Merge branch 'genirq-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip

This merges branches irq/genirq, irq/sparseirq-v4, timers/hpet-percpu
and x86/uv.

The sparseirq branch is just preliminary groundwork: no sparse IRQs are
actually implemented by this tree anymore - just the new APIs are added
while keeping the old way intact as well (the new APIs map 1:1 to
irq_desc[]).  The 'real' sparse IRQ support will then be a relatively
small patch ontop of this - with a v2.6.29 merge target.

* 'genirq-v28-for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/tip/linux-2.6-tip: (178 commits)
  genirq: improve include files
  intr_remapping: fix typo
  io_apic: make irq_mis_count available on 64-bit too
  genirq: fix name space collisions of nr_irqs in arch/*
  genirq: fix name space collision of nr_irqs in autoprobe.c
  genirq: use iterators for irq_desc loops
  proc: fixup irq iterator
  genirq: add reverse iterator for irq_desc
  x86: move ack_bad_irq() to irq.c
  x86: unify show_interrupts() and proc helpers
  x86: cleanup show_interrupts
  genirq: cleanup the sparseirq modifications
  genirq: remove artifacts from sparseirq removal
  genirq: revert dynarray
  genirq: remove irq_to_desc_alloc
  genirq: remove sparse irq code
  genirq: use inline function for irq_to_desc
  genirq: consolidate nr_irqs and for_each_irq_desc()
  x86: remove sparse irq from Kconfig
  genirq: define nr_irqs for architectures with GENERIC_HARDIRQS=n
  ...

35 files changed, 283 insertions, 154 deletions

diff --git a/drivers/char/hpet.c b/drivers/char/hpet.c
index f3cfb4c7612..408f5f92cb4 100644
--- a/drivers/char/hpet.c
+++ b/drivers/char/hpet.c
@@ -219,7 +219,7 @@ static void hpet_timer_set_irq(struct hpet_dev *devp)
 	for (irq = find_first_bit(&v, HPET_MAX_IRQ); irq < HPET_MAX_IRQ;
 		irq = find_next_bit(&v, HPET_MAX_IRQ, 1 + irq)) {
 
-		if (irq >= NR_IRQS) {
+		if (irq >= nr_irqs) {
 			irq = HPET_MAX_IRQ;
 			break;
 		}
diff --git a/drivers/char/random.c b/drivers/char/random.c
index c8752eaad48..705a839f179 100644
--- a/drivers/char/random.c
+++ b/drivers/char/random.c
@@ -558,9 +558,26 @@ struct timer_rand_state {
 	unsigned dont_count_entropy:1;
 };
 
-static struct timer_rand_state input_timer_state;
 static struct timer_rand_state *irq_timer_state[NR_IRQS];
 
+static struct timer_rand_state *get_timer_rand_state(unsigned int irq)
+{
+	if (irq >= nr_irqs)
+		return NULL;
+
+	return irq_timer_state[irq];
+}
+
+static void set_timer_rand_state(unsigned int irq, struct timer_rand_state *state)
+{
+	if (irq >= nr_irqs)
+		return;
+
+	irq_timer_state[irq] = state;
+}
+
+static struct timer_rand_state input_timer_state;
+
 /*
  * This function adds entropy to the entropy "pool" by using timing
  * delays.  It uses the timer_rand_state structure to make an estimate
@@ -648,11 +665,15 @@ EXPORT_SYMBOL_GPL(add_input_randomness);
 
 void add_interrupt_randomness(int irq)
 {
-	if (irq >= NR_IRQS || irq_timer_state[irq] == NULL)
+	struct timer_rand_state *state;
+
+	state = get_timer_rand_state(irq);
+
+	if (state == NULL)
 		return;
 
 	DEBUG_ENT("irq event %d\n", irq);
-	add_timer_randomness(irq_timer_state[irq], 0x100 + irq);
+	add_timer_randomness(state, 0x100 + irq);
 }
 
 #ifdef CONFIG_BLOCK
@@ -912,7 +933,12 @@ void rand_initialize_irq(int irq)
 {
 	struct timer_rand_state *state;
 
-	if (irq >= NR_IRQS || irq_timer_state[irq])
+	if (irq >= nr_irqs)
+		return;
+
+	state = get_timer_rand_state(irq);
+
+	if (state)
 		return;
 
 	/*
@@ -921,7 +947,7 @@ void rand_initialize_irq(int irq)
 	 */
 	state = kzalloc(sizeof(struct timer_rand_state), GFP_KERNEL);
 	if (state)
-		irq_timer_state[irq] = state;
+		set_timer_rand_state(irq, state);
 }
 
 #ifdef CONFIG_BLOCK
diff --git a/drivers/char/vr41xx_giu.c b/drivers/char/vr41xx_giu.c
index ffe9b4e3072..54c837288d1 100644
--- a/drivers/char/vr41xx_giu.c
+++ b/drivers/char/vr41xx_giu.c
@@ -641,7 +641,7 @@ static int __devinit giu_probe(struct platform_device *dev)
 	}
 
 	irq = platform_get_irq(dev, 0);
-	if (irq < 0 || irq >= NR_IRQS)
+	if (irq < 0 || irq >= nr_irqs)
 		return -EBUSY;
 
 	return cascade_irq(irq, giu_get_irq);
diff --git a/drivers/gpio/gpiolib.c b/drivers/gpio/gpiolib.c
index 22edc4273ef..faa1cc66e9c 100644
--- a/drivers/gpio/gpiolib.c
+++ b/drivers/gpio/gpiolib.c
@@ -1143,7 +1143,7 @@ static void gpiolib_dbg_show(struct seq_file *s, struct gpio_chip *chip)
 
 		if (!is_out) {
 			int		irq = gpio_to_irq(gpio);
-			struct irq_desc	*desc = irq_desc + irq;
+			struct irq_desc	*desc = irq_to_desc(irq);
 
 			/* This races with request_irq(), set_irq_type(),
 			 * and set_irq_wake() ... but those are "rare".
diff --git a/drivers/mfd/asic3.c b/drivers/mfd/asic3.c
index ba5aa200827..e4c0db4dc7b 100644
--- a/drivers/mfd/asic3.c
+++ b/drivers/mfd/asic3.c
@@ -123,7 +123,7 @@ static void asic3_irq_demux(unsigned int irq, struct irq_desc *desc)
 					irqnr = asic->irq_base +
 						(ASIC3_GPIOS_PER_BANK * bank)
 						+ i;
-					desc = irq_desc + irqnr;
+					desc = irq_to_desc(irqnr);
 					desc->handle_irq(irqnr, desc);
 					if (asic->irq_bothedge[bank] & bit)
 						asic3_irq_flip_edge(asic, base,
@@ -136,7 +136,7 @@ static void asic3_irq_demux(unsigned int irq, struct irq_desc *desc)
 		for (i = ASIC3_NUM_GPIOS; i < ASIC3_NR_IRQS; i++) {
 			/* They start at bit 4 and go up */
 			if (status & (1 << (i - ASIC3_NUM_GPIOS + 4))) {
-				desc = irq_desc + asic->irq_base + i;
+				desc = irq_to_desc(asic->irq_base + i);
 				desc->handle_irq(asic->irq_base + i,
 						 desc);
 			}
diff --git a/drivers/mfd/htc-egpio.c b/drivers/mfd/htc-egpio.c
index 50dff6e0088..1a4d04664d6 100644
--- a/drivers/mfd/htc-egpio.c
+++ b/drivers/mfd/htc-egpio.c
@@ -112,7 +112,7 @@ static void egpio_handler(unsigned int irq, struct irq_desc *desc)
 		/* Run irq handler */
 		pr_debug("got IRQ %d\n", irqpin);
 		irq = ei->irq_start + irqpin;
-		desc = &irq_desc[irq];
+		desc = irq_to_desc(irq);
 		desc->handle_irq(irq, desc);
 	}
 }
diff --git a/drivers/net/3c59x.c b/drivers/net/3c59x.c
index 491ee16da5c..9ba295d9dd9 100644
--- a/drivers/net/3c59x.c
+++ b/drivers/net/3c59x.c
@@ -90,7 +90,7 @@ static int vortex_debug = 1;
 #include <linux/eisa.h>
 #include <linux/bitops.h>
 #include <linux/jiffies.h>
-#include <asm/irq.h>			/* For NR_IRQS only. */
+#include <asm/irq.h>			/* For nr_irqs only. */
 #include <asm/io.h>
 #include <asm/uaccess.h>
 
@@ -1221,7 +1221,7 @@ static int __devinit vortex_probe1(struct device *gendev,
 	if (print_info)
 		printk(", IRQ %d\n", dev->irq);
 	/* Tell them about an invalid IRQ. */
-	if (dev->irq <= 0 || dev->irq >= NR_IRQS)
+	if (dev->irq <= 0 || dev->irq >= nr_irqs)
 		printk(KERN_WARNING " *** Warning: IRQ %d is unlikely to work! ***\n",
 			   dev->irq);
 
diff --git a/drivers/net/hamradio/baycom_ser_fdx.c b/drivers/net/hamradio/baycom_ser_fdx.c
index 17ac6975d70..b6a816e60c0 100644
--- a/drivers/net/hamradio/baycom_ser_fdx.c
+++ b/drivers/net/hamradio/baycom_ser_fdx.c
@@ -416,10 +416,10 @@ static int ser12_open(struct net_device *dev)
 	if (!dev || !bc)
 		return -ENXIO;
 	if (!dev->base_addr || dev->base_addr > 0xffff-SER12_EXTENT ||
-	    dev->irq < 2 || dev->irq > NR_IRQS) {
+	    dev->irq < 2 || dev->irq > nr_irqs) {
 		printk(KERN_INFO "baycom_ser_fdx: invalid portnumber (max %u) "
 				"or irq (2 <= irq <= %d)\n",
-				0xffff-SER12_EXTENT, NR_IRQS);
+				0xffff-SER12_EXTENT, nr_irqs);
 		return -ENXIO;
 	}
 	if (bc->baud < 300 || bc->baud > 4800) {
diff --git a/drivers/net/hamradio/scc.c b/drivers/net/hamradio/scc.c
index 45ae9d1191d..c17e39bc546 100644
--- a/drivers/net/hamradio/scc.c
+++ b/drivers/net/hamradio/scc.c
@@ -1465,7 +1465,7 @@ static void z8530_init(void)
 	printk(KERN_INFO "Init Z8530 driver: %u channels, IRQ", Nchips*2);
 	
 	flag=" ";
-	for (k = 0; k < NR_IRQS; k++)
+	for (k = 0; k < nr_irqs; k++)
 		if (Ivec[k].used) 
 		{
 			printk("%s%d", flag, k);
@@ -1728,7 +1728,7 @@ static int scc_net_ioctl(struct net_device *dev, struct ifreq *ifr, int cmd)
 
 			if (hwcfg.irq == 2) hwcfg.irq = 9;
 
-			if (hwcfg.irq < 0 || hwcfg.irq >= NR_IRQS)
+			if (hwcfg.irq < 0 || hwcfg.irq >= nr_irqs)
 				return -EINVAL;
 				
 			if (!Ivec[hwcfg.irq].used && hwcfg.irq)
@@ -2148,7 +2148,7 @@ static void __exit scc_cleanup_driver(void)
 		}
 		
 	/* To unload the port must be closed so no real IRQ pending */
-	for (k=0; k < NR_IRQS ; k++)
+	for (k = 0; k < nr_irqs ; k++)
 		if (Ivec[k].used) free_irq(k, NULL);
 		
 	local_irq_enable();
diff --git a/drivers/net/wan/sbni.c b/drivers/net/wan/sbni.c
index f972fef87c9..ee51b6a5e60 100644
--- a/drivers/net/wan/sbni.c
+++ b/drivers/net/wan/sbni.c
@@ -318,7 +318,7 @@ sbni_pci_probe( struct net_device  *dev )
 				continue;
 		}
 
-		if( pci_irq_line <= 0  ||  pci_irq_line >= NR_IRQS )
+		if (pci_irq_line <= 0 || pci_irq_line >= nr_irqs)
 			printk( KERN_WARNING "  WARNING: The PCI BIOS assigned "
 				"this PCI card to IRQ %d, which is unlikely "
 				"to work!.\n"
diff --git a/drivers/parisc/dino.c b/drivers/parisc/dino.c
index fd56128525d..3bc54b30c3a 100644
--- a/drivers/parisc/dino.c
+++ b/drivers/parisc/dino.c
@@ -298,7 +298,8 @@ struct pci_port_ops dino_port_ops = {
 
 static void dino_disable_irq(unsigned int irq)
 {
-	struct dino_device *dino_dev = irq_desc[irq].chip_data;
+	struct irq_desc *desc = irq_to_desc(irq);
+	struct dino_device *dino_dev = desc->chip_data;
 	int local_irq = gsc_find_local_irq(irq, dino_dev->global_irq, DINO_LOCAL_IRQS);
 
 	DBG(KERN_WARNING "%s(0x%p, %d)\n", __func__, dino_dev, irq);
@@ -310,7 +311,8 @@ static void dino_disable_irq(unsigned int irq)
 
 static void dino_enable_irq(unsigned int irq)
 {
-	struct dino_device *dino_dev = irq_desc[irq].chip_data;
+	struct irq_desc *desc = irq_to_desc(irq);
+	struct dino_device *dino_dev = desc->chip_data;
 	int local_irq = gsc_find_local_irq(irq, dino_dev->global_irq, DINO_LOCAL_IRQS);
 	u32 tmp;
 
diff --git a/drivers/parisc/eisa.c b/drivers/parisc/eisa.c
index 771cef59254..7891db50c48 100644
--- a/drivers/parisc/eisa.c
+++ b/drivers/parisc/eisa.c
@@ -346,10 +346,10 @@ static int __init eisa_probe(struct parisc_device *dev)
 	}
 	
 	/* Reserve IRQ2 */
-	irq_desc[2].action = &irq2_action;
+	irq_to_desc(2)->action = &irq2_action;
 	
 	for (i = 0; i < 16; i++) {
-		irq_desc[i].chip = &eisa_interrupt_type;
+		irq_to_desc(i)->chip = &eisa_interrupt_type;
 	}
 	
 	EISA_bus = 1;
diff --git a/drivers/parisc/gsc.c b/drivers/parisc/gsc.c
index f7d088b897e..e76db9e4d50 100644
--- a/drivers/parisc/gsc.c
+++ b/drivers/parisc/gsc.c
@@ -108,7 +108,8 @@ int gsc_find_local_irq(unsigned int irq, int *global_irqs, int limit)
 
 static void gsc_asic_disable_irq(unsigned int irq)
 {
-	struct gsc_asic *irq_dev = irq_desc[irq].chip_data;
+	struct irq_desc *desc = irq_to_desc(irq);
+	struct gsc_asic *irq_dev = desc->chip_data;
 	int local_irq = gsc_find_local_irq(irq, irq_dev->global_irq, 32);
 	u32 imr;
 
@@ -123,7 +124,8 @@ static void gsc_asic_disable_irq(unsigned int irq)
 
 static void gsc_asic_enable_irq(unsigned int irq)
 {
-	struct gsc_asic *irq_dev = irq_desc[irq].chip_data;
+	struct irq_desc *desc = irq_to_desc(irq);
+	struct gsc_asic *irq_dev = desc->chip_data;
 	int local_irq = gsc_find_local_irq(irq, irq_dev->global_irq, 32);
 	u32 imr;
 
@@ -159,12 +161,14 @@ static struct hw_interrupt_type gsc_asic_interrupt_type = {
 int gsc_assign_irq(struct hw_interrupt_type *type, void *data)
 {
 	static int irq = GSC_IRQ_BASE;
+	struct irq_desc *desc;
 
 	if (irq > GSC_IRQ_MAX)
 		return NO_IRQ;
 
-	irq_desc[irq].chip = type;
-	irq_desc[irq].chip_data = data;
+	desc = irq_to_desc(irq);
+	desc->chip = type;
+	desc->chip_data = data;
 	return irq++;
 }
 
diff --git a/drivers/parisc/iosapic.c b/drivers/parisc/iosapic.c
index 6fb3f7979f2..7beffcab274 100644
--- a/drivers/parisc/iosapic.c
+++ b/drivers/parisc/iosapic.c
@@ -619,7 +619,9 @@ iosapic_set_irt_data( struct vector_info *vi, u32 *dp0, u32 *dp1)
 
 static struct vector_info *iosapic_get_vector(unsigned int irq)
 {
-	return irq_desc[irq].chip_data;
+	struct irq_desc *desc = irq_to_desc(irq);
+
+	return desc->chip_data;
 }
 
 static void iosapic_disable_irq(unsigned int irq)
diff --git a/drivers/parisc/superio.c b/drivers/parisc/superio.c
index 1e8d2d17f04..1e93c837514 100644
--- a/drivers/parisc/superio.c
+++ b/drivers/parisc/superio.c
@@ -363,7 +363,9 @@ int superio_fixup_irq(struct pci_dev *pcidev)
 #endif
 
 	for (i = 0; i < 16; i++) {
-		irq_desc[i].chip = &superio_interrupt_type;
+		struct irq_desc *desc = irq_to_desc(i);
+
+		desc->chip = &superio_interrupt_type;
 	}
 
 	/*
diff --git a/drivers/pci/dmar.c b/drivers/pci/dmar.c
index e842e756308..8b29c307f1a 100644
--- a/drivers/pci/dmar.c
+++ b/drivers/pci/dmar.c
@@ -193,7 +193,7 @@ dmar_parse_dev(struct dmar_drhd_unit *dmaru)
 {
 	struct acpi_dmar_hardware_unit *drhd;
 	static int include_all;
-	int ret;
+	int ret = 0;
 
 	drhd = (struct acpi_dmar_hardware_unit *) dmaru->hdr;
 
@@ -212,7 +212,7 @@ dmar_parse_dev(struct dmar_drhd_unit *dmaru)
 		include_all = 1;
 	}
 
-	if (ret || (dmaru->devices_cnt == 0 && !dmaru->include_all)) {
+	if (ret) {
 		list_del(&dmaru->list);
 		kfree(dmaru);
 	}
@@ -289,6 +289,24 @@ dmar_table_print_dmar_entry(struct acpi_dmar_header *header)
 	}
 }
 
+/**
+ * dmar_table_detect - checks to see if the platform supports DMAR devices
+ */
+static int __init dmar_table_detect(void)
+{
+	acpi_status status = AE_OK;
+
+	/* if we could find DMAR table, then there are DMAR devices */
+	status = acpi_get_table(ACPI_SIG_DMAR, 0,
+				(struct acpi_table_header **)&dmar_tbl);
+
+	if (ACPI_SUCCESS(status) && !dmar_tbl) {
+		printk (KERN_WARNING PREFIX "Unable to map DMAR\n");
+		status = AE_NOT_FOUND;
+	}
+
+	return (ACPI_SUCCESS(status) ? 1 : 0);
+}
 
 /**
  * parse_dmar_table - parses the DMA reporting table
@@ -300,6 +318,12 @@ parse_dmar_table(void)
 	struct acpi_dmar_header *entry_header;
 	int ret = 0;
 
+	/*
+	 * Do it again, earlier dmar_tbl mapping could be mapped with
+	 * fixed map.
+	 */
+	dmar_table_detect();
+
 	dmar = (struct acpi_table_dmar *)dmar_tbl;
 	if (!dmar)
 		return -ENODEV;
@@ -373,10 +397,10 @@ dmar_find_matched_drhd_unit(struct pci_dev *dev)
 
 int __init dmar_dev_scope_init(void)
 {
-	struct dmar_drhd_unit *drhd;
+	struct dmar_drhd_unit *drhd, *drhd_n;
 	int ret = -ENODEV;
 
-	for_each_drhd_unit(drhd) {
+	list_for_each_entry_safe(drhd, drhd_n, &dmar_drhd_units, list) {
 		ret = dmar_parse_dev(drhd);
 		if (ret)
 			return ret;
@@ -384,8 +408,8 @@ int __init dmar_dev_scope_init(void)
 
 #ifdef CONFIG_DMAR
 	{
-		struct dmar_rmrr_unit *rmrr;
-		for_each_rmrr_units(rmrr) {
+		struct dmar_rmrr_unit *rmrr, *rmrr_n;
+		list_for_each_entry_safe(rmrr, rmrr_n, &dmar_rmrr_units, list) {
 			ret = rmrr_parse_dev(rmrr);
 			if (ret)
 				return ret;
@@ -430,30 +454,11 @@ int __init dmar_table_init(void)
 	return 0;
 }
 
-/**
- * early_dmar_detect - checks to see if the platform supports DMAR devices
- */
-int __init early_dmar_detect(void)
-{
-	acpi_status status = AE_OK;
-
-	/* if we could find DMAR table, then there are DMAR devices */
-	status = acpi_get_table(ACPI_SIG_DMAR, 0,
-				(struct acpi_table_header **)&dmar_tbl);
-
-	if (ACPI_SUCCESS(status) && !dmar_tbl) {
-		printk (KERN_WARNING PREFIX "Unable to map DMAR\n");
-		status = AE_NOT_FOUND;
-	}
-
-	return (ACPI_SUCCESS(status) ? 1 : 0);
-}
-
 void __init detect_intel_iommu(void)
 {
 	int ret;
 
-	ret = early_dmar_detect();
+	ret = dmar_table_detect();
 
 #ifdef CONFIG_DMAR
 	{
@@ -479,14 +484,16 @@ void __init detect_intel_iommu(void)
 			       " x2apic support\n");
 
 			dmar_disabled = 1;
-			return;
+			goto end;
 		}
 
 		if (ret && !no_iommu && !iommu_detected && !swiotlb &&
 		    !dmar_disabled)
 			iommu_detected = 1;
 	}
+end:
 #endif
+	dmar_tbl = NULL;
 }
 
 
diff --git a/drivers/pci/htirq.c b/drivers/pci/htirq.c
index 279c940a003..bf7d6ce9bbb 100644
--- a/drivers/pci/htirq.c
+++ b/drivers/pci/htirq.c
@@ -126,7 +126,8 @@ int __ht_create_irq(struct pci_dev *dev, int idx, ht_irq_update_t *update)
 	cfg->msg.address_hi = 0xffffffff;
 
 	irq = create_irq();
-	if (irq < 0) {
+
+	if (irq <= 0) {
 		kfree(cfg);
 		return -EBUSY;
 	}
diff --git a/drivers/pci/intr_remapping.c b/drivers/pci/intr_remapping.c
index 738d4c89581..2de5a3238c9 100644
--- a/drivers/pci/intr_remapping.c
+++ b/drivers/pci/intr_remapping.c
@@ -1,3 +1,4 @@
+#include <linux/interrupt.h>
 #include <linux/dmar.h>
 #include <linux/spinlock.h>
 #include <linux/jiffies.h>
@@ -11,41 +12,64 @@ static struct ioapic_scope ir_ioapic[MAX_IO_APICS];
 static int ir_ioapic_num;
 int intr_remapping_enabled;
 
-static struct {
+struct irq_2_iommu {
 	struct intel_iommu *iommu;
 	u16 irte_index;
 	u16 sub_handle;
 	u8  irte_mask;
-} irq_2_iommu[NR_IRQS];
+};
+
+static struct irq_2_iommu irq_2_iommuX[NR_IRQS];
+
+static struct irq_2_iommu *irq_2_iommu(unsigned int irq)
+{
+	return (irq < nr_irqs) ? irq_2_iommuX + irq : NULL;
+}
+
+static struct irq_2_iommu *irq_2_iommu_alloc(unsigned int irq)
+{
+	return irq_2_iommu(irq);
+}
 
 static DEFINE_SPINLOCK(irq_2_ir_lock);
 
-int irq_remapped(int irq)
+static struct irq_2_iommu *valid_irq_2_iommu(unsigned int irq)
 {
-	if (irq > NR_IRQS)
-		return 0;
+	struct irq_2_iommu *irq_iommu;
+
+	irq_iommu = irq_2_iommu(irq);
+
+	if (!irq_iommu)
+		return NULL;
+
+	if (!irq_iommu->iommu)
+		return NULL;
 
-	if (!irq_2_iommu[irq].iommu)
-		return 0;
+	return irq_iommu;
+}
 
-	return 1;
+int irq_remapped(int irq)
+{
+	return valid_irq_2_iommu(irq) != NULL;
 }
 
 int get_irte(int irq, struct irte *entry)
 {
 	int index;
+	struct irq_2_iommu *irq_iommu;
 
-	if (!entry || irq > NR_IRQS)
+	if (!entry)
 		return -1;
 
 	spin_lock(&irq_2_ir_lock);
-	if (!irq_2_iommu[irq].iommu) {
+	irq_iommu = valid_irq_2_iommu(irq);
+	if (!irq_iommu) {
 		spin_unlock(&irq_2_ir_lock);
 		return -1;
 	}
 
-	index = irq_2_iommu[irq].irte_index + irq_2_iommu[irq].sub_handle;
-	*entry = *(irq_2_iommu[irq].iommu->ir_table->base + index);
+	index = irq_iommu->irte_index + irq_iommu->sub_handle;
+	*entry = *(irq_iommu->iommu->ir_table->base + index);
 
 	spin_unlock(&irq_2_ir_lock);
 	return 0;
@@ -54,6 +78,7 @@ int get_irte(int irq, struct irte *entry)
 int alloc_irte(struct intel_iommu *iommu, int irq, u16 count)
 {
 	struct ir_table *table = iommu->ir_table;
+	struct irq_2_iommu *irq_iommu;
 	u16 index, start_index;
 	unsigned int mask = 0;
 	int i;
@@ -61,6 +86,10 @@ int alloc_irte(struct intel_iommu *iommu, int irq, u16 count)
 	if (!count)
 		return -1;
 
+	/* protect irq_2_iommu_alloc later */
+	if (irq >= nr_irqs)
+		return -1;
+
 	/*
 	 * start the IRTE search from index 0.
 	 */
@@ -100,10 +129,11 @@ int alloc_irte(struct intel_iommu *iommu, int irq, u16 count)
 	for (i = index; i < index + count; i++)
 		table->base[i].present = 1;
 
-	irq_2_iommu[irq].iommu = iommu;
-	irq_2_iommu[irq].irte_index =  index;
-	irq_2_iommu[irq].sub_handle = 0;
-	irq_2_iommu[irq].irte_mask = mask;
+	irq_iommu = irq_2_iommu_alloc(irq);
+	irq_iommu->iommu = iommu;
+	irq_iommu->irte_index =  index;
+	irq_iommu->sub_handle = 0;
+	irq_iommu->irte_mask = mask;
 
 	spin_unlock(&irq_2_ir_lock);
 
@@ -124,31 +154,33 @@ static void qi_flush_iec(struct intel_iommu *iommu, int index, int mask)
 int map_irq_to_irte_handle(int irq, u16 *sub_handle)
 {
 	int index;
+	struct irq_2_iommu *irq_iommu;
 
 	spin_lock(&irq_2_ir_lock);
-	if (irq >= NR_IRQS || !irq_2_iommu[irq].iommu) {
+	irq_iommu = valid_irq_2_iommu(irq);
+	if (!irq_iommu) {
 		spin_unlock(&irq_2_ir_lock);
 		return -1;
 	}
 
-	*sub_handle = irq_2_iommu[irq].sub_handle;
-	index = irq_2_iommu[irq].irte_index;
+	*sub_handle = irq_iommu->sub_handle;
+	index = irq_iommu->irte_index;
 	spin_unlock(&irq_2_ir_lock);
 	return index;
 }
 
 int set_irte_irq(int irq, struct intel_iommu *iommu, u16 index, u16 subhandle)
 {
+	struct irq_2_iommu *irq_iommu;
+
 	spin_lock(&irq_2_ir_lock);
-	if (irq >= NR_IRQS || irq_2_iommu[irq].iommu) {
-		spin_unlock(&irq_2_ir_lock);
-		return -1;
-	}
 
-	irq_2_iommu[irq].iommu = iommu;
-	irq_2_iommu[irq].irte_index = index;
-	irq_2_iommu[irq].sub_handle = subhandle;
-	irq_2_iommu[irq].irte_mask = 0;
+	irq_iommu = irq_2_iommu_alloc(irq);
+
+	irq_iommu->iommu = iommu;
+	irq_iommu->irte_index = index;
+	irq_iommu->sub_handle = subhandle;
+	irq_iommu->irte_mask = 0;
 
 	spin_unlock(&irq_2_ir_lock);
 
@@ -157,16 +189,19 @@ int set_irte_irq(int irq, struct intel_iommu *iommu, u16 index, u16 subhandle)
 
 int clear_irte_irq(int irq, struct intel_iommu *iommu, u16 index)
 {
+	struct irq_2_iommu *irq_iommu;
+
 	spin_lock(&irq_2_ir_lock);
-	if (irq >= NR_IRQS || !irq_2_iommu[irq].iommu) {
+	irq_iommu = valid_irq_2_iommu(irq);
+	if (!irq_iommu) {
 		spin_unlock(&irq_2_ir_lock);
 		return -1;
 	}
 
-	irq_2_iommu[irq].iommu = NULL;
-	irq_2_iommu[irq].irte_index = 0;
-	irq_2_iommu[irq].sub_handle = 0;
-	irq_2_iommu[irq].irte_mask = 0;
+	irq_iommu->iommu = NULL;
+	irq_iommu->irte_index = 0;
+	irq_iommu->sub_handle = 0;
+	irq_2_iommu(irq)->irte_mask = 0;
 
 	spin_unlock(&irq_2_ir_lock);
 
@@ -178,16 +213,18 @@ int modify_irte(int irq, struct irte *irte_modified)
 	int index;
 	struct irte *irte;
 	struct intel_iommu *iommu;
+	struct irq_2_iommu *irq_iommu;
 
 	spin_lock(&irq_2_ir_lock);
-	if (irq >= NR_IRQS || !irq_2_iommu[irq].iommu) {
+	irq_iommu = valid_irq_2_iommu(irq);
+	if (!irq_iommu) {
 		spin_unlock(&irq_2_ir_lock);
 		return -1;
 	}
 
-	iommu = irq_2_iommu[irq].iommu;
+	iommu = irq_iommu->iommu;
 
-	index = irq_2_iommu[irq].irte_index + irq_2_iommu[irq].sub_handle;
+	index = irq_iommu->irte_index + irq_iommu->sub_handle;
 	irte = &iommu->ir_table->base[index];
 
 	set_64bit((unsigned long *)irte, irte_modified->low | (1 << 1));
@@ -203,18 +240,20 @@ int flush_irte(int irq)
 {
 	int index;
 	struct intel_iommu *iommu;
+	struct irq_2_iommu *irq_iommu;
 
 	spin_lock(&irq_2_ir_lock);
-	if (irq >= NR_IRQS || !irq_2_iommu[irq].iommu) {
+	irq_iommu = valid_irq_2_iommu(irq);
+	if (!irq_iommu) {
 		spin_unlock(&irq_2_ir_lock);
 		return -1;
 	}
 
-	iommu = irq_2_iommu[irq].iommu;
+	iommu = irq_iommu->iommu;
 
-	index = irq_2_iommu[irq].irte_index + irq_2_iommu[irq].sub_handle;
+	index = irq_iommu->irte_index + irq_iommu->sub_handle;
 
-	qi_flush_iec(iommu, index, irq_2_iommu[irq].irte_mask);
+	qi_flush_iec(iommu, index, irq_iommu->irte_mask);
 	spin_unlock(&irq_2_ir_lock);
 
 	return 0;
@@ -246,28 +285,30 @@ int free_irte(int irq)
 	int index, i;
 	struct irte *irte;
 	struct intel_iommu *iommu;
+	struct irq_2_iommu *irq_iommu;
 
 	spin_lock(&irq_2_ir_lock);
-	if (irq >= NR_IRQS || !irq_2_iommu[irq].iommu) {
+	irq_iommu = valid_irq_2_iommu(irq);
+	if (!irq_iommu) {
 		spin_unlock(&irq_2_ir_lock);
 		return -1;
 	}
 
-	iommu = irq_2_iommu[irq].iommu;
+	iommu = irq_iommu->iommu;
 
-	index = irq_2_iommu[irq].irte_index + irq_2_iommu[irq].sub_handle;
+	index = irq_iommu->irte_index + irq_iommu->sub_handle;
 	irte = &iommu->ir_table->base[index];
 
-	if (!irq_2_iommu[irq].sub_handle) {
-		for (i = 0; i < (1 << irq_2_iommu[irq].irte_mask); i++)
+	if (!irq_iommu->sub_handle) {
+		for (i = 0; i < (1 << irq_iommu->irte_mask); i++)
 			set_64bit((unsigned long *)irte, 0);
-		qi_flush_iec(iommu, index, irq_2_iommu[irq].irte_mask);
+		qi_flush_iec(iommu, index, irq_iommu->irte_mask);
 	}
 
-	irq_2_iommu[irq].iommu = NULL;
-	irq_2_iommu[irq].irte_index = 0;
-	irq_2_iommu[irq].sub_handle = 0;
-	irq_2_iommu[irq].irte_mask = 0;
+	irq_iommu->iommu = NULL;
+	irq_iommu->irte_index = 0;
+	irq_iommu->sub_handle = 0;
+	irq_iommu->irte_mask = 0;
 
 	spin_unlock(&irq_2_ir_lock);
 
diff --git a/drivers/pcmcia/at91_cf.c b/drivers/pcmcia/at91_cf.c
index a0ffb8ebfe0..9e1140f085f 100644
--- a/drivers/pcmcia/at91_cf.c
+++ b/drivers/pcmcia/at91_cf.c
@@ -273,7 +273,7 @@ static int __init at91_cf_probe(struct platform_device *pdev)
 			goto fail0d;
 		cf->socket.pci_irq = board->irq_pin;
 	} else
-		cf->socket.pci_irq = NR_IRQS + 1;
+		cf->socket.pci_irq = nr_irqs + 1;
 
 	/* pcmcia layer only remaps "real" memory not iospace */
 	cf->socket.io_offset = (unsigned long)
diff --git a/drivers/pcmcia/hd64465_ss.c b/drivers/pcmcia/hd64465_ss.c
index 117dc12ab43..9ef69cdb318 100644
--- a/drivers/pcmcia/hd64465_ss.c
+++ b/drivers/pcmcia/hd64465_ss.c
@@ -233,15 +233,18 @@ static struct hw_interrupt_type hd64465_ss_irq_type = {
  */
 static void hs_map_irq(hs_socket_t *sp, unsigned int irq)
 {
+	struct irq_desc *desc;
+
     	DPRINTK("hs_map_irq(sock=%d irq=%d)\n", sp->number, irq);
 	
 	if (irq >= HS_NUM_MAPPED_IRQS)
 	    return;
 
+	desc = irq_to_desc(irq);
     	hs_mapped_irq[irq].sock = sp;
 	/* insert ourselves as the irq controller */
-	hs_mapped_irq[irq].old_handler = irq_desc[irq].chip;
-	irq_desc[irq].chip = &hd64465_ss_irq_type;
+	hs_mapped_irq[irq].old_handler = desc->chip;
+	desc->chip = &hd64465_ss_irq_type;
 }
 
 
@@ -250,13 +253,16 @@ static void hs_map_irq(hs_socket_t *sp, unsigned int irq)
  */
 static void hs_unmap_irq(hs_socket_t *sp, unsigned int irq)
 {
+	struct irq_desc *desc;
+
     	DPRINTK("hs_unmap_irq(sock=%d irq=%d)\n", sp->number, irq);
 	
 	if (irq >= HS_NUM_MAPPED_IRQS)
 	    return;
 		
+	desc = irq_to_desc(irq);
 	/* restore the original irq controller */
-	irq_desc[irq].chip = hs_mapped_irq[irq].old_handler;
+	desc->chip = hs_mapped_irq[irq].old_handler;
 }
 
 /*============================================================*/
diff --git a/drivers/pcmcia/vrc4171_card.c b/drivers/pcmcia/vrc4171_card.c
index eee2f1cb213..b2c41241905 100644
--- a/drivers/pcmcia/vrc4171_card.c
+++ b/drivers/pcmcia/vrc4171_card.c
@@ -639,7 +639,7 @@ static int __devinit vrc4171_card_setup(char *options)
 		int irq;
 		options += 4;
 		irq = simple_strtoul(options, &options, 0);
-		if (irq >= 0 && irq < NR_IRQS)
+		if (irq >= 0 && irq < nr_irqs)
 			vrc4171_irq = irq;
 
 		if (*options != ',')
diff --git a/drivers/rtc/rtc-vr41xx.c b/drivers/rtc/rtc-vr41xx.c
index 884b635f028..834dcc6d785 100644
--- a/drivers/rtc/rtc-vr41xx.c
+++ b/drivers/rtc/rtc-vr41xx.c
@@ -360,7 +360,7 @@ static int __devinit rtc_probe(struct platform_device *pdev)
 	spin_unlock_irq(&rtc_lock);
 
 	aie_irq = platform_get_irq(pdev, 0);
-	if (aie_irq < 0 || aie_irq >= NR_IRQS) {
+	if (aie_irq < 0 || aie_irq >= nr_irqs) {
 		retval = -EBUSY;
 		goto err_device_unregister;
 	}
@@ -371,7 +371,7 @@ static int __devinit rtc_probe(struct platform_device *pdev)
 		goto err_device_unregister;
 
 	pie_irq = platform_get_irq(pdev, 1);
-	if (pie_irq < 0 || pie_irq >= NR_IRQS)
+	if (pie_irq < 0 || pie_irq >= nr_irqs)
 		goto err_free_irq;
 
 	retval = request_irq(pie_irq, rtclong1_interrupt, IRQF_DISABLED,
diff --git a/drivers/scsi/aha152x.c b/drivers/scsi/aha152x.c
index b5a868d85eb..1e5478abd90 100644
--- a/drivers/scsi/aha152x.c
+++ b/drivers/scsi/aha152x.c
@@ -337,7 +337,7 @@ CMD_INC_RESID(struct scsi_cmnd *cmd, int inc)
 #else
 #define IRQ_MIN 9
 #if defined(__PPC)
-#define IRQ_MAX (NR_IRQS-1)
+#define IRQ_MAX (nr_irqs-1)
 #else
 #define IRQ_MAX 12
 #endif
diff --git a/drivers/scsi/qla2xxx/qla_def.h b/drivers/scsi/qla2xxx/qla_def.h
index 83c81921677..f25f41a499e 100644
--- a/drivers/scsi/qla2xxx/qla_def.h
+++ b/drivers/scsi/qla2xxx/qla_def.h
@@ -2108,7 +2108,7 @@ struct scsi_qla_host;
 
 struct qla_msix_entry {
 	int have_irq;
-	uint16_t msix_vector;
+	uint32_t msix_vector;
 	uint16_t msix_entry;
 };
 
diff --git a/drivers/serial/68328serial.c b/drivers/serial/68328serial.c
index 381b12ac20e..d935b2d04f9 100644
--- a/drivers/serial/68328serial.c
+++ b/drivers/serial/68328serial.c
@@ -66,7 +66,6 @@
 #endif
 
 static struct m68k_serial m68k_soft[NR_PORTS];
-struct m68k_serial *IRQ_ports[NR_IRQS];
 
 static unsigned int uart_irqs[NR_PORTS] = UART_IRQ_DEFNS;
 
@@ -375,15 +374,11 @@ clear_and_return:
  */
 irqreturn_t rs_interrupt(int irq, void *dev_id)
 {
-	struct m68k_serial * info;
+	struct m68k_serial *info = dev_id;
 	m68328_uart *uart;
 	unsigned short rx;
 	unsigned short tx;
 
-	info = IRQ_ports[irq];
-	if(!info)
-	    return IRQ_NONE;
-
 	uart = &uart_addr[info->line];
 	rx = uart->urx.w;
 
@@ -1383,8 +1378,6 @@ rs68328_init(void)
 		   info->port, info->irq);
 	    printk(" is a builtin MC68328 UART\n");
 	    
-	    IRQ_ports[info->irq] = info;	/* waste of space */
-
 #ifdef CONFIG_M68VZ328
 		if (i > 0 )
 			PJSEL &= 0xCF;  /* PSW enable second port output */
@@ -1393,7 +1386,7 @@ rs68328_init(void)
 	    if (request_irq(uart_irqs[i],
 			    rs_interrupt,
 			    IRQF_DISABLED,
-			    "M68328_UART", NULL))
+			    "M68328_UART", info))
                 panic("Unable to attach 68328 serial interrupt\n");
 	}
 	local_irq_restore(flags);
diff --git a/drivers/serial/8250.c b/drivers/serial/8250.c
index 1528de23a65..303272af386 100644
--- a/drivers/serial/8250.c
+++ b/drivers/serial/8250.c
@@ -156,11 +156,15 @@ struct uart_8250_port {
 };
 
 struct irq_info {
-	spinlock_t		lock;
+	struct			hlist_node node;
+	int			irq;
+	spinlock_t		lock;	/* Protects list not the hash */
 	struct list_head	*head;
 };
 
-static struct irq_info irq_lists[NR_IRQS];
+#define NR_IRQ_HASH		32	/* Can be adjusted later */
+static struct hlist_head irq_lists[NR_IRQ_HASH];
+static DEFINE_MUTEX(hash_mutex);	/* Used to walk the hash */
 
 /*
  * Here we define the default xmit fifo size used for each type of UART.
@@ -1545,15 +1549,43 @@ static void serial_do_unlink(struct irq_info *i, struct uart_8250_port *up)
 		BUG_ON(i->head != &up->list);
 		i->head = NULL;
 	}
-
 	spin_unlock_irq(&i->lock);
+	/* List empty so throw away the hash node */
+	if (i->head == NULL) {
+		hlist_del(&i->node);
+		kfree(i);
+	}
 }
 
 static int serial_link_irq_chain(struct uart_8250_port *up)
 {
-	struct irq_info *i = irq_lists + up->port.irq;
+	struct hlist_head *h;
+	struct hlist_node *n;
+	struct irq_info *i;
 	int ret, irq_flags = up->port.flags & UPF_SHARE_IRQ ? IRQF_SHARED : 0;
 
+	mutex_lock(&hash_mutex);
+
+	h = &irq_lists[up->port.irq % NR_IRQ_HASH];
+
+	hlist_for_each(n, h) {
+		i = hlist_entry(n, struct irq_info, node);
+		if (i->irq == up->port.irq)
+			break;
+	}
+
+	if (n == NULL) {
+		i = kzalloc(sizeof(struct irq_info), GFP_KERNEL);
+		if (i == NULL) {
+			mutex_unlock(&hash_mutex);
+			return -ENOMEM;
+		}
+		spin_lock_init(&i->lock);
+		i->irq = up->port.irq;
+		hlist_add_head(&i->node, h);
+	}
+	mutex_unlock(&hash_mutex);
+
 	spin_lock_irq(&i->lock);
 
 	if (i->head) {
@@ -1577,14 +1609,28 @@ static int serial_link_irq_chain(struct uart_8250_port *up)
 
 static void serial_unlink_irq_chain(struct uart_8250_port *up)
 {
-	struct irq_info *i = irq_lists + up->port.irq;
+	struct irq_info *i;
+	struct hlist_node *n;
+	struct hlist_head *h;
 
+	mutex_lock(&hash_mutex);
+
+	h = &irq_lists[up->port.irq % NR_IRQ_HASH];
+
+	hlist_for_each(n, h) {
+		i = hlist_entry(n, struct irq_info, node);
+		if (i->irq == up->port.irq)
+			break;
+	}
+
+	BUG_ON(n == NULL);
 	BUG_ON(i->head == NULL);
 
 	if (list_empty(i->head))
 		free_irq(up->port.irq, i);
 
 	serial_do_unlink(i, up);
+	mutex_unlock(&hash_mutex);
 }
 
 /* Base timer interval for polling */
@@ -2447,7 +2493,7 @@ static void serial8250_config_port(struct uart_port *port, int flags)
 static int
 serial8250_verify_port(struct uart_port *port, struct serial_struct *ser)
 {
-	if (ser->irq >= NR_IRQS || ser->irq < 0 ||
+	if (ser->irq >= nr_irqs || ser->irq < 0 ||
 	    ser->baud_base < 9600 || ser->type < PORT_UNKNOWN ||
 	    ser->type >= ARRAY_SIZE(uart_config) || ser->type == PORT_CIRRUS ||
 	    ser->type == PORT_STARTECH)
@@ -2967,7 +3013,7 @@ EXPORT_SYMBOL(serial8250_unregister_port);
 
 static int __init serial8250_init(void)
 {
-	int ret, i;
+	int ret;
 
 	if (nr_uarts > UART_NR)
 		nr_uarts = UART_NR;
@@ -2976,9 +3022,6 @@ static int __init serial8250_init(void)
 		"%d ports, IRQ sharing %sabled\n", nr_uarts,
 		share_irqs ? "en" : "dis");
 
-	for (i = 0; i < NR_IRQS; i++)
-		spin_lock_init(&irq_lists[i].lock);
-
 #ifdef CONFIG_SPARC
 	ret = sunserial_register_minors(&serial8250_reg, UART_NR);
 #else
@@ -3006,15 +3049,15 @@ static int __init serial8250_init(void)
 		goto out;
 
 	platform_device_del(serial8250_isa_devs);
- put_dev:
+put_dev:
 	platform_device_put(serial8250_isa_devs);
- unreg_uart_drv:
+unreg_uart_drv:
 #ifdef CONFIG_SPARC
 	sunserial_unregister_minors(&serial8250_reg, UART_NR);
 #else
 	uart_unregister_driver(&serial8250_reg);
 #endif
- out:
+out:
 	return ret;
 }
 
diff --git a/drivers/serial/amba-pl010.c b/drivers/serial/amba-pl010.c
index 90b56c2c31e..71562689116 100644
--- a/drivers/serial/amba-pl010.c
+++ b/drivers/serial/amba-pl010.c
@@ -512,7 +512,7 @@ static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
 	int ret = 0;
 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
 		ret = -EINVAL;
-	if (ser->irq < 0 || ser->irq >= NR_IRQS)
+	if (ser->irq < 0 || ser->irq >= nr_irqs)
 		ret = -EINVAL;
 	if (ser->baud_base < 9600)
 		ret = -EINVAL;
diff --git a/drivers/serial/amba-pl011.c b/drivers/serial/amba-pl011.c
index 9d08f27208a..b7180046f8d 100644
--- a/drivers/serial/amba-pl011.c
+++ b/drivers/serial/amba-pl011.c
@@ -572,7 +572,7 @@ static int pl010_verify_port(struct uart_port *port, struct serial_struct *ser)
 	int ret = 0;
 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_AMBA)
 		ret = -EINVAL;
-	if (ser->irq < 0 || ser->irq >= NR_IRQS)
+	if (ser->irq < 0 || ser->irq >= nr_irqs)
 		ret = -EINVAL;
 	if (ser->baud_base < 9600)
 		ret = -EINVAL;
diff --git a/drivers/serial/cpm_uart/cpm_uart_core.c b/drivers/serial/cpm_uart/cpm_uart_core.c
index a6c4d744495..bde4b4b0b80 100644
--- a/drivers/serial/cpm_uart/cpm_uart_core.c
+++ b/drivers/serial/cpm_uart/cpm_uart_core.c
@@ -623,7 +623,7 @@ static int cpm_uart_verify_port(struct uart_port *port,
 
 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM)
 		ret = -EINVAL;
-	if (ser->irq < 0 || ser->irq >= NR_IRQS)
+	if (ser->irq < 0 || ser->irq >= nr_irqs)
 		ret = -EINVAL;
 	if (ser->baud_base < 9600)
 		ret = -EINVAL;
diff --git a/drivers/serial/m32r_sio.c b/drivers/serial/m32r_sio.c
index 23d03051101..611c97a1565 100644
--- a/drivers/serial/m32r_sio.c
+++ b/drivers/serial/m32r_sio.c
@@ -922,7 +922,7 @@ static void m32r_sio_config_port(struct uart_port *port, int flags)
 static int
 m32r_sio_verify_port(struct uart_port *port, struct serial_struct *ser)
 {
-	if (ser->irq >= NR_IRQS || ser->irq < 0 ||
+	if (ser->irq >= nr_irqs || ser->irq < 0 ||
 	    ser->baud_base < 9600 || ser->type < PORT_UNKNOWN ||
 	    ser->type >= ARRAY_SIZE(uart_config))
 		return -EINVAL;
@@ -1162,7 +1162,7 @@ static int __init m32r_sio_init(void)
 
 	printk(KERN_INFO "Serial: M32R SIO driver\n");
 
-	for (i = 0; i < NR_IRQS; i++)
+	for (i = 0; i < nr_irqs; i++)
 		spin_lock_init(&irq_lists[i].lock);
 
 	ret = uart_register_driver(&m32r_sio_reg);
diff --git a/drivers/serial/serial_core.c b/drivers/serial/serial_core.c
index 6bdf3362e3b..874786a11fe 100644
--- a/drivers/serial/serial_core.c
+++ b/drivers/serial/serial_core.c
@@ -741,7 +741,7 @@ static int uart_set_info(struct uart_state *state,
 	if (port->ops->verify_port)
 		retval = port->ops->verify_port(port, &new_serial);
 
-	if ((new_serial.irq >= NR_IRQS) || (new_serial.irq < 0) ||
+	if ((new_serial.irq >= nr_irqs) || (new_serial.irq < 0) ||
 	    (new_serial.baud_base < 9600))
 		retval = -EINVAL;
 
diff --git a/drivers/serial/serial_lh7a40x.c b/drivers/serial/serial_lh7a40x.c
index cb49a5ac022..61dc8b3daa2 100644
--- a/drivers/serial/serial_lh7a40x.c
+++ b/drivers/serial/serial_lh7a40x.c
@@ -460,7 +460,7 @@ static int lh7a40xuart_verify_port (struct uart_port* port,
 
 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_LH7A40X)
 		ret = -EINVAL;
-	if (ser->irq < 0 || ser->irq >= NR_IRQS)
+	if (ser->irq < 0 || ser->irq >= nr_irqs)
 		ret = -EINVAL;
 	if (ser->baud_base < 9600) /* *** FIXME: is this true? */
 		ret = -EINVAL;
diff --git a/drivers/serial/sh-sci.c b/drivers/serial/sh-sci.c
index 3b9d2d83b59..f0658d2c45b 100644
--- a/drivers/serial/sh-sci.c
+++ b/drivers/serial/sh-sci.c
@@ -1149,7 +1149,7 @@ static int sci_verify_port(struct uart_port *port, struct serial_struct *ser)
 {
 	struct sci_port *s = &sci_ports[port->line];
 
-	if (ser->irq != s->irqs[SCIx_TXI_IRQ] || ser->irq > NR_IRQS)
+	if (ser->irq != s->irqs[SCIx_TXI_IRQ] || ser->irq > nr_irqs)
 		return -EINVAL;
 	if (ser->baud_base < 2400)
 		/* No paper tape reader for Mitch.. */
diff --git a/drivers/serial/ucc_uart.c b/drivers/serial/ucc_uart.c
index 539c933b335..315a9333ca3 100644
--- a/drivers/serial/ucc_uart.c
+++ b/drivers/serial/ucc_uart.c
@@ -1066,7 +1066,7 @@ static int qe_uart_verify_port(struct uart_port *port,
 	if (ser->type != PORT_UNKNOWN && ser->type != PORT_CPM)
 		return -EINVAL;
 
-	if (ser->irq < 0 || ser->irq >= NR_IRQS)
+	if (ser->irq < 0 || ser->irq >= nr_irqs)
 		return -EINVAL;
 
 	if (ser->baud_base < 9600)
diff --git a/drivers/xen/events.c b/drivers/xen/events.c
index c3290bc186a..9ce1ab6c268 100644
--- a/drivers/xen/events.c
+++ b/drivers/xen/events.c
@@ -125,7 +125,7 @@ static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
 
 	BUG_ON(irq == -1);
 #ifdef CONFIG_SMP
-	irq_desc[irq].affinity = cpumask_of_cpu(cpu);
+	irq_to_desc(irq)->affinity = cpumask_of_cpu(cpu);
 #endif
 
 	__clear_bit(chn, cpu_evtchn_mask[cpu_evtchn[chn]]);
@@ -137,10 +137,12 @@ static void bind_evtchn_to_cpu(unsigned int chn, unsigned int cpu)
 static void init_evtchn_cpu_bindings(void)
 {
 #ifdef CONFIG_SMP
+	struct irq_desc *desc;
 	int i;
+
 	/* By default all event channels notify CPU#0. */
-	for (i = 0; i < NR_IRQS; i++)
-		irq_desc[i].affinity = cpumask_of_cpu(0);
+	for_each_irq_desc(i, desc)
+		desc->affinity = cpumask_of_cpu(0);
 #endif
 
 	memset(cpu_evtchn, 0, sizeof(cpu_evtchn));
@@ -229,12 +231,12 @@ static int find_unbound_irq(void)
 	int irq;
 
 	/* Only allocate from dynirq range */
-	for (irq = 0; irq < NR_IRQS; irq++)
+	for_each_irq_nr(irq)
 		if (irq_bindcount[irq] == 0)
 			break;
 
-	if (irq == NR_IRQS)
-		panic("No available IRQ to bind to: increase NR_IRQS!\n");
+	if (irq == nr_irqs)
+		panic("No available IRQ to bind to: increase nr_irqs!\n");
 
 	return irq;
 }
@@ -790,7 +792,7 @@ void xen_irq_resume(void)
 		mask_evtchn(evtchn);
 
 	/* No IRQ <-> event-channel mappings. */
-	for (irq = 0; irq < NR_IRQS; irq++)
+	for_each_irq_nr(irq)
 		irq_info[irq].evtchn = 0; /* zap event-channel binding */
 
 	for (evtchn = 0; evtchn < NR_EVENT_CHANNELS; evtchn++)
@@ -822,7 +824,7 @@ void __init xen_init_IRQ(void)
 		mask_evtchn(i);
 
 	/* Dynamic IRQ space is currently unbound. Zero the refcnts. */
-	for (i = 0; i < NR_IRQS; i++)
+	for_each_irq_nr(i)
 		irq_bindcount[i] = 0;
 
 	irq_ctx_init(smp_processor_id());