irq: remove >= nr_irqs checking with config_have_sparse_irq

remove irq limit checks - nr_irqs is dynamic and we expand anytime.

v2: fix checking about result irq_cfg_without_new, so could use msi again
v3: use irq_desc_without_new to check irq is valid

Signed-off-by: Yinghai Lu <yhlu.kernel@gmail.com>
Signed-off-by: Ingo Molnar <mingo@elte.hu>

4 files changed, 55 insertions, 48 deletions

diff --git a/arch/x86/kernel/io_apic_64.c b/arch/x86/kernel/io_apic_64.c
index 60d60061659c..1b8cccb5ba25 100644
--- a/arch/x86/kernel/io_apic_64.c
+++ b/arch/x86/kernel/io_apic_64.c
@@ -400,7 +400,6 @@ static inline void io_apic_sync(unsigned int apic)
         struct irq_cfg *cfg;                                            \
         struct irq_pin_list *entry;                                     \
                                                                         \
-        BUG_ON(irq >= nr_irqs);                                         \
         cfg = irq_cfg(irq);                                             \
         entry = cfg->irq_2_pin;                                         \
         for (;;) {                                                      \
@@ -480,7 +479,6 @@ static void __target_IO_APIC_irq(unsigned int irq, unsigned int dest, u8 vector)
         struct irq_cfg *cfg;
         struct irq_pin_list *entry;
 
-        BUG_ON(irq >= nr_irqs);
         cfg = irq_cfg(irq);
         entry = cfg->irq_2_pin;
         for (;;) {
@@ -549,7 +547,6 @@ static void add_pin_to_irq(unsigned int irq, int apic, int pin)
         struct irq_cfg *cfg;
         struct irq_pin_list *entry;
 
-        BUG_ON(irq >= nr_irqs);
         /* first time to refer irq_cfg, so with new */
         cfg = irq_cfg_alloc(irq);
         entry = cfg->irq_2_pin;
@@ -841,7 +838,6 @@ int IO_APIC_get_PCI_irq_vector(int bus, int slot, int pin)
                                 best_guess = irq;
                 }
         }
-        BUG_ON(best_guess >= nr_irqs);
         return best_guess;
 }
 
@@ -973,7 +969,6 @@ static int pin_2_irq(int idx, int apic, int pin)
                         irq += nr_ioapic_registers[i++];
                 irq += pin;
         }
-        BUG_ON(irq >= nr_irqs);
         return irq;
 }
 
@@ -1008,7 +1003,6 @@ static int __assign_irq_vector(int irq, cpumask_t mask)
         int cpu;
         struct irq_cfg *cfg;
 
-        BUG_ON((unsigned)irq >= nr_irqs);
         cfg = irq_cfg(irq);
 
         /* Only try and allocate irqs on cpus that are present */
@@ -1082,7 +1076,6 @@ static void __clear_irq_vector(int irq)
         cpumask_t mask;
         int cpu, vector;
 
-        BUG_ON((unsigned)irq >= nr_irqs);
         cfg = irq_cfg(irq);
         BUG_ON(!cfg->vector);
 
@@ -1924,8 +1917,6 @@ asmlinkage void smp_irq_move_cleanup_interrupt(void)
                 struct irq_desc *desc;
                 struct irq_cfg *cfg;
                 irq = __get_cpu_var(vector_irq)[vector];
-                if (irq >= nr_irqs)
-                        continue;
 
                 desc = irq_to_desc(irq);
                 cfg = irq_cfg(irq);
diff --git a/arch/x86/kernel/irq_64.c b/arch/x86/kernel/irq_64.c
index b3cf55e325f5..a3e36336d914 100644
--- a/arch/x86/kernel/irq_64.c
+++ b/arch/x86/kernel/irq_64.c
@@ -202,7 +202,7 @@ asmlinkage unsigned int do_IRQ(struct pt_regs *regs)
         stack_overflow_check(regs);
 #endif
 
-        if (likely(irq < nr_irqs))
+        if (likely(__irq_to_desc(irq)))
                 generic_handle_irq(irq);
         else {
                 if (!disable_apic)
diff --git a/kernel/irq/chip.c b/kernel/irq/chip.c
index 2aa3d4b2fce8..a4bb0da9c88c 100644
--- a/kernel/irq/chip.c
+++ b/kernel/irq/chip.c
@@ -27,13 +27,13 @@ void dynamic_irq_init(unsigned int irq)
         struct irq_desc *desc;
         unsigned long flags;
 
-        if (irq >= nr_irqs) {
+        desc = irq_to_desc(irq);
+        if (!desc) {
                 WARN(1, KERN_ERR "Trying to initialize invalid IRQ%d\n", irq);
                 return;
         }
 
         /* Ensure we don't have left over values from a previous use of this irq */
-        desc = irq_to_desc(irq);
         spin_lock_irqsave(&desc->lock, flags);
         desc->status = IRQ_DISABLED;
         desc->chip = &no_irq_chip;
@@ -60,12 +60,12 @@ void dynamic_irq_cleanup(unsigned int irq)
         struct irq_desc *desc;
         unsigned long flags;
 
-        if (irq >= nr_irqs) {
+        desc = __irq_to_desc(irq);
+        if (!desc) {
                 WARN(1, KERN_ERR "Trying to cleanup invalid IRQ%d\n", irq);
                 return;
         }
 
-        desc = irq_to_desc(irq);
         spin_lock_irqsave(&desc->lock, flags);
         if (desc->action) {
                 spin_unlock_irqrestore(&desc->lock, flags);
@@ -92,7 +92,8 @@ int set_irq_chip(unsigned int irq, struct irq_chip *chip)
         struct irq_desc *desc;
         unsigned long flags;
 
-        if (irq >= nr_irqs) {
+        desc = __irq_to_desc(irq);
+        if (!desc) {
                 WARN(1, KERN_ERR "Trying to install chip for IRQ%d\n", irq);
                 return -EINVAL;
         }
@@ -121,12 +122,12 @@ int set_irq_type(unsigned int irq, unsigned int type)
         unsigned long flags;
         int ret = -ENXIO;
 
-        if (irq >= nr_irqs) {
+        desc = __irq_to_desc(irq);
+        if (!desc) {
                 printk(KERN_ERR "Trying to set irq type for IRQ%d\n", irq);
                 return -ENODEV;
         }
 
-        desc = irq_to_desc(irq);
         if (type == IRQ_TYPE_NONE)
                 return 0;
 
@@ -149,13 +150,13 @@ int set_irq_data(unsigned int irq, void *data)
         struct irq_desc *desc;
         unsigned long flags;
 
-        if (irq >= nr_irqs) {
+        desc = __irq_to_desc(irq);
+        if (!desc) {
                 printk(KERN_ERR
                        "Trying to install controller data for IRQ%d\n", irq);
                 return -EINVAL;
         }
 
-        desc = irq_to_desc(irq);
         spin_lock_irqsave(&desc->lock, flags);
         desc->handler_data = data;
         spin_unlock_irqrestore(&desc->lock, flags);
@@ -175,12 +176,13 @@ int set_irq_msi(unsigned int irq, struct msi_desc *entry)
         struct irq_desc *desc;
         unsigned long flags;
 
-        if (irq >= nr_irqs) {
+        desc = __irq_to_desc(irq);
+        if (!desc) {
                 printk(KERN_ERR
                        "Trying to install msi data for IRQ%d\n", irq);
                 return -EINVAL;
         }
-        desc = irq_to_desc(irq);
+
         spin_lock_irqsave(&desc->lock, flags);
         desc->msi_desc = entry;
         if (entry)
@@ -201,8 +203,14 @@ int set_irq_chip_data(unsigned int irq, void *data)
         struct irq_desc *desc;
         unsigned long flags;
 
-        desc = irq_to_desc(irq);
-        if (irq >= nr_irqs || !desc->chip) {
+        desc = __irq_to_desc(irq);
+        if (!desc) {
+                printk(KERN_ERR
+                       "Trying to install chip data for IRQ%d\n", irq);
+                return -EINVAL;
+        }
+
+        if (!desc->chip) {
                 printk(KERN_ERR "BUG: bad set_irq_chip_data(IRQ#%d)\n", irq);
                 return -EINVAL;
         }
@@ -546,14 +554,13 @@ __set_irq_handler(unsigned int irq, irq_flow_handler_t handle, int is_chained,
         struct irq_desc *desc;
         unsigned long flags;
 
-        if (irq >= nr_irqs) {
+        desc = __irq_to_desc(irq);
+        if (!desc) {
                 printk(KERN_ERR
                        "Trying to install type control for IRQ%d\n", irq);
                 return;
         }
 
-        desc = irq_to_desc(irq);
-
         if (!handle)
                 handle = handle_bad_irq;
         else if (desc->chip == &no_irq_chip) {
@@ -611,14 +618,13 @@ void __init set_irq_noprobe(unsigned int irq)
         struct irq_desc *desc;
         unsigned long flags;
 
-        if (irq >= nr_irqs) {
+        desc = __irq_to_desc(irq);
+        if (!desc) {
                 printk(KERN_ERR "Trying to mark IRQ%d non-probeable\n", irq);
 
                 return;
         }
 
-        desc = irq_to_desc(irq);
-
         spin_lock_irqsave(&desc->lock, flags);
         desc->status |= IRQ_NOPROBE;
         spin_unlock_irqrestore(&desc->lock, flags);
@@ -629,14 +635,13 @@ void __init set_irq_probe(unsigned int irq)
         struct irq_desc *desc;
         unsigned long flags;
 
-        if (irq >= nr_irqs) {
+        desc = __irq_to_desc(irq);
+        if (!desc) {
                 printk(KERN_ERR "Trying to mark IRQ%d probeable\n", irq);
 
                 return;
         }
 
-        desc = irq_to_desc(irq);
-
         spin_lock_irqsave(&desc->lock, flags);
         desc->status &= ~IRQ_NOPROBE;
         spin_unlock_irqrestore(&desc->lock, flags);
diff --git a/kernel/irq/manage.c b/kernel/irq/manage.c
index 5070f55fdc16..c0b4d4df6de2 100644
--- a/kernel/irq/manage.c
+++ b/kernel/irq/manage.c
@@ -31,10 +31,10 @@ cpumask_t irq_default_affinity = CPU_MASK_ALL;
  */
 void synchronize_irq(unsigned int irq)
 {
-        struct irq_desc *desc = irq_to_desc(irq);
+        struct irq_desc *desc = __irq_to_desc(irq);
         unsigned int status;
 
-        if (irq >= nr_irqs)
+        if (!desc)
                 return;
 
         do {
@@ -142,10 +142,11 @@ int irq_select_affinity(unsigned int irq)
  */
 void disable_irq_nosync(unsigned int irq)
 {
-        struct irq_desc *desc = irq_to_desc(irq);
+        struct irq_desc *desc;
         unsigned long flags;
 
-        if (irq >= nr_irqs)
+        desc = __irq_to_desc(irq);
+        if (!desc)
                 return;
 
         spin_lock_irqsave(&desc->lock, flags);
@@ -171,9 +172,10 @@ EXPORT_SYMBOL(disable_irq_nosync);
  */
 void disable_irq(unsigned int irq)
 {
-        struct irq_desc *desc = irq_to_desc(irq);
+        struct irq_desc *desc;
 
-        if (irq >= nr_irqs)
+        desc = __irq_to_desc(irq);
+        if (!desc)
                 return;
 
         disable_irq_nosync(irq);
@@ -213,10 +215,11 @@ static void __enable_irq(struct irq_desc *desc, unsigned int irq)
  */
 void enable_irq(unsigned int irq)
 {
-        struct irq_desc *desc = irq_to_desc(irq);
+        struct irq_desc *desc;
         unsigned long flags;
 
-        if (irq >= nr_irqs)
+        desc = __irq_to_desc(irq);
+        if (!desc)
                 return;
 
         spin_lock_irqsave(&desc->lock, flags);
@@ -290,10 +293,14 @@ EXPORT_SYMBOL(set_irq_wake);
  */
 int can_request_irq(unsigned int irq, unsigned long irqflags)
 {
-        struct irq_desc *desc = irq_to_desc(irq);
+        struct irq_desc *desc;
         struct irqaction *action;
 
-        if (irq >= nr_irqs || desc->status & IRQ_NOREQUEST)
+        desc = __irq_to_desc(irq);
+        if (!desc)
+                return 0;
+
+        if (desc->status & IRQ_NOREQUEST)
                 return 0;
 
         action = desc->action;
@@ -352,14 +359,15 @@ int __irq_set_trigger(struct irq_desc *desc, unsigned int irq,
  */
 int setup_irq(unsigned int irq, struct irqaction *new)
 {
-        struct irq_desc *desc = irq_to_desc(irq);
+        struct irq_desc *desc;
         struct irqaction *old, **p;
         const char *old_name = NULL;
         unsigned long flags;
         int shared = 0;
         int ret;
 
-        if (irq >= nr_irqs)
+        desc = __irq_to_desc(irq);
+        if (!desc)
                 return -EINVAL;
 
         if (desc->chip == &no_irq_chip)
@@ -518,10 +526,11 @@ void free_irq(unsigned int irq, void *dev_id)
         unsigned long flags;
 
         WARN_ON(in_interrupt());
-        if (irq >= nr_irqs)
+
+        desc = __irq_to_desc(irq);
+        if (!desc)
                 return;
 
-        desc = irq_to_desc(irq);
         spin_lock_irqsave(&desc->lock, flags);
         p = &desc->action;
         for (;;) {
@@ -634,9 +643,11 @@ int request_irq(unsigned int irq, irq_handler_t handler,
          */
         if ((irqflags & IRQF_SHARED) && !dev_id)
                 return -EINVAL;
-        if (irq >= nr_irqs)
+
+        desc = __irq_to_desc(irq);
+        if (!desc)
                 return -EINVAL;
-        desc = irq_to_desc(irq);
+
         if (desc->status & IRQ_NOREQUEST)
                 return -EINVAL;
         if (!handler)