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         mutex_lock(&i->i_mutex);
  37         hpfs_lock(s);
  38
  39         /*printk("dir lseek\n");*/
  40         if (new_off == 0 || new_off == 1 || new_off == 11 || new_off == 12 || new_off == 13) goto ok;
  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         hpfs_add_pos(i, &filp->f_pos);
  48 ok:
  49         filp->f_pos = new_off;
  50         hpfs_unlock(s);
  51         mutex_unlock(&i->i_mutex);
  52         return new_off;
  53 fail:
  54         /*printk("illegal lseek: %016llx\n", new_off);*/
  55         hpfs_unlock(s);
  56         mutex_unlock(&i->i_mutex);
  57         return -ESPIPE;
  58 }
  59
  60 static int hpfs_readdir(struct file *file, struct dir_context *ctx)
  61 {
  62         struct inode *inode = file_inode(file);
  63         struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
  64         struct quad_buffer_head qbh;
  65         struct hpfs_dirent *de;
  66         int lc;
  67         loff_t next_pos;
  68         unsigned char *tempname;
  69         int c1, c2 = 0;
  70         int ret = 0;
  71
  72         hpfs_lock(inode->i_sb);
  73
  74         if (hpfs_sb(inode->i_sb)->sb_chk) {
  75                 if (hpfs_chk_sectors(inode->i_sb, inode->i_ino, 1, "dir_fnode")) {
  76                         ret = -EFSERROR;
  77                         goto out;
  78                 }
  79                 if (hpfs_chk_sectors(inode->i_sb, hpfs_inode->i_dno, 4, "dir_dnode")) {
  80                         ret = -EFSERROR;
  81                         goto out;
  82                 }
  83         }
  84         if (hpfs_sb(inode->i_sb)->sb_chk >= 2) {
  85                 struct buffer_head *bh;
  86                 struct fnode *fno;
  87                 int e = 0;
  88                 if (!(fno = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) {
  89                         ret = -EIOERROR;
  90                         goto out;
  91                 }
  92                 if (!fnode_is_dir(fno)) {
  93                         e = 1;
  94                         hpfs_error(inode->i_sb, "not a directory, fnode %08lx",
  95                                         (unsigned long)inode->i_ino);
  96                 }
  97                 if (hpfs_inode->i_dno != le32_to_cpu(fno->u.external[0].disk_secno)) {
  98                         e = 1;
  99                         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));
 100                 }
 101                 brelse(bh);
 102                 if (e) {
 103                         ret = -EFSERROR;
 104                         goto out;
 105                 }
 106         }
 107         lc = hpfs_sb(inode->i_sb)->sb_lowercase;
 108         if (ctx->pos == 12) { /* diff -r requires this (note, that diff -r */
 109                 ctx->pos = 13; /* also fails on msdos filesystem in 2.0) */
 110                 goto out;
 111         }
 112         if (ctx->pos == 13) {
 113                 ret = -ENOENT;
 114                 goto out;
 115         }
 116
 117         while (1) {
 118                 again:
 119                 /* This won't work when cycle is longer than number of dirents
 120                    accepted by filldir, but what can I do?
 121                    maybe killall -9 ls helps */
 122                 if (hpfs_sb(inode->i_sb)->sb_chk)
 123                         if (hpfs_stop_cycles(inode->i_sb, ctx->pos, &c1, &c2, "hpfs_readdir")) {
 124                                 ret = -EFSERROR;
 125                                 goto out;
 126                         }
 127                 if (ctx->pos == 12)
 128                         goto out;
 129                 if (ctx->pos == 3 || ctx->pos == 4 || ctx->pos == 5) {
 130                         printk("HPFS: warning: pos==%d\n",(int)ctx->pos);
 131                         goto out;
 132                 }
 133                 if (ctx->pos == 0) {
 134                         if (!dir_emit_dot(file, ctx))
 135                                 goto out;
 136                         ctx->pos = 11;
 137                 }
 138                 if (ctx->pos == 11) {
 139                         if (!dir_emit(ctx, "..", 2, hpfs_inode->i_parent_dir, DT_DIR))
 140                                 goto out;
 141                         ctx->pos = 1;
 142                 }
 143                 if (ctx->pos == 1) {
 144                         ctx->pos = ((loff_t) hpfs_de_as_down_as_possible(inode->i_sb, hpfs_inode->i_dno) << 4) + 1;
 145                         hpfs_add_pos(inode, &file->f_pos);
 146                         file->f_version = inode->i_version;
 147                 }
 148                 next_pos = ctx->pos;
 149                 if (!(de = map_pos_dirent(inode, &next_pos, &qbh))) {
 150                         ctx->pos = next_pos;
 151                         ret = -EIOERROR;
 152                         goto out;
 153                 }
 154                 if (de->first || de->last) {
 155                         if (hpfs_sb(inode->i_sb)->sb_chk) {
 156                                 if (de->first && !de->last && (de->namelen != 2
 157                                     || de ->name[0] != 1 || de->name[1] != 1))
 158                                         hpfs_error(inode->i_sb, "hpfs_readdir: bad ^A^A entry; pos = %08lx", (unsigned long)ctx->pos);
 159                                 if (de->last && (de->namelen != 1 || de ->name[0] != 255))
 160                                         hpfs_error(inode->i_sb, "hpfs_readdir: bad \\377 entry; pos = %08lx", (unsigned long)ctx->pos);
 161                         }
 162                         hpfs_brelse4(&qbh);
 163                         ctx->pos = next_pos;
 164                         goto again;
 165                 }
 166                 tempname = hpfs_translate_name(inode->i_sb, de->name, de->namelen, lc, de->not_8x3);
 167                 if (!dir_emit(ctx, tempname, de->namelen, le32_to_cpu(de->fnode), DT_UNKNOWN)) {
 168                         if (tempname != de->name) kfree(tempname);
 169                         hpfs_brelse4(&qbh);
 170                         goto out;
 171                 }
 172                 ctx->pos = next_pos;
 173                 if (tempname != de->name) kfree(tempname);
 174                 hpfs_brelse4(&qbh);
 175         }
 176 out:
 177         hpfs_unlock(inode->i_sb);
 178         return ret;
 179 }
 180
 181 /*
 182  * lookup.  Search the specified directory for the specified name, set
 183  * *result to the corresponding inode.
 184  *
 185  * lookup uses the inode number to tell read_inode whether it is reading
 186  * the inode of a directory or a file -- file ino's are odd, directory
 187  * ino's are even.  read_inode avoids i/o for file inodes; everything
 188  * needed is up here in the directory.  (And file fnodes are out in
 189  * the boondocks.)
 190  *
 191  *    - M.P.: this is over, sometimes we've got to read file's fnode for eas
 192  *            inode numbers are just fnode sector numbers; iget lock is used
 193  *            to tell read_inode to read fnode or not.
 194  */
 195
 196 struct dentry *hpfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
 197 {
 198         const unsigned char *name = dentry->d_name.name;
 199         unsigned len = dentry->d_name.len;
 200         struct quad_buffer_head qbh;
 201         struct hpfs_dirent *de;
 202         ino_t ino;
 203         int err;
 204         struct inode *result = NULL;
 205         struct hpfs_inode_info *hpfs_result;
 206
 207         hpfs_lock(dir->i_sb);
 208         if ((err = hpfs_chk_name(name, &len))) {
 209                 if (err == -ENAMETOOLONG) {
 210                         hpfs_unlock(dir->i_sb);
 211                         return ERR_PTR(-ENAMETOOLONG);
 212                 }
 213                 goto end_add;
 214         }
 215
 216         /*
 217          * '.' and '..' will never be passed here.
 218          */
 219
 220         de = map_dirent(dir, hpfs_i(dir)->i_dno, name, len, NULL, &qbh);
 221
 222         /*
 223          * This is not really a bailout, just means file not found.
 224          */
 225
 226         if (!de) goto end;
 227
 228         /*
 229          * Get inode number, what we're after.
 230          */
 231
 232         ino = le32_to_cpu(de->fnode);
 233
 234         /*
 235          * Go find or make an inode.
 236          */
 237
 238         result = iget_locked(dir->i_sb, ino);
 239         if (!result) {
 240                 hpfs_error(dir->i_sb, "hpfs_lookup: can't get inode");
 241                 goto bail1;
 242         }
 243         if (result->i_state & I_NEW) {
 244                 hpfs_init_inode(result);
 245                 if (de->directory)
 246                         hpfs_read_inode(result);
 247                 else if (le32_to_cpu(de->ea_size) && hpfs_sb(dir->i_sb)->sb_eas)
 248                         hpfs_read_inode(result);
 249                 else {
 250                         result->i_mode |= S_IFREG;
 251                         result->i_mode &= ~0111;
 252                         result->i_op = &hpfs_file_iops;
 253                         result->i_fop = &hpfs_file_ops;
 254                         set_nlink(result, 1);
 255                 }
 256                 unlock_new_inode(result);
 257         }
 258         hpfs_result = hpfs_i(result);
 259         if (!de->directory) hpfs_result->i_parent_dir = dir->i_ino;
 260
 261         if (de->has_acl || de->has_xtd_perm) if (!(dir->i_sb->s_flags & MS_RDONLY)) {
 262                 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");
 263                 goto bail1;
 264         }
 265
 266         /*
 267          * Fill in the info from the directory if this is a newly created
 268          * inode.
 269          */
 270
 271         if (!result->i_ctime.tv_sec) {
 272                 if (!(result->i_ctime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(de->creation_date))))
 273                         result->i_ctime.tv_sec = 1;
 274                 result->i_ctime.tv_nsec = 0;
 275                 result->i_mtime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(de->write_date));
 276                 result->i_mtime.tv_nsec = 0;
 277                 result->i_atime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(de->read_date));
 278                 result->i_atime.tv_nsec = 0;
 279                 hpfs_result->i_ea_size = le32_to_cpu(de->ea_size);
 280                 if (!hpfs_result->i_ea_mode && de->read_only)
 281                         result->i_mode &= ~0222;
 282                 if (!de->directory) {
 283                         if (result->i_size == -1) {
 284                                 result->i_size = le32_to_cpu(de->file_size);
 285                                 result->i_data.a_ops = &hpfs_aops;
 286                                 hpfs_i(result)->mmu_private = result->i_size;
 287                         /*
 288                          * i_blocks should count the fnode and any anodes.
 289                          * We count 1 for the fnode and don't bother about
 290                          * anodes -- the disk heads are on the directory band
 291                          * and we want them to stay there.
 292                          */
 293                                 result->i_blocks = 1 + ((result->i_size + 511) >> 9);
 294                         }
 295                 }
 296         }
 297
 298         hpfs_brelse4(&qbh);
 299
 300         /*
 301          * Made it.
 302          */
 303
 304         end:
 305         end_add:
 306         hpfs_unlock(dir->i_sb);
 307         d_add(dentry, result);
 308         return NULL;
 309
 310         /*
 311          * Didn't.
 312          */
 313         bail1:
 314
 315         hpfs_brelse4(&qbh);
 316
 317         /*bail:*/
 318
 319         hpfs_unlock(dir->i_sb);
 320         return ERR_PTR(-ENOENT);
 321 }
 322
 323 const struct file_operations hpfs_dir_ops =
 324 {
 325         .llseek         = hpfs_dir_lseek,
 326         .read           = generic_read_dir,
 327         .iterate        = hpfs_readdir,
 328         .release        = hpfs_dir_release,
 329         .fsync          = hpfs_file_fsync,
 330 };