Commit | Line | Data |
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b2441318 | 1 | // SPDX-License-Identifier: GPL-2.0 |
1da177e4 LT |
2 | /* |
3 | * linux/fs/sysv/namei.c | |
4 | * | |
5 | * minix/namei.c | |
6 | * Copyright (C) 1991, 1992 Linus Torvalds | |
7 | * | |
8 | * coh/namei.c | |
9 | * Copyright (C) 1993 Pascal Haible, Bruno Haible | |
10 | * | |
11 | * sysv/namei.c | |
12 | * Copyright (C) 1993 Bruno Haible | |
13 | * Copyright (C) 1997, 1998 Krzysztof G. Baranowski | |
14 | */ | |
15 | ||
16 | #include <linux/pagemap.h> | |
1da177e4 LT |
17 | #include "sysv.h" |
18 | ||
1da177e4 LT |
19 | static int add_nondir(struct dentry *dentry, struct inode *inode) |
20 | { | |
21 | int err = sysv_add_link(dentry, inode); | |
22 | if (!err) { | |
23 | d_instantiate(dentry, inode); | |
24 | return 0; | |
25 | } | |
4e907c3d | 26 | inode_dec_link_count(inode); |
1da177e4 LT |
27 | iput(inode); |
28 | return err; | |
29 | } | |
30 | ||
00cd8dd3 | 31 | static struct dentry *sysv_lookup(struct inode * dir, struct dentry * dentry, unsigned int flags) |
1da177e4 LT |
32 | { |
33 | struct inode * inode = NULL; | |
34 | ino_t ino; | |
35 | ||
1da177e4 LT |
36 | if (dentry->d_name.len > SYSV_NAMELEN) |
37 | return ERR_PTR(-ENAMETOOLONG); | |
38 | ino = sysv_inode_by_name(dentry); | |
5bf35449 | 39 | if (ino) |
b8e1343f | 40 | inode = sysv_iget(dir->i_sb, ino); |
5bf35449 | 41 | return d_splice_alias(inode, dentry); |
1da177e4 LT |
42 | } |
43 | ||
5ebb29be | 44 | static int sysv_mknod(struct mnt_idmap *idmap, struct inode *dir, |
549c7297 | 45 | struct dentry *dentry, umode_t mode, dev_t rdev) |
1da177e4 LT |
46 | { |
47 | struct inode * inode; | |
48 | int err; | |
49 | ||
50 | if (!old_valid_dev(rdev)) | |
51 | return -EINVAL; | |
52 | ||
53 | inode = sysv_new_inode(dir, mode); | |
54 | err = PTR_ERR(inode); | |
55 | ||
56 | if (!IS_ERR(inode)) { | |
57 | sysv_set_inode(inode, rdev); | |
58 | mark_inode_dirty(inode); | |
59 | err = add_nondir(dentry, inode); | |
60 | } | |
61 | return err; | |
62 | } | |
63 | ||
6c960e68 | 64 | static int sysv_create(struct mnt_idmap *idmap, struct inode *dir, |
549c7297 | 65 | struct dentry *dentry, umode_t mode, bool excl) |
1da177e4 | 66 | { |
5ebb29be | 67 | return sysv_mknod(&nop_mnt_idmap, dir, dentry, mode, 0); |
1da177e4 LT |
68 | } |
69 | ||
7a77db95 | 70 | static int sysv_symlink(struct mnt_idmap *idmap, struct inode *dir, |
549c7297 | 71 | struct dentry *dentry, const char *symname) |
1da177e4 LT |
72 | { |
73 | int err = -ENAMETOOLONG; | |
74 | int l = strlen(symname)+1; | |
75 | struct inode * inode; | |
76 | ||
77 | if (l > dir->i_sb->s_blocksize) | |
78 | goto out; | |
79 | ||
80 | inode = sysv_new_inode(dir, S_IFLNK|0777); | |
81 | err = PTR_ERR(inode); | |
82 | if (IS_ERR(inode)) | |
83 | goto out; | |
84 | ||
85 | sysv_set_inode(inode, 0); | |
86 | err = page_symlink(inode, symname, l); | |
87 | if (err) | |
88 | goto out_fail; | |
89 | ||
90 | mark_inode_dirty(inode); | |
91 | err = add_nondir(dentry, inode); | |
92 | out: | |
93 | return err; | |
94 | ||
95 | out_fail: | |
4e907c3d | 96 | inode_dec_link_count(inode); |
1da177e4 LT |
97 | iput(inode); |
98 | goto out; | |
99 | } | |
100 | ||
101 | static int sysv_link(struct dentry * old_dentry, struct inode * dir, | |
102 | struct dentry * dentry) | |
103 | { | |
2b0143b5 | 104 | struct inode *inode = d_inode(old_dentry); |
1da177e4 | 105 | |
02027d42 | 106 | inode->i_ctime = current_time(inode); |
4e907c3d | 107 | inode_inc_link_count(inode); |
7de9c6ee | 108 | ihold(inode); |
1da177e4 LT |
109 | |
110 | return add_nondir(dentry, inode); | |
111 | } | |
112 | ||
c54bd91e | 113 | static int sysv_mkdir(struct mnt_idmap *idmap, struct inode *dir, |
549c7297 | 114 | struct dentry *dentry, umode_t mode) |
1da177e4 LT |
115 | { |
116 | struct inode * inode; | |
8de52778 | 117 | int err; |
1da177e4 | 118 | |
4e907c3d | 119 | inode_inc_link_count(dir); |
1da177e4 LT |
120 | |
121 | inode = sysv_new_inode(dir, S_IFDIR|mode); | |
122 | err = PTR_ERR(inode); | |
123 | if (IS_ERR(inode)) | |
124 | goto out_dir; | |
125 | ||
126 | sysv_set_inode(inode, 0); | |
127 | ||
4e907c3d | 128 | inode_inc_link_count(inode); |
1da177e4 LT |
129 | |
130 | err = sysv_make_empty(inode, dir); | |
131 | if (err) | |
132 | goto out_fail; | |
133 | ||
134 | err = sysv_add_link(dentry, inode); | |
135 | if (err) | |
136 | goto out_fail; | |
137 | ||
138 | d_instantiate(dentry, inode); | |
139 | out: | |
140 | return err; | |
141 | ||
142 | out_fail: | |
4e907c3d AD |
143 | inode_dec_link_count(inode); |
144 | inode_dec_link_count(inode); | |
1da177e4 LT |
145 | iput(inode); |
146 | out_dir: | |
4e907c3d | 147 | inode_dec_link_count(dir); |
1da177e4 LT |
148 | goto out; |
149 | } | |
150 | ||
151 | static int sysv_unlink(struct inode * dir, struct dentry * dentry) | |
152 | { | |
2b0143b5 | 153 | struct inode * inode = d_inode(dentry); |
1da177e4 LT |
154 | struct page * page; |
155 | struct sysv_dir_entry * de; | |
abb7c742 | 156 | int err; |
1da177e4 LT |
157 | |
158 | de = sysv_find_entry(dentry, &page); | |
159 | if (!de) | |
abb7c742 | 160 | return -ENOENT; |
1da177e4 | 161 | |
abb7c742 AV |
162 | err = sysv_delete_entry(de, page); |
163 | if (!err) { | |
164 | inode->i_ctime = dir->i_ctime; | |
165 | inode_dec_link_count(inode); | |
166 | } | |
167 | dir_put_page(page, de); | |
1da177e4 LT |
168 | return err; |
169 | } | |
170 | ||
171 | static int sysv_rmdir(struct inode * dir, struct dentry * dentry) | |
172 | { | |
2b0143b5 | 173 | struct inode *inode = d_inode(dentry); |
1da177e4 LT |
174 | int err = -ENOTEMPTY; |
175 | ||
176 | if (sysv_empty_dir(inode)) { | |
177 | err = sysv_unlink(dir, dentry); | |
178 | if (!err) { | |
179 | inode->i_size = 0; | |
4e907c3d AD |
180 | inode_dec_link_count(inode); |
181 | inode_dec_link_count(dir); | |
1da177e4 LT |
182 | } |
183 | } | |
184 | return err; | |
185 | } | |
186 | ||
187 | /* | |
188 | * Anybody can rename anything with this: the permission checks are left to the | |
189 | * higher-level routines. | |
190 | */ | |
e18275ae | 191 | static int sysv_rename(struct mnt_idmap *idmap, struct inode *old_dir, |
549c7297 CB |
192 | struct dentry *old_dentry, struct inode *new_dir, |
193 | struct dentry *new_dentry, unsigned int flags) | |
1da177e4 | 194 | { |
2b0143b5 DH |
195 | struct inode * old_inode = d_inode(old_dentry); |
196 | struct inode * new_inode = d_inode(new_dentry); | |
1da177e4 LT |
197 | struct page * dir_page = NULL; |
198 | struct sysv_dir_entry * dir_de = NULL; | |
199 | struct page * old_page; | |
200 | struct sysv_dir_entry * old_de; | |
201 | int err = -ENOENT; | |
202 | ||
f03b8ad8 MS |
203 | if (flags & ~RENAME_NOREPLACE) |
204 | return -EINVAL; | |
205 | ||
1da177e4 LT |
206 | old_de = sysv_find_entry(old_dentry, &old_page); |
207 | if (!old_de) | |
208 | goto out; | |
209 | ||
210 | if (S_ISDIR(old_inode->i_mode)) { | |
211 | err = -EIO; | |
212 | dir_de = sysv_dotdot(old_inode, &dir_page); | |
213 | if (!dir_de) | |
214 | goto out_old; | |
215 | } | |
216 | ||
217 | if (new_inode) { | |
218 | struct page * new_page; | |
219 | struct sysv_dir_entry * new_de; | |
220 | ||
221 | err = -ENOTEMPTY; | |
222 | if (dir_de && !sysv_empty_dir(new_inode)) | |
223 | goto out_dir; | |
224 | ||
225 | err = -ENOENT; | |
226 | new_de = sysv_find_entry(new_dentry, &new_page); | |
227 | if (!new_de) | |
228 | goto out_dir; | |
abb7c742 AV |
229 | err = sysv_set_link(new_de, new_page, old_inode); |
230 | dir_put_page(new_page, new_de); | |
231 | if (err) | |
232 | goto out_dir; | |
02027d42 | 233 | new_inode->i_ctime = current_time(new_inode); |
1da177e4 | 234 | if (dir_de) |
9a53c3a7 | 235 | drop_nlink(new_inode); |
4e907c3d | 236 | inode_dec_link_count(new_inode); |
1da177e4 | 237 | } else { |
1da177e4 | 238 | err = sysv_add_link(new_dentry, old_inode); |
4787d45f | 239 | if (err) |
1da177e4 | 240 | goto out_dir; |
1da177e4 | 241 | if (dir_de) |
4e907c3d | 242 | inode_inc_link_count(new_dir); |
1da177e4 LT |
243 | } |
244 | ||
abb7c742 AV |
245 | err = sysv_delete_entry(old_de, old_page); |
246 | if (err) | |
247 | goto out_dir; | |
248 | ||
4787d45f | 249 | mark_inode_dirty(old_inode); |
1da177e4 LT |
250 | |
251 | if (dir_de) { | |
abb7c742 AV |
252 | err = sysv_set_link(dir_de, dir_page, new_dir); |
253 | if (!err) | |
254 | inode_dec_link_count(old_dir); | |
1da177e4 | 255 | } |
1da177e4 LT |
256 | |
257 | out_dir: | |
c26ddc49 | 258 | if (dir_de) |
83005276 | 259 | dir_put_page(dir_page, dir_de); |
1da177e4 | 260 | out_old: |
83005276 | 261 | dir_put_page(old_page, old_de); |
1da177e4 LT |
262 | out: |
263 | return err; | |
264 | } | |
265 | ||
266 | /* | |
267 | * directories can handle most operations... | |
268 | */ | |
c5ef1c42 | 269 | const struct inode_operations sysv_dir_inode_operations = { |
1da177e4 LT |
270 | .create = sysv_create, |
271 | .lookup = sysv_lookup, | |
272 | .link = sysv_link, | |
273 | .unlink = sysv_unlink, | |
274 | .symlink = sysv_symlink, | |
275 | .mkdir = sysv_mkdir, | |
276 | .rmdir = sysv_rmdir, | |
277 | .mknod = sysv_mknod, | |
278 | .rename = sysv_rename, | |
279 | .getattr = sysv_getattr, | |
280 | }; |