1 /* 2 * net/sunrpc/rpc_pipe.c 3 * 4 * Userland/kernel interface for rpcauth_gss. 5 * Code shamelessly plagiarized from fs/nfsd/nfsctl.c 6 * and fs/sysfs/inode.c 7 * 8 * Copyright (c) 2002, Trond Myklebust <trond.myklebust@fys.uio.no> 9 * 10 */ 11 #include <linux/config.h> 12 #include <linux/module.h> 13 #include <linux/slab.h> 14 #include <linux/string.h> 15 #include <linux/pagemap.h> 16 #include <linux/mount.h> 17 #include <linux/namei.h> 18 #include <linux/dnotify.h> 19 #include <linux/kernel.h> 20 21 #include <asm/ioctls.h> 22 #include <linux/fs.h> 23 #include <linux/poll.h> 24 #include <linux/wait.h> 25 #include <linux/seq_file.h> 26 27 #include <linux/sunrpc/clnt.h> 28 #include <linux/workqueue.h> 29 #include <linux/sunrpc/rpc_pipe_fs.h> 30 31 static struct vfsmount *rpc_mount __read_mostly; 32 static int rpc_mount_count; 33 34 static struct file_system_type rpc_pipe_fs_type; 35 36 37 static kmem_cache_t *rpc_inode_cachep __read_mostly; 38 39 #define RPC_UPCALL_TIMEOUT (30*HZ) 40 41 static void 42 __rpc_purge_list(struct rpc_inode *rpci, struct list_head *head, int err) 43 { 44 struct rpc_pipe_msg *msg; 45 void (*destroy_msg)(struct rpc_pipe_msg *); 46 47 destroy_msg = rpci->ops->destroy_msg; 48 while (!list_empty(head)) { 49 msg = list_entry(head->next, struct rpc_pipe_msg, list); 50 list_del_init(&msg->list); 51 msg->errno = err; 52 destroy_msg(msg); 53 } 54 } 55 56 static void 57 __rpc_purge_upcall(struct inode *inode, int err) 58 { 59 struct rpc_inode *rpci = RPC_I(inode); 60 61 __rpc_purge_list(rpci, &rpci->pipe, err); 62 rpci->pipelen = 0; 63 wake_up(&rpci->waitq); 64 } 65 66 static void 67 rpc_timeout_upcall_queue(void *data) 68 { 69 struct rpc_inode *rpci = (struct rpc_inode *)data; 70 struct inode *inode = &rpci->vfs_inode; 71 72 mutex_lock(&inode->i_mutex); 73 if (rpci->ops == NULL) 74 goto out; 75 if (rpci->nreaders == 0 && !list_empty(&rpci->pipe)) 76 __rpc_purge_upcall(inode, -ETIMEDOUT); 77 out: 78 mutex_unlock(&inode->i_mutex); 79 } 80 81 int 82 rpc_queue_upcall(struct inode *inode, struct rpc_pipe_msg *msg) 83 { 84 struct rpc_inode *rpci = RPC_I(inode); 85 int res = -EPIPE; 86 87 mutex_lock(&inode->i_mutex); 88 if (rpci->ops == NULL) 89 goto out; 90 if (rpci->nreaders) { 91 list_add_tail(&msg->list, &rpci->pipe); 92 rpci->pipelen += msg->len; 93 res = 0; 94 } else if (rpci->flags & RPC_PIPE_WAIT_FOR_OPEN) { 95 if (list_empty(&rpci->pipe)) 96 schedule_delayed_work(&rpci->queue_timeout, 97 RPC_UPCALL_TIMEOUT); 98 list_add_tail(&msg->list, &rpci->pipe); 99 rpci->pipelen += msg->len; 100 res = 0; 101 } 102 out: 103 mutex_unlock(&inode->i_mutex); 104 wake_up(&rpci->waitq); 105 return res; 106 } 107 108 static inline void 109 rpc_inode_setowner(struct inode *inode, void *private) 110 { 111 RPC_I(inode)->private = private; 112 } 113 114 static void 115 rpc_close_pipes(struct inode *inode) 116 { 117 struct rpc_inode *rpci = RPC_I(inode); 118 119 mutex_lock(&inode->i_mutex); 120 if (rpci->ops != NULL) { 121 rpci->nreaders = 0; 122 __rpc_purge_list(rpci, &rpci->in_upcall, -EPIPE); 123 __rpc_purge_upcall(inode, -EPIPE); 124 rpci->nwriters = 0; 125 if (rpci->ops->release_pipe) 126 rpci->ops->release_pipe(inode); 127 rpci->ops = NULL; 128 } 129 rpc_inode_setowner(inode, NULL); 130 mutex_unlock(&inode->i_mutex); 131 cancel_delayed_work(&rpci->queue_timeout); 132 flush_scheduled_work(); 133 } 134 135 static struct inode * 136 rpc_alloc_inode(struct super_block *sb) 137 { 138 struct rpc_inode *rpci; 139 rpci = (struct rpc_inode *)kmem_cache_alloc(rpc_inode_cachep, SLAB_KERNEL); 140 if (!rpci) 141 return NULL; 142 return &rpci->vfs_inode; 143 } 144 145 static void 146 rpc_destroy_inode(struct inode *inode) 147 { 148 kmem_cache_free(rpc_inode_cachep, RPC_I(inode)); 149 } 150 151 static int 152 rpc_pipe_open(struct inode *inode, struct file *filp) 153 { 154 struct rpc_inode *rpci = RPC_I(inode); 155 int res = -ENXIO; 156 157 mutex_lock(&inode->i_mutex); 158 if (rpci->ops != NULL) { 159 if (filp->f_mode & FMODE_READ) 160 rpci->nreaders ++; 161 if (filp->f_mode & FMODE_WRITE) 162 rpci->nwriters ++; 163 res = 0; 164 } 165 mutex_unlock(&inode->i_mutex); 166 return res; 167 } 168 169 static int 170 rpc_pipe_release(struct inode *inode, struct file *filp) 171 { 172 struct rpc_inode *rpci = RPC_I(inode); 173 struct rpc_pipe_msg *msg; 174 175 mutex_lock(&inode->i_mutex); 176 if (rpci->ops == NULL) 177 goto out; 178 msg = (struct rpc_pipe_msg *)filp->private_data; 179 if (msg != NULL) { 180 msg->errno = -EAGAIN; 181 list_del_init(&msg->list); 182 rpci->ops->destroy_msg(msg); 183 } 184 if (filp->f_mode & FMODE_WRITE) 185 rpci->nwriters --; 186 if (filp->f_mode & FMODE_READ) 187 rpci->nreaders --; 188 if (!rpci->nreaders) 189 __rpc_purge_upcall(inode, -EAGAIN); 190 if (rpci->ops->release_pipe) 191 rpci->ops->release_pipe(inode); 192 out: 193 mutex_unlock(&inode->i_mutex); 194 return 0; 195 } 196 197 static ssize_t 198 rpc_pipe_read(struct file *filp, char __user *buf, size_t len, loff_t *offset) 199 { 200 struct inode *inode = filp->f_dentry->d_inode; 201 struct rpc_inode *rpci = RPC_I(inode); 202 struct rpc_pipe_msg *msg; 203 int res = 0; 204 205 mutex_lock(&inode->i_mutex); 206 if (rpci->ops == NULL) { 207 res = -EPIPE; 208 goto out_unlock; 209 } 210 msg = filp->private_data; 211 if (msg == NULL) { 212 if (!list_empty(&rpci->pipe)) { 213 msg = list_entry(rpci->pipe.next, 214 struct rpc_pipe_msg, 215 list); 216 list_move(&msg->list, &rpci->in_upcall); 217 rpci->pipelen -= msg->len; 218 filp->private_data = msg; 219 msg->copied = 0; 220 } 221 if (msg == NULL) 222 goto out_unlock; 223 } 224 /* NOTE: it is up to the callback to update msg->copied */ 225 res = rpci->ops->upcall(filp, msg, buf, len); 226 if (res < 0 || msg->len == msg->copied) { 227 filp->private_data = NULL; 228 list_del_init(&msg->list); 229 rpci->ops->destroy_msg(msg); 230 } 231 out_unlock: 232 mutex_unlock(&inode->i_mutex); 233 return res; 234 } 235 236 static ssize_t 237 rpc_pipe_write(struct file *filp, const char __user *buf, size_t len, loff_t *offset) 238 { 239 struct inode *inode = filp->f_dentry->d_inode; 240 struct rpc_inode *rpci = RPC_I(inode); 241 int res; 242 243 mutex_lock(&inode->i_mutex); 244 res = -EPIPE; 245 if (rpci->ops != NULL) 246 res = rpci->ops->downcall(filp, buf, len); 247 mutex_unlock(&inode->i_mutex); 248 return res; 249 } 250 251 static unsigned int 252 rpc_pipe_poll(struct file *filp, struct poll_table_struct *wait) 253 { 254 struct rpc_inode *rpci; 255 unsigned int mask = 0; 256 257 rpci = RPC_I(filp->f_dentry->d_inode); 258 poll_wait(filp, &rpci->waitq, wait); 259 260 mask = POLLOUT | POLLWRNORM; 261 if (rpci->ops == NULL) 262 mask |= POLLERR | POLLHUP; 263 if (!list_empty(&rpci->pipe)) 264 mask |= POLLIN | POLLRDNORM; 265 return mask; 266 } 267 268 static int 269 rpc_pipe_ioctl(struct inode *ino, struct file *filp, 270 unsigned int cmd, unsigned long arg) 271 { 272 struct rpc_inode *rpci = RPC_I(filp->f_dentry->d_inode); 273 int len; 274 275 switch (cmd) { 276 case FIONREAD: 277 if (rpci->ops == NULL) 278 return -EPIPE; 279 len = rpci->pipelen; 280 if (filp->private_data) { 281 struct rpc_pipe_msg *msg; 282 msg = (struct rpc_pipe_msg *)filp->private_data; 283 len += msg->len - msg->copied; 284 } 285 return put_user(len, (int __user *)arg); 286 default: 287 return -EINVAL; 288 } 289 } 290 291 static struct file_operations rpc_pipe_fops = { 292 .owner = THIS_MODULE, 293 .llseek = no_llseek, 294 .read = rpc_pipe_read, 295 .write = rpc_pipe_write, 296 .poll = rpc_pipe_poll, 297 .ioctl = rpc_pipe_ioctl, 298 .open = rpc_pipe_open, 299 .release = rpc_pipe_release, 300 }; 301 302 static int 303 rpc_show_info(struct seq_file *m, void *v) 304 { 305 struct rpc_clnt *clnt = m->private; 306 307 seq_printf(m, "RPC server: %s\n", clnt->cl_server); 308 seq_printf(m, "service: %s (%d) version %d\n", clnt->cl_protname, 309 clnt->cl_prog, clnt->cl_vers); 310 seq_printf(m, "address: %u.%u.%u.%u\n", 311 NIPQUAD(clnt->cl_xprt->addr.sin_addr.s_addr)); 312 seq_printf(m, "protocol: %s\n", 313 clnt->cl_xprt->prot == IPPROTO_UDP ? "udp" : "tcp"); 314 return 0; 315 } 316 317 static int 318 rpc_info_open(struct inode *inode, struct file *file) 319 { 320 struct rpc_clnt *clnt; 321 int ret = single_open(file, rpc_show_info, NULL); 322 323 if (!ret) { 324 struct seq_file *m = file->private_data; 325 mutex_lock(&inode->i_mutex); 326 clnt = RPC_I(inode)->private; 327 if (clnt) { 328 atomic_inc(&clnt->cl_users); 329 m->private = clnt; 330 } else { 331 single_release(inode, file); 332 ret = -EINVAL; 333 } 334 mutex_unlock(&inode->i_mutex); 335 } 336 return ret; 337 } 338 339 static int 340 rpc_info_release(struct inode *inode, struct file *file) 341 { 342 struct seq_file *m = file->private_data; 343 struct rpc_clnt *clnt = (struct rpc_clnt *)m->private; 344 345 if (clnt) 346 rpc_release_client(clnt); 347 return single_release(inode, file); 348 } 349 350 static struct file_operations rpc_info_operations = { 351 .owner = THIS_MODULE, 352 .open = rpc_info_open, 353 .read = seq_read, 354 .llseek = seq_lseek, 355 .release = rpc_info_release, 356 }; 357 358 359 /* 360 * We have a single directory with 1 node in it. 361 */ 362 enum { 363 RPCAUTH_Root = 1, 364 RPCAUTH_lockd, 365 RPCAUTH_mount, 366 RPCAUTH_nfs, 367 RPCAUTH_portmap, 368 RPCAUTH_statd, 369 RPCAUTH_RootEOF 370 }; 371 372 /* 373 * Description of fs contents. 374 */ 375 struct rpc_filelist { 376 char *name; 377 struct file_operations *i_fop; 378 int mode; 379 }; 380 381 static struct rpc_filelist files[] = { 382 [RPCAUTH_lockd] = { 383 .name = "lockd", 384 .mode = S_IFDIR | S_IRUGO | S_IXUGO, 385 }, 386 [RPCAUTH_mount] = { 387 .name = "mount", 388 .mode = S_IFDIR | S_IRUGO | S_IXUGO, 389 }, 390 [RPCAUTH_nfs] = { 391 .name = "nfs", 392 .mode = S_IFDIR | S_IRUGO | S_IXUGO, 393 }, 394 [RPCAUTH_portmap] = { 395 .name = "portmap", 396 .mode = S_IFDIR | S_IRUGO | S_IXUGO, 397 }, 398 [RPCAUTH_statd] = { 399 .name = "statd", 400 .mode = S_IFDIR | S_IRUGO | S_IXUGO, 401 }, 402 }; 403 404 enum { 405 RPCAUTH_info = 2, 406 RPCAUTH_EOF 407 }; 408 409 static struct rpc_filelist authfiles[] = { 410 [RPCAUTH_info] = { 411 .name = "info", 412 .i_fop = &rpc_info_operations, 413 .mode = S_IFREG | S_IRUSR, 414 }, 415 }; 416 417 static int 418 rpc_get_mount(void) 419 { 420 return simple_pin_fs("rpc_pipefs", &rpc_mount, &rpc_mount_count); 421 } 422 423 static void 424 rpc_put_mount(void) 425 { 426 simple_release_fs(&rpc_mount, &rpc_mount_count); 427 } 428 429 static int 430 rpc_lookup_parent(char *path, struct nameidata *nd) 431 { 432 if (path[0] == '\0') 433 return -ENOENT; 434 if (rpc_get_mount()) { 435 printk(KERN_WARNING "%s: %s failed to mount " 436 "pseudofilesystem \n", __FILE__, __FUNCTION__); 437 return -ENODEV; 438 } 439 nd->mnt = mntget(rpc_mount); 440 nd->dentry = dget(rpc_mount->mnt_root); 441 nd->last_type = LAST_ROOT; 442 nd->flags = LOOKUP_PARENT; 443 nd->depth = 0; 444 445 if (path_walk(path, nd)) { 446 printk(KERN_WARNING "%s: %s failed to find path %s\n", 447 __FILE__, __FUNCTION__, path); 448 rpc_put_mount(); 449 return -ENOENT; 450 } 451 return 0; 452 } 453 454 static void 455 rpc_release_path(struct nameidata *nd) 456 { 457 path_release(nd); 458 rpc_put_mount(); 459 } 460 461 static struct inode * 462 rpc_get_inode(struct super_block *sb, int mode) 463 { 464 struct inode *inode = new_inode(sb); 465 if (!inode) 466 return NULL; 467 inode->i_mode = mode; 468 inode->i_uid = inode->i_gid = 0; 469 inode->i_blksize = PAGE_CACHE_SIZE; 470 inode->i_blocks = 0; 471 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; 472 switch(mode & S_IFMT) { 473 case S_IFDIR: 474 inode->i_fop = &simple_dir_operations; 475 inode->i_op = &simple_dir_inode_operations; 476 inode->i_nlink++; 477 default: 478 break; 479 } 480 return inode; 481 } 482 483 /* 484 * FIXME: This probably has races. 485 */ 486 static void 487 rpc_depopulate(struct dentry *parent) 488 { 489 struct inode *dir = parent->d_inode; 490 struct list_head *pos, *next; 491 struct dentry *dentry, *dvec[10]; 492 int n = 0; 493 494 mutex_lock(&dir->i_mutex); 495 repeat: 496 spin_lock(&dcache_lock); 497 list_for_each_safe(pos, next, &parent->d_subdirs) { 498 dentry = list_entry(pos, struct dentry, d_u.d_child); 499 spin_lock(&dentry->d_lock); 500 if (!d_unhashed(dentry)) { 501 dget_locked(dentry); 502 __d_drop(dentry); 503 spin_unlock(&dentry->d_lock); 504 dvec[n++] = dentry; 505 if (n == ARRAY_SIZE(dvec)) 506 break; 507 } else 508 spin_unlock(&dentry->d_lock); 509 } 510 spin_unlock(&dcache_lock); 511 if (n) { 512 do { 513 dentry = dvec[--n]; 514 if (dentry->d_inode) { 515 rpc_close_pipes(dentry->d_inode); 516 simple_unlink(dir, dentry); 517 } 518 dput(dentry); 519 } while (n); 520 goto repeat; 521 } 522 mutex_unlock(&dir->i_mutex); 523 } 524 525 static int 526 rpc_populate(struct dentry *parent, 527 struct rpc_filelist *files, 528 int start, int eof) 529 { 530 struct inode *inode, *dir = parent->d_inode; 531 void *private = RPC_I(dir)->private; 532 struct dentry *dentry; 533 int mode, i; 534 535 mutex_lock(&dir->i_mutex); 536 for (i = start; i < eof; i++) { 537 dentry = d_alloc_name(parent, files[i].name); 538 if (!dentry) 539 goto out_bad; 540 mode = files[i].mode; 541 inode = rpc_get_inode(dir->i_sb, mode); 542 if (!inode) { 543 dput(dentry); 544 goto out_bad; 545 } 546 inode->i_ino = i; 547 if (files[i].i_fop) 548 inode->i_fop = files[i].i_fop; 549 if (private) 550 rpc_inode_setowner(inode, private); 551 if (S_ISDIR(mode)) 552 dir->i_nlink++; 553 d_add(dentry, inode); 554 } 555 mutex_unlock(&dir->i_mutex); 556 return 0; 557 out_bad: 558 mutex_unlock(&dir->i_mutex); 559 printk(KERN_WARNING "%s: %s failed to populate directory %s\n", 560 __FILE__, __FUNCTION__, parent->d_name.name); 561 return -ENOMEM; 562 } 563 564 static int 565 __rpc_mkdir(struct inode *dir, struct dentry *dentry) 566 { 567 struct inode *inode; 568 569 inode = rpc_get_inode(dir->i_sb, S_IFDIR | S_IRUSR | S_IXUSR); 570 if (!inode) 571 goto out_err; 572 inode->i_ino = iunique(dir->i_sb, 100); 573 d_instantiate(dentry, inode); 574 dir->i_nlink++; 575 inode_dir_notify(dir, DN_CREATE); 576 rpc_get_mount(); 577 return 0; 578 out_err: 579 printk(KERN_WARNING "%s: %s failed to allocate inode for dentry %s\n", 580 __FILE__, __FUNCTION__, dentry->d_name.name); 581 return -ENOMEM; 582 } 583 584 static int 585 __rpc_rmdir(struct inode *dir, struct dentry *dentry) 586 { 587 int error; 588 589 shrink_dcache_parent(dentry); 590 if (dentry->d_inode) 591 rpc_close_pipes(dentry->d_inode); 592 if ((error = simple_rmdir(dir, dentry)) != 0) 593 return error; 594 if (!error) { 595 inode_dir_notify(dir, DN_DELETE); 596 d_drop(dentry); 597 rpc_put_mount(); 598 } 599 return 0; 600 } 601 602 static struct dentry * 603 rpc_lookup_negative(char *path, struct nameidata *nd) 604 { 605 struct dentry *dentry; 606 struct inode *dir; 607 int error; 608 609 if ((error = rpc_lookup_parent(path, nd)) != 0) 610 return ERR_PTR(error); 611 dir = nd->dentry->d_inode; 612 mutex_lock(&dir->i_mutex); 613 dentry = lookup_hash(nd); 614 if (IS_ERR(dentry)) 615 goto out_err; 616 if (dentry->d_inode) { 617 dput(dentry); 618 dentry = ERR_PTR(-EEXIST); 619 goto out_err; 620 } 621 return dentry; 622 out_err: 623 mutex_unlock(&dir->i_mutex); 624 rpc_release_path(nd); 625 return dentry; 626 } 627 628 629 struct dentry * 630 rpc_mkdir(char *path, struct rpc_clnt *rpc_client) 631 { 632 struct nameidata nd; 633 struct dentry *dentry; 634 struct inode *dir; 635 int error; 636 637 dentry = rpc_lookup_negative(path, &nd); 638 if (IS_ERR(dentry)) 639 return dentry; 640 dir = nd.dentry->d_inode; 641 if ((error = __rpc_mkdir(dir, dentry)) != 0) 642 goto err_dput; 643 RPC_I(dentry->d_inode)->private = rpc_client; 644 error = rpc_populate(dentry, authfiles, 645 RPCAUTH_info, RPCAUTH_EOF); 646 if (error) 647 goto err_depopulate; 648 out: 649 mutex_unlock(&dir->i_mutex); 650 rpc_release_path(&nd); 651 return dentry; 652 err_depopulate: 653 rpc_depopulate(dentry); 654 __rpc_rmdir(dir, dentry); 655 err_dput: 656 dput(dentry); 657 printk(KERN_WARNING "%s: %s() failed to create directory %s (errno = %d)\n", 658 __FILE__, __FUNCTION__, path, error); 659 dentry = ERR_PTR(error); 660 goto out; 661 } 662 663 int 664 rpc_rmdir(char *path) 665 { 666 struct nameidata nd; 667 struct dentry *dentry; 668 struct inode *dir; 669 int error; 670 671 if ((error = rpc_lookup_parent(path, &nd)) != 0) 672 return error; 673 dir = nd.dentry->d_inode; 674 mutex_lock(&dir->i_mutex); 675 dentry = lookup_hash(&nd); 676 if (IS_ERR(dentry)) { 677 error = PTR_ERR(dentry); 678 goto out_release; 679 } 680 rpc_depopulate(dentry); 681 error = __rpc_rmdir(dir, dentry); 682 dput(dentry); 683 out_release: 684 mutex_unlock(&dir->i_mutex); 685 rpc_release_path(&nd); 686 return error; 687 } 688 689 struct dentry * 690 rpc_mkpipe(char *path, void *private, struct rpc_pipe_ops *ops, int flags) 691 { 692 struct nameidata nd; 693 struct dentry *dentry; 694 struct inode *dir, *inode; 695 struct rpc_inode *rpci; 696 697 dentry = rpc_lookup_negative(path, &nd); 698 if (IS_ERR(dentry)) 699 return dentry; 700 dir = nd.dentry->d_inode; 701 inode = rpc_get_inode(dir->i_sb, S_IFSOCK | S_IRUSR | S_IWUSR); 702 if (!inode) 703 goto err_dput; 704 inode->i_ino = iunique(dir->i_sb, 100); 705 inode->i_fop = &rpc_pipe_fops; 706 d_instantiate(dentry, inode); 707 rpci = RPC_I(inode); 708 rpci->private = private; 709 rpci->flags = flags; 710 rpci->ops = ops; 711 inode_dir_notify(dir, DN_CREATE); 712 out: 713 mutex_unlock(&dir->i_mutex); 714 rpc_release_path(&nd); 715 return dentry; 716 err_dput: 717 dput(dentry); 718 dentry = ERR_PTR(-ENOMEM); 719 printk(KERN_WARNING "%s: %s() failed to create pipe %s (errno = %d)\n", 720 __FILE__, __FUNCTION__, path, -ENOMEM); 721 goto out; 722 } 723 724 int 725 rpc_unlink(char *path) 726 { 727 struct nameidata nd; 728 struct dentry *dentry; 729 struct inode *dir; 730 int error; 731 732 if ((error = rpc_lookup_parent(path, &nd)) != 0) 733 return error; 734 dir = nd.dentry->d_inode; 735 mutex_lock(&dir->i_mutex); 736 dentry = lookup_hash(&nd); 737 if (IS_ERR(dentry)) { 738 error = PTR_ERR(dentry); 739 goto out_release; 740 } 741 d_drop(dentry); 742 if (dentry->d_inode) { 743 rpc_close_pipes(dentry->d_inode); 744 error = simple_unlink(dir, dentry); 745 } 746 dput(dentry); 747 inode_dir_notify(dir, DN_DELETE); 748 out_release: 749 mutex_unlock(&dir->i_mutex); 750 rpc_release_path(&nd); 751 return error; 752 } 753 754 /* 755 * populate the filesystem 756 */ 757 static struct super_operations s_ops = { 758 .alloc_inode = rpc_alloc_inode, 759 .destroy_inode = rpc_destroy_inode, 760 .statfs = simple_statfs, 761 }; 762 763 #define RPCAUTH_GSSMAGIC 0x67596969 764 765 static int 766 rpc_fill_super(struct super_block *sb, void *data, int silent) 767 { 768 struct inode *inode; 769 struct dentry *root; 770 771 sb->s_blocksize = PAGE_CACHE_SIZE; 772 sb->s_blocksize_bits = PAGE_CACHE_SHIFT; 773 sb->s_magic = RPCAUTH_GSSMAGIC; 774 sb->s_op = &s_ops; 775 sb->s_time_gran = 1; 776 777 inode = rpc_get_inode(sb, S_IFDIR | 0755); 778 if (!inode) 779 return -ENOMEM; 780 root = d_alloc_root(inode); 781 if (!root) { 782 iput(inode); 783 return -ENOMEM; 784 } 785 if (rpc_populate(root, files, RPCAUTH_Root + 1, RPCAUTH_RootEOF)) 786 goto out; 787 sb->s_root = root; 788 return 0; 789 out: 790 d_genocide(root); 791 dput(root); 792 return -ENOMEM; 793 } 794 795 static struct super_block * 796 rpc_get_sb(struct file_system_type *fs_type, 797 int flags, const char *dev_name, void *data) 798 { 799 return get_sb_single(fs_type, flags, data, rpc_fill_super); 800 } 801 802 static struct file_system_type rpc_pipe_fs_type = { 803 .owner = THIS_MODULE, 804 .name = "rpc_pipefs", 805 .get_sb = rpc_get_sb, 806 .kill_sb = kill_litter_super, 807 }; 808 809 static void 810 init_once(void * foo, kmem_cache_t * cachep, unsigned long flags) 811 { 812 struct rpc_inode *rpci = (struct rpc_inode *) foo; 813 814 if ((flags & (SLAB_CTOR_VERIFY|SLAB_CTOR_CONSTRUCTOR)) == 815 SLAB_CTOR_CONSTRUCTOR) { 816 inode_init_once(&rpci->vfs_inode); 817 rpci->private = NULL; 818 rpci->nreaders = 0; 819 rpci->nwriters = 0; 820 INIT_LIST_HEAD(&rpci->in_upcall); 821 INIT_LIST_HEAD(&rpci->pipe); 822 rpci->pipelen = 0; 823 init_waitqueue_head(&rpci->waitq); 824 INIT_WORK(&rpci->queue_timeout, rpc_timeout_upcall_queue, rpci); 825 rpci->ops = NULL; 826 } 827 } 828 829 int register_rpc_pipefs(void) 830 { 831 rpc_inode_cachep = kmem_cache_create("rpc_inode_cache", 832 sizeof(struct rpc_inode), 833 0, SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT, 834 init_once, NULL); 835 if (!rpc_inode_cachep) 836 return -ENOMEM; 837 register_filesystem(&rpc_pipe_fs_type); 838 return 0; 839 } 840 841 void unregister_rpc_pipefs(void) 842 { 843 if (kmem_cache_destroy(rpc_inode_cachep)) 844 printk(KERN_WARNING "RPC: unable to free inode cache\n"); 845 unregister_filesystem(&rpc_pipe_fs_type); 846 } 847