Commit | Line | Data |
---|---|---|
1da177e4 LT |
1 | /* |
2 | * POSIX message queues filesystem for Linux. | |
3 | * | |
4 | * Copyright (C) 2003,2004 Krzysztof Benedyczak (golbi@mat.uni.torun.pl) | |
f66e928b | 5 | * Michal Wronski (michal.wronski@gmail.com) |
1da177e4 LT |
6 | * |
7 | * Spinlocks: Mohamed Abbas (abbas.mohamed@intel.com) | |
8 | * Lockless receive & send, fd based notify: | |
9 | * Manfred Spraul (manfred@colorfullife.com) | |
10 | * | |
20ca73bc GW |
11 | * Audit: George Wilson (ltcgcw@us.ibm.com) |
12 | * | |
1da177e4 LT |
13 | * This file is released under the GPL. |
14 | */ | |
15 | ||
c59ede7b | 16 | #include <linux/capability.h> |
1da177e4 LT |
17 | #include <linux/init.h> |
18 | #include <linux/pagemap.h> | |
19 | #include <linux/file.h> | |
20 | #include <linux/mount.h> | |
21 | #include <linux/namei.h> | |
22 | #include <linux/sysctl.h> | |
23 | #include <linux/poll.h> | |
24 | #include <linux/mqueue.h> | |
25 | #include <linux/msg.h> | |
26 | #include <linux/skbuff.h> | |
27 | #include <linux/netlink.h> | |
28 | #include <linux/syscalls.h> | |
20ca73bc | 29 | #include <linux/audit.h> |
7ed20e1a | 30 | #include <linux/signal.h> |
5f921ae9 | 31 | #include <linux/mutex.h> |
b488893a PE |
32 | #include <linux/nsproxy.h> |
33 | #include <linux/pid.h> | |
5f921ae9 | 34 | |
1da177e4 LT |
35 | #include <net/sock.h> |
36 | #include "util.h" | |
37 | ||
38 | #define MQUEUE_MAGIC 0x19800202 | |
39 | #define DIRENT_SIZE 20 | |
40 | #define FILENT_SIZE 80 | |
41 | ||
42 | #define SEND 0 | |
43 | #define RECV 1 | |
44 | ||
45 | #define STATE_NONE 0 | |
46 | #define STATE_PENDING 1 | |
47 | #define STATE_READY 2 | |
48 | ||
1da177e4 LT |
49 | /* default values */ |
50 | #define DFLT_QUEUESMAX 256 /* max number of message queues */ | |
51 | #define DFLT_MSGMAX 10 /* max number of messages in each queue */ | |
52 | #define HARD_MSGMAX (131072/sizeof(void*)) | |
53 | #define DFLT_MSGSIZEMAX 8192 /* max message size */ | |
54 | ||
b231cca4 JK |
55 | /* |
56 | * Define the ranges various user-specified maximum values can | |
57 | * be set to. | |
58 | */ | |
59 | #define MIN_MSGMAX 1 /* min value for msg_max */ | |
60 | #define MAX_MSGMAX HARD_MSGMAX /* max value for msg_max */ | |
61 | #define MIN_MSGSIZEMAX 128 /* min value for msgsize_max */ | |
62 | #define MAX_MSGSIZEMAX (8192*128) /* max value for msgsize_max */ | |
1da177e4 LT |
63 | |
64 | struct ext_wait_queue { /* queue of sleeping tasks */ | |
65 | struct task_struct *task; | |
66 | struct list_head list; | |
67 | struct msg_msg *msg; /* ptr of loaded message */ | |
68 | int state; /* one of STATE_* values */ | |
69 | }; | |
70 | ||
71 | struct mqueue_inode_info { | |
72 | spinlock_t lock; | |
73 | struct inode vfs_inode; | |
74 | wait_queue_head_t wait_q; | |
75 | ||
76 | struct msg_msg **messages; | |
77 | struct mq_attr attr; | |
78 | ||
79 | struct sigevent notify; | |
a03fcb73 | 80 | struct pid* notify_owner; |
338cec32 | 81 | struct user_struct *user; /* user who created, for accounting */ |
1da177e4 LT |
82 | struct sock *notify_sock; |
83 | struct sk_buff *notify_cookie; | |
84 | ||
85 | /* for tasks waiting for free space and messages, respectively */ | |
86 | struct ext_wait_queue e_wait_q[2]; | |
87 | ||
88 | unsigned long qsize; /* size of queue in memory (sum of all msgs) */ | |
89 | }; | |
90 | ||
92e1d5be | 91 | static const struct inode_operations mqueue_dir_inode_operations; |
9a32144e | 92 | static const struct file_operations mqueue_file_operations; |
1da177e4 LT |
93 | static struct super_operations mqueue_super_ops; |
94 | static void remove_notification(struct mqueue_inode_info *info); | |
95 | ||
96 | static spinlock_t mq_lock; | |
e18b890b | 97 | static struct kmem_cache *mqueue_inode_cachep; |
1da177e4 LT |
98 | static struct vfsmount *mqueue_mnt; |
99 | ||
100 | static unsigned int queues_count; | |
101 | static unsigned int queues_max = DFLT_QUEUESMAX; | |
102 | static unsigned int msg_max = DFLT_MSGMAX; | |
103 | static unsigned int msgsize_max = DFLT_MSGSIZEMAX; | |
104 | ||
105 | static struct ctl_table_header * mq_sysctl_table; | |
106 | ||
107 | static inline struct mqueue_inode_info *MQUEUE_I(struct inode *inode) | |
108 | { | |
109 | return container_of(inode, struct mqueue_inode_info, vfs_inode); | |
110 | } | |
111 | ||
112 | static struct inode *mqueue_get_inode(struct super_block *sb, int mode, | |
113 | struct mq_attr *attr) | |
114 | { | |
86a264ab | 115 | struct user_struct *u = current_user(); |
1da177e4 LT |
116 | struct inode *inode; |
117 | ||
118 | inode = new_inode(sb); | |
119 | if (inode) { | |
120 | inode->i_mode = mode; | |
414c0708 DH |
121 | inode->i_uid = current_fsuid(); |
122 | inode->i_gid = current_fsgid(); | |
1da177e4 LT |
123 | inode->i_mtime = inode->i_ctime = inode->i_atime = |
124 | CURRENT_TIME; | |
125 | ||
126 | if (S_ISREG(mode)) { | |
127 | struct mqueue_inode_info *info; | |
128 | struct task_struct *p = current; | |
1da177e4 LT |
129 | unsigned long mq_bytes, mq_msg_tblsz; |
130 | ||
131 | inode->i_fop = &mqueue_file_operations; | |
132 | inode->i_size = FILENT_SIZE; | |
133 | /* mqueue specific info */ | |
134 | info = MQUEUE_I(inode); | |
135 | spin_lock_init(&info->lock); | |
136 | init_waitqueue_head(&info->wait_q); | |
137 | INIT_LIST_HEAD(&info->e_wait_q[0].list); | |
138 | INIT_LIST_HEAD(&info->e_wait_q[1].list); | |
139 | info->messages = NULL; | |
a03fcb73 | 140 | info->notify_owner = NULL; |
1da177e4 LT |
141 | info->qsize = 0; |
142 | info->user = NULL; /* set when all is ok */ | |
143 | memset(&info->attr, 0, sizeof(info->attr)); | |
b231cca4 JK |
144 | info->attr.mq_maxmsg = msg_max; |
145 | info->attr.mq_msgsize = msgsize_max; | |
1da177e4 LT |
146 | if (attr) { |
147 | info->attr.mq_maxmsg = attr->mq_maxmsg; | |
148 | info->attr.mq_msgsize = attr->mq_msgsize; | |
149 | } | |
150 | mq_msg_tblsz = info->attr.mq_maxmsg * sizeof(struct msg_msg *); | |
151 | mq_bytes = (mq_msg_tblsz + | |
152 | (info->attr.mq_maxmsg * info->attr.mq_msgsize)); | |
153 | ||
154 | spin_lock(&mq_lock); | |
155 | if (u->mq_bytes + mq_bytes < u->mq_bytes || | |
156 | u->mq_bytes + mq_bytes > | |
157 | p->signal->rlim[RLIMIT_MSGQUEUE].rlim_cur) { | |
158 | spin_unlock(&mq_lock); | |
159 | goto out_inode; | |
160 | } | |
161 | u->mq_bytes += mq_bytes; | |
162 | spin_unlock(&mq_lock); | |
163 | ||
164 | info->messages = kmalloc(mq_msg_tblsz, GFP_KERNEL); | |
165 | if (!info->messages) { | |
166 | spin_lock(&mq_lock); | |
167 | u->mq_bytes -= mq_bytes; | |
168 | spin_unlock(&mq_lock); | |
169 | goto out_inode; | |
170 | } | |
171 | /* all is ok */ | |
172 | info->user = get_uid(u); | |
173 | } else if (S_ISDIR(mode)) { | |
d8c76e6f | 174 | inc_nlink(inode); |
1da177e4 LT |
175 | /* Some things misbehave if size == 0 on a directory */ |
176 | inode->i_size = 2 * DIRENT_SIZE; | |
177 | inode->i_op = &mqueue_dir_inode_operations; | |
178 | inode->i_fop = &simple_dir_operations; | |
179 | } | |
180 | } | |
181 | return inode; | |
182 | out_inode: | |
183 | make_bad_inode(inode); | |
184 | iput(inode); | |
185 | return NULL; | |
186 | } | |
187 | ||
188 | static int mqueue_fill_super(struct super_block *sb, void *data, int silent) | |
189 | { | |
190 | struct inode *inode; | |
191 | ||
192 | sb->s_blocksize = PAGE_CACHE_SIZE; | |
193 | sb->s_blocksize_bits = PAGE_CACHE_SHIFT; | |
194 | sb->s_magic = MQUEUE_MAGIC; | |
195 | sb->s_op = &mqueue_super_ops; | |
196 | ||
197 | inode = mqueue_get_inode(sb, S_IFDIR | S_ISVTX | S_IRWXUGO, NULL); | |
198 | if (!inode) | |
199 | return -ENOMEM; | |
200 | ||
201 | sb->s_root = d_alloc_root(inode); | |
202 | if (!sb->s_root) { | |
203 | iput(inode); | |
204 | return -ENOMEM; | |
205 | } | |
206 | ||
207 | return 0; | |
208 | } | |
209 | ||
454e2398 DH |
210 | static int mqueue_get_sb(struct file_system_type *fs_type, |
211 | int flags, const char *dev_name, | |
212 | void *data, struct vfsmount *mnt) | |
1da177e4 | 213 | { |
454e2398 | 214 | return get_sb_single(fs_type, flags, data, mqueue_fill_super, mnt); |
1da177e4 LT |
215 | } |
216 | ||
51cc5068 | 217 | static void init_once(void *foo) |
1da177e4 LT |
218 | { |
219 | struct mqueue_inode_info *p = (struct mqueue_inode_info *) foo; | |
220 | ||
a35afb83 | 221 | inode_init_once(&p->vfs_inode); |
1da177e4 LT |
222 | } |
223 | ||
224 | static struct inode *mqueue_alloc_inode(struct super_block *sb) | |
225 | { | |
226 | struct mqueue_inode_info *ei; | |
227 | ||
e94b1766 | 228 | ei = kmem_cache_alloc(mqueue_inode_cachep, GFP_KERNEL); |
1da177e4 LT |
229 | if (!ei) |
230 | return NULL; | |
231 | return &ei->vfs_inode; | |
232 | } | |
233 | ||
234 | static void mqueue_destroy_inode(struct inode *inode) | |
235 | { | |
236 | kmem_cache_free(mqueue_inode_cachep, MQUEUE_I(inode)); | |
237 | } | |
238 | ||
239 | static void mqueue_delete_inode(struct inode *inode) | |
240 | { | |
241 | struct mqueue_inode_info *info; | |
242 | struct user_struct *user; | |
243 | unsigned long mq_bytes; | |
244 | int i; | |
245 | ||
246 | if (S_ISDIR(inode->i_mode)) { | |
247 | clear_inode(inode); | |
248 | return; | |
249 | } | |
250 | info = MQUEUE_I(inode); | |
251 | spin_lock(&info->lock); | |
252 | for (i = 0; i < info->attr.mq_curmsgs; i++) | |
253 | free_msg(info->messages[i]); | |
254 | kfree(info->messages); | |
255 | spin_unlock(&info->lock); | |
256 | ||
257 | clear_inode(inode); | |
258 | ||
259 | mq_bytes = (info->attr.mq_maxmsg * sizeof(struct msg_msg *) + | |
260 | (info->attr.mq_maxmsg * info->attr.mq_msgsize)); | |
261 | user = info->user; | |
262 | if (user) { | |
263 | spin_lock(&mq_lock); | |
264 | user->mq_bytes -= mq_bytes; | |
265 | queues_count--; | |
266 | spin_unlock(&mq_lock); | |
267 | free_uid(user); | |
268 | } | |
269 | } | |
270 | ||
271 | static int mqueue_create(struct inode *dir, struct dentry *dentry, | |
272 | int mode, struct nameidata *nd) | |
273 | { | |
274 | struct inode *inode; | |
275 | struct mq_attr *attr = dentry->d_fsdata; | |
276 | int error; | |
277 | ||
278 | spin_lock(&mq_lock); | |
279 | if (queues_count >= queues_max && !capable(CAP_SYS_RESOURCE)) { | |
280 | error = -ENOSPC; | |
281 | goto out_lock; | |
282 | } | |
283 | queues_count++; | |
284 | spin_unlock(&mq_lock); | |
285 | ||
286 | inode = mqueue_get_inode(dir->i_sb, mode, attr); | |
287 | if (!inode) { | |
288 | error = -ENOMEM; | |
289 | spin_lock(&mq_lock); | |
290 | queues_count--; | |
291 | goto out_lock; | |
292 | } | |
293 | ||
294 | dir->i_size += DIRENT_SIZE; | |
295 | dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME; | |
296 | ||
297 | d_instantiate(dentry, inode); | |
298 | dget(dentry); | |
299 | return 0; | |
300 | out_lock: | |
301 | spin_unlock(&mq_lock); | |
302 | return error; | |
303 | } | |
304 | ||
305 | static int mqueue_unlink(struct inode *dir, struct dentry *dentry) | |
306 | { | |
307 | struct inode *inode = dentry->d_inode; | |
308 | ||
309 | dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME; | |
310 | dir->i_size -= DIRENT_SIZE; | |
9a53c3a7 | 311 | drop_nlink(inode); |
1da177e4 LT |
312 | dput(dentry); |
313 | return 0; | |
314 | } | |
315 | ||
316 | /* | |
317 | * This is routine for system read from queue file. | |
318 | * To avoid mess with doing here some sort of mq_receive we allow | |
319 | * to read only queue size & notification info (the only values | |
320 | * that are interesting from user point of view and aren't accessible | |
321 | * through std routines) | |
322 | */ | |
323 | static ssize_t mqueue_read_file(struct file *filp, char __user *u_data, | |
f1a43f93 | 324 | size_t count, loff_t *off) |
1da177e4 | 325 | { |
6d63079a | 326 | struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode); |
1da177e4 | 327 | char buffer[FILENT_SIZE]; |
f1a43f93 | 328 | ssize_t ret; |
1da177e4 LT |
329 | |
330 | spin_lock(&info->lock); | |
331 | snprintf(buffer, sizeof(buffer), | |
332 | "QSIZE:%-10lu NOTIFY:%-5d SIGNO:%-5d NOTIFY_PID:%-6d\n", | |
333 | info->qsize, | |
334 | info->notify_owner ? info->notify.sigev_notify : 0, | |
335 | (info->notify_owner && | |
336 | info->notify.sigev_notify == SIGEV_SIGNAL) ? | |
337 | info->notify.sigev_signo : 0, | |
6c5f3e7b | 338 | pid_vnr(info->notify_owner)); |
1da177e4 LT |
339 | spin_unlock(&info->lock); |
340 | buffer[sizeof(buffer)-1] = '\0'; | |
1da177e4 | 341 | |
f1a43f93 AM |
342 | ret = simple_read_from_buffer(u_data, count, off, buffer, |
343 | strlen(buffer)); | |
344 | if (ret <= 0) | |
345 | return ret; | |
1da177e4 | 346 | |
6d63079a | 347 | filp->f_path.dentry->d_inode->i_atime = filp->f_path.dentry->d_inode->i_ctime = CURRENT_TIME; |
f1a43f93 | 348 | return ret; |
1da177e4 LT |
349 | } |
350 | ||
75e1fcc0 | 351 | static int mqueue_flush_file(struct file *filp, fl_owner_t id) |
1da177e4 | 352 | { |
6d63079a | 353 | struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode); |
1da177e4 LT |
354 | |
355 | spin_lock(&info->lock); | |
a03fcb73 | 356 | if (task_tgid(current) == info->notify_owner) |
1da177e4 LT |
357 | remove_notification(info); |
358 | ||
359 | spin_unlock(&info->lock); | |
360 | return 0; | |
361 | } | |
362 | ||
363 | static unsigned int mqueue_poll_file(struct file *filp, struct poll_table_struct *poll_tab) | |
364 | { | |
6d63079a | 365 | struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode); |
1da177e4 LT |
366 | int retval = 0; |
367 | ||
368 | poll_wait(filp, &info->wait_q, poll_tab); | |
369 | ||
370 | spin_lock(&info->lock); | |
371 | if (info->attr.mq_curmsgs) | |
372 | retval = POLLIN | POLLRDNORM; | |
373 | ||
374 | if (info->attr.mq_curmsgs < info->attr.mq_maxmsg) | |
375 | retval |= POLLOUT | POLLWRNORM; | |
376 | spin_unlock(&info->lock); | |
377 | ||
378 | return retval; | |
379 | } | |
380 | ||
381 | /* Adds current to info->e_wait_q[sr] before element with smaller prio */ | |
382 | static void wq_add(struct mqueue_inode_info *info, int sr, | |
383 | struct ext_wait_queue *ewp) | |
384 | { | |
385 | struct ext_wait_queue *walk; | |
386 | ||
387 | ewp->task = current; | |
388 | ||
389 | list_for_each_entry(walk, &info->e_wait_q[sr].list, list) { | |
390 | if (walk->task->static_prio <= current->static_prio) { | |
391 | list_add_tail(&ewp->list, &walk->list); | |
392 | return; | |
393 | } | |
394 | } | |
395 | list_add_tail(&ewp->list, &info->e_wait_q[sr].list); | |
396 | } | |
397 | ||
398 | /* | |
399 | * Puts current task to sleep. Caller must hold queue lock. After return | |
400 | * lock isn't held. | |
401 | * sr: SEND or RECV | |
402 | */ | |
403 | static int wq_sleep(struct mqueue_inode_info *info, int sr, | |
404 | long timeout, struct ext_wait_queue *ewp) | |
405 | { | |
406 | int retval; | |
407 | signed long time; | |
408 | ||
409 | wq_add(info, sr, ewp); | |
410 | ||
411 | for (;;) { | |
412 | set_current_state(TASK_INTERRUPTIBLE); | |
413 | ||
414 | spin_unlock(&info->lock); | |
415 | time = schedule_timeout(timeout); | |
416 | ||
417 | while (ewp->state == STATE_PENDING) | |
418 | cpu_relax(); | |
419 | ||
420 | if (ewp->state == STATE_READY) { | |
421 | retval = 0; | |
422 | goto out; | |
423 | } | |
424 | spin_lock(&info->lock); | |
425 | if (ewp->state == STATE_READY) { | |
426 | retval = 0; | |
427 | goto out_unlock; | |
428 | } | |
429 | if (signal_pending(current)) { | |
430 | retval = -ERESTARTSYS; | |
431 | break; | |
432 | } | |
433 | if (time == 0) { | |
434 | retval = -ETIMEDOUT; | |
435 | break; | |
436 | } | |
437 | } | |
438 | list_del(&ewp->list); | |
439 | out_unlock: | |
440 | spin_unlock(&info->lock); | |
441 | out: | |
442 | return retval; | |
443 | } | |
444 | ||
445 | /* | |
446 | * Returns waiting task that should be serviced first or NULL if none exists | |
447 | */ | |
448 | static struct ext_wait_queue *wq_get_first_waiter( | |
449 | struct mqueue_inode_info *info, int sr) | |
450 | { | |
451 | struct list_head *ptr; | |
452 | ||
453 | ptr = info->e_wait_q[sr].list.prev; | |
454 | if (ptr == &info->e_wait_q[sr].list) | |
455 | return NULL; | |
456 | return list_entry(ptr, struct ext_wait_queue, list); | |
457 | } | |
458 | ||
459 | /* Auxiliary functions to manipulate messages' list */ | |
460 | static void msg_insert(struct msg_msg *ptr, struct mqueue_inode_info *info) | |
461 | { | |
462 | int k; | |
463 | ||
464 | k = info->attr.mq_curmsgs - 1; | |
465 | while (k >= 0 && info->messages[k]->m_type >= ptr->m_type) { | |
466 | info->messages[k + 1] = info->messages[k]; | |
467 | k--; | |
468 | } | |
469 | info->attr.mq_curmsgs++; | |
470 | info->qsize += ptr->m_ts; | |
471 | info->messages[k + 1] = ptr; | |
472 | } | |
473 | ||
474 | static inline struct msg_msg *msg_get(struct mqueue_inode_info *info) | |
475 | { | |
476 | info->qsize -= info->messages[--info->attr.mq_curmsgs]->m_ts; | |
477 | return info->messages[info->attr.mq_curmsgs]; | |
478 | } | |
479 | ||
480 | static inline void set_cookie(struct sk_buff *skb, char code) | |
481 | { | |
482 | ((char*)skb->data)[NOTIFY_COOKIE_LEN-1] = code; | |
483 | } | |
484 | ||
485 | /* | |
486 | * The next function is only to split too long sys_mq_timedsend | |
487 | */ | |
488 | static void __do_notify(struct mqueue_inode_info *info) | |
489 | { | |
490 | /* notification | |
491 | * invoked when there is registered process and there isn't process | |
492 | * waiting synchronously for message AND state of queue changed from | |
493 | * empty to not empty. Here we are sure that no one is waiting | |
494 | * synchronously. */ | |
495 | if (info->notify_owner && | |
496 | info->attr.mq_curmsgs == 1) { | |
497 | struct siginfo sig_i; | |
498 | switch (info->notify.sigev_notify) { | |
499 | case SIGEV_NONE: | |
500 | break; | |
501 | case SIGEV_SIGNAL: | |
502 | /* sends signal */ | |
503 | ||
504 | sig_i.si_signo = info->notify.sigev_signo; | |
505 | sig_i.si_errno = 0; | |
506 | sig_i.si_code = SI_MESGQ; | |
507 | sig_i.si_value = info->notify.sigev_value; | |
56496c1d | 508 | sig_i.si_pid = task_tgid_vnr(current); |
414c0708 | 509 | sig_i.si_uid = current_uid(); |
1da177e4 | 510 | |
a03fcb73 CLG |
511 | kill_pid_info(info->notify.sigev_signo, |
512 | &sig_i, info->notify_owner); | |
1da177e4 LT |
513 | break; |
514 | case SIGEV_THREAD: | |
515 | set_cookie(info->notify_cookie, NOTIFY_WOKENUP); | |
7ee015e0 | 516 | netlink_sendskb(info->notify_sock, info->notify_cookie); |
1da177e4 LT |
517 | break; |
518 | } | |
519 | /* after notification unregisters process */ | |
a03fcb73 CLG |
520 | put_pid(info->notify_owner); |
521 | info->notify_owner = NULL; | |
1da177e4 LT |
522 | } |
523 | wake_up(&info->wait_q); | |
524 | } | |
525 | ||
c32c8af4 | 526 | static long prepare_timeout(struct timespec *p) |
1da177e4 | 527 | { |
c32c8af4 | 528 | struct timespec nowts; |
1da177e4 LT |
529 | long timeout; |
530 | ||
c32c8af4 AV |
531 | if (p) { |
532 | if (unlikely(p->tv_nsec < 0 || p->tv_sec < 0 | |
533 | || p->tv_nsec >= NSEC_PER_SEC)) | |
1da177e4 LT |
534 | return -EINVAL; |
535 | nowts = CURRENT_TIME; | |
536 | /* first subtract as jiffies can't be too big */ | |
c32c8af4 AV |
537 | p->tv_sec -= nowts.tv_sec; |
538 | if (p->tv_nsec < nowts.tv_nsec) { | |
539 | p->tv_nsec += NSEC_PER_SEC; | |
540 | p->tv_sec--; | |
1da177e4 | 541 | } |
c32c8af4 AV |
542 | p->tv_nsec -= nowts.tv_nsec; |
543 | if (p->tv_sec < 0) | |
1da177e4 LT |
544 | return 0; |
545 | ||
c32c8af4 | 546 | timeout = timespec_to_jiffies(p) + 1; |
1da177e4 LT |
547 | } else |
548 | return MAX_SCHEDULE_TIMEOUT; | |
549 | ||
550 | return timeout; | |
551 | } | |
552 | ||
553 | static void remove_notification(struct mqueue_inode_info *info) | |
554 | { | |
a03fcb73 | 555 | if (info->notify_owner != NULL && |
1da177e4 LT |
556 | info->notify.sigev_notify == SIGEV_THREAD) { |
557 | set_cookie(info->notify_cookie, NOTIFY_REMOVED); | |
7ee015e0 | 558 | netlink_sendskb(info->notify_sock, info->notify_cookie); |
1da177e4 | 559 | } |
a03fcb73 CLG |
560 | put_pid(info->notify_owner); |
561 | info->notify_owner = NULL; | |
1da177e4 LT |
562 | } |
563 | ||
564 | static int mq_attr_ok(struct mq_attr *attr) | |
565 | { | |
566 | if (attr->mq_maxmsg <= 0 || attr->mq_msgsize <= 0) | |
567 | return 0; | |
568 | if (capable(CAP_SYS_RESOURCE)) { | |
569 | if (attr->mq_maxmsg > HARD_MSGMAX) | |
570 | return 0; | |
571 | } else { | |
572 | if (attr->mq_maxmsg > msg_max || | |
573 | attr->mq_msgsize > msgsize_max) | |
574 | return 0; | |
575 | } | |
576 | /* check for overflow */ | |
577 | if (attr->mq_msgsize > ULONG_MAX/attr->mq_maxmsg) | |
578 | return 0; | |
579 | if ((unsigned long)(attr->mq_maxmsg * attr->mq_msgsize) + | |
580 | (attr->mq_maxmsg * sizeof (struct msg_msg *)) < | |
581 | (unsigned long)(attr->mq_maxmsg * attr->mq_msgsize)) | |
582 | return 0; | |
583 | return 1; | |
584 | } | |
585 | ||
586 | /* | |
587 | * Invoked when creating a new queue via sys_mq_open | |
588 | */ | |
589 | static struct file *do_create(struct dentry *dir, struct dentry *dentry, | |
564f6993 | 590 | int oflag, mode_t mode, struct mq_attr *attr) |
1da177e4 | 591 | { |
745ca247 | 592 | const struct cred *cred = current_cred(); |
4a3fd211 | 593 | struct file *result; |
1da177e4 LT |
594 | int ret; |
595 | ||
564f6993 | 596 | if (attr) { |
7c7dce92 | 597 | ret = -EINVAL; |
564f6993 | 598 | if (!mq_attr_ok(attr)) |
7c7dce92 | 599 | goto out; |
1da177e4 | 600 | /* store for use during create */ |
564f6993 | 601 | dentry->d_fsdata = attr; |
1da177e4 LT |
602 | } |
603 | ||
59175839 | 604 | mode &= ~current->fs->umask; |
4a3fd211 DH |
605 | ret = mnt_want_write(mqueue_mnt); |
606 | if (ret) | |
607 | goto out; | |
1da177e4 LT |
608 | ret = vfs_create(dir->d_inode, dentry, mode, NULL); |
609 | dentry->d_fsdata = NULL; | |
610 | if (ret) | |
4a3fd211 DH |
611 | goto out_drop_write; |
612 | ||
745ca247 | 613 | result = dentry_open(dentry, mqueue_mnt, oflag, cred); |
4a3fd211 DH |
614 | /* |
615 | * dentry_open() took a persistent mnt_want_write(), | |
616 | * so we can now drop this one. | |
617 | */ | |
618 | mnt_drop_write(mqueue_mnt); | |
619 | return result; | |
620 | ||
621 | out_drop_write: | |
622 | mnt_drop_write(mqueue_mnt); | |
7c7dce92 AV |
623 | out: |
624 | dput(dentry); | |
625 | mntput(mqueue_mnt); | |
626 | return ERR_PTR(ret); | |
1da177e4 LT |
627 | } |
628 | ||
629 | /* Opens existing queue */ | |
630 | static struct file *do_open(struct dentry *dentry, int oflag) | |
631 | { | |
745ca247 DH |
632 | const struct cred *cred = current_cred(); |
633 | ||
634 | static const int oflag2acc[O_ACCMODE] = { MAY_READ, MAY_WRITE, | |
635 | MAY_READ | MAY_WRITE }; | |
1da177e4 | 636 | |
7c7dce92 AV |
637 | if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY)) { |
638 | dput(dentry); | |
639 | mntput(mqueue_mnt); | |
1da177e4 | 640 | return ERR_PTR(-EINVAL); |
7c7dce92 | 641 | } |
1da177e4 | 642 | |
f419a2e3 | 643 | if (inode_permission(dentry->d_inode, oflag2acc[oflag & O_ACCMODE])) { |
7c7dce92 AV |
644 | dput(dentry); |
645 | mntput(mqueue_mnt); | |
1da177e4 | 646 | return ERR_PTR(-EACCES); |
7c7dce92 | 647 | } |
1da177e4 | 648 | |
745ca247 | 649 | return dentry_open(dentry, mqueue_mnt, oflag, cred); |
1da177e4 LT |
650 | } |
651 | ||
652 | asmlinkage long sys_mq_open(const char __user *u_name, int oflag, mode_t mode, | |
653 | struct mq_attr __user *u_attr) | |
654 | { | |
655 | struct dentry *dentry; | |
656 | struct file *filp; | |
657 | char *name; | |
564f6993 | 658 | struct mq_attr attr; |
1da177e4 LT |
659 | int fd, error; |
660 | ||
564f6993 AV |
661 | if (u_attr && copy_from_user(&attr, u_attr, sizeof(struct mq_attr))) |
662 | return -EFAULT; | |
663 | ||
664 | audit_mq_open(oflag, mode, u_attr ? &attr : NULL); | |
20ca73bc | 665 | |
1da177e4 LT |
666 | if (IS_ERR(name = getname(u_name))) |
667 | return PTR_ERR(name); | |
668 | ||
269f2134 | 669 | fd = get_unused_fd_flags(O_CLOEXEC); |
1da177e4 LT |
670 | if (fd < 0) |
671 | goto out_putname; | |
672 | ||
1b1dcc1b | 673 | mutex_lock(&mqueue_mnt->mnt_root->d_inode->i_mutex); |
1da177e4 LT |
674 | dentry = lookup_one_len(name, mqueue_mnt->mnt_root, strlen(name)); |
675 | if (IS_ERR(dentry)) { | |
676 | error = PTR_ERR(dentry); | |
677 | goto out_err; | |
678 | } | |
679 | mntget(mqueue_mnt); | |
680 | ||
681 | if (oflag & O_CREAT) { | |
682 | if (dentry->d_inode) { /* entry already exists */ | |
5a190ae6 | 683 | audit_inode(name, dentry); |
7c7dce92 AV |
684 | error = -EEXIST; |
685 | if (oflag & O_EXCL) | |
686 | goto out; | |
687 | filp = do_open(dentry, oflag); | |
1da177e4 LT |
688 | } else { |
689 | filp = do_create(mqueue_mnt->mnt_root, dentry, | |
564f6993 AV |
690 | oflag, mode, |
691 | u_attr ? &attr : NULL); | |
1da177e4 | 692 | } |
7c7dce92 AV |
693 | } else { |
694 | error = -ENOENT; | |
695 | if (!dentry->d_inode) | |
696 | goto out; | |
5a190ae6 | 697 | audit_inode(name, dentry); |
7c7dce92 AV |
698 | filp = do_open(dentry, oflag); |
699 | } | |
1da177e4 LT |
700 | |
701 | if (IS_ERR(filp)) { | |
702 | error = PTR_ERR(filp); | |
703 | goto out_putfd; | |
704 | } | |
705 | ||
1da177e4 LT |
706 | fd_install(fd, filp); |
707 | goto out_upsem; | |
708 | ||
7c7dce92 AV |
709 | out: |
710 | dput(dentry); | |
1da177e4 | 711 | mntput(mqueue_mnt); |
7c7dce92 | 712 | out_putfd: |
1da177e4 LT |
713 | put_unused_fd(fd); |
714 | out_err: | |
715 | fd = error; | |
716 | out_upsem: | |
1b1dcc1b | 717 | mutex_unlock(&mqueue_mnt->mnt_root->d_inode->i_mutex); |
1da177e4 LT |
718 | out_putname: |
719 | putname(name); | |
720 | return fd; | |
721 | } | |
722 | ||
723 | asmlinkage long sys_mq_unlink(const char __user *u_name) | |
724 | { | |
725 | int err; | |
726 | char *name; | |
727 | struct dentry *dentry; | |
728 | struct inode *inode = NULL; | |
729 | ||
730 | name = getname(u_name); | |
731 | if (IS_ERR(name)) | |
732 | return PTR_ERR(name); | |
733 | ||
7a434814 PZ |
734 | mutex_lock_nested(&mqueue_mnt->mnt_root->d_inode->i_mutex, |
735 | I_MUTEX_PARENT); | |
1da177e4 LT |
736 | dentry = lookup_one_len(name, mqueue_mnt->mnt_root, strlen(name)); |
737 | if (IS_ERR(dentry)) { | |
738 | err = PTR_ERR(dentry); | |
739 | goto out_unlock; | |
740 | } | |
741 | ||
742 | if (!dentry->d_inode) { | |
743 | err = -ENOENT; | |
744 | goto out_err; | |
745 | } | |
746 | ||
747 | inode = dentry->d_inode; | |
748 | if (inode) | |
749 | atomic_inc(&inode->i_count); | |
0622753b DH |
750 | err = mnt_want_write(mqueue_mnt); |
751 | if (err) | |
752 | goto out_err; | |
1da177e4 | 753 | err = vfs_unlink(dentry->d_parent->d_inode, dentry); |
0622753b | 754 | mnt_drop_write(mqueue_mnt); |
1da177e4 LT |
755 | out_err: |
756 | dput(dentry); | |
757 | ||
758 | out_unlock: | |
1b1dcc1b | 759 | mutex_unlock(&mqueue_mnt->mnt_root->d_inode->i_mutex); |
1da177e4 LT |
760 | putname(name); |
761 | if (inode) | |
762 | iput(inode); | |
763 | ||
764 | return err; | |
765 | } | |
766 | ||
767 | /* Pipelined send and receive functions. | |
768 | * | |
769 | * If a receiver finds no waiting message, then it registers itself in the | |
770 | * list of waiting receivers. A sender checks that list before adding the new | |
771 | * message into the message array. If there is a waiting receiver, then it | |
772 | * bypasses the message array and directly hands the message over to the | |
773 | * receiver. | |
774 | * The receiver accepts the message and returns without grabbing the queue | |
775 | * spinlock. Therefore an intermediate STATE_PENDING state and memory barriers | |
776 | * are necessary. The same algorithm is used for sysv semaphores, see | |
7b7a317c | 777 | * ipc/sem.c for more details. |
1da177e4 LT |
778 | * |
779 | * The same algorithm is used for senders. | |
780 | */ | |
781 | ||
782 | /* pipelined_send() - send a message directly to the task waiting in | |
783 | * sys_mq_timedreceive() (without inserting message into a queue). | |
784 | */ | |
785 | static inline void pipelined_send(struct mqueue_inode_info *info, | |
786 | struct msg_msg *message, | |
787 | struct ext_wait_queue *receiver) | |
788 | { | |
789 | receiver->msg = message; | |
790 | list_del(&receiver->list); | |
791 | receiver->state = STATE_PENDING; | |
792 | wake_up_process(receiver->task); | |
d59dd462 | 793 | smp_wmb(); |
1da177e4 LT |
794 | receiver->state = STATE_READY; |
795 | } | |
796 | ||
797 | /* pipelined_receive() - if there is task waiting in sys_mq_timedsend() | |
798 | * gets its message and put to the queue (we have one free place for sure). */ | |
799 | static inline void pipelined_receive(struct mqueue_inode_info *info) | |
800 | { | |
801 | struct ext_wait_queue *sender = wq_get_first_waiter(info, SEND); | |
802 | ||
803 | if (!sender) { | |
804 | /* for poll */ | |
805 | wake_up_interruptible(&info->wait_q); | |
806 | return; | |
807 | } | |
808 | msg_insert(sender->msg, info); | |
809 | list_del(&sender->list); | |
810 | sender->state = STATE_PENDING; | |
811 | wake_up_process(sender->task); | |
d59dd462 | 812 | smp_wmb(); |
1da177e4 LT |
813 | sender->state = STATE_READY; |
814 | } | |
815 | ||
816 | asmlinkage long sys_mq_timedsend(mqd_t mqdes, const char __user *u_msg_ptr, | |
817 | size_t msg_len, unsigned int msg_prio, | |
818 | const struct timespec __user *u_abs_timeout) | |
819 | { | |
820 | struct file *filp; | |
821 | struct inode *inode; | |
822 | struct ext_wait_queue wait; | |
823 | struct ext_wait_queue *receiver; | |
824 | struct msg_msg *msg_ptr; | |
825 | struct mqueue_inode_info *info; | |
c32c8af4 | 826 | struct timespec ts, *p = NULL; |
1da177e4 LT |
827 | long timeout; |
828 | int ret; | |
829 | ||
c32c8af4 AV |
830 | if (u_abs_timeout) { |
831 | if (copy_from_user(&ts, u_abs_timeout, | |
832 | sizeof(struct timespec))) | |
833 | return -EFAULT; | |
834 | p = &ts; | |
835 | } | |
20ca73bc | 836 | |
1da177e4 LT |
837 | if (unlikely(msg_prio >= (unsigned long) MQ_PRIO_MAX)) |
838 | return -EINVAL; | |
839 | ||
c32c8af4 AV |
840 | audit_mq_sendrecv(mqdes, msg_len, msg_prio, p); |
841 | timeout = prepare_timeout(p); | |
1da177e4 LT |
842 | |
843 | ret = -EBADF; | |
844 | filp = fget(mqdes); | |
845 | if (unlikely(!filp)) | |
846 | goto out; | |
847 | ||
6d63079a | 848 | inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
849 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
850 | goto out_fput; | |
851 | info = MQUEUE_I(inode); | |
5a190ae6 | 852 | audit_inode(NULL, filp->f_path.dentry); |
1da177e4 LT |
853 | |
854 | if (unlikely(!(filp->f_mode & FMODE_WRITE))) | |
855 | goto out_fput; | |
856 | ||
857 | if (unlikely(msg_len > info->attr.mq_msgsize)) { | |
858 | ret = -EMSGSIZE; | |
859 | goto out_fput; | |
860 | } | |
861 | ||
862 | /* First try to allocate memory, before doing anything with | |
863 | * existing queues. */ | |
864 | msg_ptr = load_msg(u_msg_ptr, msg_len); | |
865 | if (IS_ERR(msg_ptr)) { | |
866 | ret = PTR_ERR(msg_ptr); | |
867 | goto out_fput; | |
868 | } | |
869 | msg_ptr->m_ts = msg_len; | |
870 | msg_ptr->m_type = msg_prio; | |
871 | ||
872 | spin_lock(&info->lock); | |
873 | ||
874 | if (info->attr.mq_curmsgs == info->attr.mq_maxmsg) { | |
875 | if (filp->f_flags & O_NONBLOCK) { | |
876 | spin_unlock(&info->lock); | |
877 | ret = -EAGAIN; | |
878 | } else if (unlikely(timeout < 0)) { | |
879 | spin_unlock(&info->lock); | |
880 | ret = timeout; | |
881 | } else { | |
882 | wait.task = current; | |
883 | wait.msg = (void *) msg_ptr; | |
884 | wait.state = STATE_NONE; | |
885 | ret = wq_sleep(info, SEND, timeout, &wait); | |
886 | } | |
887 | if (ret < 0) | |
888 | free_msg(msg_ptr); | |
889 | } else { | |
890 | receiver = wq_get_first_waiter(info, RECV); | |
891 | if (receiver) { | |
892 | pipelined_send(info, msg_ptr, receiver); | |
893 | } else { | |
894 | /* adds message to the queue */ | |
895 | msg_insert(msg_ptr, info); | |
896 | __do_notify(info); | |
897 | } | |
898 | inode->i_atime = inode->i_mtime = inode->i_ctime = | |
899 | CURRENT_TIME; | |
900 | spin_unlock(&info->lock); | |
901 | ret = 0; | |
902 | } | |
903 | out_fput: | |
904 | fput(filp); | |
905 | out: | |
906 | return ret; | |
907 | } | |
908 | ||
909 | asmlinkage ssize_t sys_mq_timedreceive(mqd_t mqdes, char __user *u_msg_ptr, | |
910 | size_t msg_len, unsigned int __user *u_msg_prio, | |
911 | const struct timespec __user *u_abs_timeout) | |
912 | { | |
913 | long timeout; | |
914 | ssize_t ret; | |
915 | struct msg_msg *msg_ptr; | |
916 | struct file *filp; | |
917 | struct inode *inode; | |
918 | struct mqueue_inode_info *info; | |
919 | struct ext_wait_queue wait; | |
c32c8af4 | 920 | struct timespec ts, *p = NULL; |
1da177e4 | 921 | |
c32c8af4 AV |
922 | if (u_abs_timeout) { |
923 | if (copy_from_user(&ts, u_abs_timeout, | |
924 | sizeof(struct timespec))) | |
925 | return -EFAULT; | |
926 | p = &ts; | |
927 | } | |
20ca73bc | 928 | |
c32c8af4 AV |
929 | audit_mq_sendrecv(mqdes, msg_len, 0, p); |
930 | timeout = prepare_timeout(p); | |
1da177e4 LT |
931 | |
932 | ret = -EBADF; | |
933 | filp = fget(mqdes); | |
934 | if (unlikely(!filp)) | |
935 | goto out; | |
936 | ||
6d63079a | 937 | inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
938 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
939 | goto out_fput; | |
940 | info = MQUEUE_I(inode); | |
5a190ae6 | 941 | audit_inode(NULL, filp->f_path.dentry); |
1da177e4 LT |
942 | |
943 | if (unlikely(!(filp->f_mode & FMODE_READ))) | |
944 | goto out_fput; | |
945 | ||
946 | /* checks if buffer is big enough */ | |
947 | if (unlikely(msg_len < info->attr.mq_msgsize)) { | |
948 | ret = -EMSGSIZE; | |
949 | goto out_fput; | |
950 | } | |
951 | ||
952 | spin_lock(&info->lock); | |
953 | if (info->attr.mq_curmsgs == 0) { | |
954 | if (filp->f_flags & O_NONBLOCK) { | |
955 | spin_unlock(&info->lock); | |
956 | ret = -EAGAIN; | |
957 | msg_ptr = NULL; | |
958 | } else if (unlikely(timeout < 0)) { | |
959 | spin_unlock(&info->lock); | |
960 | ret = timeout; | |
961 | msg_ptr = NULL; | |
962 | } else { | |
963 | wait.task = current; | |
964 | wait.state = STATE_NONE; | |
965 | ret = wq_sleep(info, RECV, timeout, &wait); | |
966 | msg_ptr = wait.msg; | |
967 | } | |
968 | } else { | |
969 | msg_ptr = msg_get(info); | |
970 | ||
971 | inode->i_atime = inode->i_mtime = inode->i_ctime = | |
972 | CURRENT_TIME; | |
973 | ||
974 | /* There is now free space in queue. */ | |
975 | pipelined_receive(info); | |
976 | spin_unlock(&info->lock); | |
977 | ret = 0; | |
978 | } | |
979 | if (ret == 0) { | |
980 | ret = msg_ptr->m_ts; | |
981 | ||
982 | if ((u_msg_prio && put_user(msg_ptr->m_type, u_msg_prio)) || | |
983 | store_msg(u_msg_ptr, msg_ptr, msg_ptr->m_ts)) { | |
984 | ret = -EFAULT; | |
985 | } | |
986 | free_msg(msg_ptr); | |
987 | } | |
988 | out_fput: | |
989 | fput(filp); | |
990 | out: | |
991 | return ret; | |
992 | } | |
993 | ||
994 | /* | |
995 | * Notes: the case when user wants us to deregister (with NULL as pointer) | |
996 | * and he isn't currently owner of notification, will be silently discarded. | |
997 | * It isn't explicitly defined in the POSIX. | |
998 | */ | |
999 | asmlinkage long sys_mq_notify(mqd_t mqdes, | |
1000 | const struct sigevent __user *u_notification) | |
1001 | { | |
1002 | int ret; | |
1003 | struct file *filp; | |
1004 | struct sock *sock; | |
1005 | struct inode *inode; | |
1006 | struct sigevent notification; | |
1007 | struct mqueue_inode_info *info; | |
1008 | struct sk_buff *nc; | |
1009 | ||
20114f71 | 1010 | if (u_notification) { |
1da177e4 LT |
1011 | if (copy_from_user(¬ification, u_notification, |
1012 | sizeof(struct sigevent))) | |
1013 | return -EFAULT; | |
20114f71 AV |
1014 | } |
1015 | ||
1016 | audit_mq_notify(mqdes, u_notification ? ¬ification : NULL); | |
1da177e4 | 1017 | |
20114f71 AV |
1018 | nc = NULL; |
1019 | sock = NULL; | |
1020 | if (u_notification != NULL) { | |
1da177e4 LT |
1021 | if (unlikely(notification.sigev_notify != SIGEV_NONE && |
1022 | notification.sigev_notify != SIGEV_SIGNAL && | |
1023 | notification.sigev_notify != SIGEV_THREAD)) | |
1024 | return -EINVAL; | |
1025 | if (notification.sigev_notify == SIGEV_SIGNAL && | |
7ed20e1a | 1026 | !valid_signal(notification.sigev_signo)) { |
1da177e4 LT |
1027 | return -EINVAL; |
1028 | } | |
1029 | if (notification.sigev_notify == SIGEV_THREAD) { | |
c3d8d1e3 PM |
1030 | long timeo; |
1031 | ||
1da177e4 LT |
1032 | /* create the notify skb */ |
1033 | nc = alloc_skb(NOTIFY_COOKIE_LEN, GFP_KERNEL); | |
1034 | ret = -ENOMEM; | |
1035 | if (!nc) | |
1036 | goto out; | |
1037 | ret = -EFAULT; | |
1038 | if (copy_from_user(nc->data, | |
1039 | notification.sigev_value.sival_ptr, | |
1040 | NOTIFY_COOKIE_LEN)) { | |
1041 | goto out; | |
1042 | } | |
1043 | ||
1044 | /* TODO: add a header? */ | |
1045 | skb_put(nc, NOTIFY_COOKIE_LEN); | |
1046 | /* and attach it to the socket */ | |
1047 | retry: | |
1048 | filp = fget(notification.sigev_signo); | |
1049 | ret = -EBADF; | |
1050 | if (!filp) | |
1051 | goto out; | |
1052 | sock = netlink_getsockbyfilp(filp); | |
1053 | fput(filp); | |
1054 | if (IS_ERR(sock)) { | |
1055 | ret = PTR_ERR(sock); | |
1056 | sock = NULL; | |
1057 | goto out; | |
1058 | } | |
1059 | ||
c3d8d1e3 | 1060 | timeo = MAX_SCHEDULE_TIMEOUT; |
9457afee | 1061 | ret = netlink_attachskb(sock, nc, &timeo, NULL); |
1da177e4 LT |
1062 | if (ret == 1) |
1063 | goto retry; | |
1064 | if (ret) { | |
1065 | sock = NULL; | |
1066 | nc = NULL; | |
1067 | goto out; | |
1068 | } | |
1069 | } | |
1070 | } | |
1071 | ||
1072 | ret = -EBADF; | |
1073 | filp = fget(mqdes); | |
1074 | if (!filp) | |
1075 | goto out; | |
1076 | ||
6d63079a | 1077 | inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
1078 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
1079 | goto out_fput; | |
1080 | info = MQUEUE_I(inode); | |
1081 | ||
1082 | ret = 0; | |
1083 | spin_lock(&info->lock); | |
1084 | if (u_notification == NULL) { | |
a03fcb73 | 1085 | if (info->notify_owner == task_tgid(current)) { |
1da177e4 LT |
1086 | remove_notification(info); |
1087 | inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
1088 | } | |
a03fcb73 | 1089 | } else if (info->notify_owner != NULL) { |
1da177e4 LT |
1090 | ret = -EBUSY; |
1091 | } else { | |
1092 | switch (notification.sigev_notify) { | |
1093 | case SIGEV_NONE: | |
1094 | info->notify.sigev_notify = SIGEV_NONE; | |
1095 | break; | |
1096 | case SIGEV_THREAD: | |
1097 | info->notify_sock = sock; | |
1098 | info->notify_cookie = nc; | |
1099 | sock = NULL; | |
1100 | nc = NULL; | |
1101 | info->notify.sigev_notify = SIGEV_THREAD; | |
1102 | break; | |
1103 | case SIGEV_SIGNAL: | |
1104 | info->notify.sigev_signo = notification.sigev_signo; | |
1105 | info->notify.sigev_value = notification.sigev_value; | |
1106 | info->notify.sigev_notify = SIGEV_SIGNAL; | |
1107 | break; | |
1108 | } | |
a03fcb73 CLG |
1109 | |
1110 | info->notify_owner = get_pid(task_tgid(current)); | |
1da177e4 LT |
1111 | inode->i_atime = inode->i_ctime = CURRENT_TIME; |
1112 | } | |
1113 | spin_unlock(&info->lock); | |
1114 | out_fput: | |
1115 | fput(filp); | |
1116 | out: | |
1117 | if (sock) { | |
1118 | netlink_detachskb(sock, nc); | |
1119 | } else if (nc) { | |
1120 | dev_kfree_skb(nc); | |
1121 | } | |
1122 | return ret; | |
1123 | } | |
1124 | ||
1125 | asmlinkage long sys_mq_getsetattr(mqd_t mqdes, | |
1126 | const struct mq_attr __user *u_mqstat, | |
1127 | struct mq_attr __user *u_omqstat) | |
1128 | { | |
1129 | int ret; | |
1130 | struct mq_attr mqstat, omqstat; | |
1131 | struct file *filp; | |
1132 | struct inode *inode; | |
1133 | struct mqueue_inode_info *info; | |
1134 | ||
1135 | if (u_mqstat != NULL) { | |
1136 | if (copy_from_user(&mqstat, u_mqstat, sizeof(struct mq_attr))) | |
1137 | return -EFAULT; | |
1138 | if (mqstat.mq_flags & (~O_NONBLOCK)) | |
1139 | return -EINVAL; | |
1140 | } | |
1141 | ||
1142 | ret = -EBADF; | |
1143 | filp = fget(mqdes); | |
1144 | if (!filp) | |
1145 | goto out; | |
1146 | ||
6d63079a | 1147 | inode = filp->f_path.dentry->d_inode; |
1da177e4 LT |
1148 | if (unlikely(filp->f_op != &mqueue_file_operations)) |
1149 | goto out_fput; | |
1150 | info = MQUEUE_I(inode); | |
1151 | ||
1152 | spin_lock(&info->lock); | |
1153 | ||
1154 | omqstat = info->attr; | |
1155 | omqstat.mq_flags = filp->f_flags & O_NONBLOCK; | |
1156 | if (u_mqstat) { | |
7392906e | 1157 | audit_mq_getsetattr(mqdes, &mqstat); |
1da177e4 LT |
1158 | if (mqstat.mq_flags & O_NONBLOCK) |
1159 | filp->f_flags |= O_NONBLOCK; | |
1160 | else | |
1161 | filp->f_flags &= ~O_NONBLOCK; | |
1162 | ||
1163 | inode->i_atime = inode->i_ctime = CURRENT_TIME; | |
1164 | } | |
1165 | ||
1166 | spin_unlock(&info->lock); | |
1167 | ||
1168 | ret = 0; | |
1169 | if (u_omqstat != NULL && copy_to_user(u_omqstat, &omqstat, | |
1170 | sizeof(struct mq_attr))) | |
1171 | ret = -EFAULT; | |
1172 | ||
1173 | out_fput: | |
1174 | fput(filp); | |
1175 | out: | |
1176 | return ret; | |
1177 | } | |
1178 | ||
92e1d5be | 1179 | static const struct inode_operations mqueue_dir_inode_operations = { |
1da177e4 LT |
1180 | .lookup = simple_lookup, |
1181 | .create = mqueue_create, | |
1182 | .unlink = mqueue_unlink, | |
1183 | }; | |
1184 | ||
9a32144e | 1185 | static const struct file_operations mqueue_file_operations = { |
1da177e4 LT |
1186 | .flush = mqueue_flush_file, |
1187 | .poll = mqueue_poll_file, | |
1188 | .read = mqueue_read_file, | |
1189 | }; | |
1190 | ||
1191 | static struct super_operations mqueue_super_ops = { | |
1192 | .alloc_inode = mqueue_alloc_inode, | |
1193 | .destroy_inode = mqueue_destroy_inode, | |
1194 | .statfs = simple_statfs, | |
1195 | .delete_inode = mqueue_delete_inode, | |
1196 | .drop_inode = generic_delete_inode, | |
1197 | }; | |
1198 | ||
1199 | static struct file_system_type mqueue_fs_type = { | |
1200 | .name = "mqueue", | |
1201 | .get_sb = mqueue_get_sb, | |
1202 | .kill_sb = kill_litter_super, | |
1203 | }; | |
1204 | ||
b231cca4 JK |
1205 | static int msg_max_limit_min = MIN_MSGMAX; |
1206 | static int msg_max_limit_max = MAX_MSGMAX; | |
1da177e4 | 1207 | |
b231cca4 JK |
1208 | static int msg_maxsize_limit_min = MIN_MSGSIZEMAX; |
1209 | static int msg_maxsize_limit_max = MAX_MSGSIZEMAX; | |
1da177e4 LT |
1210 | |
1211 | static ctl_table mq_sysctls[] = { | |
1212 | { | |
1da177e4 LT |
1213 | .procname = "queues_max", |
1214 | .data = &queues_max, | |
1215 | .maxlen = sizeof(int), | |
1216 | .mode = 0644, | |
1217 | .proc_handler = &proc_dointvec, | |
1218 | }, | |
1219 | { | |
1da177e4 LT |
1220 | .procname = "msg_max", |
1221 | .data = &msg_max, | |
1222 | .maxlen = sizeof(int), | |
1223 | .mode = 0644, | |
1224 | .proc_handler = &proc_dointvec_minmax, | |
1225 | .extra1 = &msg_max_limit_min, | |
1226 | .extra2 = &msg_max_limit_max, | |
1227 | }, | |
1228 | { | |
1da177e4 LT |
1229 | .procname = "msgsize_max", |
1230 | .data = &msgsize_max, | |
1231 | .maxlen = sizeof(int), | |
1232 | .mode = 0644, | |
1233 | .proc_handler = &proc_dointvec_minmax, | |
1234 | .extra1 = &msg_maxsize_limit_min, | |
1235 | .extra2 = &msg_maxsize_limit_max, | |
1236 | }, | |
1237 | { .ctl_name = 0 } | |
1238 | }; | |
1239 | ||
1240 | static ctl_table mq_sysctl_dir[] = { | |
1241 | { | |
1da177e4 LT |
1242 | .procname = "mqueue", |
1243 | .mode = 0555, | |
1244 | .child = mq_sysctls, | |
1245 | }, | |
1246 | { .ctl_name = 0 } | |
1247 | }; | |
1248 | ||
1249 | static ctl_table mq_sysctl_root[] = { | |
1250 | { | |
1251 | .ctl_name = CTL_FS, | |
1252 | .procname = "fs", | |
1253 | .mode = 0555, | |
1254 | .child = mq_sysctl_dir, | |
1255 | }, | |
1256 | { .ctl_name = 0 } | |
1257 | }; | |
1258 | ||
1259 | static int __init init_mqueue_fs(void) | |
1260 | { | |
1261 | int error; | |
1262 | ||
1263 | mqueue_inode_cachep = kmem_cache_create("mqueue_inode_cache", | |
1264 | sizeof(struct mqueue_inode_info), 0, | |
20c2df83 | 1265 | SLAB_HWCACHE_ALIGN, init_once); |
1da177e4 LT |
1266 | if (mqueue_inode_cachep == NULL) |
1267 | return -ENOMEM; | |
1268 | ||
1269 | /* ignore failues - they are not fatal */ | |
0b4d4147 | 1270 | mq_sysctl_table = register_sysctl_table(mq_sysctl_root); |
1da177e4 LT |
1271 | |
1272 | error = register_filesystem(&mqueue_fs_type); | |
1273 | if (error) | |
1274 | goto out_sysctl; | |
1275 | ||
1276 | if (IS_ERR(mqueue_mnt = kern_mount(&mqueue_fs_type))) { | |
1277 | error = PTR_ERR(mqueue_mnt); | |
1278 | goto out_filesystem; | |
1279 | } | |
1280 | ||
1281 | /* internal initialization - not common for vfs */ | |
1282 | queues_count = 0; | |
1283 | spin_lock_init(&mq_lock); | |
1284 | ||
1285 | return 0; | |
1286 | ||
1287 | out_filesystem: | |
1288 | unregister_filesystem(&mqueue_fs_type); | |
1289 | out_sysctl: | |
1290 | if (mq_sysctl_table) | |
1291 | unregister_sysctl_table(mq_sysctl_table); | |
1a1d92c1 | 1292 | kmem_cache_destroy(mqueue_inode_cachep); |
1da177e4 LT |
1293 | return error; |
1294 | } | |
1295 | ||
1296 | __initcall(init_mqueue_fs); |