lkml.org 
[lkml]   [2014]   [Aug]   [23]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Date
Subject[PATCH] V1 2/2] ipc: let message queues use SIGEV_THREAD_ID with mq_notify
diff --git a/ipc/mqueue.c b/ipc/mqueue.c
index 4fcf39a..8ca70a2 100644
--- a/ipc/mqueue.c
+++ b/ipc/mqueue.c
@@ -88,7 +88,7 @@ struct mqueue_inode_info {
static const struct inode_operations mqueue_dir_inode_operations;
static const struct file_operations mqueue_file_operations;
static const struct super_operations mqueue_super_ops;
-static void remove_notification(struct mqueue_inode_info *info);
+static bool maybe_remove_notification(struct mqueue_inode_info *info);

static struct kmem_cache *mqueue_inode_cachep;

@@ -495,7 +495,8 @@ static ssize_t mqueue_read_file(struct file *filp, char
__user *u_data,
info->qsize,
info->notify_owner ? info->notify.sigev_notify : 0,
(info->notify_owner &&
- info->notify.sigev_notify == SIGEV_SIGNAL) ?
+ (info->notify.sigev_notify == SIGEV_SIGNAL ||
+ info->notify.sigev_notify == SIGEV_THREAD_ID)) ?
info->notify.sigev_signo : 0,
pid_vnr(info->notify_owner));
spin_unlock(&info->lock);
@@ -515,8 +516,8 @@ static int mqueue_flush_file(struct file *filp, fl_owner_t id)
struct mqueue_inode_info *info = MQUEUE_I(file_inode(filp));

spin_lock(&info->lock);
- if (task_tgid(current) == info->notify_owner)
- remove_notification(info);
+
+ maybe_remove_notification(info);

spin_unlock(&info->lock);
return 0;
@@ -642,6 +643,7 @@ static void __do_notify(struct mqueue_inode_info *info)
case SIGEV_NONE:
break;
case SIGEV_SIGNAL:
+ case SIGEV_THREAD_ID:
/* sends signal */

sig_i.si_signo = info->notify.sigev_signo;
@@ -684,8 +686,24 @@ static int prepare_timeout(const struct timespec __user
*u_abs_timeout,
return 0;
}

-static void remove_notification(struct mqueue_inode_info *info)
+static bool maybe_remove_notification(struct mqueue_inode_info *info)
{
+ struct pid *pid;
+
+ switch (info->notify.sigev_notify) {
+ case SIGEV_THREAD_ID:
+ pid = task_pid(current);
+ break;
+
+ default:
+ pid = task_tgid(current);
+ break;
+ }
+
+ if (pid != info->notify_owner) {
+ return false;
+ }
+
if (info->notify_owner != NULL &&
info->notify.sigev_notify == SIGEV_THREAD) {
set_cookie(info->notify_cookie, NOTIFY_REMOVED);
@@ -695,6 +713,8 @@ static void remove_notification(struct mqueue_inode_info *info)
put_user_ns(info->notify_user_ns);
info->notify_owner = NULL;
info->notify_user_ns = NULL;
+
+ return true;
}

static int mq_attr_ok(struct ipc_namespace *ipc_ns, struct mq_attr *attr)
@@ -1203,12 +1223,18 @@ SYSCALL_DEFINE2(mq_notify, mqd_t, mqdes,
if (u_notification != NULL) {
if (unlikely(notification.sigev_notify != SIGEV_NONE &&
notification.sigev_notify != SIGEV_SIGNAL &&
- notification.sigev_notify != SIGEV_THREAD))
+ notification.sigev_notify != SIGEV_THREAD &&
+ notification.sigev_notify != SIGEV_THREAD_ID))
return -EINVAL;
- if (notification.sigev_notify == SIGEV_SIGNAL &&
+ if ((notification.sigev_notify == SIGEV_SIGNAL ||
+ notification.sigev_notify == SIGEV_THREAD_ID) &&
!valid_signal(notification.sigev_signo)) {
return -EINVAL;
}
+ if (notification.sigev_notify == SIGEV_THREAD_ID &&
+ notification.sigev_notify_thread_id <= 0) {
+ return -EINVAL;
+ }
if (notification.sigev_notify == SIGEV_THREAD) {
long timeo;

@@ -1270,8 +1296,7 @@ retry:
ret = 0;
spin_lock(&info->lock);
if (u_notification == NULL) {
- if (info->notify_owner == task_tgid(current)) {
- remove_notification(info);
+ if (maybe_remove_notification(info)) {
inode->i_atime = inode->i_ctime = CURRENT_TIME;
}
} else if (info->notify_owner != NULL) {
@@ -1286,16 +1311,39 @@ retry:
info->notify_cookie = nc;
sock = NULL;
nc = NULL;
+ info->notify_owner = get_pid(task_tgid(current));
info->notify.sigev_notify = SIGEV_THREAD;
break;
case SIGEV_SIGNAL:
info->notify.sigev_signo = notification.sigev_signo;
info->notify.sigev_value = notification.sigev_value;
+ info->notify_owner = get_pid(task_tgid(current));
info->notify.sigev_notify = SIGEV_SIGNAL;
break;
+ case SIGEV_THREAD_ID:
+ {
+ struct pid *tid;
+ pid_t tid_nr;
+
+ tid_nr = notification.sigev_notify_thread_id;
+
+ info->notify.sigev_signo = notification.sigev_signo;
+ info->notify.sigev_value = notification.sigev_value;
+
+ tid = find_get_pid(tid_nr);
+ if (NULL == tid) {
+ ret = -ESRCH;
+ goto out_fput;
+ }
+
+ info->notify.sigev_notify_thread_id = tid_nr;
+
+ info->notify_owner = tid;
+ info->notify.sigev_notify = SIGEV_THREAD_ID;
+ break;
+ }
}

- info->notify_owner = get_pid(task_tgid(current));
info->notify_user_ns = get_user_ns(current_user_ns());
inode->i_atime = inode->i_ctime = CURRENT_TIME;
}


\
 
 \ /
  Last update: 2014-08-24 06:01    [W:0.033 / U:0.828 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site