Root/
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 | |
20 | #include <asm/ioctls.h> |
21 | #include <linux/fs.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 | |
31 | static struct vfsmount *rpc_mount __read_mostly; |
32 | static int rpc_mount_count; |
33 | |
34 | static struct file_system_type rpc_pipe_fs_type; |
35 | |
36 | |
37 | static struct kmem_cache *rpc_inode_cachep __read_mostly; |
38 | |
39 | #define RPC_UPCALL_TIMEOUT (30*HZ) |
40 | |
41 | static void rpc_purge_list(struct rpc_inode *rpci, struct list_head *head, |
42 | void (*destroy_msg)(struct rpc_pipe_msg *), int err) |
43 | { |
44 | struct rpc_pipe_msg *msg; |
45 | |
46 | if (list_empty(head)) |
47 | return; |
48 | do { |
49 | msg = list_entry(head->next, struct rpc_pipe_msg, list); |
50 | list_del(&msg->list); |
51 | msg->errno = err; |
52 | destroy_msg(msg); |
53 | } while (!list_empty(head)); |
54 | wake_up(&rpci->waitq); |
55 | } |
56 | |
57 | static void |
58 | rpc_timeout_upcall_queue(struct work_struct *work) |
59 | { |
60 | LIST_HEAD(free_list); |
61 | struct rpc_inode *rpci = |
62 | container_of(work, struct rpc_inode, queue_timeout.work); |
63 | struct inode *inode = &rpci->vfs_inode; |
64 | void (*destroy_msg)(struct rpc_pipe_msg *); |
65 | |
66 | spin_lock(&inode->i_lock); |
67 | if (rpci->ops == NULL) { |
68 | spin_unlock(&inode->i_lock); |
69 | return; |
70 | } |
71 | destroy_msg = rpci->ops->destroy_msg; |
72 | if (rpci->nreaders == 0) { |
73 | list_splice_init(&rpci->pipe, &free_list); |
74 | rpci->pipelen = 0; |
75 | } |
76 | spin_unlock(&inode->i_lock); |
77 | rpc_purge_list(rpci, &free_list, destroy_msg, -ETIMEDOUT); |
78 | } |
79 | |
80 | /** |
81 | * rpc_queue_upcall - queue an upcall message to userspace |
82 | * @inode: inode of upcall pipe on which to queue given message |
83 | * @msg: message to queue |
84 | * |
85 | * Call with an @inode created by rpc_mkpipe() to queue an upcall. |
86 | * A userspace process may then later read the upcall by performing a |
87 | * read on an open file for this inode. It is up to the caller to |
88 | * initialize the fields of @msg (other than @msg->list) appropriately. |
89 | */ |
90 | int |
91 | rpc_queue_upcall(struct inode *inode, struct rpc_pipe_msg *msg) |
92 | { |
93 | struct rpc_inode *rpci = RPC_I(inode); |
94 | int res = -EPIPE; |
95 | |
96 | spin_lock(&inode->i_lock); |
97 | if (rpci->ops == NULL) |
98 | goto out; |
99 | if (rpci->nreaders) { |
100 | list_add_tail(&msg->list, &rpci->pipe); |
101 | rpci->pipelen += msg->len; |
102 | res = 0; |
103 | } else if (rpci->flags & RPC_PIPE_WAIT_FOR_OPEN) { |
104 | if (list_empty(&rpci->pipe)) |
105 | queue_delayed_work(rpciod_workqueue, |
106 | &rpci->queue_timeout, |
107 | RPC_UPCALL_TIMEOUT); |
108 | list_add_tail(&msg->list, &rpci->pipe); |
109 | rpci->pipelen += msg->len; |
110 | res = 0; |
111 | } |
112 | out: |
113 | spin_unlock(&inode->i_lock); |
114 | wake_up(&rpci->waitq); |
115 | return res; |
116 | } |
117 | EXPORT_SYMBOL_GPL(rpc_queue_upcall); |
118 | |
119 | static inline void |
120 | rpc_inode_setowner(struct inode *inode, void *private) |
121 | { |
122 | RPC_I(inode)->private = private; |
123 | } |
124 | |
125 | static void |
126 | rpc_close_pipes(struct inode *inode) |
127 | { |
128 | struct rpc_inode *rpci = RPC_I(inode); |
129 | const struct rpc_pipe_ops *ops; |
130 | int need_release; |
131 | |
132 | mutex_lock(&inode->i_mutex); |
133 | ops = rpci->ops; |
134 | if (ops != NULL) { |
135 | LIST_HEAD(free_list); |
136 | spin_lock(&inode->i_lock); |
137 | need_release = rpci->nreaders != 0 || rpci->nwriters != 0; |
138 | rpci->nreaders = 0; |
139 | list_splice_init(&rpci->in_upcall, &free_list); |
140 | list_splice_init(&rpci->pipe, &free_list); |
141 | rpci->pipelen = 0; |
142 | rpci->ops = NULL; |
143 | spin_unlock(&inode->i_lock); |
144 | rpc_purge_list(rpci, &free_list, ops->destroy_msg, -EPIPE); |
145 | rpci->nwriters = 0; |
146 | if (need_release && ops->release_pipe) |
147 | ops->release_pipe(inode); |
148 | cancel_delayed_work_sync(&rpci->queue_timeout); |
149 | } |
150 | rpc_inode_setowner(inode, NULL); |
151 | mutex_unlock(&inode->i_mutex); |
152 | } |
153 | |
154 | static struct inode * |
155 | rpc_alloc_inode(struct super_block *sb) |
156 | { |
157 | struct rpc_inode *rpci; |
158 | rpci = (struct rpc_inode *)kmem_cache_alloc(rpc_inode_cachep, GFP_KERNEL); |
159 | if (!rpci) |
160 | return NULL; |
161 | return &rpci->vfs_inode; |
162 | } |
163 | |
164 | static void |
165 | rpc_destroy_inode(struct inode *inode) |
166 | { |
167 | kmem_cache_free(rpc_inode_cachep, RPC_I(inode)); |
168 | } |
169 | |
170 | static int |
171 | rpc_pipe_open(struct inode *inode, struct file *filp) |
172 | { |
173 | struct rpc_inode *rpci = RPC_I(inode); |
174 | int first_open; |
175 | int res = -ENXIO; |
176 | |
177 | mutex_lock(&inode->i_mutex); |
178 | if (rpci->ops == NULL) |
179 | goto out; |
180 | first_open = rpci->nreaders == 0 && rpci->nwriters == 0; |
181 | if (first_open && rpci->ops->open_pipe) { |
182 | res = rpci->ops->open_pipe(inode); |
183 | if (res) |
184 | goto out; |
185 | } |
186 | if (filp->f_mode & FMODE_READ) |
187 | rpci->nreaders++; |
188 | if (filp->f_mode & FMODE_WRITE) |
189 | rpci->nwriters++; |
190 | res = 0; |
191 | out: |
192 | mutex_unlock(&inode->i_mutex); |
193 | return res; |
194 | } |
195 | |
196 | static int |
197 | rpc_pipe_release(struct inode *inode, struct file *filp) |
198 | { |
199 | struct rpc_inode *rpci = RPC_I(inode); |
200 | struct rpc_pipe_msg *msg; |
201 | int last_close; |
202 | |
203 | mutex_lock(&inode->i_mutex); |
204 | if (rpci->ops == NULL) |
205 | goto out; |
206 | msg = (struct rpc_pipe_msg *)filp->private_data; |
207 | if (msg != NULL) { |
208 | spin_lock(&inode->i_lock); |
209 | msg->errno = -EAGAIN; |
210 | list_del(&msg->list); |
211 | spin_unlock(&inode->i_lock); |
212 | rpci->ops->destroy_msg(msg); |
213 | } |
214 | if (filp->f_mode & FMODE_WRITE) |
215 | rpci->nwriters --; |
216 | if (filp->f_mode & FMODE_READ) { |
217 | rpci->nreaders --; |
218 | if (rpci->nreaders == 0) { |
219 | LIST_HEAD(free_list); |
220 | spin_lock(&inode->i_lock); |
221 | list_splice_init(&rpci->pipe, &free_list); |
222 | rpci->pipelen = 0; |
223 | spin_unlock(&inode->i_lock); |
224 | rpc_purge_list(rpci, &free_list, |
225 | rpci->ops->destroy_msg, -EAGAIN); |
226 | } |
227 | } |
228 | last_close = rpci->nwriters == 0 && rpci->nreaders == 0; |
229 | if (last_close && rpci->ops->release_pipe) |
230 | rpci->ops->release_pipe(inode); |
231 | out: |
232 | mutex_unlock(&inode->i_mutex); |
233 | return 0; |
234 | } |
235 | |
236 | static ssize_t |
237 | rpc_pipe_read(struct file *filp, char __user *buf, size_t len, loff_t *offset) |
238 | { |
239 | struct inode *inode = filp->f_path.dentry->d_inode; |
240 | struct rpc_inode *rpci = RPC_I(inode); |
241 | struct rpc_pipe_msg *msg; |
242 | int res = 0; |
243 | |
244 | mutex_lock(&inode->i_mutex); |
245 | if (rpci->ops == NULL) { |
246 | res = -EPIPE; |
247 | goto out_unlock; |
248 | } |
249 | msg = filp->private_data; |
250 | if (msg == NULL) { |
251 | spin_lock(&inode->i_lock); |
252 | if (!list_empty(&rpci->pipe)) { |
253 | msg = list_entry(rpci->pipe.next, |
254 | struct rpc_pipe_msg, |
255 | list); |
256 | list_move(&msg->list, &rpci->in_upcall); |
257 | rpci->pipelen -= msg->len; |
258 | filp->private_data = msg; |
259 | msg->copied = 0; |
260 | } |
261 | spin_unlock(&inode->i_lock); |
262 | if (msg == NULL) |
263 | goto out_unlock; |
264 | } |
265 | /* NOTE: it is up to the callback to update msg->copied */ |
266 | res = rpci->ops->upcall(filp, msg, buf, len); |
267 | if (res < 0 || msg->len == msg->copied) { |
268 | filp->private_data = NULL; |
269 | spin_lock(&inode->i_lock); |
270 | list_del(&msg->list); |
271 | spin_unlock(&inode->i_lock); |
272 | rpci->ops->destroy_msg(msg); |
273 | } |
274 | out_unlock: |
275 | mutex_unlock(&inode->i_mutex); |
276 | return res; |
277 | } |
278 | |
279 | static ssize_t |
280 | rpc_pipe_write(struct file *filp, const char __user *buf, size_t len, loff_t *offset) |
281 | { |
282 | struct inode *inode = filp->f_path.dentry->d_inode; |
283 | struct rpc_inode *rpci = RPC_I(inode); |
284 | int res; |
285 | |
286 | mutex_lock(&inode->i_mutex); |
287 | res = -EPIPE; |
288 | if (rpci->ops != NULL) |
289 | res = rpci->ops->downcall(filp, buf, len); |
290 | mutex_unlock(&inode->i_mutex); |
291 | return res; |
292 | } |
293 | |
294 | static unsigned int |
295 | rpc_pipe_poll(struct file *filp, struct poll_table_struct *wait) |
296 | { |
297 | struct rpc_inode *rpci; |
298 | unsigned int mask = 0; |
299 | |
300 | rpci = RPC_I(filp->f_path.dentry->d_inode); |
301 | poll_wait(filp, &rpci->waitq, wait); |
302 | |
303 | mask = POLLOUT | POLLWRNORM; |
304 | if (rpci->ops == NULL) |
305 | mask |= POLLERR | POLLHUP; |
306 | if (filp->private_data || !list_empty(&rpci->pipe)) |
307 | mask |= POLLIN | POLLRDNORM; |
308 | return mask; |
309 | } |
310 | |
311 | static int |
312 | rpc_pipe_ioctl(struct inode *ino, struct file *filp, |
313 | unsigned int cmd, unsigned long arg) |
314 | { |
315 | struct rpc_inode *rpci = RPC_I(filp->f_path.dentry->d_inode); |
316 | int len; |
317 | |
318 | switch (cmd) { |
319 | case FIONREAD: |
320 | if (rpci->ops == NULL) |
321 | return -EPIPE; |
322 | len = rpci->pipelen; |
323 | if (filp->private_data) { |
324 | struct rpc_pipe_msg *msg; |
325 | msg = (struct rpc_pipe_msg *)filp->private_data; |
326 | len += msg->len - msg->copied; |
327 | } |
328 | return put_user(len, (int __user *)arg); |
329 | default: |
330 | return -EINVAL; |
331 | } |
332 | } |
333 | |
334 | static const struct file_operations rpc_pipe_fops = { |
335 | .owner = THIS_MODULE, |
336 | .llseek = no_llseek, |
337 | .read = rpc_pipe_read, |
338 | .write = rpc_pipe_write, |
339 | .poll = rpc_pipe_poll, |
340 | .ioctl = rpc_pipe_ioctl, |
341 | .open = rpc_pipe_open, |
342 | .release = rpc_pipe_release, |
343 | }; |
344 | |
345 | static int |
346 | rpc_show_info(struct seq_file *m, void *v) |
347 | { |
348 | struct rpc_clnt *clnt = m->private; |
349 | |
350 | seq_printf(m, "RPC server: %s\n", clnt->cl_server); |
351 | seq_printf(m, "service: %s (%d) version %d\n", clnt->cl_protname, |
352 | clnt->cl_prog, clnt->cl_vers); |
353 | seq_printf(m, "address: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR)); |
354 | seq_printf(m, "protocol: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_PROTO)); |
355 | seq_printf(m, "port: %s\n", rpc_peeraddr2str(clnt, RPC_DISPLAY_PORT)); |
356 | return 0; |
357 | } |
358 | |
359 | static int |
360 | rpc_info_open(struct inode *inode, struct file *file) |
361 | { |
362 | struct rpc_clnt *clnt; |
363 | int ret = single_open(file, rpc_show_info, NULL); |
364 | |
365 | if (!ret) { |
366 | struct seq_file *m = file->private_data; |
367 | mutex_lock(&inode->i_mutex); |
368 | clnt = RPC_I(inode)->private; |
369 | if (clnt) { |
370 | kref_get(&clnt->cl_kref); |
371 | m->private = clnt; |
372 | } else { |
373 | single_release(inode, file); |
374 | ret = -EINVAL; |
375 | } |
376 | mutex_unlock(&inode->i_mutex); |
377 | } |
378 | return ret; |
379 | } |
380 | |
381 | static int |
382 | rpc_info_release(struct inode *inode, struct file *file) |
383 | { |
384 | struct seq_file *m = file->private_data; |
385 | struct rpc_clnt *clnt = (struct rpc_clnt *)m->private; |
386 | |
387 | if (clnt) |
388 | rpc_release_client(clnt); |
389 | return single_release(inode, file); |
390 | } |
391 | |
392 | static const struct file_operations rpc_info_operations = { |
393 | .owner = THIS_MODULE, |
394 | .open = rpc_info_open, |
395 | .read = seq_read, |
396 | .llseek = seq_lseek, |
397 | .release = rpc_info_release, |
398 | }; |
399 | |
400 | |
401 | /* |
402 | * Description of fs contents. |
403 | */ |
404 | struct rpc_filelist { |
405 | const char *name; |
406 | const struct file_operations *i_fop; |
407 | umode_t mode; |
408 | }; |
409 | |
410 | struct vfsmount *rpc_get_mount(void) |
411 | { |
412 | int err; |
413 | |
414 | err = simple_pin_fs(&rpc_pipe_fs_type, &rpc_mount, &rpc_mount_count); |
415 | if (err != 0) |
416 | return ERR_PTR(err); |
417 | return rpc_mount; |
418 | } |
419 | EXPORT_SYMBOL_GPL(rpc_get_mount); |
420 | |
421 | void rpc_put_mount(void) |
422 | { |
423 | simple_release_fs(&rpc_mount, &rpc_mount_count); |
424 | } |
425 | EXPORT_SYMBOL_GPL(rpc_put_mount); |
426 | |
427 | static int rpc_delete_dentry(struct dentry *dentry) |
428 | { |
429 | return 1; |
430 | } |
431 | |
432 | static const struct dentry_operations rpc_dentry_operations = { |
433 | .d_delete = rpc_delete_dentry, |
434 | }; |
435 | |
436 | static struct inode * |
437 | rpc_get_inode(struct super_block *sb, umode_t mode) |
438 | { |
439 | struct inode *inode = new_inode(sb); |
440 | if (!inode) |
441 | return NULL; |
442 | inode->i_mode = mode; |
443 | inode->i_atime = inode->i_mtime = inode->i_ctime = CURRENT_TIME; |
444 | switch(mode & S_IFMT) { |
445 | case S_IFDIR: |
446 | inode->i_fop = &simple_dir_operations; |
447 | inode->i_op = &simple_dir_inode_operations; |
448 | inc_nlink(inode); |
449 | default: |
450 | break; |
451 | } |
452 | return inode; |
453 | } |
454 | |
455 | static int __rpc_create_common(struct inode *dir, struct dentry *dentry, |
456 | umode_t mode, |
457 | const struct file_operations *i_fop, |
458 | void *private) |
459 | { |
460 | struct inode *inode; |
461 | |
462 | BUG_ON(!d_unhashed(dentry)); |
463 | inode = rpc_get_inode(dir->i_sb, mode); |
464 | if (!inode) |
465 | goto out_err; |
466 | inode->i_ino = iunique(dir->i_sb, 100); |
467 | if (i_fop) |
468 | inode->i_fop = i_fop; |
469 | if (private) |
470 | rpc_inode_setowner(inode, private); |
471 | d_add(dentry, inode); |
472 | return 0; |
473 | out_err: |
474 | printk(KERN_WARNING "%s: %s failed to allocate inode for dentry %s\n", |
475 | __FILE__, __func__, dentry->d_name.name); |
476 | dput(dentry); |
477 | return -ENOMEM; |
478 | } |
479 | |
480 | static int __rpc_create(struct inode *dir, struct dentry *dentry, |
481 | umode_t mode, |
482 | const struct file_operations *i_fop, |
483 | void *private) |
484 | { |
485 | int err; |
486 | |
487 | err = __rpc_create_common(dir, dentry, S_IFREG | mode, i_fop, private); |
488 | if (err) |
489 | return err; |
490 | fsnotify_create(dir, dentry); |
491 | return 0; |
492 | } |
493 | |
494 | static int __rpc_mkdir(struct inode *dir, struct dentry *dentry, |
495 | umode_t mode, |
496 | const struct file_operations *i_fop, |
497 | void *private) |
498 | { |
499 | int err; |
500 | |
501 | err = __rpc_create_common(dir, dentry, S_IFDIR | mode, i_fop, private); |
502 | if (err) |
503 | return err; |
504 | inc_nlink(dir); |
505 | fsnotify_mkdir(dir, dentry); |
506 | return 0; |
507 | } |
508 | |
509 | static int __rpc_mkpipe(struct inode *dir, struct dentry *dentry, |
510 | umode_t mode, |
511 | const struct file_operations *i_fop, |
512 | void *private, |
513 | const struct rpc_pipe_ops *ops, |
514 | int flags) |
515 | { |
516 | struct rpc_inode *rpci; |
517 | int err; |
518 | |
519 | err = __rpc_create_common(dir, dentry, S_IFIFO | mode, i_fop, private); |
520 | if (err) |
521 | return err; |
522 | rpci = RPC_I(dentry->d_inode); |
523 | rpci->nkern_readwriters = 1; |
524 | rpci->private = private; |
525 | rpci->flags = flags; |
526 | rpci->ops = ops; |
527 | fsnotify_create(dir, dentry); |
528 | return 0; |
529 | } |
530 | |
531 | static int __rpc_rmdir(struct inode *dir, struct dentry *dentry) |
532 | { |
533 | int ret; |
534 | |
535 | dget(dentry); |
536 | ret = simple_rmdir(dir, dentry); |
537 | d_delete(dentry); |
538 | dput(dentry); |
539 | return ret; |
540 | } |
541 | |
542 | static int __rpc_unlink(struct inode *dir, struct dentry *dentry) |
543 | { |
544 | int ret; |
545 | |
546 | dget(dentry); |
547 | ret = simple_unlink(dir, dentry); |
548 | d_delete(dentry); |
549 | dput(dentry); |
550 | return ret; |
551 | } |
552 | |
553 | static int __rpc_rmpipe(struct inode *dir, struct dentry *dentry) |
554 | { |
555 | struct inode *inode = dentry->d_inode; |
556 | struct rpc_inode *rpci = RPC_I(inode); |
557 | |
558 | rpci->nkern_readwriters--; |
559 | if (rpci->nkern_readwriters != 0) |
560 | return 0; |
561 | rpc_close_pipes(inode); |
562 | return __rpc_unlink(dir, dentry); |
563 | } |
564 | |
565 | static struct dentry *__rpc_lookup_create(struct dentry *parent, |
566 | struct qstr *name) |
567 | { |
568 | struct dentry *dentry; |
569 | |
570 | dentry = d_lookup(parent, name); |
571 | if (!dentry) { |
572 | dentry = d_alloc(parent, name); |
573 | if (!dentry) { |
574 | dentry = ERR_PTR(-ENOMEM); |
575 | goto out_err; |
576 | } |
577 | } |
578 | if (!dentry->d_inode) |
579 | dentry->d_op = &rpc_dentry_operations; |
580 | out_err: |
581 | return dentry; |
582 | } |
583 | |
584 | static struct dentry *__rpc_lookup_create_exclusive(struct dentry *parent, |
585 | struct qstr *name) |
586 | { |
587 | struct dentry *dentry; |
588 | |
589 | dentry = __rpc_lookup_create(parent, name); |
590 | if (IS_ERR(dentry)) |
591 | return dentry; |
592 | if (dentry->d_inode == NULL) |
593 | return dentry; |
594 | dput(dentry); |
595 | return ERR_PTR(-EEXIST); |
596 | } |
597 | |
598 | /* |
599 | * FIXME: This probably has races. |
600 | */ |
601 | static void __rpc_depopulate(struct dentry *parent, |
602 | const struct rpc_filelist *files, |
603 | int start, int eof) |
604 | { |
605 | struct inode *dir = parent->d_inode; |
606 | struct dentry *dentry; |
607 | struct qstr name; |
608 | int i; |
609 | |
610 | for (i = start; i < eof; i++) { |
611 | name.name = files[i].name; |
612 | name.len = strlen(files[i].name); |
613 | name.hash = full_name_hash(name.name, name.len); |
614 | dentry = d_lookup(parent, &name); |
615 | |
616 | if (dentry == NULL) |
617 | continue; |
618 | if (dentry->d_inode == NULL) |
619 | goto next; |
620 | switch (dentry->d_inode->i_mode & S_IFMT) { |
621 | default: |
622 | BUG(); |
623 | case S_IFREG: |
624 | __rpc_unlink(dir, dentry); |
625 | break; |
626 | case S_IFDIR: |
627 | __rpc_rmdir(dir, dentry); |
628 | } |
629 | next: |
630 | dput(dentry); |
631 | } |
632 | } |
633 | |
634 | static void rpc_depopulate(struct dentry *parent, |
635 | const struct rpc_filelist *files, |
636 | int start, int eof) |
637 | { |
638 | struct inode *dir = parent->d_inode; |
639 | |
640 | mutex_lock_nested(&dir->i_mutex, I_MUTEX_CHILD); |
641 | __rpc_depopulate(parent, files, start, eof); |
642 | mutex_unlock(&dir->i_mutex); |
643 | } |
644 | |
645 | static int rpc_populate(struct dentry *parent, |
646 | const struct rpc_filelist *files, |
647 | int start, int eof, |
648 | void *private) |
649 | { |
650 | struct inode *dir = parent->d_inode; |
651 | struct dentry *dentry; |
652 | int i, err; |
653 | |
654 | mutex_lock(&dir->i_mutex); |
655 | for (i = start; i < eof; i++) { |
656 | struct qstr q; |
657 | |
658 | q.name = files[i].name; |
659 | q.len = strlen(files[i].name); |
660 | q.hash = full_name_hash(q.name, q.len); |
661 | dentry = __rpc_lookup_create_exclusive(parent, &q); |
662 | err = PTR_ERR(dentry); |
663 | if (IS_ERR(dentry)) |
664 | goto out_bad; |
665 | switch (files[i].mode & S_IFMT) { |
666 | default: |
667 | BUG(); |
668 | case S_IFREG: |
669 | err = __rpc_create(dir, dentry, |
670 | files[i].mode, |
671 | files[i].i_fop, |
672 | private); |
673 | break; |
674 | case S_IFDIR: |
675 | err = __rpc_mkdir(dir, dentry, |
676 | files[i].mode, |
677 | NULL, |
678 | private); |
679 | } |
680 | if (err != 0) |
681 | goto out_bad; |
682 | } |
683 | mutex_unlock(&dir->i_mutex); |
684 | return 0; |
685 | out_bad: |
686 | __rpc_depopulate(parent, files, start, eof); |
687 | mutex_unlock(&dir->i_mutex); |
688 | printk(KERN_WARNING "%s: %s failed to populate directory %s\n", |
689 | __FILE__, __func__, parent->d_name.name); |
690 | return err; |
691 | } |
692 | |
693 | static struct dentry *rpc_mkdir_populate(struct dentry *parent, |
694 | struct qstr *name, umode_t mode, void *private, |
695 | int (*populate)(struct dentry *, void *), void *args_populate) |
696 | { |
697 | struct dentry *dentry; |
698 | struct inode *dir = parent->d_inode; |
699 | int error; |
700 | |
701 | mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); |
702 | dentry = __rpc_lookup_create_exclusive(parent, name); |
703 | if (IS_ERR(dentry)) |
704 | goto out; |
705 | error = __rpc_mkdir(dir, dentry, mode, NULL, private); |
706 | if (error != 0) |
707 | goto out_err; |
708 | if (populate != NULL) { |
709 | error = populate(dentry, args_populate); |
710 | if (error) |
711 | goto err_rmdir; |
712 | } |
713 | out: |
714 | mutex_unlock(&dir->i_mutex); |
715 | return dentry; |
716 | err_rmdir: |
717 | __rpc_rmdir(dir, dentry); |
718 | out_err: |
719 | dentry = ERR_PTR(error); |
720 | goto out; |
721 | } |
722 | |
723 | static int rpc_rmdir_depopulate(struct dentry *dentry, |
724 | void (*depopulate)(struct dentry *)) |
725 | { |
726 | struct dentry *parent; |
727 | struct inode *dir; |
728 | int error; |
729 | |
730 | parent = dget_parent(dentry); |
731 | dir = parent->d_inode; |
732 | mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); |
733 | if (depopulate != NULL) |
734 | depopulate(dentry); |
735 | error = __rpc_rmdir(dir, dentry); |
736 | mutex_unlock(&dir->i_mutex); |
737 | dput(parent); |
738 | return error; |
739 | } |
740 | |
741 | /** |
742 | * rpc_mkpipe - make an rpc_pipefs file for kernel<->userspace communication |
743 | * @parent: dentry of directory to create new "pipe" in |
744 | * @name: name of pipe |
745 | * @private: private data to associate with the pipe, for the caller's use |
746 | * @ops: operations defining the behavior of the pipe: upcall, downcall, |
747 | * release_pipe, open_pipe, and destroy_msg. |
748 | * @flags: rpc_inode flags |
749 | * |
750 | * Data is made available for userspace to read by calls to |
751 | * rpc_queue_upcall(). The actual reads will result in calls to |
752 | * @ops->upcall, which will be called with the file pointer, |
753 | * message, and userspace buffer to copy to. |
754 | * |
755 | * Writes can come at any time, and do not necessarily have to be |
756 | * responses to upcalls. They will result in calls to @msg->downcall. |
757 | * |
758 | * The @private argument passed here will be available to all these methods |
759 | * from the file pointer, via RPC_I(file->f_dentry->d_inode)->private. |
760 | */ |
761 | struct dentry *rpc_mkpipe(struct dentry *parent, const char *name, |
762 | void *private, const struct rpc_pipe_ops *ops, |
763 | int flags) |
764 | { |
765 | struct dentry *dentry; |
766 | struct inode *dir = parent->d_inode; |
767 | umode_t umode = S_IFIFO | S_IRUSR | S_IWUSR; |
768 | struct qstr q; |
769 | int err; |
770 | |
771 | if (ops->upcall == NULL) |
772 | umode &= ~S_IRUGO; |
773 | if (ops->downcall == NULL) |
774 | umode &= ~S_IWUGO; |
775 | |
776 | q.name = name; |
777 | q.len = strlen(name); |
778 | q.hash = full_name_hash(q.name, q.len), |
779 | |
780 | mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); |
781 | dentry = __rpc_lookup_create(parent, &q); |
782 | if (IS_ERR(dentry)) |
783 | goto out; |
784 | if (dentry->d_inode) { |
785 | struct rpc_inode *rpci = RPC_I(dentry->d_inode); |
786 | if (rpci->private != private || |
787 | rpci->ops != ops || |
788 | rpci->flags != flags) { |
789 | dput (dentry); |
790 | err = -EBUSY; |
791 | goto out_err; |
792 | } |
793 | rpci->nkern_readwriters++; |
794 | goto out; |
795 | } |
796 | |
797 | err = __rpc_mkpipe(dir, dentry, umode, &rpc_pipe_fops, |
798 | private, ops, flags); |
799 | if (err) |
800 | goto out_err; |
801 | out: |
802 | mutex_unlock(&dir->i_mutex); |
803 | return dentry; |
804 | out_err: |
805 | dentry = ERR_PTR(err); |
806 | printk(KERN_WARNING "%s: %s() failed to create pipe %s/%s (errno = %d)\n", |
807 | __FILE__, __func__, parent->d_name.name, name, |
808 | err); |
809 | goto out; |
810 | } |
811 | EXPORT_SYMBOL_GPL(rpc_mkpipe); |
812 | |
813 | /** |
814 | * rpc_unlink - remove a pipe |
815 | * @dentry: dentry for the pipe, as returned from rpc_mkpipe |
816 | * |
817 | * After this call, lookups will no longer find the pipe, and any |
818 | * attempts to read or write using preexisting opens of the pipe will |
819 | * return -EPIPE. |
820 | */ |
821 | int |
822 | rpc_unlink(struct dentry *dentry) |
823 | { |
824 | struct dentry *parent; |
825 | struct inode *dir; |
826 | int error = 0; |
827 | |
828 | parent = dget_parent(dentry); |
829 | dir = parent->d_inode; |
830 | mutex_lock_nested(&dir->i_mutex, I_MUTEX_PARENT); |
831 | error = __rpc_rmpipe(dir, dentry); |
832 | mutex_unlock(&dir->i_mutex); |
833 | dput(parent); |
834 | return error; |
835 | } |
836 | EXPORT_SYMBOL_GPL(rpc_unlink); |
837 | |
838 | enum { |
839 | RPCAUTH_info, |
840 | RPCAUTH_EOF |
841 | }; |
842 | |
843 | static const struct rpc_filelist authfiles[] = { |
844 | [RPCAUTH_info] = { |
845 | .name = "info", |
846 | .i_fop = &rpc_info_operations, |
847 | .mode = S_IFREG | S_IRUSR, |
848 | }, |
849 | }; |
850 | |
851 | static int rpc_clntdir_populate(struct dentry *dentry, void *private) |
852 | { |
853 | return rpc_populate(dentry, |
854 | authfiles, RPCAUTH_info, RPCAUTH_EOF, |
855 | private); |
856 | } |
857 | |
858 | static void rpc_clntdir_depopulate(struct dentry *dentry) |
859 | { |
860 | rpc_depopulate(dentry, authfiles, RPCAUTH_info, RPCAUTH_EOF); |
861 | } |
862 | |
863 | /** |
864 | * rpc_create_client_dir - Create a new rpc_client directory in rpc_pipefs |
865 | * @dentry: dentry from the rpc_pipefs root to the new directory |
866 | * @name: &struct qstr for the name |
867 | * @rpc_client: rpc client to associate with this directory |
868 | * |
869 | * This creates a directory at the given @path associated with |
870 | * @rpc_clnt, which will contain a file named "info" with some basic |
871 | * information about the client, together with any "pipes" that may |
872 | * later be created using rpc_mkpipe(). |
873 | */ |
874 | struct dentry *rpc_create_client_dir(struct dentry *dentry, |
875 | struct qstr *name, |
876 | struct rpc_clnt *rpc_client) |
877 | { |
878 | return rpc_mkdir_populate(dentry, name, S_IRUGO | S_IXUGO, NULL, |
879 | rpc_clntdir_populate, rpc_client); |
880 | } |
881 | |
882 | /** |
883 | * rpc_remove_client_dir - Remove a directory created with rpc_create_client_dir() |
884 | * @dentry: directory to remove |
885 | */ |
886 | int rpc_remove_client_dir(struct dentry *dentry) |
887 | { |
888 | return rpc_rmdir_depopulate(dentry, rpc_clntdir_depopulate); |
889 | } |
890 | |
891 | static const struct rpc_filelist cache_pipefs_files[3] = { |
892 | [0] = { |
893 | .name = "channel", |
894 | .i_fop = &cache_file_operations_pipefs, |
895 | .mode = S_IFREG|S_IRUSR|S_IWUSR, |
896 | }, |
897 | [1] = { |
898 | .name = "content", |
899 | .i_fop = &content_file_operations_pipefs, |
900 | .mode = S_IFREG|S_IRUSR, |
901 | }, |
902 | [2] = { |
903 | .name = "flush", |
904 | .i_fop = &cache_flush_operations_pipefs, |
905 | .mode = S_IFREG|S_IRUSR|S_IWUSR, |
906 | }, |
907 | }; |
908 | |
909 | static int rpc_cachedir_populate(struct dentry *dentry, void *private) |
910 | { |
911 | return rpc_populate(dentry, |
912 | cache_pipefs_files, 0, 3, |
913 | private); |
914 | } |
915 | |
916 | static void rpc_cachedir_depopulate(struct dentry *dentry) |
917 | { |
918 | rpc_depopulate(dentry, cache_pipefs_files, 0, 3); |
919 | } |
920 | |
921 | struct dentry *rpc_create_cache_dir(struct dentry *parent, struct qstr *name, |
922 | mode_t umode, struct cache_detail *cd) |
923 | { |
924 | return rpc_mkdir_populate(parent, name, umode, NULL, |
925 | rpc_cachedir_populate, cd); |
926 | } |
927 | |
928 | void rpc_remove_cache_dir(struct dentry *dentry) |
929 | { |
930 | rpc_rmdir_depopulate(dentry, rpc_cachedir_depopulate); |
931 | } |
932 | |
933 | /* |
934 | * populate the filesystem |
935 | */ |
936 | static const struct super_operations s_ops = { |
937 | .alloc_inode = rpc_alloc_inode, |
938 | .destroy_inode = rpc_destroy_inode, |
939 | .statfs = simple_statfs, |
940 | }; |
941 | |
942 | #define RPCAUTH_GSSMAGIC 0x67596969 |
943 | |
944 | /* |
945 | * We have a single directory with 1 node in it. |
946 | */ |
947 | enum { |
948 | RPCAUTH_lockd, |
949 | RPCAUTH_mount, |
950 | RPCAUTH_nfs, |
951 | RPCAUTH_portmap, |
952 | RPCAUTH_statd, |
953 | RPCAUTH_nfsd4_cb, |
954 | RPCAUTH_cache, |
955 | RPCAUTH_RootEOF |
956 | }; |
957 | |
958 | static const struct rpc_filelist files[] = { |
959 | [RPCAUTH_lockd] = { |
960 | .name = "lockd", |
961 | .mode = S_IFDIR | S_IRUGO | S_IXUGO, |
962 | }, |
963 | [RPCAUTH_mount] = { |
964 | .name = "mount", |
965 | .mode = S_IFDIR | S_IRUGO | S_IXUGO, |
966 | }, |
967 | [RPCAUTH_nfs] = { |
968 | .name = "nfs", |
969 | .mode = S_IFDIR | S_IRUGO | S_IXUGO, |
970 | }, |
971 | [RPCAUTH_portmap] = { |
972 | .name = "portmap", |
973 | .mode = S_IFDIR | S_IRUGO | S_IXUGO, |
974 | }, |
975 | [RPCAUTH_statd] = { |
976 | .name = "statd", |
977 | .mode = S_IFDIR | S_IRUGO | S_IXUGO, |
978 | }, |
979 | [RPCAUTH_nfsd4_cb] = { |
980 | .name = "nfsd4_cb", |
981 | .mode = S_IFDIR | S_IRUGO | S_IXUGO, |
982 | }, |
983 | [RPCAUTH_cache] = { |
984 | .name = "cache", |
985 | .mode = S_IFDIR | S_IRUGO | S_IXUGO, |
986 | }, |
987 | }; |
988 | |
989 | static int |
990 | rpc_fill_super(struct super_block *sb, void *data, int silent) |
991 | { |
992 | struct inode *inode; |
993 | struct dentry *root; |
994 | |
995 | sb->s_blocksize = PAGE_CACHE_SIZE; |
996 | sb->s_blocksize_bits = PAGE_CACHE_SHIFT; |
997 | sb->s_magic = RPCAUTH_GSSMAGIC; |
998 | sb->s_op = &s_ops; |
999 | sb->s_time_gran = 1; |
1000 | |
1001 | inode = rpc_get_inode(sb, S_IFDIR | 0755); |
1002 | if (!inode) |
1003 | return -ENOMEM; |
1004 | sb->s_root = root = d_alloc_root(inode); |
1005 | if (!root) { |
1006 | iput(inode); |
1007 | return -ENOMEM; |
1008 | } |
1009 | if (rpc_populate(root, files, RPCAUTH_lockd, RPCAUTH_RootEOF, NULL)) |
1010 | return -ENOMEM; |
1011 | return 0; |
1012 | } |
1013 | |
1014 | static int |
1015 | rpc_get_sb(struct file_system_type *fs_type, |
1016 | int flags, const char *dev_name, void *data, struct vfsmount *mnt) |
1017 | { |
1018 | return get_sb_single(fs_type, flags, data, rpc_fill_super, mnt); |
1019 | } |
1020 | |
1021 | static struct file_system_type rpc_pipe_fs_type = { |
1022 | .owner = THIS_MODULE, |
1023 | .name = "rpc_pipefs", |
1024 | .get_sb = rpc_get_sb, |
1025 | .kill_sb = kill_litter_super, |
1026 | }; |
1027 | |
1028 | static void |
1029 | init_once(void *foo) |
1030 | { |
1031 | struct rpc_inode *rpci = (struct rpc_inode *) foo; |
1032 | |
1033 | inode_init_once(&rpci->vfs_inode); |
1034 | rpci->private = NULL; |
1035 | rpci->nreaders = 0; |
1036 | rpci->nwriters = 0; |
1037 | INIT_LIST_HEAD(&rpci->in_upcall); |
1038 | INIT_LIST_HEAD(&rpci->in_downcall); |
1039 | INIT_LIST_HEAD(&rpci->pipe); |
1040 | rpci->pipelen = 0; |
1041 | init_waitqueue_head(&rpci->waitq); |
1042 | INIT_DELAYED_WORK(&rpci->queue_timeout, |
1043 | rpc_timeout_upcall_queue); |
1044 | rpci->ops = NULL; |
1045 | } |
1046 | |
1047 | int register_rpc_pipefs(void) |
1048 | { |
1049 | int err; |
1050 | |
1051 | rpc_inode_cachep = kmem_cache_create("rpc_inode_cache", |
1052 | sizeof(struct rpc_inode), |
1053 | 0, (SLAB_HWCACHE_ALIGN|SLAB_RECLAIM_ACCOUNT| |
1054 | SLAB_MEM_SPREAD), |
1055 | init_once); |
1056 | if (!rpc_inode_cachep) |
1057 | return -ENOMEM; |
1058 | err = register_filesystem(&rpc_pipe_fs_type); |
1059 | if (err) { |
1060 | kmem_cache_destroy(rpc_inode_cachep); |
1061 | return err; |
1062 | } |
1063 | |
1064 | return 0; |
1065 | } |
1066 | |
1067 | void unregister_rpc_pipefs(void) |
1068 | { |
1069 | kmem_cache_destroy(rpc_inode_cachep); |
1070 | unregister_filesystem(&rpc_pipe_fs_type); |
1071 | } |
1072 |
Branches:
ben-wpan
ben-wpan-stefan
javiroman/ks7010
jz-2.6.34
jz-2.6.34-rc5
jz-2.6.34-rc6
jz-2.6.34-rc7
jz-2.6.35
jz-2.6.36
jz-2.6.37
jz-2.6.38
jz-2.6.39
jz-3.0
jz-3.1
jz-3.11
jz-3.12
jz-3.13
jz-3.15
jz-3.16
jz-3.18-dt
jz-3.2
jz-3.3
jz-3.4
jz-3.5
jz-3.6
jz-3.6-rc2-pwm
jz-3.9
jz-3.9-clk
jz-3.9-rc8
jz47xx
jz47xx-2.6.38
master
Tags:
od-2011-09-04
od-2011-09-18
v2.6.34-rc5
v2.6.34-rc6
v2.6.34-rc7
v3.9