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1/*
2 * linux/fs/sysv/namei.c
3 *
4 * minix/namei.c
5 * Copyright (C) 1991, 1992 Linus Torvalds
6 *
7 * coh/namei.c
8 * Copyright (C) 1993 Pascal Haible, Bruno Haible
9 *
10 * sysv/namei.c
11 * Copyright (C) 1993 Bruno Haible
12 * Copyright (C) 1997, 1998 Krzysztof G. Baranowski
13 */
14
15#include <linux/pagemap.h>
16#include "sysv.h"
17
18static int add_nondir(struct dentry *dentry, struct inode *inode)
19{
20 int err = sysv_add_link(dentry, inode);
21 if (!err) {
22 d_instantiate(dentry, inode);
23 return 0;
24 }
25 inode_dec_link_count(inode);
26 iput(inode);
27 return err;
28}
29
30static int sysv_hash(const struct dentry *dentry, struct qstr *qstr)
31{
32 /* Truncate the name in place, avoids having to define a compare
33 function. */
34 if (qstr->len > SYSV_NAMELEN) {
35 qstr->len = SYSV_NAMELEN;
36 qstr->hash = full_name_hash(qstr->name, qstr->len);
37 }
38 return 0;
39}
40
41const struct dentry_operations sysv_dentry_operations = {
42 .d_hash = sysv_hash,
43};
44
45static struct dentry *sysv_lookup(struct inode * dir, struct dentry * dentry, unsigned int flags)
46{
47 struct inode * inode = NULL;
48 ino_t ino;
49
50 if (dentry->d_name.len > SYSV_NAMELEN)
51 return ERR_PTR(-ENAMETOOLONG);
52 ino = sysv_inode_by_name(dentry);
53
54 if (ino) {
55 inode = sysv_iget(dir->i_sb, ino);
56 if (IS_ERR(inode))
57 return ERR_CAST(inode);
58 }
59 d_add(dentry, inode);
60 return NULL;
61}
62
63static int sysv_mknod(struct inode * dir, struct dentry * dentry, umode_t mode, dev_t rdev)
64{
65 struct inode * inode;
66 int err;
67
68 if (!old_valid_dev(rdev))
69 return -EINVAL;
70
71 inode = sysv_new_inode(dir, mode);
72 err = PTR_ERR(inode);
73
74 if (!IS_ERR(inode)) {
75 sysv_set_inode(inode, rdev);
76 mark_inode_dirty(inode);
77 err = add_nondir(dentry, inode);
78 }
79 return err;
80}
81
82static int sysv_create(struct inode * dir, struct dentry * dentry, umode_t mode, bool excl)
83{
84 return sysv_mknod(dir, dentry, mode, 0);
85}
86
87static int sysv_symlink(struct inode * dir, struct dentry * dentry,
88 const char * symname)
89{
90 int err = -ENAMETOOLONG;
91 int l = strlen(symname)+1;
92 struct inode * inode;
93
94 if (l > dir->i_sb->s_blocksize)
95 goto out;
96
97 inode = sysv_new_inode(dir, S_IFLNK|0777);
98 err = PTR_ERR(inode);
99 if (IS_ERR(inode))
100 goto out;
101
102 sysv_set_inode(inode, 0);
103 err = page_symlink(inode, symname, l);
104 if (err)
105 goto out_fail;
106
107 mark_inode_dirty(inode);
108 err = add_nondir(dentry, inode);
109out:
110 return err;
111
112out_fail:
113 inode_dec_link_count(inode);
114 iput(inode);
115 goto out;
116}
117
118static int sysv_link(struct dentry * old_dentry, struct inode * dir,
119 struct dentry * dentry)
120{
121 struct inode *inode = d_inode(old_dentry);
122
123 inode->i_ctime = CURRENT_TIME_SEC;
124 inode_inc_link_count(inode);
125 ihold(inode);
126
127 return add_nondir(dentry, inode);
128}
129
130static int sysv_mkdir(struct inode * dir, struct dentry *dentry, umode_t mode)
131{
132 struct inode * inode;
133 int err;
134
135 inode_inc_link_count(dir);
136
137 inode = sysv_new_inode(dir, S_IFDIR|mode);
138 err = PTR_ERR(inode);
139 if (IS_ERR(inode))
140 goto out_dir;
141
142 sysv_set_inode(inode, 0);
143
144 inode_inc_link_count(inode);
145
146 err = sysv_make_empty(inode, dir);
147 if (err)
148 goto out_fail;
149
150 err = sysv_add_link(dentry, inode);
151 if (err)
152 goto out_fail;
153
154 d_instantiate(dentry, inode);
155out:
156 return err;
157
158out_fail:
159 inode_dec_link_count(inode);
160 inode_dec_link_count(inode);
161 iput(inode);
162out_dir:
163 inode_dec_link_count(dir);
164 goto out;
165}
166
167static int sysv_unlink(struct inode * dir, struct dentry * dentry)
168{
169 struct inode * inode = d_inode(dentry);
170 struct page * page;
171 struct sysv_dir_entry * de;
172 int err = -ENOENT;
173
174 de = sysv_find_entry(dentry, &page);
175 if (!de)
176 goto out;
177
178 err = sysv_delete_entry (de, page);
179 if (err)
180 goto out;
181
182 inode->i_ctime = dir->i_ctime;
183 inode_dec_link_count(inode);
184out:
185 return err;
186}
187
188static int sysv_rmdir(struct inode * dir, struct dentry * dentry)
189{
190 struct inode *inode = d_inode(dentry);
191 int err = -ENOTEMPTY;
192
193 if (sysv_empty_dir(inode)) {
194 err = sysv_unlink(dir, dentry);
195 if (!err) {
196 inode->i_size = 0;
197 inode_dec_link_count(inode);
198 inode_dec_link_count(dir);
199 }
200 }
201 return err;
202}
203
204/*
205 * Anybody can rename anything with this: the permission checks are left to the
206 * higher-level routines.
207 */
208static int sysv_rename(struct inode * old_dir, struct dentry * old_dentry,
209 struct inode * new_dir, struct dentry * new_dentry)
210{
211 struct inode * old_inode = d_inode(old_dentry);
212 struct inode * new_inode = d_inode(new_dentry);
213 struct page * dir_page = NULL;
214 struct sysv_dir_entry * dir_de = NULL;
215 struct page * old_page;
216 struct sysv_dir_entry * old_de;
217 int err = -ENOENT;
218
219 old_de = sysv_find_entry(old_dentry, &old_page);
220 if (!old_de)
221 goto out;
222
223 if (S_ISDIR(old_inode->i_mode)) {
224 err = -EIO;
225 dir_de = sysv_dotdot(old_inode, &dir_page);
226 if (!dir_de)
227 goto out_old;
228 }
229
230 if (new_inode) {
231 struct page * new_page;
232 struct sysv_dir_entry * new_de;
233
234 err = -ENOTEMPTY;
235 if (dir_de && !sysv_empty_dir(new_inode))
236 goto out_dir;
237
238 err = -ENOENT;
239 new_de = sysv_find_entry(new_dentry, &new_page);
240 if (!new_de)
241 goto out_dir;
242 sysv_set_link(new_de, new_page, old_inode);
243 new_inode->i_ctime = CURRENT_TIME_SEC;
244 if (dir_de)
245 drop_nlink(new_inode);
246 inode_dec_link_count(new_inode);
247 } else {
248 err = sysv_add_link(new_dentry, old_inode);
249 if (err)
250 goto out_dir;
251 if (dir_de)
252 inode_inc_link_count(new_dir);
253 }
254
255 sysv_delete_entry(old_de, old_page);
256 mark_inode_dirty(old_inode);
257
258 if (dir_de) {
259 sysv_set_link(dir_de, dir_page, new_dir);
260 inode_dec_link_count(old_dir);
261 }
262 return 0;
263
264out_dir:
265 if (dir_de) {
266 kunmap(dir_page);
267 put_page(dir_page);
268 }
269out_old:
270 kunmap(old_page);
271 put_page(old_page);
272out:
273 return err;
274}
275
276/*
277 * directories can handle most operations...
278 */
279const struct inode_operations sysv_dir_inode_operations = {
280 .create = sysv_create,
281 .lookup = sysv_lookup,
282 .link = sysv_link,
283 .unlink = sysv_unlink,
284 .symlink = sysv_symlink,
285 .mkdir = sysv_mkdir,
286 .rmdir = sysv_rmdir,
287 .mknod = sysv_mknod,
288 .rename = sysv_rename,
289 .getattr = sysv_getattr,
290};
1// SPDX-License-Identifier: GPL-2.0
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>
17#include "sysv.h"
18
19static 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 }
26 inode_dec_link_count(inode);
27 iput(inode);
28 return err;
29}
30
31static int sysv_hash(const struct dentry *dentry, struct qstr *qstr)
32{
33 /* Truncate the name in place, avoids having to define a compare
34 function. */
35 if (qstr->len > SYSV_NAMELEN) {
36 qstr->len = SYSV_NAMELEN;
37 qstr->hash = full_name_hash(dentry, qstr->name, qstr->len);
38 }
39 return 0;
40}
41
42const struct dentry_operations sysv_dentry_operations = {
43 .d_hash = sysv_hash,
44};
45
46static struct dentry *sysv_lookup(struct inode * dir, struct dentry * dentry, unsigned int flags)
47{
48 struct inode * inode = NULL;
49 ino_t ino;
50
51 if (dentry->d_name.len > SYSV_NAMELEN)
52 return ERR_PTR(-ENAMETOOLONG);
53 ino = sysv_inode_by_name(dentry);
54
55 if (ino) {
56 inode = sysv_iget(dir->i_sb, ino);
57 if (IS_ERR(inode))
58 return ERR_CAST(inode);
59 }
60 d_add(dentry, inode);
61 return NULL;
62}
63
64static int sysv_mknod(struct inode * dir, struct dentry * dentry, umode_t mode, dev_t rdev)
65{
66 struct inode * inode;
67 int err;
68
69 if (!old_valid_dev(rdev))
70 return -EINVAL;
71
72 inode = sysv_new_inode(dir, mode);
73 err = PTR_ERR(inode);
74
75 if (!IS_ERR(inode)) {
76 sysv_set_inode(inode, rdev);
77 mark_inode_dirty(inode);
78 err = add_nondir(dentry, inode);
79 }
80 return err;
81}
82
83static int sysv_create(struct inode * dir, struct dentry * dentry, umode_t mode, bool excl)
84{
85 return sysv_mknod(dir, dentry, mode, 0);
86}
87
88static int sysv_symlink(struct inode * dir, struct dentry * dentry,
89 const char * symname)
90{
91 int err = -ENAMETOOLONG;
92 int l = strlen(symname)+1;
93 struct inode * inode;
94
95 if (l > dir->i_sb->s_blocksize)
96 goto out;
97
98 inode = sysv_new_inode(dir, S_IFLNK|0777);
99 err = PTR_ERR(inode);
100 if (IS_ERR(inode))
101 goto out;
102
103 sysv_set_inode(inode, 0);
104 err = page_symlink(inode, symname, l);
105 if (err)
106 goto out_fail;
107
108 mark_inode_dirty(inode);
109 err = add_nondir(dentry, inode);
110out:
111 return err;
112
113out_fail:
114 inode_dec_link_count(inode);
115 iput(inode);
116 goto out;
117}
118
119static int sysv_link(struct dentry * old_dentry, struct inode * dir,
120 struct dentry * dentry)
121{
122 struct inode *inode = d_inode(old_dentry);
123
124 inode->i_ctime = current_time(inode);
125 inode_inc_link_count(inode);
126 ihold(inode);
127
128 return add_nondir(dentry, inode);
129}
130
131static int sysv_mkdir(struct inode * dir, struct dentry *dentry, umode_t mode)
132{
133 struct inode * inode;
134 int err;
135
136 inode_inc_link_count(dir);
137
138 inode = sysv_new_inode(dir, S_IFDIR|mode);
139 err = PTR_ERR(inode);
140 if (IS_ERR(inode))
141 goto out_dir;
142
143 sysv_set_inode(inode, 0);
144
145 inode_inc_link_count(inode);
146
147 err = sysv_make_empty(inode, dir);
148 if (err)
149 goto out_fail;
150
151 err = sysv_add_link(dentry, inode);
152 if (err)
153 goto out_fail;
154
155 d_instantiate(dentry, inode);
156out:
157 return err;
158
159out_fail:
160 inode_dec_link_count(inode);
161 inode_dec_link_count(inode);
162 iput(inode);
163out_dir:
164 inode_dec_link_count(dir);
165 goto out;
166}
167
168static int sysv_unlink(struct inode * dir, struct dentry * dentry)
169{
170 struct inode * inode = d_inode(dentry);
171 struct page * page;
172 struct sysv_dir_entry * de;
173 int err = -ENOENT;
174
175 de = sysv_find_entry(dentry, &page);
176 if (!de)
177 goto out;
178
179 err = sysv_delete_entry (de, page);
180 if (err)
181 goto out;
182
183 inode->i_ctime = dir->i_ctime;
184 inode_dec_link_count(inode);
185out:
186 return err;
187}
188
189static int sysv_rmdir(struct inode * dir, struct dentry * dentry)
190{
191 struct inode *inode = d_inode(dentry);
192 int err = -ENOTEMPTY;
193
194 if (sysv_empty_dir(inode)) {
195 err = sysv_unlink(dir, dentry);
196 if (!err) {
197 inode->i_size = 0;
198 inode_dec_link_count(inode);
199 inode_dec_link_count(dir);
200 }
201 }
202 return err;
203}
204
205/*
206 * Anybody can rename anything with this: the permission checks are left to the
207 * higher-level routines.
208 */
209static int sysv_rename(struct inode * old_dir, struct dentry * old_dentry,
210 struct inode * new_dir, struct dentry * new_dentry,
211 unsigned int flags)
212{
213 struct inode * old_inode = d_inode(old_dentry);
214 struct inode * new_inode = d_inode(new_dentry);
215 struct page * dir_page = NULL;
216 struct sysv_dir_entry * dir_de = NULL;
217 struct page * old_page;
218 struct sysv_dir_entry * old_de;
219 int err = -ENOENT;
220
221 if (flags & ~RENAME_NOREPLACE)
222 return -EINVAL;
223
224 old_de = sysv_find_entry(old_dentry, &old_page);
225 if (!old_de)
226 goto out;
227
228 if (S_ISDIR(old_inode->i_mode)) {
229 err = -EIO;
230 dir_de = sysv_dotdot(old_inode, &dir_page);
231 if (!dir_de)
232 goto out_old;
233 }
234
235 if (new_inode) {
236 struct page * new_page;
237 struct sysv_dir_entry * new_de;
238
239 err = -ENOTEMPTY;
240 if (dir_de && !sysv_empty_dir(new_inode))
241 goto out_dir;
242
243 err = -ENOENT;
244 new_de = sysv_find_entry(new_dentry, &new_page);
245 if (!new_de)
246 goto out_dir;
247 sysv_set_link(new_de, new_page, old_inode);
248 new_inode->i_ctime = current_time(new_inode);
249 if (dir_de)
250 drop_nlink(new_inode);
251 inode_dec_link_count(new_inode);
252 } else {
253 err = sysv_add_link(new_dentry, old_inode);
254 if (err)
255 goto out_dir;
256 if (dir_de)
257 inode_inc_link_count(new_dir);
258 }
259
260 sysv_delete_entry(old_de, old_page);
261 mark_inode_dirty(old_inode);
262
263 if (dir_de) {
264 sysv_set_link(dir_de, dir_page, new_dir);
265 inode_dec_link_count(old_dir);
266 }
267 return 0;
268
269out_dir:
270 if (dir_de) {
271 kunmap(dir_page);
272 put_page(dir_page);
273 }
274out_old:
275 kunmap(old_page);
276 put_page(old_page);
277out:
278 return err;
279}
280
281/*
282 * directories can handle most operations...
283 */
284const struct inode_operations sysv_dir_inode_operations = {
285 .create = sysv_create,
286 .lookup = sysv_lookup,
287 .link = sysv_link,
288 .unlink = sysv_unlink,
289 .symlink = sysv_symlink,
290 .mkdir = sysv_mkdir,
291 .rmdir = sysv_rmdir,
292 .mknod = sysv_mknod,
293 .rename = sysv_rename,
294 .getattr = sysv_getattr,
295};