1 // SPDX-License-Identifier: GPL-2.0-only
5 * Copyright (C) 1992 Rick Sladkey
7 * nfs directory handling functions
9 * 10 Apr 1996 Added silly rename for unlink --okir
10 * 28 Sep 1996 Improved directory cache --okir
11 * 23 Aug 1997 Claus Heine claus@momo.math.rwth-aachen.de
12 * Re-implemented silly rename for unlink, newly implemented
13 * silly rename for nfs_rename() following the suggestions
14 * of Olaf Kirch (okir) found in this file.
15 * Following Linus comments on my original hack, this version
16 * depends only on the dcache stuff and doesn't touch the inode
17 * layer (iput() and friends).
18 * 6 Jun 1999 Cache readdir lookups in the page cache. -DaveM
21 #include <linux/module.h>
22 #include <linux/time.h>
23 #include <linux/errno.h>
24 #include <linux/stat.h>
25 #include <linux/fcntl.h>
26 #include <linux/string.h>
27 #include <linux/kernel.h>
28 #include <linux/slab.h>
30 #include <linux/sunrpc/clnt.h>
31 #include <linux/nfs_fs.h>
32 #include <linux/nfs_mount.h>
33 #include <linux/pagemap.h>
34 #include <linux/pagevec.h>
35 #include <linux/namei.h>
36 #include <linux/mount.h>
37 #include <linux/swap.h>
38 #include <linux/sched.h>
39 #include <linux/kmemleak.h>
40 #include <linux/xattr.h>
42 #include "delegation.h"
49 /* #define NFS_DEBUG_VERBOSE 1 */
51 static int nfs_opendir(struct inode
*, struct file
*);
52 static int nfs_closedir(struct inode
*, struct file
*);
53 static int nfs_readdir(struct file
*, struct dir_context
*);
54 static int nfs_fsync_dir(struct file
*, loff_t
, loff_t
, int);
55 static loff_t
nfs_llseek_dir(struct file
*, loff_t
, int);
56 static void nfs_readdir_clear_array(struct page
*);
58 const struct file_operations nfs_dir_operations
= {
59 .llseek
= nfs_llseek_dir
,
60 .read
= generic_read_dir
,
61 .iterate_shared
= nfs_readdir
,
63 .release
= nfs_closedir
,
64 .fsync
= nfs_fsync_dir
,
67 const struct address_space_operations nfs_dir_aops
= {
68 .freepage
= nfs_readdir_clear_array
,
71 static struct nfs_open_dir_context
*alloc_nfs_open_dir_context(struct inode
*dir
)
73 struct nfs_inode
*nfsi
= NFS_I(dir
);
74 struct nfs_open_dir_context
*ctx
;
75 ctx
= kmalloc(sizeof(*ctx
), GFP_KERNEL
);
78 ctx
->attr_gencount
= nfsi
->attr_gencount
;
81 spin_lock(&dir
->i_lock
);
82 if (list_empty(&nfsi
->open_files
) &&
83 (nfsi
->cache_validity
& NFS_INO_DATA_INVAL_DEFER
))
84 nfsi
->cache_validity
|= NFS_INO_INVALID_DATA
|
86 list_add(&ctx
->list
, &nfsi
->open_files
);
87 spin_unlock(&dir
->i_lock
);
90 return ERR_PTR(-ENOMEM
);
93 static void put_nfs_open_dir_context(struct inode
*dir
, struct nfs_open_dir_context
*ctx
)
95 spin_lock(&dir
->i_lock
);
97 spin_unlock(&dir
->i_lock
);
105 nfs_opendir(struct inode
*inode
, struct file
*filp
)
108 struct nfs_open_dir_context
*ctx
;
110 dfprintk(FILE, "NFS: open dir(%pD2)\n", filp
);
112 nfs_inc_stats(inode
, NFSIOS_VFSOPEN
);
114 ctx
= alloc_nfs_open_dir_context(inode
);
119 filp
->private_data
= ctx
;
125 nfs_closedir(struct inode
*inode
, struct file
*filp
)
127 put_nfs_open_dir_context(file_inode(filp
), filp
->private_data
);
131 struct nfs_cache_array_entry
{
135 unsigned int name_len
;
136 unsigned char d_type
;
139 struct nfs_cache_array
{
142 unsigned char page_full
: 1,
144 cookies_are_ordered
: 1;
145 struct nfs_cache_array_entry array
[];
148 struct nfs_readdir_descriptor
{
151 struct dir_context
*ctx
;
156 loff_t current_index
;
159 __be32 verf
[NFS_DIR_VERIFIER_SIZE
];
160 unsigned long dir_verifier
;
161 unsigned long timestamp
;
162 unsigned long gencount
;
163 unsigned long attr_gencount
;
164 unsigned int cache_entry_index
;
170 static void nfs_readdir_array_init(struct nfs_cache_array
*array
)
172 memset(array
, 0, sizeof(struct nfs_cache_array
));
175 static void nfs_readdir_page_init_array(struct page
*page
, u64 last_cookie
)
177 struct nfs_cache_array
*array
;
179 array
= kmap_atomic(page
);
180 nfs_readdir_array_init(array
);
181 array
->last_cookie
= last_cookie
;
182 array
->cookies_are_ordered
= 1;
183 kunmap_atomic(array
);
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
].name
);
198 nfs_readdir_array_init(array
);
199 kunmap_atomic(array
);
203 nfs_readdir_page_array_alloc(u64 last_cookie
, gfp_t gfp_flags
)
205 struct page
*page
= alloc_page(gfp_flags
);
207 nfs_readdir_page_init_array(page
, last_cookie
);
211 static void nfs_readdir_page_array_free(struct page
*page
)
214 nfs_readdir_clear_array(page
);
219 static void nfs_readdir_array_set_eof(struct nfs_cache_array
*array
)
221 array
->page_is_eof
= 1;
222 array
->page_full
= 1;
225 static bool nfs_readdir_array_is_full(struct nfs_cache_array
*array
)
227 return array
->page_full
;
231 * the caller is responsible for freeing qstr.name
232 * when called by nfs_readdir_add_to_array, the strings will be freed in
233 * nfs_clear_readdir_array()
235 static const char *nfs_readdir_copy_name(const char *name
, unsigned int len
)
237 const char *ret
= kmemdup_nul(name
, len
, GFP_KERNEL
);
240 * Avoid a kmemleak false positive. The pointer to the name is stored
241 * in a page cache page which kmemleak does not scan.
244 kmemleak_not_leak(ret
);
249 * Check that the next array entry lies entirely within the page bounds
251 static int nfs_readdir_array_can_expand(struct nfs_cache_array
*array
)
253 struct nfs_cache_array_entry
*cache_entry
;
255 if (array
->page_full
)
257 cache_entry
= &array
->array
[array
->size
+ 1];
258 if ((char *)cache_entry
- (char *)array
> PAGE_SIZE
) {
259 array
->page_full
= 1;
266 int nfs_readdir_add_to_array(struct nfs_entry
*entry
, struct page
*page
)
268 struct nfs_cache_array
*array
;
269 struct nfs_cache_array_entry
*cache_entry
;
273 name
= nfs_readdir_copy_name(entry
->name
, entry
->len
);
277 array
= kmap_atomic(page
);
278 ret
= nfs_readdir_array_can_expand(array
);
284 cache_entry
= &array
->array
[array
->size
];
285 cache_entry
->cookie
= entry
->prev_cookie
;
286 cache_entry
->ino
= entry
->ino
;
287 cache_entry
->d_type
= entry
->d_type
;
288 cache_entry
->name_len
= entry
->len
;
289 cache_entry
->name
= name
;
290 array
->last_cookie
= entry
->cookie
;
291 if (array
->last_cookie
<= cache_entry
->cookie
)
292 array
->cookies_are_ordered
= 0;
295 nfs_readdir_array_set_eof(array
);
297 kunmap_atomic(array
);
301 static struct page
*nfs_readdir_page_get_locked(struct address_space
*mapping
,
302 pgoff_t index
, u64 last_cookie
)
306 page
= grab_cache_page(mapping
, index
);
307 if (page
&& !PageUptodate(page
)) {
308 nfs_readdir_page_init_array(page
, last_cookie
);
309 if (invalidate_inode_pages2_range(mapping
, index
+ 1, -1) < 0)
310 nfs_zap_mapping(mapping
->host
, mapping
);
311 SetPageUptodate(page
);
317 static u64
nfs_readdir_page_last_cookie(struct page
*page
)
319 struct nfs_cache_array
*array
;
322 array
= kmap_atomic(page
);
323 ret
= array
->last_cookie
;
324 kunmap_atomic(array
);
328 static bool nfs_readdir_page_needs_filling(struct page
*page
)
330 struct nfs_cache_array
*array
;
333 array
= kmap_atomic(page
);
334 ret
= !nfs_readdir_array_is_full(array
);
335 kunmap_atomic(array
);
339 static void nfs_readdir_page_set_eof(struct page
*page
)
341 struct nfs_cache_array
*array
;
343 array
= kmap_atomic(page
);
344 nfs_readdir_array_set_eof(array
);
345 kunmap_atomic(array
);
348 static void nfs_readdir_page_unlock_and_put(struct page
*page
)
354 static struct page
*nfs_readdir_page_get_next(struct address_space
*mapping
,
355 pgoff_t index
, u64 cookie
)
359 page
= nfs_readdir_page_get_locked(mapping
, index
, cookie
);
361 if (nfs_readdir_page_last_cookie(page
) == cookie
)
363 nfs_readdir_page_unlock_and_put(page
);
369 int is_32bit_api(void)
372 return in_compat_syscall();
374 return (BITS_PER_LONG
== 32);
379 bool nfs_readdir_use_cookie(const struct file
*filp
)
381 if ((filp
->f_mode
& FMODE_32BITHASH
) ||
382 (!(filp
->f_mode
& FMODE_64BITHASH
) && is_32bit_api()))
387 static int nfs_readdir_search_for_pos(struct nfs_cache_array
*array
,
388 struct nfs_readdir_descriptor
*desc
)
390 loff_t diff
= desc
->ctx
->pos
- desc
->current_index
;
395 if (diff
>= array
->size
) {
396 if (array
->page_is_eof
)
401 index
= (unsigned int)diff
;
402 desc
->dir_cookie
= array
->array
[index
].cookie
;
403 desc
->cache_entry_index
= index
;
411 nfs_readdir_inode_mapping_valid(struct nfs_inode
*nfsi
)
413 if (nfsi
->cache_validity
& (NFS_INO_INVALID_ATTR
|NFS_INO_INVALID_DATA
))
416 return !test_bit(NFS_INO_INVALIDATING
, &nfsi
->flags
);
419 static bool nfs_readdir_array_cookie_in_range(struct nfs_cache_array
*array
,
422 if (!array
->cookies_are_ordered
)
424 /* Optimisation for monotonically increasing cookies */
425 if (cookie
>= array
->last_cookie
)
427 if (array
->size
&& cookie
< array
->array
[0].cookie
)
432 static int nfs_readdir_search_for_cookie(struct nfs_cache_array
*array
,
433 struct nfs_readdir_descriptor
*desc
)
437 int status
= -EAGAIN
;
439 if (!nfs_readdir_array_cookie_in_range(array
, desc
->dir_cookie
))
442 for (i
= 0; i
< array
->size
; i
++) {
443 if (array
->array
[i
].cookie
== desc
->dir_cookie
) {
444 struct nfs_inode
*nfsi
= NFS_I(file_inode(desc
->file
));
446 new_pos
= desc
->current_index
+ i
;
447 if (desc
->attr_gencount
!= nfsi
->attr_gencount
||
448 !nfs_readdir_inode_mapping_valid(nfsi
)) {
450 desc
->attr_gencount
= nfsi
->attr_gencount
;
451 } else if (new_pos
< desc
->prev_index
) {
453 && desc
->dup_cookie
== desc
->dir_cookie
) {
454 if (printk_ratelimit()) {
455 pr_notice("NFS: directory %pD2 contains a readdir loop."
456 "Please contact your server vendor. "
457 "The file: %s has duplicate cookie %llu\n",
458 desc
->file
, array
->array
[i
].name
, desc
->dir_cookie
);
463 desc
->dup_cookie
= desc
->dir_cookie
;
466 if (nfs_readdir_use_cookie(desc
->file
))
467 desc
->ctx
->pos
= desc
->dir_cookie
;
469 desc
->ctx
->pos
= new_pos
;
470 desc
->prev_index
= new_pos
;
471 desc
->cache_entry_index
= i
;
476 if (array
->page_is_eof
) {
477 status
= -EBADCOOKIE
;
478 if (desc
->dir_cookie
== array
->last_cookie
)
485 static int nfs_readdir_search_array(struct nfs_readdir_descriptor
*desc
)
487 struct nfs_cache_array
*array
;
490 array
= kmap_atomic(desc
->page
);
492 if (desc
->dir_cookie
== 0)
493 status
= nfs_readdir_search_for_pos(array
, desc
);
495 status
= nfs_readdir_search_for_cookie(array
, desc
);
497 if (status
== -EAGAIN
) {
498 desc
->last_cookie
= array
->last_cookie
;
499 desc
->current_index
+= array
->size
;
502 kunmap_atomic(array
);
506 /* Fill a page with xdr information before transferring to the cache page */
507 static int nfs_readdir_xdr_filler(struct nfs_readdir_descriptor
*desc
,
508 __be32
*verf
, u64 cookie
,
509 struct page
**pages
, size_t bufsize
,
512 struct inode
*inode
= file_inode(desc
->file
);
513 struct nfs_readdir_arg arg
= {
514 .dentry
= file_dentry(desc
->file
),
515 .cred
= desc
->file
->f_cred
,
522 struct nfs_readdir_res res
= {
525 unsigned long timestamp
, gencount
;
530 gencount
= nfs_inc_attr_generation_counter();
531 desc
->dir_verifier
= nfs_save_change_attribute(inode
);
532 error
= NFS_PROTO(inode
)->readdir(&arg
, &res
);
534 /* We requested READDIRPLUS, but the server doesn't grok it */
535 if (error
== -ENOTSUPP
&& desc
->plus
) {
536 NFS_SERVER(inode
)->caps
&= ~NFS_CAP_READDIRPLUS
;
537 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
538 desc
->plus
= arg
.plus
= false;
543 desc
->timestamp
= timestamp
;
544 desc
->gencount
= gencount
;
549 static int xdr_decode(struct nfs_readdir_descriptor
*desc
,
550 struct nfs_entry
*entry
, struct xdr_stream
*xdr
)
552 struct inode
*inode
= file_inode(desc
->file
);
555 error
= NFS_PROTO(inode
)->decode_dirent(xdr
, entry
, desc
->plus
);
558 entry
->fattr
->time_start
= desc
->timestamp
;
559 entry
->fattr
->gencount
= desc
->gencount
;
563 /* Match file and dirent using either filehandle or fileid
564 * Note: caller is responsible for checking the fsid
567 int nfs_same_file(struct dentry
*dentry
, struct nfs_entry
*entry
)
570 struct nfs_inode
*nfsi
;
572 if (d_really_is_negative(dentry
))
575 inode
= d_inode(dentry
);
576 if (is_bad_inode(inode
) || NFS_STALE(inode
))
580 if (entry
->fattr
->fileid
!= nfsi
->fileid
)
582 if (entry
->fh
->size
&& nfs_compare_fh(entry
->fh
, &nfsi
->fh
) != 0)
588 bool nfs_use_readdirplus(struct inode
*dir
, struct dir_context
*ctx
)
590 if (!nfs_server_capable(dir
, NFS_CAP_READDIRPLUS
))
592 if (test_and_clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(dir
)->flags
))
600 * This function is called by the lookup and getattr code to request the
601 * use of readdirplus to accelerate any future lookups in the same
604 void nfs_advise_use_readdirplus(struct inode
*dir
)
606 struct nfs_inode
*nfsi
= NFS_I(dir
);
608 if (nfs_server_capable(dir
, NFS_CAP_READDIRPLUS
) &&
609 !list_empty(&nfsi
->open_files
))
610 set_bit(NFS_INO_ADVISE_RDPLUS
, &nfsi
->flags
);
614 * This function is mainly for use by nfs_getattr().
616 * If this is an 'ls -l', we want to force use of readdirplus.
617 * Do this by checking if there is an active file descriptor
618 * and calling nfs_advise_use_readdirplus, then forcing a
621 void nfs_force_use_readdirplus(struct inode
*dir
)
623 struct nfs_inode
*nfsi
= NFS_I(dir
);
625 if (nfs_server_capable(dir
, NFS_CAP_READDIRPLUS
) &&
626 !list_empty(&nfsi
->open_files
)) {
627 set_bit(NFS_INO_ADVISE_RDPLUS
, &nfsi
->flags
);
628 invalidate_mapping_pages(dir
->i_mapping
,
629 nfsi
->page_index
+ 1, -1);
634 void nfs_prime_dcache(struct dentry
*parent
, struct nfs_entry
*entry
,
635 unsigned long dir_verifier
)
637 struct qstr filename
= QSTR_INIT(entry
->name
, entry
->len
);
638 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq
);
639 struct dentry
*dentry
;
640 struct dentry
*alias
;
644 if (!(entry
->fattr
->valid
& NFS_ATTR_FATTR_FILEID
))
646 if (!(entry
->fattr
->valid
& NFS_ATTR_FATTR_FSID
))
648 if (filename
.len
== 0)
650 /* Validate that the name doesn't contain any illegal '\0' */
651 if (strnlen(filename
.name
, filename
.len
) != filename
.len
)
654 if (strnchr(filename
.name
, filename
.len
, '/'))
656 if (filename
.name
[0] == '.') {
657 if (filename
.len
== 1)
659 if (filename
.len
== 2 && filename
.name
[1] == '.')
662 filename
.hash
= full_name_hash(parent
, filename
.name
, filename
.len
);
664 dentry
= d_lookup(parent
, &filename
);
667 dentry
= d_alloc_parallel(parent
, &filename
, &wq
);
671 if (!d_in_lookup(dentry
)) {
672 /* Is there a mountpoint here? If so, just exit */
673 if (!nfs_fsid_equal(&NFS_SB(dentry
->d_sb
)->fsid
,
674 &entry
->fattr
->fsid
))
676 if (nfs_same_file(dentry
, entry
)) {
677 if (!entry
->fh
->size
)
679 nfs_set_verifier(dentry
, dir_verifier
);
680 status
= nfs_refresh_inode(d_inode(dentry
), entry
->fattr
);
682 nfs_setsecurity(d_inode(dentry
), entry
->fattr
, entry
->label
);
685 d_invalidate(dentry
);
691 if (!entry
->fh
->size
) {
692 d_lookup_done(dentry
);
696 inode
= nfs_fhget(dentry
->d_sb
, entry
->fh
, entry
->fattr
, entry
->label
);
697 alias
= d_splice_alias(inode
, dentry
);
698 d_lookup_done(dentry
);
705 nfs_set_verifier(dentry
, dir_verifier
);
710 /* Perform conversion from xdr to cache array */
711 static int nfs_readdir_page_filler(struct nfs_readdir_descriptor
*desc
,
712 struct nfs_entry
*entry
,
713 struct page
**xdr_pages
,
715 struct page
**arrays
,
718 struct address_space
*mapping
= desc
->file
->f_mapping
;
719 struct xdr_stream stream
;
721 struct page
*scratch
, *new, *page
= *arrays
;
724 scratch
= alloc_page(GFP_KERNEL
);
728 xdr_init_decode_pages(&stream
, &buf
, xdr_pages
, buflen
);
729 xdr_set_scratch_page(&stream
, scratch
);
733 entry
->label
->len
= NFS4_MAXLABELLEN
;
735 status
= xdr_decode(desc
, entry
, &stream
);
740 nfs_prime_dcache(file_dentry(desc
->file
), entry
,
743 status
= nfs_readdir_add_to_array(entry
, page
);
744 if (status
!= -ENOSPC
)
747 if (page
->mapping
!= mapping
) {
750 new = nfs_readdir_page_array_alloc(entry
->prev_cookie
,
755 *arrays
= page
= new;
757 new = nfs_readdir_page_get_next(mapping
,
763 nfs_readdir_page_unlock_and_put(page
);
766 status
= nfs_readdir_add_to_array(entry
, page
);
767 } while (!status
&& !entry
->eof
);
772 nfs_readdir_page_set_eof(page
);
783 nfs_readdir_page_unlock_and_put(page
);
789 static void nfs_readdir_free_pages(struct page
**pages
, size_t npages
)
792 put_page(pages
[npages
]);
797 * nfs_readdir_alloc_pages() will allocate pages that must be freed with a call
798 * to nfs_readdir_free_pages()
800 static struct page
**nfs_readdir_alloc_pages(size_t npages
)
805 pages
= kmalloc_array(npages
, sizeof(*pages
), GFP_KERNEL
);
808 for (i
= 0; i
< npages
; i
++) {
809 struct page
*page
= alloc_page(GFP_KERNEL
);
817 nfs_readdir_free_pages(pages
, i
);
821 static int nfs_readdir_xdr_to_array(struct nfs_readdir_descriptor
*desc
,
822 __be32
*verf_arg
, __be32
*verf_res
,
823 struct page
**arrays
, size_t narrays
)
826 struct page
*page
= *arrays
;
827 struct nfs_entry
*entry
;
829 struct inode
*inode
= file_inode(desc
->file
);
830 size_t dtsize
= NFS_SERVER(inode
)->dtsize
;
831 int status
= -ENOMEM
;
833 entry
= kzalloc(sizeof(*entry
), GFP_KERNEL
);
836 entry
->cookie
= nfs_readdir_page_last_cookie(page
);
837 entry
->fh
= nfs_alloc_fhandle();
838 entry
->fattr
= nfs_alloc_fattr();
839 entry
->server
= NFS_SERVER(inode
);
840 if (entry
->fh
== NULL
|| entry
->fattr
== NULL
)
843 entry
->label
= nfs4_label_alloc(NFS_SERVER(inode
), GFP_NOWAIT
);
844 if (IS_ERR(entry
->label
)) {
845 status
= PTR_ERR(entry
->label
);
849 array_size
= (dtsize
+ PAGE_SIZE
- 1) >> PAGE_SHIFT
;
850 pages
= nfs_readdir_alloc_pages(array_size
);
852 goto out_release_label
;
856 status
= nfs_readdir_xdr_filler(desc
, verf_arg
, entry
->cookie
,
864 nfs_readdir_page_set_eof(page
);
868 status
= nfs_readdir_page_filler(desc
, entry
, pages
, pglen
,
870 } while (!status
&& nfs_readdir_page_needs_filling(page
));
872 nfs_readdir_free_pages(pages
, array_size
);
874 nfs4_label_free(entry
->label
);
876 nfs_free_fattr(entry
->fattr
);
877 nfs_free_fhandle(entry
->fh
);
882 static void nfs_readdir_page_put(struct nfs_readdir_descriptor
*desc
)
884 put_page(desc
->page
);
889 nfs_readdir_page_unlock_and_put_cached(struct nfs_readdir_descriptor
*desc
)
891 unlock_page(desc
->page
);
892 nfs_readdir_page_put(desc
);
896 nfs_readdir_page_get_cached(struct nfs_readdir_descriptor
*desc
)
898 return nfs_readdir_page_get_locked(desc
->file
->f_mapping
,
904 * Returns 0 if desc->dir_cookie was found on page desc->page_index
905 * and locks the page to prevent removal from the page cache.
907 static int find_and_lock_cache_page(struct nfs_readdir_descriptor
*desc
)
909 struct inode
*inode
= file_inode(desc
->file
);
910 struct nfs_inode
*nfsi
= NFS_I(inode
);
911 __be32 verf
[NFS_DIR_VERIFIER_SIZE
];
914 desc
->page
= nfs_readdir_page_get_cached(desc
);
917 if (nfs_readdir_page_needs_filling(desc
->page
)) {
918 res
= nfs_readdir_xdr_to_array(desc
, nfsi
->cookieverf
, verf
,
921 nfs_readdir_page_unlock_and_put_cached(desc
);
922 if (res
== -EBADCOOKIE
|| res
== -ENOTSYNC
) {
923 invalidate_inode_pages2(desc
->file
->f_mapping
);
924 desc
->page_index
= 0;
929 memcpy(nfsi
->cookieverf
, verf
, sizeof(nfsi
->cookieverf
));
931 res
= nfs_readdir_search_array(desc
);
933 nfsi
->page_index
= desc
->page_index
;
936 nfs_readdir_page_unlock_and_put_cached(desc
);
940 static bool nfs_readdir_dont_search_cache(struct nfs_readdir_descriptor
*desc
)
942 struct address_space
*mapping
= desc
->file
->f_mapping
;
943 struct inode
*dir
= file_inode(desc
->file
);
944 unsigned int dtsize
= NFS_SERVER(dir
)->dtsize
;
945 loff_t size
= i_size_read(dir
);
948 * Default to uncached readdir if the page cache is empty, and
949 * we're looking for a non-zero cookie in a large directory.
951 return desc
->dir_cookie
!= 0 && mapping
->nrpages
== 0 && size
> dtsize
;
954 /* Search for desc->dir_cookie from the beginning of the page cache */
955 static int readdir_search_pagecache(struct nfs_readdir_descriptor
*desc
)
959 if (nfs_readdir_dont_search_cache(desc
))
963 if (desc
->page_index
== 0) {
964 desc
->current_index
= 0;
965 desc
->prev_index
= 0;
966 desc
->last_cookie
= 0;
968 res
= find_and_lock_cache_page(desc
);
969 } while (res
== -EAGAIN
);
974 * Once we've found the start of the dirent within a page: fill 'er up...
976 static void nfs_do_filldir(struct nfs_readdir_descriptor
*desc
)
978 struct file
*file
= desc
->file
;
979 struct nfs_inode
*nfsi
= NFS_I(file_inode(file
));
980 struct nfs_cache_array
*array
;
983 array
= kmap(desc
->page
);
984 for (i
= desc
->cache_entry_index
; i
< array
->size
; i
++) {
985 struct nfs_cache_array_entry
*ent
;
987 ent
= &array
->array
[i
];
988 if (!dir_emit(desc
->ctx
, ent
->name
, ent
->name_len
,
989 nfs_compat_user_ino64(ent
->ino
), ent
->d_type
)) {
993 memcpy(desc
->verf
, nfsi
->cookieverf
, sizeof(desc
->verf
));
994 if (i
< (array
->size
-1))
995 desc
->dir_cookie
= array
->array
[i
+1].cookie
;
997 desc
->dir_cookie
= array
->last_cookie
;
998 if (nfs_readdir_use_cookie(file
))
999 desc
->ctx
->pos
= desc
->dir_cookie
;
1002 if (desc
->duped
!= 0)
1005 if (array
->page_is_eof
)
1009 dfprintk(DIRCACHE
, "NFS: nfs_do_filldir() filling ended @ cookie %llu\n",
1010 (unsigned long long)desc
->dir_cookie
);
1014 * If we cannot find a cookie in our cache, we suspect that this is
1015 * because it points to a deleted file, so we ask the server to return
1016 * whatever it thinks is the next entry. We then feed this to filldir.
1017 * If all goes well, we should then be able to find our way round the
1018 * cache on the next call to readdir_search_pagecache();
1020 * NOTE: we cannot add the anonymous page to the pagecache because
1021 * the data it contains might not be page aligned. Besides,
1022 * we should already have a complete representation of the
1023 * directory in the page cache by the time we get here.
1025 static int uncached_readdir(struct nfs_readdir_descriptor
*desc
)
1027 struct page
**arrays
;
1029 __be32 verf
[NFS_DIR_VERIFIER_SIZE
];
1030 int status
= -ENOMEM
;
1032 dfprintk(DIRCACHE
, "NFS: uncached_readdir() searching for cookie %llu\n",
1033 (unsigned long long)desc
->dir_cookie
);
1035 arrays
= kcalloc(sz
, sizeof(*arrays
), GFP_KERNEL
);
1038 arrays
[0] = nfs_readdir_page_array_alloc(desc
->dir_cookie
, GFP_KERNEL
);
1042 desc
->page_index
= 0;
1043 desc
->last_cookie
= desc
->dir_cookie
;
1046 status
= nfs_readdir_xdr_to_array(desc
, desc
->verf
, verf
, arrays
, sz
);
1048 for (i
= 0; !desc
->eof
&& i
< sz
&& arrays
[i
]; i
++) {
1049 desc
->page
= arrays
[i
];
1050 nfs_do_filldir(desc
);
1055 for (i
= 0; i
< sz
&& arrays
[i
]; i
++)
1056 nfs_readdir_page_array_free(arrays
[i
]);
1059 dfprintk(DIRCACHE
, "NFS: %s: returns %d\n", __func__
, status
);
1063 /* The file offset position represents the dirent entry number. A
1064 last cookie cache takes care of the common case of reading the
1067 static int nfs_readdir(struct file
*file
, struct dir_context
*ctx
)
1069 struct dentry
*dentry
= file_dentry(file
);
1070 struct inode
*inode
= d_inode(dentry
);
1071 struct nfs_open_dir_context
*dir_ctx
= file
->private_data
;
1072 struct nfs_readdir_descriptor
*desc
;
1075 dfprintk(FILE, "NFS: readdir(%pD2) starting at cookie %llu\n",
1076 file
, (long long)ctx
->pos
);
1077 nfs_inc_stats(inode
, NFSIOS_VFSGETDENTS
);
1080 * ctx->pos points to the dirent entry number.
1081 * *desc->dir_cookie has the cookie for the next entry. We have
1082 * to either find the entry with the appropriate number or
1083 * revalidate the cookie.
1085 if (ctx
->pos
== 0 || nfs_attribute_cache_expired(inode
)) {
1086 res
= nfs_revalidate_mapping(inode
, file
->f_mapping
);
1092 desc
= kzalloc(sizeof(*desc
), GFP_KERNEL
);
1097 desc
->plus
= nfs_use_readdirplus(inode
, ctx
);
1099 spin_lock(&file
->f_lock
);
1100 desc
->dir_cookie
= dir_ctx
->dir_cookie
;
1101 desc
->dup_cookie
= dir_ctx
->dup_cookie
;
1102 desc
->duped
= dir_ctx
->duped
;
1103 desc
->attr_gencount
= dir_ctx
->attr_gencount
;
1104 memcpy(desc
->verf
, dir_ctx
->verf
, sizeof(desc
->verf
));
1105 spin_unlock(&file
->f_lock
);
1108 res
= readdir_search_pagecache(desc
);
1110 if (res
== -EBADCOOKIE
) {
1112 /* This means either end of directory */
1113 if (desc
->dir_cookie
&& !desc
->eof
) {
1114 /* Or that the server has 'lost' a cookie */
1115 res
= uncached_readdir(desc
);
1118 if (res
== -EBADCOOKIE
|| res
== -ENOTSYNC
)
1123 if (res
== -ETOOSMALL
&& desc
->plus
) {
1124 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
1125 nfs_zap_caches(inode
);
1126 desc
->page_index
= 0;
1134 nfs_do_filldir(desc
);
1135 nfs_readdir_page_unlock_and_put_cached(desc
);
1136 } while (!desc
->eof
);
1138 spin_lock(&file
->f_lock
);
1139 dir_ctx
->dir_cookie
= desc
->dir_cookie
;
1140 dir_ctx
->dup_cookie
= desc
->dup_cookie
;
1141 dir_ctx
->duped
= desc
->duped
;
1142 dir_ctx
->attr_gencount
= desc
->attr_gencount
;
1143 memcpy(dir_ctx
->verf
, desc
->verf
, sizeof(dir_ctx
->verf
));
1144 spin_unlock(&file
->f_lock
);
1149 dfprintk(FILE, "NFS: readdir(%pD2) returns %d\n", file
, res
);
1153 static loff_t
nfs_llseek_dir(struct file
*filp
, loff_t offset
, int whence
)
1155 struct nfs_open_dir_context
*dir_ctx
= filp
->private_data
;
1157 dfprintk(FILE, "NFS: llseek dir(%pD2, %lld, %d)\n",
1158 filp
, offset
, whence
);
1166 spin_lock(&filp
->f_lock
);
1171 spin_lock(&filp
->f_lock
);
1172 offset
+= filp
->f_pos
;
1174 spin_unlock(&filp
->f_lock
);
1178 if (offset
!= filp
->f_pos
) {
1179 filp
->f_pos
= offset
;
1180 if (nfs_readdir_use_cookie(filp
))
1181 dir_ctx
->dir_cookie
= offset
;
1183 dir_ctx
->dir_cookie
= 0;
1185 memset(dir_ctx
->verf
, 0, sizeof(dir_ctx
->verf
));
1188 spin_unlock(&filp
->f_lock
);
1193 * All directory operations under NFS are synchronous, so fsync()
1194 * is a dummy operation.
1196 static int nfs_fsync_dir(struct file
*filp
, loff_t start
, loff_t end
,
1199 dfprintk(FILE, "NFS: fsync dir(%pD2) datasync %d\n", filp
, datasync
);
1201 nfs_inc_stats(file_inode(filp
), NFSIOS_VFSFSYNC
);
1206 * nfs_force_lookup_revalidate - Mark the directory as having changed
1207 * @dir: pointer to directory inode
1209 * This forces the revalidation code in nfs_lookup_revalidate() to do a
1210 * full lookup on all child dentries of 'dir' whenever a change occurs
1211 * on the server that might have invalidated our dcache.
1213 * Note that we reserve bit '0' as a tag to let us know when a dentry
1214 * was revalidated while holding a delegation on its inode.
1216 * The caller should be holding dir->i_lock
1218 void nfs_force_lookup_revalidate(struct inode
*dir
)
1220 NFS_I(dir
)->cache_change_attribute
+= 2;
1222 EXPORT_SYMBOL_GPL(nfs_force_lookup_revalidate
);
1225 * nfs_verify_change_attribute - Detects NFS remote directory changes
1226 * @dir: pointer to parent directory inode
1227 * @verf: previously saved change attribute
1229 * Return "false" if the verifiers doesn't match the change attribute.
1230 * This would usually indicate that the directory contents have changed on
1231 * the server, and that any dentries need revalidating.
1233 static bool nfs_verify_change_attribute(struct inode
*dir
, unsigned long verf
)
1235 return (verf
& ~1UL) == nfs_save_change_attribute(dir
);
1238 static void nfs_set_verifier_delegated(unsigned long *verf
)
1243 #if IS_ENABLED(CONFIG_NFS_V4)
1244 static void nfs_unset_verifier_delegated(unsigned long *verf
)
1248 #endif /* IS_ENABLED(CONFIG_NFS_V4) */
1250 static bool nfs_test_verifier_delegated(unsigned long verf
)
1255 static bool nfs_verifier_is_delegated(struct dentry
*dentry
)
1257 return nfs_test_verifier_delegated(dentry
->d_time
);
1260 static void nfs_set_verifier_locked(struct dentry
*dentry
, unsigned long verf
)
1262 struct inode
*inode
= d_inode(dentry
);
1264 if (!nfs_verifier_is_delegated(dentry
) &&
1265 !nfs_verify_change_attribute(d_inode(dentry
->d_parent
), verf
))
1267 if (inode
&& NFS_PROTO(inode
)->have_delegation(inode
, FMODE_READ
))
1268 nfs_set_verifier_delegated(&verf
);
1270 dentry
->d_time
= verf
;
1274 * nfs_set_verifier - save a parent directory verifier in the dentry
1275 * @dentry: pointer to dentry
1276 * @verf: verifier to save
1278 * Saves the parent directory verifier in @dentry. If the inode has
1279 * a delegation, we also tag the dentry as having been revalidated
1280 * while holding a delegation so that we know we don't have to
1281 * look it up again after a directory change.
1283 void nfs_set_verifier(struct dentry
*dentry
, unsigned long verf
)
1286 spin_lock(&dentry
->d_lock
);
1287 nfs_set_verifier_locked(dentry
, verf
);
1288 spin_unlock(&dentry
->d_lock
);
1290 EXPORT_SYMBOL_GPL(nfs_set_verifier
);
1292 #if IS_ENABLED(CONFIG_NFS_V4)
1294 * nfs_clear_verifier_delegated - clear the dir verifier delegation tag
1295 * @inode: pointer to inode
1297 * Iterates through the dentries in the inode alias list and clears
1298 * the tag used to indicate that the dentry has been revalidated
1299 * while holding a delegation.
1300 * This function is intended for use when the delegation is being
1301 * returned or revoked.
1303 void nfs_clear_verifier_delegated(struct inode
*inode
)
1305 struct dentry
*alias
;
1309 spin_lock(&inode
->i_lock
);
1310 hlist_for_each_entry(alias
, &inode
->i_dentry
, d_u
.d_alias
) {
1311 spin_lock(&alias
->d_lock
);
1312 nfs_unset_verifier_delegated(&alias
->d_time
);
1313 spin_unlock(&alias
->d_lock
);
1315 spin_unlock(&inode
->i_lock
);
1317 EXPORT_SYMBOL_GPL(nfs_clear_verifier_delegated
);
1318 #endif /* IS_ENABLED(CONFIG_NFS_V4) */
1321 * A check for whether or not the parent directory has changed.
1322 * In the case it has, we assume that the dentries are untrustworthy
1323 * and may need to be looked up again.
1324 * If rcu_walk prevents us from performing a full check, return 0.
1326 static int nfs_check_verifier(struct inode
*dir
, struct dentry
*dentry
,
1329 if (IS_ROOT(dentry
))
1331 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONE
)
1333 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
1335 /* Revalidate nfsi->cache_change_attribute before we declare a match */
1336 if (nfs_mapping_need_revalidate_inode(dir
)) {
1339 if (__nfs_revalidate_inode(NFS_SERVER(dir
), dir
) < 0)
1342 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
1348 * Use intent information to check whether or not we're going to do
1349 * an O_EXCL create using this path component.
1351 static int nfs_is_exclusive_create(struct inode
*dir
, unsigned int flags
)
1353 if (NFS_PROTO(dir
)->version
== 2)
1355 return flags
& LOOKUP_EXCL
;
1359 * Inode and filehandle revalidation for lookups.
1361 * We force revalidation in the cases where the VFS sets LOOKUP_REVAL,
1362 * or if the intent information indicates that we're about to open this
1363 * particular file and the "nocto" mount flag is not set.
1367 int nfs_lookup_verify_inode(struct inode
*inode
, unsigned int flags
)
1369 struct nfs_server
*server
= NFS_SERVER(inode
);
1372 if (IS_AUTOMOUNT(inode
))
1375 if (flags
& LOOKUP_OPEN
) {
1376 switch (inode
->i_mode
& S_IFMT
) {
1378 /* A NFSv4 OPEN will revalidate later */
1379 if (server
->caps
& NFS_CAP_ATOMIC_OPEN
)
1383 if (server
->flags
& NFS_MOUNT_NOCTO
)
1385 /* NFS close-to-open cache consistency validation */
1390 /* VFS wants an on-the-wire revalidation */
1391 if (flags
& LOOKUP_REVAL
)
1394 return (inode
->i_nlink
== 0) ? -ESTALE
: 0;
1396 if (flags
& LOOKUP_RCU
)
1398 ret
= __nfs_revalidate_inode(server
, inode
);
1405 * We judge how long we want to trust negative
1406 * dentries by looking at the parent inode mtime.
1408 * If parent mtime has changed, we revalidate, else we wait for a
1409 * period corresponding to the parent's attribute cache timeout value.
1411 * If LOOKUP_RCU prevents us from performing a full check, return 1
1412 * suggesting a reval is needed.
1414 * Note that when creating a new file, or looking up a rename target,
1415 * then it shouldn't be necessary to revalidate a negative dentry.
1418 int nfs_neg_need_reval(struct inode
*dir
, struct dentry
*dentry
,
1421 if (flags
& (LOOKUP_CREATE
| LOOKUP_RENAME_TARGET
))
1423 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONEG
)
1425 return !nfs_check_verifier(dir
, dentry
, flags
& LOOKUP_RCU
);
1429 nfs_lookup_revalidate_done(struct inode
*dir
, struct dentry
*dentry
,
1430 struct inode
*inode
, int error
)
1434 dfprintk(LOOKUPCACHE
, "NFS: %s(%pd2) is valid\n",
1438 nfs_mark_for_revalidate(dir
);
1439 if (inode
&& S_ISDIR(inode
->i_mode
)) {
1440 /* Purge readdir caches. */
1441 nfs_zap_caches(inode
);
1443 * We can't d_drop the root of a disconnected tree:
1444 * its d_hash is on the s_anon list and d_drop() would hide
1445 * it from shrink_dcache_for_unmount(), leading to busy
1446 * inodes on unmount and further oopses.
1448 if (IS_ROOT(dentry
))
1451 dfprintk(LOOKUPCACHE
, "NFS: %s(%pd2) is invalid\n",
1455 dfprintk(LOOKUPCACHE
, "NFS: %s(%pd2) lookup returned error %d\n",
1456 __func__
, dentry
, error
);
1461 nfs_lookup_revalidate_negative(struct inode
*dir
, struct dentry
*dentry
,
1465 if (nfs_neg_need_reval(dir
, dentry
, flags
)) {
1466 if (flags
& LOOKUP_RCU
)
1470 return nfs_lookup_revalidate_done(dir
, dentry
, NULL
, ret
);
1474 nfs_lookup_revalidate_delegated(struct inode
*dir
, struct dentry
*dentry
,
1475 struct inode
*inode
)
1477 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1478 return nfs_lookup_revalidate_done(dir
, dentry
, inode
, 1);
1482 nfs_lookup_revalidate_dentry(struct inode
*dir
, struct dentry
*dentry
,
1483 struct inode
*inode
)
1485 struct nfs_fh
*fhandle
;
1486 struct nfs_fattr
*fattr
;
1487 struct nfs4_label
*label
;
1488 unsigned long dir_verifier
;
1492 fhandle
= nfs_alloc_fhandle();
1493 fattr
= nfs_alloc_fattr();
1494 label
= nfs4_label_alloc(NFS_SERVER(inode
), GFP_KERNEL
);
1495 if (fhandle
== NULL
|| fattr
== NULL
|| IS_ERR(label
))
1498 dir_verifier
= nfs_save_change_attribute(dir
);
1499 ret
= NFS_PROTO(dir
)->lookup(dir
, dentry
, fhandle
, fattr
, label
);
1507 if (NFS_SERVER(inode
)->flags
& NFS_MOUNT_SOFTREVAL
)
1513 if (nfs_compare_fh(NFS_FH(inode
), fhandle
))
1515 if (nfs_refresh_inode(inode
, fattr
) < 0)
1518 nfs_setsecurity(inode
, fattr
, label
);
1519 nfs_set_verifier(dentry
, dir_verifier
);
1521 /* set a readdirplus hint that we had a cache miss */
1522 nfs_force_use_readdirplus(dir
);
1525 nfs_free_fattr(fattr
);
1526 nfs_free_fhandle(fhandle
);
1527 nfs4_label_free(label
);
1528 return nfs_lookup_revalidate_done(dir
, dentry
, inode
, ret
);
1532 * This is called every time the dcache has a lookup hit,
1533 * and we should check whether we can really trust that
1536 * NOTE! The hit can be a negative hit too, don't assume
1539 * If the parent directory is seen to have changed, we throw out the
1540 * cached dentry and do a new lookup.
1543 nfs_do_lookup_revalidate(struct inode
*dir
, struct dentry
*dentry
,
1546 struct inode
*inode
;
1549 nfs_inc_stats(dir
, NFSIOS_DENTRYREVALIDATE
);
1550 inode
= d_inode(dentry
);
1553 return nfs_lookup_revalidate_negative(dir
, dentry
, flags
);
1555 if (is_bad_inode(inode
)) {
1556 dfprintk(LOOKUPCACHE
, "%s: %pd2 has dud inode\n",
1561 if (nfs_verifier_is_delegated(dentry
))
1562 return nfs_lookup_revalidate_delegated(dir
, dentry
, inode
);
1564 /* Force a full look up iff the parent directory has changed */
1565 if (!(flags
& (LOOKUP_EXCL
| LOOKUP_REVAL
)) &&
1566 nfs_check_verifier(dir
, dentry
, flags
& LOOKUP_RCU
)) {
1567 error
= nfs_lookup_verify_inode(inode
, flags
);
1569 if (error
== -ESTALE
)
1570 nfs_zap_caches(dir
);
1573 nfs_advise_use_readdirplus(dir
);
1577 if (flags
& LOOKUP_RCU
)
1580 if (NFS_STALE(inode
))
1583 trace_nfs_lookup_revalidate_enter(dir
, dentry
, flags
);
1584 error
= nfs_lookup_revalidate_dentry(dir
, dentry
, inode
);
1585 trace_nfs_lookup_revalidate_exit(dir
, dentry
, flags
, error
);
1588 return nfs_lookup_revalidate_done(dir
, dentry
, inode
, 1);
1590 if (flags
& LOOKUP_RCU
)
1592 return nfs_lookup_revalidate_done(dir
, dentry
, inode
, 0);
1596 __nfs_lookup_revalidate(struct dentry
*dentry
, unsigned int flags
,
1597 int (*reval
)(struct inode
*, struct dentry
*, unsigned int))
1599 struct dentry
*parent
;
1603 if (flags
& LOOKUP_RCU
) {
1604 parent
= READ_ONCE(dentry
->d_parent
);
1605 dir
= d_inode_rcu(parent
);
1608 ret
= reval(dir
, dentry
, flags
);
1609 if (parent
!= READ_ONCE(dentry
->d_parent
))
1612 parent
= dget_parent(dentry
);
1613 ret
= reval(d_inode(parent
), dentry
, flags
);
1619 static int nfs_lookup_revalidate(struct dentry
*dentry
, unsigned int flags
)
1621 return __nfs_lookup_revalidate(dentry
, flags
, nfs_do_lookup_revalidate
);
1625 * A weaker form of d_revalidate for revalidating just the d_inode(dentry)
1626 * when we don't really care about the dentry name. This is called when a
1627 * pathwalk ends on a dentry that was not found via a normal lookup in the
1628 * parent dir (e.g.: ".", "..", procfs symlinks or mountpoint traversals).
1630 * In this situation, we just want to verify that the inode itself is OK
1631 * since the dentry might have changed on the server.
1633 static int nfs_weak_revalidate(struct dentry
*dentry
, unsigned int flags
)
1635 struct inode
*inode
= d_inode(dentry
);
1639 * I believe we can only get a negative dentry here in the case of a
1640 * procfs-style symlink. Just assume it's correct for now, but we may
1641 * eventually need to do something more here.
1644 dfprintk(LOOKUPCACHE
, "%s: %pd2 has negative inode\n",
1649 if (is_bad_inode(inode
)) {
1650 dfprintk(LOOKUPCACHE
, "%s: %pd2 has dud inode\n",
1655 error
= nfs_lookup_verify_inode(inode
, flags
);
1656 dfprintk(LOOKUPCACHE
, "NFS: %s: inode %lu is %s\n",
1657 __func__
, inode
->i_ino
, error
? "invalid" : "valid");
1662 * This is called from dput() when d_count is going to 0.
1664 static int nfs_dentry_delete(const struct dentry
*dentry
)
1666 dfprintk(VFS
, "NFS: dentry_delete(%pd2, %x)\n",
1667 dentry
, dentry
->d_flags
);
1669 /* Unhash any dentry with a stale inode */
1670 if (d_really_is_positive(dentry
) && NFS_STALE(d_inode(dentry
)))
1673 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1674 /* Unhash it, so that ->d_iput() would be called */
1677 if (!(dentry
->d_sb
->s_flags
& SB_ACTIVE
)) {
1678 /* Unhash it, so that ancestors of killed async unlink
1679 * files will be cleaned up during umount */
1686 /* Ensure that we revalidate inode->i_nlink */
1687 static void nfs_drop_nlink(struct inode
*inode
)
1689 spin_lock(&inode
->i_lock
);
1690 /* drop the inode if we're reasonably sure this is the last link */
1691 if (inode
->i_nlink
> 0)
1693 NFS_I(inode
)->attr_gencount
= nfs_inc_attr_generation_counter();
1694 NFS_I(inode
)->cache_validity
|= NFS_INO_INVALID_CHANGE
1695 | NFS_INO_INVALID_CTIME
1696 | NFS_INO_INVALID_OTHER
1697 | NFS_INO_REVAL_FORCED
;
1698 spin_unlock(&inode
->i_lock
);
1702 * Called when the dentry loses inode.
1703 * We use it to clean up silly-renamed files.
1705 static void nfs_dentry_iput(struct dentry
*dentry
, struct inode
*inode
)
1707 if (S_ISDIR(inode
->i_mode
))
1708 /* drop any readdir cache as it could easily be old */
1709 NFS_I(inode
)->cache_validity
|= NFS_INO_INVALID_DATA
;
1711 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1712 nfs_complete_unlink(dentry
, inode
);
1713 nfs_drop_nlink(inode
);
1718 static void nfs_d_release(struct dentry
*dentry
)
1720 /* free cached devname value, if it survived that far */
1721 if (unlikely(dentry
->d_fsdata
)) {
1722 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
)
1725 kfree(dentry
->d_fsdata
);
1729 const struct dentry_operations nfs_dentry_operations
= {
1730 .d_revalidate
= nfs_lookup_revalidate
,
1731 .d_weak_revalidate
= nfs_weak_revalidate
,
1732 .d_delete
= nfs_dentry_delete
,
1733 .d_iput
= nfs_dentry_iput
,
1734 .d_automount
= nfs_d_automount
,
1735 .d_release
= nfs_d_release
,
1737 EXPORT_SYMBOL_GPL(nfs_dentry_operations
);
1739 struct dentry
*nfs_lookup(struct inode
*dir
, struct dentry
* dentry
, unsigned int flags
)
1742 struct inode
*inode
= NULL
;
1743 struct nfs_fh
*fhandle
= NULL
;
1744 struct nfs_fattr
*fattr
= NULL
;
1745 struct nfs4_label
*label
= NULL
;
1746 unsigned long dir_verifier
;
1749 dfprintk(VFS
, "NFS: lookup(%pd2)\n", dentry
);
1750 nfs_inc_stats(dir
, NFSIOS_VFSLOOKUP
);
1752 if (unlikely(dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
))
1753 return ERR_PTR(-ENAMETOOLONG
);
1756 * If we're doing an exclusive create, optimize away the lookup
1757 * but don't hash the dentry.
1759 if (nfs_is_exclusive_create(dir
, flags
) || flags
& LOOKUP_RENAME_TARGET
)
1762 res
= ERR_PTR(-ENOMEM
);
1763 fhandle
= nfs_alloc_fhandle();
1764 fattr
= nfs_alloc_fattr();
1765 if (fhandle
== NULL
|| fattr
== NULL
)
1768 label
= nfs4_label_alloc(NFS_SERVER(dir
), GFP_NOWAIT
);
1772 dir_verifier
= nfs_save_change_attribute(dir
);
1773 trace_nfs_lookup_enter(dir
, dentry
, flags
);
1774 error
= NFS_PROTO(dir
)->lookup(dir
, dentry
, fhandle
, fattr
, label
);
1775 if (error
== -ENOENT
)
1778 res
= ERR_PTR(error
);
1781 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
, label
);
1782 res
= ERR_CAST(inode
);
1786 /* Notify readdir to use READDIRPLUS */
1787 nfs_force_use_readdirplus(dir
);
1790 res
= d_splice_alias(inode
, dentry
);
1796 nfs_set_verifier(dentry
, dir_verifier
);
1798 trace_nfs_lookup_exit(dir
, dentry
, flags
, error
);
1799 nfs4_label_free(label
);
1801 nfs_free_fattr(fattr
);
1802 nfs_free_fhandle(fhandle
);
1805 EXPORT_SYMBOL_GPL(nfs_lookup
);
1807 #if IS_ENABLED(CONFIG_NFS_V4)
1808 static int nfs4_lookup_revalidate(struct dentry
*, unsigned int);
1810 const struct dentry_operations nfs4_dentry_operations
= {
1811 .d_revalidate
= nfs4_lookup_revalidate
,
1812 .d_weak_revalidate
= nfs_weak_revalidate
,
1813 .d_delete
= nfs_dentry_delete
,
1814 .d_iput
= nfs_dentry_iput
,
1815 .d_automount
= nfs_d_automount
,
1816 .d_release
= nfs_d_release
,
1818 EXPORT_SYMBOL_GPL(nfs4_dentry_operations
);
1820 static fmode_t
flags_to_mode(int flags
)
1822 fmode_t res
= (__force fmode_t
)flags
& FMODE_EXEC
;
1823 if ((flags
& O_ACCMODE
) != O_WRONLY
)
1825 if ((flags
& O_ACCMODE
) != O_RDONLY
)
1830 static struct nfs_open_context
*create_nfs_open_context(struct dentry
*dentry
, int open_flags
, struct file
*filp
)
1832 return alloc_nfs_open_context(dentry
, flags_to_mode(open_flags
), filp
);
1835 static int do_open(struct inode
*inode
, struct file
*filp
)
1837 nfs_fscache_open_file(inode
, filp
);
1841 static int nfs_finish_open(struct nfs_open_context
*ctx
,
1842 struct dentry
*dentry
,
1843 struct file
*file
, unsigned open_flags
)
1847 err
= finish_open(file
, dentry
, do_open
);
1850 if (S_ISREG(file
->f_path
.dentry
->d_inode
->i_mode
))
1851 nfs_file_set_open_context(file
, ctx
);
1858 int nfs_atomic_open(struct inode
*dir
, struct dentry
*dentry
,
1859 struct file
*file
, unsigned open_flags
,
1862 DECLARE_WAIT_QUEUE_HEAD_ONSTACK(wq
);
1863 struct nfs_open_context
*ctx
;
1865 struct iattr attr
= { .ia_valid
= ATTR_OPEN
};
1866 struct inode
*inode
;
1867 unsigned int lookup_flags
= 0;
1868 bool switched
= false;
1872 /* Expect a negative dentry */
1873 BUG_ON(d_inode(dentry
));
1875 dfprintk(VFS
, "NFS: atomic_open(%s/%lu), %pd\n",
1876 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
1878 err
= nfs_check_flags(open_flags
);
1882 /* NFS only supports OPEN on regular files */
1883 if ((open_flags
& O_DIRECTORY
)) {
1884 if (!d_in_lookup(dentry
)) {
1886 * Hashed negative dentry with O_DIRECTORY: dentry was
1887 * revalidated and is fine, no need to perform lookup
1892 lookup_flags
= LOOKUP_OPEN
|LOOKUP_DIRECTORY
;
1896 if (dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
)
1897 return -ENAMETOOLONG
;
1899 if (open_flags
& O_CREAT
) {
1900 struct nfs_server
*server
= NFS_SERVER(dir
);
1902 if (!(server
->attr_bitmask
[2] & FATTR4_WORD2_MODE_UMASK
))
1903 mode
&= ~current_umask();
1905 attr
.ia_valid
|= ATTR_MODE
;
1906 attr
.ia_mode
= mode
;
1908 if (open_flags
& O_TRUNC
) {
1909 attr
.ia_valid
|= ATTR_SIZE
;
1913 if (!(open_flags
& O_CREAT
) && !d_in_lookup(dentry
)) {
1916 dentry
= d_alloc_parallel(dentry
->d_parent
,
1917 &dentry
->d_name
, &wq
);
1919 return PTR_ERR(dentry
);
1920 if (unlikely(!d_in_lookup(dentry
)))
1921 return finish_no_open(file
, dentry
);
1924 ctx
= create_nfs_open_context(dentry
, open_flags
, file
);
1929 trace_nfs_atomic_open_enter(dir
, ctx
, open_flags
);
1930 inode
= NFS_PROTO(dir
)->open_context(dir
, ctx
, open_flags
, &attr
, &created
);
1932 file
->f_mode
|= FMODE_CREATED
;
1933 if (IS_ERR(inode
)) {
1934 err
= PTR_ERR(inode
);
1935 trace_nfs_atomic_open_exit(dir
, ctx
, open_flags
, err
);
1936 put_nfs_open_context(ctx
);
1940 d_splice_alias(NULL
, dentry
);
1941 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1947 if (!(open_flags
& O_NOFOLLOW
))
1957 err
= nfs_finish_open(ctx
, ctx
->dentry
, file
, open_flags
);
1958 trace_nfs_atomic_open_exit(dir
, ctx
, open_flags
, err
);
1959 put_nfs_open_context(ctx
);
1961 if (unlikely(switched
)) {
1962 d_lookup_done(dentry
);
1968 res
= nfs_lookup(dir
, dentry
, lookup_flags
);
1970 d_lookup_done(dentry
);
1977 return PTR_ERR(res
);
1978 return finish_no_open(file
, res
);
1980 EXPORT_SYMBOL_GPL(nfs_atomic_open
);
1983 nfs4_do_lookup_revalidate(struct inode
*dir
, struct dentry
*dentry
,
1986 struct inode
*inode
;
1988 if (!(flags
& LOOKUP_OPEN
) || (flags
& LOOKUP_DIRECTORY
))
1990 if (d_mountpoint(dentry
))
1993 inode
= d_inode(dentry
);
1995 /* We can't create new files in nfs_open_revalidate(), so we
1996 * optimize away revalidation of negative dentries.
2001 if (nfs_verifier_is_delegated(dentry
))
2002 return nfs_lookup_revalidate_delegated(dir
, dentry
, inode
);
2004 /* NFS only supports OPEN on regular files */
2005 if (!S_ISREG(inode
->i_mode
))
2008 /* We cannot do exclusive creation on a positive dentry */
2009 if (flags
& (LOOKUP_EXCL
| LOOKUP_REVAL
))
2012 /* Check if the directory changed */
2013 if (!nfs_check_verifier(dir
, dentry
, flags
& LOOKUP_RCU
))
2016 /* Let f_op->open() actually open (and revalidate) the file */
2019 if (flags
& LOOKUP_RCU
)
2021 return nfs_lookup_revalidate_dentry(dir
, dentry
, inode
);
2024 return nfs_do_lookup_revalidate(dir
, dentry
, flags
);
2027 static int nfs4_lookup_revalidate(struct dentry
*dentry
, unsigned int flags
)
2029 return __nfs_lookup_revalidate(dentry
, flags
,
2030 nfs4_do_lookup_revalidate
);
2033 #endif /* CONFIG_NFSV4 */
2036 nfs_add_or_obtain(struct dentry
*dentry
, struct nfs_fh
*fhandle
,
2037 struct nfs_fattr
*fattr
,
2038 struct nfs4_label
*label
)
2040 struct dentry
*parent
= dget_parent(dentry
);
2041 struct inode
*dir
= d_inode(parent
);
2042 struct inode
*inode
;
2048 if (fhandle
->size
== 0) {
2049 error
= NFS_PROTO(dir
)->lookup(dir
, dentry
, fhandle
, fattr
, NULL
);
2053 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
2054 if (!(fattr
->valid
& NFS_ATTR_FATTR
)) {
2055 struct nfs_server
*server
= NFS_SB(dentry
->d_sb
);
2056 error
= server
->nfs_client
->rpc_ops
->getattr(server
, fhandle
,
2061 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
, label
);
2062 d
= d_splice_alias(inode
, dentry
);
2067 nfs_mark_for_revalidate(dir
);
2071 EXPORT_SYMBOL_GPL(nfs_add_or_obtain
);
2074 * Code common to create, mkdir, and mknod.
2076 int nfs_instantiate(struct dentry
*dentry
, struct nfs_fh
*fhandle
,
2077 struct nfs_fattr
*fattr
,
2078 struct nfs4_label
*label
)
2082 d
= nfs_add_or_obtain(dentry
, fhandle
, fattr
, label
);
2086 /* Callers don't care */
2090 EXPORT_SYMBOL_GPL(nfs_instantiate
);
2093 * Following a failed create operation, we drop the dentry rather
2094 * than retain a negative dentry. This avoids a problem in the event
2095 * that the operation succeeded on the server, but an error in the
2096 * reply path made it appear to have failed.
2098 int nfs_create(struct inode
*dir
, struct dentry
*dentry
,
2099 umode_t mode
, bool excl
)
2102 int open_flags
= excl
? O_CREAT
| O_EXCL
: O_CREAT
;
2105 dfprintk(VFS
, "NFS: create(%s/%lu), %pd\n",
2106 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
2108 attr
.ia_mode
= mode
;
2109 attr
.ia_valid
= ATTR_MODE
;
2111 trace_nfs_create_enter(dir
, dentry
, open_flags
);
2112 error
= NFS_PROTO(dir
)->create(dir
, dentry
, &attr
, open_flags
);
2113 trace_nfs_create_exit(dir
, dentry
, open_flags
, error
);
2121 EXPORT_SYMBOL_GPL(nfs_create
);
2124 * See comments for nfs_proc_create regarding failed operations.
2127 nfs_mknod(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
, dev_t rdev
)
2132 dfprintk(VFS
, "NFS: mknod(%s/%lu), %pd\n",
2133 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
2135 attr
.ia_mode
= mode
;
2136 attr
.ia_valid
= ATTR_MODE
;
2138 trace_nfs_mknod_enter(dir
, dentry
);
2139 status
= NFS_PROTO(dir
)->mknod(dir
, dentry
, &attr
, rdev
);
2140 trace_nfs_mknod_exit(dir
, dentry
, status
);
2148 EXPORT_SYMBOL_GPL(nfs_mknod
);
2151 * See comments for nfs_proc_create regarding failed operations.
2153 int nfs_mkdir(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
)
2158 dfprintk(VFS
, "NFS: mkdir(%s/%lu), %pd\n",
2159 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
2161 attr
.ia_valid
= ATTR_MODE
;
2162 attr
.ia_mode
= mode
| S_IFDIR
;
2164 trace_nfs_mkdir_enter(dir
, dentry
);
2165 error
= NFS_PROTO(dir
)->mkdir(dir
, dentry
, &attr
);
2166 trace_nfs_mkdir_exit(dir
, dentry
, error
);
2174 EXPORT_SYMBOL_GPL(nfs_mkdir
);
2176 static void nfs_dentry_handle_enoent(struct dentry
*dentry
)
2178 if (simple_positive(dentry
))
2182 int nfs_rmdir(struct inode
*dir
, struct dentry
*dentry
)
2186 dfprintk(VFS
, "NFS: rmdir(%s/%lu), %pd\n",
2187 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
);
2189 trace_nfs_rmdir_enter(dir
, dentry
);
2190 if (d_really_is_positive(dentry
)) {
2191 down_write(&NFS_I(d_inode(dentry
))->rmdir_sem
);
2192 error
= NFS_PROTO(dir
)->rmdir(dir
, &dentry
->d_name
);
2193 /* Ensure the VFS deletes this inode */
2196 clear_nlink(d_inode(dentry
));
2199 nfs_dentry_handle_enoent(dentry
);
2201 up_write(&NFS_I(d_inode(dentry
))->rmdir_sem
);
2203 error
= NFS_PROTO(dir
)->rmdir(dir
, &dentry
->d_name
);
2204 trace_nfs_rmdir_exit(dir
, dentry
, error
);
2208 EXPORT_SYMBOL_GPL(nfs_rmdir
);
2211 * Remove a file after making sure there are no pending writes,
2212 * and after checking that the file has only one user.
2214 * We invalidate the attribute cache and free the inode prior to the operation
2215 * to avoid possible races if the server reuses the inode.
2217 static int nfs_safe_remove(struct dentry
*dentry
)
2219 struct inode
*dir
= d_inode(dentry
->d_parent
);
2220 struct inode
*inode
= d_inode(dentry
);
2223 dfprintk(VFS
, "NFS: safe_remove(%pd2)\n", dentry
);
2225 /* If the dentry was sillyrenamed, we simply call d_delete() */
2226 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
2231 trace_nfs_remove_enter(dir
, dentry
);
2232 if (inode
!= NULL
) {
2233 error
= NFS_PROTO(dir
)->remove(dir
, dentry
);
2235 nfs_drop_nlink(inode
);
2237 error
= NFS_PROTO(dir
)->remove(dir
, dentry
);
2238 if (error
== -ENOENT
)
2239 nfs_dentry_handle_enoent(dentry
);
2240 trace_nfs_remove_exit(dir
, dentry
, error
);
2245 /* We do silly rename. In case sillyrename() returns -EBUSY, the inode
2246 * belongs to an active ".nfs..." file and we return -EBUSY.
2248 * If sillyrename() returns 0, we do nothing, otherwise we unlink.
2250 int nfs_unlink(struct inode
*dir
, struct dentry
*dentry
)
2253 int need_rehash
= 0;
2255 dfprintk(VFS
, "NFS: unlink(%s/%lu, %pd)\n", dir
->i_sb
->s_id
,
2256 dir
->i_ino
, dentry
);
2258 trace_nfs_unlink_enter(dir
, dentry
);
2259 spin_lock(&dentry
->d_lock
);
2260 if (d_count(dentry
) > 1) {
2261 spin_unlock(&dentry
->d_lock
);
2262 /* Start asynchronous writeout of the inode */
2263 write_inode_now(d_inode(dentry
), 0);
2264 error
= nfs_sillyrename(dir
, dentry
);
2267 if (!d_unhashed(dentry
)) {
2271 spin_unlock(&dentry
->d_lock
);
2272 error
= nfs_safe_remove(dentry
);
2273 if (!error
|| error
== -ENOENT
) {
2274 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
2275 } else if (need_rehash
)
2278 trace_nfs_unlink_exit(dir
, dentry
, error
);
2281 EXPORT_SYMBOL_GPL(nfs_unlink
);
2284 * To create a symbolic link, most file systems instantiate a new inode,
2285 * add a page to it containing the path, then write it out to the disk
2286 * using prepare_write/commit_write.
2288 * Unfortunately the NFS client can't create the in-core inode first
2289 * because it needs a file handle to create an in-core inode (see
2290 * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the
2291 * symlink request has completed on the server.
2293 * So instead we allocate a raw page, copy the symname into it, then do
2294 * the SYMLINK request with the page as the buffer. If it succeeds, we
2295 * now have a new file handle and can instantiate an in-core NFS inode
2296 * and move the raw page into its mapping.
2298 int nfs_symlink(struct inode
*dir
, struct dentry
*dentry
, const char *symname
)
2303 unsigned int pathlen
= strlen(symname
);
2306 dfprintk(VFS
, "NFS: symlink(%s/%lu, %pd, %s)\n", dir
->i_sb
->s_id
,
2307 dir
->i_ino
, dentry
, symname
);
2309 if (pathlen
> PAGE_SIZE
)
2310 return -ENAMETOOLONG
;
2312 attr
.ia_mode
= S_IFLNK
| S_IRWXUGO
;
2313 attr
.ia_valid
= ATTR_MODE
;
2315 page
= alloc_page(GFP_USER
);
2319 kaddr
= page_address(page
);
2320 memcpy(kaddr
, symname
, pathlen
);
2321 if (pathlen
< PAGE_SIZE
)
2322 memset(kaddr
+ pathlen
, 0, PAGE_SIZE
- pathlen
);
2324 trace_nfs_symlink_enter(dir
, dentry
);
2325 error
= NFS_PROTO(dir
)->symlink(dir
, dentry
, page
, pathlen
, &attr
);
2326 trace_nfs_symlink_exit(dir
, dentry
, error
);
2328 dfprintk(VFS
, "NFS: symlink(%s/%lu, %pd, %s) error %d\n",
2329 dir
->i_sb
->s_id
, dir
->i_ino
,
2330 dentry
, symname
, error
);
2337 * No big deal if we can't add this page to the page cache here.
2338 * READLINK will get the missing page from the server if needed.
2340 if (!add_to_page_cache_lru(page
, d_inode(dentry
)->i_mapping
, 0,
2342 SetPageUptodate(page
);
2345 * add_to_page_cache_lru() grabs an extra page refcount.
2346 * Drop it here to avoid leaking this page later.
2354 EXPORT_SYMBOL_GPL(nfs_symlink
);
2357 nfs_link(struct dentry
*old_dentry
, struct inode
*dir
, struct dentry
*dentry
)
2359 struct inode
*inode
= d_inode(old_dentry
);
2362 dfprintk(VFS
, "NFS: link(%pd2 -> %pd2)\n",
2363 old_dentry
, dentry
);
2365 trace_nfs_link_enter(inode
, dir
, dentry
);
2367 error
= NFS_PROTO(dir
)->link(inode
, dir
, &dentry
->d_name
);
2370 d_add(dentry
, inode
);
2372 trace_nfs_link_exit(inode
, dir
, dentry
, error
);
2375 EXPORT_SYMBOL_GPL(nfs_link
);
2379 * FIXME: Some nfsds, like the Linux user space nfsd, may generate a
2380 * different file handle for the same inode after a rename (e.g. when
2381 * moving to a different directory). A fail-safe method to do so would
2382 * be to look up old_dir/old_name, create a link to new_dir/new_name and
2383 * rename the old file using the sillyrename stuff. This way, the original
2384 * file in old_dir will go away when the last process iput()s the inode.
2388 * It actually works quite well. One needs to have the possibility for
2389 * at least one ".nfs..." file in each directory the file ever gets
2390 * moved or linked to which happens automagically with the new
2391 * implementation that only depends on the dcache stuff instead of
2392 * using the inode layer
2394 * Unfortunately, things are a little more complicated than indicated
2395 * above. For a cross-directory move, we want to make sure we can get
2396 * rid of the old inode after the operation. This means there must be
2397 * no pending writes (if it's a file), and the use count must be 1.
2398 * If these conditions are met, we can drop the dentries before doing
2401 int nfs_rename(struct inode
*old_dir
, struct dentry
*old_dentry
,
2402 struct inode
*new_dir
, struct dentry
*new_dentry
,
2405 struct inode
*old_inode
= d_inode(old_dentry
);
2406 struct inode
*new_inode
= d_inode(new_dentry
);
2407 struct dentry
*dentry
= NULL
, *rehash
= NULL
;
2408 struct rpc_task
*task
;
2414 dfprintk(VFS
, "NFS: rename(%pd2 -> %pd2, ct=%d)\n",
2415 old_dentry
, new_dentry
,
2416 d_count(new_dentry
));
2418 trace_nfs_rename_enter(old_dir
, old_dentry
, new_dir
, new_dentry
);
2420 * For non-directories, check whether the target is busy and if so,
2421 * make a copy of the dentry and then do a silly-rename. If the
2422 * silly-rename succeeds, the copied dentry is hashed and becomes
2425 if (new_inode
&& !S_ISDIR(new_inode
->i_mode
)) {
2427 * To prevent any new references to the target during the
2428 * rename, we unhash the dentry in advance.
2430 if (!d_unhashed(new_dentry
)) {
2432 rehash
= new_dentry
;
2435 if (d_count(new_dentry
) > 2) {
2438 /* copy the target dentry's name */
2439 dentry
= d_alloc(new_dentry
->d_parent
,
2440 &new_dentry
->d_name
);
2444 /* silly-rename the existing target ... */
2445 err
= nfs_sillyrename(new_dir
, new_dentry
);
2449 new_dentry
= dentry
;
2455 task
= nfs_async_rename(old_dir
, new_dir
, old_dentry
, new_dentry
, NULL
);
2457 error
= PTR_ERR(task
);
2461 error
= rpc_wait_for_completion_task(task
);
2463 ((struct nfs_renamedata
*)task
->tk_calldata
)->cancelled
= 1;
2464 /* Paired with the atomic_dec_and_test() barrier in rpc_do_put_task() */
2467 error
= task
->tk_status
;
2469 /* Ensure the inode attributes are revalidated */
2471 spin_lock(&old_inode
->i_lock
);
2472 NFS_I(old_inode
)->attr_gencount
= nfs_inc_attr_generation_counter();
2473 NFS_I(old_inode
)->cache_validity
|= NFS_INO_INVALID_CHANGE
2474 | NFS_INO_INVALID_CTIME
2475 | NFS_INO_REVAL_FORCED
;
2476 spin_unlock(&old_inode
->i_lock
);
2481 trace_nfs_rename_exit(old_dir
, old_dentry
,
2482 new_dir
, new_dentry
, error
);
2484 if (new_inode
!= NULL
)
2485 nfs_drop_nlink(new_inode
);
2487 * The d_move() should be here instead of in an async RPC completion
2488 * handler because we need the proper locks to move the dentry. If
2489 * we're interrupted by a signal, the async RPC completion handler
2490 * should mark the directories for revalidation.
2492 d_move(old_dentry
, new_dentry
);
2493 nfs_set_verifier(old_dentry
,
2494 nfs_save_change_attribute(new_dir
));
2495 } else if (error
== -ENOENT
)
2496 nfs_dentry_handle_enoent(old_dentry
);
2498 /* new dentry created? */
2503 EXPORT_SYMBOL_GPL(nfs_rename
);
2505 static DEFINE_SPINLOCK(nfs_access_lru_lock
);
2506 static LIST_HEAD(nfs_access_lru_list
);
2507 static atomic_long_t nfs_access_nr_entries
;
2509 static unsigned long nfs_access_max_cachesize
= 4*1024*1024;
2510 module_param(nfs_access_max_cachesize
, ulong
, 0644);
2511 MODULE_PARM_DESC(nfs_access_max_cachesize
, "NFS access maximum total cache length");
2513 static void nfs_access_free_entry(struct nfs_access_entry
*entry
)
2515 put_cred(entry
->cred
);
2516 kfree_rcu(entry
, rcu_head
);
2517 smp_mb__before_atomic();
2518 atomic_long_dec(&nfs_access_nr_entries
);
2519 smp_mb__after_atomic();
2522 static void nfs_access_free_list(struct list_head
*head
)
2524 struct nfs_access_entry
*cache
;
2526 while (!list_empty(head
)) {
2527 cache
= list_entry(head
->next
, struct nfs_access_entry
, lru
);
2528 list_del(&cache
->lru
);
2529 nfs_access_free_entry(cache
);
2533 static unsigned long
2534 nfs_do_access_cache_scan(unsigned int nr_to_scan
)
2537 struct nfs_inode
*nfsi
, *next
;
2538 struct nfs_access_entry
*cache
;
2541 spin_lock(&nfs_access_lru_lock
);
2542 list_for_each_entry_safe(nfsi
, next
, &nfs_access_lru_list
, access_cache_inode_lru
) {
2543 struct inode
*inode
;
2545 if (nr_to_scan
-- == 0)
2547 inode
= &nfsi
->vfs_inode
;
2548 spin_lock(&inode
->i_lock
);
2549 if (list_empty(&nfsi
->access_cache_entry_lru
))
2550 goto remove_lru_entry
;
2551 cache
= list_entry(nfsi
->access_cache_entry_lru
.next
,
2552 struct nfs_access_entry
, lru
);
2553 list_move(&cache
->lru
, &head
);
2554 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
2556 if (!list_empty(&nfsi
->access_cache_entry_lru
))
2557 list_move_tail(&nfsi
->access_cache_inode_lru
,
2558 &nfs_access_lru_list
);
2561 list_del_init(&nfsi
->access_cache_inode_lru
);
2562 smp_mb__before_atomic();
2563 clear_bit(NFS_INO_ACL_LRU_SET
, &nfsi
->flags
);
2564 smp_mb__after_atomic();
2566 spin_unlock(&inode
->i_lock
);
2568 spin_unlock(&nfs_access_lru_lock
);
2569 nfs_access_free_list(&head
);
2574 nfs_access_cache_scan(struct shrinker
*shrink
, struct shrink_control
*sc
)
2576 int nr_to_scan
= sc
->nr_to_scan
;
2577 gfp_t gfp_mask
= sc
->gfp_mask
;
2579 if ((gfp_mask
& GFP_KERNEL
) != GFP_KERNEL
)
2581 return nfs_do_access_cache_scan(nr_to_scan
);
2586 nfs_access_cache_count(struct shrinker
*shrink
, struct shrink_control
*sc
)
2588 return vfs_pressure_ratio(atomic_long_read(&nfs_access_nr_entries
));
2592 nfs_access_cache_enforce_limit(void)
2594 long nr_entries
= atomic_long_read(&nfs_access_nr_entries
);
2596 unsigned int nr_to_scan
;
2598 if (nr_entries
< 0 || nr_entries
<= nfs_access_max_cachesize
)
2601 diff
= nr_entries
- nfs_access_max_cachesize
;
2602 if (diff
< nr_to_scan
)
2604 nfs_do_access_cache_scan(nr_to_scan
);
2607 static void __nfs_access_zap_cache(struct nfs_inode
*nfsi
, struct list_head
*head
)
2609 struct rb_root
*root_node
= &nfsi
->access_cache
;
2611 struct nfs_access_entry
*entry
;
2613 /* Unhook entries from the cache */
2614 while ((n
= rb_first(root_node
)) != NULL
) {
2615 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
2616 rb_erase(n
, root_node
);
2617 list_move(&entry
->lru
, head
);
2619 nfsi
->cache_validity
&= ~NFS_INO_INVALID_ACCESS
;
2622 void nfs_access_zap_cache(struct inode
*inode
)
2626 if (test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
) == 0)
2628 /* Remove from global LRU init */
2629 spin_lock(&nfs_access_lru_lock
);
2630 if (test_and_clear_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
2631 list_del_init(&NFS_I(inode
)->access_cache_inode_lru
);
2633 spin_lock(&inode
->i_lock
);
2634 __nfs_access_zap_cache(NFS_I(inode
), &head
);
2635 spin_unlock(&inode
->i_lock
);
2636 spin_unlock(&nfs_access_lru_lock
);
2637 nfs_access_free_list(&head
);
2639 EXPORT_SYMBOL_GPL(nfs_access_zap_cache
);
2641 static struct nfs_access_entry
*nfs_access_search_rbtree(struct inode
*inode
, const struct cred
*cred
)
2643 struct rb_node
*n
= NFS_I(inode
)->access_cache
.rb_node
;
2646 struct nfs_access_entry
*entry
=
2647 rb_entry(n
, struct nfs_access_entry
, rb_node
);
2648 int cmp
= cred_fscmp(cred
, entry
->cred
);
2660 static int nfs_access_get_cached_locked(struct inode
*inode
, const struct cred
*cred
, struct nfs_access_entry
*res
, bool may_block
)
2662 struct nfs_inode
*nfsi
= NFS_I(inode
);
2663 struct nfs_access_entry
*cache
;
2667 spin_lock(&inode
->i_lock
);
2669 if (nfsi
->cache_validity
& NFS_INO_INVALID_ACCESS
)
2671 cache
= nfs_access_search_rbtree(inode
, cred
);
2675 /* Found an entry, is our attribute cache valid? */
2676 if (!nfs_check_cache_invalid(inode
, NFS_INO_INVALID_ACCESS
))
2683 spin_unlock(&inode
->i_lock
);
2684 err
= __nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
2687 spin_lock(&inode
->i_lock
);
2690 res
->cred
= cache
->cred
;
2691 res
->mask
= cache
->mask
;
2692 list_move_tail(&cache
->lru
, &nfsi
->access_cache_entry_lru
);
2695 spin_unlock(&inode
->i_lock
);
2698 spin_unlock(&inode
->i_lock
);
2699 nfs_access_zap_cache(inode
);
2703 static int nfs_access_get_cached_rcu(struct inode
*inode
, const struct cred
*cred
, struct nfs_access_entry
*res
)
2705 /* Only check the most recently returned cache entry,
2706 * but do it without locking.
2708 struct nfs_inode
*nfsi
= NFS_I(inode
);
2709 struct nfs_access_entry
*cache
;
2711 struct list_head
*lh
;
2714 if (nfsi
->cache_validity
& NFS_INO_INVALID_ACCESS
)
2716 lh
= rcu_dereference(list_tail_rcu(&nfsi
->access_cache_entry_lru
));
2717 cache
= list_entry(lh
, struct nfs_access_entry
, lru
);
2718 if (lh
== &nfsi
->access_cache_entry_lru
||
2719 cred_fscmp(cred
, cache
->cred
) != 0)
2723 if (nfs_check_cache_invalid(inode
, NFS_INO_INVALID_ACCESS
))
2725 res
->cred
= cache
->cred
;
2726 res
->mask
= cache
->mask
;
2733 int nfs_access_get_cached(struct inode
*inode
, const struct cred
*cred
, struct
2734 nfs_access_entry
*res
, bool may_block
)
2738 status
= nfs_access_get_cached_rcu(inode
, cred
, res
);
2740 status
= nfs_access_get_cached_locked(inode
, cred
, res
,
2745 EXPORT_SYMBOL_GPL(nfs_access_get_cached
);
2747 static void nfs_access_add_rbtree(struct inode
*inode
, struct nfs_access_entry
*set
)
2749 struct nfs_inode
*nfsi
= NFS_I(inode
);
2750 struct rb_root
*root_node
= &nfsi
->access_cache
;
2751 struct rb_node
**p
= &root_node
->rb_node
;
2752 struct rb_node
*parent
= NULL
;
2753 struct nfs_access_entry
*entry
;
2756 spin_lock(&inode
->i_lock
);
2757 while (*p
!= NULL
) {
2759 entry
= rb_entry(parent
, struct nfs_access_entry
, rb_node
);
2760 cmp
= cred_fscmp(set
->cred
, entry
->cred
);
2763 p
= &parent
->rb_left
;
2765 p
= &parent
->rb_right
;
2769 rb_link_node(&set
->rb_node
, parent
, p
);
2770 rb_insert_color(&set
->rb_node
, root_node
);
2771 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2772 spin_unlock(&inode
->i_lock
);
2775 rb_replace_node(parent
, &set
->rb_node
, root_node
);
2776 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2777 list_del(&entry
->lru
);
2778 spin_unlock(&inode
->i_lock
);
2779 nfs_access_free_entry(entry
);
2782 void nfs_access_add_cache(struct inode
*inode
, struct nfs_access_entry
*set
)
2784 struct nfs_access_entry
*cache
= kmalloc(sizeof(*cache
), GFP_KERNEL
);
2787 RB_CLEAR_NODE(&cache
->rb_node
);
2788 cache
->cred
= get_cred(set
->cred
);
2789 cache
->mask
= set
->mask
;
2791 /* The above field assignments must be visible
2792 * before this item appears on the lru. We cannot easily
2793 * use rcu_assign_pointer, so just force the memory barrier.
2796 nfs_access_add_rbtree(inode
, cache
);
2798 /* Update accounting */
2799 smp_mb__before_atomic();
2800 atomic_long_inc(&nfs_access_nr_entries
);
2801 smp_mb__after_atomic();
2803 /* Add inode to global LRU list */
2804 if (!test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
)) {
2805 spin_lock(&nfs_access_lru_lock
);
2806 if (!test_and_set_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
2807 list_add_tail(&NFS_I(inode
)->access_cache_inode_lru
,
2808 &nfs_access_lru_list
);
2809 spin_unlock(&nfs_access_lru_lock
);
2811 nfs_access_cache_enforce_limit();
2813 EXPORT_SYMBOL_GPL(nfs_access_add_cache
);
2815 #define NFS_MAY_READ (NFS_ACCESS_READ)
2816 #define NFS_MAY_WRITE (NFS_ACCESS_MODIFY | \
2817 NFS_ACCESS_EXTEND | \
2819 #define NFS_FILE_MAY_WRITE (NFS_ACCESS_MODIFY | \
2821 #define NFS_DIR_MAY_WRITE NFS_MAY_WRITE
2822 #define NFS_MAY_LOOKUP (NFS_ACCESS_LOOKUP)
2823 #define NFS_MAY_EXECUTE (NFS_ACCESS_EXECUTE)
2825 nfs_access_calc_mask(u32 access_result
, umode_t umode
)
2829 if (access_result
& NFS_MAY_READ
)
2831 if (S_ISDIR(umode
)) {
2832 if ((access_result
& NFS_DIR_MAY_WRITE
) == NFS_DIR_MAY_WRITE
)
2834 if ((access_result
& NFS_MAY_LOOKUP
) == NFS_MAY_LOOKUP
)
2836 } else if (S_ISREG(umode
)) {
2837 if ((access_result
& NFS_FILE_MAY_WRITE
) == NFS_FILE_MAY_WRITE
)
2839 if ((access_result
& NFS_MAY_EXECUTE
) == NFS_MAY_EXECUTE
)
2841 } else if (access_result
& NFS_MAY_WRITE
)
2846 void nfs_access_set_mask(struct nfs_access_entry
*entry
, u32 access_result
)
2848 entry
->mask
= access_result
;
2850 EXPORT_SYMBOL_GPL(nfs_access_set_mask
);
2852 static int nfs_do_access(struct inode
*inode
, const struct cred
*cred
, int mask
)
2854 struct nfs_access_entry cache
;
2855 bool may_block
= (mask
& MAY_NOT_BLOCK
) == 0;
2856 int cache_mask
= -1;
2859 trace_nfs_access_enter(inode
);
2861 status
= nfs_access_get_cached(inode
, cred
, &cache
, may_block
);
2870 * Determine which access bits we want to ask for...
2872 cache
.mask
= NFS_ACCESS_READ
| NFS_ACCESS_MODIFY
| NFS_ACCESS_EXTEND
;
2873 if (nfs_server_capable(inode
, NFS_CAP_XATTR
)) {
2874 cache
.mask
|= NFS_ACCESS_XAREAD
| NFS_ACCESS_XAWRITE
|
2877 if (S_ISDIR(inode
->i_mode
))
2878 cache
.mask
|= NFS_ACCESS_DELETE
| NFS_ACCESS_LOOKUP
;
2880 cache
.mask
|= NFS_ACCESS_EXECUTE
;
2882 status
= NFS_PROTO(inode
)->access(inode
, &cache
);
2884 if (status
== -ESTALE
) {
2885 if (!S_ISDIR(inode
->i_mode
))
2886 nfs_set_inode_stale(inode
);
2888 nfs_zap_caches(inode
);
2892 nfs_access_add_cache(inode
, &cache
);
2894 cache_mask
= nfs_access_calc_mask(cache
.mask
, inode
->i_mode
);
2895 if ((mask
& ~cache_mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) != 0)
2898 trace_nfs_access_exit(inode
, mask
, cache_mask
, status
);
2902 static int nfs_open_permission_mask(int openflags
)
2906 if (openflags
& __FMODE_EXEC
) {
2907 /* ONLY check exec rights */
2910 if ((openflags
& O_ACCMODE
) != O_WRONLY
)
2912 if ((openflags
& O_ACCMODE
) != O_RDONLY
)
2919 int nfs_may_open(struct inode
*inode
, const struct cred
*cred
, int openflags
)
2921 return nfs_do_access(inode
, cred
, nfs_open_permission_mask(openflags
));
2923 EXPORT_SYMBOL_GPL(nfs_may_open
);
2925 static int nfs_execute_ok(struct inode
*inode
, int mask
)
2927 struct nfs_server
*server
= NFS_SERVER(inode
);
2930 if (S_ISDIR(inode
->i_mode
))
2932 if (nfs_check_cache_invalid(inode
, NFS_INO_INVALID_OTHER
)) {
2933 if (mask
& MAY_NOT_BLOCK
)
2935 ret
= __nfs_revalidate_inode(server
, inode
);
2937 if (ret
== 0 && !execute_ok(inode
))
2942 int nfs_permission(struct inode
*inode
, int mask
)
2944 const struct cred
*cred
= current_cred();
2947 nfs_inc_stats(inode
, NFSIOS_VFSACCESS
);
2949 if ((mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) == 0)
2951 /* Is this sys_access() ? */
2952 if (mask
& (MAY_ACCESS
| MAY_CHDIR
))
2955 switch (inode
->i_mode
& S_IFMT
) {
2959 if ((mask
& MAY_OPEN
) &&
2960 nfs_server_capable(inode
, NFS_CAP_ATOMIC_OPEN
))
2965 * Optimize away all write operations, since the server
2966 * will check permissions when we perform the op.
2968 if ((mask
& MAY_WRITE
) && !(mask
& MAY_READ
))
2973 if (!NFS_PROTO(inode
)->access
)
2976 res
= nfs_do_access(inode
, cred
, mask
);
2978 if (!res
&& (mask
& MAY_EXEC
))
2979 res
= nfs_execute_ok(inode
, mask
);
2981 dfprintk(VFS
, "NFS: permission(%s/%lu), mask=0x%x, res=%d\n",
2982 inode
->i_sb
->s_id
, inode
->i_ino
, mask
, res
);
2985 if (mask
& MAY_NOT_BLOCK
)
2988 res
= nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
2990 res
= generic_permission(inode
, mask
);
2993 EXPORT_SYMBOL_GPL(nfs_permission
);
2997 * version-control: t
2998 * kept-new-versions: 5