fs/hpfs/dir.c

   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
  11 static int hpfs_dir_release(struct inode *inode, struct file *filp)
  12 {
  13         lock_kernel();
  14         hpfs_del_pos(inode, &filp->f_pos);
  15         /*hpfs_write_if_changed(inode);*/
  16         unlock_kernel();
  17         return 0;
  18 }
  19
  20 /* This is slow, but it's not used often */
  21
  22 static loff_t hpfs_dir_lseek(struct file *filp, loff_t off, int whence)
  23 {
  24         loff_t new_off = off + (whence == 1 ? filp->f_pos : 0);
  25         loff_t pos;
  26         struct quad_buffer_head qbh;
  27         struct inode *i = filp->f_path.dentry->d_inode;
  28         struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
  29         struct super_block *s = i->i_sb;
  30
  31         lock_kernel();
  32
  33         /*printk("dir lseek\n");*/
  34         if (new_off == 0 || new_off == 1 || new_off == 11 || new_off == 12 || new_off == 13) goto ok;
  35         mutex_lock(&i->i_mutex);
  36         pos = ((loff_t) hpfs_de_as_down_as_possible(s, hpfs_inode->i_dno) << 4) + 1;
  37         while (pos != new_off) {
  38                 if (map_pos_dirent(i, &pos, &qbh)) hpfs_brelse4(&qbh);
  39                 else goto fail;
  40                 if (pos == 12) goto fail;
  41         }
  42         mutex_unlock(&i->i_mutex);
  43 ok:
  44         unlock_kernel();
  45         return filp->f_pos = new_off;
  46 fail:
  47         mutex_unlock(&i->i_mutex);
  48         /*printk("illegal lseek: %016llx\n", new_off);*/
  49         unlock_kernel();
  50         return -ESPIPE;
  51 }
  52
  53 static int hpfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
  54 {
  55         struct inode *inode = filp->f_path.dentry->d_inode;
  56         struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
  57         struct quad_buffer_head qbh;
  58         struct hpfs_dirent *de;
  59         int lc;
  60         long old_pos;
  61         char *tempname;
  62         int c1, c2 = 0;
  63         int ret = 0;
  64
  65         lock_kernel();
  66
  67         if (hpfs_sb(inode->i_sb)->sb_chk) {
  68                 if (hpfs_chk_sectors(inode->i_sb, inode->i_ino, 1, "dir_fnode")) {
  69                         ret = -EFSERROR;
  70                         goto out;
  71                 }
  72                 if (hpfs_chk_sectors(inode->i_sb, hpfs_inode->i_dno, 4, "dir_dnode")) {
  73                         ret = -EFSERROR;
  74                         goto out;
  75                 }
  76         }
  77         if (hpfs_sb(inode->i_sb)->sb_chk >= 2) {
  78                 struct buffer_head *bh;
  79                 struct fnode *fno;
  80                 int e = 0;
  81                 if (!(fno = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) {
  82                         ret = -EIOERROR;
  83                         goto out;
  84                 }
  85                 if (!fno->dirflag) {
  86                         e = 1;
  87                         hpfs_error(inode->i_sb, "not a directory, fnode %08lx",
  88                                         (unsigned long)inode->i_ino);
  89                 }
  90                 if (hpfs_inode->i_dno != fno->u.external[0].disk_secno) {
  91                         e = 1;
  92                         hpfs_error(inode->i_sb, "corrupted inode: i_dno == %08x, fnode -> dnode == %08x", hpfs_inode->i_dno, fno->u.external[0].disk_secno);
  93                 }
  94                 brelse(bh);
  95                 if (e) {
  96                         ret = -EFSERROR;
  97                         goto out;
  98                 }
  99         }
 100         lc = hpfs_sb(inode->i_sb)->sb_lowercase;
 101         if (filp->f_pos == 12) { /* diff -r requires this (note, that diff -r */
 102                 filp->f_pos = 13; /* also fails on msdos filesystem in 2.0) */
 103                 goto out;
 104         }
 105         if (filp->f_pos == 13) {
 106                 ret = -ENOENT;
 107                 goto out;
 108         }
 109
 110         while (1) {
 111                 again:
 112                 /* This won't work when cycle is longer than number of dirents
 113                    accepted by filldir, but what can I do?
 114                    maybe killall -9 ls helps */
 115                 if (hpfs_sb(inode->i_sb)->sb_chk)
 116                         if (hpfs_stop_cycles(inode->i_sb, filp->f_pos, &c1, &c2, "hpfs_readdir")) {
 117                                 ret = -EFSERROR;
 118                                 goto out;
 119                         }
 120                 if (filp->f_pos == 12)
 121                         goto out;
 122                 if (filp->f_pos == 3 || filp->f_pos == 4 || filp->f_pos == 5) {
 123                         printk("HPFS: warning: pos==%d\n",(int)filp->f_pos);
 124                         goto out;
 125                 }
 126                 if (filp->f_pos == 0) {
 127                         if (filldir(dirent, ".", 1, filp->f_pos, inode->i_ino, DT_DIR) < 0)
 128                                 goto out;
 129                         filp->f_pos = 11;
 130                 }
 131                 if (filp->f_pos == 11) {
 132                         if (filldir(dirent, "..", 2, filp->f_pos, hpfs_inode->i_parent_dir, DT_DIR) < 0)
 133                                 goto out;
 134                         filp->f_pos = 1;
 135                 }
 136                 if (filp->f_pos == 1) {
 137                         filp->f_pos = ((loff_t) hpfs_de_as_down_as_possible(inode->i_sb, hpfs_inode->i_dno) << 4) + 1;
 138                         hpfs_add_pos(inode, &filp->f_pos);
 139                         filp->f_version = inode->i_version;
 140                 }
 141                 old_pos = filp->f_pos;
 142                 if (!(de = map_pos_dirent(inode, &filp->f_pos, &qbh))) {
 143                         ret = -EIOERROR;
 144                         goto out;
 145                 }
 146                 if (de->first || de->last) {
 147                         if (hpfs_sb(inode->i_sb)->sb_chk) {
 148                                 if (de->first && !de->last && (de->namelen != 2
 149                                     || de ->name[0] != 1 || de->name[1] != 1))
 150                                         hpfs_error(inode->i_sb, "hpfs_readdir: bad ^A^A entry; pos = %08lx", old_pos);
 151                                 if (de->last && (de->namelen != 1 || de ->name[0] != 255))
 152                                         hpfs_error(inode->i_sb, "hpfs_readdir: bad \\377 entry; pos = %08lx", old_pos);
 153                         }
 154                         hpfs_brelse4(&qbh);
 155                         goto again;
 156                 }
 157                 tempname = hpfs_translate_name(inode->i_sb, de->name, de->namelen, lc, de->not_8x3);
 158                 if (filldir(dirent, tempname, de->namelen, old_pos, de->fnode, DT_UNKNOWN) < 0) {
 159                         filp->f_pos = old_pos;
 160                         if (tempname != (char *)de->name) kfree(tempname);
 161                         hpfs_brelse4(&qbh);
 162                         goto out;
 163                 }
 164                 if (tempname != (char *)de->name) kfree(tempname);
 165                 hpfs_brelse4(&qbh);
 166         }
 167 out:
 168         unlock_kernel();
 169         return ret;
 170 }
 171
 172 /*
 173  * lookup.  Search the specified directory for the specified name, set
 174  * *result to the corresponding inode.
 175  *
 176  * lookup uses the inode number to tell read_inode whether it is reading
 177  * the inode of a directory or a file -- file ino's are odd, directory
 178  * ino's are even.  read_inode avoids i/o for file inodes; everything
 179  * needed is up here in the directory.  (And file fnodes are out in
 180  * the boondocks.)
 181  *
 182  *    - M.P.: this is over, sometimes we've got to read file's fnode for eas
 183  *            inode numbers are just fnode sector numbers; iget lock is used
 184  *            to tell read_inode to read fnode or not.
 185  */
 186
 187 struct dentry *hpfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
 188 {
 189         const char *name = dentry->d_name.name;
 190         unsigned len = dentry->d_name.len;
 191         struct quad_buffer_head qbh;
 192         struct hpfs_dirent *de;
 193         ino_t ino;
 194         int err;
 195         struct inode *result = NULL;
 196         struct hpfs_inode_info *hpfs_result;
 197
 198         lock_kernel();
 199         if ((err = hpfs_chk_name((char *)name, &len))) {
 200                 if (err == -ENAMETOOLONG) {
 201                         unlock_kernel();
 202                         return ERR_PTR(-ENAMETOOLONG);
 203                 }
 204                 goto end_add;
 205         }
 206
 207         /*
 208          * '.' and '..' will never be passed here.
 209          */
 210
 211         de = map_dirent(dir, hpfs_i(dir)->i_dno, (char *) name, len, NULL, &qbh);
 212
 213         /*
 214          * This is not really a bailout, just means file not found.
 215          */
 216
 217         if (!de) goto end;
 218
 219         /*
 220          * Get inode number, what we're after.
 221          */
 222
 223         ino = de->fnode;
 224
 225         /*
 226          * Go find or make an inode.
 227          */
 228
 229         result = iget_locked(dir->i_sb, ino);
 230         if (!result) {
 231                 hpfs_error(dir->i_sb, "hpfs_lookup: can't get inode");
 232                 goto bail1;
 233         }
 234         if (result->i_state & I_NEW) {
 235                 hpfs_init_inode(result);
 236                 if (de->directory)
 237                         hpfs_read_inode(result);
 238                 else if (de->ea_size && hpfs_sb(dir->i_sb)->sb_eas)
 239                         hpfs_read_inode(result);
 240                 else {
 241                         result->i_mode |= S_IFREG;
 242                         result->i_mode &= ~0111;
 243                         result->i_op = &hpfs_file_iops;
 244                         result->i_fop = &hpfs_file_ops;
 245                         result->i_nlink = 1;
 246                 }
 247                 unlock_new_inode(result);
 248         }
 249         hpfs_result = hpfs_i(result);
 250         if (!de->directory) hpfs_result->i_parent_dir = dir->i_ino;
 251
 252         hpfs_decide_conv(result, (char *)name, len);
 253
 254         if (de->has_acl || de->has_xtd_perm) if (!(dir->i_sb->s_flags & MS_RDONLY)) {
 255                 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");
 256                 goto bail1;
 257         }
 258
 259         /*
 260          * Fill in the info from the directory if this is a newly created
 261          * inode.
 262          */
 263
 264         if (!result->i_ctime.tv_sec) {
 265                 if (!(result->i_ctime.tv_sec = local_to_gmt(dir->i_sb, de->creation_date)))
 266                         result->i_ctime.tv_sec = 1;
 267                 result->i_ctime.tv_nsec = 0;
 268                 result->i_mtime.tv_sec = local_to_gmt(dir->i_sb, de->write_date);
 269                 result->i_mtime.tv_nsec = 0;
 270                 result->i_atime.tv_sec = local_to_gmt(dir->i_sb, de->read_date);
 271                 result->i_atime.tv_nsec = 0;
 272                 hpfs_result->i_ea_size = de->ea_size;
 273                 if (!hpfs_result->i_ea_mode && de->read_only)
 274                         result->i_mode &= ~0222;
 275                 if (!de->directory) {
 276                         if (result->i_size == -1) {
 277                                 result->i_size = de->file_size;
 278                                 result->i_data.a_ops = &hpfs_aops;
 279                                 hpfs_i(result)->mmu_private = result->i_size;
 280                         /*
 281                          * i_blocks should count the fnode and any anodes.
 282                          * We count 1 for the fnode and don't bother about
 283                          * anodes -- the disk heads are on the directory band
 284                          * and we want them to stay there.
 285                          */
 286                                 result->i_blocks = 1 + ((result->i_size + 511) >> 9);
 287                         }
 288                 }
 289         }
 290
 291         hpfs_brelse4(&qbh);
 292
 293         /*
 294          * Made it.
 295          */
 296
 297         end:
 298         end_add:
 299         hpfs_set_dentry_operations(dentry);
 300         unlock_kernel();
 301         d_add(dentry, result);
 302         return NULL;
 303
 304         /*
 305          * Didn't.
 306          */
 307         bail1:
 308
 309         hpfs_brelse4(&qbh);
 310
 311         /*bail:*/
 312
 313         unlock_kernel();
 314         return ERR_PTR(-ENOENT);
 315 }
 316
 317 const struct file_operations hpfs_dir_ops =
 318 {
 319         .llseek         = hpfs_dir_lseek,
 320         .read           = generic_read_dir,
 321         .readdir        = hpfs_readdir,
 322         .release        = hpfs_dir_release,
 323         .fsync          = hpfs_file_fsync,
 324 };