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