[PATCH v3 22/31] powerpc/mm: Don't track subpage valid bit in pte_t
Aneesh Kumar K.V
aneesh.kumar at linux.vnet.ibm.com
Tue Oct 13 05:40:06 AEDT 2015
This free up 11 bits in pte_t. In the later patch we also change
the pte_t format so that we can start supporting migration pte
at pmd level.
Signed-off-by: Aneesh Kumar K.V <aneesh.kumar at linux.vnet.ibm.com>
---
arch/powerpc/include/asm/book3s/64/hash-4k.h | 10 +--------
arch/powerpc/include/asm/book3s/64/hash-64k.h | 29 ++-------------------------
arch/powerpc/include/asm/book3s/64/hash.h | 4 ++++
arch/powerpc/mm/hash64_64k.c | 4 ++--
arch/powerpc/mm/hash_low_64.S | 6 +-----
arch/powerpc/mm/hugetlbpage-hash64.c | 5 +----
arch/powerpc/mm/pgtable_64.c | 2 +-
7 files changed, 12 insertions(+), 48 deletions(-)
diff --git a/arch/powerpc/include/asm/book3s/64/hash-4k.h b/arch/powerpc/include/asm/book3s/64/hash-4k.h
index 537eacecf6e9..75e8b9326e4b 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-4k.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-4k.h
@@ -47,17 +47,9 @@
/* Bits to mask out from a PGD to get to the PUD page */
#define PGD_MASKED_BITS 0
-/* PTE bits */
-#define _PAGE_HASHPTE 0x0400 /* software: pte has an associated HPTE */
-#define _PAGE_SECONDARY 0x8000 /* software: HPTE is in secondary group */
-#define _PAGE_GROUP_IX 0x7000 /* software: HPTE index within group */
-#define _PAGE_F_SECOND _PAGE_SECONDARY
-#define _PAGE_F_GIX _PAGE_GROUP_IX
-#define _PAGE_SPECIAL 0x10000 /* software: special page */
-
/* PTE flags to conserve for HPTE identification */
#define _PAGE_HPTEFLAGS (_PAGE_BUSY | _PAGE_HASHPTE | \
- _PAGE_SECONDARY | _PAGE_GROUP_IX)
+ _PAGE_F_SECOND | _PAGE_F_GIX)
/* shift to put page number into pte */
#define PTE_RPN_SHIFT (17)
diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h
index dafc2f31c843..b363d73ca225 100644
--- a/arch/powerpc/include/asm/book3s/64/hash-64k.h
+++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h
@@ -31,33 +31,8 @@
/* Bits to mask out from a PGD/PUD to get to the PMD page */
#define PUD_MASKED_BITS 0x1ff
-/* Additional PTE bits (don't change without checking asm in hash_low.S) */
-#define _PAGE_SPECIAL 0x00000400 /* software: special page */
-#define _PAGE_HPTE_SUB 0x0ffff000 /* combo only: sub pages HPTE bits */
-#define _PAGE_HPTE_SUB0 0x08000000 /* combo only: first sub page */
-#define _PAGE_COMBO 0x10000000 /* this is a combo 4k page */
-#define _PAGE_4K_PFN 0x20000000 /* PFN is for a single 4k page */
-
-/* For 64K page, we don't have a separate _PAGE_HASHPTE bit. Instead,
- * we set that to be the whole sub-bits mask. The C code will only
- * test this, so a multi-bit mask will work. For combo pages, this
- * is equivalent as effectively, the old _PAGE_HASHPTE was an OR of
- * all the sub bits. For real 64k pages, we now have the assembly set
- * _PAGE_HPTE_SUB0 in addition to setting the HIDX bits which overlap
- * that mask. This is fine as long as the HIDX bits are never set on
- * a PTE that isn't hashed, which is the case today.
- *
- * A little nit is for the huge page C code, which does the hashing
- * in C, we need to provide which bit to use.
- */
-#define _PAGE_HASHPTE _PAGE_HPTE_SUB
-
-/* Note the full page bits must be in the same location as for normal
- * 4k pages as the same assembly will be used to insert 64K pages
- * whether the kernel has CONFIG_PPC_64K_PAGES or not
- */
-#define _PAGE_F_SECOND 0x00008000 /* full page: hidx bits */
-#define _PAGE_F_GIX 0x00007000 /* full page: hidx bits */
+#define _PAGE_COMBO 0x00020000 /* this is a combo 4k page */
+#define _PAGE_4K_PFN 0x00040000 /* PFN is for a single 4k page */
/* PTE flags to conserve for HPTE identification */
#define _PAGE_HPTEFLAGS (_PAGE_BUSY | _PAGE_HASHPTE | _PAGE_COMBO)
diff --git a/arch/powerpc/include/asm/book3s/64/hash.h b/arch/powerpc/include/asm/book3s/64/hash.h
index 67146f108b7e..13da60dd0a17 100644
--- a/arch/powerpc/include/asm/book3s/64/hash.h
+++ b/arch/powerpc/include/asm/book3s/64/hash.h
@@ -83,7 +83,11 @@
#define _PAGE_DIRTY 0x0080 /* C: page changed */
#define _PAGE_ACCESSED 0x0100 /* R: page referenced */
#define _PAGE_RW 0x0200 /* software: user write access allowed */
+#define _PAGE_HASHPTE 0x0400 /* software: pte has an associated HPTE */
#define _PAGE_BUSY 0x0800 /* software: PTE & hash are busy */
+#define _PAGE_F_GIX 0x7000 /* full page: hidx bits */
+#define _PAGE_F_SECOND 0x8000 /* Whether to use secondary hash or not */
+#define _PAGE_SPECIAL 0x10000 /* software: special page */
/* No separate kernel read-only */
#define _PAGE_KERNEL_RW (_PAGE_RW | _PAGE_DIRTY) /* user access blocked by key */
diff --git a/arch/powerpc/mm/hash64_64k.c b/arch/powerpc/mm/hash64_64k.c
index c40ee12cc922..1fabf7c9ecf2 100644
--- a/arch/powerpc/mm/hash64_64k.c
+++ b/arch/powerpc/mm/hash64_64k.c
@@ -125,7 +125,7 @@ int __hash_page_4K(unsigned long ea, unsigned long access, unsigned long vsid,
*/
if (!(old_pte & _PAGE_COMBO)) {
flush_hash_page(vpn, rpte, MMU_PAGE_64K, ssize, flags);
- old_pte &= ~_PAGE_HPTE_SUB;
+ old_pte &= ~_PAGE_HASHPTE | _PAGE_F_GIX | _PAGE_F_SECOND;
goto htab_insert_hpte;
}
/*
@@ -212,7 +212,7 @@ repeat:
* nobody is undating hidx.
*/
rpte.hidx[subpg_index] = (unsigned char)(slot << 4 | 0x1 << 3);
- new_pte |= _PAGE_HPTE_SUB0;
+ new_pte |= _PAGE_HASHPTE;
/*
* check __real_pte for details on matching smp_rmb()
*/
diff --git a/arch/powerpc/mm/hash_low_64.S b/arch/powerpc/mm/hash_low_64.S
index 6b4d4c1d0628..359839a57f26 100644
--- a/arch/powerpc/mm/hash_low_64.S
+++ b/arch/powerpc/mm/hash_low_64.S
@@ -285,7 +285,7 @@ htab_modify_pte:
/* Secondary group ? if yes, get a inverted hash value */
mr r5,r28
- andi. r0,r31,_PAGE_SECONDARY
+ andi. r0,r31,_PAGE_F_SECOND
beq 1f
not r5,r5
1:
@@ -473,11 +473,7 @@ ht64_insert_pte:
lis r0,_PAGE_HPTEFLAGS at h
ori r0,r0,_PAGE_HPTEFLAGS at l
andc r30,r30,r0
-#ifdef CONFIG_PPC_64K_PAGES
- oris r30,r30,_PAGE_HPTE_SUB0 at h
-#else
ori r30,r30,_PAGE_HASHPTE
-#endif
/* Phyical address in r5 */
rldicl r5,r31,64-PTE_RPN_SHIFT,PTE_RPN_SHIFT
sldi r5,r5,PAGE_SHIFT
diff --git a/arch/powerpc/mm/hugetlbpage-hash64.c b/arch/powerpc/mm/hugetlbpage-hash64.c
index d94b1af53a93..7584e8445512 100644
--- a/arch/powerpc/mm/hugetlbpage-hash64.c
+++ b/arch/powerpc/mm/hugetlbpage-hash64.c
@@ -91,11 +91,8 @@ int __hash_page_huge(unsigned long ea, unsigned long access, unsigned long vsid,
pa = pte_pfn(__pte(old_pte)) << PAGE_SHIFT;
/* clear HPTE slot informations in new PTE */
-#ifdef CONFIG_PPC_64K_PAGES
- new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | _PAGE_HPTE_SUB0;
-#else
new_pte = (new_pte & ~_PAGE_HPTEFLAGS) | _PAGE_HASHPTE;
-#endif
+
/* Add in WIMG bits */
rflags |= (new_pte & (_PAGE_WRITETHRU | _PAGE_NO_CACHE |
_PAGE_COHERENT | _PAGE_GUARDED));
diff --git a/arch/powerpc/mm/pgtable_64.c b/arch/powerpc/mm/pgtable_64.c
index d692ae31cfc7..3967e3cce03e 100644
--- a/arch/powerpc/mm/pgtable_64.c
+++ b/arch/powerpc/mm/pgtable_64.c
@@ -625,7 +625,7 @@ void pmdp_splitting_flush(struct vm_area_struct *vma,
"1: ldarx %0,0,%3\n\
andi. %1,%0,%6\n\
bne- 1b \n\
- ori %1,%0,%4 \n\
+ oris %1,%0,%4 at h \n\
stdcx. %1,0,%3 \n\
bne- 1b"
: "=&r" (old), "=&r" (tmp), "=m" (*pmdp)
--
2.5.0
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