blob: e257172d438c08afe374c99fe0e7c80af51efe6c [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * linux/fs/nfs/dir.c
3 *
4 * Copyright (C) 1992 Rick Sladkey
5 *
6 * nfs directory handling functions
7 *
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
18 */
19
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>
27#include <linux/mm.h>
28#include <linux/sunrpc/clnt.h>
29#include <linux/nfs_fs.h>
30#include <linux/nfs_mount.h>
31#include <linux/pagemap.h>
Chuck Lever873101b2006-08-22 20:06:23 -040032#include <linux/pagevec.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070033#include <linux/namei.h>
David Howells54ceac42006-08-22 20:06:13 -040034#include <linux/mount.h>
Alexey Dobriyane8edc6e2007-05-21 01:22:52 +040035#include <linux/sched.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070036
Trond Myklebust4ce79712005-06-22 17:16:21 +000037#include "nfs4_fs.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070038#include "delegation.h"
Chuck Lever91d5b472006-03-20 13:44:14 -050039#include "iostat.h"
Adrian Bunk4c30d562007-11-21 15:04:31 -080040#include "internal.h"
Linus Torvalds1da177e2005-04-16 15:20:36 -070041
Linus Torvalds1da177e2005-04-16 15:20:36 -070042/* #define NFS_DEBUG_VERBOSE 1 */
43
44static int nfs_opendir(struct inode *, struct file *);
45static int nfs_readdir(struct file *, void *, filldir_t);
46static struct dentry *nfs_lookup(struct inode *, struct dentry *, struct nameidata *);
47static int nfs_create(struct inode *, struct dentry *, int, struct nameidata *);
48static int nfs_mkdir(struct inode *, struct dentry *, int);
49static int nfs_rmdir(struct inode *, struct dentry *);
50static int nfs_unlink(struct inode *, struct dentry *);
51static int nfs_symlink(struct inode *, struct dentry *, const char *);
52static int nfs_link(struct dentry *, struct inode *, struct dentry *);
53static int nfs_mknod(struct inode *, struct dentry *, int, dev_t);
54static int nfs_rename(struct inode *, struct dentry *,
55 struct inode *, struct dentry *);
Christoph Hellwig7ea80852010-05-26 17:53:25 +020056static int nfs_fsync_dir(struct file *, int);
Trond Myklebustf0dd2132005-06-22 17:16:29 +000057static loff_t nfs_llseek_dir(struct file *, loff_t, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -070058
Arjan van de Ven4b6f5d22006-03-28 01:56:42 -080059const struct file_operations nfs_dir_operations = {
Trond Myklebustf0dd2132005-06-22 17:16:29 +000060 .llseek = nfs_llseek_dir,
Linus Torvalds1da177e2005-04-16 15:20:36 -070061 .read = generic_read_dir,
62 .readdir = nfs_readdir,
63 .open = nfs_opendir,
64 .release = nfs_release,
65 .fsync = nfs_fsync_dir,
66};
67
Arjan van de Ven92e1d5b2007-02-12 00:55:39 -080068const struct inode_operations nfs_dir_inode_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 .create = nfs_create,
70 .lookup = nfs_lookup,
71 .link = nfs_link,
72 .unlink = nfs_unlink,
73 .symlink = nfs_symlink,
74 .mkdir = nfs_mkdir,
75 .rmdir = nfs_rmdir,
76 .mknod = nfs_mknod,
77 .rename = nfs_rename,
78 .permission = nfs_permission,
79 .getattr = nfs_getattr,
80 .setattr = nfs_setattr,
81};
82
Andreas Gruenbacherb7fa0552005-06-22 17:16:27 +000083#ifdef CONFIG_NFS_V3
Arjan van de Ven92e1d5b2007-02-12 00:55:39 -080084const struct inode_operations nfs3_dir_inode_operations = {
Andreas Gruenbacherb7fa0552005-06-22 17:16:27 +000085 .create = nfs_create,
86 .lookup = nfs_lookup,
87 .link = nfs_link,
88 .unlink = nfs_unlink,
89 .symlink = nfs_symlink,
90 .mkdir = nfs_mkdir,
91 .rmdir = nfs_rmdir,
92 .mknod = nfs_mknod,
93 .rename = nfs_rename,
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,
101};
102#endif /* CONFIG_NFS_V3 */
103
Linus Torvalds1da177e2005-04-16 15:20:36 -0700104#ifdef CONFIG_NFS_V4
105
106static struct dentry *nfs_atomic_lookup(struct inode *, struct dentry *, struct nameidata *);
Arjan van de Ven92e1d5b2007-02-12 00:55:39 -0800107const struct inode_operations nfs4_dir_inode_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700108 .create = nfs_create,
109 .lookup = nfs_atomic_lookup,
110 .link = nfs_link,
111 .unlink = nfs_unlink,
112 .symlink = nfs_symlink,
113 .mkdir = nfs_mkdir,
114 .rmdir = nfs_rmdir,
115 .mknod = nfs_mknod,
116 .rename = nfs_rename,
117 .permission = nfs_permission,
118 .getattr = nfs_getattr,
119 .setattr = nfs_setattr,
J. Bruce Fields6b3b5492005-06-22 17:16:22 +0000120 .getxattr = nfs4_getxattr,
121 .setxattr = nfs4_setxattr,
122 .listxattr = nfs4_listxattr,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700123};
124
125#endif /* CONFIG_NFS_V4 */
126
127/*
128 * Open file
129 */
130static int
131nfs_opendir(struct inode *inode, struct file *filp)
132{
Carsten Otte7451c4f2006-04-19 13:06:37 -0400133 int res;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700134
Chuck Lever6da24bc2008-06-11 17:55:58 -0400135 dfprintk(FILE, "NFS: open dir(%s/%s)\n",
Chuck Levercc0dd2d2008-06-11 17:55:42 -0400136 filp->f_path.dentry->d_parent->d_name.name,
137 filp->f_path.dentry->d_name.name);
138
139 nfs_inc_stats(inode, NFSIOS_VFSOPEN);
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500140
Linus Torvalds1da177e2005-04-16 15:20:36 -0700141 /* Call generic open code in order to cache credentials */
Carsten Otte7451c4f2006-04-19 13:06:37 -0400142 res = nfs_open(inode, filp);
Neil Brownf5a73672010-08-10 10:20:05 -0400143 if (filp->f_path.dentry == filp->f_path.mnt->mnt_root) {
144 /* This is a mountpoint, so d_revalidate will never
145 * have been called, so we need to refresh the
146 * inode (for close-open consistency) ourselves.
147 */
148 __nfs_revalidate_inode(NFS_SERVER(inode), inode);
149 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150 return res;
151}
152
Al Viro0dbb4c62006-10-19 23:28:49 -0700153typedef __be32 * (*decode_dirent_t)(__be32 *, struct nfs_entry *, int);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700154typedef struct {
155 struct file *file;
156 struct page *page;
157 unsigned long page_index;
Al Viro0dbb4c62006-10-19 23:28:49 -0700158 __be32 *ptr;
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000159 u64 *dir_cookie;
160 loff_t current_index;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700161 struct nfs_entry *entry;
162 decode_dirent_t decode;
163 int plus;
Neil Brown1f4eab72007-04-16 09:35:27 +1000164 unsigned long timestamp;
Trond Myklebust4704f0e2008-10-14 19:16:07 -0400165 unsigned long gencount;
Neil Brown1f4eab72007-04-16 09:35:27 +1000166 int timestamp_valid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700167} nfs_readdir_descriptor_t;
168
169/* Now we cache directories properly, by stuffing the dirent
170 * data directly in the page cache.
171 *
172 * Inode invalidation due to refresh etc. takes care of
173 * _everything_, no sloppy entry flushing logic, no extraneous
174 * copying, network direct to page cache, the way it was meant
175 * to be.
176 *
177 * NOTE: Dirent information verification is done always by the
178 * page-in of the RPC reply, nowhere else, this simplies
179 * things substantially.
180 */
181static
182int nfs_readdir_filler(nfs_readdir_descriptor_t *desc, struct page *page)
183{
184 struct file *file = desc->file;
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800185 struct inode *inode = file->f_path.dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700186 struct rpc_cred *cred = nfs_file_cred(file);
Trond Myklebust4704f0e2008-10-14 19:16:07 -0400187 unsigned long timestamp, gencount;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700188 int error;
189
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500190 dfprintk(DIRCACHE, "NFS: %s: reading cookie %Lu into page %lu\n",
Harvey Harrison3110ff82008-05-02 13:42:44 -0700191 __func__, (long long)desc->entry->cookie,
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500192 page->index);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700193
194 again:
195 timestamp = jiffies;
Trond Myklebust4704f0e2008-10-14 19:16:07 -0400196 gencount = nfs_inc_attr_generation_counter();
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800197 error = NFS_PROTO(inode)->readdir(file->f_path.dentry, cred, desc->entry->cookie, page,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700198 NFS_SERVER(inode)->dtsize, desc->plus);
199 if (error < 0) {
200 /* We requested READDIRPLUS, but the server doesn't grok it */
201 if (error == -ENOTSUPP && desc->plus) {
202 NFS_SERVER(inode)->caps &= ~NFS_CAP_READDIRPLUS;
Benny Halevy3a10c302008-01-23 08:58:59 +0200203 clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204 desc->plus = 0;
205 goto again;
206 }
207 goto error;
208 }
Neil Brown1f4eab72007-04-16 09:35:27 +1000209 desc->timestamp = timestamp;
Trond Myklebust4704f0e2008-10-14 19:16:07 -0400210 desc->gencount = gencount;
Neil Brown1f4eab72007-04-16 09:35:27 +1000211 desc->timestamp_valid = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212 SetPageUptodate(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700213 /* Ensure consistent page alignment of the data.
214 * Note: assumes we have exclusive access to this mapping either
Jes Sorensen1b1dcc12006-01-09 15:59:24 -0800215 * through inode->i_mutex or some other mechanism.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700216 */
Trond Myklebust2aac05a2008-07-07 13:26:10 -0400217 if (invalidate_inode_pages2_range(inode->i_mapping, page->index + 1, -1) < 0) {
Trond Myklebustcd9ae2b2006-10-19 23:28:40 -0700218 /* Should never happen */
219 nfs_zap_mapping(inode, inode->i_mapping);
220 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700221 unlock_page(page);
222 return 0;
223 error:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224 unlock_page(page);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700225 return -EIO;
226}
227
228static inline
229int dir_decode(nfs_readdir_descriptor_t *desc)
230{
Al Viro0dbb4c62006-10-19 23:28:49 -0700231 __be32 *p = desc->ptr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700232 p = desc->decode(p, desc->entry, desc->plus);
233 if (IS_ERR(p))
234 return PTR_ERR(p);
235 desc->ptr = p;
Trond Myklebust4704f0e2008-10-14 19:16:07 -0400236 if (desc->timestamp_valid) {
Neil Brown1f4eab72007-04-16 09:35:27 +1000237 desc->entry->fattr->time_start = desc->timestamp;
Trond Myklebust4704f0e2008-10-14 19:16:07 -0400238 desc->entry->fattr->gencount = desc->gencount;
239 } else
Neil Brown1f4eab72007-04-16 09:35:27 +1000240 desc->entry->fattr->valid &= ~NFS_ATTR_FATTR;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700241 return 0;
242}
243
244static inline
245void dir_page_release(nfs_readdir_descriptor_t *desc)
246{
247 kunmap(desc->page);
248 page_cache_release(desc->page);
249 desc->page = NULL;
250 desc->ptr = NULL;
251}
252
253/*
254 * Given a pointer to a buffer that has already been filled by a call
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000255 * to readdir, find the next entry with cookie '*desc->dir_cookie'.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700256 *
257 * If the end of the buffer has been reached, return -EAGAIN, if not,
258 * return the offset within the buffer of the next entry to be
259 * read.
260 */
261static inline
Olivier Galibert00a92642005-06-22 17:16:29 +0000262int find_dirent(nfs_readdir_descriptor_t *desc)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700263{
264 struct nfs_entry *entry = desc->entry;
265 int loop_count = 0,
266 status;
267
268 while((status = dir_decode(desc)) == 0) {
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500269 dfprintk(DIRCACHE, "NFS: %s: examining cookie %Lu\n",
Harvey Harrison3110ff82008-05-02 13:42:44 -0700270 __func__, (unsigned long long)entry->cookie);
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000271 if (entry->prev_cookie == *desc->dir_cookie)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700272 break;
273 if (loop_count++ > 200) {
274 loop_count = 0;
275 schedule();
276 }
277 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278 return status;
279}
280
281/*
Olivier Galibert00a92642005-06-22 17:16:29 +0000282 * Given a pointer to a buffer that has already been filled by a call
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000283 * to readdir, find the entry at offset 'desc->file->f_pos'.
Olivier Galibert00a92642005-06-22 17:16:29 +0000284 *
285 * If the end of the buffer has been reached, return -EAGAIN, if not,
286 * return the offset within the buffer of the next entry to be
287 * read.
288 */
289static inline
290int find_dirent_index(nfs_readdir_descriptor_t *desc)
291{
292 struct nfs_entry *entry = desc->entry;
293 int loop_count = 0,
294 status;
295
296 for(;;) {
297 status = dir_decode(desc);
298 if (status)
299 break;
300
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500301 dfprintk(DIRCACHE, "NFS: found cookie %Lu at index %Ld\n",
302 (unsigned long long)entry->cookie, desc->current_index);
Olivier Galibert00a92642005-06-22 17:16:29 +0000303
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000304 if (desc->file->f_pos == desc->current_index) {
305 *desc->dir_cookie = entry->cookie;
Olivier Galibert00a92642005-06-22 17:16:29 +0000306 break;
307 }
308 desc->current_index++;
309 if (loop_count++ > 200) {
310 loop_count = 0;
311 schedule();
312 }
313 }
Olivier Galibert00a92642005-06-22 17:16:29 +0000314 return status;
315}
316
317/*
318 * Find the given page, and call find_dirent() or find_dirent_index in
319 * order to try to return the next entry.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700320 */
321static inline
322int find_dirent_page(nfs_readdir_descriptor_t *desc)
323{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800324 struct inode *inode = desc->file->f_path.dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 struct page *page;
326 int status;
327
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500328 dfprintk(DIRCACHE, "NFS: %s: searching page %ld for target %Lu\n",
Harvey Harrison3110ff82008-05-02 13:42:44 -0700329 __func__, desc->page_index,
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500330 (long long) *desc->dir_cookie);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700331
Neil Brown1f4eab72007-04-16 09:35:27 +1000332 /* If we find the page in the page_cache, we cannot be sure
333 * how fresh the data is, so we will ignore readdir_plus attributes.
334 */
335 desc->timestamp_valid = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700336 page = read_cache_page(inode->i_mapping, desc->page_index,
337 (filler_t *)nfs_readdir_filler, desc);
338 if (IS_ERR(page)) {
339 status = PTR_ERR(page);
340 goto out;
341 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700342
343 /* NOTE: Someone else may have changed the READDIRPLUS flag */
344 desc->page = page;
345 desc->ptr = kmap(page); /* matching kunmap in nfs_do_filldir */
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000346 if (*desc->dir_cookie != 0)
Olivier Galibert00a92642005-06-22 17:16:29 +0000347 status = find_dirent(desc);
348 else
349 status = find_dirent_index(desc);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700350 if (status < 0)
351 dir_page_release(desc);
352 out:
Harvey Harrison3110ff82008-05-02 13:42:44 -0700353 dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __func__, status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700354 return status;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700355}
356
357/*
358 * Recurse through the page cache pages, and return a
359 * filled nfs_entry structure of the next directory entry if possible.
360 *
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000361 * The target for the search is '*desc->dir_cookie' if non-0,
362 * 'desc->file->f_pos' otherwise
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363 */
364static inline
365int readdir_search_pagecache(nfs_readdir_descriptor_t *desc)
366{
367 int loop_count = 0;
368 int res;
369
Olivier Galibert00a92642005-06-22 17:16:29 +0000370 /* Always search-by-index from the beginning of the cache */
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000371 if (*desc->dir_cookie == 0) {
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500372 dfprintk(DIRCACHE, "NFS: readdir_search_pagecache() searching for offset %Ld\n",
373 (long long)desc->file->f_pos);
Olivier Galibert00a92642005-06-22 17:16:29 +0000374 desc->page_index = 0;
375 desc->entry->cookie = desc->entry->prev_cookie = 0;
376 desc->entry->eof = 0;
377 desc->current_index = 0;
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000378 } else
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500379 dfprintk(DIRCACHE, "NFS: readdir_search_pagecache() searching for cookie %Lu\n",
380 (unsigned long long)*desc->dir_cookie);
Olivier Galibert00a92642005-06-22 17:16:29 +0000381
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382 for (;;) {
383 res = find_dirent_page(desc);
384 if (res != -EAGAIN)
385 break;
386 /* Align to beginning of next page */
387 desc->page_index ++;
388 if (loop_count++ > 200) {
389 loop_count = 0;
390 schedule();
391 }
392 }
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500393
Harvey Harrison3110ff82008-05-02 13:42:44 -0700394 dfprintk(DIRCACHE, "NFS: %s: returns %d\n", __func__, res);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700395 return res;
396}
397
398static inline unsigned int dt_type(struct inode *inode)
399{
400 return (inode->i_mode >> 12) & 15;
401}
402
403static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc);
404
405/*
406 * Once we've found the start of the dirent within a page: fill 'er up...
407 */
408static
409int nfs_do_filldir(nfs_readdir_descriptor_t *desc, void *dirent,
410 filldir_t filldir)
411{
412 struct file *file = desc->file;
413 struct nfs_entry *entry = desc->entry;
414 struct dentry *dentry = NULL;
Peter Staubach4e769b92007-08-03 15:07:10 -0400415 u64 fileid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700416 int loop_count = 0,
417 res;
418
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500419 dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling starting @ cookie %Lu\n",
420 (unsigned long long)entry->cookie);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700421
422 for(;;) {
423 unsigned d_type = DT_UNKNOWN;
424 /* Note: entry->prev_cookie contains the cookie for
425 * retrieving the current dirent on the server */
Peter Staubach4e769b92007-08-03 15:07:10 -0400426 fileid = entry->ino;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700427
428 /* Get a dentry if we have one */
429 if (dentry != NULL)
430 dput(dentry);
431 dentry = nfs_readdir_lookup(desc);
432
433 /* Use readdirplus info */
434 if (dentry != NULL && dentry->d_inode != NULL) {
435 d_type = dt_type(dentry->d_inode);
Peter Staubach4e769b92007-08-03 15:07:10 -0400436 fileid = NFS_FILEID(dentry->d_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700437 }
438
439 res = filldir(dirent, entry->name, entry->len,
Trond Myklebustf43bf0b2007-10-09 12:01:04 -0400440 file->f_pos, nfs_compat_user_ino64(fileid),
441 d_type);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700442 if (res < 0)
443 break;
Olivier Galibert00a92642005-06-22 17:16:29 +0000444 file->f_pos++;
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000445 *desc->dir_cookie = entry->cookie;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700446 if (dir_decode(desc) != 0) {
447 desc->page_index ++;
448 break;
449 }
450 if (loop_count++ > 200) {
451 loop_count = 0;
452 schedule();
453 }
454 }
455 dir_page_release(desc);
456 if (dentry != NULL)
457 dput(dentry);
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500458 dfprintk(DIRCACHE, "NFS: nfs_do_filldir() filling ended @ cookie %Lu; returning = %d\n",
459 (unsigned long long)*desc->dir_cookie, res);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700460 return res;
461}
462
463/*
464 * If we cannot find a cookie in our cache, we suspect that this is
465 * because it points to a deleted file, so we ask the server to return
466 * whatever it thinks is the next entry. We then feed this to filldir.
467 * If all goes well, we should then be able to find our way round the
468 * cache on the next call to readdir_search_pagecache();
469 *
470 * NOTE: we cannot add the anonymous page to the pagecache because
471 * the data it contains might not be page aligned. Besides,
472 * we should already have a complete representation of the
473 * directory in the page cache by the time we get here.
474 */
475static inline
476int uncached_readdir(nfs_readdir_descriptor_t *desc, void *dirent,
477 filldir_t filldir)
478{
479 struct file *file = desc->file;
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800480 struct inode *inode = file->f_path.dentry->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700481 struct rpc_cred *cred = nfs_file_cred(file);
482 struct page *page = NULL;
483 int status;
Trond Myklebust4704f0e2008-10-14 19:16:07 -0400484 unsigned long timestamp, gencount;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700485
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500486 dfprintk(DIRCACHE, "NFS: uncached_readdir() searching for cookie %Lu\n",
487 (unsigned long long)*desc->dir_cookie);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700488
489 page = alloc_page(GFP_HIGHUSER);
490 if (!page) {
491 status = -ENOMEM;
492 goto out;
493 }
Neil Brown1f4eab72007-04-16 09:35:27 +1000494 timestamp = jiffies;
Trond Myklebust4704f0e2008-10-14 19:16:07 -0400495 gencount = nfs_inc_attr_generation_counter();
Jeff Layton25606652008-02-12 06:49:01 -0500496 status = NFS_PROTO(inode)->readdir(file->f_path.dentry, cred,
497 *desc->dir_cookie, page,
Linus Torvalds1da177e2005-04-16 15:20:36 -0700498 NFS_SERVER(inode)->dtsize,
499 desc->plus);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700500 desc->page = page;
501 desc->ptr = kmap(page); /* matching kunmap in nfs_do_filldir */
Jeff Layton25606652008-02-12 06:49:01 -0500502 if (status >= 0) {
Neil Brown1f4eab72007-04-16 09:35:27 +1000503 desc->timestamp = timestamp;
Trond Myklebust4704f0e2008-10-14 19:16:07 -0400504 desc->gencount = gencount;
Neil Brown1f4eab72007-04-16 09:35:27 +1000505 desc->timestamp_valid = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700506 if ((status = dir_decode(desc)) == 0)
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000507 desc->entry->prev_cookie = *desc->dir_cookie;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700508 } else
509 status = -EIO;
510 if (status < 0)
511 goto out_release;
512
513 status = nfs_do_filldir(desc, dirent, filldir);
514
515 /* Reset read descriptor so it searches the page cache from
516 * the start upon the next call to readdir_search_pagecache() */
517 desc->page_index = 0;
518 desc->entry->cookie = desc->entry->prev_cookie = 0;
519 desc->entry->eof = 0;
520 out:
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500521 dfprintk(DIRCACHE, "NFS: %s: returns %d\n",
Harvey Harrison3110ff82008-05-02 13:42:44 -0700522 __func__, status);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700523 return status;
524 out_release:
525 dir_page_release(desc);
526 goto out;
527}
528
Olivier Galibert00a92642005-06-22 17:16:29 +0000529/* The file offset position represents the dirent entry number. A
530 last cookie cache takes care of the common case of reading the
531 whole directory.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700532 */
533static int nfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
534{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -0800535 struct dentry *dentry = filp->f_path.dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700536 struct inode *inode = dentry->d_inode;
537 nfs_readdir_descriptor_t my_desc,
538 *desc = &my_desc;
539 struct nfs_entry my_entry;
Trond Myklebustaa49b4c2010-04-16 16:22:49 -0400540 int res = -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700541
Chuck Lever6da24bc2008-06-11 17:55:58 -0400542 dfprintk(FILE, "NFS: readdir(%s/%s) starting at cookie %llu\n",
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500543 dentry->d_parent->d_name.name, dentry->d_name.name,
544 (long long)filp->f_pos);
Chuck Lever91d5b472006-03-20 13:44:14 -0500545 nfs_inc_stats(inode, NFSIOS_VFSGETDENTS);
546
Linus Torvalds1da177e2005-04-16 15:20:36 -0700547 /*
Olivier Galibert00a92642005-06-22 17:16:29 +0000548 * filp->f_pos points to the dirent entry number.
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000549 * *desc->dir_cookie has the cookie for the next entry. We have
Olivier Galibert00a92642005-06-22 17:16:29 +0000550 * to either find the entry with the appropriate number or
551 * revalidate the cookie.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700552 */
553 memset(desc, 0, sizeof(*desc));
554
555 desc->file = filp;
Trond Myklebustcd3758e2007-08-10 17:44:32 -0400556 desc->dir_cookie = &nfs_file_open_context(filp)->dir_cookie;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700557 desc->decode = NFS_PROTO(inode)->decode_dirent;
558 desc->plus = NFS_USE_READDIRPLUS(inode);
559
560 my_entry.cookie = my_entry.prev_cookie = 0;
561 my_entry.eof = 0;
Trond Myklebustaa49b4c2010-04-16 16:22:49 -0400562 my_entry.fh = nfs_alloc_fhandle();
563 my_entry.fattr = nfs_alloc_fattr();
564 if (my_entry.fh == NULL || my_entry.fattr == NULL)
565 goto out_alloc_failed;
566
Linus Torvalds1da177e2005-04-16 15:20:36 -0700567 desc->entry = &my_entry;
568
Trond Myklebust565277f2007-10-15 18:17:53 -0400569 nfs_block_sillyrename(dentry);
Trond Myklebust1cda7072010-02-19 17:03:30 -0800570 res = nfs_revalidate_mapping(inode, filp->f_mapping);
Trond Myklebustfccca7f2008-01-26 17:37:47 -0500571 if (res < 0)
572 goto out;
573
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574 while(!desc->entry->eof) {
575 res = readdir_search_pagecache(desc);
Olivier Galibert00a92642005-06-22 17:16:29 +0000576
Linus Torvalds1da177e2005-04-16 15:20:36 -0700577 if (res == -EBADCOOKIE) {
578 /* This means either end of directory */
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000579 if (*desc->dir_cookie && desc->entry->cookie != *desc->dir_cookie) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700580 /* Or that the server has 'lost' a cookie */
581 res = uncached_readdir(desc, dirent, filldir);
582 if (res >= 0)
583 continue;
584 }
585 res = 0;
586 break;
587 }
588 if (res == -ETOOSMALL && desc->plus) {
Benny Halevy3a10c302008-01-23 08:58:59 +0200589 clear_bit(NFS_INO_ADVISE_RDPLUS, &NFS_I(inode)->flags);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700590 nfs_zap_caches(inode);
591 desc->plus = 0;
592 desc->entry->eof = 0;
593 continue;
594 }
595 if (res < 0)
596 break;
597
598 res = nfs_do_filldir(desc, dirent, filldir);
599 if (res < 0) {
600 res = 0;
601 break;
602 }
603 }
Trond Myklebustfccca7f2008-01-26 17:37:47 -0500604out:
Trond Myklebust565277f2007-10-15 18:17:53 -0400605 nfs_unblock_sillyrename(dentry);
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500606 if (res > 0)
607 res = 0;
Trond Myklebustaa49b4c2010-04-16 16:22:49 -0400608out_alloc_failed:
609 nfs_free_fattr(my_entry.fattr);
610 nfs_free_fhandle(my_entry.fh);
611 dfprintk(FILE, "NFS: readdir(%s/%s) returns %d\n",
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500612 dentry->d_parent->d_name.name, dentry->d_name.name,
613 res);
614 return res;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615}
616
Trond Myklebust10afec92007-05-14 17:16:04 -0400617static loff_t nfs_llseek_dir(struct file *filp, loff_t offset, int origin)
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000618{
Chuck Leverb84e06c2008-06-11 17:55:34 -0400619 struct dentry *dentry = filp->f_path.dentry;
620 struct inode *inode = dentry->d_inode;
621
Chuck Lever6da24bc2008-06-11 17:55:58 -0400622 dfprintk(FILE, "NFS: llseek dir(%s/%s, %lld, %d)\n",
Chuck Leverb84e06c2008-06-11 17:55:34 -0400623 dentry->d_parent->d_name.name,
624 dentry->d_name.name,
625 offset, origin);
626
627 mutex_lock(&inode->i_mutex);
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000628 switch (origin) {
629 case 1:
630 offset += filp->f_pos;
631 case 0:
632 if (offset >= 0)
633 break;
634 default:
635 offset = -EINVAL;
636 goto out;
637 }
638 if (offset != filp->f_pos) {
639 filp->f_pos = offset;
Trond Myklebustcd3758e2007-08-10 17:44:32 -0400640 nfs_file_open_context(filp)->dir_cookie = 0;
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000641 }
642out:
Chuck Leverb84e06c2008-06-11 17:55:34 -0400643 mutex_unlock(&inode->i_mutex);
Trond Myklebustf0dd2132005-06-22 17:16:29 +0000644 return offset;
645}
646
Linus Torvalds1da177e2005-04-16 15:20:36 -0700647/*
648 * All directory operations under NFS are synchronous, so fsync()
649 * is a dummy operation.
650 */
Christoph Hellwig7ea80852010-05-26 17:53:25 +0200651static int nfs_fsync_dir(struct file *filp, int datasync)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652{
Christoph Hellwig7ea80852010-05-26 17:53:25 +0200653 struct dentry *dentry = filp->f_path.dentry;
654
Chuck Lever6da24bc2008-06-11 17:55:58 -0400655 dfprintk(FILE, "NFS: fsync dir(%s/%s) datasync %d\n",
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500656 dentry->d_parent->d_name.name, dentry->d_name.name,
657 datasync);
658
Chuck Lever54917782008-05-27 16:29:07 -0400659 nfs_inc_stats(dentry->d_inode, NFSIOS_VFSFSYNC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700660 return 0;
661}
662
Trond Myklebustbfc69a42007-10-15 18:18:29 -0400663/**
664 * nfs_force_lookup_revalidate - Mark the directory as having changed
665 * @dir - pointer to directory inode
666 *
667 * This forces the revalidation code in nfs_lookup_revalidate() to do a
668 * full lookup on all child dentries of 'dir' whenever a change occurs
669 * on the server that might have invalidated our dcache.
670 *
671 * The caller should be holding dir->i_lock
672 */
673void nfs_force_lookup_revalidate(struct inode *dir)
674{
Trond Myklebust011935a02008-10-14 19:24:50 -0400675 NFS_I(dir)->cache_change_attribute++;
Trond Myklebustbfc69a42007-10-15 18:18:29 -0400676}
677
Linus Torvalds1da177e2005-04-16 15:20:36 -0700678/*
679 * A check for whether or not the parent directory has changed.
680 * In the case it has, we assume that the dentries are untrustworthy
681 * and may need to be looked up again.
682 */
Trond Myklebustc79ba782007-01-31 08:16:24 -0500683static int nfs_check_verifier(struct inode *dir, struct dentry *dentry)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684{
685 if (IS_ROOT(dentry))
686 return 1;
Trond Myklebust4eec9522008-07-15 17:58:13 -0400687 if (NFS_SERVER(dir)->flags & NFS_MOUNT_LOOKUP_CACHE_NONE)
688 return 0;
Trond Myklebustf2c77f42007-10-02 12:54:39 -0400689 if (!nfs_verify_change_attribute(dir, dentry->d_time))
690 return 0;
691 /* Revalidate nfsi->cache_change_attribute before we declare a match */
692 if (nfs_revalidate_inode(NFS_SERVER(dir), dir) < 0)
693 return 0;
694 if (!nfs_verify_change_attribute(dir, dentry->d_time))
695 return 0;
696 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697}
698
Linus Torvalds1da177e2005-04-16 15:20:36 -0700699/*
Trond Myklebust1d6757f2005-06-07 18:37:01 -0400700 * Return the intent data that applies to this particular path component
701 *
702 * Note that the current set of intents only apply to the very last
703 * component of the path.
704 * We check for this using LOOKUP_CONTINUE and LOOKUP_PARENT.
705 */
706static inline unsigned int nfs_lookup_check_intent(struct nameidata *nd, unsigned int mask)
707{
708 if (nd->flags & (LOOKUP_CONTINUE|LOOKUP_PARENT))
709 return 0;
710 return nd->flags & mask;
711}
712
713/*
Trond Myklebusta12802c2007-10-02 19:13:04 -0400714 * Use intent information to check whether or not we're going to do
715 * an O_EXCL create using this path component.
716 */
717static int nfs_is_exclusive_create(struct inode *dir, struct nameidata *nd)
718{
719 if (NFS_PROTO(dir)->version == 2)
720 return 0;
Al Viro35165862008-08-05 03:00:49 -0400721 return nd && nfs_lookup_check_intent(nd, LOOKUP_EXCL);
Trond Myklebusta12802c2007-10-02 19:13:04 -0400722}
723
724/*
Trond Myklebust1d6757f2005-06-07 18:37:01 -0400725 * Inode and filehandle revalidation for lookups.
726 *
727 * We force revalidation in the cases where the VFS sets LOOKUP_REVAL,
728 * or if the intent information indicates that we're about to open this
729 * particular file and the "nocto" mount flag is not set.
730 *
731 */
Linus Torvalds1da177e2005-04-16 15:20:36 -0700732static inline
733int nfs_lookup_verify_inode(struct inode *inode, struct nameidata *nd)
734{
735 struct nfs_server *server = NFS_SERVER(inode);
736
Trond Myklebust4e99a1f2008-03-06 12:34:59 -0500737 if (test_bit(NFS_INO_MOUNTPOINT, &NFS_I(inode)->flags))
738 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739 if (nd != NULL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700740 /* VFS wants an on-the-wire revalidation */
Trond Myklebust1d6757f2005-06-07 18:37:01 -0400741 if (nd->flags & LOOKUP_REVAL)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700742 goto out_force;
743 /* This is an open(2) */
Trond Myklebust1d6757f2005-06-07 18:37:01 -0400744 if (nfs_lookup_check_intent(nd, LOOKUP_OPEN) != 0 &&
Trond Myklebust4e0641a2006-07-05 13:05:13 -0400745 !(server->flags & NFS_MOUNT_NOCTO) &&
746 (S_ISREG(inode->i_mode) ||
747 S_ISDIR(inode->i_mode)))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700748 goto out_force;
Trond Myklebust4f48af42007-10-02 23:13:32 -0400749 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700750 }
751 return nfs_revalidate_inode(server, inode);
752out_force:
753 return __nfs_revalidate_inode(server, inode);
754}
755
756/*
757 * We judge how long we want to trust negative
758 * dentries by looking at the parent inode mtime.
759 *
760 * If parent mtime has changed, we revalidate, else we wait for a
761 * period corresponding to the parent's attribute cache timeout value.
762 */
763static inline
764int nfs_neg_need_reval(struct inode *dir, struct dentry *dentry,
765 struct nameidata *nd)
766{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700767 /* Don't revalidate a negative dentry if we're creating a new file */
Trond Myklebust1d6757f2005-06-07 18:37:01 -0400768 if (nd != NULL && nfs_lookup_check_intent(nd, LOOKUP_CREATE) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700769 return 0;
Trond Myklebust4eec9522008-07-15 17:58:13 -0400770 if (NFS_SERVER(dir)->flags & NFS_MOUNT_LOOKUP_CACHE_NONEG)
771 return 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700772 return !nfs_check_verifier(dir, dentry);
773}
774
775/*
776 * This is called every time the dcache has a lookup hit,
777 * and we should check whether we can really trust that
778 * lookup.
779 *
780 * NOTE! The hit can be a negative hit too, don't assume
781 * we have an inode!
782 *
783 * If the parent directory is seen to have changed, we throw out the
784 * cached dentry and do a new lookup.
785 */
786static int nfs_lookup_revalidate(struct dentry * dentry, struct nameidata *nd)
787{
788 struct inode *dir;
789 struct inode *inode;
790 struct dentry *parent;
Trond Myklebuste1fb4d02010-04-16 16:22:47 -0400791 struct nfs_fh *fhandle = NULL;
792 struct nfs_fattr *fattr = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793 int error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700794
795 parent = dget_parent(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700796 dir = parent->d_inode;
Chuck Lever91d5b472006-03-20 13:44:14 -0500797 nfs_inc_stats(dir, NFSIOS_DENTRYREVALIDATE);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700798 inode = dentry->d_inode;
799
800 if (!inode) {
801 if (nfs_neg_need_reval(dir, dentry, nd))
802 goto out_bad;
803 goto out_valid;
804 }
805
806 if (is_bad_inode(inode)) {
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500807 dfprintk(LOOKUPCACHE, "%s: %s/%s has dud inode\n",
Harvey Harrison3110ff82008-05-02 13:42:44 -0700808 __func__, dentry->d_parent->d_name.name,
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500809 dentry->d_name.name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700810 goto out_bad;
811 }
812
Trond Myklebust15860ab2008-12-23 15:21:54 -0500813 if (nfs_have_delegation(inode, FMODE_READ))
814 goto out_set_verifier;
815
Linus Torvalds1da177e2005-04-16 15:20:36 -0700816 /* Force a full look up iff the parent directory has changed */
Trond Myklebusta12802c2007-10-02 19:13:04 -0400817 if (!nfs_is_exclusive_create(dir, nd) && nfs_check_verifier(dir, dentry)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700818 if (nfs_lookup_verify_inode(inode, nd))
819 goto out_zap_parent;
820 goto out_valid;
821 }
822
823 if (NFS_STALE(inode))
824 goto out_bad;
825
Trond Myklebuste1fb4d02010-04-16 16:22:47 -0400826 error = -ENOMEM;
827 fhandle = nfs_alloc_fhandle();
828 fattr = nfs_alloc_fattr();
829 if (fhandle == NULL || fattr == NULL)
830 goto out_error;
831
832 error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, fhandle, fattr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700833 if (error)
834 goto out_bad;
Trond Myklebuste1fb4d02010-04-16 16:22:47 -0400835 if (nfs_compare_fh(NFS_FH(inode), fhandle))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700836 goto out_bad;
Trond Myklebuste1fb4d02010-04-16 16:22:47 -0400837 if ((error = nfs_refresh_inode(inode, fattr)) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700838 goto out_bad;
839
Trond Myklebuste1fb4d02010-04-16 16:22:47 -0400840 nfs_free_fattr(fattr);
841 nfs_free_fhandle(fhandle);
Trond Myklebust15860ab2008-12-23 15:21:54 -0500842out_set_verifier:
Trond Myklebustcf8ba452007-10-01 13:46:53 -0400843 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700844 out_valid:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700845 dput(parent);
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500846 dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is valid\n",
Harvey Harrison3110ff82008-05-02 13:42:44 -0700847 __func__, dentry->d_parent->d_name.name,
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500848 dentry->d_name.name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700849 return 1;
850out_zap_parent:
851 nfs_zap_caches(dir);
852 out_bad:
Trond Myklebusta1643a92007-09-29 17:25:43 -0400853 nfs_mark_for_revalidate(dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700854 if (inode && S_ISDIR(inode->i_mode)) {
855 /* Purge readdir caches. */
856 nfs_zap_caches(inode);
857 /* If we have submounts, don't unhash ! */
858 if (have_submounts(dentry))
859 goto out_valid;
Al Virod9e80b72010-04-29 03:10:43 +0100860 if (dentry->d_flags & DCACHE_DISCONNECTED)
861 goto out_valid;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700862 shrink_dcache_parent(dentry);
863 }
864 d_drop(dentry);
Trond Myklebuste1fb4d02010-04-16 16:22:47 -0400865 nfs_free_fattr(fattr);
866 nfs_free_fhandle(fhandle);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700867 dput(parent);
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500868 dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) is invalid\n",
Harvey Harrison3110ff82008-05-02 13:42:44 -0700869 __func__, dentry->d_parent->d_name.name,
Chuck Lever1e7cb3d2006-03-20 13:44:24 -0500870 dentry->d_name.name);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700871 return 0;
Trond Myklebuste1fb4d02010-04-16 16:22:47 -0400872out_error:
873 nfs_free_fattr(fattr);
874 nfs_free_fhandle(fhandle);
875 dput(parent);
876 dfprintk(LOOKUPCACHE, "NFS: %s(%s/%s) lookup returned error %d\n",
877 __func__, dentry->d_parent->d_name.name,
878 dentry->d_name.name, error);
879 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880}
881
882/*
883 * This is called from dput() when d_count is going to 0.
884 */
885static int nfs_dentry_delete(struct dentry *dentry)
886{
887 dfprintk(VFS, "NFS: dentry_delete(%s/%s, %x)\n",
888 dentry->d_parent->d_name.name, dentry->d_name.name,
889 dentry->d_flags);
890
Trond Myklebust77f11192008-01-28 19:43:19 -0500891 /* Unhash any dentry with a stale inode */
892 if (dentry->d_inode != NULL && NFS_STALE(dentry->d_inode))
893 return 1;
894
Linus Torvalds1da177e2005-04-16 15:20:36 -0700895 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
896 /* Unhash it, so that ->d_iput() would be called */
897 return 1;
898 }
899 if (!(dentry->d_sb->s_flags & MS_ACTIVE)) {
900 /* Unhash it, so that ancestors of killed async unlink
901 * files will be cleaned up during umount */
902 return 1;
903 }
904 return 0;
905
906}
907
Trond Myklebust1b83d702008-06-11 15:44:04 -0400908static void nfs_drop_nlink(struct inode *inode)
909{
910 spin_lock(&inode->i_lock);
911 if (inode->i_nlink > 0)
912 drop_nlink(inode);
913 spin_unlock(&inode->i_lock);
914}
915
Linus Torvalds1da177e2005-04-16 15:20:36 -0700916/*
917 * Called when the dentry loses inode.
918 * We use it to clean up silly-renamed files.
919 */
920static void nfs_dentry_iput(struct dentry *dentry, struct inode *inode)
921{
Neil Brown83672d32007-02-26 12:48:25 +1100922 if (S_ISDIR(inode->i_mode))
923 /* drop any readdir cache as it could easily be old */
924 NFS_I(inode)->cache_validity |= NFS_INO_INVALID_DATA;
925
Linus Torvalds1da177e2005-04-16 15:20:36 -0700926 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700927 drop_nlink(inode);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -0400928 nfs_complete_unlink(dentry, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700929 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700930 iput(inode);
931}
932
Al Virof786aa92009-02-20 05:51:22 +0000933const struct dentry_operations nfs_dentry_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700934 .d_revalidate = nfs_lookup_revalidate,
935 .d_delete = nfs_dentry_delete,
936 .d_iput = nfs_dentry_iput,
937};
938
Linus Torvalds1da177e2005-04-16 15:20:36 -0700939static struct dentry *nfs_lookup(struct inode *dir, struct dentry * dentry, struct nameidata *nd)
940{
941 struct dentry *res;
Trond Myklebust565277f2007-10-15 18:17:53 -0400942 struct dentry *parent;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700943 struct inode *inode = NULL;
Trond Myklebuste1fb4d02010-04-16 16:22:47 -0400944 struct nfs_fh *fhandle = NULL;
945 struct nfs_fattr *fattr = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700946 int error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947
948 dfprintk(VFS, "NFS: lookup(%s/%s)\n",
949 dentry->d_parent->d_name.name, dentry->d_name.name);
Chuck Lever91d5b472006-03-20 13:44:14 -0500950 nfs_inc_stats(dir, NFSIOS_VFSLOOKUP);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700951
952 res = ERR_PTR(-ENAMETOOLONG);
953 if (dentry->d_name.len > NFS_SERVER(dir)->namelen)
954 goto out;
955
Linus Torvalds1da177e2005-04-16 15:20:36 -0700956 dentry->d_op = NFS_PROTO(dir)->dentry_ops;
957
Trond Myklebustfd684072006-09-05 12:27:44 -0400958 /*
959 * If we're doing an exclusive create, optimize away the lookup
960 * but don't hash the dentry.
961 */
962 if (nfs_is_exclusive_create(dir, nd)) {
963 d_instantiate(dentry, NULL);
964 res = NULL;
Trond Myklebustfc0f6842008-06-11 15:44:20 -0400965 goto out;
Trond Myklebustfd684072006-09-05 12:27:44 -0400966 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700967
Trond Myklebuste1fb4d02010-04-16 16:22:47 -0400968 res = ERR_PTR(-ENOMEM);
969 fhandle = nfs_alloc_fhandle();
970 fattr = nfs_alloc_fattr();
971 if (fhandle == NULL || fattr == NULL)
972 goto out;
973
Trond Myklebust565277f2007-10-15 18:17:53 -0400974 parent = dentry->d_parent;
975 /* Protect against concurrent sillydeletes */
976 nfs_block_sillyrename(parent);
Trond Myklebuste1fb4d02010-04-16 16:22:47 -0400977 error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, fhandle, fattr);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700978 if (error == -ENOENT)
979 goto no_entry;
980 if (error < 0) {
981 res = ERR_PTR(error);
Trond Myklebust565277f2007-10-15 18:17:53 -0400982 goto out_unblock_sillyrename;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700983 }
Trond Myklebuste1fb4d02010-04-16 16:22:47 -0400984 inode = nfs_fhget(dentry->d_sb, fhandle, fattr);
Trond Myklebust03f28e32006-03-20 13:44:48 -0500985 res = (struct dentry *)inode;
986 if (IS_ERR(res))
Trond Myklebust565277f2007-10-15 18:17:53 -0400987 goto out_unblock_sillyrename;
David Howells54ceac42006-08-22 20:06:13 -0400988
Linus Torvalds1da177e2005-04-16 15:20:36 -0700989no_entry:
David Howells54ceac42006-08-22 20:06:13 -0400990 res = d_materialise_unique(dentry, inode);
Trond Myklebust9eaef272006-10-21 10:24:20 -0700991 if (res != NULL) {
992 if (IS_ERR(res))
Trond Myklebust565277f2007-10-15 18:17:53 -0400993 goto out_unblock_sillyrename;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700994 dentry = res;
Trond Myklebust9eaef272006-10-21 10:24:20 -0700995 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700996 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
Trond Myklebust565277f2007-10-15 18:17:53 -0400997out_unblock_sillyrename:
998 nfs_unblock_sillyrename(parent);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700999out:
Trond Myklebuste1fb4d02010-04-16 16:22:47 -04001000 nfs_free_fattr(fattr);
1001 nfs_free_fhandle(fhandle);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001002 return res;
1003}
1004
1005#ifdef CONFIG_NFS_V4
1006static int nfs_open_revalidate(struct dentry *, struct nameidata *);
1007
Al Virof786aa92009-02-20 05:51:22 +00001008const struct dentry_operations nfs4_dentry_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001009 .d_revalidate = nfs_open_revalidate,
1010 .d_delete = nfs_dentry_delete,
1011 .d_iput = nfs_dentry_iput,
1012};
1013
Trond Myklebust1d6757f2005-06-07 18:37:01 -04001014/*
1015 * Use intent information to determine whether we need to substitute
1016 * the NFSv4-style stateful OPEN for the LOOKUP call
1017 */
Trond Myklebust5584c302008-12-23 15:21:54 -05001018static int is_atomic_open(struct nameidata *nd)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001019{
Trond Myklebust1d6757f2005-06-07 18:37:01 -04001020 if (nd == NULL || nfs_lookup_check_intent(nd, LOOKUP_OPEN) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001021 return 0;
1022 /* NFS does not (yet) have a stateful open for directories */
1023 if (nd->flags & LOOKUP_DIRECTORY)
1024 return 0;
1025 /* Are we trying to write to a read only partition? */
Dave Hansen2c463e92008-02-15 14:37:56 -08001026 if (__mnt_is_readonly(nd->path.mnt) &&
1027 (nd->intent.open.flags & (O_CREAT|O_TRUNC|FMODE_WRITE)))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001028 return 0;
1029 return 1;
1030}
1031
1032static struct dentry *nfs_atomic_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
1033{
1034 struct dentry *res = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001035 int error;
1036
Chuck Lever1e7cb3d2006-03-20 13:44:24 -05001037 dfprintk(VFS, "NFS: atomic_lookup(%s/%ld), %s\n",
1038 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
1039
Linus Torvalds1da177e2005-04-16 15:20:36 -07001040 /* Check that we are indeed trying to open this file */
Trond Myklebust5584c302008-12-23 15:21:54 -05001041 if (!is_atomic_open(nd))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001042 goto no_open;
1043
1044 if (dentry->d_name.len > NFS_SERVER(dir)->namelen) {
1045 res = ERR_PTR(-ENAMETOOLONG);
1046 goto out;
1047 }
1048 dentry->d_op = NFS_PROTO(dir)->dentry_ops;
1049
Trond Myklebustd4d9cdc2007-10-02 18:38:53 -04001050 /* Let vfs_create() deal with O_EXCL. Instantiate, but don't hash
1051 * the dentry. */
Al Viro35165862008-08-05 03:00:49 -04001052 if (nd->flags & LOOKUP_EXCL) {
Trond Myklebustd4d9cdc2007-10-02 18:38:53 -04001053 d_instantiate(dentry, NULL);
Trond Myklebust02a913a2005-10-18 14:20:17 -07001054 goto out;
1055 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001056
1057 /* Open the file on the server */
Trond Myklebust60ccd4e2007-09-29 17:48:19 -04001058 res = nfs4_atomic_open(dir, dentry, nd);
Trond Myklebust02a913a2005-10-18 14:20:17 -07001059 if (IS_ERR(res)) {
1060 error = PTR_ERR(res);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001061 switch (error) {
1062 /* Make a negative dentry */
1063 case -ENOENT:
Trond Myklebust02a913a2005-10-18 14:20:17 -07001064 res = NULL;
1065 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001066 /* This turned out not to be a regular file */
Trond Myklebust80e60632010-03-25 13:51:05 -04001067 case -EISDIR:
Trond Myklebust6f926b52005-10-18 14:20:18 -07001068 case -ENOTDIR:
1069 goto no_open;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001070 case -ELOOP:
1071 if (!(nd->intent.open.flags & O_NOFOLLOW))
1072 goto no_open;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001073 /* case -EINVAL: */
1074 default:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001075 goto out;
1076 }
Trond Myklebust02a913a2005-10-18 14:20:17 -07001077 } else if (res != NULL)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001078 dentry = res;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001079out:
1080 return res;
1081no_open:
1082 return nfs_lookup(dir, dentry, nd);
1083}
1084
1085static int nfs_open_revalidate(struct dentry *dentry, struct nameidata *nd)
1086{
1087 struct dentry *parent = NULL;
1088 struct inode *inode = dentry->d_inode;
1089 struct inode *dir;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001090 int openflags, ret = 0;
1091
Trond Myklebust1f063d22010-04-22 15:35:55 -04001092 if (!is_atomic_open(nd) || d_mountpoint(dentry))
Trond Myklebust5584c302008-12-23 15:21:54 -05001093 goto no_open;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001094 parent = dget_parent(dentry);
1095 dir = parent->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001096 /* We can't create new files in nfs_open_revalidate(), so we
1097 * optimize away revalidation of negative dentries.
1098 */
Trond Myklebust216d5d02007-10-01 20:10:12 -04001099 if (inode == NULL) {
1100 if (!nfs_neg_need_reval(dir, dentry, nd))
1101 ret = 1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001102 goto out;
Trond Myklebust216d5d02007-10-01 20:10:12 -04001103 }
1104
Linus Torvalds1da177e2005-04-16 15:20:36 -07001105 /* NFS only supports OPEN on regular files */
1106 if (!S_ISREG(inode->i_mode))
Trond Myklebust5584c302008-12-23 15:21:54 -05001107 goto no_open_dput;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001108 openflags = nd->intent.open.flags;
1109 /* We cannot do exclusive creation on a positive dentry */
1110 if ((openflags & (O_CREAT|O_EXCL)) == (O_CREAT|O_EXCL))
Trond Myklebust5584c302008-12-23 15:21:54 -05001111 goto no_open_dput;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001112 /* We can't create new files, or truncate existing ones here */
Trond Myklebust0a377cf2010-08-18 09:25:42 -04001113 openflags &= ~(O_CREAT|O_EXCL|O_TRUNC);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001114
1115 /*
Jes Sorensen1b1dcc12006-01-09 15:59:24 -08001116 * Note: we're not holding inode->i_mutex and so may be racing with
Linus Torvalds1da177e2005-04-16 15:20:36 -07001117 * operations that change the directory. We therefore save the
1118 * change attribute *before* we do the RPC call.
1119 */
Trond Myklebust02a913a2005-10-18 14:20:17 -07001120 ret = nfs4_open_revalidate(dir, dentry, openflags, nd);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001121out:
1122 dput(parent);
1123 if (!ret)
1124 d_drop(dentry);
1125 return ret;
Trond Myklebust5584c302008-12-23 15:21:54 -05001126no_open_dput:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001127 dput(parent);
Trond Myklebust5584c302008-12-23 15:21:54 -05001128no_open:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001129 return nfs_lookup_revalidate(dentry, nd);
1130}
1131#endif /* CONFIG_NFSV4 */
1132
1133static struct dentry *nfs_readdir_lookup(nfs_readdir_descriptor_t *desc)
1134{
Josef "Jeff" Sipek01cce932006-12-08 02:36:40 -08001135 struct dentry *parent = desc->file->f_path.dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001136 struct inode *dir = parent->d_inode;
1137 struct nfs_entry *entry = desc->entry;
1138 struct dentry *dentry, *alias;
1139 struct qstr name = {
1140 .name = entry->name,
1141 .len = entry->len,
1142 };
1143 struct inode *inode;
Trond Myklebust57fa76f2007-09-30 18:01:13 -04001144 unsigned long verf = nfs_save_change_attribute(dir);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001145
1146 switch (name.len) {
1147 case 2:
1148 if (name.name[0] == '.' && name.name[1] == '.')
1149 return dget_parent(parent);
1150 break;
1151 case 1:
1152 if (name.name[0] == '.')
1153 return dget(parent);
1154 }
Trond Myklebust57fa76f2007-09-30 18:01:13 -04001155
1156 spin_lock(&dir->i_lock);
1157 if (NFS_I(dir)->cache_validity & NFS_INO_INVALID_DATA) {
1158 spin_unlock(&dir->i_lock);
1159 return NULL;
1160 }
1161 spin_unlock(&dir->i_lock);
1162
Linus Torvalds1da177e2005-04-16 15:20:36 -07001163 name.hash = full_name_hash(name.name, name.len);
1164 dentry = d_lookup(parent, &name);
Trond Myklebustdf1d5d22007-01-15 13:56:29 -05001165 if (dentry != NULL) {
Trond Myklebustef75c792007-01-16 10:09:44 -05001166 /* Is this a positive dentry that matches the readdir info? */
1167 if (dentry->d_inode != NULL &&
1168 (NFS_FILEID(dentry->d_inode) == entry->ino ||
1169 d_mountpoint(dentry))) {
1170 if (!desc->plus || entry->fh->size == 0)
1171 return dentry;
1172 if (nfs_compare_fh(NFS_FH(dentry->d_inode),
1173 entry->fh) == 0)
1174 goto out_renew;
1175 }
Trond Myklebustdf1d5d22007-01-15 13:56:29 -05001176 /* No, so d_drop to allow one to be created */
1177 d_drop(dentry);
1178 dput(dentry);
1179 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001180 if (!desc->plus || !(entry->fattr->valid & NFS_ATTR_FATTR))
1181 return NULL;
Trond Myklebust54af3bb2007-09-28 12:27:41 -04001182 if (name.len > NFS_SERVER(dir)->namelen)
1183 return NULL;
Jes Sorensen1b1dcc12006-01-09 15:59:24 -08001184 /* Note: caller is already holding the dir->i_mutex! */
Linus Torvalds1da177e2005-04-16 15:20:36 -07001185 dentry = d_alloc(parent, &name);
1186 if (dentry == NULL)
1187 return NULL;
1188 dentry->d_op = NFS_PROTO(dir)->dentry_ops;
1189 inode = nfs_fhget(dentry->d_sb, entry->fh, entry->fattr);
Trond Myklebust03f28e32006-03-20 13:44:48 -05001190 if (IS_ERR(inode)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001191 dput(dentry);
1192 return NULL;
1193 }
David Howells54ceac42006-08-22 20:06:13 -04001194
1195 alias = d_materialise_unique(dentry, inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001196 if (alias != NULL) {
1197 dput(dentry);
Trond Myklebust9eaef272006-10-21 10:24:20 -07001198 if (IS_ERR(alias))
1199 return NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001200 dentry = alias;
1201 }
David Howells54ceac42006-08-22 20:06:13 -04001202
Trond Myklebustc79ba782007-01-31 08:16:24 -05001203out_renew:
Trond Myklebust57fa76f2007-09-30 18:01:13 -04001204 nfs_set_verifier(dentry, verf);
Trond Myklebustc79ba782007-01-31 08:16:24 -05001205 return dentry;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001206}
1207
1208/*
1209 * Code common to create, mkdir, and mknod.
1210 */
1211int nfs_instantiate(struct dentry *dentry, struct nfs_fh *fhandle,
1212 struct nfs_fattr *fattr)
1213{
Trond Myklebustfab728e2007-09-29 17:41:33 -04001214 struct dentry *parent = dget_parent(dentry);
1215 struct inode *dir = parent->d_inode;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001216 struct inode *inode;
1217 int error = -EACCES;
1218
Trond Myklebustfab728e2007-09-29 17:41:33 -04001219 d_drop(dentry);
1220
Linus Torvalds1da177e2005-04-16 15:20:36 -07001221 /* We may have been initialized further down */
1222 if (dentry->d_inode)
Trond Myklebustfab728e2007-09-29 17:41:33 -04001223 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001224 if (fhandle->size == 0) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001225 error = NFS_PROTO(dir)->lookup(dir, &dentry->d_name, fhandle, fattr);
1226 if (error)
Trond Myklebustfab728e2007-09-29 17:41:33 -04001227 goto out_error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001228 }
Trond Myklebust5724ab32007-10-01 21:51:38 -04001229 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001230 if (!(fattr->valid & NFS_ATTR_FATTR)) {
1231 struct nfs_server *server = NFS_SB(dentry->d_sb);
David Howells8fa5c002006-08-22 20:06:12 -04001232 error = server->nfs_client->rpc_ops->getattr(server, fhandle, fattr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001233 if (error < 0)
Trond Myklebustfab728e2007-09-29 17:41:33 -04001234 goto out_error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001235 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001236 inode = nfs_fhget(dentry->d_sb, fhandle, fattr);
Trond Myklebust03f28e32006-03-20 13:44:48 -05001237 error = PTR_ERR(inode);
1238 if (IS_ERR(inode))
Trond Myklebustfab728e2007-09-29 17:41:33 -04001239 goto out_error;
1240 d_add(dentry, inode);
1241out:
1242 dput(parent);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001243 return 0;
Trond Myklebustfab728e2007-09-29 17:41:33 -04001244out_error:
1245 nfs_mark_for_revalidate(dir);
1246 dput(parent);
1247 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001248}
1249
1250/*
1251 * Following a failed create operation, we drop the dentry rather
1252 * than retain a negative dentry. This avoids a problem in the event
1253 * that the operation succeeded on the server, but an error in the
1254 * reply path made it appear to have failed.
1255 */
1256static int nfs_create(struct inode *dir, struct dentry *dentry, int mode,
1257 struct nameidata *nd)
1258{
1259 struct iattr attr;
1260 int error;
1261 int open_flags = 0;
1262
Chuck Lever1e7cb3d2006-03-20 13:44:24 -05001263 dfprintk(VFS, "NFS: create(%s/%ld), %s\n",
1264 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001265
1266 attr.ia_mode = mode;
1267 attr.ia_valid = ATTR_MODE;
1268
Trond Myklebustad389da2007-06-05 12:30:00 -04001269 if ((nd->flags & LOOKUP_CREATE) != 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001270 open_flags = nd->intent.open.flags;
1271
Trond Myklebust02a913a2005-10-18 14:20:17 -07001272 error = NFS_PROTO(dir)->create(dir, dentry, &attr, open_flags, nd);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001273 if (error != 0)
1274 goto out_err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001275 return 0;
1276out_err:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001277 d_drop(dentry);
1278 return error;
1279}
1280
1281/*
1282 * See comments for nfs_proc_create regarding failed operations.
1283 */
1284static int
1285nfs_mknod(struct inode *dir, struct dentry *dentry, int mode, dev_t rdev)
1286{
1287 struct iattr attr;
1288 int status;
1289
Chuck Lever1e7cb3d2006-03-20 13:44:24 -05001290 dfprintk(VFS, "NFS: mknod(%s/%ld), %s\n",
1291 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001292
1293 if (!new_valid_dev(rdev))
1294 return -EINVAL;
1295
1296 attr.ia_mode = mode;
1297 attr.ia_valid = ATTR_MODE;
1298
Linus Torvalds1da177e2005-04-16 15:20:36 -07001299 status = NFS_PROTO(dir)->mknod(dir, dentry, &attr, rdev);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001300 if (status != 0)
1301 goto out_err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001302 return 0;
1303out_err:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001304 d_drop(dentry);
1305 return status;
1306}
1307
1308/*
1309 * See comments for nfs_proc_create regarding failed operations.
1310 */
1311static int nfs_mkdir(struct inode *dir, struct dentry *dentry, int mode)
1312{
1313 struct iattr attr;
1314 int error;
1315
Chuck Lever1e7cb3d2006-03-20 13:44:24 -05001316 dfprintk(VFS, "NFS: mkdir(%s/%ld), %s\n",
1317 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001318
1319 attr.ia_valid = ATTR_MODE;
1320 attr.ia_mode = mode | S_IFDIR;
1321
Linus Torvalds1da177e2005-04-16 15:20:36 -07001322 error = NFS_PROTO(dir)->mkdir(dir, dentry, &attr);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001323 if (error != 0)
1324 goto out_err;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001325 return 0;
1326out_err:
1327 d_drop(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001328 return error;
1329}
1330
Trond Myklebustd45b9d82008-01-28 19:43:18 -05001331static void nfs_dentry_handle_enoent(struct dentry *dentry)
1332{
1333 if (dentry->d_inode != NULL && !d_unhashed(dentry))
1334 d_delete(dentry);
1335}
1336
Linus Torvalds1da177e2005-04-16 15:20:36 -07001337static int nfs_rmdir(struct inode *dir, struct dentry *dentry)
1338{
1339 int error;
1340
Chuck Lever1e7cb3d2006-03-20 13:44:24 -05001341 dfprintk(VFS, "NFS: rmdir(%s/%ld), %s\n",
1342 dir->i_sb->s_id, dir->i_ino, dentry->d_name.name);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001343
Linus Torvalds1da177e2005-04-16 15:20:36 -07001344 error = NFS_PROTO(dir)->rmdir(dir, &dentry->d_name);
1345 /* Ensure the VFS deletes this inode */
1346 if (error == 0 && dentry->d_inode != NULL)
Dave Hansence71ec32006-09-30 23:29:06 -07001347 clear_nlink(dentry->d_inode);
Trond Myklebustd45b9d82008-01-28 19:43:18 -05001348 else if (error == -ENOENT)
1349 nfs_dentry_handle_enoent(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001350
1351 return error;
1352}
1353
1354static int nfs_sillyrename(struct inode *dir, struct dentry *dentry)
1355{
1356 static unsigned int sillycounter;
Peter Staubach4e769b92007-08-03 15:07:10 -04001357 const int fileidsize = sizeof(NFS_FILEID(dentry->d_inode))*2;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001358 const int countersize = sizeof(sillycounter)*2;
Peter Staubach4e769b92007-08-03 15:07:10 -04001359 const int slen = sizeof(".nfs")+fileidsize+countersize-1;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001360 char silly[slen+1];
1361 struct qstr qsilly;
1362 struct dentry *sdentry;
1363 int error = -EIO;
1364
1365 dfprintk(VFS, "NFS: silly-rename(%s/%s, ct=%d)\n",
1366 dentry->d_parent->d_name.name, dentry->d_name.name,
1367 atomic_read(&dentry->d_count));
Chuck Lever91d5b472006-03-20 13:44:14 -05001368 nfs_inc_stats(dir, NFSIOS_SILLYRENAME);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001369
Linus Torvalds1da177e2005-04-16 15:20:36 -07001370 /*
1371 * We don't allow a dentry to be silly-renamed twice.
1372 */
1373 error = -EBUSY;
1374 if (dentry->d_flags & DCACHE_NFSFS_RENAMED)
1375 goto out;
1376
Peter Staubach4e769b92007-08-03 15:07:10 -04001377 sprintf(silly, ".nfs%*.*Lx",
1378 fileidsize, fileidsize,
1379 (unsigned long long)NFS_FILEID(dentry->d_inode));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001380
Trond Myklebust34ea8182005-11-04 15:35:02 -05001381 /* Return delegation in anticipation of the rename */
1382 nfs_inode_return_delegation(dentry->d_inode);
1383
Linus Torvalds1da177e2005-04-16 15:20:36 -07001384 sdentry = NULL;
1385 do {
1386 char *suffix = silly + slen - countersize;
1387
1388 dput(sdentry);
1389 sillycounter++;
1390 sprintf(suffix, "%*.*x", countersize, countersize, sillycounter);
1391
Chuck Lever1e7cb3d2006-03-20 13:44:24 -05001392 dfprintk(VFS, "NFS: trying to rename %s to %s\n",
1393 dentry->d_name.name, silly);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001394
1395 sdentry = lookup_one_len(silly, dentry->d_parent, slen);
1396 /*
1397 * N.B. Better to return EBUSY here ... it could be
1398 * dangerous to delete the file while it's in use.
1399 */
1400 if (IS_ERR(sdentry))
1401 goto out;
1402 } while(sdentry->d_inode != NULL); /* need negative lookup */
1403
1404 qsilly.name = silly;
1405 qsilly.len = strlen(silly);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001406 if (dentry->d_inode) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001407 error = NFS_PROTO(dir)->rename(dir, &dentry->d_name,
1408 dir, &qsilly);
Trond Myklebust5ba7cc42005-12-03 15:20:17 -05001409 nfs_mark_for_revalidate(dentry->d_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001410 } else
1411 error = NFS_PROTO(dir)->rename(dir, &dentry->d_name,
1412 dir, &qsilly);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001413 if (!error) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001414 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1415 d_move(dentry, sdentry);
Trond Myklebuste4eff1a2007-07-14 15:39:58 -04001416 error = nfs_async_unlink(dir, dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001417 /* If we return 0 we don't unlink */
1418 }
1419 dput(sdentry);
1420out:
1421 return error;
1422}
1423
1424/*
1425 * Remove a file after making sure there are no pending writes,
1426 * and after checking that the file has only one user.
1427 *
1428 * We invalidate the attribute cache and free the inode prior to the operation
1429 * to avoid possible races if the server reuses the inode.
1430 */
1431static int nfs_safe_remove(struct dentry *dentry)
1432{
1433 struct inode *dir = dentry->d_parent->d_inode;
1434 struct inode *inode = dentry->d_inode;
1435 int error = -EBUSY;
1436
1437 dfprintk(VFS, "NFS: safe_remove(%s/%s)\n",
1438 dentry->d_parent->d_name.name, dentry->d_name.name);
1439
1440 /* If the dentry was sillyrenamed, we simply call d_delete() */
1441 if (dentry->d_flags & DCACHE_NFSFS_RENAMED) {
1442 error = 0;
1443 goto out;
1444 }
1445
Linus Torvalds1da177e2005-04-16 15:20:36 -07001446 if (inode != NULL) {
Trond Myklebustcae7a072005-10-18 14:20:19 -07001447 nfs_inode_return_delegation(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001448 error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
1449 /* The VFS may want to delete this inode */
1450 if (error == 0)
Trond Myklebust1b83d702008-06-11 15:44:04 -04001451 nfs_drop_nlink(inode);
Trond Myklebust5ba7cc42005-12-03 15:20:17 -05001452 nfs_mark_for_revalidate(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001453 } else
1454 error = NFS_PROTO(dir)->remove(dir, &dentry->d_name);
Trond Myklebustd45b9d82008-01-28 19:43:18 -05001455 if (error == -ENOENT)
1456 nfs_dentry_handle_enoent(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001457out:
1458 return error;
1459}
1460
1461/* We do silly rename. In case sillyrename() returns -EBUSY, the inode
1462 * belongs to an active ".nfs..." file and we return -EBUSY.
1463 *
1464 * If sillyrename() returns 0, we do nothing, otherwise we unlink.
1465 */
1466static int nfs_unlink(struct inode *dir, struct dentry *dentry)
1467{
1468 int error;
1469 int need_rehash = 0;
1470
1471 dfprintk(VFS, "NFS: unlink(%s/%ld, %s)\n", dir->i_sb->s_id,
1472 dir->i_ino, dentry->d_name.name);
1473
Linus Torvalds1da177e2005-04-16 15:20:36 -07001474 spin_lock(&dcache_lock);
1475 spin_lock(&dentry->d_lock);
1476 if (atomic_read(&dentry->d_count) > 1) {
1477 spin_unlock(&dentry->d_lock);
1478 spin_unlock(&dcache_lock);
Trond Myklebustccfeb502007-01-13 02:28:12 -05001479 /* Start asynchronous writeout of the inode */
1480 write_inode_now(dentry->d_inode, 0);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001481 error = nfs_sillyrename(dir, dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001482 return error;
1483 }
1484 if (!d_unhashed(dentry)) {
1485 __d_drop(dentry);
1486 need_rehash = 1;
1487 }
1488 spin_unlock(&dentry->d_lock);
1489 spin_unlock(&dcache_lock);
1490 error = nfs_safe_remove(dentry);
Trond Myklebustd45b9d82008-01-28 19:43:18 -05001491 if (!error || error == -ENOENT) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001492 nfs_set_verifier(dentry, nfs_save_change_attribute(dir));
1493 } else if (need_rehash)
1494 d_rehash(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001495 return error;
1496}
1497
Chuck Lever873101b2006-08-22 20:06:23 -04001498/*
1499 * To create a symbolic link, most file systems instantiate a new inode,
1500 * add a page to it containing the path, then write it out to the disk
1501 * using prepare_write/commit_write.
1502 *
1503 * Unfortunately the NFS client can't create the in-core inode first
1504 * because it needs a file handle to create an in-core inode (see
1505 * fs/nfs/inode.c:nfs_fhget). We only have a file handle *after* the
1506 * symlink request has completed on the server.
1507 *
1508 * So instead we allocate a raw page, copy the symname into it, then do
1509 * the SYMLINK request with the page as the buffer. If it succeeds, we
1510 * now have a new file handle and can instantiate an in-core NFS inode
1511 * and move the raw page into its mapping.
1512 */
1513static int nfs_symlink(struct inode *dir, struct dentry *dentry, const char *symname)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001514{
Chuck Lever873101b2006-08-22 20:06:23 -04001515 struct pagevec lru_pvec;
1516 struct page *page;
1517 char *kaddr;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001518 struct iattr attr;
Chuck Lever873101b2006-08-22 20:06:23 -04001519 unsigned int pathlen = strlen(symname);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001520 int error;
1521
1522 dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s)\n", dir->i_sb->s_id,
1523 dir->i_ino, dentry->d_name.name, symname);
1524
Chuck Lever873101b2006-08-22 20:06:23 -04001525 if (pathlen > PAGE_SIZE)
1526 return -ENAMETOOLONG;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001527
Chuck Lever873101b2006-08-22 20:06:23 -04001528 attr.ia_mode = S_IFLNK | S_IRWXUGO;
1529 attr.ia_valid = ATTR_MODE;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001530
Jeff Layton83d93f22007-06-07 09:58:08 -04001531 page = alloc_page(GFP_HIGHUSER);
Trond Myklebust76566992008-06-11 15:44:22 -04001532 if (!page)
Chuck Lever873101b2006-08-22 20:06:23 -04001533 return -ENOMEM;
Chuck Lever873101b2006-08-22 20:06:23 -04001534
1535 kaddr = kmap_atomic(page, KM_USER0);
1536 memcpy(kaddr, symname, pathlen);
1537 if (pathlen < PAGE_SIZE)
1538 memset(kaddr + pathlen, 0, PAGE_SIZE - pathlen);
1539 kunmap_atomic(kaddr, KM_USER0);
1540
Chuck Lever94a6d752006-08-22 20:06:23 -04001541 error = NFS_PROTO(dir)->symlink(dir, dentry, page, pathlen, &attr);
Chuck Lever873101b2006-08-22 20:06:23 -04001542 if (error != 0) {
1543 dfprintk(VFS, "NFS: symlink(%s/%ld, %s, %s) error %d\n",
1544 dir->i_sb->s_id, dir->i_ino,
1545 dentry->d_name.name, symname, error);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001546 d_drop(dentry);
Chuck Lever873101b2006-08-22 20:06:23 -04001547 __free_page(page);
Chuck Lever873101b2006-08-22 20:06:23 -04001548 return error;
1549 }
1550
1551 /*
1552 * No big deal if we can't add this page to the page cache here.
1553 * READLINK will get the missing page from the server if needed.
1554 */
1555 pagevec_init(&lru_pvec, 0);
1556 if (!add_to_page_cache(page, dentry->d_inode->i_mapping, 0,
1557 GFP_KERNEL)) {
Chuck Lever39cf8a12006-10-19 23:28:41 -07001558 pagevec_add(&lru_pvec, page);
Rik van Riel4f98a2f2008-10-18 20:26:32 -07001559 pagevec_lru_add_file(&lru_pvec);
Chuck Lever873101b2006-08-22 20:06:23 -04001560 SetPageUptodate(page);
1561 unlock_page(page);
1562 } else
1563 __free_page(page);
1564
Chuck Lever873101b2006-08-22 20:06:23 -04001565 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001566}
1567
1568static int
1569nfs_link(struct dentry *old_dentry, struct inode *dir, struct dentry *dentry)
1570{
1571 struct inode *inode = old_dentry->d_inode;
1572 int error;
1573
1574 dfprintk(VFS, "NFS: link(%s/%s -> %s/%s)\n",
1575 old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
1576 dentry->d_parent->d_name.name, dentry->d_name.name);
1577
Trond Myklebust9a3936a2009-10-26 08:09:46 -04001578 nfs_inode_return_delegation(inode);
1579
Trond Myklebust9697d232007-10-02 21:58:05 -04001580 d_drop(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001581 error = NFS_PROTO(dir)->link(inode, dir, &dentry->d_name);
Trond Myklebustcf809552005-10-27 22:12:42 -04001582 if (error == 0) {
1583 atomic_inc(&inode->i_count);
Trond Myklebust9697d232007-10-02 21:58:05 -04001584 d_add(dentry, inode);
Trond Myklebustcf809552005-10-27 22:12:42 -04001585 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001586 return error;
1587}
1588
1589/*
1590 * RENAME
1591 * FIXME: Some nfsds, like the Linux user space nfsd, may generate a
1592 * different file handle for the same inode after a rename (e.g. when
1593 * moving to a different directory). A fail-safe method to do so would
1594 * be to look up old_dir/old_name, create a link to new_dir/new_name and
1595 * rename the old file using the sillyrename stuff. This way, the original
1596 * file in old_dir will go away when the last process iput()s the inode.
1597 *
1598 * FIXED.
1599 *
1600 * It actually works quite well. One needs to have the possibility for
1601 * at least one ".nfs..." file in each directory the file ever gets
1602 * moved or linked to which happens automagically with the new
1603 * implementation that only depends on the dcache stuff instead of
1604 * using the inode layer
1605 *
1606 * Unfortunately, things are a little more complicated than indicated
1607 * above. For a cross-directory move, we want to make sure we can get
1608 * rid of the old inode after the operation. This means there must be
1609 * no pending writes (if it's a file), and the use count must be 1.
1610 * If these conditions are met, we can drop the dentries before doing
1611 * the rename.
1612 */
1613static int nfs_rename(struct inode *old_dir, struct dentry *old_dentry,
1614 struct inode *new_dir, struct dentry *new_dentry)
1615{
1616 struct inode *old_inode = old_dentry->d_inode;
1617 struct inode *new_inode = new_dentry->d_inode;
1618 struct dentry *dentry = NULL, *rehash = NULL;
1619 int error = -EBUSY;
1620
Linus Torvalds1da177e2005-04-16 15:20:36 -07001621 dfprintk(VFS, "NFS: rename(%s/%s -> %s/%s, ct=%d)\n",
1622 old_dentry->d_parent->d_name.name, old_dentry->d_name.name,
1623 new_dentry->d_parent->d_name.name, new_dentry->d_name.name,
1624 atomic_read(&new_dentry->d_count));
1625
1626 /*
Miklos Szeredi28f79a12009-12-03 15:58:56 -05001627 * For non-directories, check whether the target is busy and if so,
1628 * make a copy of the dentry and then do a silly-rename. If the
1629 * silly-rename succeeds, the copied dentry is hashed and becomes
1630 * the new target.
Linus Torvalds1da177e2005-04-16 15:20:36 -07001631 */
Miklos Szeredi27226102009-12-03 15:58:56 -05001632 if (new_inode && !S_ISDIR(new_inode->i_mode)) {
1633 /*
1634 * To prevent any new references to the target during the
1635 * rename, we unhash the dentry in advance.
1636 */
1637 if (!d_unhashed(new_dentry)) {
1638 d_drop(new_dentry);
1639 rehash = new_dentry;
1640 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001641
Miklos Szeredi27226102009-12-03 15:58:56 -05001642 if (atomic_read(&new_dentry->d_count) > 2) {
1643 int err;
1644
1645 /* copy the target dentry's name */
1646 dentry = d_alloc(new_dentry->d_parent,
1647 &new_dentry->d_name);
1648 if (!dentry)
1649 goto out;
1650
1651 /* silly-rename the existing target ... */
1652 err = nfs_sillyrename(new_dir, new_dentry);
Miklos Szeredi24e93022009-12-03 15:58:56 -05001653 if (err)
Miklos Szeredi27226102009-12-03 15:58:56 -05001654 goto out;
Miklos Szeredi24e93022009-12-03 15:58:56 -05001655
1656 new_dentry = dentry;
OGAWA Hirofumi56335932010-01-06 18:48:26 -05001657 rehash = NULL;
Miklos Szeredi24e93022009-12-03 15:58:56 -05001658 new_inode = NULL;
Miklos Szeredi27226102009-12-03 15:58:56 -05001659 }
Trond Myklebustb1e4adf2009-03-19 15:35:49 -04001660 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001661
Trond Myklebustcae7a072005-10-18 14:20:19 -07001662 nfs_inode_return_delegation(old_inode);
Trond Myklebustb1e4adf2009-03-19 15:35:49 -04001663 if (new_inode != NULL)
Trond Myklebust24174112006-01-03 09:55:33 +01001664 nfs_inode_return_delegation(new_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001665
Linus Torvalds1da177e2005-04-16 15:20:36 -07001666 error = NFS_PROTO(old_dir)->rename(old_dir, &old_dentry->d_name,
1667 new_dir, &new_dentry->d_name);
Trond Myklebust5ba7cc42005-12-03 15:20:17 -05001668 nfs_mark_for_revalidate(old_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001669out:
1670 if (rehash)
1671 d_rehash(rehash);
1672 if (!error) {
Trond Myklebustb1e4adf2009-03-19 15:35:49 -04001673 if (new_inode != NULL)
1674 nfs_drop_nlink(new_inode);
Mark Fasheh349457c2006-09-08 14:22:21 -07001675 d_move(old_dentry, new_dentry);
Chuck Lever8fb559f2007-09-24 15:40:16 -04001676 nfs_set_verifier(new_dentry,
1677 nfs_save_change_attribute(new_dir));
Trond Myklebustd45b9d82008-01-28 19:43:18 -05001678 } else if (error == -ENOENT)
1679 nfs_dentry_handle_enoent(old_dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001680
1681 /* new dentry created? */
1682 if (dentry)
1683 dput(dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001684 return error;
1685}
1686
Trond Myklebustcfcea3e2006-07-25 11:28:18 -04001687static DEFINE_SPINLOCK(nfs_access_lru_lock);
1688static LIST_HEAD(nfs_access_lru_list);
1689static atomic_long_t nfs_access_nr_entries;
1690
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001691static void nfs_access_free_entry(struct nfs_access_entry *entry)
1692{
1693 put_rpccred(entry->cred);
1694 kfree(entry);
Trond Myklebustcfcea3e2006-07-25 11:28:18 -04001695 smp_mb__before_atomic_dec();
1696 atomic_long_dec(&nfs_access_nr_entries);
1697 smp_mb__after_atomic_dec();
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001698}
1699
Trond Myklebust1a81bb82010-05-13 12:51:06 -04001700static void nfs_access_free_list(struct list_head *head)
1701{
1702 struct nfs_access_entry *cache;
1703
1704 while (!list_empty(head)) {
1705 cache = list_entry(head->next, struct nfs_access_entry, lru);
1706 list_del(&cache->lru);
1707 nfs_access_free_entry(cache);
1708 }
1709}
1710
Dave Chinner7f8275d2010-07-19 14:56:17 +10001711int nfs_access_cache_shrinker(struct shrinker *shrink, int nr_to_scan, gfp_t gfp_mask)
Trond Myklebust979df722006-07-25 11:28:19 -04001712{
1713 LIST_HEAD(head);
1714 struct nfs_inode *nfsi;
1715 struct nfs_access_entry *cache;
1716
Trond Myklebust61d5eb22010-05-13 12:51:06 -04001717 if ((gfp_mask & GFP_KERNEL) != GFP_KERNEL)
1718 return (nr_to_scan == 0) ? 0 : -1;
Trond Myklebust9c7e7e22010-05-13 12:51:06 -04001719
Trond Myklebusta50f7952007-06-05 19:23:43 -04001720 spin_lock(&nfs_access_lru_lock);
Trond Myklebust979df722006-07-25 11:28:19 -04001721 list_for_each_entry(nfsi, &nfs_access_lru_list, access_cache_inode_lru) {
1722 struct inode *inode;
1723
1724 if (nr_to_scan-- == 0)
1725 break;
Trond Myklebust9c7e7e22010-05-13 12:51:06 -04001726 inode = &nfsi->vfs_inode;
Trond Myklebust979df722006-07-25 11:28:19 -04001727 spin_lock(&inode->i_lock);
1728 if (list_empty(&nfsi->access_cache_entry_lru))
1729 goto remove_lru_entry;
1730 cache = list_entry(nfsi->access_cache_entry_lru.next,
1731 struct nfs_access_entry, lru);
1732 list_move(&cache->lru, &head);
1733 rb_erase(&cache->rb_node, &nfsi->access_cache);
1734 if (!list_empty(&nfsi->access_cache_entry_lru))
1735 list_move_tail(&nfsi->access_cache_inode_lru,
1736 &nfs_access_lru_list);
1737 else {
1738remove_lru_entry:
1739 list_del_init(&nfsi->access_cache_inode_lru);
Trond Myklebust9c7e7e22010-05-13 12:51:06 -04001740 smp_mb__before_clear_bit();
Trond Myklebust979df722006-07-25 11:28:19 -04001741 clear_bit(NFS_INO_ACL_LRU_SET, &nfsi->flags);
Trond Myklebust9c7e7e22010-05-13 12:51:06 -04001742 smp_mb__after_clear_bit();
Trond Myklebust979df722006-07-25 11:28:19 -04001743 }
Trond Myklebust59844a92010-05-26 08:42:24 -04001744 spin_unlock(&inode->i_lock);
Trond Myklebust979df722006-07-25 11:28:19 -04001745 }
1746 spin_unlock(&nfs_access_lru_lock);
Trond Myklebust1a81bb82010-05-13 12:51:06 -04001747 nfs_access_free_list(&head);
Trond Myklebust979df722006-07-25 11:28:19 -04001748 return (atomic_long_read(&nfs_access_nr_entries) / 100) * sysctl_vfs_cache_pressure;
1749}
1750
Trond Myklebust1a81bb82010-05-13 12:51:06 -04001751static void __nfs_access_zap_cache(struct nfs_inode *nfsi, struct list_head *head)
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001752{
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001753 struct rb_root *root_node = &nfsi->access_cache;
Trond Myklebust1a81bb82010-05-13 12:51:06 -04001754 struct rb_node *n;
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001755 struct nfs_access_entry *entry;
1756
1757 /* Unhook entries from the cache */
1758 while ((n = rb_first(root_node)) != NULL) {
1759 entry = rb_entry(n, struct nfs_access_entry, rb_node);
1760 rb_erase(n, root_node);
Trond Myklebust1a81bb82010-05-13 12:51:06 -04001761 list_move(&entry->lru, head);
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001762 }
1763 nfsi->cache_validity &= ~NFS_INO_INVALID_ACCESS;
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001764}
1765
1766void nfs_access_zap_cache(struct inode *inode)
1767{
Trond Myklebust1a81bb82010-05-13 12:51:06 -04001768 LIST_HEAD(head);
1769
1770 if (test_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags) == 0)
1771 return;
Trond Myklebustcfcea3e2006-07-25 11:28:18 -04001772 /* Remove from global LRU init */
Trond Myklebust1a81bb82010-05-13 12:51:06 -04001773 spin_lock(&nfs_access_lru_lock);
1774 if (test_and_clear_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags))
Trond Myklebustcfcea3e2006-07-25 11:28:18 -04001775 list_del_init(&NFS_I(inode)->access_cache_inode_lru);
Trond Myklebustcfcea3e2006-07-25 11:28:18 -04001776
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001777 spin_lock(&inode->i_lock);
Trond Myklebust1a81bb82010-05-13 12:51:06 -04001778 __nfs_access_zap_cache(NFS_I(inode), &head);
1779 spin_unlock(&inode->i_lock);
1780 spin_unlock(&nfs_access_lru_lock);
1781 nfs_access_free_list(&head);
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001782}
1783
1784static struct nfs_access_entry *nfs_access_search_rbtree(struct inode *inode, struct rpc_cred *cred)
1785{
1786 struct rb_node *n = NFS_I(inode)->access_cache.rb_node;
1787 struct nfs_access_entry *entry;
1788
1789 while (n != NULL) {
1790 entry = rb_entry(n, struct nfs_access_entry, rb_node);
1791
1792 if (cred < entry->cred)
1793 n = n->rb_left;
1794 else if (cred > entry->cred)
1795 n = n->rb_right;
1796 else
1797 return entry;
1798 }
1799 return NULL;
1800}
1801
Trond Myklebustaf22f942007-08-10 17:45:10 -04001802static int nfs_access_get_cached(struct inode *inode, struct rpc_cred *cred, struct nfs_access_entry *res)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001803{
Chuck Lever55296802005-08-18 11:24:09 -07001804 struct nfs_inode *nfsi = NFS_I(inode);
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001805 struct nfs_access_entry *cache;
1806 int err = -ENOENT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001807
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001808 spin_lock(&inode->i_lock);
1809 if (nfsi->cache_validity & NFS_INO_INVALID_ACCESS)
1810 goto out_zap;
1811 cache = nfs_access_search_rbtree(inode, cred);
1812 if (cache == NULL)
1813 goto out;
Trond Myklebustb4d23142010-03-10 15:21:44 -05001814 if (!nfs_have_delegated_attributes(inode) &&
Peter Staubach64672d52008-12-23 15:21:56 -05001815 !time_in_range_open(jiffies, cache->jiffies, cache->jiffies + nfsi->attrtimeo))
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001816 goto out_stale;
1817 res->jiffies = cache->jiffies;
1818 res->cred = cache->cred;
1819 res->mask = cache->mask;
Trond Myklebustcfcea3e2006-07-25 11:28:18 -04001820 list_move_tail(&cache->lru, &nfsi->access_cache_entry_lru);
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001821 err = 0;
1822out:
1823 spin_unlock(&inode->i_lock);
1824 return err;
1825out_stale:
1826 rb_erase(&cache->rb_node, &nfsi->access_cache);
Trond Myklebustcfcea3e2006-07-25 11:28:18 -04001827 list_del(&cache->lru);
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001828 spin_unlock(&inode->i_lock);
1829 nfs_access_free_entry(cache);
1830 return -ENOENT;
1831out_zap:
Trond Myklebust1a81bb82010-05-13 12:51:06 -04001832 spin_unlock(&inode->i_lock);
1833 nfs_access_zap_cache(inode);
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001834 return -ENOENT;
1835}
1836
1837static void nfs_access_add_rbtree(struct inode *inode, struct nfs_access_entry *set)
1838{
Trond Myklebustcfcea3e2006-07-25 11:28:18 -04001839 struct nfs_inode *nfsi = NFS_I(inode);
1840 struct rb_root *root_node = &nfsi->access_cache;
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001841 struct rb_node **p = &root_node->rb_node;
1842 struct rb_node *parent = NULL;
1843 struct nfs_access_entry *entry;
1844
1845 spin_lock(&inode->i_lock);
1846 while (*p != NULL) {
1847 parent = *p;
1848 entry = rb_entry(parent, struct nfs_access_entry, rb_node);
1849
1850 if (set->cred < entry->cred)
1851 p = &parent->rb_left;
1852 else if (set->cred > entry->cred)
1853 p = &parent->rb_right;
1854 else
1855 goto found;
1856 }
1857 rb_link_node(&set->rb_node, parent, p);
1858 rb_insert_color(&set->rb_node, root_node);
Trond Myklebustcfcea3e2006-07-25 11:28:18 -04001859 list_add_tail(&set->lru, &nfsi->access_cache_entry_lru);
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001860 spin_unlock(&inode->i_lock);
1861 return;
1862found:
1863 rb_replace_node(parent, &set->rb_node, root_node);
Trond Myklebustcfcea3e2006-07-25 11:28:18 -04001864 list_add_tail(&set->lru, &nfsi->access_cache_entry_lru);
1865 list_del(&entry->lru);
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001866 spin_unlock(&inode->i_lock);
1867 nfs_access_free_entry(entry);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001868}
1869
Trond Myklebustaf22f942007-08-10 17:45:10 -04001870static void nfs_access_add_cache(struct inode *inode, struct nfs_access_entry *set)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001871{
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001872 struct nfs_access_entry *cache = kmalloc(sizeof(*cache), GFP_KERNEL);
1873 if (cache == NULL)
1874 return;
1875 RB_CLEAR_NODE(&cache->rb_node);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001876 cache->jiffies = set->jiffies;
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001877 cache->cred = get_rpccred(set->cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001878 cache->mask = set->mask;
Trond Myklebust1c3c07e2006-07-25 11:28:18 -04001879
1880 nfs_access_add_rbtree(inode, cache);
Trond Myklebustcfcea3e2006-07-25 11:28:18 -04001881
1882 /* Update accounting */
1883 smp_mb__before_atomic_inc();
1884 atomic_long_inc(&nfs_access_nr_entries);
1885 smp_mb__after_atomic_inc();
1886
1887 /* Add inode to global LRU list */
Trond Myklebust1a81bb82010-05-13 12:51:06 -04001888 if (!test_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags)) {
Trond Myklebustcfcea3e2006-07-25 11:28:18 -04001889 spin_lock(&nfs_access_lru_lock);
Trond Myklebust1a81bb82010-05-13 12:51:06 -04001890 if (!test_and_set_bit(NFS_INO_ACL_LRU_SET, &NFS_I(inode)->flags))
1891 list_add_tail(&NFS_I(inode)->access_cache_inode_lru,
1892 &nfs_access_lru_list);
Trond Myklebustcfcea3e2006-07-25 11:28:18 -04001893 spin_unlock(&nfs_access_lru_lock);
1894 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001895}
1896
1897static int nfs_do_access(struct inode *inode, struct rpc_cred *cred, int mask)
1898{
1899 struct nfs_access_entry cache;
1900 int status;
1901
1902 status = nfs_access_get_cached(inode, cred, &cache);
1903 if (status == 0)
1904 goto out;
1905
1906 /* Be clever: ask server to check for all possible rights */
1907 cache.mask = MAY_EXEC | MAY_WRITE | MAY_READ;
1908 cache.cred = cred;
1909 cache.jiffies = jiffies;
1910 status = NFS_PROTO(inode)->access(inode, &cache);
Suresh Jayaramana71ee332009-03-10 20:33:21 -04001911 if (status != 0) {
1912 if (status == -ESTALE) {
1913 nfs_zap_caches(inode);
1914 if (!S_ISDIR(inode->i_mode))
1915 set_bit(NFS_INO_STALE, &NFS_I(inode)->flags);
1916 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001917 return status;
Suresh Jayaramana71ee332009-03-10 20:33:21 -04001918 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001919 nfs_access_add_cache(inode, &cache);
1920out:
Al Viroe6305c42008-07-15 21:03:57 -04001921 if ((mask & ~cache.mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001922 return 0;
1923 return -EACCES;
1924}
1925
Trond Myklebustaf22f942007-08-10 17:45:10 -04001926static int nfs_open_permission_mask(int openflags)
1927{
1928 int mask = 0;
1929
1930 if (openflags & FMODE_READ)
1931 mask |= MAY_READ;
1932 if (openflags & FMODE_WRITE)
1933 mask |= MAY_WRITE;
1934 if (openflags & FMODE_EXEC)
1935 mask |= MAY_EXEC;
1936 return mask;
1937}
1938
1939int nfs_may_open(struct inode *inode, struct rpc_cred *cred, int openflags)
1940{
1941 return nfs_do_access(inode, cred, nfs_open_permission_mask(openflags));
1942}
1943
Al Viroe6305c42008-07-15 21:03:57 -04001944int nfs_permission(struct inode *inode, int mask)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001945{
1946 struct rpc_cred *cred;
1947 int res = 0;
1948
Chuck Lever91d5b472006-03-20 13:44:14 -05001949 nfs_inc_stats(inode, NFSIOS_VFSACCESS);
1950
Al Viroe6305c42008-07-15 21:03:57 -04001951 if ((mask & (MAY_READ | MAY_WRITE | MAY_EXEC)) == 0)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001952 goto out;
1953 /* Is this sys_access() ? */
Eric Paris9cfcac82010-07-23 11:43:51 -04001954 if (mask & (MAY_ACCESS | MAY_CHDIR))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001955 goto force_lookup;
1956
1957 switch (inode->i_mode & S_IFMT) {
1958 case S_IFLNK:
1959 goto out;
1960 case S_IFREG:
1961 /* NFSv4 has atomic_open... */
1962 if (nfs_server_capable(inode, NFS_CAP_ATOMIC_OPEN)
Frank Filz7ee2cb72009-05-18 17:41:40 -04001963 && (mask & MAY_OPEN)
1964 && !(mask & MAY_EXEC))
Linus Torvalds1da177e2005-04-16 15:20:36 -07001965 goto out;
1966 break;
1967 case S_IFDIR:
1968 /*
1969 * Optimize away all write operations, since the server
1970 * will check permissions when we perform the op.
1971 */
1972 if ((mask & MAY_WRITE) && !(mask & MAY_READ))
1973 goto out;
1974 }
1975
1976force_lookup:
Linus Torvalds1da177e2005-04-16 15:20:36 -07001977 if (!NFS_PROTO(inode)->access)
1978 goto out_notsup;
1979
Trond Myklebust98a8e322008-03-12 12:25:28 -04001980 cred = rpc_lookup_cred();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001981 if (!IS_ERR(cred)) {
1982 res = nfs_do_access(inode, cred, mask);
1983 put_rpccred(cred);
1984 } else
1985 res = PTR_ERR(cred);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001986out:
Miklos Szeredif696a362008-07-31 13:41:58 +02001987 if (!res && (mask & MAY_EXEC) && !execute_ok(inode))
1988 res = -EACCES;
1989
Chuck Lever1e7cb3d2006-03-20 13:44:24 -05001990 dfprintk(VFS, "NFS: permission(%s/%ld), mask=0x%x, res=%d\n",
1991 inode->i_sb->s_id, inode->i_ino, mask, res);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001992 return res;
1993out_notsup:
1994 res = nfs_revalidate_inode(NFS_SERVER(inode), inode);
1995 if (res == 0)
1996 res = generic_permission(inode, mask, NULL);
Chuck Lever1e7cb3d2006-03-20 13:44:24 -05001997 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001998}
1999
2000/*
2001 * Local variables:
2002 * version-control: t
2003 * kept-new-versions: 5
2004 * End:
2005 */