Contents of /alx-src/tags/kernel26-2.6.12-alx-r9/ipc/mqueue.c
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Wed Mar 4 11:03:09 2009 UTC (15 years, 3 months ago) by niro
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File size: 29809 byte(s)
Wed Mar 4 11:03:09 2009 UTC (15 years, 3 months ago) by niro
File MIME type: text/plain
File size: 29809 byte(s)
Tag kernel26-2.6.12-alx-r9
1 | /* |
2 | * POSIX message queues filesystem for Linux. |
3 | * |
4 | * Copyright (C) 2003,2004 Krzysztof Benedyczak (golbi@mat.uni.torun.pl) |
5 | * Michal Wronski (wrona@mat.uni.torun.pl) |
6 | * |
7 | * Spinlocks: Mohamed Abbas (abbas.mohamed@intel.com) |
8 | * Lockless receive & send, fd based notify: |
9 | * Manfred Spraul (manfred@colorfullife.com) |
10 | * |
11 | * This file is released under the GPL. |
12 | */ |
13 | |
14 | #include <linux/init.h> |
15 | #include <linux/pagemap.h> |
16 | #include <linux/file.h> |
17 | #include <linux/mount.h> |
18 | #include <linux/namei.h> |
19 | #include <linux/sysctl.h> |
20 | #include <linux/poll.h> |
21 | #include <linux/mqueue.h> |
22 | #include <linux/msg.h> |
23 | #include <linux/skbuff.h> |
24 | #include <linux/netlink.h> |
25 | #include <linux/syscalls.h> |
26 | #include <linux/signal.h> |
27 | #include <net/sock.h> |
28 | #include "util.h" |
29 | |
30 | #define MQUEUE_MAGIC 0x19800202 |
31 | #define DIRENT_SIZE 20 |
32 | #define FILENT_SIZE 80 |
33 | |
34 | #define SEND 0 |
35 | #define RECV 1 |
36 | |
37 | #define STATE_NONE 0 |
38 | #define STATE_PENDING 1 |
39 | #define STATE_READY 2 |
40 | |
41 | /* used by sysctl */ |
42 | #define FS_MQUEUE 1 |
43 | #define CTL_QUEUESMAX 2 |
44 | #define CTL_MSGMAX 3 |
45 | #define CTL_MSGSIZEMAX 4 |
46 | |
47 | /* default values */ |
48 | #define DFLT_QUEUESMAX 256 /* max number of message queues */ |
49 | #define DFLT_MSGMAX 10 /* max number of messages in each queue */ |
50 | #define HARD_MSGMAX (131072/sizeof(void*)) |
51 | #define DFLT_MSGSIZEMAX 8192 /* max message size */ |
52 | |
53 | #define NOTIFY_COOKIE_LEN 32 |
54 | |
55 | struct ext_wait_queue { /* queue of sleeping tasks */ |
56 | struct task_struct *task; |
57 | struct list_head list; |
58 | struct msg_msg *msg; /* ptr of loaded message */ |
59 | int state; /* one of STATE_* values */ |
60 | }; |
61 | |
62 | struct mqueue_inode_info { |
63 | spinlock_t lock; |
64 | struct inode vfs_inode; |
65 | wait_queue_head_t wait_q; |
66 | |
67 | struct msg_msg **messages; |
68 | struct mq_attr attr; |
69 | |
70 | struct sigevent notify; |
71 | pid_t notify_owner; |
72 | struct user_struct *user; /* user who created, for accouting */ |
73 | struct sock *notify_sock; |
74 | struct sk_buff *notify_cookie; |
75 | |
76 | /* for tasks waiting for free space and messages, respectively */ |
77 | struct ext_wait_queue e_wait_q[2]; |
78 | |
79 | unsigned long qsize; /* size of queue in memory (sum of all msgs) */ |
80 | }; |
81 | |
82 | static struct inode_operations mqueue_dir_inode_operations; |
83 | static struct file_operations mqueue_file_operations; |
84 | static struct super_operations mqueue_super_ops; |
85 | static void remove_notification(struct mqueue_inode_info *info); |
86 | |
87 | static spinlock_t mq_lock; |
88 | static kmem_cache_t *mqueue_inode_cachep; |
89 | static struct vfsmount *mqueue_mnt; |
90 | |
91 | static unsigned int queues_count; |
92 | static unsigned int queues_max = DFLT_QUEUESMAX; |
93 | static unsigned int msg_max = DFLT_MSGMAX; |
94 | static unsigned int msgsize_max = DFLT_MSGSIZEMAX; |
95 | |
96 | static struct ctl_table_header * mq_sysctl_table; |
97 | |
98 | static inline struct mqueue_inode_info *MQUEUE_I(struct inode *inode) |
99 | { |
100 | return container_of(inode, struct mqueue_inode_info, vfs_inode); |
101 | } |
102 | |
103 | static struct inode *mqueue_get_inode(struct super_block *sb, int mode, |
104 | struct mq_attr *attr) |
105 | { |
106 | struct inode *inode; |
107 | |
108 | inode = new_inode(sb); |
109 | if (inode) { |
110 | inode->i_mode = mode; |
111 | inode->i_uid = current->fsuid; |
112 | inode->i_gid = current->fsgid; |
113 | inode->i_blksize = PAGE_CACHE_SIZE; |
114 | inode->i_blocks = 0; |
115 | inode->i_mtime = inode->i_ctime = inode->i_atime = |
116 | CURRENT_TIME; |
117 | |
118 | if (S_ISREG(mode)) { |
119 | struct mqueue_inode_info *info; |
120 | struct task_struct *p = current; |
121 | struct user_struct *u = p->user; |
122 | unsigned long mq_bytes, mq_msg_tblsz; |
123 | |
124 | inode->i_fop = &mqueue_file_operations; |
125 | inode->i_size = FILENT_SIZE; |
126 | /* mqueue specific info */ |
127 | info = MQUEUE_I(inode); |
128 | spin_lock_init(&info->lock); |
129 | init_waitqueue_head(&info->wait_q); |
130 | INIT_LIST_HEAD(&info->e_wait_q[0].list); |
131 | INIT_LIST_HEAD(&info->e_wait_q[1].list); |
132 | info->messages = NULL; |
133 | info->notify_owner = 0; |
134 | info->qsize = 0; |
135 | info->user = NULL; /* set when all is ok */ |
136 | memset(&info->attr, 0, sizeof(info->attr)); |
137 | info->attr.mq_maxmsg = DFLT_MSGMAX; |
138 | info->attr.mq_msgsize = DFLT_MSGSIZEMAX; |
139 | if (attr) { |
140 | info->attr.mq_maxmsg = attr->mq_maxmsg; |
141 | info->attr.mq_msgsize = attr->mq_msgsize; |
142 | } |
143 | mq_msg_tblsz = info->attr.mq_maxmsg * sizeof(struct msg_msg *); |
144 | mq_bytes = (mq_msg_tblsz + |
145 | (info->attr.mq_maxmsg * info->attr.mq_msgsize)); |
146 | |
147 | spin_lock(&mq_lock); |
148 | if (u->mq_bytes + mq_bytes < u->mq_bytes || |
149 | u->mq_bytes + mq_bytes > |
150 | p->signal->rlim[RLIMIT_MSGQUEUE].rlim_cur) { |
151 | spin_unlock(&mq_lock); |
152 | goto out_inode; |
153 | } |
154 | u->mq_bytes += mq_bytes; |
155 | spin_unlock(&mq_lock); |
156 | |
157 | info->messages = kmalloc(mq_msg_tblsz, GFP_KERNEL); |
158 | if (!info->messages) { |
159 | spin_lock(&mq_lock); |
160 | u->mq_bytes -= mq_bytes; |
161 | spin_unlock(&mq_lock); |
162 | goto out_inode; |
163 | } |
164 | /* all is ok */ |
165 | info->user = get_uid(u); |
166 | } else if (S_ISDIR(mode)) { |
167 | inode->i_nlink++; |
168 | /* Some things misbehave if size == 0 on a directory */ |
169 | inode->i_size = 2 * DIRENT_SIZE; |
170 | inode->i_op = &mqueue_dir_inode_operations; |
171 | inode->i_fop = &simple_dir_operations; |
172 | } |
173 | } |
174 | return inode; |
175 | out_inode: |
176 | make_bad_inode(inode); |
177 | iput(inode); |
178 | return NULL; |
179 | } |
180 | |
181 | static int mqueue_fill_super(struct super_block *sb, void *data, int silent) |
182 | { |
183 | struct inode *inode; |
184 | |
185 | sb->s_blocksize = PAGE_CACHE_SIZE; |
186 | sb->s_blocksize_bits = PAGE_CACHE_SHIFT; |
187 | sb->s_magic = MQUEUE_MAGIC; |
188 | sb->s_op = &mqueue_super_ops; |
189 | |
190 | inode = mqueue_get_inode(sb, S_IFDIR | S_ISVTX | S_IRWXUGO, NULL); |
191 | if (!inode) |
192 | return -ENOMEM; |
193 | |
194 | sb->s_root = d_alloc_root(inode); |
195 | if (!sb->s_root) { |
196 | iput(inode); |
197 | return -ENOMEM; |
198 | } |
199 | |
200 | return 0; |
201 | } |
202 | |
203 | static struct super_block *mqueue_get_sb(struct file_system_type *fs_type, |
204 | int flags, const char *dev_name, |
205 | void *data) |
206 | { |
207 | return get_sb_single(fs_type, flags, data, mqueue_fill_super); |
208 | } |
209 | |
210 | static void init_once(void *foo, kmem_cache_t * cachep, unsigned long flags) |
211 | { |
212 | struct mqueue_inode_info *p = (struct mqueue_inode_info *) foo; |
213 | |
214 | if ((flags & (SLAB_CTOR_VERIFY | SLAB_CTOR_CONSTRUCTOR)) == |
215 | SLAB_CTOR_CONSTRUCTOR) |
216 | inode_init_once(&p->vfs_inode); |
217 | } |
218 | |
219 | static struct inode *mqueue_alloc_inode(struct super_block *sb) |
220 | { |
221 | struct mqueue_inode_info *ei; |
222 | |
223 | ei = kmem_cache_alloc(mqueue_inode_cachep, SLAB_KERNEL); |
224 | if (!ei) |
225 | return NULL; |
226 | return &ei->vfs_inode; |
227 | } |
228 | |
229 | static void mqueue_destroy_inode(struct inode *inode) |
230 | { |
231 | kmem_cache_free(mqueue_inode_cachep, MQUEUE_I(inode)); |
232 | } |
233 | |
234 | static void mqueue_delete_inode(struct inode *inode) |
235 | { |
236 | struct mqueue_inode_info *info; |
237 | struct user_struct *user; |
238 | unsigned long mq_bytes; |
239 | int i; |
240 | |
241 | if (S_ISDIR(inode->i_mode)) { |
242 | clear_inode(inode); |
243 | return; |
244 | } |
245 | info = MQUEUE_I(inode); |
246 | spin_lock(&info->lock); |
247 | for (i = 0; i < info->attr.mq_curmsgs; i++) |
248 | free_msg(info->messages[i]); |
249 | kfree(info->messages); |
250 | spin_unlock(&info->lock); |
251 | |
252 | clear_inode(inode); |
253 | |
254 | mq_bytes = (info->attr.mq_maxmsg * sizeof(struct msg_msg *) + |
255 | (info->attr.mq_maxmsg * info->attr.mq_msgsize)); |
256 | user = info->user; |
257 | if (user) { |
258 | spin_lock(&mq_lock); |
259 | user->mq_bytes -= mq_bytes; |
260 | queues_count--; |
261 | spin_unlock(&mq_lock); |
262 | free_uid(user); |
263 | } |
264 | } |
265 | |
266 | static int mqueue_create(struct inode *dir, struct dentry *dentry, |
267 | int mode, struct nameidata *nd) |
268 | { |
269 | struct inode *inode; |
270 | struct mq_attr *attr = dentry->d_fsdata; |
271 | int error; |
272 | |
273 | spin_lock(&mq_lock); |
274 | if (queues_count >= queues_max && !capable(CAP_SYS_RESOURCE)) { |
275 | error = -ENOSPC; |
276 | goto out_lock; |
277 | } |
278 | queues_count++; |
279 | spin_unlock(&mq_lock); |
280 | |
281 | inode = mqueue_get_inode(dir->i_sb, mode, attr); |
282 | if (!inode) { |
283 | error = -ENOMEM; |
284 | spin_lock(&mq_lock); |
285 | queues_count--; |
286 | goto out_lock; |
287 | } |
288 | |
289 | dir->i_size += DIRENT_SIZE; |
290 | dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME; |
291 | |
292 | d_instantiate(dentry, inode); |
293 | dget(dentry); |
294 | return 0; |
295 | out_lock: |
296 | spin_unlock(&mq_lock); |
297 | return error; |
298 | } |
299 | |
300 | static int mqueue_unlink(struct inode *dir, struct dentry *dentry) |
301 | { |
302 | struct inode *inode = dentry->d_inode; |
303 | |
304 | dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME; |
305 | dir->i_size -= DIRENT_SIZE; |
306 | inode->i_nlink--; |
307 | dput(dentry); |
308 | return 0; |
309 | } |
310 | |
311 | /* |
312 | * This is routine for system read from queue file. |
313 | * To avoid mess with doing here some sort of mq_receive we allow |
314 | * to read only queue size & notification info (the only values |
315 | * that are interesting from user point of view and aren't accessible |
316 | * through std routines) |
317 | */ |
318 | static ssize_t mqueue_read_file(struct file *filp, char __user *u_data, |
319 | size_t count, loff_t * off) |
320 | { |
321 | struct mqueue_inode_info *info = MQUEUE_I(filp->f_dentry->d_inode); |
322 | char buffer[FILENT_SIZE]; |
323 | size_t slen; |
324 | loff_t o; |
325 | |
326 | if (!count) |
327 | return 0; |
328 | |
329 | spin_lock(&info->lock); |
330 | snprintf(buffer, sizeof(buffer), |
331 | "QSIZE:%-10lu NOTIFY:%-5d SIGNO:%-5d NOTIFY_PID:%-6d\n", |
332 | info->qsize, |
333 | info->notify_owner ? info->notify.sigev_notify : 0, |
334 | (info->notify_owner && |
335 | info->notify.sigev_notify == SIGEV_SIGNAL) ? |
336 | info->notify.sigev_signo : 0, |
337 | info->notify_owner); |
338 | spin_unlock(&info->lock); |
339 | buffer[sizeof(buffer)-1] = '\0'; |
340 | slen = strlen(buffer)+1; |
341 | |
342 | o = *off; |
343 | if (o > slen) |
344 | return 0; |
345 | |
346 | if (o + count > slen) |
347 | count = slen - o; |
348 | |
349 | if (copy_to_user(u_data, buffer + o, count)) |
350 | return -EFAULT; |
351 | |
352 | *off = o + count; |
353 | filp->f_dentry->d_inode->i_atime = filp->f_dentry->d_inode->i_ctime = CURRENT_TIME; |
354 | return count; |
355 | } |
356 | |
357 | static int mqueue_flush_file(struct file *filp) |
358 | { |
359 | struct mqueue_inode_info *info = MQUEUE_I(filp->f_dentry->d_inode); |
360 | |
361 | spin_lock(&info->lock); |
362 | if (current->tgid == info->notify_owner) |
363 | remove_notification(info); |
364 | |
365 | spin_unlock(&info->lock); |
366 | return 0; |
367 | } |
368 | |
369 | static unsigned int mqueue_poll_file(struct file *filp, struct poll_table_struct *poll_tab) |
370 | { |
371 | struct mqueue_inode_info *info = MQUEUE_I(filp->f_dentry->d_inode); |
372 | int retval = 0; |
373 | |
374 | poll_wait(filp, &info->wait_q, poll_tab); |
375 | |
376 | spin_lock(&info->lock); |
377 | if (info->attr.mq_curmsgs) |
378 | retval = POLLIN | POLLRDNORM; |
379 | |
380 | if (info->attr.mq_curmsgs < info->attr.mq_maxmsg) |
381 | retval |= POLLOUT | POLLWRNORM; |
382 | spin_unlock(&info->lock); |
383 | |
384 | return retval; |
385 | } |
386 | |
387 | /* Adds current to info->e_wait_q[sr] before element with smaller prio */ |
388 | static void wq_add(struct mqueue_inode_info *info, int sr, |
389 | struct ext_wait_queue *ewp) |
390 | { |
391 | struct ext_wait_queue *walk; |
392 | |
393 | ewp->task = current; |
394 | |
395 | list_for_each_entry(walk, &info->e_wait_q[sr].list, list) { |
396 | if (walk->task->static_prio <= current->static_prio) { |
397 | list_add_tail(&ewp->list, &walk->list); |
398 | return; |
399 | } |
400 | } |
401 | list_add_tail(&ewp->list, &info->e_wait_q[sr].list); |
402 | } |
403 | |
404 | /* |
405 | * Puts current task to sleep. Caller must hold queue lock. After return |
406 | * lock isn't held. |
407 | * sr: SEND or RECV |
408 | */ |
409 | static int wq_sleep(struct mqueue_inode_info *info, int sr, |
410 | long timeout, struct ext_wait_queue *ewp) |
411 | { |
412 | int retval; |
413 | signed long time; |
414 | |
415 | wq_add(info, sr, ewp); |
416 | |
417 | for (;;) { |
418 | set_current_state(TASK_INTERRUPTIBLE); |
419 | |
420 | spin_unlock(&info->lock); |
421 | time = schedule_timeout(timeout); |
422 | |
423 | while (ewp->state == STATE_PENDING) |
424 | cpu_relax(); |
425 | |
426 | if (ewp->state == STATE_READY) { |
427 | retval = 0; |
428 | goto out; |
429 | } |
430 | spin_lock(&info->lock); |
431 | if (ewp->state == STATE_READY) { |
432 | retval = 0; |
433 | goto out_unlock; |
434 | } |
435 | if (signal_pending(current)) { |
436 | retval = -ERESTARTSYS; |
437 | break; |
438 | } |
439 | if (time == 0) { |
440 | retval = -ETIMEDOUT; |
441 | break; |
442 | } |
443 | } |
444 | list_del(&ewp->list); |
445 | out_unlock: |
446 | spin_unlock(&info->lock); |
447 | out: |
448 | return retval; |
449 | } |
450 | |
451 | /* |
452 | * Returns waiting task that should be serviced first or NULL if none exists |
453 | */ |
454 | static struct ext_wait_queue *wq_get_first_waiter( |
455 | struct mqueue_inode_info *info, int sr) |
456 | { |
457 | struct list_head *ptr; |
458 | |
459 | ptr = info->e_wait_q[sr].list.prev; |
460 | if (ptr == &info->e_wait_q[sr].list) |
461 | return NULL; |
462 | return list_entry(ptr, struct ext_wait_queue, list); |
463 | } |
464 | |
465 | /* Auxiliary functions to manipulate messages' list */ |
466 | static void msg_insert(struct msg_msg *ptr, struct mqueue_inode_info *info) |
467 | { |
468 | int k; |
469 | |
470 | k = info->attr.mq_curmsgs - 1; |
471 | while (k >= 0 && info->messages[k]->m_type >= ptr->m_type) { |
472 | info->messages[k + 1] = info->messages[k]; |
473 | k--; |
474 | } |
475 | info->attr.mq_curmsgs++; |
476 | info->qsize += ptr->m_ts; |
477 | info->messages[k + 1] = ptr; |
478 | } |
479 | |
480 | static inline struct msg_msg *msg_get(struct mqueue_inode_info *info) |
481 | { |
482 | info->qsize -= info->messages[--info->attr.mq_curmsgs]->m_ts; |
483 | return info->messages[info->attr.mq_curmsgs]; |
484 | } |
485 | |
486 | static inline void set_cookie(struct sk_buff *skb, char code) |
487 | { |
488 | ((char*)skb->data)[NOTIFY_COOKIE_LEN-1] = code; |
489 | } |
490 | |
491 | /* |
492 | * The next function is only to split too long sys_mq_timedsend |
493 | */ |
494 | static void __do_notify(struct mqueue_inode_info *info) |
495 | { |
496 | /* notification |
497 | * invoked when there is registered process and there isn't process |
498 | * waiting synchronously for message AND state of queue changed from |
499 | * empty to not empty. Here we are sure that no one is waiting |
500 | * synchronously. */ |
501 | if (info->notify_owner && |
502 | info->attr.mq_curmsgs == 1) { |
503 | struct siginfo sig_i; |
504 | switch (info->notify.sigev_notify) { |
505 | case SIGEV_NONE: |
506 | break; |
507 | case SIGEV_SIGNAL: |
508 | /* sends signal */ |
509 | |
510 | sig_i.si_signo = info->notify.sigev_signo; |
511 | sig_i.si_errno = 0; |
512 | sig_i.si_code = SI_MESGQ; |
513 | sig_i.si_value = info->notify.sigev_value; |
514 | sig_i.si_pid = current->tgid; |
515 | sig_i.si_uid = current->uid; |
516 | |
517 | kill_proc_info(info->notify.sigev_signo, |
518 | &sig_i, info->notify_owner); |
519 | break; |
520 | case SIGEV_THREAD: |
521 | set_cookie(info->notify_cookie, NOTIFY_WOKENUP); |
522 | netlink_sendskb(info->notify_sock, |
523 | info->notify_cookie, 0); |
524 | break; |
525 | } |
526 | /* after notification unregisters process */ |
527 | info->notify_owner = 0; |
528 | } |
529 | wake_up(&info->wait_q); |
530 | } |
531 | |
532 | static long prepare_timeout(const struct timespec __user *u_arg) |
533 | { |
534 | struct timespec ts, nowts; |
535 | long timeout; |
536 | |
537 | if (u_arg) { |
538 | if (unlikely(copy_from_user(&ts, u_arg, |
539 | sizeof(struct timespec)))) |
540 | return -EFAULT; |
541 | |
542 | if (unlikely(ts.tv_nsec < 0 || ts.tv_sec < 0 |
543 | || ts.tv_nsec >= NSEC_PER_SEC)) |
544 | return -EINVAL; |
545 | nowts = CURRENT_TIME; |
546 | /* first subtract as jiffies can't be too big */ |
547 | ts.tv_sec -= nowts.tv_sec; |
548 | if (ts.tv_nsec < nowts.tv_nsec) { |
549 | ts.tv_nsec += NSEC_PER_SEC; |
550 | ts.tv_sec--; |
551 | } |
552 | ts.tv_nsec -= nowts.tv_nsec; |
553 | if (ts.tv_sec < 0) |
554 | return 0; |
555 | |
556 | timeout = timespec_to_jiffies(&ts) + 1; |
557 | } else |
558 | return MAX_SCHEDULE_TIMEOUT; |
559 | |
560 | return timeout; |
561 | } |
562 | |
563 | static void remove_notification(struct mqueue_inode_info *info) |
564 | { |
565 | if (info->notify_owner != 0 && |
566 | info->notify.sigev_notify == SIGEV_THREAD) { |
567 | set_cookie(info->notify_cookie, NOTIFY_REMOVED); |
568 | netlink_sendskb(info->notify_sock, info->notify_cookie, 0); |
569 | } |
570 | info->notify_owner = 0; |
571 | } |
572 | |
573 | static int mq_attr_ok(struct mq_attr *attr) |
574 | { |
575 | if (attr->mq_maxmsg <= 0 || attr->mq_msgsize <= 0) |
576 | return 0; |
577 | if (capable(CAP_SYS_RESOURCE)) { |
578 | if (attr->mq_maxmsg > HARD_MSGMAX) |
579 | return 0; |
580 | } else { |
581 | if (attr->mq_maxmsg > msg_max || |
582 | attr->mq_msgsize > msgsize_max) |
583 | return 0; |
584 | } |
585 | /* check for overflow */ |
586 | if (attr->mq_msgsize > ULONG_MAX/attr->mq_maxmsg) |
587 | return 0; |
588 | if ((unsigned long)(attr->mq_maxmsg * attr->mq_msgsize) + |
589 | (attr->mq_maxmsg * sizeof (struct msg_msg *)) < |
590 | (unsigned long)(attr->mq_maxmsg * attr->mq_msgsize)) |
591 | return 0; |
592 | return 1; |
593 | } |
594 | |
595 | /* |
596 | * Invoked when creating a new queue via sys_mq_open |
597 | */ |
598 | static struct file *do_create(struct dentry *dir, struct dentry *dentry, |
599 | int oflag, mode_t mode, struct mq_attr __user *u_attr) |
600 | { |
601 | struct file *filp; |
602 | struct mq_attr attr; |
603 | int ret; |
604 | |
605 | if (u_attr != NULL) { |
606 | if (copy_from_user(&attr, u_attr, sizeof(attr))) |
607 | return ERR_PTR(-EFAULT); |
608 | if (!mq_attr_ok(&attr)) |
609 | return ERR_PTR(-EINVAL); |
610 | /* store for use during create */ |
611 | dentry->d_fsdata = &attr; |
612 | } |
613 | |
614 | ret = vfs_create(dir->d_inode, dentry, mode, NULL); |
615 | dentry->d_fsdata = NULL; |
616 | if (ret) |
617 | return ERR_PTR(ret); |
618 | |
619 | filp = dentry_open(dentry, mqueue_mnt, oflag); |
620 | if (!IS_ERR(filp)) |
621 | dget(dentry); |
622 | |
623 | return filp; |
624 | } |
625 | |
626 | /* Opens existing queue */ |
627 | static struct file *do_open(struct dentry *dentry, int oflag) |
628 | { |
629 | static int oflag2acc[O_ACCMODE] = { MAY_READ, MAY_WRITE, |
630 | MAY_READ | MAY_WRITE }; |
631 | struct file *filp; |
632 | |
633 | if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY)) |
634 | return ERR_PTR(-EINVAL); |
635 | |
636 | if (permission(dentry->d_inode, oflag2acc[oflag & O_ACCMODE], NULL)) |
637 | return ERR_PTR(-EACCES); |
638 | |
639 | filp = dentry_open(dentry, mqueue_mnt, oflag); |
640 | |
641 | if (!IS_ERR(filp)) |
642 | dget(dentry); |
643 | |
644 | return filp; |
645 | } |
646 | |
647 | asmlinkage long sys_mq_open(const char __user *u_name, int oflag, mode_t mode, |
648 | struct mq_attr __user *u_attr) |
649 | { |
650 | struct dentry *dentry; |
651 | struct file *filp; |
652 | char *name; |
653 | int fd, error; |
654 | |
655 | if (IS_ERR(name = getname(u_name))) |
656 | return PTR_ERR(name); |
657 | |
658 | fd = get_unused_fd(); |
659 | if (fd < 0) |
660 | goto out_putname; |
661 | |
662 | down(&mqueue_mnt->mnt_root->d_inode->i_sem); |
663 | dentry = lookup_one_len(name, mqueue_mnt->mnt_root, strlen(name)); |
664 | if (IS_ERR(dentry)) { |
665 | error = PTR_ERR(dentry); |
666 | goto out_err; |
667 | } |
668 | mntget(mqueue_mnt); |
669 | |
670 | if (oflag & O_CREAT) { |
671 | if (dentry->d_inode) { /* entry already exists */ |
672 | filp = (oflag & O_EXCL) ? ERR_PTR(-EEXIST) : |
673 | do_open(dentry, oflag); |
674 | } else { |
675 | filp = do_create(mqueue_mnt->mnt_root, dentry, |
676 | oflag, mode, u_attr); |
677 | } |
678 | } else |
679 | filp = (dentry->d_inode) ? do_open(dentry, oflag) : |
680 | ERR_PTR(-ENOENT); |
681 | |
682 | dput(dentry); |
683 | |
684 | if (IS_ERR(filp)) { |
685 | error = PTR_ERR(filp); |
686 | goto out_putfd; |
687 | } |
688 | |
689 | set_close_on_exec(fd, 1); |
690 | fd_install(fd, filp); |
691 | goto out_upsem; |
692 | |
693 | out_putfd: |
694 | mntput(mqueue_mnt); |
695 | put_unused_fd(fd); |
696 | out_err: |
697 | fd = error; |
698 | out_upsem: |
699 | up(&mqueue_mnt->mnt_root->d_inode->i_sem); |
700 | out_putname: |
701 | putname(name); |
702 | return fd; |
703 | } |
704 | |
705 | asmlinkage long sys_mq_unlink(const char __user *u_name) |
706 | { |
707 | int err; |
708 | char *name; |
709 | struct dentry *dentry; |
710 | struct inode *inode = NULL; |
711 | |
712 | name = getname(u_name); |
713 | if (IS_ERR(name)) |
714 | return PTR_ERR(name); |
715 | |
716 | down(&mqueue_mnt->mnt_root->d_inode->i_sem); |
717 | dentry = lookup_one_len(name, mqueue_mnt->mnt_root, strlen(name)); |
718 | if (IS_ERR(dentry)) { |
719 | err = PTR_ERR(dentry); |
720 | goto out_unlock; |
721 | } |
722 | |
723 | if (!dentry->d_inode) { |
724 | err = -ENOENT; |
725 | goto out_err; |
726 | } |
727 | |
728 | inode = dentry->d_inode; |
729 | if (inode) |
730 | atomic_inc(&inode->i_count); |
731 | |
732 | err = vfs_unlink(dentry->d_parent->d_inode, dentry); |
733 | out_err: |
734 | dput(dentry); |
735 | |
736 | out_unlock: |
737 | up(&mqueue_mnt->mnt_root->d_inode->i_sem); |
738 | putname(name); |
739 | if (inode) |
740 | iput(inode); |
741 | |
742 | return err; |
743 | } |
744 | |
745 | /* Pipelined send and receive functions. |
746 | * |
747 | * If a receiver finds no waiting message, then it registers itself in the |
748 | * list of waiting receivers. A sender checks that list before adding the new |
749 | * message into the message array. If there is a waiting receiver, then it |
750 | * bypasses the message array and directly hands the message over to the |
751 | * receiver. |
752 | * The receiver accepts the message and returns without grabbing the queue |
753 | * spinlock. Therefore an intermediate STATE_PENDING state and memory barriers |
754 | * are necessary. The same algorithm is used for sysv semaphores, see |
755 | * ipc/sem.c fore more details. |
756 | * |
757 | * The same algorithm is used for senders. |
758 | */ |
759 | |
760 | /* pipelined_send() - send a message directly to the task waiting in |
761 | * sys_mq_timedreceive() (without inserting message into a queue). |
762 | */ |
763 | static inline void pipelined_send(struct mqueue_inode_info *info, |
764 | struct msg_msg *message, |
765 | struct ext_wait_queue *receiver) |
766 | { |
767 | receiver->msg = message; |
768 | list_del(&receiver->list); |
769 | receiver->state = STATE_PENDING; |
770 | wake_up_process(receiver->task); |
771 | smp_wmb(); |
772 | receiver->state = STATE_READY; |
773 | } |
774 | |
775 | /* pipelined_receive() - if there is task waiting in sys_mq_timedsend() |
776 | * gets its message and put to the queue (we have one free place for sure). */ |
777 | static inline void pipelined_receive(struct mqueue_inode_info *info) |
778 | { |
779 | struct ext_wait_queue *sender = wq_get_first_waiter(info, SEND); |
780 | |
781 | if (!sender) { |
782 | /* for poll */ |
783 | wake_up_interruptible(&info->wait_q); |
784 | return; |
785 | } |
786 | msg_insert(sender->msg, info); |
787 | list_del(&sender->list); |
788 | sender->state = STATE_PENDING; |
789 | wake_up_process(sender->task); |
790 | smp_wmb(); |
791 | sender->state = STATE_READY; |
792 | } |
793 | |
794 | asmlinkage long sys_mq_timedsend(mqd_t mqdes, const char __user *u_msg_ptr, |
795 | size_t msg_len, unsigned int msg_prio, |
796 | const struct timespec __user *u_abs_timeout) |
797 | { |
798 | struct file *filp; |
799 | struct inode *inode; |
800 | struct ext_wait_queue wait; |
801 | struct ext_wait_queue *receiver; |
802 | struct msg_msg *msg_ptr; |
803 | struct mqueue_inode_info *info; |
804 | long timeout; |
805 | int ret; |
806 | |
807 | if (unlikely(msg_prio >= (unsigned long) MQ_PRIO_MAX)) |
808 | return -EINVAL; |
809 | |
810 | timeout = prepare_timeout(u_abs_timeout); |
811 | |
812 | ret = -EBADF; |
813 | filp = fget(mqdes); |
814 | if (unlikely(!filp)) |
815 | goto out; |
816 | |
817 | inode = filp->f_dentry->d_inode; |
818 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
819 | goto out_fput; |
820 | info = MQUEUE_I(inode); |
821 | |
822 | if (unlikely(!(filp->f_mode & FMODE_WRITE))) |
823 | goto out_fput; |
824 | |
825 | if (unlikely(msg_len > info->attr.mq_msgsize)) { |
826 | ret = -EMSGSIZE; |
827 | goto out_fput; |
828 | } |
829 | |
830 | /* First try to allocate memory, before doing anything with |
831 | * existing queues. */ |
832 | msg_ptr = load_msg(u_msg_ptr, msg_len); |
833 | if (IS_ERR(msg_ptr)) { |
834 | ret = PTR_ERR(msg_ptr); |
835 | goto out_fput; |
836 | } |
837 | msg_ptr->m_ts = msg_len; |
838 | msg_ptr->m_type = msg_prio; |
839 | |
840 | spin_lock(&info->lock); |
841 | |
842 | if (info->attr.mq_curmsgs == info->attr.mq_maxmsg) { |
843 | if (filp->f_flags & O_NONBLOCK) { |
844 | spin_unlock(&info->lock); |
845 | ret = -EAGAIN; |
846 | } else if (unlikely(timeout < 0)) { |
847 | spin_unlock(&info->lock); |
848 | ret = timeout; |
849 | } else { |
850 | wait.task = current; |
851 | wait.msg = (void *) msg_ptr; |
852 | wait.state = STATE_NONE; |
853 | ret = wq_sleep(info, SEND, timeout, &wait); |
854 | } |
855 | if (ret < 0) |
856 | free_msg(msg_ptr); |
857 | } else { |
858 | receiver = wq_get_first_waiter(info, RECV); |
859 | if (receiver) { |
860 | pipelined_send(info, msg_ptr, receiver); |
861 | } else { |
862 | /* adds message to the queue */ |
863 | msg_insert(msg_ptr, info); |
864 | __do_notify(info); |
865 | } |
866 | inode->i_atime = inode->i_mtime = inode->i_ctime = |
867 | CURRENT_TIME; |
868 | spin_unlock(&info->lock); |
869 | ret = 0; |
870 | } |
871 | out_fput: |
872 | fput(filp); |
873 | out: |
874 | return ret; |
875 | } |
876 | |
877 | asmlinkage ssize_t sys_mq_timedreceive(mqd_t mqdes, char __user *u_msg_ptr, |
878 | size_t msg_len, unsigned int __user *u_msg_prio, |
879 | const struct timespec __user *u_abs_timeout) |
880 | { |
881 | long timeout; |
882 | ssize_t ret; |
883 | struct msg_msg *msg_ptr; |
884 | struct file *filp; |
885 | struct inode *inode; |
886 | struct mqueue_inode_info *info; |
887 | struct ext_wait_queue wait; |
888 | |
889 | timeout = prepare_timeout(u_abs_timeout); |
890 | |
891 | ret = -EBADF; |
892 | filp = fget(mqdes); |
893 | if (unlikely(!filp)) |
894 | goto out; |
895 | |
896 | inode = filp->f_dentry->d_inode; |
897 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
898 | goto out_fput; |
899 | info = MQUEUE_I(inode); |
900 | |
901 | if (unlikely(!(filp->f_mode & FMODE_READ))) |
902 | goto out_fput; |
903 | |
904 | /* checks if buffer is big enough */ |
905 | if (unlikely(msg_len < info->attr.mq_msgsize)) { |
906 | ret = -EMSGSIZE; |
907 | goto out_fput; |
908 | } |
909 | |
910 | spin_lock(&info->lock); |
911 | if (info->attr.mq_curmsgs == 0) { |
912 | if (filp->f_flags & O_NONBLOCK) { |
913 | spin_unlock(&info->lock); |
914 | ret = -EAGAIN; |
915 | msg_ptr = NULL; |
916 | } else if (unlikely(timeout < 0)) { |
917 | spin_unlock(&info->lock); |
918 | ret = timeout; |
919 | msg_ptr = NULL; |
920 | } else { |
921 | wait.task = current; |
922 | wait.state = STATE_NONE; |
923 | ret = wq_sleep(info, RECV, timeout, &wait); |
924 | msg_ptr = wait.msg; |
925 | } |
926 | } else { |
927 | msg_ptr = msg_get(info); |
928 | |
929 | inode->i_atime = inode->i_mtime = inode->i_ctime = |
930 | CURRENT_TIME; |
931 | |
932 | /* There is now free space in queue. */ |
933 | pipelined_receive(info); |
934 | spin_unlock(&info->lock); |
935 | ret = 0; |
936 | } |
937 | if (ret == 0) { |
938 | ret = msg_ptr->m_ts; |
939 | |
940 | if ((u_msg_prio && put_user(msg_ptr->m_type, u_msg_prio)) || |
941 | store_msg(u_msg_ptr, msg_ptr, msg_ptr->m_ts)) { |
942 | ret = -EFAULT; |
943 | } |
944 | free_msg(msg_ptr); |
945 | } |
946 | out_fput: |
947 | fput(filp); |
948 | out: |
949 | return ret; |
950 | } |
951 | |
952 | /* |
953 | * Notes: the case when user wants us to deregister (with NULL as pointer) |
954 | * and he isn't currently owner of notification, will be silently discarded. |
955 | * It isn't explicitly defined in the POSIX. |
956 | */ |
957 | asmlinkage long sys_mq_notify(mqd_t mqdes, |
958 | const struct sigevent __user *u_notification) |
959 | { |
960 | int ret; |
961 | struct file *filp; |
962 | struct sock *sock; |
963 | struct inode *inode; |
964 | struct sigevent notification; |
965 | struct mqueue_inode_info *info; |
966 | struct sk_buff *nc; |
967 | |
968 | nc = NULL; |
969 | sock = NULL; |
970 | if (u_notification != NULL) { |
971 | if (copy_from_user(¬ification, u_notification, |
972 | sizeof(struct sigevent))) |
973 | return -EFAULT; |
974 | |
975 | if (unlikely(notification.sigev_notify != SIGEV_NONE && |
976 | notification.sigev_notify != SIGEV_SIGNAL && |
977 | notification.sigev_notify != SIGEV_THREAD)) |
978 | return -EINVAL; |
979 | if (notification.sigev_notify == SIGEV_SIGNAL && |
980 | !valid_signal(notification.sigev_signo)) { |
981 | return -EINVAL; |
982 | } |
983 | if (notification.sigev_notify == SIGEV_THREAD) { |
984 | /* create the notify skb */ |
985 | nc = alloc_skb(NOTIFY_COOKIE_LEN, GFP_KERNEL); |
986 | ret = -ENOMEM; |
987 | if (!nc) |
988 | goto out; |
989 | ret = -EFAULT; |
990 | if (copy_from_user(nc->data, |
991 | notification.sigev_value.sival_ptr, |
992 | NOTIFY_COOKIE_LEN)) { |
993 | goto out; |
994 | } |
995 | |
996 | /* TODO: add a header? */ |
997 | skb_put(nc, NOTIFY_COOKIE_LEN); |
998 | /* and attach it to the socket */ |
999 | retry: |
1000 | filp = fget(notification.sigev_signo); |
1001 | ret = -EBADF; |
1002 | if (!filp) |
1003 | goto out; |
1004 | sock = netlink_getsockbyfilp(filp); |
1005 | fput(filp); |
1006 | if (IS_ERR(sock)) { |
1007 | ret = PTR_ERR(sock); |
1008 | sock = NULL; |
1009 | goto out; |
1010 | } |
1011 | |
1012 | ret = netlink_attachskb(sock, nc, 0, MAX_SCHEDULE_TIMEOUT); |
1013 | if (ret == 1) |
1014 | goto retry; |
1015 | if (ret) { |
1016 | sock = NULL; |
1017 | nc = NULL; |
1018 | goto out; |
1019 | } |
1020 | } |
1021 | } |
1022 | |
1023 | ret = -EBADF; |
1024 | filp = fget(mqdes); |
1025 | if (!filp) |
1026 | goto out; |
1027 | |
1028 | inode = filp->f_dentry->d_inode; |
1029 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
1030 | goto out_fput; |
1031 | info = MQUEUE_I(inode); |
1032 | |
1033 | ret = 0; |
1034 | spin_lock(&info->lock); |
1035 | if (u_notification == NULL) { |
1036 | if (info->notify_owner == current->tgid) { |
1037 | remove_notification(info); |
1038 | inode->i_atime = inode->i_ctime = CURRENT_TIME; |
1039 | } |
1040 | } else if (info->notify_owner != 0) { |
1041 | ret = -EBUSY; |
1042 | } else { |
1043 | switch (notification.sigev_notify) { |
1044 | case SIGEV_NONE: |
1045 | info->notify.sigev_notify = SIGEV_NONE; |
1046 | break; |
1047 | case SIGEV_THREAD: |
1048 | info->notify_sock = sock; |
1049 | info->notify_cookie = nc; |
1050 | sock = NULL; |
1051 | nc = NULL; |
1052 | info->notify.sigev_notify = SIGEV_THREAD; |
1053 | break; |
1054 | case SIGEV_SIGNAL: |
1055 | info->notify.sigev_signo = notification.sigev_signo; |
1056 | info->notify.sigev_value = notification.sigev_value; |
1057 | info->notify.sigev_notify = SIGEV_SIGNAL; |
1058 | break; |
1059 | } |
1060 | info->notify_owner = current->tgid; |
1061 | inode->i_atime = inode->i_ctime = CURRENT_TIME; |
1062 | } |
1063 | spin_unlock(&info->lock); |
1064 | out_fput: |
1065 | fput(filp); |
1066 | out: |
1067 | if (sock) { |
1068 | netlink_detachskb(sock, nc); |
1069 | } else if (nc) { |
1070 | dev_kfree_skb(nc); |
1071 | } |
1072 | return ret; |
1073 | } |
1074 | |
1075 | asmlinkage long sys_mq_getsetattr(mqd_t mqdes, |
1076 | const struct mq_attr __user *u_mqstat, |
1077 | struct mq_attr __user *u_omqstat) |
1078 | { |
1079 | int ret; |
1080 | struct mq_attr mqstat, omqstat; |
1081 | struct file *filp; |
1082 | struct inode *inode; |
1083 | struct mqueue_inode_info *info; |
1084 | |
1085 | if (u_mqstat != NULL) { |
1086 | if (copy_from_user(&mqstat, u_mqstat, sizeof(struct mq_attr))) |
1087 | return -EFAULT; |
1088 | if (mqstat.mq_flags & (~O_NONBLOCK)) |
1089 | return -EINVAL; |
1090 | } |
1091 | |
1092 | ret = -EBADF; |
1093 | filp = fget(mqdes); |
1094 | if (!filp) |
1095 | goto out; |
1096 | |
1097 | inode = filp->f_dentry->d_inode; |
1098 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
1099 | goto out_fput; |
1100 | info = MQUEUE_I(inode); |
1101 | |
1102 | spin_lock(&info->lock); |
1103 | |
1104 | omqstat = info->attr; |
1105 | omqstat.mq_flags = filp->f_flags & O_NONBLOCK; |
1106 | if (u_mqstat) { |
1107 | if (mqstat.mq_flags & O_NONBLOCK) |
1108 | filp->f_flags |= O_NONBLOCK; |
1109 | else |
1110 | filp->f_flags &= ~O_NONBLOCK; |
1111 | |
1112 | inode->i_atime = inode->i_ctime = CURRENT_TIME; |
1113 | } |
1114 | |
1115 | spin_unlock(&info->lock); |
1116 | |
1117 | ret = 0; |
1118 | if (u_omqstat != NULL && copy_to_user(u_omqstat, &omqstat, |
1119 | sizeof(struct mq_attr))) |
1120 | ret = -EFAULT; |
1121 | |
1122 | out_fput: |
1123 | fput(filp); |
1124 | out: |
1125 | return ret; |
1126 | } |
1127 | |
1128 | static struct inode_operations mqueue_dir_inode_operations = { |
1129 | .lookup = simple_lookup, |
1130 | .create = mqueue_create, |
1131 | .unlink = mqueue_unlink, |
1132 | }; |
1133 | |
1134 | static struct file_operations mqueue_file_operations = { |
1135 | .flush = mqueue_flush_file, |
1136 | .poll = mqueue_poll_file, |
1137 | .read = mqueue_read_file, |
1138 | }; |
1139 | |
1140 | static struct super_operations mqueue_super_ops = { |
1141 | .alloc_inode = mqueue_alloc_inode, |
1142 | .destroy_inode = mqueue_destroy_inode, |
1143 | .statfs = simple_statfs, |
1144 | .delete_inode = mqueue_delete_inode, |
1145 | .drop_inode = generic_delete_inode, |
1146 | }; |
1147 | |
1148 | static struct file_system_type mqueue_fs_type = { |
1149 | .name = "mqueue", |
1150 | .get_sb = mqueue_get_sb, |
1151 | .kill_sb = kill_litter_super, |
1152 | }; |
1153 | |
1154 | static int msg_max_limit_min = DFLT_MSGMAX; |
1155 | static int msg_max_limit_max = HARD_MSGMAX; |
1156 | |
1157 | static int msg_maxsize_limit_min = DFLT_MSGSIZEMAX; |
1158 | static int msg_maxsize_limit_max = INT_MAX; |
1159 | |
1160 | static ctl_table mq_sysctls[] = { |
1161 | { |
1162 | .ctl_name = CTL_QUEUESMAX, |
1163 | .procname = "queues_max", |
1164 | .data = &queues_max, |
1165 | .maxlen = sizeof(int), |
1166 | .mode = 0644, |
1167 | .proc_handler = &proc_dointvec, |
1168 | }, |
1169 | { |
1170 | .ctl_name = CTL_MSGMAX, |
1171 | .procname = "msg_max", |
1172 | .data = &msg_max, |
1173 | .maxlen = sizeof(int), |
1174 | .mode = 0644, |
1175 | .proc_handler = &proc_dointvec_minmax, |
1176 | .extra1 = &msg_max_limit_min, |
1177 | .extra2 = &msg_max_limit_max, |
1178 | }, |
1179 | { |
1180 | .ctl_name = CTL_MSGSIZEMAX, |
1181 | .procname = "msgsize_max", |
1182 | .data = &msgsize_max, |
1183 | .maxlen = sizeof(int), |
1184 | .mode = 0644, |
1185 | .proc_handler = &proc_dointvec_minmax, |
1186 | .extra1 = &msg_maxsize_limit_min, |
1187 | .extra2 = &msg_maxsize_limit_max, |
1188 | }, |
1189 | { .ctl_name = 0 } |
1190 | }; |
1191 | |
1192 | static ctl_table mq_sysctl_dir[] = { |
1193 | { |
1194 | .ctl_name = FS_MQUEUE, |
1195 | .procname = "mqueue", |
1196 | .mode = 0555, |
1197 | .child = mq_sysctls, |
1198 | }, |
1199 | { .ctl_name = 0 } |
1200 | }; |
1201 | |
1202 | static ctl_table mq_sysctl_root[] = { |
1203 | { |
1204 | .ctl_name = CTL_FS, |
1205 | .procname = "fs", |
1206 | .mode = 0555, |
1207 | .child = mq_sysctl_dir, |
1208 | }, |
1209 | { .ctl_name = 0 } |
1210 | }; |
1211 | |
1212 | static int __init init_mqueue_fs(void) |
1213 | { |
1214 | int error; |
1215 | |
1216 | mqueue_inode_cachep = kmem_cache_create("mqueue_inode_cache", |
1217 | sizeof(struct mqueue_inode_info), 0, |
1218 | SLAB_HWCACHE_ALIGN, init_once, NULL); |
1219 | if (mqueue_inode_cachep == NULL) |
1220 | return -ENOMEM; |
1221 | |
1222 | /* ignore failues - they are not fatal */ |
1223 | mq_sysctl_table = register_sysctl_table(mq_sysctl_root, 0); |
1224 | |
1225 | error = register_filesystem(&mqueue_fs_type); |
1226 | if (error) |
1227 | goto out_sysctl; |
1228 | |
1229 | if (IS_ERR(mqueue_mnt = kern_mount(&mqueue_fs_type))) { |
1230 | error = PTR_ERR(mqueue_mnt); |
1231 | goto out_filesystem; |
1232 | } |
1233 | |
1234 | /* internal initialization - not common for vfs */ |
1235 | queues_count = 0; |
1236 | spin_lock_init(&mq_lock); |
1237 | |
1238 | return 0; |
1239 | |
1240 | out_filesystem: |
1241 | unregister_filesystem(&mqueue_fs_type); |
1242 | out_sysctl: |
1243 | if (mq_sysctl_table) |
1244 | unregister_sysctl_table(mq_sysctl_table); |
1245 | if (kmem_cache_destroy(mqueue_inode_cachep)) { |
1246 | printk(KERN_INFO |
1247 | "mqueue_inode_cache: not all structures were freed\n"); |
1248 | } |
1249 | return error; |
1250 | } |
1251 | |
1252 | __initcall(init_mqueue_fs); |