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);
220 int dir_decode(nfs_readdir_descriptor_t *desc)
222 __be32 *p = desc->ptr;
223 p = desc->decode(p, desc->entry, desc->plus);
227 if (desc->timestamp_valid)
228 desc->entry->fattr->time_start = desc->timestamp;
230 desc->entry->fattr->valid &= ~NFS_ATTR_FATTR;
235 void dir_page_release(nfs_readdir_descriptor_t *desc)
238 page_cache_release(desc->page);
244 * Given a pointer to a buffer that has already been filled by a call
245 * to readdir, find the next entry with cookie '*desc->dir_cookie'.
247 * If the end of the buffer has been reached, return -EAGAIN, if not,
248 * return the offset within the buffer of the next entry to be
252 int find_dirent(nfs_readdir_descriptor_t *desc)
254 struct nfs_entry *entry = desc->entry;
258 while((status = dir_decode(desc)) == 0) {
259 dfprintk(DIRCACHE, "NFS: %s: examining cookie %Lu\n",
260 __FUNCTION__, (unsigned long long)entry->cookie);
261 if (entry->prev_cookie == *desc->dir_cookie)
263 if (loop_count++ > 200) {
272 * Given a pointer to a buffer that has already been filled by a call
273 * to readdir, find the entry at offset 'desc->file->f_pos'.
275 * If the end of the buffer has been reached, return -EAGAIN, if not,
276 * return the offset within the buffer of the next entry to be
280 int find_dirent_index(nfs_readdir_descriptor_t *desc)
282 struct nfs_entry *entry = desc->entry;
287 status = dir_decode(desc);
291 dfprintk(DIRCACHE, "NFS: found cookie %Lu at index %Ld\n",
292 (unsigned long long)entry->cookie, desc->current_index);
294 if (desc->file->f_pos == desc->current_index) {
295 *desc->dir_cookie = entry->cookie;
298 desc->current_index++;
299 if (loop_count++ > 200) {
308 * Find the given page, and call find_dirent() or find_dirent_index in
309 * order to try to return the next entry.
312 int find_dirent_page(nfs_readdir_descriptor_t *desc)
314 struct inode *inode = desc->file->f_path.dentry->d_inode;
318 dfprintk(DIRCACHE, "NFS: %s: searching page %ld for target %Lu\n",
319 __FUNCTION__, desc->page_index,
320 (long long) *desc->dir_cookie);
322 /* If we find the page in the page_cache, we cannot be sure
323 * how fresh the data is, so we will ignore readdir_plus attributes.
325 desc->timestamp_valid = 0;
326 page = read_cache_page(inode->i_mapping, desc->page_index,
327 (filler_t *)nfs_readdir_filler, desc);
329 status = PTR_ERR(page);
333 /* NOTE: Someone else may have changed the READDIRPLUS flag */
335 desc->ptr = kmap(page); /* matching kunmap in nfs_do_filldir */
336 if (*desc->dir_cookie != 0)
337 status = find_dirent(desc);
339 status = find_dirent_index(desc);
341 dir_page_release(desc);
343 dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __FUNCTION__, status);
348 * Recurse through the page cache pages, and return a
349 * filled nfs_entry structure of the next directory entry if possible.
351 * The target for the search is '*desc->dir_cookie' if non-0,
352 * 'desc->file->f_pos' otherwise
355 int readdir_search_pagecache(nfs_readdir_descriptor_t *desc)
360 /* Always search-by-index from the beginning of the cache */
361 if (*desc->dir_cookie == 0) {
362 dfprintk(DIRCACHE, "NFS: readdir_search_pagecache() searching for offset %Ld\n",
363 (long long)desc->file->f_pos);
364 desc->page_index = 0;
365 desc->entry->cookie = desc->entry->prev_cookie = 0;
366 desc->entry->eof = 0;
367 desc->current_index = 0;
369 dfprintk(DIRCACHE, "NFS: readdir_search_pagecache() searching for cookie %Lu\n",
370 (unsigned long long)*desc->dir_cookie);
373 res = find_dirent_page(desc);
376 /* Align to beginning of next page */
378 if (loop_count++ > 200) {
384 dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __FUNCTION__, res);
388 static inline unsigned int dt_type(struct inode *inode)
390 return (inode->i_mode >> 12) & 15;
393 static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc);
396 * Once we've found the start of the dirent within a page: fill 'er up...
399 int nfs_do_filldir(nfs_readdir_descriptor_t *desc, void *dirent,
402 struct file *file = desc->file;
403 struct nfs_entry *entry = desc->entry;
404 struct dentry *dentry = NULL;
409 dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling starting @ cookie %Lu\n",
410 (unsigned long long)entry->cookie);
413 unsigned d_type = DT_UNKNOWN;
414 /* Note: entry->prev_cookie contains the cookie for
415 * retrieving the current dirent on the server */
418 /* Get a dentry if we have one */
421 dentry = nfs_readdir_lookup(desc);
423 /* Use readdirplus info */
424 if (dentry != NULL && dentry->d_inode != NULL) {
425 d_type = dt_type(dentry->d_inode);
426 fileid = NFS_FILEID(dentry->d_inode);
429 res = filldir(dirent, entry->name, entry->len,
430 file->f_pos, fileid, d_type);
434 *desc->dir_cookie = entry->cookie;
435 if (dir_decode(desc) != 0) {
439 if (loop_count++ > 200) {
444 dir_page_release(desc);
447 dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n",
448 (unsigned long long)*desc->dir_cookie, res);
453 * If we cannot find a cookie in our cache, we suspect that this is
454 * because it points to a deleted file, so we ask the server to return
455 * whatever it thinks is the next entry. We then feed this to filldir.
456 * If all goes well, we should then be able to find our way round the
457 * cache on the next call to readdir_search_pagecache();
459 * NOTE: we cannot add the anonymous page to the pagecache because
460 * the data it contains might not be page aligned. Besides,
461 * we should already have a complete representation of the
462 * directory in the page cache by the time we get here.
465 int uncached_readdir(nfs_readdir_descriptor_t *desc, void *dirent,
468 struct file *file = desc->file;
469 struct inode *inode = file->f_path.dentry->d_inode;
470 struct rpc_cred *cred = nfs_file_cred(file);
471 struct page *page = NULL;
473 unsigned long timestamp;
475 dfprintk(DIRCACHE, "NFS: uncached_readdir() searching for cookie %Lu\n",
476 (unsigned long long)*desc->dir_cookie);
478 page = alloc_page(GFP_HIGHUSER);
484 desc->error = NFS_PROTO(inode)->readdir(file->f_path.dentry, cred, *desc->dir_cookie,
486 NFS_SERVER(inode)->dtsize,
489 desc->ptr = kmap(page); /* matching kunmap in nfs_do_filldir */
490 if (desc->error >= 0) {
491 desc->timestamp = timestamp;
492 desc->timestamp_valid = 1;
493 if ((status = dir_decode(desc)) == 0)
494 desc->entry->prev_cookie = *desc->dir_cookie;
500 status = nfs_do_filldir(desc, dirent, filldir);
502 /* Reset read descriptor so it searches the page cache from
503 * the start upon the next call to readdir_search_pagecache() */
504 desc->page_index = 0;
505 desc->entry->cookie = desc->entry->prev_cookie = 0;
506 desc->entry->eof = 0;
508 dfprintk(DIRCACHE, "NFS: %s: returns %d\n",
509 __FUNCTION__, status);
512 dir_page_release(desc);
516 /* The file offset position represents the dirent entry number. A
517 last cookie cache takes care of the common case of reading the
520 static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
522 struct dentry *dentry = filp->f_path.dentry;
523 struct inode *inode = dentry->d_inode;
524 nfs_readdir_descriptor_t my_desc,
526 struct nfs_entry my_entry;
528 struct nfs_fattr fattr;
531 dfprintk(VFS, "NFS: readdir(%s/%s) starting at cookie %Lu\n",
532 dentry->d_parent->d_name.name, dentry->d_name.name,
533 (long long)filp->f_pos);
534 nfs_inc_stats(inode, NFSIOS_VFSGETDENTS);
538 res = nfs_revalidate_mapping_nolock(inode, filp->f_mapping);
545 * filp->f_pos points to the dirent entry number.
546 * *desc->dir_cookie has the cookie for the next entry. We have
547 * to either find the entry with the appropriate number or
548 * revalidate the cookie.
550 memset(desc, 0, sizeof(*desc));
553 desc->dir_cookie = &nfs_file_open_context(filp)->dir_cookie;
554 desc->decode = NFS_PROTO(inode)->decode_dirent;
555 desc->plus = NFS_USE_READDIRPLUS(inode);
557 my_entry.cookie = my_entry.prev_cookie = 0;
560 my_entry.fattr = &fattr;
561 nfs_fattr_init(&fattr);
562 desc->entry = &my_entry;
564 while(!desc->entry->eof) {
565 res = readdir_search_pagecache(desc);
567 if (res == -EBADCOOKIE) {
568 /* This means either end of directory */
569 if (*desc->dir_cookie && desc->entry->cookie != *desc->dir_cookie) {
570 /* Or that the server has 'lost' a cookie */
571 res = uncached_readdir(desc, dirent, filldir);
578 if (res == -ETOOSMALL && desc->plus) {
579 clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_FLAGS(inode));
580 nfs_zap_caches(inode);
582 desc->entry->eof = 0;
588 res = nfs_do_filldir(desc, dirent, filldir);
597 dfprintk(VFS, "NFS: readdir(%s/%s) returns %ld\n",
598 dentry->d_parent->d_name.name, dentry->d_name.name,
603 static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int origin)
605 mutex_lock(&filp->f_path.dentry->d_inode->i_mutex);
608 offset += filp->f_pos;
616 if (offset != filp->f_pos) {
617 filp->f_pos = offset;
618 nfs_file_open_context(filp)->dir_cookie = 0;
621 mutex_unlock(&filp->f_path.dentry->d_inode->i_mutex);
626 * All directory operations under NFS are synchronous, so fsync()
627 * is a dummy operation.
629 static int nfs_fsync_dir(struct file *filp, struct dentry *dentry, int datasync)
631 dfprintk(VFS, "NFS: fsync_dir(%s/%s) datasync %d\n",
632 dentry->d_parent->d_name.name, dentry->d_name.name,
639 * A check for whether or not the parent directory has changed.
640 * In the case it has, we assume that the dentries are untrustworthy
641 * and may need to be looked up again.
643 static int nfs_check_verifier(struct inode *dir, struct dentry *dentry)
647 if (!nfs_verify_change_attribute(dir, dentry->d_time))
649 /* Revalidate nfsi->cache_change_attribute before we declare a match */
650 if (nfs_revalidate_inode(NFS_SERVER(dir), dir) < 0)
652 if (!nfs_verify_change_attribute(dir, dentry->d_time))
658 * Return the intent data that applies to this particular path component
660 * Note that the current set of intents only apply to the very last
661 * component of the path.
662 * We check for this using LOOKUP_CONTINUE and LOOKUP_PARENT.
664 static inline unsigned int nfs_lookup_check_intent(struct nameidata *nd, unsigned int mask)
666 if (nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT))
668 return nd->flags & mask;
672 * Use intent information to check whether or not we're going to do
673 * an O_EXCL create using this path component.
675 static int nfs_is_exclusive_create(struct inode *dir, struct nameidata *nd)
677 if (NFS_PROTO(dir)->version == 2)
679 if (nd == NULL || nfs_lookup_check_intent(nd, LOOKUP_CREATE) == 0)
681 return (nd->intent.open.flags & O_EXCL) != 0;
685 * Inode and filehandle revalidation for lookups.
687 * We force revalidation in the cases where the VFS sets LOOKUP_REVAL,
688 * or if the intent information indicates that we're about to open this
689 * particular file and the "nocto" mount flag is not set.
693 int nfs_lookup_verify_inode(struct inode *inode, struct nameidata *nd)
695 struct nfs_server *server = NFS_SERVER(inode);
698 /* VFS wants an on-the-wire revalidation */
699 if (nd->flags & LOOKUP_REVAL)
701 /* This is an open(2) */
702 if (nfs_lookup_check_intent(nd, LOOKUP_OPEN) != 0 &&
703 !(server->flags & NFS_MOUNT_NOCTO) &&
704 (S_ISREG(inode->i_mode) ||
705 S_ISDIR(inode->i_mode)))
708 return nfs_revalidate_inode(server, inode);
710 return __nfs_revalidate_inode(server, inode);
714 * We judge how long we want to trust negative
715 * dentries by looking at the parent inode mtime.
717 * If parent mtime has changed, we revalidate, else we wait for a
718 * period corresponding to the parent's attribute cache timeout value.
721 int nfs_neg_need_reval(struct inode *dir, struct dentry *dentry,
722 struct nameidata *nd)
724 /* Don't revalidate a negative dentry if we're creating a new file */
725 if (nd != NULL && nfs_lookup_check_intent(nd, LOOKUP_CREATE) != 0)
727 return !nfs_check_verifier(dir, dentry);
731 * This is called every time the dcache has a lookup hit,
732 * and we should check whether we can really trust that
735 * NOTE! The hit can be a negative hit too, don't assume
738 * If the parent directory is seen to have changed, we throw out the
739 * cached dentry and do a new lookup.
741 static int nfs_lookup_revalidate(struct dentry * dentry, struct nameidata *nd)
745 struct dentry *parent;
747 struct nfs_fh fhandle;
748 struct nfs_fattr fattr;
750 parent = dget_parent(dentry);
752 dir = parent->d_inode;
753 nfs_inc_stats(dir, NFSIOS_DENTRYREVALIDATE);
754 inode = dentry->d_inode;
757 if (nfs_neg_need_reval(dir, dentry, nd))
762 if (is_bad_inode(inode)) {
763 dfprintk(LOOKUPCACHE, "%s: %s/%s has dud inode\n",
764 __FUNCTION__, dentry->d_parent->d_name.name,
765 dentry->d_name.name);
769 /* Force a full look up iff the parent directory has changed */
770 if (!nfs_is_exclusive_create(dir, nd) && nfs_check_verifier(dir, dentry)) {
771 if (nfs_lookup_verify_inode(inode, nd))
776 if (NFS_STALE(inode))
779 error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, &fhandle, &fattr);
782 if (nfs_compare_fh(NFS_FH(inode), &fhandle))
784 if ((error = nfs_refresh_inode(inode, &fattr)) != 0)
787 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
791 dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is valid\n",
792 __FUNCTION__, dentry->d_parent->d_name.name,
793 dentry->d_name.name);
798 nfs_mark_for_revalidate(dir);
799 if (inode && S_ISDIR(inode->i_mode)) {
800 /* Purge readdir caches. */
801 nfs_zap_caches(inode);
802 /* If we have submounts, don't unhash ! */
803 if (have_submounts(dentry))
805 shrink_dcache_parent(dentry);
810 dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is invalid\n",
811 __FUNCTION__, dentry->d_parent->d_name.name,
812 dentry->d_name.name);
817 * This is called from dput() when d_count is going to 0.
819 static int nfs_dentry_delete(struct dentry *dentry)
821 dfprintk(VFS, "NFS: dentry_delete(%s/%s, %x)\n",
822 dentry->d_parent->d_name.name, dentry->d_name.name,
825 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
826 /* Unhash it, so that ->d_iput() would be called */
829 if (!(dentry->d_sb->s_flags & MS_ACTIVE)) {
830 /* Unhash it, so that ancestors of killed async unlink
831 * files will be cleaned up during umount */
839 * Called when the dentry loses inode.
840 * We use it to clean up silly-renamed files.
842 static void nfs_dentry_iput(struct dentry *dentry, struct inode *inode)
844 nfs_inode_return_delegation(inode);
845 if (S_ISDIR(inode->i_mode))
846 /* drop any readdir cache as it could easily be old */
847 NFS_I(inode)->cache_validity |= NFS_INO_INVALID_DATA;
849 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
852 nfs_complete_unlink(dentry, inode);
858 struct dentry_operations nfs_dentry_operations = {
859 .d_revalidate = nfs_lookup_revalidate,
860 .d_delete = nfs_dentry_delete,
861 .d_iput = nfs_dentry_iput,
864 static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
867 struct inode *inode = NULL;
869 struct nfs_fh fhandle;
870 struct nfs_fattr fattr;
872 dfprintk(VFS, "NFS: lookup(%s/%s)\n",
873 dentry->d_parent->d_name.name, dentry->d_name.name);
874 nfs_inc_stats(dir, NFSIOS_VFSLOOKUP);
876 res = ERR_PTR(-ENAMETOOLONG);
877 if (dentry->d_name.len > NFS_SERVER(dir)->namelen)
880 res = ERR_PTR(-ENOMEM);
881 dentry->d_op = NFS_PROTO(dir)->dentry_ops;
886 * If we're doing an exclusive create, optimize away the lookup
887 * but don't hash the dentry.
889 if (nfs_is_exclusive_create(dir, nd)) {
890 d_instantiate(dentry, NULL);
895 error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, &fhandle, &fattr);
896 if (error == -ENOENT)
899 res = ERR_PTR(error);
902 inode = nfs_fhget(dentry->d_sb, &fhandle, &fattr);
903 res = (struct dentry *)inode;
908 res = d_materialise_unique(dentry, inode);
914 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
922 static int nfs_open_revalidate(struct dentry *, struct nameidata *);
924 struct dentry_operations nfs4_dentry_operations = {
925 .d_revalidate = nfs_open_revalidate,
926 .d_delete = nfs_dentry_delete,
927 .d_iput = nfs_dentry_iput,
931 * Use intent information to determine whether we need to substitute
932 * the NFSv4-style stateful OPEN for the LOOKUP call
934 static int is_atomic_open(struct inode *dir, struct nameidata *nd)
936 if (nd == NULL || nfs_lookup_check_intent(nd, LOOKUP_OPEN) == 0)
938 /* NFS does not (yet) have a stateful open for directories */
939 if (nd->flags & LOOKUP_DIRECTORY)
941 /* Are we trying to write to a read only partition? */
942 if (IS_RDONLY(dir) && (nd->intent.open.flags & (O_CREAT|O_TRUNC|FMODE_WRITE)))
947 static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
949 struct dentry *res = NULL;
952 dfprintk(VFS, "NFS: atomic_lookup(%s/%ld), %s\n",
953 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
955 /* Check that we are indeed trying to open this file */
956 if (!is_atomic_open(dir, nd))
959 if (dentry->d_name.len > NFS_SERVER(dir)->namelen) {
960 res = ERR_PTR(-ENAMETOOLONG);
963 dentry->d_op = NFS_PROTO(dir)->dentry_ops;
965 /* Let vfs_create() deal with O_EXCL. Instantiate, but don't hash
967 if (nd->intent.open.flags & O_EXCL) {
968 d_instantiate(dentry, NULL);
972 /* Open the file on the server */
974 res = nfs4_atomic_open(dir, dentry, nd);
977 error = PTR_ERR(res);
979 /* Make a negative dentry */
983 /* This turned out not to be a regular file */
988 if (!(nd->intent.open.flags & O_NOFOLLOW))
994 } else if (res != NULL)
999 return nfs_lookup(dir, dentry, nd);
1002 static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
1004 struct dentry *parent = NULL;
1005 struct inode *inode = dentry->d_inode;
1007 int openflags, ret = 0;
1009 parent = dget_parent(dentry);
1010 dir = parent->d_inode;
1011 if (!is_atomic_open(dir, nd))
1013 /* We can't create new files in nfs_open_revalidate(), so we
1014 * optimize away revalidation of negative dentries.
1016 if (inode == NULL) {
1017 if (!nfs_neg_need_reval(dir, dentry, nd))
1022 /* NFS only supports OPEN on regular files */
1023 if (!S_ISREG(inode->i_mode))
1025 openflags = nd->intent.open.flags;
1026 /* We cannot do exclusive creation on a positive dentry */
1027 if ((openflags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL))
1029 /* We can't create new files, or truncate existing ones here */
1030 openflags &= ~(O_CREAT|O_TRUNC);
1033 * Note: we're not holding inode->i_mutex and so may be racing with
1034 * operations that change the directory. We therefore save the
1035 * change attribute *before* we do the RPC call.
1038 ret = nfs4_open_revalidate(dir, dentry, openflags, nd);
1047 if (inode != NULL && nfs_have_delegation(inode, FMODE_READ))
1049 return nfs_lookup_revalidate(dentry, nd);
1051 #endif /* CONFIG_NFSV4 */
1053 static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc)
1055 struct dentry *parent = desc->file->f_path.dentry;
1056 struct inode *dir = parent->d_inode;
1057 struct nfs_entry *entry = desc->entry;
1058 struct dentry *dentry, *alias;
1059 struct qstr name = {
1060 .name = entry->name,
1063 struct inode *inode;
1064 unsigned long verf = nfs_save_change_attribute(dir);
1068 if (name.name[0] == '.' && name.name[1] == '.')
1069 return dget_parent(parent);
1072 if (name.name[0] == '.')
1073 return dget(parent);
1076 spin_lock(&dir->i_lock);
1077 if (NFS_I(dir)->cache_validity & NFS_INO_INVALID_DATA) {
1078 spin_unlock(&dir->i_lock);
1081 spin_unlock(&dir->i_lock);
1083 name.hash = full_name_hash(name.name, name.len);
1084 dentry = d_lookup(parent, &name);
1085 if (dentry != NULL) {
1086 /* Is this a positive dentry that matches the readdir info? */
1087 if (dentry->d_inode != NULL &&
1088 (NFS_FILEID(dentry->d_inode) == entry->ino ||
1089 d_mountpoint(dentry))) {
1090 if (!desc->plus || entry->fh->size == 0)
1092 if (nfs_compare_fh(NFS_FH(dentry->d_inode),
1096 /* No, so d_drop to allow one to be created */
1100 if (!desc->plus || !(entry->fattr->valid & NFS_ATTR_FATTR))
1102 if (name.len > NFS_SERVER(dir)->namelen)
1104 /* Note: caller is already holding the dir->i_mutex! */
1105 dentry = d_alloc(parent, &name);
1108 dentry->d_op = NFS_PROTO(dir)->dentry_ops;
1109 inode = nfs_fhget(dentry->d_sb, entry->fh, entry->fattr);
1110 if (IS_ERR(inode)) {
1115 alias = d_materialise_unique(dentry, inode);
1116 if (alias != NULL) {
1124 nfs_set_verifier(dentry, verf);
1129 * Code common to create, mkdir, and mknod.
1131 int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fhandle,
1132 struct nfs_fattr *fattr)
1134 struct dentry *parent = dget_parent(dentry);
1135 struct inode *dir = parent->d_inode;
1136 struct inode *inode;
1137 int error = -EACCES;
1141 /* We may have been initialized further down */
1142 if (dentry->d_inode)
1144 if (fhandle->size == 0) {
1145 error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, fhandle, fattr);
1149 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1150 if (!(fattr->valid & NFS_ATTR_FATTR)) {
1151 struct nfs_server *server = NFS_SB(dentry->d_sb);
1152 error = server->nfs_client->rpc_ops->getattr(server, fhandle, fattr);
1156 inode = nfs_fhget(dentry->d_sb, fhandle, fattr);
1157 error = PTR_ERR(inode);
1160 d_add(dentry, inode);
1165 nfs_mark_for_revalidate(dir);
1171 * Following a failed create operation, we drop the dentry rather
1172 * than retain a negative dentry. This avoids a problem in the event
1173 * that the operation succeeded on the server, but an error in the
1174 * reply path made it appear to have failed.
1176 static int nfs_create(struct inode *dir, struct dentry *dentry, int mode,
1177 struct nameidata *nd)
1183 dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
1184 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1186 attr.ia_mode = mode;
1187 attr.ia_valid = ATTR_MODE;
1189 if ((nd->flags & LOOKUP_CREATE) != 0)
1190 open_flags = nd->intent.open.flags;
1193 error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, nd);
1205 * See comments for nfs_proc_create regarding failed operations.
1208 nfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
1213 dfprintk(VFS, "NFS: mknod(%s/%ld), %s\n",
1214 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1216 if (!new_valid_dev(rdev))
1219 attr.ia_mode = mode;
1220 attr.ia_valid = ATTR_MODE;
1223 status = NFS_PROTO(dir)->mknod(dir, dentry, &attr, rdev);
1235 * See comments for nfs_proc_create regarding failed operations.
1237 static int nfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
1242 dfprintk(VFS, "NFS: mkdir(%s/%ld), %s\n",
1243 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1245 attr.ia_valid = ATTR_MODE;
1246 attr.ia_mode = mode | S_IFDIR;
1249 error = NFS_PROTO(dir)->mkdir(dir, dentry, &attr);
1260 static int nfs_rmdir(struct inode *dir, struct dentry *dentry)
1264 dfprintk(VFS, "NFS: rmdir(%s/%ld), %s\n",
1265 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1268 error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name);
1269 /* Ensure the VFS deletes this inode */
1270 if (error == 0 && dentry->d_inode != NULL)
1271 clear_nlink(dentry->d_inode);
1277 static int nfs_sillyrename(struct inode *dir, struct dentry *dentry)
1279 static unsigned int sillycounter;
1280 const int fileidsize = sizeof(NFS_FILEID(dentry->d_inode))*2;
1281 const int countersize = sizeof(sillycounter)*2;
1282 const int slen = sizeof(".nfs")+fileidsize+countersize-1;
1285 struct dentry *sdentry;
1288 dfprintk(VFS, "NFS: silly-rename(%s/%s, ct=%d)\n",
1289 dentry->d_parent->d_name.name, dentry->d_name.name,
1290 atomic_read(&dentry->d_count));
1291 nfs_inc_stats(dir, NFSIOS_SILLYRENAME);
1294 * We don't allow a dentry to be silly-renamed twice.
1297 if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
1300 sprintf(silly, ".nfs%*.*Lx",
1301 fileidsize, fileidsize,
1302 (unsigned long long)NFS_FILEID(dentry->d_inode));
1304 /* Return delegation in anticipation of the rename */
1305 nfs_inode_return_delegation(dentry->d_inode);
1309 char *suffix = silly + slen - countersize;
1313 sprintf(suffix, "%*.*x", countersize, countersize, sillycounter);
1315 dfprintk(VFS, "NFS: trying to rename %s to %s\n",
1316 dentry->d_name.name, silly);
1318 sdentry = lookup_one_len(silly, dentry->d_parent, slen);
1320 * N.B. Better to return EBUSY here ... it could be
1321 * dangerous to delete the file while it's in use.
1323 if (IS_ERR(sdentry))
1325 } while(sdentry->d_inode != NULL); /* need negative lookup */
1327 qsilly.name = silly;
1328 qsilly.len = strlen(silly);
1329 if (dentry->d_inode) {
1330 error = NFS_PROTO(dir)->rename(dir, &dentry->d_name,
1332 nfs_mark_for_revalidate(dentry->d_inode);
1334 error = NFS_PROTO(dir)->rename(dir, &dentry->d_name,
1337 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1338 d_move(dentry, sdentry);
1339 error = nfs_async_unlink(dir, dentry);
1340 /* If we return 0 we don't unlink */
1348 * Remove a file after making sure there are no pending writes,
1349 * and after checking that the file has only one user.
1351 * We invalidate the attribute cache and free the inode prior to the operation
1352 * to avoid possible races if the server reuses the inode.
1354 static int nfs_safe_remove(struct dentry *dentry)
1356 struct inode *dir = dentry->d_parent->d_inode;
1357 struct inode *inode = dentry->d_inode;
1360 dfprintk(VFS, "NFS: safe_remove(%s/%s)\n",
1361 dentry->d_parent->d_name.name, dentry->d_name.name);
1363 /* If the dentry was sillyrenamed, we simply call d_delete() */
1364 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
1369 if (inode != NULL) {
1370 nfs_inode_return_delegation(inode);
1371 error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
1372 /* The VFS may want to delete this inode */
1375 nfs_mark_for_revalidate(inode);
1377 error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
1382 /* We do silly rename. In case sillyrename() returns -EBUSY, the inode
1383 * belongs to an active ".nfs..." file and we return -EBUSY.
1385 * If sillyrename() returns 0, we do nothing, otherwise we unlink.
1387 static int nfs_unlink(struct inode *dir, struct dentry *dentry)
1390 int need_rehash = 0;
1392 dfprintk(VFS, "NFS: unlink(%s/%ld, %s)\n", dir->i_sb->s_id,
1393 dir->i_ino, dentry->d_name.name);
1396 spin_lock(&dcache_lock);
1397 spin_lock(&dentry->d_lock);
1398 if (atomic_read(&dentry->d_count) > 1) {
1399 spin_unlock(&dentry->d_lock);
1400 spin_unlock(&dcache_lock);
1401 /* Start asynchronous writeout of the inode */
1402 write_inode_now(dentry->d_inode, 0);
1403 error = nfs_sillyrename(dir, dentry);
1407 if (!d_unhashed(dentry)) {
1411 spin_unlock(&dentry->d_lock);
1412 spin_unlock(&dcache_lock);
1413 error = nfs_safe_remove(dentry);
1415 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1416 } else if (need_rehash)
1423 * To create a symbolic link, most file systems instantiate a new inode,
1424 * add a page to it containing the path, then write it out to the disk
1425 * using prepare_write/commit_write.
1427 * Unfortunately the NFS client can't create the in-core inode first
1428 * because it needs a file handle to create an in-core inode (see
1429 * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the
1430 * symlink request has completed on the server.
1432 * So instead we allocate a raw page, copy the symname into it, then do
1433 * the SYMLINK request with the page as the buffer. If it succeeds, we
1434 * now have a new file handle and can instantiate an in-core NFS inode
1435 * and move the raw page into its mapping.
1437 static int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
1439 struct pagevec lru_pvec;
1443 unsigned int pathlen = strlen(symname);
1446 dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s)\n", dir->i_sb->s_id,
1447 dir->i_ino, dentry->d_name.name, symname);
1449 if (pathlen > PAGE_SIZE)
1450 return -ENAMETOOLONG;
1452 attr.ia_mode = S_IFLNK | S_IRWXUGO;
1453 attr.ia_valid = ATTR_MODE;
1457 page = alloc_page(GFP_HIGHUSER);
1463 kaddr = kmap_atomic(page, KM_USER0);
1464 memcpy(kaddr, symname, pathlen);
1465 if (pathlen < PAGE_SIZE)
1466 memset(kaddr + pathlen, 0, PAGE_SIZE - pathlen);
1467 kunmap_atomic(kaddr, KM_USER0);
1469 error = NFS_PROTO(dir)->symlink(dir, dentry, page, pathlen, &attr);
1471 dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s) error %d\n",
1472 dir->i_sb->s_id, dir->i_ino,
1473 dentry->d_name.name, symname, error);
1481 * No big deal if we can't add this page to the page cache here.
1482 * READLINK will get the missing page from the server if needed.
1484 pagevec_init(&lru_pvec, 0);
1485 if (!add_to_page_cache(page, dentry->d_inode->i_mapping, 0,
1487 pagevec_add(&lru_pvec, page);
1488 pagevec_lru_add(&lru_pvec);
1489 SetPageUptodate(page);
1499 nfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
1501 struct inode *inode = old_dentry->d_inode;
1504 dfprintk(VFS, "NFS: link(%s/%s -> %s/%s)\n",
1505 old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
1506 dentry->d_parent->d_name.name, dentry->d_name.name);
1510 error = NFS_PROTO(dir)->link(inode, dir, &dentry->d_name);
1512 atomic_inc(&inode->i_count);
1513 d_add(dentry, inode);
1521 * FIXME: Some nfsds, like the Linux user space nfsd, may generate a
1522 * different file handle for the same inode after a rename (e.g. when
1523 * moving to a different directory). A fail-safe method to do so would
1524 * be to look up old_dir/old_name, create a link to new_dir/new_name and
1525 * rename the old file using the sillyrename stuff. This way, the original
1526 * file in old_dir will go away when the last process iput()s the inode.
1530 * It actually works quite well. One needs to have the possibility for
1531 * at least one ".nfs..." file in each directory the file ever gets
1532 * moved or linked to which happens automagically with the new
1533 * implementation that only depends on the dcache stuff instead of
1534 * using the inode layer
1536 * Unfortunately, things are a little more complicated than indicated
1537 * above. For a cross-directory move, we want to make sure we can get
1538 * rid of the old inode after the operation. This means there must be
1539 * no pending writes (if it's a file), and the use count must be 1.
1540 * If these conditions are met, we can drop the dentries before doing
1543 static int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
1544 struct inode *new_dir, struct dentry *new_dentry)
1546 struct inode *old_inode = old_dentry->d_inode;
1547 struct inode *new_inode = new_dentry->d_inode;
1548 struct dentry *dentry = NULL, *rehash = NULL;
1552 * To prevent any new references to the target during the rename,
1553 * we unhash the dentry and free the inode in advance.
1556 if (!d_unhashed(new_dentry)) {
1558 rehash = new_dentry;
1561 dfprintk(VFS, "NFS: rename(%s/%s -> %s/%s, ct=%d)\n",
1562 old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
1563 new_dentry->d_parent->d_name.name, new_dentry->d_name.name,
1564 atomic_read(&new_dentry->d_count));
1567 * First check whether the target is busy ... we can't
1568 * safely do _any_ rename if the target is in use.
1570 * For files, make a copy of the dentry and then do a
1571 * silly-rename. If the silly-rename succeeds, the
1572 * copied dentry is hashed and becomes the new target.
1576 if (S_ISDIR(new_inode->i_mode)) {
1578 if (!S_ISDIR(old_inode->i_mode))
1580 } else if (atomic_read(&new_dentry->d_count) > 2) {
1582 /* copy the target dentry's name */
1583 dentry = d_alloc(new_dentry->d_parent,
1584 &new_dentry->d_name);
1588 /* silly-rename the existing target ... */
1589 err = nfs_sillyrename(new_dir, new_dentry);
1591 new_dentry = rehash = dentry;
1593 /* instantiate the replacement target */
1594 d_instantiate(new_dentry, NULL);
1595 } else if (atomic_read(&new_dentry->d_count) > 1)
1596 /* dentry still busy? */
1599 drop_nlink(new_inode);
1603 * ... prune child dentries and writebacks if needed.
1605 if (atomic_read(&old_dentry->d_count) > 1) {
1606 if (S_ISREG(old_inode->i_mode))
1607 nfs_wb_all(old_inode);
1608 shrink_dcache_parent(old_dentry);
1610 nfs_inode_return_delegation(old_inode);
1612 if (new_inode != NULL) {
1613 nfs_inode_return_delegation(new_inode);
1614 d_delete(new_dentry);
1617 error = NFS_PROTO(old_dir)->rename(old_dir, &old_dentry->d_name,
1618 new_dir, &new_dentry->d_name);
1619 nfs_mark_for_revalidate(old_inode);
1624 d_move(old_dentry, new_dentry);
1625 nfs_set_verifier(new_dentry,
1626 nfs_save_change_attribute(new_dir));
1629 /* new dentry created? */
1636 static DEFINE_SPINLOCK(nfs_access_lru_lock);
1637 static LIST_HEAD(nfs_access_lru_list);
1638 static atomic_long_t nfs_access_nr_entries;
1640 static void nfs_access_free_entry(struct nfs_access_entry *entry)
1642 put_rpccred(entry->cred);
1644 smp_mb__before_atomic_dec();
1645 atomic_long_dec(&nfs_access_nr_entries);
1646 smp_mb__after_atomic_dec();
1649 int nfs_access_cache_shrinker(int nr_to_scan, gfp_t gfp_mask)
1652 struct nfs_inode *nfsi;
1653 struct nfs_access_entry *cache;
1656 spin_lock(&nfs_access_lru_lock);
1657 list_for_each_entry(nfsi, &nfs_access_lru_list, access_cache_inode_lru) {
1658 struct inode *inode;
1660 if (nr_to_scan-- == 0)
1662 inode = igrab(&nfsi->vfs_inode);
1665 spin_lock(&inode->i_lock);
1666 if (list_empty(&nfsi->access_cache_entry_lru))
1667 goto remove_lru_entry;
1668 cache = list_entry(nfsi->access_cache_entry_lru.next,
1669 struct nfs_access_entry, lru);
1670 list_move(&cache->lru, &head);
1671 rb_erase(&cache->rb_node, &nfsi->access_cache);
1672 if (!list_empty(&nfsi->access_cache_entry_lru))
1673 list_move_tail(&nfsi->access_cache_inode_lru,
1674 &nfs_access_lru_list);
1677 list_del_init(&nfsi->access_cache_inode_lru);
1678 clear_bit(NFS_INO_ACL_LRU_SET, &nfsi->flags);
1680 spin_unlock(&inode->i_lock);
1681 spin_unlock(&nfs_access_lru_lock);
1685 spin_unlock(&nfs_access_lru_lock);
1686 while (!list_empty(&head)) {
1687 cache = list_entry(head.next, struct nfs_access_entry, lru);
1688 list_del(&cache->lru);
1689 nfs_access_free_entry(cache);
1691 return (atomic_long_read(&nfs_access_nr_entries) / 100) * sysctl_vfs_cache_pressure;
1694 static void __nfs_access_zap_cache(struct inode *inode)
1696 struct nfs_inode *nfsi = NFS_I(inode);
1697 struct rb_root *root_node = &nfsi->access_cache;
1698 struct rb_node *n, *dispose = NULL;
1699 struct nfs_access_entry *entry;
1701 /* Unhook entries from the cache */
1702 while ((n = rb_first(root_node)) != NULL) {
1703 entry = rb_entry(n, struct nfs_access_entry, rb_node);
1704 rb_erase(n, root_node);
1705 list_del(&entry->lru);
1706 n->rb_left = dispose;
1709 nfsi->cache_validity &= ~NFS_INO_INVALID_ACCESS;
1710 spin_unlock(&inode->i_lock);
1712 /* Now kill them all! */
1713 while (dispose != NULL) {
1715 dispose = n->rb_left;
1716 nfs_access_free_entry(rb_entry(n, struct nfs_access_entry, rb_node));
1720 void nfs_access_zap_cache(struct inode *inode)
1722 /* Remove from global LRU init */
1723 if (test_and_clear_bit(NFS_INO_ACL_LRU_SET, &NFS_FLAGS(inode))) {
1724 spin_lock(&nfs_access_lru_lock);
1725 list_del_init(&NFS_I(inode)->access_cache_inode_lru);
1726 spin_unlock(&nfs_access_lru_lock);
1729 spin_lock(&inode->i_lock);
1730 /* This will release the spinlock */
1731 __nfs_access_zap_cache(inode);
1734 static struct nfs_access_entry *nfs_access_search_rbtree(struct inode *inode, struct rpc_cred *cred)
1736 struct rb_node *n = NFS_I(inode)->access_cache.rb_node;
1737 struct nfs_access_entry *entry;
1740 entry = rb_entry(n, struct nfs_access_entry, rb_node);
1742 if (cred < entry->cred)
1744 else if (cred > entry->cred)
1752 static int nfs_access_get_cached(struct inode *inode, struct rpc_cred *cred, struct nfs_access_entry *res)
1754 struct nfs_inode *nfsi = NFS_I(inode);
1755 struct nfs_access_entry *cache;
1758 spin_lock(&inode->i_lock);
1759 if (nfsi->cache_validity & NFS_INO_INVALID_ACCESS)
1761 cache = nfs_access_search_rbtree(inode, cred);
1764 if (!time_in_range(jiffies, cache->jiffies, cache->jiffies + NFS_ATTRTIMEO(inode)))
1766 res->jiffies = cache->jiffies;
1767 res->cred = cache->cred;
1768 res->mask = cache->mask;
1769 list_move_tail(&cache->lru, &nfsi->access_cache_entry_lru);
1772 spin_unlock(&inode->i_lock);
1775 rb_erase(&cache->rb_node, &nfsi->access_cache);
1776 list_del(&cache->lru);
1777 spin_unlock(&inode->i_lock);
1778 nfs_access_free_entry(cache);
1781 /* This will release the spinlock */
1782 __nfs_access_zap_cache(inode);
1786 static void nfs_access_add_rbtree(struct inode *inode, struct nfs_access_entry *set)
1788 struct nfs_inode *nfsi = NFS_I(inode);
1789 struct rb_root *root_node = &nfsi->access_cache;
1790 struct rb_node **p = &root_node->rb_node;
1791 struct rb_node *parent = NULL;
1792 struct nfs_access_entry *entry;
1794 spin_lock(&inode->i_lock);
1795 while (*p != NULL) {
1797 entry = rb_entry(parent, struct nfs_access_entry, rb_node);
1799 if (set->cred < entry->cred)
1800 p = &parent->rb_left;
1801 else if (set->cred > entry->cred)
1802 p = &parent->rb_right;
1806 rb_link_node(&set->rb_node, parent, p);
1807 rb_insert_color(&set->rb_node, root_node);
1808 list_add_tail(&set->lru, &nfsi->access_cache_entry_lru);
1809 spin_unlock(&inode->i_lock);
1812 rb_replace_node(parent, &set->rb_node, root_node);
1813 list_add_tail(&set->lru, &nfsi->access_cache_entry_lru);
1814 list_del(&entry->lru);
1815 spin_unlock(&inode->i_lock);
1816 nfs_access_free_entry(entry);
1819 static void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set)
1821 struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_KERNEL);
1824 RB_CLEAR_NODE(&cache->rb_node);
1825 cache->jiffies = set->jiffies;
1826 cache->cred = get_rpccred(set->cred);
1827 cache->mask = set->mask;
1829 nfs_access_add_rbtree(inode, cache);
1831 /* Update accounting */
1832 smp_mb__before_atomic_inc();
1833 atomic_long_inc(&nfs_access_nr_entries);
1834 smp_mb__after_atomic_inc();
1836 /* Add inode to global LRU list */
1837 if (!test_and_set_bit(NFS_INO_ACL_LRU_SET, &NFS_FLAGS(inode))) {
1838 spin_lock(&nfs_access_lru_lock);
1839 list_add_tail(&NFS_I(inode)->access_cache_inode_lru, &nfs_access_lru_list);
1840 spin_unlock(&nfs_access_lru_lock);
1844 static int nfs_do_access(struct inode *inode, struct rpc_cred *cred, int mask)
1846 struct nfs_access_entry cache;
1849 status = nfs_access_get_cached(inode, cred, &cache);
1853 /* Be clever: ask server to check for all possible rights */
1854 cache.mask = MAY_EXEC | MAY_WRITE | MAY_READ;
1856 cache.jiffies = jiffies;
1857 status = NFS_PROTO(inode)->access(inode, &cache);
1860 nfs_access_add_cache(inode, &cache);
1862 if ((cache.mask & mask) == mask)
1867 static int nfs_open_permission_mask(int openflags)
1871 if (openflags & FMODE_READ)
1873 if (openflags & FMODE_WRITE)
1875 if (openflags & FMODE_EXEC)
1880 int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags)
1882 return nfs_do_access(inode, cred, nfs_open_permission_mask(openflags));
1885 int nfs_permission(struct inode *inode, int mask, struct nameidata *nd)
1887 struct rpc_cred *cred;
1890 nfs_inc_stats(inode, NFSIOS_VFSACCESS);
1894 /* Is this sys_access() ? */
1895 if (nd != NULL && (nd->flags & LOOKUP_ACCESS))
1898 switch (inode->i_mode & S_IFMT) {
1902 /* NFSv4 has atomic_open... */
1903 if (nfs_server_capable(inode, NFS_CAP_ATOMIC_OPEN)
1905 && (nd->flags & LOOKUP_OPEN))
1910 * Optimize away all write operations, since the server
1911 * will check permissions when we perform the op.
1913 if ((mask & MAY_WRITE) && !(mask & MAY_READ))
1920 if (!NFS_PROTO(inode)->access)
1923 cred = rpcauth_lookupcred(NFS_CLIENT(inode)->cl_auth, 0);
1924 if (!IS_ERR(cred)) {
1925 res = nfs_do_access(inode, cred, mask);
1928 res = PTR_ERR(cred);
1931 dfprintk(VFS, "NFS: permission(%s/%ld), mask=0x%x, res=%d\n",
1932 inode->i_sb->s_id, inode->i_ino, mask, res);
1935 res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
1937 res = generic_permission(inode, mask, NULL);
1944 * version-control: t
1945 * kept-new-versions: 5