[RFC PATCH 4/6] powerpc/pseries: Generalize hcall_vphn()

["Naveen N. Rao" <naveen.n.rao@linux.vnet.ibm.com>]

H_HOME_NODE_ASSOCIATIVITY hcall can take two different flags and return
different associativity information in each case. Generalize the
existing hcall_vphn() function to take flags as an argument and to
return the result. Update the only existing user to pass the proper
arguments.

Signed-off-by: Naveen N. Rao <naveen.n.rao@linux.vnet.ibm.com>
---
 arch/powerpc/mm/book3s64/vphn.h |  8 ++++++++
 arch/powerpc/mm/numa.c          | 27 +++++++++++++--------------
 2 files changed, 21 insertions(+), 14 deletions(-)

diff --git a/arch/powerpc/mm/book3s64/vphn.h b/arch/powerpc/mm/book3s64/vphn.h
index f0b93c2dd578..f7ff1e0c3801 100644
--- a/arch/powerpc/mm/book3s64/vphn.h
+++ b/arch/powerpc/mm/book3s64/vphn.h
@@ -11,6 +11,14 @@
  */
 #define VPHN_ASSOC_BUFSIZE (VPHN_REGISTER_COUNT*sizeof(u64)/sizeof(u16) + 1)
 
+/*
+ * The H_HOME_NODE_ASSOCIATIVITY hcall takes two values for flags:
+ * 1 for retrieving associativity information for a guest cpu
+ * 2 for retrieving associativity information for a host/hypervisor cpu
+ */
+#define VPHN_FLAG_VCPU	1
+#define VPHN_FLAG_PCPU	2
+
 extern int vphn_unpack_associativity(const long *packed, __be32 *unpacked);
 
 #endif
diff --git a/arch/powerpc/mm/numa.c b/arch/powerpc/mm/numa.c
index 57e64273cb33..57f006b6214b 100644
--- a/arch/powerpc/mm/numa.c
+++ b/arch/powerpc/mm/numa.c
@@ -1087,6 +1087,17 @@ static void reset_topology_timer(void);
 static int topology_timer_secs = 1;
 static int topology_inited;
 
+static long hcall_vphn(unsigned long cpu, u64 flags, __be32 *associativity)
+{
+	long rc;
+	long retbuf[PLPAR_HCALL9_BUFSIZE] = {0};
+
+	rc = plpar_hcall9(H_HOME_NODE_ASSOCIATIVITY, retbuf, flags, cpu);
+	vphn_unpack_associativity(retbuf, associativity);
+
+	return rc;
+}
+
 /*
  * Change polling interval for associativity changes.
  */
@@ -1165,25 +1176,13 @@ static int update_cpu_associativity_changes_mask(void)
  * Retrieve the new associativity information for a virtual processor's
  * home node.
  */
-static long hcall_vphn(unsigned long cpu, __be32 *associativity)
-{
-	long rc;
-	long retbuf[PLPAR_HCALL9_BUFSIZE] = {0};
-	u64 flags = 1;
-	int hwcpu = get_hard_smp_processor_id(cpu);
-
-	rc = plpar_hcall9(H_HOME_NODE_ASSOCIATIVITY, retbuf, flags, hwcpu);
-	vphn_unpack_associativity(retbuf, associativity);
-
-	return rc;
-}
-
 static long vphn_get_associativity(unsigned long cpu,
 					__be32 *associativity)
 {
 	long rc;
 
-	rc = hcall_vphn(cpu, associativity);
+	rc = hcall_vphn(get_hard_smp_processor_id(cpu),
+				VPHN_FLAG_VCPU, associativity);
 
 	switch (rc) {
 	case H_FUNCTION:
-- 
2.21.0