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