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1/*
2 * linux/fs/ufs/namei.c
3 *
4 * Migration to usage of "page cache" on May 2006 by
5 * Evgeniy Dushistov <dushistov@mail.ru> based on ext2 code base.
6 *
7 * Copyright (C) 1998
8 * Daniel Pirkl <daniel.pirkl@email.cz>
9 * Charles University, Faculty of Mathematics and Physics
10 *
11 * from
12 *
13 * linux/fs/ext2/namei.c
14 *
15 * Copyright (C) 1992, 1993, 1994, 1995
16 * Remy Card (card@masi.ibp.fr)
17 * Laboratoire MASI - Institut Blaise Pascal
18 * Universite Pierre et Marie Curie (Paris VI)
19 *
20 * from
21 *
22 * linux/fs/minix/namei.c
23 *
24 * Copyright (C) 1991, 1992 Linus Torvalds
25 *
26 * Big-endian to little-endian byte-swapping/bitmaps by
27 * David S. Miller (davem@caip.rutgers.edu), 1995
28 */
29
30#include <linux/time.h>
31#include <linux/fs.h>
32
33#include "ufs_fs.h"
34#include "ufs.h"
35#include "util.h"
36
37static inline int ufs_add_nondir(struct dentry *dentry, struct inode *inode)
38{
39 int err = ufs_add_link(dentry, inode);
40 if (!err) {
41 d_instantiate(dentry, inode);
42 return 0;
43 }
44 inode_dec_link_count(inode);
45 iput(inode);
46 return err;
47}
48
49static struct dentry *ufs_lookup(struct inode * dir, struct dentry *dentry, struct nameidata *nd)
50{
51 struct inode * inode = NULL;
52 ino_t ino;
53
54 if (dentry->d_name.len > UFS_MAXNAMLEN)
55 return ERR_PTR(-ENAMETOOLONG);
56
57 lock_ufs(dir->i_sb);
58 ino = ufs_inode_by_name(dir, &dentry->d_name);
59 if (ino)
60 inode = ufs_iget(dir->i_sb, ino);
61 unlock_ufs(dir->i_sb);
62 return d_splice_alias(inode, dentry);
63}
64
65/*
66 * By the time this is called, we already have created
67 * the directory cache entry for the new file, but it
68 * is so far negative - it has no inode.
69 *
70 * If the create succeeds, we fill in the inode information
71 * with d_instantiate().
72 */
73static int ufs_create (struct inode * dir, struct dentry * dentry, umode_t mode,
74 struct nameidata *nd)
75{
76 struct inode *inode;
77 int err;
78
79 UFSD("BEGIN\n");
80
81 inode = ufs_new_inode(dir, mode);
82 err = PTR_ERR(inode);
83
84 if (!IS_ERR(inode)) {
85 inode->i_op = &ufs_file_inode_operations;
86 inode->i_fop = &ufs_file_operations;
87 inode->i_mapping->a_ops = &ufs_aops;
88 mark_inode_dirty(inode);
89 lock_ufs(dir->i_sb);
90 err = ufs_add_nondir(dentry, inode);
91 unlock_ufs(dir->i_sb);
92 }
93 UFSD("END: err=%d\n", err);
94 return err;
95}
96
97static int ufs_mknod(struct inode *dir, struct dentry *dentry, umode_t mode, dev_t rdev)
98{
99 struct inode *inode;
100 int err;
101
102 if (!old_valid_dev(rdev))
103 return -EINVAL;
104
105 inode = ufs_new_inode(dir, mode);
106 err = PTR_ERR(inode);
107 if (!IS_ERR(inode)) {
108 init_special_inode(inode, mode, rdev);
109 ufs_set_inode_dev(inode->i_sb, UFS_I(inode), rdev);
110 mark_inode_dirty(inode);
111 lock_ufs(dir->i_sb);
112 err = ufs_add_nondir(dentry, inode);
113 unlock_ufs(dir->i_sb);
114 }
115 return err;
116}
117
118static int ufs_symlink (struct inode * dir, struct dentry * dentry,
119 const char * symname)
120{
121 struct super_block * sb = dir->i_sb;
122 int err = -ENAMETOOLONG;
123 unsigned l = strlen(symname)+1;
124 struct inode * inode;
125
126 if (l > sb->s_blocksize)
127 goto out_notlocked;
128
129 lock_ufs(dir->i_sb);
130 inode = ufs_new_inode(dir, S_IFLNK | S_IRWXUGO);
131 err = PTR_ERR(inode);
132 if (IS_ERR(inode))
133 goto out;
134
135 if (l > UFS_SB(sb)->s_uspi->s_maxsymlinklen) {
136 /* slow symlink */
137 inode->i_op = &ufs_symlink_inode_operations;
138 inode->i_mapping->a_ops = &ufs_aops;
139 err = page_symlink(inode, symname, l);
140 if (err)
141 goto out_fail;
142 } else {
143 /* fast symlink */
144 inode->i_op = &ufs_fast_symlink_inode_operations;
145 memcpy(UFS_I(inode)->i_u1.i_symlink, symname, l);
146 inode->i_size = l-1;
147 }
148 mark_inode_dirty(inode);
149
150 err = ufs_add_nondir(dentry, inode);
151out:
152 unlock_ufs(dir->i_sb);
153out_notlocked:
154 return err;
155
156out_fail:
157 inode_dec_link_count(inode);
158 iput(inode);
159 goto out;
160}
161
162static int ufs_link (struct dentry * old_dentry, struct inode * dir,
163 struct dentry *dentry)
164{
165 struct inode *inode = old_dentry->d_inode;
166 int error;
167
168 lock_ufs(dir->i_sb);
169
170 inode->i_ctime = CURRENT_TIME_SEC;
171 inode_inc_link_count(inode);
172 ihold(inode);
173
174 error = ufs_add_nondir(dentry, inode);
175 unlock_ufs(dir->i_sb);
176 return error;
177}
178
179static int ufs_mkdir(struct inode * dir, struct dentry * dentry, umode_t mode)
180{
181 struct inode * inode;
182 int err;
183
184 lock_ufs(dir->i_sb);
185 inode_inc_link_count(dir);
186
187 inode = ufs_new_inode(dir, S_IFDIR|mode);
188 err = PTR_ERR(inode);
189 if (IS_ERR(inode))
190 goto out_dir;
191
192 inode->i_op = &ufs_dir_inode_operations;
193 inode->i_fop = &ufs_dir_operations;
194 inode->i_mapping->a_ops = &ufs_aops;
195
196 inode_inc_link_count(inode);
197
198 err = ufs_make_empty(inode, dir);
199 if (err)
200 goto out_fail;
201
202 err = ufs_add_link(dentry, inode);
203 if (err)
204 goto out_fail;
205 unlock_ufs(dir->i_sb);
206
207 d_instantiate(dentry, inode);
208out:
209 return err;
210
211out_fail:
212 inode_dec_link_count(inode);
213 inode_dec_link_count(inode);
214 iput (inode);
215out_dir:
216 inode_dec_link_count(dir);
217 unlock_ufs(dir->i_sb);
218 goto out;
219}
220
221static int ufs_unlink(struct inode *dir, struct dentry *dentry)
222{
223 struct inode * inode = dentry->d_inode;
224 struct ufs_dir_entry *de;
225 struct page *page;
226 int err = -ENOENT;
227
228 de = ufs_find_entry(dir, &dentry->d_name, &page);
229 if (!de)
230 goto out;
231
232 err = ufs_delete_entry(dir, de, page);
233 if (err)
234 goto out;
235
236 inode->i_ctime = dir->i_ctime;
237 inode_dec_link_count(inode);
238 err = 0;
239out:
240 return err;
241}
242
243static int ufs_rmdir (struct inode * dir, struct dentry *dentry)
244{
245 struct inode * inode = dentry->d_inode;
246 int err= -ENOTEMPTY;
247
248 lock_ufs(dir->i_sb);
249 if (ufs_empty_dir (inode)) {
250 err = ufs_unlink(dir, dentry);
251 if (!err) {
252 inode->i_size = 0;
253 inode_dec_link_count(inode);
254 inode_dec_link_count(dir);
255 }
256 }
257 unlock_ufs(dir->i_sb);
258 return err;
259}
260
261static int ufs_rename(struct inode *old_dir, struct dentry *old_dentry,
262 struct inode *new_dir, struct dentry *new_dentry)
263{
264 struct inode *old_inode = old_dentry->d_inode;
265 struct inode *new_inode = new_dentry->d_inode;
266 struct page *dir_page = NULL;
267 struct ufs_dir_entry * dir_de = NULL;
268 struct page *old_page;
269 struct ufs_dir_entry *old_de;
270 int err = -ENOENT;
271
272 old_de = ufs_find_entry(old_dir, &old_dentry->d_name, &old_page);
273 if (!old_de)
274 goto out;
275
276 if (S_ISDIR(old_inode->i_mode)) {
277 err = -EIO;
278 dir_de = ufs_dotdot(old_inode, &dir_page);
279 if (!dir_de)
280 goto out_old;
281 }
282
283 if (new_inode) {
284 struct page *new_page;
285 struct ufs_dir_entry *new_de;
286
287 err = -ENOTEMPTY;
288 if (dir_de && !ufs_empty_dir(new_inode))
289 goto out_dir;
290
291 err = -ENOENT;
292 new_de = ufs_find_entry(new_dir, &new_dentry->d_name, &new_page);
293 if (!new_de)
294 goto out_dir;
295 ufs_set_link(new_dir, new_de, new_page, old_inode);
296 new_inode->i_ctime = CURRENT_TIME_SEC;
297 if (dir_de)
298 drop_nlink(new_inode);
299 inode_dec_link_count(new_inode);
300 } else {
301 err = ufs_add_link(new_dentry, old_inode);
302 if (err)
303 goto out_dir;
304 if (dir_de)
305 inode_inc_link_count(new_dir);
306 }
307
308 /*
309 * Like most other Unix systems, set the ctime for inodes on a
310 * rename.
311 */
312 old_inode->i_ctime = CURRENT_TIME_SEC;
313
314 ufs_delete_entry(old_dir, old_de, old_page);
315 mark_inode_dirty(old_inode);
316
317 if (dir_de) {
318 ufs_set_link(old_inode, dir_de, dir_page, new_dir);
319 inode_dec_link_count(old_dir);
320 }
321 return 0;
322
323
324out_dir:
325 if (dir_de) {
326 kunmap(dir_page);
327 page_cache_release(dir_page);
328 }
329out_old:
330 kunmap(old_page);
331 page_cache_release(old_page);
332out:
333 return err;
334}
335
336const struct inode_operations ufs_dir_inode_operations = {
337 .create = ufs_create,
338 .lookup = ufs_lookup,
339 .link = ufs_link,
340 .unlink = ufs_unlink,
341 .symlink = ufs_symlink,
342 .mkdir = ufs_mkdir,
343 .rmdir = ufs_rmdir,
344 .mknod = ufs_mknod,
345 .rename = ufs_rename,
346};