From f437d1f16ad77edfb114dcc68c7ee4a505cdc924 Mon Sep 17 00:00:00 2001
From: Ram Pai <linuxram@us.ibm.com>
Date: Mon, 6 Nov 2017 00:50:46 -0800
Subject: [PATCH 13/45] powerpc: introduce pte_get_hash_gslot() helper
References: FATE#322447, bsc#1078248
Patch-mainline: v4.16-rc1
Git-commit: 318995b4f5fa814b9f9aa434ca845b9a2cb0ae02
Introduce pte_get_hash_gslot()() which returns the global slot number of
the HPTE in the global hash table.
This function will come in handy as we work towards re-arranging the PTE
bits in the later patches.
Reviewed-by: Aneesh Kumar K.V <aneesh.kumar@linux.vnet.ibm.com>
Signed-off-by: Ram Pai <linuxram@us.ibm.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Acked-by: Michal Suchanek <msuchanek@suse.de>
---
arch/powerpc/include/asm/book3s/64/hash.h | 3 +++
arch/powerpc/mm/hash_utils_64.c | 18 ++++++++++++++++++
2 files changed, 21 insertions(+)
diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h
index c9d89b6d0eba..da3199c3c90d 100644
--- a/arch/powerpc/include/asm/book3s/64/hash.h
+++ b/arch/powerpc/include/asm/book3s/64/hash.h
@@ -165,6 +165,9 @@ static inline int hash__pte_none(pte_t pte)
return (pte_val(pte) & ~H_PTE_NONE_MASK) == 0;
}
+unsigned long pte_get_hash_gslot(unsigned long vpn, unsigned long shift,
+ int ssize, real_pte_t rpte, unsigned int subpg_index);
+
/* This low level function performs the actual PTE insertion
* Setting the PTE depends on the MMU type and other factors. It's
* an horrible mess that I'm not going to try to clean up now but
diff --git a/arch/powerpc/mm/hash_utils_64.c b/arch/powerpc/mm/hash_utils_64.c
index a93137c358ea..3e33cff32fa8 100644
--- a/arch/powerpc/mm/hash_utils_64.c
+++ b/arch/powerpc/mm/hash_utils_64.c
@@ -1592,6 +1592,24 @@ static inline void tm_flush_hash_page(int local)
}
#endif
+/*
+ * Return the global hash slot, corresponding to the given PTE, which contains
+ * the HPTE.
+ */
+unsigned long pte_get_hash_gslot(unsigned long vpn, unsigned long shift,
+ int ssize, real_pte_t rpte, unsigned int subpg_index)
+{
+ unsigned long hash, gslot, hidx;
+
+ hash = hpt_hash(vpn, shift, ssize);
+ hidx = __rpte_to_hidx(rpte, subpg_index);
+ if (hidx & _PTEIDX_SECONDARY)
+ hash = ~hash;
+ gslot = (hash & htab_hash_mask) * HPTES_PER_GROUP;
+ gslot += hidx & _PTEIDX_GROUP_IX;
+ return gslot;
+}
+
/* WARNING: This is called from hash_low_64.S, if you change this prototype,
* do not forget to update the assembly call site !
*/
--
2.13.6