projects / deliverable / linux.git / blob
? search:
summary | shortlog | log | commit | commitdiff | tree
blame | history | raw | HEAD
sunrpc: create a new dummy pipe for gssd to hold open
[deliverable/linux.git] / net / sunrpc / rpc_pipe.c
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
40 static struct file_system_type rpc_pipe_fs_type;
41 static const struct rpc_pipe_ops gssd_dummy_pipe_ops;
42
43 static struct kmem_cache *rpc_inode_cachep __read_mostly;
44
45 #define RPC_UPCALL_TIMEOUT (30*HZ)
46
47 static BLOCKING_NOTIFIER_HEAD(rpc_pipefs_notifier_list);
48
49 int rpc_pipefs_notifier_register(struct notifier_block *nb)
50 {
51 return blocking_notifier_chain_cond_register(&rpc_pipefs_notifier_list, nb);
52 }
53 EXPORT_SYMBOL_GPL(rpc_pipefs_notifier_register);
54
55 void rpc_pipefs_notifier_unregister(struct notifier_block *nb)
56 {
57 blocking_notifier_chain_unregister(&rpc_pipefs_notifier_list, nb);
58 }
59 EXPORT_SYMBOL_GPL(rpc_pipefs_notifier_unregister);
60
61 static 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
79 static void
80 rpc_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
101 ssize_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 }
119 EXPORT_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 */
131 int
132 rpc_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 }
159 EXPORT_SYMBOL_GPL(rpc_queue_upcall);
160
161 static inline void
162 rpc_inode_setowner(struct inode *inode, void *private)
163 {
164 RPC_I(inode)->private = private;
165 }
166
167 static void
168 rpc_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
193 static struct inode *
194 rpc_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
203 static void
204 rpc_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
210 static void
211 rpc_destroy_inode(struct inode *inode)
212 {
213 call_rcu(&inode->i_rcu, rpc_i_callback);
214 }
215
216 static int
217 rpc_pipe_open(struct inode *inode, struct file *filp)
218 {
219 struct net *net = inode->i_sb->s_fs_info;
220 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
221 struct rpc_pipe *pipe;
222 int first_open;
223 int res = -ENXIO;
224
225 mutex_lock(&inode->i_mutex);
226 sn->gssd_running = 1;
227 pipe = RPC_I(inode)->pipe;
228 if (pipe == NULL)
229 goto out;
230 first_open = pipe->nreaders == 0 && pipe->nwriters == 0;
231 if (first_open && pipe->ops->open_pipe) {
232 res = pipe->ops->open_pipe(inode);
233 if (res)
234 goto out;
235 }
236 if (filp->f_mode & FMODE_READ)
237 pipe->nreaders++;
238 if (filp->f_mode & FMODE_WRITE)
239 pipe->nwriters++;
240 res = 0;
241 out:
242 mutex_unlock(&inode->i_mutex);
243 return res;
244 }
245
246 static int
247 rpc_pipe_release(struct inode *inode, struct file *filp)
248 {
249 struct rpc_pipe *pipe;
250 struct rpc_pipe_msg *msg;
251 int last_close;
252
253 mutex_lock(&inode->i_mutex);
254 pipe = RPC_I(inode)->pipe;
255 if (pipe == NULL)
256 goto out;
257 msg = filp->private_data;
258 if (msg != NULL) {
259 spin_lock(&pipe->lock);
260 msg->errno = -EAGAIN;
261 list_del_init(&msg->list);
262 spin_unlock(&pipe->lock);
263 pipe->ops->destroy_msg(msg);
264 }
265 if (filp->f_mode & FMODE_WRITE)
266 pipe->nwriters --;
267 if (filp->f_mode & FMODE_READ) {
268 pipe->nreaders --;
269 if (pipe->nreaders == 0) {
270 LIST_HEAD(free_list);
271 spin_lock(&pipe->lock);
272 list_splice_init(&pipe->pipe, &free_list);
273 pipe->pipelen = 0;
274 spin_unlock(&pipe->lock);
275 rpc_purge_list(&RPC_I(inode)->waitq, &free_list,
276 pipe->ops->destroy_msg, -EAGAIN);
277 }
278 }
279 last_close = pipe->nwriters == 0 && pipe->nreaders == 0;
280 if (last_close && pipe->ops->release_pipe)
281 pipe->ops->release_pipe(inode);
282 out:
283 mutex_unlock(&inode->i_mutex);
284 return 0;
285 }
286
287 static ssize_t
288 rpc_pipe_read(struct file *filp, char __user *buf, size_t len, loff_t *offset)
289 {
290 struct inode *inode = file_inode(filp);
291 struct rpc_pipe *pipe;
292 struct rpc_pipe_msg *msg;
293 int res = 0;
294
295 mutex_lock(&inode->i_mutex);
296 pipe = RPC_I(inode)->pipe;
297 if (pipe == NULL) {
298 res = -EPIPE;
299 goto out_unlock;
300 }
301 msg = filp->private_data;
302 if (msg == NULL) {
303 spin_lock(&pipe->lock);
304 if (!list_empty(&pipe->pipe)) {
305 msg = list_entry(pipe->pipe.next,
306 struct rpc_pipe_msg,
307 list);
308 list_move(&msg->list, &pipe->in_upcall);
309 pipe->pipelen -= msg->len;
310 filp->private_data = msg;
311 msg->copied = 0;
312 }
313 spin_unlock(&pipe->lock);
314 if (msg == NULL)
315 goto out_unlock;
316 }
317 /* NOTE: it is up to the callback to update msg->copied */
318 res = pipe->ops->upcall(filp, msg, buf, len);
319 if (res < 0 || msg->len == msg->copied) {
320 filp->private_data = NULL;
321 spin_lock(&pipe->lock);
322 list_del_init(&msg->list);
323 spin_unlock(&pipe->lock);
324 pipe->ops->destroy_msg(msg);
325 }
326 out_unlock:
327 mutex_unlock(&inode->i_mutex);
328 return res;
329 }
330
331 static ssize_t
332 rpc_pipe_write(struct file *filp, const char __user *buf, size_t len, loff_t *offset)
333 {
334 struct inode *inode = file_inode(filp);
335 int res;
336
337 mutex_lock(&inode->i_mutex);
338 res = -EPIPE;
339 if (RPC_I(inode)->pipe != NULL)
340 res = RPC_I(inode)->pipe->ops->downcall(filp, buf, len);
341 mutex_unlock(&inode->i_mutex);
342 return res;
343 }
344
345 static unsigned int
346 rpc_pipe_poll(struct file *filp, struct poll_table_struct *wait)
347 {
348 struct inode *inode = file_inode(filp);
349 struct rpc_inode *rpci = RPC_I(inode);
350 unsigned int mask = POLLOUT | POLLWRNORM;
351
352 poll_wait(filp, &rpci->waitq, wait);
353
354 mutex_lock(&inode->i_mutex);
355 if (rpci->pipe == NULL)
356 mask |= POLLERR | POLLHUP;
357 else if (filp->private_data || !list_empty(&rpci->pipe->pipe))
358 mask |= POLLIN | POLLRDNORM;
359 mutex_unlock(&inode->i_mutex);
360 return mask;
361 }
362
363 static long
364 rpc_pipe_ioctl(struct file *filp, unsigned int cmd, unsigned long arg)
365 {
366 struct inode *inode = file_inode(filp);
367 struct rpc_pipe *pipe;
368 int len;
369
370 switch (cmd) {
371 case FIONREAD:
372 mutex_lock(&inode->i_mutex);
373 pipe = RPC_I(inode)->pipe;
374 if (pipe == NULL) {
375 mutex_unlock(&inode->i_mutex);
376 return -EPIPE;
377 }
378 spin_lock(&pipe->lock);
379 len = pipe->pipelen;
380 if (filp->private_data) {
381 struct rpc_pipe_msg *msg;
382 msg = filp->private_data;
383 len += msg->len - msg->copied;
384 }
385 spin_unlock(&pipe->lock);
386 mutex_unlock(&inode->i_mutex);
387 return put_user(len, (int __user *)arg);
388 default:
389 return -EINVAL;
390 }
391 }
392
393 static const struct file_operations rpc_pipe_fops = {
394 .owner = THIS_MODULE,
395 .llseek = no_llseek,
396 .read = rpc_pipe_read,
397 .write = rpc_pipe_write,
398 .poll = rpc_pipe_poll,
399 .unlocked_ioctl = rpc_pipe_ioctl,
400 .open = rpc_pipe_open,
401 .release = rpc_pipe_release,
402 };
403
404 static int
405 rpc_show_info(struct seq_file *m, void *v)
406 {
407 struct rpc_clnt *clnt = m->private;
408
409 rcu_read_lock();
410 seq_printf(m, "RPC server: %s\n",
411 rcu_dereference(clnt->cl_xprt)->servername);
412 seq_printf(m, "service: %s (%d) version %d\n", clnt->cl_program->name,
413 clnt->cl_prog, clnt->cl_vers);
414 seq_printf(m, "address: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR));
415 seq_printf(m, "protocol: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_PROTO));
416 seq_printf(m, "port: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_PORT));
417 rcu_read_unlock();
418 return 0;
419 }
420
421 static int
422 rpc_info_open(struct inode *inode, struct file *file)
423 {
424 struct rpc_clnt *clnt = NULL;
425 int ret = single_open(file, rpc_show_info, NULL);
426
427 if (!ret) {
428 struct seq_file *m = file->private_data;
429
430 spin_lock(&file->f_path.dentry->d_lock);
431 if (!d_unhashed(file->f_path.dentry))
432 clnt = RPC_I(inode)->private;
433 if (clnt != NULL && atomic_inc_not_zero(&clnt->cl_count)) {
434 spin_unlock(&file->f_path.dentry->d_lock);
435 m->private = clnt;
436 } else {
437 spin_unlock(&file->f_path.dentry->d_lock);
438 single_release(inode, file);
439 ret = -EINVAL;
440 }
441 }
442 return ret;
443 }
444
445 static int
446 rpc_info_release(struct inode *inode, struct file *file)
447 {
448 struct seq_file *m = file->private_data;
449 struct rpc_clnt *clnt = (struct rpc_clnt *)m->private;
450
451 if (clnt)
452 rpc_release_client(clnt);
453 return single_release(inode, file);
454 }
455
456 static const struct file_operations rpc_info_operations = {
457 .owner = THIS_MODULE,
458 .open = rpc_info_open,
459 .read = seq_read,
460 .llseek = seq_lseek,
461 .release = rpc_info_release,
462 };
463
464
465 /*
466 * Description of fs contents.
467 */
468 struct rpc_filelist {
469 const char *name;
470 const struct file_operations *i_fop;
471 umode_t mode;
472 };
473
474 static struct inode *
475 rpc_get_inode(struct super_block *sb, umode_t mode)
476 {
477 struct inode *inode = new_inode(sb);
478 if (!inode)
479 return NULL;
480 inode->i_ino = get_next_ino();
481 inode->i_mode = mode;
482 inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME;
483 switch (mode & S_IFMT) {
484 case S_IFDIR:
485 inode->i_fop = &simple_dir_operations;
486 inode->i_op = &simple_dir_inode_operations;
487 inc_nlink(inode);
488 default:
489 break;
490 }
491 return inode;
492 }
493
494 static int __rpc_create_common(struct inode *dir, struct dentry *dentry,
495 umode_t mode,
496 const struct file_operations *i_fop,
497 void *private)
498 {
499 struct inode *inode;
500
501 d_drop(dentry);
502 inode = rpc_get_inode(dir->i_sb, mode);
503 if (!inode)
504 goto out_err;
505 inode->i_ino = iunique(dir->i_sb, 100);
506 if (i_fop)
507 inode->i_fop = i_fop;
508 if (private)
509 rpc_inode_setowner(inode, private);
510 d_add(dentry, inode);
511 return 0;
512 out_err:
513 printk(KERN_WARNING "%s: %s failed to allocate inode for dentry %pd\n",
514 __FILE__, __func__, dentry);
515 dput(dentry);
516 return -ENOMEM;
517 }
518
519 static int __rpc_create(struct inode *dir, struct dentry *dentry,
520 umode_t mode,
521 const struct file_operations *i_fop,
522 void *private)
523 {
524 int err;
525
526 err = __rpc_create_common(dir, dentry, S_IFREG | mode, i_fop, private);
527 if (err)
528 return err;
529 fsnotify_create(dir, dentry);
530 return 0;
531 }
532
533 static int __rpc_mkdir(struct inode *dir, struct dentry *dentry,
534 umode_t mode,
535 const struct file_operations *i_fop,
536 void *private)
537 {
538 int err;
539
540 err = __rpc_create_common(dir, dentry, S_IFDIR | mode, i_fop, private);
541 if (err)
542 return err;
543 inc_nlink(dir);
544 fsnotify_mkdir(dir, dentry);
545 return 0;
546 }
547
548 static void
549 init_pipe(struct rpc_pipe *pipe)
550 {
551 pipe->nreaders = 0;
552 pipe->nwriters = 0;
553 INIT_LIST_HEAD(&pipe->in_upcall);
554 INIT_LIST_HEAD(&pipe->in_downcall);
555 INIT_LIST_HEAD(&pipe->pipe);
556 pipe->pipelen = 0;
557 INIT_DELAYED_WORK(&pipe->queue_timeout,
558 rpc_timeout_upcall_queue);
559 pipe->ops = NULL;
560 spin_lock_init(&pipe->lock);
561 pipe->dentry = NULL;
562 }
563
564 void rpc_destroy_pipe_data(struct rpc_pipe *pipe)
565 {
566 kfree(pipe);
567 }
568 EXPORT_SYMBOL_GPL(rpc_destroy_pipe_data);
569
570 struct rpc_pipe *rpc_mkpipe_data(const struct rpc_pipe_ops *ops, int flags)
571 {
572 struct rpc_pipe *pipe;
573
574 pipe = kzalloc(sizeof(struct rpc_pipe), GFP_KERNEL);
575 if (!pipe)
576 return ERR_PTR(-ENOMEM);
577 init_pipe(pipe);
578 pipe->ops = ops;
579 pipe->flags = flags;
580 return pipe;
581 }
582 EXPORT_SYMBOL_GPL(rpc_mkpipe_data);
583
584 static int __rpc_mkpipe_dentry(struct inode *dir, struct dentry *dentry,
585 umode_t mode,
586 const struct file_operations *i_fop,
587 void *private,
588 struct rpc_pipe *pipe)
589 {
590 struct rpc_inode *rpci;
591 int err;
592
593 err = __rpc_create_common(dir, dentry, S_IFIFO | mode, i_fop, private);
594 if (err)
595 return err;
596 rpci = RPC_I(dentry->d_inode);
597 rpci->private = private;
598 rpci->pipe = pipe;
599 fsnotify_create(dir, dentry);
600 return 0;
601 }
602
603 static int __rpc_rmdir(struct inode *dir, struct dentry *dentry)
604 {
605 int ret;
606
607 dget(dentry);
608 ret = simple_rmdir(dir, dentry);
609 d_delete(dentry);
610 dput(dentry);
611 return ret;
612 }
613
614 int rpc_rmdir(struct dentry *dentry)
615 {
616 struct dentry *parent;
617 struct inode *dir;
618 int error;
619
620 parent = dget_parent(dentry);
621 dir = parent->d_inode;
622 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
623 error = __rpc_rmdir(dir, dentry);
624 mutex_unlock(&dir->i_mutex);
625 dput(parent);
626 return error;
627 }
628 EXPORT_SYMBOL_GPL(rpc_rmdir);
629
630 static int __rpc_unlink(struct inode *dir, struct dentry *dentry)
631 {
632 int ret;
633
634 dget(dentry);
635 ret = simple_unlink(dir, dentry);
636 d_delete(dentry);
637 dput(dentry);
638 return ret;
639 }
640
641 static int __rpc_rmpipe(struct inode *dir, struct dentry *dentry)
642 {
643 struct inode *inode = dentry->d_inode;
644
645 rpc_close_pipes(inode);
646 return __rpc_unlink(dir, dentry);
647 }
648
649 static struct dentry *__rpc_lookup_create_exclusive(struct dentry *parent,
650 const char *name)
651 {
652 struct qstr q = QSTR_INIT(name, strlen(name));
653 struct dentry *dentry = d_hash_and_lookup(parent, &q);
654 if (!dentry) {
655 dentry = d_alloc(parent, &q);
656 if (!dentry)
657 return ERR_PTR(-ENOMEM);
658 }
659 if (dentry->d_inode == NULL)
660 return dentry;
661 dput(dentry);
662 return ERR_PTR(-EEXIST);
663 }
664
665 /*
666 * FIXME: This probably has races.
667 */
668 static void __rpc_depopulate(struct dentry *parent,
669 const struct rpc_filelist *files,
670 int start, int eof)
671 {
672 struct inode *dir = parent->d_inode;
673 struct dentry *dentry;
674 struct qstr name;
675 int i;
676
677 for (i = start; i < eof; i++) {
678 name.name = files[i].name;
679 name.len = strlen(files[i].name);
680 dentry = d_hash_and_lookup(parent, &name);
681
682 if (dentry == NULL)
683 continue;
684 if (dentry->d_inode == NULL)
685 goto next;
686 switch (dentry->d_inode->i_mode & S_IFMT) {
687 default:
688 BUG();
689 case S_IFREG:
690 __rpc_unlink(dir, dentry);
691 break;
692 case S_IFDIR:
693 __rpc_rmdir(dir, dentry);
694 }
695 next:
696 dput(dentry);
697 }
698 }
699
700 static void rpc_depopulate(struct dentry *parent,
701 const struct rpc_filelist *files,
702 int start, int eof)
703 {
704 struct inode *dir = parent->d_inode;
705
706 mutex_lock_nested(&dir->i_mutex, I_MUTEX_CHILD);
707 __rpc_depopulate(parent, files, start, eof);
708 mutex_unlock(&dir->i_mutex);
709 }
710
711 static int rpc_populate(struct dentry *parent,
712 const struct rpc_filelist *files,
713 int start, int eof,
714 void *private)
715 {
716 struct inode *dir = parent->d_inode;
717 struct dentry *dentry;
718 int i, err;
719
720 mutex_lock(&dir->i_mutex);
721 for (i = start; i < eof; i++) {
722 dentry = __rpc_lookup_create_exclusive(parent, files[i].name);
723 err = PTR_ERR(dentry);
724 if (IS_ERR(dentry))
725 goto out_bad;
726 switch (files[i].mode & S_IFMT) {
727 default:
728 BUG();
729 case S_IFREG:
730 err = __rpc_create(dir, dentry,
731 files[i].mode,
732 files[i].i_fop,
733 private);
734 break;
735 case S_IFDIR:
736 err = __rpc_mkdir(dir, dentry,
737 files[i].mode,
738 NULL,
739 private);
740 }
741 if (err != 0)
742 goto out_bad;
743 }
744 mutex_unlock(&dir->i_mutex);
745 return 0;
746 out_bad:
747 __rpc_depopulate(parent, files, start, eof);
748 mutex_unlock(&dir->i_mutex);
749 printk(KERN_WARNING "%s: %s failed to populate directory %pd\n",
750 __FILE__, __func__, parent);
751 return err;
752 }
753
754 static struct dentry *rpc_mkdir_populate(struct dentry *parent,
755 const char *name, umode_t mode, void *private,
756 int (*populate)(struct dentry *, void *), void *args_populate)
757 {
758 struct dentry *dentry;
759 struct inode *dir = parent->d_inode;
760 int error;
761
762 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
763 dentry = __rpc_lookup_create_exclusive(parent, name);
764 if (IS_ERR(dentry))
765 goto out;
766 error = __rpc_mkdir(dir, dentry, mode, NULL, private);
767 if (error != 0)
768 goto out_err;
769 if (populate != NULL) {
770 error = populate(dentry, args_populate);
771 if (error)
772 goto err_rmdir;
773 }
774 out:
775 mutex_unlock(&dir->i_mutex);
776 return dentry;
777 err_rmdir:
778 __rpc_rmdir(dir, dentry);
779 out_err:
780 dentry = ERR_PTR(error);
781 goto out;
782 }
783
784 static int rpc_rmdir_depopulate(struct dentry *dentry,
785 void (*depopulate)(struct dentry *))
786 {
787 struct dentry *parent;
788 struct inode *dir;
789 int error;
790
791 parent = dget_parent(dentry);
792 dir = parent->d_inode;
793 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
794 if (depopulate != NULL)
795 depopulate(dentry);
796 error = __rpc_rmdir(dir, dentry);
797 mutex_unlock(&dir->i_mutex);
798 dput(parent);
799 return error;
800 }
801
802 /**
803 * rpc_mkpipe - make an rpc_pipefs file for kernel<->userspace communication
804 * @parent: dentry of directory to create new "pipe" in
805 * @name: name of pipe
806 * @private: private data to associate with the pipe, for the caller's use
807 * @pipe: &rpc_pipe containing input parameters
808 *
809 * Data is made available for userspace to read by calls to
810 * rpc_queue_upcall(). The actual reads will result in calls to
811 * @ops->upcall, which will be called with the file pointer,
812 * message, and userspace buffer to copy to.
813 *
814 * Writes can come at any time, and do not necessarily have to be
815 * responses to upcalls. They will result in calls to @msg->downcall.
816 *
817 * The @private argument passed here will be available to all these methods
818 * from the file pointer, via RPC_I(file_inode(file))->private.
819 */
820 struct dentry *rpc_mkpipe_dentry(struct dentry *parent, const char *name,
821 void *private, struct rpc_pipe *pipe)
822 {
823 struct dentry *dentry;
824 struct inode *dir = parent->d_inode;
825 umode_t umode = S_IFIFO | S_IRUSR | S_IWUSR;
826 int err;
827
828 if (pipe->ops->upcall == NULL)
829 umode &= ~S_IRUGO;
830 if (pipe->ops->downcall == NULL)
831 umode &= ~S_IWUGO;
832
833 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
834 dentry = __rpc_lookup_create_exclusive(parent, name);
835 if (IS_ERR(dentry))
836 goto out;
837 err = __rpc_mkpipe_dentry(dir, dentry, umode, &rpc_pipe_fops,
838 private, pipe);
839 if (err)
840 goto out_err;
841 out:
842 mutex_unlock(&dir->i_mutex);
843 return dentry;
844 out_err:
845 dentry = ERR_PTR(err);
846 printk(KERN_WARNING "%s: %s() failed to create pipe %pd/%s (errno = %d)\n",
847 __FILE__, __func__, parent, name,
848 err);
849 goto out;
850 }
851 EXPORT_SYMBOL_GPL(rpc_mkpipe_dentry);
852
853 /**
854 * rpc_unlink - remove a pipe
855 * @dentry: dentry for the pipe, as returned from rpc_mkpipe
856 *
857 * After this call, lookups will no longer find the pipe, and any
858 * attempts to read or write using preexisting opens of the pipe will
859 * return -EPIPE.
860 */
861 int
862 rpc_unlink(struct dentry *dentry)
863 {
864 struct dentry *parent;
865 struct inode *dir;
866 int error = 0;
867
868 parent = dget_parent(dentry);
869 dir = parent->d_inode;
870 mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT);
871 error = __rpc_rmpipe(dir, dentry);
872 mutex_unlock(&dir->i_mutex);
873 dput(parent);
874 return error;
875 }
876 EXPORT_SYMBOL_GPL(rpc_unlink);
877
878 /**
879 * rpc_init_pipe_dir_head - initialise a struct rpc_pipe_dir_head
880 * @pdh: pointer to struct rpc_pipe_dir_head
881 */
882 void rpc_init_pipe_dir_head(struct rpc_pipe_dir_head *pdh)
883 {
884 INIT_LIST_HEAD(&pdh->pdh_entries);
885 pdh->pdh_dentry = NULL;
886 }
887 EXPORT_SYMBOL_GPL(rpc_init_pipe_dir_head);
888
889 /**
890 * rpc_init_pipe_dir_object - initialise a struct rpc_pipe_dir_object
891 * @pdo: pointer to struct rpc_pipe_dir_object
892 * @pdo_ops: pointer to const struct rpc_pipe_dir_object_ops
893 * @pdo_data: pointer to caller-defined data
894 */
895 void rpc_init_pipe_dir_object(struct rpc_pipe_dir_object *pdo,
896 const struct rpc_pipe_dir_object_ops *pdo_ops,
897 void *pdo_data)
898 {
899 INIT_LIST_HEAD(&pdo->pdo_head);
900 pdo->pdo_ops = pdo_ops;
901 pdo->pdo_data = pdo_data;
902 }
903 EXPORT_SYMBOL_GPL(rpc_init_pipe_dir_object);
904
905 static int
906 rpc_add_pipe_dir_object_locked(struct net *net,
907 struct rpc_pipe_dir_head *pdh,
908 struct rpc_pipe_dir_object *pdo)
909 {
910 int ret = 0;
911
912 if (pdh->pdh_dentry)
913 ret = pdo->pdo_ops->create(pdh->pdh_dentry, pdo);
914 if (ret == 0)
915 list_add_tail(&pdo->pdo_head, &pdh->pdh_entries);
916 return ret;
917 }
918
919 static void
920 rpc_remove_pipe_dir_object_locked(struct net *net,
921 struct rpc_pipe_dir_head *pdh,
922 struct rpc_pipe_dir_object *pdo)
923 {
924 if (pdh->pdh_dentry)
925 pdo->pdo_ops->destroy(pdh->pdh_dentry, pdo);
926 list_del_init(&pdo->pdo_head);
927 }
928
929 /**
930 * rpc_add_pipe_dir_object - associate a rpc_pipe_dir_object to a directory
931 * @net: pointer to struct net
932 * @pdh: pointer to struct rpc_pipe_dir_head
933 * @pdo: pointer to struct rpc_pipe_dir_object
934 *
935 */
936 int
937 rpc_add_pipe_dir_object(struct net *net,
938 struct rpc_pipe_dir_head *pdh,
939 struct rpc_pipe_dir_object *pdo)
940 {
941 int ret = 0;
942
943 if (list_empty(&pdo->pdo_head)) {
944 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
945
946 mutex_lock(&sn->pipefs_sb_lock);
947 ret = rpc_add_pipe_dir_object_locked(net, pdh, pdo);
948 mutex_unlock(&sn->pipefs_sb_lock);
949 }
950 return ret;
951 }
952 EXPORT_SYMBOL_GPL(rpc_add_pipe_dir_object);
953
954 /**
955 * rpc_remove_pipe_dir_object - remove a rpc_pipe_dir_object from a directory
956 * @net: pointer to struct net
957 * @pdh: pointer to struct rpc_pipe_dir_head
958 * @pdo: pointer to struct rpc_pipe_dir_object
959 *
960 */
961 void
962 rpc_remove_pipe_dir_object(struct net *net,
963 struct rpc_pipe_dir_head *pdh,
964 struct rpc_pipe_dir_object *pdo)
965 {
966 if (!list_empty(&pdo->pdo_head)) {
967 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
968
969 mutex_lock(&sn->pipefs_sb_lock);
970 rpc_remove_pipe_dir_object_locked(net, pdh, pdo);
971 mutex_unlock(&sn->pipefs_sb_lock);
972 }
973 }
974 EXPORT_SYMBOL_GPL(rpc_remove_pipe_dir_object);
975
976 /**
977 * rpc_find_or_alloc_pipe_dir_object
978 * @net: pointer to struct net
979 * @pdh: pointer to struct rpc_pipe_dir_head
980 * @match: match struct rpc_pipe_dir_object to data
981 * @alloc: allocate a new struct rpc_pipe_dir_object
982 * @data: user defined data for match() and alloc()
983 *
984 */
985 struct rpc_pipe_dir_object *
986 rpc_find_or_alloc_pipe_dir_object(struct net *net,
987 struct rpc_pipe_dir_head *pdh,
988 int (*match)(struct rpc_pipe_dir_object *, void *),
989 struct rpc_pipe_dir_object *(*alloc)(void *),
990 void *data)
991 {
992 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
993 struct rpc_pipe_dir_object *pdo;
994
995 mutex_lock(&sn->pipefs_sb_lock);
996 list_for_each_entry(pdo, &pdh->pdh_entries, pdo_head) {
997 if (!match(pdo, data))
998 continue;
999 goto out;
1000 }
1001 pdo = alloc(data);
1002 if (!pdo)
1003 goto out;
1004 rpc_add_pipe_dir_object_locked(net, pdh, pdo);
1005 out:
1006 mutex_unlock(&sn->pipefs_sb_lock);
1007 return pdo;
1008 }
1009 EXPORT_SYMBOL_GPL(rpc_find_or_alloc_pipe_dir_object);
1010
1011 static void
1012 rpc_create_pipe_dir_objects(struct rpc_pipe_dir_head *pdh)
1013 {
1014 struct rpc_pipe_dir_object *pdo;
1015 struct dentry *dir = pdh->pdh_dentry;
1016
1017 list_for_each_entry(pdo, &pdh->pdh_entries, pdo_head)
1018 pdo->pdo_ops->create(dir, pdo);
1019 }
1020
1021 static void
1022 rpc_destroy_pipe_dir_objects(struct rpc_pipe_dir_head *pdh)
1023 {
1024 struct rpc_pipe_dir_object *pdo;
1025 struct dentry *dir = pdh->pdh_dentry;
1026
1027 list_for_each_entry(pdo, &pdh->pdh_entries, pdo_head)
1028 pdo->pdo_ops->destroy(dir, pdo);
1029 }
1030
1031 enum {
1032 RPCAUTH_info,
1033 RPCAUTH_EOF
1034 };
1035
1036 static const struct rpc_filelist authfiles[] = {
1037 [RPCAUTH_info] = {
1038 .name = "info",
1039 .i_fop = &rpc_info_operations,
1040 .mode = S_IFREG | S_IRUSR,
1041 },
1042 };
1043
1044 static int rpc_clntdir_populate(struct dentry *dentry, void *private)
1045 {
1046 return rpc_populate(dentry,
1047 authfiles, RPCAUTH_info, RPCAUTH_EOF,
1048 private);
1049 }
1050
1051 static void rpc_clntdir_depopulate(struct dentry *dentry)
1052 {
1053 rpc_depopulate(dentry, authfiles, RPCAUTH_info, RPCAUTH_EOF);
1054 }
1055
1056 /**
1057 * rpc_create_client_dir - Create a new rpc_client directory in rpc_pipefs
1058 * @dentry: the parent of new directory
1059 * @name: the name of new directory
1060 * @rpc_client: rpc client to associate with this directory
1061 *
1062 * This creates a directory at the given @path associated with
1063 * @rpc_clnt, which will contain a file named "info" with some basic
1064 * information about the client, together with any "pipes" that may
1065 * later be created using rpc_mkpipe().
1066 */
1067 struct dentry *rpc_create_client_dir(struct dentry *dentry,
1068 const char *name,
1069 struct rpc_clnt *rpc_client)
1070 {
1071 struct dentry *ret;
1072
1073 ret = rpc_mkdir_populate(dentry, name, S_IRUGO | S_IXUGO, NULL,
1074 rpc_clntdir_populate, rpc_client);
1075 if (!IS_ERR(ret)) {
1076 rpc_client->cl_pipedir_objects.pdh_dentry = ret;
1077 rpc_create_pipe_dir_objects(&rpc_client->cl_pipedir_objects);
1078 }
1079 return ret;
1080 }
1081
1082 /**
1083 * rpc_remove_client_dir - Remove a directory created with rpc_create_client_dir()
1084 * @rpc_client: rpc_client for the pipe
1085 */
1086 int rpc_remove_client_dir(struct rpc_clnt *rpc_client)
1087 {
1088 struct dentry *dentry = rpc_client->cl_pipedir_objects.pdh_dentry;
1089
1090 if (dentry == NULL)
1091 return 0;
1092 rpc_destroy_pipe_dir_objects(&rpc_client->cl_pipedir_objects);
1093 rpc_client->cl_pipedir_objects.pdh_dentry = NULL;
1094 return rpc_rmdir_depopulate(dentry, rpc_clntdir_depopulate);
1095 }
1096
1097 static const struct rpc_filelist cache_pipefs_files[3] = {
1098 [0] = {
1099 .name = "channel",
1100 .i_fop = &cache_file_operations_pipefs,
1101 .mode = S_IFREG|S_IRUSR|S_IWUSR,
1102 },
1103 [1] = {
1104 .name = "content",
1105 .i_fop = &content_file_operations_pipefs,
1106 .mode = S_IFREG|S_IRUSR,
1107 },
1108 [2] = {
1109 .name = "flush",
1110 .i_fop = &cache_flush_operations_pipefs,
1111 .mode = S_IFREG|S_IRUSR|S_IWUSR,
1112 },
1113 };
1114
1115 static int rpc_cachedir_populate(struct dentry *dentry, void *private)
1116 {
1117 return rpc_populate(dentry,
1118 cache_pipefs_files, 0, 3,
1119 private);
1120 }
1121
1122 static void rpc_cachedir_depopulate(struct dentry *dentry)
1123 {
1124 rpc_depopulate(dentry, cache_pipefs_files, 0, 3);
1125 }
1126
1127 struct dentry *rpc_create_cache_dir(struct dentry *parent, const char *name,
1128 umode_t umode, struct cache_detail *cd)
1129 {
1130 return rpc_mkdir_populate(parent, name, umode, NULL,
1131 rpc_cachedir_populate, cd);
1132 }
1133
1134 void rpc_remove_cache_dir(struct dentry *dentry)
1135 {
1136 rpc_rmdir_depopulate(dentry, rpc_cachedir_depopulate);
1137 }
1138
1139 /*
1140 * populate the filesystem
1141 */
1142 static const struct super_operations s_ops = {
1143 .alloc_inode = rpc_alloc_inode,
1144 .destroy_inode = rpc_destroy_inode,
1145 .statfs = simple_statfs,
1146 };
1147
1148 #define RPCAUTH_GSSMAGIC 0x67596969
1149
1150 /*
1151 * We have a single directory with 1 node in it.
1152 */
1153 enum {
1154 RPCAUTH_lockd,
1155 RPCAUTH_mount,
1156 RPCAUTH_nfs,
1157 RPCAUTH_portmap,
1158 RPCAUTH_statd,
1159 RPCAUTH_nfsd4_cb,
1160 RPCAUTH_cache,
1161 RPCAUTH_nfsd,
1162 RPCAUTH_gssd,
1163 RPCAUTH_RootEOF
1164 };
1165
1166 static const struct rpc_filelist files[] = {
1167 [RPCAUTH_lockd] = {
1168 .name = "lockd",
1169 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1170 },
1171 [RPCAUTH_mount] = {
1172 .name = "mount",
1173 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1174 },
1175 [RPCAUTH_nfs] = {
1176 .name = "nfs",
1177 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1178 },
1179 [RPCAUTH_portmap] = {
1180 .name = "portmap",
1181 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1182 },
1183 [RPCAUTH_statd] = {
1184 .name = "statd",
1185 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1186 },
1187 [RPCAUTH_nfsd4_cb] = {
1188 .name = "nfsd4_cb",
1189 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1190 },
1191 [RPCAUTH_cache] = {
1192 .name = "cache",
1193 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1194 },
1195 [RPCAUTH_nfsd] = {
1196 .name = "nfsd",
1197 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1198 },
1199 [RPCAUTH_gssd] = {
1200 .name = "gssd",
1201 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1202 },
1203 };
1204
1205 /*
1206 * This call can be used only in RPC pipefs mount notification hooks.
1207 */
1208 struct dentry *rpc_d_lookup_sb(const struct super_block *sb,
1209 const unsigned char *dir_name)
1210 {
1211 struct qstr dir = QSTR_INIT(dir_name, strlen(dir_name));
1212 return d_hash_and_lookup(sb->s_root, &dir);
1213 }
1214 EXPORT_SYMBOL_GPL(rpc_d_lookup_sb);
1215
1216 int rpc_pipefs_init_net(struct net *net)
1217 {
1218 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1219
1220 sn->gssd_dummy = rpc_mkpipe_data(&gssd_dummy_pipe_ops, 0);
1221 if (IS_ERR(sn->gssd_dummy))
1222 return PTR_ERR(sn->gssd_dummy);
1223
1224 mutex_init(&sn->pipefs_sb_lock);
1225 sn->gssd_running = 1;
1226 sn->pipe_version = -1;
1227 return 0;
1228 }
1229
1230 void rpc_pipefs_exit_net(struct net *net)
1231 {
1232 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1233
1234 rpc_destroy_pipe_data(sn->gssd_dummy);
1235 }
1236
1237 /*
1238 * This call will be used for per network namespace operations calls.
1239 * Note: Function will be returned with pipefs_sb_lock taken if superblock was
1240 * found. This lock have to be released by rpc_put_sb_net() when all operations
1241 * will be completed.
1242 */
1243 struct super_block *rpc_get_sb_net(const struct net *net)
1244 {
1245 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1246
1247 mutex_lock(&sn->pipefs_sb_lock);
1248 if (sn->pipefs_sb)
1249 return sn->pipefs_sb;
1250 mutex_unlock(&sn->pipefs_sb_lock);
1251 return NULL;
1252 }
1253 EXPORT_SYMBOL_GPL(rpc_get_sb_net);
1254
1255 void rpc_put_sb_net(const struct net *net)
1256 {
1257 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1258
1259 WARN_ON(sn->pipefs_sb == NULL);
1260 mutex_unlock(&sn->pipefs_sb_lock);
1261 }
1262 EXPORT_SYMBOL_GPL(rpc_put_sb_net);
1263
1264 static const struct rpc_filelist gssd_dummy_clnt_dir[] = {
1265 [0] = {
1266 .name = "clntXX",
1267 .mode = S_IFDIR | S_IRUGO | S_IXUGO,
1268 },
1269 };
1270
1271 static ssize_t
1272 dummy_downcall(struct file *filp, const char __user *src, size_t len)
1273 {
1274 return -EINVAL;
1275 }
1276
1277 static const struct rpc_pipe_ops gssd_dummy_pipe_ops = {
1278 .upcall = rpc_pipe_generic_upcall,
1279 .downcall = dummy_downcall,
1280 };
1281
1282 /**
1283 * rpc_gssd_dummy_populate - create a dummy gssd pipe
1284 * @root: root of the rpc_pipefs filesystem
1285 * @pipe_data: pipe data created when netns is initialized
1286 *
1287 * Create a dummy set of directories and a pipe that gssd can hold open to
1288 * indicate that it is up and running.
1289 */
1290 static struct dentry *
1291 rpc_gssd_dummy_populate(struct dentry *root, struct rpc_pipe *pipe_data)
1292 {
1293 int ret = 0;
1294 struct dentry *gssd_dentry;
1295 struct dentry *clnt_dentry = NULL;
1296 struct dentry *pipe_dentry = NULL;
1297 struct qstr q = QSTR_INIT(files[RPCAUTH_gssd].name,
1298 strlen(files[RPCAUTH_gssd].name));
1299
1300 /* We should never get this far if "gssd" doesn't exist */
1301 gssd_dentry = d_hash_and_lookup(root, &q);
1302 if (!gssd_dentry)
1303 return ERR_PTR(-ENOENT);
1304
1305 ret = rpc_populate(gssd_dentry, gssd_dummy_clnt_dir, 0, 1, NULL);
1306 if (ret) {
1307 pipe_dentry = ERR_PTR(ret);
1308 goto out;
1309 }
1310
1311 q.name = gssd_dummy_clnt_dir[0].name;
1312 q.len = strlen(gssd_dummy_clnt_dir[0].name);
1313 clnt_dentry = d_hash_and_lookup(gssd_dentry, &q);
1314 if (!clnt_dentry) {
1315 pipe_dentry = ERR_PTR(-ENOENT);
1316 goto out;
1317 }
1318
1319 pipe_dentry = rpc_mkpipe_dentry(clnt_dentry, "gssd", NULL, pipe_data);
1320 out:
1321 dput(clnt_dentry);
1322 dput(gssd_dentry);
1323 return pipe_dentry;
1324 }
1325
1326 static int
1327 rpc_fill_super(struct super_block *sb, void *data, int silent)
1328 {
1329 struct inode *inode;
1330 struct dentry *root, *gssd_dentry;
1331 struct net *net = data;
1332 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1333 int err;
1334
1335 sb->s_blocksize = PAGE_CACHE_SIZE;
1336 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
1337 sb->s_magic = RPCAUTH_GSSMAGIC;
1338 sb->s_op = &s_ops;
1339 sb->s_d_op = &simple_dentry_operations;
1340 sb->s_time_gran = 1;
1341
1342 inode = rpc_get_inode(sb, S_IFDIR | S_IRUGO | S_IXUGO);
1343 sb->s_root = root = d_make_root(inode);
1344 if (!root)
1345 return -ENOMEM;
1346 if (rpc_populate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF, NULL))
1347 return -ENOMEM;
1348
1349 gssd_dentry = rpc_gssd_dummy_populate(root, sn->gssd_dummy);
1350 if (IS_ERR(gssd_dentry)) {
1351 __rpc_depopulate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF);
1352 return PTR_ERR(gssd_dentry);
1353 }
1354
1355 dprintk("RPC: sending pipefs MOUNT notification for net %p%s\n",
1356 net, NET_NAME(net));
1357 mutex_lock(&sn->pipefs_sb_lock);
1358 sn->pipefs_sb = sb;
1359 err = blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1360 RPC_PIPEFS_MOUNT,
1361 sb);
1362 if (err)
1363 goto err_depopulate;
1364 sb->s_fs_info = get_net(net);
1365 mutex_unlock(&sn->pipefs_sb_lock);
1366 return 0;
1367
1368 err_depopulate:
1369 dput(gssd_dentry);
1370 blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1371 RPC_PIPEFS_UMOUNT,
1372 sb);
1373 sn->pipefs_sb = NULL;
1374 __rpc_depopulate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF);
1375 mutex_unlock(&sn->pipefs_sb_lock);
1376 return err;
1377 }
1378
1379 static struct dentry *
1380 rpc_mount(struct file_system_type *fs_type,
1381 int flags, const char *dev_name, void *data)
1382 {
1383 return mount_ns(fs_type, flags, current->nsproxy->net_ns, rpc_fill_super);
1384 }
1385
1386 static void rpc_kill_sb(struct super_block *sb)
1387 {
1388 struct net *net = sb->s_fs_info;
1389 struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
1390
1391 mutex_lock(&sn->pipefs_sb_lock);
1392 if (sn->pipefs_sb != sb) {
1393 mutex_unlock(&sn->pipefs_sb_lock);
1394 goto out;
1395 }
1396 sn->pipefs_sb = NULL;
1397 dprintk("RPC: sending pipefs UMOUNT notification for net %p%s\n",
1398 net, NET_NAME(net));
1399 blocking_notifier_call_chain(&rpc_pipefs_notifier_list,
1400 RPC_PIPEFS_UMOUNT,
1401 sb);
1402 mutex_unlock(&sn->pipefs_sb_lock);
1403 put_net(net);
1404 out:
1405 kill_litter_super(sb);
1406 }
1407
1408 static struct file_system_type rpc_pipe_fs_type = {
1409 .owner = THIS_MODULE,
1410 .name = "rpc_pipefs",
1411 .mount = rpc_mount,
1412 .kill_sb = rpc_kill_sb,
1413 };
1414 MODULE_ALIAS_FS("rpc_pipefs");
1415 MODULE_ALIAS("rpc_pipefs");
1416
1417 static void
1418 init_once(void *foo)
1419 {
1420 struct rpc_inode *rpci = (struct rpc_inode *) foo;
1421
1422 inode_init_once(&rpci->vfs_inode);
1423 rpci->private = NULL;
1424 rpci->pipe = NULL;
1425 init_waitqueue_head(&rpci->waitq);
1426 }
1427
1428 int register_rpc_pipefs(void)
1429 {
1430 int err;
1431
1432 rpc_inode_cachep = kmem_cache_create("rpc_inode_cache",
1433 sizeof(struct rpc_inode),
1434 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT|
1435 SLAB_MEM_SPREAD),
1436 init_once);
1437 if (!rpc_inode_cachep)
1438 return -ENOMEM;
1439 err = rpc_clients_notifier_register();
1440 if (err)
1441 goto err_notifier;
1442 err = register_filesystem(&rpc_pipe_fs_type);
1443 if (err)
1444 goto err_register;
1445 return 0;
1446
1447 err_register:
1448 rpc_clients_notifier_unregister();
1449 err_notifier:
1450 kmem_cache_destroy(rpc_inode_cachep);
1451 return err;
1452 }
1453
1454 void unregister_rpc_pipefs(void)
1455 {
1456 rpc_clients_notifier_unregister();
1457 kmem_cache_destroy(rpc_inode_cachep);
1458 unregister_filesystem(&rpc_pipe_fs_type);
1459 }
Linux kernel - Deliverables
This page took 0.062752 seconds and 5 git commands to generate.