md/raid1: avoid reading known bad blocks during resync
[linux-2.6/x86.git] / fs / ext2 / namei.c
blobed5c5d496ee914aacd5e0d3ea6c7dcd98d319794
1 /*
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)
23 * from
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>
35 #include "ext2.h"
36 #include "xattr.h"
37 #include "acl.h"
38 #include "xip.h"
40 static inline int ext2_add_nondir(struct dentry *dentry, struct inode *inode)
42 int err = ext2_add_link(dentry, inode);
43 if (!err) {
44 d_instantiate(dentry, inode);
45 unlock_new_inode(inode);
46 return 0;
48 inode_dec_link_count(inode);
49 unlock_new_inode(inode);
50 iput(inode);
51 return err;
55 * Methods themselves.
58 static struct dentry *ext2_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd)
60 struct inode * inode;
61 ino_t ino;
63 if (dentry->d_name.len > EXT2_NAME_LEN)
64 return ERR_PTR(-ENAMETOOLONG);
66 ino = ext2_inode_by_name(dir, &dentry->d_name);
67 inode = NULL;
68 if (ino) {
69 inode = ext2_iget(dir->i_sb, ino);
70 if (IS_ERR(inode)) {
71 if (PTR_ERR(inode) == -ESTALE) {
72 ext2_error(dir->i_sb, __func__,
73 "deleted inode referenced: %lu",
74 (unsigned long) ino);
75 return ERR_PTR(-EIO);
76 } else {
77 return ERR_CAST(inode);
81 return d_splice_alias(inode, dentry);
84 struct dentry *ext2_get_parent(struct dentry *child)
86 struct qstr dotdot = {.name = "..", .len = 2};
87 unsigned long ino = ext2_inode_by_name(child->d_inode, &dotdot);
88 if (!ino)
89 return ERR_PTR(-ENOENT);
90 return d_obtain_alias(ext2_iget(child->d_inode->i_sb, ino));
94 * By the time this is called, we already have created
95 * the directory cache entry for the new file, but it
96 * is so far negative - it has no inode.
98 * If the create succeeds, we fill in the inode information
99 * with d_instantiate().
101 static int ext2_create (struct inode * dir, struct dentry * dentry, int mode, struct nameidata *nd)
103 struct inode *inode;
105 dquot_initialize(dir);
107 inode = ext2_new_inode(dir, mode, &dentry->d_name);
108 if (IS_ERR(inode))
109 return PTR_ERR(inode);
111 inode->i_op = &ext2_file_inode_operations;
112 if (ext2_use_xip(inode->i_sb)) {
113 inode->i_mapping->a_ops = &ext2_aops_xip;
114 inode->i_fop = &ext2_xip_file_operations;
115 } else if (test_opt(inode->i_sb, NOBH)) {
116 inode->i_mapping->a_ops = &ext2_nobh_aops;
117 inode->i_fop = &ext2_file_operations;
118 } else {
119 inode->i_mapping->a_ops = &ext2_aops;
120 inode->i_fop = &ext2_file_operations;
122 mark_inode_dirty(inode);
123 return ext2_add_nondir(dentry, inode);
126 static int ext2_mknod (struct inode * dir, struct dentry *dentry, int mode, dev_t rdev)
128 struct inode * inode;
129 int err;
131 if (!new_valid_dev(rdev))
132 return -EINVAL;
134 dquot_initialize(dir);
136 inode = ext2_new_inode (dir, mode, &dentry->d_name);
137 err = PTR_ERR(inode);
138 if (!IS_ERR(inode)) {
139 init_special_inode(inode, inode->i_mode, rdev);
140 #ifdef CONFIG_EXT2_FS_XATTR
141 inode->i_op = &ext2_special_inode_operations;
142 #endif
143 mark_inode_dirty(inode);
144 err = ext2_add_nondir(dentry, inode);
146 return err;
149 static int ext2_symlink (struct inode * dir, struct dentry * dentry,
150 const char * symname)
152 struct super_block * sb = dir->i_sb;
153 int err = -ENAMETOOLONG;
154 unsigned l = strlen(symname)+1;
155 struct inode * inode;
157 if (l > sb->s_blocksize)
158 goto out;
160 dquot_initialize(dir);
162 inode = ext2_new_inode (dir, S_IFLNK | S_IRWXUGO, &dentry->d_name);
163 err = PTR_ERR(inode);
164 if (IS_ERR(inode))
165 goto out;
167 if (l > sizeof (EXT2_I(inode)->i_data)) {
168 /* slow symlink */
169 inode->i_op = &ext2_symlink_inode_operations;
170 if (test_opt(inode->i_sb, NOBH))
171 inode->i_mapping->a_ops = &ext2_nobh_aops;
172 else
173 inode->i_mapping->a_ops = &ext2_aops;
174 err = page_symlink(inode, symname, l);
175 if (err)
176 goto out_fail;
177 } else {
178 /* fast symlink */
179 inode->i_op = &ext2_fast_symlink_inode_operations;
180 memcpy((char*)(EXT2_I(inode)->i_data),symname,l);
181 inode->i_size = l-1;
183 mark_inode_dirty(inode);
185 err = ext2_add_nondir(dentry, inode);
186 out:
187 return err;
189 out_fail:
190 inode_dec_link_count(inode);
191 unlock_new_inode(inode);
192 iput (inode);
193 goto out;
196 static int ext2_link (struct dentry * old_dentry, struct inode * dir,
197 struct dentry *dentry)
199 struct inode *inode = old_dentry->d_inode;
200 int err;
202 if (inode->i_nlink >= EXT2_LINK_MAX)
203 return -EMLINK;
205 dquot_initialize(dir);
207 inode->i_ctime = CURRENT_TIME_SEC;
208 inode_inc_link_count(inode);
209 ihold(inode);
211 err = ext2_add_link(dentry, inode);
212 if (!err) {
213 d_instantiate(dentry, inode);
214 return 0;
216 inode_dec_link_count(inode);
217 iput(inode);
218 return err;
221 static int ext2_mkdir(struct inode * dir, struct dentry * dentry, int mode)
223 struct inode * inode;
224 int err = -EMLINK;
226 if (dir->i_nlink >= EXT2_LINK_MAX)
227 goto out;
229 dquot_initialize(dir);
231 inode_inc_link_count(dir);
233 inode = ext2_new_inode(dir, S_IFDIR | mode, &dentry->d_name);
234 err = PTR_ERR(inode);
235 if (IS_ERR(inode))
236 goto out_dir;
238 inode->i_op = &ext2_dir_inode_operations;
239 inode->i_fop = &ext2_dir_operations;
240 if (test_opt(inode->i_sb, NOBH))
241 inode->i_mapping->a_ops = &ext2_nobh_aops;
242 else
243 inode->i_mapping->a_ops = &ext2_aops;
245 inode_inc_link_count(inode);
247 err = ext2_make_empty(inode, dir);
248 if (err)
249 goto out_fail;
251 err = ext2_add_link(dentry, inode);
252 if (err)
253 goto out_fail;
255 d_instantiate(dentry, inode);
256 unlock_new_inode(inode);
257 out:
258 return err;
260 out_fail:
261 inode_dec_link_count(inode);
262 inode_dec_link_count(inode);
263 unlock_new_inode(inode);
264 iput(inode);
265 out_dir:
266 inode_dec_link_count(dir);
267 goto out;
270 static int ext2_unlink(struct inode * dir, struct dentry *dentry)
272 struct inode * inode = dentry->d_inode;
273 struct ext2_dir_entry_2 * de;
274 struct page * page;
275 int err = -ENOENT;
277 dquot_initialize(dir);
279 de = ext2_find_entry (dir, &dentry->d_name, &page);
280 if (!de)
281 goto out;
283 err = ext2_delete_entry (de, page);
284 if (err)
285 goto out;
287 inode->i_ctime = dir->i_ctime;
288 inode_dec_link_count(inode);
289 err = 0;
290 out:
291 return err;
294 static int ext2_rmdir (struct inode * dir, struct dentry *dentry)
296 struct inode * inode = dentry->d_inode;
297 int err = -ENOTEMPTY;
299 if (ext2_empty_dir(inode)) {
300 err = ext2_unlink(dir, dentry);
301 if (!err) {
302 inode->i_size = 0;
303 inode_dec_link_count(inode);
304 inode_dec_link_count(dir);
307 return err;
310 static int ext2_rename (struct inode * old_dir, struct dentry * old_dentry,
311 struct inode * new_dir, struct dentry * new_dentry )
313 struct inode * old_inode = old_dentry->d_inode;
314 struct inode * new_inode = new_dentry->d_inode;
315 struct page * dir_page = NULL;
316 struct ext2_dir_entry_2 * dir_de = NULL;
317 struct page * old_page;
318 struct ext2_dir_entry_2 * old_de;
319 int err = -ENOENT;
321 dquot_initialize(old_dir);
322 dquot_initialize(new_dir);
324 old_de = ext2_find_entry (old_dir, &old_dentry->d_name, &old_page);
325 if (!old_de)
326 goto out;
328 if (S_ISDIR(old_inode->i_mode)) {
329 err = -EIO;
330 dir_de = ext2_dotdot(old_inode, &dir_page);
331 if (!dir_de)
332 goto out_old;
335 if (new_inode) {
336 struct page *new_page;
337 struct ext2_dir_entry_2 *new_de;
339 err = -ENOTEMPTY;
340 if (dir_de && !ext2_empty_dir (new_inode))
341 goto out_dir;
343 err = -ENOENT;
344 new_de = ext2_find_entry (new_dir, &new_dentry->d_name, &new_page);
345 if (!new_de)
346 goto out_dir;
347 ext2_set_link(new_dir, new_de, new_page, old_inode, 1);
348 new_inode->i_ctime = CURRENT_TIME_SEC;
349 if (dir_de)
350 drop_nlink(new_inode);
351 inode_dec_link_count(new_inode);
352 } else {
353 if (dir_de) {
354 err = -EMLINK;
355 if (new_dir->i_nlink >= EXT2_LINK_MAX)
356 goto out_dir;
358 err = ext2_add_link(new_dentry, old_inode);
359 if (err)
360 goto out_dir;
361 if (dir_de)
362 inode_inc_link_count(new_dir);
366 * Like most other Unix systems, set the ctime for inodes on a
367 * rename.
369 old_inode->i_ctime = CURRENT_TIME_SEC;
370 mark_inode_dirty(old_inode);
372 ext2_delete_entry (old_de, old_page);
374 if (dir_de) {
375 if (old_dir != new_dir)
376 ext2_set_link(old_inode, dir_de, dir_page, new_dir, 0);
377 else {
378 kunmap(dir_page);
379 page_cache_release(dir_page);
381 inode_dec_link_count(old_dir);
383 return 0;
386 out_dir:
387 if (dir_de) {
388 kunmap(dir_page);
389 page_cache_release(dir_page);
391 out_old:
392 kunmap(old_page);
393 page_cache_release(old_page);
394 out:
395 return err;
398 const struct inode_operations ext2_dir_inode_operations = {
399 .create = ext2_create,
400 .lookup = ext2_lookup,
401 .link = ext2_link,
402 .unlink = ext2_unlink,
403 .symlink = ext2_symlink,
404 .mkdir = ext2_mkdir,
405 .rmdir = ext2_rmdir,
406 .mknod = ext2_mknod,
407 .rename = ext2_rename,
408 #ifdef CONFIG_EXT2_FS_XATTR
409 .setxattr = generic_setxattr,
410 .getxattr = generic_getxattr,
411 .listxattr = ext2_listxattr,
412 .removexattr = generic_removexattr,
413 #endif
414 .setattr = ext2_setattr,
415 .check_acl = ext2_check_acl,
418 const struct inode_operations ext2_special_inode_operations = {
419 #ifdef CONFIG_EXT2_FS_XATTR
420 .setxattr = generic_setxattr,
421 .getxattr = generic_getxattr,
422 .listxattr = ext2_listxattr,
423 .removexattr = generic_removexattr,
424 #endif
425 .setattr = ext2_setattr,
426 .check_acl = ext2_check_acl,