linux/fs/hpfs/dir.c
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   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
  12static 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
  23static 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        /* 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);
  48ok:
  49        hpfs_unlock(s);
  50        return filp->f_pos = new_off;
  51fail:
  52        mutex_unlock(&i->i_mutex);
  53        /*printk("illegal lseek: %016llx\n", new_off);*/
  54        hpfs_unlock(s);
  55        return -ESPIPE;
  56}
  57
  58static int hpfs_readdir(struct file *filp, void *dirent, filldir_t filldir)
  59{
  60        struct inode *inode = filp->f_path.dentry->d_inode;
  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        }
 172out:
 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
 192struct 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
 319const 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};
 327
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