/* * kernel/freezer.c - Function to freeze a process * * Originally from kernel/power/process.c */ #include #include #include #include #include #include /* total number of freezing conditions in effect */ atomic_t system_freezing_cnt = ATOMIC_INIT(0); EXPORT_SYMBOL(system_freezing_cnt); /* indicate whether PM freezing is in effect, protected by pm_mutex */ bool pm_freezing; bool pm_nosig_freezing; /* * Temporary export for the deadlock workaround in ata_scsi_hotplug(). * Remove once the hack becomes unnecessary. */ EXPORT_SYMBOL_GPL(pm_freezing); /* protects freezing and frozen transitions */ static DEFINE_SPINLOCK(freezer_lock); /** * freezing_slow_path - slow path for testing whether a task needs to be frozen * @p: task to be tested * * This function is called by freezing() if system_freezing_cnt isn't zero * and tests whether @p needs to enter and stay in frozen state. Can be * called under any context. The freezers are responsible for ensuring the * target tasks see the updated state. */ bool freezing_slow_path(struct task_struct *p) { if (p->flags & (PF_NOFREEZE | PF_SUSPEND_TASK)) return false; if (test_tsk_thread_flag(p, TIF_MEMDIE)) return false; if (pm_nosig_freezing || cgroup_freezing(p)) return true; if (pm_freezing && !(p->flags & PF_KTHREAD)) return true; return false; } EXPORT_SYMBOL(freezing_slow_path); /* Refrigerator is place where frozen processes are stored :-). */ bool __refrigerator(bool check_kthr_stop) { /* Hmm, should we be allowed to suspend when there are realtime processes around? */ bool was_frozen = false; long save = current->state; pr_debug("%s entered refrigerator\n", current->comm); for (;;) { set_current_state(TASK_UNINTERRUPTIBLE); spin_lock_irq(&freezer_lock); current->flags |= PF_FROZEN; if (!freezing(current) || (check_kthr_stop && kthread_should_stop())) current->flags &= ~PF_FROZEN; spin_unlock_irq(&freezer_lock); if (!(current->flags & PF_FROZEN)) break; was_frozen = true; schedule(); } pr_debug("%s left refrigerator\n", current->comm); /* * Restore saved task state before returning. The mb'd version * needs to be used; otherwise, it might silently break * synchronization which depends on ordered task state change. */ set_current_state(save); return was_frozen; } EXPORT_SYMBOL(__refrigerator); static void fake_signal_wake_up(struct task_struct *p) { unsigned long flags; if (lock_task_sighand(p, &flags)) { signal_wake_up(p, 0); unlock_task_sighand(p, &flags); } } /** * freeze_task - send a freeze request to given task * @p: task to send the request to * * If @p is freezing, the freeze request is sent either by sending a fake * signal (if it's not a kernel thread) or waking it up (if it's a kernel * thread). * * RETURNS: * %false, if @p is not freezing or already frozen; %true, otherwise */ bool freeze_task(struct task_struct *p) { unsigned long flags; /* * This check can race with freezer_do_not_count, but worst case that * will result in an extra wakeup being sent to the task. It does not * race with freezer_count(), the barriers in freezer_count() and * freezer_should_skip() ensure that either freezer_count() sees * freezing == true in try_to_freeze() and freezes, or * freezer_should_skip() sees !PF_FREEZE_SKIP and freezes the task * normally. */ if (freezer_should_skip(p)) return false; spin_lock_irqsave(&freezer_lock, flags); if (!freezing(p) || frozen(p)) { spin_unlock_irqrestore(&freezer_lock, flags); return false; } if (!(p->flags & PF_KTHREAD)) fake_signal_wake_up(p); else wake_up_state(p, TASK_INTERRUPTIBLE); spin_unlock_irqrestore(&freezer_lock, flags); return true; } void __thaw_task(struct task_struct *p) { unsigned long flags; spin_lock_irqsave(&freezer_lock, flags); if (frozen(p)) wake_up_process(p); spin_unlock_irqrestore(&freezer_lock, flags); } /** * set_freezable - make %current freezable * * Mark %current freezable and enter refrigerator if necessary. */ bool set_freezable(void) { might_sleep(); /* * Modify flags while holding freezer_lock. This ensures the * freezer notices that we aren't frozen yet or the freezing * condition is visible to try_to_freeze() below. */ spin_lock_irq(&freezer_lock); current->flags &= ~PF_NOFREEZE; spin_unlock_irq(&freezer_lock); return try_to_freeze(); } EXPORT_SYMBOL(set_freezable); authorAleksander Morgado <aleksander@aleksander.es>2017-01-18 21:31:31 +0100 committerJohan Hovold <johan@kernel.org>2017-01-19 09:08:37 +0100 commit24d615a694d649aa2e167c3f97f62bdad07e3f84 (patch) tree2fe33c115bdec6bf4b01e27afd90bb16fa668e22 /include/crypto/pcrypt.h parent49def1853334396f948dcb4cedb9347abb318df5 (diff)
USB: serial: qcserial: add Dell DW5570 QDL
The Dell DW5570 is a re-branded Sierra Wireless MC8805 which will by default boot with vid 0x413c and pid 0x81a3. When triggered QDL download mode, the device switches to pid 0x81a6 and provides the standard TTY used for firmware upgrade. Cc: <stable@vger.kernel.org> Signed-off-by: Aleksander Morgado <aleksander@aleksander.es> Signed-off-by: Johan Hovold <johan@kernel.org>
Diffstat (limited to 'include/crypto/pcrypt.h')