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>
34 #define DEBUG_SUBSYSTEM S_OBDFS
36 #include <linux/obdfs.h>
37 #include <linux/lustre_lite.h>
38 extern struct address_space_operations obdfs_aops;
41 extern void obdfs_change_inode(struct inode *inode);
42 extern int obdfs_setattr(struct dentry *de, struct iattr *attr);
45 extern int ext2_add_link (struct dentry *dentry, struct inode *inode);
46 obd_id obdfs_inode_by_name(struct inode * dir, struct dentry *dentry, int *typ);
47 int ext2_make_empty(struct inode *inode, struct inode *parent);
48 struct ext2_dir_entry_2 * ext2_find_entry (struct inode * dir,
49 struct dentry *dentry, struct page ** res_page);
50 int ext2_delete_entry (struct ext2_dir_entry_2 * dir, struct page * page );
51 int ext2_empty_dir (struct inode * inode);
52 struct ext2_dir_entry_2 * ext2_dotdot (struct inode *dir, struct page **p);
53 void ext2_set_link(struct inode *dir, struct ext2_dir_entry_2 *de,
54 struct page *page, struct inode *inode);
57 * Couple of helper functions - make the code slightly cleaner.
59 static inline void ext2_inc_count(struct inode *inode)
62 obdfs_change_inode(inode);
65 /* postpone the disk update until the inode really goes away */
66 static inline void ext2_dec_count(struct inode *inode)
69 if (inode->i_nlink > 0)
70 obdfs_change_inode(inode);
73 static inline int ext2_add_nondir(struct dentry *dentry, struct inode *inode)
76 err = ext2_add_link(dentry, inode);
78 d_instantiate(dentry, inode);
81 ext2_dec_count(inode);
87 static struct dentry *obdfs_lookup(struct inode * dir, struct dentry *dentry)
90 struct inode * inode = NULL;
95 if (dentry->d_name.len > EXT2_NAME_LEN)
96 return ERR_PTR(-ENAMETOOLONG);
98 ino = obdfs_inode_by_name(dir, dentry, &type);
102 oa = obdo_fromid(IID(dir), ino, type,
103 (__u32)(OBD_MD_FLNOTOBD | OBD_MD_FLBLOCKS));
105 CERROR("obdo_fromid failed\n");
107 return ERR_PTR(-EACCES);
110 inode = iget4(dir->i_sb, (ino_t)ino, NULL, oa);
114 return ERR_PTR(-EACCES);
117 d_add(dentry, inode);
123 * NOTE! unlike strncmp, ext2_match returns 1 for success, 0 for failure.
125 * `len <= EXT2_NAME_LEN' is guaranteed by caller.
126 * `de != NULL' is guaranteed by caller.
128 static inline int ext2_match (int len, const char * const name,
129 struct ext2_dir_entry_2 * de)
131 if (len != de->name_len)
135 return !memcmp(name, de->name, len);
138 static struct inode *obdfs_new_inode(struct inode *dir, int mode)
148 return ERR_PTR(-ENOMEM);
151 /* Send a hint to the create method on the type of file to create */
153 oa->o_valid |= OBD_MD_FLMODE;
154 CDEBUG(D_INODE, "\n");
155 err = obd_create(IID(dir), oa, NULL);
156 CDEBUG(D_INODE, "\n");
159 CERROR("new_inode - fatal: err %d\n", err);
164 CDEBUG(D_INODE, "obdo mode %o\n", oa->o_mode);
166 inode = iget4(dir->i_sb, (ino_t)oa->o_id, NULL, oa);
167 CDEBUG(D_INODE, "\n");
170 CERROR("new_inode -fatal: %ld\n", (long)oa->o_id);
171 obd_destroy(IID(dir), oa, NULL);
174 return ERR_PTR(-EIO);
178 if (!list_empty(&inode->i_dentry)) {
179 CERROR("new_inode -fatal: aliases %ld, ct %d lnk %d\n",
181 atomic_read(&inode->i_count),
183 obd_destroy(IID(dir), oa, NULL);
186 return ERR_PTR(-EIO);
191 } /* obdfs_new_inode */
195 * By the time this is called, we already have created
196 * the directory cache entry for the new file, but it
197 * is so far negative - it has no inode.
199 * If the create succeeds, we fill in the inode information
200 * with d_instantiate().
202 static int obdfs_create (struct inode * dir, struct dentry * dentry, int mode)
204 struct inode * inode = obdfs_new_inode (dir, mode);
205 int err = PTR_ERR(inode);
206 if (!IS_ERR(inode)) {
207 inode->i_op = &obdfs_file_inode_operations;
208 inode->i_fop = &obdfs_file_operations;
209 inode->i_mapping->a_ops = &obdfs_aops;
210 err = ext2_add_nondir(dentry, inode);
216 static int obdfs_mknod (struct inode * dir, struct dentry *dentry, int mode, int rdev)
218 struct inode * inode = obdfs_new_inode (dir, mode);
219 int err = PTR_ERR(inode);
220 if (!IS_ERR(inode)) {
221 init_special_inode(inode, mode, rdev);
222 obdfs_change_inode(inode);
223 err = ext2_add_nondir(dentry, inode);
228 static int obdfs_symlink (struct inode * dir, struct dentry * dentry,
229 const char * symname)
231 struct super_block * sb = dir->i_sb;
232 int err = -ENAMETOOLONG;
233 unsigned l = strlen(symname)+1;
234 struct inode * inode;
235 struct obdfs_inode_info *oinfo;
237 if (l > sb->s_blocksize)
240 inode = obdfs_new_inode (dir, S_IFLNK | S_IRWXUGO);
241 err = PTR_ERR(inode);
245 oinfo = obdfs_i2info(inode);
246 if (l >= sizeof(oinfo->oi_inline)) {
248 inode->i_op = &page_symlink_inode_operations;
249 inode->i_mapping->a_ops = &obdfs_aops;
250 err = block_symlink(inode, symname, l);
255 inode->i_op = &obdfs_fast_symlink_inode_operations;
256 memcpy(oinfo->oi_inline, symname, l);
259 obdfs_change_inode(inode);
261 err = ext2_add_nondir(dentry, inode);
266 ext2_dec_count(inode);
273 static int obdfs_link (struct dentry * old_dentry, struct inode * dir,
274 struct dentry *dentry)
276 struct inode *inode = old_dentry->d_inode;
278 if (S_ISDIR(inode->i_mode))
281 if (inode->i_nlink >= EXT2_LINK_MAX)
284 inode->i_ctime = CURRENT_TIME;
285 ext2_inc_count(inode);
286 atomic_inc(&inode->i_count);
288 return ext2_add_nondir(dentry, inode);
292 static int obdfs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
294 struct inode * inode;
298 if (dir->i_nlink >= EXT2_LINK_MAX)
303 inode = obdfs_new_inode (dir, S_IFDIR | mode);
304 err = PTR_ERR(inode);
308 inode->i_op = &obdfs_dir_inode_operations;
309 inode->i_fop = &obdfs_dir_operations;
310 inode->i_mapping->a_ops = &obdfs_aops;
312 ext2_inc_count(inode);
314 err = ext2_make_empty(inode, dir);
318 err = ext2_add_link(dentry, inode);
322 d_instantiate(dentry, inode);
328 ext2_dec_count(inode);
329 ext2_dec_count(inode);
338 static int obdfs_unlink(struct inode * dir, struct dentry *dentry)
340 struct inode * inode = dentry->d_inode;
341 struct ext2_dir_entry_2 * de;
345 de = ext2_find_entry (dir, dentry, &page);
349 err = ext2_delete_entry (de, page);
353 inode->i_ctime = dir->i_ctime;
354 ext2_dec_count(inode);
361 static int obdfs_rmdir (struct inode * dir, struct dentry *dentry)
363 struct inode * inode = dentry->d_inode;
364 int err = -ENOTEMPTY;
366 if (ext2_empty_dir(inode)) {
367 err = obdfs_unlink(dir, dentry);
370 ext2_dec_count(inode);
377 static int obdfs_rename (struct inode * old_dir, struct dentry * old_dentry,
378 struct inode * new_dir, struct dentry * new_dentry )
380 struct inode * old_inode = old_dentry->d_inode;
381 struct inode * new_inode = new_dentry->d_inode;
382 struct page * dir_page = NULL;
383 struct ext2_dir_entry_2 * dir_de = NULL;
384 struct page * old_page;
385 struct ext2_dir_entry_2 * old_de;
388 old_de = ext2_find_entry (old_dir, old_dentry, &old_page);
392 if (S_ISDIR(old_inode->i_mode)) {
394 dir_de = ext2_dotdot(old_inode, &dir_page);
400 struct page *new_page;
401 struct ext2_dir_entry_2 *new_de;
404 if (dir_de && !ext2_empty_dir (new_inode))
408 new_de = ext2_find_entry (new_dir, new_dentry, &new_page);
411 ext2_inc_count(old_inode);
412 ext2_set_link(new_dir, new_de, new_page, old_inode);
413 new_inode->i_ctime = CURRENT_TIME;
415 new_inode->i_nlink--;
416 ext2_dec_count(new_inode);
420 if (new_dir->i_nlink >= EXT2_LINK_MAX)
423 ext2_inc_count(old_inode);
424 err = ext2_add_link(new_dentry, old_inode);
426 ext2_dec_count(old_inode);
430 ext2_inc_count(new_dir);
433 ext2_delete_entry (old_de, old_page);
434 ext2_dec_count(old_inode);
437 ext2_set_link(old_inode, dir_de, dir_page, new_dir);
438 ext2_dec_count(old_dir);
446 page_cache_release(dir_page);
450 page_cache_release(old_page);
455 struct inode_operations obdfs_dir_inode_operations = {
456 create: obdfs_create,
457 lookup: obdfs_lookup,
459 unlink: obdfs_unlink,
460 symlink: obdfs_symlink,
464 rename: obdfs_rename,
465 setattr: obdfs_setattr