2 * linux/fs/obdfs/namei.c
4 * This code is issued under the GNU General Public License.
5 * See the file COPYING in this distribution
7 * Copyright (C) 1992, 1993, 1994, 1995
8 * Remy Card (card@masi.ibp.fr)
9 * Laboratoire MASI - Institut Blaise Pascal
10 * Universite Pierre et Marie Curie (Paris VI)
14 * linux/fs/ext2/namei.c
16 * Copyright (C) 1991, 1992 Linus Torvalds
18 * Big-endian to little-endian byte-swapping/bitmaps by
19 * David S. Miller (davem@caip.rutgers.edu), 1995
20 * Directory entry file type support and forward compatibility hooks
21 * for B-tree directories by Theodore Ts'o (tytso@mit.edu), 1998
23 * Changes for use in OBDFS
24 * Copyright (c) 1999, Seagate Technology Inc.
25 * Copyright (C) 2001, Cluster File Systems, Inc.
26 * Rewritten based on recent ext2 page cache use.
31 #include <linux/locks.h>
32 #include <linux/quotaops.h>
33 #include <linux/obd_support.h>
34 #include <linux/obdfs.h>
35 extern struct address_space_operations obdfs_aops;
38 extern int ext2_add_link (struct dentry *dentry, struct inode *inode);
39 extern ino_t ext2_inode_by_name(struct inode * dir, struct dentry *dentry);
40 int ext2_make_empty(struct inode *inode, struct inode *parent);
41 struct ext2_dir_entry_2 * ext2_find_entry (struct inode * dir,
42 struct dentry *dentry, struct page ** res_page);
43 int ext2_delete_entry (struct ext2_dir_entry_2 * dir, struct page * page );
44 int ext2_empty_dir (struct inode * inode);
45 struct ext2_dir_entry_2 * ext2_dotdot (struct inode *dir, struct page **p);
46 void ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de,
47 struct page *page, struct inode *inode);
50 * Couple of helper functions - make the code slightly cleaner.
52 static inline void ext2_inc_count(struct inode *inode)
55 mark_inode_dirty(inode);
58 static inline void ext2_dec_count(struct inode *inode)
61 mark_inode_dirty(inode);
64 static inline int ext2_add_nondir(struct dentry *dentry, struct inode *inode)
66 int err = ext2_add_link(dentry, inode);
68 d_instantiate(dentry, inode);
71 ext2_dec_count(inode);
77 static struct dentry *obdfs_lookup(struct inode * dir, struct dentry *dentry)
82 if (dentry->d_name.len > EXT2_NAME_LEN)
83 return ERR_PTR(-ENAMETOOLONG);
85 ino = ext2_inode_by_name(dir, dentry);
88 inode = iget(dir->i_sb, ino);
90 return ERR_PTR(-EACCES);
98 * NOTE! unlike strncmp, ext2_match returns 1 for success, 0 for failure.
100 * `len <= EXT2_NAME_LEN' is guaranteed by caller.
101 * `de != NULL' is guaranteed by caller.
103 static inline int ext2_match (int len, const char * const name,
104 struct ext2_dir_entry_2 * de)
106 if (len != de->name_len)
110 return !memcmp(name, de->name, len);
113 static struct inode *obdfs_new_inode(struct inode *dir, int mode)
120 if (IOPS(dir, create) == NULL) {
121 printk(KERN_ERR __FUNCTION__ ": no create method!\n");
123 return ERR_PTR(-EIO);
128 return ERR_PTR(-ENOMEM);
131 /* Send a hint to the create method on the type of file to create */
133 oa->o_valid |= OBD_MD_FLMODE;
135 err = IOPS(dir, create)(IID(dir), oa);
138 CDEBUG(D_INODE, "fatal: creating new inode (err %d)\n", err);
144 inode = iget(dir->i_sb, (ino_t)oa->o_id);
147 CDEBUG(D_INODE, "fatal: get new inode %ld\n", (long)oa->o_id);
148 IOPS(dir, destroy)(IID(dir), oa);
151 return ERR_PTR(-EIO);
154 if (!list_empty(&inode->i_dentry)) {
155 CDEBUG(D_INODE, "New inode (%ld) has aliases!\n", inode->i_ino);
156 IOPS(dir, destroy)(IID(dir), oa);
160 return ERR_PTR(-EIO);
166 } /* obdfs_new_inode */
170 * By the time this is called, we already have created
171 * the directory cache entry for the new file, but it
172 * is so far negative - it has no inode.
174 * If the create succeeds, we fill in the inode information
175 * with d_instantiate().
177 static int obdfs_create (struct inode * dir, struct dentry * dentry, int mode)
179 struct inode * inode = obdfs_new_inode (dir, mode);
180 int err = PTR_ERR(inode);
181 if (!IS_ERR(inode)) {
182 inode->i_op = &obdfs_file_inode_operations;
183 inode->i_fop = &obdfs_file_operations;
184 inode->i_mapping->a_ops = &obdfs_aops;
185 mark_inode_dirty(inode);
186 err = ext2_add_nondir(dentry, inode);
192 static int obdfs_mknod (struct inode * dir, struct dentry *dentry, int mode, int rdev)
194 struct inode * inode = obdfs_new_inode (dir, mode);
195 int err = PTR_ERR(inode);
196 if (!IS_ERR(inode)) {
197 init_special_inode(inode, mode, rdev);
198 mark_inode_dirty(inode);
199 err = ext2_add_nondir(dentry, inode);
204 static int obdfs_symlink (struct inode * dir, struct dentry * dentry,
205 const char * symname)
207 struct super_block * sb = dir->i_sb;
208 int err = -ENAMETOOLONG;
209 unsigned l = strlen(symname)+1;
210 struct inode * inode;
211 struct obdfs_inode_info *oinfo;
212 oinfo = obdfs_i2info(inode);
214 if (l > sb->s_blocksize)
217 inode = obdfs_new_inode (dir, S_IFLNK | S_IRWXUGO);
218 err = PTR_ERR(inode);
222 if (l >= sizeof(oinfo->oi_inline)) {
224 inode->i_op = &obdfs_symlink_inode_operations;
225 inode->i_mapping->a_ops = &obdfs_aops;
226 err = block_symlink(inode, symname, l);
231 inode->i_op = &obdfs_fast_symlink_inode_operations;
232 memcpy((char*)&inode->u.ext2_i.i_data,symname,l);
235 mark_inode_dirty(inode);
237 err = ext2_add_nondir(dentry, inode);
242 ext2_dec_count(inode);
249 static int obdfs_link (struct dentry * old_dentry, struct inode * dir,
250 struct dentry *dentry)
252 struct inode *inode = old_dentry->d_inode;
254 if (S_ISDIR(inode->i_mode))
257 if (inode->i_nlink >= EXT2_LINK_MAX)
260 inode->i_ctime = CURRENT_TIME;
261 ext2_inc_count(inode);
262 atomic_inc(&inode->i_count);
264 return ext2_add_nondir(dentry, inode);
268 static int obdfs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
270 struct inode * inode;
273 if (dir->i_nlink >= EXT2_LINK_MAX)
278 inode = obdfs_new_inode (dir, S_IFDIR | mode);
279 err = PTR_ERR(inode);
283 inode->i_op = &obdfs_dir_inode_operations;
284 inode->i_fop = &obdfs_dir_operations;
285 inode->i_mapping->a_ops = &obdfs_aops;
287 ext2_inc_count(inode);
289 err = ext2_make_empty(inode, dir);
293 err = ext2_add_link(dentry, inode);
297 d_instantiate(dentry, inode);
302 ext2_dec_count(inode);
303 ext2_dec_count(inode);
310 static int obdfs_unlink(struct inode * dir, struct dentry *dentry)
312 struct inode * inode = dentry->d_inode;
313 struct ext2_dir_entry_2 * de;
317 de = ext2_find_entry (dir, dentry, &page);
321 err = ext2_delete_entry (de, page);
325 inode->i_ctime = dir->i_ctime;
326 ext2_dec_count(inode);
333 static int obdfs_rmdir (struct inode * dir, struct dentry *dentry)
335 struct inode * inode = dentry->d_inode;
336 int err = -ENOTEMPTY;
338 if (ext2_empty_dir(inode)) {
339 err = obdfs_unlink(dir, dentry);
342 ext2_dec_count(inode);
349 static int obdfs_rename (struct inode * old_dir, struct dentry * old_dentry,
350 struct inode * new_dir, struct dentry * new_dentry )
352 struct inode * old_inode = old_dentry->d_inode;
353 struct inode * new_inode = new_dentry->d_inode;
354 struct page * dir_page = NULL;
355 struct ext2_dir_entry_2 * dir_de = NULL;
356 struct page * old_page;
357 struct ext2_dir_entry_2 * old_de;
360 old_de = ext2_find_entry (old_dir, old_dentry, &old_page);
364 if (S_ISDIR(old_inode->i_mode)) {
366 dir_de = ext2_dotdot(old_inode, &dir_page);
372 struct page *new_page;
373 struct ext2_dir_entry_2 *new_de;
376 if (dir_de && !ext2_empty_dir (new_inode))
380 new_de = ext2_find_entry (new_dir, new_dentry, &new_page);
383 ext2_inc_count(old_inode);
384 ext2_set_link(new_dir, new_de, new_page, old_inode);
385 new_inode->i_ctime = CURRENT_TIME;
387 new_inode->i_nlink--;
388 ext2_dec_count(new_inode);
392 if (new_dir->i_nlink >= EXT2_LINK_MAX)
395 ext2_inc_count(old_inode);
396 err = ext2_add_link(new_dentry, old_inode);
398 ext2_dec_count(old_inode);
402 ext2_inc_count(new_dir);
405 ext2_delete_entry (old_de, old_page);
406 ext2_dec_count(old_inode);
409 ext2_set_link(old_inode, dir_de, dir_page, new_dir);
410 ext2_dec_count(old_dir);
418 page_cache_release(dir_page);
422 page_cache_release(old_page);
427 struct inode_operations obdfs_dir_inode_operations = {
428 create: obdfs_create,
429 lookup: obdfs_lookup,
431 unlink: obdfs_unlink,
432 symlink: obdfs_symlink,
436 rename: obdfs_rename,