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