cpumask: powerpc: Introduce cpumask_of_{node,pcibus} to replace {node,pcibus}_to_cpumask

Impact: New APIs

The old node_to_cpumask/node_to_pcibus returned a cpumask_t: these
return a pointer to a struct cpumask.  Part of removing cpumasks from
the stack.

(Also replaces powerpc internal uses of node_to_cpumask).

Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
diff --git a/arch/powerpc/include/asm/topology.h b/arch/powerpc/include/asm/topology.h
index c32da6f..bcf25c2 100644
--- a/arch/powerpc/include/asm/topology.h
+++ b/arch/powerpc/include/asm/topology.h
@@ -22,11 +22,11 @@
 	return numa_cpumask_lookup_table[node];
 }
 
+#define cpumask_of_node(node) (&numa_cpumask_lookup_table[node])
+
 static inline int node_to_first_cpu(int node)
 {
-	cpumask_t tmp;
-	tmp = node_to_cpumask(node);
-	return first_cpu(tmp);
+	return cpumask_first(cpumask_of_node(node));
 }
 
 int of_node_to_nid(struct device_node *device);
@@ -46,6 +46,10 @@
 					node_to_cpumask(pcibus_to_node(bus)) \
 				)
 
+#define cpumask_of_pcibus(bus)	(pcibus_to_node(bus) == -1 ?		\
+				 cpu_all_mask :				\
+				 cpumask_of_node(pcibus_to_node(bus)))
+
 /* sched_domains SD_NODE_INIT for PPC64 machines */
 #define SD_NODE_INIT (struct sched_domain) {		\
 	.span			= CPU_MASK_NONE,	\