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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
21#include <asm/ioctls.h>
22#include <linux/poll.h>
23#include <linux/wait.h>
24#include <linux/seq_file.h>
25
26#include <linux/sunrpc/clnt.h>
27#include <linux/workqueue.h>
28#include <linux/sunrpc/rpc_pipe_fs.h>
29#include <linux/sunrpc/cache.h>
30#include <linux/nsproxy.h>
31#include <linux/notifier.h>
32
33#include "netns.h"
34#include "sunrpc.h"
35
36#define RPCDBG_FACILITY RPCDBG_DEBUG
37
38#define NET_NAME(net) ((net == &init_net) ? " (init_net)" : "")
39
40static struct file_system_type rpc_pipe_fs_type;
41
42
43static struct kmem_cache *rpc_inode_cachep __read_mostly;
44
45#define RPC_UPCALL_TIMEOUT (30*HZ)
46
47static BLOCKING_NOTIFIER_HEAD(rpc_pipefs_notifier_list);
48
49int rpc_pipefs_notifier_register(struct notifier_block *nb)
50{
51 return blocking_notifier_chain_cond_register(&rpc_pipefs_notifier_list, nb);
52}
53EXPORT_SYMBOL_GPL(rpc_pipefs_notifier_register);
54
55void rpc_pipefs_notifier_unregister(struct notifier_block *nb)
56{
57 blocking_notifier_chain_unregister(&rpc_pipefs_notifier_list, nb);
58}
59EXPORT_SYMBOL_GPL(rpc_pipefs_notifier_unregister);
60
61static void rpc_purge_list(wait_queue_head_t *waitq, struct list_head *head,
62 void (*destroy_msg)(struct rpc_pipe_msg *), int err)
63{
64 struct rpc_pipe_msg *msg;
65
66 if (list_empty(head))
67 return;
68 do {
69 msg = list_entry(head->next, struct rpc_pipe_msg, list);
70 list_del_init(&msg->list);
71 msg->errno = err;
72 destroy_msg(msg);
73 } while (!list_empty(head));
74
75 if (waitq)
76 wake_up(waitq);
77}
78
79static void
80rpc_timeout_upcall_queue(struct work_struct *work)
81{
82 LIST_HEAD(free_list);
83 struct rpc_pipe *pipe =
84 container_of(work, struct rpc_pipe, queue_timeout.work);
85 void (*destroy_msg)(struct rpc_pipe_msg *);
86 struct dentry *dentry;
87
88 spin_lock(&pipe->lock);
89 destroy_msg = pipe->ops->destroy_msg;
90 if (pipe->nreaders == 0) {
91 list_splice_init(&pipe->pipe, &free_list);
92 pipe->pipelen = 0;
93 }
94 dentry = dget(pipe->dentry);
95 spin_unlock(&pipe->lock);
96 rpc_purge_list(dentry ? &RPC_I(dentry->d_inode)->waitq : NULL,
97 &free_list, destroy_msg, -ETIMEDOUT);
98 dput(dentry);
99}
100
101ssize_t rpc_pipe_generic_upcall(struct file *filp, struct rpc_pipe_msg *msg,
102 char __user *dst, size_t buflen)
103{
104 char *data = (char *)msg->data + msg->copied;
105 size_t mlen = min(msg->len - msg->copied, buflen);
106 unsigned long left;
107
108 left = copy_to_user(dst, data, mlen);
109 if (left == mlen) {
110 msg->errno = -EFAULT;
111 return -EFAULT;
112 }
113
114 mlen -= left;
115 msg->copied += mlen;
116 msg->errno = 0;
117 return mlen;
118}
119EXPORT_SYMBOL_GPL(rpc_pipe_generic_upcall);
120
121/**
122 * rpc_queue_upcall - queue an upcall message to userspace
123 * @pipe: upcall pipe on which to queue given message
124 * @msg: message to queue
125 *
126 * Call with an @inode created by rpc_mkpipe() to queue an upcall.
127 * A userspace process may then later read the upcall by performing a
128 * read on an open file for this inode. It is up to the caller to
129 * initialize the fields of @msg (other than @msg->list) appropriately.
130 */
131int
132rpc_queue_upcall(struct rpc_pipe *pipe, struct rpc_pipe_msg *msg)
133{
134 int res = -EPIPE;
135 struct dentry *dentry;
136
137 spin_lock(&pipe->lock);
138 if (pipe->nreaders) {
139 list_add_tail(&msg->list, &pipe->pipe);
140 pipe->pipelen += msg->len;
141 res = 0;
142 } else if (pipe->flags & RPC_PIPE_WAIT_FOR_OPEN) {
143 if (list_empty(&pipe->pipe))
144 queue_delayed_work(rpciod_workqueue,
145 &pipe->queue_timeout,
146 RPC_UPCALL_TIMEOUT);
147 list_add_tail(&msg->list, &pipe->pipe);
148 pipe->pipelen += msg->len;
149 res = 0;
150 }
151 dentry = dget(pipe->dentry);
152 spin_unlock(&pipe->lock);
153 if (dentry) {
154 wake_up(&RPC_I(dentry->d_inode)->waitq);
155 dput(dentry);
156 }
157 return res;
158}
159EXPORT_SYMBOL_GPL(rpc_queue_upcall);
160
161static inline void
162rpc_inode_setowner(struct inode *inode, void *private)
163{
164 RPC_I(inode)->private = private;
165}
166
167static void
168rpc_close_pipes(struct inode *inode)
169{
170 struct rpc_pipe *pipe = RPC_I(inode)->pipe;
171 int need_release;
172 LIST_HEAD(free_list);
173
174 mutex_lock(&inode->i_mutex);
175 spin_lock(&pipe->lock);
176 need_release = pipe->nreaders != 0 || pipe->nwriters != 0;
177 pipe->nreaders = 0;
178 list_splice_init(&pipe->in_upcall, &free_list);
179 list_splice_init(&pipe->pipe, &free_list);
180 pipe->pipelen = 0;
181 pipe->dentry = NULL;
182 spin_unlock(&pipe->lock);
183 rpc_purge_list(&RPC_I(inode)->waitq, &free_list, pipe->ops->destroy_msg, -EPIPE);
184 pipe->nwriters = 0;
185 if (need_release && pipe->ops->release_pipe)
186 pipe->ops->release_pipe(inode);
187 cancel_delayed_work_sync(&pipe->queue_timeout);
188 rpc_inode_setowner(inode, NULL);
189 RPC_I(inode)->pipe = NULL;
190 mutex_unlock(&inode->i_mutex);
191}
192
193static struct inode *
194rpc_alloc_inode(struct super_block *sb)
195{
196 struct rpc_inode *rpci;
197 rpci = (struct rpc_inode *)kmem_cache_alloc(rpc_inode_cachep, GFP_KERNEL);
198 if (!rpci)
199 return NULL;
200 return &rpci->vfs_inode;
201}
202
203static void
204rpc_i_callback(struct rcu_head *head)
205{
206 struct inode *inode = container_of(head, struct inode, i_rcu);
207 kmem_cache_free(rpc_inode_cachep, RPC_I(inode));
208}
209
210static void
211rpc_destroy_inode(struct inode *inode)
212{
213 call_rcu(&inode->i_rcu, rpc_i_callback);
214}
215
216static int
217rpc_pipe_open(struct inode *inode, struct file *filp)
218{
219 struct rpc_pipe *pipe;
220 int first_open;
221 int res = -ENXIO;
222
223 mutex_lock(&inode->i_mutex);
224 pipe = RPC_I(inode)->pipe;
225 if (pipe == NULL)
226 goto out;
227 first_open = pipe->nreaders == 0 && pipe->nwriters == 0;
228 if (first_open && pipe->ops->open_pipe) {
229 res = pipe->ops->open_pipe(inode);
230 if (res)
231 goto out;
232 }
233 if (filp->f_mode & FMODE_READ)
234 pipe->nreaders++;
235 if (filp->f_mode & FMODE_WRITE)
236 pipe->nwriters++;
237 res = 0;
238out:
239 mutex_unlock(&inode->i_mutex);
240 return res;
241}
242
243static int
244rpc_pipe_release(struct inode *inode, struct file *filp)
245{
246 struct rpc_pipe *pipe;
247 struct rpc_pipe_msg *msg;
248 int last_close;
249
250 mutex_lock(&inode->i_mutex);
251 pipe = RPC_I(inode)->pipe;
252 if (pipe == NULL)
253 goto out;
254 msg = filp->private_data;
255 if (msg != NULL) {
256 spin_lock(&pipe->lock);
257 msg->errno = -EAGAIN;
258 list_del_init(&msg->list);
259 spin_unlock(&pipe->lock);
260 pipe->ops->destroy_msg(msg);
261 }
262 if (filp->f_mode & FMODE_WRITE)
263 pipe->nwriters --;
264 if (filp->f_mode & FMODE_READ) {
265 pipe->nreaders --;
266 if (pipe->nreaders == 0) {
267 LIST_HEAD(free_list);
268 spin_lock(&pipe->lock);
269 list_splice_init(&pipe->pipe, &free_list);
270 pipe->pipelen = 0;
271 spin_unlock(&pipe->lock);
272 rpc_purge_list(&RPC_I(inode)->waitq, &free_list,
273 pipe->ops->destroy_msg, -EAGAIN);
274 }
275 }
276 last_close = pipe->nwriters == 0 && pipe->nreaders == 0;
277 if (last_close && pipe->ops->release_pipe)
278 pipe->ops->release_pipe(inode);
279out:
280 mutex_unlock(&inode->i_mutex);
281 return 0;
282}
283
284static ssize_t
285rpc_pipe_read(struct file *filp, char __user *buf, size_t len, loff_t *offset)
286{
287 struct inode *inode = filp->f_path.dentry->d_inode;
288 struct rpc_pipe *pipe;
289 struct rpc_pipe_msg *msg;
290 int res = 0;
291
292 mutex_lock(&inode->i_mutex);
293 pipe = RPC_I(inode)->pipe;
294 if (pipe == NULL) {
295 res = -EPIPE;
296 goto out_unlock;
297 }
298 msg = filp->private_data;
299 if (msg == NULL) {
300 spin_lock(&pipe->lock);
301 if (!list_empty(&pipe->pipe)) {
302 msg = list_entry(pipe->pipe.next,
303 struct rpc_pipe_msg,
304 list);
305 list_move(&msg->list, &pipe->in_upcall);
306 pipe->pipelen -= msg->len;
307 filp->private_data = msg;
308 msg->copied = 0;
309 }
310 spin_unlock(&pipe->lock);
311 if (msg == NULL)
312 goto out_unlock;
313 }
314 /* NOTE: it is up to the callback to update msg->copied */
315 res = pipe->ops->upcall(filp, msg, buf, len);
316 if (res < 0 || msg->len == msg->copied) {
317 filp->private_data = NULL;
318 spin_lock(&pipe->lock);
319 list_del_init(&msg->list);
320 spin_unlock(&pipe->lock);
321 pipe->ops->destroy_msg(msg);
322 }
323out_unlock:
324 mutex_unlock(&inode->i_mutex);
325 return res;
326}
327
328static ssize_t
329rpc_pipe_write(struct file *filp, const char __user *buf, size_t len, loff_t *offset)
330{
331 struct inode *inode = filp->f_path.dentry->d_inode;
332 int res;
333
334 mutex_lock(&inode->i_mutex);
335 res = -EPIPE;
336 if (RPC_I(inode)->pipe != NULL)
337 res = RPC_I(inode)->pipe->ops->downcall(filp, buf, len);
338 mutex_unlock(&inode->i_mutex);
339 return res;
340}
341
342static unsigned int
343rpc_pipe_poll(struct file *filp, struct poll_table_struct *wait)
344{
345 struct inode *inode = filp->f_path.dentry->d_inode;
346 struct rpc_inode *rpci = RPC_I(inode);
347 unsigned int mask = POLLOUT | POLLWRNORM;
348
349 poll_wait(filp, &rpci->waitq, wait);
350
351 mutex_lock(&inode->i_mutex);
352 if (rpci->pipe == NULL)
353 mask |= POLLERR | POLLHUP;
354 else if (filp->private_data || !list_empty(&rpci->pipe->pipe))
355 mask |= POLLIN | POLLRDNORM;
356 mutex_unlock(&inode->i_mutex);
357 return mask;
358}
359
360static long
361rpc_pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
362{
363 struct inode *inode = filp->f_path.dentry->d_inode;
364 struct rpc_pipe *pipe;
365 int len;
366
367 switch (cmd) {
368 case FIONREAD:
369 mutex_lock(&inode->i_mutex);
370 pipe = RPC_I(inode)->pipe;
371 if (pipe == NULL) {
372 mutex_unlock(&inode->i_mutex);
373 return -EPIPE;
374 }
375 spin_lock(&pipe->lock);
376 len = pipe->pipelen;
377 if (filp->private_data) {
378 struct rpc_pipe_msg *msg;
379 msg = filp->private_data;
380 len += msg->len - msg->copied;
381 }
382 spin_unlock(&pipe->lock);
383 mutex_unlock(&inode->i_mutex);
384 return put_user(len, (int __user *)arg);
385 default:
386 return -EINVAL;
387 }
388}
389
390static const struct file_operations rpc_pipe_fops = {
391 .owner = THIS_MODULE,
392 .llseek = no_llseek,
393 .read = rpc_pipe_read,
394 .write = rpc_pipe_write,
395 .poll = rpc_pipe_poll,
396 .unlocked_ioctl = rpc_pipe_ioctl,
397 .open = rpc_pipe_open,
398 .release = rpc_pipe_release,
399};
400
401static int
402rpc_show_info(struct seq_file *m, void *v)
403{
404 struct rpc_clnt *clnt = m->private;
405
406 rcu_read_lock();
407 seq_printf(m, "RPC server: %s\n",
408 rcu_dereference(clnt->cl_xprt)->servername);
409 seq_printf(m, "service: %s (%d) version %d\n", clnt->cl_protname,
410 clnt->cl_prog, clnt->cl_vers);
411 seq_printf(m, "address: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR));
412 seq_printf(m, "protocol: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_PROTO));
413 seq_printf(m, "port: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_PORT));
414 rcu_read_unlock();
415 return 0;
416}
417
418static int
419rpc_info_open(struct inode *inode, struct file *file)
420{
421 struct rpc_clnt *clnt = NULL;
422 int ret = single_open(file, rpc_show_info, NULL);
423
424 if (!ret) {
425 struct seq_file *m = file->private_data;
426
427 spin_lock(&file->f_path.dentry->d_lock);
428 if (!d_unhashed(file->f_path.dentry))
429 clnt = RPC_I(inode)->private;
430 if (clnt != NULL && atomic_inc_not_zero(&clnt->cl_count)) {
431 spin_unlock(&file->f_path.dentry->d_lock);
432 m->private = clnt;
433 } else {
434 spin_unlock(&file->f_path.dentry->d_lock);
435 single_release(inode, file);
436 ret = -EINVAL;
437 }
438 }
439 return ret;
440}
441
442static int
443rpc_info_release(struct inode *inode, struct file *file)
444{
445 struct seq_file *m = file->private_data;
446 struct rpc_clnt *clnt = (struct rpc_clnt *)m->private;
447
448 if (clnt)
449 rpc_release_client(clnt);
450 return single_release(inode, file);
451}
452
453static const struct file_operations rpc_info_operations = {
454 .owner = THIS_MODULE,
455 .open = rpc_info_open,
456 .read = seq_read,
457 .llseek = seq_lseek,
458 .release = rpc_info_release,
459};
460
461
462/*
463 * Description of fs contents.
464 */
465struct rpc_filelist {
466 const char *name;
467 const struct file_operations *i_fop;
468 umode_t mode;
469};
470
471static int rpc_delete_dentry(const struct dentry *dentry)
472{
473 return 1;
474}
475
476static const struct dentry_operations rpc_dentry_operations = {
477 .d_delete = rpc_delete_dentry,
478};
479
480static struct inode *
481rpc_get_inode(struct super_block *sb, umode_t mode)
482{
483 struct inode *inode = new_inode(sb);
484 if (!inode)
485 return NULL;
486 inode->i_ino = get_next_ino();
487 inode->i_mode = mode;
488 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
489 switch (mode & S_IFMT) {
490 case S_IFDIR:
491 inode->i_fop = &simple_dir_operations;
492 inode->i_op = &simple_dir_inode_operations;
493 inc_nlink(inode);
494 default:
495 break;
496 }
497 return inode;
498}
499
500static int __rpc_create_common(struct inode *dir, struct dentry *dentry,
501 umode_t mode,
502 const struct file_operations *i_fop,
503 void *private)
504{
505 struct inode *inode;
506
507 d_drop(dentry);
508 inode = rpc_get_inode(dir->i_sb, mode);
509 if (!inode)
510 goto out_err;
511 inode->i_ino = iunique(dir->i_sb, 100);
512 if (i_fop)
513 inode->i_fop = i_fop;
514 if (private)
515 rpc_inode_setowner(inode, private);
516 d_add(dentry, inode);
517 return 0;
518out_err:
519 printk(KERN_WARNING "%s: %s failed to allocate inode for dentry %s\n",
520 __FILE__, __func__, dentry->d_name.name);
521 dput(dentry);
522 return -ENOMEM;
523}
524
525static int __rpc_create(struct inode *dir, struct dentry *dentry,
526 umode_t mode,
527 const struct file_operations *i_fop,
528 void *private)
529{
530 int err;
531
532 err = __rpc_create_common(dir, dentry, S_IFREG | mode, i_fop, private);
533 if (err)
534 return err;
535 fsnotify_create(dir, dentry);
536 return 0;
537}
538
539static int __rpc_mkdir(struct inode *dir, struct dentry *dentry,
540 umode_t mode,
541 const struct file_operations *i_fop,
542 void *private)
543{
544 int err;
545
546 err = __rpc_create_common(dir, dentry, S_IFDIR | mode, i_fop, private);
547 if (err)
548 return err;
549 inc_nlink(dir);
550 fsnotify_mkdir(dir, dentry);
551 return 0;
552}
553
554static void
555init_pipe(struct rpc_pipe *pipe)
556{
557 pipe->nreaders = 0;
558 pipe->nwriters = 0;
559 INIT_LIST_HEAD(&pipe->in_upcall);
560 INIT_LIST_HEAD(&pipe->in_downcall);
561 INIT_LIST_HEAD(&pipe->pipe);
562 pipe->pipelen = 0;
563 INIT_DELAYED_WORK(&pipe->queue_timeout,
564 rpc_timeout_upcall_queue);
565 pipe->ops = NULL;
566 spin_lock_init(&pipe->lock);
567 pipe->dentry = NULL;
568}
569
570void rpc_destroy_pipe_data(struct rpc_pipe *pipe)
571{
572 kfree(pipe);
573}
574EXPORT_SYMBOL_GPL(rpc_destroy_pipe_data);
575
576struct rpc_pipe *rpc_mkpipe_data(const struct rpc_pipe_ops *ops, int flags)
577{
578 struct rpc_pipe *pipe;
579
580 pipe = kzalloc(sizeof(struct rpc_pipe), GFP_KERNEL);
581 if (!pipe)
582 return ERR_PTR(-ENOMEM);
583 init_pipe(pipe);
584 pipe->ops = ops;
585 pipe->flags = flags;
586 return pipe;
587}
588EXPORT_SYMBOL_GPL(rpc_mkpipe_data);
589
590static int __rpc_mkpipe_dentry(struct inode *dir, struct dentry *dentry,
591 umode_t mode,
592 const struct file_operations *i_fop,
593 void *private,
594 struct rpc_pipe *pipe)
595{
596 struct rpc_inode *rpci;
597 int err;
598
599 err = __rpc_create_common(dir, dentry, S_IFIFO | mode, i_fop, private);
600 if (err)
601 return err;
602 rpci = RPC_I(dentry->d_inode);
603 rpci->private = private;
604 rpci->pipe = pipe;
605 fsnotify_create(dir, dentry);
606 return 0;
607}
608
609static int __rpc_rmdir(struct inode *dir, struct dentry *dentry)
610{
611 int ret;
612
613 dget(dentry);
614 ret = simple_rmdir(dir, dentry);
615 d_delete(dentry);
616 dput(dentry);
617 return ret;
618}
619
620int rpc_rmdir(struct dentry *dentry)
621{
622 struct dentry *parent;
623 struct inode *dir;
624 int error;
625
626 parent = dget_parent(dentry);
627 dir = parent->d_inode;
628 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
629 error = __rpc_rmdir(dir, dentry);
630 mutex_unlock(&dir->i_mutex);
631 dput(parent);
632 return error;
633}
634EXPORT_SYMBOL_GPL(rpc_rmdir);
635
636static int __rpc_unlink(struct inode *dir, struct dentry *dentry)
637{
638 int ret;
639
640 dget(dentry);
641 ret = simple_unlink(dir, dentry);
642 d_delete(dentry);
643 dput(dentry);
644 return ret;
645}
646
647static int __rpc_rmpipe(struct inode *dir, struct dentry *dentry)
648{
649 struct inode *inode = dentry->d_inode;
650
651 rpc_close_pipes(inode);
652 return __rpc_unlink(dir, dentry);
653}
654
655static struct dentry *__rpc_lookup_create_exclusive(struct dentry *parent,
656 struct qstr *name)
657{
658 struct dentry *dentry;
659
660 dentry = d_lookup(parent, name);
661 if (!dentry) {
662 dentry = d_alloc(parent, name);
663 if (!dentry)
664 return ERR_PTR(-ENOMEM);
665 }
666 if (dentry->d_inode == NULL) {
667 d_set_d_op(dentry, &rpc_dentry_operations);
668 return dentry;
669 }
670 dput(dentry);
671 return ERR_PTR(-EEXIST);
672}
673
674/*
675 * FIXME: This probably has races.
676 */
677static void __rpc_depopulate(struct dentry *parent,
678 const struct rpc_filelist *files,
679 int start, int eof)
680{
681 struct inode *dir = parent->d_inode;
682 struct dentry *dentry;
683 struct qstr name;
684 int i;
685
686 for (i = start; i < eof; i++) {
687 name.name = files[i].name;
688 name.len = strlen(files[i].name);
689 name.hash = full_name_hash(name.name, name.len);
690 dentry = d_lookup(parent, &name);
691
692 if (dentry == NULL)
693 continue;
694 if (dentry->d_inode == NULL)
695 goto next;
696 switch (dentry->d_inode->i_mode & S_IFMT) {
697 default:
698 BUG();
699 case S_IFREG:
700 __rpc_unlink(dir, dentry);
701 break;
702 case S_IFDIR:
703 __rpc_rmdir(dir, dentry);
704 }
705next:
706 dput(dentry);
707 }
708}
709
710static void rpc_depopulate(struct dentry *parent,
711 const struct rpc_filelist *files,
712 int start, int eof)
713{
714 struct inode *dir = parent->d_inode;
715
716 mutex_lock_nested(&dir->i_mutex, I_MUTEX_CHILD);
717 __rpc_depopulate(parent, files, start, eof);
718 mutex_unlock(&dir->i_mutex);
719}
720
721static int rpc_populate(struct dentry *parent,
722 const struct rpc_filelist *files,
723 int start, int eof,
724 void *private)
725{
726 struct inode *dir = parent->d_inode;
727 struct dentry *dentry;
728 int i, err;
729
730 mutex_lock(&dir->i_mutex);
731 for (i = start; i < eof; i++) {
732 struct qstr q;
733
734 q.name = files[i].name;
735 q.len = strlen(files[i].name);
736 q.hash = full_name_hash(q.name, q.len);
737 dentry = __rpc_lookup_create_exclusive(parent, &q);
738 err = PTR_ERR(dentry);
739 if (IS_ERR(dentry))
740 goto out_bad;
741 switch (files[i].mode & S_IFMT) {
742 default:
743 BUG();
744 case S_IFREG:
745 err = __rpc_create(dir, dentry,
746 files[i].mode,
747 files[i].i_fop,
748 private);
749 break;
750 case S_IFDIR:
751 err = __rpc_mkdir(dir, dentry,
752 files[i].mode,
753 NULL,
754 private);
755 }
756 if (err != 0)
757 goto out_bad;
758 }
759 mutex_unlock(&dir->i_mutex);
760 return 0;
761out_bad:
762 __rpc_depopulate(parent, files, start, eof);
763 mutex_unlock(&dir->i_mutex);
764 printk(KERN_WARNING "%s: %s failed to populate directory %s\n",
765 __FILE__, __func__, parent->d_name.name);
766 return err;
767}
768
769static struct dentry *rpc_mkdir_populate(struct dentry *parent,
770 struct qstr *name, umode_t mode, void *private,
771 int (*populate)(struct dentry *, void *), void *args_populate)
772{
773 struct dentry *dentry;
774 struct inode *dir = parent->d_inode;
775 int error;
776
777 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
778 dentry = __rpc_lookup_create_exclusive(parent, name);
779 if (IS_ERR(dentry))
780 goto out;
781 error = __rpc_mkdir(dir, dentry, mode, NULL, private);
782 if (error != 0)
783 goto out_err;
784 if (populate != NULL) {
785 error = populate(dentry, args_populate);
786 if (error)
787 goto err_rmdir;
788 }
789out:
790 mutex_unlock(&dir->i_mutex);
791 return dentry;
792err_rmdir:
793 __rpc_rmdir(dir, dentry);
794out_err:
795 dentry = ERR_PTR(error);
796 goto out;
797}
798
799static int rpc_rmdir_depopulate(struct dentry *dentry,
800 void (*depopulate)(struct dentry *))
801{
802 struct dentry *parent;
803 struct inode *dir;
804 int error;
805
806 parent = dget_parent(dentry);
807 dir = parent->d_inode;
808 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
809 if (depopulate != NULL)
810 depopulate(dentry);
811 error = __rpc_rmdir(dir, dentry);
812 mutex_unlock(&dir->i_mutex);
813 dput(parent);
814 return error;
815}
816
817/**
818 * rpc_mkpipe - make an rpc_pipefs file for kernel<->userspace communication
819 * @parent: dentry of directory to create new "pipe" in
820 * @name: name of pipe
821 * @private: private data to associate with the pipe, for the caller's use
822 * @pipe: &rpc_pipe containing input parameters
823 *
824 * Data is made available for userspace to read by calls to
825 * rpc_queue_upcall(). The actual reads will result in calls to
826 * @ops->upcall, which will be called with the file pointer,
827 * message, and userspace buffer to copy to.
828 *
829 * Writes can come at any time, and do not necessarily have to be
830 * responses to upcalls. They will result in calls to @msg->downcall.
831 *
832 * The @private argument passed here will be available to all these methods
833 * from the file pointer, via RPC_I(file->f_dentry->d_inode)->private.
834 */
835struct dentry *rpc_mkpipe_dentry(struct dentry *parent, const char *name,
836 void *private, struct rpc_pipe *pipe)
837{
838 struct dentry *dentry;
839 struct inode *dir = parent->d_inode;
840 umode_t umode = S_IFIFO | S_IRUSR | S_IWUSR;
841 struct qstr q;
842 int err;
843
844 if (pipe->ops->upcall == NULL)
845 umode &= ~S_IRUGO;
846 if (pipe->ops->downcall == NULL)
847 umode &= ~S_IWUGO;
848
849 q.name = name;
850 q.len = strlen(name);
851 q.hash = full_name_hash(q.name, q.len),
852
853 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
854 dentry = __rpc_lookup_create_exclusive(parent, &q);
855 if (IS_ERR(dentry))
856 goto out;
857 err = __rpc_mkpipe_dentry(dir, dentry, umode, &rpc_pipe_fops,
858 private, pipe);
859 if (err)
860 goto out_err;
861out:
862 mutex_unlock(&dir->i_mutex);
863 return dentry;
864out_err:
865 dentry = ERR_PTR(err);
866 printk(KERN_WARNING "%s: %s() failed to create pipe %s/%s (errno = %d)\n",
867 __FILE__, __func__, parent->d_name.name, name,
868 err);
869 goto out;
870}
871EXPORT_SYMBOL_GPL(rpc_mkpipe_dentry);
872
873/**
874 * rpc_unlink - remove a pipe
875 * @dentry: dentry for the pipe, as returned from rpc_mkpipe
876 *
877 * After this call, lookups will no longer find the pipe, and any
878 * attempts to read or write using preexisting opens of the pipe will
879 * return -EPIPE.
880 */
881int
882rpc_unlink(struct dentry *dentry)
883{
884 struct dentry *parent;
885 struct inode *dir;
886 int error = 0;
887
888 parent = dget_parent(dentry);
889 dir = parent->d_inode;
890 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
891 error = __rpc_rmpipe(dir, dentry);
892 mutex_unlock(&dir->i_mutex);
893 dput(parent);
894 return error;
895}
896EXPORT_SYMBOL_GPL(rpc_unlink);
897
898enum {
899 RPCAUTH_info,
900 RPCAUTH_EOF
901};
902
903static const struct rpc_filelist authfiles[] = {
904 [RPCAUTH_info] = {
905 .name = "info",
906 .i_fop = &rpc_info_operations,
907 .mode = S_IFREG | S_IRUSR,
908 },
909};
910
911static int rpc_clntdir_populate(struct dentry *dentry, void *private)
912{
913 return rpc_populate(dentry,
914 authfiles, RPCAUTH_info, RPCAUTH_EOF,
915 private);
916}
917
918static void rpc_clntdir_depopulate(struct dentry *dentry)
919{
920 rpc_depopulate(dentry, authfiles, RPCAUTH_info, RPCAUTH_EOF);
921}
922
923/**
924 * rpc_create_client_dir - Create a new rpc_client directory in rpc_pipefs
925 * @dentry: dentry from the rpc_pipefs root to the new directory
926 * @name: &struct qstr for the name
927 * @rpc_client: rpc client to associate with this directory
928 *
929 * This creates a directory at the given @path associated with
930 * @rpc_clnt, which will contain a file named "info" with some basic
931 * information about the client, together with any "pipes" that may
932 * later be created using rpc_mkpipe().
933 */
934struct dentry *rpc_create_client_dir(struct dentry *dentry,
935 struct qstr *name,
936 struct rpc_clnt *rpc_client)
937{
938 return rpc_mkdir_populate(dentry, name, S_IRUGO | S_IXUGO, NULL,
939 rpc_clntdir_populate, rpc_client);
940}
941
942/**
943 * rpc_remove_client_dir - Remove a directory created with rpc_create_client_dir()
944 * @dentry: dentry for the pipe
945 */
946int rpc_remove_client_dir(struct dentry *dentry)
947{
948 return rpc_rmdir_depopulate(dentry, rpc_clntdir_depopulate);
949}
950
951static const struct rpc_filelist cache_pipefs_files[3] = {
952 [0] = {
953 .name = "channel",
954 .i_fop = &cache_file_operations_pipefs,
955 .mode = S_IFREG|S_IRUSR|S_IWUSR,
956 },
957 [1] = {
958 .name = "content",
959 .i_fop = &content_file_operations_pipefs,
960 .mode = S_IFREG|S_IRUSR,
961 },
962 [2] = {
963 .name = "flush",
964 .i_fop = &cache_flush_operations_pipefs,
965 .mode = S_IFREG|S_IRUSR|S_IWUSR,
966 },
967};
968
969static int rpc_cachedir_populate(struct dentry *dentry, void *private)
970{
971 return rpc_populate(dentry,
972 cache_pipefs_files, 0, 3,
973 private);
974}
975
976static void rpc_cachedir_depopulate(struct dentry *dentry)
977{
978 rpc_depopulate(dentry, cache_pipefs_files, 0, 3);
979}
980
981struct dentry *rpc_create_cache_dir(struct dentry *parent, struct qstr *name,
982 umode_t umode, struct cache_detail *cd)
983{
984 return rpc_mkdir_populate(parent, name, umode, NULL,
985 rpc_cachedir_populate, cd);
986}
987
988void rpc_remove_cache_dir(struct dentry *dentry)
989{
990 rpc_rmdir_depopulate(dentry, rpc_cachedir_depopulate);
991}
992
993/*
994 * populate the filesystem
995 */
996static const struct super_operations s_ops = {
997 .alloc_inode = rpc_alloc_inode,
998 .destroy_inode = rpc_destroy_inode,
999 .statfs = simple_statfs,
1000};
1001
1002#define RPCAUTH_GSSMAGIC 0x67596969
1003
1004/*
1005 * We have a single directory with 1 node in it.
1006 */
1007enum {
1008 RPCAUTH_lockd,
1009 RPCAUTH_mount,
1010 RPCAUTH_nfs,
1011 RPCAUTH_portmap,
1012 RPCAUTH_statd,
1013 RPCAUTH_nfsd4_cb,
1014 RPCAUTH_cache,
1015 RPCAUTH_nfsd,
1016 RPCAUTH_RootEOF
1017};
1018
1019static const struct rpc_filelist files[] = {
1020 [RPCAUTH_lockd] = {
1021 .name = "lockd",
1022 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1023 },
1024 [RPCAUTH_mount] = {
1025 .name = "mount",
1026 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1027 },
1028 [RPCAUTH_nfs] = {
1029 .name = "nfs",
1030 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1031 },
1032 [RPCAUTH_portmap] = {
1033 .name = "portmap",
1034 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1035 },
1036 [RPCAUTH_statd] = {
1037 .name = "statd",
1038 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1039 },
1040 [RPCAUTH_nfsd4_cb] = {
1041 .name = "nfsd4_cb",
1042 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1043 },
1044 [RPCAUTH_cache] = {
1045 .name = "cache",
1046 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1047 },
1048 [RPCAUTH_nfsd] = {
1049 .name = "nfsd",
1050 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1051 },
1052};
1053
1054/*
1055 * This call can be used only in RPC pipefs mount notification hooks.
1056 */
1057struct dentry *rpc_d_lookup_sb(const struct super_block *sb,
1058 const unsigned char *dir_name)
1059{
1060 struct qstr dir = QSTR_INIT(dir_name, strlen(dir_name));
1061
1062 dir.hash = full_name_hash(dir.name, dir.len);
1063 return d_lookup(sb->s_root, &dir);
1064}
1065EXPORT_SYMBOL_GPL(rpc_d_lookup_sb);
1066
1067void rpc_pipefs_init_net(struct net *net)
1068{
1069 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1070
1071 mutex_init(&sn->pipefs_sb_lock);
1072}
1073
1074/*
1075 * This call will be used for per network namespace operations calls.
1076 * Note: Function will be returned with pipefs_sb_lock taken if superblock was
1077 * found. This lock have to be released by rpc_put_sb_net() when all operations
1078 * will be completed.
1079 */
1080struct super_block *rpc_get_sb_net(const struct net *net)
1081{
1082 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1083
1084 mutex_lock(&sn->pipefs_sb_lock);
1085 if (sn->pipefs_sb)
1086 return sn->pipefs_sb;
1087 mutex_unlock(&sn->pipefs_sb_lock);
1088 return NULL;
1089}
1090EXPORT_SYMBOL_GPL(rpc_get_sb_net);
1091
1092void rpc_put_sb_net(const struct net *net)
1093{
1094 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1095
1096 BUG_ON(sn->pipefs_sb == NULL);
1097 mutex_unlock(&sn->pipefs_sb_lock);
1098}
1099EXPORT_SYMBOL_GPL(rpc_put_sb_net);
1100
1101static int
1102rpc_fill_super(struct super_block *sb, void *data, int silent)
1103{
1104 struct inode *inode;
1105 struct dentry *root;
1106 struct net *net = data;
1107 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1108 int err;
1109
1110 sb->s_blocksize = PAGE_CACHE_SIZE;
1111 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
1112 sb->s_magic = RPCAUTH_GSSMAGIC;
1113 sb->s_op = &s_ops;
1114 sb->s_time_gran = 1;
1115
1116 inode = rpc_get_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);
1117 sb->s_root = root = d_make_root(inode);
1118 if (!root)
1119 return -ENOMEM;
1120 if (rpc_populate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF, NULL))
1121 return -ENOMEM;
1122 dprintk("RPC: sending pipefs MOUNT notification for net %p%s\n", net,
1123 NET_NAME(net));
1124 sn->pipefs_sb = sb;
1125 err = blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1126 RPC_PIPEFS_MOUNT,
1127 sb);
1128 if (err)
1129 goto err_depopulate;
1130 sb->s_fs_info = get_net(net);
1131 return 0;
1132
1133err_depopulate:
1134 blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1135 RPC_PIPEFS_UMOUNT,
1136 sb);
1137 sn->pipefs_sb = NULL;
1138 __rpc_depopulate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF);
1139 return err;
1140}
1141
1142static struct dentry *
1143rpc_mount(struct file_system_type *fs_type,
1144 int flags, const char *dev_name, void *data)
1145{
1146 return mount_ns(fs_type, flags, current->nsproxy->net_ns, rpc_fill_super);
1147}
1148
1149static void rpc_kill_sb(struct super_block *sb)
1150{
1151 struct net *net = sb->s_fs_info;
1152 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1153
1154 mutex_lock(&sn->pipefs_sb_lock);
1155 sn->pipefs_sb = NULL;
1156 mutex_unlock(&sn->pipefs_sb_lock);
1157 put_net(net);
1158 dprintk("RPC: sending pipefs UMOUNT notification for net %p%s\n", net,
1159 NET_NAME(net));
1160 blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1161 RPC_PIPEFS_UMOUNT,
1162 sb);
1163 kill_litter_super(sb);
1164}
1165
1166static struct file_system_type rpc_pipe_fs_type = {
1167 .owner = THIS_MODULE,
1168 .name = "rpc_pipefs",
1169 .mount = rpc_mount,
1170 .kill_sb = rpc_kill_sb,
1171};
1172
1173static void
1174init_once(void *foo)
1175{
1176 struct rpc_inode *rpci = (struct rpc_inode *) foo;
1177
1178 inode_init_once(&rpci->vfs_inode);
1179 rpci->private = NULL;
1180 rpci->pipe = NULL;
1181 init_waitqueue_head(&rpci->waitq);
1182}
1183
1184int register_rpc_pipefs(void)
1185{
1186 int err;
1187
1188 rpc_inode_cachep = kmem_cache_create("rpc_inode_cache",
1189 sizeof(struct rpc_inode),
1190 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
1191 SLAB_MEM_SPREAD),
1192 init_once);
1193 if (!rpc_inode_cachep)
1194 return -ENOMEM;
1195 err = rpc_clients_notifier_register();
1196 if (err)
1197 goto err_notifier;
1198 err = register_filesystem(&rpc_pipe_fs_type);
1199 if (err)
1200 goto err_register;
1201 return 0;
1202
1203err_register:
1204 rpc_clients_notifier_unregister();
1205err_notifier:
1206 kmem_cache_destroy(rpc_inode_cachep);
1207 return err;
1208}
1209
1210void unregister_rpc_pipefs(void)
1211{
1212 rpc_clients_notifier_unregister();
1213 kmem_cache_destroy(rpc_inode_cachep);
1214 unregister_filesystem(&rpc_pipe_fs_type);
1215}
1216
1217/* Make 'mount -t rpc_pipefs ...' autoload this module. */
1218MODULE_ALIAS("rpc_pipefs");