencount
;
398 static int xdr_decode(nfs_readdir_descriptor_t
*desc
,
399 struct nfs_entry
*entry
, struct xdr_stream
*xdr
)
403 error
= desc
->decode(xdr
, entry
, desc
->plus
);
406 entry
->fattr
->time_start
= desc
->timestamp
;
407 entry
->fattr
->gencount
= desc
->gencount
;
412 int nfs_same_file(struct dentry
*dentry
, struct nfs_entry
*entry
)
414 if (dentry
->d_inode
== NULL
)
416 if (nfs_compare_fh(entry
->fh
, NFS_FH(dentry
->d_inode
)) != 0)
424 bool nfs_use_readdirplus(struct inode
*dir
, struct dir_context
*ctx
)
426 if (!nfs_server_capable(dir
, NFS_CAP_READDIRPLUS
))
428 if (test_and_clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(dir
)->flags
))
436 * This function is called by the lookup code to request the use of
437 * readdirplus to accelerate any future lookups in the same
441 void nfs_advise_use_readdirplus(struct inode
*dir
)
443 set_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(dir
)->flags
);
447 * This function is mainly for use by nfs_getattr().
449 * If this is an 'ls -l', we want to force use of readdirplus.
450 * Do this by checking if there is an active file descriptor
451 * and calling nfs_advise_use_readdirplus, then forcing a
454 void nfs_force_use_readdirplus(struct inode
*dir
)
456 if (!list_empty(&NFS_I(dir
)->open_files
)) {
457 nfs_advise_use_readdirplus(dir
);
458 nfs_zap_mapping(dir
, dir
->i_mapping
);
463 void nfs_prime_dcache(struct dentry
*parent
, struct nfs_entry
*entry
)
465 struct qstr filename
= QSTR_INIT(entry
->name
, entry
->len
);
466 struct dentry
*dentry
;
467 struct dentry
*alias
;
468 struct inode
*dir
= parent
->d_inode
;
472 if (filename
.name
[0] == '.') {
473 if (filename
.len
== 1)
475 if (filename
.len
== 2 && filename
.name
[1] == '.')
478 filename
.hash
= full_name_hash(filename
.name
, filename
.len
);
480 dentry
= d_lookup(parent
, &filename
);
481 if (dentry
!= NULL
) {
482 if (nfs_same_file(dentry
, entry
)) {
483 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
484 status
= nfs_refresh_inode(dentry
->d_inode
, entry
->fattr
);
486 nfs_setsecurity(dentry
->d_inode
, entry
->fattr
, entry
->label
);
489 d_invalidate(dentry
);
494 dentry
= d_alloc(parent
, &filename
);
498 inode
= nfs_fhget(dentry
->d_sb
, entry
->fh
, entry
->fattr
, entry
->label
);
502 alias
= d_splice_alias(inode
, dentry
);
506 nfs_set_verifier(alias
, nfs_save_change_attribute(dir
));
509 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
515 /* Perform conversion from xdr to cache array */
517 int nfs_readdir_page_filler(nfs_readdir_descriptor_t
*desc
, struct nfs_entry
*entry
,
518 struct page
**xdr_pages
, struct page
*page
, unsigned int buflen
)
520 struct xdr_stream stream
;
522 struct page
*scratch
;
523 struct nfs_cache_array
*array
;
524 unsigned int count
= 0;
527 scratch
= alloc_page(GFP_KERNEL
);
531 xdr_init_decode_pages(&stream
, &buf
, xdr_pages
, buflen
);
532 xdr_set_scratch_buffer(&stream
, page_address(scratch
), PAGE_SIZE
);
535 status
= xdr_decode(desc
, entry
, &stream
);
537 if (status
== -EAGAIN
)
545 nfs_prime_dcache(desc
->file
->f_path
.dentry
, entry
);
547 status
= nfs_readdir_add_to_array(entry
, page
);
550 } while (!entry
->eof
);
552 if (count
== 0 || (status
== -EBADCOOKIE
&& entry
->eof
!= 0)) {
553 array
= nfs_readdir_get_array(page
);
554 if (!IS_ERR(array
)) {
555 array
->eof_index
= array
->size
;
557 nfs_readdir_release_array(page
);
559 status
= PTR_ERR(array
);
567 void nfs_readdir_free_pagearray(struct page
**pages
, unsigned int npages
)
570 for (i
= 0; i
< npages
; i
++)
575 void nfs_readdir_free_large_page(void *ptr
, struct page
**pages
,
578 nfs_readdir_free_pagearray(pages
, npages
);
582 * nfs_readdir_large_page will allocate pages that must be freed with a call
583 * to nfs_readdir_free_large_page
586 int nfs_readdir_large_page(struct page
**pages
, unsigned int npages
)
590 for (i
= 0; i
< npages
; i
++) {
591 struct page
*page
= alloc_page(GFP_KERNEL
);
599 nfs_readdir_free_pagearray(pages
, i
);
604 int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t
*desc
, struct page
*page
, struct inode
*inode
)
606 struct page
*pages
[NFS_MAX_READDIR_PAGES
];
607 void *pages_ptr
= NULL
;
608 struct nfs_entry entry
;
609 struct file
*file
= desc
->file
;
610 struct nfs_cache_array
*array
;
611 int status
= -ENOMEM
;
612 unsigned int array_size
= ARRAY_SIZE(pages
);
614 entry
.prev_cookie
= 0;
615 entry
.cookie
= desc
->last_cookie
;
617 entry
.fh
= nfs_alloc_fhandle();
618 entry
.fattr
= nfs_alloc_fattr();
619 entry
.server
= NFS_SERVER(inode
);
620 if (entry
.fh
== NULL
|| entry
.fattr
== NULL
)
623 entry
.label
= nfs4_label_alloc(NFS_SERVER(inode
), GFP_NOWAIT
);
624 if (IS_ERR(entry
.label
)) {
625 status
= PTR_ERR(entry
.label
);
629 array
= nfs_readdir_get_array(page
);
631 status
= PTR_ERR(array
);
634 memset(array
, 0, sizeof(struct nfs_cache_array
));
635 array
->eof_index
= -1;
637 status
= nfs_readdir_large_page(pages
, array_size
);
639 goto out_release_array
;
642 status
= nfs_readdir_xdr_filler(pages
, desc
, &entry
, file
, inode
);
647 status
= nfs_readdir_page_filler(desc
, &entry
, pages
, page
, pglen
);
649 if (status
== -ENOSPC
)
653 } while (array
->eof_index
< 0);
655 nfs_readdir_free_large_page(pages_ptr
, pages
, array_size
);
657 nfs_readdir_release_array(page
);
659 nfs4_label_free(entry
.label
);
661 nfs_free_fattr(entry
.fattr
);
662 nfs_free_fhandle(entry
.fh
);
667 * Now we cache directories properly, by converting xdr information
668 * to an array that can be used for lookups later. This results in
669 * fewer cache pages, since we can store more information on each page.
670 * We only need to convert from xdr once so future lookups are much simpler
673 int nfs_readdir_filler(nfs_readdir_descriptor_t
*desc
, struct page
* page
)
675 struct inode
*inode
= file_inode(desc
->file
);
678 ret
= nfs_readdir_xdr_to_array(desc
, page
, inode
);
681 SetPageUptodate(page
);
683 if (invalidate_inode_pages2_range(inode
->i_mapping
, page
->index
+ 1, -1) < 0) {
684 /* Should never happen */
685 nfs_zap_mapping(inode
, inode
->i_mapping
);
695 void cache_page_release(nfs_readdir_descriptor_t
*desc
)
697 if (!desc
->page
->mapping
)
698 nfs_readdir_clear_array(desc
->page
);
699 page_cache_release(desc
->page
);
704 struct page
*get_cache_page(nfs_readdir_descriptor_t
*desc
)
706 return read_cache_page(file_inode(desc
->file
)->i_mapping
,
707 desc
->page_index
, (filler_t
*)nfs_readdir_filler
, desc
);
711 * Returns 0 if desc->dir_cookie was found on page desc->page_index
714 int find_cache_page(nfs_readdir_descriptor_t
*desc
)
718 desc
->page
= get_cache_page(desc
);
719 if (IS_ERR(desc
->page
))
720 return PTR_ERR(desc
->page
);
722 res
= nfs_readdir_search_array(desc
);
724 cache_page_release(desc
);
728 /* Search for desc->dir_cookie from the beginning of the page cache */
730 int readdir_search_pagecache(nfs_readdir_descriptor_t
*desc
)
734 if (desc
->page_index
== 0) {
735 desc
->current_index
= 0;
736 desc
->last_cookie
= 0;
739 res
= find_cache_page(desc
);
740 } while (res
== -EAGAIN
);
745 * Once we've found the start of the dirent within a page: fill 'er up...
748 int nfs_do_filldir(nfs_readdir_descriptor_t
*desc
)
750 struct file
*file
= desc
->file
;
753 struct nfs_cache_array
*array
= NULL
;
754 struct nfs_open_dir_context
*ctx
= file
->private_data
;
756 array
= nfs_readdir_get_array(desc
->page
);
758 res
= PTR_ERR(array
);
762 for (i
= desc
->cache_entry_index
; i
< array
->size
; i
++) {
763 struct nfs_cache_array_entry
*ent
;
765 ent
= &array
->array
[i
];
766 if (!dir_emit(desc
->ctx
, ent
->string
.name
, ent
->string
.len
,
767 nfs_compat_user_ino64(ent
->ino
), ent
->d_type
)) {
772 if (i
< (array
->size
-1))
773 *desc
->dir_cookie
= array
->array
[i
+1].cookie
;
775 *desc
->dir_cookie
= array
->last_cookie
;
779 if (array
->eof_index
>= 0)
782 nfs_readdir_release_array(desc
->page
);
784 cache_page_release(desc
);
785 dfprintk(DIRCACHE
, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n",
786 (unsigned long long)*desc
->dir_cookie
, res
);
791 * If we cannot find a cookie in our cache, we suspect that this is
792 * because it points to a deleted file, so we ask the server to return
793 * whatever it thinks is the next entry. We then feed this to filldir.
794 * If all goes well, we should then be able to find our way round the
795 * cache on the next call to readdir_search_pagecache();
797 * NOTE: we cannot add the anonymous page to the pagecache because
798 * the data it contains might not be page aligned. Besides,
799 * we should already have a complete representation of the
800 * directory in the page cache by the time we get here.
803 int uncached_readdir(nfs_readdir_descriptor_t
*desc
)
805 struct page
*page
= NULL
;
807 struct inode
*inode
= file_inode(desc
->file
);
808 struct nfs_open_dir_context
*ctx
= desc
->file
->private_data
;
810 dfprintk(DIRCACHE
, "NFS: uncached_readdir() searching for cookie %Lu\n",
811 (unsigned long long)*desc
->dir_cookie
);
813 page
= alloc_page(GFP_HIGHUSER
);
819 desc
->page_index
= 0;
820 desc
->last_cookie
= *desc
->dir_cookie
;
824 status
= nfs_readdir_xdr_to_array(desc
, page
, inode
);
828 status
= nfs_do_filldir(desc
);
831 dfprintk(DIRCACHE
, "NFS: %s: returns %d\n",
835 cache_page_release(desc
);
839 static bool nfs_dir_mapping_need_revalidate(struct inode
*dir
)
841 struct nfs_inode
*nfsi
= NFS_I(dir
);
843 if (nfs_attribute_cache_expired(dir
))
845 if (nfsi
->cache_validity
& NFS_INO_INVALID_DATA
)
850 /* The file offset position represents the dirent entry number. A
851 last cookie cache takes care of the common case of reading the
854 static int nfs_readdir(struct file
*file
, struct dir_context
*ctx
)
856 struct dentry
*dentry
= file
->f_path
.dentry
;
857 struct inode
*inode
= dentry
->d_inode
;
858 nfs_readdir_descriptor_t my_desc
,
860 struct nfs_open_dir_context
*dir_ctx
= file
->private_data
;
863 dfprintk(FILE, "NFS: readdir(%pD2) starting at cookie %llu\n",
864 file
, (long long)ctx
->pos
);
865 nfs_inc_stats(inode
, NFSIOS_VFSGETDENTS
);
868 * ctx->pos points to the dirent entry number.
869 * *desc->dir_cookie has the cookie for the next entry. We have
870 * to either find the entry with the appropriate number or
871 * revalidate the cookie.
873 memset(desc
, 0, sizeof(*desc
));
877 desc
->dir_cookie
= &dir_ctx
->dir_cookie
;
878 desc
->decode
= NFS_PROTO(inode
)->decode_dirent
;
879 desc
->plus
= nfs_use_readdirplus(inode
, ctx
) ? 1 : 0;
881 nfs_block_sillyrename(dentry
);
882 if (ctx
->pos
== 0 || nfs_dir_mapping_need_revalidate(inode
))
883 res
= nfs_revalidate_mapping(inode
, file
->f_mapping
);
888 res
= readdir_search_pagecache(desc
);
890 if (res
== -EBADCOOKIE
) {
892 /* This means either end of directory */
893 if (*desc
->dir_cookie
&& desc
->eof
== 0) {
894 /* Or that the server has 'lost' a cookie */
895 res
= uncached_readdir(desc
);
901 if (res
== -ETOOSMALL
&& desc
->plus
) {
902 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
903 nfs_zap_caches(inode
);
904 desc
->page_index
= 0;
912 res
= nfs_do_filldir(desc
);
915 } while (!desc
->eof
);
917 nfs_unblock_sillyrename(dentry
);
920 dfprintk(FILE, "NFS: readdir(%pD2) returns %d\n", file
, res
);
924 static loff_t
nfs_llseek_dir(struct file
*filp
, loff_t offset
, int whence
)
926 struct inode
*inode
= file_inode(filp
);
927 struct nfs_open_dir_context
*dir_ctx
= filp
->private_data
;
929 dfprintk(FILE, "NFS: llseek dir(%pD2, %lld, %d)\n",
930 filp
, offset
, whence
);
932 mutex_lock(&inode
->i_mutex
);
935 offset
+= filp
->f_pos
;
943 if (offset
!= filp
->f_pos
) {
944 filp
->f_pos
= offset
;
945 dir_ctx
->dir_cookie
= 0;
949 mutex_unlock(&inode
->i_mutex
);
954 * All directory operations under NFS are synchronous, so fsync()
955 * is a dummy operation.
957 static int nfs_fsync_dir(struct file
*filp
, loff_t start
, loff_t end
,
960 struct inode
*inode
= file_inode(filp
);
962 dfprintk(FILE, "NFS: fsync dir(%pD2) datasync %d\n", filp
, datasync
);
964 mutex_lock(&inode
->i_mutex
);
965 nfs_inc_stats(inode
, NFSIOS_VFSFSYNC
);
966 mutex_unlock(&inode
->i_mutex
);
971 * nfs_force_lookup_revalidate - Mark the directory as having changed
972 * @dir - pointer to directory inode
974 * This forces the revalidation code in nfs_lookup_revalidate() to do a
975 * full lookup on all child dentries of 'dir' whenever a change occurs
976 * on the server that might have invalidated our dcache.
978 * The caller should be holding dir->i_lock
980 void nfs_force_lookup_revalidate(struct inode
*dir
)
982 NFS_I(dir
)->cache_change_attribute
++;
984 EXPORT_SYMBOL_GPL(nfs_force_lookup_revalidate
);
987 * A check for whether or not the parent directory has changed.
988 * In the case it has, we assume that the dentries are untrustworthy
989 * and may need to be looked up again.
990 * If rcu_walk prevents us from performing a full check, return 0.
992 static int nfs_check_verifier(struct inode
*dir
, struct dentry
*dentry
,
999 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONE
)
1001 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
1003 /* Revalidate nfsi->cache_change_attribute before we declare a match */
1005 ret
= nfs_revalidate_inode_rcu(NFS_SERVER(dir
), dir
);
1007 ret
= nfs_revalidate_inode(NFS_SERVER(dir
), dir
);
1010 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
1016 * Use intent information to check whether or not we're going to do
1017 * an O_EXCL create using this path component.
1019 static int nfs_is_exclusive_create(struct inode
*dir
, unsigned int flags
)
1021 if (NFS_PROTO(dir
)->version
== 2)
1023 return flags
& LOOKUP_EXCL
;
1027 * Inode and filehandle revalidation for lookups.
1029 * We force revalidation in the cases where the VFS sets LOOKUP_REVAL,
1030 * or if the intent information indicates that we're about to open this
1031 * particular file and the "nocto" mount flag is not set.
1035 int nfs_lookup_verify_inode(struct inode
*inode
, unsigned int flags
)
1037 struct nfs_server
*server
= NFS_SERVER(inode
);
1040 if (IS_AUTOMOUNT(inode
))
1042 /* VFS wants an on-the-wire revalidation */
1043 if (flags
& LOOKUP_REVAL
)
1045 /* This is an open(2) */
1046 if ((flags
& LOOKUP_OPEN
) && !(server
->flags
& NFS_MOUNT_NOCTO
) &&
1047 (S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
)))
1050 return (inode
->i_nlink
== 0) ? -ENOENT
: 0;
1052 if (flags
& LOOKUP_RCU
)
1054 ret
= __nfs_revalidate_inode(server
, inode
);
1061 * We judge how long we want to trust negative
1062 * dentries by looking at the parent inode mtime.
1064 * If parent mtime has changed, we revalidate, else we wait for a
1065 * period corresponding to the parent's attribute cache timeout value.
1067 * If LOOKUP_RCU prevents us from performing a full check, return 1
1068 * suggesting a reval is needed.
1071 int nfs_neg_need_reval(struct inode
*dir
, struct dentry
*dentry
,
1074 /* Don't revalidate a negative dentry if we're creating a new file */
1075 if (flags
& LOOKUP_CREATE
)
1077 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONEG
)
1079 return !nfs_check_verifier(dir
, dentry
, flags
& LOOKUP_RCU
);
1083 * This is called every time the dcache has a lookup hit,
1084 * and we should check whether we can really trust that
1087 * NOTE! The hit can be a negative hit too, don't assume
1090 * If the parent directory is seen to have changed, we throw out the
1091 * cached dentry and do a new lookup.
1093 static int nfs_lookup_revalidate(struct dentry
*dentry
, unsigned int flags
)
1096 struct inode
*inode
;
1097 struct dentry
*parent
;
1098 struct nfs_fh
*fhandle
= NULL
;
1099 struct nfs_fattr
*fattr
= NULL
;
1100 struct nfs4_label
*label
= NULL
;
1103 if (flags
& LOOKUP_RCU
) {
1104 parent
= ACCESS_ONCE(dentry
->d_parent
);
1105 dir
= ACCESS_ONCE(parent
->d_inode
);
1109 parent
= dget_parent(dentry
);
1110 dir
= parent
->d_inode
;
1112 nfs_inc_stats(dir
, NFSIOS_DENTRYREVALIDATE
);
1113 inode
= dentry
->d_inode
;
1116 if (nfs_neg_need_reval(dir
, dentry
, flags
)) {
1117 if (flags
& LOOKUP_RCU
)
1121 goto out_valid_noent
;
1124 if (is_bad_inode(inode
)) {
1125 if (flags
& LOOKUP_RCU
)
1127 dfprintk(LOOKUPCACHE
, "%s: %pd2 has dud inode\n",
1132 if (NFS_PROTO(dir
)->have_delegation(inode
, FMODE_READ
))
1133 goto out_set_verifier
;
1135 /* Force a full look up iff the parent directory has changed */
1136 if (!nfs_is_exclusive_create(dir
, flags
) &&
1137 nfs_check_verifier(dir
, dentry
, flags
& LOOKUP_RCU
)) {
1139 if (nfs_lookup_verify_inode(inode
, flags
)) {
1140 if (flags
& LOOKUP_RCU
)
1142 goto out_zap_parent
;
1147 if (flags
& LOOKUP_RCU
)
1150 if (NFS_STALE(inode
))
1154 fhandle
= nfs_alloc_fhandle();
1155 fattr
= nfs_alloc_fattr();
1156 if (fhandle
== NULL
|| fattr
== NULL
)
1159 label
= nfs4_label_alloc(NFS_SERVER(inode
), GFP_NOWAIT
);
1163 trace_nfs_lookup_revalidate_enter(dir
, dentry
, flags
);
1164 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
, label
);
1165 trace_nfs_lookup_revalidate_exit(dir
, dentry
, flags
, error
);
1168 if (nfs_compare_fh(NFS_FH(inode
), fhandle
))
1170 if ((error
= nfs_refresh_inode(inode
, fattr
)) != 0)
1173 nfs_setsecurity(inode
, fattr
, label
);
1175 nfs_free_fattr(fattr
);
1176 nfs_free_fhandle(fhandle
);
1177 nfs4_label_free(label
);
1180 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1182 /* Success: notify readdir to use READDIRPLUS */
1183 nfs_advise_use_readdirplus(dir
);
1185 if (flags
& LOOKUP_RCU
) {
1186 if (parent
!= ACCESS_ONCE(dentry
->d_parent
))
1190 dfprintk(LOOKUPCACHE
, "NFS: %s(%pd2) is valid\n",
1194 nfs_zap_caches(dir
);
1196 WARN_ON(flags
& LOOKUP_RCU
);
1197 nfs_free_fattr(fattr
);
1198 nfs_free_fhandle(fhandle
);
1199 nfs4_label_free(label
);
1200 nfs_mark_for_revalidate(dir
);
1201 if (inode
&& S_ISDIR(inode
->i_mode
)) {
1202 /* Purge readdir caches. */
1203 nfs_zap_caches(inode
);
1205 * We can't d_drop the root of a disconnected tree:
1206 * its d_hash is on the s_anon list and d_drop() would hide
1207 * it from shrink_dcache_for_unmount(), leading to busy
1208 * inodes on unmount and further oopses.
1210 if (IS_ROOT(dentry
))
1214 dfprintk(LOOKUPCACHE
, "NFS: %s(%pd2) is invalid\n",
1218 WARN_ON(flags
& LOOKUP_RCU
);
1219 nfs_free_fattr(fattr
);
1220 nfs_free_fhandle(fhandle
);
1221 nfs4_label_free(label
);
1223 dfprintk(LOOKUPCACHE
, "NFS: %s(%pd2) lookup returned error %d\n",
1224 __func__
, dentry
, error
);
1229 * A weaker form of d_revalidate for revalidating just the dentry->d_inode
1230 * when we don't really care about the dentry name. This is called when a
1231 * pathwalk ends on a dentry that was not found via a normal lookup in the
1232 * parent dir (e.g.: ".", "..", procfs symlinks or mountpoint traversals).
1234 * In this situation, we just want to verify that the inode itself is OK
1235 * since the dentry might have changed on the server.
1237 static int nfs_weak_revalidate(struct dentry
*dentry
, unsigned int flags
)
1240 struct inode
*inode
= dentry
->d_inode
;
1243 * I believe we can only get a negative dentry here in the case of a
1244 * procfs-style symlink. Just assume it's correct for now, but we may
1245 * eventually need to do something more here.
1248 dfprintk(LOOKUPCACHE
, "%s: %pd2 has negative inode\n",
1253 if (is_bad_inode(inode
)) {
1254 dfprintk(LOOKUPCACHE
, "%s: %pd2 has dud inode\n",
1259 error
= nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
1260 dfprintk(LOOKUPCACHE
, "NFS: %s: inode %lu is %s\n",
1261 __func__
, inode
->i_ino
, error
? "invalid" : "valid");
1266 * This is called from dput() when d_count is going to 0.
1268 static int nfs_dentry_delete(const struct dentry
*dentry
)
1270 dfprintk(VFS
, "NFS: dentry_delete(%pd2, %x)\n",
1271 dentry
, dentry
->d_flags
);
1273 /* Unhash any dentry with a stale inode */
1274 if (dentry
->d_inode
!= NULL
&& NFS_STALE(dentry
->d_inode
))
1277 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1278 /* Unhash it, so that ->d_iput() would be called */
1281 if (!(dentry
->d_sb
->s_flags
& MS_ACTIVE
)) {
1282 /* Unhash it, so that ancestors of killed async unlink
1283 * files will be cleaned up during umount */
1290 /* Ensure that we revalidate inode->i_nlink */
1291 static void nfs_drop_nlink(struct inode
*inode
)
1293 spin_lock(&inode
->i_lock
);
1294 /* drop the inode if we're reasonably sure this is the last link */
1295 if (inode
->i_nlink
== 1)
1297 NFS_I(inode
)->cache_validity
|= NFS_INO_INVALID_ATTR
;
1298 spin_unlock(&inode
->i_lock
);
1302 * Called when the dentry loses inode.
1303 * We use it to clean up silly-renamed files.
1305 static void nfs_dentry_iput(struct dentry
*dentry
, struct inode
*inode
)
1307 if (S_ISDIR(inode
->i_mode
))
1308 /* drop any readdir cache as it could easily be old */
1309 NFS_I(inode
)->cache_validity
|= NFS_INO_INVALID_DATA
;
1311 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1312 nfs_complete_unlink(dentry
, inode
);
1313 nfs_drop_nlink(inode
);
1318 static void nfs_d_release(struct dentry
*dentry
)
1320 /* free cached devname value, if it survived that far */
1321 if (unlikely(dentry
->d_fsdata
)) {
1322 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
)
1325 kfree(dentry
->d_fsdata
);
1329 const struct dentry_operations nfs_dentry_operations
= {
1330 .d_revalidate
= nfs_lookup_revalidate
,
1331 .d_weak_revalidate
= nfs_weak_revalidate
,
1332 .d_delete
= nfs_dentry_delete
,
1333 .d_iput
= nfs_dentry_iput
,
1334 .d_automount
= nfs_d_automount
,
1335 .d_release
= nfs_d_release
,
1337 EXPORT_SYMBOL_GPL(nfs_dentry_operations
);
1339 struct dentry
*nfs_lookup(struct inode
*dir
, struct dentry
* dentry
, unsigned int flags
)
1342 struct dentry
*parent
;
1343 struct inode
*inode
= NULL
;
1344 struct nfs_fh
*fhandle
= NULL
;
1345 struct nfs_fattr
*fattr
= NULL
;
1346 struct nfs4_label
*label
= NULL
;
1349 dfprintk(VFS
, "NFS: lookup(%pd2)\n", dentry
);
1350 nfs_inc_stats(dir
, NFSIOS_VFSLOOKUP
);
1352 res
= ERR_PTR(-ENAMETOOLONG
);
1353 if (dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
)
1357 * If we're doing an exclusive create, optimize away the lookup
1358 * but don't hash the dentry.
1360 if (nfs_is_exclusive_create(dir
, flags
)) {
1361 d_instantiate(dentry
, NULL
);
1366 res
= ERR_PTR(-ENOMEM
);
1367 fhandle
= nfs_alloc_fhandle();
1368 fattr
= nfs_alloc_fattr();
1369 if (fhandle
== NULL
|| fattr
== NULL
)
1372 label
= nfs4_label_alloc(NFS_SERVER(dir
), GFP_NOWAIT
);
1376 parent
= dentry
->d_parent
;
1377 /* Protect against concurrent sillydeletes */
1378 trace_nfs_lookup_enter(dir
, dentry
, flags
);
1379 nfs_block_sillyrename(parent
);
1380 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
, label
);
1381 if (error
== -ENOENT
)
1384 res
= ERR_PTR(error
);
1385 goto out_unblock_sillyrename
;
1387 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
, label
);
1388 res
= ERR_CAST(inode
);
1390 goto out_unblock_sillyrename
;
1392 /* Success: notify readdir to use READDIRPLUS */
1393 nfs_advise_use_readdirplus(dir
);
1396 res
= d_splice_alias(inode
, dentry
);
1399 goto out_unblock_sillyrename
;
1402 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1403 out_unblock_sillyrename
:
1404 nfs_unblock_sillyrename(parent
);
1405 trace_nfs_lookup_exit(dir
, dentry
, flags
, error
);
1406 nfs4_label_free(label
);
1408 nfs_free_fattr(fattr
);
1409 nfs_free_fhandle(fhandle
);
1412 EXPORT_SYMBOL_GPL(nfs_lookup
);
1414 #if IS_ENABLED(CONFIG_NFS_V4)
1415 static int nfs4_lookup_revalidate(struct dentry
*, unsigned int);
1417 const struct dentry_operations nfs4_dentry_operations
= {
1418 .d_revalidate
= nfs4_lookup_revalidate
,
1419 .d_delete
= nfs_dentry_delete
,
1420 .d_iput
= nfs_dentry_iput
,
1421 .d_automount
= nfs_d_automount
,
1422 .d_release
= nfs_d_release
,
1424 EXPORT_SYMBOL_GPL(nfs4_dentry_operations
);
1426 static fmode_t
flags_to_mode(int flags
)
1428 fmode_t res
= (__force fmode_t
)flags
& FMODE_EXEC
;
1429 if ((flags
& O_ACCMODE
) != O_WRONLY
)
1431 if ((flags
& O_ACCMODE
) != O_RDONLY
)
1436 static struct nfs_open_context
*create_nfs_open_context(struct dentry
*dentry
, int open_flags
)
1438 return alloc_nfs_open_context(dentry
, flags_to_mode(open_flags
));
1441 static int do_open(struct inode
*inode
, struct file
*filp
)
1443 nfs_fscache_open_file(inode
, filp
);
1447 static int nfs_finish_open(struct nfs_open_context
*ctx
,
1448 struct dentry
*dentry
,
1449 struct file
*file
, unsigned open_flags
,
1454 if ((open_flags
& (O_CREAT
| O_EXCL
)) == (O_CREAT
| O_EXCL
))
1455 *opened
|= FILE_CREATED
;
1457 err
= finish_open(file
, dentry
, do_open
, opened
);
1460 nfs_file_set_open_context(file
, ctx
);
1466 int nfs_atomic_open(struct inode
*dir
, struct dentry
*dentry
,
1467 struct file
*file
, unsigned open_flags
,
1468 umode_t mode
, int *opened
)
1470 struct nfs_open_context
*ctx
;
1472 struct iattr attr
= { .ia_valid
= ATTR_OPEN
};
1473 struct inode
*inode
;
1474 unsigned int lookup_flags
= 0;
1477 /* Expect a negative dentry */
1478 BUG_ON(dentry
->d_inode
);
1480 dfprintk(VFS
, "NFS: atomic_open(%s/%lu), %pd\n",
1481 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1483 err
= nfs_check_flags(open_flags
);
1487 /* NFS only supports OPEN on regular files */
1488 if ((open_flags
& O_DIRECTORY
)) {
1489 if (!d_unhashed(dentry
)) {
1491 * Hashed negative dentry with O_DIRECTORY: dentry was
1492 * revalidated and is fine, no need to perform lookup
1497 lookup_flags
= LOOKUP_OPEN
|LOOKUP_DIRECTORY
;
1501 if (dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
)
1502 return -ENAMETOOLONG
;
1504 if (open_flags
& O_CREAT
) {
1505 attr
.ia_valid
|= ATTR_MODE
;
1506 attr
.ia_mode
= mode
& ~current_umask();
1508 if (open_flags
& O_TRUNC
) {
1509 attr
.ia_valid
|= ATTR_SIZE
;
1513 ctx
= create_nfs_open_context(dentry
, open_flags
);
1518 trace_nfs_atomic_open_enter(dir
, ctx
, open_flags
);
1519 nfs_block_sillyrename(dentry
->d_parent
);
1520 inode
= NFS_PROTO(dir
)->open_context(dir
, ctx
, open_flags
, &attr
, opened
);
1521 nfs_unblock_sillyrename(dentry
->d_parent
);
1522 if (IS_ERR(inode
)) {
1523 err
= PTR_ERR(inode
);
1524 trace_nfs_atomic_open_exit(dir
, ctx
, open_flags
, err
);
1525 put_nfs_open_context(ctx
);
1529 d_add(dentry
, NULL
);
1530 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1536 if (!(open_flags
& O_NOFOLLOW
))
1546 err
= nfs_finish_open(ctx
, ctx
->dentry
, file
, open_flags
, opened
);
1547 trace_nfs_atomic_open_exit(dir
, ctx
, open_flags
, err
);
1548 put_nfs_open_context(ctx
);
1553 res
= nfs_lookup(dir
, dentry
, lookup_flags
);
1558 return finish_no_open(file
, res
);
1560 EXPORT_SYMBOL_GPL(nfs_atomic_open
);
1562 static int nfs4_lookup_revalidate(struct dentry
*dentry
, unsigned int flags
)
1564 struct inode
*inode
;
1567 if (!(flags
& LOOKUP_OPEN
) || (flags
& LOOKUP_DIRECTORY
))
1569 if (d_mountpoint(dentry
))
1571 if (NFS_SB(dentry
->d_sb
)->caps
& NFS_CAP_ATOMIC_OPEN_V1
)
1574 inode
= dentry
->d_inode
;
1576 /* We can't create new files in nfs_open_revalidate(), so we
1577 * optimize away revalidation of negative dentries.
1579 if (inode
== NULL
) {
1580 struct dentry
*parent
;
1583 if (flags
& LOOKUP_RCU
) {
1584 parent
= ACCESS_ONCE(dentry
->d_parent
);
1585 dir
= ACCESS_ONCE(parent
->d_inode
);
1589 parent
= dget_parent(dentry
);
1590 dir
= parent
->d_inode
;
1592 if (!nfs_neg_need_reval(dir
, dentry
, flags
))
1594 else if (flags
& LOOKUP_RCU
)
1596 if (!(flags
& LOOKUP_RCU
))
1598 else if (parent
!= ACCESS_ONCE(dentry
->d_parent
))
1603 /* NFS only supports OPEN on regular files */
1604 if (!S_ISREG(inode
->i_mode
))
1606 /* We cannot do exclusive creation on a positive dentry */
1607 if (flags
& LOOKUP_EXCL
)
1610 /* Let f_op->open() actually open (and revalidate) the file */
1617 return nfs_lookup_revalidate(dentry
, flags
);
1620 #endif /* CONFIG_NFSV4 */
1623 * Code common to create, mkdir, and mknod.
1625 int nfs_instantiate(struct dentry
*dentry
, struct nfs_fh
*fhandle
,
1626 struct nfs_fattr
*fattr
,
1627 struct nfs4_label
*label
)
1629 struct dentry
*parent
= dget_parent(dentry
);
1630 struct inode
*dir
= parent
->d_inode
;
1631 struct inode
*inode
;
1632 int error
= -EACCES
;
1636 /* We may have been initialized further down */
1637 if (dentry
->d_inode
)
1639 if (fhandle
->size
== 0) {
1640 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
, NULL
);
1644 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1645 if (!(fattr
->valid
& NFS_ATTR_FATTR
)) {
1646 struct nfs_server
*server
= NFS_SB(dentry
->d_sb
);
1647 error
= server
->nfs_client
->rpc_ops
->getattr(server
, fhandle
, fattr
, NULL
);
1651 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
, label
);
1652 error
= PTR_ERR(inode
);
1655 d_add(dentry
, inode
);
1660 nfs_mark_for_revalidate(dir
);
1664 EXPORT_SYMBOL_GPL(nfs_instantiate
);
1667 * Following a failed create operation, we drop the dentry rather
1668 * than retain a negative dentry. This avoids a problem in the event
1669 * that the operation succeeded on the server, but an error in the
1670 * reply path made it appear to have failed.
1672 int nfs_create(struct inode
*dir
, struct dentry
*dentry
,
1673 umode_t mode
, bool excl
)
1676 int open_flags
= excl
? O_CREAT
| O_EXCL
: O_CREAT
;
1679 dfprintk(VFS
, "NFS: create(%s/%lu), %pd\n",
1680 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1682 attr
.ia_mode
= mode
;
1683 attr
.ia_valid
= ATTR_MODE
;
1685 trace_nfs_create_enter(dir
, dentry
, open_flags
);
1686 error
= NFS_PROTO(dir
)->create(dir
, dentry
, &attr
, open_flags
);
1687 trace_nfs_create_exit(dir
, dentry
, open_flags
, error
);
1695 EXPORT_SYMBOL_GPL(nfs_create
);
1698 * See comments for nfs_proc_create regarding failed operations.
1701 nfs_mknod(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
, dev_t rdev
)
1706 dfprintk(VFS
, "NFS: mknod(%s/%lu), %pd\n",
1707 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1709 if (!new_valid_dev(rdev
))
1712 attr
.ia_mode
= mode
;
1713 attr
.ia_valid
= ATTR_MODE
;
1715 trace_nfs_mknod_enter(dir
, dentry
);
1716 status
= NFS_PROTO(dir
)->mknod(dir
, dentry
, &attr
, rdev
);
1717 trace_nfs_mknod_exit(dir
, dentry
, status
);
1725 EXPORT_SYMBOL_GPL(nfs_mknod
);
1728 * See comments for nfs_proc_create regarding failed operations.
1730 int nfs_mkdir(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
)
1735 dfprintk(VFS
, "NFS: mkdir(%s/%lu), %pd\n",
1736 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1738 attr
.ia_valid
= ATTR_MODE
;
1739 attr
.ia_mode
= mode
| S_IFDIR
;
1741 trace_nfs_mkdir_enter(dir
, dentry
);
1742 error
= NFS_PROTO(dir
)->mkdir(dir
, dentry
, &attr
);
1743 trace_nfs_mkdir_exit(dir
, dentry
, error
);
1751 EXPORT_SYMBOL_GPL(nfs_mkdir
);
1753 static void nfs_dentry_handle_enoent(struct dentry
*dentry
)
1755 if (dentry
->d_inode
!= NULL
&& !d_unhashed(dentry
))
1759 int nfs_rmdir(struct inode
*dir
, struct dentry
*dentry
)
1763 dfprintk(VFS
, "NFS: rmdir(%s/%lu), %pd\n",
1764 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1766 trace_nfs_rmdir_enter(dir
, dentry
);
1767 if (dentry
->d_inode
) {
1768 nfs_wait_on_sillyrename(dentry
);
1769 error
= NFS_PROTO(dir
)->rmdir(dir
, &dentry
->d_name
);
1770 /* Ensure the VFS deletes this inode */
1773 clear_nlink(dentry
->d_inode
);
1776 nfs_dentry_handle_enoent(dentry
);
1779 error
= NFS_PROTO(dir
)->rmdir(dir
, &dentry
->d_name
);
1780 trace_nfs_rmdir_exit(dir
, dentry
, error
);
1784 EXPORT_SYMBOL_GPL(nfs_rmdir
);
1787 * Remove a file after making sure there are no pending writes,
1788 * and after checking that the file has only one user.
1790 * We invalidate the attribute cache and free the inode prior to the operation
1791 * to avoid possible races if the server reuses the inode.
1793 static int nfs_safe_remove(struct dentry
*dentry
)
1795 struct inode
*dir
= dentry
->d_parent
->d_inode
;
1796 struct inode
*inode
= dentry
->d_inode
;
1799 dfprintk(VFS
, "NFS: safe_remove(%pd2)\n", dentry
);
1801 /* If the dentry was sillyrenamed, we simply call d_delete() */
1802 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1807 trace_nfs_remove_enter(dir
, dentry
);
1808 if (inode
!= NULL
) {
1809 NFS_PROTO(inode
)->return_delegation(inode
);
1810 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1812 nfs_drop_nlink(inode
);
1814 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1815 if (error
== -ENOENT
)
1816 nfs_dentry_handle_enoent(dentry
);
1817 trace_nfs_remove_exit(dir
, dentry
, error
);
1822 /* We do silly rename. In case sillyrename() returns -EBUSY, the inode
1823 * belongs to an active ".nfs..." file and we return -EBUSY.
1825 * If sillyrename() returns 0, we do nothing, otherwise we unlink.
1827 int nfs_unlink(struct inode
*dir
, struct dentry
*dentry
)
1830 int need_rehash
= 0;
1832 dfprintk(VFS
, "NFS: unlink(%s/%lu, %pd)\n", dir
->i_sb
->s_id
,
1833 dir
->i_ino
, dentry
);
1835 trace_nfs_unlink_enter(dir
, dentry
);
1836 spin_lock(&dentry
->d_lock
);
1837 if (d_count(dentry
) > 1) {
1838 spin_unlock(&dentry
->d_lock
);
1839 /* Start asynchronous writeout of the inode */
1840 write_inode_now(dentry
->d_inode
, 0);
1841 error
= nfs_sillyrename(dir
, dentry
);
1844 if (!d_unhashed(dentry
)) {
1848 spin_unlock(&dentry
->d_lock
);
1849 error
= nfs_safe_remove(dentry
);
1850 if (!error
|| error
== -ENOENT
) {
1851 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1852 } else if (need_rehash
)
1855 trace_nfs_unlink_exit(dir
, dentry
, error
);
1858 EXPORT_SYMBOL_GPL(nfs_unlink
);
1861 * To create a symbolic link, most file systems instantiate a new inode,
1862 * add a page to it containing the path, then write it out to the disk
1863 * using prepare_write/commit_write.
1865 * Unfortunately the NFS client can't create the in-core inode first
1866 * because it needs a file handle to create an in-core inode (see
1867 * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the
1868 * symlink request has completed on the server.
1870 * So instead we allocate a raw page, copy the symname into it, then do
1871 * the SYMLINK request with the page as the buffer. If it succeeds, we
1872 * now have a new file handle and can instantiate an in-core NFS inode
1873 * and move the raw page into its mapping.
1875 int nfs_symlink(struct inode
*dir
, struct dentry
*dentry
, const char *symname
)
1880 unsigned int pathlen
= strlen(symname
);
1883 dfprintk(VFS
, "NFS: symlink(%s/%lu, %pd, %s)\n", dir
->i_sb
->s_id
,
1884 dir
->i_ino
, dentry
, symname
);
1886 if (pathlen
> PAGE_SIZE
)
1887 return -ENAMETOOLONG
;
1889 attr
.ia_mode
= S_IFLNK
| S_IRWXUGO
;
1890 attr
.ia_valid
= ATTR_MODE
;
1892 page
= alloc_page(GFP_HIGHUSER
);
1896 kaddr
= kmap_atomic(page
);
1897 memcpy(kaddr
, symname
, pathlen
);
1898 if (pathlen
< PAGE_SIZE
)
1899 memset(kaddr
+ pathlen
, 0, PAGE_SIZE
- pathlen
);
1900 kunmap_atomic(kaddr
);
1902 trace_nfs_symlink_enter(dir
, dentry
);
1903 error
= NFS_PROTO(dir
)->symlink(dir
, dentry
, page
, pathlen
, &attr
);
1904 trace_nfs_symlink_exit(dir
, dentry
, error
);
1906 dfprintk(VFS
, "NFS: symlink(%s/%lu, %pd, %s) error %d\n",
1907 dir
->i_sb
->s_id
, dir
->i_ino
,
1908 dentry
, symname
, error
);
1915 * No big deal if we can't add this page to the page cache here.
1916 * READLINK will get the missing page from the server if needed.
1918 if (!add_to_page_cache_lru(page
, dentry
->d_inode
->i_mapping
, 0,
1920 SetPageUptodate(page
);
1923 * add_to_page_cache_lru() grabs an extra page refcount.
1924 * Drop it here to avoid leaking this page later.
1926 page_cache_release(page
);
1932 EXPORT_SYMBOL_GPL(nfs_symlink
);
1935 nfs_link(struct dentry
*old_dentry
, struct inode
*dir
, struct dentry
*dentry
)
1937 struct inode
*inode
= old_dentry
->d_inode
;
1940 dfprintk(VFS
, "NFS: link(%pd2 -> %pd2)\n",
1941 old_dentry
, dentry
);
1943 trace_nfs_link_enter(inode
, dir
, dentry
);
1944 NFS_PROTO(inode
)->return_delegation(inode
);
1947 error
= NFS_PROTO(dir
)->link(inode
, dir
, &dentry
->d_name
);
1950 d_add(dentry
, inode
);
1952 trace_nfs_link_exit(inode
, dir
, dentry
, error
);
1955 EXPORT_SYMBOL_GPL(nfs_link
);
1959 * FIXME: Some nfsds, like the Linux user space nfsd, may generate a
1960 * different file handle for the same inode after a rename (e.g. when
1961 * moving to a different directory). A fail-safe method to do so would
1962 * be to look up old_dir/old_name, create a link to new_dir/new_name and
1963 * rename the old file using the sillyrename stuff. This way, the original
1964 * file in old_dir will go away when the last process iput()s the inode.
1968 * It actually works quite well. One needs to have the possibility for
1969 * at least one ".nfs..." file in each directory the file ever gets
1970 * moved or linked to which happens automagically with the new
1971 * implementation that only depends on the dcache stuff instead of
1972 * using the inode layer
1974 * Unfortunately, things are a little more complicated than indicated
1975 * above. For a cross-directory move, we want to make sure we can get
1976 * rid of the old inode after the operation. This means there must be
1977 * no pending writes (if it's a file), and the use count must be 1.
1978 * If these conditions are met, we can drop the dentries before doing
1981 int nfs_rename(struct inode
*old_dir
, struct dentry
*old_dentry
,
1982 struct inode
*new_dir
, struct dentry
*new_dentry
)
1984 struct inode
*old_inode
= old_dentry
->d_inode
;
1985 struct inode
*new_inode
= new_dentry
->d_inode
;
1986 struct dentry
*dentry
= NULL
, *rehash
= NULL
;
1987 struct rpc_task
*task
;
1990 dfprintk(VFS
, "NFS: rename(%pd2 -> %pd2, ct=%d)\n",
1991 old_dentry
, new_dentry
,
1992 d_count(new_dentry
));
1994 trace_nfs_rename_enter(old_dir
, old_dentry
, new_dir
, new_dentry
);
1996 * For non-directories, check whether the target is busy and if so,
1997 * make a copy of the dentry and then do a silly-rename. If the
1998 * silly-rename succeeds, the copied dentry is hashed and becomes
2001 if (new_inode
&& !S_ISDIR(new_inode
->i_mode
)) {
2003 * To prevent any new references to the target during the
2004 * rename, we unhash the dentry in advance.
2006 if (!d_unhashed(new_dentry
)) {
2008 rehash
= new_dentry
;
2011 if (d_count(new_dentry
) > 2) {
2014 /* copy the target dentry's name */
2015 dentry
= d_alloc(new_dentry
->d_parent
,
2016 &new_dentry
->d_name
);
2020 /* silly-rename the existing target ... */
2021 err
= nfs_sillyrename(new_dir
, new_dentry
);
2025 new_dentry
= dentry
;
2031 NFS_PROTO(old_inode
)->return_delegation(old_inode
);
2032 if (new_inode
!= NULL
)
2033 NFS_PROTO(new_inode
)->return_delegation(new_inode
);
2035 task
= nfs_async_rename(old_dir
, new_dir
, old_dentry
, new_dentry
, NULL
);
2037 error
= PTR_ERR(task
);
2041 error
= rpc_wait_for_completion_task(task
);
2043 error
= task
->tk_status
;
2045 nfs_mark_for_revalidate(old_inode
);
2049 trace_nfs_rename_exit(old_dir
, old_dentry
,
2050 new_dir
, new_dentry
, error
);
2052 if (new_inode
!= NULL
)
2053 nfs_drop_nlink(new_inode
);
2054 d_move(old_dentry
, new_dentry
);
2055 nfs_set_verifier(new_dentry
,
2056 nfs_save_change_attribute(new_dir
));
2057 } else if (error
== -ENOENT
)
2058 nfs_dentry_handle_enoent(old_dentry
);
2060 /* new dentry created? */
2065 EXPORT_SYMBOL_GPL(nfs_rename
);
2067 static DEFINE_SPINLOCK(nfs_access_lru_lock
);
2068 static LIST_HEAD(nfs_access_lru_list
);
2069 static atomic_long_t nfs_access_nr_entries
;
2071 static unsigned long nfs_access_max_cachesize
= ULONG_MAX
;
2072 module_param(nfs_access_max_cachesize
, ulong
, 0644);
2073 MODULE_PARM_DESC(nfs_access_max_cachesize
, "NFS access maximum total cache length");
2075 static void nfs_access_free_entry(struct nfs_access_entry
*entry
)
2077 put_rpccred(entry
->cred
);
2078 kfree_rcu(entry
, rcu_head
);
2079 smp_mb__before_atomic();
2080 atomic_long_dec(&nfs_access_nr_entries
);
2081 smp_mb__after_atomic();
2084 static void nfs_access_free_list(struct list_head
*head
)
2086 struct nfs_access_entry
*cache
;
2088 while (!list_empty(head
)) {
2089 cache
= list_entry(head
->next
, struct nfs_access_entry
, lru
);
2090 list_del(&cache
->lru
);
2091 nfs_access_free_entry(cache
);
2095 static unsigned long
2096 nfs_do_access_cache_scan(unsigned int nr_to_scan
)
2099 struct nfs_inode
*nfsi
, *next
;
2100 struct nfs_access_entry
*cache
;
2103 spin_lock(&nfs_access_lru_lock
);
2104 list_for_each_entry_safe(nfsi
, next
, &nfs_access_lru_list
, access_cache_inode_lru
) {
2105 struct inode
*inode
;
2107 if (nr_to_scan
-- == 0)
2109 inode
= &nfsi
->vfs_inode
;
2110 spin_lock(&inode
->i_lock
);
2111 if (list_empty(&nfsi
->access_cache_entry_lru
))
2112 goto remove_lru_entry
;
2113 cache
= list_entry(nfsi
->access_cache_entry_lru
.next
,
2114 struct nfs_access_entry
, lru
);
2115 list_move(&cache
->lru
, &head
);
2116 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
2118 if (!list_empty(&nfsi
->access_cache_entry_lru
))
2119 list_move_tail(&nfsi
->access_cache_inode_lru
,
2120 &nfs_access_lru_list
);
2123 list_del_init(&nfsi
->access_cache_inode_lru
);
2124 smp_mb__before_atomic();
2125 clear_bit(NFS_INO_ACL_LRU_SET
, &nfsi
->flags
);
2126 smp_mb__after_atomic();
2128 spin_unlock(&inode
->i_lock
);
2130 spin_unlock(&nfs_access_lru_lock
);
2131 nfs_access_free_list(&head
);
2136 nfs_access_cache_scan(struct shrinker
*shrink
, struct shrink_control
*sc
)
2138 int nr_to_scan
= sc
->nr_to_scan
;
2139 gfp_t gfp_mask
= sc
->gfp_mask
;
2141 if ((gfp_mask
& GFP_KERNEL
) != GFP_KERNEL
)
2143 return nfs_do_access_cache_scan(nr_to_scan
);
2148 nfs_access_cache_count(struct shrinker
*shrink
, struct shrink_control
*sc
)
2150 return vfs_pressure_ratio(atomic_long_read(&nfs_access_nr_entries
));
2154 nfs_access_cache_enforce_limit(void)
2156 long nr_entries
= atomic_long_read(&nfs_access_nr_entries
);
2158 unsigned int nr_to_scan
;
2160 if (nr_entries
< 0 || nr_entries
<= nfs_access_max_cachesize
)
2163 diff
= nr_entries
- nfs_access_max_cachesize
;
2164 if (diff
< nr_to_scan
)
2166 nfs_do_access_cache_scan(nr_to_scan
);
2169 static void __nfs_access_zap_cache(struct nfs_inode
*nfsi
, struct list_head
*head
)
2171 struct rb_root
*root_node
= &nfsi
->access_cache
;
2173 struct nfs_access_entry
*entry
;
2175 /* Unhook entries from the cache */
2176 while ((n
= rb_first(root_node
)) != NULL
) {
2177 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
2178 rb_erase(n
, root_node
);
2179 list_move(&entry
->lru
, head
);
2181 nfsi
->cache_validity
&= ~NFS_INO_INVALID_ACCESS
;
2184 void nfs_access_zap_cache(struct inode
*inode
)
2188 if (test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
) == 0)
2190 /* Remove from global LRU init */
2191 spin_lock(&nfs_access_lru_lock
);
2192 if (test_and_clear_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
2193 list_del_init(&NFS_I(inode
)->access_cache_inode_lru
);
2195 spin_lock(&inode
->i_lock
);
2196 __nfs_access_zap_cache(NFS_I(inode
), &head
);
2197 spin_unlock(&inode
->i_lock
);
2198 spin_unlock(&nfs_access_lru_lock
);
2199 nfs_access_free_list(&head
);
2201 EXPORT_SYMBOL_GPL(nfs_access_zap_cache
);
2203 static struct nfs_access_entry
*nfs_access_search_rbtree(struct inode
*inode
, struct rpc_cred
*cred
)
2205 struct rb_node
*n
= NFS_I(inode
)->access_cache
.rb_node
;
2206 struct nfs_access_entry
*entry
;
2209 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
2211 if (cred
< entry
->cred
)
2213 else if (cred
> entry
->cred
)
2221 static int nfs_access_get_cached(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_access_entry
*res
)
2223 struct nfs_inode
*nfsi
= NFS_I(inode
);
2224 struct nfs_access_entry
*cache
;
2227 spin_lock(&inode
->i_lock
);
2228 if (nfsi
->cache_validity
& NFS_INO_INVALID_ACCESS
)
2230 cache
= nfs_access_search_rbtree(inode
, cred
);
2233 if (!nfs_have_delegated_attributes(inode
) &&
2234 !time_in_range_open(jiffies
, cache
->jiffies
, cache
->jiffies
+ nfsi
->attrtimeo
))
2236 res
->jiffies
= cache
->jiffies
;
2237 res
->cred
= cache
->cred
;
2238 res
->mask
= cache
->mask
;
2239 list_move_tail(&cache
->lru
, &nfsi
->access_cache_entry_lru
);
2242 spin_unlock(&inode
->i_lock
);
2245 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
2246 list_del(&cache
->lru
);
2247 spin_unlock(&inode
->i_lock
);
2248 nfs_access_free_entry(cache
);
2251 spin_unlock(&inode
->i_lock
);
2252 nfs_access_zap_cache(inode
);
2256 static int nfs_access_get_cached_rcu(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_access_entry
*res
)
2258 /* Only check the most recently returned cache entry,
2259 * but do it without locking.
2261 struct nfs_inode
*nfsi
= NFS_I(inode
);
2262 struct nfs_access_entry
*cache
;
2264 struct list_head
*lh
;
2267 if (nfsi
->cache_validity
& NFS_INO_INVALID_ACCESS
)
2269 lh
= rcu_dereference(nfsi
->access_cache_entry_lru
.prev
);
2270 cache
= list_entry(lh
, struct nfs_access_entry
, lru
);
2271 if (lh
== &nfsi
->access_cache_entry_lru
||
2272 cred
!= cache
->cred
)
2276 if (!nfs_have_delegated_attributes(inode
) &&
2277 !time_in_range_open(jiffies
, cache
->jiffies
, cache
->jiffies
+ nfsi
->attrtimeo
))
2279 res
->jiffies
= cache
->jiffies
;
2280 res
->cred
= cache
->cred
;
2281 res
->mask
= cache
->mask
;
2288 static void nfs_access_add_rbtree(struct inode
*inode
, struct nfs_access_entry
*set
)
2290 struct nfs_inode
*nfsi
= NFS_I(inode
);
2291 struct rb_root
*root_node
= &nfsi
->access_cache
;
2292 struct rb_node
**p
= &root_node
->rb_node
;
2293 struct rb_node
*parent
= NULL
;
2294 struct nfs_access_entry
*entry
;
2296 spin_lock(&inode
->i_lock
);
2297 while (*p
!= NULL
) {
2299 entry
= rb_entry(parent
, struct nfs_access_entry
, rb_node
);
2301 if (set
->cred
< entry
->cred
)
2302 p
= &parent
->rb_left
;
2303 else if (set
->cred
> entry
->cred
)
2304 p
= &parent
->rb_right
;
2308 rb_link_node(&set
->rb_node
, parent
, p
);
2309 rb_insert_color(&set
->rb_node
, root_node
);
2310 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2311 spin_unlock(&inode
->i_lock
);
2314 rb_replace_node(parent
, &set
->rb_node
, root_node
);
2315 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2316 list_del(&entry
->lru
);
2317 spin_unlock(&inode
->i_lock
);
2318 nfs_access_free_entry(entry
);
2321 void nfs_access_add_cache(struct inode
*inode
, struct nfs_access_entry
*set
)
2323 struct nfs_access_entry
*cache
= kmalloc(sizeof(*cache
), GFP_KERNEL
);
2326 RB_CLEAR_NODE(&cache
->rb_node
);
2327 cache
->jiffies
= set
->jiffies
;
2328 cache
->cred
= get_rpccred(set
->cred
);
2329 cache
->mask
= set
->mask
;
2331 /* The above field assignments must be visible
2332 * before this item appears on the lru. We cannot easily
2333 * use rcu_assign_pointer, so just force the memory barrier.
2336 nfs_access_add_rbtree(inode
, cache
);
2338 /* Update accounting */
2339 smp_mb__before_atomic();
2340 atomic_long_inc(&nfs_access_nr_entries
);
2341 smp_mb__after_atomic();
2343 /* Add inode to global LRU list */
2344 if (!test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
)) {
2345 spin_lock(&nfs_access_lru_lock
);
2346 if (!test_and_set_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
2347 list_add_tail(&NFS_I(inode
)->access_cache_inode_lru
,
2348 &nfs_access_lru_list
);
2349 spin_unlock(&nfs_access_lru_lock
);
2351 nfs_access_cache_enforce_limit();
2353 EXPORT_SYMBOL_GPL(nfs_access_add_cache
);
2355 void nfs_access_set_mask(struct nfs_access_entry
*entry
, u32 access_result
)
2358 if (access_result
& NFS4_ACCESS_READ
)
2359 entry
->mask
|= MAY_READ
;
2361 (NFS4_ACCESS_MODIFY
| NFS4_ACCESS_EXTEND
| NFS4_ACCESS_DELETE
))
2362 entry
->mask
|= MAY_WRITE
;
2363 if (access_result
& (NFS4_ACCESS_LOOKUP
|NFS4_ACCESS_EXECUTE
))
2364 entry
->mask
|= MAY_EXEC
;
2366 EXPORT_SYMBOL_GPL(nfs_access_set_mask
);
2368 static int nfs_do_access(struct inode
*inode
, struct rpc_cred
*cred
, int mask
)
2370 struct nfs_access_entry cache
;
2373 trace_nfs_access_enter(inode
);
2375 status
= nfs_access_get_cached_rcu(inode
, cred
, &cache
);
2377 status
= nfs_access_get_cached(inode
, cred
, &cache
);
2382 if (mask
& MAY_NOT_BLOCK
)
2385 /* Be clever: ask server to check for all possible rights */
2386 cache
.mask
= MAY_EXEC
| MAY_WRITE
| MAY_READ
;
2388 cache
.jiffies
= jiffies
;
2389 status
= NFS_PROTO(inode
)->access(inode
, &cache
);
2391 if (status
== -ESTALE
) {
2392 nfs_zap_caches(inode
);
2393 if (!S_ISDIR(inode
->i_mode
))
2394 set_bit(NFS_INO_STALE
, &NFS_I(inode
)->flags
);
2398 nfs_access_add_cache(inode
, &cache
);
2400 if ((mask
& ~cache
.mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) != 0)
2403 trace_nfs_access_exit(inode
, status
);
2407 static int nfs_open_permission_mask(int openflags
)
2411 if (openflags
& __FMODE_EXEC
) {
2412 /* ONLY check exec rights */
2415 if ((openflags
& O_ACCMODE
) != O_WRONLY
)
2417 if ((openflags
& O_ACCMODE
) != O_RDONLY
)
2424 int nfs_may_open(struct inode
*inode
, struct rpc_cred
*cred
, int openflags
)
2426 return nfs_do_access(inode
, cred
, nfs_open_permission_mask(openflags
));
2428 EXPORT_SYMBOL_GPL(nfs_may_open
);
2430 int nfs_permission(struct inode
*inode
, int mask
)
2432 struct rpc_cred
*cred
;
2435 nfs_inc_stats(inode
, NFSIOS_VFSACCESS
);
2437 if ((mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) == 0)
2439 /* Is this sys_access() ? */
2440 if (mask
& (MAY_ACCESS
| MAY_CHDIR
))
2443 switch (inode
->i_mode
& S_IFMT
) {
2450 * Optimize away all write operations, since the server
2451 * will check permissions when we perform the op.
2453 if ((mask
& MAY_WRITE
) && !(mask
& MAY_READ
))
2458 if (!NFS_PROTO(inode
)->access
)
2461 /* Always try fast lookups first */
2463 cred
= rpc_lookup_cred_nonblock();
2465 res
= nfs_do_access(inode
, cred
, mask
|MAY_NOT_BLOCK
);
2467 res
= PTR_ERR(cred
);
2469 if (res
== -ECHILD
&& !(mask
& MAY_NOT_BLOCK
)) {
2470 /* Fast lookup failed, try the slow way */
2471 cred
= rpc_lookup_cred();
2472 if (!IS_ERR(cred
)) {
2473 res
= nfs_do_access(inode
, cred
, mask
);
2476 res
= PTR_ERR(cred
);
2479 if (!res
&& (mask
& MAY_EXEC
) && !execute_ok(inode
))
2482 dfprintk(VFS
, "NFS: permission(%s/%lu), mask=0x%x, res=%d\n",
2483 inode
->i_sb
->s_id
, inode
->i_ino
, mask
, res
);
2486 if (mask
& MAY_NOT_BLOCK
)
2489 res
= nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
2491 res
= generic_permission(inode
, mask
);
2494 EXPORT_SYMBOL_GPL(nfs_permission
);
2498 * version-control: t
2499 * kept-new-versions: 5