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1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/minix/namei.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 */
7
8#include "minix.h"
9
10static int add_nondir(struct dentry *dentry, struct inode *inode)
11{
12 int err = minix_add_link(dentry, inode);
13 if (!err) {
14 d_instantiate(dentry, inode);
15 return 0;
16 }
17 inode_dec_link_count(inode);
18 iput(inode);
19 return err;
20}
21
22static struct dentry *minix_lookup(struct inode * dir, struct dentry *dentry, unsigned int flags)
23{
24 struct inode * inode = NULL;
25 ino_t ino;
26
27 if (dentry->d_name.len > minix_sb(dir->i_sb)->s_namelen)
28 return ERR_PTR(-ENAMETOOLONG);
29
30 ino = minix_inode_by_name(dentry);
31 if (ino)
32 inode = minix_iget(dir->i_sb, ino);
33 return d_splice_alias(inode, dentry);
34}
35
36static int minix_mknod(struct mnt_idmap *idmap, struct inode *dir,
37 struct dentry *dentry, umode_t mode, dev_t rdev)
38{
39 struct inode *inode;
40
41 if (!old_valid_dev(rdev))
42 return -EINVAL;
43
44 inode = minix_new_inode(dir, mode);
45 if (IS_ERR(inode))
46 return PTR_ERR(inode);
47
48 minix_set_inode(inode, rdev);
49 mark_inode_dirty(inode);
50 return add_nondir(dentry, inode);
51}
52
53static int minix_tmpfile(struct mnt_idmap *idmap, struct inode *dir,
54 struct file *file, umode_t mode)
55{
56 struct inode *inode = minix_new_inode(dir, mode);
57
58 if (IS_ERR(inode))
59 return finish_open_simple(file, PTR_ERR(inode));
60 minix_set_inode(inode, 0);
61 mark_inode_dirty(inode);
62 d_tmpfile(file, inode);
63 return finish_open_simple(file, 0);
64}
65
66static int minix_create(struct mnt_idmap *idmap, struct inode *dir,
67 struct dentry *dentry, umode_t mode, bool excl)
68{
69 return minix_mknod(&nop_mnt_idmap, dir, dentry, mode, 0);
70}
71
72static int minix_symlink(struct mnt_idmap *idmap, struct inode *dir,
73 struct dentry *dentry, const char *symname)
74{
75 int i = strlen(symname)+1;
76 struct inode * inode;
77 int err;
78
79 if (i > dir->i_sb->s_blocksize)
80 return -ENAMETOOLONG;
81
82 inode = minix_new_inode(dir, S_IFLNK | 0777);
83 if (IS_ERR(inode))
84 return PTR_ERR(inode);
85
86 minix_set_inode(inode, 0);
87 err = page_symlink(inode, symname, i);
88 if (unlikely(err)) {
89 inode_dec_link_count(inode);
90 iput(inode);
91 return err;
92 }
93 return add_nondir(dentry, inode);
94}
95
96static int minix_link(struct dentry * old_dentry, struct inode * dir,
97 struct dentry *dentry)
98{
99 struct inode *inode = d_inode(old_dentry);
100
101 inode_set_ctime_current(inode);
102 inode_inc_link_count(inode);
103 ihold(inode);
104 return add_nondir(dentry, inode);
105}
106
107static int minix_mkdir(struct mnt_idmap *idmap, struct inode *dir,
108 struct dentry *dentry, umode_t mode)
109{
110 struct inode * inode;
111 int err;
112
113 inode = minix_new_inode(dir, S_IFDIR | mode);
114 if (IS_ERR(inode))
115 return PTR_ERR(inode);
116
117 inode_inc_link_count(dir);
118 minix_set_inode(inode, 0);
119 inode_inc_link_count(inode);
120
121 err = minix_make_empty(inode, dir);
122 if (err)
123 goto out_fail;
124
125 err = minix_add_link(dentry, inode);
126 if (err)
127 goto out_fail;
128
129 d_instantiate(dentry, inode);
130out:
131 return err;
132
133out_fail:
134 inode_dec_link_count(inode);
135 inode_dec_link_count(inode);
136 iput(inode);
137 inode_dec_link_count(dir);
138 goto out;
139}
140
141static int minix_unlink(struct inode * dir, struct dentry *dentry)
142{
143 struct inode * inode = d_inode(dentry);
144 struct page * page;
145 struct minix_dir_entry * de;
146 int err;
147
148 de = minix_find_entry(dentry, &page);
149 if (!de)
150 return -ENOENT;
151 err = minix_delete_entry(de, page);
152 unmap_and_put_page(page, de);
153
154 if (err)
155 return err;
156 inode_set_ctime_to_ts(inode, inode_get_ctime(dir));
157 inode_dec_link_count(inode);
158 return 0;
159}
160
161static int minix_rmdir(struct inode * dir, struct dentry *dentry)
162{
163 struct inode * inode = d_inode(dentry);
164 int err = -ENOTEMPTY;
165
166 if (minix_empty_dir(inode)) {
167 err = minix_unlink(dir, dentry);
168 if (!err) {
169 inode_dec_link_count(dir);
170 inode_dec_link_count(inode);
171 }
172 }
173 return err;
174}
175
176static int minix_rename(struct mnt_idmap *idmap,
177 struct inode *old_dir, struct dentry *old_dentry,
178 struct inode *new_dir, struct dentry *new_dentry,
179 unsigned int flags)
180{
181 struct inode * old_inode = d_inode(old_dentry);
182 struct inode * new_inode = d_inode(new_dentry);
183 struct page * dir_page = NULL;
184 struct minix_dir_entry * dir_de = NULL;
185 struct page * old_page;
186 struct minix_dir_entry * old_de;
187 int err = -ENOENT;
188
189 if (flags & ~RENAME_NOREPLACE)
190 return -EINVAL;
191
192 old_de = minix_find_entry(old_dentry, &old_page);
193 if (!old_de)
194 goto out;
195
196 if (S_ISDIR(old_inode->i_mode)) {
197 err = -EIO;
198 dir_de = minix_dotdot(old_inode, &dir_page);
199 if (!dir_de)
200 goto out_old;
201 }
202
203 if (new_inode) {
204 struct page * new_page;
205 struct minix_dir_entry * new_de;
206
207 err = -ENOTEMPTY;
208 if (dir_de && !minix_empty_dir(new_inode))
209 goto out_dir;
210
211 err = -ENOENT;
212 new_de = minix_find_entry(new_dentry, &new_page);
213 if (!new_de)
214 goto out_dir;
215 err = minix_set_link(new_de, new_page, old_inode);
216 kunmap(new_page);
217 put_page(new_page);
218 if (err)
219 goto out_dir;
220 inode_set_ctime_current(new_inode);
221 if (dir_de)
222 drop_nlink(new_inode);
223 inode_dec_link_count(new_inode);
224 } else {
225 err = minix_add_link(new_dentry, old_inode);
226 if (err)
227 goto out_dir;
228 if (dir_de)
229 inode_inc_link_count(new_dir);
230 }
231
232 err = minix_delete_entry(old_de, old_page);
233 if (err)
234 goto out_dir;
235
236 mark_inode_dirty(old_inode);
237
238 if (dir_de) {
239 err = minix_set_link(dir_de, dir_page, new_dir);
240 if (!err)
241 inode_dec_link_count(old_dir);
242 }
243out_dir:
244 if (dir_de)
245 unmap_and_put_page(dir_page, dir_de);
246out_old:
247 unmap_and_put_page(old_page, old_de);
248out:
249 return err;
250}
251
252/*
253 * directories can handle most operations...
254 */
255const struct inode_operations minix_dir_inode_operations = {
256 .create = minix_create,
257 .lookup = minix_lookup,
258 .link = minix_link,
259 .unlink = minix_unlink,
260 .symlink = minix_symlink,
261 .mkdir = minix_mkdir,
262 .rmdir = minix_rmdir,
263 .mknod = minix_mknod,
264 .rename = minix_rename,
265 .getattr = minix_getattr,
266 .tmpfile = minix_tmpfile,
267};
1// SPDX-License-Identifier: GPL-2.0
2/*
3 * linux/fs/minix/namei.c
4 *
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 */
7
8#include "minix.h"
9
10static int add_nondir(struct dentry *dentry, struct inode *inode)
11{
12 int err = minix_add_link(dentry, inode);
13 if (!err) {
14 d_instantiate(dentry, inode);
15 return 0;
16 }
17 inode_dec_link_count(inode);
18 iput(inode);
19 return err;
20}
21
22static struct dentry *minix_lookup(struct inode * dir, struct dentry *dentry, unsigned int flags)
23{
24 struct inode * inode = NULL;
25 ino_t ino;
26
27 if (dentry->d_name.len > minix_sb(dir->i_sb)->s_namelen)
28 return ERR_PTR(-ENAMETOOLONG);
29
30 ino = minix_inode_by_name(dentry);
31 if (ino)
32 inode = minix_iget(dir->i_sb, ino);
33 return d_splice_alias(inode, dentry);
34}
35
36static int minix_mknod(struct user_namespace *mnt_userns, struct inode *dir,
37 struct dentry *dentry, umode_t mode, dev_t rdev)
38{
39 int error;
40 struct inode *inode;
41
42 if (!old_valid_dev(rdev))
43 return -EINVAL;
44
45 inode = minix_new_inode(dir, mode, &error);
46
47 if (inode) {
48 minix_set_inode(inode, rdev);
49 mark_inode_dirty(inode);
50 error = add_nondir(dentry, inode);
51 }
52 return error;
53}
54
55static int minix_tmpfile(struct user_namespace *mnt_userns, struct inode *dir,
56 struct file *file, umode_t mode)
57{
58 int error;
59 struct inode *inode = minix_new_inode(dir, mode, &error);
60 if (inode) {
61 minix_set_inode(inode, 0);
62 mark_inode_dirty(inode);
63 d_tmpfile(file, inode);
64 }
65 return finish_open_simple(file, error);
66}
67
68static int minix_create(struct user_namespace *mnt_userns, struct inode *dir,
69 struct dentry *dentry, umode_t mode, bool excl)
70{
71 return minix_mknod(mnt_userns, dir, dentry, mode, 0);
72}
73
74static int minix_symlink(struct user_namespace *mnt_userns, struct inode *dir,
75 struct dentry *dentry, const char *symname)
76{
77 int err = -ENAMETOOLONG;
78 int i = strlen(symname)+1;
79 struct inode * inode;
80
81 if (i > dir->i_sb->s_blocksize)
82 goto out;
83
84 inode = minix_new_inode(dir, S_IFLNK | 0777, &err);
85 if (!inode)
86 goto out;
87
88 minix_set_inode(inode, 0);
89 err = page_symlink(inode, symname, i);
90 if (err)
91 goto out_fail;
92
93 err = add_nondir(dentry, inode);
94out:
95 return err;
96
97out_fail:
98 inode_dec_link_count(inode);
99 iput(inode);
100 goto out;
101}
102
103static int minix_link(struct dentry * old_dentry, struct inode * dir,
104 struct dentry *dentry)
105{
106 struct inode *inode = d_inode(old_dentry);
107
108 inode->i_ctime = current_time(inode);
109 inode_inc_link_count(inode);
110 ihold(inode);
111 return add_nondir(dentry, inode);
112}
113
114static int minix_mkdir(struct user_namespace *mnt_userns, struct inode *dir,
115 struct dentry *dentry, umode_t mode)
116{
117 struct inode * inode;
118 int err;
119
120 inode_inc_link_count(dir);
121
122 inode = minix_new_inode(dir, S_IFDIR | mode, &err);
123 if (!inode)
124 goto out_dir;
125
126 minix_set_inode(inode, 0);
127
128 inode_inc_link_count(inode);
129
130 err = minix_make_empty(inode, dir);
131 if (err)
132 goto out_fail;
133
134 err = minix_add_link(dentry, inode);
135 if (err)
136 goto out_fail;
137
138 d_instantiate(dentry, inode);
139out:
140 return err;
141
142out_fail:
143 inode_dec_link_count(inode);
144 inode_dec_link_count(inode);
145 iput(inode);
146out_dir:
147 inode_dec_link_count(dir);
148 goto out;
149}
150
151static int minix_unlink(struct inode * dir, struct dentry *dentry)
152{
153 int err = -ENOENT;
154 struct inode * inode = d_inode(dentry);
155 struct page * page;
156 struct minix_dir_entry * de;
157
158 de = minix_find_entry(dentry, &page);
159 if (!de)
160 goto end_unlink;
161
162 err = minix_delete_entry(de, page);
163 if (err)
164 goto end_unlink;
165
166 inode->i_ctime = dir->i_ctime;
167 inode_dec_link_count(inode);
168end_unlink:
169 return err;
170}
171
172static int minix_rmdir(struct inode * dir, struct dentry *dentry)
173{
174 struct inode * inode = d_inode(dentry);
175 int err = -ENOTEMPTY;
176
177 if (minix_empty_dir(inode)) {
178 err = minix_unlink(dir, dentry);
179 if (!err) {
180 inode_dec_link_count(dir);
181 inode_dec_link_count(inode);
182 }
183 }
184 return err;
185}
186
187static int minix_rename(struct user_namespace *mnt_userns,
188 struct inode *old_dir, struct dentry *old_dentry,
189 struct inode *new_dir, struct dentry *new_dentry,
190 unsigned int flags)
191{
192 struct inode * old_inode = d_inode(old_dentry);
193 struct inode * new_inode = d_inode(new_dentry);
194 struct page * dir_page = NULL;
195 struct minix_dir_entry * dir_de = NULL;
196 struct page * old_page;
197 struct minix_dir_entry * old_de;
198 int err = -ENOENT;
199
200 if (flags & ~RENAME_NOREPLACE)
201 return -EINVAL;
202
203 old_de = minix_find_entry(old_dentry, &old_page);
204 if (!old_de)
205 goto out;
206
207 if (S_ISDIR(old_inode->i_mode)) {
208 err = -EIO;
209 dir_de = minix_dotdot(old_inode, &dir_page);
210 if (!dir_de)
211 goto out_old;
212 }
213
214 if (new_inode) {
215 struct page * new_page;
216 struct minix_dir_entry * new_de;
217
218 err = -ENOTEMPTY;
219 if (dir_de && !minix_empty_dir(new_inode))
220 goto out_dir;
221
222 err = -ENOENT;
223 new_de = minix_find_entry(new_dentry, &new_page);
224 if (!new_de)
225 goto out_dir;
226 minix_set_link(new_de, new_page, old_inode);
227 new_inode->i_ctime = current_time(new_inode);
228 if (dir_de)
229 drop_nlink(new_inode);
230 inode_dec_link_count(new_inode);
231 } else {
232 err = minix_add_link(new_dentry, old_inode);
233 if (err)
234 goto out_dir;
235 if (dir_de)
236 inode_inc_link_count(new_dir);
237 }
238
239 minix_delete_entry(old_de, old_page);
240 mark_inode_dirty(old_inode);
241
242 if (dir_de) {
243 minix_set_link(dir_de, dir_page, new_dir);
244 inode_dec_link_count(old_dir);
245 }
246 return 0;
247
248out_dir:
249 if (dir_de) {
250 kunmap(dir_page);
251 put_page(dir_page);
252 }
253out_old:
254 kunmap(old_page);
255 put_page(old_page);
256out:
257 return err;
258}
259
260/*
261 * directories can handle most operations...
262 */
263const struct inode_operations minix_dir_inode_operations = {
264 .create = minix_create,
265 .lookup = minix_lookup,
266 .link = minix_link,
267 .unlink = minix_unlink,
268 .symlink = minix_symlink,
269 .mkdir = minix_mkdir,
270 .rmdir = minix_rmdir,
271 .mknod = minix_mknod,
272 .rename = minix_rename,
273 .getattr = minix_getattr,
274 .tmpfile = minix_tmpfile,
275};