1// SPDX-License-Identifier: GPL-2.0-only 2/* 3 * net/sunrpc/rpc_pipe.c 4 * 5 * Userland/kernel interface for rpcauth_gss. 6 * Code shamelessly plagiarized from fs/nfsd/nfsctl.c 7 * and fs/sysfs/inode.c 8 * 9 * Copyright (c) 2002, Trond Myklebust <trond.myklebust@fys.uio.no> 10 * 11 */ 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/fs_context.h> 18#include <linux/namei.h> 19#include <linux/fsnotify.h> 20#include <linux/kernel.h> 21#include <linux/rcupdate.h> 22#include <linux/utsname.h> 23 24#include <asm/ioctls.h> 25#include <linux/poll.h> 26#include <linux/wait.h> 27#include <linux/seq_file.h> 28 29#include <linux/sunrpc/clnt.h> 30#include <linux/workqueue.h> 31#include <linux/sunrpc/rpc_pipe_fs.h> 32#include <linux/sunrpc/cache.h> 33#include <linux/nsproxy.h> 34#include <linux/notifier.h> 35 36#include "netns.h" 37#include "sunrpc.h" 38 39#define RPCDBG_FACILITY RPCDBG_DEBUG 40 41#define NET_NAME(net) ((net == &init_net) ? " (init_net)" : "") 42 43static struct file_system_type rpc_pipe_fs_type; 44static const struct rpc_pipe_ops gssd_dummy_pipe_ops; 45 46static struct kmem_cache *rpc_inode_cachep __read_mostly; 47 48#define RPC_UPCALL_TIMEOUT (30*HZ) 49 50static BLOCKING_NOTIFIER_HEAD(rpc_pipefs_notifier_list); 51 52int rpc_pipefs_notifier_register(struct notifier_block *nb) 53{ 54 return blocking_notifier_chain_register(&rpc_pipefs_notifier_list, nb); 55} 56EXPORT_SYMBOL_GPL(rpc_pipefs_notifier_register); 57 58void rpc_pipefs_notifier_unregister(struct notifier_block *nb) 59{ 60 blocking_notifier_chain_unregister(&rpc_pipefs_notifier_list, nb); 61} 62EXPORT_SYMBOL_GPL(rpc_pipefs_notifier_unregister); 63 64static void rpc_purge_list(wait_queue_head_t *waitq, struct list_head *head, 65 void (*destroy_msg)(struct rpc_pipe_msg *), int err) 66{ 67 struct rpc_pipe_msg *msg; 68 69 if (list_empty(head)) 70 return; 71 do { 72 msg = list_entry(head->next, struct rpc_pipe_msg, list); 73 list_del_init(&msg->list); 74 msg->errno = err; 75 destroy_msg(msg); 76 } while (!list_empty(head)); 77 78 if (waitq) 79 wake_up(waitq); 80} 81 82static void 83rpc_timeout_upcall_queue(struct work_struct *work) 84{ 85 LIST_HEAD(free_list); 86 struct rpc_pipe *pipe = 87 container_of(work, struct rpc_pipe, queue_timeout.work); 88 void (*destroy_msg)(struct rpc_pipe_msg *); 89 struct dentry *dentry; 90 91 spin_lock(&pipe->lock); 92 destroy_msg = pipe->ops->destroy_msg; 93 if (pipe->nreaders == 0) { 94 list_splice_init(&pipe->pipe, &free_list); 95 pipe->pipelen = 0; 96 } 97 dentry = dget(pipe->dentry); 98 spin_unlock(&pipe->lock); 99 rpc_purge_list(dentry ? &RPC_I(d_inode(dentry))->waitq : NULL, 100 &free_list, destroy_msg, -ETIMEDOUT); 101 dput(dentry); 102} 103 104ssize_t rpc_pipe_generic_upcall(struct file *filp, struct rpc_pipe_msg *msg, 105 char __user *dst, size_t buflen) 106{ 107 char *data = (char *)msg->data + msg->copied; 108 size_t mlen = min(msg->len - msg->copied, buflen); 109 unsigned long left; 110 111 left = copy_to_user(dst, data, mlen); 112 if (left == mlen) { 113 msg->errno = -EFAULT; 114 return -EFAULT; 115 } 116 117 mlen -= left; 118 msg->copied += mlen; 119 msg->errno = 0; 120 return mlen; 121} 122EXPORT_SYMBOL_GPL(rpc_pipe_generic_upcall); 123 124/** 125 * rpc_queue_upcall - queue an upcall message to userspace 126 * @pipe: upcall pipe on which to queue given message 127 * @msg: message to queue 128 * 129 * Call with an @inode created by rpc_mkpipe() to queue an upcall. 130 * A userspace process may then later read the upcall by performing a 131 * read on an open file for this inode. It is up to the caller to 132 * initialize the fields of @msg (other than @msg->list) appropriately. 133 */ 134int 135rpc_queue_upcall(struct rpc_pipe *pipe, struct rpc_pipe_msg *msg) 136{ 137 int res = -EPIPE; 138 struct dentry *dentry; 139 140 spin_lock(&pipe->lock); 141 if (pipe->nreaders) { 142 list_add_tail(&msg->list, &pipe->pipe); 143 pipe->pipelen += msg->len; 144 res = 0; 145 } else if (pipe->flags & RPC_PIPE_WAIT_FOR_OPEN) { 146 if (list_empty(&pipe->pipe)) 147 queue_delayed_work(rpciod_workqueue, 148 &pipe->queue_timeout, 149 RPC_UPCALL_TIMEOUT); 150 list_add_tail(&msg->list, &pipe->pipe); 151 pipe->pipelen += msg->len; 152 res = 0; 153 } 154 dentry = dget(pipe->dentry); 155 spin_unlock(&pipe->lock); 156 if (dentry) { 157 wake_up(&RPC_I(d_inode(dentry))->waitq); 158 dput(dentry); 159 } 160 return res; 161} 162EXPORT_SYMBOL_GPL(rpc_queue_upcall); 163 164static inline void 165rpc_inode_setowner(struct inode *inode, void *private) 166{ 167 RPC_I(inode)->private = private; 168} 169 170static void 171rpc_close_pipes(struct inode *inode) 172{ 173 struct rpc_pipe *pipe = RPC_I(inode)->pipe; 174 int need_release; 175 LIST_HEAD(free_list); 176 177 inode_lock(inode); 178 spin_lock(&pipe->lock); 179 need_release = pipe->nreaders != 0 || pipe->nwriters != 0; 180 pipe->nreaders = 0; 181 list_splice_init(&pipe->in_upcall, &free_list); 182 list_splice_init(&pipe->pipe, &free_list); 183 pipe->pipelen = 0; 184 pipe->dentry = NULL; 185 spin_unlock(&pipe->lock); 186 rpc_purge_list(&RPC_I(inode)->waitq, &free_list, pipe->ops->destroy_msg, -EPIPE); 187 pipe->nwriters = 0; 188 if (need_release && pipe->ops->release_pipe) 189 pipe->ops->release_pipe(inode); 190 cancel_delayed_work_sync(&pipe->queue_timeout); 191 rpc_inode_setowner(inode, NULL); 192 RPC_I(inode)->pipe = NULL; 193 inode_unlock(inode); 194} 195 196static struct inode * 197rpc_alloc_inode(struct super_block *sb) 198{ 199 struct rpc_inode *rpci; 200 rpci = alloc_inode_sb(sb, rpc_inode_cachep, GFP_KERNEL); 201 if (!rpci) 202 return NULL; 203 return &rpci->vfs_inode; 204} 205 206static void 207rpc_free_inode(struct inode *inode) 208{ 209 kmem_cache_free(rpc_inode_cachep, RPC_I(inode)); 210} 211 212static int 213rpc_pipe_open(struct inode *inode, struct file *filp) 214{ 215 struct rpc_pipe *pipe; 216 int first_open; 217 int res = -ENXIO; 218 219 inode_lock(inode); 220 pipe = RPC_I(inode)->pipe; 221 if (pipe == NULL) 222 goto out; 223 first_open = pipe->nreaders == 0 && pipe->nwriters == 0; 224 if (first_open && pipe->ops->open_pipe) { 225 res = pipe->ops->open_pipe(inode); 226 if (res) 227 goto out; 228 } 229 if (filp->f_mode & FMODE_READ) 230 pipe->nreaders++; 231 if (filp->f_mode & FMODE_WRITE) 232 pipe->nwriters++; 233 res = 0; 234out: 235 inode_unlock(inode); 236 return res; 237} 238 239static int 240rpc_pipe_release(struct inode *inode, struct file *filp) 241{ 242 struct rpc_pipe *pipe; 243 struct rpc_pipe_msg *msg; 244 int last_close; 245 246 inode_lock(inode); 247 pipe = RPC_I(inode)->pipe; 248 if (pipe == NULL) 249 goto out; 250 msg = filp->private_data; 251 if (msg != NULL) { 252 spin_lock(&pipe->lock); 253 msg->errno = -EAGAIN; 254 list_del_init(&msg->list); 255 spin_unlock(&pipe->lock); 256 pipe->ops->destroy_msg(msg); 257 } 258 if (filp->f_mode & FMODE_WRITE) 259 pipe->nwriters --; 260 if (filp->f_mode & FMODE_READ) { 261 pipe->nreaders --; 262 if (pipe->nreaders == 0) { 263 LIST_HEAD(free_list); 264 spin_lock(&pipe->lock); 265 list_splice_init(&pipe->pipe, &free_list); 266 pipe->pipelen = 0; 267 spin_unlock(&pipe->lock); 268 rpc_purge_list(&RPC_I(inode)->waitq, &free_list, 269 pipe->ops->destroy_msg, -EAGAIN); 270 } 271 } 272 last_close = pipe->nwriters == 0 && pipe->nreaders == 0; 273 if (last_close && pipe->ops->release_pipe) 274 pipe->ops->release_pipe(inode); 275out: 276 inode_unlock(inode); 277 return 0; 278} 279 280static ssize_t 281rpc_pipe_read(struct file *filp, char __user *buf, size_t len, loff_t *offset) 282{ 283 struct inode *inode = file_inode(filp); 284 struct rpc_pipe *pipe; 285 struct rpc_pipe_msg *msg; 286 int res = 0; 287 288 inode_lock(inode); 289 pipe = RPC_I(inode)->pipe; 290 if (pipe == NULL) { 291 res = -EPIPE; 292 goto out_unlock; 293 } 294 msg = filp->private_data; 295 if (msg == NULL) { 296 spin_lock(&pipe->lock); 297 if (!list_empty(&pipe->pipe)) { 298 msg = list_entry(pipe->pipe.next, 299 struct rpc_pipe_msg, 300 list); 301 list_move(&msg->list, &pipe->in_upcall); 302 pipe->pipelen -= msg->len; 303 filp->private_data = msg; 304 msg->copied = 0; 305 } 306 spin_unlock(&pipe->lock); 307 if (msg == NULL) 308 goto out_unlock; 309 } 310 /* NOTE: it is up to the callback to update msg->copied */ 311 res = pipe->ops->upcall(filp, msg, buf, len); 312 if (res < 0 || msg->len == msg->copied) { 313 filp->private_data = NULL; 314 spin_lock(&pipe->lock); 315 list_del_init(&msg->list); 316 spin_unlock(&pipe->lock); 317 pipe->ops->destroy_msg(msg); 318 } 319out_unlock: 320 inode_unlock(inode); 321 return res; 322} 323 324static ssize_t 325rpc_pipe_write(struct file *filp, const char __user *buf, size_t len, loff_t *offset) 326{ 327 struct inode *inode = file_inode(filp); 328 int res; 329 330 inode_lock(inode); 331 res = -EPIPE; 332 if (RPC_I(inode)->pipe != NULL) 333 res = RPC_I(inode)->pipe->ops->downcall(filp, buf, len); 334 inode_unlock(inode); 335 return res; 336} 337 338static __poll_t 339rpc_pipe_poll(struct file *filp, struct poll_table_struct *wait) 340{ 341 struct inode *inode = file_inode(filp); 342 struct rpc_inode *rpci = RPC_I(inode); 343 __poll_t mask = EPOLLOUT | EPOLLWRNORM; 344 345 poll_wait(filp, &rpci->waitq, wait); 346 347 inode_lock(inode); 348 if (rpci->pipe == NULL) 349 mask |= EPOLLERR | EPOLLHUP; 350 else if (filp->private_data || !list_empty(&rpci->pipe->pipe)) 351 mask |= EPOLLIN | EPOLLRDNORM; 352 inode_unlock(inode); 353 return mask; 354} 355 356static long 357rpc_pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg) 358{ 359 struct inode *inode = file_inode(filp); 360 struct rpc_pipe *pipe; 361 int len; 362 363 switch (cmd) { 364 case FIONREAD: 365 inode_lock(inode); 366 pipe = RPC_I(inode)->pipe; 367 if (pipe == NULL) { 368 inode_unlock(inode); 369 return -EPIPE; 370 } 371 spin_lock(&pipe->lock); 372 len = pipe->pipelen; 373 if (filp->private_data) { 374 struct rpc_pipe_msg *msg; 375 msg = filp->private_data; 376 len += msg->len - msg->copied; 377 } 378 spin_unlock(&pipe->lock); 379 inode_unlock(inode); 380 return put_user(len, (int __user *)arg); 381 default: 382 return -EINVAL; 383 } 384} 385 386static const struct file_operations rpc_pipe_fops = { 387 .owner = THIS_MODULE, 388 .llseek = no_llseek, 389 .read = rpc_pipe_read, 390 .write = rpc_pipe_write, 391 .poll = rpc_pipe_poll, 392 .unlocked_ioctl = rpc_pipe_ioctl, 393 .open = rpc_pipe_open, 394 .release = rpc_pipe_release, 395}; 396 397static int 398rpc_show_info(struct seq_file *m, void *v) 399{ 400 struct rpc_clnt *clnt = m->private; 401 402 rcu_read_lock(); 403 seq_printf(m, "RPC server: %s\n", 404 rcu_dereference(clnt->cl_xprt)->servername); 405 seq_printf(m, "service: %s (%d) version %d\n", clnt->cl_program->name, 406 clnt->cl_prog, clnt->cl_vers); 407 seq_printf(m, "address: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR)); 408 seq_printf(m, "protocol: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_PROTO)); 409 seq_printf(m, "port: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_PORT)); 410 rcu_read_unlock(); 411 return 0; 412} 413 414static int 415rpc_info_open(struct inode *inode, struct file *file) 416{ 417 struct rpc_clnt *clnt = NULL; 418 int ret = single_open(file, rpc_show_info, NULL); 419 420 if (!ret) { 421 struct seq_file *m = file->private_data; 422 423 spin_lock(&file->f_path.dentry->d_lock); 424 if (!d_unhashed(file->f_path.dentry)) 425 clnt = RPC_I(inode)->private; 426 if (clnt != NULL && refcount_inc_not_zero(&clnt->cl_count)) { 427 spin_unlock(&file->f_path.dentry->d_lock); 428 m->private = clnt; 429 } else { 430 spin_unlock(&file->f_path.dentry->d_lock); 431 single_release(inode, file); 432 ret = -EINVAL; 433 } 434 } 435 return ret; 436} 437 438static int 439rpc_info_release(struct inode *inode, struct file *file) 440{ 441 struct seq_file *m = file->private_data; 442 struct rpc_clnt *clnt = (struct rpc_clnt *)m->private; 443 444 if (clnt) 445 rpc_release_client(clnt); 446 return single_release(inode, file); 447} 448 449static const struct file_operations rpc_info_operations = { 450 .owner = THIS_MODULE, 451 .open = rpc_info_open, 452 .read = seq_read, 453 .llseek = seq_lseek, 454 .release = rpc_info_release, 455}; 456 457 458/* 459 * Description of fs contents. 460 */ 461struct rpc_filelist { 462 const char *name; 463 const struct file_operations *i_fop; 464 umode_t mode; 465}; 466 467static struct inode * 468rpc_get_inode(struct super_block *sb, umode_t mode) 469{ 470 struct inode *inode = new_inode(sb); 471 if (!inode) 472 return NULL; 473 inode->i_ino = get_next_ino(); 474 inode->i_mode = mode; 475 simple_inode_init_ts(inode); 476 switch (mode & S_IFMT) { 477 case S_IFDIR: 478 inode->i_fop = &simple_dir_operations; 479 inode->i_op = &simple_dir_inode_operations; 480 inc_nlink(inode); 481 break; 482 default: 483 break; 484 } 485 return inode; 486} 487 488static int __rpc_create_common(struct inode *dir, struct dentry *dentry, 489 umode_t mode, 490 const struct file_operations *i_fop, 491 void *private) 492{ 493 struct inode *inode; 494 495 d_drop(dentry); 496 inode = rpc_get_inode(dir->i_sb, mode); 497 if (!inode) 498 goto out_err; 499 inode->i_ino = iunique(dir->i_sb, 100); 500 if (i_fop) 501 inode->i_fop = i_fop; 502 if (private) 503 rpc_inode_setowner(inode, private); 504 d_add(dentry, inode); 505 return 0; 506out_err: 507 printk(KERN_WARNING "%s: %s failed to allocate inode for dentry %pd\n", 508 __FILE__, __func__, dentry); 509 dput(dentry); 510 return -ENOMEM; 511} 512 513static int __rpc_create(struct inode *dir, struct dentry *dentry, 514 umode_t mode, 515 const struct file_operations *i_fop, 516 void *private) 517{ 518 int err; 519 520 err = __rpc_create_common(dir, dentry, S_IFREG | mode, i_fop, private); 521 if (err) 522 return err; 523 fsnotify_create(dir, dentry); 524 return 0; 525} 526 527static int __rpc_mkdir(struct inode *dir, struct dentry *dentry, 528 umode_t mode, 529 const struct file_operations *i_fop, 530 void *private) 531{ 532 int err; 533 534 err = __rpc_create_common(dir, dentry, S_IFDIR | mode, i_fop, private); 535 if (err) 536 return err; 537 inc_nlink(dir); 538 fsnotify_mkdir(dir, dentry); 539 return 0; 540} 541 542static void 543init_pipe(struct rpc_pipe *pipe) 544{ 545 pipe->nreaders = 0; 546 pipe->nwriters = 0; 547 INIT_LIST_HEAD(&pipe->in_upcall); 548 INIT_LIST_HEAD(&pipe->in_downcall); 549 INIT_LIST_HEAD(&pipe->pipe); 550 pipe->pipelen = 0; 551 INIT_DELAYED_WORK(&pipe->queue_timeout, 552 rpc_timeout_upcall_queue); 553 pipe->ops = NULL; 554 spin_lock_init(&pipe->lock); 555 pipe->dentry = NULL; 556} 557 558void rpc_destroy_pipe_data(struct rpc_pipe *pipe) 559{ 560 kfree(pipe); 561} 562EXPORT_SYMBOL_GPL(rpc_destroy_pipe_data); 563 564struct rpc_pipe *rpc_mkpipe_data(const struct rpc_pipe_ops *ops, int flags) 565{ 566 struct rpc_pipe *pipe; 567 568 pipe = kzalloc(sizeof(struct rpc_pipe), GFP_KERNEL); 569 if (!pipe) 570 return ERR_PTR(-ENOMEM); 571 init_pipe(pipe); 572 pipe->ops = ops; 573 pipe->flags = flags; 574 return pipe; 575} 576EXPORT_SYMBOL_GPL(rpc_mkpipe_data); 577 578static int __rpc_mkpipe_dentry(struct inode *dir, struct dentry *dentry, 579 umode_t mode, 580 const struct file_operations *i_fop, 581 void *private, 582 struct rpc_pipe *pipe) 583{ 584 struct rpc_inode *rpci; 585 int err; 586 587 err = __rpc_create_common(dir, dentry, S_IFIFO | mode, i_fop, private); 588 if (err) 589 return err; 590 rpci = RPC_I(d_inode(dentry)); 591 rpci->private = private; 592 rpci->pipe = pipe; 593 fsnotify_create(dir, dentry); 594 return 0; 595} 596 597static int __rpc_rmdir(struct inode *dir, struct dentry *dentry) 598{ 599 int ret; 600 601 dget(dentry); 602 ret = simple_rmdir(dir, dentry); 603 d_drop(dentry); 604 if (!ret) 605 fsnotify_rmdir(dir, dentry); 606 dput(dentry); 607 return ret; 608} 609 610static int __rpc_unlink(struct inode *dir, struct dentry *dentry) 611{ 612 int ret; 613 614 dget(dentry); 615 ret = simple_unlink(dir, dentry); 616 d_drop(dentry); 617 if (!ret) 618 fsnotify_unlink(dir, dentry); 619 dput(dentry); 620 return ret; 621} 622 623static int __rpc_rmpipe(struct inode *dir, struct dentry *dentry) 624{ 625 struct inode *inode = d_inode(dentry); 626 627 rpc_close_pipes(inode); 628 return __rpc_unlink(dir, dentry); 629} 630 631static struct dentry *__rpc_lookup_create_exclusive(struct dentry *parent, 632 const char *name) 633{ 634 struct qstr q = QSTR_INIT(name, strlen(name)); 635 struct dentry *dentry = d_hash_and_lookup(parent, &q); 636 if (!dentry) { 637 dentry = d_alloc(parent, &q); 638 if (!dentry) 639 return ERR_PTR(-ENOMEM); 640 } 641 if (d_really_is_negative(dentry)) 642 return dentry; 643 dput(dentry); 644 return ERR_PTR(-EEXIST); 645} 646 647/* 648 * FIXME: This probably has races. 649 */ 650static void __rpc_depopulate(struct dentry *parent, 651 const struct rpc_filelist *files, 652 int start, int eof) 653{ 654 struct inode *dir = d_inode(parent); 655 struct dentry *dentry; 656 struct qstr name; 657 int i; 658 659 for (i = start; i < eof; i++) { 660 name.name = files[i].name; 661 name.len = strlen(files[i].name); 662 dentry = d_hash_and_lookup(parent, &name); 663 664 if (dentry == NULL) 665 continue; 666 if (d_really_is_negative(dentry)) 667 goto next; 668 switch (d_inode(dentry)->i_mode & S_IFMT) { 669 default: 670 BUG(); 671 case S_IFREG: 672 __rpc_unlink(dir, dentry); 673 break; 674 case S_IFDIR: 675 __rpc_rmdir(dir, dentry); 676 } 677next: 678 dput(dentry); 679 } 680} 681 682static void rpc_depopulate(struct dentry *parent, 683 const struct rpc_filelist *files, 684 int start, int eof) 685{ 686 struct inode *dir = d_inode(parent); 687 688 inode_lock_nested(dir, I_MUTEX_CHILD); 689 __rpc_depopulate(parent, files, start, eof); 690 inode_unlock(dir); 691} 692 693static int rpc_populate(struct dentry *parent, 694 const struct rpc_filelist *files, 695 int start, int eof, 696 void *private) 697{ 698 struct inode *dir = d_inode(parent); 699 struct dentry *dentry; 700 int i, err; 701 702 inode_lock(dir); 703 for (i = start; i < eof; i++) { 704 dentry = __rpc_lookup_create_exclusive(parent, files[i].name); 705 err = PTR_ERR(dentry); 706 if (IS_ERR(dentry)) 707 goto out_bad; 708 switch (files[i].mode & S_IFMT) { 709 default: 710 BUG(); 711 case S_IFREG: 712 err = __rpc_create(dir, dentry, 713 files[i].mode, 714 files[i].i_fop, 715 private); 716 break; 717 case S_IFDIR: 718 err = __rpc_mkdir(dir, dentry, 719 files[i].mode, 720 NULL, 721 private); 722 } 723 if (err != 0) 724 goto out_bad; 725 } 726 inode_unlock(dir); 727 return 0; 728out_bad: 729 __rpc_depopulate(parent, files, start, eof); 730 inode_unlock(dir); 731 printk(KERN_WARNING "%s: %s failed to populate directory %pd\n", 732 __FILE__, __func__, parent); 733 return err; 734} 735 736static struct dentry *rpc_mkdir_populate(struct dentry *parent, 737 const char *name, umode_t mode, void *private, 738 int (*populate)(struct dentry *, void *), void *args_populate) 739{ 740 struct dentry *dentry; 741 struct inode *dir = d_inode(parent); 742 int error; 743 744 inode_lock_nested(dir, I_MUTEX_PARENT); 745 dentry = __rpc_lookup_create_exclusive(parent, name); 746 if (IS_ERR(dentry)) 747 goto out; 748 error = __rpc_mkdir(dir, dentry, mode, NULL, private); 749 if (error != 0) 750 goto out_err; 751 if (populate != NULL) { 752 error = populate(dentry, args_populate); 753 if (error) 754 goto err_rmdir; 755 } 756out: 757 inode_unlock(dir); 758 return dentry; 759err_rmdir: 760 __rpc_rmdir(dir, dentry); 761out_err: 762 dentry = ERR_PTR(error); 763 goto out; 764} 765 766static int rpc_rmdir_depopulate(struct dentry *dentry, 767 void (*depopulate)(struct dentry *)) 768{ 769 struct dentry *parent; 770 struct inode *dir; 771 int error; 772 773 parent = dget_parent(dentry); 774 dir = d_inode(parent); 775 inode_lock_nested(dir, I_MUTEX_PARENT); 776 if (depopulate != NULL) 777 depopulate(dentry); 778 error = __rpc_rmdir(dir, dentry); 779 inode_unlock(dir); 780 dput(parent); 781 return error; 782} 783 784/** 785 * rpc_mkpipe_dentry - make an rpc_pipefs file for kernel<->userspace 786 * communication 787 * @parent: dentry of directory to create new "pipe" in 788 * @name: name of pipe 789 * @private: private data to associate with the pipe, for the caller's use 790 * @pipe: &rpc_pipe containing input parameters 791 * 792 * Data is made available for userspace to read by calls to 793 * rpc_queue_upcall(). The actual reads will result in calls to 794 * @ops->upcall, which will be called with the file pointer, 795 * message, and userspace buffer to copy to. 796 * 797 * Writes can come at any time, and do not necessarily have to be 798 * responses to upcalls. They will result in calls to @msg->downcall. 799 * 800 * The @private argument passed here will be available to all these methods 801 * from the file pointer, via RPC_I(file_inode(file))->private. 802 */ 803struct dentry *rpc_mkpipe_dentry(struct dentry *parent, const char *name, 804 void *private, struct rpc_pipe *pipe) 805{ 806 struct dentry *dentry; 807 struct inode *dir = d_inode(parent); 808 umode_t umode = S_IFIFO | 0600; 809 int err; 810 811 if (pipe->ops->upcall == NULL) 812 umode &= ~0444; 813 if (pipe->ops->downcall == NULL) 814 umode &= ~0222; 815 816 inode_lock_nested(dir, I_MUTEX_PARENT); 817 dentry = __rpc_lookup_create_exclusive(parent, name); 818 if (IS_ERR(dentry)) 819 goto out; 820 err = __rpc_mkpipe_dentry(dir, dentry, umode, &rpc_pipe_fops, 821 private, pipe); 822 if (err) 823 goto out_err; 824out: 825 inode_unlock(dir); 826 return dentry; 827out_err: 828 dentry = ERR_PTR(err); 829 printk(KERN_WARNING "%s: %s() failed to create pipe %pd/%s (errno = %d)\n", 830 __FILE__, __func__, parent, name, 831 err); 832 goto out; 833} 834EXPORT_SYMBOL_GPL(rpc_mkpipe_dentry); 835 836/** 837 * rpc_unlink - remove a pipe 838 * @dentry: dentry for the pipe, as returned from rpc_mkpipe 839 * 840 * After this call, lookups will no longer find the pipe, and any 841 * attempts to read or write using preexisting opens of the pipe will 842 * return -EPIPE. 843 */ 844int 845rpc_unlink(struct dentry *dentry) 846{ 847 struct dentry *parent; 848 struct inode *dir; 849 int error = 0; 850 851 parent = dget_parent(dentry); 852 dir = d_inode(parent); 853 inode_lock_nested(dir, I_MUTEX_PARENT); 854 error = __rpc_rmpipe(dir, dentry); 855 inode_unlock(dir); 856 dput(parent); 857 return error; 858} 859EXPORT_SYMBOL_GPL(rpc_unlink); 860 861/** 862 * rpc_init_pipe_dir_head - initialise a struct rpc_pipe_dir_head 863 * @pdh: pointer to struct rpc_pipe_dir_head 864 */ 865void rpc_init_pipe_dir_head(struct rpc_pipe_dir_head *pdh) 866{ 867 INIT_LIST_HEAD(&pdh->pdh_entries); 868 pdh->pdh_dentry = NULL; 869} 870EXPORT_SYMBOL_GPL(rpc_init_pipe_dir_head); 871 872/** 873 * rpc_init_pipe_dir_object - initialise a struct rpc_pipe_dir_object 874 * @pdo: pointer to struct rpc_pipe_dir_object 875 * @pdo_ops: pointer to const struct rpc_pipe_dir_object_ops 876 * @pdo_data: pointer to caller-defined data 877 */ 878void rpc_init_pipe_dir_object(struct rpc_pipe_dir_object *pdo, 879 const struct rpc_pipe_dir_object_ops *pdo_ops, 880 void *pdo_data) 881{ 882 INIT_LIST_HEAD(&pdo->pdo_head); 883 pdo->pdo_ops = pdo_ops; 884 pdo->pdo_data = pdo_data; 885} 886EXPORT_SYMBOL_GPL(rpc_init_pipe_dir_object); 887 888static int 889rpc_add_pipe_dir_object_locked(struct net *net, 890 struct rpc_pipe_dir_head *pdh, 891 struct rpc_pipe_dir_object *pdo) 892{ 893 int ret = 0; 894 895 if (pdh->pdh_dentry) 896 ret = pdo->pdo_ops->create(pdh->pdh_dentry, pdo); 897 if (ret == 0) 898 list_add_tail(&pdo->pdo_head, &pdh->pdh_entries); 899 return ret; 900} 901 902static void 903rpc_remove_pipe_dir_object_locked(struct net *net, 904 struct rpc_pipe_dir_head *pdh, 905 struct rpc_pipe_dir_object *pdo) 906{ 907 if (pdh->pdh_dentry) 908 pdo->pdo_ops->destroy(pdh->pdh_dentry, pdo); 909 list_del_init(&pdo->pdo_head); 910} 911 912/** 913 * rpc_add_pipe_dir_object - associate a rpc_pipe_dir_object to a directory 914 * @net: pointer to struct net 915 * @pdh: pointer to struct rpc_pipe_dir_head 916 * @pdo: pointer to struct rpc_pipe_dir_object 917 * 918 */ 919int 920rpc_add_pipe_dir_object(struct net *net, 921 struct rpc_pipe_dir_head *pdh, 922 struct rpc_pipe_dir_object *pdo) 923{ 924 int ret = 0; 925 926 if (list_empty(&pdo->pdo_head)) { 927 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 928 929 mutex_lock(&sn->pipefs_sb_lock); 930 ret = rpc_add_pipe_dir_object_locked(net, pdh, pdo); 931 mutex_unlock(&sn->pipefs_sb_lock); 932 } 933 return ret; 934} 935EXPORT_SYMBOL_GPL(rpc_add_pipe_dir_object); 936 937/** 938 * rpc_remove_pipe_dir_object - remove a rpc_pipe_dir_object from a directory 939 * @net: pointer to struct net 940 * @pdh: pointer to struct rpc_pipe_dir_head 941 * @pdo: pointer to struct rpc_pipe_dir_object 942 * 943 */ 944void 945rpc_remove_pipe_dir_object(struct net *net, 946 struct rpc_pipe_dir_head *pdh, 947 struct rpc_pipe_dir_object *pdo) 948{ 949 if (!list_empty(&pdo->pdo_head)) { 950 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 951 952 mutex_lock(&sn->pipefs_sb_lock); 953 rpc_remove_pipe_dir_object_locked(net, pdh, pdo); 954 mutex_unlock(&sn->pipefs_sb_lock); 955 } 956} 957EXPORT_SYMBOL_GPL(rpc_remove_pipe_dir_object); 958 959/** 960 * rpc_find_or_alloc_pipe_dir_object 961 * @net: pointer to struct net 962 * @pdh: pointer to struct rpc_pipe_dir_head 963 * @match: match struct rpc_pipe_dir_object to data 964 * @alloc: allocate a new struct rpc_pipe_dir_object 965 * @data: user defined data for match() and alloc() 966 * 967 */ 968struct rpc_pipe_dir_object * 969rpc_find_or_alloc_pipe_dir_object(struct net *net, 970 struct rpc_pipe_dir_head *pdh, 971 int (*match)(struct rpc_pipe_dir_object *, void *), 972 struct rpc_pipe_dir_object *(*alloc)(void *), 973 void *data) 974{ 975 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 976 struct rpc_pipe_dir_object *pdo; 977 978 mutex_lock(&sn->pipefs_sb_lock); 979 list_for_each_entry(pdo, &pdh->pdh_entries, pdo_head) { 980 if (!match(pdo, data)) 981 continue; 982 goto out; 983 } 984 pdo = alloc(data); 985 if (!pdo) 986 goto out; 987 rpc_add_pipe_dir_object_locked(net, pdh, pdo); 988out: 989 mutex_unlock(&sn->pipefs_sb_lock); 990 return pdo; 991} 992EXPORT_SYMBOL_GPL(rpc_find_or_alloc_pipe_dir_object); 993 994static void 995rpc_create_pipe_dir_objects(struct rpc_pipe_dir_head *pdh) 996{ 997 struct rpc_pipe_dir_object *pdo; 998 struct dentry *dir = pdh->pdh_dentry; 999 1000 list_for_each_entry(pdo, &pdh->pdh_entries, pdo_head) 1001 pdo->pdo_ops->create(dir, pdo); 1002} 1003 1004static void 1005rpc_destroy_pipe_dir_objects(struct rpc_pipe_dir_head *pdh) 1006{ 1007 struct rpc_pipe_dir_object *pdo; 1008 struct dentry *dir = pdh->pdh_dentry; 1009 1010 list_for_each_entry(pdo, &pdh->pdh_entries, pdo_head) 1011 pdo->pdo_ops->destroy(dir, pdo); 1012} 1013 1014enum { 1015 RPCAUTH_info, 1016 RPCAUTH_EOF 1017}; 1018 1019static const struct rpc_filelist authfiles[] = { 1020 [RPCAUTH_info] = { 1021 .name = "info", 1022 .i_fop = &rpc_info_operations, 1023 .mode = S_IFREG | 0400, 1024 }, 1025}; 1026 1027static int rpc_clntdir_populate(struct dentry *dentry, void *private) 1028{ 1029 return rpc_populate(dentry, 1030 authfiles, RPCAUTH_info, RPCAUTH_EOF, 1031 private); 1032} 1033 1034static void rpc_clntdir_depopulate(struct dentry *dentry) 1035{ 1036 rpc_depopulate(dentry, authfiles, RPCAUTH_info, RPCAUTH_EOF); 1037} 1038 1039/** 1040 * rpc_create_client_dir - Create a new rpc_client directory in rpc_pipefs 1041 * @dentry: the parent of new directory 1042 * @name: the name of new directory 1043 * @rpc_client: rpc client to associate with this directory 1044 * 1045 * This creates a directory at the given @path associated with 1046 * @rpc_clnt, which will contain a file named "info" with some basic 1047 * information about the client, together with any "pipes" that may 1048 * later be created using rpc_mkpipe(). 1049 */ 1050struct dentry *rpc_create_client_dir(struct dentry *dentry, 1051 const char *name, 1052 struct rpc_clnt *rpc_client) 1053{ 1054 struct dentry *ret; 1055 1056 ret = rpc_mkdir_populate(dentry, name, 0555, NULL, 1057 rpc_clntdir_populate, rpc_client); 1058 if (!IS_ERR(ret)) { 1059 rpc_client->cl_pipedir_objects.pdh_dentry = ret; 1060 rpc_create_pipe_dir_objects(&rpc_client->cl_pipedir_objects); 1061 } 1062 return ret; 1063} 1064 1065/** 1066 * rpc_remove_client_dir - Remove a directory created with rpc_create_client_dir() 1067 * @rpc_client: rpc_client for the pipe 1068 */ 1069int rpc_remove_client_dir(struct rpc_clnt *rpc_client) 1070{ 1071 struct dentry *dentry = rpc_client->cl_pipedir_objects.pdh_dentry; 1072 1073 if (dentry == NULL) 1074 return 0; 1075 rpc_destroy_pipe_dir_objects(&rpc_client->cl_pipedir_objects); 1076 rpc_client->cl_pipedir_objects.pdh_dentry = NULL; 1077 return rpc_rmdir_depopulate(dentry, rpc_clntdir_depopulate); 1078} 1079 1080static const struct rpc_filelist cache_pipefs_files[3] = { 1081 [0] = { 1082 .name = "channel", 1083 .i_fop = &cache_file_operations_pipefs, 1084 .mode = S_IFREG | 0600, 1085 }, 1086 [1] = { 1087 .name = "content", 1088 .i_fop = &content_file_operations_pipefs, 1089 .mode = S_IFREG | 0400, 1090 }, 1091 [2] = { 1092 .name = "flush", 1093 .i_fop = &cache_flush_operations_pipefs, 1094 .mode = S_IFREG | 0600, 1095 }, 1096}; 1097 1098static int rpc_cachedir_populate(struct dentry *dentry, void *private) 1099{ 1100 return rpc_populate(dentry, 1101 cache_pipefs_files, 0, 3, 1102 private); 1103} 1104 1105static void rpc_cachedir_depopulate(struct dentry *dentry) 1106{ 1107 rpc_depopulate(dentry, cache_pipefs_files, 0, 3); 1108} 1109 1110struct dentry *rpc_create_cache_dir(struct dentry *parent, const char *name, 1111 umode_t umode, struct cache_detail *cd) 1112{ 1113 return rpc_mkdir_populate(parent, name, umode, NULL, 1114 rpc_cachedir_populate, cd); 1115} 1116 1117void rpc_remove_cache_dir(struct dentry *dentry) 1118{ 1119 rpc_rmdir_depopulate(dentry, rpc_cachedir_depopulate); 1120} 1121 1122/* 1123 * populate the filesystem 1124 */ 1125static const struct super_operations s_ops = { 1126 .alloc_inode = rpc_alloc_inode, 1127 .free_inode = rpc_free_inode, 1128 .statfs = simple_statfs, 1129}; 1130 1131#define RPCAUTH_GSSMAGIC 0x67596969 1132 1133/* 1134 * We have a single directory with 1 node in it. 1135 */ 1136enum { 1137 RPCAUTH_lockd, 1138 RPCAUTH_mount, 1139 RPCAUTH_nfs, 1140 RPCAUTH_portmap, 1141 RPCAUTH_statd, 1142 RPCAUTH_nfsd4_cb, 1143 RPCAUTH_cache, 1144 RPCAUTH_nfsd, 1145 RPCAUTH_gssd, 1146 RPCAUTH_RootEOF 1147}; 1148 1149static const struct rpc_filelist files[] = { 1150 [RPCAUTH_lockd] = { 1151 .name = "lockd", 1152 .mode = S_IFDIR | 0555, 1153 }, 1154 [RPCAUTH_mount] = { 1155 .name = "mount", 1156 .mode = S_IFDIR | 0555, 1157 }, 1158 [RPCAUTH_nfs] = { 1159 .name = "nfs", 1160 .mode = S_IFDIR | 0555, 1161 }, 1162 [RPCAUTH_portmap] = { 1163 .name = "portmap", 1164 .mode = S_IFDIR | 0555, 1165 }, 1166 [RPCAUTH_statd] = { 1167 .name = "statd", 1168 .mode = S_IFDIR | 0555, 1169 }, 1170 [RPCAUTH_nfsd4_cb] = { 1171 .name = "nfsd4_cb", 1172 .mode = S_IFDIR | 0555, 1173 }, 1174 [RPCAUTH_cache] = { 1175 .name = "cache", 1176 .mode = S_IFDIR | 0555, 1177 }, 1178 [RPCAUTH_nfsd] = { 1179 .name = "nfsd", 1180 .mode = S_IFDIR | 0555, 1181 }, 1182 [RPCAUTH_gssd] = { 1183 .name = "gssd", 1184 .mode = S_IFDIR | 0555, 1185 }, 1186}; 1187 1188/* 1189 * This call can be used only in RPC pipefs mount notification hooks. 1190 */ 1191struct dentry *rpc_d_lookup_sb(const struct super_block *sb, 1192 const unsigned char *dir_name) 1193{ 1194 struct qstr dir = QSTR_INIT(dir_name, strlen(dir_name)); 1195 return d_hash_and_lookup(sb->s_root, &dir); 1196} 1197EXPORT_SYMBOL_GPL(rpc_d_lookup_sb); 1198 1199int rpc_pipefs_init_net(struct net *net) 1200{ 1201 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1202 1203 sn->gssd_dummy = rpc_mkpipe_data(&gssd_dummy_pipe_ops, 0); 1204 if (IS_ERR(sn->gssd_dummy)) 1205 return PTR_ERR(sn->gssd_dummy); 1206 1207 mutex_init(&sn->pipefs_sb_lock); 1208 sn->pipe_version = -1; 1209 return 0; 1210} 1211 1212void rpc_pipefs_exit_net(struct net *net) 1213{ 1214 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1215 1216 rpc_destroy_pipe_data(sn->gssd_dummy); 1217} 1218 1219/* 1220 * This call will be used for per network namespace operations calls. 1221 * Note: Function will be returned with pipefs_sb_lock taken if superblock was 1222 * found. This lock have to be released by rpc_put_sb_net() when all operations 1223 * will be completed. 1224 */ 1225struct super_block *rpc_get_sb_net(const struct net *net) 1226{ 1227 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1228 1229 mutex_lock(&sn->pipefs_sb_lock); 1230 if (sn->pipefs_sb) 1231 return sn->pipefs_sb; 1232 mutex_unlock(&sn->pipefs_sb_lock); 1233 return NULL; 1234} 1235EXPORT_SYMBOL_GPL(rpc_get_sb_net); 1236 1237void rpc_put_sb_net(const struct net *net) 1238{ 1239 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1240 1241 WARN_ON(sn->pipefs_sb == NULL); 1242 mutex_unlock(&sn->pipefs_sb_lock); 1243} 1244EXPORT_SYMBOL_GPL(rpc_put_sb_net); 1245 1246static const struct rpc_filelist gssd_dummy_clnt_dir[] = { 1247 [0] = { 1248 .name = "clntXX", 1249 .mode = S_IFDIR | 0555, 1250 }, 1251}; 1252 1253static ssize_t 1254dummy_downcall(struct file *filp, const char __user *src, size_t len) 1255{ 1256 return -EINVAL; 1257} 1258 1259static const struct rpc_pipe_ops gssd_dummy_pipe_ops = { 1260 .upcall = rpc_pipe_generic_upcall, 1261 .downcall = dummy_downcall, 1262}; 1263 1264/* 1265 * Here we present a bogus "info" file to keep rpc.gssd happy. We don't expect 1266 * that it will ever use this info to handle an upcall, but rpc.gssd expects 1267 * that this file will be there and have a certain format. 1268 */ 1269static int 1270rpc_dummy_info_show(struct seq_file *m, void *v) 1271{ 1272 seq_printf(m, "RPC server: %s\n", utsname()->nodename); 1273 seq_printf(m, "service: foo (1) version 0\n"); 1274 seq_printf(m, "address: 127.0.0.1\n"); 1275 seq_printf(m, "protocol: tcp\n"); 1276 seq_printf(m, "port: 0\n"); 1277 return 0; 1278} 1279DEFINE_SHOW_ATTRIBUTE(rpc_dummy_info); 1280 1281static const struct rpc_filelist gssd_dummy_info_file[] = { 1282 [0] = { 1283 .name = "info", 1284 .i_fop = &rpc_dummy_info_fops, 1285 .mode = S_IFREG | 0400, 1286 }, 1287}; 1288 1289/** 1290 * rpc_gssd_dummy_populate - create a dummy gssd pipe 1291 * @root: root of the rpc_pipefs filesystem 1292 * @pipe_data: pipe data created when netns is initialized 1293 * 1294 * Create a dummy set of directories and a pipe that gssd can hold open to 1295 * indicate that it is up and running. 1296 */ 1297static struct dentry * 1298rpc_gssd_dummy_populate(struct dentry *root, struct rpc_pipe *pipe_data) 1299{ 1300 int ret = 0; 1301 struct dentry *gssd_dentry; 1302 struct dentry *clnt_dentry = NULL; 1303 struct dentry *pipe_dentry = NULL; 1304 struct qstr q = QSTR_INIT(files[RPCAUTH_gssd].name, 1305 strlen(files[RPCAUTH_gssd].name)); 1306 1307 /* We should never get this far if "gssd" doesn't exist */ 1308 gssd_dentry = d_hash_and_lookup(root, &q); 1309 if (!gssd_dentry) 1310 return ERR_PTR(-ENOENT); 1311 1312 ret = rpc_populate(gssd_dentry, gssd_dummy_clnt_dir, 0, 1, NULL); 1313 if (ret) { 1314 pipe_dentry = ERR_PTR(ret); 1315 goto out; 1316 } 1317 1318 q.name = gssd_dummy_clnt_dir[0].name; 1319 q.len = strlen(gssd_dummy_clnt_dir[0].name); 1320 clnt_dentry = d_hash_and_lookup(gssd_dentry, &q); 1321 if (!clnt_dentry) { 1322 __rpc_depopulate(gssd_dentry, gssd_dummy_clnt_dir, 0, 1); 1323 pipe_dentry = ERR_PTR(-ENOENT); 1324 goto out; 1325 } 1326 1327 ret = rpc_populate(clnt_dentry, gssd_dummy_info_file, 0, 1, NULL); 1328 if (ret) { 1329 __rpc_depopulate(gssd_dentry, gssd_dummy_clnt_dir, 0, 1); 1330 pipe_dentry = ERR_PTR(ret); 1331 goto out; 1332 } 1333 1334 pipe_dentry = rpc_mkpipe_dentry(clnt_dentry, "gssd", NULL, pipe_data); 1335 if (IS_ERR(pipe_dentry)) { 1336 __rpc_depopulate(clnt_dentry, gssd_dummy_info_file, 0, 1); 1337 __rpc_depopulate(gssd_dentry, gssd_dummy_clnt_dir, 0, 1); 1338 } 1339out: 1340 dput(clnt_dentry); 1341 dput(gssd_dentry); 1342 return pipe_dentry; 1343} 1344 1345static void 1346rpc_gssd_dummy_depopulate(struct dentry *pipe_dentry) 1347{ 1348 struct dentry *clnt_dir = pipe_dentry->d_parent; 1349 struct dentry *gssd_dir = clnt_dir->d_parent; 1350 1351 dget(pipe_dentry); 1352 __rpc_rmpipe(d_inode(clnt_dir), pipe_dentry); 1353 __rpc_depopulate(clnt_dir, gssd_dummy_info_file, 0, 1); 1354 __rpc_depopulate(gssd_dir, gssd_dummy_clnt_dir, 0, 1); 1355 dput(pipe_dentry); 1356} 1357 1358static int 1359rpc_fill_super(struct super_block *sb, struct fs_context *fc) 1360{ 1361 struct inode *inode; 1362 struct dentry *root, *gssd_dentry; 1363 struct net *net = sb->s_fs_info; 1364 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1365 int err; 1366 1367 sb->s_blocksize = PAGE_SIZE; 1368 sb->s_blocksize_bits = PAGE_SHIFT; 1369 sb->s_magic = RPCAUTH_GSSMAGIC; 1370 sb->s_op = &s_ops; 1371 sb->s_d_op = &simple_dentry_operations; 1372 sb->s_time_gran = 1; 1373 1374 inode = rpc_get_inode(sb, S_IFDIR | 0555); 1375 sb->s_root = root = d_make_root(inode); 1376 if (!root) 1377 return -ENOMEM; 1378 if (rpc_populate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF, NULL)) 1379 return -ENOMEM; 1380 1381 gssd_dentry = rpc_gssd_dummy_populate(root, sn->gssd_dummy); 1382 if (IS_ERR(gssd_dentry)) { 1383 __rpc_depopulate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF); 1384 return PTR_ERR(gssd_dentry); 1385 } 1386 1387 dprintk("RPC: sending pipefs MOUNT notification for net %x%s\n", 1388 net->ns.inum, NET_NAME(net)); 1389 mutex_lock(&sn->pipefs_sb_lock); 1390 sn->pipefs_sb = sb; 1391 err = blocking_notifier_call_chain(&rpc_pipefs_notifier_list, 1392 RPC_PIPEFS_MOUNT, 1393 sb); 1394 if (err) 1395 goto err_depopulate; 1396 mutex_unlock(&sn->pipefs_sb_lock); 1397 return 0; 1398 1399err_depopulate: 1400 rpc_gssd_dummy_depopulate(gssd_dentry); 1401 blocking_notifier_call_chain(&rpc_pipefs_notifier_list, 1402 RPC_PIPEFS_UMOUNT, 1403 sb); 1404 sn->pipefs_sb = NULL; 1405 __rpc_depopulate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF); 1406 mutex_unlock(&sn->pipefs_sb_lock); 1407 return err; 1408} 1409 1410bool 1411gssd_running(struct net *net) 1412{ 1413 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1414 struct rpc_pipe *pipe = sn->gssd_dummy; 1415 1416 return pipe->nreaders || pipe->nwriters; 1417} 1418EXPORT_SYMBOL_GPL(gssd_running); 1419 1420static int rpc_fs_get_tree(struct fs_context *fc) 1421{ 1422 return get_tree_keyed(fc, rpc_fill_super, get_net(fc->net_ns)); 1423} 1424 1425static void rpc_fs_free_fc(struct fs_context *fc) 1426{ 1427 if (fc->s_fs_info) 1428 put_net(fc->s_fs_info); 1429} 1430 1431static const struct fs_context_operations rpc_fs_context_ops = { 1432 .free = rpc_fs_free_fc, 1433 .get_tree = rpc_fs_get_tree, 1434}; 1435 1436static int rpc_init_fs_context(struct fs_context *fc) 1437{ 1438 put_user_ns(fc->user_ns); 1439 fc->user_ns = get_user_ns(fc->net_ns->user_ns); 1440 fc->ops = &rpc_fs_context_ops; 1441 return 0; 1442} 1443 1444static void rpc_kill_sb(struct super_block *sb) 1445{ 1446 struct net *net = sb->s_fs_info; 1447 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id); 1448 1449 mutex_lock(&sn->pipefs_sb_lock); 1450 if (sn->pipefs_sb != sb) { 1451 mutex_unlock(&sn->pipefs_sb_lock); 1452 goto out; 1453 } 1454 sn->pipefs_sb = NULL; 1455 dprintk("RPC: sending pipefs UMOUNT notification for net %x%s\n", 1456 net->ns.inum, NET_NAME(net)); 1457 blocking_notifier_call_chain(&rpc_pipefs_notifier_list, 1458 RPC_PIPEFS_UMOUNT, 1459 sb); 1460 mutex_unlock(&sn->pipefs_sb_lock); 1461out: 1462 kill_litter_super(sb); 1463 put_net(net); 1464} 1465 1466static struct file_system_type rpc_pipe_fs_type = { 1467 .owner = THIS_MODULE, 1468 .name = "rpc_pipefs", 1469 .init_fs_context = rpc_init_fs_context, 1470 .kill_sb = rpc_kill_sb, 1471}; 1472MODULE_ALIAS_FS("rpc_pipefs"); 1473MODULE_ALIAS("rpc_pipefs"); 1474 1475static void 1476init_once(void *foo) 1477{ 1478 struct rpc_inode *rpci = (struct rpc_inode *) foo; 1479 1480 inode_init_once(&rpci->vfs_inode); 1481 rpci->private = NULL; 1482 rpci->pipe = NULL; 1483 init_waitqueue_head(&rpci->waitq); 1484} 1485 1486int register_rpc_pipefs(void) 1487{ 1488 int err; 1489 1490 rpc_inode_cachep = kmem_cache_create("rpc_inode_cache", 1491 sizeof(struct rpc_inode), 1492 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| 1493 SLAB_ACCOUNT), 1494 init_once); 1495 if (!rpc_inode_cachep) 1496 return -ENOMEM; 1497 err = rpc_clients_notifier_register(); 1498 if (err) 1499 goto err_notifier; 1500 err = register_filesystem(&rpc_pipe_fs_type); 1501 if (err) 1502 goto err_register; 1503 return 0; 1504 1505err_register: 1506 rpc_clients_notifier_unregister(); 1507err_notifier: 1508 kmem_cache_destroy(rpc_inode_cachep); 1509 return err; 1510} 1511 1512void unregister_rpc_pipefs(void) 1513{ 1514 rpc_clients_notifier_unregister(); 1515 unregister_filesystem(&rpc_pipe_fs_type); 1516 kmem_cache_destroy(rpc_inode_cachep); 1517} 1518