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 extern ino_t ext2_inode_by_name(struct inode * dir, struct dentry *dentry);
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 static inline void ext2_dec_count(struct inode *inode)
65 obdfs_change_inode(inode);
68 static inline int ext2_add_nondir(struct dentry *dentry, struct inode *inode)
70 int err = ext2_add_link(dentry, inode);
72 d_instantiate(dentry, inode);
75 ext2_dec_count(inode);
81 static struct dentry *obdfs_lookup(struct inode * dir, struct dentry *dentry)
86 if (dentry->d_name.len > EXT2_NAME_LEN)
87 return ERR_PTR(-ENAMETOOLONG);
89 ino = ext2_inode_by_name(dir, dentry);
92 inode = iget(dir->i_sb, ino);
94 return ERR_PTR(-EACCES);
102 * NOTE! unlike strncmp, ext2_match returns 1 for success, 0 for failure.
104 * `len <= EXT2_NAME_LEN' is guaranteed by caller.
105 * `de != NULL' is guaranteed by caller.
107 static inline int ext2_match (int len, const char * const name,
108 struct ext2_dir_entry_2 * de)
110 if (len != de->name_len)
114 return !memcmp(name, de->name, len);
117 static struct inode *obdfs_new_inode(struct inode *dir, int mode)
124 if (IOPS(dir, create) == NULL) {
125 printk(KERN_ERR __FUNCTION__ ": no create method!\n");
127 return ERR_PTR(-EIO);
132 return ERR_PTR(-ENOMEM);
135 /* Send a hint to the create method on the type of file to create */
137 oa->o_valid |= OBD_MD_FLMODE;
139 err = IOPS(dir, create)(IID(dir), oa);
142 printk("new_inode - fatal: err %d\n", err);
148 inode = iget(dir->i_sb, (ino_t)oa->o_id);
151 printk("new_inode -fatal: %ld\n", (long)oa->o_id);
152 IOPS(dir, destroy)(IID(dir), oa);
155 return ERR_PTR(-EIO);
158 if (!list_empty(&inode->i_dentry)) {
159 printk("new_inode -fatal: aliases %ld, ct %d lnk %d\n", (long)oa->o_id,
160 atomic_read(&inode->i_count), inode->i_nlink);
161 IOPS(dir, destroy)(IID(dir), oa);
165 return ERR_PTR(-EIO);
171 } /* obdfs_new_inode */
175 * By the time this is called, we already have created
176 * the directory cache entry for the new file, but it
177 * is so far negative - it has no inode.
179 * If the create succeeds, we fill in the inode information
180 * with d_instantiate().
182 static int obdfs_create (struct inode * dir, struct dentry * dentry, int mode)
184 struct inode * inode = obdfs_new_inode (dir, mode);
185 int err = PTR_ERR(inode);
186 if (!IS_ERR(inode)) {
187 inode->i_op = &obdfs_file_inode_operations;
188 inode->i_fop = &obdfs_file_operations;
189 inode->i_mapping->a_ops = &obdfs_aops;
190 obdfs_change_inode(inode);
191 err = ext2_add_nondir(dentry, inode);
197 static int obdfs_mknod (struct inode * dir, struct dentry *dentry, int mode, int rdev)
199 struct inode * inode = obdfs_new_inode (dir, mode);
200 int err = PTR_ERR(inode);
201 if (!IS_ERR(inode)) {
202 init_special_inode(inode, mode, rdev);
203 obdfs_change_inode(inode);
204 err = ext2_add_nondir(dentry, inode);
209 static int obdfs_symlink (struct inode * dir, struct dentry * dentry,
210 const char * symname)
212 struct super_block * sb = dir->i_sb;
213 int err = -ENAMETOOLONG;
214 unsigned l = strlen(symname)+1;
215 struct inode * inode;
216 struct obdfs_inode_info *oinfo;
218 if (l > sb->s_blocksize)
221 inode = obdfs_new_inode (dir, S_IFLNK | S_IRWXUGO);
222 err = PTR_ERR(inode);
226 oinfo = obdfs_i2info(inode);
227 if (l >= sizeof(oinfo->oi_inline)) {
229 inode->i_op = &page_symlink_inode_operations;
230 inode->i_mapping->a_ops = &obdfs_aops;
231 err = block_symlink(inode, symname, l);
236 inode->i_op = &obdfs_fast_symlink_inode_operations;
237 memcpy(oinfo->oi_inline, symname, l);
240 obdfs_change_inode(inode);
242 err = ext2_add_nondir(dentry, inode);
247 ext2_dec_count(inode);
254 static int obdfs_link (struct dentry * old_dentry, struct inode * dir,
255 struct dentry *dentry)
257 struct inode *inode = old_dentry->d_inode;
259 if (S_ISDIR(inode->i_mode))
262 if (inode->i_nlink >= EXT2_LINK_MAX)
265 inode->i_ctime = CURRENT_TIME;
266 ext2_inc_count(inode);
267 atomic_inc(&inode->i_count);
269 return ext2_add_nondir(dentry, inode);
273 static int obdfs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
275 struct inode * inode;
278 if (dir->i_nlink >= EXT2_LINK_MAX)
283 inode = obdfs_new_inode (dir, S_IFDIR | mode);
284 err = PTR_ERR(inode);
288 inode->i_op = &obdfs_dir_inode_operations;
289 inode->i_fop = &obdfs_dir_operations;
290 inode->i_mapping->a_ops = &obdfs_aops;
292 ext2_inc_count(inode);
294 err = ext2_make_empty(inode, dir);
298 err = ext2_add_link(dentry, inode);
302 d_instantiate(dentry, inode);
307 ext2_dec_count(inode);
308 ext2_dec_count(inode);
315 static int obdfs_unlink(struct inode * dir, struct dentry *dentry)
317 struct inode * inode = dentry->d_inode;
318 struct ext2_dir_entry_2 * de;
322 de = ext2_find_entry (dir, dentry, &page);
326 err = ext2_delete_entry (de, page);
330 inode->i_ctime = dir->i_ctime;
331 ext2_dec_count(inode);
338 static int obdfs_rmdir (struct inode * dir, struct dentry *dentry)
340 struct inode * inode = dentry->d_inode;
341 int err = -ENOTEMPTY;
343 if (ext2_empty_dir(inode)) {
344 err = obdfs_unlink(dir, dentry);
347 ext2_dec_count(inode);
354 static int obdfs_rename (struct inode * old_dir, struct dentry * old_dentry,
355 struct inode * new_dir, struct dentry * new_dentry )
357 struct inode * old_inode = old_dentry->d_inode;
358 struct inode * new_inode = new_dentry->d_inode;
359 struct page * dir_page = NULL;
360 struct ext2_dir_entry_2 * dir_de = NULL;
361 struct page * old_page;
362 struct ext2_dir_entry_2 * old_de;
365 old_de = ext2_find_entry (old_dir, old_dentry, &old_page);
369 if (S_ISDIR(old_inode->i_mode)) {
371 dir_de = ext2_dotdot(old_inode, &dir_page);
377 struct page *new_page;
378 struct ext2_dir_entry_2 *new_de;
381 if (dir_de && !ext2_empty_dir (new_inode))
385 new_de = ext2_find_entry (new_dir, new_dentry, &new_page);
388 ext2_inc_count(old_inode);
389 ext2_set_link(new_dir, new_de, new_page, old_inode);
390 new_inode->i_ctime = CURRENT_TIME;
392 new_inode->i_nlink--;
393 ext2_dec_count(new_inode);
397 if (new_dir->i_nlink >= EXT2_LINK_MAX)
400 ext2_inc_count(old_inode);
401 err = ext2_add_link(new_dentry, old_inode);
403 ext2_dec_count(old_inode);
407 ext2_inc_count(new_dir);
410 ext2_delete_entry (old_de, old_page);
411 ext2_dec_count(old_inode);
414 ext2_set_link(old_inode, dir_de, dir_page, new_dir);
415 ext2_dec_count(old_dir);
423 page_cache_release(dir_page);
427 page_cache_release(old_page);
432 struct inode_operations obdfs_dir_inode_operations = {
433 create: obdfs_create,
434 lookup: obdfs_lookup,
436 unlink: obdfs_unlink,
437 symlink: obdfs_symlink,
441 rename: obdfs_rename,
442 setattr: obdfs_setattr