4 files changed, 79 insertions, 30 deletions

diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 3e0eaaa1a339..b157e94637bf 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -34,7 +34,7 @@ config X86
         select HAVE_GENERIC_DMA_COHERENT if X86_32
         select HAVE_EFFICIENT_UNALIGNED_ACCESS
         select HAVE_DYN_ARRAY
-        select HAVE_SPARSE_IRQ if X86_64
+        select HAVE_SPARSE_IRQ
 
 config ARCH_DEFCONFIG
         string
diff --git a/arch/x86/kernel/io_apic_32.c b/arch/x86/kernel/io_apic_32.c
index 59d2e8a273e3..66c0a91362a7 100644
--- a/arch/x86/kernel/io_apic_32.c
+++ b/arch/x86/kernel/io_apic_32.c
@@ -595,7 +595,6 @@ static void set_ioapic_affinity_irq(unsigned int irq, cpumask_t cpumask)
         struct irq_pin_list *entry;
         unsigned int apicid_value;
         cpumask_t tmp;
-        struct irq_desc *desc;
 
 
         cfg = irq_cfg(irq);
@@ -620,8 +619,7 @@ static void set_ioapic_affinity_irq(unsigned int irq, cpumask_t cpumask)
                         break;
                 entry = entry->next;
         }
-        desc = irq_to_desc(irq);
-        desc->affinity = cpumask;
+        irq_to_desc(irq)->affinity = cpumask;
         spin_unlock_irqrestore(&ioapic_lock, flags);
 }
 
@@ -1055,8 +1053,6 @@ static int __assign_irq_vector(int irq)
         int vector, offset;
         struct irq_cfg *cfg;
 
-        BUG_ON((unsigned)irq >= nr_irqs);
-
         cfg = irq_cfg(irq);
         if (cfg->vector > 0)
                 return cfg->vector;
@@ -1103,7 +1099,12 @@ static void ioapic_register_intr(int irq, int vector, unsigned long trigger)
 {
         struct irq_desc *desc;
 
-        desc = irq_to_desc(irq);
+        /* first time to use this irq_desc */
+        if (irq < 16)
+                desc = irq_to_desc(irq);
+        else
+                desc = irq_to_desc_alloc(irq);
+
         if ((trigger == IOAPIC_AUTO && IO_APIC_irq_trigger(irq)) ||
             trigger == IOAPIC_LEVEL) {
                 desc->status |= IRQ_LEVEL;
@@ -2330,16 +2331,19 @@ device_initcall(ioapic_init_sysfs);
 /*
  * Dynamic irq allocate and deallocation
  */
-int create_irq(void)
+unsigned int create_irq_nr(unsigned int irq_want)
 {
         /* Allocate an unused irq */
-        int irq, new, vector = 0;
+        unsigned int irq, new, vector = 0;
         unsigned long flags;
         struct irq_cfg *cfg_new;
 
-        irq = -ENOSPC;
+        /* only can use bus/dev/fn.. when per_cpu vector is used */
+        irq_want = nr_irqs - 1;
+
+        irq = 0;
         spin_lock_irqsave(&vector_lock, flags);
-        for (new = (nr_irqs - 1); new >= 0; new--) {
+        for (new = (nr_irqs - 1); new > 0; new--) {
                 if (platform_legacy_irq(new))
                         continue;
                 cfg_new = irq_cfg(new);
@@ -2354,13 +2358,18 @@ int create_irq(void)
         }
         spin_unlock_irqrestore(&vector_lock, flags);
 
-        if (irq >= 0) {
+        if (irq > 0) {
                 set_intr_gate(vector, interrupt[irq]);
                 dynamic_irq_init(irq);
         }
         return irq;
 }
 
+int create_irq(void)
+{
+        return create_irq_nr(nr_irqs - 1);
+}
+
 void destroy_irq(unsigned int irq)
 {
         unsigned long flags;
@@ -2415,7 +2424,6 @@ static void set_msi_irq_affinity(unsigned int irq, cpumask_t mask)
         unsigned int dest;
         cpumask_t tmp;
         int vector;
-        struct irq_desc *desc;
 
         cpus_and(tmp, mask, cpu_online_map);
         if (cpus_empty(tmp))
@@ -2435,8 +2443,7 @@ static void set_msi_irq_affinity(unsigned int irq, cpumask_t mask)
         msg.address_lo |= MSI_ADDR_DEST_ID(dest);
 
         write_msi_msg(irq, &msg);
-        desc = irq_to_desc(irq);
-        desc->affinity = mask;
+        irq_to_desc(irq)->affinity = mask;
 }
 #endif /* CONFIG_SMP */
 
@@ -2455,13 +2462,31 @@ static struct irq_chip msi_chip = {
         .retrigger      = ioapic_retrigger_irq,
 };
 
+static unsigned int build_irq_for_pci_dev(struct pci_dev *dev)
+{
+        unsigned int irq;
+
+        irq = dev->bus->number;
+        irq <<= 8;
+        irq |= dev->devfn;
+        irq <<= 12;
+
+        return irq;
+}
+
 int arch_setup_msi_irq(struct pci_dev *dev, struct msi_desc *desc)
 {
         struct msi_msg msg;
         int irq, ret;
-        irq = create_irq();
-        if (irq < 0)
-                return irq;
+
+        unsigned int irq_want;
+
+        irq_want = build_irq_for_pci_dev(dev) + 0x100;
+
+        irq = create_irq_nr(irq_want);
+
+        if (irq == 0)
+                return -1;
 
         ret = msi_compose_msg(dev, irq, &msg);
         if (ret < 0) {
@@ -2510,7 +2535,6 @@ static void set_ht_irq_affinity(unsigned int irq, cpumask_t mask)
 {
         unsigned int dest;
         cpumask_t tmp;
-        struct irq_desc *desc;
 
         cpus_and(tmp, mask, cpu_online_map);
         if (cpus_empty(tmp))
@@ -2521,8 +2545,7 @@ static void set_ht_irq_affinity(unsigned int irq, cpumask_t mask)
         dest = cpu_mask_to_apicid(mask);
 
         target_ht_irq(irq, dest);
-        desc = irq_to_desc(irq);
-        desc->affinity = mask;
+        irq_to_desc(irq)->affinity = mask;
 }
 #endif
 
diff --git a/arch/x86/kernel/irq_32.c b/arch/x86/kernel/irq_32.c
index 576c5df6cad8..0a57e39159a8 100644
--- a/arch/x86/kernel/irq_32.c
+++ b/arch/x86/kernel/irq_32.c
@@ -224,9 +224,10 @@ unsigned int do_IRQ(struct pt_regs *regs)
         struct pt_regs *old_regs;
         /* high bit used in ret_from_ code */
         int overflow, irq = ~regs->orig_ax;
-        struct irq_desc *desc = irq_to_desc(irq);
+        struct irq_desc *desc;
 
-        if (unlikely((unsigned)irq >= nr_irqs)) {
+        desc = irq_to_desc(irq);
+        if (unlikely(!desc)) {
                 printk(KERN_EMERG "%s: cannot handle IRQ %d\n",
                                         __func__, irq);
                 BUG();
@@ -263,6 +264,24 @@ int show_interrupts(struct seq_file *p, void *v)
         int i = *(loff_t *) v, j;
         struct irqaction * action;
         unsigned long flags;
+        unsigned int entries;
+        struct irq_desc *desc;
+        int tail = 0;
+
+#ifdef CONFIG_HAVE_SPARSE_IRQ
+        desc = (struct irq_desc *)v;
+        entries = -1U;
+        i = desc->irq;
+        if (!desc->next)
+                tail = 1;
+#else
+        entries = nr_irqs - 1;
+        i = *(loff_t *) v;
+        if (i == nr_irqs)
+                tail = 1;
+        else
+                desc = irq_to_desc(i);
+#endif
 
         if (i == 0) {
                 seq_printf(p, "           ");
@@ -271,9 +290,8 @@ int show_interrupts(struct seq_file *p, void *v)
                 seq_putc(p, '\n');
         }
 
-        if (i < nr_irqs) {
+        if (i <= entries) {
                 unsigned any_count = 0;
-                struct irq_desc *desc = irq_to_desc(i);
 
                 spin_lock_irqsave(&desc->lock, flags);
 #ifndef CONFIG_SMP
@@ -285,7 +303,7 @@ int show_interrupts(struct seq_file *p, void *v)
                 action = desc->action;
                 if (!action && !any_count)
                         goto skip;
-                seq_printf(p, "%3d: ",i);
+                seq_printf(p, "%#x: ",i);
 #ifndef CONFIG_SMP
                 seq_printf(p, "%10u ", kstat_irqs(i));
 #else
@@ -304,7 +322,9 @@ int show_interrupts(struct seq_file *p, void *v)
                 seq_putc(p, '\n');
 skip:
                 spin_unlock_irqrestore(&desc->lock, flags);
-        } else if (i == nr_irqs) {
+        }
+
+        if (tail) {
                 seq_printf(p, "NMI: ");
                 for_each_online_cpu(j)
                         seq_printf(p, "%10u ", nmi_count(j));
@@ -396,15 +416,14 @@ void fixup_irqs(cpumask_t map)
 {
         unsigned int irq;
         static int warned;
+        struct irq_desc *desc;
 
-        for (irq = 0; irq < nr_irqs; irq++) {
+        for_each_irq_desc(irq, desc) {
                 cpumask_t mask;
-                struct irq_desc *desc;
 
                 if (irq == 2)
                         continue;
 
-                desc = irq_to_desc(irq);
                 cpus_and(mask, desc->affinity, map);
                 if (any_online_cpu(mask) == NR_CPUS) {
                         printk("Breaking affinity for irq %i\n", irq);
diff --git a/arch/x86/kernel/irqinit_32.c b/arch/x86/kernel/irqinit_32.c
index 65c1c9507707..ded09ac2642e 100644
--- a/arch/x86/kernel/irqinit_32.c
+++ b/arch/x86/kernel/irqinit_32.c
@@ -69,6 +69,13 @@ void __init init_ISA_irqs (void)
          * 16 old-style INTA-cycle interrupts:
          */
         for (i = 0; i < 16; i++) {
+                /* first time call this irq_desc */
+                struct irq_desc *desc = irq_to_desc_alloc(i);
+
+                desc->status = IRQ_DISABLED;
+                desc->action = NULL;
+                desc->depth = 1;
+
                 set_irq_chip_and_handler_name(i, &i8259A_chip,
                                               handle_level_irq, "XT");
         }