LXR linux/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
  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 = 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        }
  52ok:
  53        filp->f_pos = new_off;
  54        hpfs_unlock(s);
  55        inode_unlock(i);
  56        return new_off;
  57fail:
  58        /*pr_warn("illegal lseek: %016llx\n", new_off);*/
  59        hpfs_unlock(s);
  60        inode_unlock(i);
  61        return -ESPIPE;
  62}
  63
  64static 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        }
 182out:
 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
 202struct 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
 329const 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};
 338