Re: [PATCH V4 07/18] powerpc/mm: Update masked bits for linux page table
From: Paul Mackerras <hidden>
Date: 2016-02-25 04:53:09
On Tue, Feb 23, 2016 at 10:18:09AM +0530, Aneesh Kumar K.V wrote:
quoted hunk ↗ jump to hunk
We now use physical address in upper page table tree levels. Even though they are aligned to their size, for the masked bits we use the overloaded bit positions as per PowerISA 3.0. We keep the bad bits check as it is, and will use conditional there when adding radix. Bad bits check also check for reserved bits and we oveload some of the reserved fields of radix in hash config. Signed-off-by: Aneesh Kumar K.V <redacted> --- arch/powerpc/include/asm/book3s/64/hash-64k.h | 15 ++++++--------- 1 file changed, 6 insertions(+), 9 deletions(-)diff --git a/arch/powerpc/include/asm/book3s/64/hash-64k.h b/arch/powerpc/include/asm/book3s/64/hash-64k.h index f0f5f91d7909..60c2c912c3a7 100644 --- a/arch/powerpc/include/asm/book3s/64/hash-64k.h +++ b/arch/powerpc/include/asm/book3s/64/hash-64k.h@@ -60,15 +60,12 @@ #define PTE_FRAG_SIZE_SHIFT 12 #define PTE_FRAG_SIZE (1UL << PTE_FRAG_SIZE_SHIFT) -/* - * Bits to mask out from a PMD to get to the PTE page - * PMDs point to PTE table fragments which are PTE_FRAG_SIZE aligned. - */ -#define PMD_MASKED_BITS (PTE_FRAG_SIZE - 1) -/* Bits to mask out from a PGD/PUD to get to the PMD page */ -#define PUD_MASKED_BITS 0x1ff -/* FIXME!! Will be fixed in next patch */ -#define PGD_MASKED_BITS 0 +/* Bits to mask out from a PMD to get to the PTE page */ +#define PMD_MASKED_BITS 0xc0000000000000ffUL +/* Bits to mask out from a PUD to get to the PMD page */ +#define PUD_MASKED_BITS 0xc0000000000000ffUL +/* Bits to mask out from a PGD to get to the PUD page */ +#define PGD_MASKED_BITS 0xc0000000000000ffUL
Why not fold this into the previous patch? (and include this patch's commentary in the previous patch's commentary, of course) Paul.