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/time.h>
21 #include <linux/errno.h>
22 #include <linux/stat.h>
23 #include <linux/fcntl.h>
24 #include <linux/string.h>
25 #include <linux/kernel.h>
26 #include <linux/slab.h>
28 #include <linux/sunrpc/clnt.h>
29 #include <linux/nfs_fs.h>
30 #include <linux/nfs_mount.h>
31 #include <linux/pagemap.h>
32 #include <linux/pagevec.h>
33 #include <linux/namei.h>
34 #include <linux/mount.h>
35 #include <linux/sched.h>
36 #include <linux/kmemleak.h>
37 #include <linux/xattr.h>
39 #include "delegation.h"
44 /* #define NFS_DEBUG_VERBOSE 1 */
46 static int nfs_opendir(struct inode
*, struct file
*);
47 static int nfs_closedir(struct inode
*, struct file
*);
48 static int nfs_readdir(struct file
*, void *, filldir_t
);
49 static int nfs_fsync_dir(struct file
*, loff_t
, loff_t
, int);
50 static loff_t
nfs_llseek_dir(struct file
*, loff_t
, int);
51 static void nfs_readdir_clear_array(struct page
*);
53 const struct file_operations nfs_dir_operations
= {
54 .llseek
= nfs_llseek_dir
,
55 .read
= generic_read_dir
,
56 .readdir
= nfs_readdir
,
58 .release
= nfs_closedir
,
59 .fsync
= nfs_fsync_dir
,
62 const struct address_space_operations nfs_dir_aops
= {
63 .freepage
= nfs_readdir_clear_array
,
66 static struct nfs_open_dir_context
*alloc_nfs_open_dir_context(struct inode
*dir
, struct rpc_cred
*cred
)
68 struct nfs_open_dir_context
*ctx
;
69 ctx
= kmalloc(sizeof(*ctx
), GFP_KERNEL
);
72 ctx
->attr_gencount
= NFS_I(dir
)->attr_gencount
;
75 ctx
->cred
= get_rpccred(cred
);
78 return ERR_PTR(-ENOMEM
);
81 static void put_nfs_open_dir_context(struct nfs_open_dir_context
*ctx
)
83 put_rpccred(ctx
->cred
);
91 nfs_opendir(struct inode
*inode
, struct file
*filp
)
94 struct nfs_open_dir_context
*ctx
;
95 struct rpc_cred
*cred
;
97 dfprintk(FILE, "NFS: open dir(%s/%s)\n",
98 filp
->f_path
.dentry
->d_parent
->d_name
.name
,
99 filp
->f_path
.dentry
->d_name
.name
);
101 nfs_inc_stats(inode
, NFSIOS_VFSOPEN
);
103 cred
= rpc_lookup_cred();
105 return PTR_ERR(cred
);
106 ctx
= alloc_nfs_open_dir_context(inode
, cred
);
111 filp
->private_data
= ctx
;
112 if (filp
->f_path
.dentry
== filp
->f_path
.mnt
->mnt_root
) {
113 /* This is a mountpoint, so d_revalidate will never
114 * have been called, so we need to refresh the
115 * inode (for close-open consistency) ourselves.
117 __nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
125 nfs_closedir(struct inode
*inode
, struct file
*filp
)
127 put_nfs_open_dir_context(filp
->private_data
);
131 struct nfs_cache_array_entry
{
135 unsigned char d_type
;
138 struct nfs_cache_array
{
142 struct nfs_cache_array_entry array
[0];
145 typedef int (*decode_dirent_t
)(struct xdr_stream
*, struct nfs_entry
*, int);
149 unsigned long page_index
;
152 loff_t current_index
;
153 decode_dirent_t decode
;
155 unsigned long timestamp
;
156 unsigned long gencount
;
157 unsigned int cache_entry_index
;
160 } nfs_readdir_descriptor_t
;
163 * The caller is responsible for calling nfs_readdir_release_array(page)
166 struct nfs_cache_array
*nfs_readdir_get_array(struct page
*page
)
170 return ERR_PTR(-EIO
);
173 return ERR_PTR(-ENOMEM
);
178 void nfs_readdir_release_array(struct page
*page
)
184 * we are freeing strings created by nfs_add_to_readdir_array()
187 void nfs_readdir_clear_array(struct page
*page
)
189 struct nfs_cache_array
*array
;
192 array
= kmap_atomic(page
);
193 for (i
= 0; i
< array
->size
; i
++)
194 kfree(array
->array
[i
].string
.name
);
195 kunmap_atomic(array
);
199 * the caller is responsible for freeing qstr.name
200 * when called by nfs_readdir_add_to_array, the strings will be freed in
201 * nfs_clear_readdir_array()
204 int nfs_readdir_make_qstr(struct qstr
*string
, const char *name
, unsigned int len
)
207 string
->name
= kmemdup(name
, len
, GFP_KERNEL
);
208 if (string
->name
== NULL
)
211 * Avoid a kmemleak false positive. The pointer to the name is stored
212 * in a page cache page which kmemleak does not scan.
214 kmemleak_not_leak(string
->name
);
215 string
->hash
= full_name_hash(name
, len
);
220 int nfs_readdir_add_to_array(struct nfs_entry
*entry
, struct page
*page
)
222 struct nfs_cache_array
*array
= nfs_readdir_get_array(page
);
223 struct nfs_cache_array_entry
*cache_entry
;
227 return PTR_ERR(array
);
229 cache_entry
= &array
->array
[array
->size
];
231 /* Check that this entry lies within the page bounds */
233 if ((char *)&cache_entry
[1] - (char *)page_address(page
) > PAGE_SIZE
)
236 cache_entry
->cookie
= entry
->prev_cookie
;
237 cache_entry
->ino
= entry
->ino
;
238 cache_entry
->d_type
= entry
->d_type
;
239 ret
= nfs_readdir_make_qstr(&cache_entry
->string
, entry
->name
, entry
->len
);
242 array
->last_cookie
= entry
->cookie
;
245 array
->eof_index
= array
->size
;
247 nfs_readdir_release_array(page
);
252 int nfs_readdir_search_for_pos(struct nfs_cache_array
*array
, nfs_readdir_descriptor_t
*desc
)
254 loff_t diff
= desc
->file
->f_pos
- desc
->current_index
;
259 if (diff
>= array
->size
) {
260 if (array
->eof_index
>= 0)
265 index
= (unsigned int)diff
;
266 *desc
->dir_cookie
= array
->array
[index
].cookie
;
267 desc
->cache_entry_index
= index
;
275 int nfs_readdir_search_for_cookie(struct nfs_cache_array
*array
, nfs_readdir_descriptor_t
*desc
)
279 int status
= -EAGAIN
;
281 for (i
= 0; i
< array
->size
; i
++) {
282 if (array
->array
[i
].cookie
== *desc
->dir_cookie
) {
283 struct nfs_inode
*nfsi
= NFS_I(desc
->file
->f_path
.dentry
->d_inode
);
284 struct nfs_open_dir_context
*ctx
= desc
->file
->private_data
;
286 new_pos
= desc
->current_index
+ i
;
287 if (ctx
->attr_gencount
!= nfsi
->attr_gencount
288 || (nfsi
->cache_validity
& (NFS_INO_INVALID_ATTR
|NFS_INO_INVALID_DATA
))) {
290 ctx
->attr_gencount
= nfsi
->attr_gencount
;
291 } else if (new_pos
< desc
->file
->f_pos
) {
293 && ctx
->dup_cookie
== *desc
->dir_cookie
) {
294 if (printk_ratelimit()) {
295 pr_notice("NFS: directory %s/%s contains a readdir loop."
296 "Please contact your server vendor. "
297 "The file: %s has duplicate cookie %llu\n",
298 desc
->file
->f_dentry
->d_parent
->d_name
.name
,
299 desc
->file
->f_dentry
->d_name
.name
,
300 array
->array
[i
].string
.name
,
306 ctx
->dup_cookie
= *desc
->dir_cookie
;
309 desc
->file
->f_pos
= new_pos
;
310 desc
->cache_entry_index
= i
;
314 if (array
->eof_index
>= 0) {
315 status
= -EBADCOOKIE
;
316 if (*desc
->dir_cookie
== array
->last_cookie
)
324 int nfs_readdir_search_array(nfs_readdir_descriptor_t
*desc
)
326 struct nfs_cache_array
*array
;
329 array
= nfs_readdir_get_array(desc
->page
);
331 status
= PTR_ERR(array
);
335 if (*desc
->dir_cookie
== 0)
336 status
= nfs_readdir_search_for_pos(array
, desc
);
338 status
= nfs_readdir_search_for_cookie(array
, desc
);
340 if (status
== -EAGAIN
) {
341 desc
->last_cookie
= array
->last_cookie
;
342 desc
->current_index
+= array
->size
;
345 nfs_readdir_release_array(desc
->page
);
350 /* Fill a page with xdr information before transferring to the cache page */
352 int nfs_readdir_xdr_filler(struct page
**pages
, nfs_readdir_descriptor_t
*desc
,
353 struct nfs_entry
*entry
, struct file
*file
, struct inode
*inode
)
355 struct nfs_open_dir_context
*ctx
= file
->private_data
;
356 struct rpc_cred
*cred
= ctx
->cred
;
357 unsigned long timestamp
, gencount
;
362 gencount
= nfs_inc_attr_generation_counter();
363 error
= NFS_PROTO(inode
)->readdir(file
->f_path
.dentry
, cred
, entry
->cookie
, pages
,
364 NFS_SERVER(inode
)->dtsize
, desc
->plus
);
366 /* We requested READDIRPLUS, but the server doesn't grok it */
367 if (error
== -ENOTSUPP
&& desc
->plus
) {
368 NFS_SERVER(inode
)->caps
&= ~NFS_CAP_READDIRPLUS
;
369 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
375 desc
->timestamp
= timestamp
;
376 desc
->gencount
= gencount
;
381 static int xdr_decode(nfs_readdir_descriptor_t
*desc
,
382 struct nfs_entry
*entry
, struct xdr_stream
*xdr
)
386 error
= desc
->decode(xdr
, entry
, desc
->plus
);
389 entry
->fattr
->time_start
= desc
->timestamp
;
390 entry
->fattr
->gencount
= desc
->gencount
;
395 int nfs_same_file(struct dentry
*dentry
, struct nfs_entry
*entry
)
397 if (dentry
->d_inode
== NULL
)
399 if (nfs_compare_fh(entry
->fh
, NFS_FH(dentry
->d_inode
)) != 0)
407 bool nfs_use_readdirplus(struct inode
*dir
, struct file
*filp
)
409 if (!nfs_server_capable(dir
, NFS_CAP_READDIRPLUS
))
411 if (test_and_clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(dir
)->flags
))
413 if (filp
->f_pos
== 0)
419 * This function is called by the lookup code to request the use of
420 * readdirplus to accelerate any future lookups in the same
424 void nfs_advise_use_readdirplus(struct inode
*dir
)
426 set_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(dir
)->flags
);
430 void nfs_prime_dcache(struct dentry
*parent
, struct nfs_entry
*entry
)
432 struct qstr filename
= QSTR_INIT(entry
->name
, entry
->len
);
433 struct dentry
*dentry
;
434 struct dentry
*alias
;
435 struct inode
*dir
= parent
->d_inode
;
438 if (filename
.name
[0] == '.') {
439 if (filename
.len
== 1)
441 if (filename
.len
== 2 && filename
.name
[1] == '.')
444 filename
.hash
= full_name_hash(filename
.name
, filename
.len
);
446 dentry
= d_lookup(parent
, &filename
);
447 if (dentry
!= NULL
) {
448 if (nfs_same_file(dentry
, entry
)) {
449 nfs_refresh_inode(dentry
->d_inode
, entry
->fattr
);
457 dentry
= d_alloc(parent
, &filename
);
461 inode
= nfs_fhget(dentry
->d_sb
, entry
->fh
, entry
->fattr
);
465 alias
= d_materialise_unique(dentry
, inode
);
469 nfs_set_verifier(alias
, nfs_save_change_attribute(dir
));
472 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
478 /* Perform conversion from xdr to cache array */
480 int nfs_readdir_page_filler(nfs_readdir_descriptor_t
*desc
, struct nfs_entry
*entry
,
481 struct page
**xdr_pages
, struct page
*page
, unsigned int buflen
)
483 struct xdr_stream stream
;
485 struct page
*scratch
;
486 struct nfs_cache_array
*array
;
487 unsigned int count
= 0;
490 scratch
= alloc_page(GFP_KERNEL
);
494 xdr_init_decode_pages(&stream
, &buf
, xdr_pages
, buflen
);
495 xdr_set_scratch_buffer(&stream
, page_address(scratch
), PAGE_SIZE
);
498 status
= xdr_decode(desc
, entry
, &stream
);
500 if (status
== -EAGAIN
)
508 nfs_prime_dcache(desc
->file
->f_path
.dentry
, entry
);
510 status
= nfs_readdir_add_to_array(entry
, page
);
513 } while (!entry
->eof
);
515 if (count
== 0 || (status
== -EBADCOOKIE
&& entry
->eof
!= 0)) {
516 array
= nfs_readdir_get_array(page
);
517 if (!IS_ERR(array
)) {
518 array
->eof_index
= array
->size
;
520 nfs_readdir_release_array(page
);
522 status
= PTR_ERR(array
);
530 void nfs_readdir_free_pagearray(struct page
**pages
, unsigned int npages
)
533 for (i
= 0; i
< npages
; i
++)
538 void nfs_readdir_free_large_page(void *ptr
, struct page
**pages
,
541 nfs_readdir_free_pagearray(pages
, npages
);
545 * nfs_readdir_large_page will allocate pages that must be freed with a call
546 * to nfs_readdir_free_large_page
549 int nfs_readdir_large_page(struct page
**pages
, unsigned int npages
)
553 for (i
= 0; i
< npages
; i
++) {
554 struct page
*page
= alloc_page(GFP_KERNEL
);
562 nfs_readdir_free_pagearray(pages
, i
);
567 int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t
*desc
, struct page
*page
, struct inode
*inode
)
569 struct page
*pages
[NFS_MAX_READDIR_PAGES
];
570 void *pages_ptr
= NULL
;
571 struct nfs_entry entry
;
572 struct file
*file
= desc
->file
;
573 struct nfs_cache_array
*array
;
574 int status
= -ENOMEM
;
575 unsigned int array_size
= ARRAY_SIZE(pages
);
577 entry
.prev_cookie
= 0;
578 entry
.cookie
= desc
->last_cookie
;
580 entry
.fh
= nfs_alloc_fhandle();
581 entry
.fattr
= nfs_alloc_fattr();
582 entry
.server
= NFS_SERVER(inode
);
583 if (entry
.fh
== NULL
|| entry
.fattr
== NULL
)
586 array
= nfs_readdir_get_array(page
);
588 status
= PTR_ERR(array
);
591 memset(array
, 0, sizeof(struct nfs_cache_array
));
592 array
->eof_index
= -1;
594 status
= nfs_readdir_large_page(pages
, array_size
);
596 goto out_release_array
;
599 status
= nfs_readdir_xdr_filler(pages
, desc
, &entry
, file
, inode
);
604 status
= nfs_readdir_page_filler(desc
, &entry
, pages
, page
, pglen
);
606 if (status
== -ENOSPC
)
610 } while (array
->eof_index
< 0);
612 nfs_readdir_free_large_page(pages_ptr
, pages
, array_size
);
614 nfs_readdir_release_array(page
);
616 nfs_free_fattr(entry
.fattr
);
617 nfs_free_fhandle(entry
.fh
);
622 * Now we cache directories properly, by converting xdr information
623 * to an array that can be used for lookups later. This results in
624 * fewer cache pages, since we can store more information on each page.
625 * We only need to convert from xdr once so future lookups are much simpler
628 int nfs_readdir_filler(nfs_readdir_descriptor_t
*desc
, struct page
* page
)
630 struct inode
*inode
= desc
->file
->f_path
.dentry
->d_inode
;
633 ret
= nfs_readdir_xdr_to_array(desc
, page
, inode
);
636 SetPageUptodate(page
);
638 if (invalidate_inode_pages2_range(inode
->i_mapping
, page
->index
+ 1, -1) < 0) {
639 /* Should never happen */
640 nfs_zap_mapping(inode
, inode
->i_mapping
);
650 void cache_page_release(nfs_readdir_descriptor_t
*desc
)
652 if (!desc
->page
->mapping
)
653 nfs_readdir_clear_array(desc
->page
);
654 page_cache_release(desc
->page
);
659 struct page
*get_cache_page(nfs_readdir_descriptor_t
*desc
)
661 return read_cache_page(desc
->file
->f_path
.dentry
->d_inode
->i_mapping
,
662 desc
->page_index
, (filler_t
*)nfs_readdir_filler
, desc
);
666 * Returns 0 if desc->dir_cookie was found on page desc->page_index
669 int find_cache_page(nfs_readdir_descriptor_t
*desc
)
673 desc
->page
= get_cache_page(desc
);
674 if (IS_ERR(desc
->page
))
675 return PTR_ERR(desc
->page
);
677 res
= nfs_readdir_search_array(desc
);
679 cache_page_release(desc
);
683 /* Search for desc->dir_cookie from the beginning of the page cache */
685 int readdir_search_pagecache(nfs_readdir_descriptor_t
*desc
)
689 if (desc
->page_index
== 0) {
690 desc
->current_index
= 0;
691 desc
->last_cookie
= 0;
694 res
= find_cache_page(desc
);
695 } while (res
== -EAGAIN
);
700 * Once we've found the start of the dirent within a page: fill 'er up...
703 int nfs_do_filldir(nfs_readdir_descriptor_t
*desc
, void *dirent
,
706 struct file
*file
= desc
->file
;
709 struct nfs_cache_array
*array
= NULL
;
710 struct nfs_open_dir_context
*ctx
= file
->private_data
;
712 array
= nfs_readdir_get_array(desc
->page
);
714 res
= PTR_ERR(array
);
718 for (i
= desc
->cache_entry_index
; i
< array
->size
; i
++) {
719 struct nfs_cache_array_entry
*ent
;
721 ent
= &array
->array
[i
];
722 if (filldir(dirent
, ent
->string
.name
, ent
->string
.len
,
723 file
->f_pos
, nfs_compat_user_ino64(ent
->ino
),
729 if (i
< (array
->size
-1))
730 *desc
->dir_cookie
= array
->array
[i
+1].cookie
;
732 *desc
->dir_cookie
= array
->last_cookie
;
736 if (array
->eof_index
>= 0)
739 nfs_readdir_release_array(desc
->page
);
741 cache_page_release(desc
);
742 dfprintk(DIRCACHE
, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n",
743 (unsigned long long)*desc
->dir_cookie
, res
);
748 * If we cannot find a cookie in our cache, we suspect that this is
749 * because it points to a deleted file, so we ask the server to return
750 * whatever it thinks is the next entry. We then feed this to filldir.
751 * If all goes well, we should then be able to find our way round the
752 * cache on the next call to readdir_search_pagecache();
754 * NOTE: we cannot add the anonymous page to the pagecache because
755 * the data it contains might not be page aligned. Besides,
756 * we should already have a complete representation of the
757 * directory in the page cache by the time we get here.
760 int uncached_readdir(nfs_readdir_descriptor_t
*desc
, void *dirent
,
763 struct page
*page
= NULL
;
765 struct inode
*inode
= desc
->file
->f_path
.dentry
->d_inode
;
766 struct nfs_open_dir_context
*ctx
= desc
->file
->private_data
;
768 dfprintk(DIRCACHE
, "NFS: uncached_readdir() searching for cookie %Lu\n",
769 (unsigned long long)*desc
->dir_cookie
);
771 page
= alloc_page(GFP_HIGHUSER
);
777 desc
->page_index
= 0;
778 desc
->last_cookie
= *desc
->dir_cookie
;
782 status
= nfs_readdir_xdr_to_array(desc
, page
, inode
);
786 status
= nfs_do_filldir(desc
, dirent
, filldir
);
789 dfprintk(DIRCACHE
, "NFS: %s: returns %d\n",
793 cache_page_release(desc
);
797 /* The file offset position represents the dirent entry number. A
798 last cookie cache takes care of the common case of reading the
801 static int nfs_readdir(struct file
*filp
, void *dirent
, filldir_t filldir
)
803 struct dentry
*dentry
= filp
->f_path
.dentry
;
804 struct inode
*inode
= dentry
->d_inode
;
805 nfs_readdir_descriptor_t my_desc
,
807 struct nfs_open_dir_context
*dir_ctx
= filp
->private_data
;
810 dfprintk(FILE, "NFS: readdir(%s/%s) starting at cookie %llu\n",
811 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
812 (long long)filp
->f_pos
);
813 nfs_inc_stats(inode
, NFSIOS_VFSGETDENTS
);
816 * filp->f_pos points to the dirent entry number.
817 * *desc->dir_cookie has the cookie for the next entry. We have
818 * to either find the entry with the appropriate number or
819 * revalidate the cookie.
821 memset(desc
, 0, sizeof(*desc
));
824 desc
->dir_cookie
= &dir_ctx
->dir_cookie
;
825 desc
->decode
= NFS_PROTO(inode
)->decode_dirent
;
826 desc
->plus
= nfs_use_readdirplus(inode
, filp
) ? 1 : 0;
828 nfs_block_sillyrename(dentry
);
829 res
= nfs_revalidate_mapping(inode
, filp
->f_mapping
);
834 res
= readdir_search_pagecache(desc
);
836 if (res
== -EBADCOOKIE
) {
838 /* This means either end of directory */
839 if (*desc
->dir_cookie
&& desc
->eof
== 0) {
840 /* Or that the server has 'lost' a cookie */
841 res
= uncached_readdir(desc
, dirent
, filldir
);
847 if (res
== -ETOOSMALL
&& desc
->plus
) {
848 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
849 nfs_zap_caches(inode
);
850 desc
->page_index
= 0;
858 res
= nfs_do_filldir(desc
, dirent
, filldir
);
861 } while (!desc
->eof
);
863 nfs_unblock_sillyrename(dentry
);
866 dfprintk(FILE, "NFS: readdir(%s/%s) returns %d\n",
867 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
872 static loff_t
nfs_llseek_dir(struct file
*filp
, loff_t offset
, int origin
)
874 struct dentry
*dentry
= filp
->f_path
.dentry
;
875 struct inode
*inode
= dentry
->d_inode
;
876 struct nfs_open_dir_context
*dir_ctx
= filp
->private_data
;
878 dfprintk(FILE, "NFS: llseek dir(%s/%s, %lld, %d)\n",
879 dentry
->d_parent
->d_name
.name
,
883 mutex_lock(&inode
->i_mutex
);
886 offset
+= filp
->f_pos
;
894 if (offset
!= filp
->f_pos
) {
895 filp
->f_pos
= offset
;
896 dir_ctx
->dir_cookie
= 0;
900 mutex_unlock(&inode
->i_mutex
);
905 * All directory operations under NFS are synchronous, so fsync()
906 * is a dummy operation.
908 static int nfs_fsync_dir(struct file
*filp
, loff_t start
, loff_t end
,
911 struct dentry
*dentry
= filp
->f_path
.dentry
;
912 struct inode
*inode
= dentry
->d_inode
;
914 dfprintk(FILE, "NFS: fsync dir(%s/%s) datasync %d\n",
915 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
918 mutex_lock(&inode
->i_mutex
);
919 nfs_inc_stats(dentry
->d_inode
, NFSIOS_VFSFSYNC
);
920 mutex_unlock(&inode
->i_mutex
);
925 * nfs_force_lookup_revalidate - Mark the directory as having changed
926 * @dir - pointer to directory inode
928 * This forces the revalidation code in nfs_lookup_revalidate() to do a
929 * full lookup on all child dentries of 'dir' whenever a change occurs
930 * on the server that might have invalidated our dcache.
932 * The caller should be holding dir->i_lock
934 void nfs_force_lookup_revalidate(struct inode
*dir
)
936 NFS_I(dir
)->cache_change_attribute
++;
940 * A check for whether or not the parent directory has changed.
941 * In the case it has, we assume that the dentries are untrustworthy
942 * and may need to be looked up again.
944 static int nfs_check_verifier(struct inode
*dir
, struct dentry
*dentry
)
948 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONE
)
950 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
952 /* Revalidate nfsi->cache_change_attribute before we declare a match */
953 if (nfs_revalidate_inode(NFS_SERVER(dir
), dir
) < 0)
955 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
961 * Use intent information to check whether or not we're going to do
962 * an O_EXCL create using this path component.
964 static int nfs_is_exclusive_create(struct inode
*dir
, unsigned int flags
)
966 if (NFS_PROTO(dir
)->version
== 2)
968 return flags
& LOOKUP_EXCL
;
972 * Inode and filehandle revalidation for lookups.
974 * We force revalidation in the cases where the VFS sets LOOKUP_REVAL,
975 * or if the intent information indicates that we're about to open this
976 * particular file and the "nocto" mount flag is not set.
980 int nfs_lookup_verify_inode(struct inode
*inode
, unsigned int flags
)
982 struct nfs_server
*server
= NFS_SERVER(inode
);
984 if (IS_AUTOMOUNT(inode
))
986 /* VFS wants an on-the-wire revalidation */
987 if (flags
& LOOKUP_REVAL
)
989 /* This is an open(2) */
990 if ((flags
& LOOKUP_OPEN
) && !(server
->flags
& NFS_MOUNT_NOCTO
) &&
991 (S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
)))
995 return __nfs_revalidate_inode(server
, inode
);
999 * We judge how long we want to trust negative
1000 * dentries by looking at the parent inode mtime.
1002 * If parent mtime has changed, we revalidate, else we wait for a
1003 * period corresponding to the parent's attribute cache timeout value.
1006 int nfs_neg_need_reval(struct inode
*dir
, struct dentry
*dentry
,
1009 /* Don't revalidate a negative dentry if we're creating a new file */
1010 if (flags
& LOOKUP_CREATE
)
1012 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONEG
)
1014 return !nfs_check_verifier(dir
, dentry
);
1018 * This is called every time the dcache has a lookup hit,
1019 * and we should check whether we can really trust that
1022 * NOTE! The hit can be a negative hit too, don't assume
1025 * If the parent directory is seen to have changed, we throw out the
1026 * cached dentry and do a new lookup.
1028 static int nfs_lookup_revalidate(struct dentry
*dentry
, unsigned int flags
)
1031 struct inode
*inode
;
1032 struct dentry
*parent
;
1033 struct nfs_fh
*fhandle
= NULL
;
1034 struct nfs_fattr
*fattr
= NULL
;
1037 if (flags
& LOOKUP_RCU
)
1040 parent
= dget_parent(dentry
);
1041 dir
= parent
->d_inode
;
1042 nfs_inc_stats(dir
, NFSIOS_DENTRYREVALIDATE
);
1043 inode
= dentry
->d_inode
;
1046 if (nfs_neg_need_reval(dir
, dentry
, flags
))
1048 goto out_valid_noent
;
1051 if (is_bad_inode(inode
)) {
1052 dfprintk(LOOKUPCACHE
, "%s: %s/%s has dud inode\n",
1053 __func__
, dentry
->d_parent
->d_name
.name
,
1054 dentry
->d_name
.name
);
1058 if (NFS_PROTO(dir
)->have_delegation(inode
, FMODE_READ
))
1059 goto out_set_verifier
;
1061 /* Force a full look up iff the parent directory has changed */
1062 if (!nfs_is_exclusive_create(dir
, flags
) && nfs_check_verifier(dir
, dentry
)) {
1063 if (nfs_lookup_verify_inode(inode
, flags
))
1064 goto out_zap_parent
;
1068 if (NFS_STALE(inode
))
1072 fhandle
= nfs_alloc_fhandle();
1073 fattr
= nfs_alloc_fattr();
1074 if (fhandle
== NULL
|| fattr
== NULL
)
1077 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
);
1080 if (nfs_compare_fh(NFS_FH(inode
), fhandle
))
1082 if ((error
= nfs_refresh_inode(inode
, fattr
)) != 0)
1085 nfs_free_fattr(fattr
);
1086 nfs_free_fhandle(fhandle
);
1088 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1090 /* Success: notify readdir to use READDIRPLUS */
1091 nfs_advise_use_readdirplus(dir
);
1094 dfprintk(LOOKUPCACHE
, "NFS: %s(%s/%s) is valid\n",
1095 __func__
, dentry
->d_parent
->d_name
.name
,
1096 dentry
->d_name
.name
);
1099 nfs_zap_caches(dir
);
1101 nfs_mark_for_revalidate(dir
);
1102 if (inode
&& S_ISDIR(inode
->i_mode
)) {
1103 /* Purge readdir caches. */
1104 nfs_zap_caches(inode
);
1105 /* If we have submounts, don't unhash ! */
1106 if (have_submounts(dentry
))
1108 if (dentry
->d_flags
& DCACHE_DISCONNECTED
)
1110 shrink_dcache_parent(dentry
);
1113 nfs_free_fattr(fattr
);
1114 nfs_free_fhandle(fhandle
);
1116 dfprintk(LOOKUPCACHE
, "NFS: %s(%s/%s) is invalid\n",
1117 __func__
, dentry
->d_parent
->d_name
.name
,
1118 dentry
->d_name
.name
);
1121 nfs_free_fattr(fattr
);
1122 nfs_free_fhandle(fhandle
);
1124 dfprintk(LOOKUPCACHE
, "NFS: %s(%s/%s) lookup returned error %d\n",
1125 __func__
, dentry
->d_parent
->d_name
.name
,
1126 dentry
->d_name
.name
, error
);
1131 * This is called from dput() when d_count is going to 0.
1133 static int nfs_dentry_delete(const struct dentry
*dentry
)
1135 dfprintk(VFS
, "NFS: dentry_delete(%s/%s, %x)\n",
1136 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
1139 /* Unhash any dentry with a stale inode */
1140 if (dentry
->d_inode
!= NULL
&& NFS_STALE(dentry
->d_inode
))
1143 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1144 /* Unhash it, so that ->d_iput() would be called */
1147 if (!(dentry
->d_sb
->s_flags
& MS_ACTIVE
)) {
1148 /* Unhash it, so that ancestors of killed async unlink
1149 * files will be cleaned up during umount */
1156 static void nfs_drop_nlink(struct inode
*inode
)
1158 spin_lock(&inode
->i_lock
);
1159 if (inode
->i_nlink
> 0)
1161 spin_unlock(&inode
->i_lock
);
1165 * Called when the dentry loses inode.
1166 * We use it to clean up silly-renamed files.
1168 static void nfs_dentry_iput(struct dentry
*dentry
, struct inode
*inode
)
1170 if (S_ISDIR(inode
->i_mode
))
1171 /* drop any readdir cache as it could easily be old */
1172 NFS_I(inode
)->cache_validity
|= NFS_INO_INVALID_DATA
;
1174 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1176 nfs_complete_unlink(dentry
, inode
);
1181 static void nfs_d_release(struct dentry
*dentry
)
1183 /* free cached devname value, if it survived that far */
1184 if (unlikely(dentry
->d_fsdata
)) {
1185 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
)
1188 kfree(dentry
->d_fsdata
);
1192 const struct dentry_operations nfs_dentry_operations
= {
1193 .d_revalidate
= nfs_lookup_revalidate
,
1194 .d_delete
= nfs_dentry_delete
,
1195 .d_iput
= nfs_dentry_iput
,
1196 .d_automount
= nfs_d_automount
,
1197 .d_release
= nfs_d_release
,
1200 struct dentry
*nfs_lookup(struct inode
*dir
, struct dentry
* dentry
, unsigned int flags
)
1203 struct dentry
*parent
;
1204 struct inode
*inode
= NULL
;
1205 struct nfs_fh
*fhandle
= NULL
;
1206 struct nfs_fattr
*fattr
= NULL
;
1209 dfprintk(VFS
, "NFS: lookup(%s/%s)\n",
1210 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
1211 nfs_inc_stats(dir
, NFSIOS_VFSLOOKUP
);
1213 res
= ERR_PTR(-ENAMETOOLONG
);
1214 if (dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
)
1218 * If we're doing an exclusive create, optimize away the lookup
1219 * but don't hash the dentry.
1221 if (nfs_is_exclusive_create(dir
, flags
)) {
1222 d_instantiate(dentry
, NULL
);
1227 res
= ERR_PTR(-ENOMEM
);
1228 fhandle
= nfs_alloc_fhandle();
1229 fattr
= nfs_alloc_fattr();
1230 if (fhandle
== NULL
|| fattr
== NULL
)
1233 parent
= dentry
->d_parent
;
1234 /* Protect against concurrent sillydeletes */
1235 nfs_block_sillyrename(parent
);
1236 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
);
1237 if (error
== -ENOENT
)
1240 res
= ERR_PTR(error
);
1241 goto out_unblock_sillyrename
;
1243 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
);
1244 res
= ERR_CAST(inode
);
1246 goto out_unblock_sillyrename
;
1248 /* Success: notify readdir to use READDIRPLUS */
1249 nfs_advise_use_readdirplus(dir
);
1252 res
= d_materialise_unique(dentry
, inode
);
1255 goto out_unblock_sillyrename
;
1258 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1259 out_unblock_sillyrename
:
1260 nfs_unblock_sillyrename(parent
);
1262 nfs_free_fattr(fattr
);
1263 nfs_free_fhandle(fhandle
);
1267 #ifdef CONFIG_NFS_V4
1268 static int nfs4_lookup_revalidate(struct dentry
*, unsigned int);
1270 const struct dentry_operations nfs4_dentry_operations
= {
1271 .d_revalidate
= nfs4_lookup_revalidate
,
1272 .d_delete
= nfs_dentry_delete
,
1273 .d_iput
= nfs_dentry_iput
,
1274 .d_automount
= nfs_d_automount
,
1275 .d_release
= nfs_d_release
,
1278 static fmode_t
flags_to_mode(int flags
)
1280 fmode_t res
= (__force fmode_t
)flags
& FMODE_EXEC
;
1281 if ((flags
& O_ACCMODE
) != O_WRONLY
)
1283 if ((flags
& O_ACCMODE
) != O_RDONLY
)
1288 static struct nfs_open_context
*create_nfs_open_context(struct dentry
*dentry
, int open_flags
)
1290 return alloc_nfs_open_context(dentry
, flags_to_mode(open_flags
));
1293 static int do_open(struct inode
*inode
, struct file
*filp
)
1295 nfs_fscache_set_inode_cookie(inode
, filp
);
1299 static int nfs_finish_open(struct nfs_open_context
*ctx
,
1300 struct dentry
*dentry
,
1301 struct file
*file
, unsigned open_flags
,
1306 if (ctx
->dentry
!= dentry
) {
1308 ctx
->dentry
= dget(dentry
);
1311 /* If the open_intent is for execute, we have an extra check to make */
1312 if (ctx
->mode
& FMODE_EXEC
) {
1313 err
= nfs_may_open(dentry
->d_inode
, ctx
->cred
, open_flags
);
1318 err
= finish_open(file
, dentry
, do_open
, opened
);
1321 nfs_file_set_open_context(file
, ctx
);
1324 put_nfs_open_context(ctx
);
1328 int nfs_atomic_open(struct inode
*dir
, struct dentry
*dentry
,
1329 struct file
*file
, unsigned open_flags
,
1330 umode_t mode
, int *opened
)
1332 struct nfs_open_context
*ctx
;
1334 struct iattr attr
= { .ia_valid
= ATTR_OPEN
};
1335 struct inode
*inode
;
1338 /* Expect a negative dentry */
1339 BUG_ON(dentry
->d_inode
);
1341 dfprintk(VFS
, "NFS: atomic_open(%s/%ld), %s\n",
1342 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1344 /* NFS only supports OPEN on regular files */
1345 if ((open_flags
& O_DIRECTORY
)) {
1346 if (!d_unhashed(dentry
)) {
1348 * Hashed negative dentry with O_DIRECTORY: dentry was
1349 * revalidated and is fine, no need to perform lookup
1357 if (dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
)
1358 return -ENAMETOOLONG
;
1360 if (open_flags
& O_CREAT
) {
1361 attr
.ia_valid
|= ATTR_MODE
;
1362 attr
.ia_mode
= mode
& ~current_umask();
1364 if (open_flags
& O_TRUNC
) {
1365 attr
.ia_valid
|= ATTR_SIZE
;
1369 ctx
= create_nfs_open_context(dentry
, open_flags
);
1374 nfs_block_sillyrename(dentry
->d_parent
);
1375 inode
= NFS_PROTO(dir
)->open_context(dir
, ctx
, open_flags
, &attr
);
1377 if (IS_ERR(inode
)) {
1378 nfs_unblock_sillyrename(dentry
->d_parent
);
1379 put_nfs_open_context(ctx
);
1380 err
= PTR_ERR(inode
);
1383 d_add(dentry
, NULL
);
1389 if (!(open_flags
& O_NOFOLLOW
))
1398 res
= d_add_unique(dentry
, inode
);
1402 nfs_unblock_sillyrename(dentry
->d_parent
);
1403 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1405 err
= nfs_finish_open(ctx
, dentry
, file
, open_flags
, opened
);
1412 res
= nfs_lookup(dir
, dentry
, 0);
1417 return finish_no_open(file
, res
);
1420 static int nfs4_lookup_revalidate(struct dentry
*dentry
, unsigned int flags
)
1422 struct dentry
*parent
= NULL
;
1423 struct inode
*inode
;
1427 if (flags
& LOOKUP_RCU
)
1430 if (!(flags
& LOOKUP_OPEN
) || (flags
& LOOKUP_DIRECTORY
))
1432 if (d_mountpoint(dentry
))
1435 inode
= dentry
->d_inode
;
1436 parent
= dget_parent(dentry
);
1437 dir
= parent
->d_inode
;
1439 /* We can't create new files in nfs_open_revalidate(), so we
1440 * optimize away revalidation of negative dentries.
1442 if (inode
== NULL
) {
1443 if (!nfs_neg_need_reval(dir
, dentry
, flags
))
1448 /* NFS only supports OPEN on regular files */
1449 if (!S_ISREG(inode
->i_mode
))
1451 /* We cannot do exclusive creation on a positive dentry */
1452 if (flags
& LOOKUP_EXCL
)
1455 /* Let f_op->open() actually open (and revalidate) the file */
1465 return nfs_lookup_revalidate(dentry
, flags
);
1468 #endif /* CONFIG_NFSV4 */
1471 * Code common to create, mkdir, and mknod.
1473 int nfs_instantiate(struct dentry
*dentry
, struct nfs_fh
*fhandle
,
1474 struct nfs_fattr
*fattr
)
1476 struct dentry
*parent
= dget_parent(dentry
);
1477 struct inode
*dir
= parent
->d_inode
;
1478 struct inode
*inode
;
1479 int error
= -EACCES
;
1483 /* We may have been initialized further down */
1484 if (dentry
->d_inode
)
1486 if (fhandle
->size
== 0) {
1487 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
);
1491 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1492 if (!(fattr
->valid
& NFS_ATTR_FATTR
)) {
1493 struct nfs_server
*server
= NFS_SB(dentry
->d_sb
);
1494 error
= server
->nfs_client
->rpc_ops
->getattr(server
, fhandle
, fattr
);
1498 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
);
1499 error
= PTR_ERR(inode
);
1502 d_add(dentry
, inode
);
1507 nfs_mark_for_revalidate(dir
);
1513 * Following a failed create operation, we drop the dentry rather
1514 * than retain a negative dentry. This avoids a problem in the event
1515 * that the operation succeeded on the server, but an error in the
1516 * reply path made it appear to have failed.
1518 int nfs_create(struct inode
*dir
, struct dentry
*dentry
,
1519 umode_t mode
, bool excl
)
1522 int open_flags
= excl
? O_CREAT
| O_EXCL
: O_CREAT
;
1525 dfprintk(VFS
, "NFS: create(%s/%ld), %s\n",
1526 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1528 attr
.ia_mode
= mode
;
1529 attr
.ia_valid
= ATTR_MODE
;
1531 error
= NFS_PROTO(dir
)->create(dir
, dentry
, &attr
, open_flags
);
1541 * See comments for nfs_proc_create regarding failed operations.
1544 nfs_mknod(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
, dev_t rdev
)
1549 dfprintk(VFS
, "NFS: mknod(%s/%ld), %s\n",
1550 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1552 if (!new_valid_dev(rdev
))
1555 attr
.ia_mode
= mode
;
1556 attr
.ia_valid
= ATTR_MODE
;
1558 status
= NFS_PROTO(dir
)->mknod(dir
, dentry
, &attr
, rdev
);
1568 * See comments for nfs_proc_create regarding failed operations.
1570 int nfs_mkdir(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
)
1575 dfprintk(VFS
, "NFS: mkdir(%s/%ld), %s\n",
1576 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1578 attr
.ia_valid
= ATTR_MODE
;
1579 attr
.ia_mode
= mode
| S_IFDIR
;
1581 error
= NFS_PROTO(dir
)->mkdir(dir
, dentry
, &attr
);
1590 static void nfs_dentry_handle_enoent(struct dentry
*dentry
)
1592 if (dentry
->d_inode
!= NULL
&& !d_unhashed(dentry
))
1596 int nfs_rmdir(struct inode
*dir
, struct dentry
*dentry
)
1600 dfprintk(VFS
, "NFS: rmdir(%s/%ld), %s\n",
1601 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1603 error
= NFS_PROTO(dir
)->rmdir(dir
, &dentry
->d_name
);
1604 /* Ensure the VFS deletes this inode */
1605 if (error
== 0 && dentry
->d_inode
!= NULL
)
1606 clear_nlink(dentry
->d_inode
);
1607 else if (error
== -ENOENT
)
1608 nfs_dentry_handle_enoent(dentry
);
1614 * Remove a file after making sure there are no pending writes,
1615 * and after checking that the file has only one user.
1617 * We invalidate the attribute cache and free the inode prior to the operation
1618 * to avoid possible races if the server reuses the inode.
1620 static int nfs_safe_remove(struct dentry
*dentry
)
1622 struct inode
*dir
= dentry
->d_parent
->d_inode
;
1623 struct inode
*inode
= dentry
->d_inode
;
1626 dfprintk(VFS
, "NFS: safe_remove(%s/%s)\n",
1627 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
1629 /* If the dentry was sillyrenamed, we simply call d_delete() */
1630 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1635 if (inode
!= NULL
) {
1636 NFS_PROTO(inode
)->return_delegation(inode
);
1637 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1638 /* The VFS may want to delete this inode */
1640 nfs_drop_nlink(inode
);
1641 nfs_mark_for_revalidate(inode
);
1643 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1644 if (error
== -ENOENT
)
1645 nfs_dentry_handle_enoent(dentry
);
1650 /* We do silly rename. In case sillyrename() returns -EBUSY, the inode
1651 * belongs to an active ".nfs..." file and we return -EBUSY.
1653 * If sillyrename() returns 0, we do nothing, otherwise we unlink.
1655 int nfs_unlink(struct inode
*dir
, struct dentry
*dentry
)
1658 int need_rehash
= 0;
1660 dfprintk(VFS
, "NFS: unlink(%s/%ld, %s)\n", dir
->i_sb
->s_id
,
1661 dir
->i_ino
, dentry
->d_name
.name
);
1663 spin_lock(&dentry
->d_lock
);
1664 if (dentry
->d_count
> 1) {
1665 spin_unlock(&dentry
->d_lock
);
1666 /* Start asynchronous writeout of the inode */
1667 write_inode_now(dentry
->d_inode
, 0);
1668 error
= nfs_sillyrename(dir
, dentry
);
1671 if (!d_unhashed(dentry
)) {
1675 spin_unlock(&dentry
->d_lock
);
1676 error
= nfs_safe_remove(dentry
);
1677 if (!error
|| error
== -ENOENT
) {
1678 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1679 } else if (need_rehash
)
1685 * To create a symbolic link, most file systems instantiate a new inode,
1686 * add a page to it containing the path, then write it out to the disk
1687 * using prepare_write/commit_write.
1689 * Unfortunately the NFS client can't create the in-core inode first
1690 * because it needs a file handle to create an in-core inode (see
1691 * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the
1692 * symlink request has completed on the server.
1694 * So instead we allocate a raw page, copy the symname into it, then do
1695 * the SYMLINK request with the page as the buffer. If it succeeds, we
1696 * now have a new file handle and can instantiate an in-core NFS inode
1697 * and move the raw page into its mapping.
1699 int nfs_symlink(struct inode
*dir
, struct dentry
*dentry
, const char *symname
)
1701 struct pagevec lru_pvec
;
1705 unsigned int pathlen
= strlen(symname
);
1708 dfprintk(VFS
, "NFS: symlink(%s/%ld, %s, %s)\n", dir
->i_sb
->s_id
,
1709 dir
->i_ino
, dentry
->d_name
.name
, symname
);
1711 if (pathlen
> PAGE_SIZE
)
1712 return -ENAMETOOLONG
;
1714 attr
.ia_mode
= S_IFLNK
| S_IRWXUGO
;
1715 attr
.ia_valid
= ATTR_MODE
;
1717 page
= alloc_page(GFP_HIGHUSER
);
1721 kaddr
= kmap_atomic(page
);
1722 memcpy(kaddr
, symname
, pathlen
);
1723 if (pathlen
< PAGE_SIZE
)
1724 memset(kaddr
+ pathlen
, 0, PAGE_SIZE
- pathlen
);
1725 kunmap_atomic(kaddr
);
1727 error
= NFS_PROTO(dir
)->symlink(dir
, dentry
, page
, pathlen
, &attr
);
1729 dfprintk(VFS
, "NFS: symlink(%s/%ld, %s, %s) error %d\n",
1730 dir
->i_sb
->s_id
, dir
->i_ino
,
1731 dentry
->d_name
.name
, symname
, error
);
1738 * No big deal if we can't add this page to the page cache here.
1739 * READLINK will get the missing page from the server if needed.
1741 pagevec_init(&lru_pvec
, 0);
1742 if (!add_to_page_cache(page
, dentry
->d_inode
->i_mapping
, 0,
1744 pagevec_add(&lru_pvec
, page
);
1745 pagevec_lru_add_file(&lru_pvec
);
1746 SetPageUptodate(page
);
1755 nfs_link(struct dentry
*old_dentry
, struct inode
*dir
, struct dentry
*dentry
)
1757 struct inode
*inode
= old_dentry
->d_inode
;
1760 dfprintk(VFS
, "NFS: link(%s/%s -> %s/%s)\n",
1761 old_dentry
->d_parent
->d_name
.name
, old_dentry
->d_name
.name
,
1762 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
1764 NFS_PROTO(inode
)->return_delegation(inode
);
1767 error
= NFS_PROTO(dir
)->link(inode
, dir
, &dentry
->d_name
);
1770 d_add(dentry
, inode
);
1777 * FIXME: Some nfsds, like the Linux user space nfsd, may generate a
1778 * different file handle for the same inode after a rename (e.g. when
1779 * moving to a different directory). A fail-safe method to do so would
1780 * be to look up old_dir/old_name, create a link to new_dir/new_name and
1781 * rename the old file using the sillyrename stuff. This way, the original
1782 * file in old_dir will go away when the last process iput()s the inode.
1786 * It actually works quite well. One needs to have the possibility for
1787 * at least one ".nfs..." file in each directory the file ever gets
1788 * moved or linked to which happens automagically with the new
1789 * implementation that only depends on the dcache stuff instead of
1790 * using the inode layer
1792 * Unfortunately, things are a little more complicated than indicated
1793 * above. For a cross-directory move, we want to make sure we can get
1794 * rid of the old inode after the operation. This means there must be
1795 * no pending writes (if it's a file), and the use count must be 1.
1796 * If these conditions are met, we can drop the dentries before doing
1799 int nfs_rename(struct inode
*old_dir
, struct dentry
*old_dentry
,
1800 struct inode
*new_dir
, struct dentry
*new_dentry
)
1802 struct inode
*old_inode
= old_dentry
->d_inode
;
1803 struct inode
*new_inode
= new_dentry
->d_inode
;
1804 struct dentry
*dentry
= NULL
, *rehash
= NULL
;
1807 dfprintk(VFS
, "NFS: rename(%s/%s -> %s/%s, ct=%d)\n",
1808 old_dentry
->d_parent
->d_name
.name
, old_dentry
->d_name
.name
,
1809 new_dentry
->d_parent
->d_name
.name
, new_dentry
->d_name
.name
,
1810 new_dentry
->d_count
);
1813 * For non-directories, check whether the target is busy and if so,
1814 * make a copy of the dentry and then do a silly-rename. If the
1815 * silly-rename succeeds, the copied dentry is hashed and becomes
1818 if (new_inode
&& !S_ISDIR(new_inode
->i_mode
)) {
1820 * To prevent any new references to the target during the
1821 * rename, we unhash the dentry in advance.
1823 if (!d_unhashed(new_dentry
)) {
1825 rehash
= new_dentry
;
1828 if (new_dentry
->d_count
> 2) {
1831 /* copy the target dentry's name */
1832 dentry
= d_alloc(new_dentry
->d_parent
,
1833 &new_dentry
->d_name
);
1837 /* silly-rename the existing target ... */
1838 err
= nfs_sillyrename(new_dir
, new_dentry
);
1842 new_dentry
= dentry
;
1848 NFS_PROTO(old_inode
)->return_delegation(old_inode
);
1849 if (new_inode
!= NULL
)
1850 NFS_PROTO(new_inode
)->return_delegation(new_inode
);
1852 error
= NFS_PROTO(old_dir
)->rename(old_dir
, &old_dentry
->d_name
,
1853 new_dir
, &new_dentry
->d_name
);
1854 nfs_mark_for_revalidate(old_inode
);
1859 if (new_inode
!= NULL
)
1860 nfs_drop_nlink(new_inode
);
1861 d_move(old_dentry
, new_dentry
);
1862 nfs_set_verifier(new_dentry
,
1863 nfs_save_change_attribute(new_dir
));
1864 } else if (error
== -ENOENT
)
1865 nfs_dentry_handle_enoent(old_dentry
);
1867 /* new dentry created? */
1873 static DEFINE_SPINLOCK(nfs_access_lru_lock
);
1874 static LIST_HEAD(nfs_access_lru_list
);
1875 static atomic_long_t nfs_access_nr_entries
;
1877 static void nfs_access_free_entry(struct nfs_access_entry
*entry
)
1879 put_rpccred(entry
->cred
);
1881 smp_mb__before_atomic_dec();
1882 atomic_long_dec(&nfs_access_nr_entries
);
1883 smp_mb__after_atomic_dec();
1886 static void nfs_access_free_list(struct list_head
*head
)
1888 struct nfs_access_entry
*cache
;
1890 while (!list_empty(head
)) {
1891 cache
= list_entry(head
->next
, struct nfs_access_entry
, lru
);
1892 list_del(&cache
->lru
);
1893 nfs_access_free_entry(cache
);
1897 int nfs_access_cache_shrinker(struct shrinker
*shrink
,
1898 struct shrink_control
*sc
)
1901 struct nfs_inode
*nfsi
, *next
;
1902 struct nfs_access_entry
*cache
;
1903 int nr_to_scan
= sc
->nr_to_scan
;
1904 gfp_t gfp_mask
= sc
->gfp_mask
;
1906 if ((gfp_mask
& GFP_KERNEL
) != GFP_KERNEL
)
1907 return (nr_to_scan
== 0) ? 0 : -1;
1909 spin_lock(&nfs_access_lru_lock
);
1910 list_for_each_entry_safe(nfsi
, next
, &nfs_access_lru_list
, access_cache_inode_lru
) {
1911 struct inode
*inode
;
1913 if (nr_to_scan
-- == 0)
1915 inode
= &nfsi
->vfs_inode
;
1916 spin_lock(&inode
->i_lock
);
1917 if (list_empty(&nfsi
->access_cache_entry_lru
))
1918 goto remove_lru_entry
;
1919 cache
= list_entry(nfsi
->access_cache_entry_lru
.next
,
1920 struct nfs_access_entry
, lru
);
1921 list_move(&cache
->lru
, &head
);
1922 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
1923 if (!list_empty(&nfsi
->access_cache_entry_lru
))
1924 list_move_tail(&nfsi
->access_cache_inode_lru
,
1925 &nfs_access_lru_list
);
1928 list_del_init(&nfsi
->access_cache_inode_lru
);
1929 smp_mb__before_clear_bit();
1930 clear_bit(NFS_INO_ACL_LRU_SET
, &nfsi
->flags
);
1931 smp_mb__after_clear_bit();
1933 spin_unlock(&inode
->i_lock
);
1935 spin_unlock(&nfs_access_lru_lock
);
1936 nfs_access_free_list(&head
);
1937 return (atomic_long_read(&nfs_access_nr_entries
) / 100) * sysctl_vfs_cache_pressure
;
1940 static void __nfs_access_zap_cache(struct nfs_inode
*nfsi
, struct list_head
*head
)
1942 struct rb_root
*root_node
= &nfsi
->access_cache
;
1944 struct nfs_access_entry
*entry
;
1946 /* Unhook entries from the cache */
1947 while ((n
= rb_first(root_node
)) != NULL
) {
1948 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
1949 rb_erase(n
, root_node
);
1950 list_move(&entry
->lru
, head
);
1952 nfsi
->cache_validity
&= ~NFS_INO_INVALID_ACCESS
;
1955 void nfs_access_zap_cache(struct inode
*inode
)
1959 if (test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
) == 0)
1961 /* Remove from global LRU init */
1962 spin_lock(&nfs_access_lru_lock
);
1963 if (test_and_clear_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
1964 list_del_init(&NFS_I(inode
)->access_cache_inode_lru
);
1966 spin_lock(&inode
->i_lock
);
1967 __nfs_access_zap_cache(NFS_I(inode
), &head
);
1968 spin_unlock(&inode
->i_lock
);
1969 spin_unlock(&nfs_access_lru_lock
);
1970 nfs_access_free_list(&head
);
1973 static struct nfs_access_entry
*nfs_access_search_rbtree(struct inode
*inode
, struct rpc_cred
*cred
)
1975 struct rb_node
*n
= NFS_I(inode
)->access_cache
.rb_node
;
1976 struct nfs_access_entry
*entry
;
1979 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
1981 if (cred
< entry
->cred
)
1983 else if (cred
> entry
->cred
)
1991 static int nfs_access_get_cached(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_access_entry
*res
)
1993 struct nfs_inode
*nfsi
= NFS_I(inode
);
1994 struct nfs_access_entry
*cache
;
1997 spin_lock(&inode
->i_lock
);
1998 if (nfsi
->cache_validity
& NFS_INO_INVALID_ACCESS
)
2000 cache
= nfs_access_search_rbtree(inode
, cred
);
2003 if (!nfs_have_delegated_attributes(inode
) &&
2004 !time_in_range_open(jiffies
, cache
->jiffies
, cache
->jiffies
+ nfsi
->attrtimeo
))
2006 res
->jiffies
= cache
->jiffies
;
2007 res
->cred
= cache
->cred
;
2008 res
->mask
= cache
->mask
;
2009 list_move_tail(&cache
->lru
, &nfsi
->access_cache_entry_lru
);
2012 spin_unlock(&inode
->i_lock
);
2015 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
2016 list_del(&cache
->lru
);
2017 spin_unlock(&inode
->i_lock
);
2018 nfs_access_free_entry(cache
);
2021 spin_unlock(&inode
->i_lock
);
2022 nfs_access_zap_cache(inode
);
2026 static void nfs_access_add_rbtree(struct inode
*inode
, struct nfs_access_entry
*set
)
2028 struct nfs_inode
*nfsi
= NFS_I(inode
);
2029 struct rb_root
*root_node
= &nfsi
->access_cache
;
2030 struct rb_node
**p
= &root_node
->rb_node
;
2031 struct rb_node
*parent
= NULL
;
2032 struct nfs_access_entry
*entry
;
2034 spin_lock(&inode
->i_lock
);
2035 while (*p
!= NULL
) {
2037 entry
= rb_entry(parent
, struct nfs_access_entry
, rb_node
);
2039 if (set
->cred
< entry
->cred
)
2040 p
= &parent
->rb_left
;
2041 else if (set
->cred
> entry
->cred
)
2042 p
= &parent
->rb_right
;
2046 rb_link_node(&set
->rb_node
, parent
, p
);
2047 rb_insert_color(&set
->rb_node
, root_node
);
2048 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2049 spin_unlock(&inode
->i_lock
);
2052 rb_replace_node(parent
, &set
->rb_node
, root_node
);
2053 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2054 list_del(&entry
->lru
);
2055 spin_unlock(&inode
->i_lock
);
2056 nfs_access_free_entry(entry
);
2059 static void nfs_access_add_cache(struct inode
*inode
, struct nfs_access_entry
*set
)
2061 struct nfs_access_entry
*cache
= kmalloc(sizeof(*cache
), GFP_KERNEL
);
2064 RB_CLEAR_NODE(&cache
->rb_node
);
2065 cache
->jiffies
= set
->jiffies
;
2066 cache
->cred
= get_rpccred(set
->cred
);
2067 cache
->mask
= set
->mask
;
2069 nfs_access_add_rbtree(inode
, cache
);
2071 /* Update accounting */
2072 smp_mb__before_atomic_inc();
2073 atomic_long_inc(&nfs_access_nr_entries
);
2074 smp_mb__after_atomic_inc();
2076 /* Add inode to global LRU list */
2077 if (!test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
)) {
2078 spin_lock(&nfs_access_lru_lock
);
2079 if (!test_and_set_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
2080 list_add_tail(&NFS_I(inode
)->access_cache_inode_lru
,
2081 &nfs_access_lru_list
);
2082 spin_unlock(&nfs_access_lru_lock
);
2086 static int nfs_do_access(struct inode
*inode
, struct rpc_cred
*cred
, int mask
)
2088 struct nfs_access_entry cache
;
2091 status
= nfs_access_get_cached(inode
, cred
, &cache
);
2095 /* Be clever: ask server to check for all possible rights */
2096 cache
.mask
= MAY_EXEC
| MAY_WRITE
| MAY_READ
;
2098 cache
.jiffies
= jiffies
;
2099 status
= NFS_PROTO(inode
)->access(inode
, &cache
);
2101 if (status
== -ESTALE
) {
2102 nfs_zap_caches(inode
);
2103 if (!S_ISDIR(inode
->i_mode
))
2104 set_bit(NFS_INO_STALE
, &NFS_I(inode
)->flags
);
2108 nfs_access_add_cache(inode
, &cache
);
2110 if ((mask
& ~cache
.mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) == 0)
2115 static int nfs_open_permission_mask(int openflags
)
2119 if ((openflags
& O_ACCMODE
) != O_WRONLY
)
2121 if ((openflags
& O_ACCMODE
) != O_RDONLY
)
2123 if (openflags
& __FMODE_EXEC
)
2128 int nfs_may_open(struct inode
*inode
, struct rpc_cred
*cred
, int openflags
)
2130 return nfs_do_access(inode
, cred
, nfs_open_permission_mask(openflags
));
2133 int nfs_permission(struct inode
*inode
, int mask
)
2135 struct rpc_cred
*cred
;
2138 if (mask
& MAY_NOT_BLOCK
)
2141 nfs_inc_stats(inode
, NFSIOS_VFSACCESS
);
2143 if ((mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) == 0)
2145 /* Is this sys_access() ? */
2146 if (mask
& (MAY_ACCESS
| MAY_CHDIR
))
2149 switch (inode
->i_mode
& S_IFMT
) {
2153 /* NFSv4 has atomic_open... */
2154 if (nfs_server_capable(inode
, NFS_CAP_ATOMIC_OPEN
)
2155 && (mask
& MAY_OPEN
)
2156 && !(mask
& MAY_EXEC
))
2161 * Optimize away all write operations, since the server
2162 * will check permissions when we perform the op.
2164 if ((mask
& MAY_WRITE
) && !(mask
& MAY_READ
))
2169 if (!NFS_PROTO(inode
)->access
)
2172 cred
= rpc_lookup_cred();
2173 if (!IS_ERR(cred
)) {
2174 res
= nfs_do_access(inode
, cred
, mask
);
2177 res
= PTR_ERR(cred
);
2179 if (!res
&& (mask
& MAY_EXEC
) && !execute_ok(inode
))
2182 dfprintk(VFS
, "NFS: permission(%s/%ld), mask=0x%x, res=%d\n",
2183 inode
->i_sb
->s_id
, inode
->i_ino
, mask
, res
);
2186 res
= nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
2188 res
= generic_permission(inode
, mask
);
2194 * version-control: t
2195 * kept-new-versions: 5