xref: /openbmc/linux/fs/hpfs/dir.c (revision 827634ad)
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 
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 
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 = 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);
48 ok:
49 	filp->f_pos = new_off;
50 	hpfs_unlock(s);
51 	mutex_unlock(&i->i_mutex);
52 	return new_off;
53 fail:
54 	/*pr_warn("illegal lseek: %016llx\n", new_off);*/
55 	hpfs_unlock(s);
56 	mutex_unlock(&i->i_mutex);
57 	return -ESPIPE;
58 }
59 
60 static 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 	}
176 out:
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 
196 struct 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 
323 const 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 };
331