fs/hppfs/hppfs.c

   1 /*
   2  * Copyright (C) 2002 - 2007 Jeff Dike (jdike@{addtoit,linux.intel}.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include <linux/ctype.h>
   7 #include <linux/dcache.h>
   8 #include <linux/file.h>
   9 #include <linux/fs.h>
  10 #include <linux/init.h>
  11 #include <linux/kernel.h>
  12 #include <linux/list.h>
  13 #include <linux/module.h>
  14 #include <linux/mount.h>
  15 #include <linux/slab.h>
  16 #include <linux/statfs.h>
  17 #include <linux/types.h>
  18 #include <asm/uaccess.h>
  19 #include "os.h"
  20
  21 static struct inode *get_inode(struct super_block *, struct dentry *);
  22
  23 struct hppfs_data {
  24         struct list_head list;
  25         char contents[PAGE_SIZE - sizeof(struct list_head)];
  26 };
  27
  28 struct hppfs_private {
  29         struct file *proc_file;
  30         int host_fd;
  31         loff_t len;
  32         struct hppfs_data *contents;
  33 };
  34
  35 struct hppfs_inode_info {
  36         struct dentry *proc_dentry;
  37         struct inode vfs_inode;
  38 };
  39
  40 static inline struct hppfs_inode_info *HPPFS_I(struct inode *inode)
  41 {
  42         return container_of(inode, struct hppfs_inode_info, vfs_inode);
  43 }
  44
  45 #define HPPFS_SUPER_MAGIC 0xb00000ee
  46
  47 static const struct super_operations hppfs_sbops;
  48
  49 static int is_pid(struct dentry *dentry)
  50 {
  51         struct super_block *sb;
  52         int i;
  53
  54         sb = dentry->d_sb;
  55         if (dentry->d_parent != sb->s_root)
  56                 return 0;
  57
  58         for (i = 0; i < dentry->d_name.len; i++) {
  59                 if (!isdigit(dentry->d_name.name[i]))
  60                         return 0;
  61         }
  62         return 1;
  63 }
  64
  65 static char *dentry_name(struct dentry *dentry, int extra)
  66 {
  67         struct dentry *parent;
  68         char *root, *name;
  69         const char *seg_name;
  70         int len, seg_len;
  71
  72         len = 0;
  73         parent = dentry;
  74         while (parent->d_parent != parent) {
  75                 if (is_pid(parent))
  76                         len += strlen("pid") + 1;
  77                 else len += parent->d_name.len + 1;
  78                 parent = parent->d_parent;
  79         }
  80
  81         root = "proc";
  82         len += strlen(root);
  83         name = kmalloc(len + extra + 1, GFP_KERNEL);
  84         if (name == NULL)
  85                 return NULL;
  86
  87         name[len] = '\0';
  88         parent = dentry;
  89         while (parent->d_parent != parent) {
  90                 if (is_pid(parent)) {
  91                         seg_name = "pid";
  92                         seg_len = strlen("pid");
  93                 }
  94                 else {
  95                         seg_name = parent->d_name.name;
  96                         seg_len = parent->d_name.len;
  97                 }
  98
  99                 len -= seg_len + 1;
 100                 name[len] = '/';
 101                 strncpy(&name[len + 1], seg_name, seg_len);
 102                 parent = parent->d_parent;
 103         }
 104         strncpy(name, root, strlen(root));
 105         return name;
 106 }
 107
 108 static int file_removed(struct dentry *dentry, const char *file)
 109 {
 110         char *host_file;
 111         int extra, fd;
 112
 113         extra = 0;
 114         if (file != NULL)
 115                 extra += strlen(file) + 1;
 116
 117         host_file = dentry_name(dentry, extra + strlen("/remove"));
 118         if (host_file == NULL) {
 119                 printk(KERN_ERR "file_removed : allocation failed\n");
 120                 return -ENOMEM;
 121         }
 122
 123         if (file != NULL) {
 124                 strcat(host_file, "/");
 125                 strcat(host_file, file);
 126         }
 127         strcat(host_file, "/remove");
 128
 129         fd = os_open_file(host_file, of_read(OPENFLAGS()), 0);
 130         kfree(host_file);
 131         if (fd > 0) {
 132                 os_close_file(fd);
 133                 return 1;
 134         }
 135         return 0;
 136 }
 137
 138 static struct dentry *hppfs_lookup(struct inode *ino, struct dentry *dentry,
 139                                    struct nameidata *nd)
 140 {
 141         struct dentry *proc_dentry, *new, *parent;
 142         struct inode *inode;
 143         int err, deleted;
 144
 145         deleted = file_removed(dentry, NULL);
 146         if (deleted < 0)
 147                 return ERR_PTR(deleted);
 148         else if (deleted)
 149                 return ERR_PTR(-ENOENT);
 150
 151         err = -ENOMEM;
 152         parent = HPPFS_I(ino)->proc_dentry;
 153         mutex_lock(&parent->d_inode->i_mutex);
 154         proc_dentry = d_lookup(parent, &dentry->d_name);
 155         if (proc_dentry == NULL) {
 156                 proc_dentry = d_alloc(parent, &dentry->d_name);
 157                 if (proc_dentry == NULL) {
 158                         mutex_unlock(&parent->d_inode->i_mutex);
 159                         goto out;
 160                 }
 161                 new = (*parent->d_inode->i_op->lookup)(parent->d_inode,
 162                                                        proc_dentry, NULL);
 163                 if (new) {
 164                         dput(proc_dentry);
 165                         proc_dentry = new;
 166                 }
 167         }
 168         mutex_unlock(&parent->d_inode->i_mutex);
 169
 170         if (IS_ERR(proc_dentry))
 171                 return proc_dentry;
 172
 173         err = -ENOMEM;
 174         inode = get_inode(ino->i_sb, proc_dentry);
 175         if (!inode)
 176                 goto out_dput;
 177
 178         d_add(dentry, inode);
 179         return NULL;
 180
 181  out_dput:
 182         dput(proc_dentry);
 183  out:
 184         return ERR_PTR(err);
 185 }
 186
 187 static const struct inode_operations hppfs_file_iops = {
 188 };
 189
 190 static ssize_t read_proc(struct file *file, char __user *buf, ssize_t count,
 191                          loff_t *ppos, int is_user)
 192 {
 193         ssize_t (*read)(struct file *, char __user *, size_t, loff_t *);
 194         ssize_t n;
 195
 196         read = file->f_path.dentry->d_inode->i_fop->read;
 197
 198         if (!is_user)
 199                 set_fs(KERNEL_DS);
 200
 201         n = (*read)(file, buf, count, &file->f_pos);
 202
 203         if (!is_user)
 204                 set_fs(USER_DS);
 205
 206         if (ppos)
 207                 *ppos = file->f_pos;
 208         return n;
 209 }
 210
 211 static ssize_t hppfs_read_file(int fd, char __user *buf, ssize_t count)
 212 {
 213         ssize_t n;
 214         int cur, err;
 215         char *new_buf;
 216
 217         n = -ENOMEM;
 218         new_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 219         if (new_buf == NULL) {
 220                 printk(KERN_ERR "hppfs_read_file : kmalloc failed\n");
 221                 goto out;
 222         }
 223         n = 0;
 224         while (count > 0) {
 225                 cur = min_t(ssize_t, count, PAGE_SIZE);
 226                 err = os_read_file(fd, new_buf, cur);
 227                 if (err < 0) {
 228                         printk(KERN_ERR "hppfs_read : read failed, "
 229                                "errno = %d\n", err);
 230                         n = err;
 231                         goto out_free;
 232                 } else if (err == 0)
 233                         break;
 234
 235                 if (copy_to_user(buf, new_buf, err)) {
 236                         n = -EFAULT;
 237                         goto out_free;
 238                 }
 239                 n += err;
 240                 count -= err;
 241         }
 242  out_free:
 243         kfree(new_buf);
 244  out:
 245         return n;
 246 }
 247
 248 static ssize_t hppfs_read(struct file *file, char __user *buf, size_t count,
 249                           loff_t *ppos)
 250 {
 251         struct hppfs_private *hppfs = file->private_data;
 252         struct hppfs_data *data;
 253         loff_t off;
 254         int err;
 255
 256         if (hppfs->contents != NULL) {
 257                 int rem;
 258
 259                 if (*ppos >= hppfs->len)
 260                         return 0;
 261
 262                 data = hppfs->contents;
 263                 off = *ppos;
 264                 while (off >= sizeof(data->contents)) {
 265                         data = list_entry(data->list.next, struct hppfs_data,
 266                                           list);
 267                         off -= sizeof(data->contents);
 268                 }
 269
 270                 if (off + count > hppfs->len)
 271                         count = hppfs->len - off;
 272                 rem = copy_to_user(buf, &data->contents[off], count);
 273                 *ppos += count - rem;
 274                 if (rem > 0)
 275                         return -EFAULT;
 276         } else if (hppfs->host_fd != -1) {
 277                 err = os_seek_file(hppfs->host_fd, *ppos);
 278                 if (err) {
 279                         printk(KERN_ERR "hppfs_read : seek failed, "
 280                                "errno = %d\n", err);
 281                         return err;
 282                 }
 283                 count = hppfs_read_file(hppfs->host_fd, buf, count);
 284                 if (count > 0)
 285                         *ppos += count;
 286         }
 287         else count = read_proc(hppfs->proc_file, buf, count, ppos, 1);
 288
 289         return count;
 290 }
 291
 292 static ssize_t hppfs_write(struct file *file, const char __user *buf,
 293                            size_t len, loff_t *ppos)
 294 {
 295         struct hppfs_private *data = file->private_data;
 296         struct file *proc_file = data->proc_file;
 297         ssize_t (*write)(struct file *, const char __user *, size_t, loff_t *);
 298
 299         write = proc_file->f_path.dentry->d_inode->i_fop->write;
 300         return (*write)(proc_file, buf, len, ppos);
 301 }
 302
 303 static int open_host_sock(char *host_file, int *filter_out)
 304 {
 305         char *end;
 306         int fd;
 307
 308         end = &host_file[strlen(host_file)];
 309         strcpy(end, "/rw");
 310         *filter_out = 1;
 311         fd = os_connect_socket(host_file);
 312         if (fd > 0)
 313                 return fd;
 314
 315         strcpy(end, "/r");
 316         *filter_out = 0;
 317         fd = os_connect_socket(host_file);
 318         return fd;
 319 }
 320
 321 static void free_contents(struct hppfs_data *head)
 322 {
 323         struct hppfs_data *data;
 324         struct list_head *ele, *next;
 325
 326         if (head == NULL)
 327                 return;
 328
 329         list_for_each_safe(ele, next, &head->list) {
 330                 data = list_entry(ele, struct hppfs_data, list);
 331                 kfree(data);
 332         }
 333         kfree(head);
 334 }
 335
 336 static struct hppfs_data *hppfs_get_data(int fd, int filter,
 337                                          struct file *proc_file,
 338                                          struct file *hppfs_file,
 339                                          loff_t *size_out)
 340 {
 341         struct hppfs_data *data, *new, *head;
 342         int n, err;
 343
 344         err = -ENOMEM;
 345         data = kmalloc(sizeof(*data), GFP_KERNEL);
 346         if (data == NULL) {
 347                 printk(KERN_ERR "hppfs_get_data : head allocation failed\n");
 348                 goto failed;
 349         }
 350
 351         INIT_LIST_HEAD(&data->list);
 352
 353         head = data;
 354         *size_out = 0;
 355
 356         if (filter) {
 357                 while ((n = read_proc(proc_file, data->contents,
 358                                       sizeof(data->contents), NULL, 0)) > 0)
 359                         os_write_file(fd, data->contents, n);
 360                 err = os_shutdown_socket(fd, 0, 1);
 361                 if (err) {
 362                         printk(KERN_ERR "hppfs_get_data : failed to shut down "
 363                                "socket\n");
 364                         goto failed_free;
 365                 }
 366         }
 367         while (1) {
 368                 n = os_read_file(fd, data->contents, sizeof(data->contents));
 369                 if (n < 0) {
 370                         err = n;
 371                         printk(KERN_ERR "hppfs_get_data : read failed, "
 372                                "errno = %d\n", err);
 373                         goto failed_free;
 374                 } else if (n == 0)
 375                         break;
 376
 377                 *size_out += n;
 378
 379                 if (n < sizeof(data->contents))
 380                         break;
 381
 382                 new = kmalloc(sizeof(*data), GFP_KERNEL);
 383                 if (new == 0) {
 384                         printk(KERN_ERR "hppfs_get_data : data allocation "
 385                                "failed\n");
 386                         err = -ENOMEM;
 387                         goto failed_free;
 388                 }
 389
 390                 INIT_LIST_HEAD(&new->list);
 391                 list_add(&new->list, &data->list);
 392                 data = new;
 393         }
 394         return head;
 395
 396  failed_free:
 397         free_contents(head);
 398  failed:
 399         return ERR_PTR(err);
 400 }
 401
 402 static struct hppfs_private *hppfs_data(void)
 403 {
 404         struct hppfs_private *data;
 405
 406         data = kmalloc(sizeof(*data), GFP_KERNEL);
 407         if (data == NULL)
 408                 return data;
 409
 410         *data = ((struct hppfs_private ) { .host_fd             = -1,
 411                                            .len                 = -1,
 412                                            .contents            = NULL } );
 413         return data;
 414 }
 415
 416 static int file_mode(int fmode)
 417 {
 418         if (fmode == (FMODE_READ | FMODE_WRITE))
 419                 return O_RDWR;
 420         if (fmode == FMODE_READ)
 421                 return O_RDONLY;
 422         if (fmode == FMODE_WRITE)
 423                 return O_WRONLY;
 424         return 0;
 425 }
 426
 427 static int hppfs_open(struct inode *inode, struct file *file)
 428 {
 429         struct hppfs_private *data;
 430         struct vfsmount *proc_mnt;
 431         struct dentry *proc_dentry;
 432         char *host_file;
 433         int err, fd, type, filter;
 434
 435         err = -ENOMEM;
 436         data = hppfs_data();
 437         if (data == NULL)
 438                 goto out;
 439
 440         host_file = dentry_name(file->f_path.dentry, strlen("/rw"));
 441         if (host_file == NULL)
 442                 goto out_free2;
 443
 444         proc_dentry = HPPFS_I(inode)->proc_dentry;
 445         proc_mnt = inode->i_sb->s_fs_info;
 446
 447         /* XXX This isn't closed anywhere */
 448         data->proc_file = dentry_open(dget(proc_dentry), mntget(proc_mnt),
 449                                       file_mode(file->f_mode));
 450         err = PTR_ERR(data->proc_file);
 451         if (IS_ERR(data->proc_file))
 452                 goto out_free1;
 453
 454         type = os_file_type(host_file);
 455         if (type == OS_TYPE_FILE) {
 456                 fd = os_open_file(host_file, of_read(OPENFLAGS()), 0);
 457                 if (fd >= 0)
 458                         data->host_fd = fd;
 459                 else
 460                         printk(KERN_ERR "hppfs_open : failed to open '%s', "
 461                                "errno = %d\n", host_file, -fd);
 462
 463                 data->contents = NULL;
 464         } else if (type == OS_TYPE_DIR) {
 465                 fd = open_host_sock(host_file, &filter);
 466                 if (fd > 0) {
 467                         data->contents = hppfs_get_data(fd, filter,
 468                                                         data->proc_file,
 469                                                         file, &data->len);
 470                         if (!IS_ERR(data->contents))
 471                                 data->host_fd = fd;
 472                 } else
 473                         printk(KERN_ERR "hppfs_open : failed to open a socket "
 474                                "in '%s', errno = %d\n", host_file, -fd);
 475         }
 476         kfree(host_file);
 477
 478         file->private_data = data;
 479         return 0;
 480
 481  out_free1:
 482         kfree(host_file);
 483  out_free2:
 484         free_contents(data->contents);
 485         kfree(data);
 486  out:
 487         return err;
 488 }
 489
 490 static int hppfs_dir_open(struct inode *inode, struct file *file)
 491 {
 492         struct hppfs_private *data;
 493         struct vfsmount *proc_mnt;
 494         struct dentry *proc_dentry;
 495         int err;
 496
 497         err = -ENOMEM;
 498         data = hppfs_data();
 499         if (data == NULL)
 500                 goto out;
 501
 502         proc_dentry = HPPFS_I(inode)->proc_dentry;
 503         proc_mnt = inode->i_sb->s_fs_info;
 504         data->proc_file = dentry_open(dget(proc_dentry), mntget(proc_mnt),
 505                                       file_mode(file->f_mode));
 506         err = PTR_ERR(data->proc_file);
 507         if (IS_ERR(data->proc_file))
 508                 goto out_free;
 509
 510         file->private_data = data;
 511         return 0;
 512
 513  out_free:
 514         kfree(data);
 515  out:
 516         return err;
 517 }
 518
 519 static loff_t hppfs_llseek(struct file *file, loff_t off, int where)
 520 {
 521         struct hppfs_private *data = file->private_data;
 522         struct file *proc_file = data->proc_file;
 523         loff_t (*llseek)(struct file *, loff_t, int);
 524         loff_t ret;
 525
 526         llseek = proc_file->f_path.dentry->d_inode->i_fop->llseek;
 527         if (llseek != NULL) {
 528                 ret = (*llseek)(proc_file, off, where);
 529                 if (ret < 0)
 530                         return ret;
 531         }
 532
 533         return default_llseek(file, off, where);
 534 }
 535
 536 static const struct file_operations hppfs_file_fops = {
 537         .owner          = NULL,
 538         .llseek         = hppfs_llseek,
 539         .read           = hppfs_read,
 540         .write          = hppfs_write,
 541         .open           = hppfs_open,
 542 };
 543
 544 struct hppfs_dirent {
 545         void *vfs_dirent;
 546         filldir_t filldir;
 547         struct dentry *dentry;
 548 };
 549
 550 static int hppfs_filldir(void *d, const char *name, int size,
 551                          loff_t offset, u64 inode, unsigned int type)
 552 {
 553         struct hppfs_dirent *dirent = d;
 554
 555         if (file_removed(dirent->dentry, name))
 556                 return 0;
 557
 558         return (*dirent->filldir)(dirent->vfs_dirent, name, size, offset,
 559                                   inode, type);
 560 }
 561
 562 static int hppfs_readdir(struct file *file, void *ent, filldir_t filldir)
 563 {
 564         struct hppfs_private *data = file->private_data;
 565         struct file *proc_file = data->proc_file;
 566         int (*readdir)(struct file *, void *, filldir_t);
 567         struct hppfs_dirent dirent = ((struct hppfs_dirent)
 568                                       { .vfs_dirent     = ent,
 569                                         .filldir        = filldir,
 570                                         .dentry         = file->f_path.dentry
 571                                       });
 572         int err;
 573
 574         readdir = proc_file->f_path.dentry->d_inode->i_fop->readdir;
 575
 576         proc_file->f_pos = file->f_pos;
 577         err = (*readdir)(proc_file, &dirent, hppfs_filldir);
 578         file->f_pos = proc_file->f_pos;
 579
 580         return err;
 581 }
 582
 583 static int hppfs_fsync(struct file *file, struct dentry *dentry, int datasync)
 584 {
 585         return 0;
 586 }
 587
 588 static const struct file_operations hppfs_dir_fops = {
 589         .owner          = NULL,
 590         .readdir        = hppfs_readdir,
 591         .open           = hppfs_dir_open,
 592         .fsync          = hppfs_fsync,
 593 };
 594
 595 static int hppfs_statfs(struct dentry *dentry, struct kstatfs *sf)
 596 {
 597         sf->f_blocks = 0;
 598         sf->f_bfree = 0;
 599         sf->f_bavail = 0;
 600         sf->f_files = 0;
 601         sf->f_ffree = 0;
 602         sf->f_type = HPPFS_SUPER_MAGIC;
 603         return 0;
 604 }
 605
 606 static struct inode *hppfs_alloc_inode(struct super_block *sb)
 607 {
 608         struct hppfs_inode_info *hi;
 609
 610         hi = kmalloc(sizeof(*hi), GFP_KERNEL);
 611         if (!hi)
 612                 return NULL;
 613
 614         hi->proc_dentry = NULL;
 615         inode_init_once(&hi->vfs_inode);
 616         return &hi->vfs_inode;
 617 }
 618
 619 void hppfs_delete_inode(struct inode *ino)
 620 {
 621         dput(HPPFS_I(ino)->proc_dentry);
 622         mntput(ino->i_sb->s_fs_info);
 623
 624         clear_inode(ino);
 625 }
 626
 627 static void hppfs_destroy_inode(struct inode *inode)
 628 {
 629         kfree(HPPFS_I(inode));
 630 }
 631
 632 static const struct super_operations hppfs_sbops = {
 633         .alloc_inode    = hppfs_alloc_inode,
 634         .destroy_inode  = hppfs_destroy_inode,
 635         .delete_inode   = hppfs_delete_inode,
 636         .statfs         = hppfs_statfs,
 637 };
 638
 639 static int hppfs_readlink(struct dentry *dentry, char __user *buffer,
 640                           int buflen)
 641 {
 642         struct dentry *proc_dentry;
 643
 644         proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry;
 645         return proc_dentry->d_inode->i_op->readlink(proc_dentry, buffer,
 646                                                     buflen);
 647 }
 648
 649 static void *hppfs_follow_link(struct dentry *dentry, struct nameidata *nd)
 650 {
 651         struct dentry *proc_dentry;
 652
 653         proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry;
 654
 655         return proc_dentry->d_inode->i_op->follow_link(proc_dentry, nd);
 656 }
 657
 658 int hppfs_permission(struct inode *inode, int mask, struct nameidata *nd)
 659 {
 660         return generic_permission(inode, mask, NULL);
 661 }
 662
 663 static const struct inode_operations hppfs_dir_iops = {
 664         .lookup         = hppfs_lookup,
 665         .permission     = hppfs_permission,
 666 };
 667
 668 static const struct inode_operations hppfs_link_iops = {
 669         .readlink       = hppfs_readlink,
 670         .follow_link    = hppfs_follow_link,
 671         .permission     = hppfs_permission,
 672 };
 673
 674 static struct inode *get_inode(struct super_block *sb, struct dentry *dentry)
 675 {
 676         struct inode *proc_ino = dentry->d_inode;
 677         struct inode *inode = new_inode(sb);
 678
 679         if (!inode)
 680                 return ERR_PTR(-ENOMEM);
 681
 682         if (S_ISDIR(dentry->d_inode->i_mode)) {
 683                 inode->i_op = &hppfs_dir_iops;
 684                 inode->i_fop = &hppfs_dir_fops;
 685         } else if (S_ISLNK(dentry->d_inode->i_mode)) {
 686                 inode->i_op = &hppfs_link_iops;
 687                 inode->i_fop = &hppfs_file_fops;
 688         } else {
 689                 inode->i_op = &hppfs_file_iops;
 690                 inode->i_fop = &hppfs_file_fops;
 691         }
 692
 693         HPPFS_I(inode)->proc_dentry = dget(dentry);
 694
 695         inode->i_uid = proc_ino->i_uid;
 696         inode->i_gid = proc_ino->i_gid;
 697         inode->i_atime = proc_ino->i_atime;
 698         inode->i_mtime = proc_ino->i_mtime;
 699         inode->i_ctime = proc_ino->i_ctime;
 700         inode->i_ino = proc_ino->i_ino;
 701         inode->i_mode = proc_ino->i_mode;
 702         inode->i_nlink = proc_ino->i_nlink;
 703         inode->i_size = proc_ino->i_size;
 704         inode->i_blocks = proc_ino->i_blocks;
 705
 706         return inode;
 707 }
 708
 709 static int hppfs_fill_super(struct super_block *sb, void *d, int silent)
 710 {
 711         struct inode *root_inode;
 712         struct vfsmount *proc_mnt;
 713         int err = -ENOENT;
 714
 715         proc_mnt = do_kern_mount("proc", 0, "proc", NULL);
 716         if (IS_ERR(proc_mnt))
 717                 goto out;
 718
 719         sb->s_blocksize = 1024;
 720         sb->s_blocksize_bits = 10;
 721         sb->s_magic = HPPFS_SUPER_MAGIC;
 722         sb->s_op = &hppfs_sbops;
 723         sb->s_fs_info = proc_mnt;
 724
 725         err = -ENOMEM;
 726         root_inode = get_inode(sb, proc_mnt->mnt_sb->s_root);
 727         if (!root_inode)
 728                 goto out_mntput;
 729
 730         sb->s_root = d_alloc_root(root_inode);
 731         if (!sb->s_root)
 732                 goto out_iput;
 733
 734         return 0;
 735
 736  out_iput:
 737         iput(root_inode);
 738  out_mntput:
 739         mntput(proc_mnt);
 740  out:
 741         return(err);
 742 }
 743
 744 static int hppfs_read_super(struct file_system_type *type,
 745                             int flags, const char *dev_name,
 746                             void *data, struct vfsmount *mnt)
 747 {
 748         return get_sb_nodev(type, flags, data, hppfs_fill_super, mnt);
 749 }
 750
 751 static struct file_system_type hppfs_type = {
 752         .owner          = THIS_MODULE,
 753         .name           = "hppfs",
 754         .get_sb         = hppfs_read_super,
 755         .kill_sb        = kill_anon_super,
 756         .fs_flags       = 0,
 757 };
 758
 759 static int __init init_hppfs(void)
 760 {
 761         return register_filesystem(&hppfs_type);
 762 }
 763
 764 static void __exit exit_hppfs(void)
 765 {
 766         unregister_filesystem(&hppfs_type);
 767 }
 768
 769 module_init(init_hppfs)
 770 module_exit(exit_hppfs)
 771 MODULE_LICENSE("GPL");