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