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/smp_lock.h>
33 #include <linux/pagevec.h>
34 #include <linux/namei.h>
35 #include <linux/mount.h>
36 #include <linux/sched.h>
39 #include "delegation.h"
42 /* #define NFS_DEBUG_VERBOSE 1 */
44 static int nfs_opendir(struct inode
*, struct file
*);
45 static int nfs_readdir(struct file
*, void *, filldir_t
);
46 static struct dentry
*nfs_lookup(struct inode
*, struct dentry
*, struct nameidata
*);
47 static int nfs_create(struct inode
*, struct dentry
*, int, struct nameidata
*);
48 static int nfs_mkdir(struct inode
*, struct dentry
*, int);
49 static int nfs_rmdir(struct inode
*, struct dentry
*);
50 static int nfs_unlink(struct inode
*, struct dentry
*);
51 static int nfs_symlink(struct inode
*, struct dentry
*, const char *);
52 static int nfs_link(struct dentry
*, struct inode
*, struct dentry
*);
53 static int nfs_mknod(struct inode
*, struct dentry
*, int, dev_t
);
54 static int nfs_rename(struct inode
*, struct dentry
*,
55 struct inode
*, struct dentry
*);
56 static int nfs_fsync_dir(struct file
*, struct dentry
*, int);
57 static loff_t
nfs_llseek_dir(struct file
*, loff_t
, int);
59 const struct file_operations nfs_dir_operations
= {
60 .llseek
= nfs_llseek_dir
,
61 .read
= generic_read_dir
,
62 .readdir
= nfs_readdir
,
64 .release
= nfs_release
,
65 .fsync
= nfs_fsync_dir
,
68 const struct inode_operations nfs_dir_inode_operations
= {
73 .symlink
= nfs_symlink
,
78 .permission
= nfs_permission
,
79 .getattr
= nfs_getattr
,
80 .setattr
= nfs_setattr
,
84 const struct inode_operations nfs3_dir_inode_operations
= {
89 .symlink
= nfs_symlink
,
94 .permission
= nfs_permission
,
95 .getattr
= nfs_getattr
,
96 .setattr
= nfs_setattr
,
97 .listxattr
= nfs3_listxattr
,
98 .getxattr
= nfs3_getxattr
,
99 .setxattr
= nfs3_setxattr
,
100 .removexattr
= nfs3_removexattr
,
102 #endif /* CONFIG_NFS_V3 */
106 static struct dentry
*nfs_atomic_lookup(struct inode
*, struct dentry
*, struct nameidata
*);
107 const struct inode_operations nfs4_dir_inode_operations
= {
108 .create
= nfs_create
,
109 .lookup
= nfs_atomic_lookup
,
111 .unlink
= nfs_unlink
,
112 .symlink
= nfs_symlink
,
116 .rename
= nfs_rename
,
117 .permission
= nfs_permission
,
118 .getattr
= nfs_getattr
,
119 .setattr
= nfs_setattr
,
120 .getxattr
= nfs4_getxattr
,
121 .setxattr
= nfs4_setxattr
,
122 .listxattr
= nfs4_listxattr
,
125 #endif /* CONFIG_NFS_V4 */
131 nfs_opendir(struct inode
*inode
, struct file
*filp
)
135 dfprintk(VFS
, "NFS: opendir(%s/%ld)\n",
136 inode
->i_sb
->s_id
, inode
->i_ino
);
139 /* Call generic open code in order to cache credentials */
140 res
= nfs_open(inode
, filp
);
145 typedef __be32
* (*decode_dirent_t
)(__be32
*, struct nfs_entry
*, int);
149 unsigned long page_index
;
152 loff_t current_index
;
153 struct nfs_entry
*entry
;
154 decode_dirent_t decode
;
157 unsigned long timestamp
;
159 } nfs_readdir_descriptor_t
;
161 /* Now we cache directories properly, by stuffing the dirent
162 * data directly in the page cache.
164 * Inode invalidation due to refresh etc. takes care of
165 * _everything_, no sloppy entry flushing logic, no extraneous
166 * copying, network direct to page cache, the way it was meant
169 * NOTE: Dirent information verification is done always by the
170 * page-in of the RPC reply, nowhere else, this simplies
171 * things substantially.
174 int nfs_readdir_filler(nfs_readdir_descriptor_t
*desc
, struct page
*page
)
176 struct file
*file
= desc
->file
;
177 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
178 struct rpc_cred
*cred
= nfs_file_cred(file
);
179 unsigned long timestamp
;
182 dfprintk(DIRCACHE
, "NFS: %s: reading cookie %Lu into page %lu\n",
183 __FUNCTION__
, (long long)desc
->entry
->cookie
,
188 error
= NFS_PROTO(inode
)->readdir(file
->f_path
.dentry
, cred
, desc
->entry
->cookie
, page
,
189 NFS_SERVER(inode
)->dtsize
, desc
->plus
);
191 /* We requested READDIRPLUS, but the server doesn't grok it */
192 if (error
== -ENOTSUPP
&& desc
->plus
) {
193 NFS_SERVER(inode
)->caps
&= ~NFS_CAP_READDIRPLUS
;
194 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_FLAGS(inode
));
200 desc
->timestamp
= timestamp
;
201 desc
->timestamp_valid
= 1;
202 SetPageUptodate(page
);
203 /* Ensure consistent page alignment of the data.
204 * Note: assumes we have exclusive access to this mapping either
205 * through inode->i_mutex or some other mechanism.
207 if (page
->index
== 0 && invalidate_inode_pages2_range(inode
->i_mapping
, PAGE_CACHE_SIZE
, -1) < 0) {
208 /* Should never happen */
209 nfs_zap_mapping(inode
, inode
->i_mapping
);
216 nfs_zap_caches(inode
);
222 int dir_decode(nfs_readdir_descriptor_t
*desc
)
224 __be32
*p
= desc
->ptr
;
225 p
= desc
->decode(p
, desc
->entry
, desc
->plus
);
229 if (desc
->timestamp_valid
)
230 desc
->entry
->fattr
->time_start
= desc
->timestamp
;
232 desc
->entry
->fattr
->valid
&= ~NFS_ATTR_FATTR
;
237 void dir_page_release(nfs_readdir_descriptor_t
*desc
)
240 page_cache_release(desc
->page
);
246 * Given a pointer to a buffer that has already been filled by a call
247 * to readdir, find the next entry with cookie '*desc->dir_cookie'.
249 * If the end of the buffer has been reached, return -EAGAIN, if not,
250 * return the offset within the buffer of the next entry to be
254 int find_dirent(nfs_readdir_descriptor_t
*desc
)
256 struct nfs_entry
*entry
= desc
->entry
;
260 while((status
= dir_decode(desc
)) == 0) {
261 dfprintk(DIRCACHE
, "NFS: %s: examining cookie %Lu\n",
262 __FUNCTION__
, (unsigned long long)entry
->cookie
);
263 if (entry
->prev_cookie
== *desc
->dir_cookie
)
265 if (loop_count
++ > 200) {
274 * Given a pointer to a buffer that has already been filled by a call
275 * to readdir, find the entry at offset 'desc->file->f_pos'.
277 * If the end of the buffer has been reached, return -EAGAIN, if not,
278 * return the offset within the buffer of the next entry to be
282 int find_dirent_index(nfs_readdir_descriptor_t
*desc
)
284 struct nfs_entry
*entry
= desc
->entry
;
289 status
= dir_decode(desc
);
293 dfprintk(DIRCACHE
, "NFS: found cookie %Lu at index %Ld\n",
294 (unsigned long long)entry
->cookie
, desc
->current_index
);
296 if (desc
->file
->f_pos
== desc
->current_index
) {
297 *desc
->dir_cookie
= entry
->cookie
;
300 desc
->current_index
++;
301 if (loop_count
++ > 200) {
310 * Find the given page, and call find_dirent() or find_dirent_index in
311 * order to try to return the next entry.
314 int find_dirent_page(nfs_readdir_descriptor_t
*desc
)
316 struct inode
*inode
= desc
->file
->f_path
.dentry
->d_inode
;
320 dfprintk(DIRCACHE
, "NFS: %s: searching page %ld for target %Lu\n",
321 __FUNCTION__
, desc
->page_index
,
322 (long long) *desc
->dir_cookie
);
324 /* If we find the page in the page_cache, we cannot be sure
325 * how fresh the data is, so we will ignore readdir_plus attributes.
327 desc
->timestamp_valid
= 0;
328 page
= read_cache_page(inode
->i_mapping
, desc
->page_index
,
329 (filler_t
*)nfs_readdir_filler
, desc
);
331 status
= PTR_ERR(page
);
335 /* NOTE: Someone else may have changed the READDIRPLUS flag */
337 desc
->ptr
= kmap(page
); /* matching kunmap in nfs_do_filldir */
338 if (*desc
->dir_cookie
!= 0)
339 status
= find_dirent(desc
);
341 status
= find_dirent_index(desc
);
343 dir_page_release(desc
);
345 dfprintk(DIRCACHE
, "NFS: %s: returns %d\n", __FUNCTION__
, status
);
350 * Recurse through the page cache pages, and return a
351 * filled nfs_entry structure of the next directory entry if possible.
353 * The target for the search is '*desc->dir_cookie' if non-0,
354 * 'desc->file->f_pos' otherwise
357 int readdir_search_pagecache(nfs_readdir_descriptor_t
*desc
)
362 /* Always search-by-index from the beginning of the cache */
363 if (*desc
->dir_cookie
== 0) {
364 dfprintk(DIRCACHE
, "NFS: readdir_search_pagecache() searching for offset %Ld\n",
365 (long long)desc
->file
->f_pos
);
366 desc
->page_index
= 0;
367 desc
->entry
->cookie
= desc
->entry
->prev_cookie
= 0;
368 desc
->entry
->eof
= 0;
369 desc
->current_index
= 0;
371 dfprintk(DIRCACHE
, "NFS: readdir_search_pagecache() searching for cookie %Lu\n",
372 (unsigned long long)*desc
->dir_cookie
);
375 res
= find_dirent_page(desc
);
378 /* Align to beginning of next page */
380 if (loop_count
++ > 200) {
386 dfprintk(DIRCACHE
, "NFS: %s: returns %d\n", __FUNCTION__
, res
);
390 static inline unsigned int dt_type(struct inode
*inode
)
392 return (inode
->i_mode
>> 12) & 15;
395 static struct dentry
*nfs_readdir_lookup(nfs_readdir_descriptor_t
*desc
);
398 * Once we've found the start of the dirent within a page: fill 'er up...
401 int nfs_do_filldir(nfs_readdir_descriptor_t
*desc
, void *dirent
,
404 struct file
*file
= desc
->file
;
405 struct nfs_entry
*entry
= desc
->entry
;
406 struct dentry
*dentry
= NULL
;
411 dfprintk(DIRCACHE
, "NFS: nfs_do_filldir() filling starting @ cookie %Lu\n",
412 (unsigned long long)entry
->cookie
);
415 unsigned d_type
= DT_UNKNOWN
;
416 /* Note: entry->prev_cookie contains the cookie for
417 * retrieving the current dirent on the server */
420 /* Get a dentry if we have one */
423 dentry
= nfs_readdir_lookup(desc
);
425 /* Use readdirplus info */
426 if (dentry
!= NULL
&& dentry
->d_inode
!= NULL
) {
427 d_type
= dt_type(dentry
->d_inode
);
428 fileid
= NFS_FILEID(dentry
->d_inode
);
431 res
= filldir(dirent
, entry
->name
, entry
->len
,
432 file
->f_pos
, fileid
, d_type
);
436 *desc
->dir_cookie
= entry
->cookie
;
437 if (dir_decode(desc
) != 0) {
441 if (loop_count
++ > 200) {
446 dir_page_release(desc
);
449 dfprintk(DIRCACHE
, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n",
450 (unsigned long long)*desc
->dir_cookie
, res
);
455 * If we cannot find a cookie in our cache, we suspect that this is
456 * because it points to a deleted file, so we ask the server to return
457 * whatever it thinks is the next entry. We then feed this to filldir.
458 * If all goes well, we should then be able to find our way round the
459 * cache on the next call to readdir_search_pagecache();
461 * NOTE: we cannot add the anonymous page to the pagecache because
462 * the data it contains might not be page aligned. Besides,
463 * we should already have a complete representation of the
464 * directory in the page cache by the time we get here.
467 int uncached_readdir(nfs_readdir_descriptor_t
*desc
, void *dirent
,
470 struct file
*file
= desc
->file
;
471 struct inode
*inode
= file
->f_path
.dentry
->d_inode
;
472 struct rpc_cred
*cred
= nfs_file_cred(file
);
473 struct page
*page
= NULL
;
475 unsigned long timestamp
;
477 dfprintk(DIRCACHE
, "NFS: uncached_readdir() searching for cookie %Lu\n",
478 (unsigned long long)*desc
->dir_cookie
);
480 page
= alloc_page(GFP_HIGHUSER
);
486 desc
->error
= NFS_PROTO(inode
)->readdir(file
->f_path
.dentry
, cred
, *desc
->dir_cookie
,
488 NFS_SERVER(inode
)->dtsize
,
491 desc
->ptr
= kmap(page
); /* matching kunmap in nfs_do_filldir */
492 if (desc
->error
>= 0) {
493 desc
->timestamp
= timestamp
;
494 desc
->timestamp_valid
= 1;
495 if ((status
= dir_decode(desc
)) == 0)
496 desc
->entry
->prev_cookie
= *desc
->dir_cookie
;
502 status
= nfs_do_filldir(desc
, dirent
, filldir
);
504 /* Reset read descriptor so it searches the page cache from
505 * the start upon the next call to readdir_search_pagecache() */
506 desc
->page_index
= 0;
507 desc
->entry
->cookie
= desc
->entry
->prev_cookie
= 0;
508 desc
->entry
->eof
= 0;
510 dfprintk(DIRCACHE
, "NFS: %s: returns %d\n",
511 __FUNCTION__
, status
);
514 dir_page_release(desc
);
518 /* The file offset position represents the dirent entry number. A
519 last cookie cache takes care of the common case of reading the
522 static int nfs_readdir(struct file
*filp
, void *dirent
, filldir_t filldir
)
524 struct dentry
*dentry
= filp
->f_path
.dentry
;
525 struct inode
*inode
= dentry
->d_inode
;
526 nfs_readdir_descriptor_t my_desc
,
528 struct nfs_entry my_entry
;
530 struct nfs_fattr fattr
;
533 dfprintk(VFS
, "NFS: readdir(%s/%s) starting at cookie %Lu\n",
534 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
535 (long long)filp
->f_pos
);
536 nfs_inc_stats(inode
, NFSIOS_VFSGETDENTS
);
540 res
= nfs_revalidate_mapping_nolock(inode
, filp
->f_mapping
);
547 * filp->f_pos points to the dirent entry number.
548 * *desc->dir_cookie has the cookie for the next entry. We have
549 * to either find the entry with the appropriate number or
550 * revalidate the cookie.
552 memset(desc
, 0, sizeof(*desc
));
555 desc
->dir_cookie
= &nfs_file_open_context(filp
)->dir_cookie
;
556 desc
->decode
= NFS_PROTO(inode
)->decode_dirent
;
557 desc
->plus
= NFS_USE_READDIRPLUS(inode
);
559 my_entry
.cookie
= my_entry
.prev_cookie
= 0;
562 my_entry
.fattr
= &fattr
;
563 nfs_fattr_init(&fattr
);
564 desc
->entry
= &my_entry
;
566 while(!desc
->entry
->eof
) {
567 res
= readdir_search_pagecache(desc
);
569 if (res
== -EBADCOOKIE
) {
570 /* This means either end of directory */
571 if (*desc
->dir_cookie
&& desc
->entry
->cookie
!= *desc
->dir_cookie
) {
572 /* Or that the server has 'lost' a cookie */
573 res
= uncached_readdir(desc
, dirent
, filldir
);
580 if (res
== -ETOOSMALL
&& desc
->plus
) {
581 clear_bit(NFS_INO_ADVISE_RDPLUS
, &NFS_FLAGS(inode
));
582 nfs_zap_caches(inode
);
584 desc
->entry
->eof
= 0;
590 res
= nfs_do_filldir(desc
, dirent
, filldir
);
599 dfprintk(VFS
, "NFS: readdir(%s/%s) returns %ld\n",
600 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
605 static loff_t
nfs_llseek_dir(struct file
*filp
, loff_t offset
, int origin
)
607 mutex_lock(&filp
->f_path
.dentry
->d_inode
->i_mutex
);
610 offset
+= filp
->f_pos
;
618 if (offset
!= filp
->f_pos
) {
619 filp
->f_pos
= offset
;
620 nfs_file_open_context(filp
)->dir_cookie
= 0;
623 mutex_unlock(&filp
->f_path
.dentry
->d_inode
->i_mutex
);
628 * All directory operations under NFS are synchronous, so fsync()
629 * is a dummy operation.
631 static int nfs_fsync_dir(struct file
*filp
, struct dentry
*dentry
, int datasync
)
633 dfprintk(VFS
, "NFS: fsync_dir(%s/%s) datasync %d\n",
634 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
641 * A check for whether or not the parent directory has changed.
642 * In the case it has, we assume that the dentries are untrustworthy
643 * and may need to be looked up again.
645 static int nfs_check_verifier(struct inode
*dir
, struct dentry
*dentry
)
649 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
651 /* Revalidate nfsi->cache_change_attribute before we declare a match */
652 if (nfs_revalidate_inode(NFS_SERVER(dir
), dir
) < 0)
654 if (!nfs_verify_change_attribute(dir
, dentry
->d_time
))
659 static inline void nfs_set_verifier(struct dentry
* dentry
, unsigned long verf
)
661 dentry
->d_time
= verf
;
665 * Return the intent data that applies to this particular path component
667 * Note that the current set of intents only apply to the very last
668 * component of the path.
669 * We check for this using LOOKUP_CONTINUE and LOOKUP_PARENT.
671 static inline unsigned int nfs_lookup_check_intent(struct nameidata
*nd
, unsigned int mask
)
673 if (nd
->flags
& (LOOKUP_CONTINUE
|LOOKUP_PARENT
))
675 return nd
->flags
& mask
;
679 * Inode and filehandle revalidation for lookups.
681 * We force revalidation in the cases where the VFS sets LOOKUP_REVAL,
682 * or if the intent information indicates that we're about to open this
683 * particular file and the "nocto" mount flag is not set.
687 int nfs_lookup_verify_inode(struct inode
*inode
, struct nameidata
*nd
)
689 struct nfs_server
*server
= NFS_SERVER(inode
);
692 /* VFS wants an on-the-wire revalidation */
693 if (nd
->flags
& LOOKUP_REVAL
)
695 /* This is an open(2) */
696 if (nfs_lookup_check_intent(nd
, LOOKUP_OPEN
) != 0 &&
697 !(server
->flags
& NFS_MOUNT_NOCTO
) &&
698 (S_ISREG(inode
->i_mode
) ||
699 S_ISDIR(inode
->i_mode
)))
702 return nfs_revalidate_inode(server
, inode
);
704 return __nfs_revalidate_inode(server
, inode
);
708 * We judge how long we want to trust negative
709 * dentries by looking at the parent inode mtime.
711 * If parent mtime has changed, we revalidate, else we wait for a
712 * period corresponding to the parent's attribute cache timeout value.
715 int nfs_neg_need_reval(struct inode
*dir
, struct dentry
*dentry
,
716 struct nameidata
*nd
)
718 /* Don't revalidate a negative dentry if we're creating a new file */
719 if (nd
!= NULL
&& nfs_lookup_check_intent(nd
, LOOKUP_CREATE
) != 0)
721 return !nfs_check_verifier(dir
, dentry
);
725 * This is called every time the dcache has a lookup hit,
726 * and we should check whether we can really trust that
729 * NOTE! The hit can be a negative hit too, don't assume
732 * If the parent directory is seen to have changed, we throw out the
733 * cached dentry and do a new lookup.
735 static int nfs_lookup_revalidate(struct dentry
* dentry
, struct nameidata
*nd
)
739 struct dentry
*parent
;
741 struct nfs_fh fhandle
;
742 struct nfs_fattr fattr
;
744 parent
= dget_parent(dentry
);
746 dir
= parent
->d_inode
;
747 nfs_inc_stats(dir
, NFSIOS_DENTRYREVALIDATE
);
748 inode
= dentry
->d_inode
;
751 if (nfs_neg_need_reval(dir
, dentry
, nd
))
756 if (is_bad_inode(inode
)) {
757 dfprintk(LOOKUPCACHE
, "%s: %s/%s has dud inode\n",
758 __FUNCTION__
, dentry
->d_parent
->d_name
.name
,
759 dentry
->d_name
.name
);
763 /* Force a full look up iff the parent directory has changed */
764 if (nfs_check_verifier(dir
, dentry
)) {
765 if (nfs_lookup_verify_inode(inode
, nd
))
770 if (NFS_STALE(inode
))
773 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, &fhandle
, &fattr
);
776 if (nfs_compare_fh(NFS_FH(inode
), &fhandle
))
778 if ((error
= nfs_refresh_inode(inode
, &fattr
)) != 0)
781 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
785 dfprintk(LOOKUPCACHE
, "NFS: %s(%s/%s) is valid\n",
786 __FUNCTION__
, dentry
->d_parent
->d_name
.name
,
787 dentry
->d_name
.name
);
792 nfs_mark_for_revalidate(dir
);
793 if (inode
&& S_ISDIR(inode
->i_mode
)) {
794 /* Purge readdir caches. */
795 nfs_zap_caches(inode
);
796 /* If we have submounts, don't unhash ! */
797 if (have_submounts(dentry
))
799 shrink_dcache_parent(dentry
);
804 dfprintk(LOOKUPCACHE
, "NFS: %s(%s/%s) is invalid\n",
805 __FUNCTION__
, dentry
->d_parent
->d_name
.name
,
806 dentry
->d_name
.name
);
811 * This is called from dput() when d_count is going to 0.
813 static int nfs_dentry_delete(struct dentry
*dentry
)
815 dfprintk(VFS
, "NFS: dentry_delete(%s/%s, %x)\n",
816 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
819 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
820 /* Unhash it, so that ->d_iput() would be called */
823 if (!(dentry
->d_sb
->s_flags
& MS_ACTIVE
)) {
824 /* Unhash it, so that ancestors of killed async unlink
825 * files will be cleaned up during umount */
833 * Called when the dentry loses inode.
834 * We use it to clean up silly-renamed files.
836 static void nfs_dentry_iput(struct dentry
*dentry
, struct inode
*inode
)
838 nfs_inode_return_delegation(inode
);
839 if (S_ISDIR(inode
->i_mode
))
840 /* drop any readdir cache as it could easily be old */
841 NFS_I(inode
)->cache_validity
|= NFS_INO_INVALID_DATA
;
843 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
846 nfs_complete_unlink(dentry
, inode
);
852 struct dentry_operations nfs_dentry_operations
= {
853 .d_revalidate
= nfs_lookup_revalidate
,
854 .d_delete
= nfs_dentry_delete
,
855 .d_iput
= nfs_dentry_iput
,
859 * Use intent information to check whether or not we're going to do
860 * an O_EXCL create using this path component.
863 int nfs_is_exclusive_create(struct inode
*dir
, struct nameidata
*nd
)
865 if (NFS_PROTO(dir
)->version
== 2)
867 if (nd
== NULL
|| nfs_lookup_check_intent(nd
, LOOKUP_CREATE
) == 0)
869 return (nd
->intent
.open
.flags
& O_EXCL
) != 0;
872 static inline int nfs_reval_fsid(struct inode
*dir
, const struct nfs_fattr
*fattr
)
874 struct nfs_server
*server
= NFS_SERVER(dir
);
876 if (!nfs_fsid_equal(&server
->fsid
, &fattr
->fsid
))
877 /* Revalidate fsid using the parent directory */
878 return __nfs_revalidate_inode(server
, dir
);
882 static struct dentry
*nfs_lookup(struct inode
*dir
, struct dentry
* dentry
, struct nameidata
*nd
)
885 struct inode
*inode
= NULL
;
887 struct nfs_fh fhandle
;
888 struct nfs_fattr fattr
;
890 dfprintk(VFS
, "NFS: lookup(%s/%s)\n",
891 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
892 nfs_inc_stats(dir
, NFSIOS_VFSLOOKUP
);
894 res
= ERR_PTR(-ENAMETOOLONG
);
895 if (dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
)
898 res
= ERR_PTR(-ENOMEM
);
899 dentry
->d_op
= NFS_PROTO(dir
)->dentry_ops
;
904 * If we're doing an exclusive create, optimize away the lookup
905 * but don't hash the dentry.
907 if (nfs_is_exclusive_create(dir
, nd
)) {
908 d_instantiate(dentry
, NULL
);
913 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, &fhandle
, &fattr
);
914 if (error
== -ENOENT
)
917 res
= ERR_PTR(error
);
920 error
= nfs_reval_fsid(dir
, &fattr
);
922 res
= ERR_PTR(error
);
925 inode
= nfs_fhget(dentry
->d_sb
, &fhandle
, &fattr
);
926 res
= (struct dentry
*)inode
;
931 res
= d_materialise_unique(dentry
, inode
);
937 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
945 static int nfs_open_revalidate(struct dentry
*, struct nameidata
*);
947 struct dentry_operations nfs4_dentry_operations
= {
948 .d_revalidate
= nfs_open_revalidate
,
949 .d_delete
= nfs_dentry_delete
,
950 .d_iput
= nfs_dentry_iput
,
954 * Use intent information to determine whether we need to substitute
955 * the NFSv4-style stateful OPEN for the LOOKUP call
957 static int is_atomic_open(struct inode
*dir
, struct nameidata
*nd
)
959 if (nd
== NULL
|| nfs_lookup_check_intent(nd
, LOOKUP_OPEN
) == 0)
961 /* NFS does not (yet) have a stateful open for directories */
962 if (nd
->flags
& LOOKUP_DIRECTORY
)
964 /* Are we trying to write to a read only partition? */
965 if (IS_RDONLY(dir
) && (nd
->intent
.open
.flags
& (O_CREAT
|O_TRUNC
|FMODE_WRITE
)))
970 static struct dentry
*nfs_atomic_lookup(struct inode
*dir
, struct dentry
*dentry
, struct nameidata
*nd
)
972 struct dentry
*res
= NULL
;
975 dfprintk(VFS
, "NFS: atomic_lookup(%s/%ld), %s\n",
976 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
978 /* Check that we are indeed trying to open this file */
979 if (!is_atomic_open(dir
, nd
))
982 if (dentry
->d_name
.len
> NFS_SERVER(dir
)->namelen
) {
983 res
= ERR_PTR(-ENAMETOOLONG
);
986 dentry
->d_op
= NFS_PROTO(dir
)->dentry_ops
;
988 /* Let vfs_create() deal with O_EXCL. Instantiate, but don't hash
990 if (nd
->intent
.open
.flags
& O_EXCL
) {
991 d_instantiate(dentry
, NULL
);
995 /* Open the file on the server */
997 res
= nfs4_atomic_open(dir
, dentry
, nd
);
1000 error
= PTR_ERR(res
);
1002 /* Make a negative dentry */
1006 /* This turned out not to be a regular file */
1011 if (!(nd
->intent
.open
.flags
& O_NOFOLLOW
))
1017 } else if (res
!= NULL
)
1019 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1023 return nfs_lookup(dir
, dentry
, nd
);
1026 static int nfs_open_revalidate(struct dentry
*dentry
, struct nameidata
*nd
)
1028 struct dentry
*parent
= NULL
;
1029 struct inode
*inode
= dentry
->d_inode
;
1031 int openflags
, ret
= 0;
1033 parent
= dget_parent(dentry
);
1034 dir
= parent
->d_inode
;
1035 if (!is_atomic_open(dir
, nd
))
1037 /* We can't create new files in nfs_open_revalidate(), so we
1038 * optimize away revalidation of negative dentries.
1042 /* NFS only supports OPEN on regular files */
1043 if (!S_ISREG(inode
->i_mode
))
1045 openflags
= nd
->intent
.open
.flags
;
1046 /* We cannot do exclusive creation on a positive dentry */
1047 if ((openflags
& (O_CREAT
|O_EXCL
)) == (O_CREAT
|O_EXCL
))
1049 /* We can't create new files, or truncate existing ones here */
1050 openflags
&= ~(O_CREAT
|O_TRUNC
);
1053 * Note: we're not holding inode->i_mutex and so may be racing with
1054 * operations that change the directory. We therefore save the
1055 * change attribute *before* we do the RPC call.
1058 ret
= nfs4_open_revalidate(dir
, dentry
, openflags
, nd
);
1060 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1069 if (inode
!= NULL
&& nfs_have_delegation(inode
, FMODE_READ
))
1071 return nfs_lookup_revalidate(dentry
, nd
);
1073 #endif /* CONFIG_NFSV4 */
1075 static struct dentry
*nfs_readdir_lookup(nfs_readdir_descriptor_t
*desc
)
1077 struct dentry
*parent
= desc
->file
->f_path
.dentry
;
1078 struct inode
*dir
= parent
->d_inode
;
1079 struct nfs_entry
*entry
= desc
->entry
;
1080 struct dentry
*dentry
, *alias
;
1081 struct qstr name
= {
1082 .name
= entry
->name
,
1085 struct inode
*inode
;
1086 unsigned long verf
= nfs_save_change_attribute(dir
);
1090 if (name
.name
[0] == '.' && name
.name
[1] == '.')
1091 return dget_parent(parent
);
1094 if (name
.name
[0] == '.')
1095 return dget(parent
);
1098 spin_lock(&dir
->i_lock
);
1099 if (NFS_I(dir
)->cache_validity
& NFS_INO_INVALID_DATA
) {
1100 spin_unlock(&dir
->i_lock
);
1103 spin_unlock(&dir
->i_lock
);
1105 name
.hash
= full_name_hash(name
.name
, name
.len
);
1106 dentry
= d_lookup(parent
, &name
);
1107 if (dentry
!= NULL
) {
1108 /* Is this a positive dentry that matches the readdir info? */
1109 if (dentry
->d_inode
!= NULL
&&
1110 (NFS_FILEID(dentry
->d_inode
) == entry
->ino
||
1111 d_mountpoint(dentry
))) {
1112 if (!desc
->plus
|| entry
->fh
->size
== 0)
1114 if (nfs_compare_fh(NFS_FH(dentry
->d_inode
),
1118 /* No, so d_drop to allow one to be created */
1122 if (!desc
->plus
|| !(entry
->fattr
->valid
& NFS_ATTR_FATTR
))
1124 if (name
.len
> NFS_SERVER(dir
)->namelen
)
1126 /* Note: caller is already holding the dir->i_mutex! */
1127 dentry
= d_alloc(parent
, &name
);
1130 dentry
->d_op
= NFS_PROTO(dir
)->dentry_ops
;
1131 inode
= nfs_fhget(dentry
->d_sb
, entry
->fh
, entry
->fattr
);
1132 if (IS_ERR(inode
)) {
1137 alias
= d_materialise_unique(dentry
, inode
);
1138 if (alias
!= NULL
) {
1146 nfs_set_verifier(dentry
, verf
);
1151 * Code common to create, mkdir, and mknod.
1153 int nfs_instantiate(struct dentry
*dentry
, struct nfs_fh
*fhandle
,
1154 struct nfs_fattr
*fattr
)
1156 struct dentry
*parent
= dget_parent(dentry
);
1157 struct inode
*dir
= parent
->d_inode
;
1158 struct inode
*inode
;
1159 int error
= -EACCES
;
1163 /* We may have been initialized further down */
1164 if (dentry
->d_inode
)
1166 if (fhandle
->size
== 0) {
1167 error
= NFS_PROTO(dir
)->lookup(dir
, &dentry
->d_name
, fhandle
, fattr
);
1171 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1172 if (!(fattr
->valid
& NFS_ATTR_FATTR
)) {
1173 struct nfs_server
*server
= NFS_SB(dentry
->d_sb
);
1174 error
= server
->nfs_client
->rpc_ops
->getattr(server
, fhandle
, fattr
);
1178 inode
= nfs_fhget(dentry
->d_sb
, fhandle
, fattr
);
1179 error
= PTR_ERR(inode
);
1182 d_add(dentry
, inode
);
1187 nfs_mark_for_revalidate(dir
);
1193 * Following a failed create operation, we drop the dentry rather
1194 * than retain a negative dentry. This avoids a problem in the event
1195 * that the operation succeeded on the server, but an error in the
1196 * reply path made it appear to have failed.
1198 static int nfs_create(struct inode
*dir
, struct dentry
*dentry
, int mode
,
1199 struct nameidata
*nd
)
1205 dfprintk(VFS
, "NFS: create(%s/%ld), %s\n",
1206 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1208 attr
.ia_mode
= mode
;
1209 attr
.ia_valid
= ATTR_MODE
;
1211 if ((nd
->flags
& LOOKUP_CREATE
) != 0)
1212 open_flags
= nd
->intent
.open
.flags
;
1215 error
= NFS_PROTO(dir
)->create(dir
, dentry
, &attr
, open_flags
, nd
);
1227 * See comments for nfs_proc_create regarding failed operations.
1230 nfs_mknod(struct inode
*dir
, struct dentry
*dentry
, int mode
, dev_t rdev
)
1235 dfprintk(VFS
, "NFS: mknod(%s/%ld), %s\n",
1236 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1238 if (!new_valid_dev(rdev
))
1241 attr
.ia_mode
= mode
;
1242 attr
.ia_valid
= ATTR_MODE
;
1245 status
= NFS_PROTO(dir
)->mknod(dir
, dentry
, &attr
, rdev
);
1257 * See comments for nfs_proc_create regarding failed operations.
1259 static int nfs_mkdir(struct inode
*dir
, struct dentry
*dentry
, int mode
)
1264 dfprintk(VFS
, "NFS: mkdir(%s/%ld), %s\n",
1265 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1267 attr
.ia_valid
= ATTR_MODE
;
1268 attr
.ia_mode
= mode
| S_IFDIR
;
1271 error
= NFS_PROTO(dir
)->mkdir(dir
, dentry
, &attr
);
1282 static int nfs_rmdir(struct inode
*dir
, struct dentry
*dentry
)
1286 dfprintk(VFS
, "NFS: rmdir(%s/%ld), %s\n",
1287 dir
->i_sb
->s_id
, dir
->i_ino
, dentry
->d_name
.name
);
1290 error
= NFS_PROTO(dir
)->rmdir(dir
, &dentry
->d_name
);
1291 /* Ensure the VFS deletes this inode */
1292 if (error
== 0 && dentry
->d_inode
!= NULL
)
1293 clear_nlink(dentry
->d_inode
);
1299 static int nfs_sillyrename(struct inode
*dir
, struct dentry
*dentry
)
1301 static unsigned int sillycounter
;
1302 const int fileidsize
= sizeof(NFS_FILEID(dentry
->d_inode
))*2;
1303 const int countersize
= sizeof(sillycounter
)*2;
1304 const int slen
= sizeof(".nfs")+fileidsize
+countersize
-1;
1307 struct dentry
*sdentry
;
1310 dfprintk(VFS
, "NFS: silly-rename(%s/%s, ct=%d)\n",
1311 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
,
1312 atomic_read(&dentry
->d_count
));
1313 nfs_inc_stats(dir
, NFSIOS_SILLYRENAME
);
1316 * We don't allow a dentry to be silly-renamed twice.
1319 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
)
1322 sprintf(silly
, ".nfs%*.*Lx",
1323 fileidsize
, fileidsize
,
1324 (unsigned long long)NFS_FILEID(dentry
->d_inode
));
1326 /* Return delegation in anticipation of the rename */
1327 nfs_inode_return_delegation(dentry
->d_inode
);
1331 char *suffix
= silly
+ slen
- countersize
;
1335 sprintf(suffix
, "%*.*x", countersize
, countersize
, sillycounter
);
1337 dfprintk(VFS
, "NFS: trying to rename %s to %s\n",
1338 dentry
->d_name
.name
, silly
);
1340 sdentry
= lookup_one_len(silly
, dentry
->d_parent
, slen
);
1342 * N.B. Better to return EBUSY here ... it could be
1343 * dangerous to delete the file while it's in use.
1345 if (IS_ERR(sdentry
))
1347 } while(sdentry
->d_inode
!= NULL
); /* need negative lookup */
1349 qsilly
.name
= silly
;
1350 qsilly
.len
= strlen(silly
);
1351 if (dentry
->d_inode
) {
1352 error
= NFS_PROTO(dir
)->rename(dir
, &dentry
->d_name
,
1354 nfs_mark_for_revalidate(dentry
->d_inode
);
1356 error
= NFS_PROTO(dir
)->rename(dir
, &dentry
->d_name
,
1359 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1360 d_move(dentry
, sdentry
);
1361 error
= nfs_async_unlink(dir
, dentry
);
1362 /* If we return 0 we don't unlink */
1370 * Remove a file after making sure there are no pending writes,
1371 * and after checking that the file has only one user.
1373 * We invalidate the attribute cache and free the inode prior to the operation
1374 * to avoid possible races if the server reuses the inode.
1376 static int nfs_safe_remove(struct dentry
*dentry
)
1378 struct inode
*dir
= dentry
->d_parent
->d_inode
;
1379 struct inode
*inode
= dentry
->d_inode
;
1382 dfprintk(VFS
, "NFS: safe_remove(%s/%s)\n",
1383 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
1385 /* If the dentry was sillyrenamed, we simply call d_delete() */
1386 if (dentry
->d_flags
& DCACHE_NFSFS_RENAMED
) {
1391 if (inode
!= NULL
) {
1392 nfs_inode_return_delegation(inode
);
1393 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1394 /* The VFS may want to delete this inode */
1397 nfs_mark_for_revalidate(inode
);
1399 error
= NFS_PROTO(dir
)->remove(dir
, &dentry
->d_name
);
1404 /* We do silly rename. In case sillyrename() returns -EBUSY, the inode
1405 * belongs to an active ".nfs..." file and we return -EBUSY.
1407 * If sillyrename() returns 0, we do nothing, otherwise we unlink.
1409 static int nfs_unlink(struct inode
*dir
, struct dentry
*dentry
)
1412 int need_rehash
= 0;
1414 dfprintk(VFS
, "NFS: unlink(%s/%ld, %s)\n", dir
->i_sb
->s_id
,
1415 dir
->i_ino
, dentry
->d_name
.name
);
1418 spin_lock(&dcache_lock
);
1419 spin_lock(&dentry
->d_lock
);
1420 if (atomic_read(&dentry
->d_count
) > 1) {
1421 spin_unlock(&dentry
->d_lock
);
1422 spin_unlock(&dcache_lock
);
1423 /* Start asynchronous writeout of the inode */
1424 write_inode_now(dentry
->d_inode
, 0);
1425 error
= nfs_sillyrename(dir
, dentry
);
1429 if (!d_unhashed(dentry
)) {
1433 spin_unlock(&dentry
->d_lock
);
1434 spin_unlock(&dcache_lock
);
1435 error
= nfs_safe_remove(dentry
);
1437 nfs_set_verifier(dentry
, nfs_save_change_attribute(dir
));
1438 } else if (need_rehash
)
1445 * To create a symbolic link, most file systems instantiate a new inode,
1446 * add a page to it containing the path, then write it out to the disk
1447 * using prepare_write/commit_write.
1449 * Unfortunately the NFS client can't create the in-core inode first
1450 * because it needs a file handle to create an in-core inode (see
1451 * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the
1452 * symlink request has completed on the server.
1454 * So instead we allocate a raw page, copy the symname into it, then do
1455 * the SYMLINK request with the page as the buffer. If it succeeds, we
1456 * now have a new file handle and can instantiate an in-core NFS inode
1457 * and move the raw page into its mapping.
1459 static int nfs_symlink(struct inode
*dir
, struct dentry
*dentry
, const char *symname
)
1461 struct pagevec lru_pvec
;
1465 unsigned int pathlen
= strlen(symname
);
1468 dfprintk(VFS
, "NFS: symlink(%s/%ld, %s, %s)\n", dir
->i_sb
->s_id
,
1469 dir
->i_ino
, dentry
->d_name
.name
, symname
);
1471 if (pathlen
> PAGE_SIZE
)
1472 return -ENAMETOOLONG
;
1474 attr
.ia_mode
= S_IFLNK
| S_IRWXUGO
;
1475 attr
.ia_valid
= ATTR_MODE
;
1479 page
= alloc_page(GFP_HIGHUSER
);
1485 kaddr
= kmap_atomic(page
, KM_USER0
);
1486 memcpy(kaddr
, symname
, pathlen
);
1487 if (pathlen
< PAGE_SIZE
)
1488 memset(kaddr
+ pathlen
, 0, PAGE_SIZE
- pathlen
);
1489 kunmap_atomic(kaddr
, KM_USER0
);
1491 error
= NFS_PROTO(dir
)->symlink(dir
, dentry
, page
, pathlen
, &attr
);
1493 dfprintk(VFS
, "NFS: symlink(%s/%ld, %s, %s) error %d\n",
1494 dir
->i_sb
->s_id
, dir
->i_ino
,
1495 dentry
->d_name
.name
, symname
, error
);
1503 * No big deal if we can't add this page to the page cache here.
1504 * READLINK will get the missing page from the server if needed.
1506 pagevec_init(&lru_pvec
, 0);
1507 if (!add_to_page_cache(page
, dentry
->d_inode
->i_mapping
, 0,
1509 pagevec_add(&lru_pvec
, page
);
1510 pagevec_lru_add(&lru_pvec
);
1511 SetPageUptodate(page
);
1521 nfs_link(struct dentry
*old_dentry
, struct inode
*dir
, struct dentry
*dentry
)
1523 struct inode
*inode
= old_dentry
->d_inode
;
1526 dfprintk(VFS
, "NFS: link(%s/%s -> %s/%s)\n",
1527 old_dentry
->d_parent
->d_name
.name
, old_dentry
->d_name
.name
,
1528 dentry
->d_parent
->d_name
.name
, dentry
->d_name
.name
);
1531 error
= NFS_PROTO(dir
)->link(inode
, dir
, &dentry
->d_name
);
1533 atomic_inc(&inode
->i_count
);
1534 d_instantiate(dentry
, inode
);
1542 * FIXME: Some nfsds, like the Linux user space nfsd, may generate a
1543 * different file handle for the same inode after a rename (e.g. when
1544 * moving to a different directory). A fail-safe method to do so would
1545 * be to look up old_dir/old_name, create a link to new_dir/new_name and
1546 * rename the old file using the sillyrename stuff. This way, the original
1547 * file in old_dir will go away when the last process iput()s the inode.
1551 * It actually works quite well. One needs to have the possibility for
1552 * at least one ".nfs..." file in each directory the file ever gets
1553 * moved or linked to which happens automagically with the new
1554 * implementation that only depends on the dcache stuff instead of
1555 * using the inode layer
1557 * Unfortunately, things are a little more complicated than indicated
1558 * above. For a cross-directory move, we want to make sure we can get
1559 * rid of the old inode after the operation. This means there must be
1560 * no pending writes (if it's a file), and the use count must be 1.
1561 * If these conditions are met, we can drop the dentries before doing
1564 static int nfs_rename(struct inode
*old_dir
, struct dentry
*old_dentry
,
1565 struct inode
*new_dir
, struct dentry
*new_dentry
)
1567 struct inode
*old_inode
= old_dentry
->d_inode
;
1568 struct inode
*new_inode
= new_dentry
->d_inode
;
1569 struct dentry
*dentry
= NULL
, *rehash
= NULL
;
1573 * To prevent any new references to the target during the rename,
1574 * we unhash the dentry and free the inode in advance.
1577 if (!d_unhashed(new_dentry
)) {
1579 rehash
= new_dentry
;
1582 dfprintk(VFS
, "NFS: rename(%s/%s -> %s/%s, ct=%d)\n",
1583 old_dentry
->d_parent
->d_name
.name
, old_dentry
->d_name
.name
,
1584 new_dentry
->d_parent
->d_name
.name
, new_dentry
->d_name
.name
,
1585 atomic_read(&new_dentry
->d_count
));
1588 * First check whether the target is busy ... we can't
1589 * safely do _any_ rename if the target is in use.
1591 * For files, make a copy of the dentry and then do a
1592 * silly-rename. If the silly-rename succeeds, the
1593 * copied dentry is hashed and becomes the new target.
1597 if (S_ISDIR(new_inode
->i_mode
)) {
1599 if (!S_ISDIR(old_inode
->i_mode
))
1601 } else if (atomic_read(&new_dentry
->d_count
) > 2) {
1603 /* copy the target dentry's name */
1604 dentry
= d_alloc(new_dentry
->d_parent
,
1605 &new_dentry
->d_name
);
1609 /* silly-rename the existing target ... */
1610 err
= nfs_sillyrename(new_dir
, new_dentry
);
1612 new_dentry
= rehash
= dentry
;
1614 /* instantiate the replacement target */
1615 d_instantiate(new_dentry
, NULL
);
1616 } else if (atomic_read(&new_dentry
->d_count
) > 1)
1617 /* dentry still busy? */
1620 drop_nlink(new_inode
);
1624 * ... prune child dentries and writebacks if needed.
1626 if (atomic_read(&old_dentry
->d_count
) > 1) {
1627 if (S_ISREG(old_inode
->i_mode
))
1628 nfs_wb_all(old_inode
);
1629 shrink_dcache_parent(old_dentry
);
1631 nfs_inode_return_delegation(old_inode
);
1633 if (new_inode
!= NULL
) {
1634 nfs_inode_return_delegation(new_inode
);
1635 d_delete(new_dentry
);
1638 error
= NFS_PROTO(old_dir
)->rename(old_dir
, &old_dentry
->d_name
,
1639 new_dir
, &new_dentry
->d_name
);
1640 nfs_mark_for_revalidate(old_inode
);
1645 d_move(old_dentry
, new_dentry
);
1646 nfs_set_verifier(new_dentry
,
1647 nfs_save_change_attribute(new_dir
));
1650 /* new dentry created? */
1657 static DEFINE_SPINLOCK(nfs_access_lru_lock
);
1658 static LIST_HEAD(nfs_access_lru_list
);
1659 static atomic_long_t nfs_access_nr_entries
;
1661 static void nfs_access_free_entry(struct nfs_access_entry
*entry
)
1663 put_rpccred(entry
->cred
);
1665 smp_mb__before_atomic_dec();
1666 atomic_long_dec(&nfs_access_nr_entries
);
1667 smp_mb__after_atomic_dec();
1670 int nfs_access_cache_shrinker(int nr_to_scan
, gfp_t gfp_mask
)
1673 struct nfs_inode
*nfsi
;
1674 struct nfs_access_entry
*cache
;
1677 spin_lock(&nfs_access_lru_lock
);
1678 list_for_each_entry(nfsi
, &nfs_access_lru_list
, access_cache_inode_lru
) {
1679 struct inode
*inode
;
1681 if (nr_to_scan
-- == 0)
1683 inode
= igrab(&nfsi
->vfs_inode
);
1686 spin_lock(&inode
->i_lock
);
1687 if (list_empty(&nfsi
->access_cache_entry_lru
))
1688 goto remove_lru_entry
;
1689 cache
= list_entry(nfsi
->access_cache_entry_lru
.next
,
1690 struct nfs_access_entry
, lru
);
1691 list_move(&cache
->lru
, &head
);
1692 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
1693 if (!list_empty(&nfsi
->access_cache_entry_lru
))
1694 list_move_tail(&nfsi
->access_cache_inode_lru
,
1695 &nfs_access_lru_list
);
1698 list_del_init(&nfsi
->access_cache_inode_lru
);
1699 clear_bit(NFS_INO_ACL_LRU_SET
, &nfsi
->flags
);
1701 spin_unlock(&inode
->i_lock
);
1702 spin_unlock(&nfs_access_lru_lock
);
1706 spin_unlock(&nfs_access_lru_lock
);
1707 while (!list_empty(&head
)) {
1708 cache
= list_entry(head
.next
, struct nfs_access_entry
, lru
);
1709 list_del(&cache
->lru
);
1710 nfs_access_free_entry(cache
);
1712 return (atomic_long_read(&nfs_access_nr_entries
) / 100) * sysctl_vfs_cache_pressure
;
1715 static void __nfs_access_zap_cache(struct inode
*inode
)
1717 struct nfs_inode
*nfsi
= NFS_I(inode
);
1718 struct rb_root
*root_node
= &nfsi
->access_cache
;
1719 struct rb_node
*n
, *dispose
= NULL
;
1720 struct nfs_access_entry
*entry
;
1722 /* Unhook entries from the cache */
1723 while ((n
= rb_first(root_node
)) != NULL
) {
1724 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
1725 rb_erase(n
, root_node
);
1726 list_del(&entry
->lru
);
1727 n
->rb_left
= dispose
;
1730 nfsi
->cache_validity
&= ~NFS_INO_INVALID_ACCESS
;
1731 spin_unlock(&inode
->i_lock
);
1733 /* Now kill them all! */
1734 while (dispose
!= NULL
) {
1736 dispose
= n
->rb_left
;
1737 nfs_access_free_entry(rb_entry(n
, struct nfs_access_entry
, rb_node
));
1741 void nfs_access_zap_cache(struct inode
*inode
)
1743 /* Remove from global LRU init */
1744 if (test_and_clear_bit(NFS_INO_ACL_LRU_SET
, &NFS_FLAGS(inode
))) {
1745 spin_lock(&nfs_access_lru_lock
);
1746 list_del_init(&NFS_I(inode
)->access_cache_inode_lru
);
1747 spin_unlock(&nfs_access_lru_lock
);
1750 spin_lock(&inode
->i_lock
);
1751 /* This will release the spinlock */
1752 __nfs_access_zap_cache(inode
);
1755 static struct nfs_access_entry
*nfs_access_search_rbtree(struct inode
*inode
, struct rpc_cred
*cred
)
1757 struct rb_node
*n
= NFS_I(inode
)->access_cache
.rb_node
;
1758 struct nfs_access_entry
*entry
;
1761 entry
= rb_entry(n
, struct nfs_access_entry
, rb_node
);
1763 if (cred
< entry
->cred
)
1765 else if (cred
> entry
->cred
)
1773 static int nfs_access_get_cached(struct inode
*inode
, struct rpc_cred
*cred
, struct nfs_access_entry
*res
)
1775 struct nfs_inode
*nfsi
= NFS_I(inode
);
1776 struct nfs_access_entry
*cache
;
1779 spin_lock(&inode
->i_lock
);
1780 if (nfsi
->cache_validity
& NFS_INO_INVALID_ACCESS
)
1782 cache
= nfs_access_search_rbtree(inode
, cred
);
1785 if (!time_in_range(jiffies
, cache
->jiffies
, cache
->jiffies
+ NFS_ATTRTIMEO(inode
)))
1787 res
->jiffies
= cache
->jiffies
;
1788 res
->cred
= cache
->cred
;
1789 res
->mask
= cache
->mask
;
1790 list_move_tail(&cache
->lru
, &nfsi
->access_cache_entry_lru
);
1793 spin_unlock(&inode
->i_lock
);
1796 rb_erase(&cache
->rb_node
, &nfsi
->access_cache
);
1797 list_del(&cache
->lru
);
1798 spin_unlock(&inode
->i_lock
);
1799 nfs_access_free_entry(cache
);
1802 /* This will release the spinlock */
1803 __nfs_access_zap_cache(inode
);
1807 static void nfs_access_add_rbtree(struct inode
*inode
, struct nfs_access_entry
*set
)
1809 struct nfs_inode
*nfsi
= NFS_I(inode
);
1810 struct rb_root
*root_node
= &nfsi
->access_cache
;
1811 struct rb_node
**p
= &root_node
->rb_node
;
1812 struct rb_node
*parent
= NULL
;
1813 struct nfs_access_entry
*entry
;
1815 spin_lock(&inode
->i_lock
);
1816 while (*p
!= NULL
) {
1818 entry
= rb_entry(parent
, struct nfs_access_entry
, rb_node
);
1820 if (set
->cred
< entry
->cred
)
1821 p
= &parent
->rb_left
;
1822 else if (set
->cred
> entry
->cred
)
1823 p
= &parent
->rb_right
;
1827 rb_link_node(&set
->rb_node
, parent
, p
);
1828 rb_insert_color(&set
->rb_node
, root_node
);
1829 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
1830 spin_unlock(&inode
->i_lock
);
1833 rb_replace_node(parent
, &set
->rb_node
, root_node
);
1834 list_add_tail(&set
->lru
, &nfsi
->access_cache_entry_lru
);
1835 list_del(&entry
->lru
);
1836 spin_unlock(&inode
->i_lock
);
1837 nfs_access_free_entry(entry
);
1840 static void nfs_access_add_cache(struct inode
*inode
, struct nfs_access_entry
*set
)
1842 struct nfs_access_entry
*cache
= kmalloc(sizeof(*cache
), GFP_KERNEL
);
1845 RB_CLEAR_NODE(&cache
->rb_node
);
1846 cache
->jiffies
= set
->jiffies
;
1847 cache
->cred
= get_rpccred(set
->cred
);
1848 cache
->mask
= set
->mask
;
1850 nfs_access_add_rbtree(inode
, cache
);
1852 /* Update accounting */
1853 smp_mb__before_atomic_inc();
1854 atomic_long_inc(&nfs_access_nr_entries
);
1855 smp_mb__after_atomic_inc();
1857 /* Add inode to global LRU list */
1858 if (!test_and_set_bit(NFS_INO_ACL_LRU_SET
, &NFS_FLAGS(inode
))) {
1859 spin_lock(&nfs_access_lru_lock
);
1860 list_add_tail(&NFS_I(inode
)->access_cache_inode_lru
, &nfs_access_lru_list
);
1861 spin_unlock(&nfs_access_lru_lock
);
1865 static int nfs_do_access(struct inode
*inode
, struct rpc_cred
*cred
, int mask
)
1867 struct nfs_access_entry cache
;
1870 status
= nfs_access_get_cached(inode
, cred
, &cache
);
1874 /* Be clever: ask server to check for all possible rights */
1875 cache
.mask
= MAY_EXEC
| MAY_WRITE
| MAY_READ
;
1877 cache
.jiffies
= jiffies
;
1878 status
= NFS_PROTO(inode
)->access(inode
, &cache
);
1881 nfs_access_add_cache(inode
, &cache
);
1883 if ((cache
.mask
& mask
) == mask
)
1888 static int nfs_open_permission_mask(int openflags
)
1892 if (openflags
& FMODE_READ
)
1894 if (openflags
& FMODE_WRITE
)
1896 if (openflags
& FMODE_EXEC
)
1901 int nfs_may_open(struct inode
*inode
, struct rpc_cred
*cred
, int openflags
)
1903 return nfs_do_access(inode
, cred
, nfs_open_permission_mask(openflags
));
1906 int nfs_permission(struct inode
*inode
, int mask
, struct nameidata
*nd
)
1908 struct rpc_cred
*cred
;
1911 nfs_inc_stats(inode
, NFSIOS_VFSACCESS
);
1915 /* Is this sys_access() ? */
1916 if (nd
!= NULL
&& (nd
->flags
& LOOKUP_ACCESS
))
1919 switch (inode
->i_mode
& S_IFMT
) {
1923 /* NFSv4 has atomic_open... */
1924 if (nfs_server_capable(inode
, NFS_CAP_ATOMIC_OPEN
)
1926 && (nd
->flags
& LOOKUP_OPEN
))
1931 * Optimize away all write operations, since the server
1932 * will check permissions when we perform the op.
1934 if ((mask
& MAY_WRITE
) && !(mask
& MAY_READ
))
1941 if (!NFS_PROTO(inode
)->access
)
1944 cred
= rpcauth_lookupcred(NFS_CLIENT(inode
)->cl_auth
, 0);
1945 if (!IS_ERR(cred
)) {
1946 res
= nfs_do_access(inode
, cred
, mask
);
1949 res
= PTR_ERR(cred
);
1952 dfprintk(VFS
, "NFS: permission(%s/%ld), mask=0x%x, res=%d\n",
1953 inode
->i_sb
->s_id
, inode
->i_ino
, mask
, res
);
1956 res
= nfs_revalidate_inode(NFS_SERVER(inode
), inode
);
1958 res
= generic_permission(inode
, mask
, NULL
);
1965 * version-control: t
1966 * kept-new-versions: 5