3 * This code is issued under the GNU General Public License.
4 * See the file COPYING in this distribution
6 * Copyright (C) 1992, 1993, 1994, 1995
7 * Remy Card (card@masi.ibp.fr)
8 * Laboratoire MASI - Institut Blaise Pascal
9 * Universite Pierre et Marie Curie (Paris VI)
13 * linux/fs/ext2/namei.c
15 * Copyright (C) 1991, 1992 Linus Torvalds
17 * Big-endian to little-endian byte-swapping/bitmaps by
18 * David S. Miller (davem@caip.rutgers.edu), 1995
19 * Directory entry file type support and forward compatibility hooks
20 * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998
22 * Changes for use in OBDFS
23 * Copyright (c) 1999, Seagate Technology Inc.
24 * Copyright (C) 2001, Cluster File Systems, Inc.
25 * Rewritten based on recent ext2 page cache use.
30 #include <linux/locks.h>
31 #include <linux/quotaops.h>
32 #include <linux/obd_support.h>
33 #include <linux/lustre_light.h>
34 extern struct address_space_operations ll_aops;
37 extern void ll_change_inode(struct inode *inode);
38 extern int ll_setattr(struct dentry *de, struct iattr *attr);
41 extern int ext2_add_link (struct dentry *dentry, struct inode *inode);
42 ino_t ll_inode_by_name(struct inode * dir, struct dentry *dentry, int *typ);
43 int ext2_make_empty(struct inode *inode, struct inode *parent);
44 struct ext2_dir_entry_2 * ext2_find_entry (struct inode * dir,
45 struct dentry *dentry, struct page ** res_page);
46 int ext2_delete_entry (struct ext2_dir_entry_2 * dir, struct page * page );
47 int ext2_empty_dir (struct inode * inode);
48 struct ext2_dir_entry_2 * ext2_dotdot (struct inode *dir, struct page **p);
49 void ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de,
50 struct page *page, struct inode *inode);
53 * Couple of helper functions - make the code slightly cleaner.
55 static inline void ext2_inc_count(struct inode *inode)
58 ll_change_inode(inode);
61 /* postpone the disk update until the inode really goes away */
62 static inline void ext2_dec_count(struct inode *inode)
65 if (inode->i_nlink > 0)
66 ll_change_inode(inode);
69 static inline int ext2_add_nondir(struct dentry *dentry, struct inode *inode)
72 err = ext2_add_link(dentry, inode);
74 d_instantiate(dentry, inode);
77 ext2_dec_count(inode);
83 static struct dentry *ll_lookup(struct inode * dir, struct dentry *dentry)
86 struct mds_rep_hdr *hdr = NULL;
87 struct inode * inode = NULL;
93 if (dentry->d_name.len > EXT2_NAME_LEN)
94 return ERR_PTR(-ENAMETOOLONG);
96 ino = ll_inode_by_name(dir, dentry, &type);
100 err = mdc_getattr(ino, type, OBD_MD_FLNOTOBD|OBD_MD_FLBLOCKS,
103 printk(__FUNCTION__ ": obdo_fromid failed\n");
105 return ERR_PTR(-EACCES);
108 inode = iget4(dir->i_sb, ino, NULL, rep);
112 return ERR_PTR(-EACCES);
115 d_add(dentry, inode);
121 * NOTE! unlike strncmp, ext2_match returns 1 for success, 0 for failure.
123 * `len <= EXT2_NAME_LEN' is guaranteed by caller.
124 * `de != NULL' is guaranteed by caller.
126 static inline int ext2_match (int len, const char * const name,
127 struct ext2_dir_entry_2 * de)
129 if (len != de->name_len)
133 return !memcmp(name, de->name, len);
136 static struct inode *ll_new_inode(struct inode *dir, int mode)
147 return ERR_PTR(-ENOMEM);
150 /* Send a hint to the create method on the type of file to create */
152 oa->o_valid |= OBD_MD_FLMODE;
153 CDEBUG(D_INODE, "\n");
154 err = obd_create(IID(dir), oa);
155 CDEBUG(D_INODE, "\n");
158 printk("new_inode - fatal: err %d\n", err);
163 CDEBUG(D_INODE, "obdo mode %o\n", oa->o_mode);
165 inode = iget4(dir->i_sb, (ino_t)oa->o_id, NULL, oa);
166 CDEBUG(D_INODE, "\n");
170 printk("new_inode -fatal: %ld\n", (long)oa->o_id);
171 obd_destroy(IID(dir), oa);
173 return ERR_PTR(-EIO);
176 if (!list_empty(&inode->i_dentry)) {
177 printk("new_inode -fatal: aliases %ld, ct %d lnk %d\n",
179 atomic_read(&inode->i_count),
181 obd_destroy(IID(dir), oa);
184 return ERR_PTR(-EIO);
193 * By the time this is called, we already have created
194 * the directory cache entry for the new file, but it
195 * is so far negative - it has no inode.
197 * If the create succeeds, we fill in the inode information
198 * with d_instantiate().
200 static int ll_create (struct inode * dir, struct dentry * dentry, int mode)
202 struct inode * inode = ll_new_inode (dir, mode);
203 int err = PTR_ERR(inode);
204 if (!IS_ERR(inode)) {
205 inode->i_op = &ll_file_inode_operations;
206 inode->i_fop = &ll_file_operations;
207 inode->i_mapping->a_ops = &ll_aops;
208 err = ext2_add_nondir(dentry, inode);
214 static int ll_mknod (struct inode * dir, struct dentry *dentry, int mode, int rdev)
216 struct inode * inode = ll_new_inode (dir, mode);
217 int err = PTR_ERR(inode);
218 if (!IS_ERR(inode)) {
219 init_special_inode(inode, mode, rdev);
220 ll_change_inode(inode);
221 err = ext2_add_nondir(dentry, inode);
226 static int ll_symlink (struct inode * dir, struct dentry * dentry,
227 const char * symname)
229 struct super_block * sb = dir->i_sb;
230 int err = -ENAMETOOLONG;
231 unsigned l = strlen(symname)+1;
232 struct inode * inode;
233 struct ll_inode_info *oinfo;
235 if (l > sb->s_blocksize)
238 inode = ll_new_inode (dir, S_IFLNK | S_IRWXUGO);
239 err = PTR_ERR(inode);
243 oinfo = ll_i2info(inode);
244 if (l >= sizeof(oinfo->lli_inline)) {
246 inode->i_op = &page_symlink_inode_operations;
247 inode->i_mapping->a_ops = &ll_aops;
248 err = block_symlink(inode, symname, l);
253 inode->i_op = &ll_fast_symlink_inode_operations;
254 memcpy(oinfo->lli_inline, symname, l);
257 ll_change_inode(inode);
259 err = ext2_add_nondir(dentry, inode);
264 ext2_dec_count(inode);
271 static int ll_link (struct dentry * old_dentry, struct inode * dir,
272 struct dentry *dentry)
274 struct inode *inode = old_dentry->d_inode;
276 if (S_ISDIR(inode->i_mode))
279 if (inode->i_nlink >= EXT2_LINK_MAX)
282 inode->i_ctime = CURRENT_TIME;
283 ext2_inc_count(inode);
284 atomic_inc(&inode->i_count);
286 return ext2_add_nondir(dentry, inode);
290 static int ll_mkdir(struct inode * dir, struct dentry * dentry, int mode)
292 struct inode * inode;
296 if (dir->i_nlink >= EXT2_LINK_MAX)
301 inode = ll_new_inode (dir, S_IFDIR | mode);
302 err = PTR_ERR(inode);
306 inode->i_op = &ll_dir_inode_operations;
307 inode->i_fop = &ll_dir_operations;
308 inode->i_mapping->a_ops = &ll_aops;
310 ext2_inc_count(inode);
312 err = ext2_make_empty(inode, dir);
316 err = ext2_add_link(dentry, inode);
320 d_instantiate(dentry, inode);
326 ext2_dec_count(inode);
327 ext2_dec_count(inode);
336 static int ll_unlink(struct inode * dir, struct dentry *dentry)
338 struct inode * inode = dentry->d_inode;
339 struct ext2_dir_entry_2 * de;
343 de = ext2_find_entry (dir, dentry, &page);
347 err = ext2_delete_entry (de, page);
351 inode->i_ctime = dir->i_ctime;
352 ext2_dec_count(inode);
359 static int ll_rmdir (struct inode * dir, struct dentry *dentry)
361 struct inode * inode = dentry->d_inode;
362 int err = -ENOTEMPTY;
364 if (ext2_empty_dir(inode)) {
365 err = ll_unlink(dir, dentry);
368 ext2_dec_count(inode);
375 static int ll_rename (struct inode * old_dir, struct dentry * old_dentry,
376 struct inode * new_dir, struct dentry * new_dentry )
378 struct inode * old_inode = old_dentry->d_inode;
379 struct inode * new_inode = new_dentry->d_inode;
380 struct page * dir_page = NULL;
381 struct ext2_dir_entry_2 * dir_de = NULL;
382 struct page * old_page;
383 struct ext2_dir_entry_2 * old_de;
386 old_de = ext2_find_entry (old_dir, old_dentry, &old_page);
390 if (S_ISDIR(old_inode->i_mode)) {
392 dir_de = ext2_dotdot(old_inode, &dir_page);
398 struct page *new_page;
399 struct ext2_dir_entry_2 *new_de;
402 if (dir_de && !ext2_empty_dir (new_inode))
406 new_de = ext2_find_entry (new_dir, new_dentry, &new_page);
409 ext2_inc_count(old_inode);
410 ext2_set_link(new_dir, new_de, new_page, old_inode);
411 new_inode->i_ctime = CURRENT_TIME;
413 new_inode->i_nlink--;
414 ext2_dec_count(new_inode);
418 if (new_dir->i_nlink >= EXT2_LINK_MAX)
421 ext2_inc_count(old_inode);
422 err = ext2_add_link(new_dentry, old_inode);
424 ext2_dec_count(old_inode);
428 ext2_inc_count(new_dir);
431 ext2_delete_entry (old_de, old_page);
432 ext2_dec_count(old_inode);
435 ext2_set_link(old_inode, dir_de, dir_page, new_dir);
436 ext2_dec_count(old_dir);
444 page_cache_release(dir_page);
448 page_cache_release(old_page);
453 struct inode_operations ll_dir_inode_operations = {