[IA64] Support irq migration across domain

Add support for IRQ migration across vector domain.

Signed-off-by: Kenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: Yasuaki Ishimatsu <isimatu.yasuaki@jp.fujitsu.com>
Signed-off-by: Tony Luck <tony.luck@intel.com>

1 files changed, 39 insertions, 3 deletions

diff --git a/arch/ia64/kernel/irq_ia64.c b/arch/ia64/kernel/irq_ia64.c
index a3667631ed80..22806b94025a 100644
--- a/arch/ia64/kernel/irq_ia64.c
+++ b/arch/ia64/kernel/irq_ia64.c
@@ -172,15 +172,13 @@ int bind_irq_vector(int irq, int vector, cpumask_t domain)
         return ret;
 }
 
-static void clear_irq_vector(int irq)
+static void __clear_irq_vector(int irq)
 {
-        unsigned long flags;
         int vector, cpu, pos;
         cpumask_t mask;
         cpumask_t domain;
         struct irq_cfg *cfg = &irq_cfg[irq];
 
-        spin_lock_irqsave(&vector_lock, flags);
         BUG_ON((unsigned)irq >= NR_IRQS);
         BUG_ON(cfg->vector == IRQ_VECTOR_UNASSIGNED);
         vector = cfg->vector;
@@ -193,6 +191,14 @@ static void clear_irq_vector(int irq)
         irq_status[irq] = IRQ_UNUSED;
         pos = vector - IA64_FIRST_DEVICE_VECTOR;
         cpus_andnot(vector_table[pos], vector_table[pos], domain);
+}
+
+static void clear_irq_vector(int irq)
+{
+        unsigned long flags;
+
+        spin_lock_irqsave(&vector_lock, flags);
+        __clear_irq_vector(irq);
         spin_unlock_irqrestore(&vector_lock, flags);
 }
 
@@ -275,6 +281,36 @@ void destroy_and_reserve_irq(unsigned int irq)
         reserve_irq(irq);
 }
 
+static int __reassign_irq_vector(int irq, int cpu)
+{
+        struct irq_cfg *cfg = &irq_cfg[irq];
+        int vector;
+        cpumask_t domain;
+
+        if (cfg->vector == IRQ_VECTOR_UNASSIGNED || !cpu_online(cpu))
+                return -EINVAL;
+        if (cpu_isset(cpu, cfg->domain))
+                return 0;
+        domain = vector_allocation_domain(cpu);
+        vector = find_unassigned_vector(domain);
+        if (vector < 0)
+                return -ENOSPC;
+        __clear_irq_vector(irq);
+        BUG_ON(__bind_irq_vector(irq, vector, domain));
+        return 0;
+}
+
+int reassign_irq_vector(int irq, int cpu)
+{
+        unsigned long flags;
+        int ret;
+
+        spin_lock_irqsave(&vector_lock, flags);
+        ret = __reassign_irq_vector(irq, cpu);
+        spin_unlock_irqrestore(&vector_lock, flags);
+        return ret;
+}
+
 /*
  * Dynamic irq allocate and deallocation for MSI
  */