1 // SPDX-License-Identifier: GPL-2.0
2 /*
3 * linux/fs/hpfs/dir.c
4 *
5 * Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
6 *
7 * directory VFS functions
8 */
9
10 #include <linux/slab.h>
11 #include "hpfs_fn.h"
12
13 static int hpfs_dir_release(struct inode *inode, struct file *filp)
14 {
15 hpfs_lock(inode->i_sb);
16 hpfs_del_pos(inode, &filp->f_pos);
17 /*hpfs_write_if_changed(inode);*/
18 hpfs_unlock(inode->i_sb);
19 return 0;
20 }
21
22 /* This is slow, but it's not used often */
23
24 static loff_t hpfs_dir_lseek(struct file *filp, loff_t off, int whence)
25 {
26 loff_t new_off = off + (whence == 1 ? filp->f_pos : 0);
27 loff_t pos;
28 struct quad_buffer_head qbh;
29 struct inode *i = file_inode(filp);
30 struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
31 struct super_block *s = i->i_sb;
32
33 /* Somebody else will have to figure out what to do here */
34 if (whence == SEEK_DATA || whence == SEEK_HOLE)
35 return -EINVAL;
36
37 inode_lock(i);
38 hpfs_lock(s);
39
40 /*pr_info("dir lseek\n");*/
41 if (new_off == 0 || new_off == 1 || new_off == 11 || new_off == 12 || new_off == 13) goto ok;
42 pos = ((loff_t) hpfs_de_as_down_as_possible(s, hpfs_inode->i_dno) << 4) + 1;
43 while (pos != new_off) {
44 if (map_pos_dirent(i, &pos, &qbh)) hpfs_brelse4(&qbh);
45 else goto fail;
46 if (pos == 12) goto fail;
47 }
48 if (unlikely(hpfs_add_pos(i, &filp->f_pos) < 0)) {
49 hpfs_unlock(s);
50 inode_unlock(i);
51 return -ENOMEM;
52 }
53 ok:
54 filp->f_pos = new_off;
55 hpfs_unlock(s);
56 inode_unlock(i);
57 return new_off;
58 fail:
59 /*pr_warn("illegal lseek: %016llx\n", new_off);*/
60 hpfs_unlock(s);
61 inode_unlock(i);
62 return -ESPIPE;
63 }
64
65 static int hpfs_readdir(struct file *file, struct dir_context *ctx)
66 {
67 struct inode *inode = file_inode(file);
68 struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
69 struct quad_buffer_head qbh;
70 struct hpfs_dirent *de;
71 int lc;
72 loff_t next_pos;
73 unsigned char *tempname;
74 int c1, c2 = 0;
75 int ret = 0;
76
77 hpfs_lock(inode->i_sb);
78
79 if (hpfs_sb(inode->i_sb)->sb_chk) {
80 if (hpfs_chk_sectors(inode->i_sb, inode->i_ino, 1, "dir_fnode")) {
81 ret = -EFSERROR;
82 goto out;
83 }
84 if (hpfs_chk_sectors(inode->i_sb, hpfs_inode->i_dno, 4, "dir_dnode")) {
85 ret = -EFSERROR;
86 goto out;
87 }
88 }
89 if (hpfs_sb(inode->i_sb)->sb_chk >= 2) {
90 struct buffer_head *bh;
91 struct fnode *fno;
92 int e = 0;
93 if (!(fno = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) {
94 ret = -EIOERROR;
95 goto out;
96 }
97 if (!fnode_is_dir(fno)) {
98 e = 1;
99 hpfs_error(inode->i_sb, "not a directory, fnode %08lx",
100 (unsigned long)inode->i_ino);
101 }
102 if (hpfs_inode->i_dno != le32_to_cpu(fno->u.external[0].disk_secno)) {
103 e = 1;
104 hpfs_error(inode->i_sb, "corrupted inode: i_dno == %08x, fnode -> dnode == %08x", hpfs_inode->i_dno, le32_to_cpu(fno->u.external[0].disk_secno));
105 }
106 brelse(bh);
107 if (e) {
108 ret = -EFSERROR;
109 goto out;
110 }
111 }
112 lc = hpfs_sb(inode->i_sb)->sb_lowercase;
113 if (ctx->pos == 12) { /* diff -r requires this (note, that diff -r */
114 ctx->pos = 13; /* also fails on msdos filesystem in 2.0) */
115 goto out;
116 }
117 if (ctx->pos == 13) {
118 ret = -ENOENT;
119 goto out;
120 }
121
122 while (1) {
123 again:
124 /* This won't work when cycle is longer than number of dirents
125 accepted by filldir, but what can I do?
126 maybe killall -9 ls helps */
127 if (hpfs_sb(inode->i_sb)->sb_chk)
128 if (hpfs_stop_cycles(inode->i_sb, ctx->pos, &c1, &c2, "hpfs_readdir")) {
129 ret = -EFSERROR;
130 goto out;
131 }
132 if (ctx->pos == 12)
133 goto out;
134 if (ctx->pos == 3 || ctx->pos == 4 || ctx->pos == 5) {
135 pr_err("pos==%d\n", (int)ctx->pos);
136 goto out;
137 }
138 if (ctx->pos == 0) {
139 if (!dir_emit_dot(file, ctx))
140 goto out;
141 ctx->pos = 11;
142 }
143 if (ctx->pos == 11) {
144 if (!dir_emit(ctx, "..", 2, hpfs_inode->i_parent_dir, DT_DIR))
145 goto out;
146 ctx->pos = 1;
147 }
148 if (ctx->pos == 1) {
149 ret = hpfs_add_pos(inode, &file->f_pos);
150 if (unlikely(ret < 0))
151 goto out;
152 ctx->pos = ((loff_t) hpfs_de_as_down_as_possible(inode->i_sb, hpfs_inode->i_dno) << 4) + 1;
153 }
154 next_pos = ctx->pos;
155 if (!(de = map_pos_dirent(inode, &next_pos, &qbh))) {
156 ctx->pos = next_pos;
157 ret = -EIOERROR;
158 goto out;
159 }
160 if (de->first || de->last) {
161 if (hpfs_sb(inode->i_sb)->sb_chk) {
162 if (de->first && !de->last && (de->namelen != 2
163 || de ->name[0] != 1 || de->name[1] != 1))
164 hpfs_error(inode->i_sb, "hpfs_readdir: bad ^A^A entry; pos = %08lx", (unsigned long)ctx->pos);
165 if (de->last && (de->namelen != 1 || de ->name[0] != 255))
166 hpfs_error(inode->i_sb, "hpfs_readdir: bad \\377 entry; pos = %08lx", (unsigned long)ctx->pos);
167 }
168 hpfs_brelse4(&qbh);
169 ctx->pos = next_pos;
170 goto again;
171 }
172 tempname = hpfs_translate_name(inode->i_sb, de->name, de->namelen, lc, de->not_8x3);
173 if (!dir_emit(ctx, tempname, de->namelen, le32_to_cpu(de->fnode), DT_UNKNOWN)) {
174 if (tempname != de->name) kfree(tempname);
175 hpfs_brelse4(&qbh);
176 goto out;
177 }
178 ctx->pos = next_pos;
179 if (tempname != de->name) kfree(tempname);
180 hpfs_brelse4(&qbh);
181 }
182 out:
183 hpfs_unlock(inode->i_sb);
184 return ret;
185 }
186
187 /*
188 * lookup. Search the specified directory for the specified name, set
189 * *result to the corresponding inode.
190 *
191 * lookup uses the inode number to tell read_inode whether it is reading
192 * the inode of a directory or a file -- file ino's are odd, directory
193 * ino's are even. read_inode avoids i/o for file inodes; everything
194 * needed is up here in the directory. (And file fnodes are out in
195 * the boondocks.)
196 *
197 * - M.P.: this is over, sometimes we've got to read file's fnode for eas
198 * inode numbers are just fnode sector numbers; iget lock is used
199 * to tell read_inode to read fnode or not.
200 */
201
202 struct dentry *hpfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
203 {
204 const unsigned char *name = dentry->d_name.name;
205 unsigned len = dentry->d_name.len;
206 struct quad_buffer_head qbh;
207 struct hpfs_dirent *de;
208 ino_t ino;
209 int err;
210 struct inode *result = NULL;
211 struct hpfs_inode_info *hpfs_result;
212
213 hpfs_lock(dir->i_sb);
214 if ((err = hpfs_chk_name(name, &len))) {
215 if (err == -ENAMETOOLONG) {
216 hpfs_unlock(dir->i_sb);
217 return ERR_PTR(-ENAMETOOLONG);
218 }
219 goto end_add;
220 }
221
222 /*
223 * '.' and '..' will never be passed here.
224 */
225
226 de = map_dirent(dir, hpfs_i(dir)->i_dno, name, len, NULL, &qbh);
227
228 /*
229 * This is not really a bailout, just means file not found.
230 */
231
232 if (!de) goto end;
233
234 /*
235 * Get inode number, what we're after.
236 */
237
238 ino = le32_to_cpu(de->fnode);
239
240 /*
241 * Go find or make an inode.
242 */
243
244 result = iget_locked(dir->i_sb, ino);
245 if (!result) {
246 hpfs_error(dir->i_sb, "hpfs_lookup: can't get inode");
247 result = ERR_PTR(-ENOMEM);
248 goto bail1;
249 }
250 if (result->i_state & I_NEW) {
251 hpfs_init_inode(result);
252 if (de->directory)
253 hpfs_read_inode(result);
254 else if (le32_to_cpu(de->ea_size) && hpfs_sb(dir->i_sb)->sb_eas)
255 hpfs_read_inode(result);
256 else {
257 result->i_mode |= S_IFREG;
258 result->i_mode &= ~0111;
259 result->i_op = &hpfs_file_iops;
260 result->i_fop = &hpfs_file_ops;
261 set_nlink(result, 1);
262 }
263 unlock_new_inode(result);
264 }
265 hpfs_result = hpfs_i(result);
266 if (!de->directory) hpfs_result->i_parent_dir = dir->i_ino;
267
268 if (de->has_acl || de->has_xtd_perm) if (!sb_rdonly(dir->i_sb)) {
269 hpfs_error(result->i_sb, "ACLs or XPERM found. This is probably HPFS386. This driver doesn't support it now. Send me some info on these structures");
270 iput(result);
271 result = ERR_PTR(-EINVAL);
272 goto bail1;
273 }
274
275 /*
276 * Fill in the info from the directory if this is a newly created
277 * inode.
278 */
279
280 if (!inode_get_ctime_sec(result)) {
281 time64_t csec = local_to_gmt(dir->i_sb, le32_to_cpu(de->creation_date));
282
283 inode_set_ctime(result, csec ? csec : 1, 0);
284 inode_set_mtime(result,
285 local_to_gmt(dir->i_sb, le32_to_cpu(de->write_date)),
286 0);
287 inode_set_atime(result,
288 local_to_gmt(dir->i_sb, le32_to_cpu(de->read_date)),
289 0);
290 hpfs_result->i_ea_size = le32_to_cpu(de->ea_size);
291 if (!hpfs_result->i_ea_mode && de->read_only)
292 result->i_mode &= ~0222;
293 if (!de->directory) {
294 if (result->i_size == -1) {
295 result->i_size = le32_to_cpu(de->file_size);
296 result->i_data.a_ops = &hpfs_aops;
297 hpfs_i(result)->mmu_private = result->i_size;
298 /*
299 * i_blocks should count the fnode and any anodes.
300 * We count 1 for the fnode and don't bother about
301 * anodes -- the disk heads are on the directory band
302 * and we want them to stay there.
303 */
304 result->i_blocks = 1 + ((result->i_size + 511) >> 9);
305 }
306 }
307 }
308
309 bail1:
310 hpfs_brelse4(&qbh);
311
312 /*
313 * Made it.
314 */
315
316 end:
317 end_add:
318 hpfs_unlock(dir->i_sb);
319 return d_splice_alias(result, dentry);
320 }
321
322 const struct file_operations hpfs_dir_ops =
323 {
324 .llseek = hpfs_dir_lseek,
325 .read = generic_read_dir,
326 .iterate_shared = hpfs_readdir,
327 .release = hpfs_dir_release,
328 .fsync = hpfs_file_fsync,
329 .unlocked_ioctl = hpfs_ioctl,
330 .compat_ioctl = compat_ptr_ioctl,
331 };
332
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