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/smp_lock.h>
  10 #include <linux/slab.h>
  11 #include "hpfs_fn.h"
  12
  13 static 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
  24 static 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_path.dentry->d_inode;
  30         struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
  31         struct super_block *s = i->i_sb;
  32
  33         lock_kernel();
  34
  35         /*printk("dir lseek\n");*/
  36         if (new_off == 0 || new_off == 1 || new_off == 11 || new_off == 12 || new_off == 13) goto ok;
  37         mutex_lock(&i->i_mutex);
  38         pos = ((loff_t) hpfs_de_as_down_as_possible(s, hpfs_inode->i_dno) << 4) + 1;
  39         while (pos != new_off) {
  40                 if (map_pos_dirent(i, &pos, &qbh)) hpfs_brelse4(&qbh);
  41                 else goto fail;
  42                 if (pos == 12) goto fail;
  43         }
  44         mutex_unlock(&i->i_mutex);
  45 ok:
  46         unlock_kernel();
  47         return filp->f_pos = new_off;
  48 fail:
  49         mutex_unlock(&i->i_mutex);
  50         /*printk("illegal lseek: %016llx\n", new_off);*/
  51         unlock_kernel();
  52         return -ESPIPE;
  53 }
  54
  55 static int hpfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
  56 {
  57         struct inode *inode = filp->f_path.dentry->d_inode;
  58         struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
  59         struct quad_buffer_head qbh;
  60         struct hpfs_dirent *de;
  61         int lc;
  62         long old_pos;
  63         unsigned char *tempname;
  64         int c1, c2 = 0;
  65         int ret = 0;
  66
  67         lock_kernel();
  68
  69         if (hpfs_sb(inode->i_sb)->sb_chk) {
  70                 if (hpfs_chk_sectors(inode->i_sb, inode->i_ino, 1, "dir_fnode")) {
  71                         ret = -EFSERROR;
  72                         goto out;
  73                 }
  74                 if (hpfs_chk_sectors(inode->i_sb, hpfs_inode->i_dno, 4, "dir_dnode")) {
  75                         ret = -EFSERROR;
  76                         goto out;
  77                 }
  78         }
  79         if (hpfs_sb(inode->i_sb)->sb_chk >= 2) {
  80                 struct buffer_head *bh;
  81                 struct fnode *fno;
  82                 int e = 0;
  83                 if (!(fno = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) {
  84                         ret = -EIOERROR;
  85                         goto out;
  86                 }
  87                 if (!fno->dirflag) {
  88                         e = 1;
  89                         hpfs_error(inode->i_sb, "not a directory, fnode %08lx",
  90                                         (unsigned long)inode->i_ino);
  91                 }
  92                 if (hpfs_inode->i_dno != fno->u.external[0].disk_secno) {
  93                         e = 1;
  94                         hpfs_error(inode->i_sb, "corrupted inode: i_dno == %08x, fnode -> dnode == %08x", hpfs_inode->i_dno, fno->u.external[0].disk_secno);
  95                 }
  96                 brelse(bh);
  97                 if (e) {
  98                         ret = -EFSERROR;
  99                         goto out;
 100                 }
 101         }
 102         lc = hpfs_sb(inode->i_sb)->sb_lowercase;
 103         if (filp->f_pos == 12) { /* diff -r requires this (note, that diff -r */
 104                 filp->f_pos = 13; /* also fails on msdos filesystem in 2.0) */
 105                 goto out;
 106         }
 107         if (filp->f_pos == 13) {
 108                 ret = -ENOENT;
 109                 goto out;
 110         }
 111
 112         while (1) {
 113                 again:
 114                 /* This won't work when cycle is longer than number of dirents
 115                    accepted by filldir, but what can I do?
 116                    maybe killall -9 ls helps */
 117                 if (hpfs_sb(inode->i_sb)->sb_chk)
 118                         if (hpfs_stop_cycles(inode->i_sb, filp->f_pos, &c1, &c2, "hpfs_readdir")) {
 119                                 ret = -EFSERROR;
 120                                 goto out;
 121                         }
 122                 if (filp->f_pos == 12)
 123                         goto out;
 124                 if (filp->f_pos == 3 || filp->f_pos == 4 || filp->f_pos == 5) {
 125                         printk("HPFS: warning: pos==%d\n",(int)filp->f_pos);
 126                         goto out;
 127                 }
 128                 if (filp->f_pos == 0) {
 129                         if (filldir(dirent, ".", 1, filp->f_pos, inode->i_ino, DT_DIR) < 0)
 130                                 goto out;
 131                         filp->f_pos = 11;
 132                 }
 133                 if (filp->f_pos == 11) {
 134                         if (filldir(dirent, "..", 2, filp->f_pos, hpfs_inode->i_parent_dir, DT_DIR) < 0)
 135                                 goto out;
 136                         filp->f_pos = 1;
 137                 }
 138                 if (filp->f_pos == 1) {
 139                         filp->f_pos = ((loff_t) hpfs_de_as_down_as_possible(inode->i_sb, hpfs_inode->i_dno) << 4) + 1;
 140                         hpfs_add_pos(inode, &filp->f_pos);
 141                         filp->f_version = inode->i_version;
 142                 }
 143                 old_pos = filp->f_pos;
 144                 if (!(de = map_pos_dirent(inode, &filp->f_pos, &qbh))) {
 145                         ret = -EIOERROR;
 146                         goto out;
 147                 }
 148                 if (de->first || de->last) {
 149                         if (hpfs_sb(inode->i_sb)->sb_chk) {
 150                                 if (de->first && !de->last && (de->namelen != 2
 151                                     || de ->name[0] != 1 || de->name[1] != 1))
 152                                         hpfs_error(inode->i_sb, "hpfs_readdir: bad ^A^A entry; pos = %08lx", old_pos);
 153                                 if (de->last && (de->namelen != 1 || de ->name[0] != 255))
 154                                         hpfs_error(inode->i_sb, "hpfs_readdir: bad \\377 entry; pos = %08lx", old_pos);
 155                         }
 156                         hpfs_brelse4(&qbh);
 157                         goto again;
 158                 }
 159                 tempname = hpfs_translate_name(inode->i_sb, de->name, de->namelen, lc, de->not_8x3);
 160                 if (filldir(dirent, tempname, de->namelen, old_pos, de->fnode, DT_UNKNOWN) < 0) {
 161                         filp->f_pos = old_pos;
 162                         if (tempname != de->name) kfree(tempname);
 163                         hpfs_brelse4(&qbh);
 164                         goto out;
 165                 }
 166                 if (tempname != de->name) kfree(tempname);
 167                 hpfs_brelse4(&qbh);
 168         }
 169 out:
 170         unlock_kernel();
 171         return ret;
 172 }
 173
 174 /*
 175  * lookup.  Search the specified directory for the specified name, set
 176  * *result to the corresponding inode.
 177  *
 178  * lookup uses the inode number to tell read_inode whether it is reading
 179  * the inode of a directory or a file -- file ino's are odd, directory
 180  * ino's are even.  read_inode avoids i/o for file inodes; everything
 181  * needed is up here in the directory.  (And file fnodes are out in
 182  * the boondocks.)
 183  *
 184  *    - M.P.: this is over, sometimes we've got to read file's fnode for eas
 185  *            inode numbers are just fnode sector numbers; iget lock is used
 186  *            to tell read_inode to read fnode or not.
 187  */
 188
 189 struct dentry *hpfs_lookup(struct inode *dir, struct dentry *dentry, struct nameidata *nd)
 190 {
 191         const unsigned char *name = dentry->d_name.name;
 192         unsigned len = dentry->d_name.len;
 193         struct quad_buffer_head qbh;
 194         struct hpfs_dirent *de;
 195         ino_t ino;
 196         int err;
 197         struct inode *result = NULL;
 198         struct hpfs_inode_info *hpfs_result;
 199
 200         lock_kernel();
 201         if ((err = hpfs_chk_name(name, &len))) {
 202                 if (err == -ENAMETOOLONG) {
 203                         unlock_kernel();
 204                         return ERR_PTR(-ENAMETOOLONG);
 205                 }
 206                 goto end_add;
 207         }
 208
 209         /*
 210          * '.' and '..' will never be passed here.
 211          */
 212
 213         de = map_dirent(dir, hpfs_i(dir)->i_dno, name, len, NULL, &qbh);
 214
 215         /*
 216          * This is not really a bailout, just means file not found.
 217          */
 218
 219         if (!de) goto end;
 220
 221         /*
 222          * Get inode number, what we're after.
 223          */
 224
 225         ino = de->fnode;
 226
 227         /*
 228          * Go find or make an inode.
 229          */
 230
 231         result = iget_locked(dir->i_sb, ino);
 232         if (!result) {
 233                 hpfs_error(dir->i_sb, "hpfs_lookup: can't get inode");
 234                 goto bail1;
 235         }
 236         if (result->i_state & I_NEW) {
 237                 hpfs_init_inode(result);
 238                 if (de->directory)
 239                         hpfs_read_inode(result);
 240                 else if (de->ea_size && hpfs_sb(dir->i_sb)->sb_eas)
 241                         hpfs_read_inode(result);
 242                 else {
 243                         result->i_mode |= S_IFREG;
 244                         result->i_mode &= ~0111;
 245                         result->i_op = &hpfs_file_iops;
 246                         result->i_fop = &hpfs_file_ops;
 247                         result->i_nlink = 1;
 248                 }
 249                 unlock_new_inode(result);
 250         }
 251         hpfs_result = hpfs_i(result);
 252         if (!de->directory) hpfs_result->i_parent_dir = dir->i_ino;
 253
 254         hpfs_decide_conv(result, name, len);
 255
 256         if (de->has_acl || de->has_xtd_perm) if (!(dir->i_sb->s_flags & MS_RDONLY)) {
 257                 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");
 258                 goto bail1;
 259         }
 260
 261         /*
 262          * Fill in the info from the directory if this is a newly created
 263          * inode.
 264          */
 265
 266         if (!result->i_ctime.tv_sec) {
 267                 if (!(result->i_ctime.tv_sec = local_to_gmt(dir->i_sb, de->creation_date)))
 268                         result->i_ctime.tv_sec = 1;
 269                 result->i_ctime.tv_nsec = 0;
 270                 result->i_mtime.tv_sec = local_to_gmt(dir->i_sb, de->write_date);
 271                 result->i_mtime.tv_nsec = 0;
 272                 result->i_atime.tv_sec = local_to_gmt(dir->i_sb, de->read_date);
 273                 result->i_atime.tv_nsec = 0;
 274                 hpfs_result->i_ea_size = de->ea_size;
 275                 if (!hpfs_result->i_ea_mode && de->read_only)
 276                         result->i_mode &= ~0222;
 277                 if (!de->directory) {
 278                         if (result->i_size == -1) {
 279                                 result->i_size = de->file_size;
 280                                 result->i_data.a_ops = &hpfs_aops;
 281                                 hpfs_i(result)->mmu_private = result->i_size;
 282                         /*
 283                          * i_blocks should count the fnode and any anodes.
 284                          * We count 1 for the fnode and don't bother about
 285                          * anodes -- the disk heads are on the directory band
 286                          * and we want them to stay there.
 287                          */
 288                                 result->i_blocks = 1 + ((result->i_size + 511) >> 9);
 289                         }
 290                 }
 291         }
 292
 293         hpfs_brelse4(&qbh);
 294
 295         /*
 296          * Made it.
 297          */
 298
 299         end:
 300         end_add:
 301         hpfs_set_dentry_operations(dentry);
 302         unlock_kernel();
 303         d_add(dentry, result);
 304         return NULL;
 305
 306         /*
 307          * Didn't.
 308          */
 309         bail1:
 310
 311         hpfs_brelse4(&qbh);
 312
 313         /*bail:*/
 314
 315         unlock_kernel();
 316         return ERR_PTR(-ENOENT);
 317 }
 318
 319 const struct file_operations hpfs_dir_ops =
 320 {
 321         .llseek         = hpfs_dir_lseek,
 322         .read           = generic_read_dir,
 323         .readdir        = hpfs_readdir,
 324         .release        = hpfs_dir_release,
 325         .fsync          = hpfs_file_fsync,
 326 };