1 | // SPDX-License-Identifier: GPL-2.0 |
2 | /* |
3 | * linux/fs/ufs/namei.c |
4 | * |
5 | * Migration to usage of "page cache" on May 2006 by |
6 | * Evgeniy Dushistov <dushistov@mail.ru> based on ext2 code base. |
7 | * |
8 | * Copyright (C) 1998 |
9 | * Daniel Pirkl <daniel.pirkl@email.cz> |
10 | * Charles University, Faculty of Mathematics and Physics |
11 | * |
12 | * from |
13 | * |
14 | * linux/fs/ext2/namei.c |
15 | * |
16 | * Copyright (C) 1992, 1993, 1994, 1995 |
17 | * Remy Card (card@masi.ibp.fr) |
18 | * Laboratoire MASI - Institut Blaise Pascal |
19 | * Universite Pierre et Marie Curie (Paris VI) |
20 | * |
21 | * from |
22 | * |
23 | * linux/fs/minix/namei.c |
24 | * |
25 | * Copyright (C) 1991, 1992 Linus Torvalds |
26 | * |
27 | * Big-endian to little-endian byte-swapping/bitmaps by |
28 | * David S. Miller (davem@caip.rutgers.edu), 1995 |
29 | */ |
30 | |
31 | #include <linux/time.h> |
32 | #include <linux/fs.h> |
33 | |
34 | #include "ufs_fs.h" |
35 | #include "ufs.h" |
36 | #include "util.h" |
37 | |
38 | static inline int ufs_add_nondir(struct dentry *dentry, struct inode *inode) |
39 | { |
40 | int err = ufs_add_link(dentry, inode); |
41 | if (!err) { |
42 | d_instantiate_new(dentry, inode); |
43 | return 0; |
44 | } |
45 | inode_dec_link_count(inode); |
46 | discard_new_inode(inode); |
47 | return err; |
48 | } |
49 | |
50 | static struct dentry *ufs_lookup(struct inode * dir, struct dentry *dentry, unsigned int flags) |
51 | { |
52 | struct inode * inode = NULL; |
53 | ino_t ino; |
54 | |
55 | if (dentry->d_name.len > UFS_MAXNAMLEN) |
56 | return ERR_PTR(error: -ENAMETOOLONG); |
57 | |
58 | ino = ufs_inode_by_name(dir, &dentry->d_name); |
59 | if (ino) |
60 | inode = ufs_iget(dir->i_sb, ino); |
61 | return d_splice_alias(inode, dentry); |
62 | } |
63 | |
64 | /* |
65 | * By the time this is called, we already have created |
66 | * the directory cache entry for the new file, but it |
67 | * is so far negative - it has no inode. |
68 | * |
69 | * If the create succeeds, we fill in the inode information |
70 | * with d_instantiate(). |
71 | */ |
72 | static int ufs_create (struct mnt_idmap * idmap, |
73 | struct inode * dir, struct dentry * dentry, umode_t mode, |
74 | bool excl) |
75 | { |
76 | struct inode *inode; |
77 | |
78 | inode = ufs_new_inode(dir, mode); |
79 | if (IS_ERR(ptr: inode)) |
80 | return PTR_ERR(ptr: inode); |
81 | |
82 | inode->i_op = &ufs_file_inode_operations; |
83 | inode->i_fop = &ufs_file_operations; |
84 | inode->i_mapping->a_ops = &ufs_aops; |
85 | mark_inode_dirty(inode); |
86 | return ufs_add_nondir(dentry, inode); |
87 | } |
88 | |
89 | static int ufs_mknod(struct mnt_idmap *idmap, struct inode *dir, |
90 | struct dentry *dentry, umode_t mode, dev_t rdev) |
91 | { |
92 | struct inode *inode; |
93 | int err; |
94 | |
95 | if (!old_valid_dev(dev: rdev)) |
96 | return -EINVAL; |
97 | |
98 | inode = ufs_new_inode(dir, mode); |
99 | err = PTR_ERR(ptr: inode); |
100 | if (!IS_ERR(ptr: inode)) { |
101 | init_special_inode(inode, mode, rdev); |
102 | ufs_set_inode_dev(inode->i_sb, UFS_I(inode), rdev); |
103 | mark_inode_dirty(inode); |
104 | err = ufs_add_nondir(dentry, inode); |
105 | } |
106 | return err; |
107 | } |
108 | |
109 | static int ufs_symlink (struct mnt_idmap * idmap, struct inode * dir, |
110 | struct dentry * dentry, const char * symname) |
111 | { |
112 | struct super_block * sb = dir->i_sb; |
113 | int err; |
114 | unsigned l = strlen(symname)+1; |
115 | struct inode * inode; |
116 | |
117 | if (l > sb->s_blocksize) |
118 | return -ENAMETOOLONG; |
119 | |
120 | inode = ufs_new_inode(dir, S_IFLNK | S_IRWXUGO); |
121 | err = PTR_ERR(ptr: inode); |
122 | if (IS_ERR(ptr: inode)) |
123 | return err; |
124 | |
125 | if (l > UFS_SB(sb)->s_uspi->s_maxsymlinklen) { |
126 | /* slow symlink */ |
127 | inode->i_op = &page_symlink_inode_operations; |
128 | inode_nohighmem(inode); |
129 | inode->i_mapping->a_ops = &ufs_aops; |
130 | err = page_symlink(inode, symname, len: l); |
131 | if (err) |
132 | goto out_fail; |
133 | } else { |
134 | /* fast symlink */ |
135 | inode->i_op = &simple_symlink_inode_operations; |
136 | inode->i_link = (char *)UFS_I(inode)->i_u1.i_symlink; |
137 | memcpy(inode->i_link, symname, l); |
138 | inode->i_size = l-1; |
139 | } |
140 | mark_inode_dirty(inode); |
141 | |
142 | return ufs_add_nondir(dentry, inode); |
143 | |
144 | out_fail: |
145 | inode_dec_link_count(inode); |
146 | discard_new_inode(inode); |
147 | return err; |
148 | } |
149 | |
150 | static int ufs_link (struct dentry * old_dentry, struct inode * dir, |
151 | struct dentry *dentry) |
152 | { |
153 | struct inode *inode = d_inode(dentry: old_dentry); |
154 | int error; |
155 | |
156 | inode_set_ctime_current(inode); |
157 | inode_inc_link_count(inode); |
158 | ihold(inode); |
159 | |
160 | error = ufs_add_link(dentry, inode); |
161 | if (error) { |
162 | inode_dec_link_count(inode); |
163 | iput(inode); |
164 | } else |
165 | d_instantiate(dentry, inode); |
166 | return error; |
167 | } |
168 | |
169 | static int ufs_mkdir(struct mnt_idmap * idmap, struct inode * dir, |
170 | struct dentry * dentry, umode_t mode) |
171 | { |
172 | struct inode * inode; |
173 | int err; |
174 | |
175 | inode_inc_link_count(inode: dir); |
176 | |
177 | inode = ufs_new_inode(dir, S_IFDIR|mode); |
178 | err = PTR_ERR(ptr: inode); |
179 | if (IS_ERR(ptr: inode)) |
180 | goto out_dir; |
181 | |
182 | inode->i_op = &ufs_dir_inode_operations; |
183 | inode->i_fop = &ufs_dir_operations; |
184 | inode->i_mapping->a_ops = &ufs_aops; |
185 | |
186 | inode_inc_link_count(inode); |
187 | |
188 | err = ufs_make_empty(inode, dir); |
189 | if (err) |
190 | goto out_fail; |
191 | |
192 | err = ufs_add_link(dentry, inode); |
193 | if (err) |
194 | goto out_fail; |
195 | |
196 | d_instantiate_new(dentry, inode); |
197 | return 0; |
198 | |
199 | out_fail: |
200 | inode_dec_link_count(inode); |
201 | inode_dec_link_count(inode); |
202 | discard_new_inode(inode); |
203 | out_dir: |
204 | inode_dec_link_count(inode: dir); |
205 | return err; |
206 | } |
207 | |
208 | static int ufs_unlink(struct inode *dir, struct dentry *dentry) |
209 | { |
210 | struct inode * inode = d_inode(dentry); |
211 | struct ufs_dir_entry *de; |
212 | struct page *page; |
213 | int err = -ENOENT; |
214 | |
215 | de = ufs_find_entry(dir, &dentry->d_name, &page); |
216 | if (!de) |
217 | goto out; |
218 | |
219 | err = ufs_delete_entry(dir, de, page); |
220 | if (err) |
221 | goto out; |
222 | |
223 | inode_set_ctime_to_ts(inode, ts: inode_get_ctime(inode: dir)); |
224 | inode_dec_link_count(inode); |
225 | err = 0; |
226 | out: |
227 | return err; |
228 | } |
229 | |
230 | static int ufs_rmdir (struct inode * dir, struct dentry *dentry) |
231 | { |
232 | struct inode * inode = d_inode(dentry); |
233 | int err= -ENOTEMPTY; |
234 | |
235 | if (ufs_empty_dir (inode)) { |
236 | err = ufs_unlink(dir, dentry); |
237 | if (!err) { |
238 | inode->i_size = 0; |
239 | inode_dec_link_count(inode); |
240 | inode_dec_link_count(inode: dir); |
241 | } |
242 | } |
243 | return err; |
244 | } |
245 | |
246 | static int ufs_rename(struct mnt_idmap *idmap, struct inode *old_dir, |
247 | struct dentry *old_dentry, struct inode *new_dir, |
248 | struct dentry *new_dentry, unsigned int flags) |
249 | { |
250 | struct inode *old_inode = d_inode(dentry: old_dentry); |
251 | struct inode *new_inode = d_inode(dentry: new_dentry); |
252 | struct page *dir_page = NULL; |
253 | struct ufs_dir_entry * dir_de = NULL; |
254 | struct page *old_page; |
255 | struct ufs_dir_entry *old_de; |
256 | int err = -ENOENT; |
257 | |
258 | if (flags & ~RENAME_NOREPLACE) |
259 | return -EINVAL; |
260 | |
261 | old_de = ufs_find_entry(old_dir, &old_dentry->d_name, &old_page); |
262 | if (!old_de) |
263 | goto out; |
264 | |
265 | if (S_ISDIR(old_inode->i_mode)) { |
266 | err = -EIO; |
267 | dir_de = ufs_dotdot(old_inode, &dir_page); |
268 | if (!dir_de) |
269 | goto out_old; |
270 | } |
271 | |
272 | if (new_inode) { |
273 | struct page *new_page; |
274 | struct ufs_dir_entry *new_de; |
275 | |
276 | err = -ENOTEMPTY; |
277 | if (dir_de && !ufs_empty_dir(new_inode)) |
278 | goto out_dir; |
279 | |
280 | err = -ENOENT; |
281 | new_de = ufs_find_entry(new_dir, &new_dentry->d_name, &new_page); |
282 | if (!new_de) |
283 | goto out_dir; |
284 | ufs_set_link(dir: new_dir, de: new_de, page: new_page, inode: old_inode, update_times: 1); |
285 | inode_set_ctime_current(inode: new_inode); |
286 | if (dir_de) |
287 | drop_nlink(inode: new_inode); |
288 | inode_dec_link_count(inode: new_inode); |
289 | } else { |
290 | err = ufs_add_link(new_dentry, old_inode); |
291 | if (err) |
292 | goto out_dir; |
293 | if (dir_de) |
294 | inode_inc_link_count(inode: new_dir); |
295 | } |
296 | |
297 | /* |
298 | * Like most other Unix systems, set the ctime for inodes on a |
299 | * rename. |
300 | */ |
301 | inode_set_ctime_current(inode: old_inode); |
302 | |
303 | ufs_delete_entry(old_dir, old_de, old_page); |
304 | mark_inode_dirty(inode: old_inode); |
305 | |
306 | if (dir_de) { |
307 | if (old_dir != new_dir) |
308 | ufs_set_link(dir: old_inode, de: dir_de, page: dir_page, inode: new_dir, update_times: 0); |
309 | else { |
310 | kunmap(page: dir_page); |
311 | put_page(page: dir_page); |
312 | } |
313 | inode_dec_link_count(inode: old_dir); |
314 | } |
315 | return 0; |
316 | |
317 | |
318 | out_dir: |
319 | if (dir_de) { |
320 | kunmap(page: dir_page); |
321 | put_page(page: dir_page); |
322 | } |
323 | out_old: |
324 | kunmap(page: old_page); |
325 | put_page(page: old_page); |
326 | out: |
327 | return err; |
328 | } |
329 | |
330 | const struct inode_operations ufs_dir_inode_operations = { |
331 | .create = ufs_create, |
332 | .lookup = ufs_lookup, |
333 | .link = ufs_link, |
334 | .unlink = ufs_unlink, |
335 | .symlink = ufs_symlink, |
336 | .mkdir = ufs_mkdir, |
337 | .rmdir = ufs_rmdir, |
338 | .mknod = ufs_mknod, |
339 | .rename = ufs_rename, |
340 | }; |
341 | |