/*
* Send or receive packet.
*/
static int sock_xmit(struct socket *sock, int send, void *buf, int size,
int msg_flags)
{
int result;
struct msghdr msg;
struct kvec iov;
sigset_t blocked, oldset;
/* Allow interception of SIGKILL only
* Don't allow other signals to interrupt the transmission */
siginitsetinv(&blocked, sigmask(SIGKILL));
sigprocmask(SIG_SETMASK, &blocked, &oldset);
do {
sock->sk->sk_allocation = GFP_NOIO;
iov.iov_base = buf;
iov.iov_len = size;
msg.msg_name = NULL;
msg.msg_namelen = 0;
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_flags = msg_flags | MSG_NOSIGNAL;
if (send)
result = kernel_sendmsg(sock, &msg, &iov, 1, size);
else
result = kernel_recvmsg(sock, &msg, &iov, 1, size, 0);
if (signal_pending(current)) {
siginfo_t info;
printk(KERN_WARNING "nbd (pid %d: %s) got signal %d\n",
current->pid, current->comm,
dequeue_signal_lock(current, ¤t->blocked, &info));
result = -EINTR;
break;
}
if (result <= 0) {
if (result == 0)
result = -EPIPE; /* short read */
break;
}
size -= result;
buf += result;
} while (size > 0);
sigprocmask(SIG_SETMASK, &oldset, NULL);
return result;
}
static int htckovsky_oj_thread(void *v) {
struct completion exit;
siginfo_t info;
daemonize("oj_thread");
allow_signal(SIGKILL);
init_completion(&exit);
while (true) {
if (signal_pending(current)) {
if (dequeue_signal_lock(current, ¤t->blocked, &info)
== SIGKILL) {
goto done;
}
}
htckovsky_oj_work(NULL);
msleep(OJ_POLL_DELAY);
}
done:
complete_and_exit(&exit, 0);
}
/*
* Send or receive packet.
*/
static int sock_xmit(struct nbd_device *nbd, int send, void *buf, int size,
int msg_flags)
{
struct socket *sock = nbd->sock;
int result;
struct msghdr msg;
struct kvec iov;
sigset_t blocked, oldset;
if (unlikely(!sock)) {
dev_err(disk_to_dev(nbd->disk),
"Attempted %s on closed socket in sock_xmit\n",
(send ? "send" : "recv"));
return -EINVAL;
}
/* Allow interception of SIGKILL only
* Don't allow other signals to interrupt the transmission */
siginitsetinv(&blocked, sigmask(SIGKILL));
sigprocmask(SIG_SETMASK, &blocked, &oldset);
do {
sock->sk->sk_allocation = GFP_NOIO;
iov.iov_base = buf;
iov.iov_len = size;
msg.msg_name = NULL;
msg.msg_namelen = 0;
msg.msg_control = NULL;
msg.msg_controllen = 0;
msg.msg_flags = msg_flags | MSG_NOSIGNAL;
if (send) {
struct timer_list ti;
if (nbd->xmit_timeout) {
init_timer(&ti);
ti.function = nbd_xmit_timeout;
ti.data = (unsigned long)current;
ti.expires = jiffies + nbd->xmit_timeout;
add_timer(&ti);
}
result = kernel_sendmsg(sock, &msg, &iov, 1, size);
if (nbd->xmit_timeout)
del_timer_sync(&ti);
} else
result = kernel_recvmsg(sock, &msg, &iov, 1, size,
msg.msg_flags);
if (signal_pending(current)) {
siginfo_t info;
printk(KERN_WARNING "nbd (pid %d: %s) got signal %d\n",
task_pid_nr(current), current->comm,
dequeue_signal_lock(current, ¤t->blocked, &info));
result = -EINTR;
sock_shutdown(nbd, !send);
break;
}
if (result <= 0) {
if (result == 0)
result = -EPIPE; /* short read */
break;
}
size -= result;
buf += result;
} while (size > 0);
sigprocmask(SIG_SETMASK, &oldset, NULL);
return result;
}
static int jffs2_garbage_collect_thread(void *_c)
{
struct jffs2_sb_info *c = _c;
daemonize("jffs2_gcd_mtd%d", c->mtd->index);
allow_signal(SIGKILL);
allow_signal(SIGSTOP);
allow_signal(SIGCONT);
c->gc_task = current;
complete(&c->gc_thread_start);
set_user_nice(current, 10);
for (;;) {
allow_signal(SIGHUP);
if (!jffs2_thread_should_wake(c)) {
set_current_state (TASK_INTERRUPTIBLE);
D1(printk(KERN_DEBUG "jffs2_garbage_collect_thread sleeping...\n"));
/* Yes, there's a race here; we checked jffs2_thread_should_wake()
before setting current->state to TASK_INTERRUPTIBLE. But it doesn't
matter - We don't care if we miss a wakeup, because the GC thread
is only an optimisation anyway. */
schedule();
}
if (try_to_freeze())
continue;
cond_resched();
/* Put_super will send a SIGKILL and then wait on the sem.
*/
while (signal_pending(current)) {
siginfo_t info;
unsigned long signr;
signr = dequeue_signal_lock(current, ¤t->blocked, &info);
switch(signr) {
case SIGSTOP:
D1(printk(KERN_DEBUG "jffs2_garbage_collect_thread(): SIGSTOP received.\n"));
set_current_state(TASK_STOPPED);
schedule();
break;
case SIGKILL:
D1(printk(KERN_DEBUG "jffs2_garbage_collect_thread(): SIGKILL received.\n"));
goto die;
case SIGHUP:
D1(printk(KERN_DEBUG "jffs2_garbage_collect_thread(): SIGHUP received.\n"));
break;
default:
D1(printk(KERN_DEBUG "jffs2_garbage_collect_thread(): signal %ld received\n", signr));
}
}
/* We don't want SIGHUP to interrupt us. STOP and KILL are OK though. */
disallow_signal(SIGHUP);
D1(printk(KERN_DEBUG "jffs2_garbage_collect_thread(): pass\n"));
if (jffs2_garbage_collect_pass(c) == -ENOSPC) {
printk(KERN_NOTICE "No space for garbage collection. Aborting GC thread\n");
goto die;
}
}
die:
spin_lock(&c->erase_completion_lock);
c->gc_task = NULL;
spin_unlock(&c->erase_completion_lock);
complete_and_exit(&c->gc_thread_exit, 0);
}
static int jffs2_garbage_collect_thread(void *_c)
{
struct jffs2_sb_info *c = _c;
allow_signal(SIGKILL);
allow_signal(SIGSTOP);
allow_signal(SIGCONT);
c->gc_task = current;
complete(&c->gc_thread_start);
set_user_nice(current, 10);
set_freezable();
for (;;) {
allow_signal(SIGHUP);
again:
spin_lock(&c->erase_completion_lock);
if (!jffs2_thread_should_wake(c)) {
set_current_state (TASK_INTERRUPTIBLE);
spin_unlock(&c->erase_completion_lock);
jffs2_dbg(1, "%s(): sleeping...\n", __func__);
schedule();
} else
spin_unlock(&c->erase_completion_lock);
/* Problem - immediately after bootup, the GCD spends a lot
* of time in places like jffs2_kill_fragtree(); so much so
* that userspace processes (like gdm and X) are starved
* despite plenty of cond_resched()s and renicing. Yield()
* doesn't help, either (presumably because userspace and GCD
* are generally competing for a higher latency resource -
* disk).
* This forces the GCD to slow the hell down. Pulling an
* inode in with read_inode() is much preferable to having
* the GC thread get there first. */
schedule_timeout_interruptible(msecs_to_jiffies(50));
if (kthread_should_stop()) {
jffs2_dbg(1, "%s(): kthread_stop() called\n", __func__);
goto die;
}
/* Put_super will send a SIGKILL and then wait on the sem.
*/
while (signal_pending(current) || freezing(current)) {
siginfo_t info;
unsigned long signr;
if (try_to_freeze())
goto again;
signr = dequeue_signal_lock(current, ¤t->blocked, &info);
switch(signr) {
case SIGSTOP:
jffs2_dbg(1, "%s(): SIGSTOP received\n",
__func__);
set_current_state(TASK_STOPPED);
schedule();
break;
case SIGKILL:
jffs2_dbg(1, "%s(): SIGKILL received\n",
__func__);
goto die;
case SIGHUP:
jffs2_dbg(1, "%s(): SIGHUP received\n",
__func__);
break;
default:
jffs2_dbg(1, "%s(): signal %ld received\n",
__func__, signr);
}
}
/* We don't want SIGHUP to interrupt us. STOP and KILL are OK though. */
disallow_signal(SIGHUP);
jffs2_dbg(1, "%s(): pass\n", __func__);
if (jffs2_garbage_collect_pass(c) == -ENOSPC) {
pr_notice("No space for garbage collection. Aborting GC thread\n");
goto die;
}
}
die:
spin_lock(&c->erase_completion_lock);
c->gc_task = NULL;
spin_unlock(&c->erase_completion_lock);
complete_and_exit(&c->gc_thread_exit, 0);
}
static int jffs2_garbage_collect_thread(void *_c)
{
struct jffs2_sb_info *c = _c;
allow_signal(SIGKILL);
allow_signal(SIGSTOP);
allow_signal(SIGCONT);
c->gc_task = current;
complete(&c->gc_thread_start);
set_user_nice(current, 10);
set_freezable();
for (;;) {
allow_signal(SIGHUP);
again:
spin_lock(&c->erase_completion_lock);
if (!jffs2_thread_should_wake(c)) {
set_current_state (TASK_INTERRUPTIBLE);
spin_unlock(&c->erase_completion_lock);
jffs2_dbg(1, "%s(): sleeping...\n", __func__);
schedule();
} else
spin_unlock(&c->erase_completion_lock);
schedule_timeout_interruptible(msecs_to_jiffies(50));
if (kthread_should_stop()) {
jffs2_dbg(1, "%s(): kthread_stop() called\n", __func__);
goto die;
}
while (signal_pending(current) || freezing(current)) {
siginfo_t info;
unsigned long signr;
if (try_to_freeze())
goto again;
signr = dequeue_signal_lock(current, ¤t->blocked, &info);
switch(signr) {
case SIGSTOP:
jffs2_dbg(1, "%s(): SIGSTOP received\n",
__func__);
set_current_state(TASK_STOPPED);
schedule();
break;
case SIGKILL:
jffs2_dbg(1, "%s(): SIGKILL received\n",
__func__);
goto die;
case SIGHUP:
jffs2_dbg(1, "%s(): SIGHUP received\n",
__func__);
break;
default:
jffs2_dbg(1, "%s(): signal %ld received\n",
__func__, signr);
}
}
disallow_signal(SIGHUP);
jffs2_dbg(1, "%s(): pass\n", __func__);
if (jffs2_garbage_collect_pass(c) == -ENOSPC) {
pr_notice("No space for garbage collection. Aborting GC thread\n");
goto die;
}
}
die:
spin_lock(&c->erase_completion_lock);
c->gc_task = NULL;
spin_unlock(&c->erase_completion_lock);
complete_and_exit(&c->gc_thread_exit, 0);
}