blob: 9a142a290749f2af819c47ac487f2192c6502675 [file] [log] [blame]
Linus Torvalds1da177e2005-04-16 15:20:36 -07001/*
2 * POSIX message queues filesystem for Linux.
3 *
4 * Copyright (C) 2003,2004 Krzysztof Benedyczak (golbi@mat.uni.torun.pl)
Michal Wronskif66e9282006-10-03 23:23:27 +02005 * Michal Wronski (michal.wronski@gmail.com)
Linus Torvalds1da177e2005-04-16 15:20:36 -07006 *
7 * Spinlocks: Mohamed Abbas (abbas.mohamed@intel.com)
8 * Lockless receive & send, fd based notify:
9 * Manfred Spraul (manfred@colorfullife.com)
10 *
George C. Wilson20ca73b2006-05-24 16:09:55 -050011 * Audit: George Wilson (ltcgcw@us.ibm.com)
12 *
Linus Torvalds1da177e2005-04-16 15:20:36 -070013 * This file is released under the GPL.
14 */
15
Randy.Dunlapc59ede72006-01-11 12:17:46 -080016#include <linux/capability.h>
Linus Torvalds1da177e2005-04-16 15:20:36 -070017#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>
George C. Wilson20ca73b2006-05-24 16:09:55 -050029#include <linux/audit.h>
Jesper Juhl7ed20e12005-05-01 08:59:14 -070030#include <linux/signal.h>
Ingo Molnar5f921ae2006-03-26 01:37:17 -080031#include <linux/mutex.h>
Pavel Emelyanovb4888932007-10-18 23:40:14 -070032#include <linux/nsproxy.h>
33#include <linux/pid.h>
Serge E. Hallyn614b84c2009-04-06 19:01:08 -070034#include <linux/ipc_namespace.h>
Tejun Heo5a0e3ad2010-03-24 17:04:11 +090035#include <linux/slab.h>
Ingo Molnar5f921ae2006-03-26 01:37:17 -080036
Linus Torvalds1da177e2005-04-16 15:20:36 -070037#include <net/sock.h>
38#include "util.h"
39
40#define MQUEUE_MAGIC 0x19800202
41#define DIRENT_SIZE 20
42#define FILENT_SIZE 80
43
44#define SEND 0
45#define RECV 1
46
47#define STATE_NONE 0
48#define STATE_PENDING 1
49#define STATE_READY 2
50
Linus Torvalds1da177e2005-04-16 15:20:36 -070051struct ext_wait_queue { /* queue of sleeping tasks */
52 struct task_struct *task;
53 struct list_head list;
54 struct msg_msg *msg; /* ptr of loaded message */
55 int state; /* one of STATE_* values */
56};
57
58struct mqueue_inode_info {
59 spinlock_t lock;
60 struct inode vfs_inode;
61 wait_queue_head_t wait_q;
62
63 struct msg_msg **messages;
64 struct mq_attr attr;
65
66 struct sigevent notify;
Cedric Le Goatera03fcb72006-10-02 02:17:26 -070067 struct pid* notify_owner;
Adrian Bunk338cec32005-09-10 00:26:54 -070068 struct user_struct *user; /* user who created, for accounting */
Linus Torvalds1da177e2005-04-16 15:20:36 -070069 struct sock *notify_sock;
70 struct sk_buff *notify_cookie;
71
72 /* for tasks waiting for free space and messages, respectively */
73 struct ext_wait_queue e_wait_q[2];
74
75 unsigned long qsize; /* size of queue in memory (sum of all msgs) */
76};
77
Arjan van de Ven92e1d5b2007-02-12 00:55:39 -080078static const struct inode_operations mqueue_dir_inode_operations;
Arjan van de Ven9a321442007-02-12 00:55:35 -080079static const struct file_operations mqueue_file_operations;
Alexey Dobriyanb87221d2009-09-21 17:01:09 -070080static const struct super_operations mqueue_super_ops;
Linus Torvalds1da177e2005-04-16 15:20:36 -070081static void remove_notification(struct mqueue_inode_info *info);
82
Christoph Lametere18b8902006-12-06 20:33:20 -080083static struct kmem_cache *mqueue_inode_cachep;
Linus Torvalds1da177e2005-04-16 15:20:36 -070084
85static struct ctl_table_header * mq_sysctl_table;
86
87static inline struct mqueue_inode_info *MQUEUE_I(struct inode *inode)
88{
89 return container_of(inode, struct mqueue_inode_info, vfs_inode);
90}
91
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -070092/*
93 * This routine should be called with the mq_lock held.
94 */
95static inline struct ipc_namespace *__get_ns_from_inode(struct inode *inode)
Serge E. Hallyn614b84c2009-04-06 19:01:08 -070096{
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -070097 return get_ipc_ns(inode->i_sb->s_fs_info);
Serge E. Hallyn614b84c2009-04-06 19:01:08 -070098}
99
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700100static struct ipc_namespace *get_ns_from_inode(struct inode *inode)
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700101{
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700102 struct ipc_namespace *ns;
103
104 spin_lock(&mq_lock);
105 ns = __get_ns_from_inode(inode);
106 spin_unlock(&mq_lock);
107 return ns;
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700108}
109
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700110static struct inode *mqueue_get_inode(struct super_block *sb,
Al Viro1b9d5ff2011-07-24 14:18:20 -0400111 struct ipc_namespace *ipc_ns, umode_t mode,
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700112 struct mq_attr *attr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700113{
David Howells86a264a2008-11-14 10:39:18 +1100114 struct user_struct *u = current_user();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700115 struct inode *inode;
Jiri Slabyd40dcdb2011-07-26 16:08:47 -0700116 int ret = -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700117
118 inode = new_inode(sb);
Jiri Slaby04715202011-07-26 16:08:46 -0700119 if (!inode)
120 goto err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700121
Jiri Slaby04715202011-07-26 16:08:46 -0700122 inode->i_ino = get_next_ino();
123 inode->i_mode = mode;
124 inode->i_uid = current_fsuid();
125 inode->i_gid = current_fsgid();
126 inode->i_mtime = inode->i_ctime = inode->i_atime = CURRENT_TIME;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700127
Jiri Slaby04715202011-07-26 16:08:46 -0700128 if (S_ISREG(mode)) {
129 struct mqueue_inode_info *info;
130 struct task_struct *p = current;
131 unsigned long mq_bytes, mq_msg_tblsz;
André Goddard Rosac8308b12010-02-23 04:04:23 -0300132
Jiri Slaby04715202011-07-26 16:08:46 -0700133 inode->i_fop = &mqueue_file_operations;
134 inode->i_size = FILENT_SIZE;
135 /* mqueue specific info */
136 info = MQUEUE_I(inode);
137 spin_lock_init(&info->lock);
138 init_waitqueue_head(&info->wait_q);
139 INIT_LIST_HEAD(&info->e_wait_q[0].list);
140 INIT_LIST_HEAD(&info->e_wait_q[1].list);
141 info->notify_owner = NULL;
142 info->qsize = 0;
143 info->user = NULL; /* set when all is ok */
144 memset(&info->attr, 0, sizeof(info->attr));
145 info->attr.mq_maxmsg = ipc_ns->mq_msg_max;
146 info->attr.mq_msgsize = ipc_ns->mq_msgsize_max;
147 if (attr) {
148 info->attr.mq_maxmsg = attr->mq_maxmsg;
149 info->attr.mq_msgsize = attr->mq_msgsize;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700150 }
Jiri Slaby04715202011-07-26 16:08:46 -0700151 mq_msg_tblsz = info->attr.mq_maxmsg * sizeof(struct msg_msg *);
152 info->messages = kmalloc(mq_msg_tblsz, GFP_KERNEL);
153 if (!info->messages)
154 goto out_inode;
155
156 mq_bytes = (mq_msg_tblsz +
157 (info->attr.mq_maxmsg * info->attr.mq_msgsize));
158
159 spin_lock(&mq_lock);
160 if (u->mq_bytes + mq_bytes < u->mq_bytes ||
161 u->mq_bytes + mq_bytes > task_rlimit(p, RLIMIT_MSGQUEUE)) {
162 spin_unlock(&mq_lock);
163 /* mqueue_evict_inode() releases info->messages */
Jiri Slabyd40dcdb2011-07-26 16:08:47 -0700164 ret = -EMFILE;
Jiri Slaby04715202011-07-26 16:08:46 -0700165 goto out_inode;
166 }
167 u->mq_bytes += mq_bytes;
168 spin_unlock(&mq_lock);
169
170 /* all is ok */
171 info->user = get_uid(u);
172 } else if (S_ISDIR(mode)) {
173 inc_nlink(inode);
174 /* Some things misbehave if size == 0 on a directory */
175 inode->i_size = 2 * DIRENT_SIZE;
176 inode->i_op = &mqueue_dir_inode_operations;
177 inode->i_fop = &simple_dir_operations;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700178 }
Jiri Slaby04715202011-07-26 16:08:46 -0700179
Linus Torvalds1da177e2005-04-16 15:20:36 -0700180 return inode;
181out_inode:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700182 iput(inode);
Jiri Slaby04715202011-07-26 16:08:46 -0700183err:
Jiri Slabyd40dcdb2011-07-26 16:08:47 -0700184 return ERR_PTR(ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700185}
186
187static int mqueue_fill_super(struct super_block *sb, void *data, int silent)
188{
189 struct inode *inode;
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700190 struct ipc_namespace *ns = data;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300191 int error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700192
193 sb->s_blocksize = PAGE_CACHE_SIZE;
194 sb->s_blocksize_bits = PAGE_CACHE_SHIFT;
195 sb->s_magic = MQUEUE_MAGIC;
196 sb->s_op = &mqueue_super_ops;
197
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700198 inode = mqueue_get_inode(sb, ns, S_IFDIR | S_ISVTX | S_IRWXUGO,
199 NULL);
Jiri Slabyd40dcdb2011-07-26 16:08:47 -0700200 if (IS_ERR(inode)) {
201 error = PTR_ERR(inode);
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700202 goto out;
203 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700204
205 sb->s_root = d_alloc_root(inode);
206 if (!sb->s_root) {
207 iput(inode);
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700208 error = -ENOMEM;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300209 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700210 }
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300211 error = 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700212
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700213out:
214 return error;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700215}
216
Al Viroceefda62010-07-26 13:16:50 +0400217static struct dentry *mqueue_mount(struct file_system_type *fs_type,
David Howells454e2392006-06-23 02:02:57 -0700218 int flags, const char *dev_name,
Al Viroceefda62010-07-26 13:16:50 +0400219 void *data)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700220{
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700221 if (!(flags & MS_KERNMOUNT))
222 data = current->nsproxy->ipc_ns;
Al Viroceefda62010-07-26 13:16:50 +0400223 return mount_ns(fs_type, flags, data, mqueue_fill_super);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700224}
225
Alexey Dobriyan51cc5062008-07-25 19:45:34 -0700226static void init_once(void *foo)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700227{
228 struct mqueue_inode_info *p = (struct mqueue_inode_info *) foo;
229
Christoph Lametera35afb82007-05-16 22:10:57 -0700230 inode_init_once(&p->vfs_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700231}
232
233static struct inode *mqueue_alloc_inode(struct super_block *sb)
234{
235 struct mqueue_inode_info *ei;
236
Christoph Lametere94b1762006-12-06 20:33:17 -0800237 ei = kmem_cache_alloc(mqueue_inode_cachep, GFP_KERNEL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700238 if (!ei)
239 return NULL;
240 return &ei->vfs_inode;
241}
242
Nick Pigginfa0d7e32011-01-07 17:49:49 +1100243static void mqueue_i_callback(struct rcu_head *head)
244{
245 struct inode *inode = container_of(head, struct inode, i_rcu);
Nick Pigginfa0d7e32011-01-07 17:49:49 +1100246 kmem_cache_free(mqueue_inode_cachep, MQUEUE_I(inode));
247}
248
Linus Torvalds1da177e2005-04-16 15:20:36 -0700249static void mqueue_destroy_inode(struct inode *inode)
250{
Nick Pigginfa0d7e32011-01-07 17:49:49 +1100251 call_rcu(&inode->i_rcu, mqueue_i_callback);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700252}
253
Al Viro6d8af642010-06-05 16:29:45 -0400254static void mqueue_evict_inode(struct inode *inode)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700255{
256 struct mqueue_inode_info *info;
257 struct user_struct *user;
258 unsigned long mq_bytes;
259 int i;
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700260 struct ipc_namespace *ipc_ns;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700261
Al Viro6d8af642010-06-05 16:29:45 -0400262 end_writeback(inode);
263
264 if (S_ISDIR(inode->i_mode))
Linus Torvalds1da177e2005-04-16 15:20:36 -0700265 return;
Al Viro6d8af642010-06-05 16:29:45 -0400266
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700267 ipc_ns = get_ns_from_inode(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700268 info = MQUEUE_I(inode);
269 spin_lock(&info->lock);
270 for (i = 0; i < info->attr.mq_curmsgs; i++)
271 free_msg(info->messages[i]);
272 kfree(info->messages);
273 spin_unlock(&info->lock);
274
André Goddard Rosa8834cf72010-02-23 04:04:24 -0300275 /* Total amount of bytes accounted for the mqueue */
276 mq_bytes = info->attr.mq_maxmsg * (sizeof(struct msg_msg *)
277 + info->attr.mq_msgsize);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700278 user = info->user;
279 if (user) {
280 spin_lock(&mq_lock);
281 user->mq_bytes -= mq_bytes;
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700282 /*
283 * get_ns_from_inode() ensures that the
284 * (ipc_ns = sb->s_fs_info) is either a valid ipc_ns
285 * to which we now hold a reference, or it is NULL.
286 * We can't put it here under mq_lock, though.
287 */
288 if (ipc_ns)
289 ipc_ns->mq_queues_count--;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700290 spin_unlock(&mq_lock);
291 free_uid(user);
292 }
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700293 if (ipc_ns)
294 put_ipc_ns(ipc_ns);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700295}
296
297static int mqueue_create(struct inode *dir, struct dentry *dentry,
Al Viro4acdaf22011-07-26 01:42:34 -0400298 umode_t mode, struct nameidata *nd)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700299{
300 struct inode *inode;
301 struct mq_attr *attr = dentry->d_fsdata;
302 int error;
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700303 struct ipc_namespace *ipc_ns;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700304
305 spin_lock(&mq_lock);
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700306 ipc_ns = __get_ns_from_inode(dir);
307 if (!ipc_ns) {
308 error = -EACCES;
309 goto out_unlock;
310 }
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700311 if (ipc_ns->mq_queues_count >= ipc_ns->mq_queues_max &&
312 !capable(CAP_SYS_RESOURCE)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -0700313 error = -ENOSPC;
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700314 goto out_unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700315 }
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700316 ipc_ns->mq_queues_count++;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700317 spin_unlock(&mq_lock);
318
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700319 inode = mqueue_get_inode(dir->i_sb, ipc_ns, mode, attr);
Jiri Slabyd40dcdb2011-07-26 16:08:47 -0700320 if (IS_ERR(inode)) {
321 error = PTR_ERR(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700322 spin_lock(&mq_lock);
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700323 ipc_ns->mq_queues_count--;
324 goto out_unlock;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700325 }
326
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700327 put_ipc_ns(ipc_ns);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700328 dir->i_size += DIRENT_SIZE;
329 dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME;
330
331 d_instantiate(dentry, inode);
332 dget(dentry);
333 return 0;
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700334out_unlock:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700335 spin_unlock(&mq_lock);
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700336 if (ipc_ns)
337 put_ipc_ns(ipc_ns);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700338 return error;
339}
340
341static int mqueue_unlink(struct inode *dir, struct dentry *dentry)
342{
343 struct inode *inode = dentry->d_inode;
344
345 dir->i_ctime = dir->i_mtime = dir->i_atime = CURRENT_TIME;
346 dir->i_size -= DIRENT_SIZE;
Dave Hansen9a53c3a2006-09-30 23:29:03 -0700347 drop_nlink(inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700348 dput(dentry);
349 return 0;
350}
351
352/*
353* This is routine for system read from queue file.
354* To avoid mess with doing here some sort of mq_receive we allow
355* to read only queue size & notification info (the only values
356* that are interesting from user point of view and aren't accessible
357* through std routines)
358*/
359static ssize_t mqueue_read_file(struct file *filp, char __user *u_data,
Akinobu Mitaf1a43f92008-07-25 01:48:07 -0700360 size_t count, loff_t *off)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700361{
Josef Sipek6d630792006-12-08 02:37:11 -0800362 struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700363 char buffer[FILENT_SIZE];
Akinobu Mitaf1a43f92008-07-25 01:48:07 -0700364 ssize_t ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700365
366 spin_lock(&info->lock);
367 snprintf(buffer, sizeof(buffer),
368 "QSIZE:%-10lu NOTIFY:%-5d SIGNO:%-5d NOTIFY_PID:%-6d\n",
369 info->qsize,
370 info->notify_owner ? info->notify.sigev_notify : 0,
371 (info->notify_owner &&
372 info->notify.sigev_notify == SIGEV_SIGNAL) ?
373 info->notify.sigev_signo : 0,
Pavel Emelyanov6c5f3e72008-02-08 04:19:20 -0800374 pid_vnr(info->notify_owner));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700375 spin_unlock(&info->lock);
376 buffer[sizeof(buffer)-1] = '\0';
Linus Torvalds1da177e2005-04-16 15:20:36 -0700377
Akinobu Mitaf1a43f92008-07-25 01:48:07 -0700378 ret = simple_read_from_buffer(u_data, count, off, buffer,
379 strlen(buffer));
380 if (ret <= 0)
381 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700382
Josef Sipek6d630792006-12-08 02:37:11 -0800383 filp->f_path.dentry->d_inode->i_atime = filp->f_path.dentry->d_inode->i_ctime = CURRENT_TIME;
Akinobu Mitaf1a43f92008-07-25 01:48:07 -0700384 return ret;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700385}
386
Miklos Szeredi75e1fcc2006-06-23 02:05:12 -0700387static int mqueue_flush_file(struct file *filp, fl_owner_t id)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700388{
Josef Sipek6d630792006-12-08 02:37:11 -0800389 struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700390
391 spin_lock(&info->lock);
Cedric Le Goatera03fcb72006-10-02 02:17:26 -0700392 if (task_tgid(current) == info->notify_owner)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700393 remove_notification(info);
394
395 spin_unlock(&info->lock);
396 return 0;
397}
398
399static unsigned int mqueue_poll_file(struct file *filp, struct poll_table_struct *poll_tab)
400{
Josef Sipek6d630792006-12-08 02:37:11 -0800401 struct mqueue_inode_info *info = MQUEUE_I(filp->f_path.dentry->d_inode);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700402 int retval = 0;
403
404 poll_wait(filp, &info->wait_q, poll_tab);
405
406 spin_lock(&info->lock);
407 if (info->attr.mq_curmsgs)
408 retval = POLLIN | POLLRDNORM;
409
410 if (info->attr.mq_curmsgs < info->attr.mq_maxmsg)
411 retval |= POLLOUT | POLLWRNORM;
412 spin_unlock(&info->lock);
413
414 return retval;
415}
416
417/* Adds current to info->e_wait_q[sr] before element with smaller prio */
418static void wq_add(struct mqueue_inode_info *info, int sr,
419 struct ext_wait_queue *ewp)
420{
421 struct ext_wait_queue *walk;
422
423 ewp->task = current;
424
425 list_for_each_entry(walk, &info->e_wait_q[sr].list, list) {
426 if (walk->task->static_prio <= current->static_prio) {
427 list_add_tail(&ewp->list, &walk->list);
428 return;
429 }
430 }
431 list_add_tail(&ewp->list, &info->e_wait_q[sr].list);
432}
433
434/*
435 * Puts current task to sleep. Caller must hold queue lock. After return
436 * lock isn't held.
437 * sr: SEND or RECV
438 */
439static int wq_sleep(struct mqueue_inode_info *info, int sr,
Carsten Emde9ca7d8e2010-04-02 22:40:20 +0200440 ktime_t *timeout, struct ext_wait_queue *ewp)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700441{
442 int retval;
443 signed long time;
444
445 wq_add(info, sr, ewp);
446
447 for (;;) {
448 set_current_state(TASK_INTERRUPTIBLE);
449
450 spin_unlock(&info->lock);
Wanlong Gao32ea8452011-10-31 17:06:35 -0700451 time = schedule_hrtimeout_range_clock(timeout, 0,
452 HRTIMER_MODE_ABS, CLOCK_REALTIME);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700453
454 while (ewp->state == STATE_PENDING)
455 cpu_relax();
456
457 if (ewp->state == STATE_READY) {
458 retval = 0;
459 goto out;
460 }
461 spin_lock(&info->lock);
462 if (ewp->state == STATE_READY) {
463 retval = 0;
464 goto out_unlock;
465 }
466 if (signal_pending(current)) {
467 retval = -ERESTARTSYS;
468 break;
469 }
470 if (time == 0) {
471 retval = -ETIMEDOUT;
472 break;
473 }
474 }
475 list_del(&ewp->list);
476out_unlock:
477 spin_unlock(&info->lock);
478out:
479 return retval;
480}
481
482/*
483 * Returns waiting task that should be serviced first or NULL if none exists
484 */
485static struct ext_wait_queue *wq_get_first_waiter(
486 struct mqueue_inode_info *info, int sr)
487{
488 struct list_head *ptr;
489
490 ptr = info->e_wait_q[sr].list.prev;
491 if (ptr == &info->e_wait_q[sr].list)
492 return NULL;
493 return list_entry(ptr, struct ext_wait_queue, list);
494}
495
496/* Auxiliary functions to manipulate messages' list */
497static void msg_insert(struct msg_msg *ptr, struct mqueue_inode_info *info)
498{
499 int k;
500
501 k = info->attr.mq_curmsgs - 1;
502 while (k >= 0 && info->messages[k]->m_type >= ptr->m_type) {
503 info->messages[k + 1] = info->messages[k];
504 k--;
505 }
506 info->attr.mq_curmsgs++;
507 info->qsize += ptr->m_ts;
508 info->messages[k + 1] = ptr;
509}
510
511static inline struct msg_msg *msg_get(struct mqueue_inode_info *info)
512{
513 info->qsize -= info->messages[--info->attr.mq_curmsgs]->m_ts;
514 return info->messages[info->attr.mq_curmsgs];
515}
516
517static inline void set_cookie(struct sk_buff *skb, char code)
518{
519 ((char*)skb->data)[NOTIFY_COOKIE_LEN-1] = code;
520}
521
522/*
523 * The next function is only to split too long sys_mq_timedsend
524 */
525static void __do_notify(struct mqueue_inode_info *info)
526{
527 /* notification
528 * invoked when there is registered process and there isn't process
529 * waiting synchronously for message AND state of queue changed from
530 * empty to not empty. Here we are sure that no one is waiting
531 * synchronously. */
532 if (info->notify_owner &&
533 info->attr.mq_curmsgs == 1) {
534 struct siginfo sig_i;
535 switch (info->notify.sigev_notify) {
536 case SIGEV_NONE:
537 break;
538 case SIGEV_SIGNAL:
539 /* sends signal */
540
541 sig_i.si_signo = info->notify.sigev_signo;
542 sig_i.si_errno = 0;
543 sig_i.si_code = SI_MESGQ;
544 sig_i.si_value = info->notify.sigev_value;
Sukadev Bhattiprolua6684992009-01-07 18:08:50 -0800545 sig_i.si_pid = task_tgid_nr_ns(current,
546 ns_of_pid(info->notify_owner));
David Howells414c0702008-11-14 10:39:06 +1100547 sig_i.si_uid = current_uid();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700548
Cedric Le Goatera03fcb72006-10-02 02:17:26 -0700549 kill_pid_info(info->notify.sigev_signo,
550 &sig_i, info->notify_owner);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700551 break;
552 case SIGEV_THREAD:
553 set_cookie(info->notify_cookie, NOTIFY_WOKENUP);
Denis V. Lunev7ee015e2007-10-10 21:14:03 -0700554 netlink_sendskb(info->notify_sock, info->notify_cookie);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700555 break;
556 }
557 /* after notification unregisters process */
Cedric Le Goatera03fcb72006-10-02 02:17:26 -0700558 put_pid(info->notify_owner);
559 info->notify_owner = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700560 }
561 wake_up(&info->wait_q);
562}
563
Carsten Emde9ca7d8e2010-04-02 22:40:20 +0200564static int prepare_timeout(const struct timespec __user *u_abs_timeout,
565 ktime_t *expires, struct timespec *ts)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700566{
Carsten Emde9ca7d8e2010-04-02 22:40:20 +0200567 if (copy_from_user(ts, u_abs_timeout, sizeof(struct timespec)))
568 return -EFAULT;
569 if (!timespec_valid(ts))
570 return -EINVAL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700571
Carsten Emde9ca7d8e2010-04-02 22:40:20 +0200572 *expires = timespec_to_ktime(*ts);
573 return 0;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700574}
575
576static void remove_notification(struct mqueue_inode_info *info)
577{
Cedric Le Goatera03fcb72006-10-02 02:17:26 -0700578 if (info->notify_owner != NULL &&
Linus Torvalds1da177e2005-04-16 15:20:36 -0700579 info->notify.sigev_notify == SIGEV_THREAD) {
580 set_cookie(info->notify_cookie, NOTIFY_REMOVED);
Denis V. Lunev7ee015e2007-10-10 21:14:03 -0700581 netlink_sendskb(info->notify_sock, info->notify_cookie);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700582 }
Cedric Le Goatera03fcb72006-10-02 02:17:26 -0700583 put_pid(info->notify_owner);
584 info->notify_owner = NULL;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700585}
586
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700587static int mq_attr_ok(struct ipc_namespace *ipc_ns, struct mq_attr *attr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700588{
589 if (attr->mq_maxmsg <= 0 || attr->mq_msgsize <= 0)
590 return 0;
591 if (capable(CAP_SYS_RESOURCE)) {
592 if (attr->mq_maxmsg > HARD_MSGMAX)
593 return 0;
594 } else {
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700595 if (attr->mq_maxmsg > ipc_ns->mq_msg_max ||
596 attr->mq_msgsize > ipc_ns->mq_msgsize_max)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700597 return 0;
598 }
599 /* check for overflow */
600 if (attr->mq_msgsize > ULONG_MAX/attr->mq_maxmsg)
601 return 0;
André Goddard Rosa8834cf72010-02-23 04:04:24 -0300602 if ((unsigned long)(attr->mq_maxmsg * (attr->mq_msgsize
603 + sizeof (struct msg_msg *))) <
Linus Torvalds1da177e2005-04-16 15:20:36 -0700604 (unsigned long)(attr->mq_maxmsg * attr->mq_msgsize))
605 return 0;
606 return 1;
607}
608
609/*
610 * Invoked when creating a new queue via sys_mq_open
611 */
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700612static struct file *do_create(struct ipc_namespace *ipc_ns, struct dentry *dir,
Al Viro4acdaf22011-07-26 01:42:34 -0400613 struct dentry *dentry, int oflag, umode_t mode,
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700614 struct mq_attr *attr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700615{
David Howells745ca242008-11-14 10:39:22 +1100616 const struct cred *cred = current_cred();
Dave Hansen4a3fd212008-02-15 14:37:48 -0800617 struct file *result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700618 int ret;
619
Al Viro564f6992008-12-14 04:02:26 -0500620 if (attr) {
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300621 if (!mq_attr_ok(ipc_ns, attr)) {
622 ret = -EINVAL;
Alexander Viro7c7dce92006-01-14 15:29:55 -0500623 goto out;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300624 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700625 /* store for use during create */
Al Viro564f6992008-12-14 04:02:26 -0500626 dentry->d_fsdata = attr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700627 }
628
Al Viroce3b0f82009-03-29 19:08:22 -0400629 mode &= ~current_umask();
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700630 ret = mnt_want_write(ipc_ns->mq_mnt);
Dave Hansen4a3fd212008-02-15 14:37:48 -0800631 if (ret)
632 goto out;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700633 ret = vfs_create(dir->d_inode, dentry, mode, NULL);
634 dentry->d_fsdata = NULL;
635 if (ret)
Dave Hansen4a3fd212008-02-15 14:37:48 -0800636 goto out_drop_write;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700637
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700638 result = dentry_open(dentry, ipc_ns->mq_mnt, oflag, cred);
Dave Hansen4a3fd212008-02-15 14:37:48 -0800639 /*
640 * dentry_open() took a persistent mnt_want_write(),
641 * so we can now drop this one.
642 */
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700643 mnt_drop_write(ipc_ns->mq_mnt);
Dave Hansen4a3fd212008-02-15 14:37:48 -0800644 return result;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700645
Dave Hansen4a3fd212008-02-15 14:37:48 -0800646out_drop_write:
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700647 mnt_drop_write(ipc_ns->mq_mnt);
Alexander Viro7c7dce92006-01-14 15:29:55 -0500648out:
649 dput(dentry);
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700650 mntput(ipc_ns->mq_mnt);
Alexander Viro7c7dce92006-01-14 15:29:55 -0500651 return ERR_PTR(ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700652}
653
654/* Opens existing queue */
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700655static struct file *do_open(struct ipc_namespace *ipc_ns,
656 struct dentry *dentry, int oflag)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700657{
André Goddard Rosa04db0dd2010-02-23 04:04:25 -0300658 int ret;
David Howells745ca242008-11-14 10:39:22 +1100659 const struct cred *cred = current_cred();
660
661 static const int oflag2acc[O_ACCMODE] = { MAY_READ, MAY_WRITE,
662 MAY_READ | MAY_WRITE };
Linus Torvalds1da177e2005-04-16 15:20:36 -0700663
Alexander Viro7c7dce92006-01-14 15:29:55 -0500664 if ((oflag & O_ACCMODE) == (O_RDWR | O_WRONLY)) {
André Goddard Rosa04db0dd2010-02-23 04:04:25 -0300665 ret = -EINVAL;
666 goto err;
Alexander Viro7c7dce92006-01-14 15:29:55 -0500667 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700668
Al Virof419a2e2008-07-22 00:07:17 -0400669 if (inode_permission(dentry->d_inode, oflag2acc[oflag & O_ACCMODE])) {
André Goddard Rosa04db0dd2010-02-23 04:04:25 -0300670 ret = -EACCES;
671 goto err;
Alexander Viro7c7dce92006-01-14 15:29:55 -0500672 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700673
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700674 return dentry_open(dentry, ipc_ns->mq_mnt, oflag, cred);
André Goddard Rosa04db0dd2010-02-23 04:04:25 -0300675
676err:
677 dput(dentry);
678 mntput(ipc_ns->mq_mnt);
679 return ERR_PTR(ret);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700680}
681
Al Virodf0a4282011-07-26 05:26:10 -0400682SYSCALL_DEFINE4(mq_open, const char __user *, u_name, int, oflag, umode_t, mode,
Heiko Carstensd5460c92009-01-14 14:14:27 +0100683 struct mq_attr __user *, u_attr)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700684{
685 struct dentry *dentry;
686 struct file *filp;
687 char *name;
Al Viro564f6992008-12-14 04:02:26 -0500688 struct mq_attr attr;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700689 int fd, error;
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700690 struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700691
Al Viro564f6992008-12-14 04:02:26 -0500692 if (u_attr && copy_from_user(&attr, u_attr, sizeof(struct mq_attr)))
693 return -EFAULT;
694
695 audit_mq_open(oflag, mode, u_attr ? &attr : NULL);
George C. Wilson20ca73b2006-05-24 16:09:55 -0500696
Linus Torvalds1da177e2005-04-16 15:20:36 -0700697 if (IS_ERR(name = getname(u_name)))
698 return PTR_ERR(name);
699
Ulrich Drepper269f2132008-05-03 15:28:45 -0400700 fd = get_unused_fd_flags(O_CLOEXEC);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700701 if (fd < 0)
702 goto out_putname;
703
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700704 mutex_lock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex);
705 dentry = lookup_one_len(name, ipc_ns->mq_mnt->mnt_root, strlen(name));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700706 if (IS_ERR(dentry)) {
707 error = PTR_ERR(dentry);
André Goddard Rosa4294a8e2010-02-23 04:04:28 -0300708 goto out_putfd;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700709 }
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700710 mntget(ipc_ns->mq_mnt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700711
712 if (oflag & O_CREAT) {
713 if (dentry->d_inode) { /* entry already exists */
Al Viro5a190ae2007-06-07 12:19:32 -0400714 audit_inode(name, dentry);
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300715 if (oflag & O_EXCL) {
716 error = -EEXIST;
Alexander Viro7c7dce92006-01-14 15:29:55 -0500717 goto out;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300718 }
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700719 filp = do_open(ipc_ns, dentry, oflag);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700720 } else {
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700721 filp = do_create(ipc_ns, ipc_ns->mq_mnt->mnt_root,
722 dentry, oflag, mode,
Al Viro564f6992008-12-14 04:02:26 -0500723 u_attr ? &attr : NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700724 }
Alexander Viro7c7dce92006-01-14 15:29:55 -0500725 } else {
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300726 if (!dentry->d_inode) {
727 error = -ENOENT;
Alexander Viro7c7dce92006-01-14 15:29:55 -0500728 goto out;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300729 }
Al Viro5a190ae2007-06-07 12:19:32 -0400730 audit_inode(name, dentry);
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700731 filp = do_open(ipc_ns, dentry, oflag);
Alexander Viro7c7dce92006-01-14 15:29:55 -0500732 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700733
734 if (IS_ERR(filp)) {
735 error = PTR_ERR(filp);
736 goto out_putfd;
737 }
738
Linus Torvalds1da177e2005-04-16 15:20:36 -0700739 fd_install(fd, filp);
740 goto out_upsem;
741
Alexander Viro7c7dce92006-01-14 15:29:55 -0500742out:
743 dput(dentry);
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700744 mntput(ipc_ns->mq_mnt);
Alexander Viro7c7dce92006-01-14 15:29:55 -0500745out_putfd:
Linus Torvalds1da177e2005-04-16 15:20:36 -0700746 put_unused_fd(fd);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700747 fd = error;
748out_upsem:
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700749 mutex_unlock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700750out_putname:
751 putname(name);
752 return fd;
753}
754
Heiko Carstensd5460c92009-01-14 14:14:27 +0100755SYSCALL_DEFINE1(mq_unlink, const char __user *, u_name)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700756{
757 int err;
758 char *name;
759 struct dentry *dentry;
760 struct inode *inode = NULL;
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -0700761 struct ipc_namespace *ipc_ns = current->nsproxy->ipc_ns;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700762
763 name = getname(u_name);
764 if (IS_ERR(name))
765 return PTR_ERR(name);
766
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700767 mutex_lock_nested(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex,
Peter Zijlstra7a434812007-03-06 01:42:09 -0800768 I_MUTEX_PARENT);
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700769 dentry = lookup_one_len(name, ipc_ns->mq_mnt->mnt_root, strlen(name));
Linus Torvalds1da177e2005-04-16 15:20:36 -0700770 if (IS_ERR(dentry)) {
771 err = PTR_ERR(dentry);
772 goto out_unlock;
773 }
774
775 if (!dentry->d_inode) {
776 err = -ENOENT;
777 goto out_err;
778 }
779
780 inode = dentry->d_inode;
781 if (inode)
Al Viro7de9c6e2010-10-23 11:11:40 -0400782 ihold(inode);
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700783 err = mnt_want_write(ipc_ns->mq_mnt);
Dave Hansen06227532008-02-15 14:37:34 -0800784 if (err)
785 goto out_err;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700786 err = vfs_unlink(dentry->d_parent->d_inode, dentry);
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700787 mnt_drop_write(ipc_ns->mq_mnt);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700788out_err:
789 dput(dentry);
790
791out_unlock:
Serge E. Hallyn614b84c2009-04-06 19:01:08 -0700792 mutex_unlock(&ipc_ns->mq_mnt->mnt_root->d_inode->i_mutex);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700793 putname(name);
794 if (inode)
795 iput(inode);
796
797 return err;
798}
799
800/* Pipelined send and receive functions.
801 *
802 * If a receiver finds no waiting message, then it registers itself in the
803 * list of waiting receivers. A sender checks that list before adding the new
804 * message into the message array. If there is a waiting receiver, then it
805 * bypasses the message array and directly hands the message over to the
806 * receiver.
807 * The receiver accepts the message and returns without grabbing the queue
808 * spinlock. Therefore an intermediate STATE_PENDING state and memory barriers
809 * are necessary. The same algorithm is used for sysv semaphores, see
Serge E. Hallyn7b7a3172006-03-28 01:56:23 -0800810 * ipc/sem.c for more details.
Linus Torvalds1da177e2005-04-16 15:20:36 -0700811 *
812 * The same algorithm is used for senders.
813 */
814
815/* pipelined_send() - send a message directly to the task waiting in
816 * sys_mq_timedreceive() (without inserting message into a queue).
817 */
818static inline void pipelined_send(struct mqueue_inode_info *info,
819 struct msg_msg *message,
820 struct ext_wait_queue *receiver)
821{
822 receiver->msg = message;
823 list_del(&receiver->list);
824 receiver->state = STATE_PENDING;
825 wake_up_process(receiver->task);
akpm@osdl.orgd59dd462005-05-01 08:58:47 -0700826 smp_wmb();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700827 receiver->state = STATE_READY;
828}
829
830/* pipelined_receive() - if there is task waiting in sys_mq_timedsend()
831 * gets its message and put to the queue (we have one free place for sure). */
832static inline void pipelined_receive(struct mqueue_inode_info *info)
833{
834 struct ext_wait_queue *sender = wq_get_first_waiter(info, SEND);
835
836 if (!sender) {
837 /* for poll */
838 wake_up_interruptible(&info->wait_q);
839 return;
840 }
841 msg_insert(sender->msg, info);
842 list_del(&sender->list);
843 sender->state = STATE_PENDING;
844 wake_up_process(sender->task);
akpm@osdl.orgd59dd462005-05-01 08:58:47 -0700845 smp_wmb();
Linus Torvalds1da177e2005-04-16 15:20:36 -0700846 sender->state = STATE_READY;
847}
848
Heiko Carstensc4ea37c2009-01-14 14:14:28 +0100849SYSCALL_DEFINE5(mq_timedsend, mqd_t, mqdes, const char __user *, u_msg_ptr,
850 size_t, msg_len, unsigned int, msg_prio,
851 const struct timespec __user *, u_abs_timeout)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700852{
853 struct file *filp;
854 struct inode *inode;
855 struct ext_wait_queue wait;
856 struct ext_wait_queue *receiver;
857 struct msg_msg *msg_ptr;
858 struct mqueue_inode_info *info;
Carsten Emde9ca7d8e2010-04-02 22:40:20 +0200859 ktime_t expires, *timeout = NULL;
860 struct timespec ts;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700861 int ret;
862
Al Viroc32c8af2008-12-14 03:46:48 -0500863 if (u_abs_timeout) {
Carsten Emde9ca7d8e2010-04-02 22:40:20 +0200864 int res = prepare_timeout(u_abs_timeout, &expires, &ts);
865 if (res)
866 return res;
867 timeout = &expires;
Al Viroc32c8af2008-12-14 03:46:48 -0500868 }
George C. Wilson20ca73b2006-05-24 16:09:55 -0500869
Linus Torvalds1da177e2005-04-16 15:20:36 -0700870 if (unlikely(msg_prio >= (unsigned long) MQ_PRIO_MAX))
871 return -EINVAL;
872
Carsten Emde9ca7d8e2010-04-02 22:40:20 +0200873 audit_mq_sendrecv(mqdes, msg_len, msg_prio, timeout ? &ts : NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700874
Linus Torvalds1da177e2005-04-16 15:20:36 -0700875 filp = fget(mqdes);
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300876 if (unlikely(!filp)) {
877 ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700878 goto out;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300879 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700880
Josef Sipek6d630792006-12-08 02:37:11 -0800881 inode = filp->f_path.dentry->d_inode;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300882 if (unlikely(filp->f_op != &mqueue_file_operations)) {
883 ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700884 goto out_fput;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300885 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700886 info = MQUEUE_I(inode);
Al Viro5a190ae2007-06-07 12:19:32 -0400887 audit_inode(NULL, filp->f_path.dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700888
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300889 if (unlikely(!(filp->f_mode & FMODE_WRITE))) {
890 ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700891 goto out_fput;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300892 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700893
894 if (unlikely(msg_len > info->attr.mq_msgsize)) {
895 ret = -EMSGSIZE;
896 goto out_fput;
897 }
898
899 /* First try to allocate memory, before doing anything with
900 * existing queues. */
901 msg_ptr = load_msg(u_msg_ptr, msg_len);
902 if (IS_ERR(msg_ptr)) {
903 ret = PTR_ERR(msg_ptr);
904 goto out_fput;
905 }
906 msg_ptr->m_ts = msg_len;
907 msg_ptr->m_type = msg_prio;
908
909 spin_lock(&info->lock);
910
911 if (info->attr.mq_curmsgs == info->attr.mq_maxmsg) {
912 if (filp->f_flags & O_NONBLOCK) {
913 spin_unlock(&info->lock);
914 ret = -EAGAIN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700915 } else {
916 wait.task = current;
917 wait.msg = (void *) msg_ptr;
918 wait.state = STATE_NONE;
919 ret = wq_sleep(info, SEND, timeout, &wait);
920 }
921 if (ret < 0)
922 free_msg(msg_ptr);
923 } else {
924 receiver = wq_get_first_waiter(info, RECV);
925 if (receiver) {
926 pipelined_send(info, msg_ptr, receiver);
927 } else {
928 /* adds message to the queue */
929 msg_insert(msg_ptr, info);
930 __do_notify(info);
931 }
932 inode->i_atime = inode->i_mtime = inode->i_ctime =
933 CURRENT_TIME;
934 spin_unlock(&info->lock);
935 ret = 0;
936 }
937out_fput:
938 fput(filp);
939out:
940 return ret;
941}
942
Heiko Carstensc4ea37c2009-01-14 14:14:28 +0100943SYSCALL_DEFINE5(mq_timedreceive, mqd_t, mqdes, char __user *, u_msg_ptr,
944 size_t, msg_len, unsigned int __user *, u_msg_prio,
945 const struct timespec __user *, u_abs_timeout)
Linus Torvalds1da177e2005-04-16 15:20:36 -0700946{
Linus Torvalds1da177e2005-04-16 15:20:36 -0700947 ssize_t ret;
948 struct msg_msg *msg_ptr;
949 struct file *filp;
950 struct inode *inode;
951 struct mqueue_inode_info *info;
952 struct ext_wait_queue wait;
Carsten Emde9ca7d8e2010-04-02 22:40:20 +0200953 ktime_t expires, *timeout = NULL;
954 struct timespec ts;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700955
Al Viroc32c8af2008-12-14 03:46:48 -0500956 if (u_abs_timeout) {
Carsten Emde9ca7d8e2010-04-02 22:40:20 +0200957 int res = prepare_timeout(u_abs_timeout, &expires, &ts);
958 if (res)
959 return res;
960 timeout = &expires;
Al Viroc32c8af2008-12-14 03:46:48 -0500961 }
George C. Wilson20ca73b2006-05-24 16:09:55 -0500962
Carsten Emde9ca7d8e2010-04-02 22:40:20 +0200963 audit_mq_sendrecv(mqdes, msg_len, 0, timeout ? &ts : NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700964
Linus Torvalds1da177e2005-04-16 15:20:36 -0700965 filp = fget(mqdes);
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300966 if (unlikely(!filp)) {
967 ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700968 goto out;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300969 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700970
Josef Sipek6d630792006-12-08 02:37:11 -0800971 inode = filp->f_path.dentry->d_inode;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300972 if (unlikely(filp->f_op != &mqueue_file_operations)) {
973 ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700974 goto out_fput;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300975 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700976 info = MQUEUE_I(inode);
Al Viro5a190ae2007-06-07 12:19:32 -0400977 audit_inode(NULL, filp->f_path.dentry);
Linus Torvalds1da177e2005-04-16 15:20:36 -0700978
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300979 if (unlikely(!(filp->f_mode & FMODE_READ))) {
980 ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700981 goto out_fput;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -0300982 }
Linus Torvalds1da177e2005-04-16 15:20:36 -0700983
984 /* checks if buffer is big enough */
985 if (unlikely(msg_len < info->attr.mq_msgsize)) {
986 ret = -EMSGSIZE;
987 goto out_fput;
988 }
989
990 spin_lock(&info->lock);
991 if (info->attr.mq_curmsgs == 0) {
992 if (filp->f_flags & O_NONBLOCK) {
993 spin_unlock(&info->lock);
994 ret = -EAGAIN;
Linus Torvalds1da177e2005-04-16 15:20:36 -0700995 } else {
996 wait.task = current;
997 wait.state = STATE_NONE;
998 ret = wq_sleep(info, RECV, timeout, &wait);
999 msg_ptr = wait.msg;
1000 }
1001 } else {
1002 msg_ptr = msg_get(info);
1003
1004 inode->i_atime = inode->i_mtime = inode->i_ctime =
1005 CURRENT_TIME;
1006
1007 /* There is now free space in queue. */
1008 pipelined_receive(info);
1009 spin_unlock(&info->lock);
1010 ret = 0;
1011 }
1012 if (ret == 0) {
1013 ret = msg_ptr->m_ts;
1014
1015 if ((u_msg_prio && put_user(msg_ptr->m_type, u_msg_prio)) ||
1016 store_msg(u_msg_ptr, msg_ptr, msg_ptr->m_ts)) {
1017 ret = -EFAULT;
1018 }
1019 free_msg(msg_ptr);
1020 }
1021out_fput:
1022 fput(filp);
1023out:
1024 return ret;
1025}
1026
1027/*
1028 * Notes: the case when user wants us to deregister (with NULL as pointer)
1029 * and he isn't currently owner of notification, will be silently discarded.
1030 * It isn't explicitly defined in the POSIX.
1031 */
Heiko Carstensc4ea37c2009-01-14 14:14:28 +01001032SYSCALL_DEFINE2(mq_notify, mqd_t, mqdes,
1033 const struct sigevent __user *, u_notification)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001034{
1035 int ret;
1036 struct file *filp;
1037 struct sock *sock;
1038 struct inode *inode;
1039 struct sigevent notification;
1040 struct mqueue_inode_info *info;
1041 struct sk_buff *nc;
1042
Al Viro20114f72008-12-10 07:16:12 -05001043 if (u_notification) {
1044 if (copy_from_user(&notification, u_notification,
1045 sizeof(struct sigevent)))
1046 return -EFAULT;
1047 }
1048
1049 audit_mq_notify(mqdes, u_notification ? &notification : NULL);
George C. Wilson20ca73b2006-05-24 16:09:55 -05001050
Linus Torvalds1da177e2005-04-16 15:20:36 -07001051 nc = NULL;
1052 sock = NULL;
1053 if (u_notification != NULL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001054 if (unlikely(notification.sigev_notify != SIGEV_NONE &&
1055 notification.sigev_notify != SIGEV_SIGNAL &&
1056 notification.sigev_notify != SIGEV_THREAD))
1057 return -EINVAL;
1058 if (notification.sigev_notify == SIGEV_SIGNAL &&
Jesper Juhl7ed20e12005-05-01 08:59:14 -07001059 !valid_signal(notification.sigev_signo)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001060 return -EINVAL;
1061 }
1062 if (notification.sigev_notify == SIGEV_THREAD) {
Patrick McHardyc3d8d1e2007-11-07 02:42:09 -08001063 long timeo;
1064
Linus Torvalds1da177e2005-04-16 15:20:36 -07001065 /* create the notify skb */
1066 nc = alloc_skb(NOTIFY_COOKIE_LEN, GFP_KERNEL);
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001067 if (!nc) {
1068 ret = -ENOMEM;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001069 goto out;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001070 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001071 if (copy_from_user(nc->data,
1072 notification.sigev_value.sival_ptr,
1073 NOTIFY_COOKIE_LEN)) {
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001074 ret = -EFAULT;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001075 goto out;
1076 }
1077
1078 /* TODO: add a header? */
1079 skb_put(nc, NOTIFY_COOKIE_LEN);
1080 /* and attach it to the socket */
1081retry:
1082 filp = fget(notification.sigev_signo);
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001083 if (!filp) {
1084 ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001085 goto out;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001086 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001087 sock = netlink_getsockbyfilp(filp);
1088 fput(filp);
1089 if (IS_ERR(sock)) {
1090 ret = PTR_ERR(sock);
1091 sock = NULL;
1092 goto out;
1093 }
1094
Patrick McHardyc3d8d1e2007-11-07 02:42:09 -08001095 timeo = MAX_SCHEDULE_TIMEOUT;
Denis V. Lunev9457afe2008-06-05 11:23:39 -07001096 ret = netlink_attachskb(sock, nc, &timeo, NULL);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001097 if (ret == 1)
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001098 goto retry;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001099 if (ret) {
1100 sock = NULL;
1101 nc = NULL;
1102 goto out;
1103 }
1104 }
1105 }
1106
Linus Torvalds1da177e2005-04-16 15:20:36 -07001107 filp = fget(mqdes);
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001108 if (!filp) {
1109 ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001110 goto out;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001111 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001112
Josef Sipek6d630792006-12-08 02:37:11 -08001113 inode = filp->f_path.dentry->d_inode;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001114 if (unlikely(filp->f_op != &mqueue_file_operations)) {
1115 ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001116 goto out_fput;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001117 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001118 info = MQUEUE_I(inode);
1119
1120 ret = 0;
1121 spin_lock(&info->lock);
1122 if (u_notification == NULL) {
Cedric Le Goatera03fcb72006-10-02 02:17:26 -07001123 if (info->notify_owner == task_tgid(current)) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001124 remove_notification(info);
1125 inode->i_atime = inode->i_ctime = CURRENT_TIME;
1126 }
Cedric Le Goatera03fcb72006-10-02 02:17:26 -07001127 } else if (info->notify_owner != NULL) {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001128 ret = -EBUSY;
1129 } else {
1130 switch (notification.sigev_notify) {
1131 case SIGEV_NONE:
1132 info->notify.sigev_notify = SIGEV_NONE;
1133 break;
1134 case SIGEV_THREAD:
1135 info->notify_sock = sock;
1136 info->notify_cookie = nc;
1137 sock = NULL;
1138 nc = NULL;
1139 info->notify.sigev_notify = SIGEV_THREAD;
1140 break;
1141 case SIGEV_SIGNAL:
1142 info->notify.sigev_signo = notification.sigev_signo;
1143 info->notify.sigev_value = notification.sigev_value;
1144 info->notify.sigev_notify = SIGEV_SIGNAL;
1145 break;
1146 }
Cedric Le Goatera03fcb72006-10-02 02:17:26 -07001147
1148 info->notify_owner = get_pid(task_tgid(current));
Linus Torvalds1da177e2005-04-16 15:20:36 -07001149 inode->i_atime = inode->i_ctime = CURRENT_TIME;
1150 }
1151 spin_unlock(&info->lock);
1152out_fput:
1153 fput(filp);
1154out:
1155 if (sock) {
1156 netlink_detachskb(sock, nc);
1157 } else if (nc) {
1158 dev_kfree_skb(nc);
1159 }
1160 return ret;
1161}
1162
Heiko Carstensc4ea37c2009-01-14 14:14:28 +01001163SYSCALL_DEFINE3(mq_getsetattr, mqd_t, mqdes,
1164 const struct mq_attr __user *, u_mqstat,
1165 struct mq_attr __user *, u_omqstat)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001166{
1167 int ret;
1168 struct mq_attr mqstat, omqstat;
1169 struct file *filp;
1170 struct inode *inode;
1171 struct mqueue_inode_info *info;
1172
1173 if (u_mqstat != NULL) {
1174 if (copy_from_user(&mqstat, u_mqstat, sizeof(struct mq_attr)))
1175 return -EFAULT;
1176 if (mqstat.mq_flags & (~O_NONBLOCK))
1177 return -EINVAL;
1178 }
1179
Linus Torvalds1da177e2005-04-16 15:20:36 -07001180 filp = fget(mqdes);
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001181 if (!filp) {
1182 ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001183 goto out;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001184 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001185
Josef Sipek6d630792006-12-08 02:37:11 -08001186 inode = filp->f_path.dentry->d_inode;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001187 if (unlikely(filp->f_op != &mqueue_file_operations)) {
1188 ret = -EBADF;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001189 goto out_fput;
André Goddard Rosa8d8ffef2010-02-23 04:04:26 -03001190 }
Linus Torvalds1da177e2005-04-16 15:20:36 -07001191 info = MQUEUE_I(inode);
1192
1193 spin_lock(&info->lock);
1194
1195 omqstat = info->attr;
1196 omqstat.mq_flags = filp->f_flags & O_NONBLOCK;
1197 if (u_mqstat) {
Al Viro73929062008-12-10 06:58:59 -05001198 audit_mq_getsetattr(mqdes, &mqstat);
Jonathan Corbetdb1dd4d2009-02-06 15:25:24 -07001199 spin_lock(&filp->f_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001200 if (mqstat.mq_flags & O_NONBLOCK)
1201 filp->f_flags |= O_NONBLOCK;
1202 else
1203 filp->f_flags &= ~O_NONBLOCK;
Jonathan Corbetdb1dd4d2009-02-06 15:25:24 -07001204 spin_unlock(&filp->f_lock);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001205
1206 inode->i_atime = inode->i_ctime = CURRENT_TIME;
1207 }
1208
1209 spin_unlock(&info->lock);
1210
1211 ret = 0;
1212 if (u_omqstat != NULL && copy_to_user(u_omqstat, &omqstat,
1213 sizeof(struct mq_attr)))
1214 ret = -EFAULT;
1215
1216out_fput:
1217 fput(filp);
1218out:
1219 return ret;
1220}
1221
Arjan van de Ven92e1d5b2007-02-12 00:55:39 -08001222static const struct inode_operations mqueue_dir_inode_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001223 .lookup = simple_lookup,
1224 .create = mqueue_create,
1225 .unlink = mqueue_unlink,
1226};
1227
Arjan van de Ven9a321442007-02-12 00:55:35 -08001228static const struct file_operations mqueue_file_operations = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001229 .flush = mqueue_flush_file,
1230 .poll = mqueue_poll_file,
1231 .read = mqueue_read_file,
Arnd Bergmann6038f372010-08-15 18:52:59 +02001232 .llseek = default_llseek,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001233};
1234
Alexey Dobriyanb87221d2009-09-21 17:01:09 -07001235static const struct super_operations mqueue_super_ops = {
Linus Torvalds1da177e2005-04-16 15:20:36 -07001236 .alloc_inode = mqueue_alloc_inode,
1237 .destroy_inode = mqueue_destroy_inode,
Al Viro6d8af642010-06-05 16:29:45 -04001238 .evict_inode = mqueue_evict_inode,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001239 .statfs = simple_statfs,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001240};
1241
1242static struct file_system_type mqueue_fs_type = {
1243 .name = "mqueue",
Al Viroceefda62010-07-26 13:16:50 +04001244 .mount = mqueue_mount,
Linus Torvalds1da177e2005-04-16 15:20:36 -07001245 .kill_sb = kill_litter_super,
1246};
1247
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -07001248int mq_init_ns(struct ipc_namespace *ns)
1249{
1250 ns->mq_queues_count = 0;
1251 ns->mq_queues_max = DFLT_QUEUESMAX;
1252 ns->mq_msg_max = DFLT_MSGMAX;
1253 ns->mq_msgsize_max = DFLT_MSGSIZEMAX;
1254
1255 ns->mq_mnt = kern_mount_data(&mqueue_fs_type, ns);
1256 if (IS_ERR(ns->mq_mnt)) {
1257 int err = PTR_ERR(ns->mq_mnt);
1258 ns->mq_mnt = NULL;
1259 return err;
1260 }
1261 return 0;
1262}
1263
1264void mq_clear_sbinfo(struct ipc_namespace *ns)
1265{
1266 ns->mq_mnt->mnt_sb->s_fs_info = NULL;
1267}
1268
1269void mq_put_mnt(struct ipc_namespace *ns)
1270{
Al Viro6f686572011-12-09 00:38:50 -05001271 kern_unmount(ns->mq_mnt);
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -07001272}
1273
Linus Torvalds1da177e2005-04-16 15:20:36 -07001274static int __init init_mqueue_fs(void)
1275{
1276 int error;
1277
1278 mqueue_inode_cachep = kmem_cache_create("mqueue_inode_cache",
1279 sizeof(struct mqueue_inode_info), 0,
Paul Mundt20c2df82007-07-20 10:11:58 +09001280 SLAB_HWCACHE_ALIGN, init_once);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001281 if (mqueue_inode_cachep == NULL)
1282 return -ENOMEM;
1283
André Goddard Rosa2329e392010-02-23 04:04:27 -03001284 /* ignore failures - they are not fatal */
Serge E. Hallynbdc8e5f2009-04-06 19:01:11 -07001285 mq_sysctl_table = mq_register_sysctl_table();
Linus Torvalds1da177e2005-04-16 15:20:36 -07001286
1287 error = register_filesystem(&mqueue_fs_type);
1288 if (error)
1289 goto out_sysctl;
1290
Serge E. Hallyn7eafd7c2009-04-06 19:01:10 -07001291 spin_lock_init(&mq_lock);
1292
Al Viro6f686572011-12-09 00:38:50 -05001293 error = mq_init_ns(&init_ipc_ns);
1294 if (error)
Linus Torvalds1da177e2005-04-16 15:20:36 -07001295 goto out_filesystem;
Linus Torvalds1da177e2005-04-16 15:20:36 -07001296
Linus Torvalds1da177e2005-04-16 15:20:36 -07001297 return 0;
1298
1299out_filesystem:
1300 unregister_filesystem(&mqueue_fs_type);
1301out_sysctl:
1302 if (mq_sysctl_table)
1303 unregister_sysctl_table(mq_sysctl_table);
Alexey Dobriyan1a1d92c2006-09-27 01:49:40 -07001304 kmem_cache_destroy(mqueue_inode_cachep);
Linus Torvalds1da177e2005-04-16 15:20:36 -07001305 return error;
1306}
1307
1308__initcall(init_mqueue_fs);