7 files changed, 264 insertions, 473 deletions

diff --git a/arch/powerpc/platforms/cell/beat_interrupt.c b/arch/powerpc/platforms/cell/beat_interrupt.c
index 8c6dc42ecf65..9e5dfbcc00af 100644
--- a/arch/powerpc/platforms/cell/beat_interrupt.c
+++ b/arch/powerpc/platforms/cell/beat_interrupt.c
@@ -239,7 +239,7 @@ void __init beatic_init_IRQ(void)
         ppc_md.get_irq = beatic_get_irq;
 
         /* Allocate an irq host */
-        beatic_host = irq_domain_add_nomap(NULL, 0, &beatic_pic_host_ops, NULL);
+        beatic_host = irq_domain_add_nomap(NULL, ~0, &beatic_pic_host_ops, NULL);
         BUG_ON(beatic_host == NULL);
         irq_set_default_host(beatic_host);
 }
diff --git a/arch/powerpc/platforms/powermac/smp.c b/arch/powerpc/platforms/powermac/smp.c
index 49c9f9501c21..5cbd4d67d5c4 100644
--- a/arch/powerpc/platforms/powermac/smp.c
+++ b/arch/powerpc/platforms/powermac/smp.c
@@ -192,7 +192,7 @@ static int psurge_secondary_ipi_init(void)
 {
         int rc = -ENOMEM;
 
-        psurge_host = irq_domain_add_nomap(NULL, 0, &psurge_host_ops, NULL);
+        psurge_host = irq_domain_add_nomap(NULL, ~0, &psurge_host_ops, NULL);
 
         if (psurge_host)
                 psurge_secondary_virq = irq_create_direct_mapping(psurge_host);
diff --git a/arch/x86/kernel/devicetree.c b/arch/x86/kernel/devicetree.c
index b1581527a236..4934890e4db2 100644
--- a/arch/x86/kernel/devicetree.c
+++ b/arch/x86/kernel/devicetree.c
@@ -364,9 +364,7 @@ static void dt_add_ioapic_domain(unsigned int ioapic_num,
                  * and assigned so we can keep the 1:1 mapping which the ioapic
                  * is having.
                  */
-                ret = irq_domain_associate_many(id, 0, 0, NR_IRQS_LEGACY);
-                if (ret)
-                        pr_err("Error mapping legacy IRQs: %d\n", ret);
+                irq_domain_associate_many(id, 0, 0, NR_IRQS_LEGACY);
 
                 if (num > NR_IRQS_LEGACY) {
                         ret = irq_create_strict_mappings(id, NR_IRQS_LEGACY,
diff --git a/include/linux/irqdomain.h b/include/linux/irqdomain.h
index ba2c708adcff..c983ed18c332 100644
--- a/include/linux/irqdomain.h
+++ b/include/linux/irqdomain.h
@@ -73,57 +73,48 @@ struct irq_domain_chip_generic;
 /**
  * struct irq_domain - Hardware interrupt number translation object
  * @link: Element in global irq_domain list.
- * @revmap_type: Method used for reverse mapping hwirq numbers to linux irq. This
- *               will be one of the IRQ_DOMAIN_MAP_* values.
- * @revmap_data: Revmap method specific data.
+ * @name: Name of interrupt domain
  * @ops: pointer to irq_domain methods
  * @host_data: private data pointer for use by owner.  Not touched by irq_domain
  *             core code.
- * @irq_base: Start of irq_desc range assigned to the irq_domain.  The creator
- *            of the irq_domain is responsible for allocating the array of
- *            irq_desc structures.
- * @nr_irq: Number of irqs managed by the irq domain
- * @hwirq_base: Starting number for hwirqs managed by the irq domain
- * @of_node: (optional) Pointer to device tree nodes associated with the
- *           irq_domain.  Used when decoding device tree interrupt specifiers.
+ *
+ * Optional elements
+ * @of_node: Pointer to device tree nodes associated with the irq_domain. Used
+ *           when decoding device tree interrupt specifiers.
+ * @gc: Pointer to a list of generic chips. There is a helper function for
+ *      setting up one or more generic chips for interrupt controllers
+ *      drivers using the generic chip library which uses this pointer.
+ *
+ * Revmap data, used internally by irq_domain
+ * @revmap_direct_max_irq: The largest hwirq that can be set for controllers that
+ *                         support direct mapping
+ * @revmap_size: Size of the linear map table @linear_revmap[]
+ * @revmap_tree: Radix map tree for hwirqs that don't fit in the linear map
+ * @linear_revmap: Linear table of hwirq->virq reverse mappings
  */
 struct irq_domain {
         struct list_head link;
-
-        /* type of reverse mapping_technique */
-        unsigned int revmap_type;
-        union {
-                struct {
-                        unsigned int size;
-                        unsigned int first_irq;
-                        irq_hw_number_t first_hwirq;
-                } legacy;
-                struct {
-                        unsigned int size;
-                        unsigned int *revmap;
-                } linear;
-                struct {
-                        unsigned int max_irq;
-                } nomap;
-                struct radix_tree_root tree;
-        } revmap_data;
+        const char *name;
         const struct irq_domain_ops *ops;
         void *host_data;
-        irq_hw_number_t inval_irq;
 
-        /* Optional device node pointer */
+        /* Optional data */
         struct device_node *of_node;
-        /* Optional pointer to generic interrupt chips */
         struct irq_domain_chip_generic *gc;
-};
 
-#define IRQ_DOMAIN_MAP_LEGACY 0 /* driver allocated fixed range of irqs.
-                                 * ie. legacy 8259, gets irqs 1..15 */
-#define IRQ_DOMAIN_MAP_NOMAP 1 /* no fast reverse mapping */
-#define IRQ_DOMAIN_MAP_LINEAR 2 /* linear map of interrupts */
-#define IRQ_DOMAIN_MAP_TREE 3 /* radix tree */
+        /* reverse map data. The linear map gets appended to the irq_domain */
+        irq_hw_number_t hwirq_max;
+        unsigned int revmap_direct_max_irq;
+        unsigned int revmap_size;
+        struct radix_tree_root revmap_tree;
+        unsigned int linear_revmap[];
+};
 
 #ifdef CONFIG_IRQ_DOMAIN
+struct irq_domain *__irq_domain_add(struct device_node *of_node, int size,
+                                    irq_hw_number_t hwirq_max, int direct_max,
+                                    const struct irq_domain_ops *ops,
+                                    void *host_data);
 struct irq_domain *irq_domain_add_simple(struct device_node *of_node,
                                          unsigned int size,
                                          unsigned int first_irq,
@@ -135,21 +126,30 @@ struct irq_domain *irq_domain_add_legacy(struct device_node *of_node,
                                          irq_hw_number_t first_hwirq,
                                          const struct irq_domain_ops *ops,
                                          void *host_data);
-struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
+extern struct irq_domain *irq_find_host(struct device_node *node);
+extern void irq_set_default_host(struct irq_domain *host);
+
+/**
+ * irq_domain_add_linear() - Allocate and register a linear revmap irq_domain.
+ * @of_node: pointer to interrupt controller's device tree node.
+ * @size: Number of interrupts in the domain.
+ * @ops: map/unmap domain callbacks
+ * @host_data: Controller private data pointer
+ */
+static inline struct irq_domain *irq_domain_add_linear(struct device_node *of_node,
                                          unsigned int size,
                                          const struct irq_domain_ops *ops,
-                                         void *host_data);
-struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
+                                         void *host_data)
+{
+        return __irq_domain_add(of_node, size, size, 0, ops, host_data);
+}
+static inline struct irq_domain *irq_domain_add_nomap(struct device_node *of_node,
                                          unsigned int max_irq,
                                          const struct irq_domain_ops *ops,
-                                         void *host_data);
-struct irq_domain *irq_domain_add_tree(struct device_node *of_node,
-                                         const struct irq_domain_ops *ops,
-                                         void *host_data);
-
-extern struct irq_domain *irq_find_host(struct device_node *node);
-extern void irq_set_default_host(struct irq_domain *host);
-
+                                         void *host_data)
+{
+        return __irq_domain_add(of_node, 0, max_irq, max_irq, ops, host_data);
+}
 static inline struct irq_domain *irq_domain_add_legacy_isa(
                                 struct device_node *of_node,
                                 const struct irq_domain_ops *ops,
@@ -158,21 +158,40 @@ static inline struct irq_domain *irq_domain_add_legacy_isa(
         return irq_domain_add_legacy(of_node, NUM_ISA_INTERRUPTS, 0, 0, ops,