2 * linux/fs/ext2/namei.c
4 * Rewrite to pagecache. Almost all code had been changed, so blame me
5 * if the things go wrong. Please, send bug reports to
6 * viro@parcelfarce.linux.theplanet.co.uk
8 * Stuff here is basically a glue between the VFS and generic UNIXish
9 * filesystem that keeps everything in pagecache. All knowledge of the
10 * directory layout is in fs/ext2/dir.c - it turned out to be easily separatable
11 * and it's easier to debug that way. In principle we might want to
12 * generalize that a bit and turn it into a library. Or not.
14 * The only non-static object here is ext2_dir_inode_operations.
16 * TODO: get rid of kmap() use, add readahead.
18 * Copyright (C) 1992, 1993, 1994, 1995
19 * Remy Card (card@masi.ibp.fr)
20 * Laboratoire MASI - Institut Blaise Pascal
21 * Universite Pierre et Marie Curie (Paris VI)
25 * linux/fs/minix/namei.c
27 * Copyright (C) 1991, 1992 Linus Torvalds
29 * Big-endian to little-endian byte-swapping/bitmaps by
30 * David S. Miller (davem@caip.rutgers.edu), 1995
33 #include <linux/pagemap.h>
34 #include <linux/quotaops.h>
39 static inline int ext2_add_nondir(struct dentry
*dentry
, struct inode
*inode
)
41 int err
= ext2_add_link(dentry
, inode
);
43 unlock_new_inode(inode
);
44 d_instantiate(dentry
, inode
);
47 inode_dec_link_count(inode
);
48 unlock_new_inode(inode
);
57 static struct dentry
*ext2_lookup(struct inode
* dir
, struct dentry
*dentry
, unsigned int flags
)
62 if (dentry
->d_name
.len
> EXT2_NAME_LEN
)
63 return ERR_PTR(-ENAMETOOLONG
);
65 ino
= ext2_inode_by_name(dir
, &dentry
->d_name
);
68 inode
= ext2_iget(dir
->i_sb
, ino
);
69 if (inode
== ERR_PTR(-ESTALE
)) {
70 ext2_error(dir
->i_sb
, __func__
,
71 "deleted inode referenced: %lu",
76 return d_splice_alias(inode
, dentry
);
79 struct dentry
*ext2_get_parent(struct dentry
*child
)
81 struct qstr dotdot
= QSTR_INIT("..", 2);
82 unsigned long ino
= ext2_inode_by_name(d_inode(child
), &dotdot
);
84 return ERR_PTR(-ENOENT
);
85 return d_obtain_alias(ext2_iget(d_inode(child
)->i_sb
, ino
));
89 * By the time this is called, we already have created
90 * the directory cache entry for the new file, but it
91 * is so far negative - it has no inode.
93 * If the create succeeds, we fill in the inode information
94 * with d_instantiate().
96 static int ext2_create (struct inode
* dir
, struct dentry
* dentry
, umode_t mode
, bool excl
)
101 err
= dquot_initialize(dir
);
105 inode
= ext2_new_inode(dir
, mode
, &dentry
->d_name
);
107 return PTR_ERR(inode
);
109 inode
->i_op
= &ext2_file_inode_operations
;
110 if (test_opt(inode
->i_sb
, NOBH
)) {
111 inode
->i_mapping
->a_ops
= &ext2_nobh_aops
;
112 inode
->i_fop
= &ext2_file_operations
;
114 inode
->i_mapping
->a_ops
= &ext2_aops
;
115 inode
->i_fop
= &ext2_file_operations
;
117 mark_inode_dirty(inode
);
118 return ext2_add_nondir(dentry
, inode
);
121 static int ext2_tmpfile(struct inode
*dir
, struct dentry
*dentry
, umode_t mode
)
123 struct inode
*inode
= ext2_new_inode(dir
, mode
, NULL
);
125 return PTR_ERR(inode
);
127 inode
->i_op
= &ext2_file_inode_operations
;
128 if (test_opt(inode
->i_sb
, NOBH
)) {
129 inode
->i_mapping
->a_ops
= &ext2_nobh_aops
;
130 inode
->i_fop
= &ext2_file_operations
;
132 inode
->i_mapping
->a_ops
= &ext2_aops
;
133 inode
->i_fop
= &ext2_file_operations
;
135 mark_inode_dirty(inode
);
136 d_tmpfile(dentry
, inode
);
137 unlock_new_inode(inode
);
141 static int ext2_mknod (struct inode
* dir
, struct dentry
*dentry
, umode_t mode
, dev_t rdev
)
143 struct inode
* inode
;
146 err
= dquot_initialize(dir
);
150 inode
= ext2_new_inode (dir
, mode
, &dentry
->d_name
);
151 err
= PTR_ERR(inode
);
152 if (!IS_ERR(inode
)) {
153 init_special_inode(inode
, inode
->i_mode
, rdev
);
154 #ifdef CONFIG_EXT2_FS_XATTR
155 inode
->i_op
= &ext2_special_inode_operations
;
157 mark_inode_dirty(inode
);
158 err
= ext2_add_nondir(dentry
, inode
);
163 static int ext2_symlink (struct inode
* dir
, struct dentry
* dentry
,
164 const char * symname
)
166 struct super_block
* sb
= dir
->i_sb
;
167 int err
= -ENAMETOOLONG
;
168 unsigned l
= strlen(symname
)+1;
169 struct inode
* inode
;
171 if (l
> sb
->s_blocksize
)
174 err
= dquot_initialize(dir
);
178 inode
= ext2_new_inode (dir
, S_IFLNK
| S_IRWXUGO
, &dentry
->d_name
);
179 err
= PTR_ERR(inode
);
183 if (l
> sizeof (EXT2_I(inode
)->i_data
)) {
185 inode
->i_op
= &ext2_symlink_inode_operations
;
186 if (test_opt(inode
->i_sb
, NOBH
))
187 inode
->i_mapping
->a_ops
= &ext2_nobh_aops
;
189 inode
->i_mapping
->a_ops
= &ext2_aops
;
190 err
= page_symlink(inode
, symname
, l
);
195 inode
->i_op
= &ext2_fast_symlink_inode_operations
;
196 inode
->i_link
= (char*)EXT2_I(inode
)->i_data
;
197 memcpy(inode
->i_link
, symname
, l
);
200 mark_inode_dirty(inode
);
202 err
= ext2_add_nondir(dentry
, inode
);
207 inode_dec_link_count(inode
);
208 unlock_new_inode(inode
);
213 static int ext2_link (struct dentry
* old_dentry
, struct inode
* dir
,
214 struct dentry
*dentry
)
216 struct inode
*inode
= d_inode(old_dentry
);
219 err
= dquot_initialize(dir
);
223 inode
->i_ctime
= CURRENT_TIME_SEC
;
224 inode_inc_link_count(inode
);
227 err
= ext2_add_link(dentry
, inode
);
229 d_instantiate(dentry
, inode
);
232 inode_dec_link_count(inode
);
237 static int ext2_mkdir(struct inode
* dir
, struct dentry
* dentry
, umode_t mode
)
239 struct inode
* inode
;
242 err
= dquot_initialize(dir
);
246 inode_inc_link_count(dir
);
248 inode
= ext2_new_inode(dir
, S_IFDIR
| mode
, &dentry
->d_name
);
249 err
= PTR_ERR(inode
);
253 inode
->i_op
= &ext2_dir_inode_operations
;
254 inode
->i_fop
= &ext2_dir_operations
;
255 if (test_opt(inode
->i_sb
, NOBH
))
256 inode
->i_mapping
->a_ops
= &ext2_nobh_aops
;
258 inode
->i_mapping
->a_ops
= &ext2_aops
;
260 inode_inc_link_count(inode
);
262 err
= ext2_make_empty(inode
, dir
);
266 err
= ext2_add_link(dentry
, inode
);
270 unlock_new_inode(inode
);
271 d_instantiate(dentry
, inode
);
276 inode_dec_link_count(inode
);
277 inode_dec_link_count(inode
);
278 unlock_new_inode(inode
);
281 inode_dec_link_count(dir
);
285 static int ext2_unlink(struct inode
* dir
, struct dentry
*dentry
)
287 struct inode
* inode
= d_inode(dentry
);
288 struct ext2_dir_entry_2
* de
;
292 err
= dquot_initialize(dir
);
296 de
= ext2_find_entry (dir
, &dentry
->d_name
, &page
);
302 err
= ext2_delete_entry (de
, page
);
306 inode
->i_ctime
= dir
->i_ctime
;
307 inode_dec_link_count(inode
);
313 static int ext2_rmdir (struct inode
* dir
, struct dentry
*dentry
)
315 struct inode
* inode
= d_inode(dentry
);
316 int err
= -ENOTEMPTY
;
318 if (ext2_empty_dir(inode
)) {
319 err
= ext2_unlink(dir
, dentry
);
322 inode_dec_link_count(inode
);
323 inode_dec_link_count(dir
);
329 static int ext2_rename (struct inode
* old_dir
, struct dentry
* old_dentry
,
330 struct inode
* new_dir
, struct dentry
* new_dentry
)
332 struct inode
* old_inode
= d_inode(old_dentry
);
333 struct inode
* new_inode
= d_inode(new_dentry
);
334 struct page
* dir_page
= NULL
;
335 struct ext2_dir_entry_2
* dir_de
= NULL
;
336 struct page
* old_page
;
337 struct ext2_dir_entry_2
* old_de
;
340 err
= dquot_initialize(old_dir
);
344 err
= dquot_initialize(new_dir
);
348 old_de
= ext2_find_entry (old_dir
, &old_dentry
->d_name
, &old_page
);
354 if (S_ISDIR(old_inode
->i_mode
)) {
356 dir_de
= ext2_dotdot(old_inode
, &dir_page
);
362 struct page
*new_page
;
363 struct ext2_dir_entry_2
*new_de
;
366 if (dir_de
&& !ext2_empty_dir (new_inode
))
370 new_de
= ext2_find_entry (new_dir
, &new_dentry
->d_name
, &new_page
);
373 ext2_set_link(new_dir
, new_de
, new_page
, old_inode
, 1);
374 new_inode
->i_ctime
= CURRENT_TIME_SEC
;
376 drop_nlink(new_inode
);
377 inode_dec_link_count(new_inode
);
379 err
= ext2_add_link(new_dentry
, old_inode
);
383 inode_inc_link_count(new_dir
);
387 * Like most other Unix systems, set the ctime for inodes on a
390 old_inode
->i_ctime
= CURRENT_TIME_SEC
;
391 mark_inode_dirty(old_inode
);
393 ext2_delete_entry (old_de
, old_page
);
396 if (old_dir
!= new_dir
)
397 ext2_set_link(old_inode
, dir_de
, dir_page
, new_dir
, 0);
400 page_cache_release(dir_page
);
402 inode_dec_link_count(old_dir
);
410 page_cache_release(dir_page
);
414 page_cache_release(old_page
);
419 const struct inode_operations ext2_dir_inode_operations
= {
420 .create
= ext2_create
,
421 .lookup
= ext2_lookup
,
423 .unlink
= ext2_unlink
,
424 .symlink
= ext2_symlink
,
428 .rename
= ext2_rename
,
429 #ifdef CONFIG_EXT2_FS_XATTR
430 .setxattr
= generic_setxattr
,
431 .getxattr
= generic_getxattr
,
432 .listxattr
= ext2_listxattr
,
433 .removexattr
= generic_removexattr
,
435 .setattr
= ext2_setattr
,
436 .get_acl
= ext2_get_acl
,
437 .set_acl
= ext2_set_acl
,
438 .tmpfile
= ext2_tmpfile
,
441 const struct inode_operations ext2_special_inode_operations
= {
442 #ifdef CONFIG_EXT2_FS_XATTR
443 .setxattr
= generic_setxattr
,
444 .getxattr
= generic_getxattr
,
445 .listxattr
= ext2_listxattr
,
446 .removexattr
= generic_removexattr
,
448 .setattr
= ext2_setattr
,
449 .get_acl
= ext2_get_acl
,
450 .set_acl
= ext2_set_acl
,