1 files changed, 81 insertions, 20 deletions

diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index eb6078ca60c7..3164ba7ce151 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -138,6 +138,22 @@ int irq_set_affinity(unsigned int irq, const struct cpumask *cpumask)
         return 0;
 }
 
+int irq_set_affinity_hint(unsigned int irq, const struct cpumask *m)
+{
+        struct irq_desc *desc = irq_to_desc(irq);
+        unsigned long flags;
+
+        if (!desc)
+                return -EINVAL;
+
+        raw_spin_lock_irqsave(&desc->lock, flags);
+        desc->affinity_hint = m;
+        raw_spin_unlock_irqrestore(&desc->lock, flags);
+
+        return 0;
+}
+EXPORT_SYMBOL_GPL(irq_set_affinity_hint);
+
 #ifndef CONFIG_AUTO_IRQ_AFFINITY
 /*
  * Generic version of the affinity autoselector.
@@ -382,6 +398,7 @@ int can_request_irq(unsigned int irq, unsigned long irqflags)
 {
         struct irq_desc *desc = irq_to_desc(irq);
         struct irqaction *action;
+        unsigned long flags;
 
         if (!desc)
                 return 0;
@@ -389,11 +406,14 @@ int can_request_irq(unsigned int irq, unsigned long irqflags)
         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;
 }
 
@@ -483,8 +503,26 @@ static int irq_wait_for_interrupt(struct irqaction *action)
  */
 static void irq_finalize_oneshot(unsigned int irq, struct irq_desc *desc)
 {
+again:
         chip_bus_lock(irq, desc);
         raw_spin_lock_irq(&desc->lock);
+
+        /*
+         * Implausible though it may be we need to protect us against
+         * the following scenario:
+         *
+         * 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.
+         */
+        if (unlikely(desc->status & IRQ_INPROGRESS)) {
+                raw_spin_unlock_irq(&desc->lock);
+                chip_bus_sync_unlock(irq, desc);
+                cpu_relax();
+                goto again;
+        }
+
         if (!(desc->status & IRQ_DISABLED) && (desc->status & IRQ_MASKED)) {
                 desc->status &= ~IRQ_MASKED;
                 desc->chip->unmask(irq);
@@ -884,6 +922,12 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
                         desc->chip->disable(irq);
         }
 
+#ifdef CONFIG_SMP
+        /* make sure affinity_hint is cleaned up */
+        if (WARN_ON_ONCE(desc->affinity_hint))
+                desc->affinity_hint = NULL;
+#endif
+
         raw_spin_unlock_irqrestore(&desc->lock, flags);
 
         unregister_handler_proc(irq, action);
@@ -995,7 +1039,6 @@ EXPORT_SYMBOL(free_irq);
  *      Flags:
  *
  *      IRQF_SHARED             Interrupt is shared
- *      IRQF_DISABLED   Disable local interrupts while processing
  *      IRQF_SAMPLE_RANDOM      The interrupt can be used for entropy
  *      IRQF_TRIGGER_*          Specify active edge(s) or level
  *
@@ -1009,25 +1052,6 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
         int retval;
 
         /*
-         * handle_IRQ_event() always ignores IRQF_DISABLED except for
-         * the _first_ irqaction (sigh).  That can cause oopsing, but
-         * the behavior is classified as "will not fix" so we need to
-         * start nudging drivers away from using that idiom.
-         */
-        if ((irqflags & (IRQF_SHARED|IRQF_DISABLED)) ==
-                                        (IRQF_SHARED|IRQF_DISABLED)) {
-                pr_warning(
-                  "IRQ %d/%s: IRQF_DISABLED is not guaranteed on shared IRQs\n",
-                        irq, devname);
-        }
-
-#ifdef CONFIG_LOCKDEP
-        /*
-         * Lockdep wants atomic interrupt handlers:
-         */
-        irqflags |= IRQF_DISABLED;
-#endif
-        /*
          * Sanity-check: shared interrupts must pass in a real dev-ID,
          * otherwise we'll have trouble later trying to figure out
          * which interrupt is which (messes up the interrupt freeing
@@ -1088,3 +1112,40 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
         return retval;
 }
 EXPORT_SYMBOL(request_threaded_irq);
+
+/**
+ *      request_any_context_irq - allocate an interrupt line
+ *      @irq: Interrupt line to allocate
+ *      @handler: Function to be called when the IRQ occurs.
+ *                Threaded handler for threaded interrupts.
+ *      @flags: Interrupt type flags
+ *      @name: An ascii name for the claiming device
+ *      @dev_id: A cookie passed back to the handler function
+ *
+ *      This call allocates interrupt resources and enables the
+ *      interrupt line and IRQ handling. It selects either a
+ *      hardirq or threaded handling method depending on the
+ *      context.
+ *
+ *      On failure, it returns a negative value. On success,
+ *      it returns either IRQC_IS_HARDIRQ or IRQC_IS_NESTED.
+ */
+int request_any_context_irq(unsigned int irq, irq_handler_t handler,
+                            unsigned long flags, const char *name, void *dev_id)
+{
+        struct irq_desc *desc = irq_to_desc(irq);
+        int ret;
+
+        if (!desc)
+                return -EINVAL;
+
+        if (desc->status & IRQ_NESTED_THREAD) {
+                ret = request_threaded_irq(irq, NULL, handler,
+                                           flags, name, dev_id);
+                return !ret ? IRQC_IS_NESTED : ret;
+        }
+
+        ret = request_irq(irq, handler, flags, name, dev_id);
+        return !ret ? IRQC_IS_HARDIRQ : ret;
+}
+EXPORT_SYMBOL_GPL(request_any_context_irq);