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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(d_inode(dentry))->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(d_inode(dentry))->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 inode_lock(inode);
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 inode_unlock(inode);
192}
193
194static struct inode *
195rpc_alloc_inode(struct super_block *sb)
196{
197 struct rpc_inode *rpci;
198 rpci = 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 inode_lock(inode);
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 inode_unlock(inode);
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 inode_lock(inode);
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 inode_unlock(inode);
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 inode_lock(inode);
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 inode_unlock(inode);
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 inode_lock(inode);
336 res = -EPIPE;
337 if (RPC_I(inode)->pipe != NULL)
338 res = RPC_I(inode)->pipe->ops->downcall(filp, buf, len);
339 inode_unlock(inode);
340 return res;
341}
342
343static __poll_t
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 __poll_t mask = EPOLLOUT | EPOLLWRNORM;
349
350 poll_wait(filp, &rpci->waitq, wait);
351
352 inode_lock(inode);
353 if (rpci->pipe == NULL)
354 mask |= EPOLLERR | EPOLLHUP;
355 else if (filp->private_data || !list_empty(&rpci->pipe->pipe))
356 mask |= EPOLLIN | EPOLLRDNORM;
357 inode_unlock(inode);
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 inode_lock(inode);
371 pipe = RPC_I(inode)->pipe;
372 if (pipe == NULL) {
373 inode_unlock(inode);
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 inode_unlock(inode);
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(inode);
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(d_inode(dentry));
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 = d_inode(parent);
620 inode_lock_nested(dir, I_MUTEX_PARENT);
621 error = __rpc_rmdir(dir, dentry);
622 inode_unlock(dir);
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 = d_inode(dentry);
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 (d_really_is_negative(dentry))
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 = d_inode(parent);
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 (d_really_is_negative(dentry))
683 goto next;
684 switch (d_inode(dentry)->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 = d_inode(parent);
703
704 inode_lock_nested(dir, I_MUTEX_CHILD);
705 __rpc_depopulate(parent, files, start, eof);
706 inode_unlock(dir);
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 = d_inode(parent);
715 struct dentry *dentry;
716 int i, err;
717
718 inode_lock(dir);
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 inode_unlock(dir);
743 return 0;
744out_bad:
745 __rpc_depopulate(parent, files, start, eof);
746 inode_unlock(dir);
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 = d_inode(parent);
758 int error;
759
760 inode_lock_nested(dir, 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 inode_unlock(dir);
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 = d_inode(parent);
791 inode_lock_nested(dir, I_MUTEX_PARENT);
792 if (depopulate != NULL)
793 depopulate(dentry);
794 error = __rpc_rmdir(dir, dentry);
795 inode_unlock(dir);
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 = d_inode(parent);
823 umode_t umode = S_IFIFO | 0600;
824 int err;
825
826 if (pipe->ops->upcall == NULL)
827 umode &= ~0444;
828 if (pipe->ops->downcall == NULL)
829 umode &= ~0222;
830
831 inode_lock_nested(dir, 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 inode_unlock(dir);
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 = d_inode(parent);
868 inode_lock_nested(dir, I_MUTEX_PARENT);
869 error = __rpc_rmpipe(dir, dentry);
870 inode_unlock(dir);
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 | 0400,
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, 0555, 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 | 0600,
1100 },
1101 [1] = {
1102 .name = "content",
1103 .i_fop = &content_file_operations_pipefs,
1104 .mode = S_IFREG | 0400,
1105 },
1106 [2] = {
1107 .name = "flush",
1108 .i_fop = &cache_flush_operations_pipefs,
1109 .mode = S_IFREG | 0600,
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 | 0555,
1168 },
1169 [RPCAUTH_mount] = {
1170 .name = "mount",
1171 .mode = S_IFDIR | 0555,
1172 },
1173 [RPCAUTH_nfs] = {
1174 .name = "nfs",
1175 .mode = S_IFDIR | 0555,
1176 },
1177 [RPCAUTH_portmap] = {
1178 .name = "portmap",
1179 .mode = S_IFDIR | 0555,
1180 },
1181 [RPCAUTH_statd] = {
1182 .name = "statd",
1183 .mode = S_IFDIR | 0555,
1184 },
1185 [RPCAUTH_nfsd4_cb] = {
1186 .name = "nfsd4_cb",
1187 .mode = S_IFDIR | 0555,
1188 },
1189 [RPCAUTH_cache] = {
1190 .name = "cache",
1191 .mode = S_IFDIR | 0555,
1192 },
1193 [RPCAUTH_nfsd] = {
1194 .name = "nfsd",
1195 .mode = S_IFDIR | 0555,
1196 },
1197 [RPCAUTH_gssd] = {
1198 .name = "gssd",
1199 .mode = S_IFDIR | 0555,
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 | 0555,
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 | 0400,
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 dget(pipe_dentry);
1379 __rpc_rmpipe(d_inode(clnt_dir), pipe_dentry);
1380 __rpc_depopulate(clnt_dir, gssd_dummy_info_file, 0, 1);
1381 __rpc_depopulate(gssd_dir, gssd_dummy_clnt_dir, 0, 1);
1382 dput(pipe_dentry);
1383}
1384
1385static int
1386rpc_fill_super(struct super_block *sb, void *data, int silent)
1387{
1388 struct inode *inode;
1389 struct dentry *root, *gssd_dentry;
1390 struct net *net = get_net(sb->s_fs_info);
1391 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1392 int err;
1393
1394 sb->s_blocksize = PAGE_SIZE;
1395 sb->s_blocksize_bits = PAGE_SHIFT;
1396 sb->s_magic = RPCAUTH_GSSMAGIC;
1397 sb->s_op = &s_ops;
1398 sb->s_d_op = &simple_dentry_operations;
1399 sb->s_time_gran = 1;
1400
1401 inode = rpc_get_inode(sb, S_IFDIR | 0555);
1402 sb->s_root = root = d_make_root(inode);
1403 if (!root)
1404 return -ENOMEM;
1405 if (rpc_populate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF, NULL))
1406 return -ENOMEM;
1407
1408 gssd_dentry = rpc_gssd_dummy_populate(root, sn->gssd_dummy);
1409 if (IS_ERR(gssd_dentry)) {
1410 __rpc_depopulate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF);
1411 return PTR_ERR(gssd_dentry);
1412 }
1413
1414 dprintk("RPC: sending pipefs MOUNT notification for net %x%s\n",
1415 net->ns.inum, NET_NAME(net));
1416 mutex_lock(&sn->pipefs_sb_lock);
1417 sn->pipefs_sb = sb;
1418 err = blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1419 RPC_PIPEFS_MOUNT,
1420 sb);
1421 if (err)
1422 goto err_depopulate;
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 struct net *net = current->nsproxy->net_ns;
1452 return mount_ns(fs_type, flags, data, net, net->user_ns, rpc_fill_super);
1453}
1454
1455static void rpc_kill_sb(struct super_block *sb)
1456{
1457 struct net *net = sb->s_fs_info;
1458 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1459
1460 mutex_lock(&sn->pipefs_sb_lock);
1461 if (sn->pipefs_sb != sb) {
1462 mutex_unlock(&sn->pipefs_sb_lock);
1463 goto out;
1464 }
1465 sn->pipefs_sb = NULL;
1466 dprintk("RPC: sending pipefs UMOUNT notification for net %x%s\n",
1467 net->ns.inum, NET_NAME(net));
1468 blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1469 RPC_PIPEFS_UMOUNT,
1470 sb);
1471 mutex_unlock(&sn->pipefs_sb_lock);
1472out:
1473 kill_litter_super(sb);
1474 put_net(net);
1475}
1476
1477static struct file_system_type rpc_pipe_fs_type = {
1478 .owner = THIS_MODULE,
1479 .name = "rpc_pipefs",
1480 .mount = rpc_mount,
1481 .kill_sb = rpc_kill_sb,
1482};
1483MODULE_ALIAS_FS("rpc_pipefs");
1484MODULE_ALIAS("rpc_pipefs");
1485
1486static void
1487init_once(void *foo)
1488{
1489 struct rpc_inode *rpci = (struct rpc_inode *) foo;
1490
1491 inode_init_once(&rpci->vfs_inode);
1492 rpci->private = NULL;
1493 rpci->pipe = NULL;
1494 init_waitqueue_head(&rpci->waitq);
1495}
1496
1497int register_rpc_pipefs(void)
1498{
1499 int err;
1500
1501 rpc_inode_cachep = kmem_cache_create("rpc_inode_cache",
1502 sizeof(struct rpc_inode),
1503 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
1504 SLAB_MEM_SPREAD|SLAB_ACCOUNT),
1505 init_once);
1506 if (!rpc_inode_cachep)
1507 return -ENOMEM;
1508 err = rpc_clients_notifier_register();
1509 if (err)
1510 goto err_notifier;
1511 err = register_filesystem(&rpc_pipe_fs_type);
1512 if (err)
1513 goto err_register;
1514 return 0;
1515
1516err_register:
1517 rpc_clients_notifier_unregister();
1518err_notifier:
1519 kmem_cache_destroy(rpc_inode_cachep);
1520 return err;
1521}
1522
1523void unregister_rpc_pipefs(void)
1524{
1525 rpc_clients_notifier_unregister();
1526 kmem_cache_destroy(rpc_inode_cachep);
1527 unregister_filesystem(&rpc_pipe_fs_type);
1528}
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");