Merge branch 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip

Pull irq fixes from Thomas Gleixner:

 - A few fixes mopping up the fallout of the big irq overhaul

 - Move the interrupt resource management logic out of the spin locked,
   irq disabled region to avoid unnecessary restrictions of the resource
   callbacks

 - Preparation for reworking the per cpu irq request function.

* 'irq-urgent-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip:
  irqdomain: Allow ACPI device nodes to be used as irqdomain identifiers
  genirq/debugfs: Remove redundant NULL pointer check
  genirq: Allow to pass the IRQF_TIMER flag with percpu irq request
  genirq/timings: Move free timings out of spinlocked region
  genirq: Move irq resource handling out of spinlocked region
  genirq: Add mutex to irq desc to serialize request/free_irq()
  genirq: Move bus locking into __setup_irq()
  genirq: Force inlining of __irq_startup_managed to prevent build failure
  genirq/debugfs: Fix build for !CONFIG_IRQ_DOMAIN

include/linux/interrupt.h

@@ -152,8 +152,17 @@ request_any_context_irq(unsigned int irq, irq_handler_t handler,
 			unsigned long flags, const char *name, void *dev_id);
 
 extern int __must_check
+__request_percpu_irq(unsigned int irq, irq_handler_t handler,
+		     unsigned long flags, const char *devname,
+		     void __percpu *percpu_dev_id);
+
+static inline int __must_check
 request_percpu_irq(unsigned int irq, irq_handler_t handler,
-		   const char *devname, void __percpu *percpu_dev_id);
+		   const char *devname, void __percpu *percpu_dev_id)
+{
+	return __request_percpu_irq(irq, handler, 0,
+				    devname, percpu_dev_id);
+}
 
 extern const void *free_irq(unsigned int, void *);
 extern void free_percpu_irq(unsigned int, void __percpu *);

include/linux/irqdesc.h

@@ -3,6 +3,7 @@
 
 #include <linux/rcupdate.h>
 #include <linux/kobject.h>
+#include <linux/mutex.h>
 
 /*
  * Core internal functions to deal with irq descriptors
@@ -45,6 +46,7 @@ struct pt_regs;
  *			IRQF_FORCE_RESUME set
  * @rcu:		rcu head for delayed free
  * @kobj:		kobject used to represent this struct in sysfs
+ * @request_mutex:	mutex to protect request/free before locking desc->lock
  * @dir:		/proc/irq/ procfs entry
  * @debugfs_file:	dentry for the debugfs file
  * @name:		flow handler name for /proc/interrupts output
@@ -96,6 +98,7 @@ struct irq_desc {
 	struct rcu_head		rcu;
 	struct kobject		kobj;
 #endif
+	struct mutex		request_mutex;
 	int			parent_irq;
 	struct module		*owner;
 	const char		*name;

kernel/irq/chip.c

@@ -234,7 +234,7 @@ __irq_startup_managed(struct irq_desc *desc, struct cpumask *aff, bool force)
 	return IRQ_STARTUP_MANAGED;
 }
 #else
-static int
+static __always_inline int
 __irq_startup_managed(struct irq_desc *desc, struct cpumask *aff, bool force)
 {
 	return IRQ_STARTUP_NORMAL;

kernel/irq/internals.h

@@ -437,7 +437,9 @@ static inline void irq_remove_debugfs_entry(struct irq_desc *desc)
 # ifdef CONFIG_IRQ_DOMAIN
 void irq_domain_debugfs_init(struct dentry *root);
 # else
-static inline void irq_domain_debugfs_init(struct dentry *root);
+static inline void irq_domain_debugfs_init(struct dentry *root)
+{
+}
 # endif
 #else /* CONFIG_GENERIC_IRQ_DEBUGFS */
 static inline void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *d)

kernel/irq/irqdesc.c

@@ -373,6 +373,7 @@ static struct irq_desc *alloc_desc(int irq, int node, unsigned int flags,
 
 	raw_spin_lock_init(&desc->lock);
 	lockdep_set_class(&desc->lock, &irq_desc_lock_class);
+	mutex_init(&desc->request_mutex);
 	init_rcu_head(&desc->rcu);
 
 	desc_set_defaults(irq, desc, node, affinity, owner);

kernel/irq/irqdomain.c

 #define pr_fmt(fmt)  "irq: " fmt
 
+#include <linux/acpi.h>
 #include <linux/debugfs.h>
 #include <linux/hardirq.h>
 #include <linux/interrupt.h>
@@ -155,6 +156,21 @@ struct irq_domain *__irq_domain_add(struct fwnode_handle *fwnode, int size,
 			domain->name = fwid->name;
 			break;
 		}
+#ifdef CONFIG_ACPI
+	} else if (is_acpi_device_node(fwnode)) {
+		struct acpi_buffer buf = {
+			.length = ACPI_ALLOCATE_BUFFER,
+		};
+		acpi_handle handle;
+
+		handle = acpi_device_handle(to_acpi_device_node(fwnode));
+		if (acpi_get_name(handle, ACPI_FULL_PATHNAME, &buf) == AE_OK) {
+			domain->name = buf.pointer;
+			domain->flags |= IRQ_DOMAIN_NAME_ALLOCATED;
+		}
+
+		domain->fwnode = fwnode;
+#endif
 	} else if (of_node) {
 		char *name;
 
@@ -1667,7 +1683,6 @@ static void debugfs_add_domain_dir(struct irq_domain *d)
 
 static void debugfs_remove_domain_dir(struct irq_domain *d)
 {
-	if (d->debugfs_file)
 	debugfs_remove(d->debugfs_file);
 }
 

kernel/irq/manage.c

@@ -1167,6 +1167,18 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 	if (desc->irq_data.chip->flags & IRQCHIP_ONESHOT_SAFE)
 		new->flags &= ~IRQF_ONESHOT;
 
+	mutex_lock(&desc->request_mutex);
+	if (!desc->action) {
+		ret = irq_request_resources(desc);
+		if (ret) {
+			pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
+			       new->name, irq, desc->irq_data.chip->name);
+			goto out_mutex;
+		}
+	}
+
+	chip_bus_lock(desc);
+
 	/*
 	 * The following block of code has to be executed atomically
 	 */
@@ -1267,13 +1279,6 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 	}
 
 	if (!shared) {
-		ret = irq_request_resources(desc);
-		if (ret) {
-			pr_err("Failed to request resources for %s (irq %d) on irqchip %s\n",
-			       new->name, irq, desc->irq_data.chip->name);
-			goto out_unlock;
-		}
-
 		init_waitqueue_head(&desc->wait_for_threads);
 
 		/* Setup the type (level, edge polarity) if configured: */
@@ -1347,6 +1352,8 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 	}
 
 	raw_spin_unlock_irqrestore(&desc->lock, flags);
+	chip_bus_sync_unlock(desc);
+	mutex_unlock(&desc->request_mutex);
 
 	irq_setup_timings(desc, new);
 
@@ -1378,6 +1385,14 @@ __setup_irq(unsigned int irq, struct irq_desc *desc, struct irqaction *new)
 out_unlock:
 	raw_spin_unlock_irqrestore(&desc->lock, flags);
 
+	chip_bus_sync_unlock(desc);
+
+	if (!desc->action)
+		irq_release_resources(desc);
+
+out_mutex:
+	mutex_unlock(&desc->request_mutex);
+
 out_thread:
 	if (new->thread) {
 		struct task_struct *t = new->thread;
@@ -1417,9 +1432,7 @@ int setup_irq(unsigned int irq, struct irqaction *act)
 	if (retval < 0)
 		return retval;
 
-	chip_bus_lock(desc);
 	retval = __setup_irq(irq, desc, act);
-	chip_bus_sync_unlock(desc);
 
 	if (retval)
 		irq_chip_pm_put(&desc->irq_data);
@@ -1443,6 +1456,7 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
 	if (!desc)
 		return NULL;
 
+	mutex_lock(&desc->request_mutex);
 	chip_bus_lock(desc);
 	raw_spin_lock_irqsave(&desc->lock, flags);
 
@@ -1475,8 +1489,6 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
 	if (!desc->action) {
 		irq_settings_clr_disable_unlazy(desc);
 		irq_shutdown(desc);
-		irq_release_resources(desc);
-		irq_remove_timings(desc);
 	}
 
 #ifdef CONFIG_SMP
@@ -1518,6 +1530,13 @@ static struct irqaction *__free_irq(unsigned int irq, void *dev_id)
 		}
 	}
 
+	if (!desc->action) {
+		irq_release_resources(desc);
+		irq_remove_timings(desc);
+	}
+
+	mutex_unlock(&desc->request_mutex);
+
 	irq_chip_pm_put(&desc->irq_data);
 	module_put(desc->owner);
 	kfree(action->secondary);
@@ -1674,9 +1693,7 @@ int request_threaded_irq(unsigned int irq, irq_handler_t handler,
 		return retval;
 	}
 
-	chip_bus_lock(desc);
 	retval = __setup_irq(irq, desc, action);
-	chip_bus_sync_unlock(desc);
 
 	if (retval) {
 		irq_chip_pm_put(&desc->irq_data);
@@ -1924,9 +1941,7 @@ int setup_percpu_irq(unsigned int irq, struct irqaction *act)
 	if (retval < 0)
 		return retval;
 
-	chip_bus_lock(desc);
 	retval = __setup_irq(irq, desc, act);
-	chip_bus_sync_unlock(desc);
 
 	if (retval)
 		irq_chip_pm_put(&desc->irq_data);
@@ -1935,9 +1950,10 @@ int setup_percpu_irq(unsigned int irq, struct irqaction *act)
 }
 
 /**
- *	request_percpu_irq - allocate a percpu interrupt line
+ *	__request_percpu_irq - allocate a percpu interrupt line
  *	@irq: Interrupt line to allocate
  *	@handler: Function to be called when the IRQ occurs.
+ *	@flags: Interrupt type flags (IRQF_TIMER only)
  *	@devname: An ascii name for the claiming device
  *	@dev_id: A percpu cookie passed back to the handler function
  *
@@ -1950,8 +1966,9 @@ int setup_percpu_irq(unsigned int irq, struct irqaction *act)
  *	the handler gets called with the interrupted CPU's instance of
  *	that variable.
  */
-int request_percpu_irq(unsigned int irq, irq_handler_t handler,
-		       const char *devname, void __percpu *dev_id)
+int __request_percpu_irq(unsigned int irq, irq_handler_t handler,
+			 unsigned long flags, const char *devname,
+			 void __percpu *dev_id)
 {
 	struct irqaction *action;
 	struct irq_desc *desc;
@@ -1965,12 +1982,15 @@ int request_percpu_irq(unsigned int irq, irq_handler_t handler,
 	    !irq_settings_is_per_cpu_devid(desc))
 		return -EINVAL;
 
+	if (flags && flags != IRQF_TIMER)
+		return -EINVAL;
+
 	action = kzalloc(sizeof(struct irqaction), GFP_KERNEL);
 	if (!action)
 		return -ENOMEM;
 
 	action->handler = handler;
-	action->flags = IRQF_PERCPU | IRQF_NO_SUSPEND;
+	action->flags = flags | IRQF_PERCPU | IRQF_NO_SUSPEND;
 	action->name = devname;
 	action->percpu_dev_id = dev_id;
 
@@ -1980,9 +2000,7 @@ int request_percpu_irq(unsigned int irq, irq_handler_t handler,
 		return retval;
 	}
 
-	chip_bus_lock(desc);
 	retval = __setup_irq(irq, desc, action);
-	chip_bus_sync_unlock(desc);
 
 	if (retval) {
 		irq_chip_pm_put(&desc->irq_data);
@@ -1991,7 +2009,7 @@ int request_percpu_irq(unsigned int irq, irq_handler_t handler,
 
 	return retval;
 }
-EXPORT_SYMBOL_GPL(request_percpu_irq);
+EXPORT_SYMBOL_GPL(__request_percpu_irq);
 
 /**
  *	irq_get_irqchip_state - returns the irqchip state of a interrupt.