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 = file_inode(filp);
  29         struct hpfs_inode_info *hpfs_inode = hpfs_i(i);
  30         struct super_block *s = i->i_sb;
  31
  32         /* Somebody else will have to figure out what to do here */
  33         if (whence == SEEK_DATA || whence == SEEK_HOLE)
  34                 return -EINVAL;
  35
  36         hpfs_lock(s);
  37
  38         /*printk("dir lseek\n");*/
  39         if (new_off == 0 || new_off == 1 || new_off == 11 || new_off == 12 || new_off == 13) goto ok;
  40         mutex_lock(&i->i_mutex);
  41         pos = ((loff_t) hpfs_de_as_down_as_possible(s, hpfs_inode->i_dno) << 4) + 1;
  42         while (pos != new_off) {
  43                 if (map_pos_dirent(i, &pos, &qbh)) hpfs_brelse4(&qbh);
  44                 else goto fail;
  45                 if (pos == 12) goto fail;
  46         }
  47         mutex_unlock(&i->i_mutex);
  48 ok:
  49         hpfs_unlock(s);
  50         return filp->f_pos = new_off;
  51 fail:
  52         mutex_unlock(&i->i_mutex);
  53         /*printk("illegal lseek: %016llx\n", new_off);*/
  54         hpfs_unlock(s);
  55         return -ESPIPE;
  56 }
  57
  58 static int hpfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
  59 {
  60         struct inode *inode = file_inode(filp);
  61         struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
  62         struct quad_buffer_head qbh;
  63         struct hpfs_dirent *de;
  64         int lc;
  65         long old_pos;
  66         unsigned char *tempname;
  67         int c1, c2 = 0;
  68         int ret = 0;
  69
  70         hpfs_lock(inode->i_sb);
  71
  72         if (hpfs_sb(inode->i_sb)->sb_chk) {
  73                 if (hpfs_chk_sectors(inode->i_sb, inode->i_ino, 1, "dir_fnode")) {
  74                         ret = -EFSERROR;
  75                         goto out;
  76                 }
  77                 if (hpfs_chk_sectors(inode->i_sb, hpfs_inode->i_dno, 4, "dir_dnode")) {
  78                         ret = -EFSERROR;
  79                         goto out;
  80                 }
  81         }
  82         if (hpfs_sb(inode->i_sb)->sb_chk >= 2) {
  83                 struct buffer_head *bh;
  84                 struct fnode *fno;
  85                 int e = 0;
  86                 if (!(fno = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) {
  87                         ret = -EIOERROR;
  88                         goto out;
  89                 }
  90                 if (!fnode_is_dir(fno)) {
  91                         e = 1;
  92                         hpfs_error(inode->i_sb, "not a directory, fnode %08lx",
  93                                         (unsigned long)inode->i_ino);
  94                 }
  95                 if (hpfs_inode->i_dno != le32_to_cpu(fno->u.external[0].disk_secno)) {
  96                         e = 1;
  97                         hpfs_error(inode->i_sb, "corrupted inode: i_dno == %08x, fnode -> dnode == %08x", hpfs_inode->i_dno, le32_to_cpu(fno->u.external[0].disk_secno));
  98                 }
  99                 brelse(bh);
 100                 if (e) {
 101                         ret = -EFSERROR;
 102                         goto out;
 103                 }
 104         }
 105         lc = hpfs_sb(inode->i_sb)->sb_lowercase;
 106         if (filp->f_pos == 12) { /* diff -r requires this (note, that diff -r */
 107                 filp->f_pos = 13; /* also fails on msdos filesystem in 2.0) */
 108                 goto out;
 109         }
 110         if (filp->f_pos == 13) {
 111                 ret = -ENOENT;
 112                 goto out;
 113         }
 114
 115         while (1) {
 116                 again:
 117                 /* This won't work when cycle is longer than number of dirents
 118                    accepted by filldir, but what can I do?
 119                    maybe killall -9 ls helps */
 120                 if (hpfs_sb(inode->i_sb)->sb_chk)
 121                         if (hpfs_stop_cycles(inode->i_sb, filp->f_pos, &c1, &c2, "hpfs_readdir")) {
 122                                 ret = -EFSERROR;
 123                                 goto out;
 124                         }
 125                 if (filp->f_pos == 12)
 126                         goto out;
 127                 if (filp->f_pos == 3 || filp->f_pos == 4 || filp->f_pos == 5) {
 128                         printk("HPFS: warning: pos==%d\n",(int)filp->f_pos);
 129                         goto out;
 130                 }
 131                 if (filp->f_pos == 0) {
 132                         if (filldir(dirent, ".", 1, filp->f_pos, inode->i_ino, DT_DIR) < 0)
 133                                 goto out;
 134                         filp->f_pos = 11;
 135                 }
 136                 if (filp->f_pos == 11) {
 137                         if (filldir(dirent, "..", 2, filp->f_pos, hpfs_inode->i_parent_dir, DT_DIR) < 0)
 138                                 goto out;
 139                         filp->f_pos = 1;
 140                 }
 141                 if (filp->f_pos == 1) {
 142                         filp->f_pos = ((loff_t) hpfs_de_as_down_as_possible(inode->i_sb, hpfs_inode->i_dno) << 4) + 1;
 143                         hpfs_add_pos(inode, &filp->f_pos);
 144                         filp->f_version = inode->i_version;
 145                 }
 146                 old_pos = filp->f_pos;
 147                 if (!(de = map_pos_dirent(inode, &filp->f_pos, &qbh))) {
 148                         ret = -EIOERROR;
 149                         goto out;
 150                 }
 151                 if (de->first || de->last) {
 152                         if (hpfs_sb(inode->i_sb)->sb_chk) {
 153                                 if (de->first && !de->last && (de->namelen != 2
 154                                     || de ->name[0] != 1 || de->name[1] != 1))
 155                                         hpfs_error(inode->i_sb, "hpfs_readdir: bad ^A^A entry; pos = %08lx", old_pos);
 156                                 if (de->last && (de->namelen != 1 || de ->name[0] != 255))
 157                                         hpfs_error(inode->i_sb, "hpfs_readdir: bad \\377 entry; pos = %08lx", old_pos);
 158                         }
 159                         hpfs_brelse4(&qbh);
 160                         goto again;
 161                 }
 162                 tempname = hpfs_translate_name(inode->i_sb, de->name, de->namelen, lc, de->not_8x3);
 163                 if (filldir(dirent, tempname, de->namelen, old_pos, le32_to_cpu(de->fnode), DT_UNKNOWN) < 0) {
 164                         filp->f_pos = old_pos;
 165                         if (tempname != de->name) kfree(tempname);
 166                         hpfs_brelse4(&qbh);
 167                         goto out;
 168                 }
 169                 if (tempname != de->name) kfree(tempname);
 170                 hpfs_brelse4(&qbh);
 171         }
 172 out:
 173         hpfs_unlock(inode->i_sb);
 174         return ret;
 175 }
 176
 177 /*
 178  * lookup.  Search the specified directory for the specified name, set
 179  * *result to the corresponding inode.
 180  *
 181  * lookup uses the inode number to tell read_inode whether it is reading
 182  * the inode of a directory or a file -- file ino's are odd, directory
 183  * ino's are even.  read_inode avoids i/o for file inodes; everything
 184  * needed is up here in the directory.  (And file fnodes are out in
 185  * the boondocks.)
 186  *
 187  *    - M.P.: this is over, sometimes we've got to read file's fnode for eas
 188  *            inode numbers are just fnode sector numbers; iget lock is used
 189  *            to tell read_inode to read fnode or not.
 190  */
 191
 192 struct dentry *hpfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
 193 {
 194         const unsigned char *name = dentry->d_name.name;
 195         unsigned len = dentry->d_name.len;
 196         struct quad_buffer_head qbh;
 197         struct hpfs_dirent *de;
 198         ino_t ino;
 199         int err;
 200         struct inode *result = NULL;
 201         struct hpfs_inode_info *hpfs_result;
 202
 203         hpfs_lock(dir->i_sb);
 204         if ((err = hpfs_chk_name(name, &len))) {
 205                 if (err == -ENAMETOOLONG) {
 206                         hpfs_unlock(dir->i_sb);
 207                         return ERR_PTR(-ENAMETOOLONG);
 208                 }
 209                 goto end_add;
 210         }
 211
 212         /*
 213          * '.' and '..' will never be passed here.
 214          */
 215
 216         de = map_dirent(dir, hpfs_i(dir)->i_dno, name, len, NULL, &qbh);
 217
 218         /*
 219          * This is not really a bailout, just means file not found.
 220          */
 221
 222         if (!de) goto end;
 223
 224         /*
 225          * Get inode number, what we're after.
 226          */
 227
 228         ino = le32_to_cpu(de->fnode);
 229
 230         /*
 231          * Go find or make an inode.
 232          */
 233
 234         result = iget_locked(dir->i_sb, ino);
 235         if (!result) {
 236                 hpfs_error(dir->i_sb, "hpfs_lookup: can't get inode");
 237                 goto bail1;
 238         }
 239         if (result->i_state & I_NEW) {
 240                 hpfs_init_inode(result);
 241                 if (de->directory)
 242                         hpfs_read_inode(result);
 243                 else if (le32_to_cpu(de->ea_size) && hpfs_sb(dir->i_sb)->sb_eas)
 244                         hpfs_read_inode(result);
 245                 else {
 246                         result->i_mode |= S_IFREG;
 247                         result->i_mode &= ~0111;
 248                         result->i_op = &hpfs_file_iops;
 249                         result->i_fop = &hpfs_file_ops;
 250                         set_nlink(result, 1);
 251                 }
 252                 unlock_new_inode(result);
 253         }
 254         hpfs_result = hpfs_i(result);
 255         if (!de->directory) hpfs_result->i_parent_dir = dir->i_ino;
 256
 257         if (de->has_acl || de->has_xtd_perm) if (!(dir->i_sb->s_flags & MS_RDONLY)) {
 258                 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");
 259                 goto bail1;
 260         }
 261
 262         /*
 263          * Fill in the info from the directory if this is a newly created
 264          * inode.
 265          */
 266
 267         if (!result->i_ctime.tv_sec) {
 268                 if (!(result->i_ctime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(de->creation_date))))
 269                         result->i_ctime.tv_sec = 1;
 270                 result->i_ctime.tv_nsec = 0;
 271                 result->i_mtime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(de->write_date));
 272                 result->i_mtime.tv_nsec = 0;
 273                 result->i_atime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(de->read_date));
 274                 result->i_atime.tv_nsec = 0;
 275                 hpfs_result->i_ea_size = le32_to_cpu(de->ea_size);
 276                 if (!hpfs_result->i_ea_mode && de->read_only)
 277                         result->i_mode &= ~0222;
 278                 if (!de->directory) {
 279                         if (result->i_size == -1) {
 280                                 result->i_size = le32_to_cpu(de->file_size);
 281                                 result->i_data.a_ops = &hpfs_aops;
 282                                 hpfs_i(result)->mmu_private = result->i_size;
 283                         /*
 284                          * i_blocks should count the fnode and any anodes.
 285                          * We count 1 for the fnode and don't bother about
 286                          * anodes -- the disk heads are on the directory band
 287                          * and we want them to stay there.
 288                          */
 289                                 result->i_blocks = 1 + ((result->i_size + 511) >> 9);
 290                         }
 291                 }
 292         }
 293
 294         hpfs_brelse4(&qbh);
 295
 296         /*
 297          * Made it.
 298          */
 299
 300         end:
 301         end_add:
 302         hpfs_unlock(dir->i_sb);
 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         hpfs_unlock(dir->i_sb);
 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 };