xref: /linux/fs/hpfs/dir.c (revision d524dac9279b6a41ffdf7ff7958c577f2e387db6)
1 /*
2  *  linux/fs/hpfs/dir.c
3  *
4  *  Mikulas Patocka (mikulas@artax.karlin.mff.cuni.cz), 1998-1999
5  *
6  *  directory VFS functions
7  */
8 
9 #include <linux/smp_lock.h>
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 	lock_kernel();
16 	hpfs_del_pos(inode, &filp->f_pos);
17 	/*hpfs_write_if_changed(inode);*/
18 	unlock_kernel();
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 = filp->f_path.dentry->d_inode;
30 	struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
31 	struct super_block *s = i->i_sb;
32 
33 	lock_kernel();
34 
35 	/*printk("dir lseek\n");*/
36 	if (new_off == 0 || new_off == 1 || new_off == 11 || new_off == 12 || new_off == 13) goto ok;
37 	mutex_lock(&i->i_mutex);
38 	pos = ((loff_t) hpfs_de_as_down_as_possible(s, hpfs_inode->i_dno) << 4) + 1;
39 	while (pos != new_off) {
40 		if (map_pos_dirent(i, &pos, &qbh)) hpfs_brelse4(&qbh);
41 		else goto fail;
42 		if (pos == 12) goto fail;
43 	}
44 	mutex_unlock(&i->i_mutex);
45 ok:
46 	unlock_kernel();
47 	return filp->f_pos = new_off;
48 fail:
49 	mutex_unlock(&i->i_mutex);
50 	/*printk("illegal lseek: %016llx\n", new_off);*/
51 	unlock_kernel();
52 	return -ESPIPE;
53 }
54 
55 static int hpfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
56 {
57 	struct inode *inode = filp->f_path.dentry->d_inode;
58 	struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
59 	struct quad_buffer_head qbh;
60 	struct hpfs_dirent *de;
61 	int lc;
62 	long old_pos;
63 	unsigned char *tempname;
64 	int c1, c2 = 0;
65 	int ret = 0;
66 
67 	lock_kernel();
68 
69 	if (hpfs_sb(inode->i_sb)->sb_chk) {
70 		if (hpfs_chk_sectors(inode->i_sb, inode->i_ino, 1, "dir_fnode")) {
71 			ret = -EFSERROR;
72 			goto out;
73 		}
74 		if (hpfs_chk_sectors(inode->i_sb, hpfs_inode->i_dno, 4, "dir_dnode")) {
75 			ret = -EFSERROR;
76 			goto out;
77 		}
78 	}
79 	if (hpfs_sb(inode->i_sb)->sb_chk >= 2) {
80 		struct buffer_head *bh;
81 		struct fnode *fno;
82 		int e = 0;
83 		if (!(fno = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) {
84 			ret = -EIOERROR;
85 			goto out;
86 		}
87 		if (!fno->dirflag) {
88 			e = 1;
89 			hpfs_error(inode->i_sb, "not a directory, fnode %08lx",
90 					(unsigned long)inode->i_ino);
91 		}
92 		if (hpfs_inode->i_dno != fno->u.external[0].disk_secno) {
93 			e = 1;
94 			hpfs_error(inode->i_sb, "corrupted inode: i_dno == %08x, fnode -> dnode == %08x", hpfs_inode->i_dno, fno->u.external[0].disk_secno);
95 		}
96 		brelse(bh);
97 		if (e) {
98 			ret = -EFSERROR;
99 			goto out;
100 		}
101 	}
102 	lc = hpfs_sb(inode->i_sb)->sb_lowercase;
103 	if (filp->f_pos == 12) { /* diff -r requires this (note, that diff -r */
104 		filp->f_pos = 13; /* also fails on msdos filesystem in 2.0) */
105 		goto out;
106 	}
107 	if (filp->f_pos == 13) {
108 		ret = -ENOENT;
109 		goto out;
110 	}
111 
112 	while (1) {
113 		again:
114 		/* This won't work when cycle is longer than number of dirents
115 		   accepted by filldir, but what can I do?
116 		   maybe killall -9 ls helps */
117 		if (hpfs_sb(inode->i_sb)->sb_chk)
118 			if (hpfs_stop_cycles(inode->i_sb, filp->f_pos, &c1, &c2, "hpfs_readdir")) {
119 				ret = -EFSERROR;
120 				goto out;
121 			}
122 		if (filp->f_pos == 12)
123 			goto out;
124 		if (filp->f_pos == 3 || filp->f_pos == 4 || filp->f_pos == 5) {
125 			printk("HPFS: warning: pos==%d\n",(int)filp->f_pos);
126 			goto out;
127 		}
128 		if (filp->f_pos == 0) {
129 			if (filldir(dirent, ".", 1, filp->f_pos, inode->i_ino, DT_DIR) < 0)
130 				goto out;
131 			filp->f_pos = 11;
132 		}
133 		if (filp->f_pos == 11) {
134 			if (filldir(dirent, "..", 2, filp->f_pos, hpfs_inode->i_parent_dir, DT_DIR) < 0)
135 				goto out;
136 			filp->f_pos = 1;
137 		}
138 		if (filp->f_pos == 1) {
139 			filp->f_pos = ((loff_t) hpfs_de_as_down_as_possible(inode->i_sb, hpfs_inode->i_dno) << 4) + 1;
140 			hpfs_add_pos(inode, &filp->f_pos);
141 			filp->f_version = inode->i_version;
142 		}
143 		old_pos = filp->f_pos;
144 		if (!(de = map_pos_dirent(inode, &filp->f_pos, &qbh))) {
145 			ret = -EIOERROR;
146 			goto out;
147 		}
148 		if (de->first || de->last) {
149 			if (hpfs_sb(inode->i_sb)->sb_chk) {
150 				if (de->first && !de->last && (de->namelen != 2
151 				    || de ->name[0] != 1 || de->name[1] != 1))
152 					hpfs_error(inode->i_sb, "hpfs_readdir: bad ^A^A entry; pos = %08lx", old_pos);
153 				if (de->last && (de->namelen != 1 || de ->name[0] != 255))
154 					hpfs_error(inode->i_sb, "hpfs_readdir: bad \\377 entry; pos = %08lx", old_pos);
155 			}
156 			hpfs_brelse4(&qbh);
157 			goto again;
158 		}
159 		tempname = hpfs_translate_name(inode->i_sb, de->name, de->namelen, lc, de->not_8x3);
160 		if (filldir(dirent, tempname, de->namelen, old_pos, de->fnode, DT_UNKNOWN) < 0) {
161 			filp->f_pos = old_pos;
162 			if (tempname != de->name) kfree(tempname);
163 			hpfs_brelse4(&qbh);
164 			goto out;
165 		}
166 		if (tempname != de->name) kfree(tempname);
167 		hpfs_brelse4(&qbh);
168 	}
169 out:
170 	unlock_kernel();
171 	return ret;
172 }
173 
174 /*
175  * lookup.  Search the specified directory for the specified name, set
176  * *result to the corresponding inode.
177  *
178  * lookup uses the inode number to tell read_inode whether it is reading
179  * the inode of a directory or a file -- file ino's are odd, directory
180  * ino's are even.  read_inode avoids i/o for file inodes; everything
181  * needed is up here in the directory.  (And file fnodes are out in
182  * the boondocks.)
183  *
184  *    - M.P.: this is over, sometimes we've got to read file's fnode for eas
185  *	      inode numbers are just fnode sector numbers; iget lock is used
186  *	      to tell read_inode to read fnode or not.
187  */
188 
189 struct dentry *hpfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
190 {
191 	const unsigned char *name = dentry->d_name.name;
192 	unsigned len = dentry->d_name.len;
193 	struct quad_buffer_head qbh;
194 	struct hpfs_dirent *de;
195 	ino_t ino;
196 	int err;
197 	struct inode *result = NULL;
198 	struct hpfs_inode_info *hpfs_result;
199 
200 	lock_kernel();
201 	if ((err = hpfs_chk_name(name, &len))) {
202 		if (err == -ENAMETOOLONG) {
203 			unlock_kernel();
204 			return ERR_PTR(-ENAMETOOLONG);
205 		}
206 		goto end_add;
207 	}
208 
209 	/*
210 	 * '.' and '..' will never be passed here.
211 	 */
212 
213 	de = map_dirent(dir, hpfs_i(dir)->i_dno, name, len, NULL, &qbh);
214 
215 	/*
216 	 * This is not really a bailout, just means file not found.
217 	 */
218 
219 	if (!de) goto end;
220 
221 	/*
222 	 * Get inode number, what we're after.
223 	 */
224 
225 	ino = de->fnode;
226 
227 	/*
228 	 * Go find or make an inode.
229 	 */
230 
231 	result = iget_locked(dir->i_sb, ino);
232 	if (!result) {
233 		hpfs_error(dir->i_sb, "hpfs_lookup: can't get inode");
234 		goto bail1;
235 	}
236 	if (result->i_state & I_NEW) {
237 		hpfs_init_inode(result);
238 		if (de->directory)
239 			hpfs_read_inode(result);
240 		else if (de->ea_size && hpfs_sb(dir->i_sb)->sb_eas)
241 			hpfs_read_inode(result);
242 		else {
243 			result->i_mode |= S_IFREG;
244 			result->i_mode &= ~0111;
245 			result->i_op = &hpfs_file_iops;
246 			result->i_fop = &hpfs_file_ops;
247 			result->i_nlink = 1;
248 		}
249 		unlock_new_inode(result);
250 	}
251 	hpfs_result = hpfs_i(result);
252 	if (!de->directory) hpfs_result->i_parent_dir = dir->i_ino;
253 
254 	hpfs_decide_conv(result, name, len);
255 
256 	if (de->has_acl || de->has_xtd_perm) if (!(dir->i_sb->s_flags & MS_RDONLY)) {
257 		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");
258 		goto bail1;
259 	}
260 
261 	/*
262 	 * Fill in the info from the directory if this is a newly created
263 	 * inode.
264 	 */
265 
266 	if (!result->i_ctime.tv_sec) {
267 		if (!(result->i_ctime.tv_sec = local_to_gmt(dir->i_sb, de->creation_date)))
268 			result->i_ctime.tv_sec = 1;
269 		result->i_ctime.tv_nsec = 0;
270 		result->i_mtime.tv_sec = local_to_gmt(dir->i_sb, de->write_date);
271 		result->i_mtime.tv_nsec = 0;
272 		result->i_atime.tv_sec = local_to_gmt(dir->i_sb, de->read_date);
273 		result->i_atime.tv_nsec = 0;
274 		hpfs_result->i_ea_size = de->ea_size;
275 		if (!hpfs_result->i_ea_mode && de->read_only)
276 			result->i_mode &= ~0222;
277 		if (!de->directory) {
278 			if (result->i_size == -1) {
279 				result->i_size = de->file_size;
280 				result->i_data.a_ops = &hpfs_aops;
281 				hpfs_i(result)->mmu_private = result->i_size;
282 			/*
283 			 * i_blocks should count the fnode and any anodes.
284 			 * We count 1 for the fnode and don't bother about
285 			 * anodes -- the disk heads are on the directory band
286 			 * and we want them to stay there.
287 			 */
288 				result->i_blocks = 1 + ((result->i_size + 511) >> 9);
289 			}
290 		}
291 	}
292 
293 	hpfs_brelse4(&qbh);
294 
295 	/*
296 	 * Made it.
297 	 */
298 
299 	end:
300 	end_add:
301 	unlock_kernel();
302 	d_add(dentry, result);
303 	return NULL;
304 
305 	/*
306 	 * Didn't.
307 	 */
308 	bail1:
309 
310 	hpfs_brelse4(&qbh);
311 
312 	/*bail:*/
313 
314 	unlock_kernel();
315 	return ERR_PTR(-ENOENT);
316 }
317 
318 const struct file_operations hpfs_dir_ops =
319 {
320 	.llseek		= hpfs_dir_lseek,
321 	.read		= generic_read_dir,
322 	.readdir	= hpfs_readdir,
323 	.release	= hpfs_dir_release,
324 	.fsync		= hpfs_file_fsync,
325 };
326