fs/hppfs/hppfs_kern.c

   1 /*
   2  * Copyright (C) 2002 Jeff Dike (jdike@karaya.com)
   3  * Licensed under the GPL
   4  */
   5
   6 #include <linux/fs.h>
   7 #include <linux/file.h>
   8 #include <linux/module.h>
   9 #include <linux/init.h>
  10 #include <linux/slab.h>
  11 #include <linux/list.h>
  12 #include <linux/kernel.h>
  13 #include <linux/ctype.h>
  14 #include <linux/dcache.h>
  15 #include <linux/statfs.h>
  16 #include <asm/uaccess.h>
  17 #include <asm/fcntl.h>
  18 #include "os.h"
  19
  20 static int init_inode(struct inode *inode, struct dentry *dentry);
  21
  22 struct hppfs_data {
  23         struct list_head list;
  24         char contents[PAGE_SIZE - sizeof(struct list_head)];
  25 };
  26
  27 struct hppfs_private {
  28         struct file *proc_file;
  29         int host_fd;
  30         loff_t len;
  31         struct hppfs_data *contents;
  32 };
  33
  34 struct hppfs_inode_info {
  35         struct dentry *proc_dentry;
  36         struct inode vfs_inode;
  37 };
  38
  39 static inline struct hppfs_inode_info *HPPFS_I(struct inode *inode)
  40 {
  41         return container_of(inode, struct hppfs_inode_info, vfs_inode);
  42 }
  43
  44 #define HPPFS_SUPER_MAGIC 0xb00000ee
  45
  46 static const struct super_operations hppfs_sbops;
  47
  48 static int is_pid(struct dentry *dentry)
  49 {
  50         struct super_block *sb;
  51         int i;
  52
  53         sb = dentry->d_sb;
  54         if((sb->s_op != &hppfs_sbops) || (dentry->d_parent != sb->s_root))
  55                 return(0);
  56
  57         for(i = 0; i < dentry->d_name.len; i++){
  58                 if(!isdigit(dentry->d_name.name[i]))
  59                         return(0);
  60         }
  61         return(1);
  62 }
  63
  64 static char *dentry_name(struct dentry *dentry, int extra)
  65 {
  66         struct dentry *parent;
  67         char *root, *name;
  68         const char *seg_name;
  69         int len, seg_len;
  70
  71         len = 0;
  72         parent = dentry;
  73         while(parent->d_parent != parent){
  74                 if(is_pid(parent))
  75                         len += strlen("pid") + 1;
  76                 else len += parent->d_name.len + 1;
  77                 parent = parent->d_parent;
  78         }
  79
  80         root = "proc";
  81         len += strlen(root);
  82         name = kmalloc(len + extra + 1, GFP_KERNEL);
  83         if(name == NULL) return(NULL);
  84
  85         name[len] = '\0';
  86         parent = dentry;
  87         while(parent->d_parent != parent){
  88                 if(is_pid(parent)){
  89                         seg_name = "pid";
  90                         seg_len = strlen("pid");
  91                 }
  92                 else {
  93                         seg_name = parent->d_name.name;
  94                         seg_len = parent->d_name.len;
  95                 }
  96
  97                 len -= seg_len + 1;
  98                 name[len] = '/';
  99                 strncpy(&name[len + 1], seg_name, seg_len);
 100                 parent = parent->d_parent;
 101         }
 102         strncpy(name, root, strlen(root));
 103         return(name);
 104 }
 105
 106 struct dentry_operations hppfs_dentry_ops = {
 107 };
 108
 109 static int file_removed(struct dentry *dentry, const char *file)
 110 {
 111         char *host_file;
 112         int extra, fd;
 113
 114         extra = 0;
 115         if(file != NULL) extra += strlen(file) + 1;
 116
 117         host_file = dentry_name(dentry, extra + strlen("/remove"));
 118         if(host_file == NULL){
 119                 printk("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 void hppfs_read_inode(struct inode *ino)
 139 {
 140         struct inode *proc_ino;
 141
 142         if(HPPFS_I(ino)->proc_dentry == NULL)
 143                 return;
 144
 145         proc_ino = HPPFS_I(ino)->proc_dentry->d_inode;
 146         ino->i_uid = proc_ino->i_uid;
 147         ino->i_gid = proc_ino->i_gid;
 148         ino->i_atime = proc_ino->i_atime;
 149         ino->i_mtime = proc_ino->i_mtime;
 150         ino->i_ctime = proc_ino->i_ctime;
 151         ino->i_ino = proc_ino->i_ino;
 152         ino->i_mode = proc_ino->i_mode;
 153         ino->i_nlink = proc_ino->i_nlink;
 154         ino->i_size = proc_ino->i_size;
 155         ino->i_blocks = proc_ino->i_blocks;
 156 }
 157
 158 static struct dentry *hppfs_lookup(struct inode *ino, struct dentry *dentry,
 159                                   struct nameidata *nd)
 160 {
 161         struct dentry *proc_dentry, *new, *parent;
 162         struct inode *inode;
 163         int err, deleted;
 164
 165         deleted = file_removed(dentry, NULL);
 166         if(deleted < 0)
 167                 return(ERR_PTR(deleted));
 168         else if(deleted)
 169                 return(ERR_PTR(-ENOENT));
 170
 171         err = -ENOMEM;
 172         parent = HPPFS_I(ino)->proc_dentry;
 173         mutex_lock(&parent->d_inode->i_mutex);
 174         proc_dentry = d_lookup(parent, &dentry->d_name);
 175         if(proc_dentry == NULL){
 176                 proc_dentry = d_alloc(parent, &dentry->d_name);
 177                 if(proc_dentry == NULL){
 178                         mutex_unlock(&parent->d_inode->i_mutex);
 179                         goto out;
 180                 }
 181                 new = (*parent->d_inode->i_op->lookup)(parent->d_inode,
 182                                                        proc_dentry, NULL);
 183                 if(new){
 184                         dput(proc_dentry);
 185                         proc_dentry = new;
 186                 }
 187         }
 188         mutex_unlock(&parent->d_inode->i_mutex);
 189
 190         if(IS_ERR(proc_dentry))
 191                 return(proc_dentry);
 192
 193         inode = iget(ino->i_sb, 0);
 194         if(inode == NULL)
 195                 goto out_dput;
 196
 197         err = init_inode(inode, proc_dentry);
 198         if(err)
 199                 goto out_put;
 200
 201         hppfs_read_inode(inode);
 202
 203         d_add(dentry, inode);
 204         dentry->d_op = &hppfs_dentry_ops;
 205         return(NULL);
 206
 207  out_put:
 208         iput(inode);
 209  out_dput:
 210         dput(proc_dentry);
 211  out:
 212         return(ERR_PTR(err));
 213 }
 214
 215 static const struct inode_operations hppfs_file_iops = {
 216 };
 217
 218 static ssize_t read_proc(struct file *file, char __user *buf, ssize_t count,
 219                          loff_t *ppos, int is_user)
 220 {
 221         ssize_t (*read)(struct file *, char __user *, size_t, loff_t *);
 222         ssize_t n;
 223
 224         read = file->f_path.dentry->d_inode->i_fop->read;
 225
 226         if(!is_user)
 227                 set_fs(KERNEL_DS);
 228
 229         n = (*read)(file, buf, count, &file->f_pos);
 230
 231         if(!is_user)
 232                 set_fs(USER_DS);
 233
 234         if(ppos) *ppos = file->f_pos;
 235         return n;
 236 }
 237
 238 static ssize_t hppfs_read_file(int fd, char __user *buf, ssize_t count)
 239 {
 240         ssize_t n;
 241         int cur, err;
 242         char *new_buf;
 243
 244         n = -ENOMEM;
 245         new_buf = kmalloc(PAGE_SIZE, GFP_KERNEL);
 246         if(new_buf == NULL){
 247                 printk("hppfs_read_file : kmalloc failed\n");
 248                 goto out;
 249         }
 250         n = 0;
 251         while(count > 0){
 252                 cur = min_t(ssize_t, count, PAGE_SIZE);
 253                 err = os_read_file(fd, new_buf, cur);
 254                 if(err < 0){
 255                         printk("hppfs_read : read failed, errno = %d\n",
 256                                err);
 257                         n = err;
 258                         goto out_free;
 259                 }
 260                 else if(err == 0)
 261                         break;
 262
 263                 if(copy_to_user(buf, new_buf, err)){
 264                         n = -EFAULT;
 265                         goto out_free;
 266                 }
 267                 n += err;
 268                 count -= err;
 269         }
 270  out_free:
 271         kfree(new_buf);
 272  out:
 273         return n;
 274 }
 275
 276 static ssize_t hppfs_read(struct file *file, char __user *buf, size_t count,
 277                           loff_t *ppos)
 278 {
 279         struct hppfs_private *hppfs = file->private_data;
 280         struct hppfs_data *data;
 281         loff_t off;
 282         int err;
 283
 284         if(hppfs->contents != NULL){
 285                 if(*ppos >= hppfs->len) return(0);
 286
 287                 data = hppfs->contents;
 288                 off = *ppos;
 289                 while(off >= sizeof(data->contents)){
 290                         data = list_entry(data->list.next, struct hppfs_data,
 291                                           list);
 292                         off -= sizeof(data->contents);
 293                 }
 294
 295                 if(off + count > hppfs->len)
 296                         count = hppfs->len - off;
 297                 copy_to_user(buf, &data->contents[off], count);
 298                 *ppos += count;
 299         }
 300         else if(hppfs->host_fd != -1){
 301                 err = os_seek_file(hppfs->host_fd, *ppos);
 302                 if(err){
 303                         printk("hppfs_read : seek failed, errno = %d\n", err);
 304                         return(err);
 305                 }
 306                 count = hppfs_read_file(hppfs->host_fd, buf, count);
 307                 if(count > 0)
 308                         *ppos += count;
 309         }
 310         else count = read_proc(hppfs->proc_file, buf, count, ppos, 1);
 311
 312         return(count);
 313 }
 314
 315 static ssize_t hppfs_write(struct file *file, const char __user *buf, size_t len,
 316                            loff_t *ppos)
 317 {
 318         struct hppfs_private *data = file->private_data;
 319         struct file *proc_file = data->proc_file;
 320         ssize_t (*write)(struct file *, const char __user *, size_t, loff_t *);
 321         int err;
 322
 323         write = proc_file->f_path.dentry->d_inode->i_fop->write;
 324
 325         proc_file->f_pos = file->f_pos;
 326         err = (*write)(proc_file, buf, len, &proc_file->f_pos);
 327         file->f_pos = proc_file->f_pos;
 328
 329         return(err);
 330 }
 331
 332 static int open_host_sock(char *host_file, int *filter_out)
 333 {
 334         char *end;
 335         int fd;
 336
 337         end = &host_file[strlen(host_file)];
 338         strcpy(end, "/rw");
 339         *filter_out = 1;
 340         fd = os_connect_socket(host_file);
 341         if(fd > 0)
 342                 return(fd);
 343
 344         strcpy(end, "/r");
 345         *filter_out = 0;
 346         fd = os_connect_socket(host_file);
 347         return(fd);
 348 }
 349
 350 static void free_contents(struct hppfs_data *head)
 351 {
 352         struct hppfs_data *data;
 353         struct list_head *ele, *next;
 354
 355         if(head == NULL) return;
 356
 357         list_for_each_safe(ele, next, &head->list){
 358                 data = list_entry(ele, struct hppfs_data, list);
 359                 kfree(data);
 360         }
 361         kfree(head);
 362 }
 363
 364 static struct hppfs_data *hppfs_get_data(int fd, int filter,
 365                                          struct file *proc_file,
 366                                          struct file *hppfs_file,
 367                                          loff_t *size_out)
 368 {
 369         struct hppfs_data *data, *new, *head;
 370         int n, err;
 371
 372         err = -ENOMEM;
 373         data = kmalloc(sizeof(*data), GFP_KERNEL);
 374         if(data == NULL){
 375                 printk("hppfs_get_data : head allocation failed\n");
 376                 goto failed;
 377         }
 378
 379         INIT_LIST_HEAD(&data->list);
 380
 381         head = data;
 382         *size_out = 0;
 383
 384         if(filter){
 385                 while((n = read_proc(proc_file, data->contents,
 386                                      sizeof(data->contents), NULL, 0)) > 0)
 387                         os_write_file(fd, data->contents, n);
 388                 err = os_shutdown_socket(fd, 0, 1);
 389                 if(err){
 390                         printk("hppfs_get_data : failed to shut down "
 391                                "socket\n");
 392                         goto failed_free;
 393                 }
 394         }
 395         while(1){
 396                 n = os_read_file(fd, data->contents, sizeof(data->contents));
 397                 if(n < 0){
 398                         err = n;
 399                         printk("hppfs_get_data : read failed, errno = %d\n",
 400                                err);
 401                         goto failed_free;
 402                 }
 403                 else if(n == 0)
 404                         break;
 405
 406                 *size_out += n;
 407
 408                 if(n < sizeof(data->contents))
 409                         break;
 410
 411                 new = kmalloc(sizeof(*data), GFP_KERNEL);
 412                 if(new == 0){
 413                         printk("hppfs_get_data : data allocation failed\n");
 414                         err = -ENOMEM;
 415                         goto failed_free;
 416                 }
 417
 418                 INIT_LIST_HEAD(&new->list);
 419                 list_add(&new->list, &data->list);
 420                 data = new;
 421         }
 422         return(head);
 423
 424  failed_free:
 425         free_contents(head);
 426  failed:
 427         return(ERR_PTR(err));
 428 }
 429
 430 static struct hppfs_private *hppfs_data(void)
 431 {
 432         struct hppfs_private *data;
 433
 434         data = kmalloc(sizeof(*data), GFP_KERNEL);
 435         if(data == NULL)
 436                 return(data);
 437
 438         *data = ((struct hppfs_private ) { .host_fd             = -1,
 439                                            .len                 = -1,
 440                                            .contents            = NULL } );
 441         return(data);
 442 }
 443
 444 static int file_mode(int fmode)
 445 {
 446         if(fmode == (FMODE_READ | FMODE_WRITE))
 447                 return(O_RDWR);
 448         if(fmode == FMODE_READ)
 449                 return(O_RDONLY);
 450         if(fmode == FMODE_WRITE)
 451                 return(O_WRONLY);
 452         return(0);
 453 }
 454
 455 static int hppfs_open(struct inode *inode, struct file *file)
 456 {
 457         struct hppfs_private *data;
 458         struct dentry *proc_dentry;
 459         char *host_file;
 460         int err, fd, type, filter;
 461
 462         err = -ENOMEM;
 463         data = hppfs_data();
 464         if(data == NULL)
 465                 goto out;
 466
 467         host_file = dentry_name(file->f_path.dentry, strlen("/rw"));
 468         if(host_file == NULL)
 469                 goto out_free2;
 470
 471         proc_dentry = HPPFS_I(inode)->proc_dentry;
 472
 473         /* XXX This isn't closed anywhere */
 474         data->proc_file = dentry_open(dget(proc_dentry), NULL,
 475                                       file_mode(file->f_mode));
 476         err = PTR_ERR(data->proc_file);
 477         if(IS_ERR(data->proc_file))
 478                 goto out_free1;
 479
 480         type = os_file_type(host_file);
 481         if(type == OS_TYPE_FILE){
 482                 fd = os_open_file(host_file, of_read(OPENFLAGS()), 0);
 483                 if(fd >= 0)
 484                         data->host_fd = fd;
 485                 else printk("hppfs_open : failed to open '%s', errno = %d\n",
 486                             host_file, -fd);
 487
 488                 data->contents = NULL;
 489         }
 490         else if(type == OS_TYPE_DIR){
 491                 fd = open_host_sock(host_file, &filter);
 492                 if(fd > 0){
 493                         data->contents = hppfs_get_data(fd, filter,
 494                                                         data->proc_file,
 495                                                         file, &data->len);
 496                         if(!IS_ERR(data->contents))
 497                                 data->host_fd = fd;
 498                 }
 499                 else printk("hppfs_open : failed to open a socket in "
 500                             "'%s', errno = %d\n", host_file, -fd);
 501         }
 502         kfree(host_file);
 503
 504         file->private_data = data;
 505         return(0);
 506
 507  out_free1:
 508         kfree(host_file);
 509  out_free2:
 510         free_contents(data->contents);
 511         kfree(data);
 512  out:
 513         return(err);
 514 }
 515
 516 static int hppfs_dir_open(struct inode *inode, struct file *file)
 517 {
 518         struct hppfs_private *data;
 519         struct dentry *proc_dentry;
 520         int err;
 521
 522         err = -ENOMEM;
 523         data = hppfs_data();
 524         if(data == NULL)
 525                 goto out;
 526
 527         proc_dentry = HPPFS_I(inode)->proc_dentry;
 528         data->proc_file = dentry_open(dget(proc_dentry), NULL,
 529                                       file_mode(file->f_mode));
 530         err = PTR_ERR(data->proc_file);
 531         if(IS_ERR(data->proc_file))
 532                 goto out_free;
 533
 534         file->private_data = data;
 535         return(0);
 536
 537  out_free:
 538         kfree(data);
 539  out:
 540         return(err);
 541 }
 542
 543 static loff_t hppfs_llseek(struct file *file, loff_t off, int where)
 544 {
 545         struct hppfs_private *data = file->private_data;
 546         struct file *proc_file = data->proc_file;
 547         loff_t (*llseek)(struct file *, loff_t, int);
 548         loff_t ret;
 549
 550         llseek = proc_file->f_path.dentry->d_inode->i_fop->llseek;
 551         if(llseek != NULL){
 552                 ret = (*llseek)(proc_file, off, where);
 553                 if(ret < 0)
 554                         return(ret);
 555         }
 556
 557         return(default_llseek(file, off, where));
 558 }
 559
 560 static const struct file_operations hppfs_file_fops = {
 561         .owner          = NULL,
 562         .llseek         = hppfs_llseek,
 563         .read           = hppfs_read,
 564         .write          = hppfs_write,
 565         .open           = hppfs_open,
 566 };
 567
 568 struct hppfs_dirent {
 569         void *vfs_dirent;
 570         filldir_t filldir;
 571         struct dentry *dentry;
 572 };
 573
 574 static int hppfs_filldir(void *d, const char *name, int size,
 575                          loff_t offset, u64 inode, unsigned int type)
 576 {
 577         struct hppfs_dirent *dirent = d;
 578
 579         if(file_removed(dirent->dentry, name))
 580                 return(0);
 581
 582         return((*dirent->filldir)(dirent->vfs_dirent, name, size, offset,
 583                                   inode, type));
 584 }
 585
 586 static int hppfs_readdir(struct file *file, void *ent, filldir_t filldir)
 587 {
 588         struct hppfs_private *data = file->private_data;
 589         struct file *proc_file = data->proc_file;
 590         int (*readdir)(struct file *, void *, filldir_t);
 591         struct hppfs_dirent dirent = ((struct hppfs_dirent)
 592                                       { .vfs_dirent     = ent,
 593                                         .filldir        = filldir,
 594                                         .dentry         = file->f_path.dentry } );
 595         int err;
 596
 597         readdir = proc_file->f_path.dentry->d_inode->i_fop->readdir;
 598
 599         proc_file->f_pos = file->f_pos;
 600         err = (*readdir)(proc_file, &dirent, hppfs_filldir);
 601         file->f_pos = proc_file->f_pos;
 602
 603         return(err);
 604 }
 605
 606 static int hppfs_fsync(struct file *file, struct dentry *dentry, int datasync)
 607 {
 608         return(0);
 609 }
 610
 611 static const struct file_operations hppfs_dir_fops = {
 612         .owner          = NULL,
 613         .readdir        = hppfs_readdir,
 614         .open           = hppfs_dir_open,
 615         .fsync          = hppfs_fsync,
 616 };
 617
 618 static int hppfs_statfs(struct dentry *dentry, struct kstatfs *sf)
 619 {
 620         sf->f_blocks = 0;
 621         sf->f_bfree = 0;
 622         sf->f_bavail = 0;
 623         sf->f_files = 0;
 624         sf->f_ffree = 0;
 625         sf->f_type = HPPFS_SUPER_MAGIC;
 626         return(0);
 627 }
 628
 629 static struct inode *hppfs_alloc_inode(struct super_block *sb)
 630 {
 631         struct hppfs_inode_info *hi;
 632
 633         hi = kmalloc(sizeof(*hi), GFP_KERNEL);
 634         if(hi == NULL)
 635                 return(NULL);
 636
 637         *hi = ((struct hppfs_inode_info) { .proc_dentry = NULL });
 638         inode_init_once(&hi->vfs_inode);
 639         return(&hi->vfs_inode);
 640 }
 641
 642 void hppfs_delete_inode(struct inode *ino)
 643 {
 644         clear_inode(ino);
 645 }
 646
 647 static void hppfs_destroy_inode(struct inode *inode)
 648 {
 649         kfree(HPPFS_I(inode));
 650 }
 651
 652 static const struct super_operations hppfs_sbops = {
 653         .alloc_inode    = hppfs_alloc_inode,
 654         .destroy_inode  = hppfs_destroy_inode,
 655         .read_inode     = hppfs_read_inode,
 656         .delete_inode   = hppfs_delete_inode,
 657         .statfs         = hppfs_statfs,
 658 };
 659
 660 static int hppfs_readlink(struct dentry *dentry, char __user *buffer, int buflen)
 661 {
 662         struct file *proc_file;
 663         struct dentry *proc_dentry;
 664         int ret;
 665
 666         proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry;
 667         proc_file = dentry_open(dget(proc_dentry), NULL, O_RDONLY);
 668         if (IS_ERR(proc_file))
 669                 return PTR_ERR(proc_file);
 670
 671         ret = proc_dentry->d_inode->i_op->readlink(proc_dentry, buffer, buflen);
 672
 673         fput(proc_file);
 674
 675         return ret;
 676 }
 677
 678 static void* hppfs_follow_link(struct dentry *dentry, struct nameidata *nd)
 679 {
 680         struct file *proc_file;
 681         struct dentry *proc_dentry;
 682         void *ret;
 683
 684         proc_dentry = HPPFS_I(dentry->d_inode)->proc_dentry;
 685         proc_file = dentry_open(dget(proc_dentry), NULL, O_RDONLY);
 686         if (IS_ERR(proc_file))
 687                 return proc_file;
 688
 689         ret = proc_dentry->d_inode->i_op->follow_link(proc_dentry, nd);
 690
 691         fput(proc_file);
 692
 693         return ret;
 694 }
 695
 696 static const struct inode_operations hppfs_dir_iops = {
 697         .lookup         = hppfs_lookup,
 698 };
 699
 700 static const struct inode_operations hppfs_link_iops = {
 701         .readlink       = hppfs_readlink,
 702         .follow_link    = hppfs_follow_link,
 703 };
 704
 705 static int init_inode(struct inode *inode, struct dentry *dentry)
 706 {
 707         if(S_ISDIR(dentry->d_inode->i_mode)){
 708                 inode->i_op = &hppfs_dir_iops;
 709                 inode->i_fop = &hppfs_dir_fops;
 710         }
 711         else if(S_ISLNK(dentry->d_inode->i_mode)){
 712                 inode->i_op = &hppfs_link_iops;
 713                 inode->i_fop = &hppfs_file_fops;
 714         }
 715         else {
 716                 inode->i_op = &hppfs_file_iops;
 717                 inode->i_fop = &hppfs_file_fops;
 718         }
 719
 720         HPPFS_I(inode)->proc_dentry = dentry;
 721
 722         return(0);
 723 }
 724
 725 static int hppfs_fill_super(struct super_block *sb, void *d, int silent)
 726 {
 727         struct inode *root_inode;
 728         struct file_system_type *procfs;
 729         struct super_block *proc_sb;
 730         int err;
 731
 732         err = -ENOENT;
 733         procfs = get_fs_type("proc");
 734         if(procfs == NULL)
 735                 goto out;
 736
 737         if(list_empty(&procfs->fs_supers))
 738                 goto out;
 739
 740         proc_sb = list_entry(procfs->fs_supers.next, struct super_block,
 741                              s_instances);
 742
 743         sb->s_blocksize = 1024;
 744         sb->s_blocksize_bits = 10;
 745         sb->s_magic = HPPFS_SUPER_MAGIC;
 746         sb->s_op = &hppfs_sbops;
 747
 748         root_inode = iget(sb, 0);
 749         if(root_inode == NULL)
 750                 goto out;
 751
 752         err = init_inode(root_inode, proc_sb->s_root);
 753         if(err)
 754                 goto out_put;
 755
 756         err = -ENOMEM;
 757         sb->s_root = d_alloc_root(root_inode);
 758         if(sb->s_root == NULL)
 759                 goto out_put;
 760
 761         hppfs_read_inode(root_inode);
 762
 763         return(0);
 764
 765  out_put:
 766         iput(root_inode);
 767  out:
 768         return(err);
 769 }
 770
 771 static int hppfs_read_super(struct file_system_type *type,
 772                             int flags, const char *dev_name,
 773                             void *data, struct vfsmount *mnt)
 774 {
 775         return get_sb_nodev(type, flags, data, hppfs_fill_super, mnt);
 776 }
 777
 778 static struct file_system_type hppfs_type = {
 779         .owner          = THIS_MODULE,
 780         .name           = "hppfs",
 781         .get_sb         = hppfs_read_super,
 782         .kill_sb        = kill_anon_super,
 783         .fs_flags       = 0,
 784 };
 785
 786 static int __init init_hppfs(void)
 787 {
 788         return(register_filesystem(&hppfs_type));
 789 }
 790
 791 static void __exit exit_hppfs(void)
 792 {
 793         unregister_filesystem(&hppfs_type);
 794 }
 795
 796 module_init(init_hppfs)
 797 module_exit(exit_hppfs)
 798 MODULE_LICENSE("GPL");
 799
 800 /*
 801  * Overrides for Emacs so that we follow Linus's tabbing style.
 802  * Emacs will notice this stuff at the end of the file and automatically
 803  * adjust the settings for this buffer only.  This must remain at the end
 804  * of the file.
 805  * ---------------------------------------------------------------------------
 806  * Local variables:
 807  * c-file-style: "linux"
 808  * End:
 809  */