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"
46 /* #define NFS_DEBUG_VERBOSE 1 */
48 static int nfs_opendir(struct inode
*, struct file
*);
49 static int nfs_closedir(struct inode
*, struct file
*);
50 static int nfs_readdir(struct file
*, struct dir_context
*);
51 static int nfs_fsync_dir(struct file
*, loff_t
, loff_t
, int);
52 static loff_t
nfs_llseek_dir(struct file
*, loff_t
, int);
53 static void nfs_readdir_clear_array(struct page
*);
55 const struct file_operations nfs_dir_operations
= {
56 .llseek
= nfs_llseek_dir
,
57 .read
= generic_read_dir
,
58 .iterate
= nfs_readdir
,
60 .release
= nfs_closedir
,
61 .fsync
= nfs_fsync_dir
,
64 const struct address_space_operations nfs_dir_aops
= {
65 .freepage
= nfs_readdir_clear_array
,
68 static struct nfs_open_dir_context
*alloc_nfs_open_dir_context(struct inode
*dir
, struct rpc_cred
*cred
)
70 struct nfs_open_dir_context
*ctx
;
71 ctx
= kmalloc(sizeof(*ctx
), GFP_KERNEL
);
74 ctx
->attr_gencount
= NFS_I(dir
)->attr_gencount
;
77 ctx
->cred
= get_rpccred(cred
);
80 return ERR_PTR(-ENOMEM
);
83 static void put_nfs_open_dir_context(struct nfs_open_dir_context
*ctx
)
85 put_rpccred(ctx
->cred
);
93 nfs_opendir(struct inode
*inode
, struct file
*filp
)
96 struct nfs_open_dir_context
*ctx
;
97 struct rpc_cred
*cred
;
99 dfprintk(FILE, "NFS: open dir(%s/%s)\n",
100 filp
->f_path
.dentry
->d_parent
->d_name
.name
,
101 filp
->f_path
.dentry
->d_name
.name
);
103 nfs_inc_stats(inode
, NFSIOS_VFSOPEN
);
105 cred
= rpc_lookup_cred();
107 return PTR_ERR(cred
);
108 ctx
= alloc_nfs_open_dir_context(inode
, cred
);
113 filp
->private_data
= ctx
;
114 if (filp
->f_path
.dentry
== filp
->f_path
.mnt
->mnt_root
) {
115 /* This is a mountpoint, so d_revalidate will never
116 * have been called, so we need to refresh the
117 * inode (for close-open consistency) ourselves.
119 __nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
127 nfs_closedir(struct inode
*inode
, struct file
*filp
)
129 put_nfs_open_dir_context(filp
->private_data
);
133 struct nfs_cache_array_entry
{
137 unsigned char d_type
;
140 struct nfs_cache_array
{
144 struct nfs_cache_array_entry array
[0];
147 typedef int (*decode_dirent_t
)(struct xdr_stream
*, struct nfs_entry
*, int);
151 struct dir_context
*ctx
;
152 unsigned long page_index
;
155 loff_t current_index
;
156 decode_dirent_t decode
;
158 unsigned long timestamp
;
159 unsigned long gencount
;
160 unsigned int cache_entry_index
;
163 } nfs_readdir_descriptor_t
;
166 * The caller is responsible for calling nfs_readdir_release_array(page)
169 struct nfs_cache_array
*nfs_readdir_get_array(struct page
*page
)
173 return ERR_PTR(-EIO
);
176 return ERR_PTR(-ENOMEM
);
181 void nfs_readdir_release_array(struct page
*page
)
187 * we are freeing strings created by nfs_add_to_readdir_array()
190 void nfs_readdir_clear_array(struct page
*page
)
192 struct nfs_cache_array
*array
;
195 array
= kmap_atomic(page
);
196 for (i
= 0; i
< array
->size
; i
++)
197 kfree(array
->array
[i
].string
.name
);
198 kunmap_atomic(array
);
202 * the caller is responsible for freeing qstr.name
203 * when called by nfs_readdir_add_to_array, the strings will be freed in
204 * nfs_clear_readdir_array()
207 int nfs_readdir_make_qstr(struct qstr
*string
, const char *name
, unsigned int len
)
210 string
->name
= kmemdup(name
, len
, GFP_KERNEL
);
211 if (string
->name
== NULL
)
214 * Avoid a kmemleak false positive. The pointer to the name is stored
215 * in a page cache page which kmemleak does not scan.
217 kmemleak_not_leak(string
->name
);
218 string
->hash
= full_name_hash(name
, len
);
223 int nfs_readdir_add_to_array(struct nfs_entry
*entry
, struct page
*page
)
225 struct nfs_cache_array
*array
= nfs_readdir_get_array(page
);
226 struct nfs_cache_array_entry
*cache_entry
;
230 return PTR_ERR(array
);
232 cache_entry
= &array
->array
[array
->size
];
234 /* Check that this entry lies within the page bounds */
236 if ((char *)&cache_entry
[1] - (char *)page_address(page
) > PAGE_SIZE
)
239 cache_entry
->cookie
= entry
->prev_cookie
;
240 cache_entry
->ino
= entry
->ino
;
241 cache_entry
->d_type
= entry
->d_type
;
242 ret
= nfs_readdir_make_qstr(&cache_entry
->string
, entry
->name
, entry
->len
);
245 array
->last_cookie
= entry
->cookie
;
248 array
->eof_index
= array
->size
;
250 nfs_readdir_release_array(page
);
255 int nfs_readdir_search_for_pos(struct nfs_cache_array
*array
, nfs_readdir_descriptor_t
*desc
)
257 loff_t diff
= desc
->ctx
->pos
- desc
->current_index
;
262 if (diff
>= array
->size
) {
263 if (array
->eof_index
>= 0)
268 index
= (unsigned int)diff
;
269 *desc
->dir_cookie
= array
->array
[index
].cookie
;
270 desc
->cache_entry_index
= index
;
278 int nfs_readdir_search_for_cookie(struct nfs_cache_array
*array
, nfs_readdir_descriptor_t
*desc
)
282 int status
= -EAGAIN
;
284 for (i
= 0; i
< array
->size
; i
++) {
285 if (array
->array
[i
].cookie
== *desc
->dir_cookie
) {
286 struct nfs_inode
*nfsi
= NFS_I(file_inode(desc
->file
));
287 struct nfs_open_dir_context
*ctx
= desc
->file
->private_data
;
289 new_pos
= desc
->current_index
+ i
;
290 if (ctx
->attr_gencount
!= nfsi
->attr_gencount
291 || (nfsi
->cache_validity
& (NFS_INO_INVALID_ATTR
|NFS_INO_INVALID_DATA
))) {
293 ctx
->attr_gencount
= nfsi
->attr_gencount
;
294 } else if (new_pos
< desc
->ctx
->pos
) {
296 && ctx
->dup_cookie
== *desc
->dir_cookie
) {
297 if (printk_ratelimit()) {
298 pr_notice("NFS: directory %s/%s contains a readdir loop."
299 "Please contact your server vendor. "
300 "The file: %s has duplicate cookie %llu\n",
301 desc
->file
->f_dentry
->d_parent
->d_name
.name
,
302 desc
->file
->f_dentry
->d_name
.name
,
303 array
->array
[i
].string
.name
,
309 ctx
->dup_cookie
= *desc
->dir_cookie
;
312 desc
->ctx
->pos
= new_pos
;
313 desc
->cache_entry_index
= i
;
317 if (array
->eof_index
>= 0) {
318 status
= -EBADCOOKIE
;
319 if (*desc
->dir_cookie
== array
->last_cookie
)
327 int nfs_readdir_search_array(nfs_readdir_descriptor_t
*desc
)
329 struct nfs_cache_array
*array
;
332 array
= nfs_readdir_get_array(desc
->page
);
334 status
= PTR_ERR(array
);
338 if (*desc
->dir_cookie
== 0)
339 status
= nfs_readdir_search_for_pos(array
, desc
);
341 status
= nfs_readdir_search_for_cookie(array
, desc
);
343 if (status
== -EAGAIN
) {
344 desc
->last_cookie
= array
->last_cookie
;
345 desc
->current_index
+= array
->size
;
348 nfs_readdir_release_array(desc
->page
);
353 /* Fill a page with xdr information before transferring to the cache page */
355 int nfs_readdir_xdr_filler(struct page
**pages
, nfs_readdir_descriptor_t
*desc
,
356 struct nfs_entry
*entry
, struct file
*file
, struct inode
*inode
)
358 struct nfs_open_dir_context
*ctx
= file
->private_data
;
359 struct rpc_cred
*cred
= ctx
->cred
;
360 unsigned long timestamp
, gencount
;
365 gencount
= nfs_inc_attr_generation_counter();
366 error
= NFS_PROTO(inode
)->readdir(file
->f_path
.dentry
, cred
, entry
->cookie
, pages
,
367 NFS_SERVER(inode
)->dtsize
, desc
->plus
);
369 /* We requested READDIRPLUS, but the server doesn't grok it */
370 if (error
== -ENOTSUPP
&& desc
->plus
) {
371 NFS_SERVER(inode
)->caps
&= ~NFS_CAP_READDIRPLUS
;
372 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
378 desc
->timestamp
= timestamp
;
379 desc
->gencount
= gencount
;
384 static int xdr_decode(nfs_readdir_descriptor_t
*desc
,
385 struct nfs_entry
*entry
, struct xdr_stream
*xdr
)
389 error
= desc
->decode(xdr
, entry
, desc
->plus
);
392 entry
->fattr
->time_start
= desc
->timestamp
;
393 entry
->fattr
->gencount
= desc
->gencount
;
398 int nfs_same_file(struct dentry
*dentry
, struct nfs_entry
*entry
)
400 if (dentry
->d_inode
== NULL
)
402 if (nfs_compare_fh(entry
->fh
, NFS_FH(dentry
->d_inode
)) != 0)
410 bool nfs_use_readdirplus(struct inode
*dir
, struct dir_context
*ctx
)
412 if (!nfs_server_capable(dir
, NFS_CAP_READDIRPLUS
))
414 if (test_and_clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(dir
)->flags
))
422 * This function is called by the lookup code to request the use of
423 * readdirplus to accelerate any future lookups in the same
427 void nfs_advise_use_readdirplus(struct inode
*dir
)
429 set_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(dir
)->flags
);
433 void nfs_prime_dcache(struct dentry
*parent
, struct nfs_entry
*entry
)
435 struct qstr filename
= QSTR_INIT(entry
->name
, entry
->len
);
436 struct dentry
*dentry
;
437 struct dentry
*alias
;
438 struct inode
*dir
= parent
->d_inode
;
441 if (filename
.name
[0] == '.') {
442 if (filename
.len
== 1)
444 if (filename
.len
== 2 && filename
.name
[1] == '.')
447 filename
.hash
= full_name_hash(filename
.name
, filename
.len
);
449 dentry
= d_lookup(parent
, &filename
);
450 if (dentry
!= NULL
) {
451 if (nfs_same_file(dentry
, entry
)) {
452 nfs_refresh_inode(dentry
->d_inode
, entry
->fattr
);
455 if (d_invalidate(dentry
) != 0)
461 dentry
= d_alloc(parent
, &filename
);
465 inode
= nfs_fhget(dentry
->d_sb
, entry
->fh
, entry
->fattr
);
469 alias
= d_materialise_unique(dentry
, inode
);
473 nfs_set_verifier(alias
, nfs_save_change_attribute(dir
));
476 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
482 /* Perform conversion from xdr to cache array */
484 int nfs_readdir_page_filler(nfs_readdir_descriptor_t
*desc
, struct nfs_entry
*entry
,
485 struct page
**xdr_pages
, struct page
*page
, unsigned int buflen
)
487 struct xdr_stream stream
;
489 struct page
*scratch
;
490 struct nfs_cache_array
*array
;
491 unsigned int count
= 0;
494 scratch
= alloc_page(GFP_KERNEL
);
498 xdr_init_decode_pages(&stream
, &buf
, xdr_pages
, buflen
);
499 xdr_set_scratch_buffer(&stream
, page_address(scratch
), PAGE_SIZE
);
502 status
= xdr_decode(desc
, entry
, &stream
);
504 if (status
== -EAGAIN
)
512 nfs_prime_dcache(desc
->file
->f_path
.dentry
, entry
);
514 status
= nfs_readdir_add_to_array(entry
, page
);
517 } while (!entry
->eof
);
519 if (count
== 0 || (status
== -EBADCOOKIE
&& entry
->eof
!= 0)) {
520 array
= nfs_readdir_get_array(page
);
521 if (!IS_ERR(array
)) {
522 array
->eof_index
= array
->size
;
524 nfs_readdir_release_array(page
);
526 status
= PTR_ERR(array
);
534 void nfs_readdir_free_pagearray(struct page
**pages
, unsigned int npages
)
537 for (i
= 0; i
< npages
; i
++)
542 void nfs_readdir_free_large_page(void *ptr
, struct page
**pages
,
545 nfs_readdir_free_pagearray(pages
, npages
);
549 * nfs_readdir_large_page will allocate pages that must be freed with a call
550 * to nfs_readdir_free_large_page
553 int nfs_readdir_large_page(struct page
**pages
, unsigned int npages
)
557 for (i
= 0; i
< npages
; i
++) {
558 struct page
*page
= alloc_page(GFP_KERNEL
);
566 nfs_readdir_free_pagearray(pages
, i
);
571 int nfs_readdir_xdr_to_array(nfs_readdir_descriptor_t
*desc
, struct page
*page
, struct inode
*inode
)
573 struct page
*pages
[NFS_MAX_READDIR_PAGES
];
574 void *pages_ptr
= NULL
;
575 struct nfs_entry entry
;
576 struct file
*file
= desc
->file
;
577 struct nfs_cache_array
*array
;
578 int status
= -ENOMEM
;
579 unsigned int array_size
= ARRAY_SIZE(pages
);
581 entry
.prev_cookie
= 0;
582 entry
.cookie
= desc
->last_cookie
;
584 entry
.fh
= nfs_alloc_fhandle();
585 entry
.fattr
= nfs_alloc_fattr();
586 entry
.server
= NFS_SERVER(inode
);
587 if (entry
.fh
== NULL
|| entry
.fattr
== NULL
)
590 array
= nfs_readdir_get_array(page
);
592 status
= PTR_ERR(array
);
595 memset(array
, 0, sizeof(struct nfs_cache_array
));
596 array
->eof_index
= -1;
598 status
= nfs_readdir_large_page(pages
, array_size
);
600 goto out_release_array
;
603 status
= nfs_readdir_xdr_filler(pages
, desc
, &entry
, file
, inode
);
608 status
= nfs_readdir_page_filler(desc
, &entry
, pages
, page
, pglen
);
610 if (status
== -ENOSPC
)
614 } while (array
->eof_index
< 0);
616 nfs_readdir_free_large_page(pages_ptr
, pages
, array_size
);
618 nfs_readdir_release_array(page
);
620 nfs_free_fattr(entry
.fattr
);
621 nfs_free_fhandle(entry
.fh
);
626 * Now we cache directories properly, by converting xdr information
627 * to an array that can be used for lookups later. This results in
628 * fewer cache pages, since we can store more information on each page.
629 * We only need to convert from xdr once so future lookups are much simpler
632 int nfs_readdir_filler(nfs_readdir_descriptor_t
*desc
, struct page
* page
)
634 struct inode
*inode
= file_inode(desc
->file
);
637 ret
= nfs_readdir_xdr_to_array(desc
, page
, inode
);
640 SetPageUptodate(page
);
642 if (invalidate_inode_pages2_range(inode
->i_mapping
, page
->index
+ 1, -1) < 0) {
643 /* Should never happen */
644 nfs_zap_mapping(inode
, inode
->i_mapping
);
654 void cache_page_release(nfs_readdir_descriptor_t
*desc
)
656 if (!desc
->page
->mapping
)
657 nfs_readdir_clear_array(desc
->page
);
658 page_cache_release(desc
->page
);
663 struct page
*get_cache_page(nfs_readdir_descriptor_t
*desc
)
665 return read_cache_page(file_inode(desc
->file
)->i_mapping
,
666 desc
->page_index
, (filler_t
*)nfs_readdir_filler
, desc
);
670 * Returns 0 if desc->dir_cookie was found on page desc->page_index
673 int find_cache_page(nfs_readdir_descriptor_t
*desc
)
677 desc
->page
= get_cache_page(desc
);
678 if (IS_ERR(desc
->page
))
679 return PTR_ERR(desc
->page
);
681 res
= nfs_readdir_search_array(desc
);
683 cache_page_release(desc
);
687 /* Search for desc->dir_cookie from the beginning of the page cache */
689 int readdir_search_pagecache(nfs_readdir_descriptor_t
*desc
)
693 if (desc
->page_index
== 0) {
694 desc
->current_index
= 0;
695 desc
->last_cookie
= 0;
698 res
= find_cache_page(desc
);
699 } while (res
== -EAGAIN
);
704 * Once we've found the start of the dirent within a page: fill 'er up...
707 int nfs_do_filldir(nfs_readdir_descriptor_t
*desc
)
709 struct file
*file
= desc
->file
;
712 struct nfs_cache_array
*array
= NULL
;
713 struct nfs_open_dir_context
*ctx
= file
->private_data
;
715 array
= nfs_readdir_get_array(desc
->page
);
717 res
= PTR_ERR(array
);
721 for (i
= desc
->cache_entry_index
; i
< array
->size
; i
++) {
722 struct nfs_cache_array_entry
*ent
;
724 ent
= &array
->array
[i
];
725 if (!dir_emit(desc
->ctx
, ent
->string
.name
, ent
->string
.len
,
726 nfs_compat_user_ino64(ent
->ino
), ent
->d_type
)) {
731 if (i
< (array
->size
-1))
732 *desc
->dir_cookie
= array
->array
[i
+1].cookie
;
734 *desc
->dir_cookie
= array
->last_cookie
;
738 if (array
->eof_index
>= 0)
741 nfs_readdir_release_array(desc
->page
);
743 cache_page_release(desc
);
744 dfprintk(DIRCACHE
, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n",
745 (unsigned long long)*desc
->dir_cookie
, res
);
750 * If we cannot find a cookie in our cache, we suspect that this is
751 * because it points to a deleted file, so we ask the server to return
752 * whatever it thinks is the next entry. We then feed this to filldir.
753 * If all goes well, we should then be able to find our way round the
754 * cache on the next call to readdir_search_pagecache();
756 * NOTE: we cannot add the anonymous page to the pagecache because
757 * the data it contains might not be page aligned. Besides,
758 * we should already have a complete representation of the
759 * directory in the page cache by the time we get here.
762 int uncached_readdir(nfs_readdir_descriptor_t
*desc
)
764 struct page
*page
= NULL
;
766 struct inode
*inode
= file_inode(desc
->file
);
767 struct nfs_open_dir_context
*ctx
= desc
->file
->private_data
;
769 dfprintk(DIRCACHE
, "NFS: uncached_readdir() searching for cookie %Lu\n",
770 (unsigned long long)*desc
->dir_cookie
);
772 page
= alloc_page(GFP_HIGHUSER
);
778 desc
->page_index
= 0;
779 desc
->last_cookie
= *desc
->dir_cookie
;
783 status
= nfs_readdir_xdr_to_array(desc
, page
, inode
);
787 status
= nfs_do_filldir(desc
);
790 dfprintk(DIRCACHE
, "NFS: %s: returns %d\n",
794 cache_page_release(desc
);
798 /* The file offset position represents the dirent entry number. A
799 last cookie cache takes care of the common case of reading the
802 static int nfs_readdir(struct file
*file
, struct dir_context
*ctx
)
804 struct dentry
*dentry
= file
->f_path
.dentry
;
805 struct inode
*inode
= dentry
->d_inode
;
806 nfs_readdir_descriptor_t my_desc
,
808 struct nfs_open_dir_context
*dir_ctx
= file
->private_data
;
811 dfprintk(FILE, "NFS: readdir(%s/%s) starting at cookie %llu\n",
812 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
813 (long long)ctx
->pos
);
814 nfs_inc_stats(inode
, NFSIOS_VFSGETDENTS
);
817 * ctx->pos points to the dirent entry number.
818 * *desc->dir_cookie has the cookie for the next entry. We have
819 * to either find the entry with the appropriate number or
820 * revalidate the cookie.
822 memset(desc
, 0, sizeof(*desc
));
826 desc
->dir_cookie
= &dir_ctx
->dir_cookie
;
827 desc
->decode
= NFS_PROTO(inode
)->decode_dirent
;
828 desc
->plus
= nfs_use_readdirplus(inode
, ctx
) ? 1 : 0;
830 nfs_block_sillyrename(dentry
);
831 res
= nfs_revalidate_mapping(inode
, file
->f_mapping
);
836 res
= readdir_search_pagecache(desc
);
838 if (res
== -EBADCOOKIE
) {
840 /* This means either end of directory */
841 if (*desc
->dir_cookie
&& desc
->eof
== 0) {
842 /* Or that the server has 'lost' a cookie */
843 res
= uncached_readdir(desc
);
849 if (res
== -ETOOSMALL
&& desc
->plus
) {
850 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
851 nfs_zap_caches(inode
);
852 desc
->page_index
= 0;
860 res
= nfs_do_filldir(desc
);
863 } while (!desc
->eof
);
865 nfs_unblock_sillyrename(dentry
);
868 dfprintk(FILE, "NFS: readdir(%s/%s) returns %d\n",
869 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
874 static loff_t
nfs_llseek_dir(struct file
*filp
, loff_t offset
, int whence
)
876 struct dentry
*dentry
= filp
->f_path
.dentry
;
877 struct inode
*inode
= dentry
->d_inode
;
878 struct nfs_open_dir_context
*dir_ctx
= filp
->private_data
;
880 dfprintk(FILE, "NFS: llseek dir(%s/%s, %lld, %d)\n",
881 dentry
->d_parent
->d_name
.name
,
885 mutex_lock(&inode
->i_mutex
);
888 offset
+= filp
->f_pos
;
896 if (offset
!= filp
->f_pos
) {
897 filp
->f_pos
= offset
;
898 dir_ctx
->dir_cookie
= 0;
902 mutex_unlock(&inode
->i_mutex
);
907 * All directory operations under NFS are synchronous, so fsync()
908 * is a dummy operation.
910 static int nfs_fsync_dir(struct file
*filp
, loff_t start
, loff_t end
,
913 struct dentry
*dentry
= filp
->f_path
.dentry
;
914 struct inode
*inode
= dentry
->d_inode
;
916 dfprintk(FILE, "NFS: fsync dir(%s/%s) datasync %d\n",
917 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
920 mutex_lock(&inode
->i_mutex
);
921 nfs_inc_stats(dentry
->d_inode
, NFSIOS_VFSFSYNC
);
922 mutex_unlock(&inode
->i_mutex
);
927 * nfs_force_lookup_revalidate - Mark the directory as having changed
928 * @dir - pointer to directory inode
930 * This forces the revalidation code in nfs_lookup_revalidate() to do a
931 * full lookup on all child dentries of 'dir' whenever a change occurs
932 * on the server that might have invalidated our dcache.
934 * The caller should be holding dir->i_lock
936 void nfs_force_lookup_revalidate(struct inode
*dir
)
938 NFS_I(dir
)->cache_change_attribute
++;
940 EXPORT_SYMBOL_GPL(nfs_force_lookup_revalidate
);
943 * A check for whether or not the parent directory has changed.
944 * In the case it has, we assume that the dentries are untrustworthy
945 * and may need to be looked up again.
947 static int nfs_check_verifier(struct inode
*dir
, struct dentry
*dentry
)
951 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONE
)
953 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
955 /* Revalidate nfsi->cache_change_attribute before we declare a match */
956 if (nfs_revalidate_inode(NFS_SERVER(dir
), dir
) < 0)
958 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
964 * Use intent information to check whether or not we're going to do
965 * an O_EXCL create using this path component.
967 static int nfs_is_exclusive_create(struct inode
*dir
, unsigned int flags
)
969 if (NFS_PROTO(dir
)->version
== 2)
971 return flags
& LOOKUP_EXCL
;
975 * Inode and filehandle revalidation for lookups.
977 * We force revalidation in the cases where the VFS sets LOOKUP_REVAL,
978 * or if the intent information indicates that we're about to open this
979 * particular file and the "nocto" mount flag is not set.
983 int nfs_lookup_verify_inode(struct inode
*inode
, unsigned int flags
)
985 struct nfs_server
*server
= NFS_SERVER(inode
);
988 if (IS_AUTOMOUNT(inode
))
990 /* VFS wants an on-the-wire revalidation */
991 if (flags
& LOOKUP_REVAL
)
993 /* This is an open(2) */
994 if ((flags
& LOOKUP_OPEN
) && !(server
->flags
& NFS_MOUNT_NOCTO
) &&
995 (S_ISREG(inode
->i_mode
) || S_ISDIR(inode
->i_mode
)))
998 return (inode
->i_nlink
== 0) ? -ENOENT
: 0;
1000 ret
= __nfs_revalidate_inode(server
, inode
);
1007 * We judge how long we want to trust negative
1008 * dentries by looking at the parent inode mtime.
1010 * If parent mtime has changed, we revalidate, else we wait for a
1011 * period corresponding to the parent's attribute cache timeout value.
1014 int nfs_neg_need_reval(struct inode
*dir
, struct dentry
*dentry
,
1017 /* Don't revalidate a negative dentry if we're creating a new file */
1018 if (flags
& LOOKUP_CREATE
)
1020 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONEG
)
1022 return !nfs_check_verifier(dir
, dentry
);
1026 * This is called every time the dcache has a lookup hit,
1027 * and we should check whether we can really trust that
1030 * NOTE! The hit can be a negative hit too, don't assume
1033 * If the parent directory is seen to have changed, we throw out the
1034 * cached dentry and do a new lookup.
1036 static int nfs_lookup_revalidate(struct dentry
*dentry
, unsigned int flags
)
1039 struct inode
*inode
;
1040 struct dentry
*parent
;
1041 struct nfs_fh
*fhandle
= NULL
;
1042 struct nfs_fattr
*fattr
= NULL
;
1045 if (flags
& LOOKUP_RCU
)
1048 parent
= dget_parent(dentry
);
1049 dir
= parent
->d_inode
;
1050 nfs_inc_stats(dir
, NFSIOS_DENTRYREVALIDATE
);
1051 inode
= dentry
->d_inode
;
1054 if (nfs_neg_need_reval(dir
, dentry
, flags
))
1056 goto out_valid_noent
;
1059 if (is_bad_inode(inode
)) {
1060 dfprintk(LOOKUPCACHE
, "%s: %s/%s has dud inode\n",
1061 __func__
, dentry
->d_parent
->d_name
.name
,
1062 dentry
->d_name
.name
);
1066 if (NFS_PROTO(dir
)->have_delegation(inode
, FMODE_READ
))
1067 goto out_set_verifier
;
1069 /* Force a full look up iff the parent directory has changed */
1070 if (!nfs_is_exclusive_create(dir
, flags
) && nfs_check_verifier(dir
, dentry
)) {
1071 if (nfs_lookup_verify_inode(inode
, flags
))
1072 goto out_zap_parent
;
1076 if (NFS_STALE(inode
))
1080 fhandle
= nfs_alloc_fhandle();
1081 fattr
= nfs_alloc_fattr();
1082 if (fhandle
== NULL
|| fattr
== NULL
)
1085 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
);
1088 if (nfs_compare_fh(NFS_FH(inode
), fhandle
))
1090 if ((error
= nfs_refresh_inode(inode
, fattr
)) != 0)
1093 nfs_free_fattr(fattr
);
1094 nfs_free_fhandle(fhandle
);
1096 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1098 /* Success: notify readdir to use READDIRPLUS */
1099 nfs_advise_use_readdirplus(dir
);
1102 dfprintk(LOOKUPCACHE
, "NFS: %s(%s/%s) is valid\n",
1103 __func__
, dentry
->d_parent
->d_name
.name
,
1104 dentry
->d_name
.name
);
1107 nfs_zap_caches(dir
);
1109 nfs_free_fattr(fattr
);
1110 nfs_free_fhandle(fhandle
);
1111 nfs_mark_for_revalidate(dir
);
1112 if (inode
&& S_ISDIR(inode
->i_mode
)) {
1113 /* Purge readdir caches. */
1114 nfs_zap_caches(inode
);
1115 /* If we have submounts, don't unhash ! */
1116 if (have_submounts(dentry
))
1118 if (dentry
->d_flags
& DCACHE_DISCONNECTED
)
1120 shrink_dcache_parent(dentry
);
1124 dfprintk(LOOKUPCACHE
, "NFS: %s(%s/%s) is invalid\n",
1125 __func__
, dentry
->d_parent
->d_name
.name
,
1126 dentry
->d_name
.name
);
1129 nfs_free_fattr(fattr
);
1130 nfs_free_fhandle(fhandle
);
1132 dfprintk(LOOKUPCACHE
, "NFS: %s(%s/%s) lookup returned error %d\n",
1133 __func__
, dentry
->d_parent
->d_name
.name
,
1134 dentry
->d_name
.name
, error
);
1139 * A weaker form of d_revalidate for revalidating just the dentry->d_inode
1140 * when we don't really care about the dentry name. This is called when a
1141 * pathwalk ends on a dentry that was not found via a normal lookup in the
1142 * parent dir (e.g.: ".", "..", procfs symlinks or mountpoint traversals).
1144 * In this situation, we just want to verify that the inode itself is OK
1145 * since the dentry might have changed on the server.
1147 static int nfs_weak_revalidate(struct dentry
*dentry
, unsigned int flags
)
1150 struct inode
*inode
= dentry
->d_inode
;
1153 * I believe we can only get a negative dentry here in the case of a
1154 * procfs-style symlink. Just assume it's correct for now, but we may
1155 * eventually need to do something more here.
1158 dfprintk(LOOKUPCACHE
, "%s: %s/%s has negative inode\n",
1159 __func__
, dentry
->d_parent
->d_name
.name
,
1160 dentry
->d_name
.name
);
1164 if (is_bad_inode(inode
)) {
1165 dfprintk(LOOKUPCACHE
, "%s: %s/%s has dud inode\n",
1166 __func__
, dentry
->d_parent
->d_name
.name
,
1167 dentry
->d_name
.name
);
1171 error
= nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
1172 dfprintk(LOOKUPCACHE
, "NFS: %s: inode %lu is %s\n",
1173 __func__
, inode
->i_ino
, error
? "invalid" : "valid");
1178 * This is called from dput() when d_count is going to 0.
1180 static int nfs_dentry_delete(const struct dentry
*dentry
)
1182 dfprintk(VFS
, "NFS: dentry_delete(%s/%s, %x)\n",
1183 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
1186 /* Unhash any dentry with a stale inode */
1187 if (dentry
->d_inode
!= NULL
&& NFS_STALE(dentry
->d_inode
))
1190 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1191 /* Unhash it, so that ->d_iput() would be called */
1194 if (!(dentry
->d_sb
->s_flags
& MS_ACTIVE
)) {
1195 /* Unhash it, so that ancestors of killed async unlink
1196 * files will be cleaned up during umount */
1203 /* Ensure that we revalidate inode->i_nlink */
1204 static void nfs_drop_nlink(struct inode
*inode
)
1206 spin_lock(&inode
->i_lock
);
1207 /* drop the inode if we're reasonably sure this is the last link */
1208 if (inode
->i_nlink
== 1)
1210 NFS_I(inode
)->cache_validity
|= NFS_INO_INVALID_ATTR
;
1211 spin_unlock(&inode
->i_lock
);
1215 * Called when the dentry loses inode.
1216 * We use it to clean up silly-renamed files.
1218 static void nfs_dentry_iput(struct dentry
*dentry
, struct inode
*inode
)
1220 if (S_ISDIR(inode
->i_mode
))
1221 /* drop any readdir cache as it could easily be old */
1222 NFS_I(inode
)->cache_validity
|= NFS_INO_INVALID_DATA
;
1224 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1225 nfs_complete_unlink(dentry
, inode
);
1226 nfs_drop_nlink(inode
);
1231 static void nfs_d_release(struct dentry
*dentry
)
1233 /* free cached devname value, if it survived that far */
1234 if (unlikely(dentry
->d_fsdata
)) {
1235 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
)
1238 kfree(dentry
->d_fsdata
);
1242 const struct dentry_operations nfs_dentry_operations
= {
1243 .d_revalidate
= nfs_lookup_revalidate
,
1244 .d_weak_revalidate
= nfs_weak_revalidate
,
1245 .d_delete
= nfs_dentry_delete
,
1246 .d_iput
= nfs_dentry_iput
,
1247 .d_automount
= nfs_d_automount
,
1248 .d_release
= nfs_d_release
,
1250 EXPORT_SYMBOL_GPL(nfs_dentry_operations
);
1252 struct dentry
*nfs_lookup(struct inode
*dir
, struct dentry
* dentry
, unsigned int flags
)
1255 struct dentry
*parent
;
1256 struct inode
*inode
= NULL
;
1257 struct nfs_fh
*fhandle
= NULL
;
1258 struct nfs_fattr
*fattr
= NULL
;
1261 dfprintk(VFS
, "NFS: lookup(%s/%s)\n",
1262 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
1263 nfs_inc_stats(dir
, NFSIOS_VFSLOOKUP
);
1265 res
= ERR_PTR(-ENAMETOOLONG
);
1266 if (dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
)
1270 * If we're doing an exclusive create, optimize away the lookup
1271 * but don't hash the dentry.
1273 if (nfs_is_exclusive_create(dir
, flags
)) {
1274 d_instantiate(dentry
, NULL
);
1279 res
= ERR_PTR(-ENOMEM
);
1280 fhandle
= nfs_alloc_fhandle();
1281 fattr
= nfs_alloc_fattr();
1282 if (fhandle
== NULL
|| fattr
== NULL
)
1285 parent
= dentry
->d_parent
;
1286 /* Protect against concurrent sillydeletes */
1287 nfs_block_sillyrename(parent
);
1288 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
);
1289 if (error
== -ENOENT
)
1292 res
= ERR_PTR(error
);
1293 goto out_unblock_sillyrename
;
1295 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
);
1296 res
= ERR_CAST(inode
);
1298 goto out_unblock_sillyrename
;
1300 /* Success: notify readdir to use READDIRPLUS */
1301 nfs_advise_use_readdirplus(dir
);
1304 res
= d_materialise_unique(dentry
, inode
);
1307 goto out_unblock_sillyrename
;
1310 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1311 out_unblock_sillyrename
:
1312 nfs_unblock_sillyrename(parent
);
1314 nfs_free_fattr(fattr
);
1315 nfs_free_fhandle(fhandle
);
1318 EXPORT_SYMBOL_GPL(nfs_lookup
);
1320 #if IS_ENABLED(CONFIG_NFS_V4)
1321 static int nfs4_lookup_revalidate(struct dentry
*, unsigned int);
1323 const struct dentry_operations nfs4_dentry_operations
= {
1324 .d_revalidate
= nfs4_lookup_revalidate
,
1325 .d_delete
= nfs_dentry_delete
,
1326 .d_iput
= nfs_dentry_iput
,
1327 .d_automount
= nfs_d_automount
,
1328 .d_release
= nfs_d_release
,
1330 EXPORT_SYMBOL_GPL(nfs4_dentry_operations
);
1332 static fmode_t
flags_to_mode(int flags
)
1334 fmode_t res
= (__force fmode_t
)flags
& FMODE_EXEC
;
1335 if ((flags
& O_ACCMODE
) != O_WRONLY
)
1337 if ((flags
& O_ACCMODE
) != O_RDONLY
)
1342 static struct nfs_open_context
*create_nfs_open_context(struct dentry
*dentry
, int open_flags
)
1344 return alloc_nfs_open_context(dentry
, flags_to_mode(open_flags
));
1347 static int do_open(struct inode
*inode
, struct file
*filp
)
1349 nfs_fscache_set_inode_cookie(inode
, filp
);
1353 static int nfs_finish_open(struct nfs_open_context
*ctx
,
1354 struct dentry
*dentry
,
1355 struct file
*file
, unsigned open_flags
,
1360 if (ctx
->dentry
!= dentry
) {
1362 ctx
->dentry
= dget(dentry
);
1365 /* If the open_intent is for execute, we have an extra check to make */
1366 if (ctx
->mode
& FMODE_EXEC
) {
1367 err
= nfs_may_open(dentry
->d_inode
, ctx
->cred
, open_flags
);
1372 err
= finish_open(file
, dentry
, do_open
, opened
);
1375 nfs_file_set_open_context(file
, ctx
);
1378 put_nfs_open_context(ctx
);
1382 int nfs_atomic_open(struct inode
*dir
, struct dentry
*dentry
,
1383 struct file
*file
, unsigned open_flags
,
1384 umode_t mode
, int *opened
)
1386 struct nfs_open_context
*ctx
;
1388 struct iattr attr
= { .ia_valid
= ATTR_OPEN
};
1389 struct inode
*inode
;
1392 /* Expect a negative dentry */
1393 BUG_ON(dentry
->d_inode
);
1395 dfprintk(VFS
, "NFS: atomic_open(%s/%ld), %s\n",
1396 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1398 /* NFS only supports OPEN on regular files */
1399 if ((open_flags
& O_DIRECTORY
)) {
1400 if (!d_unhashed(dentry
)) {
1402 * Hashed negative dentry with O_DIRECTORY: dentry was
1403 * revalidated and is fine, no need to perform lookup
1411 if (dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
)
1412 return -ENAMETOOLONG
;
1414 if (open_flags
& O_CREAT
) {
1415 attr
.ia_valid
|= ATTR_MODE
;
1416 attr
.ia_mode
= mode
& ~current_umask();
1418 if (open_flags
& O_TRUNC
) {
1419 attr
.ia_valid
|= ATTR_SIZE
;
1423 ctx
= create_nfs_open_context(dentry
, open_flags
);
1428 nfs_block_sillyrename(dentry
->d_parent
);
1429 inode
= NFS_PROTO(dir
)->open_context(dir
, ctx
, open_flags
, &attr
);
1431 if (IS_ERR(inode
)) {
1432 nfs_unblock_sillyrename(dentry
->d_parent
);
1433 put_nfs_open_context(ctx
);
1434 err
= PTR_ERR(inode
);
1437 d_add(dentry
, NULL
);
1443 if (!(open_flags
& O_NOFOLLOW
))
1452 res
= d_add_unique(dentry
, inode
);
1456 nfs_unblock_sillyrename(dentry
->d_parent
);
1457 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1459 err
= nfs_finish_open(ctx
, dentry
, file
, open_flags
, opened
);
1466 res
= nfs_lookup(dir
, dentry
, 0);
1471 return finish_no_open(file
, res
);
1473 EXPORT_SYMBOL_GPL(nfs_atomic_open
);
1475 static int nfs4_lookup_revalidate(struct dentry
*dentry
, unsigned int flags
)
1477 struct dentry
*parent
= NULL
;
1478 struct inode
*inode
;
1482 if (flags
& LOOKUP_RCU
)
1485 if (!(flags
& LOOKUP_OPEN
) || (flags
& LOOKUP_DIRECTORY
))
1487 if (d_mountpoint(dentry
))
1489 if (NFS_SB(dentry
->d_sb
)->caps
& NFS_CAP_ATOMIC_OPEN_V1
)
1492 inode
= dentry
->d_inode
;
1493 parent
= dget_parent(dentry
);
1494 dir
= parent
->d_inode
;
1496 /* We can't create new files in nfs_open_revalidate(), so we
1497 * optimize away revalidation of negative dentries.
1499 if (inode
== NULL
) {
1500 if (!nfs_neg_need_reval(dir
, dentry
, flags
))
1505 /* NFS only supports OPEN on regular files */
1506 if (!S_ISREG(inode
->i_mode
))
1508 /* We cannot do exclusive creation on a positive dentry */
1509 if (flags
& LOOKUP_EXCL
)
1512 /* Let f_op->open() actually open (and revalidate) the file */
1522 return nfs_lookup_revalidate(dentry
, flags
);
1525 #endif /* CONFIG_NFSV4 */
1528 * Code common to create, mkdir, and mknod.
1530 int nfs_instantiate(struct dentry
*dentry
, struct nfs_fh
*fhandle
,
1531 struct nfs_fattr
*fattr
)
1533 struct dentry
*parent
= dget_parent(dentry
);
1534 struct inode
*dir
= parent
->d_inode
;
1535 struct inode
*inode
;
1536 int error
= -EACCES
;
1540 /* We may have been initialized further down */
1541 if (dentry
->d_inode
)
1543 if (fhandle
->size
== 0) {
1544 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
);
1548 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1549 if (!(fattr
->valid
& NFS_ATTR_FATTR
)) {
1550 struct nfs_server
*server
= NFS_SB(dentry
->d_sb
);
1551 error
= server
->nfs_client
->rpc_ops
->getattr(server
, fhandle
, fattr
);
1555 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
);
1556 error
= PTR_ERR(inode
);
1559 d_add(dentry
, inode
);
1564 nfs_mark_for_revalidate(dir
);
1568 EXPORT_SYMBOL_GPL(nfs_instantiate
);
1571 * Following a failed create operation, we drop the dentry rather
1572 * than retain a negative dentry. This avoids a problem in the event
1573 * that the operation succeeded on the server, but an error in the
1574 * reply path made it appear to have failed.
1576 int nfs_create(struct inode
*dir
, struct dentry
*dentry
,
1577 umode_t mode
, bool excl
)
1580 int open_flags
= excl
? O_CREAT
| O_EXCL
: O_CREAT
;
1583 dfprintk(VFS
, "NFS: create(%s/%ld), %s\n",
1584 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1586 attr
.ia_mode
= mode
;
1587 attr
.ia_valid
= ATTR_MODE
;
1589 error
= NFS_PROTO(dir
)->create(dir
, dentry
, &attr
, open_flags
);
1597 EXPORT_SYMBOL_GPL(nfs_create
);
1600 * See comments for nfs_proc_create regarding failed operations.
1603 nfs_mknod(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
, dev_t rdev
)
1608 dfprintk(VFS
, "NFS: mknod(%s/%ld), %s\n",
1609 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1611 if (!new_valid_dev(rdev
))
1614 attr
.ia_mode
= mode
;
1615 attr
.ia_valid
= ATTR_MODE
;
1617 status
= NFS_PROTO(dir
)->mknod(dir
, dentry
, &attr
, rdev
);
1625 EXPORT_SYMBOL_GPL(nfs_mknod
);
1628 * See comments for nfs_proc_create regarding failed operations.
1630 int nfs_mkdir(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
)
1635 dfprintk(VFS
, "NFS: mkdir(%s/%ld), %s\n",
1636 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1638 attr
.ia_valid
= ATTR_MODE
;
1639 attr
.ia_mode
= mode
| S_IFDIR
;
1641 error
= NFS_PROTO(dir
)->mkdir(dir
, dentry
, &attr
);
1649 EXPORT_SYMBOL_GPL(nfs_mkdir
);
1651 static void nfs_dentry_handle_enoent(struct dentry
*dentry
)
1653 if (dentry
->d_inode
!= NULL
&& !d_unhashed(dentry
))
1657 int nfs_rmdir(struct inode
*dir
, struct dentry
*dentry
)
1661 dfprintk(VFS
, "NFS: rmdir(%s/%ld), %s\n",
1662 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1664 error
= NFS_PROTO(dir
)->rmdir(dir
, &dentry
->d_name
);
1665 /* Ensure the VFS deletes this inode */
1666 if (error
== 0 && dentry
->d_inode
!= NULL
)
1667 clear_nlink(dentry
->d_inode
);
1668 else if (error
== -ENOENT
)
1669 nfs_dentry_handle_enoent(dentry
);
1673 EXPORT_SYMBOL_GPL(nfs_rmdir
);
1676 * Remove a file after making sure there are no pending writes,
1677 * and after checking that the file has only one user.
1679 * We invalidate the attribute cache and free the inode prior to the operation
1680 * to avoid possible races if the server reuses the inode.
1682 static int nfs_safe_remove(struct dentry
*dentry
)
1684 struct inode
*dir
= dentry
->d_parent
->d_inode
;
1685 struct inode
*inode
= dentry
->d_inode
;
1688 dfprintk(VFS
, "NFS: safe_remove(%s/%s)\n",
1689 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
1691 /* If the dentry was sillyrenamed, we simply call d_delete() */
1692 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1697 if (inode
!= NULL
) {
1698 NFS_PROTO(inode
)->return_delegation(inode
);
1699 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1701 nfs_drop_nlink(inode
);
1703 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1704 if (error
== -ENOENT
)
1705 nfs_dentry_handle_enoent(dentry
);
1710 /* We do silly rename. In case sillyrename() returns -EBUSY, the inode
1711 * belongs to an active ".nfs..." file and we return -EBUSY.
1713 * If sillyrename() returns 0, we do nothing, otherwise we unlink.
1715 int nfs_unlink(struct inode
*dir
, struct dentry
*dentry
)
1718 int need_rehash
= 0;
1720 dfprintk(VFS
, "NFS: unlink(%s/%ld, %s)\n", dir
->i_sb
->s_id
,
1721 dir
->i_ino
, dentry
->d_name
.name
);
1723 spin_lock(&dentry
->d_lock
);
1724 if (dentry
->d_count
> 1) {
1725 spin_unlock(&dentry
->d_lock
);
1726 /* Start asynchronous writeout of the inode */
1727 write_inode_now(dentry
->d_inode
, 0);
1728 error
= nfs_sillyrename(dir
, dentry
);
1731 if (!d_unhashed(dentry
)) {
1735 spin_unlock(&dentry
->d_lock
);
1736 error
= nfs_safe_remove(dentry
);
1737 if (!error
|| error
== -ENOENT
) {
1738 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1739 } else if (need_rehash
)
1743 EXPORT_SYMBOL_GPL(nfs_unlink
);
1746 * To create a symbolic link, most file systems instantiate a new inode,
1747 * add a page to it containing the path, then write it out to the disk
1748 * using prepare_write/commit_write.
1750 * Unfortunately the NFS client can't create the in-core inode first
1751 * because it needs a file handle to create an in-core inode (see
1752 * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the
1753 * symlink request has completed on the server.
1755 * So instead we allocate a raw page, copy the symname into it, then do
1756 * the SYMLINK request with the page as the buffer. If it succeeds, we
1757 * now have a new file handle and can instantiate an in-core NFS inode
1758 * and move the raw page into its mapping.
1760 int nfs_symlink(struct inode
*dir
, struct dentry
*dentry
, const char *symname
)
1765 unsigned int pathlen
= strlen(symname
);
1768 dfprintk(VFS
, "NFS: symlink(%s/%ld, %s, %s)\n", dir
->i_sb
->s_id
,
1769 dir
->i_ino
, dentry
->d_name
.name
, symname
);
1771 if (pathlen
> PAGE_SIZE
)
1772 return -ENAMETOOLONG
;
1774 attr
.ia_mode
= S_IFLNK
| S_IRWXUGO
;
1775 attr
.ia_valid
= ATTR_MODE
;
1777 page
= alloc_page(GFP_HIGHUSER
);
1781 kaddr
= kmap_atomic(page
);
1782 memcpy(kaddr
, symname
, pathlen
);
1783 if (pathlen
< PAGE_SIZE
)
1784 memset(kaddr
+ pathlen
, 0, PAGE_SIZE
- pathlen
);
1785 kunmap_atomic(kaddr
);
1787 error
= NFS_PROTO(dir
)->symlink(dir
, dentry
, page
, pathlen
, &attr
);
1789 dfprintk(VFS
, "NFS: symlink(%s/%ld, %s, %s) error %d\n",
1790 dir
->i_sb
->s_id
, dir
->i_ino
,
1791 dentry
->d_name
.name
, symname
, error
);
1798 * No big deal if we can't add this page to the page cache here.
1799 * READLINK will get the missing page from the server if needed.
1801 if (!add_to_page_cache_lru(page
, dentry
->d_inode
->i_mapping
, 0,
1803 SetPageUptodate(page
);
1810 EXPORT_SYMBOL_GPL(nfs_symlink
);
1813 nfs_link(struct dentry
*old_dentry
, struct inode
*dir
, struct dentry
*dentry
)
1815 struct inode
*inode
= old_dentry
->d_inode
;
1818 dfprintk(VFS
, "NFS: link(%s/%s -> %s/%s)\n",
1819 old_dentry
->d_parent
->d_name
.name
, old_dentry
->d_name
.name
,
1820 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
1822 NFS_PROTO(inode
)->return_delegation(inode
);
1825 error
= NFS_PROTO(dir
)->link(inode
, dir
, &dentry
->d_name
);
1828 d_add(dentry
, inode
);
1832 EXPORT_SYMBOL_GPL(nfs_link
);
1836 * FIXME: Some nfsds, like the Linux user space nfsd, may generate a
1837 * different file handle for the same inode after a rename (e.g. when
1838 * moving to a different directory). A fail-safe method to do so would
1839 * be to look up old_dir/old_name, create a link to new_dir/new_name and
1840 * rename the old file using the sillyrename stuff. This way, the original
1841 * file in old_dir will go away when the last process iput()s the inode.
1845 * It actually works quite well. One needs to have the possibility for
1846 * at least one ".nfs..." file in each directory the file ever gets
1847 * moved or linked to which happens automagically with the new
1848 * implementation that only depends on the dcache stuff instead of
1849 * using the inode layer
1851 * Unfortunately, things are a little more complicated than indicated
1852 * above. For a cross-directory move, we want to make sure we can get
1853 * rid of the old inode after the operation. This means there must be
1854 * no pending writes (if it's a file), and the use count must be 1.
1855 * If these conditions are met, we can drop the dentries before doing
1858 int nfs_rename(struct inode
*old_dir
, struct dentry
*old_dentry
,
1859 struct inode
*new_dir
, struct dentry
*new_dentry
)
1861 struct inode
*old_inode
= old_dentry
->d_inode
;
1862 struct inode
*new_inode
= new_dentry
->d_inode
;
1863 struct dentry
*dentry
= NULL
, *rehash
= NULL
;
1866 dfprintk(VFS
, "NFS: rename(%s/%s -> %s/%s, ct=%d)\n",
1867 old_dentry
->d_parent
->d_name
.name
, old_dentry
->d_name
.name
,
1868 new_dentry
->d_parent
->d_name
.name
, new_dentry
->d_name
.name
,
1869 new_dentry
->d_count
);
1872 * For non-directories, check whether the target is busy and if so,
1873 * make a copy of the dentry and then do a silly-rename. If the
1874 * silly-rename succeeds, the copied dentry is hashed and becomes
1877 if (new_inode
&& !S_ISDIR(new_inode
->i_mode
)) {
1879 * To prevent any new references to the target during the
1880 * rename, we unhash the dentry in advance.
1882 if (!d_unhashed(new_dentry
)) {
1884 rehash
= new_dentry
;
1887 if (new_dentry
->d_count
> 2) {
1890 /* copy the target dentry's name */
1891 dentry
= d_alloc(new_dentry
->d_parent
,
1892 &new_dentry
->d_name
);
1896 /* silly-rename the existing target ... */
1897 err
= nfs_sillyrename(new_dir
, new_dentry
);
1901 new_dentry
= dentry
;
1907 NFS_PROTO(old_inode
)->return_delegation(old_inode
);
1908 if (new_inode
!= NULL
)
1909 NFS_PROTO(new_inode
)->return_delegation(new_inode
);
1911 error
= NFS_PROTO(old_dir
)->rename(old_dir
, &old_dentry
->d_name
,
1912 new_dir
, &new_dentry
->d_name
);
1913 nfs_mark_for_revalidate(old_inode
);
1918 if (new_inode
!= NULL
)
1919 nfs_drop_nlink(new_inode
);
1920 d_move(old_dentry
, new_dentry
);
1921 nfs_set_verifier(new_dentry
,
1922 nfs_save_change_attribute(new_dir
));
1923 } else if (error
== -ENOENT
)
1924 nfs_dentry_handle_enoent(old_dentry
);
1926 /* new dentry created? */
1931 EXPORT_SYMBOL_GPL(nfs_rename
);
1933 static DEFINE_SPINLOCK(nfs_access_lru_lock
);
1934 static LIST_HEAD(nfs_access_lru_list
);
1935 static atomic_long_t nfs_access_nr_entries
;
1937 static void nfs_access_free_entry(struct nfs_access_entry
*entry
)
1939 put_rpccred(entry
->cred
);
1941 smp_mb__before_atomic_dec();
1942 atomic_long_dec(&nfs_access_nr_entries
);
1943 smp_mb__after_atomic_dec();
1946 static void nfs_access_free_list(struct list_head
*head
)
1948 struct nfs_access_entry
*cache
;
1950 while (!list_empty(head
)) {
1951 cache
= list_entry(head
->next
, struct nfs_access_entry
, lru
);
1952 list_del(&cache
->lru
);
1953 nfs_access_free_entry(cache
);
1957 int nfs_access_cache_shrinker(struct shrinker
*shrink
,
1958 struct shrink_control
*sc
)
1961 struct nfs_inode
*nfsi
, *next
;
1962 struct nfs_access_entry
*cache
;
1963 int nr_to_scan
= sc
->nr_to_scan
;
1964 gfp_t gfp_mask
= sc
->gfp_mask
;
1966 if ((gfp_mask
& GFP_KERNEL
) != GFP_KERNEL
)
1967 return (nr_to_scan
== 0) ? 0 : -1;
1969 spin_lock(&nfs_access_lru_lock
);
1970 list_for_each_entry_safe(nfsi
, next
, &nfs_access_lru_list
, access_cache_inode_lru
) {
1971 struct inode
*inode
;
1973 if (nr_to_scan
-- == 0)
1975 inode
= &nfsi
->vfs_inode
;
1976 spin_lock(&inode
->i_lock
);
1977 if (list_empty(&nfsi
->access_cache_entry_lru
))
1978 goto remove_lru_entry
;
1979 cache
= list_entry(nfsi
->access_cache_entry_lru
.next
,
1980 struct nfs_access_entry
, lru
);
1981 list_move(&cache
->lru
, &head
);
1982 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
1983 if (!list_empty(&nfsi
->access_cache_entry_lru
))
1984 list_move_tail(&nfsi
->access_cache_inode_lru
,
1985 &nfs_access_lru_list
);
1988 list_del_init(&nfsi
->access_cache_inode_lru
);
1989 smp_mb__before_clear_bit();
1990 clear_bit(NFS_INO_ACL_LRU_SET
, &nfsi
->flags
);
1991 smp_mb__after_clear_bit();
1993 spin_unlock(&inode
->i_lock
);
1995 spin_unlock(&nfs_access_lru_lock
);
1996 nfs_access_free_list(&head
);
1997 return (atomic_long_read(&nfs_access_nr_entries
) / 100) * sysctl_vfs_cache_pressure
;
2000 static void __nfs_access_zap_cache(struct nfs_inode
*nfsi
, struct list_head
*head
)
2002 struct rb_root
*root_node
= &nfsi
->access_cache
;
2004 struct nfs_access_entry
*entry
;
2006 /* Unhook entries from the cache */
2007 while ((n
= rb_first(root_node
)) != NULL
) {
2008 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
2009 rb_erase(n
, root_node
);
2010 list_move(&entry
->lru
, head
);
2012 nfsi
->cache_validity
&= ~NFS_INO_INVALID_ACCESS
;
2015 void nfs_access_zap_cache(struct inode
*inode
)
2019 if (test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
) == 0)
2021 /* Remove from global LRU init */
2022 spin_lock(&nfs_access_lru_lock
);
2023 if (test_and_clear_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
2024 list_del_init(&NFS_I(inode
)->access_cache_inode_lru
);
2026 spin_lock(&inode
->i_lock
);
2027 __nfs_access_zap_cache(NFS_I(inode
), &head
);
2028 spin_unlock(&inode
->i_lock
);
2029 spin_unlock(&nfs_access_lru_lock
);
2030 nfs_access_free_list(&head
);
2032 EXPORT_SYMBOL_GPL(nfs_access_zap_cache
);
2034 static struct nfs_access_entry
*nfs_access_search_rbtree(struct inode
*inode
, struct rpc_cred
*cred
)
2036 struct rb_node
*n
= NFS_I(inode
)->access_cache
.rb_node
;
2037 struct nfs_access_entry
*entry
;
2040 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
2042 if (cred
< entry
->cred
)
2044 else if (cred
> entry
->cred
)
2052 static int nfs_access_get_cached(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_access_entry
*res
)
2054 struct nfs_inode
*nfsi
= NFS_I(inode
);
2055 struct nfs_access_entry
*cache
;
2058 spin_lock(&inode
->i_lock
);
2059 if (nfsi
->cache_validity
& NFS_INO_INVALID_ACCESS
)
2061 cache
= nfs_access_search_rbtree(inode
, cred
);
2064 if (!nfs_have_delegated_attributes(inode
) &&
2065 !time_in_range_open(jiffies
, cache
->jiffies
, cache
->jiffies
+ nfsi
->attrtimeo
))
2067 res
->jiffies
= cache
->jiffies
;
2068 res
->cred
= cache
->cred
;
2069 res
->mask
= cache
->mask
;
2070 list_move_tail(&cache
->lru
, &nfsi
->access_cache_entry_lru
);
2073 spin_unlock(&inode
->i_lock
);
2076 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
2077 list_del(&cache
->lru
);
2078 spin_unlock(&inode
->i_lock
);
2079 nfs_access_free_entry(cache
);
2082 spin_unlock(&inode
->i_lock
);
2083 nfs_access_zap_cache(inode
);
2087 static void nfs_access_add_rbtree(struct inode
*inode
, struct nfs_access_entry
*set
)
2089 struct nfs_inode
*nfsi
= NFS_I(inode
);
2090 struct rb_root
*root_node
= &nfsi
->access_cache
;
2091 struct rb_node
**p
= &root_node
->rb_node
;
2092 struct rb_node
*parent
= NULL
;
2093 struct nfs_access_entry
*entry
;
2095 spin_lock(&inode
->i_lock
);
2096 while (*p
!= NULL
) {
2098 entry
= rb_entry(parent
, struct nfs_access_entry
, rb_node
);
2100 if (set
->cred
< entry
->cred
)
2101 p
= &parent
->rb_left
;
2102 else if (set
->cred
> entry
->cred
)
2103 p
= &parent
->rb_right
;
2107 rb_link_node(&set
->rb_node
, parent
, p
);
2108 rb_insert_color(&set
->rb_node
, root_node
);
2109 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2110 spin_unlock(&inode
->i_lock
);
2113 rb_replace_node(parent
, &set
->rb_node
, root_node
);
2114 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2115 list_del(&entry
->lru
);
2116 spin_unlock(&inode
->i_lock
);
2117 nfs_access_free_entry(entry
);
2120 void nfs_access_add_cache(struct inode
*inode
, struct nfs_access_entry
*set
)
2122 struct nfs_access_entry
*cache
= kmalloc(sizeof(*cache
), GFP_KERNEL
);
2125 RB_CLEAR_NODE(&cache
->rb_node
);
2126 cache
->jiffies
= set
->jiffies
;
2127 cache
->cred
= get_rpccred(set
->cred
);
2128 cache
->mask
= set
->mask
;
2130 nfs_access_add_rbtree(inode
, cache
);
2132 /* Update accounting */
2133 smp_mb__before_atomic_inc();
2134 atomic_long_inc(&nfs_access_nr_entries
);
2135 smp_mb__after_atomic_inc();
2137 /* Add inode to global LRU list */
2138 if (!test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
)) {
2139 spin_lock(&nfs_access_lru_lock
);
2140 if (!test_and_set_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
2141 list_add_tail(&NFS_I(inode
)->access_cache_inode_lru
,
2142 &nfs_access_lru_list
);
2143 spin_unlock(&nfs_access_lru_lock
);
2146 EXPORT_SYMBOL_GPL(nfs_access_add_cache
);
2148 void nfs_access_set_mask(struct nfs_access_entry
*entry
, u32 access_result
)
2151 if (access_result
& NFS4_ACCESS_READ
)
2152 entry
->mask
|= MAY_READ
;
2154 (NFS4_ACCESS_MODIFY
| NFS4_ACCESS_EXTEND
| NFS4_ACCESS_DELETE
))
2155 entry
->mask
|= MAY_WRITE
;
2156 if (access_result
& (NFS4_ACCESS_LOOKUP
|NFS4_ACCESS_EXECUTE
))
2157 entry
->mask
|= MAY_EXEC
;
2159 EXPORT_SYMBOL_GPL(nfs_access_set_mask
);
2161 static int nfs_do_access(struct inode
*inode
, struct rpc_cred
*cred
, int mask
)
2163 struct nfs_access_entry cache
;
2166 status
= nfs_access_get_cached(inode
, cred
, &cache
);
2170 /* Be clever: ask server to check for all possible rights */
2171 cache
.mask
= MAY_EXEC
| MAY_WRITE
| MAY_READ
;
2173 cache
.jiffies
= jiffies
;
2174 status
= NFS_PROTO(inode
)->access(inode
, &cache
);
2176 if (status
== -ESTALE
) {
2177 nfs_zap_caches(inode
);
2178 if (!S_ISDIR(inode
->i_mode
))
2179 set_bit(NFS_INO_STALE
, &NFS_I(inode
)->flags
);
2183 nfs_access_add_cache(inode
, &cache
);
2185 if ((mask
& ~cache
.mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) == 0)
2190 static int nfs_open_permission_mask(int openflags
)
2194 if (openflags
& __FMODE_EXEC
) {
2195 /* ONLY check exec rights */
2198 if ((openflags
& O_ACCMODE
) != O_WRONLY
)
2200 if ((openflags
& O_ACCMODE
) != O_RDONLY
)
2207 int nfs_may_open(struct inode
*inode
, struct rpc_cred
*cred
, int openflags
)
2209 return nfs_do_access(inode
, cred
, nfs_open_permission_mask(openflags
));
2211 EXPORT_SYMBOL_GPL(nfs_may_open
);
2213 int nfs_permission(struct inode
*inode
, int mask
)
2215 struct rpc_cred
*cred
;
2218 if (mask
& MAY_NOT_BLOCK
)
2221 nfs_inc_stats(inode
, NFSIOS_VFSACCESS
);
2223 if ((mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) == 0)
2225 /* Is this sys_access() ? */
2226 if (mask
& (MAY_ACCESS
| MAY_CHDIR
))
2229 switch (inode
->i_mode
& S_IFMT
) {
2233 /* NFSv4 has atomic_open... */
2234 if (nfs_server_capable(inode
, NFS_CAP_ATOMIC_OPEN
)
2235 && (mask
& MAY_OPEN
)
2236 && !(mask
& MAY_EXEC
))
2241 * Optimize away all write operations, since the server
2242 * will check permissions when we perform the op.
2244 if ((mask
& MAY_WRITE
) && !(mask
& MAY_READ
))
2249 if (!NFS_PROTO(inode
)->access
)
2252 cred
= rpc_lookup_cred();
2253 if (!IS_ERR(cred
)) {
2254 res
= nfs_do_access(inode
, cred
, mask
);
2257 res
= PTR_ERR(cred
);
2259 if (!res
&& (mask
& MAY_EXEC
) && !execute_ok(inode
))
2262 dfprintk(VFS
, "NFS: permission(%s/%ld), mask=0x%x, res=%d\n",
2263 inode
->i_sb
->s_id
, inode
->i_ino
, mask
, res
);
2266 res
= nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
2268 res
= generic_permission(inode
, mask
);
2271 EXPORT_SYMBOL_GPL(nfs_permission
);
2275 * version-control: t
2276 * kept-new-versions: 5