[PATCH] BLOCK: Move the ReiserFS device ioctl compat stuff to the ReiserFS driver...
[linux-2.6.git] / fs / reiserfs / dir.c
1 /*
2  * Copyright 2000 by Hans Reiser, licensing governed by reiserfs/README
3  */
4
5 #include <linux/string.h>
6 #include <linux/errno.h>
7 #include <linux/fs.h>
8 #include <linux/reiserfs_fs.h>
9 #include <linux/stat.h>
10 #include <linux/smp_lock.h>
11 #include <linux/buffer_head.h>
12 #include <asm/uaccess.h>
13
14 extern struct reiserfs_key MIN_KEY;
15
16 static int reiserfs_readdir(struct file *, void *, filldir_t);
17 static int reiserfs_dir_fsync(struct file *filp, struct dentry *dentry,
18                               int datasync);
19
20 const struct file_operations reiserfs_dir_operations = {
21         .read = generic_read_dir,
22         .readdir = reiserfs_readdir,
23         .fsync = reiserfs_dir_fsync,
24         .ioctl = reiserfs_ioctl,
25 #ifdef CONFIG_COMPAT
26         .compat_ioctl = reiserfs_compat_ioctl,
27 #endif
28 };
29
30 static int reiserfs_dir_fsync(struct file *filp, struct dentry *dentry,
31                               int datasync)
32 {
33         struct inode *inode = dentry->d_inode;
34         int err;
35         reiserfs_write_lock(inode->i_sb);
36         err = reiserfs_commit_for_inode(inode);
37         reiserfs_write_unlock(inode->i_sb);
38         if (err < 0)
39                 return err;
40         return 0;
41 }
42
43 #define store_ih(where,what) copy_item_head (where, what)
44
45 //
46 static int reiserfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
47 {
48         struct inode *inode = filp->f_dentry->d_inode;
49         struct cpu_key pos_key; /* key of current position in the directory (key of directory entry) */
50         INITIALIZE_PATH(path_to_entry);
51         struct buffer_head *bh;
52         int item_num, entry_num;
53         const struct reiserfs_key *rkey;
54         struct item_head *ih, tmp_ih;
55         int search_res;
56         char *local_buf;
57         loff_t next_pos;
58         char small_buf[32];     /* avoid kmalloc if we can */
59         struct reiserfs_dir_entry de;
60         int ret = 0;
61
62         reiserfs_write_lock(inode->i_sb);
63
64         reiserfs_check_lock_depth(inode->i_sb, "readdir");
65
66         /* form key for search the next directory entry using f_pos field of
67            file structure */
68         make_cpu_key(&pos_key, inode,
69                      (filp->f_pos) ? (filp->f_pos) : DOT_OFFSET, TYPE_DIRENTRY,
70                      3);
71         next_pos = cpu_key_k_offset(&pos_key);
72
73         /*  reiserfs_warning (inode->i_sb, "reiserfs_readdir 1: f_pos = %Ld", filp->f_pos); */
74
75         path_to_entry.reada = PATH_READA;
76         while (1) {
77               research:
78                 /* search the directory item, containing entry with specified key */
79                 search_res =
80                     search_by_entry_key(inode->i_sb, &pos_key, &path_to_entry,
81                                         &de);
82                 if (search_res == IO_ERROR) {
83                         // FIXME: we could just skip part of directory which could
84                         // not be read
85                         ret = -EIO;
86                         goto out;
87                 }
88                 entry_num = de.de_entry_num;
89                 bh = de.de_bh;
90                 item_num = de.de_item_num;
91                 ih = de.de_ih;
92                 store_ih(&tmp_ih, ih);
93
94                 /* we must have found item, that is item of this directory, */
95                 RFALSE(COMP_SHORT_KEYS(&(ih->ih_key), &pos_key),
96                        "vs-9000: found item %h does not match to dir we readdir %K",
97                        ih, &pos_key);
98                 RFALSE(item_num > B_NR_ITEMS(bh) - 1,
99                        "vs-9005 item_num == %d, item amount == %d",
100                        item_num, B_NR_ITEMS(bh));
101
102                 /* and entry must be not more than number of entries in the item */
103                 RFALSE(I_ENTRY_COUNT(ih) < entry_num,
104                        "vs-9010: entry number is too big %d (%d)",
105                        entry_num, I_ENTRY_COUNT(ih));
106
107                 if (search_res == POSITION_FOUND
108                     || entry_num < I_ENTRY_COUNT(ih)) {
109                         /* go through all entries in the directory item beginning from the entry, that has been found */
110                         struct reiserfs_de_head *deh =
111                             B_I_DEH(bh, ih) + entry_num;
112
113                         for (; entry_num < I_ENTRY_COUNT(ih);
114                              entry_num++, deh++) {
115                                 int d_reclen;
116                                 char *d_name;
117                                 off_t d_off;
118                                 ino_t d_ino;
119
120                                 if (!de_visible(deh))
121                                         /* it is hidden entry */
122                                         continue;
123                                 d_reclen = entry_length(bh, ih, entry_num);
124                                 d_name = B_I_DEH_ENTRY_FILE_NAME(bh, ih, deh);
125                                 if (!d_name[d_reclen - 1])
126                                         d_reclen = strlen(d_name);
127
128                                 if (d_reclen >
129                                     REISERFS_MAX_NAME(inode->i_sb->
130                                                       s_blocksize)) {
131                                         /* too big to send back to VFS */
132                                         continue;
133                                 }
134
135                                 /* Ignore the .reiserfs_priv entry */
136                                 if (reiserfs_xattrs(inode->i_sb) &&
137                                     !old_format_only(inode->i_sb) &&
138                                     filp->f_dentry == inode->i_sb->s_root &&
139                                     REISERFS_SB(inode->i_sb)->priv_root &&
140                                     REISERFS_SB(inode->i_sb)->priv_root->d_inode
141                                     && deh_objectid(deh) ==
142                                     le32_to_cpu(INODE_PKEY
143                                                 (REISERFS_SB(inode->i_sb)->
144                                                  priv_root->d_inode)->
145                                                 k_objectid)) {
146                                         continue;
147                                 }
148
149                                 d_off = deh_offset(deh);
150                                 filp->f_pos = d_off;
151                                 d_ino = deh_objectid(deh);
152                                 if (d_reclen <= 32) {
153                                         local_buf = small_buf;
154                                 } else {
155                                         local_buf = kmalloc(d_reclen,
156                                                             GFP_NOFS);
157                                         if (!local_buf) {
158                                                 pathrelse(&path_to_entry);
159                                                 ret = -ENOMEM;
160                                                 goto out;
161                                         }
162                                         if (item_moved(&tmp_ih, &path_to_entry)) {
163                                                 kfree(local_buf);
164                                                 goto research;
165                                         }
166                                 }
167                                 // Note, that we copy name to user space via temporary
168                                 // buffer (local_buf) because filldir will block if
169                                 // user space buffer is swapped out. At that time
170                                 // entry can move to somewhere else
171                                 memcpy(local_buf, d_name, d_reclen);
172                                 if (filldir
173                                     (dirent, local_buf, d_reclen, d_off, d_ino,
174                                      DT_UNKNOWN) < 0) {
175                                         if (local_buf != small_buf) {
176                                                 kfree(local_buf);
177                                         }
178                                         goto end;
179                                 }
180                                 if (local_buf != small_buf) {
181                                         kfree(local_buf);
182                                 }
183                                 // next entry should be looked for with such offset
184                                 next_pos = deh_offset(deh) + 1;
185
186                                 if (item_moved(&tmp_ih, &path_to_entry)) {
187                                         goto research;
188                                 }
189                         }       /* for */
190                 }
191
192                 if (item_num != B_NR_ITEMS(bh) - 1)
193                         // end of directory has been reached
194                         goto end;
195
196                 /* item we went through is last item of node. Using right
197                    delimiting key check is it directory end */
198                 rkey = get_rkey(&path_to_entry, inode->i_sb);
199                 if (!comp_le_keys(rkey, &MIN_KEY)) {
200                         /* set pos_key to key, that is the smallest and greater
201                            that key of the last entry in the item */
202                         set_cpu_key_k_offset(&pos_key, next_pos);
203                         continue;
204                 }
205
206                 if (COMP_SHORT_KEYS(rkey, &pos_key)) {
207                         // end of directory has been reached
208                         goto end;
209                 }
210
211                 /* directory continues in the right neighboring block */
212                 set_cpu_key_k_offset(&pos_key,
213                                      le_key_k_offset(KEY_FORMAT_3_5, rkey));
214
215         }                       /* while */
216
217       end:
218         filp->f_pos = next_pos;
219         pathrelse(&path_to_entry);
220         reiserfs_check_path(&path_to_entry);
221       out:
222         reiserfs_write_unlock(inode->i_sb);
223         return ret;
224 }
225
226 /* compose directory item containing "." and ".." entries (entries are
227    not aligned to 4 byte boundary) */
228 /* the last four params are LE */
229 void make_empty_dir_item_v1(char *body, __le32 dirid, __le32 objid,
230                             __le32 par_dirid, __le32 par_objid)
231 {
232         struct reiserfs_de_head *deh;
233
234         memset(body, 0, EMPTY_DIR_SIZE_V1);
235         deh = (struct reiserfs_de_head *)body;
236
237         /* direntry header of "." */
238         put_deh_offset(&(deh[0]), DOT_OFFSET);
239         /* these two are from make_le_item_head, and are are LE */
240         deh[0].deh_dir_id = dirid;
241         deh[0].deh_objectid = objid;
242         deh[0].deh_state = 0;   /* Endian safe if 0 */
243         put_deh_location(&(deh[0]), EMPTY_DIR_SIZE_V1 - strlen("."));
244         mark_de_visible(&(deh[0]));
245
246         /* direntry header of ".." */
247         put_deh_offset(&(deh[1]), DOT_DOT_OFFSET);
248         /* key of ".." for the root directory */
249         /* these two are from the inode, and are are LE */
250         deh[1].deh_dir_id = par_dirid;
251         deh[1].deh_objectid = par_objid;
252         deh[1].deh_state = 0;   /* Endian safe if 0 */
253         put_deh_location(&(deh[1]), deh_location(&(deh[0])) - strlen(".."));
254         mark_de_visible(&(deh[1]));
255
256         /* copy ".." and "." */
257         memcpy(body + deh_location(&(deh[0])), ".", 1);
258         memcpy(body + deh_location(&(deh[1])), "..", 2);
259 }
260
261 /* compose directory item containing "." and ".." entries */
262 void make_empty_dir_item(char *body, __le32 dirid, __le32 objid,
263                          __le32 par_dirid, __le32 par_objid)
264 {
265         struct reiserfs_de_head *deh;
266
267         memset(body, 0, EMPTY_DIR_SIZE);
268         deh = (struct reiserfs_de_head *)body;
269
270         /* direntry header of "." */
271         put_deh_offset(&(deh[0]), DOT_OFFSET);
272         /* these two are from make_le_item_head, and are are LE */
273         deh[0].deh_dir_id = dirid;
274         deh[0].deh_objectid = objid;
275         deh[0].deh_state = 0;   /* Endian safe if 0 */
276         put_deh_location(&(deh[0]), EMPTY_DIR_SIZE - ROUND_UP(strlen(".")));
277         mark_de_visible(&(deh[0]));
278
279         /* direntry header of ".." */
280         put_deh_offset(&(deh[1]), DOT_DOT_OFFSET);
281         /* key of ".." for the root directory */
282         /* these two are from the inode, and are are LE */
283         deh[1].deh_dir_id = par_dirid;
284         deh[1].deh_objectid = par_objid;
285         deh[1].deh_state = 0;   /* Endian safe if 0 */
286         put_deh_location(&(deh[1]),
287                          deh_location(&(deh[0])) - ROUND_UP(strlen("..")));
288         mark_de_visible(&(deh[1]));
289
290         /* copy ".." and "." */
291         memcpy(body + deh_location(&(deh[0])), ".", 1);
292         memcpy(body + deh_location(&(deh[1])), "..", 2);
293 }