devres: fix possible use after free
[linux-2.6.git] / kernel / irq / manage.c
index dd4e5c2..0a7840a 100644 (file)
 
 #include "internals.h"
 
+#ifdef CONFIG_IRQ_FORCED_THREADING
+__read_mostly bool force_irqthreads;
+
+static int __init setup_forced_irqthreads(char *arg)
+{
+       force_irqthreads = true;
+       return 0;
+}
+early_param("threadirqs", setup_forced_irqthreads);
+#endif
+
 /**
  *     synchronize_irq - wait for pending IRQ handlers (on other CPUs)
  *     @irq: interrupt number to wait for
@@ -30,7 +41,7 @@
 void synchronize_irq(unsigned int irq)
 {
        struct irq_desc *desc = irq_to_desc(irq);
-       unsigned int status;
+       bool inprogress;
 
        if (!desc)
                return;
@@ -42,16 +53,16 @@ void synchronize_irq(unsigned int irq)
                 * Wait until we're out of the critical section.  This might
                 * give the wrong answer due to the lack of memory barriers.
                 */
-               while (desc->status & IRQ_INPROGRESS)
+               while (irqd_irq_inprogress(&desc->irq_data))
                        cpu_relax();
 
                /* Ok, that indicated we're done: double-check carefully. */
                raw_spin_lock_irqsave(&desc->lock, flags);
-               status = desc->status;
+               inprogress = irqd_irq_inprogress(&desc->irq_data);
                raw_spin_unlock_irqrestore(&desc->lock, flags);
 
                /* Oops, that failed? */
-       } while (status & IRQ_INPROGRESS);
+       } while (inprogress);
 
        /*
         * We made sure that no hardirq handler is running. Now verify
@@ -73,8 +84,8 @@ int irq_can_set_affinity(unsigned int irq)
 {
        struct irq_desc *desc = irq_to_desc(irq);
 
-       if (CHECK_IRQ_PER_CPU(desc->status) || !desc->irq_data.chip ||
-           !desc->irq_data.chip->irq_set_affinity)
+       if (!desc || !irqd_can_balance(&desc->irq_data) ||
+           !desc->irq_data.chip || !desc->irq_data.chip->irq_set_affinity)
                return 0;
 
        return 1;
@@ -101,13 +112,13 @@ void irq_set_thread_affinity(struct irq_desc *desc)
 }
 
 #ifdef CONFIG_GENERIC_PENDING_IRQ
-static inline bool irq_can_move_pcntxt(struct irq_desc *desc)
+static inline bool irq_can_move_pcntxt(struct irq_data *data)
 {
-       return desc->status & IRQ_MOVE_PCNTXT;
+       return irqd_can_move_in_process_context(data);
 }
-static inline bool irq_move_pending(struct irq_desc *desc)
+static inline bool irq_move_pending(struct irq_data *data)
 {
-       return desc->status & IRQ_MOVE_PENDING;
+       return irqd_is_setaffinity_pending(data);
 }
 static inline void
 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask)
@@ -120,43 +131,34 @@ irq_get_pending(struct cpumask *mask, struct irq_desc *desc)
        cpumask_copy(mask, desc->pending_mask);
 }
 #else
-static inline bool irq_can_move_pcntxt(struct irq_desc *desc) { return true; }
-static inline bool irq_move_pending(struct irq_desc *desc) { return false; }
+static inline bool irq_can_move_pcntxt(struct irq_data *data) { return true; }
+static inline bool irq_move_pending(struct irq_data *data) { return false; }
 static inline void
 irq_copy_pending(struct irq_desc *desc, const struct cpumask *mask) { }
 static inline void
 irq_get_pending(struct cpumask *mask, struct irq_desc *desc) { }
 #endif
 
-/**
- *     irq_set_affinity - Set the irq affinity of a given irq
- *     @irq:           Interrupt to set affinity
- *     @cpumask:       cpumask
- *
- */
-int irq_set_affinity(unsigned int irq, const struct cpumask *mask)
+int __irq_set_affinity_locked(struct irq_data *data, const struct cpumask *mask)
 {
-       struct irq_desc *desc = irq_to_desc(irq);
-       struct irq_chip *chip = desc->irq_data.chip;
-       unsigned long flags;
+       struct irq_chip *chip = irq_data_get_irq_chip(data);
+       struct irq_desc *desc = irq_data_to_desc(data);
        int ret = 0;
 
-       if (!chip->irq_set_affinity)
+       if (!chip || !chip->irq_set_affinity)
                return -EINVAL;
 
-       raw_spin_lock_irqsave(&desc->lock, flags);
-
-       if (irq_can_move_pcntxt(desc)) {
-               ret = chip->irq_set_affinity(&desc->irq_data, mask, false);
+       if (irq_can_move_pcntxt(data)) {
+               ret = chip->irq_set_affinity(data, mask, false);
                switch (ret) {
                case IRQ_SET_MASK_OK:
-                       cpumask_copy(desc->irq_data.affinity, mask);
+                       cpumask_copy(data->affinity, mask);
                case IRQ_SET_MASK_OK_NOCOPY:
                        irq_set_thread_affinity(desc);
                        ret = 0;
                }
        } else {
-               desc->status |= IRQ_MOVE_PENDING;
+               irqd_set_move_pending(data);
                irq_copy_pending(desc, mask);
        }
 
@@ -164,23 +166,41 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *mask)
                kref_get(&desc->affinity_notify->kref);
                schedule_work(&desc->affinity_notify->work);
        }
-       desc->status |= IRQ_AFFINITY_SET;
-       raw_spin_unlock_irqrestore(&desc->lock, flags);
+       irqd_set(data, IRQD_AFFINITY_SET);
+
        return ret;
 }
 
-int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
+/**
+ *     irq_set_affinity - Set the irq affinity of a given irq
+ *     @irq:           Interrupt to set affinity
+ *     @mask:          cpumask
+ *
+ */
+int irq_set_affinity(unsigned int irq, const struct cpumask *mask)
 {
        struct irq_desc *desc = irq_to_desc(irq);
        unsigned long flags;
+       int ret;
 
        if (!desc)
                return -EINVAL;
 
        raw_spin_lock_irqsave(&desc->lock, flags);
-       desc->affinity_hint = m;
+       ret =  __irq_set_affinity_locked(irq_desc_get_irq_data(desc), mask);
        raw_spin_unlock_irqrestore(&desc->lock, flags);
+       return ret;
+}
 
+int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
+{
+       unsigned long flags;
+       struct irq_desc *desc = irq_get_desc_lock(irq, &flags);
+
+       if (!desc)
+               return -EINVAL;
+       desc->affinity_hint = m;
+       irq_put_desc_unlock(desc, flags);
        return 0;
 }
 EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
@@ -197,7 +217,7 @@ static void irq_affinity_notify(struct work_struct *work)
                goto out;
 
        raw_spin_lock_irqsave(&desc->lock, flags);
-       if (irq_move_pending(desc))
+       if (irq_move_pending(&desc->irq_data))
                irq_get_pending(cpumask, desc);
        else
                cpumask_copy(cpumask, desc->irq_data.affinity);
@@ -272,12 +292,12 @@ setup_affinity(unsigned int irq, struct irq_desc *desc, struct cpumask *mask)
         * Preserve an userspace affinity setup, but make sure that
         * one of the targets is online.
         */
-       if (desc->status & (IRQ_AFFINITY_SET)) {
+       if (irqd_has_set(&desc->irq_data, IRQD_AFFINITY_SET)) {
                if (cpumask_intersects(desc->irq_data.affinity,
                                       cpu_online_mask))
                        set = desc->irq_data.affinity;
                else
-                       desc->status &= ~IRQ_AFFINITY_SET;
+                       irqd_clear(&desc->irq_data, IRQD_AFFINITY_SET);
        }
 
        cpumask_and(mask, cpu_online_mask, set);
@@ -326,13 +346,25 @@ void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend)
        if (suspend) {
                if (!desc->action || (desc->action->flags & IRQF_NO_SUSPEND))
                        return;
-               desc->status |= IRQ_SUSPENDED;
+               desc->istate |= IRQS_SUSPENDED;
        }
 
        if (!desc->depth++)
                irq_disable(desc);
 }
 
+static int __disable_irq_nosync(unsigned int irq)
+{
+       unsigned long flags;
+       struct irq_desc *desc = irq_get_desc_buslock(irq, &flags);
+
+       if (!desc)
+               return -EINVAL;
+       __disable_irq(desc, irq, false);
+       irq_put_desc_busunlock(desc, flags);
+       return 0;
+}
+
 /**
  *     disable_irq_nosync - disable an irq without waiting
  *     @irq: Interrupt to disable
@@ -346,17 +378,7 @@ void __disable_irq(struct irq_desc *desc, unsigned int irq, bool suspend)
  */
 void disable_irq_nosync(unsigned int irq)
 {
-       struct irq_desc *desc = irq_to_desc(irq);
-       unsigned long flags;
-
-       if (!desc)
-               return;
-
-       chip_bus_lock(desc);
-       raw_spin_lock_irqsave(&desc->lock, flags);
-       __disable_irq(desc, irq, false);
-       raw_spin_unlock_irqrestore(&desc->lock, flags);
-       chip_bus_sync_unlock(desc);
+       __disable_irq_nosync(irq);
 }
 EXPORT_SYMBOL(disable_irq_nosync);
 
@@ -374,13 +396,7 @@ EXPORT_SYMBOL(disable_irq_nosync);
  */
 void disable_irq(unsigned int irq)
 {
-       struct irq_desc *desc = irq_to_desc(irq);
-
-       if (!desc)
-               return;
-
-       disable_irq_nosync(irq);
-       if (desc->action)
+       if (!__disable_irq_nosync(irq))
                synchronize_irq(irq);
 }
 EXPORT_SYMBOL(disable_irq);
@@ -388,7 +404,7 @@ EXPORT_SYMBOL(disable_irq);
 void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume)
 {
        if (resume) {
-               if (!(desc->status & IRQ_SUSPENDED)) {
+               if (!(desc->istate & IRQS_SUSPENDED)) {
                        if (!desc->action)
                                return;
                        if (!(desc->action->flags & IRQF_FORCE_RESUME))
@@ -396,7 +412,7 @@ void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume)
                        /* Pretend that it got disabled ! */
                        desc->depth++;
                }
-               desc->status &= ~IRQ_SUSPENDED;
+               desc->istate &= ~IRQS_SUSPENDED;
        }
 
        switch (desc->depth) {
@@ -405,10 +421,10 @@ void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume)
                WARN(1, KERN_WARNING "Unbalanced enable for IRQ %d\n", irq);
                break;
        case 1: {
-               if (desc->status & IRQ_SUSPENDED)
+               if (desc->istate & IRQS_SUSPENDED)
                        goto err_out;
                /* Prevent probing on this irq: */
-               desc->status |= IRQ_NOPROBE;
+               irq_settings_set_noprobe(desc);
                irq_enable(desc);
                check_irq_resend(desc, irq);
                /* fall-through */
@@ -431,21 +447,18 @@ void __enable_irq(struct irq_desc *desc, unsigned int irq, bool resume)
  */
 void enable_irq(unsigned int irq)
 {
-       struct irq_desc *desc = irq_to_desc(irq);
        unsigned long flags;
+       struct irq_desc *desc = irq_get_desc_buslock(irq, &flags);
 
        if (!desc)
                return;
-
        if (WARN(!desc->irq_data.chip,
                 KERN_ERR "enable_irq before setup/request_irq: irq %u\n", irq))
-               return;
+               goto out;
 
-       chip_bus_lock(desc);
-       raw_spin_lock_irqsave(&desc->lock, flags);
        __enable_irq(desc, irq, false);
-       raw_spin_unlock_irqrestore(&desc->lock, flags);
-       chip_bus_sync_unlock(desc);
+out:
+       irq_put_desc_busunlock(desc, flags);
 }
 EXPORT_SYMBOL(enable_irq);
 
@@ -474,22 +487,23 @@ static int set_irq_wake_real(unsigned int irq, unsigned int on)
  */
 int irq_set_irq_wake(unsigned int irq, unsigned int on)
 {
-       struct irq_desc *desc = irq_to_desc(irq);
        unsigned long flags;
+       struct irq_desc *desc = irq_get_desc_buslock(irq, &flags);
        int ret = 0;
 
+       if (!desc)
+               return -EINVAL;
+
        /* wakeup-capable irqs can be shared between drivers that
         * don't need to have the same sleep mode behaviors.
         */
-       chip_bus_lock(desc);
-       raw_spin_lock_irqsave(&desc->lock, flags);
        if (on) {
                if (desc->wake_depth++ == 0) {
                        ret = set_irq_wake_real(irq, on);
                        if (ret)
                                desc->wake_depth = 0;
                        else
-                               desc->status |= IRQ_WAKEUP;
+                               irqd_set(&desc->irq_data, IRQD_WAKEUP_STATE);
                }
        } else {
                if (desc->wake_depth == 0) {
@@ -499,12 +513,10 @@ int irq_set_irq_wake(unsigned int irq, unsigned int on)
                        if (ret)
                                desc->wake_depth = 1;
                        else
-                               desc->status &= ~IRQ_WAKEUP;
+                               irqd_clear(&desc->irq_data, IRQD_WAKEUP_STATE);
                }
        }
-
-       raw_spin_unlock_irqrestore(&desc->lock, flags);
-       chip_bus_sync_unlock(desc);
+       irq_put_desc_busunlock(desc, flags);
        return ret;
 }
 EXPORT_SYMBOL(irq_set_irq_wake);
@@ -516,43 +528,27 @@ EXPORT_SYMBOL(irq_set_irq_wake);
  */
 int can_request_irq(unsigned int irq, unsigned long irqflags)
 {
-       struct irq_desc *desc = irq_to_desc(irq);
-       struct irqaction *action;
        unsigned long flags;
+       struct irq_desc *desc = irq_get_desc_lock(irq, &flags);
+       int canrequest = 0;
 
        if (!desc)
                return 0;
 
-       if (desc->status & IRQ_NOREQUEST)
-               return 0;
-
-       raw_spin_lock_irqsave(&desc->lock, flags);
-       action = desc->action;
-       if (action)
-               if (irqflags & action->flags & IRQF_SHARED)
-                       action = NULL;
-
-       raw_spin_unlock_irqrestore(&desc->lock, flags);
-
-       return !action;
-}
-
-void compat_irq_chip_set_default_handler(struct irq_desc *desc)
-{
-       /*
-        * If the architecture still has not overriden
-        * the flow handler then zap the default. This
-        * should catch incorrect flow-type setting.
-        */
-       if (desc->handle_irq == &handle_bad_irq)
-               desc->handle_irq = NULL;
+       if (irq_settings_can_request(desc)) {
+               if (desc->action)
+                       if (irqflags & desc->action->flags & IRQF_SHARED)
+                               canrequest =1;
+       }
+       irq_put_desc_unlock(desc, flags);
+       return canrequest;
 }
 
 int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
                      unsigned long flags)
 {
-       int ret;
        struct irq_chip *chip = desc->irq_data.chip;
+       int ret, unmask = 0;
 
        if (!chip || !chip->irq_set_type) {
                /*
@@ -564,23 +560,41 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
                return 0;
        }
 
+       flags &= IRQ_TYPE_SENSE_MASK;
+
+       if (chip->flags & IRQCHIP_SET_TYPE_MASKED) {
+               if (!irqd_irq_masked(&desc->irq_data))
+                       mask_irq(desc);
+               if (!irqd_irq_disabled(&desc->irq_data))
+                       unmask = 1;
+       }
+
        /* caller masked out all except trigger mode flags */
        ret = chip->irq_set_type(&desc->irq_data, flags);
 
-       if (ret)
+       switch (ret) {
+       case IRQ_SET_MASK_OK:
+               irqd_clear(&desc->irq_data, IRQD_TRIGGER_MASK);
+               irqd_set(&desc->irq_data, flags);
+
+       case IRQ_SET_MASK_OK_NOCOPY:
+               flags = irqd_get_trigger_type(&desc->irq_data);
+               irq_settings_set_trigger_mask(desc, flags);
+               irqd_clear(&desc->irq_data, IRQD_LEVEL);
+               irq_settings_clr_level(desc);
+               if (flags & IRQ_TYPE_LEVEL_MASK) {
+                       irq_settings_set_level(desc);
+                       irqd_set(&desc->irq_data, IRQD_LEVEL);
+               }
+
+               ret = 0;
+               break;
+       default:
                pr_err("setting trigger mode %lu for irq %u failed (%pF)\n",
                       flags, irq, chip->irq_set_type);
-       else {
-               if (flags & (IRQ_TYPE_LEVEL_LOW | IRQ_TYPE_LEVEL_HIGH))
-                       flags |= IRQ_LEVEL;
-               /* note that IRQF_TRIGGER_MASK == IRQ_TYPE_SENSE_MASK */
-               desc->status &= ~(IRQ_LEVEL | IRQ_TYPE_SENSE_MASK);
-               desc->status |= flags;
-
-               if (chip != desc->irq_data.chip)
-                       irq_chip_set_defaults(desc->irq_data.chip);
        }
-
+       if (unmask)
+               unmask_irq(desc);
        return ret;
 }
 
@@ -624,8 +638,11 @@ static int irq_wait_for_interrupt(struct irqaction *action)
  * handler finished. unmask if the interrupt has not been disabled and
  * is marked MASKED.
  */
-static void irq_finalize_oneshot(unsigned int irq, struct irq_desc *desc)
+static void irq_finalize_oneshot(struct irq_desc *desc,
+                                struct irqaction *action, bool force)
 {
+       if (!(desc->istate & IRQS_ONESHOT))
+               return;
 again:
        chip_bus_lock(desc);
        raw_spin_lock_irq(&desc->lock);
@@ -637,26 +654,42 @@ again:
         * The thread is faster done than the hard interrupt handler
         * on the other CPU. If we unmask the irq line then the
         * interrupt can come in again and masks the line, leaves due
-        * to IRQ_INPROGRESS and the irq line is masked forever.
+        * to IRQS_INPROGRESS and the irq line is masked forever.
+        *
+        * This also serializes the state of shared oneshot handlers
+        * versus "desc->threads_onehsot |= action->thread_mask;" in
+        * irq_wake_thread(). See the comment there which explains the
+        * serialization.
         */
-       if (unlikely(desc->status & IRQ_INPROGRESS)) {
+       if (unlikely(irqd_irq_inprogress(&desc->irq_data))) {
                raw_spin_unlock_irq(&desc->lock);
                chip_bus_sync_unlock(desc);
                cpu_relax();
                goto again;
        }
 
-       if (!(desc->status & IRQ_DISABLED) && (desc->status & IRQ_MASKED)) {
-               desc->status &= ~IRQ_MASKED;
-               desc->irq_data.chip->irq_unmask(&desc->irq_data);
-       }
+       /*
+        * Now check again, whether the thread should run. Otherwise
+        * we would clear the threads_oneshot bit of this thread which
+        * was just set.
+        */
+       if (!force && test_bit(IRQTF_RUNTHREAD, &action->thread_flags))
+               goto out_unlock;
+
+       desc->threads_oneshot &= ~action->thread_mask;
+
+       if (!desc->threads_oneshot && !irqd_irq_disabled(&desc->irq_data) &&
+           irqd_irq_masked(&desc->irq_data))
+               unmask_irq(desc);
+
+out_unlock:
        raw_spin_unlock_irq(&desc->lock);
        chip_bus_sync_unlock(desc);
 }
 
 #ifdef CONFIG_SMP
 /*
- * Check whether we need to change the affinity of the interrupt thread.
+ * Check whether we need to chasnge the affinity of the interrupt thread.
  */
 static void
 irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action)
@@ -688,6 +721,39 @@ irq_thread_check_affinity(struct irq_desc *desc, struct irqaction *action) { }
 #endif
 
 /*
+ * Interrupts which are not explicitely requested as threaded
+ * interrupts rely on the implicit bh/preempt disable of the hard irq
+ * context. So we need to disable bh here to avoid deadlocks and other
+ * side effects.
+ */
+static irqreturn_t
+irq_forced_thread_fn(struct irq_desc *desc, struct irqaction *action)
+{
+       irqreturn_t ret;
+
+       local_bh_disable();
+       ret = action->thread_fn(action->irq, action->dev_id);
+       irq_finalize_oneshot(desc, action, false);
+       local_bh_enable();
+       return ret;
+}
+
+/*
+ * Interrupts explicitely requested as threaded interupts want to be
+ * preemtible - many of them need to sleep and wait for slow busses to
+ * complete.
+ */
+static irqreturn_t irq_thread_fn(struct irq_desc *desc,
+               struct irqaction *action)
+{
+       irqreturn_t ret;
+
+       ret = action->thread_fn(action->irq, action->dev_id);
+       irq_finalize_oneshot(desc, action, false);
+       return ret;
+}
+
+/*
  * Interrupt handler thread
  */
 static int irq_thread(void *data)
@@ -697,7 +763,15 @@ static int irq_thread(void *data)
        };
        struct irqaction *action = data;
        struct irq_desc *desc = irq_to_desc(action->irq);
-       int wake, oneshot = desc->status & IRQ_ONESHOT;
+       irqreturn_t (*handler_fn)(struct irq_desc *desc,
+                       struct irqaction *action);
+       int wake;
+
+       if (force_irqthreads & test_bit(IRQTF_FORCED_THREAD,
+                                       &action->thread_flags))
+               handler_fn = irq_forced_thread_fn;
+       else
+               handler_fn = irq_thread_fn;
 
        sched_setscheduler(current, SCHED_FIFO, &param);
        current->irqaction = action;
@@ -709,23 +783,23 @@ static int irq_thread(void *data)
                atomic_inc(&desc->threads_active);
 
                raw_spin_lock_irq(&desc->lock);
-               if (unlikely(desc->status & IRQ_DISABLED)) {
+               if (unlikely(irqd_irq_disabled(&desc->irq_data))) {
                        /*
                         * CHECKME: We might need a dedicated
                         * IRQ_THREAD_PENDING flag here, which
                         * retriggers the thread in check_irq_resend()
-                        * but AFAICT IRQ_PENDING should be fine as it
+                        * but AFAICT IRQS_PENDING should be fine as it
                         * retriggers the interrupt itself --- tglx
                         */
-                       desc->status |= IRQ_PENDING;
+                       desc->istate |= IRQS_PENDING;
                        raw_spin_unlock_irq(&desc->lock);
                } else {
-                       raw_spin_unlock_irq(&desc->lock);
+                       irqreturn_t action_ret;
 
-                       action->thread_fn(action->irq, action->dev_id);
-
-                       if (oneshot)
-                               irq_finalize_oneshot(action->irq, desc);
+                       raw_spin_unlock_irq(&desc->lock);
+                       action_ret = handler_fn(desc, action);
+                       if (!noirqdebug)
+                               note_interrupt(action->irq, desc, action_ret);
                }
 
                wake = atomic_dec_and_test(&desc->threads_active);
@@ -734,6 +808,9 @@ static int irq_thread(void *data)
                        wake_up(&desc->wait_for_threads);
        }
 
+       /* Prevent a stale desc->threads_oneshot */
+       irq_finalize_oneshot(desc, action, true);
+
        /*
         * Clear irqaction. Otherwise exit_irq_thread() would make
         * fuzz about an active irq thread going into nirvana.
@@ -748,6 +825,7 @@ static int irq_thread(void *data)
 void exit_irq_thread(void)
 {
        struct task_struct *tsk = current;
+       struct irq_desc *desc;
 
        if (!tsk->irqaction)
                return;
@@ -756,6 +834,14 @@ void exit_irq_thread(void)
               "exiting task \"%s\" (%d) is an active IRQ thread (irq %d)\n",
               tsk->comm ? tsk->comm : "", tsk->pid, tsk->irqaction->irq);
 
+       desc = irq_to_desc(tsk->irqaction->irq);
+
+       /*
+        * Prevent a stale desc->threads_oneshot. Must be called
+        * before setting the IRQTF_DIED flag.
+        */
+       irq_finalize_oneshot(desc, tsk->irqaction, true);
+
        /*
         * Set the THREAD DIED flag to prevent further wakeups of the
         * soon to be gone threaded handler.
@@ -763,6 +849,22 @@ void exit_irq_thread(void)
        set_bit(IRQTF_DIED, &tsk->irqaction->flags);
 }
 
+static void irq_setup_forced_threading(struct irqaction *new)
+{
+       if (!force_irqthreads)
+               return;
+       if (new->flags & (IRQF_NO_THREAD | IRQF_PERCPU | IRQF_ONESHOT))
+               return;
+
+       new->flags |= IRQF_ONESHOT;
+
+       if (!new->thread_fn) {
+               set_bit(IRQTF_FORCED_THREAD, &new->thread_flags);
+               new->thread_fn = new->handler;
+               new->handler = irq_default_primary_handler;
+       }
+}
+
 /*
  * Internal function to register an irqaction - typically used to
  * allocate special interrupts that are part of the architecture.
@@ -772,7 +874,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 {
        struct irqaction *old, **old_ptr;
        const char *old_name = NULL;
-       unsigned long flags;
+       unsigned long flags, thread_mask = 0;
        int ret, nested, shared = 0;
        cpumask_var_t mask;
 
@@ -798,15 +900,11 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
                rand_initialize_irq(irq);
        }
 
-       /* Oneshot interrupts are not allowed with shared */
-       if ((new->flags & IRQF_ONESHOT) && (new->flags & IRQF_SHARED))
-               return -EINVAL;
-
        /*
         * Check whether the interrupt nests into another interrupt
         * thread.
         */
-       nested = desc->status & IRQ_NESTED_THREAD;
+       nested = irq_settings_is_nested_thread(desc);
        if (nested) {
                if (!new->thread_fn)
                        return -EINVAL;
@@ -816,6 +914,9 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
                 * dummy function which warns when called.
                 */
                new->handler = irq_nested_primary_handler;
+       } else {
+               if (irq_settings_can_thread(desc))
+                       irq_setup_forced_threading(new);
        }
 
        /*
@@ -855,32 +956,41 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
                 * Can't share interrupts unless both agree to and are
                 * the same type (level, edge, polarity). So both flag
                 * fields must have IRQF_SHARED set and the bits which
-                * set the trigger type must match.
+                * set the trigger type must match. Also all must
+                * agree on ONESHOT.
                 */
                if (!((old->flags & new->flags) & IRQF_SHARED) ||
-                   ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK)) {
+                   ((old->flags ^ new->flags) & IRQF_TRIGGER_MASK) ||
+                   ((old->flags ^ new->flags) & IRQF_ONESHOT)) {
                        old_name = old->name;
                        goto mismatch;
                }
 
-#if defined(CONFIG_IRQ_PER_CPU)
                /* All handlers must agree on per-cpuness */
                if ((old->flags & IRQF_PERCPU) !=
                    (new->flags & IRQF_PERCPU))
                        goto mismatch;
-#endif
 
                /* add new interrupt at end of irq queue */
                do {
+                       thread_mask |= old->thread_mask;
                        old_ptr = &old->next;
                        old = *old_ptr;
                } while (old);
                shared = 1;
        }
 
-       if (!shared) {
-               irq_chip_set_defaults(desc->irq_data.chip);
+       /*
+        * Setup the thread mask for this irqaction. Unlikely to have
+        * 32 resp 64 irqs sharing one line, but who knows.
+        */
+       if (new->flags & IRQF_ONESHOT && thread_mask == ~0UL) {
+               ret = -EBUSY;
+               goto out_mask;
+       }
+       new->thread_mask = 1 << ffz(thread_mask);
 
+       if (!shared) {
                init_waitqueue_head(&desc->wait_for_threads);
 
                /* Setup the type (level, edge polarity) if configured: */
@@ -890,39 +1000,43 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 
                        if (ret)
                                goto out_mask;
-               } else
-                       compat_irq_chip_set_default_handler(desc);
-#if defined(CONFIG_IRQ_PER_CPU)
-               if (new->flags & IRQF_PERCPU)
-                       desc->status |= IRQ_PER_CPU;
-#endif
+               }
 
-               desc->status &= ~(IRQ_AUTODETECT | IRQ_WAITING | IRQ_ONESHOT |
-                                 IRQ_INPROGRESS | IRQ_SPURIOUS_DISABLED);
+               desc->istate &= ~(IRQS_AUTODETECT | IRQS_SPURIOUS_DISABLED | \
+                                 IRQS_ONESHOT | IRQS_WAITING);
+               irqd_clear(&desc->irq_data, IRQD_IRQ_INPROGRESS);
+
+               if (new->flags & IRQF_PERCPU) {
+                       irqd_set(&desc->irq_data, IRQD_PER_CPU);
+                       irq_settings_set_per_cpu(desc);
+               }
 
                if (new->flags & IRQF_ONESHOT)
-                       desc->status |= IRQ_ONESHOT;
+                       desc->istate |= IRQS_ONESHOT;
 
-               if (!(desc->status & IRQ_NOAUTOEN))
+               if (irq_settings_can_autoenable(desc))
                        irq_startup(desc);
                else
                        /* Undo nested disables: */
                        desc->depth = 1;
 
                /* Exclude IRQ from balancing if requested */
-               if (new->flags & IRQF_NOBALANCING)
-                       desc->status |= IRQ_NO_BALANCING;
+               if (new->flags & IRQF_NOBALANCING) {
+                       irq_settings_set_no_balancing(desc);
+                       irqd_set(&desc->irq_data, IRQD_NO_BALANCING);
+               }
 
                /* Set default affinity mask once everything is setup */
                setup_affinity(irq, desc, mask);
 
-       } else if ((new->flags & IRQF_TRIGGER_MASK)
-                       && (new->flags & IRQF_TRIGGER_MASK)
-                               != (desc->status & IRQ_TYPE_SENSE_MASK)) {
-               /* hope the handler works with the actual trigger mode... */
-               pr_warning("IRQ %d uses trigger mode %d; requested %d\n",
-                               irq, (int)(desc->status & IRQ_TYPE_SENSE_MASK),
-                               (int)(new->flags & IRQF_TRIGGER_MASK));
+       } else if (new->flags & IRQF_TRIGGER_MASK) {
+               unsigned int nmsk = new->flags & IRQF_TRIGGER_MASK;
+               unsigned int omsk = irq_settings_get_trigger_mask(desc);
+
+               if (nmsk != omsk)
+                       /* hope the handler works with current  trigger mode */
+                       pr_warning("IRQ %d uses trigger mode %u; requested %u\n",
+                                  irq, nmsk, omsk);
        }
 
        new->irq = irq;
@@ -936,8 +1050,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
         * Check whether we disabled the irq via the spurious handler
         * before. Reenable it and give it another chance.
         */
-       if (shared && (desc->status & IRQ_SPURIOUS_DISABLED)) {
-               desc->status &= ~IRQ_SPURIOUS_DISABLED;
+       if (shared && (desc->istate & IRQS_SPURIOUS_DISABLED)) {
+               desc->istate &= ~IRQS_SPURIOUS_DISABLED;
                __enable_irq(desc, irq, false);
        }
 
@@ -953,6 +1067,7 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
        register_irq_proc(irq, desc);
        new->dir = NULL;
        register_handler_proc(irq, new);
+       free_cpumask_var(mask);
 
        return 0;
 
@@ -968,10 +1083,10 @@ mismatch:
        ret = -EBUSY;
 
 out_mask:
+       raw_spin_unlock_irqrestore(&desc->lock, flags);
        free_cpumask_var(mask);
 
 out_thread:
-       raw_spin_unlock_irqrestore(&desc->lock, flags);
        if (new->thread) {
                struct task_struct *t = new->thread;
 
@@ -1200,7 +1315,7 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
        if (!desc)
                return -EINVAL;
 
-       if (desc->status & IRQ_NOREQUEST)
+       if (!irq_settings_can_request(desc))
                return -EINVAL;
 
        if (!handler) {
@@ -1275,7 +1390,7 @@ int request_any_context_irq(unsigned int irq, irq_handler_t handler,
        if (!desc)
                return -EINVAL;
 
-       if (desc->status & IRQ_NESTED_THREAD) {
+       if (irq_settings_is_nested_thread(desc)) {
                ret = request_threaded_irq(irq, NULL, handler,
                                           flags, name, dev_id);
                return !ret ? IRQC_IS_NESTED : ret;