add CONFIG_HAVE_SPARSE_IRQ to for use condensed array
preallocate 32 irq_desc, and irq_desc() will try to get more.

v2: accrording to Eric, change get_irq_desc() to irq_desc()

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
---
 arch/Kconfig                                    |    4 +
 arch/alpha/kernel/irq.c                         |   19 ++-
 arch/alpha/kernel/irq_alpha.c                   |    5 +-
 arch/alpha/kernel/irq_i8259.c                   |    8 +-
 arch/alpha/kernel/irq_pyxis.c                   |    9 +-
 arch/alpha/kernel/irq_srm.c                     |    9 +-
 arch/alpha/kernel/sys_alcor.c                   |    9 +-
 arch/alpha/kernel/sys_cabriolet.c               |    8 +-
 arch/alpha/kernel/sys_dp264.c                   |    9 +-
 arch/alpha/kernel/sys_eb64p.c                   |    8 +-
 arch/alpha/kernel/sys_eiger.c                   |    7 +-
 arch/alpha/kernel/sys_jensen.c                  |   21 ++--
 arch/alpha/kernel/sys_marvel.c                  |   20 ++-
 arch/alpha/kernel/sys_mikasa.c                  |    8 +-
 arch/alpha/kernel/sys_noritake.c                |    8 +-
 arch/alpha/kernel/sys_rawhide.c                 |    8 +-
 arch/alpha/kernel/sys_rx164.c                   |    8 +-
 arch/alpha/kernel/sys_sable.c                   |    8 +-
 arch/alpha/kernel/sys_takara.c                  |    8 +-
 arch/alpha/kernel/sys_titan.c                   |    8 +-
 arch/alpha/kernel/sys_wildfire.c                |   19 ++--
 arch/arm/common/gic.c                           |    2 +-
 arch/arm/kernel/irq.c                           |   12 +-
 arch/arm/mach-at91/gpio.c                       |    4 +-
 arch/arm/mach-davinci/gpio.c                    |   13 ++-
 arch/arm/mach-ep93xx/core.c                     |    4 +-
 arch/arm/mach-orion5x/irq.c                     |    8 +-
 arch/arm/mach-sa1100/h3600.c                    |   10 +-
 arch/arm/plat-mxc/gpio.c                        |    7 +-
 arch/arm/plat-omap/gpio.c                       |   10 +-
 arch/arm/plat-orion/irq.c                       |    2 +-
 arch/avr32/kernel/irq.c                         |   10 +-
 arch/avr32/mach-at32ap/extint.c                 |    7 +-
 arch/avr32/mach-at32ap/pio.c                    |    2 +-
 arch/blackfin/kernel/irqchip.c                  |    8 +-
 arch/blackfin/kernel/traps.c                    |    8 +-
 arch/blackfin/mach-bf527/boards/cm_bf527.c      |    2 +-
 arch/blackfin/mach-bf527/boards/ezkit.c         |    2 +-
 arch/blackfin/mach-bf533/boards/cm_bf533.c      |    2 +-
 arch/blackfin/mach-bf533/boards/ezkit.c         |    2 +-
 arch/blackfin/mach-bf533/boards/stamp.c         |    2 +-
 arch/blackfin/mach-bf537/boards/cm_bf537.c      |    2 +-
 arch/blackfin/mach-bf537/boards/generic_board.c |    2 +-
 arch/blackfin/mach-bf537/boards/stamp.c         |    2 +-
 arch/blackfin/mach-bf561/boards/cm_bf561.c      |    2 +-
 arch/blackfin/mach-bf561/boards/ezkit.c         |    2 +-
 arch/cris/arch-v10/kernel/irq.c                 |    2 +-
 arch/cris/arch-v32/kernel/irq.c                 |    6 +-
 arch/cris/kernel/irq.c                          |   10 +-
 arch/frv/kernel/irq.c                           |   10 +-
 arch/h8300/kernel/irq.c                         |   22 ++--
 arch/ia64/kernel/iosapic.c                      |   11 +-
 arch/ia64/kernel/irq.c                          |   16 ++-
 arch/ia64/kernel/msi_ia64.c                     |    2 +-
 arch/ia64/sn/kernel/irq.c                       |    2 +-
 arch/ia64/sn/kernel/msi_sn.c                    |    2 +-
 arch/m32r/kernel/irq.c                          |   10 +-
 arch/m32r/platforms/m32104ut/setup.c            |   37 +++---
 arch/m32r/platforms/m32700ut/setup.c            |  133 +++++++++++---------
 arch/m32r/platforms/mappi/setup.c               |   84 ++++++++-----
 arch/m32r/platforms/mappi2/setup.c              |  103 ++++++++++------
 arch/m32r/platforms/mappi3/setup.c              |  103 ++++++++++------
 arch/m32r/platforms/oaks32r/setup.c             |   62 ++++++----
 arch/m32r/platforms/opsput/setup.c              |  149 ++++++++++++++---------
 arch/m32r/platforms/usrv/setup.c                |   92 +++++++++------
 arch/m68knommu/kernel/irq.c                     |   16 ++-
 arch/mips/au1000/common/irq.c                   |    2 +-
 arch/mips/dec/ioasic-irq.c                      |    2 +-
 arch/mips/emma2rh/markeins/irq_markeins.c       |    2 +-
 arch/mips/kernel/irq-gic.c                      |    2 +-
 arch/mips/kernel/irq-msc01.c                    |    2 +-
 arch/mips/kernel/irq.c                          |   10 +-
 arch/mips/kernel/smtc.c                         |    2 +-
 arch/mips/mti-malta/malta-smtc.c                |    2 +-
 arch/mips/sgi-ip32/ip32-irq.c                   |   10 +-
 arch/mips/sibyte/bcm1480/irq.c                  |    2 +-
 arch/mips/sibyte/sb1250/irq.c                   |    2 +-
 arch/mips/sni/a20r.c                            |    2 +-
 arch/mips/sni/pcimt.c                           |    2 +-
 arch/mips/sni/pcit.c                            |    2 +-
 arch/mips/sni/rm200.c                           |    2 +-
 arch/mn10300/kernel/irq.c                       |   12 +-
 arch/parisc/kernel/irq.c                        |   41 ++++---
 arch/powerpc/kernel/irq.c                       |   11 +-
 arch/powerpc/platforms/powermac/pic.c           |    2 +-
 arch/powerpc/platforms/pseries/xics.c           |    4 +-
 arch/powerpc/sysdev/cpm2_pic.c                  |    5 +-
 arch/powerpc/sysdev/mpic.c                      |   16 ++--
 arch/powerpc/sysdev/qe_lib/qe_ic.c              |    2 +-
 arch/sh/boards/cayman/irq.c                     |    4 +-
 arch/sh/boards/dreamcast/irq.c                  |    2 +-
 arch/sh/boards/dreamcast/setup.c                |    2 +-
 arch/sh/boards/renesas/systemh/irq.c            |    4 +-
 arch/sh/boards/se/7206/irq.c                    |    2 +-
 arch/sh/boards/superh/microdev/irq.c            |    4 +-
 arch/sh/cchips/hd6446x/hd64461.c                |    4 +-
 arch/sh/cchips/hd6446x/hd64465/setup.c          |    4 +-
 arch/sh/kernel/cpu/irq/imask.c                  |    4 +-
 arch/sh/kernel/cpu/irq/intc-sh5.c               |    4 +-
 arch/sh/kernel/irq.c                            |   12 +-
 arch/sparc64/kernel/irq.c                       |   31 +++--
 arch/um/kernel/irq.c                            |   29 +++--
 arch/x86/Kconfig                                |    1 +
 arch/x86/kernel/io_apic_32.c                    |   46 +++++--
 arch/x86/kernel/io_apic_64.c                    |   75 ++++++++----
 arch/x86/kernel/irq_32.c                        |   24 ++--
 arch/x86/kernel/irq_64.c                        |   35 +++---
 arch/x86/kernel/irqinit_64.c                    |   10 +-
 arch/x86/kernel/visws_quirks.c                  |   30 +++--
 arch/x86/mach-voyager/voyager_smp.c             |    4 +-
 arch/xtensa/kernel/irq.c                        |   10 +-
 drivers/gpio/gpiolib.c                          |    2 +-
 drivers/mfd/asic3.c                             |    4 +-
 drivers/mfd/htc-egpio.c                         |    2 +-
 drivers/parisc/dino.c                           |    6 +-
 drivers/parisc/eisa.c                           |    4 +-
 drivers/parisc/gsc.c                            |   12 ++-
 drivers/parisc/iosapic.c                        |    4 +-
 drivers/parisc/superio.c                        |    4 +-
 drivers/pcmcia/hd64465_ss.c                     |   12 ++-
 drivers/xen/events.c                            |    8 +-
 include/asm-ia64/hw_irq.h                       |    2 +-
 include/asm-mips/irq.h                          |    2 +-
 include/asm-powerpc/irq.h                       |    2 +-
 include/linux/irq.h                             |   34 ++++--
 kernel/irq/autoprobe.c                          |   10 +-
 kernel/irq/chip.c                               |   32 +++--
 kernel/irq/handle.c                             |  144 +++++++++++++++++++---
 kernel/irq/manage.c                             |   35 +++---
 kernel/irq/migration.c                          |   14 +-
 kernel/irq/proc.c                               |   36 +++---
 kernel/irq/resend.c                             |    2 +-
 kernel/irq/spurious.c                           |    5 +-
 133 files changed, 1271 insertions(+), 795 deletions(-)

diff --git a/arch/Kconfig b/arch/Kconfig
index c1f9feb..b367622 100644
--- a/arch/Kconfig
+++ b/arch/Kconfig
@@ -105,3 +105,7 @@ config HAVE_CLK
 
 config HAVE_DYN_ARRAY
 	def_bool n
+
+config HAVE_SPARSE_IRQ
+	def_bool n
+
diff --git a/arch/alpha/kernel/irq.c b/arch/alpha/kernel/irq.c
index c626a82..85d7173 100644
--- a/arch/alpha/kernel/irq.c
+++ b/arch/alpha/kernel/irq.c
@@ -46,16 +46,19 @@ int irq_select_affinity(unsigned int irq)
 {
 	static int last_cpu;
 	int cpu = last_cpu + 1;
+	struct irq_desc *desc;
 
-	if (!irq_desc[irq].chip->set_affinity || irq_user_affinity[irq])
+	desc = irq_desc(irq);
+
+	if (!desc->chip->set_affinity || irq_user_affinity[irq])
 		return 1;
 
 	while (!cpu_possible(cpu) || !cpu_isset(cpu, irq_default_affinity))
 		cpu = (cpu < (NR_CPUS-1) ? cpu + 1 : 0);
 	last_cpu = cpu;
 
-	irq_desc[irq].affinity = cpumask_of_cpu(cpu);
-	irq_desc[irq].chip->set_affinity(irq, cpumask_of_cpu(cpu));
+	desc->affinity = cpumask_of_cpu(cpu);
+	desc->chip->set_affinity(irq, cpumask_of_cpu(cpu));
 	return 0;
 }
 #endif /* CONFIG_SMP */
@@ -80,8 +83,10 @@ show_interrupts(struct seq_file *p, void *v)
 #endif
 
 	if (irq < ACTUAL_NR_IRQS) {
-		spin_lock_irqsave(&irq_desc[irq].lock, flags);
-		action = irq_desc[irq].action;
+		struct irq_desc *desc = irq_desc(irq);
+
+		spin_lock_irqsave(&desc->lock, flags);
+		action = desc->action;
 		if (!action) 
 			goto unlock;
 		seq_printf(p, "%3d: ", irq);
@@ -91,7 +96,7 @@ show_interrupts(struct seq_file *p, void *v)
 		for_each_online_cpu(j)
 			seq_printf(p, "%10u ", kstat_cpu(j).irqs[irq]);
 #endif
-		seq_printf(p, " %14s", irq_desc[irq].chip->typename);
+		seq_printf(p, " %14s", desc->chip->typename);
 		seq_printf(p, "  %c%s",
 			(action->flags & IRQF_DISABLED)?'+':' ',
 			action->name);
@@ -104,7 +109,7 @@ show_interrupts(struct seq_file *p, void *v)
 
 		seq_putc(p, '\n');
 unlock:
-		spin_unlock_irqrestore(&irq_desc[irq].lock, flags);
+		spin_unlock_irqrestore(&desc->lock, flags);
 	} else if (irq == ACTUAL_NR_IRQS) {
 #ifdef CONFIG_SMP
 		seq_puts(p, "IPI: ");
diff --git a/arch/alpha/kernel/irq_alpha.c b/arch/alpha/kernel/irq_alpha.c
index e16aeb6..feddec7 100644
--- a/arch/alpha/kernel/irq_alpha.c
+++ b/arch/alpha/kernel/irq_alpha.c
@@ -240,8 +240,9 @@ static struct hw_interrupt_type rtc_irq_type = {
 void __init
 init_rtc_irq(void)
 {
-	irq_desc[RTC_IRQ].status = IRQ_DISABLED;
-	irq_desc[RTC_IRQ].chip = &rtc_irq_type;
+	struct irq_desc *desc = irq_desc(RTC_IRQ);
+	desc->status = IRQ_DISABLED;
+	desc->chip = &rtc_irq_type;
 	setup_irq(RTC_IRQ, &timer_irqaction);
 }
 
diff --git a/arch/alpha/kernel/irq_i8259.c b/arch/alpha/kernel/irq_i8259.c
index 9405bee..39ba6f6 100644
--- a/arch/alpha/kernel/irq_i8259.c
+++ b/arch/alpha/kernel/irq_i8259.c
@@ -79,7 +79,7 @@ i8259a_startup_irq(unsigned int irq)
 void
 i8259a_end_irq(unsigned int irq)
 {
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		i8259a_enable_irq(irq);
 }
 
@@ -107,8 +107,10 @@ init_i8259a_irqs(void)
 	outb(0xff, 0xA1);	/* mask all of 8259A-2 */
 
 	for (i = 0; i < 16; i++) {
-		irq_desc[i].status = IRQ_DISABLED;
-		irq_desc[i].chip = &i8259a_irq_type;
+		struct irq_desc *desc;
+		desc = irq_desc(i);
+		desc->status = IRQ_DISABLED;
+		desc->chip = &i8259a_irq_type;
 	}
 
 	setup_irq(2, &cascade);
diff --git a/arch/alpha/kernel/irq_pyxis.c b/arch/alpha/kernel/irq_pyxis.c
index d53edbc..8fa2440 100644
--- a/arch/alpha/kernel/irq_pyxis.c
+++ b/arch/alpha/kernel/irq_pyxis.c
@@ -50,7 +50,7 @@ pyxis_startup_irq(unsigned int irq)
 static void
 pyxis_end_irq(unsigned int irq)
 {
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		pyxis_enable_irq(irq);
 }
 
@@ -117,10 +117,13 @@ init_pyxis_irqs(unsigned long ignore_mask)
 	*(vuip) CIA_IACK_SC;
 
 	for (i = 16; i < 48; ++i) {
+		struct irq_desc *desc;
+
 		if ((ignore_mask >> i) & 1)
 			continue;
-		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i].chip = &pyxis_irq_type;
+		desc = irq_desc(i);
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = &pyxis_irq_type;
 	}
 
 	setup_irq(16+7, &isa_cascade_irqaction);
diff --git a/arch/alpha/kernel/irq_srm.c b/arch/alpha/kernel/irq_srm.c
index 3221201..bceac72 100644
--- a/arch/alpha/kernel/irq_srm.c
+++ b/arch/alpha/kernel/irq_srm.c
@@ -43,7 +43,7 @@ srm_startup_irq(unsigned int irq)
 static void
 srm_end_irq(unsigned int irq)
 {
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		srm_enable_irq(irq);
 }
 
@@ -64,10 +64,13 @@ init_srm_irqs(long max, unsigned long ignore_mask)
 	long i;
 
 	for (i = 16; i < max; ++i) {
+		struct irq_desc *desc;
+
 		if (i < 64 && ((ignore_mask >> i) & 1))
 			continue;
-		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i].chip = &srm_irq_type;
+		desc = irq_desc(i);
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = &srm_irq_type;
 	}
 }
 
diff --git a/arch/alpha/kernel/sys_alcor.c b/arch/alpha/kernel/sys_alcor.c
index e53a1e1..31dab12 100644
--- a/arch/alpha/kernel/sys_alcor.c
+++ b/arch/alpha/kernel/sys_alcor.c
@@ -85,7 +85,7 @@ alcor_isa_mask_and_ack_irq(unsigned int irq)
 static void
 alcor_end_irq(unsigned int irq)
 {
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		alcor_enable_irq(irq);
 }
 
@@ -137,13 +137,16 @@ alcor_init_irq(void)
 	*(vuip)GRU_INT_CLEAR = 0; mb();			/* all clear */
 
 	for (i = 16; i < 48; ++i) {
+		struct irq_desc *desc;
+
 		/* On Alcor, at least, lines 20..30 are not connected
 		   and can generate spurious interrupts if we turn them
 		   on while IRQ probing.  */
 		if (i >= 16+20 && i <= 16+30)
 			continue;
-		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i].chip = &alcor_irq_type;
+		desc = irq_desc(i);
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = &alcor_irq_type;
 	}
 	i8259a_irq_type.ack = alcor_isa_mask_and_ack_irq;
 
diff --git a/arch/alpha/kernel/sys_cabriolet.c b/arch/alpha/kernel/sys_cabriolet.c
index ace475c..71c25d5 100644
--- a/arch/alpha/kernel/sys_cabriolet.c
+++ b/arch/alpha/kernel/sys_cabriolet.c
@@ -67,7 +67,7 @@ cabriolet_startup_irq(unsigned int irq)
 static void
 cabriolet_end_irq(unsigned int irq)
 { 
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		cabriolet_enable_irq(irq);
 }
 
@@ -122,8 +122,10 @@ common_init_irq(void (*srm_dev_int)(unsigned long v))
 		outb(0xff, 0x806);
 
 		for (i = 16; i < 35; ++i) {
-			irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-			irq_desc[i].chip = &cabriolet_irq_type;
+			struct irq_desc *desc = irq_desc(i);
+
+			desc->status = IRQ_DISABLED | IRQ_LEVEL;
+			desc->chip = &cabriolet_irq_type;
 		}
 	}
 
diff --git a/arch/alpha/kernel/sys_dp264.c b/arch/alpha/kernel/sys_dp264.c
index c71b0fd..5cbd892 100644
--- a/arch/alpha/kernel/sys_dp264.c
+++ b/arch/alpha/kernel/sys_dp264.c
@@ -125,7 +125,7 @@ dp264_startup_irq(unsigned int irq)
 static void
 dp264_end_irq(unsigned int irq)
 { 
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		dp264_enable_irq(irq);
 }
 
@@ -157,7 +157,7 @@ clipper_startup_irq(unsigned int irq)
 static void
 clipper_end_irq(unsigned int irq)
 { 
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		clipper_enable_irq(irq);
 }
 
@@ -298,8 +298,9 @@ init_tsunami_irqs(struct hw_interrupt_type * ops, int imin, int imax)
 {
 	long i;
 	for (i = imin; i <= imax; ++i) {
-		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i].chip = ops;
+		struct irq_desc *desc = irq_desc(i);
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = ops;
 	}
 }
 
diff --git a/arch/alpha/kernel/sys_eb64p.c b/arch/alpha/kernel/sys_eb64p.c
index 9c5a306..ca0b1ce 100644
--- a/arch/alpha/kernel/sys_eb64p.c
+++ b/arch/alpha/kernel/sys_eb64p.c
@@ -65,7 +65,7 @@ eb64p_startup_irq(unsigned int irq)
 static void
 eb64p_end_irq(unsigned int irq)
 {
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		eb64p_enable_irq(irq);
 }
 
@@ -135,8 +135,10 @@ eb64p_init_irq(void)
 	init_i8259a_irqs();
 
 	for (i = 16; i < 32; ++i) {
-		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i].chip = &eb64p_irq_type;
+		struct irq_desc *desc = irq_desc(i);
+
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = &eb64p_irq_type;
 	}		
 
 	common_init_isa_dma();
diff --git a/arch/alpha/kernel/sys_eiger.c b/arch/alpha/kernel/sys_eiger.c
index 7ef3b6f..48fc15c 100644
--- a/arch/alpha/kernel/sys_eiger.c
+++ b/arch/alpha/kernel/sys_eiger.c
@@ -76,7 +76,7 @@ eiger_startup_irq(unsigned int irq)
 static void
 eiger_end_irq(unsigned int irq)
 {
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		eiger_enable_irq(irq);
 }
 
@@ -153,8 +153,9 @@ eiger_init_irq(void)
 	init_i8259a_irqs();
 
 	for (i = 16; i < 128; ++i) {
-		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i].chip = &eiger_irq_type;
+		struct irq_desc *desc = irq_desc(i);
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = &eiger_irq_type;
 	}
 }
 
diff --git a/arch/alpha/kernel/sys_jensen.c b/arch/alpha/kernel/sys_jensen.c
index 2c3de97..1dda32e 100644
--- a/arch/alpha/kernel/sys_jensen.c
+++ b/arch/alpha/kernel/sys_jensen.c
@@ -68,13 +68,16 @@ jensen_local_startup(unsigned int irq)
 	/* the parport is really hw IRQ 1, silly Jensen.  */
 	if (irq == 7)
 		i8259a_startup_irq(1);
-	else
+	else {
+		struct irq_desc *desc = irq_desc(irq);
+
 		/*
 		 * For all true local interrupts, set the flag that prevents
 		 * the IPL from being dropped during handler processing.
 		 */
-		if (irq_desc[irq].action)
-			irq_desc[irq].action->flags |= IRQF_DISABLED;
+		if (desc->action)
+			desc->action->flags |= IRQF_DISABLED;
+	}
 	return 0;
 }
 
@@ -158,7 +161,7 @@ jensen_device_interrupt(unsigned long vector)
 	}
 
 	/* If there is no handler yet... */
-	if (irq_desc[irq].action == NULL) {
+	if (irq_desc(irq)->action == NULL) {
 	    /* If it is a local interrupt that cannot be masked... */
 	    if (vector >= 0x900)
 	    {
@@ -206,11 +209,11 @@ jensen_init_irq(void)
 {
 	init_i8259a_irqs();
 
-	irq_desc[1].chip = &jensen_local_irq_type;
-	irq_desc[4].chip = &jensen_local_irq_type;
-	irq_desc[3].chip = &jensen_local_irq_type;
-	irq_desc[7].chip = &jensen_local_irq_type;
-	irq_desc[9].chip = &jensen_local_irq_type;
+	irq_desc(1)->chip = &jensen_local_irq_type;
+	irq_desc(4)->chip = &jensen_local_irq_type;
+	irq_desc(3)->chip = &jensen_local_irq_type;
+	irq_desc(7)->chip = &jensen_local_irq_type;
+	irq_desc(9)->chip = &jensen_local_irq_type;
 
 	common_init_isa_dma();
 }
diff --git a/arch/alpha/kernel/sys_marvel.c b/arch/alpha/kernel/sys_marvel.c
index 828449c..ce0eb28 100644
--- a/arch/alpha/kernel/sys_marvel.c
+++ b/arch/alpha/kernel/sys_marvel.c
@@ -152,7 +152,7 @@ io7_startup_irq(unsigned int irq)
 static void
 io7_end_irq(unsigned int irq)
 {
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		io7_enable_irq(irq);
 }
 
@@ -303,8 +303,10 @@ init_io7_irqs(struct io7 *io7,
 
 	/* Set up the lsi irqs.  */
 	for (i = 0; i < 128; ++i) {
-		irq_desc[base + i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[base + i].chip = lsi_ops;
+		struct irq_desc *desc = irq_desc(base + i);
+
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = lsi_ops;
 	}
 
 	/* Disable the implemented irqs in hardware.  */
@@ -317,8 +319,10 @@ init_io7_irqs(struct io7 *io7,
 
 	/* Set up the msi irqs.  */
 	for (i = 128; i < (128 + 512); ++i) {
-		irq_desc[base + i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[base + i].chip = msi_ops;
+		struct irq_desc *desc = irq_desc(base + i);
+
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = msi_ops;
 	}
 
 	for (i = 0; i < 16; ++i)
@@ -335,8 +339,10 @@ marvel_init_irq(void)
 
 	/* Reserve the legacy irqs.  */
 	for (i = 0; i < 16; ++i) {
-		irq_desc[i].status = IRQ_DISABLED;
-		irq_desc[i].chip = &marvel_legacy_irq_type;
+		struct irq_desc *desc = irq_desc(i);
+
+		desc->status = IRQ_DISABLED;
+		desc->chip = &marvel_legacy_irq_type;
 	}
 
 	/* Init the io7 irqs.  */
diff --git a/arch/alpha/kernel/sys_mikasa.c b/arch/alpha/kernel/sys_mikasa.c
index 8d3e942..8499125 100644
--- a/arch/alpha/kernel/sys_mikasa.c
+++ b/arch/alpha/kernel/sys_mikasa.c
@@ -64,7 +64,7 @@ mikasa_startup_irq(unsigned int irq)
 static void
 mikasa_end_irq(unsigned int irq)
 {
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		mikasa_enable_irq(irq);
 }
 
@@ -115,8 +115,10 @@ mikasa_init_irq(void)
 	mikasa_update_irq_hw(0);
 
 	for (i = 16; i < 32; ++i) {
-		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i].chip = &mikasa_irq_type;
+		struct irq_desc *desc = irq_desc(i);
+
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = &mikasa_irq_type;
 	}
 
 	init_i8259a_irqs();
diff --git a/arch/alpha/kernel/sys_noritake.c b/arch/alpha/kernel/sys_noritake.c
index eb2a1d6..e4d975a 100644
--- a/arch/alpha/kernel/sys_noritake.c
+++ b/arch/alpha/kernel/sys_noritake.c
@@ -69,7 +69,7 @@ noritake_startup_irq(unsigned int irq)
 static void
 noritake_end_irq(unsigned int irq)
 {
-        if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+        if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
                 noritake_enable_irq(irq);
 }
 
@@ -144,8 +144,10 @@ noritake_init_irq(void)
 	outw(0, 0x54c);
 
 	for (i = 16; i < 48; ++i) {
-		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i].chip = &noritake_irq_type;
+		struct irq_desc *desc = irq_desc(i);
+
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = &noritake_irq_type;
 	}
 
 	init_i8259a_irqs();
diff --git a/arch/alpha/kernel/sys_rawhide.c b/arch/alpha/kernel/sys_rawhide.c
index 672cb2d..26b044c 100644
--- a/arch/alpha/kernel/sys_rawhide.c
+++ b/arch/alpha/kernel/sys_rawhide.c
@@ -131,7 +131,7 @@ rawhide_startup_irq(unsigned int irq)
 static void
 rawhide_end_irq(unsigned int irq)
 {
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		rawhide_enable_irq(irq);
 }
 
@@ -194,8 +194,10 @@ rawhide_init_irq(void)
 	}
 
 	for (i = 16; i < 128; ++i) {
-		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i].chip = &rawhide_irq_type;
+		struct irq_desc *desc = irq_desc(i);
+
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = &rawhide_irq_type;
 	}
 
 	init_i8259a_irqs();
diff --git a/arch/alpha/kernel/sys_rx164.c b/arch/alpha/kernel/sys_rx164.c
index ce1faa6..1956d74 100644
--- a/arch/alpha/kernel/sys_rx164.c
+++ b/arch/alpha/kernel/sys_rx164.c
@@ -68,7 +68,7 @@ rx164_startup_irq(unsigned int irq)
 static void
 rx164_end_irq(unsigned int irq)
 {
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		rx164_enable_irq(irq);
 }
 
@@ -116,8 +116,10 @@ rx164_init_irq(void)
 
 	rx164_update_irq_hw(0);
 	for (i = 16; i < 40; ++i) {
-		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i].chip = &rx164_irq_type;
+		struct irq_desc *desc = irq_desc(i);
+
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = &rx164_irq_type;
 	}
 
 	init_i8259a_irqs();
diff --git a/arch/alpha/kernel/sys_sable.c b/arch/alpha/kernel/sys_sable.c
index 99a7f19..5873ca1 100644
--- a/arch/alpha/kernel/sys_sable.c
+++ b/arch/alpha/kernel/sys_sable.c
@@ -484,7 +484,7 @@ sable_lynx_startup_irq(unsigned int irq)
 static void
 sable_lynx_end_irq(unsigned int irq)
 {
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		sable_lynx_enable_irq(irq);
 }
 
@@ -535,8 +535,10 @@ sable_lynx_init_irq(int nr_irqs)
 	long i;
 
 	for (i = 0; i < nr_irqs; ++i) {
-		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i].chip = &sable_lynx_irq_type;
+		struct irq_desc *desc = irq_desc(i);
+
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->hip = &sable_lynx_irq_type;
 	}
 
 	common_init_isa_dma();
diff --git a/arch/alpha/kernel/sys_takara.c b/arch/alpha/kernel/sys_takara.c
index 9bd9a31..9601b52 100644
--- a/arch/alpha/kernel/sys_takara.c
+++ b/arch/alpha/kernel/sys_takara.c
@@ -70,7 +70,7 @@ takara_startup_irq(unsigned int irq)
 static void
 takara_end_irq(unsigned int irq)
 {
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		takara_enable_irq(irq);
 }
 
@@ -153,8 +153,10 @@ takara_init_irq(void)
 		takara_update_irq_hw(i, -1);
 
 	for (i = 16; i < 128; ++i) {
-		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i].chip = &takara_irq_type;
+		struct irq_desc *desc = irq_desc(i);
+
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = &takara_irq_type;
 	}
 
 	common_init_isa_dma();
diff --git a/arch/alpha/kernel/sys_titan.c b/arch/alpha/kernel/sys_titan.c
index 52c91cc..9ee1a50 100644
--- a/arch/alpha/kernel/sys_titan.c
+++ b/arch/alpha/kernel/sys_titan.c
@@ -139,7 +139,7 @@ titan_startup_irq(unsigned int irq)
 static void
 titan_end_irq(unsigned int irq)
 {
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		titan_enable_irq(irq);
 }
 
@@ -187,8 +187,10 @@ init_titan_irqs(struct hw_interrupt_type * ops, int imin, int imax)
 {
 	long i;
 	for (i = imin; i <= imax; ++i) {
-		irq_desc[i].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i].chip = ops;
+		struct irq_desc *desc = irq_desc(i);
+
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = ops;
 	}
 }
 
diff --git a/arch/alpha/kernel/sys_wildfire.c b/arch/alpha/kernel/sys_wildfire.c
index 42c3eed..bdfbd41 100644
--- a/arch/alpha/kernel/sys_wildfire.c
+++ b/arch/alpha/kernel/sys_wildfire.c
@@ -150,10 +150,10 @@ static void
 wildfire_end_irq(unsigned int irq)
 { 
 #if 0
-	if (!irq_desc[irq].action)
+	if (!irq_desc(irq)->action)
 		printk("got irq %d\n", irq);
 #endif
-	if (!(irq_desc[irq].status & (IRQ_DISABLED|IRQ_INPROGRESS)))
+	if (!(irq_desc(irq)->status & (IRQ_DISABLED|IRQ_INPROGRESS)))
 		wildfire_enable_irq(irq);
 }
 
@@ -196,17 +196,20 @@ wildfire_init_irq_per_pca(int qbbno, int pcano)
 #endif
 
 	for (i = 0; i < 16; ++i) {
+		struct irq_desc *desc;
 		if (i == 2)
 			continue;
-		irq_desc[i+irq_bias].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i+irq_bias].chip = &wildfire_irq_type;
+		desc = irq_desc(i+irq_bias);
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		irq_desc->chip = &wildfire_irq_type;
 	}
 
-	irq_desc[36+irq_bias].status = IRQ_DISABLED | IRQ_LEVEL;
-	irq_desc[36+irq_bias].chip = &wildfire_irq_type;
+	irq_desc(36+irq_bias)->status = IRQ_DISABLED | IRQ_LEVEL;
+	irq_desc(36+irq_bias)->chip = &wildfire_irq_type;
 	for (i = 40; i < 64; ++i) {
-		irq_desc[i+irq_bias].status = IRQ_DISABLED | IRQ_LEVEL;
-		irq_desc[i+irq_bias].chip = &wildfire_irq_type;
+		struct irq_desc *desc = irq_desc(i+irq_bias);
+		desc->status = IRQ_DISABLED | IRQ_LEVEL;
+		desc->chip = &wildfire_irq_type;
 	}
 
 	setup_irq(32+irq_bias, &isa_enable);	
diff --git a/arch/arm/common/gic.c b/arch/arm/common/gic.c
index 0c89bd3..cf75345 100644
--- a/arch/arm/common/gic.c
+++ b/arch/arm/common/gic.c
@@ -117,7 +117,7 @@ static void gic_set_cpu(unsigned int irq, cpumask_t mask_val)
 	u32 val;
 
 	spin_lock(&irq_controller_lock);
-	irq_desc[irq].cpu = cpu;
+	irq_desc(irq)->cpu = cpu;
 	val = readl(reg) & ~(0xff << shift);
 	val |= 1 << (cpu + shift);
 	writel(val, reg);
diff --git a/arch/arm/kernel/irq.c b/arch/arm/kernel/irq.c
index 11dcd52..a542c8d 100644
--- a/arch/arm/kernel/irq.c
+++ b/arch/arm/kernel/irq.c
@@ -68,22 +68,24 @@ int show_interrupts(struct seq_file *p, void *v)
 	}
 
 	if (i < NR_IRQS) {
-		spin_lock_irqsave(&irq_desc[i].lock, flags);
-		action = irq_desc[i].action;
+		struct irq_desc *desc = irq_desc(i);
+
+		spin_lock_irqsave(&desc->lock, flags);
+		action = desc->action;
 		if (!action)
 			goto unlock;
 
 		seq_printf(p, "%3d: ", i);
 		for_each_present_cpu(cpu)
 			seq_printf(p, "%10u ", kstat_cpu(cpu).irqs[i]);
-		seq_printf(p, " %10s", irq_desc[i].chip->name ? : "-");
+		seq_printf(p, " %10s", desc->chip->name ? : "-");
 		seq_printf(p, "  %s", action->name);
 		for (action = action->next; action; action = action->next)
 			seq_printf(p, ", %s", action->name);
 
 		seq_putc(p, '\n');
 unlock:
-		spin_unlock_irqrestore(&irq_desc[i].lock, flags);
+		spin_unlock_irqrestore(&desc->lock, flags);
 	} else if (i == NR_IRQS) {
 #ifdef CONFIG_ARCH_ACORN
 		show_fiq_list(p, v);
@@ -158,7 +160,7 @@ void __init init_IRQ(void)
 	int irq;
 
 	for (irq = 0; irq < NR_IRQS; irq++)
-		irq_desc[irq].status |= IRQ_NOREQUEST | IRQ_NOPROBE;
+		irq_desc(irq)->status |= IRQ_NOREQUEST | IRQ_NOPROBE;
 
 #ifdef CONFIG_SMP
 	bad_irq_desc.affinity = CPU_MASK_ALL;
diff --git a/arch/arm/mach-at91/gpio.c b/arch/arm/mach-at91/gpio.c
index ee4964a..66db024 100644
--- a/arch/arm/mach-at91/gpio.c
+++ b/arch/arm/mach-at91/gpio.c
@@ -404,7 +404,7 @@ static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
 		}
 
 		pin = bank->chipbase;
-		gpio = &irq_desc[pin];
+		gpio = irq_desc(pin);
 
 		while (isr) {
 			if (isr & 1) {
@@ -515,7 +515,7 @@ void __init at91_gpio_irq_setup(void)
 		__raw_writel(~0, this->regbase + PIO_IDR);
 
 		for (i = 0, pin = this->chipbase; i < 32; i++, pin++) {
-			lockdep_set_class(&irq_desc[pin].lock, &gpio_lock_class);
+			lockdep_set_class(&irq_desc(pin)->lock, &gpio_lock_class);
 
 			/*
 			 * Can use the "simple" and not "edge" handler since it's
diff --git a/arch/arm/mach-davinci/gpio.c b/arch/arm/mach-davinci/gpio.c
index 9c67886..0eb53dc 100644
--- a/arch/arm/mach-davinci/gpio.c
+++ b/arch/arm/mach-davinci/gpio.c
@@ -155,10 +155,11 @@ static void gpio_irq_enable(unsigned irq)
 {
 	struct gpio_controller *__iomem g = get_irq_chip_data(irq);
 	u32 mask = __gpio_mask(irq_to_gpio(irq));
+	struct irq_desc *desc = irq_desc(irq);
 
-	if (irq_desc[irq].status & IRQ_TYPE_EDGE_FALLING)
+	if (desc->status & IRQ_TYPE_EDGE_FALLING)
 		__raw_writel(mask, &g->set_falling);
-	if (irq_desc[irq].status & IRQ_TYPE_EDGE_RISING)
+	if (desc->status & IRQ_TYPE_EDGE_RISING)
 		__raw_writel(mask, &g->set_rising);
 }
 
@@ -166,12 +167,14 @@ static int gpio_irq_type(unsigned irq, unsigned trigger)
 {
 	struct gpio_controller *__iomem g = get_irq_chip_data(irq);
 	u32 mask = __gpio_mask(irq_to_gpio(irq));
+	struct irq_desc *desc;
 
 	if (trigger & ~(IRQ_TYPE_EDGE_FALLING | IRQ_TYPE_EDGE_RISING))
 		return -EINVAL;
 
-	irq_desc[irq].status &= ~IRQ_TYPE_SENSE_MASK;
-	irq_desc[irq].status |= trigger;
+	desc = irq_desc(irq);
+	desc->status &= ~IRQ_TYPE_SENSE_MASK;
+	desc->status |= trigger;
 
 	__raw_writel(mask, (trigger & IRQ_TYPE_EDGE_FALLING)
 		     ? &g->set_falling : &g->clr_falling);
@@ -215,7 +218,7 @@ gpio_irq_handler(unsigned irq, struct irq_desc *desc)
 
 		/* now demux them to the right lowlevel handler */
 		n = (int)get_irq_data(irq);
-		gpio = &irq_desc[n];
+		gpio = irq_desc(n);
 		while (status) {
 			res = ffs(status);
 			n += res;
diff --git a/arch/arm/mach-ep93xx/core.c b/arch/arm/mach-ep93xx/core.c
index 5fed576..43fbb85 100644
--- a/arch/arm/mach-ep93xx/core.c
+++ b/arch/arm/mach-ep93xx/core.c
@@ -226,7 +226,7 @@ static void ep93xx_gpio_irq_ack(unsigned int irq)
 	int port = line >> 3;
 	int port_mask = 1 << (line & 7);
 
-	if ((irq_desc[irq].status & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH) {
+	if ((irq_desc(irq)->status & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH) {
 		gpio_int_type2[port] ^= port_mask; /* switch edge direction */
 		ep93xx_gpio_update_int_params(port);
 	}
@@ -240,7 +240,7 @@ static void ep93xx_gpio_irq_mask_ack(unsigned int irq)
 	int port = line >> 3;
 	int port_mask = 1 << (line & 7);
 
-	if ((irq_desc[irq].status & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH)
+	if ((irq_desc(irq)->status & IRQ_TYPE_SENSE_MASK) == IRQ_TYPE_EDGE_BOTH)
 		gpio_int_type2[port] ^= port_mask; /* switch edge direction */
 
 	gpio_int_unmasked[port] &= ~port_mask;
diff --git a/arch/arm/mach-orion5x/irq.c b/arch/arm/mach-orion5x/irq.c
index 9ae3f6d..9c087ad 100644
--- a/arch/arm/mach-orion5x/irq.c
+++ b/arch/arm/mach-orion5x/irq.c
@@ -47,7 +47,7 @@
 static void orion5x_gpio_irq_ack(u32 irq)
 {
 	int pin = irq_to_gpio(irq);
-	if (irq_desc[irq].status & IRQ_LEVEL)
+	if (irq_desc(irq)->status & IRQ_LEVEL)
 		/*
 		 * Mask bit for level interrupt
 		 */
@@ -62,7 +62,7 @@ static void orion5x_gpio_irq_ack(u32 irq)
 static void orion5x_gpio_irq_mask(u32 irq)
 {
 	int pin = irq_to_gpio(irq);
-	if (irq_desc[irq].status & IRQ_LEVEL)
+	if (irq_desc(irq)->status & IRQ_LEVEL)
 		orion5x_clrbits(GPIO_LEVEL_MASK, 1 << pin);
 	else
 		orion5x_clrbits(GPIO_EDGE_MASK, 1 << pin);
@@ -71,7 +71,7 @@ static void orion5x_gpio_irq_mask(u32 irq)
 static void orion5x_gpio_irq_unmask(u32 irq)
 {
 	int pin = irq_to_gpio(irq);
-	if (irq_desc[irq].status & IRQ_LEVEL)
+	if (irq_desc(irq)->status & IRQ_LEVEL)
 		orion5x_setbits(GPIO_LEVEL_MASK, 1 << pin);
 	else
 		orion5x_setbits(GPIO_EDGE_MASK, 1 << pin);
@@ -88,7 +88,7 @@ static int orion5x_gpio_set_irq_type(u32 irq, u32 type)
 		return -EINVAL;
 	}
 
-	desc = irq_desc + irq;
+	desc = irq_desc(irq);
 
 	switch (type) {
 	case IRQ_TYPE_LEVEL_HIGH:
diff --git a/arch/arm/mach-sa1100/h3600.c b/arch/arm/mach-sa1100/h3600.c
index b34ff42..08ace7e 100644
--- a/arch/arm/mach-sa1100/h3600.c
+++ b/arch/arm/mach-sa1100/h3600.c
@@ -822,15 +822,17 @@ static void __init h3800_init_irq(void)
 #if 0
 	for (i = 0; i < H3800_KPIO_IRQ_COUNT; i++) {
 		int irq = i + H3800_KPIO_IRQ_START;
-		irq_desc[irq].valid    = 1;
-		irq_desc[irq].probe_ok = 1;
+		struct irq_desc *desc = irq_desc(irq);
+		desc->valid    = 1;
+		desc->probe_ok = 1;
 		set_irq_chip(irq, &h3800_kpio_irqchip);
 	}
 
 	for (i = 0; i < H3800_GPIO_IRQ_COUNT; i++) {
 		int irq = i + H3800_GPIO_IRQ_START;
-		irq_desc[irq].valid    = 1;
-		irq_desc[irq].probe_ok = 1;
+		struct irq_desc *desc = irq_desc(irq);
+		desc->valid    = 1;
+		desc->probe_ok = 1;
 		set_irq_chip(irq, &h3800_gpio_irqchip);
 	}
 #endif
diff --git a/arch/arm/plat-mxc/gpio.c b/arch/arm/plat-mxc/gpio.c
index 318b268..17f8734 100644
--- a/arch/arm/plat-mxc/gpio.c
+++ b/arch/arm/plat-mxc/gpio.c
@@ -105,13 +105,14 @@ static void mxc_gpio_irq_handler(struct mxc_gpio_port *port, u32 irq_stat)
 
 	gpio_irq_no = port->virtual_irq_start;
 	for (; irq_stat != 0; irq_stat >>= 1, gpio_irq_no++) {
+		struct irq_desc *desc;
 
 		if ((irq_stat & 1) == 0)
 			continue;
 
-		BUG_ON(!(irq_desc[gpio_irq_no].handle_irq));
-		irq_desc[gpio_irq_no].handle_irq(gpio_irq_no,
-				&irq_desc[gpio_irq_no]);
+		desc = irq_desc(gpio_irq_no);
+		BUG_ON(!(desc->handle_irq));
+		desc->handle_irq(gpio_irq_no, desc);
 	}
 }
 
diff --git a/arch/arm/plat-omap/gpio.c b/arch/arm/plat-omap/gpio.c
index 63e0943..4e4ec0b 100644
--- a/arch/arm/plat-omap/gpio.c
+++ b/arch/arm/plat-omap/gpio.c
@@ -648,8 +648,10 @@ static int gpio_irq_type(unsigned irq, unsigned type)
 	spin_lock_irqsave(&bank->lock, flags);
 	retval = _set_gpio_triggering(bank, get_gpio_index(gpio), type);
 	if (retval == 0) {
-		irq_desc[irq].status &= ~IRQ_TYPE_SENSE_MASK;
-		irq_desc[irq].status |= type;
+		struct irq_desc *desc = irq_desc(irq);
+
+		desc->status &= ~IRQ_TYPE_SENSE_MASK;
+		desc->status |= type;
 	}
 	spin_unlock_irqrestore(&bank->lock, flags);
 
@@ -1503,7 +1505,7 @@ static int __init _omap_gpio_init(void)
 
 		for (j = bank->virtual_irq_start;
 		     j < bank->virtual_irq_start + gpio_count; j++) {
-			lockdep_set_class(&irq_desc[j].lock, &gpio_lock_class);
+			lockdep_set_class(&irq_desc(j)->lock, &gpio_lock_class);
 			set_irq_chip_data(j, bank);
 			if (bank_is_mpuio(bank))
 				set_irq_chip(j, &mpuio_irq_chip);
@@ -1818,7 +1820,7 @@ static int dbg_gpio_show(struct seq_file *s, void *unused)
 
 /* FIXME for at least omap2, show pullup/pulldown state */
 
-			irqstat = irq_desc[irq].status;
+			irqstat = irq_desc(irq)->status;
 			if (is_in && ((bank->suspend_wakeup & mask)
 					|| irqstat & IRQ_TYPE_SENSE_MASK)) {
 				char	*trigger = NULL;
diff --git a/arch/arm/plat-orion/irq.c b/arch/arm/plat-orion/irq.c
index fe66a18..01007f8 100644
--- a/arch/arm/plat-orion/irq.c
+++ b/arch/arm/plat-orion/irq.c
@@ -59,7 +59,7 @@ void __init orion_irq_init(unsigned int irq_start, void __iomem *maskaddr)
 		set_irq_chip(irq, &orion_irq_chip);
 		set_irq_chip_data(irq, maskaddr);
 		set_irq_handler(irq, handle_level_irq);
-		irq_desc[irq].status |= IRQ_LEVEL;
+		irq_desc(irq)->status |= IRQ_LEVEL;
 		set_irq_flags(irq, IRQF_VALID);
 	}
 }
diff --git a/arch/avr32/kernel/irq.c b/arch/avr32/kernel/irq.c
index a8e767d..28d5d03 100644
--- a/arch/avr32/kernel/irq.c
+++ b/arch/avr32/kernel/irq.c
@@ -51,22 +51,24 @@ int show_interrupts(struct seq_file *p, void *v)
 	}
 
 	if (i < NR_IRQS) {
-		spin_lock_irqsave(&irq_desc[i].lock, flags);
-		action = irq_desc[i].action;
+		struct irq_desc *desc = irq_desc(i);
+
+		spin_lock_irqsave(&desc->lock, flags);
+		action = desc->action;
 		if (!action)
 			goto unlock;
 
 		seq_printf(p, "%3d: ", i);
 		for_each_online_cpu(cpu)
 			seq_printf(p, "%10u ", kstat_cpu(cpu).irqs[i]);
-		seq_printf(p, " %8s", irq_desc[i].chip->name ? : "-");
+		seq_printf(p, " %8s", desc->chip->name ? : "-");
 		seq_printf(p, "  %s", action->name);
 		for (action = action->next; action; action = action->next)
 			seq_printf(p, ", %s", action->name);
 
 		seq_putc(p, '\n');
 	unlock:
-		spin_unlock_irqrestore(&irq_desc[i].lock, flags);
+		spin_unlock_irqrestore(&desc->lock, flags);
 	}
 
 	return 0;
diff --git a/arch/avr32/mach-at32ap/extint.c b/arch/avr32/mach-at32ap/extint.c
index c36a6d5..a98eb7a 100644
--- a/arch/avr32/mach-at32ap/extint.c
+++ b/arch/avr32/mach-at32ap/extint.c
@@ -88,7 +88,6 @@ static void eic_unmask_irq(unsigned int irq)
 static int eic_set_irq_type(unsigned int irq, unsigned int flow_type)
 {
 	struct eic *eic = get_irq_chip_data(irq);
-	struct irq_desc *desc;
 	unsigned int i = irq - eic->first_irq;
 	u32 mode, edge, level;
 	int ret = 0;
@@ -97,8 +96,6 @@ static int eic_set_irq_type(unsigned int irq, unsigned int flow_type)
 	if (flow_type == IRQ_TYPE_NONE)
 		flow_type = IRQ_TYPE_LEVEL_LOW;
 
-	desc = &irq_desc[irq];
-
 	mode = eic_readl(eic, MODE);
 	edge = eic_readl(eic, EDGE);
 	level = eic_readl(eic, LEVEL);
@@ -126,6 +123,10 @@ static int eic_set_irq_type(unsigned int irq, unsigned int flow_type)
 	}
 
 	if (ret == 0) {
+		struct irq_desc *desc;
+
+		desc = irq_desc(irq);
+
 		eic_writel(eic, MODE, mode);
 		eic_writel(eic, EDGE, edge);
 		eic_writel(eic, LEVEL, level);
diff --git a/arch/avr32/mach-at32ap/pio.c b/arch/avr32/mach-at32ap/pio.c
index 296294f..79bb503 100644
--- a/arch/avr32/mach-at32ap/pio.c
+++ b/arch/avr32/mach-at32ap/pio.c
@@ -262,7 +262,7 @@ static void gpio_irq_handler(unsigned irq, struct irq_desc *desc)
 			isr &= ~(1 << i);
 
 			i += gpio_irq;
-			d = &irq_desc[i];
+			d = irq_desc(i);
 
 			d->handle_irq(i, d);
 		} while (isr);
diff --git a/arch/blackfin/kernel/irqchip.c b/arch/blackfin/kernel/irqchip.c
index 07402f5..62b6caf 100644
--- a/arch/blackfin/kernel/irqchip.c
+++ b/arch/blackfin/kernel/irqchip.c
@@ -77,8 +77,10 @@ int show_interrupts(struct seq_file *p, void *v)
 	unsigned long flags;
 
 	if (i < NR_IRQS) {
-		spin_lock_irqsave(&irq_desc[i].lock, flags);
-		action = irq_desc[i].action;
+		struct irq_desc *desc = irq_desc(i);
+
+		spin_lock_irqsave(&desc->lock, flags);
+		action = desc->action;
 		if (!action)
 			goto unlock;
 
@@ -89,7 +91,7 @@ int show_interrupts(struct seq_file *p, void *v)
 
 		seq_putc(p, '\n');
  unlock:
-		spin_unlock_irqrestore(&irq_desc[i].lock, flags);
+		spin_unlock_irqrestore(&desc->lock, flags);
 	} else if (i == NR_IRQS) {
 		seq_printf(p, "Err: %10lu\n", irq_err_count);
 	}
diff --git a/arch/blackfin/kernel/traps.c b/arch/blackfin/kernel/traps.c
index ad922ab..28501eb 100644
--- a/arch/blackfin/kernel/traps.c
+++ b/arch/blackfin/kernel/traps.c
@@ -985,8 +985,10 @@ void show_regs(struct pt_regs *fp)
 	/* if no interrupts are going off, don't print this out */
 	if (fp->ipend & ~0x3F) {
 		for (i = 0; i < (NR_IRQS - 1); i++) {
-			spin_lock_irqsave(&irq_desc[i].lock, flags);
-			action = irq_desc[i].action;
+			struct irq_desc *desc = irq_desc(i);
+
+			spin_lock_irqsave(&desc->lock, flags);
+			action = desc->action;
 			if (!action)
 				goto unlock;
 
@@ -998,7 +1000,7 @@ void show_regs(struct pt_regs *fp)
 			}
 			printk("\n");
 unlock:
-			spin_unlock_irqrestore(&irq_desc[i].lock, flags);
+			spin_unlock_irqrestore(&desc->lock, flags);
 		}
 	}
 
diff --git a/arch/blackfin/mach-bf527/boards/cm_bf527.c b/arch/blackfin/mach-bf527/boards/cm_bf527.c
index 0b26ae2..08ad8ad 100644
--- a/arch/blackfin/mach-bf527/boards/cm_bf527.c
+++ b/arch/blackfin/mach-bf527/boards/cm_bf527.c
@@ -989,7 +989,7 @@ static int __init stamp_init(void)
 	spi_register_board_info(bfin_spi_board_info, ARRAY_SIZE(bfin_spi_board_info));
 
 #if defined(CONFIG_PATA_PLATFORM) || defined(CONFIG_PATA_PLATFORM_MODULE)
-	irq_desc[PATA_INT].status |= IRQ_NOAUTOEN;
+	irq_desc(PATA_INT)->status |= IRQ_NOAUTOEN;
 #endif
 	return 0;
 }
diff --git a/arch/blackfin/mach-bf527/boards/ezkit.c b/arch/blackfin/mach-bf527/boards/ezkit.c
index 689b69c..66e770d 100644
--- a/arch/blackfin/mach-bf527/boards/ezkit.c
+++ b/arch/blackfin/mach-bf527/boards/ezkit.c
@@ -1024,7 +1024,7 @@ static int __init stamp_init(void)
 	spi_register_board_info(bfin_spi_board_info, ARRAY_SIZE(bfin_spi_board_info));
 
 #if defined(CONFIG_PATA_PLATFORM) || defined(CONFIG_PATA_PLATFORM_MODULE)
-	irq_desc[PATA_INT].status |= IRQ_NOAUTOEN;
+	irq_desc(PATA_INT)->status |= IRQ_NOAUTOEN;
 #endif
 	return 0;
 }
diff --git a/arch/blackfin/mach-bf533/boards/cm_bf533.c b/arch/blackfin/mach-bf533/boards/cm_bf533.c
index ed2b0b8..49b02ec 100644
--- a/arch/blackfin/mach-bf533/boards/cm_bf533.c
+++ b/arch/blackfin/mach-bf533/boards/cm_bf533.c
@@ -418,7 +418,7 @@ static int __init cm_bf533_init(void)
 #endif
 
 #if defined(CONFIG_PATA_PLATFORM) || defined(CONFIG_PATA_PLATFORM_MODULE)
-	irq_desc[PATA_INT].status |= IRQ_NOAUTOEN;
+	irq_desc(PATA_INT)->status |= IRQ_NOAUTOEN;
 #endif
 	return 0;
 }
diff --git a/arch/blackfin/mach-bf533/boards/ezkit.c b/arch/blackfin/mach-bf533/boards/ezkit.c
index 079389c..0b9c3a6 100644
--- a/arch/blackfin/mach-bf533/boards/ezkit.c
+++ b/arch/blackfin/mach-bf533/boards/ezkit.c
@@ -426,7 +426,7 @@ static int __init ezkit_init(void)
 	spi_register_board_info(bfin_spi_board_info, ARRAY_SIZE(bfin_spi_board_info));
 
 #if defined(CONFIG_PATA_PLATFORM) || defined(CONFIG_PATA_PLATFORM_MODULE)
-	irq_desc[PATA_INT].status |= IRQ_NOAUTOEN;
+	irq_desc(PATA_INT)->status |= IRQ_NOAUTOEN;
 #endif
 	return 0;
 }
diff --git a/arch/blackfin/mach-bf533/boards/stamp.c b/arch/blackfin/mach-bf533/boards/stamp.c
index 13ae495..1bb6d18 100644
--- a/arch/blackfin/mach-bf533/boards/stamp.c
+++ b/arch/blackfin/mach-bf533/boards/stamp.c
@@ -627,7 +627,7 @@ static int __init stamp_init(void)
 	spi_register_board_info(bfin_spi_board_info, ARRAY_SIZE(bfin_spi_board_info));
 
 #if defined(CONFIG_PATA_PLATFORM) || defined(CONFIG_PATA_PLATFORM_MODULE)
-	irq_desc[PATA_INT].status |= IRQ_NOAUTOEN;
+	irq_desc(PATA_INT)->status |= IRQ_NOAUTOEN;
 #endif
 	return 0;
 }
diff --git a/arch/blackfin/mach-bf537/boards/cm_bf537.c b/arch/blackfin/mach-bf537/boards/cm_bf537.c
index 73f2142..999af68 100644
--- a/arch/blackfin/mach-bf537/boards/cm_bf537.c
+++ b/arch/blackfin/mach-bf537/boards/cm_bf537.c
@@ -521,7 +521,7 @@ static int __init cm_bf537_init(void)
 #endif
 
 #if defined(CONFIG_PATA_PLATFORM) || defined(CONFIG_PATA_PLATFORM_MODULE)
-	irq_desc[PATA_INT].status |= IRQ_NOAUTOEN;
+	irq_desc(PATA_INT)->status |= IRQ_NOAUTOEN;
 #endif
 	return 0;
 }
diff --git a/arch/blackfin/mach-bf537/boards/generic_board.c b/arch/blackfin/mach-bf537/boards/generic_board.c
index 01b63e2..6f57f09 100644
--- a/arch/blackfin/mach-bf537/boards/generic_board.c
+++ b/arch/blackfin/mach-bf537/boards/generic_board.c
@@ -733,7 +733,7 @@ static int __init stamp_init(void)
 #endif
 
 #if defined(CONFIG_PATA_PLATFORM) || defined(CONFIG_PATA_PLATFORM_MODULE)
-	irq_desc[PATA_INT].status |= IRQ_NOAUTOEN;
+	irq_desc(PATA_INT)->status |= IRQ_NOAUTOEN;
 #endif
 	return 0;
 }
diff --git a/arch/blackfin/mach-bf537/boards/stamp.c b/arch/blackfin/mach-bf537/boards/stamp.c
index 6dbc76f..555b68f 100644
--- a/arch/blackfin/mach-bf537/boards/stamp.c
+++ b/arch/blackfin/mach-bf537/boards/stamp.c
@@ -1026,7 +1026,7 @@ static int __init stamp_init(void)
 	spi_register_board_info(bfin_spi_board_info, ARRAY_SIZE(bfin_spi_board_info));
 
 #if defined(CONFIG_PATA_PLATFORM) || defined(CONFIG_PATA_PLATFORM_MODULE)
-	irq_desc[PATA_INT].status |= IRQ_NOAUTOEN;
+	irq_desc(PATA_INT)->status |= IRQ_NOAUTOEN;
 #endif
 
 	return 0;
diff --git a/arch/blackfin/mach-bf561/boards/cm_bf561.c b/arch/blackfin/mach-bf561/boards/cm_bf561.c
index 466ef59..54ce4cc 100644
--- a/arch/blackfin/mach-bf561/boards/cm_bf561.c
+++ b/arch/blackfin/mach-bf561/boards/cm_bf561.c
@@ -411,7 +411,7 @@ static int __init cm_bf561_init(void)
 #endif
 
 #if defined(CONFIG_PATA_PLATFORM) || defined(CONFIG_PATA_PLATFORM_MODULE)
-	irq_desc[PATA_INT].status |= IRQ_NOAUTOEN;
+	irq_desc(PATA_INT)->status |= IRQ_NOAUTOEN;
 #endif
 	return 0;
 }
diff --git a/arch/blackfin/mach-bf561/boards/ezkit.c b/arch/blackfin/mach-bf561/boards/ezkit.c
index bc6fede..8cdc0ad 100644
--- a/arch/blackfin/mach-bf561/boards/ezkit.c
+++ b/arch/blackfin/mach-bf561/boards/ezkit.c
@@ -540,7 +540,7 @@ static int __init ezkit_init(void)
 	spi_register_board_info(bfin_spi_board_info, ARRAY_SIZE(bfin_spi_board_info));
 
 #if defined(CONFIG_PATA_PLATFORM) || defined(CONFIG_PATA_PLATFORM_MODULE)
-	irq_desc[PATA_INT].status |= IRQ_NOAUTOEN;
+	irq_desc(PATA_INT)->status |= IRQ_NOAUTOEN;
 #endif
 	return 0;
 }
diff --git a/arch/cris/arch-v10/kernel/irq.c b/arch/cris/arch-v10/kernel/irq.c
index 65ed803..a5e6e8c 100644
--- a/arch/cris/arch-v10/kernel/irq.c
+++ b/arch/cris/arch-v10/kernel/irq.c
@@ -221,7 +221,7 @@ init_IRQ(void)
 
 	/* Initialize IRQ handler descriptors. */
 	for(i = 2; i < NR_IRQS; i++) {
-		irq_desc[i].chip = &crisv10_irq_type;
+		irq_desc(i)->chip = &crisv10_irq_type;
 		set_int_vector(i, interrupt[i]);
 	}
 
diff --git a/arch/cris/arch-v32/kernel/irq.c b/arch/cris/arch-v32/kernel/irq.c
index 173c141..5b45bac 100644
--- a/arch/cris/arch-v32/kernel/irq.c
+++ b/arch/cris/arch-v32/kernel/irq.c
@@ -475,15 +475,15 @@ init_IRQ(void)
 
 	/* Point all IRQ's to bad handlers. */
 	for (i = FIRST_IRQ, j = 0; j < NR_IRQS; i++, j++) {
-		irq_desc[j].chip = &crisv32_irq_type;
+		irq_desc(j)->chip = &crisv32_irq_type;
 		set_exception_vector(i, interrupt[j]);
 	}
 
         /* Mark Timer and IPI IRQs as CPU local */
 	irq_allocations[TIMER0_INTR_VECT - FIRST_IRQ].cpu = CPU_FIXED;
-	irq_desc[TIMER0_INTR_VECT].status |= IRQ_PER_CPU;
+	irq_desc(TIMER0_INTR_VECT)->status |= IRQ_PER_CPU;
 	irq_allocations[IPI_INTR_VECT - FIRST_IRQ].cpu = CPU_FIXED;
-	irq_desc[IPI_INTR_VECT].status |= IRQ_PER_CPU;
+	irq_desc(IPI_INTR_VECT)->status |= IRQ_PER_CPU;
 
 	set_exception_vector(0x00, nmi_interrupt);
 	set_exception_vector(0x30, multiple_interrupt);
diff --git a/arch/cris/kernel/irq.c b/arch/cris/kernel/irq.c
index 2dfac8c..b280e0a 100644
--- a/arch/cris/kernel/irq.c
+++ b/arch/cris/kernel/irq.c
@@ -57,8 +57,10 @@ int show_interrupts(struct seq_file *p, void *v)
 	}
 
 	if (i < NR_IRQS) {
-		spin_lock_irqsave(&irq_desc[i].lock, flags);
-		action = irq_desc[i].action;
+		struct irq_desc *desc = irq_desc(i);
+
+		spin_lock_irqsave(&desc->lock, flags);
+		action = desc->action;
 		if (!action)
 			goto skip;
 		seq_printf(p, "%3d: ",i);
@@ -68,7 +70,7 @@ int show_interrupts(struct seq_file *p, void *v)
 		for_each_online_cpu(j)
 			seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
 #endif
-		seq_printf(p, " %14s", irq_desc[i].chip->typename);
+		seq_printf(p, " %14s", desc->chip->typename);
 		seq_printf(p, "  %s", action->name);
 
 		for (action=action->next; action; action = action->next)
@@ -76,7 +78,7 @@ int show_interrupts(struct seq_file *p, void *v)
 
 		seq_putc(p, '\n');
 skip:
-		spin_unlock_irqrestore(&irq_desc[i].lock, flags);
+		spin_unlock_irqrestore(&desc->lock, flags);
 	}
 	return 0;
 }
diff --git a/arch/frv/kernel/irq.c b/arch/frv/kernel/irq.c
index 73abae7..4770219 100644
--- a/arch/frv/kernel/irq.c
+++ b/arch/frv/kernel/irq.c
@@ -69,13 +69,15 @@ int show_interrupts(struct seq_file *p, void *v)
 	}
 
 	if (i < NR_IRQS) {
-		spin_lock_irqsave(&irq_desc[i].lock, flags);
-		action = irq_desc[i].action;
+		struct irq_desc *desc = irq_desc(i);
+
+		spin_lock_irqsave(&desc->lock, flags);
+		action = desc->action;
 		if (action) {
 			seq_printf(p, "%3d: ", i);
 			for_each_present_cpu(cpu)
 				seq_printf(p, "%10u ", kstat_cpu(cpu).irqs[i]);
-			seq_printf(p, " %10s", irq_desc[i].chip->name ? : "-");
+			seq_printf(p, " %10s", desc->chip->name ? : "-");
 			seq_printf(p, "  %s", action->name);
 			for (action = action->next;
 			     action;
@@ -85,7 +87,7 @@ int show_interrupts(struct seq_file *p, void *v)
 			seq_putc(p, '\n');
 		}
 
-		spin_unlock_irqrestore(&irq_desc[i].lock, flags);
+		spin_unlock_irqrestore(&desc->lock, flags);
 	} else if (i == NR_IRQS) {
 		seq_printf(p, "Err: %10u\n", atomic_read(&irq_err_count));
 	}
diff --git a/arch/h8300/kernel/irq.c b/arch/h8300/kernel/irq.c
index ef4f004..6c2e213 100644
--- a/arch/h8300/kernel/irq.c
+++ b/arch/h8300/kernel/irq.c
@@ -166,10 +166,12 @@ void __init init_IRQ(void)
 	setup_vector();
 
 	for (c = 0; c < NR_IRQS; c++) {
-		irq_desc[c].status = IRQ_DISABLED;
-		irq_desc[c].action = NULL;
-		irq_desc[c].depth = 1;
-		irq_desc[c].chip = &h8300irq_chip;
+		struct irq_desc *desc = irq_desc(c);
+
+		desc->status = IRQ_DISABLED;
+		desc->action = NULL;
+		desc->depth = 1;
+		desc->chip = &h8300irq_chip;
 	}
 }
 
@@ -191,21 +193,23 @@ int show_interrupts(struct seq_file *p, void *v)
 		seq_puts(p, "           CPU0");
 
 	if (i < NR_IRQS) {
-		spin_lock_irqsave(&irq_desc[i].lock, flags);
-		action = irq_desc[i].action;
+		struct irq_desc *desc = irq_desc(i);
+
+		spin_lock_irqsave(&desc->lock, flags);
+		action = desc->action;
 		if (!action)
 			goto unlock;
 		seq_printf(p, "%3d: ",i);
 		seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
-		seq_printf(p, " %14s", irq_desc[i].chip->name);
-		seq_printf(p, "-%-8s", irq_desc[i].name);
+		seq_printf(p, " %14s", desc->chip->name);
+		seq_printf(p, "-%-8s", desc->name);
 		seq_printf(p, "  %s", action->name);
 
 		for (action=action->next; action; action = action->next)
 			seq_printf(p, ", %s", action->name);
 		seq_putc(p, '\n');
 unlock:
-		spin_unlock_irqrestore(&irq_desc[i].lock, flags);
+		spin_unlock_irqrestore(&desc->lock, flags);
 	}
 	return 0;
 }
diff --git a/arch/ia64/kernel/iosapic.c b/arch/ia64/kernel/iosapic.c
index 3bc2fa6..d373290 100644
--- a/arch/ia64/kernel/iosapic.c
+++ b/arch/ia64/kernel/iosapic.c
@@ -398,7 +398,7 @@ iosapic_end_level_irq (unsigned int irq)
 	int do_unmask_irq = 0;
 
 	irq_complete_move(irq);
-	if (unlikely(irq_desc[irq].status & IRQ_MOVE_PENDING)) {
+	if (unlikely(irq_desc(irq)->status & IRQ_MOVE_PENDING)) {
 		do_unmask_irq = 1;
 		mask_irq(irq);
 	}
@@ -765,6 +765,7 @@ iosapic_register_intr (unsigned int gsi,
 	struct iosapic_rte_info *rte;
 	u32 low32;
 	unsigned char dmode;
+	struct irq_desc *desc;
 
 	/*
 	 * If this GSI has already been registered (i.e., it's a
@@ -792,12 +793,14 @@ iosapic_register_intr (unsigned int gsi,
 			goto unlock_iosapic_lock;
 	}
 
-	spin_lock(&irq_desc[irq].lock);
+	desc = irq_desc(irq);
+
+	spin_lock(&desc->lock);
 	dest = get_target_cpu(gsi, irq);
 	dmode = choose_dmode();
 	err = register_intr(gsi, irq, dmode, polarity, trigger);
 	if (err < 0) {
-		spin_unlock(&irq_desc[irq].lock);
+		spin_unlock(&desc->lock);
 		irq = err;
 		goto unlock_iosapic_lock;
 	}
@@ -816,7 +819,7 @@ iosapic_register_intr (unsigned int gsi,
 	       (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
 	       cpu_logical_id(dest), dest, irq_to_vector(irq));
 
-	spin_unlock(&irq_desc[irq].lock);
+	spin_unlock(&desc->lock);
  unlock_iosapic_lock:
 	spin_unlock_irqrestore(&iosapic_lock, flags);
 	return irq;
diff --git a/arch/ia64/kernel/irq.c b/arch/ia64/kernel/irq.c
index 7fd18f5..b9290c6 100644
--- a/arch/ia64/kernel/irq.c
+++ b/arch/ia64/kernel/irq.c
@@ -71,8 +71,10 @@ int show_interrupts(struct seq_file *p, void *v)
 	}
 
 	if (i < NR_IRQS) {
-		spin_lock_irqsave(&irq_desc[i].lock, flags);
-		action = irq_desc[i].action;
+		struct irq_desc *desc = irq_desc(i);
+
+		spin_lock_irqsave(&desc->lock, flags);
+		action = desc->action;
 		if (!action)
 			goto skip;
 		seq_printf(p, "%3d: ",i);
@@ -83,7 +85,7 @@ int show_interrupts(struct seq_file *p, void *v)
 			seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
 		}
 #endif
-		seq_printf(p, " %14s", irq_desc[i].chip->name);
+		seq_printf(p, " %14s", desc->chip->name);
 		seq_printf(p, "  %s", action->name);
 
 		for (action=action->next; action; action = action->next)
@@ -91,7 +93,7 @@ int show_interrupts(struct seq_file *p, void *v)
 
 		seq_putc(p, '\n');
 skip:
-		spin_unlock_irqrestore(&irq_desc[i].lock, flags);
+		spin_unlock_irqrestore(&desc->lock, flags);
 	} else if (i == NR_IRQS)
 		seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
 	return 0;
@@ -107,7 +109,7 @@ void set_irq_affinity_info (unsigned int irq, int hwid, int redir)
 	cpu_set(cpu_logical_id(hwid), mask);
 
 	if (irq < NR_IRQS) {
-		irq_desc[irq].affinity = mask;
+		irq_desc(irq)->affinity = mask;
 		irq_redir[irq] = (char) (redir & 0xff);
 	}
 }
@@ -138,7 +140,7 @@ static void migrate_irqs(void)
 	int 		irq, new_cpu;
 
 	for (irq=0; irq < NR_IRQS; irq++) {
-		desc = irq_desc + irq;
+		desc = irq_desc(irq);
 
 		if (desc->status == IRQ_DISABLED)
 			continue;
@@ -152,7 +154,7 @@ static void migrate_irqs(void)
 		if (desc->status == IRQ_PER_CPU)
 			continue;
 
-		cpus_and(mask, irq_desc[irq].affinity, cpu_online_map);
+		cpus_and(mask, desc->affinity, cpu_online_map);
 		if (any_online_cpu(mask) == NR_CPUS) {
 			/*
 			 * Save it for phase 2 processing
diff --git a/arch/ia64/kernel/msi_ia64.c b/arch/ia64/kernel/msi_ia64.c
index 60c6ef6..8199eb2 100644
--- a/arch/ia64/kernel/msi_ia64.c
+++ b/arch/ia64/kernel/msi_ia64.c
@@ -73,7 +73,7 @@ static void ia64_set_msi_irq_affinity(unsigned int irq, cpumask_t cpu_mask)
 	msg.data = data;
 
 	write_msi_msg(irq, &msg);
-	irq_desc[irq].affinity = cpumask_of_cpu(cpu);
+	irq_desc(irq)->affinity = cpumask_of_cpu(cpu);
 }
 #endif /* CONFIG_SMP */
 
diff --git a/arch/ia64/sn/kernel/irq.c b/arch/ia64/sn/kernel/irq.c
index 96c31b4..98d4d83 100644
--- a/arch/ia64/sn/kernel/irq.c
+++ b/arch/ia64/sn/kernel/irq.c
@@ -429,7 +429,7 @@ sn_call_force_intr_provider(struct sn_irq_info *sn_irq_info)
 	pci_provider = sn_pci_provider[sn_irq_info->irq_bridge_type];
 
 	/* Don't force an interrupt if the irq has been disabled */
-	if (!(irq_desc[sn_irq_info->irq_irq].status & IRQ_DISABLED) &&
+	if (!(irq_desc(sn_irq_info->irq_irq)->status & IRQ_DISABLED) &&
 	    pci_provider && pci_provider->force_interrupt)
 		(*pci_provider->force_interrupt)(sn_irq_info);
 }
diff --git a/arch/ia64/sn/kernel/msi_sn.c b/arch/ia64/sn/kernel/msi_sn.c
index 83f190f..51f66d8 100644
--- a/arch/ia64/sn/kernel/msi_sn.c
+++ b/arch/ia64/sn/kernel/msi_sn.c
@@ -204,7 +204,7 @@ static void sn_set_msi_irq_affinity(unsigned int irq, cpumask_t cpu_mask)
 	msg.address_lo = (u32)(bus_addr & 0x00000000ffffffff);
 
 	write_msi_msg(irq, &msg);
-	irq_desc[irq].affinity = cpu_mask;
+	irq_desc(irq)->affinity = cpu_mask;
 }
 #endif /* CONFIG_SMP */
 
diff --git a/arch/m32r/kernel/irq.c b/arch/m32r/kernel/irq.c
index d0c5b0b..d9c2a00 100644
--- a/arch/m32r/kernel/irq.c
+++ b/arch/m32r/kernel/irq.c
@@ -43,8 +43,10 @@ int show_interrupts(struct seq_file *p, void *v)
 	}
 
 	if (i < NR_IRQS) {
-		spin_lock_irqsave(&irq_desc[i].lock, flags);
-		action = irq_desc[i].action;
+		struct irq_desc *desc = irq_desc(i);
+
+		spin_lock_irqsave(&desc->lock, flags);
+		action = desc->action;
 		if (!action)
 			goto skip;
 		seq_printf(p, "%3d: ",i);
@@ -54,7 +56,7 @@ int show_interrupts(struct seq_file *p, void *v)
 		for_each_online_cpu(j)
 			seq_printf(p, "%10u ", kstat_cpu(j).irqs[i]);
 #endif
-		seq_printf(p, " %14s", irq_desc[i].chip->typename);
+		seq_printf(p, " %14s", desc->chip->typename);
 		seq_printf(p, "  %s", action->name);
 
 		for (action=action->next; action; action = action->next)
@@ -62,7 +64,7 @@ int show_interrupts(struct seq_file *p, void *v)
 
 		seq_putc(p, '\n');
 skip:
-		spin_unlock_irqrestore(&irq_desc[i].lock, flags);
+		spin_unlock_irqrestore(&desc->lock, flags);
 	} else if (i == NR_IRQS) {
 		seq_printf(p, "ERR: %10u\n", atomic_read(&irq_err_count));
 		seq_printf(p, "MIS: %10u\n", atomic_read(&irq_mis_count));
diff --git a/arch/m32r/platforms/m32104ut/setup.c b/arch/m32r/platforms/m32104ut/setup.c
index 98138b4..b923269 100644
--- a/arch/m32r/platforms/m32104ut/setup.c
+++ b/arch/m32r/platforms/m32104ut/setup.c
@@ -77,6 +77,7 @@ static struct hw_interrupt_type m32104ut_irq_type =
 void __init init_IRQ(void)
 {
 	static int once = 0;
+	struct irq_desc *desc;
 
 	if (once)
 		return;
@@ -85,36 +86,40 @@ void __init init_IRQ(void)
 
 #if defined(CONFIG_SMC91X)
 	/* INT#0: LAN controller on M32104UT-LAN (SMC91C111)*/
-	irq_desc[M32R_IRQ_INT0].status = IRQ_DISABLED;
-	irq_desc[M32R_IRQ_INT0].chip = &m32104ut_irq_type;
-	irq_desc[M32R_IRQ_INT0].action = 0;
-	irq_desc[M32R_IRQ_INT0].depth = 1;
+	desc = irq_desc(M32R_IRQ_INT0);
+	desc->status = IRQ_DISABLED;
+	desc->chip = &m32104ut_irq_type;
+	desc->action = 0;
+	desc->depth = 1;
 	icu_data[M32R_IRQ_INT0].icucr = M32R_ICUCR_IEN | M32R_ICUCR_ISMOD11; /* "H" level sense */
 	disable_m32104ut_irq(M32R_IRQ_INT0);
 #endif  /* CONFIG_SMC91X */
 
 	/* MFT2 : system timer */
-	irq_desc[M32R_IRQ_MFT2].status = IRQ_DISABLED;
-	irq_desc[M32R_IRQ_MFT2].chip = &m32104ut_irq_type;
-	irq_desc[M32R_IRQ_MFT2].action = 0;
-	irq_desc[M32R_IRQ_MFT2].depth = 1;
+	desc = irq_desc(M32R_IRQ_MFT2);
+	desc->status = IRQ_DISABLED;
+	desc->chip = &m32104ut_irq_type;
+	desc->action = 0;
+	desc->depth = 1;
 	icu_data[M32R_IRQ_MFT2].icucr = M32R_ICUCR_IEN;
 	disable_m32104ut_irq(M32R_IRQ_MFT2);
 
 #ifdef CONFIG_SERIAL_M32R_SIO
 	/* SIO0_R : uart receive data */
-	irq_desc[M32R_IRQ_SIO0_R].status = IRQ_DISABLED;
-	irq_desc[M32R_IRQ_SIO0_R].chip = &m32104ut_irq_type;
-	irq_desc[M32R_IRQ_SIO0_R].action = 0;
-	irq_desc[M32R_IRQ_SIO0_R].depth = 1;
+	desc = irq_desc(M32R_IRQ_SIO0_R);
+	desc->status = IRQ_DISABLED;
+	desc->chip = &m32104ut_irq_type;
+	desc->action = 0;
+	desc->depth = 1;
 	icu_data[M32R_IRQ_SIO0_R].icucr = M32R_ICUCR_IEN;
 	disable_m32104ut_irq(M32R_IRQ_SIO0_R);
 
 	/* SIO0_S : uart send data */
-	irq_desc[M32R_IRQ_SIO0_S].status = IRQ_DISABLED;
-	irq_desc[M32R_IRQ_SIO0_S].chip = &m32104ut_irq_type;
-	irq_desc[M32R_IRQ_SIO0_S].action = 0;
-	irq_desc[M32R_IRQ_SIO0_S].depth = 1;
+	desc = irq_desc(M32R_IRQ_SIO0_S);
+	desc->status = IRQ_DISABLED;
+	desc->chip = &m32104ut_irq_type;
+	desc->action = 0;
+	desc->depth = 1;
 	icu_data[M32R_IRQ_SIO0_S].icucr = M32R_ICUCR_IEN;
 	disable_m32104ut_irq(M32R_IRQ_SIO0_S);
 #endif /* CONFIG_SERIAL_M32R_SIO */
diff --git a/arch/m32r/platforms/m32700ut/setup.c b/arch/m32r/platforms/m32700ut/setup.c
index 77b0ae9..c82e44d 100644
--- a/arch/m32r/platforms/m32700ut/setup.c
+++ b/arch/m32r/platforms/m32700ut/setup.c
@@ -297,103 +297,117 @@ static struct hw_interrupt_type m32700ut_lcdpld_irq_type =
 
 void __init init_IRQ(void)
 {
+	struct irq_desc *desc;
+
 #if defined(CONFIG_SMC91X)
 	/* INT#0: LAN controller on M32700UT-LAN (SMC91C111)*/
-	irq_desc[M32700UT_LAN_IRQ_LAN].status = IRQ_DISABLED;
-	irq_desc[M32700UT_LAN_IRQ_LAN].chip = &m32700ut_lanpld_irq_type;
-	irq_desc[M32700UT_LAN_IRQ_LAN].action = 0;
-	irq_desc[M32700UT_LAN_IRQ_LAN].depth = 1;	/* disable nested irq */
+	desc = irq_desc(M32700UT_LAN_IRQ_LAN);
+	desc->status = IRQ_DISABLED;
+	desc->chip = &m32700ut_lanpld_irq_type;
+	desc->action = 0;
+	desc->depth = 1;	/* disable nested irq */
 	lanpld_icu_data[irq2lanpldirq(M32700UT_LAN_IRQ_LAN)].icucr = PLD_ICUCR_IEN|PLD_ICUCR_ISMOD02;	/* "H" edge sense */
 	disable_m32700ut_lanpld_irq(M32700UT_LAN_IRQ_LAN);
 #endif  /* CONFIG_SMC91X */
 
 	/* MFT2 : system timer */
-	irq_desc[M32R_IRQ_MFT2].status = IRQ_DISABLED;
-	irq_desc[M32R_IRQ_MFT2].chip = &m32700ut_irq_type;
-	irq_desc[M32R_IRQ_MFT2].action = 0;
-	irq_desc[M32R_IRQ_MFT2].depth = 1;
+	desc = irq_desc(M32R_IRQ_MFT2);
+	desc->status = IRQ_DISABLED;
+	desc->chip = &m32700ut_irq_type;
+	desc->action = 0;
+	desc->depth = 1;
 	icu_data[M32R_IRQ_MFT2].icucr = M32R_ICUCR_IEN;
 	disable_m32700ut_irq(M32R_IRQ_MFT2);
 
 	/* SIO0 : receive */
-	irq_desc[M32R_IRQ_SIO0_R].status = IRQ_DISABLED;
-	irq_desc[M32R_IRQ_SIO0_R].chip = &m32700ut_irq_type;
-	irq_desc[M32R_IRQ_SIO0_R].action = 0;
-	irq_desc[M32R_IRQ_SIO0_R].depth = 1;
+	desc = irq_desc(M32R_IRQ_SIO0_R);
+	desc->status = IRQ_DISABLED;
+	desc->chip = &m32700ut_irq_type;
+	desc->action = 0;
+	desc->depth = 1;
 	icu_data[M32R_IRQ_SIO0_R].icucr = 0;
 	disable_m32700ut_irq(M32R_IRQ_SIO0_R);
 
 	/* SIO0 : send */
-	irq_desc[M32R_IRQ_SIO0_S].status = IRQ_DISABLED;
-	irq_desc[M32R_IRQ_SIO0_S].chip = &m32700ut_irq_type;
-	irq_desc[M32R_IRQ_SIO0_S].action = 0;
-	irq_desc[M32R_IRQ_SIO0_S].depth = 1;
+	desc = irq_desc(M32R_IRQ_SIO0_S);
+	desc->status = IRQ_DISABLED;
+	desc->chip = &m32700ut_irq_type;
+	desc->action = 0;
+	desc->depth = 1;
 	icu_data[M32R_IRQ_SIO0_S].icucr = 0;
 	disable_m32700ut_irq(M32R_IRQ_SIO0_S);
 
 	/* SIO1 : receive */
-	irq_desc[M32R_IRQ_SIO1_R].status = IRQ_DISABLED;
-	irq_desc[M32R_IRQ_SIO1_R].chip = &m32700ut_irq_type;
-	irq_desc[M32R_IRQ_SIO1_R].action = 0;
-	irq_desc[M32R_IRQ_SIO1_R].depth = 1;
+	desc = irq_desc(M32R_IRQ_SIO1_R);
+	desc->status = IRQ_DISABLED;
+	desc->chip = &m32700ut_irq_type;
+	desc->action = 0;
+	desc->depth = 1;
 	icu_data[M32R_IRQ_SIO1_R].icucr = 0;
 	disable_m32700ut_irq(M32R_IRQ_SIO1_R);
 
 	/* SIO1 : send */
-	irq_desc[M32R_IRQ_SIO1_S].status = IRQ_DISABLED;
-	irq_desc[M32R_IRQ_SIO1_S].chip = &m32700ut_irq_type;
-	irq_desc[M32R_IRQ_SIO1_S].action = 0;
-	irq_desc[M32R_IRQ_SIO1_S].depth = 1;
+	desc = irq_desc(M32R_IRQ_SIO1_S);
+	desc->status = IRQ_DISABLED;
+	desc->chip = &m32700ut_irq_type;
+	desc->action = 0;
+	desc->depth = 1;
 	icu_data[M32R_IRQ_SIO1_S].icucr = 0;
 	disable_m32700ut_irq(M32R_IRQ_SIO1_S);
 
 	/* DMA1 : */
-	irq_desc[M32R_IRQ_DMA1].status = IRQ_DISABLED;
-	irq_desc[M32R_IRQ_DMA1].chip = &m32700ut_irq_type;
-	irq_desc[M32R_IRQ_DMA1].action = 0;
-	irq_desc[M32R_IRQ_DMA1].depth = 1;
+	desc = irq_desc(M32R_IRQ_DMA1)
+	desc->status = IRQ_DISABLED;
+	desc->chip = &m32700ut_irq_type;
+	desc->action = 0;
+	desc->depth = 1;
 	icu_data[M32R_IRQ_DMA1].icucr = 0;
 	disable_m32700ut_irq(M32R_IRQ_DMA1);
 
 #ifdef CONFIG_SERIAL_M32R_PLDSIO
 	/* INT#1: SIO0 Receive on PLD */
-	irq_desc[PLD_IRQ_SIO0_RCV].status = IRQ_DISABLED;
-	irq_desc[PLD_IRQ_SIO0_RCV].chip = &m32700ut_pl