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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_cond_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 = kmem_cache_alloc(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 && atomic_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 inode->i_atime = inode->i_mtime = inode->i_ctime = current_time(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 default:
482 break;
483 }
484 return inode;
485}
486
487static int __rpc_create_common(struct inode *dir, struct dentry *dentry,
488 umode_t mode,
489 const struct file_operations *i_fop,
490 void *private)
491{
492 struct inode *inode;
493
494 d_drop(dentry);
495 inode = rpc_get_inode(dir->i_sb, mode);
496 if (!inode)
497 goto out_err;
498 inode->i_ino = iunique(dir->i_sb, 100);
499 if (i_fop)
500 inode->i_fop = i_fop;
501 if (private)
502 rpc_inode_setowner(inode, private);
503 d_add(dentry, inode);
504 return 0;
505out_err:
506 printk(KERN_WARNING "%s: %s failed to allocate inode for dentry %pd\n",
507 __FILE__, __func__, dentry);
508 dput(dentry);
509 return -ENOMEM;
510}
511
512static int __rpc_create(struct inode *dir, struct dentry *dentry,
513 umode_t mode,
514 const struct file_operations *i_fop,
515 void *private)
516{
517 int err;
518
519 err = __rpc_create_common(dir, dentry, S_IFREG | mode, i_fop, private);
520 if (err)
521 return err;
522 fsnotify_create(dir, dentry);
523 return 0;
524}
525
526static int __rpc_mkdir(struct inode *dir, struct dentry *dentry,
527 umode_t mode,
528 const struct file_operations *i_fop,
529 void *private)
530{
531 int err;
532
533 err = __rpc_create_common(dir, dentry, S_IFDIR | mode, i_fop, private);
534 if (err)
535 return err;
536 inc_nlink(dir);
537 fsnotify_mkdir(dir, dentry);
538 return 0;
539}
540
541static void
542init_pipe(struct rpc_pipe *pipe)
543{
544 pipe->nreaders = 0;
545 pipe->nwriters = 0;
546 INIT_LIST_HEAD(&pipe->in_upcall);
547 INIT_LIST_HEAD(&pipe->in_downcall);
548 INIT_LIST_HEAD(&pipe->pipe);
549 pipe->pipelen = 0;
550 INIT_DELAYED_WORK(&pipe->queue_timeout,
551 rpc_timeout_upcall_queue);
552 pipe->ops = NULL;
553 spin_lock_init(&pipe->lock);
554 pipe->dentry = NULL;
555}
556
557void rpc_destroy_pipe_data(struct rpc_pipe *pipe)
558{
559 kfree(pipe);
560}
561EXPORT_SYMBOL_GPL(rpc_destroy_pipe_data);
562
563struct rpc_pipe *rpc_mkpipe_data(const struct rpc_pipe_ops *ops, int flags)
564{
565 struct rpc_pipe *pipe;
566
567 pipe = kzalloc(sizeof(struct rpc_pipe), GFP_KERNEL);
568 if (!pipe)
569 return ERR_PTR(-ENOMEM);
570 init_pipe(pipe);
571 pipe->ops = ops;
572 pipe->flags = flags;
573 return pipe;
574}
575EXPORT_SYMBOL_GPL(rpc_mkpipe_data);
576
577static int __rpc_mkpipe_dentry(struct inode *dir, struct dentry *dentry,
578 umode_t mode,
579 const struct file_operations *i_fop,
580 void *private,
581 struct rpc_pipe *pipe)
582{
583 struct rpc_inode *rpci;
584 int err;
585
586 err = __rpc_create_common(dir, dentry, S_IFIFO | mode, i_fop, private);
587 if (err)
588 return err;
589 rpci = RPC_I(d_inode(dentry));
590 rpci->private = private;
591 rpci->pipe = pipe;
592 fsnotify_create(dir, dentry);
593 return 0;
594}
595
596static int __rpc_rmdir(struct inode *dir, struct dentry *dentry)
597{
598 int ret;
599
600 dget(dentry);
601 ret = simple_rmdir(dir, dentry);
602 if (!ret)
603 fsnotify_rmdir(dir, dentry);
604 d_delete(dentry);
605 dput(dentry);
606 return ret;
607}
608
609static int __rpc_unlink(struct inode *dir, struct dentry *dentry)
610{
611 int ret;
612
613 dget(dentry);
614 ret = simple_unlink(dir, dentry);
615 if (!ret)
616 fsnotify_unlink(dir, dentry);
617 d_delete(dentry);
618 dput(dentry);
619 return ret;
620}
621
622static int __rpc_rmpipe(struct inode *dir, struct dentry *dentry)
623{
624 struct inode *inode = d_inode(dentry);
625
626 rpc_close_pipes(inode);
627 return __rpc_unlink(dir, dentry);
628}
629
630static struct dentry *__rpc_lookup_create_exclusive(struct dentry *parent,
631 const char *name)
632{
633 struct qstr q = QSTR_INIT(name, strlen(name));
634 struct dentry *dentry = d_hash_and_lookup(parent, &q);
635 if (!dentry) {
636 dentry = d_alloc(parent, &q);
637 if (!dentry)
638 return ERR_PTR(-ENOMEM);
639 }
640 if (d_really_is_negative(dentry))
641 return dentry;
642 dput(dentry);
643 return ERR_PTR(-EEXIST);
644}
645
646/*
647 * FIXME: This probably has races.
648 */
649static void __rpc_depopulate(struct dentry *parent,
650 const struct rpc_filelist *files,
651 int start, int eof)
652{
653 struct inode *dir = d_inode(parent);
654 struct dentry *dentry;
655 struct qstr name;
656 int i;
657
658 for (i = start; i < eof; i++) {
659 name.name = files[i].name;
660 name.len = strlen(files[i].name);
661 dentry = d_hash_and_lookup(parent, &name);
662
663 if (dentry == NULL)
664 continue;
665 if (d_really_is_negative(dentry))
666 goto next;
667 switch (d_inode(dentry)->i_mode & S_IFMT) {
668 default:
669 BUG();
670 case S_IFREG:
671 __rpc_unlink(dir, dentry);
672 break;
673 case S_IFDIR:
674 __rpc_rmdir(dir, dentry);
675 }
676next:
677 dput(dentry);
678 }
679}
680
681static void rpc_depopulate(struct dentry *parent,
682 const struct rpc_filelist *files,
683 int start, int eof)
684{
685 struct inode *dir = d_inode(parent);
686
687 inode_lock_nested(dir, I_MUTEX_CHILD);
688 __rpc_depopulate(parent, files, start, eof);
689 inode_unlock(dir);
690}
691
692static int rpc_populate(struct dentry *parent,
693 const struct rpc_filelist *files,
694 int start, int eof,
695 void *private)
696{
697 struct inode *dir = d_inode(parent);
698 struct dentry *dentry;
699 int i, err;
700
701 inode_lock(dir);
702 for (i = start; i < eof; i++) {
703 dentry = __rpc_lookup_create_exclusive(parent, files[i].name);
704 err = PTR_ERR(dentry);
705 if (IS_ERR(dentry))
706 goto out_bad;
707 switch (files[i].mode & S_IFMT) {
708 default:
709 BUG();
710 case S_IFREG:
711 err = __rpc_create(dir, dentry,
712 files[i].mode,
713 files[i].i_fop,
714 private);
715 break;
716 case S_IFDIR:
717 err = __rpc_mkdir(dir, dentry,
718 files[i].mode,
719 NULL,
720 private);
721 }
722 if (err != 0)
723 goto out_bad;
724 }
725 inode_unlock(dir);
726 return 0;
727out_bad:
728 __rpc_depopulate(parent, files, start, eof);
729 inode_unlock(dir);
730 printk(KERN_WARNING "%s: %s failed to populate directory %pd\n",
731 __FILE__, __func__, parent);
732 return err;
733}
734
735static struct dentry *rpc_mkdir_populate(struct dentry *parent,
736 const char *name, umode_t mode, void *private,
737 int (*populate)(struct dentry *, void *), void *args_populate)
738{
739 struct dentry *dentry;
740 struct inode *dir = d_inode(parent);
741 int error;
742
743 inode_lock_nested(dir, I_MUTEX_PARENT);
744 dentry = __rpc_lookup_create_exclusive(parent, name);
745 if (IS_ERR(dentry))
746 goto out;
747 error = __rpc_mkdir(dir, dentry, mode, NULL, private);
748 if (error != 0)
749 goto out_err;
750 if (populate != NULL) {
751 error = populate(dentry, args_populate);
752 if (error)
753 goto err_rmdir;
754 }
755out:
756 inode_unlock(dir);
757 return dentry;
758err_rmdir:
759 __rpc_rmdir(dir, dentry);
760out_err:
761 dentry = ERR_PTR(error);
762 goto out;
763}
764
765static int rpc_rmdir_depopulate(struct dentry *dentry,
766 void (*depopulate)(struct dentry *))
767{
768 struct dentry *parent;
769 struct inode *dir;
770 int error;
771
772 parent = dget_parent(dentry);
773 dir = d_inode(parent);
774 inode_lock_nested(dir, I_MUTEX_PARENT);
775 if (depopulate != NULL)
776 depopulate(dentry);
777 error = __rpc_rmdir(dir, dentry);
778 inode_unlock(dir);
779 dput(parent);
780 return error;
781}
782
783/**
784 * rpc_mkpipe - make an rpc_pipefs file for kernel<->userspace communication
785 * @parent: dentry of directory to create new "pipe" in
786 * @name: name of pipe
787 * @private: private data to associate with the pipe, for the caller's use
788 * @pipe: &rpc_pipe containing input parameters
789 *
790 * Data is made available for userspace to read by calls to
791 * rpc_queue_upcall(). The actual reads will result in calls to
792 * @ops->upcall, which will be called with the file pointer,
793 * message, and userspace buffer to copy to.
794 *
795 * Writes can come at any time, and do not necessarily have to be
796 * responses to upcalls. They will result in calls to @msg->downcall.
797 *
798 * The @private argument passed here will be available to all these methods
799 * from the file pointer, via RPC_I(file_inode(file))->private.
800 */
801struct dentry *rpc_mkpipe_dentry(struct dentry *parent, const char *name,
802 void *private, struct rpc_pipe *pipe)
803{
804 struct dentry *dentry;
805 struct inode *dir = d_inode(parent);
806 umode_t umode = S_IFIFO | 0600;
807 int err;
808
809 if (pipe->ops->upcall == NULL)
810 umode &= ~0444;
811 if (pipe->ops->downcall == NULL)
812 umode &= ~0222;
813
814 inode_lock_nested(dir, I_MUTEX_PARENT);
815 dentry = __rpc_lookup_create_exclusive(parent, name);
816 if (IS_ERR(dentry))
817 goto out;
818 err = __rpc_mkpipe_dentry(dir, dentry, umode, &rpc_pipe_fops,
819 private, pipe);
820 if (err)
821 goto out_err;
822out:
823 inode_unlock(dir);
824 return dentry;
825out_err:
826 dentry = ERR_PTR(err);
827 printk(KERN_WARNING "%s: %s() failed to create pipe %pd/%s (errno = %d)\n",
828 __FILE__, __func__, parent, name,
829 err);
830 goto out;
831}
832EXPORT_SYMBOL_GPL(rpc_mkpipe_dentry);
833
834/**
835 * rpc_unlink - remove a pipe
836 * @dentry: dentry for the pipe, as returned from rpc_mkpipe
837 *
838 * After this call, lookups will no longer find the pipe, and any
839 * attempts to read or write using preexisting opens of the pipe will
840 * return -EPIPE.
841 */
842int
843rpc_unlink(struct dentry *dentry)
844{
845 struct dentry *parent;
846 struct inode *dir;
847 int error = 0;
848
849 parent = dget_parent(dentry);
850 dir = d_inode(parent);
851 inode_lock_nested(dir, I_MUTEX_PARENT);
852 error = __rpc_rmpipe(dir, dentry);
853 inode_unlock(dir);
854 dput(parent);
855 return error;
856}
857EXPORT_SYMBOL_GPL(rpc_unlink);
858
859/**
860 * rpc_init_pipe_dir_head - initialise a struct rpc_pipe_dir_head
861 * @pdh: pointer to struct rpc_pipe_dir_head
862 */
863void rpc_init_pipe_dir_head(struct rpc_pipe_dir_head *pdh)
864{
865 INIT_LIST_HEAD(&pdh->pdh_entries);
866 pdh->pdh_dentry = NULL;
867}
868EXPORT_SYMBOL_GPL(rpc_init_pipe_dir_head);
869
870/**
871 * rpc_init_pipe_dir_object - initialise a struct rpc_pipe_dir_object
872 * @pdo: pointer to struct rpc_pipe_dir_object
873 * @pdo_ops: pointer to const struct rpc_pipe_dir_object_ops
874 * @pdo_data: pointer to caller-defined data
875 */
876void rpc_init_pipe_dir_object(struct rpc_pipe_dir_object *pdo,
877 const struct rpc_pipe_dir_object_ops *pdo_ops,
878 void *pdo_data)
879{
880 INIT_LIST_HEAD(&pdo->pdo_head);
881 pdo->pdo_ops = pdo_ops;
882 pdo->pdo_data = pdo_data;
883}
884EXPORT_SYMBOL_GPL(rpc_init_pipe_dir_object);
885
886static int
887rpc_add_pipe_dir_object_locked(struct net *net,
888 struct rpc_pipe_dir_head *pdh,
889 struct rpc_pipe_dir_object *pdo)
890{
891 int ret = 0;
892
893 if (pdh->pdh_dentry)
894 ret = pdo->pdo_ops->create(pdh->pdh_dentry, pdo);
895 if (ret == 0)
896 list_add_tail(&pdo->pdo_head, &pdh->pdh_entries);
897 return ret;
898}
899
900static void
901rpc_remove_pipe_dir_object_locked(struct net *net,
902 struct rpc_pipe_dir_head *pdh,
903 struct rpc_pipe_dir_object *pdo)
904{
905 if (pdh->pdh_dentry)
906 pdo->pdo_ops->destroy(pdh->pdh_dentry, pdo);
907 list_del_init(&pdo->pdo_head);
908}
909
910/**
911 * rpc_add_pipe_dir_object - associate a rpc_pipe_dir_object to a directory
912 * @net: pointer to struct net
913 * @pdh: pointer to struct rpc_pipe_dir_head
914 * @pdo: pointer to struct rpc_pipe_dir_object
915 *
916 */
917int
918rpc_add_pipe_dir_object(struct net *net,
919 struct rpc_pipe_dir_head *pdh,
920 struct rpc_pipe_dir_object *pdo)
921{
922 int ret = 0;
923
924 if (list_empty(&pdo->pdo_head)) {
925 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
926
927 mutex_lock(&sn->pipefs_sb_lock);
928 ret = rpc_add_pipe_dir_object_locked(net, pdh, pdo);
929 mutex_unlock(&sn->pipefs_sb_lock);
930 }
931 return ret;
932}
933EXPORT_SYMBOL_GPL(rpc_add_pipe_dir_object);
934
935/**
936 * rpc_remove_pipe_dir_object - remove a rpc_pipe_dir_object from a directory
937 * @net: pointer to struct net
938 * @pdh: pointer to struct rpc_pipe_dir_head
939 * @pdo: pointer to struct rpc_pipe_dir_object
940 *
941 */
942void
943rpc_remove_pipe_dir_object(struct net *net,
944 struct rpc_pipe_dir_head *pdh,
945 struct rpc_pipe_dir_object *pdo)
946{
947 if (!list_empty(&pdo->pdo_head)) {
948 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
949
950 mutex_lock(&sn->pipefs_sb_lock);
951 rpc_remove_pipe_dir_object_locked(net, pdh, pdo);
952 mutex_unlock(&sn->pipefs_sb_lock);
953 }
954}
955EXPORT_SYMBOL_GPL(rpc_remove_pipe_dir_object);
956
957/**
958 * rpc_find_or_alloc_pipe_dir_object
959 * @net: pointer to struct net
960 * @pdh: pointer to struct rpc_pipe_dir_head
961 * @match: match struct rpc_pipe_dir_object to data
962 * @alloc: allocate a new struct rpc_pipe_dir_object
963 * @data: user defined data for match() and alloc()
964 *
965 */
966struct rpc_pipe_dir_object *
967rpc_find_or_alloc_pipe_dir_object(struct net *net,
968 struct rpc_pipe_dir_head *pdh,
969 int (*match)(struct rpc_pipe_dir_object *, void *),
970 struct rpc_pipe_dir_object *(*alloc)(void *),
971 void *data)
972{
973 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
974 struct rpc_pipe_dir_object *pdo;
975
976 mutex_lock(&sn->pipefs_sb_lock);
977 list_for_each_entry(pdo, &pdh->pdh_entries, pdo_head) {
978 if (!match(pdo, data))
979 continue;
980 goto out;
981 }
982 pdo = alloc(data);
983 if (!pdo)
984 goto out;
985 rpc_add_pipe_dir_object_locked(net, pdh, pdo);
986out:
987 mutex_unlock(&sn->pipefs_sb_lock);
988 return pdo;
989}
990EXPORT_SYMBOL_GPL(rpc_find_or_alloc_pipe_dir_object);
991
992static void
993rpc_create_pipe_dir_objects(struct rpc_pipe_dir_head *pdh)
994{
995 struct rpc_pipe_dir_object *pdo;
996 struct dentry *dir = pdh->pdh_dentry;
997
998 list_for_each_entry(pdo, &pdh->pdh_entries, pdo_head)
999 pdo->pdo_ops->create(dir, pdo);
1000}
1001
1002static void
1003rpc_destroy_pipe_dir_objects(struct rpc_pipe_dir_head *pdh)
1004{
1005 struct rpc_pipe_dir_object *pdo;
1006 struct dentry *dir = pdh->pdh_dentry;
1007
1008 list_for_each_entry(pdo, &pdh->pdh_entries, pdo_head)
1009 pdo->pdo_ops->destroy(dir, pdo);
1010}
1011
1012enum {
1013 RPCAUTH_info,
1014 RPCAUTH_EOF
1015};
1016
1017static const struct rpc_filelist authfiles[] = {
1018 [RPCAUTH_info] = {
1019 .name = "info",
1020 .i_fop = &rpc_info_operations,
1021 .mode = S_IFREG | 0400,
1022 },
1023};
1024
1025static int rpc_clntdir_populate(struct dentry *dentry, void *private)
1026{
1027 return rpc_populate(dentry,
1028 authfiles, RPCAUTH_info, RPCAUTH_EOF,
1029 private);
1030}
1031
1032static void rpc_clntdir_depopulate(struct dentry *dentry)
1033{
1034 rpc_depopulate(dentry, authfiles, RPCAUTH_info, RPCAUTH_EOF);
1035}
1036
1037/**
1038 * rpc_create_client_dir - Create a new rpc_client directory in rpc_pipefs
1039 * @dentry: the parent of new directory
1040 * @name: the name of new directory
1041 * @rpc_client: rpc client to associate with this directory
1042 *
1043 * This creates a directory at the given @path associated with
1044 * @rpc_clnt, which will contain a file named "info" with some basic
1045 * information about the client, together with any "pipes" that may
1046 * later be created using rpc_mkpipe().
1047 */
1048struct dentry *rpc_create_client_dir(struct dentry *dentry,
1049 const char *name,
1050 struct rpc_clnt *rpc_client)
1051{
1052 struct dentry *ret;
1053
1054 ret = rpc_mkdir_populate(dentry, name, 0555, NULL,
1055 rpc_clntdir_populate, rpc_client);
1056 if (!IS_ERR(ret)) {
1057 rpc_client->cl_pipedir_objects.pdh_dentry = ret;
1058 rpc_create_pipe_dir_objects(&rpc_client->cl_pipedir_objects);
1059 }
1060 return ret;
1061}
1062
1063/**
1064 * rpc_remove_client_dir - Remove a directory created with rpc_create_client_dir()
1065 * @rpc_client: rpc_client for the pipe
1066 */
1067int rpc_remove_client_dir(struct rpc_clnt *rpc_client)
1068{
1069 struct dentry *dentry = rpc_client->cl_pipedir_objects.pdh_dentry;
1070
1071 if (dentry == NULL)
1072 return 0;
1073 rpc_destroy_pipe_dir_objects(&rpc_client->cl_pipedir_objects);
1074 rpc_client->cl_pipedir_objects.pdh_dentry = NULL;
1075 return rpc_rmdir_depopulate(dentry, rpc_clntdir_depopulate);
1076}
1077
1078static const struct rpc_filelist cache_pipefs_files[3] = {
1079 [0] = {
1080 .name = "channel",
1081 .i_fop = &cache_file_operations_pipefs,
1082 .mode = S_IFREG | 0600,
1083 },
1084 [1] = {
1085 .name = "content",
1086 .i_fop = &content_file_operations_pipefs,
1087 .mode = S_IFREG | 0400,
1088 },
1089 [2] = {
1090 .name = "flush",
1091 .i_fop = &cache_flush_operations_pipefs,
1092 .mode = S_IFREG | 0600,
1093 },
1094};
1095
1096static int rpc_cachedir_populate(struct dentry *dentry, void *private)
1097{
1098 return rpc_populate(dentry,
1099 cache_pipefs_files, 0, 3,
1100 private);
1101}
1102
1103static void rpc_cachedir_depopulate(struct dentry *dentry)
1104{
1105 rpc_depopulate(dentry, cache_pipefs_files, 0, 3);
1106}
1107
1108struct dentry *rpc_create_cache_dir(struct dentry *parent, const char *name,
1109 umode_t umode, struct cache_detail *cd)
1110{
1111 return rpc_mkdir_populate(parent, name, umode, NULL,
1112 rpc_cachedir_populate, cd);
1113}
1114
1115void rpc_remove_cache_dir(struct dentry *dentry)
1116{
1117 rpc_rmdir_depopulate(dentry, rpc_cachedir_depopulate);
1118}
1119
1120/*
1121 * populate the filesystem
1122 */
1123static const struct super_operations s_ops = {
1124 .alloc_inode = rpc_alloc_inode,
1125 .free_inode = rpc_free_inode,
1126 .statfs = simple_statfs,
1127};
1128
1129#define RPCAUTH_GSSMAGIC 0x67596969
1130
1131/*
1132 * We have a single directory with 1 node in it.
1133 */
1134enum {
1135 RPCAUTH_lockd,
1136 RPCAUTH_mount,
1137 RPCAUTH_nfs,
1138 RPCAUTH_portmap,
1139 RPCAUTH_statd,
1140 RPCAUTH_nfsd4_cb,
1141 RPCAUTH_cache,
1142 RPCAUTH_nfsd,
1143 RPCAUTH_gssd,
1144 RPCAUTH_RootEOF
1145};
1146
1147static const struct rpc_filelist files[] = {
1148 [RPCAUTH_lockd] = {
1149 .name = "lockd",
1150 .mode = S_IFDIR | 0555,
1151 },
1152 [RPCAUTH_mount] = {
1153 .name = "mount",
1154 .mode = S_IFDIR | 0555,
1155 },
1156 [RPCAUTH_nfs] = {
1157 .name = "nfs",
1158 .mode = S_IFDIR | 0555,
1159 },
1160 [RPCAUTH_portmap] = {
1161 .name = "portmap",
1162 .mode = S_IFDIR | 0555,
1163 },
1164 [RPCAUTH_statd] = {
1165 .name = "statd",
1166 .mode = S_IFDIR | 0555,
1167 },
1168 [RPCAUTH_nfsd4_cb] = {
1169 .name = "nfsd4_cb",
1170 .mode = S_IFDIR | 0555,
1171 },
1172 [RPCAUTH_cache] = {
1173 .name = "cache",
1174 .mode = S_IFDIR | 0555,
1175 },
1176 [RPCAUTH_nfsd] = {
1177 .name = "nfsd",
1178 .mode = S_IFDIR | 0555,
1179 },
1180 [RPCAUTH_gssd] = {
1181 .name = "gssd",
1182 .mode = S_IFDIR | 0555,
1183 },
1184};
1185
1186/*
1187 * This call can be used only in RPC pipefs mount notification hooks.
1188 */
1189struct dentry *rpc_d_lookup_sb(const struct super_block *sb,
1190 const unsigned char *dir_name)
1191{
1192 struct qstr dir = QSTR_INIT(dir_name, strlen(dir_name));
1193 return d_hash_and_lookup(sb->s_root, &dir);
1194}
1195EXPORT_SYMBOL_GPL(rpc_d_lookup_sb);
1196
1197int rpc_pipefs_init_net(struct net *net)
1198{
1199 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1200
1201 sn->gssd_dummy = rpc_mkpipe_data(&gssd_dummy_pipe_ops, 0);
1202 if (IS_ERR(sn->gssd_dummy))
1203 return PTR_ERR(sn->gssd_dummy);
1204
1205 mutex_init(&sn->pipefs_sb_lock);
1206 sn->pipe_version = -1;
1207 return 0;
1208}
1209
1210void rpc_pipefs_exit_net(struct net *net)
1211{
1212 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1213
1214 rpc_destroy_pipe_data(sn->gssd_dummy);
1215}
1216
1217/*
1218 * This call will be used for per network namespace operations calls.
1219 * Note: Function will be returned with pipefs_sb_lock taken if superblock was
1220 * found. This lock have to be released by rpc_put_sb_net() when all operations
1221 * will be completed.
1222 */
1223struct super_block *rpc_get_sb_net(const struct net *net)
1224{
1225 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1226
1227 mutex_lock(&sn->pipefs_sb_lock);
1228 if (sn->pipefs_sb)
1229 return sn->pipefs_sb;
1230 mutex_unlock(&sn->pipefs_sb_lock);
1231 return NULL;
1232}
1233EXPORT_SYMBOL_GPL(rpc_get_sb_net);
1234
1235void rpc_put_sb_net(const struct net *net)
1236{
1237 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1238
1239 WARN_ON(sn->pipefs_sb == NULL);
1240 mutex_unlock(&sn->pipefs_sb_lock);
1241}
1242EXPORT_SYMBOL_GPL(rpc_put_sb_net);
1243
1244static const struct rpc_filelist gssd_dummy_clnt_dir[] = {
1245 [0] = {
1246 .name = "clntXX",
1247 .mode = S_IFDIR | 0555,
1248 },
1249};
1250
1251static ssize_t
1252dummy_downcall(struct file *filp, const char __user *src, size_t len)
1253{
1254 return -EINVAL;
1255}
1256
1257static const struct rpc_pipe_ops gssd_dummy_pipe_ops = {
1258 .upcall = rpc_pipe_generic_upcall,
1259 .downcall = dummy_downcall,
1260};
1261
1262/*
1263 * Here we present a bogus "info" file to keep rpc.gssd happy. We don't expect
1264 * that it will ever use this info to handle an upcall, but rpc.gssd expects
1265 * that this file will be there and have a certain format.
1266 */
1267static int
1268rpc_dummy_info_show(struct seq_file *m, void *v)
1269{
1270 seq_printf(m, "RPC server: %s\n", utsname()->nodename);
1271 seq_printf(m, "service: foo (1) version 0\n");
1272 seq_printf(m, "address: 127.0.0.1\n");
1273 seq_printf(m, "protocol: tcp\n");
1274 seq_printf(m, "port: 0\n");
1275 return 0;
1276}
1277DEFINE_SHOW_ATTRIBUTE(rpc_dummy_info);
1278
1279static const struct rpc_filelist gssd_dummy_info_file[] = {
1280 [0] = {
1281 .name = "info",
1282 .i_fop = &rpc_dummy_info_fops,
1283 .mode = S_IFREG | 0400,
1284 },
1285};
1286
1287/**
1288 * rpc_gssd_dummy_populate - create a dummy gssd pipe
1289 * @root: root of the rpc_pipefs filesystem
1290 * @pipe_data: pipe data created when netns is initialized
1291 *
1292 * Create a dummy set of directories and a pipe that gssd can hold open to
1293 * indicate that it is up and running.
1294 */
1295static struct dentry *
1296rpc_gssd_dummy_populate(struct dentry *root, struct rpc_pipe *pipe_data)
1297{
1298 int ret = 0;
1299 struct dentry *gssd_dentry;
1300 struct dentry *clnt_dentry = NULL;
1301 struct dentry *pipe_dentry = NULL;
1302 struct qstr q = QSTR_INIT(files[RPCAUTH_gssd].name,
1303 strlen(files[RPCAUTH_gssd].name));
1304
1305 /* We should never get this far if "gssd" doesn't exist */
1306 gssd_dentry = d_hash_and_lookup(root, &q);
1307 if (!gssd_dentry)
1308 return ERR_PTR(-ENOENT);
1309
1310 ret = rpc_populate(gssd_dentry, gssd_dummy_clnt_dir, 0, 1, NULL);
1311 if (ret) {
1312 pipe_dentry = ERR_PTR(ret);
1313 goto out;
1314 }
1315
1316 q.name = gssd_dummy_clnt_dir[0].name;
1317 q.len = strlen(gssd_dummy_clnt_dir[0].name);
1318 clnt_dentry = d_hash_and_lookup(gssd_dentry, &q);
1319 if (!clnt_dentry) {
1320 pipe_dentry = ERR_PTR(-ENOENT);
1321 goto out;
1322 }
1323
1324 ret = rpc_populate(clnt_dentry, gssd_dummy_info_file, 0, 1, NULL);
1325 if (ret) {
1326 __rpc_depopulate(gssd_dentry, gssd_dummy_clnt_dir, 0, 1);
1327 pipe_dentry = ERR_PTR(ret);
1328 goto out;
1329 }
1330
1331 pipe_dentry = rpc_mkpipe_dentry(clnt_dentry, "gssd", NULL, pipe_data);
1332 if (IS_ERR(pipe_dentry)) {
1333 __rpc_depopulate(clnt_dentry, gssd_dummy_info_file, 0, 1);
1334 __rpc_depopulate(gssd_dentry, gssd_dummy_clnt_dir, 0, 1);
1335 }
1336out:
1337 dput(clnt_dentry);
1338 dput(gssd_dentry);
1339 return pipe_dentry;
1340}
1341
1342static void
1343rpc_gssd_dummy_depopulate(struct dentry *pipe_dentry)
1344{
1345 struct dentry *clnt_dir = pipe_dentry->d_parent;
1346 struct dentry *gssd_dir = clnt_dir->d_parent;
1347
1348 dget(pipe_dentry);
1349 __rpc_rmpipe(d_inode(clnt_dir), pipe_dentry);
1350 __rpc_depopulate(clnt_dir, gssd_dummy_info_file, 0, 1);
1351 __rpc_depopulate(gssd_dir, gssd_dummy_clnt_dir, 0, 1);
1352 dput(pipe_dentry);
1353}
1354
1355static int
1356rpc_fill_super(struct super_block *sb, struct fs_context *fc)
1357{
1358 struct inode *inode;
1359 struct dentry *root, *gssd_dentry;
1360 struct net *net = sb->s_fs_info;
1361 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1362 int err;
1363
1364 sb->s_blocksize = PAGE_SIZE;
1365 sb->s_blocksize_bits = PAGE_SHIFT;
1366 sb->s_magic = RPCAUTH_GSSMAGIC;
1367 sb->s_op = &s_ops;
1368 sb->s_d_op = &simple_dentry_operations;
1369 sb->s_time_gran = 1;
1370
1371 inode = rpc_get_inode(sb, S_IFDIR | 0555);
1372 sb->s_root = root = d_make_root(inode);
1373 if (!root)
1374 return -ENOMEM;
1375 if (rpc_populate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF, NULL))
1376 return -ENOMEM;
1377
1378 gssd_dentry = rpc_gssd_dummy_populate(root, sn->gssd_dummy);
1379 if (IS_ERR(gssd_dentry)) {
1380 __rpc_depopulate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF);
1381 return PTR_ERR(gssd_dentry);
1382 }
1383
1384 dprintk("RPC: sending pipefs MOUNT notification for net %x%s\n",
1385 net->ns.inum, NET_NAME(net));
1386 mutex_lock(&sn->pipefs_sb_lock);
1387 sn->pipefs_sb = sb;
1388 err = blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1389 RPC_PIPEFS_MOUNT,
1390 sb);
1391 if (err)
1392 goto err_depopulate;
1393 mutex_unlock(&sn->pipefs_sb_lock);
1394 return 0;
1395
1396err_depopulate:
1397 rpc_gssd_dummy_depopulate(gssd_dentry);
1398 blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1399 RPC_PIPEFS_UMOUNT,
1400 sb);
1401 sn->pipefs_sb = NULL;
1402 __rpc_depopulate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF);
1403 mutex_unlock(&sn->pipefs_sb_lock);
1404 return err;
1405}
1406
1407bool
1408gssd_running(struct net *net)
1409{
1410 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1411 struct rpc_pipe *pipe = sn->gssd_dummy;
1412
1413 return pipe->nreaders || pipe->nwriters;
1414}
1415EXPORT_SYMBOL_GPL(gssd_running);
1416
1417static int rpc_fs_get_tree(struct fs_context *fc)
1418{
1419 return get_tree_keyed(fc, rpc_fill_super, get_net(fc->net_ns));
1420}
1421
1422static void rpc_fs_free_fc(struct fs_context *fc)
1423{
1424 if (fc->s_fs_info)
1425 put_net(fc->s_fs_info);
1426}
1427
1428static const struct fs_context_operations rpc_fs_context_ops = {
1429 .free = rpc_fs_free_fc,
1430 .get_tree = rpc_fs_get_tree,
1431};
1432
1433static int rpc_init_fs_context(struct fs_context *fc)
1434{
1435 put_user_ns(fc->user_ns);
1436 fc->user_ns = get_user_ns(fc->net_ns->user_ns);
1437 fc->ops = &rpc_fs_context_ops;
1438 return 0;
1439}
1440
1441static void rpc_kill_sb(struct super_block *sb)
1442{
1443 struct net *net = sb->s_fs_info;
1444 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1445
1446 mutex_lock(&sn->pipefs_sb_lock);
1447 if (sn->pipefs_sb != sb) {
1448 mutex_unlock(&sn->pipefs_sb_lock);
1449 goto out;
1450 }
1451 sn->pipefs_sb = NULL;
1452 dprintk("RPC: sending pipefs UMOUNT notification for net %x%s\n",
1453 net->ns.inum, NET_NAME(net));
1454 blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1455 RPC_PIPEFS_UMOUNT,
1456 sb);
1457 mutex_unlock(&sn->pipefs_sb_lock);
1458out:
1459 kill_litter_super(sb);
1460 put_net(net);
1461}
1462
1463static struct file_system_type rpc_pipe_fs_type = {
1464 .owner = THIS_MODULE,
1465 .name = "rpc_pipefs",
1466 .init_fs_context = rpc_init_fs_context,
1467 .kill_sb = rpc_kill_sb,
1468};
1469MODULE_ALIAS_FS("rpc_pipefs");
1470MODULE_ALIAS("rpc_pipefs");
1471
1472static void
1473init_once(void *foo)
1474{
1475 struct rpc_inode *rpci = (struct rpc_inode *) foo;
1476
1477 inode_init_once(&rpci->vfs_inode);
1478 rpci->private = NULL;
1479 rpci->pipe = NULL;
1480 init_waitqueue_head(&rpci->waitq);
1481}
1482
1483int register_rpc_pipefs(void)
1484{
1485 int err;
1486
1487 rpc_inode_cachep = kmem_cache_create("rpc_inode_cache",
1488 sizeof(struct rpc_inode),
1489 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
1490 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
1491 init_once);
1492 if (!rpc_inode_cachep)
1493 return -ENOMEM;
1494 err = rpc_clients_notifier_register();
1495 if (err)
1496 goto err_notifier;
1497 err = register_filesystem(&rpc_pipe_fs_type);
1498 if (err)
1499 goto err_register;
1500 return 0;
1501
1502err_register:
1503 rpc_clients_notifier_unregister();
1504err_notifier:
1505 kmem_cache_destroy(rpc_inode_cachep);
1506 return err;
1507}
1508
1509void unregister_rpc_pipefs(void)
1510{
1511 rpc_clients_notifier_unregister();
1512 kmem_cache_destroy(rpc_inode_cachep);
1513 unregister_filesystem(&rpc_pipe_fs_type);
1514}
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/module.h>
12#include <linux/slab.h>
13#include <linux/string.h>
14#include <linux/pagemap.h>
15#include <linux/mount.h>
16#include <linux/namei.h>
17#include <linux/fsnotify.h>
18#include <linux/kernel.h>
19#include <linux/rcupdate.h>
20#include <linux/utsname.h>
21
22#include <asm/ioctls.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#include <linux/sunrpc/cache.h>
31#include <linux/nsproxy.h>
32#include <linux/notifier.h>
33
34#include "netns.h"
35#include "sunrpc.h"
36
37#define RPCDBG_FACILITY RPCDBG_DEBUG
38
39#define NET_NAME(net) ((net == &init_net) ? " (init_net)" : "")
40
41static struct file_system_type rpc_pipe_fs_type;
42static const struct rpc_pipe_ops gssd_dummy_pipe_ops;
43
44static struct kmem_cache *rpc_inode_cachep __read_mostly;
45
46#define RPC_UPCALL_TIMEOUT (30*HZ)
47
48static BLOCKING_NOTIFIER_HEAD(rpc_pipefs_notifier_list);
49
50int rpc_pipefs_notifier_register(struct notifier_block *nb)
51{
52 return blocking_notifier_chain_cond_register(&rpc_pipefs_notifier_list, nb);
53}
54EXPORT_SYMBOL_GPL(rpc_pipefs_notifier_register);
55
56void rpc_pipefs_notifier_unregister(struct notifier_block *nb)
57{
58 blocking_notifier_chain_unregister(&rpc_pipefs_notifier_list, nb);
59}
60EXPORT_SYMBOL_GPL(rpc_pipefs_notifier_unregister);
61
62static void rpc_purge_list(wait_queue_head_t *waitq, struct list_head *head,
63 void (*destroy_msg)(struct rpc_pipe_msg *), int err)
64{
65 struct rpc_pipe_msg *msg;
66
67 if (list_empty(head))
68 return;
69 do {
70 msg = list_entry(head->next, struct rpc_pipe_msg, list);
71 list_del_init(&msg->list);
72 msg->errno = err;
73 destroy_msg(msg);
74 } while (!list_empty(head));
75
76 if (waitq)
77 wake_up(waitq);
78}
79
80static void
81rpc_timeout_upcall_queue(struct work_struct *work)
82{
83 LIST_HEAD(free_list);
84 struct rpc_pipe *pipe =
85 container_of(work, struct rpc_pipe, queue_timeout.work);
86 void (*destroy_msg)(struct rpc_pipe_msg *);
87 struct dentry *dentry;
88
89 spin_lock(&pipe->lock);
90 destroy_msg = pipe->ops->destroy_msg;
91 if (pipe->nreaders == 0) {
92 list_splice_init(&pipe->pipe, &free_list);
93 pipe->pipelen = 0;
94 }
95 dentry = dget(pipe->dentry);
96 spin_unlock(&pipe->lock);
97 rpc_purge_list(dentry ? &RPC_I(dentry->d_inode)->waitq : NULL,
98 &free_list, destroy_msg, -ETIMEDOUT);
99 dput(dentry);
100}
101
102ssize_t rpc_pipe_generic_upcall(struct file *filp, struct rpc_pipe_msg *msg,
103 char __user *dst, size_t buflen)
104{
105 char *data = (char *)msg->data + msg->copied;
106 size_t mlen = min(msg->len - msg->copied, buflen);
107 unsigned long left;
108
109 left = copy_to_user(dst, data, mlen);
110 if (left == mlen) {
111 msg->errno = -EFAULT;
112 return -EFAULT;
113 }
114
115 mlen -= left;
116 msg->copied += mlen;
117 msg->errno = 0;
118 return mlen;
119}
120EXPORT_SYMBOL_GPL(rpc_pipe_generic_upcall);
121
122/**
123 * rpc_queue_upcall - queue an upcall message to userspace
124 * @pipe: upcall pipe on which to queue given message
125 * @msg: message to queue
126 *
127 * Call with an @inode created by rpc_mkpipe() to queue an upcall.
128 * A userspace process may then later read the upcall by performing a
129 * read on an open file for this inode. It is up to the caller to
130 * initialize the fields of @msg (other than @msg->list) appropriately.
131 */
132int
133rpc_queue_upcall(struct rpc_pipe *pipe, struct rpc_pipe_msg *msg)
134{
135 int res = -EPIPE;
136 struct dentry *dentry;
137
138 spin_lock(&pipe->lock);
139 if (pipe->nreaders) {
140 list_add_tail(&msg->list, &pipe->pipe);
141 pipe->pipelen += msg->len;
142 res = 0;
143 } else if (pipe->flags & RPC_PIPE_WAIT_FOR_OPEN) {
144 if (list_empty(&pipe->pipe))
145 queue_delayed_work(rpciod_workqueue,
146 &pipe->queue_timeout,
147 RPC_UPCALL_TIMEOUT);
148 list_add_tail(&msg->list, &pipe->pipe);
149 pipe->pipelen += msg->len;
150 res = 0;
151 }
152 dentry = dget(pipe->dentry);
153 spin_unlock(&pipe->lock);
154 if (dentry) {
155 wake_up(&RPC_I(dentry->d_inode)->waitq);
156 dput(dentry);
157 }
158 return res;
159}
160EXPORT_SYMBOL_GPL(rpc_queue_upcall);
161
162static inline void
163rpc_inode_setowner(struct inode *inode, void *private)
164{
165 RPC_I(inode)->private = private;
166}
167
168static void
169rpc_close_pipes(struct inode *inode)
170{
171 struct rpc_pipe *pipe = RPC_I(inode)->pipe;
172 int need_release;
173 LIST_HEAD(free_list);
174
175 mutex_lock(&inode->i_mutex);
176 spin_lock(&pipe->lock);
177 need_release = pipe->nreaders != 0 || pipe->nwriters != 0;
178 pipe->nreaders = 0;
179 list_splice_init(&pipe->in_upcall, &free_list);
180 list_splice_init(&pipe->pipe, &free_list);
181 pipe->pipelen = 0;
182 pipe->dentry = NULL;
183 spin_unlock(&pipe->lock);
184 rpc_purge_list(&RPC_I(inode)->waitq, &free_list, pipe->ops->destroy_msg, -EPIPE);
185 pipe->nwriters = 0;
186 if (need_release && pipe->ops->release_pipe)
187 pipe->ops->release_pipe(inode);
188 cancel_delayed_work_sync(&pipe->queue_timeout);
189 rpc_inode_setowner(inode, NULL);
190 RPC_I(inode)->pipe = NULL;
191 mutex_unlock(&inode->i_mutex);
192}
193
194static struct inode *
195rpc_alloc_inode(struct super_block *sb)
196{
197 struct rpc_inode *rpci;
198 rpci = (struct rpc_inode *)kmem_cache_alloc(rpc_inode_cachep, GFP_KERNEL);
199 if (!rpci)
200 return NULL;
201 return &rpci->vfs_inode;
202}
203
204static void
205rpc_i_callback(struct rcu_head *head)
206{
207 struct inode *inode = container_of(head, struct inode, i_rcu);
208 kmem_cache_free(rpc_inode_cachep, RPC_I(inode));
209}
210
211static void
212rpc_destroy_inode(struct inode *inode)
213{
214 call_rcu(&inode->i_rcu, rpc_i_callback);
215}
216
217static int
218rpc_pipe_open(struct inode *inode, struct file *filp)
219{
220 struct rpc_pipe *pipe;
221 int first_open;
222 int res = -ENXIO;
223
224 mutex_lock(&inode->i_mutex);
225 pipe = RPC_I(inode)->pipe;
226 if (pipe == NULL)
227 goto out;
228 first_open = pipe->nreaders == 0 && pipe->nwriters == 0;
229 if (first_open && pipe->ops->open_pipe) {
230 res = pipe->ops->open_pipe(inode);
231 if (res)
232 goto out;
233 }
234 if (filp->f_mode & FMODE_READ)
235 pipe->nreaders++;
236 if (filp->f_mode & FMODE_WRITE)
237 pipe->nwriters++;
238 res = 0;
239out:
240 mutex_unlock(&inode->i_mutex);
241 return res;
242}
243
244static int
245rpc_pipe_release(struct inode *inode, struct file *filp)
246{
247 struct rpc_pipe *pipe;
248 struct rpc_pipe_msg *msg;
249 int last_close;
250
251 mutex_lock(&inode->i_mutex);
252 pipe = RPC_I(inode)->pipe;
253 if (pipe == NULL)
254 goto out;
255 msg = filp->private_data;
256 if (msg != NULL) {
257 spin_lock(&pipe->lock);
258 msg->errno = -EAGAIN;
259 list_del_init(&msg->list);
260 spin_unlock(&pipe->lock);
261 pipe->ops->destroy_msg(msg);
262 }
263 if (filp->f_mode & FMODE_WRITE)
264 pipe->nwriters --;
265 if (filp->f_mode & FMODE_READ) {
266 pipe->nreaders --;
267 if (pipe->nreaders == 0) {
268 LIST_HEAD(free_list);
269 spin_lock(&pipe->lock);
270 list_splice_init(&pipe->pipe, &free_list);
271 pipe->pipelen = 0;
272 spin_unlock(&pipe->lock);
273 rpc_purge_list(&RPC_I(inode)->waitq, &free_list,
274 pipe->ops->destroy_msg, -EAGAIN);
275 }
276 }
277 last_close = pipe->nwriters == 0 && pipe->nreaders == 0;
278 if (last_close && pipe->ops->release_pipe)
279 pipe->ops->release_pipe(inode);
280out:
281 mutex_unlock(&inode->i_mutex);
282 return 0;
283}
284
285static ssize_t
286rpc_pipe_read(struct file *filp, char __user *buf, size_t len, loff_t *offset)
287{
288 struct inode *inode = file_inode(filp);
289 struct rpc_pipe *pipe;
290 struct rpc_pipe_msg *msg;
291 int res = 0;
292
293 mutex_lock(&inode->i_mutex);
294 pipe = RPC_I(inode)->pipe;
295 if (pipe == NULL) {
296 res = -EPIPE;
297 goto out_unlock;
298 }
299 msg = filp->private_data;
300 if (msg == NULL) {
301 spin_lock(&pipe->lock);
302 if (!list_empty(&pipe->pipe)) {
303 msg = list_entry(pipe->pipe.next,
304 struct rpc_pipe_msg,
305 list);
306 list_move(&msg->list, &pipe->in_upcall);
307 pipe->pipelen -= msg->len;
308 filp->private_data = msg;
309 msg->copied = 0;
310 }
311 spin_unlock(&pipe->lock);
312 if (msg == NULL)
313 goto out_unlock;
314 }
315 /* NOTE: it is up to the callback to update msg->copied */
316 res = pipe->ops->upcall(filp, msg, buf, len);
317 if (res < 0 || msg->len == msg->copied) {
318 filp->private_data = NULL;
319 spin_lock(&pipe->lock);
320 list_del_init(&msg->list);
321 spin_unlock(&pipe->lock);
322 pipe->ops->destroy_msg(msg);
323 }
324out_unlock:
325 mutex_unlock(&inode->i_mutex);
326 return res;
327}
328
329static ssize_t
330rpc_pipe_write(struct file *filp, const char __user *buf, size_t len, loff_t *offset)
331{
332 struct inode *inode = file_inode(filp);
333 int res;
334
335 mutex_lock(&inode->i_mutex);
336 res = -EPIPE;
337 if (RPC_I(inode)->pipe != NULL)
338 res = RPC_I(inode)->pipe->ops->downcall(filp, buf, len);
339 mutex_unlock(&inode->i_mutex);
340 return res;
341}
342
343static unsigned int
344rpc_pipe_poll(struct file *filp, struct poll_table_struct *wait)
345{
346 struct inode *inode = file_inode(filp);
347 struct rpc_inode *rpci = RPC_I(inode);
348 unsigned int mask = POLLOUT | POLLWRNORM;
349
350 poll_wait(filp, &rpci->waitq, wait);
351
352 mutex_lock(&inode->i_mutex);
353 if (rpci->pipe == NULL)
354 mask |= POLLERR | POLLHUP;
355 else if (filp->private_data || !list_empty(&rpci->pipe->pipe))
356 mask |= POLLIN | POLLRDNORM;
357 mutex_unlock(&inode->i_mutex);
358 return mask;
359}
360
361static long
362rpc_pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
363{
364 struct inode *inode = file_inode(filp);
365 struct rpc_pipe *pipe;
366 int len;
367
368 switch (cmd) {
369 case FIONREAD:
370 mutex_lock(&inode->i_mutex);
371 pipe = RPC_I(inode)->pipe;
372 if (pipe == NULL) {
373 mutex_unlock(&inode->i_mutex);
374 return -EPIPE;
375 }
376 spin_lock(&pipe->lock);
377 len = pipe->pipelen;
378 if (filp->private_data) {
379 struct rpc_pipe_msg *msg;
380 msg = filp->private_data;
381 len += msg->len - msg->copied;
382 }
383 spin_unlock(&pipe->lock);
384 mutex_unlock(&inode->i_mutex);
385 return put_user(len, (int __user *)arg);
386 default:
387 return -EINVAL;
388 }
389}
390
391static const struct file_operations rpc_pipe_fops = {
392 .owner = THIS_MODULE,
393 .llseek = no_llseek,
394 .read = rpc_pipe_read,
395 .write = rpc_pipe_write,
396 .poll = rpc_pipe_poll,
397 .unlocked_ioctl = rpc_pipe_ioctl,
398 .open = rpc_pipe_open,
399 .release = rpc_pipe_release,
400};
401
402static int
403rpc_show_info(struct seq_file *m, void *v)
404{
405 struct rpc_clnt *clnt = m->private;
406
407 rcu_read_lock();
408 seq_printf(m, "RPC server: %s\n",
409 rcu_dereference(clnt->cl_xprt)->servername);
410 seq_printf(m, "service: %s (%d) version %d\n", clnt->cl_program->name,
411 clnt->cl_prog, clnt->cl_vers);
412 seq_printf(m, "address: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR));
413 seq_printf(m, "protocol: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_PROTO));
414 seq_printf(m, "port: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_PORT));
415 rcu_read_unlock();
416 return 0;
417}
418
419static int
420rpc_info_open(struct inode *inode, struct file *file)
421{
422 struct rpc_clnt *clnt = NULL;
423 int ret = single_open(file, rpc_show_info, NULL);
424
425 if (!ret) {
426 struct seq_file *m = file->private_data;
427
428 spin_lock(&file->f_path.dentry->d_lock);
429 if (!d_unhashed(file->f_path.dentry))
430 clnt = RPC_I(inode)->private;
431 if (clnt != NULL && atomic_inc_not_zero(&clnt->cl_count)) {
432 spin_unlock(&file->f_path.dentry->d_lock);
433 m->private = clnt;
434 } else {
435 spin_unlock(&file->f_path.dentry->d_lock);
436 single_release(inode, file);
437 ret = -EINVAL;
438 }
439 }
440 return ret;
441}
442
443static int
444rpc_info_release(struct inode *inode, struct file *file)
445{
446 struct seq_file *m = file->private_data;
447 struct rpc_clnt *clnt = (struct rpc_clnt *)m->private;
448
449 if (clnt)
450 rpc_release_client(clnt);
451 return single_release(inode, file);
452}
453
454static const struct file_operations rpc_info_operations = {
455 .owner = THIS_MODULE,
456 .open = rpc_info_open,
457 .read = seq_read,
458 .llseek = seq_lseek,
459 .release = rpc_info_release,
460};
461
462
463/*
464 * Description of fs contents.
465 */
466struct rpc_filelist {
467 const char *name;
468 const struct file_operations *i_fop;
469 umode_t mode;
470};
471
472static struct inode *
473rpc_get_inode(struct super_block *sb, umode_t mode)
474{
475 struct inode *inode = new_inode(sb);
476 if (!inode)
477 return NULL;
478 inode->i_ino = get_next_ino();
479 inode->i_mode = mode;
480 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
481 switch (mode & S_IFMT) {
482 case S_IFDIR:
483 inode->i_fop = &simple_dir_operations;
484 inode->i_op = &simple_dir_inode_operations;
485 inc_nlink(inode);
486 default:
487 break;
488 }
489 return inode;
490}
491
492static int __rpc_create_common(struct inode *dir, struct dentry *dentry,
493 umode_t mode,
494 const struct file_operations *i_fop,
495 void *private)
496{
497 struct inode *inode;
498
499 d_drop(dentry);
500 inode = rpc_get_inode(dir->i_sb, mode);
501 if (!inode)
502 goto out_err;
503 inode->i_ino = iunique(dir->i_sb, 100);
504 if (i_fop)
505 inode->i_fop = i_fop;
506 if (private)
507 rpc_inode_setowner(inode, private);
508 d_add(dentry, inode);
509 return 0;
510out_err:
511 printk(KERN_WARNING "%s: %s failed to allocate inode for dentry %pd\n",
512 __FILE__, __func__, dentry);
513 dput(dentry);
514 return -ENOMEM;
515}
516
517static int __rpc_create(struct inode *dir, struct dentry *dentry,
518 umode_t mode,
519 const struct file_operations *i_fop,
520 void *private)
521{
522 int err;
523
524 err = __rpc_create_common(dir, dentry, S_IFREG | mode, i_fop, private);
525 if (err)
526 return err;
527 fsnotify_create(dir, dentry);
528 return 0;
529}
530
531static int __rpc_mkdir(struct inode *dir, struct dentry *dentry,
532 umode_t mode,
533 const struct file_operations *i_fop,
534 void *private)
535{
536 int err;
537
538 err = __rpc_create_common(dir, dentry, S_IFDIR | mode, i_fop, private);
539 if (err)
540 return err;
541 inc_nlink(dir);
542 fsnotify_mkdir(dir, dentry);
543 return 0;
544}
545
546static void
547init_pipe(struct rpc_pipe *pipe)
548{
549 pipe->nreaders = 0;
550 pipe->nwriters = 0;
551 INIT_LIST_HEAD(&pipe->in_upcall);
552 INIT_LIST_HEAD(&pipe->in_downcall);
553 INIT_LIST_HEAD(&pipe->pipe);
554 pipe->pipelen = 0;
555 INIT_DELAYED_WORK(&pipe->queue_timeout,
556 rpc_timeout_upcall_queue);
557 pipe->ops = NULL;
558 spin_lock_init(&pipe->lock);
559 pipe->dentry = NULL;
560}
561
562void rpc_destroy_pipe_data(struct rpc_pipe *pipe)
563{
564 kfree(pipe);
565}
566EXPORT_SYMBOL_GPL(rpc_destroy_pipe_data);
567
568struct rpc_pipe *rpc_mkpipe_data(const struct rpc_pipe_ops *ops, int flags)
569{
570 struct rpc_pipe *pipe;
571
572 pipe = kzalloc(sizeof(struct rpc_pipe), GFP_KERNEL);
573 if (!pipe)
574 return ERR_PTR(-ENOMEM);
575 init_pipe(pipe);
576 pipe->ops = ops;
577 pipe->flags = flags;
578 return pipe;
579}
580EXPORT_SYMBOL_GPL(rpc_mkpipe_data);
581
582static int __rpc_mkpipe_dentry(struct inode *dir, struct dentry *dentry,
583 umode_t mode,
584 const struct file_operations *i_fop,
585 void *private,
586 struct rpc_pipe *pipe)
587{
588 struct rpc_inode *rpci;
589 int err;
590
591 err = __rpc_create_common(dir, dentry, S_IFIFO | mode, i_fop, private);
592 if (err)
593 return err;
594 rpci = RPC_I(dentry->d_inode);
595 rpci->private = private;
596 rpci->pipe = pipe;
597 fsnotify_create(dir, dentry);
598 return 0;
599}
600
601static int __rpc_rmdir(struct inode *dir, struct dentry *dentry)
602{
603 int ret;
604
605 dget(dentry);
606 ret = simple_rmdir(dir, dentry);
607 d_delete(dentry);
608 dput(dentry);
609 return ret;
610}
611
612int rpc_rmdir(struct dentry *dentry)
613{
614 struct dentry *parent;
615 struct inode *dir;
616 int error;
617
618 parent = dget_parent(dentry);
619 dir = parent->d_inode;
620 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
621 error = __rpc_rmdir(dir, dentry);
622 mutex_unlock(&dir->i_mutex);
623 dput(parent);
624 return error;
625}
626EXPORT_SYMBOL_GPL(rpc_rmdir);
627
628static int __rpc_unlink(struct inode *dir, struct dentry *dentry)
629{
630 int ret;
631
632 dget(dentry);
633 ret = simple_unlink(dir, dentry);
634 d_delete(dentry);
635 dput(dentry);
636 return ret;
637}
638
639static int __rpc_rmpipe(struct inode *dir, struct dentry *dentry)
640{
641 struct inode *inode = dentry->d_inode;
642
643 rpc_close_pipes(inode);
644 return __rpc_unlink(dir, dentry);
645}
646
647static struct dentry *__rpc_lookup_create_exclusive(struct dentry *parent,
648 const char *name)
649{
650 struct qstr q = QSTR_INIT(name, strlen(name));
651 struct dentry *dentry = d_hash_and_lookup(parent, &q);
652 if (!dentry) {
653 dentry = d_alloc(parent, &q);
654 if (!dentry)
655 return ERR_PTR(-ENOMEM);
656 }
657 if (dentry->d_inode == NULL)
658 return dentry;
659 dput(dentry);
660 return ERR_PTR(-EEXIST);
661}
662
663/*
664 * FIXME: This probably has races.
665 */
666static void __rpc_depopulate(struct dentry *parent,
667 const struct rpc_filelist *files,
668 int start, int eof)
669{
670 struct inode *dir = parent->d_inode;
671 struct dentry *dentry;
672 struct qstr name;
673 int i;
674
675 for (i = start; i < eof; i++) {
676 name.name = files[i].name;
677 name.len = strlen(files[i].name);
678 dentry = d_hash_and_lookup(parent, &name);
679
680 if (dentry == NULL)
681 continue;
682 if (dentry->d_inode == NULL)
683 goto next;
684 switch (dentry->d_inode->i_mode & S_IFMT) {
685 default:
686 BUG();
687 case S_IFREG:
688 __rpc_unlink(dir, dentry);
689 break;
690 case S_IFDIR:
691 __rpc_rmdir(dir, dentry);
692 }
693next:
694 dput(dentry);
695 }
696}
697
698static void rpc_depopulate(struct dentry *parent,
699 const struct rpc_filelist *files,
700 int start, int eof)
701{
702 struct inode *dir = parent->d_inode;
703
704 mutex_lock_nested(&dir->i_mutex, I_MUTEX_CHILD);
705 __rpc_depopulate(parent, files, start, eof);
706 mutex_unlock(&dir->i_mutex);
707}
708
709static int rpc_populate(struct dentry *parent,
710 const struct rpc_filelist *files,
711 int start, int eof,
712 void *private)
713{
714 struct inode *dir = parent->d_inode;
715 struct dentry *dentry;
716 int i, err;
717
718 mutex_lock(&dir->i_mutex);
719 for (i = start; i < eof; i++) {
720 dentry = __rpc_lookup_create_exclusive(parent, files[i].name);
721 err = PTR_ERR(dentry);
722 if (IS_ERR(dentry))
723 goto out_bad;
724 switch (files[i].mode & S_IFMT) {
725 default:
726 BUG();
727 case S_IFREG:
728 err = __rpc_create(dir, dentry,
729 files[i].mode,
730 files[i].i_fop,
731 private);
732 break;
733 case S_IFDIR:
734 err = __rpc_mkdir(dir, dentry,
735 files[i].mode,
736 NULL,
737 private);
738 }
739 if (err != 0)
740 goto out_bad;
741 }
742 mutex_unlock(&dir->i_mutex);
743 return 0;
744out_bad:
745 __rpc_depopulate(parent, files, start, eof);
746 mutex_unlock(&dir->i_mutex);
747 printk(KERN_WARNING "%s: %s failed to populate directory %pd\n",
748 __FILE__, __func__, parent);
749 return err;
750}
751
752static struct dentry *rpc_mkdir_populate(struct dentry *parent,
753 const char *name, umode_t mode, void *private,
754 int (*populate)(struct dentry *, void *), void *args_populate)
755{
756 struct dentry *dentry;
757 struct inode *dir = parent->d_inode;
758 int error;
759
760 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
761 dentry = __rpc_lookup_create_exclusive(parent, name);
762 if (IS_ERR(dentry))
763 goto out;
764 error = __rpc_mkdir(dir, dentry, mode, NULL, private);
765 if (error != 0)
766 goto out_err;
767 if (populate != NULL) {
768 error = populate(dentry, args_populate);
769 if (error)
770 goto err_rmdir;
771 }
772out:
773 mutex_unlock(&dir->i_mutex);
774 return dentry;
775err_rmdir:
776 __rpc_rmdir(dir, dentry);
777out_err:
778 dentry = ERR_PTR(error);
779 goto out;
780}
781
782static int rpc_rmdir_depopulate(struct dentry *dentry,
783 void (*depopulate)(struct dentry *))
784{
785 struct dentry *parent;
786 struct inode *dir;
787 int error;
788
789 parent = dget_parent(dentry);
790 dir = parent->d_inode;
791 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
792 if (depopulate != NULL)
793 depopulate(dentry);
794 error = __rpc_rmdir(dir, dentry);
795 mutex_unlock(&dir->i_mutex);
796 dput(parent);
797 return error;
798}
799
800/**
801 * rpc_mkpipe - make an rpc_pipefs file for kernel<->userspace communication
802 * @parent: dentry of directory to create new "pipe" in
803 * @name: name of pipe
804 * @private: private data to associate with the pipe, for the caller's use
805 * @pipe: &rpc_pipe containing input parameters
806 *
807 * Data is made available for userspace to read by calls to
808 * rpc_queue_upcall(). The actual reads will result in calls to
809 * @ops->upcall, which will be called with the file pointer,
810 * message, and userspace buffer to copy to.
811 *
812 * Writes can come at any time, and do not necessarily have to be
813 * responses to upcalls. They will result in calls to @msg->downcall.
814 *
815 * The @private argument passed here will be available to all these methods
816 * from the file pointer, via RPC_I(file_inode(file))->private.
817 */
818struct dentry *rpc_mkpipe_dentry(struct dentry *parent, const char *name,
819 void *private, struct rpc_pipe *pipe)
820{
821 struct dentry *dentry;
822 struct inode *dir = parent->d_inode;
823 umode_t umode = S_IFIFO | S_IRUSR | S_IWUSR;
824 int err;
825
826 if (pipe->ops->upcall == NULL)
827 umode &= ~S_IRUGO;
828 if (pipe->ops->downcall == NULL)
829 umode &= ~S_IWUGO;
830
831 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
832 dentry = __rpc_lookup_create_exclusive(parent, name);
833 if (IS_ERR(dentry))
834 goto out;
835 err = __rpc_mkpipe_dentry(dir, dentry, umode, &rpc_pipe_fops,
836 private, pipe);
837 if (err)
838 goto out_err;
839out:
840 mutex_unlock(&dir->i_mutex);
841 return dentry;
842out_err:
843 dentry = ERR_PTR(err);
844 printk(KERN_WARNING "%s: %s() failed to create pipe %pd/%s (errno = %d)\n",
845 __FILE__, __func__, parent, name,
846 err);
847 goto out;
848}
849EXPORT_SYMBOL_GPL(rpc_mkpipe_dentry);
850
851/**
852 * rpc_unlink - remove a pipe
853 * @dentry: dentry for the pipe, as returned from rpc_mkpipe
854 *
855 * After this call, lookups will no longer find the pipe, and any
856 * attempts to read or write using preexisting opens of the pipe will
857 * return -EPIPE.
858 */
859int
860rpc_unlink(struct dentry *dentry)
861{
862 struct dentry *parent;
863 struct inode *dir;
864 int error = 0;
865
866 parent = dget_parent(dentry);
867 dir = parent->d_inode;
868 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
869 error = __rpc_rmpipe(dir, dentry);
870 mutex_unlock(&dir->i_mutex);
871 dput(parent);
872 return error;
873}
874EXPORT_SYMBOL_GPL(rpc_unlink);
875
876/**
877 * rpc_init_pipe_dir_head - initialise a struct rpc_pipe_dir_head
878 * @pdh: pointer to struct rpc_pipe_dir_head
879 */
880void rpc_init_pipe_dir_head(struct rpc_pipe_dir_head *pdh)
881{
882 INIT_LIST_HEAD(&pdh->pdh_entries);
883 pdh->pdh_dentry = NULL;
884}
885EXPORT_SYMBOL_GPL(rpc_init_pipe_dir_head);
886
887/**
888 * rpc_init_pipe_dir_object - initialise a struct rpc_pipe_dir_object
889 * @pdo: pointer to struct rpc_pipe_dir_object
890 * @pdo_ops: pointer to const struct rpc_pipe_dir_object_ops
891 * @pdo_data: pointer to caller-defined data
892 */
893void rpc_init_pipe_dir_object(struct rpc_pipe_dir_object *pdo,
894 const struct rpc_pipe_dir_object_ops *pdo_ops,
895 void *pdo_data)
896{
897 INIT_LIST_HEAD(&pdo->pdo_head);
898 pdo->pdo_ops = pdo_ops;
899 pdo->pdo_data = pdo_data;
900}
901EXPORT_SYMBOL_GPL(rpc_init_pipe_dir_object);
902
903static int
904rpc_add_pipe_dir_object_locked(struct net *net,
905 struct rpc_pipe_dir_head *pdh,
906 struct rpc_pipe_dir_object *pdo)
907{
908 int ret = 0;
909
910 if (pdh->pdh_dentry)
911 ret = pdo->pdo_ops->create(pdh->pdh_dentry, pdo);
912 if (ret == 0)
913 list_add_tail(&pdo->pdo_head, &pdh->pdh_entries);
914 return ret;
915}
916
917static void
918rpc_remove_pipe_dir_object_locked(struct net *net,
919 struct rpc_pipe_dir_head *pdh,
920 struct rpc_pipe_dir_object *pdo)
921{
922 if (pdh->pdh_dentry)
923 pdo->pdo_ops->destroy(pdh->pdh_dentry, pdo);
924 list_del_init(&pdo->pdo_head);
925}
926
927/**
928 * rpc_add_pipe_dir_object - associate a rpc_pipe_dir_object to a directory
929 * @net: pointer to struct net
930 * @pdh: pointer to struct rpc_pipe_dir_head
931 * @pdo: pointer to struct rpc_pipe_dir_object
932 *
933 */
934int
935rpc_add_pipe_dir_object(struct net *net,
936 struct rpc_pipe_dir_head *pdh,
937 struct rpc_pipe_dir_object *pdo)
938{
939 int ret = 0;
940
941 if (list_empty(&pdo->pdo_head)) {
942 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
943
944 mutex_lock(&sn->pipefs_sb_lock);
945 ret = rpc_add_pipe_dir_object_locked(net, pdh, pdo);
946 mutex_unlock(&sn->pipefs_sb_lock);
947 }
948 return ret;
949}
950EXPORT_SYMBOL_GPL(rpc_add_pipe_dir_object);
951
952/**
953 * rpc_remove_pipe_dir_object - remove a rpc_pipe_dir_object from a directory
954 * @net: pointer to struct net
955 * @pdh: pointer to struct rpc_pipe_dir_head
956 * @pdo: pointer to struct rpc_pipe_dir_object
957 *
958 */
959void
960rpc_remove_pipe_dir_object(struct net *net,
961 struct rpc_pipe_dir_head *pdh,
962 struct rpc_pipe_dir_object *pdo)
963{
964 if (!list_empty(&pdo->pdo_head)) {
965 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
966
967 mutex_lock(&sn->pipefs_sb_lock);
968 rpc_remove_pipe_dir_object_locked(net, pdh, pdo);
969 mutex_unlock(&sn->pipefs_sb_lock);
970 }
971}
972EXPORT_SYMBOL_GPL(rpc_remove_pipe_dir_object);
973
974/**
975 * rpc_find_or_alloc_pipe_dir_object
976 * @net: pointer to struct net
977 * @pdh: pointer to struct rpc_pipe_dir_head
978 * @match: match struct rpc_pipe_dir_object to data
979 * @alloc: allocate a new struct rpc_pipe_dir_object
980 * @data: user defined data for match() and alloc()
981 *
982 */
983struct rpc_pipe_dir_object *
984rpc_find_or_alloc_pipe_dir_object(struct net *net,
985 struct rpc_pipe_dir_head *pdh,
986 int (*match)(struct rpc_pipe_dir_object *, void *),
987 struct rpc_pipe_dir_object *(*alloc)(void *),
988 void *data)
989{
990 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
991 struct rpc_pipe_dir_object *pdo;
992
993 mutex_lock(&sn->pipefs_sb_lock);
994 list_for_each_entry(pdo, &pdh->pdh_entries, pdo_head) {
995 if (!match(pdo, data))
996 continue;
997 goto out;
998 }
999 pdo = alloc(data);
1000 if (!pdo)
1001 goto out;
1002 rpc_add_pipe_dir_object_locked(net, pdh, pdo);
1003out:
1004 mutex_unlock(&sn->pipefs_sb_lock);
1005 return pdo;
1006}
1007EXPORT_SYMBOL_GPL(rpc_find_or_alloc_pipe_dir_object);
1008
1009static void
1010rpc_create_pipe_dir_objects(struct rpc_pipe_dir_head *pdh)
1011{
1012 struct rpc_pipe_dir_object *pdo;
1013 struct dentry *dir = pdh->pdh_dentry;
1014
1015 list_for_each_entry(pdo, &pdh->pdh_entries, pdo_head)
1016 pdo->pdo_ops->create(dir, pdo);
1017}
1018
1019static void
1020rpc_destroy_pipe_dir_objects(struct rpc_pipe_dir_head *pdh)
1021{
1022 struct rpc_pipe_dir_object *pdo;
1023 struct dentry *dir = pdh->pdh_dentry;
1024
1025 list_for_each_entry(pdo, &pdh->pdh_entries, pdo_head)
1026 pdo->pdo_ops->destroy(dir, pdo);
1027}
1028
1029enum {
1030 RPCAUTH_info,
1031 RPCAUTH_EOF
1032};
1033
1034static const struct rpc_filelist authfiles[] = {
1035 [RPCAUTH_info] = {
1036 .name = "info",
1037 .i_fop = &rpc_info_operations,
1038 .mode = S_IFREG | S_IRUSR,
1039 },
1040};
1041
1042static int rpc_clntdir_populate(struct dentry *dentry, void *private)
1043{
1044 return rpc_populate(dentry,
1045 authfiles, RPCAUTH_info, RPCAUTH_EOF,
1046 private);
1047}
1048
1049static void rpc_clntdir_depopulate(struct dentry *dentry)
1050{
1051 rpc_depopulate(dentry, authfiles, RPCAUTH_info, RPCAUTH_EOF);
1052}
1053
1054/**
1055 * rpc_create_client_dir - Create a new rpc_client directory in rpc_pipefs
1056 * @dentry: the parent of new directory
1057 * @name: the name of new directory
1058 * @rpc_client: rpc client to associate with this directory
1059 *
1060 * This creates a directory at the given @path associated with
1061 * @rpc_clnt, which will contain a file named "info" with some basic
1062 * information about the client, together with any "pipes" that may
1063 * later be created using rpc_mkpipe().
1064 */
1065struct dentry *rpc_create_client_dir(struct dentry *dentry,
1066 const char *name,
1067 struct rpc_clnt *rpc_client)
1068{
1069 struct dentry *ret;
1070
1071 ret = rpc_mkdir_populate(dentry, name, S_IRUGO | S_IXUGO, NULL,
1072 rpc_clntdir_populate, rpc_client);
1073 if (!IS_ERR(ret)) {
1074 rpc_client->cl_pipedir_objects.pdh_dentry = ret;
1075 rpc_create_pipe_dir_objects(&rpc_client->cl_pipedir_objects);
1076 }
1077 return ret;
1078}
1079
1080/**
1081 * rpc_remove_client_dir - Remove a directory created with rpc_create_client_dir()
1082 * @rpc_client: rpc_client for the pipe
1083 */
1084int rpc_remove_client_dir(struct rpc_clnt *rpc_client)
1085{
1086 struct dentry *dentry = rpc_client->cl_pipedir_objects.pdh_dentry;
1087
1088 if (dentry == NULL)
1089 return 0;
1090 rpc_destroy_pipe_dir_objects(&rpc_client->cl_pipedir_objects);
1091 rpc_client->cl_pipedir_objects.pdh_dentry = NULL;
1092 return rpc_rmdir_depopulate(dentry, rpc_clntdir_depopulate);
1093}
1094
1095static const struct rpc_filelist cache_pipefs_files[3] = {
1096 [0] = {
1097 .name = "channel",
1098 .i_fop = &cache_file_operations_pipefs,
1099 .mode = S_IFREG|S_IRUSR|S_IWUSR,
1100 },
1101 [1] = {
1102 .name = "content",
1103 .i_fop = &content_file_operations_pipefs,
1104 .mode = S_IFREG|S_IRUSR,
1105 },
1106 [2] = {
1107 .name = "flush",
1108 .i_fop = &cache_flush_operations_pipefs,
1109 .mode = S_IFREG|S_IRUSR|S_IWUSR,
1110 },
1111};
1112
1113static int rpc_cachedir_populate(struct dentry *dentry, void *private)
1114{
1115 return rpc_populate(dentry,
1116 cache_pipefs_files, 0, 3,
1117 private);
1118}
1119
1120static void rpc_cachedir_depopulate(struct dentry *dentry)
1121{
1122 rpc_depopulate(dentry, cache_pipefs_files, 0, 3);
1123}
1124
1125struct dentry *rpc_create_cache_dir(struct dentry *parent, const char *name,
1126 umode_t umode, struct cache_detail *cd)
1127{
1128 return rpc_mkdir_populate(parent, name, umode, NULL,
1129 rpc_cachedir_populate, cd);
1130}
1131
1132void rpc_remove_cache_dir(struct dentry *dentry)
1133{
1134 rpc_rmdir_depopulate(dentry, rpc_cachedir_depopulate);
1135}
1136
1137/*
1138 * populate the filesystem
1139 */
1140static const struct super_operations s_ops = {
1141 .alloc_inode = rpc_alloc_inode,
1142 .destroy_inode = rpc_destroy_inode,
1143 .statfs = simple_statfs,
1144};
1145
1146#define RPCAUTH_GSSMAGIC 0x67596969
1147
1148/*
1149 * We have a single directory with 1 node in it.
1150 */
1151enum {
1152 RPCAUTH_lockd,
1153 RPCAUTH_mount,
1154 RPCAUTH_nfs,
1155 RPCAUTH_portmap,
1156 RPCAUTH_statd,
1157 RPCAUTH_nfsd4_cb,
1158 RPCAUTH_cache,
1159 RPCAUTH_nfsd,
1160 RPCAUTH_gssd,
1161 RPCAUTH_RootEOF
1162};
1163
1164static const struct rpc_filelist files[] = {
1165 [RPCAUTH_lockd] = {
1166 .name = "lockd",
1167 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1168 },
1169 [RPCAUTH_mount] = {
1170 .name = "mount",
1171 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1172 },
1173 [RPCAUTH_nfs] = {
1174 .name = "nfs",
1175 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1176 },
1177 [RPCAUTH_portmap] = {
1178 .name = "portmap",
1179 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1180 },
1181 [RPCAUTH_statd] = {
1182 .name = "statd",
1183 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1184 },
1185 [RPCAUTH_nfsd4_cb] = {
1186 .name = "nfsd4_cb",
1187 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1188 },
1189 [RPCAUTH_cache] = {
1190 .name = "cache",
1191 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1192 },
1193 [RPCAUTH_nfsd] = {
1194 .name = "nfsd",
1195 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1196 },
1197 [RPCAUTH_gssd] = {
1198 .name = "gssd",
1199 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1200 },
1201};
1202
1203/*
1204 * This call can be used only in RPC pipefs mount notification hooks.
1205 */
1206struct dentry *rpc_d_lookup_sb(const struct super_block *sb,
1207 const unsigned char *dir_name)
1208{
1209 struct qstr dir = QSTR_INIT(dir_name, strlen(dir_name));
1210 return d_hash_and_lookup(sb->s_root, &dir);
1211}
1212EXPORT_SYMBOL_GPL(rpc_d_lookup_sb);
1213
1214int rpc_pipefs_init_net(struct net *net)
1215{
1216 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1217
1218 sn->gssd_dummy = rpc_mkpipe_data(&gssd_dummy_pipe_ops, 0);
1219 if (IS_ERR(sn->gssd_dummy))
1220 return PTR_ERR(sn->gssd_dummy);
1221
1222 mutex_init(&sn->pipefs_sb_lock);
1223 sn->pipe_version = -1;
1224 return 0;
1225}
1226
1227void rpc_pipefs_exit_net(struct net *net)
1228{
1229 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1230
1231 rpc_destroy_pipe_data(sn->gssd_dummy);
1232}
1233
1234/*
1235 * This call will be used for per network namespace operations calls.
1236 * Note: Function will be returned with pipefs_sb_lock taken if superblock was
1237 * found. This lock have to be released by rpc_put_sb_net() when all operations
1238 * will be completed.
1239 */
1240struct super_block *rpc_get_sb_net(const struct net *net)
1241{
1242 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1243
1244 mutex_lock(&sn->pipefs_sb_lock);
1245 if (sn->pipefs_sb)
1246 return sn->pipefs_sb;
1247 mutex_unlock(&sn->pipefs_sb_lock);
1248 return NULL;
1249}
1250EXPORT_SYMBOL_GPL(rpc_get_sb_net);
1251
1252void rpc_put_sb_net(const struct net *net)
1253{
1254 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1255
1256 WARN_ON(sn->pipefs_sb == NULL);
1257 mutex_unlock(&sn->pipefs_sb_lock);
1258}
1259EXPORT_SYMBOL_GPL(rpc_put_sb_net);
1260
1261static const struct rpc_filelist gssd_dummy_clnt_dir[] = {
1262 [0] = {
1263 .name = "clntXX",
1264 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1265 },
1266};
1267
1268static ssize_t
1269dummy_downcall(struct file *filp, const char __user *src, size_t len)
1270{
1271 return -EINVAL;
1272}
1273
1274static const struct rpc_pipe_ops gssd_dummy_pipe_ops = {
1275 .upcall = rpc_pipe_generic_upcall,
1276 .downcall = dummy_downcall,
1277};
1278
1279/*
1280 * Here we present a bogus "info" file to keep rpc.gssd happy. We don't expect
1281 * that it will ever use this info to handle an upcall, but rpc.gssd expects
1282 * that this file will be there and have a certain format.
1283 */
1284static int
1285rpc_show_dummy_info(struct seq_file *m, void *v)
1286{
1287 seq_printf(m, "RPC server: %s\n", utsname()->nodename);
1288 seq_printf(m, "service: foo (1) version 0\n");
1289 seq_printf(m, "address: 127.0.0.1\n");
1290 seq_printf(m, "protocol: tcp\n");
1291 seq_printf(m, "port: 0\n");
1292 return 0;
1293}
1294
1295static int
1296rpc_dummy_info_open(struct inode *inode, struct file *file)
1297{
1298 return single_open(file, rpc_show_dummy_info, NULL);
1299}
1300
1301static const struct file_operations rpc_dummy_info_operations = {
1302 .owner = THIS_MODULE,
1303 .open = rpc_dummy_info_open,
1304 .read = seq_read,
1305 .llseek = seq_lseek,
1306 .release = single_release,
1307};
1308
1309static const struct rpc_filelist gssd_dummy_info_file[] = {
1310 [0] = {
1311 .name = "info",
1312 .i_fop = &rpc_dummy_info_operations,
1313 .mode = S_IFREG | S_IRUSR,
1314 },
1315};
1316
1317/**
1318 * rpc_gssd_dummy_populate - create a dummy gssd pipe
1319 * @root: root of the rpc_pipefs filesystem
1320 * @pipe_data: pipe data created when netns is initialized
1321 *
1322 * Create a dummy set of directories and a pipe that gssd can hold open to
1323 * indicate that it is up and running.
1324 */
1325static struct dentry *
1326rpc_gssd_dummy_populate(struct dentry *root, struct rpc_pipe *pipe_data)
1327{
1328 int ret = 0;
1329 struct dentry *gssd_dentry;
1330 struct dentry *clnt_dentry = NULL;
1331 struct dentry *pipe_dentry = NULL;
1332 struct qstr q = QSTR_INIT(files[RPCAUTH_gssd].name,
1333 strlen(files[RPCAUTH_gssd].name));
1334
1335 /* We should never get this far if "gssd" doesn't exist */
1336 gssd_dentry = d_hash_and_lookup(root, &q);
1337 if (!gssd_dentry)
1338 return ERR_PTR(-ENOENT);
1339
1340 ret = rpc_populate(gssd_dentry, gssd_dummy_clnt_dir, 0, 1, NULL);
1341 if (ret) {
1342 pipe_dentry = ERR_PTR(ret);
1343 goto out;
1344 }
1345
1346 q.name = gssd_dummy_clnt_dir[0].name;
1347 q.len = strlen(gssd_dummy_clnt_dir[0].name);
1348 clnt_dentry = d_hash_and_lookup(gssd_dentry, &q);
1349 if (!clnt_dentry) {
1350 pipe_dentry = ERR_PTR(-ENOENT);
1351 goto out;
1352 }
1353
1354 ret = rpc_populate(clnt_dentry, gssd_dummy_info_file, 0, 1, NULL);
1355 if (ret) {
1356 __rpc_depopulate(gssd_dentry, gssd_dummy_clnt_dir, 0, 1);
1357 pipe_dentry = ERR_PTR(ret);
1358 goto out;
1359 }
1360
1361 pipe_dentry = rpc_mkpipe_dentry(clnt_dentry, "gssd", NULL, pipe_data);
1362 if (IS_ERR(pipe_dentry)) {
1363 __rpc_depopulate(clnt_dentry, gssd_dummy_info_file, 0, 1);
1364 __rpc_depopulate(gssd_dentry, gssd_dummy_clnt_dir, 0, 1);
1365 }
1366out:
1367 dput(clnt_dentry);
1368 dput(gssd_dentry);
1369 return pipe_dentry;
1370}
1371
1372static void
1373rpc_gssd_dummy_depopulate(struct dentry *pipe_dentry)
1374{
1375 struct dentry *clnt_dir = pipe_dentry->d_parent;
1376 struct dentry *gssd_dir = clnt_dir->d_parent;
1377
1378 __rpc_rmpipe(clnt_dir->d_inode, pipe_dentry);
1379 __rpc_depopulate(clnt_dir, gssd_dummy_info_file, 0, 1);
1380 __rpc_depopulate(gssd_dir, gssd_dummy_clnt_dir, 0, 1);
1381 dput(pipe_dentry);
1382}
1383
1384static int
1385rpc_fill_super(struct super_block *sb, void *data, int silent)
1386{
1387 struct inode *inode;
1388 struct dentry *root, *gssd_dentry;
1389 struct net *net = data;
1390 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1391 int err;
1392
1393 sb->s_blocksize = PAGE_CACHE_SIZE;
1394 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
1395 sb->s_magic = RPCAUTH_GSSMAGIC;
1396 sb->s_op = &s_ops;
1397 sb->s_d_op = &simple_dentry_operations;
1398 sb->s_time_gran = 1;
1399
1400 inode = rpc_get_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);
1401 sb->s_root = root = d_make_root(inode);
1402 if (!root)
1403 return -ENOMEM;
1404 if (rpc_populate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF, NULL))
1405 return -ENOMEM;
1406
1407 gssd_dentry = rpc_gssd_dummy_populate(root, sn->gssd_dummy);
1408 if (IS_ERR(gssd_dentry)) {
1409 __rpc_depopulate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF);
1410 return PTR_ERR(gssd_dentry);
1411 }
1412
1413 dprintk("RPC: sending pipefs MOUNT notification for net %p%s\n",
1414 net, NET_NAME(net));
1415 mutex_lock(&sn->pipefs_sb_lock);
1416 sn->pipefs_sb = sb;
1417 err = blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1418 RPC_PIPEFS_MOUNT,
1419 sb);
1420 if (err)
1421 goto err_depopulate;
1422 sb->s_fs_info = get_net(net);
1423 mutex_unlock(&sn->pipefs_sb_lock);
1424 return 0;
1425
1426err_depopulate:
1427 rpc_gssd_dummy_depopulate(gssd_dentry);
1428 blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1429 RPC_PIPEFS_UMOUNT,
1430 sb);
1431 sn->pipefs_sb = NULL;
1432 __rpc_depopulate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF);
1433 mutex_unlock(&sn->pipefs_sb_lock);
1434 return err;
1435}
1436
1437bool
1438gssd_running(struct net *net)
1439{
1440 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1441 struct rpc_pipe *pipe = sn->gssd_dummy;
1442
1443 return pipe->nreaders || pipe->nwriters;
1444}
1445EXPORT_SYMBOL_GPL(gssd_running);
1446
1447static struct dentry *
1448rpc_mount(struct file_system_type *fs_type,
1449 int flags, const char *dev_name, void *data)
1450{
1451 return mount_ns(fs_type, flags, current->nsproxy->net_ns, rpc_fill_super);
1452}
1453
1454static void rpc_kill_sb(struct super_block *sb)
1455{
1456 struct net *net = sb->s_fs_info;
1457 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1458
1459 mutex_lock(&sn->pipefs_sb_lock);
1460 if (sn->pipefs_sb != sb) {
1461 mutex_unlock(&sn->pipefs_sb_lock);
1462 goto out;
1463 }
1464 sn->pipefs_sb = NULL;
1465 dprintk("RPC: sending pipefs UMOUNT notification for net %p%s\n",
1466 net, NET_NAME(net));
1467 blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1468 RPC_PIPEFS_UMOUNT,
1469 sb);
1470 mutex_unlock(&sn->pipefs_sb_lock);
1471 put_net(net);
1472out:
1473 kill_litter_super(sb);
1474}
1475
1476static struct file_system_type rpc_pipe_fs_type = {
1477 .owner = THIS_MODULE,
1478 .name = "rpc_pipefs",
1479 .mount = rpc_mount,
1480 .kill_sb = rpc_kill_sb,
1481};
1482MODULE_ALIAS_FS("rpc_pipefs");
1483MODULE_ALIAS("rpc_pipefs");
1484
1485static void
1486init_once(void *foo)
1487{
1488 struct rpc_inode *rpci = (struct rpc_inode *) foo;
1489
1490 inode_init_once(&rpci->vfs_inode);
1491 rpci->private = NULL;
1492 rpci->pipe = NULL;
1493 init_waitqueue_head(&rpci->waitq);
1494}
1495
1496int register_rpc_pipefs(void)
1497{
1498 int err;
1499
1500 rpc_inode_cachep = kmem_cache_create("rpc_inode_cache",
1501 sizeof(struct rpc_inode),
1502 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
1503 SLAB_MEM_SPREAD),
1504 init_once);
1505 if (!rpc_inode_cachep)
1506 return -ENOMEM;
1507 err = rpc_clients_notifier_register();
1508 if (err)
1509 goto err_notifier;
1510 err = register_filesystem(&rpc_pipe_fs_type);
1511 if (err)
1512 goto err_register;
1513 return 0;
1514
1515err_register:
1516 rpc_clients_notifier_unregister();
1517err_notifier:
1518 kmem_cache_destroy(rpc_inode_cachep);
1519 return err;
1520}
1521
1522void unregister_rpc_pipefs(void)
1523{
1524 rpc_clients_notifier_unregister();
1525 kmem_cache_destroy(rpc_inode_cachep);
1526 unregister_filesystem(&rpc_pipe_fs_type);
1527}