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 void obdfs_change_inode(struct inode *inode);
39 extern int obdfs_setattr(struct dentry *de, struct iattr *attr);
42 extern int ext2_add_link (struct dentry *dentry, struct inode *inode);
43 ino_t obdfs_inode_by_name(struct inode * dir, struct dentry *dentry, int *typ);
44 int ext2_make_empty(struct inode *inode, struct inode *parent);
45 struct ext2_dir_entry_2 * ext2_find_entry (struct inode * dir,
46 struct dentry *dentry, struct page ** res_page);
47 int ext2_delete_entry (struct ext2_dir_entry_2 * dir, struct page * page );
48 int ext2_empty_dir (struct inode * inode);
49 struct ext2_dir_entry_2 * ext2_dotdot (struct inode *dir, struct page **p);
50 void ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de,
51 struct page *page, struct inode *inode);
54 * Couple of helper functions - make the code slightly cleaner.
56 static inline void ext2_inc_count(struct inode *inode)
59 obdfs_change_inode(inode);
62 /* postpone the disk update until the inode really goes away */
63 static inline void ext2_dec_count(struct inode *inode)
66 if (inode->i_nlink > 0)
67 obdfs_change_inode(inode);
70 static inline int ext2_add_nondir(struct dentry *dentry, struct inode *inode)
73 err = ext2_add_link(dentry, inode);
75 d_instantiate(dentry, inode);
78 ext2_dec_count(inode);
84 static struct dentry *obdfs_lookup(struct inode * dir, struct dentry *dentry)
87 struct inode * inode = NULL;
92 if (dentry->d_name.len > EXT2_NAME_LEN)
93 return ERR_PTR(-ENAMETOOLONG);
95 ino = obdfs_inode_by_name(dir, dentry, &type);
99 oa = obdo_fromid(IID(dir), ino, type,
100 OBD_MD_FLNOTOBD | OBD_MD_FLBLOCKS);
102 printk(__FUNCTION__ ": obdo_fromid failed\n");
104 return ERR_PTR(-EACCES);
107 inode = iget4(dir->i_sb, ino, NULL, oa);
111 return ERR_PTR(-EACCES);
114 d_add(dentry, inode);
120 * NOTE! unlike strncmp, ext2_match returns 1 for success, 0 for failure.
122 * `len <= EXT2_NAME_LEN' is guaranteed by caller.
123 * `de != NULL' is guaranteed by caller.
125 static inline int ext2_match (int len, const char * const name,
126 struct ext2_dir_entry_2 * de)
128 if (len != de->name_len)
132 return !memcmp(name, de->name, len);
135 static struct inode *obdfs_new_inode(struct inode *dir, int mode)
142 if (IOPS(dir, create) == NULL) {
143 printk(KERN_ERR __FUNCTION__ ": no create method!\n");
145 return ERR_PTR(-EIO);
150 return ERR_PTR(-ENOMEM);
153 /* Send a hint to the create method on the type of file to create */
155 oa->o_valid |= OBD_MD_FLMODE;
156 CDEBUG(D_INODE, "\n");
157 err = IOPS(dir, create)(IID(dir), oa);
158 CDEBUG(D_INODE, "\n");
161 printk("new_inode - fatal: err %d\n", err);
166 CDEBUG(D_INODE, "obdo mode %o\n", oa->o_mode);
168 inode = iget4(dir->i_sb, (ino_t)oa->o_id, NULL, oa);
169 CDEBUG(D_INODE, "\n");
173 printk("new_inode -fatal: %ld\n", (long)oa->o_id);
174 IOPS(dir, destroy)(IID(dir), oa);
176 return ERR_PTR(-EIO);
179 if (!list_empty(&inode->i_dentry)) {
180 printk("new_inode -fatal: aliases %ld, ct %d lnk %d\n",
182 atomic_read(&inode->i_count),
184 IOPS(dir, destroy)(IID(dir), oa);
187 return ERR_PTR(-EIO);
192 } /* obdfs_new_inode */
196 * By the time this is called, we already have created
197 * the directory cache entry for the new file, but it
198 * is so far negative - it has no inode.
200 * If the create succeeds, we fill in the inode information
201 * with d_instantiate().
203 static int obdfs_create (struct inode * dir, struct dentry * dentry, int mode)
205 struct inode * inode = obdfs_new_inode (dir, mode);
206 int err = PTR_ERR(inode);
207 if (!IS_ERR(inode)) {
208 inode->i_op = &obdfs_file_inode_operations;
209 inode->i_fop = &obdfs_file_operations;
210 inode->i_mapping->a_ops = &obdfs_aops;
211 err = ext2_add_nondir(dentry, inode);
217 static int obdfs_mknod (struct inode * dir, struct dentry *dentry, int mode, int rdev)
219 struct inode * inode = obdfs_new_inode (dir, mode);
220 int err = PTR_ERR(inode);
221 if (!IS_ERR(inode)) {
222 init_special_inode(inode, mode, rdev);
223 obdfs_change_inode(inode);
224 err = ext2_add_nondir(dentry, inode);
229 static int obdfs_symlink (struct inode * dir, struct dentry * dentry,
230 const char * symname)
232 struct super_block * sb = dir->i_sb;
233 int err = -ENAMETOOLONG;
234 unsigned l = strlen(symname)+1;
235 struct inode * inode;
236 struct obdfs_inode_info *oinfo;
238 if (l > sb->s_blocksize)
241 inode = obdfs_new_inode (dir, S_IFLNK | S_IRWXUGO);
242 err = PTR_ERR(inode);
246 oinfo = obdfs_i2info(inode);
247 if (l >= sizeof(oinfo->oi_inline)) {
249 inode->i_op = &page_symlink_inode_operations;
250 inode->i_mapping->a_ops = &obdfs_aops;
251 err = block_symlink(inode, symname, l);
256 inode->i_op = &obdfs_fast_symlink_inode_operations;
257 memcpy(oinfo->oi_inline, symname, l);
260 obdfs_change_inode(inode);
262 err = ext2_add_nondir(dentry, inode);
267 ext2_dec_count(inode);
274 static int obdfs_link (struct dentry * old_dentry, struct inode * dir,
275 struct dentry *dentry)
277 struct inode *inode = old_dentry->d_inode;
279 if (S_ISDIR(inode->i_mode))
282 if (inode->i_nlink >= EXT2_LINK_MAX)
285 inode->i_ctime = CURRENT_TIME;
286 ext2_inc_count(inode);
287 atomic_inc(&inode->i_count);
289 return ext2_add_nondir(dentry, inode);
293 static int obdfs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
295 struct inode * inode;
299 if (dir->i_nlink >= EXT2_LINK_MAX)
304 inode = obdfs_new_inode (dir, S_IFDIR | mode);
305 err = PTR_ERR(inode);
309 inode->i_op = &obdfs_dir_inode_operations;
310 inode->i_fop = &obdfs_dir_operations;
311 inode->i_mapping->a_ops = &obdfs_aops;
313 ext2_inc_count(inode);
315 err = ext2_make_empty(inode, dir);
319 err = ext2_add_link(dentry, inode);
323 d_instantiate(dentry, inode);
329 ext2_dec_count(inode);
330 ext2_dec_count(inode);
339 static int obdfs_unlink(struct inode * dir, struct dentry *dentry)
341 struct inode * inode = dentry->d_inode;
342 struct ext2_dir_entry_2 * de;
346 de = ext2_find_entry (dir, dentry, &page);
350 err = ext2_delete_entry (de, page);
354 inode->i_ctime = dir->i_ctime;
355 ext2_dec_count(inode);
362 static int obdfs_rmdir (struct inode * dir, struct dentry *dentry)
364 struct inode * inode = dentry->d_inode;
365 int err = -ENOTEMPTY;
367 if (ext2_empty_dir(inode)) {
368 err = obdfs_unlink(dir, dentry);
371 ext2_dec_count(inode);
378 static int obdfs_rename (struct inode * old_dir, struct dentry * old_dentry,
379 struct inode * new_dir, struct dentry * new_dentry )
381 struct inode * old_inode = old_dentry->d_inode;
382 struct inode * new_inode = new_dentry->d_inode;
383 struct page * dir_page = NULL;
384 struct ext2_dir_entry_2 * dir_de = NULL;
385 struct page * old_page;
386 struct ext2_dir_entry_2 * old_de;
389 old_de = ext2_find_entry (old_dir, old_dentry, &old_page);
393 if (S_ISDIR(old_inode->i_mode)) {
395 dir_de = ext2_dotdot(old_inode, &dir_page);
401 struct page *new_page;
402 struct ext2_dir_entry_2 *new_de;
405 if (dir_de && !ext2_empty_dir (new_inode))
409 new_de = ext2_find_entry (new_dir, new_dentry, &new_page);
412 ext2_inc_count(old_inode);
413 ext2_set_link(new_dir, new_de, new_page, old_inode);
414 new_inode->i_ctime = CURRENT_TIME;
416 new_inode->i_nlink--;
417 ext2_dec_count(new_inode);
421 if (new_dir->i_nlink >= EXT2_LINK_MAX)
424 ext2_inc_count(old_inode);
425 err = ext2_add_link(new_dentry, old_inode);
427 ext2_dec_count(old_inode);
431 ext2_inc_count(new_dir);
434 ext2_delete_entry (old_de, old_page);
435 ext2_dec_count(old_inode);
438 ext2_set_link(old_inode, dir_de, dir_page, new_dir);
439 ext2_dec_count(old_dir);
447 page_cache_release(dir_page);
451 page_cache_release(old_page);
456 struct inode_operations obdfs_dir_inode_operations = {
457 create: obdfs_create,
458 lookup: obdfs_lookup,
460 unlink: obdfs_unlink,
461 symlink: obdfs_symlink,
465 rename: obdfs_rename,
466 setattr: obdfs_setattr