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 /* 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;
91 if (dentry->d_name.len > EXT2_NAME_LEN)
92 return ERR_PTR(-ENAMETOOLONG);
94 ino = ext2_inode_by_name(dir, dentry);
98 oa = obdo_fromid(IID(dir), ino, OBD_MD_FLNOTOBD | OBD_MD_FLBLOCKS);
100 printk(__FUNCTION__ ": obdo_fromid failed\n");
102 return ERR_PTR(-EACCES);
105 inode = iget4(dir->i_sb, ino, NULL, oa);
109 return ERR_PTR(-EACCES);
112 d_add(dentry, inode);
118 * NOTE! unlike strncmp, ext2_match returns 1 for success, 0 for failure.
120 * `len <= EXT2_NAME_LEN' is guaranteed by caller.
121 * `de != NULL' is guaranteed by caller.
123 static inline int ext2_match (int len, const char * const name,
124 struct ext2_dir_entry_2 * de)
126 if (len != de->name_len)
130 return !memcmp(name, de->name, len);
133 static struct inode *obdfs_new_inode(struct inode *dir, int mode)
140 if (IOPS(dir, create) == NULL) {
141 printk(KERN_ERR __FUNCTION__ ": no create method!\n");
143 return ERR_PTR(-EIO);
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 = IOPS(dir, create)(IID(dir), oa);
156 CDEBUG(D_INODE, "\n");
159 printk("new_inode - fatal: err %d\n", err);
164 CDEBUG(D_INODE, "\n");
166 inode = iget4(dir->i_sb, (ino_t)oa->o_id, NULL, oa);
167 CDEBUG(D_INODE, "\n");
171 printk("new_inode -fatal: %ld\n", (long)oa->o_id);
172 IOPS(dir, destroy)(IID(dir), oa);
174 return ERR_PTR(-EIO);
177 if (!list_empty(&inode->i_dentry)) {
178 printk("new_inode -fatal: aliases %ld, ct %d lnk %d\n",
180 atomic_read(&inode->i_count),
182 IOPS(dir, destroy)(IID(dir), oa);
185 return ERR_PTR(-EIO);
190 } /* obdfs_new_inode */
194 * By the time this is called, we already have created
195 * the directory cache entry for the new file, but it
196 * is so far negative - it has no inode.
198 * If the create succeeds, we fill in the inode information
199 * with d_instantiate().
201 static int obdfs_create (struct inode * dir, struct dentry * dentry, int mode)
203 struct inode * inode = obdfs_new_inode (dir, mode);
204 int err = PTR_ERR(inode);
205 if (!IS_ERR(inode)) {
206 inode->i_op = &obdfs_file_inode_operations;
207 inode->i_fop = &obdfs_file_operations;
208 inode->i_mapping->a_ops = &obdfs_aops;
209 err = ext2_add_nondir(dentry, inode);
215 static int obdfs_mknod (struct inode * dir, struct dentry *dentry, int mode, int rdev)
217 struct inode * inode = obdfs_new_inode (dir, mode);
218 int err = PTR_ERR(inode);
219 if (!IS_ERR(inode)) {
220 init_special_inode(inode, mode, rdev);
221 obdfs_change_inode(inode);
222 err = ext2_add_nondir(dentry, inode);
227 static int obdfs_symlink (struct inode * dir, struct dentry * dentry,
228 const char * symname)
230 struct super_block * sb = dir->i_sb;
231 int err = -ENAMETOOLONG;
232 unsigned l = strlen(symname)+1;
233 struct inode * inode;
234 struct obdfs_inode_info *oinfo;
236 if (l > sb->s_blocksize)
239 inode = obdfs_new_inode (dir, S_IFLNK | S_IRWXUGO);
240 err = PTR_ERR(inode);
244 oinfo = obdfs_i2info(inode);
245 if (l >= sizeof(oinfo->oi_inline)) {
247 inode->i_op = &page_symlink_inode_operations;
248 inode->i_mapping->a_ops = &obdfs_aops;
249 err = block_symlink(inode, symname, l);
254 inode->i_op = &obdfs_fast_symlink_inode_operations;
255 memcpy(oinfo->oi_inline, symname, l);
258 obdfs_change_inode(inode);
260 err = ext2_add_nondir(dentry, inode);
265 ext2_dec_count(inode);
272 static int obdfs_link (struct dentry * old_dentry, struct inode * dir,
273 struct dentry *dentry)
275 struct inode *inode = old_dentry->d_inode;
277 if (S_ISDIR(inode->i_mode))
280 if (inode->i_nlink >= EXT2_LINK_MAX)
283 inode->i_ctime = CURRENT_TIME;
284 ext2_inc_count(inode);
285 atomic_inc(&inode->i_count);
287 return ext2_add_nondir(dentry, inode);
291 static int obdfs_mkdir(struct inode * dir, struct dentry * dentry, int mode)
293 struct inode * inode;
297 if (dir->i_nlink >= EXT2_LINK_MAX)
302 inode = obdfs_new_inode (dir, S_IFDIR | mode);
303 err = PTR_ERR(inode);
307 inode->i_op = &obdfs_dir_inode_operations;
308 inode->i_fop = &obdfs_dir_operations;
309 inode->i_mapping->a_ops = &obdfs_aops;
311 ext2_inc_count(inode);
313 err = ext2_make_empty(inode, dir);
317 err = ext2_add_link(dentry, inode);
321 d_instantiate(dentry, inode);
327 ext2_dec_count(inode);
328 ext2_dec_count(inode);
337 static int obdfs_unlink(struct inode * dir, struct dentry *dentry)
339 struct inode * inode = dentry->d_inode;
340 struct ext2_dir_entry_2 * de;
344 de = ext2_find_entry (dir, dentry, &page);
348 err = ext2_delete_entry (de, page);
352 inode->i_ctime = dir->i_ctime;
353 ext2_dec_count(inode);
360 static int obdfs_rmdir (struct inode * dir, struct dentry *dentry)
362 struct inode * inode = dentry->d_inode;
363 int err = -ENOTEMPTY;
365 if (ext2_empty_dir(inode)) {
366 err = obdfs_unlink(dir, dentry);
369 ext2_dec_count(inode);
376 static int obdfs_rename (struct inode * old_dir, struct dentry * old_dentry,
377 struct inode * new_dir, struct dentry * new_dentry )
379 struct inode * old_inode = old_dentry->d_inode;
380 struct inode * new_inode = new_dentry->d_inode;
381 struct page * dir_page = NULL;
382 struct ext2_dir_entry_2 * dir_de = NULL;
383 struct page * old_page;
384 struct ext2_dir_entry_2 * old_de;
387 old_de = ext2_find_entry (old_dir, old_dentry, &old_page);
391 if (S_ISDIR(old_inode->i_mode)) {
393 dir_de = ext2_dotdot(old_inode, &dir_page);
399 struct page *new_page;
400 struct ext2_dir_entry_2 *new_de;
403 if (dir_de && !ext2_empty_dir (new_inode))
407 new_de = ext2_find_entry (new_dir, new_dentry, &new_page);
410 ext2_inc_count(old_inode);
411 ext2_set_link(new_dir, new_de, new_page, old_inode);
412 new_inode->i_ctime = CURRENT_TIME;
414 new_inode->i_nlink--;
415 ext2_dec_count(new_inode);
419 if (new_dir->i_nlink >= EXT2_LINK_MAX)
422 ext2_inc_count(old_inode);
423 err = ext2_add_link(new_dentry, old_inode);
425 ext2_dec_count(old_inode);
429 ext2_inc_count(new_dir);
432 ext2_delete_entry (old_de, old_page);
433 ext2_dec_count(old_inode);
436 ext2_set_link(old_inode, dir_de, dir_page, new_dir);
437 ext2_dec_count(old_dir);
445 page_cache_release(dir_page);
449 page_cache_release(old_page);
454 struct inode_operations obdfs_dir_inode_operations = {
455 create: obdfs_create,
456 lookup: obdfs_lookup,
458 unlink: obdfs_unlink,
459 symlink: obdfs_symlink,
463 rename: obdfs_rename,
464 setattr: obdfs_setattr