[PATCH v3 09/18] powerpc/vas: Create cpu to vas id mapping

[Sukadev Bhattiprolu]

Create a cpu to vasid mapping so callers can specify -1 instead of
trying to find a VAS id.

Changelog[v2]
        [Michael Ellerman] Use per-cpu variables to simplify code.

Signed-off-by: Sukadev Bhattiprolu <suka...@linux.vnet.ibm.com>
---
 arch/powerpc/platforms/powernv/vas.c | 14 +++++++++++++-
 1 file changed, 13 insertions(+), 1 deletion(-)

diff --git a/arch/powerpc/platforms/powernv/vas.c 
b/arch/powerpc/platforms/powernv/vas.c
index 565a487..abb7090 100644
--- a/arch/powerpc/platforms/powernv/vas.c
+++ b/arch/powerpc/platforms/powernv/vas.c
@@ -18,15 +18,18 @@
 #include <linux/of_platform.h>
 #include <linux/of_address.h>
 #include <linux/of.h>
+#include <asm/prom.h>
 
 #include "vas.h"
 
 static DEFINE_MUTEX(vas_mutex);
 static LIST_HEAD(vas_instances);
 
+static DEFINE_PER_CPU(int, cpu_vas_id);
+
 static int init_vas_instance(struct platform_device *pdev)
 {
-       int rc, vasid;
+       int rc, cpu, vasid;
        struct resource *res;
        struct vas_instance *vinst;
        struct device_node *dn = pdev->dev.of_node;
@@ -74,6 +77,11 @@ static int init_vas_instance(struct platform_device *pdev)
                        "paste_win_id_shift 0x%llx\n", pdev->name, vasid,
                        vinst->paste_base_addr, vinst->paste_win_id_shift);
 
+       for_each_possible_cpu(cpu) {
+               if (cpu_to_chip_id(cpu) == of_get_ibm_chip_id(dn))
+                       per_cpu(cpu_vas_id, cpu) = vasid;
+       }
+
        mutex_lock(&vas_mutex);
        list_add(&vinst->node, &vas_instances);
        mutex_unlock(&vas_mutex);
@@ -98,6 +106,10 @@ struct vas_instance *find_vas_instance(int vasid)
        struct vas_instance *vinst;
 
        mutex_lock(&vas_mutex);
+
+       if (vasid == -1)
+               vasid = per_cpu(cpu_vas_id, smp_processor_id());
+
        list_for_each(ent, &vas_instances) {
                vinst = list_entry(ent, struct vas_instance, node);
                if (vinst->vas_id == vasid) {
-- 
2.7.4