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         inode_lock(i);
  37         hpfs_lock(s);
  38
  39         /*pr_info("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         if (unlikely(hpfs_add_pos(i, &filp->f_pos) < 0)) {
  48                 hpfs_unlock(s);
  49                 inode_unlock(i);
  50                 return -ENOMEM;
  51         }
  52 ok:
  53         filp->f_pos = new_off;
  54         hpfs_unlock(s);
  55         inode_unlock(i);
  56         return new_off;
  57 fail:
  58         /*pr_warn("illegal lseek: %016llx\n", new_off);*/
  59         hpfs_unlock(s);
  60         inode_unlock(i);
  61         return -ESPIPE;
  62 }
  63
  64 static int hpfs_readdir(struct file *file, struct dir_context *ctx)
  65 {
  66         struct inode *inode = file_inode(file);
  67         struct hpfs_inode_info *hpfs_inode = hpfs_i(inode);
  68         struct quad_buffer_head qbh;
  69         struct hpfs_dirent *de;
  70         int lc;
  71         loff_t next_pos;
  72         unsigned char *tempname;
  73         int c1, c2 = 0;
  74         int ret = 0;
  75
  76         hpfs_lock(inode->i_sb);
  77
  78         if (hpfs_sb(inode->i_sb)->sb_chk) {
  79                 if (hpfs_chk_sectors(inode->i_sb, inode->i_ino, 1, "dir_fnode")) {
  80                         ret = -EFSERROR;
  81                         goto out;
  82                 }
  83                 if (hpfs_chk_sectors(inode->i_sb, hpfs_inode->i_dno, 4, "dir_dnode")) {
  84                         ret = -EFSERROR;
  85                         goto out;
  86                 }
  87         }
  88         if (hpfs_sb(inode->i_sb)->sb_chk >= 2) {
  89                 struct buffer_head *bh;
  90                 struct fnode *fno;
  91                 int e = 0;
  92                 if (!(fno = hpfs_map_fnode(inode->i_sb, inode->i_ino, &bh))) {
  93                         ret = -EIOERROR;
  94                         goto out;
  95                 }
  96                 if (!fnode_is_dir(fno)) {
  97                         e = 1;
  98                         hpfs_error(inode->i_sb, "not a directory, fnode %08lx",
  99                                         (unsigned long)inode->i_ino);
 100                 }
 101                 if (hpfs_inode->i_dno != le32_to_cpu(fno->u.external[0].disk_secno)) {
 102                         e = 1;
 103                         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));
 104                 }
 105                 brelse(bh);
 106                 if (e) {
 107                         ret = -EFSERROR;
 108                         goto out;
 109                 }
 110         }
 111         lc = hpfs_sb(inode->i_sb)->sb_lowercase;
 112         if (ctx->pos == 12) { /* diff -r requires this (note, that diff -r */
 113                 ctx->pos = 13; /* also fails on msdos filesystem in 2.0) */
 114                 goto out;
 115         }
 116         if (ctx->pos == 13) {
 117                 ret = -ENOENT;
 118                 goto out;
 119         }
 120
 121         while (1) {
 122                 again:
 123                 /* This won't work when cycle is longer than number of dirents
 124                    accepted by filldir, but what can I do?
 125                    maybe killall -9 ls helps */
 126                 if (hpfs_sb(inode->i_sb)->sb_chk)
 127                         if (hpfs_stop_cycles(inode->i_sb, ctx->pos, &c1, &c2, "hpfs_readdir")) {
 128                                 ret = -EFSERROR;
 129                                 goto out;
 130                         }
 131                 if (ctx->pos == 12)
 132                         goto out;
 133                 if (ctx->pos == 3 || ctx->pos == 4 || ctx->pos == 5) {
 134                         pr_err("pos==%d\n", (int)ctx->pos);
 135                         goto out;
 136                 }
 137                 if (ctx->pos == 0) {
 138                         if (!dir_emit_dot(file, ctx))
 139                                 goto out;
 140                         ctx->pos = 11;
 141                 }
 142                 if (ctx->pos == 11) {
 143                         if (!dir_emit(ctx, "..", 2, hpfs_inode->i_parent_dir, DT_DIR))
 144                                 goto out;
 145                         ctx->pos = 1;
 146                 }
 147                 if (ctx->pos == 1) {
 148                         ret = hpfs_add_pos(inode, &file->f_pos);
 149                         if (unlikely(ret < 0))
 150                                 goto out;
 151                         ctx->pos = ((loff_t) hpfs_de_as_down_as_possible(inode->i_sb, hpfs_inode->i_dno) << 4) + 1;
 152                         file->f_version = inode->i_version;
 153                 }
 154                 next_pos = ctx->pos;
 155                 if (!(de = map_pos_dirent(inode, &next_pos, &qbh))) {
 156                         ctx->pos = next_pos;
 157                         ret = -EIOERROR;
 158                         goto out;
 159                 }
 160                 if (de->first || de->last) {
 161                         if (hpfs_sb(inode->i_sb)->sb_chk) {
 162                                 if (de->first && !de->last && (de->namelen != 2
 163                                     || de ->name[0] != 1 || de->name[1] != 1))
 164                                         hpfs_error(inode->i_sb, "hpfs_readdir: bad ^A^A entry; pos = %08lx", (unsigned long)ctx->pos);
 165                                 if (de->last && (de->namelen != 1 || de ->name[0] != 255))
 166                                         hpfs_error(inode->i_sb, "hpfs_readdir: bad \\377 entry; pos = %08lx", (unsigned long)ctx->pos);
 167                         }
 168                         hpfs_brelse4(&qbh);
 169                         ctx->pos = next_pos;
 170                         goto again;
 171                 }
 172                 tempname = hpfs_translate_name(inode->i_sb, de->name, de->namelen, lc, de->not_8x3);
 173                 if (!dir_emit(ctx, tempname, de->namelen, le32_to_cpu(de->fnode), DT_UNKNOWN)) {
 174                         if (tempname != de->name) kfree(tempname);
 175                         hpfs_brelse4(&qbh);
 176                         goto out;
 177                 }
 178                 ctx->pos = next_pos;
 179                 if (tempname != de->name) kfree(tempname);
 180                 hpfs_brelse4(&qbh);
 181         }
 182 out:
 183         hpfs_unlock(inode->i_sb);
 184         return ret;
 185 }
 186
 187 /*
 188  * lookup.  Search the specified directory for the specified name, set
 189  * *result to the corresponding inode.
 190  *
 191  * lookup uses the inode number to tell read_inode whether it is reading
 192  * the inode of a directory or a file -- file ino's are odd, directory
 193  * ino's are even.  read_inode avoids i/o for file inodes; everything
 194  * needed is up here in the directory.  (And file fnodes are out in
 195  * the boondocks.)
 196  *
 197  *    - M.P.: this is over, sometimes we've got to read file's fnode for eas
 198  *            inode numbers are just fnode sector numbers; iget lock is used
 199  *            to tell read_inode to read fnode or not.
 200  */
 201
 202 struct dentry *hpfs_lookup(struct inode *dir, struct dentry *dentry, unsigned int flags)
 203 {
 204         const unsigned char *name = dentry->d_name.name;
 205         unsigned len = dentry->d_name.len;
 206         struct quad_buffer_head qbh;
 207         struct hpfs_dirent *de;
 208         ino_t ino;
 209         int err;
 210         struct inode *result = NULL;
 211         struct hpfs_inode_info *hpfs_result;
 212
 213         hpfs_lock(dir->i_sb);
 214         if ((err = hpfs_chk_name(name, &len))) {
 215                 if (err == -ENAMETOOLONG) {
 216                         hpfs_unlock(dir->i_sb);
 217                         return ERR_PTR(-ENAMETOOLONG);
 218                 }
 219                 goto end_add;
 220         }
 221
 222         /*
 223          * '.' and '..' will never be passed here.
 224          */
 225
 226         de = map_dirent(dir, hpfs_i(dir)->i_dno, name, len, NULL, &qbh);
 227
 228         /*
 229          * This is not really a bailout, just means file not found.
 230          */
 231
 232         if (!de) goto end;
 233
 234         /*
 235          * Get inode number, what we're after.
 236          */
 237
 238         ino = le32_to_cpu(de->fnode);
 239
 240         /*
 241          * Go find or make an inode.
 242          */
 243
 244         result = iget_locked(dir->i_sb, ino);
 245         if (!result) {
 246                 hpfs_error(dir->i_sb, "hpfs_lookup: can't get inode");
 247                 goto bail1;
 248         }
 249         if (result->i_state & I_NEW) {
 250                 hpfs_init_inode(result);
 251                 if (de->directory)
 252                         hpfs_read_inode(result);
 253                 else if (le32_to_cpu(de->ea_size) && hpfs_sb(dir->i_sb)->sb_eas)
 254                         hpfs_read_inode(result);
 255                 else {
 256                         result->i_mode |= S_IFREG;
 257                         result->i_mode &= ~0111;
 258                         result->i_op = &hpfs_file_iops;
 259                         result->i_fop = &hpfs_file_ops;
 260                         set_nlink(result, 1);
 261                 }
 262                 unlock_new_inode(result);
 263         }
 264         hpfs_result = hpfs_i(result);
 265         if (!de->directory) hpfs_result->i_parent_dir = dir->i_ino;
 266
 267         if (de->has_acl || de->has_xtd_perm) if (!(dir->i_sb->s_flags & MS_RDONLY)) {
 268                 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");
 269                 goto bail1;
 270         }
 271
 272         /*
 273          * Fill in the info from the directory if this is a newly created
 274          * inode.
 275          */
 276
 277         if (!result->i_ctime.tv_sec) {
 278                 if (!(result->i_ctime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(de->creation_date))))
 279                         result->i_ctime.tv_sec = 1;
 280                 result->i_ctime.tv_nsec = 0;
 281                 result->i_mtime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(de->write_date));
 282                 result->i_mtime.tv_nsec = 0;
 283                 result->i_atime.tv_sec = local_to_gmt(dir->i_sb, le32_to_cpu(de->read_date));
 284                 result->i_atime.tv_nsec = 0;
 285                 hpfs_result->i_ea_size = le32_to_cpu(de->ea_size);
 286                 if (!hpfs_result->i_ea_mode && de->read_only)
 287                         result->i_mode &= ~0222;
 288                 if (!de->directory) {
 289                         if (result->i_size == -1) {
 290                                 result->i_size = le32_to_cpu(de->file_size);
 291                                 result->i_data.a_ops = &hpfs_aops;
 292                                 hpfs_i(result)->mmu_private = result->i_size;
 293                         /*
 294                          * i_blocks should count the fnode and any anodes.
 295                          * We count 1 for the fnode and don't bother about
 296                          * anodes -- the disk heads are on the directory band
 297                          * and we want them to stay there.
 298                          */
 299                                 result->i_blocks = 1 + ((result->i_size + 511) >> 9);
 300                         }
 301                 }
 302         }
 303
 304         hpfs_brelse4(&qbh);
 305
 306         /*
 307          * Made it.
 308          */
 309
 310         end:
 311         end_add:
 312         hpfs_unlock(dir->i_sb);
 313         d_add(dentry, result);
 314         return NULL;
 315
 316         /*
 317          * Didn't.
 318          */
 319         bail1:
 320
 321         hpfs_brelse4(&qbh);
 322
 323         /*bail:*/
 324
 325         hpfs_unlock(dir->i_sb);
 326         return ERR_PTR(-ENOENT);
 327 }
 328
 329 const struct file_operations hpfs_dir_ops =
 330 {
 331         .llseek         = hpfs_dir_lseek,
 332         .read           = generic_read_dir,
 333         .iterate_shared = hpfs_readdir,
 334         .release        = hpfs_dir_release,
 335         .fsync          = hpfs_file_fsync,
 336         .unlocked_ioctl = hpfs_ioctl,
 337 };