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authorLinus Torvalds <torvalds@linux-foundation.org>2017-09-04 13:08:27 -0700
committerLinus Torvalds <torvalds@linux-foundation.org>2017-09-04 13:08:27 -0700
commit93cc1228b4a60584f3dadbd84f19f365bb945acb (patch)
tree9b50949e72f6df7116727e898a137f0881cb1b43 /kernel/irq
parentdd90cccffc20a15d8e4c3ac8813f4b6a6cd4766f (diff)
parent9fbd7fd28d1a1053325967670915c12b4b246a61 (diff)
downloadlinux-93cc1228b4a60584f3dadbd84f19f365bb945acb.tar.gz
Merge branch 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip
Pull irq updates from Thomas Gleixner:
 "The interrupt subsystem delivers this time:

   - Refactoring of the GIC-V3 driver to prepare for the GIC-V4 support

   - Initial GIC-V4 support

   - Consolidation of the FSL MSI support

   - Utilize the effective affinity interface in various ARM irqchip
     drivers

   - Yet another interrupt chip driver (UniPhier AIDET)

   - Bulk conversion of the irq chip driver to use %pOF

   - The usual small fixes and improvements all over the place"

* 'irq-core-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/tip: (77 commits)
  irqchip/ls-scfg-msi: Add MSI affinity support
  irqchip/ls-scfg-msi: Add LS1043a v1.1 MSI support
  irqchip/ls-scfg-msi: Add LS1046a MSI support
  arm64: dts: ls1046a: Add MSI dts node
  arm64: dts: ls1043a: Share all MSIs
  arm: dts: ls1021a: Share all MSIs
  arm64: dts: ls1043a: Fix typo of MSI compatible string
  arm: dts: ls1021a: Fix typo of MSI compatible string
  irqchip/ls-scfg-msi: Fix typo of MSI compatible strings
  irqchip/irq-bcm7120-l2: Use correct I/O accessors for irq_fwd_mask
  irqchip/mmp: Make mmp_intc_conf const
  irqchip/gic: Make irq_chip const
  irqchip/gic-v3: Advertise GICv4 support to KVM
  irqchip/gic-v4: Enable low-level GICv4 operations
  irqchip/gic-v4: Add some basic documentation
  irqchip/gic-v4: Add VLPI configuration interface
  irqchip/gic-v4: Add VPE command interface
  irqchip/gic-v4: Add per-VM VPE domain creation
  irqchip/gic-v3-its: Set implementation defined bit to enable VLPIs
  irqchip/gic-v3-its: Allow doorbell interrupts to be injected/cleared
  ...
Diffstat (limited to 'kernel/irq')
-rw-r--r--kernel/irq/Kconfig9
-rw-r--r--kernel/irq/Makefile1
-rw-r--r--kernel/irq/chip.c109
-rw-r--r--kernel/irq/debugfs.c50
-rw-r--r--kernel/irq/internals.h2
-rw-r--r--kernel/irq/irq_sim.c164
-rw-r--r--kernel/irq/irqdomain.c230
-rw-r--r--kernel/irq/manage.c14
-rw-r--r--kernel/irq/proc.c8
9 files changed, 549 insertions, 38 deletions
diff --git a/kernel/irq/Kconfig b/kernel/irq/Kconfig
index 27c4e774071c..a117adf7084b 100644
--- a/kernel/irq/Kconfig
+++ b/kernel/irq/Kconfig
@@ -63,11 +63,20 @@ config GENERIC_IRQ_CHIP
 config IRQ_DOMAIN
 	bool
 
+# Support for simulated interrupts
+config IRQ_SIM
+	bool
+	select IRQ_WORK
+
 # Support for hierarchical irq domains
 config IRQ_DOMAIN_HIERARCHY
 	bool
 	select IRQ_DOMAIN
 
+# Support for hierarchical fasteoi+edge and fasteoi+level handlers
+config IRQ_FASTEOI_HIERARCHY_HANDLERS
+	bool
+
 # Generic IRQ IPI support
 config GENERIC_IRQ_IPI
 	bool
diff --git a/kernel/irq/Makefile b/kernel/irq/Makefile
index e4aef7351f2b..1970cafe8f2a 100644
--- a/kernel/irq/Makefile
+++ b/kernel/irq/Makefile
@@ -4,6 +4,7 @@ obj-$(CONFIG_IRQ_TIMINGS) += timings.o
 obj-$(CONFIG_GENERIC_IRQ_CHIP) += generic-chip.o
 obj-$(CONFIG_GENERIC_IRQ_PROBE) += autoprobe.o
 obj-$(CONFIG_IRQ_DOMAIN) += irqdomain.o
+obj-$(CONFIG_IRQ_SIM) += irq_sim.o
 obj-$(CONFIG_PROC_FS) += proc.o
 obj-$(CONFIG_GENERIC_PENDING_IRQ) += migration.o
 obj-$(CONFIG_GENERIC_IRQ_MIGRATION) += cpuhotplug.o
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 3675c6004f2a..f51b7b6d2451 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -1098,6 +1098,112 @@ void irq_cpu_offline(void)
 }
 
 #ifdef	CONFIG_IRQ_DOMAIN_HIERARCHY
+
+#ifdef CONFIG_IRQ_FASTEOI_HIERARCHY_HANDLERS
+/**
+ *	handle_fasteoi_ack_irq - irq handler for edge hierarchy
+ *	stacked on transparent controllers
+ *
+ *	@desc:	the interrupt description structure for this irq
+ *
+ *	Like handle_fasteoi_irq(), but for use with hierarchy where
+ *	the irq_chip also needs to have its ->irq_ack() function
+ *	called.
+ */
+void handle_fasteoi_ack_irq(struct irq_desc *desc)
+{
+	struct irq_chip *chip = desc->irq_data.chip;
+
+	raw_spin_lock(&desc->lock);
+
+	if (!irq_may_run(desc))
+		goto out;
+
+	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
+
+	/*
+	 * If its disabled or no action available
+	 * then mask it and get out of here:
+	 */
+	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
+		desc->istate |= IRQS_PENDING;
+		mask_irq(desc);
+		goto out;
+	}
+
+	kstat_incr_irqs_this_cpu(desc);
+	if (desc->istate & IRQS_ONESHOT)
+		mask_irq(desc);
+
+	/* Start handling the irq */
+	desc->irq_data.chip->irq_ack(&desc->irq_data);
+
+	preflow_handler(desc);
+	handle_irq_event(desc);
+
+	cond_unmask_eoi_irq(desc, chip);
+
+	raw_spin_unlock(&desc->lock);
+	return;
+out:
+	if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED))
+		chip->irq_eoi(&desc->irq_data);
+	raw_spin_unlock(&desc->lock);
+}
+EXPORT_SYMBOL_GPL(handle_fasteoi_ack_irq);
+
+/**
+ *	handle_fasteoi_mask_irq - irq handler for level hierarchy
+ *	stacked on transparent controllers
+ *
+ *	@desc:	the interrupt description structure for this irq
+ *
+ *	Like handle_fasteoi_irq(), but for use with hierarchy where
+ *	the irq_chip also needs to have its ->irq_mask_ack() function
+ *	called.
+ */
+void handle_fasteoi_mask_irq(struct irq_desc *desc)
+{
+	struct irq_chip *chip = desc->irq_data.chip;
+
+	raw_spin_lock(&desc->lock);
+	mask_ack_irq(desc);
+
+	if (!irq_may_run(desc))
+		goto out;
+
+	desc->istate &= ~(IRQS_REPLAY | IRQS_WAITING);
+
+	/*
+	 * If its disabled or no action available
+	 * then mask it and get out of here:
+	 */
+	if (unlikely(!desc->action || irqd_irq_disabled(&desc->irq_data))) {
+		desc->istate |= IRQS_PENDING;
+		mask_irq(desc);
+		goto out;
+	}
+
+	kstat_incr_irqs_this_cpu(desc);
+	if (desc->istate & IRQS_ONESHOT)
+		mask_irq(desc);
+
+	preflow_handler(desc);
+	handle_irq_event(desc);
+
+	cond_unmask_eoi_irq(desc, chip);
+
+	raw_spin_unlock(&desc->lock);
+	return;
+out:
+	if (!(chip->flags & IRQCHIP_EOI_IF_HANDLED))
+		chip->irq_eoi(&desc->irq_data);
+	raw_spin_unlock(&desc->lock);
+}
+EXPORT_SYMBOL_GPL(handle_fasteoi_mask_irq);
+
+#endif /* CONFIG_IRQ_FASTEOI_HIERARCHY_HANDLERS */
+
 /**
  * irq_chip_enable_parent - Enable the parent interrupt (defaults to unmask if
  * NULL)
@@ -1111,6 +1217,7 @@ void irq_chip_enable_parent(struct irq_data *data)
 	else
 		data->chip->irq_unmask(data);
 }
+EXPORT_SYMBOL_GPL(irq_chip_enable_parent);
 
 /**
  * irq_chip_disable_parent - Disable the parent interrupt (defaults to mask if
@@ -1125,6 +1232,7 @@ void irq_chip_disable_parent(struct irq_data *data)
 	else
 		data->chip->irq_mask(data);
 }
+EXPORT_SYMBOL_GPL(irq_chip_disable_parent);
 
 /**
  * irq_chip_ack_parent - Acknowledge the parent interrupt
@@ -1187,6 +1295,7 @@ int irq_chip_set_affinity_parent(struct irq_data *data,
 
 	return -ENOSYS;
 }
+EXPORT_SYMBOL_GPL(irq_chip_set_affinity_parent);
 
 /**
  * irq_chip_set_type_parent - Set IRQ type on the parent interrupt
diff --git a/kernel/irq/debugfs.c b/kernel/irq/debugfs.c
index 4d384edc0c64..c3fdb36dec30 100644
--- a/kernel/irq/debugfs.c
+++ b/kernel/irq/debugfs.c
@@ -5,6 +5,7 @@
  */
 #include <linux/irqdomain.h>
 #include <linux/irq.h>
+#include <linux/uaccess.h>
 
 #include "internals.h"
 
@@ -171,8 +172,55 @@ static int irq_debug_open(struct inode *inode, struct file *file)
 	return single_open(file, irq_debug_show, inode->i_private);
 }
 
+static ssize_t irq_debug_write(struct file *file, const char __user *user_buf,
+			       size_t count, loff_t *ppos)
+{
+	struct irq_desc *desc = file_inode(file)->i_private;
+	char buf[8] = { 0, };
+	size_t size;
+
+	size = min(sizeof(buf) - 1, count);
+	if (copy_from_user(buf, user_buf, size))
+		return -EFAULT;
+
+	if (!strncmp(buf, "trigger", size)) {
+		unsigned long flags;
+		int err;
+
+		/* Try the HW interface first */
+		err = irq_set_irqchip_state(irq_desc_get_irq(desc),
+					    IRQCHIP_STATE_PENDING, true);
+		if (!err)
+			return count;
+
+		/*
+		 * Otherwise, try to inject via the resend interface,
+		 * which may or may not succeed.
+		 */
+		chip_bus_lock(desc);
+		raw_spin_lock_irqsave(&desc->lock, flags);
+
+		if (irq_settings_is_level(desc)) {
+			/* Can't do level, sorry */
+			err = -EINVAL;
+		} else {
+			desc->istate |= IRQS_PENDING;
+			check_irq_resend(desc);
+			err = 0;
+		}
+
+		raw_spin_unlock_irqrestore(&desc->lock, flags);
+		chip_bus_sync_unlock(desc);
+
+		return err ? err : count;
+	}
+
+	return count;
+}
+
 static const struct file_operations dfs_irq_ops = {
 	.open		= irq_debug_open,
+	.write		= irq_debug_write,
 	.read		= seq_read,
 	.llseek		= seq_lseek,
 	.release	= single_release,
@@ -186,7 +234,7 @@ void irq_add_debugfs_entry(unsigned int irq, struct irq_desc *desc)
 		return;
 
 	sprintf(name, "%d", irq);
-	desc->debugfs_file = debugfs_create_file(name, 0444, irq_dir, desc,
+	desc->debugfs_file = debugfs_create_file(name, 0644, irq_dir, desc,
 						 &dfs_irq_ops);
 }
 
diff --git a/kernel/irq/internals.h b/kernel/irq/internals.h
index a2c48058354c..a4aa39009f0d 100644
--- a/kernel/irq/internals.h
+++ b/kernel/irq/internals.h
@@ -151,7 +151,7 @@ static inline void chip_bus_sync_unlock(struct irq_desc *desc)
 #define IRQ_GET_DESC_CHECK_PERCPU	(_IRQ_DESC_CHECK | _IRQ_DESC_PERCPU)
 
 #define for_each_action_of_desc(desc, act)			\
-	for (act = desc->act; act; act = act->next)
+	for (act = desc->action; act; act = act->next)
 
 struct irq_desc *
 __irq_get_desc_lock(unsigned int irq, unsigned long *flags, bool bus,
diff --git a/kernel/irq/irq_sim.c b/kernel/irq/irq_sim.c
new file mode 100644
index 000000000000..24caabf1a0f7
--- /dev/null
+++ b/kernel/irq/irq_sim.c
@@ -0,0 +1,164 @@
+/*
+ * Copyright (C) 2017 Bartosz Golaszewski <brgl@bgdev.pl>
+ *
+ * This program is free software; you can redistribute  it and/or modify it
+ * under  the terms of  the GNU General  Public License as published by the
+ * Free Software Foundation;  either version 2 of the  License, or (at your
+ * option) any later version.
+ */
+
+#include <linux/irq_sim.h>
+#include <linux/irq.h>
+
+struct irq_sim_devres {
+	struct irq_sim		*sim;
+};
+
+static void irq_sim_irqmask(struct irq_data *data)
+{
+	struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
+
+	irq_ctx->enabled = false;
+}
+
+static void irq_sim_irqunmask(struct irq_data *data)
+{
+	struct irq_sim_irq_ctx *irq_ctx = irq_data_get_irq_chip_data(data);
+
+	irq_ctx->enabled = true;
+}
+
+static struct irq_chip irq_sim_irqchip = {
+	.name		= "irq_sim",
+	.irq_mask	= irq_sim_irqmask,
+	.irq_unmask	= irq_sim_irqunmask,
+};
+
+static void irq_sim_handle_irq(struct irq_work *work)
+{
+	struct irq_sim_work_ctx *work_ctx;
+
+	work_ctx = container_of(work, struct irq_sim_work_ctx, work);
+	handle_simple_irq(irq_to_desc(work_ctx->irq));
+}
+
+/**
+ * irq_sim_init - Initialize the interrupt simulator: allocate a range of
+ *                dummy interrupts.
+ *
+ * @sim:        The interrupt simulator object to initialize.
+ * @num_irqs:   Number of interrupts to allocate
+ *
+ * Returns 0 on success and a negative error number on failure.
+ */
+int irq_sim_init(struct irq_sim *sim, unsigned int num_irqs)
+{
+	int i;
+
+	sim->irqs = kmalloc_array(num_irqs, sizeof(*sim->irqs), GFP_KERNEL);
+	if (!sim->irqs)
+		return -ENOMEM;
+
+	sim->irq_base = irq_alloc_descs(-1, 0, num_irqs, 0);
+	if (sim->irq_base < 0) {
+		kfree(sim->irqs);
+		return sim->irq_base;
+	}
+
+	for (i = 0; i < num_irqs; i++) {
+		sim->irqs[i].irqnum = sim->irq_base + i;
+		sim->irqs[i].enabled = false;
+		irq_set_chip(sim->irq_base + i, &irq_sim_irqchip);
+		irq_set_chip_data(sim->irq_base + i, &sim->irqs[i]);
+		irq_set_handler(sim->irq_base + i, &handle_simple_irq);
+		irq_modify_status(sim->irq_base + i,
+				  IRQ_NOREQUEST | IRQ_NOAUTOEN, IRQ_NOPROBE);
+	}
+
+	init_irq_work(&sim->work_ctx.work, irq_sim_handle_irq);
+	sim->irq_count = num_irqs;
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(irq_sim_init);
+
+/**
+ * irq_sim_fini - Deinitialize the interrupt simulator: free the interrupt
+ *                descriptors and allocated memory.
+ *
+ * @sim:        The interrupt simulator to tear down.
+ */
+void irq_sim_fini(struct irq_sim *sim)
+{
+	irq_work_sync(&sim->work_ctx.work);
+	irq_free_descs(sim->irq_base, sim->irq_count);
+	kfree(sim->irqs);
+}
+EXPORT_SYMBOL_GPL(irq_sim_fini);
+
+static void devm_irq_sim_release(struct device *dev, void *res)
+{
+	struct irq_sim_devres *this = res;
+
+	irq_sim_fini(this->sim);
+}
+
+/**
+ * irq_sim_init - Initialize the interrupt simulator for a managed device.
+ *
+ * @dev:        Device to initialize the simulator object for.
+ * @sim:        The interrupt simulator object to initialize.
+ * @num_irqs:   Number of interrupts to allocate
+ *
+ * Returns 0 on success and a negative error number on failure.
+ */
+int devm_irq_sim_init(struct device *dev, struct irq_sim *sim,
+		      unsigned int num_irqs)
+{
+	struct irq_sim_devres *dr;
+	int rv;
+
+	dr = devres_alloc(devm_irq_sim_release, sizeof(*dr), GFP_KERNEL);
+	if (!dr)
+		return -ENOMEM;
+
+	rv = irq_sim_init(sim, num_irqs);
+	if (rv) {
+		devres_free(dr);
+		return rv;
+	}
+
+	dr->sim = sim;
+	devres_add(dev, dr);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(devm_irq_sim_init);
+
+/**
+ * irq_sim_fire - Enqueue an interrupt.
+ *
+ * @sim:        The interrupt simulator object.
+ * @offset:     Offset of the simulated interrupt which should be fired.
+ */
+void irq_sim_fire(struct irq_sim *sim, unsigned int offset)
+{
+	if (sim->irqs[offset].enabled) {
+		sim->work_ctx.irq = irq_sim_irqnum(sim, offset);
+		irq_work_queue(&sim->work_ctx.work);
+	}
+}
+EXPORT_SYMBOL_GPL(irq_sim_fire);
+
+/**
+ * irq_sim_irqnum - Get the allocated number of a dummy interrupt.
+ *
+ * @sim:        The interrupt simulator object.
+ * @offset:     Offset of the simulated interrupt for which to retrieve
+ *              the number.
+ */
+int irq_sim_irqnum(struct irq_sim *sim, unsigned int offset)
+{
+	return sim->irqs[offset].irqnum;
+}
+EXPORT_SYMBOL_GPL(irq_sim_irqnum);
diff --git a/kernel/irq/irqdomain.c b/kernel/irq/irqdomain.c
index f1f251479aa6..d62351714f3e 100644
--- a/kernel/irq/irqdomain.c
+++ b/kernel/irq/irqdomain.c
@@ -455,6 +455,31 @@ void irq_set_default_host(struct irq_domain *domain)
 }
 EXPORT_SYMBOL_GPL(irq_set_default_host);
 
+static void irq_domain_clear_mapping(struct irq_domain *domain,
+				     irq_hw_number_t hwirq)
+{
+	if (hwirq < domain->revmap_size) {
+		domain->linear_revmap[hwirq] = 0;
+	} else {
+		mutex_lock(&revmap_trees_mutex);
+		radix_tree_delete(&domain->revmap_tree, hwirq);
+		mutex_unlock(&revmap_trees_mutex);
+	}
+}
+
+static void irq_domain_set_mapping(struct irq_domain *domain,
+				   irq_hw_number_t hwirq,
+				   struct irq_data *irq_data)
+{
+	if (hwirq < domain->revmap_size) {
+		domain->linear_revmap[hwirq] = irq_data->irq;
+	} else {
+		mutex_lock(&revmap_trees_mutex);
+		radix_tree_insert(&domain->revmap_tree, hwirq, irq_data);
+		mutex_unlock(&revmap_trees_mutex);
+	}
+}
+
 void irq_domain_disassociate(struct irq_domain *domain, unsigned int irq)
 {
 	struct irq_data *irq_data = irq_get_irq_data(irq);
@@ -483,13 +508,7 @@ void irq_domain_disassociate(struct irq_domain *domain, unsigned int irq)
 	domain->mapcount--;
 
 	/* Clear reverse map for this hwirq */
-	if (hwirq < domain->revmap_size) {
-		domain->linear_revmap[hwirq] = 0;
-	} else {
-		mutex_lock(&revmap_trees_mutex);
-		radix_tree_delete(&domain->revmap_tree, hwirq);
-		mutex_unlock(&revmap_trees_mutex);
-	}
+	irq_domain_clear_mapping(domain, hwirq);
 }
 
 int irq_domain_associate(struct irq_domain *domain, unsigned int virq,
@@ -533,13 +552,7 @@ int irq_domain_associate(struct irq_domain *domain, unsigned int virq,
 	}
 
 	domain->mapcount++;
-	if (hwirq < domain->revmap_size) {
-		domain->linear_revmap[hwirq] = virq;
-	} else {
-		mutex_lock(&revmap_trees_mutex);
-		radix_tree_insert(&domain->revmap_tree, hwirq, irq_data);
-		mutex_unlock(&revmap_trees_mutex);
-	}
+	irq_domain_set_mapping(domain, hwirq, irq_data);
 	mutex_unlock(&irq_domain_mutex);
 
 	irq_clear_status_flags(virq, IRQ_NOREQUEST);
@@ -1138,16 +1151,9 @@ static void irq_domain_insert_irq(int virq)
 
 	for (data = irq_get_irq_data(virq); data; data = data->parent_data) {
 		struct irq_domain *domain = data->domain;
-		irq_hw_number_t hwirq = data->hwirq;
 
 		domain->mapcount++;
-		if (hwirq < domain->revmap_size) {
-			domain->linear_revmap[hwirq] = virq;
-		} else {
-			mutex_lock(&revmap_trees_mutex);
-			radix_tree_insert(&domain->revmap_tree, hwirq, data);
-			mutex_unlock(&revmap_trees_mutex);
-		}
+		irq_domain_set_mapping(domain, data->hwirq, data);
 
 		/* If not already assigned, give the domain the chip's name */
 		if (!domain->name && data->chip)
@@ -1171,13 +1177,7 @@ static void irq_domain_remove_irq(int virq)
 		irq_hw_number_t hwirq = data->hwirq;
 
 		domain->mapcount--;
-		if (hwirq < domain->revmap_size) {
-			domain->linear_revmap[hwirq] = 0;
-		} else {
-			mutex_lock(&revmap_trees_mutex);
-			radix_tree_delete(&domain->revmap_tree, hwirq);
-			mutex_unlock(&revmap_trees_mutex);
-		}
+		irq_domain_clear_mapping(domain, hwirq);
 	}
 }
 
@@ -1362,7 +1362,8 @@ static void irq_domain_free_irqs_hierarchy(struct irq_domain *domain,
 					   unsigned int irq_base,
 					   unsigned int nr_irqs)
 {
-	domain->ops->free(domain, irq_base, nr_irqs);
+	if (domain->ops->free)
+		domain->ops->free(domain, irq_base, nr_irqs);
 }
 
 int irq_domain_alloc_irqs_hierarchy(struct irq_domain *domain,
@@ -1448,6 +1449,175 @@ out_free_desc:
 	return ret;
 }
 
+/* The irq_data was moved, fix the revmap to refer to the new location */
+static void irq_domain_fix_revmap(struct irq_data *d)
+{
+	void **slot;
+
+	if (d->hwirq < d->domain->revmap_size)
+		return; /* Not using radix tree. */
+
+	/* Fix up the revmap. */
+	mutex_lock(&revmap_trees_mutex);
+	slot = radix_tree_lookup_slot(&d->domain->revmap_tree, d->hwirq);
+	if (slot)
+		radix_tree_replace_slot(&d->domain->revmap_tree, slot, d);
+	mutex_unlock(&revmap_trees_mutex);
+}
+
+/**
+ * irq_domain_push_irq() - Push a domain in to the top of a hierarchy.
+ * @domain:	Domain to push.
+ * @virq:	Irq to push the domain in to.
+ * @arg:	Passed to the irq_domain_ops alloc() function.
+ *
+ * For an already existing irqdomain hierarchy, as might be obtained
+ * via a call to pci_enable_msix(), add an additional domain to the
+ * head of the processing chain.  Must be called before request_irq()
+ * has been called.
+ */
+int irq_domain_push_irq(struct irq_domain *domain, int virq, void *arg)
+{
+	struct irq_data *child_irq_data;
+	struct irq_data *root_irq_data = irq_get_irq_data(virq);
+	struct irq_desc *desc;
+	int rv = 0;
+
+	/*
+	 * Check that no action has been set, which indicates the virq
+	 * is in a state where this function doesn't have to deal with
+	 * races between interrupt handling and maintaining the
+	 * hierarchy.  This will catch gross misuse.  Attempting to
+	 * make the check race free would require holding locks across
+	 * calls to struct irq_domain_ops->alloc(), which could lead
+	 * to deadlock, so we just do a simple check before starting.
+	 */
+	desc = irq_to_desc(virq);
+	if (!desc)
+		return -EINVAL;
+	if (WARN_ON(desc->action))
+		return -EBUSY;
+
+	if (domain == NULL)
+		return -EINVAL;
+
+	if (WARN_ON(!irq_domain_is_hierarchy(domain)))
+		return -EINVAL;
+
+	if (!root_irq_data)
+		return -EINVAL;
+
+	if (domain->parent != root_irq_data->domain)
+		return -EINVAL;
+
+	child_irq_data = kzalloc_node(sizeof(*child_irq_data), GFP_KERNEL,
+				      irq_data_get_node(root_irq_data));
+	if (!child_irq_data)
+		return -ENOMEM;
+
+	mutex_lock(&irq_domain_mutex);
+
+	/* Copy the original irq_data. */
+	*child_irq_data = *root_irq_data;
+
+	/*
+	 * Overwrite the root_irq_data, which is embedded in struct
+	 * irq_desc, with values for this domain.
+	 */
+	root_irq_data->parent_data = child_irq_data;
+	root_irq_data->domain = domain;
+	root_irq_data->mask = 0;
+	root_irq_data->hwirq = 0;
+	root_irq_data->chip = NULL;
+	root_irq_data->chip_data = NULL;
+
+	/* May (probably does) set hwirq, chip, etc. */
+	rv = irq_domain_alloc_irqs_hierarchy(domain, virq, 1, arg);
+	if (rv) {
+		/* Restore the original irq_data. */
+		*root_irq_data = *child_irq_data;
+		goto error;
+	}
+
+	irq_domain_fix_revmap(child_irq_data);
+	irq_domain_set_mapping(domain, root_irq_data->hwirq, root_irq_data);
+
+error:
+	mutex_unlock(&irq_domain_mutex);
+
+	return rv;
+}
+EXPORT_SYMBOL_GPL(irq_domain_push_irq);
+
+/**
+ * irq_domain_pop_irq() - Remove a domain from the top of a hierarchy.
+ * @domain:	Domain to remove.
+ * @virq:	Irq to remove the domain from.
+ *
+ * Undo the effects of a call to irq_domain_push_irq().  Must be
+ * called either before request_irq() or after free_irq().
+ */
+int irq_domain_pop_irq(struct irq_domain *domain, int virq)
+{
+	struct irq_data *root_irq_data = irq_get_irq_data(virq);
+	struct irq_data *child_irq_data;
+	struct irq_data *tmp_irq_data;
+	struct irq_desc *desc;
+
+	/*
+	 * Check that no action is set, which indicates the virq is in
+	 * a state where this function doesn't have to deal with races
+	 * between interrupt handling and maintaining the hierarchy.
+	 * This will catch gross misuse.  Attempting to make the check
+	 * race free would require holding locks across calls to
+	 * struct irq_domain_ops->free(), which could lead to
+	 * deadlock, so we just do a simple check before starting.
+	 */
+	desc = irq_to_desc(virq);
+	if (!desc)
+		return -EINVAL;
+	if (WARN_ON(desc->action))
+		return -EBUSY;
+
+	if (domain == NULL)
+		return -EINVAL;
+
+	if (!root_irq_data)
+		return -EINVAL;
+
+	tmp_irq_data = irq_domain_get_irq_data(domain, virq);
+
+	/* We can only "pop" if this domain is at the top of the list */
+	if (WARN_ON(root_irq_data != tmp_irq_data))
+		return -EINVAL;
+
+	if (WARN_ON(root_irq_data->domain != domain))
+		return -EINVAL;
+
+	child_irq_data = root_irq_data->parent_data;
+	if (WARN_ON(!child_irq_data))
+		return -EINVAL;
+
+	mutex_lock(&irq_domain_mutex);
+
+	root_irq_data->parent_data = NULL;
+
+	irq_domain_clear_mapping(domain, root_irq_data->hwirq);
+	irq_domain_free_irqs_hierarchy(domain, virq, 1);
+
+	/* Restore the original irq_data. */
+	*root_irq_data = *child_irq_data;
+
+	irq_domain_fix_revmap(root_irq_data);
+
+	mutex_unlock(&irq_domain_mutex);
+
+	kfree(child_irq_data);
+
+	return 0;
+}
+EXPORT_SYMBOL_GPL(irq_domain_pop_irq);
+
 /**
  * irq_domain_free_irqs - Free IRQ number and associated data structures
  * @virq:	base IRQ number
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 1d1a5b945ab4..573dc52b0806 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -400,8 +400,18 @@ int irq_set_vcpu_affinity(unsigned int irq, void *vcpu_info)
 		return -EINVAL;
 
 	data = irq_desc_get_irq_data(desc);
-	chip = irq_data_get_irq_chip(data);
-	if (chip && chip->irq_set_vcpu_affinity)
+	do {
+		chip = irq_data_get_irq_chip(data);
+		if (chip && chip->irq_set_vcpu_affinity)
+			break;
+#ifdef CONFIG_IRQ_DOMAIN_HIERARCHY
+		data = data->parent_data;
+#else
+		data = NULL;
+#endif
+	} while (data);
+
+	if (data)
 		ret = chip->irq_set_vcpu_affinity(data, vcpu_info);
 	irq_put_desc_unlock(desc, flags);
 
diff --git a/kernel/irq/proc.c b/kernel/irq/proc.c
index 7f9642a1e267..6376b4a598d3 100644
--- a/kernel/irq/proc.c
+++ b/kernel/irq/proc.c
@@ -61,12 +61,12 @@ static int show_irq_affinity(int type, struct seq_file *m)
 	case EFFECTIVE:
 	case EFFECTIVE_LIST:
 #ifdef CONFIG_GENERIC_IRQ_EFFECTIVE_AFF_MASK
-		mask = desc->irq_common_data.effective_affinity;
+		mask = irq_data_get_effective_affinity_mask(&desc->irq_data);
 		break;
-#else
-		return -EINVAL;
 #endif
-	};
+	default:
+		return -EINVAL;
+	}
 
 	switch (type) {
 	case AFFINITY_LIST: