vserver 1.9.5.x5

[linux-2.6.git] / arch / ia64 / kernel / iosapic.c

diff --git a/arch/ia64/kernel/iosapic.c b/arch/ia64/kernel/iosapic.c
index 51548a8..111dad9 100644 (file)
--- a/arch/ia64/kernel/iosapic.c
+++ b/arch/ia64/kernel/iosapic.c
@@ -99,7 +99,7 @@
 #define DBG(fmt...)
 #endif
 
-static spinlock_t iosapic_lock = SPIN_LOCK_UNLOCKED;
+static DEFINE_SPINLOCK(iosapic_lock);
 
 /* These tables map IA-64 vectors to the IOSAPIC pin that generates this vector. */
 
@@ -111,6 +111,7 @@ static struct iosapic_intr_info {
        unsigned char   dmode   : 3;    /* delivery mode (see iosapic.h) */
        unsigned char   polarity: 1;    /* interrupt polarity (see iosapic.h) */
        unsigned char   trigger : 1;    /* trigger mode (see iosapic.h) */
+       int             refcnt;         /* reference counter */
 } iosapic_intr_info[IA64_NUM_VECTORS];
 
 static struct iosapic {
@@ -177,7 +178,7 @@ gsi_to_irq (unsigned int gsi)
 static void
 set_rte (unsigned int vector, unsigned int dest, int mask)
 {
-       unsigned long pol, trigger, dmode, flags;
+       unsigned long pol, trigger, dmode;
        u32 low32, high32;
        char __iomem *addr;
        int rte_index;
@@ -218,13 +219,9 @@ set_rte (unsigned int vector, unsigned int dest, int mask)
        /* dest contains both id and eid */
        high32 = (dest << IOSAPIC_DEST_SHIFT);
 
-       spin_lock_irqsave(&iosapic_lock, flags);
-       {
-               iosapic_write(addr, IOSAPIC_RTE_HIGH(rte_index), high32);
-               iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
-               iosapic_intr_info[vector].low32 = low32;
-       }
-       spin_unlock_irqrestore(&iosapic_lock, flags);
+       iosapic_write(addr, IOSAPIC_RTE_HIGH(rte_index), high32);
+       iosapic_write(addr, IOSAPIC_RTE_LOW(rte_index), low32);
+       iosapic_intr_info[vector].low32 = low32;
 }
 
 static void
@@ -475,6 +472,7 @@ register_intr (unsigned int gsi, int vector, unsigned char delivery,
        iosapic_intr_info[vector].addr     = iosapic_address;
        iosapic_intr_info[vector].gsi_base = gsi_base;
        iosapic_intr_info[vector].trigger  = trigger;
+       iosapic_intr_info[vector].refcnt++;
 
        if (trigger == IOSAPIC_EDGE)
                irq_type = &irq_type_iosapic_edge;
@@ -521,7 +519,12 @@ get_target_cpu (unsigned int gsi, int vector)
                        goto skip_numa_setup;
 
                cpu_mask = node_to_cpumask(iosapic_lists[iosapic_index].node);
-               
+
+               for_each_cpu_mask(numa_cpu, cpu_mask) {
+                       if (!cpu_online(numa_cpu))
+                               cpu_clear(numa_cpu, cpu_mask);
+               }
+
                num_cpus = cpus_weight(cpu_mask);
 
                if (!num_cpus)
@@ -576,6 +579,7 @@ iosapic_register_intr (unsigned int gsi,
        {
                vector = gsi_to_vector(gsi);
                if (vector > 0) {
+                       iosapic_intr_info[vector].refcnt++;
                        spin_unlock_irqrestore(&iosapic_lock, flags);
                        return vector;
                }
@@ -584,6 +588,8 @@ iosapic_register_intr (unsigned int gsi,
                dest = get_target_cpu(gsi, vector);
                register_intr(gsi, vector, IOSAPIC_LOWEST_PRIORITY,
                        polarity, trigger);
+
+               set_rte(vector, dest, 1);
        }
        spin_unlock_irqrestore(&iosapic_lock, flags);
 
@@ -592,10 +598,87 @@ iosapic_register_intr (unsigned int gsi,
               (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
               cpu_logical_id(dest), dest, vector);
 
-       set_rte(vector, dest, 1);
        return vector;
 }
 
+#ifdef CONFIG_ACPI_DEALLOCATE_IRQ
+void
+iosapic_unregister_intr (unsigned int gsi)
+{
+       unsigned long flags;
+       int irq, vector;
+       irq_desc_t *idesc;
+       int rte_index;
+       unsigned long trigger, polarity;
+
+       /*
+        * If the irq associated with the gsi is not found,
+        * iosapic_unregister_intr() is unbalanced. We need to check
+        * this again after getting locks.
+        */
+       irq = gsi_to_irq(gsi);
+       if (irq < 0) {
+               printk(KERN_ERR "iosapic_unregister_intr(%u) unbalanced\n", gsi);
+               WARN_ON(1);
+               return;
+       }
+       vector = irq_to_vector(irq);
+
+       idesc = irq_descp(irq);
+       spin_lock_irqsave(&idesc->lock, flags);
+       spin_lock(&iosapic_lock);
+       {
+               rte_index = iosapic_intr_info[vector].rte_index;
+               if (rte_index < 0) {
+                       spin_unlock(&iosapic_lock);
+                       spin_unlock_irqrestore(&idesc->lock, flags);
+                       printk(KERN_ERR "iosapic_unregister_intr(%u) unbalanced\n", gsi);
+                       WARN_ON(1);
+                       return;
+               }
+
+               if (--iosapic_intr_info[vector].refcnt > 0) {
+                       spin_unlock(&iosapic_lock);
+                       spin_unlock_irqrestore(&idesc->lock, flags);
+                       return;
+               }
+
+               /*
+                * If interrupt handlers still exist on the irq
+                * associated with the gsi, don't unregister the
+                * interrupt.
+                */
+               if (idesc->action) {
+                       iosapic_intr_info[vector].refcnt++;
+                       spin_unlock(&iosapic_lock);
+                       spin_unlock_irqrestore(&idesc->lock, flags);
+                       printk(KERN_WARNING "Cannot unregister GSI. IRQ %u is still in use.\n", irq);
+                       return;
+               }
+
+               /* Clear the interrupt controller descriptor. */
+               idesc->handler = &no_irq_type;
+
+               trigger  = iosapic_intr_info[vector].trigger;
+               polarity = iosapic_intr_info[vector].polarity;
+
+               /* Clear the interrupt information. */
+               memset(&iosapic_intr_info[vector], 0, sizeof(struct iosapic_intr_info));
+               iosapic_intr_info[vector].rte_index = -1;       /* mark as unused */
+       }
+       spin_unlock(&iosapic_lock);
+       spin_unlock_irqrestore(&idesc->lock, flags);
+
+       /* Free the interrupt vector */
+       free_irq_vector(vector);
+
+       printk(KERN_INFO "GSI %u (%s, %s) -> vector %d unregisterd.\n",
+              gsi, (trigger == IOSAPIC_EDGE ? "edge" : "level"),
+              (polarity == IOSAPIC_POL_HIGH ? "high" : "low"),
+              vector);
+}
+#endif /* CONFIG_ACPI_DEALLOCATE_IRQ */
+
 /*
  * ACPI calls this when it finds an entry for a platform interrupt.
  * Note that the irq_base and IOSAPIC address must be set in iosapic_init().