4 * Copyright (C) 1992 Rick Sladkey
6 * nfs directory handling functions
8 * 10 Apr 1996 Added silly rename for unlink --okir
9 * 28 Sep 1996 Improved directory cache --okir
10 * 23 Aug 1997 Claus Heine claus@momo.math.rwth-aachen.de
11 * Re-implemented silly rename for unlink, newly implemented
12 * silly rename for nfs_rename() following the suggestions
13 * of Olaf Kirch (okir) found in this file.
14 * Following Linus comments on my original hack, this version
15 * depends only on the dcache stuff and doesn't touch the inode
16 * layer (iput() and friends).
17 * 6 Jun 1999 Cache readdir lookups in the page cache. -DaveM
20 #include <linux/time.h>
21 #include <linux/errno.h>
22 #include <linux/stat.h>
23 #include <linux/fcntl.h>
24 #include <linux/string.h>
25 #include <linux/kernel.h>
26 #include <linux/slab.h>
28 #include <linux/sunrpc/clnt.h>
29 #include <linux/nfs_fs.h>
30 #include <linux/nfs_mount.h>
31 #include <linux/pagemap.h>
32 #include <linux/pagevec.h>
33 #include <linux/namei.h>
34 #include <linux/mount.h>
35 #include <linux/sched.h>
38 #include "delegation.h"
43 /* #define NFS_DEBUG_VERBOSE 1 */
45 static int nfs_opendir(struct inode
*, struct file
*);
46 static int nfs_readdir(struct file
*, void *, filldir_t
);
47 static struct dentry
*nfs_lookup(struct inode
*, struct dentry
*, struct nameidata
*);
48 static int nfs_create(struct inode
*, struct dentry
*, int, struct nameidata
*);
49 static int nfs_mkdir(struct inode
*, struct dentry
*, int);
50 static int nfs_rmdir(struct inode
*, struct dentry
*);
51 static int nfs_unlink(struct inode
*, struct dentry
*);
52 static int nfs_symlink(struct inode
*, struct dentry
*, const char *);
53 static int nfs_link(struct dentry
*, struct inode
*, struct dentry
*);
54 static int nfs_mknod(struct inode
*, struct dentry
*, int, dev_t
);
55 static int nfs_rename(struct inode
*, struct dentry
*,
56 struct inode
*, struct dentry
*);
57 static int nfs_fsync_dir(struct file
*, int);
58 static loff_t
nfs_llseek_dir(struct file
*, loff_t
, int);
60 const struct file_operations nfs_dir_operations
= {
61 .llseek
= nfs_llseek_dir
,
62 .read
= generic_read_dir
,
63 .readdir
= nfs_readdir
,
65 .release
= nfs_release
,
66 .fsync
= nfs_fsync_dir
,
69 const struct inode_operations nfs_dir_inode_operations
= {
74 .symlink
= nfs_symlink
,
79 .permission
= nfs_permission
,
80 .getattr
= nfs_getattr
,
81 .setattr
= nfs_setattr
,
85 const struct inode_operations nfs3_dir_inode_operations
= {
90 .symlink
= nfs_symlink
,
95 .permission
= nfs_permission
,
96 .getattr
= nfs_getattr
,
97 .setattr
= nfs_setattr
,
98 .listxattr
= nfs3_listxattr
,
99 .getxattr
= nfs3_getxattr
,
100 .setxattr
= nfs3_setxattr
,
101 .removexattr
= nfs3_removexattr
,
103 #endif /* CONFIG_NFS_V3 */
107 static struct dentry
*nfs_atomic_lookup(struct inode
*, struct dentry
*, struct nameidata
*);
108 static int nfs_open_create(struct inode
*dir
, struct dentry
*dentry
, int mode
, struct nameidata
*nd
);
109 const struct inode_operations nfs4_dir_inode_operations
= {
110 .create
= nfs_open_create
,
111 .lookup
= nfs_atomic_lookup
,
113 .unlink
= nfs_unlink
,
114 .symlink
= nfs_symlink
,
118 .rename
= nfs_rename
,
119 .permission
= nfs_permission
,
120 .getattr
= nfs_getattr
,
121 .setattr
= nfs_setattr
,
122 .getxattr
= nfs4_getxattr
,
123 .setxattr
= nfs4_setxattr
,
124 .listxattr
= nfs4_listxattr
,
127 #endif /* CONFIG_NFS_V4 */
133 nfs_opendir(struct inode
*inode
, struct file
*filp
)
137 dfprintk(FILE, "NFS: open dir(%s/%s)\n",
138 filp
->f_path
.dentry
->d_parent
->d_name
.name
,
139 filp
->f_path
.dentry
->d_name
.name
);
141 nfs_inc_stats(inode
, NFSIOS_VFSOPEN
);
143 /* Call generic open code in order to cache credentials */
144 res
= nfs_open(inode
, filp
);
145 if (filp
->f_path
.dentry
== filp
->f_path
.mnt
->mnt_root
) {
146 /* This is a mountpoint, so d_revalidate will never
147 * have been called, so we need to refresh the
148 * inode (for close-open consistency) ourselves.
150 __nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
155 typedef __be32
* (*decode_dirent_t
)(__be32
*, struct nfs_entry
*, int);
159 unsigned long page_index
;
162 loff_t current_index
;
163 struct nfs_entry
*entry
;
164 decode_dirent_t decode
;
166 unsigned long timestamp
;
167 unsigned long gencount
;
169 } nfs_readdir_descriptor_t
;
171 /* Now we cache directories properly, by stuffing the dirent
172 * data directly in the page cache.
174 * Inode invalidation due to refresh etc. takes care of
175 * _everything_, no sloppy entry flushing logic, no extraneous
176 * copying, network direct to page cache, the way it was meant
179 * NOTE: Dirent information verification is done always by the
180 * page-in of the RPC reply, nowhere else, this simplies
181 * things substantially.
184 int nfs_readdir_filler(nfs_readdir_descriptor_t
*desc
, struct page
*page
)
186 struct file
*file
= desc
->file
;
187 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
188 struct rpc_cred
*cred
= nfs_file_cred(file
);
189 unsigned long timestamp
, gencount
;
192 dfprintk(DIRCACHE
, "NFS: %s: reading cookie %Lu into page %lu\n",
193 __func__
, (long long)desc
->entry
->cookie
,
198 gencount
= nfs_inc_attr_generation_counter();
199 error
= NFS_PROTO(inode
)->readdir(file
->f_path
.dentry
, cred
, desc
->entry
->cookie
, page
,
200 NFS_SERVER(inode
)->dtsize
, desc
->plus
);
202 /* We requested READDIRPLUS, but the server doesn't grok it */
203 if (error
== -ENOTSUPP
&& desc
->plus
) {
204 NFS_SERVER(inode
)->caps
&= ~NFS_CAP_READDIRPLUS
;
205 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
211 desc
->timestamp
= timestamp
;
212 desc
->gencount
= gencount
;
213 desc
->timestamp_valid
= 1;
214 SetPageUptodate(page
);
215 /* Ensure consistent page alignment of the data.
216 * Note: assumes we have exclusive access to this mapping either
217 * through inode->i_mutex or some other mechanism.
219 if (invalidate_inode_pages2_range(inode
->i_mapping
, page
->index
+ 1, -1) < 0) {
220 /* Should never happen */
221 nfs_zap_mapping(inode
, inode
->i_mapping
);
231 int dir_decode(nfs_readdir_descriptor_t
*desc
)
233 __be32
*p
= desc
->ptr
;
234 p
= desc
->decode(p
, desc
->entry
, desc
->plus
);
238 if (desc
->timestamp_valid
) {
239 desc
->entry
->fattr
->time_start
= desc
->timestamp
;
240 desc
->entry
->fattr
->gencount
= desc
->gencount
;
242 desc
->entry
->fattr
->valid
&= ~NFS_ATTR_FATTR
;
247 void dir_page_release(nfs_readdir_descriptor_t
*desc
)
250 page_cache_release(desc
->page
);
256 * Given a pointer to a buffer that has already been filled by a call
257 * to readdir, find the next entry with cookie '*desc->dir_cookie'.
259 * If the end of the buffer has been reached, return -EAGAIN, if not,
260 * return the offset within the buffer of the next entry to be
264 int find_dirent(nfs_readdir_descriptor_t
*desc
)
266 struct nfs_entry
*entry
= desc
->entry
;
270 while((status
= dir_decode(desc
)) == 0) {
271 dfprintk(DIRCACHE
, "NFS: %s: examining cookie %Lu\n",
272 __func__
, (unsigned long long)entry
->cookie
);
273 if (entry
->prev_cookie
== *desc
->dir_cookie
)
275 if (loop_count
++ > 200) {
284 * Given a pointer to a buffer that has already been filled by a call
285 * to readdir, find the entry at offset 'desc->file->f_pos'.
287 * If the end of the buffer has been reached, return -EAGAIN, if not,
288 * return the offset within the buffer of the next entry to be
292 int find_dirent_index(nfs_readdir_descriptor_t
*desc
)
294 struct nfs_entry
*entry
= desc
->entry
;
299 status
= dir_decode(desc
);
303 dfprintk(DIRCACHE
, "NFS: found cookie %Lu at index %Ld\n",
304 (unsigned long long)entry
->cookie
, desc
->current_index
);
306 if (desc
->file
->f_pos
== desc
->current_index
) {
307 *desc
->dir_cookie
= entry
->cookie
;
310 desc
->current_index
++;
311 if (loop_count
++ > 200) {
320 * Find the given page, and call find_dirent() or find_dirent_index in
321 * order to try to return the next entry.
324 int find_dirent_page(nfs_readdir_descriptor_t
*desc
)
326 struct inode
*inode
= desc
->file
->f_path
.dentry
->d_inode
;
330 dfprintk(DIRCACHE
, "NFS: %s: searching page %ld for target %Lu\n",
331 __func__
, desc
->page_index
,
332 (long long) *desc
->dir_cookie
);
334 /* If we find the page in the page_cache, we cannot be sure
335 * how fresh the data is, so we will ignore readdir_plus attributes.
337 desc
->timestamp_valid
= 0;
338 page
= read_cache_page(inode
->i_mapping
, desc
->page_index
,
339 (filler_t
*)nfs_readdir_filler
, desc
);
341 status
= PTR_ERR(page
);
345 /* NOTE: Someone else may have changed the READDIRPLUS flag */
347 desc
->ptr
= kmap(page
); /* matching kunmap in nfs_do_filldir */
348 if (*desc
->dir_cookie
!= 0)
349 status
= find_dirent(desc
);
351 status
= find_dirent_index(desc
);
353 dir_page_release(desc
);
355 dfprintk(DIRCACHE
, "NFS: %s: returns %d\n", __func__
, status
);
360 * Recurse through the page cache pages, and return a
361 * filled nfs_entry structure of the next directory entry if possible.
363 * The target for the search is '*desc->dir_cookie' if non-0,
364 * 'desc->file->f_pos' otherwise
367 int readdir_search_pagecache(nfs_readdir_descriptor_t
*desc
)
372 /* Always search-by-index from the beginning of the cache */
373 if (*desc
->dir_cookie
== 0) {
374 dfprintk(DIRCACHE
, "NFS: readdir_search_pagecache() searching for offset %Ld\n",
375 (long long)desc
->file
->f_pos
);
376 desc
->page_index
= 0;
377 desc
->entry
->cookie
= desc
->entry
->prev_cookie
= 0;
378 desc
->entry
->eof
= 0;
379 desc
->current_index
= 0;
381 dfprintk(DIRCACHE
, "NFS: readdir_search_pagecache() searching for cookie %Lu\n",
382 (unsigned long long)*desc
->dir_cookie
);
385 res
= find_dirent_page(desc
);
388 /* Align to beginning of next page */
390 if (loop_count
++ > 200) {
396 dfprintk(DIRCACHE
, "NFS: %s: returns %d\n", __func__
, res
);
400 static inline unsigned int dt_type(struct inode
*inode
)
402 return (inode
->i_mode
>> 12) & 15;
405 static struct dentry
*nfs_readdir_lookup(nfs_readdir_descriptor_t
*desc
);
408 * Once we've found the start of the dirent within a page: fill 'er up...
411 int nfs_do_filldir(nfs_readdir_descriptor_t
*desc
, void *dirent
,
414 struct file
*file
= desc
->file
;
415 struct nfs_entry
*entry
= desc
->entry
;
416 struct dentry
*dentry
= NULL
;
421 dfprintk(DIRCACHE
, "NFS: nfs_do_filldir() filling starting @ cookie %Lu\n",
422 (unsigned long long)entry
->cookie
);
425 unsigned d_type
= DT_UNKNOWN
;
426 /* Note: entry->prev_cookie contains the cookie for
427 * retrieving the current dirent on the server */
430 /* Get a dentry if we have one */
433 dentry
= nfs_readdir_lookup(desc
);
435 /* Use readdirplus info */
436 if (dentry
!= NULL
&& dentry
->d_inode
!= NULL
) {
437 d_type
= dt_type(dentry
->d_inode
);
438 fileid
= NFS_FILEID(dentry
->d_inode
);
441 res
= filldir(dirent
, entry
->name
, entry
->len
,
442 file
->f_pos
, nfs_compat_user_ino64(fileid
),
447 *desc
->dir_cookie
= entry
->cookie
;
448 if (dir_decode(desc
) != 0) {
452 if (loop_count
++ > 200) {
457 dir_page_release(desc
);
460 dfprintk(DIRCACHE
, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n",
461 (unsigned long long)*desc
->dir_cookie
, res
);
466 * If we cannot find a cookie in our cache, we suspect that this is
467 * because it points to a deleted file, so we ask the server to return
468 * whatever it thinks is the next entry. We then feed this to filldir.
469 * If all goes well, we should then be able to find our way round the
470 * cache on the next call to readdir_search_pagecache();
472 * NOTE: we cannot add the anonymous page to the pagecache because
473 * the data it contains might not be page aligned. Besides,
474 * we should already have a complete representation of the
475 * directory in the page cache by the time we get here.
478 int uncached_readdir(nfs_readdir_descriptor_t
*desc
, void *dirent
,
481 struct file
*file
= desc
->file
;
482 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
483 struct rpc_cred
*cred
= nfs_file_cred(file
);
484 struct page
*page
= NULL
;
486 unsigned long timestamp
, gencount
;
488 dfprintk(DIRCACHE
, "NFS: uncached_readdir() searching for cookie %Lu\n",
489 (unsigned long long)*desc
->dir_cookie
);
491 page
= alloc_page(GFP_HIGHUSER
);
497 gencount
= nfs_inc_attr_generation_counter();
498 status
= NFS_PROTO(inode
)->readdir(file
->f_path
.dentry
, cred
,
499 *desc
->dir_cookie
, page
,
500 NFS_SERVER(inode
)->dtsize
,
503 desc
->ptr
= kmap(page
); /* matching kunmap in nfs_do_filldir */
505 desc
->timestamp
= timestamp
;
506 desc
->gencount
= gencount
;
507 desc
->timestamp_valid
= 1;
508 if ((status
= dir_decode(desc
)) == 0)
509 desc
->entry
->prev_cookie
= *desc
->dir_cookie
;
515 status
= nfs_do_filldir(desc
, dirent
, filldir
);
517 /* Reset read descriptor so it searches the page cache from
518 * the start upon the next call to readdir_search_pagecache() */
519 desc
->page_index
= 0;
520 desc
->entry
->cookie
= desc
->entry
->prev_cookie
= 0;
521 desc
->entry
->eof
= 0;
523 dfprintk(DIRCACHE
, "NFS: %s: returns %d\n",
527 dir_page_release(desc
);
531 /* The file offset position represents the dirent entry number. A
532 last cookie cache takes care of the common case of reading the
535 static int nfs_readdir(struct file
*filp
, void *dirent
, filldir_t filldir
)
537 struct dentry
*dentry
= filp
->f_path
.dentry
;
538 struct inode
*inode
= dentry
->d_inode
;
539 nfs_readdir_descriptor_t my_desc
,
541 struct nfs_entry my_entry
;
544 dfprintk(FILE, "NFS: readdir(%s/%s) starting at cookie %llu\n",
545 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
546 (long long)filp
->f_pos
);
547 nfs_inc_stats(inode
, NFSIOS_VFSGETDENTS
);
550 * filp->f_pos points to the dirent entry number.
551 * *desc->dir_cookie has the cookie for the next entry. We have
552 * to either find the entry with the appropriate number or
553 * revalidate the cookie.
555 memset(desc
, 0, sizeof(*desc
));
558 desc
->dir_cookie
= &nfs_file_open_context(filp
)->dir_cookie
;
559 desc
->decode
= NFS_PROTO(inode
)->decode_dirent
;
560 desc
->plus
= NFS_USE_READDIRPLUS(inode
);
562 my_entry
.cookie
= my_entry
.prev_cookie
= 0;
564 my_entry
.fh
= nfs_alloc_fhandle();
565 my_entry
.fattr
= nfs_alloc_fattr();
566 if (my_entry
.fh
== NULL
|| my_entry
.fattr
== NULL
)
567 goto out_alloc_failed
;
569 desc
->entry
= &my_entry
;
571 nfs_block_sillyrename(dentry
);
572 res
= nfs_revalidate_mapping(inode
, filp
->f_mapping
);
576 while(!desc
->entry
->eof
) {
577 res
= readdir_search_pagecache(desc
);
579 if (res
== -EBADCOOKIE
) {
580 /* This means either end of directory */
581 if (*desc
->dir_cookie
&& desc
->entry
->cookie
!= *desc
->dir_cookie
) {
582 /* Or that the server has 'lost' a cookie */
583 res
= uncached_readdir(desc
, dirent
, filldir
);
590 if (res
== -ETOOSMALL
&& desc
->plus
) {
591 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_I(inode
)->flags
);
592 nfs_zap_caches(inode
);
594 desc
->entry
->eof
= 0;
600 res
= nfs_do_filldir(desc
, dirent
, filldir
);
607 nfs_unblock_sillyrename(dentry
);
611 nfs_free_fattr(my_entry
.fattr
);
612 nfs_free_fhandle(my_entry
.fh
);
613 dfprintk(FILE, "NFS: readdir(%s/%s) returns %d\n",
614 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
619 static loff_t
nfs_llseek_dir(struct file
*filp
, loff_t offset
, int origin
)
621 struct dentry
*dentry
= filp
->f_path
.dentry
;
622 struct inode
*inode
= dentry
->d_inode
;
624 dfprintk(FILE, "NFS: llseek dir(%s/%s, %lld, %d)\n",
625 dentry
->d_parent
->d_name
.name
,
629 mutex_lock(&inode
->i_mutex
);
632 offset
+= filp
->f_pos
;
640 if (offset
!= filp
->f_pos
) {
641 filp
->f_pos
= offset
;
642 nfs_file_open_context(filp
)->dir_cookie
= 0;
645 mutex_unlock(&inode
->i_mutex
);
650 * All directory operations under NFS are synchronous, so fsync()
651 * is a dummy operation.
653 static int nfs_fsync_dir(struct file
*filp
, int datasync
)
655 struct dentry
*dentry
= filp
->f_path
.dentry
;
657 dfprintk(FILE, "NFS: fsync dir(%s/%s) datasync %d\n",
658 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
661 nfs_inc_stats(dentry
->d_inode
, NFSIOS_VFSFSYNC
);
666 * nfs_force_lookup_revalidate - Mark the directory as having changed
667 * @dir - pointer to directory inode
669 * This forces the revalidation code in nfs_lookup_revalidate() to do a
670 * full lookup on all child dentries of 'dir' whenever a change occurs
671 * on the server that might have invalidated our dcache.
673 * The caller should be holding dir->i_lock
675 void nfs_force_lookup_revalidate(struct inode
*dir
)
677 NFS_I(dir
)->cache_change_attribute
++;
681 * A check for whether or not the parent directory has changed.
682 * In the case it has, we assume that the dentries are untrustworthy
683 * and may need to be looked up again.
685 static int nfs_check_verifier(struct inode
*dir
, struct dentry
*dentry
)
689 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONE
)
691 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
693 /* Revalidate nfsi->cache_change_attribute before we declare a match */
694 if (nfs_revalidate_inode(NFS_SERVER(dir
), dir
) < 0)
696 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
702 * Return the intent data that applies to this particular path component
704 * Note that the current set of intents only apply to the very last
705 * component of the path.
706 * We check for this using LOOKUP_CONTINUE and LOOKUP_PARENT.
708 static inline unsigned int nfs_lookup_check_intent(struct nameidata
*nd
, unsigned int mask
)
710 if (nd
->flags
& (LOOKUP_CONTINUE
|LOOKUP_PARENT
))
712 return nd
->flags
& mask
;
716 * Use intent information to check whether or not we're going to do
717 * an O_EXCL create using this path component.
719 static int nfs_is_exclusive_create(struct inode
*dir
, struct nameidata
*nd
)
721 if (NFS_PROTO(dir
)->version
== 2)
723 return nd
&& nfs_lookup_check_intent(nd
, LOOKUP_EXCL
);
727 * Inode and filehandle revalidation for lookups.
729 * We force revalidation in the cases where the VFS sets LOOKUP_REVAL,
730 * or if the intent information indicates that we're about to open this
731 * particular file and the "nocto" mount flag is not set.
735 int nfs_lookup_verify_inode(struct inode
*inode
, struct nameidata
*nd
)
737 struct nfs_server
*server
= NFS_SERVER(inode
);
739 if (test_bit(NFS_INO_MOUNTPOINT
, &NFS_I(inode
)->flags
))
742 /* VFS wants an on-the-wire revalidation */
743 if (nd
->flags
& LOOKUP_REVAL
)
745 /* This is an open(2) */
746 if (nfs_lookup_check_intent(nd
, LOOKUP_OPEN
) != 0 &&
747 !(server
->flags
& NFS_MOUNT_NOCTO
) &&
748 (S_ISREG(inode
->i_mode
) ||
749 S_ISDIR(inode
->i_mode
)))
753 return nfs_revalidate_inode(server
, inode
);
755 return __nfs_revalidate_inode(server
, inode
);
759 * We judge how long we want to trust negative
760 * dentries by looking at the parent inode mtime.
762 * If parent mtime has changed, we revalidate, else we wait for a
763 * period corresponding to the parent's attribute cache timeout value.
766 int nfs_neg_need_reval(struct inode
*dir
, struct dentry
*dentry
,
767 struct nameidata
*nd
)
769 /* Don't revalidate a negative dentry if we're creating a new file */
770 if (nd
!= NULL
&& nfs_lookup_check_intent(nd
, LOOKUP_CREATE
) != 0)
772 if (NFS_SERVER(dir
)->flags
& NFS_MOUNT_LOOKUP_CACHE_NONEG
)
774 return !nfs_check_verifier(dir
, dentry
);
778 * This is called every time the dcache has a lookup hit,
779 * and we should check whether we can really trust that
782 * NOTE! The hit can be a negative hit too, don't assume
785 * If the parent directory is seen to have changed, we throw out the
786 * cached dentry and do a new lookup.
788 static int nfs_lookup_revalidate(struct dentry
* dentry
, struct nameidata
*nd
)
792 struct dentry
*parent
;
793 struct nfs_fh
*fhandle
= NULL
;
794 struct nfs_fattr
*fattr
= NULL
;
797 parent
= dget_parent(dentry
);
798 dir
= parent
->d_inode
;
799 nfs_inc_stats(dir
, NFSIOS_DENTRYREVALIDATE
);
800 inode
= dentry
->d_inode
;
803 if (nfs_neg_need_reval(dir
, dentry
, nd
))
808 if (is_bad_inode(inode
)) {
809 dfprintk(LOOKUPCACHE
, "%s: %s/%s has dud inode\n",
810 __func__
, dentry
->d_parent
->d_name
.name
,
811 dentry
->d_name
.name
);
815 if (nfs_have_delegation(inode
, FMODE_READ
))
816 goto out_set_verifier
;
818 /* Force a full look up iff the parent directory has changed */
819 if (!nfs_is_exclusive_create(dir
, nd
) && nfs_check_verifier(dir
, dentry
)) {
820 if (nfs_lookup_verify_inode(inode
, nd
))
825 if (NFS_STALE(inode
))
829 fhandle
= nfs_alloc_fhandle();
830 fattr
= nfs_alloc_fattr();
831 if (fhandle
== NULL
|| fattr
== NULL
)
834 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
);
837 if (nfs_compare_fh(NFS_FH(inode
), fhandle
))
839 if ((error
= nfs_refresh_inode(inode
, fattr
)) != 0)
842 nfs_free_fattr(fattr
);
843 nfs_free_fhandle(fhandle
);
845 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
848 dfprintk(LOOKUPCACHE
, "NFS: %s(%s/%s) is valid\n",
849 __func__
, dentry
->d_parent
->d_name
.name
,
850 dentry
->d_name
.name
);
855 nfs_mark_for_revalidate(dir
);
856 if (inode
&& S_ISDIR(inode
->i_mode
)) {
857 /* Purge readdir caches. */
858 nfs_zap_caches(inode
);
859 /* If we have submounts, don't unhash ! */
860 if (have_submounts(dentry
))
862 if (dentry
->d_flags
& DCACHE_DISCONNECTED
)
864 shrink_dcache_parent(dentry
);
867 nfs_free_fattr(fattr
);
868 nfs_free_fhandle(fhandle
);
870 dfprintk(LOOKUPCACHE
, "NFS: %s(%s/%s) is invalid\n",
871 __func__
, dentry
->d_parent
->d_name
.name
,
872 dentry
->d_name
.name
);
875 nfs_free_fattr(fattr
);
876 nfs_free_fhandle(fhandle
);
878 dfprintk(LOOKUPCACHE
, "NFS: %s(%s/%s) lookup returned error %d\n",
879 __func__
, dentry
->d_parent
->d_name
.name
,
880 dentry
->d_name
.name
, error
);
885 * This is called from dput() when d_count is going to 0.
887 static int nfs_dentry_delete(struct dentry
*dentry
)
889 dfprintk(VFS
, "NFS: dentry_delete(%s/%s, %x)\n",
890 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
893 /* Unhash any dentry with a stale inode */
894 if (dentry
->d_inode
!= NULL
&& NFS_STALE(dentry
->d_inode
))
897 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
898 /* Unhash it, so that ->d_iput() would be called */
901 if (!(dentry
->d_sb
->s_flags
& MS_ACTIVE
)) {
902 /* Unhash it, so that ancestors of killed async unlink
903 * files will be cleaned up during umount */
910 static void nfs_drop_nlink(struct inode
*inode
)
912 spin_lock(&inode
->i_lock
);
913 if (inode
->i_nlink
> 0)
915 spin_unlock(&inode
->i_lock
);
919 * Called when the dentry loses inode.
920 * We use it to clean up silly-renamed files.
922 static void nfs_dentry_iput(struct dentry
*dentry
, struct inode
*inode
)
924 if (S_ISDIR(inode
->i_mode
))
925 /* drop any readdir cache as it could easily be old */
926 NFS_I(inode
)->cache_validity
|= NFS_INO_INVALID_DATA
;
928 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
930 nfs_complete_unlink(dentry
, inode
);
935 const struct dentry_operations nfs_dentry_operations
= {
936 .d_revalidate
= nfs_lookup_revalidate
,
937 .d_delete
= nfs_dentry_delete
,
938 .d_iput
= nfs_dentry_iput
,
941 static struct dentry
*nfs_lookup(struct inode
*dir
, struct dentry
* dentry
, struct nameidata
*nd
)
944 struct dentry
*parent
;
945 struct inode
*inode
= NULL
;
946 struct nfs_fh
*fhandle
= NULL
;
947 struct nfs_fattr
*fattr
= NULL
;
950 dfprintk(VFS
, "NFS: lookup(%s/%s)\n",
951 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
952 nfs_inc_stats(dir
, NFSIOS_VFSLOOKUP
);
954 res
= ERR_PTR(-ENAMETOOLONG
);
955 if (dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
)
958 dentry
->d_op
= NFS_PROTO(dir
)->dentry_ops
;
961 * If we're doing an exclusive create, optimize away the lookup
962 * but don't hash the dentry.
964 if (nfs_is_exclusive_create(dir
, nd
)) {
965 d_instantiate(dentry
, NULL
);
970 res
= ERR_PTR(-ENOMEM
);
971 fhandle
= nfs_alloc_fhandle();
972 fattr
= nfs_alloc_fattr();
973 if (fhandle
== NULL
|| fattr
== NULL
)
976 parent
= dentry
->d_parent
;
977 /* Protect against concurrent sillydeletes */
978 nfs_block_sillyrename(parent
);
979 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
);
980 if (error
== -ENOENT
)
983 res
= ERR_PTR(error
);
984 goto out_unblock_sillyrename
;
986 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
);
987 res
= (struct dentry
*)inode
;
989 goto out_unblock_sillyrename
;
992 res
= d_materialise_unique(dentry
, inode
);
995 goto out_unblock_sillyrename
;
998 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
999 out_unblock_sillyrename
:
1000 nfs_unblock_sillyrename(parent
);
1002 nfs_free_fattr(fattr
);
1003 nfs_free_fhandle(fhandle
);
1007 #ifdef CONFIG_NFS_V4
1008 static int nfs_open_revalidate(struct dentry
*, struct nameidata
*);
1010 const struct dentry_operations nfs4_dentry_operations
= {
1011 .d_revalidate
= nfs_open_revalidate
,
1012 .d_delete
= nfs_dentry_delete
,
1013 .d_iput
= nfs_dentry_iput
,
1017 * Use intent information to determine whether we need to substitute
1018 * the NFSv4-style stateful OPEN for the LOOKUP call
1020 static int is_atomic_open(struct nameidata
*nd
)
1022 if (nd
== NULL
|| nfs_lookup_check_intent(nd
, LOOKUP_OPEN
) == 0)
1024 /* NFS does not (yet) have a stateful open for directories */
1025 if (nd
->flags
& LOOKUP_DIRECTORY
)
1027 /* Are we trying to write to a read only partition? */
1028 if (__mnt_is_readonly(nd
->path
.mnt
) &&
1029 (nd
->intent
.open
.flags
& (O_CREAT
|O_TRUNC
|FMODE_WRITE
)))
1034 static struct nfs_open_context
*nameidata_to_nfs_open_context(struct dentry
*dentry
, struct nameidata
*nd
)
1036 struct path path
= {
1037 .mnt
= nd
->path
.mnt
,
1040 struct nfs_open_context
*ctx
;
1041 struct rpc_cred
*cred
;
1042 fmode_t fmode
= nd
->intent
.open
.flags
& (FMODE_READ
| FMODE_WRITE
| FMODE_EXEC
);
1044 cred
= rpc_lookup_cred();
1046 return ERR_CAST(cred
);
1047 ctx
= alloc_nfs_open_context(&path
, cred
, fmode
);
1050 return ERR_PTR(-ENOMEM
);
1054 static int do_open(struct inode
*inode
, struct file
*filp
)
1056 nfs_fscache_set_inode_cookie(inode
, filp
);
1060 static int nfs_intent_set_file(struct nameidata
*nd
, struct nfs_open_context
*ctx
)
1065 /* If the open_intent is for execute, we have an extra check to make */
1066 if (ctx
->mode
& FMODE_EXEC
) {
1067 ret
= nfs_may_open(ctx
->path
.dentry
->d_inode
,
1069 nd
->intent
.open
.flags
);
1073 filp
= lookup_instantiate_filp(nd
, ctx
->path
.dentry
, do_open
);
1075 ret
= PTR_ERR(filp
);
1077 nfs_file_set_open_context(filp
, ctx
);
1079 put_nfs_open_context(ctx
);
1083 static struct dentry
*nfs_atomic_lookup(struct inode
*dir
, struct dentry
*dentry
, struct nameidata
*nd
)
1085 struct nfs_open_context
*ctx
;
1087 struct dentry
*res
= NULL
;
1088 struct inode
*inode
;
1091 dfprintk(VFS
, "NFS: atomic_lookup(%s/%ld), %s\n",
1092 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1094 /* Check that we are indeed trying to open this file */
1095 if (!is_atomic_open(nd
))
1098 if (dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
) {
1099 res
= ERR_PTR(-ENAMETOOLONG
);
1102 dentry
->d_op
= NFS_PROTO(dir
)->dentry_ops
;
1104 /* Let vfs_create() deal with O_EXCL. Instantiate, but don't hash
1106 if (nd
->flags
& LOOKUP_EXCL
) {
1107 d_instantiate(dentry
, NULL
);
1111 ctx
= nameidata_to_nfs_open_context(dentry
, nd
);
1112 res
= ERR_CAST(ctx
);
1116 open_flags
= nd
->intent
.open
.flags
;
1117 if (nd
->flags
& LOOKUP_CREATE
) {
1118 attr
.ia_mode
= nd
->intent
.open
.create_mode
;
1119 attr
.ia_valid
= ATTR_MODE
;
1120 if (!IS_POSIXACL(dir
))
1121 attr
.ia_mode
&= ~current_umask();
1123 open_flags
&= ~O_EXCL
;
1125 BUG_ON(open_flags
& O_CREAT
);
1128 /* Open the file on the server */
1129 nfs_block_sillyrename(dentry
->d_parent
);
1130 inode
= nfs4_atomic_open(dir
, ctx
, open_flags
, &attr
);
1131 if (IS_ERR(inode
)) {
1132 nfs_unblock_sillyrename(dentry
->d_parent
);
1133 put_nfs_open_context(ctx
);
1134 switch (PTR_ERR(inode
)) {
1135 /* Make a negative dentry */
1137 d_add(dentry
, NULL
);
1140 /* This turned out not to be a regular file */
1145 if (!(nd
->intent
.open
.flags
& O_NOFOLLOW
))
1149 res
= ERR_CAST(inode
);
1153 res
= d_add_unique(dentry
, inode
);
1155 dput(ctx
->path
.dentry
);
1156 ctx
->path
.dentry
= dget(res
);
1159 nfs_intent_set_file(nd
, ctx
);
1160 nfs_unblock_sillyrename(dentry
->d_parent
);
1162 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1165 return nfs_lookup(dir
, dentry
, nd
);
1168 static int nfs_open_revalidate(struct dentry
*dentry
, struct nameidata
*nd
)
1170 struct dentry
*parent
= NULL
;
1171 struct inode
*inode
= dentry
->d_inode
;
1173 struct nfs_open_context
*ctx
;
1174 int openflags
, ret
= 0;
1176 if (!is_atomic_open(nd
) || d_mountpoint(dentry
))
1178 parent
= dget_parent(dentry
);
1179 dir
= parent
->d_inode
;
1180 /* We can't create new files in nfs_open_revalidate(), so we
1181 * optimize away revalidation of negative dentries.
1183 if (inode
== NULL
) {
1184 if (!nfs_neg_need_reval(dir
, dentry
, nd
))
1189 /* NFS only supports OPEN on regular files */
1190 if (!S_ISREG(inode
->i_mode
))
1192 openflags
= nd
->intent
.open
.flags
;
1193 /* We cannot do exclusive creation on a positive dentry */
1194 if ((openflags
& (O_CREAT
|O_EXCL
)) == (O_CREAT
|O_EXCL
))
1196 /* We can't create new files, or truncate existing ones here */
1197 openflags
&= ~(O_CREAT
|O_EXCL
|O_TRUNC
);
1199 ctx
= nameidata_to_nfs_open_context(dentry
, nd
);
1204 * Note: we're not holding inode->i_mutex and so may be racing with
1205 * operations that change the directory. We therefore save the
1206 * change attribute *before* we do the RPC call.
1208 inode
= nfs4_atomic_open(dir
, ctx
, openflags
, NULL
);
1209 if (IS_ERR(inode
)) {
1210 ret
= PTR_ERR(inode
);
1223 if (inode
== dentry
->d_inode
) {
1224 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1225 nfs_intent_set_file(nd
, ctx
);
1235 put_nfs_open_context(ctx
);
1241 return nfs_lookup_revalidate(dentry
, nd
);
1244 static int nfs_open_create(struct inode
*dir
, struct dentry
*dentry
, int mode
,
1245 struct nameidata
*nd
)
1247 struct nfs_open_context
*ctx
= NULL
;
1252 dfprintk(VFS
, "NFS: create(%s/%ld), %s\n",
1253 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1255 attr
.ia_mode
= mode
;
1256 attr
.ia_valid
= ATTR_MODE
;
1258 if ((nd
->flags
& LOOKUP_CREATE
) != 0) {
1259 open_flags
= nd
->intent
.open
.flags
;
1261 ctx
= nameidata_to_nfs_open_context(dentry
, nd
);
1262 error
= PTR_ERR(ctx
);
1267 error
= NFS_PROTO(dir
)->create(dir
, dentry
, &attr
, open_flags
, ctx
);
1271 nfs_intent_set_file(nd
, ctx
);
1275 put_nfs_open_context(ctx
);
1281 #endif /* CONFIG_NFSV4 */
1283 static struct dentry
*nfs_readdir_lookup(nfs_readdir_descriptor_t
*desc
)
1285 struct dentry
*parent
= desc
->file
->f_path
.dentry
;
1286 struct inode
*dir
= parent
->d_inode
;
1287 struct nfs_entry
*entry
= desc
->entry
;
1288 struct dentry
*dentry
, *alias
;
1289 struct qstr name
= {
1290 .name
= entry
->name
,
1293 struct inode
*inode
;
1294 unsigned long verf
= nfs_save_change_attribute(dir
);
1298 if (name
.name
[0] == '.' && name
.name
[1] == '.')
1299 return dget_parent(parent
);
1302 if (name
.name
[0] == '.')
1303 return dget(parent
);
1306 spin_lock(&dir
->i_lock
);
1307 if (NFS_I(dir
)->cache_validity
& NFS_INO_INVALID_DATA
) {
1308 spin_unlock(&dir
->i_lock
);
1311 spin_unlock(&dir
->i_lock
);
1313 name
.hash
= full_name_hash(name
.name
, name
.len
);
1314 dentry
= d_lookup(parent
, &name
);
1315 if (dentry
!= NULL
) {
1316 /* Is this a positive dentry that matches the readdir info? */
1317 if (dentry
->d_inode
!= NULL
&&
1318 (NFS_FILEID(dentry
->d_inode
) == entry
->ino
||
1319 d_mountpoint(dentry
))) {
1320 if (!desc
->plus
|| entry
->fh
->size
== 0)
1322 if (nfs_compare_fh(NFS_FH(dentry
->d_inode
),
1326 /* No, so d_drop to allow one to be created */
1330 if (!desc
->plus
|| !(entry
->fattr
->valid
& NFS_ATTR_FATTR
))
1332 if (name
.len
> NFS_SERVER(dir
)->namelen
)
1334 /* Note: caller is already holding the dir->i_mutex! */
1335 dentry
= d_alloc(parent
, &name
);
1338 dentry
->d_op
= NFS_PROTO(dir
)->dentry_ops
;
1339 inode
= nfs_fhget(dentry
->d_sb
, entry
->fh
, entry
->fattr
);
1340 if (IS_ERR(inode
)) {
1345 alias
= d_materialise_unique(dentry
, inode
);
1346 if (alias
!= NULL
) {
1354 nfs_set_verifier(dentry
, verf
);
1359 * Code common to create, mkdir, and mknod.
1361 int nfs_instantiate(struct dentry
*dentry
, struct nfs_fh
*fhandle
,
1362 struct nfs_fattr
*fattr
)
1364 struct dentry
*parent
= dget_parent(dentry
);
1365 struct inode
*dir
= parent
->d_inode
;
1366 struct inode
*inode
;
1367 int error
= -EACCES
;
1371 /* We may have been initialized further down */
1372 if (dentry
->d_inode
)
1374 if (fhandle
->size
== 0) {
1375 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
);
1379 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1380 if (!(fattr
->valid
& NFS_ATTR_FATTR
)) {
1381 struct nfs_server
*server
= NFS_SB(dentry
->d_sb
);
1382 error
= server
->nfs_client
->rpc_ops
->getattr(server
, fhandle
, fattr
);
1386 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
);
1387 error
= PTR_ERR(inode
);
1390 d_add(dentry
, inode
);
1395 nfs_mark_for_revalidate(dir
);
1401 * Following a failed create operation, we drop the dentry rather
1402 * than retain a negative dentry. This avoids a problem in the event
1403 * that the operation succeeded on the server, but an error in the
1404 * reply path made it appear to have failed.
1406 static int nfs_create(struct inode
*dir
, struct dentry
*dentry
, int mode
,
1407 struct nameidata
*nd
)
1412 dfprintk(VFS
, "NFS: create(%s/%ld), %s\n",
1413 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1415 attr
.ia_mode
= mode
;
1416 attr
.ia_valid
= ATTR_MODE
;
1418 error
= NFS_PROTO(dir
)->create(dir
, dentry
, &attr
, 0, NULL
);
1428 * See comments for nfs_proc_create regarding failed operations.
1431 nfs_mknod(struct inode
*dir
, struct dentry
*dentry
, int mode
, dev_t rdev
)
1436 dfprintk(VFS
, "NFS: mknod(%s/%ld), %s\n",
1437 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1439 if (!new_valid_dev(rdev
))
1442 attr
.ia_mode
= mode
;
1443 attr
.ia_valid
= ATTR_MODE
;
1445 status
= NFS_PROTO(dir
)->mknod(dir
, dentry
, &attr
, rdev
);
1455 * See comments for nfs_proc_create regarding failed operations.
1457 static int nfs_mkdir(struct inode
*dir
, struct dentry
*dentry
, int mode
)
1462 dfprintk(VFS
, "NFS: mkdir(%s/%ld), %s\n",
1463 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1465 attr
.ia_valid
= ATTR_MODE
;
1466 attr
.ia_mode
= mode
| S_IFDIR
;
1468 error
= NFS_PROTO(dir
)->mkdir(dir
, dentry
, &attr
);
1477 static void nfs_dentry_handle_enoent(struct dentry
*dentry
)
1479 if (dentry
->d_inode
!= NULL
&& !d_unhashed(dentry
))
1483 static int nfs_rmdir(struct inode
*dir
, struct dentry
*dentry
)
1487 dfprintk(VFS
, "NFS: rmdir(%s/%ld), %s\n",
1488 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1490 error
= NFS_PROTO(dir
)->rmdir(dir
, &dentry
->d_name
);
1491 /* Ensure the VFS deletes this inode */
1492 if (error
== 0 && dentry
->d_inode
!= NULL
)
1493 clear_nlink(dentry
->d_inode
);
1494 else if (error
== -ENOENT
)
1495 nfs_dentry_handle_enoent(dentry
);
1500 static int nfs_sillyrename(struct inode
*dir
, struct dentry
*dentry
)
1502 static unsigned int sillycounter
;
1503 const int fileidsize
= sizeof(NFS_FILEID(dentry
->d_inode
))*2;
1504 const int countersize
= sizeof(sillycounter
)*2;
1505 const int slen
= sizeof(".nfs")+fileidsize
+countersize
-1;
1508 struct dentry
*sdentry
;
1511 dfprintk(VFS
, "NFS: silly-rename(%s/%s, ct=%d)\n",
1512 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
1513 atomic_read(&dentry
->d_count
));
1514 nfs_inc_stats(dir
, NFSIOS_SILLYRENAME
);
1517 * We don't allow a dentry to be silly-renamed twice.
1520 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
)
1523 sprintf(silly
, ".nfs%*.*Lx",
1524 fileidsize
, fileidsize
,
1525 (unsigned long long)NFS_FILEID(dentry
->d_inode
));
1527 /* Return delegation in anticipation of the rename */
1528 nfs_inode_return_delegation(dentry
->d_inode
);
1532 char *suffix
= silly
+ slen
- countersize
;
1536 sprintf(suffix
, "%*.*x", countersize
, countersize
, sillycounter
);
1538 dfprintk(VFS
, "NFS: trying to rename %s to %s\n",
1539 dentry
->d_name
.name
, silly
);
1541 sdentry
= lookup_one_len(silly
, dentry
->d_parent
, slen
);
1543 * N.B. Better to return EBUSY here ... it could be
1544 * dangerous to delete the file while it's in use.
1546 if (IS_ERR(sdentry
))
1548 } while(sdentry
->d_inode
!= NULL
); /* need negative lookup */
1550 qsilly
.name
= silly
;
1551 qsilly
.len
= strlen(silly
);
1552 if (dentry
->d_inode
) {
1553 error
= NFS_PROTO(dir
)->rename(dir
, &dentry
->d_name
,
1555 nfs_mark_for_revalidate(dentry
->d_inode
);
1557 error
= NFS_PROTO(dir
)->rename(dir
, &dentry
->d_name
,
1560 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1561 d_move(dentry
, sdentry
);
1562 error
= nfs_async_unlink(dir
, dentry
);
1563 /* If we return 0 we don't unlink */
1571 * Remove a file after making sure there are no pending writes,
1572 * and after checking that the file has only one user.
1574 * We invalidate the attribute cache and free the inode prior to the operation
1575 * to avoid possible races if the server reuses the inode.
1577 static int nfs_safe_remove(struct dentry
*dentry
)
1579 struct inode
*dir
= dentry
->d_parent
->d_inode
;
1580 struct inode
*inode
= dentry
->d_inode
;
1583 dfprintk(VFS
, "NFS: safe_remove(%s/%s)\n",
1584 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
1586 /* If the dentry was sillyrenamed, we simply call d_delete() */
1587 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1592 if (inode
!= NULL
) {
1593 nfs_inode_return_delegation(inode
);
1594 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1595 /* The VFS may want to delete this inode */
1597 nfs_drop_nlink(inode
);
1598 nfs_mark_for_revalidate(inode
);
1600 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1601 if (error
== -ENOENT
)
1602 nfs_dentry_handle_enoent(dentry
);
1607 /* We do silly rename. In case sillyrename() returns -EBUSY, the inode
1608 * belongs to an active ".nfs..." file and we return -EBUSY.
1610 * If sillyrename() returns 0, we do nothing, otherwise we unlink.
1612 static int nfs_unlink(struct inode
*dir
, struct dentry
*dentry
)
1615 int need_rehash
= 0;
1617 dfprintk(VFS
, "NFS: unlink(%s/%ld, %s)\n", dir
->i_sb
->s_id
,
1618 dir
->i_ino
, dentry
->d_name
.name
);
1620 spin_lock(&dcache_lock
);
1621 spin_lock(&dentry
->d_lock
);
1622 if (atomic_read(&dentry
->d_count
) > 1) {
1623 spin_unlock(&dentry
->d_lock
);
1624 spin_unlock(&dcache_lock
);
1625 /* Start asynchronous writeout of the inode */
1626 write_inode_now(dentry
->d_inode
, 0);
1627 error
= nfs_sillyrename(dir
, dentry
);
1630 if (!d_unhashed(dentry
)) {
1634 spin_unlock(&dentry
->d_lock
);
1635 spin_unlock(&dcache_lock
);
1636 error
= nfs_safe_remove(dentry
);
1637 if (!error
|| error
== -ENOENT
) {
1638 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1639 } else if (need_rehash
)
1645 * To create a symbolic link, most file systems instantiate a new inode,
1646 * add a page to it containing the path, then write it out to the disk
1647 * using prepare_write/commit_write.
1649 * Unfortunately the NFS client can't create the in-core inode first
1650 * because it needs a file handle to create an in-core inode (see
1651 * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the
1652 * symlink request has completed on the server.
1654 * So instead we allocate a raw page, copy the symname into it, then do
1655 * the SYMLINK request with the page as the buffer. If it succeeds, we
1656 * now have a new file handle and can instantiate an in-core NFS inode
1657 * and move the raw page into its mapping.
1659 static int nfs_symlink(struct inode
*dir
, struct dentry
*dentry
, const char *symname
)
1661 struct pagevec lru_pvec
;
1665 unsigned int pathlen
= strlen(symname
);
1668 dfprintk(VFS
, "NFS: symlink(%s/%ld, %s, %s)\n", dir
->i_sb
->s_id
,
1669 dir
->i_ino
, dentry
->d_name
.name
, symname
);
1671 if (pathlen
> PAGE_SIZE
)
1672 return -ENAMETOOLONG
;
1674 attr
.ia_mode
= S_IFLNK
| S_IRWXUGO
;
1675 attr
.ia_valid
= ATTR_MODE
;
1677 page
= alloc_page(GFP_HIGHUSER
);
1681 kaddr
= kmap_atomic(page
, KM_USER0
);
1682 memcpy(kaddr
, symname
, pathlen
);
1683 if (pathlen
< PAGE_SIZE
)
1684 memset(kaddr
+ pathlen
, 0, PAGE_SIZE
- pathlen
);
1685 kunmap_atomic(kaddr
, KM_USER0
);
1687 error
= NFS_PROTO(dir
)->symlink(dir
, dentry
, page
, pathlen
, &attr
);
1689 dfprintk(VFS
, "NFS: symlink(%s/%ld, %s, %s) error %d\n",
1690 dir
->i_sb
->s_id
, dir
->i_ino
,
1691 dentry
->d_name
.name
, symname
, error
);
1698 * No big deal if we can't add this page to the page cache here.
1699 * READLINK will get the missing page from the server if needed.
1701 pagevec_init(&lru_pvec
, 0);
1702 if (!add_to_page_cache(page
, dentry
->d_inode
->i_mapping
, 0,
1704 pagevec_add(&lru_pvec
, page
);
1705 pagevec_lru_add_file(&lru_pvec
);
1706 SetPageUptodate(page
);
1715 nfs_link(struct dentry
*old_dentry
, struct inode
*dir
, struct dentry
*dentry
)
1717 struct inode
*inode
= old_dentry
->d_inode
;
1720 dfprintk(VFS
, "NFS: link(%s/%s -> %s/%s)\n",
1721 old_dentry
->d_parent
->d_name
.name
, old_dentry
->d_name
.name
,
1722 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
1724 nfs_inode_return_delegation(inode
);
1727 error
= NFS_PROTO(dir
)->link(inode
, dir
, &dentry
->d_name
);
1729 atomic_inc(&inode
->i_count
);
1730 d_add(dentry
, inode
);
1737 * FIXME: Some nfsds, like the Linux user space nfsd, may generate a
1738 * different file handle for the same inode after a rename (e.g. when
1739 * moving to a different directory). A fail-safe method to do so would
1740 * be to look up old_dir/old_name, create a link to new_dir/new_name and
1741 * rename the old file using the sillyrename stuff. This way, the original
1742 * file in old_dir will go away when the last process iput()s the inode.
1746 * It actually works quite well. One needs to have the possibility for
1747 * at least one ".nfs..." file in each directory the file ever gets
1748 * moved or linked to which happens automagically with the new
1749 * implementation that only depends on the dcache stuff instead of
1750 * using the inode layer
1752 * Unfortunately, things are a little more complicated than indicated
1753 * above. For a cross-directory move, we want to make sure we can get
1754 * rid of the old inode after the operation. This means there must be
1755 * no pending writes (if it's a file), and the use count must be 1.
1756 * If these conditions are met, we can drop the dentries before doing
1759 static int nfs_rename(struct inode
*old_dir
, struct dentry
*old_dentry
,
1760 struct inode
*new_dir
, struct dentry
*new_dentry
)
1762 struct inode
*old_inode
= old_dentry
->d_inode
;
1763 struct inode
*new_inode
= new_dentry
->d_inode
;
1764 struct dentry
*dentry
= NULL
, *rehash
= NULL
;
1767 dfprintk(VFS
, "NFS: rename(%s/%s -> %s/%s, ct=%d)\n",
1768 old_dentry
->d_parent
->d_name
.name
, old_dentry
->d_name
.name
,
1769 new_dentry
->d_parent
->d_name
.name
, new_dentry
->d_name
.name
,
1770 atomic_read(&new_dentry
->d_count
));
1773 * For non-directories, check whether the target is busy and if so,
1774 * make a copy of the dentry and then do a silly-rename. If the
1775 * silly-rename succeeds, the copied dentry is hashed and becomes
1778 if (new_inode
&& !S_ISDIR(new_inode
->i_mode
)) {
1780 * To prevent any new references to the target during the
1781 * rename, we unhash the dentry in advance.
1783 if (!d_unhashed(new_dentry
)) {
1785 rehash
= new_dentry
;
1788 if (atomic_read(&new_dentry
->d_count
) > 2) {
1791 /* copy the target dentry's name */
1792 dentry
= d_alloc(new_dentry
->d_parent
,
1793 &new_dentry
->d_name
);
1797 /* silly-rename the existing target ... */
1798 err
= nfs_sillyrename(new_dir
, new_dentry
);
1802 new_dentry
= dentry
;
1808 nfs_inode_return_delegation(old_inode
);
1809 if (new_inode
!= NULL
)
1810 nfs_inode_return_delegation(new_inode
);
1812 error
= NFS_PROTO(old_dir
)->rename(old_dir
, &old_dentry
->d_name
,
1813 new_dir
, &new_dentry
->d_name
);
1814 nfs_mark_for_revalidate(old_inode
);
1819 if (new_inode
!= NULL
)
1820 nfs_drop_nlink(new_inode
);
1821 d_move(old_dentry
, new_dentry
);
1822 nfs_set_verifier(new_dentry
,
1823 nfs_save_change_attribute(new_dir
));
1824 } else if (error
== -ENOENT
)
1825 nfs_dentry_handle_enoent(old_dentry
);
1827 /* new dentry created? */
1833 static DEFINE_SPINLOCK(nfs_access_lru_lock
);
1834 static LIST_HEAD(nfs_access_lru_list
);
1835 static atomic_long_t nfs_access_nr_entries
;
1837 static void nfs_access_free_entry(struct nfs_access_entry
*entry
)
1839 put_rpccred(entry
->cred
);
1841 smp_mb__before_atomic_dec();
1842 atomic_long_dec(&nfs_access_nr_entries
);
1843 smp_mb__after_atomic_dec();
1846 static void nfs_access_free_list(struct list_head
*head
)
1848 struct nfs_access_entry
*cache
;
1850 while (!list_empty(head
)) {
1851 cache
= list_entry(head
->next
, struct nfs_access_entry
, lru
);
1852 list_del(&cache
->lru
);
1853 nfs_access_free_entry(cache
);
1857 int nfs_access_cache_shrinker(struct shrinker
*shrink
, int nr_to_scan
, gfp_t gfp_mask
)
1860 struct nfs_inode
*nfsi
;
1861 struct nfs_access_entry
*cache
;
1863 if ((gfp_mask
& GFP_KERNEL
) != GFP_KERNEL
)
1864 return (nr_to_scan
== 0) ? 0 : -1;
1866 spin_lock(&nfs_access_lru_lock
);
1867 list_for_each_entry(nfsi
, &nfs_access_lru_list
, access_cache_inode_lru
) {
1868 struct inode
*inode
;
1870 if (nr_to_scan
-- == 0)
1872 inode
= &nfsi
->vfs_inode
;
1873 spin_lock(&inode
->i_lock
);
1874 if (list_empty(&nfsi
->access_cache_entry_lru
))
1875 goto remove_lru_entry
;
1876 cache
= list_entry(nfsi
->access_cache_entry_lru
.next
,
1877 struct nfs_access_entry
, lru
);
1878 list_move(&cache
->lru
, &head
);
1879 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
1880 if (!list_empty(&nfsi
->access_cache_entry_lru
))
1881 list_move_tail(&nfsi
->access_cache_inode_lru
,
1882 &nfs_access_lru_list
);
1885 list_del_init(&nfsi
->access_cache_inode_lru
);
1886 smp_mb__before_clear_bit();
1887 clear_bit(NFS_INO_ACL_LRU_SET
, &nfsi
->flags
);
1888 smp_mb__after_clear_bit();
1890 spin_unlock(&inode
->i_lock
);
1892 spin_unlock(&nfs_access_lru_lock
);
1893 nfs_access_free_list(&head
);
1894 return (atomic_long_read(&nfs_access_nr_entries
) / 100) * sysctl_vfs_cache_pressure
;
1897 static void __nfs_access_zap_cache(struct nfs_inode
*nfsi
, struct list_head
*head
)
1899 struct rb_root
*root_node
= &nfsi
->access_cache
;
1901 struct nfs_access_entry
*entry
;
1903 /* Unhook entries from the cache */
1904 while ((n
= rb_first(root_node
)) != NULL
) {
1905 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
1906 rb_erase(n
, root_node
);
1907 list_move(&entry
->lru
, head
);
1909 nfsi
->cache_validity
&= ~NFS_INO_INVALID_ACCESS
;
1912 void nfs_access_zap_cache(struct inode
*inode
)
1916 if (test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
) == 0)
1918 /* Remove from global LRU init */
1919 spin_lock(&nfs_access_lru_lock
);
1920 if (test_and_clear_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
1921 list_del_init(&NFS_I(inode
)->access_cache_inode_lru
);
1923 spin_lock(&inode
->i_lock
);
1924 __nfs_access_zap_cache(NFS_I(inode
), &head
);
1925 spin_unlock(&inode
->i_lock
);
1926 spin_unlock(&nfs_access_lru_lock
);
1927 nfs_access_free_list(&head
);
1930 static struct nfs_access_entry
*nfs_access_search_rbtree(struct inode
*inode
, struct rpc_cred
*cred
)
1932 struct rb_node
*n
= NFS_I(inode
)->access_cache
.rb_node
;
1933 struct nfs_access_entry
*entry
;
1936 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
1938 if (cred
< entry
->cred
)
1940 else if (cred
> entry
->cred
)
1948 static int nfs_access_get_cached(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_access_entry
*res
)
1950 struct nfs_inode
*nfsi
= NFS_I(inode
);
1951 struct nfs_access_entry
*cache
;
1954 spin_lock(&inode
->i_lock
);
1955 if (nfsi
->cache_validity
& NFS_INO_INVALID_ACCESS
)
1957 cache
= nfs_access_search_rbtree(inode
, cred
);
1960 if (!nfs_have_delegated_attributes(inode
) &&
1961 !time_in_range_open(jiffies
, cache
->jiffies
, cache
->jiffies
+ nfsi
->attrtimeo
))
1963 res
->jiffies
= cache
->jiffies
;
1964 res
->cred
= cache
->cred
;
1965 res
->mask
= cache
->mask
;
1966 list_move_tail(&cache
->lru
, &nfsi
->access_cache_entry_lru
);
1969 spin_unlock(&inode
->i_lock
);
1972 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
1973 list_del(&cache
->lru
);
1974 spin_unlock(&inode
->i_lock
);
1975 nfs_access_free_entry(cache
);
1978 spin_unlock(&inode
->i_lock
);
1979 nfs_access_zap_cache(inode
);
1983 static void nfs_access_add_rbtree(struct inode
*inode
, struct nfs_access_entry
*set
)
1985 struct nfs_inode
*nfsi
= NFS_I(inode
);
1986 struct rb_root
*root_node
= &nfsi
->access_cache
;
1987 struct rb_node
**p
= &root_node
->rb_node
;
1988 struct rb_node
*parent
= NULL
;
1989 struct nfs_access_entry
*entry
;
1991 spin_lock(&inode
->i_lock
);
1992 while (*p
!= NULL
) {
1994 entry
= rb_entry(parent
, struct nfs_access_entry
, rb_node
);
1996 if (set
->cred
< entry
->cred
)
1997 p
= &parent
->rb_left
;
1998 else if (set
->cred
> entry
->cred
)
1999 p
= &parent
->rb_right
;
2003 rb_link_node(&set
->rb_node
, parent
, p
);
2004 rb_insert_color(&set
->rb_node
, root_node
);
2005 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2006 spin_unlock(&inode
->i_lock
);
2009 rb_replace_node(parent
, &set
->rb_node
, root_node
);
2010 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
2011 list_del(&entry
->lru
);
2012 spin_unlock(&inode
->i_lock
);
2013 nfs_access_free_entry(entry
);
2016 static void nfs_access_add_cache(struct inode
*inode
, struct nfs_access_entry
*set
)
2018 struct nfs_access_entry
*cache
= kmalloc(sizeof(*cache
), GFP_KERNEL
);
2021 RB_CLEAR_NODE(&cache
->rb_node
);
2022 cache
->jiffies
= set
->jiffies
;
2023 cache
->cred
= get_rpccred(set
->cred
);
2024 cache
->mask
= set
->mask
;
2026 nfs_access_add_rbtree(inode
, cache
);
2028 /* Update accounting */
2029 smp_mb__before_atomic_inc();
2030 atomic_long_inc(&nfs_access_nr_entries
);
2031 smp_mb__after_atomic_inc();
2033 /* Add inode to global LRU list */
2034 if (!test_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
)) {
2035 spin_lock(&nfs_access_lru_lock
);
2036 if (!test_and_set_bit(NFS_INO_ACL_LRU_SET
, &NFS_I(inode
)->flags
))
2037 list_add_tail(&NFS_I(inode
)->access_cache_inode_lru
,
2038 &nfs_access_lru_list
);
2039 spin_unlock(&nfs_access_lru_lock
);
2043 static int nfs_do_access(struct inode
*inode
, struct rpc_cred
*cred
, int mask
)
2045 struct nfs_access_entry cache
;
2048 status
= nfs_access_get_cached(inode
, cred
, &cache
);
2052 /* Be clever: ask server to check for all possible rights */
2053 cache
.mask
= MAY_EXEC
| MAY_WRITE
| MAY_READ
;
2055 cache
.jiffies
= jiffies
;
2056 status
= NFS_PROTO(inode
)->access(inode
, &cache
);
2058 if (status
== -ESTALE
) {
2059 nfs_zap_caches(inode
);
2060 if (!S_ISDIR(inode
->i_mode
))
2061 set_bit(NFS_INO_STALE
, &NFS_I(inode
)->flags
);
2065 nfs_access_add_cache(inode
, &cache
);
2067 if ((mask
& ~cache
.mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) == 0)
2072 static int nfs_open_permission_mask(int openflags
)
2076 if (openflags
& FMODE_READ
)
2078 if (openflags
& FMODE_WRITE
)
2080 if (openflags
& FMODE_EXEC
)
2085 int nfs_may_open(struct inode
*inode
, struct rpc_cred
*cred
, int openflags
)
2087 return nfs_do_access(inode
, cred
, nfs_open_permission_mask(openflags
));
2090 int nfs_permission(struct inode
*inode
, int mask
)
2092 struct rpc_cred
*cred
;
2095 nfs_inc_stats(inode
, NFSIOS_VFSACCESS
);
2097 if ((mask
& (MAY_READ
| MAY_WRITE
| MAY_EXEC
)) == 0)
2099 /* Is this sys_access() ? */
2100 if (mask
& (MAY_ACCESS
| MAY_CHDIR
))
2103 switch (inode
->i_mode
& S_IFMT
) {
2107 /* NFSv4 has atomic_open... */
2108 if (nfs_server_capable(inode
, NFS_CAP_ATOMIC_OPEN
)
2109 && (mask
& MAY_OPEN
)
2110 && !(mask
& MAY_EXEC
))
2115 * Optimize away all write operations, since the server
2116 * will check permissions when we perform the op.
2118 if ((mask
& MAY_WRITE
) && !(mask
& MAY_READ
))
2123 if (!NFS_PROTO(inode
)->access
)
2126 cred
= rpc_lookup_cred();
2127 if (!IS_ERR(cred
)) {
2128 res
= nfs_do_access(inode
, cred
, mask
);
2131 res
= PTR_ERR(cred
);
2133 if (!res
&& (mask
& MAY_EXEC
) && !execute_ok(inode
))
2136 dfprintk(VFS
, "NFS: permission(%s/%ld), mask=0x%x, res=%d\n",
2137 inode
->i_sb
->s_id
, inode
->i_ino
, mask
, res
);
2140 res
= nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
2142 res
= generic_permission(inode
, mask
, NULL
);
2148 * version-control: t
2149 * kept-new-versions: 5