Re: [PATCH V2 19/31] powerpc/mm: Convert 4k hash insert to C

Signed-off-by: Aneesh Kumar K.V <redacted>
---
 arch/powerpc/mm/Makefile        |   3 +
 arch/powerpc/mm/hash64_64k.c    | 202 +++++++++++++++++++++
 arch/powerpc/mm/hash_low_64.S   | 380 ----------------------------------------
 arch/powerpc/mm/hash_utils_64.c |   4 +-
 4 files changed, 208 insertions(+), 381 deletions(-)
 create mode 100644 arch/powerpc/mm/hash64_64k.c

diff --git a/arch/powerpc/mm/Makefile b/arch/powerpc/mm/Makefile
index 3eb73a38220d..f80ad1a76cc8 100644
--- a/arch/powerpc/mm/Makefile
+++ b/arch/powerpc/mm/Makefile

@@ -18,6 +18,9 @@ obj-$(CONFIG_PPC_STD_MMU_32)	+= ppc_mmu_32.o
 obj-$(CONFIG_PPC_STD_MMU)	+= hash_low_$(CONFIG_WORD_SIZE).o \
 				   tlb_hash$(CONFIG_WORD_SIZE).o \
 				   mmu_context_hash$(CONFIG_WORD_SIZE).o
+ifeq ($(CONFIG_PPC_STD_MMU_64),y)
+obj-$(CONFIG_PPC_64K_PAGES)	+= hash64_64k.o
+endif
 obj-$(CONFIG_PPC_ICSWX)		+= icswx.o
 obj-$(CONFIG_PPC_ICSWX_PID)	+= icswx_pid.o
 obj-$(CONFIG_40x)		+= 40x_mmu.o

diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c
new file mode 100644
index 000000000000..b137e50a3e57
--- /dev/null
+++ b/arch/powerpc/mm/hash64_64k.c

@@ -0,0 +1,202 @@
+/*
+ * Copyright IBM Corporation, 2015
+ * Author Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of version 2.1 of the GNU Lesser General Public License
+ * as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope that it would be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.
+ *
+ */
+
+#include <linux/mm.h>
+#include <asm/machdep.h>
+#include <asm/mmu.h>
+
+int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
+		   pte_t *ptep, unsigned long trap, unsigned long flags,
+		   int ssize, int subpg_prot)
+{
+	real_pte_t rpte;
+	unsigned long *hidxp;
+	unsigned long hpte_group;
+	unsigned int subpg_index;
+	unsigned long shift = 12; /* 4K */
+	unsigned long rflags, pa, hidx;
+	unsigned long old_pte, new_pte, subpg_pte;
+	unsigned long vpn, hash, slot;
+
+	/*
+	 * atomically mark the linux large page PTE busy and dirty
+	 */
+	do {
+		pte_t pte = READ_ONCE(*ptep);
+
+		old_pte = pte_val(pte);
+		/* If PTE busy, retry the access */