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